1999-12-15 Doug Evans <dje@transmeta.com>
[binutils.git] / bfd / elflink.h
blob01cb6d47f616d1ec3f871de5f9a9b648f7a5a27e
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20 /* ELF linker code. */
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
25 struct elf_info_failed
27 boolean failed;
28 struct bfd_link_info *info;
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
71 switch (bfd_get_format (abfd))
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
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;
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. */
361 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
362 if (element == (bfd *) NULL)
363 goto error_return;
365 if (! bfd_check_format (element, bfd_object))
366 goto error_return;
368 /* Doublecheck that we have not included this object
369 already--it should be impossible, but there may be
370 something wrong with the archive. */
371 if (element->archive_pass != 0)
373 bfd_set_error (bfd_error_bad_value);
374 goto error_return;
376 element->archive_pass = 1;
378 undefs_tail = info->hash->undefs_tail;
380 if (! (*info->callbacks->add_archive_element) (info, element,
381 symdef->name))
382 goto error_return;
383 if (! elf_link_add_object_symbols (element, info))
384 goto error_return;
386 /* If there are any new undefined symbols, we need to make
387 another pass through the archive in order to see whether
388 they can be defined. FIXME: This isn't perfect, because
389 common symbols wind up on undefs_tail and because an
390 undefined symbol which is defined later on in this pass
391 does not require another pass. This isn't a bug, but it
392 does make the code less efficient than it could be. */
393 if (undefs_tail != info->hash->undefs_tail)
394 loop = true;
396 /* Look backward to mark all symbols from this object file
397 which we have already seen in this pass. */
398 mark = i;
401 included[mark] = true;
402 if (mark == 0)
403 break;
404 --mark;
406 while (symdefs[mark].file_offset == symdef->file_offset);
408 /* We mark subsequent symbols from this object file as we go
409 on through the loop. */
410 last = symdef->file_offset;
413 while (loop);
415 free (defined);
416 free (included);
418 return true;
420 error_return:
421 if (defined != (boolean *) NULL)
422 free (defined);
423 if (included != (boolean *) NULL)
424 free (included);
425 return false;
428 /* This function is called when we want to define a new symbol. It
429 handles the various cases which arise when we find a definition in
430 a dynamic object, or when there is already a definition in a
431 dynamic object. The new symbol is described by NAME, SYM, PSEC,
432 and PVALUE. We set SYM_HASH to the hash table entry. We set
433 OVERRIDE if the old symbol is overriding a new definition. We set
434 TYPE_CHANGE_OK if it is OK for the type to change. We set
435 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
436 change, we mean that we shouldn't warn if the type or size does
437 change. */
439 static boolean
440 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
441 override, type_change_ok, size_change_ok)
442 bfd *abfd;
443 struct bfd_link_info *info;
444 const char *name;
445 Elf_Internal_Sym *sym;
446 asection **psec;
447 bfd_vma *pvalue;
448 struct elf_link_hash_entry **sym_hash;
449 boolean *override;
450 boolean *type_change_ok;
451 boolean *size_change_ok;
453 asection *sec;
454 struct elf_link_hash_entry *h;
455 int bind;
456 bfd *oldbfd;
457 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
459 *override = false;
461 sec = *psec;
462 bind = ELF_ST_BIND (sym->st_info);
464 if (! bfd_is_und_section (sec))
465 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
466 else
467 h = ((struct elf_link_hash_entry *)
468 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
469 if (h == NULL)
470 return false;
471 *sym_hash = h;
473 /* This code is for coping with dynamic objects, and is only useful
474 if we are doing an ELF link. */
475 if (info->hash->creator != abfd->xvec)
476 return true;
478 /* For merging, we only care about real symbols. */
480 while (h->root.type == bfd_link_hash_indirect
481 || h->root.type == bfd_link_hash_warning)
482 h = (struct elf_link_hash_entry *) h->root.u.i.link;
484 /* If we just created the symbol, mark it as being an ELF symbol.
485 Other than that, there is nothing to do--there is no merge issue
486 with a newly defined symbol--so we just return. */
488 if (h->root.type == bfd_link_hash_new)
490 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
491 return true;
494 /* OLDBFD is a BFD associated with the existing symbol. */
496 switch (h->root.type)
498 default:
499 oldbfd = NULL;
500 break;
502 case bfd_link_hash_undefined:
503 case bfd_link_hash_undefweak:
504 oldbfd = h->root.u.undef.abfd;
505 break;
507 case bfd_link_hash_defined:
508 case bfd_link_hash_defweak:
509 oldbfd = h->root.u.def.section->owner;
510 break;
512 case bfd_link_hash_common:
513 oldbfd = h->root.u.c.p->section->owner;
514 break;
517 /* In cases involving weak versioned symbols, we may wind up trying
518 to merge a symbol with itself. Catch that here, to avoid the
519 confusion that results if we try to override a symbol with
520 itself. The additional tests catch cases like
521 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
522 dynamic object, which we do want to handle here. */
523 if (abfd == oldbfd
524 && ((abfd->flags & DYNAMIC) == 0
525 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
526 return true;
528 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
529 respectively, is from a dynamic object. */
531 if ((abfd->flags & DYNAMIC) != 0)
532 newdyn = true;
533 else
534 newdyn = false;
536 if (oldbfd != NULL)
537 olddyn = (oldbfd->flags & DYNAMIC) != 0;
538 else
540 asection *hsec;
542 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
543 indices used by MIPS ELF. */
544 switch (h->root.type)
546 default:
547 hsec = NULL;
548 break;
550 case bfd_link_hash_defined:
551 case bfd_link_hash_defweak:
552 hsec = h->root.u.def.section;
553 break;
555 case bfd_link_hash_common:
556 hsec = h->root.u.c.p->section;
557 break;
560 if (hsec == NULL)
561 olddyn = false;
562 else
563 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
566 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
567 respectively, appear to be a definition rather than reference. */
569 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
570 newdef = false;
571 else
572 newdef = true;
574 if (h->root.type == bfd_link_hash_undefined
575 || h->root.type == bfd_link_hash_undefweak
576 || h->root.type == bfd_link_hash_common)
577 olddef = false;
578 else
579 olddef = true;
581 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
582 symbol, respectively, appears to be a common symbol in a dynamic
583 object. If a symbol appears in an uninitialized section, and is
584 not weak, and is not a function, then it may be a common symbol
585 which was resolved when the dynamic object was created. We want
586 to treat such symbols specially, because they raise special
587 considerations when setting the symbol size: if the symbol
588 appears as a common symbol in a regular object, and the size in
589 the regular object is larger, we must make sure that we use the
590 larger size. This problematic case can always be avoided in C,
591 but it must be handled correctly when using Fortran shared
592 libraries.
594 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
595 likewise for OLDDYNCOMMON and OLDDEF.
597 Note that this test is just a heuristic, and that it is quite
598 possible to have an uninitialized symbol in a shared object which
599 is really a definition, rather than a common symbol. This could
600 lead to some minor confusion when the symbol really is a common
601 symbol in some regular object. However, I think it will be
602 harmless. */
604 if (newdyn
605 && newdef
606 && (sec->flags & SEC_ALLOC) != 0
607 && (sec->flags & SEC_LOAD) == 0
608 && sym->st_size > 0
609 && bind != STB_WEAK
610 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
611 newdyncommon = true;
612 else
613 newdyncommon = false;
615 if (olddyn
616 && olddef
617 && h->root.type == bfd_link_hash_defined
618 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
619 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
620 && (h->root.u.def.section->flags & SEC_LOAD) == 0
621 && h->size > 0
622 && h->type != STT_FUNC)
623 olddyncommon = true;
624 else
625 olddyncommon = false;
627 /* It's OK to change the type if either the existing symbol or the
628 new symbol is weak. */
630 if (h->root.type == bfd_link_hash_defweak
631 || h->root.type == bfd_link_hash_undefweak
632 || bind == STB_WEAK)
633 *type_change_ok = true;
635 /* It's OK to change the size if either the existing symbol or the
636 new symbol is weak, or if the old symbol is undefined. */
638 if (*type_change_ok
639 || h->root.type == bfd_link_hash_undefined)
640 *size_change_ok = true;
642 /* If both the old and the new symbols look like common symbols in a
643 dynamic object, set the size of the symbol to the larger of the
644 two. */
646 if (olddyncommon
647 && newdyncommon
648 && sym->st_size != h->size)
650 /* Since we think we have two common symbols, issue a multiple
651 common warning if desired. Note that we only warn if the
652 size is different. If the size is the same, we simply let
653 the old symbol override the new one as normally happens with
654 symbols defined in dynamic objects. */
656 if (! ((*info->callbacks->multiple_common)
657 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
658 h->size, abfd, bfd_link_hash_common, sym->st_size)))
659 return false;
661 if (sym->st_size > h->size)
662 h->size = sym->st_size;
664 *size_change_ok = true;
667 /* If we are looking at a dynamic object, and we have found a
668 definition, we need to see if the symbol was already defined by
669 some other object. If so, we want to use the existing
670 definition, and we do not want to report a multiple symbol
671 definition error; we do this by clobbering *PSEC to be
672 bfd_und_section_ptr.
674 We treat a common symbol as a definition if the symbol in the
675 shared library is a function, since common symbols always
676 represent variables; this can cause confusion in principle, but
677 any such confusion would seem to indicate an erroneous program or
678 shared library. We also permit a common symbol in a regular
679 object to override a weak symbol in a shared object.
681 We prefer a non-weak definition in a shared library to a weak
682 definition in the executable. */
684 if (newdyn
685 && newdef
686 && (olddef
687 || (h->root.type == bfd_link_hash_common
688 && (bind == STB_WEAK
689 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
690 && (h->root.type != bfd_link_hash_defweak
691 || bind == STB_WEAK))
693 *override = true;
694 newdef = false;
695 newdyncommon = false;
697 *psec = sec = bfd_und_section_ptr;
698 *size_change_ok = true;
700 /* If we get here when the old symbol is a common symbol, then
701 we are explicitly letting it override a weak symbol or
702 function in a dynamic object, and we don't want to warn about
703 a type change. If the old symbol is a defined symbol, a type
704 change warning may still be appropriate. */
706 if (h->root.type == bfd_link_hash_common)
707 *type_change_ok = true;
710 /* Handle the special case of an old common symbol merging with a
711 new symbol which looks like a common symbol in a shared object.
712 We change *PSEC and *PVALUE to make the new symbol look like a
713 common symbol, and let _bfd_generic_link_add_one_symbol will do
714 the right thing. */
716 if (newdyncommon
717 && h->root.type == bfd_link_hash_common)
719 *override = true;
720 newdef = false;
721 newdyncommon = false;
722 *pvalue = sym->st_size;
723 *psec = sec = bfd_com_section_ptr;
724 *size_change_ok = true;
727 /* If the old symbol is from a dynamic object, and the new symbol is
728 a definition which is not from a dynamic object, then the new
729 symbol overrides the old symbol. Symbols from regular files
730 always take precedence over symbols from dynamic objects, even if
731 they are defined after the dynamic object in the link.
733 As above, we again permit a common symbol in a regular object to
734 override a definition in a shared object if the shared object
735 symbol is a function or is weak.
737 As above, we permit a non-weak definition in a shared object to
738 override a weak definition in a regular object. */
740 if (! newdyn
741 && (newdef
742 || (bfd_is_com_section (sec)
743 && (h->root.type == bfd_link_hash_defweak
744 || h->type == STT_FUNC)))
745 && olddyn
746 && olddef
747 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
748 && (bind != STB_WEAK
749 || h->root.type == bfd_link_hash_defweak))
751 /* Change the hash table entry to undefined, and let
752 _bfd_generic_link_add_one_symbol do the right thing with the
753 new definition. */
755 h->root.type = bfd_link_hash_undefined;
756 h->root.u.undef.abfd = h->root.u.def.section->owner;
757 *size_change_ok = true;
759 olddef = false;
760 olddyncommon = false;
762 /* We again permit a type change when a common symbol may be
763 overriding a function. */
765 if (bfd_is_com_section (sec))
766 *type_change_ok = true;
768 /* This union may have been set to be non-NULL when this symbol
769 was seen in a dynamic object. We must force the union to be
770 NULL, so that it is correct for a regular symbol. */
772 h->verinfo.vertree = NULL;
774 /* In this special case, if H is the target of an indirection,
775 we want the caller to frob with H rather than with the
776 indirect symbol. That will permit the caller to redefine the
777 target of the indirection, rather than the indirect symbol
778 itself. FIXME: This will break the -y option if we store a
779 symbol with a different name. */
780 *sym_hash = h;
783 /* Handle the special case of a new common symbol merging with an
784 old symbol that looks like it might be a common symbol defined in
785 a shared object. Note that we have already handled the case in
786 which a new common symbol should simply override the definition
787 in the shared library. */
789 if (! newdyn
790 && bfd_is_com_section (sec)
791 && olddyncommon)
793 /* It would be best if we could set the hash table entry to a
794 common symbol, but we don't know what to use for the section
795 or the alignment. */
796 if (! ((*info->callbacks->multiple_common)
797 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
798 h->size, abfd, bfd_link_hash_common, sym->st_size)))
799 return false;
801 /* If the predumed common symbol in the dynamic object is
802 larger, pretend that the new symbol has its size. */
804 if (h->size > *pvalue)
805 *pvalue = h->size;
807 /* FIXME: We no longer know the alignment required by the symbol
808 in the dynamic object, so we just wind up using the one from
809 the regular object. */
811 olddef = false;
812 olddyncommon = false;
814 h->root.type = bfd_link_hash_undefined;
815 h->root.u.undef.abfd = h->root.u.def.section->owner;
817 *size_change_ok = true;
818 *type_change_ok = true;
820 h->verinfo.vertree = NULL;
823 /* Handle the special case of a weak definition in a regular object
824 followed by a non-weak definition in a shared object. In this
825 case, we prefer the definition in the shared object. */
826 if (olddef
827 && h->root.type == bfd_link_hash_defweak
828 && newdef
829 && newdyn
830 && bind != STB_WEAK)
832 /* To make this work we have to frob the flags so that the rest
833 of the code does not think we are using the regular
834 definition. */
835 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
836 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
837 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
838 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
839 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
840 | ELF_LINK_HASH_DEF_DYNAMIC);
842 /* If H is the target of an indirection, we want the caller to
843 use H rather than the indirect symbol. Otherwise if we are
844 defining a new indirect symbol we will wind up attaching it
845 to the entry we are overriding. */
846 *sym_hash = h;
849 /* Handle the special case of a non-weak definition in a shared
850 object followed by a weak definition in a regular object. In
851 this case we prefer to definition in the shared object. To make
852 this work we have to tell the caller to not treat the new symbol
853 as a definition. */
854 if (olddef
855 && olddyn
856 && h->root.type != bfd_link_hash_defweak
857 && newdef
858 && ! newdyn
859 && bind == STB_WEAK)
860 *override = true;
862 return true;
865 /* Add symbols from an ELF object file to the linker hash table. */
867 static boolean
868 elf_link_add_object_symbols (abfd, info)
869 bfd *abfd;
870 struct bfd_link_info *info;
872 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
873 const Elf_Internal_Sym *,
874 const char **, flagword *,
875 asection **, bfd_vma *));
876 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
877 asection *, const Elf_Internal_Rela *));
878 boolean collect;
879 Elf_Internal_Shdr *hdr;
880 size_t symcount;
881 size_t extsymcount;
882 size_t extsymoff;
883 Elf_External_Sym *buf = NULL;
884 struct elf_link_hash_entry **sym_hash;
885 boolean dynamic;
886 bfd_byte *dynver = NULL;
887 Elf_External_Versym *extversym = NULL;
888 Elf_External_Versym *ever;
889 Elf_External_Dyn *dynbuf = NULL;
890 struct elf_link_hash_entry *weaks;
891 Elf_External_Sym *esym;
892 Elf_External_Sym *esymend;
894 add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook;
895 collect = get_elf_backend_data (abfd)->collect;
897 if ((abfd->flags & DYNAMIC) == 0)
898 dynamic = false;
899 else
901 dynamic = true;
903 /* You can't use -r against a dynamic object. Also, there's no
904 hope of using a dynamic object which does not exactly match
905 the format of the output file. */
906 if (info->relocateable || info->hash->creator != abfd->xvec)
908 bfd_set_error (bfd_error_invalid_operation);
909 goto error_return;
913 /* As a GNU extension, any input sections which are named
914 .gnu.warning.SYMBOL are treated as warning symbols for the given
915 symbol. This differs from .gnu.warning sections, which generate
916 warnings when they are included in an output file. */
917 if (! info->shared)
919 asection *s;
921 for (s = abfd->sections; s != NULL; s = s->next)
923 const char *name;
925 name = bfd_get_section_name (abfd, s);
926 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
928 char *msg;
929 bfd_size_type sz;
931 name += sizeof ".gnu.warning." - 1;
933 /* If this is a shared object, then look up the symbol
934 in the hash table. If it is there, and it is already
935 been defined, then we will not be using the entry
936 from this shared object, so we don't need to warn.
937 FIXME: If we see the definition in a regular object
938 later on, we will warn, but we shouldn't. The only
939 fix is to keep track of what warnings we are supposed
940 to emit, and then handle them all at the end of the
941 link. */
942 if (dynamic && abfd->xvec == info->hash->creator)
944 struct elf_link_hash_entry *h;
946 h = elf_link_hash_lookup (elf_hash_table (info), name,
947 false, false, true);
949 /* FIXME: What about bfd_link_hash_common? */
950 if (h != NULL
951 && (h->root.type == bfd_link_hash_defined
952 || h->root.type == bfd_link_hash_defweak))
954 /* We don't want to issue this warning. Clobber
955 the section size so that the warning does not
956 get copied into the output file. */
957 s->_raw_size = 0;
958 continue;
962 sz = bfd_section_size (abfd, s);
963 msg = (char *) bfd_alloc (abfd, sz + 1);
964 if (msg == NULL)
965 goto error_return;
967 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
968 goto error_return;
970 msg[sz] = '\0';
972 if (! (_bfd_generic_link_add_one_symbol
973 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
974 false, collect, (struct bfd_link_hash_entry **) NULL)))
975 goto error_return;
977 if (! info->relocateable)
979 /* Clobber the section size so that the warning does
980 not get copied into the output file. */
981 s->_raw_size = 0;
987 /* If this is a dynamic object, we always link against the .dynsym
988 symbol table, not the .symtab symbol table. The dynamic linker
989 will only see the .dynsym symbol table, so there is no reason to
990 look at .symtab for a dynamic object. */
992 if (! dynamic || elf_dynsymtab (abfd) == 0)
993 hdr = &elf_tdata (abfd)->symtab_hdr;
994 else
995 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
997 if (dynamic)
999 /* Read in any version definitions. */
1001 if (! _bfd_elf_slurp_version_tables (abfd))
1002 goto error_return;
1004 /* Read in the symbol versions, but don't bother to convert them
1005 to internal format. */
1006 if (elf_dynversym (abfd) != 0)
1008 Elf_Internal_Shdr *versymhdr;
1010 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1011 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1012 if (extversym == NULL)
1013 goto error_return;
1014 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1015 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1016 != versymhdr->sh_size))
1017 goto error_return;
1021 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1023 /* The sh_info field of the symtab header tells us where the
1024 external symbols start. We don't care about the local symbols at
1025 this point. */
1026 if (elf_bad_symtab (abfd))
1028 extsymcount = symcount;
1029 extsymoff = 0;
1031 else
1033 extsymcount = symcount - hdr->sh_info;
1034 extsymoff = hdr->sh_info;
1037 buf = ((Elf_External_Sym *)
1038 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1039 if (buf == NULL && extsymcount != 0)
1040 goto error_return;
1042 /* We store a pointer to the hash table entry for each external
1043 symbol. */
1044 sym_hash = ((struct elf_link_hash_entry **)
1045 bfd_alloc (abfd,
1046 extsymcount * sizeof (struct elf_link_hash_entry *)));
1047 if (sym_hash == NULL)
1048 goto error_return;
1049 elf_sym_hashes (abfd) = sym_hash;
1051 if (! dynamic)
1053 /* If we are creating a shared library, create all the dynamic
1054 sections immediately. We need to attach them to something,
1055 so we attach them to this BFD, provided it is the right
1056 format. FIXME: If there are no input BFD's of the same
1057 format as the output, we can't make a shared library. */
1058 if (info->shared
1059 && ! elf_hash_table (info)->dynamic_sections_created
1060 && abfd->xvec == info->hash->creator)
1062 if (! elf_link_create_dynamic_sections (abfd, info))
1063 goto error_return;
1066 else
1068 asection *s;
1069 boolean add_needed;
1070 const char *name;
1071 bfd_size_type oldsize;
1072 bfd_size_type strindex;
1074 /* Find the name to use in a DT_NEEDED entry that refers to this
1075 object. If the object has a DT_SONAME entry, we use it.
