1 /* bfdlink.h -- header file for BFD link routines 2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 3 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. 4 Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support. 5 6 This file is part of BFD, the Binary File Descriptor library. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 21 MA 02110-1301, USA. */ 22 23 #ifndef BFDLINK_H 24 #define BFDLINK_H 25 26 /* Which symbols to strip during a link. */ 27 enum bfd_link_strip 28 { 29 strip_none, /* Don't strip any symbols. */ 30 strip_debugger, /* Strip debugging symbols. */ 31 strip_some, /* keep_hash is the list of symbols to keep. */ 32 strip_all /* Strip all symbols. */ 33 }; 34 35 /* Which local symbols to discard during a link. This is irrelevant 36 if strip_all is used. */ 37 enum bfd_link_discard 38 { 39 discard_sec_merge, /* Discard local temporary symbols in SEC_MERGE 40 sections. */ 41 discard_none, /* Don't discard any locals. */ 42 discard_l, /* Discard local temporary symbols. */ 43 discard_all /* Discard all locals. */ 44 }; 45 46 /* Describes the type of hash table entry structure being used. 47 Different hash table structure have different fields and so 48 support different linking features. */ 49 enum bfd_link_hash_table_type 50 { 51 bfd_link_generic_hash_table, 52 bfd_link_elf_hash_table 53 }; 54 55 /* These are the possible types of an entry in the BFD link hash 56 table. */ 57 58 enum bfd_link_hash_type 59 { 60 bfd_link_hash_new, /* Symbol is new. */ 61 bfd_link_hash_undefined, /* Symbol seen before, but undefined. */ 62 bfd_link_hash_undefweak, /* Symbol is weak and undefined. */ 63 bfd_link_hash_defined, /* Symbol is defined. */ 64 bfd_link_hash_defweak, /* Symbol is weak and defined. */ 65 bfd_link_hash_common, /* Symbol is common. */ 66 bfd_link_hash_indirect, /* Symbol is an indirect link. */ 67 bfd_link_hash_warning /* Like indirect, but warn if referenced. */ 68 }; 69 70 enum bfd_link_common_skip_ar_symbols 71 { 72 bfd_link_common_skip_none, 73 bfd_link_common_skip_text, 74 bfd_link_common_skip_data, 75 bfd_link_common_skip_all 76 }; 77 78 struct bfd_link_hash_common_entry 79 { 80 unsigned int alignment_power; /* Alignment. */ 81 asection *section; /* Symbol section. */ 82 }; 83 84 /* The linking routines use a hash table which uses this structure for 85 its elements. */ 86 87 struct bfd_link_hash_entry 88 { 89 /* Base hash table entry structure. */ 90 struct bfd_hash_entry root; 91 92 /* Type of this entry. */ 93 ENUM_BITFIELD (bfd_link_hash_type) type : 8; 94 95 unsigned int non_ir_ref : 1; 96 97 /* A union of information depending upon the type. */ 98 union 99 { 100 /* Nothing is kept for bfd_hash_new. */ 101 /* bfd_link_hash_undefined, bfd_link_hash_undefweak. */ 102 struct 103 { 104 /* Undefined and common symbols are kept in a linked list through 105 this field. This field is present in all of the union element 106 so that we don't need to remove entries from the list when we 107 change their type. Removing entries would either require the 108 list to be doubly linked, which would waste more memory, or 109 require a traversal. When an undefined or common symbol is 110 created, it should be added to this list, the head of which is in 111 the link hash table itself. As symbols are defined, they need 112 not be removed from the list; anything which reads the list must 113 doublecheck the symbol type. 114 115 Weak symbols are not kept on this list. 116 117 Defined and defweak symbols use this field as a reference marker. 118 If the field is not NULL, or this structure is the tail of the 119 undefined symbol list, the symbol has been referenced. If the 120 symbol is undefined and becomes defined, this field will 121 automatically be non-NULL since the symbol will have been on the 122 undefined symbol list. */ 123 struct bfd_link_hash_entry *next; 124 bfd *abfd; /* BFD symbol was found in. */ 125 } undef; 126 /* bfd_link_hash_defined, bfd_link_hash_defweak. */ 127 struct 128 { 129 struct bfd_link_hash_entry *next; 130 asection *section; /* Symbol section. */ 131 bfd_vma value; /* Symbol value. */ 132 } def; 133 /* bfd_link_hash_indirect, bfd_link_hash_warning. */ 134 struct 135 { 136 struct bfd_link_hash_entry *next; 