Commit | Line | Data |
---|---|---|
252b5132 | 1 | /* bfdlink.h -- header file for BFD link routines |
c3aa17e9 | 2 | Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, |
24f58f47 AM |
3 | 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 |
4 | Free Software Foundation, Inc. | |
252b5132 RH |
5 | Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support. |
6 | ||
e0076ab3 | 7 | This file is part of BFD, the Binary File Descriptor library. |
252b5132 | 8 | |
e0076ab3 NC |
9 | This program is free software; you can redistribute it and/or modify |
10 | it under the terms of the GNU General Public License as published by | |
a208b53c | 11 | the Free Software Foundation; either version 3 of the License, or |
e0076ab3 | 12 | (at your option) any later version. |
252b5132 | 13 | |
e0076ab3 NC |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
252b5132 | 18 | |
e0076ab3 NC |
19 | You should have received a copy of the GNU General Public License |
20 | along with this program; if not, write to the Free Software | |
a208b53c NC |
21 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
22 | MA 02110-1301, USA. */ | |
252b5132 RH |
23 | |
24 | #ifndef BFDLINK_H | |
25 | #define BFDLINK_H | |
26 | ||
27 | /* Which symbols to strip during a link. */ | |
28 | enum bfd_link_strip | |
29 | { | |
30 | strip_none, /* Don't strip any symbols. */ | |
31 | strip_debugger, /* Strip debugging symbols. */ | |
32 | strip_some, /* keep_hash is the list of symbols to keep. */ | |
33 | strip_all /* Strip all symbols. */ | |
34 | }; | |
35 | ||
36 | /* Which local symbols to discard during a link. This is irrelevant | |
37 | if strip_all is used. */ | |
38 | enum bfd_link_discard | |
39 | { | |
f5fa8ca2 JJ |
40 | discard_sec_merge, /* Discard local temporary symbols in SEC_MERGE |
41 | sections. */ | |
252b5132 RH |
42 | discard_none, /* Don't discard any locals. */ |
43 | discard_l, /* Discard local temporary symbols. */ | |
44 | discard_all /* Discard all locals. */ | |
45 | }; | |
8ea2e4bd NC |
46 | |
47 | /* Describes the type of hash table entry structure being used. | |
48 | Different hash table structure have different fields and so | |
49 | support different linking features. */ | |
50 | enum bfd_link_hash_table_type | |
51 | { | |
52 | bfd_link_generic_hash_table, | |
53 | bfd_link_elf_hash_table | |
54 | }; | |
252b5132 RH |
55 | \f |
56 | /* These are the possible types of an entry in the BFD link hash | |
57 | table. */ | |
58 | ||
59 | enum bfd_link_hash_type | |
60 | { | |
61 | bfd_link_hash_new, /* Symbol is new. */ | |
62 | bfd_link_hash_undefined, /* Symbol seen before, but undefined. */ | |
63 | bfd_link_hash_undefweak, /* Symbol is weak and undefined. */ | |
64 | bfd_link_hash_defined, /* Symbol is defined. */ | |
65 | bfd_link_hash_defweak, /* Symbol is weak and defined. */ | |
66 | bfd_link_hash_common, /* Symbol is common. */ | |
67 | bfd_link_hash_indirect, /* Symbol is an indirect link. */ | |
68 | bfd_link_hash_warning /* Like indirect, but warn if referenced. */ | |
69 | }; | |
70 | ||
f88dc410 | 71 | enum bfd_link_common_skip_ar_symbols |
f7c33884 NC |
72 | { |
73 | bfd_link_common_skip_none, | |
74 | bfd_link_common_skip_text, | |
75 | bfd_link_common_skip_data, | |
76 | bfd_link_common_skip_all | |
77 | }; | |
78 | ||
a50b1753 NC |
79 | struct bfd_link_hash_common_entry |
80 | { | |
81 | unsigned int alignment_power; /* Alignment. */ | |
82 | asection *section; /* Symbol section. */ | |
83 | }; | |
84 | ||
252b5132 RH |
85 | /* The linking routines use a hash table which uses this structure for |
86 | its elements. */ | |
87 | ||
88 | struct bfd_link_hash_entry | |
89 | { | |
90 | /* Base hash table entry structure. */ | |
91 | struct bfd_hash_entry root; | |
6ad841a1 | 92 | |
252b5132 | 93 | /* Type of this entry. */ |
35ed3f94 AM |
94 | ENUM_BITFIELD (bfd_link_hash_type) type : 8; |
95 | ||
96 | unsigned int non_ir_ref : 1; | |
252b5132 | 97 | |
252b5132 RH |
98 | /* A union of information depending upon the type. */ |
99 | union | |
100 | { | |
101 | /* Nothing is kept for bfd_hash_new. */ | |
102 | /* bfd_link_hash_undefined, bfd_link_hash_undefweak. */ | |
103 | struct | |
104 | { | |
f6e332e6 AM |
105 | /* Undefined and common symbols are kept in a linked list through |
106 | this field. This field is present in all of the union element | |
107 | so that we don't need to remove entries from the list when we | |
108 | change their type. Removing entries would either require the | |
109 | list to be doubly linked, which would waste more memory, or | |
110 | require a traversal. When an undefined or common symbol is | |
111 | created, it should be added to this list, the head of which is in | |
