1 /* linker.c -- BFD linker routines 2 Copyright (C) 1993-2022 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 bool generic_link_add_object_symbols 406 (bfd *, struct bfd_link_info *); 407 static bool generic_link_check_archive_element 408 (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *, const char *, 409 bool *); 410 static bool generic_link_add_symbol_list 411 (bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **); 412 static bool generic_add_output_symbol 413 (bfd *, size_t *psymalloc, asymbol *); 414 static bool default_data_link_order 415 (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *); 416 static bool default_indirect_link_order 417 (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *, 418 bool); 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 bool 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 bool 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 bool create, 506 bool copy, 507 bool 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 bool create, 536 bool copy, 537 bool follow) 538 { 539 size_t 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 && startswith (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 if (h != NULL) 603 h->ref_real = 1; 604 free (n); 605 return h; 606 } 607 608 #undef REAL 609 } 610 611 return bfd_link_hash_lookup (info->hash, string, create, copy, follow); 612 } 613 614 /* If H is a wrapped symbol, ie. the symbol name starts with "__wrap_" 615 and the remainder is found in wrap_hash, return the real symbol. */ 616 617 struct bfd_link_hash_entry * 618 unwrap_hash_lookup (struct bfd_link_info *info, 619 bfd *input_bfd, 620 struct bfd_link_hash_entry *h) 621 { 622 const char *l = h->root.string; 623 624 if (*l == bfd_get_symbol_leading_char (input_bfd) 625 || *l == info->wrap_char) 626 ++l; 627 628 if (startswith (l, WRAP)) 629 { 630 l += sizeof WRAP - 1; 631 632 if (bfd_hash_lookup (info->wrap_hash, l, false, false) != NULL) 633 { 634 char save = 0; 635 if (l - (sizeof WRAP - 1) != h->root.string) 636 { 637 --l; 638 save = *l; 639 *(char *) l = *h->root.string; 640 } 641 h = bfd_link_hash_lookup (info->hash, l, false, false, false); 642 if (save) 643 *(char *) l = save; 644 } 645 } 646 return h; 647 } 648 #undef WRAP 649 650 /* Traverse a generic link hash table. Differs from bfd_hash_traverse 651 in the treatment of warning symbols. When warning symbols are 652 created they replace the real symbol, so you don't get to see the 653 real symbol in a bfd_hash_traverse. This traversal calls func with 654 the real symbol. */ 655 656 void 657 bfd_link_hash_traverse 658 (struct bfd_link_hash_table *htab, 659 bool (*func) (struct bfd_link_hash_entry *, void *), 660 void *info) 661 { 662 unsigned int i; 663 664 htab->table.frozen = 1; 665 for (i = 0; i < htab->table.size; i++) 666 { 667 struct bfd_link_hash_entry *p; 668 669 p = (struct bfd_link_hash_entry *) htab->table.table[i]; 670 for (; p != NULL; p = (struct bfd_link_hash_entry *) p->root.next) 671 if (!(*func) (p->type == bfd_link_hash_warning ? p->u.i.link : p, info)) 672 goto out; 673 } 674 out: 675 htab->table.frozen = 0; 676 } 677 678 /* Add a symbol to the linker hash table undefs list. */ 679 680 void 681 bfd_link_add_undef (struct bfd_link_hash_table *table, 682 struct bfd_link_hash_entry *h) 683 { 684 BFD_ASSERT (h->u.undef.next == NULL); 685 if (table->undefs_tail != NULL) 686 table->undefs_tail->u.undef.next = h; 687 if (table->undefs == NULL) 688 table->undefs = h; 689 table->undefs_tail = h; 690 } 691 692 /* The undefs list was designed so that in normal use we don't need to 693 remove entries. However, if symbols on the list are changed from 694 bfd_link_hash_undefined to either bfd_link_hash_undefweak or 695 bfd_link_hash_new for some reason, then they must be removed from the 696 list. Failure to do so might result in the linker attempting to add 697 the symbol to the list again at a later stage. */ 698 699 void 700 bfd_link_repair_undef_list (struct bfd_link_hash_table *table) 701 { 702 struct bfd_link_hash_entry **pun; 703 704 pun = &table->undefs; 705 while (*pun != NULL) 706 { 707 struct bfd_link_hash_entry *h = *pun; 708 709 if (h->type == bfd_link_hash_new 710 || h->type == bfd_link_hash_undefweak) 711 { 712 *pun = h->u.undef.next; 713 h->u.undef.next = NULL; 714 if (h == table->undefs_tail) 715 { 716 if (pun == &table->undefs) 717 table->undefs_tail = NULL; 718 else 719 /* pun points at an u.undef.next field. Go back to 720 the start of the link_hash_entry. */ 721 table->undefs_tail = (struct bfd_link_hash_entry *) 722 ((char *) pun - ((char *) &h->u.undef.next - (char *) h)); 723 break; 724 } 725 } 726 else 727 pun = &h->u.undef.next; 728 } 729 } 730 731 /* Routine to create an entry in a generic link hash table. */ 732 733 struct bfd_hash_entry * 734 _bfd_generic_link_hash_newfunc (struct bfd_hash_entry *entry, 735 struct bfd_hash_table *table, 736 const char *string) 737 { 738 /* Allocate the structure if it has not already been allocated by a 739 subclass. */ 740 if (entry == NULL) 741 { 742 entry = (struct bfd_hash_entry *) 743 bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry)); 744 if (entry == NULL) 745 return entry; 746 } 747 748 /* Call the allocation method of the superclass. */ 749 entry = _bfd_link_hash_newfunc (entry, table, string); 750 if (entry) 751 { 752 struct generic_link_hash_entry *ret; 753 754 /* Set local fields. */ 755 ret = (struct generic_link_hash_entry *) entry; 756 ret->written = false; 757 ret->sym = NULL; 758 } 759 760 return entry; 761 } 762 763 /* Create a generic link hash table. */ 764 765 struct bfd_link_hash_table * 766 _bfd_generic_link_hash_table_create (bfd *abfd) 767 { 768 struct generic_link_hash_table *ret; 769 size_t amt = sizeof (struct generic_link_hash_table); 770 771 ret = (struct generic_link_hash_table *) bfd_malloc (amt); 772 if (ret == NULL) 773 return NULL; 774 if (! _bfd_link_hash_table_init (&ret->root, abfd, 775 _bfd_generic_link_hash_newfunc, 776 sizeof (struct generic_link_hash_entry))) 777 { 778 free (ret); 779 return NULL; 780 } 781 return &ret->root; 782 } 783 784 void 785 _bfd_generic_link_hash_table_free (bfd *obfd) 786 { 787 struct generic_link_hash_table *ret; 788 789 BFD_ASSERT (obfd->is_linker_output && obfd->link.hash); 790 ret = (struct generic_link_hash_table *) obfd->link.hash; 791 bfd_hash_table_free (&ret->root.table); 792 free (ret); 793 obfd->link.hash = NULL; 794 obfd->is_linker_output = false; 795 } 796 797 /* Grab the symbols for an object file when doing a generic link. We 798 store the symbols in the outsymbols field. We need to keep them 799 around for the entire link to ensure that we only read them once. 800 If we read them multiple times, we might wind up with relocs and 801 the hash table pointing to different instances of the symbol 802 structure. */ 803 804 bool 805 bfd_generic_link_read_symbols (bfd *abfd) 806 { 807 if (bfd_get_outsymbols (abfd) == NULL) 808 { 809 long symsize; 810 long symcount; 811 812 symsize = bfd_get_symtab_upper_bound (abfd); 813 if (symsize < 0) 814 return false; 815 abfd->outsymbols = bfd_alloc (abfd, symsize); 816 if (bfd_get_outsymbols (abfd) == NULL && symsize != 0) 817 return false; 818 symcount = bfd_canonicalize_symtab (abfd, bfd_get_outsymbols (abfd)); 819 if (symcount < 0) 820 return false; 821 abfd->symcount = symcount; 822 } 823 824 return true; 825 } 826 827 /* Indicate that we are only retrieving symbol values from this 828 section. We want the symbols to act as though the values in the 829 file are absolute. */ 830 831 void 832 _bfd_generic_link_just_syms (asection *sec, 833 struct bfd_link_info *info ATTRIBUTE_UNUSED) 834 { 835 sec->sec_info_type = SEC_INFO_TYPE_JUST_SYMS; 836 sec->output_section = bfd_abs_section_ptr; 837 sec->output_offset = sec->vma; 838 } 839 840 /* Copy the symbol type and other attributes for a linker script 841 assignment from HSRC to HDEST. 842 The default implementation does nothing. */ 843 void 844 _bfd_generic_copy_link_hash_symbol_type (bfd *abfd ATTRIBUTE_UNUSED, 845 struct bfd_link_hash_entry *hdest ATTRIBUTE_UNUSED, 846 struct bfd_link_hash_entry *hsrc ATTRIBUTE_UNUSED) 847 { 848 } 849 850 /* Generic function to add symbols from an object file to the 851 global hash table. */ 852 853 bool 854 _bfd_generic_link_add_symbols (bfd *abfd, struct bfd_link_info *info) 855 { 856 bool ret; 857 858 switch (bfd_get_format (abfd)) 859 { 860 case bfd_object: 861 ret = generic_link_add_object_symbols (abfd, info); 862 break; 863 case bfd_archive: 864 ret = (_bfd_generic_link_add_archive_symbols 865 (abfd, info, generic_link_check_archive_element)); 866 break; 867 default: 868 bfd_set_error (bfd_error_wrong_format); 869 ret = false; 870 } 871 872 return ret; 873 } 874 875 /* Add symbols from an object file to the global hash table. */ 876 877 static bool 878 generic_link_add_object_symbols (bfd *abfd, 879 struct bfd_link_info *info) 880 { 881 bfd_size_type symcount; 882 struct bfd_symbol **outsyms; 883 884 if (!bfd_generic_link_read_symbols (abfd)) 885 return false; 886 symcount = _bfd_generic_link_get_symcount (abfd); 887 outsyms = _bfd_generic_link_get_symbols (abfd); 888 return generic_link_add_symbol_list (abfd, info, symcount, outsyms); 889 } 890 891 /* Generic function to add symbols from an archive file to the global 892 hash file. This function presumes that the archive symbol table 893 has already been read in (this is normally done by the 894 bfd_check_format entry point). It looks through the archive symbol 895 table for symbols that are undefined or common in the linker global 896 symbol hash table. When one is found, the CHECKFN argument is used 897 to see if an object file should be included. This allows targets 898 to customize common symbol behaviour. CHECKFN should set *PNEEDED 899 to TRUE if the object file should be included, and must also call 900 the bfd_link_info add_archive_element callback function and handle 901 adding the symbols to the global hash table. CHECKFN must notice 902 if the callback indicates a substitute BFD, and arrange to add 903 those symbols instead if it does so. CHECKFN should only return 904 FALSE if some sort of error occurs. */ 905 906 bool 907 _bfd_generic_link_add_archive_symbols 908 (bfd *abfd, 909 struct bfd_link_info *info, 910 bool (*checkfn) (bfd *, struct bfd_link_info *, 911 struct bfd_link_hash_entry *, const char *, bool *)) 912 { 913 bool 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 bool 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 && startswith (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 info); 988 if (element == NULL 989 || !bfd_check_format (element, bfd_object)) 990 goto error_return; 991 } 992 993 undefs_tail = info->hash->undefs_tail; 994 995 /* CHECKFN will see if this element should be included, and 996 go ahead and include it if appropriate. */ 997 if (! (*checkfn) (element, info, h, arsym->name, &needed)) 998 goto error_return; 999 1000 if (needed) 1001 { 1002 unsigned int mark; 1003 1004 /* Look backward to mark all symbols from this object file 1005 which we have already seen in this pass. */ 1006 mark = indx; 1007 do 1008 { 1009 included[mark] = 1; 1010 if (mark == 0) 1011 break; 1012 --mark; 1013 } 1014 while (arsyms[mark].file_offset == last_ar_offset); 1015 1016 if (undefs_tail != info->hash->undefs_tail) 1017 loop = true; 1018 } 1019 } 1020 } while (loop); 1021 1022 free (included); 1023 return true; 1024 1025 error_return: 1026 free (included); 1027 return false; 1028 } 1029 1030 /* See if we should include an archive element. */ 1031 1032 static bool 1033 generic_link_check_archive_element (bfd *abfd, 1034 struct bfd_link_info *info, 1035 struct bfd_link_hash_entry *h, 1036 const char *name ATTRIBUTE_UNUSED, 1037 bool *pneeded) 1038 { 1039 asymbol **pp, **ppend; 1040 1041 *pneeded = false; 1042 1043 if (!bfd_generic_link_read_symbols (abfd)) 1044 return false; 1045 1046 pp = _bfd_generic_link_get_symbols (abfd); 1047 ppend = pp + _bfd_generic_link_get_symcount (abfd); 1048 for (; pp < ppend; pp++) 1049 { 1050 asymbol *p; 1051 1052 p = *pp; 1053 1054 /* We are only interested in globally visible symbols. */ 1055 if (! bfd_is_com_section (p->section) 1056 && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0) 1057 continue; 1058 1059 /* We are only interested if we know something about this 1060 symbol, and it is undefined or common. An undefined weak 1061 symbol (type bfd_link_hash_undefweak) is not considered to be 1062 a reference when pulling files out of an archive. See the 1063 SVR4 ABI, p. 4-27. */ 1064 h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), false, 1065 false, true); 1066 if (h == NULL 1067 || (h->type != bfd_link_hash_undefined 1068 && h->type != bfd_link_hash_common)) 1069 continue; 1070 1071 /* P is a symbol we are looking for. */ 1072 1073 if (! bfd_is_com_section (p->section) 1074 || (h->type == bfd_link_hash_undefined 1075 && h->u.undef.abfd == NULL)) 1076 { 1077 /* P is not a common symbol, or an undefined reference was 1078 created from outside BFD such as from a linker -u option. 1079 This object file defines the symbol, so pull it in. */ 1080 *pneeded = true; 1081 if (!(*info->callbacks 1082 ->add_archive_element) (info, abfd, bfd_asymbol_name (p), 1083 &abfd)) 1084 return false; 1085 /* Potentially, the add_archive_element hook may have set a 1086 substitute BFD for us. */ 1087 return bfd_link_add_symbols (abfd, info); 1088 } 1089 1090 /* P is a common symbol. */ 1091 1092 if (h->type == bfd_link_hash_undefined) 1093 { 1094 bfd *symbfd; 1095 bfd_vma size; 1096 unsigned int power; 1097 1098 /* Turn the symbol into a common symbol but do not link in 1099 the object file. This is how a.out works. Object 1100 formats that require different semantics must implement 1101 this function differently. This symbol is already on the 1102 undefs list. We add the section to a common section 1103 attached to symbfd to ensure that it is in a BFD which 1104 will be linked in. */ 1105 symbfd = h->u.undef.abfd; 1106 h->type = bfd_link_hash_common; 1107 h->u.c.p = (struct bfd_link_hash_common_entry *) 1108 bfd_hash_allocate (&info->hash->table, 1109 sizeof (struct bfd_link_hash_common_entry)); 1110 if (h->u.c.p == NULL) 1111 return false; 1112 1113 size = bfd_asymbol_value (p); 1114 h->u.c.size = size; 1115 1116 power = bfd_log2 (size); 1117 if (power > 4) 1118 power = 4; 1119 h->u.c.p->alignment_power = power; 1120 1121 if (p->section == bfd_com_section_ptr) 1122 h->u.c.p->section = bfd_make_section_old_way (symbfd, "COMMON"); 1123 else 1124 h->u.c.p->section = bfd_make_section_old_way (symbfd, 1125 p->section->name); 1126 h->u.c.p->section->flags |= SEC_ALLOC; 1127 } 1128 else 1129 { 1130 /* Adjust the size of the common symbol if necessary. This 1131 is how a.out works. Object formats that require 1132 different semantics must implement this function 1133 differently. */ 1134 if (bfd_asymbol_value (p) > h->u.c.size) 1135 h->u.c.size = bfd_asymbol_value (p); 1136 } 1137 } 1138 1139 /* This archive element is not needed. */ 1140 return true; 1141 } 1142 1143 /* Add the symbols from an object file to the global hash table. ABFD 1144 is the object file. INFO is the linker information. SYMBOL_COUNT 1145 is the number of symbols. SYMBOLS is the list of symbols. */ 1146 1147 static bool 1148 generic_link_add_symbol_list (bfd *abfd, 1149 struct bfd_link_info *info, 1150 bfd_size_type symbol_count, 1151 asymbol **symbols) 1152 { 1153 asymbol **pp, **ppend; 1154 1155 pp = symbols; 1156 ppend = symbols + symbol_count; 1157 for (; pp < ppend; pp++) 1158 { 1159 asymbol *p; 1160 1161 p = *pp; 1162 1163 if ((p->flags & (BSF_INDIRECT 1164 | BSF_WARNING 1165 | BSF_GLOBAL 1166 | BSF_CONSTRUCTOR 1167 | BSF_WEAK)) != 0 1168 || bfd_is_und_section (bfd_asymbol_section (p)) 1169 || bfd_is_com_section (bfd_asymbol_section (p)) 1170 || bfd_is_ind_section (bfd_asymbol_section (p))) 1171 { 1172 const char *name; 1173 const char *string; 1174 struct generic_link_hash_entry *h; 1175 struct bfd_link_hash_entry *bh; 1176 1177 string = name = bfd_asymbol_name (p); 1178 if (((p->flags & BSF_INDIRECT) != 0 1179 || bfd_is_ind_section (p->section)) 1180 && pp + 1 < ppend) 1181 { 1182 pp++; 1183 string = bfd_asymbol_name (*pp); 1184 } 1185 else if ((p->flags & BSF_WARNING) != 0 1186 && pp + 1 < ppend) 1187 { 1188 /* The name of P is actually the warning string, and the 1189 next symbol is the one to warn about. */ 1190 pp++; 1191 name = bfd_asymbol_name (*pp); 1192 } 1193 1194 bh = NULL; 1195 if (! (_bfd_generic_link_add_one_symbol 1196 (info, abfd, name, p->flags, bfd_asymbol_section (p), 1197 p->value, string, false, false, &bh))) 1198 return false; 1199 h = (struct generic_link_hash_entry *) bh; 1200 1201 /* If this is a constructor symbol, and the linker didn't do 1202 anything with it, then we want to just pass the symbol 1203 through to the output file. This will happen when 1204 linking with -r. */ 1205 if ((p->flags & BSF_CONSTRUCTOR) != 0 1206 && (h == NULL || h->root.type == bfd_link_hash_new)) 1207 { 1208 p->udata.p = NULL; 1209 continue; 1210 } 1211 1212 /* Save the BFD symbol so that we don't lose any backend 1213 specific information that may be attached to it. We only 1214 want this one if it gives more information than the 1215 existing one; we don't want to replace a defined symbol 1216 with an undefined one. This routine may be called with a 1217 hash table other than the generic hash table, so we only 1218 do this if we are certain that the hash table is a 1219 generic one. */ 1220 if (info->output_bfd->xvec == abfd->xvec) 1221 { 1222 if (h->sym == NULL 1223 || (! bfd_is_und_section (bfd_asymbol_section (p)) 1224 && (! bfd_is_com_section (bfd_asymbol_section (p)) 1225 || bfd_is_und_section (bfd_asymbol_section (h->sym))))) 1226 { 1227 h->sym = p; 1228 /* BSF_OLD_COMMON is a hack to support COFF reloc 1229 reading, and it should go away when the COFF 1230 linker is switched to the new version. */ 1231 if (bfd_is_com_section (bfd_asymbol_section (p))) 1232 p->flags |= BSF_OLD_COMMON; 1233 } 1234 } 1235 1236 /* Store a back pointer from the symbol to the hash 1237 table entry for the benefit of relaxation code until 1238 it gets rewritten to not use asymbol structures. 1239 Setting this is also used to check whether these 1240 symbols were set up by the generic linker. */ 1241 p->udata.p = h; 1242 } 1243 } 1244 1245 return true; 1246 } 1247 1248 /* We use a state table to deal with adding symbols from an object 1249 file. The first index into the state table describes the symbol 1250 from the object file. The second index into the state table is the 1251 type of the symbol in the hash table. */ 1252 1253 /* The symbol from the object file is turned into one of these row 1254 values. */ 1255 1256 enum link_row 1257 { 1258 UNDEF_ROW, /* Undefined. */ 1259 UNDEFW_ROW, /* Weak undefined. */ 1260 DEF_ROW, /* Defined. */ 1261 DEFW_ROW, /* Weak defined. */ 1262 COMMON_ROW, /* Common. */ 1263 INDR_ROW, /* Indirect. */ 1264 WARN_ROW, /* Warning. */ 1265 SET_ROW /* Member of set. */ 1266 }; 1267 1268 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */ 1269 #undef FAIL 1270 1271 /* The actions to take in the state table. */ 1272 1273 enum link_action 1274 { 1275 FAIL, /* Abort. */ 1276 UND, /* Mark symbol undefined. */ 1277 WEAK, /* Mark symbol weak undefined. */ 1278 DEF, /* Mark symbol defined. */ 1279 DEFW, /* Mark symbol weak defined. */ 1280 COM, /* Mark symbol common. */ 1281 REF, /* Mark defined symbol referenced. */ 1282 CREF, /* Possibly warn about common reference to defined symbol. */ 1283 CDEF, /* Define existing common symbol. */ 1284 NOACT, /* No action. */ 1285 BIG, /* Mark symbol common using largest size. */ 1286 MDEF, /* Multiple definition error. */ 1287 MIND, /* Multiple indirect symbols. */ 1288 IND, /* Make indirect symbol. */ 1289 CIND, /* Make indirect symbol from existing common symbol. */ 1290 SET, /* Add value to set. */ 1291 MWARN, /* Make warning symbol. */ 1292 WARN, /* Warn if referenced, else MWARN. */ 1293 CYCLE, /* Repeat with symbol pointed to. */ 1294 REFC, /* Mark indirect symbol referenced and then CYCLE. */ 1295 WARNC /* Issue warning and then CYCLE. */ 1296 }; 1297 1298 /* The state table itself. The first index is a link_row and the 1299 second index is a bfd_link_hash_type. */ 1300 1301 static const enum link_action link_action[8][8] = 1302 { 1303 /* current\prev new undef undefw def defw com indr warn */ 1304 /* UNDEF_ROW */ {UND, NOACT, UND, REF, REF, NOACT, REFC, WARNC }, 1305 /* UNDEFW_ROW */ {WEAK, NOACT, NOACT, REF, REF, NOACT, REFC, WARNC }, 1306 /* DEF_ROW */ {DEF, DEF, DEF, MDEF, DEF, CDEF, MIND, CYCLE }, 1307 /* DEFW_ROW */ {DEFW, DEFW, DEFW, NOACT, NOACT, NOACT, NOACT, CYCLE }, 1308 /* COMMON_ROW */ {COM, COM, COM, CREF, COM, BIG, REFC, WARNC }, 1309 /* INDR_ROW */ {IND, IND, IND, MDEF, IND, CIND, MIND, CYCLE }, 1310 /* WARN_ROW */ {MWARN, WARN, WARN, WARN, WARN, WARN, WARN, NOACT }, 1311 /* SET_ROW */ {SET, SET, SET, SET, SET, SET, CYCLE, CYCLE } 1312 }; 1313 1314 /* Most of the entries in the LINK_ACTION table are straightforward, 1315 but a few are somewhat subtle. 1316 1317 A reference to an indirect symbol (UNDEF_ROW/indr or 1318 UNDEFW_ROW/indr) is counted as a reference both to the indirect 1319 symbol and to the symbol the indirect symbol points to. 1320 1321 A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn) 1322 causes the warning to be issued. 1323 1324 A common definition of an indirect symbol (COMMON_ROW/indr) is 1325 treated as a multiple definition error. Likewise for an indirect 1326 definition of a common symbol (INDR_ROW/com). 1327 1328 An indirect definition of a warning (INDR_ROW/warn) does not cause 1329 the warning to be issued. 