2000-06-05 H.J. Lu <hjl@gnu.org>
[binutils.git] / bfd / elflink.h
bloba1390d30b2dfba222f2cade1613dea5bc756c23f
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000 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;
83 /* Return true iff this is a non-common definition of a symbol. */
84 static boolean
85 is_global_symbol_definition (abfd, sym)
86 bfd * abfd ATTRIBUTE_UNUSED;
87 Elf_Internal_Sym * sym;
89 /* Local symbols do not count, but target specific ones might. */
90 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
91 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
92 return false;
94 /* If the section is undefined, then so is the symbol. */
95 if (sym->st_shndx == SHN_UNDEF)
96 return false;
98 /* If the symbol is defined in the common section, then
99 it is a common definition and so does not count. */
100 if (sym->st_shndx == SHN_COMMON)
101 return false;
103 /* If the symbol is in a target specific section then we
104 must rely upon the backend to tell us what it is. */
105 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
106 /* FIXME - this function is not coded yet:
108 return _bfd_is_global_symbol_definition (abfd, sym);
110 Instead for now assume that the definition is not global,
111 Even if this is wrong, at least the linker will behave
112 in the same way that it used to do. */
113 return false;
115 return true;
119 /* Search the symbol table of the archive element of the archive ABFD
120 whoes archove map contains a mention of SYMDEF, and determine if
121 the symbol is defined in this element. */
122 static boolean
123 elf_link_is_defined_archive_symbol (abfd, symdef)
124 bfd * abfd;
125 carsym * symdef;
127 Elf_Internal_Shdr * hdr;
128 Elf_External_Sym * esym;
129 Elf_External_Sym * esymend;
130 Elf_External_Sym * buf = NULL;
131 size_t symcount;
132 size_t extsymcount;
133 size_t extsymoff;
134 boolean result = false;
136 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
137 if (abfd == (bfd *) NULL)
138 return false;
140 if (! bfd_check_format (abfd, bfd_object))
141 return false;
143 /* If we have already included the element containing this symbol in the
144 link then we do not need to include it again. Just claim that any symbol
145 it contains is not a definition, so that our caller will not decide to
146 (re)include this element. */
147 if (abfd->archive_pass)
148 return false;
150 /* Select the appropriate symbol table. */
151 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
152 hdr = &elf_tdata (abfd)->symtab_hdr;
153 else
154 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
156 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
158 /* The sh_info field of the symtab header tells us where the
159 external symbols start. We don't care about the local symbols. */
160 if (elf_bad_symtab (abfd))
162 extsymcount = symcount;
163 extsymoff = 0;
165 else
167 extsymcount = symcount - hdr->sh_info;
168 extsymoff = hdr->sh_info;
171 buf = ((Elf_External_Sym *)
172 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
173 if (buf == NULL && extsymcount != 0)
174 return false;
176 /* Read in the symbol table.
177 FIXME: This ought to be cached somewhere. */
178 if (bfd_seek (abfd,
179 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
180 SEEK_SET) != 0
181 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
182 != extsymcount * sizeof (Elf_External_Sym)))
184 free (buf);
185 return false;
188 /* Scan the symbol table looking for SYMDEF. */
189 esymend = buf + extsymcount;
190 for (esym = buf;
191 esym < esymend;
192 esym++)
194 Elf_Internal_Sym sym;
195 const char * name;
197 elf_swap_symbol_in (abfd, esym, & sym);
199 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
200 if (name == (const char *) NULL)
201 break;
203 if (strcmp (name, symdef->name) == 0)
205 result = is_global_symbol_definition (abfd, & sym);
206 break;
210 free (buf);
212 return result;
216 /* Add symbols from an ELF archive file to the linker hash table. We
217 don't use _bfd_generic_link_add_archive_symbols because of a
218 problem which arises on UnixWare. The UnixWare libc.so is an
219 archive which includes an entry libc.so.1 which defines a bunch of
220 symbols. The libc.so archive also includes a number of other
221 object files, which also define symbols, some of which are the same
222 as those defined in libc.so.1. Correct linking requires that we
223 consider each object file in turn, and include it if it defines any
224 symbols we need. _bfd_generic_link_add_archive_symbols does not do
225 this; it looks through the list of undefined symbols, and includes
226 any object file which defines them. When this algorithm is used on
227 UnixWare, it winds up pulling in libc.so.1 early and defining a
228 bunch of symbols. This means that some of the other objects in the
229 archive are not included in the link, which is incorrect since they
230 precede libc.so.1 in the archive.
232 Fortunately, ELF archive handling is simpler than that done by
233 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
234 oddities. In ELF, if we find a symbol in the archive map, and the
235 symbol is currently undefined, we know that we must pull in that
236 object file.
238 Unfortunately, we do have to make multiple passes over the symbol
239 table until nothing further is resolved. */
241 static boolean
242 elf_link_add_archive_symbols (abfd, info)
243 bfd *abfd;
244 struct bfd_link_info *info;
246 symindex c;
247 boolean *defined = NULL;
248 boolean *included = NULL;
249 carsym *symdefs;
250 boolean loop;
252 if (! bfd_has_map (abfd))
254 /* An empty archive is a special case. */
255 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
256 return true;
257 bfd_set_error (bfd_error_no_armap);
258 return false;
261 /* Keep track of all symbols we know to be already defined, and all
262 files we know to be already included. This is to speed up the
263 second and subsequent passes. */
264 c = bfd_ardata (abfd)->symdef_count;
265 if (c == 0)
266 return true;
267 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
268 included = (boolean *) bfd_malloc (c * sizeof (boolean));
269 if (defined == (boolean *) NULL || included == (boolean *) NULL)
270 goto error_return;
271 memset (defined, 0, c * sizeof (boolean));
272 memset (included, 0, c * sizeof (boolean));
274 symdefs = bfd_ardata (abfd)->symdefs;
278 file_ptr last;
279 symindex i;
280 carsym *symdef;
281 carsym *symdefend;
283 loop = false;
284 last = -1;
286 symdef = symdefs;
287 symdefend = symdef + c;
288 for (i = 0; symdef < symdefend; symdef++, i++)
290 struct elf_link_hash_entry *h;
291 bfd *element;
292 struct bfd_link_hash_entry *undefs_tail;
293 symindex mark;
295 if (defined[i] || included[i])
296 continue;
297 if (symdef->file_offset == last)
299 included[i] = true;
300 continue;
303 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
304 false, false, false);
306 if (h == NULL)
308 char *p, *copy;
310 /* If this is a default version (the name contains @@),
311 look up the symbol again without the version. The
312 effect is that references to the symbol without the
313 version will be matched by the default symbol in the
314 archive. */
316 p = strchr (symdef->name, ELF_VER_CHR);
317 if (p == NULL || p[1] != ELF_VER_CHR)
318 continue;
320 copy = bfd_alloc (abfd, p - symdef->name + 1);
321 if (copy == NULL)
322 goto error_return;
323 memcpy (copy, symdef->name, p - symdef->name);
324 copy[p - symdef->name] = '\0';
326 h = elf_link_hash_lookup (elf_hash_table (info), copy,
327 false, false, false);
329 bfd_release (abfd, copy);
332 if (h == NULL)
333 continue;
335 if (h->root.type == bfd_link_hash_common)
337 /* We currently have a common symbol. The archive map contains
338 a reference to this symbol, so we may want to include it. We
339 only want to include it however, if this archive element
340 contains a definition of the symbol, not just another common
341 declaration of it.
343 Unfortunately some archivers (including GNU ar) will put
344 declarations of common symbols into their archive maps, as
345 well as real definitions, so we cannot just go by the archive
346 map alone. Instead we must read in the element's symbol
347 table and check that to see what kind of symbol definition
348 this is. */
349 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
350 continue;
352 else if (h->root.type != bfd_link_hash_undefined)
354 if (h->root.type != bfd_link_hash_undefweak)
355 defined[i] = true;
356 continue;
359 /* We need to include this archive member. */
360 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
361 if (element == (bfd *) NULL)
362 goto error_return;
364 if (! bfd_check_format (element, bfd_object))
365 goto error_return;
367 /* Doublecheck that we have not included this object
368 already--it should be impossible, but there may be
369 something wrong with the archive. */
370 if (element->archive_pass != 0)
372 bfd_set_error (bfd_error_bad_value);
373 goto error_return;
375 element->archive_pass = 1;
377 undefs_tail = info->hash->undefs_tail;
379 if (! (*info->callbacks->add_archive_element) (info, element,
380 symdef->name))
381 goto error_return;
382 if (! elf_link_add_object_symbols (element, info))
383 goto error_return;
385 /* If there are any new undefined symbols, we need to make
386 another pass through the archive in order to see whether
387 they can be defined. FIXME: This isn't perfect, because
388 common symbols wind up on undefs_tail and because an
389 undefined symbol which is defined later on in this pass
390 does not require another pass. This isn't a bug, but it
391 does make the code less efficient than it could be. */
392 if (undefs_tail != info->hash->undefs_tail)
393 loop = true;
395 /* Look backward to mark all symbols from this object file
396 which we have already seen in this pass. */
397 mark = i;
400 included[mark] = true;
401 if (mark == 0)
402 break;
403 --mark;
405 while (symdefs[mark].file_offset == symdef->file_offset);
407 /* We mark subsequent symbols from this object file as we go
408 on through the loop. */
409 last = symdef->file_offset;
412 while (loop);
414 free (defined);
415 free (included);
417 return true;
419 error_return:
420 if (defined != (boolean *) NULL)
421 free (defined);
422 if (included != (boolean *) NULL)
423 free (included);
424 return false;
427 /* This function is called when we want to define a new symbol. It
428 handles the various cases which arise when we find a definition in
429 a dynamic object, or when there is already a definition in a
430 dynamic object. The new symbol is described by NAME, SYM, PSEC,
431 and PVALUE. We set SYM_HASH to the hash table entry. We set
432 OVERRIDE if the old symbol is overriding a new definition. We set
433 TYPE_CHANGE_OK if it is OK for the type to change. We set
434 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
435 change, we mean that we shouldn't warn if the type or size does
436 change. */
438 static boolean
439 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
440 override, type_change_ok, size_change_ok)
441 bfd *abfd;
442 struct bfd_link_info *info;
443 const char *name;
444 Elf_Internal_Sym *sym;
445 asection **psec;
446 bfd_vma *pvalue;
447 struct elf_link_hash_entry **sym_hash;
448 boolean *override;
449 boolean *type_change_ok;
450 boolean *size_change_ok;
452 asection *sec;
453 struct elf_link_hash_entry *h;
454 int bind;
455 bfd *oldbfd;
456 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
458 *override = false;
460 sec = *psec;
461 bind = ELF_ST_BIND (sym->st_info);
463 if (! bfd_is_und_section (sec))
464 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
465 else
466 h = ((struct elf_link_hash_entry *)
467 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
468 if (h == NULL)
469 return false;
470 *sym_hash = h;
472 /* This code is for coping with dynamic objects, and is only useful
473 if we are doing an ELF link. */
474 if (info->hash->creator != abfd->xvec)
475 return true;
477 /* For merging, we only care about real symbols. */
479 while (h->root.type == bfd_link_hash_indirect
480 || h->root.type == bfd_link_hash_warning)
481 h = (struct elf_link_hash_entry *) h->root.u.i.link;
483 /* If we just created the symbol, mark it as being an ELF symbol.
484 Other than that, there is nothing to do--there is no merge issue
485 with a newly defined symbol--so we just return. */
487 if (h->root.type == bfd_link_hash_new)
489 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
490 return true;
493 /* OLDBFD is a BFD associated with the existing symbol. */
495 switch (h->root.type)
497 default:
498 oldbfd = NULL;
499 break;
501 case bfd_link_hash_undefined:
502 case bfd_link_hash_undefweak:
503 oldbfd = h->root.u.undef.abfd;
504 break;
506 case bfd_link_hash_defined:
507 case bfd_link_hash_defweak:
508 oldbfd = h->root.u.def.section->owner;
509 break;
511 case bfd_link_hash_common:
512 oldbfd = h->root.u.c.p->section->owner;
513 break;
516 /* In cases involving weak versioned symbols, we may wind up trying
517 to merge a symbol with itself. Catch that here, to avoid the
518 confusion that results if we try to override a symbol with
519 itself. The additional tests catch cases like
520 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
521 dynamic object, which we do want to handle here. */
522 if (abfd == oldbfd
523 && ((abfd->flags & DYNAMIC) == 0
524 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
525 return true;
527 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
528 respectively, is from a dynamic object. */
530 if ((abfd->flags & DYNAMIC) != 0)
531 newdyn = true;
532 else
533 newdyn = false;
535 if (oldbfd != NULL)
536 olddyn = (oldbfd->flags & DYNAMIC) != 0;
537 else
539 asection *hsec;
541 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
542 indices used by MIPS ELF. */
543 switch (h->root.type)
545 default:
546 hsec = NULL;
547 break;
549 case bfd_link_hash_defined:
550 case bfd_link_hash_defweak:
551 hsec = h->root.u.def.section;
552 break;
554 case bfd_link_hash_common:
555 hsec = h->root.u.c.p->section;
556 break;
559 if (hsec == NULL)
560 olddyn = false;
561 else
562 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
565 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
566 respectively, appear to be a definition rather than reference. */
568 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
569 newdef = false;
570 else
571 newdef = true;
573 if (h->root.type == bfd_link_hash_undefined
574 || h->root.type == bfd_link_hash_undefweak
575 || h->root.type == bfd_link_hash_common)
576 olddef = false;
577 else
578 olddef = true;
580 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
581 symbol, respectively, appears to be a common symbol in a dynamic
582 object. If a symbol appears in an uninitialized section, and is
583 not weak, and is not a function, then it may be a common symbol
584 which was resolved when the dynamic object was created. We want
585 to treat such symbols specially, because they raise special
586 considerations when setting the symbol size: if the symbol
587 appears as a common symbol in a regular object, and the size in
588 the regular object is larger, we must make sure that we use the
589 larger size. This problematic case can always be avoided in C,
590 but it must be handled correctly when using Fortran shared
591 libraries.
593 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
594 likewise for OLDDYNCOMMON and OLDDEF.
596 Note that this test is just a heuristic, and that it is quite
597 possible to have an uninitialized symbol in a shared object which
598 is really a definition, rather than a common symbol. This could
599 lead to some minor confusion when the symbol really is a common
600 symbol in some regular object. However, I think it will be
601 harmless. */
603 if (newdyn
604 && newdef
605 && (sec->flags & SEC_ALLOC) != 0
606 && (sec->flags & SEC_LOAD) == 0
607 && sym->st_size > 0
608 && bind != STB_WEAK
609 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
610 newdyncommon = true;
611 else
612 newdyncommon = false;
614 if (olddyn
615 && olddef
616 && h->root.type == bfd_link_hash_defined
617 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
618 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
619 && (h->root.u.def.section->flags & SEC_LOAD) == 0
620 && h->size > 0
621 && h->type != STT_FUNC)
622 olddyncommon = true;
623 else
624 olddyncommon = false;
626 /* It's OK to change the type if either the existing symbol or the
627 new symbol is weak. */
629 if (h->root.type == bfd_link_hash_defweak
630 || h->root.type == bfd_link_hash_undefweak
631 || bind == STB_WEAK)
632 *type_change_ok = true;
634 /* It's OK to change the size if either the existing symbol or the
635 new symbol is weak, or if the old symbol is undefined. */
637 if (*type_change_ok
638 || h->root.type == bfd_link_hash_undefined)
639 *size_change_ok = true;
641 /* If both the old and the new symbols look like common symbols in a
642 dynamic object, set the size of the symbol to the larger of the
643 two. */
645 if (olddyncommon
646 && newdyncommon
647 && sym->st_size != h->size)
649 /* Since we think we have two common symbols, issue a multiple
650 common warning if desired. Note that we only warn if the
651 size is different. If the size is the same, we simply let
652 the old symbol override the new one as normally happens with
653 symbols defined in dynamic objects. */
655 if (! ((*info->callbacks->multiple_common)
656 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
657 h->size, abfd, bfd_link_hash_common, sym->st_size)))
658 return false;
660 if (sym->st_size > h->size)
661 h->size = sym->st_size;
663 *size_change_ok = true;
666 /* If we are looking at a dynamic object, and we have found a
667 definition, we need to see if the symbol was already defined by
668 some other object. If so, we want to use the existing
669 definition, and we do not want to report a multiple symbol
670 definition error; we do this by clobbering *PSEC to be
671 bfd_und_section_ptr.
673 We treat a common symbol as a definition if the symbol in the
674 shared library is a function, since common symbols always
675 represent variables; this can cause confusion in principle, but
676 any such confusion would seem to indicate an erroneous program or
677 shared library. We also permit a common symbol in a regular
678 object to override a weak symbol in a shared object.
680 We prefer a non-weak definition in a shared library to a weak
681 definition in the executable. */
683 if (newdyn
684 && newdef
685 && (olddef
686 || (h->root.type == bfd_link_hash_common
687 && (bind == STB_WEAK
688 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
689 && (h->root.type != bfd_link_hash_defweak
690 || bind == STB_WEAK))
692 *override = true;
693 newdef = false;
694 newdyncommon = false;
696 *psec = sec = bfd_und_section_ptr;
697 *size_change_ok = true;
699 /* If we get here when the old symbol is a common symbol, then
700 we are explicitly letting it override a weak symbol or
701 function in a dynamic object, and we don't want to warn about
702 a type change. If the old symbol is a defined symbol, a type
703 change warning may still be appropriate. */
705 if (h->root.type == bfd_link_hash_common)
706 *type_change_ok = true;
709 /* Handle the special case of an old common symbol merging with a
710 new symbol which looks like a common symbol in a shared object.
711 We change *PSEC and *PVALUE to make the new symbol look like a
712 common symbol, and let _bfd_generic_link_add_one_symbol will do
713 the right thing. */
715 if (newdyncommon
716 && h->root.type == bfd_link_hash_common)
718 *override = true;
719 newdef = false;
720 newdyncommon = false;
721 *pvalue = sym->st_size;
722 *psec = sec = bfd_com_section_ptr;
723 *size_change_ok = true;
726 /* If the old symbol is from a dynamic object, and the new symbol is
727 a definition which is not from a dynamic object, then the new
728 symbol overrides the old symbol. Symbols from regular files
729 always take precedence over symbols from dynamic objects, even if
730 they are defined after the dynamic object in the link.
732 As above, we again permit a common symbol in a regular object to
733 override a definition in a shared object if the shared object
734 symbol is a function or is weak.
736 As above, we permit a non-weak definition in a shared object to
737 override a weak definition in a regular object. */
739 if (! newdyn
740 && (newdef
741 || (bfd_is_com_section (sec)
742 && (h->root.type == bfd_link_hash_defweak
743 || h->type == STT_FUNC)))
744 && olddyn
745 && olddef
746 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
747 && (bind != STB_WEAK
748 || h->root.type == bfd_link_hash_defweak))
750 /* Change the hash table entry to undefined, and let
751 _bfd_generic_link_add_one_symbol do the right thing with the
752 new definition. */
754 h->root.type = bfd_link_hash_undefined;
755 h->root.u.undef.abfd = h->root.u.def.section->owner;
756 *size_change_ok = true;
758 olddef = false;
759 olddyncommon = false;
761 /* We again permit a type change when a common symbol may be
762 overriding a function. */
764 if (bfd_is_com_section (sec))
765 *type_change_ok = true;
767 /* This union may have been set to be non-NULL when this symbol
768 was seen in a dynamic object. We must force the union to be
769 NULL, so that it is correct for a regular symbol. */
771 h->verinfo.vertree = NULL;
773 /* In this special case, if H is the target of an indirection,
774 we want the caller to frob with H rather than with the
775 indirect symbol. That will permit the caller to redefine the
776 target of the indirection, rather than the indirect symbol
777 itself. FIXME: This will break the -y option if we store a
778 symbol with a different name. */
779 *sym_hash = h;
782 /* Handle the special case of a new common symbol merging with an
783 old symbol that looks like it might be a common symbol defined in
784 a shared object. Note that we have already handled the case in
785 which a new common symbol should simply override the definition
786 in the shared library. */
788 if (! newdyn
789 && bfd_is_com_section (sec)
790 && olddyncommon)
792 /* It would be best if we could set the hash table entry to a
793 common symbol, but we don't know what to use for the section
794 or the alignment. */
795 if (! ((*info->callbacks->multiple_common)
796 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
797 h->size, abfd, bfd_link_hash_common, sym->st_size)))
798 return false;
800 /* If the predumed common symbol in the dynamic object is
801 larger, pretend that the new symbol has its size. */
803 if (h->size > *pvalue)
804 *pvalue = h->size;
806 /* FIXME: We no longer know the alignment required by the symbol
807 in the dynamic object, so we just wind up using the one from
808 the regular object. */
810 olddef = false;
811 olddyncommon = false;
813 h->root.type = bfd_link_hash_undefined;
814 h->root.u.undef.abfd = h->root.u.def.section->owner;
816 *size_change_ok = true;
817 *type_change_ok = true;
819 h->verinfo.vertree = NULL;
822 /* Handle the special case of a weak definition in a regular object
823 followed by a non-weak definition in a shared object. In this
824 case, we prefer the definition in the shared object. */
825 if (olddef
826 && h->root.type == bfd_link_hash_defweak
827 && newdef
828 && newdyn
829 && bind != STB_WEAK)
831 /* To make this work we have to frob the flags so that the rest
832 of the code does not think we are using the regular
833 definition. */
834 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
835 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
836 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
837 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
838 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
839 | ELF_LINK_HASH_DEF_DYNAMIC);
841 /* If H is the target of an indirection, we want the caller to
842 use H rather than the indirect symbol. Otherwise if we are
843 defining a new indirect symbol we will wind up attaching it
844 to the entry we are overriding. */
845 *sym_hash = h;
848 /* Handle the special case of a non-weak definition in a shared
849 object followed by a weak definition in a regular object. In
850 this case we prefer to definition in the shared object. To make
851 this work we have to tell the caller to not treat the new symbol
852 as a definition. */
853 if (olddef
854 && olddyn
855 && h->root.type != bfd_link_hash_defweak
856 && newdef
857 && ! newdyn
858 && bind == STB_WEAK)
859 *override = true;
861 return true;
864 /* Add symbols from an ELF object file to the linker hash table. */
866 static boolean
867 elf_link_add_object_symbols (abfd, info)
868 bfd *abfd;
869 struct bfd_link_info *info;
871 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
872 const Elf_Internal_Sym *,
873 const char **, flagword *,
874 asection **, bfd_vma *));
875 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
876 asection *, const Elf_Internal_Rela *));
877 boolean collect;
878 Elf_Internal_Shdr *hdr;
879 size_t symcount;
880 size_t extsymcount;
881 size_t extsymoff;
882 Elf_External_Sym *buf = NULL;
883 struct elf_link_hash_entry **sym_hash;
884 boolean dynamic;
885 bfd_byte *dynver = NULL;
886 Elf_External_Versym *extversym = NULL;
887 Elf_External_Versym *ever;
888 Elf_External_Dyn *dynbuf = NULL;
889 struct elf_link_hash_entry *weaks;
890 Elf_External_Sym *esym;
891 Elf_External_Sym *esymend;
892 struct elf_backend_data *bed;
894 bed = get_elf_backend_data (abfd);
895 add_symbol_hook = bed->elf_add_symbol_hook;
896 collect = bed->collect;
898 if ((abfd->flags & DYNAMIC) == 0)
899 dynamic = false;
900 else
902 dynamic = true;
904 /* You can't use -r against a dynamic object. Also, there's no
905 hope of using a dynamic object which does not exactly match
906 the format of the output file. */
907 if (info->relocateable || info->hash->creator != abfd->xvec)
909 bfd_set_error (bfd_error_invalid_operation);
910 goto error_return;
914 /* As a GNU extension, any input sections which are named
915 .gnu.warning.SYMBOL are treated as warning symbols for the given
916 symbol. This differs from .gnu.warning sections, which generate
917 warnings when they are included in an output file. */
918 if (! info->shared)
920 asection *s;
922 for (s = abfd->sections; s != NULL; s = s->next)
924 const char *name;
926 name = bfd_get_section_name (abfd, s);
927 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
929 char *msg;
930 bfd_size_type sz;
932 name += sizeof ".gnu.warning." - 1;
934 /* If this is a shared object, then look up the symbol
935 in the hash table. If it is there, and it is already
936 been defined, then we will not be using the entry
937 from this shared object, so we don't need to warn.
