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[thirdparty/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 *override = false;
302 *type_change_ok = false;
303 *size_change_ok = false;
304
305 sec = *psec;
306 bind = ELF_ST_BIND (sym->st_info);
307
308 if (! bfd_is_und_section (sec))
309 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
310 else
311 h = ((struct elf_link_hash_entry *)
312 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
313 if (h == NULL)
314 return false;
315 *sym_hash = h;
316
317 /* This code is for coping with dynamic objects, and is only useful
318 if we are doing an ELF link. */
319 if (info->hash->creator != abfd->xvec)
320 return true;
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 (elf_tdata (abfd)->verdef != NULL
1215 && ! override
1216 && vernum > 1
1217 && 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, LOG_FILE_ALIGN))
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, LOG_FILE_ALIGN))
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 /* If this symbol is not being provided by the linker script, and it is
2107 currently defined by a dynamic object, but not by a regular object,
2108 then clear out any version information because the symbol will not be
2109 associated with the dynamic object any more. */
2110 if (!provide
2111 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2112 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2113 h->verinfo.verdef = NULL;
2114
2115 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2116 h->type = STT_OBJECT;
2117
2118 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2119 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2120 || info->shared)
2121 && h->dynindx == -1)
2122 {
2123 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2124 return false;
2125
2126 /* If this is a weak defined symbol, and we know a corresponding
2127 real symbol from the same dynamic object, make sure the real
2128 symbol is also made into a dynamic symbol. */
2129 if (h->weakdef != NULL
2130 && h->weakdef->dynindx == -1)
2131 {
2132 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2133 return false;
2134 }
2135 }
2136
2137 return true;
2138 }
2139 \f
2140 /* This structure is used to pass information to
2141 elf_link_assign_sym_version. */
2142
2143 struct elf_assign_sym_version_info
2144 {
2145 /* Output BFD. */
2146 bfd *output_bfd;
2147 /* General link information. */
2148 struct bfd_link_info *info;
2149 /* Version tree. */
2150 struct bfd_elf_version_tree *verdefs;
2151 /* Whether we are exporting all dynamic symbols. */
2152 boolean export_dynamic;
2153 /* Whether we removed any symbols from the dynamic symbol table. */
2154 boolean removed_dynamic;
2155 /* Whether we had a failure. */
2156 boolean failed;
2157 };
2158
2159 /* This structure is used to pass information to
2160 elf_link_find_version_dependencies. */
2161
2162 struct elf_find_verdep_info
2163 {
2164 /* Output BFD. */
2165 bfd *output_bfd;
2166 /* General link information. */
2167 struct bfd_link_info *info;
2168 /* The number of dependencies. */
2169 unsigned int vers;
2170 /* Whether we had a failure. */
2171 boolean failed;
2172 };
2173
2174 /* Array used to determine the number of hash table buckets to use
2175 based on the number of symbols there are. If there are fewer than
2176 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2177 fewer than 37 we use 17 buckets, and so forth. We never use more
2178 than 32771 buckets. */
2179
2180 static const size_t elf_buckets[] =
2181 {
2182 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2183 16411, 32771, 0
2184 };
2185
2186 /* Set up the sizes and contents of the ELF dynamic sections. This is
2187 called by the ELF linker emulation before_allocation routine. We
2188 must set the sizes of the sections before the linker sets the
2189 addresses of the various sections. */
2190
2191 boolean
2192 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2193 export_dynamic, filter_shlib,
2194 auxiliary_filters, info, sinterpptr,
2195 verdefs)
2196 bfd *output_bfd;
2197 const char *soname;
2198 const char *rpath;
2199 boolean export_dynamic;
2200 const char *filter_shlib;
2201 const char * const *auxiliary_filters;
2202 struct bfd_link_info *info;
2203 asection **sinterpptr;
2204 struct bfd_elf_version_tree *verdefs;
2205 {
2206 bfd_size_type soname_indx;
2207 bfd *dynobj;
2208 struct elf_backend_data *bed;
2209 bfd_size_type old_dynsymcount;
2210 struct elf_assign_sym_version_info asvinfo;
2211
2212 *sinterpptr = NULL;
2213
2214 soname_indx = -1;
2215
2216 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2217 return true;
2218
2219 /* The backend may have to create some sections regardless of whether
2220 we're dynamic or not. */
2221 bed = get_elf_backend_data (output_bfd);
2222 if (bed->elf_backend_always_size_sections
2223 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2224 return false;
2225
2226 dynobj = elf_hash_table (info)->dynobj;
2227
2228 /* If there were no dynamic objects in the link, there is nothing to
2229 do here. */
2230 if (dynobj == NULL)
2231 return true;
2232
2233 /* If we are supposed to export all symbols into the dynamic symbol
2234 table (this is not the normal case), then do so. */
2235 if (export_dynamic)
2236 {
2237 struct elf_info_failed eif;
2238
2239 eif.failed = false;
2240 eif.info = info;
2241 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2242 (PTR) &eif);
2243 if (eif.failed)
2244 return false;
2245 }
2246
2247 if (elf_hash_table (info)->dynamic_sections_created)
2248 {
2249 struct elf_info_failed eif;
2250 struct elf_link_hash_entry *h;
2251 bfd_size_type strsize;
2252
2253 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2254 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2255
2256 if (soname != NULL)
2257 {
2258 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2259 soname, true, true);
2260 if (soname_indx == (bfd_size_type) -1
2261 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2262 return false;
2263 }
2264
2265 if (info->symbolic)
2266 {
2267 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2268 return false;
2269 }
2270
2271 if (rpath != NULL)
2272 {
2273 bfd_size_type indx;
2274
2275 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2276 true, true);
2277 if (indx == (bfd_size_type) -1
2278 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2279 return false;
2280 }
2281
2282 if (filter_shlib != NULL)
2283 {
2284 bfd_size_type indx;
2285
2286 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2287 filter_shlib, true, true);
2288 if (indx == (bfd_size_type) -1
2289 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2290 return false;
2291 }
2292
2293 if (auxiliary_filters != NULL)
2294 {
2295 const char * const *p;
2296
2297 for (p = auxiliary_filters; *p != NULL; p++)
2298 {
2299 bfd_size_type indx;
2300
2301 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2302 *p, true, true);
2303 if (indx == (bfd_size_type) -1
2304 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2305 return false;
2306 }
2307 }
2308
2309 /* Attach all the symbols to their version information. */
2310 asvinfo.output_bfd = output_bfd;
2311 asvinfo.info = info;
2312 asvinfo.verdefs = verdefs;
2313 asvinfo.export_dynamic = export_dynamic;
2314 asvinfo.removed_dynamic = false;
2315 asvinfo.failed = false;
2316
2317 elf_link_hash_traverse (elf_hash_table (info),
2318 elf_link_assign_sym_version,
2319 (PTR) &asvinfo);
2320 if (asvinfo.failed)
2321 return false;
2322
2323 /* Find all symbols which were defined in a dynamic object and make
2324 the backend pick a reasonable value for them. */
2325 eif.failed = false;
2326 eif.info = info;
2327 elf_link_hash_traverse (elf_hash_table (info),
2328 elf_adjust_dynamic_symbol,
2329 (PTR) &eif);
2330 if (eif.failed)
2331 return false;
2332
2333 /* Add some entries to the .dynamic section. We fill in some of the
2334 values later, in elf_bfd_final_link, but we must add the entries
2335 now so that we know the final size of the .dynamic section. */
2336 h = elf_link_hash_lookup (elf_hash_table (info), "_init", 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_INIT, 0))
2343 return false;
2344 }
2345 h = elf_link_hash_lookup (elf_hash_table (info), "_fini", false,
2346 false, false);
2347 if (h != NULL
2348 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2349 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2350 {
2351 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2352 return false;
2353 }
2354 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2355 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2356 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2357 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2358 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2359 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2360 sizeof (Elf_External_Sym)))
2361 return false;
2362 }
2363
2364 /* The backend must work out the sizes of all the other dynamic
2365 sections. */
2366 old_dynsymcount = elf_hash_table (info)->dynsymcount;
2367 if (! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2368 return false;
2369
2370 if (elf_hash_table (info)->dynamic_sections_created)
2371 {
2372 size_t dynsymcount;
2373 asection *s;
2374 size_t i;
2375 size_t bucketcount = 0;
2376 Elf_Internal_Sym isym;
2377
2378 /* Set up the version definition section. */
2379 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2380 BFD_ASSERT (s != NULL);
2381
2382 /* We may have created additional version definitions if we are
2383 just linking a regular application. */
2384 verdefs = asvinfo.verdefs;
2385
2386 if (verdefs == NULL)
2387 {
2388 asection **spp;
2389
2390 /* Don't include this section in the output file. */
2391 for (spp = &output_bfd->sections;
2392 *spp != s->output_section;
2393 spp = &(*spp)->next)
2394 ;
2395 *spp = s->output_section->next;
2396 --output_bfd->section_count;
2397 }
2398 else
2399 {
2400 unsigned int cdefs;
2401 bfd_size_type size;
2402 struct bfd_elf_version_tree *t;
2403 bfd_byte *p;
2404 Elf_Internal_Verdef def;
2405 Elf_Internal_Verdaux defaux;
2406
2407 if (asvinfo.removed_dynamic)
2408 {
2409 /* Some dynamic symbols were changed to be local
2410 symbols. In this case, we renumber all of the
2411 dynamic symbols, so that we don't have a hole. If
2412 the backend changed dynsymcount, then assume that the
2413 new symbols are at the start. This is the case on
2414 the MIPS. FIXME: The names of the removed symbols
2415 will still be in the dynamic string table, wasting
2416 space. */
2417 elf_hash_table (info)->dynsymcount =
2418 1 + (elf_hash_table (info)->dynsymcount - old_dynsymcount);
2419 elf_link_hash_traverse (elf_hash_table (info),
2420 elf_link_renumber_dynsyms,
2421 (PTR) info);
2422 }
2423
2424 cdefs = 0;
2425 size = 0;
2426
2427 /* Make space for the base version. */
2428 size += sizeof (Elf_External_Verdef);
2429 size += sizeof (Elf_External_Verdaux);
2430 ++cdefs;
2431
2432 for (t = verdefs; t != NULL; t = t->next)
2433 {
2434 struct bfd_elf_version_deps *n;
2435
2436 size += sizeof (Elf_External_Verdef);
2437 size += sizeof (Elf_External_Verdaux);
2438 ++cdefs;
2439
2440 for (n = t->deps; n != NULL; n = n->next)
2441 size += sizeof (Elf_External_Verdaux);
2442 }
2443
2444 s->_raw_size = size;
2445 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2446 if (s->contents == NULL && s->_raw_size != 0)
2447 return false;
2448
2449 /* Fill in the version definition section. */
2450
2451 p = s->contents;
2452
2453 def.vd_version = VER_DEF_CURRENT;
2454 def.vd_flags = VER_FLG_BASE;
2455 def.vd_ndx = 1;
2456 def.vd_cnt = 1;
2457 def.vd_aux = sizeof (Elf_External_Verdef);
2458 def.vd_next = (sizeof (Elf_External_Verdef)
2459 + sizeof (Elf_External_Verdaux));
2460
2461 if (soname_indx != -1)
2462 {
2463 def.vd_hash = bfd_elf_hash ((const unsigned char *) soname);
2464 defaux.vda_name = soname_indx;
2465 }
2466 else
2467 {
2468 const char *name;
2469 bfd_size_type indx;
2470
2471 name = output_bfd->filename;
2472 def.vd_hash = bfd_elf_hash ((const unsigned char *) name);
2473 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2474 name, true, false);
2475 if (indx == (bfd_size_type) -1)
2476 return false;
2477 defaux.vda_name = indx;
2478 }
2479 defaux.vda_next = 0;
2480
2481 _bfd_elf_swap_verdef_out (output_bfd, &def,
2482 (Elf_External_Verdef *)p);
2483 p += sizeof (Elf_External_Verdef);
2484 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2485 (Elf_External_Verdaux *) p);
2486 p += sizeof (Elf_External_Verdaux);
2487
2488 for (t = verdefs; t != NULL; t = t->next)
2489 {
2490 unsigned int cdeps;
2491 struct bfd_elf_version_deps *n;
2492 struct elf_link_hash_entry *h;
2493
2494 cdeps = 0;
2495 for (n = t->deps; n != NULL; n = n->next)
2496 ++cdeps;
2497
2498 /* Add a symbol representing this version. */
2499 h = NULL;
2500 if (! (_bfd_generic_link_add_one_symbol
2501 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
2502 (bfd_vma) 0, (const char *) NULL, false,
2503 get_elf_backend_data (dynobj)->collect,
2504 (struct bfd_link_hash_entry **) &h)))
2505 return false;
2506 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
2507 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2508 h->type = STT_OBJECT;
