* coffswap.h (coff_swap_aux_in): add semicolon to make MSVC happy.
[deliverable/binutils-gdb.git] / bfd / elflink.h
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20 /* ELF linker code. */
21
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
24
25 struct elf_info_failed
26 {
27 boolean failed;
28 struct bfd_link_info *info;
29 };
30
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_link_renumber_dynsyms
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53
54 /* Given an ELF BFD, add symbols to the global hash table as
55 appropriate. */
56
57 boolean
58 elf_bfd_link_add_symbols (abfd, info)
59 bfd *abfd;
60 struct bfd_link_info *info;
61 {
62 switch (bfd_get_format (abfd))
63 {
64 case bfd_object:
65 return elf_link_add_object_symbols (abfd, info);
66 case bfd_archive:
67 return elf_link_add_archive_symbols (abfd, info);
68 default:
69 bfd_set_error (bfd_error_wrong_format);
70 return false;
71 }
72 }
73 \f
74
75 /* Add symbols from an ELF archive file to the linker hash table. We
76 don't use _bfd_generic_link_add_archive_symbols because of a
77 problem which arises on UnixWare. The UnixWare libc.so is an
78 archive which includes an entry libc.so.1 which defines a bunch of
79 symbols. The libc.so archive also includes a number of other
80 object files, which also define symbols, some of which are the same
81 as those defined in libc.so.1. Correct linking requires that we
82 consider each object file in turn, and include it if it defines any
83 symbols we need. _bfd_generic_link_add_archive_symbols does not do
84 this; it looks through the list of undefined symbols, and includes
85 any object file which defines them. When this algorithm is used on
86 UnixWare, it winds up pulling in libc.so.1 early and defining a
87 bunch of symbols. This means that some of the other objects in the
88 archive are not included in the link, which is incorrect since they
89 precede libc.so.1 in the archive.
90
91 Fortunately, ELF archive handling is simpler than that done by
92 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
93 oddities. In ELF, if we find a symbol in the archive map, and the
94 symbol is currently undefined, we know that we must pull in that
95 object file.
96
97 Unfortunately, we do have to make multiple passes over the symbol
98 table until nothing further is resolved. */
99
100 static boolean
101 elf_link_add_archive_symbols (abfd, info)
102 bfd *abfd;
103 struct bfd_link_info *info;
104 {
105 symindex c;
106 boolean *defined = NULL;
107 boolean *included = NULL;
108 carsym *symdefs;
109 boolean loop;
110
111 if (! bfd_has_map (abfd))
112 {
113 /* An empty archive is a special case. */
114 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
115 return true;
116 bfd_set_error (bfd_error_no_armap);
117 return false;
118 }
119
120 /* Keep track of all symbols we know to be already defined, and all
121 files we know to be already included. This is to speed up the
122 second and subsequent passes. */
123 c = bfd_ardata (abfd)->symdef_count;
124 if (c == 0)
125 return true;
126 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
127 included = (boolean *) bfd_malloc (c * sizeof (boolean));
128 if (defined == (boolean *) NULL || included == (boolean *) NULL)
129 goto error_return;
130 memset (defined, 0, c * sizeof (boolean));
131 memset (included, 0, c * sizeof (boolean));
132
133 symdefs = bfd_ardata (abfd)->symdefs;
134
135 do
136 {
137 file_ptr last;
138 symindex i;
139 carsym *symdef;
140 carsym *symdefend;
141
142 loop = false;
143 last = -1;
144
145 symdef = symdefs;
146 symdefend = symdef + c;
147 for (i = 0; symdef < symdefend; symdef++, i++)
148 {
149 struct elf_link_hash_entry *h;
150 bfd *element;
151 struct bfd_link_hash_entry *undefs_tail;
152 symindex mark;
153
154 if (defined[i] || included[i])
155 continue;
156 if (symdef->file_offset == last)
157 {
158 included[i] = true;
159 continue;
160 }
161
162 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
163 false, false, false);
164
165 if (h == NULL)
166 {
167 char *p, *copy;
168
169 /* If this is a default version (the name contains @@),
170 look up the symbol again without the version. The
171 effect is that references to the symbol without the
172 version will be matched by the default symbol in the
173 archive. */
174
175 p = strchr (symdef->name, ELF_VER_CHR);
176 if (p == NULL || p[1] != ELF_VER_CHR)
177 continue;
178
179 copy = bfd_alloc (abfd, p - symdef->name + 1);
180 if (copy == NULL)
181 goto error_return;
182 memcpy (copy, symdef->name, p - symdef->name);
183 copy[p - symdef->name] = '\0';
184
185 h = elf_link_hash_lookup (elf_hash_table (info), copy,
186 false, false, false);
187
188 bfd_release (abfd, copy);
189 }
190
191 if (h == NULL)
192 continue;
193
194 if (h->root.type != bfd_link_hash_undefined)
195 {
196 if (h->root.type != bfd_link_hash_undefweak)
197 defined[i] = true;
198 continue;
199 }
200
201 /* We need to include this archive member. */
202
203 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
204 if (element == (bfd *) NULL)
205 goto error_return;
206
207 if (! bfd_check_format (element, bfd_object))
208 goto error_return;
209
210 /* Doublecheck that we have not included this object
211 already--it should be impossible, but there may be
212 something wrong with the archive. */
213 if (element->archive_pass != 0)
214 {
215 bfd_set_error (bfd_error_bad_value);
216 goto error_return;
217 }
218 element->archive_pass = 1;
219
220 undefs_tail = info->hash->undefs_tail;
221
222 if (! (*info->callbacks->add_archive_element) (info, element,
223 symdef->name))
224 goto error_return;
225 if (! elf_link_add_object_symbols (element, info))
226 goto error_return;
227
228 /* If there are any new undefined symbols, we need to make
229 another pass through the archive in order to see whether
230 they can be defined. FIXME: This isn't perfect, because
231 common symbols wind up on undefs_tail and because an
232 undefined symbol which is defined later on in this pass
233 does not require another pass. This isn't a bug, but it
234 does make the code less efficient than it could be. */
235 if (undefs_tail != info->hash->undefs_tail)
236 loop = true;
237
238 /* Look backward to mark all symbols from this object file
239 which we have already seen in this pass. */
240 mark = i;
241 do
242 {
243 included[mark] = true;
244 if (mark == 0)
245 break;
246 --mark;
247 }
248 while (symdefs[mark].file_offset == symdef->file_offset);
249
250 /* We mark subsequent symbols from this object file as we go
251 on through the loop. */
252 last = symdef->file_offset;
253 }
254 }
255 while (loop);
256
257 free (defined);
258 free (included);
259
260 return true;
261
262 error_return:
263 if (defined != (boolean *) NULL)
264 free (defined);
265 if (included != (boolean *) NULL)
266 free (included);
267 return false;
268 }
269
270 /* This function is called when we want to define a new symbol. It
271 handles the various cases which arise when we find a definition in
272 a dynamic object, or when there is already a definition in a
273 dynamic object. The new symbol is described by NAME, SYM, PSEC,
274 and PVALUE. We set SYM_HASH to the hash table entry. We set
275 OVERRIDE if the old symbol is overriding a new definition. We set
276 TYPE_CHANGE_OK if it is OK for the type to change. We set
277 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
278 change, we mean that we shouldn't warn if the type or size does
279 change. */
280
281 static boolean
282 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
283 override, type_change_ok, size_change_ok)
284 bfd *abfd;
285 struct bfd_link_info *info;
286 const char *name;
287 Elf_Internal_Sym *sym;
288 asection **psec;
289 bfd_vma *pvalue;
290 struct elf_link_hash_entry **sym_hash;
291 boolean *override;
292 boolean *type_change_ok;
293 boolean *size_change_ok;
294 {
295 asection *sec;
296 struct elf_link_hash_entry *h;
297 int bind;
298 bfd *oldbfd;
299 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
300
301 /* This code is for coping with dynamic objects, and is only useful
302 if we are doing an ELF link. */
303 if (info->hash->creator != abfd->xvec)
304 return true;
305
306 *override = false;
307 *type_change_ok = false;
308 *size_change_ok = false;
309
310 sec = *psec;
311 bind = ELF_ST_BIND (sym->st_info);
312
313 if (! bfd_is_und_section (sec))
314 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
315 else
316 h = ((struct elf_link_hash_entry *)
317 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
318 if (h == NULL)
319 return false;
320 *sym_hash = h;
321
322 /* For merging, we only care about real symbols. */
323
324 while (h->root.type == bfd_link_hash_indirect
325 || h->root.type == bfd_link_hash_warning)
326 h = (struct elf_link_hash_entry *) h->root.u.i.link;
327
328 /* If we just created the symbol, mark it as being an ELF symbol.
329 Other than that, there is nothing to do--there is no merge issue
330 with a newly defined symbol--so we just return. */
331
332 if (h->root.type == bfd_link_hash_new)
333 {
334 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
335 return true;
336 }
337
338 /* OLDBFD is a BFD associated with the existing symbol. */
339
340 switch (h->root.type)
341 {
342 default:
343 oldbfd = NULL;
344 break;
345
346 case bfd_link_hash_undefined:
347 case bfd_link_hash_undefweak:
348 oldbfd = h->root.u.undef.abfd;
349 break;
350
351 case bfd_link_hash_defined:
352 case bfd_link_hash_defweak:
353 oldbfd = h->root.u.def.section->owner;
354 break;
355
356 case bfd_link_hash_common:
357 oldbfd = h->root.u.c.p->section->owner;
358 break;
359 }
360
361 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
362 respectively, is from a dynamic object. */
363
364 if ((abfd->flags & DYNAMIC) != 0)
365 newdyn = true;
366 else
367 newdyn = false;
368
369 if (oldbfd == NULL || (oldbfd->flags & DYNAMIC) == 0)
370 olddyn = false;
371 else
372 olddyn = true;
373
374 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
375 respectively, appear to be a definition rather than reference. */
376
377 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
378 newdef = false;
379 else
380 newdef = true;
381
382 if (h->root.type == bfd_link_hash_undefined
383 || h->root.type == bfd_link_hash_undefweak
384 || h->root.type == bfd_link_hash_common)
385 olddef = false;
386 else
387 olddef = true;
388
389 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
390 symbol, respectively, appears to be a common symbol in a dynamic
391 object. If a symbol appears in an uninitialized section, and is
392 not weak, and is not a function, then it may be a common symbol
393 which was resolved when the dynamic object was created. We want
394 to treat such symbols specially, because they raise special
395 considerations when setting the symbol size: if the symbol
396 appears as a common symbol in a regular object, and the size in
397 the regular object is larger, we must make sure that we use the
398 larger size. This problematic case can always be avoided in C,
399 but it must be handled correctly when using Fortran shared
400 libraries.
401
402 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
403 likewise for OLDDYNCOMMON and OLDDEF.
404
405 Note that this test is just a heuristic, and that it is quite
406 possible to have an uninitialized symbol in a shared object which
407 is really a definition, rather than a common symbol. This could
408 lead to some minor confusion when the symbol really is a common
409 symbol in some regular object. However, I think it will be
410 harmless. */
411
412 if (newdyn
413 && newdef
414 && (sec->flags & SEC_ALLOC) != 0
415 && (sec->flags & SEC_LOAD) == 0
416 && sym->st_size > 0
417 && bind != STB_WEAK
418 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
419 newdyncommon = true;
420 else
421 newdyncommon = false;
422
423 if (olddyn
424 && olddef
425 && h->root.type == bfd_link_hash_defined
426 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
427 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
428 && (h->root.u.def.section->flags & SEC_LOAD) == 0
429 && h->size > 0
430 && h->type != STT_FUNC)
431 olddyncommon = true;
432 else
433 olddyncommon = false;
434
435 /* It's OK to change the type if either the existing symbol or the
436 new symbol is weak. */
437
438 if (h->root.type == bfd_link_hash_defweak
439 || h->root.type == bfd_link_hash_undefweak
440 || bind == STB_WEAK)
441 *type_change_ok = true;
442
443 /* It's OK to change the size if either the existing symbol or the
444 new symbol is weak, or if the old symbol is undefined. */
445
446 if (*type_change_ok
447 || h->root.type == bfd_link_hash_undefined)
448 *size_change_ok = true;
449
450 /* If both the old and the new symbols look like common symbols in a
451 dynamic object, set the size of the symbol to the larger of the
452 two. */
453
454 if (olddyncommon
455 && newdyncommon
456 && sym->st_size != h->size)
457 {
458 /* Since we think we have two common symbols, issue a multiple
459 common warning if desired. Note that we only warn if the
460 size is different. If the size is the same, we simply let
461 the old symbol override the new one as normally happens with
462 symbols defined in dynamic objects. */
463
464 if (! ((*info->callbacks->multiple_common)
465 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
466 h->size, abfd, bfd_link_hash_common, sym->st_size)))
467 return false;
468
469 if (sym->st_size > h->size)
470 h->size = sym->st_size;
471
472 *size_change_ok = true;
473 }
474
475 /* If we are looking at a dynamic object, and we have found a
476 definition, we need to see if the symbol was already defined by
477 some other object. If so, we want to use the existing
478 definition, and we do not want to report a multiple symbol
479 definition error; we do this by clobbering *PSEC to be
480 bfd_und_section_ptr.
481
482 We treat a common symbol as a definition if the symbol in the
483 shared library is a function, since common symbols always
484 represent variables; this can cause confusion in principle, but
485 any such confusion would seem to indicate an erroneous program or
486 shared library. We also permit a common symbol in a regular
487 object to override a weak symbol in a shared object. */
488
489 if (newdyn
490 && newdef
491 && (olddef
492 || (h->root.type == bfd_link_hash_common
493 && (bind == STB_WEAK
494 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
495 {
496 *override = true;
497 newdef = false;
498 newdyncommon = false;
499
500 *psec = sec = bfd_und_section_ptr;
501 *size_change_ok = true;
502
503 /* If we get here when the old symbol is a common symbol, then
504 we are explicitly letting it override a weak symbol or
505 function in a dynamic object, and we don't want to warn about
506 a type change. If the old symbol is a defined symbol, a type
507 change warning may still be appropriate. */
508
509 if (h->root.type == bfd_link_hash_common)
510 *type_change_ok = true;
511 }
512
513 /* Handle the special case of an old common symbol merging with a
514 new symbol which looks like a common symbol in a shared object.
515 We change *PSEC and *PVALUE to make the new symbol look like a
516 common symbol, and let _bfd_generic_link_add_one_symbol will do
517 the right thing. */
518
519 if (newdyncommon
520 && h->root.type == bfd_link_hash_common)
521 {
522 *override = true;
523 newdef = false;
524 newdyncommon = false;
525 *pvalue = sym->st_size;
526 *psec = sec = bfd_com_section_ptr;
527 *size_change_ok = true;
528 }
529
530 /* If the old symbol is from a dynamic object, and the new symbol is
531 a definition which is not from a dynamic object, then the new
532 symbol overrides the old symbol. Symbols from regular files
533 always take precedence over symbols from dynamic objects, even if
534 they are defined after the dynamic object in the link.
535
536 As above, we again permit a common symbol in a regular object to
537 override a definition in a shared object if the shared object
538 symbol is a function or is weak. */
539
540 if (! newdyn
541 && (newdef
542 || (bfd_is_com_section (sec)
543 && (h->root.type == bfd_link_hash_defweak
544 || h->type == STT_FUNC)))
545 && olddyn
546 && olddef
547 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
548 {
549 /* Change the hash table entry to undefined, and let
550 _bfd_generic_link_add_one_symbol do the right thing with the
551 new definition. */
552
553 h->root.type = bfd_link_hash_undefined;
554 h->root.u.undef.abfd = h->root.u.def.section->owner;
555 *size_change_ok = true;
556
557 olddef = false;
558 olddyncommon = false;
559
560 /* We again permit a type change when a common symbol may be
561 overriding a function. */
562
563 if (bfd_is_com_section (sec))
564 *type_change_ok = true;
565
566 /* This union may have been set to be non-NULL when this symbol
567 was seen in a dynamic object. We must force the union to be
568 NULL, so that it is correct for a regular symbol. */
569
570 h->verinfo.vertree = NULL;
571
572 /* In this special case, if H is the target of an indirection,
573 we want the caller to frob with H rather than with the
574 indirect symbol. That will permit the caller to redefine the
575 target of the indirection, rather than the indirect symbol
576 itself. FIXME: This will break the -y option if we store a
577 symbol with a different name. */
578 *sym_hash = h;
579 }
580
581 /* Handle the special case of a new common symbol merging with an
582 old symbol that looks like it might be a common symbol defined in
583 a shared object. Note that we have already handled the case in
584 which a new common symbol should simply override the definition
585 in the shared library. */
586
587 if (! newdyn
588 && bfd_is_com_section (sec)
589 && olddyncommon)
590 {
591 /* It would be best if we could set the hash table entry to a
592 common symbol, but we don't know what to use for the section
593 or the alignment. */
594 if (! ((*info->callbacks->multiple_common)
595 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
596 h->size, abfd, bfd_link_hash_common, sym->st_size)))
597 return false;
598
599 /* If the predumed common symbol in the dynamic object is
600 larger, pretend that the new symbol has its size. */
601
602 if (h->size > *pvalue)
603 *pvalue = h->size;
604
605 /* FIXME: We no longer know the alignment required by the symbol
606 in the dynamic object, so we just wind up using the one from
607 the regular object. */
608
609 olddef = false;
610 olddyncommon = false;
611
612 h->root.type = bfd_link_hash_undefined;
613 h->root.u.undef.abfd = h->root.u.def.section->owner;
614
615 *size_change_ok = true;
616 *type_change_ok = true;
617
618 h->verinfo.vertree = NULL;
619 }
620
621 return true;
622 }
623
624 /* Add symbols from an ELF object file to the linker hash table. */
625
626 static boolean
627 elf_link_add_object_symbols (abfd, info)
628 bfd *abfd;
629 struct bfd_link_info *info;
630 {
631 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
632 const Elf_Internal_Sym *,
633 const char **, flagword *,
634 asection **, bfd_vma *));
635 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
636 asection *, const Elf_Internal_Rela *));
637 boolean collect;
638 Elf_Internal_Shdr *hdr;
639 size_t symcount;
640 size_t extsymcount;
641 size_t extsymoff;
642 Elf_External_Sym *buf = NULL;
643 struct elf_link_hash_entry **sym_hash;
644 boolean dynamic;
645 bfd_byte *dynver = NULL;
646 Elf_External_Versym *extversym = NULL;
647 Elf_External_Versym *ever;
648 Elf_External_Dyn *dynbuf = NULL;
649 struct elf_link_hash_entry *weaks;
650 Elf_External_Sym *esym;
651 Elf_External_Sym *esymend;
652
653 add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook;
654 collect = get_elf_backend_data (abfd)->collect;
655
656 if ((abfd->flags & DYNAMIC) == 0)
657 dynamic = false;
658 else
659 {
660 dynamic = true;
661
662 /* You can't use -r against a dynamic object. Also, there's no
663 hope of using a dynamic object which does not exactly match
664 the format of the output file. */
665 if (info->relocateable || info->hash->creator != abfd->xvec)
666 {
667 bfd_set_error (bfd_error_invalid_operation);
668 goto error_return;
669 }
670 }
671
672 /* As a GNU extension, any input sections which are named
673 .gnu.warning.SYMBOL are treated as warning symbols for the given
674 symbol. This differs from .gnu.warning sections, which generate
675 warnings when they are included in an output file. */
676 if (! info->shared)
677 {
678 asection *s;
679
680 for (s = abfd->sections; s != NULL; s = s->next)
681 {
682 const char *name;
683
684 name = bfd_get_section_name (abfd, s);
685 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
686 {
687 char *msg;
688 bfd_size_type sz;
689
690 name += sizeof ".gnu.warning." - 1;
691
692 /* If this is a shared object, then look up the symbol
693 in the hash table. If it is there, and it is already
694 been defined, then we will not be using the entry
695 from this shared object, so we don't need to warn.