938 FIXME: If we see the definition in a regular object
939 later on, we will warn, but we shouldn't. The only
940 fix is to keep track of what warnings we are supposed
941 to emit, and then handle them all at the end of the
942 link. */
943 if (dynamic && abfd->xvec == info->hash->creator)
945 struct elf_link_hash_entry *h;
947 h = elf_link_hash_lookup (elf_hash_table (info), name,
948 false, false, true);
950 /* FIXME: What about bfd_link_hash_common? */
951 if (h != NULL
952 && (h->root.type == bfd_link_hash_defined
953 || h->root.type == bfd_link_hash_defweak))
955 /* We don't want to issue this warning. Clobber
956 the section size so that the warning does not
957 get copied into the output file. */
958 s->_raw_size = 0;
959 continue;
963 sz = bfd_section_size (abfd, s);
964 msg = (char *) bfd_alloc (abfd, sz + 1);
965 if (msg == NULL)
966 goto error_return;
968 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
969 goto error_return;
971 msg[sz] = '\0';
973 if (! (_bfd_generic_link_add_one_symbol
974 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
975 false, collect, (struct bfd_link_hash_entry **) NULL)))
976 goto error_return;
978 if (! info->relocateable)
980 /* Clobber the section size so that the warning does
981 not get copied into the output file. */
982 s->_raw_size = 0;
988 /* If this is a dynamic object, we always link against the .dynsym
989 symbol table, not the .symtab symbol table. The dynamic linker
990 will only see the .dynsym symbol table, so there is no reason to
991 look at .symtab for a dynamic object. */
993 if (! dynamic || elf_dynsymtab (abfd) == 0)
994 hdr = &elf_tdata (abfd)->symtab_hdr;
995 else
996 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
998 if (dynamic)
1000 /* Read in any version definitions. */
1002 if (! _bfd_elf_slurp_version_tables (abfd))
1003 goto error_return;
1005 /* Read in the symbol versions, but don't bother to convert them
1006 to internal format. */
1007 if (elf_dynversym (abfd) != 0)
1009 Elf_Internal_Shdr *versymhdr;
1011 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1012 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1013 if (extversym == NULL)
1014 goto error_return;
1015 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1016 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1017 != versymhdr->sh_size))
1018 goto error_return;
1022 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1024 /* The sh_info field of the symtab header tells us where the
1025 external symbols start. We don't care about the local symbols at
1026 this point. */
1027 if (elf_bad_symtab (abfd))
1029 extsymcount = symcount;
1030 extsymoff = 0;
1032 else
1034 extsymcount = symcount - hdr->sh_info;
1035 extsymoff = hdr->sh_info;
1038 buf = ((Elf_External_Sym *)
1039 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1040 if (buf == NULL && extsymcount != 0)
1041 goto error_return;
1043 /* We store a pointer to the hash table entry for each external
1044 symbol. */
1045 sym_hash = ((struct elf_link_hash_entry **)
1046 bfd_alloc (abfd,
1047 extsymcount * sizeof (struct elf_link_hash_entry *)));
1048 if (sym_hash == NULL)
1049 goto error_return;
1050 elf_sym_hashes (abfd) = sym_hash;
1052 if (! dynamic)
1054 /* If we are creating a shared library, create all the dynamic
1055 sections immediately. We need to attach them to something,
1056 so we attach them to this BFD, provided it is the right
1057 format. FIXME: If there are no input BFD's of the same
1058 format as the output, we can't make a shared library. */
1059 if (info->shared
1060 && ! elf_hash_table (info)->dynamic_sections_created
1061 && abfd->xvec == info->hash->creator)
1063 if (! elf_link_create_dynamic_sections (abfd, info))
1064 goto error_return;
1067 else
1069 asection *s;
1070 boolean add_needed;
1071 const char *name;
1072 bfd_size_type oldsize;
1073 bfd_size_type strindex;
1075 /* Find the name to use in a DT_NEEDED entry that refers to this
1076 object. If the object has a DT_SONAME entry, we use it.
1077 Otherwise, if the generic linker stuck something in
1078 elf_dt_name, we use that. Otherwise, we just use the file
1079 name. If the generic linker put a null string into
1080 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1081 there is a DT_SONAME entry. */
1082 add_needed = true;
1083 name = bfd_get_filename (abfd);
1084 if (elf_dt_name (abfd) != NULL)
1086 name = elf_dt_name (abfd);
1087 if (*name == '\0')
1088 add_needed = false;
1090 s = bfd_get_section_by_name (abfd, ".dynamic");
1091 if (s != NULL)
1093 Elf_External_Dyn *extdyn;
1094 Elf_External_Dyn *extdynend;
1095 int elfsec;
1096 unsigned long link;
1098 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1099 if (dynbuf == NULL)
1100 goto error_return;
1102 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1103 (file_ptr) 0, s->_raw_size))
1104 goto error_return;
1106 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1107 if (elfsec == -1)
1108 goto error_return;
1109 link = elf_elfsections (abfd)[elfsec]->sh_link;
1112 /* The shared libraries distributed with hpux11 have a bogus
1113 sh_link field for the ".dynamic" section. This code detects
1114 when LINK refers to a section that is not a string table and
1115 tries to find the string table for the ".dynsym" section
1116 instead. */
1117 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1118 if (hdr->sh_type != SHT_STRTAB)
1120 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1121 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1122 if (elfsec == -1)
1123 goto error_return;
1124 link = elf_elfsections (abfd)[elfsec]->sh_link;
1128 extdyn = dynbuf;
1129 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1130 for (; extdyn < extdynend; extdyn++)
1132 Elf_Internal_Dyn dyn;
1134 elf_swap_dyn_in (abfd, extdyn, &dyn);
1135 if (dyn.d_tag == DT_SONAME)
1137 name = bfd_elf_string_from_elf_section (abfd, link,
1138 dyn.d_un.d_val);
1139 if (name == NULL)
1140 goto error_return;
1142 if (dyn.d_tag == DT_NEEDED)
1144 struct bfd_link_needed_list *n, **pn;
1145 char *fnm, *anm;
1147 n = ((struct bfd_link_needed_list *)
1148 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1149 fnm = bfd_elf_string_from_elf_section (abfd, link,
1150 dyn.d_un.d_val);
1151 if (n == NULL || fnm == NULL)
1152 goto error_return;
1153 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1154 if (anm == NULL)
1155 goto error_return;
1156 strcpy (anm, fnm);
1157 n->name = anm;
1158 n->by = abfd;
1159 n->next = NULL;
1160 for (pn = &elf_hash_table (info)->needed;
1161 *pn != NULL;
1162 pn = &(*pn)->next)
1164 *pn = n;
1168 free (dynbuf);
1169 dynbuf = NULL;
1172 /* We do not want to include any of the sections in a dynamic
1173 object in the output file. We hack by simply clobbering the
1174 list of sections in the BFD. This could be handled more
1175 cleanly by, say, a new section flag; the existing
1176 SEC_NEVER_LOAD flag is not the one we want, because that one
1177 still implies that the section takes up space in the output
1178 file. */
1179 abfd->sections = NULL;
1180 abfd->section_count = 0;
1182 /* If this is the first dynamic object found in the link, create
1183 the special sections required for dynamic linking. */
1184 if (! elf_hash_table (info)->dynamic_sections_created)
1186 if (! elf_link_create_dynamic_sections (abfd, info))
1187 goto error_return;
1190 if (add_needed)
1192 /* Add a DT_NEEDED entry for this dynamic object. */
1193 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1194 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1195 true, false);
1196 if (strindex == (bfd_size_type) -1)
1197 goto error_return;
1199 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1201 asection *sdyn;
1202 Elf_External_Dyn *dyncon, *dynconend;
1204 /* The hash table size did not change, which means that
1205 the dynamic object name was already entered. If we
1206 have already included this dynamic object in the
1207 link, just ignore it. There is no reason to include
1208 a particular dynamic object more than once. */
1209 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1210 ".dynamic");
1211 BFD_ASSERT (sdyn != NULL);
1213 dyncon = (Elf_External_Dyn *) sdyn->contents;
1214 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1215 sdyn->_raw_size);
1216 for (; dyncon < dynconend; dyncon++)
1218 Elf_Internal_Dyn dyn;
1220 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1221 &dyn);
1222 if (dyn.d_tag == DT_NEEDED
1223 && dyn.d_un.d_val == strindex)
1225 if (buf != NULL)
1226 free (buf);
1227 if (extversym != NULL)
1228 free (extversym);
1229 return true;
1234 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1235 goto error_return;
1238 /* Save the SONAME, if there is one, because sometimes the
1239 linker emulation code will need to know it. */
1240 if (*name == '\0')
1241 name = bfd_get_filename (abfd);
1242 elf_dt_name (abfd) = name;
1245 if (bfd_seek (abfd,
1246 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1247 SEEK_SET) != 0
1248 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1249 != extsymcount * sizeof (Elf_External_Sym)))
1250 goto error_return;
1252 weaks = NULL;
1254 ever = extversym != NULL ? extversym + extsymoff : NULL;
1255 esymend = buf + extsymcount;
1256 for (esym = buf;
1257 esym < esymend;
1258 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1260 Elf_Internal_Sym sym;
1261 int bind;
1262 bfd_vma value;
1263 asection *sec;
1264 flagword flags;
1265 const char *name;
1266 struct elf_link_hash_entry *h;
1267 boolean definition;
1268 boolean size_change_ok, type_change_ok;
1269 boolean new_weakdef;
1270 unsigned int old_alignment;
1272 elf_swap_symbol_in (abfd, esym, &sym);
1274 flags = BSF_NO_FLAGS;
1275 sec = NULL;
1276 value = sym.st_value;
1277 *sym_hash = NULL;
1279 bind = ELF_ST_BIND (sym.st_info);
1280 if (bind == STB_LOCAL)
1282 /* This should be impossible, since ELF requires that all
1283 global symbols follow all local symbols, and that sh_info
1284 point to the first global symbol. Unfortunatealy, Irix 5
1285 screws this up. */
1286 continue;
1288 else if (bind == STB_GLOBAL)
1290 if (sym.st_shndx != SHN_UNDEF
1291 && sym.st_shndx != SHN_COMMON)
1292 flags = BSF_GLOBAL;
1293 else
1294 flags = 0;
1296 else if (bind == STB_WEAK)
1297 flags = BSF_WEAK;
1298 else
1300 /* Leave it up to the processor backend. */
1303 if (sym.st_shndx == SHN_UNDEF)
1304 sec = bfd_und_section_ptr;
1305 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1307 sec = section_from_elf_index (abfd, sym.st_shndx);
1308 if (sec == NULL)
1309 sec = bfd_abs_section_ptr;
1310 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1311 value -= sec->vma;
1313 else if (sym.st_shndx == SHN_ABS)
1314 sec = bfd_abs_section_ptr;
1315 else if (sym.st_shndx == SHN_COMMON)
1317 sec = bfd_com_section_ptr;
1318 /* What ELF calls the size we call the value. What ELF
1319 calls the value we call the alignment. */
1320 value = sym.st_size;
1322 else
1324 /* Leave it up to the processor backend. */
1327 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1328 if (name == (const char *) NULL)
1329 goto error_return;
1331 if (add_symbol_hook)
1333 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1334 &value))
1335 goto error_return;
1337 /* The hook function sets the name to NULL if this symbol
1338 should be skipped for some reason. */
1339 if (name == (const char *) NULL)
1340 continue;
1343 /* Sanity check that all possibilities were handled. */
1344 if (sec == (asection *) NULL)
1346 bfd_set_error (bfd_error_bad_value);
1347 goto error_return;
1350 if (bfd_is_und_section (sec)
1351 || bfd_is_com_section (sec))
1352 definition = false;
1353 else
1354 definition = true;
1356 size_change_ok = false;
1357 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1358 old_alignment = 0;
1359 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1361 Elf_Internal_Versym iver;
1362 unsigned int vernum = 0;
1363 boolean override;
1365 if (ever != NULL)
1367 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1368 vernum = iver.vs_vers & VERSYM_VERSION;
1370 /* If this is a hidden symbol, or if it is not version
1371 1, we append the version name to the symbol name.
1372 However, we do not modify a non-hidden absolute
1373 symbol, because it might be the version symbol
1374 itself. FIXME: What if it isn't? */
1375 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1376 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1378 const char *verstr;
1379 int namelen, newlen;
1380 char *newname, *p;
1382 if (sym.st_shndx != SHN_UNDEF)
1384 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1386 (*_bfd_error_handler)
1387 (_("%s: %s: invalid version %u (max %d)"),
1388 bfd_get_filename (abfd), name, vernum,
1389 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1390 bfd_set_error (bfd_error_bad_value);
1391 goto error_return;
1393 else if (vernum > 1)
1394 verstr =
1395 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1396 else
1397 verstr = "";
1399 else
1401 /* We cannot simply test for the number of
1402 entries in the VERNEED section since the
1403 numbers for the needed versions do not start
1404 at 0. */
1405 Elf_Internal_Verneed *t;
1407 verstr = NULL;
1408 for (t = elf_tdata (abfd)->verref;
1409 t != NULL;
1410 t = t->vn_nextref)
1412 Elf_Internal_Vernaux *a;
1414 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1416 if (a->vna_other == vernum)
1418 verstr = a->vna_nodename;
1419 break;
1422 if (a != NULL)
1423 break;
1425 if (verstr == NULL)
1427 (*_bfd_error_handler)
1428 (_("%s: %s: invalid needed version %d"),
1429 bfd_get_filename (abfd), name, vernum);
1430 bfd_set_error (bfd_error_bad_value);
1431 goto error_return;
1435 namelen = strlen (name);
1436 newlen = namelen + strlen (verstr) + 2;
1437 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1438 ++newlen;
1440 newname = (char *) bfd_alloc (abfd, newlen);
1441 if (newname == NULL)
1442 goto error_return;
1443 strcpy (newname, name);
1444 p = newname + namelen;
1445 *p++ = ELF_VER_CHR;
1446 /* If this is a defined non-hidden version symbol,
1447 we add another @ to the name. This indicates the
1448 default version of the symbol. */
1449 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1450 && sym.st_shndx != SHN_UNDEF)
1451 *p++ = ELF_VER_CHR;
1452 strcpy (p, verstr);
1454 name = newname;
1458 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1459 sym_hash, &override, &type_change_ok,
1460 &size_change_ok))
1461 goto error_return;
1463 if (override)
1464 definition = false;
1466 h = *sym_hash;
1467 while (h->root.type == bfd_link_hash_indirect
1468 || h->root.type == bfd_link_hash_warning)
1469 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1471 /* Remember the old alignment if this is a common symbol, so
1472 that we don't reduce the alignment later on. We can't
1473 check later, because _bfd_generic_link_add_one_symbol
1474 will set a default for the alignment which we want to
1475 override. */
1476 if (h->root.type == bfd_link_hash_common)
1477 old_alignment = h->root.u.c.p->alignment_power;
1479 if (elf_tdata (abfd)->verdef != NULL
1480 && ! override
1481 && vernum > 1
1482 && definition)
1483 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1486 if (! (_bfd_generic_link_add_one_symbol
1487 (info, abfd, name, flags, sec, value, (const char *) NULL,
1488 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1489 goto error_return;
1491 h = *sym_hash;
1492 while (h->root.type == bfd_link_hash_indirect
1493 || h->root.type == bfd_link_hash_warning)
1494 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1495 *sym_hash = h;
1497 new_weakdef = false;
1498 if (dynamic
1499 && definition
1500 && (flags & BSF_WEAK) != 0
1501 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1502 && info->hash->creator->flavour == bfd_target_elf_flavour
1503 && h->weakdef == NULL)
1505 /* Keep a list of all weak defined non function symbols from
1506 a dynamic object, using the weakdef field. Later in this
1507 function we will set the weakdef field to the correct
1508 value. We only put non-function symbols from dynamic
1509 objects on this list, because that happens to be the only
1510 time we need to know the normal symbol corresponding to a
1511 weak symbol, and the information is time consuming to
1512 figure out. If the weakdef field is not already NULL,
1513 then this symbol was already defined by some previous
1514 dynamic object, and we will be using that previous
1515 definition anyhow. */
1517 h->weakdef = weaks;
1518 weaks = h;
1519 new_weakdef = true;
1522 /* Set the alignment of a common symbol. */
1523 if (sym.st_shndx == SHN_COMMON
1524 && h->root.type == bfd_link_hash_common)
1526 unsigned int align;
1528 align = bfd_log2 (sym.st_value);
1529 if (align > old_alignment)
1530 h->root.u.c.p->alignment_power = align;
1533 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1535 int old_flags;
1536 boolean dynsym;
1537 int new_flag;
1539 /* Remember the symbol size and type. */
1540 if (sym.st_size != 0
1541 && (definition || h->size == 0))
1543 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1544 (*_bfd_error_handler)
1545 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1546 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1547 bfd_get_filename (abfd));
1549 h->size = sym.st_size;
1552 /* If this is a common symbol, then we always want H->SIZE
1553 to be the size of the common symbol. The code just above
1554 won't fix the size if a common symbol becomes larger. We
1555 don't warn about a size change here, because that is
1556 covered by --warn-common. */
1557 if (h->root.type == bfd_link_hash_common)
1558 h->size = h->root.u.c.size;
1560 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1561 && (definition || h->type == STT_NOTYPE))
1563 if (h->type != STT_NOTYPE
1564 && h->type != ELF_ST_TYPE (sym.st_info)
1565 && ! type_change_ok)
1566 (*_bfd_error_handler)
1567 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1568 name, h->type, ELF_ST_TYPE (sym.st_info),
1569 bfd_get_filename (abfd));
1571 h->type = ELF_ST_TYPE (sym.st_info);
1574 /* If st_other has a processor-specific meaning, specific code
1575 might be needed here. */
1576 if (sym.st_other != 0)
1578 /* Combine visibilities, using the most constraining one. */
1579 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1580 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1582 if (symvis && (hvis > symvis || hvis == 0))
1583 h->other = sym.st_other;
1585 /* If neither has visibility, use the st_other of the
1586 definition. This is an arbitrary choice, since the
1587 other bits have no general meaning. */
1588 if (!symvis && !hvis
1589 && (definition || h->other == 0))
1590 h->other = sym.st_other;
1593 /* Set a flag in the hash table entry indicating the type of
1594 reference or definition we just found. Keep a count of
1595 the number of dynamic symbols we find. A dynamic symbol
1596 is one which is referenced or defined by both a regular
1597 object and a shared object. */
1598 old_flags = h->elf_link_hash_flags;
1599 dynsym = false;
1600 if (! dynamic)
1602 if (! definition)
1604 new_flag = ELF_LINK_HASH_REF_REGULAR;
1605 if (bind != STB_WEAK)
1606 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1608 else
1609 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1610 if (info->shared
1611 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1612 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1613 dynsym = true;
1615 else
1617 if (! definition)
1618 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1619 else
1620 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1621 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1622 | ELF_LINK_HASH_REF_REGULAR)) != 0
1623 || (h->weakdef != NULL
1624 && ! new_weakdef
1625 && h->weakdef->dynindx != -1))
1626 dynsym = true;
1629 h->elf_link_hash_flags |= new_flag;
1631 /* If this symbol has a version, and it is the default
1632 version, we create an indirect symbol from the default
1633 name to the fully decorated name. This will cause
1634 external references which do not specify a version to be
1635 bound to this version of the symbol. */
1636 if (definition)
1638 char *p;
1640 p = strchr (name, ELF_VER_CHR);
1641 if (p != NULL && p[1] == ELF_VER_CHR)
1643 char *shortname;
1644 struct elf_link_hash_entry *hi;
1645 boolean override;
1647 shortname = bfd_hash_allocate (&info->hash->table,
1648 p - name + 1);
1649 if (shortname == NULL)
1650 goto error_return;
1651 strncpy (shortname, name, p - name);
1652 shortname[p - name] = '\0';
1654 /* We are going to create a new symbol. Merge it
1655 with any existing symbol with this name. For the
1656 purposes of the merge, act as though we were
1657 defining the symbol we just defined, although we
1658 actually going to define an indirect symbol. */
1659 type_change_ok = false;
1660 size_change_ok = false;
1661 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1662 &value, &hi, &override,
1663 &type_change_ok, &size_change_ok))
1664 goto error_return;
1666 if (! override)
1668 if (! (_bfd_generic_link_add_one_symbol
1669 (info, abfd, shortname, BSF_INDIRECT,
1670 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1671 collect, (struct bfd_link_hash_entry **) &hi)))
1672 goto error_return;
1674 else
1676 /* In this case the symbol named SHORTNAME is
1677 overriding the indirect symbol we want to
1678 add. We were planning on making SHORTNAME an
1679 indirect symbol referring to NAME. SHORTNAME
1680 is the name without a version. NAME is the
1681 fully versioned name, and it is the default
1682 version.
1684 Overriding means that we already saw a
1685 definition for the symbol SHORTNAME in a
1686 regular object, and it is overriding the
1687 symbol defined in the dynamic object.
