xref: /netbsd-src/external/gpl3/gdb/dist/bfd/linker.c (revision cef8759bd76c1b621f8eab8faa6f208faabc2e15)
1 /* linker.c -- BFD linker routines
2    Copyright (C) 1993-2019 Free Software Foundation, Inc.
3    Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
4 
5    This file is part of BFD, the Binary File Descriptor library.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 #include "sysdep.h"
23 #include "bfd.h"
24 #include "libbfd.h"
25 #include "bfdlink.h"
26 #include "genlink.h"
27 
28 /*
29 SECTION
30 	Linker Functions
31 
32 @cindex Linker
33 	The linker uses three special entry points in the BFD target
34 	vector.  It is not necessary to write special routines for
35 	these entry points when creating a new BFD back end, since
36 	generic versions are provided.  However, writing them can
37 	speed up linking and make it use significantly less runtime
38 	memory.
39 
40 	The first routine creates a hash table used by the other
41 	routines.  The second routine adds the symbols from an object
42 	file to the hash table.  The third routine takes all the
43 	object files and links them together to create the output
44 	file.  These routines are designed so that the linker proper
45 	does not need to know anything about the symbols in the object
46 	files that it is linking.  The linker merely arranges the
47 	sections as directed by the linker script and lets BFD handle
48 	the details of symbols and relocs.
49 
50 	The second routine and third routines are passed a pointer to
51 	a <<struct bfd_link_info>> structure (defined in
52 	<<bfdlink.h>>) which holds information relevant to the link,
53 	including the linker hash table (which was created by the
54 	first routine) and a set of callback functions to the linker
55 	proper.
56 
57 	The generic linker routines are in <<linker.c>>, and use the
58 	header file <<genlink.h>>.  As of this writing, the only back
59 	ends which have implemented versions of these routines are
60 	a.out (in <<aoutx.h>>) and ECOFF (in <<ecoff.c>>).  The a.out
61 	routines are used as examples throughout this section.
62 
63 @menu
64 @* Creating a Linker Hash Table::
65 @* Adding Symbols to the Hash Table::
66 @* Performing the Final Link::
67 @end menu
68 
69 INODE
70 Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions
71 SUBSECTION
72 	Creating a linker hash table
73 
74 @cindex _bfd_link_hash_table_create in target vector
75 @cindex target vector (_bfd_link_hash_table_create)
76 	The linker routines must create a hash table, which must be
77 	derived from <<struct bfd_link_hash_table>> described in
78 	<<bfdlink.c>>.  @xref{Hash Tables}, for information on how to
79 	create a derived hash table.  This entry point is called using
80 	the target vector of the linker output file.
81 
82 	The <<_bfd_link_hash_table_create>> entry point must allocate
83 	and initialize an instance of the desired hash table.  If the
84 	back end does not require any additional information to be
85 	stored with the entries in the hash table, the entry point may
86 	simply create a <<struct bfd_link_hash_table>>.  Most likely,
87 	however, some additional information will be needed.
88 
89 	For example, with each entry in the hash table the a.out
90 	linker keeps the index the symbol has in the final output file
91 	(this index number is used so that when doing a relocatable
92 	link the symbol index used in the output file can be quickly
93 	filled in when copying over a reloc).  The a.out linker code
94 	defines the required structures and functions for a hash table
95 	derived from <<struct bfd_link_hash_table>>.  The a.out linker
96 	hash table is created by the function
97 	<<NAME(aout,link_hash_table_create)>>; it simply allocates
98 	space for the hash table, initializes it, and returns a
99 	pointer to it.
100 
101 	When writing the linker routines for a new back end, you will
102 	generally not know exactly which fields will be required until
103 	you have finished.  You should simply create a new hash table
104 	which defines no additional fields, and then simply add fields
105 	as they become necessary.
106 
107 INODE
108 Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions
109 SUBSECTION
110 	Adding symbols to the hash table
111 
112 @cindex _bfd_link_add_symbols in target vector
113 @cindex target vector (_bfd_link_add_symbols)
114 	The linker proper will call the <<_bfd_link_add_symbols>>
115 	entry point for each object file or archive which is to be
116 	linked (typically these are the files named on the command
117 	line, but some may also come from the linker script).  The
118 	entry point is responsible for examining the file.  For an
119 	object file, BFD must add any relevant symbol information to
120 	the hash table.  For an archive, BFD must determine which
121 	elements of the archive should be used and adding them to the
122 	link.
123 
124 	The a.out version of this entry point is
125 	<<NAME(aout,link_add_symbols)>>.
126 
127 @menu
128 @* Differing file formats::
129 @* Adding symbols from an object file::
130 @* Adding symbols from an archive::
131 @end menu
132 
133 INODE
134 Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table
135 SUBSUBSECTION
136 	Differing file formats
137 
138 	Normally all the files involved in a link will be of the same
139 	format, but it is also possible to link together different
140 	format object files, and the back end must support that.  The
141 	<<_bfd_link_add_symbols>> entry point is called via the target
142 	vector of the file to be added.  This has an important
143 	consequence: the function may not assume that the hash table
144 	is the type created by the corresponding
145 	<<_bfd_link_hash_table_create>> vector.  All the
146 	<<_bfd_link_add_symbols>> function can assume about the hash
147 	table is that it is derived from <<struct
148 	bfd_link_hash_table>>.
149 
150 	Sometimes the <<_bfd_link_add_symbols>> function must store
151 	some information in the hash table entry to be used by the
152 	<<_bfd_final_link>> function.  In such a case the output bfd
153 	xvec must be checked to make sure that the hash table was
154 	created by an object file of the same format.
155 
156 	The <<_bfd_final_link>> routine must be prepared to handle a
157 	hash entry without any extra information added by the
158 	<<_bfd_link_add_symbols>> function.  A hash entry without
159 	extra information will also occur when the linker script
160 	directs the linker to create a symbol.  Note that, regardless
161 	of how a hash table entry is added, all the fields will be
162 	initialized to some sort of null value by the hash table entry
163 	initialization function.
164 
165 	See <<ecoff_link_add_externals>> for an example of how to
166 	check the output bfd before saving information (in this
167 	case, the ECOFF external symbol debugging information) in a
168 	hash table entry.
169 
170 INODE
171 Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table
172 SUBSUBSECTION
173 	Adding symbols from an object file
174 
175 	When the <<_bfd_link_add_symbols>> routine is passed an object
176 	file, it must add all externally visible symbols in that
177 	object file to the hash table.  The actual work of adding the
178 	symbol to the hash table is normally handled by the function
179 	<<_bfd_generic_link_add_one_symbol>>.  The
180 	<<_bfd_link_add_symbols>> routine is responsible for reading
181 	all the symbols from the object file and passing the correct
182 	information to <<_bfd_generic_link_add_one_symbol>>.
183 
184 	The <<_bfd_link_add_symbols>> routine should not use
185 	<<bfd_canonicalize_symtab>> to read the symbols.  The point of
186 	providing this routine is to avoid the overhead of converting
187 	the symbols into generic <<asymbol>> structures.
188 
189 @findex _bfd_generic_link_add_one_symbol
190 	<<_bfd_generic_link_add_one_symbol>> handles the details of
191 	combining common symbols, warning about multiple definitions,
192 	and so forth.  It takes arguments which describe the symbol to
193 	add, notably symbol flags, a section, and an offset.  The
194 	symbol flags include such things as <<BSF_WEAK>> or
195 	<<BSF_INDIRECT>>.  The section is a section in the object
196 	file, or something like <<bfd_und_section_ptr>> for an undefined
197 	symbol or <<bfd_com_section_ptr>> for a common symbol.
198 
199 	If the <<_bfd_final_link>> routine is also going to need to
200 	read the symbol information, the <<_bfd_link_add_symbols>>
201 	routine should save it somewhere attached to the object file
202 	BFD.  However, the information should only be saved if the
203 	<<keep_memory>> field of the <<info>> argument is TRUE, so
204 	that the <<-no-keep-memory>> linker switch is effective.
205 
206 	The a.out function which adds symbols from an object file is
207 	<<aout_link_add_object_symbols>>, and most of the interesting
208 	work is in <<aout_link_add_symbols>>.  The latter saves
209 	pointers to the hash tables entries created by
210 	<<_bfd_generic_link_add_one_symbol>> indexed by symbol number,
211 	so that the <<_bfd_final_link>> routine does not have to call
212 	the hash table lookup routine to locate the entry.
213 
214 INODE
215 Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table
216 SUBSUBSECTION
217 	Adding symbols from an archive
218 
219 	When the <<_bfd_link_add_symbols>> routine is passed an
220 	archive, it must look through the symbols defined by the
221 	archive and decide which elements of the archive should be
222 	included in the link.  For each such element it must call the
223 	<<add_archive_element>> linker callback, and it must add the
224 	symbols from the object file to the linker hash table.  (The
225 	callback may in fact indicate that a replacement BFD should be
226 	used, in which case the symbols from that BFD should be added
227 	to the linker hash table instead.)
228 
229 @findex _bfd_generic_link_add_archive_symbols
230 	In most cases the work of looking through the symbols in the
231 	archive should be done by the
232 	<<_bfd_generic_link_add_archive_symbols>> function.
233 	<<_bfd_generic_link_add_archive_symbols>> is passed a function
234 	to call to make the final decision about adding an archive
235 	element to the link and to do the actual work of adding the
236 	symbols to the linker hash table.  If the element is to
237 	be included, the <<add_archive_element>> linker callback
238 	routine must be called with the element as an argument, and
239 	the element's symbols must be added to the linker hash table
240 	just as though the element had itself been passed to the
241 	<<_bfd_link_add_symbols>> function.
242 
243 	When the a.out <<_bfd_link_add_symbols>> function receives an
244 	archive, it calls <<_bfd_generic_link_add_archive_symbols>>
245 	passing <<aout_link_check_archive_element>> as the function
246 	argument. <<aout_link_check_archive_element>> calls
247 	<<aout_link_check_ar_symbols>>.  If the latter decides to add
248 	the element (an element is only added if it provides a real,
249 	non-common, definition for a previously undefined or common
250 	symbol) it calls the <<add_archive_element>> callback and then
251 	<<aout_link_check_archive_element>> calls
252 	<<aout_link_add_symbols>> to actually add the symbols to the
253 	linker hash table - possibly those of a substitute BFD, if the
254 	<<add_archive_element>> callback avails itself of that option.
255 
256 	The ECOFF back end is unusual in that it does not normally
257 	call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
258 	archives already contain a hash table of symbols.  The ECOFF
259 	back end searches the archive itself to avoid the overhead of
260 	creating a new hash table.
261 
262 INODE
263 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
264 SUBSECTION
265 	Performing the final link
266 
267 @cindex _bfd_link_final_link in target vector
268 @cindex target vector (_bfd_final_link)
269 	When all the input files have been processed, the linker calls
270 	the <<_bfd_final_link>> entry point of the output BFD.  This
271 	routine is responsible for producing the final output file,
272 	which has several aspects.  It must relocate the contents of
273 	the input sections and copy the data into the output sections.
274 	It must build an output symbol table including any local
275 	symbols from the input files and the global symbols from the
276 	hash table.  When producing relocatable output, it must
277 	modify the input relocs and write them into the output file.
278 	There may also be object format dependent work to be done.
279 
280 	The linker will also call the <<write_object_contents>> entry
281 	point when the BFD is closed.  The two entry points must work
282 	together in order to produce the correct output file.
283 
284 	The details of how this works are inevitably dependent upon
285 	the specific object file format.  The a.out
286 	<<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
287 
288 @menu
289 @* Information provided by the linker::
290 @* Relocating the section contents::
291 @* Writing the symbol table::
292 @end menu
293 
294 INODE
295 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
296 SUBSUBSECTION
297 	Information provided by the linker
298 
299 	Before the linker calls the <<_bfd_final_link>> entry point,
300 	it sets up some data structures for the function to use.
301 
302 	The <<input_bfds>> field of the <<bfd_link_info>> structure
303 	will point to a list of all the input files included in the
304 	link.  These files are linked through the <<link.next>> field
305 	of the <<bfd>> structure.
306 
307 	Each section in the output file will have a list of
308 	<<link_order>> structures attached to the <<map_head.link_order>>
309 	field (the <<link_order>> structure is defined in
310 	<<bfdlink.h>>).  These structures describe how to create the
311 	contents of the output section in terms of the contents of
312 	various input sections, fill constants, and, eventually, other
313 	types of information.  They also describe relocs that must be
314 	created by the BFD backend, but do not correspond to any input
315 	file; this is used to support -Ur, which builds constructors
316 	while generating a relocatable object file.
317 
318 INODE
319 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
320 SUBSUBSECTION
321 	Relocating the section contents
322 
323 	The <<_bfd_final_link>> function should look through the
324 	<<link_order>> structures attached to each section of the
325 	output file.  Each <<link_order>> structure should either be
326 	handled specially, or it should be passed to the function
327 	<<_bfd_default_link_order>> which will do the right thing
328 	(<<_bfd_default_link_order>> is defined in <<linker.c>>).
329 
330 	For efficiency, a <<link_order>> of type
331 	<<bfd_indirect_link_order>> whose associated section belongs
332 	to a BFD of the same format as the output BFD must be handled
333 	specially.  This type of <<link_order>> describes part of an
334 	output section in terms of a section belonging to one of the
335 	input files.  The <<_bfd_final_link>> function should read the
336 	contents of the section and any associated relocs, apply the
337 	relocs to the section contents, and write out the modified
338 	section contents.  If performing a relocatable link, the
339 	relocs themselves must also be modified and written out.
340 
341 @findex _bfd_relocate_contents
342 @findex _bfd_final_link_relocate
343 	The functions <<_bfd_relocate_contents>> and
344 	<<_bfd_final_link_relocate>> provide some general support for
345 	performing the actual relocations, notably overflow checking.
346 	Their arguments include information about the symbol the
347 	relocation is against and a <<reloc_howto_type>> argument
348 	which describes the relocation to perform.  These functions
349 	are defined in <<reloc.c>>.
350 
351 	The a.out function which handles reading, relocating, and
352 	writing section contents is <<aout_link_input_section>>.  The
353 	actual relocation is done in <<aout_link_input_section_std>>
354 	and <<aout_link_input_section_ext>>.
355 
356 INODE
357 Writing the symbol table, , Relocating the section contents, Performing the Final Link
358 SUBSUBSECTION
359 	Writing the symbol table
360 
361 	The <<_bfd_final_link>> function must gather all the symbols
362 	in the input files and write them out.  It must also write out
363 	all the symbols in the global hash table.  This must be
364 	controlled by the <<strip>> and <<discard>> fields of the
365 	<<bfd_link_info>> structure.
366 
367 	The local symbols of the input files will not have been
368 	entered into the linker hash table.  The <<_bfd_final_link>>
369 	routine must consider each input file and include the symbols
370 	in the output file.  It may be convenient to do this when
371 	looking through the <<link_order>> structures, or it may be
372 	done by stepping through the <<input_bfds>> list.
373 
374 	The <<_bfd_final_link>> routine must also traverse the global
375 	hash table to gather all the externally visible symbols.  It
376 	is possible that most of the externally visible symbols may be
377 	written out when considering the symbols of each input file,
378 	but it is still necessary to traverse the hash table since the
379 	linker script may have defined some symbols that are not in
380 	any of the input files.
381 
382 	The <<strip>> field of the <<bfd_link_info>> structure
383 	controls which symbols are written out.  The possible values
384 	are listed in <<bfdlink.h>>.  If the value is <<strip_some>>,
385 	then the <<keep_hash>> field of the <<bfd_link_info>>
386 	structure is a hash table of symbols to keep; each symbol
387 	should be looked up in this hash table, and only symbols which
388 	are present should be included in the output file.
389 
390 	If the <<strip>> field of the <<bfd_link_info>> structure
391 	permits local symbols to be written out, the <<discard>> field
392 	is used to further controls which local symbols are included
393 	in the output file.  If the value is <<discard_l>>, then all
394 	local symbols which begin with a certain prefix are discarded;
395 	this is controlled by the <<bfd_is_local_label_name>> entry point.
396 
397 	The a.out backend handles symbols by calling
398 	<<aout_link_write_symbols>> on each input BFD and then
399 	traversing the global hash table with the function
400 	<<aout_link_write_other_symbol>>.  It builds a string table
401 	while writing out the symbols, which is written to the output
402 	file at the end of <<NAME(aout,final_link)>>.
