xref: /netbsd-src/external/gpl3/binutils/dist/bfd/elflink.c (revision dd7241df2fae9da4ea2bd20a68f001fa86ecf909)
1 /* ELF linking support for BFD.
2    Copyright (C) 1995-2024 Free Software Foundation, Inc.
3 
4    This file is part of BFD, the Binary File Descriptor library.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19    MA 02110-1301, USA.  */
20 
21 #include "sysdep.h"
22 #include "bfd.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
29 #include "objalloc.h"
30 #if BFD_SUPPORTS_PLUGINS
31 #include "plugin-api.h"
32 #include "plugin.h"
33 #endif
34 
35 #include <limits.h>
36 #ifndef CHAR_BIT
37 #define CHAR_BIT 8
38 #endif
39 
40 /* This struct is used to pass information to routines called via
41    elf_link_hash_traverse which must return failure.  */
42 
43 struct elf_info_failed
44 {
45   struct bfd_link_info *info;
46   bool failed;
47 };
48 
49 static bool _bfd_elf_fix_symbol_flags
50   (struct elf_link_hash_entry *, struct elf_info_failed *);
51 
52 asection *
_bfd_elf_section_for_symbol(struct elf_reloc_cookie * cookie,unsigned long r_symndx,bool discard)53 _bfd_elf_section_for_symbol (struct elf_reloc_cookie *cookie,
54 			     unsigned long r_symndx,
55 			     bool discard)
56 {
57   if (r_symndx >= cookie->locsymcount
58       || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
59     {
60       struct elf_link_hash_entry *h;
61 
62       h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
63 
64       while (h->root.type == bfd_link_hash_indirect
65 	     || h->root.type == bfd_link_hash_warning)
66 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
67 
68       if ((h->root.type == bfd_link_hash_defined
69 	   || h->root.type == bfd_link_hash_defweak)
70 	   && discarded_section (h->root.u.def.section))
71 	return h->root.u.def.section;
72       else
73 	return NULL;
74     }
75   else
76     {
77       /* It's not a relocation against a global symbol,
78 	 but it could be a relocation against a local
79 	 symbol for a discarded section.  */
80       asection *isec;
81       Elf_Internal_Sym *isym;
82 
83       /* Need to: get the symbol; get the section.  */
84       isym = &cookie->locsyms[r_symndx];
85       isec = bfd_section_from_elf_index (cookie->abfd, isym->st_shndx);
86       if (isec != NULL
87 	  && discard ? discarded_section (isec) : 1)
88 	return isec;
89      }
90   return NULL;
91 }
92 
93 /* Define a symbol in a dynamic linkage section.  */
94 
95 struct elf_link_hash_entry *
_bfd_elf_define_linkage_sym(bfd * abfd,struct bfd_link_info * info,asection * sec,const char * name)96 _bfd_elf_define_linkage_sym (bfd *abfd,
97 			     struct bfd_link_info *info,
98 			     asection *sec,
99 			     const char *name)
100 {
101   struct elf_link_hash_entry *h;
102   struct bfd_link_hash_entry *bh;
103   const struct elf_backend_data *bed;
104 
105   h = elf_link_hash_lookup (elf_hash_table (info), name, false, false, false);
106   if (h != NULL)
107     {
108       /* Zap symbol defined in an as-needed lib that wasn't linked.
109 	 This is a symptom of a larger problem:  Absolute symbols
110 	 defined in shared libraries can't be overridden, because we
111 	 lose the link to the bfd which is via the symbol section.  */
112       h->root.type = bfd_link_hash_new;
113       bh = &h->root;
114     }
115   else
116     bh = NULL;
117 
118   bed = get_elf_backend_data (abfd);
119   if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
120 					 sec, 0, NULL, false, bed->collect,
121 					 &bh))
122     return NULL;
123   h = (struct elf_link_hash_entry *) bh;
124   BFD_ASSERT (h != NULL);
125   h->def_regular = 1;
126   h->non_elf = 0;
127   h->root.linker_def = 1;
128   h->type = STT_OBJECT;
129   if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
130     h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
131 
132   (*bed->elf_backend_hide_symbol) (info, h, true);
133   return h;
134 }
135 
136 bool
_bfd_elf_create_got_section(bfd * abfd,struct bfd_link_info * info)137 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
138 {
139   flagword flags;
140   asection *s;
141   struct elf_link_hash_entry *h;
142   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
143   struct elf_link_hash_table *htab = elf_hash_table (info);
144 
145   /* This function may be called more than once.  */
146   if (htab->sgot != NULL)
147     return true;
148 
149   flags = bed->dynamic_sec_flags;
150 
151   s = bfd_make_section_anyway_with_flags (abfd,
152 					  (bed->rela_plts_and_copies_p
153 					   ? ".rela.got" : ".rel.got"),
154 					  (bed->dynamic_sec_flags
155 					   | SEC_READONLY));
156   if (s == NULL
157       || !bfd_set_section_alignment (s, bed->s->log_file_align))
158     return false;
159   htab->srelgot = s;
160 
161   s = bfd_make_section_anyway_with_flags (abfd, ".got", flags);
162   if (s == NULL
163       || !bfd_set_section_alignment (s, bed->s->log_file_align))
164     return false;
165   htab->sgot = s;
166 
167   if (bed->want_got_plt)
168     {
169       s = bfd_make_section_anyway_with_flags (abfd, ".got.plt", flags);
170       if (s == NULL
171 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
172 	return false;
173       htab->sgotplt = s;
174     }
175 
176   /* The first bit of the global offset table is the header.  */
177   s->size += bed->got_header_size;
178 
179   if (bed->want_got_sym)
180     {
181       /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
182 	 (or .got.plt) section.  We don't do this in the linker script
183 	 because we don't want to define the symbol if we are not creating
184 	 a global offset table.  */
185       h = _bfd_elf_define_linkage_sym (abfd, info, s,
186 				       "_GLOBAL_OFFSET_TABLE_");
187       elf_hash_table (info)->hgot = h;
188       if (h == NULL)
189 	return false;
190     }
191 
192   return true;
193 }
194 
195 /* Create a strtab to hold the dynamic symbol names.  */
196 static bool
_bfd_elf_link_create_dynstrtab(bfd * abfd,struct bfd_link_info * info)197 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
198 {
199   struct elf_link_hash_table *hash_table;
200 
201   hash_table = elf_hash_table (info);
202   if (hash_table->dynobj == NULL)
203     {
204       /* We may not set dynobj, an input file holding linker created
205 	 dynamic sections to abfd, which may be a dynamic object with
206 	 its own dynamic sections.  We need to find a normal input file
207 	 to hold linker created sections if possible.  */
208       if ((abfd->flags & (DYNAMIC | BFD_PLUGIN)) != 0)
209 	{
210 	  bfd *ibfd;
211 	  asection *s;
212 	  for (ibfd = info->input_bfds; ibfd; ibfd = ibfd->link.next)
213 	    if ((ibfd->flags
214 		 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0
215 		&& bfd_get_flavour (ibfd) == bfd_target_elf_flavour
216 		&& elf_object_id (ibfd) == elf_hash_table_id (hash_table)
217 		&& !((s = ibfd->sections) != NULL
218 		     && s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS))
219 	      {
220 		abfd = ibfd;
221 		break;
222 	      }
223 	}
224       hash_table->dynobj = abfd;
225     }
226 
227   if (hash_table->dynstr == NULL)
228     {
229       hash_table->dynstr = _bfd_elf_strtab_init ();
230       if (hash_table->dynstr == NULL)
231 	return false;
232     }
233   return true;
234 }
235 
236 /* Create some sections which will be filled in with dynamic linking
237    information.  ABFD is an input file which requires dynamic sections
238    to be created.  The dynamic sections take up virtual memory space
239    when the final executable is run, so we need to create them before
240    addresses are assigned to the output sections.  We work out the
241    actual contents and size of these sections later.  */
242 
243 bool
_bfd_elf_link_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)244 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
245 {
246   flagword flags;
247   asection *s;
248   const struct elf_backend_data *bed;
249   struct elf_link_hash_entry *h;
250 
251   if (! is_elf_hash_table (info->hash))
252     return false;
253 
254   if (elf_hash_table (info)->dynamic_sections_created)
255     return true;
256 
257   if (!_bfd_elf_link_create_dynstrtab (abfd, info))
258     return false;
259 
260   abfd = elf_hash_table (info)->dynobj;
261   bed = get_elf_backend_data (abfd);
262 
263   flags = bed->dynamic_sec_flags;
264 
265   /* A dynamically linked executable has a .interp section, but a
266      shared library does not.  */
267   if (bfd_link_executable (info) && !info->nointerp)
268     {
269       s = bfd_make_section_anyway_with_flags (abfd, ".interp",
270 					      flags | SEC_READONLY);
271       if (s == NULL)
272 	return false;
273     }
274 
275   /* Create sections to hold version informations.  These are removed
276      if they are not needed.  */
277   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version_d",
278 					  flags | SEC_READONLY);
279   if (s == NULL
280       || !bfd_set_section_alignment (s, bed->s->log_file_align))
281     return false;
282 
283   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version",
284 					  flags | SEC_READONLY);
285   if (s == NULL
286       || !bfd_set_section_alignment (s, 1))
287     return false;
288 
289   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version_r",
290 					  flags | SEC_READONLY);
291   if (s == NULL
292       || !bfd_set_section_alignment (s, bed->s->log_file_align))
293     return false;
294 
295   s = bfd_make_section_anyway_with_flags (abfd, ".dynsym",
296 					  flags | SEC_READONLY);
297   if (s == NULL
298       || !bfd_set_section_alignment (s, bed->s->log_file_align))
299     return false;
300   elf_hash_table (info)->dynsym = s;
301 
302   s = bfd_make_section_anyway_with_flags (abfd, ".dynstr",
303 					  flags | SEC_READONLY);
304   if (s == NULL)
305     return false;
306 
307   s = bfd_make_section_anyway_with_flags (abfd, ".dynamic", flags);
308   if (s == NULL
309       || !bfd_set_section_alignment (s, bed->s->log_file_align))
310     return false;
311 
312   /* The special symbol _DYNAMIC is always set to the start of the
313      .dynamic section.  We could set _DYNAMIC in a linker script, but we
314      only want to define it if we are, in fact, creating a .dynamic
315      section.  We don't want to define it if there is no .dynamic
316      section, since on some ELF platforms the start up code examines it
317      to decide how to initialize the process.  */
318   h = _bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC");
319   elf_hash_table (info)->hdynamic = h;
320   if (h == NULL)
321     return false;
322 
323   if (info->emit_hash)
324     {
325       s = bfd_make_section_anyway_with_flags (abfd, ".hash",
326 					      flags | SEC_READONLY);
327       if (s == NULL
328 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
329 	return false;
330       elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
331     }
332 
333   if (info->emit_gnu_hash && bed->record_xhash_symbol == NULL)
334     {
335       s = bfd_make_section_anyway_with_flags (abfd, ".gnu.hash",
336 					      flags | SEC_READONLY);
337       if (s == NULL
338 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
339 	return false;
340       /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
341 	 4 32-bit words followed by variable count of 64-bit words, then
342 	 variable count of 32-bit words.  */
343       if (bed->s->arch_size == 64)
344 	elf_section_data (s)->this_hdr.sh_entsize = 0;
345       else
346 	elf_section_data (s)->this_hdr.sh_entsize = 4;
347     }
348 
349   if (info->enable_dt_relr)
350     {
351       s = bfd_make_section_anyway_with_flags (abfd, ".relr.dyn",
352 					      (bed->dynamic_sec_flags
353 					       | SEC_READONLY));
354       if (s == NULL
355 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
356 	return false;
357       elf_hash_table (info)->srelrdyn = s;
358     }
359 
360   /* Let the backend create the rest of the sections.  This lets the
361      backend set the right flags.  The backend will normally create
362      the .got and .plt sections.  */
363   if (bed->elf_backend_create_dynamic_sections == NULL
364       || ! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
365     return false;
366 
367   elf_hash_table (info)->dynamic_sections_created = true;
368 
369   return true;
370 }
371 
372 /* Create dynamic sections when linking against a dynamic object.  */
373 
374 bool
_bfd_elf_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)375 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
376 {
377   flagword flags, pltflags;
378   struct elf_link_hash_entry *h;
379   asection *s;
380   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
381   struct elf_link_hash_table *htab = elf_hash_table (info);
382 
383   /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
384      .rel[a].bss sections.  */
385   flags = bed->dynamic_sec_flags;
386 
387   pltflags = flags;
388   if (bed->plt_not_loaded)
389     /* We do not clear SEC_ALLOC here because we still want the OS to
390        allocate space for the section; it's just that there's nothing
391        to read in from the object file.  */
392     pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
393   else
394     pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
395   if (bed->plt_readonly)
396     pltflags |= SEC_READONLY;
397 
398   s = bfd_make_section_anyway_with_flags (abfd, ".plt", pltflags);
399   if (s == NULL
400       || !bfd_set_section_alignment (s, bed->plt_alignment))
401     return false;
402   htab->splt = s;
403 
404   /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
405      .plt section.  */
406   if (bed->want_plt_sym)
407     {
408       h = _bfd_elf_define_linkage_sym (abfd, info, s,
409 				       "_PROCEDURE_LINKAGE_TABLE_");
410       elf_hash_table (info)->hplt = h;
411       if (h == NULL)
412 	return false;
413     }
414 
415   s = bfd_make_section_anyway_with_flags (abfd,
416 					  (bed->rela_plts_and_copies_p
417 					   ? ".rela.plt" : ".rel.plt"),
418 					  flags | SEC_READONLY);
419   if (s == NULL
420       || !bfd_set_section_alignment (s, bed->s->log_file_align))
421     return false;
422   htab->srelplt = s;
423 
424   if (! _bfd_elf_create_got_section (abfd, info))
425     return false;
426 
427   if (bed->want_dynbss)
428     {
429       /* The .dynbss section is a place to put symbols which are defined
430 	 by dynamic objects, are referenced by regular objects, and are
431 	 not functions.  We must allocate space for them in the process
432 	 image and use a R_*_COPY reloc to tell the dynamic linker to
433 	 initialize them at run time.  The linker script puts the .dynbss
434 	 section into the .bss section of the final image.  */
435       s = bfd_make_section_anyway_with_flags (abfd, ".dynbss",
436 					      SEC_ALLOC | SEC_LINKER_CREATED);
437       if (s == NULL)
438 	return false;
439       htab->sdynbss = s;
440 
441       if (bed->want_dynrelro)
442 	{
443 	  /* Similarly, but for symbols that were originally in read-only
444 	     sections.  This section doesn't really need to have contents,
445 	     but make it like other .data.rel.ro sections.  */
446 	  s = bfd_make_section_anyway_with_flags (abfd, ".data.rel.ro",
447 						  flags);
448 	  if (s == NULL)
449 	    return false;
450 	  htab->sdynrelro = s;
451 	}
452 
453       /* The .rel[a].bss section holds copy relocs.  This section is not
454 	 normally needed.  We need to create it here, though, so that the
455 	 linker will map it to an output section.  We can't just create it
456 	 only if we need it, because we will not know whether we need it
457 	 until we have seen all the input files, and the first time the
458 	 main linker code calls BFD after examining all the input files
459 	 (size_dynamic_sections) the input sections have already been
460 	 mapped to the output sections.  If the section turns out not to
461 	 be needed, we can discard it later.  We will never need this
462 	 section when generating a shared object, since they do not use
463 	 copy relocs.  */
464       if (bfd_link_executable (info))
465 	{
466 	  s = bfd_make_section_anyway_with_flags (abfd,
467 						  (bed->rela_plts_and_copies_p
468 						   ? ".rela.bss" : ".rel.bss"),
469 						  flags | SEC_READONLY);
470 	  if (s == NULL
471 	      || !bfd_set_section_alignment (s, bed->s->log_file_align))
472 	    return false;
473 	  htab->srelbss = s;
474 
475 	  if (bed->want_dynrelro)
476 	    {
477 	      s = (bfd_make_section_anyway_with_flags
478 		   (abfd, (bed->rela_plts_and_copies_p
479 			   ? ".rela.data.rel.ro" : ".rel.data.rel.ro"),
480 		    flags | SEC_READONLY));
481 	      if (s == NULL
482 		  || !bfd_set_section_alignment (s, bed->s->log_file_align))
483 		return false;
484 	      htab->sreldynrelro = s;
485 	    }
486 	}
487     }
488 
489   return true;
490 }
491 
492 /* Record a new dynamic symbol.  We record the dynamic symbols as we
493    read the input files, since we need to have a list of all of them
494    before we can determine the final sizes of the output sections.
495    Note that we may actually call this function even though we are not
496    going to output any dynamic symbols; in some cases we know that a
497    symbol should be in the dynamic symbol table, but only if there is
498    one.  */
499 
500 bool
bfd_elf_link_record_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)501 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
502 				    struct elf_link_hash_entry *h)
503 {
504   if (h->dynindx == -1)
505     {
506       struct elf_strtab_hash *dynstr;
507       char *p;
508       const char *name;
509       size_t indx;
510 
511       if (h->root.type == bfd_link_hash_defined
512 	  || h->root.type == bfd_link_hash_defweak)
513 	{
514 	  /* An IR symbol should not be made dynamic.  */
515 	  if (h->root.u.def.section != NULL
516 	      && h->root.u.def.section->owner != NULL
517 	      && (h->root.u.def.section->owner->flags & BFD_PLUGIN) != 0)
518 	    return true;
519 	}
520 
521       /* XXX: The ABI draft says the linker must turn hidden and
522 	 internal symbols into STB_LOCAL symbols when producing the
523 	 DSO. However, if ld.so honors st_other in the dynamic table,
524 	 this would not be necessary.  */
525       switch (ELF_ST_VISIBILITY (h->other))
526 	{
527 	case STV_INTERNAL:
528 	case STV_HIDDEN:
529 	  if (h->root.type != bfd_link_hash_undefined
530 	      && h->root.type != bfd_link_hash_undefweak)
531 	    {
532 	      h->forced_local = 1;
533 	      if (!elf_hash_table (info)->is_relocatable_executable
534 		  || ((h->root.type == bfd_link_hash_defined
535 		       || h->root.type == bfd_link_hash_defweak)
536 		      && h->root.u.def.section->owner != NULL
537 		      && h->root.u.def.section->owner->no_export)
538 		  || (h->root.type == bfd_link_hash_common
539 		      && h->root.u.c.p->section->owner != NULL
540 		      && h->root.u.c.p->section->owner->no_export))
541 		return true;
542 	    }
543 
544 	default:
545 	  break;
546 	}
547 
548       h->dynindx = elf_hash_table (info)->dynsymcount;
549       ++elf_hash_table (info)->dynsymcount;
550 
551       dynstr = elf_hash_table (info)->dynstr;
552       if (dynstr == NULL)
553 	{
554 	  /* Create a strtab to hold the dynamic symbol names.  */
555 	  elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
556 	  if (dynstr == NULL)
557 	    return false;
558 	}
559 
560       /* We don't put any version information in the dynamic string
561 	 table.  */
562       name = h->root.root.string;
563       p = strchr (name, ELF_VER_CHR);
564       if (p != NULL)
565 	/* We know that the p points into writable memory.  In fact,
566 	   there are only a few symbols that have read-only names, being
567 	   those like _GLOBAL_OFFSET_TABLE_ that are created specially
568 	   by the backends.  Most symbols will have names pointing into
569 	   an ELF string table read from a file, or to objalloc memory.  */
570 	*p = 0;
571 
572       indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
573 
574       if (p != NULL)
575 	*p = ELF_VER_CHR;
576 
577       if (indx == (size_t) -1)
578 	return false;
579       h->dynstr_index = indx;
580     }
581 
582   return true;
583 }
584 
585 /* Mark a symbol dynamic.  */
586 
587 static void
bfd_elf_link_mark_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)588 bfd_elf_link_mark_dynamic_symbol (struct bfd_link_info *info,
589 				  struct elf_link_hash_entry *h,
590 				  Elf_Internal_Sym *sym)
591 {
592   struct bfd_elf_dynamic_list *d = info->dynamic_list;
593 
594   /* It may be called more than once on the same H.  */
595   if(h->dynamic || bfd_link_relocatable (info))
596     return;
597 
598   if ((info->dynamic_data
599        && (h->type == STT_OBJECT
600 	   || h->type == STT_COMMON
601 	   || (sym != NULL
602 	       && (ELF_ST_TYPE (sym->st_info) == STT_OBJECT
603 		   || ELF_ST_TYPE (sym->st_info) == STT_COMMON))))
604       || (d != NULL
605 	  && h->non_elf
606 	  && (*d->match) (&d->head, NULL, h->root.root.string)))
607     {
608       h->dynamic = 1;
609       /* NB: If a symbol is made dynamic by --dynamic-list, it has
610 	 non-IR reference.  */
611       h->root.non_ir_ref_dynamic = 1;
612     }
613 }
614 
615 /* Record an assignment to a symbol made by a linker script.  We need
616    this in case some dynamic object refers to this symbol.  */
617 
618 bool
bfd_elf_record_link_assignment(bfd * output_bfd,struct bfd_link_info * info,const char * name,bool provide,bool hidden)619 bfd_elf_record_link_assignment (bfd *output_bfd,
620 				struct bfd_link_info *info,
621 				const char *name,
622 				bool provide,
623 				bool hidden)
624 {
625   struct elf_link_hash_entry *h, *hv;
626   struct elf_link_hash_table *htab;
627   const struct elf_backend_data *bed;
628 
629   if (!is_elf_hash_table (info->hash))
630     return true;
631 
632   htab = elf_hash_table (info);
633   h = elf_link_hash_lookup (htab, name, !provide, true, false);
634   if (h == NULL)
635     return provide;
636 
637   if (h->root.type == bfd_link_hash_warning)
638     h = (struct elf_link_hash_entry *) h->root.u.i.link;
639 
640   if (h->versioned == unknown)
641     {
642       /* Set versioned if symbol version is unknown.  */
643       char *version = strrchr (name, ELF_VER_CHR);
644       if (version)
645 	{
646 	  if (version > name && version[-1] != ELF_VER_CHR)
647 	    h->versioned = versioned_hidden;
648 	  else
649 	    h->versioned = versioned;
650 	}
651     }
652 
653   /* Symbols defined in a linker script but not referenced anywhere
654      else will have non_elf set.  */
655   if (h->non_elf)
656     {
657       bfd_elf_link_mark_dynamic_symbol (info, h, NULL);
658       h->non_elf = 0;
659     }
660 
661   switch (h->root.type)
662     {
663     case bfd_link_hash_defined:
664     case bfd_link_hash_defweak:
665     case bfd_link_hash_common:
666       break;
667     case bfd_link_hash_undefweak:
668     case bfd_link_hash_undefined:
669       /* Since we're defining the symbol, don't let it seem to have not
670 	 been defined.  record_dynamic_symbol and size_dynamic_sections
671 	 may depend on this.  */
672       h->root.type = bfd_link_hash_new;
673       if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
674 	bfd_link_repair_undef_list (&htab->root);
675       break;
676     case bfd_link_hash_new:
677       break;
678     case bfd_link_hash_indirect:
679       /* We had a versioned symbol in a dynamic library.  We make the
680 	 the versioned symbol point to this one.  */
681       bed = get_elf_backend_data (output_bfd);
682       hv = h;
683       while (hv->root.type == bfd_link_hash_indirect
684 	     || hv->root.type == bfd_link_hash_warning)
685 	hv = (struct elf_link_hash_entry *) hv->root.u.i.link;
686       /* We don't need to update h->root.u since linker will set them
687 	 later.  */
688       h->root.type = bfd_link_hash_undefined;
689       hv->root.type = bfd_link_hash_indirect;
690       hv->root.u.i.link = (struct bfd_link_hash_entry *) h;
691       (*bed->elf_backend_copy_indirect_symbol) (info, h, hv);
692       break;
693     default:
694       BFD_FAIL ();
695       return false;
696     }
697 
698   /* If this symbol is being provided by the linker script, and it is
699      currently defined by a dynamic object, but not by a regular
700      object, then mark it as undefined so that the generic linker will
701      force the correct value.  */
702   if (provide
703       && h->def_dynamic
704       && !h->def_regular)
705     h->root.type = bfd_link_hash_undefined;
706 
707   /* If this symbol is currently defined by a dynamic object, but not
708      by a regular object, then clear out any version information because
709      the symbol will not be associated with the dynamic object any
710      more.  */
711   if (h->def_dynamic && !h->def_regular)
712     h->verinfo.verdef = NULL;
713 
714   /* Make sure this symbol is not garbage collected.  */
715   h->mark = 1;
716 
717   h->def_regular = 1;
718 
719   if (hidden)
720     {
721       bed = get_elf_backend_data (output_bfd);
722       if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
723 	h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
724       (*bed->elf_backend_hide_symbol) (info, h, true);
725     }
726 
727   /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
728      and executables.  */
729   if (!bfd_link_relocatable (info)
730       && h->dynindx != -1
731       && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
732 	  || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
733     h->forced_local = 1;
734 
735   if ((h->def_dynamic
736        || h->ref_dynamic
737        || bfd_link_dll (info)
738        || elf_hash_table (info)->is_relocatable_executable)
739       && !h->forced_local
740       && h->dynindx == -1)
741     {
742       if (! bfd_elf_link_record_dynamic_symbol (info, h))
743 	return false;
744 
745       /* If this is a weak defined symbol, and we know a corresponding
746 	 real symbol from the same dynamic object, make sure the real
747 	 symbol is also made into a dynamic symbol.  */
748       if (h->is_weakalias)
749 	{
750 	  struct elf_link_hash_entry *def = weakdef (h);
751 
752 	  if (def->dynindx == -1
753 	      && !bfd_elf_link_record_dynamic_symbol (info, def))
754 	    return false;
755 	}
756     }
757 
758   return true;
759 }
760 
761 /* Record a new local dynamic symbol.  Returns 0 on failure, 1 on
762    success, and 2 on a failure caused by attempting to record a symbol
763    in a discarded section, eg. a discarded link-once section symbol.  */
764 
765 int
bfd_elf_link_record_local_dynamic_symbol(struct bfd_link_info * info,bfd * input_bfd,long input_indx)766 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
767 					  bfd *input_bfd,
768 					  long input_indx)
769 {
770   size_t amt;
771   struct elf_link_local_dynamic_entry *entry;
772   struct elf_link_hash_table *eht;
773   struct elf_strtab_hash *dynstr;
774   size_t dynstr_index;
775   char *name;
776   Elf_External_Sym_Shndx eshndx;
777   char esym[sizeof (Elf64_External_Sym)];
778 
779   if (! is_elf_hash_table (info->hash))
780     return 0;
781 
782   /* See if the entry exists already.  */
783   for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
784     if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
785       return 1;
786 
787   amt = sizeof (*entry);
788   entry = (struct elf_link_local_dynamic_entry *) bfd_alloc (input_bfd, amt);
789   if (entry == NULL)
790     return 0;
791 
792   /* Go find the symbol, so that we can find it's name.  */
793   if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
794 			     1, input_indx, &entry->isym, esym, &eshndx))
795     {
796       bfd_release (input_bfd, entry);
797       return 0;
798     }
799 
800   if (entry->isym.st_shndx != SHN_UNDEF
801       && entry->isym.st_shndx < SHN_LORESERVE)
802     {
803       asection *s;
804 
805       s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
806       if (s == NULL || bfd_is_abs_section (s->output_section))
807 	{
808 	  /* We can still bfd_release here as nothing has done another
809 	     bfd_alloc.  We can't do this later in this function.  */
810 	  bfd_release (input_bfd, entry);
811 	  return 2;
812 	}
813     }
814 
815   name = (bfd_elf_string_from_elf_section
816 	  (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
817 	   entry->isym.st_name));
818 
819   dynstr = elf_hash_table (info)->dynstr;
820   if (dynstr == NULL)
821     {
822       /* Create a strtab to hold the dynamic symbol names.  */
823       elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
824       if (dynstr == NULL)
825 	return 0;
826     }
827 
828   dynstr_index = _bfd_elf_strtab_add (dynstr, name, false);
829   if (dynstr_index == (size_t) -1)
830     return 0;
831   entry->isym.st_name = dynstr_index;
832 
833   eht = elf_hash_table (info);
834 
835   entry->next = eht->dynlocal;
836   eht->dynlocal = entry;
837   entry->input_bfd = input_bfd;
838   entry->input_indx = input_indx;
839   eht->dynsymcount++;
840 
841   /* Whatever binding the symbol had before, it's now local.  */
842   entry->isym.st_info
843     = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
844 
845   /* The dynindx will be set at the end of size_dynamic_sections.  */
846 
847   return 1;
848 }
849 
850 /* Return the dynindex of a local dynamic symbol.  */
851 
852 long
_bfd_elf_link_lookup_local_dynindx(struct bfd_link_info * info,bfd * input_bfd,long input_indx)853 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
854 				    bfd *input_bfd,
855 				    long input_indx)
856 {
857   struct elf_link_local_dynamic_entry *e;
858 
859   for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
860     if (e->input_bfd == input_bfd && e->input_indx == input_indx)
861       return e->dynindx;
862   return -1;
863 }
864 
865 /* This function is used to renumber the dynamic symbols, if some of
866    them are removed because they are marked as local.  This is called
867    via elf_link_hash_traverse.  */
868 
869 static bool
elf_link_renumber_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)870 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
871 				      void *data)
872 {
873   size_t *count = (size_t *) data;
874 
875   if (h->forced_local)
876     return true;
877 
878   if (h->dynindx != -1)
879     h->dynindx = ++(*count);
880 
881   return true;
882 }
883 
884 
885 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
886    STB_LOCAL binding.  */
887 
888 static bool
elf_link_renumber_local_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)889 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
890 					    void *data)
891 {
892   size_t *count = (size_t *) data;
893 
894   if (!h->forced_local)
895     return true;
896 
897   if (h->dynindx != -1)
898     h->dynindx = ++(*count);
899 
900   return true;
901 }
902 
903 /* Return true if the dynamic symbol for a given section should be
904    omitted when creating a shared library.  */
905 bool
_bfd_elf_omit_section_dynsym_default(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,asection * p)906 _bfd_elf_omit_section_dynsym_default (bfd *output_bfd ATTRIBUTE_UNUSED,
907 				      struct bfd_link_info *info,
908 				      asection *p)
909 {
910   struct elf_link_hash_table *htab;
911   asection *ip;
912 
913   switch (elf_section_data (p)->this_hdr.sh_type)
914     {
915     case SHT_PROGBITS:
916     case SHT_NOBITS:
917       /* If sh_type is yet undecided, assume it could be
918 	 SHT_PROGBITS/SHT_NOBITS.  */
919     case SHT_NULL:
920       htab = elf_hash_table (info);
921       if (htab->text_index_section != NULL)
922 	return p != htab->text_index_section && p != htab->data_index_section;
923 
924       return (htab->dynobj != NULL
925 	      && (ip = bfd_get_linker_section (htab->dynobj, p->name)) != NULL
926 	      && ip->output_section == p);
927 
928       /* There shouldn't be section relative relocations
929 	 against any other section.  */
930     default:
931       return true;
932     }
933 }
934 
935 bool
_bfd_elf_omit_section_dynsym_all(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,asection * p ATTRIBUTE_UNUSED)936 _bfd_elf_omit_section_dynsym_all
937     (bfd *output_bfd ATTRIBUTE_UNUSED,
938      struct bfd_link_info *info ATTRIBUTE_UNUSED,
939      asection *p ATTRIBUTE_UNUSED)
940 {
941   return true;
942 }
943 
944 /* Assign dynsym indices.  In a shared library we generate a section
945    symbol for each output section, which come first.  Next come symbols
946    which have been forced to local binding.  Then all of the back-end
947    allocated local dynamic syms, followed by the rest of the global
948    symbols.  If SECTION_SYM_COUNT is NULL, section dynindx is not set.
949    (This prevents the early call before elf_backend_init_index_section
950    and strip_excluded_output_sections setting dynindx for sections
951    that are stripped.)  */
952 
953 static unsigned long
_bfd_elf_link_renumber_dynsyms(bfd * output_bfd,struct bfd_link_info * info,unsigned long * section_sym_count)954 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
955 				struct bfd_link_info *info,
956 				unsigned long *section_sym_count)
957 {
958   unsigned long dynsymcount = 0;
959   bool do_sec = section_sym_count != NULL;
960 
961   if (bfd_link_pic (info)
962       || elf_hash_table (info)->is_relocatable_executable)
963     {
964       const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
965       asection *p;
966       for (p = output_bfd->sections; p ; p = p->next)
967 	if ((p->flags & SEC_EXCLUDE) == 0
968 	    && (p->flags & SEC_ALLOC) != 0
969 	    && elf_hash_table (info)->dynamic_relocs
970 	    && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
971 	  {
972 	    ++dynsymcount;
973 	    if (do_sec)
974 	      elf_section_data (p)->dynindx = dynsymcount;
975 	  }
976 	else if (do_sec)
977 	  elf_section_data (p)->dynindx = 0;
978     }
979   if (do_sec)
980     *section_sym_count = dynsymcount;
981 
982   elf_link_hash_traverse (elf_hash_table (info),
983 			  elf_link_renumber_local_hash_table_dynsyms,
984 			  &dynsymcount);
985 
986   if (elf_hash_table (info)->dynlocal)
987     {
988       struct elf_link_local_dynamic_entry *p;
989       for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
990 	p->dynindx = ++dynsymcount;
991     }
992   elf_hash_table (info)->local_dynsymcount = dynsymcount;
993 
994   elf_link_hash_traverse (elf_hash_table (info),
995 			  elf_link_renumber_hash_table_dynsyms,
996 			  &dynsymcount);
997 
998   /* There is an unused NULL entry at the head of the table which we
999      must account for in our count even if the table is empty since it
1000      is intended for the mandatory DT_SYMTAB tag (.dynsym section) in
1001      .dynamic section.  */
1002   dynsymcount++;
1003 
1004   elf_hash_table (info)->dynsymcount = dynsymcount;
1005   return dynsymcount;
1006 }
1007 
1008 /* Merge st_other field.  */
1009 
1010 static void
elf_merge_st_other(bfd * abfd,struct elf_link_hash_entry * h,unsigned int st_other,asection * sec,bool definition,bool dynamic)1011 elf_merge_st_other (bfd *abfd, struct elf_link_hash_entry *h,
1012 		    unsigned int st_other, asection *sec,
1013 		    bool definition, bool dynamic)
1014 {
1015   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1016 
1017   /* If st_other has a processor-specific meaning, specific
1018      code might be needed here.  */
1019   if (bed->elf_backend_merge_symbol_attribute)
1020     (*bed->elf_backend_merge_symbol_attribute) (h, st_other, definition,
1021 						dynamic);
1022 
1023   if (!dynamic)
1024     {
1025       unsigned symvis = ELF_ST_VISIBILITY (st_other);
1026       unsigned hvis = ELF_ST_VISIBILITY (h->other);
1027 
1028       /* Keep the most constraining visibility.  Leave the remainder
1029 	 of the st_other field to elf_backend_merge_symbol_attribute.  */
1030       if (symvis - 1 < hvis - 1)
1031 	h->other = symvis | (h->other & ~ELF_ST_VISIBILITY (-1));
1032     }
1033   else if (definition
1034 	   && ELF_ST_VISIBILITY (st_other) != STV_DEFAULT
1035 	   && (sec->flags & SEC_READONLY) == 0)
1036     h->protected_def = 1;
1037 }
1038 
1039 /* This function is called when we want to merge a new symbol with an
1040    existing symbol.  It handles the various cases which arise when we
1041    find a definition in a dynamic object, or when there is already a
1042    definition in a dynamic object.  The new symbol is described by
1043    NAME, SYM, PSEC, and PVALUE.  We set SYM_HASH to the hash table
1044    entry.  We set POLDBFD to the old symbol's BFD.  We set POLD_WEAK
1045    if the old symbol was weak.  We set POLD_ALIGNMENT to the alignment
1046    of an old common symbol.  We set OVERRIDE if the old symbol is
1047    overriding a new definition.  We set TYPE_CHANGE_OK if it is OK for
1048    the type to change.  We set SIZE_CHANGE_OK if it is OK for the size
1049    to change.  By OK to change, we mean that we shouldn't warn if the
1050    type or size does change.  */
1051 
1052 static bool
_bfd_elf_merge_symbol(bfd * abfd,struct bfd_link_info * info,const char * name,Elf_Internal_Sym * sym,asection ** psec,bfd_vma * pvalue,struct elf_link_hash_entry ** sym_hash,bfd ** poldbfd,bool * pold_weak,unsigned int * pold_alignment,bool * skip,bfd ** override,bool * type_change_ok,bool * size_change_ok,bool * matched)1053 _bfd_elf_merge_symbol (bfd *abfd,
1054 		       struct bfd_link_info *info,
1055 		       const char *name,
1056 		       Elf_Internal_Sym *sym,
1057 		       asection **psec,
1058 		       bfd_vma *pvalue,
1059 		       struct elf_link_hash_entry **sym_hash,
1060 		       bfd **poldbfd,
1061 		       bool *pold_weak,
1062 		       unsigned int *pold_alignment,
1063 		       bool *skip,
1064 		       bfd **override,
1065 		       bool *type_change_ok,
1066 		       bool *size_change_ok,
1067 		       bool *matched)
1068 {
1069   asection *sec, *oldsec;
1070   struct elf_link_hash_entry *h;
1071   struct elf_link_hash_entry *hi;
1072   struct elf_link_hash_entry *flip;
1073   int bind;
1074   bfd *oldbfd;
1075   bool newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
1076   bool newweak, oldweak, newfunc, oldfunc;
1077   const struct elf_backend_data *bed;
1078   char *new_version;
1079   bool default_sym = *matched;
1080   struct elf_link_hash_table *htab;
1081 
1082   *skip = false;
1083   *override = NULL;
1084 
1085   sec = *psec;
1086   bind = ELF_ST_BIND (sym->st_info);
1087 
1088   if (! bfd_is_und_section (sec))
1089     h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
1090   else
1091     h = ((struct elf_link_hash_entry *)
1092 	 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
1093   if (h == NULL)
1094     return false;
1095   *sym_hash = h;
1096 
1097   bed = get_elf_backend_data (abfd);
1098 
1099   /* NEW_VERSION is the symbol version of the new symbol.  */
1100   if (h->versioned != unversioned)
1101     {
1102       /* Symbol version is unknown or versioned.  */
1103       new_version = strrchr (name, ELF_VER_CHR);
1104       if (new_version)
1105 	{
1106 	  if (h->versioned == unknown)
1107 	    {
1108 	      if (new_version > name && new_version[-1] != ELF_VER_CHR)
1109 		h->versioned = versioned_hidden;
1110 	      else
1111 		h->versioned = versioned;
1112 	    }
1113 	  new_version += 1;
1114 	  if (new_version[0] == '\0')
1115 	    new_version = NULL;
1116 	}
1117       else
1118 	h->versioned = unversioned;
1119     }
1120   else
1121     new_version = NULL;
1122 
1123   /* For merging, we only care about real symbols.  But we need to make
1124      sure that indirect symbol dynamic flags are updated.  */
1125   hi = h;
1126   while (h->root.type == bfd_link_hash_indirect
1127 	 || h->root.type == bfd_link_hash_warning)
1128     h = (struct elf_link_hash_entry *) h->root.u.i.link;
1129 
1130   if (!*matched)
1131     {
1132       if (hi == h || h->root.type == bfd_link_hash_new)
1133 	*matched = true;
1134       else
1135 	{
1136 	  /* OLD_HIDDEN is true if the existing symbol is only visible
1137 	     to the symbol with the same symbol version.  NEW_HIDDEN is
1138 	     true if the new symbol is only visible to the symbol with
1139 	     the same symbol version.  */
1140 	  bool old_hidden = h->versioned == versioned_hidden;
1141 	  bool new_hidden = hi->versioned == versioned_hidden;
1142 	  if (!old_hidden && !new_hidden)
1143 	    /* The new symbol matches the existing symbol if both
1144 	       aren't hidden.  */
1145 	    *matched = true;
1146 	  else
1147 	    {
1148 	      /* OLD_VERSION is the symbol version of the existing
1149 		 symbol. */
1150 	      char *old_version;
1151 
1152 	      if (h->versioned >= versioned)
1153 		old_version = strrchr (h->root.root.string,
1154 				       ELF_VER_CHR) + 1;
1155 	      else
1156 		 old_version = NULL;
1157 
1158 	      /* The new symbol matches the existing symbol if they
1159 		 have the same symbol version.  */
1160 	      *matched = (old_version == new_version
1161 			  || (old_version != NULL
1162 			      && new_version != NULL
1163 			      && strcmp (old_version, new_version) == 0));
1164 	    }
1165 	}
1166     }
1167 
1168   /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
1169      existing symbol.  */
1170 
1171   oldbfd = NULL;
1172   oldsec = NULL;
1173   switch (h->root.type)
1174     {
1175     default:
1176       break;
1177 
1178     case bfd_link_hash_undefined:
1179     case bfd_link_hash_undefweak:
1180       oldbfd = h->root.u.undef.abfd;
1181       break;
1182 
1183     case bfd_link_hash_defined:
1184     case bfd_link_hash_defweak:
1185       oldbfd = h->root.u.def.section->owner;
1186       oldsec = h->root.u.def.section;
1187       break;
1188 
1189     case bfd_link_hash_common:
1190       oldbfd = h->root.u.c.p->section->owner;
1191       oldsec = h->root.u.c.p->section;
1192       if (pold_alignment)
1193 	*pold_alignment = h->root.u.c.p->alignment_power;
1194       break;
1195     }
1196   if (poldbfd && *poldbfd == NULL)
1197     *poldbfd = oldbfd;
1198 
1199   /* Differentiate strong and weak symbols.  */
1200   newweak = bind == STB_WEAK;
1201   oldweak = (h->root.type == bfd_link_hash_defweak
1202 	     || h->root.type == bfd_link_hash_undefweak);
1203   if (pold_weak)
1204     *pold_weak = oldweak;
1205 
1206   /* We have to check it for every instance since the first few may be
1207      references and not all compilers emit symbol type for undefined
1208      symbols.  */
1209   bfd_elf_link_mark_dynamic_symbol (info, h, sym);
1210 
1211   htab = elf_hash_table (info);
1212 
1213   /* NEWDYN and OLDDYN indicate whether the new or old symbol,
1214      respectively, is from a dynamic object.  */
1215 
1216   newdyn = (abfd->flags & DYNAMIC) != 0;
1217 
1218   /* ref_dynamic_nonweak and dynamic_def flags track actual undefined
1219      syms and defined syms in dynamic libraries respectively.
1220      ref_dynamic on the other hand can be set for a symbol defined in
1221      a dynamic library, and def_dynamic may not be set;  When the
1222      definition in a dynamic lib is overridden by a definition in the
1223      executable use of the symbol in the dynamic lib becomes a
1224      reference to the executable symbol.  */
1225   if (newdyn)
1226     {
1227       if (bfd_is_und_section (sec))
1228 	{
1229 	  if (bind != STB_WEAK)
1230 	    {
1231 	      h->ref_dynamic_nonweak = 1;
1232 	      hi->ref_dynamic_nonweak = 1;
1233 	    }
1234 	}
1235       else
1236 	{
1237 	  /* Update the existing symbol only if they match. */
1238 	  if (*matched)
1239 	    h->dynamic_def = 1;
1240 	  hi->dynamic_def = 1;
1241 	}
1242     }
1243 
1244   /* If we just created the symbol, mark it as being an ELF symbol.
1245      Other than that, there is nothing to do--there is no merge issue
1246      with a newly defined symbol--so we just return.  */
1247 
1248   if (h->root.type == bfd_link_hash_new)
1249     {
1250       h->non_elf = 0;
1251       return true;
1252     }
1253 
1254   /* In cases involving weak versioned symbols, we may wind up trying
1255      to merge a symbol with itself.  Catch that here, to avoid the
1256      confusion that results if we try to override a symbol with
1257      itself.  The additional tests catch cases like
1258      _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
1259      dynamic object, which we do want to handle here.  */
1260   if (abfd == oldbfd
1261       && (newweak || oldweak)
1262       && ((abfd->flags & DYNAMIC) == 0
1263 	  || !h->def_regular))
1264     return true;
1265 
1266   olddyn = false;
1267   if (oldbfd != NULL)
1268     olddyn = (oldbfd->flags & DYNAMIC) != 0;
1269   else if (oldsec != NULL)
1270     {
1271       /* This handles the special SHN_MIPS_{TEXT,DATA} section
1272 	 indices used by MIPS ELF.  */
1273       olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
1274     }
1275 
1276   /* Set non_ir_ref_dynamic only when not handling DT_NEEDED entries.  */
1277   if (!htab->handling_dt_needed
1278       && oldbfd != NULL
1279       && (oldbfd->flags & BFD_PLUGIN) != (abfd->flags & BFD_PLUGIN))
1280     {
1281       if (newdyn != olddyn)
1282 	{
1283 	  /* Handle a case where plugin_notice won't be called and thus
1284 	     won't set the non_ir_ref flags on the first pass over
1285 	     symbols.  */
1286 	  h->root.non_ir_ref_dynamic = true;
1287 	  hi->root.non_ir_ref_dynamic = true;
1288 	}
1289       else if ((oldbfd->flags & BFD_PLUGIN) != 0
1290 	       && hi->root.type == bfd_link_hash_indirect)
1291 	{
1292 	  /* Change indirect symbol from IR to undefined.  */
1293 	  hi->root.type = bfd_link_hash_undefined;
1294 	  hi->root.u.undef.abfd = oldbfd;
1295 	}
1296     }
1297 
1298   /* NEWDEF and OLDDEF indicate whether the new or old symbol,
1299      respectively, appear to be a definition rather than reference.  */
1300 
1301   newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
1302 
1303   olddef = (h->root.type != bfd_link_hash_undefined
1304 	    && h->root.type != bfd_link_hash_undefweak
1305 	    && h->root.type != bfd_link_hash_common);
1306 
1307   /* NEWFUNC and OLDFUNC indicate whether the new or old symbol,
1308      respectively, appear to be a function.  */
1309 
1310   newfunc = (ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1311 	     && bed->is_function_type (ELF_ST_TYPE (sym->st_info)));
1312 
1313   oldfunc = (h->type != STT_NOTYPE
1314 	     && bed->is_function_type (h->type));
1315 
1316   if (!(newfunc && oldfunc)
1317       && ELF_ST_TYPE (sym->st_info) != h->type
1318       && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1319       && h->type != STT_NOTYPE
1320       && (newdef || bfd_is_com_section (sec))
1321       && (olddef || h->root.type == bfd_link_hash_common))
1322     {
1323       /* If creating a default indirect symbol ("foo" or "foo@") from
1324 	 a dynamic versioned definition ("foo@@") skip doing so if
1325 	 there is an existing regular definition with a different
1326 	 type.  We don't want, for example, a "time" variable in the
1327 	 executable overriding a "time" function in a shared library.  */
1328       if (newdyn
1329 	  && !olddyn)
1330 	{
1331 	  *skip = true;
1332 	  return true;
1333 	}
1334 
1335       /* When adding a symbol from a regular object file after we have
1336 	 created indirect symbols, undo the indirection and any
1337 	 dynamic state.  */
1338       if (hi != h
1339 	  && !newdyn
1340 	  && olddyn)
1341 	{
1342 	  h = hi;
1343 	  (*bed->elf_backend_hide_symbol) (info, h, true);
1344 	  h->forced_local = 0;
1345 	  h->ref_dynamic = 0;
1346 	  h->def_dynamic = 0;
1347 	  h->dynamic_def = 0;
1348 	  if (h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1349 	    {
1350 	      h->root.type = bfd_link_hash_undefined;
1351 	      h->root.u.undef.abfd = abfd;
1352 	    }
1353 	  else
1354 	    {
1355 	      h->root.type = bfd_link_hash_new;
1356 	      h->root.u.undef.abfd = NULL;
1357 	    }
1358 	  return true;
1359 	}
1360     }
1361 
1362   /* Check TLS symbols.  We don't check undefined symbols introduced
1363      by "ld -u" which have no type (and oldbfd NULL), and we don't
1364      check symbols from plugins because they also have no type.  */
1365   if (oldbfd != NULL
1366       && (oldbfd->flags & BFD_PLUGIN) == 0
1367       && (abfd->flags & BFD_PLUGIN) == 0
1368       && ELF_ST_TYPE (sym->st_info) != h->type
1369       && (ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS))
1370     {
1371       bfd *ntbfd, *tbfd;
1372       bool ntdef, tdef;
1373       asection *ntsec, *tsec;
1374 
1375       if (h->type == STT_TLS)
1376 	{
1377 	  ntbfd = abfd;
1378 	  ntsec = sec;
1379 	  ntdef = newdef;
1380 	  tbfd = oldbfd;
1381 	  tsec = oldsec;
1382 	  tdef = olddef;
1383 	}
1384       else
1385 	{
1386 	  ntbfd = oldbfd;
1387 	  ntsec = oldsec;
1388 	  ntdef = olddef;
1389 	  tbfd = abfd;
1390 	  tsec = sec;
1391 	  tdef = newdef;
1392 	}
1393 
1394       if (tdef && ntdef)
1395 	_bfd_error_handler
1396 	  /* xgettext:c-format */
1397 	  (_("%s: TLS definition in %pB section %pA "
1398 	     "mismatches non-TLS definition in %pB section %pA"),
1399 	   h->root.root.string, tbfd, tsec, ntbfd, ntsec);
1400       else if (!tdef && !ntdef)
1401 	_bfd_error_handler
1402 	  /* xgettext:c-format */
1403 	  (_("%s: TLS reference in %pB "
1404 	     "mismatches non-TLS reference in %pB"),
1405 	   h->root.root.string, tbfd, ntbfd);
1406       else if (tdef)
1407 	_bfd_error_handler
1408 	  /* xgettext:c-format */
1409 	  (_("%s: TLS definition in %pB section %pA "
1410 	     "mismatches non-TLS reference in %pB"),
1411 	   h->root.root.string, tbfd, tsec, ntbfd);
1412       else
1413 	_bfd_error_handler
1414 	  /* xgettext:c-format */
1415 	  (_("%s: TLS reference in %pB "
1416 	     "mismatches non-TLS definition in %pB section %pA"),
1417 	   h->root.root.string, tbfd, ntbfd, ntsec);
1418 
1419       bfd_set_error (bfd_error_bad_value);
1420       return false;
1421     }
1422 
1423   /* If the old symbol has non-default visibility, we ignore the new
1424      definition from a dynamic object.  */
1425   if (newdyn
1426       && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1427       && !bfd_is_und_section (sec))
1428     {
1429       *skip = true;
1430       /* Make sure this symbol is dynamic.  */
1431       h->ref_dynamic = 1;
1432       hi->ref_dynamic = 1;
1433       /* A protected symbol has external availability. Make sure it is
1434 	 recorded as dynamic.
1435 
1436 	 FIXME: Should we check type and size for protected symbol?  */
1437       if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1438 	return bfd_elf_link_record_dynamic_symbol (info, h);
1439       else
1440 	return true;
1441     }
1442   else if (!newdyn
1443 	   && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1444 	   && h->def_dynamic)
1445     {
1446       /* If the new symbol with non-default visibility comes from a
1447 	 relocatable file and the old definition comes from a dynamic
1448 	 object, we remove the old definition.  */
1449       if (hi->root.type == bfd_link_hash_indirect)
1450 	{
1451 	  /* Handle the case where the old dynamic definition is
1452 	     default versioned.  We need to copy the symbol info from
1453 	     the symbol with default version to the normal one if it
1454 	     was referenced before.  */
1455 	  if (h->ref_regular)
1456 	    {
1457 	      hi->root.type = h->root.type;
1458 	      h->root.type = bfd_link_hash_indirect;
1459 	      (*bed->elf_backend_copy_indirect_symbol) (info, hi, h);
1460 
1461 	      h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1462 	      if (ELF_ST_VISIBILITY (sym->st_other) != STV_PROTECTED)
1463 		{
1464 		  /* If the new symbol is hidden or internal, completely undo
1465 		     any dynamic link state.  */
1466 		  (*bed->elf_backend_hide_symbol) (info, h, true);
1467 		  h->forced_local = 0;
1468 		  h->ref_dynamic = 0;
1469 		}
1470 	      else
1471 		h->ref_dynamic = 1;
1472 
1473 	      h->def_dynamic = 0;
1474 	      /* FIXME: Should we check type and size for protected symbol?  */
1475 	      h->size = 0;
1476 	      h->type = 0;
1477 
1478 	      h = hi;
1479 	    }
1480 	  else
1481 	    h = hi;
1482 	}
1483 
1484       /* If the old symbol was undefined before, then it will still be
1485 	 on the undefs list.  If the new symbol is undefined or
1486 	 common, we can't make it bfd_link_hash_new here, because new
1487 	 undefined or common symbols will be added to the undefs list
1488 	 by _bfd_generic_link_add_one_symbol.  Symbols may not be
1489 	 added twice to the undefs list.  Also, if the new symbol is
1490 	 undefweak then we don't want to lose the strong undef.  */
1491       if (h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1492 	{
1493 	  h->root.type = bfd_link_hash_undefined;
1494 	  h->root.u.undef.abfd = abfd;
1495 	}
1496       else
1497 	{
1498 	  h->root.type = bfd_link_hash_new;
1499 	  h->root.u.undef.abfd = NULL;
1500 	}
1501 
1502       if (ELF_ST_VISIBILITY (sym->st_other) != STV_PROTECTED)
1503 	{
1504 	  /* If the new symbol is hidden or internal, completely undo
1505 	     any dynamic link state.  */
1506 	  (*bed->elf_backend_hide_symbol) (info, h, true);
1507 	  h->forced_local = 0;
1508 	  h->ref_dynamic = 0;
1509 	}
1510       else
1511 	h->ref_dynamic = 1;
1512       h->def_dynamic = 0;
1513       /* FIXME: Should we check type and size for protected symbol?  */
1514       h->size = 0;
1515       h->type = 0;
1516       return true;
1517     }
1518 
1519   /* If a new weak symbol definition comes from a regular file and the
1520      old symbol comes from a dynamic library, we treat the new one as
1521      strong.  Similarly, an old weak symbol definition from a regular
1522      file is treated as strong when the new symbol comes from a dynamic
1523      library.  Further, an old weak symbol from a dynamic library is
1524      treated as strong if the new symbol is from a dynamic library.
1525      This reflects the way glibc's ld.so works.
1526 
1527      Also allow a weak symbol to override a linker script symbol
1528      defined by an early pass over the script.  This is done so the
1529      linker knows the symbol is defined in an object file, for the
1530      DEFINED script function.
1531 
1532      Do this before setting *type_change_ok or *size_change_ok so that
1533      we warn properly when dynamic library symbols are overridden.  */
1534 
1535   if (newdef && !newdyn && (olddyn || h->root.ldscript_def))
1536     newweak = false;
1537   if (olddef && newdyn)
1538     oldweak = false;
1539 
1540   /* Allow changes between different types of function symbol.  */
1541   if (newfunc && oldfunc)
1542     *type_change_ok = true;
1543 
1544   /* It's OK to change the type if either the existing symbol or the
1545      new symbol is weak.  A type change is also OK if the old symbol
1546      is undefined and the new symbol is defined.  */
1547 
1548   if (oldweak
1549       || newweak
1550       || (newdef
1551 	  && h->root.type == bfd_link_hash_undefined))
1552     *type_change_ok = true;
1553 
1554   /* It's OK to change the size if either the existing symbol or the
1555      new symbol is weak, or if the old symbol is undefined.  */
1556 
1557   if (*type_change_ok
1558       || h->root.type == bfd_link_hash_undefined)
1559     *size_change_ok = true;
1560 
1561   /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1562      symbol, respectively, appears to be a common symbol in a dynamic
1563      object.  If a symbol appears in an uninitialized section, and is
1564      not weak, and is not a function, then it may be a common symbol
1565      which was resolved when the dynamic object was created.  We want
1566      to treat such symbols specially, because they raise special
1567      considerations when setting the symbol size: if the symbol
1568      appears as a common symbol in a regular object, and the size in
1569      the regular object is larger, we must make sure that we use the
1570      larger size.  This problematic case can always be avoided in C,
1571      but it must be handled correctly when using Fortran shared
1572      libraries.
1573 
1574      Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1575      likewise for OLDDYNCOMMON and OLDDEF.
1576 
1577      Note that this test is just a heuristic, and that it is quite
1578      possible to have an uninitialized symbol in a shared object which
1579      is really a definition, rather than a common symbol.  This could
1580      lead to some minor confusion when the symbol really is a common
1581      symbol in some regular object.  However, I think it will be
1582      harmless.  */
1583 
1584   if (newdyn
1585       && newdef
1586       && !newweak
1587       && (sec->flags & SEC_ALLOC) != 0
1588       && (sec->flags & SEC_LOAD) == 0
1589       && sym->st_size > 0
1590       && !newfunc)
1591     newdyncommon = true;
1592   else
1593     newdyncommon = false;
1594 
1595   if (olddyn
1596       && olddef
1597       && h->root.type == bfd_link_hash_defined
1598       && h->def_dynamic
1599       && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1600       && (h->root.u.def.section->flags & SEC_LOAD) == 0
1601       && h->size > 0
1602       && !oldfunc)
1603     olddyncommon = true;
1604   else
1605     olddyncommon = false;
1606 
1607   /* We now know everything about the old and new symbols.  We ask the
1608      backend to check if we can merge them.  */
1609   if (bed->merge_symbol != NULL)
1610     {
1611       if (!bed->merge_symbol (h, sym, psec, newdef, olddef, oldbfd, oldsec))
1612 	return false;
1613       sec = *psec;
1614     }
1615 
1616   /* There are multiple definitions of a normal symbol.  Skip the
1617      default symbol as well as definition from an IR object.  */
1618   if (olddef && !olddyn && !oldweak && newdef && !newdyn && !newweak
1619       && !default_sym && h->def_regular
1620       && !(oldbfd != NULL
1621 	   && (oldbfd->flags & BFD_PLUGIN) != 0
1622 	   && (abfd->flags & BFD_PLUGIN) == 0))
1623     {
1624       /* Handle a multiple definition.  */
1625       (*info->callbacks->multiple_definition) (info, &h->root,
1626 					       abfd, sec, *pvalue);
1627       *skip = true;
1628       return true;
1629     }
1630 
1631   /* If both the old and the new symbols look like common symbols in a
1632      dynamic object, set the size of the symbol to the larger of the
1633      two.  */
1634 
1635   if (olddyncommon
1636       && newdyncommon
1637       && sym->st_size != h->size)
1638     {
1639       /* Since we think we have two common symbols, issue a multiple
1640 	 common warning if desired.  Note that we only warn if the
1641 	 size is different.  If the size is the same, we simply let
1642 	 the old symbol override the new one as normally happens with
1643 	 symbols defined in dynamic objects.  */
1644 
1645       (*info->callbacks->multiple_common) (info, &h->root, abfd,
1646 					   bfd_link_hash_common, sym->st_size);
1647       if (sym->st_size > h->size)
1648 	h->size = sym->st_size;
1649 
1650       *size_change_ok = true;
1651     }
1652 
1653   /* If we are looking at a dynamic object, and we have found a
1654      definition, we need to see if the symbol was already defined by
1655      some other object.  If so, we want to use the existing
1656      definition, and we do not want to report a multiple symbol
1657      definition error; we do this by clobbering *PSEC to be
1658      bfd_und_section_ptr.
1659 
1660      We treat a common symbol as a definition if the symbol in the
1661      shared library is a function, since common symbols always
1662      represent variables; this can cause confusion in principle, but
1663      any such confusion would seem to indicate an erroneous program or
1664      shared library.  We also permit a common symbol in a regular
1665      object to override a weak symbol in a shared object.  */
1666 
1667   if (newdyn
1668       && newdef
1669       && (olddef
1670 	  || (h->root.type == bfd_link_hash_common
1671 	      && (newweak || newfunc))))
1672     {
1673       *override = abfd;
1674       newdef = false;
1675       newdyncommon = false;
1676 
1677       *psec = sec = bfd_und_section_ptr;
1678       *size_change_ok = true;
1679 
1680       /* If we get here when the old symbol is a common symbol, then
1681 	 we are explicitly letting it override a weak symbol or
1682 	 function in a dynamic object, and we don't want to warn about
1683 	 a type change.  If the old symbol is a defined symbol, a type
1684 	 change warning may still be appropriate.  */
1685 
1686       if (h->root.type == bfd_link_hash_common)
1687 	*type_change_ok = true;
1688     }
1689 
1690   /* Handle the special case of an old common symbol merging with a
1691      new symbol which looks like a common symbol in a shared object.
1692      We change *PSEC and *PVALUE to make the new symbol look like a
1693      common symbol, and let _bfd_generic_link_add_one_symbol do the
1694      right thing.  */
1695 
1696   if (newdyncommon
1697       && h->root.type == bfd_link_hash_common)
1698     {
1699       *override = oldbfd;
1700       newdef = false;
1701       newdyncommon = false;
1702       *pvalue = sym->st_size;
1703       *psec = sec = bed->common_section (oldsec);
1704       *size_change_ok = true;
1705     }
1706 
1707   /* Skip weak definitions of symbols that are already defined.  */
1708   if (newdef && olddef && newweak)
1709     {
1710       /* Don't skip new non-IR weak syms.  */
1711       if (!(oldbfd != NULL
1712 	    && (oldbfd->flags & BFD_PLUGIN) != 0
1713 	    && (abfd->flags & BFD_PLUGIN) == 0))
1714 	{
1715 	  newdef = false;
1716 	  *skip = true;
1717 	}
1718 
1719       /* Merge st_other.  If the symbol already has a dynamic index,
1720 	 but visibility says it should not be visible, turn it into a
1721 	 local symbol.  */
1722       elf_merge_st_other (abfd, h, sym->st_other, sec, newdef, newdyn);
1723       if (h->dynindx != -1)
1724 	switch (ELF_ST_VISIBILITY (h->other))
1725 	  {
1726 	  case STV_INTERNAL:
1727 	  case STV_HIDDEN:
1728 	    (*bed->elf_backend_hide_symbol) (info, h, true);
1729 	    break;
1730 	  }
1731     }
1732 
1733   /* If the old symbol is from a dynamic object, and the new symbol is
1734      a definition which is not from a dynamic object, then the new
1735      symbol overrides the old symbol.  Symbols from regular files
1736      always take precedence over symbols from dynamic objects, even if
1737      they are defined after the dynamic object in the link.
1738 
1739      As above, we again permit a common symbol in a regular object to
1740      override a definition in a shared object if the shared object
1741      symbol is a function or is weak.  */
1742 
1743   flip = NULL;
1744   if (!newdyn
1745       && (newdef
1746 	  || (bfd_is_com_section (sec)
1747 	      && (oldweak || oldfunc)))
1748       && olddyn
1749       && olddef
1750       && h->def_dynamic)
1751     {
1752       /* Change the hash table entry to undefined, and let
1753 	 _bfd_generic_link_add_one_symbol do the right thing with the
1754 	 new definition.  */
1755 
1756       h->root.type = bfd_link_hash_undefined;
1757       h->root.u.undef.abfd = h->root.u.def.section->owner;
1758       *size_change_ok = true;
1759 
1760       olddef = false;
1761       olddyncommon = false;
1762 
1763       /* We again permit a type change when a common symbol may be
1764 	 overriding a function.  */
1765 
1766       if (bfd_is_com_section (sec))
1767 	{
1768 	  if (oldfunc)
1769 	    {
1770 	      /* If a common symbol overrides a function, make sure
1771 		 that it isn't defined dynamically nor has type
1772 		 function.  */
1773 	      h->def_dynamic = 0;
1774 	      h->type = STT_NOTYPE;
1775 	    }
1776 	  *type_change_ok = true;
1777 	}
1778 
1779       if (hi->root.type == bfd_link_hash_indirect)
1780 	flip = hi;
1781       else
1782 	/* This union may have been set to be non-NULL when this symbol
1783 	   was seen in a dynamic object.  We must force the union to be
1784 	   NULL, so that it is correct for a regular symbol.  */
1785 	h->verinfo.vertree = NULL;
1786     }
1787 
1788   /* Handle the special case of a new common symbol merging with an
1789      old symbol that looks like it might be a common symbol defined in
1790      a shared object.  Note that we have already handled the case in
1791      which a new common symbol should simply override the definition
1792      in the shared library.  */
1793 
1794   if (! newdyn
1795       && bfd_is_com_section (sec)
1796       && olddyncommon)
1797     {
1798       /* It would be best if we could set the hash table entry to a
1799 	 common symbol, but we don't know what to use for the section
1800 	 or the alignment.  */
1801       (*info->callbacks->multiple_common) (info, &h->root, abfd,
1802 					   bfd_link_hash_common, sym->st_size);
1803 
1804       /* If the presumed common symbol in the dynamic object is
1805 	 larger, pretend that the new symbol has its size.  */
1806 
1807       if (h->size > *pvalue)
1808 	*pvalue = h->size;
1809 
1810       /* We need to remember the alignment required by the symbol
1811 	 in the dynamic object.  */
1812       BFD_ASSERT (pold_alignment);
1813       *pold_alignment = h->root.u.def.section->alignment_power;
1814 
1815       olddef = false;
1816       olddyncommon = false;
1817 
1818       h->root.type = bfd_link_hash_undefined;
1819       h->root.u.undef.abfd = h->root.u.def.section->owner;
1820 
1821       *size_change_ok = true;
1822       *type_change_ok = true;
1823 
1824       if (hi->root.type == bfd_link_hash_indirect)
1825 	flip = hi;
1826       else
1827 	h->verinfo.vertree = NULL;
1828     }
1829 
1830   if (flip != NULL)
1831     {
1832       /* Handle the case where we had a versioned symbol in a dynamic
1833 	 library and now find a definition in a normal object.  In this
1834 	 case, we make the versioned symbol point to the normal one.  */
1835       flip->root.type = h->root.type;
1836       flip->root.u.undef.abfd = h->root.u.undef.abfd;
1837       h->root.type = bfd_link_hash_indirect;
1838       h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1839       (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1840       if (h->def_dynamic)
1841 	{
1842 	  h->def_dynamic = 0;
1843 	  flip->ref_dynamic = 1;
1844 	}
1845     }
1846 
1847   return true;
1848 }
1849 
1850 /* This function is called to create an indirect symbol from the
1851    default for the symbol with the default version if needed. The
1852    symbol is described by H, NAME, SYM, SEC, and VALUE.  We
1853    set DYNSYM if the new indirect symbol is dynamic.  */
1854 
1855 static bool
_bfd_elf_add_default_symbol(bfd * abfd,struct bfd_link_info * info,struct elf_link_hash_entry * h,const char * name,Elf_Internal_Sym * sym,asection * sec,bfd_vma value,bfd ** poldbfd,bool * dynsym)1856 _bfd_elf_add_default_symbol (bfd *abfd,
1857 			     struct bfd_link_info *info,
1858 			     struct elf_link_hash_entry *h,
1859 			     const char *name,
1860 			     Elf_Internal_Sym *sym,
1861 			     asection *sec,
1862 			     bfd_vma value,
1863 			     bfd **poldbfd,
1864 			     bool *dynsym)
1865 {
1866   bool type_change_ok;
1867   bool size_change_ok;
1868   bool skip;
1869   char *shortname;
1870   struct elf_link_hash_entry *hi;
1871   struct bfd_link_hash_entry *bh;
1872   const struct elf_backend_data *bed;
1873   bool collect;
1874   bool dynamic;
1875   bfd *override;
1876   char *p;
1877   size_t len, shortlen;
1878   asection *tmp_sec;
1879   bool matched;
1880 
1881   if (h->versioned == unversioned || h->versioned == versioned_hidden)
1882     return true;
1883 
1884   /* If this symbol has a version, and it is the default version, we
1885      create an indirect symbol from the default name to the fully
1886      decorated name.  This will cause external references which do not
1887      specify a version to be bound to this version of the symbol.  */
1888   p = strchr (name, ELF_VER_CHR);
1889   if (h->versioned == unknown)
1890     {
1891       if (p == NULL)
1892 	{
1893 	  h->versioned = unversioned;
1894 	  return true;
1895 	}
1896       else
1897 	{
1898 	  if (p[1] != ELF_VER_CHR)
1899 	    {
1900 	      h->versioned = versioned_hidden;
1901 	      return true;
1902 	    }
1903 	  else
1904 	    h->versioned = versioned;
1905 	}
1906     }
1907   else
1908     {
1909       /* PR ld/19073: We may see an unversioned definition after the
1910 	 default version.  */
1911       if (p == NULL)
1912 	return true;
1913     }
1914 
1915   bed = get_elf_backend_data (abfd);
1916   collect = bed->collect;
1917   dynamic = (abfd->flags & DYNAMIC) != 0;
1918 
1919   shortlen = p - name;
1920   shortname = (char *) bfd_hash_allocate (&info->hash->table, shortlen + 1);
1921   if (shortname == NULL)
1922     return false;
1923   memcpy (shortname, name, shortlen);
1924   shortname[shortlen] = '\0';
1925 
1926   /* We are going to create a new symbol.  Merge it with any existing
1927      symbol with this name.  For the purposes of the merge, act as
1928      though we were defining the symbol we just defined, although we
1929      actually going to define an indirect symbol.  */
1930   type_change_ok = false;
1931   size_change_ok = false;
1932   matched = true;
1933   tmp_sec = sec;
1934   if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &tmp_sec, &value,
1935 			      &hi, poldbfd, NULL, NULL, &skip, &override,
1936 			      &type_change_ok, &size_change_ok, &matched))
1937     return false;
1938 
1939   if (skip)
1940     goto nondefault;
1941 
1942   if (hi->def_regular || ELF_COMMON_DEF_P (hi))
1943     {
1944       /* If the undecorated symbol will have a version added by a
1945 	 script different to H, then don't indirect to/from the
1946 	 undecorated symbol.  This isn't ideal because we may not yet
1947 	 have seen symbol versions, if given by a script on the
1948 	 command line rather than via --version-script.  */
1949       if (hi->verinfo.vertree == NULL && info->version_info != NULL)
1950 	{
1951 	  bool hide;
1952 
1953 	  hi->verinfo.vertree
1954 	    = bfd_find_version_for_sym (info->version_info,
1955 					hi->root.root.string, &hide);
1956 	  if (hi->verinfo.vertree != NULL && hide)
1957 	    {
1958 	      (*bed->elf_backend_hide_symbol) (info, hi, true);
1959 	      goto nondefault;
1960 	    }
1961 	}
1962       if (hi->verinfo.vertree != NULL
1963 	  && strcmp (p + 1 + (p[1] == '@'), hi->verinfo.vertree->name) != 0)
1964 	goto nondefault;
1965     }
1966 
1967   if (! override)
1968     {
1969       /* Add the default symbol if not performing a relocatable link.  */
1970       if (! bfd_link_relocatable (info))
1971 	{
1972 	  bh = &hi->root;
1973 	  if (bh->type == bfd_link_hash_defined
1974 	      && bh->u.def.section->owner != NULL
1975 	      && (bh->u.def.section->owner->flags & BFD_PLUGIN) != 0)
1976 	    {
1977 	      /* Mark the previous definition from IR object as
1978 		 undefined so that the generic linker will override
1979 		 it.  */
1980 	      bh->type = bfd_link_hash_undefined;
1981 	      bh->u.undef.abfd = bh->u.def.section->owner;
1982 	    }
1983 	  if (! (_bfd_generic_link_add_one_symbol
1984 		 (info, abfd, shortname, BSF_INDIRECT,
1985 		  bfd_ind_section_ptr,
1986 		  0, name, false, collect, &bh)))
1987 	    return false;
1988 	  hi = (struct elf_link_hash_entry *) bh;
1989 	}
1990     }
1991   else
1992     {
1993       /* In this case the symbol named SHORTNAME is overriding the
1994 	 indirect symbol we want to add.  We were planning on making
1995 	 SHORTNAME an indirect symbol referring to NAME.  SHORTNAME
1996 	 is the name without a version.  NAME is the fully versioned
1997 	 name, and it is the default version.
1998 
1999 	 Overriding means that we already saw a definition for the
2000 	 symbol SHORTNAME in a regular object, and it is overriding
2001 	 the symbol defined in the dynamic object.