1330 1331 If a warning is created for an indirect symbol (WARN_ROW/indr) no 1332 warning is created for the symbol the indirect symbol points to. 1333 1334 Adding an entry to a set does not count as a reference to a set, 1335 and no warning is issued (SET_ROW/warn). */ 1336 1337 /* Return the BFD in which a hash entry has been defined, if known. */ 1338 1339 static bfd * 1340 hash_entry_bfd (struct bfd_link_hash_entry *h) 1341 { 1342 while (h->type == bfd_link_hash_warning) 1343 h = h->u.i.link; 1344 switch (h->type) 1345 { 1346 default: 1347 return NULL; 1348 case bfd_link_hash_undefined: 1349 case bfd_link_hash_undefweak: 1350 return h->u.undef.abfd; 1351 case bfd_link_hash_defined: 1352 case bfd_link_hash_defweak: 1353 return h->u.def.section->owner; 1354 case bfd_link_hash_common: 1355 return h->u.c.p->section->owner; 1356 } 1357 /*NOTREACHED*/ 1358 } 1359 1360 /* Add a symbol to the global hash table. 1361 ABFD is the BFD the symbol comes from. 1362 NAME is the name of the symbol. 1363 FLAGS is the BSF_* bits associated with the symbol. 1364 SECTION is the section in which the symbol is defined; this may be 1365 bfd_und_section_ptr or bfd_com_section_ptr. 1366 VALUE is the value of the symbol, relative to the section. 1367 STRING is used for either an indirect symbol, in which case it is 1368 the name of the symbol to indirect to, or a warning symbol, in 1369 which case it is the warning string. 1370 COPY is TRUE if NAME or STRING must be copied into locally 1371 allocated memory if they need to be saved. 1372 COLLECT is TRUE if we should automatically collect gcc constructor 1373 or destructor names as collect2 does. 1374 HASHP, if not NULL, is a place to store the created hash table 1375 entry; if *HASHP is not NULL, the caller has already looked up 1376 the hash table entry, and stored it in *HASHP. */ 1377 1378 bool 1379 _bfd_generic_link_add_one_symbol (struct bfd_link_info *info, 1380 bfd *abfd, 1381 const char *name, 1382 flagword flags, 1383 asection *section, 1384 bfd_vma value, 1385 const char *string, 1386 bool copy, 1387 bool collect, 1388 struct bfd_link_hash_entry **hashp) 1389 { 1390 enum link_row row; 1391 struct bfd_link_hash_entry *h; 1392 struct bfd_link_hash_entry *inh = NULL; 1393 bool cycle; 1394 1395 BFD_ASSERT (section != NULL); 1396 1397 if (bfd_is_ind_section (section) 1398 || (flags & BSF_INDIRECT) != 0) 1399 { 1400 row = INDR_ROW; 1401 /* Create the indirect symbol here. This is for the benefit of 1402 the plugin "notice" function. 1403 STRING is the name of the symbol we want to indirect to. */ 1404 inh = bfd_wrapped_link_hash_lookup (abfd, info, string, true, 1405 copy, false); 1406 if (inh == NULL) 1407 return false; 1408 } 1409 else if ((flags & BSF_WARNING) != 0) 1410 row = WARN_ROW; 1411 else if ((flags & BSF_CONSTRUCTOR) != 0) 1412 row = SET_ROW; 1413 else if (bfd_is_und_section (section)) 1414 { 1415 if ((flags & BSF_WEAK) != 0) 1416 row = UNDEFW_ROW; 1417 else 1418 row = UNDEF_ROW; 1419 } 1420 else if ((flags & BSF_WEAK) != 0) 1421 row = DEFW_ROW; 1422 else if (bfd_is_com_section (section)) 1423 { 1424 row = COMMON_ROW; 1425 if (!bfd_link_relocatable (info) 1426 && name != NULL 1427 && name[0] == '_' 1428 && name[1] == '_' 1429 && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0) 1430 _bfd_error_handler 1431 (_("%pB: plugin needed to handle lto object"), abfd); 1432 } 1433 else 1434 row = DEF_ROW; 1435 1436 if (hashp != NULL && *hashp != NULL) 1437 h = *hashp; 1438 else 1439 { 1440 if (row == UNDEF_ROW || row == UNDEFW_ROW) 1441 h = bfd_wrapped_link_hash_lookup (abfd, info, name, true, copy, false); 1442 else 1443 h = bfd_link_hash_lookup (info->hash, name, true, copy, false); 1444 if (h == NULL) 1445 { 1446 if (hashp != NULL) 1447 *hashp = NULL; 1448 return false; 1449 } 1450 } 1451 1452 if (info->notice_all 1453 || (info->notice_hash != NULL 1454 && bfd_hash_lookup (info->notice_hash, name, false, false) != NULL)) 1455 { 1456 if (! (*info->callbacks->notice) (info, h, inh, 1457 abfd, section, value, flags)) 1458 return false; 1459 } 1460 1461 if (hashp != NULL) 1462 *hashp = h; 1463 1464 do 1465 { 1466 enum link_action action; 1467 int prev; 1468 1469 prev = h->type; 1470 /* Treat symbols defined by early linker script pass as undefined. */ 1471 if (h->ldscript_def) 1472 prev = bfd_link_hash_undefined; 1473 cycle = false; 1474 action = link_action[(int) row][prev]; 1475 switch (action) 1476 { 1477 case FAIL: 1478 abort (); 1479 1480 case NOACT: 1481 /* Do nothing. */ 1482 break; 1483 1484 case UND: 1485 /* Make a new undefined symbol. */ 1486 h->type = bfd_link_hash_undefined; 1487 h->u.undef.abfd = abfd; 1488 bfd_link_add_undef (info->hash, h); 1489 break; 1490 1491 case WEAK: 1492 /* Make a new weak undefined symbol. */ 1493 h->type = bfd_link_hash_undefweak; 1494 h->u.undef.abfd = abfd; 1495 break; 1496 1497 case CDEF: 1498 /* We have found a definition for a symbol which was 1499 previously common. */ 1500 BFD_ASSERT (h->type == bfd_link_hash_common); 1501 (*info->callbacks->multiple_common) (info, h, abfd, 1502 bfd_link_hash_defined, 0); 1503 /* Fall through. */ 1504 case DEF: 1505 case DEFW: 1506 { 1507 enum bfd_link_hash_type oldtype; 1508 1509 /* Define a symbol. */ 1510 oldtype = h->type; 1511 if (action == DEFW) 1512 h->type = bfd_link_hash_defweak; 1513 else 1514 h->type = bfd_link_hash_defined; 1515 h->u.def.section = section; 1516 h->u.def.value = value; 1517 h->linker_def = 0; 1518 h->ldscript_def = 0; 1519 1520 /* If we have been asked to, we act like collect2 and 1521 identify all functions that might be global 1522 constructors and destructors and pass them up in a 1523 callback. We only do this for certain object file 1524 types, since many object file types can handle this 1525 automatically. */ 1526 if (collect && name[0] == '_') 1527 { 1528 const char *s; 1529 1530 /* A constructor or destructor name starts like this: 1531 _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and 1532 the second are the same character (we accept any 1533 character there, in case a new object file format 1534 comes along with even worse naming restrictions). */ 1535 1536 #define CONS_PREFIX "GLOBAL_" 1537 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1) 1538 1539 s = name + 1; 1540 while (*s == '_') 1541 ++s; 1542 if (s[0] == 'G' && startswith (s, CONS_PREFIX)) 1543 { 1544 char c; 1545 1546 c = s[CONS_PREFIX_LEN + 1]; 1547 if ((c == 'I' || c == 'D') 1548 && s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2]) 1549 { 1550 /* If this is a definition of a symbol which 1551 was previously weakly defined, we are in 1552 trouble. We have already added a 1553 constructor entry for the weak defined 1554 symbol, and now we are trying to add one 1555 for the new symbol. Fortunately, this case 1556 should never arise in practice. */ 1557 if (oldtype == bfd_link_hash_defweak) 1558 abort (); 1559 1560 (*info->callbacks->constructor) (info, c == 'I', 1561 h->root.string, abfd, 1562 section, value); 1563 } 1564 } 1565 } 1566 } 1567 1568 break; 1569 1570 case COM: 1571 /* We have found a common definition for a symbol. */ 1572 if (h->type == bfd_link_hash_new) 1573 bfd_link_add_undef (info->hash, h); 1574 h->type = bfd_link_hash_common; 1575 h->u.c.p = (struct bfd_link_hash_common_entry *) 1576 bfd_hash_allocate (&info->hash->table, 1577 sizeof (struct bfd_link_hash_common_entry)); 1578 if (h->u.c.p == NULL) 1579 return false; 1580 1581 h->u.c.size = value; 1582 1583 /* Select a default alignment based on the size. This may 1584 be overridden by the caller. */ 1585 { 1586 unsigned int power; 1587 1588 power = bfd_log2 (value); 1589 if (power > 4) 1590 power = 4; 1591 h->u.c.p->alignment_power = power; 1592 } 1593 1594 /* The section of a common symbol is only used if the common 1595 symbol is actually allocated. It basically provides a 1596 hook for the linker script to decide which output section 1597 the common symbols should be put in. In most cases, the 1598 section of a common symbol will be bfd_com_section_ptr, 1599 the code here will choose a common symbol section named 1600 "COMMON", and the linker script will contain *(COMMON) in 1601 the appropriate place. A few targets use separate common 1602 sections for small symbols, and they require special 1603 handling. */ 1604 if (section == bfd_com_section_ptr) 1605 { 1606 h->u.c.p->section = bfd_make_section_old_way (abfd, "COMMON"); 1607 h->u.c.p->section->flags |= SEC_ALLOC; 1608 } 1609 else if (section->owner != abfd) 1610 { 1611 h->u.c.p->section = bfd_make_section_old_way (abfd, 1612 section->name); 1613 h->u.c.p->section->flags |= SEC_ALLOC; 1614 } 1615 else 1616 h->u.c.p->section = section; 1617 h->linker_def = 0; 1618 h->ldscript_def = 0; 1619 break; 1620 1621 case REF: 1622 /* A reference to a defined symbol. */ 1623 if (h->u.undef.next == NULL && info->hash->undefs_tail != h) 1624 h->u.undef.next = h; 1625 break; 1626 1627 case BIG: 1628 /* We have found a common definition for a symbol which 1629 already had a common definition. Use the maximum of the 1630 two sizes, and use the section required by the larger symbol. */ 1631 BFD_ASSERT (h->type == bfd_link_hash_common); 1632 (*info->callbacks->multiple_common) (info, h, abfd, 1633 bfd_link_hash_common, value); 1634 if (value > h->u.c.size) 1635 { 1636 unsigned int power; 1637 1638 h->u.c.size = value; 1639 1640 /* Select a default alignment based on the size. This may 1641 be overridden by the caller. */ 1642 power = bfd_log2 (value); 1643 if (power > 4) 1644 power = 4; 1645 h->u.c.p->alignment_power = power; 1646 1647 /* Some systems have special treatment for small commons, 1648 hence we want to select the section used by the larger 1649 symbol. This makes sure the symbol does not go in a 1650 small common section if it is now too large. */ 1651 if (section == bfd_com_section_ptr) 1652 { 1653 h->u.c.p->section 1654 = bfd_make_section_old_way (abfd, "COMMON"); 1655 h->u.c.p->section->flags |= SEC_ALLOC; 1656 } 1657 else if (section->owner != abfd) 1658 { 1659 h->u.c.p->section 1660 = bfd_make_section_old_way (abfd, section->name); 1661 h->u.c.p->section->flags |= SEC_ALLOC; 1662 } 1663 else 1664 h->u.c.p->section = section; 1665 } 1666 break; 1667 1668 case CREF: 1669 /* We have found a common definition for a symbol which 1670 was already defined. */ 1671 (*info->callbacks->multiple_common) (info, h, abfd, 1672 bfd_link_hash_common, value); 1673 break; 1674 1675 case MIND: 1676 /* Multiple indirect symbols. This is OK if they both point 1677 to the same symbol. */ 1678 if (h->u.i.link->type == bfd_link_hash_defweak) 1679 { 1680 /* It is also OK to redefine a symbol that indirects to 1681 a weak definition. So for sym@ver -> sym@@ver where 1682 sym@@ver is weak and we have a new strong sym@ver, 1683 redefine sym@@ver. Of course if there exists 1684 sym -> sym@@ver then this also redefines sym. */ 1685 h = h->u.i.link; 1686 cycle = true; 1687 break; 1688 } 1689 if (string != NULL && strcmp (h->u.i.link->root.string, string) == 0) 1690 break; 1691 /* Fall through. */ 1692 case MDEF: 1693 /* Handle a multiple definition. */ 1694 (*info->callbacks->multiple_definition) (info, h, 1695 abfd, section, value); 1696 break; 1697 1698 case CIND: 1699 /* Create an indirect symbol from an existing common symbol. */ 1700 BFD_ASSERT (h->type == bfd_link_hash_common); 1701 (*info->callbacks->multiple_common) (info, h, abfd, 1702 bfd_link_hash_indirect, 0); 1703 /* Fall through. */ 1704 case IND: 1705 if (inh->type == bfd_link_hash_indirect 1706 && inh->u.i.link == h) 1707 { 1708 _bfd_error_handler 1709 /* xgettext:c-format */ 1710 (_("%pB: indirect symbol `%s' to `%s' is a loop"), 1711 abfd, name, string); 1712 bfd_set_error (bfd_error_invalid_operation); 1713 return false; 1714 } 1715 if (inh->type == bfd_link_hash_new) 1716 { 1717 inh->type = bfd_link_hash_undefined; 1718 inh->u.undef.abfd = abfd; 1719 bfd_link_add_undef (info->hash, inh); 1720 } 1721 1722 /* If the indirect symbol has been referenced, we need to 1723 push the reference down to the symbol we are referencing. */ 1724 if (h->type != bfd_link_hash_new) 1725 { 1726 /* ??? If inh->type == bfd_link_hash_undefweak this 1727 converts inh to bfd_link_hash_undefined. */ 1728 row = UNDEF_ROW; 1729 cycle = true; 1730 } 1731 1732 h->type = bfd_link_hash_indirect; 1733 h->u.i.link = inh; 1734 /* Not setting h = h->u.i.link here means that when cycle is 1735 set above we'll always go to REFC, and then cycle again 1736 to the indirected symbol. This means that any successful 1737 change of an existing symbol to indirect counts as a 1738 reference. ??? That may not be correct when the existing 1739 symbol was defweak. */ 1740 break; 1741 1742 case SET: 1743 /* Add an entry to a set. */ 1744 (*info->callbacks->add_to_set) (info, h, BFD_RELOC_CTOR, 1745 abfd, section, value); 1746 break; 1747 1748 case WARNC: 1749 /* Issue a warning and cycle, except when the reference is 1750 in LTO IR. */ 1751 if (h->u.i.warning != NULL 1752 && (abfd->flags & BFD_PLUGIN) == 0) 1753 { 1754 (*info->callbacks->warning) (info, h->u.i.warning, 1755 h->root.string, abfd, NULL, 0); 1756 /* Only issue a warning once. */ 1757 h->u.i.warning = NULL; 1758 } 1759 /* Fall through. */ 1760 case CYCLE: 1761 /* Try again with the referenced symbol. */ 1762 h = h->u.i.link; 1763 cycle = true; 1764 break; 1765 1766 case REFC: 1767 /* A reference to an indirect symbol. */ 1768 if (h->u.undef.next == NULL && info->hash->undefs_tail != h) 1769 h->u.undef.next = h; 1770 h = h->u.i.link; 1771 cycle = true; 1772 break; 1773 1774 case WARN: 1775 /* Warn if this symbol has been referenced already from non-IR, 1776 otherwise add a warning. */ 1777 if ((!info->lto_plugin_active 1778 && (h->u.undef.next != NULL || info->hash->undefs_tail == h)) 1779 || h->non_ir_ref_regular 1780 || h->non_ir_ref_dynamic) 1781 { 1782 (*info->callbacks->warning) (info, string, h->root.string, 1783 hash_entry_bfd (h), NULL, 0); 1784 break; 1785 } 1786 /* Fall through. */ 1787 case MWARN: 1788 /* Make a warning symbol. */ 1789 { 1790 struct bfd_link_hash_entry *sub; 1791 1792 /* STRING is the warning to give. */ 1793 sub = ((struct bfd_link_hash_entry *) 1794 ((*info->hash->table.newfunc) 1795 (NULL, &info->hash->table, h->root.string))); 1796 if (sub == NULL) 1797 return false; 1798 *sub = *h; 1799 sub->type = bfd_link_hash_warning; 1800 sub->u.i.link = h; 1801 if (! copy) 1802 sub->u.i.warning = string; 1803 else 1804 { 1805 char *w; 1806 size_t len = strlen (string) + 1; 1807 1808 w = (char *) bfd_hash_allocate (&info->hash->table, len); 1809 if (w == NULL) 1810 return false; 1811 memcpy (w, string, len); 1812 sub->u.i.warning = w; 1813 } 1814 1815 bfd_hash_replace (&info->hash->table, 1816 (struct bfd_hash_entry *) h, 1817 (struct bfd_hash_entry *) sub); 1818 if (hashp != NULL) 1819 *hashp = sub; 1820 } 1821 break; 1822 } 1823 } 1824 while (cycle); 1825 1826 return true; 1827 } 1828 1829 /* Generic final link routine. */ 1830 1831 bool 1832 _bfd_generic_final_link (bfd *abfd, struct bfd_link_info *info) 1833 { 1834 bfd *sub; 1835 asection *o; 1836 struct bfd_link_order *p; 1837 size_t outsymalloc; 1838 struct generic_write_global_symbol_info wginfo; 1839 1840 abfd->outsymbols = NULL; 1841 abfd->symcount = 0; 1842 outsymalloc = 0; 1843 1844 /* Mark all sections which will be included in the output file. */ 1845 for (o = abfd->sections; o != NULL; o = o->next) 1846 for (p = o->map_head.link_order; p != NULL; p = p->next) 1847 if (p->type == bfd_indirect_link_order) 1848 p->u.indirect.section->linker_mark = true; 1849 1850 /* Build the output symbol table. */ 1851 for (sub = info->input_bfds; sub != NULL; sub = sub->link.next) 1852 if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc)) 1853 return false; 1854 1855 /* Accumulate the global symbols. */ 1856 wginfo.info = info; 1857 wginfo.output_bfd = abfd; 1858 wginfo.psymalloc = &outsymalloc; 1859 _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info), 1860 _bfd_generic_link_write_global_symbol, 1861 &wginfo); 1862 1863 /* Make sure we have a trailing NULL pointer on OUTSYMBOLS. We 1864 shouldn't really need one, since we have SYMCOUNT, but some old 1865 code still expects one. */ 1866 if (! generic_add_output_symbol (abfd, &outsymalloc, NULL)) 1867 return false; 1868 1869 if (bfd_link_relocatable (info)) 1870 { 1871 /* Allocate space for the output relocs for each section. */ 1872 for (o = abfd->sections; o != NULL; o = o->next) 1873 { 1874 o->reloc_count = 0; 1875 for (p = o->map_head.link_order; p != NULL; p = p->next) 1876 { 1877 if (p->type == bfd_section_reloc_link_order 1878 || p->type == bfd_symbol_reloc_link_order) 1879 ++o->reloc_count; 1880 else if (p->type == bfd_indirect_link_order) 1881 { 1882 asection *input_section; 1883 bfd *input_bfd; 1884 long relsize; 1885 arelent **relocs; 1886 asymbol **symbols; 1887 long reloc_count; 1888 1889 input_section = p->u.indirect.section; 1890 input_bfd = input_section->owner; 1891 relsize = bfd_get_reloc_upper_bound (input_bfd, 1892 input_section); 1893 if (relsize < 0) 1894 return false; 1895 relocs = (arelent **) bfd_malloc (relsize); 1896 if (!relocs && relsize != 0) 1897 return false; 1898 symbols = _bfd_generic_link_get_symbols (input_bfd); 1899 reloc_count = bfd_canonicalize_reloc (input_bfd, 1900 input_section, 1901 relocs, 1902 symbols); 1903 free (relocs); 1904 if (reloc_count < 0) 1905 return false; 1906 BFD_ASSERT ((unsigned long) reloc_count 1907 == input_section->reloc_count); 1908 o->reloc_count += reloc_count; 1909 } 1910 } 1911 if (o->reloc_count > 0) 1912 { 1913 bfd_size_type amt; 1914 1915 amt = o->reloc_count; 1916 amt *= sizeof (arelent *); 1917 o->orelocation = (struct reloc_cache_entry **) bfd_alloc (abfd, amt); 1918 if (!o->orelocation) 1919 return false; 1920 o->flags |= SEC_RELOC; 1921 /* Reset the count so that it can be used as an index 1922 when putting in the output relocs. */ 1923 o->reloc_count = 0; 1924 } 1925 } 1926 } 1927 1928 /* Handle all the link order information for the sections. */ 1929 for (o = abfd->sections; o != NULL; o = o->next) 1930 { 1931 for (p = o->map_head.link_order; p != NULL; p = p->next) 1932 { 1933 switch (p->type) 1934 { 1935 case bfd_section_reloc_link_order: 1936 case bfd_symbol_reloc_link_order: 1937 if (! _bfd_generic_reloc_link_order (abfd, info, o, p)) 1938 return false; 1939 break; 1940 case bfd_indirect_link_order: 1941 if (! default_indirect_link_order (abfd, info, o, p, true)) 1942 return false; 1943 break; 1944 default: 1945 if (! _bfd_default_link_order (abfd, info, o, p)) 1946 return false; 1947 break; 1948 } 1949 } 1950 } 1951 1952 return true; 1953 } 1954 1955 /* Add an output symbol to the output BFD. */ 1956 1957 static bool 1958 generic_add_output_symbol (bfd *output_bfd, size_t *psymalloc, asymbol *sym) 1959 { 1960 if (bfd_get_symcount (output_bfd) >= *psymalloc) 1961 { 1962 asymbol **newsyms; 1963 bfd_size_type amt; 1964 1965 if (*psymalloc == 0) 1966 *psymalloc = 124; 1967 else 1968 *psymalloc *= 2; 1969 amt = *psymalloc; 1970 amt *= sizeof (asymbol *); 1971 newsyms = (asymbol **) bfd_realloc (bfd_get_outsymbols (output_bfd), amt); 1972 if (newsyms == NULL) 1973 return false; 1974 output_bfd->outsymbols = newsyms; 1975 } 1976 1977 output_bfd->outsymbols[output_bfd->symcount] = sym; 1978 if (sym != NULL) 1979 ++output_bfd->symcount; 1980 1981 return true; 1982 } 1983 1984 /* Handle the symbols for an input BFD. */ 1985 1986 bool 1987 _bfd_generic_link_output_symbols (bfd *output_bfd, 1988 bfd *input_bfd, 1989 struct bfd_link_info *info, 1990 size_t *psymalloc) 1991 { 1992 asymbol **sym_ptr; 1993 asymbol **sym_end; 1994 1995 if (!bfd_generic_link_read_symbols (input_bfd)) 1996 return false; 1997 1998 /* Create a filename symbol if we are supposed to. */ 1999 if (info->create_object_symbols_section != NULL) 2000 { 2001 asection *sec; 2002 2003 for (sec = input_bfd->sections; sec != NULL; sec = sec->next) 2004 { 2005 if (sec->output_section == info->create_object_symbols_section) 2006 { 2007 asymbol *newsym; 2008 2009 newsym = bfd_make_empty_symbol (input_bfd); 2010 if (!newsym) 2011 return false; 2012 newsym->name = bfd_get_filename (input_bfd); 2013 newsym->value = 0; 2014 newsym->flags = BSF_LOCAL | BSF_FILE; 2015 newsym->section = sec; 2016 2017 if (! generic_add_output_symbol (output_bfd, psymalloc, 2018 newsym)) 2019 return false; 2020 2021 break; 2022 } 2023 } 2024 } 2025 2026 /* Adjust the values of the globally visible symbols, and write out 2027 local symbols. */ 2028 sym_ptr = _bfd_generic_link_get_symbols (input_bfd); 2029 sym_end = sym_ptr + _bfd_generic_link_get_symcount (input_bfd); 2030 for (; sym_ptr < sym_end; sym_ptr++) 2031 { 2032 asymbol *sym; 2033 struct generic_link_hash_entry *h; 2034 bool output; 2035 2036 h = NULL; 2037 sym = *sym_ptr; 2038 if ((sym->flags & (BSF_INDIRECT 2039 | BSF_WARNING 2040 | BSF_GLOBAL 2041 | BSF_CONSTRUCTOR 2042 | BSF_WEAK)) != 0 2043 || bfd_is_und_section (bfd_asymbol_section (sym)) 2044 || bfd_is_com_section (bfd_asymbol_section (sym)) 2045 || bfd_is_ind_section (bfd_asymbol_section (sym))) 2046 { 2047 if (sym->udata.p != NULL) 2048 h = (struct generic_link_hash_entry *) sym->udata.p; 2049 else if ((sym->flags & BSF_CONSTRUCTOR) != 0) 2050 { 2051 /* This case normally means that the main linker code 2052 deliberately ignored this constructor symbol. We 2053 should just pass it through. This will screw up if 2054 the constructor symbol is from a different, 2055 non-generic, object file format, but the case will 2056 only arise when linking with -r, which will probably 2057 fail anyhow, since there will be no way to represent 2058 the relocs in the output format being used. */ 2059 h = NULL; 2060 } 2061 else if (bfd_is_und_section (bfd_asymbol_section (sym))) 2062 h = ((struct