1076 Otherwise, if the generic linker stuck something in
1077 elf_dt_name, we use that. Otherwise, we just use the file
1078 name. If the generic linker put a null string into
1079 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1080 there is a DT_SONAME entry. */
1081 add_needed = true;
1082 name = bfd_get_filename (abfd);
1083 if (elf_dt_name (abfd) != NULL)
1085 name = elf_dt_name (abfd);
1086 if (*name == '\0')
1087 add_needed = false;
1089 s = bfd_get_section_by_name (abfd, ".dynamic");
1090 if (s != NULL)
1092 Elf_External_Dyn *extdyn;
1093 Elf_External_Dyn *extdynend;
1094 int elfsec;
1095 unsigned long link;
1097 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1098 if (dynbuf == NULL)
1099 goto error_return;
1101 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1102 (file_ptr) 0, s->_raw_size))
1103 goto error_return;
1105 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1106 if (elfsec == -1)
1107 goto error_return;
1108 link = elf_elfsections (abfd)[elfsec]->sh_link;
1111 /* The shared libraries distributed with hpux11 have a bogus
1112 sh_link field for the ".dynamic" section. This code detects
1113 when LINK refers to a section that is not a string table and
1114 tries to find the string table for the ".dynsym" section
1115 instead. */
1116 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1117 if (hdr->sh_type != SHT_STRTAB)
1119 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1120 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1121 if (elfsec == -1)
1122 goto error_return;
1123 link = elf_elfsections (abfd)[elfsec]->sh_link;
1127 extdyn = dynbuf;
1128 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1129 for (; extdyn < extdynend; extdyn++)
1131 Elf_Internal_Dyn dyn;
1133 elf_swap_dyn_in (abfd, extdyn, &dyn);
1134 if (dyn.d_tag == DT_SONAME)
1136 name = bfd_elf_string_from_elf_section (abfd, link,
1137 dyn.d_un.d_val);
1138 if (name == NULL)
1139 goto error_return;
1141 if (dyn.d_tag == DT_NEEDED)
1143 struct bfd_link_needed_list *n, **pn;
1144 char *fnm, *anm;
1146 n = ((struct bfd_link_needed_list *)
1147 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1148 fnm = bfd_elf_string_from_elf_section (abfd, link,
1149 dyn.d_un.d_val);
1150 if (n == NULL || fnm == NULL)
1151 goto error_return;
1152 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1153 if (anm == NULL)
1154 goto error_return;
1155 strcpy (anm, fnm);
1156 n->name = anm;
1157 n->by = abfd;
1158 n->next = NULL;
1159 for (pn = &elf_hash_table (info)->needed;
1160 *pn != NULL;
1161 pn = &(*pn)->next)
1163 *pn = n;
1167 free (dynbuf);
1168 dynbuf = NULL;
1171 /* We do not want to include any of the sections in a dynamic
1172 object in the output file. We hack by simply clobbering the
1173 list of sections in the BFD. This could be handled more
1174 cleanly by, say, a new section flag; the existing
1175 SEC_NEVER_LOAD flag is not the one we want, because that one
1176 still implies that the section takes up space in the output
1177 file. */
1178 abfd->sections = NULL;
1179 abfd->section_count = 0;
1181 /* If this is the first dynamic object found in the link, create
1182 the special sections required for dynamic linking. */
1183 if (! elf_hash_table (info)->dynamic_sections_created)
1185 if (! elf_link_create_dynamic_sections (abfd, info))
1186 goto error_return;
1189 if (add_needed)
1191 /* Add a DT_NEEDED entry for this dynamic object. */
1192 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1193 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1194 true, false);
1195 if (strindex == (bfd_size_type) -1)
1196 goto error_return;
1198 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1200 asection *sdyn;
1201 Elf_External_Dyn *dyncon, *dynconend;
1203 /* The hash table size did not change, which means that
1204 the dynamic object name was already entered. If we
1205 have already included this dynamic object in the
1206 link, just ignore it. There is no reason to include
1207 a particular dynamic object more than once. */
1208 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1209 ".dynamic");
1210 BFD_ASSERT (sdyn != NULL);
1212 dyncon = (Elf_External_Dyn *) sdyn->contents;
1213 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1214 sdyn->_raw_size);
1215 for (; dyncon < dynconend; dyncon++)
1217 Elf_Internal_Dyn dyn;
1219 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1220 &dyn);
1221 if (dyn.d_tag == DT_NEEDED
1222 && dyn.d_un.d_val == strindex)
1224 if (buf != NULL)
1225 free (buf);
1226 if (extversym != NULL)
1227 free (extversym);
1228 return true;
1233 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1234 goto error_return;
1237 /* Save the SONAME, if there is one, because sometimes the
1238 linker emulation code will need to know it. */
1239 if (*name == '\0')
1240 name = bfd_get_filename (abfd);
1241 elf_dt_name (abfd) = name;
1244 if (bfd_seek (abfd,
1245 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1246 SEEK_SET) != 0
1247 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1248 != extsymcount * sizeof (Elf_External_Sym)))
1249 goto error_return;
1251 weaks = NULL;
1253 ever = extversym != NULL ? extversym + extsymoff : NULL;
1254 esymend = buf + extsymcount;
1255 for (esym = buf;
1256 esym < esymend;
1257 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1259 Elf_Internal_Sym sym;
1260 int bind;
1261 bfd_vma value;
1262 asection *sec;
1263 flagword flags;
1264 const char *name;
1265 struct elf_link_hash_entry *h;
1266 boolean definition;
1267 boolean size_change_ok, type_change_ok;
1268 boolean new_weakdef;
1269 unsigned int old_alignment;
1271 elf_swap_symbol_in (abfd, esym, &sym);
1273 flags = BSF_NO_FLAGS;
1274 sec = NULL;
1275 value = sym.st_value;
1276 *sym_hash = NULL;
1278 bind = ELF_ST_BIND (sym.st_info);
1279 if (bind == STB_LOCAL)
1281 /* This should be impossible, since ELF requires that all
1282 global symbols follow all local symbols, and that sh_info
1283 point to the first global symbol. Unfortunatealy, Irix 5
1284 screws this up. */
1285 continue;
1287 else if (bind == STB_GLOBAL)
1289 if (sym.st_shndx != SHN_UNDEF
1290 && sym.st_shndx != SHN_COMMON)
1291 flags = BSF_GLOBAL;
1292 else
1293 flags = 0;
1295 else if (bind == STB_WEAK)
1296 flags = BSF_WEAK;
1297 else
1299 /* Leave it up to the processor backend. */
1302 if (sym.st_shndx == SHN_UNDEF)
1303 sec = bfd_und_section_ptr;
1304 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1306 sec = section_from_elf_index (abfd, sym.st_shndx);
1307 if (sec == NULL)
1308 sec = bfd_abs_section_ptr;
1309 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1310 value -= sec->vma;
1312 else if (sym.st_shndx == SHN_ABS)
1313 sec = bfd_abs_section_ptr;
1314 else if (sym.st_shndx == SHN_COMMON)
1316 sec = bfd_com_section_ptr;
1317 /* What ELF calls the size we call the value. What ELF
1318 calls the value we call the alignment. */
1319 value = sym.st_size;
1321 else
1323 /* Leave it up to the processor backend. */
1326 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1327 if (name == (const char *) NULL)
1328 goto error_return;
1330 if (add_symbol_hook)
1332 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1333 &value))
1334 goto error_return;
1336 /* The hook function sets the name to NULL if this symbol
1337 should be skipped for some reason. */
1338 if (name == (const char *) NULL)
1339 continue;
1342 /* Sanity check that all possibilities were handled. */
1343 if (sec == (asection *) NULL)
1345 bfd_set_error (bfd_error_bad_value);
1346 goto error_return;
1349 if (bfd_is_und_section (sec)
1350 || bfd_is_com_section (sec))
1351 definition = false;
1352 else
1353 definition = true;
1355 size_change_ok = false;
1356 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1357 old_alignment = 0;
1358 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1360 Elf_Internal_Versym iver;
1361 unsigned int vernum = 0;
1362 boolean override;
1364 if (ever != NULL)
1366 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1367 vernum = iver.vs_vers & VERSYM_VERSION;
1369 /* If this is a hidden symbol, or if it is not version
1370 1, we append the version name to the symbol name.
1371 However, we do not modify a non-hidden absolute
1372 symbol, because it might be the version symbol
1373 itself. FIXME: What if it isn't? */
1374 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1375 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1377 const char *verstr;
1378 int namelen, newlen;
1379 char *newname, *p;
1381 if (sym.st_shndx != SHN_UNDEF)
1383 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1385 (*_bfd_error_handler)
1386 (_("%s: %s: invalid version %u (max %d)"),
1387 bfd_get_filename (abfd), name, vernum,
1388 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1389 bfd_set_error (bfd_error_bad_value);
1390 goto error_return;
1392 else if (vernum > 1)
1393 verstr =
1394 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1395 else
1396 verstr = "";
1398 else
1400 /* We cannot simply test for the number of
1401 entries in the VERNEED section since the
1402 numbers for the needed versions do not start
1403 at 0. */
1404 Elf_Internal_Verneed *t;
1406 verstr = NULL;
1407 for (t = elf_tdata (abfd)->verref;
1408 t != NULL;
1409 t = t->vn_nextref)
1411 Elf_Internal_Vernaux *a;
1413 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1415 if (a->vna_other == vernum)
1417 verstr = a->vna_nodename;
1418 break;
1421 if (a != NULL)
1422 break;
1424 if (verstr == NULL)
1426 (*_bfd_error_handler)
1427 (_("%s: %s: invalid needed version %d"),
1428 bfd_get_filename (abfd), name, vernum);
1429 bfd_set_error (bfd_error_bad_value);
1430 goto error_return;
1434 namelen = strlen (name);
1435 newlen = namelen + strlen (verstr) + 2;
1436 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1437 ++newlen;
1439 newname = (char *) bfd_alloc (abfd, newlen);
1440 if (newname == NULL)
1441 goto error_return;
1442 strcpy (newname, name);
1443 p = newname + namelen;
1444 *p++ = ELF_VER_CHR;
1445 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1446 *p++ = ELF_VER_CHR;
1447 strcpy (p, verstr);
1449 name = newname;
1453 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1454 sym_hash, &override, &type_change_ok,
1455 &size_change_ok))
1456 goto error_return;
1458 if (override)
1459 definition = false;
1461 h = *sym_hash;
1462 while (h->root.type == bfd_link_hash_indirect
1463 || h->root.type == bfd_link_hash_warning)
1464 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1466 /* Remember the old alignment if this is a common symbol, so
1467 that we don't reduce the alignment later on. We can't
1468 check later, because _bfd_generic_link_add_one_symbol
1469 will set a default for the alignment which we want to
1470 override. */
1471 if (h->root.type == bfd_link_hash_common)
1472 old_alignment = h->root.u.c.p->alignment_power;
1474 if (elf_tdata (abfd)->verdef != NULL
1475 && ! override
1476 && vernum > 1
1477 && definition)
1478 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1481 if (! (_bfd_generic_link_add_one_symbol
1482 (info, abfd, name, flags, sec, value, (const char *) NULL,
1483 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1484 goto error_return;
1486 h = *sym_hash;
1487 while (h->root.type == bfd_link_hash_indirect
1488 || h->root.type == bfd_link_hash_warning)
1489 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1490 *sym_hash = h;
1492 new_weakdef = false;
1493 if (dynamic
1494 && definition
1495 && (flags & BSF_WEAK) != 0
1496 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1497 && info->hash->creator->flavour == bfd_target_elf_flavour
1498 && h->weakdef == NULL)
1500 /* Keep a list of all weak defined non function symbols from
1501 a dynamic object, using the weakdef field. Later in this
1502 function we will set the weakdef field to the correct
1503 value. We only put non-function symbols from dynamic
1504 objects on this list, because that happens to be the only
1505 time we need to know the normal symbol corresponding to a
1506 weak symbol, and the information is time consuming to
1507 figure out. If the weakdef field is not already NULL,
1508 then this symbol was already defined by some previous
1509 dynamic object, and we will be using that previous
1510 definition anyhow. */
1512 h->weakdef = weaks;
1513 weaks = h;
1514 new_weakdef = true;
1517 /* Set the alignment of a common symbol. */
1518 if (sym.st_shndx == SHN_COMMON
1519 && h->root.type == bfd_link_hash_common)
1521 unsigned int align;
1523 align = bfd_log2 (sym.st_value);
1524 if (align > old_alignment)
1525 h->root.u.c.p->alignment_power = align;
1528 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1530 int old_flags;
1531 boolean dynsym;
1532 int new_flag;
1534 /* Remember the symbol size and type. */
1535 if (sym.st_size != 0
1536 && (definition || h->size == 0))
1538 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1539 (*_bfd_error_handler)
1540 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1541 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1542 bfd_get_filename (abfd));
1544 h->size = sym.st_size;
1547 /* If this is a common symbol, then we always want H->SIZE
1548 to be the size of the common symbol. The code just above
1549 won't fix the size if a common symbol becomes larger. We
1550 don't warn about a size change here, because that is
1551 covered by --warn-common. */
1552 if (h->root.type == bfd_link_hash_common)
1553 h->size = h->root.u.c.size;
1555 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1556 && (definition || h->type == STT_NOTYPE))
1558 if (h->type != STT_NOTYPE
1559 && h->type != ELF_ST_TYPE (sym.st_info)
1560 && ! type_change_ok)
1561 (*_bfd_error_handler)
1562 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1563 name, h->type, ELF_ST_TYPE (sym.st_info),
1564 bfd_get_filename (abfd));
1566 h->type = ELF_ST_TYPE (sym.st_info);
1569 if (sym.st_other != 0
1570 && (definition || h->other == 0))
1571 h->other = sym.st_other;
1573 /* Set a flag in the hash table entry indicating the type of
1574 reference or definition we just found. Keep a count of
1575 the number of dynamic symbols we find. A dynamic symbol
1576 is one which is referenced or defined by both a regular
1577 object and a shared object. */
1578 old_flags = h->elf_link_hash_flags;
1579 dynsym = false;
1580 if (! dynamic)
1582 if (! definition)
1584 new_flag = ELF_LINK_HASH_REF_REGULAR;
1585 if (bind != STB_WEAK)
1586 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1588 else
1589 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1590 if (info->shared
1591 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1592 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1593 dynsym = true;
1595 else
1597 if (! definition)
1598 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1599 else
1600 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1601 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1602 | ELF_LINK_HASH_REF_REGULAR)) != 0
1603 || (h->weakdef != NULL
1604 && ! new_weakdef
1605 && h->weakdef->dynindx != -1))
1606 dynsym = true;
1609 h->elf_link_hash_flags |= new_flag;
1611 /* If this symbol has a version, and it is the default
1612 version, we create an indirect symbol from the default
1613 name to the fully decorated name. This will cause
1614 external references which do not specify a version to be
1615 bound to this version of the symbol. */
1616 if (definition)
1618 char *p;
1620 p = strchr (name, ELF_VER_CHR);
1621 if (p != NULL && p[1] == ELF_VER_CHR)
1623 char *shortname;
1624 struct elf_link_hash_entry *hi;
1625 boolean override;
1627 shortname = bfd_hash_allocate (&info->hash->table,
1628 p - name + 1);
1629 if (shortname == NULL)
1630 goto error_return;
1631 strncpy (shortname, name, p - name);
1632 shortname[p - name] = '\0';
1634 /* We are going to create a new symbol. Merge it
1635 with any existing symbol with this name. For the
1636 purposes of the merge, act as though we were
1637 defining the symbol we just defined, although we
1638 actually going to define an indirect symbol. */
1639 type_change_ok = false;
1640 size_change_ok = false;
1641 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1642 &value, &hi, &override,
1643 &type_change_ok, &size_change_ok))
1644 goto error_return;
1646 if (! override)
1648 if (! (_bfd_generic_link_add_one_symbol
1649 (info, abfd, shortname, BSF_INDIRECT,
1650 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1651 collect, (struct bfd_link_hash_entry **) &hi)))
1652 goto error_return;
1654 else
1656 /* In this case the symbol named SHORTNAME is
1657 overriding the indirect symbol we want to
1658 add. We were planning on making SHORTNAME an
1659 indirect symbol referring to NAME. SHORTNAME
1660 is the name without a version. NAME is the
1661 fully versioned name, and it is the default
1662 version.
1664 Overriding means that we already saw a
1665 definition for the symbol SHORTNAME in a
1666 regular object, and it is overriding the
1667 symbol defined in the dynamic object.
1669 When this happens, we actually want to change
1670 NAME, the symbol we just added, to refer to
1671 SHORTNAME. This will cause references to
1672 NAME in the shared object to become
1673 references to SHORTNAME in the regular
1674 object. This is what we expect when we
1675 override a function in a shared object: that
1676 the references in the shared object will be
1677 mapped to the definition in the regular
1678 object. */
1680 while (hi->root.type == bfd_link_hash_indirect
1681 || hi->root.type == bfd_link_hash_warning)
1682 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1684 h->root.type = bfd_link_hash_indirect;
1685 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1686 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1688 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1689 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1690 if (hi->elf_link_hash_flags
1691 & (ELF_LINK_HASH_REF_REGULAR
1692 | ELF_LINK_HASH_DEF_REGULAR))
1694 if (! _bfd_elf_link_record_dynamic_symbol (info,
1695 hi))
1696 goto error_return;
1700 /* Now set HI to H, so that the following code
1701 will set the other fields correctly. */
1702 hi = h;
1705 /* If there is a duplicate definition somewhere,
1706 then HI may not point to an indirect symbol. We
1707 will have reported an error to the user in that
1708 case. */
1710 if (hi->root.type == bfd_link_hash_indirect)
1712 struct elf_link_hash_entry *ht;
1714 /* If the symbol became indirect, then we assume
1715 that we have not seen a definition before. */
1716 BFD_ASSERT ((hi->elf_link_hash_flags
1717 & (ELF_LINK_HASH_DEF_DYNAMIC
1718 | ELF_LINK_HASH_DEF_REGULAR))
1719 == 0);
1721 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1723 /* Copy down any references that we may have
1724 already seen to the symbol which just became
1725 indirect. */
1726 ht->elf_link_hash_flags |=
1727 (hi->elf_link_hash_flags
1728 & (ELF_LINK_HASH_REF_DYNAMIC
1729 | ELF_LINK_HASH_REF_REGULAR
1730 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
1731 | ELF_LINK_NON_GOT_REF));
1733 /* Copy over the global and procedure linkage table
1734 offset entries. These may have been already set
1735 up by a check_relocs routine. */
1736 if (ht->got.offset == (bfd_vma) -1)
1738 ht->got.offset = hi->got.offset;
1739 hi->got.offset = (bfd_vma) -1;
1741 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1743 if (ht->plt.offset == (bfd_vma) -1)
1745 ht->plt.offset = hi->plt.offset;
1746 hi->plt.offset = (bfd_vma) -1;
1748 BFD_ASSERT (hi->plt.offset == (bfd_vma) -1);
1750 if (ht->dynindx == -1)
1752 ht->dynindx = hi->dynindx;
1753 ht->dynstr_index = hi->dynstr_index;
1754 hi->dynindx = -1;
1755 hi->dynstr_index = 0;
1757 BFD_ASSERT (hi->dynindx == -1);
1759 /* FIXME: There may be other information to copy
1760 over for particular targets. */
1762 /* See if the new flags lead us to realize that
1763 the symbol must be dynamic. */
1764 if (! dynsym)
1766 if (! dynamic)
1768 if (info->shared
1769 || ((hi->elf_link_hash_flags
1770 & ELF_LINK_HASH_REF_DYNAMIC)
1771 != 0))
1772 dynsym = true;
1774 else
1776 if ((hi->elf_link_hash_flags
1777 & ELF_LINK_HASH_REF_REGULAR) != 0)
1778 dynsym = true;
1783 /* We also need to define an indirection from the
1784 nondefault version of the symbol. */
1786 shortname = bfd_hash_allocate (&info->hash->table,
1787 strlen (name));
1788 if (shortname == NULL)
1789 goto error_return;
1790 strncpy (shortname, name, p - name);
1791 strcpy (shortname + (p - name), p + 1);
1793 /* Once again, merge with any existing symbol. */
1794 type_change_ok = false;
1795 size_change_ok = false;
1796 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1797 &value, &hi, &override,
1798 &type_change_ok, &size_change_ok))
1799 goto error_return;
1801 if (override)
1803 /* Here SHORTNAME is a versioned name, so we
1804 don't expect to see the type of override we
1805 do in the case above. */
1806 (*_bfd_error_handler)
1807 (_("%s: warning: unexpected redefinition of `%s'"),
1808 bfd_get_filename (abfd), shortname);
1810 else
1812 if (! (_bfd_generic_link_add_one_symbol
1813 (info, abfd, shortname, BSF_INDIRECT,
1814 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1815 collect, (struct bfd_link_hash_entry **) &hi)))
1816 goto error_return;
1818 /* If there is a duplicate definition somewhere,
1819 then HI may not point to an indirect symbol.
1820 We will have reported an error to the user in
1821 that case. */
1823 if (hi->root.type == bfd_link_hash_indirect)
1825 /* If the symbol became indirect, then we
1826 assume that we have not seen a definition
1827 before. */
1828 BFD_ASSERT ((hi->elf_link_hash_flags
1829 & (ELF_LINK_HASH_DEF_DYNAMIC
1830 | ELF_LINK_HASH_DEF_REGULAR))
1831 == 0);
1833 /* Copy down any references that we may have
1834 already seen to the symbol which just
1835 became indirect. */
1836 h->elf_link_hash_flags |=
1837 (hi->elf_link_hash_flags
1838 & (ELF_LINK_HASH_REF_DYNAMIC
1839 | ELF_LINK_HASH_REF_REGULAR
1840 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
1841 | ELF_LINK_NON_GOT_REF));
1843 /* Copy over the global and procedure linkage
1844 table offset entries. These may have been
1845 already set up by a check_relocs routine. */
1846 if (h->got.offset == (bfd_vma) -1)
1848 h->got.offset = hi->got.offset;
1849 hi->got.offset = (bfd_vma) -1;
1851 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1853 if (h->plt.offset == (bfd_vma) -1)
1855 h->plt.offset = hi->plt.offset;
1856 hi->plt.offset = (bfd_vma) -1;
1858 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1860 if (h->dynindx == -1)
1862 h->dynindx = hi->dynindx;
1863 h->dynstr_index = hi->dynstr_index;
1864 hi->dynindx = -1;
1865 hi->dynstr_index = 0;
1867 BFD_ASSERT (hi->dynindx == -1);
1869 /* FIXME: There may be other information to
1870 copy over for particular targets. */
1872 /* See if the new flags lead us to realize
1873 that the symbol must be dynamic. */
1874 if (! dynsym)
1876 if (! dynamic)
1878 if (info->shared
1879 || ((hi->elf_link_hash_flags
1880 & ELF_LINK_HASH_REF_DYNAMIC)
1881 != 0))
1882 dynsym = true;
1884 else
1886 if ((hi->elf_link_hash_flags
1887 & ELF_LINK_HASH_REF_REGULAR) != 0)
1888 dynsym = true;
1896 if (dynsym && h->dynindx == -1)
1898 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1899 goto error_return;
1900 if (h->weakdef != NULL
1901 && ! new_weakdef
1902 && h->weakdef->dynindx == -1)
1904 if (! _bfd_elf_link_record_dynamic_symbol (info,
1905 h->weakdef))
1906 goto error_return;
1912 /* Now set the weakdefs field correctly for all the weak defined
1913 symbols we found. The only way to do this is to search all the
1914 symbols. Since we only need the information for non functions in
1915 dynamic objects, that's the only time we actually put anything on
1916 the list WEAKS. We need this information so that if a regular
1917 object refers to a symbol defined weakly in a dynamic object, the
1918 real symbol in the dynamic object is also put in the dynamic
1919 symbols; we also must arrange for both symbols to point to the
1920 same memory location. We could handle the general case of symbol
1921 aliasing, but a general symbol alias can only be generated in
1922 assembler code, handling it correctly would be very time
1923 consuming, and other ELF linkers don't handle general aliasing
1924 either. */
1925 while (weaks != NULL)
1927 struct elf_link_hash_entry *hlook;
1928 asection *slook;
1929 bfd_vma vlook;
1930 struct elf_link_hash_entry **hpp;
1931 struct elf_link_hash_entry **hppend;
1933 hlook = weaks;
1934 weaks = hlook->weakdef;
1935 hlook->weakdef = NULL;
1937 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1938 || hlook->root.type == bfd_link_hash_defweak
1939 || hlook->root.type == bfd_link_hash_common
1940 || hlook->root.type == bfd_link_hash_indirect);
1941 slook = hlook->root.u.def.section;
1942 vlook = hlook->root.u.def.value;
1944 hpp = elf_sym_hashes (abfd);
1945 hppend = hpp + extsymcount;
1946 for (; hpp < hppend; hpp++)
1948 struct elf_link_hash_entry *h;
1950 h = *hpp;
1951 if (h != NULL && h != hlook
1952 && h->root.type == bfd_link_hash_defined
1953 && h->root.u.def.section == slook
1954 && h->root.u.def.value == vlook)
1956 hlook->weakdef = h;
1958 /* If the weak definition is in the list of dynamic
1959 symbols, make sure the real definition is put there
1960 as well. */
1961 if (hlook->dynindx != -1
1962 && h->dynindx == -1)
1964 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1965 goto error_return;
1968 /* If the real definition is in the list of dynamic
1969 symbols, make sure the weak definition is put there
1970 as well. If we don't do this, then the dynamic
1971 loader might not merge the entries for the real
1972 definition and the weak definition. */
1973 if (h->dynindx != -1
1974 && hlook->dynindx == -1)
1976 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1977 goto error_return;
1980 break;
1985 if (buf != NULL)
1987 free (buf);
1988 buf = NULL;
1991 if (extversym != NULL)
1993 free (extversym);
1994 extversym = NULL;
1997 /* If this object is the same format as the output object, and it is
1998 not a shared library, then let the backend look through the
1999 relocs.