2509 h->verinfo.vertree = t;
2510
2511 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2512 return false;
2513
2514 def.vd_version = VER_DEF_CURRENT;
2515 def.vd_flags = 0;
2516 if (t->globals == NULL && t->locals == NULL && ! t->used)
2517 def.vd_flags |= VER_FLG_WEAK;
2518 def.vd_ndx = t->vernum + 1;
2519 def.vd_cnt = cdeps + 1;
2520 def.vd_hash = bfd_elf_hash ((const unsigned char *) t->name);
2521 def.vd_aux = sizeof (Elf_External_Verdef);
2522 if (t->next != NULL)
2523 def.vd_next = (sizeof (Elf_External_Verdef)
2524 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
2525 else
2526 def.vd_next = 0;
2527
2528 _bfd_elf_swap_verdef_out (output_bfd, &def,
2529 (Elf_External_Verdef *) p);
2530 p += sizeof (Elf_External_Verdef);
2531
2532 defaux.vda_name = h->dynstr_index;
2533 if (t->deps == NULL)
2534 defaux.vda_next = 0;
2535 else
2536 defaux.vda_next = sizeof (Elf_External_Verdaux);
2537 t->name_indx = defaux.vda_name;
2538
2539 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2540 (Elf_External_Verdaux *) p);
2541 p += sizeof (Elf_External_Verdaux);
2542
2543 for (n = t->deps; n != NULL; n = n->next)
2544 {
2545 if (n->version_needed == NULL)
2546 {
2547 /* This can happen if there was an error in the
2548 version script. */
2549 defaux.vda_name = 0;
2550 }
2551 else
2552 defaux.vda_name = n->version_needed->name_indx;
2553 if (n->next == NULL)
2554 defaux.vda_next = 0;
2555 else
2556 defaux.vda_next = sizeof (Elf_External_Verdaux);
2557
2558 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2559 (Elf_External_Verdaux *) p);
2560 p += sizeof (Elf_External_Verdaux);
2561 }
2562 }
2563
2564 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
2565 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
2566 return false;
2567
2568 elf_tdata (output_bfd)->cverdefs = cdefs;
2569 }
2570
2571 /* Work out the size of the version reference section. */
2572
2573 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
2574 BFD_ASSERT (s != NULL);
2575 {
2576 struct elf_find_verdep_info sinfo;
2577
2578 sinfo.output_bfd = output_bfd;
2579 sinfo.info = info;
2580 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
2581 if (sinfo.vers == 0)
2582 sinfo.vers = 1;
2583 sinfo.failed = false;
2584
2585 elf_link_hash_traverse (elf_hash_table (info),
2586 elf_link_find_version_dependencies,
2587 (PTR) &sinfo);
2588
2589 if (elf_tdata (output_bfd)->verref == NULL)
2590 {
2591 asection **spp;
2592
2593 /* We don't have any version definitions, so we can just
2594 remove the section. */
2595
2596 for (spp = &output_bfd->sections;
2597 *spp != s->output_section;
2598 spp = &(*spp)->next)
2599 ;
2600 *spp = s->output_section->next;
2601 --output_bfd->section_count;
2602 }
2603 else
2604 {
2605 Elf_Internal_Verneed *t;
2606 unsigned int size;
2607 unsigned int crefs;
2608 bfd_byte *p;
2609
2610 /* Build the version definition section. */
2611 size = 0;
2612 crefs = 0;
2613 for (t = elf_tdata (output_bfd)->verref;
2614 t != NULL;
2615 t = t->vn_nextref)
2616 {
2617 Elf_Internal_Vernaux *a;
2618
2619 size += sizeof (Elf_External_Verneed);
2620 ++crefs;
2621 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2622 size += sizeof (Elf_External_Vernaux);
2623 }
2624
2625 s->_raw_size = size;
2626 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
2627 if (s->contents == NULL)
2628 return false;
2629
2630 p = s->contents;
2631 for (t = elf_tdata (output_bfd)->verref;
2632 t != NULL;
2633 t = t->vn_nextref)
2634 {
2635 unsigned int caux;
2636 Elf_Internal_Vernaux *a;
2637 bfd_size_type indx;
2638
2639 caux = 0;
2640 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2641 ++caux;
2642
2643 t->vn_version = VER_NEED_CURRENT;
2644 t->vn_cnt = caux;
2645 if (elf_dt_name (t->vn_bfd) != NULL)
2646 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2647 elf_dt_name (t->vn_bfd),
2648 true, false);
2649 else
2650 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2651 t->vn_bfd->filename, true, false);
2652 if (indx == (bfd_size_type) -1)
2653 return false;
2654 t->vn_file = indx;
2655 t->vn_aux = sizeof (Elf_External_Verneed);
2656 if (t->vn_nextref == NULL)
2657 t->vn_next = 0;
2658 else
2659 t->vn_next = (sizeof (Elf_External_Verneed)
2660 + caux * sizeof (Elf_External_Vernaux));
2661
2662 _bfd_elf_swap_verneed_out (output_bfd, t,
2663 (Elf_External_Verneed *) p);
2664 p += sizeof (Elf_External_Verneed);
2665
2666 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2667 {
2668 a->vna_hash = bfd_elf_hash ((const unsigned char *)
2669 a->vna_nodename);
2670 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2671 a->vna_nodename, true, false);
2672 if (indx == (bfd_size_type) -1)
2673 return false;
2674 a->vna_name = indx;
2675 if (a->vna_nextptr == NULL)
2676 a->vna_next = 0;
2677 else
2678 a->vna_next = sizeof (Elf_External_Vernaux);
2679
2680 _bfd_elf_swap_vernaux_out (output_bfd, a,
2681 (Elf_External_Vernaux *) p);
2682 p += sizeof (Elf_External_Vernaux);
2683 }
2684 }
2685
2686 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
2687 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
2688 return false;
2689
2690 elf_tdata (output_bfd)->cverrefs = crefs;
2691 }
2692 }
2693
2694 dynsymcount = elf_hash_table (info)->dynsymcount;
2695
2696 /* Work out the size of the symbol version section. */
2697 s = bfd_get_section_by_name (dynobj, ".gnu.version");
2698 BFD_ASSERT (s != NULL);
2699 if (dynsymcount == 0
2700 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
2701 {
2702 asection **spp;
2703
2704 /* We don't need any symbol versions; just discard the
2705 section. */
2706 for (spp = &output_bfd->sections;
2707 *spp != s->output_section;
2708 spp = &(*spp)->next)
2709 ;
2710 *spp = s->output_section->next;
2711 --output_bfd->section_count;
2712 }
2713 else
2714 {
2715 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
2716 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
2717 if (s->contents == NULL)
2718 return false;
2719
2720 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
2721 return false;
2722 }
2723
2724 /* Set the size of the .dynsym and .hash sections. We counted
2725 the number of dynamic symbols in elf_link_add_object_symbols.
2726 We will build the contents of .dynsym and .hash when we build
2727 the final symbol table, because until then we do not know the
2728 correct value to give the symbols. We built the .dynstr
2729 section as we went along in elf_link_add_object_symbols. */
2730 s = bfd_get_section_by_name (dynobj, ".dynsym");
2731 BFD_ASSERT (s != NULL);
2732 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
2733 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2734 if (s->contents == NULL && s->_raw_size != 0)
2735 return false;
2736
2737 /* The first entry in .dynsym is a dummy symbol. */
2738 isym.st_value = 0;
2739 isym.st_size = 0;
2740 isym.st_name = 0;
2741 isym.st_info = 0;
2742 isym.st_other = 0;
2743 isym.st_shndx = 0;
2744 elf_swap_symbol_out (output_bfd, &isym,
2745 (PTR) (Elf_External_Sym *) s->contents);
2746
2747 for (i = 0; elf_buckets[i] != 0; i++)
2748 {
2749 bucketcount = elf_buckets[i];
2750 if (dynsymcount < elf_buckets[i + 1])
2751 break;
2752 }
2753
2754 s = bfd_get_section_by_name (dynobj, ".hash");
2755 BFD_ASSERT (s != NULL);
2756 s->_raw_size = (2 + bucketcount + dynsymcount) * (ARCH_SIZE / 8);
2757 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2758 if (s->contents == NULL)
2759 return false;
2760 memset (s->contents, 0, (size_t) s->_raw_size);
2761
2762 put_word (output_bfd, bucketcount, s->contents);
2763 put_word (output_bfd, dynsymcount, s->contents + (ARCH_SIZE / 8));
2764
2765 elf_hash_table (info)->bucketcount = bucketcount;
2766
2767 s = bfd_get_section_by_name (dynobj, ".dynstr");
2768 BFD_ASSERT (s != NULL);
2769 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2770
2771 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
2772 return false;
2773 }
2774
2775 return true;
2776 }
2777 \f
2778 /* Fix up the flags for a symbol. This handles various cases which
2779 can only be fixed after all the input files are seen. This is
2780 currently called by both adjust_dynamic_symbol and
2781 assign_sym_version, which is unnecessary but perhaps more robust in
2782 the face of future changes. */
2783
2784 static boolean
2785 elf_fix_symbol_flags (h, eif)
2786 struct elf_link_hash_entry *h;
2787 struct elf_info_failed *eif;
2788 {
2789 /* If this symbol was mentioned in a non-ELF file, try to set
2790 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2791 permit a non-ELF file to correctly refer to a symbol defined in
2792 an ELF dynamic object. */
2793 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
2794 {
2795 if (h->root.type != bfd_link_hash_defined
2796 && h->root.type != bfd_link_hash_defweak)
2797 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2798 else
2799 {
2800 if (h->root.u.def.section->owner != NULL
2801 && (bfd_get_flavour (h->root.u.def.section->owner)
2802 == bfd_target_elf_flavour))
2803 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2804 else
2805 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2806 }
2807
2808 if (h->dynindx == -1
2809 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2810 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
2811 {
2812 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
2813 {
2814 eif->failed = true;
2815 return false;
2816 }
2817 }
2818 }
2819
2820 /* If this is a final link, and the symbol was defined as a common
2821 symbol in a regular object file, and there was no definition in
2822 any dynamic object, then the linker will have allocated space for
2823 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
2824 flag will not have been set. */
2825 if (h->root.type == bfd_link_hash_defined
2826 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
2827 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
2828 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2829 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2830 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2831
2832 /* If -Bsymbolic was used (which means to bind references to global
2833 symbols to the definition within the shared object), and this
2834 symbol was defined in a regular object, then it actually doesn't
2835 need a PLT entry. */
2836 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
2837 && eif->info->shared
2838 && eif->info->symbolic
2839 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2840 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
2841
2842 return true;
2843 }
2844
2845 /* Make the backend pick a good value for a dynamic symbol. This is
2846 called via elf_link_hash_traverse, and also calls itself
2847 recursively. */
2848
2849 static boolean
2850 elf_adjust_dynamic_symbol (h, data)
2851 struct elf_link_hash_entry *h;
2852 PTR data;
2853 {
2854 struct elf_info_failed *eif = (struct elf_info_failed *) data;
2855 bfd *dynobj;
2856 struct elf_backend_data *bed;
2857
2858 /* Ignore indirect symbols. These are added by the versioning code. */
2859 if (h->root.type == bfd_link_hash_indirect)
2860 return true;
2861
2862 /* Fix the symbol flags. */
2863 if (! elf_fix_symbol_flags (h, eif))
2864 return false;
2865
2866 /* If this symbol does not require a PLT entry, and it is not
2867 defined by a dynamic object, or is not referenced by a regular
2868 object, ignore it. We do have to handle a weak defined symbol,
2869 even if no regular object refers to it, if we decided to add it
2870 to the dynamic symbol table. FIXME: Do we normally need to worry
2871 about symbols which are defined by one dynamic object and
2872 referenced by another one? */
2873 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
2874 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
2875 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2876 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
2877 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
2878 return true;
2879
2880 /* If we've already adjusted this symbol, don't do it again. This
2881 can happen via a recursive call. */
2882 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
2883 return true;
2884
2885 /* Don't look at this symbol again. Note that we must set this
2886 after checking the above conditions, because we may look at a
2887 symbol once, decide not to do anything, and then get called
2888 recursively later after REF_REGULAR is set below. */
2889 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
2890
2891 /* If this is a weak definition, and we know a real definition, and
2892 the real symbol is not itself defined by a regular object file,
2893 then get a good value for the real definition. We handle the
2894 real symbol first, for the convenience of the backend routine.
2895
2896 Note that there is a confusing case here. If the real definition
2897 is defined by a regular object file, we don't get the real symbol
2898 from the dynamic object, but we do get the weak symbol. If the
2899 processor backend uses a COPY reloc, then if some routine in the
2900 dynamic object changes the real symbol, we will not see that
2901 change in the corresponding weak symbol. This is the way other
2902 ELF linkers work as well, and seems to be a result of the shared
2903 library model.