403 */
404 
405 static bfd_boolean generic_link_add_object_symbols
406   (bfd *, struct bfd_link_info *);
407 static bfd_boolean generic_link_check_archive_element
408   (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *, const char *,
409    bfd_boolean *);
410 static bfd_boolean generic_link_add_symbol_list
411   (bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **);
412 static bfd_boolean generic_add_output_symbol
413   (bfd *, size_t *psymalloc, asymbol *);
414 static bfd_boolean default_data_link_order
415   (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *);
416 static bfd_boolean default_indirect_link_order
417   (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *,
418    bfd_boolean);
419 
420 /* The link hash table structure is defined in bfdlink.h.  It provides
421    a base hash table which the backend specific hash tables are built
422    upon.  */
423 
424 /* Routine to create an entry in the link hash table.  */
425 
426 struct bfd_hash_entry *
427 _bfd_link_hash_newfunc (struct bfd_hash_entry *entry,
428 			struct bfd_hash_table *table,
429 			const char *string)
430 {
431   /* Allocate the structure if it has not already been allocated by a
432      subclass.  */
433   if (entry == NULL)
434     {
435       entry = (struct bfd_hash_entry *)
436 	  bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry));
437       if (entry == NULL)
438 	return entry;
439     }
440 
441   /* Call the allocation method of the superclass.  */
442   entry = bfd_hash_newfunc (entry, table, string);
443   if (entry)
444     {
445       struct bfd_link_hash_entry *h = (struct bfd_link_hash_entry *) entry;
446 
447       /* Initialize the local fields.  */
448       memset ((char *) &h->root + sizeof (h->root), 0,
449 	      sizeof (*h) - sizeof (h->root));
450     }
451 
452   return entry;
453 }
454 
455 /* Initialize a link hash table.  The BFD argument is the one
456    responsible for creating this table.  */
457 
458 bfd_boolean
459 _bfd_link_hash_table_init
460   (struct bfd_link_hash_table *table,
461    bfd *abfd ATTRIBUTE_UNUSED,
462    struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
463 				      struct bfd_hash_table *,
464 				      const char *),
465    unsigned int entsize)
466 {
467   bfd_boolean ret;
468 
469   BFD_ASSERT (!abfd->is_linker_output && !abfd->link.hash);
470   table->undefs = NULL;
471   table->undefs_tail = NULL;
472   table->type = bfd_link_generic_hash_table;
473 
474   ret = bfd_hash_table_init (&table->table, newfunc, entsize);
475   if (ret)
476     {
477       /* Arrange for destruction of this hash table on closing ABFD.  */
478       table->hash_table_free = _bfd_generic_link_hash_table_free;
479       abfd->link.hash = table;
480       abfd->is_linker_output = TRUE;
481     }
482   return ret;
483 }
484 
485 /* Look up a symbol in a link hash table.  If follow is TRUE, we
486    follow bfd_link_hash_indirect and bfd_link_hash_warning links to
487    the real symbol.
488 
489 .{* Return TRUE if the symbol described by a linker hash entry H
490 .   is going to be absolute.  Linker-script defined symbols can be
491 .   converted from absolute to section-relative ones late in the
492 .   link.  Use this macro to correctly determine whether the symbol
493 .   will actually end up absolute in output.  *}
494 .#define bfd_is_abs_symbol(H) \
495 .  (((H)->type == bfd_link_hash_defined \
496 .    || (H)->type == bfd_link_hash_defweak) \
497 .   && bfd_is_abs_section ((H)->u.def.section) \
498 .   && !(H)->rel_from_abs)
499 .
500 */
501 
502 struct bfd_link_hash_entry *
503 bfd_link_hash_lookup (struct bfd_link_hash_table *table,
504 		      const char *string,
505 		      bfd_boolean create,
506 		      bfd_boolean copy,
507 		      bfd_boolean follow)
508 {
509   struct bfd_link_hash_entry *ret;
510 
511   if (table == NULL || string == NULL)
512     return NULL;
513 
514   ret = ((struct bfd_link_hash_entry *)
515 	 bfd_hash_lookup (&table->table, string, create, copy));
516 
517   if (follow && ret != NULL)
518     {
519       while (ret->type == bfd_link_hash_indirect
520 	     || ret->type == bfd_link_hash_warning)
521 	ret = ret->u.i.link;
522     }
523 
524   return ret;
525 }
526 
527 /* Look up a symbol in the main linker hash table if the symbol might
528    be wrapped.  This should only be used for references to an
529    undefined symbol, not for definitions of a symbol.  */
530 
531 struct bfd_link_hash_entry *
532 bfd_wrapped_link_hash_lookup (bfd *abfd,
533 			      struct bfd_link_info *info,
534 			      const char *string,
535 			      bfd_boolean create,
536 			      bfd_boolean copy,
537 			      bfd_boolean follow)
538 {
539   bfd_size_type amt;
540 
541   if (info->wrap_hash != NULL)
542     {
543       const char *l;
544       char prefix = '\0';
545 
546       l = string;
547       if (*l == bfd_get_symbol_leading_char (abfd) || *l == info->wrap_char)
548 	{
549 	  prefix = *l;
550 	  ++l;
551 	}
552 
553 #undef WRAP
554 #define WRAP "__wrap_"
555 
556       if (bfd_hash_lookup (info->wrap_hash, l, FALSE, FALSE) != NULL)
557 	{
558 	  char *n;
559 	  struct bfd_link_hash_entry *h;
560 
561 	  /* This symbol is being wrapped.  We want to replace all
562 	     references to SYM with references to __wrap_SYM.  */
563 
564 	  amt = strlen (l) + sizeof WRAP + 1;
565 	  n = (char *) bfd_malloc (amt);
566 	  if (n == NULL)
567 	    return NULL;
568 
569 	  n[0] = prefix;
570 	  n[1] = '\0';
571 	  strcat (n, WRAP);
572 	  strcat (n, l);
573 	  h = bfd_link_hash_lookup (info->hash, n, create, TRUE, follow);
574 	  free (n);
575 	  return h;
576 	}
577 
578 #undef  REAL
579 #define REAL "__real_"
580 
581       if (*l == '_'
582 	  && CONST_STRNEQ (l, REAL)
583 	  && bfd_hash_lookup (info->wrap_hash, l + sizeof REAL - 1,
584 			      FALSE, FALSE) != NULL)
585 	{
586 	  char *n;
587 	  struct bfd_link_hash_entry *h;
588 
589 	  /* This is a reference to __real_SYM, where SYM is being
590 	     wrapped.  We want to replace all references to __real_SYM
591 	     with references to SYM.  */
592 
593 	  amt = strlen (l + sizeof REAL - 1) + 2;
594 	  n = (char *) bfd_malloc (amt);
595 	  if (n == NULL)
596 	    return NULL;
597 
598 	  n[0] = prefix;
599 	  n[1] = '\0';
600 	  strcat (n, l + sizeof REAL - 1);
601 	  h = bfd_link_hash_lookup (info->hash, n, create, TRUE, follow);
602 	  free (n);
603 	  return h;
604 	}
605 
606 #undef REAL
607     }
608 
609   return bfd_link_hash_lookup (info->hash, string, create, copy, follow);
610 }
611 
612 /* If H is a wrapped symbol, ie. the symbol name starts with "__wrap_"
613    and the remainder is found in wrap_hash, return the real symbol.  */
614 
615 struct bfd_link_hash_entry *
616 unwrap_hash_lookup (struct bfd_link_info *info,
617 		    bfd *input_bfd,
618 		    struct bfd_link_hash_entry *h)
619 {
620   const char *l = h->root.string;
621 
622   if (*l == bfd_get_symbol_leading_char (input_bfd)
623       || *l == info->wrap_char)
624     ++l;
625 
626   if (CONST_STRNEQ (l, WRAP))
627     {
628       l += sizeof WRAP - 1;
629 
630       if (bfd_hash_lookup (info->wrap_hash, l, FALSE, FALSE) != NULL)
631 	{
632 	  char save = 0;
633 	  if (l - (sizeof WRAP - 1) != h->root.string)
634 	    {
635 	      --l;
636 	      save = *l;
637 	      *(char *) l = *h->root.string;
638 	    }
639 	  h = bfd_link_hash_lookup (info->hash, l, FALSE, FALSE, FALSE);
640 	  if (save)
641 	    *(char *) l = save;
642 	}
643     }
644   return h;
645 }
646 #undef WRAP
647 
648 /* Traverse a generic link hash table.  Differs from bfd_hash_traverse
649    in the treatment of warning symbols.  When warning symbols are
650    created they replace the real symbol, so you don't get to see the
651    real symbol in a bfd_hash_traverse.  This traversal calls func with
652    the real symbol.  */
653 
654 void
655 bfd_link_hash_traverse
656   (struct bfd_link_hash_table *htab,
657    bfd_boolean (*func) (struct bfd_link_hash_entry *, void *),
658    void *info)
659 {
660   unsigned int i;
661 
662   htab->table.frozen = 1;
663   for (i = 0; i < htab->table.size; i++)
664     {
665       struct bfd_link_hash_entry *p;
666 
667       p = (struct bfd_link_hash_entry *) htab->table.table[i];
668       for (; p != NULL; p = (struct bfd_link_hash_entry *) p->root.next)
669 	if (!(*func) (p->type == bfd_link_hash_warning ? p->u.i.link : p, info))
670 	  goto out;
671     }
672  out:
673   htab->table.frozen = 0;
674 }
675 
676 /* Add a symbol to the linker hash table undefs list.  */
677 
678 void
679 bfd_link_add_undef (struct bfd_link_hash_table *table,
680 		    struct bfd_link_hash_entry *h)
681 {
682   BFD_ASSERT (h->u.undef.next == NULL);
683   if (table->undefs_tail != NULL)
684     table->undefs_tail->u.undef.next = h;
685   if (table->undefs == NULL)
686     table->undefs = h;
687   table->undefs_tail = h;
688 }
689 
690 /* The undefs list was designed so that in normal use we don't need to
691    remove entries.  However, if symbols on the list are changed from
692    bfd_link_hash_undefined to either bfd_link_hash_undefweak or
693    bfd_link_hash_new for some reason, then they must be removed from the
694    list.  Failure to do so might result in the linker attempting to add
695    the symbol to the list again at a later stage.  */
696 
697 void
698 bfd_link_repair_undef_list (struct bfd_link_hash_table *table)
699 {
700   struct bfd_link_hash_entry **pun;
701 
702   pun = &table->undefs;
703   while (*pun != NULL)
704     {
705       struct bfd_link_hash_entry *h = *pun;
706 
707       if (h->type == bfd_link_hash_new
708 	  || h->type == bfd_link_hash_undefweak)
709 	{
710 	  *pun = h->u.undef.next;
711 	  h->u.undef.next = NULL;
712 	  if (h == table->undefs_tail)
713 	    {
714 	      if (pun == &table->undefs)
715 		table->undefs_tail = NULL;
716 	      else
717 		/* pun points at an u.undef.next field.  Go back to
718 		   the start of the link_hash_entry.  */
719 		table->undefs_tail = (struct bfd_link_hash_entry *)
720 		  ((char *) pun - ((char *) &h->u.undef.next - (char *) h));
721 	      break;
722 	    }
723 	}
724       else
725 	pun = &h->u.undef.next;
726     }
727 }
728 
729 /* Routine to create an entry in a generic link hash table.  */
730 
731 struct bfd_hash_entry *
732 _bfd_generic_link_hash_newfunc (struct bfd_hash_entry *entry,
733 				struct bfd_hash_table *table,
734 				const char *string)
735 {
736   /* Allocate the structure if it has not already been allocated by a
737      subclass.  */
738   if (entry == NULL)
739     {
740       entry = (struct bfd_hash_entry *)
741 	bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry));
742       if (entry == NULL)
743 	return entry;
744     }
745 
746   /* Call the allocation method of the superclass.  */
747   entry = _bfd_link_hash_newfunc (entry, table, string);
748   if (entry)
749     {
750       struct generic_link_hash_entry *ret;
751 
752       /* Set local fields.  */
753       ret = (struct generic_link_hash_entry *) entry;
754       ret->written = FALSE;
755       ret->sym = NULL;
756     }
757 
758   return entry;
759 }
760 
761 /* Create a generic link hash table.  */
762 
763 struct bfd_link_hash_table *
764 _bfd_generic_link_hash_table_create (bfd *abfd)
765 {
766   struct generic_link_hash_table *ret;
767   bfd_size_type amt = sizeof (struct generic_link_hash_table);
768 
769   ret = (struct generic_link_hash_table *) bfd_malloc (amt);
770   if (ret == NULL)
771     return NULL;
772   if (! _bfd_link_hash_table_init (&ret->root, abfd,
773 				   _bfd_generic_link_hash_newfunc,
774 				   sizeof (struct generic_link_hash_entry)))
775     {
776       free (ret);
777       return NULL;
778     }
779   return &ret->root;
780 }
781 
782 void
783 _bfd_generic_link_hash_table_free (bfd *obfd)
784 {
785   struct generic_link_hash_table *ret;
786 
787   BFD_ASSERT (obfd->is_linker_output && obfd->link.hash);
788   ret = (struct generic_link_hash_table *) obfd->link.hash;
789   bfd_hash_table_free (&ret->root.table);
790   free (ret);
791   obfd->link.hash = NULL;
792   obfd->is_linker_output = FALSE;
793 }
794 
795 /* Grab the symbols for an object file when doing a generic link.  We
796    store the symbols in the outsymbols field.  We need to keep them
797    around for the entire link to ensure that we only read them once.
798    If we read them multiple times, we might wind up with relocs and
799    the hash table pointing to different instances of the symbol
800    structure.  */
801 
802 bfd_boolean
803 bfd_generic_link_read_symbols (bfd *abfd)
804 {
805   if (bfd_get_outsymbols (abfd) == NULL)
806     {
807       long symsize;
808       long symcount;
809 
810       symsize = bfd_get_symtab_upper_bound (abfd);
811       if (symsize < 0)
812 	return FALSE;
813       bfd_get_outsymbols (abfd) = (struct bfd_symbol **) bfd_alloc (abfd,
814 								    symsize);
815       if (bfd_get_outsymbols (abfd) == NULL && symsize != 0)
816 	return FALSE;
817       symcount = bfd_canonicalize_symtab (abfd, bfd_get_outsymbols (abfd));
818       if (symcount < 0)
819 	return FALSE;
820       bfd_get_symcount (abfd) = symcount;
821     }
822 
823   return TRUE;
824 }
825 
826 /* Indicate that we are only retrieving symbol values from this
827    section.  We want the symbols to act as though the values in the
828    file are absolute.  */
829 
830 void
831 _bfd_generic_link_just_syms (asection *sec,
832 			     struct bfd_link_info *info ATTRIBUTE_UNUSED)
833 {
834   sec->sec_info_type = SEC_INFO_TYPE_JUST_SYMS;
835   sec->output_section = bfd_abs_section_ptr;
836   sec->output_offset = sec->vma;
837 }
838 
839 /* Copy the symbol type and other attributes for a linker script
840    assignment from HSRC to HDEST.
