Add field ``name'' to floatformat.
[binutils.git] / bfd / elflink.h
blobd09ad172a2ba28b801bf5d6507d23d26b3ece89a
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
4 This file is part of BFD, the Binary File Descriptor library.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20 /* ELF linker code. */
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
25 struct elf_info_failed
27 boolean failed;
28 struct bfd_link_info *info;
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
71 switch (bfd_get_format (abfd))
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
83 /* Return true iff this is a non-common definition of a symbol. */
84 static boolean
85 is_global_symbol_definition (abfd, sym)
86 bfd * abfd ATTRIBUTE_UNUSED;
87 Elf_Internal_Sym * sym;
89 /* Local symbols do not count, but target specific ones might. */
90 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
91 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
92 return false;
94 /* If the section is undefined, then so is the symbol. */
95 if (sym->st_shndx == SHN_UNDEF)
96 return false;
98 /* If the symbol is defined in the common section, then
99 it is a common definition and so does not count. */
100 if (sym->st_shndx == SHN_COMMON)
101 return false;
103 /* If the symbol is in a target specific section then we
104 must rely upon the backend to tell us what it is. */
105 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
106 /* FIXME - this function is not coded yet:
108 return _bfd_is_global_symbol_definition (abfd, sym);
110 Instead for now assume that the definition is not global,
111 Even if this is wrong, at least the linker will behave
112 in the same way that it used to do. */
113 return false;
115 return true;
119 /* Search the symbol table of the archive element of the archive ABFD
120 whoes archove map contains a mention of SYMDEF, and determine if
121 the symbol is defined in this element. */
122 static boolean
123 elf_link_is_defined_archive_symbol (abfd, symdef)
124 bfd * abfd;
125 carsym * symdef;
127 Elf_Internal_Shdr * hdr;
128 Elf_External_Sym * esym;
129 Elf_External_Sym * esymend;
130 Elf_External_Sym * buf = NULL;
131 size_t symcount;
132 size_t extsymcount;
133 size_t extsymoff;
134 boolean result = false;
136 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
137 if (abfd == (bfd *) NULL)
138 return false;
140 if (! bfd_check_format (abfd, bfd_object))
141 return false;
143 /* If we have already included the element containing this symbol in the
144 link then we do not need to include it again. Just claim that any symbol
145 it contains is not a definition, so that our caller will not decide to
146 (re)include this element. */
147 if (abfd->archive_pass)
148 return false;
150 /* Select the appropriate symbol table. */
151 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
152 hdr = &elf_tdata (abfd)->symtab_hdr;
153 else
154 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
156 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
158 /* The sh_info field of the symtab header tells us where the
159 external symbols start. We don't care about the local symbols. */
160 if (elf_bad_symtab (abfd))
162 extsymcount = symcount;
163 extsymoff = 0;
165 else
167 extsymcount = symcount - hdr->sh_info;
168 extsymoff = hdr->sh_info;
171 buf = ((Elf_External_Sym *)
172 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
173 if (buf == NULL && extsymcount != 0)
174 return false;
176 /* Read in the symbol table.
177 FIXME: This ought to be cached somewhere. */
178 if (bfd_seek (abfd,
179 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
180 SEEK_SET) != 0
181 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
182 != extsymcount * sizeof (Elf_External_Sym)))
184 free (buf);
185 return false;
188 /* Scan the symbol table looking for SYMDEF. */
189 esymend = buf + extsymcount;
190 for (esym = buf;
191 esym < esymend;
192 esym++)
194 Elf_Internal_Sym sym;
195 const char * name;
197 elf_swap_symbol_in (abfd, esym, & sym);
199 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
200 if (name == (const char *) NULL)
201 break;
203 if (strcmp (name, symdef->name) == 0)
205 result = is_global_symbol_definition (abfd, & sym);
206 break;
210 free (buf);
212 return result;
216 /* Add symbols from an ELF archive file to the linker hash table. We
217 don't use _bfd_generic_link_add_archive_symbols because of a
218 problem which arises on UnixWare. The UnixWare libc.so is an
219 archive which includes an entry libc.so.1 which defines a bunch of
220 symbols. The libc.so archive also includes a number of other
221 object files, which also define symbols, some of which are the same
222 as those defined in libc.so.1. Correct linking requires that we
223 consider each object file in turn, and include it if it defines any
224 symbols we need. _bfd_generic_link_add_archive_symbols does not do
225 this; it looks through the list of undefined symbols, and includes
226 any object file which defines them. When this algorithm is used on
227 UnixWare, it winds up pulling in libc.so.1 early and defining a
228 bunch of symbols. This means that some of the other objects in the
229 archive are not included in the link, which is incorrect since they
230 precede libc.so.1 in the archive.
232 Fortunately, ELF archive handling is simpler than that done by
233 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
234 oddities. In ELF, if we find a symbol in the archive map, and the
235 symbol is currently undefined, we know that we must pull in that
236 object file.
238 Unfortunately, we do have to make multiple passes over the symbol
239 table until nothing further is resolved. */
241 static boolean
242 elf_link_add_archive_symbols (abfd, info)
243 bfd *abfd;
244 struct bfd_link_info *info;
246 symindex c;
247 boolean *defined = NULL;
248 boolean *included = NULL;
249 carsym *symdefs;
250 boolean loop;
252 if (! bfd_has_map (abfd))
254 /* An empty archive is a special case. */
255 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
256 return true;
257 bfd_set_error (bfd_error_no_armap);
258 return false;
261 /* Keep track of all symbols we know to be already defined, and all
262 files we know to be already included. This is to speed up the
263 second and subsequent passes. */
264 c = bfd_ardata (abfd)->symdef_count;
265 if (c == 0)
266 return true;
267 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
268 included = (boolean *) bfd_malloc (c * sizeof (boolean));
269 if (defined == (boolean *) NULL || included == (boolean *) NULL)
270 goto error_return;
271 memset (defined, 0, c * sizeof (boolean));
272 memset (included, 0, c * sizeof (boolean));
274 symdefs = bfd_ardata (abfd)->symdefs;
278 file_ptr last;
279 symindex i;
280 carsym *symdef;
281 carsym *symdefend;
283 loop = false;
284 last = -1;
286 symdef = symdefs;
287 symdefend = symdef + c;
288 for (i = 0; symdef < symdefend; symdef++, i++)
290 struct elf_link_hash_entry *h;
291 bfd *element;
292 struct bfd_link_hash_entry *undefs_tail;
293 symindex mark;
295 if (defined[i] || included[i])
296 continue;
297 if (symdef->file_offset == last)
299 included[i] = true;
300 continue;
303 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
304 false, false, false);
306 if (h == NULL)
308 char *p, *copy;
310 /* If this is a default version (the name contains @@),
311 look up the symbol again without the version. The
312 effect is that references to the symbol without the
313 version will be matched by the default symbol in the
314 archive. */
316 p = strchr (symdef->name, ELF_VER_CHR);
317 if (p == NULL || p[1] != ELF_VER_CHR)
318 continue;
320 copy = bfd_alloc (abfd, p - symdef->name + 1);
321 if (copy == NULL)
322 goto error_return;
323 memcpy (copy, symdef->name, p - symdef->name);
324 copy[p - symdef->name] = '\0';
326 h = elf_link_hash_lookup (elf_hash_table (info), copy,
327 false, false, false);
329 bfd_release (abfd, copy);
332 if (h == NULL)
333 continue;
335 if (h->root.type == bfd_link_hash_common)
337 /* We currently have a common symbol. The archive map contains
338 a reference to this symbol, so we may want to include it. We
339 only want to include it however, if this archive element
340 contains a definition of the symbol, not just another common
341 declaration of it.
343 Unfortunately some archivers (including GNU ar) will put
344 declarations of common symbols into their archive maps, as
345 well as real definitions, so we cannot just go by the archive
346 map alone. Instead we must read in the element's symbol
347 table and check that to see what kind of symbol definition
348 this is. */
349 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
350 continue;
352 else if (h->root.type != bfd_link_hash_undefined)
354 if (h->root.type != bfd_link_hash_undefweak)
355 defined[i] = true;
356 continue;
359 /* We need to include this archive member. */
360 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
361 if (element == (bfd *) NULL)
362 goto error_return;
364 if (! bfd_check_format (element, bfd_object))
365 goto error_return;
367 /* Doublecheck that we have not included this object
368 already--it should be impossible, but there may be
369 something wrong with the archive. */
370 if (element->archive_pass != 0)
372 bfd_set_error (bfd_error_bad_value);
373 goto error_return;
375 element->archive_pass = 1;
377 undefs_tail = info->hash->undefs_tail;
379 if (! (*info->callbacks->add_archive_element) (info, element,
380 symdef->name))
381 goto error_return;
382 if (! elf_link_add_object_symbols (element, info))
383 goto error_return;
385 /* If there are any new undefined symbols, we need to make
386 another pass through the archive in order to see whether
387 they can be defined. FIXME: This isn't perfect, because
388 common symbols wind up on undefs_tail and because an
389 undefined symbol which is defined later on in this pass
390 does not require another pass. This isn't a bug, but it
391 does make the code less efficient than it could be. */
392 if (undefs_tail != info->hash->undefs_tail)
393 loop = true;
395 /* Look backward to mark all symbols from this object file
396 which we have already seen in this pass. */
397 mark = i;
400 included[mark] = true;
401 if (mark == 0)
402 break;
403 --mark;
405 while (symdefs[mark].file_offset == symdef->file_offset);
407 /* We mark subsequent symbols from this object file as we go
408 on through the loop. */
409 last = symdef->file_offset;
412 while (loop);
414 free (defined);
415 free (included);
417 return true;
419 error_return:
420 if (defined != (boolean *) NULL)
421 free (defined);
422 if (included != (boolean *) NULL)
423 free (included);
424 return false;
427 /* This function is called when we want to define a new symbol. It
428 handles the various cases which arise when we find a definition in
429 a dynamic object, or when there is already a definition in a
430 dynamic object. The new symbol is described by NAME, SYM, PSEC,
431 and PVALUE. We set SYM_HASH to the hash table entry. We set
432 OVERRIDE if the old symbol is overriding a new definition. We set
433 TYPE_CHANGE_OK if it is OK for the type to change. We set
434 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
435 change, we mean that we shouldn't warn if the type or size does
436 change. */
438 static boolean
439 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
440 override, type_change_ok, size_change_ok)
441 bfd *abfd;
442 struct bfd_link_info *info;
443 const char *name;
444 Elf_Internal_Sym *sym;
445 asection **psec;
446 bfd_vma *pvalue;
447 struct elf_link_hash_entry **sym_hash;
448 boolean *override;
449 boolean *type_change_ok;
450 boolean *size_change_ok;
452 asection *sec;
453 struct elf_link_hash_entry *h;
454 int bind;
455 bfd *oldbfd;
456 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
458 *override = false;
460 sec = *psec;
461 bind = ELF_ST_BIND (sym->st_info);
463 if (! bfd_is_und_section (sec))
464 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
465 else
466 h = ((struct elf_link_hash_entry *)
467 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
468 if (h == NULL)
469 return false;
470 *sym_hash = h;
472 /* This code is for coping with dynamic objects, and is only useful
473 if we are doing an ELF link. */
474 if (info->hash->creator != abfd->xvec)
475 return true;
477 /* For merging, we only care about real symbols. */
479 while (h->root.type == bfd_link_hash_indirect
480 || h->root.type == bfd_link_hash_warning)
481 h = (struct elf_link_hash_entry *) h->root.u.i.link;
483 /* If we just created the symbol, mark it as being an ELF symbol.