137 struct bfd_link_hash_entry *link; /* Real symbol. */ 138 const char *warning; /* Warning (bfd_link_hash_warning only). */ 139 } i; 140 /* bfd_link_hash_common. */ 141 struct 142 { 143 struct bfd_link_hash_entry *next; 144 /* The linker needs to know three things about common 145 symbols: the size, the alignment, and the section in 146 which the symbol should be placed. We store the size 147 here, and we allocate a small structure to hold the 148 section and the alignment. The alignment is stored as a 149 power of two. We don't store all the information 150 directly because we don't want to increase the size of 151 the union; this structure is a major space user in the 152 linker. */ 153 struct bfd_link_hash_common_entry *p; 154 bfd_size_type size; /* Common symbol size. */ 155 } c; 156 } u; 157 }; 158 159 /* This is the link hash table. It is a derived class of 160 bfd_hash_table. */ 161 162 struct bfd_link_hash_table 163 { 164 /* The hash table itself. */ 165 struct bfd_hash_table table; 166 /* A linked list of undefined and common symbols, linked through the 167 next field in the bfd_link_hash_entry structure. */ 168 struct bfd_link_hash_entry *undefs; 169 /* Entries are added to the tail of the undefs list. */ 170 struct bfd_link_hash_entry *undefs_tail; 171 /* The type of the link hash table. */ 172 enum bfd_link_hash_table_type type; 173 }; 174 175 /* Look up an entry in a link hash table. If FOLLOW is TRUE, this 176 follows bfd_link_hash_indirect and bfd_link_hash_warning links to 177 the real symbol. */ 178 extern struct bfd_link_hash_entry *bfd_link_hash_lookup 179 (struct bfd_link_hash_table *, const char *, bfd_boolean create, 180 bfd_boolean copy, bfd_boolean follow); 181 182 /* Look up an entry in the main linker hash table if the symbol might 183 be wrapped. This should only be used for references to an 184 undefined symbol, not for definitions of a symbol. */ 185 186 extern struct bfd_link_hash_entry *bfd_wrapped_link_hash_lookup 187 (bfd *, struct bfd_link_info *, const char *, bfd_boolean, 188 bfd_boolean, bfd_boolean); 189 190 /* Traverse a link hash table. */ 191 extern void bfd_link_hash_traverse 192 (struct bfd_link_hash_table *, 193 bfd_boolean (*) (struct bfd_link_hash_entry *, void *), 194 void *); 195 196 /* Add an entry to the undefs list. */ 197 extern void bfd_link_add_undef 198 (struct bfd_link_hash_table *, struct bfd_link_hash_entry *); 199 200 /* Remove symbols from the undefs list that don't belong there. */ 201 extern void bfd_link_repair_undef_list 202 (struct bfd_link_hash_table *table); 203 204 /* Read symbols and cache symbol pointer array in outsymbols. */ 205 extern bfd_boolean bfd_generic_link_read_symbols (bfd *); 206 207 struct bfd_sym_chain 208 { 209 struct bfd_sym_chain *next; 210 const char *name; 211 }; 212 213 /* How to handle unresolved symbols. 214 There are four possibilities which are enumerated below: */ 215 enum report_method 216 { 217 /* This is the initial value when then link_info structure is created. 218 It allows the various stages of the linker to determine whether they 219 allowed to set the value. */ 220 RM_NOT_YET_SET = 0, 221 RM_IGNORE, 222 RM_GENERATE_WARNING, 223 RM_GENERATE_ERROR 224 }; 225 226 struct bfd_elf_dynamic_list; 227 228 /* This structure holds all the information needed to communicate 229 between BFD and the linker when doing a link. */ 230 231 struct bfd_link_info 232 { 233 /* TRUE if BFD should generate a relocatable object file. */ 234 unsigned int relocatable: 1; 235 236 /* TRUE if BFD should generate relocation information in the final 237 executable. */ 238 unsigned int emitrelocations: 1; 239 240 /* TRUE if BFD should generate a "task linked" object file, 241 similar to relocatable but also with globals converted to 242 statics. */ 243 unsigned int task_link: 1; 244 245 /* TRUE if BFD should generate a shared object. */ 246 unsigned int shared: 1; 247 248 /* TRUE if BFD should pre-bind symbols in a shared object. */ 249 unsigned int symbolic: 1; 250 251 /* TRUE if BFD should export all symbols in the dynamic symbol table 252 of an executable, rather than only those used. */ 253 unsigned int export_dynamic: 1; 254 255 /* TRUE if shared objects should be linked