2002 
2003 	 When this happens, we actually want to change NAME, the
2004 	 symbol we just added, to refer to SHORTNAME.  This will cause
2005 	 references to NAME in the shared object to become references
2006 	 to SHORTNAME in the regular object.  This is what we expect
2007 	 when we override a function in a shared object: that the
2008 	 references in the shared object will be mapped to the
2009 	 definition in the regular object.  */
2010 
2011       while (hi->root.type == bfd_link_hash_indirect
2012 	     || hi->root.type == bfd_link_hash_warning)
2013 	hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
2014 
2015       h->root.type = bfd_link_hash_indirect;
2016       h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
2017       if (h->def_dynamic)
2018 	{
2019 	  h->def_dynamic = 0;
2020 	  hi->ref_dynamic = 1;
2021 	  if (hi->ref_regular
2022 	      || hi->def_regular)
2023 	    {
2024 	      if (! bfd_elf_link_record_dynamic_symbol (info, hi))
2025 		return false;
2026 	    }
2027 	}
2028 
2029       /* Now set HI to H, so that the following code will set the
2030 	 other fields correctly.  */
2031       hi = h;
2032     }
2033 
2034   /* Check if HI is a warning symbol.  */
2035   if (hi->root.type == bfd_link_hash_warning)
2036     hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
2037 
2038   /* If there is a duplicate definition somewhere, then HI may not
2039      point to an indirect symbol.  We will have reported an error to
2040      the user in that case.  */
2041 
2042   if (hi->root.type == bfd_link_hash_indirect)
2043     {
2044       struct elf_link_hash_entry *ht;
2045 
2046       ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
2047       (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
2048 
2049       /* If we first saw a reference to SHORTNAME with non-default
2050 	 visibility, merge that visibility to the @@VER symbol.  */
2051       elf_merge_st_other (abfd, ht, hi->other, sec, true, dynamic);
2052 
2053       /* A reference to the SHORTNAME symbol from a dynamic library
2054 	 will be satisfied by the versioned symbol at runtime.  In
2055 	 effect, we have a reference to the versioned symbol.  */
2056       ht->ref_dynamic_nonweak |= hi->ref_dynamic_nonweak;
2057       hi->dynamic_def |= ht->dynamic_def;
2058 
2059       /* See if the new flags lead us to realize that the symbol must
2060 	 be dynamic.  */
2061       if (! *dynsym)
2062 	{
2063 	  if (! dynamic)
2064 	    {
2065 	      if (! bfd_link_executable (info)
2066 		  || hi->def_dynamic
2067 		  || hi->ref_dynamic)
2068 		*dynsym = true;
2069 	    }
2070 	  else
2071 	    {
2072 	      if (hi->ref_regular)
2073 		*dynsym = true;
2074 	    }
2075 	}
2076     }
2077 
2078   /* We also need to define an indirection from the nondefault version
2079      of the symbol.  */
2080 
2081  nondefault:
2082   len = strlen (name);
2083   shortname = (char *) bfd_hash_allocate (&info->hash->table, len);
2084   if (shortname == NULL)
2085     return false;
2086   memcpy (shortname, name, shortlen);
2087   memcpy (shortname + shortlen, p + 1, len - shortlen);
2088 
2089   /* Once again, merge with any existing symbol.  */
2090   type_change_ok = false;
2091   size_change_ok = false;
2092   tmp_sec = sec;
2093   if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &tmp_sec, &value,
2094 			      &hi, poldbfd, NULL, NULL, &skip, &override,
2095 			      &type_change_ok, &size_change_ok, &matched))
2096     return false;
2097 
2098   if (skip)
2099     {
2100       if (!dynamic
2101 	  && h->root.type == bfd_link_hash_defweak
2102 	  && hi->root.type == bfd_link_hash_defined)
2103 	{
2104 	  /* We are handling a weak sym@@ver and attempting to define
2105 	     a weak sym@ver, but _bfd_elf_merge_symbol said to skip the
2106 	     new weak sym@ver because there is already a strong sym@ver.
2107 	     However, sym@ver and sym@@ver are really the same symbol.
2108 	     The existing strong sym@ver ought to override sym@@ver.  */
2109 	  h->root.type = bfd_link_hash_defined;
2110 	  h->root.u.def.section = hi->root.u.def.section;
2111 	  h->root.u.def.value = hi->root.u.def.value;
2112 	  hi->root.type = bfd_link_hash_indirect;
2113 	  hi->root.u.i.link = &h->root;
2114 	}
2115       else
2116 	return true;
2117     }
2118   else if (override)
2119     {
2120       /* Here SHORTNAME is a versioned name, so we don't expect to see
2121 	 the type of override we do in the case above unless it is
2122 	 overridden by a versioned definition.  */
2123       if (hi->root.type != bfd_link_hash_defined
2124 	  && hi->root.type != bfd_link_hash_defweak)
2125 	_bfd_error_handler
2126 	  /* xgettext:c-format */
2127 	  (_("%pB: unexpected redefinition of indirect versioned symbol `%s'"),
2128 	   abfd, shortname);
2129       return true;
2130     }
2131   else
2132     {
2133       bh = &hi->root;
2134       if (! (_bfd_generic_link_add_one_symbol
2135 	     (info, abfd, shortname, BSF_INDIRECT,
2136 	      bfd_ind_section_ptr, 0, name, false, collect, &bh)))
2137 	return false;
2138       hi = (struct elf_link_hash_entry *) bh;
2139     }
2140 
2141   /* If there is a duplicate definition somewhere, then HI may not
2142      point to an indirect symbol.  We will have reported an error
2143      to the user in that case.  */
2144   if (hi->root.type == bfd_link_hash_indirect)
2145     {
2146       (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
2147       h->ref_dynamic_nonweak |= hi->ref_dynamic_nonweak;
2148       hi->dynamic_def |= h->dynamic_def;
2149 
2150       /* If we first saw a reference to @VER symbol with
2151 	 non-default visibility, merge that visibility to the
2152 	 @@VER symbol.  */
2153       elf_merge_st_other (abfd, h, hi->other, sec, true, dynamic);
2154 
2155       /* See if the new flags lead us to realize that the symbol
2156 	 must be dynamic.  */
2157       if (! *dynsym)
2158 	{
2159 	  if (! dynamic)
2160 	    {
2161 	      if (! bfd_link_executable (info)
2162 		  || hi->ref_dynamic)
2163 		*dynsym = true;
2164 	    }
2165 	  else
2166 	    {
2167 	      if (hi->ref_regular)
2168 		*dynsym = true;
2169 	    }
2170 	}
2171     }
2172 
2173   return true;
2174 }
2175 
2176 /* This routine is used to export all defined symbols into the dynamic
2177    symbol table.  It is called via elf_link_hash_traverse.  */
2178 
2179 static bool
_bfd_elf_export_symbol(struct elf_link_hash_entry * h,void * data)2180 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
2181 {
2182   struct elf_info_failed *eif = (struct elf_info_failed *) data;
2183 
2184   /* Ignore indirect symbols.  These are added by the versioning code.  */
2185   if (h->root.type == bfd_link_hash_indirect)
2186     return true;
2187 
2188   /* Ignore this if we won't export it.  */
2189   if (!eif->info->export_dynamic && !h->dynamic)
2190     return true;
2191 
2192   if (h->dynindx == -1
2193       && (h->def_regular || h->ref_regular)
2194       && ! bfd_hide_sym_by_version (eif->info->version_info,
2195 				    h->root.root.string))
2196     {
2197       if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2198 	{
2199 	  eif->failed = true;
2200 	  return false;
2201 	}
2202     }
2203 
2204   return true;
2205 }
2206 
2207 /* Return the glibc version reference if VERSION_DEP is added to the
2208    list of glibc version dependencies successfully.  VERSION_DEP will
2209    be put into the .gnu.version_r section.  */
2210 
2211 static Elf_Internal_Verneed *
elf_link_add_glibc_verneed(struct elf_find_verdep_info * rinfo,Elf_Internal_Verneed * glibc_verref,const char * version_dep)2212 elf_link_add_glibc_verneed (struct elf_find_verdep_info *rinfo,
2213 			    Elf_Internal_Verneed *glibc_verref,
2214 			    const char *version_dep)
2215 {
2216   Elf_Internal_Verneed *t;
2217   Elf_Internal_Vernaux *a;
2218   size_t amt;
2219 
2220   if (glibc_verref != NULL)
2221     {
2222       t = glibc_verref;
2223 
2224       for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2225 	{
2226 	  /* Return if VERSION_DEP dependency has been added.  */
2227 	  if (a->vna_nodename == version_dep
2228 	      || strcmp (a->vna_nodename, version_dep) == 0)
2229 	    return t;
2230 	}
2231     }
2232   else
2233     {
2234       bool is_glibc;
2235 
2236       for (t = elf_tdata (rinfo->info->output_bfd)->verref;
2237 	   t != NULL;
2238 	   t = t->vn_nextref)
2239 	{
2240 	  const char *soname = bfd_elf_get_dt_soname (t->vn_bfd);
2241 	  if (soname != NULL && startswith (soname, "libc.so."))
2242 	    break;
2243 	}
2244 
2245       /* Skip the shared library if it isn't libc.so.  */
2246       if (t == NULL)
2247 	return t;
2248 
2249       is_glibc = false;
2250       for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2251 	{
2252 	  /* Return if VERSION_DEP dependency has been added.  */
2253 	  if (a->vna_nodename == version_dep
2254 	      || strcmp (a->vna_nodename, version_dep) == 0)
2255 	    return t;
2256 
2257 	  /* Check if libc.so provides GLIBC_2.XX version.  */
2258 	  if (!is_glibc && startswith (a->vna_nodename, "GLIBC_2."))
2259 	    is_glibc = true;
2260 	}
2261 
2262       /* Skip if it isn't linked against glibc.  */
2263       if (!is_glibc)
2264 	return NULL;
2265     }
2266 
2267   amt = sizeof *a;
2268   a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->info->output_bfd, amt);
2269   if (a == NULL)
2270     {
2271       rinfo->failed = true;
2272       return NULL;
2273     }
2274 
2275   a->vna_nodename = version_dep;
2276   a->vna_flags = 0;
2277   a->vna_nextptr = t->vn_auxptr;
2278   a->vna_other = rinfo->vers + 1;
2279   ++rinfo->vers;
2280 
2281   t->vn_auxptr = a;
2282 
2283   return t;
2284 }
2285 
2286 /* Add VERSION_DEP to the list of version dependencies when linked
2287    against glibc.  */
2288 
2289 void
_bfd_elf_link_add_glibc_version_dependency(struct elf_find_verdep_info * rinfo,const char * version_dep[])2290 _bfd_elf_link_add_glibc_version_dependency
2291   (struct elf_find_verdep_info *rinfo,
2292    const char *version_dep[])
2293 {
2294   Elf_Internal_Verneed *t = NULL;
2295 
2296   do
2297     {
2298       t = elf_link_add_glibc_verneed (rinfo, t, *version_dep);
2299       /* Return if there is no glibc version reference.  */
2300       if (t == NULL)
2301 	return;
2302       version_dep++;
2303     }
2304   while (*version_dep != NULL);
2305 }
2306 
2307 /* Add GLIBC_ABI_DT_RELR to the list of version dependencies when
2308    linked against glibc.  */
2309 
2310 void
_bfd_elf_link_add_dt_relr_dependency(struct elf_find_verdep_info * rinfo)2311 _bfd_elf_link_add_dt_relr_dependency (struct elf_find_verdep_info *rinfo)
2312 {
2313   if (rinfo->info->enable_dt_relr)
2314     {
2315       const char *version[] =
2316 	{
2317 	  "GLIBC_ABI_DT_RELR",
2318 	  NULL
2319 	};
2320       _bfd_elf_link_add_glibc_version_dependency (rinfo, version);
2321     }
2322 }
2323 
2324 /* Look through the symbols which are defined in other shared
2325    libraries and referenced here.  Update the list of version
2326    dependencies.  This will be put into the .gnu.version_r section.
2327    This function is called via elf_link_hash_traverse.  */
2328 
2329 static bool
_bfd_elf_link_find_version_dependencies(struct elf_link_hash_entry * h,void * data)2330 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
2331 					 void *data)
2332 {
2333   struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
2334   Elf_Internal_Verneed *t;
2335   Elf_Internal_Vernaux *a;
2336   size_t amt;
2337 
2338   /* We only care about symbols defined in shared objects with version
2339      information.  */
2340   if (!h->def_dynamic
2341       || h->def_regular
2342       || h->dynindx == -1
2343       || h->verinfo.verdef == NULL
2344       || (elf_dyn_lib_class (h->verinfo.verdef->vd_bfd)
2345 	  & (DYN_AS_NEEDED | DYN_DT_NEEDED | DYN_NO_NEEDED)))
2346     return true;
2347 
2348   /* See if we already know about this version.  */
2349   for (t = elf_tdata (rinfo->info->output_bfd)->verref;
2350        t != NULL;
2351        t = t->vn_nextref)
2352     {
2353       if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
2354 	continue;
2355 
2356       for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2357 	if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
2358 	  return true;
2359 
2360       break;
2361     }
2362 
2363   /* This is a new version.  Add it to tree we are building.  */
2364 
2365   if (t == NULL)
2366     {
2367       amt = sizeof *t;
2368       t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->info->output_bfd, amt);
2369       if (t == NULL)
2370 	{
2371 	  rinfo->failed = true;
2372 	  return false;
2373 	}
2374 
2375       t->vn_bfd = h->verinfo.verdef->vd_bfd;
2376       t->vn_nextref = elf_tdata (rinfo->info->output_bfd)->verref;
2377       elf_tdata (rinfo->info->output_bfd)->verref = t;
2378     }
2379 
2380   amt = sizeof *a;
2381   a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->info->output_bfd, amt);
2382   if (a == NULL)
2383     {
2384       rinfo->failed = true;
2385       return false;
2386     }
2387 
2388   /* Note that we are copying a string pointer here, and testing it
2389      above.  If bfd_elf_string_from_elf_section is ever changed to
2390      discard the string data when low in memory, this will have to be
2391      fixed.  */
2392   a->vna_nodename = h->verinfo.verdef->vd_nodename;
2393 
2394   a->vna_flags = h->verinfo.verdef->vd_flags;
2395   a->vna_nextptr = t->vn_auxptr;
2396 
2397   h->verinfo.verdef->vd_exp_refno = rinfo->vers;
2398   ++rinfo->vers;
2399 
2400   a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
2401 
2402   t->vn_auxptr = a;
2403 
2404   return true;
2405 }
2406 
2407 /* Return TRUE and set *HIDE to TRUE if the versioned symbol is
2408    hidden.  Set *T_P to NULL if there is no match.  */
2409 
2410 static bool
_bfd_elf_link_hide_versioned_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,const char * version_p,struct bfd_elf_version_tree ** t_p,bool * hide)2411 _bfd_elf_link_hide_versioned_symbol (struct bfd_link_info *info,
2412 				     struct elf_link_hash_entry *h,
2413 				     const char *version_p,
2414 				     struct bfd_elf_version_tree **t_p,
2415 				     bool *hide)
2416 {
2417   struct bfd_elf_version_tree *t;
2418 
2419   /* Look for the version.  If we find it, it is no longer weak.  */
2420   for (t = info->version_info; t != NULL; t = t->next)
2421     {
2422       if (strcmp (t->name, version_p) == 0)
2423 	{
2424 	  size_t len;
2425 	  char *alc;
2426 	  struct bfd_elf_version_expr *d;
2427 
2428 	  len = version_p - h->root.root.string;
2429 	  alc = (char *) bfd_malloc (len);
2430 	  if (alc == NULL)
2431 	    return false;
2432 	  memcpy (alc, h->root.root.string, len - 1);
2433 	  alc[len - 1] = '\0';
2434 	  if (alc[len - 2] == ELF_VER_CHR)
2435 	    alc[len - 2] = '\0';
2436 
2437 	  h->verinfo.vertree = t;
2438 	  t->used = true;
2439 	  d = NULL;
2440 
2441 	  if (t->globals.list != NULL)
2442 	    d = (*t->match) (&t->globals, NULL, alc);
2443 
2444 	  /* See if there is anything to force this symbol to
2445 	     local scope.  */
2446 	  if (d == NULL && t->locals.list != NULL)
2447 	    {
2448 	      d = (*t->match) (&t->locals, NULL, alc);
2449 	      if (d != NULL
2450 		  && h->dynindx != -1
2451 		  && ! info->export_dynamic)
2452 		*hide = true;
2453 	    }
2454 
2455 	  free (alc);
2456 	  break;
2457 	}
2458     }
2459 
2460   *t_p = t;
2461 
2462   return true;
2463 }
2464 
2465 /* Return TRUE if the symbol H is hidden by version script.  */
2466 
2467 bool
_bfd_elf_link_hide_sym_by_version(struct bfd_link_info * info,struct elf_link_hash_entry * h)2468 _bfd_elf_link_hide_sym_by_version (struct bfd_link_info *info,
2469 				   struct elf_link_hash_entry *h)
2470 {
2471   const char *p;
2472   bool hide = false;
2473   const struct elf_backend_data *bed
2474     = get_elf_backend_data (info->output_bfd);
2475 
2476   /* Version script only hides symbols defined in regular objects.  */
2477   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
2478     return true;
2479 
2480   p = strchr (h->root.root.string, ELF_VER_CHR);
2481   if (p != NULL && h->verinfo.vertree == NULL)
2482     {
2483       struct bfd_elf_version_tree *t;
2484 
2485       ++p;
2486       if (*p == ELF_VER_CHR)
2487 	++p;
2488 
2489       if (*p != '\0'
2490 	  && _bfd_elf_link_hide_versioned_symbol (info, h, p, &t, &hide)
2491 	  && hide)
2492 	{
2493 	  if (hide)
2494 	    (*bed->elf_backend_hide_symbol) (info, h, true);
2495 	  return true;
2496 	}
2497     }
2498 
2499   /* If we don't have a version for this symbol, see if we can find
2500      something.  */
2501   if (h->verinfo.vertree == NULL && info->version_info != NULL)
2502     {
2503       h->verinfo.vertree
2504 	= bfd_find_version_for_sym (info->version_info,
2505 				    h->root.root.string, &hide);
2506       if (h->verinfo.vertree != NULL && hide)
2507 	{
2508 	  (*bed->elf_backend_hide_symbol) (info, h, true);
2509 	  return true;
2510 	}
2511     }
2512 
2513   return false;
2514 }
2515 
2516 /* Figure out appropriate versions for all the symbols.  We may not
2517    have the version number script until we have read all of the input
2518    files, so until that point we don't know which symbols should be
2519    local.  This function is called via elf_link_hash_traverse.  */
2520 
2521 static bool
_bfd_elf_link_assign_sym_version(struct elf_link_hash_entry * h,void * data)2522 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
2523 {
2524   struct elf_info_failed *sinfo;
2525   struct bfd_link_info *info;
2526   const struct elf_backend_data *bed;
2527   struct elf_info_failed eif;
2528   char *p;
2529   bool hide;
2530 
2531   sinfo = (struct elf_info_failed *) data;
2532   info = sinfo->info;
2533 
2534   /* Fix the symbol flags.  */
2535   eif.failed = false;
2536   eif.info = info;
2537   if (! _bfd_elf_fix_symbol_flags (h, &eif))
2538     {
2539       if (eif.failed)
2540 	sinfo->failed = true;
2541       return false;
2542     }
2543 
2544   bed = get_elf_backend_data (info->output_bfd);
2545 
2546   /* We only need version numbers for symbols defined in regular
2547      objects.  */
2548   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
2549     {
2550       /* Hide symbols defined in discarded input sections.  */
2551       if ((h->root.type == bfd_link_hash_defined
2552 	   || h->root.type == bfd_link_hash_defweak)
2553 	  && discarded_section (h->root.u.def.section))
2554 	(*bed->elf_backend_hide_symbol) (info, h, true);
2555       return true;
2556     }
2557 
2558   hide = false;
2559   p = strchr (h->root.root.string, ELF_VER_CHR);
2560   if (p != NULL && h->verinfo.vertree == NULL)
2561     {
2562       struct bfd_elf_version_tree *t;
2563 
2564       ++p;
2565       if (*p == ELF_VER_CHR)
2566 	++p;
2567 
2568       /* If there is no version string, we can just return out.  */
2569       if (*p == '\0')
2570 	return true;
2571 
2572       if (!_bfd_elf_link_hide_versioned_symbol (info, h, p, &t, &hide))
2573 	{
2574 	  sinfo->failed = true;
2575 	  return false;
2576 	}
2577 
2578       if (hide)
2579 	(*bed->elf_backend_hide_symbol) (info, h, true);
2580 
2581       /* If we are building an application, we need to create a
2582 	 version node for this version.  */
2583       if (t == NULL && bfd_link_executable (info))
2584 	{
2585 	  struct bfd_elf_version_tree **pp;
2586 	  int version_index;
2587 
2588 	  /* If we aren't going to export this symbol, we don't need
2589 	     to worry about it.  */
2590 	  if (h->dynindx == -1)
2591 	    return true;
2592 
2593 	  t = (struct bfd_elf_version_tree *) bfd_zalloc (info->output_bfd,
2594 							  sizeof *t);
2595 	  if (t == NULL)
2596 	    {
2597 	      sinfo->failed = true;
2598 	      return false;
2599 	    }
2600 
2601 	  t->name = p;
2602 	  t->name_indx = (unsigned int) -1;
2603 	  t->used = true;
2604 
2605 	  version_index = 1;
2606 	  /* Don't count anonymous version tag.  */
2607 	  if (sinfo->info->version_info != NULL
2608 	      && sinfo->info->version_info->vernum == 0)
2609 	    version_index = 0;
2610 	  for (pp = &sinfo->info->version_info;
2611 	       *pp != NULL;
2612 	       pp = &(*pp)->next)
2613 	    ++version_index;
2614 	  t->vernum = version_index;
2615 
2616 	  *pp = t;
2617 
2618 	  h->verinfo.vertree = t;
2619 	}
2620       else if (t == NULL)
2621 	{
2622 	  /* We could not find the version for a symbol when
2623 	     generating a shared archive.  Return an error.  */
2624 	  _bfd_error_handler
2625 	    /* xgettext:c-format */
2626 	    (_("%pB: version node not found for symbol %s"),
2627 	     info->output_bfd, h->root.root.string);
2628 	  bfd_set_error (bfd_error_bad_value);
2629 	  sinfo->failed = true;
2630 	  return false;
2631 	}
2632     }
2633 
2634   /* If we don't have a version for this symbol, see if we can find
2635      something.  */
2636   if (!hide
2637       && h->verinfo.vertree == NULL
2638       && sinfo->info->version_info != NULL)
2639     {
2640       h->verinfo.vertree
2641 	= bfd_find_version_for_sym (sinfo->info->version_info,
2642 				    h->root.root.string, &hide);
2643       if (h->verinfo.vertree != NULL && hide)
2644 	(*bed->elf_backend_hide_symbol) (info, h, true);
2645     }
2646 
2647   return true;
2648 }
2649 
2650 /* Read and swap the relocs from the section indicated by SHDR.  This
2651    may be either a REL or a RELA section.  The relocations are
2652    translated into RELA relocations and stored in INTERNAL_RELOCS,
2653    which should have already been allocated to contain enough space.
2654    The EXTERNAL_RELOCS are a buffer where the external form of the
2655    relocations should be stored.
2656 
2657    Returns FALSE if something goes wrong.  */
2658 
2659 static bool
elf_link_read_relocs_from_section(bfd * abfd,asection * sec,Elf_Internal_Shdr * shdr,void * external_relocs,Elf_Internal_Rela * internal_relocs)2660 elf_link_read_relocs_from_section (bfd *abfd,
2661 				   asection *sec,
2662 				   Elf_Internal_Shdr *shdr,
2663 				   void *external_relocs,
2664 				   Elf_Internal_Rela *internal_relocs)
2665 {
2666   const struct elf_backend_data *bed;
2667   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
2668   const bfd_byte *erela;
2669   const bfd_byte *erelaend;
2670   Elf_Internal_Rela *irela;
2671   Elf_Internal_Shdr *symtab_hdr;
2672   size_t nsyms;
2673 
2674   /* Position ourselves at the start of the section.  */
2675   if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2676     return false;
2677 
2678   /* Read the relocations.  */
2679   if (bfd_read (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
2680     return false;
2681 
2682   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2683   nsyms = NUM_SHDR_ENTRIES (symtab_hdr);
2684 
2685   bed = get_elf_backend_data (abfd);
2686 
2687   /* Convert the external relocations to the internal format.  */
2688   if (shdr->sh_entsize == bed->s->sizeof_rel)
2689     swap_in = bed->s->swap_reloc_in;
2690   else if (shdr->sh_entsize == bed->s->sizeof_rela)
2691     swap_in = bed->s->swap_reloca_in;
2692   else
2693     {
2694       bfd_set_error (bfd_error_wrong_format);
2695       return false;
2696     }
2697 
2698   erela = (const bfd_byte *) external_relocs;
2699   /* Setting erelaend like this and comparing with <= handles case of
2700      a fuzzed object with sh_size not a multiple of sh_entsize.  */
2701   erelaend = erela + shdr->sh_size - shdr->sh_entsize;
2702   irela = internal_relocs;
2703   while (erela <= erelaend)
2704     {
2705       bfd_vma r_symndx;
2706 
2707       (*swap_in) (abfd, erela, irela);
2708       r_symndx = ELF32_R_SYM (irela->r_info);
2709       if (bed->s->arch_size == 64)
2710 	r_symndx >>= 24;
2711       if (nsyms > 0)
2712 	{
2713 	  if ((size_t) r_symndx >= nsyms)
2714 	    {
2715 	      _bfd_error_handler
2716 		/* xgettext:c-format */
2717 		(_("%pB: bad reloc symbol index (%#" PRIx64 " >= %#lx)"
2718 		   " for offset %#" PRIx64 " in section `%pA'"),
2719 		 abfd, (uint64_t) r_symndx, (unsigned long) nsyms,
2720 		 (uint64_t) irela->r_offset, sec);
2721 	      bfd_set_error (bfd_error_bad_value);
2722 	      return false;
2723 	    }
2724 	}
2725       else if (r_symndx != STN_UNDEF)
2726 	{
2727 	  _bfd_error_handler
2728 	    /* xgettext:c-format */
2729 	    (_("%pB: non-zero symbol index (%#" PRIx64 ")"
2730 	       " for offset %#" PRIx64 " in section `%pA'"
2731 	       " when the object file has no symbol table"),
2732 	     abfd, (uint64_t) r_symndx,
2733 	     (uint64_t) irela->r_offset, sec);
2734 	  bfd_set_error (bfd_error_bad_value);
2735 	  return false;
2736 	}
2737       irela += bed->s->int_rels_per_ext_rel;
2738       erela += shdr->sh_entsize;
2739     }
2740 
2741   return true;
2742 }
2743 
2744 /* Read and swap the relocs for a section O.  They may have been
2745    cached.  If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2746    not NULL, they are used as buffers to read into.  They are known to
2747    be large enough.  If the INTERNAL_RELOCS relocs argument is NULL,
2748    the return value is allocated using either malloc or bfd_alloc,
2749    according to the KEEP_MEMORY argument.  If O has two relocation
2750    sections (both REL and RELA relocations), then the REL_HDR
2751    relocations will appear first in INTERNAL_RELOCS, followed by the
2752    RELA_HDR relocations.  If INFO isn't NULL and KEEP_MEMORY is true,
2753    update cache_size.  */
2754 
2755 Elf_Internal_Rela *
_bfd_elf_link_info_read_relocs(bfd * abfd,struct bfd_link_info * info,asection * o,void * external_relocs,Elf_Internal_Rela * internal_relocs,bool keep_memory)2756 _bfd_elf_link_info_read_relocs (bfd *abfd,
2757 				struct bfd_link_info *info,
2758 				asection *o,
2759 				void *external_relocs,
2760 				Elf_Internal_Rela *internal_relocs,
2761 				bool keep_memory)
2762 {
2763   void *alloc1 = NULL;
2764   Elf_Internal_Rela *alloc2 = NULL;
2765   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2766   struct bfd_elf_section_data *esdo = elf_section_data (o);
2767   Elf_Internal_Rela *internal_rela_relocs;
2768 
2769   if (esdo->relocs != NULL)
2770     return esdo->relocs;
2771 
2772   if (o->reloc_count == 0)
2773     return NULL;
2774 
2775   if (internal_relocs == NULL)
2776     {
2777       bfd_size_type size;
2778 
2779       size = (bfd_size_type) o->reloc_count * sizeof (Elf_Internal_Rela);
2780       if (keep_memory)
2781 	{
2782 	  internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2783 	  if (info)
2784 	    info->cache_size += size;
2785 	}
2786       else
2787 	internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2788       if (internal_relocs == NULL)
2789 	goto error_return;
2790     }
2791 
2792   if (external_relocs == NULL)
2793     {
2794       bfd_size_type size = 0;
2795 
2796       if (esdo->rel.hdr)
2797 	size += esdo->rel.hdr->sh_size;
2798       if (esdo->rela.hdr)
2799 	size += esdo->rela.hdr->sh_size;
2800 
2801       alloc1 = bfd_malloc (size);
2802       if (alloc1 == NULL)
2803 	goto error_return;
2804       external_relocs = alloc1;
2805     }
2806 
2807   internal_rela_relocs = internal_relocs;
2808   if (esdo->rel.hdr)
2809     {
2810       if (!elf_link_read_relocs_from_section (abfd, o, esdo->rel.hdr,
2811 					      external_relocs,
2812 					      internal_relocs))
2813 	goto error_return;
2814       external_relocs = (((bfd_byte *) external_relocs)
2815 			 + esdo->rel.hdr->sh_size);
2816       internal_rela_relocs += (NUM_SHDR_ENTRIES (esdo->rel.hdr)
2817 			       * bed->s->int_rels_per_ext_rel);
2818     }
2819 
2820   if (esdo->rela.hdr
2821       && (!elf_link_read_relocs_from_section (abfd, o, esdo->rela.hdr,
2822 					      external_relocs,
2823 					      internal_rela_relocs)))
2824     goto error_return;
2825 
2826   /* Cache the results for next time, if we can.  */
2827   if (keep_memory)
2828     esdo->relocs = internal_relocs;
2829 
2830   free (alloc1);
2831 
2832   /* Don't free alloc2, since if it was allocated we are passing it
2833      back (under the name of internal_relocs).  */
2834 
2835   return internal_relocs;
2836 
2837  error_return:
2838   free (alloc1);
2839   if (alloc2 != NULL)
2840     {
2841       if (keep_memory)
2842 	bfd_release (abfd, alloc2);
2843       else
2844 	free (alloc2);
2845     }
2846   return NULL;
2847 }
2848 
2849 /* This is similar to _bfd_elf_link_info_read_relocs, except for that
2850    NULL is passed to _bfd_elf_link_info_read_relocs for pointer to
2851    struct bfd_link_info.  */
2852 
2853 Elf_Internal_Rela *
_bfd_elf_link_read_relocs(bfd * abfd,asection * o,void * external_relocs,Elf_Internal_Rela * internal_relocs,bool keep_memory)2854 _bfd_elf_link_read_relocs (bfd *abfd,
2855 			   asection *o,
2856 			   void *external_relocs,
2857 			   Elf_Internal_Rela *internal_relocs,
2858 			   bool keep_memory)
2859 {
2860   return _bfd_elf_link_info_read_relocs (abfd, NULL, o, external_relocs,
2861 					 internal_relocs, keep_memory);
2862 
2863 }
2864 
2865 /* Compute the size of, and allocate space for, REL_HDR which is the
2866    section header for a section containing relocations for O.  */
2867 
2868 static bool
_bfd_elf_link_size_reloc_section(bfd * abfd,struct bfd_elf_section_reloc_data * reldata)2869 _bfd_elf_link_size_reloc_section (bfd *abfd,
2870 				  struct bfd_elf_section_reloc_data *reldata)
2871 {
2872   Elf_Internal_Shdr *rel_hdr = reldata->hdr;
2873 
2874   /* That allows us to calculate the size of the section.  */
2875   rel_hdr->sh_size = rel_hdr->sh_entsize * reldata->count;
2876 
2877   /* The contents field must last into write_object_contents, so we
2878      allocate it with bfd_alloc rather than malloc.  Also since we
2879      cannot be sure that the contents will actually be filled in,
2880      we zero the allocated space.  */
2881   rel_hdr->contents = (unsigned char *) bfd_zalloc (abfd, rel_hdr->sh_size);
2882   if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2883     return false;
2884 
2885   if (reldata->hashes == NULL && reldata->count)
2886     {
2887       struct elf_link_hash_entry **p;
2888 
2889       p = ((struct elf_link_hash_entry **)
2890 	   bfd_zmalloc (reldata->count * sizeof (*p)));
2891       if (p == NULL)
2892 	return false;
2893 
2894       reldata->hashes = p;
2895     }
2896 
2897   return true;
2898 }
2899 
2900 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2901    originated from the section given by INPUT_REL_HDR) to the
2902    OUTPUT_BFD.  */
2903 
2904 bool
_bfd_elf_link_output_relocs(bfd * output_bfd,asection * input_section,Elf_Internal_Shdr * input_rel_hdr,Elf_Internal_Rela * internal_relocs,struct elf_link_hash_entry ** rel_hash ATTRIBUTE_UNUSED)2905 _bfd_elf_link_output_relocs (bfd *output_bfd,
2906 			     asection *input_section,
2907 			     Elf_Internal_Shdr *input_rel_hdr,
2908 			     Elf_Internal_Rela *internal_relocs,
2909 			     struct elf_link_hash_entry **rel_hash
2910 			       ATTRIBUTE_UNUSED)
2911 {
2912   Elf_Internal_Rela *irela;
2913   Elf_Internal_Rela *irelaend;
2914   bfd_byte *erel;
2915   struct bfd_elf_section_reloc_data *output_reldata;
2916   asection *output_section;
2917   const struct elf_backend_data *bed;
2918   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2919   struct bfd_elf_section_data *esdo;
2920 
2921   output_section = input_section->output_section;
2922 
2923   bed = get_elf_backend_data (output_bfd);
2924   esdo = elf_section_data (output_section);
2925   if (esdo->rel.hdr && esdo->rel.hdr->sh_entsize == input_rel_hdr->sh_entsize)
2926     {
2927       output_reldata = &esdo->rel;
2928       swap_out = bed->s->swap_reloc_out;
2929     }
2930   else if (esdo->rela.hdr
2931 	   && esdo->rela.hdr->sh_entsize == input_rel_hdr->sh_entsize)
2932     {
2933       output_reldata = &esdo->rela;
2934       swap_out = bed->s->swap_reloca_out;
2935     }
2936   else
2937     {
2938       _bfd_error_handler
2939 	/* xgettext:c-format */
2940 	(_("%pB: relocation size mismatch in %pB section %pA"),
2941 	 output_bfd, input_section->owner, input_section);
2942       bfd_set_error (bfd_error_wrong_format);
2943       return false;
2944     }
2945 
2946   erel = output_reldata->hdr->contents;
2947   erel += output_reldata->count * input_rel_hdr->sh_entsize;
2948   irela = internal_relocs;
2949   irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2950 		      * bed->s->int_rels_per_ext_rel);
2951   while (irela < irelaend)
2952     {
2953       (*swap_out) (output_bfd, irela, erel);
2954       irela += bed->s->int_rels_per_ext_rel;
2955       erel += input_rel_hdr->sh_entsize;
2956     }
2957 
2958   /* Bump the counter, so that we know where to add the next set of
2959      relocations.  */
2960   output_reldata->count += NUM_SHDR_ENTRIES (input_rel_hdr);
2961 
2962   return true;
2963 }
2964 
2965 /* Make weak undefined symbols in PIE dynamic.  */
2966 
2967 bool
_bfd_elf_link_hash_fixup_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)2968 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2969 				 struct elf_link_hash_entry *h)
2970 {
2971   if (bfd_link_pie (info)
2972       && h->dynindx == -1
2973       && h->root.type == bfd_link_hash_undefweak)
2974     return bfd_elf_link_record_dynamic_symbol (info, h);
2975 
2976   return true;
2977 }
2978 
2979 /* Fix up the flags for a symbol.  This handles various cases which
2980    can only be fixed after all the input files are seen.  This is
2981    currently called by both adjust_dynamic_symbol and
2982    assign_sym_version, which is unnecessary but perhaps more robust in
2983    the face of future changes.  */
2984 
2985 static bool
_bfd_elf_fix_symbol_flags(struct elf_link_hash_entry * h,struct elf_info_failed * eif)2986 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2987 			   struct elf_info_failed *eif)
2988 {
2989   const struct elf_backend_data *bed;
2990 
2991   /* If this symbol was mentioned in a non-ELF file, try to set
2992      DEF_REGULAR and REF_REGULAR correctly.  This is the only way to
2993      permit a non-ELF file to correctly refer to a symbol defined in
2994      an ELF dynamic object.  */
2995   if (h->non_elf)
2996     {
2997       while (h->root.type == bfd_link_hash_indirect)
2998 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
2999 
3000       if (h->root.type != bfd_link_hash_defined
3001 	  && h->root.type != bfd_link_hash_defweak)
3002 	{
3003 	  h->ref_regular = 1;
3004 	  h->ref_regular_nonweak = 1;
3005 	}
3006       else
3007 	{
3008 	  if (h->root.u.def.section->owner != NULL
3009 	      && (bfd_get_flavour (h->root.u.def.section->owner)
3010 		  == bfd_target_elf_flavour))
3011 	    {
3012 	      h->ref_regular = 1;
3013 	      h->ref_regular_nonweak = 1;
3014 	    }
3015 	  else
3016 	    h->def_regular = 1;
3017 	}
3018 
3019       if (h->dynindx == -1
3020 	  && (h->def_dynamic
3021 	      || h->ref_dynamic))
3022 	{
3023 	  if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
3024 	    {
3025 	      eif->failed = true;
3026 	      return false;
3027 	    }
3028 	}
3029     }
3030   else
3031     {
3032       /* Unfortunately, NON_ELF is only correct if the symbol
3033 	 was first seen in a non-ELF file.  Fortunately, if the symbol
3034 	 was first seen in an ELF file, we're probably OK unless the
3035 	 symbol was defined in a non-ELF file.  Catch that case here.
3036 	 FIXME: We're still in trouble if the symbol was first seen in
3037 	 a dynamic object, and then later in a non-ELF regular object.  */
3038       if ((h->root.type == bfd_link_hash_defined
3039 	   || h->root.type == bfd_link_hash_defweak)
3040 	  && !h->def_regular
3041 	  && (h->root.u.def.section->owner != NULL
3042 	      ? (bfd_get_flavour (h->root.u.def.section->owner)
3043 		 != bfd_target_elf_flavour)
3044 	      : (bfd_is_abs_section (h->root.u.def.section)
3045 		 && !h->def_dynamic)))
3046 	h->def_regular = 1;
3047     }
3048 
3049   /* Backend specific symbol fixup.  */
3050   bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
3051   if (bed->elf_backend_fixup_symbol
3052       && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
3053     return false;
3054 
3055   /* If this is a final link, and the symbol was defined as a common
3056      symbol in a regular object file, and there was no definition in
3057      any dynamic object, then the linker will have allocated space for
3058      the symbol in a common section but the DEF_REGULAR
3059      flag will not have been set.  */
3060   if (h->root.type == bfd_link_hash_defined
3061       && !h->def_regular
3062       && h->ref_regular
3063       && !h->def_dynamic
3064       && (h->root.u.def.section->owner->flags & (DYNAMIC | BFD_PLUGIN)) == 0)
3065     h->def_regular = 1;
3066 
3067   /* Symbols defined in discarded sections shouldn't be dynamic.  */
3068   if (h->root.type == bfd_link_hash_undefined && h->indx == -3)
3069     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
3070 
3071   /* If a weak undefined symbol has non-default visibility, we also
3072      hide it from the dynamic linker.  */
3073   else if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
3074 	   && h->root.type == bfd_link_hash_undefweak)
3075     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
3076 
3077   /* A hidden versioned symbol in executable should be forced local if
3078      it is is locally defined, not referenced by shared library and not
3079      exported.  */
3080   else if (bfd_link_executable (eif->info)
3081 	   && h->versioned == versioned_hidden
3082 	   && !eif->info->export_dynamic
3083 	   && !h->dynamic
3084 	   && !h->ref_dynamic
3085 	   && h->def_regular)
3086     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
3087 
3088   /* If -Bsymbolic was used (which means to bind references to global
3089      symbols to the definition within the shared object), and this
3090      symbol was defined in a regular object, then it actually doesn't
3091      need a PLT entry.  Likewise, if the symbol has non-default
3092      visibility.  If the symbol has hidden or internal visibility, we
3093      will force it local.  */
3094   else if (h->needs_plt
3095 	   && bfd_link_pic (eif->info)
3096 	   && is_elf_hash_table (eif->info->hash)
3097 	   && (SYMBOLIC_BIND (eif->info, h)
3098 	       || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
3099 	   && h->def_regular)
3100     {
3101       bool force_local;
3102 
3103       force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3104 		     || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
3105       (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
3106     }
3107 
3108   /* If this is a weak defined symbol in a dynamic object, and we know
3109      the real definition in the dynamic object, copy interesting flags
3110      over to the real definition.  */
3111   if (h->is_weakalias)
3112     {
3113       struct elf_link_hash_entry *def = weakdef (h);
3114       while (def->root.type == bfd_link_hash_indirect)
3115         def = (struct elf_link_hash_entry *) def->root.u.i.link;
3116 
3117       /* If the real definition is defined by a regular object file,
3118 	 don't do anything special.  See the longer description in
3119 	 _bfd_elf_adjust_dynamic_symbol, below.  If the def is not
3120 	 bfd_link_hash_defined as it was when put on the alias list
3121 	 then it must have originally been a versioned symbol (for
3122 	 which a non-versioned indirect symbol is created) and later
3123 	 a definition for the non-versioned symbol is found.  In that
3124 	 case the indirection is flipped with the versioned symbol
3125 	 becoming an indirect pointing at the non-versioned symbol.
3126 	 Thus, not an alias any more.  */
3127       if (def->def_regular
3128 	  || def->root.type != bfd_link_hash_defined)
3129 	{
3130 	  h = def;
3131 	  while ((h = h->u.alias) != def)
3132 	    h->is_weakalias = 0;
3133 	}
3134       else
3135 	{
3136 	  while (h->root.type == bfd_link_hash_indirect)
3137 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
3138 	  BFD_ASSERT (h->root.type == bfd_link_hash_defined
3139 		      || h->root.type == bfd_link_hash_defweak);
3140 	  BFD_ASSERT (def->def_dynamic);
3141 	  (*bed->elf_backend_copy_indirect_symbol) (eif->info, def, h);
3142 	}
3143     }
3144 
3145   return true;
3146 }
3147 
3148 /* Make the backend pick a good value for a dynamic symbol.  This is
3149    called via elf_link_hash_traverse, and also calls itself
3150    recursively.  */
3151 
3152 static bool
_bfd_elf_adjust_dynamic_symbol(struct elf_link_hash_entry * h,void * data)3153 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
3154 {
3155   struct elf_info_failed *eif = (struct elf_info_failed *) data;
3156   struct elf_link_hash_table *htab;
3157   const struct elf_backend_data *bed;
3158 
3159   if (! is_elf_hash_table (eif->info->hash))
3160     return false;
3161 
3162   /* Ignore indirect symbols.  These are added by the versioning code.  */
3163   if (h->root.type == bfd_link_hash_indirect)
3164     return true;
3165 
3166   /* Fix the symbol flags.  */
3167   if (! _bfd_elf_fix_symbol_flags (h, eif))
3168     return false;
3169 
3170   htab = elf_hash_table (eif->info);
3171   bed = get_elf_backend_data (htab->dynobj);
3172 
3173   if (h->root.type == bfd_link_hash_undefweak)
3174     {
3175       if (eif->info->dynamic_undefined_weak == 0)
3176 	(*bed->elf_backend_hide_symbol) (eif->info, h, true);
3177       else if (eif->info->dynamic_undefined_weak > 0
3178 	       && h->ref_regular
3179 	       && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
3180 	       && !bfd_hide_sym_by_version (eif->info->version_info,
3181 					    h->root.root.string))
3182 	{
3183 	  if (!bfd_elf_link_record_dynamic_symbol (eif->info, h))
3184 	    {
3185 	      eif->failed = true;
3186 	      return false;
3187 	    }
3188 	}
3189     }
3190 
3191   /* If this symbol does not require a PLT entry, and it is not
3192      defined by a dynamic object, or is not referenced by a regular
3193      object, ignore it.  We do have to handle a weak defined symbol,
3194      even if no regular object refers to it, if we decided to add it
3195      to the dynamic symbol table.  FIXME: Do we normally need to worry
3196      about symbols which are defined by one dynamic object and
3197      referenced by another one?  */
3198   if (!h->needs_plt
3199       && h->type != STT_GNU_IFUNC
3200       && (h->def_regular
3201 	  || !h->def_dynamic
3202 	  || (!h->ref_regular
3203 	      && (!h->is_weakalias || weakdef (h)->dynindx == -1))))
3204     {
3205       h->plt = elf_hash_table (eif->info)->init_plt_offset;
3206       return true;
3207     }
3208 
3209   /* If we've already adjusted this symbol, don't do it again.  This
3210      can happen via a recursive call.  */
3211   if (h->dynamic_adjusted)
3212     return true;
3213 
3214   /* Don't look at this symbol again.  Note that we must set this
3215      after checking the above conditions, because we may look at a
3216      symbol once, decide not to do anything, and then get called
3217      recursively later after REF_REGULAR is set below.  */
3218   h->dynamic_adjusted = 1;
3219 
3220   /* If this is a weak definition, and we know a real definition, and
3221      the real symbol is not itself defined by a regular object file,
3222      then get a good value for the real definition.  We handle the
3223      real symbol first, for the convenience of the backend routine.
3224 
3225      Note that there is a confusing case here.  If the real definition
3226      is defined by a regular object file, we don't get the real symbol
3227      from the dynamic object, but we do get the weak symbol.  If the
3228      processor backend uses a COPY reloc, then if some routine in the
3229      dynamic object changes the real symbol, we will not see that
3230      change in the corresponding weak symbol.  This is the way other
3231      ELF linkers work as well, and seems to be a result of the shared
3232      library model.
3233 
3234      I will clarify this issue.  Most SVR4 shared libraries define the
3235      variable _timezone and define timezone as a weak synonym.  The
3236      tzset call changes _timezone.  If you write
3237        extern int timezone;
3238        int _timezone = 5;
3239        int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3240      you might expect that, since timezone is a synonym for _timezone,
3241      the same number will print both times.  However, if the processor
3242      backend uses a COPY reloc, then actually timezone will be copied
3243      into your process image, and, since you define _timezone
3244      yourself, _timezone will not.  Thus timezone and _timezone will
3245      wind up at different memory locations.  The tzset call will set
3246      _timezone, leaving timezone unchanged.  */
3247 
3248   if (h->is_weakalias)
3249     {
3250       struct elf_link_hash_entry *def = weakdef (h);
3251 
3252       /* If we get to this point, there is an implicit reference to
3253 	 the alias by a regular object file via the weak symbol H.  */
3254       def->ref_regular = 1;
3255 
3256       /* Ensure that the backend adjust_dynamic_symbol function sees
3257 	 the strong alias before H by recursively calling ourselves.  */
3258       if (!_bfd_elf_adjust_dynamic_symbol (def, eif))
3259 	return false;
3260     }
3261 
3262   /* If a symbol has no type and no size and does not require a PLT
3263      entry, then we are probably about to do the wrong thing here: we
3264      are probably going to create a COPY reloc for an empty object.
3265      This case can arise when a shared object is built with assembly
3266      code, and the assembly code fails to set the symbol type.  */
3267   if (h->size == 0
3268       && h->type == STT_NOTYPE
3269       && !h->needs_plt)
3270     _bfd_error_handler
3271       (_("warning: type and size of dynamic symbol `%s' are not defined"),
3272        h->root.root.string);
3273 
3274   if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3275     {
3276       eif->failed = true;
3277       return false;
3278     }
3279 
3280   return true;
3281 }
3282 
3283 /* Adjust the dynamic symbol, H, for copy in the dynamic bss section,
3284    DYNBSS.  */
3285 
3286 bool
_bfd_elf_adjust_dynamic_copy(struct bfd_link_info * info,struct elf_link_hash_entry * h,asection * dynbss)3287 _bfd_elf_adjust_dynamic_copy (struct bfd_link_info *info,
3288 			      struct elf_link_hash_entry *h,
3289 			      asection *dynbss)
3290 {
3291   unsigned int power_of_two;
3292   bfd_vma mask;
3293   asection *sec = h->root.u.def.section;
3294 
3295   /* The section alignment of the definition is the maximum alignment
3296      requirement of symbols defined in the section.  Since we don't
3297      know the symbol alignment requirement, we start with the
3298      maximum alignment and check low bits of the symbol address
3299      for the minimum alignment.  */
3300   power_of_two = bfd_section_alignment (sec);
3301   mask = ((bfd_vma) 1 << power_of_two) - 1;
3302   while ((h->root.u.def.value & mask) != 0)
3303     {
3304        mask >>= 1;
3305        --power_of_two;
3306     }
3307 
3308   if (power_of_two > bfd_section_alignment (dynbss))
3309     {
3310       /* Adjust the section alignment if needed.  */
3311       if (!bfd_set_section_alignment (dynbss, power_of_two))
3312 	return false;
3313     }
3314 
3315   /* We make sure that the symbol will be aligned properly.  */
3316   dynbss->size = BFD_ALIGN (dynbss->size, mask + 1);
3317 
3318   /* Define the symbol as being at this point in DYNBSS.  */
3319   h->root.u.def.section = dynbss;
3320   h->root.u.def.value = dynbss->size;
3321 
3322   /* Increment the size of DYNBSS to make room for the symbol.  */
3323   dynbss->size += h->size;
3324 
3325   /* No error if extern_protected_data is true.  */
3326   if (h->protected_def
3327       && (!info->extern_protected_data
3328 	  || (info->extern_protected_data < 0
3329 	      && !get_elf_backend_data (dynbss->owner)->extern_protected_data)))
3330     info->callbacks->einfo
3331       (_("%P: copy reloc against protected `%pT' is dangerous\n"),
3332        h->root.root.string);
3333 
3334   return true;
3335 }
3336 
3337 /* Adjust all external symbols pointing into SEC_MERGE sections
3338    to reflect the object merging within the sections.  */
3339 
3340 static bool
_bfd_elf_link_sec_merge_syms(struct elf_link_hash_entry * h,void * data)3341 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
3342 {
3343   asection *sec;
3344 
3345   if ((h->root.type == bfd_link_hash_defined
3346        || h->root.type == bfd_link_hash_defweak)
3347       && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
3348       && sec->sec_info_type == SEC_INFO_TYPE_MERGE)
3349     {
3350       bfd *output_bfd = (bfd *) data;
3351 
3352       h->root.u.def.value =
3353 	_bfd_merged_section_offset (output_bfd,
3354 				    &h->root.u.def.section,
3355 				    elf_section_data (sec)->sec_info,
3356 				    h->root.u.def.value);
3357     }
3358 
3359   return true;
3360 }
3361 
3362 /* Returns false if the symbol referred to by H should be considered
3363    to resolve local to the current module, and true if it should be
3364    considered to bind dynamically.  */
3365 
3366 bool
_bfd_elf_dynamic_symbol_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bool not_local_protected)3367 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
3368 			   struct bfd_link_info *info,
3369 			   bool not_local_protected)
3370 {
3371   bool binding_stays_local_p;
3372   const struct elf_backend_data *bed;
3373   struct elf_link_hash_table *hash_table;
3374 
3375   if (h == NULL)
3376     return false;
3377 
3378   while (h->root.type == bfd_link_hash_indirect
3379 	 || h->root.type == bfd_link_hash_warning)
3380     h = (struct elf_link_hash_entry *) h->root.u.i.link;
3381 
3382   /* If it was forced local, then clearly it's not dynamic.  */
3383   if (h->dynindx == -1)
3384     return false;
3385   if (h->forced_local)
3386     return false;
3387 
3388   /* Identify the cases where name binding rules say that a
3389      visible symbol resolves locally.  */
3390   binding_stays_local_p = (bfd_link_executable (info)
3391 			   || SYMBOLIC_BIND (info, h));
3392 
3393   switch (ELF_ST_VISIBILITY (h->other))
3394     {
3395     case STV_INTERNAL:
3396     case STV_HIDDEN:
3397       return false;
3398 
3399     case STV_PROTECTED:
3400       hash_table = elf_hash_table (info);
3401       if (!is_elf_hash_table (&hash_table->root))
3402 	return false;
3403 
3404       bed = get_elf_backend_data (hash_table->dynobj);
3405 
3406       /* Proper resolution for function pointer equality may require
3407 	 that these symbols perhaps be resolved dynamically, even though
3408 	 we should be resolving them to the current module.  */
3409       if (!not_local_protected || !bed->is_function_type (h->type))
3410 	binding_stays_local_p = true;
3411       break;
3412 
3413     default:
3414       break;
3415     }
3416 
3417   /* If it isn't defined locally, then clearly it's dynamic.  */
3418   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
3419     return true;
3420 
3421   /* Otherwise, the symbol is dynamic if binding rules don't tell
3422      us that it remains local.  */
3423   return !binding_stays_local_p;
3424 }
3425 
3426 /* Return true if the symbol referred to by H should be considered
3427    to resolve local to the current module, and false otherwise.  Differs
3428    from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
3429    undefined symbols.  The two functions are virtually identical except
3430    for the place where dynindx == -1 is tested.  If that test is true,
3431    _bfd_elf_dynamic_symbol_p will say the symbol is local, while
3432    _bfd_elf_symbol_refs_local_p will say the symbol is local only for
3433    defined symbols.
3434    It might seem that _bfd_elf_dynamic_symbol_p could be rewritten as
3435    !_bfd_elf_symbol_refs_local_p, except that targets differ in their
3436    treatment of undefined weak symbols.  For those that do not make
3437    undefined weak symbols dynamic, both functions may return false.  */
3438 
3439 bool
_bfd_elf_symbol_refs_local_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bool local_protected)3440 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
3441 			      struct bfd_link_info *info,
3442 			      bool local_protected)
3443 {
3444   const struct elf_backend_data *bed;
3445   struct elf_link_hash_table *hash_table;
3446 
3447   /* If it's a local sym, of course we resolve locally.  */
3448   if (h == NULL)
3449     return true;
3450 
3451   /* STV_HIDDEN or STV_INTERNAL ones must be local.  */
3452   if (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
3453       || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL)
3454     return true;
3455 
3456   /* Forced local symbols resolve locally.  */
3457   if (h->forced_local)
3458     return true;
3459 
3460   /* Common symbols that become definitions don't get the DEF_REGULAR
3461      flag set, so test it first, and don't bail out.  */
3462   if (ELF_COMMON_DEF_P (h))
3463     /* Do nothing.  */;
3464   /* If we don't have a definition in a regular file, then we can't
3465      resolve locally.  The sym is either undefined or dynamic.  */
3466   else if (!h->def_regular)
3467     return false;
3468 
3469   /* Non-dynamic symbols resolve locally.  */
3470   if (h->dynindx == -1)
3471     return true;
3472 
3473   /* At this point, we know the symbol is defined and dynamic.  In an
3474      executable it must resolve locally, likewise when building symbolic
3475      shared libraries.  */
3476   if (bfd_link_executable (info) || SYMBOLIC_BIND (info, h))
3477     return true;
3478 
3479   /* Now deal with defined dynamic symbols in shared libraries.  Ones
3480      with default visibility might not resolve locally.  */
3481   if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
3482     return false;
3483 
3484   hash_table = elf_hash_table (info);
3485   if (!is_elf_hash_table (&hash_table->root))
3486     return true;
3487 
3488   /* STV_PROTECTED symbols with indirect external access are local. */
3489   if (info->indirect_extern_access > 0)
3490     return true;
3491 
3492   bed = get_elf_backend_data (hash_table->dynobj);
3493 
3494   /* If extern_protected_data is false, STV_PROTECTED non-function
3495      symbols are local.  */
3496   if ((!info->extern_protected_data
3497        || (info->extern_protected_data < 0
3498 	   && !bed->extern_protected_data))
3499       && !bed->is_function_type (h->type))
3500     return true;
3501 
3502   /* Function pointer equality tests may require that STV_PROTECTED
3503      symbols be treated as dynamic symbols.  If the address of a
3504      function not defined in an executable is set to that function's
3505      plt entry in the executable, then the address of the function in
3506      a shared library must also be the plt entry in the executable.  */
3507   return local_protected;
3508 }
3509 
3510 /* Caches some TLS segment info, and ensures that the TLS segment vma is
3511    aligned.  Returns the first TLS output section.  */
3512 
3513 struct bfd_section *
_bfd_elf_tls_setup(bfd * obfd,struct bfd_link_info * info)3514 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
3515 {
3516   struct bfd_section *sec, *tls;
3517   unsigned int align = 0;
3518 
3519   for (sec = obfd->sections; sec != NULL; sec = sec->next)
3520     if ((sec->flags & SEC_THREAD_LOCAL) != 0)
3521       break;
3522   tls = sec;
3523 
3524   for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
3525     if (sec->alignment_power > align)
3526       align = sec->alignment_power;
3527 
3528   elf_hash_table (info)->tls_sec = tls;
3529 
3530   /* Ensure the alignment of the first section (usually .tdata) is the largest
3531      alignment, so that the tls segment starts aligned.  */
3532   if (tls != NULL)
3533     tls->alignment_power = align;
3534 
3535   return tls;
3536 }
3537 
3538 /* Return TRUE iff this is a non-common, definition of a non-function symbol.  */
3539 static bool
is_global_data_symbol_definition(bfd * abfd ATTRIBUTE_UNUSED,Elf_Internal_Sym * sym)3540 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
3541 				  Elf_Internal_Sym *sym)
3542 {
3543   const struct elf_backend_data *bed;
3544 
3545   /* Local symbols do not count, but target specific ones might.  */
3546   if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
3547       && ELF_ST_BIND (sym->st_info) < STB_LOOS)
3548     return false;
3549 
3550   bed = get_elf_backend_data (abfd);
3551   /* Function symbols do not count.  */
3552   if (bed->is_function_type (ELF_ST_TYPE (sym->st_info)))
3553     return false;
3554 
3555   /* If the section is undefined, then so is the symbol.  */
3556   if (sym->st_shndx == SHN_UNDEF)
3557     return false;
3558 
3559   /* If the symbol is defined in the common section, then
3560      it is a common definition and so does not count.  */
3561   if (bed->common_definition (sym))
3562     return false;
3563 
3564   /* If the symbol is in a target specific section then we
3565      must rely upon the backend to tell us what it is.  */
3566   if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
3567     /* FIXME - this function is not coded yet:
3568 
3569        return _bfd_is_global_symbol_definition (abfd, sym);
3570 
3571        Instead for now assume that the definition is not global,
3572        Even if this is wrong, at least the linker will behave
3573        in the same way that it used to do.  */
3574     return false;
3575 
3576   return true;
3577 }
3578 
3579 /* Search the symbol table of the archive element of the archive ABFD
3580    whose archive map contains a mention of SYMDEF, and determine if
3581    the symbol is defined in this element.  */
3582 static bool
elf_link_is_defined_archive_symbol(bfd * abfd,carsym * symdef)3583 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
3584 {
3585   Elf_Internal_Shdr * hdr;
3586   size_t symcount;
3587   size_t extsymcount;
3588   size_t extsymoff;
3589   Elf_Internal_Sym *isymbuf;
3590   Elf_Internal_Sym *isym;
3591   Elf_Internal_Sym *isymend;
3592   bool result;
3593 
3594   abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset, NULL);
3595   if (abfd == NULL)
3596     return false;
3597 
3598   if (! bfd_check_format (abfd, bfd_object))
3599     return false;
3600 
3601   /* Select the appropriate symbol table.  If we don't know if the
3602      object file is an IR object, give linker LTO plugin a chance to
3603      get the correct symbol table.  */
3604   if (abfd->plugin_format == bfd_plugin_yes
3605 #if BFD_SUPPORTS_PLUGINS
3606       || (abfd->plugin_format == bfd_plugin_unknown
3607 	  && bfd_link_plugin_object_p (abfd))
3608 #endif
3609       )
3610     {
3611       /* Use the IR symbol table if the object has been claimed by
3612 	 plugin.  */
3613       abfd = abfd->plugin_dummy_bfd;
3614       hdr = &elf_tdata (abfd)->symtab_hdr;
3615     }
3616   else
3617     {
3618       if (elf_use_dt_symtab_p (abfd))
3619 	{
3620 	  bfd_set_error (bfd_error_wrong_format);
3621 	  return false;
3622 	}
3623 
3624       if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
3625 	hdr = &elf_tdata (abfd)->symtab_hdr;
3626       else
3627 	hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3628     }
3629 
3630   symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
3631 
3632   /* The sh_info field of the symtab header tells us where the
3633      external symbols start.  We don't care about the local symbols.  */
3634   if (elf_bad_symtab (abfd))
3635     {
3636       extsymcount = symcount;
3637       extsymoff = 0;
3638     }
3639   else
3640     {
3641       extsymcount = symcount - hdr->sh_info;
3642       extsymoff = hdr->sh_info;
3643     }
3644 
3645   if (extsymcount == 0)
3646     return false;
3647 
3648   /* Read in the symbol table.  */
3649   isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3650 				  NULL, NULL, NULL);
3651   if (isymbuf == NULL)
3652     return false;
3653 
3654   /* Scan the symbol table looking for SYMDEF.  */
3655   result = false;
3656   for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
3657     {
3658       const char *name;
3659 
3660       name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3661 					      isym->st_name);
3662       if (name == NULL)
3663 	break;
3664 
3665       if (strcmp (name, symdef->name) == 0)
3666 	{
3667 	  result = is_global_data_symbol_definition (abfd, isym);
3668 	  break;
3669 	}
3670     }
3671 
3672   free (isymbuf);
3673 
3674   return result;
3675 }
3676 
3677 /* Add an entry to the .dynamic table.  */
3678 
3679 bool
_bfd_elf_add_dynamic_entry(struct bfd_link_info * info,bfd_vma tag,bfd_vma val)3680 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
3681 			    bfd_vma tag,
3682 			    bfd_vma val)
3683 {
3684   struct elf_link_hash_table *hash_table;
3685   const struct elf_backend_data *bed;
3686   asection *s;
3687   bfd_size_type newsize;
3688   bfd_byte *newcontents;
3689   Elf_Internal_Dyn dyn;
3690 
3691   hash_table = elf_hash_table (info);
3692   if (! is_elf_hash_table (&hash_table->root))
3693     return false;
3694 
3695   if (tag == DT_RELA || tag == DT_REL)
3696     hash_table->dynamic_relocs = true;
3697 
3698   bed = get_elf_backend_data (hash_table->dynobj);
3699   s = bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3700   BFD_ASSERT (s != NULL);
3701 
3702   newsize = s->size + bed->s->sizeof_dyn;
3703   newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
3704   if (newcontents == NULL)
3705     return false;
3706 
3707   dyn.d_tag = tag;
3708   dyn.d_un.d_val = val;
3709   bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
3710 
3711   s->size = newsize;
3712   s->contents = newcontents;
3713 
3714   return true;
3715 }
3716 
3717 /* Strip zero-sized dynamic sections.  */
3718 
3719 bool
_bfd_elf_strip_zero_sized_dynamic_sections(struct bfd_link_info * info)3720 _bfd_elf_strip_zero_sized_dynamic_sections (struct bfd_link_info *info)
3721 {
3722   struct elf_link_hash_table *hash_table;
3723   const struct elf_backend_data *bed;
3724   asection *s, *sdynamic, **pp;
3725   asection *rela_dyn, *rel_dyn;
3726   Elf_Internal_Dyn dyn;
3727   bfd_byte *extdyn, *next;
3728   void (*swap_dyn_in) (bfd *, const void *, Elf_Internal_Dyn *);
3729   bool strip_zero_sized;
3730   bool strip_zero_sized_plt;
3731 
3732   if (bfd_link_relocatable (info))
3733     return true;
3734 
3735   hash_table = elf_hash_table (info);
3736   if (!is_elf_hash_table (&hash_table->root))
3737     return false;
3738 
3739   if (!hash_table->dynobj)
3740     return true;
3741 
3742   sdynamic= bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3743   if (!sdynamic)
3744     return true;
3745 
3746   bed = get_elf_backend_data (hash_table->dynobj);
3747   swap_dyn_in = bed->s->swap_dyn_in;
3748 
3749   strip_zero_sized = false;
3750   strip_zero_sized_plt = false;
3751 
3752   /* Strip zero-sized dynamic sections.  */
3753   rela_dyn = bfd_get_section_by_name (info->output_bfd, ".rela.dyn");
3754   rel_dyn = bfd_get_section_by_name (info->output_bfd, ".rel.dyn");
3755   for (pp = &info->output_bfd->sections; (s = *pp) != NULL;)
3756     if (s->size == 0
3757 	&& (s == rela_dyn
3758 	    || s == rel_dyn
3759 	    || s == hash_table->srelplt->output_section
3760 	    || s == hash_table->splt->output_section))
3761       {
3762 	*pp = s->next;
3763 	info->output_bfd->section_count--;
3764 	strip_zero_sized = true;
3765 	if (s == rela_dyn)
3766 	  s = rela_dyn;
3767 	if (s == rel_dyn)
3768 	  s = rel_dyn;
3769 	else if (s == hash_table->splt->output_section)
3770 	  {
3771 	    s = hash_table->splt;
3772 	    strip_zero_sized_plt = true;
3773 	  }
3774 	else
3775 	  s = hash_table->srelplt;
3776 	s->flags |= SEC_EXCLUDE;
3777 	s->output_section = bfd_abs_section_ptr;
3778       }
3779     else
3780       pp = &s->next;
3781 
3782   if (strip_zero_sized_plt && sdynamic->size != 0)
3783     for (extdyn = sdynamic->contents;
3784 	 extdyn < sdynamic->contents + sdynamic->size;
3785 	 extdyn = next)
3786       {
3787 	next = extdyn + bed->s->sizeof_dyn;
3788 	swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3789 	switch (dyn.d_tag)
3790 	  {
3791 	  default:
3792 	    break;
3793 	  case DT_JMPREL:
3794 	  case DT_PLTRELSZ:
3795 	  case DT_PLTREL:
3796 	    /* Strip DT_PLTRELSZ, DT_JMPREL and DT_PLTREL entries if
3797 	       the procedure linkage table (the .plt section) has been
3798 	       removed.  */
3799 	    memmove (extdyn, next,
3800 		     sdynamic->size - (next - sdynamic->contents));
3801 	    next = extdyn;
3802 	  }
3803       }
3804 
3805   if (strip_zero_sized)
3806     {
3807       /* Regenerate program headers.  */
3808       elf_seg_map (info->output_bfd) = NULL;
3809       return _bfd_elf_map_sections_to_segments (info->output_bfd, info,
3810 						NULL);
3811     }
3812 
3813   return true;
3814 }
3815 
3816 /* Add a DT_NEEDED entry for this dynamic object.  Returns -1 on error,
3817    1 if a DT_NEEDED tag already exists, and 0 on success.  */
3818 
3819 int
bfd_elf_add_dt_needed_tag(bfd * abfd,struct bfd_link_info * info)3820 bfd_elf_add_dt_needed_tag (bfd *abfd, struct bfd_link_info *info)
3821 {
3822   struct elf_link_hash_table *hash_table;
3823   size_t strindex;
3824   const char *soname;
3825 
3826   if (!_bfd_elf_link_create_dynstrtab (abfd, info))
3827     return -1;
3828 
3829   hash_table = elf_hash_table (info);
3830   soname = elf_dt_name (abfd);
3831   strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, false);
3832   if (strindex == (size_t) -1)
3833     return -1;
3834 
3835   if (_bfd_elf_strtab_refcount (hash_table->dynstr, strindex) != 1)
3836     {
3837       asection *sdyn;
3838       const struct elf_backend_data *bed;
3839       bfd_byte *extdyn;
3840 
3841       bed = get_elf_backend_data (hash_table->dynobj);
3842       sdyn = bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3843       if (sdyn != NULL && sdyn->size != 0)
3844 	for (extdyn = sdyn->contents;
3845 	     extdyn < sdyn->contents + sdyn->size;
3846 	     extdyn += bed->s->sizeof_dyn)
3847 	  {
3848 	    Elf_Internal_Dyn dyn;
3849 
3850 	    bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3851 	    if (dyn.d_tag == DT_NEEDED
3852 		&& dyn.d_un.d_val == strindex)
3853 	      {
3854 		_bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3855 		return 1;
3856 	      }
3857 	  }
3858     }
3859 
3860   if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
3861     return -1;
3862 
3863   if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
3864     return -1;
3865 
3866   return 0;
3867 }
3868 
3869 /* Return true if SONAME is on the needed list between NEEDED and STOP
3870    (or the end of list if STOP is NULL), and needed by a library that
3871    will be loaded.  */
3872 
3873 static bool
on_needed_list(const char * soname,struct bfd_link_needed_list * needed,struct bfd_link_needed_list * stop)3874 on_needed_list (const char *soname,
3875 		struct bfd_link_needed_list *needed,
3876 		struct bfd_link_needed_list *stop)
3877 {
3878   struct bfd_link_needed_list *look;
3879   for (look = needed; look != stop; look = look->next)
3880     if (strcmp (soname, look->name) == 0
3881 	&& ((elf_dyn_lib_class (look->by) & DYN_AS_NEEDED) == 0
3882 	    /* If needed by a library that itself is not directly
3883 	       needed, recursively check whether that library is
3884 	       indirectly needed.  Since we add DT_NEEDED entries to
3885 	       the end of the list, library dependencies appear after
3886 	       the library.  Therefore search prior to the current
3887 	       LOOK, preventing possible infinite recursion.  */
3888 	    || on_needed_list (elf_dt_name (look->by), needed, look)))
3889       return true;
3890 
3891   return false;
3892 }
3893 
3894 /* Sort symbol by value, section, size, and type.  */
3895 static int
elf_sort_symbol(const void * arg1,const void * arg2)3896 elf_sort_symbol (const void *arg1, const void *arg2)
3897 {
3898   const struct elf_link_hash_entry *h1;
3899   const struct elf_link_hash_entry *h2;
3900   bfd_signed_vma vdiff;
3901   int sdiff;
3902   const char *n1;
3903   const char *n2;
3904 
3905   h1 = *(const struct elf_link_hash_entry **) arg1;
3906   h2 = *(const struct elf_link_hash_entry **) arg2;
3907   vdiff = h1->root.u.def.value - h2->root.u.def.value;
3908   if (vdiff != 0)
3909     return vdiff > 0 ? 1 : -1;
3910 
3911   sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
3912   if (sdiff != 0)
3913     return sdiff;
3914 
3915   /* Sort so that sized symbols are selected over zero size symbols.  */
3916   vdiff = h1->size - h2->size;
3917   if (vdiff != 0)
3918     return vdiff > 0 ? 1 : -1;
3919 
3920   /* Sort so that STT_OBJECT is selected over STT_NOTYPE.  */
3921   if (h1->type != h2->type)
3922     return h1->type - h2->type;
3923 
3924   /* If symbols are properly sized and typed, and multiple strong
3925      aliases are not defined in a shared library by the user we
3926      shouldn't get here.  Unfortunately linker script symbols like
3927      __bss_start sometimes match a user symbol defined at the start of
3928      .bss without proper size and type.  We'd like to preference the
3929      user symbol over reserved system symbols.  Sort on leading
3930      underscores.  */
3931   n1 = h1->root.root.string;
3932   n2 = h2->root.root.string;
3933   while (*n1 == *n2)
3934     {
3935       if (*n1 == 0)
3936 	break;
3937       ++n1;
3938       ++n2;
3939     }
3940   if (*n1 == '_')
3941     return -1;
3942   if (*n2 == '_')
3943     return 1;
3944 
3945   /* Final sort on name selects user symbols like '_u' over reserved
3946      system symbols like '_Z' and also will avoid qsort instability.  */
3947   return *n1 - *n2;
3948 }
3949 
3950 /* This function is used to adjust offsets into .dynstr for
3951    dynamic symbols.  This is called via elf_link_hash_traverse.  */
3952 
3953 static bool
elf_adjust_dynstr_offsets(struct elf_link_hash_entry * h,void * data)3954 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3955 {
3956   struct elf_strtab_hash *dynstr = (struct elf_strtab_hash *) data;
3957 
3958   if (h->dynindx != -1)
3959     h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3960   return true;
3961 }
3962 
3963 /* Assign string offsets in .dynstr, update all structures referencing
3964    them.  */
3965 
3966 static bool
elf_finalize_dynstr(bfd * output_bfd,struct bfd_link_info * info)3967 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3968 {
3969   struct elf_link_hash_table *hash_table = elf_hash_table (info);
3970   struct elf_link_local_dynamic_entry *entry;
3971   struct elf_strtab_hash *dynstr = hash_table->dynstr;
3972   bfd *dynobj = hash_table->dynobj;
3973   asection *sdyn;
3974   bfd_size_type size;
3975   const struct elf_backend_data *bed;
3976   bfd_byte *extdyn;
3977 
3978   _bfd_elf_strtab_finalize (dynstr);
3979   size = _bfd_elf_strtab_size (dynstr);
3980 
3981   /* Allow the linker to examine the dynsymtab now it's fully populated.  */
3982 
3983   if (info->callbacks->examine_strtab)
3984     info->callbacks->examine_strtab (dynstr);
3985 
3986   bed = get_elf_backend_data (dynobj);
3987   sdyn = bfd_get_linker_section (dynobj, ".dynamic");
3988   BFD_ASSERT (sdyn != NULL);
3989 
3990   /* Update all .dynamic entries referencing .dynstr strings.  */
3991   for (extdyn = sdyn->contents;
3992        extdyn < PTR_ADD (sdyn->contents, sdyn->size);
3993        extdyn += bed->s->sizeof_dyn)
3994     {
3995       Elf_Internal_Dyn dyn;
3996 
3997       bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3998       switch (dyn.d_tag)
3999 	{
4000 	case DT_STRSZ:
4001 	  dyn.d_un.d_val = size;
4002 	  break;
4003 	case DT_NEEDED:
4004 	case DT_SONAME:
4005 	case DT_RPATH:
4006 	case DT_RUNPATH:
4007 	case DT_FILTER:
4008 	case DT_AUXILIARY:
4009 	case DT_AUDIT:
4010 	case DT_DEPAUDIT:
4011 	  dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
4012 	  break;
4013 	default:
4014 	  continue;
4015 	}
4016       bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
4017     }
4018 
4019   /* Now update local dynamic symbols.  */
4020   for (entry = hash_table->dynlocal; entry ; entry = entry->next)
4021     entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
4022 						  entry->isym.st_name);
4023 
4024   /* And the rest of dynamic symbols.  */
4025   elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
4026 
4027   /* Adjust version definitions.  */
4028   if (elf_tdata (output_bfd)->cverdefs)
4029     {
4030       asection *s;
4031       bfd_byte *p;
4032       size_t i;
4033       Elf_Internal_Verdef def;
4034       Elf_Internal_Verdaux defaux;
4035 
4036       s = bfd_get_linker_section (dynobj, ".gnu.version_d");
4037       p = s->contents;
4038       do
4039 	{
4040 	  _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
4041 				   &def);
4042 	  p += sizeof (Elf_External_Verdef);
4043 	  if (def.vd_aux != sizeof (Elf_External_Verdef))
4044 	    continue;
4045 	  for (i = 0; i < def.vd_cnt; ++i)
4046 	    {
4047 	      _bfd_elf_swap_verdaux_in (output_bfd,
4048 					(Elf_External_Verdaux *) p, &defaux);
4049 	      defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
4050 							defaux.vda_name);
4051 	      _bfd_elf_swap_verdaux_out (output_bfd,
4052 					 &defaux, (Elf_External_Verdaux *) p);
4053 	      p += sizeof (Elf_External_Verdaux);
4054 	    }
4055 	}
4056       while (def.vd_next);
4057     }
4058 
4059   /* Adjust version references.  */
4060   if (elf_tdata (output_bfd)->verref)
4061     {
4062       asection *s;
4063       bfd_byte *p;
4064       size_t i;
4065       Elf_Internal_Verneed need;
4066       Elf_Internal_Vernaux needaux;
4067 
4068       s = bfd_get_linker_section (dynobj, ".gnu.version_r");
4069       p = s->contents;
4070       do
4071 	{
4072 	  _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
4073 				    &need);
4074 	  need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
4075 	  _bfd_elf_swap_verneed_out (output_bfd, &need,
4076 				     (Elf_External_Verneed *) p);
4077 	  p += sizeof (Elf_External_Verneed);
4078 	  for (i = 0; i < need.vn_cnt; ++i)
4079 	    {
4080 	      _bfd_elf_swap_vernaux_in (output_bfd,
4081 					(Elf_External_Vernaux *) p, &needaux);
4082 	      needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
4083 							 needaux.vna_name);
4084 	      _bfd_elf_swap_vernaux_out (output_bfd,
4085 					 &needaux,
4086 					 (Elf_External_Vernaux *) p);
4087 	      p += sizeof (Elf_External_Vernaux);
4088 	    }
4089 	}
4090       while (need.vn_next);
4091     }
4092 
4093   return true;
4094 }
4095 
4096 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
4097    The default is to only match when the INPUT and OUTPUT are exactly
4098    the same target.  */
4099 
4100 bool
_bfd_elf_default_relocs_compatible(const bfd_target * input,const bfd_target * output)4101 _bfd_elf_default_relocs_compatible (const bfd_target *input,
4102 				    const bfd_target *output)
4103 {
4104   return input == output;
4105 }
4106 
4107 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
4108    This version is used when different targets for the same architecture
4109    are virtually identical.  */
4110 
4111 bool
_bfd_elf_relocs_compatible(const bfd_target * input,const bfd_target * output)4112 _bfd_elf_relocs_compatible (const bfd_target *input,
4113 			    const bfd_target *output)
4114 {
4115   const struct elf_backend_data *obed, *ibed;
4116 
4117   if (input == output)
4118     return true;
4119 
4120   ibed = xvec_get_elf_backend_data (input);
4121   obed = xvec_get_elf_backend_data (output);
4122 
4123   if (ibed->arch != obed->arch)
4124     return false;
4125 
4126   /* If both backends are using this function, deem them compatible.  */
4127   return ibed->relocs_compatible == obed->relocs_compatible;
4128 }
4129 
4130 /* Make a special call to the linker "notice" function to tell it that
4131    we are about to handle an as-needed lib, or have finished
4132    processing the lib.  */
4133 
4134 bool
_bfd_elf_notice_as_needed(bfd * ibfd,struct bfd_link_info * info,enum notice_asneeded_action act)4135 _bfd_elf_notice_as_needed (bfd *ibfd,
4136 			   struct bfd_link_info *info,
4137 			   enum notice_asneeded_action act)
4138 {
4139   return (*info->callbacks->notice) (info, NULL, NULL, ibfd, NULL, act, 0);
4140 }
4141 
4142 /* Call ACTION on each relocation in an ELF object file.  */
4143 
4144 bool
_bfd_elf_link_iterate_on_relocs(bfd * abfd,struct bfd_link_info * info,bool (* action)(bfd *,struct bfd_link_info *,asection *,const Elf_Internal_Rela *))4145 _bfd_elf_link_iterate_on_relocs
4146   (bfd *abfd, struct bfd_link_info *info,
4147    bool (*action) (bfd *, struct bfd_link_info *, asection *,
4148 		   const Elf_Internal_Rela *))
4149 {
4150   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
4151   struct elf_link_hash_table *htab = elf_hash_table (info);
4152 
4153   /* If this object is the same format as the output object, and it is
4154      not a shared library, then let the backend look through the
4155      relocs.