112 | the link hash table itself. As symbols are defined, they need | |
113 | not be removed from the list; anything which reads the list must | |
114 | doublecheck the symbol type. | |
115 | ||
116 | Weak symbols are not kept on this list. | |
117 | ||
118 | Defined and defweak symbols use this field as a reference marker. | |
119 | If the field is not NULL, or this structure is the tail of the | |
120 | undefined symbol list, the symbol has been referenced. If the | |
121 | symbol is undefined and becomes defined, this field will | |
122 | automatically be non-NULL since the symbol will have been on the | |
123 | undefined symbol list. */ | |
124 | struct bfd_link_hash_entry *next; | |
252b5132 RH |
125 | bfd *abfd; /* BFD symbol was found in. */ |
126 | } undef; | |
127 | /* bfd_link_hash_defined, bfd_link_hash_defweak. */ | |
128 | struct | |
129 | { | |
f6e332e6 | 130 | struct bfd_link_hash_entry *next; |
252b5132 | 131 | asection *section; /* Symbol section. */ |
f6e332e6 | 132 | bfd_vma value; /* Symbol value. */ |
252b5132 RH |
133 | } def; |
134 | /* bfd_link_hash_indirect, bfd_link_hash_warning. */ | |
135 | struct | |
136 | { | |
f6e332e6 | 137 | struct bfd_link_hash_entry *next; |
252b5132 RH |
138 | struct bfd_link_hash_entry *link; /* Real symbol. */ |
139 | const char *warning; /* Warning (bfd_link_hash_warning only). */ | |
140 | } i; | |
141 | /* bfd_link_hash_common. */ | |
142 | struct | |
143 | { | |
f6e332e6 | 144 | struct bfd_link_hash_entry *next; |
252b5132 | 145 | /* The linker needs to know three things about common |
b34976b6 AM |
146 | symbols: the size, the alignment, and the section in |
147 | which the symbol should be placed. We store the size | |
148 | here, and we allocate a small structure to hold the | |
149 | section and the alignment. The alignment is stored as a | |
150 | power of two. We don't store all the information | |
151 | directly because we don't want to increase the size of | |
152 | the union; this structure is a major space user in the | |
153 | linker. */ | |
a50b1753 | 154 | struct bfd_link_hash_common_entry *p; |
f6e332e6 | 155 | bfd_size_type size; /* Common symbol size. */ |
252b5132 RH |
156 | } c; |
157 | } u; | |
158 | }; | |
159 | ||
160 | /* This is the link hash table. It is a derived class of | |
161 | bfd_hash_table. */ | |
162 | ||
163 | struct bfd_link_hash_table | |
164 | { | |
165 | /* The hash table itself. */ | |
166 | struct bfd_hash_table table; | |
252b5132 RH |
167 | /* A linked list of undefined and common symbols, linked through the |
168 | next field in the bfd_link_hash_entry structure. */ | |
169 | struct bfd_link_hash_entry *undefs; | |
170 | /* Entries are added to the tail of the undefs list. */ | |
171 | struct bfd_link_hash_entry *undefs_tail; | |
b9b171fb | 172 | /* The type of the link hash table. */ |
8ea2e4bd | 173 | enum bfd_link_hash_table_type type; |
252b5132 RH |
174 | }; |
175 | ||
b34976b6 | 176 | /* Look up an entry in a link hash table. If FOLLOW is TRUE, this |
252b5132 RH |
177 | follows bfd_link_hash_indirect and bfd_link_hash_warning links to |
178 | the real symbol. */ | |
179 | extern struct bfd_link_hash_entry *bfd_link_hash_lookup | |
8cf3f354 AM |
180 | (struct bfd_link_hash_table *, const char *, bfd_boolean create, |
181 | bfd_boolean copy, bfd_boolean follow); | |
252b5132 RH |
182 | |
183 | /* Look up an entry in the main linker hash table if the symbol might | |
184 | be wrapped. This should only be used for references to an | |
185 | undefined symbol, not for definitions of a symbol. */ | |
186 | ||
187 | extern struct bfd_link_hash_entry *bfd_wrapped_link_hash_lookup | |
8cf3f354 AM |
188 | (bfd *, struct bfd_link_info *, const char *, bfd_boolean, |
189 | bfd_boolean, bfd_boolean); | |
252b5132 RH |
190 | |
191 | /* Traverse a link hash table. */ | |
192 | extern void bfd_link_hash_traverse | |
8cf3f354 AM |
193 | (struct bfd_link_hash_table *, |
194 | bfd_boolean (*) (struct bfd_link_hash_entry *, void *), | |
195 | void *); | |
252b5132 RH |
196 | |
197 | /* Add an entry to the undefs list. */ | |
198 | extern void bfd_link_add_undef | |
8cf3f354 | 199 | (struct bfd_link_hash_table *, struct bfd_link_hash_entry *); |
7815cf4f | 200 | |
77cfaee6 AM |
201 | /* Remove symbols from the undefs list that don't belong there. */ |
202 | extern void bfd_link_repair_undef_list | |
203 | (struct bfd_link_hash_table *table); | |
204 | ||
5c1d2f5f AM |
205 | /* Read symbols and cache symbol pointer array in outsymbols. */ |
206 | extern bfd_boolean bfd_generic_link_read_symbols (bfd *); | |
207 | ||
7815cf4f AM |
208 | struct bfd_sym_chain |
209 | { | |
210 | struct bfd_sym_chain *next; | |