2001 This is required to build global offset table entries and to
2002 arrange for dynamic relocs. It is not required for the
2003 particular common case of linking non PIC code, even when linking
2004 against shared libraries, but unfortunately there is no way of
2005 knowing whether an object file has been compiled PIC or not.
2006 Looking through the relocs is not particularly time consuming.
2007 The problem is that we must either (1) keep the relocs in memory,
2008 which causes the linker to require additional runtime memory or
2009 (2) read the relocs twice from the input file, which wastes time.
2010 This would be a good case for using mmap.
2012 I have no idea how to handle linking PIC code into a file of a
2013 different format. It probably can't be done. */
2014 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2015 if (! dynamic
2016 && abfd->xvec == info->hash->creator
2017 && check_relocs != NULL)
2019 asection *o;
2021 for (o = abfd->sections; o != NULL; o = o->next)
2023 Elf_Internal_Rela *internal_relocs;
2024 boolean ok;
2026 if ((o->flags & SEC_RELOC) == 0
2027 || o->reloc_count == 0
2028 || ((info->strip == strip_all || info->strip == strip_debugger)
2029 && (o->flags & SEC_DEBUGGING) != 0)
2030 || bfd_is_abs_section (o->output_section))
2031 continue;
2033 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2034 (abfd, o, (PTR) NULL,
2035 (Elf_Internal_Rela *) NULL,
2036 info->keep_memory));
2037 if (internal_relocs == NULL)
2038 goto error_return;
2040 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2042 if (! info->keep_memory)
2043 free (internal_relocs);
2045 if (! ok)
2046 goto error_return;
2050 /* If this is a non-traditional, non-relocateable link, try to
2051 optimize the handling of the .stab/.stabstr sections. */
2052 if (! dynamic
2053 && ! info->relocateable
2054 && ! info->traditional_format
2055 && info->hash->creator->flavour == bfd_target_elf_flavour
2056 && (info->strip != strip_all && info->strip != strip_debugger))
2058 asection *stab, *stabstr;
2060 stab = bfd_get_section_by_name (abfd, ".stab");
2061 if (stab != NULL)
2063 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2065 if (stabstr != NULL)
2067 struct bfd_elf_section_data *secdata;
2069 secdata = elf_section_data (stab);
2070 if (! _bfd_link_section_stabs (abfd,
2071 &elf_hash_table (info)->stab_info,
2072 stab, stabstr,
2073 &secdata->stab_info))
2074 goto error_return;
2079 return true;
2081 error_return:
2082 if (buf != NULL)
2083 free (buf);
2084 if (dynbuf != NULL)
2085 free (dynbuf);
2086 if (dynver != NULL)
2087 free (dynver);
2088 if (extversym != NULL)
2089 free (extversym);
2090 return false;
2093 /* Create some sections which will be filled in with dynamic linking
2094 information. ABFD is an input file which requires dynamic sections
2095 to be created. The dynamic sections take up virtual memory space
2096 when the final executable is run, so we need to create them before
2097 addresses are assigned to the output sections. We work out the
2098 actual contents and size of these sections later. */
2100 boolean
2101 elf_link_create_dynamic_sections (abfd, info)
2102 bfd *abfd;
2103 struct bfd_link_info *info;
2105 flagword flags;
2106 register asection *s;
2107 struct elf_link_hash_entry *h;
2108 struct elf_backend_data *bed;
2110 if (elf_hash_table (info)->dynamic_sections_created)
2111 return true;
2113 /* Make sure that all dynamic sections use the same input BFD. */
2114 if (elf_hash_table (info)->dynobj == NULL)
2115 elf_hash_table (info)->dynobj = abfd;
2116 else
2117 abfd = elf_hash_table (info)->dynobj;
2119 /* Note that we set the SEC_IN_MEMORY flag for all of these
2120 sections. */
2121 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2122 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2124 /* A dynamically linked executable has a .interp section, but a
2125 shared library does not. */
2126 if (! info->shared)
2128 s = bfd_make_section (abfd, ".interp");
2129 if (s == NULL
2130 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2131 return false;
2134 /* Create sections to hold version informations. These are removed
2135 if they are not needed. */
2136 s = bfd_make_section (abfd, ".gnu.version_d");
2137 if (s == NULL
2138 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2139 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2140 return false;
2142 s = bfd_make_section (abfd, ".gnu.version");
2143 if (s == NULL
2144 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2145 || ! bfd_set_section_alignment (abfd, s, 1))
2146 return false;
2148 s = bfd_make_section (abfd, ".gnu.version_r");
2149 if (s == NULL
2150 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2151 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2152 return false;
2154 s = bfd_make_section (abfd, ".dynsym");
2155 if (s == NULL
2156 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2157 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2158 return false;
2160 s = bfd_make_section (abfd, ".dynstr");
2161 if (s == NULL
2162 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2163 return false;
2165 /* Create a strtab to hold the dynamic symbol names. */
2166 if (elf_hash_table (info)->dynstr == NULL)
2168 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2169 if (elf_hash_table (info)->dynstr == NULL)
2170 return false;
2173 s = bfd_make_section (abfd, ".dynamic");
2174 if (s == NULL
2175 || ! bfd_set_section_flags (abfd, s, flags)
2176 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2177 return false;
2179 /* The special symbol _DYNAMIC is always set to the start of the
2180 .dynamic section. This call occurs before we have processed the
2181 symbols for any dynamic object, so we don't have to worry about
2182 overriding a dynamic definition. We could set _DYNAMIC in a
2183 linker script, but we only want to define it if we are, in fact,
2184 creating a .dynamic section. We don't want to define it if there
2185 is no .dynamic section, since on some ELF platforms the start up
2186 code examines it to decide how to initialize the process. */
2187 h = NULL;
2188 if (! (_bfd_generic_link_add_one_symbol
2189 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2190 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2191 (struct bfd_link_hash_entry **) &h)))
2192 return false;
2193 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2194 h->type = STT_OBJECT;
2196 if (info->shared
2197 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2198 return false;
2200 bed = get_elf_backend_data (abfd);
2202 s = bfd_make_section (abfd, ".hash");
2203 if (s == NULL
2204 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2205 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2206 return false;
2207 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2209 /* Let the backend create the rest of the sections. This lets the
2210 backend set the right flags. The backend will normally create
2211 the .got and .plt sections. */
2212 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2213 return false;
2215 elf_hash_table (info)->dynamic_sections_created = true;
2217 return true;
2220 /* Add an entry to the .dynamic table. */
2222 boolean
2223 elf_add_dynamic_entry (info, tag, val)
2224 struct bfd_link_info *info;
2225 bfd_vma tag;
2226 bfd_vma val;
2228 Elf_Internal_Dyn dyn;
2229 bfd *dynobj;
2230 asection *s;
2231 size_t newsize;
2232 bfd_byte *newcontents;
2234 dynobj = elf_hash_table (info)->dynobj;
2236 s = bfd_get_section_by_name (dynobj, ".dynamic");
2237 BFD_ASSERT (s != NULL);
2239 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2240 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2241 if (newcontents == NULL)
2242 return false;
2244 dyn.d_tag = tag;
2245 dyn.d_un.d_val = val;
2246 elf_swap_dyn_out (dynobj, &dyn,
2247 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2249 s->_raw_size = newsize;
2250 s->contents = newcontents;
2252 return true;
2255 /* Record a new local dynamic symbol. */
2257 boolean
2258 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2259 struct bfd_link_info *info;
2260 bfd *input_bfd;
2261 long input_indx;
2263 struct elf_link_local_dynamic_entry *entry;
2264 struct elf_link_hash_table *eht;
2265 struct bfd_strtab_hash *dynstr;
2266 Elf_External_Sym esym;
2267 unsigned long dynstr_index;
2268 char *name;
2270 /* See if the entry exists already. */
2271 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2272 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2273 return true;
2275 entry = (struct elf_link_local_dynamic_entry *)
2276 bfd_alloc (input_bfd, sizeof (*entry));
2277 if (entry == NULL)
2278 return false;
2280 /* Go find the symbol, so that we can find it's name. */
2281 if (bfd_seek (input_bfd,
2282 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2283 + input_indx * sizeof (Elf_External_Sym)),
2284 SEEK_SET) != 0
2285 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2286 != sizeof (Elf_External_Sym)))
2287 return false;
2288 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2290 name = (bfd_elf_string_from_elf_section
2291 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2292 entry->isym.st_name));
2294 dynstr = elf_hash_table (info)->dynstr;
2295 if (dynstr == NULL)
2297 /* Create a strtab to hold the dynamic symbol names. */
2298 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2299 if (dynstr == NULL)
2300 return false;
2303 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2304 if (dynstr_index == (unsigned long) -1)
2305 return false;
2306 entry->isym.st_name = dynstr_index;
2308 eht = elf_hash_table (info);
2310 entry->next = eht->dynlocal;
2311 eht->dynlocal = entry;
2312 entry->input_bfd = input_bfd;
2313 entry->input_indx = input_indx;
2314 eht->dynsymcount++;
2316 /* Whatever binding the symbol had before, it's now local. */
2317 entry->isym.st_info
2318 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2320 /* The dynindx will be set at the end of size_dynamic_sections. */
2322 return true;
2326 /* Read and swap the relocs from the section indicated by SHDR. This
2327 may be either a REL or a RELA section. The relocations are
2328 translated into RELA relocations and stored in INTERNAL_RELOCS,
2329 which should have already been allocated to contain enough space.
2330 The EXTERNAL_RELOCS are a buffer where the external form of the
2331 relocations should be stored.
2333 Returns false if something goes wrong. */
2335 static boolean
2336 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2337 internal_relocs)
2338 bfd *abfd;
2339 Elf_Internal_Shdr *shdr;
2340 PTR external_relocs;
2341 Elf_Internal_Rela *internal_relocs;
2343 struct elf_backend_data *bed;
2345 /* If there aren't any relocations, that's OK. */
2346 if (!shdr)
2347 return true;
2349 /* Position ourselves at the start of the section. */
2350 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2351 return false;
2353 /* Read the relocations. */
2354 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2355 != shdr->sh_size)
2356 return false;
2358 bed = get_elf_backend_data (abfd);
2360 /* Convert the external relocations to the internal format. */
2361 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2363 Elf_External_Rel *erel;
2364 Elf_External_Rel *erelend;
2365 Elf_Internal_Rela *irela;
2366 Elf_Internal_Rel *irel;
2368 erel = (Elf_External_Rel *) external_relocs;
2369 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2370 irela = internal_relocs;
2371 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2372 * sizeof (Elf_Internal_Rel)));
2373 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2375 unsigned char i;
2377 if (bed->s->swap_reloc_in)
2378 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2379 else
2380 elf_swap_reloc_in (abfd, erel, irel);
2382 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2384 irela[i].r_offset = irel[i].r_offset;
2385 irela[i].r_info = irel[i].r_info;
2386 irela[i].r_addend = 0;
2390 else
2392 Elf_External_Rela *erela;
2393 Elf_External_Rela *erelaend;
2394 Elf_Internal_Rela *irela;
2396 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2398 erela = (Elf_External_Rela *) external_relocs;
2399 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2400 irela = internal_relocs;
2401 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2403 if (bed->s->swap_reloca_in)
2404 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2405 else
2406 elf_swap_reloca_in (abfd, erela, irela);
2410 return true;
2413 /* Read and swap the relocs for a section O. They may have been
2414 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2415 not NULL, they are used as buffers to read into. They are known to
2416 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2417 the return value is allocated using either malloc or bfd_alloc,
2418 according to the KEEP_MEMORY argument. If O has two relocation
2419 sections (both REL and RELA relocations), then the REL_HDR
2420 relocations will appear first in INTERNAL_RELOCS, followed by the
2421 REL_HDR2 relocations. */
2423 Elf_Internal_Rela *
2424 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2425 keep_memory)
2426 bfd *abfd;
2427 asection *o;
2428 PTR external_relocs;
2429 Elf_Internal_Rela *internal_relocs;
2430 boolean keep_memory;
2432 Elf_Internal_Shdr *rel_hdr;
2433 PTR alloc1 = NULL;
2434 Elf_Internal_Rela *alloc2 = NULL;
2435 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2437 if (elf_section_data (o)->relocs != NULL)
2438 return elf_section_data (o)->relocs;
2440 if (o->reloc_count == 0)
2441 return NULL;
2443 rel_hdr = &elf_section_data (o)->rel_hdr;
2445 if (internal_relocs == NULL)
2447 size_t size;
2449 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2450 * sizeof (Elf_Internal_Rela));
2451 if (keep_memory)
2452 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2453 else
2454 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2455 if (internal_relocs == NULL)
2456 goto error_return;
2459 if (external_relocs == NULL)
2461 size_t size = (size_t) rel_hdr->sh_size;
2463 if (elf_section_data (o)->rel_hdr2)
2464 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2465 alloc1 = (PTR) bfd_malloc (size);
2466 if (alloc1 == NULL)
2467 goto error_return;
2468 external_relocs = alloc1;
2471 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2472 external_relocs,
2473 internal_relocs))
2474 goto error_return;
2475 if (!elf_link_read_relocs_from_section
2476 (abfd,
2477 elf_section_data (o)->rel_hdr2,
2478 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2479 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2480 * bed->s->int_rels_per_ext_rel)))
2481 goto error_return;
2483 /* Cache the results for next time, if we can. */
2484 if (keep_memory)
2485 elf_section_data (o)->relocs = internal_relocs;
2487 if (alloc1 != NULL)
2488 free (alloc1);
2490 /* Don't free alloc2, since if it was allocated we are passing it
2491 back (under the name of internal_relocs). */
2493 return internal_relocs;
2495 error_return:
2496 if (alloc1 != NULL)
2497 free (alloc1);
2498 if (alloc2 != NULL)
2499 free (alloc2);
2500 return NULL;
2504 /* Record an assignment to a symbol made by a linker script. We need
2505 this in case some dynamic object refers to this symbol. */
2507 /*ARGSUSED*/
2508 boolean
2509 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2510 bfd *output_bfd ATTRIBUTE_UNUSED;
2511 struct bfd_link_info *info;
2512 const char *name;
2513 boolean provide;
2515 struct elf_link_hash_entry *h;
2517 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2518 return true;
2520 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2521 if (h == NULL)
2522 return false;
2524 if (h->root.type == bfd_link_hash_new)
2525 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2527 /* If this symbol is being provided by the linker script, and it is
2528 currently defined by a dynamic object, but not by a regular
2529 object, then mark it as undefined so that the generic linker will
2530 force the correct value. */
2531 if (provide
2532 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2533 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2534 h->root.type = bfd_link_hash_undefined;
2536 /* If this symbol is not being provided by the linker script, and it is
2537 currently defined by a dynamic object, but not by a regular object,
2538 then clear out any version information because the symbol will not be
2539 associated with the dynamic object any more. */
2540 if (!provide
2541 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2542 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2543 h->verinfo.verdef = NULL;
2545 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2547 /* When possible, keep the original type of the symbol */
2548 if (h->type == STT_NOTYPE)
2549 h->type = STT_OBJECT;
2551 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2552 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2553 || info->shared)
2554 && h->dynindx == -1)
2556 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2557 return false;
2559 /* If this is a weak defined symbol, and we know a corresponding
2560 real symbol from the same dynamic object, make sure the real
2561 symbol is also made into a dynamic symbol. */
2562 if (h->weakdef != NULL
2563 && h->weakdef->dynindx == -1)
2565 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2566 return false;
2570 return true;
2573 /* This structure is used to pass information to
2574 elf_link_assign_sym_version. */
2576 struct elf_assign_sym_version_info
2578 /* Output BFD. */
2579 bfd *output_bfd;
2580 /* General link information. */
2581 struct bfd_link_info *info;
2582 /* Version tree. */
2583 struct bfd_elf_version_tree *verdefs;
2584 /* Whether we are exporting all dynamic symbols. */
2585 boolean export_dynamic;
2586 /* Whether we had a failure. */
2587 boolean failed;
2590 /* This structure is used to pass information to
2591 elf_link_find_version_dependencies. */
2593 struct elf_find_verdep_info
2595 /* Output BFD. */
2596 bfd *output_bfd;
2597 /* General link information. */
2598 struct bfd_link_info *info;
2599 /* The number of dependencies. */
2600 unsigned int vers;
2601 /* Whether we had a failure. */
2602 boolean failed;
2605 /* Array used to determine the number of hash table buckets to use
2606 based on the number of symbols there are. If there are fewer than
2607 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2608 fewer than 37 we use 17 buckets, and so forth. We never use more
2609 than 32771 buckets. */
2611 static const size_t elf_buckets[] =
2613 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2614 16411, 32771, 0
2617 /* Compute bucket count for hashing table. We do not use a static set
2618 of possible tables sizes anymore. Instead we determine for all
2619 possible reasonable sizes of the table the outcome (i.e., the
2620 number of collisions etc) and choose the best solution. The
2621 weighting functions are not too simple to allow the table to grow
2622 without bounds. Instead one of the weighting factors is the size.
