2000-03-01 H.J. Lu <hjl@gnu.org>
[binutils.git] / bfd / elflink.h
blob394f1c825641f257e40ffcb9e93f3dfb3adc68cc
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20 /* ELF linker code. */
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
25 struct elf_info_failed
27 boolean failed;
28 struct bfd_link_info *info;
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
71 switch (bfd_get_format (abfd))
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
83 /* Return true iff this is a non-common definition of a symbol. */
84 static boolean
85 is_global_symbol_definition (abfd, sym)
86 bfd * abfd;
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;
893 struct elf_backend_data *bed;
895 bed = get_elf_backend_data (abfd);
896 add_symbol_hook = bed->elf_add_symbol_hook;
897 collect = bed->collect;
899 if ((abfd->flags & DYNAMIC) == 0)
900 dynamic = false;
901 else
903 dynamic = true;
905 /* You can't use -r against a dynamic object. Also, there's no
906 hope of using a dynamic object which does not exactly match
907 the format of the output file. */
908 if (info->relocateable || info->hash->creator != abfd->xvec)
910 bfd_set_error (bfd_error_invalid_operation);
911 goto error_return;
915 /* As a GNU extension, any input sections which are named
916 .gnu.warning.SYMBOL are treated as warning symbols for the given
917 symbol. This differs from .gnu.warning sections, which generate
918 warnings when they are included in an output file. */
919 if (! info->shared)
921 asection *s;
923 for (s = abfd->sections; s != NULL; s = s->next)
925 const char *name;
927 name = bfd_get_section_name (abfd, s);
928 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
930 char *msg;
931 bfd_size_type sz;
933 name += sizeof ".gnu.warning." - 1;
935 /* If this is a shared object, then look up the symbol
936 in the hash table. If it is there, and it is already
937 been defined, then we will not be using the entry
938 from this shared object, so we don't need to warn.
939 FIXME: If we see the definition in a regular object
940 later on, we will warn, but we shouldn't. The only
941 fix is to keep track of what warnings we are supposed
942 to emit, and then handle them all at the end of the
943 link. */
944 if (dynamic && abfd->xvec == info->hash->creator)
946 struct elf_link_hash_entry *h;
948 h = elf_link_hash_lookup (elf_hash_table (info), name,
949 false, false, true);
951 /* FIXME: What about bfd_link_hash_common? */
952 if (h != NULL
953 && (h->root.type == bfd_link_hash_defined
954 || h->root.type == bfd_link_hash_defweak))
956 /* We don't want to issue this warning. Clobber
957 the section size so that the warning does not
958 get copied into the output file. */
959 s->_raw_size = 0;
960 continue;
964 sz = bfd_section_size (abfd, s);
965 msg = (char *) bfd_alloc (abfd, sz + 1);
966 if (msg == NULL)
967 goto error_return;
969 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
970 goto error_return;
972 msg[sz] = '\0';
974 if (! (_bfd_generic_link_add_one_symbol
975 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
976 false, collect, (struct bfd_link_hash_entry **) NULL)))
977 goto error_return;
979 if (! info->relocateable)
981 /* Clobber the section size so that the warning does
982 not get copied into the output file. */
983 s->_raw_size = 0;
989 /* If this is a dynamic object, we always link against the .dynsym
990 symbol table, not the .symtab symbol table. The dynamic linker
991 will only see the .dynsym symbol table, so there is no reason to
992 look at .symtab for a dynamic object. */
994 if (! dynamic || elf_dynsymtab (abfd) == 0)
995 hdr = &elf_tdata (abfd)->symtab_hdr;
996 else
997 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
999 if (dynamic)
1001 /* Read in any version definitions. */
1003 if (! _bfd_elf_slurp_version_tables (abfd))
1004 goto error_return;
1006 /* Read in the symbol versions, but don't bother to convert them
1007 to internal format. */
1008 if (elf_dynversym (abfd) != 0)
1010 Elf_Internal_Shdr *versymhdr;
1012 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1013 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1014 if (extversym == NULL)
1015 goto error_return;
1016 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1017 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1018 != versymhdr->sh_size))
1019 goto error_return;
1023 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1025 /* The sh_info field of the symtab header tells us where the
1026 external symbols start. We don't care about the local symbols at
1027 this point. */
1028 if (elf_bad_symtab (abfd))
1030 extsymcount = symcount;
1031 extsymoff = 0;
1033 else
1035 extsymcount = symcount - hdr->sh_info;
1036 extsymoff = hdr->sh_info;
1039 buf = ((Elf_External_Sym *)
1040 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1041 if (buf == NULL && extsymcount != 0)
1042 goto error_return;
1044 /* We store a pointer to the hash table entry for each external
1045 symbol. */
1046 sym_hash = ((struct elf_link_hash_entry **)
1047 bfd_alloc (abfd,
1048 extsymcount * sizeof (struct elf_link_hash_entry *)));
1049 if (sym_hash == NULL)
1050 goto error_return;
1051 elf_sym_hashes (abfd) = sym_hash;
1053 if (! dynamic)
1055 /* If we are creating a shared library, create all the dynamic
1056 sections immediately. We need to attach them to something,
1057 so we attach them to this BFD, provided it is the right
1058 format. FIXME: If there are no input BFD's of the same
1059 format as the output, we can't make a shared library. */
1060 if (info->shared
1061 && ! elf_hash_table (info)->dynamic_sections_created
1062 && abfd->xvec == info->hash->creator)
1064 if (! elf_link_create_dynamic_sections (abfd, info))
1065 goto error_return;
1068 else
1070 asection *s;
1071 boolean add_needed;
1072 const char *name;
1073 bfd_size_type oldsize;
1074 bfd_size_type strindex;
1076 /* Find the name to use in a DT_NEEDED entry that refers to this
1077 object. If the object has a DT_SONAME entry, we use it.
1078 Otherwise, if the generic linker stuck something in
1079 elf_dt_name, we use that. Otherwise, we just use the file
1080 name. If the generic linker put a null string into
1081 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1082 there is a DT_SONAME entry. */
1083 add_needed = true;
1084 name = bfd_get_filename (abfd);
1085 if (elf_dt_name (abfd) != NULL)
1087 name = elf_dt_name (abfd);
1088 if (*name == '\0')
1089 add_needed = false;
1091 s = bfd_get_section_by_name (abfd, ".dynamic");
1092 if (s != NULL)
1094 Elf_External_Dyn *extdyn;
1095 Elf_External_Dyn *extdynend;
1096 int elfsec;
1097 unsigned long link;
1099 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1100 if (dynbuf == NULL)
1101 goto error_return;
1103 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1104 (file_ptr) 0, s->_raw_size))
1105 goto error_return;
1107 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1108 if (elfsec == -1)
1109 goto error_return;
1110 link = elf_elfsections (abfd)[elfsec]->sh_link;
1113 /* The shared libraries distributed with hpux11 have a bogus
1114 sh_link field for the ".dynamic" section. This code detects
1115 when LINK refers to a section that is not a string table and
1116 tries to find the string table for the ".dynsym" section
1117 instead. */
1118 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1119 if (hdr->sh_type != SHT_STRTAB)
1121 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1122 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1123 if (elfsec == -1)
1124 goto error_return;
1125 link = elf_elfsections (abfd)[elfsec]->sh_link;
1129 extdyn = dynbuf;
1130 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1131 for (; extdyn < extdynend; extdyn++)
1133 Elf_Internal_Dyn dyn;
1135 elf_swap_dyn_in (abfd, extdyn, &dyn);
1136 if (dyn.d_tag == DT_SONAME)
1138 name = bfd_elf_string_from_elf_section (abfd, link,
1139 dyn.d_un.d_val);
1140 if (name == NULL)
1141 goto error_return;
1143 if (dyn.d_tag == DT_NEEDED)
1145 struct bfd_link_needed_list *n, **pn;
1146 char *fnm, *anm;
1148 n = ((struct bfd_link_needed_list *)
1149 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1150 fnm = bfd_elf_string_from_elf_section (abfd, link,
1151 dyn.d_un.d_val);
1152 if (n == NULL || fnm == NULL)
1153 goto error_return;
1154 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1155 if (anm == NULL)
1156 goto error_return;
1157 strcpy (anm, fnm);
1158 n->name = anm;
1159 n->by = abfd;
1160 n->next = NULL;
1161 for (pn = &elf_hash_table (info)->needed;
1162 *pn != NULL;
1163 pn = &(*pn)->next)
1165 *pn = n;
1169 free (dynbuf);
1170 dynbuf = NULL;
1173 /* We do not want to include any of the sections in a dynamic
1174 object in the output file. We hack by simply clobbering the
1175 list of sections in the BFD. This could be handled more
1176 cleanly by, say, a new section flag; the existing
1177 SEC_NEVER_LOAD flag is not the one we want, because that one
1178 still implies that the section takes up space in the output
1179 file. */
1180 abfd->sections = NULL;
1181 abfd->section_count = 0;
1183 /* If this is the first dynamic object found in the link, create
1184 the special sections required for dynamic linking. */
1185 if (! elf_hash_table (info)->dynamic_sections_created)
1187 if (! elf_link_create_dynamic_sections (abfd, info))
1188 goto error_return;
1191 if (add_needed)
1193 /* Add a DT_NEEDED entry for this dynamic object. */
1194 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1195 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1196 true, false);
1197 if (strindex == (bfd_size_type) -1)
1198 goto error_return;
1200 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1202 asection *sdyn;
1203 Elf_External_Dyn *dyncon, *dynconend;
1205 /* The hash table size did not change, which means that
1206 the dynamic object name was already entered. If we
1207 have already included this dynamic object in the
1208 link, just ignore it. There is no reason to include
1209 a particular dynamic object more than once. */
1210 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1211 ".dynamic");
1212 BFD_ASSERT (sdyn != NULL);
1214 dyncon = (Elf_External_Dyn *) sdyn->contents;
1215 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1216 sdyn->_raw_size);
1217 for (; dyncon < dynconend; dyncon++)
1219 Elf_Internal_Dyn dyn;
1221 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1222 &dyn);
1223 if (dyn.d_tag == DT_NEEDED
1224 && dyn.d_un.d_val == strindex)
1226 if (buf != NULL)
1227 free (buf);
1228 if (extversym != NULL)
1229 free (extversym);
1230 return true;
1235 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1236 goto error_return;
1239 /* Save the SONAME, if there is one, because sometimes the
1240 linker emulation code will need to know it. */
1241 if (*name == '\0')
1242 name = bfd_get_filename (abfd);
1243 elf_dt_name (abfd) = name;
1246 if (bfd_seek (abfd,
1247 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1248 SEEK_SET) != 0
1249 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1250 != extsymcount * sizeof (Elf_External_Sym)))
1251 goto error_return;
1253 weaks = NULL;
1255 ever = extversym != NULL ? extversym + extsymoff : NULL;
1256 esymend = buf + extsymcount;
1257 for (esym = buf;
1258 esym < esymend;
1259 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1261 Elf_Internal_Sym sym;
1262 int bind;
1263 bfd_vma value;
1264 asection *sec;
1265 flagword flags;
1266 const char *name;
1267 struct elf_link_hash_entry *h;
1268 boolean definition;
1269 boolean size_change_ok, type_change_ok;
1270 boolean new_weakdef;
1271 unsigned int old_alignment;
1273 elf_swap_symbol_in (abfd, esym, &sym);
1275 flags = BSF_NO_FLAGS;
1276 sec = NULL;
1277 value = sym.st_value;
1278 *sym_hash = NULL;
1280 bind = ELF_ST_BIND (sym.st_info);
1281 if (bind == STB_LOCAL)
1283 /* This should be impossible, since ELF requires that all
1284 global symbols follow all local symbols, and that sh_info
1285 point to the first global symbol. Unfortunatealy, Irix 5
1286 screws this up. */
1287 continue;
1289 else if (bind == STB_GLOBAL)
1291 if (sym.st_shndx != SHN_UNDEF
1292 && sym.st_shndx != SHN_COMMON)
1293 flags = BSF_GLOBAL;
1294 else
1295 flags = 0;
1297 else if (bind == STB_WEAK)
1298 flags = BSF_WEAK;
1299 else
1301 /* Leave it up to the processor backend. */
1304 if (sym.st_shndx == SHN_UNDEF)
1305 sec = bfd_und_section_ptr;
1306 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1308 sec = section_from_elf_index (abfd, sym.st_shndx);
1309 if (sec == NULL)
1310 sec = bfd_abs_section_ptr;
1311 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1312 value -= sec->vma;
1314 else if (sym.st_shndx == SHN_ABS)
1315 sec = bfd_abs_section_ptr;
1316 else if (sym.st_shndx == SHN_COMMON)
1318 sec = bfd_com_section_ptr;
1319 /* What ELF calls the size we call the value. What ELF
1320 calls the value we call the alignment. */
1321 value = sym.st_size;
1323 else
1325 /* Leave it up to the processor backend. */
1328 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1329 if (name == (const char *) NULL)
1330 goto error_return;
1332 if (add_symbol_hook)
1334 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1335 &value))
1336 goto error_return;
1338 /* The hook function sets the name to NULL if this symbol
1339 should be skipped for some reason. */
1340 if (name == (const char *) NULL)
1341 continue;
1344 /* Sanity check that all possibilities were handled. */
1345 if (sec == (asection *) NULL)
1347 bfd_set_error (bfd_error_bad_value);
1348 goto error_return;
1351 if (bfd_is_und_section (sec)
1352 || bfd_is_com_section (sec))
1353 definition = false;
1354 else
1355 definition = true;
1357 size_change_ok = false;
1358 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1359 old_alignment = 0;
1360 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1362 Elf_Internal_Versym iver;
1363 unsigned int vernum = 0;
1364 boolean override;
1366 if (ever != NULL)
1368 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1369 vernum = iver.vs_vers & VERSYM_VERSION;
1371 /* If this is a hidden symbol, or if it is not version
1372 1, we append the version name to the symbol name.
1373 However, we do not modify a non-hidden absolute
1374 symbol, because it might be the version symbol
1375 itself. FIXME: What if it isn't? */
1376 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1377 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1379 const char *verstr;
1380 int namelen, newlen;
1381 char *newname, *p;
1383 if (sym.st_shndx != SHN_UNDEF)
1385 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1387 (*_bfd_error_handler)
1388 (_("%s: %s: invalid version %u (max %d)"),
1389 bfd_get_filename (abfd), name, vernum,
1390 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1391 bfd_set_error (bfd_error_bad_value);
1392 goto error_return;
1394 else if (vernum > 1)
1395 verstr =
1396 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1397 else
1398 verstr = "";
1400 else
1402 /* We cannot simply test for the number of
1403 entries in the VERNEED section since the
1404 numbers for the needed versions do not start
1405 at 0. */
1406 Elf_Internal_Verneed *t;
1408 verstr = NULL;
1409 for (t = elf_tdata (abfd)->verref;
1410 t != NULL;
1411 t = t->vn_nextref)
1413 Elf_Internal_Vernaux *a;
1415 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1417 if (a->vna_other == vernum)
1419 verstr = a->vna_nodename;
1420 break;
1423 if (a != NULL)
1424 break;
1426 if (verstr == NULL)
1428 (*_bfd_error_handler)
1429 (_("%s: %s: invalid needed version %d"),
1430 bfd_get_filename (abfd), name, vernum);
1431 bfd_set_error (bfd_error_bad_value);
1432 goto error_return;
1436 namelen = strlen (name);
1437 newlen = namelen + strlen (verstr) + 2;
1438 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1439 ++newlen;
1441 newname = (char *) bfd_alloc (abfd, newlen);
1442 if (newname == NULL)
1443 goto error_return;
1444 strcpy (newname, name);
1445 p = newname + namelen;
1446 *p++ = ELF_VER_CHR;
1447 /* If this is a defined non-hidden version symbol,
1448 we add another @ to the name. This indicates the
1449 default version of the symbol. */
1450 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1451 && sym.st_shndx != SHN_UNDEF)
1452 *p++ = ELF_VER_CHR;
1453 strcpy (p, verstr);
1455 name = newname;
1459 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1460 sym_hash, &override, &type_change_ok,
1461 &size_change_ok))
1462 goto error_return;
1464 if (override)
1465 definition = false;
1467 h = *sym_hash;
1468 while (h->root.type == bfd_link_hash_indirect
1469 || h->root.type == bfd_link_hash_warning)
1470 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1472 /* Remember the old alignment if this is a common symbol, so
1473 that we don't reduce the alignment later on. We can't
1474 check later, because _bfd_generic_link_add_one_symbol
1475 will set a default for the alignment which we want to
1476 override. */
1477 if (h->root.type == bfd_link_hash_common)
1478 old_alignment = h->root.u.c.p->alignment_power;
1480 if (elf_tdata (abfd)->verdef != NULL
1481 && ! override
1482 && vernum > 1
1483 && definition)
1484 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1487 if (! (_bfd_generic_link_add_one_symbol
1488 (info, abfd, name, flags, sec, value, (const char *) NULL,
1489 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1490 goto error_return;
1492 h = *sym_hash;
1493 while (h->root.type == bfd_link_hash_indirect
1494 || h->root.type == bfd_link_hash_warning)
1495 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1496 *sym_hash = h;
1498 new_weakdef = false;
1499 if (dynamic
1500 && definition
1501 && (flags & BSF_WEAK) != 0
1502 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1503 && info->hash->creator->flavour == bfd_target_elf_flavour
1504 && h->weakdef == NULL)
1506 /* Keep a list of all weak defined non function symbols from
1507 a dynamic object, using the weakdef field. Later in this
1508 function we will set the weakdef field to the correct
1509 value. We only put non-function symbols from dynamic
1510 objects on this list, because that happens to be the only
1511 time we need to know the normal symbol corresponding to a
1512 weak symbol, and the information is time consuming to
1513 figure out. If the weakdef field is not already NULL,
1514 then this symbol was already defined by some previous
1515 dynamic object, and we will be using that previous
1516 definition anyhow. */
1518 h->weakdef = weaks;
1519 weaks = h;
1520 new_weakdef = true;
1523 /* Set the alignment of a common symbol. */
1524 if (sym.st_shndx == SHN_COMMON
1525 && h->root.type == bfd_link_hash_common)
1527 unsigned int align;
1529 align = bfd_log2 (sym.st_value);
1530 if (align > old_alignment)
1531 h->root.u.c.p->alignment_power = align;
1534 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1536 int old_flags;
1537 boolean dynsym;
1538 int new_flag;
1540 /* Remember the symbol size and type. */
1541 if (sym.st_size != 0
1542 && (definition || h->size == 0))
1544 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1545 (*_bfd_error_handler)
1546 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1547 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1548 bfd_get_filename (abfd));
1550 h->size = sym.st_size;
1553 /* If this is a common symbol, then we always want H->SIZE
1554 to be the size of the common symbol. The code just above
1555 won't fix the size if a common symbol becomes larger. We
1556 don't warn about a size change here, because that is
1557 covered by --warn-common. */
1558 if (h->root.type == bfd_link_hash_common)
1559 h->size = h->root.u.c.size;
1561 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1562 && (definition || h->type == STT_NOTYPE))
1564 if (h->type != STT_NOTYPE
1565 && h->type != ELF_ST_TYPE (sym.st_info)
1566 && ! type_change_ok)
1567 (*_bfd_error_handler)
1568 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1569 name, h->type, ELF_ST_TYPE (sym.st_info),
1570 bfd_get_filename (abfd));
1572 h->type = ELF_ST_TYPE (sym.st_info);
1575 /* If st_other has a processor-specific meaning, specific code
1576 might be needed here. */
1577 if (sym.st_other != 0)
1579 /* Combine visibilities, using the most constraining one. */
1580 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1581 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1583 if (symvis && (hvis > symvis || hvis == 0))
1584 h->other = sym.st_other;
1586 /* If neither has visibility, use the st_other of the
1587 definition. This is an arbitrary choice, since the
1588 other bits have no general meaning. */
1589 if (!symvis && !hvis
1590 && (definition || h->other == 0))
1591 h->other = sym.st_other;
1594 /* Set a flag in the hash table entry indicating the type of
1595 reference or definition we just found. Keep a count of
1596 the number of dynamic symbols we find. A dynamic symbol
1597 is one which is referenced or defined by both a regular
1598 object and a shared object. */
1599 old_flags = h->elf_link_hash_flags;
1600 dynsym = false;
1601 if (! dynamic)
1603 if (! definition)
1605 new_flag = ELF_LINK_HASH_REF_REGULAR;
1606 if (bind != STB_WEAK)
1607 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1609 else
1610 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1611 if (info->shared
1612 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1613 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1614 dynsym = true;
1616 else
1618 if (! definition)
1619 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1620 else
1621 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1622 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1623 | ELF_LINK_HASH_REF_REGULAR)) != 0
1624 || (h->weakdef != NULL
1625 && ! new_weakdef
1626 && h->weakdef->dynindx != -1))
1627 dynsym = true;
1630 h->elf_link_hash_flags |= new_flag;
1632 /* If this symbol has a version, and it is the default
1633 version, we create an indirect symbol from the default
1634 name to the fully decorated name. This will cause
1635 external references which do not specify a version to be
1636 bound to this version of the symbol. */
1637 if (definition)
1639 char *p;
1641 p = strchr (name, ELF_VER_CHR);
1642 if (p != NULL && p[1] == ELF_VER_CHR)
1644 char *shortname;
1645 struct elf_link_hash_entry *hi;
1646 boolean override;
1648 shortname = bfd_hash_allocate (&info->hash->table,
1649 p - name + 1);
1650 if (shortname == NULL)
1651 goto error_return;
1652 strncpy (shortname, name, p - name);
1653 shortname[p - name] = '\0';
1655 /* We are going to create a new symbol. Merge it
1656 with any existing symbol with this name. For the
1657 purposes of the merge, act as though we were
1658 defining the symbol we just defined, although we
1659 actually going to define an indirect symbol. */
1660 type_change_ok = false;
1661 size_change_ok = false;
1662 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1663 &value, &hi, &override,
1664 &type_change_ok, &size_change_ok))
1665 goto error_return;
1667 if (! override)
1669 if (! (_bfd_generic_link_add_one_symbol
1670 (info, abfd, shortname, BSF_INDIRECT,
1671 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1672 collect, (struct bfd_link_hash_entry **) &hi)))
1673 goto error_return;
1675 else
1677 /* In this case the symbol named SHORTNAME is
1678 overriding the indirect symbol we want to
1679 add. We were planning on making SHORTNAME an
1680 indirect symbol referring to NAME. SHORTNAME
1681 is the name without a version. NAME is the
1682 fully versioned name, and it is the default
1683 version.