696 FIXME: If we see the definition in a regular object
697 later on, we will warn, but we shouldn't. The only
698 fix is to keep track of what warnings we are supposed
699 to emit, and then handle them all at the end of the
700 link. */
701 if (dynamic && abfd->xvec == info->hash->creator)
702 {
703 struct elf_link_hash_entry *h;
704
705 h = elf_link_hash_lookup (elf_hash_table (info), name,
706 false, false, true);
707
708 /* FIXME: What about bfd_link_hash_common? */
709 if (h != NULL
710 && (h->root.type == bfd_link_hash_defined
711 || h->root.type == bfd_link_hash_defweak))
712 {
713 /* We don't want to issue this warning. Clobber
714 the section size so that the warning does not
715 get copied into the output file. */
716 s->_raw_size = 0;
717 continue;
718 }
719 }
720
721 sz = bfd_section_size (abfd, s);
722 msg = (char *) bfd_alloc (abfd, sz);
723 if (msg == NULL)
724 goto error_return;
725
726 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
727 goto error_return;
728
729 if (! (_bfd_generic_link_add_one_symbol
730 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
731 false, collect, (struct bfd_link_hash_entry **) NULL)))
732 goto error_return;
733
734 if (! info->relocateable)
735 {
736 /* Clobber the section size so that the warning does
737 not get copied into the output file. */
738 s->_raw_size = 0;
739 }
740 }
741 }
742 }
743
744 /* If this is a dynamic object, we always link against the .dynsym
745 symbol table, not the .symtab symbol table. The dynamic linker
746 will only see the .dynsym symbol table, so there is no reason to
747 look at .symtab for a dynamic object. */
748
749 if (! dynamic || elf_dynsymtab (abfd) == 0)
750 hdr = &elf_tdata (abfd)->symtab_hdr;
751 else
752 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
753
754 if (dynamic)
755 {
756 /* Read in any version definitions. */
757
758 if (! _bfd_elf_slurp_version_tables (abfd))
759 goto error_return;
760
761 /* Read in the symbol versions, but don't bother to convert them
762 to internal format. */
763 if (elf_dynversym (abfd) != 0)
764 {
765 Elf_Internal_Shdr *versymhdr;
766
767 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
768 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
769 if (extversym == NULL)
770 goto error_return;
771 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
772 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
773 != versymhdr->sh_size))
774 goto error_return;
775 }
776 }
777
778 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
779
780 /* The sh_info field of the symtab header tells us where the
781 external symbols start. We don't care about the local symbols at
782 this point. */
783 if (elf_bad_symtab (abfd))
784 {
785 extsymcount = symcount;
786 extsymoff = 0;
787 }
788 else
789 {
790 extsymcount = symcount - hdr->sh_info;
791 extsymoff = hdr->sh_info;
792 }
793
794 buf = ((Elf_External_Sym *)
795 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
796 if (buf == NULL && extsymcount != 0)
797 goto error_return;
798
799 /* We store a pointer to the hash table entry for each external
800 symbol. */
801 sym_hash = ((struct elf_link_hash_entry **)
802 bfd_alloc (abfd,
803 extsymcount * sizeof (struct elf_link_hash_entry *)));
804 if (sym_hash == NULL)
805 goto error_return;
806 elf_sym_hashes (abfd) = sym_hash;
807
808 if (! dynamic)
809 {
810 /* If we are creating a shared library, create all the dynamic
811 sections immediately. We need to attach them to something,
812 so we attach them to this BFD, provided it is the right
813 format. FIXME: If there are no input BFD's of the same
814 format as the output, we can't make a shared library. */
815 if (info->shared
816 && ! elf_hash_table (info)->dynamic_sections_created
817 && abfd->xvec == info->hash->creator)
818 {
819 if (! elf_link_create_dynamic_sections (abfd, info))
820 goto error_return;
821 }
822 }
823 else
824 {
825 asection *s;
826 boolean add_needed;
827 const char *name;
828 bfd_size_type oldsize;
829 bfd_size_type strindex;
830
831 /* Find the name to use in a DT_NEEDED entry that refers to this
832 object. If the object has a DT_SONAME entry, we use it.
833 Otherwise, if the generic linker stuck something in
834 elf_dt_name, we use that. Otherwise, we just use the file
835 name. If the generic linker put a null string into
836 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
837 there is a DT_SONAME entry. */
838 add_needed = true;
839 name = bfd_get_filename (abfd);
840 if (elf_dt_name (abfd) != NULL)
841 {
842 name = elf_dt_name (abfd);
843 if (*name == '\0')
844 add_needed = false;
845 }
846 s = bfd_get_section_by_name (abfd, ".dynamic");
847 if (s != NULL)
848 {
849 Elf_External_Dyn *extdyn;
850 Elf_External_Dyn *extdynend;
851 int elfsec;
852 unsigned long link;
853
854 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
855 if (dynbuf == NULL)
856 goto error_return;
857
858 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
859 (file_ptr) 0, s->_raw_size))
860 goto error_return;
861
862 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
863 if (elfsec == -1)
864 goto error_return;
865 link = elf_elfsections (abfd)[elfsec]->sh_link;
866
867 extdyn = dynbuf;
868 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
869 for (; extdyn < extdynend; extdyn++)
870 {
871 Elf_Internal_Dyn dyn;
872
873 elf_swap_dyn_in (abfd, extdyn, &dyn);
874 if (dyn.d_tag == DT_SONAME)
875 {
876 name = bfd_elf_string_from_elf_section (abfd, link,
877 dyn.d_un.d_val);
878 if (name == NULL)
879 goto error_return;
880 }
881 if (dyn.d_tag == DT_NEEDED)
882 {
883 struct bfd_link_needed_list *n, **pn;
884 char *fnm, *anm;
885
886 n = ((struct bfd_link_needed_list *)
887 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
888 fnm = bfd_elf_string_from_elf_section (abfd, link,
889 dyn.d_un.d_val);
890 if (n == NULL || fnm == NULL)
891 goto error_return;
892 anm = bfd_alloc (abfd, strlen (fnm) + 1);
893 if (anm == NULL)
894 goto error_return;
895 strcpy (anm, fnm);
896 n->name = anm;
897 n->by = abfd;
898 n->next = NULL;
899 for (pn = &elf_hash_table (info)->needed;
900 *pn != NULL;
901 pn = &(*pn)->next)
902 ;
903 *pn = n;
904 }
905 }
906
907 free (dynbuf);
908 dynbuf = NULL;
909 }
910
911 /* We do not want to include any of the sections in a dynamic
912 object in the output file. We hack by simply clobbering the
913 list of sections in the BFD. This could be handled more
914 cleanly by, say, a new section flag; the existing
915 SEC_NEVER_LOAD flag is not the one we want, because that one
916 still implies that the section takes up space in the output
917 file. */
918 abfd->sections = NULL;
919 abfd->section_count = 0;
920
921 /* If this is the first dynamic object found in the link, create
922 the special sections required for dynamic linking. */
923 if (! elf_hash_table (info)->dynamic_sections_created)
924 {
925 if (! elf_link_create_dynamic_sections (abfd, info))
926 goto error_return;
927 }
928
929 if (add_needed)
930 {
931 /* Add a DT_NEEDED entry for this dynamic object. */
932 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
933 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
934 true, false);
935 if (strindex == (bfd_size_type) -1)
936 goto error_return;
937
938 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
939 {
940 asection *sdyn;
941 Elf_External_Dyn *dyncon, *dynconend;
942
943 /* The hash table size did not change, which means that
944 the dynamic object name was already entered. If we
945 have already included this dynamic object in the
946 link, just ignore it. There is no reason to include
947 a particular dynamic object more than once. */
948 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
949 ".dynamic");
950 BFD_ASSERT (sdyn != NULL);
951
952 dyncon = (Elf_External_Dyn *) sdyn->contents;
953 dynconend = (Elf_External_Dyn *) (sdyn->contents +
954 sdyn->_raw_size);
955 for (; dyncon < dynconend; dyncon++)
956 {
957 Elf_Internal_Dyn dyn;
958
959 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
960 &dyn);
961 if (dyn.d_tag == DT_NEEDED
962 && dyn.d_un.d_val == strindex)
963 {
964 if (buf != NULL)
965 free (buf);
966 if (extversym != NULL)
967 free (extversym);
968 return true;
969 }
970 }
971 }
972
973 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
974 goto error_return;
975 }
976
977 /* Save the SONAME, if there is one, because sometimes the
978 linker emulation code will need to know it. */
979 if (*name == '\0')
980 name = bfd_get_filename (abfd);
981 elf_dt_name (abfd) = name;
982 }
983
984 if (bfd_seek (abfd,
985 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
986 SEEK_SET) != 0
987 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
988 != extsymcount * sizeof (Elf_External_Sym)))
989 goto error_return;
990
991 weaks = NULL;
992
993 ever = extversym != NULL ? extversym + extsymoff : NULL;
994 esymend = buf + extsymcount;
995 for (esym = buf;
996 esym < esymend;
997 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
998 {
999 Elf_Internal_Sym sym;
1000 int bind;
1001 bfd_vma value;
1002 asection *sec;
1003 flagword flags;
1004 const char *name;
1005 struct elf_link_hash_entry *h;
1006 boolean definition;
1007 boolean size_change_ok, type_change_ok;
1008 boolean new_weakdef;
1009 unsigned int old_alignment;
1010
1011 elf_swap_symbol_in (abfd, esym, &sym);
1012
1013 flags = BSF_NO_FLAGS;
1014 sec = NULL;
1015 value = sym.st_value;
1016 *sym_hash = NULL;
1017
1018 bind = ELF_ST_BIND (sym.st_info);
1019 if (bind == STB_LOCAL)
1020 {
1021 /* This should be impossible, since ELF requires that all
1022 global symbols follow all local symbols, and that sh_info
1023 point to the first global symbol. Unfortunatealy, Irix 5
1024 screws this up. */
1025 continue;
1026 }
1027 else if (bind == STB_GLOBAL)
1028 {
1029 if (sym.st_shndx != SHN_UNDEF
1030 && sym.st_shndx != SHN_COMMON)
1031 flags = BSF_GLOBAL;
1032 else
1033 flags = 0;
1034 }
1035 else if (bind == STB_WEAK)
1036 flags = BSF_WEAK;
1037 else
1038 {
1039 /* Leave it up to the processor backend. */
1040 }
1041
1042 if (sym.st_shndx == SHN_UNDEF)
1043 sec = bfd_und_section_ptr;
1044 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1045 {
1046 sec = section_from_elf_index (abfd, sym.st_shndx);
1047 if (sec == NULL)
1048 sec = bfd_abs_section_ptr;
1049 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1050 value -= sec->vma;
1051 }
1052 else if (sym.st_shndx == SHN_ABS)
1053 sec = bfd_abs_section_ptr;
1054 else if (sym.st_shndx == SHN_COMMON)
1055 {
1056 sec = bfd_com_section_ptr;
1057 /* What ELF calls the size we call the value. What ELF
1058 calls the value we call the alignment. */
1059 value = sym.st_size;
1060 }
1061 else
1062 {
1063 /* Leave it up to the processor backend. */
1064 }
1065
1066 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1067 if (name == (const char *) NULL)
1068 goto error_return;
1069
1070 if (add_symbol_hook)
1071 {
1072 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1073 &value))
1074 goto error_return;
1075
1076 /* The hook function sets the name to NULL if this symbol
1077 should be skipped for some reason. */
1078 if (name == (const char *) NULL)
1079 continue;
1080 }
1081
1082 /* Sanity check that all possibilities were handled. */
1083 if (sec == (asection *) NULL)
1084 {
1085 bfd_set_error (bfd_error_bad_value);
1086 goto error_return;
1087 }
1088
1089 if (bfd_is_und_section (sec)
1090 || bfd_is_com_section (sec))
1091 definition = false;
1092 else
1093 definition = true;
1094
1095 size_change_ok = false;
1096 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1097 old_alignment = 0;
1098 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1099 {
1100 Elf_Internal_Versym iver;
1101 int vernum;
1102 boolean override;
1103
1104 if (ever != NULL)
1105 {
1106 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1107 vernum = iver.vs_vers & VERSYM_VERSION;
1108
1109 /* If this is a hidden symbol, or if it is not version
1110 1, we append the version name to the symbol name.
1111 However, we do not modify a non-hidden absolute
1112 symbol, because it might be the version symbol
1113 itself. FIXME: What if it isn't? */
1114 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1115 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1116 {
1117 const char *verstr;
1118 int namelen, newlen;
1119 char *newname, *p;
1120
1121 if (sym.st_shndx != SHN_UNDEF)
1122 {
1123 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1124 {
1125 (*_bfd_error_handler)
1126 ("%s: %s: invalid version %d (max %d)",
1127 abfd->filename, name, vernum,
1128 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1129 bfd_set_error (bfd_error_bad_value);
1130 goto error_return;
1131 }
1132 else if (vernum > 1)
1133 verstr =
1134 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1135 else
1136 verstr = "";
1137 }
1138 else
1139 {
1140 /* We cannot simply test for the number of
1141 entries in the VERNEED section since the
1142 numbers for the needed versions do not start
1143 at 0. */
1144 Elf_Internal_Verneed *t;
1145
1146 verstr = NULL;
1147 for (t = elf_tdata (abfd)->verref;
1148 t != NULL;
1149 t = t->vn_nextref)
1150 {
1151 Elf_Internal_Vernaux *a;
1152
1153 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1154 {
1155 if (a->vna_other == vernum)
1156 {
1157 verstr = a->vna_nodename;
1158 break;
1159 }
1160 }
1161 if (a != NULL)
1162 break;
1163 }
1164 if (verstr == NULL)
1165 {
1166 (*_bfd_error_handler)
1167 ("%s: %s: invalid needed version %d",
1168 abfd->filename, name, vernum);
1169 bfd_set_error (bfd_error_bad_value);
1170 goto error_return;
1171 }
1172 }
1173
1174 namelen = strlen (name);
1175 newlen = namelen + strlen (verstr) + 2;
1176 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1177 ++newlen;
1178
1179 newname = (char *) bfd_alloc (abfd, newlen);
1180 if (newname == NULL)
1181 goto error_return;
1182 strcpy (newname, name);
1183 p = newname + namelen;
1184 *p++ = ELF_VER_CHR;
1185 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1186 *p++ = ELF_VER_CHR;
1187 strcpy (p, verstr);
1188
1189 name = newname;
1190 }
1191 }
1192
1193 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1194 sym_hash, &override, &type_change_ok,
1195 &size_change_ok))
1196 goto error_return;
1197
1198 if (override)
1199 definition = false;
1200
1201 h = *sym_hash;
1202 while (h->root.type == bfd_link_hash_indirect
1203 || h->root.type == bfd_link_hash_warning)
1204 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1205
1206 /* Remember the old alignment if this is a common symbol, so
1207 that we don't reduce the alignment later on. We can't
1208 check later, because _bfd_generic_link_add_one_symbol
1209 will set a default for the alignment which we want to
1210 override. */
1211 if (h->root.type == bfd_link_hash_common)
1212 old_alignment = h->root.u.c.p->alignment_power;
1213
1214 if (ever != NULL
1215 && ! override
1216 && vernum > 1
1217 && (h->verinfo.verdef == NULL || definition))
1218 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1219 }
1220
1221 if (! (_bfd_generic_link_add_one_symbol
1222 (info, abfd, name, flags, sec, value, (const char *) NULL,
1223 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1224 goto error_return;
1225
1226 h = *sym_hash;
1227 while (h->root.type == bfd_link_hash_indirect
1228 || h->root.type == bfd_link_hash_warning)
1229 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1230 *sym_hash = h;
1231
1232 new_weakdef = false;
1233 if (dynamic
1234 && definition
1235 && (flags & BSF_WEAK) != 0
1236 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1237 && info->hash->creator->flavour == bfd_target_elf_flavour
1238 && h->weakdef == NULL)
1239 {
1240 /* Keep a list of all weak defined non function symbols from
1241 a dynamic object, using the weakdef field. Later in this
1242 function we will set the weakdef field to the correct
1243 value. We only put non-function symbols from dynamic
1244 objects on this list, because that happens to be the only
1245 time we need to know the normal symbol corresponding to a
1246 weak symbol, and the information is time consuming to
1247 figure out. If the weakdef field is not already NULL,
1248 then this symbol was already defined by some previous
1249 dynamic object, and we will be using that previous
1250 definition anyhow. */
1251
1252 h->weakdef = weaks;
1253 weaks = h;
1254 new_weakdef = true;
1255 }
1256
1257 /* Set the alignment of a common symbol. */
1258 if (sym.st_shndx == SHN_COMMON
1259 && h->root.type == bfd_link_hash_common)
1260 {
1261 unsigned int align;
1262
1263 align = bfd_log2 (sym.st_value);
1264 if (align > old_alignment)
1265 h->root.u.c.p->alignment_power = align;
1266 }
1267
1268 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1269 {
1270 int old_flags;
1271 boolean dynsym;
1272 int new_flag;
1273
1274 /* Remember the symbol size and type. */
1275 if (sym.st_size != 0
1276 && (definition || h->size == 0))
1277 {
1278 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1279 (*_bfd_error_handler)
1280 ("Warning: size of symbol `%s' changed from %lu to %lu in %s",
1281 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1282 bfd_get_filename (abfd));
1283
1284 h->size = sym.st_size;
1285 }
1286
1287 /* If this is a common symbol, then we always want H->SIZE
1288 to be the size of the common symbol. The code just above
1289 won't fix the size if a common symbol becomes larger. We
1290 don't warn about a size change here, because that is
1291 covered by --warn-common. */
1292 if (h->root.type == bfd_link_hash_common)
1293 h->size = h->root.u.c.size;
1294
1295 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1296 && (definition || h->type == STT_NOTYPE))
1297 {
1298 if (h->type != STT_NOTYPE
1299 && h->type != ELF_ST_TYPE (sym.st_info)
1300 && ! type_change_ok)
1301 (*_bfd_error_handler)
1302 ("Warning: type of symbol `%s' changed from %d to %d in %s",
1303 name, h->type, ELF_ST_TYPE (sym.st_info),
1304 bfd_get_filename (abfd));
1305
1306 h->type = ELF_ST_TYPE (sym.st_info);
1307 }
1308
1309 if (sym.st_other != 0
1310 && (definition || h->other == 0))
1311 h->other = sym.st_other;
1312
1313 /* Set a flag in the hash table entry indicating the type of
1314 reference or definition we just found. Keep a count of
1315 the number of dynamic symbols we find. A dynamic symbol
1316 is one which is referenced or defined by both a regular
1317 object and a shared object. */
1318 old_flags = h->elf_link_hash_flags;
1319 dynsym = false;
1320 if (! dynamic)
1321 {
1322 if (! definition)
1323 new_flag = ELF_LINK_HASH_REF_REGULAR;
1324 else
1325 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1326 if (info->shared
1327 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1328 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1329 dynsym = true;
1330 }
1331 else
1332 {
1333 if (! definition)
1334 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1335 else
1336 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1337 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1338 | ELF_LINK_HASH_REF_REGULAR)) != 0
1339 || (h->weakdef != NULL
1340 && ! new_weakdef
1341 && h->weakdef->dynindx != -1))
1342 dynsym = true;
1343 }
1344
1345 h->elf_link_hash_flags |= new_flag;
1346
1347 /* If this symbol has a version, and it is the default
1348 version, we create an indirect symbol from the default
1349 name to the fully decorated name. This will cause
1350 external references which do not specify a version to be
1351 bound to this version of the symbol. */
1352 if (definition)
1353 {
1354 char *p;
1355
1356 p = strchr (name, ELF_VER_CHR);
1357 if (p != NULL && p[1] == ELF_VER_CHR)
1358 {
1359 char *shortname;
1360 struct elf_link_hash_entry *hi;
1361 boolean override;
1362
1363 shortname = bfd_hash_allocate (&info->hash->table,
1364 p - name + 1);
1365 if (shortname == NULL)
1366 goto error_return;
1367 strncpy (shortname, name, p - name);
1368 shortname[p - name] = '\0';
1369
1370 /* We are going to create a new symbol. Merge it
1371 with any existing symbol with this name. For the
1372 purposes of the merge, act as though we were
1373 defining the symbol we just defined, although we
1374 actually going to define an indirect symbol. */
1375 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1376 &value, &hi, &override,
1377 &type_change_ok, &size_change_ok))
1378 goto error_return;
1379
1380 if (! override)
1381 {
1382 if (! (_bfd_generic_link_add_one_symbol
1383 (info, abfd, shortname, BSF_INDIRECT,
1384 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1385 collect, (struct bfd_link_hash_entry **) &hi)))
1386 goto error_return;
1387 }
1388 else
1389 {
1390 /* In this case the symbol named SHORTNAME is
1391 overriding the indirect symbol we want to
1392 add. We were planning on making SHORTNAME an
1393 indirect symbol referring to NAME. SHORTNAME
1394 is the name without a version. NAME is the
1395 fully versioned name, and it is the default
1396 version.
1397
1398 Overriding means that we already saw a
1399 definition for the symbol SHORTNAME in a
1400 regular object, and it is overriding the
1401 symbol defined in the dynamic object.