2904
2905 I will clarify this issue. Most SVR4 shared libraries define the
2906 variable _timezone and define timezone as a weak synonym. The
2907 tzset call changes _timezone. If you write
2908 extern int timezone;
2909 int _timezone = 5;
2910 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2911 you might expect that, since timezone is a synonym for _timezone,
2912 the same number will print both times. However, if the processor
2913 backend uses a COPY reloc, then actually timezone will be copied
2914 into your process image, and, since you define _timezone
2915 yourself, _timezone will not. Thus timezone and _timezone will
2916 wind up at different memory locations. The tzset call will set
2917 _timezone, leaving timezone unchanged. */
2918
2919 if (h->weakdef != NULL)
2920 {
2921 struct elf_link_hash_entry *weakdef;
2922
2923 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2924 || h->root.type == bfd_link_hash_defweak);
2925 weakdef = h->weakdef;
2926 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2927 || weakdef->root.type == bfd_link_hash_defweak);
2928 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
2929 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2930 {
2931 /* This symbol is defined by a regular object file, so we
2932 will not do anything special. Clear weakdef for the
2933 convenience of the processor backend. */
2934 h->weakdef = NULL;
2935 }
2936 else
2937 {
2938 /* There is an implicit reference by a regular object file
2939 via the weak symbol. */
2940 weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2941 if (! elf_adjust_dynamic_symbol (weakdef, (PTR) eif))
2942 return false;
2943 }
2944 }
2945
2946 dynobj = elf_hash_table (eif->info)->dynobj;
2947 bed = get_elf_backend_data (dynobj);
2948 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2949 {
2950 eif->failed = true;
2951 return false;
2952 }
2953
2954 return true;
2955 }
2956 \f
2957 /* This routine is used to export all defined symbols into the dynamic
2958 symbol table. It is called via elf_link_hash_traverse. */
2959
2960 static boolean
2961 elf_export_symbol (h, data)
2962 struct elf_link_hash_entry *h;
2963 PTR data;
2964 {
2965 struct elf_info_failed *eif = (struct elf_info_failed *) data;
2966
2967 /* Ignore indirect symbols. These are added by the versioning code. */
2968 if (h->root.type == bfd_link_hash_indirect)
2969 return true;
2970
2971 if (h->dynindx == -1
2972 && (h->elf_link_hash_flags
2973 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
2974 {
2975 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
2976 {
2977 eif->failed = true;
2978 return false;
2979 }
2980 }
2981
2982 return true;
2983 }
2984 \f
2985 /* Look through the symbols which are defined in other shared
2986 libraries and referenced here. Update the list of version
2987 dependencies. This will be put into the .gnu.version_r section.
2988 This function is called via elf_link_hash_traverse. */
2989
2990 static boolean
2991 elf_link_find_version_dependencies (h, data)
2992 struct elf_link_hash_entry *h;
2993 PTR data;
2994 {
2995 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
2996 Elf_Internal_Verneed *t;
2997 Elf_Internal_Vernaux *a;
2998
2999 /* We only care about symbols defined in shared objects with version
3000 information. */
3001 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3002 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3003 || h->dynindx == -1
3004 || h->verinfo.verdef == NULL)
3005 return true;
3006
3007 /* See if we already know about this version. */
3008 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3009 {
3010 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3011 continue;
3012
3013 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3014 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3015 return true;
3016
3017 break;
3018 }
3019
3020 /* This is a new version. Add it to tree we are building. */
3021
3022 if (t == NULL)
3023 {
3024 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3025 if (t == NULL)
3026 {
3027 rinfo->failed = true;
3028 return false;
3029 }
3030
3031 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3032 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3033 elf_tdata (rinfo->output_bfd)->verref = t;
3034 }
3035
3036 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3037
3038 /* Note that we are copying a string pointer here, and testing it
3039 above. If bfd_elf_string_from_elf_section is ever changed to
3040 discard the string data when low in memory, this will have to be
3041 fixed. */
3042 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3043
3044 a->vna_flags = h->verinfo.verdef->vd_flags;
3045 a->vna_nextptr = t->vn_auxptr;
3046
3047 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3048 ++rinfo->vers;
3049
3050 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3051
3052 t->vn_auxptr = a;
3053
3054 return true;
3055 }
3056
3057 /* Figure out appropriate versions for all the symbols. We may not
3058 have the version number script until we have read all of the input
3059 files, so until that point we don't know which symbols should be
3060 local. This function is called via elf_link_hash_traverse. */
3061
3062 static boolean
3063 elf_link_assign_sym_version (h, data)
3064 struct elf_link_hash_entry *h;
3065 PTR data;
3066 {
3067 struct elf_assign_sym_version_info *sinfo =
3068 (struct elf_assign_sym_version_info *) data;
3069 struct bfd_link_info *info = sinfo->info;
3070 struct elf_info_failed eif;
3071 char *p;
3072
3073 /* Fix the symbol flags. */
3074 eif.failed = false;
3075 eif.info = info;
3076 if (! elf_fix_symbol_flags (h, &eif))
3077 {
3078 if (eif.failed)
3079 sinfo->failed = true;
3080 return false;
3081 }
3082
3083 /* We only need version numbers for symbols defined in regular
3084 objects. */
3085 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3086 return true;
3087
3088 p = strchr (h->root.root.string, ELF_VER_CHR);
3089 if (p != NULL && h->verinfo.vertree == NULL)
3090 {
3091 struct bfd_elf_version_tree *t;
3092 boolean hidden;
3093
3094 hidden = true;
3095
3096 /* There are two consecutive ELF_VER_CHR characters if this is
3097 not a hidden symbol. */
3098 ++p;
3099 if (*p == ELF_VER_CHR)
3100 {
3101 hidden = false;
3102 ++p;
3103 }
3104
3105 /* If there is no version string, we can just return out. */
3106 if (*p == '\0')
3107 {
3108 if (hidden)
3109 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3110 return true;
3111 }
3112
3113 /* Look for the version. If we find it, it is no longer weak. */
3114 for (t = sinfo->verdefs; t != NULL; t = t->next)
3115 {
3116 if (strcmp (t->name, p) == 0)
3117 {
3118 int len;
3119 char *alc;
3120 struct bfd_elf_version_expr *d;
3121
3122 len = p - h->root.root.string;
3123 alc = bfd_alloc (sinfo->output_bfd, len);
3124 if (alc == NULL)
3125 return false;
3126 strncpy (alc, h->root.root.string, len - 1);
3127 alc[len - 1] = '\0';
3128 if (alc[len - 2] == ELF_VER_CHR)
3129 alc[len - 2] = '\0';
3130
3131 h->verinfo.vertree = t;
3132 t->used = true;
3133 d = NULL;
3134
3135 if (t->globals != NULL)
3136 {
3137 for (d = t->globals; d != NULL; d = d->next)
3138 {
3139 if ((d->match[0] == '*' && d->match[1] == '\0')
3140 || fnmatch (d->match, alc, 0) == 0)
3141 break;
3142 }
3143 }
3144
3145 /* See if there is anything to force this symbol to
3146 local scope. */
3147 if (d == NULL && t->locals != NULL)
3148 {
3149 for (d = t->locals; d != NULL; d = d->next)
3150 {
3151 if ((d->match[0] == '*' && d->match[1] == '\0')
3152 || fnmatch (d->match, alc, 0) == 0)
3153 {
3154 if (h->dynindx != -1
3155 && info->shared
3156 && ! sinfo->export_dynamic)
3157 {
3158 sinfo->removed_dynamic = true;
3159 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3160 h->elf_link_hash_flags &=~
3161 ELF_LINK_HASH_NEEDS_PLT;
3162 h->dynindx = -1;
3163 /* FIXME: The name of the symbol has
3164 already been recorded in the dynamic
3165 string table section. */
3166 }
3167
3168 break;
3169 }
3170 }
3171 }
3172
3173 bfd_release (sinfo->output_bfd, alc);
3174 break;
3175 }
3176 }
3177
3178 /* If we are building an application, we need to create a
3179 version node for this version. */
3180 if (t == NULL && ! info->shared)
3181 {
3182 struct bfd_elf_version_tree **pp;
3183 int version_index;
3184
3185 /* If we aren't going to export this symbol, we don't need
3186 to worry about it. */
3187 if (h->dynindx == -1)
3188 return true;
3189
3190 t = ((struct bfd_elf_version_tree *)
3191 bfd_alloc (sinfo->output_bfd, sizeof *t));
3192 if (t == NULL)
3193 {
3194 sinfo->failed = true;
3195 return false;
3196 }
3197
3198 t->next = NULL;
3199 t->name = p;
3200 t->globals = NULL;
3201 t->locals = NULL;
3202 t->deps = NULL;
3203 t->name_indx = (unsigned int) -1;
3204 t->used = true;
3205
3206 version_index = 1;
3207 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3208 ++version_index;
3209 t->vernum = version_index;
3210
3211 *pp = t;
3212
3213 h->verinfo.vertree = t;
3214 }
3215 else if (t == NULL)
3216 {
3217 /* We could not find the version for a symbol when
3218 generating a shared archive. Return an error. */
3219 (*_bfd_error_handler)
3220 ("%s: undefined version name %s",
3221 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3222 bfd_set_error (bfd_error_bad_value);
3223 sinfo->failed = true;
3224 return false;
3225 }
3226
3227 if (hidden)
3228 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3229 }
3230
3231 /* If we don't have a version for this symbol, see if we can find
3232 something. */
3233 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3234 {
3235 struct bfd_elf_version_tree *t;
3236 struct bfd_elf_version_tree *deflt;
3237 struct bfd_elf_version_expr *d;
3238
3239 /* See if can find what version this symbol is in. If the
3240 symbol is supposed to be local, then don't actually register
3241 it. */
3242 deflt = NULL;
3243 for (t = sinfo->verdefs; t != NULL; t = t->next)
3244 {
3245 if (t->globals != NULL)
3246 {
3247 for (d = t->globals; d != NULL; d = d->next)
3248 {
3249 if (fnmatch (d->match, h->root.root.string, 0) == 0)
3250 {
3251 h->verinfo.vertree = t;
3252 break;
3253 }
3254 }
3255
3256 if (d != NULL)
3257 break;
3258 }
3259
3260 if (t->locals != NULL)
3261 {
3262 for (d = t->locals; d != NULL; d = d->next)
3263 {
3264 if (d->match[0] == '*' && d->match[1] == '\0')
3265 deflt = t;
3266 else if (fnmatch (d->match, h->root.root.string, 0) == 0)
3267 {
3268 h->verinfo.vertree = t;
3269 if (h->dynindx != -1
3270 && info->shared
3271 && ! sinfo->export_dynamic)
3272 {
3273 sinfo->removed_dynamic = true;
3274 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3275 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3276 h->dynindx = -1;
3277 /* FIXME: The name of the symbol has already
3278 been recorded in the dynamic string table
3279 section. */
3280 }
3281 break;
3282 }
3283 }
3284
3285 if (d != NULL)
3286 break;
3287 }
3288 }
3289
3290 if (deflt != NULL && h->verinfo.vertree == NULL)
3291 {
3292 h->verinfo.vertree = deflt;
3293 if (h->dynindx != -1
3294 && info->shared
3295 && ! sinfo->export_dynamic)
3296 {
3297 sinfo->removed_dynamic = true;
3298 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3299 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3300 h->dynindx = -1;
3301 /* FIXME: The name of the symbol has already been
3302 recorded in the dynamic string table section. */
3303 }
3304 }
3305 }
3306
3307 return true;
3308 }
3309
3310 /* This function is used to renumber the dynamic symbols, if some of
3311 them are removed because they are marked as local. This is called
3312 via elf_link_hash_traverse. */
3313
3314 static boolean
3315 elf_link_renumber_dynsyms (h, data)
3316 struct elf_link_hash_entry *h;
3317 PTR data;
3318 {
3319 struct bfd_link_info *info = (struct bfd_link_info *) data;
3320
3321 if (h->dynindx != -1)
3322 {
3323 h->dynindx = elf_hash_table (info)->dynsymcount;
3324 ++elf_hash_table (info)->dynsymcount;
3325 }
3326
3327 return true;
3328 }
3329 \f
3330 /* Final phase of ELF linker. */
3331
3332 /* A structure we use to avoid passing large numbers of arguments. */
3333
3334 struct elf_final_link_info
3335 {
3336 /* General link information. */
3337 struct bfd_link_info *info;
3338 /* Output BFD. */
3339 bfd *output_bfd;
3340 /* Symbol string table. */
3341 struct bfd_strtab_hash *symstrtab;
3342 /* .dynsym section. */
3343 asection *dynsym_sec;
3344 /* .hash section. */
3345 asection *hash_sec;
3346 /* symbol version section (.gnu.version). */
3347 asection *symver_sec;