1685 Overriding means that we already saw a
1686 definition for the symbol SHORTNAME in a
1687 regular object, and it is overriding the
1688 symbol defined in the dynamic object.
1690 When this happens, we actually want to change
1691 NAME, the symbol we just added, to refer to
1692 SHORTNAME. This will cause references to
1693 NAME in the shared object to become
1694 references to SHORTNAME in the regular
1695 object. This is what we expect when we
1696 override a function in a shared object: that
1697 the references in the shared object will be
1698 mapped to the definition in the regular
1699 object. */
1701 while (hi->root.type == bfd_link_hash_indirect
1702 || hi->root.type == bfd_link_hash_warning)
1703 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1705 h->root.type = bfd_link_hash_indirect;
1706 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1707 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1709 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1710 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1711 if (hi->elf_link_hash_flags
1712 & (ELF_LINK_HASH_REF_REGULAR
1713 | ELF_LINK_HASH_DEF_REGULAR))
1715 if (! _bfd_elf_link_record_dynamic_symbol (info,
1716 hi))
1717 goto error_return;
1721 /* Now set HI to H, so that the following code
1722 will set the other fields correctly. */
1723 hi = h;
1726 /* If there is a duplicate definition somewhere,
1727 then HI may not point to an indirect symbol. We
1728 will have reported an error to the user in that
1729 case. */
1731 if (hi->root.type == bfd_link_hash_indirect)
1733 struct elf_link_hash_entry *ht;
1735 /* If the symbol became indirect, then we assume
1736 that we have not seen a definition before. */
1737 BFD_ASSERT ((hi->elf_link_hash_flags
1738 & (ELF_LINK_HASH_DEF_DYNAMIC
1739 | ELF_LINK_HASH_DEF_REGULAR))
1740 == 0);
1742 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1743 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1745 /* See if the new flags lead us to realize that
1746 the symbol must be dynamic. */
1747 if (! dynsym)
1749 if (! dynamic)
1751 if (info->shared
1752 || ((hi->elf_link_hash_flags
1753 & ELF_LINK_HASH_REF_DYNAMIC)
1754 != 0))
1755 dynsym = true;
1757 else
1759 if ((hi->elf_link_hash_flags
1760 & ELF_LINK_HASH_REF_REGULAR) != 0)
1761 dynsym = true;
1766 /* We also need to define an indirection from the
1767 nondefault version of the symbol. */
1769 shortname = bfd_hash_allocate (&info->hash->table,
1770 strlen (name));
1771 if (shortname == NULL)
1772 goto error_return;
1773 strncpy (shortname, name, p - name);
1774 strcpy (shortname + (p - name), p + 1);
1776 /* Once again, merge with any existing symbol. */
1777 type_change_ok = false;
1778 size_change_ok = false;
1779 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1780 &value, &hi, &override,
1781 &type_change_ok, &size_change_ok))
1782 goto error_return;
1784 if (override)
1786 /* Here SHORTNAME is a versioned name, so we
1787 don't expect to see the type of override we
1788 do in the case above. */
1789 (*_bfd_error_handler)
1790 (_("%s: warning: unexpected redefinition of `%s'"),
1791 bfd_get_filename (abfd), shortname);
1793 else
1795 if (! (_bfd_generic_link_add_one_symbol
1796 (info, abfd, shortname, BSF_INDIRECT,
1797 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1798 collect, (struct bfd_link_hash_entry **) &hi)))
1799 goto error_return;
1801 /* If there is a duplicate definition somewhere,
1802 then HI may not point to an indirect symbol.
1803 We will have reported an error to the user in
1804 that case. */
1806 if (hi->root.type == bfd_link_hash_indirect)
1808 /* If the symbol became indirect, then we
1809 assume that we have not seen a definition
1810 before. */
1811 BFD_ASSERT ((hi->elf_link_hash_flags
1812 & (ELF_LINK_HASH_DEF_DYNAMIC
1813 | ELF_LINK_HASH_DEF_REGULAR))
1814 == 0);
1816 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1818 /* See if the new flags lead us to realize
1819 that the symbol must be dynamic. */
1820 if (! dynsym)
1822 if (! dynamic)
1824 if (info->shared
1825 || ((hi->elf_link_hash_flags
1826 & ELF_LINK_HASH_REF_DYNAMIC)
1827 != 0))
1828 dynsym = true;
1830 else
1832 if ((hi->elf_link_hash_flags
1833 & ELF_LINK_HASH_REF_REGULAR) != 0)
1834 dynsym = true;
1842 if (dynsym && h->dynindx == -1)
1844 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1845 goto error_return;
1846 if (h->weakdef != NULL
1847 && ! new_weakdef
1848 && h->weakdef->dynindx == -1)
1850 if (! _bfd_elf_link_record_dynamic_symbol (info,
1851 h->weakdef))
1852 goto error_return;
1858 /* Now set the weakdefs field correctly for all the weak defined
1859 symbols we found. The only way to do this is to search all the
1860 symbols. Since we only need the information for non functions in
1861 dynamic objects, that's the only time we actually put anything on
1862 the list WEAKS. We need this information so that if a regular
1863 object refers to a symbol defined weakly in a dynamic object, the
1864 real symbol in the dynamic object is also put in the dynamic
1865 symbols; we also must arrange for both symbols to point to the
1866 same memory location. We could handle the general case of symbol
1867 aliasing, but a general symbol alias can only be generated in
1868 assembler code, handling it correctly would be very time
1869 consuming, and other ELF linkers don't handle general aliasing
1870 either. */
1871 while (weaks != NULL)
1873 struct elf_link_hash_entry *hlook;
1874 asection *slook;
1875 bfd_vma vlook;
1876 struct elf_link_hash_entry **hpp;
1877 struct elf_link_hash_entry **hppend;
1879 hlook = weaks;
1880 weaks = hlook->weakdef;
1881 hlook->weakdef = NULL;
1883 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1884 || hlook->root.type == bfd_link_hash_defweak
1885 || hlook->root.type == bfd_link_hash_common
1886 || hlook->root.type == bfd_link_hash_indirect);
1887 slook = hlook->root.u.def.section;
1888 vlook = hlook->root.u.def.value;
1890 hpp = elf_sym_hashes (abfd);
1891 hppend = hpp + extsymcount;
1892 for (; hpp < hppend; hpp++)
1894 struct elf_link_hash_entry *h;
1896 h = *hpp;
1897 if (h != NULL && h != hlook
1898 && h->root.type == bfd_link_hash_defined
1899 && h->root.u.def.section == slook
1900 && h->root.u.def.value == vlook)
1902 hlook->weakdef = h;
1904 /* If the weak definition is in the list of dynamic
1905 symbols, make sure the real definition is put there
1906 as well. */
1907 if (hlook->dynindx != -1
1908 && h->dynindx == -1)
1910 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1911 goto error_return;
1914 /* If the real definition is in the list of dynamic
1915 symbols, make sure the weak definition is put there
1916 as well. If we don't do this, then the dynamic
1917 loader might not merge the entries for the real
1918 definition and the weak definition. */
1919 if (h->dynindx != -1
1920 && hlook->dynindx == -1)
1922 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1923 goto error_return;
1926 break;
1931 if (buf != NULL)
1933 free (buf);
1934 buf = NULL;
1937 if (extversym != NULL)
1939 free (extversym);
1940 extversym = NULL;
1943 /* If this object is the same format as the output object, and it is
1944 not a shared library, then let the backend look through the
1945 relocs.
1947 This is required to build global offset table entries and to
1948 arrange for dynamic relocs. It is not required for the
1949 particular common case of linking non PIC code, even when linking
1950 against shared libraries, but unfortunately there is no way of
1951 knowing whether an object file has been compiled PIC or not.
1952 Looking through the relocs is not particularly time consuming.
1953 The problem is that we must either (1) keep the relocs in memory,
1954 which causes the linker to require additional runtime memory or
1955 (2) read the relocs twice from the input file, which wastes time.
1956 This would be a good case for using mmap.
1958 I have no idea how to handle linking PIC code into a file of a
1959 different format. It probably can't be done. */
1960 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1961 if (! dynamic
1962 && abfd->xvec == info->hash->creator
1963 && check_relocs != NULL)
1965 asection *o;
1967 for (o = abfd->sections; o != NULL; o = o->next)
1969 Elf_Internal_Rela *internal_relocs;
1970 boolean ok;
1972 if ((o->flags & SEC_RELOC) == 0
1973 || o->reloc_count == 0
1974 || ((info->strip == strip_all || info->strip == strip_debugger)
1975 && (o->flags & SEC_DEBUGGING) != 0)
1976 || bfd_is_abs_section (o->output_section))
1977 continue;
1979 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1980 (abfd, o, (PTR) NULL,
1981 (Elf_Internal_Rela *) NULL,
1982 info->keep_memory));
1983 if (internal_relocs == NULL)
1984 goto error_return;
1986 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1988 if (! info->keep_memory)
1989 free (internal_relocs);
1991 if (! ok)
1992 goto error_return;
1996 /* If this is a non-traditional, non-relocateable link, try to
1997 optimize the handling of the .stab/.stabstr sections. */
1998 if (! dynamic
1999 && ! info->relocateable
2000 && ! info->traditional_format
2001 && info->hash->creator->flavour == bfd_target_elf_flavour
2002 && (info->strip != strip_all && info->strip != strip_debugger))
2004 asection *stab, *stabstr;
2006 stab = bfd_get_section_by_name (abfd, ".stab");
2007 if (stab != NULL)
2009 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2011 if (stabstr != NULL)
2013 struct bfd_elf_section_data *secdata;
2015 secdata = elf_section_data (stab);
2016 if (! _bfd_link_section_stabs (abfd,
2017 &elf_hash_table (info)->stab_info,
2018 stab, stabstr,
2019 &secdata->stab_info))
2020 goto error_return;
2025 return true;
2027 error_return:
2028 if (buf != NULL)
2029 free (buf);
2030 if (dynbuf != NULL)
2031 free (dynbuf);
2032 if (dynver != NULL)
2033 free (dynver);
2034 if (extversym != NULL)
2035 free (extversym);
2036 return false;
2039 /* Create some sections which will be filled in with dynamic linking
2040 information. ABFD is an input file which requires dynamic sections
2041 to be created. The dynamic sections take up virtual memory space
2042 when the final executable is run, so we need to create them before
2043 addresses are assigned to the output sections. We work out the
2044 actual contents and size of these sections later. */
2046 boolean
2047 elf_link_create_dynamic_sections (abfd, info)
2048 bfd *abfd;
2049 struct bfd_link_info *info;
2051 flagword flags;
2052 register asection *s;
2053 struct elf_link_hash_entry *h;
2054 struct elf_backend_data *bed;
2056 if (elf_hash_table (info)->dynamic_sections_created)
2057 return true;
2059 /* Make sure that all dynamic sections use the same input BFD. */
2060 if (elf_hash_table (info)->dynobj == NULL)
2061 elf_hash_table (info)->dynobj = abfd;
2062 else
2063 abfd = elf_hash_table (info)->dynobj;
2065 /* Note that we set the SEC_IN_MEMORY flag for all of these
2066 sections. */
2067 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2068 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2070 /* A dynamically linked executable has a .interp section, but a
2071 shared library does not. */
2072 if (! info->shared)
2074 s = bfd_make_section (abfd, ".interp");
2075 if (s == NULL
2076 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2077 return false;
2080 /* Create sections to hold version informations. These are removed
2081 if they are not needed. */
2082 s = bfd_make_section (abfd, ".gnu.version_d");
2083 if (s == NULL
2084 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2085 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2086 return false;
2088 s = bfd_make_section (abfd, ".gnu.version");
2089 if (s == NULL
2090 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2091 || ! bfd_set_section_alignment (abfd, s, 1))
2092 return false;
2094 s = bfd_make_section (abfd, ".gnu.version_r");
2095 if (s == NULL
2096 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2097 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2098 return false;
2100 s = bfd_make_section (abfd, ".dynsym");
2101 if (s == NULL
2102 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2103 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2104 return false;
2106 s = bfd_make_section (abfd, ".dynstr");
2107 if (s == NULL
2108 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2109 return false;
2111 /* Create a strtab to hold the dynamic symbol names. */
2112 if (elf_hash_table (info)->dynstr == NULL)
2114 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2115 if (elf_hash_table (info)->dynstr == NULL)
2116 return false;
2119 s = bfd_make_section (abfd, ".dynamic");
2120 if (s == NULL
2121 || ! bfd_set_section_flags (abfd, s, flags)
2122 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2123 return false;
2125 /* The special symbol _DYNAMIC is always set to the start of the
2126 .dynamic section. This call occurs before we have processed the
2127 symbols for any dynamic object, so we don't have to worry about
2128 overriding a dynamic definition. We could set _DYNAMIC in a
2129 linker script, but we only want to define it if we are, in fact,
2130 creating a .dynamic section. We don't want to define it if there
2131 is no .dynamic section, since on some ELF platforms the start up
2132 code examines it to decide how to initialize the process. */
2133 h = NULL;
2134 if (! (_bfd_generic_link_add_one_symbol
2135 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2136 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2137 (struct bfd_link_hash_entry **) &h)))
2138 return false;
2139 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2140 h->type = STT_OBJECT;
2142 if (info->shared
2143 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2144 return false;
2146 bed = get_elf_backend_data (abfd);
2148 s = bfd_make_section (abfd, ".hash");
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;
2153 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2155 /* Let the backend create the rest of the sections. This lets the
2156 backend set the right flags. The backend will normally create
2157 the .got and .plt sections. */
2158 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2159 return false;
2161 elf_hash_table (info)->dynamic_sections_created = true;
2163 return true;
2166 /* Add an entry to the .dynamic table. */
2168 boolean
2169 elf_add_dynamic_entry (info, tag, val)
2170 struct bfd_link_info *info;
2171 bfd_vma tag;
2172 bfd_vma val;
2174 Elf_Internal_Dyn dyn;
2175 bfd *dynobj;
2176 asection *s;
2177 size_t newsize;
2178 bfd_byte *newcontents;
2180 dynobj = elf_hash_table (info)->dynobj;
2182 s = bfd_get_section_by_name (dynobj, ".dynamic");
2183 BFD_ASSERT (s != NULL);
2185 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2186 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2187 if (newcontents == NULL)
2188 return false;
2190 dyn.d_tag = tag;
2191 dyn.d_un.d_val = val;
2192 elf_swap_dyn_out (dynobj, &dyn,
2193 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2195 s->_raw_size = newsize;
2196 s->contents = newcontents;
2198 return true;
2201 /* Record a new local dynamic symbol. */
2203 boolean
2204 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2205 struct bfd_link_info *info;
2206 bfd *input_bfd;
2207 long input_indx;
2209 struct elf_link_local_dynamic_entry *entry;
2210 struct elf_link_hash_table *eht;
2211 struct bfd_strtab_hash *dynstr;
2212 Elf_External_Sym esym;
2213 unsigned long dynstr_index;
2214 char *name;
2216 /* See if the entry exists already. */
2217 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2218 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2219 return true;
2221 entry = (struct elf_link_local_dynamic_entry *)
2222 bfd_alloc (input_bfd, sizeof (*entry));
2223 if (entry == NULL)
2224 return false;
2226 /* Go find the symbol, so that we can find it's name. */
2227 if (bfd_seek (input_bfd,
2228 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2229 + input_indx * sizeof (Elf_External_Sym)),
2230 SEEK_SET) != 0
2231 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2232 != sizeof (Elf_External_Sym)))
2233 return false;
2234 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2236 name = (bfd_elf_string_from_elf_section
2237 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2238 entry->isym.st_name));
2240 dynstr = elf_hash_table (info)->dynstr;
2241 if (dynstr == NULL)
2243 /* Create a strtab to hold the dynamic symbol names. */
2244 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2245 if (dynstr == NULL)
2246 return false;
2249 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2250 if (dynstr_index == (unsigned long) -1)
2251 return false;
2252 entry->isym.st_name = dynstr_index;
2254 eht = elf_hash_table (info);
2256 entry->next = eht->dynlocal;
2257 eht->dynlocal = entry;
2258 entry->input_bfd = input_bfd;
2259 entry->input_indx = input_indx;
2260 eht->dynsymcount++;
2262 /* Whatever binding the symbol had before, it's now local. */
2263 entry->isym.st_info
2264 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2266 /* The dynindx will be set at the end of size_dynamic_sections. */
2268 return true;
2272 /* Read and swap the relocs from the section indicated by SHDR. This
2273 may be either a REL or a RELA section. The relocations are
2274 translated into RELA relocations and stored in INTERNAL_RELOCS,
2275 which should have already been allocated to contain enough space.
2276 The EXTERNAL_RELOCS are a buffer where the external form of the
2277 relocations should be stored.