4156 
4157      This is required to build global offset table entries and to
4158      arrange for dynamic relocs.  It is not required for the
4159      particular common case of linking non PIC code, even when linking
4160      against shared libraries, but unfortunately there is no way of
4161      knowing whether an object file has been compiled PIC or not.
4162      Looking through the relocs is not particularly time consuming.
4163      The problem is that we must either (1) keep the relocs in memory,
4164      which causes the linker to require additional runtime memory or
4165      (2) read the relocs twice from the input file, which wastes time.
4166      This would be a good case for using mmap.
4167 
4168      I have no idea how to handle linking PIC code into a file of a
4169      different format.  It probably can't be done.  */
4170   if ((abfd->flags & DYNAMIC) == 0
4171       && is_elf_hash_table (&htab->root)
4172       && elf_object_id (abfd) == elf_hash_table_id (htab)
4173       && (*bed->relocs_compatible) (abfd->xvec, info->output_bfd->xvec))
4174     {
4175       asection *o;
4176 
4177       for (o = abfd->sections; o != NULL; o = o->next)
4178 	{
4179 	  Elf_Internal_Rela *internal_relocs;
4180 	  bool ok;
4181 
4182 	  /* Don't check relocations in excluded sections.  Don't do
4183 	     anything special with non-loaded, non-alloced sections.
4184 	     In particular, any relocs in such sections should not
4185 	     affect GOT and PLT reference counting (ie.  we don't
4186 	     allow them to create GOT or PLT entries), there's no
4187 	     possibility or desire to optimize TLS relocs, and
4188 	     there's not much point in propagating relocs to shared
4189 	     libs that the dynamic linker won't relocate.  */
4190 	  if ((o->flags & SEC_ALLOC) == 0
4191 	      || (o->flags & SEC_RELOC) == 0
4192 	      || (o->flags & SEC_EXCLUDE) != 0
4193 	      || o->reloc_count == 0
4194 	      || ((info->strip == strip_all || info->strip == strip_debugger)
4195 		  && (o->flags & SEC_DEBUGGING) != 0)
4196 	      || bfd_is_abs_section (o->output_section))
4197 	    continue;
4198 
4199 	  internal_relocs = _bfd_elf_link_info_read_relocs (abfd, info,
4200 							    o, NULL,
4201 							    NULL,
4202 							    _bfd_link_keep_memory (info));
4203 	  if (internal_relocs == NULL)
4204 	    return false;
4205 
4206 	  ok = action (abfd, info, o, internal_relocs);
4207 
4208 	  if (elf_section_data (o)->relocs != internal_relocs)
4209 	    free (internal_relocs);
4210 
4211 	  if (! ok)
4212 	    return false;
4213 	}
4214     }
4215 
4216   return true;
4217 }
4218 
4219 /* Check relocations in an ELF object file.  This is called after
4220    all input files have been opened.  */
4221 
4222 bool
_bfd_elf_link_check_relocs(bfd * abfd,struct bfd_link_info * info)4223 _bfd_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
4224 {
4225   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
4226   if (bed->check_relocs != NULL)
4227     return _bfd_elf_link_iterate_on_relocs (abfd, info,
4228 					    bed->check_relocs);
4229   return true;
4230 }
4231 
4232 /* Add symbols from an ELF object file to the linker hash table.  */
4233 
4234 static bool
elf_link_add_object_symbols(bfd * abfd,struct bfd_link_info * info)4235 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
4236 {
4237   Elf_Internal_Ehdr *ehdr;
4238   Elf_Internal_Shdr *hdr;
4239   size_t symcount;
4240   size_t extsymcount;
4241   size_t extsymoff;
4242   struct elf_link_hash_entry **sym_hash;
4243   bool dynamic;
4244   Elf_External_Versym *extversym = NULL;
4245   Elf_External_Versym *extversym_end = NULL;
4246   Elf_External_Versym *ever;
4247   struct elf_link_hash_entry *weaks;
4248   struct elf_link_hash_entry **nondeflt_vers = NULL;
4249   size_t nondeflt_vers_cnt = 0;
4250   Elf_Internal_Sym *isymbuf = NULL;
4251   Elf_Internal_Sym *isym;
4252   Elf_Internal_Sym *isymend;
4253   const struct elf_backend_data *bed;
4254   bool add_needed;
4255   struct elf_link_hash_table *htab;
4256   void *alloc_mark = NULL;
4257   struct bfd_hash_entry **old_table = NULL;
4258   unsigned int old_size = 0;
4259   unsigned int old_count = 0;
4260   void *old_tab = NULL;
4261   void *old_ent;
4262   struct bfd_link_hash_entry *old_undefs = NULL;
4263   struct bfd_link_hash_entry *old_undefs_tail = NULL;
4264   void *old_strtab = NULL;
4265   size_t tabsize = 0;
4266   asection *s;
4267   bool just_syms;
4268 
4269   htab = elf_hash_table (info);
4270   bed = get_elf_backend_data (abfd);
4271 
4272   if (elf_use_dt_symtab_p (abfd))
4273     {
4274       bfd_set_error (bfd_error_wrong_format);
4275       return false;
4276     }
4277 
4278   if ((abfd->flags & DYNAMIC) == 0)
4279     dynamic = false;
4280   else
4281     {
4282       dynamic = true;
4283 
4284       /* You can't use -r against a dynamic object.  Also, there's no
4285 	 hope of using a dynamic object which does not exactly match
4286 	 the format of the output file.  */
4287       if (bfd_link_relocatable (info)
4288 	  || !is_elf_hash_table (&htab->root)
4289 	  || info->output_bfd->xvec != abfd->xvec)
4290 	{
4291 	  if (bfd_link_relocatable (info))
4292 	    bfd_set_error (bfd_error_invalid_operation);
4293 	  else
4294 	    bfd_set_error (bfd_error_wrong_format);
4295 	  goto error_return;
4296 	}
4297     }
4298 
4299   ehdr = elf_elfheader (abfd);
4300   if (info->warn_alternate_em
4301       && bed->elf_machine_code != ehdr->e_machine
4302       && ((bed->elf_machine_alt1 != 0
4303 	   && ehdr->e_machine == bed->elf_machine_alt1)
4304 	  || (bed->elf_machine_alt2 != 0
4305 	      && ehdr->e_machine == bed->elf_machine_alt2)))
4306     _bfd_error_handler
4307       /* xgettext:c-format */
4308       (_("alternate ELF machine code found (%d) in %pB, expecting %d"),
4309        ehdr->e_machine, abfd, bed->elf_machine_code);
4310 
4311   /* As a GNU extension, any input sections which are named
4312      .gnu.warning.SYMBOL are treated as warning symbols for the given
4313      symbol.  This differs from .gnu.warning sections, which generate
4314      warnings when they are included in an output file.  */
4315   /* PR 12761: Also generate this warning when building shared libraries.  */
4316   for (s = abfd->sections; s != NULL; s = s->next)
4317     {
4318       const char *name;
4319 
4320       name = bfd_section_name (s);
4321       if (startswith (name, ".gnu.warning."))
4322 	{
4323 	  char *msg;
4324 	  bfd_size_type sz;
4325 
4326 	  name += sizeof ".gnu.warning." - 1;
4327 
4328 	  /* If this is a shared object, then look up the symbol
4329 	     in the hash table.  If it is there, and it is already
4330 	     been defined, then we will not be using the entry
4331 	     from this shared object, so we don't need to warn.
4332 	     FIXME: If we see the definition in a regular object
4333 	     later on, we will warn, but we shouldn't.  The only
4334 	     fix is to keep track of what warnings we are supposed
4335 	     to emit, and then handle them all at the end of the
4336 	     link.  */
4337 	  if (dynamic)
4338 	    {
4339 	      struct elf_link_hash_entry *h;
4340 
4341 	      h = elf_link_hash_lookup (htab, name, false, false, true);
4342 
4343 	      /* FIXME: What about bfd_link_hash_common?  */
4344 	      if (h != NULL
4345 		  && (h->root.type == bfd_link_hash_defined
4346 		      || h->root.type == bfd_link_hash_defweak))
4347 		continue;
4348 	    }
4349 
4350 	  sz = s->size;
4351 	  msg = (char *) bfd_alloc (abfd, sz + 1);
4352 	  if (msg == NULL)
4353 	    goto error_return;
4354 
4355 	  if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
4356 	    goto error_return;
4357 
4358 	  msg[sz] = '\0';
4359 
4360 	  if (! (_bfd_generic_link_add_one_symbol
4361 		 (info, abfd, name, BSF_WARNING, s, 0, msg,
4362 		  false, bed->collect, NULL)))
4363 	    goto error_return;
4364 
4365 	  if (bfd_link_executable (info))
4366 	    {
4367 	      /* Clobber the section size so that the warning does
4368 		 not get copied into the output file.  */
4369 	      s->size = 0;
4370 
4371 	      /* Also set SEC_EXCLUDE, so that symbols defined in
4372 		 the warning section don't get copied to the output.  */
4373 	      s->flags |= SEC_EXCLUDE;
4374 	    }
4375 	}
4376     }
4377 
4378   just_syms = ((s = abfd->sections) != NULL
4379 	       && s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS);
4380 
4381   add_needed = true;
4382   if (! dynamic)
4383     {
4384       /* If we are creating a shared library, create all the dynamic
4385 	 sections immediately.  We need to attach them to something,
4386 	 so we attach them to this BFD, provided it is the right
4387 	 format and is not from ld --just-symbols.  Always create the
4388 	 dynamic sections for -E/--dynamic-list.  FIXME: If there
4389 	 are no input BFD's of the same format as the output, we can't
4390 	 make a shared library.  */
4391       if (!just_syms
4392 	  && (bfd_link_pic (info)
4393 	      || (!bfd_link_relocatable (info)
4394 		  && info->nointerp
4395 		  && (info->export_dynamic || info->dynamic)))
4396 	  && is_elf_hash_table (&htab->root)
4397 	  && info->output_bfd->xvec == abfd->xvec
4398 	  && !htab->dynamic_sections_created)
4399 	{
4400 	  if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
4401 	    goto error_return;
4402 	}
4403     }
4404   else if (!is_elf_hash_table (&htab->root))
4405     goto error_return;
4406   else
4407     {
4408       const char *soname = NULL;
4409       char *audit = NULL;
4410       struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
4411       const Elf_Internal_Phdr *phdr;
4412       struct elf_link_loaded_list *loaded_lib;
4413 
4414       /* ld --just-symbols and dynamic objects don't mix very well.
4415 	 ld shouldn't allow it.  */
4416       if (just_syms)
4417 	abort ();
4418 
4419       /* If this dynamic lib was specified on the command line with
4420 	 --as-needed in effect, then we don't want to add a DT_NEEDED
4421 	 tag unless the lib is actually used.  Similary for libs brought
4422 	 in by another lib's DT_NEEDED.  When --no-add-needed is used
4423 	 on a dynamic lib, we don't want to add a DT_NEEDED entry for
4424 	 any dynamic library in DT_NEEDED tags in the dynamic lib at
4425 	 all.  */
4426       add_needed = (elf_dyn_lib_class (abfd)
4427 		    & (DYN_AS_NEEDED | DYN_DT_NEEDED
4428 		       | DYN_NO_NEEDED)) == 0;
4429 
4430       s = bfd_get_section_by_name (abfd, ".dynamic");
4431       if (s != NULL && s->size != 0 && (s->flags & SEC_HAS_CONTENTS) != 0)
4432 	{
4433 	  bfd_byte *dynbuf;
4434 	  bfd_byte *extdyn;
4435 	  unsigned int elfsec;
4436 	  unsigned long shlink;
4437 
4438 	  if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
4439 	    {
4440 	    error_free_dyn:
4441 	      free (dynbuf);
4442 	      goto error_return;
4443 	    }
4444 
4445 	  elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
4446 	  if (elfsec == SHN_BAD)
4447 	    goto error_free_dyn;
4448 	  shlink = elf_elfsections (abfd)[elfsec]->sh_link;
4449 
4450 	  for (extdyn = dynbuf;
4451 	       (size_t) (dynbuf + s->size - extdyn) >= bed->s->sizeof_dyn;
4452 	       extdyn += bed->s->sizeof_dyn)
4453 	    {
4454 	      Elf_Internal_Dyn dyn;
4455 
4456 	      bed->s->swap_dyn_in (abfd, extdyn, &dyn);
4457 	      if (dyn.d_tag == DT_SONAME)
4458 		{
4459 		  unsigned int tagv = dyn.d_un.d_val;
4460 		  soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4461 		  if (soname == NULL)
4462 		    goto error_free_dyn;
4463 		}
4464 	      if (dyn.d_tag == DT_NEEDED)
4465 		{
4466 		  struct bfd_link_needed_list *n, **pn;
4467 		  char *fnm, *anm;
4468 		  unsigned int tagv = dyn.d_un.d_val;
4469 		  size_t amt = sizeof (struct bfd_link_needed_list);
4470 
4471 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4472 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4473 		  if (n == NULL || fnm == NULL)
4474 		    goto error_free_dyn;
4475 		  amt = strlen (fnm) + 1;
4476 		  anm = (char *) bfd_alloc (abfd, amt);
4477 		  if (anm == NULL)
4478 		    goto error_free_dyn;
4479 		  memcpy (anm, fnm, amt);
4480 		  n->name = anm;
4481 		  n->by = abfd;
4482 		  n->next = NULL;
4483 		  for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
4484 		    ;
4485 		  *pn = n;
4486 		}
4487 	      if (dyn.d_tag == DT_RUNPATH)
4488 		{
4489 		  struct bfd_link_needed_list *n, **pn;
4490 		  char *fnm, *anm;
4491 		  unsigned int tagv = dyn.d_un.d_val;
4492 		  size_t amt = sizeof (struct bfd_link_needed_list);
4493 
4494 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4495 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4496 		  if (n == NULL || fnm == NULL)
4497 		    goto error_free_dyn;
4498 		  amt = strlen (fnm) + 1;
4499 		  anm = (char *) bfd_alloc (abfd, amt);
4500 		  if (anm == NULL)
4501 		    goto error_free_dyn;
4502 		  memcpy (anm, fnm, amt);
4503 		  n->name = anm;
4504 		  n->by = abfd;
4505 		  n->next = NULL;
4506 		  for (pn = & runpath;
4507 		       *pn != NULL;
4508 		       pn = &(*pn)->next)
4509 		    ;
4510 		  *pn = n;
4511 		}
4512 	      /* Ignore DT_RPATH if we have seen DT_RUNPATH.  */
4513 	      if (!runpath && dyn.d_tag == DT_RPATH)
4514 		{
4515 		  struct bfd_link_needed_list *n, **pn;
4516 		  char *fnm, *anm;
4517 		  unsigned int tagv = dyn.d_un.d_val;
4518 		  size_t amt = sizeof (struct bfd_link_needed_list);
4519 
4520 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4521 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4522 		  if (n == NULL || fnm == NULL)
4523 		    goto error_free_dyn;
4524 		  amt = strlen (fnm) + 1;
4525 		  anm = (char *) bfd_alloc (abfd, amt);
4526 		  if (anm == NULL)
4527 		    goto error_free_dyn;
4528 		  memcpy (anm, fnm, amt);
4529 		  n->name = anm;
4530 		  n->by = abfd;
4531 		  n->next = NULL;
4532 		  for (pn = & rpath;
4533 		       *pn != NULL;
4534 		       pn = &(*pn)->next)
4535 		    ;
4536 		  *pn = n;
4537 		}
4538 	      if (dyn.d_tag == DT_AUDIT)
4539 		{
4540 		  unsigned int tagv = dyn.d_un.d_val;
4541 		  audit = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4542 		}
4543 	      if (dyn.d_tag == DT_FLAGS_1)
4544 		elf_tdata (abfd)->is_pie = (dyn.d_un.d_val & DF_1_PIE) != 0;
4545 	    }
4546 
4547 	  free (dynbuf);
4548 	}
4549 
4550       /* DT_RUNPATH overrides DT_RPATH.  Do _NOT_ bfd_release, as that
4551 	 frees all more recently bfd_alloc'd blocks as well.  */
4552       if (runpath)
4553 	rpath = runpath;
4554 
4555       if (rpath)
4556 	{
4557 	  struct bfd_link_needed_list **pn;
4558 	  for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
4559 	    ;
4560 	  *pn = rpath;
4561 	}
4562 
4563       /* If we have a PT_GNU_RELRO program header, mark as read-only
4564 	 all sections contained fully therein.  This makes relro
4565 	 shared library sections appear as they will at run-time.  */
4566       phdr = elf_tdata (abfd)->phdr + elf_elfheader (abfd)->e_phnum;
4567       while (phdr-- > elf_tdata (abfd)->phdr)
4568 	if (phdr->p_type == PT_GNU_RELRO)
4569 	  {
4570 	    for (s = abfd->sections; s != NULL; s = s->next)
4571 	      {
4572 		unsigned int opb = bfd_octets_per_byte (abfd, s);
4573 
4574 		if ((s->flags & SEC_ALLOC) != 0
4575 		    && s->vma * opb >= phdr->p_vaddr
4576 		    && s->vma * opb + s->size <= phdr->p_vaddr + phdr->p_memsz)
4577 		  s->flags |= SEC_READONLY;
4578 	      }
4579 	    break;
4580 	  }
4581 
4582       /* We do not want to include any of the sections in a dynamic
4583 	 object in the output file.  We hack by simply clobbering the
4584 	 list of sections in the BFD.  This could be handled more
4585 	 cleanly by, say, a new section flag; the existing
4586 	 SEC_NEVER_LOAD flag is not the one we want, because that one
4587 	 still implies that the section takes up space in the output
4588 	 file.  */
4589       bfd_section_list_clear (abfd);
4590 
4591       /* Find the name to use in a DT_NEEDED entry that refers to this
4592 	 object.  If the object has a DT_SONAME entry, we use it.
4593 	 Otherwise, if the generic linker stuck something in
4594 	 elf_dt_name, we use that.  Otherwise, we just use the file
4595 	 name.  */
4596       if (soname == NULL || *soname == '\0')
4597 	{
4598 	  soname = elf_dt_name (abfd);
4599 	  if (soname == NULL || *soname == '\0')
4600 	    soname = bfd_get_filename (abfd);
4601 	}
4602 
4603       /* Save the SONAME because sometimes the linker emulation code
4604 	 will need to know it.  */
4605       elf_dt_name (abfd) = soname;
4606 
4607       /* If we have already included this dynamic object in the
4608 	 link, just ignore it.  There is no reason to include a
4609 	 particular dynamic object more than once.  */
4610       for (loaded_lib = htab->dyn_loaded;
4611 	   loaded_lib != NULL;
4612 	   loaded_lib = loaded_lib->next)
4613 	{
4614 	  if (strcmp (elf_dt_name (loaded_lib->abfd), soname) == 0)
4615 	    return true;
4616 	}
4617 
4618       /* Create dynamic sections for backends that require that be done
4619 	 before setup_gnu_properties.  */
4620       if (add_needed
4621 	  && !_bfd_elf_link_create_dynamic_sections (abfd, info))
4622 	return false;
4623 
4624       /* Save the DT_AUDIT entry for the linker emulation code. */
4625       elf_dt_audit (abfd) = audit;
4626     }
4627 
4628   /* If this is a dynamic object, we always link against the .dynsym
4629      symbol table, not the .symtab symbol table.  The dynamic linker
4630      will only see the .dynsym symbol table, so there is no reason to
4631      look at .symtab for a dynamic object.  */
4632 
4633   if (! dynamic || elf_dynsymtab (abfd) == 0)
4634     hdr = &elf_tdata (abfd)->symtab_hdr;
4635   else
4636     hdr = &elf_tdata (abfd)->dynsymtab_hdr;
4637 
4638   symcount = hdr->sh_size / bed->s->sizeof_sym;
4639 
4640   /* The sh_info field of the symtab header tells us where the
4641      external symbols start.  We don't care about the local symbols at
4642      this point.  */
4643   if (elf_bad_symtab (abfd))
4644     {
4645       extsymcount = symcount;
4646       extsymoff = 0;
4647     }
4648   else
4649     {
4650       extsymcount = symcount - hdr->sh_info;
4651       extsymoff = hdr->sh_info;
4652     }
4653 
4654   sym_hash = elf_sym_hashes (abfd);
4655   if (extsymcount != 0)
4656     {
4657       isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
4658 				      NULL, NULL, NULL);
4659       if (isymbuf == NULL)
4660 	goto error_return;
4661 
4662       if (sym_hash == NULL)
4663 	{
4664 	  /* We store a pointer to the hash table entry for each
4665 	     external symbol.  */
4666 	  size_t amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4667 	  sym_hash = (struct elf_link_hash_entry **) bfd_zalloc (abfd, amt);
4668 	  if (sym_hash == NULL)
4669 	    goto error_free_sym;
4670 	  elf_sym_hashes (abfd) = sym_hash;
4671 	}
4672     }
4673 
4674   if (dynamic)
4675     {
4676       /* Read in any version definitions.  */
4677       if (!_bfd_elf_slurp_version_tables (abfd,
4678 					  info->default_imported_symver))
4679 	goto error_free_sym;
4680 
4681       /* Read in the symbol versions, but don't bother to convert them
4682 	 to internal format.  */
4683       if (elf_dynversym (abfd) != 0)
4684 	{
4685 	  Elf_Internal_Shdr *versymhdr = &elf_tdata (abfd)->dynversym_hdr;
4686 	  bfd_size_type amt = versymhdr->sh_size;
4687 
4688 	  if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0)
4689 	    goto error_free_sym;
4690 	  extversym = (Elf_External_Versym *)
4691 	    _bfd_malloc_and_read (abfd, amt, amt);
4692 	  if (extversym == NULL)
4693 	    goto error_free_sym;
4694 	  extversym_end = extversym + amt / sizeof (*extversym);
4695 	}
4696     }
4697 
4698   /* If we are loading an as-needed shared lib, save the symbol table
4699      state before we start adding symbols.  If the lib turns out
4700      to be unneeded, restore the state.  */
4701   if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4702     {
4703       unsigned int i;
4704       size_t entsize;
4705 
4706       for (entsize = 0, i = 0; i < htab->root.table.size; i++)
4707 	{
4708 	  struct bfd_hash_entry *p;
4709 	  struct elf_link_hash_entry *h;
4710 
4711 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4712 	    {
4713 	      h = (struct elf_link_hash_entry *) p;
4714 	      entsize += htab->root.table.entsize;
4715 	      if (h->root.type == bfd_link_hash_warning)
4716 		{
4717 		  entsize += htab->root.table.entsize;
4718 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
4719 		}
4720 	      if (h->root.type == bfd_link_hash_common)
4721 		entsize += sizeof (*h->root.u.c.p);
4722 	    }
4723 	}
4724 
4725       tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
4726       old_tab = bfd_malloc (tabsize + entsize);
4727       if (old_tab == NULL)
4728 	goto error_free_vers;
4729 
4730       /* Remember the current objalloc pointer, so that all mem for
4731 	 symbols added can later be reclaimed.  */
4732       alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
4733       if (alloc_mark == NULL)
4734 	goto error_free_vers;
4735 
4736       /* Make a special call to the linker "notice" function to
4737 	 tell it that we are about to handle an as-needed lib.  */
4738       if (!(*bed->notice_as_needed) (abfd, info, notice_as_needed))
4739 	goto error_free_vers;
4740 
4741       /* Clone the symbol table.  Remember some pointers into the
4742 	 symbol table, and dynamic symbol count.  */
4743       old_ent = (char *) old_tab + tabsize;
4744       memcpy (old_tab, htab->root.table.table, tabsize);
4745       old_undefs = htab->root.undefs;
4746       old_undefs_tail = htab->root.undefs_tail;
4747       old_table = htab->root.table.table;
4748       old_size = htab->root.table.size;
4749       old_count = htab->root.table.count;
4750       old_strtab = NULL;
4751       if (htab->dynstr != NULL)
4752 	{
4753 	  old_strtab = _bfd_elf_strtab_save (htab->dynstr);
4754 	  if (old_strtab == NULL)
4755 	    goto error_free_vers;
4756 	}
4757 
4758       for (i = 0; i < htab->root.table.size; i++)
4759 	{
4760 	  struct bfd_hash_entry *p;
4761 	  struct elf_link_hash_entry *h;
4762 
4763 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4764 	    {
4765 	      h = (struct elf_link_hash_entry *) p;
4766 	      memcpy (old_ent, h, htab->root.table.entsize);
4767 	      old_ent = (char *) old_ent + htab->root.table.entsize;
4768 	      if (h->root.type == bfd_link_hash_warning)
4769 		{
4770 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
4771 		  memcpy (old_ent, h, htab->root.table.entsize);
4772 		  old_ent = (char *) old_ent + htab->root.table.entsize;
4773 		}
4774 	      if (h->root.type == bfd_link_hash_common)
4775 		{
4776 		  memcpy (old_ent, h->root.u.c.p, sizeof (*h->root.u.c.p));
4777 		  old_ent = (char *) old_ent + sizeof (*h->root.u.c.p);
4778 		}
4779 	    }
4780 	}
4781     }
4782 
4783   weaks = NULL;
4784   if (extversym == NULL)
4785     ever = NULL;
4786   else if (extversym + extsymoff < extversym_end)
4787     ever = extversym + extsymoff;
4788   else
4789     {
4790       /* xgettext:c-format */
4791       _bfd_error_handler (_("%pB: invalid version offset %lx (max %lx)"),
4792 			  abfd, (long) extsymoff,
4793 			  (long) (extversym_end - extversym) / sizeof (* extversym));
4794       bfd_set_error (bfd_error_bad_value);
4795       goto error_free_vers;
4796     }
4797 
4798   if (!bfd_link_relocatable (info)
4799       && abfd->lto_slim_object)
4800     {
4801       _bfd_error_handler
4802 	(_("%pB: plugin needed to handle lto object"), abfd);
4803     }
4804 
4805   for (isym = isymbuf, isymend = PTR_ADD (isymbuf, extsymcount);
4806        isym < isymend;
4807        isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
4808     {
4809       int bind;
4810       bfd_vma value;
4811       asection *sec, *new_sec;
4812       flagword flags;
4813       const char *name;
4814       struct elf_link_hash_entry *h;
4815       struct elf_link_hash_entry *hi;
4816       bool definition;
4817       bool size_change_ok;
4818       bool type_change_ok;
4819       bool new_weak;
4820       bool old_weak;
4821       bfd *override;
4822       bool common;
4823       bool discarded;
4824       unsigned int old_alignment;
4825       unsigned int shindex;
4826       bfd *old_bfd;
4827       bool matched;
4828 
4829       override = NULL;
4830 
4831       flags = BSF_NO_FLAGS;
4832       sec = NULL;
4833       value = isym->st_value;
4834       common = bed->common_definition (isym);
4835       if (common && info->inhibit_common_definition)
4836 	{
4837 	  /* Treat common symbol as undefined for --no-define-common.  */
4838 	  isym->st_shndx = SHN_UNDEF;
4839 	  common = false;
4840 	}
4841       discarded = false;
4842 
4843       bind = ELF_ST_BIND (isym->st_info);
4844       switch (bind)
4845 	{
4846 	case STB_LOCAL:
4847 	  /* This should be impossible, since ELF requires that all
4848 	     global symbols follow all local symbols, and that sh_info
4849 	     point to the first global symbol.  Unfortunately, Irix 5
4850 	     screws this up.  */
4851 	  if (elf_bad_symtab (abfd))
4852 	    continue;
4853 
4854 	  /* If we aren't prepared to handle locals within the globals
4855 	     then we'll likely segfault on a NULL symbol hash if the
4856 	     symbol is ever referenced in relocations.  */
4857 	  shindex = elf_elfheader (abfd)->e_shstrndx;
4858 	  name = bfd_elf_string_from_elf_section (abfd, shindex, hdr->sh_name);
4859 	  _bfd_error_handler (_("%pB: %s local symbol at index %lu"
4860 				" (>= sh_info of %lu)"),
4861 			      abfd, name, (long) (isym - isymbuf + extsymoff),
4862 			      (long) extsymoff);
4863 
4864 	  /* Dynamic object relocations are not processed by ld, so
4865 	     ld won't run into the problem mentioned above.  */
4866 	  if (dynamic)
4867 	    continue;
4868 	  bfd_set_error (bfd_error_bad_value);
4869 	  goto error_free_vers;
4870 
4871 	case STB_GLOBAL:
4872 	  if (isym->st_shndx != SHN_UNDEF && !common)
4873 	    flags = BSF_GLOBAL;
4874 	  break;
4875 
4876 	case STB_WEAK:
4877 	  flags = BSF_WEAK;
4878 	  break;
4879 
4880 	case STB_GNU_UNIQUE:
4881 	  flags = BSF_GNU_UNIQUE;
4882 	  break;
4883 
4884 	default:
4885 	  /* Leave it up to the processor backend.  */
4886 	  break;
4887 	}
4888 
4889       if (isym->st_shndx == SHN_UNDEF)
4890 	sec = bfd_und_section_ptr;
4891       else if (isym->st_shndx == SHN_ABS)
4892 	sec = bfd_abs_section_ptr;
4893       else if (isym->st_shndx == SHN_COMMON)
4894 	{
4895 	  sec = bfd_com_section_ptr;
4896 	  /* What ELF calls the size we call the value.  What ELF
4897 	     calls the value we call the alignment.  */
4898 	  value = isym->st_size;
4899 	}
4900       else
4901 	{
4902 	  sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
4903 	  if (sec == NULL)
4904 	    sec = bfd_abs_section_ptr;
4905 	  else if (discarded_section (sec))
4906 	    {
4907 	      /* Symbols from discarded section are undefined.  We keep
4908 		 its visibility.  */
4909 	      sec = bfd_und_section_ptr;
4910 	      discarded = true;
4911 	      isym->st_shndx = SHN_UNDEF;
4912 	    }
4913 	  else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
4914 	    value -= sec->vma;
4915 	}
4916 
4917       name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
4918 					      isym->st_name);
4919       if (name == NULL)
4920 	goto error_free_vers;
4921 
4922       if (isym->st_shndx == SHN_COMMON
4923 	  && (abfd->flags & BFD_PLUGIN) != 0)
4924 	{
4925 	  asection *xc = bfd_get_section_by_name (abfd, "COMMON");
4926 
4927 	  if (xc == NULL)
4928 	    {
4929 	      flagword sflags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP
4930 				 | SEC_EXCLUDE);
4931 	      xc = bfd_make_section_with_flags (abfd, "COMMON", sflags);
4932 	      if (xc == NULL)
4933 		goto error_free_vers;
4934 	    }
4935 	  sec = xc;
4936 	}
4937       else if (isym->st_shndx == SHN_COMMON
4938 	       && ELF_ST_TYPE (isym->st_info) == STT_TLS
4939 	       && !bfd_link_relocatable (info))
4940 	{
4941 	  asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
4942 
4943 	  if (tcomm == NULL)
4944 	    {
4945 	      flagword sflags = (SEC_ALLOC | SEC_THREAD_LOCAL | SEC_IS_COMMON
4946 				 | SEC_LINKER_CREATED);
4947 	      tcomm = bfd_make_section_with_flags (abfd, ".tcommon", sflags);
4948 	      if (tcomm == NULL)
4949 		goto error_free_vers;
4950 	    }
4951 	  sec = tcomm;
4952 	}
4953       else if (bed->elf_add_symbol_hook)
4954 	{
4955 	  if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
4956 					     &sec, &value))
4957 	    goto error_free_vers;
4958 
4959 	  /* The hook function sets the name to NULL if this symbol
4960 	     should be skipped for some reason.  */
4961 	  if (name == NULL)
4962 	    continue;
4963 	}
4964 
4965       /* Sanity check that all possibilities were handled.  */
4966       if (sec == NULL)
4967 	abort ();
4968 
4969       /* Silently discard TLS symbols from --just-syms.  There's
4970 	 no way to combine a static TLS block with a new TLS block
4971 	 for this executable.  */
4972       if (ELF_ST_TYPE (isym->st_info) == STT_TLS
4973 	  && sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
4974 	continue;
4975 
4976       if (bfd_is_und_section (sec)
4977 	  || bfd_is_com_section (sec))
4978 	definition = false;
4979       else
4980 	definition = true;
4981 
4982       size_change_ok = false;
4983       type_change_ok = bed->type_change_ok;
4984       old_weak = false;
4985       matched = false;
4986       old_alignment = 0;
4987       old_bfd = NULL;
4988       new_sec = sec;
4989 
4990       if (is_elf_hash_table (&htab->root))
4991 	{
4992 	  Elf_Internal_Versym iver;
4993 	  unsigned int vernum = 0;
4994 	  bool skip;
4995 
4996 	  if (ever == NULL)
4997 	    {
4998 	      if (info->default_imported_symver)
4999 		/* Use the default symbol version created earlier.  */
5000 		iver.vs_vers = elf_tdata (abfd)->cverdefs;
5001 	      else
5002 		iver.vs_vers = 0;
5003 	    }
5004 	  else if (ever >= extversym_end)
5005 	    {
5006 	      /* xgettext:c-format */
5007 	      _bfd_error_handler (_("%pB: not enough version information"),
5008 				  abfd);
5009 	      bfd_set_error (bfd_error_bad_value);
5010 	      goto error_free_vers;
5011 	    }
5012 	  else
5013 	    _bfd_elf_swap_versym_in (abfd, ever, &iver);
5014 
5015 	  vernum = iver.vs_vers & VERSYM_VERSION;
5016 
5017 	  /* If this is a hidden symbol, or if it is not version
5018 	     1, we append the version name to the symbol name.
5019 	     However, we do not modify a non-hidden absolute symbol
5020 	     if it is not a function, because it might be the version
5021 	     symbol itself.  FIXME: What if it isn't?  */
5022 	  if ((iver.vs_vers & VERSYM_HIDDEN) != 0
5023 	      || (vernum > 1
5024 		  && (!bfd_is_abs_section (sec)
5025 		      || bed->is_function_type (ELF_ST_TYPE (isym->st_info)))))
5026 	    {
5027 	      const char *verstr;
5028 	      size_t namelen, verlen, newlen;
5029 	      char *newname, *p;
5030 
5031 	      if (isym->st_shndx != SHN_UNDEF)
5032 		{
5033 		  if (vernum > elf_tdata (abfd)->cverdefs)
5034 		    verstr = NULL;
5035 		  else if (vernum > 1)
5036 		    verstr =
5037 		      elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
5038 		  else
5039 		    verstr = "";
5040 
5041 		  if (verstr == NULL)
5042 		    {
5043 		      _bfd_error_handler
5044 			/* xgettext:c-format */
5045 			(_("%pB: %s: invalid version %u (max %d)"),
5046 			 abfd, name, vernum,
5047 			 elf_tdata (abfd)->cverdefs);
5048 		      bfd_set_error (bfd_error_bad_value);
5049 		      goto error_free_vers;
5050 		    }
5051 		}
5052 	      else
5053 		{
5054 		  /* We cannot simply test for the number of
5055 		     entries in the VERNEED section since the
5056 		     numbers for the needed versions do not start
5057 		     at 0.  */
5058 		  Elf_Internal_Verneed *t;
5059 
5060 		  verstr = NULL;
5061 		  for (t = elf_tdata (abfd)->verref;
5062 		       t != NULL;
5063 		       t = t->vn_nextref)
5064 		    {
5065 		      Elf_Internal_Vernaux *a;
5066 
5067 		      for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5068 			{
5069 			  if (a->vna_other == vernum)
5070 			    {
5071 			      verstr = a->vna_nodename;
5072 			      break;
5073 			    }
5074 			}
5075 		      if (a != NULL)
5076 			break;
5077 		    }
5078 		  if (verstr == NULL)
5079 		    {
5080 		      _bfd_error_handler
5081 			/* xgettext:c-format */
5082 			(_("%pB: %s: invalid needed version %d"),
5083 			 abfd, name, vernum);
5084 		      bfd_set_error (bfd_error_bad_value);
5085 		      goto error_free_vers;
5086 		    }
5087 		}
5088 
5089 	      namelen = strlen (name);
5090 	      verlen = strlen (verstr);
5091 	      newlen = namelen + verlen + 2;
5092 	      if ((iver.vs_vers & VERSYM_HIDDEN) == 0
5093 		  && isym->st_shndx != SHN_UNDEF)
5094 		++newlen;
5095 
5096 	      newname = (char *) bfd_hash_allocate (&htab->root.table, newlen);
5097 	      if (newname == NULL)
5098 		goto error_free_vers;
5099 	      memcpy (newname, name, namelen);
5100 	      p = newname + namelen;
5101 	      *p++ = ELF_VER_CHR;
5102 	      /* If this is a defined non-hidden version symbol,
5103 		 we add another @ to the name.  This indicates the
5104 		 default version of the symbol.  */
5105 	      if ((iver.vs_vers & VERSYM_HIDDEN) == 0
5106 		  && isym->st_shndx != SHN_UNDEF)
5107 		*p++ = ELF_VER_CHR;
5108 	      memcpy (p, verstr, verlen + 1);
5109 
5110 	      name = newname;
5111 	    }
5112 
5113 	  /* If this symbol has default visibility and the user has
5114 	     requested we not re-export it, then mark it as hidden.  */
5115 	  if (!bfd_is_und_section (sec)
5116 	      && !dynamic
5117 	      && abfd->no_export
5118 	      && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
5119 	    isym->st_other = (STV_HIDDEN
5120 			      | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
5121 
5122 	  if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec, &value,
5123 				      sym_hash, &old_bfd, &old_weak,
5124 				      &old_alignment, &skip, &override,
5125 				      &type_change_ok, &size_change_ok,
5126 				      &matched))
5127 	    goto error_free_vers;
5128 
5129 	  if (skip)
5130 	    continue;
5131 
5132 	  /* Override a definition only if the new symbol matches the
5133 	     existing one.  */
5134 	  if (override && matched)
5135 	    definition = false;
5136 
5137 	  h = *sym_hash;
5138 	  while (h->root.type == bfd_link_hash_indirect
5139 		 || h->root.type == bfd_link_hash_warning)
5140 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
5141 
5142 	  if (h->versioned != unversioned
5143 	      && elf_tdata (abfd)->verdef != NULL
5144 	      && vernum > 1
5145 	      && definition)
5146 	    h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
5147 	}
5148 
5149       if (! (_bfd_generic_link_add_one_symbol
5150 	     (info, override ? override : abfd, name, flags, sec, value,
5151 	      NULL, false, bed->collect,
5152 	      (struct bfd_link_hash_entry **) sym_hash)))
5153 	goto error_free_vers;
5154 
5155       h = *sym_hash;
5156       /* We need to make sure that indirect symbol dynamic flags are
5157 	 updated.  */
5158       hi = h;
5159       while (h->root.type == bfd_link_hash_indirect
5160 	     || h->root.type == bfd_link_hash_warning)
5161 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
5162 
5163       *sym_hash = h;
5164 
5165       /* Setting the index to -3 tells elf_link_output_extsym that
5166 	 this symbol is defined in a discarded section.  */
5167       if (discarded && is_elf_hash_table (&htab->root))
5168 	h->indx = -3;
5169 
5170       new_weak = (flags & BSF_WEAK) != 0;
5171       if (dynamic
5172 	  && definition
5173 	  && new_weak
5174 	  && !bed->is_function_type (ELF_ST_TYPE (isym->st_info))
5175 	  && is_elf_hash_table (&htab->root)
5176 	  && h->u.alias == NULL)
5177 	{
5178 	  /* Keep a list of all weak defined non function symbols from
5179 	     a dynamic object, using the alias field.  Later in this
5180 	     function we will set the alias field to the correct
5181 	     value.  We only put non-function symbols from dynamic
5182 	     objects on this list, because that happens to be the only
5183 	     time we need to know the normal symbol corresponding to a
5184 	     weak symbol, and the information is time consuming to
5185 	     figure out.  If the alias field is not already NULL,
5186 	     then this symbol was already defined by some previous
5187 	     dynamic object, and we will be using that previous
5188 	     definition anyhow.  */
5189 
5190 	  h->u.alias = weaks;
5191 	  weaks = h;
5192 	}
5193 
5194       /* Set the alignment of a common symbol.  */
5195       if ((common || bfd_is_com_section (sec))
5196 	  && h->root.type == bfd_link_hash_common)
5197 	{
5198 	  unsigned int align;
5199 
5200 	  if (common)
5201 	    align = bfd_log2 (isym->st_value);
5202 	  else
5203 	    {
5204 	      /* The new symbol is a common symbol in a shared object.
5205 		 We need to get the alignment from the section.  */
5206 	      align = new_sec->alignment_power;
5207 	    }
5208 	  if (align > old_alignment)
5209 	    h->root.u.c.p->alignment_power = align;
5210 	  else
5211 	    h->root.u.c.p->alignment_power = old_alignment;
5212 	}
5213 
5214       if (is_elf_hash_table (&htab->root))
5215 	{
5216 	  /* Set a flag in the hash table entry indicating the type of
5217 	     reference or definition we just found.  A dynamic symbol
5218 	     is one which is referenced or defined by both a regular
5219 	     object and a shared object.  */
5220 	  bool dynsym = false;
5221 
5222 	  /* Plugin symbols aren't normal.  Don't set def/ref flags.  */
5223 	  if ((abfd->flags & BFD_PLUGIN) != 0)
5224 	    {
5225 	      /* Except for this flag to track nonweak references.  */
5226 	      if (!definition
5227 		  && bind != STB_WEAK)
5228 		h->ref_ir_nonweak = 1;
5229 	    }
5230 	  else if (!dynamic)
5231 	    {
5232 	      if (! definition)
5233 		{
5234 		  h->ref_regular = 1;
5235 		  if (bind != STB_WEAK)
5236 		    h->ref_regular_nonweak = 1;
5237 		}
5238 	      else
5239 		{
5240 		  h->def_regular = 1;
5241 		  if (h->def_dynamic)
5242 		    {
5243 		      h->def_dynamic = 0;
5244 		      h->ref_dynamic = 1;
5245 		    }
5246 		}
5247 	    }
5248 	  else
5249 	    {
5250 	      if (! definition)
5251 		{
5252 		  h->ref_dynamic = 1;
5253 		  hi->ref_dynamic = 1;
5254 		}
5255 	      else
5256 		{
5257 		  h->def_dynamic = 1;
5258 		  hi->def_dynamic = 1;
5259 		}
5260 	    }
5261 
5262 	  /* If an indirect symbol has been forced local, don't
5263 	     make the real symbol dynamic.  */
5264 	  if (h != hi && hi->forced_local)
5265 	    ;
5266 	  else if (!dynamic)
5267 	    {
5268 	      if (bfd_link_dll (info)
5269 		  || h->def_dynamic
5270 		  || h->ref_dynamic)
5271 		dynsym = true;
5272 	    }
5273 	  else
5274 	    {
5275 	      if (h->def_regular
5276 		  || h->ref_regular
5277 		  || (h->is_weakalias
5278 		      && weakdef (h)->dynindx != -1))
5279 		dynsym = true;
5280 	    }
5281 
5282 	  /* Check to see if we need to add an indirect symbol for
5283 	     the default name.  */
5284 	  if ((definition
5285 	       || (!override && h->root.type == bfd_link_hash_common))
5286 	      && !(hi != h
5287 		   && hi->versioned == versioned_hidden))
5288 	    if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
5289 					      sec, value, &old_bfd, &dynsym))
5290 	      goto error_free_vers;
5291 
5292 	  /* Check the alignment when a common symbol is involved. This
5293 	     can change when a common symbol is overridden by a normal
5294 	     definition or a common symbol is ignored due to the old
5295 	     normal definition. We need to make sure the maximum
5296 	     alignment is maintained.  */
5297 	  if ((old_alignment || common)
5298 	      && h->root.type != bfd_link_hash_common)
5299 	    {
5300 	      unsigned int common_align;
5301 	      unsigned int normal_align;
5302 	      unsigned int symbol_align;
5303 	      bfd *normal_bfd;
5304 	      bfd *common_bfd;
5305 
5306 	      BFD_ASSERT (h->root.type == bfd_link_hash_defined
5307 			  || h->root.type == bfd_link_hash_defweak);
5308 
5309 	      symbol_align = ffs (h->root.u.def.value) - 1;
5310 	      if (h->root.u.def.section->owner != NULL
5311 		  && (h->root.u.def.section->owner->flags
5312 		       & (DYNAMIC | BFD_PLUGIN)) == 0)
5313 		{
5314 		  normal_align = h->root.u.def.section->alignment_power;
5315 		  if (normal_align > symbol_align)
5316 		    normal_align = symbol_align;
5317 		}
5318 	      else
5319 		normal_align = symbol_align;
5320 
5321 	      if (old_alignment)
5322 		{
5323 		  common_align = old_alignment;
5324 		  common_bfd = old_bfd;
5325 		  normal_bfd = abfd;
5326 		}
5327 	      else
5328 		{
5329 		  common_align = bfd_log2 (isym->st_value);
5330 		  common_bfd = abfd;
5331 		  normal_bfd = old_bfd;
5332 		}
5333 
5334 	      if (normal_align < common_align)
5335 		{
5336 		  /* PR binutils/2735 */
5337 		  if (normal_bfd == NULL)
5338 		    _bfd_error_handler
5339 		      /* xgettext:c-format */
5340 		      (_("warning: alignment %u of common symbol `%s' in %pB is"
5341 			 " greater than the alignment (%u) of its section %pA"),
5342 		       1 << common_align, name, common_bfd,
5343 		       1 << normal_align, h->root.u.def.section);
5344 		  else
5345 		    _bfd_error_handler
5346 		      /* xgettext:c-format */
5347 		      (_("warning: alignment %u of normal symbol `%s' in %pB"
5348 			 " is smaller than %u used by the common definition in %pB"),
5349 		       1 << normal_align, name, normal_bfd,
5350 		       1 << common_align, common_bfd);
5351 
5352 		  /* PR 30499: make sure that users understand that this warning is serious.  */
5353 		  _bfd_error_handler
5354 		    (_("warning: NOTE: alignment discrepancies can cause real problems.  Investigation is advised."));
5355 		}
5356 	    }
5357 
5358 	  /* Remember the symbol size if it isn't undefined.  */
5359 	  if (isym->st_size != 0
5360 	      && isym->st_shndx != SHN_UNDEF
5361 	      && (definition || h->size == 0))
5362 	    {
5363 	      if (h->size != 0
5364 		  && h->size != isym->st_size
5365 		  && ! size_change_ok)
5366 		{
5367 		  _bfd_error_handler
5368 		    /* xgettext:c-format */
5369 		    (_("warning: size of symbol `%s' changed"
5370 		       " from %" PRIu64 " in %pB to %" PRIu64 " in %pB"),
5371 		     name, (uint64_t) h->size, old_bfd,
5372 		     (uint64_t) isym->st_size, abfd);
5373 
5374 		  /* PR 30499: make sure that users understand that this warning is serious.  */
5375 		  _bfd_error_handler
5376 		    (_("warning: NOTE: size discrepancies can cause real problems.  Investigation is advised."));
5377 		}
5378 
5379 	      h->size = isym->st_size;
5380 	    }
5381 
5382 	  /* If this is a common symbol, then we always want H->SIZE
5383 	     to be the size of the common symbol.  The code just above
5384 	     won't fix the size if a common symbol becomes larger.  We
5385 	     don't warn about a size change here, because that is
5386 	     covered by --warn-common.  Allow changes between different
5387 	     function types.  */
5388 	  if (h->root.type == bfd_link_hash_common)
5389 	    h->size = h->root.u.c.size;
5390 
5391 	  if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
5392 	      && ((definition && !new_weak)
5393 		  || (old_weak && h->root.type == bfd_link_hash_common)
5394 		  || h->type == STT_NOTYPE))
5395 	    {
5396 	      unsigned int type = ELF_ST_TYPE (isym->st_info);
5397 
5398 	      /* Turn an IFUNC symbol from a DSO into a normal FUNC
5399 		 symbol.  */
5400 	      if (type == STT_GNU_IFUNC
5401 		  && (abfd->flags & DYNAMIC) != 0)
5402 		type = STT_FUNC;
5403 
5404 	      if (h->type != type)
5405 		{
5406 		  if (h->type != STT_NOTYPE && ! type_change_ok)
5407 		    /* xgettext:c-format */
5408 		    _bfd_error_handler
5409 		      (_("warning: type of symbol `%s' changed"
5410 			 " from %d to %d in %pB"),
5411 		       name, h->type, type, abfd);
5412 
5413 		  h->type = type;
5414 		}
5415 	    }
5416 
5417 	  /* Merge st_other field.  */
5418 	  elf_merge_st_other (abfd, h, isym->st_other, sec,
5419 			      definition, dynamic);
5420 
5421 	  /* We don't want to make debug symbol dynamic.  */
5422 	  if (definition
5423 	      && (sec->flags & SEC_DEBUGGING)
5424 	      && !bfd_link_relocatable (info))
5425 	    dynsym = false;
5426 
5427 	  /* Nor should we make plugin symbols dynamic.  */
5428 	  if ((abfd->flags & BFD_PLUGIN) != 0)
5429 	    dynsym = false;
5430 
5431 	  if (definition)
5432 	    {
5433 	      h->target_internal = isym->st_target_internal;
5434 	      h->unique_global = (flags & BSF_GNU_UNIQUE) != 0;
5435 	    }
5436 
5437 	  /* Don't add indirect symbols for .symver x, x@FOO aliases
5438 	     in IR.  Since all data or text symbols in IR have the
5439 	     same type, value and section, we can't tell if a symbol
5440 	     is an alias of another symbol by their types, values and
5441 	     sections.  */
5442 	  if (definition
5443 	      && !dynamic
5444 	      && (abfd->flags & BFD_PLUGIN) == 0)
5445 	    {
5446 	      char *p = strchr (name, ELF_VER_CHR);
5447 	      if (p != NULL && p[1] != ELF_VER_CHR)
5448 		{
5449 		  /* Queue non-default versions so that .symver x, x@FOO
5450 		     aliases can be checked.  */
5451 		  if (!nondeflt_vers)
5452 		    {
5453 		      size_t amt = ((isymend - isym + 1)
5454 				    * sizeof (struct elf_link_hash_entry *));
5455 		      nondeflt_vers
5456 			= (struct elf_link_hash_entry **) bfd_malloc (amt);
5457 		      if (!nondeflt_vers)
5458 			goto error_free_vers;
5459 		    }
5460 		  nondeflt_vers[nondeflt_vers_cnt++] = h;
5461 		}
5462 	    }
5463 
5464 	  if (dynsym && h->dynindx == -1)
5465 	    {
5466 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
5467 		goto error_free_vers;
5468 	      if (h->is_weakalias
5469 		  && weakdef (h)->dynindx == -1)
5470 		{
5471 		  if (!bfd_elf_link_record_dynamic_symbol (info, weakdef (h)))
5472 		    goto error_free_vers;
5473 		}
5474 	    }
5475 	  else if (h->dynindx != -1)
5476 	    /* If the symbol already has a dynamic index, but
5477 	       visibility says it should not be visible, turn it into
5478 	       a local symbol.  */
5479 	    switch (ELF_ST_VISIBILITY (h->other))
5480 	      {
5481 	      case STV_INTERNAL:
5482 	      case STV_HIDDEN:
5483 		(*bed->elf_backend_hide_symbol) (info, h, true);
5484 		dynsym = false;
5485 		break;
5486 	      }
5487 
5488 	  if (!add_needed
5489 	      && matched
5490 	      && definition
5491 	      && h->root.type != bfd_link_hash_indirect
5492 	      && ((dynsym
5493 		   && h->ref_regular_nonweak)
5494 		  || (old_bfd != NULL
5495 		      && (old_bfd->flags & BFD_PLUGIN) != 0
5496 		      && h->ref_ir_nonweak
5497 		      && !info->lto_all_symbols_read)
5498 		  || (h->ref_dynamic_nonweak
5499 		      && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0
5500 		      && !on_needed_list (elf_dt_name (abfd),
5501 					  htab->needed, NULL))))
5502 	    {
5503 	      const char *soname = elf_dt_name (abfd);
5504 
5505 	      info->callbacks->minfo ("%!", soname, old_bfd,
5506 				      h->root.root.string);
5507 
5508 	      /* A symbol from a library loaded via DT_NEEDED of some
5509 		 other library is referenced by a regular object.
5510 		 Add a DT_NEEDED entry for it.  Issue an error if
5511 		 --no-add-needed is used and the reference was not
5512 		 a weak one.  */
5513 	      if (old_bfd != NULL
5514 		  && (elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
5515 		{
5516 		  _bfd_error_handler
5517 		    /* xgettext:c-format */
5518 		    (_("%pB: undefined reference to symbol '%s'"),
5519 		     old_bfd, name);
5520 		  bfd_set_error (bfd_error_missing_dso);
5521 		  goto error_free_vers;
5522 		}
5523 
5524 	      elf_dyn_lib_class (abfd) = (enum dynamic_lib_link_class)
5525 		(elf_dyn_lib_class (abfd) & ~DYN_AS_NEEDED);
5526 
5527 	      /* Create dynamic sections for backends that require
5528 		 that be done before setup_gnu_properties.  */
5529 	      if (!_bfd_elf_link_create_dynamic_sections (abfd, info))
5530 		return false;
5531 	      add_needed = true;
5532 	    }
5533 	}
5534     }
5535 
5536   if (info->lto_plugin_active
5537       && !bfd_link_relocatable (info)
5538       && (abfd->flags & BFD_PLUGIN) == 0
5539       && !just_syms
5540       && extsymcount)
5541     {
5542       int r_sym_shift;
5543 
5544       if (bed->s->arch_size == 32)
5545 	r_sym_shift = 8;
5546       else
5547 	r_sym_shift = 32;
5548 
5549       /* If linker plugin is enabled, set non_ir_ref_regular on symbols
5550 	 referenced in regular objects so that linker plugin will get
5551 	 the correct symbol resolution.  */
5552 
5553       sym_hash = elf_sym_hashes (abfd);
5554       for (s = abfd->sections; s != NULL; s = s->next)
5555 	{
5556 	  Elf_Internal_Rela *internal_relocs;
5557 	  Elf_Internal_Rela *rel, *relend;
5558 
5559 	  /* Don't check relocations in excluded sections.  */
5560 	  if ((s->flags & SEC_RELOC) == 0
5561 	      || s->reloc_count == 0
5562 	      || (s->flags & SEC_EXCLUDE) != 0
5563 	      || ((info->strip == strip_all
5564 		   || info->strip == strip_debugger)
5565 		  && (s->flags & SEC_DEBUGGING) != 0))
5566 	    continue;
5567 
5568 	  internal_relocs = _bfd_elf_link_info_read_relocs (abfd, info,
5569 							    s, NULL,
5570 							    NULL,
5571 							    _bfd_link_keep_memory (info));
5572 	  if (internal_relocs == NULL)
5573 	    goto error_free_vers;
5574 
5575 	  rel = internal_relocs;
5576 	  relend = rel + s->reloc_count;
5577 	  for ( ; rel < relend; rel++)
5578 	    {
5579 	      unsigned long r_symndx = rel->r_info >> r_sym_shift;
5580 	      struct elf_link_hash_entry *h;
5581 
5582 	      /* Skip local symbols.  */
5583 	      if (r_symndx < extsymoff)
5584 		continue;
5585 
5586 	      h = sym_hash[r_symndx - extsymoff];
5587 	      if (h != NULL)
5588 		h->root.non_ir_ref_regular = 1;
5589 	    }
5590 
5591 	  if (elf_section_data (s)->relocs != internal_relocs)
5592 	    free (internal_relocs);
5593 	}
5594     }
5595 
5596   free (extversym);
5597   extversym = NULL;
5598   free (isymbuf);
5599   isymbuf = NULL;
5600 
5601   if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
5602     {
5603       unsigned int i;
5604 
5605       /* Restore the symbol table.  */
5606       old_ent = (char *) old_tab + tabsize;
5607       memset (elf_sym_hashes (abfd), 0,
5608 	      extsymcount * sizeof (struct elf_link_hash_entry *));
5609       htab->root.table.table = old_table;
5610       htab->root.table.size = old_size;
5611       htab->root.table.count = old_count;
5612       memcpy (htab->root.table.table, old_tab, tabsize);
5613       htab->root.undefs = old_undefs;
5614       htab->root.undefs_tail = old_undefs_tail;
5615       if (htab->dynstr != NULL)
5616 	_bfd_elf_strtab_restore (htab->dynstr, old_strtab);
5617       free (old_strtab);
5618       old_strtab = NULL;
5619       for (i = 0; i < htab->root.table.size; i++)
5620 	{
5621 	  struct bfd_hash_entry *p;
5622 	  struct elf_link_hash_entry *h;
5623 	  unsigned int non_ir_ref_dynamic;
5624 
5625 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
5626 	    {
5627 	      /* Preserve non_ir_ref_dynamic so that this symbol
5628 		 will be exported when the dynamic lib becomes needed
5629 		 in the second pass.  */
5630 	      h = (struct elf_link_hash_entry *) p;
5631 	      if (h->root.type == bfd_link_hash_warning)
5632 		h = (struct elf_link_hash_entry *) h->root.u.i.link;
5633 	      non_ir_ref_dynamic = h->root.non_ir_ref_dynamic;
5634 
5635 	      h = (struct elf_link_hash_entry *) p;
5636 	      memcpy (h, old_ent, htab->root.table.entsize);
5637 	      old_ent = (char *) old_ent + htab->root.table.entsize;
5638 	      if (h->root.type == bfd_link_hash_warning)
5639 		{
5640 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
5641 		  memcpy (h, old_ent, htab->root.table.entsize);
5642 		  old_ent = (char *) old_ent + htab->root.table.entsize;
5643 		}
5644 	      if (h->root.type == bfd_link_hash_common)
5645 		{
5646 		  memcpy (h->root.u.c.p, old_ent, sizeof (*h->root.u.c.p));
5647 		  old_ent = (char *) old_ent + sizeof (*h->root.u.c.p);
5648 		}
5649 	      h->root.non_ir_ref_dynamic = non_ir_ref_dynamic;
5650 	    }
5651 	}
5652 
5653       /* Make a special call to the linker "notice" function to
5654 	 tell it that symbols added for crefs may need to be removed.  */
5655       if (!(*bed->notice_as_needed) (abfd, info, notice_not_needed))
5656 	goto error_free_vers;
5657 
5658       free (old_tab);
5659       objalloc_free_block ((struct objalloc *) htab->root.table.memory,
5660 			   alloc_mark);
5661       free (nondeflt_vers);
5662       return true;
5663     }
5664 
5665   if (old_tab != NULL)
5666     {
5667       if (!(*bed->notice_as_needed) (abfd, info, notice_needed))
5668 	goto error_free_vers;
5669       free (old_tab);
5670       old_tab = NULL;
5671     }
5672 
5673   /* Now that all the symbols from this input file are created, if
5674      not performing a relocatable link, handle .symver foo, foo@BAR
5675      such that any relocs against foo become foo@BAR.  */
5676   if (!bfd_link_relocatable (info) && nondeflt_vers != NULL)
5677     {
5678       size_t cnt, symidx;
5679 
5680       for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
5681 	{
5682 	  struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
5683 	  char *shortname, *p;
5684 	  size_t amt;
5685 
5686 	  p = strchr (h->root.root.string, ELF_VER_CHR);
5687 	  if (p == NULL
5688 	      || (h->root.type != bfd_link_hash_defined
5689 		  && h->root.type != bfd_link_hash_defweak))
5690 	    continue;
5691 
5692 	  amt = p - h->root.root.string;
5693 	  shortname = (char *) bfd_malloc (amt + 1);
5694 	  if (!shortname)
5695 	    goto error_free_vers;
5696 	  memcpy (shortname, h->root.root.string, amt);
5697 	  shortname[amt] = '\0';
5698 
5699 	  hi = (struct elf_link_hash_entry *)
5700 	       bfd_link_hash_lookup (&htab->root, shortname,
5701 				     false, false, false);
5702 	  if (hi != NULL
5703 	      && hi->root.type == h->root.type
5704 	      && hi->root.u.def.value == h->root.u.def.value
5705 	      && hi->root.u.def.section == h->root.u.def.section)
5706 	    {
5707 	      (*bed->elf_backend_hide_symbol) (info, hi, true);
5708 	      hi->root.type = bfd_link_hash_indirect;
5709 	      hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
5710 	      (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
5711 	      sym_hash = elf_sym_hashes (abfd);
5712 	      if (sym_hash)
5713 		for (symidx = 0; symidx < extsymcount; ++symidx)
5714 		  if (sym_hash[symidx] == hi)
5715 		    {
5716 		      sym_hash[symidx] = h;
5717 		      break;
5718 		    }
5719 	    }
5720 	  free (shortname);
5721 	}
5722       free (nondeflt_vers);
5723       nondeflt_vers = NULL;
5724     }
5725 
5726   /* Now set the alias field correctly for all the weak defined
5727      symbols we found.  The only way to do this is to search all the
5728      symbols.  Since we only need the information for non functions in
5729      dynamic objects, that's the only time we actually put anything on
5730      the list WEAKS.  We need this information so that if a regular
5731      object refers to a symbol defined weakly in a dynamic object, the
5732      real symbol in the dynamic object is also put in the dynamic
5733      symbols; we also must arrange for both symbols to point to the
5734      same memory location.  We could handle the general case of symbol
5735      aliasing, but a general symbol alias can only be generated in
5736      assembler code, handling it correctly would be very time
5737      consuming, and other ELF linkers don't handle general aliasing
5738      either.  */
5739   if (weaks != NULL)
5740     {
5741       struct elf_link_hash_entry **hpp;
5742       struct elf_link_hash_entry **hppend;
5743       struct elf_link_hash_entry **sorted_sym_hash;
5744       struct elf_link_hash_entry *h;
5745       size_t sym_count, amt;
5746 
5747       /* Since we have to search the whole symbol list for each weak
5748 	 defined symbol, search time for N weak defined symbols will be
5749 	 O(N^2). Binary search will cut it down to O(NlogN).  */
5750       amt = extsymcount * sizeof (*sorted_sym_hash);
5751       sorted_sym_hash = bfd_malloc (amt);
5752       if (sorted_sym_hash == NULL)
5753 	goto error_return;
5754       sym_hash = sorted_sym_hash;
5755       hpp = elf_sym_hashes (abfd);
5756       hppend = hpp + extsymcount;
5757       sym_count = 0;
5758       for (; hpp < hppend; hpp++)
5759 	{
5760 	  h = *hpp;
5761 	  if (h != NULL
5762 	      && h->root.type == bfd_link_hash_defined
5763 	      && !bed->is_function_type (h->type))
5764 	    {
5765 	      *sym_hash = h;
5766 	      sym_hash++;
5767 	      sym_count++;
5768 	    }
5769 	}
5770 
5771       qsort (sorted_sym_hash, sym_count, sizeof (*sorted_sym_hash),
5772 	     elf_sort_symbol);
5773 
5774       while (weaks != NULL)
5775 	{
5776 	  struct elf_link_hash_entry *hlook;
5777 	  asection *slook;
5778 	  bfd_vma vlook;
5779 	  size_t i, j, idx = 0;
5780 
5781 	  hlook = weaks;
5782 	  weaks = hlook->u.alias;
5783 	  hlook->u.alias = NULL;
5784 
5785 	  if (hlook->root.type != bfd_link_hash_defined
5786 	      && hlook->root.type != bfd_link_hash_defweak)
5787 	    continue;
5788 
5789 	  slook = hlook->root.u.def.section;
5790 	  vlook = hlook->root.u.def.value;
5791 
5792 	  i = 0;
5793 	  j = sym_count;
5794 	  while (i != j)
5795 	    {
5796 	      bfd_signed_vma vdiff;
5797 	      idx = (i + j) / 2;
5798 	      h = sorted_sym_hash[idx];
5799 	      vdiff = vlook - h->root.u.def.value;
5800 	      if (vdiff < 0)
5801 		j = idx;
5802 	      else if (vdiff > 0)
5803 		i = idx + 1;
5804 	      else
5805 		{
5806 		  int sdiff = slook->id - h->root.u.def.section->id;
5807 		  if (sdiff < 0)
5808 		    j = idx;
5809 		  else if (sdiff > 0)
5810 		    i = idx + 1;
5811 		  else
5812 		    break;
5813 		}
5814 	    }
5815 
5816 	  /* We didn't find a value/section match.  */
5817 	  if (i == j)
5818 	    continue;
5819 
5820 	  /* With multiple aliases, or when the weak symbol is already
5821 	     strongly defined, we have multiple matching symbols and
5822 	     the binary search above may land on any of them.  Step
5823 	     one past the matching symbol(s).  */
5824 	  while (++idx != j)
5825 	    {
5826 	      h = sorted_sym_hash[idx];
5827 	      if (h->root.u.def.section != slook
5828 		  || h->root.u.def.value != vlook)
5829 		break;
5830 	    }
5831 
5832 	  /* Now look back over the aliases.  Since we sorted by size
5833 	     as well as value and section, we'll choose the one with
5834 	     the largest size.  */
5835 	  while (idx-- != i)
5836 	    {
5837 	      h = sorted_sym_hash[idx];
5838 
5839 	      /* Stop if value or section doesn't match.  */
5840 	      if (h->root.u.def.section != slook
5841 		  || h->root.u.def.value != vlook)
5842 		break;
5843 	      else if (h != hlook)
5844 		{
5845 		  struct elf_link_hash_entry *t;
5846 
5847 		  hlook->u.alias = h;
5848 		  hlook->is_weakalias = 1;
5849 		  t = h;
5850 		  if (t->u.alias != NULL)
5851 		    while (t->u.alias != h)
5852 		      t = t->u.alias;
5853 		  t->u.alias = hlook;
5854 
5855 		  /* If the weak definition is in the list of dynamic
5856 		     symbols, make sure the real definition is put
5857 		     there as well.  */
5858 		  if (hlook->dynindx != -1 && h->dynindx == -1)
5859 		    {
5860 		      if (! bfd_elf_link_record_dynamic_symbol (info, h))
5861 			{
5862 			err_free_sym_hash:
5863 			  free (sorted_sym_hash);
5864 			  goto error_return;
5865 			}
5866 		    }
5867 
5868 		  /* If the real definition is in the list of dynamic
5869 		     symbols, make sure the weak definition is put
5870 		     there as well.  If we don't do this, then the
5871 		     dynamic loader might not merge the entries for the
5872 		     real definition and the weak definition.  */
5873 		  if (h->dynindx != -1 && hlook->dynindx == -1)
5874 		    {
5875 		      if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
5876 			goto err_free_sym_hash;
5877 		    }
5878 		  break;
5879 		}
5880 	    }
5881 	}
5882 
5883       free (sorted_sym_hash);
5884     }
5885 
5886   if (bed->check_directives
5887       && !(*bed->check_directives) (abfd, info))
5888     return false;
5889 
5890   /* If this is a non-traditional link, try to optimize the handling
5891      of the .stab/.stabstr sections.  */
5892   if (! dynamic
5893       && ! info->traditional_format
5894       && is_elf_hash_table (&htab->root)
5895       && (info->strip != strip_all && info->strip != strip_debugger))
5896     {
5897       asection *stabstr;
5898 
5899       stabstr = bfd_get_section_by_name (abfd, ".stabstr");
5900       if (stabstr != NULL)
5901 	{
5902 	  bfd_size_type string_offset = 0;
5903 	  asection *stab;
5904 
5905 	  for (stab = abfd->sections; stab; stab = stab->next)
5906 	    if (startswith (stab->name, ".stab")
5907 		&& (!stab->name[5] ||
5908 		    (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
5909 		&& (stab->flags & SEC_MERGE) == 0
5910 		&& !bfd_is_abs_section (stab->output_section))
5911 	      {
5912 		struct bfd_elf_section_data *secdata;
5913 
5914 		secdata = elf_section_data (stab);
5915 		if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
5916 					       stabstr, &secdata->sec_info,
5917 					       &string_offset))
5918 		  goto error_return;
5919 		if (secdata->sec_info)
5920 		  stab->sec_info_type = SEC_INFO_TYPE_STABS;
5921 	    }
5922 	}
5923     }
5924 
5925   if (dynamic && add_needed)
5926     {
5927       /* Add this bfd to the loaded list.  */
5928       struct elf_link_loaded_list *n;
5929 
5930       n = (struct elf_link_loaded_list *) bfd_alloc (abfd, sizeof (*n));
5931       if (n == NULL)
5932 	goto error_return;
5933       n->abfd = abfd;
5934       n->next = htab->dyn_loaded;
5935       htab->dyn_loaded = n;
5936     }
5937   if (dynamic && !add_needed
5938       && (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) != 0)
5939     elf_dyn_lib_class (abfd) |= DYN_NO_NEEDED;
5940 
5941   return true;
5942 
5943  error_free_vers:
5944   free (old_tab);
5945   free (old_strtab);
5946   free (nondeflt_vers);
5947   free (extversym);
5948  error_free_sym:
5949   free (isymbuf);
5950  error_return:
5951   return false;
5952 }
5953 
5954 /* Return the linker hash table entry of a symbol that might be
5955    satisfied by an archive symbol.  Return -1 on error.  */
5956 
5957 struct bfd_link_hash_entry *
_bfd_elf_archive_symbol_lookup(bfd * abfd,struct bfd_link_info * info,const char * name)5958 _bfd_elf_archive_symbol_lookup (bfd *abfd,
5959 				struct bfd_link_info *info,
5960 				const char *name)
5961 {
5962   struct bfd_link_hash_entry *h;
5963   char *p, *copy;
5964   size_t len, first;
5965 
5966   h = bfd_link_hash_lookup (info->hash, name, false, false, true);
5967   if (h != NULL)
5968     return h;
5969 
5970   /* If this is a default version (the name contains @@), look up the
5971      symbol again with only one `@' as well as without the version.