3348 /* Buffer large enough to hold contents of any section. */
3349 bfd_byte *contents;
3350 /* Buffer large enough to hold external relocs of any section. */
3351 PTR external_relocs;
3352 /* Buffer large enough to hold internal relocs of any section. */
3353 Elf_Internal_Rela *internal_relocs;
3354 /* Buffer large enough to hold external local symbols of any input
3355 BFD. */
3356 Elf_External_Sym *external_syms;
3357 /* Buffer large enough to hold internal local symbols of any input
3358 BFD. */
3359 Elf_Internal_Sym *internal_syms;
3360 /* Array large enough to hold a symbol index for each local symbol
3361 of any input BFD. */
3362 long *indices;
3363 /* Array large enough to hold a section pointer for each local
3364 symbol of any input BFD. */
3365 asection **sections;
3366 /* Buffer to hold swapped out symbols. */
3367 Elf_External_Sym *symbuf;
3368 /* Number of swapped out symbols in buffer. */
3369 size_t symbuf_count;
3370 /* Number of symbols which fit in symbuf. */
3371 size_t symbuf_size;
3372 };
3373
3374 static boolean elf_link_output_sym
3375 PARAMS ((struct elf_final_link_info *, const char *,
3376 Elf_Internal_Sym *, asection *));
3377 static boolean elf_link_flush_output_syms
3378 PARAMS ((struct elf_final_link_info *));
3379 static boolean elf_link_output_extsym
3380 PARAMS ((struct elf_link_hash_entry *, PTR));
3381 static boolean elf_link_input_bfd
3382 PARAMS ((struct elf_final_link_info *, bfd *));
3383 static boolean elf_reloc_link_order
3384 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3385 struct bfd_link_order *));
3386
3387 /* This struct is used to pass information to elf_link_output_extsym. */
3388
3389 struct elf_outext_info
3390 {
3391 boolean failed;
3392 boolean localsyms;
3393 struct elf_final_link_info *finfo;
3394 };
3395
3396 /* Do the final step of an ELF link. */
3397
3398 boolean
3399 elf_bfd_final_link (abfd, info)
3400 bfd *abfd;
3401 struct bfd_link_info *info;
3402 {
3403 boolean dynamic;
3404 bfd *dynobj;
3405 struct elf_final_link_info finfo;
3406 register asection *o;
3407 register struct bfd_link_order *p;
3408 register bfd *sub;
3409 size_t max_contents_size;
3410 size_t max_external_reloc_size;
3411 size_t max_internal_reloc_count;
3412 size_t max_sym_count;
3413 file_ptr off;
3414 Elf_Internal_Sym elfsym;
3415 unsigned int i;
3416 Elf_Internal_Shdr *symtab_hdr;
3417 Elf_Internal_Shdr *symstrtab_hdr;
3418 struct elf_backend_data *bed = get_elf_backend_data (abfd);
3419 struct elf_outext_info eoinfo;
3420
3421 if (info->shared)
3422 abfd->flags |= DYNAMIC;
3423
3424 dynamic = elf_hash_table (info)->dynamic_sections_created;
3425 dynobj = elf_hash_table (info)->dynobj;
3426
3427 finfo.info = info;
3428 finfo.output_bfd = abfd;
3429 finfo.symstrtab = elf_stringtab_init ();
3430 if (finfo.symstrtab == NULL)
3431 return false;
3432
3433 if (! dynamic)
3434 {
3435 finfo.dynsym_sec = NULL;
3436 finfo.hash_sec = NULL;
3437 finfo.symver_sec = NULL;
3438 }
3439 else
3440 {
3441 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
3442 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
3443 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
3444 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
3445 /* Note that it is OK if symver_sec is NULL. */
3446 }
3447
3448 finfo.contents = NULL;
3449 finfo.external_relocs = NULL;
3450 finfo.internal_relocs = NULL;
3451 finfo.external_syms = NULL;
3452 finfo.internal_syms = NULL;
3453 finfo.indices = NULL;
3454 finfo.sections = NULL;
3455 finfo.symbuf = NULL;
3456 finfo.symbuf_count = 0;
3457
3458 /* Count up the number of relocations we will output for each output
3459 section, so that we know the sizes of the reloc sections. We
3460 also figure out some maximum sizes. */
3461 max_contents_size = 0;
3462 max_external_reloc_size = 0;
3463 max_internal_reloc_count = 0;
3464 max_sym_count = 0;
3465 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
3466 {
3467 o->reloc_count = 0;
3468
3469 for (p = o->link_order_head; p != NULL; p = p->next)
3470 {
3471 if (p->type == bfd_section_reloc_link_order
3472 || p->type == bfd_symbol_reloc_link_order)
3473 ++o->reloc_count;
3474 else if (p->type == bfd_indirect_link_order)
3475 {
3476 asection *sec;
3477
3478 sec = p->u.indirect.section;
3479
3480 /* Mark all sections which are to be included in the
3481 link. This will normally be every section. We need
3482 to do this so that we can identify any sections which
3483 the linker has decided to not include. */
3484 sec->linker_mark = true;
3485
3486 if (info->relocateable)
3487 o->reloc_count += sec->reloc_count;
3488
3489 if (sec->_raw_size > max_contents_size)
3490 max_contents_size = sec->_raw_size;
3491 if (sec->_cooked_size > max_contents_size)
3492 max_contents_size = sec->_cooked_size;
3493
3494 /* We are interested in just local symbols, not all
3495 symbols. */
3496 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
3497 && (sec->owner->flags & DYNAMIC) == 0)
3498 {
3499 size_t sym_count;
3500
3501 if (elf_bad_symtab (sec->owner))
3502 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
3503 / sizeof (Elf_External_Sym));
3504 else
3505 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
3506
3507 if (sym_count > max_sym_count)
3508 max_sym_count = sym_count;
3509
3510 if ((sec->flags & SEC_RELOC) != 0)
3511 {
3512 size_t ext_size;
3513
3514 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
3515 if (ext_size > max_external_reloc_size)
3516 max_external_reloc_size = ext_size;
3517 if (sec->reloc_count > max_internal_reloc_count)
3518 max_internal_reloc_count = sec->reloc_count;
3519 }
3520 }
3521 }
3522 }
3523
3524 if (o->reloc_count > 0)
3525 o->flags |= SEC_RELOC;
3526 else
3527 {
3528 /* Explicitly clear the SEC_RELOC flag. The linker tends to
3529 set it (this is probably a bug) and if it is set
3530 assign_section_numbers will create a reloc section. */
3531 o->flags &=~ SEC_RELOC;
3532 }
3533
3534 /* If the SEC_ALLOC flag is not set, force the section VMA to
3535 zero. This is done in elf_fake_sections as well, but forcing
3536 the VMA to 0 here will ensure that relocs against these
3537 sections are handled correctly. */
3538 if ((o->flags & SEC_ALLOC) == 0
3539 && ! o->user_set_vma)
3540 o->vma = 0;
3541 }
3542
3543 /* Figure out the file positions for everything but the symbol table
3544 and the relocs. We set symcount to force assign_section_numbers
3545 to create a symbol table. */
3546 abfd->symcount = info->strip == strip_all ? 0 : 1;
3547 BFD_ASSERT (! abfd->output_has_begun);
3548 if (! _bfd_elf_compute_section_file_positions (abfd, info))
3549 goto error_return;
3550
3551 /* That created the reloc sections. Set their sizes, and assign
3552 them file positions, and allocate some buffers. */
3553 for (o = abfd->sections; o != NULL; o = o->next)
3554 {
3555 if ((o->flags & SEC_RELOC) != 0)
3556 {
3557 Elf_Internal_Shdr *rel_hdr;
3558 register struct elf_link_hash_entry **p, **pend;
3559
3560 rel_hdr = &elf_section_data (o)->rel_hdr;
3561
3562 rel_hdr->sh_size = rel_hdr->sh_entsize * o->reloc_count;
3563
3564 /* The contents field must last into write_object_contents,
3565 so we allocate it with bfd_alloc rather than malloc. */
3566 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3567 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3568 goto error_return;
3569
3570 p = ((struct elf_link_hash_entry **)
3571 bfd_malloc (o->reloc_count
3572 * sizeof (struct elf_link_hash_entry *)));
3573 if (p == NULL && o->reloc_count != 0)
3574 goto error_return;
3575 elf_section_data (o)->rel_hashes = p;
3576 pend = p + o->reloc_count;
3577 for (; p < pend; p++)
3578 *p = NULL;
3579
3580 /* Use the reloc_count field as an index when outputting the
3581 relocs. */
3582 o->reloc_count = 0;
3583 }
3584 }
3585
3586 _bfd_elf_assign_file_positions_for_relocs (abfd);
3587
3588 /* We have now assigned file positions for all the sections except
3589 .symtab and .strtab. We start the .symtab section at the current
3590 file position, and write directly to it. We build the .strtab
3591 section in memory. */
3592 abfd->symcount = 0;
3593 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
3594 /* sh_name is set in prep_headers. */
3595 symtab_hdr->sh_type = SHT_SYMTAB;
3596 symtab_hdr->sh_flags = 0;
3597 symtab_hdr->sh_addr = 0;
3598 symtab_hdr->sh_size = 0;
3599 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
3600 /* sh_link is set in assign_section_numbers. */
3601 /* sh_info is set below. */
3602 /* sh_offset is set just below. */
3603 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
3604
3605 off = elf_tdata (abfd)->next_file_pos;
3606 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
3607
3608 /* Note that at this point elf_tdata (abfd)->next_file_pos is
3609 incorrect. We do not yet know the size of the .symtab section.
3610 We correct next_file_pos below, after we do know the size. */
3611
3612 /* Allocate a buffer to hold swapped out symbols. This is to avoid
3613 continuously seeking to the right position in the file. */
3614 if (! info->keep_memory || max_sym_count < 20)
3615 finfo.symbuf_size = 20;
3616 else
3617 finfo.symbuf_size = max_sym_count;
3618 finfo.symbuf = ((Elf_External_Sym *)
3619 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
3620 if (finfo.symbuf == NULL)
3621 goto error_return;
3622
3623 /* Start writing out the symbol table. The first symbol is always a
3624 dummy symbol. */
3625 if (info->strip != strip_all || info->relocateable)
3626 {
3627 elfsym.st_value = 0;
3628 elfsym.st_size = 0;
3629 elfsym.st_info = 0;
3630 elfsym.st_other = 0;
3631 elfsym.st_shndx = SHN_UNDEF;
3632 if (! elf_link_output_sym (&finfo, (const char *) NULL,
3633 &elfsym, bfd_und_section_ptr))
3634 goto error_return;
3635 }
3636
3637 #if 0
3638 /* Some standard ELF linkers do this, but we don't because it causes
3639 bootstrap comparison failures. */
3640 /* Output a file symbol for the output file as the second symbol.
3641 We output this even if we are discarding local symbols, although
3642 I'm not sure if this is correct. */
3643 elfsym.st_value = 0;
3644 elfsym.st_size = 0;
3645 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
3646 elfsym.st_other = 0;
3647 elfsym.st_shndx = SHN_ABS;
3648 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
3649 &elfsym, bfd_abs_section_ptr))
3650 goto error_return;
3651 #endif
3652
3653 /* Output a symbol for each section. We output these even if we are
3654 discarding local symbols, since they are used for relocs. These
3655 symbols have no names. We store the index of each one in the
3656 index field of the section, so that we can find it again when
3657 outputting relocs. */
3658 if (info->strip != strip_all || info->relocateable)
3659 {
3660 elfsym.st_size = 0;
3661 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
3662 elfsym.st_other = 0;
3663 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
3664 {
3665 o = section_from_elf_index (abfd, i);
3666 if (o != NULL)
3667 o->target_index = abfd->symcount;
3668 elfsym.st_shndx = i;
3669 if (info->relocateable || o == NULL)
3670 elfsym.st_value = 0;
3671 else
3672 elfsym.st_value = o->vma;
3673 if (! elf_link_output_sym (&finfo, (const char *) NULL,
3674 &elfsym, o))
3675 goto error_return;
3676 }
3677 }
3678
3679 /* Allocate some memory to hold information read in from the input
3680 files. */
3681 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
3682 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
3683 finfo.internal_relocs = ((Elf_Internal_Rela *)
3684 bfd_malloc (max_internal_reloc_count
3685 * sizeof (Elf_Internal_Rela)));
3686 finfo.external_syms = ((Elf_External_Sym *)
3687 bfd_malloc (max_sym_count
3688 * sizeof (Elf_External_Sym)));
3689 finfo.internal_syms = ((Elf_Internal_Sym *)
3690 bfd_malloc (max_sym_count
3691 * sizeof (Elf_Internal_Sym)));
3692 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
3693 finfo.sections = ((asection **)
3694 bfd_malloc (max_sym_count * sizeof (asection *)));
3695 if ((finfo.contents == NULL && max_contents_size != 0)
3696 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
3697 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
3698 || (finfo.external_syms == NULL && max_sym_count != 0)
3699 || (finfo.internal_syms == NULL && max_sym_count != 0)
3700 || (finfo.indices == NULL && max_sym_count != 0)
3701 || (finfo.sections == NULL && max_sym_count != 0))
3702 goto error_return;
3703
3704 /* Since ELF permits relocations to be against local symbols, we
3705 must have the local symbols available when we do the relocations.