1689 When this happens, we actually want to change
1690 NAME, the symbol we just added, to refer to
1691 SHORTNAME. This will cause references to
1692 NAME in the shared object to become
1693 references to SHORTNAME in the regular
1694 object. This is what we expect when we
1695 override a function in a shared object: that
1696 the references in the shared object will be
1697 mapped to the definition in the regular
1698 object. */
1700 while (hi->root.type == bfd_link_hash_indirect
1701 || hi->root.type == bfd_link_hash_warning)
1702 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1704 h->root.type = bfd_link_hash_indirect;
1705 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1706 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1708 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1709 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1710 if (hi->elf_link_hash_flags
1711 & (ELF_LINK_HASH_REF_REGULAR
1712 | ELF_LINK_HASH_DEF_REGULAR))
1714 if (! _bfd_elf_link_record_dynamic_symbol (info,
1715 hi))
1716 goto error_return;
1720 /* Now set HI to H, so that the following code
1721 will set the other fields correctly. */
1722 hi = h;
1725 /* If there is a duplicate definition somewhere,
1726 then HI may not point to an indirect symbol. We
1727 will have reported an error to the user in that
1728 case. */
1730 if (hi->root.type == bfd_link_hash_indirect)
1732 struct elf_link_hash_entry *ht;
1734 /* If the symbol became indirect, then we assume
1735 that we have not seen a definition before. */
1736 BFD_ASSERT ((hi->elf_link_hash_flags
1737 & (ELF_LINK_HASH_DEF_DYNAMIC
1738 | ELF_LINK_HASH_DEF_REGULAR))
1739 == 0);
1741 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1742 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1744 /* See if the new flags lead us to realize that
1745 the symbol must be dynamic. */
1746 if (! dynsym)
1748 if (! dynamic)
1750 if (info->shared
1751 || ((hi->elf_link_hash_flags
1752 & ELF_LINK_HASH_REF_DYNAMIC)
1753 != 0))
1754 dynsym = true;
1756 else
1758 if ((hi->elf_link_hash_flags
1759 & ELF_LINK_HASH_REF_REGULAR) != 0)
1760 dynsym = true;
1765 /* We also need to define an indirection from the
1766 nondefault version of the symbol. */
1768 shortname = bfd_hash_allocate (&info->hash->table,
1769 strlen (name));
1770 if (shortname == NULL)
1771 goto error_return;
1772 strncpy (shortname, name, p - name);
1773 strcpy (shortname + (p - name), p + 1);
1775 /* Once again, merge with any existing symbol. */
1776 type_change_ok = false;
1777 size_change_ok = false;
1778 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1779 &value, &hi, &override,
1780 &type_change_ok, &size_change_ok))
1781 goto error_return;
1783 if (override)
1785 /* Here SHORTNAME is a versioned name, so we
1786 don't expect to see the type of override we
1787 do in the case above. */
1788 (*_bfd_error_handler)
1789 (_("%s: warning: unexpected redefinition of `%s'"),
1790 bfd_get_filename (abfd), shortname);
1792 else
1794 if (! (_bfd_generic_link_add_one_symbol
1795 (info, abfd, shortname, BSF_INDIRECT,
1796 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1797 collect, (struct bfd_link_hash_entry **) &hi)))
1798 goto error_return;
1800 /* If there is a duplicate definition somewhere,
1801 then HI may not point to an indirect symbol.
1802 We will have reported an error to the user in
1803 that case. */
1805 if (hi->root.type == bfd_link_hash_indirect)
1807 /* If the symbol became indirect, then we
1808 assume that we have not seen a definition
1809 before. */
1810 BFD_ASSERT ((hi->elf_link_hash_flags
1811 & (ELF_LINK_HASH_DEF_DYNAMIC
1812 | ELF_LINK_HASH_DEF_REGULAR))
1813 == 0);
1815 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1817 /* See if the new flags lead us to realize
1818 that the symbol must be dynamic. */
1819 if (! dynsym)
1821 if (! dynamic)
1823 if (info->shared
1824 || ((hi->elf_link_hash_flags
1825 & ELF_LINK_HASH_REF_DYNAMIC)
1826 != 0))
1827 dynsym = true;
1829 else
1831 if ((hi->elf_link_hash_flags
1832 & ELF_LINK_HASH_REF_REGULAR) != 0)
1833 dynsym = true;
1841 if (dynsym && h->dynindx == -1)
1843 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1844 goto error_return;
1845 if (h->weakdef != NULL
1846 && ! new_weakdef
1847 && h->weakdef->dynindx == -1)
1849 if (! _bfd_elf_link_record_dynamic_symbol (info,
1850 h->weakdef))
1851 goto error_return;
1854 else if (dynsym && h->dynindx != -1)
1855 /* If the symbol already has a dynamic index, but
1856 visibility says it should not be visible, turn it into
1857 a local symbol. */
1858 switch (ELF_ST_VISIBILITY (h->other))
1860 case STV_INTERNAL:
1861 case STV_HIDDEN:
1862 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1863 (*bed->elf_backend_hide_symbol) (h);
1864 break;
1869 /* Now set the weakdefs field correctly for all the weak defined
1870 symbols we found. The only way to do this is to search all the
1871 symbols. Since we only need the information for non functions in
1872 dynamic objects, that's the only time we actually put anything on
1873 the list WEAKS. We need this information so that if a regular
1874 object refers to a symbol defined weakly in a dynamic object, the
1875 real symbol in the dynamic object is also put in the dynamic
1876 symbols; we also must arrange for both symbols to point to the
1877 same memory location. We could handle the general case of symbol
1878 aliasing, but a general symbol alias can only be generated in
1879 assembler code, handling it correctly would be very time
1880 consuming, and other ELF linkers don't handle general aliasing
1881 either. */
1882 while (weaks != NULL)
1884 struct elf_link_hash_entry *hlook;
1885 asection *slook;
1886 bfd_vma vlook;
1887 struct elf_link_hash_entry **hpp;
1888 struct elf_link_hash_entry **hppend;
1890 hlook = weaks;
1891 weaks = hlook->weakdef;
1892 hlook->weakdef = NULL;
1894 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1895 || hlook->root.type == bfd_link_hash_defweak
1896 || hlook->root.type == bfd_link_hash_common
1897 || hlook->root.type == bfd_link_hash_indirect);
1898 slook = hlook->root.u.def.section;
1899 vlook = hlook->root.u.def.value;
1901 hpp = elf_sym_hashes (abfd);
1902 hppend = hpp + extsymcount;
1903 for (; hpp < hppend; hpp++)
1905 struct elf_link_hash_entry *h;
1907 h = *hpp;
1908 if (h != NULL && h != hlook
1909 && h->root.type == bfd_link_hash_defined
1910 && h->root.u.def.section == slook
1911 && h->root.u.def.value == vlook)
1913 hlook->weakdef = h;
1915 /* If the weak definition is in the list of dynamic
1916 symbols, make sure the real definition is put there
1917 as well. */
1918 if (hlook->dynindx != -1
1919 && h->dynindx == -1)
1921 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1922 goto error_return;
1925 /* If the real definition is in the list of dynamic
1926 symbols, make sure the weak definition is put there
1927 as well. If we don't do this, then the dynamic
1928 loader might not merge the entries for the real
1929 definition and the weak definition. */
1930 if (h->dynindx != -1
1931 && hlook->dynindx == -1)
1933 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1934 goto error_return;
1937 break;
1942 if (buf != NULL)
1944 free (buf);
1945 buf = NULL;
1948 if (extversym != NULL)
1950 free (extversym);
1951 extversym = NULL;
1954 /* If this object is the same format as the output object, and it is
1955 not a shared library, then let the backend look through the
1956 relocs.
1958 This is required to build global offset table entries and to
1959 arrange for dynamic relocs. It is not required for the
1960 particular common case of linking non PIC code, even when linking
1961 against shared libraries, but unfortunately there is no way of
1962 knowing whether an object file has been compiled PIC or not.
1963 Looking through the relocs is not particularly time consuming.
1964 The problem is that we must either (1) keep the relocs in memory,
1965 which causes the linker to require additional runtime memory or
1966 (2) read the relocs twice from the input file, which wastes time.
1967 This would be a good case for using mmap.
1969 I have no idea how to handle linking PIC code into a file of a
1970 different format. It probably can't be done. */
1971 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1972 if (! dynamic
1973 && abfd->xvec == info->hash->creator
1974 && check_relocs != NULL)
1976 asection *o;
1978 for (o = abfd->sections; o != NULL; o = o->next)
1980 Elf_Internal_Rela *internal_relocs;
1981 boolean ok;
1983 if ((o->flags & SEC_RELOC) == 0
1984 || o->reloc_count == 0
1985 || ((info->strip == strip_all || info->strip == strip_debugger)
1986 && (o->flags & SEC_DEBUGGING) != 0)
1987 || bfd_is_abs_section (o->output_section))
1988 continue;
1990 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1991 (abfd, o, (PTR) NULL,
1992 (Elf_Internal_Rela *) NULL,
1993 info->keep_memory));
1994 if (internal_relocs == NULL)
1995 goto error_return;
1997 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1999 if (! info->keep_memory)
2000 free (internal_relocs);
2002 if (! ok)
2003 goto error_return;
2007 /* If this is a non-traditional, non-relocateable link, try to
2008 optimize the handling of the .stab/.stabstr sections. */
2009 if (! dynamic
2010 && ! info->relocateable
2011 && ! info->traditional_format
2012 && info->hash->creator->flavour == bfd_target_elf_flavour
2013 && (info->strip != strip_all && info->strip != strip_debugger))
2015 asection *stab, *stabstr;
2017 stab = bfd_get_section_by_name (abfd, ".stab");
2018 if (stab != NULL)
2020 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2022 if (stabstr != NULL)
2024 struct bfd_elf_section_data *secdata;
2026 secdata = elf_section_data (stab);
2027 if (! _bfd_link_section_stabs (abfd,
2028 &elf_hash_table (info)->stab_info,
2029 stab, stabstr,
2030 &secdata->stab_info))
2031 goto error_return;
2036 return true;
2038 error_return:
2039 if (buf != NULL)
2040 free (buf);
2041 if (dynbuf != NULL)
2042 free (dynbuf);
2043 if (dynver != NULL)
2044 free (dynver);
2045 if (extversym != NULL)
2046 free (extversym);
2047 return false;
2050 /* Create some sections which will be filled in with dynamic linking
2051 information. ABFD is an input file which requires dynamic sections
2052 to be created. The dynamic sections take up virtual memory space
2053 when the final executable is run, so we need to create them before
2054 addresses are assigned to the output sections. We work out the
2055 actual contents and size of these sections later. */
2057 boolean
2058 elf_link_create_dynamic_sections (abfd, info)
2059 bfd *abfd;
2060 struct bfd_link_info *info;
2062 flagword flags;
2063 register asection *s;
2064 struct elf_link_hash_entry *h;
2065 struct elf_backend_data *bed;
2067 if (elf_hash_table (info)->dynamic_sections_created)
2068 return true;
2070 /* Make sure that all dynamic sections use the same input BFD. */
2071 if (elf_hash_table (info)->dynobj == NULL)
2072 elf_hash_table (info)->dynobj = abfd;
2073 else
2074 abfd = elf_hash_table (info)->dynobj;
2076 /* Note that we set the SEC_IN_MEMORY flag for all of these
2077 sections. */
2078 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2079 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2081 /* A dynamically linked executable has a .interp section, but a
2082 shared library does not. */
2083 if (! info->shared)
2085 s = bfd_make_section (abfd, ".interp");
2086 if (s == NULL
2087 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2088 return false;
2091 /* Create sections to hold version informations. These are removed
2092 if they are not needed. */
2093 s = bfd_make_section (abfd, ".gnu.version_d");
2094 if (s == NULL
2095 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2096 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2097 return false;
2099 s = bfd_make_section (abfd, ".gnu.version");
2100 if (s == NULL
2101 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2102 || ! bfd_set_section_alignment (abfd, s, 1))
2103 return false;
2105 s = bfd_make_section (abfd, ".gnu.version_r");
2106 if (s == NULL
2107 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2108 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2109 return false;
2111 s = bfd_make_section (abfd, ".dynsym");
2112 if (s == NULL
2113 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2114 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2115 return false;
2117 s = bfd_make_section (abfd, ".dynstr");
2118 if (s == NULL
2119 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2120 return false;
2122 /* Create a strtab to hold the dynamic symbol names. */
2123 if (elf_hash_table (info)->dynstr == NULL)
2125 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2126 if (elf_hash_table (info)->dynstr == NULL)
2127 return false;
2130 s = bfd_make_section (abfd, ".dynamic");
2131 if (s == NULL
2132 || ! bfd_set_section_flags (abfd, s, flags)
2133 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2134 return false;
2136 /* The special symbol _DYNAMIC is always set to the start of the
2137 .dynamic section. This call occurs before we have processed the
2138 symbols for any dynamic object, so we don't have to worry about
2139 overriding a dynamic definition. We could set _DYNAMIC in a
2140 linker script, but we only want to define it if we are, in fact,
2141 creating a .dynamic section. We don't want to define it if there
2142 is no .dynamic section, since on some ELF platforms the start up
2143 code examines it to decide how to initialize the process. */
2144 h = NULL;
2145 if (! (_bfd_generic_link_add_one_symbol
2146 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2147 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2148 (struct bfd_link_hash_entry **) &h)))
2149 return false;
2150 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2151 h->type = STT_OBJECT;
2153 if (info->shared
2154 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2155 return false;
2157 bed = get_elf_backend_data (abfd);
2159 s = bfd_make_section (abfd, ".hash");
2160 if (s == NULL
2161 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2162 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2163 return false;
2164 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2166 /* Let the backend create the rest of the sections. This lets the
2167 backend set the right flags. The backend will normally create
2168 the .got and .plt sections. */
2169 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2170 return false;
2172 elf_hash_table (info)->dynamic_sections_created = true;
2174 return true;
2177 /* Add an entry to the .dynamic table. */
2179 boolean
2180 elf_add_dynamic_entry (info, tag, val)
2181 struct bfd_link_info *info;
2182 bfd_vma tag;
2183 bfd_vma val;
2185 Elf_Internal_Dyn dyn;
2186 bfd *dynobj;
2187 asection *s;
2188 size_t newsize;
2189 bfd_byte *newcontents;
2191 dynobj = elf_hash_table (info)->dynobj;
2193 s = bfd_get_section_by_name (dynobj, ".dynamic");
2194 BFD_ASSERT (s != NULL);
2196 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2197 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2198 if (newcontents == NULL)
2199 return false;
2201 dyn.d_tag = tag;
2202 dyn.d_un.d_val = val;
2203 elf_swap_dyn_out (dynobj, &dyn,
2204 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2206 s->_raw_size = newsize;
2207 s->contents = newcontents;
2209 return true;
2212 /* Record a new local dynamic symbol. */
2214 boolean
2215 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2216 struct bfd_link_info *info;
2217 bfd *input_bfd;
2218 long input_indx;
2220 struct elf_link_local_dynamic_entry *entry;
2221 struct elf_link_hash_table *eht;
2222 struct bfd_strtab_hash *dynstr;
2223 Elf_External_Sym esym;
2224 unsigned long dynstr_index;
2225 char *name;
2227 /* See if the entry exists already. */
2228 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2229 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2230 return true;
2232 entry = (struct elf_link_local_dynamic_entry *)
2233 bfd_alloc (input_bfd, sizeof (*entry));
2234 if (entry == NULL)
2235 return false;
2237 /* Go find the symbol, so that we can find it's name. */
2238 if (bfd_seek (input_bfd,
2239 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2240 + input_indx * sizeof (Elf_External_Sym)),
2241 SEEK_SET) != 0
2242 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2243 != sizeof (Elf_External_Sym)))
2244 return false;
2245 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2247 name = (bfd_elf_string_from_elf_section
2248 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2249 entry->isym.st_name));
2251 dynstr = elf_hash_table (info)->dynstr;
2252 if (dynstr == NULL)
2254 /* Create a strtab to hold the dynamic symbol names. */
2255 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2256 if (dynstr == NULL)
2257 return false;
2260 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2261 if (dynstr_index == (unsigned long) -1)
2262 return false;
2263 entry->isym.st_name = dynstr_index;
2265 eht = elf_hash_table (info);
2267 entry->next = eht->dynlocal;
2268 eht->dynlocal = entry;
2269 entry->input_bfd = input_bfd;
2270 entry->input_indx = input_indx;
2271 eht->dynsymcount++;
2273 /* Whatever binding the symbol had before, it's now local. */
2274 entry->isym.st_info
2275 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2277 /* The dynindx will be set at the end of size_dynamic_sections. */
2279 return true;
2283 /* Read and swap the relocs from the section indicated by SHDR. This
2284 may be either a REL or a RELA section. The relocations are
2285 translated into RELA relocations and stored in INTERNAL_RELOCS,
2286 which should have already been allocated to contain enough space.
2287 The EXTERNAL_RELOCS are a buffer where the external form of the
2288 relocations should be stored.
2290 Returns false if something goes wrong. */
2292 static boolean
2293 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2294 internal_relocs)
2295 bfd *abfd;
2296 Elf_Internal_Shdr *shdr;
2297 PTR external_relocs;
2298 Elf_Internal_Rela *internal_relocs;
2300 struct elf_backend_data *bed;
2302 /* If there aren't any relocations, that's OK. */
2303 if (!shdr)
2304 return true;
2306 /* Position ourselves at the start of the section. */
2307 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2308 return false;
2310 /* Read the relocations. */
2311 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2312 != shdr->sh_size)
2313 return false;
2315 bed = get_elf_backend_data (abfd);
2317 /* Convert the external relocations to the internal format. */
2318 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2320 Elf_External_Rel *erel;
2321 Elf_External_Rel *erelend;
2322 Elf_Internal_Rela *irela;
2323 Elf_Internal_Rel *irel;
2325 erel = (Elf_External_Rel *) external_relocs;
2326 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2327 irela = internal_relocs;
2328 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2329 * sizeof (Elf_Internal_Rel)));
2330 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2332 unsigned char i;
2334 if (bed->s->swap_reloc_in)
2335 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2336 else
2337 elf_swap_reloc_in (abfd, erel, irel);
2339 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2341 irela[i].r_offset = irel[i].r_offset;
2342 irela[i].r_info = irel[i].r_info;
2343 irela[i].r_addend = 0;
2347 else
2349 Elf_External_Rela *erela;
2350 Elf_External_Rela *erelaend;
2351 Elf_Internal_Rela *irela;
2353 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2355 erela = (Elf_External_Rela *) external_relocs;
2356 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2357 irela = internal_relocs;
2358 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2360 if (bed->s->swap_reloca_in)
2361 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2362 else
2363 elf_swap_reloca_in (abfd, erela, irela);
2367 return true;
2370 /* Read and swap the relocs for a section O. They may have been
2371 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2372 not NULL, they are used as buffers to read into. They are known to
2373 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2374 the return value is allocated using either malloc or bfd_alloc,
2375 according to the KEEP_MEMORY argument. If O has two relocation
2376 sections (both REL and RELA relocations), then the REL_HDR
2377 relocations will appear first in INTERNAL_RELOCS, followed by the
2378 REL_HDR2 relocations. */
2380 Elf_Internal_Rela *
2381 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2382 keep_memory)
2383 bfd *abfd;
2384 asection *o;
2385 PTR external_relocs;
2386 Elf_Internal_Rela *internal_relocs;
2387 boolean keep_memory;
2389 Elf_Internal_Shdr *rel_hdr;
2390 PTR alloc1 = NULL;
2391 Elf_Internal_Rela *alloc2 = NULL;
2392 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2394 if (elf_section_data (o)->relocs != NULL)
2395 return elf_section_data (o)->relocs;
2397 if (o->reloc_count == 0)
2398 return NULL;
2400 rel_hdr = &elf_section_data (o)->rel_hdr;
2402 if (internal_relocs == NULL)
2404 size_t size;
2406 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2407 * sizeof (Elf_Internal_Rela));
2408 if (keep_memory)
2409 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2410 else
2411 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2412 if (internal_relocs == NULL)
2413 goto error_return;
2416 if (external_relocs == NULL)
2418 size_t size = (size_t) rel_hdr->sh_size;
2420 if (elf_section_data (o)->rel_hdr2)
2421 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2422 alloc1 = (PTR) bfd_malloc (size);
2423 if (alloc1 == NULL)
2424 goto error_return;
2425 external_relocs = alloc1;
2428 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2429 external_relocs,
2430 internal_relocs))
2431 goto error_return;
2432 if (!elf_link_read_relocs_from_section
2433 (abfd,
2434 elf_section_data (o)->rel_hdr2,
2435 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2436 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2437 * bed->s->int_rels_per_ext_rel)))
2438 goto error_return;
2440 /* Cache the results for next time, if we can. */
2441 if (keep_memory)
2442 elf_section_data (o)->relocs = internal_relocs;
2444 if (alloc1 != NULL)
2445 free (alloc1);
2447 /* Don't free alloc2, since if it was allocated we are passing it
2448 back (under the name of internal_relocs). */
2450 return internal_relocs;
2452 error_return:
2453 if (alloc1 != NULL)
2454 free (alloc1);
2455 if (alloc2 != NULL)
2456 free (alloc2);
2457 return NULL;
2461 /* Record an assignment to a symbol made by a linker script. We need
2462 this in case some dynamic object refers to this symbol. */
2464 /*ARGSUSED*/
2465 boolean
2466 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2467 bfd *output_bfd ATTRIBUTE_UNUSED;
2468 struct bfd_link_info *info;
2469 const char *name;
2470 boolean provide;
2472 struct elf_link_hash_entry *h;
2474 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2475 return true;
2477 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2478 if (h == NULL)
2479 return false;
2481 if (h->root.type == bfd_link_hash_new)
2482 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2484 /* If this symbol is being provided by the linker script, and it is
2485 currently defined by a dynamic object, but not by a regular
2486 object, then mark it as undefined so that the generic linker will
2487 force the correct value. */
2488 if (provide
2489 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2490 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2491 h->root.type = bfd_link_hash_undefined;
2493 /* If this symbol is not being provided by the linker script, and it is
2494 currently defined by a dynamic object, but not by a regular object,
2495 then clear out any version information because the symbol will not be
2496 associated with the dynamic object any more. */
2497 if (!provide
2498 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2499 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2500 h->verinfo.verdef = NULL;
2502 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2504 /* When possible, keep the original type of the symbol */
2505 if (h->type == STT_NOTYPE)
2506 h->type = STT_OBJECT;
2508 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2509 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2510 || info->shared)
2511 && h->dynindx == -1)
2513 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2514 return false;
2516 /* If this is a weak defined symbol, and we know a corresponding
2517 real symbol from the same dynamic object, make sure the real
2518 symbol is also made into a dynamic symbol. */
2519 if (h->weakdef != NULL
2520 && h->weakdef->dynindx == -1)
2522 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2523 return false;
2527 return true;
2530 /* This structure is used to pass information to
2531 elf_link_assign_sym_version. */
2533 struct elf_assign_sym_version_info
2535 /* Output BFD. */
2536 bfd *output_bfd;
2537 /* General link information. */
2538 struct bfd_link_info *info;
2539 /* Version tree. */
2540 struct bfd_elf_version_tree *verdefs;
2541 /* Whether we are exporting all dynamic symbols. */
2542 boolean export_dynamic;
2543 /* Whether we had a failure. */
2544 boolean failed;
2547 /* This structure is used to pass information to
2548 elf_link_find_version_dependencies. */
2550 struct elf_find_verdep_info
2552 /* Output BFD. */
2553 bfd *output_bfd;
2554 /* General link information. */
2555 struct bfd_link_info *info;
2556 /* The number of dependencies. */
2557 unsigned int vers;
2558 /* Whether we had a failure. */
2559 boolean failed;
2562 /* Array used to determine the number of hash table buckets to use
2563 based on the number of symbols there are. If there are fewer than
2564 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2565 fewer than 37 we use 17 buckets, and so forth. We never use more
2566 than 32771 buckets. */
2568 static const size_t elf_buckets[] =
2570 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2571 16411, 32771, 0
2574 /* Compute bucket count for hashing table. We do not use a static set
2575 of possible tables sizes anymore. Instead we determine for all
2576 possible reasonable sizes of the table the outcome (i.e., the
2577 number of collisions etc) and choose the best solution. The
2578 weighting functions are not too simple to allow the table to grow
2579 without bounds. Instead one of the weighting factors is the size.