generic_link_hash_entry *) 2063 bfd_wrapped_link_hash_lookup (output_bfd, info, 2064 bfd_asymbol_name (sym), 2065 false, false, true)); 2066 else 2067 h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info), 2068 bfd_asymbol_name (sym), 2069 false, false, true); 2070 2071 if (h != NULL) 2072 { 2073 /* Force all references to this symbol to point to 2074 the same area in memory. It is possible that 2075 this routine will be called with a hash table 2076 other than a generic hash table, so we double 2077 check that. */ 2078 if (info->output_bfd->xvec == input_bfd->xvec) 2079 { 2080 if (h->sym != NULL) 2081 *sym_ptr = sym = h->sym; 2082 } 2083 2084 switch (h->root.type) 2085 { 2086 default: 2087 case bfd_link_hash_new: 2088 abort (); 2089 case bfd_link_hash_undefined: 2090 break; 2091 case bfd_link_hash_undefweak: 2092 sym->flags |= BSF_WEAK; 2093 break; 2094 case bfd_link_hash_indirect: 2095 h = (struct generic_link_hash_entry *) h->root.u.i.link; 2096 /* fall through */ 2097 case bfd_link_hash_defined: 2098 sym->flags |= BSF_GLOBAL; 2099 sym->flags &=~ (BSF_WEAK | BSF_CONSTRUCTOR); 2100 sym->value = h->root.u.def.value; 2101 sym->section = h->root.u.def.section; 2102 break; 2103 case bfd_link_hash_defweak: 2104 sym->flags |= BSF_WEAK; 2105 sym->flags &=~ BSF_CONSTRUCTOR; 2106 sym->value = h->root.u.def.value; 2107 sym->section = h->root.u.def.section; 2108 break; 2109 case bfd_link_hash_common: 2110 sym->value = h->root.u.c.size; 2111 sym->flags |= BSF_GLOBAL; 2112 if (! bfd_is_com_section (sym->section)) 2113 { 2114 BFD_ASSERT (bfd_is_und_section (sym->section)); 2115 sym->section = bfd_com_section_ptr; 2116 } 2117 /* We do not set the section of the symbol to 2118 h->root.u.c.p->section. That value was saved so 2119 that we would know where to allocate the symbol 2120 if it was defined. In this case the type is 2121 still bfd_link_hash_common, so we did not define 2122 it, so we do not want to use that section. */ 2123 break; 2124 } 2125 } 2126 } 2127 2128 if ((sym->flags & BSF_KEEP) == 0 2129 && (info->strip == strip_all 2130 || (info->strip == strip_some 2131 && bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym), 2132 false, false) == NULL))) 2133 output = false; 2134 else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE)) != 0) 2135 { 2136 /* If this symbol is marked as occurring now, rather 2137 than at the end, output it now. This is used for 2138 COFF C_EXT FCN symbols. FIXME: There must be a 2139 better way. */ 2140 if (bfd_asymbol_bfd (sym) == input_bfd 2141 && (sym->flags & BSF_NOT_AT_END) != 0) 2142 output = true; 2143 else 2144 output = false; 2145 } 2146 else if ((sym->flags & BSF_KEEP) != 0) 2147 output = true; 2148 else if (bfd_is_ind_section (sym->section)) 2149 output = false; 2150 else if ((sym->flags & BSF_DEBUGGING) != 0) 2151 { 2152 if (info->strip == strip_none) 2153 output = true; 2154 else 2155 output = false; 2156 } 2157 else if (bfd_is_und_section (sym->section) 2158 || bfd_is_com_section (sym->section)) 2159 output = false; 2160 else if ((sym->flags & BSF_LOCAL) != 0) 2161 { 2162 if ((sym->flags & BSF_WARNING) != 0) 2163 output = false; 2164 else 2165 { 2166 switch (info->discard) 2167 { 2168 default: 2169 case discard_all: 2170 output = false; 2171 break; 2172 case discard_sec_merge: 2173 output = true; 2174 if (bfd_link_relocatable (info) 2175 || ! (sym->section->flags & SEC_MERGE)) 2176 break; 2177 /* FALLTHROUGH */ 2178 case discard_l: 2179 if (bfd_is_local_label (input_bfd, sym)) 2180 output = false; 2181 else 2182 output = true; 2183 break; 2184 case discard_none: 2185 output = true; 2186 break; 2187 } 2188 } 2189 } 2190 else if ((sym->flags & BSF_CONSTRUCTOR)) 2191 { 2192 if (info->strip != strip_all) 2193 output = true; 2194 else 2195 output = false; 2196 } 2197 else if (sym->flags == 0 2198 && (sym->section->owner->flags & BFD_PLUGIN) != 0) 2199 /* LTO doesn't set symbol information. We get here with the 2200 generic linker for a symbol that was "common" but no longer 2201 needs to be global. */ 2202 output = false; 2203 else 2204 abort (); 2205 2206 /* If this symbol is in a section which is not being included 2207 in the output file, then we don't want to output the 2208 symbol. */ 2209 if (!bfd_is_abs_section (sym->section) 2210 && bfd_section_removed_from_list (output_bfd, 2211 sym->section->output_section)) 2212 output = false; 2213 2214 if (output) 2215 { 2216 if (! generic_add_output_symbol (output_bfd, psymalloc, sym)) 2217 return false; 2218 if (h != NULL) 2219 h->written = true; 2220 } 2221 } 2222 2223 return true; 2224 } 2225 2226 /* Set the section and value of a generic BFD symbol based on a linker 2227 hash table entry. */ 2228 2229 static void 2230 set_symbol_from_hash (asymbol *sym, struct bfd_link_hash_entry *h) 2231 { 2232 switch (h->type) 2233 { 2234 default: 2235 abort (); 2236 break; 2237 case bfd_link_hash_new: 2238 /* This can happen when a constructor symbol is seen but we are 2239 not building constructors. */ 2240 if (sym->section != NULL) 2241 { 2242 BFD_ASSERT ((sym->flags & BSF_CONSTRUCTOR) != 0); 2243 } 2244 else 2245 { 2246 sym->flags |= BSF_CONSTRUCTOR; 2247 sym->section = bfd_abs_section_ptr; 2248 sym->value = 0; 2249 } 2250 break; 2251 case bfd_link_hash_undefined: 2252 sym->section = bfd_und_section_ptr; 2253 sym->value = 0; 2254 break; 2255 case bfd_link_hash_undefweak: 2256 sym->section = bfd_und_section_ptr; 2257 sym->value = 0; 2258 sym->flags |= BSF_WEAK; 2259 break; 2260 case bfd_link_hash_defined: 2261 sym->section = h->u.def.section; 2262 sym->value = h->u.def.value; 2263 break; 2264 case bfd_link_hash_defweak: 2265 sym->flags |= BSF_WEAK; 2266 sym->section = h->u.def.section; 2267 sym->value = h->u.def.value; 2268 break; 2269 case bfd_link_hash_common: 2270 sym->value = h->u.c.size; 2271 if (sym->section == NULL) 2272 sym->section = bfd_com_section_ptr; 2273 else if (! bfd_is_com_section (sym->section)) 2274 { 2275 BFD_ASSERT (bfd_is_und_section (sym->section)); 2276 sym->section = bfd_com_section_ptr; 2277 } 2278 /* Do not set the section; see _bfd_generic_link_output_symbols. */ 2279 break; 2280 case bfd_link_hash_indirect: 2281 case bfd_link_hash_warning: 2282 /* FIXME: What should we do here? */ 2283 break; 2284 } 2285 } 2286 2287 /* Write out a global symbol, if it hasn't already been written out. 2288 This is called for each symbol in the hash table. */ 2289 2290 bool 2291 _bfd_generic_link_write_global_symbol (struct generic_link_hash_entry *h, 2292 void *data) 2293 { 2294 struct generic_write_global_symbol_info *wginfo = 2295 (struct generic_write_global_symbol_info *) data; 2296 asymbol *sym; 2297 2298 if (h->written) 2299 return true; 2300 2301 h->written = true; 2302 2303 if (wginfo->info->strip == strip_all 2304 || (wginfo->info->strip == strip_some 2305 && bfd_hash_lookup (wginfo->info->keep_hash, h->root.root.string, 2306 false, false) == NULL)) 2307 return true; 2308 2309 if (h->sym != NULL) 2310 sym = h->sym; 2311 else 2312 { 2313 sym = bfd_make_empty_symbol (wginfo->output_bfd); 2314 if (!sym) 2315 return false; 2316 sym->name = h->root.root.string; 2317 sym->flags = 0; 2318 } 2319 2320 set_symbol_from_hash (sym, &h->root); 2321 2322 sym->flags |= BSF_GLOBAL; 2323 2324 if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc, 2325 sym)) 2326 { 2327 /* FIXME: No way to return failure. */ 2328 abort (); 2329 } 2330 2331 return true; 2332 } 2333 2334 /* Create a relocation. */ 2335 2336 bool 2337 _bfd_generic_reloc_link_order (bfd *abfd, 2338 struct bfd_link_info *info, 2339 asection *sec, 2340 struct bfd_link_order *link_order) 2341 { 2342 arelent *r; 2343 2344 if (! bfd_link_relocatable (info)) 2345 abort (); 2346 if (sec->orelocation == NULL) 2347 abort (); 2348 2349 r = (arelent *) bfd_alloc (abfd, sizeof (arelent)); 2350 if (r == NULL) 2351 return false; 2352 2353 r->address = link_order->offset; 2354 r->howto = bfd_reloc_type_lookup (abfd, link_order->u.reloc.p->reloc); 2355 if (r->howto == 0) 2356 { 2357 bfd_set_error (bfd_error_bad_value); 2358 return false; 2359 } 2360 2361 /* Get the symbol to use for the relocation. */ 2362 if (link_order->type == bfd_section_reloc_link_order) 2363 r->sym_ptr_ptr = link_order->u.reloc.p->u.section->symbol_ptr_ptr; 2364 else 2365 { 2366 struct generic_link_hash_entry *h; 2367 2368 h = ((struct generic_link_hash_entry *) 2369 bfd_wrapped_link_hash_lookup (abfd, info, 2370 link_order->u.reloc.p->u.name, 2371 false, false, true)); 2372 if (h == NULL 2373 || ! h->written) 2374 { 2375 (*info->callbacks->unattached_reloc) 2376 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0); 2377 bfd_set_error (bfd_error_bad_value); 2378 return false; 2379 } 2380 r->sym_ptr_ptr = &h->sym; 2381 } 2382 2383 /* If this is an inplace reloc, write the addend to the object file. 2384 Otherwise, store it in the reloc addend. */ 2385 if (! r->howto->partial_inplace) 2386 r->addend = link_order->u.reloc.p->addend; 2387 else 2388 { 2389 bfd_size_type size; 2390 bfd_reloc_status_type rstat; 2391 bfd_byte *buf; 2392 bool ok; 2393 file_ptr loc; 2394 2395 size = bfd_get_reloc_size (r->howto); 2396 buf = (bfd_byte *) bfd_zmalloc (size); 2397 if (buf == NULL && size != 0) 2398 return false; 2399 rstat = _bfd_relocate_contents (r->howto, abfd, 2400 (bfd_vma) link_order->u.reloc.p->addend, 2401 buf); 2402 switch (rstat) 2403 { 2404 case bfd_reloc_ok: 2405 break; 2406 default: 2407 case bfd_reloc_outofrange: 2408 abort (); 2409 case bfd_reloc_overflow: 2410 (*info->callbacks->reloc_overflow) 2411 (info, NULL, 2412 (link_order->type == bfd_section_reloc_link_order 2413 ? bfd_section_name (link_order->u.reloc.p->u.section) 2414 : link_order->u.reloc.p->u.name), 2415 r->howto->name, link_order->u.reloc.p->addend, 2416 NULL, NULL, 0); 2417 break; 2418 } 2419 loc = link_order->offset * bfd_octets_per_byte (abfd, sec); 2420 ok = bfd_set_section_contents (abfd, sec, buf, loc, size); 2421 free (buf); 2422 if (! ok) 2423 return false; 2424 2425 r->addend = 0; 2426 } 2427 2428 sec->orelocation[sec->reloc_count] = r; 2429 ++sec->reloc_count; 2430 2431 return true; 2432 } 2433 2434 /* Allocate a new link_order for a section. */ 2435 2436 struct bfd_link_order * 2437 bfd_new_link_order (bfd *abfd, asection *section) 2438 { 2439 size_t amt = sizeof (struct bfd_link_order); 2440 struct bfd_link_order *new_lo; 2441 2442 new_lo = (struct bfd_link_order *) bfd_zalloc (abfd, amt); 2443 if (!new_lo) 2444 return NULL; 2445 2446 new_lo->type = bfd_undefined_link_order; 2447 2448 if (section->map_tail.link_order != NULL) 2449 section->map_tail.link_order->next = new_lo; 2450 else 2451 section->map_head.link_order = new_lo; 2452 section->map_tail.link_order = new_lo; 2453 2454 return new_lo; 2455 } 2456 2457 /* Default link order processing routine. Note that we can not handle 2458 the reloc_link_order types here, since they depend upon the details 2459 of how the particular backends