directly, not shared. */ 256 unsigned int static_link: 1; 257 258 /* TRUE if the output file should be in a traditional format. This 259 is equivalent to the setting of the BFD_TRADITIONAL_FORMAT flag 260 on the output file, but may be checked when reading the input 261 files. */ 262 unsigned int traditional_format: 1; 263 264 /* TRUE if we want to produced optimized output files. This might 265 need much more time and therefore must be explicitly selected. */ 266 unsigned int optimize: 1; 267 268 /* TRUE if ok to have multiple definition. */ 269 unsigned int allow_multiple_definition: 1; 270 271 /* TRUE if ok to have version with no definition. */ 272 unsigned int allow_undefined_version: 1; 273 274 /* TRUE if a default symbol version should be created and used for 275 exported symbols. */ 276 unsigned int create_default_symver: 1; 277 278 /* TRUE if a default symbol version should be created and used for 279 imported symbols. */ 280 unsigned int default_imported_symver: 1; 281 282 /* TRUE if symbols should be retained in memory, FALSE if they 283 should be freed and reread. */ 284 unsigned int keep_memory: 1; 285 286 /* TRUE if every symbol should be reported back via the notice 287 callback. */ 288 unsigned int notice_all: 1; 289 290 /* TRUE if executable should not contain copy relocs. 291 Setting this true may result in a non-sharable text segment. */ 292 unsigned int nocopyreloc: 1; 293 294 /* TRUE if the new ELF dynamic tags are enabled. */ 295 unsigned int new_dtags: 1; 296 297 /* TRUE if non-PLT relocs should be merged into one reloc section 298 and sorted so that relocs against the same symbol come together. */ 299 unsigned int combreloc: 1; 300 301 /* TRUE if .eh_frame_hdr section and PT_GNU_EH_FRAME ELF segment 302 should be created. */ 303 unsigned int eh_frame_hdr: 1; 304 305 /* TRUE if global symbols in discarded sections should be stripped. */ 306 unsigned int strip_discarded: 1; 307 308 /* TRUE if generating a position independent executable. */ 309 unsigned int pie: 1; 310 311 /* TRUE if generating an executable, position independent or not. */ 312 unsigned int executable : 1; 313 314 /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W|PF_X 315 flags. */ 316 unsigned int execstack: 1; 317 318 /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W 319 flags. */ 320 unsigned int noexecstack: 1; 321 322 /* TRUE if PT_GNU_RELRO segment should be created. */ 323 unsigned int relro: 1; 324 325 /* TRUE if we should warn when adding a DT_TEXTREL to a shared object. */ 326 unsigned int warn_shared_textrel: 1; 327 328 /* TRUE if we should warn alternate ELF machine code. */ 329 unsigned int warn_alternate_em: 1; 330 331 /* TRUE if unreferenced sections should be removed. */ 332 unsigned int gc_sections: 1; 333 334 /* TRUE if user shoudl be informed of removed unreferenced sections. */ 335 unsigned int print_gc_sections: 1; 336 337 /* TRUE if .hash section should be created. */ 338 unsigned int emit_hash: 1; 339 340 /* TRUE if .gnu.hash section should be created. */ 341 unsigned int emit_gnu_hash: 1; 342 343 /* If TRUE reduce memory overheads, at the expense of speed. This will 344 cause map file generation to use an O(N^2) algorithm and disable 345 caching ELF symbol buffer. */ 346 unsigned int reduce_memory_overheads: 1; 347 348 /* TRUE if all data symbols should be dynamic. */ 349 unsigned int dynamic_data: 1; 350 351 /* TRUE if some symbols have to be dynamic, controlled by 352 --dynamic-list command line options. */ 353 unsigned int dynamic: 1; 354 355 /* Non-NULL if .note.gnu.build-id section should be created. */ 356 char *emit_note_gnu_build_id; 357 358 /* What to do with unresolved symbols in an object file. 359 When producing executables the default is GENERATE_ERROR. 360 When producing shared libraries the default is IGNORE. The 361 assumption with shared libraries is that the reference will be 362 resolved at load/execution time. */ 363 enum report_method unresolved_syms_in_objects; 364 365 /* What to do with unresolved symbols in a shared library. 