3706 Since we would rather only read the local symbols once, and we
3707 would rather not keep them in memory, we handle all the
3708 relocations for a single input file at the same time.
3709
3710 Unfortunately, there is no way to know the total number of local
3711 symbols until we have seen all of them, and the local symbol
3712 indices precede the global symbol indices. This means that when
3713 we are generating relocateable output, and we see a reloc against
3714 a global symbol, we can not know the symbol index until we have
3715 finished examining all the local symbols to see which ones we are
3716 going to output. To deal with this, we keep the relocations in
3717 memory, and don't output them until the end of the link. This is
3718 an unfortunate waste of memory, but I don't see a good way around
3719 it. Fortunately, it only happens when performing a relocateable
3720 link, which is not the common case. FIXME: If keep_memory is set
3721 we could write the relocs out and then read them again; I don't
3722 know how bad the memory loss will be. */
3723
3724 for (sub = info->input_bfds; sub != NULL; sub = sub->next)
3725 sub->output_has_begun = false;
3726 for (o = abfd->sections; o != NULL; o = o->next)
3727 {
3728 for (p = o->link_order_head; p != NULL; p = p->next)
3729 {
3730 if (p->type == bfd_indirect_link_order
3731 && (bfd_get_flavour (p->u.indirect.section->owner)
3732 == bfd_target_elf_flavour))
3733 {
3734 sub = p->u.indirect.section->owner;
3735 if (! sub->output_has_begun)
3736 {
3737 if (! elf_link_input_bfd (&finfo, sub))
3738 goto error_return;
3739 sub->output_has_begun = true;
3740 }
3741 }
3742 else if (p->type == bfd_section_reloc_link_order
3743 || p->type == bfd_symbol_reloc_link_order)
3744 {
3745 if (! elf_reloc_link_order (abfd, info, o, p))
3746 goto error_return;
3747 }
3748 else
3749 {
3750 if (! _bfd_default_link_order (abfd, info, o, p))
3751 goto error_return;
3752 }
3753 }
3754 }
3755
3756 /* That wrote out all the local symbols. Finish up the symbol table
3757 with the global symbols. */
3758
3759 if (info->strip != strip_all && info->shared)
3760 {
3761 /* Output any global symbols that got converted to local in a
3762 version script. We do this in a separate step since ELF
3763 requires all local symbols to appear prior to any global
3764 symbols. FIXME: We should only do this if some global
3765 symbols were, in fact, converted to become local. FIXME:
3766 Will this work correctly with the Irix 5 linker? */
3767 eoinfo.failed = false;
3768 eoinfo.finfo = &finfo;
3769 eoinfo.localsyms = true;
3770 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
3771 (PTR) &eoinfo);
3772 if (eoinfo.failed)
3773 return false;
3774 }
3775
3776 /* The sh_info field records the index of the first non local
3777 symbol. */
3778 symtab_hdr->sh_info = abfd->symcount;
3779 if (dynamic)
3780 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info = 1;
3781
3782 /* We get the global symbols from the hash table. */
3783 eoinfo.failed = false;
3784 eoinfo.localsyms = false;
3785 eoinfo.finfo = &finfo;
3786 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
3787 (PTR) &eoinfo);
3788 if (eoinfo.failed)
3789 return false;
3790
3791 /* Flush all symbols to the file. */
3792 if (! elf_link_flush_output_syms (&finfo))
3793 return false;
3794
3795 /* Now we know the size of the symtab section. */
3796 off += symtab_hdr->sh_size;
3797
3798 /* Finish up and write out the symbol string table (.strtab)
3799 section. */
3800 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
3801 /* sh_name was set in prep_headers. */
3802 symstrtab_hdr->sh_type = SHT_STRTAB;
3803 symstrtab_hdr->sh_flags = 0;
3804 symstrtab_hdr->sh_addr = 0;
3805 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
3806 symstrtab_hdr->sh_entsize = 0;
3807 symstrtab_hdr->sh_link = 0;
3808 symstrtab_hdr->sh_info = 0;
3809 /* sh_offset is set just below. */
3810 symstrtab_hdr->sh_addralign = 1;
3811
3812 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
3813 elf_tdata (abfd)->next_file_pos = off;
3814
3815 if (abfd->symcount > 0)
3816 {
3817 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
3818 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
3819 return false;
3820 }
3821
3822 /* Adjust the relocs to have the correct symbol indices. */
3823 for (o = abfd->sections; o != NULL; o = o->next)
3824 {
3825 struct elf_link_hash_entry **rel_hash;
3826 Elf_Internal_Shdr *rel_hdr;
3827
3828 if ((o->flags & SEC_RELOC) == 0)
3829 continue;
3830
3831 rel_hash = elf_section_data (o)->rel_hashes;
3832 rel_hdr = &elf_section_data (o)->rel_hdr;
3833 for (i = 0; i < o->reloc_count; i++, rel_hash++)
3834 {
3835 if (*rel_hash == NULL)
3836 continue;
3837
3838 BFD_ASSERT ((*rel_hash)->indx >= 0);
3839
3840 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3841 {
3842 Elf_External_Rel *erel;
3843 Elf_Internal_Rel irel;
3844
3845 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3846 elf_swap_reloc_in (abfd, erel, &irel);
3847 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3848 ELF_R_TYPE (irel.r_info));
3849 elf_swap_reloc_out (abfd, &irel, erel);
3850 }
3851 else
3852 {
3853 Elf_External_Rela *erela;
3854 Elf_Internal_Rela irela;
3855
3856 BFD_ASSERT (rel_hdr->sh_entsize
3857 == sizeof (Elf_External_Rela));
3858
3859 erela = (Elf_External_Rela *) rel_hdr->contents + i;
3860 elf_swap_reloca_in (abfd, erela, &irela);
3861 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
3862 ELF_R_TYPE (irela.r_info));
3863 elf_swap_reloca_out (abfd, &irela, erela);
3864 }
3865 }
3866
3867 /* Set the reloc_count field to 0 to prevent write_relocs from
3868 trying to swap the relocs out itself. */
3869 o->reloc_count = 0;
3870 }
3871
3872 /* If we are linking against a dynamic object, or generating a
3873 shared library, finish up the dynamic linking information. */
3874 if (dynamic)
3875 {
3876 Elf_External_Dyn *dyncon, *dynconend;
3877
3878 /* Fix up .dynamic entries. */
3879 o = bfd_get_section_by_name (dynobj, ".dynamic");
3880 BFD_ASSERT (o != NULL);
3881
3882 dyncon = (Elf_External_Dyn *) o->contents;
3883 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
3884 for (; dyncon < dynconend; dyncon++)
3885 {
3886 Elf_Internal_Dyn dyn;
3887 const char *name;
3888 unsigned int type;
3889
3890 elf_swap_dyn_in (dynobj, dyncon, &dyn);
3891
3892 switch (dyn.d_tag)
3893 {
3894 default:
3895 break;
3896
3897 /* SVR4 linkers seem to set DT_INIT and DT_FINI based on
3898 magic _init and _fini symbols. This is pretty ugly,
3899 but we are compatible. */
3900 case DT_INIT:
3901 name = "_init";
3902 goto get_sym;
3903 case DT_FINI:
3904 name = "_fini";
3905 get_sym:
3906 {
3907 struct elf_link_hash_entry *h;
3908
3909 h = elf_link_hash_lookup (elf_hash_table (info), name,
3910 false, false, true);
3911 if (h != NULL
3912 && (h->root.type == bfd_link_hash_defined
3913 || h->root.type == bfd_link_hash_defweak))
3914 {
3915 dyn.d_un.d_val = h->root.u.def.value;
3916 o = h->root.u.def.section;
3917 if (o->output_section != NULL)
3918 dyn.d_un.d_val += (o->output_section->vma
3919 + o->output_offset);
3920 else
3921 {
3922 /* The symbol is imported from another shared
3923 library and does not apply to this one. */
3924 dyn.d_un.d_val = 0;
3925 }
3926
3927 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3928 }
3929 }
3930 break;
3931
3932 case DT_HASH:
3933 name = ".hash";
3934 goto get_vma;
3935 case DT_STRTAB:
3936 name = ".dynstr";
3937 goto get_vma;
3938 case DT_SYMTAB:
3939 name = ".dynsym";
3940 goto get_vma;
3941 case DT_VERDEF:
3942 name = ".gnu.version_d";
3943 goto get_vma;
3944 case DT_VERNEED:
3945 name = ".gnu.version_r";
3946 goto get_vma;
3947 case DT_VERSYM:
3948 name = ".gnu.version";
3949 get_vma:
3950 o = bfd_get_section_by_name (abfd, name);
3951 BFD_ASSERT (o != NULL);
3952 dyn.d_un.d_ptr = o->vma;
3953 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3954 break;
3955
3956 case DT_REL:
3957 case DT_RELA:
3958 case DT_RELSZ:
3959 case DT_RELASZ:
3960 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
3961 type = SHT_REL;
3962 else
3963 type = SHT_RELA;
3964 dyn.d_un.d_val = 0;
3965 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
3966 {
3967 Elf_Internal_Shdr *hdr;
3968
3969 hdr = elf_elfsections (abfd)[i];
3970 if (hdr->sh_type == type
3971 && (hdr->sh_flags & SHF_ALLOC) != 0)
3972 {
3973 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
3974 dyn.d_un.d_val += hdr->sh_size;
3975 else
3976 {
3977 if (dyn.d_un.d_val == 0
3978 || hdr->sh_addr < dyn.d_un.d_val)
3979 dyn.d_un.d_val = hdr->sh_addr;
3980 }
3981 }
3982 }
3983 elf_swap_dyn_out (dynobj, &dyn, dyncon);
3984 break;
3985 }
3986 }
3987 }
3988
3989 /* If we have created any dynamic sections, then output them. */
3990 if (dynobj != NULL)
3991 {
3992 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
3993 goto error_return;
3994
3995 for (o = dynobj->sections; o != NULL; o = o->next)
3996 {
3997 if ((o->flags & SEC_HAS_CONTENTS) == 0
3998 || o->_raw_size == 0)
3999 continue;
4000 if ((o->flags & SEC_LINKER_CREATED) == 0)
4001 {
4002 /* At this point, we are only interested in sections
4003 created by elf_link_create_dynamic_sections. */
4004 continue;
4005 }
4006 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4007 != SHT_STRTAB)
4008 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4009 {
4010 if (! bfd_set_section_contents (abfd, o->output_section,
4011 o->contents, o->output_offset,
4012 o->_raw_size))
4013 goto error_return;
4014 }
4015 else
4016 {
4017 file_ptr off;
4018
4019 /* The contents of the .dynstr section are actually in a
4020 stringtab. */
4021 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4022 if (bfd_seek (abfd, off, SEEK_SET) != 0
4023 || ! _bfd_stringtab_emit (abfd,
4024 elf_hash_table (info)->dynstr))
4025 goto error_return;
4026 }
4027 }
4028 }
4029
4030 /* If we have optimized stabs strings, output them. */
4031 if (elf_hash_table (info)->stab_info != NULL)
4032 {
4033 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4034 goto error_return;
4035 }
4036
4037 if (finfo.symstrtab != NULL)
4038 _bfd_stringtab_free (finfo.symstrtab);
4039 if (finfo.contents != NULL)
4040 free (finfo.contents);
4041 if (finfo.external_relocs != NULL)
4042 free (finfo.external_relocs);
4043 if (finfo.internal_relocs != NULL)
4044 free (finfo.internal_relocs);
4045 if (finfo.external_syms != NULL)
4046 free (finfo.external_syms);
4047 if (finfo.internal_syms != NULL)
4048 free (finfo.internal_syms);
4049 if (finfo.indices != NULL)
4050 free (finfo.indices);
4051 if (finfo.sections != NULL)
4052 free (finfo.sections);
4053 if (finfo.symbuf != NULL)
4054 free (finfo.symbuf);
4055 for (o = abfd->sections; o != NULL; o = o->next)
4056 {
4057 if ((o->flags & SEC_RELOC) != 0
4058 && elf_section_data (o)->rel_hashes != NULL)
4059 free (elf_section_data (o)->rel_hashes);
4060 }
4061
4062 elf_tdata (abfd)->linker = true;
4063
4064 return true;
4065
4066 error_return:
4067 if (finfo.symstrtab != NULL)
4068 _bfd_stringtab_free (finfo.symstrtab);
4069 if (finfo.contents != NULL)
4070 free (finfo.contents);
4071 if (finfo.external_relocs != NULL)
4072 free (finfo.external_relocs);
4073 if (finfo.internal_relocs != NULL)
4074 free (finfo.internal_relocs);
4075 if (finfo.external_syms != NULL)
4076 free (finfo.external_syms);
4077 if (finfo.internal_syms != NULL)
4078 free (finfo.internal_syms);
4079 if (finfo.indices != NULL)
4080 free (finfo.indices);
4081 if (finfo.sections != NULL)