211 | const char *name; | |
212 | }; | |
252b5132 | 213 | \f |
560e09e9 NC |
214 | /* How to handle unresolved symbols. |
215 | There are four possibilities which are enumerated below: */ | |
216 | enum report_method | |
217 | { | |
218 | /* This is the initial value when then link_info structure is created. | |
219 | It allows the various stages of the linker to determine whether they | |
220 | allowed to set the value. */ | |
221 | RM_NOT_YET_SET = 0, | |
222 | RM_IGNORE, | |
223 | RM_GENERATE_WARNING, | |
224 | RM_GENERATE_ERROR | |
225 | }; | |
226 | ||
55255dae L |
227 | struct bfd_elf_dynamic_list; |
228 | ||
252b5132 RH |
229 | /* This structure holds all the information needed to communicate |
230 | between BFD and the linker when doing a link. */ | |
231 | ||
232 | struct bfd_link_info | |
233 | { | |
cddd0089 | 234 | /* TRUE if BFD should generate a relocatable object file. */ |
1049f94e | 235 | unsigned int relocatable: 1; |
7815cf4f | 236 | |
b34976b6 | 237 | /* TRUE if BFD should generate relocation information in the final |
7815cf4f | 238 | executable. */ |
cddd0089 | 239 | unsigned int emitrelocations: 1; |
7815cf4f | 240 | |
b34976b6 | 241 | /* TRUE if BFD should generate a "task linked" object file, |
7815cf4f AM |
242 | similar to relocatable but also with globals converted to |
243 | statics. */ | |
cddd0089 | 244 | unsigned int task_link: 1; |
7815cf4f | 245 | |
b34976b6 | 246 | /* TRUE if BFD should generate a shared object. */ |
cddd0089 | 247 | unsigned int shared: 1; |
7815cf4f | 248 | |
b34976b6 | 249 | /* TRUE if BFD should pre-bind symbols in a shared object. */ |
cddd0089 | 250 | unsigned int symbolic: 1; |
7815cf4f | 251 | |
b34976b6 | 252 | /* TRUE if BFD should export all symbols in the dynamic symbol table |
7be4069c | 253 | of an executable, rather than only those used. */ |
cddd0089 | 254 | unsigned int export_dynamic: 1; |
7815cf4f | 255 | |
b34976b6 | 256 | /* TRUE if shared objects should be linked directly, not shared. */ |
cddd0089 | 257 | unsigned int static_link: 1; |
7815cf4f | 258 | |
b34976b6 | 259 | /* TRUE if the output file should be in a traditional format. This |
252b5132 RH |
260 | is equivalent to the setting of the BFD_TRADITIONAL_FORMAT flag |
261 | on the output file, but may be checked when reading the input | |
262 | files. */ | |
cddd0089 | 263 | unsigned int traditional_format: 1; |
7815cf4f | 264 | |
b34976b6 | 265 | /* TRUE if we want to produced optimized output files. This might |
252b5132 | 266 | need much more time and therefore must be explicitly selected. */ |
cddd0089 | 267 | unsigned int optimize: 1; |
7815cf4f | 268 | |
b34976b6 | 269 | /* TRUE if ok to have multiple definition. */ |
cddd0089 | 270 | unsigned int allow_multiple_definition: 1; |
7815cf4f | 271 | |
b34976b6 | 272 | /* TRUE if ok to have version with no definition. */ |
cddd0089 AM |
273 | unsigned int allow_undefined_version: 1; |
274 | ||
fc0e6df6 PB |
275 | /* TRUE if a default symbol version should be created and used for |
276 | exported symbols. */ | |
3e3b46e5 PB |
277 | unsigned int create_default_symver: 1; |
278 | ||
fc0e6df6 PB |
279 | /* TRUE if a default symbol version should be created and used for |
280 | imported symbols. */ | |
281 | unsigned int default_imported_symver: 1; | |
282 | ||
cddd0089 AM |
283 | /* TRUE if symbols should be retained in memory, FALSE if they |
284 | should be freed and reread. */ | |
285 | unsigned int keep_memory: 1; | |
286 | ||
287 | /* TRUE if every symbol should be reported back via the notice | |
288 | callback. */ | |
289 | unsigned int notice_all: 1; | |
290 | ||
291 | /* TRUE if executable should not contain copy relocs. | |
292 | Setting this true may result in a non-sharable text segment. */ | |
293 | unsigned int nocopyreloc: 1; | |
294 | ||
295 | /* TRUE if the new ELF dynamic tags are enabled. */ | |
296 | unsigned int new_dtags: 1; | |
297 | ||
298 | /* TRUE if non-PLT relocs should be merged into one reloc section | |
299 | and sorted so that relocs against the same symbol come together. */ | |
300 | unsigned int combreloc: 1; | |
301 | ||
302 | /* TRUE if .eh_frame_hdr section and PT_GNU_EH_FRAME ELF segment | |
303 | should be created. */ | |
304 | unsigned int eh_frame_hdr: 1; | |
31941635 | 305 | |
c6b64018 AM |
306 | /* TRUE if global symbols in discarded sections should be stripped. */ |
307 | unsigned int strip_discarded: 1; | |
308 | ||
36af4a4e JJ |
309 | /* TRUE if generating a position independent executable. */ |
310 | unsigned int pie: 1; | |
311 | ||
312 | /* TRUE if generating an executable, position independent or not. */ | |
313 | unsigned int executable : 1; | |
314 | ||
9ee5e499 JJ |