2580 Therefore the result is always a good payoff between few collisions
2581 (= short chain lengths) and table size. */
2582 static size_t
2583 compute_bucket_count (info)
2584 struct bfd_link_info *info;
2586 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2587 size_t best_size = 0;
2588 unsigned long int *hashcodes;
2589 unsigned long int *hashcodesp;
2590 unsigned long int i;
2592 /* Compute the hash values for all exported symbols. At the same
2593 time store the values in an array so that we could use them for
2594 optimizations. */
2595 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2596 * sizeof (unsigned long int));
2597 if (hashcodes == NULL)
2598 return 0;
2599 hashcodesp = hashcodes;
2601 /* Put all hash values in HASHCODES. */
2602 elf_link_hash_traverse (elf_hash_table (info),
2603 elf_collect_hash_codes, &hashcodesp);
2605 /* We have a problem here. The following code to optimize the table
2606 size requires an integer type with more the 32 bits. If
2607 BFD_HOST_U_64_BIT is set we know about such a type. */
2608 #ifdef BFD_HOST_U_64_BIT
2609 if (info->optimize == true)
2611 unsigned long int nsyms = hashcodesp - hashcodes;
2612 size_t minsize;
2613 size_t maxsize;
2614 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2615 unsigned long int *counts ;
2617 /* Possible optimization parameters: if we have NSYMS symbols we say
2618 that the hashing table must at least have NSYMS/4 and at most
2619 2*NSYMS buckets. */
2620 minsize = nsyms / 4;
2621 if (minsize == 0)
2622 minsize = 1;
2623 best_size = maxsize = nsyms * 2;
2625 /* Create array where we count the collisions in. We must use bfd_malloc
2626 since the size could be large. */
2627 counts = (unsigned long int *) bfd_malloc (maxsize
2628 * sizeof (unsigned long int));
2629 if (counts == NULL)
2631 free (hashcodes);
2632 return 0;
2635 /* Compute the "optimal" size for the hash table. The criteria is a
2636 minimal chain length. The minor criteria is (of course) the size
2637 of the table. */
2638 for (i = minsize; i < maxsize; ++i)
2640 /* Walk through the array of hashcodes and count the collisions. */
2641 BFD_HOST_U_64_BIT max;
2642 unsigned long int j;
2643 unsigned long int fact;
2645 memset (counts, '\0', i * sizeof (unsigned long int));
2647 /* Determine how often each hash bucket is used. */
2648 for (j = 0; j < nsyms; ++j)
2649 ++counts[hashcodes[j] % i];
2651 /* For the weight function we need some information about the
2652 pagesize on the target. This is information need not be 100%
2653 accurate. Since this information is not available (so far) we
2654 define it here to a reasonable default value. If it is crucial
2655 to have a better value some day simply define this value. */
2656 # ifndef BFD_TARGET_PAGESIZE
2657 # define BFD_TARGET_PAGESIZE (4096)
2658 # endif
2660 /* We in any case need 2 + NSYMS entries for the size values and
2661 the chains. */
2662 max = (2 + nsyms) * (ARCH_SIZE / 8);
2664 # if 1
2665 /* Variant 1: optimize for short chains. We add the squares
2666 of all the chain lengths (which favous many small chain
2667 over a few long chains). */
2668 for (j = 0; j < i; ++j)
2669 max += counts[j] * counts[j];
2671 /* This adds penalties for the overall size of the table. */
2672 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2673 max *= fact * fact;
2674 # else
2675 /* Variant 2: Optimize a lot more for small table. Here we
2676 also add squares of the size but we also add penalties for
2677 empty slots (the +1 term). */
2678 for (j = 0; j < i; ++j)
2679 max += (1 + counts[j]) * (1 + counts[j]);
2681 /* The overall size of the table is considered, but not as
2682 strong as in variant 1, where it is squared. */
2683 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2684 max *= fact;
2685 # endif
2687 /* Compare with current best results. */
2688 if (max < best_chlen)
2690 best_chlen = max;
2691 best_size = i;
2695 free (counts);
2697 else
2698 #endif /* defined (BFD_HOST_U_64_BIT) */
2700 /* This is the fallback solution if no 64bit type is available or if we
2701 are not supposed to spend much time on optimizations. We select the
2702 bucket count using a fixed set of numbers. */
2703 for (i = 0; elf_buckets[i] != 0; i++)
2705 best_size = elf_buckets[i];
2706 if (dynsymcount < elf_buckets[i + 1])
2707 break;
2711 /* Free the arrays we needed. */
2712 free (hashcodes);
2714 return best_size;
2717 /* Set up the sizes and contents of the ELF dynamic sections. This is
2718 called by the ELF linker emulation before_allocation routine. We
2719 must set the sizes of the sections before the linker sets the
2720 addresses of the various sections. */
2722 boolean
2723 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2724 export_dynamic, filter_shlib,
2725 auxiliary_filters, info, sinterpptr,
2726 verdefs)
2727 bfd *output_bfd;
2728 const char *soname;
2729 const char *rpath;
2730 boolean export_dynamic;
2731 const char *filter_shlib;
2732 const char * const *auxiliary_filters;
2733 struct bfd_link_info *info;
2734 asection **sinterpptr;
2735 struct bfd_elf_version_tree *verdefs;
2737 bfd_size_type soname_indx;
2738 bfd *dynobj;
2739 struct elf_backend_data *bed;
2740 struct elf_assign_sym_version_info asvinfo;
2742 *sinterpptr = NULL;
2744 soname_indx = (bfd_size_type) -1;
2746 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2747 return true;
2749 /* The backend may have to create some sections regardless of whether
2750 we're dynamic or not. */
2751 bed = get_elf_backend_data (output_bfd);
2752 if (bed->elf_backend_always_size_sections
2753 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2754 return false;
2756 dynobj = elf_hash_table (info)->dynobj;
2758 /* If there were no dynamic objects in the link, there is nothing to
2759 do here. */
2760 if (dynobj == NULL)
2761 return true;
2763 if (elf_hash_table (info)->dynamic_sections_created)
2765 struct elf_info_failed eif;
2766 struct elf_link_hash_entry *h;
2767 bfd_size_type strsize;
2769 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2770 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2772 if (soname != NULL)
2774 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2775 soname, true, true);
2776 if (soname_indx == (bfd_size_type) -1
2777 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2778 return false;
2781 if (info->symbolic)
2783 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2784 return false;
2787 if (rpath != NULL)
2789 bfd_size_type indx;
2791 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2792 true, true);
2793 if (indx == (bfd_size_type) -1
2794 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2795 return false;
2798 if (filter_shlib != NULL)
2800 bfd_size_type indx;
2802 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2803 filter_shlib, true, true);
2804 if (indx == (bfd_size_type) -1
2805 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2806 return false;
2809 if (auxiliary_filters != NULL)
2811 const char * const *p;
2813 for (p = auxiliary_filters; *p != NULL; p++)
2815 bfd_size_type indx;
2817 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2818 *p, true, true);
2819 if (indx == (bfd_size_type) -1
2820 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2821 return false;
2825 /* If we are supposed to export all symbols into the dynamic symbol
2826 table (this is not the normal case), then do so. */
2827 if (export_dynamic)
2829 struct elf_info_failed eif;
2831 eif.failed = false;
2832 eif.info = info;
2833 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2834 (PTR) &eif);
2835 if (eif.failed)
2836 return false;
2839 /* Attach all the symbols to their version information. */
2840 asvinfo.output_bfd = output_bfd;
2841 asvinfo.info = info;
2842 asvinfo.verdefs = verdefs;
2843 asvinfo.export_dynamic = export_dynamic;
2844 asvinfo.failed = false;
2846 elf_link_hash_traverse (elf_hash_table (info),
2847 elf_link_assign_sym_version,
2848 (PTR) &asvinfo);
2849 if (asvinfo.failed)
2850 return false;
2852 /* Find all symbols which were defined in a dynamic object and make
2853 the backend pick a reasonable value for them. */
2854 eif.failed = false;
2855 eif.info = info;
2856 elf_link_hash_traverse (elf_hash_table (info),
2857 elf_adjust_dynamic_symbol,
2858 (PTR) &eif);
2859 if (eif.failed)
2860 return false;
2862 /* Add some entries to the .dynamic section. We fill in some of the
2863 values later, in elf_bfd_final_link, but we must add the entries
2864 now so that we know the final size of the .dynamic section. */
2866 /* If there are initialization and/or finalization functions to
2867 call then add the corresponding DT_INIT/DT_FINI entries. */
2868 h = (info->init_function
2869 ? elf_link_hash_lookup (elf_hash_table (info),
2870 info->init_function, false,
2871 false, false)
2872 : NULL);
2873 if (h != NULL
2874 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2875 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2877 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2878 return false;
2880 h = (info->fini_function
2881 ? elf_link_hash_lookup (elf_hash_table (info),
2882 info->fini_function, false,
2883 false, false)
2884 : NULL);
2885 if (h != NULL
2886 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2887 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2889 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2890 return false;
2893 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2894 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2895 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2896 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2897 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2898 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2899 sizeof (Elf_External_Sym)))
2900 return false;
2903 /* The backend must work out the sizes of all the other dynamic
2904 sections. */
2905 if (bed->elf_backend_size_dynamic_sections
2906 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2907 return false;
2909 if (elf_hash_table (info)->dynamic_sections_created)
2911 size_t dynsymcount;
2912 asection *s;
2913 size_t bucketcount = 0;
2914 Elf_Internal_Sym isym;
2915 size_t hash_entry_size;
2917 /* Set up the version definition section. */
2918 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2919 BFD_ASSERT (s != NULL);
2921 /* We may have created additional version definitions if we are
2922 just linking a regular application. */
2923 verdefs = asvinfo.verdefs;
2925 if (verdefs == NULL)
2926 _bfd_strip_section_from_output (info, s);
2927 else
2929 unsigned int cdefs;
2930 bfd_size_type size;
2931 struct bfd_elf_version_tree *t;
2932 bfd_byte *p;
2933 Elf_Internal_Verdef def;
2934 Elf_Internal_Verdaux defaux;
2936 cdefs = 0;
2937 size = 0;
2939 /* Make space for the base version. */
2940 size += sizeof (Elf_External_Verdef);
2941 size += sizeof (Elf_External_Verdaux);
2942 ++cdefs;
2944 for (t = verdefs; t != NULL; t = t->next)
2946 struct bfd_elf_version_deps *n;
2948 size += sizeof (Elf_External_Verdef);
2949 size += sizeof (Elf_External_Verdaux);
2950 ++cdefs;
2952 for (n = t->deps; n != NULL; n = n->next)
2953 size += sizeof (Elf_External_Verdaux);
2956 s->_raw_size = size;
2957 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2958 if (s->contents == NULL && s->_raw_size != 0)
2959 return false;
2961 /* Fill in the version definition section. */
2963 p = s->contents;
2965 def.vd_version = VER_DEF_CURRENT;
2966 def.vd_flags = VER_FLG_BASE;
2967 def.vd_ndx = 1;
2968 def.vd_cnt = 1;
2969 def.vd_aux = sizeof (Elf_External_Verdef);
2970 def.vd_next = (sizeof (Elf_External_Verdef)
2971 + sizeof (Elf_External_Verdaux));
2973 if (soname_indx != (bfd_size_type) -1)
2975 def.vd_hash = bfd_elf_hash (soname);
2976 defaux.vda_name = soname_indx;
2978 else
2980 const char *name;
2981 bfd_size_type indx;
2983 name = output_bfd->filename;
2984 def.vd_hash = bfd_elf_hash (name);
2985 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2986 name, true, false);
2987 if (indx == (bfd_size_type) -1)
2988 return false;
2989 defaux.vda_name = indx;
2991 defaux.vda_next = 0;
2993 _bfd_elf_swap_verdef_out (output_bfd, &def,
2994 (Elf_External_Verdef *)p);
2995 p += sizeof (Elf_External_Verdef);
2996 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2997 (Elf_External_Verdaux *) p);
2998 p += sizeof (Elf_External_Verdaux);
3000 for (t = verdefs; t != NULL; t = t->next)
3002 unsigned int cdeps;
3003 struct bfd_elf_version_deps *n;
3004 struct elf_link_hash_entry *h;
3006 cdeps = 0;
3007 for (n = t->deps; n != NULL; n = n->next)
3008 ++cdeps;
3010 /* Add a symbol representing this version. */
3011 h = NULL;
3012 if (! (_bfd_generic_link_add_one_symbol
3013 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3014 (bfd_vma) 0, (const char *) NULL, false,
3015 get_elf_backend_data (dynobj)->collect,
3016 (struct bfd_link_hash_entry **) &h)))
3017 return false;
3018 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3019 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3020 h->type = STT_OBJECT;
3021 h->verinfo.vertree = t;
3023 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3024 return false;
3026 def.vd_version = VER_DEF_CURRENT;
3027 def.vd_flags = 0;
3028 if (t->globals == NULL && t->locals == NULL && ! t->used)
3029 def.vd_flags |= VER_FLG_WEAK;
3030 def.vd_ndx = t->vernum + 1;
3031 def.vd_cnt = cdeps + 1;
3032 def.vd_hash = bfd_elf_hash (t->name);
3033 def.vd_aux = sizeof (Elf_External_Verdef);
3034 if (t->next != NULL)
3035 def.vd_next = (sizeof (Elf_External_Verdef)
3036 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3037 else
3038 def.vd_next = 0;
3040 _bfd_elf_swap_verdef_out (output_bfd, &def,
3041 (Elf_External_Verdef *) p);
3042 p += sizeof (Elf_External_Verdef);
3044 defaux.vda_name = h->dynstr_index;
3045 if (t->deps == NULL)
3046 defaux.vda_next = 0;
3047 else
3048 defaux.vda_next = sizeof (Elf_External_Verdaux);
3049 t->name_indx = defaux.vda_name;
3051 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3052 (Elf_External_Verdaux *) p);
3053 p += sizeof (Elf_External_Verdaux);
3055 for (n = t->deps; n != NULL; n = n->next)
3057 if (n->version_needed == NULL)
3059 /* This can happen if there was an error in the
3060 version script. */
3061 defaux.vda_name = 0;
3063 else
3064 defaux.vda_name = n->version_needed->name_indx;
3065 if (n->next == NULL)
3066 defaux.vda_next = 0;
3067 else
3068 defaux.vda_next = sizeof (Elf_External_Verdaux);
3070 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3071 (Elf_External_Verdaux *) p);
3072 p += sizeof (Elf_External_Verdaux);
3076 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3077 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3078 return false;
3080 elf_tdata (output_bfd)->cverdefs = cdefs;
3083 /* Work out the size of the version reference section. */
3085 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3086 BFD_ASSERT (s != NULL);
3088 struct elf_find_verdep_info sinfo;
3090 sinfo.output_bfd = output_bfd;
3091 sinfo.info = info;
3092 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3093 if (sinfo.vers == 0)
3094 sinfo.vers = 1;
3095 sinfo.failed = false;
3097 elf_link_hash_traverse (elf_hash_table (info),
3098 elf_link_find_version_dependencies,
3099 (PTR) &sinfo);
3101 if (elf_tdata (output_bfd)->verref == NULL)
3102 _bfd_strip_section_from_output (info, s);
3103 else
3105 Elf_Internal_Verneed *t;
3106 unsigned int size;
3107 unsigned int crefs;
3108 bfd_byte *p;
3110 /* Build the version definition section. */
3111 size = 0;
3112 crefs = 0;
3113 for (t = elf_tdata (output_bfd)->verref;
3114 t != NULL;
3115 t = t->vn_nextref)
3117 Elf_Internal_Vernaux *a;
3119 size += sizeof (Elf_External_Verneed);
3120 ++crefs;
3121 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3122 size += sizeof (Elf_External_Vernaux);
3125 s->_raw_size = size;
3126 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3127 if (s->contents == NULL)
3128 return false;
3130 p = s->contents;
3131 for (t = elf_tdata (output_bfd)->verref;
3132 t != NULL;
3133 t = t->vn_nextref)
3135 unsigned int caux;
3136 Elf_Internal_Vernaux *a;
3137 bfd_size_type indx;
3139 caux = 0;
3140 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3141 ++caux;
3143 t->vn_version = VER_NEED_CURRENT;
3144 t->vn_cnt = caux;
3145 if (elf_dt_name (t->vn_bfd) != NULL)
3146 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3147 elf_dt_name (t->vn_bfd),
3148 true, false);
3149 else
3150 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3151 t->vn_bfd->filename, true, false);
3152 if (indx == (bfd_size_type) -1)
3153 return false;
3154 t->vn_file = indx;
3155 t->vn_aux = sizeof (Elf_External_Verneed);
3156 if (t->vn_nextref == NULL)
3157 t->vn_next = 0;
3158 else
3159 t->vn_next = (sizeof (Elf_External_Verneed)
3160 + caux * sizeof (Elf_External_Vernaux));
3162 _bfd_elf_swap_verneed_out (output_bfd, t,
3163 (Elf_External_Verneed *) p);
3164 p += sizeof (Elf_External_Verneed);
3166 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3168 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3169 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3170 a->vna_nodename, true, false);
3171 if (indx == (bfd_size_type) -1)
3172 return false;
3173 a->vna_name = indx;
3174 if (a->vna_nextptr == NULL)
3175 a->vna_next = 0;
3176 else
3177 a->vna_next = sizeof (Elf_External_Vernaux);
3179 _bfd_elf_swap_vernaux_out (output_bfd, a,
3180 (Elf_External_Vernaux *) p);
3181 p += sizeof (Elf_External_Vernaux);
3185 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3186 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3187 return false;
3189 elf_tdata (output_bfd)->cverrefs = crefs;
3193 /* Assign dynsym indicies. In a shared library we generate a
3194 section symbol for each output section, which come first.
3195 Next come all of the back-end allocated local dynamic syms,
3196 followed by the rest of the global symbols. */
3198 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3200 /* Work out the size of the symbol version section. */
3201 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3202 BFD_ASSERT (s != NULL);
3203 if (dynsymcount == 0
3204 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3206 _bfd_strip_section_from_output (info, s);
3207 /* The DYNSYMCOUNT might have changed if we were going to
3208 output a dynamic symbol table entry for S. */
3209 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3211 else
3213 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3214 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3215 if (s->contents == NULL)
3216 return false;
3218 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3219 return false;
3222 /* Set the size of the .dynsym and .hash sections. We counted
3223 the number of dynamic symbols in elf_link_add_object_symbols.
3224 We will build the contents of .dynsym and .hash when we build
3225 the final symbol table, because until then we do not know the
3226 correct value to give the symbols. We built the .dynstr
3227 section as we went along in elf_link_add_object_symbols. */
3228 s = bfd_get_section_by_name (dynobj, ".dynsym");
3229 BFD_ASSERT (s != NULL);
3230 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3231 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3232 if (s->contents == NULL && s->_raw_size != 0)
3233 return false;
3235 /* The first entry in .dynsym is a dummy symbol. */
3236 isym.st_value = 0;
3237 isym.st_size = 0;
3238 isym.st_name = 0;
3239 isym.st_info = 0;
3240 isym.st_other = 0;
3241 isym.st_shndx = 0;
3242 elf_swap_symbol_out (output_bfd, &isym,
3243 (PTR) (Elf_External_Sym *) s->contents);
3245 /* Compute the size of the hashing table. As a side effect this
3246 computes the hash values for all the names we export. */
3247 bucketcount = compute_bucket_count (info);
3249 s = bfd_get_section_by_name (dynobj, ".hash");
3250 BFD_ASSERT (s != NULL);
3251 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3252 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3253 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3254 if (s->contents == NULL)
3255 return false;
3256 memset (s->contents, 0, (size_t) s->_raw_size);
3258 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3259 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3260 s->contents + hash_entry_size);
3262 elf_hash_table (info)->bucketcount = bucketcount;
3264 s = bfd_get_section_by_name (dynobj, ".dynstr");
3265 BFD_ASSERT (s != NULL);
3266 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3268 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3269 return false;
3272 return true;
3275 /* Fix up the flags for a symbol. This handles various cases which
3276 can only be fixed after all the input files are seen. This is
3277 currently called by both adjust_dynamic_symbol and
3278 assign_sym_version, which is unnecessary but perhaps more robust in
3279 the face of future changes. */
3281 static boolean
3282 elf_fix_symbol_flags (h, eif)
3283 struct elf_link_hash_entry *h;
3284 struct elf_info_failed *eif;
3286 /* If this symbol was mentioned in a non-ELF file, try to set
3287 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3288 permit a non-ELF file to correctly refer to a symbol defined in
3289 an ELF dynamic object. */
3290 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3292 while (h->root.type == bfd_link_hash_indirect)
3293 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3295 if (h->root.type != bfd_link_hash_defined
3296 && h->root.type != bfd_link_hash_defweak)
3297 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3298 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3299 else
3301 if (h->root.u.def.section->owner != NULL
3302 && (bfd_get_flavour (h->root.u.def.section->owner)
3303 == bfd_target_elf_flavour))
3304 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3305 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3306 else
3307 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3310 if (h->dynindx == -1
3311 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3312 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3314 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3316 eif->failed = true;
3317 return false;
3321 else
3323 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3324 was first seen in a non-ELF file. Fortunately, if the symbol
3325 was first seen in an ELF file, we're probably OK unless the
3326 symbol was defined in a non-ELF file. Catch that case here.