841    The default implementation does nothing.  */
842 void
843 _bfd_generic_copy_link_hash_symbol_type (bfd *abfd ATTRIBUTE_UNUSED,
844     struct bfd_link_hash_entry *hdest ATTRIBUTE_UNUSED,
845     struct bfd_link_hash_entry *hsrc ATTRIBUTE_UNUSED)
846 {
847 }
848 
849 /* Generic function to add symbols from an object file to the
850    global hash table.  */
851 
852 bfd_boolean
853 _bfd_generic_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
854 {
855   bfd_boolean ret;
856 
857   switch (bfd_get_format (abfd))
858     {
859     case bfd_object:
860       ret = generic_link_add_object_symbols (abfd, info);
861       break;
862     case bfd_archive:
863       ret = (_bfd_generic_link_add_archive_symbols
864 	     (abfd, info, generic_link_check_archive_element));
865       break;
866     default:
867       bfd_set_error (bfd_error_wrong_format);
868       ret = FALSE;
869     }
870 
871   return ret;
872 }
873 
874 /* Add symbols from an object file to the global hash table.  */
875 
876 static bfd_boolean
877 generic_link_add_object_symbols (bfd *abfd,
878 				 struct bfd_link_info *info)
879 {
880   bfd_size_type symcount;
881   struct bfd_symbol **outsyms;
882 
883   if (!bfd_generic_link_read_symbols (abfd))
884     return FALSE;
885   symcount = _bfd_generic_link_get_symcount (abfd);
886   outsyms = _bfd_generic_link_get_symbols (abfd);
887   return generic_link_add_symbol_list (abfd, info, symcount, outsyms);
888 }
889 
890 /* Generic function to add symbols from an archive file to the global
891    hash file.  This function presumes that the archive symbol table
892    has already been read in (this is normally done by the
893    bfd_check_format entry point).  It looks through the archive symbol
894    table for symbols that are undefined or common in the linker global
895    symbol hash table.  When one is found, the CHECKFN argument is used
896    to see if an object file should be included.  This allows targets
897    to customize common symbol behaviour.  CHECKFN should set *PNEEDED
898    to TRUE if the object file should be included, and must also call
899    the bfd_link_info add_archive_element callback function and handle
900    adding the symbols to the global hash table.  CHECKFN must notice
901    if the callback indicates a substitute BFD, and arrange to add
902    those symbols instead if it does so.  CHECKFN should only return
903    FALSE if some sort of error occurs.  */
904 
905 bfd_boolean
906 _bfd_generic_link_add_archive_symbols
907   (bfd *abfd,
908    struct bfd_link_info *info,
909    bfd_boolean (*checkfn) (bfd *, struct bfd_link_info *,
910 			   struct bfd_link_hash_entry *, const char *,
911 			   bfd_boolean *))
912 {
913   bfd_boolean loop;
914   bfd_size_type amt;
915   unsigned char *included;
916 
917   if (! bfd_has_map (abfd))
918     {
919       /* An empty archive is a special case.  */
920       if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
921 	return TRUE;
922       bfd_set_error (bfd_error_no_armap);
923       return FALSE;
924     }
925 
926   amt = bfd_ardata (abfd)->symdef_count;
927   if (amt == 0)
928     return TRUE;
929   amt *= sizeof (*included);
930   included = (unsigned char *) bfd_zmalloc (amt);
931   if (included == NULL)
932     return FALSE;
933 
934   do
935     {
936       carsym *arsyms;
937       carsym *arsym_end;
938       carsym *arsym;
939       unsigned int indx;
940       file_ptr last_ar_offset = -1;
941       bfd_boolean needed = FALSE;
942       bfd *element = NULL;
943 
944       loop = FALSE;
945       arsyms = bfd_ardata (abfd)->symdefs;
946       arsym_end = arsyms + bfd_ardata (abfd)->symdef_count;
947       for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++)
948 	{
949 	  struct bfd_link_hash_entry *h;
950 	  struct bfd_link_hash_entry *undefs_tail;
951 
952 	  if (included[indx])
953 	    continue;
954 	  if (needed && arsym->file_offset == last_ar_offset)
955 	    {
956 	      included[indx] = 1;
957 	      continue;
958 	    }
959 
960 	  if (arsym->name == NULL)
961 	    goto error_return;
962 
963 	  h = bfd_link_hash_lookup (info->hash, arsym->name,
964 				    FALSE, FALSE, TRUE);
965 
966 	  if (h == NULL
967 	      && info->pei386_auto_import
968 	      && CONST_STRNEQ (arsym->name, "__imp_"))
969 	    h = bfd_link_hash_lookup (info->hash, arsym->name + 6,
970 				      FALSE, FALSE, TRUE);
971 	  if (h == NULL)
972 	    continue;
973 
974 	  if (h->type != bfd_link_hash_undefined
975 	      && h->type != bfd_link_hash_common)
976 	    {
977 	      if (h->type != bfd_link_hash_undefweak)
978 		/* Symbol must be defined.  Don't check it again.  */
979 		included[indx] = 1;
980 	      continue;
981 	    }
982 
983 	  if (last_ar_offset != arsym->file_offset)
984 	    {
985 	      last_ar_offset = arsym->file_offset;
986 	      element = _bfd_get_elt_at_filepos (abfd, last_ar_offset);
987 	      if (element == NULL
988 		  || !bfd_check_format (element, bfd_object))
989 		goto error_return;
990 	    }
991 
992 	  undefs_tail = info->hash->undefs_tail;
993 
994 	  /* CHECKFN will see if this element should be included, and
995 	     go ahead and include it if appropriate.  */
996 	  if (! (*checkfn) (element, info, h, arsym->name, &needed))
997 	    goto error_return;
998 
999 	  if (needed)
1000 	    {
1001 	      unsigned int mark;
1002 
1003 	      /* Look backward to mark all symbols from this object file
1004 		 which we have already seen in this pass.  */
1005 	      mark = indx;
1006 	      do
1007 		{
1008 		  included[mark] = 1;
1009 		  if (mark == 0)
1010 		    break;
1011 		  --mark;
1012 		}
1013 	      while (arsyms[mark].file_offset == last_ar_offset);
1014 
1015 	      if (undefs_tail != info->hash->undefs_tail)
1016 		loop = TRUE;
1017 	    }
1018 	}
1019     } while (loop);
1020 
1021   free (included);
1022   return TRUE;
1023 
1024  error_return:
1025   free (included);
1026   return FALSE;
1027 }
1028 
1029 /* See if we should include an archive element.  */
1030 
1031 static bfd_boolean
1032 generic_link_check_archive_element (bfd *abfd,
1033 				    struct bfd_link_info *info,
1034 				    struct bfd_link_hash_entry *h,
1035 				    const char *name ATTRIBUTE_UNUSED,
1036 				    bfd_boolean *pneeded)
1037 {
1038   asymbol **pp, **ppend;
1039 
1040   *pneeded = FALSE;
1041 
1042   if (!bfd_generic_link_read_symbols (abfd))
1043     return FALSE;
1044 
1045   pp = _bfd_generic_link_get_symbols (abfd);
1046   ppend = pp + _bfd_generic_link_get_symcount (abfd);
1047   for (; pp < ppend; pp++)
1048     {
1049       asymbol *p;
1050 
1051       p = *pp;
1052 
1053       /* We are only interested in globally visible symbols.  */
1054       if (! bfd_is_com_section (p->section)
1055 	  && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0)
1056 	continue;
1057 
1058       /* We are only interested if we know something about this
1059 	 symbol, and it is undefined or common.  An undefined weak
1060 	 symbol (type bfd_link_hash_undefweak) is not considered to be
1061 	 a reference when pulling files out of an archive.  See the
1062 	 SVR4 ABI, p. 4-27.  */
1063       h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), FALSE,
1064 				FALSE, TRUE);
1065       if (h == NULL
1066 	  || (h->type != bfd_link_hash_undefined
1067 	      && h->type != bfd_link_hash_common))
1068 	continue;
1069 
1070       /* P is a symbol we are looking for.  */
1071 
1072       if (! bfd_is_com_section (p->section)
1073 	  || (h->type == bfd_link_hash_undefined
1074 	      && h->u.undef.abfd == NULL))
1075 	{
1076 	  /* P is not a common symbol, or an undefined reference was
1077 	     created from outside BFD such as from a linker -u option.
1078 	     This object file defines the symbol, so pull it in.  */
1079 	  *pneeded = TRUE;
1080 	  if (!(*info->callbacks
1081 		->add_archive_element) (info, abfd, bfd_asymbol_name (p),
1082 					&abfd))
1083 	    return FALSE;
1084 	  /* Potentially, the add_archive_element hook may have set a
1085 	     substitute BFD for us.  */
1086 	  return bfd_link_add_symbols (abfd, info);
1087 	}
1088 
1089       /* P is a common symbol.  */
1090 
1091       if (h->type == bfd_link_hash_undefined)
1092 	{
1093 	  bfd *symbfd;
1094 	  bfd_vma size;
1095 	  unsigned int power;
1096 
1097 	  /* Turn the symbol into a common symbol but do not link in
1098 	     the object file.  This is how a.out works.  Object
1099 	     formats that require different semantics must implement
1100 	     this function differently.  This symbol is already on the
1101 	     undefs list.  We add the section to a common section
1102 	     attached to symbfd to ensure that it is in a BFD which
1103 	     will be linked in.  */
1104 	  symbfd = h->u.undef.abfd;
1105 	  h->type = bfd_link_hash_common;
1106 	  h->u.c.p = (struct bfd_link_hash_common_entry *)
1107 	    bfd_hash_allocate (&info->hash->table,
1108 			       sizeof (struct bfd_link_hash_common_entry));
1109 	  if (h->u.c.p == NULL)
1110 	    return FALSE;
1111 
1112 	  size = bfd_asymbol_value (p);
1113 	  h->u.c.size = size;
1114 
1115 	  power = bfd_log2 (size);
1116 	  if (power > 4)
1117 	    power = 4;
1118 	  h->u.c.p->alignment_power = power;
1119 
1120 	  if (p->section == bfd_com_section_ptr)
1121 	    h->u.c.p->section = bfd_make_section_old_way (symbfd, "COMMON");
1122 	  else
1123 	    h->u.c.p->section = bfd_make_section_old_way (symbfd,
1124 							  p->section->name);
1125 	  h->u.c.p->section->flags |= SEC_ALLOC;
1126 	}
1127       else
1128 	{
1129 	  /* Adjust the size of the common symbol if necessary.  This
1130 	     is how a.out works.  Object formats that require
1131 	     different semantics must implement this function
1132 	     differently.  */
1133 	  if (bfd_asymbol_value (p) > h->u.c.size)
1134 	    h->u.c.size = bfd_asymbol_value (p);
1135 	}
1136     }
1137 
1138   /* This archive element is not needed.  */
1139   return TRUE;
1140 }
1141 
1142 /* Add the symbols from an object file to the global hash table.  ABFD
1143    is the object file.  INFO is the linker information.  SYMBOL_COUNT
1144    is the number of symbols.  SYMBOLS is the list of symbols.  */
1145 
1146 static bfd_boolean
1147 generic_link_add_symbol_list (bfd *abfd,
1148 			      struct bfd_link_info *info,
1149 			      bfd_size_type symbol_count,
1150 			      asymbol **symbols)
1151 {
1152   asymbol **pp, **ppend;
1153 
1154   pp = symbols;
1155   ppend = symbols + symbol_count;
1156   for (; pp < ppend; pp++)
1157     {
1158       asymbol *p;
1159 
1160       p = *pp;
1161 
1162       if ((p->flags & (BSF_INDIRECT
1163 		       | BSF_WARNING
1164 		       | BSF_GLOBAL
1165 		       | BSF_CONSTRUCTOR
1166 		       | BSF_WEAK)) != 0
1167 	  || bfd_is_und_section (bfd_get_section (p))
1168 	  || bfd_is_com_section (bfd_get_section (p))
1169 	  || bfd_is_ind_section (bfd_get_section (p)))
1170 	{
1171 	  const char *name;
1172 	  const char *string;
1173 	  struct generic_link_hash_entry *h;
1174 	  struct bfd_link_hash_entry *bh;
1175 
1176 	  string = name = bfd_asymbol_name (p);
1177 	  if (((p->flags & BSF_INDIRECT) != 0
1178 	       || bfd_is_ind_section (p->section))
1179 	      && pp + 1 < ppend)
1180 	    {
1181 	      pp++;
1182 	      string = bfd_asymbol_name (*pp);
1183 	    }
1184 	  else if ((p->flags & BSF_WARNING) != 0
1185 		   && pp + 1 < ppend)
1186 	    {
1187 	      /* The name of P is actually the warning string, and the
1188 		 next symbol is the one to warn about.  */
1189 	      pp++;
1190 	      name = bfd_asymbol_name (*pp);
1191 	    }
1192 
1193 	  bh = NULL;
1194 	  if (! (_bfd_generic_link_add_one_symbol
1195 		 (info, abfd, name, p->flags, bfd_get_section (p),
1196 		  p->value, string, FALSE, FALSE, &bh)))
1197 	    return FALSE;
1198 	  h = (struct generic_link_hash_entry *) bh;
1199 
1200 	  /* If this is a constructor symbol, and the linker didn't do
1201 	     anything with it, then we want to just pass the symbol
1202 	     through to the output file.  This will happen when
1203 	     linking with -r.  */
1204 	  if ((p->flags & BSF_CONSTRUCTOR) != 0
1205 	      && (h == NULL || h->root.type == bfd_link_hash_new))
1206 	    {
1207 	      p->udata.p = NULL;
1208 	      continue;
1209 	    }
1210 
1211 	  /* Save the BFD symbol so that we don't lose any backend
1212 	     specific information that may be attached to it.  We only
1213 	     want this one if it gives more information than the
1214 	     existing one; we don't want to replace a defined symbol
1215 	     with an undefined one.  This routine may be called with a
1216 	     hash table other than the generic hash table, so we only
1217 	     do this if we are certain that the hash table is a
1218 	     generic one.  */
1219 	  if (info->output_bfd->xvec == abfd->xvec)
1220 	    {
1221 	      if (h->sym == NULL
1222 		  || (! bfd_is_und_section (bfd_get_section (p))
1223 		      && (! bfd_is_com_section (bfd_get_section (p))
1224 			  || bfd_is_und_section (bfd_get_section (h->sym)))))
1225 		{
1226 		  h->sym = p;
1227 		  /* BSF_OLD_COMMON is a hack to support COFF reloc
1228 		     reading, and it should go away when the COFF
1229 		     linker is switched to the new version.  */
1230 		  if (bfd_is_com_section (bfd_get_section (p)))
1231 		    p->flags |= BSF_OLD_COMMON;
1232 		}
1233 	    }
1234 
1235 	  /* Store a back pointer from the symbol to the hash
1236 	     table entry for the benefit of relaxation code until
1237 	     it gets rewritten to not use asymbol structures.
1238 	     Setting this is also used to check whether these
1239 	     symbols were set up by the generic linker.  */
1240 	  p->udata.p = h;
1241 	}
1242     }
1243 
1244   return TRUE;
1245 }
1246 
1247 /* We use a state table to deal with adding symbols from an object
1248    file.  The first index into the state table describes the symbol
1249    from the object file.  The second index into the state table is the
1250    type of the symbol in the hash table.  */
1251 
1252 /* The symbol from the object file is turned into one of these row
1253    values.  */
1254 
1255 enum link_row
1256 {
1257   UNDEF_ROW,		/* Undefined.  */
1258   UNDEFW_ROW,		/* Weak undefined.  */
1259   DEF_ROW,		/* Defined.  */
1260   DEFW_ROW,		/* Weak defined.  */
1261   COMMON_ROW,		/* Common.  */
1262   INDR_ROW,		/* Indirect.  */
1263   WARN_ROW,		/* Warning.  */
1264   SET_ROW		/* Member of set.  */
1265 };
1266 
1267 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1268 #undef FAIL
1269 
1270 /* The actions to take in the state table.  */
1271 
1272 enum link_action
1273 {
1274   FAIL,		/* Abort.  */
1275   UND,		/* Mark symbol undefined.  */
1276   WEAK,		/* Mark symbol weak undefined.  */
1277   DEF,		/* Mark symbol defined.  */
1278   DEFW,		/* Mark symbol weak defined.  */
1279   COM,		/* Mark symbol common.  */
1280   REF,		/* Mark defined symbol referenced.  */
1281   CREF,		/* Possibly warn about common reference to defined symbol.  */
1282   CDEF,		/* Define existing common symbol.  */
1283   NOACT,	/* No action.  */
1284   BIG,		/* Mark symbol common using largest size.  */
1285   MDEF,		/* Multiple definition error.  */
1286   MIND,		/* Multiple indirect symbols.  */
1287   IND,		/* Make indirect symbol.  */
1288   CIND,		/* Make indirect symbol from existing common symbol.  */
1289   SET,		/* Add value to set.  */
1290   MWARN,	/* Make warning symbol.  */
1291   WARN,		/* Warn if referenced, else MWARN.  */
1292   CYCLE,	/* Repeat with symbol pointed to.  */
1293   REFC,		/* Mark indirect symbol referenced and then CYCLE.  */
1294   WARNC		/* Issue warning and then CYCLE.  */
1295 };
1296 
1297 /* The state table itself.  The first index is a link_row and the
1298    second index is a bfd_link_hash_type.  */
1299 
1300 static const enum link_action link_action[8][8] =
1301 {
1302   /* current\prev    new    undef  undefw def    defw   com    indr   warn  */
1303   /* UNDEF_ROW	*/  {UND,   NOACT, UND,   REF,   REF,   NOACT, REFC,  WARNC },
1304   /* UNDEFW_ROW	*/  {WEAK,  NOACT, NOACT, REF,   REF,   NOACT, REFC,  WARNC },
1305   /* DEF_ROW	*/  {DEF,   DEF,   DEF,   MDEF,  DEF,   CDEF,  MDEF,  CYCLE },
1306   /* DEFW_ROW	*/  {DEFW,  DEFW,  DEFW,  NOACT, NOACT, NOACT, NOACT, CYCLE },
1307   /* COMMON_ROW	*/  {COM,   COM,   COM,   CREF,  COM,   BIG,   REFC,  WARNC },
1308   /* INDR_ROW	*/  {IND,   IND,   IND,   MDEF,  IND,   CIND,  MIND,  CYCLE },
1309   /* WARN_ROW   */  {MWARN, WARN,  WARN,  WARN,  WARN,  WARN,  WARN,  NOACT },
1310   /* SET_ROW	*/  {SET,   SET,   SET,   SET,   SET,   SET,   CYCLE, CYCLE }
1311 };
1312 
1313 /* Most of the entries in the LINK_ACTION table are straightforward,
1314    but a few are somewhat subtle.