4082 free (finfo.sections);
4083 if (finfo.symbuf != NULL)
4084 free (finfo.symbuf);
4085 for (o = abfd->sections; o != NULL; o = o->next)
4086 {
4087 if ((o->flags & SEC_RELOC) != 0
4088 && elf_section_data (o)->rel_hashes != NULL)
4089 free (elf_section_data (o)->rel_hashes);
4090 }
4091
4092 return false;
4093 }
4094
4095 /* Add a symbol to the output symbol table. */
4096
4097 static boolean
4098 elf_link_output_sym (finfo, name, elfsym, input_sec)
4099 struct elf_final_link_info *finfo;
4100 const char *name;
4101 Elf_Internal_Sym *elfsym;
4102 asection *input_sec;
4103 {
4104 boolean (*output_symbol_hook) PARAMS ((bfd *,
4105 struct bfd_link_info *info,
4106 const char *,
4107 Elf_Internal_Sym *,
4108 asection *));
4109
4110 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4111 elf_backend_link_output_symbol_hook;
4112 if (output_symbol_hook != NULL)
4113 {
4114 if (! ((*output_symbol_hook)
4115 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4116 return false;
4117 }
4118
4119 if (name == (const char *) NULL || *name == '\0')
4120 elfsym->st_name = 0;
4121 else
4122 {
4123 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4124 name, true,
4125 false);
4126 if (elfsym->st_name == (unsigned long) -1)
4127 return false;
4128 }
4129
4130 if (finfo->symbuf_count >= finfo->symbuf_size)
4131 {
4132 if (! elf_link_flush_output_syms (finfo))
4133 return false;
4134 }
4135
4136 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4137 (PTR) (finfo->symbuf + finfo->symbuf_count));
4138 ++finfo->symbuf_count;
4139
4140 ++finfo->output_bfd->symcount;
4141
4142 return true;
4143 }
4144
4145 /* Flush the output symbols to the file. */
4146
4147 static boolean
4148 elf_link_flush_output_syms (finfo)
4149 struct elf_final_link_info *finfo;
4150 {
4151 if (finfo->symbuf_count > 0)
4152 {
4153 Elf_Internal_Shdr *symtab;
4154
4155 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4156
4157 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4158 SEEK_SET) != 0
4159 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4160 sizeof (Elf_External_Sym), finfo->output_bfd)
4161 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4162 return false;
4163
4164 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4165
4166 finfo->symbuf_count = 0;
4167 }
4168
4169 return true;
4170 }
4171
4172 /* Add an external symbol to the symbol table. This is called from
4173 the hash table traversal routine. When generating a shared object,
4174 we go through the symbol table twice. The first time we output
4175 anything that might have been forced to local scope in a version
4176 script. The second time we output the symbols that are still
4177 global symbols. */
4178
4179 static boolean
4180 elf_link_output_extsym (h, data)
4181 struct elf_link_hash_entry *h;
4182 PTR data;
4183 {
4184 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4185 struct elf_final_link_info *finfo = eoinfo->finfo;
4186 boolean strip;
4187 Elf_Internal_Sym sym;
4188 asection *input_sec;
4189
4190 /* Decide whether to output this symbol in this pass. */
4191 if (eoinfo->localsyms)
4192 {
4193 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4194 return true;
4195 }
4196 else
4197 {
4198 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4199 return true;
4200 }
4201
4202 /* If we are not creating a shared library, and this symbol is
4203 referenced by a shared library but is not defined anywhere, then
4204 warn that it is undefined. If we do not do this, the runtime
4205 linker will complain that the symbol is undefined when the
4206 program is run. We don't have to worry about symbols that are
4207 referenced by regular files, because we will already have issued
4208 warnings for them. */
4209 if (! finfo->info->relocateable
4210 && ! finfo->info->shared
4211 && h->root.type == bfd_link_hash_undefined
4212 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4213 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4214 {
4215 if (! ((*finfo->info->callbacks->undefined_symbol)
4216 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4217 (asection *) NULL, 0)))
4218 {
4219 eoinfo->failed = true;
4220 return false;
4221 }
4222 }
4223
4224 /* We don't want to output symbols that have never been mentioned by
4225 a regular file, or that we have been told to strip. However, if
4226 h->indx is set to -2, the symbol is used by a reloc and we must
4227 output it. */
4228 if (h->indx == -2)
4229 strip = false;
4230 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4231 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4232 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4233 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4234 strip = true;
4235 else if (finfo->info->strip == strip_all
4236 || (finfo->info->strip == strip_some
4237 && bfd_hash_lookup (finfo->info->keep_hash,
4238 h->root.root.string,
4239 false, false) == NULL))
4240 strip = true;
4241 else
4242 strip = false;
4243
4244 /* If we're stripping it, and it's not a dynamic symbol, there's
4245 nothing else to do. */
4246 if (strip && h->dynindx == -1)
4247 return true;
4248
4249 sym.st_value = 0;
4250 sym.st_size = h->size;
4251 sym.st_other = h->other;
4252 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4253 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4254 else if (h->root.type == bfd_link_hash_undefweak
4255 || h->root.type == bfd_link_hash_defweak)
4256 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4257 else
4258 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4259
4260 switch (h->root.type)
4261 {
4262 default:
4263 case bfd_link_hash_new:
4264 abort ();
4265 return false;
4266
4267 case bfd_link_hash_undefined:
4268 input_sec = bfd_und_section_ptr;
4269 sym.st_shndx = SHN_UNDEF;
4270 break;
4271
4272 case bfd_link_hash_undefweak:
4273 input_sec = bfd_und_section_ptr;
4274 sym.st_shndx = SHN_UNDEF;
4275 break;
4276
4277 case bfd_link_hash_defined:
4278 case bfd_link_hash_defweak:
4279 {
4280 input_sec = h->root.u.def.section;
4281 if (input_sec->output_section != NULL)
4282 {
4283 sym.st_shndx =
4284 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4285 input_sec->output_section);
4286 if (sym.st_shndx == (unsigned short) -1)
4287 {
4288 eoinfo->failed = true;
4289 return false;
4290 }
4291
4292 /* ELF symbols in relocateable files are section relative,
4293 but in nonrelocateable files they are virtual
4294 addresses. */
4295 sym.st_value = h->root.u.def.value + input_sec->output_offset;
4296 if (! finfo->info->relocateable)
4297 sym.st_value += input_sec->output_section->vma;
4298 }
4299 else
4300 {
4301 BFD_ASSERT (input_sec->owner == NULL
4302 || (input_sec->owner->flags & DYNAMIC) != 0);
4303 sym.st_shndx = SHN_UNDEF;
4304 input_sec = bfd_und_section_ptr;
4305 }
4306 }
4307 break;
4308
4309 case bfd_link_hash_common:
4310 input_sec = h->root.u.c.p->section;
4311 sym.st_shndx = SHN_COMMON;
4312 sym.st_value = 1 << h->root.u.c.p->alignment_power;
4313 break;
4314
4315 case bfd_link_hash_indirect:
4316 /* These symbols are created by symbol versioning. They point
4317 to the decorated version of the name. For example, if the
4318 symbol foo@@GNU_1.2 is the default, which should be used when
4319 foo is used with no version, then we add an indirect symbol
4320 foo which points to foo@@GNU_1.2. We ignore these symbols,
4321 since the indirected symbol is already in the hash table. If
4322 the indirect symbol is non-ELF, fall through and output it. */
4323 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
4324 return true;
4325
4326 /* Fall through. */
4327 case bfd_link_hash_warning:
4328 /* We can't represent these symbols in ELF, although a warning
4329 symbol may have come from a .gnu.warning.SYMBOL section. We
4330 just put the target symbol in the hash table. If the target
4331 symbol does not really exist, don't do anything. */
4332 if (h->root.u.i.link->type == bfd_link_hash_new)
4333 return true;
4334 return (elf_link_output_extsym
4335 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
4336 }
4337
4338 /* Give the processor backend a chance to tweak the symbol value,
4339 and also to finish up anything that needs to be done for this
4340 symbol. */
4341 if ((h->dynindx != -1
4342 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4343 && elf_hash_table (finfo->info)->dynamic_sections_created)
4344 {
4345 struct elf_backend_data *bed;
4346
4347 bed = get_elf_backend_data (finfo->output_bfd);
4348 if (! ((*bed->elf_backend_finish_dynamic_symbol)
4349 (finfo->output_bfd, finfo->info, h, &sym)))
4350 {
4351 eoinfo->failed = true;
4352 return false;
4353 }
4354 }
4355
4356 /* If this symbol should be put in the .dynsym section, then put it
4357 there now. We have already know the symbol index. We also fill
4358 in the entry in the .hash section. */
4359 if (h->dynindx != -1
4360 && elf_hash_table (finfo->info)->dynamic_sections_created)
4361 {
4362 char *p, *copy;
4363 const char *name;
4364 size_t bucketcount;
4365 size_t bucket;
4366 bfd_byte *bucketpos;
4367 bfd_vma chain;
4368
4369 sym.st_name = h->dynstr_index;
4370
4371 elf_swap_symbol_out (finfo->output_bfd, &sym,
4372 (PTR) (((Elf_External_Sym *)
4373 finfo->dynsym_sec->contents)
4374 + h->dynindx));
4375
4376 /* We didn't include the version string in the dynamic string
4377 table, so we must not consider it in the hash table. */
4378 name = h->root.root.string;
4379 p = strchr (name, ELF_VER_CHR);
4380 if (p == NULL)
4381 copy = NULL;
4382 else
4383 {
4384 copy = bfd_alloc (finfo->output_bfd, p - name + 1);
4385 strncpy (copy, name, p - name);
4386 copy[p - name] = '\0';
4387 name = copy;
4388 }
4389
4390 bucketcount = elf_hash_table (finfo->info)->bucketcount;
4391 bucket = bfd_elf_hash ((const unsigned char *) name) % bucketcount;
4392 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
4393 + (bucket + 2) * (ARCH_SIZE / 8));
4394 chain = get_word (finfo->output_bfd, bucketpos);
4395 put_word (finfo->output_bfd, h->dynindx, bucketpos);
4396 put_word (finfo->output_bfd, chain,
4397 ((bfd_byte *) finfo->hash_sec->contents
4398 + (bucketcount + 2 + h->dynindx) * (ARCH_SIZE / 8)));
4399
4400 if (copy != NULL)
4401 bfd_release (finfo->output_bfd, copy);
4402
4403 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
4404 {
4405 Elf_Internal_Versym iversym;
4406
4407 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
4408 {
4409 if (h->verinfo.verdef == NULL)
4410 iversym.vs_vers = 0;
4411 else
4412 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
4413 }
4414 else
4415 {
4416 if (h->verinfo.vertree == NULL)
4417 iversym.vs_vers = 1;
4418 else
4419 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
4420 }
4421
4422 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
4423 iversym.vs_vers |= VERSYM_HIDDEN;
4424
4425 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
4426 (((Elf_External_Versym *)
4427 finfo->symver_sec->contents)
4428 + h->dynindx));
4429 }
4430 }
4431
4432 /* If we're stripping it, then it was just a dynamic symbol, and
4433 there's nothing else to do. */
4434 if (strip)
4435 return true;
4436
4437 h->indx = finfo->output_bfd->symcount;
4438
4439 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
4440 {
4441 eoinfo->failed = true;
4442 return false;
4443 }
4444
4445 return true;
4446 }
4447
4448 /* Link an input file into the linker output file. This function
4449 handles all the sections and relocations of the input file at once.