2623 Therefore the result is always a good payoff between few collisions
2624 (= short chain lengths) and table size. */
2625 static size_t
2626 compute_bucket_count (info)
2627 struct bfd_link_info *info;
2629 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2630 size_t best_size = 0;
2631 unsigned long int *hashcodes;
2632 unsigned long int *hashcodesp;
2633 unsigned long int i;
2635 /* Compute the hash values for all exported symbols. At the same
2636 time store the values in an array so that we could use them for
2637 optimizations. */
2638 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2639 * sizeof (unsigned long int));
2640 if (hashcodes == NULL)
2641 return 0;
2642 hashcodesp = hashcodes;
2644 /* Put all hash values in HASHCODES. */
2645 elf_link_hash_traverse (elf_hash_table (info),
2646 elf_collect_hash_codes, &hashcodesp);
2648 /* We have a problem here. The following code to optimize the table
2649 size requires an integer type with more the 32 bits. If
2650 BFD_HOST_U_64_BIT is set we know about such a type. */
2651 #ifdef BFD_HOST_U_64_BIT
2652 if (info->optimize == true)
2654 unsigned long int nsyms = hashcodesp - hashcodes;
2655 size_t minsize;
2656 size_t maxsize;
2657 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2658 unsigned long int *counts ;
2660 /* Possible optimization parameters: if we have NSYMS symbols we say
2661 that the hashing table must at least have NSYMS/4 and at most
2662 2*NSYMS buckets. */
2663 minsize = nsyms / 4;
2664 if (minsize == 0)
2665 minsize = 1;
2666 best_size = maxsize = nsyms * 2;
2668 /* Create array where we count the collisions in. We must use bfd_malloc
2669 since the size could be large. */
2670 counts = (unsigned long int *) bfd_malloc (maxsize
2671 * sizeof (unsigned long int));
2672 if (counts == NULL)
2674 free (hashcodes);
2675 return 0;
2678 /* Compute the "optimal" size for the hash table. The criteria is a
2679 minimal chain length. The minor criteria is (of course) the size
2680 of the table. */
2681 for (i = minsize; i < maxsize; ++i)
2683 /* Walk through the array of hashcodes and count the collisions. */
2684 BFD_HOST_U_64_BIT max;
2685 unsigned long int j;
2686 unsigned long int fact;
2688 memset (counts, '\0', i * sizeof (unsigned long int));
2690 /* Determine how often each hash bucket is used. */
2691 for (j = 0; j < nsyms; ++j)
2692 ++counts[hashcodes[j] % i];
2694 /* For the weight function we need some information about the
2695 pagesize on the target. This is information need not be 100%
2696 accurate. Since this information is not available (so far) we
2697 define it here to a reasonable default value. If it is crucial
2698 to have a better value some day simply define this value. */
2699 # ifndef BFD_TARGET_PAGESIZE
2700 # define BFD_TARGET_PAGESIZE (4096)
2701 # endif
2703 /* We in any case need 2 + NSYMS entries for the size values and
2704 the chains. */
2705 max = (2 + nsyms) * (ARCH_SIZE / 8);
2707 # if 1
2708 /* Variant 1: optimize for short chains. We add the squares
2709 of all the chain lengths (which favous many small chain
2710 over a few long chains). */
2711 for (j = 0; j < i; ++j)
2712 max += counts[j] * counts[j];
2714 /* This adds penalties for the overall size of the table. */
2715 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2716 max *= fact * fact;
2717 # else
2718 /* Variant 2: Optimize a lot more for small table. Here we
2719 also add squares of the size but we also add penalties for
2720 empty slots (the +1 term). */
2721 for (j = 0; j < i; ++j)
2722 max += (1 + counts[j]) * (1 + counts[j]);
2724 /* The overall size of the table is considered, but not as
2725 strong as in variant 1, where it is squared. */
2726 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2727 max *= fact;
2728 # endif
2730 /* Compare with current best results. */
2731 if (max < best_chlen)
2733 best_chlen = max;
2734 best_size = i;
2738 free (counts);
2740 else
2741 #endif /* defined (BFD_HOST_U_64_BIT) */
2743 /* This is the fallback solution if no 64bit type is available or if we
2744 are not supposed to spend much time on optimizations. We select the
2745 bucket count using a fixed set of numbers. */
2746 for (i = 0; elf_buckets[i] != 0; i++)
2748 best_size = elf_buckets[i];
2749 if (dynsymcount < elf_buckets[i + 1])
2750 break;
2754 /* Free the arrays we needed. */
2755 free (hashcodes);
2757 return best_size;
2760 /* Set up the sizes and contents of the ELF dynamic sections. This is
2761 called by the ELF linker emulation before_allocation routine. We
2762 must set the sizes of the sections before the linker sets the
2763 addresses of the various sections. */
2765 boolean
2766 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2767 export_dynamic, filter_shlib,
2768 auxiliary_filters, info, sinterpptr,
2769 verdefs)
2770 bfd *output_bfd;
2771 const char *soname;
2772 const char *rpath;
2773 boolean export_dynamic;
2774 const char *filter_shlib;
2775 const char * const *auxiliary_filters;
2776 struct bfd_link_info *info;
2777 asection **sinterpptr;
2778 struct bfd_elf_version_tree *verdefs;
2780 bfd_size_type soname_indx;
2781 bfd *dynobj;
2782 struct elf_backend_data *bed;
2783 struct elf_assign_sym_version_info asvinfo;
2785 *sinterpptr = NULL;
2787 soname_indx = (bfd_size_type) -1;
2789 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2790 return true;
2792 /* The backend may have to create some sections regardless of whether
2793 we're dynamic or not. */
2794 bed = get_elf_backend_data (output_bfd);
2795 if (bed->elf_backend_always_size_sections
2796 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2797 return false;
2799 dynobj = elf_hash_table (info)->dynobj;
2801 /* If there were no dynamic objects in the link, there is nothing to
2802 do here. */
2803 if (dynobj == NULL)
2804 return true;
2806 /* If we are supposed to export all symbols into the dynamic symbol
2807 table (this is not the normal case), then do so. */
2808 if (export_dynamic)
2810 struct elf_info_failed eif;
2812 eif.failed = false;
2813 eif.info = info;
2814 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2815 (PTR) &eif);
2816 if (eif.failed)
2817 return false;
2820 if (elf_hash_table (info)->dynamic_sections_created)
2822 struct elf_info_failed eif;
2823 struct elf_link_hash_entry *h;
2824 bfd_size_type strsize;
2826 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2827 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2829 if (soname != NULL)
2831 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2832 soname, true, true);
2833 if (soname_indx == (bfd_size_type) -1
2834 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2835 return false;
2838 if (info->symbolic)
2840 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2841 return false;
2844 if (rpath != NULL)
2846 bfd_size_type indx;
2848 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2849 true, true);
2850 if (indx == (bfd_size_type) -1
2851 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2852 return false;
2855 if (filter_shlib != NULL)
2857 bfd_size_type indx;
2859 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2860 filter_shlib, true, true);
2861 if (indx == (bfd_size_type) -1
2862 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2863 return false;
2866 if (auxiliary_filters != NULL)
2868 const char * const *p;
2870 for (p = auxiliary_filters; *p != NULL; p++)
2872 bfd_size_type indx;
2874 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2875 *p, true, true);
2876 if (indx == (bfd_size_type) -1
2877 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2878 return false;
2882 /* Attach all the symbols to their version information. */
2883 asvinfo.output_bfd = output_bfd;
2884 asvinfo.info = info;
2885 asvinfo.verdefs = verdefs;
2886 asvinfo.export_dynamic = export_dynamic;
2887 asvinfo.failed = false;
2889 elf_link_hash_traverse (elf_hash_table (info),
2890 elf_link_assign_sym_version,
2891 (PTR) &asvinfo);
2892 if (asvinfo.failed)
2893 return false;
2895 /* Find all symbols which were defined in a dynamic object and make
2896 the backend pick a reasonable value for them. */
2897 eif.failed = false;
2898 eif.info = info;
2899 elf_link_hash_traverse (elf_hash_table (info),
2900 elf_adjust_dynamic_symbol,
2901 (PTR) &eif);
2902 if (eif.failed)
2903 return false;
2905 /* Add some entries to the .dynamic section. We fill in some of the
2906 values later, in elf_bfd_final_link, but we must add the entries
2907 now so that we know the final size of the .dynamic section. */
2909 /* If there are initialization and/or finalization functions to
2910 call then add the corresponding DT_INIT/DT_FINI entries. */
2911 h = (info->init_function
2912 ? elf_link_hash_lookup (elf_hash_table (info),
2913 info->init_function, false,
2914 false, false)
2915 : NULL);
2916 if (h != NULL
2917 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2918 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2920 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2921 return false;
2923 h = (info->fini_function
2924 ? elf_link_hash_lookup (elf_hash_table (info),
2925 info->fini_function, false,
2926 false, false)
2927 : NULL);
2928 if (h != NULL
2929 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2930 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2932 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2933 return false;
2936 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2937 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2938 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2939 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2940 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2941 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2942 sizeof (Elf_External_Sym)))
2943 return false;
2946 /* The backend must work out the sizes of all the other dynamic
2947 sections. */
2948 if (bed->elf_backend_size_dynamic_sections
2949 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2950 return false;
2952 if (elf_hash_table (info)->dynamic_sections_created)
2954 size_t dynsymcount;
2955 asection *s;
2956 size_t bucketcount = 0;
2957 Elf_Internal_Sym isym;
2958 size_t hash_entry_size;
2960 /* Set up the version definition section. */
2961 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2962 BFD_ASSERT (s != NULL);
2964 /* We may have created additional version definitions if we are
2965 just linking a regular application. */
2966 verdefs = asvinfo.verdefs;
2968 if (verdefs == NULL)
2969 _bfd_strip_section_from_output (s);
2970 else
2972 unsigned int cdefs;
2973 bfd_size_type size;
2974 struct bfd_elf_version_tree *t;
2975 bfd_byte *p;
2976 Elf_Internal_Verdef def;
2977 Elf_Internal_Verdaux defaux;
2979 cdefs = 0;
2980 size = 0;
2982 /* Make space for the base version. */
2983 size += sizeof (Elf_External_Verdef);
2984 size += sizeof (Elf_External_Verdaux);
2985 ++cdefs;
2987 for (t = verdefs; t != NULL; t = t->next)
2989 struct bfd_elf_version_deps *n;
2991 size += sizeof (Elf_External_Verdef);
2992 size += sizeof (Elf_External_Verdaux);
2993 ++cdefs;
2995 for (n = t->deps; n != NULL; n = n->next)
2996 size += sizeof (Elf_External_Verdaux);
2999 s->_raw_size = size;
3000 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3001 if (s->contents == NULL && s->_raw_size != 0)
3002 return false;
3004 /* Fill in the version definition section. */
3006 p = s->contents;
3008 def.vd_version = VER_DEF_CURRENT;
3009 def.vd_flags = VER_FLG_BASE;
3010 def.vd_ndx = 1;
3011 def.vd_cnt = 1;
3012 def.vd_aux = sizeof (Elf_External_Verdef);
3013 def.vd_next = (sizeof (Elf_External_Verdef)
3014 + sizeof (Elf_External_Verdaux));
3016 if (soname_indx != (bfd_size_type) -1)
3018 def.vd_hash = bfd_elf_hash (soname);
3019 defaux.vda_name = soname_indx;
3021 else
3023 const char *name;
3024 bfd_size_type indx;
3026 name = output_bfd->filename;
3027 def.vd_hash = bfd_elf_hash (name);
3028 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3029 name, true, false);
3030 if (indx == (bfd_size_type) -1)
3031 return false;
3032 defaux.vda_name = indx;
3034 defaux.vda_next = 0;
3036 _bfd_elf_swap_verdef_out (output_bfd, &def,
3037 (Elf_External_Verdef *)p);
3038 p += sizeof (Elf_External_Verdef);
3039 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3040 (Elf_External_Verdaux *) p);
3041 p += sizeof (Elf_External_Verdaux);
3043 for (t = verdefs; t != NULL; t = t->next)
3045 unsigned int cdeps;
3046 struct bfd_elf_version_deps *n;
3047 struct elf_link_hash_entry *h;
3049 cdeps = 0;
3050 for (n = t->deps; n != NULL; n = n->next)
3051 ++cdeps;
3053 /* Add a symbol representing this version. */
3054 h = NULL;
3055 if (! (_bfd_generic_link_add_one_symbol
3056 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3057 (bfd_vma) 0, (const char *) NULL, false,
3058 get_elf_backend_data (dynobj)->collect,
3059 (struct bfd_link_hash_entry **) &h)))
3060 return false;
3061 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3062 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3063 h->type = STT_OBJECT;
3064 h->verinfo.vertree = t;
3066 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3067 return false;
3069 def.vd_version = VER_DEF_CURRENT;
3070 def.vd_flags = 0;
3071 if (t->globals == NULL && t->locals == NULL && ! t->used)
3072 def.vd_flags |= VER_FLG_WEAK;
3073 def.vd_ndx = t->vernum + 1;
3074 def.vd_cnt = cdeps + 1;
3075 def.vd_hash = bfd_elf_hash (t->name);
3076 def.vd_aux = sizeof (Elf_External_Verdef);
3077 if (t->next != NULL)
3078 def.vd_next = (sizeof (Elf_External_Verdef)
3079 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3080 else
3081 def.vd_next = 0;
3083 _bfd_elf_swap_verdef_out (output_bfd, &def,
3084 (Elf_External_Verdef *) p);
3085 p += sizeof (Elf_External_Verdef);
3087 defaux.vda_name = h->dynstr_index;
3088 if (t->deps == NULL)
3089 defaux.vda_next = 0;
3090 else
3091 defaux.vda_next = sizeof (Elf_External_Verdaux);
3092 t->name_indx = defaux.vda_name;
3094 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3095 (Elf_External_Verdaux *) p);
3096 p += sizeof (Elf_External_Verdaux);
3098 for (n = t->deps; n != NULL; n = n->next)
3100 if (n->version_needed == NULL)
3102 /* This can happen if there was an error in the
3103 version script. */
3104 defaux.vda_name = 0;
3106 else
3107 defaux.vda_name = n->version_needed->name_indx;
3108 if (n->next == NULL)
3109 defaux.vda_next = 0;
3110 else
3111 defaux.vda_next = sizeof (Elf_External_Verdaux);
3113 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3114 (Elf_External_Verdaux *) p);
3115 p += sizeof (Elf_External_Verdaux);
3119 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3120 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3121 return false;
3123 elf_tdata (output_bfd)->cverdefs = cdefs;
3126 /* Work out the size of the version reference section. */
3128 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3129 BFD_ASSERT (s != NULL);
3131 struct elf_find_verdep_info sinfo;
3133 sinfo.output_bfd = output_bfd;
3134 sinfo.info = info;
3135 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3136 if (sinfo.vers == 0)
3137 sinfo.vers = 1;
3138 sinfo.failed = false;
3140 elf_link_hash_traverse (elf_hash_table (info),
3141 elf_link_find_version_dependencies,
3142 (PTR) &sinfo);
3144 if (elf_tdata (output_bfd)->verref == NULL)
3145 _bfd_strip_section_from_output (s);
3146 else
3148 Elf_Internal_Verneed *t;
3149 unsigned int size;
3150 unsigned int crefs;
3151 bfd_byte *p;
3153 /* Build the version definition section. */
3154 size = 0;
3155 crefs = 0;
3156 for (t = elf_tdata (output_bfd)->verref;
3157 t != NULL;
3158 t = t->vn_nextref)
3160 Elf_Internal_Vernaux *a;
3162 size += sizeof (Elf_External_Verneed);
3163 ++crefs;
3164 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3165 size += sizeof (Elf_External_Vernaux);
3168 s->_raw_size = size;
3169 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3170 if (s->contents == NULL)
3171 return false;
3173 p = s->contents;
3174 for (t = elf_tdata (output_bfd)->verref;
3175 t != NULL;
3176 t = t->vn_nextref)
3178 unsigned int caux;
3179 Elf_Internal_Vernaux *a;
3180 bfd_size_type indx;
3182 caux = 0;
3183 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3184 ++caux;
3186 t->vn_version = VER_NEED_CURRENT;
3187 t->vn_cnt = caux;
3188 if (elf_dt_name (t->vn_bfd) != NULL)
3189 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3190 elf_dt_name (t->vn_bfd),
3191 true, false);
3192 else
3193 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3194 t->vn_bfd->filename, true, false);
3195 if (indx == (bfd_size_type) -1)
3196 return false;
3197 t->vn_file = indx;
3198 t->vn_aux = sizeof (Elf_External_Verneed);
3199 if (t->vn_nextref == NULL)
3200 t->vn_next = 0;
3201 else
3202 t->vn_next = (sizeof (Elf_External_Verneed)
3203 + caux * sizeof (Elf_External_Vernaux));
3205 _bfd_elf_swap_verneed_out (output_bfd, t,
3206 (Elf_External_Verneed *) p);
3207 p += sizeof (Elf_External_Verneed);
3209 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3211 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3212 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3213 a->vna_nodename, true, false);
3214 if (indx == (bfd_size_type) -1)
3215 return false;
3216 a->vna_name = indx;
3217 if (a->vna_nextptr == NULL)
3218 a->vna_next = 0;
3219 else
3220 a->vna_next = sizeof (Elf_External_Vernaux);
3222 _bfd_elf_swap_vernaux_out (output_bfd, a,
3223 (Elf_External_Vernaux *) p);
3224 p += sizeof (Elf_External_Vernaux);
3228 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3229 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3230 return false;
3232 elf_tdata (output_bfd)->cverrefs = crefs;
3236 /* Assign dynsym indicies. In a shared library we generate a
3237 section symbol for each output section, which come first.
3238 Next come all of the back-end allocated local dynamic syms,
3239 followed by the rest of the global symbols. */
3241 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3243 /* Work out the size of the symbol version section. */
3244 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3245 BFD_ASSERT (s != NULL);
3246 if (dynsymcount == 0
3247 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3249 _bfd_strip_section_from_output (s);
3250 /* The DYNSYMCOUNT might have changed if we were going to
3251 output a dynamic symbol table entry for S. */
3252 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3254 else
3256 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3257 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3258 if (s->contents == NULL)
3259 return false;
3261 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3262 return false;
3265 /* Set the size of the .dynsym and .hash sections. We counted
3266 the number of dynamic symbols in elf_link_add_object_symbols.
3267 We will build the contents of .dynsym and .hash when we build
3268 the final symbol table, because until then we do not know the
3269 correct value to give the symbols. We built the .dynstr
3270 section as we went along in elf_link_add_object_symbols. */
3271 s = bfd_get_section_by_name (dynobj, ".dynsym");
3272 BFD_ASSERT (s != NULL);
3273 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3274 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3275 if (s->contents == NULL && s->_raw_size != 0)
3276 return false;
3278 /* The first entry in .dynsym is a dummy symbol. */
3279 isym.st_value = 0;
3280 isym.st_size = 0;
3281 isym.st_name = 0;
3282 isym.st_info = 0;
3283 isym.st_other = 0;
3284 isym.st_shndx = 0;
3285 elf_swap_symbol_out (output_bfd, &isym,
3286 (PTR) (Elf_External_Sym *) s->contents);
3288 /* Compute the size of the hashing table. As a side effect this
3289 computes the hash values for all the names we export. */
3290 bucketcount = compute_bucket_count (info);
3292 s = bfd_get_section_by_name (dynobj, ".hash");
3293 BFD_ASSERT (s != NULL);
3294 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3295 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3296 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3297 if (s->contents == NULL)
3298 return false;
3299 memset (s->contents, 0, (size_t) s->_raw_size);
3301 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3302 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3303 s->contents + hash_entry_size);
3305 elf_hash_table (info)->bucketcount = bucketcount;
3307 s = bfd_get_section_by_name (dynobj, ".dynstr");
3308 BFD_ASSERT (s != NULL);
3309 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3311 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3312 return false;
3315 return true;
3318 /* Fix up the flags for a symbol. This handles various cases which
3319 can only be fixed after all the input files are seen. This is
3320 currently called by both adjust_dynamic_symbol and
3321 assign_sym_version, which is unnecessary but perhaps more robust in
3322 the face of future changes. */
3324 static boolean
3325 elf_fix_symbol_flags (h, eif)
3326 struct elf_link_hash_entry *h;
3327 struct elf_info_failed *eif;
3329 /* If this symbol was mentioned in a non-ELF file, try to set
3330 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3331 permit a non-ELF file to correctly refer to a symbol defined in
3332 an ELF dynamic object. */
3333 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3335 if (h->root.type != bfd_link_hash_defined
3336 && h->root.type != bfd_link_hash_defweak)
3337 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3338 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3339 else
3341 if (h->root.u.def.section->owner != NULL
3342 && (bfd_get_flavour (h->root.u.def.section->owner)
3343 == bfd_target_elf_flavour))
3344 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3345 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3346 else
3347 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3350 if (h->dynindx == -1
3351 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3352 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3354 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3356 eif->failed = true;
3357 return false;
3361 else
3363 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3364 was first seen in a non-ELF file. Fortunately, if the symbol
3365 was first seen in an ELF file, we're probably OK unless the
3366 symbol was defined in a non-ELF file. Catch that case here.
3367 FIXME: We're still in trouble if the symbol was first seen in
3368 a dynamic object, and then later in a non-ELF regular object. */
3369 if ((h->root.type == bfd_link_hash_defined
3370 || h->root.type == bfd_link_hash_defweak)
3371 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3372 && (h->root.u.def.section->owner != NULL
3373 ? (bfd_get_flavour (h->root.u.def.section->owner)
3374 != bfd_target_elf_flavour)
3375 : (bfd_is_abs_section (h->root.u.def.section)
3376 && (h->elf_link_hash_flags
3377 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3378 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3381 /* If this is a final link, and the symbol was defined as a common
3382 symbol in a regular object file, and there was no definition in
3383 any dynamic object, then the linker will have allocated space for
3384 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3385 flag will not have been set. */
3386 if (h->root.type == bfd_link_hash_defined
3387 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3388 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3389 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3390 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3391 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3393 /* If -Bsymbolic was used (which means to bind references to global
3394 symbols to the definition within the shared object), and this
3395 symbol was defined in a regular object, then it actually doesn't
3396 need a PLT entry. */
3397 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3398 && eif->info->shared
3399 && eif->info->symbolic
3400 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3402 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3403 h->plt.offset = (bfd_vma) -1;
3406 /* If this is a weak defined symbol in a dynamic object, and we know
3407 the real definition in the dynamic object, copy interesting flags
3408 over to the real definition. */
3409 if (h->weakdef != NULL)
3411 struct elf_link_hash_entry *weakdef;
3413 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3414 || h->root.type == bfd_link_hash_defweak);
3415 weakdef = h->weakdef;
3416 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3417 || weakdef->root.type == bfd_link_hash_defweak);
3418 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3420 /* If the real definition is defined by a regular object file,
3421 don't do anything special. See the longer description in
3422 elf_adjust_dynamic_symbol, below. */
3423 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3424 h->weakdef = NULL;
3425 else
3426 weakdef->elf_link_hash_flags |=
3427 (h->elf_link_hash_flags
3428 & (ELF_LINK_HASH_REF_REGULAR
3429 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3430 | ELF_LINK_NON_GOT_REF));
3433 return true;
3436 /* Make the backend pick a good value for a dynamic symbol. This is
3437 called via elf_link_hash_traverse, and also calls itself
3438 recursively. */
3440 static boolean
3441 elf_adjust_dynamic_symbol (h, data)
3442 struct elf_link_hash_entry *h;
3443 PTR data;
3445 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3446 bfd *dynobj;
3447 struct elf_backend_data *bed;
3449 /* Ignore indirect symbols. These are added by the versioning code. */
3450 if (h->root.type == bfd_link_hash_indirect)
3451 return true;
3453 /* Fix the symbol flags. */
3454 if (! elf_fix_symbol_flags (h, eif))
3455 return false;
3457 /* If this symbol does not require a PLT entry, and it is not
3458 defined by a dynamic object, or is not referenced by a regular
3459 object, ignore it. We do have to handle a weak defined symbol,
3460 even if no regular object refers to it, if we decided to add it
3461 to the dynamic symbol table. FIXME: Do we normally need to worry
3462 about symbols which are defined by one dynamic object and
3463 referenced by another one? */
3464 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3465 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3466 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3467 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3468 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3470 h->plt.offset = (bfd_vma) -1;
3471 return true;
3474 /* If we've already adjusted this symbol, don't do it again. This
3475 can happen via a recursive call. */
3476 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3477 return true;
3479 /* Don't look at this symbol again. Note that we must set this
3480 after checking the above conditions, because we may look at a
3481 symbol once, decide not to do anything, and then get called
3482 recursively later after REF_REGULAR is set below. */
3483 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3485 /* If this is a weak definition, and we know a real definition, and
3486 the real symbol is not itself defined by a regular object file,
3487 then get a good value for the real definition. We handle the
3488 real symbol first, for the convenience of the backend routine.
3490 Note that there is a confusing case here. If the real definition
3491 is defined by a regular object file, we don't get the real symbol
3492 from the dynamic object, but we do get the weak symbol. If the
3493 processor backend uses a COPY reloc, then if some routine in the
3494 dynamic object changes the real symbol, we will not see that
3495 change in the corresponding weak symbol. This is the way other
3496 ELF linkers work as well, and seems to be a result of the shared
3497 library model.
3499 I will clarify this issue. Most SVR4 shared libraries define the
3500 variable _timezone and define timezone as a weak synonym. The
3501 tzset call changes _timezone. If you write
3502 extern int timezone;
3503 int _timezone = 5;
3504 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3505 you might expect that, since timezone is a synonym for _timezone,
3506 the same number will print both times. However, if the processor
3507 backend uses a COPY reloc, then actually timezone will be copied
3508 into your process image, and, since you define _timezone
3509 yourself, _timezone will not. Thus timezone and _timezone will
3510 wind up at different memory locations. The tzset call will set
3511 _timezone, leaving timezone unchanged. */
3513 if (h->weakdef != NULL)
3515 /* If we get to this point, we know there is an implicit
3516 reference by a regular object file via the weak symbol H.