1402
1403 When this happens, we actually want to change
1404 NAME, the symbol we just added, to refer to
1405 SHORTNAME. This will cause references to
1406 NAME in the shared object to become
1407 references to SHORTNAME in the regular
1408 object. This is what we expect when we
1409 override a function in a shared object: that
1410 the references in the shared object will be
1411 mapped to the definition in the regular
1412 object. */
1413
1414 while (hi->root.type == bfd_link_hash_indirect
1415 || hi->root.type == bfd_link_hash_warning)
1416 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1417
1418 h->root.type = bfd_link_hash_indirect;
1419 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1420 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1421 {
1422 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1423 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1424 if (! _bfd_elf_link_record_dynamic_symbol (info, hi))
1425 goto error_return;
1426 }
1427
1428 /* Now set HI to H, so that the following code
1429 will set the other fields correctly. */
1430 hi = h;
1431 }
1432
1433 /* If there is a duplicate definition somewhere,
1434 then HI may not point to an indirect symbol. We
1435 will have reported an error to the user in that
1436 case. */
1437
1438 if (hi->root.type == bfd_link_hash_indirect)
1439 {
1440 struct elf_link_hash_entry *ht;
1441
1442 /* If the symbol became indirect, then we assume
1443 that we have not seen a definition before. */
1444 BFD_ASSERT ((hi->elf_link_hash_flags
1445 & (ELF_LINK_HASH_DEF_DYNAMIC
1446 | ELF_LINK_HASH_DEF_REGULAR))
1447 == 0);
1448
1449 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1450
1451 /* Copy down any references that we may have
1452 already seen to the symbol which just became
1453 indirect. */
1454 ht->elf_link_hash_flags |=
1455 (hi->elf_link_hash_flags
1456 & (ELF_LINK_HASH_REF_DYNAMIC
1457 | ELF_LINK_HASH_REF_REGULAR));
1458
1459 /* Copy over the global table offset entry.
1460 This may have been already set up by a
1461 check_relocs routine. */
1462 if (ht->got_offset == (bfd_vma) -1)
1463 {
1464 ht->got_offset = hi->got_offset;
1465 hi->got_offset = (bfd_vma) -1;
1466 }
1467 BFD_ASSERT (hi->got_offset == (bfd_vma) -1);
1468
1469 if (ht->dynindx == -1)
1470 {
1471 ht->dynindx = hi->dynindx;
1472 ht->dynstr_index = hi->dynstr_index;
1473 hi->dynindx = -1;
1474 hi->dynstr_index = 0;
1475 }
1476 BFD_ASSERT (hi->dynindx == -1);
1477
1478 /* FIXME: There may be other information to copy
1479 over for particular targets. */
1480
1481 /* See if the new flags lead us to realize that
1482 the symbol must be dynamic. */
1483 if (! dynsym)
1484 {
1485 if (! dynamic)
1486 {
1487 if (info->shared
1488 || ((hi->elf_link_hash_flags
1489 & ELF_LINK_HASH_REF_DYNAMIC)
1490 != 0))
1491 dynsym = true;
1492 }
1493 else
1494 {
1495 if ((hi->elf_link_hash_flags
1496 & ELF_LINK_HASH_REF_REGULAR) != 0)
1497 dynsym = true;
1498 }
1499 }
1500 }
1501
1502 /* We also need to define an indirection from the
1503 nondefault version of the symbol. */
1504
1505 shortname = bfd_hash_allocate (&info->hash->table,
1506 strlen (name));
1507 if (shortname == NULL)
1508 goto error_return;
1509 strncpy (shortname, name, p - name);
1510 strcpy (shortname + (p - name), p + 1);
1511
1512 /* Once again, merge with any existing symbol. */
1513 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1514 &value, &hi, &override,
1515 &type_change_ok, &size_change_ok))
1516 goto error_return;
1517
1518 if (override)
1519 {
1520 /* Here SHORTNAME is a versioned name, so we
1521 don't expect to see the type of override we
1522 do in the case above. */
1523 (*_bfd_error_handler)
1524 ("%s: warning: unexpected redefinition of `%s'",
1525 bfd_get_filename (abfd), shortname);
1526 }
1527 else
1528 {
1529 if (! (_bfd_generic_link_add_one_symbol
1530 (info, abfd, shortname, BSF_INDIRECT,
1531 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1532 collect, (struct bfd_link_hash_entry **) &hi)))
1533 goto error_return;
1534
1535 /* If there is a duplicate definition somewhere,
1536 then HI may not point to an indirect symbol.
1537 We will have reported an error to the user in
1538 that case. */
1539
1540 if (hi->root.type == bfd_link_hash_indirect)
1541 {
1542 /* If the symbol became indirect, then we
1543 assume that we have not seen a definition
1544 before. */
1545 BFD_ASSERT ((hi->elf_link_hash_flags
1546 & (ELF_LINK_HASH_DEF_DYNAMIC
1547 | ELF_LINK_HASH_DEF_REGULAR))
1548 == 0);
1549
1550 /* Copy down any references that we may have
1551 already seen to the symbol which just
1552 became indirect. */
1553 h->elf_link_hash_flags |=
1554 (hi->elf_link_hash_flags
1555 & (ELF_LINK_HASH_REF_DYNAMIC
1556 | ELF_LINK_HASH_REF_REGULAR));
1557
1558 /* Copy over the global table offset entry.
1559 This may have been already set up by a
1560 check_relocs routine. */
1561 if (h->got_offset == (bfd_vma) -1)
1562 {
1563 h->got_offset = hi->got_offset;
1564 hi->got_offset = (bfd_vma) -1;
1565 }
1566 BFD_ASSERT (hi->got_offset == (bfd_vma) -1);
1567
1568 if (h->dynindx == -1)
1569 {
1570 h->dynindx = hi->dynindx;
1571 h->dynstr_index = hi->dynstr_index;
1572 hi->dynindx = -1;
1573 hi->dynstr_index = 0;
1574 }
1575 BFD_ASSERT (hi->dynindx == -1);
1576
1577 /* FIXME: There may be other information to
1578 copy over for particular targets. */
1579
1580 /* See if the new flags lead us to realize
1581 that the symbol must be dynamic. */
1582 if (! dynsym)
1583 {
1584 if (! dynamic)
1585 {
1586 if (info->shared
1587 || ((hi->elf_link_hash_flags
1588 & ELF_LINK_HASH_REF_DYNAMIC)
1589 != 0))
1590 dynsym = true;
1591 }
1592 else
1593 {
1594 if ((hi->elf_link_hash_flags
1595 & ELF_LINK_HASH_REF_REGULAR) != 0)
1596 dynsym = true;
1597 }
1598 }
1599 }
1600 }
1601 }
1602 }
1603
1604 if (dynsym && h->dynindx == -1)
1605 {
1606 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1607 goto error_return;
1608 if (h->weakdef != NULL
1609 && ! new_weakdef
1610 && h->weakdef->dynindx == -1)
1611 {
1612 if (! _bfd_elf_link_record_dynamic_symbol (info,
1613 h->weakdef))
1614 goto error_return;
1615 }
1616 }
1617 }
1618 }
1619
1620 /* Now set the weakdefs field correctly for all the weak defined
1621 symbols we found. The only way to do this is to search all the
1622 symbols. Since we only need the information for non functions in
1623 dynamic objects, that's the only time we actually put anything on
1624 the list WEAKS. We need this information so that if a regular
1625 object refers to a symbol defined weakly in a dynamic object, the
1626 real symbol in the dynamic object is also put in the dynamic
1627 symbols; we also must arrange for both symbols to point to the
1628 same memory location. We could handle the general case of symbol
1629 aliasing, but a general symbol alias can only be generated in
1630 assembler code, handling it correctly would be very time
1631 consuming, and other ELF linkers don't handle general aliasing
1632 either. */
1633 while (weaks != NULL)
1634 {
1635 struct elf_link_hash_entry *hlook;
1636 asection *slook;
1637 bfd_vma vlook;
1638 struct elf_link_hash_entry **hpp;
1639 struct elf_link_hash_entry **hppend;
1640
1641 hlook = weaks;
1642 weaks = hlook->weakdef;
1643 hlook->weakdef = NULL;
1644
1645 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1646 || hlook->root.type == bfd_link_hash_defweak
1647 || hlook->root.type == bfd_link_hash_common
1648 || hlook->root.type == bfd_link_hash_indirect);
1649 slook = hlook->root.u.def.section;
1650 vlook = hlook->root.u.def.value;
1651
1652 hpp = elf_sym_hashes (abfd);
1653 hppend = hpp + extsymcount;
1654 for (; hpp < hppend; hpp++)
1655 {
1656 struct elf_link_hash_entry *h;
1657
1658 h = *hpp;
1659 if (h != NULL && h != hlook
1660 && h->root.type == bfd_link_hash_defined
1661 && h->root.u.def.section == slook
1662 && h->root.u.def.value == vlook)
1663 {
1664 hlook->weakdef = h;
1665
1666 /* If the weak definition is in the list of dynamic
1667 symbols, make sure the real definition is put there
1668 as well. */
1669 if (hlook->dynindx != -1
1670 && h->dynindx == -1)
1671 {
1672 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1673 goto error_return;
1674 }
1675
1676 /* If the real definition is in the list of dynamic
1677 symbols, make sure the weak definition is put there
1678 as well. If we don't do this, then the dynamic
1679 loader might not merge the entries for the real
1680 definition and the weak definition. */
1681 if (h->dynindx != -1
1682 && hlook->dynindx == -1)
1683 {
1684 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1685 goto error_return;
1686 }
1687
1688 break;
1689 }
1690 }
1691 }
1692
1693 if (buf != NULL)
1694 {
1695 free (buf);
1696 buf = NULL;
1697 }
1698
1699 if (extversym != NULL)
1700 {
1701 free (extversym);
1702 extversym = NULL;
1703 }
1704
1705 /* If this object is the same format as the output object, and it is
1706 not a shared library, then let the backend look through the
1707 relocs.
1708
1709 This is required to build global offset table entries and to
1710 arrange for dynamic relocs. It is not required for the
1711 particular common case of linking non PIC code, even when linking
1712 against shared libraries, but unfortunately there is no way of
1713 knowing whether an object file has been compiled PIC or not.
1714 Looking through the relocs is not particularly time consuming.
1715 The problem is that we must either (1) keep the relocs in memory,
1716 which causes the linker to require additional runtime memory or
1717 (2) read the relocs twice from the input file, which wastes time.
1718 This would be a good case for using mmap.
1719
1720 I have no idea how to handle linking PIC code into a file of a
1721 different format. It probably can't be done. */
1722 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1723 if (! dynamic
1724 && abfd->xvec == info->hash->creator
1725 && check_relocs != NULL)
1726 {
1727 asection *o;
1728
1729 for (o = abfd->sections; o != NULL; o = o->next)
1730 {
1731 Elf_Internal_Rela *internal_relocs;
1732 boolean ok;
1733
1734 if ((o->flags & SEC_RELOC) == 0
1735 || o->reloc_count == 0
1736 || ((info->strip == strip_all || info->strip == strip_debugger)
1737 && (o->flags & SEC_DEBUGGING) != 0)
1738 || bfd_is_abs_section (o->output_section))
1739 continue;
1740
1741 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1742 (abfd, o, (PTR) NULL,
1743 (Elf_Internal_Rela *) NULL,
1744 info->keep_memory));
1745 if (internal_relocs == NULL)
1746 goto error_return;
1747
1748 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1749
1750 if (! info->keep_memory)
1751 free (internal_relocs);
1752
1753 if (! ok)
1754 goto error_return;
1755 }
1756 }
1757
1758 /* If this is a non-traditional, non-relocateable link, try to
1759 optimize the handling of the .stab/.stabstr sections. */
1760 if (! dynamic
1761 && ! info->relocateable
1762 && ! info->traditional_format
1763 && info->hash->creator->flavour == bfd_target_elf_flavour
1764 && (info->strip != strip_all && info->strip != strip_debugger))
1765 {
1766 asection *stab, *stabstr;
1767
1768 stab = bfd_get_section_by_name (abfd, ".stab");
1769 if (stab != NULL)
1770 {
1771 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
1772
1773 if (stabstr != NULL)
1774 {
1775 struct bfd_elf_section_data *secdata;
1776
1777 secdata = elf_section_data (stab);
1778 if (! _bfd_link_section_stabs (abfd,
1779 &elf_hash_table (info)->stab_info,
1780 stab, stabstr,
1781 &secdata->stab_info))
1782 goto error_return;
1783 }
1784 }
1785 }
1786
1787 return true;
1788
1789 error_return:
1790 if (buf != NULL)
1791 free (buf);
1792 if (dynbuf != NULL)
1793 free (dynbuf);
1794 if (dynver != NULL)
1795 free (dynver);
1796 if (extversym != NULL)
1797 free (extversym);
1798 return false;
1799 }
1800
1801 /* Create some sections which will be filled in with dynamic linking
1802 information. ABFD is an input file which requires dynamic sections
1803 to be created. The dynamic sections take up virtual memory space
1804 when the final executable is run, so we need to create them before
1805 addresses are assigned to the output sections. We work out the
1806 actual contents and size of these sections later. */
1807
1808 boolean
1809 elf_link_create_dynamic_sections (abfd, info)
1810 bfd *abfd;
1811 struct bfd_link_info *info;
1812 {
1813 flagword flags;
1814 register asection *s;
1815 struct elf_link_hash_entry *h;
1816 struct elf_backend_data *bed;
1817
1818 if (elf_hash_table (info)->dynamic_sections_created)
1819 return true;
1820
1821 /* Make sure that all dynamic sections use the same input BFD. */
1822 if (elf_hash_table (info)->dynobj == NULL)
1823 elf_hash_table (info)->dynobj = abfd;
1824 else
1825 abfd = elf_hash_table (info)->dynobj;
1826
1827 /* Note that we set the SEC_IN_MEMORY flag for all of these
1828 sections. */
1829 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
1830 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1831
1832 /* A dynamically linked executable has a .interp section, but a
1833 shared library does not. */
1834 if (! info->shared)
1835 {
1836 s = bfd_make_section (abfd, ".interp");
1837 if (s == NULL
1838 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1839 return false;
1840 }
1841
1842 /* Create sections to hold version informations. These are removed
1843 if they are not needed. */
1844 s = bfd_make_section (abfd, ".gnu.version_d");
1845 if (s == NULL
1846 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1847 || ! bfd_set_section_alignment (abfd, s, 2))
1848 return false;
1849
1850 s = bfd_make_section (abfd, ".gnu.version");
1851 if (s == NULL
1852 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1853 || ! bfd_set_section_alignment (abfd, s, 1))
1854 return false;
1855
1856 s = bfd_make_section (abfd, ".gnu.version_r");
1857 if (s == NULL
1858 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1859 || ! bfd_set_section_alignment (abfd, s, 2))
1860 return false;
1861
1862 s = bfd_make_section (abfd, ".dynsym");
1863 if (s == NULL
1864 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1865 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1866 return false;
1867
1868 s = bfd_make_section (abfd, ".dynstr");
1869 if (s == NULL
1870 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1871 return false;
1872
1873 /* Create a strtab to hold the dynamic symbol names. */
1874 if (elf_hash_table (info)->dynstr == NULL)
1875 {
1876 elf_hash_table (info)->dynstr = elf_stringtab_init ();
1877 if (elf_hash_table (info)->dynstr == NULL)
1878 return false;
1879 }
1880
1881 s = bfd_make_section (abfd, ".dynamic");
1882 if (s == NULL
1883 || ! bfd_set_section_flags (abfd, s, flags)
1884 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1885 return false;
1886
1887 /* The special symbol _DYNAMIC is always set to the start of the
1888 .dynamic section. This call occurs before we have processed the
1889 symbols for any dynamic object, so we don't have to worry about
1890 overriding a dynamic definition. We could set _DYNAMIC in a
1891 linker script, but we only want to define it if we are, in fact,
1892 creating a .dynamic section. We don't want to define it if there
1893 is no .dynamic section, since on some ELF platforms the start up
1894 code examines it to decide how to initialize the process. */
1895 h = NULL;
1896 if (! (_bfd_generic_link_add_one_symbol
1897 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
1898 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
1899 (struct bfd_link_hash_entry **) &h)))
1900 return false;
1901 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
1902 h->type = STT_OBJECT;
1903
1904 if (info->shared
1905 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
1906 return false;
1907
1908 s = bfd_make_section (abfd, ".hash");
1909 if (s == NULL
1910 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1911 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1912 return false;
1913
1914 /* Let the backend create the rest of the sections. This lets the
1915 backend set the right flags. The backend will normally create
1916 the .got and .plt sections. */
1917 bed = get_elf_backend_data (abfd);
1918 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
1919 return false;
1920
1921 elf_hash_table (info)->dynamic_sections_created = true;
1922
1923 return true;
1924 }
1925
1926 /* Add an entry to the .dynamic table. */
1927
1928 boolean
1929 elf_add_dynamic_entry (info, tag, val)
1930 struct bfd_link_info *info;
1931 bfd_vma tag;
1932 bfd_vma val;
1933 {
1934 Elf_Internal_Dyn dyn;
1935 bfd *dynobj;
1936 asection *s;
1937 size_t newsize;
1938 bfd_byte *newcontents;
1939
1940 dynobj = elf_hash_table (info)->dynobj;
1941
1942 s = bfd_get_section_by_name (dynobj, ".dynamic");
1943 BFD_ASSERT (s != NULL);
1944
1945 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
1946 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
1947 if (newcontents == NULL)
1948 return false;
1949
1950 dyn.d_tag = tag;
1951 dyn.d_un.d_val = val;
1952 elf_swap_dyn_out (dynobj, &dyn,
1953 (Elf_External_Dyn *) (newcontents + s->_raw_size));
1954
1955 s->_raw_size = newsize;
1956 s->contents = newcontents;
1957
1958 return true;
1959 }
1960 \f
1961
1962 /* Read and swap the relocs for a section. They may have been cached.