366 The same defaults apply. */ 367 enum report_method unresolved_syms_in_shared_libs; 368 369 /* Which symbols to strip. */ 370 enum bfd_link_strip strip; 371 372 /* Which local symbols to discard. */ 373 enum bfd_link_discard discard; 374 375 /* Criteria for skipping symbols when determining 376 whether to include an object from an archive. */ 377 enum bfd_link_common_skip_ar_symbols common_skip_ar_symbols; 378 379 /* Char that may appear as the first char of a symbol, but should be 380 skipped (like symbol_leading_char) when looking up symbols in 381 wrap_hash. Used by PowerPC Linux for 'dot' symbols. */ 382 char wrap_char; 383 384 /* Separator between archive and filename in linker script filespecs. */ 385 char path_separator; 386 387 /* Function callbacks. */ 388 const struct bfd_link_callbacks *callbacks; 389 390 /* Hash table handled by BFD. */ 391 struct bfd_link_hash_table *hash; 392 393 /* Hash table of symbols to keep. This is NULL unless strip is 394 strip_some. */ 395 struct bfd_hash_table *keep_hash; 396 397 /* Hash table of symbols to report back via the notice callback. If 398 this is NULL, and notice_all is FALSE, then no symbols are 399 reported back. */ 400 struct bfd_hash_table *notice_hash; 401 402 /* Hash table of symbols which are being wrapped (the --wrap linker 403 option). If this is NULL, no symbols are being wrapped. */ 404 struct bfd_hash_table *wrap_hash; 405 406 /* Hash table of symbols which may be left unresolved during 407 a link. If this is NULL, no symbols can be left unresolved. */ 408 struct bfd_hash_table *ignore_hash; 409 410 /* The output BFD. */ 411 bfd *output_bfd; 412 413 /* The list of input BFD's involved in the link. These are chained 414 together via the link_next field. */ 415 bfd *input_bfds; 416 bfd **input_bfds_tail; 417 418 /* If a symbol should be created for each input BFD, this is section 419 where those symbols should be placed. It must be a section in 420 the output BFD. It may be NULL, in which case no such symbols 421 will be created. This is to support CREATE_OBJECT_SYMBOLS in the 422 linker command language. */ 423 asection *create_object_symbols_section; 424 425 /* List of global symbol names that are starting points for marking 426 sections against garbage collection. */ 427 struct bfd_sym_chain *gc_sym_list; 428 429 /* If a base output file is wanted, then this points to it */ 430 void *base_file; 431 432 /* The function to call when the executable or shared object is 433 loaded. */ 434 const char *init_function; 435 436 /* The function to call when the executable or shared object is 437 unloaded. */ 438 const char *fini_function; 439 440 /* Number of relaxation passes. Usually only one relaxation pass 441 is needed. But a backend can have as many relaxation passes as 442 necessary. During bfd_relax_section call, it is set to the 443 current pass, starting from 0. */ 444 int relax_pass; 445 446 /* Number of relaxation trips. This number is incremented every 447 time the relaxation pass is restarted due to a previous 448 relaxation returning true in *AGAIN. */ 449 int relax_trip; 450 451 /* Non-zero if auto-import thunks for DATA items in pei386 DLLs 452 should be generated/linked against. Set to 1 if this feature 453 is explicitly requested by the user, -1 if enabled by default. */ 454 int pei386_auto_import; 455 456 /* Non-zero if runtime relocs for DATA items with non-zero addends 457 in pei386 DLLs should be generated. Set to 1 if this feature 458 is explicitly requested by the user, -1 if enabled by default. */ 459 int pei386_runtime_pseudo_reloc; 460 461 /* How many spare .dynamic DT_NULL entries should be added? */ 462 unsigned int spare_dynamic_tags; 463 464 /* May be used to set DT_FLAGS for ELF. */ 465 bfd_vma flags; 466 467 /* May be used to set DT_FLAGS_1 for ELF. */ 468 bfd_vma flags_1; 469 470 /* Start and end of RELRO region. */ 471 bfd_vma relro_start, relro_end; 472 473 /* List of symbols should be dynamic. */ 474 struct bfd_elf_dynamic_list *dynamic_list; 475 }; 476 477 /* This structures holds a set of callback functions. These are called 478 by the BFD linker routines. Except for the info functions, the first 479 argument to each callback function is the bfd_link_info structure 480 being used and each function returns a boolean value. If the 481 function returns FALSE, then the BFD function which called it should 482 return with a failure indication. */ 