1315 
1316    A reference to an indirect symbol (UNDEF_ROW/indr or
1317    UNDEFW_ROW/indr) is counted as a reference both to the indirect
1318    symbol and to the symbol the indirect symbol points to.
1319 
1320    A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1321    causes the warning to be issued.
1322 
1323    A common definition of an indirect symbol (COMMON_ROW/indr) is
1324    treated as a multiple definition error.  Likewise for an indirect
1325    definition of a common symbol (INDR_ROW/com).
1326 
1327    An indirect definition of a warning (INDR_ROW/warn) does not cause
1328    the warning to be issued.
1329 
1330    If a warning is created for an indirect symbol (WARN_ROW/indr) no
1331    warning is created for the symbol the indirect symbol points to.
1332 
1333    Adding an entry to a set does not count as a reference to a set,
1334    and no warning is issued (SET_ROW/warn).  */
1335 
1336 /* Return the BFD in which a hash entry has been defined, if known.  */
1337 
1338 static bfd *
1339 hash_entry_bfd (struct bfd_link_hash_entry *h)
1340 {
1341   while (h->type == bfd_link_hash_warning)
1342     h = h->u.i.link;
1343   switch (h->type)
1344     {
1345     default:
1346       return NULL;
1347     case bfd_link_hash_undefined:
1348     case bfd_link_hash_undefweak:
1349       return h->u.undef.abfd;
1350     case bfd_link_hash_defined:
1351     case bfd_link_hash_defweak:
1352       return h->u.def.section->owner;
1353     case bfd_link_hash_common:
1354       return h->u.c.p->section->owner;
1355     }
1356   /*NOTREACHED*/
1357 }
1358 
1359 /* Add a symbol to the global hash table.
1360    ABFD is the BFD the symbol comes from.
1361    NAME is the name of the symbol.
1362    FLAGS is the BSF_* bits associated with the symbol.
1363    SECTION is the section in which the symbol is defined; this may be
1364      bfd_und_section_ptr or bfd_com_section_ptr.
1365    VALUE is the value of the symbol, relative to the section.
1366    STRING is used for either an indirect symbol, in which case it is
1367      the name of the symbol to indirect to, or a warning symbol, in
1368      which case it is the warning string.
1369    COPY is TRUE if NAME or STRING must be copied into locally
1370      allocated memory if they need to be saved.
1371    COLLECT is TRUE if we should automatically collect gcc constructor
1372      or destructor names as collect2 does.
1373    HASHP, if not NULL, is a place to store the created hash table
1374      entry; if *HASHP is not NULL, the caller has already looked up
1375      the hash table entry, and stored it in *HASHP.  */
1376 
1377 bfd_boolean
1378 _bfd_generic_link_add_one_symbol (struct bfd_link_info *info,
1379 				  bfd *abfd,
1380 				  const char *name,
1381 				  flagword flags,
1382 				  asection *section,
1383 				  bfd_vma value,
1384 				  const char *string,
1385 				  bfd_boolean copy,
1386 				  bfd_boolean collect,
1387 				  struct bfd_link_hash_entry **hashp)
1388 {
1389   enum link_row row;
1390   struct bfd_link_hash_entry *h;
1391   struct bfd_link_hash_entry *inh = NULL;
1392   bfd_boolean cycle;
1393 
1394   BFD_ASSERT (section != NULL);
1395 
1396   if (bfd_is_ind_section (section)
1397       || (flags & BSF_INDIRECT) != 0)
1398     {
1399       row = INDR_ROW;
1400       /* Create the indirect symbol here.  This is for the benefit of
1401 	 the plugin "notice" function.
1402 	 STRING is the name of the symbol we want to indirect to.  */
1403       inh = bfd_wrapped_link_hash_lookup (abfd, info, string, TRUE,
1404 					  copy, FALSE);
1405       if (inh == NULL)
1406 	return FALSE;
1407     }
1408   else if ((flags & BSF_WARNING) != 0)
1409     row = WARN_ROW;
1410   else if ((flags & BSF_CONSTRUCTOR) != 0)
1411     row = SET_ROW;
1412   else if (bfd_is_und_section (section))
1413     {
1414       if ((flags & BSF_WEAK) != 0)
1415 	row = UNDEFW_ROW;
1416       else
1417 	row = UNDEF_ROW;
1418     }
1419   else if ((flags & BSF_WEAK) != 0)
1420     row = DEFW_ROW;
1421   else if (bfd_is_com_section (section))
1422     {
1423       row = COMMON_ROW;
1424       if (!bfd_link_relocatable (info)
1425 	  && name[0] == '_'
1426 	  && name[1] == '_'
1427 	  && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0)
1428 	_bfd_error_handler
1429 	  (_("%pB: plugin needed to handle lto object"), abfd);
1430     }
1431   else
1432     row = DEF_ROW;
1433 
1434   if (hashp != NULL && *hashp != NULL)
1435     h = *hashp;
1436   else
1437     {
1438       if (row == UNDEF_ROW || row == UNDEFW_ROW)
1439 	h = bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, copy, FALSE);
1440       else
1441 	h = bfd_link_hash_lookup (info->hash, name, TRUE, copy, FALSE);
1442       if (h == NULL)
1443 	{
1444 	  if (hashp != NULL)
1445 	    *hashp = NULL;
1446 	  return FALSE;
1447 	}
1448     }
1449 
1450   if (info->notice_all
1451       || (info->notice_hash != NULL
1452 	  && bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL))
1453     {
1454       if (! (*info->callbacks->notice) (info, h, inh,
1455 					abfd, section, value, flags))
1456 	return FALSE;
1457     }
1458 
1459   if (hashp != NULL)
1460     *hashp = h;
1461 
1462   do
1463     {
1464       enum link_action action;
1465       int prev;
1466 
1467       prev = h->type;
1468       /* Treat symbols defined by early linker script pass as undefined.  */
1469       if (h->ldscript_def)
1470 	prev = bfd_link_hash_undefined;
1471       cycle = FALSE;
1472       action = link_action[(int) row][prev];
1473       switch (action)
1474 	{
1475 	case FAIL:
1476 	  abort ();
1477 
1478 	case NOACT:
1479 	  /* Do nothing.  */
1480 	  break;
1481 
1482 	case UND:
1483 	  /* Make a new undefined symbol.  */
1484 	  h->type = bfd_link_hash_undefined;
1485 	  h->u.undef.abfd = abfd;
1486 	  bfd_link_add_undef (info->hash, h);
1487 	  break;
1488 
1489 	case WEAK:
1490 	  /* Make a new weak undefined symbol.  */
1491 	  h->type = bfd_link_hash_undefweak;
1492 	  h->u.undef.abfd = abfd;
1493 	  break;
1494 
1495 	case CDEF:
1496 	  /* We have found a definition for a symbol which was
1497 	     previously common.  */
1498 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1499 	  (*info->callbacks->multiple_common) (info, h, abfd,
1500 					       bfd_link_hash_defined, 0);
1501 	  /* Fall through.  */
1502 	case DEF:
1503 	case DEFW:
1504 	  {
1505 	    enum bfd_link_hash_type oldtype;
1506 
1507 	    /* Define a symbol.  */
1508 	    oldtype = h->type;
1509 	    if (action == DEFW)
1510 	      h->type = bfd_link_hash_defweak;
1511 	    else
1512 	      h->type = bfd_link_hash_defined;
1513 	    h->u.def.section = section;
1514 	    h->u.def.value = value;
1515 	    h->linker_def = 0;
1516 	    h->ldscript_def = 0;
1517 
1518 	    /* If we have been asked to, we act like collect2 and
1519 	       identify all functions that might be global
1520 	       constructors and destructors and pass them up in a
1521 	       callback.  We only do this for certain object file
1522 	       types, since many object file types can handle this
1523 	       automatically.  */
1524 	    if (collect && name[0] == '_')
1525 	      {
1526 		const char *s;
1527 
1528 		/* A constructor or destructor name starts like this:
1529 		   _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1530 		   the second are the same character (we accept any
1531 		   character there, in case a new object file format
1532 		   comes along with even worse naming restrictions).  */
1533 
1534 #define CONS_PREFIX "GLOBAL_"
1535 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1536 
1537 		s = name + 1;
1538 		while (*s == '_')
1539 		  ++s;
1540 		if (s[0] == 'G' && CONST_STRNEQ (s, CONS_PREFIX))
1541 		  {
1542 		    char c;
1543 
1544 		    c = s[CONS_PREFIX_LEN + 1];
1545 		    if ((c == 'I' || c == 'D')
1546 			&& s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2])
1547 		      {
1548 			/* If this is a definition of a symbol which
1549 			   was previously weakly defined, we are in
1550 			   trouble.  We have already added a
1551 			   constructor entry for the weak defined
1552 			   symbol, and now we are trying to add one
1553 			   for the new symbol.  Fortunately, this case
1554 			   should never arise in practice.  */
1555 			if (oldtype == bfd_link_hash_defweak)
1556 			  abort ();
1557 
1558 			(*info->callbacks->constructor) (info, c == 'I',
1559 							 h->root.string, abfd,
1560 							 section, value);
1561 		      }
1562 		  }
1563 	      }
1564 	  }
1565 
1566 	  break;
1567 
1568 	case COM:
1569 	  /* We have found a common definition for a symbol.  */
1570 	  if (h->type == bfd_link_hash_new)
1571 	    bfd_link_add_undef (info->hash, h);
1572 	  h->type = bfd_link_hash_common;
1573 	  h->u.c.p = (struct bfd_link_hash_common_entry *)
1574 	    bfd_hash_allocate (&info->hash->table,
1575 			       sizeof (struct bfd_link_hash_common_entry));
1576 	  if (h->u.c.p == NULL)
1577 	    return FALSE;
1578 
1579 	  h->u.c.size = value;
1580 
1581 	  /* Select a default alignment based on the size.  This may
1582 	     be overridden by the caller.  */
1583 	  {
1584 	    unsigned int power;
1585 
1586 	    power = bfd_log2 (value);
1587 	    if (power > 4)
1588 	      power = 4;
1589 	    h->u.c.p->alignment_power = power;
1590 	  }
1591 
1592 	  /* The section of a common symbol is only used if the common
1593 	     symbol is actually allocated.  It basically provides a
1594 	     hook for the linker script to decide which output section
1595 	     the common symbols should be put in.  In most cases, the
1596 	     section of a common symbol will be bfd_com_section_ptr,
1597 	     the code here will choose a common symbol section named
1598 	     "COMMON", and the linker script will contain *(COMMON) in
1599 	     the appropriate place.  A few targets use separate common
1600 	     sections for small symbols, and they require special
1601 	     handling.  */
1602 	  if (section == bfd_com_section_ptr)
1603 	    {
1604 	      h->u.c.p->section = bfd_make_section_old_way (abfd, "COMMON");
1605 	      h->u.c.p->section->flags |= SEC_ALLOC;
1606 	    }
1607 	  else if (section->owner != abfd)
1608 	    {
1609 	      h->u.c.p->section = bfd_make_section_old_way (abfd,
1610 							    section->name);
1611 	      h->u.c.p->section->flags |= SEC_ALLOC;
1612 	    }
1613 	  else
1614 	    h->u.c.p->section = section;
1615 	  h->linker_def = 0;
1616 	  h->ldscript_def = 0;
1617 	  break;
1618 
1619 	case REF:
1620 	  /* A reference to a defined symbol.  */
1621 	  if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1622 	    h->u.undef.next = h;
1623 	  break;
1624 
1625 	case BIG:
1626 	  /* We have found a common definition for a symbol which
1627 	     already had a common definition.  Use the maximum of the
1628 	     two sizes, and use the section required by the larger symbol.  */
1629 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1630 	  (*info->callbacks->multiple_common) (info, h, abfd,
1631 					       bfd_link_hash_common, value);
1632 	  if (value > h->u.c.size)
1633 	    {
1634 	      unsigned int power;
1635 
1636 	      h->u.c.size = value;
1637 
1638 	      /* Select a default alignment based on the size.  This may
1639 		 be overridden by the caller.  */
1640 	      power = bfd_log2 (value);
1641 	      if (power > 4)
1642 		power = 4;
1643 	      h->u.c.p->alignment_power = power;
1644 
1645 	      /* Some systems have special treatment for small commons,
1646 		 hence we want to select the section used by the larger
1647 		 symbol.  This makes sure the symbol does not go in a
1648 		 small common section if it is now too large.  */
1649 	      if (section == bfd_com_section_ptr)
1650 		{
1651 		  h->u.c.p->section
1652 		    = bfd_make_section_old_way (abfd, "COMMON");
1653 		  h->u.c.p->section->flags |= SEC_ALLOC;
1654 		}
1655 	      else if (section->owner != abfd)
1656 		{
1657 		  h->u.c.p->section
1658 		    = bfd_make_section_old_way (abfd, section->name);
1659 		  h->u.c.p->section->flags |= SEC_ALLOC;
1660 		}
1661 	      else
1662 		h->u.c.p->section = section;
1663 	    }
1664 	  break;
1665 
1666 	case CREF:
1667 	  /* We have found a common definition for a symbol which
1668 	     was already defined.  */
1669 	  (*info->callbacks->multiple_common) (info, h, abfd,
1670 					       bfd_link_hash_common, value);
1671 	  break;
1672 
1673 	case MIND:
1674 	  /* Multiple indirect symbols.  This is OK if they both point
1675 	     to the same symbol.  */
1676 	  if (strcmp (h->u.i.link->root.string, string) == 0)
1677 	    break;
1678 	  /* Fall through.  */
1679 	case MDEF:
1680 	  /* Handle a multiple definition.  */
1681 	  (*info->callbacks->multiple_definition) (info, h,
1682 						   abfd, section, value);
1683 	  break;
1684 
1685 	case CIND:
1686 	  /* Create an indirect symbol from an existing common symbol.  */
1687 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1688 	  (*info->callbacks->multiple_common) (info, h, abfd,
1689 					       bfd_link_hash_indirect, 0);
1690 	  /* Fall through.  */
1691 	case IND:
1692 	  if (inh->type == bfd_link_hash_indirect
1693 	      && inh->u.i.link == h)
1694 	    {
1695 	      _bfd_error_handler
1696 		/* xgettext:c-format */
1697 		(_("%pB: indirect symbol `%s' to `%s' is a loop"),
1698 		 abfd, name, string);
1699 	      bfd_set_error (bfd_error_invalid_operation);
1700 	      return FALSE;
1701 	    }
1702 	  if (inh->type == bfd_link_hash_new)
1703 	    {
1704 	      inh->type = bfd_link_hash_undefined;
1705 	      inh->u.undef.abfd = abfd;
1706 	      bfd_link_add_undef (info->hash, inh);
1707 	    }
1708 
1709 	  /* If the indirect symbol has been referenced, we need to
1710 	     push the reference down to the symbol we are referencing.  */
1711 	  if (h->type != bfd_link_hash_new)
1712 	    {
1713 	      /* ??? If inh->type == bfd_link_hash_undefweak this
1714 		 converts inh to bfd_link_hash_undefined.  */
1715 	      row = UNDEF_ROW;
1716 	      cycle = TRUE;
1717 	    }
1718 
1719 	  h->type = bfd_link_hash_indirect;
1720 	  h->u.i.link = inh;
1721 	  /* Not setting h = h->u.i.link here means that when cycle is
1722 	     set above we'll always go to REFC, and then cycle again
1723 	     to the indirected symbol.  This means that any successful
1724 	     change of an existing symbol to indirect counts as a
1725 	     reference.  ??? That may not be correct when the existing
1726 	     symbol was defweak.  */
1727 	  break;
1728 
1729 	case SET:
1730 	  /* Add an entry to a set.  */
1731 	  (*info->callbacks->add_to_set) (info, h, BFD_RELOC_CTOR,
1732 					  abfd, section, value);
1733 	  break;
1734 
1735 	case WARNC:
1736 	  /* Issue a warning and cycle, except when the reference is
1737 	     in LTO IR.  */
1738 	  if (h->u.i.warning != NULL
1739 	      && (abfd->flags & BFD_PLUGIN) == 0)
1740 	    {
1741 	      (*info->callbacks->warning) (info, h->u.i.warning,
1742 					   h->root.string, abfd, NULL, 0);
1743 	      /* Only issue a warning once.  */
1744 	      h->u.i.warning = NULL;
1745 	    }
1746 	  /* Fall through.  */
1747 	case CYCLE:
1748 	  /* Try again with the referenced symbol.  */
1749 	  h = h->u.i.link;
1750 	  cycle = TRUE;
1751 	  break;
1752 
1753 	case REFC:
1754 	  /* A reference to an indirect symbol.  */
1755 	  if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1756 	    h->u.undef.next = h;
1757 	  h = h->u.i.link;
1758 	  cycle = TRUE;
1759 	  break;
1760 
1761 	case WARN:
1762 	  /* Warn if this symbol has been referenced already from non-IR,
1763 	     otherwise add a warning.  */
1764 	  if ((!info->lto_plugin_active
1765 	       && (h->u.undef.next != NULL || info->hash->undefs_tail == h))
1766 	      || h->non_ir_ref_regular
1767 	      || h->non_ir_ref_dynamic)
1768 	    {
1769 	      (*info->callbacks->warning) (info, string, h->root.string,
1770 					   hash_entry_bfd (h), NULL, 0);
1771 	      break;
1772 	    }
1773 	  /* Fall through.  */
1774 	case MWARN:
1775 	  /* Make a warning symbol.  */