1963 If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are not NULL,
1964 they are used as buffers to read into. They are known to be large
1965 enough. If the INTERNAL_RELOCS relocs argument is NULL, the return
1966 value is allocated using either malloc or bfd_alloc, according to
1967 the KEEP_MEMORY argument. */
1968
1969 Elf_Internal_Rela *
1970 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
1971 keep_memory)
1972 bfd *abfd;
1973 asection *o;
1974 PTR external_relocs;
1975 Elf_Internal_Rela *internal_relocs;
1976 boolean keep_memory;
1977 {
1978 Elf_Internal_Shdr *rel_hdr;
1979 PTR alloc1 = NULL;
1980 Elf_Internal_Rela *alloc2 = NULL;
1981
1982 if (elf_section_data (o)->relocs != NULL)
1983 return elf_section_data (o)->relocs;
1984
1985 if (o->reloc_count == 0)
1986 return NULL;
1987
1988 rel_hdr = &elf_section_data (o)->rel_hdr;
1989
1990 if (internal_relocs == NULL)
1991 {
1992 size_t size;
1993
1994 size = o->reloc_count * sizeof (Elf_Internal_Rela);
1995 if (keep_memory)
1996 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
1997 else
1998 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
1999 if (internal_relocs == NULL)
2000 goto error_return;
2001 }
2002
2003 if (external_relocs == NULL)
2004 {
2005 alloc1 = (PTR) bfd_malloc ((size_t) rel_hdr->sh_size);
2006 if (alloc1 == NULL)
2007 goto error_return;
2008 external_relocs = alloc1;
2009 }
2010
2011 if ((bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0)
2012 || (bfd_read (external_relocs, 1, rel_hdr->sh_size, abfd)
2013 != rel_hdr->sh_size))
2014 goto error_return;
2015
2016 /* Swap in the relocs. For convenience, we always produce an
2017 Elf_Internal_Rela array; if the relocs are Rel, we set the addend
2018 to 0. */
2019 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
2020 {
2021 Elf_External_Rel *erel;
2022 Elf_External_Rel *erelend;
2023 Elf_Internal_Rela *irela;
2024
2025 erel = (Elf_External_Rel *) external_relocs;
2026 erelend = erel + o->reloc_count;
2027 irela = internal_relocs;
2028 for (; erel < erelend; erel++, irela++)
2029 {
2030 Elf_Internal_Rel irel;
2031
2032 elf_swap_reloc_in (abfd, erel, &irel);
2033 irela->r_offset = irel.r_offset;
2034 irela->r_info = irel.r_info;
2035 irela->r_addend = 0;
2036 }
2037 }
2038 else
2039 {
2040 Elf_External_Rela *erela;
2041 Elf_External_Rela *erelaend;
2042 Elf_Internal_Rela *irela;
2043
2044 BFD_ASSERT (rel_hdr->sh_entsize == sizeof (Elf_External_Rela));
2045
2046 erela = (Elf_External_Rela *) external_relocs;
2047 erelaend = erela + o->reloc_count;
2048 irela = internal_relocs;
2049 for (; erela < erelaend; erela++, irela++)
2050 elf_swap_reloca_in (abfd, erela, irela);
2051 }
2052
2053 /* Cache the results for next time, if we can. */
2054 if (keep_memory)
2055 elf_section_data (o)->relocs = internal_relocs;
2056
2057 if (alloc1 != NULL)
2058 free (alloc1);
2059
2060 /* Don't free alloc2, since if it was allocated we are passing it
2061 back (under the name of internal_relocs). */
2062
2063 return internal_relocs;
2064
2065 error_return:
2066 if (alloc1 != NULL)
2067 free (alloc1);
2068 if (alloc2 != NULL)
2069 free (alloc2);
2070 return NULL;
2071 }
2072 \f
2073
2074 /* Record an assignment to a symbol made by a linker script. We need
2075 this in case some dynamic object refers to this symbol. */
2076
2077 /*ARGSUSED*/
2078 boolean
2079 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2080 bfd *output_bfd;
2081 struct bfd_link_info *info;
2082 const char *name;
2083 boolean provide;
2084 {
2085 struct elf_link_hash_entry *h;
2086
2087 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2088 return true;
2089
2090 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2091 if (h == NULL)
2092 return false;
2093
2094 if (h->root.type == bfd_link_hash_new)
2095 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2096
2097 /* If this symbol is being provided by the linker script, and it is
2098 currently defined by a dynamic object, but not by a regular
2099 object, then mark it as undefined so that the generic linker will
2100 force the correct value. */
2101 if (provide
2102 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2103 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2104 h->root.type = bfd_link_hash_undefined;
2105
2106 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2107 h->type = STT_OBJECT;
2108
2109 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2110 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2111 || info->shared)
2112 && h->dynindx == -1)
2113 {
2114 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2115 return false;
2116
2117 /* If this is a weak defined symbol, and we know a corresponding
2118 real symbol from the same dynamic object, make sure the real
2119 symbol is also made into a dynamic symbol. */
2120 if (h->weakdef != NULL
2121 && h->weakdef->dynindx == -1)
2122 {
2123 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2124 return false;
2125 }
2126 }
2127
2128 return true;
2129 }
2130 \f
2131 /* This structure is used to pass information to
2132 elf_link_assign_sym_version. */
2133
2134 struct elf_assign_sym_version_info
2135 {
2136 /* Output BFD. */
2137 bfd *output_bfd;
2138 /* General link information. */
2139 struct bfd_link_info *info;
2140 /* Version tree. */
2141 struct bfd_elf_version_tree *verdefs;
2142 /* Whether we are exporting all dynamic symbols. */
2143 boolean export_dynamic;
2144 /* Whether we removed any symbols from the dynamic symbol table. */
2145 boolean removed_dynamic;
2146 /* Whether we had a failure. */
2147 boolean failed;
2148 };
2149
2150 /* This structure is used to pass information to
2151 elf_link_find_version_dependencies. */
2152
2153 struct elf_find_verdep_info
2154 {
2155 /* Output BFD. */
2156 bfd *output_bfd;
2157 /* General link information. */
2158 struct bfd_link_info *info;
2159 /* The number of dependencies. */
2160 unsigned int vers;
2161 /* Whether we had a failure. */
2162 boolean failed;
2163 };
2164
2165 /* Array used to determine the number of hash table buckets to use
2166 based on the number of symbols there are. If there are fewer than
2167 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2168 fewer than 37 we use 17 buckets, and so forth. We never use more
2169 than 32771 buckets. */
2170
2171 static const size_t elf_buckets[] =
2172 {
2173 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2174 16411, 32771, 0
2175 };
2176
2177 /* Set up the sizes and contents of the ELF dynamic sections. This is
2178 called by the ELF linker emulation before_allocation routine. We
2179 must set the sizes of the sections before the linker sets the
2180 addresses of the various sections. */
2181
2182 boolean
2183 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2184 export_dynamic, filter_shlib,
2185 auxiliary_filters, info, sinterpptr,
2186 verdefs)
2187 bfd *output_bfd;
2188 const char *soname;
2189 const char *rpath;
2190 boolean export_dynamic;
2191 const char *filter_shlib;
2192 const char * const *auxiliary_filters;
2193 struct bfd_link_info *info;
2194 asection **sinterpptr;
2195 struct bfd_elf_version_tree *verdefs;
2196 {
2197 bfd_size_type soname_indx;
2198 bfd *dynobj;
2199 struct elf_backend_data *bed;
2200 bfd_size_type old_dynsymcount;
2201 struct elf_assign_sym_version_info asvinfo;
2202
2203 *sinterpptr = NULL;
2204
2205 soname_indx = -1;
2206
2207 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2208 return true;
2209
2210 /* The backend may have to create some sections regardless of whether
2211 we're dynamic or not. */
2212 bed = get_elf_backend_data (output_bfd);
2213 if (bed->elf_backend_always_size_sections
2214 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2215 return false;
2216
2217 dynobj = elf_hash_table (info)->dynobj;
2218
2219 /* If there were no dynamic objects in the link, there is nothing to
2220 do here. */
2221 if (dynobj == NULL)
2222 return true;
2223
2224 /* If we are supposed to export all symbols into the dynamic symbol
2225 table (this is not the normal case), then do so. */
2226 if (export_dynamic)
2227 {
2228 struct elf_info_failed eif;
2229
2230 eif.failed = false;
2231 eif.info = info;
2232 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2233 (PTR) &eif);
2234 if (eif.failed)
2235 return false;
2236 }
2237
2238 if (elf_hash_table (info)->dynamic_sections_created)
2239 {
2240 struct elf_info_failed eif;
2241 struct elf_link_hash_entry *h;
2242 bfd_size_type strsize;
2243
2244 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2245 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2246
2247 if (soname != NULL)
2248 {
2249 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2250 soname, true, true);
2251 if (soname_indx == (bfd_size_type) -1
2252 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2253 return false;
2254 }
2255
2256 if (info->symbolic)
2257 {
2258 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2259 return false;
2260 }
2261
2262 if (rpath != NULL)
2263 {
2264 bfd_size_type indx;
2265
2266 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2267 true, true);
2268 if (indx == (bfd_size_type) -1
2269 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2270 return false;
2271 }
2272
2273 if (filter_shlib != NULL)
2274 {
2275 bfd_size_type indx;
2276
2277 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2278 filter_shlib, true, true);
2279 if (indx == (bfd_size_type) -1
2280 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2281 return false;
2282 }
2283
2284 if (auxiliary_filters != NULL)
2285 {
2286 const char * const *p;
2287
2288 for (p = auxiliary_filters; *p != NULL; p++)
2289 {
2290 bfd_size_type indx;
2291
2292 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2293 *p, true, true);
2294 if (indx == (bfd_size_type) -1
2295 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2296 return false;
2297 }
2298 }
2299
2300 /* Attach all the symbols to their version information. */
2301 asvinfo.output_bfd = output_bfd;
2302 asvinfo.info = info;
2303 asvinfo.verdefs = verdefs;
2304 asvinfo.export_dynamic = export_dynamic;
2305 asvinfo.removed_dynamic = false;
2306 asvinfo.failed = false;
2307
2308 elf_link_hash_traverse (elf_hash_table (info),
2309 elf_link_assign_sym_version,
2310 (PTR) &asvinfo);
2311 if (asvinfo.failed)
2312 return false;
2313
2314 /* Find all symbols which were defined in a dynamic object and make
2315 the backend pick a reasonable value for them. */
2316 eif.failed = false;
2317 eif.info = info;
2318 elf_link_hash_traverse (elf_hash_table (info),
2319 elf_adjust_dynamic_symbol,
2320 (PTR) &eif);
2321 if (eif.failed)
2322 return false;
2323
2324 /* Add some entries to the .dynamic section. We fill in some of the
2325 values later, in elf_bfd_final_link, but we must add the entries
2326 now so that we know the final size of the .dynamic section. */
2327 h = elf_link_hash_lookup (elf_hash_table (info), "_init", false,
2328 false, false);
2329 if (h != NULL
2330 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2331 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2332 {
2333 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2334 return false;
2335 }
2336 h = elf_link_hash_lookup (elf_hash_table (info), "_fini", false,
2337 false, false);
2338 if (h != NULL
2339 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2340 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2341 {
2342 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2343 return false;
2344 }
2345 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2346 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2347 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2348 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2349 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2350 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2351 sizeof (Elf_External_Sym)))
2352 return false;
2353 }
2354
2355 /* The backend must work out the sizes of all the other dynamic
2356 sections. */
2357 old_dynsymcount = elf_hash_table (info)->dynsymcount;
2358 if (! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2359 return false;
2360
2361 if (elf_hash_table (info)->dynamic_sections_created)
2362 {
2363 size_t dynsymcount;
2364 asection *s;
2365 size_t i;
2366 size_t bucketcount = 0;
2367 Elf_Internal_Sym isym;
2368
2369 /* Set up the version definition section. */
2370 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2371 BFD_ASSERT (s != NULL);
2372
2373 /* We may have created additional version definitions if we are
2374 just linking a regular application. */
2375 verdefs = asvinfo.verdefs;
2376
2377 if (verdefs == NULL)
2378 {
2379 asection **spp;
2380
2381 /* Don't include this section in the output file. */
2382 for (spp = &output_bfd->sections;
2383 *spp != s->output_section;
2384 spp = &(*spp)->next)
2385 ;
2386 *spp = s->output_section->next;
2387 --output_bfd->section_count;
2388 }
2389 else
2390 {
2391 unsigned int cdefs;
2392 bfd_size_type size;
2393 struct bfd_elf_version_tree *t;
2394 bfd_byte *p;
2395 Elf_Internal_Verdef def;
2396 Elf_Internal_Verdaux defaux;
2397
2398 if (asvinfo.removed_dynamic)
2399 {
2400 /* Some dynamic symbols were changed to be local
2401 symbols. In this case, we renumber all of the
2402 dynamic symbols, so that we don't have a hole. If
2403 the backend changed dynsymcount, then assume that the
2404 new symbols are at the start. This is the case on
2405 the MIPS. FIXME: The names of the removed symbols
2406 will still be in the dynamic string table, wasting
2407 space. */
2408 elf_hash_table (info)->dynsymcount =
2409 1 + (elf_hash_table (info)->dynsymcount - old_dynsymcount);
2410 elf_link_hash_traverse (elf_hash_table (info),
2411 elf_link_renumber_dynsyms,
2412 (PTR) info);
2413 }
2414
2415 cdefs = 0;
2416 size = 0;
2417
2418 /* Make space for the base version. */
2419 size += sizeof (Elf_External_Verdef);
2420 size += sizeof (Elf_External_Verdaux);
2421 ++cdefs;
2422
2423 for (t = verdefs; t != NULL; t = t->next)
2424 {
2425 struct bfd_elf_version_deps *n;
2426
2427 size += sizeof (Elf_External_Verdef);
2428 size += sizeof (Elf_External_Verdaux);
2429 ++cdefs;
2430
2431 for (n = t->deps; n != NULL; n = n->next)
2432 size += sizeof (Elf_External_Verdaux);
2433 }
2434
2435 s->_raw_size = size;
2436 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2437 if (s->contents == NULL && s->_raw_size != 0)
2438 return false;
2439
2440 /* Fill in the version definition section. */
2441
2442 p = s->contents;
2443
2444 def.vd_version = VER_DEF_CURRENT;
2445 def.vd_flags = VER_FLG_BASE;
2446 def.vd_ndx = 1;
2447 def.vd_cnt = 1;
2448 def.vd_aux = sizeof (Elf_External_Verdef);
2449 def.vd_next = (sizeof (Elf_External_Verdef)
2450 + sizeof (Elf_External_Verdaux));
2451
2452 if (soname_indx != -1)
2453 {
2454 def.vd_hash = bfd_elf_hash ((const unsigned char *) soname);
2455 defaux.vda_name = soname_indx;
2456 }
2457 else
2458 {
2459 const char *name;
2460 bfd_size_type indx;
2461
2462 name = output_bfd->filename;
2463 def.vd_hash = bfd_elf_hash ((const unsigned char *) name);
2464 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2465 name, true, false);
2466 if (indx == (bfd_size_type) -1)
2467 return false;
2468 defaux.vda_name = indx;
2469 }
2470 defaux.vda_next = 0;
2471
2472 _bfd_elf_swap_verdef_out (output_bfd, &def,
2473 (Elf_External_Verdef *)p);
2474 p += sizeof (Elf_External_Verdef);
2475 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2476 (Elf_External_Verdaux *) p);
2477 p += sizeof (Elf_External_Verdaux);
2478
2479 for (t = verdefs; t != NULL; t = t->next)
2480 {
2481 unsigned int cdeps;
2482 struct bfd_elf_version_deps *n;
2483 struct elf_link_hash_entry *h;
2484
2485 cdeps = 0;
2486 for (n = t->deps; n != NULL; n = n->next)
2487 ++cdeps;
2488
2489 /* Add a symbol representing this version. */
2490 h = NULL;
2491 if (! (_bfd_generic_link_add_one_symbol
2492 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
2493 (bfd_vma) 0, (const char *) NULL, false,
2494 get_elf_backend_data (dynobj)->collect,
2495 (struct bfd_link_hash_entry **) &h)))
2496 return false;
2497 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
2498 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2499 h->type = STT_OBJECT;
2500 h->verinfo.vertree = t;
2501
2502 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2503 return false;
2504
2505 def.vd_version = VER_DEF_CURRENT;
2506 def.vd_flags = 0;
2507 if (t->globals == NULL && t->locals == NULL && ! t->used)
2508 def.vd_flags |= VER_FLG_WEAK;
2509 def.vd_ndx = t->vernum + 1;
2510 def.vd_cnt = cdeps + 1;
2511 def.vd_hash = bfd_elf_hash ((const unsigned char *) t->name);
2512 def.vd_aux = sizeof (Elf_External_Verdef);
2513 if (t->next != NULL)
2514 def.vd_next = (sizeof (Elf_External_Verdef)
2515 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
2516 else
2517 def.vd_next = 0;
2518
2519 _bfd_elf_swap_verdef_out (output_bfd, &def,
2520 (Elf_External_Verdef *) p);
2521 p += sizeof (Elf_External_Verdef);
2522
2523 defaux.vda_name = h->dynstr_index;
2524 if (t->deps == NULL)
2525 defaux.vda_next = 0;
2526 else
2527 defaux.vda_next = sizeof (Elf_External_Verdaux);
2528 t->name_indx = defaux.vda_name;
2529
2530 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2531 (Elf_External_Verdaux *) p);
2532 p += sizeof (Elf_External_Verdaux);
2533
2534 for (n = t->deps; n != NULL; n = n->next)
2535 {
2536 defaux.vda_name = n->version_needed->name_indx;
2537 if (n->next == NULL)
2538 defaux.vda_next = 0;
2539 else
2540 defaux.vda_next = sizeof (Elf_External_Verdaux);
2541
2542 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2543 (Elf_External_Verdaux *) p);
2544 p += sizeof (Elf_External_Verdaux);
2545 }
2546 }
2547
2548 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
2549 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
2550 return false;
2551
2552 elf_tdata (output_bfd)->cverdefs = cdefs;
2553 }
2554
2555 /* Work out the size of the version reference section. */
2556
2557 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
2558 BFD_ASSERT (s != NULL);
2559 {
2560 struct elf_find_verdep_info sinfo;
2561
2562 sinfo.output_bfd = output_bfd;
2563 sinfo.info = info;
2564 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
2565 if (sinfo.vers == 0)
2566 sinfo.vers = 1;
2567 sinfo.failed = false;
2568
2569 elf_link_hash_traverse (elf_hash_table (info),
2570 elf_link_find_version_dependencies,
2571 (PTR) &sinfo);
2572
2573 if (elf_tdata (output_bfd)->verref == NULL)
2574 {
2575 asection **spp;
2576
2577 /* We don't have any version definitions, so we can just
2578 remove the section. */
2579
2580 for (spp = &output_bfd->sections;
2581 *spp != s->output_section;
2582 spp = &(*spp)->next)
2583 ;
2584 *spp = s->output_section->next;
2585 --output_bfd->section_count;
2586 }
2587 else
2588 {
2589 Elf_Internal_Verneed *t;
2590 unsigned int size;
2591 unsigned int crefs;
2592 bfd_byte *p;
2593
2594 /* Build the version definition section. */
2595 size = 0;
2596 crefs = 0;
2597 for (t = elf_tdata (output_bfd)->verref;
2598 t != NULL;
2599 t = t->vn_nextref)
2600 {
2601 Elf_Internal_Vernaux *a;
2602
2603 size += sizeof (Elf_External_Verneed);
2604 ++crefs;
2605 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2606 size += sizeof (Elf_External_Vernaux);
2607 }
2608
2609 s->_raw_size = size;
2610 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
2611 if (s->contents == NULL)
2612 return false;
2613
2614 p = s->contents;
2615 for (t = elf_tdata (output_bfd)->verref;
2616 t != NULL;
2617 t = t->vn_nextref)
2618 {
2619 unsigned int caux;
2620 Elf_Internal_Vernaux *a;
2621 bfd_size_type indx;
2622
2623 caux = 0;
2624 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2625 ++caux;
2626
2627 t->vn_version = VER_NEED_CURRENT;
2628 t->vn_cnt = caux;
2629 if (elf_dt_name (t->vn_bfd) != NULL)
2630 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2631 elf_dt_name (t->vn_bfd),
2632 true, false);
2633 else
2634 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2635 t->vn_bfd->filename, true, false);
2636 if (indx == (bfd_size_type) -1)
2637 return false;
2638 t->vn_file = indx;
2639 t->vn_aux = sizeof (Elf_External_Verneed);
2640 if (t->vn_nextref == NULL)
2641 t->vn_next = 0;
2642 else
2643 t->vn_next = (sizeof (Elf_External_Verneed)
2644 + caux * sizeof (Elf_External_Vernaux));
2645
2646 _bfd_elf_swap_verneed_out (output_bfd, t,
2647 (Elf_External_Verneed *) p);
2648 p += sizeof (Elf_External_Verneed);
2649
2650 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2651 {
2652 a->vna_hash = bfd_elf_hash ((const unsigned char *)
2653 a->vna_nodename);
2654 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2655 a->vna_nodename, true, false);
2656 if (indx == (bfd_size_type) -1)
2657 return false;
2658 a->vna_name = indx;
2659 if (a->vna_nextptr == NULL)
2660 a->vna_next = 0;
2661 else
2662 a->vna_next = sizeof (Elf_External_Vernaux);
2663
2664 _bfd_elf_swap_vernaux_out (output_bfd, a,
2665 (Elf_External_Vernaux *) p);
2666 p += sizeof (Elf_External_Vernaux);
2667 }
2668 }
2669
2670 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
2671 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
2672 return false;
2673
2674 elf_tdata (output_bfd)->cverrefs = crefs;
2675 }
2676 }
2677
2678 dynsymcount = elf_hash_table (info)->dynsymcount;
2679
2680 /* Work out the size of the symbol version section. */
2681 s = bfd_get_section_by_name (dynobj, ".gnu.version");
2682 BFD_ASSERT (s != NULL);
2683 if (dynsymcount == 0
2684 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
2685 {
2686 asection **spp;
2687
2688 /* We don't need any symbol versions; just discard the
2689 section. */
2690 for (spp = &output_bfd->sections;
2691 *spp != s->output_section;
2692 spp = &(*spp)->next)
2693 ;
2694 *spp = s->output_section->next;
2695 --output_bfd->section_count;
2696 }
2697 else
2698 {
2699 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
2700 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
2701 if (s->contents == NULL)
2702 return false;
2703
2704 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
2705 return false;
2706 }
2707
2708 /* Set the size of the .dynsym and .hash sections. We counted
2709 the number of dynamic symbols in elf_link_add_object_symbols.
