1999-09-12 Donn Terry <donn@interix.com>
[binutils.git] / bfd / elflink.h
blob6196014dd3b7a8101fda29cde3fdafd1869afc39
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
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.
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.
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. */
20 /* ELF linker code. */
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
25 struct elf_info_failed
27 boolean failed;
28 struct bfd_link_info *info;
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_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
71 switch (bfd_get_format (abfd))
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
84 /* Add symbols from an ELF archive file to the linker hash table. We
85 don't use _bfd_generic_link_add_archive_symbols because of a
86 problem which arises on UnixWare. The UnixWare libc.so is an
87 archive which includes an entry libc.so.1 which defines a bunch of
88 symbols. The libc.so archive also includes a number of other
89 object files, which also define symbols, some of which are the same
90 as those defined in libc.so.1. Correct linking requires that we
91 consider each object file in turn, and include it if it defines any
92 symbols we need. _bfd_generic_link_add_archive_symbols does not do
93 this; it looks through the list of undefined symbols, and includes
94 any object file which defines them. When this algorithm is used on
95 UnixWare, it winds up pulling in libc.so.1 early and defining a
96 bunch of symbols. This means that some of the other objects in the
97 archive are not included in the link, which is incorrect since they
98 precede libc.so.1 in the archive.
100 Fortunately, ELF archive handling is simpler than that done by
101 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
102 oddities. In ELF, if we find a symbol in the archive map, and the
103 symbol is currently undefined, we know that we must pull in that
104 object file.
106 Unfortunately, we do have to make multiple passes over the symbol
107 table until nothing further is resolved. */
109 static boolean
110 elf_link_add_archive_symbols (abfd, info)
111 bfd *abfd;
112 struct bfd_link_info *info;
114 symindex c;
115 boolean *defined = NULL;
116 boolean *included = NULL;
117 carsym *symdefs;
118 boolean loop;
120 if (! bfd_has_map (abfd))
122 /* An empty archive is a special case. */
123 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
124 return true;
125 bfd_set_error (bfd_error_no_armap);
126 return false;
129 /* Keep track of all symbols we know to be already defined, and all
130 files we know to be already included. This is to speed up the
131 second and subsequent passes. */
132 c = bfd_ardata (abfd)->symdef_count;
133 if (c == 0)
134 return true;
135 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
136 included = (boolean *) bfd_malloc (c * sizeof (boolean));
137 if (defined == (boolean *) NULL || included == (boolean *) NULL)
138 goto error_return;
139 memset (defined, 0, c * sizeof (boolean));
140 memset (included, 0, c * sizeof (boolean));
142 symdefs = bfd_ardata (abfd)->symdefs;
146 file_ptr last;
147 symindex i;
148 carsym *symdef;
149 carsym *symdefend;
151 loop = false;
152 last = -1;
154 symdef = symdefs;
155 symdefend = symdef + c;
156 for (i = 0; symdef < symdefend; symdef++, i++)
158 struct elf_link_hash_entry *h;
159 bfd *element;
160 struct bfd_link_hash_entry *undefs_tail;
161 symindex mark;
163 if (defined[i] || included[i])
164 continue;
165 if (symdef->file_offset == last)
167 included[i] = true;
168 continue;
171 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
172 false, false, false);
174 if (h == NULL)
176 char *p, *copy;
178 /* If this is a default version (the name contains @@),
179 look up the symbol again without the version. The
180 effect is that references to the symbol without the
181 version will be matched by the default symbol in the
182 archive. */
184 p = strchr (symdef->name, ELF_VER_CHR);
185 if (p == NULL || p[1] != ELF_VER_CHR)
186 continue;
188 copy = bfd_alloc (abfd, p - symdef->name + 1);
189 if (copy == NULL)
190 goto error_return;
191 memcpy (copy, symdef->name, p - symdef->name);
192 copy[p - symdef->name] = '\0';
194 h = elf_link_hash_lookup (elf_hash_table (info), copy,
195 false, false, false);
197 bfd_release (abfd, copy);
200 if (h == NULL)
201 continue;
203 if (h->root.type != bfd_link_hash_undefined)
205 if (h->root.type != bfd_link_hash_undefweak)
206 defined[i] = true;
207 continue;
210 /* We need to include this archive member. */
212 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
213 if (element == (bfd *) NULL)
214 goto error_return;
216 if (! bfd_check_format (element, bfd_object))
217 goto error_return;
219 /* Doublecheck that we have not included this object
220 already--it should be impossible, but there may be
221 something wrong with the archive. */
222 if (element->archive_pass != 0)
224 bfd_set_error (bfd_error_bad_value);
225 goto error_return;
227 element->archive_pass = 1;
229 undefs_tail = info->hash->undefs_tail;
231 if (! (*info->callbacks->add_archive_element) (info, element,
232 symdef->name))
233 goto error_return;
234 if (! elf_link_add_object_symbols (element, info))
235 goto error_return;
237 /* If there are any new undefined symbols, we need to make
238 another pass through the archive in order to see whether
239 they can be defined. FIXME: This isn't perfect, because
240 common symbols wind up on undefs_tail and because an
241 undefined symbol which is defined later on in this pass
242 does not require another pass. This isn't a bug, but it
243 does make the code less efficient than it could be. */
244 if (undefs_tail != info->hash->undefs_tail)
245 loop = true;
247 /* Look backward to mark all symbols from this object file
248 which we have already seen in this pass. */
249 mark = i;
252 included[mark] = true;
253 if (mark == 0)
254 break;
255 --mark;
257 while (symdefs[mark].file_offset == symdef->file_offset);
259 /* We mark subsequent symbols from this object file as we go
260 on through the loop. */
261 last = symdef->file_offset;
264 while (loop);
266 free (defined);
267 free (included);
269 return true;
271 error_return:
272 if (defined != (boolean *) NULL)
273 free (defined);
274 if (included != (boolean *) NULL)
275 free (included);
276 return false;
279 /* This function is called when we want to define a new symbol. It
280 handles the various cases which arise when we find a definition in
281 a dynamic object, or when there is already a definition in a
282 dynamic object. The new symbol is described by NAME, SYM, PSEC,
283 and PVALUE. We set SYM_HASH to the hash table entry. We set
284 OVERRIDE if the old symbol is overriding a new definition. We set
285 TYPE_CHANGE_OK if it is OK for the type to change. We set
286 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
287 change, we mean that we shouldn't warn if the type or size does
288 change. */
290 static boolean
291 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
292 override, type_change_ok, size_change_ok)
293 bfd *abfd;
294 struct bfd_link_info *info;
295 const char *name;
296 Elf_Internal_Sym *sym;
297 asection **psec;
298 bfd_vma *pvalue;
299 struct elf_link_hash_entry **sym_hash;
300 boolean *override;
301 boolean *type_change_ok;
302 boolean *size_change_ok;
304 asection *sec;
305 struct elf_link_hash_entry *h;
306 int bind;
307 bfd *oldbfd;
308 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
310 *override = false;
312 sec = *psec;
313 bind = ELF_ST_BIND (sym->st_info);
315 if (! bfd_is_und_section (sec))
316 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
317 else
318 h = ((struct elf_link_hash_entry *)
319 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
320 if (h == NULL)
321 return false;
322 *sym_hash = h;
324 /* This code is for coping with dynamic objects, and is only useful
325 if we are doing an ELF link. */
326 if (info->hash->creator != abfd->xvec)
327 return true;
329 /* For merging, we only care about real symbols. */
331 while (h->root.type == bfd_link_hash_indirect
332 || h->root.type == bfd_link_hash_warning)
333 h = (struct elf_link_hash_entry *) h->root.u.i.link;
335 /* If we just created the symbol, mark it as being an ELF symbol.
336 Other than that, there is nothing to do--there is no merge issue
337 with a newly defined symbol--so we just return. */
339 if (h->root.type == bfd_link_hash_new)
341 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
342 return true;
345 /* OLDBFD is a BFD associated with the existing symbol. */
347 switch (h->root.type)
349 default:
350 oldbfd = NULL;
351 break;
353 case bfd_link_hash_undefined:
354 case bfd_link_hash_undefweak:
355 oldbfd = h->root.u.undef.abfd;
356 break;
358 case bfd_link_hash_defined:
359 case bfd_link_hash_defweak:
360 oldbfd = h->root.u.def.section->owner;
361 break;
363 case bfd_link_hash_common:
364 oldbfd = h->root.u.c.p->section->owner;
365 break;
368 /* In cases involving weak versioned symbols, we may wind up trying
369 to merge a symbol with itself. Catch that here, to avoid the
370 confusion that results if we try to override a symbol with
371 itself. The additional tests catch cases like
372 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
373 dynamic object, which we do want to handle here. */
374 if (abfd == oldbfd
375 && ((abfd->flags & DYNAMIC) == 0
376 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
377 return true;
379 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
380 respectively, is from a dynamic object. */
382 if ((abfd->flags & DYNAMIC) != 0)
383 newdyn = true;
384 else
385 newdyn = false;
387 if (oldbfd != NULL)
388 olddyn = (oldbfd->flags & DYNAMIC) != 0;
389 else
391 asection *hsec;
393 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
394 indices used by MIPS ELF. */
395 switch (h->root.type)
397 default:
398 hsec = NULL;
399 break;
401 case bfd_link_hash_defined:
402 case bfd_link_hash_defweak:
403 hsec = h->root.u.def.section;
404 break;
406 case bfd_link_hash_common:
407 hsec = h->root.u.c.p->section;
408 break;
411 if (hsec == NULL)
412 olddyn = false;
413 else
414 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
417 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
418 respectively, appear to be a definition rather than reference. */
420 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
421 newdef = false;
422 else
423 newdef = true;
425 if (h->root.type == bfd_link_hash_undefined
426 || h->root.type == bfd_link_hash_undefweak
427 || h->root.type == bfd_link_hash_common)
428 olddef = false;
429 else
430 olddef = true;
432 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
433 symbol, respectively, appears to be a common symbol in a dynamic
434 object. If a symbol appears in an uninitialized section, and is
435 not weak, and is not a function, then it may be a common symbol
436 which was resolved when the dynamic object was created. We want
437 to treat such symbols specially, because they raise special
438 considerations when setting the symbol size: if the symbol
439 appears as a common symbol in a regular object, and the size in
440 the regular object is larger, we must make sure that we use the
441 larger size. This problematic case can always be avoided in C,
442 but it must be handled correctly when using Fortran shared
443 libraries.
445 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
446 likewise for OLDDYNCOMMON and OLDDEF.
448 Note that this test is just a heuristic, and that it is quite
449 possible to have an uninitialized symbol in a shared object which
450 is really a definition, rather than a common symbol. This could
451 lead to some minor confusion when the symbol really is a common
452 symbol in some regular object. However, I think it will be
453 harmless. */
455 if (newdyn
456 && newdef
457 && (sec->flags & SEC_ALLOC) != 0
458 && (sec->flags & SEC_LOAD) == 0
459 && sym->st_size > 0
460 && bind != STB_WEAK
461 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
462 newdyncommon = true;
463 else
464 newdyncommon = false;
466 if (olddyn
467 && olddef
468 && h->root.type == bfd_link_hash_defined
469 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
470 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
471 && (h->root.u.def.section->flags & SEC_LOAD) == 0
472 && h->size > 0
473 && h->type != STT_FUNC)
474 olddyncommon = true;
475 else
476 olddyncommon = false;
478 /* It's OK to change the type if either the existing symbol or the
479 new symbol is weak. */
481 if (h->root.type == bfd_link_hash_defweak
482 || h->root.type == bfd_link_hash_undefweak
483 || bind == STB_WEAK)
484 *type_change_ok = true;
486 /* It's OK to change the size if either the existing symbol or the
487 new symbol is weak, or if the old symbol is undefined. */
489 if (*type_change_ok
490 || h->root.type == bfd_link_hash_undefined)
491 *size_change_ok = true;
493 /* If both the old and the new symbols look like common symbols in a
494 dynamic object, set the size of the symbol to the larger of the
495 two. */
497 if (olddyncommon
498 && newdyncommon
499 && sym->st_size != h->size)
501 /* Since we think we have two common symbols, issue a multiple
502 common warning if desired. Note that we only warn if the
503 size is different. If the size is the same, we simply let
504 the old symbol override the new one as normally happens with
505 symbols defined in dynamic objects. */
507 if (! ((*info->callbacks->multiple_common)
508 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
509 h->size, abfd, bfd_link_hash_common, sym->st_size)))
510 return false;
512 if (sym->st_size > h->size)
513 h->size = sym->st_size;
515 *size_change_ok = true;
518 /* If we are looking at a dynamic object, and we have found a
519 definition, we need to see if the symbol was already defined by
520 some other object. If so, we want to use the existing
521 definition, and we do not want to report a multiple symbol
522 definition error; we do this by clobbering *PSEC to be
523 bfd_und_section_ptr.
525 We treat a common symbol as a definition if the symbol in the
526 shared library is a function, since common symbols always
527 represent variables; this can cause confusion in principle, but
528 any such confusion would seem to indicate an erroneous program or
529 shared library. We also permit a common symbol in a regular
530 object to override a weak symbol in a shared object.
532 We prefer a non-weak definition in a shared library to a weak
533 definition in the executable. */
535 if (newdyn
536 && newdef
537 && (olddef
538 || (h->root.type == bfd_link_hash_common
539 && (bind == STB_WEAK
540 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
541 && (h->root.type != bfd_link_hash_defweak
542 || bind == STB_WEAK))
544 *override = true;
545 newdef = false;
546 newdyncommon = false;
548 *psec = sec = bfd_und_section_ptr;
549 *size_change_ok = true;
551 /* If we get here when the old symbol is a common symbol, then
552 we are explicitly letting it override a weak symbol or
553 function in a dynamic object, and we don't want to warn about
554 a type change. If the old symbol is a defined symbol, a type
555 change warning may still be appropriate. */
557 if (h->root.type == bfd_link_hash_common)
558 *type_change_ok = true;
561 /* Handle the special case of an old common symbol merging with a
562 new symbol which looks like a common symbol in a shared object.
563 We change *PSEC and *PVALUE to make the new symbol look like a
564 common symbol, and let _bfd_generic_link_add_one_symbol will do
565 the right thing. */
567 if (newdyncommon
568 && h->root.type == bfd_link_hash_common)
570 *override = true;
571 newdef = false;
572 newdyncommon = false;
573 *pvalue = sym->st_size;
574 *psec = sec = bfd_com_section_ptr;
575 *size_change_ok = true;
578 /* If the old symbol is from a dynamic object, and the new symbol is
579 a definition which is not from a dynamic object, then the new
580 symbol overrides the old symbol. Symbols from regular files
581 always take precedence over symbols from dynamic objects, even if
582 they are defined after the dynamic object in the link.
584 As above, we again permit a common symbol in a regular object to
585 override a definition in a shared object if the shared object
586 symbol is a function or is weak.
588 As above, we permit a non-weak definition in a shared object to
589 override a weak definition in a regular object. */
591 if (! newdyn
592 && (newdef
593 || (bfd_is_com_section (sec)
594 && (h->root.type == bfd_link_hash_defweak
595 || h->type == STT_FUNC)))
596 && olddyn
597 && olddef
598 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
599 && (bind != STB_WEAK
600 || h->root.type == bfd_link_hash_defweak))
602 /* Change the hash table entry to undefined, and let
603 _bfd_generic_link_add_one_symbol do the right thing with the
604 new definition. */
606 h->root.type = bfd_link_hash_undefined;
607 h->root.u.undef.abfd = h->root.u.def.section->owner;
608 *size_change_ok = true;
610 olddef = false;
611 olddyncommon = false;
613 /* We again permit a type change when a common symbol may be
614 overriding a function. */
616 if (bfd_is_com_section (sec))
617 *type_change_ok = true;
619 /* This union may have been set to be non-NULL when this symbol
620 was seen in a dynamic object. We must force the union to be
621 NULL, so that it is correct for a regular symbol. */
623 h->verinfo.vertree = NULL;
625 /* In this special case, if H is the target of an indirection,
626 we want the caller to frob with H rather than with the
627 indirect symbol. That will permit the caller to redefine the
628 target of the indirection, rather than the indirect symbol
629 itself. FIXME: This will break the -y option if we store a
630 symbol with a different name. */
631 *sym_hash = h;
634 /* Handle the special case of a new common symbol merging with an
635 old symbol that looks like it might be a common symbol defined in
636 a shared object. Note that we have already handled the case in
637 which a new common symbol should simply override the definition
638 in the shared library. */
640 if (! newdyn
641 && bfd_is_com_section (sec)
642 && olddyncommon)
644 /* It would be best if we could set the hash table entry to a
645 common symbol, but we don't know what to use for the section
646 or the alignment. */
647 if (! ((*info->callbacks->multiple_common)
648 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
649 h->size, abfd, bfd_link_hash_common, sym->st_size)))
650 return false;
652 /* If the predumed common symbol in the dynamic object is
653 larger, pretend that the new symbol has its size. */
655 if (h->size > *pvalue)
656 *pvalue = h->size;
658 /* FIXME: We no longer know the alignment required by the symbol
659 in the dynamic object, so we just wind up using the one from
660 the regular object. */
662 olddef = false;
663 olddyncommon = false;
665 h->root.type = bfd_link_hash_undefined;
666 h->root.u.undef.abfd = h->root.u.def.section->owner;
668 *size_change_ok = true;
669 *type_change_ok = true;
671 h->verinfo.vertree = NULL;
674 /* Handle the special case of a weak definition in a regular object
675 followed by a non-weak definition in a shared object. In this
676 case, we prefer the definition in the shared object. */
677 if (olddef
678 && h->root.type == bfd_link_hash_defweak
679 && newdef
680 && newdyn
681 && bind != STB_WEAK)
683 /* To make this work we have to frob the flags so that the rest
684 of the code does not think we are using the regular
685 definition. */
686 h->elf_link_hash_flags &= ~ ELF_LINK_HASH_DEF_REGULAR;
687 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
689 /* If H is the target of an indirection, we want the caller to
690 use H rather than the indirect symbol. Otherwise if we are
691 defining a new indirect symbol we will wind up attaching it
692 to the entry we are overriding. */
693 *sym_hash = h;
696 /* Handle the special case of a non-weak definition in a shared
697 object followed by a weak definition in a regular object. In
698 this case we prefer to definition in the shared object. To make
699 this work we have to tell the caller to not treat the new symbol
700 as a definition. */
701 if (olddef
702 && olddyn
703 && h->root.type != bfd_link_hash_defweak
704 && newdef
705 && ! newdyn
706 && bind == STB_WEAK)
707 *override = true;
709 return true;
712 /* Add symbols from an ELF object file to the linker hash table. */
714 static boolean
715 elf_link_add_object_symbols (abfd, info)
716 bfd *abfd;
717 struct bfd_link_info *info;
719 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
720 const Elf_Internal_Sym *,
721 const char **, flagword *,
722 asection **, bfd_vma *));
723 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
724 asection *, const Elf_Internal_Rela *));
725 boolean collect;
726 Elf_Internal_Shdr *hdr;
727 size_t symcount;
728 size_t extsymcount;
729 size_t extsymoff;
730 Elf_External_Sym *buf = NULL;
731 struct elf_link_hash_entry **sym_hash;
732 boolean dynamic;
733 bfd_byte *dynver = NULL;
734 Elf_External_Versym *extversym = NULL;
735 Elf_External_Versym *ever;
736 Elf_External_Dyn *dynbuf = NULL;
737 struct elf_link_hash_entry *weaks;
738 Elf_External_Sym *esym;
739 Elf_External_Sym *esymend;
741 add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook;
742 collect = get_elf_backend_data (abfd)->collect;
744 if ((abfd->flags & DYNAMIC) == 0)
745 dynamic = false;
746 else
748 dynamic = true;
750 /* You can't use -r against a dynamic object. Also, there's no
751 hope of using a dynamic object which does not exactly match
752 the format of the output file. */
753 if (info->relocateable || info->hash->creator != abfd->xvec)
755 bfd_set_error (bfd_error_invalid_operation);
756 goto error_return;
760 /* As a GNU extension, any input sections which are named
761 .gnu.warning.SYMBOL are treated as warning symbols for the given
762 symbol. This differs from .gnu.warning sections, which generate
763 warnings when they are included in an output file. */
764 if (! info->shared)
766 asection *s;
768 for (s = abfd->sections; s != NULL; s = s->next)
770 const char *name;
772 name = bfd_get_section_name (abfd, s);
773 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
775 char *msg;
776 bfd_size_type sz;
778 name += sizeof ".gnu.warning." - 1;
780 /* If this is a shared object, then look up the symbol
781 in the hash table. If it is there, and it is already
782 been defined, then we will not be using the entry
783 from this shared object, so we don't need to warn.
784 FIXME: If we see the definition in a regular object
785 later on, we will warn, but we shouldn't. The only
786 fix is to keep track of what warnings we are supposed
787 to emit, and then handle them all at the end of the
788 link. */
789 if (dynamic && abfd->xvec == info->hash->creator)
791 struct elf_link_hash_entry *h;
793 h = elf_link_hash_lookup (elf_hash_table (info), name,
794 false, false, true);
796 /* FIXME: What about bfd_link_hash_common? */
797 if (h != NULL
798 && (h->root.type == bfd_link_hash_defined
799 || h->root.type == bfd_link_hash_defweak))
801 /* We don't want to issue this warning. Clobber
802 the section size so that the warning does not
803 get copied into the output file. */
804 s->_raw_size = 0;
805 continue;
809 sz = bfd_section_size (abfd, s);
810 msg = (char *) bfd_alloc (abfd, sz + 1);
811 if (msg == NULL)
812 goto error_return;
814 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
815 goto error_return;
817 msg[sz] = '\0';
819 if (! (_bfd_generic_link_add_one_symbol
820 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
821 false, collect, (struct bfd_link_hash_entry **) NULL)))
822 goto error_return;
824 if (! info->relocateable)
826 /* Clobber the section size so that the warning does
827 not get copied into the output file. */
828 s->_raw_size = 0;
834 /* If this is a dynamic object, we always link against the .dynsym
835 symbol table, not the .symtab symbol table. The dynamic linker
836 will only see the .dynsym symbol table, so there is no reason to
837 look at .symtab for a dynamic object. */
839 if (! dynamic || elf_dynsymtab (abfd) == 0)
840 hdr = &elf_tdata (abfd)->symtab_hdr;
841 else
842 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
844 if (dynamic)
846 /* Read in any version definitions. */
848 if (! _bfd_elf_slurp_version_tables (abfd))
849 goto error_return;
851 /* Read in the symbol versions, but don't bother to convert them
852 to internal format. */
853 if (elf_dynversym (abfd) != 0)
855 Elf_Internal_Shdr *versymhdr;
857 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
858 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
859 if (extversym == NULL)
860 goto error_return;
861 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
862 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
863 != versymhdr->sh_size))
864 goto error_return;
868 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
870 /* The sh_info field of the symtab header tells us where the
871 external symbols start. We don't care about the local symbols at
872 this point. */
873 if (elf_bad_symtab (abfd))
875 extsymcount = symcount;
876 extsymoff = 0;
878 else
880 extsymcount = symcount - hdr->sh_info;
881 extsymoff = hdr->sh_info;
884 buf = ((Elf_External_Sym *)
885 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
886 if (buf == NULL && extsymcount != 0)
887 goto error_return;
889 /* We store a pointer to the hash table entry for each external
890 symbol. */
891 sym_hash = ((struct elf_link_hash_entry **)
892 bfd_alloc (abfd,
893 extsymcount * sizeof (struct elf_link_hash_entry *)));
894 if (sym_hash == NULL)
895 goto error_return;
896 elf_sym_hashes (abfd) = sym_hash;
898 if (! dynamic)
900 /* If we are creating a shared library, create all the dynamic
901 sections immediately. We need to attach them to something,
902 so we attach them to this BFD, provided it is the right
903 format. FIXME: If there are no input BFD's of the same
904 format as the output, we can't make a shared library. */
905 if (info->shared
906 && ! elf_hash_table (info)->dynamic_sections_created
907 && abfd->xvec == info->hash->creator)
909 if (! elf_link_create_dynamic_sections (abfd, info))
910 goto error_return;
913 else
915 asection *s;
916 boolean add_needed;
917 const char *name;
918 bfd_size_type oldsize;
919 bfd_size_type strindex;
921 /* Find the name to use in a DT_NEEDED entry that refers to this
922 object. If the object has a DT_SONAME entry, we use it.