4450 This is so that we only have to read the local symbols once, and
4451 don't have to keep them in memory. */
4452
4453 static boolean
4454 elf_link_input_bfd (finfo, input_bfd)
4455 struct elf_final_link_info *finfo;
4456 bfd *input_bfd;
4457 {
4458 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
4459 bfd *, asection *, bfd_byte *,
4460 Elf_Internal_Rela *,
4461 Elf_Internal_Sym *, asection **));
4462 bfd *output_bfd;
4463 Elf_Internal_Shdr *symtab_hdr;
4464 size_t locsymcount;
4465 size_t extsymoff;
4466 Elf_External_Sym *external_syms;
4467 Elf_External_Sym *esym;
4468 Elf_External_Sym *esymend;
4469 Elf_Internal_Sym *isym;
4470 long *pindex;
4471 asection **ppsection;
4472 asection *o;
4473
4474 output_bfd = finfo->output_bfd;
4475 relocate_section =
4476 get_elf_backend_data (output_bfd)->elf_backend_relocate_section;
4477
4478 /* If this is a dynamic object, we don't want to do anything here:
4479 we don't want the local symbols, and we don't want the section
4480 contents. */
4481 if ((input_bfd->flags & DYNAMIC) != 0)
4482 return true;
4483
4484 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
4485 if (elf_bad_symtab (input_bfd))
4486 {
4487 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
4488 extsymoff = 0;
4489 }
4490 else
4491 {
4492 locsymcount = symtab_hdr->sh_info;
4493 extsymoff = symtab_hdr->sh_info;
4494 }
4495
4496 /* Read the local symbols. */
4497 if (symtab_hdr->contents != NULL)
4498 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
4499 else if (locsymcount == 0)
4500 external_syms = NULL;
4501 else
4502 {
4503 external_syms = finfo->external_syms;
4504 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
4505 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
4506 locsymcount, input_bfd)
4507 != locsymcount * sizeof (Elf_External_Sym)))
4508 return false;
4509 }
4510
4511 /* Swap in the local symbols and write out the ones which we know
4512 are going into the output file. */
4513 esym = external_syms;
4514 esymend = esym + locsymcount;
4515 isym = finfo->internal_syms;
4516 pindex = finfo->indices;
4517 ppsection = finfo->sections;
4518 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
4519 {
4520 asection *isec;
4521 const char *name;
4522 Elf_Internal_Sym osym;
4523
4524 elf_swap_symbol_in (input_bfd, esym, isym);
4525 *pindex = -1;
4526
4527 if (elf_bad_symtab (input_bfd))
4528 {
4529 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
4530 {
4531 *ppsection = NULL;
4532 continue;
4533 }
4534 }
4535
4536 if (isym->st_shndx == SHN_UNDEF)
4537 isec = bfd_und_section_ptr;
4538 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
4539 isec = section_from_elf_index (input_bfd, isym->st_shndx);
4540 else if (isym->st_shndx == SHN_ABS)
4541 isec = bfd_abs_section_ptr;
4542 else if (isym->st_shndx == SHN_COMMON)
4543 isec = bfd_com_section_ptr;
4544 else
4545 {
4546 /* Who knows? */
4547 isec = NULL;
4548 }
4549
4550 *ppsection = isec;
4551
4552 /* Don't output the first, undefined, symbol. */
4553 if (esym == external_syms)
4554 continue;
4555
4556 /* If we are stripping all symbols, we don't want to output this
4557 one. */
4558 if (finfo->info->strip == strip_all)
4559 continue;
4560
4561 /* We never output section symbols. Instead, we use the section
4562 symbol of the corresponding section in the output file. */
4563 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
4564 continue;
4565
4566 /* If we are discarding all local symbols, we don't want to
4567 output this one. If we are generating a relocateable output
4568 file, then some of the local symbols may be required by
4569 relocs; we output them below as we discover that they are
4570 needed. */
4571 if (finfo->info->discard == discard_all)
4572 continue;
4573
4574 /* If this symbol is defined in a section which we are
4575 discarding, we don't need to keep it, but note that
4576 linker_mark is only reliable for sections that have contents.
4577 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
4578 as well as linker_mark. */
4579 if (isym->st_shndx > 0
4580 && isym->st_shndx < SHN_LORESERVE
4581 && isec != NULL
4582 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
4583 || (! finfo->info->relocateable
4584 && (isec->flags & SEC_EXCLUDE) != 0)))
4585 continue;
4586
4587 /* Get the name of the symbol. */
4588 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
4589 isym->st_name);
4590 if (name == NULL)
4591 return false;
4592
4593 /* See if we are discarding symbols with this name. */
4594 if ((finfo->info->strip == strip_some
4595 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
4596 == NULL))
4597 || (finfo->info->discard == discard_l
4598 && bfd_is_local_label_name (input_bfd, name)))
4599 continue;
4600
4601 /* If we get here, we are going to output this symbol. */
4602
4603 osym = *isym;
4604
4605 /* Adjust the section index for the output file. */
4606 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
4607 isec->output_section);
4608 if (osym.st_shndx == (unsigned short) -1)
4609 return false;
4610
4611 *pindex = output_bfd->symcount;
4612
4613 /* ELF symbols in relocateable files are section relative, but
4614 in executable files they are virtual addresses. Note that
4615 this code assumes that all ELF sections have an associated
4616 BFD section with a reasonable value for output_offset; below
4617 we assume that they also have a reasonable value for
4618 output_section. Any special sections must be set up to meet
4619 these requirements. */
4620 osym.st_value += isec->output_offset;
4621 if (! finfo->info->relocateable)
4622 osym.st_value += isec->output_section->vma;
4623
4624 if (! elf_link_output_sym (finfo, name, &osym, isec))
4625 return false;
4626 }
4627
4628 /* Relocate the contents of each section. */
4629 for (o = input_bfd->sections; o != NULL; o = o->next)
4630 {
4631 bfd_byte *contents;
4632
4633 if (! o->linker_mark)
4634 {
4635 /* This section was omitted from the link. */
4636 continue;
4637 }
4638
4639 if ((o->flags & SEC_HAS_CONTENTS) == 0
4640 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
4641 continue;
4642
4643 if ((o->flags & SEC_LINKER_CREATED) != 0)
4644 {
4645 /* Section was created by elf_link_create_dynamic_sections
4646 or somesuch. */
4647 continue;
4648 }
4649
4650 /* Get the contents of the section. They have been cached by a
4651 relaxation routine. Note that o is a section in an input
4652 file, so the contents field will not have been set by any of
4653 the routines which work on output files. */
4654 if (elf_section_data (o)->this_hdr.contents != NULL)
4655 contents = elf_section_data (o)->this_hdr.contents;
4656 else
4657 {
4658 contents = finfo->contents;
4659 if (! bfd_get_section_contents (input_bfd, o, contents,
4660 (file_ptr) 0, o->_raw_size))
4661 return false;
4662 }
4663
4664 if ((o->flags & SEC_RELOC) != 0)
4665 {
4666 Elf_Internal_Rela *internal_relocs;
4667
4668 /* Get the swapped relocs. */
4669 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
4670 (input_bfd, o, finfo->external_relocs,
4671 finfo->internal_relocs, false));
4672 if (internal_relocs == NULL
4673 && o->reloc_count > 0)
4674 return false;
4675
4676 /* Relocate the section by invoking a back end routine.
4677
4678 The back end routine is responsible for adjusting the
4679 section contents as necessary, and (if using Rela relocs
4680 and generating a relocateable output file) adjusting the
4681 reloc addend as necessary.
4682
4683 The back end routine does not have to worry about setting
4684 the reloc address or the reloc symbol index.
4685
4686 The back end routine is given a pointer to the swapped in
4687 internal symbols, and can access the hash table entries
4688 for the external symbols via elf_sym_hashes (input_bfd).
4689
4690 When generating relocateable output, the back end routine
4691 must handle STB_LOCAL/STT_SECTION symbols specially. The
4692 output symbol is going to be a section symbol
4693 corresponding to the output section, which will require
4694 the addend to be adjusted. */
4695
4696 if (! (*relocate_section) (output_bfd, finfo->info,
4697 input_bfd, o, contents,
4698 internal_relocs,
4699 finfo->internal_syms,
4700 finfo->sections))
4701 return false;
4702
4703 if (finfo->info->relocateable)
4704 {
4705 Elf_Internal_Rela *irela;
4706 Elf_Internal_Rela *irelaend;
4707 struct elf_link_hash_entry **rel_hash;
4708 Elf_Internal_Shdr *input_rel_hdr;
4709 Elf_Internal_Shdr *output_rel_hdr;
4710
4711 /* Adjust the reloc addresses and symbol indices. */
4712
4713 irela = internal_relocs;
4714 irelaend = irela + o->reloc_count;
4715 rel_hash = (elf_section_data (o->output_section)->rel_hashes
4716 + o->output_section->reloc_count);
4717 for (; irela < irelaend; irela++, rel_hash++)
4718 {
4719 unsigned long r_symndx;
4720 Elf_Internal_Sym *isym;
4721 asection *sec;
4722
4723 irela->r_offset += o->output_offset;
4724
4725 r_symndx = ELF_R_SYM (irela->r_info);
4726
4727 if (r_symndx == 0)
4728 continue;
4729
4730 if (r_symndx >= locsymcount
4731 || (elf_bad_symtab (input_bfd)
4732 && finfo->sections[r_symndx] == NULL))
4733 {
4734 struct elf_link_hash_entry *rh;
4735 long indx;
4736
4737 /* This is a reloc against a global symbol. We
4738 have not yet output all the local symbols, so
4739 we do not know the symbol index of any global
4740 symbol. We set the rel_hash entry for this
4741 reloc to point to the global hash table entry
4742 for this symbol. The symbol index is then
4743 set at the end of elf_bfd_final_link. */
4744 indx = r_symndx - extsymoff;
4745 rh = elf_sym_hashes (input_bfd)[indx];
4746 while (rh->root.type == bfd_link_hash_indirect
4747 || rh->root.type == bfd_link_hash_warning)
4748 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
4749
4750 /* Setting the index to -2 tells
4751 elf_link_output_extsym that this symbol is
4752 used by a reloc. */
4753 BFD_ASSERT (rh->indx < 0);
4754 rh->indx = -2;
4755
4756 *rel_hash = rh;
4757
4758 continue;
4759 }
4760
4761 /* This is a reloc against a local symbol. */
4762
4763 *rel_hash = NULL;
4764 isym = finfo->internal_syms + r_symndx;
4765 sec = finfo->sections[r_symndx];
4766 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
4767 {
4768 /* I suppose the backend ought to fill in the
4769 section of any STT_SECTION symbol against a
4770 processor specific section. If we have
4771 discarded a section, the output_section will
4772 be the absolute section. */
4773 if (sec != NULL
4774 && (bfd_is_abs_section (sec)
4775 || (sec->output_section != NULL
4776 && bfd_is_abs_section (sec->output_section))))
4777 r_symndx = 0;
4778 else if (sec == NULL || sec->owner == NULL)
4779 {
4780 bfd_set_error (bfd_error_bad_value);
4781 return false;
4782 }
4783 else
4784 {
4785 r_symndx = sec->output_section->target_index;
4786 BFD_ASSERT (r_symndx != 0);
4787 }
4788 }
4789 else
4790 {
4791 if (finfo->indices[r_symndx] == -1)
4792 {
4793 unsigned long link;
4794 const char *name;
4795 asection *osec;
4796
4797 if (finfo->info->strip == strip_all)
4798 {
4799 /* You can't do ld -r -s. */
4800 bfd_set_error (bfd_error_invalid_operation);
4801 return false;
4802 }
4803
4804 /* This symbol was skipped earlier, but
4805 since it is needed by a reloc, we
4806 must output it now. */
4807 link = symtab_hdr->sh_link;
4808 name = bfd_elf_string_from_elf_section (input_bfd,
4809 link,
4810 isym->st_name);
4811 if (name == NULL)
4812 return false;
4813
4814 osec = sec->output_section;
4815 isym->st_shndx =
4816 _bfd_elf_section_from_bfd_section (output_bfd,
4817 osec);
4818 if (isym->st_shndx == (unsigned short) -1)
4819 return false;
4820
4821 isym->st_value += sec->output_offset;
4822 if (! finfo->info->relocateable)
4823 isym->st_value += osec->vma;
4824
4825 finfo->indices[r_symndx] = output_bfd->symcount;
4826
4827 if (! elf_link_output_sym (finfo, name, isym, sec))
4828 return false;
4829 }
4830
4831 r_symndx = finfo->indices[r_symndx];
4832 }
4833
4834 irela->r_info = ELF_R_INFO (r_symndx,
4835 ELF_R_TYPE (irela->r_info));
4836 }
4837
4838 /* Swap out the relocs. */
4839 input_rel_hdr = &elf_section_data (o)->rel_hdr;
4840 output_rel_hdr = &elf_section_data (o->output_section)->rel_hdr;
4841 BFD_ASSERT (output_rel_hdr->sh_entsize
4842 == input_rel_hdr->sh_entsize);
4843 irela = internal_relocs;
4844 irelaend = irela + o->reloc_count;
4845 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4846 {
4847 Elf_External_Rel *erel;
4848
4849 erel = ((Elf_External_Rel *) output_rel_hdr->contents
4850 + o->output_section->reloc_count);
4851 for (; irela < irelaend; irela++, erel++)
4852 {
4853 Elf_Internal_Rel irel;
4854
4855 irel.r_offset = irela->r_offset;
4856 irel.r_info = irela->r_info;
4857 BFD_ASSERT (irela->r_addend == 0);
4858 elf_swap_reloc_out (output_bfd, &irel, erel);
4859 }
4860 }
4861 else
4862 {
4863 Elf_External_Rela *erela;