3327 FIXME: We're still in trouble if the symbol was first seen in
3328 a dynamic object, and then later in a non-ELF regular object. */
3329 if ((h->root.type == bfd_link_hash_defined
3330 || h->root.type == bfd_link_hash_defweak)
3331 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3332 && (h->root.u.def.section->owner != NULL
3333 ? (bfd_get_flavour (h->root.u.def.section->owner)
3334 != bfd_target_elf_flavour)
3335 : (bfd_is_abs_section (h->root.u.def.section)
3336 && (h->elf_link_hash_flags
3337 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3338 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3341 /* If this is a final link, and the symbol was defined as a common
3342 symbol in a regular object file, and there was no definition in
3343 any dynamic object, then the linker will have allocated space for
3344 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3345 flag will not have been set. */
3346 if (h->root.type == bfd_link_hash_defined
3347 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3348 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3349 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3350 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3351 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3353 /* If -Bsymbolic was used (which means to bind references to global
3354 symbols to the definition within the shared object), and this
3355 symbol was defined in a regular object, then it actually doesn't
3356 need a PLT entry. Likewise, if the symbol has any kind of
3357 visibility (internal, hidden, or protected), it doesn't need a
3358 PLT. */
3359 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3360 && eif->info->shared
3361 && (eif->info->symbolic || ELF_ST_VISIBILITY (h->other))
3362 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3364 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3365 h->plt.offset = (bfd_vma) -1;
3368 /* If this is a weak defined symbol in a dynamic object, and we know
3369 the real definition in the dynamic object, copy interesting flags
3370 over to the real definition. */
3371 if (h->weakdef != NULL)
3373 struct elf_link_hash_entry *weakdef;
3375 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3376 || h->root.type == bfd_link_hash_defweak);
3377 weakdef = h->weakdef;
3378 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3379 || weakdef->root.type == bfd_link_hash_defweak);
3380 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3382 /* If the real definition is defined by a regular object file,
3383 don't do anything special. See the longer description in
3384 elf_adjust_dynamic_symbol, below. */
3385 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3386 h->weakdef = NULL;
3387 else
3388 weakdef->elf_link_hash_flags |=
3389 (h->elf_link_hash_flags
3390 & (ELF_LINK_HASH_REF_REGULAR
3391 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3392 | ELF_LINK_NON_GOT_REF));
3395 return true;
3398 /* Make the backend pick a good value for a dynamic symbol. This is
3399 called via elf_link_hash_traverse, and also calls itself
3400 recursively. */
3402 static boolean
3403 elf_adjust_dynamic_symbol (h, data)
3404 struct elf_link_hash_entry *h;
3405 PTR data;
3407 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3408 bfd *dynobj;
3409 struct elf_backend_data *bed;
3411 /* Ignore indirect symbols. These are added by the versioning code. */
3412 if (h->root.type == bfd_link_hash_indirect)
3413 return true;
3415 /* Fix the symbol flags. */
3416 if (! elf_fix_symbol_flags (h, eif))
3417 return false;
3419 /* If this symbol does not require a PLT entry, and it is not
3420 defined by a dynamic object, or is not referenced by a regular
3421 object, ignore it. We do have to handle a weak defined symbol,
3422 even if no regular object refers to it, if we decided to add it
3423 to the dynamic symbol table. FIXME: Do we normally need to worry
3424 about symbols which are defined by one dynamic object and
3425 referenced by another one? */
3426 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3427 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3428 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3429 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3430 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3432 h->plt.offset = (bfd_vma) -1;
3433 return true;
3436 /* If we've already adjusted this symbol, don't do it again. This
3437 can happen via a recursive call. */
3438 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3439 return true;
3441 /* Don't look at this symbol again. Note that we must set this
3442 after checking the above conditions, because we may look at a
3443 symbol once, decide not to do anything, and then get called
3444 recursively later after REF_REGULAR is set below. */
3445 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3447 /* If this is a weak definition, and we know a real definition, and
3448 the real symbol is not itself defined by a regular object file,
3449 then get a good value for the real definition. We handle the
3450 real symbol first, for the convenience of the backend routine.
3452 Note that there is a confusing case here. If the real definition
3453 is defined by a regular object file, we don't get the real symbol
3454 from the dynamic object, but we do get the weak symbol. If the
3455 processor backend uses a COPY reloc, then if some routine in the
3456 dynamic object changes the real symbol, we will not see that
3457 change in the corresponding weak symbol. This is the way other
3458 ELF linkers work as well, and seems to be a result of the shared
3459 library model.
3461 I will clarify this issue. Most SVR4 shared libraries define the
3462 variable _timezone and define timezone as a weak synonym. The
3463 tzset call changes _timezone. If you write
3464 extern int timezone;
3465 int _timezone = 5;
3466 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3467 you might expect that, since timezone is a synonym for _timezone,
3468 the same number will print both times. However, if the processor
3469 backend uses a COPY reloc, then actually timezone will be copied
3470 into your process image, and, since you define _timezone
3471 yourself, _timezone will not. Thus timezone and _timezone will
3472 wind up at different memory locations. The tzset call will set
3473 _timezone, leaving timezone unchanged. */
3475 if (h->weakdef != NULL)
3477 /* If we get to this point, we know there is an implicit
3478 reference by a regular object file via the weak symbol H.
3479 FIXME: Is this really true? What if the traversal finds
3480 H->WEAKDEF before it finds H? */
3481 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3483 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3484 return false;
3487 /* If a symbol has no type and no size and does not require a PLT
3488 entry, then we are probably about to do the wrong thing here: we
3489 are probably going to create a COPY reloc for an empty object.
3490 This case can arise when a shared object is built with assembly
3491 code, and the assembly code fails to set the symbol type. */
3492 if (h->size == 0
3493 && h->type == STT_NOTYPE
3494 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3495 (*_bfd_error_handler)
3496 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3497 h->root.root.string);
3499 dynobj = elf_hash_table (eif->info)->dynobj;
3500 bed = get_elf_backend_data (dynobj);
3501 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3503 eif->failed = true;
3504 return false;
3507 return true;
3510 /* This routine is used to export all defined symbols into the dynamic
3511 symbol table. It is called via elf_link_hash_traverse. */
3513 static boolean
3514 elf_export_symbol (h, data)
3515 struct elf_link_hash_entry *h;
3516 PTR data;
3518 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3520 /* Ignore indirect symbols. These are added by the versioning code. */
3521 if (h->root.type == bfd_link_hash_indirect)
3522 return true;
3524 if (h->dynindx == -1
3525 && (h->elf_link_hash_flags
3526 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3528 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3530 eif->failed = true;
3531 return false;
3535 return true;
3538 /* Look through the symbols which are defined in other shared
3539 libraries and referenced here. Update the list of version
3540 dependencies. This will be put into the .gnu.version_r section.
3541 This function is called via elf_link_hash_traverse. */
3543 static boolean
3544 elf_link_find_version_dependencies (h, data)
3545 struct elf_link_hash_entry *h;
3546 PTR data;
3548 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3549 Elf_Internal_Verneed *t;
3550 Elf_Internal_Vernaux *a;
3552 /* We only care about symbols defined in shared objects with version
3553 information. */
3554 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3555 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3556 || h->dynindx == -1
3557 || h->verinfo.verdef == NULL)
3558 return true;
3560 /* See if we already know about this version. */
3561 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3563 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3564 continue;
3566 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3567 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3568 return true;
3570 break;
3573 /* This is a new version. Add it to tree we are building. */
3575 if (t == NULL)
3577 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3578 if (t == NULL)
3580 rinfo->failed = true;
3581 return false;
3584 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3585 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3586 elf_tdata (rinfo->output_bfd)->verref = t;
3589 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3591 /* Note that we are copying a string pointer here, and testing it
3592 above. If bfd_elf_string_from_elf_section is ever changed to
3593 discard the string data when low in memory, this will have to be
3594 fixed. */
3595 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3597 a->vna_flags = h->verinfo.verdef->vd_flags;
3598 a->vna_nextptr = t->vn_auxptr;
3600 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3601 ++rinfo->vers;
3603 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3605 t->vn_auxptr = a;
3607 return true;
3610 /* Figure out appropriate versions for all the symbols. We may not
3611 have the version number script until we have read all of the input
3612 files, so until that point we don't know which symbols should be
3613 local. This function is called via elf_link_hash_traverse. */
3615 static boolean
3616 elf_link_assign_sym_version (h, data)
3617 struct elf_link_hash_entry *h;
3618 PTR data;
3620 struct elf_assign_sym_version_info *sinfo =
3621 (struct elf_assign_sym_version_info *) data;
3622 struct bfd_link_info *info = sinfo->info;
3623 struct elf_backend_data *bed;
3624 struct elf_info_failed eif;
3625 char *p;
3627 /* Fix the symbol flags. */
3628 eif.failed = false;
3629 eif.info = info;
3630 if (! elf_fix_symbol_flags (h, &eif))
3632 if (eif.failed)
3633 sinfo->failed = true;
3634 return false;
3637 /* We only need version numbers for symbols defined in regular
3638 objects. */
3639 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3640 return true;
3642 bed = get_elf_backend_data (sinfo->output_bfd);
3643 p = strchr (h->root.root.string, ELF_VER_CHR);
3644 if (p != NULL && h->verinfo.vertree == NULL)
3646 struct bfd_elf_version_tree *t;
3647 boolean hidden;
3649 hidden = true;
3651 /* There are two consecutive ELF_VER_CHR characters if this is
3652 not a hidden symbol. */
3653 ++p;
3654 if (*p == ELF_VER_CHR)
3656 hidden = false;
3657 ++p;
3660 /* If there is no version string, we can just return out. */
3661 if (*p == '\0')
3663 if (hidden)
3664 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3665 return true;
3668 /* Look for the version. If we find it, it is no longer weak. */
3669 for (t = sinfo->verdefs; t != NULL; t = t->next)
3671 if (strcmp (t->name, p) == 0)
3673 int len;
3674 char *alc;
3675 struct bfd_elf_version_expr *d;
3677 len = p - h->root.root.string;
3678 alc = bfd_alloc (sinfo->output_bfd, len);
3679 if (alc == NULL)
3680 return false;
3681 strncpy (alc, h->root.root.string, len - 1);
3682 alc[len - 1] = '\0';
3683 if (alc[len - 2] == ELF_VER_CHR)
3684 alc[len - 2] = '\0';
3686 h->verinfo.vertree = t;
3687 t->used = true;
3688 d = NULL;
3690 if (t->globals != NULL)
3692 for (d = t->globals; d != NULL; d = d->next)
3693 if ((*d->match) (d, alc))
3694 break;
3697 /* See if there is anything to force this symbol to
3698 local scope. */
3699 if (d == NULL && t->locals != NULL)
3701 for (d = t->locals; d != NULL; d = d->next)
3703 if ((*d->match) (d, alc))
3705 if (h->dynindx != -1
3706 && info->shared
3707 && ! sinfo->export_dynamic)
3709 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3710 (*bed->elf_backend_hide_symbol) (h);
3711 /* FIXME: The name of the symbol has
3712 already been recorded in the dynamic
3713 string table section. */
3716 break;
3721 bfd_release (sinfo->output_bfd, alc);
3722 break;
3726 /* If we are building an application, we need to create a
3727 version node for this version. */
3728 if (t == NULL && ! info->shared)
3730 struct bfd_elf_version_tree **pp;
3731 int version_index;
3733 /* If we aren't going to export this symbol, we don't need
3734 to worry about it. */
3735 if (h->dynindx == -1)
3736 return true;
3738 t = ((struct bfd_elf_version_tree *)
3739 bfd_alloc (sinfo->output_bfd, sizeof *t));
3740 if (t == NULL)
3742 sinfo->failed = true;
3743 return false;
3746 t->next = NULL;
3747 t->name = p;
3748 t->globals = NULL;
3749 t->locals = NULL;
3750 t->deps = NULL;
3751 t->name_indx = (unsigned int) -1;
3752 t->used = true;
3754 version_index = 1;
3755 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3756 ++version_index;
3757 t->vernum = version_index;
3759 *pp = t;
3761 h->verinfo.vertree = t;
3763 else if (t == NULL)
3765 /* We could not find the version for a symbol when
3766 generating a shared archive. Return an error. */
3767 (*_bfd_error_handler)
3768 (_("%s: undefined versioned symbol name %s"),
3769 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3770 bfd_set_error (bfd_error_bad_value);
3771 sinfo->failed = true;
3772 return false;
3775 if (hidden)
3776 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3779 /* If we don't have a version for this symbol, see if we can find
3780 something. */
3781 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3783 struct bfd_elf_version_tree *t;
3784 struct bfd_elf_version_tree *deflt;
3785 struct bfd_elf_version_expr *d;
3787 /* See if can find what version this symbol is in. If the
3788 symbol is supposed to be local, then don't actually register
3789 it. */
3790 deflt = NULL;
3791 for (t = sinfo->verdefs; t != NULL; t = t->next)
3793 if (t->globals != NULL)
3795 for (d = t->globals; d != NULL; d = d->next)
3797 if ((*d->match) (d, h->root.root.string))
3799 h->verinfo.vertree = t;
3800 break;
3804 if (d != NULL)
3805 break;
3808 if (t->locals != NULL)
3810 for (d = t->locals; d != NULL; d = d->next)
3812 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3813 deflt = t;
3814 else if ((*d->match) (d, h->root.root.string))
3816 h->verinfo.vertree = t;
3817 if (h->dynindx != -1
3818 && info->shared
3819 && ! sinfo->export_dynamic)
3821 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3822 (*bed->elf_backend_hide_symbol) (h);
3823 /* FIXME: The name of the symbol has already
3824 been recorded in the dynamic string table
3825 section. */
3827 break;
3831 if (d != NULL)
3832 break;
3836 if (deflt != NULL && h->verinfo.vertree == NULL)
3838 h->verinfo.vertree = deflt;
3839 if (h->dynindx != -1
3840 && info->shared
3841 && ! sinfo->export_dynamic)
3843 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3844 (*bed->elf_backend_hide_symbol) (h);
3845 /* FIXME: The name of the symbol has already been
3846 recorded in the dynamic string table section. */
3851 return true;
3854 /* Final phase of ELF linker. */
3856 /* A structure we use to avoid passing large numbers of arguments. */
3858 struct elf_final_link_info
3860 /* General link information. */
3861 struct bfd_link_info *info;
3862 /* Output BFD. */
3863 bfd *output_bfd;
3864 /* Symbol string table. */
3865 struct bfd_strtab_hash *symstrtab;
3866 /* .dynsym section. */
3867 asection *dynsym_sec;
3868 /* .hash section. */
3869 asection *hash_sec;
3870 /* symbol version section (.gnu.version). */
3871 asection *symver_sec;
3872 /* Buffer large enough to hold contents of any section. */
3873 bfd_byte *contents;
3874 /* Buffer large enough to hold external relocs of any section. */
3875 PTR external_relocs;
3876 /* Buffer large enough to hold internal relocs of any section. */
3877 Elf_Internal_Rela *internal_relocs;
3878 /* Buffer large enough to hold external local symbols of any input
3879 BFD. */
3880 Elf_External_Sym *external_syms;
3881 /* Buffer large enough to hold internal local symbols of any input
3882 BFD. */
3883 Elf_Internal_Sym *internal_syms;
3884 /* Array large enough to hold a symbol index for each local symbol
3885 of any input BFD. */
3886 long *indices;
3887 /* Array large enough to hold a section pointer for each local
3888 symbol of any input BFD. */
3889 asection **sections;
3890 /* Buffer to hold swapped out symbols. */
3891 Elf_External_Sym *symbuf;
3892 /* Number of swapped out symbols in buffer. */
3893 size_t symbuf_count;
3894 /* Number of symbols which fit in symbuf. */
3895 size_t symbuf_size;
3898 static boolean elf_link_output_sym
3899 PARAMS ((struct elf_final_link_info *, const char *,
3900 Elf_Internal_Sym *, asection *));
3901 static boolean elf_link_flush_output_syms
3902 PARAMS ((struct elf_final_link_info *));
3903 static boolean elf_link_output_extsym
3904 PARAMS ((struct elf_link_hash_entry *, PTR));
3905 static boolean elf_link_input_bfd
3906 PARAMS ((struct elf_final_link_info *, bfd *));
3907 static boolean elf_reloc_link_order
3908 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3909 struct bfd_link_order *));
3911 /* This struct is used to pass information to elf_link_output_extsym. */
3913 struct elf_outext_info
3915 boolean failed;
3916 boolean localsyms;
3917 struct elf_final_link_info *finfo;
3920 /* Compute the size of, and allocate space for, REL_HDR which is the
3921 section header for a section containing relocations for O. */
3923 static boolean
3924 elf_link_size_reloc_section (abfd, rel_hdr, o)
3925 bfd *abfd;
3926 Elf_Internal_Shdr *rel_hdr;
3927 asection *o;
3929 register struct elf_link_hash_entry **p, **pend;
3930 unsigned reloc_count;
3932 /* Figure out how many relocations there will be. */
3933 if (rel_hdr == &elf_section_data (o)->rel_hdr)
3934 reloc_count = elf_section_data (o)->rel_count;
3935 else
3936 reloc_count = elf_section_data (o)->rel_count2;
3938 /* That allows us to calculate the size of the section. */
3939 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
3941 /* The contents field must last into write_object_contents, so we
3942 allocate it with bfd_alloc rather than malloc. */
3943 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3944 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3945 return false;
3947 /* We only allocate one set of hash entries, so we only do it the
3948 first time we are called. */
3949 if (elf_section_data (o)->rel_hashes == NULL)
3951 p = ((struct elf_link_hash_entry **)
3952 bfd_malloc (o->reloc_count
3953 * sizeof (struct elf_link_hash_entry *)));
3954 if (p == NULL && o->reloc_count != 0)
3955 return false;
3957 elf_section_data (o)->rel_hashes = p;
3958 pend = p + o->reloc_count;
3959 for (; p < pend; p++)
3960 *p = NULL;
3963 return true;
3966 /* When performing a relocateable link, the input relocations are
3967 preserved. But, if they reference global symbols, the indices
3968 referenced must be updated. Update all the relocations in
3969 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
3971 static void
3972 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
3973 bfd *abfd;
3974 Elf_Internal_Shdr *rel_hdr;
3975 unsigned int count;
3976 struct elf_link_hash_entry **rel_hash;
3978 unsigned int i;
3980 for (i = 0; i < count; i++, rel_hash++)
3982 if (*rel_hash == NULL)
3983 continue;
3985 BFD_ASSERT ((*rel_hash)->indx >= 0);
3987 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3989 Elf_External_Rel *erel;
3990 Elf_Internal_Rel irel;
3992 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3993 elf_swap_reloc_in (abfd, erel, &irel);
3994 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3995 ELF_R_TYPE (irel.r_info));
3996 elf_swap_reloc_out (abfd, &irel, erel);
3998 else
4000 Elf_External_Rela *erela;
4001 Elf_Internal_Rela irela;
4003 BFD_ASSERT (rel_hdr->sh_entsize
4004 == sizeof (Elf_External_Rela));
4006 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4007 elf_swap_reloca_in (abfd, erela, &irela);
4008 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4009 ELF_R_TYPE (irela.r_info));
4010 elf_swap_reloca_out (abfd, &irela, erela);
4015 /* Do the final step of an ELF link. */
4017 boolean
4018 elf_bfd_final_link (abfd, info)
4019 bfd *abfd;
4020 struct bfd_link_info *info;
4022 boolean dynamic;
4023 bfd *dynobj;
4024 struct elf_final_link_info finfo;
4025 register asection *o;
4026 register struct bfd_link_order *p;
4027 register bfd *sub;
4028 size_t max_contents_size;
4029 size_t max_external_reloc_size;
4030 size_t max_internal_reloc_count;
4031 size_t max_sym_count;
4032 file_ptr off;
4033 Elf_Internal_Sym elfsym;
4034 unsigned int i;
4035 Elf_Internal_Shdr *symtab_hdr;
4036 Elf_Internal_Shdr *symstrtab_hdr;
4037 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4038 struct elf_outext_info eoinfo;
4040 if (info->shared)
4041 abfd->flags |= DYNAMIC;
4043 dynamic = elf_hash_table (info)->dynamic_sections_created;
4044 dynobj = elf_hash_table (info)->dynobj;
4046 finfo.info = info;
4047 finfo.output_bfd = abfd;
4048 finfo.symstrtab = elf_stringtab_init ();
4049 if (finfo.symstrtab == NULL)
4050 return false;
4052 if (! dynamic)
4054 finfo.dynsym_sec = NULL;
4055 finfo.hash_sec = NULL;
4056 finfo.symver_sec = NULL;
4058 else
4060 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4061 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4062 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4063 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4064 /* Note that it is OK if symver_sec is NULL. */
4067 finfo.contents = NULL;
4068 finfo.external_relocs = NULL;
4069 finfo.internal_relocs = NULL;
4070 finfo.external_syms = NULL;
4071 finfo.internal_syms = NULL;
4072 finfo.indices = NULL;
4073 finfo.sections = NULL;
4074 finfo.symbuf = NULL;
4075 finfo.symbuf_count = 0;
4077 /* Count up the number of relocations we will output for each output
4078 section, so that we know the sizes of the reloc sections. We
4079 also figure out some maximum sizes. */
4080 max_contents_size = 0;
4081 max_external_reloc_size = 0;
4082 max_internal_reloc_count = 0;
4083 max_sym_count = 0;
4084 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4086 o->reloc_count = 0;
4088 for (p = o->link_order_head; p != NULL; p = p->next)
4090 if (p->type == bfd_section_reloc_link_order
4091 || p->type == bfd_symbol_reloc_link_order)
4092 ++o->reloc_count;
4093 else if (p->type == bfd_indirect_link_order)
4095 asection *sec;
4097 sec = p->u.indirect.section;
4099 /* Mark all sections which are to be included in the
4100 link. This will normally be every section. We need
4101 to do this so that we can identify any sections which
4102 the linker has decided to not include. */
4103 sec->linker_mark = true;
4105 if (info->relocateable || info->emitrelocations)
4106 o->reloc_count += sec->reloc_count;
4108 if (sec->_raw_size > max_contents_size)
4109 max_contents_size = sec->_raw_size;
4110 if (sec->_cooked_size > max_contents_size)
4111 max_contents_size = sec->_cooked_size;
4113 /* We are interested in just local symbols, not all
4114 symbols. */
4115 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4116 && (sec->owner->flags & DYNAMIC) == 0)
4118 size_t sym_count;
4120 if (elf_bad_symtab (sec->owner))
4121 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4122 / sizeof (Elf_External_Sym));
4123 else
4124 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4126 if (sym_count > max_sym_count)
4127 max_sym_count = sym_count;
4129 if ((sec->flags & SEC_RELOC) != 0)
4131 size_t ext_size;
4133 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4134 if (ext_size > max_external_reloc_size)
4135 max_external_reloc_size = ext_size;
4136 if (sec->reloc_count > max_internal_reloc_count)
4137 max_internal_reloc_count = sec->reloc_count;
4143 if (o->reloc_count > 0)
4144 o->flags |= SEC_RELOC;
4145 else
4147 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4148 set it (this is probably a bug) and if it is set
4149 assign_section_numbers will create a reloc section. */
4150 o->flags &=~ SEC_RELOC;
4153 /* If the SEC_ALLOC flag is not set, force the section VMA to
4154 zero. This is done in elf_fake_sections as well, but forcing
4155 the VMA to 0 here will ensure that relocs against these
4156 sections are handled correctly. */
4157 if ((o->flags & SEC_ALLOC) == 0
4158 && ! o->user_set_vma)
4159 o->vma = 0;
4162 /* Figure out the file positions for everything but the symbol table
4163 and the relocs. We set symcount to force assign_section_numbers
4164 to create a symbol table. */
4165 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4166 BFD_ASSERT (! abfd->output_has_begun);
4167 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4168 goto error_return;
4170 /* Figure out how many relocations we will have in each section.