3517 FIXME: Is this really true? What if the traversal finds
3518 H->WEAKDEF before it finds H? */
3519 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3521 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3522 return false;
3525 /* If a symbol has no type and no size and does not require a PLT
3526 entry, then we are probably about to do the wrong thing here: we
3527 are probably going to create a COPY reloc for an empty object.
3528 This case can arise when a shared object is built with assembly
3529 code, and the assembly code fails to set the symbol type. */
3530 if (h->size == 0
3531 && h->type == STT_NOTYPE
3532 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3533 (*_bfd_error_handler)
3534 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3535 h->root.root.string);
3537 dynobj = elf_hash_table (eif->info)->dynobj;
3538 bed = get_elf_backend_data (dynobj);
3539 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3541 eif->failed = true;
3542 return false;
3545 return true;
3548 /* This routine is used to export all defined symbols into the dynamic
3549 symbol table. It is called via elf_link_hash_traverse. */
3551 static boolean
3552 elf_export_symbol (h, data)
3553 struct elf_link_hash_entry *h;
3554 PTR data;
3556 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3558 /* Ignore indirect symbols. These are added by the versioning code. */
3559 if (h->root.type == bfd_link_hash_indirect)
3560 return true;
3562 if (h->dynindx == -1
3563 && (h->elf_link_hash_flags
3564 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3566 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3568 eif->failed = true;
3569 return false;
3573 return true;
3576 /* Look through the symbols which are defined in other shared
3577 libraries and referenced here. Update the list of version
3578 dependencies. This will be put into the .gnu.version_r section.
3579 This function is called via elf_link_hash_traverse. */
3581 static boolean
3582 elf_link_find_version_dependencies (h, data)
3583 struct elf_link_hash_entry *h;
3584 PTR data;
3586 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3587 Elf_Internal_Verneed *t;
3588 Elf_Internal_Vernaux *a;
3590 /* We only care about symbols defined in shared objects with version
3591 information. */
3592 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3593 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3594 || h->dynindx == -1
3595 || h->verinfo.verdef == NULL)
3596 return true;
3598 /* See if we already know about this version. */
3599 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3601 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3602 continue;
3604 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3605 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3606 return true;
3608 break;
3611 /* This is a new version. Add it to tree we are building. */
3613 if (t == NULL)
3615 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3616 if (t == NULL)
3618 rinfo->failed = true;
3619 return false;
3622 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3623 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3624 elf_tdata (rinfo->output_bfd)->verref = t;
3627 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3629 /* Note that we are copying a string pointer here, and testing it
3630 above. If bfd_elf_string_from_elf_section is ever changed to
3631 discard the string data when low in memory, this will have to be
3632 fixed. */
3633 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3635 a->vna_flags = h->verinfo.verdef->vd_flags;
3636 a->vna_nextptr = t->vn_auxptr;
3638 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3639 ++rinfo->vers;
3641 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3643 t->vn_auxptr = a;
3645 return true;
3648 /* Figure out appropriate versions for all the symbols. We may not
3649 have the version number script until we have read all of the input
3650 files, so until that point we don't know which symbols should be
3651 local. This function is called via elf_link_hash_traverse. */
3653 static boolean
3654 elf_link_assign_sym_version (h, data)
3655 struct elf_link_hash_entry *h;
3656 PTR data;
3658 struct elf_assign_sym_version_info *sinfo =
3659 (struct elf_assign_sym_version_info *) data;
3660 struct bfd_link_info *info = sinfo->info;
3661 struct elf_info_failed eif;
3662 char *p;
3664 /* Fix the symbol flags. */
3665 eif.failed = false;
3666 eif.info = info;
3667 if (! elf_fix_symbol_flags (h, &eif))
3669 if (eif.failed)
3670 sinfo->failed = true;
3671 return false;
3674 /* We only need version numbers for symbols defined in regular
3675 objects. */
3676 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3677 return true;
3679 p = strchr (h->root.root.string, ELF_VER_CHR);
3680 if (p != NULL && h->verinfo.vertree == NULL)
3682 struct bfd_elf_version_tree *t;
3683 boolean hidden;
3685 hidden = true;
3687 /* There are two consecutive ELF_VER_CHR characters if this is
3688 not a hidden symbol. */
3689 ++p;
3690 if (*p == ELF_VER_CHR)
3692 hidden = false;
3693 ++p;
3696 /* If there is no version string, we can just return out. */
3697 if (*p == '\0')
3699 if (hidden)
3700 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3701 return true;
3704 /* Look for the version. If we find it, it is no longer weak. */
3705 for (t = sinfo->verdefs; t != NULL; t = t->next)
3707 if (strcmp (t->name, p) == 0)
3709 int len;
3710 char *alc;
3711 struct bfd_elf_version_expr *d;
3713 len = p - h->root.root.string;
3714 alc = bfd_alloc (sinfo->output_bfd, len);
3715 if (alc == NULL)
3716 return false;
3717 strncpy (alc, h->root.root.string, len - 1);
3718 alc[len - 1] = '\0';
3719 if (alc[len - 2] == ELF_VER_CHR)
3720 alc[len - 2] = '\0';
3722 h->verinfo.vertree = t;
3723 t->used = true;
3724 d = NULL;
3726 if (t->globals != NULL)
3728 for (d = t->globals; d != NULL; d = d->next)
3729 if ((*d->match) (d, alc))
3730 break;
3733 /* See if there is anything to force this symbol to
3734 local scope. */
3735 if (d == NULL && t->locals != NULL)
3737 for (d = t->locals; d != NULL; d = d->next)
3739 if ((*d->match) (d, alc))
3741 if (h->dynindx != -1
3742 && info->shared
3743 && ! sinfo->export_dynamic)
3745 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3746 h->elf_link_hash_flags &=~
3747 ELF_LINK_HASH_NEEDS_PLT;
3748 h->dynindx = -1;
3749 h->plt.offset = (bfd_vma) -1;
3750 /* FIXME: The name of the symbol has
3751 already been recorded in the dynamic
3752 string table section. */
3755 break;
3760 bfd_release (sinfo->output_bfd, alc);
3761 break;
3765 /* If we are building an application, we need to create a
3766 version node for this version. */
3767 if (t == NULL && ! info->shared)
3769 struct bfd_elf_version_tree **pp;
3770 int version_index;
3772 /* If we aren't going to export this symbol, we don't need
3773 to worry about it. */
3774 if (h->dynindx == -1)
3775 return true;
3777 t = ((struct bfd_elf_version_tree *)
3778 bfd_alloc (sinfo->output_bfd, sizeof *t));
3779 if (t == NULL)
3781 sinfo->failed = true;
3782 return false;
3785 t->next = NULL;
3786 t->name = p;
3787 t->globals = NULL;
3788 t->locals = NULL;
3789 t->deps = NULL;
3790 t->name_indx = (unsigned int) -1;
3791 t->used = true;
3793 version_index = 1;
3794 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3795 ++version_index;
3796 t->vernum = version_index;
3798 *pp = t;
3800 h->verinfo.vertree = t;
3802 else if (t == NULL)
3804 /* We could not find the version for a symbol when
3805 generating a shared archive. Return an error. */
3806 (*_bfd_error_handler)
3807 (_("%s: undefined versioned symbol name %s"),
3808 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3809 bfd_set_error (bfd_error_bad_value);
3810 sinfo->failed = true;
3811 return false;
3814 if (hidden)
3815 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3818 /* If we don't have a version for this symbol, see if we can find
3819 something. */
3820 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3822 struct bfd_elf_version_tree *t;
3823 struct bfd_elf_version_tree *deflt;
3824 struct bfd_elf_version_expr *d;
3826 /* See if can find what version this symbol is in. If the
3827 symbol is supposed to be local, then don't actually register
3828 it. */
3829 deflt = NULL;
3830 for (t = sinfo->verdefs; t != NULL; t = t->next)
3832 if (t->globals != NULL)
3834 for (d = t->globals; d != NULL; d = d->next)
3836 if ((*d->match) (d, h->root.root.string))
3838 h->verinfo.vertree = t;
3839 break;
3843 if (d != NULL)
3844 break;
3847 if (t->locals != NULL)
3849 for (d = t->locals; d != NULL; d = d->next)
3851 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3852 deflt = t;
3853 else if ((*d->match) (d, h->root.root.string))
3855 h->verinfo.vertree = t;
3856 if (h->dynindx != -1
3857 && info->shared
3858 && ! sinfo->export_dynamic)
3860 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3861 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3862 h->dynindx = -1;
3863 h->plt.offset = (bfd_vma) -1;
3864 /* FIXME: The name of the symbol has already
3865 been recorded in the dynamic string table
3866 section. */
3868 break;
3872 if (d != NULL)
3873 break;
3877 if (deflt != NULL && h->verinfo.vertree == NULL)
3879 h->verinfo.vertree = deflt;
3880 if (h->dynindx != -1
3881 && info->shared
3882 && ! sinfo->export_dynamic)
3884 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3885 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3886 h->dynindx = -1;
3887 h->plt.offset = (bfd_vma) -1;
3888 /* FIXME: The name of the symbol has already been
3889 recorded in the dynamic string table section. */
3894 return true;
3897 /* Final phase of ELF linker. */
3899 /* A structure we use to avoid passing large numbers of arguments. */
3901 struct elf_final_link_info
3903 /* General link information. */
3904 struct bfd_link_info *info;
3905 /* Output BFD. */
3906 bfd *output_bfd;
3907 /* Symbol string table. */
3908 struct bfd_strtab_hash *symstrtab;
3909 /* .dynsym section. */
3910 asection *dynsym_sec;
3911 /* .hash section. */
3912 asection *hash_sec;
3913 /* symbol version section (.gnu.version). */
3914 asection *symver_sec;
3915 /* Buffer large enough to hold contents of any section. */
3916 bfd_byte *contents;
3917 /* Buffer large enough to hold external relocs of any section. */
3918 PTR external_relocs;
3919 /* Buffer large enough to hold internal relocs of any section. */
3920 Elf_Internal_Rela *internal_relocs;
3921 /* Buffer large enough to hold external local symbols of any input
3922 BFD. */
3923 Elf_External_Sym *external_syms;
3924 /* Buffer large enough to hold internal local symbols of any input
3925 BFD. */
3926 Elf_Internal_Sym *internal_syms;
3927 /* Array large enough to hold a symbol index for each local symbol
3928 of any input BFD. */
3929 long *indices;
3930 /* Array large enough to hold a section pointer for each local
3931 symbol of any input BFD. */
3932 asection **sections;
3933 /* Buffer to hold swapped out symbols. */
3934 Elf_External_Sym *symbuf;
3935 /* Number of swapped out symbols in buffer. */
3936 size_t symbuf_count;
3937 /* Number of symbols which fit in symbuf. */
3938 size_t symbuf_size;
3941 static boolean elf_link_output_sym
3942 PARAMS ((struct elf_final_link_info *, const char *,
3943 Elf_Internal_Sym *, asection *));
3944 static boolean elf_link_flush_output_syms
3945 PARAMS ((struct elf_final_link_info *));
3946 static boolean elf_link_output_extsym
3947 PARAMS ((struct elf_link_hash_entry *, PTR));
3948 static boolean elf_link_input_bfd
3949 PARAMS ((struct elf_final_link_info *, bfd *));
3950 static boolean elf_reloc_link_order
3951 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3952 struct bfd_link_order *));
3954 /* This struct is used to pass information to elf_link_output_extsym. */
3956 struct elf_outext_info
3958 boolean failed;
3959 boolean localsyms;
3960 struct elf_final_link_info *finfo;
3963 /* Compute the size of, and allocate space for, REL_HDR which is the
3964 section header for a section containing relocations for O. */
3966 static boolean
3967 elf_link_size_reloc_section (abfd, rel_hdr, o)
3968 bfd *abfd;
3969 Elf_Internal_Shdr *rel_hdr;
3970 asection *o;
3972 register struct elf_link_hash_entry **p, **pend;
3973 unsigned reloc_count;
3975 /* Figure out how many relocations there will be. */
3976 if (rel_hdr == &elf_section_data (o)->rel_hdr)
3977 reloc_count = elf_section_data (o)->rel_count;
3978 else
3979 reloc_count = elf_section_data (o)->rel_count2;
3981 /* That allows us to calculate the size of the section. */
3982 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
3984 /* The contents field must last into write_object_contents, so we
3985 allocate it with bfd_alloc rather than malloc. */
3986 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3987 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3988 return false;
3990 /* We only allocate one set of hash entries, so we only do it the
3991 first time we are called. */
3992 if (elf_section_data (o)->rel_hashes == NULL)
3994 p = ((struct elf_link_hash_entry **)
3995 bfd_malloc (o->reloc_count
3996 * sizeof (struct elf_link_hash_entry *)));
3997 if (p == NULL && o->reloc_count != 0)
3998 return false;
4000 elf_section_data (o)->rel_hashes = p;
4001 pend = p + o->reloc_count;
4002 for (; p < pend; p++)
4003 *p = NULL;
4006 return true;
4009 /* When performing a relocateable link, the input relocations are
4010 preserved. But, if they reference global symbols, the indices
4011 referenced must be updated. Update all the relocations in
4012 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4014 static void
4015 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4016 bfd *abfd;
4017 Elf_Internal_Shdr *rel_hdr;
4018 unsigned int count;
4019 struct elf_link_hash_entry **rel_hash;
4021 unsigned int i;
4023 for (i = 0; i < count; i++, rel_hash++)
4025 if (*rel_hash == NULL)
4026 continue;
4028 BFD_ASSERT ((*rel_hash)->indx >= 0);
4030 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4032 Elf_External_Rel *erel;
4033 Elf_Internal_Rel irel;
4035 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4036 elf_swap_reloc_in (abfd, erel, &irel);
4037 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
4038 ELF_R_TYPE (irel.r_info));
4039 elf_swap_reloc_out (abfd, &irel, erel);
4041 else
4043 Elf_External_Rela *erela;
4044 Elf_Internal_Rela irela;
4046 BFD_ASSERT (rel_hdr->sh_entsize
4047 == sizeof (Elf_External_Rela));
4049 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4050 elf_swap_reloca_in (abfd, erela, &irela);
4051 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4052 ELF_R_TYPE (irela.r_info));
4053 elf_swap_reloca_out (abfd, &irela, erela);
4058 /* Do the final step of an ELF link. */
4060 boolean
4061 elf_bfd_final_link (abfd, info)
4062 bfd *abfd;
4063 struct bfd_link_info *info;
4065 boolean dynamic;
4066 bfd *dynobj;
4067 struct elf_final_link_info finfo;
4068 register asection *o;
4069 register struct bfd_link_order *p;
4070 register bfd *sub;
4071 size_t max_contents_size;
4072 size_t max_external_reloc_size;
4073 size_t max_internal_reloc_count;
4074 size_t max_sym_count;
4075 file_ptr off;
4076 Elf_Internal_Sym elfsym;
4077 unsigned int i;
4078 Elf_Internal_Shdr *symtab_hdr;
4079 Elf_Internal_Shdr *symstrtab_hdr;
4080 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4081 struct elf_outext_info eoinfo;
4083 if (info->shared)
4084 abfd->flags |= DYNAMIC;
4086 dynamic = elf_hash_table (info)->dynamic_sections_created;
4087 dynobj = elf_hash_table (info)->dynobj;
4089 finfo.info = info;
4090 finfo.output_bfd = abfd;
4091 finfo.symstrtab = elf_stringtab_init ();
4092 if (finfo.symstrtab == NULL)
4093 return false;
4095 if (! dynamic)
4097 finfo.dynsym_sec = NULL;
4098 finfo.hash_sec = NULL;
4099 finfo.symver_sec = NULL;
4101 else
4103 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4104 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4105 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4106 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4107 /* Note that it is OK if symver_sec is NULL. */
4110 finfo.contents = NULL;
4111 finfo.external_relocs = NULL;
4112 finfo.internal_relocs = NULL;
4113 finfo.external_syms = NULL;
4114 finfo.internal_syms = NULL;
4115 finfo.indices = NULL;
4116 finfo.sections = NULL;
4117 finfo.symbuf = NULL;
4118 finfo.symbuf_count = 0;
4120 /* Count up the number of relocations we will output for each output
4121 section, so that we know the sizes of the reloc sections. We
4122 also figure out some maximum sizes. */
4123 max_contents_size = 0;
4124 max_external_reloc_size = 0;
4125 max_internal_reloc_count = 0;
4126 max_sym_count = 0;
4127 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4129 o->reloc_count = 0;
4131 for (p = o->link_order_head; p != NULL; p = p->next)
4133 if (p->type == bfd_section_reloc_link_order
4134 || p->type == bfd_symbol_reloc_link_order)
4135 ++o->reloc_count;
4136 else if (p->type == bfd_indirect_link_order)
4138 asection *sec;
4140 sec = p->u.indirect.section;
4142 /* Mark all sections which are to be included in the
4143 link. This will normally be every section. We need
4144 to do this so that we can identify any sections which
4145 the linker has decided to not include. */
4146 sec->linker_mark = true;
4148 if (info->relocateable)
4149 o->reloc_count += sec->reloc_count;
4151 if (sec->_raw_size > max_contents_size)
4152 max_contents_size = sec->_raw_size;
4153 if (sec->_cooked_size > max_contents_size)
4154 max_contents_size = sec->_cooked_size;
4156 /* We are interested in just local symbols, not all
4157 symbols. */
4158 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4159 && (sec->owner->flags & DYNAMIC) == 0)
4161 size_t sym_count;
4163 if (elf_bad_symtab (sec->owner))
4164 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4165 / sizeof (Elf_External_Sym));
4166 else
4167 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4169 if (sym_count > max_sym_count)
4170 max_sym_count = sym_count;
4172 if ((sec->flags & SEC_RELOC) != 0)
4174 size_t ext_size;
4176 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4177 if (ext_size > max_external_reloc_size)
4178 max_external_reloc_size = ext_size;
4179 if (sec->reloc_count > max_internal_reloc_count)
4180 max_internal_reloc_count = sec->reloc_count;
4186 if (o->reloc_count > 0)
4187 o->flags |= SEC_RELOC;
4188 else
4190 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4191 set it (this is probably a bug) and if it is set
4192 assign_section_numbers will create a reloc section. */
4193 o->flags &=~ SEC_RELOC;
4196 /* If the SEC_ALLOC flag is not set, force the section VMA to
4197 zero. This is done in elf_fake_sections as well, but forcing
4198 the VMA to 0 here will ensure that relocs against these
4199 sections are handled correctly. */
4200 if ((o->flags & SEC_ALLOC) == 0
4201 && ! o->user_set_vma)
4202 o->vma = 0;
4205 /* Figure out the file positions for everything but the symbol table
4206 and the relocs. We set symcount to force assign_section_numbers
4207 to create a symbol table. */
4208 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4209 BFD_ASSERT (! abfd->output_has_begun);
4210 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4211 goto error_return;
4213 /* Figure out how many relocations we will have in each section.
4214 Just using RELOC_COUNT isn't good enough since that doesn't
4215 maintain a separate value for REL vs. RELA relocations. */
4216 if (info->relocateable)
4217 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4218 for (o = sub->sections; o != NULL; o = o->next)
4220 asection *output_section;
4222 if (! o->linker_mark)
4224 /* This section was omitted from the link. */
4225 continue;
4228 output_section = o->output_section;
4230 if (output_section != NULL
4231 && (o->flags & SEC_RELOC) != 0)
4233 struct bfd_elf_section_data *esdi
4234 = elf_section_data (o);
4235 struct bfd_elf_section_data *esdo
4236 = elf_section_data (output_section);
4237 unsigned int *rel_count;
4238 unsigned int *rel_count2;
4240 /* We must be careful to add the relocation froms the
4241 input section to the right output count. */
4242 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4244 rel_count = &esdo->rel_count;
4245 rel_count2 = &esdo->rel_count2;
4247 else
4249 rel_count = &esdo->rel_count2;
4250 rel_count2 = &esdo->rel_count;
4253 *rel_count += (esdi->rel_hdr.sh_size
4254 / esdi->rel_hdr.sh_entsize);
4255 if (esdi->rel_hdr2)
4256 *rel_count2 += (esdi->rel_hdr2->sh_size
4257 / esdi->rel_hdr2->sh_entsize);
4261 /* That created the reloc sections. Set their sizes, and assign
4262 them file positions, and allocate some buffers. */
4263 for (o = abfd->sections; o != NULL; o = o->next)
4265 if ((o->flags & SEC_RELOC) != 0)
4267 if (!elf_link_size_reloc_section (abfd,
4268 &elf_section_data (o)->rel_hdr,
4270 goto error_return;
4272 if (elf_section_data (o)->rel_hdr2
4273 && !elf_link_size_reloc_section (abfd,
4274 elf_section_data (o)->rel_hdr2,
4276 goto error_return;
4279 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4280 to count upwards while actually outputting the relocations. */
4281 elf_section_data (o)->rel_count = 0;
4282 elf_section_data (o)->rel_count2 = 0;
4285 _bfd_elf_assign_file_positions_for_relocs (abfd);
4287 /* We have now assigned file positions for all the sections except
4288 .symtab and .strtab. We start the .symtab section at the current
4289 file position, and write directly to it. We build the .strtab
4290 section in memory. */
4291 bfd_get_symcount (abfd) = 0;
4292 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4293 /* sh_name is set in prep_headers. */
4294 symtab_hdr->sh_type = SHT_SYMTAB;
4295 symtab_hdr->sh_flags = 0;
4296 symtab_hdr->sh_addr = 0;
4297 symtab_hdr->sh_size = 0;
4298 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4299 /* sh_link is set in assign_section_numbers. */
4300 /* sh_info is set below. */
4301 /* sh_offset is set just below. */
4302 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4304 off = elf_tdata (abfd)->next_file_pos;
4305 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4307 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4308 incorrect. We do not yet know the size of the .symtab section.