5972      The effect is that references to the symbol with and without the
5973      version will be matched by the default symbol in the archive.  */
5974 
5975   p = strchr (name, ELF_VER_CHR);
5976   if (p == NULL || p[1] != ELF_VER_CHR)
5977     return h;
5978 
5979   /* First check with only one `@'.  */
5980   len = strlen (name);
5981   copy = (char *) bfd_alloc (abfd, len);
5982   if (copy == NULL)
5983     return (struct bfd_link_hash_entry *) -1;
5984 
5985   first = p - name + 1;
5986   memcpy (copy, name, first);
5987   memcpy (copy + first, name + first + 1, len - first);
5988 
5989   h = bfd_link_hash_lookup (info->hash, copy, false, false, true);
5990   if (h == NULL)
5991     {
5992       /* We also need to check references to the symbol without the
5993 	 version.  */
5994       copy[first - 1] = '\0';
5995       h = bfd_link_hash_lookup (info->hash, copy, false, false, true);
5996     }
5997 
5998   bfd_release (abfd, copy);
5999   return h;
6000 }
6001 
6002 /* Add symbols from an ELF archive file to the linker hash table.  We
6003    don't use _bfd_generic_link_add_archive_symbols because we need to
6004    handle versioned symbols.
6005 
6006    Fortunately, ELF archive handling is simpler than that done by
6007    _bfd_generic_link_add_archive_symbols, which has to allow for a.out
6008    oddities.  In ELF, if we find a symbol in the archive map, and the
6009    symbol is currently undefined, we know that we must pull in that
6010    object file.
6011 
6012    Unfortunately, we do have to make multiple passes over the symbol
6013    table until nothing further is resolved.  */
6014 
6015 static bool
elf_link_add_archive_symbols(bfd * abfd,struct bfd_link_info * info)6016 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
6017 {
6018   symindex c;
6019   unsigned char *included = NULL;
6020   carsym *symdefs;
6021   bool loop;
6022   size_t amt;
6023   const struct elf_backend_data *bed;
6024   struct bfd_link_hash_entry * (*archive_symbol_lookup)
6025     (bfd *, struct bfd_link_info *, const char *);
6026 
6027   if (! bfd_has_map (abfd))
6028     {
6029       /* An empty archive is a special case.  */
6030       if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
6031 	return true;
6032       bfd_set_error (bfd_error_no_armap);
6033       return false;
6034     }
6035 
6036   /* Keep track of all symbols we know to be already defined, and all
6037      files we know to be already included.  This is to speed up the
6038      second and subsequent passes.  */
6039   c = bfd_ardata (abfd)->symdef_count;
6040   if (c == 0)
6041     return true;
6042   amt = c * sizeof (*included);
6043   included = (unsigned char *) bfd_zmalloc (amt);
6044   if (included == NULL)
6045     return false;
6046 
6047   symdefs = bfd_ardata (abfd)->symdefs;
6048   bed = get_elf_backend_data (abfd);
6049   archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
6050 
6051   do
6052     {
6053       file_ptr last;
6054       symindex i;
6055       carsym *symdef;
6056       carsym *symdefend;
6057 
6058       loop = false;
6059       last = -1;
6060 
6061       symdef = symdefs;
6062       symdefend = symdef + c;
6063       for (i = 0; symdef < symdefend; symdef++, i++)
6064 	{
6065 	  struct bfd_link_hash_entry *h;
6066 	  bfd *element;
6067 	  struct bfd_link_hash_entry *undefs_tail;
6068 	  symindex mark;
6069 
6070 	  if (included[i])
6071 	    continue;
6072 	  if (symdef->file_offset == last)
6073 	    {
6074 	      included[i] = true;
6075 	      continue;
6076 	    }
6077 
6078 	  h = archive_symbol_lookup (abfd, info, symdef->name);
6079 	  if (h == (struct bfd_link_hash_entry *) -1)
6080 	    goto error_return;
6081 
6082 	  if (h == NULL)
6083 	    continue;
6084 
6085 	  if (h->type == bfd_link_hash_undefined)
6086 	    {
6087 	      /* If the archive element has already been loaded then one
6088 		 of the symbols defined by that element might have been
6089 		 made undefined due to being in a discarded section.  */
6090 	      if (is_elf_hash_table (info->hash)
6091 		  && ((struct elf_link_hash_entry *) h)->indx == -3)
6092 		continue;
6093 	    }
6094 	  else if (h->type == bfd_link_hash_common)
6095 	    {
6096 	      /* We currently have a common symbol.  The archive map contains
6097 		 a reference to this symbol, so we may want to include it.  We
6098 		 only want to include it however, if this archive element
6099 		 contains a definition of the symbol, not just another common
6100 		 declaration of it.
6101 
6102 		 Unfortunately some archivers (including GNU ar) will put
6103 		 declarations of common symbols into their archive maps, as
6104 		 well as real definitions, so we cannot just go by the archive
6105 		 map alone.  Instead we must read in the element's symbol
6106 		 table and check that to see what kind of symbol definition
6107 		 this is.  */
6108 	      if (! elf_link_is_defined_archive_symbol (abfd, symdef))
6109 		continue;
6110 	    }
6111 	  else
6112 	    {
6113 	      if (h->type != bfd_link_hash_undefweak)
6114 		/* Symbol must be defined.  Don't check it again.  */
6115 		included[i] = true;
6116 	      continue;
6117 	    }
6118 
6119 	  /* We need to include this archive member.  */
6120 	  element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset,
6121 					     info);
6122 	  if (element == NULL)
6123 	    goto error_return;
6124 
6125 	  if (! bfd_check_format (element, bfd_object))
6126 	    goto error_return;
6127 
6128 	  undefs_tail = info->hash->undefs_tail;
6129 
6130 	  if (!(*info->callbacks
6131 		->add_archive_element) (info, element, symdef->name, &element))
6132 	    continue;
6133 	  if (!bfd_link_add_symbols (element, info))
6134 	    goto error_return;
6135 
6136 	  /* If there are any new undefined symbols, we need to make
6137 	     another pass through the archive in order to see whether
6138 	     they can be defined.  FIXME: This isn't perfect, because
6139 	     common symbols wind up on undefs_tail and because an
6140 	     undefined symbol which is defined later on in this pass
6141 	     does not require another pass.  This isn't a bug, but it
6142 	     does make the code less efficient than it could be.  */
6143 	  if (undefs_tail != info->hash->undefs_tail)
6144 	    loop = true;
6145 
6146 	  /* Look backward to mark all symbols from this object file
6147 	     which we have already seen in this pass.  */
6148 	  mark = i;
6149 	  do
6150 	    {
6151 	      included[mark] = true;
6152 	      if (mark == 0)
6153 		break;
6154 	      --mark;
6155 	    }
6156 	  while (symdefs[mark].file_offset == symdef->file_offset);
6157 
6158 	  /* We mark subsequent symbols from this object file as we go
6159 	     on through the loop.  */
6160 	  last = symdef->file_offset;
6161 	}
6162     }
6163   while (loop);
6164 
6165   free (included);
6166   return true;
6167 
6168  error_return:
6169   free (included);
6170   return false;
6171 }
6172 
6173 /* Given an ELF BFD, add symbols to the global hash table as
6174    appropriate.  */
6175 
6176 bool
bfd_elf_link_add_symbols(bfd * abfd,struct bfd_link_info * info)6177 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
6178 {
6179   switch (bfd_get_format (abfd))
6180     {
6181     case bfd_object:
6182       return elf_link_add_object_symbols (abfd, info);
6183     case bfd_archive:
6184       return elf_link_add_archive_symbols (abfd, info);
6185     default:
6186       bfd_set_error (bfd_error_wrong_format);
6187       return false;
6188     }
6189 }
6190 
6191 struct hash_codes_info
6192 {
6193   unsigned long *hashcodes;
6194   bool error;
6195 };
6196 
6197 /* This function will be called though elf_link_hash_traverse to store
6198    all hash value of the exported symbols in an array.  */
6199 
6200 static bool
elf_collect_hash_codes(struct elf_link_hash_entry * h,void * data)6201 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
6202 {
6203   struct hash_codes_info *inf = (struct hash_codes_info *) data;
6204   const char *name;
6205   unsigned long ha;
6206   char *alc = NULL;
6207 
6208   /* Ignore indirect symbols.  These are added by the versioning code.  */
6209   if (h->dynindx == -1)
6210     return true;
6211 
6212   name = h->root.root.string;
6213   if (h->versioned >= versioned)
6214     {
6215       char *p = strchr (name, ELF_VER_CHR);
6216       if (p != NULL)
6217 	{
6218 	  alc = (char *) bfd_malloc (p - name + 1);
6219 	  if (alc == NULL)
6220 	    {
6221 	      inf->error = true;
6222 	      return false;
6223 	    }
6224 	  memcpy (alc, name, p - name);
6225 	  alc[p - name] = '\0';
6226 	  name = alc;
6227 	}
6228     }
6229 
6230   /* Compute the hash value.  */
6231   ha = bfd_elf_hash (name);
6232 
6233   /* Store the found hash value in the array given as the argument.  */
6234   *(inf->hashcodes)++ = ha;
6235 
6236   /* And store it in the struct so that we can put it in the hash table
6237      later.  */
6238   h->u.elf_hash_value = ha;
6239 
6240   free (alc);
6241   return true;
6242 }
6243 
6244 struct collect_gnu_hash_codes
6245 {
6246   bfd *output_bfd;
6247   const struct elf_backend_data *bed;
6248   unsigned long int nsyms;
6249   unsigned long int maskbits;
6250   unsigned long int *hashcodes;
6251   unsigned long int *hashval;
6252   unsigned long int *indx;
6253   unsigned long int *counts;
6254   bfd_vma *bitmask;
6255   bfd_byte *contents;
6256   bfd_size_type xlat;
6257   long int min_dynindx;
6258   unsigned long int bucketcount;
6259   unsigned long int symindx;
6260   long int local_indx;
6261   long int shift1, shift2;
6262   unsigned long int mask;
6263   bool error;
6264 };
6265 
6266 /* This function will be called though elf_link_hash_traverse to store
6267    all hash value of the exported symbols in an array.  */
6268 
6269 static bool
elf_collect_gnu_hash_codes(struct elf_link_hash_entry * h,void * data)6270 elf_collect_gnu_hash_codes (struct elf_link_hash_entry *h, void *data)
6271 {
6272   struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
6273   const char *name;
6274   unsigned long ha;
6275   char *alc = NULL;
6276 
6277   /* Ignore indirect symbols.  These are added by the versioning code.  */
6278   if (h->dynindx == -1)
6279     return true;
6280 
6281   /* Ignore also local symbols and undefined symbols.  */
6282   if (! (*s->bed->elf_hash_symbol) (h))
6283     return true;
6284 
6285   name = h->root.root.string;
6286   if (h->versioned >= versioned)
6287     {
6288       char *p = strchr (name, ELF_VER_CHR);
6289       if (p != NULL)
6290 	{
6291 	  alc = (char *) bfd_malloc (p - name + 1);
6292 	  if (alc == NULL)
6293 	    {
6294 	      s->error = true;
6295 	      return false;
6296 	    }
6297 	  memcpy (alc, name, p - name);
6298 	  alc[p - name] = '\0';
6299 	  name = alc;
6300 	}
6301     }
6302 
6303   /* Compute the hash value.  */
6304   ha = bfd_elf_gnu_hash (name);
6305 
6306   /* Store the found hash value in the array for compute_bucket_count,
6307      and also for .dynsym reordering purposes.  */
6308   s->hashcodes[s->nsyms] = ha;
6309   s->hashval[h->dynindx] = ha;
6310   ++s->nsyms;
6311   if (s->min_dynindx < 0 || s->min_dynindx > h->dynindx)
6312     s->min_dynindx = h->dynindx;
6313 
6314   free (alc);
6315   return true;
6316 }
6317 
6318 /* This function will be called though elf_link_hash_traverse to do
6319    final dynamic symbol renumbering in case of .gnu.hash.
6320    If using .MIPS.xhash, invoke record_xhash_symbol to add symbol index
6321    to the translation table.  */
6322 
6323 static bool
elf_gnu_hash_process_symidx(struct elf_link_hash_entry * h,void * data)6324 elf_gnu_hash_process_symidx (struct elf_link_hash_entry *h, void *data)
6325 {
6326   struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
6327   unsigned long int bucket;
6328   unsigned long int val;
6329 
6330   /* Ignore indirect symbols.  */
6331   if (h->dynindx == -1)
6332     return true;
6333 
6334   /* Ignore also local symbols and undefined symbols.  */
6335   if (! (*s->bed->elf_hash_symbol) (h))
6336     {
6337       if (h->dynindx >= s->min_dynindx)
6338 	{
6339 	  if (s->bed->record_xhash_symbol != NULL)
6340 	    {
6341 	      (*s->bed->record_xhash_symbol) (h, 0);
6342 	      s->local_indx++;
6343 	    }
6344 	  else
6345 	    h->dynindx = s->local_indx++;
6346 	}
6347       return true;
6348     }
6349 
6350   bucket = s->hashval[h->dynindx] % s->bucketcount;
6351   val = (s->hashval[h->dynindx] >> s->shift1)
6352 	& ((s->maskbits >> s->shift1) - 1);
6353   s->bitmask[val] |= ((bfd_vma) 1) << (s->hashval[h->dynindx] & s->mask);
6354   s->bitmask[val]
6355     |= ((bfd_vma) 1) << ((s->hashval[h->dynindx] >> s->shift2) & s->mask);
6356   val = s->hashval[h->dynindx] & ~(unsigned long int) 1;
6357   if (s->counts[bucket] == 1)
6358     /* Last element terminates the chain.  */
6359     val |= 1;
6360   bfd_put_32 (s->output_bfd, val,
6361 	      s->contents + (s->indx[bucket] - s->symindx) * 4);
6362   --s->counts[bucket];
6363   if (s->bed->record_xhash_symbol != NULL)
6364     {
6365       bfd_vma xlat_loc = s->xlat + (s->indx[bucket]++ - s->symindx) * 4;
6366 
6367       (*s->bed->record_xhash_symbol) (h, xlat_loc);
6368     }
6369   else
6370     h->dynindx = s->indx[bucket]++;
6371   return true;
6372 }
6373 
6374 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section.  */
6375 
6376 bool
_bfd_elf_hash_symbol(struct elf_link_hash_entry * h)6377 _bfd_elf_hash_symbol (struct elf_link_hash_entry *h)
6378 {
6379   return !(h->forced_local
6380 	   || h->root.type == bfd_link_hash_undefined
6381 	   || h->root.type == bfd_link_hash_undefweak
6382 	   || ((h->root.type == bfd_link_hash_defined
6383 		|| h->root.type == bfd_link_hash_defweak)
6384 	       && h->root.u.def.section->output_section == NULL));
6385 }
6386 
6387 /* Array used to determine the number of hash table buckets to use
6388    based on the number of symbols there are.  If there are fewer than
6389    3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
6390    fewer than 37 we use 17 buckets, and so forth.  We never use more
6391    than 32771 buckets.  */
6392 
6393 static const size_t elf_buckets[] =
6394 {
6395   1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
6396   16411, 32771, 0
6397 };
6398 
6399 /* Compute bucket count for hashing table.  We do not use a static set
6400    of possible tables sizes anymore.  Instead we determine for all
6401    possible reasonable sizes of the table the outcome (i.e., the
6402    number of collisions etc) and choose the best solution.  The
6403    weighting functions are not too simple to allow the table to grow
6404    without bounds.  Instead one of the weighting factors is the size.
6405    Therefore the result is always a good payoff between few collisions
6406    (= short chain lengths) and table size.  */
6407 static size_t
compute_bucket_count(struct bfd_link_info * info ATTRIBUTE_UNUSED,unsigned long int * hashcodes ATTRIBUTE_UNUSED,unsigned long int nsyms,int gnu_hash)6408 compute_bucket_count (struct bfd_link_info *info ATTRIBUTE_UNUSED,
6409 		      unsigned long int *hashcodes ATTRIBUTE_UNUSED,
6410 		      unsigned long int nsyms,
6411 		      int gnu_hash)
6412 {
6413   size_t best_size = 0;
6414   unsigned long int i;
6415 
6416   if (info->optimize)
6417     {
6418       size_t minsize;
6419       size_t maxsize;
6420       uint64_t best_chlen = ~((uint64_t) 0);
6421       bfd *dynobj = elf_hash_table (info)->dynobj;
6422       size_t dynsymcount = elf_hash_table (info)->dynsymcount;
6423       const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
6424       unsigned long int *counts;
6425       bfd_size_type amt;
6426       unsigned int no_improvement_count = 0;
6427 
6428       /* Possible optimization parameters: if we have NSYMS symbols we say
6429 	 that the hashing table must at least have NSYMS/4 and at most
6430 	 2*NSYMS buckets.  */
6431       minsize = nsyms / 4;
6432       if (minsize == 0)
6433 	minsize = 1;
6434       best_size = maxsize = nsyms * 2;
6435       if (gnu_hash)
6436 	{
6437 	  if (minsize < 2)
6438 	    minsize = 2;
6439 	  if ((best_size & 31) == 0)
6440 	    ++best_size;
6441 	}
6442 
6443       /* Create array where we count the collisions in.  We must use bfd_malloc
6444 	 since the size could be large.  */
6445       amt = maxsize;
6446       amt *= sizeof (unsigned long int);
6447       counts = (unsigned long int *) bfd_malloc (amt);
6448       if (counts == NULL)
6449 	return 0;
6450 
6451       /* Compute the "optimal" size for the hash table.  The criteria is a
6452 	 minimal chain length.  The minor criteria is (of course) the size
6453 	 of the table.  */
6454       for (i = minsize; i < maxsize; ++i)
6455 	{
6456 	  /* Walk through the array of hashcodes and count the collisions.  */
6457 	  uint64_t max;
6458 	  unsigned long int j;
6459 	  unsigned long int fact;
6460 
6461 	  if (gnu_hash && (i & 31) == 0)
6462 	    continue;
6463 
6464 	  memset (counts, '\0', i * sizeof (unsigned long int));
6465 
6466 	  /* Determine how often each hash bucket is used.  */
6467 	  for (j = 0; j < nsyms; ++j)
6468 	    ++counts[hashcodes[j] % i];
6469 
6470 	  /* For the weight function we need some information about the
6471 	     pagesize on the target.  This is information need not be 100%
6472 	     accurate.  Since this information is not available (so far) we
6473 	     define it here to a reasonable default value.  If it is crucial
6474 	     to have a better value some day simply define this value.  */
6475 # ifndef BFD_TARGET_PAGESIZE
6476 #  define BFD_TARGET_PAGESIZE	(4096)
6477 # endif
6478 
6479 	  /* We in any case need 2 + DYNSYMCOUNT entries for the size values
6480 	     and the chains.  */
6481 	  max = (2 + dynsymcount) * bed->s->sizeof_hash_entry;
6482 
6483 # if 1
6484 	  /* Variant 1: optimize for short chains.  We add the squares
6485 	     of all the chain lengths (which favors many small chain
6486 	     over a few long chains).  */
6487 	  for (j = 0; j < i; ++j)
6488 	    max += counts[j] * counts[j];
6489 
6490 	  /* This adds penalties for the overall size of the table.  */
6491 	  fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
6492 	  max *= fact * fact;
6493 # else
6494 	  /* Variant 2: Optimize a lot more for small table.  Here we
6495 	     also add squares of the size but we also add penalties for
6496 	     empty slots (the +1 term).  */
6497 	  for (j = 0; j < i; ++j)
6498 	    max += (1 + counts[j]) * (1 + counts[j]);
6499 
6500 	  /* The overall size of the table is considered, but not as
6501 	     strong as in variant 1, where it is squared.  */
6502 	  fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
6503 	  max *= fact;
6504 # endif
6505 
6506 	  /* Compare with current best results.  */
6507 	  if (max < best_chlen)
6508 	    {
6509 	      best_chlen = max;
6510 	      best_size = i;
6511 	      no_improvement_count = 0;
6512 	    }
6513 	  /* PR 11843: Avoid futile long searches for the best bucket size
6514 	     when there are a large number of symbols.  */
6515 	  else if (++no_improvement_count == 100)
6516 	    break;
6517 	}
6518 
6519       free (counts);
6520     }
6521   else
6522     {
6523       for (i = 0; elf_buckets[i] != 0; i++)
6524 	{
6525 	  best_size = elf_buckets[i];
6526 	  if (nsyms < elf_buckets[i + 1])
6527 	    break;
6528 	}
6529       if (gnu_hash && best_size < 2)
6530 	best_size = 2;
6531     }
6532 
6533   return best_size;
6534 }
6535 
6536 /* Size any SHT_GROUP section for ld -r.  */
6537 
6538 bool
_bfd_elf_size_group_sections(struct bfd_link_info * info)6539 _bfd_elf_size_group_sections (struct bfd_link_info *info)
6540 {
6541   bfd *ibfd;
6542   asection *s;
6543 
6544   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
6545     if (bfd_get_flavour (ibfd) == bfd_target_elf_flavour
6546 	&& (s = ibfd->sections) != NULL
6547 	&& s->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
6548 	&& !_bfd_elf_fixup_group_sections (ibfd, bfd_abs_section_ptr))
6549       return false;
6550   return true;
6551 }
6552 
6553 /* Set a default stack segment size.  The value in INFO wins.  If it
6554    is unset, LEGACY_SYMBOL's value is used, and if that symbol is
6555    undefined it is initialized.  */
6556 
6557 bool
bfd_elf_stack_segment_size(bfd * output_bfd,struct bfd_link_info * info,const char * legacy_symbol,bfd_vma default_size)6558 bfd_elf_stack_segment_size (bfd *output_bfd,
6559 			    struct bfd_link_info *info,
6560 			    const char *legacy_symbol,
6561 			    bfd_vma default_size)
6562 {
6563   struct elf_link_hash_entry *h = NULL;
6564 
6565   /* Look for legacy symbol.  */
6566   if (legacy_symbol)
6567     h = elf_link_hash_lookup (elf_hash_table (info), legacy_symbol,
6568 			      false, false, false);
6569   if (h && (h->root.type == bfd_link_hash_defined
6570 	    || h->root.type == bfd_link_hash_defweak)
6571       && h->def_regular
6572       && (h->type == STT_NOTYPE || h->type == STT_OBJECT))
6573     {
6574       /* The symbol has no type if specified on the command line.  */
6575       h->type = STT_OBJECT;
6576       if (info->stacksize)
6577 	/* xgettext:c-format */
6578 	_bfd_error_handler (_("%pB: stack size specified and %s set"),
6579 			    output_bfd, legacy_symbol);
6580       else if (h->root.u.def.section != bfd_abs_section_ptr)
6581 	/* xgettext:c-format */
6582 	_bfd_error_handler (_("%pB: %s not absolute"),
6583 			    output_bfd, legacy_symbol);
6584       else
6585 	info->stacksize = h->root.u.def.value;
6586     }
6587 
6588   if (!info->stacksize)
6589     /* If the user didn't set a size, or explicitly inhibit the
6590        size, set it now.  */
6591     info->stacksize = default_size;
6592 
6593   /* Provide the legacy symbol, if it is referenced.  */
6594   if (h && (h->root.type == bfd_link_hash_undefined
6595 	    || h->root.type == bfd_link_hash_undefweak))
6596     {
6597       struct bfd_link_hash_entry *bh = NULL;
6598 
6599       if (!(_bfd_generic_link_add_one_symbol
6600 	    (info, output_bfd, legacy_symbol,
6601 	     BSF_GLOBAL, bfd_abs_section_ptr,
6602 	     info->stacksize >= 0 ? info->stacksize : 0,
6603 	     NULL, false, get_elf_backend_data (output_bfd)->collect, &bh)))
6604 	return false;
6605 
6606       h = (struct elf_link_hash_entry *) bh;
6607       h->def_regular = 1;
6608       h->type = STT_OBJECT;
6609     }
6610 
6611   return true;
6612 }
6613 
6614 /* Sweep symbols in swept sections.  Called via elf_link_hash_traverse.  */
6615 
6616 struct elf_gc_sweep_symbol_info
6617 {
6618   struct bfd_link_info *info;
6619   void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
6620 		       bool);
6621 };
6622 
6623 static bool
elf_gc_sweep_symbol(struct elf_link_hash_entry * h,void * data)6624 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
6625 {
6626   if (!h->mark
6627       && (((h->root.type == bfd_link_hash_defined
6628 	    || h->root.type == bfd_link_hash_defweak)
6629 	   && !((h->def_regular || ELF_COMMON_DEF_P (h))
6630 		&& h->root.u.def.section->gc_mark))
6631 	  || h->root.type == bfd_link_hash_undefined
6632 	  || h->root.type == bfd_link_hash_undefweak))
6633     {
6634       struct elf_gc_sweep_symbol_info *inf;
6635 
6636       inf = (struct elf_gc_sweep_symbol_info *) data;
6637       (*inf->hide_symbol) (inf->info, h, true);
6638       h->def_regular = 0;
6639       h->ref_regular = 0;
6640       h->ref_regular_nonweak = 0;
6641     }
6642 
6643   return true;
6644 }
6645 
6646 /* Set up the sizes and contents of the ELF dynamic sections.  This is
6647    called by the ELF linker emulation before_allocation routine.  We
6648    must set the sizes of the sections before the linker sets the
6649    addresses of the various sections.  */
6650 
6651 bool
bfd_elf_size_dynamic_sections(bfd * output_bfd,const char * soname,const char * rpath,const char * filter_shlib,const char * audit,const char * depaudit,const char * const * auxiliary_filters,struct bfd_link_info * info,asection ** sinterpptr)6652 bfd_elf_size_dynamic_sections (bfd *output_bfd,
6653 			       const char *soname,
6654 			       const char *rpath,
6655 			       const char *filter_shlib,
6656 			       const char *audit,
6657 			       const char *depaudit,
6658 			       const char * const *auxiliary_filters,
6659 			       struct bfd_link_info *info,
6660 			       asection **sinterpptr)
6661 {
6662   bfd *dynobj;
6663   const struct elf_backend_data *bed;
6664 
6665   *sinterpptr = NULL;
6666 
6667   if (!is_elf_hash_table (info->hash))
6668     return true;
6669 
6670   /* Any syms created from now on start with -1 in
6671      got.refcount/offset and plt.refcount/offset.  */
6672   elf_hash_table (info)->init_got_refcount
6673     = elf_hash_table (info)->init_got_offset;
6674   elf_hash_table (info)->init_plt_refcount
6675     = elf_hash_table (info)->init_plt_offset;
6676 
6677   bed = get_elf_backend_data (output_bfd);
6678 
6679   /* The backend may have to create some sections regardless of whether
6680      we're dynamic or not.  */
6681   if (bed->elf_backend_always_size_sections
6682       && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
6683     return false;
6684 
6685   dynobj = elf_hash_table (info)->dynobj;
6686 
6687   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
6688     {
6689       struct bfd_elf_version_tree *verdefs;
6690       struct elf_info_failed asvinfo;
6691       struct bfd_elf_version_tree *t;
6692       struct bfd_elf_version_expr *d;
6693       asection *s;
6694       size_t soname_indx;
6695 
6696       /* If we are supposed to export all symbols into the dynamic symbol
6697 	 table (this is not the normal case), then do so.  */
6698       if (info->export_dynamic
6699 	  || (bfd_link_executable (info) && info->dynamic))
6700 	{
6701 	  struct elf_info_failed eif;
6702 
6703 	  eif.info = info;
6704 	  eif.failed = false;
6705 	  elf_link_hash_traverse (elf_hash_table (info),
6706 				  _bfd_elf_export_symbol,
6707 				  &eif);
6708 	  if (eif.failed)
6709 	    return false;
6710 	}
6711 
6712       if (soname != NULL)
6713 	{
6714 	  soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6715 					     soname, true);
6716 	  if (soname_indx == (size_t) -1
6717 	      || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
6718 	    return false;
6719 	}
6720       else
6721 	soname_indx = (size_t) -1;
6722 
6723       /* Make all global versions with definition.  */
6724       for (t = info->version_info; t != NULL; t = t->next)
6725 	for (d = t->globals.list; d != NULL; d = d->next)
6726 	  if (!d->symver && d->literal)
6727 	    {
6728 	      const char *verstr, *name;
6729 	      size_t namelen, verlen, newlen;
6730 	      char *newname, *p, leading_char;
6731 	      struct elf_link_hash_entry *newh;
6732 
6733 	      leading_char = bfd_get_symbol_leading_char (output_bfd);
6734 	      name = d->pattern;
6735 	      namelen = strlen (name) + (leading_char != '\0');
6736 	      verstr = t->name;
6737 	      verlen = strlen (verstr);
6738 	      newlen = namelen + verlen + 3;
6739 
6740 	      newname = (char *) bfd_malloc (newlen);
6741 	      if (newname == NULL)
6742 		return false;
6743 	      newname[0] = leading_char;
6744 	      memcpy (newname + (leading_char != '\0'), name, namelen);
6745 
6746 	      /* Check the hidden versioned definition.  */
6747 	      p = newname + namelen;
6748 	      *p++ = ELF_VER_CHR;
6749 	      memcpy (p, verstr, verlen + 1);
6750 	      newh = elf_link_hash_lookup (elf_hash_table (info),
6751 					   newname, false, false,
6752 					   false);
6753 	      if (newh == NULL
6754 		  || (newh->root.type != bfd_link_hash_defined
6755 		      && newh->root.type != bfd_link_hash_defweak))
6756 		{
6757 		  /* Check the default versioned definition.  */
6758 		  *p++ = ELF_VER_CHR;
6759 		  memcpy (p, verstr, verlen + 1);
6760 		  newh = elf_link_hash_lookup (elf_hash_table (info),
6761 					       newname, false, false,
6762 					       false);
6763 		}
6764 	      free (newname);
6765 
6766 	      /* Mark this version if there is a definition and it is
6767 		 not defined in a shared object.  */
6768 	      if (newh != NULL
6769 		  && !newh->def_dynamic
6770 		  && (newh->root.type == bfd_link_hash_defined
6771 		      || newh->root.type == bfd_link_hash_defweak))
6772 		d->symver = 1;
6773 	    }
6774 
6775       /* Attach all the symbols to their version information.  */
6776       asvinfo.info = info;
6777       asvinfo.failed = false;
6778 
6779       elf_link_hash_traverse (elf_hash_table (info),
6780 			      _bfd_elf_link_assign_sym_version,
6781 			      &asvinfo);
6782       if (asvinfo.failed)
6783 	return false;
6784 
6785       if (!info->allow_undefined_version)
6786 	{
6787 	  /* Check if all global versions have a definition.  */
6788 	  bool all_defined = true;
6789 	  for (t = info->version_info; t != NULL; t = t->next)
6790 	    for (d = t->globals.list; d != NULL; d = d->next)
6791 	      if (d->literal && !d->symver && !d->script)
6792 		{
6793 		  _bfd_error_handler
6794 		    (_("%s: undefined version: %s"),
6795 		     d->pattern, t->name);
6796 		  all_defined = false;
6797 		}
6798 
6799 	  if (!all_defined)
6800 	    {
6801 	      bfd_set_error (bfd_error_bad_value);
6802 	      return false;
6803 	    }
6804 	}
6805 
6806       /* Set up the version definition section.  */
6807       s = bfd_get_linker_section (dynobj, ".gnu.version_d");
6808       BFD_ASSERT (s != NULL);
6809 
6810       /* We may have created additional version definitions if we are
6811 	 just linking a regular application.  */
6812       verdefs = info->version_info;
6813 
6814       /* Skip anonymous version tag.  */
6815       if (verdefs != NULL && verdefs->vernum == 0)
6816 	verdefs = verdefs->next;
6817 
6818       if (verdefs == NULL && !info->create_default_symver)
6819 	s->flags |= SEC_EXCLUDE;
6820       else
6821 	{
6822 	  unsigned int cdefs;
6823 	  bfd_size_type size;
6824 	  bfd_byte *p;
6825 	  Elf_Internal_Verdef def;
6826 	  Elf_Internal_Verdaux defaux;
6827 	  struct bfd_link_hash_entry *bh;
6828 	  struct elf_link_hash_entry *h;
6829 	  const char *name;
6830 
6831 	  cdefs = 0;
6832 	  size = 0;
6833 
6834 	  /* Make space for the base version.  */
6835 	  size += sizeof (Elf_External_Verdef);
6836 	  size += sizeof (Elf_External_Verdaux);
6837 	  ++cdefs;
6838 
6839 	  /* Make space for the default version.  */
6840 	  if (info->create_default_symver)
6841 	    {
6842 	      size += sizeof (Elf_External_Verdef);
6843 	      ++cdefs;
6844 	    }
6845 
6846 	  for (t = verdefs; t != NULL; t = t->next)
6847 	    {
6848 	      struct bfd_elf_version_deps *n;
6849 
6850 	      /* Don't emit base version twice.  */
6851 	      if (t->vernum == 0)
6852 		continue;
6853 
6854 	      size += sizeof (Elf_External_Verdef);
6855 	      size += sizeof (Elf_External_Verdaux);
6856 	      ++cdefs;
6857 
6858 	      for (n = t->deps; n != NULL; n = n->next)
6859 		size += sizeof (Elf_External_Verdaux);
6860 	    }
6861 
6862 	  s->size = size;
6863 	  s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
6864 	  if (s->contents == NULL && s->size != 0)
6865 	    return false;
6866 
6867 	  /* Fill in the version definition section.  */
6868 
6869 	  p = s->contents;
6870 
6871 	  def.vd_version = VER_DEF_CURRENT;
6872 	  def.vd_flags = VER_FLG_BASE;
6873 	  def.vd_ndx = 1;
6874 	  def.vd_cnt = 1;
6875 	  if (info->create_default_symver)
6876 	    {
6877 	      def.vd_aux = 2 * sizeof (Elf_External_Verdef);
6878 	      def.vd_next = sizeof (Elf_External_Verdef);
6879 	    }
6880 	  else
6881 	    {
6882 	      def.vd_aux = sizeof (Elf_External_Verdef);
6883 	      def.vd_next = (sizeof (Elf_External_Verdef)
6884 			     + sizeof (Elf_External_Verdaux));
6885 	    }
6886 
6887 	  if (soname_indx != (size_t) -1)
6888 	    {
6889 	      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6890 				      soname_indx);
6891 	      def.vd_hash = bfd_elf_hash (soname);
6892 	      defaux.vda_name = soname_indx;
6893 	      name = soname;
6894 	    }
6895 	  else
6896 	    {
6897 	      size_t indx;
6898 
6899 	      name = lbasename (bfd_get_filename (output_bfd));
6900 	      def.vd_hash = bfd_elf_hash (name);
6901 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6902 					  name, false);
6903 	      if (indx == (size_t) -1)
6904 		return false;
6905 	      defaux.vda_name = indx;
6906 	    }
6907 	  defaux.vda_next = 0;
6908 
6909 	  _bfd_elf_swap_verdef_out (output_bfd, &def,
6910 				    (Elf_External_Verdef *) p);
6911 	  p += sizeof (Elf_External_Verdef);
6912 	  if (info->create_default_symver)
6913 	    {
6914 	      /* Add a symbol representing this version.  */
6915 	      bh = NULL;
6916 	      if (! (_bfd_generic_link_add_one_symbol
6917 		     (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
6918 		      0, NULL, false,
6919 		      get_elf_backend_data (dynobj)->collect, &bh)))
6920 		return false;
6921 	      h = (struct elf_link_hash_entry *) bh;
6922 	      h->non_elf = 0;
6923 	      h->def_regular = 1;
6924 	      h->type = STT_OBJECT;
6925 	      h->verinfo.vertree = NULL;
6926 
6927 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
6928 		return false;
6929 
6930 	      /* Create a duplicate of the base version with the same
6931 		 aux block, but different flags.  */
6932 	      def.vd_flags = 0;
6933 	      def.vd_ndx = 2;
6934 	      def.vd_aux = sizeof (Elf_External_Verdef);
6935 	      if (verdefs)
6936 		def.vd_next = (sizeof (Elf_External_Verdef)
6937 			       + sizeof (Elf_External_Verdaux));
6938 	      else
6939 		def.vd_next = 0;
6940 	      _bfd_elf_swap_verdef_out (output_bfd, &def,
6941 					(Elf_External_Verdef *) p);
6942 	      p += sizeof (Elf_External_Verdef);
6943 	    }
6944 	  _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6945 				     (Elf_External_Verdaux *) p);
6946 	  p += sizeof (Elf_External_Verdaux);
6947 
6948 	  for (t = verdefs; t != NULL; t = t->next)
6949 	    {
6950 	      unsigned int cdeps;
6951 	      struct bfd_elf_version_deps *n;
6952 
6953 	      /* Don't emit the base version twice.  */
6954 	      if (t->vernum == 0)
6955 		continue;
6956 
6957 	      cdeps = 0;
6958 	      for (n = t->deps; n != NULL; n = n->next)
6959 		++cdeps;
6960 
6961 	      /* Add a symbol representing this version.  */
6962 	      bh = NULL;
6963 	      if (! (_bfd_generic_link_add_one_symbol
6964 		     (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
6965 		      0, NULL, false,
6966 		      get_elf_backend_data (dynobj)->collect, &bh)))
6967 		return false;
6968 	      h = (struct elf_link_hash_entry *) bh;
6969 	      h->non_elf = 0;
6970 	      h->def_regular = 1;
6971 	      h->type = STT_OBJECT;
6972 	      h->verinfo.vertree = t;
6973 
6974 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
6975 		return false;
6976 
6977 	      def.vd_version = VER_DEF_CURRENT;
6978 	      def.vd_flags = 0;
6979 	      if (t->globals.list == NULL
6980 		  && t->locals.list == NULL
6981 		  && ! t->used)
6982 		def.vd_flags |= VER_FLG_WEAK;
6983 	      def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
6984 	      def.vd_cnt = cdeps + 1;
6985 	      def.vd_hash = bfd_elf_hash (t->name);
6986 	      def.vd_aux = sizeof (Elf_External_Verdef);
6987 	      def.vd_next = 0;
6988 
6989 	      /* If a basever node is next, it *must* be the last node in
6990 		 the chain, otherwise Verdef construction breaks.  */
6991 	      if (t->next != NULL && t->next->vernum == 0)
6992 		BFD_ASSERT (t->next->next == NULL);
6993 
6994 	      if (t->next != NULL && t->next->vernum != 0)
6995 		def.vd_next = (sizeof (Elf_External_Verdef)
6996 			       + (cdeps + 1) * sizeof (Elf_External_Verdaux));
6997 
6998 	      _bfd_elf_swap_verdef_out (output_bfd, &def,
6999 					(Elf_External_Verdef *) p);
7000 	      p += sizeof (Elf_External_Verdef);
7001 
7002 	      defaux.vda_name = h->dynstr_index;
7003 	      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
7004 				      h->dynstr_index);
7005 	      defaux.vda_next = 0;
7006 	      if (t->deps != NULL)
7007 		defaux.vda_next = sizeof (Elf_External_Verdaux);
7008 	      t->name_indx = defaux.vda_name;
7009 
7010 	      _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
7011 					 (Elf_External_Verdaux *) p);
7012 	      p += sizeof (Elf_External_Verdaux);
7013 
7014 	      for (n = t->deps; n != NULL; n = n->next)
7015 		{
7016 		  if (n->version_needed == NULL)
7017 		    {
7018 		      /* This can happen if there was an error in the
7019 			 version script.  */
7020 		      defaux.vda_name = 0;
7021 		    }
7022 		  else
7023 		    {
7024 		      defaux.vda_name = n->version_needed->name_indx;
7025 		      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
7026 					      defaux.vda_name);
7027 		    }
7028 		  if (n->next == NULL)
7029 		    defaux.vda_next = 0;
7030 		  else
7031 		    defaux.vda_next = sizeof (Elf_External_Verdaux);
7032 
7033 		  _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
7034 					     (Elf_External_Verdaux *) p);
7035 		  p += sizeof (Elf_External_Verdaux);
7036 		}
7037 	    }
7038 
7039 	  elf_tdata (output_bfd)->cverdefs = cdefs;
7040 	}
7041     }
7042 
7043   if (info->gc_sections && bed->can_gc_sections)
7044     {
7045       struct elf_gc_sweep_symbol_info sweep_info;
7046 
7047       /* Remove the symbols that were in the swept sections from the
7048 	 dynamic symbol table.  */
7049       sweep_info.info = info;
7050       sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
7051       elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
7052 			      &sweep_info);
7053     }
7054 
7055   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
7056     {
7057       asection *s;
7058       struct elf_find_verdep_info sinfo;
7059 
7060       /* Work out the size of the version reference section.  */
7061 
7062       s = bfd_get_linker_section (dynobj, ".gnu.version_r");
7063       BFD_ASSERT (s != NULL);
7064 
7065       sinfo.info = info;
7066       sinfo.vers = elf_tdata (output_bfd)->cverdefs;
7067       if (sinfo.vers == 0)
7068 	sinfo.vers = 1;
7069       sinfo.failed = false;
7070 
7071       elf_link_hash_traverse (elf_hash_table (info),
7072 			      _bfd_elf_link_find_version_dependencies,
7073 			      &sinfo);
7074       if (sinfo.failed)
7075 	return false;
7076 
7077       bed->elf_backend_add_glibc_version_dependency (&sinfo);
7078       if (sinfo.failed)
7079 	return false;
7080 
7081       if (elf_tdata (output_bfd)->verref == NULL)
7082 	s->flags |= SEC_EXCLUDE;
7083       else
7084 	{
7085 	  Elf_Internal_Verneed *vn;
7086 	  unsigned int size;
7087 	  unsigned int crefs;
7088 	  bfd_byte *p;
7089 
7090 	  /* Build the version dependency section.  */
7091 	  size = 0;
7092 	  crefs = 0;
7093 	  for (vn = elf_tdata (output_bfd)->verref;
7094 	       vn != NULL;
7095 	       vn = vn->vn_nextref)
7096 	    {
7097 	      Elf_Internal_Vernaux *a;
7098 
7099 	      size += sizeof (Elf_External_Verneed);
7100 	      ++crefs;
7101 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
7102 		size += sizeof (Elf_External_Vernaux);
7103 	    }
7104 
7105 	  s->size = size;
7106 	  s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
7107 	  if (s->contents == NULL)
7108 	    return false;
7109 
7110 	  p = s->contents;
7111 	  for (vn = elf_tdata (output_bfd)->verref;
7112 	       vn != NULL;
7113 	       vn = vn->vn_nextref)
7114 	    {
7115 	      unsigned int caux;
7116 	      Elf_Internal_Vernaux *a;
7117 	      size_t indx;
7118 
7119 	      caux = 0;
7120 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
7121 		++caux;
7122 
7123 	      vn->vn_version = VER_NEED_CURRENT;
7124 	      vn->vn_cnt = caux;
7125 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7126 					  elf_dt_name (vn->vn_bfd) != NULL
7127 					  ? elf_dt_name (vn->vn_bfd)
7128 					  : lbasename (bfd_get_filename
7129 						       (vn->vn_bfd)),
7130 					  false);
7131 	      if (indx == (size_t) -1)
7132 		return false;
7133 	      vn->vn_file = indx;
7134 	      vn->vn_aux = sizeof (Elf_External_Verneed);
7135 	      if (vn->vn_nextref == NULL)
7136 		vn->vn_next = 0;
7137 	      else
7138 		vn->vn_next = (sizeof (Elf_External_Verneed)
7139 			       + caux * sizeof (Elf_External_Vernaux));
7140 
7141 	      _bfd_elf_swap_verneed_out (output_bfd, vn,
7142 					 (Elf_External_Verneed *) p);
7143 	      p += sizeof (Elf_External_Verneed);
7144 
7145 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
7146 		{
7147 		  a->vna_hash = bfd_elf_hash (a->vna_nodename);
7148 		  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7149 					      a->vna_nodename, false);
7150 		  if (indx == (size_t) -1)
7151 		    return false;
7152 		  a->vna_name = indx;
7153 		  if (a->vna_nextptr == NULL)
7154 		    a->vna_next = 0;
7155 		  else
7156 		    a->vna_next = sizeof (Elf_External_Vernaux);
7157 
7158 		  _bfd_elf_swap_vernaux_out (output_bfd, a,
7159 					     (Elf_External_Vernaux *) p);
7160 		  p += sizeof (Elf_External_Vernaux);
7161 		}
7162 	    }
7163 
7164 	  elf_tdata (output_bfd)->cverrefs = crefs;
7165 	}
7166     }
7167 
7168   if (bfd_link_relocatable (info)
7169       && !_bfd_elf_size_group_sections (info))
7170     return false;
7171 
7172   /* Determine any GNU_STACK segment requirements, after the backend
7173      has had a chance to set a default segment size.  */
7174   if (info->execstack)
7175     {
7176       /* If the user has explicitly requested warnings, then generate one even
7177 	 though the choice is the result of another command line option.  */
7178       if (info->warn_execstack == 1)
7179 	{
7180 	  if (info->error_execstack)
7181 	    {
7182 	      _bfd_error_handler
7183 		(_("\
7184 error: creating an executable stack because of -z execstack command line option"));
7185 	      return false;
7186 	    }
7187 
7188 	  _bfd_error_handler
7189 	    (_("\
7190 warning: enabling an executable stack because of -z execstack command line option"));
7191 	}
7192 
7193       elf_stack_flags (output_bfd) = PF_R | PF_W | PF_X;
7194     }
7195   else if (info->noexecstack)
7196     elf_stack_flags (output_bfd) = PF_R | PF_W;
7197   else
7198     {
7199       bfd *inputobj;
7200       asection *notesec = NULL;
7201       bfd *noteobj = NULL;
7202       bfd *emptyobj = NULL;
7203       int exec = 0;
7204 
7205       for (inputobj = info->input_bfds;
7206 	   inputobj;
7207 	   inputobj = inputobj->link.next)
7208 	{
7209 	  asection *s;
7210 
7211 	  if (inputobj->flags
7212 	      & (DYNAMIC | EXEC_P | BFD_PLUGIN | BFD_LINKER_CREATED))
7213 	    continue;
7214 	  s = inputobj->sections;
7215 	  if (s == NULL || s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
7216 	    continue;
7217 
7218 	  s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
7219 	  if (s)
7220 	    {
7221 	      notesec = s;
7222 	      if (s->flags & SEC_CODE)
7223 		{
7224 		  noteobj = inputobj;
7225 		  exec = PF_X;
7226 		  /* There is no point in scanning the remaining bfds.  */
7227 		  break;
7228 		}
7229 	    }
7230 	  else if (bed->default_execstack && info->default_execstack)
7231 	    {
7232 	      exec = PF_X;
7233 	      emptyobj = inputobj;
7234 	    }
7235 	}
7236 
7237       if (notesec || info->stacksize > 0)
7238 	{
7239 	  if (exec)
7240 	    {
7241 	      if (info->warn_execstack != 0)
7242 		{
7243 		  /* PR 29072: Because an executable stack is a serious
7244 		     security risk, make sure that the user knows that it is
7245 		     being enabled despite the fact that it was not requested
7246 		     on the command line.  */
7247 		  if (noteobj)
7248 		    {
7249 		      if (info->error_execstack)
7250 			{
7251 			  _bfd_error_handler (_("\
7252 error: %s: is triggering the generation of an executable stack (because it has an executable .note.GNU-stack section)"),
7253 					      bfd_get_filename (noteobj));
7254 			  return false;
7255 			}
7256 
7257 		      _bfd_error_handler (_("\
7258 warning: %s: requires executable stack (because the .note.GNU-stack section is executable)"),
7259 		       bfd_get_filename (noteobj));
7260 		    }
7261 		  else if (emptyobj)
7262 		    {
7263 		      if (info->error_execstack)
7264 			{
7265 			  _bfd_error_handler (_("\
7266 error: %s: is triggering the generation of an executable stack because it does not have a .note.GNU-stack section"),
7267 					      bfd_get_filename (emptyobj));
7268 			  return false;
7269 			}
7270 
7271 		      _bfd_error_handler (_("\
7272 warning: %s: missing .note.GNU-stack section implies executable stack"),
7273 					  bfd_get_filename (emptyobj));
7274 		      _bfd_error_handler (_("\
7275 NOTE: This behaviour is deprecated and will be removed in a future version of the linker"));
7276 		    }
7277 		}
7278 	    }
7279 	  elf_stack_flags (output_bfd) = PF_R | PF_W | exec;
7280 	}
7281 
7282       if (notesec && exec && bfd_link_relocatable (info)
7283 	  && notesec->output_section != bfd_abs_section_ptr)
7284 	notesec->output_section->flags |= SEC_CODE;
7285     }
7286 
7287   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
7288     {
7289       struct elf_info_failed eif;
7290       struct elf_link_hash_entry *h;
7291       asection *dynstr;
7292       asection *s;
7293 
7294       *sinterpptr = bfd_get_linker_section (dynobj, ".interp");
7295       BFD_ASSERT (*sinterpptr != NULL || !bfd_link_executable (info) || info->nointerp);
7296 
7297       if (info->symbolic)
7298 	{
7299 	  if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
7300 	    return false;
7301 	  info->flags |= DF_SYMBOLIC;
7302 	}
7303 
7304       if (rpath != NULL)
7305 	{
7306 	  size_t indx;
7307 	  bfd_vma tag;
7308 
7309 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
7310 				      true);
7311 	  if (indx == (size_t) -1)
7312 	    return false;
7313 
7314 	  tag = info->new_dtags ? DT_RUNPATH : DT_RPATH;
7315 	  if (!_bfd_elf_add_dynamic_entry (info, tag, indx))
7316 	    return false;
7317 	}
7318 
7319       if (filter_shlib != NULL)
7320 	{
7321 	  size_t indx;
7322 
7323 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7324 				      filter_shlib, true);
7325 	  if (indx == (size_t) -1
7326 	      || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
7327 	    return false;
7328 	}
7329 
7330       if (auxiliary_filters != NULL)
7331 	{
7332 	  const char * const *p;
7333 
7334 	  for (p = auxiliary_filters; *p != NULL; p++)
7335 	    {
7336 	      size_t indx;
7337 
7338 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7339 					  *p, true);
7340 	      if (indx == (size_t) -1
7341 		  || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
7342 		return false;
7343 	    }
7344 	}
7345 
7346       if (audit != NULL)
7347 	{
7348 	  size_t indx;
7349 
7350 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
7351 				      true);
7352 	  if (indx == (size_t) -1
7353 	      || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
7354 	    return false;
7355 	}
7356 
7357       if (depaudit != NULL)
7358 	{
7359 	  size_t indx;
7360 
7361 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
7362 				      true);
7363 	  if (indx == (size_t) -1
7364 	      || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
7365 	    return false;
7366 	}
7367 
7368       eif.info = info;
7369       eif.failed = false;
7370 
7371       /* Find all symbols which were defined in a dynamic object and make
7372 	 the backend pick a reasonable value for them.  */
7373       elf_link_hash_traverse (elf_hash_table (info),
7374 			      _bfd_elf_adjust_dynamic_symbol,
7375 			      &eif);
7376       if (eif.failed)
7377 	return false;
7378 
7379       /* Add some entries to the .dynamic section.  We fill in some of the
7380 	 values later, in bfd_elf_final_link, but we must add the entries
7381 	 now so that we know the final size of the .dynamic section.  */
7382 
7383       /* If there are initialization and/or finalization functions to
7384 	 call then add the corresponding DT_INIT/DT_FINI entries.  */
7385       h = (info->init_function
7386 	   ? elf_link_hash_lookup (elf_hash_table (info),
7387 				   info->init_function, false,
7388 				   false, false)
7389 	   : NULL);
7390       if (h != NULL
7391 	  && (h->ref_regular
7392 	      || h->def_regular))
7393 	{
7394 	  if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
7395 	    return false;
7396 	}
7397       h = (info->fini_function
7398 	   ? elf_link_hash_lookup (elf_hash_table (info),
7399 				   info->fini_function, false,
7400 				   false, false)
7401 	   : NULL);
7402       if (h != NULL
7403 	  && (h->ref_regular
7404 	      || h->def_regular))
7405 	{
7406 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
7407 	    return false;
7408 	}
7409 
7410       s = bfd_get_section_by_name (output_bfd, ".preinit_array");
7411       if (s != NULL && s->linker_has_input)
7412 	{
7413 	  /* DT_PREINIT_ARRAY is not allowed in shared library.  */
7414 	  if (! bfd_link_executable (info))
7415 	    {
7416 	      bfd *sub;
7417 	      asection *o;
7418 
7419 	      for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
7420 		if (bfd_get_flavour (sub) == bfd_target_elf_flavour
7421 		    && (o = sub->sections) != NULL
7422 		    && o->sec_info_type != SEC_INFO_TYPE_JUST_SYMS)
7423 		  for (o = sub->sections; o != NULL; o = o->next)
7424 		    if (elf_section_data (o)->this_hdr.sh_type
7425 			== SHT_PREINIT_ARRAY)
7426 		      {
7427 			_bfd_error_handler
7428 			  (_("%pB: .preinit_array section is not allowed in DSO"),
7429 			   sub);
7430 			break;
7431 		      }
7432 
7433 	      bfd_set_error (bfd_error_nonrepresentable_section);
7434 	      return false;
7435 	    }
7436 
7437 	  if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
7438 	      || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
7439 	    return false;
7440 	}
7441       s = bfd_get_section_by_name (output_bfd, ".init_array");
7442       if (s != NULL && s->linker_has_input)
7443 	{
7444 	  if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
7445 	      || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
7446 	    return false;
7447 	}
7448       s = bfd_get_section_by_name (output_bfd, ".fini_array");
7449       if (s != NULL && s->linker_has_input)
7450 	{
7451 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
7452 	      || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
7453 	    return false;
7454 	}
7455 
7456       dynstr = bfd_get_linker_section (dynobj, ".dynstr");
7457       /* If .dynstr is excluded from the link, we don't want any of
7458 	 these tags.  Strictly, we should be checking each section
7459 	 individually;  This quick check covers for the case where
7460 	 someone does a /DISCARD/ : { *(*) }.  */
7461       if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
7462 	{
7463 	  bfd_size_type strsize;
7464 
7465 	  strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
7466 	  if ((info->emit_hash
7467 	       && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
7468 	      || (info->emit_gnu_hash
7469 		  && (bed->record_xhash_symbol == NULL
7470 		      && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0)))
7471 	      || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
7472 	      || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
7473 	      || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
7474 	      || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
7475 					      bed->s->sizeof_sym)
7476 	      || (info->gnu_flags_1
7477 		  && !_bfd_elf_add_dynamic_entry (info, DT_GNU_FLAGS_1,
7478 						  info->gnu_flags_1)))
7479 	    return false;
7480 	}
7481     }
7482 
7483   if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
7484     return false;
7485 
7486   /* The backend must work out the sizes of all the other dynamic
7487      sections.  */
7488   if (dynobj != NULL
7489       && bed->elf_backend_size_dynamic_sections != NULL
7490       && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
7491     return false;
7492 
7493   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
7494     {
7495       if (elf_tdata (output_bfd)->cverdefs)
7496 	{
7497 	  unsigned int crefs = elf_tdata (output_bfd)->cverdefs;
7498 
7499 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
7500 	      || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, crefs))
7501 	    return false;
7502 	}
7503 
7504       if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
7505 	{
7506 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
7507 	    return false;
7508 	}
7509       else if (info->flags & DF_BIND_NOW)
7510 	{
7511 	  if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
7512 	    return false;
7513 	}
7514 
7515       if (info->flags_1)
7516 	{
7517 	  if (bfd_link_executable (info))
7518 	    info->flags_1 &= ~ (DF_1_INITFIRST
7519 				| DF_1_NODELETE
7520 				| DF_1_NOOPEN);
7521 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
7522 	    return false;
7523 	}
7524 
7525       if (elf_tdata (output_bfd)->cverrefs)
7526 	{
7527 	  unsigned int crefs = elf_tdata (output_bfd)->cverrefs;
7528 
7529 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
7530 	      || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
7531 	    return false;
7532 	}
7533 
7534       if ((elf_tdata (output_bfd)->cverrefs == 0
7535 	   && elf_tdata (output_bfd)->cverdefs == 0)
7536 	  || _bfd_elf_link_renumber_dynsyms (output_bfd, info, NULL) <= 1)
7537 	{
7538 	  asection *s;
7539 
7540 	  s = bfd_get_linker_section (dynobj, ".gnu.version");
7541 	  s->flags |= SEC_EXCLUDE;
7542 	}
7543     }
7544   return true;
7545 }
7546 
7547 /* Find the first non-excluded output section.  We'll use its
7548    section symbol for some emitted relocs.  */
7549 void
_bfd_elf_init_1_index_section(bfd * output_bfd,struct bfd_link_info * info)7550 _bfd_elf_init_1_index_section (bfd *output_bfd, struct bfd_link_info *info)
7551 {
7552   asection *s;
7553   asection *found = NULL;
7554 
7555   for (s = output_bfd->sections; s != NULL; s = s->next)
7556     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7557 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7558       {
7559 	found = s;
7560 	if ((s->flags & SEC_THREAD_LOCAL) == 0)
7561 	  break;
7562       }
7563   elf_hash_table (info)->text_index_section = found;
7564 }
7565 
7566 /* Find two non-excluded output sections, one for code, one for data.
7567    We'll use their section symbols for some emitted relocs.  */
7568 void
_bfd_elf_init_2_index_sections(bfd * output_bfd,struct bfd_link_info * info)7569 _bfd_elf_init_2_index_sections (bfd *output_bfd, struct bfd_link_info *info)
7570 {
7571   asection *s;
7572   asection *found = NULL;
7573 
7574   /* Data first, since setting text_index_section changes
7575      _bfd_elf_omit_section_dynsym_default.  */
7576   for (s = output_bfd->sections; s != NULL; s = s->next)
7577     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7578 	&& !(s->flags & SEC_READONLY)
7579 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7580       {
7581 	found = s;
7582 	if ((s->flags & SEC_THREAD_LOCAL) == 0)
7583 	  break;
7584       }
7585   elf_hash_table (info)->data_index_section = found;
7586 
7587   for (s = output_bfd->sections; s != NULL; s = s->next)
7588     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7589 	&& (s->flags & SEC_READONLY)
7590 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7591       {
7592 	found = s;
7593 	break;
7594       }
7595   elf_hash_table (info)->text_index_section = found;
7596 }
7597 
7598 #define GNU_HASH_SECTION_NAME(bed)			    \
7599   (bed)->record_xhash_symbol != NULL ? ".MIPS.xhash" : ".gnu.hash"
7600 
7601 bool
bfd_elf_size_dynsym_hash_dynstr(bfd * output_bfd,struct bfd_link_info * info)7602 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
7603 {
7604   const struct elf_backend_data *bed;
7605   unsigned long section_sym_count;
7606   bfd_size_type dynsymcount = 0;
7607 
7608   if (!is_elf_hash_table (info->hash))
7609     return true;
7610 
7611   bed = get_elf_backend_data (output_bfd);
7612   (*bed->elf_backend_init_index_section) (output_bfd, info);
7613 
7614   /* Assign dynsym indices.  In a shared library we generate a section
7615      symbol for each output section, which come first.  Next come all
7616      of the back-end allocated local dynamic syms, followed by the rest
7617      of the global symbols.
7618 
7619      This is usually not needed for static binaries, however backends
7620      can request to always do it, e.g. the MIPS backend uses dynamic
7621      symbol counts to lay out GOT, which will be produced in the
7622      presence of GOT relocations even in static binaries (holding fixed
7623      data in that case, to satisfy those relocations).  */
7624 
7625   if (elf_hash_table (info)->dynamic_sections_created
7626       || bed->always_renumber_dynsyms)
7627     dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
7628 						  &section_sym_count);
7629 
7630   if (elf_hash_table (info)->dynamic_sections_created)
7631     {
7632       bfd *dynobj;
7633       asection *s;
7634       unsigned int dtagcount;
7635 
7636       dynobj = elf_hash_table (info)->dynobj;
7637 
7638       /* Work out the size of the symbol version section.  */
7639       s = bfd_get_linker_section (dynobj, ".gnu.version");
7640       BFD_ASSERT (s != NULL);
7641       if ((s->flags & SEC_EXCLUDE) == 0)
7642 	{
7643 	  s->size = dynsymcount * sizeof (Elf_External_Versym);
7644 	  s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7645 	  if (s->contents == NULL)
7646 	    return false;
7647 
7648 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
7649 	    return false;
7650 	}
7651 
7652       /* Set the size of the .dynsym and .hash sections.  We counted
7653 	 the number of dynamic symbols in elf_link_add_object_symbols.
7654 	 We will build the contents of .dynsym and .hash when we build
7655 	 the final symbol table, because until then we do not know the
7656 	 correct value to give the symbols.  We built the .dynstr
7657 	 section as we went along in elf_link_add_object_symbols.  */
7658       s = elf_hash_table (info)->dynsym;
7659       BFD_ASSERT (s != NULL);
7660       s->size = dynsymcount * bed->s->sizeof_sym;
7661 
7662       s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
7663       if (s->contents == NULL)
7664 	return false;
7665 
7666       /* The first entry in .dynsym is a dummy symbol.  Clear all the
7667 	 section syms, in case we don't output them all.  */
7668       ++section_sym_count;
7669       memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
7670 
7671       elf_hash_table (info)->bucketcount = 0;
7672 
7673       /* Compute the size of the hashing table.  As a side effect this
7674 	 computes the hash values for all the names we export.  */
7675       if (info->emit_hash)
7676 	{
7677 	  unsigned long int *hashcodes;
7678 	  struct hash_codes_info hashinf;
7679 	  bfd_size_type amt;
7680 	  unsigned long int nsyms;
7681 	  size_t bucketcount;
7682 	  size_t hash_entry_size;
7683 
7684 	  /* Compute the hash values for all exported symbols.  At the same
7685 	     time store the values in an array so that we could use them for
7686 	     optimizations.  */
7687 	  amt = dynsymcount * sizeof (unsigned long int);
7688 	  hashcodes = (unsigned long int *) bfd_malloc (amt);
7689 	  if (hashcodes == NULL)
7690 	    return false;
7691 	  hashinf.hashcodes = hashcodes;
7692 	  hashinf.error = false;
7693 
7694 	  /* Put all hash values in HASHCODES.  */
7695 	  elf_link_hash_traverse (elf_hash_table (info),
7696 				  elf_collect_hash_codes, &hashinf);
7697 	  if (hashinf.error)
7698 	    {
7699 	      free (hashcodes);
7700 	      return false;
7701 	    }
7702 
7703 	  nsyms = hashinf.hashcodes - hashcodes;
7704 	  bucketcount
7705 	    = compute_bucket_count (info, hashcodes, nsyms, 0);
7706 	  free (hashcodes);
7707 
7708 	  if (bucketcount == 0 && nsyms > 0)
7709 	    return false;
7710 
7711 	  elf_hash_table (info)->bucketcount = bucketcount;
7712 
7713 	  s = bfd_get_linker_section (dynobj, ".hash");
7714 	  BFD_ASSERT (s != NULL);
7715 	  hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
7716 	  s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
7717 	  s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7718 	  if (s->contents == NULL)
7719 	    return false;
7720 
7721 	  bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
7722 	  bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
7723 		   s->contents + hash_entry_size);
7724 	}
7725 
7726       if (info->emit_gnu_hash)
7727 	{
7728 	  size_t i, cnt;
7729 	  unsigned char *contents;
7730 	  struct collect_gnu_hash_codes cinfo;
7731 	  bfd_size_type amt;
7732 	  size_t bucketcount;
7733 
7734 	  memset (&cinfo, 0, sizeof (cinfo));
7735 
7736 	  /* Compute the hash values for all exported symbols.  At the same
7737 	     time store the values in an array so that we could use them for
7738 	     optimizations.  */
7739 	  amt = dynsymcount * 2 * sizeof (unsigned long int);
7740 	  cinfo.hashcodes = (long unsigned int *) bfd_malloc (amt);
7741 	  if (cinfo.hashcodes == NULL)
7742 	    return false;
7743 
7744 	  cinfo.hashval = cinfo.hashcodes + dynsymcount;
7745 	  cinfo.min_dynindx = -1;
7746 	  cinfo.output_bfd = output_bfd;
7747 	  cinfo.bed = bed;
7748 
7749 	  /* Put all hash values in HASHCODES.  */
7750 	  elf_link_hash_traverse (elf_hash_table (info),
7751 				  elf_collect_gnu_hash_codes, &cinfo);
7752 	  if (cinfo.error)
7753 	    {
7754 	      free (cinfo.hashcodes);
7755 	      return false;
7756 	    }
7757 
7758 	  bucketcount
7759 	    = compute_bucket_count (info, cinfo.hashcodes, cinfo.nsyms, 1);
7760 
7761 	  if (bucketcount == 0)
7762 	    {
7763 	      free (cinfo.hashcodes);
7764 	      return false;
7765 	    }
7766 
7767 	  s = bfd_get_linker_section (dynobj, GNU_HASH_SECTION_NAME (bed));
7768 	  BFD_ASSERT (s != NULL);
7769 
7770 	  if (cinfo.nsyms == 0)
7771 	    {
7772 	      /* Empty .gnu.hash or .MIPS.xhash section is special.  */
7773 	      BFD_ASSERT (cinfo.min_dynindx == -1);
7774 	      free (cinfo.hashcodes);
7775 	      s->size = 5 * 4 + bed->s->arch_size / 8;
7776 	      contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7777 	      if (contents == NULL)
7778 		return false;
7779 	      s->contents = contents;
7780 	      /* 1 empty bucket.  */
7781 	      bfd_put_32 (output_bfd, 1, contents);
7782 	      /* SYMIDX above the special symbol 0.  */
7783 	      bfd_put_32 (output_bfd, 1, contents + 4);
7784 	      /* Just one word for bitmask.  */
7785 	      bfd_put_32 (output_bfd, 1, contents + 8);
7786 	      /* Only hash fn bloom filter.  */
7787 	      bfd_put_32 (output_bfd, 0, contents + 12);
7788 	      /* No hashes are valid - empty bitmask.  */
7789 	      bfd_put (bed->s->arch_size, output_bfd, 0, contents + 16);
7790 	      /* No hashes in the only bucket.  */
7791 	      bfd_put_32 (output_bfd, 0,
7792 			  contents + 16 + bed->s->arch_size / 8);
7793 	    }
7794 	  else
7795 	    {
7796 	      unsigned long int maskwords, maskbitslog2, x;
7797 	      BFD_ASSERT (cinfo.min_dynindx != -1);
7798 
7799 	      x = cinfo.nsyms;
7800 	      maskbitslog2 = 1;
7801 	      while ((x >>= 1) != 0)
7802 		++maskbitslog2;
7803 	      if (maskbitslog2 < 3)
7804 		maskbitslog2 = 5;
7805 	      else if ((1 << (maskbitslog2 - 2)) & cinfo.nsyms)
7806 		maskbitslog2 = maskbitslog2 + 3;
7807 	      else
7808 		maskbitslog2 = maskbitslog2 + 2;
7809 	      if (bed->s->arch_size == 64)
7810 		{
7811 		  if (maskbitslog2 == 5)
7812 		    maskbitslog2 = 6;
7813 		  cinfo.shift1 = 6;
7814 		}
7815 	      else
7816 		cinfo.shift1 = 5;
7817 	      cinfo.mask = (1 << cinfo.shift1) - 1;
7818 	      cinfo.shift2 = maskbitslog2;
7819 	      cinfo.maskbits = 1 << maskbitslog2;
7820 	      maskwords = 1 << (maskbitslog2 - cinfo.shift1);
7821 	      amt = bucketcount * sizeof (unsigned long int) * 2;
7822 	      amt += maskwords * sizeof (bfd_vma);
7823 	      cinfo.bitmask = (bfd_vma *) bfd_malloc (amt);
7824 	      if (cinfo.bitmask == NULL)
7825 		{
7826 		  free (cinfo.hashcodes);
7827 		  return false;
7828 		}
7829 
7830 	      cinfo.counts = (long unsigned int *) (cinfo.bitmask + maskwords);
7831 	      cinfo.indx = cinfo.counts + bucketcount;
7832 	      cinfo.symindx = dynsymcount - cinfo.nsyms;
7833 	      memset (cinfo.bitmask, 0, maskwords * sizeof (bfd_vma));
7834 
7835 	      /* Determine how often each hash bucket is used.  */
7836 	      memset (cinfo.counts, 0, bucketcount * sizeof (cinfo.counts[0]));
7837 	      for (i = 0; i < cinfo.nsyms; ++i)
7838 		++cinfo.counts[cinfo.hashcodes[i] % bucketcount];
7839 
7840 	      for (i = 0, cnt = cinfo.symindx; i < bucketcount; ++i)
7841 		if (cinfo.counts[i] != 0)
7842 		  {
7843 		    cinfo.indx[i] = cnt;
7844 		    cnt += cinfo.counts[i];
7845 		  }
7846 	      BFD_ASSERT (cnt == dynsymcount);
7847 	      cinfo.bucketcount = bucketcount;
7848 	      cinfo.local_indx = cinfo.min_dynindx;
7849 
7850 	      s->size = (4 + bucketcount + cinfo.nsyms) * 4;
7851 	      s->size += cinfo.maskbits / 8;
7852 	      if (bed->record_xhash_symbol != NULL)
7853 		s->size += cinfo.nsyms * 4;
7854 	      contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7855 	      if (contents == NULL)
7856 		{
7857 		  free (cinfo.bitmask);
7858 		  free (cinfo.hashcodes);
7859 		  return false;
7860 		}
7861 
7862 	      s->contents = contents;
7863 	      bfd_put_32 (output_bfd, bucketcount, contents);
7864 	      bfd_put_32 (output_bfd, cinfo.symindx, contents + 4);
7865 	      bfd_put_32 (output_bfd, maskwords, contents + 8);
7866 	      bfd_put_32 (output_bfd, cinfo.shift2, contents + 12);
7867 	      contents += 16 + cinfo.maskbits / 8;
7868 
7869 	      for (i = 0; i < bucketcount; ++i)
7870 		{
7871 		  if (cinfo.counts[i] == 0)
7872 		    bfd_put_32 (output_bfd, 0, contents);
7873 		  else
7874 		    bfd_put_32 (output_bfd, cinfo.indx[i], contents);
7875 		  contents += 4;
7876 		}
7877 
7878 	      cinfo.contents = contents;
7879 
7880 	      cinfo.xlat = contents + cinfo.nsyms * 4 - s->contents;
7881 	      /* Renumber dynamic symbols, if populating .gnu.hash section.
7882 		 If using .MIPS.xhash, populate the translation table.  */
7883 	      elf_link_hash_traverse (elf_hash_table (info),
7884 				      elf_gnu_hash_process_symidx, &cinfo);
7885 
7886 	      contents = s->contents + 16;
7887 	      for (i = 0; i < maskwords; ++i)
7888 		{
7889 		  bfd_put (bed->s->arch_size, output_bfd, cinfo.bitmask[i],
7890 			   contents);
7891 		  contents += bed->s->arch_size / 8;
7892 		}
7893 
7894 	      free (cinfo.bitmask);
7895 	      free (cinfo.hashcodes);
7896 	    }
7897 	}
7898 
7899       s = bfd_get_linker_section (dynobj, ".dynstr");
7900       BFD_ASSERT (s != NULL);
7901 
7902       elf_finalize_dynstr (output_bfd, info);
7903 
7904       s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
7905 
7906       for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
7907 	if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
7908 	  return false;
7909     }
7910 
7911   return true;
7912 }
7913 
7914 /* Make sure sec_info_type is cleared if sec_info is cleared too.  */
7915 
7916 static void
merge_sections_remove_hook(bfd * abfd ATTRIBUTE_UNUSED,asection * sec)7917 merge_sections_remove_hook (bfd *abfd ATTRIBUTE_UNUSED,
7918 			    asection *sec)
7919 {
7920   BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_MERGE);
7921   sec->sec_info_type = SEC_INFO_TYPE_NONE;
7922 }
7923 
7924 /* Finish SHF_MERGE section merging.  */
7925 
7926 bool
_bfd_elf_merge_sections(bfd * obfd,struct bfd_link_info * info)7927 _bfd_elf_merge_sections (bfd *obfd, struct bfd_link_info *info)
7928 {
7929   bfd *ibfd;
7930   asection *sec;
7931 
7932   if (!is_elf_hash_table (info->hash))
7933     return false;
7934 
7935   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
7936     if ((ibfd->flags & DYNAMIC) == 0
7937 	&& bfd_get_flavour (ibfd) == bfd_target_elf_flavour
7938 	&& (elf_elfheader (ibfd)->e_ident[EI_CLASS]
7939 	    == get_elf_backend_data (obfd)->s->elfclass))
7940       for (sec = ibfd->sections; sec != NULL; sec = sec->next)
7941 	if ((sec->flags & SEC_MERGE) != 0
7942 	    && !bfd_is_abs_section (sec->output_section))
7943 	  {
7944 	    struct bfd_elf_section_data *secdata;
7945 
7946 	    secdata = elf_section_data (sec);
7947 	    if (! _bfd_add_merge_section (obfd,
7948 					  &elf_hash_table (info)->merge_info,
7949 					  sec, &secdata->sec_info))
7950 	      return false;
7951 	    else if (secdata->sec_info)
7952 	      sec->sec_info_type = SEC_INFO_TYPE_MERGE;
7953 	  }
7954 
7955   if (elf_hash_table (info)->merge_info != NULL)
7956     _bfd_merge_sections (obfd, info, elf_hash_table (info)->merge_info,
7957 			 merge_sections_remove_hook);
7958   return true;
7959 }
7960 
7961 /* Create an entry in an ELF linker hash table.  */
7962 
7963 struct bfd_hash_entry *
_bfd_elf_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)7964 _bfd_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
7965 			    struct bfd_hash_table *table,
7966 			    const char *string)
7967 {
7968   /* Allocate the structure if it has not already been allocated by a
7969      subclass.  */
7970   if (entry == NULL)
7971     {
7972       entry = (struct bfd_hash_entry *)
7973 	bfd_hash_allocate (table, sizeof (struct elf_link_hash_entry));
7974       if (entry == NULL)
7975 	return entry;
7976     }
7977 
7978   /* Call the allocation method of the superclass.  */
7979   entry = _bfd_link_hash_newfunc (entry, table, string);
7980   if (entry != NULL)
7981     {
7982       struct elf_link_hash_entry *ret = (struct elf_link_hash_entry *) entry;
7983       struct elf_link_hash_table *htab = (struct elf_link_hash_table *) table;
7984 
7985       /* Set local fields.  */
7986       ret->indx = -1;
7987       ret->dynindx = -1;
7988       ret->got = htab->init_got_refcount;
7989       ret->plt = htab->init_plt_refcount;
7990       memset (&ret->size, 0, (sizeof (struct elf_link_hash_entry)
7991 			      - offsetof (struct elf_link_hash_entry, size)));
7992       /* Assume that we have been called by a non-ELF symbol reader.