2710 We will build the contents of .dynsym and .hash when we build
2711 the final symbol table, because until then we do not know the
2712 correct value to give the symbols. We built the .dynstr
2713 section as we went along in elf_link_add_object_symbols. */
2714 s = bfd_get_section_by_name (dynobj, ".dynsym");
2715 BFD_ASSERT (s != NULL);
2716 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
2717 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2718 if (s->contents == NULL && s->_raw_size != 0)
2719 return false;
2720
2721 /* The first entry in .dynsym is a dummy symbol. */
2722 isym.st_value = 0;
2723 isym.st_size = 0;
2724 isym.st_name = 0;
2725 isym.st_info = 0;
2726 isym.st_other = 0;
2727 isym.st_shndx = 0;
2728 elf_swap_symbol_out (output_bfd, &isym,
2729 (PTR) (Elf_External_Sym *) s->contents);
2730
2731 for (i = 0; elf_buckets[i] != 0; i++)
2732 {
2733 bucketcount = elf_buckets[i];
2734 if (dynsymcount < elf_buckets[i + 1])
2735 break;
2736 }
2737
2738 s = bfd_get_section_by_name (dynobj, ".hash");
2739 BFD_ASSERT (s != NULL);
2740 s->_raw_size = (2 + bucketcount + dynsymcount) * (ARCH_SIZE / 8);
2741 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2742 if (s->contents == NULL)
2743 return false;
2744 memset (s->contents, 0, (size_t) s->_raw_size);
2745
2746 put_word (output_bfd, bucketcount, s->contents);
2747 put_word (output_bfd, dynsymcount, s->contents + (ARCH_SIZE / 8));
2748
2749 elf_hash_table (info)->bucketcount = bucketcount;
2750
2751 s = bfd_get_section_by_name (dynobj, ".dynstr");
2752 BFD_ASSERT (s != NULL);
2753 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2754
2755 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
2756 return false;
2757 }
2758
2759 return true;
2760 }
2761 \f
2762 /* Fix up the flags for a symbol. This handles various cases which
2763 can only be fixed after all the input files are seen. This is
2764 currently called by both adjust_dynamic_symbol and
2765 assign_sym_version, which is unnecessary but perhaps more robust in
2766 the face of future changes. */
2767
2768 static boolean
2769 elf_fix_symbol_flags (h, eif)
2770 struct elf_link_hash_entry *h;
2771 struct elf_info_failed *eif;
2772 {
2773 /* If this symbol was mentioned in a non-ELF file, try to set
2774 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2775 permit a non-ELF file to correctly refer to a symbol defined in
2776 an ELF dynamic object. */
2777 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
2778 {
2779 if (h->root.type != bfd_link_hash_defined
2780 && h->root.type != bfd_link_hash_defweak)
2781 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2782 else
2783 {
2784 if (h->root.u.def.section->owner != NULL
2785 && (bfd_get_flavour (h->root.u.def.section->owner)
2786 == bfd_target_elf_flavour))
2787 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2788 else
2789 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2790 }
2791
2792 if (h->dynindx == -1
2793 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2794 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
2795 {
2796 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
2797 {
2798 eif->failed = true;
2799 return false;
2800 }
2801 }
2802 }
2803
2804 /* If this is a final link, and the symbol was defined as a common
2805 symbol in a regular object file, and there was no definition in
2806 any dynamic object, then the linker will have allocated space for
2807 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
2808 flag will not have been set. */
2809 if (h->root.type == bfd_link_hash_defined
2810 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
2811 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
2812 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2813 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2814 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2815
2816 /* If -Bsymbolic was used (which means to bind references to global
2817 symbols to the definition within the shared object), and this
2818 symbol was defined in a regular object, then it actually doesn't
2819 need a PLT entry. */
2820 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
2821 && eif->info->shared
2822 && eif->info->symbolic
2823 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2824 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
2825
2826 return true;
2827 }
2828
2829 /* Make the backend pick a good value for a dynamic symbol. This is
2830 called via elf_link_hash_traverse, and also calls itself
2831 recursively. */
2832
2833 static boolean
2834 elf_adjust_dynamic_symbol (h, data)
2835 struct elf_link_hash_entry *h;
2836 PTR data;
2837 {
2838 struct elf_info_failed *eif = (struct elf_info_failed *) data;
2839 bfd *dynobj;
2840 struct elf_backend_data *bed;
2841
2842 /* Ignore indirect symbols. These are added by the versioning code. */
2843 if (h->root.type == bfd_link_hash_indirect)
2844 return true;
2845
2846 /* Fix the symbol flags. */
2847 if (! elf_fix_symbol_flags (h, eif))
2848 return false;
2849
2850 /* If this symbol does not require a PLT entry, and it is not
2851 defined by a dynamic object, or is not referenced by a regular
2852 object, ignore it. We do have to handle a weak defined symbol,
2853 even if no regular object refers to it, if we decided to add it
2854 to the dynamic symbol table. FIXME: Do we normally need to worry
2855 about symbols which are defined by one dynamic object and
2856 referenced by another one? */
2857 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
2858 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
2859 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2860 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
2861 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
2862 return true;
2863
2864 /* If we've already adjusted this symbol, don't do it again. This
2865 can happen via a recursive call. */
2866 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
2867 return true;
2868
2869 /* Don't look at this symbol again. Note that we must set this
2870 after checking the above conditions, because we may look at a
2871 symbol once, decide not to do anything, and then get called
2872 recursively later after REF_REGULAR is set below. */
2873 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
2874
2875 /* If this is a weak definition, and we know a real definition, and
2876 the real symbol is not itself defined by a regular object file,
2877 then get a good value for the real definition. We handle the
2878 real symbol first, for the convenience of the backend routine.
2879
2880 Note that there is a confusing case here. If the real definition
2881 is defined by a regular object file, we don't get the real symbol
2882 from the dynamic object, but we do get the weak symbol. If the
2883 processor backend uses a COPY reloc, then if some routine in the
2884 dynamic object changes the real symbol, we will not see that
2885 change in the corresponding weak symbol. This is the way other
2886 ELF linkers work as well, and seems to be a result of the shared
2887 library model.
2888
2889 I will clarify this issue. Most SVR4 shared libraries define the
2890 variable _timezone and define timezone as a weak synonym. The
2891 tzset call changes _timezone. If you write
2892 extern int timezone;
2893 int _timezone = 5;
2894 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2895 you might expect that, since timezone is a synonym for _timezone,
2896 the same number will print both times. However, if the processor
2897 backend uses a COPY reloc, then actually timezone will be copied
2898 into your process image, and, since you define _timezone
2899 yourself, _timezone will not. Thus timezone and _timezone will
2900 wind up at different memory locations. The tzset call will set
2901 _timezone, leaving timezone unchanged. */
2902
2903 if (h->weakdef != NULL)
2904 {
2905 struct elf_link_hash_entry *weakdef;
2906
2907 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2908 || h->root.type == bfd_link_hash_defweak);
2909 weakdef = h->weakdef;
2910 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2911 || weakdef->root.type == bfd_link_hash_defweak);
2912 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
2913 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2914 {
2915 /* This symbol is defined by a regular object file, so we
2916 will not do anything special. Clear weakdef for the
2917 convenience of the processor backend. */
2918 h->weakdef = NULL;
2919 }
2920 else
2921 {
2922 /* There is an implicit reference by a regular object file
2923 via the weak symbol. */
2924 weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2925 if (! elf_adjust_dynamic_symbol (weakdef, (PTR) eif))
2926 return false;
2927 }
2928 }
2929
2930 dynobj = elf_hash_table (eif->info)->dynobj;
2931 bed = get_elf_backend_data (dynobj);
2932 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2933 {
2934 eif->failed = true;
2935 return false;
2936 }
2937
2938 return true;
2939 }
2940 \f
2941 /* This routine is used to export all defined symbols into the dynamic
2942 symbol table. It is called via elf_link_hash_traverse. */
2943
2944 static boolean
2945 elf_export_symbol (h, data)
2946 struct elf_link_hash_entry *h;
2947 PTR data;
2948 {
2949 struct elf_info_failed *eif = (struct elf_info_failed *) data;
2950
2951 /* Ignore indirect symbols. These are added by the versioning code. */
2952 if (h->root.type == bfd_link_hash_indirect)
2953 return true;
2954
2955 if (h->dynindx == -1
2956 && (h->elf_link_hash_flags
2957 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
2958 {
2959 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
2960 {
2961 eif->failed = true;
2962 return false;
2963 }
2964 }
2965
2966 return true;
2967 }
2968 \f
2969 /* Look through the symbols which are defined in other shared
2970 libraries and referenced here. Update the list of version
2971 dependencies. This will be put into the .gnu.version_r section.
2972 This function is called via elf_link_hash_traverse. */
2973
2974 static boolean
2975 elf_link_find_version_dependencies (h, data)
2976 struct elf_link_hash_entry *h;
2977 PTR data;
2978 {
2979 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
2980 Elf_Internal_Verneed *t;
2981 Elf_Internal_Vernaux *a;
2982
2983 /* We only care about symbols defined in shared objects with version
2984 information. */
2985 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2986 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
2987 || h->dynindx == -1
2988 || h->verinfo.verdef == NULL)
2989 return true;
2990
2991 /* See if we already know about this version. */
2992 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
2993 {
2994 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
2995 continue;
2996
2997 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2998 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
2999 return true;
3000
3001 break;
3002 }
3003
3004 /* This is a new version. Add it to tree we are building. */
3005
3006 if (t == NULL)
3007 {
3008 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3009 if (t == NULL)
3010 {
3011 rinfo->failed = true;
3012 return false;
3013 }
3014
3015 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3016 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3017 elf_tdata (rinfo->output_bfd)->verref = t;
3018 }
3019
3020 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3021
3022 /* Note that we are copying a string pointer here, and testing it
3023 above. If bfd_elf_string_from_elf_section is ever changed to
3024 discard the string data when low in memory, this will have to be
3025 fixed. */
3026 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3027
3028 a->vna_flags = h->verinfo.verdef->vd_flags;
3029 a->vna_nextptr = t->vn_auxptr;
3030
3031 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3032 ++rinfo->vers;
3033
3034 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3035
3036 t->vn_auxptr = a;
3037
3038 return true;
3039 }
3040
3041 /* Figure out appropriate versions for all the symbols. We may not
3042 have the version number script until we have read all of the input
3043 files, so until that point we don't know which symbols should be
3044 local. This function is called via elf_link_hash_traverse. */
3045
3046 static boolean
3047 elf_link_assign_sym_version (h, data)
3048 struct elf_link_hash_entry *h;
3049 PTR data;
3050 {
3051 struct elf_assign_sym_version_info *sinfo =
3052 (struct elf_assign_sym_version_info *) data;
3053 struct bfd_link_info *info = sinfo->info;
3054 struct elf_info_failed eif;
3055 char *p;
3056
3057 /* Fix the symbol flags. */
3058 eif.failed = false;
3059 eif.info = info;
3060 if (! elf_fix_symbol_flags (h, &eif))
3061 {
3062 if (eif.failed)
3063 sinfo->failed = true;
3064 return false;
3065 }
3066
3067 /* We only need version numbers for symbols defined in regular
3068 objects. */
3069 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3070 return true;
3071
3072 p = strchr (h->root.root.string, ELF_VER_CHR);
3073 if (p != NULL && h->verinfo.vertree == NULL)
3074 {
3075 struct bfd_elf_version_tree *t;
3076 boolean hidden;
3077
3078 hidden = true;
3079
3080 /* There are two consecutive ELF_VER_CHR characters if this is
3081 not a hidden symbol. */
3082 ++p;
3083 if (*p == ELF_VER_CHR)
3084 {
3085 hidden = false;
3086 ++p;
3087 }
3088
3089 /* If there is no version string, we can just return out. */
3090 if (*p == '\0')
3091 {
3092 if (hidden)
3093 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3094 return true;
3095 }
3096
3097 /* Look for the version. If we find it, it is no longer weak. */
3098 for (t = sinfo->verdefs; t != NULL; t = t->next)
3099 {
3100 if (strcmp (t->name, p) == 0)
3101 {
3102 h->verinfo.vertree = t;
3103 t->used = true;
3104
3105 /* See if there is anything to force this symbol to
3106 local scope. */
3107 if (t->locals != NULL)
3108 {
3109 int len;
3110 char *alc;
3111 struct bfd_elf_version_expr *d;
3112
3113 len = p - h->root.root.string;
3114 alc = bfd_alloc (sinfo->output_bfd, len);
3115 if (alc == NULL)
3116 return false;
3117 strncpy (alc, h->root.root.string, len - 1);
3118 alc[len - 1] = '\0';
3119 if (alc[len - 2] == ELF_VER_CHR)
3120 alc[len - 2] = '\0';
3121
3122 for (d = t->locals; d != NULL; d = d->next)
3123 {
3124 if ((d->match[0] == '*' && d->match[1] == '\0')
3125 || fnmatch (d->match, alc, 0) == 0)
3126 {
3127 if (h->dynindx != -1
3128 && info->shared
3129 && ! sinfo->export_dynamic)
3130 {
3131 sinfo->removed_dynamic = true;
3132 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3133 h->elf_link_hash_flags &=~
3134 ELF_LINK_HASH_NEEDS_PLT;
3135 h->dynindx = -1;
3136 /* FIXME: The name of the symbol has
3137 already been recorded in the dynamic
3138 string table section. */
3139 }
3140
3141 break;
3142 }
3143 }
3144
3145 bfd_release (sinfo->output_bfd, alc);
3146 }
3147
3148 break;
3149 }
3150 }
3151
3152 /* If we are building an application, we need to create a
3153 version node for this version. */
3154 if (t == NULL && ! info->shared)
3155 {
3156 struct bfd_elf_version_tree **pp;
3157 int version_index;
3158
3159 /* If we aren't going to export this symbol, we don't need
3160 to worry about it. */
3161 if (h->dynindx == -1)
3162 return true;
3163
3164 t = ((struct bfd_elf_version_tree *)
3165 bfd_alloc (sinfo->output_bfd, sizeof *t));
3166 if (t == NULL)
3167 {
3168 sinfo->failed = true;
3169 return false;
3170 }
3171
3172 t->next = NULL;
3173 t->name = p;
3174 t->globals = NULL;
3175 t->locals = NULL;
3176 t->deps = NULL;
3177 t->name_indx = (unsigned int) -1;
3178 t->used = true;
3179
3180 version_index = 1;
3181 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3182 ++version_index;
3183 t->vernum = version_index;
3184
3185 *pp = t;
3186
3187 h->verinfo.vertree = t;
3188 }
3189 else if (t == NULL)
3190 {
3191 /* We could not find the version for a symbol when
3192 generating a shared archive. Return an error. */
3193 (*_bfd_error_handler)
3194 ("%s: undefined version name %s",
3195 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3196 bfd_set_error (bfd_error_bad_value);
3197 sinfo->failed = true;
3198 return false;
3199 }
3200
3201 if (hidden)
3202 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3203 }
3204
3205 /* If we don't have a version for this symbol, see if we can find
3206 something. */
3207 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3208 {
3209 struct bfd_elf_version_tree *t;
3210 struct bfd_elf_version_tree *deflt;
3211 struct bfd_elf_version_expr *d;
3212
3213 /* See if can find what version this symbol is in. If the
3214 symbol is supposed to be local, then don't actually register
3215 it. */
3216 deflt = NULL;
3217 for (t = sinfo->verdefs; t != NULL; t = t->next)
3218 {
3219 if (t->globals != NULL)
3220 {
3221 for (d = t->globals; d != NULL; d = d->next)
3222 {
3223 if (fnmatch (d->match, h->root.root.string, 0) == 0)
3224 {
3225 h->verinfo.vertree = t;
3226 break;
3227 }
3228 }
3229
3230 if (d != NULL)
3231 break;
3232 }
3233
3234 if (t->locals != NULL)
3235 {
3236 for (d = t->locals; d != NULL; d = d->next)
3237 {
3238 if (d->match[0] == '*' && d->match[1] == '\0')
3239 deflt = t;
3240 else if (fnmatch (d->match, h->root.root.string, 0) == 0)
3241 {
3242 h->verinfo.vertree = t;
3243 if (h->dynindx != -1
3244 && info->shared
3245 && ! sinfo->export_dynamic)
3246 {
3247 sinfo->removed_dynamic = true;
3248 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3249 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3250 h->dynindx = -1;
3251 /* FIXME: The name of the symbol has already
3252 been recorded in the dynamic string table
3253 section. */
3254 }
3255 break;
3256 }
3257 }
3258
3259 if (d != NULL)
3260 break;
3261 }
3262 }
3263
3264 if (deflt != NULL && h->verinfo.vertree == NULL)
3265 {
3266 h->verinfo.vertree = deflt;
3267 if (h->dynindx != -1
3268 && info->shared
3269 && ! sinfo->export_dynamic)
3270 {
3271 sinfo->removed_dynamic = true;
3272 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3273 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3274 h->dynindx = -1;
3275 /* FIXME: The name of the symbol has already been
3276 recorded in the dynamic string table section. */
3277 }
3278 }
3279 }
3280
3281 return true;
3282 }
3283
3284 /* This function is used to renumber the dynamic symbols, if some of
3285 them are removed because they are marked as local. This is called
3286 via elf_link_hash_traverse. */
3287
3288 static boolean
3289 elf_link_renumber_dynsyms (h, data)
3290 struct elf_link_hash_entry *h;
3291 PTR data;
3292 {
3293 struct bfd_link_info *info = (struct bfd_link_info *) data;
3294
3295 if (h->dynindx != -1)
3296 {
3297 h->dynindx = elf_hash_table (info)->dynsymcount;
3298 ++elf_hash_table (info)->dynsymcount;
3299 }
3300
3301 return true;
3302 }
3303 \f
3304 /* Final phase of ELF linker. */
3305
3306 /* A structure we use to avoid passing large numbers of arguments. */
3307
3308 struct elf_final_link_info
3309 {
3310 /* General link information. */
3311 struct bfd_link_info *info;
3312 /* Output BFD. */
3313 bfd *output_bfd;
3314 /* Symbol string table. */
3315 struct bfd_strtab_hash *symstrtab;
3316 /* .dynsym section. */
3317 asection *dynsym_sec;
3318 /* .hash section. */
3319 asection *hash_sec;
3320 /* symbol version section (.gnu.version). */
3321 asection *symver_sec;
3322 /* Buffer large enough to hold contents of any section. */
3323 bfd_byte *contents;
3324 /* Buffer large enough to hold external relocs of any section. */
3325 PTR external_relocs;
3326 /* Buffer large enough to hold internal relocs of any section. */
3327 Elf_Internal_Rela *internal_relocs;
3328 /* Buffer large enough to hold external local symbols of any input
3329 BFD. */
3330 Elf_External_Sym *external_syms;
3331 /* Buffer large enough to hold internal local symbols of any input
3332 BFD. */
3333 Elf_Internal_Sym *internal_syms;
3334 /* Array large enough to hold a symbol index for each local symbol
3335 of any input BFD. */
3336 long *indices;
3337 /* Array large enough to hold a section pointer for each local
3338 symbol of any input BFD. */
3339 asection **sections;
3340 /* Buffer to hold swapped out symbols. */
3341 Elf_External_Sym *symbuf;
3342 /* Number of swapped out symbols in buffer. */
3343 size_t symbuf_count;
3344 /* Number of symbols which fit in symbuf. */
3345 size_t symbuf_size;
3346 };
3347
3348 static boolean elf_link_output_sym
3349 PARAMS ((struct elf_final_link_info *, const char *,
3350 Elf_Internal_Sym *, asection *));
3351 static boolean elf_link_flush_output_syms
3352 PARAMS ((struct elf_final_link_info *));
3353 static boolean elf_link_output_extsym