1776 	  {
1777 	    struct bfd_link_hash_entry *sub;
1778 
1779 	    /* STRING is the warning to give.  */
1780 	    sub = ((struct bfd_link_hash_entry *)
1781 		   ((*info->hash->table.newfunc)
1782 		    (NULL, &info->hash->table, h->root.string)));
1783 	    if (sub == NULL)
1784 	      return FALSE;
1785 	    *sub = *h;
1786 	    sub->type = bfd_link_hash_warning;
1787 	    sub->u.i.link = h;
1788 	    if (! copy)
1789 	      sub->u.i.warning = string;
1790 	    else
1791 	      {
1792 		char *w;
1793 		size_t len = strlen (string) + 1;
1794 
1795 		w = (char *) bfd_hash_allocate (&info->hash->table, len);
1796 		if (w == NULL)
1797 		  return FALSE;
1798 		memcpy (w, string, len);
1799 		sub->u.i.warning = w;
1800 	      }
1801 
1802 	    bfd_hash_replace (&info->hash->table,
1803 			      (struct bfd_hash_entry *) h,
1804 			      (struct bfd_hash_entry *) sub);
1805 	    if (hashp != NULL)
1806 	      *hashp = sub;
1807 	  }
1808 	  break;
1809 	}
1810     }
1811   while (cycle);
1812 
1813   return TRUE;
1814 }
1815 
1816 /* Generic final link routine.  */
1817 
1818 bfd_boolean
1819 _bfd_generic_final_link (bfd *abfd, struct bfd_link_info *info)
1820 {
1821   bfd *sub;
1822   asection *o;
1823   struct bfd_link_order *p;
1824   size_t outsymalloc;
1825   struct generic_write_global_symbol_info wginfo;
1826 
1827   bfd_get_outsymbols (abfd) = NULL;
1828   bfd_get_symcount (abfd) = 0;
1829   outsymalloc = 0;
1830 
1831   /* Mark all sections which will be included in the output file.  */
1832   for (o = abfd->sections; o != NULL; o = o->next)
1833     for (p = o->map_head.link_order; p != NULL; p = p->next)
1834       if (p->type == bfd_indirect_link_order)
1835 	p->u.indirect.section->linker_mark = TRUE;
1836 
1837   /* Build the output symbol table.  */
1838   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
1839     if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc))
1840       return FALSE;
1841 
1842   /* Accumulate the global symbols.  */
1843   wginfo.info = info;
1844   wginfo.output_bfd = abfd;
1845   wginfo.psymalloc = &outsymalloc;
1846   _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info),
1847 				   _bfd_generic_link_write_global_symbol,
1848 				   &wginfo);
1849 
1850   /* Make sure we have a trailing NULL pointer on OUTSYMBOLS.  We
1851      shouldn't really need one, since we have SYMCOUNT, but some old
1852      code still expects one.  */
1853   if (! generic_add_output_symbol (abfd, &outsymalloc, NULL))
1854     return FALSE;
1855 
1856   if (bfd_link_relocatable (info))
1857     {
1858       /* Allocate space for the output relocs for each section.  */
1859       for (o = abfd->sections; o != NULL; o = o->next)
1860 	{
1861 	  o->reloc_count = 0;
1862 	  for (p = o->map_head.link_order; p != NULL; p = p->next)
1863 	    {
1864 	      if (p->type == bfd_section_reloc_link_order
1865 		  || p->type == bfd_symbol_reloc_link_order)
1866 		++o->reloc_count;
1867 	      else if (p->type == bfd_indirect_link_order)
1868 		{
1869 		  asection *input_section;
1870 		  bfd *input_bfd;
1871 		  long relsize;
1872 		  arelent **relocs;
1873 		  asymbol **symbols;
1874 		  long reloc_count;
1875 
1876 		  input_section = p->u.indirect.section;
1877 		  input_bfd = input_section->owner;
1878 		  relsize = bfd_get_reloc_upper_bound (input_bfd,
1879 						       input_section);
1880 		  if (relsize < 0)
1881 		    return FALSE;
1882 		  relocs = (arelent **) bfd_malloc (relsize);
1883 		  if (!relocs && relsize != 0)
1884 		    return FALSE;
1885 		  symbols = _bfd_generic_link_get_symbols (input_bfd);
1886 		  reloc_count = bfd_canonicalize_reloc (input_bfd,
1887 							input_section,
1888 							relocs,
1889 							symbols);
1890 		  free (relocs);
1891 		  if (reloc_count < 0)
1892 		    return FALSE;
1893 		  BFD_ASSERT ((unsigned long) reloc_count
1894 			      == input_section->reloc_count);
1895 		  o->reloc_count += reloc_count;
1896 		}
1897 	    }
1898 	  if (o->reloc_count > 0)
1899 	    {
1900 	      bfd_size_type amt;
1901 
1902 	      amt = o->reloc_count;
1903 	      amt *= sizeof (arelent *);
1904 	      o->orelocation = (struct reloc_cache_entry **) bfd_alloc (abfd, amt);
1905 	      if (!o->orelocation)
1906 		return FALSE;
1907 	      o->flags |= SEC_RELOC;
1908 	      /* Reset the count so that it can be used as an index
1909 		 when putting in the output relocs.  */
1910 	      o->reloc_count = 0;
1911 	    }
1912 	}
1913     }
1914 
1915   /* Handle all the link order information for the sections.  */
1916   for (o = abfd->sections; o != NULL; o = o->next)
1917     {
1918       for (p = o->map_head.link_order; p != NULL; p = p->next)
1919 	{
1920 	  switch (p->type)
1921 	    {
1922 	    case bfd_section_reloc_link_order:
1923 	    case bfd_symbol_reloc_link_order:
1924 	      if (! _bfd_generic_reloc_link_order (abfd, info, o, p))
1925 		return FALSE;
1926 	      break;
1927 	    case bfd_indirect_link_order:
1928 	      if (! default_indirect_link_order (abfd, info, o, p, TRUE))
1929 		return FALSE;
1930 	      break;
1931 	    default:
1932 	      if (! _bfd_default_link_order (abfd, info, o, p))
1933 		return FALSE;
1934 	      break;
1935 	    }
1936 	}
1937     }
1938 
1939   return TRUE;
1940 }
1941 
1942 /* Add an output symbol to the output BFD.  */
1943 
1944 static bfd_boolean
1945 generic_add_output_symbol (bfd *output_bfd, size_t *psymalloc, asymbol *sym)
1946 {
1947   if (bfd_get_symcount (output_bfd) >= *psymalloc)
1948     {
1949       asymbol **newsyms;
1950       bfd_size_type amt;
1951 
1952       if (*psymalloc == 0)
1953 	*psymalloc = 124;
1954       else
1955 	*psymalloc *= 2;
1956       amt = *psymalloc;
1957       amt *= sizeof (asymbol *);
1958       newsyms = (asymbol **) bfd_realloc (bfd_get_outsymbols (output_bfd), amt);
1959       if (newsyms == NULL)
1960 	return FALSE;
1961       bfd_get_outsymbols (output_bfd) = newsyms;
1962     }
1963 
1964   bfd_get_outsymbols (output_bfd) [bfd_get_symcount (output_bfd)] = sym;
1965   if (sym != NULL)
1966     ++ bfd_get_symcount (output_bfd);
1967 
1968   return TRUE;
1969 }
1970 
1971 /* Handle the symbols for an input BFD.  */
1972 
1973 bfd_boolean
1974 _bfd_generic_link_output_symbols (bfd *output_bfd,
1975 				  bfd *input_bfd,
1976 				  struct bfd_link_info *info,
1977 				  size_t *psymalloc)
1978 {
1979   asymbol **sym_ptr;
1980   asymbol **sym_end;
1981 
1982   if (!bfd_generic_link_read_symbols (input_bfd))
1983     return FALSE;
1984 
1985   /* Create a filename symbol if we are supposed to.  */
1986   if (info->create_object_symbols_section != NULL)
1987     {
1988       asection *sec;
1989 
1990       for (sec = input_bfd->sections; sec != NULL; sec = sec->next)
1991 	{
1992 	  if (sec->output_section == info->create_object_symbols_section)
1993 	    {
1994 	      asymbol *newsym;
1995 
1996 	      newsym = bfd_make_empty_symbol (input_bfd);
1997 	      if (!newsym)
1998 		return FALSE;
1999 	      newsym->name = input_bfd->filename;
2000 	      newsym->value = 0;
2001 	      newsym->flags = BSF_LOCAL | BSF_FILE;
2002 	      newsym->section = sec;
2003 
2004 	      if (! generic_add_output_symbol (output_bfd, psymalloc,
2005 					       newsym))
2006 		return FALSE;
2007 
2008 	      break;
2009 	    }
2010 	}
2011     }
2012 
2013   /* Adjust the values of the globally visible symbols, and write out
2014      local symbols.  */
2015   sym_ptr = _bfd_generic_link_get_symbols (input_bfd);
2016   sym_end = sym_ptr + _bfd_generic_link_get_symcount (input_bfd);
2017   for (; sym_ptr < sym_end; sym_ptr++)
2018     {
2019       asymbol *sym;
2020       struct generic_link_hash_entry *h;
2021       bfd_boolean output;
2022 
2023       h = NULL;
2024       sym = *sym_ptr;
2025       if ((sym->flags & (BSF_INDIRECT
2026 			 | BSF_WARNING
2027 			 | BSF_GLOBAL
2028 			 | BSF_CONSTRUCTOR
2029 			 | BSF_WEAK)) != 0
2030 	  || bfd_is_und_section (bfd_get_section (sym))
2031 	  || bfd_is_com_section (bfd_get_section (sym))
2032 	  || bfd_is_ind_section (bfd_get_section (sym)))
2033 	{
2034 	  if (sym->udata.p != NULL)
2035 	    h = (struct generic_link_hash_entry *) sym->udata.p;
2036 	  else if ((sym->flags & BSF_CONSTRUCTOR) != 0)
2037 	    {
2038 	      /* This case normally means that the main linker code
2039 		 deliberately ignored this constructor symbol.  We
2040 		 should just pass it through.  This will screw up if
2041 		 the constructor symbol is from a different,
2042 		 non-generic, object file format, but the case will
2043 		 only arise when linking with -r, which will probably
2044 		 fail anyhow, since there will be no way to represent
2045 		 the relocs in the output format being used.  */
2046 	      h = NULL;
2047 	    }
2048 	  else if (bfd_is_und_section (bfd_get_section (sym)))
2049 	    h = ((struct generic_link_hash_entry *)
2050 		 bfd_wrapped_link_hash_lookup (output_bfd, info,
2051 					       bfd_asymbol_name (sym),
2052 					       FALSE, FALSE, TRUE));
2053 	  else
2054 	    h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info),
2055 					       bfd_asymbol_name (sym),
2056 					       FALSE, FALSE, TRUE);
2057 
2058 	  if (h != NULL)
2059 	    {
2060 	      /* Force all references to this symbol to point to
2061 		 the same area in memory.  It is possible that
2062 		 this routine will be called with a hash table
2063 		 other than a generic hash table, so we double
2064 		 check that.  */
2065 	      if (info->output_bfd->xvec == input_bfd->xvec)
2066 		{
2067 		  if (h->sym != NULL)
2068 		    *sym_ptr = sym = h->sym;
2069 		}
2070 
2071 	      switch (h->root.type)
2072 		{
2073 		default:
2074 		case bfd_link_hash_new:
2075 		  abort ();
2076 		case bfd_link_hash_undefined:
2077 		  break;
2078 		case bfd_link_hash_undefweak:
2079 		  sym->flags |= BSF_WEAK;
2080 		  break;
2081 		case bfd_link_hash_indirect:
2082 		  h = (struct generic_link_hash_entry *) h->root.u.i.link;
2083 		  /* fall through */
2084 		case bfd_link_hash_defined:
2085 		  sym->flags |= BSF_GLOBAL;
2086 		  sym->flags &=~ (BSF_WEAK | BSF_CONSTRUCTOR);
2087 		  sym->value = h->root.u.def.value;
2088 		  sym->section = h->root.u.def.section;
2089 		  break;
2090 		case bfd_link_hash_defweak:
2091 		  sym->flags |= BSF_WEAK;
2092 		  sym->flags &=~ BSF_CONSTRUCTOR;
2093 		  sym->value = h->root.u.def.value;
2094 		  sym->section = h->root.u.def.section;
2095 		  break;
2096 		case bfd_link_hash_common:
2097 		  sym->value = h->root.u.c.size;
2098 		  sym->flags |= BSF_GLOBAL;
2099 		  if (! bfd_is_com_section (sym->section))
2100 		    {
2101 		      BFD_ASSERT (bfd_is_und_section (sym->section));
2102 		      sym->section = bfd_com_section_ptr;
2103 		    }
2104 		  /* We do not set the section of the symbol to
2105 		     h->root.u.c.p->section.  That value was saved so
2106 		     that we would know where to allocate the symbol
2107 		     if it was defined.  In this case the type is
2108 		     still bfd_link_hash_common, so we did not define
2109 		     it, so we do not want to use that section.  */
2110 		  break;
2111 		}
2112 	    }
2113 	}
2114 
2115       /* This switch is straight from the old code in
2116 	 write_file_locals in ldsym.c.  */
2117       if (info->strip == strip_all
2118 	  || (info->strip == strip_some
2119 	      && bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym),
2120 				  FALSE, FALSE) == NULL))
2121 	output = FALSE;
2122       else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE)) != 0)
2123 	{
2124 	  /* If this symbol is marked as occurring now, rather
2125 	     than at the end, output it now.  This is used for
2126 	     COFF C_EXT FCN symbols.  FIXME: There must be a
2127 	     better way.  */
2128 	  if (bfd_asymbol_bfd (sym) == input_bfd
2129 	      && (sym->flags & BSF_NOT_AT_END) != 0)
2130 	    output = TRUE;
2131 	  else
2132 	    output = FALSE;
2133 	}
2134       else if (bfd_is_ind_section (sym->section))
2135 	output = FALSE;
2136       else if ((sym->flags & BSF_DEBUGGING) != 0)
2137 	{
2138 	  if (info->strip == strip_none)
2139 	    output = TRUE;
2140 	  else
2141 	    output = FALSE;
2142 	}
2143       else if (bfd_is_und_section (sym->section)
2144 	       || bfd_is_com_section (sym->section))
2145 	output = FALSE;
2146       else if ((sym->flags & BSF_LOCAL) != 0)
2147 	{
2148 	  if ((sym->flags & BSF_WARNING) != 0)
2149 	    output = FALSE;
2150 	  else
2151 	    {
2152 	      switch (info->discard)
2153 		{
2154 		default:
2155 		case discard_all:
2156 		  output = FALSE;
2157 		  break;
2158 		case discard_sec_merge:
2159 		  output = TRUE;
2160 		  if (bfd_link_relocatable (info)
2161 		      || ! (sym->section->flags & SEC_MERGE))
2162 		    break;
2163 		  /* FALLTHROUGH */
2164 		case discard_l:
2165 		  if (bfd_is_local_label (input_bfd, sym))
2166 		    output = FALSE;
2167 		  else
2168 		    output = TRUE;
2169 		  break;
2170 		case discard_none:
2171 		  output = TRUE;
2172 		  break;
2173 		}
2174 	    }
2175 	}
2176       else if ((sym->flags & BSF_CONSTRUCTOR))
2177 	{
2178 	  if (info->strip != strip_all)
2179 	    output = TRUE;
2180 	  else
2181 	    output = FALSE;
2182 	}
2183       else if (sym->flags == 0
2184 	       && (sym->section->owner->flags & BFD_PLUGIN) != 0)
2185 	/* LTO doesn't set symbol information.  We get here with the
2186 	   generic linker for a symbol that was "common" but no longer
2187 	   needs to be global.  */
2188 	output = FALSE;
2189       else
2190 	abort ();
2191 
2192       /* If this symbol is in a section which is not being included
2193 	 in the output file, then we don't want to output the
2194 	 symbol.  */
2195       if (!bfd_is_abs_section (sym->section)
2196 	  && bfd_section_removed_from_list (output_bfd,
2197 					    sym->section->output_section))
2198 	output = FALSE;
2199 
2200       if (output)
2201 	{
2202 	  if (! generic_add_output_symbol (output_bfd, psymalloc, sym))
2203 	    return FALSE;
2204 	  if (h != NULL)
2205 	    h->written = TRUE;
2206 	}
2207     }
2208 
2209   return TRUE;
2210 }
2211 
2212 /* Set the section and value of a generic BFD symbol based on a linker
2213    hash table entry.  */
2214 
2215 static void
2216 set_symbol_from_hash (asymbol *sym, struct bfd_link_hash_entry *h)
2217 {
2218   switch (h->type)
2219     {
2220     default:
2221       abort ();
2222       break;
2223     case bfd_link_hash_new:
2224       /* This can happen when a constructor symbol is seen but we are
2225 	 not building constructors.  */
2226       if (sym->section != NULL)
2227 	{
2228 	  BFD_ASSERT ((sym->flags & BSF_CONSTRUCTOR) != 0);
2229 	}
2230       else
2231 	{
2232 	  sym->flags |= BSF_CONSTRUCTOR;
2233 	  sym->section = bfd_abs_section_ptr;
2234 	  sym->value = 0;
2235 	}
2236       break;
2237     case bfd_link_hash_undefined:
2238       sym->section = bfd_und_section_ptr;
2239       sym->value = 0;
2240       break;
2241     case bfd_link_hash_undefweak:
2242       sym->section = bfd_und_section_ptr;
2243       sym->value = 0;
2244       sym->flags |= BSF_WEAK;
2245       break;
2246     case bfd_link_hash_defined:
2247       sym->section = h->u.def.section;
2248       sym->value = h->u.def.value;
2249       break;
2250     case bfd_link_hash_defweak:
2251       sym->flags |= BSF_WEAK;
2252       sym->section = h->u.def.section;
2253       sym->value = h->u.def.value;
2254       break;
2255     case bfd_link_hash_common:
2256       sym->value = h->u.c.size;
2257       if (sym->section == NULL)
2258 	sym->section = bfd_com_section_ptr;
2259       else if (! bfd_is_com_section (sym->section))
2260 	{
2261 	  BFD_ASSERT (bfd_is_und_section (sym->section));
2262 	  sym->section = bfd_com_section_ptr;
2263 	}
2264       /* Do not set the section; see _bfd_generic_link_output_symbols.  */
2265       break;
2266     case bfd_link_hash_indirect:
2267     case bfd_link_hash_warning:
2268       /* FIXME: What should we do here?  */
2269       break;
2270     }
2271 }
2272 
2273 /* Write out a global symbol, if it hasn't already been written out.