7993 	 This flag is then reset by the code which reads an ELF input
7994 	 file.  This ensures that a symbol created by a non-ELF symbol
7995 	 reader will have the flag set correctly.  */
7996       ret->non_elf = 1;
7997     }
7998 
7999   return entry;
8000 }
8001 
8002 /* Copy data from an indirect symbol to its direct symbol, hiding the
8003    old indirect symbol.  Also used for copying flags to a weakdef.  */
8004 
8005 void
_bfd_elf_link_hash_copy_indirect(struct bfd_link_info * info,struct elf_link_hash_entry * dir,struct elf_link_hash_entry * ind)8006 _bfd_elf_link_hash_copy_indirect (struct bfd_link_info *info,
8007 				  struct elf_link_hash_entry *dir,
8008 				  struct elf_link_hash_entry *ind)
8009 {
8010   struct elf_link_hash_table *htab;
8011 
8012   if (ind->dyn_relocs != NULL)
8013     {
8014       if (dir->dyn_relocs != NULL)
8015 	{
8016 	  struct elf_dyn_relocs **pp;
8017 	  struct elf_dyn_relocs *p;
8018 
8019 	  /* Add reloc counts against the indirect sym to the direct sym
8020 	     list.  Merge any entries against the same section.  */
8021 	  for (pp = &ind->dyn_relocs; (p = *pp) != NULL; )
8022 	    {
8023 	      struct elf_dyn_relocs *q;
8024 
8025 	      for (q = dir->dyn_relocs; q != NULL; q = q->next)
8026 		if (q->sec == p->sec)
8027 		  {
8028 		    q->pc_count += p->pc_count;
8029 		    q->count += p->count;
8030 		    *pp = p->next;
8031 		    break;
8032 		  }
8033 	      if (q == NULL)
8034 		pp = &p->next;
8035 	    }
8036 	  *pp = dir->dyn_relocs;
8037 	}
8038 
8039       dir->dyn_relocs = ind->dyn_relocs;
8040       ind->dyn_relocs = NULL;
8041     }
8042 
8043   /* Copy down any references that we may have already seen to the
8044      symbol which just became indirect.  */
8045 
8046   if (dir->versioned != versioned_hidden)
8047     dir->ref_dynamic |= ind->ref_dynamic;
8048   dir->ref_regular |= ind->ref_regular;
8049   dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
8050   dir->non_got_ref |= ind->non_got_ref;
8051   dir->needs_plt |= ind->needs_plt;
8052   dir->pointer_equality_needed |= ind->pointer_equality_needed;
8053 
8054   if (ind->root.type != bfd_link_hash_indirect)
8055     return;
8056 
8057   /* Copy over the global and procedure linkage table refcount entries.
8058      These may have been already set up by a check_relocs routine.  */
8059   htab = elf_hash_table (info);
8060   if (ind->got.refcount > htab->init_got_refcount.refcount)
8061     {
8062       if (dir->got.refcount < 0)
8063 	dir->got.refcount = 0;
8064       dir->got.refcount += ind->got.refcount;
8065       ind->got.refcount = htab->init_got_refcount.refcount;
8066     }
8067 
8068   if (ind->plt.refcount > htab->init_plt_refcount.refcount)
8069     {
8070       if (dir->plt.refcount < 0)
8071 	dir->plt.refcount = 0;
8072       dir->plt.refcount += ind->plt.refcount;
8073       ind->plt.refcount = htab->init_plt_refcount.refcount;
8074     }
8075 
8076   if (ind->dynindx != -1)
8077     {
8078       if (dir->dynindx != -1)
8079 	_bfd_elf_strtab_delref (htab->dynstr, dir->dynstr_index);
8080       dir->dynindx = ind->dynindx;
8081       dir->dynstr_index = ind->dynstr_index;
8082       ind->dynindx = -1;
8083       ind->dynstr_index = 0;
8084     }
8085 }
8086 
8087 void
_bfd_elf_link_hash_hide_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,bool force_local)8088 _bfd_elf_link_hash_hide_symbol (struct bfd_link_info *info,
8089 				struct elf_link_hash_entry *h,
8090 				bool force_local)
8091 {
8092   /* STT_GNU_IFUNC symbol must go through PLT.  */
8093   if (h->type != STT_GNU_IFUNC)
8094     {
8095       h->plt = elf_hash_table (info)->init_plt_offset;
8096       h->needs_plt = 0;
8097     }
8098   if (force_local)
8099     {
8100       h->forced_local = 1;
8101       if (h->dynindx != -1)
8102 	{
8103 	  _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
8104 				  h->dynstr_index);
8105 	  h->dynindx = -1;
8106 	  h->dynstr_index = 0;
8107 	}
8108     }
8109 }
8110 
8111 /* Hide a symbol. */
8112 
8113 void
_bfd_elf_link_hide_symbol(bfd * output_bfd,struct bfd_link_info * info,struct bfd_link_hash_entry * h)8114 _bfd_elf_link_hide_symbol (bfd *output_bfd,
8115 			   struct bfd_link_info *info,
8116 			   struct bfd_link_hash_entry *h)
8117 {
8118   if (is_elf_hash_table (info->hash))
8119     {
8120       const struct elf_backend_data *bed
8121 	= get_elf_backend_data (output_bfd);
8122       struct elf_link_hash_entry *eh
8123 	= (struct elf_link_hash_entry *) h;
8124       bed->elf_backend_hide_symbol (info, eh, true);
8125       eh->def_dynamic = 0;
8126       eh->ref_dynamic = 0;
8127       eh->dynamic_def = 0;
8128     }
8129 }
8130 
8131 /* Initialize an ELF linker hash table.  *TABLE has been zeroed by our
8132    caller.  */
8133 
8134 bool
_bfd_elf_link_hash_table_init(struct elf_link_hash_table * table,bfd * abfd,struct bfd_hash_entry * (* newfunc)(struct bfd_hash_entry *,struct bfd_hash_table *,const char *),unsigned int entsize,enum elf_target_id target_id)8135 _bfd_elf_link_hash_table_init
8136   (struct elf_link_hash_table *table,
8137    bfd *abfd,
8138    struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
8139 				      struct bfd_hash_table *,
8140 				      const char *),
8141    unsigned int entsize,
8142    enum elf_target_id target_id)
8143 {
8144   bool ret;
8145   int can_refcount = get_elf_backend_data (abfd)->can_refcount;
8146 
8147   table->init_got_refcount.refcount = can_refcount - 1;
8148   table->init_plt_refcount.refcount = can_refcount - 1;
8149   table->init_got_offset.offset = -(bfd_vma) 1;
8150   table->init_plt_offset.offset = -(bfd_vma) 1;
8151   /* The first dynamic symbol is a dummy.  */
8152   table->dynsymcount = 1;
8153 
8154   ret = _bfd_link_hash_table_init (&table->root, abfd, newfunc, entsize);
8155 
8156   table->root.type = bfd_link_elf_hash_table;
8157   table->hash_table_id = target_id;
8158   table->target_os = get_elf_backend_data (abfd)->target_os;
8159 
8160   return ret;
8161 }
8162 
8163 /* Create an ELF linker hash table.  */
8164 
8165 struct bfd_link_hash_table *
_bfd_elf_link_hash_table_create(bfd * abfd)8166 _bfd_elf_link_hash_table_create (bfd *abfd)
8167 {
8168   struct elf_link_hash_table *ret;
8169   size_t amt = sizeof (struct elf_link_hash_table);
8170 
8171   ret = (struct elf_link_hash_table *) bfd_zmalloc (amt);
8172   if (ret == NULL)
8173     return NULL;
8174 
8175   if (! _bfd_elf_link_hash_table_init (ret, abfd, _bfd_elf_link_hash_newfunc,
8176 				       sizeof (struct elf_link_hash_entry),
8177 				       GENERIC_ELF_DATA))
8178     {
8179       free (ret);
8180       return NULL;
8181     }
8182   ret->root.hash_table_free = _bfd_elf_link_hash_table_free;
8183 
8184   return &ret->root;
8185 }
8186 
8187 /* Destroy an ELF linker hash table.  */
8188 
8189 void
_bfd_elf_link_hash_table_free(bfd * obfd)8190 _bfd_elf_link_hash_table_free (bfd *obfd)
8191 {
8192   struct elf_link_hash_table *htab;
8193 
8194   htab = (struct elf_link_hash_table *) obfd->link.hash;
8195   if (htab->dynstr != NULL)
8196     _bfd_elf_strtab_free (htab->dynstr);
8197   _bfd_merge_sections_free (htab->merge_info);
8198   _bfd_generic_link_hash_table_free (obfd);
8199 }
8200 
8201 /* This is a hook for the ELF emulation code in the generic linker to
8202    tell the backend linker what file name to use for the DT_NEEDED
8203    entry for a dynamic object.  */
8204 
8205 void
bfd_elf_set_dt_needed_name(bfd * abfd,const char * name)8206 bfd_elf_set_dt_needed_name (bfd *abfd, const char *name)
8207 {
8208   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
8209       && bfd_get_format (abfd) == bfd_object)
8210     elf_dt_name (abfd) = name;
8211 }
8212 
8213 int
bfd_elf_get_dyn_lib_class(bfd * abfd)8214 bfd_elf_get_dyn_lib_class (bfd *abfd)
8215 {
8216   int lib_class;
8217   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
8218       && bfd_get_format (abfd) == bfd_object)
8219     lib_class = elf_dyn_lib_class (abfd);
8220   else
8221     lib_class = 0;
8222   return lib_class;
8223 }
8224 
8225 void
bfd_elf_set_dyn_lib_class(bfd * abfd,enum dynamic_lib_link_class lib_class)8226 bfd_elf_set_dyn_lib_class (bfd *abfd, enum dynamic_lib_link_class lib_class)
8227 {
8228   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
8229       && bfd_get_format (abfd) == bfd_object)
8230     elf_dyn_lib_class (abfd) = lib_class;
8231 }
8232 
8233 /* Get the list of DT_NEEDED entries for a link.  This is a hook for
8234    the linker ELF emulation code.  */
8235 
8236 struct bfd_link_needed_list *
bfd_elf_get_needed_list(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)8237 bfd_elf_get_needed_list (bfd *abfd ATTRIBUTE_UNUSED,
8238 			 struct bfd_link_info *info)
8239 {
8240   if (! is_elf_hash_table (info->hash))
8241     return NULL;
8242   return elf_hash_table (info)->needed;
8243 }
8244 
8245 /* Get the list of DT_RPATH/DT_RUNPATH entries for a link.  This is a
8246    hook for the linker ELF emulation code.  */
8247 
8248 struct bfd_link_needed_list *
bfd_elf_get_runpath_list(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)8249 bfd_elf_get_runpath_list (bfd *abfd ATTRIBUTE_UNUSED,
8250 			  struct bfd_link_info *info)
8251 {
8252   if (! is_elf_hash_table (info->hash))
8253     return NULL;
8254   return elf_hash_table (info)->runpath;
8255 }
8256 
8257 /* Get the name actually used for a dynamic object for a link.  This
8258    is the SONAME entry if there is one.  Otherwise, it is the string
8259    passed to bfd_elf_set_dt_needed_name, or it is the filename.  */
8260 
8261 const char *
bfd_elf_get_dt_soname(bfd * abfd)8262 bfd_elf_get_dt_soname (bfd *abfd)
8263 {
8264   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
8265       && bfd_get_format (abfd) == bfd_object)
8266     return elf_dt_name (abfd);
8267   return NULL;
8268 }
8269 
8270 /* Get the list of DT_NEEDED entries from a BFD.  This is a hook for
8271    the ELF linker emulation code.  */
8272 
8273 bool
bfd_elf_get_bfd_needed_list(bfd * abfd,struct bfd_link_needed_list ** pneeded)8274 bfd_elf_get_bfd_needed_list (bfd *abfd,
8275 			     struct bfd_link_needed_list **pneeded)
8276 {
8277   asection *s;
8278   bfd_byte *dynbuf = NULL;
8279   unsigned int elfsec;
8280   unsigned long shlink;
8281   bfd_byte *extdyn, *extdynend;
8282   size_t extdynsize;
8283   void (*swap_dyn_in) (bfd *, const void *, Elf_Internal_Dyn *);
8284 
8285   *pneeded = NULL;
8286 
8287   if (bfd_get_flavour (abfd) != bfd_target_elf_flavour
8288       || bfd_get_format (abfd) != bfd_object)
8289     return true;
8290 
8291   s = bfd_get_section_by_name (abfd, ".dynamic");
8292   if (s == NULL || s->size == 0 || (s->flags & SEC_HAS_CONTENTS) == 0)
8293     return true;
8294 
8295   if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
8296     goto error_return;
8297 
8298   elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
8299   if (elfsec == SHN_BAD)
8300     goto error_return;
8301 
8302   shlink = elf_elfsections (abfd)[elfsec]->sh_link;
8303 
8304   extdynsize = get_elf_backend_data (abfd)->s->sizeof_dyn;
8305   swap_dyn_in = get_elf_backend_data (abfd)->s->swap_dyn_in;
8306 
8307   for (extdyn = dynbuf, extdynend = dynbuf + s->size;
8308        (size_t) (extdynend - extdyn) >= extdynsize;
8309        extdyn += extdynsize)
8310     {
8311       Elf_Internal_Dyn dyn;
8312 
8313       (*swap_dyn_in) (abfd, extdyn, &dyn);
8314 
8315       if (dyn.d_tag == DT_NULL)
8316 	break;
8317 
8318       if (dyn.d_tag == DT_NEEDED)
8319 	{
8320 	  const char *string;
8321 	  struct bfd_link_needed_list *l;
8322 	  unsigned int tagv = dyn.d_un.d_val;
8323 	  size_t amt;
8324 
8325 	  string = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
8326 	  if (string == NULL)
8327 	    goto error_return;
8328 
8329 	  amt = sizeof *l;
8330 	  l = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
8331 	  if (l == NULL)
8332 	    goto error_return;
8333 
8334 	  l->by = abfd;
8335 	  l->name = string;
8336 	  l->next = *pneeded;
8337 	  *pneeded = l;
8338 	}
8339     }
8340 
8341   free (dynbuf);
8342 
8343   return true;
8344 
8345  error_return:
8346   free (dynbuf);
8347   return false;
8348 }
8349 
8350 struct elf_symbuf_symbol
8351 {
8352   unsigned long st_name;	/* Symbol name, index in string tbl */
8353   unsigned char st_info;	/* Type and binding attributes */
8354   unsigned char st_other;	/* Visibilty, and target specific */
8355 };
8356 
8357 struct elf_symbuf_head
8358 {
8359   struct elf_symbuf_symbol *ssym;
8360   size_t count;
8361   unsigned int st_shndx;
8362 };
8363 
8364 struct elf_symbol
8365 {
8366   union
8367     {
8368       Elf_Internal_Sym *isym;
8369       struct elf_symbuf_symbol *ssym;
8370       void *p;
8371     } u;
8372   const char *name;
8373 };
8374 
8375 /* Sort references to symbols by ascending section number.  */
8376 
8377 static int
elf_sort_elf_symbol(const void * arg1,const void * arg2)8378 elf_sort_elf_symbol (const void *arg1, const void *arg2)
8379 {
8380   const Elf_Internal_Sym *s1 = *(const Elf_Internal_Sym **) arg1;
8381   const Elf_Internal_Sym *s2 = *(const Elf_Internal_Sym **) arg2;
8382 
8383   if (s1->st_shndx != s2->st_shndx)
8384     return s1->st_shndx > s2->st_shndx ? 1 : -1;
8385   /* Final sort by the address of the sym in the symbuf ensures
8386      a stable sort.  */
8387   if (s1 != s2)
8388     return s1 > s2 ? 1 : -1;
8389   return 0;
8390 }
8391 
8392 static int
elf_sym_name_compare(const void * arg1,const void * arg2)8393 elf_sym_name_compare (const void *arg1, const void *arg2)
8394 {
8395   const struct elf_symbol *s1 = (const struct elf_symbol *) arg1;
8396   const struct elf_symbol *s2 = (const struct elf_symbol *) arg2;
8397   int ret = strcmp (s1->name, s2->name);
8398   if (ret != 0)
8399     return ret;
8400   if (s1->u.p != s2->u.p)
8401     return s1->u.p > s2->u.p ? 1 : -1;
8402   return 0;
8403 }
8404 
8405 static struct elf_symbuf_head *
elf_create_symbuf(size_t symcount,Elf_Internal_Sym * isymbuf)8406 elf_create_symbuf (size_t symcount, Elf_Internal_Sym *isymbuf)
8407 {
8408   Elf_Internal_Sym **ind, **indbufend, **indbuf;
8409   struct elf_symbuf_symbol *ssym;
8410   struct elf_symbuf_head *ssymbuf, *ssymhead;
8411   size_t i, shndx_count, total_size, amt;
8412 
8413   amt = symcount * sizeof (*indbuf);
8414   indbuf = (Elf_Internal_Sym **) bfd_malloc (amt);
8415   if (indbuf == NULL)
8416     return NULL;
8417 
8418   for (ind = indbuf, i = 0; i < symcount; i++)
8419     if (isymbuf[i].st_shndx != SHN_UNDEF)
8420       *ind++ = &isymbuf[i];
8421   indbufend = ind;
8422 
8423   qsort (indbuf, indbufend - indbuf, sizeof (Elf_Internal_Sym *),
8424 	 elf_sort_elf_symbol);
8425 
8426   shndx_count = 0;
8427   if (indbufend > indbuf)
8428     for (ind = indbuf, shndx_count++; ind < indbufend - 1; ind++)
8429       if (ind[0]->st_shndx != ind[1]->st_shndx)
8430 	shndx_count++;
8431 
8432   total_size = ((shndx_count + 1) * sizeof (*ssymbuf)
8433 		+ (indbufend - indbuf) * sizeof (*ssym));
8434   ssymbuf = (struct elf_symbuf_head *) bfd_malloc (total_size);
8435   if (ssymbuf == NULL)
8436     {
8437       free (indbuf);
8438       return NULL;
8439     }
8440 
8441   ssym = (struct elf_symbuf_symbol *) (ssymbuf + shndx_count + 1);
8442   ssymbuf->ssym = NULL;
8443   ssymbuf->count = shndx_count;
8444   ssymbuf->st_shndx = 0;
8445   for (ssymhead = ssymbuf, ind = indbuf; ind < indbufend; ssym++, ind++)
8446     {
8447       if (ind == indbuf || ssymhead->st_shndx != (*ind)->st_shndx)
8448 	{
8449 	  ssymhead++;
8450 	  ssymhead->ssym = ssym;
8451 	  ssymhead->count = 0;
8452 	  ssymhead->st_shndx = (*ind)->st_shndx;
8453 	}
8454       ssym->st_name = (*ind)->st_name;
8455       ssym->st_info = (*ind)->st_info;
8456       ssym->st_other = (*ind)->st_other;
8457       ssymhead->count++;
8458     }
8459   BFD_ASSERT ((size_t) (ssymhead - ssymbuf) == shndx_count
8460 	      && (uintptr_t) ssym - (uintptr_t) ssymbuf == total_size);
8461 
8462   free (indbuf);
8463   return ssymbuf;
8464 }
8465 
8466 /* Check if 2 sections define the same set of local and global
8467    symbols.  */
8468 
8469 static bool
bfd_elf_match_symbols_in_sections(asection * sec1,asection * sec2,struct bfd_link_info * info)8470 bfd_elf_match_symbols_in_sections (asection *sec1, asection *sec2,
8471 				   struct bfd_link_info *info)
8472 {
8473   bfd *bfd1, *bfd2;
8474   const struct elf_backend_data *bed1, *bed2;
8475   Elf_Internal_Shdr *hdr1, *hdr2;
8476   size_t symcount1, symcount2;
8477   Elf_Internal_Sym *isymbuf1, *isymbuf2;
8478   struct elf_symbuf_head *ssymbuf1, *ssymbuf2;
8479   Elf_Internal_Sym *isym, *isymend;
8480   struct elf_symbol *symtable1 = NULL, *symtable2 = NULL;
8481   size_t count1, count2, sec_count1, sec_count2, i;
8482   unsigned int shndx1, shndx2;
8483   bool result;
8484   bool ignore_section_symbol_p;
8485 
8486   bfd1 = sec1->owner;
8487   bfd2 = sec2->owner;
8488 
8489   /* Both sections have to be in ELF.  */
8490   if (bfd_get_flavour (bfd1) != bfd_target_elf_flavour
8491       || bfd_get_flavour (bfd2) != bfd_target_elf_flavour)
8492     return false;
8493 
8494   if (elf_section_type (sec1) != elf_section_type (sec2))
8495     return false;
8496 
8497   shndx1 = _bfd_elf_section_from_bfd_section (bfd1, sec1);
8498   shndx2 = _bfd_elf_section_from_bfd_section (bfd2, sec2);
8499   if (shndx1 == SHN_BAD || shndx2 == SHN_BAD)
8500     return false;
8501 
8502   bed1 = get_elf_backend_data (bfd1);
8503   bed2 = get_elf_backend_data (bfd2);
8504   hdr1 = &elf_tdata (bfd1)->symtab_hdr;
8505   symcount1 = hdr1->sh_size / bed1->s->sizeof_sym;
8506   hdr2 = &elf_tdata (bfd2)->symtab_hdr;
8507   symcount2 = hdr2->sh_size / bed2->s->sizeof_sym;
8508 
8509   if (symcount1 == 0 || symcount2 == 0)
8510     return false;
8511 
8512   result = false;
8513   isymbuf1 = NULL;
8514   isymbuf2 = NULL;
8515   ssymbuf1 = (struct elf_symbuf_head *) elf_tdata (bfd1)->symbuf;
8516   ssymbuf2 = (struct elf_symbuf_head *) elf_tdata (bfd2)->symbuf;
8517 
8518   /* Ignore section symbols only when matching non-debugging sections
8519      or linkonce section with comdat section.  */
8520   ignore_section_symbol_p
8521     = ((sec1->flags & SEC_DEBUGGING) == 0
8522        || ((elf_section_flags (sec1) & SHF_GROUP)
8523 	   != (elf_section_flags (sec2) & SHF_GROUP)));
8524 
8525   if (ssymbuf1 == NULL)
8526     {
8527       isymbuf1 = bfd_elf_get_elf_syms (bfd1, hdr1, symcount1, 0,
8528 				       NULL, NULL, NULL);
8529       if (isymbuf1 == NULL)
8530 	goto done;
8531 
8532       if (info != NULL && !info->reduce_memory_overheads)
8533 	{
8534 	  ssymbuf1 = elf_create_symbuf (symcount1, isymbuf1);
8535 	  elf_tdata (bfd1)->symbuf = ssymbuf1;
8536 	}
8537     }
8538 
8539   if (ssymbuf1 == NULL || ssymbuf2 == NULL)
8540     {
8541       isymbuf2 = bfd_elf_get_elf_syms (bfd2, hdr2, symcount2, 0,
8542 				       NULL, NULL, NULL);
8543       if (isymbuf2 == NULL)
8544 	goto done;
8545 
8546       if (ssymbuf1 != NULL && info != NULL && !info->reduce_memory_overheads)
8547 	{
8548 	  ssymbuf2 = elf_create_symbuf (symcount2, isymbuf2);
8549 	  elf_tdata (bfd2)->symbuf = ssymbuf2;
8550 	}
8551     }
8552 
8553   if (ssymbuf1 != NULL && ssymbuf2 != NULL)
8554     {
8555       /* Optimized faster version.  */
8556       size_t lo, hi, mid;
8557       struct elf_symbol *symp;
8558       struct elf_symbuf_symbol *ssym, *ssymend;
8559 
8560       lo = 0;
8561       hi = ssymbuf1->count;
8562       ssymbuf1++;
8563       count1 = 0;
8564       sec_count1 = 0;
8565       while (lo < hi)
8566 	{
8567 	  mid = (lo + hi) / 2;
8568 	  if (shndx1 < ssymbuf1[mid].st_shndx)
8569 	    hi = mid;
8570 	  else if (shndx1 > ssymbuf1[mid].st_shndx)
8571 	    lo = mid + 1;
8572 	  else
8573 	    {
8574 	      count1 = ssymbuf1[mid].count;
8575 	      ssymbuf1 += mid;
8576 	      break;
8577 	    }
8578 	}
8579       if (ignore_section_symbol_p)
8580 	{
8581 	  for (i = 0; i < count1; i++)
8582 	    if (ELF_ST_TYPE (ssymbuf1->ssym[i].st_info) == STT_SECTION)
8583 	      sec_count1++;
8584 	  count1 -= sec_count1;
8585 	}
8586 
8587       lo = 0;
8588       hi = ssymbuf2->count;
8589       ssymbuf2++;
8590       count2 = 0;
8591       sec_count2 = 0;
8592       while (lo < hi)
8593 	{
8594 	  mid = (lo + hi) / 2;
8595 	  if (shndx2 < ssymbuf2[mid].st_shndx)
8596 	    hi = mid;
8597 	  else if (shndx2 > ssymbuf2[mid].st_shndx)
8598 	    lo = mid + 1;
8599 	  else
8600 	    {
8601 	      count2 = ssymbuf2[mid].count;
8602 	      ssymbuf2 += mid;
8603 	      break;
8604 	    }
8605 	}
8606       if (ignore_section_symbol_p)
8607 	{
8608 	  for (i = 0; i < count2; i++)
8609 	    if (ELF_ST_TYPE (ssymbuf2->ssym[i].st_info) == STT_SECTION)
8610 	      sec_count2++;
8611 	  count2 -= sec_count2;
8612 	}
8613 
8614       if (count1 == 0 || count2 == 0 || count1 != count2)
8615 	goto done;
8616 
8617       symtable1
8618 	= (struct elf_symbol *) bfd_malloc (count1 * sizeof (*symtable1));
8619       symtable2
8620 	= (struct elf_symbol *) bfd_malloc (count2 * sizeof (*symtable2));
8621       if (symtable1 == NULL || symtable2 == NULL)
8622 	goto done;
8623 
8624       symp = symtable1;
8625       for (ssym = ssymbuf1->ssym, ssymend = ssym + count1 + sec_count1;
8626 	   ssym < ssymend; ssym++)
8627 	if (sec_count1 == 0
8628 	    || ELF_ST_TYPE (ssym->st_info) != STT_SECTION)
8629 	  {
8630 	    symp->u.ssym = ssym;
8631 	    symp->name = bfd_elf_string_from_elf_section (bfd1,
8632 							  hdr1->sh_link,
8633 							  ssym->st_name);
8634 	    symp++;
8635 	  }
8636 
8637       symp = symtable2;
8638       for (ssym = ssymbuf2->ssym, ssymend = ssym + count2 + sec_count2;
8639 	   ssym < ssymend; ssym++)
8640 	if (sec_count2 == 0
8641 	    || ELF_ST_TYPE (ssym->st_info) != STT_SECTION)
8642 	  {
8643 	    symp->u.ssym = ssym;
8644 	    symp->name = bfd_elf_string_from_elf_section (bfd2,
8645 							  hdr2->sh_link,
8646 							  ssym->st_name);
8647 	    symp++;
8648 	  }
8649 
8650       /* Sort symbol by name.  */
8651       qsort (symtable1, count1, sizeof (struct elf_symbol),
8652 	     elf_sym_name_compare);
8653       qsort (symtable2, count1, sizeof (struct elf_symbol),
8654 	     elf_sym_name_compare);
8655 
8656       for (i = 0; i < count1; i++)
8657 	/* Two symbols must have the same binding, type and name.  */
8658 	if (symtable1 [i].u.ssym->st_info != symtable2 [i].u.ssym->st_info
8659 	    || symtable1 [i].u.ssym->st_other != symtable2 [i].u.ssym->st_other
8660 	    || strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
8661 	  goto done;
8662 
8663       result = true;
8664       goto done;
8665     }
8666 
8667   symtable1 = (struct elf_symbol *)
8668       bfd_malloc (symcount1 * sizeof (struct elf_symbol));
8669   symtable2 = (struct elf_symbol *)
8670       bfd_malloc (symcount2 * sizeof (struct elf_symbol));
8671   if (symtable1 == NULL || symtable2 == NULL)
8672     goto done;
8673 
8674   /* Count definitions in the section.  */
8675   count1 = 0;
8676   for (isym = isymbuf1, isymend = isym + symcount1; isym < isymend; isym++)
8677     if (isym->st_shndx == shndx1
8678 	&& (!ignore_section_symbol_p
8679 	    || ELF_ST_TYPE (isym->st_info) != STT_SECTION))
8680       symtable1[count1++].u.isym = isym;
8681 
8682   count2 = 0;
8683   for (isym = isymbuf2, isymend = isym + symcount2; isym < isymend; isym++)
8684     if (isym->st_shndx == shndx2
8685 	&& (!ignore_section_symbol_p
8686 	    || ELF_ST_TYPE (isym->st_info) != STT_SECTION))
8687       symtable2[count2++].u.isym = isym;
8688 
8689   if (count1 == 0 || count2 == 0 || count1 != count2)
8690     goto done;
8691 
8692   for (i = 0; i < count1; i++)
8693     symtable1[i].name
8694       = bfd_elf_string_from_elf_section (bfd1, hdr1->sh_link,
8695 					 symtable1[i].u.isym->st_name);
8696 
8697   for (i = 0; i < count2; i++)
8698     symtable2[i].name
8699       = bfd_elf_string_from_elf_section (bfd2, hdr2->sh_link,
8700 					 symtable2[i].u.isym->st_name);
8701 
8702   /* Sort symbol by name.  */
8703   qsort (symtable1, count1, sizeof (struct elf_symbol),
8704 	 elf_sym_name_compare);
8705   qsort (symtable2, count1, sizeof (struct elf_symbol),
8706 	 elf_sym_name_compare);
8707 
8708   for (i = 0; i < count1; i++)
8709     /* Two symbols must have the same binding, type and name.  */
8710     if (symtable1 [i].u.isym->st_info != symtable2 [i].u.isym->st_info
8711 	|| symtable1 [i].u.isym->st_other != symtable2 [i].u.isym->st_other
8712 	|| strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
8713       goto done;
8714 
8715   result = true;
8716 
8717  done:
8718   free (symtable1);
8719   free (symtable2);
8720   free (isymbuf1);
8721   free (isymbuf2);
8722 
8723   return result;
8724 }
8725 
8726 /* Return TRUE if 2 section types are compatible.  */
8727 
8728 bool
_bfd_elf_match_sections_by_type(bfd * abfd,const asection * asec,bfd * bbfd,const asection * bsec)8729 _bfd_elf_match_sections_by_type (bfd *abfd, const asection *asec,
8730 				 bfd *bbfd, const asection *bsec)
8731 {
8732   if (asec == NULL
8733       || bsec == NULL
8734       || abfd->xvec->flavour != bfd_target_elf_flavour
8735       || bbfd->xvec->flavour != bfd_target_elf_flavour)
8736     return true;
8737 
8738   return elf_section_type (asec) == elf_section_type (bsec);
8739 }
8740 
8741 /* Final phase of ELF linker.  */
8742 
8743 /* A structure we use to avoid passing large numbers of arguments.  */
8744 
8745 struct elf_final_link_info
8746 {
8747   /* General link information.  */
8748   struct bfd_link_info *info;
8749   /* Output BFD.  */
8750   bfd *output_bfd;
8751   /* Symbol string table.  */
8752   struct elf_strtab_hash *symstrtab;
8753   /* .hash section.  */
8754   asection *hash_sec;
8755   /* symbol version section (.gnu.version).  */
8756   asection *symver_sec;
8757   /* Buffer large enough to hold contents of any section.  */
8758   bfd_byte *contents;
8759   /* Buffer large enough to hold external relocs of any section.  */
8760   void *external_relocs;
8761   /* Buffer large enough to hold internal relocs of any section.  */
8762   Elf_Internal_Rela *internal_relocs;
8763   /* Buffer large enough to hold external local symbols of any input
8764      BFD.  */
8765   bfd_byte *external_syms;
8766   /* And a buffer for symbol section indices.  */
8767   Elf_External_Sym_Shndx *locsym_shndx;
8768   /* Buffer large enough to hold internal local symbols of any input
8769      BFD.  */
8770   Elf_Internal_Sym *internal_syms;
8771   /* Array large enough to hold a symbol index for each local symbol
8772      of any input BFD.  */
8773   long *indices;
8774   /* Array large enough to hold a section pointer for each local
8775      symbol of any input BFD.  */
8776   asection **sections;
8777   /* Buffer for SHT_SYMTAB_SHNDX section.  */
8778   Elf_External_Sym_Shndx *symshndxbuf;
8779   /* Number of STT_FILE syms seen.  */
8780   size_t filesym_count;
8781   /* Local symbol hash table.  */
8782   struct bfd_hash_table local_hash_table;
8783 };
8784 
8785 struct local_hash_entry
8786 {
8787   /* Base hash table entry structure.  */
8788   struct bfd_hash_entry root;
8789   /* Size of the local symbol name.  */
8790   size_t size;
8791   /* Number of the duplicated local symbol names.  */
8792   long count;
8793 };
8794 
8795 /* Create an entry in the local symbol hash table.  */
8796 
8797 static struct bfd_hash_entry *
local_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)8798 local_hash_newfunc (struct bfd_hash_entry *entry,
8799 		    struct bfd_hash_table *table,
8800 		    const char *string)
8801 {
8802 
8803   /* Allocate the structure if it has not already been allocated by a
8804      subclass.  */
8805   if (entry == NULL)
8806     {
8807       entry = bfd_hash_allocate (table,
8808 				 sizeof (struct local_hash_entry));
8809       if (entry == NULL)
8810         return entry;
8811     }
8812 
8813   /* Call the allocation method of the superclass.  */
8814   entry = bfd_hash_newfunc (entry, table, string);
8815   if (entry != NULL)
8816     {
8817       ((struct local_hash_entry *) entry)->count = 0;
8818       ((struct local_hash_entry *) entry)->size = 0;
8819     }
8820 
8821   return entry;
8822 }
8823 
8824 /* This struct is used to pass information to elf_link_output_extsym.  */
8825 
8826 struct elf_outext_info
8827 {
8828   bool failed;
8829   bool localsyms;
8830   bool file_sym_done;
8831   struct elf_final_link_info *flinfo;
8832 };
8833 
8834 
8835 /* Support for evaluating a complex relocation.
8836 
8837    Complex relocations are generalized, self-describing relocations.  The
8838    implementation of them consists of two parts: complex symbols, and the
8839    relocations themselves.
8840 
8841    The relocations use a reserved elf-wide relocation type code (R_RELC
8842    external / BFD_RELOC_RELC internal) and an encoding of relocation field
8843    information (start bit, end bit, word width, etc) into the addend.  This
8844    information is extracted from CGEN-generated operand tables within gas.
8845 
8846    Complex symbols are mangled symbols (STT_RELC external / BSF_RELC
8847    internal) representing prefix-notation expressions, including but not
8848    limited to those sorts of expressions normally encoded as addends in the
8849    addend field.  The symbol mangling format is:
8850 
8851    <node> := <literal>
8852 	  |  <unary-operator> ':' <node>
8853 	  |  <binary-operator> ':' <node> ':' <node>
8854 	  ;
8855 
8856    <literal> := 's' <digits=N> ':' <N character symbol name>
8857 	     |  'S' <digits=N> ':' <N character section name>
8858 	     |  '#' <hexdigits>
8859 	     ;
8860 
8861    <binary-operator> := as in C
8862    <unary-operator> := as in C, plus "0-" for unambiguous negation.  */
8863 
8864 static void
set_symbol_value(bfd * bfd_with_globals,Elf_Internal_Sym * isymbuf,size_t locsymcount,size_t symidx,bfd_vma val)8865 set_symbol_value (bfd *bfd_with_globals,
8866 		  Elf_Internal_Sym *isymbuf,
8867 		  size_t locsymcount,
8868 		  size_t symidx,
8869 		  bfd_vma val)
8870 {
8871   struct elf_link_hash_entry **sym_hashes;
8872   struct elf_link_hash_entry *h;
8873   size_t extsymoff = locsymcount;
8874 
8875   if (symidx < locsymcount)
8876     {
8877       Elf_Internal_Sym *sym;
8878 
8879       sym = isymbuf + symidx;
8880       if (ELF_ST_BIND (sym->st_info) == STB_LOCAL)
8881 	{
8882 	  /* It is a local symbol: move it to the
8883 	     "absolute" section and give it a value.  */
8884 	  sym->st_shndx = SHN_ABS;
8885 	  sym->st_value = val;
8886 	  return;
8887 	}
8888       BFD_ASSERT (elf_bad_symtab (bfd_with_globals));
8889       extsymoff = 0;
8890     }
8891 
8892   /* It is a global symbol: set its link type
8893      to "defined" and give it a value.  */
8894 
8895   sym_hashes = elf_sym_hashes (bfd_with_globals);
8896   h = sym_hashes [symidx - extsymoff];
8897   while (h->root.type == bfd_link_hash_indirect
8898 	 || h->root.type == bfd_link_hash_warning)
8899     h = (struct elf_link_hash_entry *) h->root.u.i.link;
8900   h->root.type = bfd_link_hash_defined;
8901   h->root.u.def.value = val;
8902   h->root.u.def.section = bfd_abs_section_ptr;
8903 }
8904 
8905 static bool
resolve_symbol(const char * name,bfd * input_bfd,struct elf_final_link_info * flinfo,bfd_vma * result,Elf_Internal_Sym * isymbuf,size_t locsymcount)8906 resolve_symbol (const char *name,
8907 		bfd *input_bfd,
8908 		struct elf_final_link_info *flinfo,
8909 		bfd_vma *result,
8910 		Elf_Internal_Sym *isymbuf,
8911 		size_t locsymcount)
8912 {
8913   Elf_Internal_Sym *sym;
8914   struct bfd_link_hash_entry *global_entry;
8915   const char *candidate = NULL;
8916   Elf_Internal_Shdr *symtab_hdr;
8917   size_t i;
8918 
8919   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
8920 
8921   for (i = 0; i < locsymcount; ++ i)
8922     {
8923       sym = isymbuf + i;
8924 
8925       if (ELF_ST_BIND (sym->st_info) != STB_LOCAL)
8926 	continue;
8927 
8928       candidate = bfd_elf_string_from_elf_section (input_bfd,
8929 						   symtab_hdr->sh_link,
8930 						   sym->st_name);
8931 #ifdef DEBUG
8932       printf ("Comparing string: '%s' vs. '%s' = 0x%lx\n",
8933 	      name, candidate, (unsigned long) sym->st_value);
8934 #endif
8935       if (candidate && strcmp (candidate, name) == 0)
8936 	{
8937 	  asection *sec = flinfo->sections [i];
8938 
8939 	  *result = _bfd_elf_rel_local_sym (input_bfd, sym, &sec, 0);
8940 	  *result += sec->output_offset + sec->output_section->vma;
8941 #ifdef DEBUG
8942 	  printf ("Found symbol with value %8.8lx\n",
8943 		  (unsigned long) *result);
8944 #endif
8945 	  return true;
8946 	}
8947     }
8948 
8949   /* Hmm, haven't found it yet. perhaps it is a global.  */
8950   global_entry = bfd_link_hash_lookup (flinfo->info->hash, name,
8951 				       false, false, true);
8952   if (!global_entry)
8953     return false;
8954 
8955   if (global_entry->type == bfd_link_hash_defined
8956       || global_entry->type == bfd_link_hash_defweak)
8957     {
8958       *result = (global_entry->u.def.value
8959 		 + global_entry->u.def.section->output_section->vma
8960 		 + global_entry->u.def.section->output_offset);
8961 #ifdef DEBUG
8962       printf ("Found GLOBAL symbol '%s' with value %8.8lx\n",
8963 	      global_entry->root.string, (unsigned long) *result);
8964 #endif
8965       return true;
8966     }
8967 
8968   return false;
8969 }
8970 
8971 /* Looks up NAME in SECTIONS.  If found sets RESULT to NAME's address (in
8972    bytes) and returns TRUE, otherwise returns FALSE.  Accepts pseudo-section
8973    names like "foo.end" which is the end address of section "foo".  */
8974 
8975 static bool
resolve_section(const char * name,asection * sections,bfd_vma * result,bfd * abfd)8976 resolve_section (const char *name,
8977 		 asection *sections,
8978 		 bfd_vma *result,
8979 		 bfd * abfd)
8980 {
8981   asection *curr;
8982   unsigned int len;
8983 
8984   for (curr = sections; curr; curr = curr->next)
8985     if (strcmp (curr->name, name) == 0)
8986       {
8987 	*result = curr->vma;
8988 	return true;
8989       }
8990 
8991   /* Hmm. still haven't found it. try pseudo-section names.  */
8992   /* FIXME: This could be coded more efficiently...  */
8993   for (curr = sections; curr; curr = curr->next)
8994     {
8995       len = strlen (curr->name);
8996       if (len > strlen (name))
8997 	continue;
8998 
8999       if (strncmp (curr->name, name, len) == 0)
9000 	{
9001 	  if (startswith (name + len, ".end"))
9002 	    {
9003 	      *result = (curr->vma
9004 			 + curr->size / bfd_octets_per_byte (abfd, curr));
9005 	      return true;
9006 	    }
9007 
9008 	  /* Insert more pseudo-section names here, if you like.  */
9009 	}
9010     }
9011 
9012   return false;
9013 }
9014 
9015 static void
undefined_reference(const char * reftype,const char * name)9016 undefined_reference (const char *reftype, const char *name)
9017 {
9018   /* xgettext:c-format */
9019   _bfd_error_handler (_("undefined %s reference in complex symbol: %s"),
9020 		      reftype, name);
9021   bfd_set_error (bfd_error_bad_value);
9022 }
9023 
9024 static bool
eval_symbol(bfd_vma * result,const char ** symp,bfd * input_bfd,struct elf_final_link_info * flinfo,bfd_vma dot,Elf_Internal_Sym * isymbuf,size_t locsymcount,int signed_p)9025 eval_symbol (bfd_vma *result,
9026 	     const char **symp,
9027 	     bfd *input_bfd,
9028 	     struct elf_final_link_info *flinfo,
9029 	     bfd_vma dot,
9030 	     Elf_Internal_Sym *isymbuf,
9031 	     size_t locsymcount,
9032 	     int signed_p)
9033 {
9034   size_t len;
9035   size_t symlen;
9036   bfd_vma a;
9037   bfd_vma b;
9038   char symbuf[4096];
9039   const char *sym = *symp;
9040   const char *symend;
9041   bool symbol_is_section = false;
9042 
9043   len = strlen (sym);
9044   symend = sym + len;
9045 
9046   if (len < 1 || len > sizeof (symbuf))
9047     {
9048       bfd_set_error (bfd_error_invalid_operation);
9049       return false;
9050     }
9051 
9052   switch (* sym)
9053     {
9054     case '.':
9055       *result = dot;
9056       *symp = sym + 1;
9057       return true;
9058 
9059     case '#':
9060       ++sym;
9061       *result = strtoul (sym, (char **) symp, 16);
9062       return true;
9063 
9064     case 'S':
9065       symbol_is_section = true;
9066       /* Fall through.  */
9067     case 's':
9068       ++sym;
9069       symlen = strtol (sym, (char **) symp, 10);
9070       sym = *symp + 1; /* Skip the trailing ':'.  */
9071 
9072       if (symend < sym || symlen + 1 > sizeof (symbuf))
9073 	{
9074 	  bfd_set_error (bfd_error_invalid_operation);
9075 	  return false;
9076 	}
9077 
9078       memcpy (symbuf, sym, symlen);
9079       symbuf[symlen] = '\0';
9080       *symp = sym + symlen;
9081 
9082       /* Is it always possible, with complex symbols, that gas "mis-guessed"
9083 	 the symbol as a section, or vice-versa. so we're pretty liberal in our
9084 	 interpretation here; section means "try section first", not "must be a
9085 	 section", and likewise with symbol.  */
9086 
9087       if (symbol_is_section)
9088 	{
9089 	  if (!resolve_section (symbuf, flinfo->output_bfd->sections, result, input_bfd)
9090 	      && !resolve_symbol (symbuf, input_bfd, flinfo, result,
9091 				  isymbuf, locsymcount))
9092 	    {
9093 	      undefined_reference ("section", symbuf);
9094 	      return false;
9095 	    }
9096 	}
9097       else
9098 	{
9099 	  if (!resolve_symbol (symbuf, input_bfd, flinfo, result,
9100 			       isymbuf, locsymcount)
9101 	      && !resolve_section (symbuf, flinfo->output_bfd->sections,
9102 				   result, input_bfd))
9103 	    {
9104 	      undefined_reference ("symbol", symbuf);
9105 	      return false;
9106 	    }
9107 	}
9108 
9109       return true;
9110 
9111       /* All that remains are operators.  */
9112 
9113 #define UNARY_OP(op)						\
9114   if (startswith (sym, #op))					\
9115     {								\
9116       sym += strlen (#op);					\
9117       if (*sym == ':')						\
9118 	++sym;							\
9119       *symp = sym;						\
9120       if (!eval_symbol (&a, symp, input_bfd, flinfo, dot,	\
9121 			isymbuf, locsymcount, signed_p))	\
9122 	return false;						\
9123       if (signed_p)						\
9124 	*result = op ((bfd_signed_vma) a);			\
9125       else							\
9126 	*result = op a;						\
9127       return true;						\
9128     }
9129 
9130 #define BINARY_OP_HEAD(op)					\
9131   if (startswith (sym, #op))					\
9132     {								\
9133       sym += strlen (#op);					\
9134       if (*sym == ':')						\
9135 	++sym;							\
9136       *symp = sym;						\
9137       if (!eval_symbol (&a, symp, input_bfd, flinfo, dot,	\
9138 			isymbuf, locsymcount, signed_p))	\
9139 	return false;						\
9140       ++*symp;							\
9141       if (!eval_symbol (&b, symp, input_bfd, flinfo, dot,	\
9142 			isymbuf, locsymcount, signed_p))	\
9143 	return false;
9144 #define BINARY_OP_TAIL(op)					\
9145       if (signed_p)						\
9146 	*result = ((bfd_signed_vma) a) op ((bfd_signed_vma) b);	\
9147       else							\
9148 	*result = a op b;					\
9149       return true;						\
9150     }
9151 #define BINARY_OP(op) BINARY_OP_HEAD(op) BINARY_OP_TAIL(op)
9152 
9153     default:
9154       UNARY_OP  (0-);
9155       BINARY_OP_HEAD (<<);
9156       if (b >= sizeof (a) * CHAR_BIT)
9157 	{
9158 	  *result = 0;
9159 	  return true;
9160 	}
9161       signed_p = 0;
9162       BINARY_OP_TAIL (<<);
9163       BINARY_OP_HEAD (>>);
9164       if (b >= sizeof (a) * CHAR_BIT)
9165 	{
9166 	  *result = signed_p && (bfd_signed_vma) a < 0 ? -1 : 0;
9167 	  return true;
9168 	}
9169       BINARY_OP_TAIL (>>);
9170       BINARY_OP (==);
9171       BINARY_OP (!=);
9172       BINARY_OP (<=);
9173       BINARY_OP (>=);
9174       BINARY_OP (&&);
9175       BINARY_OP (||);
9176       UNARY_OP  (~);
9177       UNARY_OP  (!);
9178       BINARY_OP (*);
9179       BINARY_OP_HEAD (/);
9180       if (b == 0)
9181 	{
9182 	  _bfd_error_handler (_("division by zero"));
9183 	  bfd_set_error (bfd_error_bad_value);
9184 	  return false;
9185 	}
9186       BINARY_OP_TAIL (/);
9187       BINARY_OP_HEAD (%);
9188       if (b == 0)
9189 	{
9190 	  _bfd_error_handler (_("division by zero"));
9191 	  bfd_set_error (bfd_error_bad_value);
9192 	  return false;
9193 	}
9194       BINARY_OP_TAIL (%);
9195       BINARY_OP (^);
9196       BINARY_OP (|);
9197       BINARY_OP (&);
9198       BINARY_OP (+);
9199       BINARY_OP (-);
9200       BINARY_OP (<);
9201       BINARY_OP (>);
9202 #undef UNARY_OP
9203 #undef BINARY_OP
9204       _bfd_error_handler (_("unknown operator '%c' in complex symbol"), * sym);
9205       bfd_set_error (bfd_error_invalid_operation);
9206       return false;
9207     }
9208 }
9209 
9210 static void
put_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_vma x,bfd_byte * location)9211 put_value (bfd_vma size,
9212 	   unsigned long chunksz,
9213 	   bfd *input_bfd,
9214 	   bfd_vma x,
9215 	   bfd_byte *location)
9216 {
9217   location += (size - chunksz);
9218 
9219   for (; size; size -= chunksz, location -= chunksz)
9220     {
9221       switch (chunksz)
9222 	{
9223 	case 1:
9224 	  bfd_put_8 (input_bfd, x, location);
9225 	  x >>= 8;
9226 	  break;
9227 	case 2:
9228 	  bfd_put_16 (input_bfd, x, location);
9229 	  x >>= 16;
9230 	  break;
9231 	case 4:
9232 	  bfd_put_32 (input_bfd, x, location);
9233 	  /* Computed this way because x >>= 32 is undefined if x is a 32-bit value.  */
9234 	  x >>= 16;
9235 	  x >>= 16;
9236 	  break;
9237 #ifdef BFD64
9238 	case 8:
9239 	  bfd_put_64 (input_bfd, x, location);
9240 	  /* Computed this way because x >>= 64 is undefined if x is a 64-bit value.  */
9241 	  x >>= 32;
9242 	  x >>= 32;
9243 	  break;
9244 #endif
9245 	default:
9246 	  abort ();
9247 	  break;
9248 	}
9249     }
9250 }
9251 
9252 static bfd_vma
get_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_byte * location)9253 get_value (bfd_vma size,
9254 	   unsigned long chunksz,
9255 	   bfd *input_bfd,
9256 	   bfd_byte *location)
9257 {
9258   int shift;
9259   bfd_vma x = 0;
9260 
9261   /* Sanity checks.  */
9262   BFD_ASSERT (chunksz <= sizeof (x)
9263 	      && size >= chunksz
9264 	      && chunksz != 0
9265 	      && (size % chunksz) == 0
9266 	      && input_bfd != NULL
9267 	      && location != NULL);
9268 
9269   if (chunksz == sizeof (x))
9270     {
9271       BFD_ASSERT (size == chunksz);
9272 
9273       /* Make sure that we do not perform an undefined shift operation.
9274 	 We know that size == chunksz so there will only be one iteration
9275 	 of the loop below.  */
9276       shift = 0;
9277     }
9278   else
9279     shift = 8 * chunksz;
9280 
9281   for (; size; size -= chunksz, location += chunksz)
9282     {
9283       switch (chunksz)
9284 	{
9285 	case 1:
9286 	  x = (x << shift) | bfd_get_8 (input_bfd, location);
9287 	  break;
9288 	case 2:
9289 	  x = (x << shift) | bfd_get_16 (input_bfd, location);
9290 	  break;
9291 	case 4:
9292 	  x = (x << shift) | bfd_get_32 (input_bfd, location);
9293 	  break;
9294 #ifdef BFD64
9295 	case 8:
9296 	  x = (x << shift) | bfd_get_64 (input_bfd, location);
9297 	  break;
9298 #endif
9299 	default:
9300 	  abort ();
9301 	}
9302     }
9303   return x;
9304 }
9305 
9306 static void
decode_complex_addend(unsigned long * start,unsigned long * oplen,unsigned long * len,unsigned long * wordsz,unsigned long * chunksz,unsigned long * lsb0_p,unsigned long * signed_p,unsigned long * trunc_p,unsigned long encoded)9307 decode_complex_addend (unsigned long *start,   /* in bits */
9308 		       unsigned long *oplen,   /* in bits */
9309 		       unsigned long *len,     /* in bits */
9310 		       unsigned long *wordsz,  /* in bytes */
9311 		       unsigned long *chunksz, /* in bytes */
9312 		       unsigned long *lsb0_p,
9313 		       unsigned long *signed_p,
9314 		       unsigned long *trunc_p,
9315 		       unsigned long encoded)
9316 {
9317   * start     =	 encoded	& 0x3F;
9318   * len	      = (encoded >>  6) & 0x3F;
9319   * oplen     = (encoded >> 12) & 0x3F;
9320   * wordsz    = (encoded >> 18) & 0xF;
9321   * chunksz   = (encoded >> 22) & 0xF;
9322   * lsb0_p    = (encoded >> 27) & 1;
9323   * signed_p  = (encoded >> 28) & 1;
9324   * trunc_p   = (encoded >> 29) & 1;
9325 }
9326 
9327 bfd_reloc_status_type
bfd_elf_perform_complex_relocation(bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * rel,bfd_vma relocation)9328 bfd_elf_perform_complex_relocation (bfd *input_bfd,
9329 				    asection *input_section,
9330 				    bfd_byte *contents,
9331 				    Elf_Internal_Rela *rel,
9332 				    bfd_vma relocation)
9333 {
9334   bfd_vma shift, x, mask;
9335   unsigned long start, oplen, len, wordsz, chunksz, lsb0_p, signed_p, trunc_p;
9336   bfd_reloc_status_type r;
9337   bfd_size_type octets;
9338 
9339   /*  Perform this reloc, since it is complex.
9340       (this is not to say that it necessarily refers to a complex
9341       symbol; merely that it is a self-describing CGEN based reloc.
9342       i.e. the addend has the complete reloc information (bit start, end,
9343       word size, etc) encoded within it.).  */
9344 
9345   decode_complex_addend (&start, &oplen, &len, &wordsz,
9346 			 &chunksz, &lsb0_p, &signed_p,
9347 			 &trunc_p, rel->r_addend);
9348 
9349   mask = (((1L << (len - 1)) - 1) << 1) | 1;
9350 
9351   if (lsb0_p)
9352     shift = (start + 1) - len;
9353   else
9354     shift = (8 * wordsz) - (start + len);
9355 
9356   octets = rel->r_offset * bfd_octets_per_byte (input_bfd, input_section);
9357   x = get_value (wordsz, chunksz, input_bfd, contents + octets);
9358 
9359 #ifdef DEBUG
9360   printf ("Doing complex reloc: "
9361 	  "lsb0? %ld, signed? %ld, trunc? %ld, wordsz %ld, "
9362 	  "chunksz %ld, start %ld, len %ld, oplen %ld\n"
9363 	  "    dest: %8.8lx, mask: %8.8lx, reloc: %8.8lx\n",
9364 	  lsb0_p, signed_p, trunc_p, wordsz, chunksz, start, len,
9365 	  oplen, (unsigned long) x, (unsigned long) mask,
9366 	  (unsigned long) relocation);
9367 #endif
9368 
9369   r = bfd_reloc_ok;
9370   if (! trunc_p)
9371     /* Now do an overflow check.  */
9372     r = bfd_check_overflow ((signed_p
9373 			     ? complain_overflow_signed
9374 			     : complain_overflow_unsigned),
9375 			    len, 0, (8 * wordsz),
9376 			    relocation);
9377 
9378   /* Do the deed.  */
9379   x = (x & ~(mask << shift)) | ((relocation & mask) << shift);
9380 
9381 #ifdef DEBUG
9382   printf ("           relocation: %8.8lx\n"
9383 	  "         shifted mask: %8.8lx\n"
9384 	  " shifted/masked reloc: %8.8lx\n"
9385 	  "               result: %8.8lx\n",
9386 	  (unsigned long) relocation, (unsigned long) (mask << shift),
9387 	  (unsigned long) ((relocation & mask) << shift), (unsigned long) x);
9388 #endif
9389   put_value (wordsz, chunksz, input_bfd, x, contents + octets);
9390   return r;
9391 }
9392 
9393 /* Functions to read r_offset from external (target order) reloc
9394    entry.  Faster than bfd_getl32 et al, because we let the compiler
9395    know the value is aligned.  */
9396 
9397 static bfd_vma
ext32l_r_offset(const void * p)9398 ext32l_r_offset (const void *p)
9399 {
9400   union aligned32
9401   {
9402     uint32_t v;
9403     unsigned char c[4];
9404   };
9405   const union aligned32 *a
9406     = (const union aligned32 *) &((const Elf32_External_Rel *) p)->r_offset;
9407 
9408   uint32_t aval = (  (uint32_t) a->c[0]
9409 		   | (uint32_t) a->c[1] << 8
9410 		   | (uint32_t) a->c[2] << 16
9411 		   | (uint32_t) a->c[3] << 24);
9412   return aval;
9413 }
9414 
9415 static bfd_vma
ext32b_r_offset(const void * p)9416 ext32b_r_offset (const void *p)
9417 {
9418   union aligned32
9419   {
9420     uint32_t v;
9421     unsigned char c[4];
9422   };
9423   const union aligned32 *a
9424     = (const union aligned32 *) &((const Elf32_External_Rel *) p)->r_offset;
9425 
9426   uint32_t aval = (  (uint32_t) a->c[0] << 24
9427 		   | (uint32_t) a->c[1] << 16
9428 		   | (uint32_t) a->c[2] << 8
9429 		   | (uint32_t) a->c[3]);
9430   return aval;
9431 }
9432 
9433 static bfd_vma
ext64l_r_offset(const void * p)9434 ext64l_r_offset (const void *p)
9435 {
9436   union aligned64
9437   {
9438     uint64_t v;
9439     unsigned char c[8];
9440   };
9441   const union aligned64 *a
9442     = (const union aligned64 *) &((const Elf64_External_Rel *) p)->r_offset;
9443 
9444   uint64_t aval = (  (uint64_t) a->c[0]
9445 		   | (uint64_t) a->c[1] << 8
9446 		   | (uint64_t) a->c[2] << 16
9447 		   | (uint64_t) a->c[3] << 24
9448 		   | (uint64_t) a->c[4] << 32
9449 		   | (uint64_t) a->c[5] << 40
9450 		   | (uint64_t) a->c[6] << 48
9451 		   | (uint64_t) a->c[7] << 56);
9452   return aval;
9453 }
9454 
9455 static bfd_vma
ext64b_r_offset(const void * p)9456 ext64b_r_offset (const void *p)
9457 {
9458   union aligned64
9459   {
9460     uint64_t v;
9461     unsigned char c[8];
9462   };
9463   const union aligned64 *a
9464     = (const union aligned64 *) &((const Elf64_External_Rel *) p)->r_offset;
9465 
9466   uint64_t aval = (  (uint64_t) a->c[0] << 56
9467 		   | (uint64_t) a->c[1] << 48
9468 		   | (uint64_t) a->c[2] << 40
9469 		   | (uint64_t) a->c[3] << 32
9470 		   | (uint64_t) a->c[4] << 24
9471 		   | (uint64_t) a->c[5] << 16
9472 		   | (uint64_t) a->c[6] << 8
9473 		   | (uint64_t) a->c[7]);
9474   return aval;
9475 }
9476 
9477 /* When performing a relocatable link, the input relocations are
9478    preserved.  But, if they reference global symbols, the indices
9479    referenced must be updated.  Update all the relocations found in
9480    RELDATA.  */
9481 
9482 static bool
elf_link_adjust_relocs(bfd * abfd,asection * sec,struct bfd_elf_section_reloc_data * reldata,bool sort,struct bfd_link_info * info)9483 elf_link_adjust_relocs (bfd *abfd,
9484 			asection *sec,
9485 			struct bfd_elf_section_reloc_data *reldata,
9486 			bool sort,
9487 			struct bfd_link_info *info)
9488 {
9489   unsigned int i;
9490   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9491   bfd_byte *erela;
9492   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
9493   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
9494   bfd_vma r_type_mask;
9495   int r_sym_shift;
9496   unsigned int count = reldata->count;
9497   struct elf_link_hash_entry **rel_hash = reldata->hashes;
9498 
9499   if (reldata->hdr->sh_entsize == bed->s->sizeof_rel)
9500     {
9501       swap_in = bed->s->swap_reloc_in;
9502       swap_out = bed->s->swap_reloc_out;
9503     }
9504   else if (reldata->hdr->sh_entsize == bed->s->sizeof_rela)
9505     {
9506       swap_in = bed->s->swap_reloca_in;
9507       swap_out = bed->s->swap_reloca_out;
9508     }
9509   else
9510     abort ();
9511 
9512   if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
9513     abort ();
9514 
9515   if (bed->s->arch_size == 32)
9516     {
9517       r_type_mask = 0xff;
9518       r_sym_shift = 8;
9519     }
9520   else
9521     {
9522       r_type_mask = 0xffffffff;
9523       r_sym_shift = 32;
9524     }
9525 
9526   erela = reldata->hdr->contents;
9527   for (i = 0; i < count; i++, rel_hash++, erela += reldata->hdr->sh_entsize)
9528     {
9529       Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
9530       unsigned int j;
9531 
9532       if (*rel_hash == NULL)
9533 	continue;
9534 
9535       if ((*rel_hash)->indx == -2
9536 	  && info->gc_sections
9537 	  && ! info->gc_keep_exported)
9538 	{
9539 	  /* PR 21524: Let the user know if a symbol was removed by garbage collection.  */
9540 	  _bfd_error_handler (_("%pB:%pA: error: relocation references symbol %s which was removed by garbage collection"),
9541 			      abfd, sec,
9542 			      (*rel_hash)->root.root.string);
9543 	  _bfd_error_handler (_("%pB:%pA: error: try relinking with --gc-keep-exported enabled"),
9544 			      abfd, sec);
9545 	  bfd_set_error (bfd_error_invalid_operation);
9546 	  return false;
9547 	}
9548       BFD_ASSERT ((*rel_hash)->indx >= 0);
9549 
9550       (*swap_in) (abfd, erela, irela);
9551       for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
9552 	irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
9553 			   | (irela[j].r_info & r_type_mask));
9554       (*swap_out) (abfd, irela, erela);
9555     }
9556 
9557   if (bed->elf_backend_update_relocs)
9558     (*bed->elf_backend_update_relocs) (sec, reldata);
9559 
9560   if (sort && count != 0)
9561     {
9562       bfd_vma (*ext_r_off) (const void *);
9563       bfd_vma r_off;
9564       size_t elt_size;
9565       bfd_byte *base, *end, *p, *loc;
9566       bfd_byte *buf = NULL;
9567 
9568       if (bed->s->arch_size == 32)
9569 	{
9570 	  if (abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)
9571 	    ext_r_off = ext32l_r_offset;
9572 	  else if (abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
9573 	    ext_r_off = ext32b_r_offset;
9574 	  else
9575 	    abort ();
9576 	}
9577       else
9578 	{
9579 	  if (abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)
9580 	    ext_r_off = ext64l_r_offset;
9581 	  else if (abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
9582 	    ext_r_off = ext64b_r_offset;
9583 	  else
9584 	    abort ();
9585 	}
9586 
9587       /*  Must use a stable sort here.  A modified insertion sort,
9588 	  since the relocs are mostly sorted already.  */
9589       elt_size = reldata->hdr->sh_entsize;
9590       base = reldata->hdr->contents;
9591       end = base + count * elt_size;
9592       if (elt_size > sizeof (Elf64_External_Rela))
9593 	abort ();
9594 
9595       /* Ensure the first element is lowest.  This acts as a sentinel,
9596 	 speeding the main loop below.  */
9597       r_off = (*ext_r_off) (base);
9598       for (p = loc = base; (p += elt_size) < end; )
9599 	{
9600 	  bfd_vma r_off2 = (*ext_r_off) (p);
9601 	  if (r_off > r_off2)
9602 	    {
9603 	      r_off = r_off2;
9604 	      loc = p;
9605 	    }
9606 	}
9607       if (loc != base)
9608 	{
9609 	  /* Don't just swap *base and *loc as that changes the order
9610 	     of the original base[0] and base[1] if they happen to
9611 	     have the same r_offset.  */
9612 	  bfd_byte onebuf[sizeof (Elf64_External_Rela)];
9613 	  memcpy (onebuf, loc, elt_size);
9614 	  memmove (base + elt_size, base, loc - base);
9615 	  memcpy (base, onebuf, elt_size);
9616 	}
9617 
9618       for (p = base + elt_size; (p += elt_size) < end; )
9619 	{
9620 	  /* base to p is sorted, *p is next to insert.  */
9621 	  r_off = (*ext_r_off) (p);
9622 	  /* Search the sorted region for location to insert.  */
9623 	  loc = p - elt_size;
9624 	  while (r_off < (*ext_r_off) (loc))
9625 	    loc -= elt_size;
9626 	  loc += elt_size;
9627 	  if (loc != p)
9628 	    {
9629 	      /* Chances are there is a run of relocs to insert here,
9630 		 from one of more input files.  Files are not always
9631 		 linked in order due to the way elf_link_input_bfd is
9632 		 called.  See pr17666.  */
9633 	      size_t sortlen = p - loc;
9634 	      bfd_vma r_off2 = (*ext_r_off) (loc);
9635 	      size_t runlen = elt_size;
9636 	      bfd_vma r_off_runend = r_off;
9637 	      bfd_vma r_off_runend_next;
9638 	      size_t buf_size = 96 * 1024;
9639 	      while (p + runlen < end
9640 		     && (sortlen <= buf_size
9641 			 || runlen + elt_size <= buf_size)
9642 		     /* run must not break the ordering of base..loc+1 */
9643 		     && r_off2 > (r_off_runend_next = (*ext_r_off) (p + runlen))
9644 		     /* run must be already sorted */
9645 		     && r_off_runend_next >= r_off_runend)
9646 		{
9647 		  runlen += elt_size;
9648 		  r_off_runend = r_off_runend_next;
9649 		}
9650 	      if (buf == NULL)
9651 		{
9652 		  buf = bfd_malloc (buf_size);
9653 		  if (buf == NULL)
9654 		    return false;
9655 		}
9656 	      if (runlen < sortlen)
9657 		{
9658 		  memcpy (buf, p, runlen);
9659 		  memmove (loc + runlen, loc, sortlen);
9660 		  memcpy (loc, buf, runlen);
9661 		}
9662 	      else
9663 		{
9664 		  memcpy (buf, loc, sortlen);
9665 		  memmove (loc, p, runlen);
9666 		  memcpy (loc + runlen, buf, sortlen);
9667 		}
9668 	      p += runlen - elt_size;
9669 	    }
9670 	}
9671       /* Hashes are no longer valid.  */
9672       free (reldata->hashes);
9673       reldata->hashes = NULL;
9674       free (buf);
9675     }
9676   return true;
9677 }
9678 
9679 struct elf_link_sort_rela
9680 {
9681   union {
9682     bfd_vma offset;
9683     bfd_vma sym_mask;
9684   } u;
9685   enum elf_reloc_type_class type;
9686   /* We use this as an array of size int_rels_per_ext_rel.  */
9687   Elf_Internal_Rela rela[1];
9688 };
9689 
9690 /* qsort stability here and for cmp2 is only an issue if multiple
9691    dynamic relocations are emitted at the same address.  But targets
9692    that apply a series of dynamic relocations each operating on the
9693    result of the prior relocation can't use -z combreloc as
9694    implemented anyway.  Such schemes tend to be broken by sorting on
9695    symbol index.  That leaves dynamic NONE relocs as the only other
9696    case where ld might emit multiple relocs at the same address, and
9697    those are only emitted due to target bugs.  */
9698 
9699 static int
elf_link_sort_cmp1(const void * A,const void * B)9700 elf_link_sort_cmp1 (const void *A, const void *B)
9701 {
9702   const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
9703   const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
9704   int relativea, relativeb;
9705 
9706   relativea = a->type == reloc_class_relative;
9707   relativeb = b->type == reloc_class_relative;
9708 
9709   if (relativea < relativeb)
9710     return 1;
9711   if (relativea > relativeb)
9712     return -1;
9713   if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
9714     return -1;
9715   if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
9716     return 1;
9717   if (a->rela->r_offset < b->rela->r_offset)
9718     return -1;
9719   if (a->rela->r_offset > b->rela->r_offset)
9720     return 1;
9721   return 0;
9722 }
9723 
9724 static int
elf_link_sort_cmp2(const void * A,const void * B)9725 elf_link_sort_cmp2 (const void *A, const void *B)
9726 {
9727   const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
9728   const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
9729 
9730   if (a->type < b->type)
9731     return -1;
9732   if (a->type > b->type)
9733     return 1;
9734   if (a->u.offset < b->u.offset)
9735     return -1;
9736   if (a->u.offset > b->u.offset)
9737     return 1;
9738   if (a->rela->r_offset < b->rela->r_offset)
9739     return -1;
9740   if (a->rela->r_offset > b->rela->r_offset)
9741     return 1;
9742   return 0;
9743 }
9744 
9745 static size_t
elf_link_sort_relocs(bfd * abfd,struct bfd_link_info * info,asection ** psec)9746 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
9747 {
9748   asection *dynamic_relocs;
9749   asection *rela_dyn;
9750   asection *rel_dyn;
9751   bfd_size_type count, size;
9752   size_t i, ret, sort_elt, ext_size;
9753   bfd_byte *sort, *s_non_relative, *p;
9754   struct elf_link_sort_rela *sq;
9755   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9756   int i2e = bed->s->int_rels_per_ext_rel;
9757   unsigned int opb = bfd_octets_per_byte (abfd, NULL);
9758   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
9759   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
9760   struct bfd_link_order *lo;
9761   bfd_vma r_sym_mask;
9762   bool use_rela;
9763 
9764   /* Find a dynamic reloc section.  */
9765   rela_dyn = bfd_get_section_by_name (abfd, ".rela.dyn");
9766   rel_dyn  = bfd_get_section_by_name (abfd, ".rel.dyn");
9767   if (rela_dyn != NULL && rela_dyn->size > 0
9768       && rel_dyn != NULL && rel_dyn->size > 0)
9769     {
9770       bool use_rela_initialised = false;
9771 
9772       /* This is just here to stop gcc from complaining.
9773 	 Its initialization checking code is not perfect.  */
9774       use_rela = true;
9775 
9776       /* Both sections are present.  Examine the sizes
9777 	 of the indirect sections to help us choose.  */
9778       for (lo = rela_dyn->map_head.link_order; lo != NULL; lo = lo->next)
9779 	if (lo->type == bfd_indirect_link_order)
9780 	  {
9781 	    asection *o = lo->u.indirect.section;
9782 
9783 	    if ((o->size % bed->s->sizeof_rela) == 0)
9784 	      {
9785 		if ((o->size % bed->s->sizeof_rel) == 0)
9786 		  /* Section size is divisible by both rel and rela sizes.
9787 		     It is of no help to us.  */
9788 		  ;
9789 		else
9790 		  {
9791 		    /* Section size is only divisible by rela.  */
9792 		    if (use_rela_initialised && !use_rela)
9793 		      {
9794 			_bfd_error_handler (_("%pB: unable to sort relocs - "
9795 					      "they are in more than one size"),
9796 					    abfd);
9797 			bfd_set_error (bfd_error_invalid_operation);
9798 			return 0;
9799 		      }
9800 		    else
9801 		      {
9802 			use_rela = true;
9803 			use_rela_initialised = true;
9804 		      }
9805 		  }
9806 	      }
9807 	    else if ((o->size % bed->s->sizeof_rel) == 0)
9808 	      {
9809 		/* Section size is only divisible by rel.  */
9810 		if (use_rela_initialised && use_rela)
9811 		  {
9812 		    _bfd_error_handler (_("%pB: unable to sort relocs - "
9813 					  "they are in more than one size"),
9814 					abfd);
9815 		    bfd_set_error (bfd_error_invalid_operation);
9816 		    return 0;
9817 		  }
9818 		else
9819 		  {
9820 		    use_rela = false;
9821 		    use_rela_initialised = true;
9822 		  }
9823 	      }
9824 	    else
9825 	      {
9826 		/* The section size is not divisible by either -
9827 		   something is wrong.  */
9828 		_bfd_error_handler (_("%pB: unable to sort relocs - "
9829 				      "they are of an unknown size"), abfd);
9830 		bfd_set_error (bfd_error_invalid_operation);
9831 		return 0;
9832 	      }
9833 	  }
9834 
9835       for (lo = rel_dyn->map_head.link_order; lo != NULL; lo = lo->next)
9836 	if (lo->type == bfd_indirect_link_order)
9837 	  {
9838 	    asection *o = lo->u.indirect.section;
9839 
9840 	    if ((o->size % bed->s->sizeof_rela) == 0)
9841 	      {
9842 		if ((o->size % bed->s->sizeof_rel) == 0)
9843 		  /* Section size is divisible by both rel and rela sizes.