3354 PARAMS ((struct elf_link_hash_entry *, PTR));
3355 static boolean elf_link_input_bfd
3356 PARAMS ((struct elf_final_link_info *, bfd *));
3357 static boolean elf_reloc_link_order
3358 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3359 struct bfd_link_order *));
3360
3361 /* This struct is used to pass information to elf_link_output_extsym. */
3362
3363 struct elf_outext_info
3364 {
3365 boolean failed;
3366 boolean localsyms;
3367 struct elf_final_link_info *finfo;
3368 };
3369
3370 /* Do the final step of an ELF link. */
3371
3372 boolean
3373 elf_bfd_final_link (abfd, info)
3374 bfd *abfd;
3375 struct bfd_link_info *info;
3376 {
3377 boolean dynamic;
3378 bfd *dynobj;
3379 struct elf_final_link_info finfo;
3380 register asection *o;
3381 register struct bfd_link_order *p;
3382 register bfd *sub;
3383 size_t max_contents_size;
3384 size_t max_external_reloc_size;
3385 size_t max_internal_reloc_count;
3386 size_t max_sym_count;
3387 file_ptr off;
3388 Elf_Internal_Sym elfsym;
3389 unsigned int i;
3390 Elf_Internal_Shdr *symtab_hdr;
3391 Elf_Internal_Shdr *symstrtab_hdr;
3392 struct elf_backend_data *bed = get_elf_backend_data (abfd);
3393 struct elf_outext_info eoinfo;
3394
3395 if (info->shared)
3396 abfd->flags |= DYNAMIC;
3397
3398 dynamic = elf_hash_table (info)->dynamic_sections_created;
3399 dynobj = elf_hash_table (info)->dynobj;
3400
3401 finfo.info = info;
3402 finfo.output_bfd = abfd;
3403 finfo.symstrtab = elf_stringtab_init ();
3404 if (finfo.symstrtab == NULL)
3405 return false;
3406
3407 if (! dynamic)
3408 {
3409 finfo.dynsym_sec = NULL;
3410 finfo.hash_sec = NULL;
3411 finfo.symver_sec = NULL;
3412 }
3413 else
3414 {
3415 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
3416 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
3417 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
3418 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
3419 /* Note that it is OK if symver_sec is NULL. */
3420 }
3421
3422 finfo.contents = NULL;
3423 finfo.external_relocs = NULL;
3424 finfo.internal_relocs = NULL;
3425 finfo.external_syms = NULL;
3426 finfo.internal_syms = NULL;
3427 finfo.indices = NULL;
3428 finfo.sections = NULL;
3429 finfo.symbuf = NULL;
3430 finfo.symbuf_count = 0;
3431
3432 /* Count up the number of relocations we will output for each output
3433 section, so that we know the sizes of the reloc sections. We
3434 also figure out some maximum sizes. */
3435 max_contents_size = 0;
3436 max_external_reloc_size = 0;
3437 max_internal_reloc_count = 0;
3438 max_sym_count = 0;
3439 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
3440 {
3441 o->reloc_count = 0;
3442
3443 for (p = o->link_order_head; p != NULL; p = p->next)
3444 {
3445 if (p->type == bfd_section_reloc_link_order
3446 || p->type == bfd_symbol_reloc_link_order)
3447 ++o->reloc_count;
3448 else if (p->type == bfd_indirect_link_order)
3449 {
3450 asection *sec;
3451
3452 sec = p->u.indirect.section;
3453
3454 /* Mark all sections which are to be included in the
3455 link. This will normally be every section. We need
3456 to do this so that we can identify any sections which
3457 the linker has decided to not include. */
3458 sec->linker_mark = true;
3459
3460 if (info->relocateable)
3461 o->reloc_count += sec->reloc_count;
3462
3463 if (sec->_raw_size > max_contents_size)
3464 max_contents_size = sec->_raw_size;
3465 if (sec->_cooked_size > max_contents_size)
3466 max_contents_size = sec->_cooked_size;
3467
3468 /* We are interested in just local symbols, not all
3469 symbols. */
3470 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
3471 && (sec->owner->flags & DYNAMIC) == 0)
3472 {
3473 size_t sym_count;
3474
3475 if (elf_bad_symtab (sec->owner))
3476 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
3477 / sizeof (Elf_External_Sym));
3478 else
3479 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
3480
3481 if (sym_count > max_sym_count)
3482 max_sym_count = sym_count;
3483
3484 if ((sec->flags & SEC_RELOC) != 0)
3485 {
3486 size_t ext_size;
3487
3488 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
3489 if (ext_size > max_external_reloc_size)
3490 max_external_reloc_size = ext_size;
3491 if (sec->reloc_count > max_internal_reloc_count)
3492 max_internal_reloc_count = sec->reloc_count;
3493 }
3494 }
3495 }
3496 }
3497
3498 if (o->reloc_count > 0)
3499 o->flags |= SEC_RELOC;
3500 else
3501 {
3502 /* Explicitly clear the SEC_RELOC flag. The linker tends to
3503 set it (this is probably a bug) and if it is set
3504 assign_section_numbers will create a reloc section. */
3505 o->flags &=~ SEC_RELOC;
3506 }
3507
3508 /* If the SEC_ALLOC flag is not set, force the section VMA to
3509 zero. This is done in elf_fake_sections as well, but forcing
3510 the VMA to 0 here will ensure that relocs against these
3511 sections are handled correctly. */
3512 if ((o->flags & SEC_ALLOC) == 0
3513 && ! o->user_set_vma)
3514 o->vma = 0;
3515 }
3516
3517 /* Figure out the file positions for everything but the symbol table
3518 and the relocs. We set symcount to force assign_section_numbers
3519 to create a symbol table. */
3520 abfd->symcount = info->strip == strip_all ? 0 : 1;
3521 BFD_ASSERT (! abfd->output_has_begun);
3522 if (! _bfd_elf_compute_section_file_positions (abfd, info))
3523 goto error_return;
3524
3525 /* That created the reloc sections. Set their sizes, and assign
3526 them file positions, and allocate some buffers. */
3527 for (o = abfd->sections; o != NULL; o = o->next)
3528 {
3529 if ((o->flags & SEC_RELOC) != 0)
3530 {
3531 Elf_Internal_Shdr *rel_hdr;
3532 register struct elf_link_hash_entry **p, **pend;
3533
3534 rel_hdr = &elf_section_data (o)->rel_hdr;
3535
3536 rel_hdr->sh_size = rel_hdr->sh_entsize * o->reloc_count;
3537
3538 /* The contents field must last into write_object_contents,
3539 so we allocate it with bfd_alloc rather than malloc. */
3540 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3541 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3542 goto error_return;
3543
3544 p = ((struct elf_link_hash_entry **)
3545 bfd_malloc (o->reloc_count
3546 * sizeof (struct elf_link_hash_entry *)));
3547 if (p == NULL && o->reloc_count != 0)
3548 goto error_return;
3549 elf_section_data (o)->rel_hashes = p;
3550 pend = p + o->reloc_count;
3551 for (; p < pend; p++)
3552 *p = NULL;
3553
3554 /* Use the reloc_count field as an index when outputting the
3555 relocs. */
3556 o->reloc_count = 0;
3557 }
3558 }
3559
3560 _bfd_elf_assign_file_positions_for_relocs (abfd);
3561
3562 /* We have now assigned file positions for all the sections except
3563 .symtab and .strtab. We start the .symtab section at the current
3564 file position, and write directly to it. We build the .strtab
3565 section in memory. */
3566 abfd->symcount = 0;
3567 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
3568 /* sh_name is set in prep_headers. */
3569 symtab_hdr->sh_type = SHT_SYMTAB;
3570 symtab_hdr->sh_flags = 0;
3571 symtab_hdr->sh_addr = 0;
3572 symtab_hdr->sh_size = 0;
3573 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
3574 /* sh_link is set in assign_section_numbers. */
3575 /* sh_info is set below. */
3576 /* sh_offset is set just below. */
3577 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
3578
3579 off = elf_tdata (abfd)->next_file_pos;
3580 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
3581
3582 /* Note that at this point elf_tdata (abfd)->next_file_pos is
3583 incorrect. We do not yet know the size of the .symtab section.
3584 We correct next_file_pos below, after we do know the size. */
3585
3586 /* Allocate a buffer to hold swapped out symbols. This is to avoid
3587 continuously seeking to the right position in the file. */
3588 if (! info->keep_memory || max_sym_count < 20)
3589 finfo.symbuf_size = 20;
3590 else
3591 finfo.symbuf_size = max_sym_count;
3592 finfo.symbuf = ((Elf_External_Sym *)
3593 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
3594 if (finfo.symbuf == NULL)
3595 goto error_return;
3596
3597 /* Start writing out the symbol table. The first symbol is always a
3598 dummy symbol. */
3599 if (info->strip != strip_all || info->relocateable)
3600 {
3601 elfsym.st_value = 0;
3602 elfsym.st_size = 0;
3603 elfsym.st_info = 0;
3604 elfsym.st_other = 0;
3605 elfsym.st_shndx = SHN_UNDEF;
3606 if (! elf_link_output_sym (&finfo, (const char *) NULL,
3607 &elfsym, bfd_und_section_ptr))
3608 goto error_return;
3609 }
3610
3611 #if 0
3612 /* Some standard ELF linkers do this, but we don't because it causes
3613 bootstrap comparison failures. */
3614 /* Output a file symbol for the output file as the second symbol.
3615 We output this even if we are discarding local symbols, although
3616 I'm not sure if this is correct. */
3617 elfsym.st_value = 0;
3618 elfsym.st_size = 0;
3619 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
3620 elfsym.st_other = 0;
3621 elfsym.st_shndx = SHN_ABS;
3622 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
3623 &elfsym, bfd_abs_section_ptr))
3624 goto error_return;
3625 #endif
3626
3627 /* Output a symbol for each section. We output these even if we are
3628 discarding local symbols, since they are used for relocs. These
3629 symbols have no names. We store the index of each one in the
3630 index field of the section, so that we can find it again when
3631 outputting relocs. */
3632 if (info->strip != strip_all || info->relocateable)
3633 {
3634 elfsym.st_size = 0;
3635 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
3636 elfsym.st_other = 0;
3637 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
3638 {
3639 o = section_from_elf_index (abfd, i);
3640 if (o != NULL)
3641 o->target_index = abfd->symcount;
3642 elfsym.st_shndx = i;
3643 if (info->relocateable || o == NULL)
3644 elfsym.st_value = 0;
3645 else
3646 elfsym.st_value = o->vma;
3647 if (! elf_link_output_sym (&finfo, (const char *) NULL,
3648 &elfsym, o))
3649 goto error_return;
3650 }
3651 }
3652
3653 /* Allocate some memory to hold information read in from the input
3654 files. */
3655 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
3656 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
3657 finfo.internal_relocs = ((Elf_Internal_Rela *)
3658 bfd_malloc (max_internal_reloc_count
3659 * sizeof (Elf_Internal_Rela)));
3660 finfo.external_syms = ((Elf_External_Sym *)
3661 bfd_malloc (max_sym_count
3662 * sizeof (Elf_External_Sym)));
3663 finfo.internal_syms = ((Elf_Internal_Sym *)
3664 bfd_malloc (max_sym_count
3665 * sizeof (Elf_Internal_Sym)));
3666 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
3667 finfo.sections = ((asection **)
3668 bfd_malloc (max_sym_count * sizeof (asection *)));
3669 if ((finfo.contents == NULL && max_contents_size != 0)
3670 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
3671 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
3672 || (finfo.external_syms == NULL && max_sym_count != 0)
3673 || (finfo.internal_syms == NULL && max_sym_count != 0)
3674 || (finfo.indices == NULL && max_sym_count != 0)
3675 || (finfo.sections == NULL && max_sym_count != 0))
3676 goto error_return;
3677
3678 /* Since ELF permits relocations to be against local symbols, we
3679 must have the local symbols available when we do the relocations.
3680 Since we would rather only read the local symbols once, and we
3681 would rather not keep them in memory, we handle all the
3682 relocations for a single input file at the same time.
3683
3684 Unfortunately, there is no way to know the total number of local
3685 symbols until we have seen all of them, and the local symbol
3686 indices precede the global symbol indices. This means that when
3687 we are generating relocateable output, and we see a reloc against
3688 a global symbol, we can not know the symbol index until we have
3689 finished examining all the local symbols to see which ones we are
3690 going to output. To deal with this, we keep the relocations in
3691 memory, and don't output them until the end of the link. This is
3692 an unfortunate waste of memory, but I don't see a good way around
3693 it. Fortunately, it only happens when performing a relocateable
3694 link, which is not the common case. FIXME: If keep_memory is set
3695 we could write the relocs out and then read them again; I don't
3696 know how bad the memory loss will be. */
3697
3698 for (sub = info->input_bfds; sub != NULL; sub = sub->next)
3699 sub->output_has_begun = false;
3700 for (o = abfd->sections; o != NULL; o = o->next)
3701 {
3702 for (p = o->link_order_head; p != NULL; p = p->next)
3703 {
3704 if (p->type == bfd_indirect_link_order
3705 && (bfd_get_flavour (p->u.indirect.section->owner)
3706 == bfd_target_elf_flavour))
3707 {
3708 sub = p->u.indirect.section->owner;
3709 if (! sub->output_has_begun)
3710 {
3711 if (! elf_link_input_bfd (&finfo, sub))
3712 goto error_return;
3713 sub->output_has_begun = true;
3714 }
3715 }
3716 else if (p->type == bfd_section_reloc_link_order
3717 || p->type == bfd_symbol_reloc_link_order)
3718 {
3719 if (! elf_reloc_link_order (abfd, info, o, p))
3720 goto error_return;
3721 }
3722 else
3723 {
3724 if (! _bfd_default_link_order (abfd, info, o, p))
3725 goto error_return;
3726 }
3727 }
3728 }
3729
3730 /* That wrote out all the local symbols. Finish up the symbol table
3731 with the global symbols. */
3732
3733 if (info->strip != strip_all && info->shared)
3734 {
3735 /* Output any global symbols that got converted to local in a
3736 version script. We do this in a separate step since ELF
3737 requires all local symbols to appear prior to any global
3738 symbols. FIXME: We should only do this if some global
3739 symbols were, in fact, converted to become local. FIXME:
3740 Will this work correctly with the Irix 5 linker? */
3741 eoinfo.failed = false;
3742 eoinfo.finfo = &finfo;
3743 eoinfo.localsyms = true;
3744 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
3745 (PTR) &eoinfo);
3746 if (eoinfo.failed)
3747 return false;
3748 }
3749
3750 /* The sh_info field records the index of the first non local
3751 symbol. */
3752 symtab_hdr->sh_info = abfd->symcount;
3753 if (dynamic)
3754 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info = 1;
3755
3756 /* We get the global symbols from the hash table. */
3757 eoinfo.failed = false;
3758 eoinfo.localsyms = false;
3759 eoinfo.finfo = &finfo;
3760 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
3761 (PTR) &eoinfo);
3762 if (eoinfo.failed)
3763 return false;
3764
3765 /* Flush all symbols to the file. */
3766 if (! elf_link_flush_output_syms (&finfo))
3767 return false;
3768
3769 /* Now we know the size of the symtab section. */
3770 off += symtab_hdr->sh_size;
3771
3772 /* Finish up and write out the symbol string table (.strtab)
3773 section. */
3774 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
3775 /* sh_name was set in prep_headers. */
3776 symstrtab_hdr->sh_type = SHT_STRTAB;
3777 symstrtab_hdr->sh_flags = 0;
3778 symstrtab_hdr->sh_addr = 0;
3779 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
3780 symstrtab_hdr->sh_entsize = 0;
3781 symstrtab_hdr->sh_link = 0;
3782 symstrtab_hdr->sh_info = 0;
3783 /* sh_offset is set just below. */
3784 symstrtab_hdr->sh_addralign = 1;
3785
3786 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
3787 elf_tdata (abfd)->next_file_pos = off;
3788
3789 if (abfd->symcount > 0)
3790 {
3791 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
3792 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
3793 return false;
3794 }
3795
3796 /* Adjust the relocs to have the correct symbol indices. */
3797 for (o = abfd->sections; o != NULL; o = o->next)
3798 {
3799 struct elf_link_hash_entry **rel_hash;
3800 Elf_Internal_Shdr *rel_hdr;
3801
3802 if ((o->flags & SEC_RELOC) == 0)
3803 continue;
3804
3805 rel_hash = elf_section_data (o)->rel_hashes;
3806 rel_hdr = &elf_section_data (o)->rel_hdr;
3807 for (i = 0; i < o->reloc_count; i++, rel_hash++)
3808 {
3809 if (*rel_hash == NULL)
3810 continue;
3811
3812 BFD_ASSERT ((*rel_hash)->indx >= 0);
3813
3814 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3815 {
3816 Elf_External_Rel *erel;
3817 Elf_Internal_Rel irel;
3818
3819 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3820 elf_swap_reloc_in (abfd, erel, &irel);
3821 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3822 ELF_R_TYPE (irel.r_info));
3823 elf_swap_reloc_out (abfd, &irel, erel);
3824 }
3825 else
3826 {
3827 Elf_External_Rela *erela;
3828 Elf_Internal_Rela irela;
3829
3830 BFD_ASSERT (rel_hdr->sh_entsize
3831 == sizeof (Elf_External_Rela));
3832
3833 erela = (Elf_External_Rela *) rel_hdr->contents + i;
3834 elf_swap_reloca_in (abfd, erela, &irela);
3835 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
3836 ELF_R_TYPE (irela.r_info));
3837 elf_swap_reloca_out (abfd, &irela, erela);
3838 }
3839 }
3840
3841 /* Set the reloc_count field to 0 to prevent write_relocs from
3842 trying to swap the relocs out itself. */
3843 o->reloc_count = 0;
3844 }
3845
3846 /* If we are linking against a dynamic object, or generating a
3847 shared library, finish up the dynamic linking information. */
3848 if (dynamic)
3849 {
3850 Elf_External_Dyn *dyncon, *dynconend;
3851
3852 /* Fix up .dynamic entries. */
3853 o = bfd_get_section_by_name (dynobj, ".dynamic");
3854 BFD_ASSERT (o != NULL);
3855
3856 dyncon = (Elf_External_Dyn *) o->contents;
3857 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
3858 for (; dyncon < dynconend; dyncon++)
3859 {
3860 Elf_Internal_Dyn dyn;
3861 const char *name;
3862 unsigned int type;
3863
3864 elf_swap_dyn_in (dynobj, dyncon, &dyn);
3865
3866 switch (dyn.d_tag)
3867 {
3868 default:
3869 break;
3870
3871 /* SVR4 linkers seem to set DT_INIT and DT_FINI based on
3872 magic _init and _fini symbols. This is pretty ugly,
3873 but we are compatible. */
3874 case DT_INIT:
3875 name = "_init";
3876 goto get_sym;
3877 case DT_FINI:
3878 name = "_fini";
3879 get_sym:
3880 {
3881 struct elf_link_hash_entry *h;
3882
3883 h = elf_link_hash_lookup (elf_hash_table (info), name,
3884 false, false, true);
3885 if (h != NULL
3886 && (h->root.type == bfd_link_hash_defined
3887 || h->root.type == bfd_link_hash_defweak))
3888 {
3889 dyn.d_un.d_val = h->root.u.def.value;
3890 o = h->root.u.def.section;
3891 if (o->output_section != NULL)
3892 dyn.d_un.d_val += (o->output_section->vma
3893 + o->output_offset);
3894 else
3895 {
3896 /* The symbol is imported from another shared
3897 library and does not apply to this one. */
3898 dyn.d_un.d_val = 0;
3899 }
3900
3901 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3902 }
3903 }
3904 break;
3905
3906 case DT_HASH:
3907 name = ".hash";
3908 goto get_vma;
3909 case DT_STRTAB:
3910 name = ".dynstr";
3911 goto get_vma;
3912 case DT_SYMTAB:
3913 name = ".dynsym";
3914 goto get_vma;
3915 case DT_VERDEF:
3916 name = ".gnu.version_d";
3917 goto get_vma;
3918 case DT_VERNEED:
3919 name = ".gnu.version_r";
3920 goto get_vma;
3921 case DT_VERSYM:
3922 name = ".gnu.version";
3923 get_vma:
3924 o = bfd_get_section_by_name (abfd, name);
3925 BFD_ASSERT (o != NULL);
3926 dyn.d_un.d_ptr = o->vma;
3927 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3928 break;
3929
3930 case DT_REL:
3931 case DT_RELA:
3932 case DT_RELSZ:
3933 case DT_RELASZ:
3934 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
3935 type = SHT_REL;
3936 else
3937 type = SHT_RELA;
3938 dyn.d_un.d_val = 0;
3939 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
3940 {
3941 Elf_Internal_Shdr *hdr;
3942
3943 hdr = elf_elfsections (abfd)[i];
3944 if (hdr->sh_type == type
3945 && (hdr->sh_flags & SHF_ALLOC) != 0)
3946 {
3947 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
3948 dyn.d_un.d_val += hdr->sh_size;
3949 else
3950 {
3951 if (dyn.d_un.d_val == 0
3952 || hdr->sh_addr < dyn.d_un.d_val)
3953 dyn.d_un.d_val = hdr->sh_addr;
3954 }
3955 }
3956 }
3957 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3958 break;
3959 }
3960 }
3961 }
3962
3963 /* If we have created any dynamic sections, then output them. */
3964 if (dynobj != NULL)
3965 {
3966 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
3967 goto error_return;
3968
3969 for (o = dynobj->sections; o != NULL; o = o->next)
3970 {
3971 if ((o->flags & SEC_HAS_CONTENTS) == 0
3972 || o->_raw_size == 0)
3973 continue;
3974 if ((o->flags & SEC_LINKER_CREATED) == 0)
3975 {
3976 /* At this point, we are only interested in sections
3977 created by elf_link_create_dynamic_sections. */
3978 continue;
3979 }
3980 if ((elf_section_data (o->output_section)->this_hdr.sh_type
3981 != SHT_STRTAB)
3982 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
3983 {
3984 if (! bfd_set_section_contents (abfd, o->output_section,
3985 o->contents, o->output_offset,