2274    This is called for each symbol in the hash table.  */
2275 
2276 bfd_boolean
2277 _bfd_generic_link_write_global_symbol (struct generic_link_hash_entry *h,
2278 				       void *data)
2279 {
2280   struct generic_write_global_symbol_info *wginfo =
2281       (struct generic_write_global_symbol_info *) data;
2282   asymbol *sym;
2283 
2284   if (h->written)
2285     return TRUE;
2286 
2287   h->written = TRUE;
2288 
2289   if (wginfo->info->strip == strip_all
2290       || (wginfo->info->strip == strip_some
2291 	  && bfd_hash_lookup (wginfo->info->keep_hash, h->root.root.string,
2292 			      FALSE, FALSE) == NULL))
2293     return TRUE;
2294 
2295   if (h->sym != NULL)
2296     sym = h->sym;
2297   else
2298     {
2299       sym = bfd_make_empty_symbol (wginfo->output_bfd);
2300       if (!sym)
2301 	return FALSE;
2302       sym->name = h->root.root.string;
2303       sym->flags = 0;
2304     }
2305 
2306   set_symbol_from_hash (sym, &h->root);
2307 
2308   sym->flags |= BSF_GLOBAL;
2309 
2310   if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc,
2311 				   sym))
2312     {
2313       /* FIXME: No way to return failure.  */
2314       abort ();
2315     }
2316 
2317   return TRUE;
2318 }
2319 
2320 /* Create a relocation.  */
2321 
2322 bfd_boolean
2323 _bfd_generic_reloc_link_order (bfd *abfd,
2324 			       struct bfd_link_info *info,
2325 			       asection *sec,
2326 			       struct bfd_link_order *link_order)
2327 {
2328   arelent *r;
2329 
2330   if (! bfd_link_relocatable (info))
2331     abort ();
2332   if (sec->orelocation == NULL)
2333     abort ();
2334 
2335   r = (arelent *) bfd_alloc (abfd, sizeof (arelent));
2336   if (r == NULL)
2337     return FALSE;
2338 
2339   r->address = link_order->offset;
2340   r->howto = bfd_reloc_type_lookup (abfd, link_order->u.reloc.p->reloc);
2341   if (r->howto == 0)
2342     {
2343       bfd_set_error (bfd_error_bad_value);
2344       return FALSE;
2345     }
2346 
2347   /* Get the symbol to use for the relocation.  */
2348   if (link_order->type == bfd_section_reloc_link_order)
2349     r->sym_ptr_ptr = link_order->u.reloc.p->u.section->symbol_ptr_ptr;
2350   else
2351     {
2352       struct generic_link_hash_entry *h;
2353 
2354       h = ((struct generic_link_hash_entry *)
2355 	   bfd_wrapped_link_hash_lookup (abfd, info,
2356 					 link_order->u.reloc.p->u.name,
2357 					 FALSE, FALSE, TRUE));
2358       if (h == NULL
2359 	  || ! h->written)
2360 	{
2361 	  (*info->callbacks->unattached_reloc)
2362 	    (info, link_order->u.reloc.p->u.name, NULL, NULL, 0);
2363 	  bfd_set_error (bfd_error_bad_value);
2364 	  return FALSE;
2365 	}
2366       r->sym_ptr_ptr = &h->sym;
2367     }
2368 
2369   /* If this is an inplace reloc, write the addend to the object file.
2370      Otherwise, store it in the reloc addend.  */
2371   if (! r->howto->partial_inplace)
2372     r->addend = link_order->u.reloc.p->addend;
2373   else
2374     {
2375       bfd_size_type size;
2376       bfd_reloc_status_type rstat;
2377       bfd_byte *buf;
2378       bfd_boolean ok;
2379       file_ptr loc;
2380 
2381       size = bfd_get_reloc_size (r->howto);
2382       buf = (bfd_byte *) bfd_zmalloc (size);
2383       if (buf == NULL && size != 0)
2384 	return FALSE;
2385       rstat = _bfd_relocate_contents (r->howto, abfd,
2386 				      (bfd_vma) link_order->u.reloc.p->addend,
2387 				      buf);
2388       switch (rstat)
2389 	{
2390 	case bfd_reloc_ok:
2391 	  break;
2392 	default:
2393 	case bfd_reloc_outofrange:
2394 	  abort ();
2395 	case bfd_reloc_overflow:
2396 	  (*info->callbacks->reloc_overflow)
2397 	    (info, NULL,
2398 	     (link_order->type == bfd_section_reloc_link_order
2399 	      ? bfd_section_name (abfd, link_order->u.reloc.p->u.section)
2400 	      : link_order->u.reloc.p->u.name),
2401 	     r->howto->name, link_order->u.reloc.p->addend,
2402 	     NULL, NULL, 0);
2403 	  break;
2404 	}
2405       loc = link_order->offset * bfd_octets_per_byte (abfd);
2406       ok = bfd_set_section_contents (abfd, sec, buf, loc, size);
2407       free (buf);
2408       if (! ok)
2409 	return FALSE;
2410 
2411       r->addend = 0;
2412     }
2413 
2414   sec->orelocation[sec->reloc_count] = r;
2415   ++sec->reloc_count;
2416 
2417   return TRUE;
2418 }
2419 
2420 /* Allocate a new link_order for a section.  */
2421 
2422 struct bfd_link_order *
2423 bfd_new_link_order (bfd *abfd, asection *section)
2424 {
2425   bfd_size_type amt = sizeof (struct bfd_link_order);
2426   struct bfd_link_order *new_lo;
2427 
2428   new_lo = (struct bfd_link_order *) bfd_zalloc (abfd, amt);
2429   if (!new_lo)
2430     return NULL;
2431 
2432   new_lo->type = bfd_undefined_link_order;
2433 
2434   if (section->map_tail.link_order != NULL)
2435     section->map_tail.link_order->next = new_lo;
2436   else
2437     section->map_head.link_order = new_lo;
2438   section->map_tail.link_order = new_lo;
2439 
2440   return new_lo;
2441 }
2442 
2443 /* Default link order processing routine.  Note that we can not handle
2444    the reloc_link_order types here, since they depend upon the details
2445    of how the particular backends generates relocs.  */
2446 
2447 bfd_boolean
2448 _bfd_default_link_order (bfd *abfd,
2449 			 struct bfd_link_info *info,
2450 			 asection *sec,
2451 			 struct bfd_link_order *link_order)
2452 {
2453   switch (link_order->type)
2454     {
2455     case bfd_undefined_link_order:
2456     case bfd_section_reloc_link_order:
2457     case bfd_symbol_reloc_link_order:
2458     default:
2459       abort ();
2460     case bfd_indirect_link_order:
2461       return default_indirect_link_order (abfd, info, sec, link_order,
2462 					  FALSE);
2463     case bfd_data_link_order:
2464       return default_data_link_order (abfd, info, sec, link_order);
2465     }
2466 }
2467 
2468 /* Default routine to handle a bfd_data_link_order.  */
2469 
2470 static bfd_boolean
2471 default_data_link_order (bfd *abfd,
2472 			 struct bfd_link_info *info ATTRIBUTE_UNUSED,
2473 			 asection *sec,
2474 			 struct bfd_link_order *link_order)
2475 {
2476   bfd_size_type size;
2477   size_t fill_size;
2478   bfd_byte *fill;
2479   file_ptr loc;
2480   bfd_boolean result;
2481 
2482   BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0);
2483 
2484   size = link_order->size;
2485   if (size == 0)
2486     return TRUE;
2487 
2488   fill = link_order->u.data.contents;
2489   fill_size = link_order->u.data.size;
2490   if (fill_size == 0)
2491     {
2492       fill = abfd->arch_info->fill (size, bfd_big_endian (abfd),
2493 				    (sec->flags & SEC_CODE) != 0);
2494       if (fill == NULL)
2495 	return FALSE;
2496     }
2497   else if (fill_size < size)
2498     {
2499       bfd_byte *p;
2500       fill = (bfd_byte *) bfd_malloc (size);
2501       if (fill == NULL)
2502 	return FALSE;
2503       p = fill;
2504       if (fill_size == 1)
2505 	memset (p, (int) link_order->u.data.contents[0], (size_t) size);
2506       else
2507 	{
2508 	  do
2509 	    {
2510 	      memcpy (p, link_order->u.data.contents, fill_size);
2511 	      p += fill_size;
2512 	      size -= fill_size;
2513 	    }
2514 	  while (size >= fill_size);
2515 	  if (size != 0)
2516 	    memcpy (p, link_order->u.data.contents, (size_t) size);
2517 	  size = link_order->size;
2518 	}
2519     }
2520 
2521   loc = link_order->offset * bfd_octets_per_byte (abfd);
2522   result = bfd_set_section_contents (abfd, sec, fill, loc, size);
2523 
2524   if (fill != link_order->u.data.contents)
2525     free (fill);
2526   return result;
2527 }
2528 
2529 /* Default routine to handle a bfd_indirect_link_order.  */
2530 
2531 static bfd_boolean
2532 default_indirect_link_order (bfd *output_bfd,
2533 			     struct bfd_link_info *info,
2534 			     asection *output_section,
2535 			     struct bfd_link_order *link_order,
2536 			     bfd_boolean generic_linker)
2537 {
2538   asection *input_section;
2539   bfd *input_bfd;
2540   bfd_byte *contents = NULL;
2541   bfd_byte *new_contents;
2542   bfd_size_type sec_size;
2543   file_ptr loc;
2544 
2545   BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0);
2546 
2547   input_section = link_order->u.indirect.section;
2548   input_bfd = input_section->owner;
2549   if (input_section->size == 0)
2550     return TRUE;
2551 
2552   BFD_ASSERT (input_section->output_section == output_section);
2553   BFD_ASSERT (input_section->output_offset == link_order->offset);
2554   BFD_ASSERT (input_section->size == link_order->size);
2555 
2556   if (bfd_link_relocatable (info)
2557       && input_section->reloc_count > 0
2558       && output_section->orelocation == NULL)
2559     {
2560       /* Space has not been allocated for the output relocations.
2561 	 This can happen when we are called by a specific backend
2562 	 because somebody is attempting to link together different
2563 	 types of object files.  Handling this case correctly is
2564 	 difficult, and sometimes impossible.  */
2565       _bfd_error_handler
2566 	/* xgettext:c-format */
2567 	(_("attempt to do relocatable link with %s input and %s output"),
2568 	 bfd_get_target (input_bfd), bfd_get_target (output_bfd));
2569       bfd_set_error (bfd_error_wrong_format);
2570       return FALSE;
2571     }
2572 
2573   if (! generic_linker)
2574     {
2575       asymbol **sympp;
2576       asymbol **symppend;
2577 
2578       /* Get the canonical symbols.  The generic linker will always
2579 	 have retrieved them by this point, but we are being called by
2580 	 a specific linker, presumably because we are linking
2581 	 different types of object files together.  */
2582       if (!bfd_generic_link_read_symbols (input_bfd))
2583 	return FALSE;
2584 
2585       /* Since we have been called by a specific linker, rather than
2586 	 the generic linker, the values of the symbols will not be
2587 	 right.  They will be the values as seen in the input file,
2588 	 not the values of the final link.  We need to fix them up
2589 	 before we can relocate the section.  */
2590       sympp = _bfd_generic_link_get_symbols (input_bfd);
2591       symppend = sympp + _bfd_generic_link_get_symcount (input_bfd);
2592       for (; sympp < symppend; sympp++)
2593 	{
2594 	  asymbol *sym;
2595 	  struct bfd_link_hash_entry *h;
2596 
2597 	  sym = *sympp;
2598 
2599 	  if ((sym->flags & (BSF_INDIRECT
2600 			     | BSF_WARNING
2601 			     | BSF_GLOBAL
2602 			     | BSF_CONSTRUCTOR
2603 			     | BSF_WEAK)) != 0
2604 	      || bfd_is_und_section (bfd_get_section (sym))
2605 	      || bfd_is_com_section (bfd_get_section (sym))
2606 	      || bfd_is_ind_section (bfd_get_section (sym)))
2607 	    {
2608 	      /* sym->udata may have been set by
2609 		 generic_link_add_symbol_list.  */
2610 	      if (sym->udata.p != NULL)
2611 		h = (struct bfd_link_hash_entry *) sym->udata.p;
2612 	      else if (bfd_is_und_section (bfd_get_section (sym)))
2613 		h = bfd_wrapped_link_hash_lookup (output_bfd, info,
2614 						  bfd_asymbol_name (sym),
2615 						  FALSE, FALSE, TRUE);
2616 	      else
2617 		h = bfd_link_hash_lookup (info->hash,
2618 					  bfd_asymbol_name (sym),
2619 					  FALSE, FALSE, TRUE);
2620 	      if (h != NULL)
2621 		set_symbol_from_hash (sym, h);
2622 	    }
2623 	}
2624     }
2625 
2626   if ((output_section->flags & (SEC_GROUP | SEC_LINKER_CREATED)) == SEC_GROUP
2627       && input_section->size != 0)
2628     {
2629       /* Group section contents are set by bfd_elf_set_group_contents.  */
2630       if (!output_bfd->output_has_begun)
2631 	{
2632 	  /* FIXME: This hack ensures bfd_elf_set_group_contents is called.  */
2633 	  if (!bfd_set_section_contents (output_bfd, output_section, "", 0, 1))
2634 	    goto error_return;
2635 	}
2636       new_contents = output_section->contents;
2637       BFD_ASSERT (new_contents != NULL);
2638       BFD_ASSERT (input_section->output_offset == 0);
2639     }
2640   else
2641     {
2642       /* Get and relocate the section contents.  */
2643       sec_size = (input_section->rawsize > input_section->size
2644 		  ? input_section->rawsize
2645 		  : input_section->size);
2646       contents = (bfd_byte *) bfd_malloc (sec_size);
2647       if (contents == NULL && sec_size != 0)
2648 	goto error_return;
2649       new_contents = (bfd_get_relocated_section_contents
2650 		      (output_bfd, info, link_order, contents,
2651 		       bfd_link_relocatable (info),
2652 		       _bfd_generic_link_get_symbols (input_bfd)));
2653       if (!new_contents)
2654 	goto error_return;
2655     }
2656 
2657   /* Output the section contents.  */
2658   loc = input_section->output_offset * bfd_octets_per_byte (output_bfd);
2659   if (! bfd_set_section_contents (output_bfd, output_section,
2660 				  new_contents, loc, input_section->size))
2661     goto error_return;
2662 
2663   if (contents != NULL)
2664     free (contents);
2665   return TRUE;
2666 
2667  error_return:
2668   if (contents != NULL)
2669     free (contents);
2670   return FALSE;
2671 }
2672 
2673 /* A little routine to count the number of relocs in a link_order
2674    list.  */
2675 
2676 unsigned int
2677 _bfd_count_link_order_relocs (struct bfd_link_order *link_order)
2678 {
2679   register unsigned int c;
2680   register struct bfd_link_order *l;
2681 
2682   c = 0;
2683   for (l = link_order; l != NULL; l = l->next)
2684     {
2685       if (l->type == bfd_section_reloc_link_order
2686 	  || l->type == bfd_symbol_reloc_link_order)
2687 	++c;
2688     }
2689 
2690   return c;
2691 }
2692 
2693 /*
2694 FUNCTION
2695 	bfd_link_split_section
2696 
2697 SYNOPSIS
2698 	bfd_boolean bfd_link_split_section (bfd *abfd, asection *sec);
2699 
2700 DESCRIPTION
2701 	Return nonzero if @var{sec} should be split during a
2702 	reloceatable or final link.