4309 We correct next_file_pos below, after we do know the size. */
4311 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4312 continuously seeking to the right position in the file. */
4313 if (! info->keep_memory || max_sym_count < 20)
4314 finfo.symbuf_size = 20;
4315 else
4316 finfo.symbuf_size = max_sym_count;
4317 finfo.symbuf = ((Elf_External_Sym *)
4318 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4319 if (finfo.symbuf == NULL)
4320 goto error_return;
4322 /* Start writing out the symbol table. The first symbol is always a
4323 dummy symbol. */
4324 if (info->strip != strip_all || info->relocateable)
4326 elfsym.st_value = 0;
4327 elfsym.st_size = 0;
4328 elfsym.st_info = 0;
4329 elfsym.st_other = 0;
4330 elfsym.st_shndx = SHN_UNDEF;
4331 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4332 &elfsym, bfd_und_section_ptr))
4333 goto error_return;
4336 #if 0
4337 /* Some standard ELF linkers do this, but we don't because it causes
4338 bootstrap comparison failures. */
4339 /* Output a file symbol for the output file as the second symbol.
4340 We output this even if we are discarding local symbols, although
4341 I'm not sure if this is correct. */
4342 elfsym.st_value = 0;
4343 elfsym.st_size = 0;
4344 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4345 elfsym.st_other = 0;
4346 elfsym.st_shndx = SHN_ABS;
4347 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4348 &elfsym, bfd_abs_section_ptr))
4349 goto error_return;
4350 #endif
4352 /* Output a symbol for each section. We output these even if we are
4353 discarding local symbols, since they are used for relocs. These
4354 symbols have no names. We store the index of each one in the
4355 index field of the section, so that we can find it again when
4356 outputting relocs. */
4357 if (info->strip != strip_all || info->relocateable)
4359 elfsym.st_size = 0;
4360 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4361 elfsym.st_other = 0;
4362 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4364 o = section_from_elf_index (abfd, i);
4365 if (o != NULL)
4366 o->target_index = bfd_get_symcount (abfd);
4367 elfsym.st_shndx = i;
4368 if (info->relocateable || o == NULL)
4369 elfsym.st_value = 0;
4370 else
4371 elfsym.st_value = o->vma;
4372 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4373 &elfsym, o))
4374 goto error_return;
4378 /* Allocate some memory to hold information read in from the input
4379 files. */
4380 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4381 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4382 finfo.internal_relocs = ((Elf_Internal_Rela *)
4383 bfd_malloc (max_internal_reloc_count
4384 * sizeof (Elf_Internal_Rela)
4385 * bed->s->int_rels_per_ext_rel));
4386 finfo.external_syms = ((Elf_External_Sym *)
4387 bfd_malloc (max_sym_count
4388 * sizeof (Elf_External_Sym)));
4389 finfo.internal_syms = ((Elf_Internal_Sym *)
4390 bfd_malloc (max_sym_count
4391 * sizeof (Elf_Internal_Sym)));
4392 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4393 finfo.sections = ((asection **)
4394 bfd_malloc (max_sym_count * sizeof (asection *)));
4395 if ((finfo.contents == NULL && max_contents_size != 0)
4396 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4397 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4398 || (finfo.external_syms == NULL && max_sym_count != 0)
4399 || (finfo.internal_syms == NULL && max_sym_count != 0)
4400 || (finfo.indices == NULL && max_sym_count != 0)
4401 || (finfo.sections == NULL && max_sym_count != 0))
4402 goto error_return;
4404 /* Since ELF permits relocations to be against local symbols, we
4405 must have the local symbols available when we do the relocations.
4406 Since we would rather only read the local symbols once, and we
4407 would rather not keep them in memory, we handle all the
4408 relocations for a single input file at the same time.
4410 Unfortunately, there is no way to know the total number of local
4411 symbols until we have seen all of them, and the local symbol
4412 indices precede the global symbol indices. This means that when
4413 we are generating relocateable output, and we see a reloc against
4414 a global symbol, we can not know the symbol index until we have
4415 finished examining all the local symbols to see which ones we are
4416 going to output. To deal with this, we keep the relocations in
4417 memory, and don't output them until the end of the link. This is
4418 an unfortunate waste of memory, but I don't see a good way around
4419 it. Fortunately, it only happens when performing a relocateable
4420 link, which is not the common case. FIXME: If keep_memory is set
4421 we could write the relocs out and then read them again; I don't
4422 know how bad the memory loss will be. */
4424 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4425 sub->output_has_begun = false;
4426 for (o = abfd->sections; o != NULL; o = o->next)
4428 for (p = o->link_order_head; p != NULL; p = p->next)
4430 if (p->type == bfd_indirect_link_order
4431 && (bfd_get_flavour (p->u.indirect.section->owner)
4432 == bfd_target_elf_flavour))
4434 sub = p->u.indirect.section->owner;
4435 if (! sub->output_has_begun)
4437 if (! elf_link_input_bfd (&finfo, sub))
4438 goto error_return;
4439 sub->output_has_begun = true;
4442 else if (p->type == bfd_section_reloc_link_order
4443 || p->type == bfd_symbol_reloc_link_order)
4445 if (! elf_reloc_link_order (abfd, info, o, p))
4446 goto error_return;
4448 else
4450 if (! _bfd_default_link_order (abfd, info, o, p))
4451 goto error_return;
4456 /* That wrote out all the local symbols. Finish up the symbol table
4457 with the global symbols. */
4459 if (info->strip != strip_all && info->shared)
4461 /* Output any global symbols that got converted to local in a
4462 version script. We do this in a separate step since ELF
4463 requires all local symbols to appear prior to any global
4464 symbols. FIXME: We should only do this if some global
4465 symbols were, in fact, converted to become local. FIXME:
4466 Will this work correctly with the Irix 5 linker? */
4467 eoinfo.failed = false;
4468 eoinfo.finfo = &finfo;
4469 eoinfo.localsyms = true;
4470 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4471 (PTR) &eoinfo);
4472 if (eoinfo.failed)
4473 return false;
4476 /* The sh_info field records the index of the first non local symbol. */
4477 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4479 if (dynamic)
4481 Elf_Internal_Sym sym;
4482 Elf_External_Sym *dynsym =
4483 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4484 long last_local = 0;
4486 /* Write out the section symbols for the output sections. */
4487 if (info->shared)
4489 asection *s;
4491 sym.st_size = 0;
4492 sym.st_name = 0;
4493 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4494 sym.st_other = 0;
4496 for (s = abfd->sections; s != NULL; s = s->next)
4498 int indx;
4499 indx = elf_section_data (s)->this_idx;
4500 BFD_ASSERT (indx > 0);
4501 sym.st_shndx = indx;
4502 sym.st_value = s->vma;
4504 elf_swap_symbol_out (abfd, &sym,
4505 dynsym + elf_section_data (s)->dynindx);
4508 last_local = bfd_count_sections (abfd);
4511 /* Write out the local dynsyms. */
4512 if (elf_hash_table (info)->dynlocal)
4514 struct elf_link_local_dynamic_entry *e;
4515 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4517 asection *s;
4519 sym.st_size = e->isym.st_size;
4520 sym.st_other = e->isym.st_other;
4522 /* Copy the internal symbol as is.
4523 Note that we saved a word of storage and overwrote
4524 the original st_name with the dynstr_index. */
4525 sym = e->isym;
4527 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4529 s = bfd_section_from_elf_index (e->input_bfd,
4530 e->isym.st_shndx);
4532 sym.st_shndx =
4533 elf_section_data (s->output_section)->this_idx;
4534 sym.st_value = (s->output_section->vma
4535 + s->output_offset
4536 + e->isym.st_value);
4539 if (last_local < e->dynindx)
4540 last_local = e->dynindx;
4542 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4546 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4547 last_local + 1;
4550 /* We get the global symbols from the hash table. */
4551 eoinfo.failed = false;
4552 eoinfo.localsyms = false;
4553 eoinfo.finfo = &finfo;
4554 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4555 (PTR) &eoinfo);
4556 if (eoinfo.failed)
4557 return false;
4559 /* If backend needs to output some symbols not present in the hash
4560 table, do it now. */
4561 if (bed->elf_backend_output_arch_syms)
4563 if (! (*bed->elf_backend_output_arch_syms)
4564 (abfd, info, (PTR) &finfo,
4565 (boolean (*) PARAMS ((PTR, const char *,
4566 Elf_Internal_Sym *, asection *)))
4567 elf_link_output_sym))
4568 return false;
4571 /* Flush all symbols to the file. */
4572 if (! elf_link_flush_output_syms (&finfo))
4573 return false;
4575 /* Now we know the size of the symtab section. */
4576 off += symtab_hdr->sh_size;
4578 /* Finish up and write out the symbol string table (.strtab)
4579 section. */
4580 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4581 /* sh_name was set in prep_headers. */
4582 symstrtab_hdr->sh_type = SHT_STRTAB;
4583 symstrtab_hdr->sh_flags = 0;
4584 symstrtab_hdr->sh_addr = 0;
4585 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4586 symstrtab_hdr->sh_entsize = 0;
4587 symstrtab_hdr->sh_link = 0;
4588 symstrtab_hdr->sh_info = 0;
4589 /* sh_offset is set just below. */
4590 symstrtab_hdr->sh_addralign = 1;
4592 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4593 elf_tdata (abfd)->next_file_pos = off;
4595 if (bfd_get_symcount (abfd) > 0)
4597 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4598 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4599 return false;
4602 /* Adjust the relocs to have the correct symbol indices. */
4603 for (o = abfd->sections; o != NULL; o = o->next)
4605 if ((o->flags & SEC_RELOC) == 0)
4606 continue;
4608 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4609 elf_section_data (o)->rel_count,
4610 elf_section_data (o)->rel_hashes);
4611 if (elf_section_data (o)->rel_hdr2 != NULL)
4612 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4613 elf_section_data (o)->rel_count2,
4614 (elf_section_data (o)->rel_hashes
4615 + elf_section_data (o)->rel_count));
4617 /* Set the reloc_count field to 0 to prevent write_relocs from
4618 trying to swap the relocs out itself. */
4619 o->reloc_count = 0;
4622 /* If we are linking against a dynamic object, or generating a
4623 shared library, finish up the dynamic linking information. */
4624 if (dynamic)
4626 Elf_External_Dyn *dyncon, *dynconend;
4628 /* Fix up .dynamic entries. */
4629 o = bfd_get_section_by_name (dynobj, ".dynamic");
4630 BFD_ASSERT (o != NULL);
4632 dyncon = (Elf_External_Dyn *) o->contents;
4633 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4634 for (; dyncon < dynconend; dyncon++)
4636 Elf_Internal_Dyn dyn;
4637 const char *name;
4638 unsigned int type;
4640 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4642 switch (dyn.d_tag)
4644 default:
4645 break;
4646 case DT_INIT:
4647 name = info->init_function;
4648 goto get_sym;
4649 case DT_FINI:
4650 name = info->fini_function;
4651 get_sym:
4653 struct elf_link_hash_entry *h;
4655 h = elf_link_hash_lookup (elf_hash_table (info), name,
4656 false, false, true);
4657 if (h != NULL
4658 && (h->root.type == bfd_link_hash_defined
4659 || h->root.type == bfd_link_hash_defweak))
4661 dyn.d_un.d_val = h->root.u.def.value;
4662 o = h->root.u.def.section;
4663 if (o->output_section != NULL)
4664 dyn.d_un.d_val += (o->output_section->vma
4665 + o->output_offset);
4666 else
4668 /* The symbol is imported from another shared
4669 library and does not apply to this one. */
4670 dyn.d_un.d_val = 0;
4673 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4676 break;
4678 case DT_HASH:
4679 name = ".hash";
4680 goto get_vma;
4681 case DT_STRTAB:
4682 name = ".dynstr";
4683 goto get_vma;
4684 case DT_SYMTAB:
4685 name = ".dynsym";
4686 goto get_vma;
4687 case DT_VERDEF:
4688 name = ".gnu.version_d";
4689 goto get_vma;
4690 case DT_VERNEED:
4691 name = ".gnu.version_r";
4692 goto get_vma;
4693 case DT_VERSYM:
4694 name = ".gnu.version";
4695 get_vma:
4696 o = bfd_get_section_by_name (abfd, name);
4697 BFD_ASSERT (o != NULL);
4698 dyn.d_un.d_ptr = o->vma;
4699 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4700 break;
4702 case DT_REL:
4703 case DT_RELA:
4704 case DT_RELSZ:
4705 case DT_RELASZ:
4706 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4707 type = SHT_REL;
4708 else
4709 type = SHT_RELA;
4710 dyn.d_un.d_val = 0;
4711 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4713 Elf_Internal_Shdr *hdr;
4715 hdr = elf_elfsections (abfd)[i];
4716 if (hdr->sh_type == type
4717 && (hdr->sh_flags & SHF_ALLOC) != 0)
4719 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4720 dyn.d_un.d_val += hdr->sh_size;
4721 else
4723 if (dyn.d_un.d_val == 0
4724 || hdr->sh_addr < dyn.d_un.d_val)
4725 dyn.d_un.d_val = hdr->sh_addr;
4729 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4730 break;
4735 /* If we have created any dynamic sections, then output them. */
4736 if (dynobj != NULL)
4738 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4739 goto error_return;
4741 for (o = dynobj->sections; o != NULL; o = o->next)
4743 if ((o->flags & SEC_HAS_CONTENTS) == 0
4744 || o->_raw_size == 0)
4745 continue;
4746 if ((o->flags & SEC_LINKER_CREATED) == 0)
4748 /* At this point, we are only interested in sections
4749 created by elf_link_create_dynamic_sections. */
4750 continue;
4752 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4753 != SHT_STRTAB)
4754 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4756 if (! bfd_set_section_contents (abfd, o->output_section,
4757 o->contents, o->output_offset,
4758 o->_raw_size))
4759 goto error_return;
4761 else
4763 file_ptr off;
4765 /* The contents of the .dynstr section are actually in a
4766 stringtab. */
4767 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4768 if (bfd_seek (abfd, off, SEEK_SET) != 0
4769 || ! _bfd_stringtab_emit (abfd,
4770 elf_hash_table (info)->dynstr))
4771 goto error_return;
4776 /* If we have optimized stabs strings, output them. */
4777 if (elf_hash_table (info)->stab_info != NULL)
4779 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4780 goto error_return;
4783 if (finfo.symstrtab != NULL)
4784 _bfd_stringtab_free (finfo.symstrtab);
4785 if (finfo.contents != NULL)
4786 free (finfo.contents);
4787 if (finfo.external_relocs != NULL)
4788 free (finfo.external_relocs);
4789 if (finfo.internal_relocs != NULL)
4790 free (finfo.internal_relocs);
4791 if (finfo.external_syms != NULL)
4792 free (finfo.external_syms);
4793 if (finfo.internal_syms != NULL)
4794 free (finfo.internal_syms);
4795 if (finfo.indices != NULL)
4796 free (finfo.indices);
4797 if (finfo.sections != NULL)
4798 free (finfo.sections);
4799 if (finfo.symbuf != NULL)
4800 free (finfo.symbuf);
4801 for (o = abfd->sections; o != NULL; o = o->next)
4803 if ((o->flags & SEC_RELOC) != 0
4804 && elf_section_data (o)->rel_hashes != NULL)
4805 free (elf_section_data (o)->rel_hashes);
4808 elf_tdata (abfd)->linker = true;
4810 return true;
4812 error_return:
4813 if (finfo.symstrtab != NULL)
4814 _bfd_stringtab_free (finfo.symstrtab);
4815 if (finfo.contents != NULL)
4816 free (finfo.contents);
4817 if (finfo.external_relocs != NULL)
4818 free (finfo.external_relocs);
4819 if (finfo.internal_relocs != NULL)
4820 free (finfo.internal_relocs);
4821 if (finfo.external_syms != NULL)
4822 free (finfo.external_syms);
4823 if (finfo.internal_syms != NULL)
4824 free (finfo.internal_syms);
4825 if (finfo.indices != NULL)
4826 free (finfo.indices);
4827 if (finfo.sections != NULL)
4828 free (finfo.sections);
4829 if (finfo.symbuf != NULL)
4830 free (finfo.symbuf);
4831 for (o = abfd->sections; o != NULL; o = o->next)
4833 if ((o->flags & SEC_RELOC) != 0
4834 && elf_section_data (o)->rel_hashes != NULL)
4835 free (elf_section_data (o)->rel_hashes);
4838 return false;
4841 /* Add a symbol to the output symbol table. */
4843 static boolean
4844 elf_link_output_sym (finfo, name, elfsym, input_sec)
4845 struct elf_final_link_info *finfo;
4846 const char *name;
4847 Elf_Internal_Sym *elfsym;
4848 asection *input_sec;
4850 boolean (*output_symbol_hook) PARAMS ((bfd *,
4851 struct bfd_link_info *info,
4852 const char *,
4853 Elf_Internal_Sym *,
4854 asection *));
4856 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4857 elf_backend_link_output_symbol_hook;
4858 if (output_symbol_hook != NULL)
4860 if (! ((*output_symbol_hook)
4861 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4862 return false;
4865 if (name == (const char *) NULL || *name == '\0')
4866 elfsym->st_name = 0;
4867 else if (input_sec->flags & SEC_EXCLUDE)
4868 elfsym->st_name = 0;
4869 else
4871 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4872 name, true,
4873 false);
4874 if (elfsym->st_name == (unsigned long) -1)
4875 return false;
4878 if (finfo->symbuf_count >= finfo->symbuf_size)
4880 if (! elf_link_flush_output_syms (finfo))
4881 return false;
4884 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4885 (PTR) (finfo->symbuf + finfo->symbuf_count));
4886 ++finfo->symbuf_count;
4888 ++ bfd_get_symcount (finfo->output_bfd);
4890 return true;
4893 /* Flush the output symbols to the file. */
4895 static boolean
4896 elf_link_flush_output_syms (finfo)
4897 struct elf_final_link_info *finfo;
4899 if (finfo->symbuf_count > 0)
4901 Elf_Internal_Shdr *symtab;
4903 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4905 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4906 SEEK_SET) != 0
4907 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4908 sizeof (Elf_External_Sym), finfo->output_bfd)
4909 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4910 return false;
4912 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4914 finfo->symbuf_count = 0;
4917 return true;
4920 /* Add an external symbol to the symbol table. This is called from
4921 the hash table traversal routine. When generating a shared object,
4922 we go through the symbol table twice. The first time we output
4923 anything that might have been forced to local scope in a version
4924 script. The second time we output the symbols that are still
4925 global symbols. */
4927 static boolean
4928 elf_link_output_extsym (h, data)
4929 struct elf_link_hash_entry *h;
4930 PTR data;
4932 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4933 struct elf_final_link_info *finfo = eoinfo->finfo;
4934 boolean strip;
4935 Elf_Internal_Sym sym;
4936 asection *input_sec;
4938 /* Decide whether to output this symbol in this pass. */
4939 if (eoinfo->localsyms)
4941 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4942 return true;
4944 else
4946 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4947 return true;
4950 /* If we are not creating a shared library, and this symbol is
4951 referenced by a shared library but is not defined anywhere, then
4952 warn that it is undefined. If we do not do this, the runtime
4953 linker will complain that the symbol is undefined when the
4954 program is run. We don't have to worry about symbols that are
4955 referenced by regular files, because we will already have issued
4956 warnings for them. */
4957 if (! finfo->info->relocateable
4958 && ! (finfo->info->shared
4959 && !finfo->info->no_undefined)
4960 && h->root.type == bfd_link_hash_undefined
4961 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4962 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4964 if (! ((*finfo->info->callbacks->undefined_symbol)
4965 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4966 (asection *) NULL, 0)))
4968 eoinfo->failed = true;
4969 return false;
4973 /* We don't want to output symbols that have never been mentioned by
4974 a regular file, or that we have been told to strip. However, if
4975 h->indx is set to -2, the symbol is used by a reloc and we must
4976 output it. */
4977 if (h->indx == -2)
4978 strip = false;
4979 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4980 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4981 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4982 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4983 strip = true;
4984 else if (finfo->info->strip == strip_all
4985 || (finfo->info->strip == strip_some
4986 && bfd_hash_lookup (finfo->info->keep_hash,
4987 h->root.root.string,
4988 false, false) == NULL))
4989 strip = true;
4990 else
4991 strip = false;
4993 /* If we're stripping it, and it's not a dynamic symbol, there's
4994 nothing else to do. */
4995 if (strip && h->dynindx == -1)
4996 return true;
4998 sym.st_value = 0;
4999 sym.st_size = h->size;
5000 sym.st_other = h->other;
5001 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5002 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5003 else if (h->root.type == bfd_link_hash_undefweak
5004 || h->root.type == bfd_link_hash_defweak)
5005 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5006 else
5007 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5009 switch (h->root.type)
5011 default:
5012 case bfd_link_hash_new:
5013 abort ();
5014 return false;
5016 case bfd_link_hash_undefined:
5017 input_sec = bfd_und_section_ptr;
5018 sym.st_shndx = SHN_UNDEF;
5019 break;
5021 case bfd_link_hash_undefweak:
5022 input_sec = bfd_und_section_ptr;
5023 sym.st_shndx = SHN_UNDEF;
5024 break;
5026 case bfd_link_hash_defined:
5027 case bfd_link_hash_defweak:
5029 input_sec = h->root.u.def.section;
5030 if (input_sec->output_section != NULL)
5032 sym.st_shndx =
5033 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5034 input_sec->output_section);
5035 if (sym.st_shndx == (unsigned short) -1)
5037 (*_bfd_error_handler)
5038 (_("%s: could not find output section %s for input section %s"),
5039 bfd_get_filename (finfo->output_bfd),
5040 input_sec->output_section->name,
5041 input_sec->name);
5042 eoinfo->failed = true;
5043 return false;
5046 /* ELF symbols in relocateable files are section relative,
5047 but in nonrelocateable files they are virtual
5048 addresses. */
5049 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5050 if (! finfo->info->relocateable)
5051 sym.st_value += input_sec->output_section->vma;
5053 else
5055 BFD_ASSERT (input_sec->owner == NULL
5056 || (input_sec->owner->flags & DYNAMIC) != 0);
5057 sym.st_shndx = SHN_UNDEF;
5058 input_sec = bfd_und_section_ptr;
5061 break;
5063 case bfd_link_hash_common:
5064 input_sec = h->root.u.c.p->section;
5065 sym.st_shndx = SHN_COMMON;
5066 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5067 break;
5069 case bfd_link_hash_indirect:
5070 /* These symbols are created by symbol versioning. They point
5071 to the decorated version of the name. For example, if the
5072 symbol foo@@GNU_1.2 is the default, which should be used when
5073 foo is used with no version, then we add an indirect symbol
5074 foo which points to foo@@GNU_1.2. We ignore these symbols,
5075 since the indirected symbol is already in the hash table. If
5076 the indirect symbol is non-ELF, fall through and output it. */
5077 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
5078 return true;
5080 /* Fall through. */
5081 case bfd_link_hash_warning:
5082 /* We can't represent these symbols in ELF, although a warning
5083 symbol may have come from a .gnu.warning.SYMBOL section. We
5084 just put the target symbol in the hash table. If the target
5085 symbol does not really exist, don't do anything. */
5086 if (h->root.u.i.link->type == bfd_link_hash_new)
5087 return true;
5088 return (elf_link_output_extsym
5089 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5092 /* Give the processor backend a chance to tweak the symbol value,
5093 and also to finish up anything that needs to be done for this
5094 symbol. */
5095 if ((h->dynindx != -1
5096 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5097 && elf_hash_table (finfo->info)->dynamic_sections_created)
5099 struct elf_backend_data *bed;
5101 bed = get_elf_backend_data (finfo->output_bfd);
5102 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5103 (finfo->output_bfd, finfo->info, h, &sym)))
5105 eoinfo->failed = true;
5106 return false;
5110 /* If we are marking the symbol as undefined, and there are no
5111 non-weak references to this symbol from a regular object, then
5112 mark the symbol as weak undefined; if there are non-weak
5113 references, mark the symbol as strong. We can't do this earlier,
5114 because it might not be marked as undefined until the
5115 finish_dynamic_symbol routine gets through with it. */
5116 if (sym.st_shndx == SHN_UNDEF
5117 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5118 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5119 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5121 int bindtype;
5123 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5124 bindtype = STB_GLOBAL;
5125 else
5126 bindtype = STB_WEAK;
5127 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5130 /* If this symbol should be put in the .dynsym section, then put it
5131 there now. We have already know the symbol index. We also fill
5132 in the entry in the .hash section. */
5133 if (h->dynindx != -1
5134 && elf_hash_table (finfo->info)->dynamic_sections_created)
5136 size_t bucketcount;
5137 size_t bucket;
5138 size_t hash_entry_size;
5139 bfd_byte *bucketpos;
5140 bfd_vma chain;
5142 sym.st_name = h->dynstr_index;
5144 elf_swap_symbol_out (finfo->output_bfd, &sym,
5145 (PTR) (((Elf_External_Sym *)
5146 finfo->dynsym_sec->contents)
5147 + h->dynindx));
5149 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5150 bucket = h->elf_hash_value % bucketcount;
5151 hash_entry_size
5152 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5153 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5154 + (bucket + 2) * hash_entry_size);
5155 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5156 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5157 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5158 ((bfd_byte *) finfo->hash_sec->contents
5159 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5161 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5163 Elf_Internal_Versym iversym;
5165 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5167 if (h->verinfo.verdef == NULL)
5168 iversym.vs_vers = 0;
5169 else
5170 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5172 else
5174 if (h->verinfo.vertree == NULL)
5175 iversym.vs_vers = 1;
5176 else
5177 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5180 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5181 iversym.vs_vers |= VERSYM_HIDDEN;
5183 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5184 (((Elf_External_Versym *)
5185 finfo->symver_sec->contents)
5186 + h->dynindx));
5190 /* If we're stripping it, then it was just a dynamic symbol, and
5191 there's nothing else to do. */
5192 if (strip)
5193 return true;
5195 h->indx = bfd_get_symcount (finfo->output_bfd);
5197 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5199 eoinfo->failed = true;
5200 return false;
5203 return true;
5206 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5207 originated from the section given by INPUT_REL_HDR) to the
5208 OUTPUT_BFD. */
5210 static void
5211 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5212 internal_relocs)
5213 bfd *output_bfd;
5214 asection *input_section;
5215 Elf_Internal_Shdr *input_rel_hdr;
5216 Elf_Internal_Rela *internal_relocs;
5218 Elf_Internal_Rela *irela;
5219 Elf_Internal_Rela *irelaend;
5220 Elf_Internal_Shdr *output_rel_hdr;
5221 asection *output_section;
5222 unsigned int *rel_countp = NULL;
5224 output_section = input_section->output_section;
5225 output_rel_hdr = NULL;
5227 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5228 == input_rel_hdr->sh_entsize)
5230 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5231 rel_countp = &elf_section_data (output_section)->rel_count;
5233 else if (elf_section_data (output_section)->rel_hdr2
5234 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5235 == input_rel_hdr->sh_entsize))
5237 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5238 rel_countp = &elf_section_data (output_section)->rel_count2;
5241 BFD_ASSERT (output_rel_hdr != NULL);
5243 irela = internal_relocs;
5244 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5245 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5247 Elf_External_Rel *erel;
5249 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5250 for (; irela < irelaend; irela++, erel++)
5252 Elf_Internal_Rel irel;
5254 irel.r_offset = irela->r_offset;
5255 irel.r_info = irela->r_info;
5256 BFD_ASSERT (irela->r_addend == 0);
5257 elf_swap_reloc_out (output_bfd, &irel, erel);
5260 else
5262 Elf_External_Rela *erela;
5264 BFD_ASSERT (input_rel_hdr->sh_entsize
5265 == sizeof (Elf_External_Rela));
5266 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5267 for (; irela < irelaend; irela++, erela++)
5268 elf_swap_reloca_out (output_bfd, irela, erela);
5271 /* Bump the counter, so that we know where to add the next set of
5272 relocations. */
5273 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5276 /* Link an input file into the linker output file. This function
5277 handles all the sections and relocations of the input file at once.