484 Other than that, there is nothing to do--there is no merge issue
485 with a newly defined symbol--so we just return. */
487 if (h->root.type == bfd_link_hash_new)
489 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
490 return true;
493 /* OLDBFD is a BFD associated with the existing symbol. */
495 switch (h->root.type)
497 default:
498 oldbfd = NULL;
499 break;
501 case bfd_link_hash_undefined:
502 case bfd_link_hash_undefweak:
503 oldbfd = h->root.u.undef.abfd;
504 break;
506 case bfd_link_hash_defined:
507 case bfd_link_hash_defweak:
508 oldbfd = h->root.u.def.section->owner;
509 break;
511 case bfd_link_hash_common:
512 oldbfd = h->root.u.c.p->section->owner;
513 break;
516 /* In cases involving weak versioned symbols, we may wind up trying
517 to merge a symbol with itself. Catch that here, to avoid the
518 confusion that results if we try to override a symbol with
519 itself. The additional tests catch cases like
520 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
521 dynamic object, which we do want to handle here. */
522 if (abfd == oldbfd
523 && ((abfd->flags & DYNAMIC) == 0
524 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
525 return true;
527 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
528 respectively, is from a dynamic object. */
530 if ((abfd->flags & DYNAMIC) != 0)
531 newdyn = true;
532 else
533 newdyn = false;
535 if (oldbfd != NULL)
536 olddyn = (oldbfd->flags & DYNAMIC) != 0;
537 else
539 asection *hsec;
541 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
542 indices used by MIPS ELF. */
543 switch (h->root.type)
545 default:
546 hsec = NULL;
547 break;
549 case bfd_link_hash_defined:
550 case bfd_link_hash_defweak:
551 hsec = h->root.u.def.section;
552 break;
554 case bfd_link_hash_common:
555 hsec = h->root.u.c.p->section;
556 break;
559 if (hsec == NULL)
560 olddyn = false;
561 else
562 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
565 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
566 respectively, appear to be a definition rather than reference. */
568 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
569 newdef = false;
570 else
571 newdef = true;
573 if (h->root.type == bfd_link_hash_undefined
574 || h->root.type == bfd_link_hash_undefweak
575 || h->root.type == bfd_link_hash_common)
576 olddef = false;
577 else
578 olddef = true;
580 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
581 symbol, respectively, appears to be a common symbol in a dynamic
582 object. If a symbol appears in an uninitialized section, and is
583 not weak, and is not a function, then it may be a common symbol
584 which was resolved when the dynamic object was created. We want
585 to treat such symbols specially, because they raise special
586 considerations when setting the symbol size: if the symbol
587 appears as a common symbol in a regular object, and the size in
588 the regular object is larger, we must make sure that we use the
589 larger size. This problematic case can always be avoided in C,
590 but it must be handled correctly when using Fortran shared
591 libraries.
593 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
594 likewise for OLDDYNCOMMON and OLDDEF.
596 Note that this test is just a heuristic, and that it is quite
597 possible to have an uninitialized symbol in a shared object which
598 is really a definition, rather than a common symbol. This could
599 lead to some minor confusion when the symbol really is a common
600 symbol in some regular object. However, I think it will be
601 harmless. */
603 if (newdyn
604 && newdef
605 && (sec->flags & SEC_ALLOC) != 0
606 && (sec->flags & SEC_LOAD) == 0
607 && sym->st_size > 0
608 && bind != STB_WEAK
609 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
610 newdyncommon = true;
611 else
612 newdyncommon = false;
614 if (olddyn
615 && olddef
616 && h->root.type == bfd_link_hash_defined
617 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
618 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
619 && (h->root.u.def.section->flags & SEC_LOAD) == 0
620 && h->size > 0
621 && h->type != STT_FUNC)
622 olddyncommon = true;
623 else
624 olddyncommon = false;
626 /* It's OK to change the type if either the existing symbol or the
627 new symbol is weak. */
629 if (h->root.type == bfd_link_hash_defweak
630 || h->root.type == bfd_link_hash_undefweak
631 || bind == STB_WEAK)
632 *type_change_ok = true;
634 /* It's OK to change the size if either the existing symbol or the
635 new symbol is weak, or if the old symbol is undefined. */
637 if (*type_change_ok
638 || h->root.type == bfd_link_hash_undefined)
639 *size_change_ok = true;
641 /* If both the old and the new symbols look like common symbols in a
642 dynamic object, set the size of the symbol to the larger of the
643 two. */
645 if (olddyncommon
646 && newdyncommon
647 && sym->st_size != h->size)
649 /* Since we think we have two common symbols, issue a multiple
650 common warning if desired. Note that we only warn if the
651 size is different. If the size is the same, we simply let
652 the old symbol override the new one as normally happens with
653 symbols defined in dynamic objects. */
655 if (! ((*info->callbacks->multiple_common)
656 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
657 h->size, abfd, bfd_link_hash_common, sym->st_size)))
658 return false;
660 if (sym->st_size > h->size)
661 h->size = sym->st_size;
663 *size_change_ok = true;
666 /* If we are looking at a dynamic object, and we have found a
667 definition, we need to see if the symbol was already defined by
668 some other object. If so, we want to use the existing
669 definition, and we do not want to report a multiple symbol
670 definition error; we do this by clobbering *PSEC to be
671 bfd_und_section_ptr.
673 We treat a common symbol as a definition if the symbol in the
674 shared library is a function, since common symbols always
675 represent variables; this can cause confusion in principle, but
676 any such confusion would seem to indicate an erroneous program or
677 shared library. We also permit a common symbol in a regular
678 object to override a weak symbol in a shared object.
680 We prefer a non-weak definition in a shared library to a weak
681 definition in the executable. */
683 if (newdyn
684 && newdef
685 && (olddef
686 || (h->root.type == bfd_link_hash_common
687 && (bind == STB_WEAK
688 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
689 && (h->root.type != bfd_link_hash_defweak
690 || bind == STB_WEAK))
692 *override = true;
693 newdef = false;
694 newdyncommon = false;
696 *psec = sec = bfd_und_section_ptr;
697 *size_change_ok = true;
699 /* If we get here when the old symbol is a common symbol, then
700 we are explicitly letting it override a weak symbol or
701 function in a dynamic object, and we don't want to warn about
702 a type change. If the old symbol is a defined symbol, a type
703 change warning may still be appropriate. */
705 if (h->root.type == bfd_link_hash_common)
706 *type_change_ok = true;
709 /* Handle the special case of an old common symbol merging with a
710 new symbol which looks like a common symbol in a shared object.
711 We change *PSEC and *PVALUE to make the new symbol look like a
712 common symbol, and let _bfd_generic_link_add_one_symbol will do
713 the right thing. */
715 if (newdyncommon
716 && h->root.type == bfd_link_hash_common)
718 *override = true;
719 newdef = false;
720 newdyncommon = false;
721 *pvalue = sym->st_size;
722 *psec = sec = bfd_com_section_ptr;
723 *size_change_ok = true;
726 /* If the old symbol is from a dynamic object, and the new symbol is
727 a definition which is not from a dynamic object, then the new
728 symbol overrides the old symbol. Symbols from regular files
729 always take precedence over symbols from dynamic objects, even if
730 they are defined after the dynamic object in the link.
732 As above, we again permit a common symbol in a regular object to
733 override a definition in a shared object if the shared object
734 symbol is a function or is weak.