483 484 struct bfd_link_callbacks 485 { 486 /* A function which is called when an object is added from an 487 archive. ABFD is the archive element being added. NAME is the 488 name of the symbol which caused the archive element to be pulled 489 in. This function may set *SUBSBFD to point to an alternative 490 BFD from which symbols should in fact be added in place of the 491 original BFD's symbols. */ 492 bfd_boolean (*add_archive_element) 493 (struct bfd_link_info *, bfd *abfd, const char *name, bfd **subsbfd); 494 /* A function which is called when a symbol is found with multiple 495 definitions. H is the symbol which is defined multiple times. 496 NBFD is the new BFD, NSEC is the new section, and NVAL is the new 497 value. NSEC may be bfd_com_section or bfd_ind_section. */ 498 bfd_boolean (*multiple_definition) 499 (struct bfd_link_info *, struct bfd_link_hash_entry *h, 500 bfd *nbfd, asection *nsec, bfd_vma nval); 501 /* A function which is called when a common symbol is defined 502 multiple times. H is the symbol appearing multiple times. 503 NBFD is the BFD of the new symbol. NTYPE is the type of the new 504 symbol, one of bfd_link_hash_defined, bfd_link_hash_common, or 505 bfd_link_hash_indirect. If NTYPE is bfd_link_hash_common, NSIZE 506 is the size of the new symbol. */ 507 bfd_boolean (*multiple_common) 508 (struct bfd_link_info *, struct bfd_link_hash_entry *h, 509 bfd *nbfd, enum bfd_link_hash_type ntype, bfd_vma nsize); 510 /* A function which is called to add a symbol to a set. ENTRY is 511 the link hash table entry for the set itself (e.g., 512 __CTOR_LIST__). RELOC is the relocation to use for an entry in 513 the set when generating a relocatable file, and is also used to 514 get the size of the entry when generating an executable file. 515 ABFD, SEC and VALUE identify the value to add to the set. */ 516 bfd_boolean (*add_to_set) 517 (struct bfd_link_info *, struct bfd_link_hash_entry *entry, 518 bfd_reloc_code_real_type reloc, bfd *abfd, asection *sec, bfd_vma value); 519 /* A function which is called when the name of a g++ constructor or 520 destructor is found. This is only called by some object file 521 formats. CONSTRUCTOR is TRUE for a constructor, FALSE for a 522 destructor. This will use BFD_RELOC_CTOR when generating a 523 relocatable file. NAME is the name of the symbol found. ABFD, 524 SECTION and VALUE are the value of the symbol. */ 525 bfd_boolean (*constructor) 526 (struct bfd_link_info *, bfd_boolean constructor, const char *name, 527 bfd *abfd, asection *sec, bfd_vma value); 528 /* A function which is called to issue a linker warning. For 529 example, this is called when there is a reference to a warning 530 symbol. WARNING is the warning to be issued. SYMBOL is the name 531 of the symbol which triggered the warning; it may be NULL if 532 there is none. ABFD, SECTION and ADDRESS identify the location 533 which trigerred the warning; either ABFD or SECTION or both may 534 be NULL if the location is not known. */ 535 bfd_boolean (*warning) 536 (struct bfd_link_info *, const char *warning, const char *symbol, 537 bfd *abfd, asection *section, bfd_vma address); 538 /* A function which is called when a relocation is attempted against 539 an undefined symbol. NAME is the symbol which is undefined. 540 ABFD, SECTION and ADDRESS identify the location from which the 541 reference is made. IS_FATAL indicates whether an undefined symbol is 542 a fatal error or not. In some cases SECTION may be NULL. */ 543 bfd_boolean (*undefined_symbol) 544 (struct bfd_link_info *, const char *name, bfd *abfd, 545 asection *section, bfd_vma address, bfd_boolean is_fatal); 546 /* A function which is called when a reloc overflow occurs. ENTRY is 547 the link hash table entry for the symbol the reloc is against. 548 NAME is the name of the local symbol or section the reloc is 549 against, RELOC_NAME is the name of the relocation, and ADDEND is 550 any addend that is used. ABFD, SECTION and ADDRESS identify the 551 location at which the overflow occurs; if this is the result of a 552 bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then 553 ABFD will be NULL. */ 554 bfd_boolean (*reloc_overflow) 555 (struct bfd_link_info *, struct bfd_link_hash_entry *entry, 556 const char *name, const char *reloc_name, bfd_vma addend, 557 bfd *abfd, asection *section, bfd_vma address); 558 /* A function which is called when a dangerous reloc is performed. 