3986 o->_raw_size))
3987 goto error_return;
3988 }
3989 else
3990 {
3991 file_ptr off;
3992
3993 /* The contents of the .dynstr section are actually in a
3994 stringtab. */
3995 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
3996 if (bfd_seek (abfd, off, SEEK_SET) != 0
3997 || ! _bfd_stringtab_emit (abfd,
3998 elf_hash_table (info)->dynstr))
3999 goto error_return;
4000 }
4001 }
4002 }
4003
4004 /* If we have optimized stabs strings, output them. */
4005 if (elf_hash_table (info)->stab_info != NULL)
4006 {
4007 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4008 goto error_return;
4009 }
4010
4011 if (finfo.symstrtab != NULL)
4012 _bfd_stringtab_free (finfo.symstrtab);
4013 if (finfo.contents != NULL)
4014 free (finfo.contents);
4015 if (finfo.external_relocs != NULL)
4016 free (finfo.external_relocs);
4017 if (finfo.internal_relocs != NULL)
4018 free (finfo.internal_relocs);
4019 if (finfo.external_syms != NULL)
4020 free (finfo.external_syms);
4021 if (finfo.internal_syms != NULL)
4022 free (finfo.internal_syms);
4023 if (finfo.indices != NULL)
4024 free (finfo.indices);
4025 if (finfo.sections != NULL)
4026 free (finfo.sections);
4027 if (finfo.symbuf != NULL)
4028 free (finfo.symbuf);
4029 for (o = abfd->sections; o != NULL; o = o->next)
4030 {
4031 if ((o->flags & SEC_RELOC) != 0
4032 && elf_section_data (o)->rel_hashes != NULL)
4033 free (elf_section_data (o)->rel_hashes);
4034 }
4035
4036 elf_tdata (abfd)->linker = true;
4037
4038 return true;
4039
4040 error_return:
4041 if (finfo.symstrtab != NULL)
4042 _bfd_stringtab_free (finfo.symstrtab);
4043 if (finfo.contents != NULL)
4044 free (finfo.contents);
4045 if (finfo.external_relocs != NULL)
4046 free (finfo.external_relocs);
4047 if (finfo.internal_relocs != NULL)
4048 free (finfo.internal_relocs);
4049 if (finfo.external_syms != NULL)
4050 free (finfo.external_syms);
4051 if (finfo.internal_syms != NULL)
4052 free (finfo.internal_syms);
4053 if (finfo.indices != NULL)
4054 free (finfo.indices);
4055 if (finfo.sections != NULL)
4056 free (finfo.sections);
4057 if (finfo.symbuf != NULL)
4058 free (finfo.symbuf);
4059 for (o = abfd->sections; o != NULL; o = o->next)
4060 {
4061 if ((o->flags & SEC_RELOC) != 0
4062 && elf_section_data (o)->rel_hashes != NULL)
4063 free (elf_section_data (o)->rel_hashes);
4064 }
4065
4066 return false;
4067 }
4068
4069 /* Add a symbol to the output symbol table. */
4070
4071 static boolean
4072 elf_link_output_sym (finfo, name, elfsym, input_sec)
4073 struct elf_final_link_info *finfo;
4074 const char *name;
4075 Elf_Internal_Sym *elfsym;
4076 asection *input_sec;
4077 {
4078 boolean (*output_symbol_hook) PARAMS ((bfd *,
4079 struct bfd_link_info *info,
4080 const char *,
4081 Elf_Internal_Sym *,
4082 asection *));
4083
4084 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4085 elf_backend_link_output_symbol_hook;
4086 if (output_symbol_hook != NULL)
4087 {
4088 if (! ((*output_symbol_hook)
4089 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4090 return false;
4091 }
4092
4093 if (name == (const char *) NULL || *name == '\0')
4094 elfsym->st_name = 0;
4095 else
4096 {
4097 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4098 name, true,
4099 false);
4100 if (elfsym->st_name == (unsigned long) -1)
4101 return false;
4102 }
4103
4104 if (finfo->symbuf_count >= finfo->symbuf_size)
4105 {
4106 if (! elf_link_flush_output_syms (finfo))
4107 return false;
4108 }
4109
4110 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4111 (PTR) (finfo->symbuf + finfo->symbuf_count));
4112 ++finfo->symbuf_count;
4113
4114 ++finfo->output_bfd->symcount;
4115
4116 return true;
4117 }
4118
4119 /* Flush the output symbols to the file. */
4120
4121 static boolean
4122 elf_link_flush_output_syms (finfo)
4123 struct elf_final_link_info *finfo;
4124 {
4125 if (finfo->symbuf_count > 0)
4126 {
4127 Elf_Internal_Shdr *symtab;
4128
4129 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4130
4131 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4132 SEEK_SET) != 0
4133 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4134 sizeof (Elf_External_Sym), finfo->output_bfd)
4135 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4136 return false;
4137
4138 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4139
4140 finfo->symbuf_count = 0;
4141 }
4142
4143 return true;
4144 }
4145
4146 /* Add an external symbol to the symbol table. This is called from
4147 the hash table traversal routine. When generating a shared object,
4148 we go through the symbol table twice. The first time we output
4149 anything that might have been forced to local scope in a version
4150 script. The second time we output the symbols that are still
4151 global symbols. */
4152
4153 static boolean
4154 elf_link_output_extsym (h, data)
4155 struct elf_link_hash_entry *h;
4156 PTR data;
4157 {
4158 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4159 struct elf_final_link_info *finfo = eoinfo->finfo;
4160 boolean strip;
4161 Elf_Internal_Sym sym;
4162 asection *input_sec;
4163
4164 /* Decide whether to output this symbol in this pass. */
4165 if (eoinfo->localsyms)
4166 {
4167 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4168 return true;
4169 }
4170 else
4171 {
4172 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4173 return true;
4174 }
4175
4176 /* If we are not creating a shared library, and this symbol is
4177 referenced by a shared library but is not defined anywhere, then
4178 warn that it is undefined. If we do not do this, the runtime
4179 linker will complain that the symbol is undefined when the
4180 program is run. We don't have to worry about symbols that are
4181 referenced by regular files, because we will already have issued
4182 warnings for them. */
4183 if (! finfo->info->relocateable
4184 && ! finfo->info->shared
4185 && h->root.type == bfd_link_hash_undefined
4186 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4187 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4188 {
4189 if (! ((*finfo->info->callbacks->undefined_symbol)
4190 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4191 (asection *) NULL, 0)))
4192 {
4193 eoinfo->failed = true;
4194 return false;
4195 }
4196 }
4197
4198 /* We don't want to output symbols that have never been mentioned by
4199 a regular file, or that we have been told to strip. However, if
4200 h->indx is set to -2, the symbol is used by a reloc and we must
4201 output it. */
4202 if (h->indx == -2)
4203 strip = false;
4204 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4205 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4206 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4207 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4208 strip = true;
4209 else if (finfo->info->strip == strip_all
4210 || (finfo->info->strip == strip_some
4211 && bfd_hash_lookup (finfo->info->keep_hash,
4212 h->root.root.string,
4213 false, false) == NULL))
4214 strip = true;
4215 else
4216 strip = false;
4217
4218 /* If we're stripping it, and it's not a dynamic symbol, there's
4219 nothing else to do. */
4220 if (strip && h->dynindx == -1)
4221 return true;
4222
4223 sym.st_value = 0;
4224 sym.st_size = h->size;
4225 sym.st_other = h->other;
4226 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4227 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4228 else if (h->root.type == bfd_link_hash_undefweak
4229 || h->root.type == bfd_link_hash_defweak)
4230 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4231 else
4232 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4233
4234 switch (h->root.type)
4235 {
4236 default:
4237 case bfd_link_hash_new:
4238 abort ();
4239 return false;
4240
4241 case bfd_link_hash_undefined:
4242 input_sec = bfd_und_section_ptr;
4243 sym.st_shndx = SHN_UNDEF;
4244 break;
4245
4246 case bfd_link_hash_undefweak:
4247 input_sec = bfd_und_section_ptr;
4248 sym.st_shndx = SHN_UNDEF;
4249 break;
4250
4251 case bfd_link_hash_defined:
4252 case bfd_link_hash_defweak:
4253 {
4254 input_sec = h->root.u.def.section;
4255 if (input_sec->output_section != NULL)
4256 {
4257 sym.st_shndx =
4258 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4259 input_sec->output_section);
4260 if (sym.st_shndx == (unsigned short) -1)
4261 {
4262 eoinfo->failed = true;
4263 return false;
4264 }
4265
4266 /* ELF symbols in relocateable files are section relative,
4267 but in nonrelocateable files they are virtual
4268 addresses. */
4269 sym.st_value = h->root.u.def.value + input_sec->output_offset;
4270 if (! finfo->info->relocateable)
4271 sym.st_value += input_sec->output_section->vma;
4272 }
4273 else
4274 {
4275 BFD_ASSERT (input_sec->owner == NULL
4276 || (input_sec->owner->flags & DYNAMIC) != 0);
4277 sym.st_shndx = SHN_UNDEF;
4278 input_sec = bfd_und_section_ptr;
4279 }
4280 }
4281 break;
4282
4283 case bfd_link_hash_common:
4284 input_sec = h->root.u.c.p->section;
4285 sym.st_shndx = SHN_COMMON;
4286 sym.st_value = 1 << h->root.u.c.p->alignment_power;
4287 break;
4288
4289 case bfd_link_hash_indirect:
4290 /* These symbols are created by symbol versioning. They point
4291 to the decorated version of the name. For example, if the
4292 symbol foo@@GNU_1.2 is the default, which should be used when
4293 foo is used with no version, then we add an indirect symbol
4294 foo which points to foo@@GNU_1.2. We ignore these symbols,
4295 since the indirected symbol is already in the hash table. If
4296 the indirect symbol is non-ELF, fall through and output it. */
4297 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
4298 return true;
4299
4300 /* Fall through. */
4301 case bfd_link_hash_warning:
4302 /* We can't represent these symbols in ELF, although a warning
4303 symbol may have come from a .gnu.warning.SYMBOL section. We
4304 just put the target symbol in the hash table. If the target
4305 symbol does not really exist, don't do anything. */
4306 if (h->root.u.i.link->type == bfd_link_hash_new)
4307 return true;
4308 return (elf_link_output_extsym
4309 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
4310 }
4311
4312 /* Give the processor backend a chance to tweak the symbol value,
4313 and also to finish up anything that needs to be done for this
4314 symbol. */
4315 if ((h->dynindx != -1
4316 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4317 && elf_hash_table (finfo->info)->dynamic_sections_created)
4318 {
4319 struct elf_backend_data *bed;
4320
4321 bed = get_elf_backend_data (finfo->output_bfd);
4322 if (! ((*bed->elf_backend_finish_dynamic_symbol)
4323 (finfo->output_bfd, finfo->info, h, &sym)))
4324 {
4325 eoinfo->failed = true;
4326 return false;
4327 }
4328 }
4329
4330 /* If this symbol should be put in the .dynsym section, then put it
4331 there now. We have already know the symbol index. We also fill
4332 in the entry in the .hash section. */
4333 if (h->dynindx != -1
4334 && elf_hash_table (finfo->info)->dynamic_sections_created)
4335 {
4336 char *p, *copy;
4337 const char *name;
4338 size_t bucketcount;
4339 size_t bucket;
4340 bfd_byte *bucketpos;
4341 bfd_vma chain;
4342
4343 sym.st_name = h->dynstr_index;
4344
4345 elf_swap_symbol_out (finfo->output_bfd, &sym,
4346 (PTR) (((Elf_External_Sym *)
4347 finfo->dynsym_sec->contents)
4348 + h->dynindx));
4349
4350 /* We didn't include the version string in the dynamic string
4351 table, so we must not consider it in the hash table. */
4352 name = h->root.root.string;
4353 p = strchr (name, ELF_VER_CHR);
4354 if (p == NULL)
4355 copy = NULL;
4356 else
4357 {
4358 copy = bfd_alloc (finfo->output_bfd, p - name + 1);
4359 strncpy (copy, name, p - name);
4360 copy[p - name] = '\0';
4361 name = copy;
4362 }
4363
4364 bucketcount = elf_hash_table (finfo->info)->bucketcount;
4365 bucket = bfd_elf_hash ((const unsigned char *) name) % bucketcount;
4366 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
4367 + (bucket + 2) * (ARCH_SIZE / 8));
4368 chain = get_word (finfo->output_bfd, bucketpos);
4369 put_word (finfo->output_bfd, h->dynindx, bucketpos);
4370 put_word (finfo->output_bfd, chain,
4371 ((bfd_byte *) finfo->hash_sec->contents
4372 + (bucketcount + 2 + h->dynindx) * (ARCH_SIZE / 8)));
4373
4374 if (copy != NULL)
4375 bfd_release (finfo->output_bfd, copy);
4376
4377 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
4378 {
4379 Elf_Internal_Versym iversym;
4380
4381 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
4382 {
4383 if (h->verinfo.verdef == NULL)
4384 iversym.vs_vers = 0;
4385 else
4386 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
4387 }
4388 else
4389 {
4390 if (h->verinfo.vertree == NULL)
4391 iversym.vs_vers = 1;
4392 else
4393 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
4394 }
4395
4396 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
4397 iversym.vs_vers |= VERSYM_HIDDEN;
4398
4399 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
4400 (((Elf_External_Versym *)
4401 finfo->symver_sec->contents)
4402 + h->dynindx));
4403 }
4404 }
4405
4406 /* If we're stripping it, then it was just a dynamic symbol, and
4407 there's nothing else to do. */
4408 if (strip)
4409 return true;
4410
4411 h->indx = finfo->output_bfd->symcount;
4412
4413 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
4414 {
4415 eoinfo->failed = true;
4416 return false;
4417 }
4418
4419 return true;
4420 }
4421
4422 /* Link an input file into the linker output file. This function
4423 handles all the sections and relocations of the input file at once.
4424 This is so that we only have to read the local symbols once, and
4425 don't have to keep them in memory. */
4426
4427 static boolean
4428 elf_link_input_bfd (finfo, input_bfd)
4429 struct elf_final_link_info *finfo;
4430 bfd *input_bfd;
4431 {
4432 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
4433 bfd *, asection *, bfd_byte *,
4434 Elf_Internal_Rela *,
4435 Elf_Internal_Sym *, asection **));
4436 bfd *output_bfd;
4437 Elf_Internal_Shdr *symtab_hdr;
4438 size_t locsymcount;
4439 size_t extsymoff;
4440 Elf_External_Sym *external_syms;
4441 Elf_External_Sym *esym;
4442 Elf_External_Sym *esymend;
4443 Elf_Internal_Sym *isym;
4444 long *pindex;
4445 asection **ppsection;
4446 asection *o;
4447
4448 output_bfd = finfo->output_bfd;
4449 relocate_section =
4450 get_elf_backend_data (output_bfd)->elf_backend_relocate_section;
4451
4452 /* If this is a dynamic object, we don't want to do anything here:
4453 we don't want the local symbols, and we don't want the section
4454 contents. */
4455 if ((input_bfd->flags & DYNAMIC) != 0)
4456 return true;
4457
4458 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
4459 if (elf_bad_symtab (input_bfd))
4460 {
4461 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
4462 extsymoff = 0;
4463 }
4464 else
4465 {
4466 locsymcount = symtab_hdr->sh_info;
4467 extsymoff = symtab_hdr->sh_info;
4468 }
4469
4470 /* Read the local symbols. */
4471 if (symtab_hdr->contents != NULL)
4472 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
4473 else if (locsymcount == 0)
4474 external_syms = NULL;
4475 else
4476 {
4477 external_syms = finfo->external_syms;
4478 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
4479 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
4480 locsymcount, input_bfd)
4481 != locsymcount * sizeof (Elf_External_Sym)))
4482 return false;
4483 }
4484
4485 /* Swap in the local symbols and write out the ones which we know
4486 are going into the output file. */
4487 esym = external_syms;
4488 esymend = esym + locsymcount;
4489 isym = finfo->internal_syms;
4490 pindex = finfo->indices;
4491 ppsection = finfo->sections;
4492 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
4493 {
4494 asection *isec;
4495 const char *name;
4496 Elf_Internal_Sym osym;
4497
4498 elf_swap_symbol_in (input_bfd, esym, isym);
4499 *pindex = -1;
4500
4501 if (elf_bad_symtab (input_bfd))
4502 {
4503 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
4504 {
4505 *ppsection = NULL;
4506 continue;
4507 }
4508 }
4509
4510 if (isym->st_shndx == SHN_UNDEF)
4511 isec = bfd_und_section_ptr;
4512 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
4513 isec = section_from_elf_index (input_bfd, isym->st_shndx);
4514 else if (isym->st_shndx == SHN_ABS)
4515 isec = bfd_abs_section_ptr;
4516 else if (isym->st_shndx == SHN_COMMON)
4517 isec = bfd_com_section_ptr;
4518 else
4519 {
4520 /* Who knows? */
4521 isec = NULL;
4522 }
4523
4524 *ppsection = isec;
4525
4526 /* Don't output the first, undefined, symbol. */
4527 if (esym == external_syms)
4528 continue;
4529
4530 /* If we are stripping all symbols, we don't want to output this
4531 one. */
4532 if (finfo->info->strip == strip_all)
4533 continue;
4534
4535 /* We never output section symbols. Instead, we use the section
4536 symbol of the corresponding section in the output file. */
4537 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
4538 continue;
4539
4540 /* If we are discarding all local symbols, we don't want to
4541 output this one. If we are generating a relocateable output
4542 file, then some of the local symbols may be required by
4543 relocs; we output them below as we discover that they are
4544 needed. */
4545 if (finfo->info->discard == discard_all)
4546 continue;
4547
4548 /* If this symbol is defined in a section which we are
4549 discarding, we don't need to keep it, but note that
4550 linker_mark is only reliable for sections that have contents.
4551 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
4552 as well as linker_mark. */
4553 if (isym->st_shndx > 0
4554 && isym->st_shndx < SHN_LORESERVE
4555 && isec != NULL
4556 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
4557 || (! finfo->info->relocateable
4558 && (isec->flags & SEC_EXCLUDE) != 0)))
4559 continue;
4560
4561 /* Get the name of the symbol. */
4562 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
4563 isym->st_name);
4564 if (name == NULL)
4565 return false;
4566
4567 /* See if we are discarding symbols with this name. */
4568 if ((finfo->info->strip == strip_some
4569 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
4570 == NULL))
4571 || (finfo->info->discard == discard_l
4572 && bfd_is_local_label_name (input_bfd, name)))
4573 continue;
4574
4575 /* If we get here, we are going to output this symbol. */
4576
4577 osym = *isym;
4578
4579 /* Adjust the section index for the output file. */
4580 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
4581 isec->output_section);
4582 if (osym.st_shndx == (unsigned short) -1)
4583 return false;
4584
4585 *pindex = output_bfd->symcount;
4586
4587 /* ELF symbols in relocateable files are section relative, but
4588 in executable files they are virtual addresses. Note that
4589 this code assumes that all ELF sections have an associated
4590 BFD section with a reasonable value for output_offset; below
4591 we assume that they also have a reasonable value for
4592 output_section. Any special sections must be set up to meet
4593 these requirements. */
4594 osym.st_value += isec->output_offset;
4595 if (! finfo->info->relocateable)
4596 osym.st_value += isec->output_section->vma;
4597
4598 if (! elf_link_output_sym (finfo, name, &osym, isec))
4599 return false;
4600 }
4601
4602 /* Relocate the contents of each section. */
4603 for (o = input_bfd->sections; o != NULL; o = o->next)
4604 {
4605 bfd_byte *contents;
4606
4607 if (! o->linker_mark)
4608 {
4609 /* This section was omitted from the link. */
4610 continue;
4611 }
4612
4613 if ((o->flags & SEC_HAS_CONTENTS) == 0
4614 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
4615 continue;
4616
4617 if ((o->flags & SEC_LINKER_CREATED) != 0)
4618 {
4619 /* Section was created by elf_link_create_dynamic_sections
4620 or somesuch. */
4621 continue;
4622 }
4623
4624 /* Get the contents of the section. They have been cached by a
4625 relaxation routine. Note that o is a section in an input
4626 file, so the contents field will not have been set by any of
4627 the routines which work on output files. */
4628 if (elf_section_data (o)->this_hdr.contents != NULL)
4629 contents = elf_section_data (o)->this_hdr.contents;
4630 else
4631 {
4632 contents = finfo->contents;
4633 if (! bfd_get_section_contents (input_bfd, o, contents,
4634 (file_ptr) 0, o->_raw_size))
4635 return false;
4636 }
4637
4638 if ((o->flags & SEC_RELOC) != 0)
4639 {
4640 Elf_Internal_Rela *internal_relocs;
4641
4642 /* Get the swapped relocs. */
4643 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
4644 (input_bfd, o, finfo->external_relocs,
4645 finfo->internal_relocs, false));
4646 if (internal_relocs == NULL
4647 && o->reloc_count > 0)
4648 return false;
4649
4650 /* Relocate the section by invoking a back end routine.