736 As above, we permit a non-weak definition in a shared object to
737 override a weak definition in a regular object. */
739 if (! newdyn
740 && (newdef
741 || (bfd_is_com_section (sec)
742 && (h->root.type == bfd_link_hash_defweak
743 || h->type == STT_FUNC)))
744 && olddyn
745 && olddef
746 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
747 && (bind != STB_WEAK
748 || h->root.type == bfd_link_hash_defweak))
750 /* Change the hash table entry to undefined, and let
751 _bfd_generic_link_add_one_symbol do the right thing with the
752 new definition. */
754 h->root.type = bfd_link_hash_undefined;
755 h->root.u.undef.abfd = h->root.u.def.section->owner;
756 *size_change_ok = true;
758 olddef = false;
759 olddyncommon = false;
761 /* We again permit a type change when a common symbol may be
762 overriding a function. */
764 if (bfd_is_com_section (sec))
765 *type_change_ok = true;
767 /* This union may have been set to be non-NULL when this symbol
768 was seen in a dynamic object. We must force the union to be
769 NULL, so that it is correct for a regular symbol. */
771 h->verinfo.vertree = NULL;
773 /* In this special case, if H is the target of an indirection,
774 we want the caller to frob with H rather than with the
775 indirect symbol. That will permit the caller to redefine the
776 target of the indirection, rather than the indirect symbol
777 itself. FIXME: This will break the -y option if we store a
778 symbol with a different name. */
779 *sym_hash = h;
782 /* Handle the special case of a new common symbol merging with an
783 old symbol that looks like it might be a common symbol defined in
784 a shared object. Note that we have already handled the case in
785 which a new common symbol should simply override the definition
786 in the shared library. */
788 if (! newdyn
789 && bfd_is_com_section (sec)
790 && olddyncommon)
792 /* It would be best if we could set the hash table entry to a
793 common symbol, but we don't know what to use for the section
794 or the alignment. */
795 if (! ((*info->callbacks->multiple_common)
796 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
797 h->size, abfd, bfd_link_hash_common, sym->st_size)))
798 return false;
800 /* If the predumed common symbol in the dynamic object is
801 larger, pretend that the new symbol has its size. */
803 if (h->size > *pvalue)
804 *pvalue = h->size;
806 /* FIXME: We no longer know the alignment required by the symbol
807 in the dynamic object, so we just wind up using the one from
808 the regular object. */
810 olddef = false;
811 olddyncommon = false;
813 h->root.type = bfd_link_hash_undefined;
814 h->root.u.undef.abfd = h->root.u.def.section->owner;
816 *size_change_ok = true;
817 *type_change_ok = true;
819 h->verinfo.vertree = NULL;
822 /* Handle the special case of a weak definition in a regular object
823 followed by a non-weak definition in a shared object. In this
824 case, we prefer the definition in the shared object. */
825 if (olddef
826 && h->root.type == bfd_link_hash_defweak
827 && newdef
828 && newdyn
829 && bind != STB_WEAK)
831 /* To make this work we have to frob the flags so that the rest
832 of the code does not think we are using the regular
833 definition. */
834 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
835 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
836 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
837 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
838 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
839 | ELF_LINK_HASH_DEF_DYNAMIC);
841 /* If H is the target of an indirection, we want the caller to
842 use H rather than the indirect symbol. Otherwise if we are
843 defining a new indirect symbol we will wind up attaching it
844 to the entry we are overriding. */
845 *sym_hash = h;
848 /* Handle the special case of a non-weak definition in a shared
849 object followed by a weak definition in a regular object. In
850 this case we prefer to definition in the shared object. To make
851 this work we have to tell the caller to not treat the new symbol
852 as a definition. */
853 if (olddef
854 && olddyn
855 && h->root.type != bfd_link_hash_defweak
856 && newdef
857 && ! newdyn
858 && bind == STB_WEAK)
859 *override = true;
861 return true;
864 /* Add symbols from an ELF object file to the linker hash table. */
866 static boolean
867 elf_link_add_object_symbols (abfd, info)
868 bfd *abfd;
869 struct bfd_link_info *info;
871 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
872 const Elf_Internal_Sym *,
873 const char **, flagword *,
874 asection **, bfd_vma *));
875 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
876 asection *, const Elf_Internal_Rela *));
877 boolean collect;
878 Elf_Internal_Shdr *hdr;
879 size_t symcount;
880 size_t extsymcount;
881 size_t extsymoff;
882 Elf_External_Sym *buf = NULL;
883 struct elf_link_hash_entry **sym_hash;
884 boolean dynamic;
885 bfd_byte *dynver = NULL;
886 Elf_External_Versym *extversym = NULL;
887 Elf_External_Versym *ever;
888 Elf_External_Dyn *dynbuf = NULL;
889 struct elf_link_hash_entry *weaks;
890 Elf_External_Sym *esym;
891 Elf_External_Sym *esymend;
892 struct elf_backend_data *bed;
894 bed = get_elf_backend_data (abfd);
895 add_symbol_hook = bed->elf_add_symbol_hook;
896 collect = bed->collect;
898 if ((abfd->flags & DYNAMIC) == 0)
899 dynamic = false;
900 else
902 dynamic = true;
904 /* You can't use -r against a dynamic object. Also, there's no
905 hope of using a dynamic object which does not exactly match
906 the format of the output file. */
907 if (info->relocateable || info->hash->creator != abfd->xvec)
909 bfd_set_error (bfd_error_invalid_operation);
910 goto error_return;
914 /* As a GNU extension, any input sections which are named
915 .gnu.warning.SYMBOL are treated as warning symbols for the given
916 symbol. This differs from .gnu.warning sections, which generate
917 warnings when they are included in an output file. */
918 if (! info->shared)
920 asection *s;
922 for (s = abfd->sections; s != NULL; s = s->next)
924 const char *name;
926 name = bfd_get_section_name (abfd, s);
927 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
929 char *msg;
930 bfd_size_type sz;
932 name += sizeof ".gnu.warning." - 1;
934 /* If this is a shared object, then look up the symbol
935 in the hash table. If it is there, and it is already
936 been defined, then we will not be using the entry
937 from this shared object, so we don't need to warn.
938 FIXME: If we see the definition in a regular object
939 later on, we will warn, but we shouldn't. The only
940 fix is to keep track of what warnings we are supposed
941 to emit, and then handle them all at the end of the
942 link. */
943 if (dynamic && abfd->xvec == info->hash->creator)
945 struct elf_link_hash_entry *h;
947 h = elf_link_hash_lookup (elf_hash_table (info), name,
948 false, false, true);
950 /* FIXME: What about bfd_link_hash_common? */
951 if (h != NULL
952 && (h->root.type == bfd_link_hash_defined
953 || h->root.type == bfd_link_hash_defweak))
955 /* We don't want to issue this warning. Clobber
956 the section size so that the warning does not
957 get copied into the output file. */
958 s->_raw_size = 0;
959 continue;
963 sz = bfd_section_size (abfd, s);
964 msg = (char *) bfd_alloc (abfd, sz + 1);
965 if (msg == NULL)
966 goto error_return;
968 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
969 goto error_return;
971 msg[sz] = '\0';
973 if (! (_bfd_generic_link_add_one_symbol
974 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
975 false, collect, (struct bfd_link_hash_entry **) NULL)))
976 goto error_return;
978 if (! info->relocateable)
980 /* Clobber the section size so that the warning does
981 not get copied into the output file. */
982 s->_raw_size = 0;
988 /* If this is a dynamic object, we always link against the .dynsym
989 symbol table, not the .symtab symbol table. The dynamic linker
990 will only see the .dynsym symbol table, so there is no reason to
991 look at .symtab for a dynamic object. */
993 if (! dynamic || elf_dynsymtab (abfd) == 0)
994 hdr = &elf_tdata (abfd)->symtab_hdr;
995 else
996 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
998 if (dynamic)
1000 /* Read in any version definitions. */
1002 if (! _bfd_elf_slurp_version_tables (abfd))
1003 goto error_return;
1005 /* Read in the symbol versions, but don't bother to convert them
1006 to internal format. */
1007 if (elf_dynversym (abfd) != 0)
1009 Elf_Internal_Shdr *versymhdr;
1011 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1012 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1013 if (extversym == NULL)
1014 goto error_return;
1015 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1016 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1017 != versymhdr->sh_size))
1018 goto error_return;
1022 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1024 /* The sh_info field of the symtab header tells us where the
1025 external symbols start. We don't care about the local symbols at
1026 this point. */
1027 if (elf_bad_symtab (abfd))
1029 extsymcount = symcount;
1030 extsymoff = 0;
1032 else
1034 extsymcount = symcount - hdr->sh_info;
1035 extsymoff = hdr->sh_info;
1038 buf = ((Elf_External_Sym *)
1039 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1040 if (buf == NULL && extsymcount != 0)
1041 goto error_return;
1043 /* We store a pointer to the hash table entry for each external
1044 symbol. */
1045 sym_hash = ((struct elf_link_hash_entry **)
1046 bfd_alloc (abfd,
1047 extsymcount * sizeof (struct elf_link_hash_entry *)));
1048 if (sym_hash == NULL)
1049 goto error_return;
1050 elf_sym_hashes (abfd) = sym_hash;
1052 if (! dynamic)
1054 /* If we are creating a shared library, create all the dynamic
1055 sections immediately. We need to attach them to something,
1056 so we attach them to this BFD, provided it is the right
1057 format. FIXME: If there are no input BFD's of the same
1058 format as the output, we can't make a shared library. */
1059 if (info->shared
1060 && ! elf_hash_table (info)->dynamic_sections_created
1061 && abfd->xvec == info->hash->creator)
1063 if (! elf_link_create_dynamic_sections (abfd, info))
1064 goto error_return;
1067 else
1069 asection *s;
1070 boolean add_needed;
1071 const char *name;
1072 bfd_size_type oldsize;
1073 bfd_size_type strindex;
1075 /* Find the name to use in a DT_NEEDED entry that refers to this
1076 object. If the object has a DT_SONAME entry, we use it.
1077 Otherwise, if the generic linker stuck something in
1078 elf_dt_name, we use that. Otherwise, we just use the file
1079 name. If the generic linker put a null string into
1080 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1081 there is a DT_SONAME entry. */
1082 add_needed = true;
1083 name = bfd_get_filename (abfd);
1084 if (elf_dt_name (abfd) != NULL)
1086 name = elf_dt_name (abfd);
1087 if (*name == '\0')
1088 add_needed = false;
1090 s = bfd_get_section_by_name (abfd, ".dynamic");
1091 if (s != NULL)
1093 Elf_External_Dyn *extdyn;
1094 Elf_External_Dyn *extdynend;
1095 int elfsec;
1096 unsigned long link;
1098 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1099 if (dynbuf == NULL)
1100 goto error_return;
1102 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1103 (file_ptr) 0, s->_raw_size))
1104 goto error_return;
1106 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1107 if (elfsec == -1)
1108 goto error_return;
1109 link = elf_elfsections (abfd)[elfsec]->sh_link;
1112 /* The shared libraries distributed with hpux11 have a bogus
1113 sh_link field for the ".dynamic" section. This code detects
1114 when LINK refers to a section that is not a string table and
1115 tries to find the string table for the ".dynsym" section
1116 instead. */
1117 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1118 if (hdr->sh_type != SHT_STRTAB)
1120 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1121 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1122 if (elfsec == -1)
1123 goto error_return;
1124 link = elf_elfsections (abfd)[elfsec]->sh_link;
1128 extdyn = dynbuf;
1129 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1130 for (; extdyn < extdynend; extdyn++)
1132 Elf_Internal_Dyn dyn;
1134 elf_swap_dyn_in (abfd, extdyn, &dyn);
1135 if (dyn.d_tag == DT_SONAME)
1137 name = bfd_elf_string_from_elf_section (abfd, link,
1138 dyn.d_un.d_val);
1139 if (name == NULL)
1140 goto error_return;
1142 if (dyn.d_tag == DT_NEEDED)
1144 struct bfd_link_needed_list *n, **pn;
1145 char *fnm, *anm;
1147 n = ((struct bfd_link_needed_list *)
1148 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1149 fnm = bfd_elf_string_from_elf_section (abfd, link,
1150 dyn.d_un.d_val);
1151 if (n == NULL || fnm == NULL)
1152 goto error_return;
1153 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1154 if (anm == NULL)
1155 goto error_return;
1156 strcpy (anm, fnm);
1157 n->name = anm;
1158 n->by = abfd;
1159 n->next = NULL;
1160 for (pn = &elf_hash_table (info)->needed;
1161 *pn != NULL;
1162 pn = &(*pn)->next)
1164 *pn = n;
1168 free (dynbuf);
1169 dynbuf = NULL;
1172 /* We do not want to include any of the sections in a dynamic
1173 object in the output file. We hack by simply clobbering the
1174 list of sections in the BFD. This could be handled more
1175 cleanly by, say, a new section flag; the existing
1176 SEC_NEVER_LOAD flag is not the one we want, because that one
1177 still implies that the section takes up space in the output
1178 file. */
1179 abfd->sections = NULL;
1180 abfd->section_count = 0;
1182 /* If this is the first dynamic object found in the link, create
1183 the special sections required for dynamic linking. */
1184 if (! elf_hash_table (info)->dynamic_sections_created)
1186 if (! elf_link_create_dynamic_sections (abfd, info))
1187 goto error_return;
1190 if (add_needed)
1192 /* Add a DT_NEEDED entry for this dynamic object. */
1193 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1194 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1195 true, false);