5278 This is so that we only have to read the local symbols once, and
5279 don't have to keep them in memory. */
5281 static boolean
5282 elf_link_input_bfd (finfo, input_bfd)
5283 struct elf_final_link_info *finfo;
5284 bfd *input_bfd;
5286 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5287 bfd *, asection *, bfd_byte *,
5288 Elf_Internal_Rela *,
5289 Elf_Internal_Sym *, asection **));
5290 bfd *output_bfd;
5291 Elf_Internal_Shdr *symtab_hdr;
5292 size_t locsymcount;
5293 size_t extsymoff;
5294 Elf_External_Sym *external_syms;
5295 Elf_External_Sym *esym;
5296 Elf_External_Sym *esymend;
5297 Elf_Internal_Sym *isym;
5298 long *pindex;
5299 asection **ppsection;
5300 asection *o;
5301 struct elf_backend_data *bed;
5303 output_bfd = finfo->output_bfd;
5304 bed = get_elf_backend_data (output_bfd);
5305 relocate_section = bed->elf_backend_relocate_section;
5307 /* If this is a dynamic object, we don't want to do anything here:
5308 we don't want the local symbols, and we don't want the section
5309 contents. */
5310 if ((input_bfd->flags & DYNAMIC) != 0)
5311 return true;
5313 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5314 if (elf_bad_symtab (input_bfd))
5316 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5317 extsymoff = 0;
5319 else
5321 locsymcount = symtab_hdr->sh_info;
5322 extsymoff = symtab_hdr->sh_info;
5325 /* Read the local symbols. */
5326 if (symtab_hdr->contents != NULL)
5327 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5328 else if (locsymcount == 0)
5329 external_syms = NULL;
5330 else
5332 external_syms = finfo->external_syms;
5333 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5334 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5335 locsymcount, input_bfd)
5336 != locsymcount * sizeof (Elf_External_Sym)))
5337 return false;
5340 /* Swap in the local symbols and write out the ones which we know
5341 are going into the output file. */
5342 esym = external_syms;
5343 esymend = esym + locsymcount;
5344 isym = finfo->internal_syms;
5345 pindex = finfo->indices;
5346 ppsection = finfo->sections;
5347 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5349 asection *isec;
5350 const char *name;
5351 Elf_Internal_Sym osym;
5353 elf_swap_symbol_in (input_bfd, esym, isym);
5354 *pindex = -1;
5356 if (elf_bad_symtab (input_bfd))
5358 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5360 *ppsection = NULL;
5361 continue;
5365 if (isym->st_shndx == SHN_UNDEF)
5366 isec = bfd_und_section_ptr;
5367 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5368 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5369 else if (isym->st_shndx == SHN_ABS)
5370 isec = bfd_abs_section_ptr;
5371 else if (isym->st_shndx == SHN_COMMON)
5372 isec = bfd_com_section_ptr;
5373 else
5375 /* Who knows? */
5376 isec = NULL;
5379 *ppsection = isec;
5381 /* Don't output the first, undefined, symbol. */
5382 if (esym == external_syms)
5383 continue;
5385 /* If we are stripping all symbols, we don't want to output this
5386 one. */
5387 if (finfo->info->strip == strip_all)
5388 continue;
5390 /* We never output section symbols. Instead, we use the section
5391 symbol of the corresponding section in the output file. */
5392 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5393 continue;
5395 /* If we are discarding all local symbols, we don't want to
5396 output this one. If we are generating a relocateable output
5397 file, then some of the local symbols may be required by
5398 relocs; we output them below as we discover that they are
5399 needed. */
5400 if (finfo->info->discard == discard_all)
5401 continue;
5403 /* If this symbol is defined in a section which we are
5404 discarding, we don't need to keep it, but note that
5405 linker_mark is only reliable for sections that have contents.
5406 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5407 as well as linker_mark. */
5408 if (isym->st_shndx > 0
5409 && isym->st_shndx < SHN_LORESERVE
5410 && isec != NULL
5411 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5412 || (! finfo->info->relocateable
5413 && (isec->flags & SEC_EXCLUDE) != 0)))
5414 continue;
5416 /* Get the name of the symbol. */
5417 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5418 isym->st_name);
5419 if (name == NULL)
5420 return false;
5422 /* See if we are discarding symbols with this name. */
5423 if ((finfo->info->strip == strip_some
5424 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5425 == NULL))
5426 || (finfo->info->discard == discard_l
5427 && bfd_is_local_label_name (input_bfd, name)))
5428 continue;
5430 /* If we get here, we are going to output this symbol. */
5432 osym = *isym;
5434 /* Adjust the section index for the output file. */
5435 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5436 isec->output_section);
5437 if (osym.st_shndx == (unsigned short) -1)
5438 return false;
5440 *pindex = bfd_get_symcount (output_bfd);
5442 /* ELF symbols in relocateable files are section relative, but
5443 in executable files they are virtual addresses. Note that
5444 this code assumes that all ELF sections have an associated
5445 BFD section with a reasonable value for output_offset; below
5446 we assume that they also have a reasonable value for
5447 output_section. Any special sections must be set up to meet
5448 these requirements. */
5449 osym.st_value += isec->output_offset;
5450 if (! finfo->info->relocateable)
5451 osym.st_value += isec->output_section->vma;
5453 if (! elf_link_output_sym (finfo, name, &osym, isec))
5454 return false;
5457 /* Relocate the contents of each section. */
5458 for (o = input_bfd->sections; o != NULL; o = o->next)
5460 bfd_byte *contents;
5462 if (! o->linker_mark)
5464 /* This section was omitted from the link. */
5465 continue;
5468 if ((o->flags & SEC_HAS_CONTENTS) == 0
5469 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5470 continue;
5472 if ((o->flags & SEC_LINKER_CREATED) != 0)
5474 /* Section was created by elf_link_create_dynamic_sections
5475 or somesuch. */
5476 continue;
5479 /* Get the contents of the section. They have been cached by a
5480 relaxation routine. Note that o is a section in an input
5481 file, so the contents field will not have been set by any of
5482 the routines which work on output files. */
5483 if (elf_section_data (o)->this_hdr.contents != NULL)
5484 contents = elf_section_data (o)->this_hdr.contents;
5485 else
5487 contents = finfo->contents;
5488 if (! bfd_get_section_contents (input_bfd, o, contents,
5489 (file_ptr) 0, o->_raw_size))
5490 return false;
5493 if ((o->flags & SEC_RELOC) != 0)
5495 Elf_Internal_Rela *internal_relocs;
5497 /* Get the swapped relocs. */
5498 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5499 (input_bfd, o, finfo->external_relocs,
5500 finfo->internal_relocs, false));
5501 if (internal_relocs == NULL
5502 && o->reloc_count > 0)
5503 return false;
5505 /* Relocate the section by invoking a back end routine.
5507 The back end routine is responsible for adjusting the
5508 section contents as necessary, and (if using Rela relocs
5509 and generating a relocateable output file) adjusting the
5510 reloc addend as necessary.
5512 The back end routine does not have to worry about setting
5513 the reloc address or the reloc symbol index.
5515 The back end routine is given a pointer to the swapped in
5516 internal symbols, and can access the hash table entries
5517 for the external symbols via elf_sym_hashes (input_bfd).
5519 When generating relocateable output, the back end routine
5520 must handle STB_LOCAL/STT_SECTION symbols specially. The
5521 output symbol is going to be a section symbol
5522 corresponding to the output section, which will require
5523 the addend to be adjusted. */
5525 if (! (*relocate_section) (output_bfd, finfo->info,
5526 input_bfd, o, contents,
5527 internal_relocs,
5528 finfo->internal_syms,
5529 finfo->sections))
5530 return false;
5532 if (finfo->info->relocateable)
5534 Elf_Internal_Rela *irela;
5535 Elf_Internal_Rela *irelaend;
5536 struct elf_link_hash_entry **rel_hash;
5537 Elf_Internal_Shdr *input_rel_hdr;
5539 /* Adjust the reloc addresses and symbol indices. */
5541 irela = internal_relocs;
5542 irelaend =
5543 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5544 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5545 + elf_section_data (o->output_section)->rel_count
5546 + elf_section_data (o->output_section)->rel_count2);
5547 for (; irela < irelaend; irela++, rel_hash++)
5549 unsigned long r_symndx;
5550 Elf_Internal_Sym *isym;
5551 asection *sec;
5553 irela->r_offset += o->output_offset;
5555 r_symndx = ELF_R_SYM (irela->r_info);
5557 if (r_symndx == 0)
5558 continue;
5560 if (r_symndx >= locsymcount
5561 || (elf_bad_symtab (input_bfd)
5562 && finfo->sections[r_symndx] == NULL))
5564 struct elf_link_hash_entry *rh;
5565 long indx;
5567 /* This is a reloc against a global symbol. We
5568 have not yet output all the local symbols, so
5569 we do not know the symbol index of any global
5570 symbol. We set the rel_hash entry for this
5571 reloc to point to the global hash table entry
5572 for this symbol. The symbol index is then
5573 set at the end of elf_bfd_final_link. */
5574 indx = r_symndx - extsymoff;
5575 rh = elf_sym_hashes (input_bfd)[indx];
5576 while (rh->root.type == bfd_link_hash_indirect
5577 || rh->root.type == bfd_link_hash_warning)
5578 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5580 /* Setting the index to -2 tells
5581 elf_link_output_extsym that this symbol is
5582 used by a reloc. */
5583 BFD_ASSERT (rh->indx < 0);
5584 rh->indx = -2;
5586 *rel_hash = rh;
5588 continue;
5591 /* This is a reloc against a local symbol. */
5593 *rel_hash = NULL;
5594 isym = finfo->internal_syms + r_symndx;
5595 sec = finfo->sections[r_symndx];
5596 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5598 /* I suppose the backend ought to fill in the
5599 section of any STT_SECTION symbol against a
5600 processor specific section. If we have
5601 discarded a section, the output_section will
5602 be the absolute section. */
5603 if (sec != NULL
5604 && (bfd_is_abs_section (sec)
5605 || (sec->output_section != NULL
5606 && bfd_is_abs_section (sec->output_section))))
5607 r_symndx = 0;
5608 else if (sec == NULL || sec->owner == NULL)
5610 bfd_set_error (bfd_error_bad_value);
5611 return false;
5613 else
5615 r_symndx = sec->output_section->target_index;
5616 BFD_ASSERT (r_symndx != 0);
5619 else
5621 if (finfo->indices[r_symndx] == -1)
5623 unsigned long link;
5624 const char *name;
5625 asection *osec;
5627 if (finfo->info->strip == strip_all)
5629 /* You can't do ld -r -s. */
5630 bfd_set_error (bfd_error_invalid_operation);
5631 return false;
5634 /* This symbol was skipped earlier, but
5635 since it is needed by a reloc, we
5636 must output it now. */
5637 link = symtab_hdr->sh_link;
5638 name = bfd_elf_string_from_elf_section (input_bfd,
5639 link,
5640 isym->st_name);
5641 if (name == NULL)
5642 return false;
5644 osec = sec->output_section;
5645 isym->st_shndx =
5646 _bfd_elf_section_from_bfd_section (output_bfd,
5647 osec);
5648 if (isym->st_shndx == (unsigned short) -1)
5649 return false;
5651 isym->st_value += sec->output_offset;
5652 if (! finfo->info->relocateable)
5653 isym->st_value += osec->vma;
5655 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5657 if (! elf_link_output_sym (finfo, name, isym, sec))
5658 return false;
5661 r_symndx = finfo->indices[r_symndx];
5664 irela->r_info = ELF_R_INFO (r_symndx,
5665 ELF_R_TYPE (irela->r_info));
5668 /* Swap out the relocs. */
5669 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5670 elf_link_output_relocs (output_bfd, o,
5671 input_rel_hdr,
5672 internal_relocs);
5673 internal_relocs
5674 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5675 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5676 if (input_rel_hdr)
5677 elf_link_output_relocs (output_bfd, o,
5678 input_rel_hdr,
5679 internal_relocs);
5683 /* Write out the modified section contents. */
5684 if (elf_section_data (o)->stab_info == NULL)
5686 if (! (o->flags & SEC_EXCLUDE) &&
5687 ! bfd_set_section_contents (output_bfd, o->output_section,
5688 contents, o->output_offset,
5689 (o->_cooked_size != 0
5690 ? o->_cooked_size
5691 : o->_raw_size)))
5692 return false;
5694 else
5696 if (! (_bfd_write_section_stabs
5697 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5698 o, &elf_section_data (o)->stab_info, contents)))
5699 return false;
5703 return true;
5706 /* Generate a reloc when linking an ELF file. This is a reloc
5707 requested by the linker, and does come from any input file. This
5708 is used to build constructor and destructor tables when linking
5709 with -Ur. */
5711 static boolean
5712 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5713 bfd *output_bfd;
5714 struct bfd_link_info *info;
5715 asection *output_section;
5716 struct bfd_link_order *link_order;
5718 reloc_howto_type *howto;
5719 long indx;
5720 bfd_vma offset;
5721 bfd_vma addend;
5722 struct elf_link_hash_entry **rel_hash_ptr;
5723 Elf_Internal_Shdr *rel_hdr;
5725 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5726 if (howto == NULL)
5728 bfd_set_error (bfd_error_bad_value);
5729 return false;
5732 addend = link_order->u.reloc.p->addend;
5734 /* Figure out the symbol index. */
5735 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5736 + elf_section_data (output_section)->rel_count
5737 + elf_section_data (output_section)->rel_count2);
5738 if (link_order->type == bfd_section_reloc_link_order)
5740 indx = link_order->u.reloc.p->u.section->target_index;
5741 BFD_ASSERT (indx != 0);
5742 *rel_hash_ptr = NULL;
5744 else
5746 struct elf_link_hash_entry *h;
5748 /* Treat a reloc against a defined symbol as though it were
5749 actually against the section. */
5750 h = ((struct elf_link_hash_entry *)
5751 bfd_wrapped_link_hash_lookup (output_bfd, info,
5752 link_order->u.reloc.p->u.name,
5753 false, false, true));
5754 if (h != NULL
5755 && (h->root.type == bfd_link_hash_defined
5756 || h->root.type == bfd_link_hash_defweak))
5758 asection *section;
5760 section = h->root.u.def.section;
5761 indx = section->output_section->target_index;
5762 *rel_hash_ptr = NULL;
5763 /* It seems that we ought to add the symbol value to the
5764 addend here, but in practice it has already been added
5765 because it was passed to constructor_callback. */
5766 addend += section->output_section->vma + section->output_offset;
5768 else if (h != NULL)
5770 /* Setting the index to -2 tells elf_link_output_extsym that
5771 this symbol is used by a reloc. */
5772 h->indx = -2;
5773 *rel_hash_ptr = h;
5774 indx = 0;
5776 else
5778 if (! ((*info->callbacks->unattached_reloc)
5779 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5780 (asection *) NULL, (bfd_vma) 0)))
5781 return false;
5782 indx = 0;
5786 /* If this is an inplace reloc, we must write the addend into the
5787 object file. */
5788 if (howto->partial_inplace && addend != 0)
5790 bfd_size_type size;
5791 bfd_reloc_status_type rstat;
5792 bfd_byte *buf;
5793 boolean ok;
5795 size = bfd_get_reloc_size (howto);
5796 buf = (bfd_byte *) bfd_zmalloc (size);
5797 if (buf == (bfd_byte *) NULL)
5798 return false;
5799 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5800 switch (rstat)
5802 case bfd_reloc_ok:
5803 break;
5804 default:
5805 case bfd_reloc_outofrange:
5806 abort ();
5807 case bfd_reloc_overflow:
5808 if (! ((*info->callbacks->reloc_overflow)
5809 (info,
5810 (link_order->type == bfd_section_reloc_link_order
5811 ? bfd_section_name (output_bfd,
5812 link_order->u.reloc.p->u.section)
5813 : link_order->u.reloc.p->u.name),
5814 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5815 (bfd_vma) 0)))
5817 free (buf);
5818 return false;
5820 break;
5822 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5823 (file_ptr) link_order->offset, size);
5824 free (buf);
5825 if (! ok)
5826 return false;
5829 /* The address of a reloc is relative to the section in a
5830 relocateable file, and is a virtual address in an executable
5831 file. */
5832 offset = link_order->offset;
5833 if (! info->relocateable)
5834 offset += output_section->vma;
5836 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5838 if (rel_hdr->sh_type == SHT_REL)
5840 Elf_Internal_Rel irel;
5841 Elf_External_Rel *erel;
5843 irel.r_offset = offset;
5844 irel.r_info = ELF_R_INFO (indx, howto->type);
5845 erel = ((Elf_External_Rel *) rel_hdr->contents
5846 + elf_section_data (output_section)->rel_count);
5847 elf_swap_reloc_out (output_bfd, &irel, erel);
5849 else
5851 Elf_Internal_Rela irela;
5852 Elf_External_Rela *erela;
5854 irela.r_offset = offset;
5855 irela.r_info = ELF_R_INFO (indx, howto->type);
5856 irela.r_addend = addend;
5857 erela = ((Elf_External_Rela *) rel_hdr->contents
5858 + elf_section_data (output_section)->rel_count);
5859 elf_swap_reloca_out (output_bfd, &irela, erela);
5862 ++elf_section_data (output_section)->rel_count;
5864 return true;
5868 /* Allocate a pointer to live in a linker created section. */
5870 boolean
5871 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5872 bfd *abfd;
5873 struct bfd_link_info *info;
5874 elf_linker_section_t *lsect;
5875 struct elf_link_hash_entry *h;
5876 const Elf_Internal_Rela *rel;
5878 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5879 elf_linker_section_pointers_t *linker_section_ptr;
5880 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5882 BFD_ASSERT (lsect != NULL);
5884 /* Is this a global symbol? */
5885 if (h != NULL)
5887 /* Has this symbol already been allocated, if so, our work is done */
5888 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5889 rel->r_addend,
5890 lsect->which))
5891 return true;
5893 ptr_linker_section_ptr = &h->linker_section_pointer;
5894 /* Make sure this symbol is output as a dynamic symbol. */
5895 if (h->dynindx == -1)
5897 if (! elf_link_record_dynamic_symbol (info, h))
5898 return false;
5901 if (lsect->rel_section)
5902 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5905 else /* Allocation of a pointer to a local symbol */
5907 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5909 /* Allocate a table to hold the local symbols if first time */
5910 if (!ptr)
5912 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5913 register unsigned int i;
5915 ptr = (elf_linker_section_pointers_t **)
5916 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5918 if (!ptr)
5919 return false;
5921 elf_local_ptr_offsets (abfd) = ptr;
5922 for (i = 0; i < num_symbols; i++)
5923 ptr[i] = (elf_linker_section_pointers_t *)0;
5926 /* Has this symbol already been allocated, if so, our work is done */
5927 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5928 rel->r_addend,
5929 lsect->which))
5930 return true;
5932 ptr_linker_section_ptr = &ptr[r_symndx];
5934 if (info->shared)
5936 /* If we are generating a shared object, we need to
5937 output a R_<xxx>_RELATIVE reloc so that the
5938 dynamic linker can adjust this GOT entry. */
5939 BFD_ASSERT (lsect->rel_section != NULL);
5940 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5944 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5945 from internal memory. */
5946 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5947 linker_section_ptr = (elf_linker_section_pointers_t *)
5948 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5950 if (!linker_section_ptr)
5951 return false;
5953 linker_section_ptr->next = *ptr_linker_section_ptr;
5954 linker_section_ptr->addend = rel->r_addend;
5955 linker_section_ptr->which = lsect->which;
5956 linker_section_ptr->written_address_p = false;
5957 *ptr_linker_section_ptr = linker_section_ptr;
5959 #if 0
5960 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5962 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5963 lsect->hole_offset += ARCH_SIZE / 8;
5964 lsect->sym_offset += ARCH_SIZE / 8;
5965 if (lsect->sym_hash) /* Bump up symbol value if needed */
5967 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5968 #ifdef DEBUG
5969 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5970 lsect->sym_hash->root.root.string,
5971 (long)ARCH_SIZE / 8,
5972 (long)lsect->sym_hash->root.u.def.value);
5973 #endif
5976 else
5977 #endif
5978 linker_section_ptr->offset = lsect->section->_raw_size;
5980 lsect->section->_raw_size += ARCH_SIZE / 8;
5982 #ifdef DEBUG
5983 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5984 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5985 #endif
5987 return true;
5991 #if ARCH_SIZE==64
5992 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5993 #endif
5994 #if ARCH_SIZE==32
5995 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5996 #endif
5998 /* Fill in the address for a pointer generated in alinker section. */
6000 bfd_vma
6001 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6002 bfd *output_bfd;
6003 bfd *input_bfd;
6004 struct bfd_link_info *info;
6005 elf_linker_section_t *lsect;
6006 struct elf_link_hash_entry *h;
6007 bfd_vma relocation;
6008 const Elf_Internal_Rela *rel;
6009 int relative_reloc;
6011 elf_linker_section_pointers_t *linker_section_ptr;
6013 BFD_ASSERT (lsect != NULL);
6015 if (h != NULL) /* global symbol */
6017 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6018 rel->r_addend,
6019 lsect->which);
6021 BFD_ASSERT (linker_section_ptr != NULL);
6023 if (! elf_hash_table (info)->dynamic_sections_created
6024 || (info->shared
6025 && info->symbolic
6026 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6028 /* This is actually a static link, or it is a
6029 -Bsymbolic link and the symbol is defined
6030 locally. We must initialize this entry in the
6031 global section.