923 Otherwise, if the generic linker stuck something in
924 elf_dt_name, we use that. Otherwise, we just use the file
925 name. If the generic linker put a null string into
926 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
927 there is a DT_SONAME entry. */
928 add_needed = true;
929 name = bfd_get_filename (abfd);
930 if (elf_dt_name (abfd) != NULL)
932 name = elf_dt_name (abfd);
933 if (*name == '\0')
934 add_needed = false;
936 s = bfd_get_section_by_name (abfd, ".dynamic");
937 if (s != NULL)
939 Elf_External_Dyn *extdyn;
940 Elf_External_Dyn *extdynend;
941 int elfsec;
942 unsigned long link;
944 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
945 if (dynbuf == NULL)
946 goto error_return;
948 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
949 (file_ptr) 0, s->_raw_size))
950 goto error_return;
952 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
953 if (elfsec == -1)
954 goto error_return;
955 link = elf_elfsections (abfd)[elfsec]->sh_link;
958 /* The shared libraries distributed with hpux11 have a bogus
959 sh_link field for the ".dynamic" section. This code detects
960 when LINK refers to a section that is not a string table and
961 tries to find the string table for the ".dynsym" section
962 instead. */
963 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
964 if (hdr->sh_type != SHT_STRTAB)
966 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
967 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
968 if (elfsec == -1)
969 goto error_return;
970 link = elf_elfsections (abfd)[elfsec]->sh_link;
974 extdyn = dynbuf;
975 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
976 for (; extdyn < extdynend; extdyn++)
978 Elf_Internal_Dyn dyn;
980 elf_swap_dyn_in (abfd, extdyn, &dyn);
981 if (dyn.d_tag == DT_SONAME)
983 name = bfd_elf_string_from_elf_section (abfd, link,
984 dyn.d_un.d_val);
985 if (name == NULL)
986 goto error_return;
988 if (dyn.d_tag == DT_NEEDED)
990 struct bfd_link_needed_list *n, **pn;
991 char *fnm, *anm;
993 n = ((struct bfd_link_needed_list *)
994 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
995 fnm = bfd_elf_string_from_elf_section (abfd, link,
996 dyn.d_un.d_val);
997 if (n == NULL || fnm == NULL)
998 goto error_return;
999 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1000 if (anm == NULL)
1001 goto error_return;
1002 strcpy (anm, fnm);
1003 n->name = anm;
1004 n->by = abfd;
1005 n->next = NULL;
1006 for (pn = &elf_hash_table (info)->needed;
1007 *pn != NULL;
1008 pn = &(*pn)->next)
1010 *pn = n;
1014 free (dynbuf);
1015 dynbuf = NULL;
1018 /* We do not want to include any of the sections in a dynamic
1019 object in the output file. We hack by simply clobbering the
1020 list of sections in the BFD. This could be handled more
1021 cleanly by, say, a new section flag; the existing
1022 SEC_NEVER_LOAD flag is not the one we want, because that one
1023 still implies that the section takes up space in the output
1024 file. */
1025 abfd->sections = NULL;
1026 abfd->section_count = 0;
1028 /* If this is the first dynamic object found in the link, create
1029 the special sections required for dynamic linking. */
1030 if (! elf_hash_table (info)->dynamic_sections_created)
1032 if (! elf_link_create_dynamic_sections (abfd, info))
1033 goto error_return;
1036 if (add_needed)
1038 /* Add a DT_NEEDED entry for this dynamic object. */
1039 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1040 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1041 true, false);
1042 if (strindex == (bfd_size_type) -1)
1043 goto error_return;
1045 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1047 asection *sdyn;
1048 Elf_External_Dyn *dyncon, *dynconend;
1050 /* The hash table size did not change, which means that
1051 the dynamic object name was already entered. If we
1052 have already included this dynamic object in the
1053 link, just ignore it. There is no reason to include
1054 a particular dynamic object more than once. */
1055 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1056 ".dynamic");
1057 BFD_ASSERT (sdyn != NULL);
1059 dyncon = (Elf_External_Dyn *) sdyn->contents;
1060 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1061 sdyn->_raw_size);
1062 for (; dyncon < dynconend; dyncon++)
1064 Elf_Internal_Dyn dyn;
1066 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1067 &dyn);
1068 if (dyn.d_tag == DT_NEEDED
1069 && dyn.d_un.d_val == strindex)
1071 if (buf != NULL)
1072 free (buf);
1073 if (extversym != NULL)
1074 free (extversym);
1075 return true;
1080 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1081 goto error_return;
1084 /* Save the SONAME, if there is one, because sometimes the
1085 linker emulation code will need to know it. */
1086 if (*name == '\0')
1087 name = bfd_get_filename (abfd);
1088 elf_dt_name (abfd) = name;
1091 if (bfd_seek (abfd,
1092 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1093 SEEK_SET) != 0
1094 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1095 != extsymcount * sizeof (Elf_External_Sym)))
1096 goto error_return;
1098 weaks = NULL;
1100 ever = extversym != NULL ? extversym + extsymoff : NULL;
1101 esymend = buf + extsymcount;
1102 for (esym = buf;
1103 esym < esymend;
1104 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1106 Elf_Internal_Sym sym;
1107 int bind;
1108 bfd_vma value;
1109 asection *sec;
1110 flagword flags;
1111 const char *name;
1112 struct elf_link_hash_entry *h;
1113 boolean definition;
1114 boolean size_change_ok, type_change_ok;
1115 boolean new_weakdef;
1116 unsigned int old_alignment;
1118 elf_swap_symbol_in (abfd, esym, &sym);
1120 flags = BSF_NO_FLAGS;
1121 sec = NULL;
1122 value = sym.st_value;
1123 *sym_hash = NULL;
1125 bind = ELF_ST_BIND (sym.st_info);
1126 if (bind == STB_LOCAL)
1128 /* This should be impossible, since ELF requires that all
1129 global symbols follow all local symbols, and that sh_info
1130 point to the first global symbol. Unfortunatealy, Irix 5
1131 screws this up. */
1132 continue;
1134 else if (bind == STB_GLOBAL)
1136 if (sym.st_shndx != SHN_UNDEF
1137 && sym.st_shndx != SHN_COMMON)
1138 flags = BSF_GLOBAL;
1139 else
1140 flags = 0;
1142 else if (bind == STB_WEAK)
1143 flags = BSF_WEAK;
1144 else
1146 /* Leave it up to the processor backend. */
1149 if (sym.st_shndx == SHN_UNDEF)
1150 sec = bfd_und_section_ptr;
1151 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1153 sec = section_from_elf_index (abfd, sym.st_shndx);
1154 if (sec == NULL)
1155 sec = bfd_abs_section_ptr;
1156 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1157 value -= sec->vma;
1159 else if (sym.st_shndx == SHN_ABS)
1160 sec = bfd_abs_section_ptr;
1161 else if (sym.st_shndx == SHN_COMMON)
1163 sec = bfd_com_section_ptr;
1164 /* What ELF calls the size we call the value. What ELF
1165 calls the value we call the alignment. */
1166 value = sym.st_size;
1168 else
1170 /* Leave it up to the processor backend. */
1173 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1174 if (name == (const char *) NULL)
1175 goto error_return;
1177 if (add_symbol_hook)
1179 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1180 &value))
1181 goto error_return;
1183 /* The hook function sets the name to NULL if this symbol
1184 should be skipped for some reason. */
1185 if (name == (const char *) NULL)
1186 continue;
1189 /* Sanity check that all possibilities were handled. */
1190 if (sec == (asection *) NULL)
1192 bfd_set_error (bfd_error_bad_value);
1193 goto error_return;
1196 if (bfd_is_und_section (sec)
1197 || bfd_is_com_section (sec))
1198 definition = false;
1199 else
1200 definition = true;
1202 size_change_ok = false;
1203 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1204 old_alignment = 0;
1205 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1207 Elf_Internal_Versym iver;
1208 unsigned int vernum = 0;
1209 boolean override;
1211 if (ever != NULL)
1213 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1214 vernum = iver.vs_vers & VERSYM_VERSION;
1216 /* If this is a hidden symbol, or if it is not version
1217 1, we append the version name to the symbol name.
1218 However, we do not modify a non-hidden absolute
1219 symbol, because it might be the version symbol
1220 itself. FIXME: What if it isn't? */
1221 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1222 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1224 const char *verstr;
1225 int namelen, newlen;
1226 char *newname, *p;
1228 if (sym.st_shndx != SHN_UNDEF)
1230 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1232 (*_bfd_error_handler)
1233 (_("%s: %s: invalid version %u (max %d)"),
1234 bfd_get_filename (abfd), name, vernum,
1235 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1236 bfd_set_error (bfd_error_bad_value);
1237 goto error_return;
1239 else if (vernum > 1)
1240 verstr =
1241 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1242 else
1243 verstr = "";
1245 else
1247 /* We cannot simply test for the number of
1248 entries in the VERNEED section since the
1249 numbers for the needed versions do not start
1250 at 0. */
1251 Elf_Internal_Verneed *t;
1253 verstr = NULL;
1254 for (t = elf_tdata (abfd)->verref;
1255 t != NULL;
1256 t = t->vn_nextref)
1258 Elf_Internal_Vernaux *a;
1260 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1262 if (a->vna_other == vernum)
1264 verstr = a->vna_nodename;
1265 break;
1268 if (a != NULL)
1269 break;
1271 if (verstr == NULL)
1273 (*_bfd_error_handler)
1274 (_("%s: %s: invalid needed version %d"),
1275 bfd_get_filename (abfd), name, vernum);
1276 bfd_set_error (bfd_error_bad_value);
1277 goto error_return;
1281 namelen = strlen (name);
1282 newlen = namelen + strlen (verstr) + 2;
1283 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1284 ++newlen;
1286 newname = (char *) bfd_alloc (abfd, newlen);
1287 if (newname == NULL)
1288 goto error_return;
1289 strcpy (newname, name);
1290 p = newname + namelen;
1291 *p++ = ELF_VER_CHR;
1292 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1293 *p++ = ELF_VER_CHR;
1294 strcpy (p, verstr);
1296 name = newname;
1300 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1301 sym_hash, &override, &type_change_ok,
1302 &size_change_ok))
1303 goto error_return;
1305 if (override)
1306 definition = false;
1308 h = *sym_hash;
1309 while (h->root.type == bfd_link_hash_indirect
1310 || h->root.type == bfd_link_hash_warning)
1311 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1313 /* Remember the old alignment if this is a common symbol, so
1314 that we don't reduce the alignment later on. We can't
1315 check later, because _bfd_generic_link_add_one_symbol
1316 will set a default for the alignment which we want to
1317 override. */
1318 if (h->root.type == bfd_link_hash_common)
1319 old_alignment = h->root.u.c.p->alignment_power;
1321 if (elf_tdata (abfd)->verdef != NULL
1322 && ! override
1323 && vernum > 1
1324 && definition)
1325 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1328 if (! (_bfd_generic_link_add_one_symbol
1329 (info, abfd, name, flags, sec, value, (const char *) NULL,
1330 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1331 goto error_return;
1333 h = *sym_hash;
1334 while (h->root.type == bfd_link_hash_indirect
1335 || h->root.type == bfd_link_hash_warning)
1336 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1337 *sym_hash = h;
1339 new_weakdef = false;
1340 if (dynamic
1341 && definition
1342 && (flags & BSF_WEAK) != 0
1343 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1344 && info->hash->creator->flavour == bfd_target_elf_flavour
1345 && h->weakdef == NULL)
1347 /* Keep a list of all weak defined non function symbols from
1348 a dynamic object, using the weakdef field. Later in this
1349 function we will set the weakdef field to the correct
1350 value. We only put non-function symbols from dynamic
1351 objects on this list, because that happens to be the only
1352 time we need to know the normal symbol corresponding to a
1353 weak symbol, and the information is time consuming to
1354 figure out. If the weakdef field is not already NULL,
1355 then this symbol was already defined by some previous
1356 dynamic object, and we will be using that previous
1357 definition anyhow. */
1359 h->weakdef = weaks;
1360 weaks = h;
1361 new_weakdef = true;
1364 /* Set the alignment of a common symbol. */
1365 if (sym.st_shndx == SHN_COMMON
1366 && h->root.type == bfd_link_hash_common)
1368 unsigned int align;
1370 align = bfd_log2 (sym.st_value);
1371 if (align > old_alignment)
1372 h->root.u.c.p->alignment_power = align;
1375 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1377 int old_flags;
1378 boolean dynsym;
1379 int new_flag;
1381 /* Remember the symbol size and type. */
1382 if (sym.st_size != 0
1383 && (definition || h->size == 0))
1385 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1386 (*_bfd_error_handler)
1387 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1388 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1389 bfd_get_filename (abfd));
1391 h->size = sym.st_size;
1394 /* If this is a common symbol, then we always want H->SIZE
1395 to be the size of the common symbol. The code just above
1396 won't fix the size if a common symbol becomes larger. We
1397 don't warn about a size change here, because that is
1398 covered by --warn-common. */
1399 if (h->root.type == bfd_link_hash_common)
1400 h->size = h->root.u.c.size;
1402 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1403 && (definition || h->type == STT_NOTYPE))
1405 if (h->type != STT_NOTYPE
1406 && h->type != ELF_ST_TYPE (sym.st_info)
1407 && ! type_change_ok)
1408 (*_bfd_error_handler)
1409 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1410 name, h->type, ELF_ST_TYPE (sym.st_info),
1411 bfd_get_filename (abfd));
1413 h->type = ELF_ST_TYPE (sym.st_info);
1416 if (sym.st_other != 0
1417 && (definition || h->other == 0))
1418 h->other = sym.st_other;
1420 /* Set a flag in the hash table entry indicating the type of
1421 reference or definition we just found. Keep a count of
1422 the number of dynamic symbols we find. A dynamic symbol
1423 is one which is referenced or defined by both a regular
1424 object and a shared object. */
1425 old_flags = h->elf_link_hash_flags;
1426 dynsym = false;
1427 if (! dynamic)
1429 if (! definition)
1431 new_flag = ELF_LINK_HASH_REF_REGULAR;
1432 if (bind != STB_WEAK)
1433 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1435 else
1436 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1437 if (info->shared
1438 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1439 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1440 dynsym = true;
1442 else
1444 if (! definition)
1445 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1446 else
1447 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1448 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1449 | ELF_LINK_HASH_REF_REGULAR)) != 0
1450 || (h->weakdef != NULL
1451 && ! new_weakdef
1452 && h->weakdef->dynindx != -1))
1453 dynsym = true;
1456 h->elf_link_hash_flags |= new_flag;
1458 /* If this symbol has a version, and it is the default
1459 version, we create an indirect symbol from the default
1460 name to the fully decorated name. This will cause
1461 external references which do not specify a version to be
1462 bound to this version of the symbol. */
1463 if (definition)
1465 char *p;
1467 p = strchr (name, ELF_VER_CHR);
1468 if (p != NULL && p[1] == ELF_VER_CHR)
1470 char *shortname;
1471 struct elf_link_hash_entry *hi;
1472 boolean override;
1474 shortname = bfd_hash_allocate (&info->hash->table,
1475 p - name + 1);
1476 if (shortname == NULL)
1477 goto error_return;
1478 strncpy (shortname, name, p - name);
1479 shortname[p - name] = '\0';
1481 /* We are going to create a new symbol. Merge it
1482 with any existing symbol with this name. For the
1483 purposes of the merge, act as though we were
1484 defining the symbol we just defined, although we
1485 actually going to define an indirect symbol. */
1486 type_change_ok = false;
1487 size_change_ok = false;
1488 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1489 &value, &hi, &override,
1490 &type_change_ok, &size_change_ok))
1491 goto error_return;
1493 if (! override)
1495 if (! (_bfd_generic_link_add_one_symbol
1496 (info, abfd, shortname, BSF_INDIRECT,
1497 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1498 collect, (struct bfd_link_hash_entry **) &hi)))
1499 goto error_return;
1501 else
1503 /* In this case the symbol named SHORTNAME is
1504 overriding the indirect symbol we want to
1505 add. We were planning on making SHORTNAME an
1506 indirect symbol referring to NAME. SHORTNAME
1507 is the name without a version. NAME is the
1508 fully versioned name, and it is the default
1509 version.
1511 Overriding means that we already saw a
1512 definition for the symbol SHORTNAME in a
1513 regular object, and it is overriding the
1514 symbol defined in the dynamic object.
1516 When this happens, we actually want to change
1517 NAME, the symbol we just added, to refer to
1518 SHORTNAME. This will cause references to
1519 NAME in the shared object to become
1520 references to SHORTNAME in the regular
1521 object. This is what we expect when we
1522 override a function in a shared object: that
1523 the references in the shared object will be
1524 mapped to the definition in the regular
1525 object. */
1527 while (hi->root.type == bfd_link_hash_indirect
1528 || hi->root.type == bfd_link_hash_warning)
1529 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1531 h->root.type = bfd_link_hash_indirect;
1532 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1533 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1535 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1536 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1537 if (hi->elf_link_hash_flags
1538 & (ELF_LINK_HASH_REF_REGULAR
1539 | ELF_LINK_HASH_DEF_REGULAR))
1541 if (! _bfd_elf_link_record_dynamic_symbol (info,
1542 hi))
1543 goto error_return;
1547 /* Now set HI to H, so that the following code
1548 will set the other fields correctly. */
1549 hi = h;
1552 /* If there is a duplicate definition somewhere,
1553 then HI may not point to an indirect symbol. We
1554 will have reported an error to the user in that
1555 case. */
1557 if (hi->root.type == bfd_link_hash_indirect)
1559 struct elf_link_hash_entry *ht;
1561 /* If the symbol became indirect, then we assume
1562 that we have not seen a definition before. */
1563 BFD_ASSERT ((hi->elf_link_hash_flags
1564 & (ELF_LINK_HASH_DEF_DYNAMIC
1565 | ELF_LINK_HASH_DEF_REGULAR))
1566 == 0);
1568 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1570 /* Copy down any references that we may have
1571 already seen to the symbol which just became
1572 indirect. */
1573 ht->elf_link_hash_flags |=
1574 (hi->elf_link_hash_flags
1575 & (ELF_LINK_HASH_REF_DYNAMIC
1576 | ELF_LINK_HASH_REF_REGULAR
1577 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
1578 | ELF_LINK_NON_GOT_REF));
1580 /* Copy over the global and procedure linkage table
1581 offset entries. These may have been already set
1582 up by a check_relocs routine. */
1583 if (ht->got.offset == (bfd_vma) -1)
1585 ht->got.offset = hi->got.offset;
1586 hi->got.offset = (bfd_vma) -1;
1588 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1590 if (ht->plt.offset == (bfd_vma) -1)
1592 ht->plt.offset = hi->plt.offset;
1593 hi->plt.offset = (bfd_vma) -1;
1595 BFD_ASSERT (hi->plt.offset == (bfd_vma) -1);
1597 if (ht->dynindx == -1)
1599 ht->dynindx = hi->dynindx;
1600 ht->dynstr_index = hi->dynstr_index;
1601 hi->dynindx = -1;
1602 hi->dynstr_index = 0;
1604 BFD_ASSERT (hi->dynindx == -1);
1606 /* FIXME: There may be other information to copy
1607 over for particular targets. */
1609 /* See if the new flags lead us to realize that
1610 the symbol must be dynamic. */
1611 if (! dynsym)
1613 if (! dynamic)
1615 if (info->shared
1616 || ((hi->elf_link_hash_flags
1617 & ELF_LINK_HASH_REF_DYNAMIC)
1618 != 0))
1619 dynsym = true;
1621 else
1623 if ((hi->elf_link_hash_flags
1624 & ELF_LINK_HASH_REF_REGULAR) != 0)
1625 dynsym = true;
1630 /* We also need to define an indirection from the
1631 nondefault version of the symbol. */
1633 shortname = bfd_hash_allocate (&info->hash->table,
1634 strlen (name));
1635 if (shortname == NULL)
1636 goto error_return;
1637 strncpy (shortname, name, p - name);
1638 strcpy (shortname + (p - name), p + 1);
1640 /* Once again, merge with any existing symbol. */
1641 type_change_ok = false;
1642 size_change_ok = false;
1643 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1644 &value, &hi, &override,
1645 &type_change_ok, &size_change_ok))
1646 goto error_return;
1648 if (override)
1650 /* Here SHORTNAME is a versioned name, so we
1651 don't expect to see the type of override we
1652 do in the case above. */
1653 (*_bfd_error_handler)
1654 (_("%s: warning: unexpected redefinition of `%s'"),
1655 bfd_get_filename (abfd), shortname);
1657 else
1659 if (! (_bfd_generic_link_add_one_symbol
1660 (info, abfd, shortname, BSF_INDIRECT,
1661 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1662 collect, (struct bfd_link_hash_entry **) &hi)))
1663 goto error_return;
1665 /* If there is a duplicate definition somewhere,
1666 then HI may not point to an indirect symbol.