559 MESSAGE is an appropriate message. 560 ABFD, SECTION and ADDRESS identify the location at which the 561 problem occurred; if this is the result of a 562 bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then 563 ABFD will be NULL. */ 564 bfd_boolean (*reloc_dangerous) 565 (struct bfd_link_info *, const char *message, 566 bfd *abfd, asection *section, bfd_vma address); 567 /* A function which is called when a reloc is found to be attached 568 to a symbol which is not being written out. NAME is the name of 569 the symbol. ABFD, SECTION and ADDRESS identify the location of 570 the reloc; if this is the result of a 571 bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then 572 ABFD will be NULL. */ 573 bfd_boolean (*unattached_reloc) 574 (struct bfd_link_info *, const char *name, 575 bfd *abfd, asection *section, bfd_vma address); 576 /* A function which is called when a symbol in notice_hash is 577 defined or referenced. H is the symbol. ABFD, SECTION and 578 ADDRESS are the (new) value of the symbol. If SECTION is 579 bfd_und_section, this is a reference. FLAGS are the symbol 580 BSF_* flags. STRING is the name of the symbol to indirect to if 581 the sym is indirect, or the warning string if a warning sym. */ 582 bfd_boolean (*notice) 583 (struct bfd_link_info *, struct bfd_link_hash_entry *h, 584 bfd *abfd, asection *section, bfd_vma address, flagword flags, 585 const char *string); 586 /* Error or warning link info message. */ 587 void (*einfo) 588 (const char *fmt, ...); 589 /* General link info message. */ 590 void (*info) 591 (const char *fmt, ...); 592 /* Message to be printed in linker map file. */ 593 void (*minfo) 594 (const char *fmt, ...); 595 /* This callback provides a chance for users of the BFD library to 596 override its decision about whether to place two adjacent sections 597 into the same segment. */ 598 bfd_boolean (*override_segment_assignment) 599 (struct bfd_link_info *, bfd * abfd, 600 asection * current_section, asection * previous_section, 601 bfd_boolean new_segment); 602 }; 603 604 /* The linker builds link_order structures which tell the code how to 605 include input data in the output file. */ 606 607 /* These are the types of link_order structures. */ 608 609 enum bfd_link_order_type 610 { 611 bfd_undefined_link_order, /* Undefined. */ 612 bfd_indirect_link_order, /* Built from a section. */ 613 bfd_data_link_order, /* Set to explicit data. */ 614 bfd_section_reloc_link_order, /* Relocate against a section. */ 615 bfd_symbol_reloc_link_order /* Relocate against a symbol. */ 616 }; 617 618 /* This is the link_order structure itself. These form a chain 619 attached to the output section whose contents they are describing. */ 620 621 struct bfd_link_order 622 { 623 /* Next link_order in chain. */ 624 struct bfd_link_order *next; 625 /* Type of link_order. */ 626 enum bfd_link_order_type type; 627 /* Offset within output section. */ 628 bfd_vma offset; 629 /* Size within output section. */ 630 bfd_size_type size; 631 /* Type specific information. */ 632 union 633 { 634 struct 635 { 636 /* Section to include. If this is used, then 637 section->output_section must be the section the 638 link_order is attached to, section->output_offset must 639 equal the link_order offset field, and section->size 640 must equal the link_order size field. Maybe these 641 restrictions should be relaxed someday. */ 642 asection *section; 643 } indirect; 644 struct 645 { 646 /* Size of contents, or zero when contents size == size 647 within output section. 648 A non-zero value allows filling of the output section 649 with an arbitrary repeated pattern. */ 650 unsigned int size; 651 /* Data to put into file. */ 652 bfd_byte *contents; 653 } data; 654 struct 655 { 656 /* Description of reloc to generate. Used for 657 bfd_section_reloc_link_order and 658 bfd_symbol_reloc_link_order. */ 659 struct bfd_link_order_reloc *p; 660 } reloc; 661 } u; 662 }; 663 664 /* A linker order of type bfd_section_reloc_link_order or 665 bfd_symbol_reloc_link_order means to create a reloc against a 666 section or symbol, respectively. This is used to implement -Ur to 667 generate relocs for the constructor tables. The 668 bfd_link_order_reloc structure describes the reloc that BFD should 669 create. It is similar to a arelent, but I didn't use arelent 670 because the linker does not know anything about most symbols, and 671 any asymbol structure it creates will be partially meaningless. 