2703 
2704 .#define bfd_link_split_section(abfd, sec) \
2705 .	BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2706 .
2707 
2708 */
2709 
2710 bfd_boolean
2711 _bfd_generic_link_split_section (bfd *abfd ATTRIBUTE_UNUSED,
2712 				 asection *sec ATTRIBUTE_UNUSED)
2713 {
2714   return FALSE;
2715 }
2716 
2717 /*
2718 FUNCTION
2719 	bfd_section_already_linked
2720 
2721 SYNOPSIS
2722 	bfd_boolean bfd_section_already_linked (bfd *abfd,
2723 						asection *sec,
2724 						struct bfd_link_info *info);
2725 
2726 DESCRIPTION
2727 	Check if @var{data} has been already linked during a reloceatable
2728 	or final link.  Return TRUE if it has.
2729 
2730 .#define bfd_section_already_linked(abfd, sec, info) \
2731 .	BFD_SEND (abfd, _section_already_linked, (abfd, sec, info))
2732 .
2733 
2734 */
2735 
2736 /* Sections marked with the SEC_LINK_ONCE flag should only be linked
2737    once into the output.  This routine checks each section, and
2738    arrange to discard it if a section of the same name has already
2739    been linked.  This code assumes that all relevant sections have the
2740    SEC_LINK_ONCE flag set; that is, it does not depend solely upon the
2741    section name.  bfd_section_already_linked is called via
2742    bfd_map_over_sections.  */
2743 
2744 /* The hash table.  */
2745 
2746 static struct bfd_hash_table _bfd_section_already_linked_table;
2747 
2748 /* Support routines for the hash table used by section_already_linked,
2749    initialize the table, traverse, lookup, fill in an entry and remove
2750    the table.  */
2751 
2752 void
2753 bfd_section_already_linked_table_traverse
2754   (bfd_boolean (*func) (struct bfd_section_already_linked_hash_entry *,
2755 			void *), void *info)
2756 {
2757   bfd_hash_traverse (&_bfd_section_already_linked_table,
2758 		     (bfd_boolean (*) (struct bfd_hash_entry *,
2759 				       void *)) func,
2760 		     info);
2761 }
2762 
2763 struct bfd_section_already_linked_hash_entry *
2764 bfd_section_already_linked_table_lookup (const char *name)
2765 {
2766   return ((struct bfd_section_already_linked_hash_entry *)
2767 	  bfd_hash_lookup (&_bfd_section_already_linked_table, name,
2768 			   TRUE, FALSE));
2769 }
2770 
2771 bfd_boolean
2772 bfd_section_already_linked_table_insert
2773   (struct bfd_section_already_linked_hash_entry *already_linked_list,
2774    asection *sec)
2775 {
2776   struct bfd_section_already_linked *l;
2777 
2778   /* Allocate the memory from the same obstack as the hash table is
2779      kept in.  */
2780   l = (struct bfd_section_already_linked *)
2781       bfd_hash_allocate (&_bfd_section_already_linked_table, sizeof *l);
2782   if (l == NULL)
2783     return FALSE;
2784   l->sec = sec;
2785   l->next = already_linked_list->entry;
2786   already_linked_list->entry = l;
2787   return TRUE;
2788 }
2789 
2790 static struct bfd_hash_entry *
2791 already_linked_newfunc (struct bfd_hash_entry *entry ATTRIBUTE_UNUSED,
2792 			struct bfd_hash_table *table,
2793 			const char *string ATTRIBUTE_UNUSED)
2794 {
2795   struct bfd_section_already_linked_hash_entry *ret =
2796     (struct bfd_section_already_linked_hash_entry *)
2797       bfd_hash_allocate (table, sizeof *ret);
2798 
2799   if (ret == NULL)
2800     return NULL;
2801 
2802   ret->entry = NULL;
2803 
2804   return &ret->root;
2805 }
2806 
2807 bfd_boolean
2808 bfd_section_already_linked_table_init (void)
2809 {
2810   return bfd_hash_table_init_n (&_bfd_section_already_linked_table,
2811 				already_linked_newfunc,
2812 				sizeof (struct bfd_section_already_linked_hash_entry),
2813 				42);
2814 }
2815 
2816 void
2817 bfd_section_already_linked_table_free (void)
2818 {
2819   bfd_hash_table_free (&_bfd_section_already_linked_table);
2820 }
2821 
2822 /* Report warnings as appropriate for duplicate section SEC.
2823    Return FALSE if we decide to keep SEC after all.  */
2824 
2825 bfd_boolean
2826 _bfd_handle_already_linked (asection *sec,
2827 			    struct bfd_section_already_linked *l,
2828 			    struct bfd_link_info *info)
2829 {
2830   switch (sec->flags & SEC_LINK_DUPLICATES)
2831     {
2832     default:
2833       abort ();
2834 
2835     case SEC_LINK_DUPLICATES_DISCARD:
2836       /* If we found an LTO IR match for this comdat group on
2837 	 the first pass, replace it with the LTO output on the
2838 	 second pass.  We can't simply choose real object
2839 	 files over IR because the first pass may contain a
2840 	 mix of LTO and normal objects and we must keep the
2841 	 first match, be it IR or real.  */
2842       if (sec->owner->lto_output
2843 	  && (l->sec->owner->flags & BFD_PLUGIN) != 0)
2844 	{
2845 	  l->sec = sec;
2846 	  return FALSE;
2847 	}
2848       break;
2849 
2850     case SEC_LINK_DUPLICATES_ONE_ONLY:
2851       info->callbacks->einfo
2852 	/* xgettext:c-format */
2853 	(_("%pB: ignoring duplicate section `%pA'\n"),
2854 	 sec->owner, sec);
2855       break;
2856 
2857     case SEC_LINK_DUPLICATES_SAME_SIZE:
2858       if ((l->sec->owner->flags & BFD_PLUGIN) != 0)
2859 	;
2860       else if (sec->size != l->sec->size)
2861 	info->callbacks->einfo
2862 	  /* xgettext:c-format */
2863 	  (_("%pB: duplicate section `%pA' has different size\n"),
2864 	   sec->owner, sec);
2865       break;
2866 
2867     case SEC_LINK_DUPLICATES_SAME_CONTENTS:
2868       if ((l->sec->owner->flags & BFD_PLUGIN) != 0)
2869 	;
2870       else if (sec->size != l->sec->size)
2871 	info->callbacks->einfo
2872 	  /* xgettext:c-format */
2873 	  (_("%pB: duplicate section `%pA' has different size\n"),
2874 	   sec->owner, sec);
2875       else if (sec->size != 0)
2876 	{
2877 	  bfd_byte *sec_contents, *l_sec_contents = NULL;
2878 
2879 	  if (!bfd_malloc_and_get_section (sec->owner, sec, &sec_contents))
2880 	    info->callbacks->einfo
2881 	      /* xgettext:c-format */
2882 	      (_("%pB: could not read contents of section `%pA'\n"),
2883 	       sec->owner, sec);
2884 	  else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
2885 						&l_sec_contents))
2886 	    info->callbacks->einfo
2887 	      /* xgettext:c-format */
2888 	      (_("%pB: could not read contents of section `%pA'\n"),
2889 	       l->sec->owner, l->sec);
2890 	  else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
2891 	    info->callbacks->einfo
2892 	      /* xgettext:c-format */
2893 	      (_("%pB: duplicate section `%pA' has different contents\n"),
2894 	       sec->owner, sec);
2895 
2896 	  if (sec_contents)
2897 	    free (sec_contents);
2898 	  if (l_sec_contents)
2899 	    free (l_sec_contents);
2900 	}
2901       break;
2902     }
2903 
2904   /* Set the output_section field so that lang_add_section
2905      does not create a lang_input_section structure for this
2906      section.  Since there might be a symbol in the section
2907      being discarded, we must retain a pointer to the section
2908      which we are really going to use.  */
2909   sec->output_section = bfd_abs_section_ptr;
2910   sec->kept_section = l->sec;
2911   return TRUE;
2912 }
2913 
2914 /* This is used on non-ELF inputs.  */
2915 
2916 bfd_boolean
2917 _bfd_generic_section_already_linked (bfd *abfd ATTRIBUTE_UNUSED,
2918 				     asection *sec,
2919 				     struct bfd_link_info *info)
2920 {
2921   const char *name;
2922   struct bfd_section_already_linked *l;
2923   struct bfd_section_already_linked_hash_entry *already_linked_list;
2924 
2925   if ((sec->flags & SEC_LINK_ONCE) == 0)
2926     return FALSE;
2927 
2928   /* The generic linker doesn't handle section groups.  */
2929   if ((sec->flags & SEC_GROUP) != 0)
2930     return FALSE;
2931 
2932   /* FIXME: When doing a relocatable link, we may have trouble
2933      copying relocations in other sections that refer to local symbols
2934      in the section being discarded.  Those relocations will have to
2935      be converted somehow; as of this writing I'm not sure that any of
2936      the backends handle that correctly.
2937 
2938      It is tempting to instead not discard link once sections when
2939      doing a relocatable link (technically, they should be discarded
2940      whenever we are building constructors).  However, that fails,
2941      because the linker winds up combining all the link once sections
2942      into a single large link once section, which defeats the purpose
2943      of having link once sections in the first place.  */
2944 
2945   name = bfd_get_section_name (abfd, sec);
2946 
2947   already_linked_list = bfd_section_already_linked_table_lookup (name);
2948 
2949   l = already_linked_list->entry;
2950   if (l != NULL)
2951     {
2952       /* The section has already been linked.  See if we should
2953 	 issue a warning.  */
2954       return _bfd_handle_already_linked (sec, l, info);
2955     }
2956 
2957   /* This is the first section with this name.  Record it.  */
2958   if (!bfd_section_already_linked_table_insert (already_linked_list, sec))
2959     info->callbacks->einfo (_("%F%P: already_linked_table: %E\n"));
2960   return FALSE;
2961 }
2962 
2963 /* Choose a neighbouring section to S in OBFD that will be output, or
2964    the absolute section if ADDR is out of bounds of the neighbours.  */
2965 
2966 asection *
2967 _bfd_nearby_section (bfd *obfd, asection *s, bfd_vma addr)
2968 {
2969   asection *next, *prev, *best;
2970 
2971   /* Find preceding kept section.  */
2972   for (prev = s->prev; prev != NULL; prev = prev->prev)
2973     if ((prev->flags & SEC_EXCLUDE) == 0
2974 	&& !bfd_section_removed_from_list (obfd, prev))
2975       break;
2976 
2977   /* Find following kept section.  Start at prev->next because
2978      other sections may have been added after S was removed.  */
2979   if (s->prev != NULL)
2980     next = s->prev->next;
2981   else
2982     next = s->owner->sections;
2983   for (; next != NULL; next = next->next)
2984     if ((next->flags & SEC_EXCLUDE) == 0
2985 	&& !bfd_section_removed_from_list (obfd, next))
2986       break;
2987 
2988   /* Choose better of two sections, based on flags.  The idea
2989      is to choose a section that will be in the same segment
2990      as S would have been if it was kept.  */
2991   best = next;
2992   if (prev == NULL)
2993     {
2994       if (next == NULL)
2995 	best = bfd_abs_section_ptr;
2996     }
2997   else if (next == NULL)
2998     best = prev;
2999   else if (((prev->flags ^ next->flags)
3000 	    & (SEC_ALLOC | SEC_THREAD_LOCAL | SEC_LOAD)) != 0)
3001     {
3002       if (((next->flags ^ s->flags)
3003 	   & (SEC_ALLOC | SEC_THREAD_LOCAL)) != 0
3004 	  /* We prefer to choose a loaded section.  Section S
3005 	     doesn't have SEC_LOAD set (it being excluded, that
3006 	     part of the flag processing didn't happen) so we
3007 	     can't compare that flag to those of NEXT and PREV.  */
3008 	  || ((prev->flags & SEC_LOAD) != 0
3009 	      && (next->flags & SEC_LOAD) == 0))
3010 	best = prev;
3011     }
3012   else if (((prev->flags ^ next->flags) & SEC_READONLY) != 0)
3013     {
3014       if (((next->flags ^ s->flags) & SEC_READONLY) != 0)
3015 	best = prev;
3016     }
3017   else if (((prev->flags ^ next->flags) & SEC_CODE) != 0)
3018     {
3019       if (((next->flags ^ s->flags) & SEC_CODE) != 0)
3020 	best = prev;
3021     }
3022   else
3023     {
3024       /* Flags we care about are the same.  Prefer the following
3025 	 section if that will result in a positive valued sym.  */
3026       if (addr < next->vma)
3027 	best = prev;
3028     }
3029 
3030   return best;
3031 }
3032 
3033 /* Convert symbols in excluded output sections to use a kept section.  */
3034 
3035 static bfd_boolean
3036 fix_syms (struct bfd_link_hash_entry *h, void *data)
3037 {
3038   bfd *obfd = (bfd *) data;
3039 
3040   if (h->type == bfd_link_hash_defined
3041       || h->type == bfd_link_hash_defweak)
3042     {
3043       asection *s = h->u.def.section;
3044       if (s != NULL
3045 	  && s->output_section != NULL
3046 	  && (s->output_section->flags & SEC_EXCLUDE) != 0
3047 	  && bfd_section_removed_from_list (obfd, s->output_section))
3048 	{
3049 	  asection *op;
3050 
3051 	  h->u.def.value += s->output_offset + s->output_section->vma;
3052 	  op = _bfd_nearby_section (obfd, s->output_section, h->u.def.value);
3053 	  h->u.def.value -= op->vma;
3054 	  h->u.def.section = op;
3055 	}
3056     }
3057 
3058   return TRUE;
3059 }
3060 
3061 void
3062 _bfd_fix_excluded_sec_syms (bfd *obfd, struct bfd_link_info *info)
3063 {
3064   bfd_link_hash_traverse (info->hash, fix_syms, obfd);
3065 }
3066 
3067 /*
3068 FUNCTION
3069 	bfd_generic_define_common_symbol
3070 
3071 SYNOPSIS
3072 	bfd_boolean bfd_generic_define_common_symbol
3073 	  (bfd *output_bfd, struct bfd_link_info *info,
3074 	   struct bfd_link_hash_entry *h);
3075 
3076 DESCRIPTION
3077 	Convert common symbol @var{h} into a defined symbol.
3078 	Return TRUE on success and FALSE on failure.
3079 
3080 .#define bfd_define_common_symbol(output_bfd, info, h) \
3081 .	BFD_SEND (output_bfd, _bfd_define_common_symbol, (output_bfd, info, h))
3082 .