9844 		     It is of no help to us.  */
9845 		  ;
9846 		else
9847 		  {
9848 		    /* Section size is only divisible by rela.  */
9849 		    if (use_rela_initialised && !use_rela)
9850 		      {
9851 			_bfd_error_handler (_("%pB: unable to sort relocs - "
9852 					      "they are in more than one size"),
9853 					    abfd);
9854 			bfd_set_error (bfd_error_invalid_operation);
9855 			return 0;
9856 		      }
9857 		    else
9858 		      {
9859 			use_rela = true;
9860 			use_rela_initialised = true;
9861 		      }
9862 		  }
9863 	      }
9864 	    else if ((o->size % bed->s->sizeof_rel) == 0)
9865 	      {
9866 		/* Section size is only divisible by rel.  */
9867 		if (use_rela_initialised && use_rela)
9868 		  {
9869 		    _bfd_error_handler (_("%pB: unable to sort relocs - "
9870 					  "they are in more than one size"),
9871 					abfd);
9872 		    bfd_set_error (bfd_error_invalid_operation);
9873 		    return 0;
9874 		  }
9875 		else
9876 		  {
9877 		    use_rela = false;
9878 		    use_rela_initialised = true;
9879 		  }
9880 	      }
9881 	    else
9882 	      {
9883 		/* The section size is not divisible by either -
9884 		   something is wrong.  */
9885 		_bfd_error_handler (_("%pB: unable to sort relocs - "
9886 				      "they are of an unknown size"), abfd);
9887 		bfd_set_error (bfd_error_invalid_operation);
9888 		return 0;
9889 	      }
9890 	  }
9891 
9892       if (! use_rela_initialised)
9893 	/* Make a guess.  */
9894 	use_rela = true;
9895     }
9896   else if (rela_dyn != NULL && rela_dyn->size > 0)
9897     use_rela = true;
9898   else if (rel_dyn != NULL && rel_dyn->size > 0)
9899     use_rela = false;
9900   else
9901     return 0;
9902 
9903   if (use_rela)
9904     {
9905       dynamic_relocs = rela_dyn;
9906       ext_size = bed->s->sizeof_rela;
9907       swap_in = bed->s->swap_reloca_in;
9908       swap_out = bed->s->swap_reloca_out;
9909     }
9910   else
9911     {
9912       dynamic_relocs = rel_dyn;
9913       ext_size = bed->s->sizeof_rel;
9914       swap_in = bed->s->swap_reloc_in;
9915       swap_out = bed->s->swap_reloc_out;
9916     }
9917 
9918   size = 0;
9919   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
9920     if (lo->type == bfd_indirect_link_order)
9921       size += lo->u.indirect.section->size;
9922 
9923   if (size != dynamic_relocs->size)
9924     return 0;
9925 
9926   sort_elt = (sizeof (struct elf_link_sort_rela)
9927 	      + (i2e - 1) * sizeof (Elf_Internal_Rela));
9928 
9929   count = dynamic_relocs->size / ext_size;
9930   if (count == 0)
9931     return 0;
9932   sort = (bfd_byte *) bfd_zmalloc (sort_elt * count);
9933 
9934   if (sort == NULL)
9935     {
9936       (*info->callbacks->warning)
9937 	(info, _("not enough memory to sort relocations"), 0, abfd, 0, 0);
9938       return 0;
9939     }
9940 
9941   if (bed->s->arch_size == 32)
9942     r_sym_mask = ~(bfd_vma) 0xff;
9943   else
9944     r_sym_mask = ~(bfd_vma) 0xffffffff;
9945 
9946   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
9947     if (lo->type == bfd_indirect_link_order)
9948       {
9949 	bfd_byte *erel, *erelend;
9950 	asection *o = lo->u.indirect.section;
9951 
9952 	if (o->contents == NULL && o->size != 0)
9953 	  {
9954 	    /* This is a reloc section that is being handled as a normal
9955 	       section.  See bfd_section_from_shdr.  We can't combine
9956 	       relocs in this case.  */
9957 	    free (sort);
9958 	    return 0;
9959 	  }
9960 	erel = o->contents;
9961 	erelend = o->contents + o->size;
9962 	p = sort + o->output_offset * opb / ext_size * sort_elt;
9963 
9964 	while (erel < erelend)
9965 	  {
9966 	    struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
9967 
9968 	    (*swap_in) (abfd, erel, s->rela);
9969 	    s->type = (*bed->elf_backend_reloc_type_class) (info, o, s->rela);
9970 	    s->u.sym_mask = r_sym_mask;
9971 	    p += sort_elt;
9972 	    erel += ext_size;
9973 	  }
9974       }
9975 
9976   qsort (sort, count, sort_elt, elf_link_sort_cmp1);
9977 
9978   for (i = 0, p = sort; i < count; i++, p += sort_elt)
9979     {
9980       struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
9981       if (s->type != reloc_class_relative)
9982 	break;
9983     }
9984   ret = i;
9985   s_non_relative = p;
9986 
9987   sq = (struct elf_link_sort_rela *) s_non_relative;
9988   for (; i < count; i++, p += sort_elt)
9989     {
9990       struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
9991       if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
9992 	sq = sp;
9993       sp->u.offset = sq->rela->r_offset;
9994     }
9995 
9996   qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
9997 
9998   struct elf_link_hash_table *htab = elf_hash_table (info);
9999   if (htab->srelplt && htab->srelplt->output_section == dynamic_relocs)
10000     {
10001       /* We have plt relocs in .rela.dyn.  */
10002       sq = (struct elf_link_sort_rela *) sort;
10003       for (i = 0; i < count; i++)
10004 	if (sq[count - i - 1].type != reloc_class_plt)
10005 	  break;
10006       if (i != 0 && htab->srelplt->size == i * ext_size)
10007 	{
10008 	  struct bfd_link_order **plo;
10009 	  /* Put srelplt link_order last.  This is so the output_offset
10010 	     set in the next loop is correct for DT_JMPREL.  */
10011 	  for (plo = &dynamic_relocs->map_head.link_order; *plo != NULL; )
10012 	    if ((*plo)->type == bfd_indirect_link_order
10013 		&& (*plo)->u.indirect.section == htab->srelplt)
10014 	      {
10015 		lo = *plo;
10016 		*plo = lo->next;
10017 	      }
10018 	    else
10019 	      plo = &(*plo)->next;
10020 	  *plo = lo;
10021 	  lo->next = NULL;
10022 	  dynamic_relocs->map_tail.link_order = lo;
10023 	}
10024     }
10025 
10026   p = sort;
10027   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
10028     if (lo->type == bfd_indirect_link_order)
10029       {
10030 	bfd_byte *erel, *erelend;
10031 	asection *o = lo->u.indirect.section;
10032 
10033 	erel = o->contents;
10034 	erelend = o->contents + o->size;
10035 	o->output_offset = (p - sort) / sort_elt * ext_size / opb;
10036 	while (erel < erelend)
10037 	  {
10038 	    struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
10039 	    (*swap_out) (abfd, s->rela, erel);
10040 	    p += sort_elt;
10041 	    erel += ext_size;
10042 	  }
10043       }
10044 
10045   free (sort);
10046   *psec = dynamic_relocs;
10047   return ret;
10048 }
10049 
10050 /* Add a symbol to the output symbol string table.  */
10051 
10052 static int
elf_link_output_symstrtab(void * finf,const char * name,Elf_Internal_Sym * elfsym,asection * input_sec,struct elf_link_hash_entry * h)10053 elf_link_output_symstrtab (void *finf,
10054 			   const char *name,
10055 			   Elf_Internal_Sym *elfsym,
10056 			   asection *input_sec,
10057 			   struct elf_link_hash_entry *h)
10058 {
10059   struct elf_final_link_info *flinfo = finf;
10060   int (*output_symbol_hook)
10061     (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
10062      struct elf_link_hash_entry *);
10063   struct elf_link_hash_table *hash_table;
10064   const struct elf_backend_data *bed;
10065   bfd_size_type strtabsize;
10066 
10067   BFD_ASSERT (elf_onesymtab (flinfo->output_bfd));
10068 
10069   bed = get_elf_backend_data (flinfo->output_bfd);
10070   output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
10071   if (output_symbol_hook != NULL)
10072     {
10073       int ret = (*output_symbol_hook) (flinfo->info, name, elfsym, input_sec, h);
10074       if (ret != 1)
10075 	return ret;
10076     }
10077 
10078   if (ELF_ST_TYPE (elfsym->st_info) == STT_GNU_IFUNC)
10079     elf_tdata (flinfo->output_bfd)->has_gnu_osabi |= elf_gnu_osabi_ifunc;
10080   if (ELF_ST_BIND (elfsym->st_info) == STB_GNU_UNIQUE)
10081     elf_tdata (flinfo->output_bfd)->has_gnu_osabi |= elf_gnu_osabi_unique;
10082 
10083   if (name == NULL || *name == '\0')
10084     elfsym->st_name = (unsigned long) -1;
10085   else
10086     {
10087       /* Call _bfd_elf_strtab_offset after _bfd_elf_strtab_finalize
10088 	 to get the final offset for st_name.  */
10089       char *versioned_name = (char *) name;
10090       if (h != NULL)
10091 	{
10092 	  if (h->versioned == versioned && h->def_dynamic)
10093 	    {
10094 	      /* Keep only one '@' for versioned symbols defined in
10095 	         shared objects.  */
10096 	      char *version = strrchr (name, ELF_VER_CHR);
10097 	      char *base_end = strchr (name, ELF_VER_CHR);
10098 	      if (version != base_end)
10099 		{
10100 		  size_t base_len;
10101 		  size_t len = strlen (name);
10102 		  versioned_name = bfd_alloc (flinfo->output_bfd, len);
10103 		  if (versioned_name == NULL)
10104 		    return 0;
10105 		  base_len = base_end - name;
10106 		  memcpy (versioned_name, name, base_len);
10107 		  memcpy (versioned_name + base_len, version,
10108 			  len - base_len);
10109 		}
10110 	    }
10111 	}
10112       else if (flinfo->info->unique_symbol
10113 	       && ELF_ST_BIND (elfsym->st_info) == STB_LOCAL)
10114 	{
10115 	  struct local_hash_entry *lh;
10116 	  size_t count_len;
10117 	  size_t base_len;
10118 	  char buf[30];
10119 	  switch (ELF_ST_TYPE (elfsym->st_info))
10120 	    {
10121 	    case STT_FILE:
10122 	    case STT_SECTION:
10123 	      break;
10124 	    default:
10125 	      lh = (struct local_hash_entry *) bfd_hash_lookup
10126 		     (&flinfo->local_hash_table, name, true, false);
10127 	      if (lh == NULL)
10128 		return 0;
10129 	      /* Always append ".COUNT" to local symbols to avoid
10130 		 potential conflicts with local symbol "XXX.COUNT".  */
10131 	      sprintf (buf, "%lx", lh->count);
10132 	      base_len = lh->size;
10133 	      if (!base_len)
10134 		{
10135 		  base_len = strlen (name);
10136 		  lh->size = base_len;
10137 		}
10138 	      count_len = strlen (buf);
10139 	      versioned_name = bfd_alloc (flinfo->output_bfd,
10140 					  base_len + count_len + 2);
10141 	      if (versioned_name == NULL)
10142 		return 0;
10143 	      memcpy (versioned_name, name, base_len);
10144 	      versioned_name[base_len] = '.';
10145 	      memcpy (versioned_name + base_len + 1, buf,
10146 		      count_len + 1);
10147 	      lh->count++;
10148 	      break;
10149 	    }
10150 	}
10151       elfsym->st_name
10152 	= (unsigned long) _bfd_elf_strtab_add (flinfo->symstrtab,
10153 					       versioned_name, false);
10154       if (elfsym->st_name == (unsigned long) -1)
10155 	return 0;
10156     }
10157 
10158   hash_table = elf_hash_table (flinfo->info);
10159   strtabsize = hash_table->strtabsize;
10160   if (strtabsize <= flinfo->output_bfd->symcount)
10161     {
10162       strtabsize += strtabsize;
10163       hash_table->strtabsize = strtabsize;
10164       strtabsize *= sizeof (*hash_table->strtab);
10165       hash_table->strtab
10166 	= (struct elf_sym_strtab *) bfd_realloc (hash_table->strtab,
10167 						 strtabsize);
10168       if (hash_table->strtab == NULL)
10169 	return 0;
10170     }
10171   hash_table->strtab[flinfo->output_bfd->symcount].sym = *elfsym;
10172   hash_table->strtab[flinfo->output_bfd->symcount].dest_index
10173     = flinfo->output_bfd->symcount;
10174   flinfo->output_bfd->symcount += 1;
10175 
10176   return 1;
10177 }
10178 
10179 /* Swap symbols out to the symbol table and flush the output symbols to
10180    the file.  */
10181 
10182 static bool
elf_link_swap_symbols_out(struct elf_final_link_info * flinfo)10183 elf_link_swap_symbols_out (struct elf_final_link_info *flinfo)
10184 {
10185   struct elf_link_hash_table *hash_table = elf_hash_table (flinfo->info);
10186   size_t amt;
10187   size_t i;
10188   const struct elf_backend_data *bed;
10189   bfd_byte *symbuf;
10190   Elf_Internal_Shdr *hdr;
10191   file_ptr pos;
10192   bool ret;
10193 
10194   if (flinfo->output_bfd->symcount == 0)
10195     return true;
10196 
10197   BFD_ASSERT (elf_onesymtab (flinfo->output_bfd));
10198 
10199   bed = get_elf_backend_data (flinfo->output_bfd);
10200 
10201   amt = bed->s->sizeof_sym * flinfo->output_bfd->symcount;
10202   symbuf = (bfd_byte *) bfd_malloc (amt);
10203   if (symbuf == NULL)
10204     return false;
10205 
10206   if (flinfo->symshndxbuf)
10207     {
10208       amt = sizeof (Elf_External_Sym_Shndx);
10209       amt *= bfd_get_symcount (flinfo->output_bfd);
10210       flinfo->symshndxbuf = (Elf_External_Sym_Shndx *) bfd_zmalloc (amt);
10211       if (flinfo->symshndxbuf == NULL)
10212 	{
10213 	  free (symbuf);
10214 	  return false;
10215 	}
10216     }
10217 
10218   /* Now swap out the symbols.  */
10219   for (i = 0; i < flinfo->output_bfd->symcount; i++)
10220     {
10221       struct elf_sym_strtab *elfsym = &hash_table->strtab[i];
10222       if (elfsym->sym.st_name == (unsigned long) -1)
10223 	elfsym->sym.st_name = 0;
10224       else
10225 	elfsym->sym.st_name
10226 	  = (unsigned long) _bfd_elf_strtab_offset (flinfo->symstrtab,
10227 						    elfsym->sym.st_name);
10228 
10229       /* Inform the linker of the addition of this symbol.  */
10230 
10231       if (flinfo->info->callbacks->ctf_new_symbol)
10232 	flinfo->info->callbacks->ctf_new_symbol (elfsym->dest_index,
10233 						 &elfsym->sym);
10234 
10235       bed->s->swap_symbol_out (flinfo->output_bfd, &elfsym->sym,
10236 			       ((bfd_byte *) symbuf
10237 				+ (elfsym->dest_index
10238 				   * bed->s->sizeof_sym)),
10239 			       NPTR_ADD (flinfo->symshndxbuf,
10240 					 elfsym->dest_index));
10241     }
10242 
10243   hdr = &elf_tdata (flinfo->output_bfd)->symtab_hdr;
10244   pos = hdr->sh_offset + hdr->sh_size;
10245   amt = bed->s->sizeof_sym * flinfo->output_bfd->symcount;
10246   if (bfd_seek (flinfo->output_bfd, pos, SEEK_SET) == 0
10247       && bfd_write (symbuf, amt, flinfo->output_bfd) == amt)
10248     {
10249       hdr->sh_size += amt;
10250       ret = true;
10251     }
10252   else
10253     ret = false;
10254 
10255   free (symbuf);
10256 
10257   free (hash_table->strtab);
10258   hash_table->strtab = NULL;
10259 
10260   return ret;
10261 }
10262 
10263 /* Return TRUE if the dynamic symbol SYM in ABFD is supported.  */
10264 
10265 static bool
check_dynsym(bfd * abfd,Elf_Internal_Sym * sym)10266 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
10267 {
10268   if (sym->st_shndx >= (SHN_LORESERVE & 0xffff)
10269       && sym->st_shndx < SHN_LORESERVE)
10270     {
10271       /* The gABI doesn't support dynamic symbols in output sections
10272 	 beyond 64k.  */
10273       _bfd_error_handler
10274 	/* xgettext:c-format */
10275 	(_("%pB: too many sections: %d (>= %d)"),
10276 	 abfd, bfd_count_sections (abfd), SHN_LORESERVE & 0xffff);
10277       bfd_set_error (bfd_error_nonrepresentable_section);
10278       return false;
10279     }
10280   return true;
10281 }
10282 
10283 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
10284    allowing an unsatisfied unversioned symbol in the DSO to match a
10285    versioned symbol that would normally require an explicit version.
10286    We also handle the case that a DSO references a hidden symbol
10287    which may be satisfied by a versioned symbol in another DSO.  */
10288 
10289 static bool
elf_link_check_versioned_symbol(struct bfd_link_info * info,const struct elf_backend_data * bed,struct elf_link_hash_entry * h)10290 elf_link_check_versioned_symbol (struct bfd_link_info *info,
10291 				 const struct elf_backend_data *bed,
10292 				 struct elf_link_hash_entry *h)
10293 {
10294   bfd *abfd;
10295   struct elf_link_loaded_list *loaded;
10296 
10297   if (!is_elf_hash_table (info->hash))
10298     return false;
10299 
10300   /* Check indirect symbol.  */
10301   while (h->root.type == bfd_link_hash_indirect)
10302     h = (struct elf_link_hash_entry *) h->root.u.i.link;
10303 
10304   switch (h->root.type)
10305     {
10306     default:
10307       abfd = NULL;
10308       break;
10309 
10310     case bfd_link_hash_undefined:
10311     case bfd_link_hash_undefweak:
10312       abfd = h->root.u.undef.abfd;
10313       if (abfd == NULL
10314 	  || (abfd->flags & DYNAMIC) == 0
10315 	  || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
10316 	return false;
10317       break;
10318 
10319     case bfd_link_hash_defined:
10320     case bfd_link_hash_defweak:
10321       abfd = h->root.u.def.section->owner;
10322       break;
10323 
10324     case bfd_link_hash_common:
10325       abfd = h->root.u.c.p->section->owner;
10326       break;
10327     }
10328   BFD_ASSERT (abfd != NULL);
10329 
10330   for (loaded = elf_hash_table (info)->dyn_loaded;
10331        loaded != NULL;
10332        loaded = loaded->next)
10333     {
10334       bfd *input;
10335       Elf_Internal_Shdr *hdr;
10336       size_t symcount;
10337       size_t extsymcount;
10338       size_t extsymoff;
10339       Elf_Internal_Shdr *versymhdr;
10340       Elf_Internal_Sym *isym;
10341       Elf_Internal_Sym *isymend;
10342       Elf_Internal_Sym *isymbuf;
10343       Elf_External_Versym *ever;
10344       Elf_External_Versym *extversym;
10345 
10346       input = loaded->abfd;
10347 
10348       /* We check each DSO for a possible hidden versioned definition.  */
10349       if (input == abfd
10350 	  || elf_dynversym (input) == 0)
10351 	continue;
10352 
10353       hdr = &elf_tdata (input)->dynsymtab_hdr;
10354 
10355       symcount = hdr->sh_size / bed->s->sizeof_sym;
10356       if (elf_bad_symtab (input))
10357 	{
10358 	  extsymcount = symcount;
10359 	  extsymoff = 0;
10360 	}
10361       else
10362 	{
10363 	  extsymcount = symcount - hdr->sh_info;
10364 	  extsymoff = hdr->sh_info;
10365 	}
10366 
10367       if (extsymcount == 0)
10368 	continue;
10369 
10370       isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
10371 				      NULL, NULL, NULL);
10372       if (isymbuf == NULL)
10373 	return false;
10374 
10375       /* Read in any version definitions.  */
10376       versymhdr = &elf_tdata (input)->dynversym_hdr;
10377       if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
10378 	  || (extversym = (Elf_External_Versym *)
10379 	      _bfd_malloc_and_read (input, versymhdr->sh_size,
10380 				    versymhdr->sh_size)) == NULL)
10381 	{
10382 	  free (isymbuf);
10383 	  return false;
10384 	}
10385 
10386       ever = extversym + extsymoff;
10387       isymend = isymbuf + extsymcount;
10388       for (isym = isymbuf; isym < isymend; isym++, ever++)
10389 	{
10390 	  const char *name;
10391 	  Elf_Internal_Versym iver;
10392 	  unsigned short version_index;
10393 
10394 	  if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
10395 	      || isym->st_shndx == SHN_UNDEF)
10396 	    continue;
10397 
10398 	  name = bfd_elf_string_from_elf_section (input,
10399 						  hdr->sh_link,
10400 						  isym->st_name);
10401 	  if (strcmp (name, h->root.root.string) != 0)
10402 	    continue;
10403 
10404 	  _bfd_elf_swap_versym_in (input, ever, &iver);
10405 
10406 	  if ((iver.vs_vers & VERSYM_HIDDEN) == 0
10407 	      && !(h->def_regular
10408 		   && h->forced_local))
10409 	    {
10410 	      /* If we have a non-hidden versioned sym, then it should
10411 		 have provided a definition for the undefined sym unless
10412 		 it is defined in a non-shared object and forced local.
10413 	       */
10414 	      abort ();
10415 	    }
10416 
10417 	  version_index = iver.vs_vers & VERSYM_VERSION;
10418 	  if (version_index == 1 || version_index == 2)
10419 	    {
10420 	      /* This is the base or first version.  We can use it.  */
10421 	      free (extversym);
10422 	      free (isymbuf);
10423 	      return true;
10424 	    }
10425 	}
10426 
10427       free (extversym);
10428       free (isymbuf);
10429     }
10430 
10431   return false;
10432 }
10433 
10434 /* Convert ELF common symbol TYPE.  */
10435 
10436 static int
elf_link_convert_common_type(struct bfd_link_info * info,int type)10437 elf_link_convert_common_type (struct bfd_link_info *info, int type)
10438 {
10439   /* Commom symbol can only appear in relocatable link.  */
10440   if (!bfd_link_relocatable (info))
10441     abort ();
10442   switch (info->elf_stt_common)
10443     {
10444     case unchanged:
10445       break;
10446     case elf_stt_common:
10447       type = STT_COMMON;
10448       break;
10449     case no_elf_stt_common:
10450       type = STT_OBJECT;
10451       break;
10452     }
10453   return type;
10454 }
10455 
10456 /* Add an external symbol to the symbol table.  This is called from
10457    the hash table traversal routine.  When generating a shared object,
10458    we go through the symbol table twice.  The first time we output
10459    anything that might have been forced to local scope in a version
10460    script.  The second time we output the symbols that are still
10461    global symbols.  */
10462 
10463 static bool
elf_link_output_extsym(struct bfd_hash_entry * bh,void * data)10464 elf_link_output_extsym (struct bfd_hash_entry *bh, void *data)
10465 {
10466   struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) bh;
10467   struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
10468   struct elf_final_link_info *flinfo = eoinfo->flinfo;
10469   bool strip;
10470   Elf_Internal_Sym sym;
10471   asection *input_sec;
10472   const struct elf_backend_data *bed;
10473   long indx;
10474   int ret;
10475   unsigned int type;
10476 
10477   if (h->root.type == bfd_link_hash_warning)
10478     {
10479       h = (struct elf_link_hash_entry *) h->root.u.i.link;
10480       if (h->root.type == bfd_link_hash_new)
10481 	return true;
10482     }
10483 
10484   /* Decide whether to output this symbol in this pass.  */
10485   if (eoinfo->localsyms)
10486     {
10487       if (!h->forced_local)
10488 	return true;
10489     }
10490   else
10491     {
10492       if (h->forced_local)
10493 	return true;
10494     }
10495 
10496   bed = get_elf_backend_data (flinfo->output_bfd);
10497 
10498   if (h->root.type == bfd_link_hash_undefined)
10499     {
10500       /* If we have an undefined symbol reference here then it must have
10501 	 come from a shared library that is being linked in.  (Undefined
10502 	 references in regular files have already been handled unless
10503 	 they are in unreferenced sections which are removed by garbage
10504 	 collection).  */
10505       bool ignore_undef = false;
10506 
10507       /* Some symbols may be special in that the fact that they're
10508 	 undefined can be safely ignored - let backend determine that.  */
10509       if (bed->elf_backend_ignore_undef_symbol)
10510 	ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
10511 
10512       /* If we are reporting errors for this situation then do so now.  */
10513       if (!ignore_undef
10514 	  && h->ref_dynamic_nonweak
10515 	  && (!h->ref_regular || flinfo->info->gc_sections)
10516 	  && !elf_link_check_versioned_symbol (flinfo->info, bed, h)
10517 	  && flinfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
10518 	{
10519 	  flinfo->info->callbacks->undefined_symbol
10520 	    (flinfo->info, h->root.root.string,
10521 	     h->ref_regular ? NULL : h->root.u.undef.abfd, NULL, 0,
10522 	     flinfo->info->unresolved_syms_in_shared_libs == RM_DIAGNOSE
10523 	     && !flinfo->info->warn_unresolved_syms);
10524 	}
10525 
10526       /* Strip a global symbol defined in a discarded section.  */
10527       if (h->indx == -3)
10528 	return true;
10529     }
10530 
10531   /* We should also warn if a forced local symbol is referenced from
10532      shared libraries.  */
10533   if (bfd_link_executable (flinfo->info)
10534       && h->forced_local
10535       && h->ref_dynamic
10536       && h->def_regular
10537       && !h->dynamic_def
10538       && h->ref_dynamic_nonweak
10539       && !elf_link_check_versioned_symbol (flinfo->info, bed, h))
10540     {
10541       bfd *def_bfd;
10542       const char *msg;
10543       struct elf_link_hash_entry *hi = h;
10544 
10545       /* Check indirect symbol.  */
10546       while (hi->root.type == bfd_link_hash_indirect)
10547 	hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
10548 
10549       if (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL)
10550 	/* xgettext:c-format */
10551 	msg = _("%pB: internal symbol `%s' in %pB is referenced by DSO");
10552       else if (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
10553 	/* xgettext:c-format */
10554 	msg = _("%pB: hidden symbol `%s' in %pB is referenced by DSO");
10555       else
10556 	/* xgettext:c-format */
10557 	msg = _("%pB: local symbol `%s' in %pB is referenced by DSO");
10558       def_bfd = flinfo->output_bfd;
10559       if (hi->root.u.def.section != bfd_abs_section_ptr)
10560 	def_bfd = hi->root.u.def.section->owner;
10561       _bfd_error_handler (msg, flinfo->output_bfd,
10562 			  h->root.root.string, def_bfd);
10563       bfd_set_error (bfd_error_bad_value);
10564       eoinfo->failed = true;
10565       return false;
10566     }
10567 
10568   /* We don't want to output symbols that have never been mentioned by
10569      a regular file, or that we have been told to strip.  However, if
10570      h->indx is set to -2, the symbol is used by a reloc and we must
10571      output it.  */
10572   strip = false;
10573   if (h->indx == -2)
10574     ;
10575   else if ((h->def_dynamic
10576 	    || h->ref_dynamic
10577 	    || h->root.type == bfd_link_hash_new)
10578 	   && !h->def_regular
10579 	   && !h->ref_regular)
10580     strip = true;
10581   else if (flinfo->info->strip == strip_all)
10582     strip = true;
10583   else if (flinfo->info->strip == strip_some
10584 	   && bfd_hash_lookup (flinfo->info->keep_hash,
10585 			       h->root.root.string, false, false) == NULL)
10586     strip = true;
10587   else if ((h->root.type == bfd_link_hash_defined
10588 	    || h->root.type == bfd_link_hash_defweak)
10589 	   && ((flinfo->info->strip_discarded
10590 		&& discarded_section (h->root.u.def.section))
10591 	       || ((h->root.u.def.section->flags & SEC_LINKER_CREATED) == 0
10592 		   && h->root.u.def.section->owner != NULL
10593 		   && (h->root.u.def.section->owner->flags & BFD_PLUGIN) != 0)))
10594     strip = true;
10595   else if ((h->root.type == bfd_link_hash_undefined
10596 	    || h->root.type == bfd_link_hash_undefweak)
10597 	   && h->root.u.undef.abfd != NULL
10598 	   && (h->root.u.undef.abfd->flags & BFD_PLUGIN) != 0)
10599     strip = true;
10600 
10601   type = h->type;
10602 
10603   /* If we're stripping it, and it's not a dynamic symbol, there's
10604      nothing else to do.   However, if it is a forced local symbol or
10605      an ifunc symbol we need to give the backend finish_dynamic_symbol
10606      function a chance to make it dynamic.  */
10607   if (strip
10608       && h->dynindx == -1
10609       && type != STT_GNU_IFUNC
10610       && !h->forced_local)
10611     return true;
10612 
10613   sym.st_value = 0;
10614   sym.st_size = h->size;
10615   sym.st_other = h->other;
10616   switch (h->root.type)
10617     {
10618     default:
10619     case bfd_link_hash_new:
10620     case bfd_link_hash_warning:
10621       abort ();
10622       return false;
10623 
10624     case bfd_link_hash_undefined:
10625     case bfd_link_hash_undefweak:
10626       input_sec = bfd_und_section_ptr;
10627       sym.st_shndx = SHN_UNDEF;
10628       break;
10629 
10630     case bfd_link_hash_defined:
10631     case bfd_link_hash_defweak:
10632       {
10633 	input_sec = h->root.u.def.section;
10634 	if (input_sec->output_section != NULL)
10635 	  {
10636 	    sym.st_shndx =
10637 	      _bfd_elf_section_from_bfd_section (flinfo->output_bfd,
10638 						 input_sec->output_section);
10639 	    if (sym.st_shndx == SHN_BAD)
10640 	      {
10641 		_bfd_error_handler
10642 		  /* xgettext:c-format */
10643 		  (_("%pB: could not find output section %pA for input section %pA"),
10644 		   flinfo->output_bfd, input_sec->output_section, input_sec);
10645 		bfd_set_error (bfd_error_nonrepresentable_section);
10646 		eoinfo->failed = true;
10647 		return false;
10648 	      }
10649 
10650 	    /* ELF symbols in relocatable files are section relative,
10651 	       but in nonrelocatable files they are virtual
10652 	       addresses.  */
10653 	    sym.st_value = h->root.u.def.value + input_sec->output_offset;
10654 	    if (!bfd_link_relocatable (flinfo->info))
10655 	      {
10656 		sym.st_value += input_sec->output_section->vma;
10657 		if (h->type == STT_TLS)
10658 		  {
10659 		    asection *tls_sec = elf_hash_table (flinfo->info)->tls_sec;
10660 		    if (tls_sec != NULL)
10661 		      sym.st_value -= tls_sec->vma;
10662 		  }
10663 	      }
10664 	  }
10665 	else
10666 	  {
10667 	    BFD_ASSERT (input_sec->owner == NULL
10668 			|| (input_sec->owner->flags & DYNAMIC) != 0);
10669 	    sym.st_shndx = SHN_UNDEF;
10670 	    input_sec = bfd_und_section_ptr;
10671 	  }
10672       }
10673       break;
10674 
10675     case bfd_link_hash_common:
10676       input_sec = h->root.u.c.p->section;
10677       sym.st_shndx = bed->common_section_index (input_sec);
10678       sym.st_value = 1 << h->root.u.c.p->alignment_power;
10679       break;
10680 
10681     case bfd_link_hash_indirect:
10682       /* These symbols are created by symbol versioning.  They point
10683 	 to the decorated version of the name.  For example, if the
10684 	 symbol foo@@GNU_1.2 is the default, which should be used when
10685 	 foo is used with no version, then we add an indirect symbol
10686 	 foo which points to foo@@GNU_1.2.  We ignore these symbols,
10687 	 since the indirected symbol is already in the hash table.  */
10688       return true;
10689     }
10690 
10691   if (type == STT_COMMON || type == STT_OBJECT)
10692     switch (h->root.type)
10693       {
10694       case bfd_link_hash_common:
10695 	type = elf_link_convert_common_type (flinfo->info, type);
10696 	break;
10697       case bfd_link_hash_defined:
10698       case bfd_link_hash_defweak:
10699 	if (bed->common_definition (&sym))
10700 	  type = elf_link_convert_common_type (flinfo->info, type);
10701 	else
10702 	  type = STT_OBJECT;
10703 	break;
10704       case bfd_link_hash_undefined:
10705       case bfd_link_hash_undefweak:
10706 	break;
10707       default:
10708 	abort ();
10709       }
10710 
10711   if (h->forced_local)
10712     {
10713       sym.st_info = ELF_ST_INFO (STB_LOCAL, type);
10714       /* Turn off visibility on local symbol.  */
10715       sym.st_other &= ~ELF_ST_VISIBILITY (-1);
10716     }
10717   /* Set STB_GNU_UNIQUE only if symbol is defined in regular object.  */
10718   else if (h->unique_global && h->def_regular)
10719     sym.st_info = ELF_ST_INFO (STB_GNU_UNIQUE, type);
10720   else if (h->root.type == bfd_link_hash_undefweak
10721 	   || h->root.type == bfd_link_hash_defweak)
10722     sym.st_info = ELF_ST_INFO (STB_WEAK, type);
10723   else
10724     sym.st_info = ELF_ST_INFO (STB_GLOBAL, type);
10725   sym.st_target_internal = h->target_internal;
10726 
10727   /* Give the processor backend a chance to tweak the symbol value,
10728      and also to finish up anything that needs to be done for this
10729      symbol.  FIXME: Not calling elf_backend_finish_dynamic_symbol for
10730      forced local syms when non-shared is due to a historical quirk.
10731      STT_GNU_IFUNC symbol must go through PLT.  */
10732   if ((h->type == STT_GNU_IFUNC
10733        && h->def_regular
10734        && !bfd_link_relocatable (flinfo->info))
10735       || ((h->dynindx != -1
10736 	   || h->forced_local)
10737 	  && ((bfd_link_pic (flinfo->info)
10738 	       && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
10739 		   || h->root.type != bfd_link_hash_undefweak))
10740 	      || !h->forced_local)
10741 	  && elf_hash_table (flinfo->info)->dynamic_sections_created))
10742     {
10743       if (! ((*bed->elf_backend_finish_dynamic_symbol)
10744 	     (flinfo->output_bfd, flinfo->info, h, &sym)))
10745 	{
10746 	  eoinfo->failed = true;
10747 	  return false;
10748 	}
10749     }
10750 
10751   /* If we are marking the symbol as undefined, and there are no
10752      non-weak references to this symbol from a regular object, then
10753      mark the symbol as weak undefined; if there are non-weak
10754      references, mark the symbol as strong.  We can't do this earlier,
10755      because it might not be marked as undefined until the
10756      finish_dynamic_symbol routine gets through with it.  */
10757   if (sym.st_shndx == SHN_UNDEF
10758       && h->ref_regular
10759       && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
10760 	  || ELF_ST_BIND (sym.st_info) == STB_WEAK))
10761     {
10762       int bindtype;
10763       type = ELF_ST_TYPE (sym.st_info);
10764 
10765       /* Turn an undefined IFUNC symbol into a normal FUNC symbol. */
10766       if (type == STT_GNU_IFUNC)
10767 	type = STT_FUNC;
10768 
10769       if (h->ref_regular_nonweak)
10770 	bindtype = STB_GLOBAL;
10771       else
10772 	bindtype = STB_WEAK;
10773       sym.st_info = ELF_ST_INFO (bindtype, type);
10774     }
10775 
10776   /* If this is a symbol defined in a dynamic library, don't use the
10777      symbol size from the dynamic library.  Relinking an executable
10778      against a new library may introduce gratuitous changes in the
10779      executable's symbols if we keep the size.  */
10780   if (sym.st_shndx == SHN_UNDEF
10781       && !h->def_regular
10782       && h->def_dynamic)
10783     sym.st_size = 0;
10784 
10785   /* If a non-weak symbol with non-default visibility is not defined
10786      locally, it is a fatal error.  */
10787   if (!bfd_link_relocatable (flinfo->info)
10788       && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
10789       && ELF_ST_BIND (sym.st_info) != STB_WEAK
10790       && h->root.type == bfd_link_hash_undefined
10791       && !h->def_regular)
10792     {
10793       const char *msg;
10794 
10795       if (ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED)
10796 	/* xgettext:c-format */
10797 	msg = _("%pB: protected symbol `%s' isn't defined");
10798       else if (ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL)
10799 	/* xgettext:c-format */
10800 	msg = _("%pB: internal symbol `%s' isn't defined");
10801       else
10802 	/* xgettext:c-format */
10803 	msg = _("%pB: hidden symbol `%s' isn't defined");
10804       _bfd_error_handler (msg, flinfo->output_bfd, h->root.root.string);
10805       bfd_set_error (bfd_error_bad_value);
10806       eoinfo->failed = true;
10807       return false;
10808     }
10809 
10810   /* If this symbol should be put in the .dynsym section, then put it
10811      there now.  We already know the symbol index.  We also fill in
10812      the entry in the .hash section.  */
10813   if (h->dynindx != -1
10814       && elf_hash_table (flinfo->info)->dynamic_sections_created
10815       && elf_hash_table (flinfo->info)->dynsym != NULL
10816       && !discarded_section (elf_hash_table (flinfo->info)->dynsym))
10817     {
10818       bfd_byte *esym;
10819 
10820       /* Since there is no version information in the dynamic string,
10821 	 if there is no version info in symbol version section, we will
10822 	 have a run-time problem if not linking executable, referenced
10823 	 by shared library, or not bound locally.  */
10824       if (h->verinfo.verdef == NULL
10825 	  && (!bfd_link_executable (flinfo->info)
10826 	      || h->ref_dynamic
10827 	      || !h->def_regular))
10828 	{
10829 	  char *p = strrchr (h->root.root.string, ELF_VER_CHR);
10830 
10831 	  if (p && p [1] != '\0')
10832 	    {
10833 	      _bfd_error_handler
10834 		/* xgettext:c-format */
10835 		(_("%pB: no symbol version section for versioned symbol `%s'"),
10836 		 flinfo->output_bfd, h->root.root.string);
10837 	      eoinfo->failed = true;
10838 	      return false;
10839 	    }
10840 	}
10841 
10842       sym.st_name = h->dynstr_index;
10843       esym = (elf_hash_table (flinfo->info)->dynsym->contents
10844 	      + h->dynindx * bed->s->sizeof_sym);
10845       if (!check_dynsym (flinfo->output_bfd, &sym))
10846 	{
10847 	  eoinfo->failed = true;
10848 	  return false;
10849 	}
10850 
10851       /* Inform the linker of the addition of this symbol.  */
10852 
10853       if (flinfo->info->callbacks->ctf_new_dynsym)
10854 	flinfo->info->callbacks->ctf_new_dynsym (h->dynindx, &sym);
10855 
10856       bed->s->swap_symbol_out (flinfo->output_bfd, &sym, esym, 0);
10857 
10858       if (flinfo->hash_sec != NULL)
10859 	{
10860 	  size_t hash_entry_size;
10861 	  bfd_byte *bucketpos;
10862 	  bfd_vma chain;
10863 	  size_t bucketcount;
10864 	  size_t bucket;
10865 
10866 	  bucketcount = elf_hash_table (flinfo->info)->bucketcount;
10867 	  bucket = h->u.elf_hash_value % bucketcount;
10868 
10869 	  hash_entry_size
10870 	    = elf_section_data (flinfo->hash_sec)->this_hdr.sh_entsize;
10871 	  bucketpos = ((bfd_byte *) flinfo->hash_sec->contents
10872 		       + (bucket + 2) * hash_entry_size);
10873 	  chain = bfd_get (8 * hash_entry_size, flinfo->output_bfd, bucketpos);
10874 	  bfd_put (8 * hash_entry_size, flinfo->output_bfd, h->dynindx,
10875 		   bucketpos);
10876 	  bfd_put (8 * hash_entry_size, flinfo->output_bfd, chain,
10877 		   ((bfd_byte *) flinfo->hash_sec->contents
10878 		    + (bucketcount + 2 + h->dynindx) * hash_entry_size));
10879 	}
10880 
10881       if (flinfo->symver_sec != NULL && flinfo->symver_sec->contents != NULL)
10882 	{
10883 	  Elf_Internal_Versym iversym;
10884 	  Elf_External_Versym *eversym;
10885 
10886 	  if (!h->def_regular && !ELF_COMMON_DEF_P (h))
10887 	    {
10888 	      if (h->verinfo.verdef == NULL
10889 		  || (elf_dyn_lib_class (h->verinfo.verdef->vd_bfd)
10890 		      & (DYN_AS_NEEDED | DYN_DT_NEEDED | DYN_NO_NEEDED)))
10891 		iversym.vs_vers = 1;
10892 	      else
10893 		iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
10894 	    }
10895 	  else
10896 	    {
10897 	      if (h->verinfo.vertree == NULL)
10898 		iversym.vs_vers = 1;
10899 	      else
10900 		iversym.vs_vers = h->verinfo.vertree->vernum + 1;
10901 	      if (flinfo->info->create_default_symver)
10902 		iversym.vs_vers++;
10903 	    }
10904 
10905 	  /* Turn on VERSYM_HIDDEN only if the hidden versioned symbol is
10906 	     defined locally.  */
10907 	  if (h->versioned == versioned_hidden && h->def_regular)
10908 	    iversym.vs_vers |= VERSYM_HIDDEN;
10909 
10910 	  eversym = (Elf_External_Versym *) flinfo->symver_sec->contents;
10911 	  eversym += h->dynindx;
10912 	  _bfd_elf_swap_versym_out (flinfo->output_bfd, &iversym, eversym);
10913 	}
10914     }
10915 
10916   /* If the symbol is undefined, and we didn't output it to .dynsym,
10917      strip it from .symtab too.  Obviously we can't do this for
10918      relocatable output or when needed for --emit-relocs.  */
10919   else if (input_sec == bfd_und_section_ptr
10920 	   && h->indx != -2
10921 	   /* PR 22319 Do not strip global undefined symbols marked as being needed.  */
10922 	   && (h->mark != 1 || ELF_ST_BIND (sym.st_info) != STB_GLOBAL)
10923 	   && !bfd_link_relocatable (flinfo->info))
10924     return true;
10925 
10926   /* Also strip others that we couldn't earlier due to dynamic symbol
10927      processing.  */
10928   if (strip)
10929     return true;
10930   if ((input_sec->flags & SEC_EXCLUDE) != 0)
10931     return true;
10932 
10933   /* Output a FILE symbol so that following locals are not associated
10934      with the wrong input file.  We need one for forced local symbols
10935      if we've seen more than one FILE symbol or when we have exactly
10936      one FILE symbol but global symbols are present in a file other
10937      than the one with the FILE symbol.  We also need one if linker
10938      defined symbols are present.  In practice these conditions are
10939      always met, so just emit the FILE symbol unconditionally.  */
10940   if (eoinfo->localsyms
10941       && !eoinfo->file_sym_done
10942       && eoinfo->flinfo->filesym_count != 0)
10943     {
10944       Elf_Internal_Sym fsym;
10945 
10946       memset (&fsym, 0, sizeof (fsym));
10947       fsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
10948       fsym.st_shndx = SHN_ABS;
10949       if (!elf_link_output_symstrtab (eoinfo->flinfo, NULL, &fsym,
10950 				      bfd_und_section_ptr, NULL))
10951 	return false;
10952 
10953       eoinfo->file_sym_done = true;
10954     }
10955 
10956   indx = bfd_get_symcount (flinfo->output_bfd);
10957   ret = elf_link_output_symstrtab (flinfo, h->root.root.string, &sym,
10958 				   input_sec, h);
10959   if (ret == 0)
10960     {
10961       eoinfo->failed = true;
10962       return false;
10963     }
10964   else if (ret == 1)
10965     h->indx = indx;
10966   else if (h->indx == -2)
10967     abort();
10968 
10969   return true;
10970 }
10971 
10972 /* Return TRUE if special handling is done for relocs in SEC against
10973    symbols defined in discarded sections.  */
10974 
10975 static bool
elf_section_ignore_discarded_relocs(asection * sec)10976 elf_section_ignore_discarded_relocs (asection *sec)
10977 {
10978   const struct elf_backend_data *bed;
10979 
10980   switch (sec->sec_info_type)
10981     {
10982     case SEC_INFO_TYPE_STABS:
10983     case SEC_INFO_TYPE_EH_FRAME:
10984     case SEC_INFO_TYPE_EH_FRAME_ENTRY:
10985     case SEC_INFO_TYPE_SFRAME:
10986       return true;
10987     default:
10988       break;
10989     }
10990 
10991   bed = get_elf_backend_data (sec->owner);
10992   if (bed->elf_backend_ignore_discarded_relocs != NULL
10993       && (*bed->elf_backend_ignore_discarded_relocs) (sec))
10994     return true;
10995 
10996   return false;
10997 }
10998 
10999 /* Return a mask saying how ld should treat relocations in SEC against
11000    symbols defined in discarded sections.  If this function returns
11001    COMPLAIN set, ld will issue a warning message.  If this function
11002    returns PRETEND set, and the discarded section was link-once and the
11003    same size as the kept link-once section, ld will pretend that the
11004    symbol was actually defined in the kept section.  Otherwise ld will
11005    zero the reloc (at least that is the intent, but some cooperation by
11006    the target dependent code is needed, particularly for REL targets).  */
11007 
11008 unsigned int
_bfd_elf_default_action_discarded(asection * sec)11009 _bfd_elf_default_action_discarded (asection *sec)
11010 {
11011   const struct elf_backend_data *bed;
11012   bed = get_elf_backend_data (sec->owner);
11013 
11014   if (sec->flags & SEC_DEBUGGING)
11015     return PRETEND;
11016 
11017   if (strcmp (".eh_frame", sec->name) == 0)
11018     return 0;
11019 
11020   if (bed->elf_backend_can_make_multiple_eh_frame
11021       && strncmp (sec->name, ".eh_frame.", 10) == 0)
11022     return 0;
11023 
11024   if (strcmp (".sframe", sec->name) == 0)
11025     return 0;
11026 
11027   if (strcmp (".gcc_except_table", sec->name) == 0)
11028     return 0;
11029 
11030   return COMPLAIN | PRETEND;
11031 }
11032 
11033 /* Find a match between a section and a member of a section group.  */
11034 
11035 static asection *
match_group_member(asection * sec,asection * group,struct bfd_link_info * info)11036 match_group_member (asection *sec, asection *group,
11037 		    struct bfd_link_info *info)
11038 {
11039   asection *first = elf_next_in_group (group);
11040   asection *s = first;
11041 
11042   while (s != NULL)
11043     {
11044       if (bfd_elf_match_symbols_in_sections (s, sec, info))
11045 	return s;
11046 
11047       s = elf_next_in_group (s);
11048       if (s == first)
11049 	break;
11050     }
11051 
11052   return NULL;
11053 }
11054 
11055 /* Check if the kept section of a discarded section SEC can be used
11056    to replace it.  Return the replacement if it is OK.  Otherwise return
11057    NULL.  */
11058 
11059 asection *
_bfd_elf_check_kept_section(asection * sec,struct bfd_link_info * info)11060 _bfd_elf_check_kept_section (asection *sec, struct bfd_link_info *info)
11061 {
11062   asection *kept;
11063 
11064   kept = sec->kept_section;
11065   if (kept != NULL)
11066     {
11067       if ((kept->flags & SEC_GROUP) != 0)
11068 	kept = match_group_member (sec, kept, info);
11069       if (kept != NULL)
11070 	{
11071 	  if ((sec->rawsize != 0 ? sec->rawsize : sec->size)
11072 	      != (kept->rawsize != 0 ? kept->rawsize : kept->size))
11073 	    kept = NULL;
11074 	  else
11075 	    {
11076 	      /* Get the real kept section.  */
11077 	      asection *next;
11078 	      for (next = kept->kept_section;
11079 		   next != NULL;
11080 		   next = next->kept_section)
11081 		kept = next;
11082 	    }
11083 	}
11084       sec->kept_section = kept;
11085     }
11086   return kept;
11087 }
11088 
11089 /* Link an input file into the linker output file.  This function
11090    handles all the sections and relocations of the input file at once.
11091    This is so that we only have to read the local symbols once, and
11092    don't have to keep them in memory.  */
11093 
11094 static bool
elf_link_input_bfd(struct elf_final_link_info * flinfo,bfd * input_bfd)11095 elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd)
11096 {
11097   int (*relocate_section)
11098     (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
11099      Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
11100   bfd *output_bfd;
11101   Elf_Internal_Shdr *symtab_hdr;
11102   size_t locsymcount;
11103   size_t extsymoff;
11104   Elf_Internal_Sym *isymbuf;
11105   Elf_Internal_Sym *isym;
11106   Elf_Internal_Sym *isymend;
11107   long *pindex;
11108   asection **ppsection;
11109   asection *o;
11110   const struct elf_backend_data *bed;
11111   struct elf_link_hash_entry **sym_hashes;
11112   bfd_size_type address_size;
11113   bfd_vma r_type_mask;
11114   int r_sym_shift;
11115   bool have_file_sym = false;
11116 
11117   output_bfd = flinfo->output_bfd;
11118   bed = get_elf_backend_data (output_bfd);
11119   relocate_section = bed->elf_backend_relocate_section;
11120 
11121   /* If this is a dynamic object, we don't want to do anything here:
11122      we don't want the local symbols, and we don't want the section
11123      contents.  */
11124   if ((input_bfd->flags & DYNAMIC) != 0)
11125     return true;
11126 
11127   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
11128   if (elf_bad_symtab (input_bfd))
11129     {
11130       locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
11131       extsymoff = 0;
11132     }
11133   else
11134     {
11135       locsymcount = symtab_hdr->sh_info;
11136       extsymoff = symtab_hdr->sh_info;
11137     }
11138 
11139   /* Enable GNU OSABI features in the output BFD that are used in the input
11140      BFD.  */
11141   if (bed->elf_osabi == ELFOSABI_NONE
11142       || bed->elf_osabi == ELFOSABI_GNU
11143       || bed->elf_osabi == ELFOSABI_FREEBSD)
11144     elf_tdata (output_bfd)->has_gnu_osabi
11145       |= (elf_tdata (input_bfd)->has_gnu_osabi
11146 	  & (bfd_link_relocatable (flinfo->info)
11147 	     ? -1 : ~elf_gnu_osabi_retain));
11148 
11149   /* Read the local symbols.  */
11150   isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
11151   if (isymbuf == NULL && locsymcount != 0)
11152     {
11153       isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
11154 				      flinfo->internal_syms,
11155 				      flinfo->external_syms,
11156 				      flinfo->locsym_shndx);
11157       if (isymbuf == NULL)
11158 	return false;
11159     }
11160 
11161   /* Find local symbol sections and adjust values of symbols in
11162      SEC_MERGE sections.  Write out those local symbols we know are
11163      going into the output file.  */
11164   isymend = PTR_ADD (isymbuf, locsymcount);
11165   for (isym = isymbuf, pindex = flinfo->indices, ppsection = flinfo->sections;
11166        isym < isymend;
11167        isym++, pindex++, ppsection++)
11168     {
11169       asection *isec;
11170       const char *name;
11171       Elf_Internal_Sym osym;
11172       long indx;
11173       int ret;
11174 
11175       *pindex = -1;
11176 
11177       if (elf_bad_symtab (input_bfd))
11178 	{
11179 	  if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
11180 	    {
11181 	      *ppsection = NULL;
11182 	      continue;
11183 	    }
11184 	}
11185 
11186       if (isym->st_shndx == SHN_UNDEF)
11187 	isec = bfd_und_section_ptr;
11188       else if (isym->st_shndx == SHN_ABS)
11189 	isec = bfd_abs_section_ptr;
11190       else if (isym->st_shndx == SHN_COMMON)
11191 	isec = bfd_com_section_ptr;
11192       else
11193 	{
11194 	  isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
11195 	  if (isec == NULL)
11196 	    {
11197 	      /* Don't attempt to output symbols with st_shnx in the
11198 		 reserved range other than SHN_ABS and SHN_COMMON.  */
11199 	      isec = bfd_und_section_ptr;
11200 	    }
11201 	  else if (isec->sec_info_type == SEC_INFO_TYPE_MERGE
11202 		   && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
11203 	    isym->st_value =
11204 	      _bfd_merged_section_offset (output_bfd, &isec,
11205 					  elf_section_data (isec)->sec_info,
11206 					  isym->st_value);
11207 	}
11208 
11209       *ppsection = isec;
11210 
11211       /* Don't output the first, undefined, symbol.  In fact, don't
11212 	 output any undefined local symbol.  */
11213       if (isec == bfd_und_section_ptr)
11214 	continue;
11215 
11216       if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
11217 	{
11218 	  /* We never output section symbols.  Instead, we use the
11219 	     section symbol of the corresponding section in the output
11220 	     file.  */
11221 	  continue;
11222 	}
11223 
11224       /* If we are stripping all symbols, we don't want to output this
11225 	 one.  */
11226       if (flinfo->info->strip == strip_all)
11227 	continue;
11228 
11229       /* If we are discarding all local symbols, we don't want to
11230 	 output this one.  If we are generating a relocatable output
11231 	 file, then some of the local symbols may be required by
11232 	 relocs; we output them below as we discover that they are
11233 	 needed.  */
11234       if (flinfo->info->discard == discard_all)
11235 	continue;
11236 
11237       /* If this symbol is defined in a section which we are
11238 	 discarding, we don't need to keep it.  */
11239       if (isym->st_shndx < SHN_LORESERVE
11240 	  && (isec->output_section == NULL
11241 	      || bfd_section_removed_from_list (output_bfd,
11242 						isec->output_section)))
11243 	continue;
11244 
11245       /* Get the name of the symbol.  */
11246       name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
11247 					      isym->st_name);
11248       if (name == NULL)
11249 	return false;
11250 
11251       /* See if we are discarding symbols with this name.  */
11252       if ((flinfo->info->strip == strip_some
11253 	   && (bfd_hash_lookup (flinfo->info->keep_hash, name, false, false)
11254 	       == NULL))
11255 	  || (((flinfo->info->discard == discard_sec_merge
11256 		&& (isec->flags & SEC_MERGE)
11257 		&& !bfd_link_relocatable (flinfo->info))
11258 	       || flinfo->info->discard == discard_l)
11259 	      && bfd_is_local_label_name (input_bfd, name)))
11260 	continue;
11261 
11262       if (ELF_ST_TYPE (isym->st_info) == STT_FILE)
11263 	{
11264 	  if (input_bfd->lto_output)
11265 	    /* -flto puts a temp file name here.  This means builds
11266 	       are not reproducible.  Discard the symbol.  */
11267 	    continue;
11268 	  have_file_sym = true;
11269 	  flinfo->filesym_count += 1;
11270 	}
11271       if (!have_file_sym)
11272 	{
11273 	  /* In the absence of debug info, bfd_find_nearest_line uses
11274 	     FILE symbols to determine the source file for local
11275 	     function symbols.  Provide a FILE symbol here if input
11276 	     files lack such, so that their symbols won't be
11277 	     associated with a previous input file.  It's not the
11278 	     source file, but the best we can do.  */
11279 	  const char *filename;
11280 	  have_file_sym = true;
11281 	  flinfo->filesym_count += 1;
11282 	  memset (&osym, 0, sizeof (osym));
11283 	  osym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
11284 	  osym.st_shndx = SHN_ABS;
11285 	  if (input_bfd->lto_output)
11286 	    filename = NULL;
11287 	  else
11288 	    filename = lbasename (bfd_get_filename (input_bfd));
11289 	  if (!elf_link_output_symstrtab (flinfo, filename, &osym,
11290 					  bfd_abs_section_ptr, NULL))
11291 	    return false;
11292 	}
11293 
11294       osym = *isym;
11295 
11296       /* Adjust the section index for the output file.  */
11297       osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
11298 							 isec->output_section);
11299       if (osym.st_shndx == SHN_BAD)
11300 	return false;
11301 
11302       /* ELF symbols in relocatable files are section relative, but
11303 	 in executable files they are virtual addresses.  Note that
11304 	 this code assumes that all ELF sections have an associated
11305 	 BFD section with a reasonable value for output_offset; below
11306 	 we assume that they also have a reasonable value for
11307 	 output_section.  Any special sections must be set up to meet
11308 	 these requirements.  */
11309       osym.st_value += isec->output_offset;
11310       if (!bfd_link_relocatable (flinfo->info))
11311 	{
11312 	  osym.st_value += isec->output_section->vma;
11313 	  if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
11314 	    {
11315 	      /* STT_TLS symbols are relative to PT_TLS segment base.  */
11316 	      if (elf_hash_table (flinfo->info)->tls_sec != NULL)
11317 		osym.st_value -= elf_hash_table (flinfo->info)->tls_sec->vma;
11318 	      else
11319 		osym.st_info = ELF_ST_INFO (ELF_ST_BIND (osym.st_info),
11320 					    STT_NOTYPE);
11321 	    }
11322 	}
11323 
11324       indx = bfd_get_symcount (output_bfd);
11325       ret = elf_link_output_symstrtab (flinfo, name, &osym, isec, NULL);
11326       if (ret == 0)
11327 	return false;
11328       else if (ret == 1)
11329 	*pindex = indx;
11330     }
11331 
11332   if (bed->s->arch_size == 32)
11333     {
11334       r_type_mask = 0xff;
11335       r_sym_shift = 8;
11336       address_size = 4;
11337     }
11338   else
11339     {
11340       r_type_mask = 0xffffffff;
11341       r_sym_shift = 32;
11342       address_size = 8;
11343     }
11344 
11345   /* Relocate the contents of each section.  */
11346   sym_hashes = elf_sym_hashes (input_bfd);
11347   for (o = input_bfd->sections; o != NULL; o = o->next)
11348     {
11349       bfd_byte *contents;
11350 
11351       if (! o->linker_mark)
11352 	{
11353 	  /* This section was omitted from the link.  */
11354 	  continue;
11355 	}
11356 
11357       if (!flinfo->info->resolve_section_groups
11358 	  && (o->flags & (SEC_LINKER_CREATED | SEC_GROUP)) == SEC_GROUP)
11359 	{
11360 	  /* Deal with the group signature symbol.  */
11361 	  struct bfd_elf_section_data *sec_data = elf_section_data (o);
11362 	  unsigned long symndx = sec_data->this_hdr.sh_info;
11363 	  asection *osec = o->output_section;
11364 
11365 	  BFD_ASSERT (bfd_link_relocatable (flinfo->info));
11366 	  if (symndx >= locsymcount
11367 	      || (elf_bad_symtab (input_bfd)
11368 		  && flinfo->sections[symndx] == NULL))
11369 	    {
11370 	      struct elf_link_hash_entry *h = sym_hashes[symndx - extsymoff];
11371 	      while (h->root.type == bfd_link_hash_indirect
11372 		     || h->root.type == bfd_link_hash_warning)
11373 		h = (struct elf_link_hash_entry *) h->root.u.i.link;
11374 	      /* Arrange for symbol to be output.  */
11375 	      h->indx = -2;
11376 	      elf_section_data (osec)->this_hdr.sh_info = -2;
11377 	    }
11378 	  else if (ELF_ST_TYPE (isymbuf[symndx].st_info) == STT_SECTION)
11379 	    {
11380 	      /* We'll use the output section target_index.  */
11381 	      asection *sec = flinfo->sections[symndx]->output_section;
11382 	      elf_section_data (osec)->this_hdr.sh_info = sec->target_index;
11383 	    }
11384 	  else
11385 	    {
11386 	      if (flinfo->indices[symndx] == -1)
11387 		{
11388 		  /* Otherwise output the local symbol now.  */
11389 		  Elf_Internal_Sym sym = isymbuf[symndx];
11390 		  asection *sec = flinfo->sections[symndx]->output_section;
11391 		  const char *name;
11392 		  long indx;
11393 		  int ret;
11394 
11395 		  name = bfd_elf_string_from_elf_section (input_bfd,
11396 							  symtab_hdr->sh_link,
11397 							  sym.st_name);
11398 		  if (name == NULL)
11399 		    return false;
11400 
11401 		  sym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
11402 								    sec);
11403 		  if (sym.st_shndx == SHN_BAD)
11404 		    return false;
11405 
11406 		  sym.st_value += o->output_offset;
11407 
11408 		  indx = bfd_get_symcount (output_bfd);
11409 		  ret = elf_link_output_symstrtab (flinfo, name, &sym, o,
11410 						   NULL);
11411 		  if (ret == 0)
11412 		    return false;
11413 		  else if (ret == 1)
11414 		    flinfo->indices[symndx] = indx;
11415 		  else
11416 		    abort ();
11417 		}
11418 	      elf_section_data (osec)->this_hdr.sh_info
11419 		= flinfo->indices[symndx];
11420 	    }
11421 	}
11422 
11423       if ((o->flags & SEC_HAS_CONTENTS) == 0
11424 	  || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
11425 	continue;
11426 
11427       if ((o->flags & SEC_LINKER_CREATED) != 0)
11428 	{
11429 	  /* Section was created by _bfd_elf_link_create_dynamic_sections
11430 	     or somesuch.  */
11431 	  continue;
11432 	}
11433 
11434       /* Get the contents of the section.  They have been cached by a
11435 	 relaxation routine.  Note that o is a section in an input
11436 	 file, so the contents field will not have been set by any of
11437 	 the routines which work on output files.  */
11438       if (elf_section_data (o)->this_hdr.contents != NULL)
11439 	{
11440 	  contents = elf_section_data (o)->this_hdr.contents;
11441 	  if (bed->caches_rawsize
11442 	      && o->rawsize != 0
11443 	      && o->rawsize < o->size)
11444 	    {
11445 	      memcpy (flinfo->contents, contents, o->rawsize);
11446 	      contents = flinfo->contents;
11447 	    }
11448 	}
11449       else if (!(o->flags & SEC_RELOC)
11450 	       && !bed->elf_backend_write_section
11451 	       && o->sec_info_type == SEC_INFO_TYPE_MERGE)
11452 	/* A MERGE section that has no relocations doesn't need the
11453 	   contents anymore, they have been recorded earlier.  Except
11454 	   if the backend has special provisions for writing sections.  */
11455 	contents = NULL;
11456       else
11457 	{
11458 	  contents = flinfo->contents;
11459 	  if (! bfd_get_full_section_contents (input_bfd, o, &contents))
11460 	    return false;
11461 	}
11462 
11463       if ((o->flags & SEC_RELOC) != 0)
11464 	{
11465 	  Elf_Internal_Rela *internal_relocs;
11466 	  Elf_Internal_Rela *rel, *relend;
11467 	  int action_discarded;
11468 	  int ret;
11469 
11470 	  /* Get the swapped relocs.  */
11471 	  internal_relocs
11472 	    = _bfd_elf_link_info_read_relocs (input_bfd, flinfo->info, o,
11473 					      flinfo->external_relocs,
11474 					      flinfo->internal_relocs,
11475 					      false);
11476 	  if (internal_relocs == NULL
11477 	      && o->reloc_count > 0)
11478 	    return false;
11479 
11480 	  action_discarded = -1;
11481 	  if (!elf_section_ignore_discarded_relocs (o))
11482 	    action_discarded = (*bed->action_discarded) (o);
11483 
11484 	  /* Run through the relocs evaluating complex reloc symbols and
11485 	     looking for relocs against symbols from discarded sections
11486 	     or section symbols from removed link-once sections.
11487 	     Complain about relocs against discarded sections.  Zero
11488 	     relocs against removed link-once sections.  */
11489 
11490 	  rel = internal_relocs;
11491 	  relend = rel + o->reloc_count;
11492 	  for ( ; rel < relend; rel++)
11493 	    {
11494 	      unsigned long r_symndx = rel->r_info >> r_sym_shift;
11495 	      unsigned int s_type;
11496 	      asection **ps, *sec;
11497 	      struct elf_link_hash_entry *h = NULL;
11498 	      const char *sym_name;
11499 
11500 	      if (r_symndx == STN_UNDEF)
11501 		continue;
11502 
11503 	      if (r_symndx >= locsymcount
11504 		  || (elf_bad_symtab (input_bfd)
11505 		      && flinfo->sections[r_symndx] == NULL))
11506 		{
11507 		  h = sym_hashes[r_symndx - extsymoff];
11508 
11509 		  /* Badly formatted input files can contain relocs that
11510 		     reference non-existant symbols.  Check here so that
11511 		     we do not seg fault.  */
11512 		  if (h == NULL)
11513 		    {
11514 		      _bfd_error_handler
11515 			/* xgettext:c-format */
11516 			(_("error: %pB contains a reloc (%#" PRIx64 ") for section %pA "
11517 			   "that references a non-existent global symbol"),
11518 			 input_bfd, (uint64_t) rel->r_info, o);
11519 		      bfd_set_error (bfd_error_bad_value);
11520 		      return false;
11521 		    }
11522 
11523 		  while (h->root.type == bfd_link_hash_indirect
11524 			 || h->root.type == bfd_link_hash_warning)
11525 		    h = (struct elf_link_hash_entry *) h->root.u.i.link;
11526 
11527 		  s_type = h->type;
11528 
11529 		  /* If a plugin symbol is referenced from a non-IR file,
11530 		     mark the symbol as undefined.  Note that the
11531 		     linker may attach linker created dynamic sections
11532 		     to the plugin bfd.  Symbols defined in linker
11533 		     created sections are not plugin symbols.  */
11534 		  if ((h->root.non_ir_ref_regular
11535 		       || h->root.non_ir_ref_dynamic)
11536 		      && (h->root.type == bfd_link_hash_defined
11537 			  || h->root.type == bfd_link_hash_defweak)
11538 		      && (h->root.u.def.section->flags
11539 			  & SEC_LINKER_CREATED) == 0
11540 		      && h->root.u.def.section->owner != NULL
11541 		      && (h->root.u.def.section->owner->flags
11542 			  & BFD_PLUGIN) != 0)
11543 		    {
11544 		      h->root.type = bfd_link_hash_undefined;
11545 		      h->root.u.undef.abfd = h->root.u.def.section->owner;
11546 		    }
11547 
11548 		  ps = NULL;
11549 		  if (h->root.type == bfd_link_hash_defined
11550 		      || h->root.type == bfd_link_hash_defweak)
11551 		    ps = &h->root.u.def.section;
11552 
11553 		  sym_name = h->root.root.string;
11554 		}
11555 	      else
11556 		{
11557 		  Elf_Internal_Sym *sym = isymbuf + r_symndx;
11558 
11559 		  s_type = ELF_ST_TYPE (sym->st_info);
11560 		  ps = &flinfo->sections[r_symndx];
11561 		  sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr,
11562 					       sym, *ps);
11563 		}
11564 
11565 	      if ((s_type == STT_RELC || s_type == STT_SRELC)
11566 		  && !bfd_link_relocatable (flinfo->info))
11567 		{
11568 		  bfd_vma val;
11569 		  bfd_vma dot = (rel->r_offset
11570 				 + o->output_offset + o->output_section->vma);
11571 #ifdef DEBUG
11572 		  printf ("Encountered a complex symbol!");
11573 		  printf (" (input_bfd %s, section %s, reloc %ld\n",
11574 			  bfd_get_filename (input_bfd), o->name,
11575 			  (long) (rel - internal_relocs));
11576 		  printf (" symbol: idx  %8.8lx, name %s\n",
11577 			  r_symndx, sym_name);
11578 		  printf (" reloc : info %8.8lx, addr %8.8lx\n",
11579 			  (unsigned long) rel->r_info,
11580 			  (unsigned long) rel->r_offset);
11581 #endif
11582 		  if (!eval_symbol (&val, &sym_name, input_bfd, flinfo, dot,
11583 				    isymbuf, locsymcount, s_type == STT_SRELC))
11584 		    return false;
11585 
11586 		  /* Symbol evaluated OK.  Update to absolute value.  */
11587 		  set_symbol_value (input_bfd, isymbuf, locsymcount,
11588 				    r_symndx, val);
11589 		  continue;
11590 		}
11591 
11592 	      if (action_discarded != -1 && ps != NULL)
11593 		{
11594 		  /* Complain if the definition comes from a
11595 		     discarded section.  */
11596 		  if ((sec = *ps) != NULL && discarded_section (sec))
11597 		    {
11598 		      BFD_ASSERT (r_symndx != STN_UNDEF);
11599 		      if (action_discarded & COMPLAIN)
11600 			(*flinfo->info->callbacks->einfo)
11601 			  /* xgettext:c-format */
11602 			  (_("%X`%s' referenced in section `%pA' of %pB: "
11603 			     "defined in discarded section `%pA' of %pB\n"),
11604 			   sym_name, o, input_bfd, sec, sec->owner);
11605 
11606 		      /* Try to do the best we can to support buggy old
11607 			 versions of gcc.  Pretend that the symbol is
11608 			 really defined in the kept linkonce section.
11609 			 FIXME: This is quite broken.  Modifying the
11610 			 symbol here means we will be changing all later
11611 			 uses of the symbol, not just in this section.  */
11612 		      if (action_discarded & PRETEND)
11613 			{
11614 			  asection *kept;
11615 
11616 			  kept = _bfd_elf_check_kept_section (sec,
11617 							      flinfo->info);
11618 			  if (kept != NULL)
11619 			    {
11620 			      *ps = kept;
11621 			      continue;
11622 			    }
11623 			}
11624 		    }
11625 		}
11626 	    }
11627 
11628 	  /* Relocate the section by invoking a back end routine.
11629 
11630 	     The back end routine is responsible for adjusting the
11631 	     section contents as necessary, and (if using Rela relocs
11632 	     and generating a relocatable output file) adjusting the
11633 	     reloc addend as necessary.
11634 
11635 	     The back end routine does not have to worry about setting
11636 	     the reloc address or the reloc symbol index.
11637 
11638 	     The back end routine is given a pointer to the swapped in
11639 	     internal symbols, and can access the hash table entries
11640 	     for the external symbols via elf_sym_hashes (input_bfd).
11641 
11642 	     When generating relocatable output, the back end routine
11643 	     must handle STB_LOCAL/STT_SECTION symbols specially.  The
11644 	     output symbol is going to be a section symbol
11645 	     corresponding to the output section, which will require
11646 	     the addend to be adjusted.  */
11647 
11648 	  ret = (*relocate_section) (output_bfd, flinfo->info,
11649 				     input_bfd, o, contents,
11650 				     internal_relocs,
11651 				     isymbuf,
11652 				     flinfo->sections);
11653 	  if (!ret)
11654 	    return false;
11655 
11656 	  if (ret == 2
11657 	      || bfd_link_relocatable (flinfo->info)
11658 	      || flinfo->info->emitrelocations)
11659 	    {
11660 	      Elf_Internal_Rela *irela;
11661 	      Elf_Internal_Rela *irelaend, *irelamid;
11662 	      bfd_vma last_offset;
11663 	      struct elf_link_hash_entry **rel_hash;
11664 	      struct elf_link_hash_entry **rel_hash_list, **rela_hash_list;
11665 	      Elf_Internal_Shdr *input_rel_hdr, *input_rela_hdr;
11666 	      unsigned int next_erel;
11667 	      bool rela_normal;
11668 	      struct bfd_elf_section_data *esdi, *esdo;
11669 
11670 	      esdi = elf_section_data (o);
11671 	      esdo = elf_section_data (o->output_section);
11672 	      rela_normal = false;
11673 
11674 	      /* Adjust the reloc addresses and symbol indices.  */
11675 
11676 	      irela = internal_relocs;
11677 	      irelaend = irela + o->reloc_count;
11678 	      rel_hash = PTR_ADD (esdo->rel.hashes, esdo->rel.count);
11679 	      /* We start processing the REL relocs, if any.  When we reach
11680 		 IRELAMID in the loop, we switch to the RELA relocs.  */
11681 	      irelamid = irela;
11682 	      if (esdi->rel.hdr != NULL)
11683 		irelamid += (NUM_SHDR_ENTRIES (esdi->rel.hdr)
11684 			     * bed->s->int_rels_per_ext_rel);
11685 	      rel_hash_list = rel_hash;
11686 	      rela_hash_list = NULL;
11687 	      last_offset = o->output_offset;
11688 	      if (!bfd_link_relocatable (flinfo->info))
11689 		last_offset += o->output_section->vma;
11690 	      for (next_erel = 0; irela < irelaend; irela++, next_erel++)
11691 		{
11692 		  unsigned long r_symndx;
11693 		  asection *sec;
11694 		  Elf_Internal_Sym sym;
11695 
11696 		  if (next_erel == bed->s->int_rels_per_ext_rel)
11697 		    {
11698 		      rel_hash++;
11699 		      next_erel = 0;
11700 		    }
11701 
11702 		  if (irela == irelamid)
11703 		    {
11704 		      rel_hash = PTR_ADD (esdo->rela.hashes, esdo->rela.count);
11705 		      rela_hash_list = rel_hash;
11706 		      rela_normal = bed->rela_normal;
11707 		    }
11708 
11709 		  irela->r_offset = _bfd_elf_section_offset (output_bfd,
11710 							     flinfo->info, o,
11711 							     irela->r_offset);
11712 		  if (irela->r_offset >= (bfd_vma) -2)
11713 		    {
11714 		      /* This is a reloc for a deleted entry or somesuch.