315 | /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W|PF_X |
316 | flags. */ | |
317 | unsigned int execstack: 1; | |
318 | ||
319 | /* TRUE if PT_GNU_STACK segment should be created with PF_R|PF_W | |
320 | flags. */ | |
321 | unsigned int noexecstack: 1; | |
322 | ||
8c37241b JJ |
323 | /* TRUE if PT_GNU_RELRO segment should be created. */ |
324 | unsigned int relro: 1; | |
325 | ||
8fdd7217 NC |
326 | /* TRUE if we should warn when adding a DT_TEXTREL to a shared object. */ |
327 | unsigned int warn_shared_textrel: 1; | |
328 | ||
a0c402a5 L |
329 | /* TRUE if we should warn alternate ELF machine code. */ |
330 | unsigned int warn_alternate_em: 1; | |
331 | ||
57316bff L |
332 | /* TRUE if unreferenced sections should be removed. */ |
333 | unsigned int gc_sections: 1; | |
334 | ||
c17d87de NC |
335 | /* TRUE if user shoudl be informed of removed unreferenced sections. */ |
336 | unsigned int print_gc_sections: 1; | |
337 | ||
fdc90cb4 JJ |
338 | /* TRUE if .hash section should be created. */ |
339 | unsigned int emit_hash: 1; | |
340 | ||
341 | /* TRUE if .gnu.hash section should be created. */ | |
342 | unsigned int emit_gnu_hash: 1; | |
343 | ||
c0f00686 L |
344 | /* If TRUE reduce memory overheads, at the expense of speed. This will |
345 | cause map file generation to use an O(N^2) algorithm and disable | |
346 | caching ELF symbol buffer. */ | |
347 | unsigned int reduce_memory_overheads: 1; | |
348 | ||
40b36307 L |
349 | /* TRUE if all data symbols should be dynamic. */ |
350 | unsigned int dynamic_data: 1; | |
351 | ||
352 | /* TRUE if some symbols have to be dynamic, controlled by | |
353 | --dynamic-list command line options. */ | |
354 | unsigned int dynamic: 1; | |
355 | ||
e41b3a13 JJ |
356 | /* FALSE if .eh_frame unwind info should be generated for PLT and other |
357 | linker created sections, TRUE if it should be omitted. */ | |
358 | unsigned int no_ld_generated_unwind_info: 1; | |
359 | ||
ab24bc21 RM |
360 | /* Non-NULL if .note.gnu.build-id section should be created. */ |
361 | char *emit_note_gnu_build_id; | |
362 | ||
560e09e9 | 363 | /* What to do with unresolved symbols in an object file. |
59c2e50f L |
364 | When producing executables the default is GENERATE_ERROR. |
365 | When producing shared libraries the default is IGNORE. The | |
366 | assumption with shared libraries is that the reference will be | |
560e09e9 NC |
367 | resolved at load/execution time. */ |
368 | enum report_method unresolved_syms_in_objects; | |
369 | ||
370 | /* What to do with unresolved symbols in a shared library. | |
371 | The same defaults apply. */ | |
372 | enum report_method unresolved_syms_in_shared_libs; | |
373 | ||
252b5132 RH |
374 | /* Which symbols to strip. */ |
375 | enum bfd_link_strip strip; | |
7815cf4f | 376 | |
252b5132 RH |
377 | /* Which local symbols to discard. */ |
378 | enum bfd_link_discard discard; | |
7815cf4f | 379 | |
f88dc410 | 380 | /* Criteria for skipping symbols when determining |
cddd0089 | 381 | whether to include an object from an archive. */ |
f88dc410 | 382 | enum bfd_link_common_skip_ar_symbols common_skip_ar_symbols; |
7815cf4f | 383 | |
b9cf773d AM |
384 | /* Char that may appear as the first char of a symbol, but should be |
385 | skipped (like symbol_leading_char) when looking up symbols in | |
386 | wrap_hash. Used by PowerPC Linux for 'dot' symbols. */ | |
387 | char wrap_char; | |
388 | ||
97407faf AM |
389 | /* Separator between archive and filename in linker script filespecs. */ |
390 | char path_separator; | |
391 | ||
cddd0089 AM |
392 | /* Function callbacks. */ |
393 | const struct bfd_link_callbacks *callbacks; | |
7815cf4f | 394 | |
252b5132 RH |
395 | /* Hash table handled by BFD. */ |
396 | struct bfd_link_hash_table *hash; | |
7815cf4f | 397 | |
252b5132 RH |
398 | /* Hash table of symbols to keep. This is NULL unless strip is |
399 | strip_some. */ | |
400 | struct bfd_hash_table *keep_hash; | |
7815cf4f | 401 | |
252b5132 | 402 | /* Hash table of symbols to report back via the notice callback. If |
b34976b6 | 403 | this is NULL, and notice_all is FALSE, then no symbols are |
252b5132 RH |
404 | reported back. */ |
405 | struct bfd_hash_table *notice_hash; | |
7815cf4f | 406 | |
252b5132 RH |
407 | /* Hash table of symbols which are being wrapped (the --wrap linker |
408 | option). If this is NULL, no symbols are being wrapped. */ | |
409 | struct bfd_hash_table *wrap_hash; | |
7815cf4f | 410 | |
f13a99db AM |
411 | /* The output BFD. */ |
412 | bfd *output_bfd; | |
413 | ||
cddd0089 AM |
414 | /* The list of input BFD's involved in the link. These are chained |
415 | together via the link_next field. */ | |
416 | bfd *input_bfds; | |