1196 if (strindex == (bfd_size_type) -1)
1197 goto error_return;
1199 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1201 asection *sdyn;
1202 Elf_External_Dyn *dyncon, *dynconend;
1204 /* The hash table size did not change, which means that
1205 the dynamic object name was already entered. If we
1206 have already included this dynamic object in the
1207 link, just ignore it. There is no reason to include
1208 a particular dynamic object more than once. */
1209 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1210 ".dynamic");
1211 BFD_ASSERT (sdyn != NULL);
1213 dyncon = (Elf_External_Dyn *) sdyn->contents;
1214 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1215 sdyn->_raw_size);
1216 for (; dyncon < dynconend; dyncon++)
1218 Elf_Internal_Dyn dyn;
1220 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1221 &dyn);
1222 if (dyn.d_tag == DT_NEEDED
1223 && dyn.d_un.d_val == strindex)
1225 if (buf != NULL)
1226 free (buf);
1227 if (extversym != NULL)
1228 free (extversym);
1229 return true;
1234 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1235 goto error_return;
1238 /* Save the SONAME, if there is one, because sometimes the
1239 linker emulation code will need to know it. */
1240 if (*name == '\0')
1241 name = bfd_get_filename (abfd);
1242 elf_dt_name (abfd) = name;
1245 if (bfd_seek (abfd,
1246 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1247 SEEK_SET) != 0
1248 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1249 != extsymcount * sizeof (Elf_External_Sym)))
1250 goto error_return;
1252 weaks = NULL;
1254 ever = extversym != NULL ? extversym + extsymoff : NULL;
1255 esymend = buf + extsymcount;
1256 for (esym = buf;
1257 esym < esymend;
1258 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1260 Elf_Internal_Sym sym;
1261 int bind;
1262 bfd_vma value;
1263 asection *sec;
1264 flagword flags;
1265 const char *name;
1266 struct elf_link_hash_entry *h;
1267 boolean definition;
1268 boolean size_change_ok, type_change_ok;
1269 boolean new_weakdef;
1270 unsigned int old_alignment;
1272 elf_swap_symbol_in (abfd, esym, &sym);
1274 flags = BSF_NO_FLAGS;
1275 sec = NULL;
1276 value = sym.st_value;
1277 *sym_hash = NULL;
1279 bind = ELF_ST_BIND (sym.st_info);
1280 if (bind == STB_LOCAL)
1282 /* This should be impossible, since ELF requires that all
1283 global symbols follow all local symbols, and that sh_info
1284 point to the first global symbol. Unfortunatealy, Irix 5
1285 screws this up. */
1286 continue;
1288 else if (bind == STB_GLOBAL)
1290 if (sym.st_shndx != SHN_UNDEF
1291 && sym.st_shndx != SHN_COMMON)
1292 flags = BSF_GLOBAL;
1293 else
1294 flags = 0;
1296 else if (bind == STB_WEAK)
1297 flags = BSF_WEAK;
1298 else
1300 /* Leave it up to the processor backend. */
1303 if (sym.st_shndx == SHN_UNDEF)
1304 sec = bfd_und_section_ptr;
1305 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1307 sec = section_from_elf_index (abfd, sym.st_shndx);
1308 if (sec == NULL)
1309 sec = bfd_abs_section_ptr;
1310 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1311 value -= sec->vma;
1313 else if (sym.st_shndx == SHN_ABS)
1314 sec = bfd_abs_section_ptr;
1315 else if (sym.st_shndx == SHN_COMMON)
1317 sec = bfd_com_section_ptr;
1318 /* What ELF calls the size we call the value. What ELF
1319 calls the value we call the alignment. */
1320 value = sym.st_size;
1322 else
1324 /* Leave it up to the processor backend. */
1327 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1328 if (name == (const char *) NULL)
1329 goto error_return;
1331 if (add_symbol_hook)
1333 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1334 &value))
1335 goto error_return;
1337 /* The hook function sets the name to NULL if this symbol
1338 should be skipped for some reason. */
1339 if (name == (const char *) NULL)
1340 continue;
1343 /* Sanity check that all possibilities were handled. */
1344 if (sec == (asection *) NULL)
1346 bfd_set_error (bfd_error_bad_value);
1347 goto error_return;
1350 if (bfd_is_und_section (sec)
1351 || bfd_is_com_section (sec))
1352 definition = false;
1353 else
1354 definition = true;
1356 size_change_ok = false;
1357 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1358 old_alignment = 0;
1359 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1361 Elf_Internal_Versym iver;
1362 unsigned int vernum = 0;
1363 boolean override;
1365 if (ever != NULL)
1367 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1368 vernum = iver.vs_vers & VERSYM_VERSION;
1370 /* If this is a hidden symbol, or if it is not version
1371 1, we append the version name to the symbol name.
1372 However, we do not modify a non-hidden absolute
1373 symbol, because it might be the version symbol
1374 itself. FIXME: What if it isn't? */
1375 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1376 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1378 const char *verstr;
1379 int namelen, newlen;
1380 char *newname, *p;
1382 if (sym.st_shndx != SHN_UNDEF)
1384 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1386 (*_bfd_error_handler)
1387 (_("%s: %s: invalid version %u (max %d)"),
1388 bfd_get_filename (abfd), name, vernum,
1389 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1390 bfd_set_error (bfd_error_bad_value);
1391 goto error_return;
1393 else if (vernum > 1)
1394 verstr =
1395 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1396 else
1397 verstr = "";
1399 else
1401 /* We cannot simply test for the number of
1402 entries in the VERNEED section since the
1403 numbers for the needed versions do not start
1404 at 0. */
1405 Elf_Internal_Verneed *t;
1407 verstr = NULL;
1408 for (t = elf_tdata (abfd)->verref;
1409 t != NULL;
1410 t = t->vn_nextref)
1412 Elf_Internal_Vernaux *a;
1414 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1416 if (a->vna_other == vernum)
1418 verstr = a->vna_nodename;
1419 break;
1422 if (a != NULL)
1423 break;
1425 if (verstr == NULL)
1427 (*_bfd_error_handler)
1428 (_("%s: %s: invalid needed version %d"),
1429 bfd_get_filename (abfd), name, vernum);
1430 bfd_set_error (bfd_error_bad_value);
1431 goto error_return;
1435 namelen = strlen (name);
1436 newlen = namelen + strlen (verstr) + 2;
1437 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1438 ++newlen;
1440 newname = (char *) bfd_alloc (abfd, newlen);
1441 if (newname == NULL)
1442 goto error_return;
1443 strcpy (newname, name);
1444 p = newname + namelen;
1445 *p++ = ELF_VER_CHR;
1446 /* If this is a defined non-hidden version symbol,
1447 we add another @ to the name. This indicates the
1448 default version of the symbol. */
1449 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1450 && sym.st_shndx != SHN_UNDEF)
1451 *p++ = ELF_VER_CHR;
1452 strcpy (p, verstr);
1454 name = newname;
1458 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1459 sym_hash, &override, &type_change_ok,
1460 &size_change_ok))
1461 goto error_return;
1463 if (override)
1464 definition = false;
1466 h = *sym_hash;
1467 while (h->root.type == bfd_link_hash_indirect
1468 || h->root.type == bfd_link_hash_warning)
1469 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1471 /* Remember the old alignment if this is a common symbol, so
1472 that we don't reduce the alignment later on. We can't
1473 check later, because _bfd_generic_link_add_one_symbol
1474 will set a default for the alignment which we want to
1475 override. */
1476 if (h->root.type == bfd_link_hash_common)
1477 old_alignment = h->root.u.c.p->alignment_power;
1479 if (elf_tdata (abfd)->verdef != NULL
1480 && ! override
1481 && vernum > 1
1482 && definition)
1483 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1486 if (! (_bfd_generic_link_add_one_symbol
1487 (info, abfd, name, flags, sec, value, (const char *) NULL,
1488 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1489 goto error_return;
1491 h = *sym_hash;
1492 while (h->root.type == bfd_link_hash_indirect
1493 || h->root.type == bfd_link_hash_warning)
1494 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1495 *sym_hash = h;
1497 new_weakdef = false;
1498 if (dynamic
1499 && definition
1500 && (flags & BSF_WEAK) != 0
1501 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1502 && info->hash->creator->flavour == bfd_target_elf_flavour
1503 && h->weakdef == NULL)
1505 /* Keep a list of all weak defined non function symbols from
1506 a dynamic object, using the weakdef field. Later in this
1507 function we will set the weakdef field to the correct
1508 value. We only put non-function symbols from dynamic
1509 objects on this list, because that happens to be the only
1510 time we need to know the normal symbol corresponding to a
1511 weak symbol, and the information is time consuming to
1512 figure out. If the weakdef field is not already NULL,
1513 then this symbol was already defined by some previous
1514 dynamic object, and we will be using that previous
1515 definition anyhow. */
1517 h->weakdef = weaks;
1518 weaks = h;
1519 new_weakdef = true;
1522 /* Set the alignment of a common symbol. */
1523 if (sym.st_shndx == SHN_COMMON
1524 && h->root.type == bfd_link_hash_common)
1526 unsigned int align;
1528 align = bfd_log2 (sym.st_value);
1529 if (align > old_alignment)
1530 h->root.u.c.p->alignment_power = align;
1533 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1535 int old_flags;
1536 boolean dynsym;
1537 int new_flag;
1539 /* Remember the symbol size and type. */
1540 if (sym.st_size != 0
1541 && (definition || h->size == 0))
1543 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1544 (*_bfd_error_handler)
1545 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1546 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1547 bfd_get_filename (abfd));
1549 h->size = sym.st_size;
1552 /* If this is a common symbol, then we always want H->SIZE
1553 to be the size of the common symbol. The code just above
1554 won't fix the size if a common symbol becomes larger. We
1555 don't warn about a size change here, because that is
1556 covered by --warn-common. */
1557 if (h->root.type == bfd_link_hash_common)
1558 h->size = h->root.u.c.size;
1560 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1561 && (definition || h->type == STT_NOTYPE))
1563 if (h->type != STT_NOTYPE
1564 && h->type != ELF_ST_TYPE (sym.st_info)
1565 && ! type_change_ok)
1566 (*_bfd_error_handler)
1567 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1568 name, h->type, ELF_ST_TYPE (sym.st_info),
1569 bfd_get_filename (abfd));
1571 h->type = ELF_ST_TYPE (sym.st_info);
1574 /* If st_other has a processor-specific meaning, specific code
1575 might be needed here. */
1576 if (sym.st_other != 0)
1578 /* Combine visibilities, using the most constraining one. */
1579 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1580 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1582 if (symvis && (hvis > symvis || hvis == 0))
1583 h->other = sym.st_other;
1585 /* If neither has visibility, use the st_other of the
1586 definition. This is an arbitrary choice, since the
1587 other bits have no general meaning. */
1588 if (!symvis && !hvis
1589 && (definition || h->other == 0))
1590 h->other = sym.st_other;
1593 /* Set a flag in the hash table entry indicating the type of
1594 reference or definition we just found. Keep a count of
1595 the number of dynamic symbols we find. A dynamic symbol
1596 is one which is referenced or defined by both a regular
1597 object and a shared object. */
1598 old_flags = h->elf_link_hash_flags;
1599 dynsym = false;
1600 if (! dynamic)
1602 if (! definition)
1604 new_flag = ELF_LINK_HASH_REF_REGULAR;
1605 if (bind != STB_WEAK)
1606 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1608 else
1609 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1610 if (info->shared
1611 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1612 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1613 dynsym = true;
1615 else
1617 if (! definition)
1618 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1619 else
1620 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1621 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1622 | ELF_LINK_HASH_REF_REGULAR)) != 0
1623 || (h->weakdef != NULL
1624 && ! new_weakdef
1625 && h->weakdef->dynindx != -1))
1626 dynsym = true;
1629 h->elf_link_hash_flags |= new_flag;
1631 /* If this symbol has a version, and it is the default
1632 version, we create an indirect symbol from the default
1633 name to the fully decorated name. This will cause
1634 external references which do not specify a version to be
1635 bound to this version of the symbol. */
1636 if (definition)
1638 char *p;
1640 p = strchr (name, ELF_VER_CHR);
1641 if (p != NULL && p[1] == ELF_VER_CHR)
1643 char *shortname;
1644 struct elf_link_hash_entry *hi;
1645 boolean override;
1647 shortname = bfd_hash_allocate (&info->hash->table,
1648 p - name + 1);
1649 if (shortname == NULL)
1650 goto error_return;
1651 strncpy (shortname, name, p - name);
1652 shortname[p - name] = '\0';
1654 /* We are going to create a new symbol. Merge it
1655 with any existing symbol with this name. For the
1656 purposes of the merge, act as though we were
1657 defining the symbol we just defined, although we
1658 actually going to define an indirect symbol. */
1659 type_change_ok = false;
1660 size_change_ok = false;
1661 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1662 &value, &hi, &override,
1663 &type_change_ok, &size_change_ok))
1664 goto error_return;
1666 if (! override)
1668 if (! (_bfd_generic_link_add_one_symbol
1669 (info, abfd, shortname, BSF_INDIRECT,
1670 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1671 collect, (struct bfd_link_hash_entry **) &hi)))
1672 goto error_return;
1674 else
1676 /* In this case the symbol named SHORTNAME is
1677 overriding the indirect symbol we want to
1678 add. We were planning on making SHORTNAME an
1679 indirect symbol referring to NAME. SHORTNAME
1680 is the name without a version. NAME is the
1681 fully versioned name, and it is the default
1682 version.