4171 Just using RELOC_COUNT isn't good enough since that doesn't
4172 maintain a separate value for REL vs. RELA relocations. */
4173 if (info->relocateable || info->emitrelocations)
4174 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4175 for (o = sub->sections; o != NULL; o = o->next)
4177 asection *output_section;
4179 if (! o->linker_mark)
4181 /* This section was omitted from the link. */
4182 continue;
4185 output_section = o->output_section;
4187 if (output_section != NULL
4188 && (o->flags & SEC_RELOC) != 0)
4190 struct bfd_elf_section_data *esdi
4191 = elf_section_data (o);
4192 struct bfd_elf_section_data *esdo
4193 = elf_section_data (output_section);
4194 unsigned int *rel_count;
4195 unsigned int *rel_count2;
4197 /* We must be careful to add the relocation froms the
4198 input section to the right output count. */
4199 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4201 rel_count = &esdo->rel_count;
4202 rel_count2 = &esdo->rel_count2;
4204 else
4206 rel_count = &esdo->rel_count2;
4207 rel_count2 = &esdo->rel_count;
4210 *rel_count += (esdi->rel_hdr.sh_size
4211 / esdi->rel_hdr.sh_entsize);
4212 if (esdi->rel_hdr2)
4213 *rel_count2 += (esdi->rel_hdr2->sh_size
4214 / esdi->rel_hdr2->sh_entsize);
4218 /* That created the reloc sections. Set their sizes, and assign
4219 them file positions, and allocate some buffers. */
4220 for (o = abfd->sections; o != NULL; o = o->next)
4222 if ((o->flags & SEC_RELOC) != 0)
4224 if (!elf_link_size_reloc_section (abfd,
4225 &elf_section_data (o)->rel_hdr,
4227 goto error_return;
4229 if (elf_section_data (o)->rel_hdr2
4230 && !elf_link_size_reloc_section (abfd,
4231 elf_section_data (o)->rel_hdr2,
4233 goto error_return;
4236 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4237 to count upwards while actually outputting the relocations. */
4238 elf_section_data (o)->rel_count = 0;
4239 elf_section_data (o)->rel_count2 = 0;
4242 _bfd_elf_assign_file_positions_for_relocs (abfd);
4244 /* We have now assigned file positions for all the sections except
4245 .symtab and .strtab. We start the .symtab section at the current
4246 file position, and write directly to it. We build the .strtab
4247 section in memory. */
4248 bfd_get_symcount (abfd) = 0;
4249 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4250 /* sh_name is set in prep_headers. */
4251 symtab_hdr->sh_type = SHT_SYMTAB;
4252 symtab_hdr->sh_flags = 0;
4253 symtab_hdr->sh_addr = 0;
4254 symtab_hdr->sh_size = 0;
4255 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4256 /* sh_link is set in assign_section_numbers. */
4257 /* sh_info is set below. */
4258 /* sh_offset is set just below. */
4259 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4261 off = elf_tdata (abfd)->next_file_pos;
4262 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4264 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4265 incorrect. We do not yet know the size of the .symtab section.
4266 We correct next_file_pos below, after we do know the size. */
4268 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4269 continuously seeking to the right position in the file. */
4270 if (! info->keep_memory || max_sym_count < 20)
4271 finfo.symbuf_size = 20;
4272 else
4273 finfo.symbuf_size = max_sym_count;
4274 finfo.symbuf = ((Elf_External_Sym *)
4275 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4276 if (finfo.symbuf == NULL)
4277 goto error_return;
4279 /* Start writing out the symbol table. The first symbol is always a
4280 dummy symbol. */
4281 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4283 elfsym.st_value = 0;
4284 elfsym.st_size = 0;
4285 elfsym.st_info = 0;
4286 elfsym.st_other = 0;
4287 elfsym.st_shndx = SHN_UNDEF;
4288 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4289 &elfsym, bfd_und_section_ptr))
4290 goto error_return;
4293 #if 0
4294 /* Some standard ELF linkers do this, but we don't because it causes
4295 bootstrap comparison failures. */
4296 /* Output a file symbol for the output file as the second symbol.
4297 We output this even if we are discarding local symbols, although
4298 I'm not sure if this is correct. */
4299 elfsym.st_value = 0;
4300 elfsym.st_size = 0;
4301 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4302 elfsym.st_other = 0;
4303 elfsym.st_shndx = SHN_ABS;
4304 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4305 &elfsym, bfd_abs_section_ptr))
4306 goto error_return;
4307 #endif
4309 /* Output a symbol for each section. We output these even if we are
4310 discarding local symbols, since they are used for relocs. These
4311 symbols have no names. We store the index of each one in the
4312 index field of the section, so that we can find it again when
4313 outputting relocs. */
4314 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4316 elfsym.st_size = 0;
4317 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4318 elfsym.st_other = 0;
4319 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4321 o = section_from_elf_index (abfd, i);
4322 if (o != NULL)
4323 o->target_index = bfd_get_symcount (abfd);
4324 elfsym.st_shndx = i;
4325 if (info->relocateable || o == NULL)
4326 elfsym.st_value = 0;
4327 else
4328 elfsym.st_value = o->vma;
4329 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4330 &elfsym, o))
4331 goto error_return;
4335 /* Allocate some memory to hold information read in from the input
4336 files. */
4337 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4338 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4339 finfo.internal_relocs = ((Elf_Internal_Rela *)
4340 bfd_malloc (max_internal_reloc_count
4341 * sizeof (Elf_Internal_Rela)
4342 * bed->s->int_rels_per_ext_rel));
4343 finfo.external_syms = ((Elf_External_Sym *)
4344 bfd_malloc (max_sym_count
4345 * sizeof (Elf_External_Sym)));
4346 finfo.internal_syms = ((Elf_Internal_Sym *)
4347 bfd_malloc (max_sym_count
4348 * sizeof (Elf_Internal_Sym)));
4349 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4350 finfo.sections = ((asection **)
4351 bfd_malloc (max_sym_count * sizeof (asection *)));
4352 if ((finfo.contents == NULL && max_contents_size != 0)
4353 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4354 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4355 || (finfo.external_syms == NULL && max_sym_count != 0)
4356 || (finfo.internal_syms == NULL && max_sym_count != 0)
4357 || (finfo.indices == NULL && max_sym_count != 0)
4358 || (finfo.sections == NULL && max_sym_count != 0))
4359 goto error_return;
4361 /* Since ELF permits relocations to be against local symbols, we
4362 must have the local symbols available when we do the relocations.
4363 Since we would rather only read the local symbols once, and we
4364 would rather not keep them in memory, we handle all the
4365 relocations for a single input file at the same time.
4367 Unfortunately, there is no way to know the total number of local
4368 symbols until we have seen all of them, and the local symbol
4369 indices precede the global symbol indices. This means that when
4370 we are generating relocateable output, and we see a reloc against
4371 a global symbol, we can not know the symbol index until we have
4372 finished examining all the local symbols to see which ones we are
4373 going to output. To deal with this, we keep the relocations in
4374 memory, and don't output them until the end of the link. This is
4375 an unfortunate waste of memory, but I don't see a good way around
4376 it. Fortunately, it only happens when performing a relocateable
4377 link, which is not the common case. FIXME: If keep_memory is set
4378 we could write the relocs out and then read them again; I don't
4379 know how bad the memory loss will be. */
4381 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4382 sub->output_has_begun = false;
4383 for (o = abfd->sections; o != NULL; o = o->next)
4385 for (p = o->link_order_head; p != NULL; p = p->next)
4387 if (p->type == bfd_indirect_link_order
4388 && (bfd_get_flavour (p->u.indirect.section->owner)
4389 == bfd_target_elf_flavour))
4391 sub = p->u.indirect.section->owner;
4392 if (! sub->output_has_begun)
4394 if (! elf_link_input_bfd (&finfo, sub))
4395 goto error_return;
4396 sub->output_has_begun = true;
4399 else if (p->type == bfd_section_reloc_link_order
4400 || p->type == bfd_symbol_reloc_link_order)
4402 if (! elf_reloc_link_order (abfd, info, o, p))
4403 goto error_return;
4405 else
4407 if (! _bfd_default_link_order (abfd, info, o, p))
4408 goto error_return;
4413 /* That wrote out all the local symbols. Finish up the symbol table
4414 with the global symbols. Even if we want to strip everything we
4415 can, we still need to deal with those global symbols that got
4416 converted to local in a version script. */
4418 if (info->shared)
4420 /* Output any global symbols that got converted to local in a
4421 version script. We do this in a separate step since ELF
4422 requires all local symbols to appear prior to any global
4423 symbols. FIXME: We should only do this if some global
4424 symbols were, in fact, converted to become local. FIXME:
4425 Will this work correctly with the Irix 5 linker? */
4426 eoinfo.failed = false;
4427 eoinfo.finfo = &finfo;
4428 eoinfo.localsyms = true;
4429 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4430 (PTR) &eoinfo);
4431 if (eoinfo.failed)
4432 return false;
4435 /* The sh_info field records the index of the first non local symbol. */
4436 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4438 if (dynamic)
4440 Elf_Internal_Sym sym;
4441 Elf_External_Sym *dynsym =
4442 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4443 long last_local = 0;
4445 /* Write out the section symbols for the output sections. */
4446 if (info->shared)
4448 asection *s;
4450 sym.st_size = 0;
4451 sym.st_name = 0;
4452 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4453 sym.st_other = 0;
4455 for (s = abfd->sections; s != NULL; s = s->next)
4457 int indx;
4458 indx = elf_section_data (s)->this_idx;
4459 BFD_ASSERT (indx > 0);
4460 sym.st_shndx = indx;
4461 sym.st_value = s->vma;
4463 elf_swap_symbol_out (abfd, &sym,
4464 dynsym + elf_section_data (s)->dynindx);
4467 last_local = bfd_count_sections (abfd);
4470 /* Write out the local dynsyms. */
4471 if (elf_hash_table (info)->dynlocal)
4473 struct elf_link_local_dynamic_entry *e;
4474 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4476 asection *s;
4478 sym.st_size = e->isym.st_size;
4479 sym.st_other = e->isym.st_other;
4481 /* Copy the internal symbol as is.
4482 Note that we saved a word of storage and overwrote
4483 the original st_name with the dynstr_index. */
4484 sym = e->isym;
4486 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4488 s = bfd_section_from_elf_index (e->input_bfd,
4489 e->isym.st_shndx);
4491 sym.st_shndx =
4492 elf_section_data (s->output_section)->this_idx;
4493 sym.st_value = (s->output_section->vma
4494 + s->output_offset
4495 + e->isym.st_value);
4498 if (last_local < e->dynindx)
4499 last_local = e->dynindx;
4501 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4505 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4506 last_local + 1;
4509 /* We get the global symbols from the hash table. */
4510 eoinfo.failed = false;
4511 eoinfo.localsyms = false;
4512 eoinfo.finfo = &finfo;
4513 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4514 (PTR) &eoinfo);
4515 if (eoinfo.failed)
4516 return false;
4518 /* If backend needs to output some symbols not present in the hash
4519 table, do it now. */
4520 if (bed->elf_backend_output_arch_syms)
4522 if (! (*bed->elf_backend_output_arch_syms)
4523 (abfd, info, (PTR) &finfo,
4524 (boolean (*) PARAMS ((PTR, const char *,
4525 Elf_Internal_Sym *, asection *)))
4526 elf_link_output_sym))
4527 return false;
4530 /* Flush all symbols to the file. */
4531 if (! elf_link_flush_output_syms (&finfo))
4532 return false;
4534 /* Now we know the size of the symtab section. */
4535 off += symtab_hdr->sh_size;
4537 /* Finish up and write out the symbol string table (.strtab)
4538 section. */
4539 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4540 /* sh_name was set in prep_headers. */
4541 symstrtab_hdr->sh_type = SHT_STRTAB;
4542 symstrtab_hdr->sh_flags = 0;
4543 symstrtab_hdr->sh_addr = 0;
4544 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4545 symstrtab_hdr->sh_entsize = 0;
4546 symstrtab_hdr->sh_link = 0;
4547 symstrtab_hdr->sh_info = 0;
4548 /* sh_offset is set just below. */
4549 symstrtab_hdr->sh_addralign = 1;
4551 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4552 elf_tdata (abfd)->next_file_pos = off;
4554 if (bfd_get_symcount (abfd) > 0)
4556 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4557 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4558 return false;
4561 /* Adjust the relocs to have the correct symbol indices. */
4562 for (o = abfd->sections; o != NULL; o = o->next)
4564 if ((o->flags & SEC_RELOC) == 0)
4565 continue;
4567 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4568 elf_section_data (o)->rel_count,
4569 elf_section_data (o)->rel_hashes);
4570 if (elf_section_data (o)->rel_hdr2 != NULL)
4571 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4572 elf_section_data (o)->rel_count2,
4573 (elf_section_data (o)->rel_hashes
4574 + elf_section_data (o)->rel_count));
4576 /* Set the reloc_count field to 0 to prevent write_relocs from
4577 trying to swap the relocs out itself. */
4578 o->reloc_count = 0;
4581 /* If we are linking against a dynamic object, or generating a
4582 shared library, finish up the dynamic linking information. */
4583 if (dynamic)
4585 Elf_External_Dyn *dyncon, *dynconend;
4587 /* Fix up .dynamic entries. */
4588 o = bfd_get_section_by_name (dynobj, ".dynamic");
4589 BFD_ASSERT (o != NULL);
4591 dyncon = (Elf_External_Dyn *) o->contents;
4592 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4593 for (; dyncon < dynconend; dyncon++)
4595 Elf_Internal_Dyn dyn;
4596 const char *name;
4597 unsigned int type;
4599 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4601 switch (dyn.d_tag)
4603 default:
4604 break;
4605 case DT_INIT:
4606 name = info->init_function;
4607 goto get_sym;
4608 case DT_FINI:
4609 name = info->fini_function;
4610 get_sym:
4612 struct elf_link_hash_entry *h;
4614 h = elf_link_hash_lookup (elf_hash_table (info), name,
4615 false, false, true);
4616 if (h != NULL
4617 && (h->root.type == bfd_link_hash_defined
4618 || h->root.type == bfd_link_hash_defweak))
4620 dyn.d_un.d_val = h->root.u.def.value;
4621 o = h->root.u.def.section;
4622 if (o->output_section != NULL)
4623 dyn.d_un.d_val += (o->output_section->vma
4624 + o->output_offset);
4625 else
4627 /* The symbol is imported from another shared
4628 library and does not apply to this one. */
4629 dyn.d_un.d_val = 0;
4632 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4635 break;
4637 case DT_HASH:
4638 name = ".hash";
4639 goto get_vma;
4640 case DT_STRTAB:
4641 name = ".dynstr";
4642 goto get_vma;
4643 case DT_SYMTAB:
4644 name = ".dynsym";
4645 goto get_vma;
4646 case DT_VERDEF:
4647 name = ".gnu.version_d";
4648 goto get_vma;
4649 case DT_VERNEED:
4650 name = ".gnu.version_r";
4651 goto get_vma;
4652 case DT_VERSYM:
4653 name = ".gnu.version";
4654 get_vma:
4655 o = bfd_get_section_by_name (abfd, name);
4656 BFD_ASSERT (o != NULL);
4657 dyn.d_un.d_ptr = o->vma;
4658 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4659 break;
4661 case DT_REL:
4662 case DT_RELA:
4663 case DT_RELSZ:
4664 case DT_RELASZ:
4665 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4666 type = SHT_REL;
4667 else
4668 type = SHT_RELA;
4669 dyn.d_un.d_val = 0;
4670 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4672 Elf_Internal_Shdr *hdr;
4674 hdr = elf_elfsections (abfd)[i];
4675 if (hdr->sh_type == type
4676 && (hdr->sh_flags & SHF_ALLOC) != 0)
4678 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4679 dyn.d_un.d_val += hdr->sh_size;
4680 else
4682 if (dyn.d_un.d_val == 0
4683 || hdr->sh_addr < dyn.d_un.d_val)
4684 dyn.d_un.d_val = hdr->sh_addr;
4688 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4689 break;
4694 /* If we have created any dynamic sections, then output them. */
4695 if (dynobj != NULL)
4697 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4698 goto error_return;
4700 for (o = dynobj->sections; o != NULL; o = o->next)
4702 if ((o->flags & SEC_HAS_CONTENTS) == 0
4703 || o->_raw_size == 0)
4704 continue;
4705 if ((o->flags & SEC_LINKER_CREATED) == 0)
4707 /* At this point, we are only interested in sections
4708 created by elf_link_create_dynamic_sections. */
4709 continue;
4711 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4712 != SHT_STRTAB)
4713 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4715 if (! bfd_set_section_contents (abfd, o->output_section,
4716 o->contents, o->output_offset,
4717 o->_raw_size))
4718 goto error_return;
4720 else
4722 file_ptr off;
4724 /* The contents of the .dynstr section are actually in a
4725 stringtab. */
4726 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4727 if (bfd_seek (abfd, off, SEEK_SET) != 0
4728 || ! _bfd_stringtab_emit (abfd,
4729 elf_hash_table (info)->dynstr))
4730 goto error_return;
4735 /* If we have optimized stabs strings, output them. */
4736 if (elf_hash_table (info)->stab_info != NULL)
4738 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4739 goto error_return;
4742 if (finfo.symstrtab != NULL)
4743 _bfd_stringtab_free (finfo.symstrtab);
4744 if (finfo.contents != NULL)
4745 free (finfo.contents);
4746 if (finfo.external_relocs != NULL)
4747 free (finfo.external_relocs);
4748 if (finfo.internal_relocs != NULL)
4749 free (finfo.internal_relocs);
4750 if (finfo.external_syms != NULL)
4751 free (finfo.external_syms);
4752 if (finfo.internal_syms != NULL)
4753 free (finfo.internal_syms);
4754 if (finfo.indices != NULL)
4755 free (finfo.indices);
4756 if (finfo.sections != NULL)
4757 free (finfo.sections);
4758 if (finfo.symbuf != NULL)
4759 free (finfo.symbuf);
4760 for (o = abfd->sections; o != NULL; o = o->next)
4762 if ((o->flags & SEC_RELOC) != 0
4763 && elf_section_data (o)->rel_hashes != NULL)
4764 free (elf_section_data (o)->rel_hashes);
4767 elf_tdata (abfd)->linker = true;
4769 return true;
4771 error_return:
4772 if (finfo.symstrtab != NULL)
4773 _bfd_stringtab_free (finfo.symstrtab);
4774 if (finfo.contents != NULL)
4775 free (finfo.contents);
4776 if (finfo.external_relocs != NULL)
4777 free (finfo.external_relocs);
4778 if (finfo.internal_relocs != NULL)
4779 free (finfo.internal_relocs);
4780 if (finfo.external_syms != NULL)
4781 free (finfo.external_syms);
4782 if (finfo.internal_syms != NULL)
4783 free (finfo.internal_syms);
4784 if (finfo.indices != NULL)
4785 free (finfo.indices);
4786 if (finfo.sections != NULL)
4787 free (finfo.sections);
4788 if (finfo.symbuf != NULL)
4789 free (finfo.symbuf);
4790 for (o = abfd->sections; o != NULL; o = o->next)
4792 if ((o->flags & SEC_RELOC) != 0
4793 && elf_section_data (o)->rel_hashes != NULL)
4794 free (elf_section_data (o)->rel_hashes);
4797 return false;
4800 /* Add a symbol to the output symbol table. */
4802 static boolean
4803 elf_link_output_sym (finfo, name, elfsym, input_sec)
4804 struct elf_final_link_info *finfo;
4805 const char *name;
4806 Elf_Internal_Sym *elfsym;
4807 asection *input_sec;
4809 boolean (*output_symbol_hook) PARAMS ((bfd *,
4810 struct bfd_link_info *info,
4811 const char *,
4812 Elf_Internal_Sym *,
4813 asection *));
4815 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4816 elf_backend_link_output_symbol_hook;
4817 if (output_symbol_hook != NULL)
4819 if (! ((*output_symbol_hook)
4820 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4821 return false;
4824 if (name == (const char *) NULL || *name == '\0')
4825 elfsym->st_name = 0;
4826 else if (input_sec->flags & SEC_EXCLUDE)
4827 elfsym->st_name = 0;
4828 else
4830 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4831 name, true,
4832 false);
4833 if (elfsym->st_name == (unsigned long) -1)
4834 return false;
4837 if (finfo->symbuf_count >= finfo->symbuf_size)
4839 if (! elf_link_flush_output_syms (finfo))
4840 return false;
4843 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4844 (PTR) (finfo->symbuf + finfo->symbuf_count));
4845 ++finfo->symbuf_count;
4847 ++ bfd_get_symcount (finfo->output_bfd);
4849 return true;
4852 /* Flush the output symbols to the file. */
4854 static boolean
4855 elf_link_flush_output_syms (finfo)
4856 struct elf_final_link_info *finfo;
4858 if (finfo->symbuf_count > 0)
4860 Elf_Internal_Shdr *symtab;
4862 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4864 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4865 SEEK_SET) != 0
4866 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4867 sizeof (Elf_External_Sym), finfo->output_bfd)
4868 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4869 return false;
4871 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4873 finfo->symbuf_count = 0;
4876 return true;
4879 /* Add an external symbol to the symbol table. This is called from
4880 the hash table traversal routine. When generating a shared object,
4881 we go through the symbol table twice. The first time we output
4882 anything that might have been forced to local scope in a version
4883 script. The second time we output the symbols that are still
4884 global symbols. */
4886 static boolean
4887 elf_link_output_extsym (h, data)
4888 struct elf_link_hash_entry *h;
4889 PTR data;
4891 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4892 struct elf_final_link_info *finfo = eoinfo->finfo;
4893 boolean strip;
4894 Elf_Internal_Sym sym;
4895 asection *input_sec;
4897 /* Decide whether to output this symbol in this pass. */
4898 if (eoinfo->localsyms)
4900 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4901 return true;
4903 else
4905 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4906 return true;
4909 /* If we are not creating a shared library, and this symbol is
4910 referenced by a shared library but is not defined anywhere, then
4911 warn that it is undefined. If we do not do this, the runtime
4912 linker will complain that the symbol is undefined when the
4913 program is run. We don't have to worry about symbols that are
4914 referenced by regular files, because we will already have issued
4915 warnings for them. */
4916 if (! finfo->info->relocateable
4917 && ! (finfo->info->shared
4918 && !finfo->info->no_undefined)
4919 && h->root.type == bfd_link_hash_undefined
4920 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4921 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4923 if (! ((*finfo->info->callbacks->undefined_symbol)
4924 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4925 (asection *) NULL, 0, true)))
4927 eoinfo->failed = true;
4928 return false;
4932 /* We don't want to output symbols that have never been mentioned by
4933 a regular file, or that we have been told to strip. However, if
4934 h->indx is set to -2, the symbol is used by a reloc and we must
4935 output it. */
4936 if (h->indx == -2)
4937 strip = false;
4938 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4939 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4940 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4941 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4942 strip = true;
4943 else if (finfo->info->strip == strip_all
4944 || (finfo->info->strip == strip_some
4945 && bfd_hash_lookup (finfo->info->keep_hash,
4946 h->root.root.string,
4947 false, false) == NULL))
4948 strip = true;
4949 else
4950 strip = false;
4952 /* If we're stripping it, and it's not a dynamic symbol, there's
4953 nothing else to do unless it is a forced local symbol. */
4954 if (strip
4955 && h->dynindx == -1
4956 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4957 return true;
4959 sym.st_value = 0;
4960 sym.st_size = h->size;
4961 sym.st_other = h->other;
4962 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4963 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4964 else if (h->root.type == bfd_link_hash_undefweak
4965 || h->root.type == bfd_link_hash_defweak)
4966 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4967 else
4968 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4970 switch (h->root.type)
4972 default:
4973 case bfd_link_hash_new:
4974 abort ();
4975 return false;
4977 case bfd_link_hash_undefined:
4978 input_sec = bfd_und_section_ptr;
4979 sym.st_shndx = SHN_UNDEF;
4980 break;
4982 case bfd_link_hash_undefweak:
4983 input_sec = bfd_und_section_ptr;
4984 sym.st_shndx = SHN_UNDEF;
4985 break;
4987 case bfd_link_hash_defined:
4988 case bfd_link_hash_defweak:
4990 input_sec = h->root.u.def.section;
4991 if (input_sec->output_section != NULL)
4993 sym.st_shndx =
4994 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4995 input_sec->output_section);
4996 if (sym.st_shndx == (unsigned short) -1)
4998 (*_bfd_error_handler)
4999 (_("%s: could not find output section %s for input section %s"),
5000 bfd_get_filename (finfo->output_bfd),
5001 input_sec->output_section->name,
5002 input_sec->name);
5003 eoinfo->failed = true;
5004 return false;
5007 /* ELF symbols in relocateable files are section relative,
5008 but in nonrelocateable files they are virtual
5009 addresses. */
5010 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5011 if (! finfo->info->relocateable)
5012 sym.st_value += input_sec->output_section->vma;
5014 else
5016 BFD_ASSERT (input_sec->owner == NULL
5017 || (input_sec->owner->flags & DYNAMIC) != 0);
5018 sym.st_shndx = SHN_UNDEF;
5019 input_sec = bfd_und_section_ptr;
5022 break;
5024 case bfd_link_hash_common:
5025 input_sec = h->root.u.c.p->section;
5026 sym.st_shndx = SHN_COMMON;
5027 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5028 break;
5030 case bfd_link_hash_indirect:
5031 /* These symbols are created by symbol versioning. They point
5032 to the decorated version of the name. For example, if the
5033 symbol foo@@GNU_1.2 is the default, which should be used when
5034 foo is used with no version, then we add an indirect symbol
5035 foo which points to foo@@GNU_1.2. We ignore these symbols,
5036 since the indirected symbol is already in the hash table. */
5037 return true;
5039 /* Fall through. */
5040 case bfd_link_hash_warning:
5041 /* We can't represent these symbols in ELF, although a warning
5042 symbol may have come from a .gnu.warning.SYMBOL section. We
5043 just put the target symbol in the hash table. If the target
5044 symbol does not really exist, don't do anything. */
5045 if (h->root.u.i.link->type == bfd_link_hash_new)
5046 return true;
5047 return (elf_link_output_extsym
5048 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5051 /* Give the processor backend a chance to tweak the symbol value,
5052 and also to finish up anything that needs to be done for this
5053 symbol. */
5054 if ((h->dynindx != -1
5055 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5056 && elf_hash_table (finfo->info)->dynamic_sections_created)
5058 struct elf_backend_data *bed;
5060 bed = get_elf_backend_data (finfo->output_bfd);
5061 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5062 (finfo->output_bfd, finfo->info, h, &sym)))
5064 eoinfo->failed = true;
5065 return false;
5069 /* If we are marking the symbol as undefined, and there are no
5070 non-weak references to this symbol from a regular object, then
5071 mark the symbol as weak undefined; if there are non-weak
5072 references, mark the symbol as strong. We can't do this earlier,
5073 because it might not be marked as undefined until the
5074 finish_dynamic_symbol routine gets through with it. */
5075 if (sym.st_shndx == SHN_UNDEF
5076 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5077 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5078 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5080 int bindtype;
5082 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5083 bindtype = STB_GLOBAL;
5084 else
5085 bindtype = STB_WEAK;
5086 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5089 /* If a symbol is not defined locally, we clear the visibility
5090 field. */
5091 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5092 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5094 /* If this symbol should be put in the .dynsym section, then put it
5095 there now. We have already know the symbol index. We also fill
5096 in the entry in the .hash section. */
5097 if (h->dynindx != -1
5098 && elf_hash_table (finfo->info)->dynamic_sections_created)
5100 size_t bucketcount;
5101 size_t bucket;
5102 size_t hash_entry_size;
5103 bfd_byte *bucketpos;
5104 bfd_vma chain;
5106 sym.st_name = h->dynstr_index;
5108 elf_swap_symbol_out (finfo->output_bfd, &sym,
5109 (PTR) (((Elf_External_Sym *)
5110 finfo->dynsym_sec->contents)
5111 + h->dynindx));
5113 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5114 bucket = h->elf_hash_value % bucketcount;
5115 hash_entry_size
5116 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5117 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5118 + (bucket + 2) * hash_entry_size);
5119 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5120 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5121 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5122 ((bfd_byte *) finfo->hash_sec->contents
5123 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5125 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5127 Elf_Internal_Versym iversym;
5129 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5131 if (h->verinfo.verdef == NULL)
5132 iversym.vs_vers = 0;
5133 else
5134 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5136 else
5138 if (h->verinfo.vertree == NULL)
5139 iversym.vs_vers = 1;
5140 else
5141 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5144 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5145 iversym.vs_vers |= VERSYM_HIDDEN;
5147 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5148 (((Elf_External_Versym *)
5149 finfo->symver_sec->contents)
5150 + h->dynindx));
5154 /* If we're stripping it, then it was just a dynamic symbol, and
5155 there's nothing else to do. */
5156 if (strip)
5157 return true;
5159 h->indx = bfd_get_symcount (finfo->output_bfd);
5161 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5163 eoinfo->failed = true;
5164 return false;
5167 return true;
5170 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5171 originated from the section given by INPUT_REL_HDR) to the
5172 OUTPUT_BFD. */
5174 static void
5175 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5176 internal_relocs)
5177 bfd *output_bfd;
5178 asection *input_section;
5179 Elf_Internal_Shdr *input_rel_hdr;
5180 Elf_Internal_Rela *internal_relocs;
5182 Elf_Internal_Rela *irela;
5183 Elf_Internal_Rela *irelaend;
5184 Elf_Internal_Shdr *output_rel_hdr;
5185 asection *output_section;
5186 unsigned int *rel_countp = NULL;
5188 output_section = input_section->output_section;
5189 output_rel_hdr = NULL;
5191 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5192 == input_rel_hdr->sh_entsize)
5194 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5195 rel_countp = &elf_section_data (output_section)->rel_count;
5197 else if (elf_section_data (output_section)->rel_hdr2
5198 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5199 == input_rel_hdr->sh_entsize))
5201 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5202 rel_countp = &elf_section_data (output_section)->rel_count2;
5205 BFD_ASSERT (output_rel_hdr != NULL);
5207 irela = internal_relocs;
5208 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5209 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5211 Elf_External_Rel *erel;
5213 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5214 for (; irela < irelaend; irela++, erel++)
5216 Elf_Internal_Rel irel;
5218 irel.r_offset = irela->r_offset;
5219 irel.r_info = irela->r_info;
5220 BFD_ASSERT (irela->r_addend == 0);
5221 elf_swap_reloc_out (output_bfd, &irel, erel);
5224 else
5226 Elf_External_Rela *erela;
5228 BFD_ASSERT (input_rel_hdr->sh_entsize
5229 == sizeof (Elf_External_Rela));
5230 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5231 for (; irela < irelaend; irela++, erela++)
5232 elf_swap_reloca_out (output_bfd, irela, erela);
5235 /* Bump the counter, so that we know where to add the next set of
5236 relocations. */
5237 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5240 /* Link an input file into the linker output file. This function
5241 handles all the sections and relocations of the input file at once.