1667 We will have reported an error to the user in
1668 that case. */
1670 if (hi->root.type == bfd_link_hash_indirect)
1672 /* If the symbol became indirect, then we
1673 assume that we have not seen a definition
1674 before. */
1675 BFD_ASSERT ((hi->elf_link_hash_flags
1676 & (ELF_LINK_HASH_DEF_DYNAMIC
1677 | ELF_LINK_HASH_DEF_REGULAR))
1678 == 0);
1680 /* Copy down any references that we may have
1681 already seen to the symbol which just
1682 became indirect. */
1683 h->elf_link_hash_flags |=
1684 (hi->elf_link_hash_flags
1685 & (ELF_LINK_HASH_REF_DYNAMIC
1686 | ELF_LINK_HASH_REF_REGULAR
1687 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
1688 | ELF_LINK_NON_GOT_REF));
1690 /* Copy over the global and procedure linkage
1691 table offset entries. These may have been
1692 already set up by a check_relocs routine. */
1693 if (h->got.offset == (bfd_vma) -1)
1695 h->got.offset = hi->got.offset;
1696 hi->got.offset = (bfd_vma) -1;
1698 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1700 if (h->plt.offset == (bfd_vma) -1)
1702 h->plt.offset = hi->plt.offset;
1703 hi->plt.offset = (bfd_vma) -1;
1705 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1707 if (h->dynindx == -1)
1709 h->dynindx = hi->dynindx;
1710 h->dynstr_index = hi->dynstr_index;
1711 hi->dynindx = -1;
1712 hi->dynstr_index = 0;
1714 BFD_ASSERT (hi->dynindx == -1);
1716 /* FIXME: There may be other information to
1717 copy over for particular targets. */
1719 /* See if the new flags lead us to realize
1720 that the symbol must be dynamic. */
1721 if (! dynsym)
1723 if (! dynamic)
1725 if (info->shared
1726 || ((hi->elf_link_hash_flags
1727 & ELF_LINK_HASH_REF_DYNAMIC)
1728 != 0))
1729 dynsym = true;
1731 else
1733 if ((hi->elf_link_hash_flags
1734 & ELF_LINK_HASH_REF_REGULAR) != 0)
1735 dynsym = true;
1743 if (dynsym && h->dynindx == -1)
1745 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1746 goto error_return;
1747 if (h->weakdef != NULL
1748 && ! new_weakdef
1749 && h->weakdef->dynindx == -1)
1751 if (! _bfd_elf_link_record_dynamic_symbol (info,
1752 h->weakdef))
1753 goto error_return;
1759 /* Now set the weakdefs field correctly for all the weak defined
1760 symbols we found. The only way to do this is to search all the
1761 symbols. Since we only need the information for non functions in
1762 dynamic objects, that's the only time we actually put anything on
1763 the list WEAKS. We need this information so that if a regular
1764 object refers to a symbol defined weakly in a dynamic object, the
1765 real symbol in the dynamic object is also put in the dynamic
1766 symbols; we also must arrange for both symbols to point to the
1767 same memory location. We could handle the general case of symbol
1768 aliasing, but a general symbol alias can only be generated in
1769 assembler code, handling it correctly would be very time
1770 consuming, and other ELF linkers don't handle general aliasing
1771 either. */
1772 while (weaks != NULL)
1774 struct elf_link_hash_entry *hlook;
1775 asection *slook;
1776 bfd_vma vlook;
1777 struct elf_link_hash_entry **hpp;
1778 struct elf_link_hash_entry **hppend;
1780 hlook = weaks;
1781 weaks = hlook->weakdef;
1782 hlook->weakdef = NULL;
1784 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1785 || hlook->root.type == bfd_link_hash_defweak
1786 || hlook->root.type == bfd_link_hash_common
1787 || hlook->root.type == bfd_link_hash_indirect);
1788 slook = hlook->root.u.def.section;
1789 vlook = hlook->root.u.def.value;
1791 hpp = elf_sym_hashes (abfd);
1792 hppend = hpp + extsymcount;
1793 for (; hpp < hppend; hpp++)
1795 struct elf_link_hash_entry *h;
1797 h = *hpp;
1798 if (h != NULL && h != hlook
1799 && h->root.type == bfd_link_hash_defined
1800 && h->root.u.def.section == slook
1801 && h->root.u.def.value == vlook)
1803 hlook->weakdef = h;
1805 /* If the weak definition is in the list of dynamic
1806 symbols, make sure the real definition is put there
1807 as well. */
1808 if (hlook->dynindx != -1
1809 && h->dynindx == -1)
1811 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1812 goto error_return;
1815 /* If the real definition is in the list of dynamic
1816 symbols, make sure the weak definition is put there
1817 as well. If we don't do this, then the dynamic
1818 loader might not merge the entries for the real
1819 definition and the weak definition. */
1820 if (h->dynindx != -1
1821 && hlook->dynindx == -1)
1823 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1824 goto error_return;
1827 break;
1832 if (buf != NULL)
1834 free (buf);
1835 buf = NULL;
1838 if (extversym != NULL)
1840 free (extversym);
1841 extversym = NULL;
1844 /* If this object is the same format as the output object, and it is
1845 not a shared library, then let the backend look through the
1846 relocs.
1848 This is required to build global offset table entries and to
1849 arrange for dynamic relocs. It is not required for the
1850 particular common case of linking non PIC code, even when linking
1851 against shared libraries, but unfortunately there is no way of
1852 knowing whether an object file has been compiled PIC or not.
1853 Looking through the relocs is not particularly time consuming.
1854 The problem is that we must either (1) keep the relocs in memory,
1855 which causes the linker to require additional runtime memory or
1856 (2) read the relocs twice from the input file, which wastes time.
1857 This would be a good case for using mmap.
1859 I have no idea how to handle linking PIC code into a file of a
1860 different format. It probably can't be done. */
1861 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1862 if (! dynamic
1863 && abfd->xvec == info->hash->creator
1864 && check_relocs != NULL)
1866 asection *o;
1868 for (o = abfd->sections; o != NULL; o = o->next)
1870 Elf_Internal_Rela *internal_relocs;
1871 boolean ok;
1873 if ((o->flags & SEC_RELOC) == 0
1874 || o->reloc_count == 0
1875 || ((info->strip == strip_all || info->strip == strip_debugger)
1876 && (o->flags & SEC_DEBUGGING) != 0)
1877 || bfd_is_abs_section (o->output_section))
1878 continue;
1880 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1881 (abfd, o, (PTR) NULL,
1882 (Elf_Internal_Rela *) NULL,
1883 info->keep_memory));
1884 if (internal_relocs == NULL)
1885 goto error_return;
1887 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1889 if (! info->keep_memory)
1890 free (internal_relocs);
1892 if (! ok)
1893 goto error_return;
1897 /* If this is a non-traditional, non-relocateable link, try to
1898 optimize the handling of the .stab/.stabstr sections. */
1899 if (! dynamic
1900 && ! info->relocateable
1901 && ! info->traditional_format
1902 && info->hash->creator->flavour == bfd_target_elf_flavour
1903 && (info->strip != strip_all && info->strip != strip_debugger))
1905 asection *stab, *stabstr;
1907 stab = bfd_get_section_by_name (abfd, ".stab");
1908 if (stab != NULL)
1910 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
1912 if (stabstr != NULL)
1914 struct bfd_elf_section_data *secdata;
1916 secdata = elf_section_data (stab);
1917 if (! _bfd_link_section_stabs (abfd,
1918 &elf_hash_table (info)->stab_info,
1919 stab, stabstr,
1920 &secdata->stab_info))
1921 goto error_return;
1926 return true;
1928 error_return:
1929 if (buf != NULL)
1930 free (buf);
1931 if (dynbuf != NULL)
1932 free (dynbuf);
1933 if (dynver != NULL)
1934 free (dynver);
1935 if (extversym != NULL)
1936 free (extversym);
1937 return false;
1940 /* Create some sections which will be filled in with dynamic linking
1941 information. ABFD is an input file which requires dynamic sections
1942 to be created. The dynamic sections take up virtual memory space
1943 when the final executable is run, so we need to create them before
1944 addresses are assigned to the output sections. We work out the
1945 actual contents and size of these sections later. */
1947 boolean
1948 elf_link_create_dynamic_sections (abfd, info)
1949 bfd *abfd;
1950 struct bfd_link_info *info;
1952 flagword flags;
1953 register asection *s;
1954 struct elf_link_hash_entry *h;
1955 struct elf_backend_data *bed;
1957 if (elf_hash_table (info)->dynamic_sections_created)
1958 return true;
1960 /* Make sure that all dynamic sections use the same input BFD. */
1961 if (elf_hash_table (info)->dynobj == NULL)
1962 elf_hash_table (info)->dynobj = abfd;
1963 else
1964 abfd = elf_hash_table (info)->dynobj;
1966 /* Note that we set the SEC_IN_MEMORY flag for all of these
1967 sections. */
1968 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
1969 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1971 /* A dynamically linked executable has a .interp section, but a
1972 shared library does not. */
1973 if (! info->shared)
1975 s = bfd_make_section (abfd, ".interp");
1976 if (s == NULL
1977 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1978 return false;
1981 /* Create sections to hold version informations. These are removed
1982 if they are not needed. */
1983 s = bfd_make_section (abfd, ".gnu.version_d");
1984 if (s == NULL
1985 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1986 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1987 return false;
1989 s = bfd_make_section (abfd, ".gnu.version");
1990 if (s == NULL
1991 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1992 || ! bfd_set_section_alignment (abfd, s, 1))
1993 return false;
1995 s = bfd_make_section (abfd, ".gnu.version_r");
1996 if (s == NULL
1997 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1998 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1999 return false;
2001 s = bfd_make_section (abfd, ".dynsym");
2002 if (s == NULL
2003 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2004 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2005 return false;
2007 s = bfd_make_section (abfd, ".dynstr");
2008 if (s == NULL
2009 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2010 return false;
2012 /* Create a strtab to hold the dynamic symbol names. */
2013 if (elf_hash_table (info)->dynstr == NULL)
2015 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2016 if (elf_hash_table (info)->dynstr == NULL)
2017 return false;
2020 s = bfd_make_section (abfd, ".dynamic");
2021 if (s == NULL
2022 || ! bfd_set_section_flags (abfd, s, flags)
2023 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2024 return false;
2026 /* The special symbol _DYNAMIC is always set to the start of the
2027 .dynamic section. This call occurs before we have processed the
2028 symbols for any dynamic object, so we don't have to worry about
2029 overriding a dynamic definition. We could set _DYNAMIC in a
2030 linker script, but we only want to define it if we are, in fact,
2031 creating a .dynamic section. We don't want to define it if there
2032 is no .dynamic section, since on some ELF platforms the start up
2033 code examines it to decide how to initialize the process. */
2034 h = NULL;
2035 if (! (_bfd_generic_link_add_one_symbol
2036 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2037 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2038 (struct bfd_link_hash_entry **) &h)))
2039 return false;
2040 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2041 h->type = STT_OBJECT;
2043 if (info->shared
2044 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2045 return false;
2047 bed = get_elf_backend_data (abfd);
2049 s = bfd_make_section (abfd, ".hash");
2050 if (s == NULL
2051 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2052 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2053 return false;
2054 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2056 /* Let the backend create the rest of the sections. This lets the
2057 backend set the right flags. The backend will normally create
2058 the .got and .plt sections. */
2059 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2060 return false;
2062 elf_hash_table (info)->dynamic_sections_created = true;
2064 return true;
2067 /* Add an entry to the .dynamic table. */
2069 boolean
2070 elf_add_dynamic_entry (info, tag, val)
2071 struct bfd_link_info *info;
2072 bfd_vma tag;
2073 bfd_vma val;
2075 Elf_Internal_Dyn dyn;
2076 bfd *dynobj;
2077 asection *s;
2078 size_t newsize;
2079 bfd_byte *newcontents;
2081 dynobj = elf_hash_table (info)->dynobj;
2083 s = bfd_get_section_by_name (dynobj, ".dynamic");
2084 BFD_ASSERT (s != NULL);
2086 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2087 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2088 if (newcontents == NULL)
2089 return false;
2091 dyn.d_tag = tag;
2092 dyn.d_un.d_val = val;
2093 elf_swap_dyn_out (dynobj, &dyn,
2094 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2096 s->_raw_size = newsize;
2097 s->contents = newcontents;
2099 return true;
2102 /* Record a new local dynamic symbol. */
2104 boolean
2105 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2106 struct bfd_link_info *info;
2107 bfd *input_bfd;
2108 long input_indx;
2110 struct elf_link_local_dynamic_entry *entry;
2111 struct elf_link_hash_table *eht;
2112 struct bfd_strtab_hash *dynstr;
2113 Elf_External_Sym esym;
2114 unsigned long dynstr_index;
2115 char *name;
2117 /* See if the entry exists already. */
2118 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2119 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2120 return true;
2122 entry = (struct elf_link_local_dynamic_entry *)
2123 bfd_alloc (input_bfd, sizeof (*entry));
2124 if (entry == NULL)
2125 return false;
2127 /* Go find the symbol, so that we can find it's name. */
2128 if (bfd_seek (input_bfd,
2129 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2130 + input_indx * sizeof (Elf_External_Sym)),
2131 SEEK_SET) != 0
2132 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2133 != sizeof (Elf_External_Sym)))
2134 return false;
2135 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2137 name = (bfd_elf_string_from_elf_section
2138 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2139 entry->isym.st_name));
2141 dynstr = elf_hash_table (info)->dynstr;
2142 if (dynstr == NULL)
2144 /* Create a strtab to hold the dynamic symbol names. */
2145 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2146 if (dynstr == NULL)
2147 return false;
2150 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2151 if (dynstr_index == (unsigned long) -1)
2152 return false;
2153 entry->isym.st_name = dynstr_index;
2155 eht = elf_hash_table (info);
2157 entry->next = eht->dynlocal;
2158 eht->dynlocal = entry;
2159 entry->input_bfd = input_bfd;
2160 entry->input_indx = input_indx;
2161 eht->dynsymcount++;
2163 /* Whatever binding the symbol had before, it's now local. */
2164 entry->isym.st_info
2165 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2167 /* The dynindx will be set at the end of size_dynamic_sections. */
2169 return true;
2173 /* Read and swap the relocs from the section indicated by SHDR. This
2174 may be either a REL or a RELA section. The relocations are
2175 translated into RELA relocations and stored in INTERNAL_RELOCS,
2176 which should have already been allocated to contain enough space.
2177 The EXTERNAL_RELOCS are a buffer where the external form of the
2178 relocations should be stored.
2180 Returns false if something goes wrong. */
2182 static boolean
2183 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2184 internal_relocs)
2185 bfd *abfd;
2186 Elf_Internal_Shdr *shdr;
2187 PTR external_relocs;
2188 Elf_Internal_Rela *internal_relocs;
2190 struct elf_backend_data *bed;
2192 /* If there aren't any relocations, that's OK. */
2193 if (!shdr)
2194 return true;
2196 /* Position ourselves at the start of the section. */
2197 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2198 return false;
2200 /* Read the relocations. */
2201 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2202 != shdr->sh_size)
2203 return false;
2205 bed = get_elf_backend_data (abfd);
2207 /* Convert the external relocations to the internal format. */
2208 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2210 Elf_External_Rel *erel;
2211 Elf_External_Rel *erelend;
2212 Elf_Internal_Rela *irela;
2213 Elf_Internal_Rel *irel;
2215 erel = (Elf_External_Rel *) external_relocs;
2216 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2217 irela = internal_relocs;
2218 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2219 * sizeof (Elf_Internal_Rel)));
2220 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2222 unsigned char i;
2224 if (bed->s->swap_reloc_in)
2225 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2226 else
2227 elf_swap_reloc_in (abfd, erel, irel);
2229 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2231 irela[i].r_offset = irel[i].r_offset;
2232 irela[i].r_info = irel[i].r_info;
2233 irela[i].r_addend = 0;
2237 else
2239 Elf_External_Rela *erela;
2240 Elf_External_Rela *erelaend;
2241 Elf_Internal_Rela *irela;
2243 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2245 erela = (Elf_External_Rela *) external_relocs;
2246 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2247 irela = internal_relocs;
2248 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2250 if (bed->s->swap_reloca_in)
2251 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2252 else
2253 elf_swap_reloca_in (abfd, erela, irela);
2257 return true;
2260 /* Read and swap the relocs for a section O. They may have been
2261 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2262 not NULL, they are used as buffers to read into. They are known to
2263 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2264 the return value is allocated using either malloc or bfd_alloc,
2265 according to the KEEP_MEMORY argument. If O has two relocation
2266 sections (both REL and RELA relocations), then the REL_HDR
2267 relocations will appear first in INTERNAL_RELOCS, followed by the
2268 REL_HDR2 relocations. */
2270 Elf_Internal_Rela *
2271 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2272 keep_memory)
2273 bfd *abfd;
2274 asection *o;
2275 PTR external_relocs;
2276 Elf_Internal_Rela *internal_relocs;
2277 boolean keep_memory;
2279 Elf_Internal_Shdr *rel_hdr;
2280 PTR alloc1 = NULL;
2281 Elf_Internal_Rela *alloc2 = NULL;
2282 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2284 if (elf_section_data (o)->relocs != NULL)
2285 return elf_section_data (o)->relocs;
2287 if (o->reloc_count == 0)
2288 return NULL;
2290 rel_hdr = &elf_section_data (o)->rel_hdr;
2292 if (internal_relocs == NULL)
2294 size_t size;
2296 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2297 * sizeof (Elf_Internal_Rela));
2298 if (keep_memory)
2299 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2300 else
2301 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2302 if (internal_relocs == NULL)
2303 goto error_return;
2306 if (external_relocs == NULL)
2308 size_t size = (size_t) rel_hdr->sh_size;
2310 if (elf_section_data (o)->rel_hdr2)
2311 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2312 alloc1 = (PTR) bfd_malloc (size);
2313 if (alloc1 == NULL)
2314 goto error_return;
2315 external_relocs = alloc1;
2318 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2319 external_relocs,
2320 internal_relocs))
2321 goto error_return;
2322 if (!elf_link_read_relocs_from_section
2323 (abfd,
2324 elf_section_data (o)->rel_hdr2,
2325 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2326 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2327 * bed->s->int_rels_per_ext_rel)))
2328 goto error_return;
2330 /* Cache the results for next time, if we can. */
2331 if (keep_memory)
2332 elf_section_data (o)->relocs = internal_relocs;
2334 if (alloc1 != NULL)
2335 free (alloc1);
2337 /* Don't free alloc2, since if it was allocated we are passing it
2338 back (under the name of internal_relocs). */
2340 return internal_relocs;
2342 error_return:
2343 if (alloc1 != NULL)
2344 free (alloc1);
2345 if (alloc2 != NULL)
2346 free (alloc2);
2347 return NULL;
2351 /* Record an assignment to a symbol made by a linker script. We need
2352 this in case some dynamic object refers to this symbol. */
2354 /*ARGSUSED*/
2355 boolean
2356 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2357 bfd *output_bfd ATTRIBUTE_UNUSED;
2358 struct bfd_link_info *info;
2359 const char *name;
2360 boolean provide;
2362 struct elf_link_hash_entry *h;
2364 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2365 return true;
2367 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2368 if (h == NULL)
2369 return false;
2371 if (h->root.type == bfd_link_hash_new)
2372 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2374 /* If this symbol is being provided by the linker script, and it is
2375 currently defined by a dynamic object, but not by a regular
2376 object, then mark it as undefined so that the generic linker will
2377 force the correct value. */
2378 if (provide
2379 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2380 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2381 h->root.type = bfd_link_hash_undefined;
2383 /* If this symbol is not being provided by the linker script, and it is
2384 currently defined by a dynamic object, but not by a regular object,
2385 then clear out any version information because the symbol will not be
2386 associated with the dynamic object any more. */
2387 if (!provide
2388 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2389 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2390 h->verinfo.verdef = NULL;
2392 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2394 /* When possible, keep the original type of the symbol */
2395 if (h->type == STT_NOTYPE)
2396 h->type = STT_OBJECT;
2398 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2399 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2400 || info->shared)
2401 && h->dynindx == -1)
2403 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2404 return false;
2406 /* If this is a weak defined symbol, and we know a corresponding
2407 real symbol from the same dynamic object, make sure the real
2408 symbol is also made into a dynamic symbol. */
2409 if (h->weakdef != NULL
2410 && h->weakdef->dynindx == -1)
2412 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2413 return false;
2417 return true;
2420 /* This structure is used to pass information to
2421 elf_link_assign_sym_version. */
2423 struct elf_assign_sym_version_info
2425 /* Output BFD. */
2426 bfd *output_bfd;
2427 /* General link information. */
2428 struct bfd_link_info *info;
2429 /* Version tree. */
2430 struct bfd_elf_version_tree *verdefs;
2431 /* Whether we are exporting all dynamic symbols. */
2432 boolean export_dynamic;
2433 /* Whether we had a failure. */
2434 boolean failed;
2437 /* This structure is used to pass information to
2438 elf_link_find_version_dependencies. */
2440 struct elf_find_verdep_info
2442 /* Output BFD. */
2443 bfd *output_bfd;
2444 /* General link information. */
2445 struct bfd_link_info *info;
2446 /* The number of dependencies. */
2447 unsigned int vers;
2448 /* Whether we had a failure. */
2449 boolean failed;
2452 /* Array used to determine the number of hash table buckets to use
2453 based on the number of symbols there are. If there are fewer than
2454 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2455 fewer than 37 we use 17 buckets, and so forth. We never use more
2456 than 32771 buckets. */
2458 static const size_t elf_buckets[] =
2460 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2461 16411, 32771, 0
2464 /* Compute bucket count for hashing table. We do not use a static set
2465 of possible tables sizes anymore. Instead we determine for all
2466 possible reasonable sizes of the table the outcome (i.e., the
2467 number of collisions etc) and choose the best solution. The
2468 weighting functions are not too simple to allow the table to grow
2469 without bounds. Instead one of the weighting factors is the size.