generates relocs. */ 2460 2461 bool 2462 _bfd_default_link_order (bfd *abfd, 2463 struct bfd_link_info *info, 2464 asection *sec, 2465 struct bfd_link_order *link_order) 2466 { 2467 switch (link_order->type) 2468 { 2469 case bfd_undefined_link_order: 2470 case bfd_section_reloc_link_order: 2471 case bfd_symbol_reloc_link_order: 2472 default: 2473 abort (); 2474 case bfd_indirect_link_order: 2475 return default_indirect_link_order (abfd, info, sec, link_order, 2476 false); 2477 case bfd_data_link_order: 2478 return default_data_link_order (abfd, info, sec, link_order); 2479 } 2480 } 2481 2482 /* Default routine to handle a bfd_data_link_order. */ 2483 2484 static bool 2485 default_data_link_order (bfd *abfd, 2486 struct bfd_link_info *info, 2487 asection *sec, 2488 struct bfd_link_order *link_order) 2489 { 2490 bfd_size_type size; 2491 size_t fill_size; 2492 bfd_byte *fill; 2493 file_ptr loc; 2494 bool result; 2495 2496 BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0); 2497 2498 size = link_order->size; 2499 if (size == 0) 2500 return true; 2501 2502 fill = link_order->u.data.contents; 2503 fill_size = link_order->u.data.size; 2504 if (fill_size == 0) 2505 { 2506 fill = abfd->arch_info->fill (size, info->big_endian, 2507 (sec->flags & SEC_CODE) != 0); 2508 if (fill == NULL) 2509 return false; 2510 } 2511 else if (fill_size < size) 2512 { 2513 bfd_byte *p; 2514 fill = (bfd_byte *) bfd_malloc (size); 2515 if (fill == NULL) 2516 return false; 2517 p = fill; 2518 if (fill_size == 1) 2519 memset (p, (int) link_order->u.data.contents[0], (size_t) size); 2520 else 2521 { 2522 do 2523 { 2524 memcpy (p, link_order->u.data.contents, fill_size); 2525 p += fill_size; 2526 size -= fill_size; 2527 } 2528 while (size >= fill_size); 2529 if (size != 0) 2530 memcpy (p, link_order->u.data.contents, (size_t) size); 2531 size = link_order->size; 2532 } 2533 } 2534 2535 loc = link_order->offset * bfd_octets_per_byte (abfd, sec); 2536 result = bfd_set_section_contents (abfd, sec, fill, loc, size); 2537 2538 if (fill != link_order->u.data.contents) 2539 free (fill); 2540 return result; 2541 } 2542 2543 /* Default routine to handle a bfd_indirect_link_order. */ 2544 2545 static bool 2546 default_indirect_link_order (bfd *output_bfd, 2547 struct bfd_link_info *info, 2548 asection *output_section, 2549 struct bfd_link_order *link_order, 2550 bool generic_linker) 2551 { 2552 asection *input_section; 2553 bfd *input_bfd; 2554 bfd_byte *alloced = NULL; 2555 bfd_byte *new_contents; 2556 file_ptr loc; 2557 2558 BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0); 2559 2560 input_section = link_order->u.indirect.section; 2561 input_bfd = input_section->owner; 2562 if (input_section->size == 0) 2563 return true; 2564 2565 BFD_ASSERT (input_section->output_section == output_section); 2566 BFD_ASSERT (input_section->output_offset == link_order->offset); 2567 BFD_ASSERT (input_section->size == link_order->size); 2568 2569 if (bfd_link_relocatable (info) 2570 && input_section->reloc_count > 0 2571 && output_section->orelocation == NULL) 2572 { 2573 /* Space has not been allocated for the output relocations. 2574 This can happen when we are called by a specific backend 2575 because somebody is attempting to link together different 2576 types of object files. Handling this case correctly is 2577 difficult, and sometimes impossible. */ 2578 _bfd_error_handler 2579 /* xgettext:c-format */ 2580 (_("attempt to do relocatable link with %s input and %s output"), 2581 bfd_get_target (input_bfd), bfd_get_target (output_bfd)); 2582 bfd_set_error (bfd_error_wrong_format); 2583 return false; 2584 } 2585 2586 if (! generic_linker) 2587 { 2588 asymbol **sympp; 2589 asymbol **symppend; 2590 2591 /* Get the canonical symbols. The generic linker will always 2592 have retrieved them by this point, but we are being called by 2593 a specific linker, presumably because we are linking 2594 different types of object files together. */ 2595 if (!bfd_generic_link_read_symbols (input_bfd)) 2596 return false; 2597 2598 /* Since we have been called by a specific linker, rather than 2599 the generic linker, the values of the symbols will not be 2600 right. They will be the values as seen in the input file, 2601 not the values of the final link. We need to fix them up 2602 before we can relocate the section. */ 2603 sympp = _bfd_generic_link_get_symbols (input_bfd); 2604 symppend = sympp + _bfd_generic_link_get_symcount (input_bfd); 2605 for (; sympp < symppend; sympp++) 2606 { 2607 asymbol *sym; 2608 struct bfd_link_hash_entry *h; 2609 2610 sym = *sympp; 2611 2612 if ((sym->flags & (BSF_INDIRECT 2613 | BSF_WARNING 2614 | BSF_GLOBAL 2615 | BSF_CONSTRUCTOR 2616 | BSF_WEAK)) != 0 2617 || bfd_is_und_section (bfd_asymbol_section (sym)) 2618 || bfd_is_com_section (bfd_asymbol_section (sym)) 2619 || bfd_is_ind_section (bfd_asymbol_section (sym))) 2620 { 2621 /* sym->udata may have been set by 2622 generic_link_add_symbol_list. */ 2623 if (sym->udata.p != NULL) 2624 h = (struct bfd_link_hash_entry *) sym->udata.p; 2625 else if (bfd_is_und_section (bfd_asymbol_section (sym))) 2626 h = bfd_wrapped_link_hash_lookup (output_bfd, info, 2627 bfd_asymbol_name (sym), 2628 false, false, true); 2629 else 2630 h = bfd_link_hash_lookup (info->hash, 2631 bfd_asymbol_name (sym), 2632 false, false, true); 2633 if (h != NULL) 2634 set_symbol_from_hash (sym, h); 2635 } 2636 } 2637 } 2638 2639 if ((output_section->flags & (SEC_GROUP | SEC_LINKER_CREATED)) == SEC_GROUP 2640 && input_section->size != 0) 2641 { 2642 /* Group section contents are set by bfd_elf_set_group_contents. */ 2643 if (!output_bfd->output_has_begun) 2644 { 2645 /* FIXME: This hack ensures bfd_elf_set_group_contents is called. */ 2646 if (!bfd_set_section_contents (output_bfd, output_section, "", 0, 1)) 2647 goto error_return; 2648 } 2649 new_contents = output_section->contents; 2650 BFD_ASSERT (new_contents != NULL); 2651 BFD_ASSERT (input_section->output_offset == 0); 2652 } 2653 else 2654 { 2655 /* Get and relocate the section contents. */ 2656 new_contents = (bfd_get_relocated_section_contents 2657 (output_bfd, info, link_order, NULL, 2658 bfd_link_relocatable (info), 2659 _bfd_generic_link_get_symbols (input_bfd))); 2660 alloced = new_contents; 2661 if (!new_contents) 2662 goto error_return; 2663 } 2664 2665 /* Output the section contents. */ 2666 loc = (input_section->output_offset 2667 * bfd_octets_per_byte (output_bfd, output_section)); 2668 if (! bfd_set_section_contents (output_bfd, output_section, 2669 new_contents, loc, input_section->size)) 2670 goto error_return; 2671 2672 free (alloced); 2673 return true; 2674 2675 error_return: 2676 free (alloced); 2677 return false; 2678 } 2679 2680 /* A little routine to count the number of relocs in a link_order 2681 list. */ 2682 2683 unsigned int 2684 _bfd_count_link_order_relocs (struct bfd_link_order *link_order) 2685 { 2686 register unsigned int c; 2687 register struct bfd_link_order *l; 2688 2689 c = 0; 2690 for (l = link_order; l != NULL; l = l->next) 2691 { 2692 if (l->type == bfd_section_reloc_link_order 2693 || l->type == bfd_symbol_reloc_link_order) 2694 ++c; 2695 } 2696 2697 return c; 2698 } 2699 2700 /* 2701 FUNCTION 2702 bfd_link_split_section 2703 2704 SYNOPSIS 2705 bool bfd_link_split_section (bfd *abfd, asection *sec); 2706 2707 DESCRIPTION 2708 Return nonzero if @var{sec} should be split during a 2709 reloceatable or final link. 2710 2711 .#define bfd_link_split_section(abfd, sec) \ 2712 . BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec)) 2713 . 2714 2715 */ 2716 2717 bool 2718 _bfd_generic_link_split_section (bfd *abfd ATTRIBUTE_UNUSED, 2719 asection *sec ATTRIBUTE_UNUSED) 2720 { 2721 return false; 2722 } 2723 2724 /* 2725 FUNCTION 2726 bfd_section_already_linked 2727 2728 SYNOPSIS 2729 bool bfd_section_already_linked (bfd *abfd, 2730 asection *sec, 2731 struct bfd_link_info *info); 2732 2733 DESCRIPTION 2734 Check if @var{data} has been already linked during a reloceatable 2735 or final link. Return TRUE if it has. 2736 2737 .#define bfd_section_already_linked(abfd, sec, info) \ 2738 . BFD_SEND (abfd, _section_already_linked, (abfd, sec, info)) 2739 . 2740 2741 */ 2742 2743 /* Sections marked with the SEC_LINK_ONCE flag should only be linked 2744 once into the output. This routine checks each section, and 2745 arrange to discard it if a section of the same name has already 2746 been linked. This code assumes that all relevant sections have the 2747 SEC_LINK_ONCE flag set; that is, it does not depend solely upon the 2748 section name. bfd_section_already_linked is called via 2749 bfd_map_over_sections. */ 2750 2751 /* The hash table. */ 2752 2753 static struct bfd_hash_table _bfd_section_already_linked_table; 2754 2755 /* Support routines for the hash table used by section_already_linked, 2756 initialize the table, traverse, lookup, fill in an entry and remove 2757 the table. */ 2758 2759 void 2760 bfd_section_already_linked_table_traverse 2761 (bool (*func) (struct bfd_section_already_linked_hash_entry *, void *), 2762 void *info) 2763 { 2764 bfd_hash_traverse (&_bfd_section_already_linked_table, 2765 (bool (*) (struct bfd_hash_entry *, void *)) func, 2766 info); 2767 } 2768 2769 struct bfd_section_already_linked_hash_entry * 2770 bfd_section_already_linked_table_lookup (const char *name) 2771 { 2772 return ((struct bfd_section_already_linked_hash_entry *) 2773 bfd_hash_lookup (&_bfd_section_already_linked_table, name, 2774 true, false)); 2775 } 2776 2777 bool 2778 bfd_section_already_linked_table_insert 2779 (struct bfd_section_already_linked_hash_entry *already_linked_list, 2780 asection *sec) 2781 { 2782 struct bfd_section_already_linked *l; 2783 2784 /* Allocate the memory from the same obstack as the hash table is 2785 kept in. */ 2786 l = (struct bfd_section_already_linked *) 2787 bfd_hash_allocate (&_bfd_section_already_linked_table, sizeof *l); 2788 if (l == NULL) 2789 return false; 2790 l->sec = sec; 2791 l->next = already_linked_list->entry; 2792 already_linked_list->entry = l; 2793 return true; 2794 } 2795 2796 static struct bfd_hash_entry * 2797 already_linked_newfunc (struct bfd_hash_entry *entry ATTRIBUTE_UNUSED, 2798 struct bfd_hash_table *table, 2799 const char *string ATTRIBUTE_UNUSED) 2800 { 2801 struct bfd_section_already_linked_hash_entry *ret = 2802 (struct bfd_section_already_linked_hash_entry *) 2803 bfd_hash_allocate (table, sizeof *ret); 2804 2805 if (ret == NULL) 2806 return NULL; 2807 2808 ret->entry = NULL; 2809 2810 return &ret->root; 2811 } 2812 2813 bool 2814 bfd_section_already_linked_table_init (void) 2815 { 2816 return bfd_hash_table_init_n (&_bfd_section_already_linked_table, 2817 already_linked_newfunc, 2818 sizeof (struct bfd_section_already_linked_hash_entry), 2819 42); 2820 } 2821 2822 void 2823 bfd_section_already_linked_table_free (void) 2824 { 2825 bfd_hash_table_free (&_bfd_section_already_linked_table); 2826 } 2827 2828 /* Report warnings as appropriate for duplicate section SEC. 2829 Return FALSE if we decide to keep SEC after all. */ 2830 2831 bool 2832 _bfd_handle_already_linked (asection *sec, 2833 struct bfd_section_already_linked *l, 2834 struct bfd_link_info *info) 2835 { 2836 switch (sec->flags & SEC_LINK_DUPLICATES) 2837 { 2838 default: 2839 abort (); 2840 2841 case SEC_LINK_DUPLICATES_DISCARD: 2842 /* If we found an LTO IR match for this comdat group on 2843 the first pass, replace it with the LTO output on the 2844 second pass. We can't simply choose real object 2845 files over IR because the first pass may contain a 2846 mix of LTO and normal objects and we must keep the 2847 first match, be it IR or real. */ 2848 if (sec->owner->lto_output 2849 && (l->sec->owner->flags & BFD_PLUGIN) != 0) 2850 { 2851 l->sec = sec; 2852 return false; 2853 } 2854 break; 2855 2856 case SEC_LINK_DUPLICATES_ONE_ONLY: 2857 info->callbacks->einfo 2858 /* xgettext:c-format */ 2859 (_("%pB: ignoring duplicate section `%pA'\n"), 2860 sec->owner, sec); 2861 break; 2862 2863 case SEC_LINK_DUPLICATES_SAME_SIZE: 2864 if ((l->sec->owner->flags & BFD_PLUGIN) != 0) 2865 ; 2866 else if (sec->size != l->sec->size) 2867 info->callbacks->einfo 2868 /* xgettext:c-format */ 2869 (_("%pB: duplicate section `%pA' has different size\n"), 2870 sec->owner, sec); 2871 break; 2872 2873 case SEC_LINK_DUPLICATES_SAME_CONTENTS: 2874 if ((l->sec->owner->flags & BFD_PLUGIN) != 0) 2875 ; 2876 else if (sec->size != l->sec->size) 2877 info->callbacks->einfo 2878 /* xgettext:c-format */ 2879 (_("%pB: duplicate section `%pA' has different size\n"), 2880 sec->owner, sec); 2881 else if (sec->size != 0) 2882 { 2883 bfd_byte *sec_contents, *l_sec_contents = NULL; 2884 2885 if (!bfd_malloc_and_get_section (sec->owner, sec, &sec_contents)) 2886 info->callbacks->einfo 2887 /* xgettext:c-format */ 2888 (_("%pB: could not read contents of section `%pA'\n"), 2889 sec->owner, sec); 2890 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec, 2891 &l_sec_contents)) 2892 info->callbacks->einfo 2893 /* xgettext:c-format */ 2894 (_("%pB: could not read contents of section `%pA'\n"), 2895 l->sec->owner, l->sec); 2896 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0) 2897 info->callbacks->einfo 2898 /* xgettext:c-format */ 2899 (_("%pB: duplicate section `%pA' has different contents\n"), 2900 sec->owner, sec); 2901 2902 free (sec_contents); 2903 free (l_sec_contents); 2904 } 2905 break; 2906 } 2907 2908 /* Set the output_section field so that lang_add_section 2909 does not create a lang_input_section structure for this 2910 section. Since there might be a symbol in the section 2911 being discarded, we must retain a pointer to the section 2912 which we are really going to use. */ 2913 sec->output_section = bfd_abs_section_ptr; 2914 sec->kept_section = l->sec; 2915 return true; 2916 } 2917 2918 /* This is used on non-ELF inputs. */ 2919 2920 bool 2921 _bfd_generic_section_already_linked (bfd *abfd ATTRIBUTE_UNUSED, 2922 asection *sec, 2923 struct bfd_link_info *info) 2924 { 2925 const char *name; 2926 struct bfd_section_already_linked *l; 2927 struct bfd_section_already_linked_hash_entry *already_linked_list; 2928 2929 if ((sec->flags & SEC_LINK_ONCE) == 0) 2930 return false; 2931 2932 /* The generic linker doesn't handle section groups. */ 2933 if ((sec->flags & SEC_GROUP) != 0) 2934 return false; 2935 2936 /* FIXME: When doing a relocatable link, we may have trouble 2937 copying relocations in other sections that refer to local symbols 2938 in the section being discarded. Those relocations will have to 2939 be converted somehow; as of this writing I'm not sure that any of 2940 the backends handle that correctly. 2941 2942 It is tempting to instead not discard link once sections when 2943 doing a relocatable link (technically, they should be discarded 2944 whenever we are building constructors). However, that fails, 2945 because the linker winds up combining all the link once sections 2946 into a single large link once section, which defeats the purpose 2947 of having link once sections in the first place. */ 2948 2949 name = bfd_section_name (sec); 2950 2951 already_linked_list = bfd_section_already_linked_table_lookup (name); 2952 2953 l = already_linked_list->entry; 2954 if (l != NULL) 2955 { 2956 /* The section has already been linked. See if we should 2957 issue a warning. */ 2958 return _bfd_handle_already_linked (sec, l, info); 2959 } 2960 2961 /* This is the first section with this name. Record it. */ 2962 if (!bfd_section_already_linked_table_insert (already_linked_list, sec)) 2963 info->callbacks->einfo (_("%F%P: already_linked_table: %E\n")); 2964 return false; 2965 } 2966 2967 /* Choose a neighbouring section to S in OBFD that will be output, or 2968 the absolute section if ADDR is out of bounds of the neighbours. */ 2969 2970 asection * 2971 _bfd_nearby_section (bfd *obfd, asection *s, bfd_vma addr) 2972 { 2973 asection *next, *prev, *best; 2974 2975 /* Find preceding kept section. */ 2976 for (prev = s->prev; prev != NULL; prev = prev->prev) 2977 if ((prev->flags & SEC_EXCLUDE) == 0 2978 && !bfd_section_removed_from_list (obfd, prev)) 2979 break; 2980 2981 /* Find following kept section. Start at prev->next because 2982 other sections may have been added after S was removed. */ 2983 if (s->prev != NULL) 2984 next = s->prev->next; 2985 else 2986 next = s->owner->sections; 2987 for (; next != NULL; next = next->next) 2988 if ((next->flags & SEC_EXCLUDE) == 0 2989 && !bfd_section_removed_from_list (obfd, next)) 2990 break; 2991 2992 /* Choose better of two sections, based on flags. The idea 2993 is to choose a section that will be in the same segment 2994 as S would have been if it was kept. */ 2995 best = next; 2996 if (prev == NULL) 2997 { 2998 if (next == NULL) 2999 best = bfd_abs_section_ptr; 3000 } 3001 else if (next == NULL) 3002 best = prev; 3003 else if (((prev->flags ^ next->flags) 3004 & (SEC_ALLOC | SEC_THREAD_LOCAL | SEC_LOAD)) != 0) 3005 { 3006 if (((next->flags ^ s->flags) 3007 & (SEC_ALLOC | SEC_THREAD_LOCAL)) != 0 3008 /* We prefer to choose a loaded section. Section S 3009 doesn't have SEC_LOAD set (it being excluded, that 3010 part of the flag processing didn't happen) so we 3011 can't compare that flag to those of NEXT and PREV. */ 3012 || ((prev->flags & SEC_LOAD) != 0 3013 && (next->flags & SEC_LOAD) == 0)) 3014 best = prev; 3015 } 3016 else if (((prev->flags ^ next->flags) & SEC_READONLY) != 0) 3017 { 3018 if (((next->flags ^ s->flags) & SEC_READONLY) != 0) 3019 best = prev; 3020 } 3021 else if (((prev->flags ^ next->flags) & SEC_CODE) != 0) 3022 { 3023 if (((next->flags ^ s->flags) & SEC_CODE) != 0) 3024 best = prev; 3025 } 3026 else 3027 { 3028 /* Flags we care about are the same. Prefer the following 3029 section if that will result in a positive valued sym. */ 3030 if (addr < next->vma) 3031 best = prev; 3032 } 3033 3034 return best; 3035 } 3036 3037 /* Convert symbols in excluded output sections to use a kept section. */ 3038 3039 static bool 3040 fix_syms (struct bfd_link_hash_entry *h, void *data) 3041 { 3042 bfd *obfd = (bfd *) data; 3043 3044 if (h->type == bfd_link_hash_defined 3045 || h->type == bfd_link_hash_defweak) 3046 { 3047 asection *s = h->u.def.section; 3048 if (s != NULL 3049 && s->output_section != NULL 3050 && (s->output_section->flags & SEC_EXCLUDE) != 0 3051 && bfd_section_removed_from_list (obfd, s->output_section)) 3052 { 3053 asection *op; 3054 3055 h->u.def.value += s->output_offset + s->output_section->vma; 3056 op = _bfd_nearby_section (obfd, s->output_section, h->u.def.value); 3057 h->u.def.value -= op->vma; 3058 h->u.def.section = op; 3059 } 3060 } 3061 3062 return true; 3063 } 3064 3065 void 3066 _bfd_fix_excluded_sec_syms (bfd *obfd, struct bfd_link_info *info) 3067 { 3068 bfd_link_hash_traverse (info->hash, fix_syms, obfd); 3069 } 3070 3071 /* 3072 FUNCTION 3073 bfd_generic_define_common_symbol 3074 3075 SYNOPSIS 3076 bool bfd_generic_define_common_symbol 3077 (bfd *output_bfd, struct bfd_link_info *info, 3078 struct bfd_link_hash_entry *h); 3079 3080 DESCRIPTION 3081 Convert common symbol @var{h} into a defined symbol. 3082 Return TRUE on success and FALSE on failure. 3083 3084 .#define bfd_define_common_symbol(output_bfd, info, h) \ 3085 . BFD_SEND (output_bfd, _bfd_define_common_symbol, (output_bfd, info, h)) 3086 . 3087 */ 3088 3089 bool 3090 bfd_generic_define_common_symbol (bfd *output_bfd, 3091 struct bfd_link_info *info ATTRIBUTE_UNUSED, 3092 struct bfd_link_hash_entry *h) 3093 { 3094 unsigned int power_of_two; 3095 bfd_vma alignment, size; 3096 asection *section; 3097 3098 BFD_ASSERT (h != NULL && h->type == bfd_link_hash_common); 3099 3100 size = h->u.c.size; 3101 power_of_two = h->u.c.p->alignment_power; 3102 section = h->u.c.p->section; 3103 3104 /* Increase the size of the section to align the common symbol. 3105 The alignment must be a power of two. But if the section does 3106 not have any alignment requirement then do not increase the 3107 alignment unnecessarily. */ 3108 if (power_of_two) 3109 alignment = bfd_octets_per_byte (output_bfd, section) << power_of_two; 3110 else 3111 alignment = 1; 3112 BFD_ASSERT (alignment != 0 && (alignment & -alignment) == alignment); 3113 section->size += alignment - 1; 3114 section->size &= -alignment; 3115 3116 /* Adjust the section's overall alignment if necessary. */ 3117 if (power_of_two > section->alignment_power) 3118 section->alignment_power = power_of_two; 3119 3120 /* Change the symbol from common to defined. */ 3121 h->type = bfd_link_hash_defined; 3122 h->u.def.section = section; 3123 h->u.def.value = section->size; 3124 3125 /* Increase the size of the section. */ 3126 section->size += size; 3127 3128 /* Make sure the section is allocated in memory, and make sure that 3129 it is no longer a common section. */ 3130 section->flags |= SEC_ALLOC; 3131 section->flags &= ~(SEC_IS_COMMON | SEC_HAS_CONTENTS); 3132 return true; 3133 } 3134 3135 /* 3136 FUNCTION 3137 _bfd_generic_link_hide_symbol 3138 3139 SYNOPSIS 3140 void _bfd_generic_link_hide_symbol 3141 (bfd *output_bfd, struct bfd_link_info *info, 3142 struct bfd_link_hash_entry *h); 3143 3144 DESCRIPTION 3145 Hide symbol @var{h}. 3146 This is an internal function. It should not be called from 3147 outside the BFD library. 3148 3149 .#define bfd_link_hide_symbol(output_bfd, info, h) \ 3150 . BFD_SEND (output_bfd, _bfd_link_hide_symbol, (output_bfd, info, h)) 3151 . 3152 */ 3153 3154 void 3155 _bfd_generic_link_hide_symbol (bfd *output_bfd ATTRIBUTE_UNUSED, 3156 struct bfd_link_info *info ATTRIBUTE_UNUSED, 3157 struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED) 3158 { 3159 } 3160 3161 /* 3162 FUNCTION 3163 bfd_generic_define_start_stop 3164 3165 SYNOPSIS 3166 struct bfd_link_hash_entry *bfd_generic_define_start_stop 3167 (struct bfd_link_info *info, 3168 const char *symbol, asection *sec); 3169 3170 DESCRIPTION 3171 Define a __start, __stop, .startof. or .sizeof. symbol. 