a9a4c53e | 417 | bfd **input_bfds_tail; |
cddd0089 AM |
418 | |
419 | /* If a symbol should be created for each input BFD, this is section | |
420 | where those symbols should be placed. It must be a section in | |
421 | the output BFD. It may be NULL, in which case no such symbols | |
422 | will be created. This is to support CREATE_OBJECT_SYMBOLS in the | |
423 | linker command language. */ | |
424 | asection *create_object_symbols_section; | |
425 | ||
426 | /* List of global symbol names that are starting points for marking | |
427 | sections against garbage collection. */ | |
428 | struct bfd_sym_chain *gc_sym_list; | |
429 | ||
252b5132 | 430 | /* If a base output file is wanted, then this points to it */ |
8cf3f354 | 431 | void *base_file; |
252b5132 | 432 | |
94883c63 MM |
433 | /* The function to call when the executable or shared object is |
434 | loaded. */ | |
435 | const char *init_function; | |
7815cf4f | 436 | |
94883c63 MM |
437 | /* The function to call when the executable or shared object is |
438 | unloaded. */ | |
439 | const char *fini_function; | |
9bfcb6d6 | 440 | |
fbbc3759 L |
441 | /* Number of relaxation passes. Usually only one relaxation pass |
442 | is needed. But a backend can have as many relaxation passes as | |
443 | necessary. During bfd_relax_section call, it is set to the | |
444 | current pass, starting from 0. */ | |
445 | int relax_pass; | |
446 | ||
4a828aab RH |
447 | /* Number of relaxation trips. This number is incremented every |
448 | time the relaxation pass is restarted due to a previous | |
449 | relaxation returning true in *AGAIN. */ | |
450 | int relax_trip; | |
451 | ||
b34976b6 | 452 | /* Non-zero if auto-import thunks for DATA items in pei386 DLLs |
e0076ab3 NC |
453 | should be generated/linked against. Set to 1 if this feature |
454 | is explicitly requested by the user, -1 if enabled by default. */ | |
455 | int pei386_auto_import; | |
db6751f2 | 456 | |
2fa9fc65 NC |
457 | /* Non-zero if runtime relocs for DATA items with non-zero addends |
458 | in pei386 DLLs should be generated. Set to 1 if this feature | |
459 | is explicitly requested by the user, -1 if enabled by default. */ | |
460 | int pei386_runtime_pseudo_reloc; | |
461 | ||
db6751f2 | 462 | /* How many spare .dynamic DT_NULL entries should be added? */ |
b7781dbe | 463 | unsigned int spare_dynamic_tags; |
f7c33884 | 464 | |
cddd0089 AM |
465 | /* May be used to set DT_FLAGS for ELF. */ |
466 | bfd_vma flags; | |
467 | ||
468 | /* May be used to set DT_FLAGS_1 for ELF. */ | |
469 | bfd_vma flags_1; | |
8c37241b JJ |
470 | |
471 | /* Start and end of RELRO region. */ | |
472 | bfd_vma relro_start, relro_end; | |
55255dae L |
473 | |
474 | /* List of symbols should be dynamic. */ | |
40b36307 | 475 | struct bfd_elf_dynamic_list *dynamic_list; |
252b5132 RH |
476 | }; |
477 | ||
49fa1e15 AM |
478 | /* This structures holds a set of callback functions. These are called |
479 | by the BFD linker routines. Except for the info functions, the first | |
e1fffbe6 AM |
480 | argument to each callback function is the bfd_link_info structure |
481 | being used and each function returns a boolean value. If the | |
482 | function returns FALSE, then the BFD function which called it should | |
483 | return with a failure indication. */ | |
252b5132 RH |
484 | |
485 | struct bfd_link_callbacks | |
486 | { | |
487 | /* A function which is called when an object is added from an | |
488 | archive. ABFD is the archive element being added. NAME is the | |
489 | name of the symbol which caused the archive element to be pulled | |
5d3236ee DK |
490 | in. This function may set *SUBSBFD to point to an alternative |
491 | BFD from which symbols should in fact be added in place of the | |
492 | original BFD's symbols. */ | |
b34976b6 | 493 | bfd_boolean (*add_archive_element) |
5d3236ee | 494 | (struct bfd_link_info *, bfd *abfd, const char *name, bfd **subsbfd); |
252b5132 | 495 | /* A function which is called when a symbol is found with multiple |
24f58f47 AM |
496 | definitions. H is the symbol which is defined multiple times. |
497 | NBFD is the new BFD, NSEC is the new section, and NVAL is the new | |
498 | value. NSEC may be bfd_com_section or bfd_ind_section. */ | |
b34976b6 | 499 | bfd_boolean (*multiple_definition) |
24f58f47 | 500 | (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
8cf3f354 | 501 | bfd *nbfd, asection *nsec, bfd_vma nval); |
252b5132 | 502 | /* A function which is called when a common symbol is defined |
24f58f47 | 503 | multiple times. H is the symbol appearing multiple times. |
252b5132 RH |
504 | NBFD is the BFD of the new symbol. NTYPE is the type of the new |