2470 Therefore the result is always a good payoff between few collisions
2471 (= short chain lengths) and table size. */
2472 static size_t
2473 compute_bucket_count (info)
2474 struct bfd_link_info *info;
2476 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2477 size_t best_size = 0;
2478 unsigned long int *hashcodes;
2479 unsigned long int *hashcodesp;
2480 unsigned long int i;
2482 /* Compute the hash values for all exported symbols. At the same
2483 time store the values in an array so that we could use them for
2484 optimizations. */
2485 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2486 * sizeof (unsigned long int));
2487 if (hashcodes == NULL)
2488 return 0;
2489 hashcodesp = hashcodes;
2491 /* Put all hash values in HASHCODES. */
2492 elf_link_hash_traverse (elf_hash_table (info),
2493 elf_collect_hash_codes, &hashcodesp);
2495 /* We have a problem here. The following code to optimize the table
2496 size requires an integer type with more the 32 bits. If
2497 BFD_HOST_U_64_BIT is set we know about such a type. */
2498 #ifdef BFD_HOST_U_64_BIT
2499 if (info->optimize == true)
2501 unsigned long int nsyms = hashcodesp - hashcodes;
2502 size_t minsize;
2503 size_t maxsize;
2504 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2505 unsigned long int *counts ;
2507 /* Possible optimization parameters: if we have NSYMS symbols we say
2508 that the hashing table must at least have NSYMS/4 and at most
2509 2*NSYMS buckets. */
2510 minsize = nsyms / 4;
2511 if (minsize == 0)
2512 minsize = 1;
2513 best_size = maxsize = nsyms * 2;
2515 /* Create array where we count the collisions in. We must use bfd_malloc
2516 since the size could be large. */
2517 counts = (unsigned long int *) bfd_malloc (maxsize
2518 * sizeof (unsigned long int));
2519 if (counts == NULL)
2521 free (hashcodes);
2522 return 0;
2525 /* Compute the "optimal" size for the hash table. The criteria is a
2526 minimal chain length. The minor criteria is (of course) the size
2527 of the table. */
2528 for (i = minsize; i < maxsize; ++i)
2530 /* Walk through the array of hashcodes and count the collisions. */
2531 BFD_HOST_U_64_BIT max;
2532 unsigned long int j;
2533 unsigned long int fact;
2535 memset (counts, '\0', i * sizeof (unsigned long int));
2537 /* Determine how often each hash bucket is used. */
2538 for (j = 0; j < nsyms; ++j)
2539 ++counts[hashcodes[j] % i];
2541 /* For the weight function we need some information about the
2542 pagesize on the target. This is information need not be 100%
2543 accurate. Since this information is not available (so far) we
2544 define it here to a reasonable default value. If it is crucial
2545 to have a better value some day simply define this value. */
2546 # ifndef BFD_TARGET_PAGESIZE
2547 # define BFD_TARGET_PAGESIZE (4096)
2548 # endif
2550 /* We in any case need 2 + NSYMS entries for the size values and
2551 the chains. */
2552 max = (2 + nsyms) * (ARCH_SIZE / 8);
2554 # if 1
2555 /* Variant 1: optimize for short chains. We add the squares
2556 of all the chain lengths (which favous many small chain
2557 over a few long chains). */
2558 for (j = 0; j < i; ++j)
2559 max += counts[j] * counts[j];
2561 /* This adds penalties for the overall size of the table. */
2562 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2563 max *= fact * fact;
2564 # else
2565 /* Variant 2: Optimize a lot more for small table. Here we
2566 also add squares of the size but we also add penalties for
2567 empty slots (the +1 term). */
2568 for (j = 0; j < i; ++j)
2569 max += (1 + counts[j]) * (1 + counts[j]);
2571 /* The overall size of the table is considered, but not as
2572 strong as in variant 1, where it is squared. */
2573 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2574 max *= fact;
2575 # endif
2577 /* Compare with current best results. */
2578 if (max < best_chlen)
2580 best_chlen = max;
2581 best_size = i;
2585 free (counts);
2587 else
2588 #endif /* defined (BFD_HOST_U_64_BIT) */
2590 /* This is the fallback solution if no 64bit type is available or if we
2591 are not supposed to spend much time on optimizations. We select the
2592 bucket count using a fixed set of numbers. */
2593 for (i = 0; elf_buckets[i] != 0; i++)
2595 best_size = elf_buckets[i];
2596 if (dynsymcount < elf_buckets[i + 1])
2597 break;
2601 /* Free the arrays we needed. */
2602 free (hashcodes);
2604 return best_size;
2607 /* Set up the sizes and contents of the ELF dynamic sections. This is
2608 called by the ELF linker emulation before_allocation routine. We
2609 must set the sizes of the sections before the linker sets the
2610 addresses of the various sections. */
2612 boolean
2613 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2614 export_dynamic, filter_shlib,
2615 auxiliary_filters, info, sinterpptr,
2616 verdefs)
2617 bfd *output_bfd;
2618 const char *soname;
2619 const char *rpath;
2620 boolean export_dynamic;
2621 const char *filter_shlib;
2622 const char * const *auxiliary_filters;
2623 struct bfd_link_info *info;
2624 asection **sinterpptr;
2625 struct bfd_elf_version_tree *verdefs;
2627 bfd_size_type soname_indx;
2628 bfd *dynobj;
2629 struct elf_backend_data *bed;
2630 struct elf_assign_sym_version_info asvinfo;
2632 *sinterpptr = NULL;
2634 soname_indx = (bfd_size_type) -1;
2636 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2637 return true;
2639 /* The backend may have to create some sections regardless of whether
2640 we're dynamic or not. */
2641 bed = get_elf_backend_data (output_bfd);
2642 if (bed->elf_backend_always_size_sections
2643 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2644 return false;
2646 dynobj = elf_hash_table (info)->dynobj;
2648 /* If there were no dynamic objects in the link, there is nothing to
2649 do here. */
2650 if (dynobj == NULL)
2651 return true;
2653 /* If we are supposed to export all symbols into the dynamic symbol
2654 table (this is not the normal case), then do so. */
2655 if (export_dynamic)
2657 struct elf_info_failed eif;
2659 eif.failed = false;
2660 eif.info = info;
2661 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2662 (PTR) &eif);
2663 if (eif.failed)
2664 return false;
2667 if (elf_hash_table (info)->dynamic_sections_created)
2669 struct elf_info_failed eif;
2670 struct elf_link_hash_entry *h;
2671 bfd_size_type strsize;
2673 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2674 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2676 if (soname != NULL)
2678 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2679 soname, true, true);
2680 if (soname_indx == (bfd_size_type) -1
2681 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2682 return false;
2685 if (info->symbolic)
2687 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2688 return false;
2691 if (rpath != NULL)
2693 bfd_size_type indx;
2695 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2696 true, true);
2697 if (indx == (bfd_size_type) -1
2698 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2699 return false;
2702 if (filter_shlib != NULL)
2704 bfd_size_type indx;
2706 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2707 filter_shlib, true, true);
2708 if (indx == (bfd_size_type) -1
2709 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2710 return false;
2713 if (auxiliary_filters != NULL)
2715 const char * const *p;
2717 for (p = auxiliary_filters; *p != NULL; p++)
2719 bfd_size_type indx;
2721 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2722 *p, true, true);
2723 if (indx == (bfd_size_type) -1
2724 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2725 return false;
2729 /* Attach all the symbols to their version information. */
2730 asvinfo.output_bfd = output_bfd;
2731 asvinfo.info = info;
2732 asvinfo.verdefs = verdefs;
2733 asvinfo.export_dynamic = export_dynamic;
2734 asvinfo.failed = false;
2736 elf_link_hash_traverse (elf_hash_table (info),
2737 elf_link_assign_sym_version,
2738 (PTR) &asvinfo);
2739 if (asvinfo.failed)
2740 return false;
2742 /* Find all symbols which were defined in a dynamic object and make
2743 the backend pick a reasonable value for them. */
2744 eif.failed = false;
2745 eif.info = info;
2746 elf_link_hash_traverse (elf_hash_table (info),
2747 elf_adjust_dynamic_symbol,
2748 (PTR) &eif);
2749 if (eif.failed)
2750 return false;
2752 /* Add some entries to the .dynamic section. We fill in some of the
2753 values later, in elf_bfd_final_link, but we must add the entries
2754 now so that we know the final size of the .dynamic section. */
2756 /* If there are initialization and/or finalization functions to
2757 call then add the corresponding DT_INIT/DT_FINI entries. */
2758 h = (info->init_function
2759 ? elf_link_hash_lookup (elf_hash_table (info),
2760 info->init_function, false,
2761 false, false)
2762 : NULL);
2763 if (h != NULL
2764 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2765 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2767 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2768 return false;
2770 h = (info->fini_function
2771 ? elf_link_hash_lookup (elf_hash_table (info),
2772 info->fini_function, false,
2773 false, false)
2774 : NULL);
2775 if (h != NULL
2776 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2777 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2779 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2780 return false;
2783 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2784 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2785 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2786 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2787 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2788 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2789 sizeof (Elf_External_Sym)))
2790 return false;
2793 /* The backend must work out the sizes of all the other dynamic
2794 sections. */
2795 if (bed->elf_backend_size_dynamic_sections
2796 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2797 return false;
2799 if (elf_hash_table (info)->dynamic_sections_created)
2801 size_t dynsymcount;
2802 asection *s;
2803 size_t bucketcount = 0;
2804 Elf_Internal_Sym isym;
2805 size_t hash_entry_size;
2807 /* Set up the version definition section. */
2808 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2809 BFD_ASSERT (s != NULL);
2811 /* We may have created additional version definitions if we are
2812 just linking a regular application. */
2813 verdefs = asvinfo.verdefs;
2815 if (verdefs == NULL)
2816 _bfd_strip_section_from_output (s);
2817 else
2819 unsigned int cdefs;
2820 bfd_size_type size;
2821 struct bfd_elf_version_tree *t;
2822 bfd_byte *p;
2823 Elf_Internal_Verdef def;
2824 Elf_Internal_Verdaux defaux;
2826 cdefs = 0;
2827 size = 0;
2829 /* Make space for the base version. */
2830 size += sizeof (Elf_External_Verdef);
2831 size += sizeof (Elf_External_Verdaux);
2832 ++cdefs;
2834 for (t = verdefs; t != NULL; t = t->next)
2836 struct bfd_elf_version_deps *n;
2838 size += sizeof (Elf_External_Verdef);
2839 size += sizeof (Elf_External_Verdaux);
2840 ++cdefs;
2842 for (n = t->deps; n != NULL; n = n->next)
2843 size += sizeof (Elf_External_Verdaux);
2846 s->_raw_size = size;
2847 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2848 if (s->contents == NULL && s->_raw_size != 0)
2849 return false;
2851 /* Fill in the version definition section. */
2853 p = s->contents;
2855 def.vd_version = VER_DEF_CURRENT;
2856 def.vd_flags = VER_FLG_BASE;
2857 def.vd_ndx = 1;
2858 def.vd_cnt = 1;
2859 def.vd_aux = sizeof (Elf_External_Verdef);
2860 def.vd_next = (sizeof (Elf_External_Verdef)
2861 + sizeof (Elf_External_Verdaux));
2863 if (soname_indx != (bfd_size_type) -1)
2865 def.vd_hash = bfd_elf_hash (soname);
2866 defaux.vda_name = soname_indx;
2868 else
2870 const char *name;
2871 bfd_size_type indx;
2873 name = output_bfd->filename;
2874 def.vd_hash = bfd_elf_hash (name);
2875 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2876 name, true, false);
2877 if (indx == (bfd_size_type) -1)
2878 return false;
2879 defaux.vda_name = indx;
2881 defaux.vda_next = 0;
2883 _bfd_elf_swap_verdef_out (output_bfd, &def,
2884 (Elf_External_Verdef *)p);
2885 p += sizeof (Elf_External_Verdef);
2886 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2887 (Elf_External_Verdaux *) p);
2888 p += sizeof (Elf_External_Verdaux);
2890 for (t = verdefs; t != NULL; t = t->next)
2892 unsigned int cdeps;
2893 struct bfd_elf_version_deps *n;
2894 struct elf_link_hash_entry *h;
2896 cdeps = 0;
2897 for (n = t->deps; n != NULL; n = n->next)
2898 ++cdeps;
2900 /* Add a symbol representing this version. */
2901 h = NULL;
2902 if (! (_bfd_generic_link_add_one_symbol
2903 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
2904 (bfd_vma) 0, (const char *) NULL, false,
2905 get_elf_backend_data (dynobj)->collect,
2906 (struct bfd_link_hash_entry **) &h)))
2907 return false;
2908 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
2909 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2910 h->type = STT_OBJECT;
2911 h->verinfo.vertree = t;
2913 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2914 return false;
2916 def.vd_version = VER_DEF_CURRENT;
2917 def.vd_flags = 0;
2918 if (t->globals == NULL && t->locals == NULL && ! t->used)
2919 def.vd_flags |= VER_FLG_WEAK;
2920 def.vd_ndx = t->vernum + 1;
2921 def.vd_cnt = cdeps + 1;
2922 def.vd_hash = bfd_elf_hash (t->name);
2923 def.vd_aux = sizeof (Elf_External_Verdef);
2924 if (t->next != NULL)
2925 def.vd_next = (sizeof (Elf_External_Verdef)
2926 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
2927 else
2928 def.vd_next = 0;
2930 _bfd_elf_swap_verdef_out (output_bfd, &def,
2931 (Elf_External_Verdef *) p);
2932 p += sizeof (Elf_External_Verdef);
2934 defaux.vda_name = h->dynstr_index;
2935 if (t->deps == NULL)
2936 defaux.vda_next = 0;
2937 else
2938 defaux.vda_next = sizeof (Elf_External_Verdaux);
2939 t->name_indx = defaux.vda_name;
2941 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2942 (Elf_External_Verdaux *) p);
2943 p += sizeof (Elf_External_Verdaux);
2945 for (n = t->deps; n != NULL; n = n->next)
2947 if (n->version_needed == NULL)
2949 /* This can happen if there was an error in the
2950 version script. */
2951 defaux.vda_name = 0;
2953 else
2954 defaux.vda_name = n->version_needed->name_indx;
2955 if (n->next == NULL)
2956 defaux.vda_next = 0;
2957 else
2958 defaux.vda_next = sizeof (Elf_External_Verdaux);
2960 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2961 (Elf_External_Verdaux *) p);
2962 p += sizeof (Elf_External_Verdaux);
2966 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
2967 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
2968 return false;
2970 elf_tdata (output_bfd)->cverdefs = cdefs;
2973 /* Work out the size of the version reference section. */
2975 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
2976 BFD_ASSERT (s != NULL);
2978 struct elf_find_verdep_info sinfo;
2980 sinfo.output_bfd = output_bfd;
2981 sinfo.info = info;
2982 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
2983 if (sinfo.vers == 0)
2984 sinfo.vers = 1;
2985 sinfo.failed = false;
2987 elf_link_hash_traverse (elf_hash_table (info),
2988 elf_link_find_version_dependencies,
2989 (PTR) &sinfo);
2991 if (elf_tdata (output_bfd)->verref == NULL)
2992 _bfd_strip_section_from_output (s);
2993 else
2995 Elf_Internal_Verneed *t;
2996 unsigned int size;
2997 unsigned int crefs;
2998 bfd_byte *p;
3000 /* Build the version definition section. */
3001 size = 0;
3002 crefs = 0;
3003 for (t = elf_tdata (output_bfd)->verref;
3004 t != NULL;
3005 t = t->vn_nextref)
3007 Elf_Internal_Vernaux *a;
3009 size += sizeof (Elf_External_Verneed);
3010 ++crefs;
3011 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3012 size += sizeof (Elf_External_Vernaux);
3015 s->_raw_size = size;
3016 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3017 if (s->contents == NULL)
3018 return false;
3020 p = s->contents;
3021 for (t = elf_tdata (output_bfd)->verref;
3022 t != NULL;
3023 t = t->vn_nextref)
3025 unsigned int caux;
3026 Elf_Internal_Vernaux *a;
3027 bfd_size_type indx;
3029 caux = 0;
3030 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3031 ++caux;
3033 t->vn_version = VER_NEED_CURRENT;
3034 t->vn_cnt = caux;
3035 if (elf_dt_name (t->vn_bfd) != NULL)
3036 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3037 elf_dt_name (t->vn_bfd),
3038 true, false);
3039 else
3040 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3041 t->vn_bfd->filename, true, false);
3042 if (indx == (bfd_size_type) -1)
3043 return false;
3044 t->vn_file = indx;
3045 t->vn_aux = sizeof (Elf_External_Verneed);
3046 if (t->vn_nextref == NULL)
3047 t->vn_next = 0;
3048 else
3049 t->vn_next = (sizeof (Elf_External_Verneed)
3050 + caux * sizeof (Elf_External_Vernaux));
3052 _bfd_elf_swap_verneed_out (output_bfd, t,
3053 (Elf_External_Verneed *) p);
3054 p += sizeof (Elf_External_Verneed);
3056 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3058 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3059 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3060 a->vna_nodename, true, false);
3061 if (indx == (bfd_size_type) -1)
3062 return false;
3063 a->vna_name = indx;
3064 if (a->vna_nextptr == NULL)
3065 a->vna_next = 0;
3066 else
3067 a->vna_next = sizeof (Elf_External_Vernaux);
3069 _bfd_elf_swap_vernaux_out (output_bfd, a,
3070 (Elf_External_Vernaux *) p);
3071 p += sizeof (Elf_External_Vernaux);
3075 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3076 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3077 return false;
3079 elf_tdata (output_bfd)->cverrefs = crefs;
3083 /* Assign dynsym indicies. In a shared library we generate a
3084 section symbol for each output section, which come first.
3085 Next come all of the back-end allocated local dynamic syms,
3086 followed by the rest of the global symbols. */
3088 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3090 /* Work out the size of the symbol version section. */
3091 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3092 BFD_ASSERT (s != NULL);
3093 if (dynsymcount == 0
3094 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3096 _bfd_strip_section_from_output (s);
3097 /* The DYNSYMCOUNT might have changed if we were going to
3098 output a dynamic symbol table entry for S. */
3099 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3101 else
3103 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3104 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3105 if (s->contents == NULL)
3106 return false;
3108 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3109 return false;
3112 /* Set the size of the .dynsym and .hash sections. We counted
3113 the number of dynamic symbols in elf_link_add_object_symbols.
3114 We will build the contents of .dynsym and .hash when we build
3115 the final symbol table, because until then we do not know the
3116 correct value to give the symbols. We built the .dynstr
3117 section as we went along in elf_link_add_object_symbols. */
3118 s = bfd_get_section_by_name (dynobj, ".dynsym");
3119 BFD_ASSERT (s != NULL);
3120 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3121 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3122 if (s->contents == NULL && s->_raw_size != 0)
3123 return false;
3125 /* The first entry in .dynsym is a dummy symbol. */
3126 isym.st_value = 0;
3127 isym.st_size = 0;
3128 isym.st_name = 0;
3129 isym.st_info = 0;
3130 isym.st_other = 0;
3131 isym.st_shndx = 0;
3132 elf_swap_symbol_out (output_bfd, &isym,
3133 (PTR) (Elf_External_Sym *) s->contents);
3135 /* Compute the size of the hashing table. As a side effect this
3136 computes the hash values for all the names we export. */
3137 bucketcount = compute_bucket_count (info);
3139 s = bfd_get_section_by_name (dynobj, ".hash");
3140 BFD_ASSERT (s != NULL);
3141 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3142 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3143 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3144 if (s->contents == NULL)
3145 return false;
3146 memset (s->contents, 0, (size_t) s->_raw_size);
3148 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3149 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3150 s->contents + hash_entry_size);
3152 elf_hash_table (info)->bucketcount = bucketcount;
3154 s = bfd_get_section_by_name (dynobj, ".dynstr");
3155 BFD_ASSERT (s != NULL);
3156 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3158 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3159 return false;
3162 return true;
3165 /* Fix up the flags for a symbol. This handles various cases which
3166 can only be fixed after all the input files are seen. This is
3167 currently called by both adjust_dynamic_symbol and
3168 assign_sym_version, which is unnecessary but perhaps more robust in
3169 the face of future changes. */
3171 static boolean
3172 elf_fix_symbol_flags (h, eif)
3173 struct elf_link_hash_entry *h;
3174 struct elf_info_failed *eif;
3176 /* If this symbol was mentioned in a non-ELF file, try to set
3177 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3178 permit a non-ELF file to correctly refer to a symbol defined in
3179 an ELF dynamic object. */
3180 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3182 if (h->root.type != bfd_link_hash_defined
3183 && h->root.type != bfd_link_hash_defweak)
3184 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3185 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3186 else
3188 if (h->root.u.def.section->owner != NULL
3189 && (bfd_get_flavour (h->root.u.def.section->owner)
3190 == bfd_target_elf_flavour))
3191 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3192 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3193 else
3194 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3197 if (h->dynindx == -1
3198 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3199 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3201 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3203 eif->failed = true;
3204 return false;
3208 else
3210 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3211 was first seen in a non-ELF file. Fortunately, if the symbol
3212 was first seen in an ELF file, we're probably OK unless the
3213 symbol was defined in a non-ELF file. Catch that case here.
3214 FIXME: We're still in trouble if the symbol was first seen in
3215 a dynamic object, and then later in a non-ELF regular object. */
3216 if ((h->root.type == bfd_link_hash_defined
3217 || h->root.type == bfd_link_hash_defweak)
3218 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3219 && (h->root.u.def.section->owner != NULL
3220 ? (bfd_get_flavour (h->root.u.def.section->owner)
3221 != bfd_target_elf_flavour)
3222 : (bfd_is_abs_section (h->root.u.def.section)
3223 && (h->elf_link_hash_flags
3224 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3225 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3228 /* If this is a final link, and the symbol was defined as a common
3229 symbol in a regular object file, and there was no definition in
3230 any dynamic object, then the linker will have allocated space for
3231 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3232 flag will not have been set. */
3233 if (h->root.type == bfd_link_hash_defined
3234 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3235 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3236 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3237 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3238 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3240 /* If -Bsymbolic was used (which means to bind references to global
3241 symbols to the definition within the shared object), and this
3242 symbol was defined in a regular object, then it actually doesn't
3243 need a PLT entry. */
3244 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3245 && eif->info->shared
3246 && eif->info->symbolic
3247 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3249 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3250 h->plt.offset = (bfd_vma) -1;
3253 /* If this is a weak defined symbol in a dynamic object, and we know
3254 the real definition in the dynamic object, copy interesting flags
3255 over to the real definition. */
3256 if (h->weakdef != NULL)
3258 struct elf_link_hash_entry *weakdef;
3260 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3261 || h->root.type == bfd_link_hash_defweak);
3262 weakdef = h->weakdef;
3263 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3264 || weakdef->root.type == bfd_link_hash_defweak);
3265 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3267 /* If the real definition is defined by a regular object file,
3268 don't do anything special. See the longer description in
3269 elf_adjust_dynamic_symbol, below. */
3270 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3271 h->weakdef = NULL;
3272 else
3273 weakdef->elf_link_hash_flags |=
3274 (h->elf_link_hash_flags
3275 & (ELF_LINK_HASH_REF_REGULAR
3276 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3277 | ELF_LINK_NON_GOT_REF));
3280 return true;
3283 /* Make the backend pick a good value for a dynamic symbol. This is
3284 called via elf_link_hash_traverse, and also calls itself
3285 recursively. */
3287 static boolean
3288 elf_adjust_dynamic_symbol (h, data)
3289 struct elf_link_hash_entry *h;
3290 PTR data;
3292 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3293 bfd *dynobj;
3294 struct elf_backend_data *bed;
3296 /* Ignore indirect symbols. These are added by the versioning code. */
3297 if (h->root.type == bfd_link_hash_indirect)
3298 return true;
3300 /* Fix the symbol flags. */
3301 if (! elf_fix_symbol_flags (h, eif))
3302 return false;
3304 /* If this symbol does not require a PLT entry, and it is not
3305 defined by a dynamic object, or is not referenced by a regular
3306 object, ignore it. We do have to handle a weak defined symbol,
3307 even if no regular object refers to it, if we decided to add it
3308 to the dynamic symbol table. FIXME: Do we normally need to worry
3309 about symbols which are defined by one dynamic object and
3310 referenced by another one? */
3311 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3312 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3313 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3314 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3315 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3317 h->plt.offset = (bfd_vma) -1;
3318 return true;
3321 /* If we've already adjusted this symbol, don't do it again. This
3322 can happen via a recursive call. */
3323 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3324 return true;
3326 /* Don't look at this symbol again. Note that we must set this
3327 after checking the above conditions, because we may look at a
3328 symbol once, decide not to do anything, and then get called
3329 recursively later after REF_REGULAR is set below. */
3330 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3332 /* If this is a weak definition, and we know a real definition, and
3333 the real symbol is not itself defined by a regular object file,
3334 then get a good value for the real definition. We handle the
3335 real symbol first, for the convenience of the backend routine.