2279 Returns false if something goes wrong. */
2281 static boolean
2282 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2283 internal_relocs)
2284 bfd *abfd;
2285 Elf_Internal_Shdr *shdr;
2286 PTR external_relocs;
2287 Elf_Internal_Rela *internal_relocs;
2289 struct elf_backend_data *bed;
2291 /* If there aren't any relocations, that's OK. */
2292 if (!shdr)
2293 return true;
2295 /* Position ourselves at the start of the section. */
2296 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2297 return false;
2299 /* Read the relocations. */
2300 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2301 != shdr->sh_size)
2302 return false;
2304 bed = get_elf_backend_data (abfd);
2306 /* Convert the external relocations to the internal format. */
2307 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2309 Elf_External_Rel *erel;
2310 Elf_External_Rel *erelend;
2311 Elf_Internal_Rela *irela;
2312 Elf_Internal_Rel *irel;
2314 erel = (Elf_External_Rel *) external_relocs;
2315 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2316 irela = internal_relocs;
2317 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2318 * sizeof (Elf_Internal_Rel)));
2319 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2321 unsigned char i;
2323 if (bed->s->swap_reloc_in)
2324 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2325 else
2326 elf_swap_reloc_in (abfd, erel, irel);
2328 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2330 irela[i].r_offset = irel[i].r_offset;
2331 irela[i].r_info = irel[i].r_info;
2332 irela[i].r_addend = 0;
2336 else
2338 Elf_External_Rela *erela;
2339 Elf_External_Rela *erelaend;
2340 Elf_Internal_Rela *irela;
2342 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2344 erela = (Elf_External_Rela *) external_relocs;
2345 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2346 irela = internal_relocs;
2347 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2349 if (bed->s->swap_reloca_in)
2350 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2351 else
2352 elf_swap_reloca_in (abfd, erela, irela);
2356 return true;
2359 /* Read and swap the relocs for a section O. They may have been
2360 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2361 not NULL, they are used as buffers to read into. They are known to
2362 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2363 the return value is allocated using either malloc or bfd_alloc,
2364 according to the KEEP_MEMORY argument. If O has two relocation
2365 sections (both REL and RELA relocations), then the REL_HDR
2366 relocations will appear first in INTERNAL_RELOCS, followed by the
2367 REL_HDR2 relocations. */
2369 Elf_Internal_Rela *
2370 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2371 keep_memory)
2372 bfd *abfd;
2373 asection *o;
2374 PTR external_relocs;
2375 Elf_Internal_Rela *internal_relocs;
2376 boolean keep_memory;
2378 Elf_Internal_Shdr *rel_hdr;
2379 PTR alloc1 = NULL;
2380 Elf_Internal_Rela *alloc2 = NULL;
2381 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2383 if (elf_section_data (o)->relocs != NULL)
2384 return elf_section_data (o)->relocs;
2386 if (o->reloc_count == 0)
2387 return NULL;
2389 rel_hdr = &elf_section_data (o)->rel_hdr;
2391 if (internal_relocs == NULL)
2393 size_t size;
2395 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2396 * sizeof (Elf_Internal_Rela));
2397 if (keep_memory)
2398 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2399 else
2400 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2401 if (internal_relocs == NULL)
2402 goto error_return;
2405 if (external_relocs == NULL)
2407 size_t size = (size_t) rel_hdr->sh_size;
2409 if (elf_section_data (o)->rel_hdr2)
2410 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2411 alloc1 = (PTR) bfd_malloc (size);
2412 if (alloc1 == NULL)
2413 goto error_return;
2414 external_relocs = alloc1;
2417 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2418 external_relocs,
2419 internal_relocs))
2420 goto error_return;
2421 if (!elf_link_read_relocs_from_section
2422 (abfd,
2423 elf_section_data (o)->rel_hdr2,
2424 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2425 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2426 * bed->s->int_rels_per_ext_rel)))
2427 goto error_return;
2429 /* Cache the results for next time, if we can. */
2430 if (keep_memory)
2431 elf_section_data (o)->relocs = internal_relocs;
2433 if (alloc1 != NULL)
2434 free (alloc1);
2436 /* Don't free alloc2, since if it was allocated we are passing it
2437 back (under the name of internal_relocs). */
2439 return internal_relocs;
2441 error_return:
2442 if (alloc1 != NULL)
2443 free (alloc1);
2444 if (alloc2 != NULL)
2445 free (alloc2);
2446 return NULL;
2450 /* Record an assignment to a symbol made by a linker script. We need
2451 this in case some dynamic object refers to this symbol. */
2453 /*ARGSUSED*/
2454 boolean
2455 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2456 bfd *output_bfd ATTRIBUTE_UNUSED;
2457 struct bfd_link_info *info;
2458 const char *name;
2459 boolean provide;
2461 struct elf_link_hash_entry *h;
2463 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2464 return true;
2466 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2467 if (h == NULL)
2468 return false;
2470 if (h->root.type == bfd_link_hash_new)
2471 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2473 /* If this symbol is being provided by the linker script, and it is
2474 currently defined by a dynamic object, but not by a regular
2475 object, then mark it as undefined so that the generic linker will
2476 force the correct value. */
2477 if (provide
2478 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2479 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2480 h->root.type = bfd_link_hash_undefined;
2482 /* If this symbol is not being provided by the linker script, and it is
2483 currently defined by a dynamic object, but not by a regular object,
2484 then clear out any version information because the symbol will not be
2485 associated with the dynamic object any more. */
2486 if (!provide
2487 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2488 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2489 h->verinfo.verdef = NULL;
2491 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2493 /* When possible, keep the original type of the symbol */
2494 if (h->type == STT_NOTYPE)
2495 h->type = STT_OBJECT;
2497 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2498 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2499 || info->shared)
2500 && h->dynindx == -1)
2502 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2503 return false;
2505 /* If this is a weak defined symbol, and we know a corresponding
2506 real symbol from the same dynamic object, make sure the real
2507 symbol is also made into a dynamic symbol. */
2508 if (h->weakdef != NULL
2509 && h->weakdef->dynindx == -1)
2511 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2512 return false;
2516 return true;
2519 /* This structure is used to pass information to
2520 elf_link_assign_sym_version. */
2522 struct elf_assign_sym_version_info
2524 /* Output BFD. */
2525 bfd *output_bfd;
2526 /* General link information. */
2527 struct bfd_link_info *info;
2528 /* Version tree. */
2529 struct bfd_elf_version_tree *verdefs;
2530 /* Whether we are exporting all dynamic symbols. */
2531 boolean export_dynamic;
2532 /* Whether we had a failure. */
2533 boolean failed;
2536 /* This structure is used to pass information to
2537 elf_link_find_version_dependencies. */
2539 struct elf_find_verdep_info
2541 /* Output BFD. */
2542 bfd *output_bfd;
2543 /* General link information. */
2544 struct bfd_link_info *info;
2545 /* The number of dependencies. */
2546 unsigned int vers;
2547 /* Whether we had a failure. */
2548 boolean failed;
2551 /* Array used to determine the number of hash table buckets to use
2552 based on the number of symbols there are. If there are fewer than
2553 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2554 fewer than 37 we use 17 buckets, and so forth. We never use more
2555 than 32771 buckets. */
2557 static const size_t elf_buckets[] =
2559 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2560 16411, 32771, 0
2563 /* Compute bucket count for hashing table. We do not use a static set
2564 of possible tables sizes anymore. Instead we determine for all
2565 possible reasonable sizes of the table the outcome (i.e., the
2566 number of collisions etc) and choose the best solution. The
2567 weighting functions are not too simple to allow the table to grow
2568 without bounds. Instead one of the weighting factors is the size.
2569 Therefore the result is always a good payoff between few collisions
2570 (= short chain lengths) and table size. */
2571 static size_t
2572 compute_bucket_count (info)
2573 struct bfd_link_info *info;
2575 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2576 size_t best_size = 0;
2577 unsigned long int *hashcodes;
2578 unsigned long int *hashcodesp;
2579 unsigned long int i;
2581 /* Compute the hash values for all exported symbols. At the same
2582 time store the values in an array so that we could use them for
2583 optimizations. */
2584 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2585 * sizeof (unsigned long int));
2586 if (hashcodes == NULL)
2587 return 0;
2588 hashcodesp = hashcodes;
2590 /* Put all hash values in HASHCODES. */
2591 elf_link_hash_traverse (elf_hash_table (info),
2592 elf_collect_hash_codes, &hashcodesp);
2594 /* We have a problem here. The following code to optimize the table
2595 size requires an integer type with more the 32 bits. If
2596 BFD_HOST_U_64_BIT is set we know about such a type. */
2597 #ifdef BFD_HOST_U_64_BIT
2598 if (info->optimize == true)
2600 unsigned long int nsyms = hashcodesp - hashcodes;
2601 size_t minsize;
2602 size_t maxsize;
2603 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2604 unsigned long int *counts ;
2606 /* Possible optimization parameters: if we have NSYMS symbols we say
2607 that the hashing table must at least have NSYMS/4 and at most
2608 2*NSYMS buckets. */
2609 minsize = nsyms / 4;
2610 if (minsize == 0)
2611 minsize = 1;
2612 best_size = maxsize = nsyms * 2;
2614 /* Create array where we count the collisions in. We must use bfd_malloc
2615 since the size could be large. */
2616 counts = (unsigned long int *) bfd_malloc (maxsize
2617 * sizeof (unsigned long int));
2618 if (counts == NULL)
2620 free (hashcodes);
2621 return 0;
2624 /* Compute the "optimal" size for the hash table. The criteria is a
2625 minimal chain length. The minor criteria is (of course) the size
2626 of the table. */
2627 for (i = minsize; i < maxsize; ++i)
2629 /* Walk through the array of hashcodes and count the collisions. */
2630 BFD_HOST_U_64_BIT max;
2631 unsigned long int j;
2632 unsigned long int fact;
2634 memset (counts, '\0', i * sizeof (unsigned long int));
2636 /* Determine how often each hash bucket is used. */
2637 for (j = 0; j < nsyms; ++j)
2638 ++counts[hashcodes[j] % i];
2640 /* For the weight function we need some information about the
2641 pagesize on the target. This is information need not be 100%
2642 accurate. Since this information is not available (so far) we
2643 define it here to a reasonable default value. If it is crucial
2644 to have a better value some day simply define this value. */
2645 # ifndef BFD_TARGET_PAGESIZE
2646 # define BFD_TARGET_PAGESIZE (4096)
2647 # endif
2649 /* We in any case need 2 + NSYMS entries for the size values and
2650 the chains. */
2651 max = (2 + nsyms) * (ARCH_SIZE / 8);
2653 # if 1
2654 /* Variant 1: optimize for short chains. We add the squares
2655 of all the chain lengths (which favous many small chain
2656 over a few long chains). */
2657 for (j = 0; j < i; ++j)
2658 max += counts[j] * counts[j];
2660 /* This adds penalties for the overall size of the table. */
2661 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2662 max *= fact * fact;
2663 # else
2664 /* Variant 2: Optimize a lot more for small table. Here we
2665 also add squares of the size but we also add penalties for
2666 empty slots (the +1 term). */
2667 for (j = 0; j < i; ++j)
2668 max += (1 + counts[j]) * (1 + counts[j]);
2670 /* The overall size of the table is considered, but not as
2671 strong as in variant 1, where it is squared. */
2672 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2673 max *= fact;
2674 # endif
2676 /* Compare with current best results. */
2677 if (max < best_chlen)
2679 best_chlen = max;
2680 best_size = i;
2684 free (counts);
2686 else
2687 #endif /* defined (BFD_HOST_U_64_BIT) */
2689 /* This is the fallback solution if no 64bit type is available or if we
2690 are not supposed to spend much time on optimizations. We select the
2691 bucket count using a fixed set of numbers. */
2692 for (i = 0; elf_buckets[i] != 0; i++)
2694 best_size = elf_buckets[i];
2695 if (dynsymcount < elf_buckets[i + 1])
2696 break;
2700 /* Free the arrays we needed. */
2701 free (hashcodes);
2703 return best_size;
2706 /* Set up the sizes and contents of the ELF dynamic sections. This is
2707 called by the ELF linker emulation before_allocation routine. We
2708 must set the sizes of the sections before the linker sets the
2709 addresses of the various sections. */
2711 boolean
2712 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2713 export_dynamic, filter_shlib,
2714 auxiliary_filters, info, sinterpptr,
2715 verdefs)
2716 bfd *output_bfd;
2717 const char *soname;
2718 const char *rpath;
2719 boolean export_dynamic;
2720 const char *filter_shlib;
2721 const char * const *auxiliary_filters;
2722 struct bfd_link_info *info;
2723 asection **sinterpptr;
2724 struct bfd_elf_version_tree *verdefs;
2726 bfd_size_type soname_indx;
2727 bfd *dynobj;
2728 struct elf_backend_data *bed;
2729 struct elf_assign_sym_version_info asvinfo;
2731 *sinterpptr = NULL;
2733 soname_indx = (bfd_size_type) -1;
2735 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2736 return true;
2738 /* The backend may have to create some sections regardless of whether
2739 we're dynamic or not. */
2740 bed = get_elf_backend_data (output_bfd);
2741 if (bed->elf_backend_always_size_sections
2742 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2743 return false;
2745 dynobj = elf_hash_table (info)->dynobj;
2747 /* If there were no dynamic objects in the link, there is nothing to
2748 do here. */
2749 if (dynobj == NULL)
2750 return true;
2752 if (elf_hash_table (info)->dynamic_sections_created)
2754 struct elf_info_failed eif;
2755 struct elf_link_hash_entry *h;
2756 bfd_size_type strsize;
2758 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2759 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2761 if (soname != NULL)
2763 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2764 soname, true, true);
2765 if (soname_indx == (bfd_size_type) -1
2766 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2767 return false;
2770 if (info->symbolic)
2772 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2773 return false;
2776 if (rpath != NULL)
2778 bfd_size_type indx;
2780 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2781 true, true);
2782 if (indx == (bfd_size_type) -1
2783 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2784 return false;
2787 if (filter_shlib != NULL)
2789 bfd_size_type indx;
2791 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2792 filter_shlib, true, true);
2793 if (indx == (bfd_size_type) -1
2794 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2795 return false;
2798 if (auxiliary_filters != NULL)
2800 const char * const *p;
2802 for (p = auxiliary_filters; *p != NULL; p++)
2804 bfd_size_type indx;
2806 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2807 *p, true, true);
2808 if (indx == (bfd_size_type) -1
2809 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2810 return false;
2814 /* If we are supposed to export all symbols into the dynamic symbol
2815 table (this is not the normal case), then do so. */
2816 if (export_dynamic)
2818 struct elf_info_failed eif;
2820 eif.failed = false;
2821 eif.info = info;
2822 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2823 (PTR) &eif);
2824 if (eif.failed)
2825 return false;
2828 /* Attach all the symbols to their version information. */
2829 asvinfo.output_bfd = output_bfd;
2830 asvinfo.info = info;
2831 asvinfo.verdefs = verdefs;
2832 asvinfo.export_dynamic = export_dynamic;
2833 asvinfo.failed = false;
2835 elf_link_hash_traverse (elf_hash_table (info),
2836 elf_link_assign_sym_version,
2837 (PTR) &asvinfo);
2838 if (asvinfo.failed)
2839 return false;
2841 /* Find all symbols which were defined in a dynamic object and make
2842 the backend pick a reasonable value for them. */
2843 eif.failed = false;
2844 eif.info = info;
2845 elf_link_hash_traverse (elf_hash_table (info),
2846 elf_adjust_dynamic_symbol,
2847 (PTR) &eif);
2848 if (eif.failed)
2849 return false;
2851 /* Add some entries to the .dynamic section. We fill in some of the
2852 values later, in elf_bfd_final_link, but we must add the entries
2853 now so that we know the final size of the .dynamic section. */
2855 /* If there are initialization and/or finalization functions to
2856 call then add the corresponding DT_INIT/DT_FINI entries. */
2857 h = (info->init_function
2858 ? elf_link_hash_lookup (elf_hash_table (info),
2859 info->init_function, false,
2860 false, false)
2861 : NULL);
2862 if (h != NULL
2863 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2864 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2866 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2867 return false;
2869 h = (info->fini_function
2870 ? elf_link_hash_lookup (elf_hash_table (info),
2871 info->fini_function, false,
2872 false, false)
2873 : NULL);
2874 if (h != NULL
2875 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2876 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2878 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2879 return false;
2882 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2883 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2884 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2885 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2886 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2887 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2888 sizeof (Elf_External_Sym)))
2889 return false;
2892 /* The backend must work out the sizes of all the other dynamic
2893 sections. */
2894 if (bed->elf_backend_size_dynamic_sections
2895 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2896 return false;
2898 if (elf_hash_table (info)->dynamic_sections_created)
2900 size_t dynsymcount;
2901 asection *s;
2902 size_t bucketcount = 0;
2903 Elf_Internal_Sym isym;
2904 size_t hash_entry_size;
2906 /* Set up the version definition section. */
2907 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2908 BFD_ASSERT (s != NULL);
2910 /* We may have created additional version definitions if we are
2911 just linking a regular application. */
2912 verdefs = asvinfo.verdefs;
2914 if (verdefs == NULL)
2915 _bfd_strip_section_from_output (info, s);
2916 else
2918 unsigned int cdefs;
2919 bfd_size_type size;
2920 struct bfd_elf_version_tree *t;
2921 bfd_byte *p;
2922 Elf_Internal_Verdef def;
2923 Elf_Internal_Verdaux defaux;
2925 cdefs = 0;
2926 size = 0;
2928 /* Make space for the base version. */
2929 size += sizeof (Elf_External_Verdef);
2930 size += sizeof (Elf_External_Verdaux);
2931 ++cdefs;
2933 for (t = verdefs; t != NULL; t = t->next)
2935 struct bfd_elf_version_deps *n;
2937 size += sizeof (Elf_External_Verdef);
2938 size += sizeof (Elf_External_Verdaux);
2939 ++cdefs;
2941 for (n = t->deps; n != NULL; n = n->next)
2942 size += sizeof (Elf_External_Verdaux);
2945 s->_raw_size = size;
2946 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2947 if (s->contents == NULL && s->_raw_size != 0)
2948 return false;
2950 /* Fill in the version definition section. */
2952 p = s->contents;
2954 def.vd_version = VER_DEF_CURRENT;
2955 def.vd_flags = VER_FLG_BASE;
2956 def.vd_ndx = 1;
2957 def.vd_cnt = 1;
2958 def.vd_aux = sizeof (Elf_External_Verdef);
2959 def.vd_next = (sizeof (Elf_External_Verdef)
2960 + sizeof (Elf_External_Verdaux));
2962 if (soname_indx != (bfd_size_type) -1)
2964 def.vd_hash = bfd_elf_hash (soname);
2965 defaux.vda_name = soname_indx;
2967 else
2969 const char *name;
2970 bfd_size_type indx;
2972 name = output_bfd->filename;
2973 def.vd_hash = bfd_elf_hash (name);
2974 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2975 name, true, false);
2976 if (indx == (bfd_size_type) -1)
2977 return false;
2978 defaux.vda_name = indx;
2980 defaux.vda_next = 0;
2982 _bfd_elf_swap_verdef_out (output_bfd, &def,
2983 (Elf_External_Verdef *)p);
2984 p += sizeof (Elf_External_Verdef);
2985 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2986 (Elf_External_Verdaux *) p);
2987 p += sizeof (Elf_External_Verdaux);
2989 for (t = verdefs; t != NULL; t = t->next)
2991 unsigned int cdeps;
2992 struct bfd_elf_version_deps *n;
2993 struct elf_link_hash_entry *h;
2995 cdeps = 0;
2996 for (n = t->deps; n != NULL; n = n->next)
2997 ++cdeps;
2999 /* Add a symbol representing this version. */
3000 h = NULL;
3001 if (! (_bfd_generic_link_add_one_symbol
3002 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3003 (bfd_vma) 0, (const char *) NULL, false,
3004 get_elf_backend_data (dynobj)->collect,
3005 (struct bfd_link_hash_entry **) &h)))
3006 return false;
3007 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3008 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3009 h->type = STT_OBJECT;
3010 h->verinfo.vertree = t;
3012 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3013 return false;
3015 def.vd_version = VER_DEF_CURRENT;
3016 def.vd_flags = 0;
3017 if (t->globals == NULL && t->locals == NULL && ! t->used)
3018 def.vd_flags |= VER_FLG_WEAK;
3019 def.vd_ndx = t->vernum + 1;
3020 def.vd_cnt = cdeps + 1;
3021 def.vd_hash = bfd_elf_hash (t->name);
3022 def.vd_aux = sizeof (Elf_External_Verdef);
3023 if (t->next != NULL)
3024 def.vd_next = (sizeof (Elf_External_Verdef)
3025 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3026 else
3027 def.vd_next = 0;
3029 _bfd_elf_swap_verdef_out (output_bfd, &def,
3030 (Elf_External_Verdef *) p);
3031 p += sizeof (Elf_External_Verdef);
3033 defaux.vda_name = h->dynstr_index;
3034 if (t->deps == NULL)
3035 defaux.vda_next = 0;
3036 else
3037 defaux.vda_next = sizeof (Elf_External_Verdaux);
3038 t->name_indx = defaux.vda_name;
3040 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3041 (Elf_External_Verdaux *) p);
3042 p += sizeof (Elf_External_Verdaux);
3044 for (n = t->deps; n != NULL; n = n->next)
3046 if (n->version_needed == NULL)
3048 /* This can happen if there was an error in the
3049 version script. */
3050 defaux.vda_name = 0;
3052 else
3053 defaux.vda_name = n->version_needed->name_indx;
3054 if (n->next == NULL)
3055 defaux.vda_next = 0;
3056 else
3057 defaux.vda_next = sizeof (Elf_External_Verdaux);
3059 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3060 (Elf_External_Verdaux *) p);
3061 p += sizeof (Elf_External_Verdaux);
3065 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3066 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3067 return false;
3069 elf_tdata (output_bfd)->cverdefs = cdefs;
3072 /* Work out the size of the version reference section. */
3074 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3075 BFD_ASSERT (s != NULL);
3077 struct elf_find_verdep_info sinfo;
3079 sinfo.output_bfd = output_bfd;
3080 sinfo.info = info;
3081 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3082 if (sinfo.vers == 0)
3083 sinfo.vers = 1;
3084 sinfo.failed = false;
3086 elf_link_hash_traverse (elf_hash_table (info),
3087 elf_link_find_version_dependencies,
3088 (PTR) &sinfo);
3090 if (elf_tdata (output_bfd)->verref == NULL)
3091 _bfd_strip_section_from_output (info, s);
3092 else
3094 Elf_Internal_Verneed *t;
3095 unsigned int size;
3096 unsigned int crefs;
3097 bfd_byte *p;
3099 /* Build the version definition section. */
3100 size = 0;
3101 crefs = 0;
3102 for (t = elf_tdata (output_bfd)->verref;
3103 t != NULL;
3104 t = t->vn_nextref)
3106 Elf_Internal_Vernaux *a;
3108 size += sizeof (Elf_External_Verneed);
3109 ++crefs;
3110 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3111 size += sizeof (Elf_External_Vernaux);
3114 s->_raw_size = size;
3115 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3116 if (s->contents == NULL)
3117 return false;
3119 p = s->contents;
3120 for (t = elf_tdata (output_bfd)->verref;
3121 t != NULL;
3122 t = t->vn_nextref)
3124 unsigned int caux;
3125 Elf_Internal_Vernaux *a;
3126 bfd_size_type indx;
3128 caux = 0;
3129 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3130 ++caux;
3132 t->vn_version = VER_NEED_CURRENT;
3133 t->vn_cnt = caux;
3134 if (elf_dt_name (t->vn_bfd) != NULL)
3135 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3136 elf_dt_name (t->vn_bfd),
3137 true, false);
3138 else
3139 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3140 t->vn_bfd->filename, true, false);
3141 if (indx == (bfd_size_type) -1)
3142 return false;
3143 t->vn_file = indx;
3144 t->vn_aux = sizeof (Elf_External_Verneed);
3145 if (t->vn_nextref == NULL)
3146 t->vn_next = 0;
3147 else
3148 t->vn_next = (sizeof (Elf_External_Verneed)
3149 + caux * sizeof (Elf_External_Vernaux));
3151 _bfd_elf_swap_verneed_out (output_bfd, t,
3152 (Elf_External_Verneed *) p);
3153 p += sizeof (Elf_External_Verneed);
3155 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3157 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3158 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3159 a->vna_nodename, true, false);
3160 if (indx == (bfd_size_type) -1)
3161 return false;
3162 a->vna_name = indx;
3163 if (a->vna_nextptr == NULL)
3164 a->vna_next = 0;
3165 else
3166 a->vna_next = sizeof (Elf_External_Vernaux);
3168 _bfd_elf_swap_vernaux_out (output_bfd, a,
3169 (Elf_External_Vernaux *) p);
3170 p += sizeof (Elf_External_Vernaux);
3174 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3175 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3176 return false;
3178 elf_tdata (output_bfd)->cverrefs = crefs;
3182 /* Assign dynsym indicies. In a shared library we generate a
3183 section symbol for each output section, which come first.