1684 Overriding means that we already saw a
1685 definition for the symbol SHORTNAME in a
1686 regular object, and it is overriding the
1687 symbol defined in the dynamic object.
1689 When this happens, we actually want to change
1690 NAME, the symbol we just added, to refer to
1691 SHORTNAME. This will cause references to
1692 NAME in the shared object to become
1693 references to SHORTNAME in the regular
1694 object. This is what we expect when we
1695 override a function in a shared object: that
1696 the references in the shared object will be
1697 mapped to the definition in the regular
1698 object. */
1700 while (hi->root.type == bfd_link_hash_indirect
1701 || hi->root.type == bfd_link_hash_warning)
1702 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1704 h->root.type = bfd_link_hash_indirect;
1705 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1706 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1708 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1709 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1710 if (hi->elf_link_hash_flags
1711 & (ELF_LINK_HASH_REF_REGULAR
1712 | ELF_LINK_HASH_DEF_REGULAR))
1714 if (! _bfd_elf_link_record_dynamic_symbol (info,
1715 hi))
1716 goto error_return;
1720 /* Now set HI to H, so that the following code
1721 will set the other fields correctly. */
1722 hi = h;
1725 /* If there is a duplicate definition somewhere,
1726 then HI may not point to an indirect symbol. We
1727 will have reported an error to the user in that
1728 case. */
1730 if (hi->root.type == bfd_link_hash_indirect)
1732 struct elf_link_hash_entry *ht;
1734 /* If the symbol became indirect, then we assume
1735 that we have not seen a definition before. */
1736 BFD_ASSERT ((hi->elf_link_hash_flags
1737 & (ELF_LINK_HASH_DEF_DYNAMIC
1738 | ELF_LINK_HASH_DEF_REGULAR))
1739 == 0);
1741 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1742 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1744 /* See if the new flags lead us to realize that
1745 the symbol must be dynamic. */
1746 if (! dynsym)
1748 if (! dynamic)
1750 if (info->shared
1751 || ((hi->elf_link_hash_flags
1752 & ELF_LINK_HASH_REF_DYNAMIC)
1753 != 0))
1754 dynsym = true;
1756 else
1758 if ((hi->elf_link_hash_flags
1759 & ELF_LINK_HASH_REF_REGULAR) != 0)
1760 dynsym = true;
1765 /* We also need to define an indirection from the
1766 nondefault version of the symbol. */
1768 shortname = bfd_hash_allocate (&info->hash->table,
1769 strlen (name));
1770 if (shortname == NULL)
1771 goto error_return;
1772 strncpy (shortname, name, p - name);
1773 strcpy (shortname + (p - name), p + 1);
1775 /* Once again, merge with any existing symbol. */
1776 type_change_ok = false;
1777 size_change_ok = false;
1778 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1779 &value, &hi, &override,
1780 &type_change_ok, &size_change_ok))
1781 goto error_return;
1783 if (override)
1785 /* Here SHORTNAME is a versioned name, so we
1786 don't expect to see the type of override we
1787 do in the case above. */
1788 (*_bfd_error_handler)
1789 (_("%s: warning: unexpected redefinition of `%s'"),
1790 bfd_get_filename (abfd), shortname);
1792 else
1794 if (! (_bfd_generic_link_add_one_symbol
1795 (info, abfd, shortname, BSF_INDIRECT,
1796 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1797 collect, (struct bfd_link_hash_entry **) &hi)))
1798 goto error_return;
1800 /* If there is a duplicate definition somewhere,
1801 then HI may not point to an indirect symbol.
1802 We will have reported an error to the user in
1803 that case. */
1805 if (hi->root.type == bfd_link_hash_indirect)
1807 /* If the symbol became indirect, then we
1808 assume that we have not seen a definition
1809 before. */
1810 BFD_ASSERT ((hi->elf_link_hash_flags
1811 & (ELF_LINK_HASH_DEF_DYNAMIC
1812 | ELF_LINK_HASH_DEF_REGULAR))
1813 == 0);
1815 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1817 /* See if the new flags lead us to realize
1818 that the symbol must be dynamic. */
1819 if (! dynsym)
1821 if (! dynamic)
1823 if (info->shared
1824 || ((hi->elf_link_hash_flags
1825 & ELF_LINK_HASH_REF_DYNAMIC)
1826 != 0))
1827 dynsym = true;
1829 else
1831 if ((hi->elf_link_hash_flags
1832 & ELF_LINK_HASH_REF_REGULAR) != 0)
1833 dynsym = true;
1841 if (dynsym && h->dynindx == -1)
1843 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1844 goto error_return;
1845 if (h->weakdef != NULL
1846 && ! new_weakdef
1847 && h->weakdef->dynindx == -1)
1849 if (! _bfd_elf_link_record_dynamic_symbol (info,
1850 h->weakdef))
1851 goto error_return;
1854 else if (dynsym && h->dynindx != -1)
1855 /* If the symbol already has a dynamic index, but
1856 visibility says it should not be visible, turn it into
1857 a local symbol. */
1858 switch (ELF_ST_VISIBILITY (h->other))
1860 case STV_INTERNAL:
1861 case STV_HIDDEN:
1862 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1863 (*bed->elf_backend_hide_symbol) (h);
1864 break;
1869 /* Now set the weakdefs field correctly for all the weak defined
1870 symbols we found. The only way to do this is to search all the
1871 symbols. Since we only need the information for non functions in
1872 dynamic objects, that's the only time we actually put anything on
1873 the list WEAKS. We need this information so that if a regular
1874 object refers to a symbol defined weakly in a dynamic object, the
1875 real symbol in the dynamic object is also put in the dynamic
1876 symbols; we also must arrange for both symbols to point to the
1877 same memory location. We could handle the general case of symbol
1878 aliasing, but a general symbol alias can only be generated in
1879 assembler code, handling it correctly would be very time
1880 consuming, and other ELF linkers don't handle general aliasing
1881 either. */
1882 while (weaks != NULL)
1884 struct elf_link_hash_entry *hlook;
1885 asection *slook;
1886 bfd_vma vlook;
1887 struct elf_link_hash_entry **hpp;
1888 struct elf_link_hash_entry **hppend;
1890 hlook = weaks;
1891 weaks = hlook->weakdef;
1892 hlook->weakdef = NULL;
1894 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1895 || hlook->root.type == bfd_link_hash_defweak
1896 || hlook->root.type == bfd_link_hash_common
1897 || hlook->root.type == bfd_link_hash_indirect);
1898 slook = hlook->root.u.def.section;
1899 vlook = hlook->root.u.def.value;
1901 hpp = elf_sym_hashes (abfd);
1902 hppend = hpp + extsymcount;
1903 for (; hpp < hppend; hpp++)
1905 struct elf_link_hash_entry *h;
1907 h = *hpp;
1908 if (h != NULL && h != hlook
1909 && h->root.type == bfd_link_hash_defined
1910 && h->root.u.def.section == slook
1911 && h->root.u.def.value == vlook)
1913 hlook->weakdef = h;
1915 /* If the weak definition is in the list of dynamic
1916 symbols, make sure the real definition is put there
1917 as well. */
1918 if (hlook->dynindx != -1
1919 && h->dynindx == -1)
1921 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1922 goto error_return;
1925 /* If the real definition is in the list of dynamic
1926 symbols, make sure the weak definition is put there
1927 as well. If we don't do this, then the dynamic
1928 loader might not merge the entries for the real
1929 definition and the weak definition. */
1930 if (h->dynindx != -1
1931 && hlook->dynindx == -1)
1933 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1934 goto error_return;
1937 break;
1942 if (buf != NULL)
1944 free (buf);
1945 buf = NULL;
1948 if (extversym != NULL)
1950 free (extversym);
1951 extversym = NULL;
1954 /* If this object is the same format as the output object, and it is
1955 not a shared library, then let the backend look through the
1956 relocs.
1958 This is required to build global offset table entries and to
1959 arrange for dynamic relocs. It is not required for the
1960 particular common case of linking non PIC code, even when linking
1961 against shared libraries, but unfortunately there is no way of
1962 knowing whether an object file has been compiled PIC or not.
1963 Looking through the relocs is not particularly time consuming.
1964 The problem is that we must either (1) keep the relocs in memory,
1965 which causes the linker to require additional runtime memory or
1966 (2) read the relocs twice from the input file, which wastes time.