3083 */
3084 
3085 bfd_boolean
3086 bfd_generic_define_common_symbol (bfd *output_bfd,
3087 				  struct bfd_link_info *info ATTRIBUTE_UNUSED,
3088 				  struct bfd_link_hash_entry *h)
3089 {
3090   unsigned int power_of_two;
3091   bfd_vma alignment, size;
3092   asection *section;
3093 
3094   BFD_ASSERT (h != NULL && h->type == bfd_link_hash_common);
3095 
3096   size = h->u.c.size;
3097   power_of_two = h->u.c.p->alignment_power;
3098   section = h->u.c.p->section;
3099 
3100   /* Increase the size of the section to align the common symbol.
3101      The alignment must be a power of two.  */
3102   alignment = bfd_octets_per_byte (output_bfd) << power_of_two;
3103   BFD_ASSERT (alignment != 0 && (alignment & -alignment) == alignment);
3104   section->size += alignment - 1;
3105   section->size &= -alignment;
3106 
3107   /* Adjust the section's overall alignment if necessary.  */
3108   if (power_of_two > section->alignment_power)
3109     section->alignment_power = power_of_two;
3110 
3111   /* Change the symbol from common to defined.  */
3112   h->type = bfd_link_hash_defined;
3113   h->u.def.section = section;
3114   h->u.def.value = section->size;
3115 
3116   /* Increase the size of the section.  */
3117   section->size += size;
3118 
3119   /* Make sure the section is allocated in memory, and make sure that
3120      it is no longer a common section.  */
3121   section->flags |= SEC_ALLOC;
3122   section->flags &= ~(SEC_IS_COMMON | SEC_HAS_CONTENTS);
3123   return TRUE;
3124 }
3125 
3126 /*
3127 FUNCTION
3128 	_bfd_generic_link_hide_symbol
3129 
3130 SYNOPSIS
3131 	void _bfd_generic_link_hide_symbol
3132 	  (bfd *output_bfd, struct bfd_link_info *info,
3133 	   struct bfd_link_hash_entry *h);
3134 
3135 DESCRIPTION
3136 	Hide symbol @var{h}.
3137 	This is an internal function.  It should not be called from
3138 	outside the BFD library.
3139 
3140 .#define bfd_link_hide_symbol(output_bfd, info, h) \
3141 .	BFD_SEND (output_bfd, _bfd_link_hide_symbol, (output_bfd, info, h))
3142 .
3143 */
3144 
3145 void
3146 _bfd_generic_link_hide_symbol (bfd *output_bfd ATTRIBUTE_UNUSED,
3147 			       struct bfd_link_info *info ATTRIBUTE_UNUSED,
3148 			       struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED)
3149 {
3150 }
3151 
3152 /*
3153 FUNCTION
3154 	bfd_generic_define_start_stop
3155 
3156 SYNOPSIS
3157 	struct bfd_link_hash_entry *bfd_generic_define_start_stop
3158 	  (struct bfd_link_info *info,
3159 	   const char *symbol, asection *sec);
3160 
3161 DESCRIPTION
3162 	Define a __start, __stop, .startof. or .sizeof. symbol.
3163 	Return the symbol or NULL if no such undefined symbol exists.
3164 
3165 .#define bfd_define_start_stop(output_bfd, info, symbol, sec) \
3166 .	BFD_SEND (output_bfd, _bfd_define_start_stop, (info, symbol, sec))
3167 .
3168 */
3169 
3170 struct bfd_link_hash_entry *
3171 bfd_generic_define_start_stop (struct bfd_link_info *info,
3172 			       const char *symbol, asection *sec)
3173 {
3174   struct bfd_link_hash_entry *h;
3175 
3176   h = bfd_link_hash_lookup (info->hash, symbol, FALSE, FALSE, TRUE);
3177   if (h != NULL
3178       && (h->type == bfd_link_hash_undefined
3179 	  || h->type == bfd_link_hash_undefweak))
3180     {
3181       h->type = bfd_link_hash_defined;
3182       h->u.def.section = sec;
3183       h->u.def.value = 0;
3184       return h;
3185     }
3186   return NULL;
3187 }
3188 
3189 /*
3190 FUNCTION
3191 	bfd_find_version_for_sym
3192 
3193 SYNOPSIS
3194 	struct bfd_elf_version_tree * bfd_find_version_for_sym
3195 	  (struct bfd_elf_version_tree *verdefs,
3196 	   const char *sym_name, bfd_boolean *hide);
3197 
3198 DESCRIPTION
3199 	Search an elf version script tree for symbol versioning
3200 	info and export / don't-export status for a given symbol.
3201 	Return non-NULL on success and NULL on failure; also sets
3202 	the output @samp{hide} boolean parameter.
3203 
3204 */
3205 
3206 struct bfd_elf_version_tree *
3207 bfd_find_version_for_sym (struct bfd_elf_version_tree *verdefs,
3208 			  const char *sym_name,
3209 			  bfd_boolean *hide)
3210 {
3211   struct bfd_elf_version_tree *t;
3212   struct bfd_elf_version_tree *local_ver, *global_ver, *exist_ver;
3213   struct bfd_elf_version_tree *star_local_ver, *star_global_ver;
3214 
3215   local_ver = NULL;
3216   global_ver = NULL;
3217   star_local_ver = NULL;
3218   star_global_ver = NULL;
3219   exist_ver = NULL;
3220   for (t = verdefs; t != NULL; t = t->next)
3221     {
3222       if (t->globals.list != NULL)
3223 	{
3224 	  struct bfd_elf_version_expr *d = NULL;
3225 
3226 	  while ((d = (*t->match) (&t->globals, d, sym_name)) != NULL)
3227 	    {
3228 	      if (d->literal || strcmp (d->pattern, "*") != 0)
3229 		global_ver = t;
3230 	      else
3231 		star_global_ver = t;
3232 	      if (d->symver)
3233 		exist_ver = t;
3234 	      d->script = 1;
3235 	      /* If the match is a wildcard pattern, keep looking for
3236 		 a more explicit, perhaps even local, match.  */
3237 	      if (d->literal)
3238 		break;
3239 	    }
3240 
3241 	  if (d != NULL)
3242 	    break;
3243 	}
3244 
3245       if (t->locals.list != NULL)
3246 	{
3247 	  struct bfd_elf_version_expr *d = NULL;
3248 
3249 	  while ((d = (*t->match) (&t->locals, d, sym_name)) != NULL)
3250 	    {
3251 	      if (d->literal || strcmp (d->pattern, "*") != 0)
3252 		local_ver = t;
3253 	      else
3254 		star_local_ver = t;
3255 	      /* If the match is a wildcard pattern, keep looking for
3256 		 a more explicit, perhaps even global, match.  */
3257 	      if (d->literal)
3258 		{
3259 		  /* An exact match overrides a global wildcard.  */
3260 		  global_ver = NULL;
3261 		  star_global_ver = NULL;
3262 		  break;
3263 		}
3264 	    }
3265 
3266 	  if (d != NULL)
3267 	    break;
3268 	}
3269     }
3270 
3271   if (global_ver == NULL && local_ver == NULL)
3272     global_ver = star_global_ver;
3273 
3274   if (global_ver != NULL)
3275     {
3276       /* If we already have a versioned symbol that matches the
3277 	 node for this symbol, then we don't want to create a
3278 	 duplicate from the unversioned symbol.  Instead hide the
3279 	 unversioned symbol.  */
3280       *hide = exist_ver == global_ver;
3281       return global_ver;
3282     }
3283 
3284   if (local_ver == NULL)
3285     local_ver = star_local_ver;
3286 
3287   if (local_ver != NULL)
3288     {
3289       *hide = TRUE;
3290       return local_ver;
3291     }
3292 
3293   return NULL;
3294 }
3295 
3296 /*
3297 FUNCTION
3298 	bfd_hide_sym_by_version
3299 
3300 SYNOPSIS
3301 	bfd_boolean bfd_hide_sym_by_version
3302 	  (struct bfd_elf_version_tree *verdefs, const char *sym_name);
3303 
3304 DESCRIPTION
3305 	Search an elf version script tree for symbol versioning
3306 	info for a given symbol.  Return TRUE if the symbol is hidden.
3307 
3308 */
3309 
3310 bfd_boolean
3311 bfd_hide_sym_by_version (struct bfd_elf_version_tree *verdefs,
3312 			 const char *sym_name)
3313 {
3314   bfd_boolean hidden = FALSE;
3315   bfd_find_version_for_sym (verdefs, sym_name, &hidden);
3316   return hidden;
3317 }
3318 
3319 /*
3320 FUNCTION
3321 	bfd_link_check_relocs
3322 
3323 SYNOPSIS
3324 	bfd_boolean bfd_link_check_relocs
3325 	  (bfd *abfd, struct bfd_link_info *info);
3326 
3327 DESCRIPTION
3328 	Checks the relocs in ABFD for validity.
3329 	Does not execute the relocs.
3330 	Return TRUE if everything is OK, FALSE otherwise.
3331 	This is the external entry point to this code.
3332 */
3333 
3334 bfd_boolean
3335 bfd_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
3336 {
3337   return BFD_SEND (abfd, _bfd_link_check_relocs, (abfd, info));
3338 }
3339 
3340 /*
3341 FUNCTION
3342 	_bfd_generic_link_check_relocs
3343 
3344 SYNOPSIS
3345 	bfd_boolean _bfd_generic_link_check_relocs
3346 	  (bfd *abfd, struct bfd_link_info *info);
3347 
3348 DESCRIPTION
3349 	Stub function for targets that do not implement reloc checking.
3350 	Return TRUE.
3351 	This is an internal function.  It should not be called from
3352 	outside the BFD library.
3353 */
3354 
3355 bfd_boolean
3356 _bfd_generic_link_check_relocs (bfd *abfd ATTRIBUTE_UNUSED,
3357 				struct bfd_link_info *info ATTRIBUTE_UNUSED)
3358 {
3359   return TRUE;
3360 }
3361 
3362 /*
3363 FUNCTION
3364 	bfd_merge_private_bfd_data
3365 
3366 SYNOPSIS
3367 	bfd_boolean bfd_merge_private_bfd_data
3368 	  (bfd *ibfd, struct bfd_link_info *info);
3369 
3370 DESCRIPTION
3371 	Merge private BFD information from the BFD @var{ibfd} to the
3372 	the output file BFD when linking.  Return <<TRUE>> on success,
3373 	<<FALSE>> on error.  Possible error returns are:
3374 
3375 	o <<bfd_error_no_memory>> -
3376 	Not enough memory exists to create private data for @var{obfd}.
3377 
3378 .#define bfd_merge_private_bfd_data(ibfd, info) \
3379 .	BFD_SEND ((info)->output_bfd, _bfd_merge_private_bfd_data, \
3380 .		  (ibfd, info))
3381 */
3382 
3383 /*
3384 INTERNAL_FUNCTION
3385 	_bfd_generic_verify_endian_match
3386 
3387 SYNOPSIS
3388 	bfd_boolean _bfd_generic_verify_endian_match
3389 	  (bfd *ibfd, struct bfd_link_info *info);
3390 
3391 DESCRIPTION
3392 	Can be used from / for bfd_merge_private_bfd_data to check that
3393 	endianness matches between input and output file.  Returns
3394 	TRUE for a match, otherwise returns FALSE and emits an error.
3395 */
3396 
3397 bfd_boolean
3398 _bfd_generic_verify_endian_match (bfd *ibfd, struct bfd_link_info *info)
3399 {
3400   bfd *obfd = info->output_bfd;
3401 
3402   if (ibfd->xvec->byteorder != obfd->xvec->byteorder
3403       && ibfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN
3404       && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
3405     {
3406       if (bfd_big_endian (ibfd))
3407 	_bfd_error_handler (_("%pB: compiled for a big endian system "
3408 			      "and target is little endian"), ibfd);
3409       else
3410 	_bfd_error_handler (_("%pB: compiled for a little endian system "
3411 			      "and target is big endian"), ibfd);
3412       bfd_set_error (bfd_error_wrong_format);
3413       return FALSE;
3414     }
3415 
3416   return TRUE;
3417 }
3418 
3419 int
3420 _bfd_nolink_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
3421 			    struct bfd_link_info *info ATTRIBUTE_UNUSED)
3422 {
3423   return 0;
3424 }
3425 
3426 bfd_boolean
3427 _bfd_nolink_bfd_relax_section (bfd *abfd,
3428 			       asection *section ATTRIBUTE_UNUSED,
3429 			       struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
3430 			       bfd_boolean *again ATTRIBUTE_UNUSED)
3431 {
3432   return _bfd_bool_bfd_false_error (abfd);
3433 }
3434 
3435 bfd_byte *
3436 _bfd_nolink_bfd_get_relocated_section_contents
3437     (bfd *abfd,
3438      struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
3439      struct bfd_link_order *link_order ATTRIBUTE_UNUSED,
3440      bfd_byte *data ATTRIBUTE_UNUSED,
3441      bfd_boolean relocatable ATTRIBUTE_UNUSED,
3442      asymbol **symbols ATTRIBUTE_UNUSED)
3443 {
3444   return (bfd_byte *) _bfd_ptr_bfd_null_error (abfd);
3445 }
3446 
3447 bfd_boolean
3448 _bfd_nolink_bfd_lookup_section_flags
3449     (struct bfd_link_info *info ATTRIBUTE_UNUSED,
3450      struct flag_info *flaginfo ATTRIBUTE_UNUSED,
3451      asection *section)
3452 {
3453   return _bfd_bool_bfd_false_error (section->owner);
3454 }
3455 
3456 bfd_boolean
3457 _bfd_nolink_bfd_is_group_section (bfd *abfd,
3458 				  const asection *sec ATTRIBUTE_UNUSED)
3459 {
3460   return _bfd_bool_bfd_false_error (abfd);
3461 }
3462 
3463 bfd_boolean
3464 _bfd_nolink_bfd_discard_group (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
3465 {
3466   return _bfd_bool_bfd_false_error (abfd);
3467 }
3468 
3469 struct bfd_link_hash_table *
3470 _bfd_nolink_bfd_link_hash_table_create (bfd *abfd)
3471 {
3472   return (struct bfd_link_hash_table *) _bfd_ptr_bfd_null_error (abfd);
3473 }
3474 
3475 void
3476 _bfd_nolink_bfd_link_just_syms (asection *sec ATTRIBUTE_UNUSED,
3477 				struct bfd_link_info *info ATTRIBUTE_UNUSED)
3478 {
3479 }
3480 
3481 void
3482 _bfd_nolink_bfd_copy_link_hash_symbol_type
3483     (bfd *abfd ATTRIBUTE_UNUSED,
3484      struct bfd_link_hash_entry *from ATTRIBUTE_UNUSED,
3485      struct bfd_link_hash_entry *to ATTRIBUTE_UNUSED)
3486 {
3487 }
3488 
3489 bfd_boolean
3490 _bfd_nolink_bfd_link_split_section (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
3491 {
3492   return _bfd_bool_bfd_false_error (abfd);
3493 }
3494 
3495 bfd_boolean
3496 _bfd_nolink_section_already_linked (bfd *abfd,
3497 				    asection *sec ATTRIBUTE_UNUSED,
3498 				    struct bfd_link_info *info ATTRIBUTE_UNUSED)
3499 {
3500   return _bfd_bool_bfd_false_error (abfd);
3501 }
3502 
3503 bfd_boolean
3504 _bfd_nolink_bfd_define_common_symbol
3505     (bfd *abfd,
3506      struct bfd_link_info *info ATTRIBUTE_UNUSED,
3507      struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED)
3508 {
3509   return _bfd_bool_bfd_false_error (abfd);
3510 }
3511 
3512 struct bfd_link_hash_entry *
3513 _bfd_nolink_bfd_define_start_stop (struct bfd_link_info *info ATTRIBUTE_UNUSED,
3514 				   const char *name ATTRIBUTE_UNUSED,
3515 				   asection *sec)
3516 {
3517   return (struct bfd_link_hash_entry *) _bfd_ptr_bfd_null_error (sec->owner);
3518 }
3519