4864
4865 BFD_ASSERT (input_rel_hdr->sh_entsize
4866 == sizeof (Elf_External_Rela));
4867 erela = ((Elf_External_Rela *) output_rel_hdr->contents
4868 + o->output_section->reloc_count);
4869 for (; irela < irelaend; irela++, erela++)
4870 elf_swap_reloca_out (output_bfd, irela, erela);
4871 }
4872
4873 o->output_section->reloc_count += o->reloc_count;
4874 }
4875 }
4876
4877 /* Write out the modified section contents. */
4878 if (elf_section_data (o)->stab_info == NULL)
4879 {
4880 if (! bfd_set_section_contents (output_bfd, o->output_section,
4881 contents, o->output_offset,
4882 (o->_cooked_size != 0
4883 ? o->_cooked_size
4884 : o->_raw_size)))
4885 return false;
4886 }
4887 else
4888 {
4889 if (! (_bfd_write_section_stabs
4890 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
4891 o, &elf_section_data (o)->stab_info, contents)))
4892 return false;
4893 }
4894 }
4895
4896 return true;
4897 }
4898
4899 /* Generate a reloc when linking an ELF file. This is a reloc
4900 requested by the linker, and does come from any input file. This
4901 is used to build constructor and destructor tables when linking
4902 with -Ur. */
4903
4904 static boolean
4905 elf_reloc_link_order (output_bfd, info, output_section, link_order)
4906 bfd *output_bfd;
4907 struct bfd_link_info *info;
4908 asection *output_section;
4909 struct bfd_link_order *link_order;
4910 {
4911 reloc_howto_type *howto;
4912 long indx;
4913 bfd_vma offset;
4914 bfd_vma addend;
4915 struct elf_link_hash_entry **rel_hash_ptr;
4916 Elf_Internal_Shdr *rel_hdr;
4917
4918 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
4919 if (howto == NULL)
4920 {
4921 bfd_set_error (bfd_error_bad_value);
4922 return false;
4923 }
4924
4925 addend = link_order->u.reloc.p->addend;
4926
4927 /* Figure out the symbol index. */
4928 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
4929 + output_section->reloc_count);
4930 if (link_order->type == bfd_section_reloc_link_order)
4931 {
4932 indx = link_order->u.reloc.p->u.section->target_index;
4933 BFD_ASSERT (indx != 0);
4934 *rel_hash_ptr = NULL;
4935 }
4936 else
4937 {
4938 struct elf_link_hash_entry *h;
4939
4940 /* Treat a reloc against a defined symbol as though it were
4941 actually against the section. */
4942 h = ((struct elf_link_hash_entry *)
4943 bfd_wrapped_link_hash_lookup (output_bfd, info,
4944 link_order->u.reloc.p->u.name,
4945 false, false, true));
4946 if (h != NULL
4947 && (h->root.type == bfd_link_hash_defined
4948 || h->root.type == bfd_link_hash_defweak))
4949 {
4950 asection *section;
4951
4952 section = h->root.u.def.section;
4953 indx = section->output_section->target_index;
4954 *rel_hash_ptr = NULL;
4955 /* It seems that we ought to add the symbol value to the
4956 addend here, but in practice it has already been added
4957 because it was passed to constructor_callback. */
4958 addend += section->output_section->vma + section->output_offset;
4959 }
4960 else if (h != NULL)
4961 {
4962 /* Setting the index to -2 tells elf_link_output_extsym that
4963 this symbol is used by a reloc. */
4964 h->indx = -2;
4965 *rel_hash_ptr = h;
4966 indx = 0;
4967 }
4968 else
4969 {
4970 if (! ((*info->callbacks->unattached_reloc)
4971 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
4972 (asection *) NULL, (bfd_vma) 0)))
4973 return false;
4974 indx = 0;
4975 }
4976 }
4977
4978 /* If this is an inplace reloc, we must write the addend into the
4979 object file. */
4980 if (howto->partial_inplace && addend != 0)
4981 {
4982 bfd_size_type size;
4983 bfd_reloc_status_type rstat;
4984 bfd_byte *buf;
4985 boolean ok;
4986
4987 size = bfd_get_reloc_size (howto);
4988 buf = (bfd_byte *) bfd_zmalloc (size);
4989 if (buf == (bfd_byte *) NULL)
4990 return false;
4991 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
4992 switch (rstat)
4993 {
4994 case bfd_reloc_ok:
4995 break;
4996 default:
4997 case bfd_reloc_outofrange:
4998 abort ();
4999 case bfd_reloc_overflow:
5000 if (! ((*info->callbacks->reloc_overflow)
5001 (info,
5002 (link_order->type == bfd_section_reloc_link_order
5003 ? bfd_section_name (output_bfd,
5004 link_order->u.reloc.p->u.section)
5005 : link_order->u.reloc.p->u.name),
5006 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5007 (bfd_vma) 0)))
5008 {
5009 free (buf);
5010 return false;
5011 }
5012 break;
5013 }
5014 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5015 (file_ptr) link_order->offset, size);
5016 free (buf);
5017 if (! ok)
5018 return false;
5019 }
5020
5021 /* The address of a reloc is relative to the section in a
5022 relocateable file, and is a virtual address in an executable
5023 file. */
5024 offset = link_order->offset;
5025 if (! info->relocateable)
5026 offset += output_section->vma;
5027
5028 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5029
5030 if (rel_hdr->sh_type == SHT_REL)
5031 {
5032 Elf_Internal_Rel irel;
5033 Elf_External_Rel *erel;
5034
5035 irel.r_offset = offset;
5036 irel.r_info = ELF_R_INFO (indx, howto->type);
5037 erel = ((Elf_External_Rel *) rel_hdr->contents
5038 + output_section->reloc_count);
5039 elf_swap_reloc_out (output_bfd, &irel, erel);
5040 }
5041 else
5042 {
5043 Elf_Internal_Rela irela;
5044 Elf_External_Rela *erela;
5045
5046 irela.r_offset = offset;
5047 irela.r_info = ELF_R_INFO (indx, howto->type);
5048 irela.r_addend = addend;
5049 erela = ((Elf_External_Rela *) rel_hdr->contents
5050 + output_section->reloc_count);
5051 elf_swap_reloca_out (output_bfd, &irela, erela);
5052 }
5053
5054 ++output_section->reloc_count;
5055
5056 return true;
5057 }
5058
5059 \f
5060 /* Allocate a pointer to live in a linker created section. */
5061
5062 boolean
5063 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5064 bfd *abfd;
5065 struct bfd_link_info *info;
5066 elf_linker_section_t *lsect;
5067 struct elf_link_hash_entry *h;
5068 const Elf_Internal_Rela *rel;
5069 {
5070 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5071 elf_linker_section_pointers_t *linker_section_ptr;
5072 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5073
5074 BFD_ASSERT (lsect != NULL);
5075
5076 /* Is this a global symbol? */
5077 if (h != NULL)
5078 {
5079 /* Has this symbol already been allocated, if so, our work is done */
5080 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5081 rel->r_addend,
5082 lsect->which))
5083 return true;
5084
5085 ptr_linker_section_ptr = &h->linker_section_pointer;
5086 /* Make sure this symbol is output as a dynamic symbol. */
5087 if (h->dynindx == -1)
5088 {
5089 if (! elf_link_record_dynamic_symbol (info, h))
5090 return false;
5091 }
5092
5093 if (lsect->rel_section)
5094 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5095 }
5096
5097 else /* Allocation of a pointer to a local symbol */
5098 {
5099 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5100
5101 /* Allocate a table to hold the local symbols if first time */
5102 if (!ptr)
5103 {
5104 int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5105 register unsigned int i;
5106
5107 ptr = (elf_linker_section_pointers_t **)
5108 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5109
5110 if (!ptr)
5111 return false;
5112
5113 elf_local_ptr_offsets (abfd) = ptr;
5114 for (i = 0; i < num_symbols; i++)
5115 ptr[i] = (elf_linker_section_pointers_t *)0;
5116 }
5117
5118 /* Has this symbol already been allocated, if so, our work is done */
5119 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5120 rel->r_addend,
5121 lsect->which))
5122 return true;
5123
5124 ptr_linker_section_ptr = &ptr[r_symndx];
5125
5126 if (info->shared)
5127 {
5128 /* If we are generating a shared object, we need to
5129 output a R_<xxx>_RELATIVE reloc so that the
5130 dynamic linker can adjust this GOT entry. */
5131 BFD_ASSERT (lsect->rel_section != NULL);
5132 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5133 }
5134 }
5135
5136 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5137 from internal memory. */
5138 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5139 linker_section_ptr = (elf_linker_section_pointers_t *)
5140 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5141
5142 if (!linker_section_ptr)
5143 return false;
5144
5145 linker_section_ptr->next = *ptr_linker_section_ptr;
5146 linker_section_ptr->addend = rel->r_addend;
5147 linker_section_ptr->which = lsect->which;
5148 linker_section_ptr->written_address_p = false;
5149 *ptr_linker_section_ptr = linker_section_ptr;
5150
5151 #if 0
5152 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5153 {
5154 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5155 lsect->hole_offset += ARCH_SIZE / 8;
5156 lsect->sym_offset += ARCH_SIZE / 8;
5157 if (lsect->sym_hash) /* Bump up symbol value if needed */
5158 {
5159 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5160 #ifdef DEBUG
5161 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5162 lsect->sym_hash->root.root.string,
5163 (long)ARCH_SIZE / 8,
5164 (long)lsect->sym_hash->root.u.def.value);
5165 #endif
5166 }
5167 }
5168 else
5169 #endif
5170 linker_section_ptr->offset = lsect->section->_raw_size;
5171
5172 lsect->section->_raw_size += ARCH_SIZE / 8;
5173
5174 #ifdef DEBUG
5175 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5176 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5177 #endif
5178
5179 return true;
5180 }
5181
5182 \f
5183 #if ARCH_SIZE==64
5184 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5185 #endif
5186 #if ARCH_SIZE==32
5187 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5188 #endif
5189
5190 /* Fill in the address for a pointer generated in alinker section. */
5191
5192 bfd_vma
5193 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5194 bfd *output_bfd;
5195 bfd *input_bfd;
5196 struct bfd_link_info *info;
5197 elf_linker_section_t *lsect;
5198 struct elf_link_hash_entry *h;
5199 bfd_vma relocation;
5200 const Elf_Internal_Rela *rel;
5201 int relative_reloc;
5202 {
5203 elf_linker_section_pointers_t *linker_section_ptr;
5204
5205 BFD_ASSERT (lsect != NULL);
5206
5207 if (h != NULL) /* global symbol */
5208 {
5209 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5210 rel->r_addend,
5211 lsect->which);
5212
5213 BFD_ASSERT (linker_section_ptr != NULL);
5214
5215 if (! elf_hash_table (info)->dynamic_sections_created
5216 || (info->shared
5217 && info->symbolic
5218 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5219 {
5220 /* This is actually a static link, or it is a
5221 -Bsymbolic link and the symbol is defined
5222 locally. We must initialize this entry in the
5223 global section.
5224
5225 When doing a dynamic link, we create a .rela.<xxx>
5226 relocation entry to initialize the value. This
5227 is done in the finish_dynamic_symbol routine. */
5228 if (!linker_section_ptr->written_address_p)
5229 {
5230 linker_section_ptr->written_address_p = true;
5231 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5232 lsect->section->contents + linker_section_ptr->offset);
5233 }
5234 }
5235 }
5236 else /* local symbol */
5237 {
5238 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
5239 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
5240 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
5241 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
5242 rel->r_addend,
5243 lsect->which);
5244
5245 BFD_ASSERT (linker_section_ptr != NULL);
5246
5247 /* Write out pointer if it hasn't been rewritten out before */
5248 if (!linker_section_ptr->written_address_p)
5249 {
5250 linker_section_ptr->written_address_p = true;
5251 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5252 lsect->section->contents + linker_section_ptr->offset);
5253
5254 if (info->shared)
5255 {
5256 asection *srel = lsect->rel_section;
5257 Elf_Internal_Rela outrel;
5258
5259 /* We need to generate a relative reloc for the dynamic linker. */
5260 if (!srel)
5261 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
5262 lsect->rel_name);
5263
5264 BFD_ASSERT (srel != NULL);
5265
5266 outrel.r_offset = (lsect->section->output_section->vma
5267 + lsect->section->output_offset
5268 + linker_section_ptr->offset);
5269 outrel.r_info = ELF_R_INFO (0, relative_reloc);
5270 outrel.r_addend = 0;
5271 elf_swap_reloca_out (output_bfd, &outrel,
5272 (((Elf_External_Rela *)
5273 lsect->section->contents)
5274 + lsect->section->reloc_count));
5275 ++lsect->section->reloc_count;
5276 }
5277 }
5278 }
5279
5280 relocation = (lsect->section->output_offset
5281 + linker_section_ptr->offset
5282 - lsect->hole_offset
5283 - lsect->sym_offset);
5284
5285 #ifdef DEBUG
5286 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
5287 lsect->name, (long)relocation, (long)relocation);
5288 #endif
5289
5290 /* Subtract out the addend, because it will get added back in by the normal
5291 processing. */
5292 return relocation - linker_section_ptr->addend;
5293 }