3337 Note that there is a confusing case here. If the real definition
3338 is defined by a regular object file, we don't get the real symbol
3339 from the dynamic object, but we do get the weak symbol. If the
3340 processor backend uses a COPY reloc, then if some routine in the
3341 dynamic object changes the real symbol, we will not see that
3342 change in the corresponding weak symbol. This is the way other
3343 ELF linkers work as well, and seems to be a result of the shared
3344 library model.
3346 I will clarify this issue. Most SVR4 shared libraries define the
3347 variable _timezone and define timezone as a weak synonym. The
3348 tzset call changes _timezone. If you write
3349 extern int timezone;
3350 int _timezone = 5;
3351 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3352 you might expect that, since timezone is a synonym for _timezone,
3353 the same number will print both times. However, if the processor
3354 backend uses a COPY reloc, then actually timezone will be copied
3355 into your process image, and, since you define _timezone
3356 yourself, _timezone will not. Thus timezone and _timezone will
3357 wind up at different memory locations. The tzset call will set
3358 _timezone, leaving timezone unchanged. */
3360 if (h->weakdef != NULL)
3362 /* If we get to this point, we know there is an implicit
3363 reference by a regular object file via the weak symbol H.
3364 FIXME: Is this really true? What if the traversal finds
3365 H->WEAKDEF before it finds H? */
3366 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3368 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3369 return false;
3372 /* If a symbol has no type and no size and does not require a PLT
3373 entry, then we are probably about to do the wrong thing here: we
3374 are probably going to create a COPY reloc for an empty object.
3375 This case can arise when a shared object is built with assembly
3376 code, and the assembly code fails to set the symbol type. */
3377 if (h->size == 0
3378 && h->type == STT_NOTYPE
3379 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3380 (*_bfd_error_handler)
3381 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3382 h->root.root.string);
3384 dynobj = elf_hash_table (eif->info)->dynobj;
3385 bed = get_elf_backend_data (dynobj);
3386 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3388 eif->failed = true;
3389 return false;
3392 return true;
3395 /* This routine is used to export all defined symbols into the dynamic
3396 symbol table. It is called via elf_link_hash_traverse. */
3398 static boolean
3399 elf_export_symbol (h, data)
3400 struct elf_link_hash_entry *h;
3401 PTR data;
3403 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3405 /* Ignore indirect symbols. These are added by the versioning code. */
3406 if (h->root.type == bfd_link_hash_indirect)
3407 return true;
3409 if (h->dynindx == -1
3410 && (h->elf_link_hash_flags
3411 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3413 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3415 eif->failed = true;
3416 return false;
3420 return true;
3423 /* Look through the symbols which are defined in other shared
3424 libraries and referenced here. Update the list of version
3425 dependencies. This will be put into the .gnu.version_r section.
3426 This function is called via elf_link_hash_traverse. */
3428 static boolean
3429 elf_link_find_version_dependencies (h, data)
3430 struct elf_link_hash_entry *h;
3431 PTR data;
3433 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3434 Elf_Internal_Verneed *t;
3435 Elf_Internal_Vernaux *a;
3437 /* We only care about symbols defined in shared objects with version
3438 information. */
3439 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3440 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3441 || h->dynindx == -1
3442 || h->verinfo.verdef == NULL)
3443 return true;
3445 /* See if we already know about this version. */
3446 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3448 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3449 continue;
3451 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3452 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3453 return true;
3455 break;
3458 /* This is a new version. Add it to tree we are building. */
3460 if (t == NULL)
3462 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3463 if (t == NULL)
3465 rinfo->failed = true;
3466 return false;
3469 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3470 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3471 elf_tdata (rinfo->output_bfd)->verref = t;
3474 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3476 /* Note that we are copying a string pointer here, and testing it
3477 above. If bfd_elf_string_from_elf_section is ever changed to
3478 discard the string data when low in memory, this will have to be
3479 fixed. */
3480 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3482 a->vna_flags = h->verinfo.verdef->vd_flags;
3483 a->vna_nextptr = t->vn_auxptr;
3485 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3486 ++rinfo->vers;
3488 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3490 t->vn_auxptr = a;
3492 return true;
3495 /* Figure out appropriate versions for all the symbols. We may not
3496 have the version number script until we have read all of the input
3497 files, so until that point we don't know which symbols should be
3498 local. This function is called via elf_link_hash_traverse. */
3500 static boolean
3501 elf_link_assign_sym_version (h, data)
3502 struct elf_link_hash_entry *h;
3503 PTR data;
3505 struct elf_assign_sym_version_info *sinfo =
3506 (struct elf_assign_sym_version_info *) data;
3507 struct bfd_link_info *info = sinfo->info;
3508 struct elf_info_failed eif;
3509 char *p;
3511 /* Fix the symbol flags. */
3512 eif.failed = false;
3513 eif.info = info;
3514 if (! elf_fix_symbol_flags (h, &eif))
3516 if (eif.failed)
3517 sinfo->failed = true;
3518 return false;
3521 /* We only need version numbers for symbols defined in regular
3522 objects. */
3523 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3524 return true;
3526 p = strchr (h->root.root.string, ELF_VER_CHR);
3527 if (p != NULL && h->verinfo.vertree == NULL)
3529 struct bfd_elf_version_tree *t;
3530 boolean hidden;
3532 hidden = true;
3534 /* There are two consecutive ELF_VER_CHR characters if this is
3535 not a hidden symbol. */
3536 ++p;
3537 if (*p == ELF_VER_CHR)
3539 hidden = false;
3540 ++p;
3543 /* If there is no version string, we can just return out. */
3544 if (*p == '\0')
3546 if (hidden)
3547 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3548 return true;
3551 /* Look for the version. If we find it, it is no longer weak. */
3552 for (t = sinfo->verdefs; t != NULL; t = t->next)
3554 if (strcmp (t->name, p) == 0)
3556 int len;
3557 char *alc;
3558 struct bfd_elf_version_expr *d;
3560 len = p - h->root.root.string;
3561 alc = bfd_alloc (sinfo->output_bfd, len);
3562 if (alc == NULL)
3563 return false;
3564 strncpy (alc, h->root.root.string, len - 1);
3565 alc[len - 1] = '\0';
3566 if (alc[len - 2] == ELF_VER_CHR)
3567 alc[len - 2] = '\0';
3569 h->verinfo.vertree = t;
3570 t->used = true;
3571 d = NULL;
3573 if (t->globals != NULL)
3575 for (d = t->globals; d != NULL; d = d->next)
3576 if ((*d->match) (d, alc))
3577 break;
3580 /* See if there is anything to force this symbol to
3581 local scope. */
3582 if (d == NULL && t->locals != NULL)
3584 for (d = t->locals; d != NULL; d = d->next)
3586 if ((*d->match) (d, alc))
3588 if (h->dynindx != -1
3589 && info->shared
3590 && ! sinfo->export_dynamic)
3592 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3593 h->elf_link_hash_flags &=~
3594 ELF_LINK_HASH_NEEDS_PLT;
3595 h->dynindx = -1;
3596 h->plt.offset = (bfd_vma) -1;
3597 /* FIXME: The name of the symbol has
3598 already been recorded in the dynamic
3599 string table section. */
3602 break;
3607 bfd_release (sinfo->output_bfd, alc);
3608 break;
3612 /* If we are building an application, we need to create a
3613 version node for this version. */
3614 if (t == NULL && ! info->shared)
3616 struct bfd_elf_version_tree **pp;
3617 int version_index;
3619 /* If we aren't going to export this symbol, we don't need
3620 to worry about it. */
3621 if (h->dynindx == -1)
3622 return true;
3624 t = ((struct bfd_elf_version_tree *)
3625 bfd_alloc (sinfo->output_bfd, sizeof *t));
3626 if (t == NULL)
3628 sinfo->failed = true;
3629 return false;
3632 t->next = NULL;
3633 t->name = p;
3634 t->globals = NULL;
3635 t->locals = NULL;
3636 t->deps = NULL;
3637 t->name_indx = (unsigned int) -1;
3638 t->used = true;
3640 version_index = 1;
3641 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3642 ++version_index;
3643 t->vernum = version_index;
3645 *pp = t;
3647 h->verinfo.vertree = t;
3649 else if (t == NULL)
3651 /* We could not find the version for a symbol when
3652 generating a shared archive. Return an error. */
3653 (*_bfd_error_handler)
3654 (_("%s: undefined versioned symbol name %s"),
3655 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3656 bfd_set_error (bfd_error_bad_value);
3657 sinfo->failed = true;
3658 return false;
3661 if (hidden)
3662 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3665 /* If we don't have a version for this symbol, see if we can find
3666 something. */
3667 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3669 struct bfd_elf_version_tree *t;
3670 struct bfd_elf_version_tree *deflt;
3671 struct bfd_elf_version_expr *d;
3673 /* See if can find what version this symbol is in. If the
3674 symbol is supposed to be local, then don't actually register
3675 it. */
3676 deflt = NULL;
3677 for (t = sinfo->verdefs; t != NULL; t = t->next)
3679 if (t->globals != NULL)
3681 for (d = t->globals; d != NULL; d = d->next)
3683 if ((*d->match) (d, h->root.root.string))
3685 h->verinfo.vertree = t;
3686 break;
3690 if (d != NULL)
3691 break;
3694 if (t->locals != NULL)
3696 for (d = t->locals; d != NULL; d = d->next)
3698 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3699 deflt = t;
3700 else if ((*d->match) (d, h->root.root.string))
3702 h->verinfo.vertree = t;
3703 if (h->dynindx != -1
3704 && info->shared
3705 && ! sinfo->export_dynamic)
3707 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3708 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3709 h->dynindx = -1;
3710 h->plt.offset = (bfd_vma) -1;
3711 /* FIXME: The name of the symbol has already
3712 been recorded in the dynamic string table
3713 section. */
3715 break;
3719 if (d != NULL)
3720 break;
3724 if (deflt != NULL && h->verinfo.vertree == NULL)
3726 h->verinfo.vertree = deflt;
3727 if (h->dynindx != -1
3728 && info->shared
3729 && ! sinfo->export_dynamic)
3731 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3732 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3733 h->dynindx = -1;
3734 h->plt.offset = (bfd_vma) -1;
3735 /* FIXME: The name of the symbol has already been
3736 recorded in the dynamic string table section. */
3741 return true;
3744 /* Final phase of ELF linker. */
3746 /* A structure we use to avoid passing large numbers of arguments. */
3748 struct elf_final_link_info
3750 /* General link information. */
3751 struct bfd_link_info *info;
3752 /* Output BFD. */
3753 bfd *output_bfd;
3754 /* Symbol string table. */
3755 struct bfd_strtab_hash *symstrtab;
3756 /* .dynsym section. */
3757 asection *dynsym_sec;
3758 /* .hash section. */
3759 asection *hash_sec;
3760 /* symbol version section (.gnu.version). */
3761 asection *symver_sec;
3762 /* Buffer large enough to hold contents of any section. */
3763 bfd_byte *contents;
3764 /* Buffer large enough to hold external relocs of any section. */
3765 PTR external_relocs;
3766 /* Buffer large enough to hold internal relocs of any section. */
3767 Elf_Internal_Rela *internal_relocs;
3768 /* Buffer large enough to hold external local symbols of any input
3769 BFD. */
3770 Elf_External_Sym *external_syms;
3771 /* Buffer large enough to hold internal local symbols of any input
3772 BFD. */
3773 Elf_Internal_Sym *internal_syms;
3774 /* Array large enough to hold a symbol index for each local symbol
3775 of any input BFD. */
3776 long *indices;
3777 /* Array large enough to hold a section pointer for each local
3778 symbol of any input BFD. */
3779 asection **sections;
3780 /* Buffer to hold swapped out symbols. */
3781 Elf_External_Sym *symbuf;
3782 /* Number of swapped out symbols in buffer. */
3783 size_t symbuf_count;
3784 /* Number of symbols which fit in symbuf. */
3785 size_t symbuf_size;
3788 static boolean elf_link_output_sym
3789 PARAMS ((struct elf_final_link_info *, const char *,
3790 Elf_Internal_Sym *, asection *));
3791 static boolean elf_link_flush_output_syms
3792 PARAMS ((struct elf_final_link_info *));
3793 static boolean elf_link_output_extsym
3794 PARAMS ((struct elf_link_hash_entry *, PTR));
3795 static boolean elf_link_input_bfd
3796 PARAMS ((struct elf_final_link_info *, bfd *));
3797 static boolean elf_reloc_link_order
3798 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3799 struct bfd_link_order *));
3801 /* This struct is used to pass information to elf_link_output_extsym. */
3803 struct elf_outext_info
3805 boolean failed;
3806 boolean localsyms;
3807 struct elf_final_link_info *finfo;
3810 /* Compute the size of, and allocate space for, REL_HDR which is the
3811 section header for a section containing relocations for O. */
3813 static boolean
3814 elf_link_size_reloc_section (abfd, rel_hdr, o)
3815 bfd *abfd;
3816 Elf_Internal_Shdr *rel_hdr;
3817 asection *o;
3819 register struct elf_link_hash_entry **p, **pend;
3820 unsigned reloc_count;
3822 /* Figure out how many relocations there will be. */
3823 if (rel_hdr == &elf_section_data (o)->rel_hdr)
3824 reloc_count = elf_section_data (o)->rel_count;
3825 else
3826 reloc_count = elf_section_data (o)->rel_count2;
3828 /* That allows us to calculate the size of the section. */
3829 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
3831 /* The contents field must last into write_object_contents, so we
3832 allocate it with bfd_alloc rather than malloc. */
3833 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3834 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3835 return false;
3837 /* We only allocate one set of hash entries, so we only do it the
3838 first time we are called. */
3839 if (elf_section_data (o)->rel_hashes == NULL)
3841 p = ((struct elf_link_hash_entry **)
3842 bfd_malloc (o->reloc_count
3843 * sizeof (struct elf_link_hash_entry *)));
3844 if (p == NULL && o->reloc_count != 0)
3845 return false;
3847 elf_section_data (o)->rel_hashes = p;
3848 pend = p + o->reloc_count;
3849 for (; p < pend; p++)
3850 *p = NULL;
3853 return true;
3856 /* When performing a relocateable link, the input relocations are
3857 preserved. But, if they reference global symbols, the indices
3858 referenced must be updated. Update all the relocations in
3859 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
3861 static void
3862 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
3863 bfd *abfd;
3864 Elf_Internal_Shdr *rel_hdr;
3865 unsigned int count;
3866 struct elf_link_hash_entry **rel_hash;
3868 unsigned int i;
3870 for (i = 0; i < count; i++, rel_hash++)
3872 if (*rel_hash == NULL)
3873 continue;
3875 BFD_ASSERT ((*rel_hash)->indx >= 0);
3877 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3879 Elf_External_Rel *erel;
3880 Elf_Internal_Rel irel;
3882 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3883 elf_swap_reloc_in (abfd, erel, &irel);
3884 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3885 ELF_R_TYPE (irel.r_info));
3886 elf_swap_reloc_out (abfd, &irel, erel);
3888 else
3890 Elf_External_Rela *erela;
3891 Elf_Internal_Rela irela;
3893 BFD_ASSERT (rel_hdr->sh_entsize
3894 == sizeof (Elf_External_Rela));
3896 erela = (Elf_External_Rela *) rel_hdr->contents + i;
3897 elf_swap_reloca_in (abfd, erela, &irela);
3898 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
3899 ELF_R_TYPE (irela.r_info));
3900 elf_swap_reloca_out (abfd, &irela, erela);
3905 /* Do the final step of an ELF link. */
3907 boolean
3908 elf_bfd_final_link (abfd, info)
3909 bfd *abfd;
3910 struct bfd_link_info *info;
3912 boolean dynamic;
3913 bfd *dynobj;
3914 struct elf_final_link_info finfo;
3915 register asection *o;
3916 register struct bfd_link_order *p;
3917 register bfd *sub;
3918 size_t max_contents_size;
3919 size_t max_external_reloc_size;
3920 size_t max_internal_reloc_count;
3921 size_t max_sym_count;
3922 file_ptr off;
3923 Elf_Internal_Sym elfsym;
3924 unsigned int i;
3925 Elf_Internal_Shdr *symtab_hdr;
3926 Elf_Internal_Shdr *symstrtab_hdr;
3927 struct elf_backend_data *bed = get_elf_backend_data (abfd);
3928 struct elf_outext_info eoinfo;
3930 if (info->shared)
3931 abfd->flags |= DYNAMIC;
3933 dynamic = elf_hash_table (info)->dynamic_sections_created;
3934 dynobj = elf_hash_table (info)->dynobj;
3936 finfo.info = info;
3937 finfo.output_bfd = abfd;
3938 finfo.symstrtab = elf_stringtab_init ();
3939 if (finfo.symstrtab == NULL)
3940 return false;
3942 if (! dynamic)
3944 finfo.dynsym_sec = NULL;
3945 finfo.hash_sec = NULL;
3946 finfo.symver_sec = NULL;
3948 else
3950 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
3951 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
3952 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
3953 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
3954 /* Note that it is OK if symver_sec is NULL. */
3957 finfo.contents = NULL;
3958 finfo.external_relocs = NULL;
3959 finfo.internal_relocs = NULL;
3960 finfo.external_syms = NULL;
3961 finfo.internal_syms = NULL;
3962 finfo.indices = NULL;
3963 finfo.sections = NULL;
3964 finfo.symbuf = NULL;
3965 finfo.symbuf_count = 0;
3967 /* Count up the number of relocations we will output for each output
3968 section, so that we know the sizes of the reloc sections. We
3969 also figure out some maximum sizes. */
3970 max_contents_size = 0;
3971 max_external_reloc_size = 0;
3972 max_internal_reloc_count = 0;
3973 max_sym_count = 0;
3974 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
3976 o->reloc_count = 0;
3978 for (p = o->link_order_head; p != NULL; p = p->next)
3980 if (p->type == bfd_section_reloc_link_order
3981 || p->type == bfd_symbol_reloc_link_order)
3982 ++o->reloc_count;
3983 else if (p->type == bfd_indirect_link_order)
3985 asection *sec;
3987 sec = p->u.indirect.section;
3989 /* Mark all sections which are to be included in the
3990 link. This will normally be every section. We need
3991 to do this so that we can identify any sections which
3992 the linker has decided to not include. */
3993 sec->linker_mark = true;
3995 if (info->relocateable)
3996 o->reloc_count += sec->reloc_count;
3998 if (sec->_raw_size > max_contents_size)
3999 max_contents_size = sec->_raw_size;
4000 if (sec->_cooked_size > max_contents_size)
4001 max_contents_size = sec->_cooked_size;
4003 /* We are interested in just local symbols, not all
4004 symbols. */
4005 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4006 && (sec->owner->flags & DYNAMIC) == 0)
4008 size_t sym_count;
4010 if (elf_bad_symtab (sec->owner))
4011 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4012 / sizeof (Elf_External_Sym));
4013 else
4014 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4016 if (sym_count > max_sym_count)
4017 max_sym_count = sym_count;
4019 if ((sec->flags & SEC_RELOC) != 0)
4021 size_t ext_size;
4023 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4024 if (ext_size > max_external_reloc_size)
4025 max_external_reloc_size = ext_size;
4026 if (sec->reloc_count > max_internal_reloc_count)
4027 max_internal_reloc_count = sec->reloc_count;
4033 if (o->reloc_count > 0)
4034 o->flags |= SEC_RELOC;
4035 else
4037 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4038 set it (this is probably a bug) and if it is set
4039 assign_section_numbers will create a reloc section. */
4040 o->flags &=~ SEC_RELOC;
4043 /* If the SEC_ALLOC flag is not set, force the section VMA to
4044 zero. This is done in elf_fake_sections as well, but forcing
4045 the VMA to 0 here will ensure that relocs against these
4046 sections are handled correctly. */
4047 if ((o->flags & SEC_ALLOC) == 0
4048 && ! o->user_set_vma)
4049 o->vma = 0;
4052 /* Figure out the file positions for everything but the symbol table
4053 and the relocs. We set symcount to force assign_section_numbers
4054 to create a symbol table. */
4055 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4056 BFD_ASSERT (! abfd->output_has_begun);
4057 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4058 goto error_return;
4060 /* Figure out how many relocations we will have in each section.
4061 Just using RELOC_COUNT isn't good enough since that doesn't
4062 maintain a separate value for REL vs. RELA relocations. */
4063 if (info->relocateable)
4064 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4065 for (o = sub->sections; o != NULL; o = o->next)
4067 asection *output_section;
4069 if (! o->linker_mark)
4071 /* This section was omitted from the link. */
4072 continue;
4075 output_section = o->output_section;
4077 if (output_section != NULL
4078 && (o->flags & SEC_RELOC) != 0)
4080 struct bfd_elf_section_data *esdi
4081 = elf_section_data (o);
4082 struct bfd_elf_section_data *esdo
4083 = elf_section_data (output_section);
4084 unsigned int *rel_count;
4085 unsigned int *rel_count2;
4087 /* We must be careful to add the relocation froms the
4088 input section to the right output count. */
4089 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4091 rel_count = &esdo->rel_count;
4092 rel_count2 = &esdo->rel_count2;
4094 else
4096 rel_count = &esdo->rel_count2;
4097 rel_count2 = &esdo->rel_count;
4100 *rel_count += (esdi->rel_hdr.sh_size
4101 / esdi->rel_hdr.sh_entsize);
4102 if (esdi->rel_hdr2)
4103 *rel_count2 += (esdi->rel_hdr2->sh_size
4104 / esdi->rel_hdr2->sh_entsize);
4108 /* That created the reloc sections. Set their sizes, and assign
4109 them file positions, and allocate some buffers. */
4110 for (o = abfd->sections; o != NULL; o = o->next)
4112 if ((o->flags & SEC_RELOC) != 0)
4114 if (!elf_link_size_reloc_section (abfd,
4115 &elf_section_data (o)->rel_hdr,
4117 goto error_return;
4119 if (elf_section_data (o)->rel_hdr2
4120 && !elf_link_size_reloc_section (abfd,
4121 elf_section_data (o)->rel_hdr2,
4123 goto error_return;
4126 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4127 to count upwards while actually outputting the relocations. */
4128 elf_section_data (o)->rel_count = 0;
4129 elf_section_data (o)->rel_count2 = 0;
4132 _bfd_elf_assign_file_positions_for_relocs (abfd);
4134 /* We have now assigned file positions for all the sections except
4135 .symtab and .strtab. We start the .symtab section at the current
4136 file position, and write directly to it. We build the .strtab
4137 section in memory. */
4138 bfd_get_symcount (abfd) = 0;
4139 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4140 /* sh_name is set in prep_headers. */
4141 symtab_hdr->sh_type = SHT_SYMTAB;
4142 symtab_hdr->sh_flags = 0;
4143 symtab_hdr->sh_addr = 0;
4144 symtab_hdr->sh_size = 0;
4145 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4146 /* sh_link is set in assign_section_numbers. */
4147 /* sh_info is set below. */
4148 /* sh_offset is set just below. */
4149 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4151 off = elf_tdata (abfd)->next_file_pos;
4152 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4154 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4155 incorrect. We do not yet know the size of the .symtab section.