5242 This is so that we only have to read the local symbols once, and
5243 don't have to keep them in memory. */
5245 static boolean
5246 elf_link_input_bfd (finfo, input_bfd)
5247 struct elf_final_link_info *finfo;
5248 bfd *input_bfd;
5250 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5251 bfd *, asection *, bfd_byte *,
5252 Elf_Internal_Rela *,
5253 Elf_Internal_Sym *, asection **));
5254 bfd *output_bfd;
5255 Elf_Internal_Shdr *symtab_hdr;
5256 size_t locsymcount;
5257 size_t extsymoff;
5258 Elf_External_Sym *external_syms;
5259 Elf_External_Sym *esym;
5260 Elf_External_Sym *esymend;
5261 Elf_Internal_Sym *isym;
5262 long *pindex;
5263 asection **ppsection;
5264 asection *o;
5265 struct elf_backend_data *bed;
5267 output_bfd = finfo->output_bfd;
5268 bed = get_elf_backend_data (output_bfd);
5269 relocate_section = bed->elf_backend_relocate_section;
5271 /* If this is a dynamic object, we don't want to do anything here:
5272 we don't want the local symbols, and we don't want the section
5273 contents. */
5274 if ((input_bfd->flags & DYNAMIC) != 0)
5275 return true;
5277 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5278 if (elf_bad_symtab (input_bfd))
5280 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5281 extsymoff = 0;
5283 else
5285 locsymcount = symtab_hdr->sh_info;
5286 extsymoff = symtab_hdr->sh_info;
5289 /* Read the local symbols. */
5290 if (symtab_hdr->contents != NULL)
5291 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5292 else if (locsymcount == 0)
5293 external_syms = NULL;
5294 else
5296 external_syms = finfo->external_syms;
5297 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5298 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5299 locsymcount, input_bfd)
5300 != locsymcount * sizeof (Elf_External_Sym)))
5301 return false;
5304 /* Swap in the local symbols and write out the ones which we know
5305 are going into the output file. */
5306 esym = external_syms;
5307 esymend = esym + locsymcount;
5308 isym = finfo->internal_syms;
5309 pindex = finfo->indices;
5310 ppsection = finfo->sections;
5311 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5313 asection *isec;
5314 const char *name;
5315 Elf_Internal_Sym osym;
5317 elf_swap_symbol_in (input_bfd, esym, isym);
5318 *pindex = -1;
5320 if (elf_bad_symtab (input_bfd))
5322 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5324 *ppsection = NULL;
5325 continue;
5329 if (isym->st_shndx == SHN_UNDEF)
5330 isec = bfd_und_section_ptr;
5331 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5332 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5333 else if (isym->st_shndx == SHN_ABS)
5334 isec = bfd_abs_section_ptr;
5335 else if (isym->st_shndx == SHN_COMMON)
5336 isec = bfd_com_section_ptr;
5337 else
5339 /* Who knows? */
5340 isec = NULL;
5343 *ppsection = isec;
5345 /* Don't output the first, undefined, symbol. */
5346 if (esym == external_syms)
5347 continue;
5349 /* If we are stripping all symbols, we don't want to output this
5350 one. */
5351 if (finfo->info->strip == strip_all)
5352 continue;
5354 /* We never output section symbols. Instead, we use the section
5355 symbol of the corresponding section in the output file. */
5356 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5357 continue;
5359 /* If we are discarding all local symbols, we don't want to
5360 output this one. If we are generating a relocateable output
5361 file, then some of the local symbols may be required by
5362 relocs; we output them below as we discover that they are
5363 needed. */
5364 if (finfo->info->discard == discard_all)
5365 continue;
5367 /* If this symbol is defined in a section which we are
5368 discarding, we don't need to keep it, but note that
5369 linker_mark is only reliable for sections that have contents.
5370 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5371 as well as linker_mark. */
5372 if (isym->st_shndx > 0
5373 && isym->st_shndx < SHN_LORESERVE
5374 && isec != NULL
5375 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5376 || (! finfo->info->relocateable
5377 && (isec->flags & SEC_EXCLUDE) != 0)))
5378 continue;
5380 /* Get the name of the symbol. */
5381 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5382 isym->st_name);
5383 if (name == NULL)
5384 return false;
5386 /* See if we are discarding symbols with this name. */
5387 if ((finfo->info->strip == strip_some
5388 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5389 == NULL))
5390 || (finfo->info->discard == discard_l
5391 && bfd_is_local_label_name (input_bfd, name)))
5392 continue;
5394 /* If we get here, we are going to output this symbol. */
5396 osym = *isym;
5398 /* Adjust the section index for the output file. */
5399 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5400 isec->output_section);
5401 if (osym.st_shndx == (unsigned short) -1)
5402 return false;
5404 *pindex = bfd_get_symcount (output_bfd);
5406 /* ELF symbols in relocateable files are section relative, but
5407 in executable files they are virtual addresses. Note that
5408 this code assumes that all ELF sections have an associated
5409 BFD section with a reasonable value for output_offset; below
5410 we assume that they also have a reasonable value for
5411 output_section. Any special sections must be set up to meet
5412 these requirements. */
5413 osym.st_value += isec->output_offset;
5414 if (! finfo->info->relocateable)
5415 osym.st_value += isec->output_section->vma;
5417 if (! elf_link_output_sym (finfo, name, &osym, isec))
5418 return false;
5421 /* Relocate the contents of each section. */
5422 for (o = input_bfd->sections; o != NULL; o = o->next)
5424 bfd_byte *contents;
5426 if (! o->linker_mark)
5428 /* This section was omitted from the link. */
5429 continue;
5432 if ((o->flags & SEC_HAS_CONTENTS) == 0
5433 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5434 continue;
5436 if ((o->flags & SEC_LINKER_CREATED) != 0)
5438 /* Section was created by elf_link_create_dynamic_sections
5439 or somesuch. */
5440 continue;
5443 /* Get the contents of the section. They have been cached by a
5444 relaxation routine. Note that o is a section in an input
5445 file, so the contents field will not have been set by any of
5446 the routines which work on output files. */
5447 if (elf_section_data (o)->this_hdr.contents != NULL)
5448 contents = elf_section_data (o)->this_hdr.contents;
5449 else
5451 contents = finfo->contents;
5452 if (! bfd_get_section_contents (input_bfd, o, contents,
5453 (file_ptr) 0, o->_raw_size))
5454 return false;
5457 if ((o->flags & SEC_RELOC) != 0)
5459 Elf_Internal_Rela *internal_relocs;
5461 /* Get the swapped relocs. */
5462 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5463 (input_bfd, o, finfo->external_relocs,
5464 finfo->internal_relocs, false));
5465 if (internal_relocs == NULL
5466 && o->reloc_count > 0)
5467 return false;
5469 /* Relocate the section by invoking a back end routine.
5471 The back end routine is responsible for adjusting the
5472 section contents as necessary, and (if using Rela relocs
5473 and generating a relocateable output file) adjusting the
5474 reloc addend as necessary.
5476 The back end routine does not have to worry about setting
5477 the reloc address or the reloc symbol index.
5479 The back end routine is given a pointer to the swapped in
5480 internal symbols, and can access the hash table entries
5481 for the external symbols via elf_sym_hashes (input_bfd).
5483 When generating relocateable output, the back end routine
5484 must handle STB_LOCAL/STT_SECTION symbols specially. The
5485 output symbol is going to be a section symbol
5486 corresponding to the output section, which will require
5487 the addend to be adjusted. */
5489 if (! (*relocate_section) (output_bfd, finfo->info,
5490 input_bfd, o, contents,
5491 internal_relocs,
5492 finfo->internal_syms,
5493 finfo->sections))
5494 return false;
5496 if (finfo->info->relocateable || finfo->info->emitrelocations)
5498 Elf_Internal_Rela *irela;
5499 Elf_Internal_Rela *irelaend;
5500 struct elf_link_hash_entry **rel_hash;
5501 Elf_Internal_Shdr *input_rel_hdr;
5503 /* Adjust the reloc addresses and symbol indices. */
5505 irela = internal_relocs;
5506 irelaend =
5507 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5508 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5509 + elf_section_data (o->output_section)->rel_count
5510 + elf_section_data (o->output_section)->rel_count2);
5511 for (; irela < irelaend; irela++, rel_hash++)
5513 unsigned long r_symndx;
5514 Elf_Internal_Sym *isym;
5515 asection *sec;
5517 irela->r_offset += o->output_offset;
5519 /* Relocs in an executable have to be virtual addresses. */
5520 if (finfo->info->emitrelocations)
5521 irela->r_offset += o->output_section->vma;
5523 r_symndx = ELF_R_SYM (irela->r_info);
5525 if (r_symndx == 0)
5526 continue;
5528 if (r_symndx >= locsymcount
5529 || (elf_bad_symtab (input_bfd)
5530 && finfo->sections[r_symndx] == NULL))
5532 struct elf_link_hash_entry *rh;
5533 long indx;
5535 /* This is a reloc against a global symbol. We
5536 have not yet output all the local symbols, so
5537 we do not know the symbol index of any global
5538 symbol. We set the rel_hash entry for this
5539 reloc to point to the global hash table entry
5540 for this symbol. The symbol index is then
5541 set at the end of elf_bfd_final_link. */
5542 indx = r_symndx - extsymoff;
5543 rh = elf_sym_hashes (input_bfd)[indx];
5544 while (rh->root.type == bfd_link_hash_indirect
5545 || rh->root.type == bfd_link_hash_warning)
5546 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5548 /* Setting the index to -2 tells
5549 elf_link_output_extsym that this symbol is
5550 used by a reloc. */
5551 BFD_ASSERT (rh->indx < 0);
5552 rh->indx = -2;
5554 *rel_hash = rh;
5556 continue;
5559 /* This is a reloc against a local symbol. */
5561 *rel_hash = NULL;
5562 isym = finfo->internal_syms + r_symndx;
5563 sec = finfo->sections[r_symndx];
5564 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5566 /* I suppose the backend ought to fill in the
5567 section of any STT_SECTION symbol against a
5568 processor specific section. If we have
5569 discarded a section, the output_section will
5570 be the absolute section. */
5571 if (sec != NULL
5572 && (bfd_is_abs_section (sec)
5573 || (sec->output_section != NULL
5574 && bfd_is_abs_section (sec->output_section))))
5575 r_symndx = 0;
5576 else if (sec == NULL || sec->owner == NULL)
5578 bfd_set_error (bfd_error_bad_value);
5579 return false;
5581 else
5583 r_symndx = sec->output_section->target_index;
5584 BFD_ASSERT (r_symndx != 0);
5587 else
5589 if (finfo->indices[r_symndx] == -1)
5591 unsigned long link;
5592 const char *name;
5593 asection *osec;
5595 if (finfo->info->strip == strip_all)
5597 /* You can't do ld -r -s. */
5598 bfd_set_error (bfd_error_invalid_operation);
5599 return false;
5602 /* This symbol was skipped earlier, but
5603 since it is needed by a reloc, we
5604 must output it now. */
5605 link = symtab_hdr->sh_link;
5606 name = bfd_elf_string_from_elf_section (input_bfd,
5607 link,
5608 isym->st_name);
5609 if (name == NULL)
5610 return false;
5612 osec = sec->output_section;
5613 isym->st_shndx =
5614 _bfd_elf_section_from_bfd_section (output_bfd,
5615 osec);
5616 if (isym->st_shndx == (unsigned short) -1)
5617 return false;
5619 isym->st_value += sec->output_offset;
5620 if (! finfo->info->relocateable)
5621 isym->st_value += osec->vma;
5623 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5625 if (! elf_link_output_sym (finfo, name, isym, sec))
5626 return false;
5629 r_symndx = finfo->indices[r_symndx];
5632 irela->r_info = ELF_R_INFO (r_symndx,
5633 ELF_R_TYPE (irela->r_info));
5636 /* Swap out the relocs. */
5637 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5638 elf_link_output_relocs (output_bfd, o,
5639 input_rel_hdr,
5640 internal_relocs);
5641 internal_relocs
5642 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5643 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5644 if (input_rel_hdr)
5645 elf_link_output_relocs (output_bfd, o,
5646 input_rel_hdr,
5647 internal_relocs);
5651 /* Write out the modified section contents. */
5652 if (elf_section_data (o)->stab_info == NULL)
5654 if (! (o->flags & SEC_EXCLUDE) &&
5655 ! bfd_set_section_contents (output_bfd, o->output_section,
5656 contents, o->output_offset,
5657 (o->_cooked_size != 0
5658 ? o->_cooked_size
5659 : o->_raw_size)))
5660 return false;
5662 else
5664 if (! (_bfd_write_section_stabs
5665 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5666 o, &elf_section_data (o)->stab_info, contents)))
5667 return false;
5671 return true;
5674 /* Generate a reloc when linking an ELF file. This is a reloc
5675 requested by the linker, and does come from any input file. This
5676 is used to build constructor and destructor tables when linking
5677 with -Ur. */
5679 static boolean
5680 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5681 bfd *output_bfd;
5682 struct bfd_link_info *info;
5683 asection *output_section;
5684 struct bfd_link_order *link_order;
5686 reloc_howto_type *howto;
5687 long indx;
5688 bfd_vma offset;
5689 bfd_vma addend;
5690 struct elf_link_hash_entry **rel_hash_ptr;
5691 Elf_Internal_Shdr *rel_hdr;
5693 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5694 if (howto == NULL)
5696 bfd_set_error (bfd_error_bad_value);
5697 return false;
5700 addend = link_order->u.reloc.p->addend;
5702 /* Figure out the symbol index. */
5703 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5704 + elf_section_data (output_section)->rel_count
5705 + elf_section_data (output_section)->rel_count2);
5706 if (link_order->type == bfd_section_reloc_link_order)
5708 indx = link_order->u.reloc.p->u.section->target_index;
5709 BFD_ASSERT (indx != 0);
5710 *rel_hash_ptr = NULL;
5712 else
5714 struct elf_link_hash_entry *h;
5716 /* Treat a reloc against a defined symbol as though it were
5717 actually against the section. */
5718 h = ((struct elf_link_hash_entry *)
5719 bfd_wrapped_link_hash_lookup (output_bfd, info,
5720 link_order->u.reloc.p->u.name,
5721 false, false, true));
5722 if (h != NULL
5723 && (h->root.type == bfd_link_hash_defined
5724 || h->root.type == bfd_link_hash_defweak))
5726 asection *section;
5728 section = h->root.u.def.section;
5729 indx = section->output_section->target_index;
5730 *rel_hash_ptr = NULL;
5731 /* It seems that we ought to add the symbol value to the
5732 addend here, but in practice it has already been added
5733 because it was passed to constructor_callback. */
5734 addend += section->output_section->vma + section->output_offset;
5736 else if (h != NULL)
5738 /* Setting the index to -2 tells elf_link_output_extsym that
5739 this symbol is used by a reloc. */
5740 h->indx = -2;
5741 *rel_hash_ptr = h;
5742 indx = 0;
5744 else
5746 if (! ((*info->callbacks->unattached_reloc)
5747 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5748 (asection *) NULL, (bfd_vma) 0)))
5749 return false;
5750 indx = 0;
5754 /* If this is an inplace reloc, we must write the addend into the
5755 object file. */
5756 if (howto->partial_inplace && addend != 0)
5758 bfd_size_type size;
5759 bfd_reloc_status_type rstat;
5760 bfd_byte *buf;
5761 boolean ok;
5763 size = bfd_get_reloc_size (howto);
5764 buf = (bfd_byte *) bfd_zmalloc (size);
5765 if (buf == (bfd_byte *) NULL)
5766 return false;
5767 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5768 switch (rstat)
5770 case bfd_reloc_ok:
5771 break;
5772 default:
5773 case bfd_reloc_outofrange:
5774 abort ();
5775 case bfd_reloc_overflow:
5776 if (! ((*info->callbacks->reloc_overflow)
5777 (info,
5778 (link_order->type == bfd_section_reloc_link_order
5779 ? bfd_section_name (output_bfd,
5780 link_order->u.reloc.p->u.section)
5781 : link_order->u.reloc.p->u.name),
5782 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5783 (bfd_vma) 0)))
5785 free (buf);
5786 return false;
5788 break;
5790 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5791 (file_ptr) link_order->offset, size);
5792 free (buf);
5793 if (! ok)
5794 return false;
5797 /* The address of a reloc is relative to the section in a
5798 relocateable file, and is a virtual address in an executable
5799 file. */
5800 offset = link_order->offset;
5801 if (! info->relocateable)
5802 offset += output_section->vma;
5804 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5806 if (rel_hdr->sh_type == SHT_REL)
5808 Elf_Internal_Rel irel;
5809 Elf_External_Rel *erel;
5811 irel.r_offset = offset;
5812 irel.r_info = ELF_R_INFO (indx, howto->type);
5813 erel = ((Elf_External_Rel *) rel_hdr->contents
5814 + elf_section_data (output_section)->rel_count);
5815 elf_swap_reloc_out (output_bfd, &irel, erel);
5817 else
5819 Elf_Internal_Rela irela;
5820 Elf_External_Rela *erela;
5822 irela.r_offset = offset;
5823 irela.r_info = ELF_R_INFO (indx, howto->type);
5824 irela.r_addend = addend;
5825 erela = ((Elf_External_Rela *) rel_hdr->contents
5826 + elf_section_data (output_section)->rel_count);
5827 elf_swap_reloca_out (output_bfd, &irela, erela);
5830 ++elf_section_data (output_section)->rel_count;
5832 return true;
5836 /* Allocate a pointer to live in a linker created section. */
5838 boolean
5839 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5840 bfd *abfd;
5841 struct bfd_link_info *info;
5842 elf_linker_section_t *lsect;
5843 struct elf_link_hash_entry *h;
5844 const Elf_Internal_Rela *rel;
5846 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5847 elf_linker_section_pointers_t *linker_section_ptr;
5848 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5850 BFD_ASSERT (lsect != NULL);
5852 /* Is this a global symbol? */
5853 if (h != NULL)
5855 /* Has this symbol already been allocated, if so, our work is done */
5856 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5857 rel->r_addend,
5858 lsect->which))
5859 return true;
5861 ptr_linker_section_ptr = &h->linker_section_pointer;
5862 /* Make sure this symbol is output as a dynamic symbol. */
5863 if (h->dynindx == -1)
5865 if (! elf_link_record_dynamic_symbol (info, h))
5866 return false;
5869 if (lsect->rel_section)
5870 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5873 else /* Allocation of a pointer to a local symbol */
5875 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5877 /* Allocate a table to hold the local symbols if first time */
5878 if (!ptr)
5880 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5881 register unsigned int i;
5883 ptr = (elf_linker_section_pointers_t **)
5884 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5886 if (!ptr)
5887 return false;
5889 elf_local_ptr_offsets (abfd) = ptr;
5890 for (i = 0; i < num_symbols; i++)
5891 ptr[i] = (elf_linker_section_pointers_t *)0;
5894 /* Has this symbol already been allocated, if so, our work is done */
5895 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5896 rel->r_addend,
5897 lsect->which))
5898 return true;
5900 ptr_linker_section_ptr = &ptr[r_symndx];
5902 if (info->shared)
5904 /* If we are generating a shared object, we need to
5905 output a R_<xxx>_RELATIVE reloc so that the
5906 dynamic linker can adjust this GOT entry. */
5907 BFD_ASSERT (lsect->rel_section != NULL);
5908 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5912 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5913 from internal memory. */
5914 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5915 linker_section_ptr = (elf_linker_section_pointers_t *)
5916 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5918 if (!linker_section_ptr)
5919 return false;
5921 linker_section_ptr->next = *ptr_linker_section_ptr;
5922 linker_section_ptr->addend = rel->r_addend;
5923 linker_section_ptr->which = lsect->which;
5924 linker_section_ptr->written_address_p = false;
5925 *ptr_linker_section_ptr = linker_section_ptr;
5927 #if 0
5928 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5930 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5931 lsect->hole_offset += ARCH_SIZE / 8;
5932 lsect->sym_offset += ARCH_SIZE / 8;
5933 if (lsect->sym_hash) /* Bump up symbol value if needed */
5935 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5936 #ifdef DEBUG
5937 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5938 lsect->sym_hash->root.root.string,
5939 (long)ARCH_SIZE / 8,
5940 (long)lsect->sym_hash->root.u.def.value);
5941 #endif
5944 else
5945 #endif
5946 linker_section_ptr->offset = lsect->section->_raw_size;
5948 lsect->section->_raw_size += ARCH_SIZE / 8;
5950 #ifdef DEBUG
5951 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5952 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5953 #endif
5955 return true;
5959 #if ARCH_SIZE==64
5960 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5961 #endif
5962 #if ARCH_SIZE==32
5963 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5964 #endif
5966 /* Fill in the address for a pointer generated in alinker section. */
5968 bfd_vma
5969 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5970 bfd *output_bfd;
5971 bfd *input_bfd;
5972 struct bfd_link_info *info;
5973 elf_linker_section_t *lsect;
5974 struct elf_link_hash_entry *h;
5975 bfd_vma relocation;
5976 const Elf_Internal_Rela *rel;
5977 int relative_reloc;
5979 elf_linker_section_pointers_t *linker_section_ptr;
5981 BFD_ASSERT (lsect != NULL);
5983 if (h != NULL) /* global symbol */
5985 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5986 rel->r_addend,
5987 lsect->which);
5989 BFD_ASSERT (linker_section_ptr != NULL);
5991 if (! elf_hash_table (info)->dynamic_sections_created
5992 || (info->shared
5993 && info->symbolic
5994 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5996 /* This is actually a static link, or it is a
5997 -Bsymbolic link and the symbol is defined
5998 locally. We must initialize this entry in the
5999 global section.