1967 This would be a good case for using mmap.
1969 I have no idea how to handle linking PIC code into a file of a
1970 different format. It probably can't be done. */
1971 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1972 if (! dynamic
1973 && abfd->xvec == info->hash->creator
1974 && check_relocs != NULL)
1976 asection *o;
1978 for (o = abfd->sections; o != NULL; o = o->next)
1980 Elf_Internal_Rela *internal_relocs;
1981 boolean ok;
1983 if ((o->flags & SEC_RELOC) == 0
1984 || o->reloc_count == 0
1985 || ((info->strip == strip_all || info->strip == strip_debugger)
1986 && (o->flags & SEC_DEBUGGING) != 0)
1987 || bfd_is_abs_section (o->output_section))
1988 continue;
1990 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1991 (abfd, o, (PTR) NULL,
1992 (Elf_Internal_Rela *) NULL,
1993 info->keep_memory));
1994 if (internal_relocs == NULL)
1995 goto error_return;
1997 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1999 if (! info->keep_memory)
2000 free (internal_relocs);
2002 if (! ok)
2003 goto error_return;
2007 /* If this is a non-traditional, non-relocateable link, try to
2008 optimize the handling of the .stab/.stabstr sections. */
2009 if (! dynamic
2010 && ! info->relocateable
2011 && ! info->traditional_format
2012 && info->hash->creator->flavour == bfd_target_elf_flavour
2013 && (info->strip != strip_all && info->strip != strip_debugger))
2015 asection *stab, *stabstr;
2017 stab = bfd_get_section_by_name (abfd, ".stab");
2018 if (stab != NULL)
2020 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2022 if (stabstr != NULL)
2024 struct bfd_elf_section_data *secdata;
2026 secdata = elf_section_data (stab);
2027 if (! _bfd_link_section_stabs (abfd,
2028 &elf_hash_table (info)->stab_info,
2029 stab, stabstr,
2030 &secdata->stab_info))
2031 goto error_return;
2036 return true;
2038 error_return:
2039 if (buf != NULL)
2040 free (buf);
2041 if (dynbuf != NULL)
2042 free (dynbuf);
2043 if (dynver != NULL)
2044 free (dynver);
2045 if (extversym != NULL)
2046 free (extversym);
2047 return false;
2050 /* Create some sections which will be filled in with dynamic linking
2051 information. ABFD is an input file which requires dynamic sections
2052 to be created. The dynamic sections take up virtual memory space
2053 when the final executable is run, so we need to create them before
2054 addresses are assigned to the output sections. We work out the
2055 actual contents and size of these sections later. */
2057 boolean
2058 elf_link_create_dynamic_sections (abfd, info)
2059 bfd *abfd;
2060 struct bfd_link_info *info;
2062 flagword flags;
2063 register asection *s;
2064 struct elf_link_hash_entry *h;
2065 struct elf_backend_data *bed;
2067 if (elf_hash_table (info)->dynamic_sections_created)
2068 return true;
2070 /* Make sure that all dynamic sections use the same input BFD. */
2071 if (elf_hash_table (info)->dynobj == NULL)
2072 elf_hash_table (info)->dynobj = abfd;
2073 else
2074 abfd = elf_hash_table (info)->dynobj;
2076 /* Note that we set the SEC_IN_MEMORY flag for all of these
2077 sections. */
2078 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2079 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2081 /* A dynamically linked executable has a .interp section, but a
2082 shared library does not. */
2083 if (! info->shared)
2085 s = bfd_make_section (abfd, ".interp");
2086 if (s == NULL
2087 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2088 return false;
2091 /* Create sections to hold version informations. These are removed
2092 if they are not needed. */
2093 s = bfd_make_section (abfd, ".gnu.version_d");
2094 if (s == NULL
2095 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2096 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2097 return false;
2099 s = bfd_make_section (abfd, ".gnu.version");
2100 if (s == NULL
2101 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2102 || ! bfd_set_section_alignment (abfd, s, 1))
2103 return false;
2105 s = bfd_make_section (abfd, ".gnu.version_r");
2106 if (s == NULL
2107 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2108 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2109 return false;
2111 s = bfd_make_section (abfd, ".dynsym");
2112 if (s == NULL
2113 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2114 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2115 return false;
2117 s = bfd_make_section (abfd, ".dynstr");
2118 if (s == NULL
2119 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2120 return false;
2122 /* Create a strtab to hold the dynamic symbol names. */
2123 if (elf_hash_table (info)->dynstr == NULL)
2125 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2126 if (elf_hash_table (info)->dynstr == NULL)
2127 return false;
2130 s = bfd_make_section (abfd, ".dynamic");
2131 if (s == NULL
2132 || ! bfd_set_section_flags (abfd, s, flags)
2133 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2134 return false;
2136 /* The special symbol _DYNAMIC is always set to the start of the
2137 .dynamic section. This call occurs before we have processed the
2138 symbols for any dynamic object, so we don't have to worry about
2139 overriding a dynamic definition. We could set _DYNAMIC in a
2140 linker script, but we only want to define it if we are, in fact,
2141 creating a .dynamic section. We don't want to define it if there
2142 is no .dynamic section, since on some ELF platforms the start up
2143 code examines it to decide how to initialize the process. */
2144 h = NULL;
2145 if (! (_bfd_generic_link_add_one_symbol
2146 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2147 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2148 (struct bfd_link_hash_entry **) &h)))
2149 return false;
2150 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2151 h->type = STT_OBJECT;
2153 if (info->shared
2154 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2155 return false;
2157 bed = get_elf_backend_data (abfd);
2159 s = bfd_make_section (abfd, ".hash");
2160 if (s == NULL
2161 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2162 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2163 return false;
2164 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2166 /* Let the backend create the rest of the sections. This lets the
2167 backend set the right flags. The backend will normally create
2168 the .got and .plt sections. */
2169 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2170 return false;
2172 elf_hash_table (info)->dynamic_sections_created = true;
2174 return true;
2177 /* Add an entry to the .dynamic table. */
2179 boolean
2180 elf_add_dynamic_entry (info, tag, val)
2181 struct bfd_link_info *info;
2182 bfd_vma tag;
2183 bfd_vma val;
2185 Elf_Internal_Dyn dyn;
2186 bfd *dynobj;
2187 asection *s;
2188 size_t newsize;
2189 bfd_byte *newcontents;
2191 dynobj = elf_hash_table (info)->dynobj;
2193 s = bfd_get_section_by_name (dynobj, ".dynamic");
2194 BFD_ASSERT (s != NULL);
2196 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2197 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2198 if (newcontents == NULL)
2199 return false;
2201 dyn.d_tag = tag;
2202 dyn.d_un.d_val = val;
2203 elf_swap_dyn_out (dynobj, &dyn,
2204 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2206 s->_raw_size = newsize;
2207 s->contents = newcontents;
2209 return true;
2212 /* Record a new local dynamic symbol. */
2214 boolean
2215 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2216 struct bfd_link_info *info;
2217 bfd *input_bfd;
2218 long input_indx;
2220 struct elf_link_local_dynamic_entry *entry;
2221 struct elf_link_hash_table *eht;
2222 struct bfd_strtab_hash *dynstr;
2223 Elf_External_Sym esym;
2224 unsigned long dynstr_index;
2225 char *name;
2227 /* See if the entry exists already. */
2228 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2229 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2230 return true;
2232 entry = (struct elf_link_local_dynamic_entry *)
2233 bfd_alloc (input_bfd, sizeof (*entry));
2234 if (entry == NULL)
2235 return false;
2237 /* Go find the symbol, so that we can find it's name. */
2238 if (bfd_seek (input_bfd,
2239 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2240 + input_indx * sizeof (Elf_External_Sym)),
2241 SEEK_SET) != 0
2242 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2243 != sizeof (Elf_External_Sym)))
2244 return false;
2245 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2247 name = (bfd_elf_string_from_elf_section
2248 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2249 entry->isym.st_name));
2251 dynstr = elf_hash_table (info)->dynstr;
2252 if (dynstr == NULL)
2254 /* Create a strtab to hold the dynamic symbol names. */
2255 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2256 if (dynstr == NULL)
2257 return false;
2260 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2261 if (dynstr_index == (unsigned long) -1)
2262 return false;
2263 entry->isym.st_name = dynstr_index;
2265 eht = elf_hash_table (info);
2267 entry->next = eht->dynlocal;
2268 eht->dynlocal = entry;
2269 entry->input_bfd = input_bfd;
2270 entry->input_indx = input_indx;
2271 eht->dynsymcount++;
2273 /* Whatever binding the symbol had before, it's now local. */
2274 entry->isym.st_info
2275 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2277 /* The dynindx will be set at the end of size_dynamic_sections. */
2279 return true;
2283 /* Read and swap the relocs from the section indicated by SHDR. This
2284 may be either a REL or a RELA section. The relocations are
2285 translated into RELA relocations and stored in INTERNAL_RELOCS,
2286 which should have already been allocated to contain enough space.
2287 The EXTERNAL_RELOCS are a buffer where the external form of the
2288 relocations should be stored.