4156 We correct next_file_pos below, after we do know the size. */
4158 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4159 continuously seeking to the right position in the file. */
4160 if (! info->keep_memory || max_sym_count < 20)
4161 finfo.symbuf_size = 20;
4162 else
4163 finfo.symbuf_size = max_sym_count;
4164 finfo.symbuf = ((Elf_External_Sym *)
4165 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4166 if (finfo.symbuf == NULL)
4167 goto error_return;
4169 /* Start writing out the symbol table. The first symbol is always a
4170 dummy symbol. */
4171 if (info->strip != strip_all || info->relocateable)
4173 elfsym.st_value = 0;
4174 elfsym.st_size = 0;
4175 elfsym.st_info = 0;
4176 elfsym.st_other = 0;
4177 elfsym.st_shndx = SHN_UNDEF;
4178 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4179 &elfsym, bfd_und_section_ptr))
4180 goto error_return;
4183 #if 0
4184 /* Some standard ELF linkers do this, but we don't because it causes
4185 bootstrap comparison failures. */
4186 /* Output a file symbol for the output file as the second symbol.
4187 We output this even if we are discarding local symbols, although
4188 I'm not sure if this is correct. */
4189 elfsym.st_value = 0;
4190 elfsym.st_size = 0;
4191 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4192 elfsym.st_other = 0;
4193 elfsym.st_shndx = SHN_ABS;
4194 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4195 &elfsym, bfd_abs_section_ptr))
4196 goto error_return;
4197 #endif
4199 /* Output a symbol for each section. We output these even if we are
4200 discarding local symbols, since they are used for relocs. These
4201 symbols have no names. We store the index of each one in the
4202 index field of the section, so that we can find it again when
4203 outputting relocs. */
4204 if (info->strip != strip_all || info->relocateable)
4206 elfsym.st_size = 0;
4207 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4208 elfsym.st_other = 0;
4209 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4211 o = section_from_elf_index (abfd, i);
4212 if (o != NULL)
4213 o->target_index = bfd_get_symcount (abfd);
4214 elfsym.st_shndx = i;
4215 if (info->relocateable || o == NULL)
4216 elfsym.st_value = 0;
4217 else
4218 elfsym.st_value = o->vma;
4219 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4220 &elfsym, o))
4221 goto error_return;
4225 /* Allocate some memory to hold information read in from the input
4226 files. */
4227 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4228 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4229 finfo.internal_relocs = ((Elf_Internal_Rela *)
4230 bfd_malloc (max_internal_reloc_count
4231 * sizeof (Elf_Internal_Rela)
4232 * bed->s->int_rels_per_ext_rel));
4233 finfo.external_syms = ((Elf_External_Sym *)
4234 bfd_malloc (max_sym_count
4235 * sizeof (Elf_External_Sym)));
4236 finfo.internal_syms = ((Elf_Internal_Sym *)
4237 bfd_malloc (max_sym_count
4238 * sizeof (Elf_Internal_Sym)));
4239 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4240 finfo.sections = ((asection **)
4241 bfd_malloc (max_sym_count * sizeof (asection *)));
4242 if ((finfo.contents == NULL && max_contents_size != 0)
4243 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4244 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4245 || (finfo.external_syms == NULL && max_sym_count != 0)
4246 || (finfo.internal_syms == NULL && max_sym_count != 0)
4247 || (finfo.indices == NULL && max_sym_count != 0)
4248 || (finfo.sections == NULL && max_sym_count != 0))
4249 goto error_return;
4251 /* Since ELF permits relocations to be against local symbols, we
4252 must have the local symbols available when we do the relocations.
4253 Since we would rather only read the local symbols once, and we
4254 would rather not keep them in memory, we handle all the
4255 relocations for a single input file at the same time.
4257 Unfortunately, there is no way to know the total number of local
4258 symbols until we have seen all of them, and the local symbol
4259 indices precede the global symbol indices. This means that when
4260 we are generating relocateable output, and we see a reloc against
4261 a global symbol, we can not know the symbol index until we have
4262 finished examining all the local symbols to see which ones we are
4263 going to output. To deal with this, we keep the relocations in
4264 memory, and don't output them until the end of the link. This is
4265 an unfortunate waste of memory, but I don't see a good way around
4266 it. Fortunately, it only happens when performing a relocateable
4267 link, which is not the common case. FIXME: If keep_memory is set
4268 we could write the relocs out and then read them again; I don't
4269 know how bad the memory loss will be. */
4271 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4272 sub->output_has_begun = false;
4273 for (o = abfd->sections; o != NULL; o = o->next)
4275 for (p = o->link_order_head; p != NULL; p = p->next)
4277 if (p->type == bfd_indirect_link_order
4278 && (bfd_get_flavour (p->u.indirect.section->owner)
4279 == bfd_target_elf_flavour))
4281 sub = p->u.indirect.section->owner;
4282 if (! sub->output_has_begun)
4284 if (! elf_link_input_bfd (&finfo, sub))
4285 goto error_return;
4286 sub->output_has_begun = true;
4289 else if (p->type == bfd_section_reloc_link_order
4290 || p->type == bfd_symbol_reloc_link_order)
4292 if (! elf_reloc_link_order (abfd, info, o, p))
4293 goto error_return;
4295 else
4297 if (! _bfd_default_link_order (abfd, info, o, p))
4298 goto error_return;
4303 /* That wrote out all the local symbols. Finish up the symbol table
4304 with the global symbols. */
4306 if (info->strip != strip_all && info->shared)
4308 /* Output any global symbols that got converted to local in a
4309 version script. We do this in a separate step since ELF
4310 requires all local symbols to appear prior to any global
4311 symbols. FIXME: We should only do this if some global
4312 symbols were, in fact, converted to become local. FIXME:
4313 Will this work correctly with the Irix 5 linker? */
4314 eoinfo.failed = false;
4315 eoinfo.finfo = &finfo;
4316 eoinfo.localsyms = true;
4317 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4318 (PTR) &eoinfo);
4319 if (eoinfo.failed)
4320 return false;
4323 /* The sh_info field records the index of the first non local symbol. */
4324 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4326 if (dynamic)
4328 Elf_Internal_Sym sym;
4329 Elf_External_Sym *dynsym =
4330 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4331 unsigned long last_local = 0;
4333 /* Write out the section symbols for the output sections. */
4334 if (info->shared)
4336 asection *s;
4338 sym.st_size = 0;
4339 sym.st_name = 0;
4340 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4341 sym.st_other = 0;
4343 for (s = abfd->sections; s != NULL; s = s->next)
4345 int indx;
4346 indx = elf_section_data (s)->this_idx;
4347 BFD_ASSERT (indx > 0);
4348 sym.st_shndx = indx;
4349 sym.st_value = s->vma;
4351 elf_swap_symbol_out (abfd, &sym,
4352 dynsym + elf_section_data (s)->dynindx);
4355 last_local = bfd_count_sections (abfd);
4358 /* Write out the local dynsyms. */
4359 if (elf_hash_table (info)->dynlocal)
4361 struct elf_link_local_dynamic_entry *e;
4362 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4364 asection *s;
4366 sym.st_size = e->isym.st_size;
4367 sym.st_other = e->isym.st_other;
4369 /* Copy the internal symbol as is.
4370 Note that we saved a word of storage and overwrote
4371 the original st_name with the dynstr_index. */
4372 sym = e->isym;
4374 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4376 s = bfd_section_from_elf_index (e->input_bfd,
4377 e->isym.st_shndx);
4379 sym.st_shndx =
4380 elf_section_data (s->output_section)->this_idx;
4381 sym.st_value = (s->output_section->vma
4382 + s->output_offset
4383 + e->isym.st_value);
4386 if (last_local < e->dynindx)
4387 last_local = e->dynindx;
4389 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4393 elf_section_data (finfo.dynsym_sec->output_section)
4394 ->this_hdr.sh_info = last_local + 1;
4397 /* We get the global symbols from the hash table. */
4398 eoinfo.failed = false;
4399 eoinfo.localsyms = false;
4400 eoinfo.finfo = &finfo;
4401 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4402 (PTR) &eoinfo);
4403 if (eoinfo.failed)
4404 return false;
4406 /* If backend needs to output some symbols not present in the hash
4407 table, do it now. */
4408 if (bed->elf_backend_output_arch_syms)
4410 if (! (*bed->elf_backend_output_arch_syms)
4411 (abfd, info, (PTR) &finfo,
4412 (boolean (*) PARAMS ((PTR, const char *,
4413 Elf_Internal_Sym *, asection *)))
4414 elf_link_output_sym))
4415 return false;
4418 /* Flush all symbols to the file. */
4419 if (! elf_link_flush_output_syms (&finfo))
4420 return false;
4422 /* Now we know the size of the symtab section. */
4423 off += symtab_hdr->sh_size;
4425 /* Finish up and write out the symbol string table (.strtab)
4426 section. */
4427 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4428 /* sh_name was set in prep_headers. */
4429 symstrtab_hdr->sh_type = SHT_STRTAB;
4430 symstrtab_hdr->sh_flags = 0;
4431 symstrtab_hdr->sh_addr = 0;
4432 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4433 symstrtab_hdr->sh_entsize = 0;
4434 symstrtab_hdr->sh_link = 0;
4435 symstrtab_hdr->sh_info = 0;
4436 /* sh_offset is set just below. */
4437 symstrtab_hdr->sh_addralign = 1;
4439 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4440 elf_tdata (abfd)->next_file_pos = off;
4442 if (bfd_get_symcount (abfd) > 0)
4444 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4445 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4446 return false;
4449 /* Adjust the relocs to have the correct symbol indices. */
4450 for (o = abfd->sections; o != NULL; o = o->next)
4452 if ((o->flags & SEC_RELOC) == 0)
4453 continue;
4455 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4456 elf_section_data (o)->rel_count,
4457 elf_section_data (o)->rel_hashes);
4458 if (elf_section_data (o)->rel_hdr2 != NULL)
4459 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4460 elf_section_data (o)->rel_count2,
4461 (elf_section_data (o)->rel_hashes
4462 + elf_section_data (o)->rel_count));
4464 /* Set the reloc_count field to 0 to prevent write_relocs from
4465 trying to swap the relocs out itself. */
4466 o->reloc_count = 0;
4469 /* If we are linking against a dynamic object, or generating a
4470 shared library, finish up the dynamic linking information. */
4471 if (dynamic)
4473 Elf_External_Dyn *dyncon, *dynconend;
4475 /* Fix up .dynamic entries. */
4476 o = bfd_get_section_by_name (dynobj, ".dynamic");
4477 BFD_ASSERT (o != NULL);
4479 dyncon = (Elf_External_Dyn *) o->contents;
4480 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4481 for (; dyncon < dynconend; dyncon++)
4483 Elf_Internal_Dyn dyn;
4484 const char *name;
4485 unsigned int type;
4487 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4489 switch (dyn.d_tag)
4491 default:
4492 break;
4493 case DT_INIT:
4494 name = info->init_function;
4495 goto get_sym;
4496 case DT_FINI:
4497 name = info->fini_function;
4498 get_sym:
4500 struct elf_link_hash_entry *h;
4502 h = elf_link_hash_lookup (elf_hash_table (info), name,
4503 false, false, true);
4504 if (h != NULL
4505 && (h->root.type == bfd_link_hash_defined
4506 || h->root.type == bfd_link_hash_defweak))
4508 dyn.d_un.d_val = h->root.u.def.value;
4509 o = h->root.u.def.section;
4510 if (o->output_section != NULL)
4511 dyn.d_un.d_val += (o->output_section->vma
4512 + o->output_offset);
4513 else
4515 /* The symbol is imported from another shared
4516 library and does not apply to this one. */
4517 dyn.d_un.d_val = 0;
4520 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4523 break;
4525 case DT_HASH:
4526 name = ".hash";
4527 goto get_vma;
4528 case DT_STRTAB:
4529 name = ".dynstr";
4530 goto get_vma;
4531 case DT_SYMTAB:
4532 name = ".dynsym";
4533 goto get_vma;
4534 case DT_VERDEF:
4535 name = ".gnu.version_d";
4536 goto get_vma;
4537 case DT_VERNEED:
4538 name = ".gnu.version_r";
4539 goto get_vma;
4540 case DT_VERSYM:
4541 name = ".gnu.version";
4542 get_vma:
4543 o = bfd_get_section_by_name (abfd, name);
4544 BFD_ASSERT (o != NULL);
4545 dyn.d_un.d_ptr = o->vma;
4546 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4547 break;
4549 case DT_REL:
4550 case DT_RELA:
4551 case DT_RELSZ:
4552 case DT_RELASZ:
4553 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4554 type = SHT_REL;
4555 else
4556 type = SHT_RELA;
4557 dyn.d_un.d_val = 0;
4558 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4560 Elf_Internal_Shdr *hdr;
4562 hdr = elf_elfsections (abfd)[i];
4563 if (hdr->sh_type == type
4564 && (hdr->sh_flags & SHF_ALLOC) != 0)
4566 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4567 dyn.d_un.d_val += hdr->sh_size;
4568 else
4570 if (dyn.d_un.d_val == 0
4571 || hdr->sh_addr < dyn.d_un.d_val)
4572 dyn.d_un.d_val = hdr->sh_addr;
4576 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4577 break;
4582 /* If we have created any dynamic sections, then output them. */
4583 if (dynobj != NULL)
4585 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4586 goto error_return;
4588 for (o = dynobj->sections; o != NULL; o = o->next)
4590 if ((o->flags & SEC_HAS_CONTENTS) == 0
4591 || o->_raw_size == 0)
4592 continue;
4593 if ((o->flags & SEC_LINKER_CREATED) == 0)
4595 /* At this point, we are only interested in sections
4596 created by elf_link_create_dynamic_sections. */
4597 continue;
4599 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4600 != SHT_STRTAB)
4601 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4603 if (! bfd_set_section_contents (abfd, o->output_section,
4604 o->contents, o->output_offset,
4605 o->_raw_size))
4606 goto error_return;
4608 else
4610 file_ptr off;
4612 /* The contents of the .dynstr section are actually in a
4613 stringtab. */
4614 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4615 if (bfd_seek (abfd, off, SEEK_SET) != 0
4616 || ! _bfd_stringtab_emit (abfd,
4617 elf_hash_table (info)->dynstr))
4618 goto error_return;
4623 /* If we have optimized stabs strings, output them. */
4624 if (elf_hash_table (info)->stab_info != NULL)
4626 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4627 goto error_return;
4630 if (finfo.symstrtab != NULL)
4631 _bfd_stringtab_free (finfo.symstrtab);
4632 if (finfo.contents != NULL)
4633 free (finfo.contents);
4634 if (finfo.external_relocs != NULL)
4635 free (finfo.external_relocs);
4636 if (finfo.internal_relocs != NULL)
4637 free (finfo.internal_relocs);
4638 if (finfo.external_syms != NULL)
4639 free (finfo.external_syms);
4640 if (finfo.internal_syms != NULL)
4641 free (finfo.internal_syms);
4642 if (finfo.indices != NULL)
4643 free (finfo.indices);
4644 if (finfo.sections != NULL)
4645 free (finfo.sections);
4646 if (finfo.symbuf != NULL)
4647 free (finfo.symbuf);
4648 for (o = abfd->sections; o != NULL; o = o->next)
4650 if ((o->flags & SEC_RELOC) != 0
4651 && elf_section_data (o)->rel_hashes != NULL)
4652 free (elf_section_data (o)->rel_hashes);
4655 elf_tdata (abfd)->linker = true;
4657 return true;
4659 error_return:
4660 if (finfo.symstrtab != NULL)
4661 _bfd_stringtab_free (finfo.symstrtab);
4662 if (finfo.contents != NULL)
4663 free (finfo.contents);
4664 if (finfo.external_relocs != NULL)
4665 free (finfo.external_relocs);
4666 if (finfo.internal_relocs != NULL)
4667 free (finfo.internal_relocs);
4668 if (finfo.external_syms != NULL)
4669 free (finfo.external_syms);
4670 if (finfo.internal_syms != NULL)
4671 free (finfo.internal_syms);
4672 if (finfo.indices != NULL)
4673 free (finfo.indices);
4674 if (finfo.sections != NULL)
4675 free (finfo.sections);
4676 if (finfo.symbuf != NULL)
4677 free (finfo.symbuf);
4678 for (o = abfd->sections; o != NULL; o = o->next)
4680 if ((o->flags & SEC_RELOC) != 0
4681 && elf_section_data (o)->rel_hashes != NULL)
4682 free (elf_section_data (o)->rel_hashes);
4685 return false;
4688 /* Add a symbol to the output symbol table. */
4690 static boolean
4691 elf_link_output_sym (finfo, name, elfsym, input_sec)
4692 struct elf_final_link_info *finfo;
4693 const char *name;
4694 Elf_Internal_Sym *elfsym;
4695 asection *input_sec;
4697 boolean (*output_symbol_hook) PARAMS ((bfd *,
4698 struct bfd_link_info *info,
4699 const char *,
4700 Elf_Internal_Sym *,
4701 asection *));
4703 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4704 elf_backend_link_output_symbol_hook;
4705 if (output_symbol_hook != NULL)
4707 if (! ((*output_symbol_hook)
4708 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4709 return false;
4712 if (name == (const char *) NULL || *name == '\0')
4713 elfsym->st_name = 0;
4714 else if (input_sec->flags & SEC_EXCLUDE)
4715 elfsym->st_name = 0;
4716 else
4718 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4719 name, true,
4720 false);
4721 if (elfsym->st_name == (unsigned long) -1)
4722 return false;
4725 if (finfo->symbuf_count >= finfo->symbuf_size)
4727 if (! elf_link_flush_output_syms (finfo))
4728 return false;
4731 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4732 (PTR) (finfo->symbuf + finfo->symbuf_count));
4733 ++finfo->symbuf_count;
4735 ++ bfd_get_symcount (finfo->output_bfd);
4737 return true;
4740 /* Flush the output symbols to the file. */
4742 static boolean
4743 elf_link_flush_output_syms (finfo)
4744 struct elf_final_link_info *finfo;
4746 if (finfo->symbuf_count > 0)
4748 Elf_Internal_Shdr *symtab;
4750 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4752 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4753 SEEK_SET) != 0
4754 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4755 sizeof (Elf_External_Sym), finfo->output_bfd)
4756 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4757 return false;
4759 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4761 finfo->symbuf_count = 0;
4764 return true;
4767 /* Add an external symbol to the symbol table. This is called from
4768 the hash table traversal routine. When generating a shared object,
4769 we go through the symbol table twice. The first time we output
4770 anything that might have been forced to local scope in a version
4771 script. The second time we output the symbols that are still
4772 global symbols. */
4774 static boolean
4775 elf_link_output_extsym (h, data)
4776 struct elf_link_hash_entry *h;
4777 PTR data;
4779 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4780 struct elf_final_link_info *finfo = eoinfo->finfo;
4781 boolean strip;
4782 Elf_Internal_Sym sym;
4783 asection *input_sec;
4785 /* Decide whether to output this symbol in this pass. */
4786 if (eoinfo->localsyms)
4788 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4789 return true;
4791 else
4793 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4794 return true;
4797 /* If we are not creating a shared library, and this symbol is
4798 referenced by a shared library but is not defined anywhere, then
4799 warn that it is undefined. If we do not do this, the runtime
4800 linker will complain that the symbol is undefined when the
4801 program is run. We don't have to worry about symbols that are
4802 referenced by regular files, because we will already have issued
4803 warnings for them. */
4804 if (! finfo->info->relocateable
4805 && ! (finfo->info->shared
4806 && !finfo->info->no_undefined)
4807 && h->root.type == bfd_link_hash_undefined
4808 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4809 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4811 if (! ((*finfo->info->callbacks->undefined_symbol)
4812 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4813 (asection *) NULL, 0)))
4815 eoinfo->failed = true;
4816 return false;
4820 /* We don't want to output symbols that have never been mentioned by
4821 a regular file, or that we have been told to strip. However, if
4822 h->indx is set to -2, the symbol is used by a reloc and we must
4823 output it. */
4824 if (h->indx == -2)
4825 strip = false;
4826 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4827 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4828 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4829 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4830 strip = true;
4831 else if (finfo->info->strip == strip_all
4832 || (finfo->info->strip == strip_some
4833 && bfd_hash_lookup (finfo->info->keep_hash,
4834 h->root.root.string,
4835 false, false) == NULL))
4836 strip = true;
4837 else
4838 strip = false;
4840 /* If we're stripping it, and it's not a dynamic symbol, there's
4841 nothing else to do. */
4842 if (strip && h->dynindx == -1)
4843 return true;
4845 sym.st_value = 0;
4846 sym.st_size = h->size;
4847 sym.st_other = h->other;
4848 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4849 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4850 else if (h->root.type == bfd_link_hash_undefweak
4851 || h->root.type == bfd_link_hash_defweak)
4852 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4853 else
4854 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4856 switch (h->root.type)
4858 default:
4859 case bfd_link_hash_new:
4860 abort ();
4861 return false;
4863 case bfd_link_hash_undefined:
4864 input_sec = bfd_und_section_ptr;
4865 sym.st_shndx = SHN_UNDEF;
4866 break;
4868 case bfd_link_hash_undefweak:
4869 input_sec = bfd_und_section_ptr;
4870 sym.st_shndx = SHN_UNDEF;
4871 break;
4873 case bfd_link_hash_defined:
4874 case bfd_link_hash_defweak:
4876 input_sec = h->root.u.def.section;
4877 if (input_sec->output_section != NULL)
4879 sym.st_shndx =
4880 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4881 input_sec->output_section);
4882 if (sym.st_shndx == (unsigned short) -1)
4884 (*_bfd_error_handler)
4885 (_("%s: could not find output section %s for input section %s"),
4886 bfd_get_filename (finfo->output_bfd),
4887 input_sec->output_section->name,
4888 input_sec->name);
4889 eoinfo->failed = true;
4890 return false;
4893 /* ELF symbols in relocateable files are section relative,
4894 but in nonrelocateable files they are virtual
4895 addresses. */
4896 sym.st_value = h->root.u.def.value + input_sec->output_offset;
4897 if (! finfo->info->relocateable)
4898 sym.st_value += input_sec->output_section->vma;
4900 else
4902 BFD_ASSERT (input_sec->owner == NULL
4903 || (input_sec->owner->flags & DYNAMIC) != 0);
4904 sym.st_shndx = SHN_UNDEF;
4905 input_sec = bfd_und_section_ptr;
4908 break;
4910 case bfd_link_hash_common:
4911 input_sec = h->root.u.c.p->section;
4912 sym.st_shndx = SHN_COMMON;
4913 sym.st_value = 1 << h->root.u.c.p->alignment_power;
4914 break;
4916 case bfd_link_hash_indirect:
4917 /* These symbols are created by symbol versioning. They point
4918 to the decorated version of the name. For example, if the
4919 symbol foo@@GNU_1.2 is the default, which should be used when
4920 foo is used with no version, then we add an indirect symbol
4921 foo which points to foo@@GNU_1.2. We ignore these symbols,
4922 since the indirected symbol is already in the hash table. If
4923 the indirect symbol is non-ELF, fall through and output it. */
4924 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
4925 return true;
4927 /* Fall through. */
4928 case bfd_link_hash_warning:
4929 /* We can't represent these symbols in ELF, although a warning
4930 symbol may have come from a .gnu.warning.SYMBOL section. We
4931 just put the target symbol in the hash table. If the target
4932 symbol does not really exist, don't do anything. */
4933 if (h->root.u.i.link->type == bfd_link_hash_new)
4934 return true;
4935 return (elf_link_output_extsym
4936 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
4939 /* Give the processor backend a chance to tweak the symbol value,
4940 and also to finish up anything that needs to be done for this
4941 symbol. */
4942 if ((h->dynindx != -1
4943 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4944 && elf_hash_table (finfo->info)->dynamic_sections_created)
4946 struct elf_backend_data *bed;
4948 bed = get_elf_backend_data (finfo->output_bfd);
4949 if (! ((*bed->elf_backend_finish_dynamic_symbol)
4950 (finfo->output_bfd, finfo->info, h, &sym)))
4952 eoinfo->failed = true;
4953 return false;
4957 /* If we are marking the symbol as undefined, and there are no
4958 non-weak references to this symbol from a regular object, then
4959 mark the symbol as weak undefined; if there are non-weak
4960 references, mark the symbol as strong. We can't do this earlier,
4961 because it might not be marked as undefined until the
4962 finish_dynamic_symbol routine gets through with it. */
4963 if (sym.st_shndx == SHN_UNDEF
4964 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
4965 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
4966 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
4968 int bindtype;
4970 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
4971 bindtype = STB_GLOBAL;
4972 else
4973 bindtype = STB_WEAK;
4974 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
4977 /* If this symbol should be put in the .dynsym section, then put it
4978 there now. We have already know the symbol index. We also fill
4979 in the entry in the .hash section. */
4980 if (h->dynindx != -1
4981 && elf_hash_table (finfo->info)->dynamic_sections_created)
4983 size_t bucketcount;
4984 size_t bucket;
4985 size_t hash_entry_size;
4986 bfd_byte *bucketpos;
4987 bfd_vma chain;
4989 sym.st_name = h->dynstr_index;
4991 elf_swap_symbol_out (finfo->output_bfd, &sym,
4992 (PTR) (((Elf_External_Sym *)
4993 finfo->dynsym_sec->contents)
4994 + h->dynindx));
4996 bucketcount = elf_hash_table (finfo->info)->bucketcount;
4997 bucket = h->elf_hash_value % bucketcount;
4998 hash_entry_size
4999 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5000 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5001 + (bucket + 2) * hash_entry_size);
5002 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5003 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5004 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5005 ((bfd_byte *) finfo->hash_sec->contents
5006 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5008 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5010 Elf_Internal_Versym iversym;
5012 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5014 if (h->verinfo.verdef == NULL)
5015 iversym.vs_vers = 0;
5016 else
5017 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5019 else
5021 if (h->verinfo.vertree == NULL)
5022 iversym.vs_vers = 1;
5023 else
5024 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5027 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5028 iversym.vs_vers |= VERSYM_HIDDEN;
5030 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5031 (((Elf_External_Versym *)
5032 finfo->symver_sec->contents)
5033 + h->dynindx));
5037 /* If we're stripping it, then it was just a dynamic symbol, and
5038 there's nothing else to do. */
5039 if (strip)
5040 return true;
5042 h->indx = bfd_get_symcount (finfo->output_bfd);
5044 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5046 eoinfo->failed = true;
5047 return false;
5050 return true;
5053 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5054 originated from the section given by INPUT_REL_HDR) to the
5055 OUTPUT_BFD. */
5057 static void
5058 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5059 internal_relocs)
5060 bfd *output_bfd;
5061 asection *input_section;
5062 Elf_Internal_Shdr *input_rel_hdr;
5063 Elf_Internal_Rela *internal_relocs;
5065 Elf_Internal_Rela *irela;
5066 Elf_Internal_Rela *irelaend;
5067 Elf_Internal_Shdr *output_rel_hdr;
5068 asection *output_section;
5069 unsigned int *rel_countp = NULL;
5071 output_section = input_section->output_section;
5072 output_rel_hdr = NULL;
5074 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5075 == input_rel_hdr->sh_entsize)
5077 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5078 rel_countp = &elf_section_data (output_section)->rel_count;
5080 else if (elf_section_data (output_section)->rel_hdr2
5081 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5082 == input_rel_hdr->sh_entsize))
5084 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5085 rel_countp = &elf_section_data (output_section)->rel_count2;
5088 BFD_ASSERT (output_rel_hdr != NULL);
5090 irela = internal_relocs;
5091 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5092 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5094 Elf_External_Rel *erel;
5096 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5097 for (; irela < irelaend; irela++, erel++)
5099 Elf_Internal_Rel irel;
5101 irel.r_offset = irela->r_offset;
5102 irel.r_info = irela->r_info;
5103 BFD_ASSERT (irela->r_addend == 0);
5104 elf_swap_reloc_out (output_bfd, &irel, erel);
5107 else
5109 Elf_External_Rela *erela;
5111 BFD_ASSERT (input_rel_hdr->sh_entsize
5112 == sizeof (Elf_External_Rela));
5113 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5114 for (; irela < irelaend; irela++, erela++)
5115 elf_swap_reloca_out (output_bfd, irela, erela);
5118 /* Bump the counter, so that we know where to add the next set of
5119 relocations. */
5120 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5123 /* Link an input file into the linker output file. This function
5124 handles all the sections and relocations of the input file at once.