11715 			 Turn it into an R_*_NONE reloc, at the same
11716 			 offset as the last reloc.  elf_eh_frame.c and
11717 			 bfd_elf_discard_info rely on reloc offsets
11718 			 being ordered.  */
11719 		      irela->r_offset = last_offset;
11720 		      irela->r_info = 0;
11721 		      irela->r_addend = 0;
11722 		      continue;
11723 		    }
11724 
11725 		  irela->r_offset += o->output_offset;
11726 
11727 		  /* Relocs in an executable have to be virtual addresses.  */
11728 		  if (!bfd_link_relocatable (flinfo->info))
11729 		    irela->r_offset += o->output_section->vma;
11730 
11731 		  last_offset = irela->r_offset;
11732 
11733 		  r_symndx = irela->r_info >> r_sym_shift;
11734 		  if (r_symndx == STN_UNDEF)
11735 		    continue;
11736 
11737 		  if (r_symndx >= locsymcount
11738 		      || (elf_bad_symtab (input_bfd)
11739 			  && flinfo->sections[r_symndx] == NULL))
11740 		    {
11741 		      struct elf_link_hash_entry *rh;
11742 		      unsigned long indx;
11743 
11744 		      /* This is a reloc against a global symbol.  We
11745 			 have not yet output all the local symbols, so
11746 			 we do not know the symbol index of any global
11747 			 symbol.  We set the rel_hash entry for this
11748 			 reloc to point to the global hash table entry
11749 			 for this symbol.  The symbol index is then
11750 			 set at the end of bfd_elf_final_link.  */
11751 		      indx = r_symndx - extsymoff;
11752 		      rh = elf_sym_hashes (input_bfd)[indx];
11753 		      while (rh->root.type == bfd_link_hash_indirect
11754 			     || rh->root.type == bfd_link_hash_warning)
11755 			rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
11756 
11757 		      /* Setting the index to -2 tells
11758 			 elf_link_output_extsym that this symbol is
11759 			 used by a reloc.  */
11760 		      BFD_ASSERT (rh->indx < 0);
11761 		      rh->indx = -2;
11762 		      *rel_hash = rh;
11763 
11764 		      continue;
11765 		    }
11766 
11767 		  /* This is a reloc against a local symbol.  */
11768 
11769 		  *rel_hash = NULL;
11770 		  sym = isymbuf[r_symndx];
11771 		  sec = flinfo->sections[r_symndx];
11772 		  if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
11773 		    {
11774 		      /* I suppose the backend ought to fill in the
11775 			 section of any STT_SECTION symbol against a
11776 			 processor specific section.  */
11777 		      r_symndx = STN_UNDEF;
11778 		      if (bfd_is_abs_section (sec))
11779 			;
11780 		      else if (sec == NULL || sec->owner == NULL)
11781 			{
11782 			  bfd_set_error (bfd_error_bad_value);
11783 			  return false;
11784 			}
11785 		      else
11786 			{
11787 			  asection *osec = sec->output_section;
11788 
11789 			  /* If we have discarded a section, the output
11790 			     section will be the absolute section.  In
11791 			     case of discarded SEC_MERGE sections, use
11792 			     the kept section.  relocate_section should
11793 			     have already handled discarded linkonce
11794 			     sections.  */
11795 			  if (bfd_is_abs_section (osec)
11796 			      && sec->kept_section != NULL
11797 			      && sec->kept_section->output_section != NULL)
11798 			    {
11799 			      osec = sec->kept_section->output_section;
11800 			      irela->r_addend -= osec->vma;
11801 			    }
11802 
11803 			  if (!bfd_is_abs_section (osec))
11804 			    {
11805 			      r_symndx = osec->target_index;
11806 			      if (r_symndx == STN_UNDEF)
11807 				{
11808 				  irela->r_addend += osec->vma;
11809 				  osec = _bfd_nearby_section (output_bfd, osec,
11810 							      osec->vma);
11811 				  irela->r_addend -= osec->vma;
11812 				  r_symndx = osec->target_index;
11813 				}
11814 			    }
11815 			}
11816 
11817 		      /* Adjust the addend according to where the
11818 			 section winds up in the output section.  */
11819 		      if (rela_normal)
11820 			irela->r_addend += sec->output_offset;
11821 		    }
11822 		  else
11823 		    {
11824 		      if (flinfo->indices[r_symndx] == -1)
11825 			{
11826 			  unsigned long shlink;
11827 			  const char *name;
11828 			  asection *osec;
11829 			  long indx;
11830 
11831 			  if (flinfo->info->strip == strip_all)
11832 			    {
11833 			      /* You can't do ld -r -s.  */
11834 			      bfd_set_error (bfd_error_invalid_operation);
11835 			      return false;
11836 			    }
11837 
11838 			  /* This symbol was skipped earlier, but
11839 			     since it is needed by a reloc, we
11840 			     must output it now.  */
11841 			  shlink = symtab_hdr->sh_link;
11842 			  name = (bfd_elf_string_from_elf_section
11843 				  (input_bfd, shlink, sym.st_name));
11844 			  if (name == NULL)
11845 			    return false;
11846 
11847 			  osec = sec->output_section;
11848 			  sym.st_shndx =
11849 			    _bfd_elf_section_from_bfd_section (output_bfd,
11850 							       osec);
11851 			  if (sym.st_shndx == SHN_BAD)
11852 			    return false;
11853 
11854 			  sym.st_value += sec->output_offset;
11855 			  if (!bfd_link_relocatable (flinfo->info))
11856 			    {
11857 			      sym.st_value += osec->vma;
11858 			      if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
11859 				{
11860 				  struct elf_link_hash_table *htab
11861 				    = elf_hash_table (flinfo->info);
11862 
11863 				  /* STT_TLS symbols are relative to PT_TLS
11864 				     segment base.  */
11865 				  if (htab->tls_sec != NULL)
11866 				    sym.st_value -= htab->tls_sec->vma;
11867 				  else
11868 				    sym.st_info
11869 				      = ELF_ST_INFO (ELF_ST_BIND (sym.st_info),
11870 						     STT_NOTYPE);
11871 				}
11872 			    }
11873 
11874 			  indx = bfd_get_symcount (output_bfd);
11875 			  ret = elf_link_output_symstrtab (flinfo, name,
11876 							   &sym, sec,
11877 							   NULL);
11878 			  if (ret == 0)
11879 			    return false;
11880 			  else if (ret == 1)
11881 			    flinfo->indices[r_symndx] = indx;
11882 			  else
11883 			    abort ();
11884 			}
11885 
11886 		      r_symndx = flinfo->indices[r_symndx];
11887 		    }
11888 
11889 		  irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
11890 				   | (irela->r_info & r_type_mask));
11891 		}
11892 
11893 	      /* Swap out the relocs.  */
11894 	      input_rel_hdr = esdi->rel.hdr;
11895 	      if (input_rel_hdr && input_rel_hdr->sh_size != 0)
11896 		{
11897 		  if (!bed->elf_backend_emit_relocs (output_bfd, o,
11898 						     input_rel_hdr,
11899 						     internal_relocs,
11900 						     rel_hash_list))
11901 		    return false;
11902 		  internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
11903 				      * bed->s->int_rels_per_ext_rel);
11904 		  rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
11905 		}
11906 
11907 	      input_rela_hdr = esdi->rela.hdr;
11908 	      if (input_rela_hdr && input_rela_hdr->sh_size != 0)
11909 		{
11910 		  if (!bed->elf_backend_emit_relocs (output_bfd, o,
11911 						     input_rela_hdr,
11912 						     internal_relocs,
11913 						     rela_hash_list))
11914 		    return false;
11915 		}
11916 	    }
11917 	}
11918 
11919       /* Write out the modified section contents.  */
11920       if (bed->elf_backend_write_section
11921 	  && (*bed->elf_backend_write_section) (output_bfd, flinfo->info, o,
11922 						contents))
11923 	{
11924 	  /* Section written out.  */
11925 	}
11926       else switch (o->sec_info_type)
11927 	{
11928 	case SEC_INFO_TYPE_STABS:
11929 	  if (! (_bfd_write_section_stabs
11930 		 (output_bfd,
11931 		  &elf_hash_table (flinfo->info)->stab_info,
11932 		  o, &elf_section_data (o)->sec_info, contents)))
11933 	    return false;
11934 	  break;
11935 	case SEC_INFO_TYPE_MERGE:
11936 	  if (! _bfd_write_merged_section (output_bfd, o,
11937 					   elf_section_data (o)->sec_info))
11938 	    return false;
11939 	  break;
11940 	case SEC_INFO_TYPE_EH_FRAME:
11941 	  {
11942 	    if (! _bfd_elf_write_section_eh_frame (output_bfd, flinfo->info,
11943 						   o, contents))
11944 	      return false;
11945 	  }
11946 	  break;
11947 	case SEC_INFO_TYPE_EH_FRAME_ENTRY:
11948 	  {
11949 	    if (! _bfd_elf_write_section_eh_frame_entry (output_bfd,
11950 							 flinfo->info,
11951 							 o, contents))
11952 	      return false;
11953 	  }
11954 	  break;
11955 	case SEC_INFO_TYPE_SFRAME:
11956 	    {
11957 	      /* Merge .sframe sections into the ctf frame encoder
11958 		 context of the output_bfd's section.  The final .sframe
11959 		 output section will be written out later.  */
11960 	      if (!_bfd_elf_merge_section_sframe (output_bfd, flinfo->info,
11961 						  o, contents))
11962 		return false;
11963 	    }
11964 	    break;
11965 	default:
11966 	  {
11967 	    if (! (o->flags & SEC_EXCLUDE))
11968 	      {
11969 		file_ptr offset = (file_ptr) o->output_offset;
11970 		bfd_size_type todo = o->size;
11971 
11972 		offset *= bfd_octets_per_byte (output_bfd, o);
11973 
11974 		if ((o->flags & SEC_ELF_REVERSE_COPY)
11975 		    && o->size > address_size)
11976 		  {
11977 		    /* Reverse-copy input section to output.  */
11978 
11979 		    if ((o->size & (address_size - 1)) != 0
11980 			|| (o->reloc_count != 0
11981 			    && (o->size * bed->s->int_rels_per_ext_rel
11982 				!= o->reloc_count * address_size)))
11983 		      {
11984 			_bfd_error_handler
11985 			  /* xgettext:c-format */
11986 			  (_("error: %pB: size of section %pA is not "
11987 			     "multiple of address size"),
11988 			   input_bfd, o);
11989 			bfd_set_error (bfd_error_bad_value);
11990 			return false;
11991 		      }
11992 
11993 		    do
11994 		      {
11995 			todo -= address_size;
11996 			if (! bfd_set_section_contents (output_bfd,
11997 							o->output_section,
11998 							contents + todo,
11999 							offset,
12000 							address_size))
12001 			  return false;
12002 			if (todo == 0)
12003 			  break;
12004 			offset += address_size;
12005 		      }
12006 		    while (1);
12007 		  }
12008 		else if (! bfd_set_section_contents (output_bfd,
12009 						     o->output_section,
12010 						     contents,
12011 						     offset, todo))
12012 		  return false;
12013 	      }
12014 	  }
12015 	  break;
12016 	}
12017     }
12018 
12019   return true;
12020 }
12021 
12022 /* Generate a reloc when linking an ELF file.  This is a reloc
12023    requested by the linker, and does not come from any input file.  This
12024    is used to build constructor and destructor tables when linking
12025    with -Ur.  */
12026 
12027 static bool
elf_reloc_link_order(bfd * output_bfd,struct bfd_link_info * info,asection * output_section,struct bfd_link_order * link_order)12028 elf_reloc_link_order (bfd *output_bfd,
12029 		      struct bfd_link_info *info,
12030 		      asection *output_section,
12031 		      struct bfd_link_order *link_order)
12032 {
12033   reloc_howto_type *howto;
12034   long indx;
12035   bfd_vma offset;
12036   bfd_vma addend;
12037   struct bfd_elf_section_reloc_data *reldata;
12038   struct elf_link_hash_entry **rel_hash_ptr;
12039   Elf_Internal_Shdr *rel_hdr;
12040   const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
12041   Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
12042   bfd_byte *erel;
12043   unsigned int i;
12044   struct bfd_elf_section_data *esdo = elf_section_data (output_section);
12045 
12046   howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
12047   if (howto == NULL)
12048     {
12049       bfd_set_error (bfd_error_bad_value);
12050       return false;
12051     }
12052 
12053   addend = link_order->u.reloc.p->addend;
12054 
12055   if (esdo->rel.hdr)
12056     reldata = &esdo->rel;
12057   else if (esdo->rela.hdr)
12058     reldata = &esdo->rela;
12059   else
12060     {
12061       reldata = NULL;
12062       BFD_ASSERT (0);
12063     }
12064 
12065   /* Figure out the symbol index.  */
12066   rel_hash_ptr = reldata->hashes + reldata->count;
12067   if (link_order->type == bfd_section_reloc_link_order)
12068     {
12069       indx = link_order->u.reloc.p->u.section->target_index;
12070       BFD_ASSERT (indx != 0);
12071       *rel_hash_ptr = NULL;
12072     }
12073   else
12074     {
12075       struct elf_link_hash_entry *h;
12076 
12077       /* Treat a reloc against a defined symbol as though it were
12078 	 actually against the section.  */
12079       h = ((struct elf_link_hash_entry *)
12080 	   bfd_wrapped_link_hash_lookup (output_bfd, info,
12081 					 link_order->u.reloc.p->u.name,
12082 					 false, false, true));
12083       if (h != NULL
12084 	  && (h->root.type == bfd_link_hash_defined
12085 	      || h->root.type == bfd_link_hash_defweak))
12086 	{
12087 	  asection *section;
12088 
12089 	  section = h->root.u.def.section;
12090 	  indx = section->output_section->target_index;
12091 	  *rel_hash_ptr = NULL;
12092 	  /* It seems that we ought to add the symbol value to the
12093 	     addend here, but in practice it has already been added
12094 	     because it was passed to constructor_callback.  */
12095 	  addend += section->output_section->vma + section->output_offset;
12096 	}
12097       else if (h != NULL)
12098 	{
12099 	  /* Setting the index to -2 tells elf_link_output_extsym that
12100 	     this symbol is used by a reloc.  */
12101 	  h->indx = -2;
12102 	  *rel_hash_ptr = h;
12103 	  indx = 0;
12104 	}
12105       else
12106 	{
12107 	  (*info->callbacks->unattached_reloc)
12108 	    (info, link_order->u.reloc.p->u.name, NULL, NULL, 0);
12109 	  indx = 0;
12110 	}
12111     }
12112 
12113   /* If this is an inplace reloc, we must write the addend into the
12114      object file.  */
12115   if (howto->partial_inplace && addend != 0)
12116     {
12117       bfd_size_type size;
12118       bfd_reloc_status_type rstat;
12119       bfd_byte *buf;
12120       bool ok;
12121       const char *sym_name;
12122       bfd_size_type octets;
12123 
12124       size = (bfd_size_type) bfd_get_reloc_size (howto);
12125       buf = (bfd_byte *) bfd_zmalloc (size);
12126       if (buf == NULL && size != 0)
12127 	return false;
12128       rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
12129       switch (rstat)
12130 	{
12131 	case bfd_reloc_ok:
12132 	  break;
12133 
12134 	default:
12135 	case bfd_reloc_outofrange:
12136 	  abort ();
12137 
12138 	case bfd_reloc_overflow:
12139 	  if (link_order->type == bfd_section_reloc_link_order)
12140 	    sym_name = bfd_section_name (link_order->u.reloc.p->u.section);
12141 	  else
12142 	    sym_name = link_order->u.reloc.p->u.name;
12143 	  (*info->callbacks->reloc_overflow) (info, NULL, sym_name,
12144 					      howto->name, addend, NULL, NULL,
12145 					      (bfd_vma) 0);
12146 	  break;
12147 	}
12148 
12149       octets = link_order->offset * bfd_octets_per_byte (output_bfd,
12150 							 output_section);
12151       ok = bfd_set_section_contents (output_bfd, output_section, buf,
12152 				     octets, size);
12153       free (buf);
12154       if (! ok)
12155 	return false;
12156     }
12157 
12158   /* The address of a reloc is relative to the section in a
12159      relocatable file, and is a virtual address in an executable
12160      file.  */
12161   offset = link_order->offset;
12162   if (! bfd_link_relocatable (info))
12163     offset += output_section->vma;
12164 
12165   for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
12166     {
12167       irel[i].r_offset = offset;
12168       irel[i].r_info = 0;
12169       irel[i].r_addend = 0;
12170     }
12171   if (bed->s->arch_size == 32)
12172     irel[0].r_info = ELF32_R_INFO (indx, howto->type);
12173   else
12174 #ifdef BFD64
12175     irel[0].r_info = ELF64_R_INFO (indx, howto->type);
12176 #else
12177     BFD_FAIL();
12178 #endif
12179 
12180   rel_hdr = reldata->hdr;
12181   erel = rel_hdr->contents;
12182   if (rel_hdr->sh_type == SHT_REL)
12183     {
12184       erel += reldata->count * bed->s->sizeof_rel;
12185       (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
12186     }
12187   else
12188     {
12189       irel[0].r_addend = addend;
12190       erel += reldata->count * bed->s->sizeof_rela;
12191       (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
12192     }
12193 
12194   ++reldata->count;
12195 
12196   return true;
12197 }
12198 
12199 /* Generate an import library in INFO->implib_bfd from symbols in ABFD.
12200    Returns TRUE upon success, FALSE otherwise.  */
12201 
12202 static bool
elf_output_implib(bfd * abfd,struct bfd_link_info * info)12203 elf_output_implib (bfd *abfd, struct bfd_link_info *info)
12204 {
12205   bool ret = false;
12206   bfd *implib_bfd;
12207   const struct elf_backend_data *bed;
12208   flagword flags;
12209   enum bfd_architecture arch;
12210   unsigned int mach;
12211   asymbol **sympp = NULL;
12212   long symsize;
12213   long symcount;
12214   long src_count;
12215   elf_symbol_type *osymbuf;
12216   size_t amt;
12217 
12218   implib_bfd = info->out_implib_bfd;
12219   bed = get_elf_backend_data (abfd);
12220 
12221   if (!bfd_set_format (implib_bfd, bfd_object))
12222     return false;
12223 
12224   /* Use flag from executable but make it a relocatable object.  */
12225   flags = bfd_get_file_flags (abfd);
12226   flags &= ~HAS_RELOC;
12227   if (!bfd_set_start_address (implib_bfd, 0)
12228       || !bfd_set_file_flags (implib_bfd, flags & ~EXEC_P))
12229     return false;
12230 
12231   /* Copy architecture of output file to import library file.  */
12232   arch = bfd_get_arch (abfd);
12233   mach = bfd_get_mach (abfd);
12234   if (!bfd_set_arch_mach (implib_bfd, arch, mach)
12235       && (abfd->target_defaulted
12236 	  || bfd_get_arch (abfd) != bfd_get_arch (implib_bfd)))
12237     return false;
12238 
12239   /* Get symbol table size.  */
12240   symsize = bfd_get_symtab_upper_bound (abfd);
12241   if (symsize < 0)
12242     return false;
12243 
12244   /* Read in the symbol table.  */
12245   sympp = (asymbol **) bfd_malloc (symsize);
12246   if (sympp == NULL)
12247     return false;
12248 
12249   symcount = bfd_canonicalize_symtab (abfd, sympp);
12250   if (symcount < 0)
12251     goto free_sym_buf;
12252 
12253   /* Allow the BFD backend to copy any private header data it
12254      understands from the output BFD to the import library BFD.  */
12255   if (! bfd_copy_private_header_data (abfd, implib_bfd))
12256     goto free_sym_buf;
12257 
12258   /* Filter symbols to appear in the import library.  */
12259   if (bed->elf_backend_filter_implib_symbols)
12260     symcount = bed->elf_backend_filter_implib_symbols (abfd, info, sympp,
12261 						       symcount);
12262   else
12263     symcount = _bfd_elf_filter_global_symbols (abfd, info, sympp, symcount);
12264   if (symcount == 0)
12265     {
12266       bfd_set_error (bfd_error_no_symbols);
12267       _bfd_error_handler (_("%pB: no symbol found for import library"),
12268 			  implib_bfd);
12269       goto free_sym_buf;
12270     }
12271 
12272 
12273   /* Make symbols absolute.  */
12274   amt = symcount * sizeof (*osymbuf);
12275   osymbuf = (elf_symbol_type *) bfd_alloc (implib_bfd, amt);
12276   if (osymbuf == NULL)
12277     goto free_sym_buf;
12278 
12279   for (src_count = 0; src_count < symcount; src_count++)
12280     {
12281       memcpy (&osymbuf[src_count], (elf_symbol_type *) sympp[src_count],
12282 	      sizeof (*osymbuf));
12283       osymbuf[src_count].symbol.section = bfd_abs_section_ptr;
12284       osymbuf[src_count].internal_elf_sym.st_shndx = SHN_ABS;
12285       osymbuf[src_count].symbol.value += sympp[src_count]->section->vma;
12286       osymbuf[src_count].internal_elf_sym.st_value =
12287 	osymbuf[src_count].symbol.value;
12288       sympp[src_count] = &osymbuf[src_count].symbol;
12289     }
12290 
12291   bfd_set_symtab (implib_bfd, sympp, symcount);
12292 
12293   /* Allow the BFD backend to copy any private data it understands
12294      from the output BFD to the import library BFD.  This is done last
12295      to permit the routine to look at the filtered symbol table.  */
12296   if (! bfd_copy_private_bfd_data (abfd, implib_bfd))
12297     goto free_sym_buf;
12298 
12299   if (!bfd_close (implib_bfd))
12300     goto free_sym_buf;
12301 
12302   ret = true;
12303 
12304  free_sym_buf:
12305   free (sympp);
12306   return ret;
12307 }
12308 
12309 static void
elf_final_link_free(bfd * obfd,struct elf_final_link_info * flinfo)12310 elf_final_link_free (bfd *obfd, struct elf_final_link_info *flinfo)
12311 {
12312   asection *o;
12313 
12314   if (flinfo->symstrtab != NULL)
12315     _bfd_elf_strtab_free (flinfo->symstrtab);
12316   free (flinfo->contents);
12317   free (flinfo->external_relocs);
12318   free (flinfo->internal_relocs);
12319   free (flinfo->external_syms);
12320   free (flinfo->locsym_shndx);
12321   free (flinfo->internal_syms);
12322   free (flinfo->indices);
12323   free (flinfo->sections);
12324   if (flinfo->symshndxbuf != (Elf_External_Sym_Shndx *) -1)
12325     free (flinfo->symshndxbuf);
12326   for (o = obfd->sections; o != NULL; o = o->next)
12327     {
12328       struct bfd_elf_section_data *esdo = elf_section_data (o);
12329       free (esdo->rel.hashes);
12330       free (esdo->rela.hashes);
12331     }
12332 }
12333 
12334 /* Do the final step of an ELF link.  */
12335 
12336 bool
bfd_elf_final_link(bfd * abfd,struct bfd_link_info * info)12337 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
12338 {
12339   bool dynamic;
12340   bool emit_relocs;
12341   bfd *dynobj;
12342   struct elf_final_link_info flinfo;
12343   asection *o;
12344   struct bfd_link_order *p;
12345   bfd *sub;
12346   bfd_size_type max_contents_size;
12347   bfd_size_type max_external_reloc_size;
12348   bfd_size_type max_internal_reloc_count;
12349   bfd_size_type max_sym_count;
12350   bfd_size_type max_sym_shndx_count;
12351   Elf_Internal_Sym elfsym;
12352   unsigned int i;
12353   Elf_Internal_Shdr *symtab_hdr;
12354   Elf_Internal_Shdr *symtab_shndx_hdr;
12355   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
12356   struct elf_outext_info eoinfo;
12357   bool merged;
12358   size_t relativecount;
12359   size_t relr_entsize;
12360   asection *reldyn = 0;
12361   bfd_size_type amt;
12362   asection *attr_section = NULL;
12363   bfd_vma attr_size = 0;
12364   const char *std_attrs_section;
12365   struct elf_link_hash_table *htab = elf_hash_table (info);
12366   bool sections_removed;
12367   bool ret;
12368 
12369   if (!is_elf_hash_table (&htab->root))
12370     return false;
12371 
12372   if (bfd_link_pic (info))
12373     abfd->flags |= DYNAMIC;
12374 
12375   dynamic = htab->dynamic_sections_created;
12376   dynobj = htab->dynobj;
12377 
12378   emit_relocs = (bfd_link_relocatable (info)
12379 		 || info->emitrelocations);
12380 
12381   memset (&flinfo, 0, sizeof (flinfo));
12382   flinfo.info = info;
12383   flinfo.output_bfd = abfd;
12384   flinfo.symstrtab = _bfd_elf_strtab_init ();
12385   if (flinfo.symstrtab == NULL)
12386     return false;
12387 
12388   if (! dynamic)
12389     {
12390       flinfo.hash_sec = NULL;
12391       flinfo.symver_sec = NULL;
12392     }
12393   else
12394     {
12395       flinfo.hash_sec = bfd_get_linker_section (dynobj, ".hash");
12396       /* Note that dynsym_sec can be NULL (on VMS).  */
12397       flinfo.symver_sec = bfd_get_linker_section (dynobj, ".gnu.version");
12398       /* Note that it is OK if symver_sec is NULL.  */
12399     }
12400 
12401   if (info->unique_symbol
12402       && !bfd_hash_table_init (&flinfo.local_hash_table,
12403 			       local_hash_newfunc,
12404 			       sizeof (struct local_hash_entry)))
12405     return false;
12406 
12407   /* The object attributes have been merged.  Remove the input
12408      sections from the link, and set the contents of the output
12409      section.  */
12410   sections_removed = false;
12411   std_attrs_section = get_elf_backend_data (abfd)->obj_attrs_section;
12412   for (o = abfd->sections; o != NULL; o = o->next)
12413     {
12414       bool remove_section = false;
12415 
12416       if ((std_attrs_section && strcmp (o->name, std_attrs_section) == 0)
12417 	  || strcmp (o->name, ".gnu.attributes") == 0)
12418 	{
12419 	  for (p = o->map_head.link_order; p != NULL; p = p->next)
12420 	    {
12421 	      asection *input_section;
12422 
12423 	      if (p->type != bfd_indirect_link_order)
12424 		continue;
12425 	      input_section = p->u.indirect.section;
12426 	      /* Hack: reset the SEC_HAS_CONTENTS flag so that
12427 		 elf_link_input_bfd ignores this section.  */
12428 	      input_section->flags &= ~SEC_HAS_CONTENTS;
12429 	    }
12430 
12431 	  attr_size = bfd_elf_obj_attr_size (abfd);
12432 	  bfd_set_section_size (o, attr_size);
12433 	  /* Skip this section later on.  */
12434 	  o->map_head.link_order = NULL;
12435 	  if (attr_size)
12436 	    attr_section = o;
12437 	  else
12438 	    remove_section = true;
12439 	}
12440       else if ((o->flags & SEC_GROUP) != 0 && o->size == 0)
12441 	{
12442 	  /* Remove empty group section from linker output.  */
12443 	  remove_section = true;
12444 	}
12445       if (remove_section)
12446 	{
12447 	  o->flags |= SEC_EXCLUDE;
12448 	  bfd_section_list_remove (abfd, o);
12449 	  abfd->section_count--;
12450 	  sections_removed = true;
12451 	}
12452     }
12453   if (sections_removed)
12454     _bfd_fix_excluded_sec_syms (abfd, info);
12455 
12456   /* Count up the number of relocations we will output for each output
12457      section, so that we know the sizes of the reloc sections.  We
12458      also figure out some maximum sizes.  */
12459   max_contents_size = 0;
12460   max_external_reloc_size = 0;
12461   max_internal_reloc_count = 0;
12462   max_sym_count = 0;
12463   max_sym_shndx_count = 0;
12464   merged = false;
12465   for (o = abfd->sections; o != NULL; o = o->next)
12466     {
12467       struct bfd_elf_section_data *esdo = elf_section_data (o);
12468       o->reloc_count = 0;
12469 
12470       for (p = o->map_head.link_order; p != NULL; p = p->next)
12471 	{
12472 	  unsigned int reloc_count = 0;
12473 	  unsigned int additional_reloc_count = 0;
12474 	  struct bfd_elf_section_data *esdi = NULL;
12475 
12476 	  if (p->type == bfd_section_reloc_link_order
12477 	      || p->type == bfd_symbol_reloc_link_order)
12478 	    reloc_count = 1;
12479 	  else if (p->type == bfd_indirect_link_order)
12480 	    {
12481 	      asection *sec;
12482 
12483 	      sec = p->u.indirect.section;
12484 
12485 	      /* Mark all sections which are to be included in the
12486 		 link.  This will normally be every section.  We need
12487 		 to do this so that we can identify any sections which
12488 		 the linker has decided to not include.  */
12489 	      sec->linker_mark = true;
12490 
12491 	      if (sec->flags & SEC_MERGE)
12492 		merged = true;
12493 
12494 	      if (sec->rawsize > max_contents_size)
12495 		max_contents_size = sec->rawsize;
12496 	      if (sec->size > max_contents_size)
12497 		max_contents_size = sec->size;
12498 
12499 	      if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
12500 		  && (sec->owner->flags & DYNAMIC) == 0)
12501 		{
12502 		  size_t sym_count;
12503 
12504 		  /* We are interested in just local symbols, not all
12505 		     symbols.  */
12506 		  if (elf_bad_symtab (sec->owner))
12507 		    sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
12508 				 / bed->s->sizeof_sym);
12509 		  else
12510 		    sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
12511 
12512 		  if (sym_count > max_sym_count)
12513 		    max_sym_count = sym_count;
12514 
12515 		  if (sym_count > max_sym_shndx_count
12516 		      && elf_symtab_shndx_list (sec->owner) != NULL)
12517 		    max_sym_shndx_count = sym_count;
12518 
12519 		  esdi = elf_section_data (sec);
12520 
12521 		  if (esdi->this_hdr.sh_type == SHT_REL
12522 		      || esdi->this_hdr.sh_type == SHT_RELA)
12523 		    /* Some backends use reloc_count in relocation sections
12524 		       to count particular types of relocs.  Of course,
12525 		       reloc sections themselves can't have relocations.  */
12526 		    ;
12527 		  else if (emit_relocs)
12528 		    {
12529 		      reloc_count = sec->reloc_count;
12530 		      if (bed->elf_backend_count_additional_relocs)
12531 			{
12532 			  int c;
12533 			  c = (*bed->elf_backend_count_additional_relocs) (sec);
12534 			  additional_reloc_count += c;
12535 			}
12536 		    }
12537 		  else if (bed->elf_backend_count_relocs)
12538 		    reloc_count = (*bed->elf_backend_count_relocs) (info, sec);
12539 
12540 		  if ((sec->flags & SEC_RELOC) != 0)
12541 		    {
12542 		      size_t ext_size = 0;
12543 
12544 		      if (esdi->rel.hdr != NULL)
12545 			ext_size = esdi->rel.hdr->sh_size;
12546 		      if (esdi->rela.hdr != NULL)
12547 			ext_size += esdi->rela.hdr->sh_size;
12548 
12549 		      if (ext_size > max_external_reloc_size)
12550 			max_external_reloc_size = ext_size;
12551 		      if (sec->reloc_count > max_internal_reloc_count)
12552 			max_internal_reloc_count = sec->reloc_count;
12553 		    }
12554 		}
12555 	    }
12556 
12557 	  if (reloc_count == 0)
12558 	    continue;
12559 
12560 	  reloc_count += additional_reloc_count;
12561 	  o->reloc_count += reloc_count;
12562 
12563 	  if (p->type == bfd_indirect_link_order && emit_relocs)
12564 	    {
12565 	      if (esdi->rel.hdr)
12566 		{
12567 		  esdo->rel.count += NUM_SHDR_ENTRIES (esdi->rel.hdr);
12568 		  esdo->rel.count += additional_reloc_count;
12569 		}
12570 	      if (esdi->rela.hdr)
12571 		{
12572 		  esdo->rela.count += NUM_SHDR_ENTRIES (esdi->rela.hdr);
12573 		  esdo->rela.count += additional_reloc_count;
12574 		}
12575 	    }
12576 	  else
12577 	    {
12578 	      if (o->use_rela_p)
12579 		esdo->rela.count += reloc_count;
12580 	      else
12581 		esdo->rel.count += reloc_count;
12582 	    }
12583 	}
12584 
12585       if (o->reloc_count > 0)
12586 	o->flags |= SEC_RELOC;
12587       else
12588 	{
12589 	  /* Explicitly clear the SEC_RELOC flag.  The linker tends to
12590 	     set it (this is probably a bug) and if it is set
12591 	     assign_section_numbers will create a reloc section.  */
12592 	  o->flags &=~ SEC_RELOC;
12593 	}
12594 
12595       /* If the SEC_ALLOC flag is not set, force the section VMA to
12596 	 zero.  This is done in elf_fake_sections as well, but forcing
12597 	 the VMA to 0 here will ensure that relocs against these
12598 	 sections are handled correctly.  */
12599       if ((o->flags & SEC_ALLOC) == 0
12600 	  && ! o->user_set_vma)
12601 	o->vma = 0;
12602     }
12603 
12604   if (! bfd_link_relocatable (info) && merged)
12605     elf_link_hash_traverse (htab, _bfd_elf_link_sec_merge_syms, abfd);
12606 
12607   /* Figure out the file positions for everything but the symbol table
12608      and the relocs.  We set symcount to force assign_section_numbers
12609      to create a symbol table.  */
12610   abfd->symcount = info->strip != strip_all || emit_relocs;
12611   BFD_ASSERT (! abfd->output_has_begun);
12612   if (! _bfd_elf_compute_section_file_positions (abfd, info))
12613     goto error_return;
12614 
12615   /* Set sizes, and assign file positions for reloc sections.  */
12616   for (o = abfd->sections; o != NULL; o = o->next)
12617     {
12618       struct bfd_elf_section_data *esdo = elf_section_data (o);
12619       if ((o->flags & SEC_RELOC) != 0)
12620 	{
12621 	  if (esdo->rel.hdr
12622 	      && !(_bfd_elf_link_size_reloc_section (abfd, &esdo->rel)))
12623 	    goto error_return;
12624 
12625 	  if (esdo->rela.hdr
12626 	      && !(_bfd_elf_link_size_reloc_section (abfd, &esdo->rela)))
12627 	    goto error_return;
12628 	}
12629 
12630       /* _bfd_elf_compute_section_file_positions makes temporary use
12631 	 of target_index.  Reset it.  */
12632       o->target_index = 0;
12633 
12634       /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
12635 	 to count upwards while actually outputting the relocations.  */
12636       esdo->rel.count = 0;
12637       esdo->rela.count = 0;
12638 
12639       if ((esdo->this_hdr.sh_offset == (file_ptr) -1)
12640 	  && !bfd_section_is_ctf (o))
12641 	{
12642 	  /* Cache the section contents so that they can be compressed
12643 	     later.  Use bfd_malloc since it will be freed by
12644 	     bfd_compress_section_contents.  */
12645 	  unsigned char *contents = esdo->this_hdr.contents;
12646 	  if (contents != NULL)
12647 	    abort ();
12648 	  contents
12649 	    = (unsigned char *) bfd_malloc (esdo->this_hdr.sh_size);
12650 	  if (contents == NULL)
12651 	    goto error_return;
12652 	  esdo->this_hdr.contents = contents;
12653 	}
12654     }
12655 
12656   /* We have now assigned file positions for all the sections except .symtab,
12657      .strtab, and non-loaded reloc and compressed debugging sections.  We start
12658      the .symtab section at the current file position, and write directly to it.
12659      We build the .strtab section in memory.  */
12660   abfd->symcount = 0;
12661   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
12662   /* sh_name is set in prep_headers.  */
12663   symtab_hdr->sh_type = SHT_SYMTAB;
12664   /* sh_flags, sh_addr and sh_size all start off zero.  */
12665   symtab_hdr->sh_entsize = bed->s->sizeof_sym;
12666   /* sh_link is set in assign_section_numbers.  */
12667   /* sh_info is set below.  */
12668   /* sh_offset is set just below.  */
12669   symtab_hdr->sh_addralign = (bfd_vma) 1 << bed->s->log_file_align;
12670 
12671   if (max_sym_count < 20)
12672     max_sym_count = 20;
12673   htab->strtabsize = max_sym_count;
12674   amt = max_sym_count * sizeof (struct elf_sym_strtab);
12675   htab->strtab = (struct elf_sym_strtab *) bfd_malloc (amt);
12676   if (htab->strtab == NULL)
12677     goto error_return;
12678   /* The real buffer will be allocated in elf_link_swap_symbols_out.  */
12679   flinfo.symshndxbuf
12680     = (elf_numsections (abfd) > (SHN_LORESERVE & 0xFFFF)
12681        ? (Elf_External_Sym_Shndx *) -1 : NULL);
12682 
12683   if (info->strip != strip_all || emit_relocs)
12684     {
12685       file_ptr off = elf_next_file_pos (abfd);
12686 
12687       _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
12688 
12689       /* Note that at this point elf_next_file_pos (abfd) is
12690 	 incorrect.  We do not yet know the size of the .symtab section.
12691 	 We correct next_file_pos below, after we do know the size.  */
12692 
12693       /* Start writing out the symbol table.  The first symbol is always a
12694 	 dummy symbol.  */
12695       elfsym.st_value = 0;
12696       elfsym.st_size = 0;
12697       elfsym.st_info = 0;
12698       elfsym.st_other = 0;
12699       elfsym.st_shndx = SHN_UNDEF;
12700       elfsym.st_target_internal = 0;
12701       if (elf_link_output_symstrtab (&flinfo, NULL, &elfsym,
12702 				     bfd_und_section_ptr, NULL) != 1)
12703 	goto error_return;
12704 
12705       /* Output a symbol for each section if asked or they are used for
12706 	 relocs.  These symbols usually have no names.  We store the
12707 	 index of each one in the index field of the section, so that
12708 	 we can find it again when outputting relocs.  */
12709 
12710       if (bfd_keep_unused_section_symbols (abfd) || emit_relocs)
12711 	{
12712 	  bool name_local_sections
12713 	    = (bed->elf_backend_name_local_section_symbols
12714 	       && bed->elf_backend_name_local_section_symbols (abfd));
12715 	  const char *name = NULL;
12716 
12717 	  elfsym.st_size = 0;
12718 	  elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
12719 	  elfsym.st_other = 0;
12720 	  elfsym.st_value = 0;
12721 	  elfsym.st_target_internal = 0;
12722 	  for (i = 1; i < elf_numsections (abfd); i++)
12723 	    {
12724 	      o = bfd_section_from_elf_index (abfd, i);
12725 	      if (o != NULL)
12726 		{
12727 		  o->target_index = bfd_get_symcount (abfd);
12728 		  elfsym.st_shndx = i;
12729 		  if (!bfd_link_relocatable (info))
12730 		    elfsym.st_value = o->vma;
12731 		  if (name_local_sections)
12732 		    name = o->name;
12733 		  if (elf_link_output_symstrtab (&flinfo, name, &elfsym, o,
12734 						 NULL) != 1)
12735 		    goto error_return;
12736 		}
12737 	    }
12738 	}
12739     }
12740 
12741   /* On some targets like Irix 5 the symbol split between local and global
12742      ones recorded in the sh_info field needs to be done between section
12743      and all other symbols.  */
12744   if (bed->elf_backend_elfsym_local_is_section
12745       && bed->elf_backend_elfsym_local_is_section (abfd))
12746     symtab_hdr->sh_info = bfd_get_symcount (abfd);
12747 
12748   /* Allocate some memory to hold information read in from the input
12749      files.  */
12750   if (max_contents_size != 0)
12751     {
12752       flinfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
12753       if (flinfo.contents == NULL)
12754 	goto error_return;
12755     }
12756 
12757   if (max_external_reloc_size != 0)
12758     {
12759       flinfo.external_relocs = bfd_malloc (max_external_reloc_size);
12760       if (flinfo.external_relocs == NULL)
12761 	goto error_return;
12762     }
12763 
12764   if (max_internal_reloc_count != 0)
12765     {
12766       amt = max_internal_reloc_count * sizeof (Elf_Internal_Rela);
12767       flinfo.internal_relocs = (Elf_Internal_Rela *) bfd_malloc (amt);
12768       if (flinfo.internal_relocs == NULL)
12769 	goto error_return;
12770     }
12771 
12772   if (max_sym_count != 0)
12773     {
12774       amt = max_sym_count * bed->s->sizeof_sym;
12775       flinfo.external_syms = (bfd_byte *) bfd_malloc (amt);
12776       if (flinfo.external_syms == NULL)
12777 	goto error_return;
12778 
12779       amt = max_sym_count * sizeof (Elf_Internal_Sym);
12780       flinfo.internal_syms = (Elf_Internal_Sym *) bfd_malloc (amt);
12781       if (flinfo.internal_syms == NULL)
12782 	goto error_return;
12783 
12784       amt = max_sym_count * sizeof (long);
12785       flinfo.indices = (long int *) bfd_malloc (amt);
12786       if (flinfo.indices == NULL)
12787 	goto error_return;
12788 
12789       amt = max_sym_count * sizeof (asection *);
12790       flinfo.sections = (asection **) bfd_malloc (amt);
12791       if (flinfo.sections == NULL)
12792 	goto error_return;
12793     }
12794 
12795   if (max_sym_shndx_count != 0)
12796     {
12797       amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
12798       flinfo.locsym_shndx = (Elf_External_Sym_Shndx *) bfd_malloc (amt);
12799       if (flinfo.locsym_shndx == NULL)
12800 	goto error_return;
12801     }
12802 
12803   if (htab->tls_sec)
12804     {
12805       bfd_vma base, end = 0;  /* Both bytes.  */
12806       asection *sec;
12807 
12808       for (sec = htab->tls_sec;
12809 	   sec && (sec->flags & SEC_THREAD_LOCAL);
12810 	   sec = sec->next)
12811 	{
12812 	  bfd_size_type size = sec->size;
12813 	  unsigned int opb = bfd_octets_per_byte (abfd, sec);
12814 
12815 	  if (size == 0
12816 	      && (sec->flags & SEC_HAS_CONTENTS) == 0)
12817 	    {
12818 	      struct bfd_link_order *ord = sec->map_tail.link_order;
12819 
12820 	      if (ord != NULL)
12821 		size = ord->offset * opb + ord->size;
12822 	    }
12823 	  end = sec->vma + size / opb;
12824 	}
12825       base = htab->tls_sec->vma;
12826       /* Only align end of TLS section if static TLS doesn't have special
12827 	 alignment requirements.  */
12828       if (bed->static_tls_alignment == 1)
12829 	end = align_power (end, htab->tls_sec->alignment_power);
12830       htab->tls_size = end - base;
12831     }
12832 
12833   if (!_bfd_elf_fixup_eh_frame_hdr (info))
12834     return false;
12835 
12836   /* Finish relative relocations here after regular symbol processing
12837      is finished if DT_RELR is enabled.  */
12838   if (info->enable_dt_relr
12839       && bed->finish_relative_relocs
12840       && !bed->finish_relative_relocs (info))
12841     info->callbacks->einfo
12842       (_("%F%P: %pB: failed to finish relative relocations\n"), abfd);
12843 
12844   /* Since ELF permits relocations to be against local symbols, we
12845      must have the local symbols available when we do the relocations.
12846      Since we would rather only read the local symbols once, and we
12847      would rather not keep them in memory, we handle all the
12848      relocations for a single input file at the same time.
12849 
12850      Unfortunately, there is no way to know the total number of local
12851      symbols until we have seen all of them, and the local symbol
12852      indices precede the global symbol indices.  This means that when
12853      we are generating relocatable output, and we see a reloc against
12854      a global symbol, we can not know the symbol index until we have
12855      finished examining all the local symbols to see which ones we are
12856      going to output.  To deal with this, we keep the relocations in
12857      memory, and don't output them until the end of the link.  This is
12858      an unfortunate waste of memory, but I don't see a good way around
12859      it.  Fortunately, it only happens when performing a relocatable
12860      link, which is not the common case.  FIXME: If keep_memory is set
12861      we could write the relocs out and then read them again; I don't
12862      know how bad the memory loss will be.  */
12863 
12864   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
12865     sub->output_has_begun = false;
12866   for (o = abfd->sections; o != NULL; o = o->next)
12867     {
12868       for (p = o->map_head.link_order; p != NULL; p = p->next)
12869 	{
12870 	  if (p->type == bfd_indirect_link_order
12871 	      && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
12872 		  == bfd_target_elf_flavour)
12873 	      && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
12874 	    {
12875 	      if (! sub->output_has_begun)
12876 		{
12877 		  if (! elf_link_input_bfd (&flinfo, sub))
12878 		    goto error_return;
12879 		  sub->output_has_begun = true;
12880 		}
12881 	    }
12882 	  else if (p->type == bfd_section_reloc_link_order
12883 		   || p->type == bfd_symbol_reloc_link_order)
12884 	    {
12885 	      if (! elf_reloc_link_order (abfd, info, o, p))
12886 		goto error_return;
12887 	    }
12888 	  else
12889 	    {
12890 	      if (! _bfd_default_link_order (abfd, info, o, p))
12891 		{
12892 		  if (p->type == bfd_indirect_link_order
12893 		      && (bfd_get_flavour (sub)
12894 			  == bfd_target_elf_flavour)
12895 		      && (elf_elfheader (sub)->e_ident[EI_CLASS]
12896 			  != bed->s->elfclass))
12897 		    {
12898 		      const char *iclass, *oclass;
12899 
12900 		      switch (bed->s->elfclass)
12901 			{
12902 			case ELFCLASS64: oclass = "ELFCLASS64"; break;
12903 			case ELFCLASS32: oclass = "ELFCLASS32"; break;
12904 			case ELFCLASSNONE: oclass = "ELFCLASSNONE"; break;
12905 			default: abort ();
12906 			}
12907 
12908 		      switch (elf_elfheader (sub)->e_ident[EI_CLASS])
12909 			{
12910 			case ELFCLASS64: iclass = "ELFCLASS64"; break;
12911 			case ELFCLASS32: iclass = "ELFCLASS32"; break;
12912 			case ELFCLASSNONE: iclass = "ELFCLASSNONE"; break;
12913 			default: abort ();
12914 			}
12915 
12916 		      bfd_set_error (bfd_error_wrong_format);
12917 		      _bfd_error_handler
12918 			/* xgettext:c-format */
12919 			(_("%pB: file class %s incompatible with %s"),
12920 			 sub, iclass, oclass);
12921 		    }
12922 
12923 		  goto error_return;
12924 		}
12925 	    }
12926 	}
12927     }
12928 
12929   /* Free symbol buffer if needed.  */
12930   if (!info->reduce_memory_overheads)
12931     {
12932       for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
12933 	if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
12934 	  {
12935 	    free (elf_tdata (sub)->symbuf);
12936 	    elf_tdata (sub)->symbuf = NULL;
12937 	  }
12938     }
12939 
12940   ret = true;
12941 
12942   /* Output any global symbols that got converted to local in a
12943      version script or due to symbol visibility.  We do this in a
12944      separate step since ELF requires all local symbols to appear
12945      prior to any global symbols.  FIXME: We should only do this if
12946      some global symbols were, in fact, converted to become local.
12947      FIXME: Will this work correctly with the Irix 5 linker?  */
12948   eoinfo.failed = false;
12949   eoinfo.flinfo = &flinfo;
12950   eoinfo.localsyms = true;
12951   eoinfo.file_sym_done = false;
12952   bfd_hash_traverse (&info->hash->table, elf_link_output_extsym, &eoinfo);
12953   if (eoinfo.failed)
12954     {
12955       ret = false;
12956       goto return_local_hash_table;
12957     }
12958 
12959   /* If backend needs to output some local symbols not present in the hash
12960      table, do it now.  */
12961   if (bed->elf_backend_output_arch_local_syms)
12962     {
12963       if (! ((*bed->elf_backend_output_arch_local_syms)
12964 	     (abfd, info, &flinfo, elf_link_output_symstrtab)))
12965 	{
12966 	  ret = false;
12967 	  goto return_local_hash_table;
12968 	}
12969     }
12970 
12971   /* That wrote out all the local symbols.  Finish up the symbol table
12972      with the global symbols. Even if we want to strip everything we
12973      can, we still need to deal with those global symbols that got
12974      converted to local in a version script.  */
12975 
12976   /* The sh_info field records the index of the first non local symbol.  */
12977   if (!symtab_hdr->sh_info)
12978     symtab_hdr->sh_info = bfd_get_symcount (abfd);
12979 
12980   if (dynamic
12981       && htab->dynsym != NULL
12982       && htab->dynsym->output_section != bfd_abs_section_ptr)
12983     {
12984       Elf_Internal_Sym sym;
12985       bfd_byte *dynsym = htab->dynsym->contents;
12986 
12987       o = htab->dynsym->output_section;
12988       elf_section_data (o)->this_hdr.sh_info = htab->local_dynsymcount + 1;
12989 
12990       /* Write out the section symbols for the output sections.  */
12991       if (bfd_link_pic (info)
12992 	  || htab->is_relocatable_executable)
12993 	{
12994 	  asection *s;
12995 
12996 	  sym.st_size = 0;
12997 	  sym.st_name = 0;
12998 	  sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
12999 	  sym.st_other = 0;
13000 	  sym.st_target_internal = 0;
13001 
13002 	  for (s = abfd->sections; s != NULL; s = s->next)
13003 	    {
13004 	      int indx;
13005 	      bfd_byte *dest;
13006 	      long dynindx;
13007 
13008 	      dynindx = elf_section_data (s)->dynindx;
13009 	      if (dynindx <= 0)
13010 		continue;
13011 	      indx = elf_section_data (s)->this_idx;
13012 	      BFD_ASSERT (indx > 0);
13013 	      sym.st_shndx = indx;
13014 	      if (! check_dynsym (abfd, &sym))
13015 		{
13016 		  ret = false;
13017 		  goto return_local_hash_table;
13018 		}
13019 	      sym.st_value = s->vma;
13020 	      dest = dynsym + dynindx * bed->s->sizeof_sym;
13021 
13022 	      /* Inform the linker of the addition of this symbol.  */
13023 
13024 	      if (info->callbacks->ctf_new_dynsym)
13025 		info->callbacks->ctf_new_dynsym (dynindx, &sym);
13026 
13027 	      bed->s->swap_symbol_out (abfd, &sym, dest, 0);
13028 	    }
13029 	}
13030 
13031       /* Write out the local dynsyms.  */
13032       if (htab->dynlocal)
13033 	{
13034 	  struct elf_link_local_dynamic_entry *e;
13035 	  for (e = htab->dynlocal; e ; e = e->next)
13036 	    {
13037 	      asection *s;
13038 	      bfd_byte *dest;
13039 
13040 	      /* Copy the internal symbol and turn off visibility.
13041 		 Note that we saved a word of storage and overwrote
13042 		 the original st_name with the dynstr_index.  */
13043 	      sym = e->isym;
13044 	      sym.st_other &= ~ELF_ST_VISIBILITY (-1);
13045 	      sym.st_shndx = SHN_UNDEF;
13046 
13047 	      s = bfd_section_from_elf_index (e->input_bfd,
13048 					      e->isym.st_shndx);
13049 	      if (s != NULL
13050 		  && s->output_section != NULL
13051 		  && elf_section_data (s->output_section) != NULL)
13052 		{
13053 		  sym.st_shndx =
13054 		    elf_section_data (s->output_section)->this_idx;
13055 		  if (! check_dynsym (abfd, &sym))
13056 		    {
13057 		      ret = false;
13058 		      goto return_local_hash_table;
13059 		    }
13060 		  sym.st_value = (s->output_section->vma
13061 				  + s->output_offset
13062 				  + e->isym.st_value);
13063 		}
13064 
13065 	      /* Inform the linker of the addition of this symbol.  */
13066 
13067 	      if (info->callbacks->ctf_new_dynsym)
13068 		info->callbacks->ctf_new_dynsym (e->dynindx, &sym);
13069 
13070 	      dest = dynsym + e->dynindx * bed->s->sizeof_sym;
13071 	      bed->s->swap_symbol_out (abfd, &sym, dest, 0);
13072 	    }
13073 	}
13074     }
13075 
13076   /* We get the global symbols from the hash table.  */
13077   eoinfo.failed = false;
13078   eoinfo.localsyms = false;
13079   eoinfo.flinfo = &flinfo;
13080   bfd_hash_traverse (&info->hash->table, elf_link_output_extsym, &eoinfo);
13081   if (eoinfo.failed)
13082     {
13083       ret = false;
13084       goto return_local_hash_table;
13085     }
13086 
13087   /* If backend needs to output some symbols not present in the hash
13088      table, do it now.  */
13089   if (bed->elf_backend_output_arch_syms
13090       && (info->strip != strip_all || emit_relocs))
13091     {
13092       if (! ((*bed->elf_backend_output_arch_syms)
13093 	     (abfd, info, &flinfo, elf_link_output_symstrtab)))
13094 	{
13095 	  ret = false;
13096 	  goto return_local_hash_table;
13097 	}
13098     }
13099 
13100   /* Finalize the .strtab section.  */
13101   _bfd_elf_strtab_finalize (flinfo.symstrtab);
13102 
13103   /* Swap out the .strtab section. */
13104   if (!elf_link_swap_symbols_out (&flinfo))
13105     {
13106       ret = false;
13107       goto return_local_hash_table;
13108     }
13109 
13110   /* Now we know the size of the symtab section.  */
13111   if (bfd_get_symcount (abfd) > 0)
13112     {
13113       /* Finish up and write out the symbol string table (.strtab)
13114 	 section.  */
13115       Elf_Internal_Shdr *symstrtab_hdr = NULL;
13116       file_ptr off = symtab_hdr->sh_offset + symtab_hdr->sh_size;
13117 
13118       if (elf_symtab_shndx_list (abfd))
13119 	{
13120 	  symtab_shndx_hdr = & elf_symtab_shndx_list (abfd)->hdr;
13121 
13122 	  if (symtab_shndx_hdr != NULL && symtab_shndx_hdr->sh_name != 0)
13123 	    {
13124 	      symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
13125 	      symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
13126 	      symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
13127 	      amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
13128 	      symtab_shndx_hdr->sh_size = amt;
13129 
13130 	      off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
13131 							       off, true);
13132 
13133 	      if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
13134 		  || (bfd_write (flinfo.symshndxbuf, amt, abfd) != amt))
13135 		{
13136 		  ret = false;
13137 		  goto return_local_hash_table;
13138 		}
13139 	    }
13140 	}
13141 
13142       symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
13143       /* sh_name was set in prep_headers.  */
13144       symstrtab_hdr->sh_type = SHT_STRTAB;
13145       symstrtab_hdr->sh_flags = bed->elf_strtab_flags;
13146       symstrtab_hdr->sh_addr = 0;
13147       symstrtab_hdr->sh_size = _bfd_elf_strtab_size (flinfo.symstrtab);
13148       symstrtab_hdr->sh_entsize = 0;
13149       symstrtab_hdr->sh_link = 0;
13150       symstrtab_hdr->sh_info = 0;
13151       /* sh_offset is set just below.  */
13152       symstrtab_hdr->sh_addralign = 1;
13153 
13154       off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr,
13155 						       off, true);
13156       elf_next_file_pos (abfd) = off;
13157 
13158       if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
13159 	  || ! _bfd_elf_strtab_emit (abfd, flinfo.symstrtab))
13160 	{
13161 	  ret = false;
13162 	  goto return_local_hash_table;
13163 	}
13164     }
13165 
13166   if (info->out_implib_bfd && !elf_output_implib (abfd, info))
13167     {
13168       _bfd_error_handler (_("%pB: failed to generate import library"),
13169 			  info->out_implib_bfd);
13170       ret = false;
13171       goto return_local_hash_table;
13172     }
13173 
13174   /* Adjust the relocs to have the correct symbol indices.  */
13175   for (o = abfd->sections; o != NULL; o = o->next)
13176     {
13177       struct bfd_elf_section_data *esdo = elf_section_data (o);
13178       bool sort;
13179 
13180       if ((o->flags & SEC_RELOC) == 0)
13181 	continue;
13182 
13183       sort = bed->sort_relocs_p == NULL || (*bed->sort_relocs_p) (o);
13184       if (esdo->rel.hdr != NULL
13185 	  && !elf_link_adjust_relocs (abfd, o, &esdo->rel, sort, info))
13186 	{
13187 	  ret = false;
13188 	  goto return_local_hash_table;
13189 	}
13190       if (esdo->rela.hdr != NULL
13191 	  && !elf_link_adjust_relocs (abfd, o, &esdo->rela, sort, info))
13192 	{
13193 	  ret = false;
13194 	  goto return_local_hash_table;
13195 	}
13196 
13197       /* Set the reloc_count field to 0 to prevent write_relocs from
13198 	 trying to swap the relocs out itself.  */
13199       o->reloc_count = 0;
13200     }
13201 
13202   relativecount = 0;
13203   if (dynamic && info->combreloc && dynobj != NULL)
13204     relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
13205 
13206   relr_entsize = 0;
13207   if (htab->srelrdyn != NULL
13208       && htab->srelrdyn->output_section != NULL
13209       && htab->srelrdyn->size != 0)
13210     {
13211       asection *s = htab->srelrdyn->output_section;
13212       relr_entsize = elf_section_data (s)->this_hdr.sh_entsize;
13213       if (relr_entsize == 0)
13214 	{
13215 	  relr_entsize = bed->s->arch_size / 8;
13216 	  elf_section_data (s)->this_hdr.sh_entsize = relr_entsize;
13217 	}
13218     }
13219 
13220   /* If we are linking against a dynamic object, or generating a
13221      shared library, finish up the dynamic linking information.  */
13222   if (dynamic)
13223     {
13224       bfd_byte *dyncon, *dynconend;
13225 
13226       /* Fix up .dynamic entries.  */
13227       o = bfd_get_linker_section (dynobj, ".dynamic");
13228       BFD_ASSERT (o != NULL);
13229 
13230       dyncon = o->contents;
13231       dynconend = PTR_ADD (o->contents, o->size);
13232       for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
13233 	{
13234 	  Elf_Internal_Dyn dyn;
13235 	  const char *name;
13236 	  unsigned int type;
13237 	  bfd_size_type sh_size;
13238 	  bfd_vma sh_addr;
13239 
13240 	  bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
13241 
13242 	  switch (dyn.d_tag)
13243 	    {
13244 	    default:
13245 	      continue;
13246 	    case DT_NULL:
13247 	      if (relativecount != 0)
13248 		{
13249 		  switch (elf_section_data (reldyn)->this_hdr.sh_type)
13250 		    {
13251 		    case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
13252 		    case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
13253 		    }
13254 		  if (dyn.d_tag != DT_NULL
13255 		      && dynconend - dyncon >= bed->s->sizeof_dyn)
13256 		    {
13257 		      dyn.d_un.d_val = relativecount;
13258 		      relativecount = 0;
13259 		      break;
13260 		    }
13261 		  relativecount = 0;
13262 		}
13263 	      if (relr_entsize != 0)
13264 		{
13265 		  if (dynconend - dyncon >= 3 * bed->s->sizeof_dyn)
13266 		    {
13267 		      asection *s = htab->srelrdyn;
13268 		      dyn.d_tag = DT_RELR;
13269 		      dyn.d_un.d_ptr
13270 			= s->output_section->vma + s->output_offset;
13271 		      bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
13272 		      dyncon += bed->s->sizeof_dyn;
13273 
13274 		      dyn.d_tag = DT_RELRSZ;
13275 		      dyn.d_un.d_val = s->size;
13276 		      bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
13277 		      dyncon += bed->s->sizeof_dyn;
13278 
13279 		      dyn.d_tag = DT_RELRENT;
13280 		      dyn.d_un.d_val = relr_entsize;
13281 		      relr_entsize = 0;
13282 		      break;
13283 		    }
13284 		  relr_entsize = 0;
13285 		}
13286 	      continue;
13287 
13288 	    case DT_INIT:
13289 	      name = info->init_function;
13290 	      goto get_sym;
13291 	    case DT_FINI:
13292 	      name = info->fini_function;
13293 	    get_sym:
13294 	      {
13295 		struct elf_link_hash_entry *h;
13296 
13297 		h = elf_link_hash_lookup (htab, name, false, false, true);
13298 		if (h != NULL
13299 		    && (h->root.type == bfd_link_hash_defined
13300 			|| h->root.type == bfd_link_hash_defweak))
13301 		  {
13302 		    dyn.d_un.d_ptr = h->root.u.def.value;
13303 		    o = h->root.u.def.section;
13304 		    if (o->output_section != NULL)
13305 		      dyn.d_un.d_ptr += (o->output_section->vma
13306 					 + o->output_offset);
13307 		    else
13308 		      {
13309 			/* The symbol is imported from another shared
13310 			   library and does not apply to this one.  */
13311 			dyn.d_un.d_ptr = 0;
13312 		      }
13313 		    break;
13314 		  }
13315 	      }
13316 	      continue;
13317 
13318 	    case DT_PREINIT_ARRAYSZ:
13319 	      name = ".preinit_array";
13320 	      goto get_out_size;
13321 	    case DT_INIT_ARRAYSZ:
13322 	      name = ".init_array";
13323 	      goto get_out_size;
13324 	    case DT_FINI_ARRAYSZ:
13325 	      name = ".fini_array";
13326 	    get_out_size:
13327 	      o = bfd_get_section_by_name (abfd, name);
13328 	      if (o == NULL)
13329 		{
13330 		  _bfd_error_handler
13331 		    (_("could not find section %s"), name);
13332 		  goto error_return;
13333 		}
13334 	      if (o->size == 0)
13335 		_bfd_error_handler
13336 		  (_("warning: %s section has zero size"), name);
13337 	      dyn.d_un.d_val = o->size;
13338 	      break;
13339 
13340 	    case DT_PREINIT_ARRAY:
13341 	      name = ".preinit_array";
13342 	      goto get_out_vma;
13343 	    case DT_INIT_ARRAY:
13344 	      name = ".init_array";
13345 	      goto get_out_vma;
13346 	    case DT_FINI_ARRAY:
13347 	      name = ".fini_array";
13348 	    get_out_vma:
13349 	      o = bfd_get_section_by_name (abfd, name);
13350 	      goto do_vma;
13351 
13352 	    case DT_HASH:
13353 	      name = ".hash";
13354 	      goto get_vma;
13355 	    case DT_GNU_HASH:
13356 	      name = ".gnu.hash";
13357 	      goto get_vma;
13358 	    case DT_STRTAB:
13359 	      name = ".dynstr";
13360 	      goto get_vma;
13361 	    case DT_SYMTAB:
13362 	      name = ".dynsym";
13363 	      goto get_vma;
13364 	    case DT_VERDEF:
13365 	      name = ".gnu.version_d";
13366 	      goto get_vma;
13367 	    case DT_VERNEED:
13368 	      name = ".gnu.version_r";
13369 	      goto get_vma;
13370 	    case DT_VERSYM:
13371 	      name = ".gnu.version";
13372 	    get_vma:
13373 	      o = bfd_get_linker_section (dynobj, name);
13374 	    do_vma:
13375 	      if (o == NULL || bfd_is_abs_section (o->output_section))
13376 		{
13377 		  _bfd_error_handler
13378 		    (_("could not find section %s"), name);
13379 		  goto error_return;
13380 		}
13381 	      if (elf_section_data (o->output_section)->this_hdr.sh_type == SHT_NOTE)
13382 		{
13383 		  _bfd_error_handler
13384 		    (_("warning: section '%s' is being made into a note"), name);
13385 		  bfd_set_error (bfd_error_nonrepresentable_section);
13386 		  goto error_return;
13387 		}
13388 	      dyn.d_un.d_ptr = o->output_section->vma + o->output_offset;
13389 	      break;
13390 
13391 	    case DT_REL:
13392 	    case DT_RELA:
13393 	    case DT_RELSZ:
13394 	    case DT_RELASZ:
13395 	      if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
13396 		type = SHT_REL;
13397 	      else
13398 		type = SHT_RELA;
13399 	      sh_size = 0;
13400 	      sh_addr = 0;
13401 	      for (i = 1; i < elf_numsections (abfd); i++)
13402 		{
13403 		  Elf_Internal_Shdr *hdr;
13404 
13405 		  hdr = elf_elfsections (abfd)[i];
13406 		  if (hdr->sh_type == type
13407 		      && (hdr->sh_flags & SHF_ALLOC) != 0)
13408 		    {
13409 		      sh_size += hdr->sh_size;
13410 		      if (sh_addr == 0
13411 			  || sh_addr > hdr->sh_addr)
13412 			sh_addr = hdr->sh_addr;
13413 		    }
13414 		}
13415 
13416 	      if (bed->dtrel_excludes_plt && htab->srelplt != NULL)
13417 		{
13418 		  unsigned int opb = bfd_octets_per_byte (abfd, o);
13419 
13420 		  /* Don't count procedure linkage table relocs in the
13421 		     overall reloc count.  */
13422 		  sh_size -= htab->srelplt->size;
13423 		  if (sh_size == 0)
13424 		    /* If the size is zero, make the address zero too.