2290 Returns false if something goes wrong. */
2292 static boolean
2293 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2294 internal_relocs)
2295 bfd *abfd;
2296 Elf_Internal_Shdr *shdr;
2297 PTR external_relocs;
2298 Elf_Internal_Rela *internal_relocs;
2300 struct elf_backend_data *bed;
2302 /* If there aren't any relocations, that's OK. */
2303 if (!shdr)
2304 return true;
2306 /* Position ourselves at the start of the section. */
2307 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2308 return false;
2310 /* Read the relocations. */
2311 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2312 != shdr->sh_size)
2313 return false;
2315 bed = get_elf_backend_data (abfd);
2317 /* Convert the external relocations to the internal format. */
2318 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2320 Elf_External_Rel *erel;
2321 Elf_External_Rel *erelend;
2322 Elf_Internal_Rela *irela;
2323 Elf_Internal_Rel *irel;
2325 erel = (Elf_External_Rel *) external_relocs;
2326 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2327 irela = internal_relocs;
2328 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2329 * sizeof (Elf_Internal_Rel)));
2330 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2332 unsigned char i;
2334 if (bed->s->swap_reloc_in)
2335 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2336 else
2337 elf_swap_reloc_in (abfd, erel, irel);
2339 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2341 irela[i].r_offset = irel[i].r_offset;
2342 irela[i].r_info = irel[i].r_info;
2343 irela[i].r_addend = 0;
2347 else
2349 Elf_External_Rela *erela;
2350 Elf_External_Rela *erelaend;
2351 Elf_Internal_Rela *irela;
2353 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2355 erela = (Elf_External_Rela *) external_relocs;
2356 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2357 irela = internal_relocs;
2358 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2360 if (bed->s->swap_reloca_in)
2361 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2362 else
2363 elf_swap_reloca_in (abfd, erela, irela);
2367 return true;
2370 /* Read and swap the relocs for a section O. They may have been
2371 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2372 not NULL, they are used as buffers to read into. They are known to
2373 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2374 the return value is allocated using either malloc or bfd_alloc,
2375 according to the KEEP_MEMORY argument. If O has two relocation
2376 sections (both REL and RELA relocations), then the REL_HDR
2377 relocations will appear first in INTERNAL_RELOCS, followed by the
2378 REL_HDR2 relocations. */
2380 Elf_Internal_Rela *
2381 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2382 keep_memory)
2383 bfd *abfd;
2384 asection *o;
2385 PTR external_relocs;
2386 Elf_Internal_Rela *internal_relocs;
2387 boolean keep_memory;
2389 Elf_Internal_Shdr *rel_hdr;
2390 PTR alloc1 = NULL;
2391 Elf_Internal_Rela *alloc2 = NULL;
2392 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2394 if (elf_section_data (o)->relocs != NULL)
2395 return elf_section_data (o)->relocs;
2397 if (o->reloc_count == 0)
2398 return NULL;
2400 rel_hdr = &elf_section_data (o)->rel_hdr;
2402 if (internal_relocs == NULL)
2404 size_t size;
2406 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2407 * sizeof (Elf_Internal_Rela));
2408 if (keep_memory)
2409 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2410 else
2411 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2412 if (internal_relocs == NULL)
2413 goto error_return;
2416 if (external_relocs == NULL)
2418 size_t size = (size_t) rel_hdr->sh_size;
2420 if (elf_section_data (o)->rel_hdr2)
2421 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2422 alloc1 = (PTR) bfd_malloc (size);
2423 if (alloc1 == NULL)
2424 goto error_return;
2425 external_relocs = alloc1;
2428 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2429 external_relocs,
2430 internal_relocs))
2431 goto error_return;
2432 if (!elf_link_read_relocs_from_section
2433 (abfd,
2434 elf_section_data (o)->rel_hdr2,
2435 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2436 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2437 * bed->s->int_rels_per_ext_rel)))
2438 goto error_return;
2440 /* Cache the results for next time, if we can. */
2441 if (keep_memory)
2442 elf_section_data (o)->relocs = internal_relocs;
2444 if (alloc1 != NULL)
2445 free (alloc1);
2447 /* Don't free alloc2, since if it was allocated we are passing it
2448 back (under the name of internal_relocs). */
2450 return internal_relocs;
2452 error_return:
2453 if (alloc1 != NULL)
2454 free (alloc1);
2455 if (alloc2 != NULL)
2456 free (alloc2);
2457 return NULL;
2461 /* Record an assignment to a symbol made by a linker script. We need
2462 this in case some dynamic object refers to this symbol. */
2464 /*ARGSUSED*/
2465 boolean
2466 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2467 bfd *output_bfd ATTRIBUTE_UNUSED;
2468 struct bfd_link_info *info;
2469 const char *name;
2470 boolean provide;
2472 struct elf_link_hash_entry *h;
2474 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2475 return true;
2477 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2478 if (h == NULL)
2479 return false;
2481 if (h->root.type == bfd_link_hash_new)
2482 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2484 /* If this symbol is being provided by the linker script, and it is
2485 currently defined by a dynamic object, but not by a regular
2486 object, then mark it as undefined so that the generic linker will
2487 force the correct value. */
2488 if (provide
2489 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2490 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2491 h->root.type = bfd_link_hash_undefined;
2493 /* If this symbol is not being provided by the linker script, and it is
2494 currently defined by a dynamic object, but not by a regular object,
2495 then clear out any version information because the symbol will not be
2496 associated with the dynamic object any more. */
2497 if (!provide
2498 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2499 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2500 h->verinfo.verdef = NULL;
2502 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2504 /* When possible, keep the original type of the symbol */
2505 if (h->type == STT_NOTYPE)
2506 h->type = STT_OBJECT;
2508 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2509 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2510 || info->shared)
2511 && h->dynindx == -1)
2513 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2514 return false;
2516 /* If this is a weak defined symbol, and we know a corresponding
2517 real symbol from the same dynamic object, make sure the real
2518 symbol is also made into a dynamic symbol. */
2519 if (h->weakdef != NULL
2520 && h->weakdef->dynindx == -1)
2522 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2523 return false;
2527 return true;
2530 /* This structure is used to pass information to
2531 elf_link_assign_sym_version. */
2533 struct elf_assign_sym_version_info
2535 /* Output BFD. */
2536 bfd *output_bfd;
2537 /* General link information. */
2538 struct bfd_link_info *info;
2539 /* Version tree. */
2540 struct bfd_elf_version_tree *verdefs;
2541 /* Whether we are exporting all dynamic symbols. */
2542 boolean export_dynamic;
2543 /* Whether we had a failure. */
2544 boolean failed;
2547 /* This structure is used to pass information to
2548 elf_link_find_version_dependencies. */
2550 struct elf_find_verdep_info
2552 /* Output BFD. */
2553 bfd *output_bfd;
2554 /* General link information. */
2555 struct bfd_link_info *info;
2556 /* The number of dependencies. */
2557 unsigned int vers;
2558 /* Whether we had a failure. */
2559 boolean failed;
2562 /* Array used to determine the number of hash table buckets to use
2563 based on the number of symbols there are. If there are fewer than
2564 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2565 fewer than 37 we use 17 buckets, and so forth. We never use more
2566 than 32771 buckets. */
2568 static const size_t elf_buckets[] =
2570 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2571 16411, 32771, 0
2574 /* Compute bucket count for hashing table. We do not use a static set
2575 of possible tables sizes anymore. Instead we determine for all
2576 possible reasonable sizes of the table the outcome (i.e., the
2577 number of collisions etc) and choose the best solution. The
2578 weighting functions are not too simple to allow the table to grow
2579 without bounds. Instead one of the weighting factors is the size.
2580 Therefore the result is always a good payoff between few collisions
2581 (= short chain lengths) and table size. */
2582 static size_t
2583 compute_bucket_count (info)
2584 struct bfd_link_info *info;
2586 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2587 size_t best_size = 0;
2588 unsigned long int *hashcodes;
2589 unsigned long int *hashcodesp;
2590 unsigned long int i;
2592 /* Compute the hash values for all exported symbols. At the same
2593 time store the values in an array so that we could use them for
2594 optimizations. */
2595 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2596 * sizeof (unsigned long int));
2597 if (hashcodes == NULL)
2598 return 0;
2599 hashcodesp = hashcodes;
2601 /* Put all hash values in HASHCODES. */
2602 elf_link_hash_traverse (elf_hash_table (info),
2603 elf_collect_hash_codes, &hashcodesp);
2605 /* We have a problem here. The following code to optimize the table
2606 size requires an integer type with more the 32 bits. If
2607 BFD_HOST_U_64_BIT is set we know about such a type. */
2608 #ifdef BFD_HOST_U_64_BIT
2609 if (info->optimize == true)
2611 unsigned long int nsyms = hashcodesp - hashcodes;
2612 size_t minsize;
2613 size_t maxsize;
2614 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2615 unsigned long int *counts ;
2617 /* Possible optimization parameters: if we have NSYMS symbols we say
2618 that the hashing table must at least have NSYMS/4 and at most
2619 2*NSYMS buckets. */
2620 minsize = nsyms / 4;
2621 if (minsize == 0)
2622 minsize = 1;
2623 best_size = maxsize = nsyms * 2;
2625 /* Create array where we count the collisions in. We must use bfd_malloc
2626 since the size could be large. */
2627 counts = (unsigned long int *) bfd_malloc (maxsize
2628 * sizeof (unsigned long int));
2629 if (counts == NULL)
2631 free (hashcodes);
2632 return 0;
2635 /* Compute the "optimal" size for the hash table. The criteria is a
2636 minimal chain length. The minor criteria is (of course) the size
2637 of the table. */
2638 for (i = minsize; i < maxsize; ++i)
2640 /* Walk through the array of hashcodes and count the collisions. */
2641 BFD_HOST_U_64_BIT max;
2642 unsigned long int j;
2643 unsigned long int fact;
2645 memset (counts, '\0', i * sizeof (unsigned long int));
2647 /* Determine how often each hash bucket is used. */
2648 for (j = 0; j < nsyms; ++j)
2649 ++counts[hashcodes[j] % i];
2651 /* For the weight function we need some information about the
2652 pagesize on the target. This is information need not be 100%
2653 accurate. Since this information is not available (so far) we
2654 define it here to a reasonable default value. If it is crucial
2655 to have a better value some day simply define this value. */
2656 # ifndef BFD_TARGET_PAGESIZE
2657 # define BFD_TARGET_PAGESIZE (4096)
2658 # endif
2660 /* We in any case need 2 + NSYMS entries for the size values and
2661 the chains. */
2662 max = (2 + nsyms) * (ARCH_SIZE / 8);
2664 # if 1
2665 /* Variant 1: optimize for short chains. We add the squares
2666 of all the chain lengths (which favous many small chain
2667 over a few long chains). */
2668 for (j = 0; j < i; ++j)
2669 max += counts[j] * counts[j];
2671 /* This adds penalties for the overall size of the table. */
2672 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2673 max *= fact * fact;
2674 # else
2675 /* Variant 2: Optimize a lot more for small table. Here we
2676 also add squares of the size but we also add penalties for
2677 empty slots (the +1 term). */
2678 for (j = 0; j < i; ++j)
2679 max += (1 + counts[j]) * (1 + counts[j]);
2681 /* The overall size of the table is considered, but not as