5125 This is so that we only have to read the local symbols once, and
5126 don't have to keep them in memory. */
5128 static boolean
5129 elf_link_input_bfd (finfo, input_bfd)
5130 struct elf_final_link_info *finfo;
5131 bfd *input_bfd;
5133 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5134 bfd *, asection *, bfd_byte *,
5135 Elf_Internal_Rela *,
5136 Elf_Internal_Sym *, asection **));
5137 bfd *output_bfd;
5138 Elf_Internal_Shdr *symtab_hdr;
5139 size_t locsymcount;
5140 size_t extsymoff;
5141 Elf_External_Sym *external_syms;
5142 Elf_External_Sym *esym;
5143 Elf_External_Sym *esymend;
5144 Elf_Internal_Sym *isym;
5145 long *pindex;
5146 asection **ppsection;
5147 asection *o;
5148 struct elf_backend_data *bed;
5150 output_bfd = finfo->output_bfd;
5151 bed = get_elf_backend_data (output_bfd);
5152 relocate_section = bed->elf_backend_relocate_section;
5154 /* If this is a dynamic object, we don't want to do anything here:
5155 we don't want the local symbols, and we don't want the section
5156 contents. */
5157 if ((input_bfd->flags & DYNAMIC) != 0)
5158 return true;
5160 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5161 if (elf_bad_symtab (input_bfd))
5163 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5164 extsymoff = 0;
5166 else
5168 locsymcount = symtab_hdr->sh_info;
5169 extsymoff = symtab_hdr->sh_info;
5172 /* Read the local symbols. */
5173 if (symtab_hdr->contents != NULL)
5174 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5175 else if (locsymcount == 0)
5176 external_syms = NULL;
5177 else
5179 external_syms = finfo->external_syms;
5180 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5181 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5182 locsymcount, input_bfd)
5183 != locsymcount * sizeof (Elf_External_Sym)))
5184 return false;
5187 /* Swap in the local symbols and write out the ones which we know
5188 are going into the output file. */
5189 esym = external_syms;
5190 esymend = esym + locsymcount;
5191 isym = finfo->internal_syms;
5192 pindex = finfo->indices;
5193 ppsection = finfo->sections;
5194 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5196 asection *isec;
5197 const char *name;
5198 Elf_Internal_Sym osym;
5200 elf_swap_symbol_in (input_bfd, esym, isym);
5201 *pindex = -1;
5203 if (elf_bad_symtab (input_bfd))
5205 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5207 *ppsection = NULL;
5208 continue;
5212 if (isym->st_shndx == SHN_UNDEF)
5213 isec = bfd_und_section_ptr;
5214 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5215 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5216 else if (isym->st_shndx == SHN_ABS)
5217 isec = bfd_abs_section_ptr;
5218 else if (isym->st_shndx == SHN_COMMON)
5219 isec = bfd_com_section_ptr;
5220 else
5222 /* Who knows? */
5223 isec = NULL;
5226 *ppsection = isec;
5228 /* Don't output the first, undefined, symbol. */
5229 if (esym == external_syms)
5230 continue;
5232 /* If we are stripping all symbols, we don't want to output this
5233 one. */
5234 if (finfo->info->strip == strip_all)
5235 continue;
5237 /* We never output section symbols. Instead, we use the section
5238 symbol of the corresponding section in the output file. */
5239 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5240 continue;
5242 /* If we are discarding all local symbols, we don't want to
5243 output this one. If we are generating a relocateable output
5244 file, then some of the local symbols may be required by
5245 relocs; we output them below as we discover that they are
5246 needed. */
5247 if (finfo->info->discard == discard_all)
5248 continue;
5250 /* If this symbol is defined in a section which we are
5251 discarding, we don't need to keep it, but note that
5252 linker_mark is only reliable for sections that have contents.
5253 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5254 as well as linker_mark. */
5255 if (isym->st_shndx > 0
5256 && isym->st_shndx < SHN_LORESERVE
5257 && isec != NULL
5258 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5259 || (! finfo->info->relocateable
5260 && (isec->flags & SEC_EXCLUDE) != 0)))
5261 continue;
5263 /* Get the name of the symbol. */
5264 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5265 isym->st_name);
5266 if (name == NULL)
5267 return false;
5269 /* See if we are discarding symbols with this name. */
5270 if ((finfo->info->strip == strip_some
5271 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5272 == NULL))
5273 || (finfo->info->discard == discard_l
5274 && bfd_is_local_label_name (input_bfd, name)))
5275 continue;
5277 /* If we get here, we are going to output this symbol. */
5279 osym = *isym;
5281 /* Adjust the section index for the output file. */
5282 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5283 isec->output_section);
5284 if (osym.st_shndx == (unsigned short) -1)
5285 return false;
5287 *pindex = bfd_get_symcount (output_bfd);
5289 /* ELF symbols in relocateable files are section relative, but
5290 in executable files they are virtual addresses. Note that
5291 this code assumes that all ELF sections have an associated
5292 BFD section with a reasonable value for output_offset; below
5293 we assume that they also have a reasonable value for
5294 output_section. Any special sections must be set up to meet
5295 these requirements. */
5296 osym.st_value += isec->output_offset;
5297 if (! finfo->info->relocateable)
5298 osym.st_value += isec->output_section->vma;
5300 if (! elf_link_output_sym (finfo, name, &osym, isec))
5301 return false;
5304 /* Relocate the contents of each section. */
5305 for (o = input_bfd->sections; o != NULL; o = o->next)
5307 bfd_byte *contents;
5309 if (! o->linker_mark)
5311 /* This section was omitted from the link. */
5312 continue;
5315 if ((o->flags & SEC_HAS_CONTENTS) == 0
5316 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5317 continue;
5319 if ((o->flags & SEC_LINKER_CREATED) != 0)
5321 /* Section was created by elf_link_create_dynamic_sections
5322 or somesuch. */
5323 continue;
5326 /* Get the contents of the section. They have been cached by a
5327 relaxation routine. Note that o is a section in an input
5328 file, so the contents field will not have been set by any of
5329 the routines which work on output files. */
5330 if (elf_section_data (o)->this_hdr.contents != NULL)
5331 contents = elf_section_data (o)->this_hdr.contents;
5332 else
5334 contents = finfo->contents;
5335 if (! bfd_get_section_contents (input_bfd, o, contents,
5336 (file_ptr) 0, o->_raw_size))
5337 return false;
5340 if ((o->flags & SEC_RELOC) != 0)
5342 Elf_Internal_Rela *internal_relocs;
5344 /* Get the swapped relocs. */
5345 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5346 (input_bfd, o, finfo->external_relocs,
5347 finfo->internal_relocs, false));
5348 if (internal_relocs == NULL
5349 && o->reloc_count > 0)
5350 return false;
5352 /* Relocate the section by invoking a back end routine.
5354 The back end routine is responsible for adjusting the
5355 section contents as necessary, and (if using Rela relocs
5356 and generating a relocateable output file) adjusting the
5357 reloc addend as necessary.
5359 The back end routine does not have to worry about setting
5360 the reloc address or the reloc symbol index.
5362 The back end routine is given a pointer to the swapped in
5363 internal symbols, and can access the hash table entries
5364 for the external symbols via elf_sym_hashes (input_bfd).
5366 When generating relocateable output, the back end routine
5367 must handle STB_LOCAL/STT_SECTION symbols specially. The
5368 output symbol is going to be a section symbol
5369 corresponding to the output section, which will require
5370 the addend to be adjusted. */
5372 if (! (*relocate_section) (output_bfd, finfo->info,
5373 input_bfd, o, contents,
5374 internal_relocs,
5375 finfo->internal_syms,
5376 finfo->sections))
5377 return false;
5379 if (finfo->info->relocateable)
5381 Elf_Internal_Rela *irela;
5382 Elf_Internal_Rela *irelaend;
5383 struct elf_link_hash_entry **rel_hash;
5384 Elf_Internal_Shdr *input_rel_hdr;
5386 /* Adjust the reloc addresses and symbol indices. */
5388 irela = internal_relocs;
5389 irelaend =
5390 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5391 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5392 + elf_section_data (o->output_section)->rel_count
5393 + elf_section_data (o->output_section)->rel_count2);
5394 for (; irela < irelaend; irela++, rel_hash++)
5396 unsigned long r_symndx;
5397 Elf_Internal_Sym *isym;
5398 asection *sec;
5400 irela->r_offset += o->output_offset;
5402 r_symndx = ELF_R_SYM (irela->r_info);
5404 if (r_symndx == 0)
5405 continue;
5407 if (r_symndx >= locsymcount
5408 || (elf_bad_symtab (input_bfd)
5409 && finfo->sections[r_symndx] == NULL))
5411 struct elf_link_hash_entry *rh;
5412 long indx;
5414 /* This is a reloc against a global symbol. We
5415 have not yet output all the local symbols, so
5416 we do not know the symbol index of any global
5417 symbol. We set the rel_hash entry for this
5418 reloc to point to the global hash table entry
5419 for this symbol. The symbol index is then
5420 set at the end of elf_bfd_final_link. */
5421 indx = r_symndx - extsymoff;
5422 rh = elf_sym_hashes (input_bfd)[indx];
5423 while (rh->root.type == bfd_link_hash_indirect
5424 || rh->root.type == bfd_link_hash_warning)
5425 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5427 /* Setting the index to -2 tells
5428 elf_link_output_extsym that this symbol is
5429 used by a reloc. */
5430 BFD_ASSERT (rh->indx < 0);
5431 rh->indx = -2;
5433 *rel_hash = rh;
5435 continue;
5438 /* This is a reloc against a local symbol. */
5440 *rel_hash = NULL;
5441 isym = finfo->internal_syms + r_symndx;
5442 sec = finfo->sections[r_symndx];
5443 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5445 /* I suppose the backend ought to fill in the
5446 section of any STT_SECTION symbol against a
5447 processor specific section. If we have
5448 discarded a section, the output_section will
5449 be the absolute section. */
5450 if (sec != NULL
5451 && (bfd_is_abs_section (sec)
5452 || (sec->output_section != NULL
5453 && bfd_is_abs_section (sec->output_section))))
5454 r_symndx = 0;
5455 else if (sec == NULL || sec->owner == NULL)
5457 bfd_set_error (bfd_error_bad_value);
5458 return false;
5460 else
5462 r_symndx = sec->output_section->target_index;
5463 BFD_ASSERT (r_symndx != 0);
5466 else
5468 if (finfo->indices[r_symndx] == -1)
5470 unsigned long link;
5471 const char *name;
5472 asection *osec;
5474 if (finfo->info->strip == strip_all)
5476 /* You can't do ld -r -s. */
5477 bfd_set_error (bfd_error_invalid_operation);
5478 return false;
5481 /* This symbol was skipped earlier, but
5482 since it is needed by a reloc, we
5483 must output it now. */
5484 link = symtab_hdr->sh_link;
5485 name = bfd_elf_string_from_elf_section (input_bfd,
5486 link,
5487 isym->st_name);
5488 if (name == NULL)
5489 return false;
5491 osec = sec->output_section;
5492 isym->st_shndx =
5493 _bfd_elf_section_from_bfd_section (output_bfd,
5494 osec);
5495 if (isym->st_shndx == (unsigned short) -1)
5496 return false;
5498 isym->st_value += sec->output_offset;
5499 if (! finfo->info->relocateable)
5500 isym->st_value += osec->vma;
5502 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5504 if (! elf_link_output_sym (finfo, name, isym, sec))
5505 return false;
5508 r_symndx = finfo->indices[r_symndx];
5511 irela->r_info = ELF_R_INFO (r_symndx,
5512 ELF_R_TYPE (irela->r_info));
5515 /* Swap out the relocs. */
5516 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5517 elf_link_output_relocs (output_bfd, o,
5518 input_rel_hdr,
5519 internal_relocs);
5520 internal_relocs
5521 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5522 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5523 if (input_rel_hdr)
5524 elf_link_output_relocs (output_bfd, o,
5525 input_rel_hdr,
5526 internal_relocs);
5530 /* Write out the modified section contents. */
5531 if (elf_section_data (o)->stab_info == NULL)
5533 if (! (o->flags & SEC_EXCLUDE) &&
5534 ! bfd_set_section_contents (output_bfd, o->output_section,
5535 contents, o->output_offset,
5536 (o->_cooked_size != 0
5537 ? o->_cooked_size
5538 : o->_raw_size)))
5539 return false;
5541 else
5543 if (! (_bfd_write_section_stabs
5544 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5545 o, &elf_section_data (o)->stab_info, contents)))
5546 return false;
5550 return true;
5553 /* Generate a reloc when linking an ELF file. This is a reloc
5554 requested by the linker, and does come from any input file. This
5555 is used to build constructor and destructor tables when linking
5556 with -Ur. */
5558 static boolean
5559 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5560 bfd *output_bfd;
5561 struct bfd_link_info *info;
5562 asection *output_section;
5563 struct bfd_link_order *link_order;
5565 reloc_howto_type *howto;
5566 long indx;
5567 bfd_vma offset;
5568 bfd_vma addend;
5569 struct elf_link_hash_entry **rel_hash_ptr;
5570 Elf_Internal_Shdr *rel_hdr;
5572 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5573 if (howto == NULL)
5575 bfd_set_error (bfd_error_bad_value);
5576 return false;
5579 addend = link_order->u.reloc.p->addend;
5581 /* Figure out the symbol index. */
5582 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5583 + elf_section_data (output_section)->rel_count
5584 + elf_section_data (output_section)->rel_count2);
5585 if (link_order->type == bfd_section_reloc_link_order)
5587 indx = link_order->u.reloc.p->u.section->target_index;
5588 BFD_ASSERT (indx != 0);
5589 *rel_hash_ptr = NULL;
5591 else
5593 struct elf_link_hash_entry *h;
5595 /* Treat a reloc against a defined symbol as though it were
5596 actually against the section. */
5597 h = ((struct elf_link_hash_entry *)
5598 bfd_wrapped_link_hash_lookup (output_bfd, info,
5599 link_order->u.reloc.p->u.name,
5600 false, false, true));
5601 if (h != NULL
5602 && (h->root.type == bfd_link_hash_defined
5603 || h->root.type == bfd_link_hash_defweak))
5605 asection *section;
5607 section = h->root.u.def.section;
5608 indx = section->output_section->target_index;
5609 *rel_hash_ptr = NULL;
5610 /* It seems that we ought to add the symbol value to the
5611 addend here, but in practice it has already been added
5612 because it was passed to constructor_callback. */
5613 addend += section->output_section->vma + section->output_offset;
5615 else if (h != NULL)
5617 /* Setting the index to -2 tells elf_link_output_extsym that
5618 this symbol is used by a reloc. */
5619 h->indx = -2;
5620 *rel_hash_ptr = h;
5621 indx = 0;
5623 else
5625 if (! ((*info->callbacks->unattached_reloc)
5626 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5627 (asection *) NULL, (bfd_vma) 0)))
5628 return false;
5629 indx = 0;
5633 /* If this is an inplace reloc, we must write the addend into the
5634 object file. */
5635 if (howto->partial_inplace && addend != 0)
5637 bfd_size_type size;
5638 bfd_reloc_status_type rstat;
5639 bfd_byte *buf;
5640 boolean ok;
5642 size = bfd_get_reloc_size (howto);
5643 buf = (bfd_byte *) bfd_zmalloc (size);
5644 if (buf == (bfd_byte *) NULL)
5645 return false;
5646 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5647 switch (rstat)
5649 case bfd_reloc_ok:
5650 break;
5651 default:
5652 case bfd_reloc_outofrange:
5653 abort ();
5654 case bfd_reloc_overflow:
5655 if (! ((*info->callbacks->reloc_overflow)
5656 (info,
5657 (link_order->type == bfd_section_reloc_link_order
5658 ? bfd_section_name (output_bfd,
5659 link_order->u.reloc.p->u.section)
5660 : link_order->u.reloc.p->u.name),
5661 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5662 (bfd_vma) 0)))
5664 free (buf);
5665 return false;
5667 break;
5669 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5670 (file_ptr) link_order->offset, size);
5671 free (buf);
5672 if (! ok)
5673 return false;
5676 /* The address of a reloc is relative to the section in a
5677 relocateable file, and is a virtual address in an executable
5678 file. */
5679 offset = link_order->offset;
5680 if (! info->relocateable)
5681 offset += output_section->vma;
5683 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5685 if (rel_hdr->sh_type == SHT_REL)
5687 Elf_Internal_Rel irel;
5688 Elf_External_Rel *erel;
5690 irel.r_offset = offset;
5691 irel.r_info = ELF_R_INFO (indx, howto->type);
5692 erel = ((Elf_External_Rel *) rel_hdr->contents
5693 + elf_section_data (output_section)->rel_count);
5694 elf_swap_reloc_out (output_bfd, &irel, erel);
5696 else
5698 Elf_Internal_Rela irela;
5699 Elf_External_Rela *erela;
5701 irela.r_offset = offset;
5702 irela.r_info = ELF_R_INFO (indx, howto->type);
5703 irela.r_addend = addend;
5704 erela = ((Elf_External_Rela *) rel_hdr->contents
5705 + elf_section_data (output_section)->rel_count);
5706 elf_swap_reloca_out (output_bfd, &irela, erela);
5709 ++elf_section_data (output_section)->rel_count;
5711 return true;
5715 /* Allocate a pointer to live in a linker created section. */
5717 boolean
5718 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5719 bfd *abfd;
5720 struct bfd_link_info *info;
5721 elf_linker_section_t *lsect;
5722 struct elf_link_hash_entry *h;
5723 const Elf_Internal_Rela *rel;
5725 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5726 elf_linker_section_pointers_t *linker_section_ptr;
5727 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5729 BFD_ASSERT (lsect != NULL);
5731 /* Is this a global symbol? */
5732 if (h != NULL)
5734 /* Has this symbol already been allocated, if so, our work is done */
5735 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5736 rel->r_addend,
5737 lsect->which))
5738 return true;
5740 ptr_linker_section_ptr = &h->linker_section_pointer;
5741 /* Make sure this symbol is output as a dynamic symbol. */
5742 if (h->dynindx == -1)
5744 if (! elf_link_record_dynamic_symbol (info, h))
5745 return false;
5748 if (lsect->rel_section)
5749 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5752 else /* Allocation of a pointer to a local symbol */
5754 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5756 /* Allocate a table to hold the local symbols if first time */
5757 if (!ptr)
5759 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5760 register unsigned int i;
5762 ptr = (elf_linker_section_pointers_t **)
5763 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5765 if (!ptr)
5766 return false;
5768 elf_local_ptr_offsets (abfd) = ptr;
5769 for (i = 0; i < num_symbols; i++)
5770 ptr[i] = (elf_linker_section_pointers_t *)0;
5773 /* Has this symbol already been allocated, if so, our work is done */
5774 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5775 rel->r_addend,
5776 lsect->which))
5777 return true;
5779 ptr_linker_section_ptr = &ptr[r_symndx];
5781 if (info->shared)
5783 /* If we are generating a shared object, we need to
5784 output a R_<xxx>_RELATIVE reloc so that the
5785 dynamic linker can adjust this GOT entry. */
5786 BFD_ASSERT (lsect->rel_section != NULL);
5787 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5791 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5792 from internal memory. */
5793 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5794 linker_section_ptr = (elf_linker_section_pointers_t *)
5795 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5797 if (!linker_section_ptr)
5798 return false;
5800 linker_section_ptr->next = *ptr_linker_section_ptr;
5801 linker_section_ptr->addend = rel->r_addend;
5802 linker_section_ptr->which = lsect->which;
5803 linker_section_ptr->written_address_p = false;
5804 *ptr_linker_section_ptr = linker_section_ptr;
5806 #if 0
5807 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5809 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5810 lsect->hole_offset += ARCH_SIZE / 8;
5811 lsect->sym_offset += ARCH_SIZE / 8;
5812 if (lsect->sym_hash) /* Bump up symbol value if needed */
5814 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5815 #ifdef DEBUG
5816 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5817 lsect->sym_hash->root.root.string,
5818 (long)ARCH_SIZE / 8,
5819 (long)lsect->sym_hash->root.u.def.value);
5820 #endif
5823 else
5824 #endif
5825 linker_section_ptr->offset = lsect->section->_raw_size;
5827 lsect->section->_raw_size += ARCH_SIZE / 8;
5829 #ifdef DEBUG
5830 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5831 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5832 #endif
5834 return true;
5838 #if ARCH_SIZE==64
5839 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5840 #endif
5841 #if ARCH_SIZE==32
5842 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5843 #endif
5845 /* Fill in the address for a pointer generated in alinker section. */
5847 bfd_vma
5848 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5849 bfd *output_bfd;
5850 bfd *input_bfd;
5851 struct bfd_link_info *info;
5852 elf_linker_section_t *lsect;
5853 struct elf_link_hash_entry *h;
5854 bfd_vma relocation;
5855 const Elf_Internal_Rela *rel;
5856 int relative_reloc;
5858 elf_linker_section_pointers_t *linker_section_ptr;
5860 BFD_ASSERT (lsect != NULL);
5862 if (h != NULL) /* global symbol */
5864 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5865 rel->r_addend,
5866 lsect->which);
5868 BFD_ASSERT (linker_section_ptr != NULL);
5870 if (! elf_hash_table (info)->dynamic_sections_created
5871 || (info->shared
5872 && info->symbolic
5873 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5875 /* This is actually a static link, or it is a
5876 -Bsymbolic link and the symbol is defined
5877 locally. We must initialize this entry in the
5878 global section.