3184 Next come all of the back-end allocated local dynamic syms,
3185 followed by the rest of the global symbols. */
3187 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3189 /* Work out the size of the symbol version section. */
3190 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3191 BFD_ASSERT (s != NULL);
3192 if (dynsymcount == 0
3193 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3195 _bfd_strip_section_from_output (info, s);
3196 /* The DYNSYMCOUNT might have changed if we were going to
3197 output a dynamic symbol table entry for S. */
3198 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3200 else
3202 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3203 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3204 if (s->contents == NULL)
3205 return false;
3207 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3208 return false;
3211 /* Set the size of the .dynsym and .hash sections. We counted
3212 the number of dynamic symbols in elf_link_add_object_symbols.
3213 We will build the contents of .dynsym and .hash when we build
3214 the final symbol table, because until then we do not know the
3215 correct value to give the symbols. We built the .dynstr
3216 section as we went along in elf_link_add_object_symbols. */
3217 s = bfd_get_section_by_name (dynobj, ".dynsym");
3218 BFD_ASSERT (s != NULL);
3219 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3220 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3221 if (s->contents == NULL && s->_raw_size != 0)
3222 return false;
3224 /* The first entry in .dynsym is a dummy symbol. */
3225 isym.st_value = 0;
3226 isym.st_size = 0;
3227 isym.st_name = 0;
3228 isym.st_info = 0;
3229 isym.st_other = 0;
3230 isym.st_shndx = 0;
3231 elf_swap_symbol_out (output_bfd, &isym,
3232 (PTR) (Elf_External_Sym *) s->contents);
3234 /* Compute the size of the hashing table. As a side effect this
3235 computes the hash values for all the names we export. */
3236 bucketcount = compute_bucket_count (info);
3238 s = bfd_get_section_by_name (dynobj, ".hash");
3239 BFD_ASSERT (s != NULL);
3240 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3241 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3242 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3243 if (s->contents == NULL)
3244 return false;
3245 memset (s->contents, 0, (size_t) s->_raw_size);
3247 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3248 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3249 s->contents + hash_entry_size);
3251 elf_hash_table (info)->bucketcount = bucketcount;
3253 s = bfd_get_section_by_name (dynobj, ".dynstr");
3254 BFD_ASSERT (s != NULL);
3255 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3257 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3258 return false;
3261 return true;
3264 /* Fix up the flags for a symbol. This handles various cases which
3265 can only be fixed after all the input files are seen. This is
3266 currently called by both adjust_dynamic_symbol and
3267 assign_sym_version, which is unnecessary but perhaps more robust in
3268 the face of future changes. */
3270 static boolean
3271 elf_fix_symbol_flags (h, eif)
3272 struct elf_link_hash_entry *h;
3273 struct elf_info_failed *eif;
3275 /* If this symbol was mentioned in a non-ELF file, try to set
3276 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3277 permit a non-ELF file to correctly refer to a symbol defined in
3278 an ELF dynamic object. */
3279 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3281 if (h->root.type != bfd_link_hash_defined
3282 && h->root.type != bfd_link_hash_defweak)
3283 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3284 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3285 else
3287 if (h->root.u.def.section->owner != NULL
3288 && (bfd_get_flavour (h->root.u.def.section->owner)
3289 == bfd_target_elf_flavour))
3290 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3291 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3292 else
3293 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3296 if (h->dynindx == -1
3297 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3298 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3300 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3302 eif->failed = true;
3303 return false;
3307 else
3309 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3310 was first seen in a non-ELF file. Fortunately, if the symbol
3311 was first seen in an ELF file, we're probably OK unless the
3312 symbol was defined in a non-ELF file. Catch that case here.
3313 FIXME: We're still in trouble if the symbol was first seen in
3314 a dynamic object, and then later in a non-ELF regular object. */
3315 if ((h->root.type == bfd_link_hash_defined
3316 || h->root.type == bfd_link_hash_defweak)
3317 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3318 && (h->root.u.def.section->owner != NULL
3319 ? (bfd_get_flavour (h->root.u.def.section->owner)
3320 != bfd_target_elf_flavour)
3321 : (bfd_is_abs_section (h->root.u.def.section)
3322 && (h->elf_link_hash_flags
3323 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3324 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3327 /* If this is a final link, and the symbol was defined as a common
3328 symbol in a regular object file, and there was no definition in
3329 any dynamic object, then the linker will have allocated space for
3330 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3331 flag will not have been set. */
3332 if (h->root.type == bfd_link_hash_defined
3333 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3334 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3335 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3336 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3337 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3339 /* If -Bsymbolic was used (which means to bind references to global
3340 symbols to the definition within the shared object), and this
3341 symbol was defined in a regular object, then it actually doesn't
3342 need a PLT entry. */
3343 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3344 && eif->info->shared
3345 && eif->info->symbolic
3346 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3348 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3349 h->plt.offset = (bfd_vma) -1;
3352 /* If this is a weak defined symbol in a dynamic object, and we know
3353 the real definition in the dynamic object, copy interesting flags
3354 over to the real definition. */
3355 if (h->weakdef != NULL)
3357 struct elf_link_hash_entry *weakdef;
3359 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3360 || h->root.type == bfd_link_hash_defweak);
3361 weakdef = h->weakdef;
3362 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3363 || weakdef->root.type == bfd_link_hash_defweak);
3364 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3366 /* If the real definition is defined by a regular object file,
3367 don't do anything special. See the longer description in
3368 elf_adjust_dynamic_symbol, below. */
3369 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3370 h->weakdef = NULL;
3371 else
3372 weakdef->elf_link_hash_flags |=
3373 (h->elf_link_hash_flags
3374 & (ELF_LINK_HASH_REF_REGULAR
3375 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3376 | ELF_LINK_NON_GOT_REF));
3379 return true;
3382 /* Make the backend pick a good value for a dynamic symbol. This is
3383 called via elf_link_hash_traverse, and also calls itself
3384 recursively. */
3386 static boolean
3387 elf_adjust_dynamic_symbol (h, data)
3388 struct elf_link_hash_entry *h;
3389 PTR data;
3391 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3392 bfd *dynobj;
3393 struct elf_backend_data *bed;
3395 /* Ignore indirect symbols. These are added by the versioning code. */
3396 if (h->root.type == bfd_link_hash_indirect)
3397 return true;
3399 /* Fix the symbol flags. */
3400 if (! elf_fix_symbol_flags (h, eif))
3401 return false;
3403 /* If this symbol does not require a PLT entry, and it is not
3404 defined by a dynamic object, or is not referenced by a regular
3405 object, ignore it. We do have to handle a weak defined symbol,
3406 even if no regular object refers to it, if we decided to add it
3407 to the dynamic symbol table. FIXME: Do we normally need to worry
3408 about symbols which are defined by one dynamic object and
3409 referenced by another one? */
3410 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3411 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3412 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3413 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3414 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3416 h->plt.offset = (bfd_vma) -1;
3417 return true;
3420 /* If we've already adjusted this symbol, don't do it again. This
3421 can happen via a recursive call. */
3422 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3423 return true;
3425 /* Don't look at this symbol again. Note that we must set this
3426 after checking the above conditions, because we may look at a
3427 symbol once, decide not to do anything, and then get called
3428 recursively later after REF_REGULAR is set below. */
3429 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3431 /* If this is a weak definition, and we know a real definition, and
3432 the real symbol is not itself defined by a regular object file,
3433 then get a good value for the real definition. We handle the
3434 real symbol first, for the convenience of the backend routine.
3436 Note that there is a confusing case here. If the real definition
3437 is defined by a regular object file, we don't get the real symbol
3438 from the dynamic object, but we do get the weak symbol. If the
3439 processor backend uses a COPY reloc, then if some routine in the
3440 dynamic object changes the real symbol, we will not see that
3441 change in the corresponding weak symbol. This is the way other
3442 ELF linkers work as well, and seems to be a result of the shared
3443 library model.
3445 I will clarify this issue. Most SVR4 shared libraries define the
3446 variable _timezone and define timezone as a weak synonym. The
3447 tzset call changes _timezone. If you write
3448 extern int timezone;
3449 int _timezone = 5;
3450 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3451 you might expect that, since timezone is a synonym for _timezone,
3452 the same number will print both times. However, if the processor
3453 backend uses a COPY reloc, then actually timezone will be copied
3454 into your process image, and, since you define _timezone
3455 yourself, _timezone will not. Thus timezone and _timezone will
3456 wind up at different memory locations. The tzset call will set
3457 _timezone, leaving timezone unchanged. */
3459 if (h->weakdef != NULL)
3461 /* If we get to this point, we know there is an implicit
3462 reference by a regular object file via the weak symbol H.
3463 FIXME: Is this really true? What if the traversal finds
3464 H->WEAKDEF before it finds H? */
3465 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3467 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3468 return false;
3471 /* If a symbol has no type and no size and does not require a PLT
3472 entry, then we are probably about to do the wrong thing here: we
3473 are probably going to create a COPY reloc for an empty object.
3474 This case can arise when a shared object is built with assembly
3475 code, and the assembly code fails to set the symbol type. */
3476 if (h->size == 0
3477 && h->type == STT_NOTYPE
3478 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3479 (*_bfd_error_handler)
3480 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3481 h->root.root.string);
3483 dynobj = elf_hash_table (eif->info)->dynobj;
3484 bed = get_elf_backend_data (dynobj);
3485 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3487 eif->failed = true;
3488 return false;
3491 return true;
3494 /* This routine is used to export all defined symbols into the dynamic
3495 symbol table. It is called via elf_link_hash_traverse. */
3497 static boolean
3498 elf_export_symbol (h, data)
3499 struct elf_link_hash_entry *h;
3500 PTR data;
3502 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3504 /* Ignore indirect symbols. These are added by the versioning code. */
3505 if (h->root.type == bfd_link_hash_indirect)
3506 return true;
3508 if (h->dynindx == -1
3509 && (h->elf_link_hash_flags
3510 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3512 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3514 eif->failed = true;
3515 return false;
3519 return true;
3522 /* Look through the symbols which are defined in other shared
3523 libraries and referenced here. Update the list of version
3524 dependencies. This will be put into the .gnu.version_r section.
3525 This function is called via elf_link_hash_traverse. */
3527 static boolean
3528 elf_link_find_version_dependencies (h, data)
3529 struct elf_link_hash_entry *h;
3530 PTR data;
3532 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3533 Elf_Internal_Verneed *t;
3534 Elf_Internal_Vernaux *a;
3536 /* We only care about symbols defined in shared objects with version
3537 information. */
3538 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3539 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3540 || h->dynindx == -1
3541 || h->verinfo.verdef == NULL)
3542 return true;
3544 /* See if we already know about this version. */
3545 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3547 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3548 continue;
3550 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3551 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3552 return true;
3554 break;
3557 /* This is a new version. Add it to tree we are building. */
3559 if (t == NULL)
3561 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3562 if (t == NULL)
3564 rinfo->failed = true;
3565 return false;
3568 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3569 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3570 elf_tdata (rinfo->output_bfd)->verref = t;
3573 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3575 /* Note that we are copying a string pointer here, and testing it
3576 above. If bfd_elf_string_from_elf_section is ever changed to
3577 discard the string data when low in memory, this will have to be
3578 fixed. */
3579 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3581 a->vna_flags = h->verinfo.verdef->vd_flags;
3582 a->vna_nextptr = t->vn_auxptr;
3584 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3585 ++rinfo->vers;
3587 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3589 t->vn_auxptr = a;
3591 return true;
3594 /* Figure out appropriate versions for all the symbols. We may not
3595 have the version number script until we have read all of the input
3596 files, so until that point we don't know which symbols should be
3597 local. This function is called via elf_link_hash_traverse. */
3599 static boolean
3600 elf_link_assign_sym_version (h, data)
3601 struct elf_link_hash_entry *h;
3602 PTR data;
3604 struct elf_assign_sym_version_info *sinfo =
3605 (struct elf_assign_sym_version_info *) data;
3606 struct bfd_link_info *info = sinfo->info;
3607 struct elf_backend_data *bed;
3608 struct elf_info_failed eif;
3609 char *p;
3611 /* Fix the symbol flags. */
3612 eif.failed = false;
3613 eif.info = info;
3614 if (! elf_fix_symbol_flags (h, &eif))
3616 if (eif.failed)
3617 sinfo->failed = true;
3618 return false;
3621 /* We only need version numbers for symbols defined in regular
3622 objects. */
3623 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3624 return true;
3626 bed = get_elf_backend_data (sinfo->output_bfd);
3627 p = strchr (h->root.root.string, ELF_VER_CHR);
3628 if (p != NULL && h->verinfo.vertree == NULL)
3630 struct bfd_elf_version_tree *t;
3631 boolean hidden;
3633 hidden = true;
3635 /* There are two consecutive ELF_VER_CHR characters if this is
3636 not a hidden symbol. */
3637 ++p;
3638 if (*p == ELF_VER_CHR)
3640 hidden = false;
3641 ++p;
3644 /* If there is no version string, we can just return out. */
3645 if (*p == '\0')
3647 if (hidden)
3648 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3649 return true;
3652 /* Look for the version. If we find it, it is no longer weak. */
3653 for (t = sinfo->verdefs; t != NULL; t = t->next)
3655 if (strcmp (t->name, p) == 0)
3657 int len;
3658 char *alc;
3659 struct bfd_elf_version_expr *d;
3661 len = p - h->root.root.string;
3662 alc = bfd_alloc (sinfo->output_bfd, len);
3663 if (alc == NULL)
3664 return false;
3665 strncpy (alc, h->root.root.string, len - 1);
3666 alc[len - 1] = '\0';
3667 if (alc[len - 2] == ELF_VER_CHR)
3668 alc[len - 2] = '\0';
3670 h->verinfo.vertree = t;
3671 t->used = true;
3672 d = NULL;
3674 if (t->globals != NULL)
3676 for (d = t->globals; d != NULL; d = d->next)
3677 if ((*d->match) (d, alc))
3678 break;
3681 /* See if there is anything to force this symbol to
3682 local scope. */
3683 if (d == NULL && t->locals != NULL)
3685 for (d = t->locals; d != NULL; d = d->next)
3687 if ((*d->match) (d, alc))
3689 if (h->dynindx != -1
3690 && info->shared
3691 && ! sinfo->export_dynamic)
3693 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3694 (*bed->elf_backend_hide_symbol) (h);
3695 /* FIXME: The name of the symbol has
3696 already been recorded in the dynamic
3697 string table section. */
3700 break;
3705 bfd_release (sinfo->output_bfd, alc);
3706 break;
3710 /* If we are building an application, we need to create a
3711 version node for this version. */
3712 if (t == NULL && ! info->shared)
3714 struct bfd_elf_version_tree **pp;
3715 int version_index;
3717 /* If we aren't going to export this symbol, we don't need
3718 to worry about it. */
3719 if (h->dynindx == -1)
3720 return true;
3722 t = ((struct bfd_elf_version_tree *)
3723 bfd_alloc (sinfo->output_bfd, sizeof *t));
3724 if (t == NULL)
3726 sinfo->failed = true;
3727 return false;
3730 t->next = NULL;
3731 t->name = p;
3732 t->globals = NULL;
3733 t->locals = NULL;
3734 t->deps = NULL;
3735 t->name_indx = (unsigned int) -1;
3736 t->used = true;
3738 version_index = 1;
3739 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3740 ++version_index;
3741 t->vernum = version_index;
3743 *pp = t;
3745 h->verinfo.vertree = t;
3747 else if (t == NULL)
3749 /* We could not find the version for a symbol when
3750 generating a shared archive. Return an error. */
3751 (*_bfd_error_handler)
3752 (_("%s: undefined versioned symbol name %s"),
3753 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3754 bfd_set_error (bfd_error_bad_value);
3755 sinfo->failed = true;
3756 return false;
3759 if (hidden)
3760 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3763 /* If we don't have a version for this symbol, see if we can find
3764 something. */
3765 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3767 struct bfd_elf_version_tree *t;
3768 struct bfd_elf_version_tree *deflt;
3769 struct bfd_elf_version_expr *d;
3771 /* See if can find what version this symbol is in. If the
3772 symbol is supposed to be local, then don't actually register
3773 it. */
3774 deflt = NULL;
3775 for (t = sinfo->verdefs; t != NULL; t = t->next)
3777 if (t->globals != NULL)
3779 for (d = t->globals; d != NULL; d = d->next)
3781 if ((*d->match) (d, h->root.root.string))
3783 h->verinfo.vertree = t;
3784 break;
3788 if (d != NULL)
3789 break;
3792 if (t->locals != NULL)
3794 for (d = t->locals; d != NULL; d = d->next)
3796 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3797 deflt = t;
3798 else if ((*d->match) (d, h->root.root.string))
3800 h->verinfo.vertree = t;
3801 if (h->dynindx != -1
3802 && info->shared
3803 && ! sinfo->export_dynamic)
3805 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3806 (*bed->elf_backend_hide_symbol) (h);
3807 /* FIXME: The name of the symbol has already
3808 been recorded in the dynamic string table
3809 section. */
3811 break;
3815 if (d != NULL)
3816 break;
3820 if (deflt != NULL && h->verinfo.vertree == NULL)
3822 h->verinfo.vertree = deflt;
3823 if (h->dynindx != -1
3824 && info->shared
3825 && ! sinfo->export_dynamic)
3827 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3828 (*bed->elf_backend_hide_symbol) (h);