3172 Return the symbol or NULL if no such undefined symbol exists. 3173 3174 .#define bfd_define_start_stop(output_bfd, info, symbol, sec) \ 3175 . BFD_SEND (output_bfd, _bfd_define_start_stop, (info, symbol, sec)) 3176 . 3177 */ 3178 3179 struct bfd_link_hash_entry * 3180 bfd_generic_define_start_stop (struct bfd_link_info *info, 3181 const char *symbol, asection *sec) 3182 { 3183 struct bfd_link_hash_entry *h; 3184 3185 h = bfd_link_hash_lookup (info->hash, symbol, false, false, true); 3186 if (h != NULL 3187 && !h->ldscript_def 3188 && (h->type == bfd_link_hash_undefined 3189 || h->type == bfd_link_hash_undefweak)) 3190 { 3191 h->type = bfd_link_hash_defined; 3192 h->u.def.section = sec; 3193 h->u.def.value = 0; 3194 return h; 3195 } 3196 return NULL; 3197 } 3198 3199 /* 3200 FUNCTION 3201 bfd_find_version_for_sym 3202 3203 SYNOPSIS 3204 struct bfd_elf_version_tree * bfd_find_version_for_sym 3205 (struct bfd_elf_version_tree *verdefs, 3206 const char *sym_name, bool *hide); 3207 3208 DESCRIPTION 3209 Search an elf version script tree for symbol versioning 3210 info and export / don't-export status for a given symbol. 3211 Return non-NULL on success and NULL on failure; also sets 3212 the output @samp{hide} boolean parameter. 3213 3214 */ 3215 3216 struct bfd_elf_version_tree * 3217 bfd_find_version_for_sym (struct bfd_elf_version_tree *verdefs, 3218 const char *sym_name, 3219 bool *hide) 3220 { 3221 struct bfd_elf_version_tree *t; 3222 struct bfd_elf_version_tree *local_ver, *global_ver, *exist_ver; 3223 struct bfd_elf_version_tree *star_local_ver, *star_global_ver; 3224 3225 local_ver = NULL; 3226 global_ver = NULL; 3227 star_local_ver = NULL; 3228 star_global_ver = NULL; 3229 exist_ver = NULL; 3230 for (t = verdefs; t != NULL; t = t->next) 3231 { 3232 if (t->globals.list != NULL) 3233 { 3234 struct bfd_elf_version_expr *d = NULL; 3235 3236 while ((d = (*t->match) (&t->globals, d, sym_name)) != NULL) 3237 { 3238 if (d->literal || strcmp (d->pattern, "*") != 0) 3239 global_ver = t; 3240 else 3241 star_global_ver = t; 3242 if (d->symver) 3243 exist_ver = t; 3244 d->script = 1; 3245 /* If the match is a wildcard pattern, keep looking for 3246 a more explicit, perhaps even local, match. */ 3247 if (d->literal) 3248 break; 3249 } 3250 3251 if (d != NULL) 3252 break; 3253 } 3254 3255 if (t->locals.list != NULL) 3256 { 3257 struct bfd_elf_version_expr *d = NULL; 3258 3259 while ((d = (*t->match) (&t->locals, d, sym_name)) != NULL) 3260 { 3261 if (d->literal || strcmp (d->pattern, "*") != 0) 3262 local_ver = t; 3263 else 3264 star_local_ver = t; 3265 /* If the match is a wildcard pattern, keep looking for 3266 a more explicit, perhaps even global, match. */ 3267 if (d->literal) 3268 { 3269 /* An exact match overrides a global wildcard. */ 3270 global_ver = NULL; 3271 star_global_ver = NULL; 3272 break; 3273 } 3274 } 3275 3276 if (d != NULL) 3277 break; 3278 } 3279 } 3280 3281 if (global_ver == NULL && local_ver == NULL) 3282 global_ver = star_global_ver; 3283 3284 if (global_ver != NULL) 3285 { 3286 /* If we already have a versioned symbol that matches the 3287 node for this symbol, then we don't want to create a 3288 duplicate from the unversioned symbol. Instead hide the 3289 unversioned symbol. */ 3290 *hide = exist_ver == global_ver; 3291 return global_ver; 3292 } 3293 3294 if (local_ver == NULL) 3295 local_ver = star_local_ver; 3296 3297 if (local_ver != NULL) 3298 { 3299 *hide = true; 3300 return local_ver; 3301 } 3302 3303 return NULL; 3304 } 3305 3306 /* 3307 FUNCTION 3308 bfd_hide_sym_by_version 3309 3310 SYNOPSIS 3311 bool bfd_hide_sym_by_version 3312 (struct bfd_elf_version_tree *verdefs, const char *sym_name); 3313 3314 DESCRIPTION 3315 Search an elf version script tree for symbol versioning 3316 info for a given symbol. Return TRUE if the symbol is hidden. 3317 3318 */ 3319 3320 bool 3321 bfd_hide_sym_by_version (struct bfd_elf_version_tree *verdefs, 3322 const char *sym_name) 3323 { 3324 bool hidden = false; 3325 bfd_find_version_for_sym (verdefs, sym_name, &hidden); 3326 return hidden; 3327 } 3328 3329 /* 3330 FUNCTION 3331 bfd_link_check_relocs 3332 3333 SYNOPSIS 3334 bool bfd_link_check_relocs 3335 (bfd *abfd, struct bfd_link_info *info); 3336 3337 DESCRIPTION 3338 Checks the relocs in ABFD for validity. 3339 Does not execute the relocs. 3340 Return TRUE if everything is OK, FALSE otherwise. 3341 This is the external entry point to this code. 3342 */ 3343 3344 bool 3345 bfd_link_check_relocs (bfd *abfd, struct bfd_link_info *info) 3346 { 3347 return BFD_SEND (abfd, _bfd_link_check_relocs, (abfd, info)); 3348 } 3349 3350 /* 3351 FUNCTION 3352 _bfd_generic_link_check_relocs 3353 3354 SYNOPSIS 3355 bool _bfd_generic_link_check_relocs 3356 (bfd *abfd, struct bfd_link_info *info); 3357 3358 DESCRIPTION 3359 Stub function for targets that do not implement reloc checking. 3360 Return TRUE. 3361 This is an internal function. It should not be called from 3362 outside the BFD library. 3363 */ 3364 3365 bool 3366 _bfd_generic_link_check_relocs (bfd *abfd ATTRIBUTE_UNUSED, 3367 struct bfd_link_info *info ATTRIBUTE_UNUSED) 3368 { 3369 return true; 3370 } 3371 3372 /* 3373 FUNCTION 3374 bfd_merge_private_bfd_data 3375 3376 SYNOPSIS 3377 bool bfd_merge_private_bfd_data 3378 (bfd *ibfd, struct bfd_link_info *info); 3379 3380 DESCRIPTION 3381 Merge private BFD information from the BFD @var{ibfd} to the 3382 the output file BFD when linking. Return <<TRUE>> on success, 3383 <<FALSE>> on error. Possible error returns are: 3384 3385 o <<bfd_error_no_memory>> - 3386 Not enough memory exists to create private data for @var{obfd}. 3387 3388 .#define bfd_merge_private_bfd_data(ibfd, info) \ 3389 . BFD_SEND ((info)->output_bfd, _bfd_merge_private_bfd_data, \ 3390 . (ibfd, info)) 3391 */ 3392 3393 /* 3394 INTERNAL_FUNCTION 3395 _bfd_generic_verify_endian_match 3396 3397 SYNOPSIS 3398 bool _bfd_generic_verify_endian_match 3399 (bfd *ibfd, struct bfd_link_info *info); 3400 3401 DESCRIPTION 3402 Can be used from / for bfd_merge_private_bfd_data to check that 3403 endianness matches between input and output file. Returns 3404 TRUE for a match, otherwise returns FALSE and emits an error. 3405 */ 3406 3407 bool 3408 _bfd_generic_verify_endian_match (bfd *ibfd, struct bfd_link_info *info) 3409 { 3410 bfd *obfd = info->output_bfd; 3411 3412 if (ibfd->xvec->byteorder != obfd->xvec->byteorder 3413 && ibfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN 3414 && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN) 3415 { 3416 if (bfd_big_endian (ibfd)) 3417 _bfd_error_handler (_("%pB: compiled for a big endian system " 3418 "and target is little endian"), ibfd); 3419 else 3420 _bfd_error_handler (_("%pB: compiled for a little endian system " 3421 "and target is big endian"), ibfd); 3422 bfd_set_error (bfd_error_wrong_format); 3423 return false; 3424 } 3425 3426 return true; 3427 } 3428 3429 int 3430 _bfd_nolink_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED, 3431 struct bfd_link_info *info ATTRIBUTE_UNUSED) 3432 { 3433 return 0; 3434 } 3435 3436 bool 3437 _bfd_nolink_bfd_relax_section (bfd *abfd, 3438 asection *section ATTRIBUTE_UNUSED, 3439 struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 3440 bool *again ATTRIBUTE_UNUSED) 3441 { 3442 return _bfd_bool_bfd_false_error (abfd); 3443 } 3444 3445 bfd_byte * 3446 _bfd_nolink_bfd_get_relocated_section_contents 3447 (bfd *abfd, 3448 struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 3449 struct bfd_link_order *link_order ATTRIBUTE_UNUSED, 3450 bfd_byte *data ATTRIBUTE_UNUSED, 3451 bool relocatable ATTRIBUTE_UNUSED, 3452 asymbol **symbols ATTRIBUTE_UNUSED) 3453 { 3454 return (bfd_byte *) _bfd_ptr_bfd_null_error (abfd); 3455 } 3456 3457 bool 3458 _bfd_nolink_bfd_lookup_section_flags 3459 (struct bfd_link_info *info ATTRIBUTE_UNUSED, 3460 struct flag_info *flaginfo ATTRIBUTE_UNUSED, 3461 asection *section) 3462 { 3463 return _bfd_bool_bfd_false_error (section->owner); 3464 } 3465 3466 bool 3467 _bfd_nolink_bfd_is_group_section (bfd *abfd, 3468 const asection *sec ATTRIBUTE_UNUSED) 3469 { 3470 return _bfd_bool_bfd_false_error (abfd); 3471 } 3472 3473 const char * 3474 _bfd_nolink_bfd_group_name (bfd *abfd, 3475 const asection *sec ATTRIBUTE_UNUSED) 3476 { 3477 return _bfd_ptr_bfd_null_error (abfd); 3478 } 3479 3480 bool 3481 _bfd_nolink_bfd_discard_group (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) 3482 { 3483 return _bfd_bool_bfd_false_error (abfd); 3484 } 3485 3486 struct bfd_link_hash_table * 3487 _bfd_nolink_bfd_link_hash_table_create (bfd *abfd) 3488 { 3489 return (struct bfd_link_hash_table *) _bfd_ptr_bfd_null_error (abfd); 3490 } 3491 3492 void 3493 _bfd_nolink_bfd_link_just_syms (asection *sec ATTRIBUTE_UNUSED, 3494 struct bfd_link_info *info ATTRIBUTE_UNUSED) 3495 { 3496 } 3497 3498 void 3499 _bfd_nolink_bfd_copy_link_hash_symbol_type 3500 (bfd *abfd ATTRIBUTE_UNUSED, 3501 struct bfd_link_hash_entry *from ATTRIBUTE_UNUSED, 3502 struct bfd_link_hash_entry *to ATTRIBUTE_UNUSED) 3503 { 3504 } 3505 3506 bool 3507 _bfd_nolink_bfd_link_split_section (bfd *abfd, asection *sec ATTRIBUTE_UNUSED) 3508 { 3509 return _bfd_bool_bfd_false_error (abfd); 3510 } 3511 3512 bool 3513 _bfd_nolink_section_already_linked (bfd *abfd, 3514 asection *sec ATTRIBUTE_UNUSED, 3515 struct bfd_link_info *info ATTRIBUTE_UNUSED) 3516 { 3517 return _bfd_bool_bfd_false_error (abfd); 3518 } 3519 3520 bool 3521 _bfd_nolink_bfd_define_common_symbol 3522 (bfd *abfd, 3523 struct bfd_link_info *info ATTRIBUTE_UNUSED, 3524 struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED) 3525 { 3526 return _bfd_bool_bfd_false_error (abfd); 3527 } 3528 3529 struct bfd_link_hash_entry * 3530 _bfd_nolink_bfd_define_start_stop (struct bfd_link_info *info ATTRIBUTE_UNUSED, 3531 const char *name ATTRIBUTE_UNUSED, 3532 asection *sec) 3533 { 3534 return (struct bfd_link_hash_entry *) _bfd_ptr_bfd_null_error (sec->owner); 3535 } 3536 3537 /* Return false if linker should avoid caching relocation infomation 3538 and symbol tables of input files in memory. */ 3539 3540 bool 3541 _bfd_link_keep_memory (struct bfd_link_info * info) 3542 { 3543 bfd *abfd; 3544 bfd_size_type size; 3545 3546 if (!info->keep_memory) 3547 return false; 3548 3549 if (info->max_cache_size == (bfd_size_type) -1) 3550 return true; 3551 3552 abfd = info->input_bfds; 3553 size = info->cache_size; 3554 do 3555 { 3556 if (size >= info->max_cache_size) 3557 { 3558 /* Over the limit. Reduce the memory usage. */ 3559 info->keep_memory = false; 3560 return false; 3561 } 3562 if (!abfd) 3563 break; 3564 size += abfd->alloc_size; 3565 abfd = abfd->link.next; 3566 } 3567 while (1); 3568 3569 return true; 3570 } 3571