505 | symbol, one of bfd_link_hash_defined, bfd_link_hash_common, or | |
506 | bfd_link_hash_indirect. If NTYPE is bfd_link_hash_common, NSIZE | |
507 | is the size of the new symbol. */ | |
b34976b6 | 508 | bfd_boolean (*multiple_common) |
24f58f47 | 509 | (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
8cf3f354 | 510 | bfd *nbfd, enum bfd_link_hash_type ntype, bfd_vma nsize); |
252b5132 RH |
511 | /* A function which is called to add a symbol to a set. ENTRY is |
512 | the link hash table entry for the set itself (e.g., | |
513 | __CTOR_LIST__). RELOC is the relocation to use for an entry in | |
1049f94e | 514 | the set when generating a relocatable file, and is also used to |
252b5132 RH |
515 | get the size of the entry when generating an executable file. |
516 | ABFD, SEC and VALUE identify the value to add to the set. */ | |
b34976b6 | 517 | bfd_boolean (*add_to_set) |
8cf3f354 AM |
518 | (struct bfd_link_info *, struct bfd_link_hash_entry *entry, |
519 | bfd_reloc_code_real_type reloc, bfd *abfd, asection *sec, bfd_vma value); | |
252b5132 RH |
520 | /* A function which is called when the name of a g++ constructor or |
521 | destructor is found. This is only called by some object file | |
b34976b6 | 522 | formats. CONSTRUCTOR is TRUE for a constructor, FALSE for a |
252b5132 | 523 | destructor. This will use BFD_RELOC_CTOR when generating a |
1049f94e | 524 | relocatable file. NAME is the name of the symbol found. ABFD, |
252b5132 | 525 | SECTION and VALUE are the value of the symbol. */ |
b34976b6 | 526 | bfd_boolean (*constructor) |
8cf3f354 AM |
527 | (struct bfd_link_info *, bfd_boolean constructor, const char *name, |
528 | bfd *abfd, asection *sec, bfd_vma value); | |
252b5132 RH |
529 | /* A function which is called to issue a linker warning. For |
530 | example, this is called when there is a reference to a warning | |
531 | symbol. WARNING is the warning to be issued. SYMBOL is the name | |
532 | of the symbol which triggered the warning; it may be NULL if | |
533 | there is none. ABFD, SECTION and ADDRESS identify the location | |
534 | which trigerred the warning; either ABFD or SECTION or both may | |
535 | be NULL if the location is not known. */ | |
b34976b6 | 536 | bfd_boolean (*warning) |
8cf3f354 AM |
537 | (struct bfd_link_info *, const char *warning, const char *symbol, |
538 | bfd *abfd, asection *section, bfd_vma address); | |
252b5132 RH |
539 | /* A function which is called when a relocation is attempted against |
540 | an undefined symbol. NAME is the symbol which is undefined. | |
541 | ABFD, SECTION and ADDRESS identify the location from which the | |
e7f8eadb | 542 | reference is made. IS_FATAL indicates whether an undefined symbol is |
c086cbc6 | 543 | a fatal error or not. In some cases SECTION may be NULL. */ |
b34976b6 | 544 | bfd_boolean (*undefined_symbol) |
8cf3f354 | 545 | (struct bfd_link_info *, const char *name, bfd *abfd, |
e7f8eadb | 546 | asection *section, bfd_vma address, bfd_boolean is_fatal); |
dfeffb9f L |
547 | /* A function which is called when a reloc overflow occurs. ENTRY is |
548 | the link hash table entry for the symbol the reloc is against. | |
549 | NAME is the name of the local symbol or section the reloc is | |
550 | against, RELOC_NAME is the name of the relocation, and ADDEND is | |
551 | any addend that is used. ABFD, SECTION and ADDRESS identify the | |
252b5132 RH |
552 | location at which the overflow occurs; if this is the result of a |
553 | bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then | |
554 | ABFD will be NULL. */ | |
b34976b6 | 555 | bfd_boolean (*reloc_overflow) |
dfeffb9f L |
556 | (struct bfd_link_info *, struct bfd_link_hash_entry *entry, |
557 | const char *name, const char *reloc_name, bfd_vma addend, | |
558 | bfd *abfd, asection *section, bfd_vma address); | |
252b5132 | 559 | /* A function which is called when a dangerous reloc is performed. |
c17ae8a2 | 560 | MESSAGE is an appropriate message. |
252b5132 RH |
561 | ABFD, SECTION and ADDRESS identify the location at which the |
562 | problem occurred; if this is the result of a | |
563 | bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then | |
564 | ABFD will be NULL. */ | |
b34976b6 | 565 | bfd_boolean (*reloc_dangerous) |
8cf3f354 AM |
566 | (struct bfd_link_info *, const char *message, |
567 | bfd *abfd, asection *section, bfd_vma address); | |
252b5132 RH |
568 | /* A function which is called when a reloc is found to be attached |
569 | to a symbol which is not being written out. NAME is the name of | |
570 | the symbol. ABFD, SECTION and ADDRESS identify the location of | |
571 | the reloc; if this is the result of a | |
572 | bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then | |