3829 /* FIXME: The name of the symbol has already been
3830 recorded in the dynamic string table section. */
3835 return true;
3838 /* Final phase of ELF linker. */
3840 /* A structure we use to avoid passing large numbers of arguments. */
3842 struct elf_final_link_info
3844 /* General link information. */
3845 struct bfd_link_info *info;
3846 /* Output BFD. */
3847 bfd *output_bfd;
3848 /* Symbol string table. */
3849 struct bfd_strtab_hash *symstrtab;
3850 /* .dynsym section. */
3851 asection *dynsym_sec;
3852 /* .hash section. */
3853 asection *hash_sec;
3854 /* symbol version section (.gnu.version). */
3855 asection *symver_sec;
3856 /* Buffer large enough to hold contents of any section. */
3857 bfd_byte *contents;
3858 /* Buffer large enough to hold external relocs of any section. */
3859 PTR external_relocs;
3860 /* Buffer large enough to hold internal relocs of any section. */
3861 Elf_Internal_Rela *internal_relocs;
3862 /* Buffer large enough to hold external local symbols of any input
3863 BFD. */
3864 Elf_External_Sym *external_syms;
3865 /* Buffer large enough to hold internal local symbols of any input
3866 BFD. */
3867 Elf_Internal_Sym *internal_syms;
3868 /* Array large enough to hold a symbol index for each local symbol
3869 of any input BFD. */
3870 long *indices;
3871 /* Array large enough to hold a section pointer for each local
3872 symbol of any input BFD. */
3873 asection **sections;
3874 /* Buffer to hold swapped out symbols. */
3875 Elf_External_Sym *symbuf;
3876 /* Number of swapped out symbols in buffer. */
3877 size_t symbuf_count;
3878 /* Number of symbols which fit in symbuf. */
3879 size_t symbuf_size;
3882 static boolean elf_link_output_sym
3883 PARAMS ((struct elf_final_link_info *, const char *,
3884 Elf_Internal_Sym *, asection *));
3885 static boolean elf_link_flush_output_syms
3886 PARAMS ((struct elf_final_link_info *));
3887 static boolean elf_link_output_extsym
3888 PARAMS ((struct elf_link_hash_entry *, PTR));
3889 static boolean elf_link_input_bfd
3890 PARAMS ((struct elf_final_link_info *, bfd *));
3891 static boolean elf_reloc_link_order
3892 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3893 struct bfd_link_order *));
3895 /* This struct is used to pass information to elf_link_output_extsym. */
3897 struct elf_outext_info
3899 boolean failed;
3900 boolean localsyms;
3901 struct elf_final_link_info *finfo;
3904 /* Compute the size of, and allocate space for, REL_HDR which is the
3905 section header for a section containing relocations for O. */
3907 static boolean
3908 elf_link_size_reloc_section (abfd, rel_hdr, o)
3909 bfd *abfd;
3910 Elf_Internal_Shdr *rel_hdr;
3911 asection *o;
3913 register struct elf_link_hash_entry **p, **pend;
3914 unsigned reloc_count;
3916 /* Figure out how many relocations there will be. */
3917 if (rel_hdr == &elf_section_data (o)->rel_hdr)
3918 reloc_count = elf_section_data (o)->rel_count;
3919 else
3920 reloc_count = elf_section_data (o)->rel_count2;
3922 /* That allows us to calculate the size of the section. */
3923 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
3925 /* The contents field must last into write_object_contents, so we
3926 allocate it with bfd_alloc rather than malloc. */
3927 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3928 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3929 return false;
3931 /* We only allocate one set of hash entries, so we only do it the
3932 first time we are called. */
3933 if (elf_section_data (o)->rel_hashes == NULL)
3935 p = ((struct elf_link_hash_entry **)
3936 bfd_malloc (o->reloc_count
3937 * sizeof (struct elf_link_hash_entry *)));
3938 if (p == NULL && o->reloc_count != 0)
3939 return false;
3941 elf_section_data (o)->rel_hashes = p;
3942 pend = p + o->reloc_count;
3943 for (; p < pend; p++)
3944 *p = NULL;
3947 return true;
3950 /* When performing a relocateable link, the input relocations are
3951 preserved. But, if they reference global symbols, the indices
3952 referenced must be updated. Update all the relocations in
3953 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
3955 static void
3956 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
3957 bfd *abfd;
3958 Elf_Internal_Shdr *rel_hdr;
3959 unsigned int count;
3960 struct elf_link_hash_entry **rel_hash;
3962 unsigned int i;
3964 for (i = 0; i < count; i++, rel_hash++)
3966 if (*rel_hash == NULL)
3967 continue;
3969 BFD_ASSERT ((*rel_hash)->indx >= 0);
3971 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3973 Elf_External_Rel *erel;
3974 Elf_Internal_Rel irel;
3976 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3977 elf_swap_reloc_in (abfd, erel, &irel);
3978 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3979 ELF_R_TYPE (irel.r_info));
3980 elf_swap_reloc_out (abfd, &irel, erel);
3982 else
3984 Elf_External_Rela *erela;
3985 Elf_Internal_Rela irela;
3987 BFD_ASSERT (rel_hdr->sh_entsize
3988 == sizeof (Elf_External_Rela));
3990 erela = (Elf_External_Rela *) rel_hdr->contents + i;
3991 elf_swap_reloca_in (abfd, erela, &irela);
3992 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
3993 ELF_R_TYPE (irela.r_info));
3994 elf_swap_reloca_out (abfd, &irela, erela);
3999 /* Do the final step of an ELF link. */
4001 boolean
4002 elf_bfd_final_link (abfd, info)
4003 bfd *abfd;
4004 struct bfd_link_info *info;
4006 boolean dynamic;
4007 bfd *dynobj;
4008 struct elf_final_link_info finfo;
4009 register asection *o;
4010 register struct bfd_link_order *p;
4011 register bfd *sub;
4012 size_t max_contents_size;
4013 size_t max_external_reloc_size;
4014 size_t max_internal_reloc_count;
4015 size_t max_sym_count;
4016 file_ptr off;
4017 Elf_Internal_Sym elfsym;
4018 unsigned int i;
4019 Elf_Internal_Shdr *symtab_hdr;
4020 Elf_Internal_Shdr *symstrtab_hdr;
4021 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4022 struct elf_outext_info eoinfo;
4024 if (info->shared)
4025 abfd->flags |= DYNAMIC;
4027 dynamic = elf_hash_table (info)->dynamic_sections_created;
4028 dynobj = elf_hash_table (info)->dynobj;
4030 finfo.info = info;
4031 finfo.output_bfd = abfd;
4032 finfo.symstrtab = elf_stringtab_init ();
4033 if (finfo.symstrtab == NULL)
4034 return false;
4036 if (! dynamic)
4038 finfo.dynsym_sec = NULL;
4039 finfo.hash_sec = NULL;
4040 finfo.symver_sec = NULL;
4042 else
4044 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4045 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4046 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4047 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4048 /* Note that it is OK if symver_sec is NULL. */
4051 finfo.contents = NULL;
4052 finfo.external_relocs = NULL;
4053 finfo.internal_relocs = NULL;
4054 finfo.external_syms = NULL;
4055 finfo.internal_syms = NULL;
4056 finfo.indices = NULL;
4057 finfo.sections = NULL;
4058 finfo.symbuf = NULL;
4059 finfo.symbuf_count = 0;
4061 /* Count up the number of relocations we will output for each output
4062 section, so that we know the sizes of the reloc sections. We
4063 also figure out some maximum sizes. */
4064 max_contents_size = 0;
4065 max_external_reloc_size = 0;
4066 max_internal_reloc_count = 0;
4067 max_sym_count = 0;
4068 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4070 o->reloc_count = 0;
4072 for (p = o->link_order_head; p != NULL; p = p->next)
4074 if (p->type == bfd_section_reloc_link_order
4075 || p->type == bfd_symbol_reloc_link_order)
4076 ++o->reloc_count;
4077 else if (p->type == bfd_indirect_link_order)
4079 asection *sec;
4081 sec = p->u.indirect.section;
4083 /* Mark all sections which are to be included in the
4084 link. This will normally be every section. We need
4085 to do this so that we can identify any sections which
4086 the linker has decided to not include. */
4087 sec->linker_mark = true;
4089 if (info->relocateable)
4090 o->reloc_count += sec->reloc_count;
4092 if (sec->_raw_size > max_contents_size)
4093 max_contents_size = sec->_raw_size;
4094 if (sec->_cooked_size > max_contents_size)
4095 max_contents_size = sec->_cooked_size;
4097 /* We are interested in just local symbols, not all
4098 symbols. */
4099 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4100 && (sec->owner->flags & DYNAMIC) == 0)
4102 size_t sym_count;
4104 if (elf_bad_symtab (sec->owner))
4105 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4106 / sizeof (Elf_External_Sym));
4107 else
4108 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4110 if (sym_count > max_sym_count)
4111 max_sym_count = sym_count;
4113 if ((sec->flags & SEC_RELOC) != 0)
4115 size_t ext_size;
4117 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4118 if (ext_size > max_external_reloc_size)
4119 max_external_reloc_size = ext_size;
4120 if (sec->reloc_count > max_internal_reloc_count)
4121 max_internal_reloc_count = sec->reloc_count;
4127 if (o->reloc_count > 0)
4128 o->flags |= SEC_RELOC;
4129 else
4131 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4132 set it (this is probably a bug) and if it is set
4133 assign_section_numbers will create a reloc section. */
4134 o->flags &=~ SEC_RELOC;
4137 /* If the SEC_ALLOC flag is not set, force the section VMA to
4138 zero. This is done in elf_fake_sections as well, but forcing
4139 the VMA to 0 here will ensure that relocs against these
4140 sections are handled correctly. */
4141 if ((o->flags & SEC_ALLOC) == 0
4142 && ! o->user_set_vma)
4143 o->vma = 0;
4146 /* Figure out the file positions for everything but the symbol table
4147 and the relocs. We set symcount to force assign_section_numbers
4148 to create a symbol table. */
4149 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4150 BFD_ASSERT (! abfd->output_has_begun);
4151 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4152 goto error_return;
4154 /* Figure out how many relocations we will have in each section.
4155 Just using RELOC_COUNT isn't good enough since that doesn't
4156 maintain a separate value for REL vs. RELA relocations. */
4157 if (info->relocateable)
4158 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4159 for (o = sub->sections; o != NULL; o = o->next)
4161 asection *output_section;
4163 if (! o->linker_mark)
4165 /* This section was omitted from the link. */
4166 continue;
4169 output_section = o->output_section;
4171 if (output_section != NULL
4172 && (o->flags & SEC_RELOC) != 0)
4174 struct bfd_elf_section_data *esdi
4175 = elf_section_data (o);
4176 struct bfd_elf_section_data *esdo
4177 = elf_section_data (output_section);
4178 unsigned int *rel_count;
4179 unsigned int *rel_count2;
4181 /* We must be careful to add the relocation froms the
4182 input section to the right output count. */
4183 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4185 rel_count = &esdo->rel_count;
4186 rel_count2 = &esdo->rel_count2;
4188 else
4190 rel_count = &esdo->rel_count2;
4191 rel_count2 = &esdo->rel_count;
4194 *rel_count += (esdi->rel_hdr.sh_size
4195 / esdi->rel_hdr.sh_entsize);
4196 if (esdi->rel_hdr2)
4197 *rel_count2 += (esdi->rel_hdr2->sh_size
4198 / esdi->rel_hdr2->sh_entsize);
4202 /* That created the reloc sections. Set their sizes, and assign
4203 them file positions, and allocate some buffers. */
4204 for (o = abfd->sections; o != NULL; o = o->next)
4206 if ((o->flags & SEC_RELOC) != 0)
4208 if (!elf_link_size_reloc_section (abfd,
4209 &elf_section_data (o)->rel_hdr,
4211 goto error_return;
4213 if (elf_section_data (o)->rel_hdr2
4214 && !elf_link_size_reloc_section (abfd,
4215 elf_section_data (o)->rel_hdr2,
4217 goto error_return;
4220 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4221 to count upwards while actually outputting the relocations. */
4222 elf_section_data (o)->rel_count = 0;
4223 elf_section_data (o)->rel_count2 = 0;
4226 _bfd_elf_assign_file_positions_for_relocs (abfd);
4228 /* We have now assigned file positions for all the sections except
4229 .symtab and .strtab. We start the .symtab section at the current
4230 file position, and write directly to it. We build the .strtab
4231 section in memory. */
4232 bfd_get_symcount (abfd) = 0;
4233 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4234 /* sh_name is set in prep_headers. */
4235 symtab_hdr->sh_type = SHT_SYMTAB;
4236 symtab_hdr->sh_flags = 0;
4237 symtab_hdr->sh_addr = 0;
4238 symtab_hdr->sh_size = 0;
4239 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4240 /* sh_link is set in assign_section_numbers. */
4241 /* sh_info is set below. */
4242 /* sh_offset is set just below. */
4243 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4245 off = elf_tdata (abfd)->next_file_pos;
4246 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4248 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4249 incorrect. We do not yet know the size of the .symtab section.
4250 We correct next_file_pos below, after we do know the size. */
4252 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4253 continuously seeking to the right position in the file. */
4254 if (! info->keep_memory || max_sym_count < 20)
4255 finfo.symbuf_size = 20;
4256 else
4257 finfo.symbuf_size = max_sym_count;
4258 finfo.symbuf = ((Elf_External_Sym *)
4259 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4260 if (finfo.symbuf == NULL)
4261 goto error_return;
4263 /* Start writing out the symbol table. The first symbol is always a
4264 dummy symbol. */
4265 if (info->strip != strip_all || info->relocateable)
4267 elfsym.st_value = 0;
4268 elfsym.st_size = 0;
4269 elfsym.st_info = 0;
4270 elfsym.st_other = 0;
4271 elfsym.st_shndx = SHN_UNDEF;
4272 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4273 &elfsym, bfd_und_section_ptr))
4274 goto error_return;
4277 #if 0
4278 /* Some standard ELF linkers do this, but we don't because it causes
4279 bootstrap comparison failures. */
4280 /* Output a file symbol for the output file as the second symbol.
4281 We output this even if we are discarding local symbols, although
4282 I'm not sure if this is correct. */
4283 elfsym.st_value = 0;
4284 elfsym.st_size = 0;
4285 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4286 elfsym.st_other = 0;
4287 elfsym.st_shndx = SHN_ABS;
4288 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4289 &elfsym, bfd_abs_section_ptr))
4290 goto error_return;
4291 #endif
4293 /* Output a symbol for each section. We output these even if we are
4294 discarding local symbols, since they are used for relocs. These
4295 symbols have no names. We store the index of each one in the
4296 index field of the section, so that we can find it again when
4297 outputting relocs. */
4298 if (info->strip != strip_all || info->relocateable)
4300 elfsym.st_size = 0;
4301 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4302 elfsym.st_other = 0;
4303 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4305 o = section_from_elf_index (abfd, i);
4306 if (o != NULL)
4307 o->target_index = bfd_get_symcount (abfd);
4308 elfsym.st_shndx = i;
4309 if (info->relocateable || o == NULL)
4310 elfsym.st_value = 0;
4311 else
4312 elfsym.st_value = o->vma;
4313 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4314 &elfsym, o))
4315 goto error_return;
4319 /* Allocate some memory to hold information read in from the input
4320 files. */
4321 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4322 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4323 finfo.internal_relocs = ((Elf_Internal_Rela *)
4324 bfd_malloc (max_internal_reloc_count
4325 * sizeof (Elf_Internal_Rela)
4326 * bed->s->int_rels_per_ext_rel));
4327 finfo.external_syms = ((Elf_External_Sym *)
4328 bfd_malloc (max_sym_count
4329 * sizeof (Elf_External_Sym)));
4330 finfo.internal_syms = ((Elf_Internal_Sym *)
4331 bfd_malloc (max_sym_count
4332 * sizeof (Elf_Internal_Sym)));
4333 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4334 finfo.sections = ((asection **)
4335 bfd_malloc (max_sym_count * sizeof (asection *)));
4336 if ((finfo.contents == NULL && max_contents_size != 0)
4337 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4338 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4339 || (finfo.external_syms == NULL && max_sym_count != 0)
4340 || (finfo.internal_syms == NULL && max_sym_count != 0)
4341 || (finfo.indices == NULL && max_sym_count != 0)
4342 || (finfo.sections == NULL && max_sym_count != 0))
4343 goto error_return;
4345 /* Since ELF permits relocations to be against local symbols, we
4346 must have the local symbols available when we do the relocations.
4347 Since we would rather only read the local symbols once, and we
4348 would rather not keep them in memory, we handle all the
4349 relocations for a single input file at the same time.
4351 Unfortunately, there is no way to know the total number of local
4352 symbols until we have seen all of them, and the local symbol
4353 indices precede the global symbol indices. This means that when
4354 we are generating relocateable output, and we see a reloc against
4355 a global symbol, we can not know the symbol index until we have
4356 finished examining all the local symbols to see which ones we are
4357 going to output. To deal with this, we keep the relocations in
4358 memory, and don't output them until the end of the link. This is
4359 an unfortunate waste of memory, but I don't see a good way around
4360 it. Fortunately, it only happens when performing a relocateable
4361 link, which is not the common case. FIXME: If keep_memory is set
4362 we could write the relocs out and then read them again; I don't
4363 know how bad the memory loss will be. */
4365 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4366 sub->output_has_begun = false;
4367 for (o = abfd->sections; o != NULL; o = o->next)
4369 for (p = o->link_order_head; p != NULL; p = p->next)
4371 if (p->type == bfd_indirect_link_order
4372 && (bfd_get_flavour (p->u.indirect.section->owner)
4373 == bfd_target_elf_flavour))
4375 sub = p->u.indirect.section->owner;
4376 if (! sub->output_has_begun)
4378 if (! elf_link_input_bfd (&finfo, sub))
4379 goto error_return;
4380 sub->output_has_begun = true;
4383 else if (p->type == bfd_section_reloc_link_order
4384 || p->type == bfd_symbol_reloc_link_order)
4386 if (! elf_reloc_link_order (abfd, info, o, p))
4387 goto error_return;
4389 else
4391 if (! _bfd_default_link_order (abfd, info, o, p))
4392 goto error_return;
4397 /* That wrote out all the local symbols. Finish up the symbol table
4398 with the global symbols. Even if we want to strip everything we
4399 can, we still need to deal with those global symbols that got
4400 converted to local in a version script. */
4402 if (info->shared)
4404 /* Output any global symbols that got converted to local in a
4405 version script. We do this in a separate step since ELF
4406 requires all local symbols to appear prior to any global
4407 symbols. FIXME: We should only do this if some global
4408 symbols were, in fact, converted to become local. FIXME:
4409 Will this work correctly with the Irix 5 linker? */
4410 eoinfo.failed = false;
4411 eoinfo.finfo = &finfo;
4412 eoinfo.localsyms = true;
4413 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4414 (PTR) &eoinfo);
4415 if (eoinfo.failed)
4416 return false;
4419 /* The sh_info field records the index of the first non local symbol. */
4420 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4422 if (dynamic)
4424 Elf_Internal_Sym sym;
4425 Elf_External_Sym *dynsym =
4426 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4427 long last_local = 0;
4429 /* Write out the section symbols for the output sections. */
4430 if (info->shared)
4432 asection *s;
4434 sym.st_size = 0;
4435 sym.st_name = 0;
4436 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4437 sym.st_other = 0;
4439 for (s = abfd->sections; s != NULL; s = s->next)
4441 int indx;
4442 indx = elf_section_data (s)->this_idx;
4443 BFD_ASSERT (indx > 0);
4444 sym.st_shndx = indx;
4445 sym.st_value = s->vma;
4447 elf_swap_symbol_out (abfd, &sym,
4448 dynsym + elf_section_data (s)->dynindx);
4451 last_local = bfd_count_sections (abfd);
4454 /* Write out the local dynsyms. */
4455 if (elf_hash_table (info)->dynlocal)
4457 struct elf_link_local_dynamic_entry *e;
4458 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4460 asection *s;
4462 sym.st_size = e->isym.st_size;
4463 sym.st_other = e->isym.st_other;
4465 /* Copy the internal symbol as is.