5880 When doing a dynamic link, we create a .rela.<xxx>
5881 relocation entry to initialize the value. This
5882 is done in the finish_dynamic_symbol routine. */
5883 if (!linker_section_ptr->written_address_p)
5885 linker_section_ptr->written_address_p = true;
5886 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5887 lsect->section->contents + linker_section_ptr->offset);
5891 else /* local symbol */
5893 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
5894 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
5895 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
5896 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
5897 rel->r_addend,
5898 lsect->which);
5900 BFD_ASSERT (linker_section_ptr != NULL);
5902 /* Write out pointer if it hasn't been rewritten out before */
5903 if (!linker_section_ptr->written_address_p)
5905 linker_section_ptr->written_address_p = true;
5906 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5907 lsect->section->contents + linker_section_ptr->offset);
5909 if (info->shared)
5911 asection *srel = lsect->rel_section;
5912 Elf_Internal_Rela outrel;
5914 /* We need to generate a relative reloc for the dynamic linker. */
5915 if (!srel)
5916 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
5917 lsect->rel_name);
5919 BFD_ASSERT (srel != NULL);
5921 outrel.r_offset = (lsect->section->output_section->vma
5922 + lsect->section->output_offset
5923 + linker_section_ptr->offset);
5924 outrel.r_info = ELF_R_INFO (0, relative_reloc);
5925 outrel.r_addend = 0;
5926 elf_swap_reloca_out (output_bfd, &outrel,
5927 (((Elf_External_Rela *)
5928 lsect->section->contents)
5929 + elf_section_data (lsect->section)->rel_count));
5930 ++elf_section_data (lsect->section)->rel_count;
5935 relocation = (lsect->section->output_offset
5936 + linker_section_ptr->offset
5937 - lsect->hole_offset
5938 - lsect->sym_offset);
5940 #ifdef DEBUG
5941 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
5942 lsect->name, (long)relocation, (long)relocation);
5943 #endif
5945 /* Subtract out the addend, because it will get added back in by the normal
5946 processing. */
5947 return relocation - linker_section_ptr->addend;
5950 /* Garbage collect unused sections. */
5952 static boolean elf_gc_mark
5953 PARAMS ((struct bfd_link_info *info, asection *sec,
5954 asection * (*gc_mark_hook)
5955 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
5956 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
5958 static boolean elf_gc_sweep
5959 PARAMS ((struct bfd_link_info *info,
5960 boolean (*gc_sweep_hook)
5961 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
5962 const Elf_Internal_Rela *relocs))));
5964 static boolean elf_gc_sweep_symbol
5965 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
5967 static boolean elf_gc_allocate_got_offsets
5968 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
5970 static boolean elf_gc_propagate_vtable_entries_used
5971 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
5973 static boolean elf_gc_smash_unused_vtentry_relocs
5974 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
5976 /* The mark phase of garbage collection. For a given section, mark
5977 it, and all the sections which define symbols to which it refers. */
5979 static boolean
5980 elf_gc_mark (info, sec, gc_mark_hook)
5981 struct bfd_link_info *info;
5982 asection *sec;
5983 asection * (*gc_mark_hook)
5984 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
5985 struct elf_link_hash_entry *, Elf_Internal_Sym *));
5987 boolean ret = true;
5989 sec->gc_mark = 1;
5991 /* Look through the section relocs. */
5993 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
5995 Elf_Internal_Rela *relstart, *rel, *relend;
5996 Elf_Internal_Shdr *symtab_hdr;
5997 struct elf_link_hash_entry **sym_hashes;
5998 size_t nlocsyms;
5999 size_t extsymoff;
6000 Elf_External_Sym *locsyms, *freesyms = NULL;
6001 bfd *input_bfd = sec->owner;
6002 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6004 /* GCFIXME: how to arrange so that relocs and symbols are not
6005 reread continually? */
6007 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6008 sym_hashes = elf_sym_hashes (input_bfd);
6010 /* Read the local symbols. */
6011 if (elf_bad_symtab (input_bfd))
6013 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6014 extsymoff = 0;
6016 else
6017 extsymoff = nlocsyms = symtab_hdr->sh_info;
6018 if (symtab_hdr->contents)
6019 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6020 else if (nlocsyms == 0)
6021 locsyms = NULL;
6022 else
6024 locsyms = freesyms =
6025 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6026 if (freesyms == NULL
6027 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6028 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6029 nlocsyms, input_bfd)
6030 != nlocsyms * sizeof (Elf_External_Sym)))
6032 ret = false;
6033 goto out1;
6037 /* Read the relocations. */
6038 relstart = (NAME(_bfd_elf,link_read_relocs)
6039 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6040 info->keep_memory));
6041 if (relstart == NULL)
6043 ret = false;
6044 goto out1;
6046 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6048 for (rel = relstart; rel < relend; rel++)
6050 unsigned long r_symndx;
6051 asection *rsec;
6052 struct elf_link_hash_entry *h;
6053 Elf_Internal_Sym s;
6055 r_symndx = ELF_R_SYM (rel->r_info);
6056 if (r_symndx == 0)
6057 continue;
6059 if (elf_bad_symtab (sec->owner))
6061 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6062 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6063 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6064 else
6066 h = sym_hashes[r_symndx - extsymoff];
6067 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6070 else if (r_symndx >= nlocsyms)
6072 h = sym_hashes[r_symndx - extsymoff];
6073 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6075 else
6077 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6078 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6081 if (rsec && !rsec->gc_mark)
6082 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6084 ret = false;
6085 goto out2;
6089 out2:
6090 if (!info->keep_memory)
6091 free (relstart);
6092 out1:
6093 if (freesyms)
6094 free (freesyms);
6097 return ret;
6100 /* The sweep phase of garbage collection. Remove all garbage sections. */
6102 static boolean
6103 elf_gc_sweep (info, gc_sweep_hook)
6104 struct bfd_link_info *info;
6105 boolean (*gc_sweep_hook)
6106 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6107 const Elf_Internal_Rela *relocs));
6109 bfd *sub;
6111 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6113 asection *o;
6115 for (o = sub->sections; o != NULL; o = o->next)
6117 /* Keep special sections. Keep .debug sections. */
6118 if ((o->flags & SEC_LINKER_CREATED)
6119 || (o->flags & SEC_DEBUGGING))
6120 o->gc_mark = 1;
6122 if (o->gc_mark)
6123 continue;
6125 /* Skip sweeping sections already excluded. */
6126 if (o->flags & SEC_EXCLUDE)
6127 continue;
6129 /* Since this is early in the link process, it is simple
6130 to remove a section from the output. */
6131 o->flags |= SEC_EXCLUDE;
6133 /* But we also have to update some of the relocation
6134 info we collected before. */
6135 if (gc_sweep_hook
6136 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6138 Elf_Internal_Rela *internal_relocs;
6139 boolean r;
6141 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6142 (o->owner, o, NULL, NULL, info->keep_memory));
6143 if (internal_relocs == NULL)
6144 return false;
6146 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6148 if (!info->keep_memory)
6149 free (internal_relocs);
6151 if (!r)
6152 return false;
6157 /* Remove the symbols that were in the swept sections from the dynamic
6158 symbol table. GCFIXME: Anyone know how to get them out of the
6159 static symbol table as well? */
6161 int i = 0;
6163 elf_link_hash_traverse (elf_hash_table (info),
6164 elf_gc_sweep_symbol,
6165 (PTR) &i);
6167 elf_hash_table (info)->dynsymcount = i;
6170 return true;
6173 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6175 static boolean
6176 elf_gc_sweep_symbol (h, idxptr)
6177 struct elf_link_hash_entry *h;
6178 PTR idxptr;
6180 int *idx = (int *) idxptr;
6182 if (h->dynindx != -1
6183 && ((h->root.type != bfd_link_hash_defined
6184 && h->root.type != bfd_link_hash_defweak)
6185 || h->root.u.def.section->gc_mark))
6186 h->dynindx = (*idx)++;
6188 return true;
6191 /* Propogate collected vtable information. This is called through
6192 elf_link_hash_traverse. */
6194 static boolean
6195 elf_gc_propagate_vtable_entries_used (h, okp)
6196 struct elf_link_hash_entry *h;
6197 PTR okp;
6199 /* Those that are not vtables. */
6200 if (h->vtable_parent == NULL)
6201 return true;
6203 /* Those vtables that do not have parents, we cannot merge. */
6204 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6205 return true;
6207 /* If we've already been done, exit. */
6208 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6209 return true;
6211 /* Make sure the parent's table is up to date. */
6212 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6214 if (h->vtable_entries_used == NULL)
6216 /* None of this table's entries were referenced. Re-use the
6217 parent's table. */
6218 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6219 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6221 else
6223 size_t n;
6224 boolean *cu, *pu;
6226 /* Or the parent's entries into ours. */
6227 cu = h->vtable_entries_used;
6228 cu[-1] = true;
6229 pu = h->vtable_parent->vtable_entries_used;
6230 if (pu != NULL)
6232 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6233 while (--n != 0)
6235 if (*pu) *cu = true;
6236 pu++, cu++;
6241 return true;
6244 static boolean
6245 elf_gc_smash_unused_vtentry_relocs (h, okp)
6246 struct elf_link_hash_entry *h;
6247 PTR okp;
6249 asection *sec;
6250 bfd_vma hstart, hend;
6251 Elf_Internal_Rela *relstart, *relend, *rel;
6252 struct elf_backend_data *bed;
6254 /* Take care of both those symbols that do not describe vtables as
6255 well as those that are not loaded. */
6256 if (h->vtable_parent == NULL)
6257 return true;
6259 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6260 || h->root.type == bfd_link_hash_defweak);
6262 sec = h->root.u.def.section;
6263 hstart = h->root.u.def.value;
6264 hend = hstart + h->size;
6266 relstart = (NAME(_bfd_elf,link_read_relocs)
6267 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6268 if (!relstart)
6269 return *(boolean *)okp = false;
6270 bed = get_elf_backend_data (sec->owner);
6271 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6273 for (rel = relstart; rel < relend; ++rel)
6274 if (rel->r_offset >= hstart && rel->r_offset < hend)
6276 /* If the entry is in use, do nothing. */
6277 if (h->vtable_entries_used
6278 && (rel->r_offset - hstart) < h->vtable_entries_size)
6280 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6281 if (h->vtable_entries_used[entry])
6282 continue;
6284 /* Otherwise, kill it. */
6285 rel->r_offset = rel->r_info = rel->r_addend = 0;
6288 return true;
6291 /* Do mark and sweep of unused sections. */
6293 boolean
6294 elf_gc_sections (abfd, info)
6295 bfd *abfd;
6296 struct bfd_link_info *info;
6298 boolean ok = true;
6299 bfd *sub;
6300 asection * (*gc_mark_hook)
6301 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6302 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6304 if (!get_elf_backend_data (abfd)->can_gc_sections
6305 || info->relocateable
6306 || elf_hash_table (info)->dynamic_sections_created)
6307 return true;
6309 /* Apply transitive closure to the vtable entry usage info. */
6310 elf_link_hash_traverse (elf_hash_table (info),
6311 elf_gc_propagate_vtable_entries_used,
6312 (PTR) &ok);
6313 if (!ok)
6314 return false;
6316 /* Kill the vtable relocations that were not used. */
6317 elf_link_hash_traverse (elf_hash_table (info),
6318 elf_gc_smash_unused_vtentry_relocs,
6319 (PTR) &ok);
6320 if (!ok)
6321 return false;
6323 /* Grovel through relocs to find out who stays ... */
6325 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6326 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6328 asection *o;
6329 for (o = sub->sections; o != NULL; o = o->next)
6331 if (o->flags & SEC_KEEP)
6332 if (!elf_gc_mark (info, o, gc_mark_hook))
6333 return false;
6337 /* ... and mark SEC_EXCLUDE for those that go. */
6338 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6339 return false;
6341 return true;
6344 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6346 boolean
6347 elf_gc_record_vtinherit (abfd, sec, h, offset)
6348 bfd *abfd;
6349 asection *sec;
6350 struct elf_link_hash_entry *h;
6351 bfd_vma offset;
6353 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6354 struct elf_link_hash_entry **search, *child;
6355 bfd_size_type extsymcount;
6357 /* The sh_info field of the symtab header tells us where the
6358 external symbols start. We don't care about the local symbols at
6359 this point. */
6360 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6361 if (!elf_bad_symtab (abfd))
6362 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6364 sym_hashes = elf_sym_hashes (abfd);
6365 sym_hashes_end = sym_hashes + extsymcount;
6367 /* Hunt down the child symbol, which is in this section at the same
6368 offset as the relocation. */
6369 for (search = sym_hashes; search != sym_hashes_end; ++search)
6371 if ((child = *search) != NULL
6372 && (child->root.type == bfd_link_hash_defined
6373 || child->root.type == bfd_link_hash_defweak)
6374 && child->root.u.def.section == sec
6375 && child->root.u.def.value == offset)
6376 goto win;
6379 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6380 bfd_get_filename (abfd), sec->name,
6381 (unsigned long)offset);
6382 bfd_set_error (bfd_error_invalid_operation);
6383 return false;
6385 win:
6386 if (!h)
6388 /* This *should* only be the absolute section. It could potentially
6389 be that someone has defined a non-global vtable though, which
6390 would be bad. It isn't worth paging in the local symbols to be
6391 sure though; that case should simply be handled by the assembler. */
6393 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6395 else
6396 child->vtable_parent = h;
6398 return true;
6401 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6403 boolean
6404 elf_gc_record_vtentry (abfd, sec, h, addend)
6405 bfd *abfd ATTRIBUTE_UNUSED;
6406 asection *sec ATTRIBUTE_UNUSED;
6407 struct elf_link_hash_entry *h;
6408 bfd_vma addend;
6410 if (addend >= h->vtable_entries_size)
6412 size_t size, bytes;
6413 boolean *ptr = h->vtable_entries_used;
6415 /* While the symbol is undefined, we have to be prepared to handle
6416 a zero size. */
6417 if (h->root.type == bfd_link_hash_undefined)
6418 size = addend;
6419 else
6421 size = h->size;
6422 if (size < addend)
6424 /* Oops! We've got a reference past the defined end of
6425 the table. This is probably a bug -- shall we warn? */
6426 size = addend;
6430 /* Allocate one extra entry for use as a "done" flag for the
6431 consolidation pass. */
6432 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6434 if (ptr)
6436 ptr = bfd_realloc (ptr - 1, bytes);
6438 if (ptr != NULL)
6440 size_t oldbytes;
6442 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6443 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6446 else
6447 ptr = bfd_zmalloc (bytes);
6449 if (ptr == NULL)
6450 return false;
6452 /* And arrange for that done flag to be at index -1. */
6453 h->vtable_entries_used = ptr + 1;
6454 h->vtable_entries_size = size;
6457 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6459 return true;
6462 /* And an accompanying bit to work out final got entry offsets once
6463 we're done. Should be called from final_link. */
6465 boolean
6466 elf_gc_common_finalize_got_offsets (abfd, info)
6467 bfd *abfd;
6468 struct bfd_link_info *info;
6470 bfd *i;
6471 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6472 bfd_vma gotoff;
6474 /* The GOT offset is relative to the .got section, but the GOT header is
6475 put into the .got.plt section, if the backend uses it. */
6476 if (bed->want_got_plt)
6477 gotoff = 0;
6478 else
6479 gotoff = bed->got_header_size;
6481 /* Do the local .got entries first. */
6482 for (i = info->input_bfds; i; i = i->link_next)
6484 bfd_signed_vma *local_got = elf_local_got_refcounts (i);
6485 bfd_size_type j, locsymcount;
6486 Elf_Internal_Shdr *symtab_hdr;
6488 if (!local_got)
6489 continue;
6491 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6492 if (elf_bad_symtab (i))
6493 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6494 else
6495 locsymcount = symtab_hdr->sh_info;
6497 for (j = 0; j < locsymcount; ++j)
6499 if (local_got[j] > 0)
6501 local_got[j] = gotoff;
6502 gotoff += ARCH_SIZE / 8;
6504 else
6505 local_got[j] = (bfd_vma) -1;
6509 /* Then the global .got and .plt entries. */
6510 elf_link_hash_traverse (elf_hash_table (info),
6511 elf_gc_allocate_got_offsets,
6512 (PTR) &gotoff);
6513 return true;
6516 /* We need a special top-level link routine to convert got reference counts
6517 to real got offsets. */
6519 static boolean
6520 elf_gc_allocate_got_offsets (h, offarg)
6521 struct elf_link_hash_entry *h;
6522 PTR offarg;
6524 bfd_vma *off = (bfd_vma *) offarg;
6526 if (h->got.refcount > 0)
6528 h->got.offset = off[0];
6529 off[0] += ARCH_SIZE / 8;
6531 else
6532 h->got.offset = (bfd_vma) -1;
6534 return true;
6537 /* Many folk need no more in the way of final link than this, once
6538 got entry reference counting is enabled. */
6540 boolean
6541 elf_gc_common_final_link (abfd, info)
6542 bfd *abfd;
6543 struct bfd_link_info *info;
6545 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6546 return false;
6548 /* Invoke the regular ELF backend linker to do all the work. */
6549 return elf_bfd_final_link (abfd, info);
6552 /* This function will be called though elf_link_hash_traverse to store
6553 all hash value of the exported symbols in an array. */
6555 static boolean
6556 elf_collect_hash_codes (h, data)
6557 struct elf_link_hash_entry *h;
6558 PTR data;
6560 unsigned long **valuep = (unsigned long **) data;
6561 const char *name;
6562 char *p;
6563 unsigned long ha;
6564 char *alc = NULL;
6566 /* Ignore indirect symbols. These are added by the versioning code. */
6567 if (h->dynindx == -1)
6568 return true;
6570 name = h->root.root.string;
6571 p = strchr (name, ELF_VER_CHR);
6572 if (p != NULL)
6574 alc = bfd_malloc (p - name + 1);
6575 memcpy (alc, name, p - name);
6576 alc[p - name] = '\0';
6577 name = alc;
6580 /* Compute the hash value. */
6581 ha = bfd_elf_hash (name);
6583 /* Store the found hash value in the array given as the argument. */
6584 *(*valuep)++ = ha;
6586 /* And store it in the struct so that we can put it in the hash table
6587 later. */
6588 h->elf_hash_value = ha;
6590 if (alc != NULL)
6591 free (alc);
6593 return true;