13425 		       This is to avoid a glibc bug.  If the backend
13426 		       emits DT_RELA/DT_RELASZ even when DT_RELASZ is
13427 		       zero, then we'll put DT_RELA at the end of
13428 		       DT_JMPREL.  glibc will interpret the end of
13429 		       DT_RELA matching the end of DT_JMPREL as the
13430 		       case where DT_RELA includes DT_JMPREL, and for
13431 		       LD_BIND_NOW will decide that processing DT_RELA
13432 		       will process the PLT relocs too.  Net result:
13433 		       No PLT relocs applied.  */
13434 		    sh_addr = 0;
13435 
13436 		  /* If .rela.plt is the first .rela section, exclude
13437 		     it from DT_RELA.  */
13438 		  else if (sh_addr == (htab->srelplt->output_section->vma
13439 				       + htab->srelplt->output_offset) * opb)
13440 		    sh_addr += htab->srelplt->size;
13441 		}
13442 
13443 	      if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
13444 		dyn.d_un.d_val = sh_size;
13445 	      else
13446 		dyn.d_un.d_ptr = sh_addr;
13447 	      break;
13448 	    }
13449 	  bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
13450 	}
13451     }
13452 
13453   /* If we have created any dynamic sections, then output them.  */
13454   if (dynobj != NULL)
13455     {
13456       if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
13457 	goto error_return;
13458 
13459       /* Check for DT_TEXTREL (late, in case the backend removes it).  */
13460       if (bfd_link_textrel_check (info)
13461 	  && (o = bfd_get_linker_section (dynobj, ".dynamic")) != NULL
13462 	  && o->size != 0)
13463 	{
13464 	  bfd_byte *dyncon, *dynconend;
13465 
13466 	  dyncon = o->contents;
13467 	  dynconend = o->contents + o->size;
13468 	  for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
13469 	    {
13470 	      Elf_Internal_Dyn dyn;
13471 
13472 	      bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
13473 
13474 	      if (dyn.d_tag == DT_TEXTREL)
13475 		{
13476 		  if (info->textrel_check == textrel_check_error)
13477 		    info->callbacks->einfo
13478 		      (_("%P%X: read-only segment has dynamic relocations\n"));
13479 		  else if (bfd_link_dll (info))
13480 		    info->callbacks->einfo
13481 		      (_("%P: warning: creating DT_TEXTREL in a shared object\n"));
13482 		  else if (bfd_link_pde (info))
13483 		    info->callbacks->einfo
13484 		      (_("%P: warning: creating DT_TEXTREL in a PDE\n"));
13485 		  else
13486 		    info->callbacks->einfo
13487 		      (_("%P: warning: creating DT_TEXTREL in a PIE\n"));
13488 		  break;
13489 		}
13490 	    }
13491 	}
13492 
13493       for (o = dynobj->sections; o != NULL; o = o->next)
13494 	{
13495 	  if ((o->flags & SEC_HAS_CONTENTS) == 0
13496 	      || o->size == 0
13497 	      || o->output_section == bfd_abs_section_ptr)
13498 	    continue;
13499 	  if ((o->flags & SEC_LINKER_CREATED) == 0)
13500 	    {
13501 	      /* At this point, we are only interested in sections
13502 		 created by _bfd_elf_link_create_dynamic_sections.  */
13503 	      continue;
13504 	    }
13505 	  if (htab->stab_info.stabstr == o)
13506 	    continue;
13507 	  if (htab->eh_info.hdr_sec == o)
13508 	    continue;
13509 	  if (strcmp (o->name, ".dynstr") != 0)
13510 	    {
13511 	      bfd_size_type octets = ((file_ptr) o->output_offset
13512 				      * bfd_octets_per_byte (abfd, o));
13513 	      if (!bfd_set_section_contents (abfd, o->output_section,
13514 					     o->contents, octets, o->size))
13515 		goto error_return;
13516 	    }
13517 	  else
13518 	    {
13519 	      /* The contents of the .dynstr section are actually in a
13520 		 stringtab.  */
13521 	      file_ptr off;
13522 
13523 	      off = elf_section_data (o->output_section)->this_hdr.sh_offset;
13524 	      if (bfd_seek (abfd, off, SEEK_SET) != 0
13525 		  || !_bfd_elf_strtab_emit (abfd, htab->dynstr))
13526 		goto error_return;
13527 	    }
13528 	}
13529     }
13530 
13531   if (!info->resolve_section_groups)
13532     {
13533       bool failed = false;
13534 
13535       BFD_ASSERT (bfd_link_relocatable (info));
13536       bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
13537       if (failed)
13538 	goto error_return;
13539     }
13540 
13541   /* If we have optimized stabs strings, output them.  */
13542   if (htab->stab_info.stabstr != NULL)
13543     {
13544       if (!_bfd_write_stab_strings (abfd, &htab->stab_info))
13545 	goto error_return;
13546     }
13547 
13548   if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
13549     goto error_return;
13550 
13551   if (! _bfd_elf_write_section_sframe (abfd, info))
13552     goto error_return;
13553 
13554   if (info->callbacks->emit_ctf)
13555       info->callbacks->emit_ctf ();
13556 
13557   elf_final_link_free (abfd, &flinfo);
13558 
13559   if (attr_section)
13560     {
13561       bfd_byte *contents = (bfd_byte *) bfd_malloc (attr_size);
13562       if (contents == NULL)
13563 	{
13564 	  /* Bail out and fail.  */
13565 	  ret = false;
13566 	  goto return_local_hash_table;
13567 	}
13568       bfd_elf_set_obj_attr_contents (abfd, contents, attr_size);
13569       bfd_set_section_contents (abfd, attr_section, contents, 0, attr_size);
13570       free (contents);
13571     }
13572 
13573  return_local_hash_table:
13574   if (info->unique_symbol)
13575     bfd_hash_table_free (&flinfo.local_hash_table);
13576   return ret;
13577 
13578  error_return:
13579   elf_final_link_free (abfd, &flinfo);
13580   ret = false;
13581   goto return_local_hash_table;
13582 }
13583 
13584 /* Initialize COOKIE for input bfd ABFD.  */
13585 
13586 static bool
init_reloc_cookie(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,bfd * abfd)13587 init_reloc_cookie (struct elf_reloc_cookie *cookie,
13588 		   struct bfd_link_info *info, bfd *abfd)
13589 {
13590   Elf_Internal_Shdr *symtab_hdr;
13591   const struct elf_backend_data *bed;
13592 
13593   bed = get_elf_backend_data (abfd);
13594   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
13595 
13596   cookie->abfd = abfd;
13597   cookie->sym_hashes = elf_sym_hashes (abfd);
13598   cookie->bad_symtab = elf_bad_symtab (abfd);
13599   if (cookie->bad_symtab)
13600     {
13601       cookie->locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
13602       cookie->extsymoff = 0;
13603     }
13604   else
13605     {
13606       cookie->locsymcount = symtab_hdr->sh_info;
13607       cookie->extsymoff = symtab_hdr->sh_info;
13608     }
13609 
13610   if (bed->s->arch_size == 32)
13611     cookie->r_sym_shift = 8;
13612   else
13613     cookie->r_sym_shift = 32;
13614 
13615   cookie->locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
13616   if (cookie->locsyms == NULL && cookie->locsymcount != 0)
13617     {
13618       cookie->locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
13619 					      cookie->locsymcount, 0,
13620 					      NULL, NULL, NULL);
13621       if (cookie->locsyms == NULL)
13622 	{
13623 	  info->callbacks->einfo (_("%P%X: can not read symbols: %E\n"));
13624 	  return false;
13625 	}
13626       if (_bfd_link_keep_memory (info) )
13627 	{
13628 	  symtab_hdr->contents = (bfd_byte *) cookie->locsyms;
13629 	  info->cache_size += (cookie->locsymcount
13630 			       * sizeof (Elf_External_Sym_Shndx));
13631 	}
13632     }
13633   return true;
13634 }
13635 
13636 /* Free the memory allocated by init_reloc_cookie, if appropriate.  */
13637 
13638 static void
fini_reloc_cookie(struct elf_reloc_cookie * cookie,bfd * abfd)13639 fini_reloc_cookie (struct elf_reloc_cookie *cookie, bfd *abfd)
13640 {
13641   Elf_Internal_Shdr *symtab_hdr;
13642 
13643   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
13644   if (symtab_hdr->contents != (unsigned char *) cookie->locsyms)
13645     free (cookie->locsyms);
13646 }
13647 
13648 /* Initialize the relocation information in COOKIE for input section SEC
13649    of input bfd ABFD.  */
13650 
13651 static bool
init_reloc_cookie_rels(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,bfd * abfd,asection * sec)13652 init_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
13653 			struct bfd_link_info *info, bfd *abfd,
13654 			asection *sec)
13655 {
13656   if (sec->reloc_count == 0)
13657     {
13658       cookie->rels = NULL;
13659       cookie->relend = NULL;
13660     }
13661   else
13662     {
13663       cookie->rels = _bfd_elf_link_info_read_relocs (abfd, info, sec,
13664 						     NULL, NULL,
13665 						     _bfd_link_keep_memory (info));
13666       if (cookie->rels == NULL)
13667 	return false;
13668       cookie->rel = cookie->rels;
13669       cookie->relend = cookie->rels + sec->reloc_count;
13670     }
13671   cookie->rel = cookie->rels;
13672   return true;
13673 }
13674 
13675 /* Free the memory allocated by init_reloc_cookie_rels,
13676    if appropriate.  */
13677 
13678 static void
fini_reloc_cookie_rels(struct elf_reloc_cookie * cookie,asection * sec)13679 fini_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
13680 			asection *sec)
13681 {
13682   if (elf_section_data (sec)->relocs != cookie->rels)
13683     free (cookie->rels);
13684 }
13685 
13686 /* Initialize the whole of COOKIE for input section SEC.  */
13687 
13688 static bool
init_reloc_cookie_for_section(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,asection * sec)13689 init_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
13690 			       struct bfd_link_info *info,
13691 			       asection *sec)
13692 {
13693   if (!init_reloc_cookie (cookie, info, sec->owner))
13694     goto error1;
13695   if (!init_reloc_cookie_rels (cookie, info, sec->owner, sec))
13696     goto error2;
13697   return true;
13698 
13699  error2:
13700   fini_reloc_cookie (cookie, sec->owner);
13701  error1:
13702   return false;
13703 }
13704 
13705 /* Free the memory allocated by init_reloc_cookie_for_section,
13706    if appropriate.  */
13707 
13708 static void
fini_reloc_cookie_for_section(struct elf_reloc_cookie * cookie,asection * sec)13709 fini_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
13710 			       asection *sec)
13711 {
13712   fini_reloc_cookie_rels (cookie, sec);
13713   fini_reloc_cookie (cookie, sec->owner);
13714 }
13715 
13716 /* Garbage collect unused sections.  */
13717 
13718 /* Default gc_mark_hook.  */
13719 
13720 asection *
_bfd_elf_gc_mark_hook(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)13721 _bfd_elf_gc_mark_hook (asection *sec,
13722 		       struct bfd_link_info *info ATTRIBUTE_UNUSED,
13723 		       Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
13724 		       struct elf_link_hash_entry *h,
13725 		       Elf_Internal_Sym *sym)
13726 {
13727   if (h != NULL)
13728     {
13729       switch (h->root.type)
13730 	{
13731 	case bfd_link_hash_defined:
13732 	case bfd_link_hash_defweak:
13733 	  return h->root.u.def.section;
13734 
13735 	case bfd_link_hash_common:
13736 	  return h->root.u.c.p->section;
13737 
13738 	default:
13739 	  break;
13740 	}
13741     }
13742   else
13743     return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
13744 
13745   return NULL;
13746 }
13747 
13748 /* Return the debug definition section.  */
13749 
13750 static asection *
elf_gc_mark_debug_section(asection * sec ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)13751 elf_gc_mark_debug_section (asection *sec ATTRIBUTE_UNUSED,
13752 			   struct bfd_link_info *info ATTRIBUTE_UNUSED,
13753 			   Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
13754 			   struct elf_link_hash_entry *h,
13755 			   Elf_Internal_Sym *sym)
13756 {
13757   if (h != NULL)
13758     {
13759       /* Return the global debug definition section.  */
13760       if ((h->root.type == bfd_link_hash_defined
13761 	   || h->root.type == bfd_link_hash_defweak)
13762 	  && (h->root.u.def.section->flags & SEC_DEBUGGING) != 0)
13763 	return h->root.u.def.section;
13764     }
13765   else
13766     {
13767       /* Return the local debug definition section.  */
13768       asection *isec = bfd_section_from_elf_index (sec->owner,
13769 						   sym->st_shndx);
13770       if (isec != NULL && (isec->flags & SEC_DEBUGGING) != 0)
13771 	return isec;
13772     }
13773 
13774   return NULL;
13775 }
13776 
13777 /* COOKIE->rel describes a relocation against section SEC, which is
13778    a section we've decided to keep.  Return the section that contains
13779    the relocation symbol, or NULL if no section contains it.  */
13780 
13781 asection *
_bfd_elf_gc_mark_rsec(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook,struct elf_reloc_cookie * cookie,bool * start_stop)13782 _bfd_elf_gc_mark_rsec (struct bfd_link_info *info, asection *sec,
13783 		       elf_gc_mark_hook_fn gc_mark_hook,
13784 		       struct elf_reloc_cookie *cookie,
13785 		       bool *start_stop)
13786 {
13787   unsigned long r_symndx;
13788   struct elf_link_hash_entry *h, *hw;
13789 
13790   r_symndx = cookie->rel->r_info >> cookie->r_sym_shift;
13791   if (r_symndx == STN_UNDEF)
13792     return NULL;
13793 
13794   if (r_symndx >= cookie->locsymcount
13795       || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
13796     {
13797       bool was_marked;
13798 
13799       h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
13800       if (h == NULL)
13801 	{
13802 	  info->callbacks->einfo (_("%F%P: corrupt input: %pB\n"),
13803 				  sec->owner);
13804 	  return NULL;
13805 	}
13806       while (h->root.type == bfd_link_hash_indirect
13807 	     || h->root.type == bfd_link_hash_warning)
13808 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
13809 
13810       was_marked = h->mark;
13811       h->mark = 1;
13812       /* Keep all aliases of the symbol too.  If an object symbol
13813 	 needs to be copied into .dynbss then all of its aliases
13814 	 should be present as dynamic symbols, not just the one used
13815 	 on the copy relocation.  */
13816       hw = h;
13817       while (hw->is_weakalias)
13818 	{
13819 	  hw = hw->u.alias;
13820 	  hw->mark = 1;
13821 	}
13822 
13823       if (!was_marked && h->start_stop && !h->root.ldscript_def)
13824 	{
13825 	  if (info->start_stop_gc)
13826 	    return NULL;
13827 
13828 	  /* To work around a glibc bug, mark XXX input sections
13829 	     when there is a reference to __start_XXX or __stop_XXX
13830 	     symbols.  */
13831 	  else if (start_stop != NULL)
13832 	    {
13833 	      asection *s = h->u2.start_stop_section;
13834 	      *start_stop = true;
13835 	      return s;
13836 	    }
13837 	}
13838 
13839       return (*gc_mark_hook) (sec, info, cookie->rel, h, NULL);
13840     }
13841 
13842   return (*gc_mark_hook) (sec, info, cookie->rel, NULL,
13843 			  &cookie->locsyms[r_symndx]);
13844 }
13845 
13846 /* COOKIE->rel describes a relocation against section SEC, which is
13847    a section we've decided to keep.  Mark the section that contains
13848    the relocation symbol.  */
13849 
13850 bool
_bfd_elf_gc_mark_reloc(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook,struct elf_reloc_cookie * cookie)13851 _bfd_elf_gc_mark_reloc (struct bfd_link_info *info,
13852 			asection *sec,
13853 			elf_gc_mark_hook_fn gc_mark_hook,
13854 			struct elf_reloc_cookie *cookie)
13855 {
13856   asection *rsec;
13857   bool start_stop = false;
13858 
13859   rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie, &start_stop);
13860   while (rsec != NULL)
13861     {
13862       if (!rsec->gc_mark)
13863 	{
13864 	  if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour
13865 	      || (rsec->owner->flags & DYNAMIC) != 0)
13866 	    rsec->gc_mark = 1;
13867 	  else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
13868 	    return false;
13869 	}
13870       if (!start_stop)
13871 	break;
13872       rsec = bfd_get_next_section_by_name (rsec->owner, rsec);
13873     }
13874   return true;
13875 }
13876 
13877 /* The mark phase of garbage collection.  For a given section, mark
13878    it and any sections in this section's group, and all the sections
13879    which define symbols to which it refers.  */
13880 
13881 bool
_bfd_elf_gc_mark(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook)13882 _bfd_elf_gc_mark (struct bfd_link_info *info,
13883 		  asection *sec,
13884 		  elf_gc_mark_hook_fn gc_mark_hook)
13885 {
13886   bool ret;
13887   asection *group_sec, *eh_frame;
13888 
13889   sec->gc_mark = 1;
13890 
13891   /* Mark all the sections in the group.  */
13892   group_sec = elf_section_data (sec)->next_in_group;
13893   if (group_sec && !group_sec->gc_mark)
13894     if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
13895       return false;
13896 
13897   /* Look through the section relocs.  */
13898   ret = true;
13899   eh_frame = elf_eh_frame_section (sec->owner);
13900   if ((sec->flags & SEC_RELOC) != 0
13901       && sec->reloc_count > 0
13902       && sec != eh_frame)
13903     {
13904       struct elf_reloc_cookie cookie;
13905 
13906       if (!init_reloc_cookie_for_section (&cookie, info, sec))
13907 	ret = false;
13908       else
13909 	{
13910 	  for (; cookie.rel < cookie.relend; cookie.rel++)
13911 	    if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, &cookie))
13912 	      {
13913 		ret = false;
13914 		break;
13915 	      }
13916 	  fini_reloc_cookie_for_section (&cookie, sec);
13917 	}
13918     }
13919 
13920   if (ret && eh_frame && elf_fde_list (sec))
13921     {
13922       struct elf_reloc_cookie cookie;
13923 
13924       if (!init_reloc_cookie_for_section (&cookie, info, eh_frame))
13925 	ret = false;
13926       else
13927 	{
13928 	  if (!_bfd_elf_gc_mark_fdes (info, sec, eh_frame,
13929 				      gc_mark_hook, &cookie))
13930 	    ret = false;
13931 	  fini_reloc_cookie_for_section (&cookie, eh_frame);
13932 	}
13933     }
13934 
13935   eh_frame = elf_section_eh_frame_entry (sec);
13936   if (ret && eh_frame && !eh_frame->gc_mark)
13937     if (!_bfd_elf_gc_mark (info, eh_frame, gc_mark_hook))
13938       ret = false;
13939 
13940   return ret;
13941 }
13942 
13943 /* Scan and mark sections in a special or debug section group.  */
13944 
13945 static void
_bfd_elf_gc_mark_debug_special_section_group(asection * grp)13946 _bfd_elf_gc_mark_debug_special_section_group (asection *grp)
13947 {
13948   /* Point to first section of section group.  */
13949   asection *ssec;
13950   /* Used to iterate the section group.  */
13951   asection *msec;
13952 
13953   bool is_special_grp = true;
13954   bool is_debug_grp = true;
13955 
13956   /* First scan to see if group contains any section other than debug
13957      and special section.  */
13958   ssec = msec = elf_next_in_group (grp);
13959   do
13960     {
13961       if ((msec->flags & SEC_DEBUGGING) == 0)
13962 	is_debug_grp = false;
13963 
13964       if ((msec->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) != 0)
13965 	is_special_grp = false;
13966 
13967       msec = elf_next_in_group (msec);
13968     }
13969   while (msec != ssec);
13970 
13971   /* If this is a pure debug section group or pure special section group,
13972      keep all sections in this group.  */
13973   if (is_debug_grp || is_special_grp)
13974     {
13975       do
13976 	{
13977 	  msec->gc_mark = 1;
13978 	  msec = elf_next_in_group (msec);
13979 	}
13980       while (msec != ssec);
13981     }
13982 }
13983 
13984 /* Keep debug and special sections.  */
13985 
13986 bool
_bfd_elf_gc_mark_extra_sections(struct bfd_link_info * info,elf_gc_mark_hook_fn mark_hook)13987 _bfd_elf_gc_mark_extra_sections (struct bfd_link_info *info,
13988 				 elf_gc_mark_hook_fn mark_hook)
13989 {
13990   bfd *ibfd;
13991 
13992   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
13993     {
13994       asection *isec;
13995       bool some_kept;
13996       bool debug_frag_seen;
13997       bool has_kept_debug_info;
13998 
13999       if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
14000 	continue;
14001       isec = ibfd->sections;
14002       if (isec == NULL || isec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14003 	continue;
14004 
14005       /* Ensure all linker created sections are kept,
14006 	 see if any other section is already marked,
14007 	 and note if we have any fragmented debug sections.  */
14008       debug_frag_seen = some_kept = has_kept_debug_info = false;
14009       for (isec = ibfd->sections; isec != NULL; isec = isec->next)
14010 	{
14011 	  if ((isec->flags & SEC_LINKER_CREATED) != 0)
14012 	    isec->gc_mark = 1;
14013 	  else if (isec->gc_mark
14014 		   && (isec->flags & SEC_ALLOC) != 0
14015 		   && elf_section_type (isec) != SHT_NOTE)
14016 	    some_kept = true;
14017 	  else
14018 	    {
14019 	      /* Since all sections, except for backend specific ones,
14020 		 have been garbage collected, call mark_hook on this
14021 		 section if any of its linked-to sections is marked.  */
14022 	      asection *linked_to_sec;
14023 	      for (linked_to_sec = elf_linked_to_section (isec);
14024 		   linked_to_sec != NULL && !linked_to_sec->linker_mark;
14025 		   linked_to_sec = elf_linked_to_section (linked_to_sec))
14026 		{
14027 		  if (linked_to_sec->gc_mark)
14028 		    {
14029 		      if (!_bfd_elf_gc_mark (info, isec, mark_hook))
14030 			return false;
14031 		      break;
14032 		    }
14033 		  linked_to_sec->linker_mark = 1;
14034 		}
14035 	      for (linked_to_sec = elf_linked_to_section (isec);
14036 		   linked_to_sec != NULL && linked_to_sec->linker_mark;
14037 		   linked_to_sec = elf_linked_to_section (linked_to_sec))
14038 		linked_to_sec->linker_mark = 0;
14039 	    }
14040 
14041 	  if (!debug_frag_seen
14042 	      && (isec->flags & SEC_DEBUGGING)
14043 	      && startswith (isec->name, ".debug_line."))
14044 	    debug_frag_seen = true;
14045 	  else if (strcmp (bfd_section_name (isec),
14046 			   "__patchable_function_entries") == 0
14047 		   && elf_linked_to_section (isec) == NULL)
14048 	      info->callbacks->einfo (_("%F%P: %pB(%pA): error: "
14049 					"need linked-to section "
14050 					"for --gc-sections\n"),
14051 				      isec->owner, isec);
14052 	}
14053 
14054       /* If no non-note alloc section in this file will be kept, then
14055 	 we can toss out the debug and special sections.  */
14056       if (!some_kept)
14057 	continue;
14058 
14059       /* Keep debug and special sections like .comment when they are
14060 	 not part of a group.  Also keep section groups that contain
14061 	 just debug sections or special sections.  NB: Sections with
14062 	 linked-to section has been handled above.  */
14063       for (isec = ibfd->sections; isec != NULL; isec = isec->next)
14064 	{
14065 	  if ((isec->flags & SEC_GROUP) != 0)
14066 	    _bfd_elf_gc_mark_debug_special_section_group (isec);
14067 	  else if (((isec->flags & SEC_DEBUGGING) != 0
14068 		    || (isec->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0)
14069 		   && elf_next_in_group (isec) == NULL
14070 		   && elf_linked_to_section (isec) == NULL)
14071 	    isec->gc_mark = 1;
14072 	  if (isec->gc_mark && (isec->flags & SEC_DEBUGGING) != 0)
14073 	    has_kept_debug_info = true;
14074 	}
14075 
14076       /* Look for CODE sections which are going to be discarded,
14077 	 and find and discard any fragmented debug sections which
14078 	 are associated with that code section.  */
14079       if (debug_frag_seen)
14080 	for (isec = ibfd->sections; isec != NULL; isec = isec->next)
14081 	  if ((isec->flags & SEC_CODE) != 0
14082 	      && isec->gc_mark == 0)
14083 	    {
14084 	      unsigned int ilen;
14085 	      asection *dsec;
14086 
14087 	      ilen = strlen (isec->name);
14088 
14089 	      /* Association is determined by the name of the debug
14090 		 section containing the name of the code section as
14091 		 a suffix.  For example .debug_line.text.foo is a
14092 		 debug section associated with .text.foo.  */
14093 	      for (dsec = ibfd->sections; dsec != NULL; dsec = dsec->next)
14094 		{
14095 		  unsigned int dlen;
14096 
14097 		  if (dsec->gc_mark == 0
14098 		      || (dsec->flags & SEC_DEBUGGING) == 0)
14099 		    continue;
14100 
14101 		  dlen = strlen (dsec->name);
14102 
14103 		  if (dlen > ilen
14104 		      && strncmp (dsec->name + (dlen - ilen),
14105 				  isec->name, ilen) == 0)
14106 		    dsec->gc_mark = 0;
14107 		}
14108 	  }
14109 
14110       /* Mark debug sections referenced by kept debug sections.  */
14111       if (has_kept_debug_info)
14112 	for (isec = ibfd->sections; isec != NULL; isec = isec->next)
14113 	  if (isec->gc_mark
14114 	      && (isec->flags & SEC_DEBUGGING) != 0)
14115 	    if (!_bfd_elf_gc_mark (info, isec,
14116 				   elf_gc_mark_debug_section))
14117 	      return false;
14118     }
14119   return true;
14120 }
14121 
14122 static bool
elf_gc_sweep(bfd * abfd,struct bfd_link_info * info)14123 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
14124 {
14125   bfd *sub;
14126   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14127 
14128   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
14129     {
14130       asection *o;
14131 
14132       if (bfd_get_flavour (sub) != bfd_target_elf_flavour
14133 	  || elf_object_id (sub) != elf_hash_table_id (elf_hash_table (info))
14134 	  || !(*bed->relocs_compatible) (sub->xvec, abfd->xvec))
14135 	continue;
14136       o = sub->sections;
14137       if (o == NULL || o->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14138 	continue;
14139 
14140       for (o = sub->sections; o != NULL; o = o->next)
14141 	{
14142 	  /* When any section in a section group is kept, we keep all
14143 	     sections in the section group.  If the first member of
14144 	     the section group is excluded, we will also exclude the
14145 	     group section.  */
14146 	  if (o->flags & SEC_GROUP)
14147 	    {
14148 	      asection *first = elf_next_in_group (o);
14149 	      o->gc_mark = first->gc_mark;
14150 	    }
14151 
14152 	  if (o->gc_mark)
14153 	    continue;
14154 
14155 	  /* Skip sweeping sections already excluded.  */
14156 	  if (o->flags & SEC_EXCLUDE)
14157 	    continue;
14158 
14159 	  /* Since this is early in the link process, it is simple
14160 	     to remove a section from the output.  */
14161 	  o->flags |= SEC_EXCLUDE;
14162 
14163 	  if (info->print_gc_sections && o->size != 0)
14164 	    /* xgettext:c-format */
14165 	    _bfd_error_handler (_("removing unused section '%pA' in file '%pB'"),
14166 				o, sub);
14167 	}
14168     }
14169 
14170   return true;
14171 }
14172 
14173 /* Propagate collected vtable information.  This is called through
14174    elf_link_hash_traverse.  */
14175 
14176 static bool
elf_gc_propagate_vtable_entries_used(struct elf_link_hash_entry * h,void * okp)14177 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
14178 {
14179   /* Those that are not vtables.  */
14180   if (h->start_stop
14181       || h->u2.vtable == NULL
14182       || h->u2.vtable->parent == NULL)
14183     return true;
14184 
14185   /* Those vtables that do not have parents, we cannot merge.  */
14186   if (h->u2.vtable->parent == (struct elf_link_hash_entry *) -1)
14187     return true;
14188 
14189   /* If we've already been done, exit.  */
14190   if (h->u2.vtable->used && h->u2.vtable->used[-1])
14191     return true;
14192 
14193   /* Make sure the parent's table is up to date.  */
14194   elf_gc_propagate_vtable_entries_used (h->u2.vtable->parent, okp);
14195 
14196   if (h->u2.vtable->used == NULL)
14197     {
14198       /* None of this table's entries were referenced.  Re-use the
14199 	 parent's table.  */
14200       h->u2.vtable->used = h->u2.vtable->parent->u2.vtable->used;
14201       h->u2.vtable->size = h->u2.vtable->parent->u2.vtable->size;
14202     }
14203   else
14204     {
14205       size_t n;
14206       bool *cu, *pu;
14207 
14208       /* Or the parent's entries into ours.  */
14209       cu = h->u2.vtable->used;
14210       cu[-1] = true;
14211       pu = h->u2.vtable->parent->u2.vtable->used;
14212       if (pu != NULL)
14213 	{
14214 	  const struct elf_backend_data *bed;
14215 	  unsigned int log_file_align;
14216 
14217 	  bed = get_elf_backend_data (h->root.u.def.section->owner);
14218 	  log_file_align = bed->s->log_file_align;
14219 	  n = h->u2.vtable->parent->u2.vtable->size >> log_file_align;
14220 	  while (n--)
14221 	    {
14222 	      if (*pu)
14223 		*cu = true;
14224 	      pu++;
14225 	      cu++;
14226 	    }
14227 	}
14228     }
14229 
14230   return true;
14231 }
14232 
14233 struct link_info_ok
14234 {
14235   struct bfd_link_info *info;
14236   bool ok;
14237 };
14238 
14239 static bool
elf_gc_smash_unused_vtentry_relocs(struct elf_link_hash_entry * h,void * ptr)14240 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h,
14241 				    void *ptr)
14242 {
14243   asection *sec;
14244   bfd_vma hstart, hend;
14245   Elf_Internal_Rela *relstart, *relend, *rel;
14246   const struct elf_backend_data *bed;
14247   unsigned int log_file_align;
14248   struct link_info_ok *info = (struct link_info_ok *) ptr;
14249 
14250   /* Take care of both those symbols that do not describe vtables as
14251      well as those that are not loaded.  */
14252   if (h->start_stop
14253       || h->u2.vtable == NULL
14254       || h->u2.vtable->parent == NULL)
14255     return true;
14256 
14257   BFD_ASSERT (h->root.type == bfd_link_hash_defined
14258 	      || h->root.type == bfd_link_hash_defweak);
14259 
14260   sec = h->root.u.def.section;
14261   hstart = h->root.u.def.value;
14262   hend = hstart + h->size;
14263 
14264   relstart = _bfd_elf_link_info_read_relocs (sec->owner, info->info,
14265 					     sec, NULL, NULL, true);
14266   if (!relstart)
14267     return info->ok = false;
14268   bed = get_elf_backend_data (sec->owner);
14269   log_file_align = bed->s->log_file_align;
14270 
14271   relend = relstart + sec->reloc_count;
14272 
14273   for (rel = relstart; rel < relend; ++rel)
14274     if (rel->r_offset >= hstart && rel->r_offset < hend)
14275       {
14276 	/* If the entry is in use, do nothing.  */
14277 	if (h->u2.vtable->used
14278 	    && (rel->r_offset - hstart) < h->u2.vtable->size)
14279 	  {
14280 	    bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
14281 	    if (h->u2.vtable->used[entry])
14282 	      continue;
14283 	  }
14284 	/* Otherwise, kill it.  */
14285 	rel->r_offset = rel->r_info = rel->r_addend = 0;
14286       }
14287 
14288   return true;
14289 }
14290 
14291 /* Mark sections containing dynamically referenced symbols.  When
14292    building shared libraries, we must assume that any visible symbol is
14293    referenced.  */
14294 
14295 bool
bfd_elf_gc_mark_dynamic_ref_symbol(struct elf_link_hash_entry * h,void * inf)14296 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
14297 {
14298   struct bfd_link_info *info = (struct bfd_link_info *) inf;
14299   struct bfd_elf_dynamic_list *d = info->dynamic_list;
14300 
14301   if ((h->root.type == bfd_link_hash_defined
14302        || h->root.type == bfd_link_hash_defweak)
14303       && (!h->start_stop
14304 	  || h->root.ldscript_def
14305 	  || !info->start_stop_gc)
14306       && ((h->ref_dynamic && !h->forced_local)
14307 	  || ((h->def_regular || ELF_COMMON_DEF_P (h))
14308 	      && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
14309 	      && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN
14310 	      && (!bfd_link_executable (info)
14311 		  || info->gc_keep_exported
14312 		  || info->export_dynamic
14313 		  || (h->dynamic
14314 		      && d != NULL
14315 		      && (*d->match) (&d->head, NULL, h->root.root.string)))
14316 	      && (h->versioned >= versioned
14317 		  || !bfd_hide_sym_by_version (info->version_info,
14318 					       h->root.root.string)))))
14319     h->root.u.def.section->flags |= SEC_KEEP;
14320 
14321   return true;
14322 }
14323 
14324 /* Keep all sections containing symbols undefined on the command-line,
14325    and the section containing the entry symbol.  */
14326 
14327 void
_bfd_elf_gc_keep(struct bfd_link_info * info)14328 _bfd_elf_gc_keep (struct bfd_link_info *info)
14329 {
14330   struct bfd_sym_chain *sym;
14331 
14332   for (sym = info->gc_sym_list; sym != NULL; sym = sym->next)
14333     {
14334       struct elf_link_hash_entry *h;
14335 
14336       h = elf_link_hash_lookup (elf_hash_table (info), sym->name,
14337 				false, false, false);
14338 
14339       if (h != NULL
14340 	  && (h->root.type == bfd_link_hash_defined
14341 	      || h->root.type == bfd_link_hash_defweak)
14342 	  && !bfd_is_const_section (h->root.u.def.section))
14343 	h->root.u.def.section->flags |= SEC_KEEP;
14344     }
14345 }
14346 
14347 bool
bfd_elf_parse_eh_frame_entries(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)14348 bfd_elf_parse_eh_frame_entries (bfd *abfd ATTRIBUTE_UNUSED,
14349 				struct bfd_link_info *info)
14350 {
14351   bfd *ibfd = info->input_bfds;
14352 
14353   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
14354     {
14355       asection *sec;
14356       struct elf_reloc_cookie cookie;
14357 
14358       if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
14359 	continue;
14360       sec = ibfd->sections;
14361       if (sec == NULL || sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14362 	continue;
14363 
14364       if (!init_reloc_cookie (&cookie, info, ibfd))
14365 	return false;
14366 
14367       for (sec = ibfd->sections; sec; sec = sec->next)
14368 	{
14369 	  if (startswith (bfd_section_name (sec), ".eh_frame_entry")
14370 	      && init_reloc_cookie_rels (&cookie, info, ibfd, sec))
14371 	    {
14372 	      _bfd_elf_parse_eh_frame_entry (info, sec, &cookie);
14373 	      fini_reloc_cookie_rels (&cookie, sec);
14374 	    }
14375 	}
14376     }
14377   return true;
14378 }
14379 
14380 /* Do mark and sweep of unused sections.  */
14381 
14382 bool
bfd_elf_gc_sections(bfd * abfd,struct bfd_link_info * info)14383 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
14384 {
14385   bool ok = true;
14386   bfd *sub;
14387   elf_gc_mark_hook_fn gc_mark_hook;
14388   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14389   struct elf_link_hash_table *htab;
14390   struct link_info_ok info_ok;
14391 
14392   if (!bed->can_gc_sections
14393       || !is_elf_hash_table (info->hash))
14394     {
14395       _bfd_error_handler(_("warning: gc-sections option ignored"));
14396       return true;
14397     }
14398 
14399   bed->gc_keep (info);
14400   htab = elf_hash_table (info);
14401 
14402   /* Try to parse each bfd's .eh_frame section.  Point elf_eh_frame_section
14403      at the .eh_frame section if we can mark the FDEs individually.  */
14404   for (sub = info->input_bfds;
14405        info->eh_frame_hdr_type != COMPACT_EH_HDR && sub != NULL;
14406        sub = sub->link.next)
14407     {
14408       asection *sec;
14409       struct elf_reloc_cookie cookie;
14410 
14411       sec = sub->sections;
14412       if (sec == NULL || sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14413 	continue;
14414       sec = bfd_get_section_by_name (sub, ".eh_frame");
14415       while (sec && init_reloc_cookie_for_section (&cookie, info, sec))
14416 	{
14417 	  _bfd_elf_parse_eh_frame (sub, info, sec, &cookie);
14418 	  if (elf_section_data (sec)->sec_info
14419 	      && (sec->flags & SEC_LINKER_CREATED) == 0)
14420 	    elf_eh_frame_section (sub) = sec;
14421 	  fini_reloc_cookie_for_section (&cookie, sec);
14422 	  sec = bfd_get_next_section_by_name (NULL, sec);
14423 	}
14424     }
14425 
14426   /* Apply transitive closure to the vtable entry usage info.  */
14427   elf_link_hash_traverse (htab, elf_gc_propagate_vtable_entries_used, &ok);
14428   if (!ok)
14429     return false;
14430 
14431   /* Kill the vtable relocations that were not used.  */
14432   info_ok.info = info;
14433   info_ok.ok = true;
14434   elf_link_hash_traverse (htab, elf_gc_smash_unused_vtentry_relocs, &info_ok);
14435   if (!info_ok.ok)
14436     return false;
14437 
14438   /* Mark dynamically referenced symbols.  */
14439   if (htab->dynamic_sections_created || info->gc_keep_exported)
14440     elf_link_hash_traverse (htab, bed->gc_mark_dynamic_ref, info);
14441 
14442   /* Grovel through relocs to find out who stays ...  */
14443   gc_mark_hook = bed->gc_mark_hook;
14444   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
14445     {
14446       asection *o;
14447 
14448       if (bfd_get_flavour (sub) != bfd_target_elf_flavour
14449 	  || elf_object_id (sub) != elf_hash_table_id (htab)
14450 	  || !(*bed->relocs_compatible) (sub->xvec, abfd->xvec))
14451 	continue;
14452 
14453       o = sub->sections;
14454       if (o == NULL || o->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14455 	continue;
14456 
14457       /* Start at sections marked with SEC_KEEP (ref _bfd_elf_gc_keep).
14458 	 Also treat note sections as a root, if the section is not part
14459 	 of a group.  We must keep all PREINIT_ARRAY, INIT_ARRAY as
14460 	 well as FINI_ARRAY sections for ld -r.  */
14461       for (o = sub->sections; o != NULL; o = o->next)
14462 	if (!o->gc_mark
14463 	    && (o->flags & SEC_EXCLUDE) == 0
14464 	    && ((o->flags & SEC_KEEP) != 0
14465 		|| (bfd_link_relocatable (info)
14466 		    && ((elf_section_data (o)->this_hdr.sh_type
14467 			 == SHT_PREINIT_ARRAY)
14468 			|| (elf_section_data (o)->this_hdr.sh_type
14469 			    == SHT_INIT_ARRAY)
14470 			|| (elf_section_data (o)->this_hdr.sh_type
14471 			    == SHT_FINI_ARRAY)))
14472 		|| (elf_section_data (o)->this_hdr.sh_type == SHT_NOTE
14473 		    && elf_next_in_group (o) == NULL
14474 		    && elf_linked_to_section (o) == NULL)
14475 		|| ((elf_tdata (sub)->has_gnu_osabi & elf_gnu_osabi_retain)
14476 		    && (elf_section_flags (o) & SHF_GNU_RETAIN))))
14477 	  {
14478 	    if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
14479 	      return false;
14480 	  }
14481     }
14482 
14483   /* Allow the backend to mark additional target specific sections.  */
14484   bed->gc_mark_extra_sections (info, gc_mark_hook);
14485 
14486   /* ... and mark SEC_EXCLUDE for those that go.  */
14487   return elf_gc_sweep (abfd, info);
14488 }
14489 
14490 /* Called from check_relocs to record the existence of a VTINHERIT reloc.  */
14491 
14492 bool
bfd_elf_gc_record_vtinherit(bfd * abfd,asection * sec,struct elf_link_hash_entry * h,bfd_vma offset)14493 bfd_elf_gc_record_vtinherit (bfd *abfd,
14494 			     asection *sec,
14495 			     struct elf_link_hash_entry *h,
14496 			     bfd_vma offset)
14497 {
14498   struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
14499   struct elf_link_hash_entry **search, *child;
14500   size_t extsymcount;
14501   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14502 
14503   /* The sh_info field of the symtab header tells us where the
14504      external symbols start.  We don't care about the local symbols at
14505      this point.  */
14506   extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
14507   if (!elf_bad_symtab (abfd))
14508     extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
14509 
14510   sym_hashes = elf_sym_hashes (abfd);
14511   sym_hashes_end = PTR_ADD (sym_hashes, extsymcount);
14512 
14513   /* Hunt down the child symbol, which is in this section at the same
14514      offset as the relocation.  */
14515   for (search = sym_hashes; search != sym_hashes_end; ++search)
14516     {
14517       if ((child = *search) != NULL
14518 	  && (child->root.type == bfd_link_hash_defined
14519 	      || child->root.type == bfd_link_hash_defweak)
14520 	  && child->root.u.def.section == sec
14521 	  && child->root.u.def.value == offset)
14522 	goto win;
14523     }
14524 
14525   /* xgettext:c-format */
14526   _bfd_error_handler (_("%pB: %pA+%#" PRIx64 ": no symbol found for INHERIT"),
14527 		      abfd, sec, (uint64_t) offset);
14528   bfd_set_error (bfd_error_invalid_operation);
14529   return false;
14530 
14531  win:
14532   if (!child->u2.vtable)
14533     {
14534       child->u2.vtable = ((struct elf_link_virtual_table_entry *)
14535 			  bfd_zalloc (abfd, sizeof (*child->u2.vtable)));
14536       if (!child->u2.vtable)
14537 	return false;
14538     }
14539   if (!h)
14540     {
14541       /* This *should* only be the absolute section.  It could potentially
14542 	 be that someone has defined a non-global vtable though, which
14543 	 would be bad.  It isn't worth paging in the local symbols to be
14544 	 sure though; that case should simply be handled by the assembler.  */
14545 
14546       child->u2.vtable->parent = (struct elf_link_hash_entry *) -1;
14547     }
14548   else
14549     child->u2.vtable->parent = h;
14550 
14551   return true;
14552 }
14553 
14554 /* Called from check_relocs to record the existence of a VTENTRY reloc.  */
14555 
14556 bool
bfd_elf_gc_record_vtentry(bfd * abfd,asection * sec,struct elf_link_hash_entry * h,bfd_vma addend)14557 bfd_elf_gc_record_vtentry (bfd *abfd, asection *sec,
14558 			   struct elf_link_hash_entry *h,
14559 			   bfd_vma addend)
14560 {
14561   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14562   unsigned int log_file_align = bed->s->log_file_align;
14563 
14564   if (!h)
14565     {
14566       /* xgettext:c-format */
14567       _bfd_error_handler (_("%pB: section '%pA': corrupt VTENTRY entry"),
14568 			  abfd, sec);
14569       bfd_set_error (bfd_error_bad_value);
14570       return false;
14571     }
14572 
14573   if (!h->u2.vtable)
14574     {
14575       h->u2.vtable = ((struct elf_link_virtual_table_entry *)
14576 		      bfd_zalloc (abfd, sizeof (*h->u2.vtable)));
14577       if (!h->u2.vtable)
14578 	return false;
14579     }
14580 
14581   if (addend >= h->u2.vtable->size)
14582     {
14583       size_t size, bytes, file_align;
14584       bool *ptr = h->u2.vtable->used;
14585 
14586       /* While the symbol is undefined, we have to be prepared to handle
14587 	 a zero size.  */
14588       file_align = 1 << log_file_align;
14589       if (h->root.type == bfd_link_hash_undefined)
14590 	size = addend + file_align;
14591       else
14592 	{
14593 	  size = h->size;
14594 	  if (addend >= size)
14595 	    {
14596 	      /* Oops!  We've got a reference past the defined end of
14597 		 the table.  This is probably a bug -- shall we warn?  */
14598 	      size = addend + file_align;
14599 	    }
14600 	}
14601       size = (size + file_align - 1) & -file_align;
14602 
14603       /* Allocate one extra entry for use as a "done" flag for the
14604 	 consolidation pass.  */
14605       bytes = ((size >> log_file_align) + 1) * sizeof (bool);
14606 
14607       if (ptr)
14608 	{
14609 	  ptr = (bool *) bfd_realloc (ptr - 1, bytes);
14610 
14611 	  if (ptr != NULL)
14612 	    {
14613 	      size_t oldbytes;
14614 
14615 	      oldbytes = (((h->u2.vtable->size >> log_file_align) + 1)
14616 			  * sizeof (bool));
14617 	      memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
14618 	    }
14619 	}
14620       else
14621 	ptr = (bool *) bfd_zmalloc (bytes);
14622 
14623       if (ptr == NULL)
14624 	return false;
14625 
14626       /* And arrange for that done flag to be at index -1.  */
14627       h->u2.vtable->used = ptr + 1;
14628       h->u2.vtable->size = size;
14629     }
14630 
14631   h->u2.vtable->used[addend >> log_file_align] = true;
14632 
14633   return true;
14634 }
14635 
14636 /* Map an ELF section header flag to its corresponding string.  */
14637 typedef struct
14638 {
14639   char *flag_name;
14640   flagword flag_value;
14641 } elf_flags_to_name_table;
14642 
14643 static const elf_flags_to_name_table elf_flags_to_names [] =
14644 {
14645   { "SHF_WRITE", SHF_WRITE },
14646   { "SHF_ALLOC", SHF_ALLOC },
14647   { "SHF_EXECINSTR", SHF_EXECINSTR },
14648   { "SHF_MERGE", SHF_MERGE },
14649   { "SHF_STRINGS", SHF_STRINGS },
14650   { "SHF_INFO_LINK", SHF_INFO_LINK},
14651   { "SHF_LINK_ORDER", SHF_LINK_ORDER},
14652   { "SHF_OS_NONCONFORMING", SHF_OS_NONCONFORMING},
14653   { "SHF_GROUP", SHF_GROUP },
14654   { "SHF_TLS", SHF_TLS },
14655   { "SHF_MASKOS", SHF_MASKOS },
14656   { "SHF_EXCLUDE", SHF_EXCLUDE },
14657 };
14658 
14659 /* Returns TRUE if the section is to be included, otherwise FALSE.  */
14660 bool
bfd_elf_lookup_section_flags(struct bfd_link_info * info,struct flag_info * flaginfo,asection * section)14661 bfd_elf_lookup_section_flags (struct bfd_link_info *info,
14662 			      struct flag_info *flaginfo,
14663 			      asection *section)
14664 {
14665   const bfd_vma sh_flags = elf_section_flags (section);
14666 
14667   if (!flaginfo->flags_initialized)
14668     {
14669       bfd *obfd = info->output_bfd;
14670       const struct elf_backend_data *bed = get_elf_backend_data (obfd);
14671       struct flag_info_list *tf = flaginfo->flag_list;
14672       int with_hex = 0;
14673       int without_hex = 0;
14674 
14675       for (tf = flaginfo->flag_list; tf != NULL; tf = tf->next)
14676 	{
14677 	  unsigned i;
14678 	  flagword (*lookup) (char *);
14679 
14680 	  lookup = bed->elf_backend_lookup_section_flags_hook;
14681 	  if (lookup != NULL)
14682 	    {
14683 	      flagword hexval = (*lookup) ((char *) tf->name);
14684 
14685 	      if (hexval != 0)
14686 		{
14687 		  if (tf->with == with_flags)
14688 		    with_hex |= hexval;
14689 		  else if (tf->with == without_flags)
14690 		    without_hex |= hexval;
14691 		  tf->valid = true;
14692 		  continue;
14693 		}
14694 	    }
14695 	  for (i = 0; i < ARRAY_SIZE (elf_flags_to_names); ++i)
14696 	    {
14697 	      if (strcmp (tf->name, elf_flags_to_names[i].flag_name) == 0)
14698 		{
14699 		  if (tf->with == with_flags)
14700 		    with_hex |= elf_flags_to_names[i].flag_value;
14701 		  else if (tf->with == without_flags)
14702 		    without_hex |= elf_flags_to_names[i].flag_value;
14703 		  tf->valid = true;
14704 		  break;
14705 		}
14706 	    }
14707 	  if (!tf->valid)
14708 	    {
14709 	      info->callbacks->einfo
14710 		(_("unrecognized INPUT_SECTION_FLAG %s\n"), tf->name);
14711 	      return false;
14712 	    }
14713 	}
14714       flaginfo->flags_initialized = true;
14715       flaginfo->only_with_flags |= with_hex;
14716       flaginfo->not_with_flags |= without_hex;
14717     }
14718 
14719   if ((flaginfo->only_with_flags & sh_flags) != flaginfo->only_with_flags)
14720     return false;
14721 
14722   if ((flaginfo->not_with_flags & sh_flags) != 0)
14723     return false;
14724 
14725   return true;
14726 }
14727 
14728 struct alloc_got_off_arg {
14729   bfd_vma gotoff;
14730   struct bfd_link_info *info;
14731 };
14732 
14733 /* We need a special top-level link routine to convert got reference counts
14734    to real got offsets.  */
14735 
14736 static bool
elf_gc_allocate_got_offsets(struct elf_link_hash_entry * h,void * arg)14737 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
14738 {
14739   struct alloc_got_off_arg *gofarg = (struct alloc_got_off_arg *) arg;
14740   bfd *obfd = gofarg->info->output_bfd;
14741   const struct elf_backend_data *bed = get_elf_backend_data (obfd);
14742 
14743   if (h->got.refcount > 0)
14744     {
14745       h->got.offset = gofarg->gotoff;
14746       gofarg->gotoff += bed->got_elt_size (obfd, gofarg->info, h, NULL, 0);
14747     }
14748   else
14749     h->got.offset = (bfd_vma) -1;
14750 
14751   return true;
14752 }
14753 
14754 /* And an accompanying bit to work out final got entry offsets once
14755    we're done.  Should be called from final_link.  */
14756 
14757 bool
bfd_elf_gc_common_finalize_got_offsets(bfd * abfd,struct bfd_link_info * info)14758 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
14759 					struct bfd_link_info *info)
14760 {
14761   bfd *i;
14762   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14763   bfd_vma gotoff;
14764   struct alloc_got_off_arg gofarg;
14765 
14766   BFD_ASSERT (abfd == info->output_bfd);
14767 
14768   if (! is_elf_hash_table (info->hash))
14769     return false;
14770 
14771   /* The GOT offset is relative to the .got section, but the GOT header is
14772      put into the .got.plt section, if the backend uses it.  */
14773   if (bed->want_got_plt)
14774     gotoff = 0;
14775   else
14776     gotoff = bed->got_header_size;
14777 
14778   /* Do the local .got entries first.  */
14779   for (i = info->input_bfds; i; i = i->link.next)
14780     {
14781       bfd_signed_vma *local_got;
14782       size_t j, locsymcount;
14783       Elf_Internal_Shdr *symtab_hdr;
14784 
14785       if (bfd_get_flavour (i) != bfd_target_elf_flavour)
14786 	continue;
14787 
14788       local_got = elf_local_got_refcounts (i);
14789       if (!local_got)
14790 	continue;
14791 
14792       symtab_hdr = &elf_tdata (i)->symtab_hdr;
14793       if (elf_bad_symtab (i))
14794 	locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
14795       else
14796 	locsymcount = symtab_hdr->sh_info;
14797 
14798       for (j = 0; j < locsymcount; ++j)
14799 	{
14800 	  if (local_got[j] > 0)
14801 	    {
14802 	      local_got[j] = gotoff;
14803 	      gotoff += bed->got_elt_size (abfd, info, NULL, i, j);
14804 	    }
14805 	  else
14806 	    local_got[j] = (bfd_vma) -1;
14807 	}
14808     }
14809 
14810   /* Then the global .got entries.  .plt refcounts are handled by
14811      adjust_dynamic_symbol  */
14812   gofarg.gotoff = gotoff;
14813   gofarg.info = info;
14814   elf_link_hash_traverse (elf_hash_table (info),
14815 			  elf_gc_allocate_got_offsets,
14816 			  &gofarg);
14817   return true;
14818 }
14819 
14820 /* Many folk need no more in the way of final link than this, once
14821    got entry reference counting is enabled.  */
14822 
14823 bool
bfd_elf_gc_common_final_link(bfd * abfd,struct bfd_link_info * info)14824 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
14825 {
14826   if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
14827     return false;
14828 
14829   /* Invoke the regular ELF backend linker to do all the work.  */
14830   return bfd_elf_final_link (abfd, info);
14831 }
14832 
14833 bool
bfd_elf_reloc_symbol_deleted_p(bfd_vma offset,void * cookie)14834 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
14835 {
14836   struct elf_reloc_cookie *rcookie = (struct elf_reloc_cookie *) cookie;
14837 
14838   if (rcookie->bad_symtab)
14839     rcookie->rel = rcookie->rels;
14840 
14841   for (; rcookie->rel < rcookie->relend; rcookie->rel++)
14842     {
14843       unsigned long r_symndx;
14844 
14845       if (! rcookie->bad_symtab)
14846 	if (rcookie->rel->r_offset > offset)
14847 	  return false;
14848       if (rcookie->rel->r_offset != offset)
14849 	continue;
14850 
14851       r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
14852       if (r_symndx == STN_UNDEF)
14853 	return true;
14854 
14855       if (r_symndx >= rcookie->locsymcount
14856 	  || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
14857 	{
14858 	  struct elf_link_hash_entry *h;
14859 
14860 	  h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
14861 
14862 	  while (h->root.type == bfd_link_hash_indirect
14863 		 || h->root.type == bfd_link_hash_warning)
14864 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
14865 
14866 	  if ((h->root.type == bfd_link_hash_defined
14867 	       || h->root.type == bfd_link_hash_defweak)
14868 	      && (h->root.u.def.section->owner != rcookie->abfd
14869 		  || h->root.u.def.section->kept_section != NULL
14870 		  || discarded_section (h->root.u.def.section)))
14871 	    return true;
14872 	}
14873       else
14874 	{
14875 	  /* It's not a relocation against a global symbol,
14876 	     but it could be a relocation against a local
14877 	     symbol for a discarded section.  */
14878 	  asection *isec;
14879 	  Elf_Internal_Sym *isym;
14880 
14881 	  /* Need to: get the symbol; get the section.  */
14882 	  isym = &rcookie->locsyms[r_symndx];
14883 	  isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
14884 	  if (isec != NULL
14885 	      && (isec->kept_section != NULL
14886 		  || discarded_section (isec)))
14887 	    return true;
14888 	}
14889       return false;
14890     }
14891   return false;
14892 }
14893 
14894 /* Discard unneeded references to discarded sections.
14895    Returns -1 on error, 1 if any section's size was changed, 0 if
14896    nothing changed.  This function assumes that the relocations are in
14897    sorted order, which is true for all known assemblers.  */
14898 
14899 int
bfd_elf_discard_info(bfd * output_bfd,struct bfd_link_info * info)14900 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
14901 {
14902   struct elf_reloc_cookie cookie;
14903   asection *o;
14904   bfd *abfd;
14905   int changed = 0;
14906 
14907   if (info->traditional_format
14908       || !is_elf_hash_table (info->hash))
14909     return 0;
14910 
14911   o = bfd_get_section_by_name (output_bfd, ".stab");
14912   if (o != NULL)
14913     {
14914       asection *i;
14915 
14916       for (i = o->map_head.s; i != NULL; i = i->map_head.s)
14917 	{
14918 	  if (i->size == 0
14919 	      || i->reloc_count == 0
14920 	      || i->sec_info_type != SEC_INFO_TYPE_STABS)
14921 	    continue;
14922 
14923 	  abfd = i->owner;
14924 	  if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
14925 	    continue;
14926 
14927 	  if (!init_reloc_cookie_for_section (&cookie, info, i))
14928 	    return -1;
14929 
14930 	  if (_bfd_discard_section_stabs (abfd, i,
14931 					  elf_section_data (i)->sec_info,
14932 					  bfd_elf_reloc_symbol_deleted_p,
14933 					  &cookie))
14934 	    changed = 1;
14935 
14936 	  fini_reloc_cookie_for_section (&cookie, i);
14937 	}
14938     }
14939 
14940   o = NULL;
14941   if (info->eh_frame_hdr_type != COMPACT_EH_HDR)
14942     o = bfd_get_section_by_name (output_bfd, ".eh_frame");
14943   if (o != NULL)
14944     {
14945       asection *i;
14946       int eh_changed = 0;
14947       unsigned int eh_alignment;  /* Octets.  */
14948 
14949       for (i = o->map_head.s; i != NULL; i = i->map_head.s)
14950 	{
14951 	  if (i->size == 0)
14952 	    continue;
14953 
14954 	  abfd = i->owner;
14955 	  if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
14956 	    continue;
14957 
14958 	  if (!init_reloc_cookie_for_section (&cookie, info, i))
14959 	    return -1;
14960 
14961 	  _bfd_elf_parse_eh_frame (abfd, info, i, &cookie);
14962 	  if (_bfd_elf_discard_section_eh_frame (abfd, info, i,
14963 						 bfd_elf_reloc_symbol_deleted_p,
14964 						 &cookie))
14965 	    {
14966 	      eh_changed = 1;
14967 	      if (i->size != i->rawsize)
14968 		changed = 1;
14969 	    }
14970 
14971 	  fini_reloc_cookie_for_section (&cookie, i);
14972 	}
14973 
14974       eh_alignment = ((1 << o->alignment_power)
14975 		      * bfd_octets_per_byte (output_bfd, o));
14976       /* Skip over zero terminator, and prevent empty sections from
14977 	 adding alignment padding at the end.  */
14978       for (i = o->map_tail.s; i != NULL; i = i->map_tail.s)
14979 	if (i->size == 0)
14980 	  i->flags |= SEC_EXCLUDE;
14981 	else if (i->size > 4)
14982 	  break;
14983       /* The last non-empty eh_frame section doesn't need padding.  */
14984       if (i != NULL)
14985 	i = i->map_tail.s;
14986       /* Any prior sections must pad the last FDE out to the output
14987 	 section alignment.  Otherwise we might have zero padding
14988 	 between sections, which would be seen as a terminator.  */
14989       for (; i != NULL; i = i->map_tail.s)
14990 	if (i->size == 4)
14991 	  /* All but the last zero terminator should have been removed.  */
14992 	  BFD_FAIL ();
14993 	else
14994 	  {
14995 	    bfd_size_type size
14996 	      = (i->size + eh_alignment - 1) & -eh_alignment;
14997 	    if (i->size != size)
14998 	      {
14999 		i->size = size;
15000 		changed = 1;
15001 		eh_changed = 1;
15002 	      }
15003 	  }
15004       if (eh_changed)
15005 	elf_link_hash_traverse (elf_hash_table (info),
15006 				_bfd_elf_adjust_eh_frame_global_symbol, NULL);
15007     }
15008 
15009   o = bfd_get_section_by_name (output_bfd, ".sframe");
15010   if (o != NULL)
15011     {
15012       asection *i;
15013 
15014       for (i = o->map_head.s; i != NULL; i = i->map_head.s)
15015 	{
15016 	  if (i->size == 0)
15017 	    continue;
15018 
15019 	  abfd = i->owner;
15020 	  if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
15021 	    continue;
15022 
15023 	  if (!init_reloc_cookie_for_section (&cookie, info, i))
15024 	    return -1;
15025 
15026 	  if (_bfd_elf_parse_sframe (abfd, info, i, &cookie))
15027 	    {
15028 	      if (_bfd_elf_discard_section_sframe (i,
15029 						   bfd_elf_reloc_symbol_deleted_p,
15030 						   &cookie))
15031 		{
15032 		  if (i->size != i->rawsize)
15033 		    changed = 1;
15034 		}
15035 	    }
15036 	  fini_reloc_cookie_for_section (&cookie, i);
15037 	}
15038       /* Update the reference to the output .sframe section.  Used to
15039 	 determine later if PT_GNU_SFRAME segment is to be generated.  */
15040       if (!_bfd_elf_set_section_sframe (output_bfd, info))
15041 	return -1;
15042     }
15043 
15044   for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next)
15045     {
15046       const struct elf_backend_data *bed;
15047       asection *s;
15048 
15049       if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
15050 	continue;
15051       s = abfd->sections;
15052       if (s == NULL || s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
15053 	continue;
15054 
15055       bed = get_elf_backend_data (abfd);
15056 
15057       if (bed->elf_backend_discard_info != NULL)
15058 	{
15059 	  if (!init_reloc_cookie (&cookie, info, abfd))
15060 	    return -1;
15061 
15062 	  if ((*bed->elf_backend_discard_info) (abfd, &cookie, info))
15063 	    changed = 1;
15064 
15065 	  fini_reloc_cookie (&cookie, abfd);
15066 	}
15067     }
15068 
15069   if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
15070     _bfd_elf_end_eh_frame_parsing (info);
15071 
15072   if (info->eh_frame_hdr_type
15073       && !bfd_link_relocatable (info)
15074       && _bfd_elf_discard_section_eh_frame_hdr (info))
15075     changed = 1;
15076 
15077   return changed;
15078 }
15079 
15080 bool
_bfd_elf_section_already_linked(bfd * abfd,asection * sec,struct bfd_link_info * info)15081 _bfd_elf_section_already_linked (bfd *abfd,
15082 				 asection *sec,
15083 				 struct bfd_link_info *info)
15084 {
15085   flagword flags;
15086   const char *name, *key;
15087   struct bfd_section_already_linked *l;
15088   struct bfd_section_already_linked_hash_entry *already_linked_list;
15089 
15090   if (sec->output_section == bfd_abs_section_ptr)
15091     return false;
15092 
15093   flags = sec->flags;
15094 
15095   /* Return if it isn't a linkonce section.  A comdat group section
15096      also has SEC_LINK_ONCE set.  */
15097   if ((flags & SEC_LINK_ONCE) == 0)
15098     return false;
15099 
15100   /* Don't put group member sections on our list of already linked
15101      sections.  They are handled as a group via their group section.  */
15102   if (elf_sec_group (sec) != NULL)
15103     return false;
15104 
15105   /* For a SHT_GROUP section, use the group signature as the key.  */
15106   name = sec->name;
15107   if ((flags & SEC_GROUP) != 0
15108       && elf_next_in_group (sec) != NULL
15109       && elf_group_name (elf_next_in_group (sec)) != NULL)
15110     key = elf_group_name (elf_next_in_group (sec));
15111   else
15112     {
15113       /* Otherwise we should have a .gnu.linkonce.<type>.<key> section.  */
15114       if (startswith (name, ".gnu.linkonce.")
15115 	  && (key = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
15116 	key++;
15117       else
15118 	/* Must be a user linkonce section that doesn't follow gcc's
15119 	   naming convention.  In this case we won't be matching
15120 	   single member groups.  */
15121 	key = name;
15122     }
15123 
15124   already_linked_list = bfd_section_already_linked_table_lookup (key);
15125 
15126   for (l = already_linked_list->entry; l != NULL; l = l->next)
15127     {
15128       /* We may have 2 different types of sections on the list: group
15129 	 sections with a signature of <key> (<key> is some string),
15130 	 and linkonce sections named .gnu.linkonce.<type>.<key>.
15131 	 Match like sections.  LTO plugin sections are an exception.
15132 	 They are always named .gnu.linkonce.t.<key> and match either
15133 	 type of section.  */
15134       if (((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
15135 	   && ((flags & SEC_GROUP) != 0
15136 	       || strcmp (name, l->sec->name) == 0))
15137 	  || (l->sec->owner->flags & BFD_PLUGIN) != 0
15138 	  || (sec->owner->flags & BFD_PLUGIN) != 0)
15139 	{
15140 	  /* The section has already been linked.  See if we should
15141 	     issue a warning.  */
15142 	  if (!_bfd_handle_already_linked (sec, l, info))
15143 	    return false;
15144 
15145 	  if (flags & SEC_GROUP)
15146 	    {
15147 	      asection *first = elf_next_in_group (sec);
15148 	      asection *s = first;
15149 
15150 	      while (s != NULL)
15151 		{
15152 		  s->output_section = bfd_abs_section_ptr;
15153 		  /* Record which group discards it.  */
15154 		  s->kept_section = l->sec;
15155 		  s = elf_next_in_group (s);
15156 		  /* These lists are circular.  */
15157 		  if (s == first)
15158 		    break;
15159 		}
15160 	    }
15161 
15162 	  return true;
15163 	}
15164     }
15165 
15166   /* A single member comdat group section may be discarded by a
15167      linkonce section and vice versa.  */
15168   if ((flags & SEC_GROUP) != 0)
15169     {
15170       asection *first = elf_next_in_group (sec);
15171 
15172       if (first != NULL && elf_next_in_group (first) == first)
15173 	/* Check this single member group against linkonce sections.  */
15174 	for (l = already_linked_list->entry; l != NULL; l = l->next)
15175 	  if ((l->sec->flags & SEC_GROUP) == 0
15176 	      && bfd_elf_match_symbols_in_sections (l->sec, first, info))
15177 	    {
15178 	      first->output_section = bfd_abs_section_ptr;
15179 	      first->kept_section = l->sec;
15180 	      sec->output_section = bfd_abs_section_ptr;
15181 	      break;
15182 	    }
15183     }
15184   else
15185     /* Check this linkonce section against single member groups.  */
15186     for (l = already_linked_list->entry; l != NULL; l = l->next)
15187       if (l->sec->flags & SEC_GROUP)
15188 	{
15189 	  asection *first = elf_next_in_group (l->sec);
15190 
15191 	  if (first != NULL
15192 	      && elf_next_in_group (first) == first
15193 	      && bfd_elf_match_symbols_in_sections (first, sec, info))
15194 	    {
15195 	      sec->output_section = bfd_abs_section_ptr;
15196 	      sec->kept_section = first;
15197 	      break;
15198 	    }
15199 	}
15200 
15201   /* Do not complain on unresolved relocations in `.gnu.linkonce.r.F'
15202      referencing its discarded `.gnu.linkonce.t.F' counterpart - g++-3.4
15203      specific as g++-4.x is using COMDAT groups (without the `.gnu.linkonce'
15204      prefix) instead.  `.gnu.linkonce.r.*' were the `.rodata' part of its
15205      matching `.gnu.linkonce.t.*'.  If `.gnu.linkonce.r.F' is not discarded
15206      but its `.gnu.linkonce.t.F' is discarded means we chose one-only
15207      `.gnu.linkonce.t.F' section from a different bfd not requiring any
15208      `.gnu.linkonce.r.F'.  Thus `.gnu.linkonce.r.F' should be discarded.
15209      The reverse order cannot happen as there is never a bfd with only the
15210      `.gnu.linkonce.r.F' section.  The order of sections in a bfd does not
15211      matter as here were are looking only for cross-bfd sections.  */
15212 
15213   if ((flags & SEC_GROUP) == 0 && startswith (name, ".gnu.linkonce.r."))
15214     for (l = already_linked_list->entry; l != NULL; l = l->next)
15215       if ((l->sec->flags & SEC_GROUP) == 0
15216 	  && startswith (l->sec->name, ".gnu.linkonce.t."))
15217 	{
15218 	  if (abfd != l->sec->owner)
15219 	    sec->output_section = bfd_abs_section_ptr;
15220 	  break;
15221 	}
15222 
15223   /* This is the first section with this name.  Record it.  */
15224   if (!bfd_section_already_linked_table_insert (already_linked_list, sec))
15225     info->callbacks->einfo (_("%F%P: already_linked_table: %E\n"));
15226   return sec->output_section == bfd_abs_section_ptr;
15227 }
15228 
15229 bool
_bfd_elf_common_definition(Elf_Internal_Sym * sym)15230 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
15231 {
15232   return sym->st_shndx == SHN_COMMON;
15233 }
15234 
15235 unsigned int
_bfd_elf_common_section_index(asection * sec ATTRIBUTE_UNUSED)15236 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
15237 {
15238   return SHN_COMMON;
15239 }
15240 
15241 asection *
_bfd_elf_common_section(asection * sec ATTRIBUTE_UNUSED)15242 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
15243 {
15244   return bfd_com_section_ptr;
15245 }
15246 
15247 bfd_vma
_bfd_elf_default_got_elt_size(bfd * abfd,struct bfd_link_info * info ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h ATTRIBUTE_UNUSED,bfd * ibfd ATTRIBUTE_UNUSED,unsigned long symndx ATTRIBUTE_UNUSED)15248 _bfd_elf_default_got_elt_size (bfd *abfd,
15249 			       struct bfd_link_info *info ATTRIBUTE_UNUSED,
15250 			       struct elf_link_hash_entry *h ATTRIBUTE_UNUSED,
15251 			       bfd *ibfd ATTRIBUTE_UNUSED,
15252 			       unsigned long symndx ATTRIBUTE_UNUSED)
15253 {
15254   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
15255   return bed->s->arch_size / 8;
15256 }
15257 
15258 /* Routines to support the creation of dynamic relocs.  */
15259 
15260 /* Returns the name of the dynamic reloc section associated with SEC.  */
15261 
15262 static const char *
get_dynamic_reloc_section_name(bfd * abfd,asection * sec,bool is_rela)15263 get_dynamic_reloc_section_name (bfd *       abfd,
15264 				asection *  sec,
15265 				bool is_rela)
15266 {
15267   char *name;
15268   const char *old_name = bfd_section_name (sec);
15269   const char *prefix = is_rela ? ".rela" : ".rel";
15270 
15271   if (old_name == NULL)
15272     return NULL;
15273 
15274   name = bfd_alloc (abfd, strlen (prefix) + strlen (old_name) + 1);
15275   sprintf (name, "%s%s", prefix, old_name);
15276 
15277   return name;
15278 }
15279 
15280 /* Returns the dynamic reloc section associated with SEC.
15281    If necessary compute the name of the dynamic reloc section based
15282    on SEC's name (looked up in ABFD's string table) and the setting
15283    of IS_RELA.  */
15284 
15285 asection *
_bfd_elf_get_dynamic_reloc_section(bfd * abfd,asection * sec,bool is_rela)15286 _bfd_elf_get_dynamic_reloc_section (bfd *abfd,
15287 				    asection *sec,
15288 				    bool is_rela)
15289 {
15290   asection *reloc_sec = elf_section_data (sec)->sreloc;
15291 
15292   if (reloc_sec == NULL)
15293     {
15294       const char *name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
15295 
15296       if (name != NULL)
15297 	{
15298 	  reloc_sec = bfd_get_linker_section (abfd, name);
15299 
15300 	  if (reloc_sec != NULL)
15301 	    elf_section_data (sec)->sreloc = reloc_sec;
15302 	}
15303     }
15304 
15305   return reloc_sec;
15306 }
15307 
15308 /* Returns the dynamic reloc section associated with SEC.  If the
15309    section does not exist it is created and attached to the DYNOBJ
15310    bfd and stored in the SRELOC field of SEC's elf_section_data
15311    structure.
15312 
15313    ALIGNMENT is the alignment for the newly created section and
15314    IS_RELA defines whether the name should be .rela.<SEC's name>
15315    or .rel.<SEC's name>.  The section name is looked up in the
15316    string table associated with ABFD.  */
15317 
15318 asection *
_bfd_elf_make_dynamic_reloc_section(asection * sec,bfd * dynobj,unsigned int alignment,bfd * abfd,bool is_rela)15319 _bfd_elf_make_dynamic_reloc_section (asection *sec,
15320 				     bfd *dynobj,
15321 				     unsigned int alignment,
15322 				     bfd *abfd,
15323 				     bool is_rela)
15324 {
15325   asection * reloc_sec = elf_section_data (sec)->sreloc;
15326 
15327   if (reloc_sec == NULL)
15328     {
15329       const char * name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
15330 
15331       if (name == NULL)
15332 	return NULL;
15333 
15334       reloc_sec = bfd_get_linker_section (dynobj, name);
15335 
15336       if (reloc_sec == NULL)
15337 	{
15338 	  flagword flags = (SEC_HAS_CONTENTS | SEC_READONLY
15339 			    | SEC_IN_MEMORY | SEC_LINKER_CREATED);
15340 	  if ((sec->flags & SEC_ALLOC) != 0)
15341 	    flags |= SEC_ALLOC | SEC_LOAD;
15342 
15343 	  reloc_sec = bfd_make_section_anyway_with_flags (dynobj, name, flags);
15344 	  if (reloc_sec != NULL)
15345 	    {
15346 	      /* _bfd_elf_get_sec_type_attr chooses a section type by
15347 		 name.  Override as it may be wrong, eg. for a user
15348 		 section named "auto" we'll get ".relauto" which is
15349 		 seen to be a .rela section.  */
15350 	      elf_section_type (reloc_sec) = is_rela ? SHT_RELA : SHT_REL;
15351 	      if (!bfd_set_section_alignment (reloc_sec, alignment))
15352 		reloc_sec = NULL;
15353 	    }
15354 	}
15355 
15356       elf_section_data (sec)->sreloc = reloc_sec;
15357     }
15358 
15359   return reloc_sec;
15360 }
15361 
15362 /* Copy the ELF symbol type and other attributes for a linker script
15363    assignment from HSRC to HDEST.  Generally this should be treated as
15364    if we found a strong non-dynamic definition for HDEST (except that
15365    ld ignores multiple definition errors).  */
15366 void
_bfd_elf_copy_link_hash_symbol_type(bfd * abfd,struct bfd_link_hash_entry * hdest,struct bfd_link_hash_entry * hsrc)15367 _bfd_elf_copy_link_hash_symbol_type (bfd *abfd,
15368 				     struct bfd_link_hash_entry *hdest,
15369 				     struct bfd_link_hash_entry *hsrc)
15370 {
15371   struct elf_link_hash_entry *ehdest = (struct elf_link_hash_entry *) hdest;
15372   struct elf_link_hash_entry *ehsrc = (struct elf_link_hash_entry *) hsrc;
15373   Elf_Internal_Sym isym;
15374 
15375   ehdest->type = ehsrc->type;
15376   ehdest->target_internal = ehsrc->target_internal;
15377 
15378   isym.st_other = ehsrc->other;
15379   elf_merge_st_other (abfd, ehdest, isym.st_other, NULL, true, false);
15380 }
15381 
15382 /* Append a RELA relocation REL to section S in BFD.  */
15383 
15384 void
elf_append_rela(bfd * abfd,asection * s,Elf_Internal_Rela * rel)15385 elf_append_rela (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
15386 {
15387   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
15388   bfd_byte *loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rela);
15389   BFD_ASSERT (loc + bed->s->sizeof_rela <= s->contents + s->size);
15390   bed->s->swap_reloca_out (abfd, rel, loc);
15391 }
15392 
15393 /* Append a REL relocation REL to section S in BFD.  */
15394 
15395 void
elf_append_rel(bfd * abfd,asection * s,Elf_Internal_Rela * rel)15396 elf_append_rel (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
15397 {
15398   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
15399   bfd_byte *loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rel);
15400   BFD_ASSERT (loc + bed->s->sizeof_rel <= s->contents + s->size);
15401   bed->s->swap_reloc_out (abfd, rel, loc);
15402 }
15403 
15404 /* Define __start, __stop, .startof. or .sizeof. symbol.  */
15405 
15406 struct bfd_link_hash_entry *
bfd_elf_define_start_stop(struct bfd_link_info * info,const char * symbol,asection * sec)15407 bfd_elf_define_start_stop (struct bfd_link_info *info,
15408 			   const char *symbol, asection *sec)
15409 {
15410   struct elf_link_hash_entry *h;
15411 
15412   h = elf_link_hash_lookup (elf_hash_table (info), symbol,
15413 			    false, false, true);
15414   /* NB: Common symbols will be turned into definition later.  */
15415   if (h != NULL
15416       && !h->root.ldscript_def
15417       && (h->root.type == bfd_link_hash_undefined
15418 	  || h->root.type == bfd_link_hash_undefweak
15419 	  || ((h->ref_regular || h->def_dynamic)
15420 	      && !h->def_regular
15421 	      && h->root.type != bfd_link_hash_common)))
15422     {
15423       bool was_dynamic = h->ref_dynamic || h->def_dynamic;
15424       h->verinfo.verdef = NULL;
15425       h->root.type = bfd_link_hash_defined;
15426       h->root.u.def.section = sec;
15427       h->root.u.def.value = 0;
15428       h->def_regular = 1;
15429       h->def_dynamic = 0;
15430       h->start_stop = 1;
15431       h->u2.start_stop_section = sec;
15432       if (symbol[0] == '.')
15433 	{
15434 	  /* .startof. and .sizeof. symbols are local.  */
15435 	  const struct elf_backend_data *bed;
15436 	  bed = get_elf_backend_data (info->output_bfd);
15437 	  (*bed->elf_backend_hide_symbol) (info, h, true);
15438 	}
15439       else
15440 	{
15441 	  if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
15442 	    h->other = ((h->other & ~ELF_ST_VISIBILITY (-1))
15443 			| info->start_stop_visibility);
15444 	  if (was_dynamic)
15445 	    bfd_elf_link_record_dynamic_symbol (info, h);
15446 	}
15447       return &h->root;
15448     }
15449   return NULL;
15450 }
15451 
15452 /* Find dynamic relocs for H that apply to read-only sections.  */
15453 
15454 asection *
_bfd_elf_readonly_dynrelocs(struct elf_link_hash_entry * h)15455 _bfd_elf_readonly_dynrelocs (struct elf_link_hash_entry *h)
15456 {
15457   struct elf_dyn_relocs *p;
15458 
15459   for (p = h->dyn_relocs; p != NULL; p = p->next)
15460     {
15461       asection *s = p->sec->output_section;
15462 
15463       if (s != NULL && (s->flags & SEC_READONLY) != 0)
15464 	return p->sec;
15465     }
15466   return NULL;
15467 }
15468 
15469 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
15470    read-only sections.  */
15471 
15472 bool
_bfd_elf_maybe_set_textrel(struct elf_link_hash_entry * h,void * inf)15473 _bfd_elf_maybe_set_textrel (struct elf_link_hash_entry *h, void *inf)
15474 {
15475   asection *sec;
15476 
15477   if (h->root.type == bfd_link_hash_indirect)
15478     return true;
15479 
15480   sec = _bfd_elf_readonly_dynrelocs (h);
15481   if (sec != NULL)
15482     {
15483       struct bfd_link_info *info = (struct bfd_link_info *) inf;
15484 
15485       info->flags |= DF_TEXTREL;
15486       /* xgettext:c-format */
15487       info->callbacks->minfo (_("%pB: dynamic relocation against `%pT' "
15488 				"in read-only section `%pA'\n"),
15489 			      sec->owner, h->root.root.string, sec);
15490 
15491       if (bfd_link_textrel_check (info))
15492 	/* xgettext:c-format */
15493 	info->callbacks->einfo (_("%P: %pB: warning: relocation against `%s' "
15494 				  "in read-only section `%pA'\n"),
15495 				sec->owner, h->root.root.string, sec);
15496 
15497       /* Not an error, just cut short the traversal.  */
15498       return false;
15499     }
15500   return true;
15501 }
15502 
15503 /* Add dynamic tags.  */
15504 
15505 bool
_bfd_elf_add_dynamic_tags(bfd * output_bfd,struct bfd_link_info * info,bool need_dynamic_reloc)15506 _bfd_elf_add_dynamic_tags (bfd *output_bfd, struct bfd_link_info *info,
15507 			   bool need_dynamic_reloc)
15508 {
15509   struct elf_link_hash_table *htab = elf_hash_table (info);
15510 
15511   if (htab->dynamic_sections_created)
15512     {
15513       /* Add some entries to the .dynamic section.  We fill in the
15514 	 values later, in finish_dynamic_sections, but we must add
15515 	 the entries now so that we get the correct size for the
15516 	 .dynamic section.  The DT_DEBUG entry is filled in by the
15517 	 dynamic linker and used by the debugger.  */
15518 #define add_dynamic_entry(TAG, VAL) \
15519   _bfd_elf_add_dynamic_entry (info, TAG, VAL)
15520 
15521       const struct elf_backend_data *bed
15522 	= get_elf_backend_data (output_bfd);
15523 
15524       if (bfd_link_executable (info))
15525 	{
15526 	  if (!add_dynamic_entry (DT_DEBUG, 0))
15527 	    return false;
15528 	}
15529 
15530       if (htab->dt_pltgot_required || htab->splt->size != 0)
15531 	{
15532 	  /* DT_PLTGOT is used by prelink even if there is no PLT
15533 	     relocation.  */
15534 	  if (!add_dynamic_entry (DT_PLTGOT, 0))
15535 	    return false;
15536 	}
15537 
15538       if (htab->dt_jmprel_required || htab->srelplt->size != 0)
15539 	{
15540 	  if (!add_dynamic_entry (DT_PLTRELSZ, 0)
15541 	      || !add_dynamic_entry (DT_PLTREL,
15542 				     (bed->rela_plts_and_copies_p
15543 				      ? DT_RELA : DT_REL))
15544 	      || !add_dynamic_entry (DT_JMPREL, 0))
15545 	    return false;
15546 	}
15547 
15548       if (htab->tlsdesc_plt
15549 	  && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
15550 	      || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
15551 	return false;
15552 
15553       if (need_dynamic_reloc)
15554 	{
15555 	  if (bed->rela_plts_and_copies_p)
15556 	    {
15557 	      if (!add_dynamic_entry (DT_RELA, 0)
15558 		  || !add_dynamic_entry (DT_RELASZ, 0)
15559 		  || !add_dynamic_entry (DT_RELAENT,
15560 					 bed->s->sizeof_rela))
15561 		return false;
15562 	    }
15563 	  else
15564 	    {
15565 	      if (!add_dynamic_entry (DT_REL, 0)
15566 		  || !add_dynamic_entry (DT_RELSZ, 0)
15567 		  || !add_dynamic_entry (DT_RELENT,
15568 					 bed->s->sizeof_rel))
15569 		return false;
15570 	    }
15571 
15572 	  /* If any dynamic relocs apply to a read-only section,
15573 	     then we need a DT_TEXTREL entry.  */
15574 	  if ((info->flags & DF_TEXTREL) == 0)
15575 	    elf_link_hash_traverse (htab, _bfd_elf_maybe_set_textrel,
15576 				    info);
15577 
15578 	  if ((info->flags & DF_TEXTREL) != 0)
15579 	    {
15580 	      if (htab->ifunc_resolvers)
15581 		info->callbacks->einfo
15582 		  (_("%P: warning: GNU indirect functions with DT_TEXTREL "
15583 		     "may result in a segfault at runtime; recompile with %s\n"),
15584 		   bfd_link_dll (info) ? "-fPIC" : "-fPIE");
15585 
15586 	      if (!add_dynamic_entry (DT_TEXTREL, 0))
15587 		return false;
15588 	    }
15589 	}
15590     }
15591 #undef add_dynamic_entry
15592 
15593   return true;
15594 }
15595