4466 Note that we saved a word of storage and overwrote
4467 the original st_name with the dynstr_index. */
4468 sym = e->isym;
4470 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4472 s = bfd_section_from_elf_index (e->input_bfd,
4473 e->isym.st_shndx);
4475 sym.st_shndx =
4476 elf_section_data (s->output_section)->this_idx;
4477 sym.st_value = (s->output_section->vma
4478 + s->output_offset
4479 + e->isym.st_value);
4482 if (last_local < e->dynindx)
4483 last_local = e->dynindx;
4485 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4489 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4490 last_local + 1;
4493 /* We get the global symbols from the hash table. */
4494 eoinfo.failed = false;
4495 eoinfo.localsyms = false;
4496 eoinfo.finfo = &finfo;
4497 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4498 (PTR) &eoinfo);
4499 if (eoinfo.failed)
4500 return false;
4502 /* If backend needs to output some symbols not present in the hash
4503 table, do it now. */
4504 if (bed->elf_backend_output_arch_syms)
4506 if (! (*bed->elf_backend_output_arch_syms)
4507 (abfd, info, (PTR) &finfo,
4508 (boolean (*) PARAMS ((PTR, const char *,
4509 Elf_Internal_Sym *, asection *)))
4510 elf_link_output_sym))
4511 return false;
4514 /* Flush all symbols to the file. */
4515 if (! elf_link_flush_output_syms (&finfo))
4516 return false;
4518 /* Now we know the size of the symtab section. */
4519 off += symtab_hdr->sh_size;
4521 /* Finish up and write out the symbol string table (.strtab)
4522 section. */
4523 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4524 /* sh_name was set in prep_headers. */
4525 symstrtab_hdr->sh_type = SHT_STRTAB;
4526 symstrtab_hdr->sh_flags = 0;
4527 symstrtab_hdr->sh_addr = 0;
4528 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4529 symstrtab_hdr->sh_entsize = 0;
4530 symstrtab_hdr->sh_link = 0;
4531 symstrtab_hdr->sh_info = 0;
4532 /* sh_offset is set just below. */
4533 symstrtab_hdr->sh_addralign = 1;
4535 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4536 elf_tdata (abfd)->next_file_pos = off;
4538 if (bfd_get_symcount (abfd) > 0)
4540 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4541 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4542 return false;
4545 /* Adjust the relocs to have the correct symbol indices. */
4546 for (o = abfd->sections; o != NULL; o = o->next)
4548 if ((o->flags & SEC_RELOC) == 0)
4549 continue;
4551 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4552 elf_section_data (o)->rel_count,
4553 elf_section_data (o)->rel_hashes);
4554 if (elf_section_data (o)->rel_hdr2 != NULL)
4555 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4556 elf_section_data (o)->rel_count2,
4557 (elf_section_data (o)->rel_hashes
4558 + elf_section_data (o)->rel_count));
4560 /* Set the reloc_count field to 0 to prevent write_relocs from
4561 trying to swap the relocs out itself. */
4562 o->reloc_count = 0;
4565 /* If we are linking against a dynamic object, or generating a
4566 shared library, finish up the dynamic linking information. */
4567 if (dynamic)
4569 Elf_External_Dyn *dyncon, *dynconend;
4571 /* Fix up .dynamic entries. */
4572 o = bfd_get_section_by_name (dynobj, ".dynamic");
4573 BFD_ASSERT (o != NULL);
4575 dyncon = (Elf_External_Dyn *) o->contents;
4576 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4577 for (; dyncon < dynconend; dyncon++)
4579 Elf_Internal_Dyn dyn;
4580 const char *name;
4581 unsigned int type;
4583 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4585 switch (dyn.d_tag)
4587 default:
4588 break;
4589 case DT_INIT:
4590 name = info->init_function;
4591 goto get_sym;
4592 case DT_FINI:
4593 name = info->fini_function;
4594 get_sym:
4596 struct elf_link_hash_entry *h;
4598 h = elf_link_hash_lookup (elf_hash_table (info), name,
4599 false, false, true);
4600 if (h != NULL
4601 && (h->root.type == bfd_link_hash_defined
4602 || h->root.type == bfd_link_hash_defweak))
4604 dyn.d_un.d_val = h->root.u.def.value;
4605 o = h->root.u.def.section;
4606 if (o->output_section != NULL)
4607 dyn.d_un.d_val += (o->output_section->vma
4608 + o->output_offset);
4609 else
4611 /* The symbol is imported from another shared
4612 library and does not apply to this one. */
4613 dyn.d_un.d_val = 0;
4616 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4619 break;
4621 case DT_HASH:
4622 name = ".hash";
4623 goto get_vma;
4624 case DT_STRTAB:
4625 name = ".dynstr";
4626 goto get_vma;
4627 case DT_SYMTAB:
4628 name = ".dynsym";
4629 goto get_vma;
4630 case DT_VERDEF:
4631 name = ".gnu.version_d";
4632 goto get_vma;
4633 case DT_VERNEED:
4634 name = ".gnu.version_r";
4635 goto get_vma;
4636 case DT_VERSYM:
4637 name = ".gnu.version";
4638 get_vma:
4639 o = bfd_get_section_by_name (abfd, name);
4640 BFD_ASSERT (o != NULL);
4641 dyn.d_un.d_ptr = o->vma;
4642 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4643 break;
4645 case DT_REL:
4646 case DT_RELA:
4647 case DT_RELSZ:
4648 case DT_RELASZ:
4649 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4650 type = SHT_REL;
4651 else
4652 type = SHT_RELA;
4653 dyn.d_un.d_val = 0;
4654 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4656 Elf_Internal_Shdr *hdr;
4658 hdr = elf_elfsections (abfd)[i];
4659 if (hdr->sh_type == type
4660 && (hdr->sh_flags & SHF_ALLOC) != 0)
4662 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4663 dyn.d_un.d_val += hdr->sh_size;
4664 else
4666 if (dyn.d_un.d_val == 0
4667 || hdr->sh_addr < dyn.d_un.d_val)
4668 dyn.d_un.d_val = hdr->sh_addr;
4672 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4673 break;
4678 /* If we have created any dynamic sections, then output them. */
4679 if (dynobj != NULL)
4681 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4682 goto error_return;
4684 for (o = dynobj->sections; o != NULL; o = o->next)
4686 if ((o->flags & SEC_HAS_CONTENTS) == 0
4687 || o->_raw_size == 0)
4688 continue;
4689 if ((o->flags & SEC_LINKER_CREATED) == 0)
4691 /* At this point, we are only interested in sections
4692 created by elf_link_create_dynamic_sections. */
4693 continue;
4695 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4696 != SHT_STRTAB)
4697 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4699 if (! bfd_set_section_contents (abfd, o->output_section,
4700 o->contents, o->output_offset,
4701 o->_raw_size))
4702 goto error_return;
4704 else
4706 file_ptr off;
4708 /* The contents of the .dynstr section are actually in a
4709 stringtab. */
4710 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4711 if (bfd_seek (abfd, off, SEEK_SET) != 0
4712 || ! _bfd_stringtab_emit (abfd,
4713 elf_hash_table (info)->dynstr))
4714 goto error_return;
4719 /* If we have optimized stabs strings, output them. */
4720 if (elf_hash_table (info)->stab_info != NULL)
4722 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4723 goto error_return;
4726 if (finfo.symstrtab != NULL)
4727 _bfd_stringtab_free (finfo.symstrtab);
4728 if (finfo.contents != NULL)
4729 free (finfo.contents);
4730 if (finfo.external_relocs != NULL)
4731 free (finfo.external_relocs);
4732 if (finfo.internal_relocs != NULL)
4733 free (finfo.internal_relocs);
4734 if (finfo.external_syms != NULL)
4735 free (finfo.external_syms);
4736 if (finfo.internal_syms != NULL)
4737 free (finfo.internal_syms);
4738 if (finfo.indices != NULL)
4739 free (finfo.indices);
4740 if (finfo.sections != NULL)
4741 free (finfo.sections);
4742 if (finfo.symbuf != NULL)
4743 free (finfo.symbuf);
4744 for (o = abfd->sections; o != NULL; o = o->next)
4746 if ((o->flags & SEC_RELOC) != 0
4747 && elf_section_data (o)->rel_hashes != NULL)
4748 free (elf_section_data (o)->rel_hashes);
4751 elf_tdata (abfd)->linker = true;
4753 return true;
4755 error_return:
4756 if (finfo.symstrtab != NULL)
4757 _bfd_stringtab_free (finfo.symstrtab);
4758 if (finfo.contents != NULL)
4759 free (finfo.contents);
4760 if (finfo.external_relocs != NULL)
4761 free (finfo.external_relocs);
4762 if (finfo.internal_relocs != NULL)
4763 free (finfo.internal_relocs);
4764 if (finfo.external_syms != NULL)
4765 free (finfo.external_syms);
4766 if (finfo.internal_syms != NULL)
4767 free (finfo.internal_syms);
4768 if (finfo.indices != NULL)
4769 free (finfo.indices);
4770 if (finfo.sections != NULL)
4771 free (finfo.sections);
4772 if (finfo.symbuf != NULL)
4773 free (finfo.symbuf);
4774 for (o = abfd->sections; o != NULL; o = o->next)
4776 if ((o->flags & SEC_RELOC) != 0
4777 && elf_section_data (o)->rel_hashes != NULL)
4778 free (elf_section_data (o)->rel_hashes);
4781 return false;
4784 /* Add a symbol to the output symbol table. */
4786 static boolean
4787 elf_link_output_sym (finfo, name, elfsym, input_sec)
4788 struct elf_final_link_info *finfo;
4789 const char *name;
4790 Elf_Internal_Sym *elfsym;
4791 asection *input_sec;
4793 boolean (*output_symbol_hook) PARAMS ((bfd *,
4794 struct bfd_link_info *info,
4795 const char *,
4796 Elf_Internal_Sym *,
4797 asection *));
4799 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4800 elf_backend_link_output_symbol_hook;
4801 if (output_symbol_hook != NULL)
4803 if (! ((*output_symbol_hook)
4804 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4805 return false;
4808 if (name == (const char *) NULL || *name == '\0')
4809 elfsym->st_name = 0;
4810 else if (input_sec->flags & SEC_EXCLUDE)
4811 elfsym->st_name = 0;
4812 else
4814 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4815 name, true,
4816 false);
4817 if (elfsym->st_name == (unsigned long) -1)
4818 return false;
4821 if (finfo->symbuf_count >= finfo->symbuf_size)
4823 if (! elf_link_flush_output_syms (finfo))
4824 return false;
4827 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4828 (PTR) (finfo->symbuf + finfo->symbuf_count));
4829 ++finfo->symbuf_count;
4831 ++ bfd_get_symcount (finfo->output_bfd);
4833 return true;
4836 /* Flush the output symbols to the file. */
4838 static boolean
4839 elf_link_flush_output_syms (finfo)
4840 struct elf_final_link_info *finfo;
4842 if (finfo->symbuf_count > 0)
4844 Elf_Internal_Shdr *symtab;
4846 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4848 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4849 SEEK_SET) != 0
4850 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4851 sizeof (Elf_External_Sym), finfo->output_bfd)
4852 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4853 return false;
4855 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4857 finfo->symbuf_count = 0;
4860 return true;
4863 /* Add an external symbol to the symbol table. This is called from
4864 the hash table traversal routine. When generating a shared object,
4865 we go through the symbol table twice. The first time we output
4866 anything that might have been forced to local scope in a version
4867 script. The second time we output the symbols that are still
4868 global symbols. */
4870 static boolean
4871 elf_link_output_extsym (h, data)
4872 struct elf_link_hash_entry *h;
4873 PTR data;
4875 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4876 struct elf_final_link_info *finfo = eoinfo->finfo;
4877 boolean strip;
4878 Elf_Internal_Sym sym;
4879 asection *input_sec;
4881 /* Decide whether to output this symbol in this pass. */
4882 if (eoinfo->localsyms)
4884 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4885 return true;
4887 else
4889 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4890 return true;
4893 /* If we are not creating a shared library, and this symbol is
4894 referenced by a shared library but is not defined anywhere, then
4895 warn that it is undefined. If we do not do this, the runtime
4896 linker will complain that the symbol is undefined when the
4897 program is run. We don't have to worry about symbols that are
4898 referenced by regular files, because we will already have issued
4899 warnings for them. */
4900 if (! finfo->info->relocateable
4901 && ! (finfo->info->shared
4902 && !finfo->info->no_undefined)
4903 && h->root.type == bfd_link_hash_undefined
4904 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4905 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4907 if (! ((*finfo->info->callbacks->undefined_symbol)
4908 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4909 (asection *) NULL, 0, true)))
4911 eoinfo->failed = true;
4912 return false;
4916 /* We don't want to output symbols that have never been mentioned by
4917 a regular file, or that we have been told to strip. However, if
4918 h->indx is set to -2, the symbol is used by a reloc and we must
4919 output it. */
4920 if (h->indx == -2)
4921 strip = false;
4922 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4923 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4924 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4925 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4926 strip = true;
4927 else if (finfo->info->strip == strip_all
4928 || (finfo->info->strip == strip_some
4929 && bfd_hash_lookup (finfo->info->keep_hash,
4930 h->root.root.string,
4931 false, false) == NULL))
4932 strip = true;
4933 else
4934 strip = false;
4936 /* If we're stripping it, and it's not a dynamic symbol, there's
4937 nothing else to do unless it is a forced local symbol. */
4938 if (strip
4939 && h->dynindx == -1
4940 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4941 return true;
4943 sym.st_value = 0;
4944 sym.st_size = h->size;
4945 sym.st_other = h->other;
4946 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4947 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4948 else if (h->root.type == bfd_link_hash_undefweak
4949 || h->root.type == bfd_link_hash_defweak)
4950 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4951 else
4952 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4954 switch (h->root.type)
4956 default:
4957 case bfd_link_hash_new:
4958 abort ();
4959 return false;
4961 case bfd_link_hash_undefined:
4962 input_sec = bfd_und_section_ptr;
4963 sym.st_shndx = SHN_UNDEF;
4964 break;
4966 case bfd_link_hash_undefweak:
4967 input_sec = bfd_und_section_ptr;
4968 sym.st_shndx = SHN_UNDEF;
4969 break;
4971 case bfd_link_hash_defined:
4972 case bfd_link_hash_defweak:
4974 input_sec = h->root.u.def.section;
4975 if (input_sec->output_section != NULL)
4977 sym.st_shndx =
4978 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4979 input_sec->output_section);
4980 if (sym.st_shndx == (unsigned short) -1)
4982 (*_bfd_error_handler)
4983 (_("%s: could not find output section %s for input section %s"),
4984 bfd_get_filename (finfo->output_bfd),
4985 input_sec->output_section->name,
4986 input_sec->name);
4987 eoinfo->failed = true;
4988 return false;
4991 /* ELF symbols in relocateable files are section relative,
4992 but in nonrelocateable files they are virtual
4993 addresses. */
4994 sym.st_value = h->root.u.def.value + input_sec->output_offset;
4995 if (! finfo->info->relocateable)
4996 sym.st_value += input_sec->output_section->vma;
4998 else
5000 BFD_ASSERT (input_sec->owner == NULL
5001 || (input_sec->owner->flags & DYNAMIC) != 0);
5002 sym.st_shndx = SHN_UNDEF;
5003 input_sec = bfd_und_section_ptr;
5006 break;
5008 case bfd_link_hash_common:
5009 input_sec = h->root.u.c.p->section;
5010 sym.st_shndx = SHN_COMMON;
5011 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5012 break;
5014 case bfd_link_hash_indirect:
5015 /* These symbols are created by symbol versioning. They point
5016 to the decorated version of the name. For example, if the
5017 symbol foo@@GNU_1.2 is the default, which should be used when
5018 foo is used with no version, then we add an indirect symbol
5019 foo which points to foo@@GNU_1.2. We ignore these symbols,
5020 since the indirected symbol is already in the hash table. If
5021 the indirect symbol is non-ELF, fall through and output it. */
5022 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
5023 return true;
5025 /* Fall through. */
5026 case bfd_link_hash_warning:
5027 /* We can't represent these symbols in ELF, although a warning
5028 symbol may have come from a .gnu.warning.SYMBOL section. We
5029 just put the target symbol in the hash table. If the target
5030 symbol does not really exist, don't do anything. */
5031 if (h->root.u.i.link->type == bfd_link_hash_new)
5032 return true;
5033 return (elf_link_output_extsym
5034 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5037 /* Give the processor backend a chance to tweak the symbol value,
5038 and also to finish up anything that needs to be done for this
5039 symbol. */
5040 if ((h->dynindx != -1
5041 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5042 && elf_hash_table (finfo->info)->dynamic_sections_created)
5044 struct elf_backend_data *bed;
5046 bed = get_elf_backend_data (finfo->output_bfd);
5047 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5048 (finfo->output_bfd, finfo->info, h, &sym)))
5050 eoinfo->failed = true;
5051 return false;
5055 /* If we are marking the symbol as undefined, and there are no
5056 non-weak references to this symbol from a regular object, then
5057 mark the symbol as weak undefined; if there are non-weak
5058 references, mark the symbol as strong. We can't do this earlier,
5059 because it might not be marked as undefined until the
5060 finish_dynamic_symbol routine gets through with it. */
5061 if (sym.st_shndx == SHN_UNDEF
5062 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5063 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5064 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5066 int bindtype;
5068 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5069 bindtype = STB_GLOBAL;
5070 else
5071 bindtype = STB_WEAK;
5072 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5075 /* If this symbol should be put in the .dynsym section, then put it
5076 there now. We have already know the symbol index. We also fill
5077 in the entry in the .hash section. */
5078 if (h->dynindx != -1
5079 && elf_hash_table (finfo->info)->dynamic_sections_created)
5081 size_t bucketcount;
5082 size_t bucket;
5083 size_t hash_entry_size;
5084 bfd_byte *bucketpos;
5085 bfd_vma chain;
5087 sym.st_name = h->dynstr_index;
5089 elf_swap_symbol_out (finfo->output_bfd, &sym,
5090 (PTR) (((Elf_External_Sym *)
5091 finfo->dynsym_sec->contents)
5092 + h->dynindx));
5094 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5095 bucket = h->elf_hash_value % bucketcount;
5096 hash_entry_size
5097 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5098 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5099 + (bucket + 2) * hash_entry_size);
5100 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5101 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5102 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5103 ((bfd_byte *) finfo->hash_sec->contents
5104 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5106 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5108 Elf_Internal_Versym iversym;
5110 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5112 if (h->verinfo.verdef == NULL)
5113 iversym.vs_vers = 0;
5114 else
5115 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5117 else
5119 if (h->verinfo.vertree == NULL)
5120 iversym.vs_vers = 1;
5121 else
5122 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5125 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5126 iversym.vs_vers |= VERSYM_HIDDEN;
5128 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5129 (((Elf_External_Versym *)
5130 finfo->symver_sec->contents)
5131 + h->dynindx));
5135 /* If we're stripping it, then it was just a dynamic symbol, and
5136 there's nothing else to do. */
5137 if (strip)
5138 return true;
5140 h->indx = bfd_get_symcount (finfo->output_bfd);
5142 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5144 eoinfo->failed = true;
5145 return false;
5148 return true;
5151 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5152 originated from the section given by INPUT_REL_HDR) to the
5153 OUTPUT_BFD. */
5155 static void
5156 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5157 internal_relocs)
5158 bfd *output_bfd;
5159 asection *input_section;
5160 Elf_Internal_Shdr *input_rel_hdr;
5161 Elf_Internal_Rela *internal_relocs;
5163 Elf_Internal_Rela *irela;
5164 Elf_Internal_Rela *irelaend;
5165 Elf_Internal_Shdr *output_rel_hdr;
5166 asection *output_section;
5167 unsigned int *rel_countp = NULL;
5169 output_section = input_section->output_section;
5170 output_rel_hdr = NULL;
5172 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5173 == input_rel_hdr->sh_entsize)
5175 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5176 rel_countp = &elf_section_data (output_section)->rel_count;
5178 else if (elf_section_data (output_section)->rel_hdr2
5179 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5180 == input_rel_hdr->sh_entsize))
5182 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5183 rel_countp = &elf_section_data (output_section)->rel_count2;
5186 BFD_ASSERT (output_rel_hdr != NULL);
5188 irela = internal_relocs;
5189 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5190 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5192 Elf_External_Rel *erel;
5194 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5195 for (; irela < irelaend; irela++, erel++)
5197 Elf_Internal_Rel irel;
5199 irel.r_offset = irela->r_offset;
5200 irel.r_info = irela->r_info;
5201 BFD_ASSERT (irela->r_addend == 0);
5202 elf_swap_reloc_out (output_bfd, &irel, erel);
5205 else
5207 Elf_External_Rela *erela;
5209 BFD_ASSERT (input_rel_hdr->sh_entsize
5210 == sizeof (Elf_External_Rela));
5211 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5212 for (; irela < irelaend; irela++, erela++)
5213 elf_swap_reloca_out (output_bfd, irela, erela);
5216 /* Bump the counter, so that we know where to add the next set of
5217 relocations. */
5218 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5221 /* Link an input file into the linker output file. This function
5222 handles all the sections and relocations of the input file at once.