6033 When doing a dynamic link, we create a .rela.<xxx>
6034 relocation entry to initialize the value. This
6035 is done in the finish_dynamic_symbol routine. */
6036 if (!linker_section_ptr->written_address_p)
6038 linker_section_ptr->written_address_p = true;
6039 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6040 lsect->section->contents + linker_section_ptr->offset);
6044 else /* local symbol */
6046 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6047 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6048 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6049 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6050 rel->r_addend,
6051 lsect->which);
6053 BFD_ASSERT (linker_section_ptr != NULL);
6055 /* Write out pointer if it hasn't been rewritten out before */
6056 if (!linker_section_ptr->written_address_p)
6058 linker_section_ptr->written_address_p = true;
6059 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6060 lsect->section->contents + linker_section_ptr->offset);
6062 if (info->shared)
6064 asection *srel = lsect->rel_section;
6065 Elf_Internal_Rela outrel;
6067 /* We need to generate a relative reloc for the dynamic linker. */
6068 if (!srel)
6069 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6070 lsect->rel_name);
6072 BFD_ASSERT (srel != NULL);
6074 outrel.r_offset = (lsect->section->output_section->vma
6075 + lsect->section->output_offset
6076 + linker_section_ptr->offset);
6077 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6078 outrel.r_addend = 0;
6079 elf_swap_reloca_out (output_bfd, &outrel,
6080 (((Elf_External_Rela *)
6081 lsect->section->contents)
6082 + elf_section_data (lsect->section)->rel_count));
6083 ++elf_section_data (lsect->section)->rel_count;
6088 relocation = (lsect->section->output_offset
6089 + linker_section_ptr->offset
6090 - lsect->hole_offset
6091 - lsect->sym_offset);
6093 #ifdef DEBUG
6094 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6095 lsect->name, (long)relocation, (long)relocation);
6096 #endif
6098 /* Subtract out the addend, because it will get added back in by the normal
6099 processing. */
6100 return relocation - linker_section_ptr->addend;
6103 /* Garbage collect unused sections. */
6105 static boolean elf_gc_mark
6106 PARAMS ((struct bfd_link_info *info, asection *sec,
6107 asection * (*gc_mark_hook)
6108 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6109 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6111 static boolean elf_gc_sweep
6112 PARAMS ((struct bfd_link_info *info,
6113 boolean (*gc_sweep_hook)
6114 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6115 const Elf_Internal_Rela *relocs))));
6117 static boolean elf_gc_sweep_symbol
6118 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6120 static boolean elf_gc_allocate_got_offsets
6121 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6123 static boolean elf_gc_propagate_vtable_entries_used
6124 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6126 static boolean elf_gc_smash_unused_vtentry_relocs
6127 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6129 /* The mark phase of garbage collection. For a given section, mark
6130 it, and all the sections which define symbols to which it refers. */
6132 static boolean
6133 elf_gc_mark (info, sec, gc_mark_hook)
6134 struct bfd_link_info *info;
6135 asection *sec;
6136 asection * (*gc_mark_hook)
6137 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6138 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6140 boolean ret = true;
6142 sec->gc_mark = 1;
6144 /* Look through the section relocs. */
6146 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6148 Elf_Internal_Rela *relstart, *rel, *relend;
6149 Elf_Internal_Shdr *symtab_hdr;
6150 struct elf_link_hash_entry **sym_hashes;
6151 size_t nlocsyms;
6152 size_t extsymoff;
6153 Elf_External_Sym *locsyms, *freesyms = NULL;
6154 bfd *input_bfd = sec->owner;
6155 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6157 /* GCFIXME: how to arrange so that relocs and symbols are not
6158 reread continually? */
6160 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6161 sym_hashes = elf_sym_hashes (input_bfd);
6163 /* Read the local symbols. */
6164 if (elf_bad_symtab (input_bfd))
6166 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6167 extsymoff = 0;
6169 else
6170 extsymoff = nlocsyms = symtab_hdr->sh_info;
6171 if (symtab_hdr->contents)
6172 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6173 else if (nlocsyms == 0)
6174 locsyms = NULL;
6175 else
6177 locsyms = freesyms =
6178 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6179 if (freesyms == NULL
6180 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6181 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6182 nlocsyms, input_bfd)
6183 != nlocsyms * sizeof (Elf_External_Sym)))
6185 ret = false;
6186 goto out1;
6190 /* Read the relocations. */
6191 relstart = (NAME(_bfd_elf,link_read_relocs)
6192 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6193 info->keep_memory));
6194 if (relstart == NULL)
6196 ret = false;
6197 goto out1;
6199 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6201 for (rel = relstart; rel < relend; rel++)
6203 unsigned long r_symndx;
6204 asection *rsec;
6205 struct elf_link_hash_entry *h;
6206 Elf_Internal_Sym s;
6208 r_symndx = ELF_R_SYM (rel->r_info);
6209 if (r_symndx == 0)
6210 continue;
6212 if (elf_bad_symtab (sec->owner))
6214 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6215 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6216 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6217 else
6219 h = sym_hashes[r_symndx - extsymoff];
6220 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6223 else if (r_symndx >= nlocsyms)
6225 h = sym_hashes[r_symndx - extsymoff];
6226 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6228 else
6230 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6231 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6234 if (rsec && !rsec->gc_mark)
6235 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6237 ret = false;
6238 goto out2;
6242 out2:
6243 if (!info->keep_memory)
6244 free (relstart);
6245 out1:
6246 if (freesyms)
6247 free (freesyms);
6250 return ret;
6253 /* The sweep phase of garbage collection. Remove all garbage sections. */
6255 static boolean
6256 elf_gc_sweep (info, gc_sweep_hook)
6257 struct bfd_link_info *info;
6258 boolean (*gc_sweep_hook)
6259 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6260 const Elf_Internal_Rela *relocs));
6262 bfd *sub;
6264 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6266 asection *o;
6268 for (o = sub->sections; o != NULL; o = o->next)
6270 /* Keep special sections. Keep .debug sections. */
6271 if ((o->flags & SEC_LINKER_CREATED)
6272 || (o->flags & SEC_DEBUGGING))
6273 o->gc_mark = 1;
6275 if (o->gc_mark)
6276 continue;
6278 /* Skip sweeping sections already excluded. */
6279 if (o->flags & SEC_EXCLUDE)
6280 continue;
6282 /* Since this is early in the link process, it is simple
6283 to remove a section from the output. */
6284 o->flags |= SEC_EXCLUDE;
6286 /* But we also have to update some of the relocation
6287 info we collected before. */
6288 if (gc_sweep_hook
6289 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6291 Elf_Internal_Rela *internal_relocs;
6292 boolean r;
6294 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6295 (o->owner, o, NULL, NULL, info->keep_memory));
6296 if (internal_relocs == NULL)
6297 return false;
6299 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6301 if (!info->keep_memory)
6302 free (internal_relocs);
6304 if (!r)
6305 return false;
6310 /* Remove the symbols that were in the swept sections from the dynamic
6311 symbol table. GCFIXME: Anyone know how to get them out of the
6312 static symbol table as well? */
6314 int i = 0;
6316 elf_link_hash_traverse (elf_hash_table (info),
6317 elf_gc_sweep_symbol,
6318 (PTR) &i);
6320 elf_hash_table (info)->dynsymcount = i;
6323 return true;
6326 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6328 static boolean
6329 elf_gc_sweep_symbol (h, idxptr)
6330 struct elf_link_hash_entry *h;
6331 PTR idxptr;
6333 int *idx = (int *) idxptr;
6335 if (h->dynindx != -1
6336 && ((h->root.type != bfd_link_hash_defined
6337 && h->root.type != bfd_link_hash_defweak)
6338 || h->root.u.def.section->gc_mark))
6339 h->dynindx = (*idx)++;
6341 return true;
6344 /* Propogate collected vtable information. This is called through
6345 elf_link_hash_traverse. */
6347 static boolean
6348 elf_gc_propagate_vtable_entries_used (h, okp)
6349 struct elf_link_hash_entry *h;
6350 PTR okp;
6352 /* Those that are not vtables. */
6353 if (h->vtable_parent == NULL)
6354 return true;
6356 /* Those vtables that do not have parents, we cannot merge. */
6357 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6358 return true;
6360 /* If we've already been done, exit. */
6361 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6362 return true;
6364 /* Make sure the parent's table is up to date. */
6365 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6367 if (h->vtable_entries_used == NULL)
6369 /* None of this table's entries were referenced. Re-use the
6370 parent's table. */
6371 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6372 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6374 else
6376 size_t n;
6377 boolean *cu, *pu;
6379 /* Or the parent's entries into ours. */
6380 cu = h->vtable_entries_used;
6381 cu[-1] = true;
6382 pu = h->vtable_parent->vtable_entries_used;
6383 if (pu != NULL)
6385 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6386 while (--n != 0)
6388 if (*pu) *cu = true;
6389 pu++, cu++;
6394 return true;
6397 static boolean
6398 elf_gc_smash_unused_vtentry_relocs (h, okp)
6399 struct elf_link_hash_entry *h;
6400 PTR okp;
6402 asection *sec;
6403 bfd_vma hstart, hend;
6404 Elf_Internal_Rela *relstart, *relend, *rel;
6405 struct elf_backend_data *bed;
6407 /* Take care of both those symbols that do not describe vtables as
6408 well as those that are not loaded. */
6409 if (h->vtable_parent == NULL)
6410 return true;
6412 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6413 || h->root.type == bfd_link_hash_defweak);
6415 sec = h->root.u.def.section;
6416 hstart = h->root.u.def.value;
6417 hend = hstart + h->size;
6419 relstart = (NAME(_bfd_elf,link_read_relocs)
6420 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6421 if (!relstart)
6422 return *(boolean *)okp = false;
6423 bed = get_elf_backend_data (sec->owner);
6424 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6426 for (rel = relstart; rel < relend; ++rel)
6427 if (rel->r_offset >= hstart && rel->r_offset < hend)
6429 /* If the entry is in use, do nothing. */
6430 if (h->vtable_entries_used
6431 && (rel->r_offset - hstart) < h->vtable_entries_size)
6433 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6434 if (h->vtable_entries_used[entry])
6435 continue;
6437 /* Otherwise, kill it. */
6438 rel->r_offset = rel->r_info = rel->r_addend = 0;
6441 return true;
6444 /* Do mark and sweep of unused sections. */
6446 boolean
6447 elf_gc_sections (abfd, info)
6448 bfd *abfd;
6449 struct bfd_link_info *info;
6451 boolean ok = true;
6452 bfd *sub;
6453 asection * (*gc_mark_hook)
6454 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6455 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6457 if (!get_elf_backend_data (abfd)->can_gc_sections
6458 || info->relocateable
6459 || elf_hash_table (info)->dynamic_sections_created)
6460 return true;
6462 /* Apply transitive closure to the vtable entry usage info. */
6463 elf_link_hash_traverse (elf_hash_table (info),
6464 elf_gc_propagate_vtable_entries_used,
6465 (PTR) &ok);
6466 if (!ok)
6467 return false;
6469 /* Kill the vtable relocations that were not used. */
6470 elf_link_hash_traverse (elf_hash_table (info),
6471 elf_gc_smash_unused_vtentry_relocs,
6472 (PTR) &ok);
6473 if (!ok)
6474 return false;
6476 /* Grovel through relocs to find out who stays ... */
6478 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6479 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6481 asection *o;
6482 for (o = sub->sections; o != NULL; o = o->next)
6484 if (o->flags & SEC_KEEP)
6485 if (!elf_gc_mark (info, o, gc_mark_hook))
6486 return false;
6490 /* ... and mark SEC_EXCLUDE for those that go. */
6491 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6492 return false;
6494 return true;
6497 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6499 boolean
6500 elf_gc_record_vtinherit (abfd, sec, h, offset)
6501 bfd *abfd;
6502 asection *sec;
6503 struct elf_link_hash_entry *h;
6504 bfd_vma offset;
6506 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6507 struct elf_link_hash_entry **search, *child;
6508 bfd_size_type extsymcount;
6510 /* The sh_info field of the symtab header tells us where the
6511 external symbols start. We don't care about the local symbols at
6512 this point. */
6513 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6514 if (!elf_bad_symtab (abfd))
6515 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6517 sym_hashes = elf_sym_hashes (abfd);
6518 sym_hashes_end = sym_hashes + extsymcount;
6520 /* Hunt down the child symbol, which is in this section at the same
6521 offset as the relocation. */
6522 for (search = sym_hashes; search != sym_hashes_end; ++search)
6524 if ((child = *search) != NULL
6525 && (child->root.type == bfd_link_hash_defined
6526 || child->root.type == bfd_link_hash_defweak)
6527 && child->root.u.def.section == sec
6528 && child->root.u.def.value == offset)
6529 goto win;
6532 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6533 bfd_get_filename (abfd), sec->name,
6534 (unsigned long)offset);
6535 bfd_set_error (bfd_error_invalid_operation);
6536 return false;
6538 win:
6539 if (!h)
6541 /* This *should* only be the absolute section. It could potentially
6542 be that someone has defined a non-global vtable though, which
6543 would be bad. It isn't worth paging in the local symbols to be
6544 sure though; that case should simply be handled by the assembler. */
6546 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6548 else
6549 child->vtable_parent = h;
6551 return true;
6554 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6556 boolean
6557 elf_gc_record_vtentry (abfd, sec, h, addend)
6558 bfd *abfd ATTRIBUTE_UNUSED;
6559 asection *sec ATTRIBUTE_UNUSED;
6560 struct elf_link_hash_entry *h;
6561 bfd_vma addend;
6563 if (addend >= h->vtable_entries_size)
6565 size_t size, bytes;
6566 boolean *ptr = h->vtable_entries_used;
6568 /* While the symbol is undefined, we have to be prepared to handle
6569 a zero size. */
6570 if (h->root.type == bfd_link_hash_undefined)
6571 size = addend;
6572 else
6574 size = h->size;
6575 if (size < addend)
6577 /* Oops! We've got a reference past the defined end of
6578 the table. This is probably a bug -- shall we warn? */
6579 size = addend;
6583 /* Allocate one extra entry for use as a "done" flag for the
6584 consolidation pass. */
6585 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6587 if (ptr)
6589 ptr = bfd_realloc (ptr - 1, bytes);
6591 if (ptr != NULL)
6593 size_t oldbytes;
6595 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6596 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6599 else
6600 ptr = bfd_zmalloc (bytes);
6602 if (ptr == NULL)
6603 return false;
6605 /* And arrange for that done flag to be at index -1. */
6606 h->vtable_entries_used = ptr + 1;
6607 h->vtable_entries_size = size;
6610 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6612 return true;
6615 /* And an accompanying bit to work out final got entry offsets once
6616 we're done. Should be called from final_link. */
6618 boolean
6619 elf_gc_common_finalize_got_offsets (abfd, info)
6620 bfd *abfd;
6621 struct bfd_link_info *info;
6623 bfd *i;
6624 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6625 bfd_vma gotoff;
6627 /* The GOT offset is relative to the .got section, but the GOT header is
6628 put into the .got.plt section, if the backend uses it. */
6629 if (bed->want_got_plt)
6630 gotoff = 0;
6631 else
6632 gotoff = bed->got_header_size;
6634 /* Do the local .got entries first. */
6635 for (i = info->input_bfds; i; i = i->link_next)
6637 bfd_signed_vma *local_got = elf_local_got_refcounts (i);
6638 bfd_size_type j, locsymcount;
6639 Elf_Internal_Shdr *symtab_hdr;
6641 if (!local_got)
6642 continue;
6644 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6645 if (elf_bad_symtab (i))
6646 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6647 else
6648 locsymcount = symtab_hdr->sh_info;
6650 for (j = 0; j < locsymcount; ++j)
6652 if (local_got[j] > 0)
6654 local_got[j] = gotoff;
6655 gotoff += ARCH_SIZE / 8;
6657 else
6658 local_got[j] = (bfd_vma) -1;
6662 /* Then the global .got and .plt entries. */
6663 elf_link_hash_traverse (elf_hash_table (info),
6664 elf_gc_allocate_got_offsets,
6665 (PTR) &gotoff);
6666 return true;
6669 /* We need a special top-level link routine to convert got reference counts
6670 to real got offsets. */
6672 static boolean
6673 elf_gc_allocate_got_offsets (h, offarg)
6674 struct elf_link_hash_entry *h;
6675 PTR offarg;
6677 bfd_vma *off = (bfd_vma *) offarg;
6679 if (h->got.refcount > 0)
6681 h->got.offset = off[0];
6682 off[0] += ARCH_SIZE / 8;
6684 else
6685 h->got.offset = (bfd_vma) -1;
6687 return true;
6690 /* Many folk need no more in the way of final link than this, once
6691 got entry reference counting is enabled. */
6693 boolean
6694 elf_gc_common_final_link (abfd, info)
6695 bfd *abfd;
6696 struct bfd_link_info *info;
6698 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6699 return false;
6701 /* Invoke the regular ELF backend linker to do all the work. */
6702 return elf_bfd_final_link (abfd, info);
6705 /* This function will be called though elf_link_hash_traverse to store
6706 all hash value of the exported symbols in an array. */
6708 static boolean
6709 elf_collect_hash_codes (h, data)
6710 struct elf_link_hash_entry *h;
6711 PTR data;
6713 unsigned long **valuep = (unsigned long **) data;
6714 const char *name;
6715 char *p;
6716 unsigned long ha;
6717 char *alc = NULL;
6719 /* Ignore indirect symbols. These are added by the versioning code. */
6720 if (h->dynindx == -1)
6721 return true;
6723 name = h->root.root.string;
6724 p = strchr (name, ELF_VER_CHR);
6725 if (p != NULL)
6727 alc = bfd_malloc (p - name + 1);
6728 memcpy (alc, name, p - name);
6729 alc[p - name] = '\0';
6730 name = alc;
6733 /* Compute the hash value. */
6734 ha = bfd_elf_hash (name);
6736 /* Store the found hash value in the array given as the argument. */
6737 *(*valuep)++ = ha;
6739 /* And store it in the struct so that we can put it in the hash table
6740 later. */
6741 h->elf_hash_value = ha;
6743 if (alc != NULL)
6744 free (alc);
6746 return true;