6001 When doing a dynamic link, we create a .rela.<xxx>
6002 relocation entry to initialize the value. This
6003 is done in the finish_dynamic_symbol routine. */
6004 if (!linker_section_ptr->written_address_p)
6006 linker_section_ptr->written_address_p = true;
6007 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6008 lsect->section->contents + linker_section_ptr->offset);
6012 else /* local symbol */
6014 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6015 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6016 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6017 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6018 rel->r_addend,
6019 lsect->which);
6021 BFD_ASSERT (linker_section_ptr != NULL);
6023 /* Write out pointer if it hasn't been rewritten out before */
6024 if (!linker_section_ptr->written_address_p)
6026 linker_section_ptr->written_address_p = true;
6027 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6028 lsect->section->contents + linker_section_ptr->offset);
6030 if (info->shared)
6032 asection *srel = lsect->rel_section;
6033 Elf_Internal_Rela outrel;
6035 /* We need to generate a relative reloc for the dynamic linker. */
6036 if (!srel)
6037 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6038 lsect->rel_name);
6040 BFD_ASSERT (srel != NULL);
6042 outrel.r_offset = (lsect->section->output_section->vma
6043 + lsect->section->output_offset
6044 + linker_section_ptr->offset);
6045 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6046 outrel.r_addend = 0;
6047 elf_swap_reloca_out (output_bfd, &outrel,
6048 (((Elf_External_Rela *)
6049 lsect->section->contents)
6050 + elf_section_data (lsect->section)->rel_count));
6051 ++elf_section_data (lsect->section)->rel_count;
6056 relocation = (lsect->section->output_offset
6057 + linker_section_ptr->offset
6058 - lsect->hole_offset
6059 - lsect->sym_offset);
6061 #ifdef DEBUG
6062 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6063 lsect->name, (long)relocation, (long)relocation);
6064 #endif
6066 /* Subtract out the addend, because it will get added back in by the normal
6067 processing. */
6068 return relocation - linker_section_ptr->addend;
6071 /* Garbage collect unused sections. */
6073 static boolean elf_gc_mark
6074 PARAMS ((struct bfd_link_info *info, asection *sec,
6075 asection * (*gc_mark_hook)
6076 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6077 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6079 static boolean elf_gc_sweep
6080 PARAMS ((struct bfd_link_info *info,
6081 boolean (*gc_sweep_hook)
6082 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6083 const Elf_Internal_Rela *relocs))));
6085 static boolean elf_gc_sweep_symbol
6086 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6088 static boolean elf_gc_allocate_got_offsets
6089 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6091 static boolean elf_gc_propagate_vtable_entries_used
6092 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6094 static boolean elf_gc_smash_unused_vtentry_relocs
6095 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6097 /* The mark phase of garbage collection. For a given section, mark
6098 it, and all the sections which define symbols to which it refers. */
6100 static boolean
6101 elf_gc_mark (info, sec, gc_mark_hook)
6102 struct bfd_link_info *info;
6103 asection *sec;
6104 asection * (*gc_mark_hook)
6105 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6106 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6108 boolean ret = true;
6110 sec->gc_mark = 1;
6112 /* Look through the section relocs. */
6114 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6116 Elf_Internal_Rela *relstart, *rel, *relend;
6117 Elf_Internal_Shdr *symtab_hdr;
6118 struct elf_link_hash_entry **sym_hashes;
6119 size_t nlocsyms;
6120 size_t extsymoff;
6121 Elf_External_Sym *locsyms, *freesyms = NULL;
6122 bfd *input_bfd = sec->owner;
6123 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6125 /* GCFIXME: how to arrange so that relocs and symbols are not
6126 reread continually? */
6128 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6129 sym_hashes = elf_sym_hashes (input_bfd);
6131 /* Read the local symbols. */
6132 if (elf_bad_symtab (input_bfd))
6134 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6135 extsymoff = 0;
6137 else
6138 extsymoff = nlocsyms = symtab_hdr->sh_info;
6139 if (symtab_hdr->contents)
6140 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6141 else if (nlocsyms == 0)
6142 locsyms = NULL;
6143 else
6145 locsyms = freesyms =
6146 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6147 if (freesyms == NULL
6148 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6149 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6150 nlocsyms, input_bfd)
6151 != nlocsyms * sizeof (Elf_External_Sym)))
6153 ret = false;
6154 goto out1;
6158 /* Read the relocations. */
6159 relstart = (NAME(_bfd_elf,link_read_relocs)
6160 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6161 info->keep_memory));
6162 if (relstart == NULL)
6164 ret = false;
6165 goto out1;
6167 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6169 for (rel = relstart; rel < relend; rel++)
6171 unsigned long r_symndx;
6172 asection *rsec;
6173 struct elf_link_hash_entry *h;
6174 Elf_Internal_Sym s;
6176 r_symndx = ELF_R_SYM (rel->r_info);
6177 if (r_symndx == 0)
6178 continue;
6180 if (elf_bad_symtab (sec->owner))
6182 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6183 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6184 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6185 else
6187 h = sym_hashes[r_symndx - extsymoff];
6188 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6191 else if (r_symndx >= nlocsyms)
6193 h = sym_hashes[r_symndx - extsymoff];
6194 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6196 else
6198 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6199 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6202 if (rsec && !rsec->gc_mark)
6203 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6205 ret = false;
6206 goto out2;
6210 out2:
6211 if (!info->keep_memory)
6212 free (relstart);
6213 out1:
6214 if (freesyms)
6215 free (freesyms);
6218 return ret;
6221 /* The sweep phase of garbage collection. Remove all garbage sections. */
6223 static boolean
6224 elf_gc_sweep (info, gc_sweep_hook)
6225 struct bfd_link_info *info;
6226 boolean (*gc_sweep_hook)
6227 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6228 const Elf_Internal_Rela *relocs));
6230 bfd *sub;
6232 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6234 asection *o;
6236 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6237 continue;
6239 for (o = sub->sections; o != NULL; o = o->next)
6241 /* Keep special sections. Keep .debug sections. */
6242 if ((o->flags & SEC_LINKER_CREATED)
6243 || (o->flags & SEC_DEBUGGING))
6244 o->gc_mark = 1;
6246 if (o->gc_mark)
6247 continue;
6249 /* Skip sweeping sections already excluded. */
6250 if (o->flags & SEC_EXCLUDE)
6251 continue;
6253 /* Since this is early in the link process, it is simple
6254 to remove a section from the output. */
6255 o->flags |= SEC_EXCLUDE;
6257 /* But we also have to update some of the relocation
6258 info we collected before. */
6259 if (gc_sweep_hook
6260 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6262 Elf_Internal_Rela *internal_relocs;
6263 boolean r;
6265 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6266 (o->owner, o, NULL, NULL, info->keep_memory));
6267 if (internal_relocs == NULL)
6268 return false;
6270 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6272 if (!info->keep_memory)
6273 free (internal_relocs);
6275 if (!r)
6276 return false;
6281 /* Remove the symbols that were in the swept sections from the dynamic
6282 symbol table. GCFIXME: Anyone know how to get them out of the
6283 static symbol table as well? */
6285 int i = 0;
6287 elf_link_hash_traverse (elf_hash_table (info),
6288 elf_gc_sweep_symbol,
6289 (PTR) &i);
6291 elf_hash_table (info)->dynsymcount = i;
6294 return true;
6297 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6299 static boolean
6300 elf_gc_sweep_symbol (h, idxptr)
6301 struct elf_link_hash_entry *h;
6302 PTR idxptr;
6304 int *idx = (int *) idxptr;
6306 if (h->dynindx != -1
6307 && ((h->root.type != bfd_link_hash_defined
6308 && h->root.type != bfd_link_hash_defweak)
6309 || h->root.u.def.section->gc_mark))
6310 h->dynindx = (*idx)++;
6312 return true;
6315 /* Propogate collected vtable information. This is called through
6316 elf_link_hash_traverse. */
6318 static boolean
6319 elf_gc_propagate_vtable_entries_used (h, okp)
6320 struct elf_link_hash_entry *h;
6321 PTR okp;
6323 /* Those that are not vtables. */
6324 if (h->vtable_parent == NULL)
6325 return true;
6327 /* Those vtables that do not have parents, we cannot merge. */
6328 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6329 return true;
6331 /* If we've already been done, exit. */
6332 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6333 return true;
6335 /* Make sure the parent's table is up to date. */
6336 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6338 if (h->vtable_entries_used == NULL)
6340 /* None of this table's entries were referenced. Re-use the
6341 parent's table. */
6342 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6343 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6345 else
6347 size_t n;
6348 boolean *cu, *pu;
6350 /* Or the parent's entries into ours. */
6351 cu = h->vtable_entries_used;
6352 cu[-1] = true;
6353 pu = h->vtable_parent->vtable_entries_used;
6354 if (pu != NULL)
6356 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6357 while (--n != 0)
6359 if (*pu) *cu = true;
6360 pu++, cu++;
6365 return true;
6368 static boolean
6369 elf_gc_smash_unused_vtentry_relocs (h, okp)
6370 struct elf_link_hash_entry *h;
6371 PTR okp;
6373 asection *sec;
6374 bfd_vma hstart, hend;
6375 Elf_Internal_Rela *relstart, *relend, *rel;
6376 struct elf_backend_data *bed;
6378 /* Take care of both those symbols that do not describe vtables as
6379 well as those that are not loaded. */
6380 if (h->vtable_parent == NULL)
6381 return true;
6383 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6384 || h->root.type == bfd_link_hash_defweak);
6386 sec = h->root.u.def.section;
6387 hstart = h->root.u.def.value;
6388 hend = hstart + h->size;
6390 relstart = (NAME(_bfd_elf,link_read_relocs)
6391 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6392 if (!relstart)
6393 return *(boolean *)okp = false;
6394 bed = get_elf_backend_data (sec->owner);
6395 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6397 for (rel = relstart; rel < relend; ++rel)
6398 if (rel->r_offset >= hstart && rel->r_offset < hend)
6400 /* If the entry is in use, do nothing. */
6401 if (h->vtable_entries_used
6402 && (rel->r_offset - hstart) < h->vtable_entries_size)
6404 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6405 if (h->vtable_entries_used[entry])
6406 continue;
6408 /* Otherwise, kill it. */
6409 rel->r_offset = rel->r_info = rel->r_addend = 0;
6412 return true;
6415 /* Do mark and sweep of unused sections. */
6417 boolean
6418 elf_gc_sections (abfd, info)
6419 bfd *abfd;
6420 struct bfd_link_info *info;
6422 boolean ok = true;
6423 bfd *sub;
6424 asection * (*gc_mark_hook)
6425 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6426 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6428 if (!get_elf_backend_data (abfd)->can_gc_sections
6429 || info->relocateable || info->emitrelocations
6430 || elf_hash_table (info)->dynamic_sections_created)
6431 return true;
6433 /* Apply transitive closure to the vtable entry usage info. */
6434 elf_link_hash_traverse (elf_hash_table (info),
6435 elf_gc_propagate_vtable_entries_used,
6436 (PTR) &ok);
6437 if (!ok)
6438 return false;
6440 /* Kill the vtable relocations that were not used. */
6441 elf_link_hash_traverse (elf_hash_table (info),
6442 elf_gc_smash_unused_vtentry_relocs,
6443 (PTR) &ok);
6444 if (!ok)
6445 return false;
6447 /* Grovel through relocs to find out who stays ... */
6449 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6450 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6452 asection *o;
6454 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6455 continue;
6457 for (o = sub->sections; o != NULL; o = o->next)
6459 if (o->flags & SEC_KEEP)
6460 if (!elf_gc_mark (info, o, gc_mark_hook))
6461 return false;
6465 /* ... and mark SEC_EXCLUDE for those that go. */
6466 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6467 return false;
6469 return true;
6472 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6474 boolean
6475 elf_gc_record_vtinherit (abfd, sec, h, offset)
6476 bfd *abfd;
6477 asection *sec;
6478 struct elf_link_hash_entry *h;
6479 bfd_vma offset;
6481 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6482 struct elf_link_hash_entry **search, *child;
6483 bfd_size_type extsymcount;
6485 /* The sh_info field of the symtab header tells us where the
6486 external symbols start. We don't care about the local symbols at
6487 this point. */
6488 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6489 if (!elf_bad_symtab (abfd))
6490 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6492 sym_hashes = elf_sym_hashes (abfd);
6493 sym_hashes_end = sym_hashes + extsymcount;
6495 /* Hunt down the child symbol, which is in this section at the same
6496 offset as the relocation. */
6497 for (search = sym_hashes; search != sym_hashes_end; ++search)
6499 if ((child = *search) != NULL
6500 && (child->root.type == bfd_link_hash_defined
6501 || child->root.type == bfd_link_hash_defweak)
6502 && child->root.u.def.section == sec
6503 && child->root.u.def.value == offset)
6504 goto win;
6507 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6508 bfd_get_filename (abfd), sec->name,
6509 (unsigned long)offset);
6510 bfd_set_error (bfd_error_invalid_operation);
6511 return false;
6513 win:
6514 if (!h)
6516 /* This *should* only be the absolute section. It could potentially
6517 be that someone has defined a non-global vtable though, which
6518 would be bad. It isn't worth paging in the local symbols to be
6519 sure though; that case should simply be handled by the assembler. */
6521 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6523 else
6524 child->vtable_parent = h;
6526 return true;
6529 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6531 boolean
6532 elf_gc_record_vtentry (abfd, sec, h, addend)
6533 bfd *abfd ATTRIBUTE_UNUSED;
6534 asection *sec ATTRIBUTE_UNUSED;
6535 struct elf_link_hash_entry *h;
6536 bfd_vma addend;
6538 if (addend >= h->vtable_entries_size)
6540 size_t size, bytes;
6541 boolean *ptr = h->vtable_entries_used;
6543 /* While the symbol is undefined, we have to be prepared to handle
6544 a zero size. */
6545 if (h->root.type == bfd_link_hash_undefined)
6546 size = addend;
6547 else
6549 size = h->size;
6550 if (size < addend)
6552 /* Oops! We've got a reference past the defined end of
6553 the table. This is probably a bug -- shall we warn? */
6554 size = addend;
6558 /* Allocate one extra entry for use as a "done" flag for the
6559 consolidation pass. */
6560 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6562 if (ptr)
6564 ptr = bfd_realloc (ptr - 1, bytes);
6566 if (ptr != NULL)
6568 size_t oldbytes;
6570 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6571 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6574 else
6575 ptr = bfd_zmalloc (bytes);
6577 if (ptr == NULL)
6578 return false;
6580 /* And arrange for that done flag to be at index -1. */
6581 h->vtable_entries_used = ptr + 1;
6582 h->vtable_entries_size = size;
6585 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6587 return true;
6590 /* And an accompanying bit to work out final got entry offsets once
6591 we're done. Should be called from final_link. */
6593 boolean
6594 elf_gc_common_finalize_got_offsets (abfd, info)
6595 bfd *abfd;
6596 struct bfd_link_info *info;
6598 bfd *i;
6599 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6600 bfd_vma gotoff;
6602 /* The GOT offset is relative to the .got section, but the GOT header is
6603 put into the .got.plt section, if the backend uses it. */
6604 if (bed->want_got_plt)
6605 gotoff = 0;
6606 else
6607 gotoff = bed->got_header_size;
6609 /* Do the local .got entries first. */
6610 for (i = info->input_bfds; i; i = i->link_next)
6612 bfd_signed_vma *local_got;
6613 bfd_size_type j, locsymcount;
6614 Elf_Internal_Shdr *symtab_hdr;
6616 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6617 continue;
6619 local_got = elf_local_got_refcounts (i);
6620 if (!local_got)
6621 continue;
6623 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6624 if (elf_bad_symtab (i))
6625 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6626 else
6627 locsymcount = symtab_hdr->sh_info;
6629 for (j = 0; j < locsymcount; ++j)
6631 if (local_got[j] > 0)
6633 local_got[j] = gotoff;
6634 gotoff += ARCH_SIZE / 8;
6636 else
6637 local_got[j] = (bfd_vma) -1;
6641 /* Then the global .got entries. .plt refcounts are handled by
6642 adjust_dynamic_symbol */
6643 elf_link_hash_traverse (elf_hash_table (info),
6644 elf_gc_allocate_got_offsets,
6645 (PTR) &gotoff);
6646 return true;
6649 /* We need a special top-level link routine to convert got reference counts
6650 to real got offsets. */
6652 static boolean
6653 elf_gc_allocate_got_offsets (h, offarg)
6654 struct elf_link_hash_entry *h;
6655 PTR offarg;
6657 bfd_vma *off = (bfd_vma *) offarg;
6659 if (h->got.refcount > 0)
6661 h->got.offset = off[0];
6662 off[0] += ARCH_SIZE / 8;
6664 else
6665 h->got.offset = (bfd_vma) -1;
6667 return true;
6670 /* Many folk need no more in the way of final link than this, once
6671 got entry reference counting is enabled. */
6673 boolean
6674 elf_gc_common_final_link (abfd, info)
6675 bfd *abfd;
6676 struct bfd_link_info *info;
6678 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6679 return false;
6681 /* Invoke the regular ELF backend linker to do all the work. */
6682 return elf_bfd_final_link (abfd, info);
6685 /* This function will be called though elf_link_hash_traverse to store
6686 all hash value of the exported symbols in an array. */
6688 static boolean
6689 elf_collect_hash_codes (h, data)
6690 struct elf_link_hash_entry *h;
6691 PTR data;
6693 unsigned long **valuep = (unsigned long **) data;
6694 const char *name;
6695 char *p;
6696 unsigned long ha;
6697 char *alc = NULL;
6699 /* Ignore indirect symbols. These are added by the versioning code. */
6700 if (h->dynindx == -1)
6701 return true;
6703 name = h->root.root.string;
6704 p = strchr (name, ELF_VER_CHR);
6705 if (p != NULL)
6707 alc = bfd_malloc (p - name + 1);
6708 memcpy (alc, name, p - name);
6709 alc[p - name] = '\0';
6710 name = alc;
6713 /* Compute the hash value. */
6714 ha = bfd_elf_hash (name);
6716 /* Store the found hash value in the array given as the argument. */
6717 *(*valuep)++ = ha;
6719 /* And store it in the struct so that we can put it in the hash table
6720 later. */
6721 h->elf_hash_value = ha;
6723 if (alc != NULL)
6724 free (alc);
6726 return true;