5223 This is so that we only have to read the local symbols once, and
5224 don't have to keep them in memory. */
5226 static boolean
5227 elf_link_input_bfd (finfo, input_bfd)
5228 struct elf_final_link_info *finfo;
5229 bfd *input_bfd;
5231 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5232 bfd *, asection *, bfd_byte *,
5233 Elf_Internal_Rela *,
5234 Elf_Internal_Sym *, asection **));
5235 bfd *output_bfd;
5236 Elf_Internal_Shdr *symtab_hdr;
5237 size_t locsymcount;
5238 size_t extsymoff;
5239 Elf_External_Sym *external_syms;
5240 Elf_External_Sym *esym;
5241 Elf_External_Sym *esymend;
5242 Elf_Internal_Sym *isym;
5243 long *pindex;
5244 asection **ppsection;
5245 asection *o;
5246 struct elf_backend_data *bed;
5248 output_bfd = finfo->output_bfd;
5249 bed = get_elf_backend_data (output_bfd);
5250 relocate_section = bed->elf_backend_relocate_section;
5252 /* If this is a dynamic object, we don't want to do anything here:
5253 we don't want the local symbols, and we don't want the section
5254 contents. */
5255 if ((input_bfd->flags & DYNAMIC) != 0)
5256 return true;
5258 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5259 if (elf_bad_symtab (input_bfd))
5261 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5262 extsymoff = 0;
5264 else
5266 locsymcount = symtab_hdr->sh_info;
5267 extsymoff = symtab_hdr->sh_info;
5270 /* Read the local symbols. */
5271 if (symtab_hdr->contents != NULL)
5272 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5273 else if (locsymcount == 0)
5274 external_syms = NULL;
5275 else
5277 external_syms = finfo->external_syms;
5278 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5279 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5280 locsymcount, input_bfd)
5281 != locsymcount * sizeof (Elf_External_Sym)))
5282 return false;
5285 /* Swap in the local symbols and write out the ones which we know
5286 are going into the output file. */
5287 esym = external_syms;
5288 esymend = esym + locsymcount;
5289 isym = finfo->internal_syms;
5290 pindex = finfo->indices;
5291 ppsection = finfo->sections;
5292 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5294 asection *isec;
5295 const char *name;
5296 Elf_Internal_Sym osym;
5298 elf_swap_symbol_in (input_bfd, esym, isym);
5299 *pindex = -1;
5301 if (elf_bad_symtab (input_bfd))
5303 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5305 *ppsection = NULL;
5306 continue;
5310 if (isym->st_shndx == SHN_UNDEF)
5311 isec = bfd_und_section_ptr;
5312 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5313 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5314 else if (isym->st_shndx == SHN_ABS)
5315 isec = bfd_abs_section_ptr;
5316 else if (isym->st_shndx == SHN_COMMON)
5317 isec = bfd_com_section_ptr;
5318 else
5320 /* Who knows? */
5321 isec = NULL;
5324 *ppsection = isec;
5326 /* Don't output the first, undefined, symbol. */
5327 if (esym == external_syms)
5328 continue;
5330 /* If we are stripping all symbols, we don't want to output this
5331 one. */
5332 if (finfo->info->strip == strip_all)
5333 continue;
5335 /* We never output section symbols. Instead, we use the section
5336 symbol of the corresponding section in the output file. */
5337 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5338 continue;
5340 /* If we are discarding all local symbols, we don't want to
5341 output this one. If we are generating a relocateable output
5342 file, then some of the local symbols may be required by
5343 relocs; we output them below as we discover that they are
5344 needed. */
5345 if (finfo->info->discard == discard_all)
5346 continue;
5348 /* If this symbol is defined in a section which we are
5349 discarding, we don't need to keep it, but note that
5350 linker_mark is only reliable for sections that have contents.
5351 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5352 as well as linker_mark. */
5353 if (isym->st_shndx > 0
5354 && isym->st_shndx < SHN_LORESERVE
5355 && isec != NULL
5356 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5357 || (! finfo->info->relocateable
5358 && (isec->flags & SEC_EXCLUDE) != 0)))
5359 continue;
5361 /* Get the name of the symbol. */
5362 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5363 isym->st_name);
5364 if (name == NULL)
5365 return false;
5367 /* See if we are discarding symbols with this name. */
5368 if ((finfo->info->strip == strip_some
5369 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5370 == NULL))
5371 || (finfo->info->discard == discard_l
5372 && bfd_is_local_label_name (input_bfd, name)))
5373 continue;
5375 /* If we get here, we are going to output this symbol. */
5377 osym = *isym;
5379 /* Adjust the section index for the output file. */
5380 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5381 isec->output_section);
5382 if (osym.st_shndx == (unsigned short) -1)
5383 return false;
5385 *pindex = bfd_get_symcount (output_bfd);
5387 /* ELF symbols in relocateable files are section relative, but
5388 in executable files they are virtual addresses. Note that
5389 this code assumes that all ELF sections have an associated
5390 BFD section with a reasonable value for output_offset; below
5391 we assume that they also have a reasonable value for
5392 output_section. Any special sections must be set up to meet
5393 these requirements. */
5394 osym.st_value += isec->output_offset;
5395 if (! finfo->info->relocateable)
5396 osym.st_value += isec->output_section->vma;
5398 if (! elf_link_output_sym (finfo, name, &osym, isec))
5399 return false;
5402 /* Relocate the contents of each section. */
5403 for (o = input_bfd->sections; o != NULL; o = o->next)
5405 bfd_byte *contents;
5407 if (! o->linker_mark)
5409 /* This section was omitted from the link. */
5410 continue;
5413 if ((o->flags & SEC_HAS_CONTENTS) == 0
5414 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5415 continue;
5417 if ((o->flags & SEC_LINKER_CREATED) != 0)
5419 /* Section was created by elf_link_create_dynamic_sections
5420 or somesuch. */
5421 continue;
5424 /* Get the contents of the section. They have been cached by a
5425 relaxation routine. Note that o is a section in an input
5426 file, so the contents field will not have been set by any of
5427 the routines which work on output files. */
5428 if (elf_section_data (o)->this_hdr.contents != NULL)
5429 contents = elf_section_data (o)->this_hdr.contents;
5430 else
5432 contents = finfo->contents;
5433 if (! bfd_get_section_contents (input_bfd, o, contents,
5434 (file_ptr) 0, o->_raw_size))
5435 return false;
5438 if ((o->flags & SEC_RELOC) != 0)
5440 Elf_Internal_Rela *internal_relocs;
5442 /* Get the swapped relocs. */
5443 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5444 (input_bfd, o, finfo->external_relocs,
5445 finfo->internal_relocs, false));
5446 if (internal_relocs == NULL
5447 && o->reloc_count > 0)
5448 return false;
5450 /* Relocate the section by invoking a back end routine.
5452 The back end routine is responsible for adjusting the
5453 section contents as necessary, and (if using Rela relocs
5454 and generating a relocateable output file) adjusting the
5455 reloc addend as necessary.
5457 The back end routine does not have to worry about setting
5458 the reloc address or the reloc symbol index.
5460 The back end routine is given a pointer to the swapped in
5461 internal symbols, and can access the hash table entries
5462 for the external symbols via elf_sym_hashes (input_bfd).
5464 When generating relocateable output, the back end routine
5465 must handle STB_LOCAL/STT_SECTION symbols specially. The
5466 output symbol is going to be a section symbol
5467 corresponding to the output section, which will require
5468 the addend to be adjusted. */
5470 if (! (*relocate_section) (output_bfd, finfo->info,
5471 input_bfd, o, contents,
5472 internal_relocs,
5473 finfo->internal_syms,
5474 finfo->sections))
5475 return false;
5477 if (finfo->info->relocateable)
5479 Elf_Internal_Rela *irela;
5480 Elf_Internal_Rela *irelaend;
5481 struct elf_link_hash_entry **rel_hash;
5482 Elf_Internal_Shdr *input_rel_hdr;
5484 /* Adjust the reloc addresses and symbol indices. */
5486 irela = internal_relocs;
5487 irelaend =
5488 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5489 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5490 + elf_section_data (o->output_section)->rel_count
5491 + elf_section_data (o->output_section)->rel_count2);
5492 for (; irela < irelaend; irela++, rel_hash++)
5494 unsigned long r_symndx;
5495 Elf_Internal_Sym *isym;
5496 asection *sec;
5498 irela->r_offset += o->output_offset;
5500 r_symndx = ELF_R_SYM (irela->r_info);
5502 if (r_symndx == 0)
5503 continue;
5505 if (r_symndx >= locsymcount
5506 || (elf_bad_symtab (input_bfd)
5507 && finfo->sections[r_symndx] == NULL))
5509 struct elf_link_hash_entry *rh;
5510 long indx;
5512 /* This is a reloc against a global symbol. We
5513 have not yet output all the local symbols, so
5514 we do not know the symbol index of any global
5515 symbol. We set the rel_hash entry for this
5516 reloc to point to the global hash table entry
5517 for this symbol. The symbol index is then
5518 set at the end of elf_bfd_final_link. */
5519 indx = r_symndx - extsymoff;
5520 rh = elf_sym_hashes (input_bfd)[indx];
5521 while (rh->root.type == bfd_link_hash_indirect
5522 || rh->root.type == bfd_link_hash_warning)
5523 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5525 /* Setting the index to -2 tells
5526 elf_link_output_extsym that this symbol is
5527 used by a reloc. */
5528 BFD_ASSERT (rh->indx < 0);
5529 rh->indx = -2;
5531 *rel_hash = rh;
5533 continue;
5536 /* This is a reloc against a local symbol. */
5538 *rel_hash = NULL;
5539 isym = finfo->internal_syms + r_symndx;
5540 sec = finfo->sections[r_symndx];
5541 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5543 /* I suppose the backend ought to fill in the
5544 section of any STT_SECTION symbol against a
5545 processor specific section. If we have
5546 discarded a section, the output_section will
5547 be the absolute section. */
5548 if (sec != NULL
5549 && (bfd_is_abs_section (sec)
5550 || (sec->output_section != NULL
5551 && bfd_is_abs_section (sec->output_section))))
5552 r_symndx = 0;
5553 else if (sec == NULL || sec->owner == NULL)
5555 bfd_set_error (bfd_error_bad_value);
5556 return false;
5558 else
5560 r_symndx = sec->output_section->target_index;
5561 BFD_ASSERT (r_symndx != 0);
5564 else
5566 if (finfo->indices[r_symndx] == -1)
5568 unsigned long link;
5569 const char *name;
5570 asection *osec;
5572 if (finfo->info->strip == strip_all)
5574 /* You can't do ld -r -s. */
5575 bfd_set_error (bfd_error_invalid_operation);
5576 return false;
5579 /* This symbol was skipped earlier, but
5580 since it is needed by a reloc, we
5581 must output it now. */
5582 link = symtab_hdr->sh_link;
5583 name = bfd_elf_string_from_elf_section (input_bfd,
5584 link,
5585 isym->st_name);
5586 if (name == NULL)
5587 return false;
5589 osec = sec->output_section;
5590 isym->st_shndx =
5591 _bfd_elf_section_from_bfd_section (output_bfd,
5592 osec);
5593 if (isym->st_shndx == (unsigned short) -1)
5594 return false;
5596 isym->st_value += sec->output_offset;
5597 if (! finfo->info->relocateable)
5598 isym->st_value += osec->vma;
5600 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5602 if (! elf_link_output_sym (finfo, name, isym, sec))
5603 return false;
5606 r_symndx = finfo->indices[r_symndx];
5609 irela->r_info = ELF_R_INFO (r_symndx,
5610 ELF_R_TYPE (irela->r_info));
5613 /* Swap out the relocs. */
5614 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5615 elf_link_output_relocs (output_bfd, o,
5616 input_rel_hdr,
5617 internal_relocs);
5618 internal_relocs
5619 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5620 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5621 if (input_rel_hdr)
5622 elf_link_output_relocs (output_bfd, o,
5623 input_rel_hdr,
5624 internal_relocs);
5628 /* Write out the modified section contents. */
5629 if (elf_section_data (o)->stab_info == NULL)
5631 if (! (o->flags & SEC_EXCLUDE) &&
5632 ! bfd_set_section_contents (output_bfd, o->output_section,
5633 contents, o->output_offset,
5634 (o->_cooked_size != 0
5635 ? o->_cooked_size
5636 : o->_raw_size)))
5637 return false;
5639 else
5641 if (! (_bfd_write_section_stabs
5642 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5643 o, &elf_section_data (o)->stab_info, contents)))
5644 return false;
5648 return true;
5651 /* Generate a reloc when linking an ELF file. This is a reloc
5652 requested by the linker, and does come from any input file. This
5653 is used to build constructor and destructor tables when linking
5654 with -Ur. */
5656 static boolean
5657 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5658 bfd *output_bfd;
5659 struct bfd_link_info *info;
5660 asection *output_section;
5661 struct bfd_link_order *link_order;
5663 reloc_howto_type *howto;
5664 long indx;
5665 bfd_vma offset;
5666 bfd_vma addend;
5667 struct elf_link_hash_entry **rel_hash_ptr;
5668 Elf_Internal_Shdr *rel_hdr;
5670 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5671 if (howto == NULL)
5673 bfd_set_error (bfd_error_bad_value);
5674 return false;
5677 addend = link_order->u.reloc.p->addend;
5679 /* Figure out the symbol index. */
5680 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5681 + elf_section_data (output_section)->rel_count
5682 + elf_section_data (output_section)->rel_count2);
5683 if (link_order->type == bfd_section_reloc_link_order)
5685 indx = link_order->u.reloc.p->u.section->target_index;
5686 BFD_ASSERT (indx != 0);
5687 *rel_hash_ptr = NULL;
5689 else
5691 struct elf_link_hash_entry *h;
5693 /* Treat a reloc against a defined symbol as though it were
5694 actually against the section. */
5695 h = ((struct elf_link_hash_entry *)
5696 bfd_wrapped_link_hash_lookup (output_bfd, info,
5697 link_order->u.reloc.p->u.name,
5698 false, false, true));
5699 if (h != NULL
5700 && (h->root.type == bfd_link_hash_defined
5701 || h->root.type == bfd_link_hash_defweak))
5703 asection *section;
5705 section = h->root.u.def.section;
5706 indx = section->output_section->target_index;
5707 *rel_hash_ptr = NULL;
5708 /* It seems that we ought to add the symbol value to the
5709 addend here, but in practice it has already been added
5710 because it was passed to constructor_callback. */
5711 addend += section->output_section->vma + section->output_offset;
5713 else if (h != NULL)
5715 /* Setting the index to -2 tells elf_link_output_extsym that
5716 this symbol is used by a reloc. */
5717 h->indx = -2;
5718 *rel_hash_ptr = h;
5719 indx = 0;
5721 else
5723 if (! ((*info->callbacks->unattached_reloc)
5724 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5725 (asection *) NULL, (bfd_vma) 0)))
5726 return false;
5727 indx = 0;
5731 /* If this is an inplace reloc, we must write the addend into the
5732 object file. */
5733 if (howto->partial_inplace && addend != 0)
5735 bfd_size_type size;
5736 bfd_reloc_status_type rstat;
5737 bfd_byte *buf;
5738 boolean ok;
5740 size = bfd_get_reloc_size (howto);
5741 buf = (bfd_byte *) bfd_zmalloc (size);
5742 if (buf == (bfd_byte *) NULL)
5743 return false;
5744 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5745 switch (rstat)
5747 case bfd_reloc_ok:
5748 break;
5749 default:
5750 case bfd_reloc_outofrange:
5751 abort ();
5752 case bfd_reloc_overflow:
5753 if (! ((*info->callbacks->reloc_overflow)
5754 (info,
5755 (link_order->type == bfd_section_reloc_link_order
5756 ? bfd_section_name (output_bfd,
5757 link_order->u.reloc.p->u.section)
5758 : link_order->u.reloc.p->u.name),
5759 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5760 (bfd_vma) 0)))
5762 free (buf);
5763 return false;
5765 break;
5767 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5768 (file_ptr) link_order->offset, size);
5769 free (buf);
5770 if (! ok)
5771 return false;
5774 /* The address of a reloc is relative to the section in a
5775 relocateable file, and is a virtual address in an executable
5776 file. */
5777 offset = link_order->offset;
5778 if (! info->relocateable)
5779 offset += output_section->vma;
5781 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5783 if (rel_hdr->sh_type == SHT_REL)
5785 Elf_Internal_Rel irel;
5786 Elf_External_Rel *erel;
5788 irel.r_offset = offset;
5789 irel.r_info = ELF_R_INFO (indx, howto->type);
5790 erel = ((Elf_External_Rel *) rel_hdr->contents
5791 + elf_section_data (output_section)->rel_count);
5792 elf_swap_reloc_out (output_bfd, &irel, erel);
5794 else
5796 Elf_Internal_Rela irela;
5797 Elf_External_Rela *erela;
5799 irela.r_offset = offset;
5800 irela.r_info = ELF_R_INFO (indx, howto->type);
5801 irela.r_addend = addend;
5802 erela = ((Elf_External_Rela *) rel_hdr->contents
5803 + elf_section_data (output_section)->rel_count);
5804 elf_swap_reloca_out (output_bfd, &irela, erela);
5807 ++elf_section_data (output_section)->rel_count;
5809 return true;
5813 /* Allocate a pointer to live in a linker created section. */
5815 boolean
5816 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5817 bfd *abfd;
5818 struct bfd_link_info *info;
5819 elf_linker_section_t *lsect;
5820 struct elf_link_hash_entry *h;
5821 const Elf_Internal_Rela *rel;
5823 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5824 elf_linker_section_pointers_t *linker_section_ptr;
5825 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5827 BFD_ASSERT (lsect != NULL);
5829 /* Is this a global symbol? */
5830 if (h != NULL)
5832 /* Has this symbol already been allocated, if so, our work is done */
5833 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5834 rel->r_addend,
5835 lsect->which))
5836 return true;
5838 ptr_linker_section_ptr = &h->linker_section_pointer;
5839 /* Make sure this symbol is output as a dynamic symbol. */
5840 if (h->dynindx == -1)
5842 if (! elf_link_record_dynamic_symbol (info, h))
5843 return false;
5846 if (lsect->rel_section)
5847 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5850 else /* Allocation of a pointer to a local symbol */
5852 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5854 /* Allocate a table to hold the local symbols if first time */
5855 if (!ptr)
5857 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5858 register unsigned int i;
5860 ptr = (elf_linker_section_pointers_t **)
5861 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5863 if (!ptr)
5864 return false;
5866 elf_local_ptr_offsets (abfd) = ptr;
5867 for (i = 0; i < num_symbols; i++)
5868 ptr[i] = (elf_linker_section_pointers_t *)0;
5871 /* Has this symbol already been allocated, if so, our work is done */
5872 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5873 rel->r_addend,
5874 lsect->which))
5875 return true;
5877 ptr_linker_section_ptr = &ptr[r_symndx];
5879 if (info->shared)
5881 /* If we are generating a shared object, we need to
5882 output a R_<xxx>_RELATIVE reloc so that the
5883 dynamic linker can adjust this GOT entry. */
5884 BFD_ASSERT (lsect->rel_section != NULL);
5885 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5889 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5890 from internal memory. */
5891 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5892 linker_section_ptr = (elf_linker_section_pointers_t *)
5893 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5895 if (!linker_section_ptr)
5896 return false;
5898 linker_section_ptr->next = *ptr_linker_section_ptr;
5899 linker_section_ptr->addend = rel->r_addend;
5900 linker_section_ptr->which = lsect->which;
5901 linker_section_ptr->written_address_p = false;
5902 *ptr_linker_section_ptr = linker_section_ptr;
5904 #if 0
5905 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5907 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5908 lsect->hole_offset += ARCH_SIZE / 8;
5909 lsect->sym_offset += ARCH_SIZE / 8;
5910 if (lsect->sym_hash) /* Bump up symbol value if needed */
5912 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5913 #ifdef DEBUG
5914 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5915 lsect->sym_hash->root.root.string,
5916 (long)ARCH_SIZE / 8,
5917 (long)lsect->sym_hash->root.u.def.value);
5918 #endif
5921 else
5922 #endif
5923 linker_section_ptr->offset = lsect->section->_raw_size;
5925 lsect->section->_raw_size += ARCH_SIZE / 8;
5927 #ifdef DEBUG
5928 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5929 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5930 #endif
5932 return true;
5936 #if ARCH_SIZE==64
5937 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5938 #endif
5939 #if ARCH_SIZE==32
5940 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5941 #endif
5943 /* Fill in the address for a pointer generated in alinker section. */
5945 bfd_vma
5946 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5947 bfd *output_bfd;
5948 bfd *input_bfd;
5949 struct bfd_link_info *info;
5950 elf_linker_section_t *lsect;
5951 struct elf_link_hash_entry *h;
5952 bfd_vma relocation;
5953 const Elf_Internal_Rela *rel;
5954 int relative_reloc;
5956 elf_linker_section_pointers_t *linker_section_ptr;
5958 BFD_ASSERT (lsect != NULL);
5960 if (h != NULL) /* global symbol */
5962 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5963 rel->r_addend,
5964 lsect->which);
5966 BFD_ASSERT (linker_section_ptr != NULL);
5968 if (! elf_hash_table (info)->dynamic_sections_created
5969 || (info->shared
5970 && info->symbolic
5971 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5973 /* This is actually a static link, or it is a
5974 -Bsymbolic link and the symbol is defined
5975 locally. We must initialize this entry in the
5976 global section.