573 | ABFD will be NULL. */ | |
b34976b6 | 574 | bfd_boolean (*unattached_reloc) |
8cf3f354 AM |
575 | (struct bfd_link_info *, const char *name, |
576 | bfd *abfd, asection *section, bfd_vma address); | |
252b5132 | 577 | /* A function which is called when a symbol in notice_hash is |
35ed3f94 AM |
578 | defined or referenced. H is the symbol. ABFD, SECTION and |
579 | ADDRESS are the (new) value of the symbol. If SECTION is | |
16d96b5b AM |
580 | bfd_und_section, this is a reference. FLAGS are the symbol |
581 | BSF_* flags. STRING is the name of the symbol to indirect to if | |
582 | the sym is indirect, or the warning string if a warning sym. */ | |
b34976b6 | 583 | bfd_boolean (*notice) |
35ed3f94 | 584 | (struct bfd_link_info *, struct bfd_link_hash_entry *h, |
16d96b5b AM |
585 | bfd *abfd, asection *section, bfd_vma address, flagword flags, |
586 | const char *string); | |
49fa1e15 | 587 | /* Error or warning link info message. */ |
e1fffbe6 AM |
588 | void (*einfo) |
589 | (const char *fmt, ...); | |
49fa1e15 AM |
590 | /* General link info message. */ |
591 | void (*info) | |
592 | (const char *fmt, ...); | |
593 | /* Message to be printed in linker map file. */ | |
594 | void (*minfo) | |
595 | (const char *fmt, ...); | |
2889e75b NC |
596 | /* This callback provides a chance for users of the BFD library to |
597 | override its decision about whether to place two adjacent sections | |
598 | into the same segment. */ | |
599 | bfd_boolean (*override_segment_assignment) | |
600 | (struct bfd_link_info *, bfd * abfd, | |
601 | asection * current_section, asection * previous_section, | |
602 | bfd_boolean new_segment); | |
252b5132 RH |
603 | }; |
604 | \f | |
605 | /* The linker builds link_order structures which tell the code how to | |
606 | include input data in the output file. */ | |
607 | ||
608 | /* These are the types of link_order structures. */ | |
609 | ||
610 | enum bfd_link_order_type | |
611 | { | |
612 | bfd_undefined_link_order, /* Undefined. */ | |
613 | bfd_indirect_link_order, /* Built from a section. */ | |
252b5132 RH |
614 | bfd_data_link_order, /* Set to explicit data. */ |
615 | bfd_section_reloc_link_order, /* Relocate against a section. */ | |
616 | bfd_symbol_reloc_link_order /* Relocate against a symbol. */ | |
617 | }; | |
618 | ||
619 | /* This is the link_order structure itself. These form a chain | |
6ed89c00 | 620 | attached to the output section whose contents they are describing. */ |
252b5132 | 621 | |
b34976b6 | 622 | struct bfd_link_order |
252b5132 RH |
623 | { |
624 | /* Next link_order in chain. */ | |
625 | struct bfd_link_order *next; | |
626 | /* Type of link_order. */ | |
627 | enum bfd_link_order_type type; | |
628 | /* Offset within output section. */ | |
b34976b6 | 629 | bfd_vma offset; |
252b5132 RH |
630 | /* Size within output section. */ |
631 | bfd_size_type size; | |
632 | /* Type specific information. */ | |
b34976b6 | 633 | union |
252b5132 | 634 | { |
b34976b6 | 635 | struct |
252b5132 RH |
636 | { |
637 | /* Section to include. If this is used, then | |
638 | section->output_section must be the section the | |
639 | link_order is attached to, section->output_offset must | |
eea6121a | 640 | equal the link_order offset field, and section->size |
252b5132 RH |
641 | must equal the link_order size field. Maybe these |
642 | restrictions should be relaxed someday. */ | |
643 | asection *section; | |
644 | } indirect; | |
645 | struct | |
646 | { | |
9a1b9f82 AM |
647 | /* Size of contents, or zero when contents size == size |
648 | within output section. | |
649 | A non-zero value allows filling of the output section | |
650 | with an arbitrary repeated pattern. */ | |
651 | unsigned int size; | |
652 | /* Data to put into file. */ | |
252b5132 RH |
653 | bfd_byte *contents; |
654 | } data; | |
655 | struct | |
656 | { | |
657 | /* Description of reloc to generate. Used for | |
658 | bfd_section_reloc_link_order and | |
659 | bfd_symbol_reloc_link_order. */ | |
660 | struct bfd_link_order_reloc *p; | |
661 | } reloc; | |
662 | } u; | |
663 | }; | |
664 | ||
665 | /* A linker order of type bfd_section_reloc_link_order or | |
666 | bfd_symbol_reloc_link_order means to create a reloc against a | |
667 | section or symbol, respectively. This is used to implement -Ur to | |
668 | generate relocs for the constructor tables. The | |
669 | bfd_link_order_reloc structure describes the reloc that BFD should | |
670 | create. It is similar to a arelent, but I didn't use arelent | |
671 | because the linker does not know anything about most symbols, and | |
672 | any asymbol structure it creates will be partially meaningless. | |