672 This information could logically be in the bfd_link_order struct, 673 but I didn't want to waste the space since these types of relocs 674 are relatively rare. */ 675 676 struct bfd_link_order_reloc 677 { 678 /* Reloc type. */ 679 bfd_reloc_code_real_type reloc; 680 681 union 682 { 683 /* For type bfd_section_reloc_link_order, this is the section 684 the reloc should be against. This must be a section in the 685 output BFD, not any of the input BFDs. */ 686 asection *section; 687 /* For type bfd_symbol_reloc_link_order, this is the name of the 688 symbol the reloc should be against. */ 689 const char *name; 690 } u; 691 692 /* Addend to use. The object file should contain zero. The BFD 693 backend is responsible for filling in the contents of the object 694 file correctly. For some object file formats (e.g., COFF) the 695 addend must be stored into in the object file, and for some 696 (e.g., SPARC a.out) it is kept in the reloc. */ 697 bfd_vma addend; 698 }; 699 700 /* Allocate a new link_order for a section. */ 701 extern struct bfd_link_order *bfd_new_link_order (bfd *, asection *); 702 703 /* These structures are used to describe version information for the 704 ELF linker. These structures could be manipulated entirely inside 705 BFD, but it would be a pain. Instead, the regular linker sets up 706 these structures, and then passes them into BFD. */ 707 708 /* Glob pattern for a version. */ 709 710 struct bfd_elf_version_expr 711 { 712 /* Next glob pattern for this version. */ 713 struct bfd_elf_version_expr *next; 714 /* Glob pattern. */ 715 const char *pattern; 716 /* Set if pattern is not a glob. */ 717 unsigned int literal : 1; 718 /* Defined by ".symver". */ 719 unsigned int symver : 1; 720 /* Defined by version script. */ 721 unsigned int script : 1; 722 /* Pattern type. */ 723 #define BFD_ELF_VERSION_C_TYPE 1 724 #define BFD_ELF_VERSION_CXX_TYPE 2 725 #define BFD_ELF_VERSION_JAVA_TYPE 4 726 unsigned int mask : 3; 727 }; 728 729 struct bfd_elf_version_expr_head 730 { 731 /* List of all patterns, both wildcards and non-wildcards. */ 732 struct bfd_elf_version_expr *list; 733 /* Hash table for non-wildcards. */ 734 void *htab; 735 /* Remaining patterns. */ 736 struct bfd_elf_version_expr *remaining; 737 /* What kind of pattern types are present in list (bitmask). */ 738 unsigned int mask; 739 }; 740 741 /* Version dependencies. */ 742 743 struct bfd_elf_version_deps 744 { 745 /* Next dependency for this version. */ 746 struct bfd_elf_version_deps *next; 747 /* The version which this version depends upon. */ 748 struct bfd_elf_version_tree *version_needed; 749 }; 750 751 /* A node in the version tree. */ 752 753 struct bfd_elf_version_tree 754 { 755 /* Next version. */ 756 struct bfd_elf_version_tree *next; 757 /* Name of this version. */ 758 const char *name; 759 /* Version number. */ 760 unsigned int vernum; 761 /* Regular expressions for global symbols in this version. */ 762 struct bfd_elf_version_expr_head globals; 763 /* Regular expressions for local symbols in this version. */ 764 struct bfd_elf_version_expr_head locals; 765 /* List of versions which this version depends upon. */ 766 struct bfd_elf_version_deps *deps; 767 /* Index of the version name. This is used within BFD. */ 768 unsigned int name_indx; 769 /* Whether this version tree was used. This is used within BFD. */ 770 int used; 771 /* Matching hook. */ 772 struct bfd_elf_version_expr *(*match) 773 (struct bfd_elf_version_expr_head *head, 774 struct bfd_elf_version_expr *prev, const char *sym); 775 }; 776 777 struct bfd_elf_dynamic_list 778 { 779 struct bfd_elf_version_expr_head head; 780 struct bfd_elf_version_expr *(*match) 781 (struct bfd_elf_version_expr_head *head, 782 struct bfd_elf_version_expr *prev, const char *sym); 783 }; 784 785 #endif 786