5978 When doing a dynamic link, we create a .rela.<xxx>
5979 relocation entry to initialize the value. This
5980 is done in the finish_dynamic_symbol routine. */
5981 if (!linker_section_ptr->written_address_p)
5983 linker_section_ptr->written_address_p = true;
5984 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5985 lsect->section->contents + linker_section_ptr->offset);
5989 else /* local symbol */
5991 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
5992 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
5993 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
5994 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
5995 rel->r_addend,
5996 lsect->which);
5998 BFD_ASSERT (linker_section_ptr != NULL);
6000 /* Write out pointer if it hasn't been rewritten out before */
6001 if (!linker_section_ptr->written_address_p)
6003 linker_section_ptr->written_address_p = true;
6004 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6005 lsect->section->contents + linker_section_ptr->offset);
6007 if (info->shared)
6009 asection *srel = lsect->rel_section;
6010 Elf_Internal_Rela outrel;
6012 /* We need to generate a relative reloc for the dynamic linker. */
6013 if (!srel)
6014 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6015 lsect->rel_name);
6017 BFD_ASSERT (srel != NULL);
6019 outrel.r_offset = (lsect->section->output_section->vma
6020 + lsect->section->output_offset
6021 + linker_section_ptr->offset);
6022 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6023 outrel.r_addend = 0;
6024 elf_swap_reloca_out (output_bfd, &outrel,
6025 (((Elf_External_Rela *)
6026 lsect->section->contents)
6027 + elf_section_data (lsect->section)->rel_count));
6028 ++elf_section_data (lsect->section)->rel_count;
6033 relocation = (lsect->section->output_offset
6034 + linker_section_ptr->offset
6035 - lsect->hole_offset
6036 - lsect->sym_offset);
6038 #ifdef DEBUG
6039 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6040 lsect->name, (long)relocation, (long)relocation);
6041 #endif
6043 /* Subtract out the addend, because it will get added back in by the normal
6044 processing. */
6045 return relocation - linker_section_ptr->addend;
6048 /* Garbage collect unused sections. */
6050 static boolean elf_gc_mark
6051 PARAMS ((struct bfd_link_info *info, asection *sec,
6052 asection * (*gc_mark_hook)
6053 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6054 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6056 static boolean elf_gc_sweep
6057 PARAMS ((struct bfd_link_info *info,
6058 boolean (*gc_sweep_hook)
6059 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6060 const Elf_Internal_Rela *relocs))));
6062 static boolean elf_gc_sweep_symbol
6063 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6065 static boolean elf_gc_allocate_got_offsets
6066 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6068 static boolean elf_gc_propagate_vtable_entries_used
6069 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6071 static boolean elf_gc_smash_unused_vtentry_relocs
6072 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6074 /* The mark phase of garbage collection. For a given section, mark
6075 it, and all the sections which define symbols to which it refers. */
6077 static boolean
6078 elf_gc_mark (info, sec, gc_mark_hook)
6079 struct bfd_link_info *info;
6080 asection *sec;
6081 asection * (*gc_mark_hook)
6082 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6083 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6085 boolean ret = true;
6087 sec->gc_mark = 1;
6089 /* Look through the section relocs. */
6091 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6093 Elf_Internal_Rela *relstart, *rel, *relend;
6094 Elf_Internal_Shdr *symtab_hdr;
6095 struct elf_link_hash_entry **sym_hashes;
6096 size_t nlocsyms;
6097 size_t extsymoff;
6098 Elf_External_Sym *locsyms, *freesyms = NULL;
6099 bfd *input_bfd = sec->owner;
6100 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6102 /* GCFIXME: how to arrange so that relocs and symbols are not
6103 reread continually? */
6105 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6106 sym_hashes = elf_sym_hashes (input_bfd);
6108 /* Read the local symbols. */
6109 if (elf_bad_symtab (input_bfd))
6111 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6112 extsymoff = 0;
6114 else
6115 extsymoff = nlocsyms = symtab_hdr->sh_info;
6116 if (symtab_hdr->contents)
6117 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6118 else if (nlocsyms == 0)
6119 locsyms = NULL;
6120 else
6122 locsyms = freesyms =
6123 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6124 if (freesyms == NULL
6125 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6126 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6127 nlocsyms, input_bfd)
6128 != nlocsyms * sizeof (Elf_External_Sym)))
6130 ret = false;
6131 goto out1;
6135 /* Read the relocations. */
6136 relstart = (NAME(_bfd_elf,link_read_relocs)
6137 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6138 info->keep_memory));
6139 if (relstart == NULL)
6141 ret = false;
6142 goto out1;
6144 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6146 for (rel = relstart; rel < relend; rel++)
6148 unsigned long r_symndx;
6149 asection *rsec;
6150 struct elf_link_hash_entry *h;
6151 Elf_Internal_Sym s;
6153 r_symndx = ELF_R_SYM (rel->r_info);
6154 if (r_symndx == 0)
6155 continue;
6157 if (elf_bad_symtab (sec->owner))
6159 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6160 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6161 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6162 else
6164 h = sym_hashes[r_symndx - extsymoff];
6165 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6168 else if (r_symndx >= nlocsyms)
6170 h = sym_hashes[r_symndx - extsymoff];
6171 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6173 else
6175 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6176 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6179 if (rsec && !rsec->gc_mark)
6180 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6182 ret = false;
6183 goto out2;
6187 out2:
6188 if (!info->keep_memory)
6189 free (relstart);
6190 out1:
6191 if (freesyms)
6192 free (freesyms);
6195 return ret;
6198 /* The sweep phase of garbage collection. Remove all garbage sections. */
6200 static boolean
6201 elf_gc_sweep (info, gc_sweep_hook)
6202 struct bfd_link_info *info;
6203 boolean (*gc_sweep_hook)
6204 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6205 const Elf_Internal_Rela *relocs));
6207 bfd *sub;
6209 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6211 asection *o;
6213 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6214 continue;
6216 for (o = sub->sections; o != NULL; o = o->next)
6218 /* Keep special sections. Keep .debug sections. */
6219 if ((o->flags & SEC_LINKER_CREATED)
6220 || (o->flags & SEC_DEBUGGING))
6221 o->gc_mark = 1;
6223 if (o->gc_mark)
6224 continue;
6226 /* Skip sweeping sections already excluded. */
6227 if (o->flags & SEC_EXCLUDE)
6228 continue;
6230 /* Since this is early in the link process, it is simple
6231 to remove a section from the output. */
6232 o->flags |= SEC_EXCLUDE;
6234 /* But we also have to update some of the relocation
6235 info we collected before. */
6236 if (gc_sweep_hook
6237 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6239 Elf_Internal_Rela *internal_relocs;
6240 boolean r;
6242 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6243 (o->owner, o, NULL, NULL, info->keep_memory));
6244 if (internal_relocs == NULL)
6245 return false;
6247 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6249 if (!info->keep_memory)
6250 free (internal_relocs);
6252 if (!r)
6253 return false;
6258 /* Remove the symbols that were in the swept sections from the dynamic
6259 symbol table. GCFIXME: Anyone know how to get them out of the
6260 static symbol table as well? */
6262 int i = 0;
6264 elf_link_hash_traverse (elf_hash_table (info),
6265 elf_gc_sweep_symbol,
6266 (PTR) &i);
6268 elf_hash_table (info)->dynsymcount = i;
6271 return true;
6274 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6276 static boolean
6277 elf_gc_sweep_symbol (h, idxptr)
6278 struct elf_link_hash_entry *h;
6279 PTR idxptr;
6281 int *idx = (int *) idxptr;
6283 if (h->dynindx != -1
6284 && ((h->root.type != bfd_link_hash_defined
6285 && h->root.type != bfd_link_hash_defweak)
6286 || h->root.u.def.section->gc_mark))
6287 h->dynindx = (*idx)++;
6289 return true;
6292 /* Propogate collected vtable information. This is called through
6293 elf_link_hash_traverse. */
6295 static boolean
6296 elf_gc_propagate_vtable_entries_used (h, okp)
6297 struct elf_link_hash_entry *h;
6298 PTR okp;
6300 /* Those that are not vtables. */
6301 if (h->vtable_parent == NULL)
6302 return true;
6304 /* Those vtables that do not have parents, we cannot merge. */
6305 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6306 return true;
6308 /* If we've already been done, exit. */
6309 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6310 return true;
6312 /* Make sure the parent's table is up to date. */
6313 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6315 if (h->vtable_entries_used == NULL)
6317 /* None of this table's entries were referenced. Re-use the
6318 parent's table. */
6319 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6320 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6322 else
6324 size_t n;
6325 boolean *cu, *pu;
6327 /* Or the parent's entries into ours. */
6328 cu = h->vtable_entries_used;
6329 cu[-1] = true;
6330 pu = h->vtable_parent->vtable_entries_used;
6331 if (pu != NULL)
6333 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6334 while (--n != 0)
6336 if (*pu) *cu = true;
6337 pu++, cu++;
6342 return true;
6345 static boolean
6346 elf_gc_smash_unused_vtentry_relocs (h, okp)
6347 struct elf_link_hash_entry *h;
6348 PTR okp;
6350 asection *sec;
6351 bfd_vma hstart, hend;
6352 Elf_Internal_Rela *relstart, *relend, *rel;
6353 struct elf_backend_data *bed;
6355 /* Take care of both those symbols that do not describe vtables as
6356 well as those that are not loaded. */
6357 if (h->vtable_parent == NULL)
6358 return true;
6360 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6361 || h->root.type == bfd_link_hash_defweak);
6363 sec = h->root.u.def.section;
6364 hstart = h->root.u.def.value;
6365 hend = hstart + h->size;
6367 relstart = (NAME(_bfd_elf,link_read_relocs)
6368 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6369 if (!relstart)
6370 return *(boolean *)okp = false;
6371 bed = get_elf_backend_data (sec->owner);
6372 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6374 for (rel = relstart; rel < relend; ++rel)
6375 if (rel->r_offset >= hstart && rel->r_offset < hend)
6377 /* If the entry is in use, do nothing. */
6378 if (h->vtable_entries_used
6379 && (rel->r_offset - hstart) < h->vtable_entries_size)
6381 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6382 if (h->vtable_entries_used[entry])
6383 continue;
6385 /* Otherwise, kill it. */
6386 rel->r_offset = rel->r_info = rel->r_addend = 0;
6389 return true;
6392 /* Do mark and sweep of unused sections. */
6394 boolean
6395 elf_gc_sections (abfd, info)
6396 bfd *abfd;
6397 struct bfd_link_info *info;
6399 boolean ok = true;
6400 bfd *sub;
6401 asection * (*gc_mark_hook)
6402 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6403 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6405 if (!get_elf_backend_data (abfd)->can_gc_sections
6406 || info->relocateable
6407 || elf_hash_table (info)->dynamic_sections_created)
6408 return true;
6410 /* Apply transitive closure to the vtable entry usage info. */
6411 elf_link_hash_traverse (elf_hash_table (info),
6412 elf_gc_propagate_vtable_entries_used,
6413 (PTR) &ok);
6414 if (!ok)
6415 return false;
6417 /* Kill the vtable relocations that were not used. */
6418 elf_link_hash_traverse (elf_hash_table (info),
6419 elf_gc_smash_unused_vtentry_relocs,
6420 (PTR) &ok);
6421 if (!ok)
6422 return false;
6424 /* Grovel through relocs to find out who stays ... */
6426 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6427 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6429 asection *o;
6431 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6432 continue;
6434 for (o = sub->sections; o != NULL; o = o->next)
6436 if (o->flags & SEC_KEEP)
6437 if (!elf_gc_mark (info, o, gc_mark_hook))
6438 return false;
6442 /* ... and mark SEC_EXCLUDE for those that go. */
6443 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6444 return false;
6446 return true;
6449 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6451 boolean
6452 elf_gc_record_vtinherit (abfd, sec, h, offset)
6453 bfd *abfd;
6454 asection *sec;
6455 struct elf_link_hash_entry *h;
6456 bfd_vma offset;
6458 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6459 struct elf_link_hash_entry **search, *child;
6460 bfd_size_type extsymcount;
6462 /* The sh_info field of the symtab header tells us where the
6463 external symbols start. We don't care about the local symbols at
6464 this point. */
6465 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6466 if (!elf_bad_symtab (abfd))
6467 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6469 sym_hashes = elf_sym_hashes (abfd);
6470 sym_hashes_end = sym_hashes + extsymcount;
6472 /* Hunt down the child symbol, which is in this section at the same
6473 offset as the relocation. */
6474 for (search = sym_hashes; search != sym_hashes_end; ++search)
6476 if ((child = *search) != NULL
6477 && (child->root.type == bfd_link_hash_defined
6478 || child->root.type == bfd_link_hash_defweak)
6479 && child->root.u.def.section == sec
6480 && child->root.u.def.value == offset)
6481 goto win;
6484 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6485 bfd_get_filename (abfd), sec->name,
6486 (unsigned long)offset);
6487 bfd_set_error (bfd_error_invalid_operation);
6488 return false;
6490 win:
6491 if (!h)
6493 /* This *should* only be the absolute section. It could potentially
6494 be that someone has defined a non-global vtable though, which
6495 would be bad. It isn't worth paging in the local symbols to be
6496 sure though; that case should simply be handled by the assembler. */
6498 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6500 else
6501 child->vtable_parent = h;
6503 return true;
6506 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6508 boolean
6509 elf_gc_record_vtentry (abfd, sec, h, addend)
6510 bfd *abfd ATTRIBUTE_UNUSED;
6511 asection *sec ATTRIBUTE_UNUSED;
6512 struct elf_link_hash_entry *h;
6513 bfd_vma addend;
6515 if (addend >= h->vtable_entries_size)
6517 size_t size, bytes;
6518 boolean *ptr = h->vtable_entries_used;
6520 /* While the symbol is undefined, we have to be prepared to handle
6521 a zero size. */
6522 if (h->root.type == bfd_link_hash_undefined)
6523 size = addend;
6524 else
6526 size = h->size;
6527 if (size < addend)
6529 /* Oops! We've got a reference past the defined end of
6530 the table. This is probably a bug -- shall we warn? */
6531 size = addend;
6535 /* Allocate one extra entry for use as a "done" flag for the
6536 consolidation pass. */
6537 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6539 if (ptr)
6541 ptr = bfd_realloc (ptr - 1, bytes);
6543 if (ptr != NULL)
6545 size_t oldbytes;
6547 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6548 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6551 else
6552 ptr = bfd_zmalloc (bytes);
6554 if (ptr == NULL)
6555 return false;
6557 /* And arrange for that done flag to be at index -1. */
6558 h->vtable_entries_used = ptr + 1;
6559 h->vtable_entries_size = size;
6562 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6564 return true;
6567 /* And an accompanying bit to work out final got entry offsets once
6568 we're done. Should be called from final_link. */
6570 boolean
6571 elf_gc_common_finalize_got_offsets (abfd, info)
6572 bfd *abfd;
6573 struct bfd_link_info *info;
6575 bfd *i;
6576 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6577 bfd_vma gotoff;
6579 /* The GOT offset is relative to the .got section, but the GOT header is
6580 put into the .got.plt section, if the backend uses it. */
6581 if (bed->want_got_plt)
6582 gotoff = 0;
6583 else
6584 gotoff = bed->got_header_size;
6586 /* Do the local .got entries first. */
6587 for (i = info->input_bfds; i; i = i->link_next)
6589 bfd_signed_vma *local_got;
6590 bfd_size_type j, locsymcount;
6591 Elf_Internal_Shdr *symtab_hdr;
6593 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6594 continue;
6596 local_got = elf_local_got_refcounts (i);
6597 if (!local_got)
6598 continue;
6600 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6601 if (elf_bad_symtab (i))
6602 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6603 else
6604 locsymcount = symtab_hdr->sh_info;
6606 for (j = 0; j < locsymcount; ++j)
6608 if (local_got[j] > 0)
6610 local_got[j] = gotoff;
6611 gotoff += ARCH_SIZE / 8;
6613 else
6614 local_got[j] = (bfd_vma) -1;
6618 /* Then the global .got and .plt entries. */
6619 elf_link_hash_traverse (elf_hash_table (info),
6620 elf_gc_allocate_got_offsets,
6621 (PTR) &gotoff);
6622 return true;
6625 /* We need a special top-level link routine to convert got reference counts
6626 to real got offsets. */
6628 static boolean
6629 elf_gc_allocate_got_offsets (h, offarg)
6630 struct elf_link_hash_entry *h;
6631 PTR offarg;
6633 bfd_vma *off = (bfd_vma *) offarg;
6635 if (h->got.refcount > 0)
6637 h->got.offset = off[0];
6638 off[0] += ARCH_SIZE / 8;
6640 else
6641 h->got.offset = (bfd_vma) -1;
6643 return true;
6646 /* Many folk need no more in the way of final link than this, once
6647 got entry reference counting is enabled. */
6649 boolean
6650 elf_gc_common_final_link (abfd, info)
6651 bfd *abfd;
6652 struct bfd_link_info *info;
6654 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6655 return false;
6657 /* Invoke the regular ELF backend linker to do all the work. */
6658 return elf_bfd_final_link (abfd, info);
6661 /* This function will be called though elf_link_hash_traverse to store
6662 all hash value of the exported symbols in an array. */
6664 static boolean
6665 elf_collect_hash_codes (h, data)
6666 struct elf_link_hash_entry *h;
6667 PTR data;
6669 unsigned long **valuep = (unsigned long **) data;
6670 const char *name;
6671 char *p;
6672 unsigned long ha;
6673 char *alc = NULL;
6675 /* Ignore indirect symbols. These are added by the versioning code. */
6676 if (h->dynindx == -1)
6677 return true;
6679 name = h->root.root.string;
6680 p = strchr (name, ELF_VER_CHR);
6681 if (p != NULL)
6683 alc = bfd_malloc (p - name + 1);
6684 memcpy (alc, name, p - name);
6685 alc[p - name] = '\0';
6686 name = alc;
6689 /* Compute the hash value. */
6690 ha = bfd_elf_hash (name);
6692 /* Store the found hash value in the array given as the argument. */
6693 *(*valuep)++ = ha;
6695 /* And store it in the struct so that we can put it in the hash table
6696 later. */
6697 h->elf_hash_value = ha;
6699 if (alc != NULL)
6700 free (alc);
6702 return true;