4651
4652 The back end routine is responsible for adjusting the
4653 section contents as necessary, and (if using Rela relocs
4654 and generating a relocateable output file) adjusting the
4655 reloc addend as necessary.
4656
4657 The back end routine does not have to worry about setting
4658 the reloc address or the reloc symbol index.
4659
4660 The back end routine is given a pointer to the swapped in
4661 internal symbols, and can access the hash table entries
4662 for the external symbols via elf_sym_hashes (input_bfd).
4663
4664 When generating relocateable output, the back end routine
4665 must handle STB_LOCAL/STT_SECTION symbols specially. The
4666 output symbol is going to be a section symbol
4667 corresponding to the output section, which will require
4668 the addend to be adjusted. */
4669
4670 if (! (*relocate_section) (output_bfd, finfo->info,
4671 input_bfd, o, contents,
4672 internal_relocs,
4673 finfo->internal_syms,
4674 finfo->sections))
4675 return false;
4676
4677 if (finfo->info->relocateable)
4678 {
4679 Elf_Internal_Rela *irela;
4680 Elf_Internal_Rela *irelaend;
4681 struct elf_link_hash_entry **rel_hash;
4682 Elf_Internal_Shdr *input_rel_hdr;
4683 Elf_Internal_Shdr *output_rel_hdr;
4684
4685 /* Adjust the reloc addresses and symbol indices. */
4686
4687 irela = internal_relocs;
4688 irelaend = irela + o->reloc_count;
4689 rel_hash = (elf_section_data (o->output_section)->rel_hashes
4690 + o->output_section->reloc_count);
4691 for (; irela < irelaend; irela++, rel_hash++)
4692 {
4693 unsigned long r_symndx;
4694 Elf_Internal_Sym *isym;
4695 asection *sec;
4696
4697 irela->r_offset += o->output_offset;
4698
4699 r_symndx = ELF_R_SYM (irela->r_info);
4700
4701 if (r_symndx == 0)
4702 continue;
4703
4704 if (r_symndx >= locsymcount
4705 || (elf_bad_symtab (input_bfd)
4706 && finfo->sections[r_symndx] == NULL))
4707 {
4708 long indx;
4709
4710 /* This is a reloc against a global symbol. We
4711 have not yet output all the local symbols, so
4712 we do not know the symbol index of any global
4713 symbol. We set the rel_hash entry for this
4714 reloc to point to the global hash table entry
4715 for this symbol. The symbol index is then
4716 set at the end of elf_bfd_final_link. */
4717 indx = r_symndx - extsymoff;
4718 *rel_hash = elf_sym_hashes (input_bfd)[indx];
4719
4720 /* Setting the index to -2 tells
4721 elf_link_output_extsym that this symbol is
4722 used by a reloc. */
4723 BFD_ASSERT ((*rel_hash)->indx < 0);
4724 (*rel_hash)->indx = -2;
4725
4726 continue;
4727 }
4728
4729 /* This is a reloc against a local symbol. */
4730
4731 *rel_hash = NULL;
4732 isym = finfo->internal_syms + r_symndx;
4733 sec = finfo->sections[r_symndx];
4734 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
4735 {
4736 /* I suppose the backend ought to fill in the
4737 section of any STT_SECTION symbol against a
4738 processor specific section. If we have
4739 discarded a section, the output_section will
4740 be the absolute section. */
4741 if (sec != NULL
4742 && (bfd_is_abs_section (sec)
4743 || (sec->output_section != NULL
4744 && bfd_is_abs_section (sec->output_section))))
4745 r_symndx = 0;
4746 else if (sec == NULL || sec->owner == NULL)
4747 {
4748 bfd_set_error (bfd_error_bad_value);
4749 return false;
4750 }
4751 else
4752 {
4753 r_symndx = sec->output_section->target_index;
4754 BFD_ASSERT (r_symndx != 0);
4755 }
4756 }
4757 else
4758 {
4759 if (finfo->indices[r_symndx] == -1)
4760 {
4761 unsigned long link;
4762 const char *name;
4763 asection *osec;
4764
4765 if (finfo->info->strip == strip_all)
4766 {
4767 /* You can't do ld -r -s. */
4768 bfd_set_error (bfd_error_invalid_operation);
4769 return false;
4770 }
4771
4772 /* This symbol was skipped earlier, but
4773 since it is needed by a reloc, we
4774 must output it now. */
4775 link = symtab_hdr->sh_link;
4776 name = bfd_elf_string_from_elf_section (input_bfd,
4777 link,
4778 isym->st_name);
4779 if (name == NULL)
4780 return false;
4781
4782 osec = sec->output_section;
4783 isym->st_shndx =
4784 _bfd_elf_section_from_bfd_section (output_bfd,
4785 osec);
4786 if (isym->st_shndx == (unsigned short) -1)
4787 return false;
4788
4789 isym->st_value += sec->output_offset;
4790 if (! finfo->info->relocateable)
4791 isym->st_value += osec->vma;
4792
4793 finfo->indices[r_symndx] = output_bfd->symcount;
4794
4795 if (! elf_link_output_sym (finfo, name, isym, sec))
4796 return false;
4797 }
4798
4799 r_symndx = finfo->indices[r_symndx];
4800 }
4801
4802 irela->r_info = ELF_R_INFO (r_symndx,
4803 ELF_R_TYPE (irela->r_info));
4804 }
4805
4806 /* Swap out the relocs. */
4807 input_rel_hdr = &elf_section_data (o)->rel_hdr;
4808 output_rel_hdr = &elf_section_data (o->output_section)->rel_hdr;
4809 BFD_ASSERT (output_rel_hdr->sh_entsize
4810 == input_rel_hdr->sh_entsize);
4811 irela = internal_relocs;
4812 irelaend = irela + o->reloc_count;
4813 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4814 {
4815 Elf_External_Rel *erel;
4816
4817 erel = ((Elf_External_Rel *) output_rel_hdr->contents
4818 + o->output_section->reloc_count);
4819 for (; irela < irelaend; irela++, erel++)
4820 {
4821 Elf_Internal_Rel irel;
4822
4823 irel.r_offset = irela->r_offset;
4824 irel.r_info = irela->r_info;
4825 BFD_ASSERT (irela->r_addend == 0);
4826 elf_swap_reloc_out (output_bfd, &irel, erel);
4827 }
4828 }
4829 else
4830 {
4831 Elf_External_Rela *erela;
4832
4833 BFD_ASSERT (input_rel_hdr->sh_entsize
4834 == sizeof (Elf_External_Rela));
4835 erela = ((Elf_External_Rela *) output_rel_hdr->contents
4836 + o->output_section->reloc_count);
4837 for (; irela < irelaend; irela++, erela++)
4838 elf_swap_reloca_out (output_bfd, irela, erela);
4839 }
4840
4841 o->output_section->reloc_count += o->reloc_count;
4842 }
4843 }
4844
4845 /* Write out the modified section contents. */
4846 if (elf_section_data (o)->stab_info == NULL)
4847 {
4848 if (! bfd_set_section_contents (output_bfd, o->output_section,
4849 contents, o->output_offset,
4850 (o->_cooked_size != 0
4851 ? o->_cooked_size
4852 : o->_raw_size)))
4853 return false;
4854 }
4855 else
4856 {
4857 if (! (_bfd_write_section_stabs
4858 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
4859 o, &elf_section_data (o)->stab_info, contents)))
4860 return false;
4861 }
4862 }
4863
4864 return true;
4865 }
4866
4867 /* Generate a reloc when linking an ELF file. This is a reloc
4868 requested by the linker, and does come from any input file. This
4869 is used to build constructor and destructor tables when linking
4870 with -Ur. */
4871
4872 static boolean
4873 elf_reloc_link_order (output_bfd, info, output_section, link_order)
4874 bfd *output_bfd;
4875 struct bfd_link_info *info;
4876 asection *output_section;
4877 struct bfd_link_order *link_order;
4878 {
4879 reloc_howto_type *howto;
4880 long indx;
4881 bfd_vma offset;
4882 bfd_vma addend;
4883 struct elf_link_hash_entry **rel_hash_ptr;
4884 Elf_Internal_Shdr *rel_hdr;
4885
4886 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
4887 if (howto == NULL)
4888 {
4889 bfd_set_error (bfd_error_bad_value);
4890 return false;
4891 }
4892
4893 addend = link_order->u.reloc.p->addend;
4894
4895 /* Figure out the symbol index. */
4896 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
4897 + output_section->reloc_count);
4898 if (link_order->type == bfd_section_reloc_link_order)
4899 {
4900 indx = link_order->u.reloc.p->u.section->target_index;
4901 BFD_ASSERT (indx != 0);
4902 *rel_hash_ptr = NULL;
4903 }
4904 else
4905 {
4906 struct elf_link_hash_entry *h;
4907
4908 /* Treat a reloc against a defined symbol as though it were
4909 actually against the section. */
4910 h = ((struct elf_link_hash_entry *)
4911 bfd_wrapped_link_hash_lookup (output_bfd, info,
4912 link_order->u.reloc.p->u.name,
4913 false, false, true));
4914 if (h != NULL
4915 && (h->root.type == bfd_link_hash_defined
4916 || h->root.type == bfd_link_hash_defweak))
4917 {
4918 asection *section;
4919
4920 section = h->root.u.def.section;
4921 indx = section->output_section->target_index;
4922 *rel_hash_ptr = NULL;
4923 /* It seems that we ought to add the symbol value to the
4924 addend here, but in practice it has already been added
4925 because it was passed to constructor_callback. */
4926 addend += section->output_section->vma + section->output_offset;
4927 }
4928 else if (h != NULL)
4929 {
4930 /* Setting the index to -2 tells elf_link_output_extsym that
4931 this symbol is used by a reloc. */
4932 h->indx = -2;
4933 *rel_hash_ptr = h;
4934 indx = 0;
4935 }
4936 else
4937 {
4938 if (! ((*info->callbacks->unattached_reloc)
4939 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
4940 (asection *) NULL, (bfd_vma) 0)))
4941 return false;
4942 indx = 0;
4943 }
4944 }
4945
4946 /* If this is an inplace reloc, we must write the addend into the
4947 object file. */
4948 if (howto->partial_inplace && addend != 0)
4949 {
4950 bfd_size_type size;
4951 bfd_reloc_status_type rstat;
4952 bfd_byte *buf;
4953 boolean ok;
4954
4955 size = bfd_get_reloc_size (howto);
4956 buf = (bfd_byte *) bfd_zmalloc (size);
4957 if (buf == (bfd_byte *) NULL)
4958 return false;
4959 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
4960 switch (rstat)
4961 {
4962 case bfd_reloc_ok:
4963 break;
4964 default:
4965 case bfd_reloc_outofrange:
4966 abort ();
4967 case bfd_reloc_overflow:
4968 if (! ((*info->callbacks->reloc_overflow)
4969 (info,
4970 (link_order->type == bfd_section_reloc_link_order
4971 ? bfd_section_name (output_bfd,
4972 link_order->u.reloc.p->u.section)
4973 : link_order->u.reloc.p->u.name),
4974 howto->name, addend, (bfd *) NULL, (asection *) NULL,
4975 (bfd_vma) 0)))
4976 {
4977 free (buf);
4978 return false;
4979 }
4980 break;
4981 }
4982 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
4983 (file_ptr) link_order->offset, size);
4984 free (buf);
4985 if (! ok)
4986 return false;
4987 }
4988
4989 /* The address of a reloc is relative to the section in a
4990 relocateable file, and is a virtual address in an executable
4991 file. */
4992 offset = link_order->offset;
4993 if (! info->relocateable)
4994 offset += output_section->vma;
4995
4996 rel_hdr = &elf_section_data (output_section)->rel_hdr;
4997
4998 if (rel_hdr->sh_type == SHT_REL)
4999 {
5000 Elf_Internal_Rel irel;
5001 Elf_External_Rel *erel;
5002
5003 irel.r_offset = offset;
5004 irel.r_info = ELF_R_INFO (indx, howto->type);
5005 erel = ((Elf_External_Rel *) rel_hdr->contents
5006 + output_section->reloc_count);
5007 elf_swap_reloc_out (output_bfd, &irel, erel);
5008 }
5009 else
5010 {
5011 Elf_Internal_Rela irela;
5012 Elf_External_Rela *erela;
5013
5014 irela.r_offset = offset;
5015 irela.r_info = ELF_R_INFO (indx, howto->type);
5016 irela.r_addend = addend;
5017 erela = ((Elf_External_Rela *) rel_hdr->contents
5018 + output_section->reloc_count);
5019 elf_swap_reloca_out (output_bfd, &irela, erela);
5020 }
5021
5022 ++output_section->reloc_count;
5023
5024 return true;
5025 }
5026
5027 \f
5028 /* Allocate a pointer to live in a linker created section. */
5029
5030 boolean
5031 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5032 bfd *abfd;
5033 struct bfd_link_info *info;
5034 elf_linker_section_t *lsect;
5035 struct elf_link_hash_entry *h;
5036 const Elf_Internal_Rela *rel;
5037 {
5038 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5039 elf_linker_section_pointers_t *linker_section_ptr;
5040 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5041
5042 BFD_ASSERT (lsect != NULL);
5043
5044 /* Is this a global symbol? */
5045 if (h != NULL)
5046 {
5047 /* Has this symbol already been allocated, if so, our work is done */
5048 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5049 rel->r_addend,
5050 lsect->which))
5051 return true;
5052
5053 ptr_linker_section_ptr = &h->linker_section_pointer;
5054 /* Make sure this symbol is output as a dynamic symbol. */
5055 if (h->dynindx == -1)
5056 {
5057 if (! elf_link_record_dynamic_symbol (info, h))
5058 return false;
5059 }
5060
5061 if (lsect->rel_section)
5062 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5063 }
5064
5065 else /* Allocation of a pointer to a local symbol */
5066 {
5067 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5068
5069 /* Allocate a table to hold the local symbols if first time */
5070 if (!ptr)
5071 {
5072 int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5073 register unsigned int i;
5074
5075 ptr = (elf_linker_section_pointers_t **)
5076 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5077
5078 if (!ptr)
5079 return false;
5080
5081 elf_local_ptr_offsets (abfd) = ptr;
5082 for (i = 0; i < num_symbols; i++)
5083 ptr[i] = (elf_linker_section_pointers_t *)0;
5084 }
5085
5086 /* Has this symbol already been allocated, if so, our work is done */
5087 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5088 rel->r_addend,
5089 lsect->which))
5090 return true;
5091
5092 ptr_linker_section_ptr = &ptr[r_symndx];
5093
5094 if (info->shared)
5095 {
5096 /* If we are generating a shared object, we need to
5097 output a R_<xxx>_RELATIVE reloc so that the
5098 dynamic linker can adjust this GOT entry. */
5099 BFD_ASSERT (lsect->rel_section != NULL);
5100 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5101 }
5102 }
5103
5104 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5105 from internal memory. */
5106 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5107 linker_section_ptr = (elf_linker_section_pointers_t *)
5108 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5109
5110 if (!linker_section_ptr)
5111 return false;
5112
5113 linker_section_ptr->next = *ptr_linker_section_ptr;
5114 linker_section_ptr->addend = rel->r_addend;
5115 linker_section_ptr->which = lsect->which;
5116 linker_section_ptr->written_address_p = false;
5117 *ptr_linker_section_ptr = linker_section_ptr;
5118
5119 #if 0
5120 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5121 {
5122 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5123 lsect->hole_offset += ARCH_SIZE / 8;
5124 lsect->sym_offset += ARCH_SIZE / 8;
5125 if (lsect->sym_hash) /* Bump up symbol value if needed */
5126 {
5127 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5128 #ifdef DEBUG
5129 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5130 lsect->sym_hash->root.root.string,
5131 (long)ARCH_SIZE / 8,
5132 (long)lsect->sym_hash->root.u.def.value);
5133 #endif
5134 }
5135 }
5136 else
5137 #endif
5138 linker_section_ptr->offset = lsect->section->_raw_size;
5139
5140 lsect->section->_raw_size += ARCH_SIZE / 8;
5141
5142 #ifdef DEBUG
5143 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5144 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5145 #endif
5146
5147 return true;
5148 }
5149
5150 \f
5151 #if ARCH_SIZE==64
5152 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5153 #endif
5154 #if ARCH_SIZE==32
5155 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5156 #endif
5157
5158 /* Fill in the address for a pointer generated in alinker section. */
5159
5160 bfd_vma
5161 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5162 bfd *output_bfd;
5163 bfd *input_bfd;
5164 struct bfd_link_info *info;
5165 elf_linker_section_t *lsect;
5166 struct elf_link_hash_entry *h;
5167 bfd_vma relocation;
5168 const Elf_Internal_Rela *rel;
5169 int relative_reloc;
5170 {
5171 elf_linker_section_pointers_t *linker_section_ptr;
5172
5173 BFD_ASSERT (lsect != NULL);
5174
5175 if (h != NULL) /* global symbol */
5176 {
5177 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5178 rel->r_addend,
5179 lsect->which);
5180
5181 BFD_ASSERT (linker_section_ptr != NULL);
5182
5183 if (! elf_hash_table (info)->dynamic_sections_created
5184 || (info->shared
5185 && info->symbolic
5186 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5187 {
5188 /* This is actually a static link, or it is a
5189 -Bsymbolic link and the symbol is defined
5190 locally. We must initialize this entry in the
5191 global section.
5192
5193 When doing a dynamic link, we create a .rela.<xxx>
5194 relocation entry to initialize the value. This
5195 is done in the finish_dynamic_symbol routine. */
5196 if (!linker_section_ptr->written_address_p)
5197 {
5198 linker_section_ptr->written_address_p = true;
5199 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5200 lsect->section->contents + linker_section_ptr->offset);
5201 }
5202 }
5203 }
5204 else /* local symbol */
5205 {
5206 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
5207 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
5208 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
5209 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
5210 rel->r_addend,
5211 lsect->which);
5212
5213 BFD_ASSERT (linker_section_ptr != NULL);
5214
5215 /* Write out pointer if it hasn't been rewritten out before */
5216 if (!linker_section_ptr->written_address_p)
5217 {
5218 linker_section_ptr->written_address_p = true;
5219 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5220 lsect->section->contents + linker_section_ptr->offset);
5221
5222 if (info->shared)
5223 {
5224 asection *srel = lsect->rel_section;
5225 Elf_Internal_Rela outrel;
5226
5227 /* We need to generate a relative reloc for the dynamic linker. */
5228 if (!srel)
5229 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
5230 lsect->rel_name);
5231
5232 BFD_ASSERT (srel != NULL);
5233
5234 outrel.r_offset = (lsect->section->output_section->vma
5235 + lsect->section->output_offset
5236 + linker_section_ptr->offset);
5237 outrel.r_info = ELF_R_INFO (0, relative_reloc);
5238 outrel.r_addend = 0;
5239 elf_swap_reloca_out (output_bfd, &outrel,
5240 (((Elf_External_Rela *)
5241 lsect->section->contents)
5242 + lsect->section->reloc_count));
5243 ++lsect->section->reloc_count;
5244 }
5245 }
5246 }
5247
5248 relocation = (lsect->section->output_offset
5249 + linker_section_ptr->offset
5250 - lsect->hole_offset
5251 - lsect->sym_offset);
5252
5253 #ifdef DEBUG
5254 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
5255 lsect->name, (long)relocation, (long)relocation);
5256 #endif
5257
5258 /* Subtract out the addend, because it will get added back in by the normal
5259 processing. */
5260 return relocation - linker_section_ptr->addend;
5261 }
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