673 | This information could logically be in the bfd_link_order struct, | |
674 | but I didn't want to waste the space since these types of relocs | |
675 | are relatively rare. */ | |
676 | ||
677 | struct bfd_link_order_reloc | |
678 | { | |
679 | /* Reloc type. */ | |
680 | bfd_reloc_code_real_type reloc; | |
681 | ||
682 | union | |
683 | { | |
684 | /* For type bfd_section_reloc_link_order, this is the section | |
685 | the reloc should be against. This must be a section in the | |
686 | output BFD, not any of the input BFDs. */ | |
687 | asection *section; | |
688 | /* For type bfd_symbol_reloc_link_order, this is the name of the | |
689 | symbol the reloc should be against. */ | |
690 | const char *name; | |
691 | } u; | |
692 | ||
693 | /* Addend to use. The object file should contain zero. The BFD | |
694 | backend is responsible for filling in the contents of the object | |
695 | file correctly. For some object file formats (e.g., COFF) the | |
696 | addend must be stored into in the object file, and for some | |
697 | (e.g., SPARC a.out) it is kept in the reloc. */ | |
698 | bfd_vma addend; | |
699 | }; | |
700 | ||
701 | /* Allocate a new link_order for a section. */ | |
8cf3f354 | 702 | extern struct bfd_link_order *bfd_new_link_order (bfd *, asection *); |
252b5132 RH |
703 | |
704 | /* These structures are used to describe version information for the | |
705 | ELF linker. These structures could be manipulated entirely inside | |
706 | BFD, but it would be a pain. Instead, the regular linker sets up | |
707 | these structures, and then passes them into BFD. */ | |
708 | ||
108ba305 | 709 | /* Glob pattern for a version. */ |
252b5132 RH |
710 | |
711 | struct bfd_elf_version_expr | |
712 | { | |
108ba305 | 713 | /* Next glob pattern for this version. */ |
252b5132 | 714 | struct bfd_elf_version_expr *next; |
108ba305 | 715 | /* Glob pattern. */ |
252b5132 | 716 | const char *pattern; |
ae5a3597 AM |
717 | /* Set if pattern is not a glob. */ |
718 | unsigned int literal : 1; | |
31941635 | 719 | /* Defined by ".symver". */ |
108ba305 | 720 | unsigned int symver : 1; |
31941635 L |
721 | /* Defined by version script. */ |
722 | unsigned int script : 1; | |
108ba305 JJ |
723 | /* Pattern type. */ |
724 | #define BFD_ELF_VERSION_C_TYPE 1 | |
725 | #define BFD_ELF_VERSION_CXX_TYPE 2 | |
726 | #define BFD_ELF_VERSION_JAVA_TYPE 4 | |
727 | unsigned int mask : 3; | |
728 | }; | |
729 | ||
730 | struct bfd_elf_version_expr_head | |
731 | { | |
732 | /* List of all patterns, both wildcards and non-wildcards. */ | |
733 | struct bfd_elf_version_expr *list; | |
734 | /* Hash table for non-wildcards. */ | |
735 | void *htab; | |
736 | /* Remaining patterns. */ | |
737 | struct bfd_elf_version_expr *remaining; | |
738 | /* What kind of pattern types are present in list (bitmask). */ | |
739 | unsigned int mask; | |
252b5132 RH |
740 | }; |
741 | ||
742 | /* Version dependencies. */ | |
743 | ||
744 | struct bfd_elf_version_deps | |
745 | { | |
746 | /* Next dependency for this version. */ | |
747 | struct bfd_elf_version_deps *next; | |
748 | /* The version which this version depends upon. */ | |
749 | struct bfd_elf_version_tree *version_needed; | |
750 | }; | |
751 | ||
752 | /* A node in the version tree. */ | |
753 | ||
754 | struct bfd_elf_version_tree | |
755 | { | |
756 | /* Next version. */ | |
757 | struct bfd_elf_version_tree *next; | |
758 | /* Name of this version. */ | |
759 | const char *name; | |
760 | /* Version number. */ | |
761 | unsigned int vernum; | |
762 | /* Regular expressions for global symbols in this version. */ | |
108ba305 | 763 | struct bfd_elf_version_expr_head globals; |
252b5132 | 764 | /* Regular expressions for local symbols in this version. */ |
108ba305 | 765 | struct bfd_elf_version_expr_head locals; |
252b5132 RH |
766 | /* List of versions which this version depends upon. */ |
767 | struct bfd_elf_version_deps *deps; | |
768 | /* Index of the version name. This is used within BFD. */ | |
769 | unsigned int name_indx; | |
770 | /* Whether this version tree was used. This is used within BFD. */ | |
771 | int used; | |
108ba305 JJ |
772 | /* Matching hook. */ |
773 | struct bfd_elf_version_expr *(*match) | |
774 | (struct bfd_elf_version_expr_head *head, | |
775 | struct bfd_elf_version_expr *prev, const char *sym); | |
252b5132 RH |
776 | }; |
777 | ||
55255dae L |
778 | struct bfd_elf_dynamic_list |
779 | { | |
780 | struct bfd_elf_version_expr_head head; | |
781 | struct bfd_elf_version_expr *(*match) | |
782 | (struct bfd_elf_version_expr_head *head, | |
783 | struct bfd_elf_version_expr *prev, const char *sym); | |
784 | }; | |
785 | ||
252b5132 | 786 | #endif |