2682 strong as in variant 1, where it is squared. */
2683 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2684 max *= fact;
2685 # endif
2687 /* Compare with current best results. */
2688 if (max < best_chlen)
2690 best_chlen = max;
2691 best_size = i;
2695 free (counts);
2697 else
2698 #endif /* defined (BFD_HOST_U_64_BIT) */
2700 /* This is the fallback solution if no 64bit type is available or if we
2701 are not supposed to spend much time on optimizations. We select the
2702 bucket count using a fixed set of numbers. */
2703 for (i = 0; elf_buckets[i] != 0; i++)
2705 best_size = elf_buckets[i];
2706 if (dynsymcount < elf_buckets[i + 1])
2707 break;
2711 /* Free the arrays we needed. */
2712 free (hashcodes);
2714 return best_size;
2717 /* Set up the sizes and contents of the ELF dynamic sections. This is
2718 called by the ELF linker emulation before_allocation routine. We
2719 must set the sizes of the sections before the linker sets the
2720 addresses of the various sections. */
2722 boolean
2723 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2724 export_dynamic, filter_shlib,
2725 auxiliary_filters, info, sinterpptr,
2726 verdefs)
2727 bfd *output_bfd;
2728 const char *soname;
2729 const char *rpath;
2730 boolean export_dynamic;
2731 const char *filter_shlib;
2732 const char * const *auxiliary_filters;
2733 struct bfd_link_info *info;
2734 asection **sinterpptr;
2735 struct bfd_elf_version_tree *verdefs;
2737 bfd_size_type soname_indx;
2738 bfd *dynobj;
2739 struct elf_backend_data *bed;
2740 struct elf_assign_sym_version_info asvinfo;
2742 *sinterpptr = NULL;
2744 soname_indx = (bfd_size_type) -1;
2746 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2747 return true;
2749 /* The backend may have to create some sections regardless of whether
2750 we're dynamic or not. */
2751 bed = get_elf_backend_data (output_bfd);
2752 if (bed->elf_backend_always_size_sections
2753 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2754 return false;
2756 dynobj = elf_hash_table (info)->dynobj;
2758 /* If there were no dynamic objects in the link, there is nothing to
2759 do here. */
2760 if (dynobj == NULL)
2761 return true;
2763 if (elf_hash_table (info)->dynamic_sections_created)
2765 struct elf_info_failed eif;
2766 struct elf_link_hash_entry *h;
2767 bfd_size_type strsize;
2769 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2770 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2772 if (soname != NULL)
2774 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2775 soname, true, true);
2776 if (soname_indx == (bfd_size_type) -1
2777 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2778 return false;
2781 if (info->symbolic)
2783 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2784 return false;
2787 if (rpath != NULL)
2789 bfd_size_type indx;
2791 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2792 true, true);
2793 if (indx == (bfd_size_type) -1
2794 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2795 return false;
2798 if (filter_shlib != NULL)
2800 bfd_size_type indx;
2802 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2803 filter_shlib, true, true);
2804 if (indx == (bfd_size_type) -1
2805 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2806 return false;
2809 if (auxiliary_filters != NULL)
2811 const char * const *p;
2813 for (p = auxiliary_filters; *p != NULL; p++)
2815 bfd_size_type indx;
2817 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2818 *p, true, true);
2819 if (indx == (bfd_size_type) -1
2820 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2821 return false;
2825 /* If we are supposed to export all symbols into the dynamic symbol
2826 table (this is not the normal case), then do so. */
2827 if (export_dynamic)
2829 struct elf_info_failed eif;
2831 eif.failed = false;
2832 eif.info = info;
2833 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2834 (PTR) &eif);
2835 if (eif.failed)
2836 return false;
2839 /* Attach all the symbols to their version information. */
2840 asvinfo.output_bfd = output_bfd;
2841 asvinfo.info = info;
2842 asvinfo.verdefs = verdefs;
2843 asvinfo.export_dynamic = export_dynamic;
2844 asvinfo.failed = false;
2846 elf_link_hash_traverse (elf_hash_table (info),
2847 elf_link_assign_sym_version,
2848 (PTR) &asvinfo);
2849 if (asvinfo.failed)
2850 return false;
2852 /* Find all symbols which were defined in a dynamic object and make
2853 the backend pick a reasonable value for them. */
2854 eif.failed = false;
2855 eif.info = info;
2856 elf_link_hash_traverse (elf_hash_table (info),
2857 elf_adjust_dynamic_symbol,
2858 (PTR) &eif);
2859 if (eif.failed)
2860 return false;
2862 /* Add some entries to the .dynamic section. We fill in some of the
2863 values later, in elf_bfd_final_link, but we must add the entries
2864 now so that we know the final size of the .dynamic section. */
2866 /* If there are initialization and/or finalization functions to
2867 call then add the corresponding DT_INIT/DT_FINI entries. */
2868 h = (info->init_function
2869 ? elf_link_hash_lookup (elf_hash_table (info),
2870 info->init_function, false,
2871 false, false)
2872 : NULL);
2873 if (h != NULL
2874 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2875 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2877 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2878 return false;
2880 h = (info->fini_function
2881 ? elf_link_hash_lookup (elf_hash_table (info),
2882 info->fini_function, false,
2883 false, false)
2884 : NULL);
2885 if (h != NULL
2886 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2887 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2889 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2890 return false;
2893 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2894 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2895 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2896 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2897 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2898 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2899 sizeof (Elf_External_Sym)))
2900 return false;
2903 /* The backend must work out the sizes of all the other dynamic
2904 sections. */
2905 if (bed->elf_backend_size_dynamic_sections
2906 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2907 return false;
2909 if (elf_hash_table (info)->dynamic_sections_created)
2911 size_t dynsymcount;
2912 asection *s;
2913 size_t bucketcount = 0;
2914 Elf_Internal_Sym isym;
2915 size_t hash_entry_size;
2917 /* Set up the version definition section. */
2918 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2919 BFD_ASSERT (s != NULL);
2921 /* We may have created additional version definitions if we are
2922 just linking a regular application. */
2923 verdefs = asvinfo.verdefs;
2925 if (verdefs == NULL)
2926 _bfd_strip_section_from_output (info, s);
2927 else
2929 unsigned int cdefs;
2930 bfd_size_type size;
2931 struct bfd_elf_version_tree *t;
2932 bfd_byte *p;
2933 Elf_Internal_Verdef def;
2934 Elf_Internal_Verdaux defaux;
2936 cdefs = 0;
2937 size = 0;
2939 /* Make space for the base version. */
2940 size += sizeof (Elf_External_Verdef);
2941 size += sizeof (Elf_External_Verdaux);
2942 ++cdefs;
2944 for (t = verdefs; t != NULL; t = t->next)
2946 struct bfd_elf_version_deps *n;
2948 size += sizeof (Elf_External_Verdef);
2949 size += sizeof (Elf_External_Verdaux);
2950 ++cdefs;
2952 for (n = t->deps; n != NULL; n = n->next)
2953 size += sizeof (Elf_External_Verdaux);
2956 s->_raw_size = size;
2957 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2958 if (s->contents == NULL && s->_raw_size != 0)
2959 return false;
2961 /* Fill in the version definition section. */
2963 p = s->contents;
2965 def.vd_version = VER_DEF_CURRENT;
2966 def.vd_flags = VER_FLG_BASE;
2967 def.vd_ndx = 1;
2968 def.vd_cnt = 1;
2969 def.vd_aux = sizeof (Elf_External_Verdef);
2970 def.vd_next = (sizeof (Elf_External_Verdef)
2971 + sizeof (Elf_External_Verdaux));
2973 if (soname_indx != (bfd_size_type) -1)
2975 def.vd_hash = bfd_elf_hash (soname);
2976 defaux.vda_name = soname_indx;
2978 else
2980 const char *name;
2981 bfd_size_type indx;
2983 name = output_bfd->filename;
2984 def.vd_hash = bfd_elf_hash (name);
2985 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2986 name, true, false);
2987 if (indx == (bfd_size_type) -1)
2988 return false;
2989 defaux.vda_name = indx;
2991 defaux.vda_next = 0;
2993 _bfd_elf_swap_verdef_out (output_bfd, &def,
2994 (Elf_External_Verdef *)p);
2995 p += sizeof (Elf_External_Verdef);
2996 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2997 (Elf_External_Verdaux *) p);
2998 p += sizeof (Elf_External_Verdaux);
3000 for (t = verdefs; t != NULL; t = t->next)
3002 unsigned int cdeps;
3003 struct bfd_elf_version_deps *n;
3004 struct elf_link_hash_entry *h;
3006 cdeps = 0;
3007 for (n = t->deps; n != NULL; n = n->next)
3008 ++cdeps;
3010 /* Add a symbol representing this version. */
3011 h = NULL;
3012 if (! (_bfd_generic_link_add_one_symbol
3013 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3014 (bfd_vma) 0, (const char *) NULL, false,
3015 get_elf_backend_data (dynobj)->collect,
3016 (struct bfd_link_hash_entry **) &h)))
3017 return false;
3018 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3019 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3020 h->type = STT_OBJECT;
3021 h->verinfo.vertree = t;
3023 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3024 return false;
3026 def.vd_version = VER_DEF_CURRENT;
3027 def.vd_flags = 0;
3028 if (t->globals == NULL && t->locals == NULL && ! t->used)
3029 def.vd_flags |= VER_FLG_WEAK;
3030 def.vd_ndx = t->vernum + 1;
3031 def.vd_cnt = cdeps + 1;
3032 def.vd_hash = bfd_elf_hash (t->name);
3033 def.vd_aux = sizeof (Elf_External_Verdef);
3034 if (t->next != NULL)
3035 def.vd_next = (sizeof (Elf_External_Verdef)
3036 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3037 else
3038 def.vd_next = 0;
3040 _bfd_elf_swap_verdef_out (output_bfd, &def,
3041 (Elf_External_Verdef *) p);
3042 p += sizeof (Elf_External_Verdef);
3044 defaux.vda_name = h->dynstr_index;
3045 if (t->deps == NULL)
3046 defaux.vda_next = 0;
3047 else
3048 defaux.vda_next = sizeof (Elf_External_Verdaux);
3049 t->name_indx = defaux.vda_name;
3051 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3052 (Elf_External_Verdaux *) p);
3053 p += sizeof (Elf_External_Verdaux);
3055 for (n = t->deps; n != NULL; n = n->next)
3057 if (n->version_needed == NULL)
3059 /* This can happen if there was an error in the
3060 version script. */
3061 defaux.vda_name = 0;
3063 else
3064 defaux.vda_name = n->version_needed->name_indx;
3065 if (n->next == NULL)
3066 defaux.vda_next = 0;
3067 else
3068 defaux.vda_next = sizeof (Elf_External_Verdaux);
3070 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3071 (Elf_External_Verdaux *) p);
3072 p += sizeof (Elf_External_Verdaux);
3076 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3077 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3078 return false;
3080 elf_tdata (output_bfd)->cverdefs = cdefs;
3083 /* Work out the size of the version reference section. */
3085 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3086 BFD_ASSERT (s != NULL);
3088 struct elf_find_verdep_info sinfo;
3090 sinfo.output_bfd = output_bfd;
3091 sinfo.info = info;
3092 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3093 if (sinfo.vers == 0)
3094 sinfo.vers = 1;
3095 sinfo.failed = false;
3097 elf_link_hash_traverse (elf_hash_table (info),
3098 elf_link_find_version_dependencies,
3099 (PTR) &sinfo);
3101 if (elf_tdata (output_bfd)->verref == NULL)
3102 _bfd_strip_section_from_output (info, s);
3103 else
3105 Elf_Internal_Verneed *t;
3106 unsigned int size;
3107 unsigned int crefs;
3108 bfd_byte *p;
3110 /* Build the version definition section. */
3111 size = 0;
3112 crefs = 0;
3113 for (t = elf_tdata (output_bfd)->verref;
3114 t != NULL;
3115 t = t->vn_nextref)
3117 Elf_Internal_Vernaux *a;
3119 size += sizeof (Elf_External_Verneed);
3120 ++crefs;
3121 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3122 size += sizeof (Elf_External_Vernaux);
3125 s->_raw_size = size;
3126 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3127 if (s->contents == NULL)
3128 return false;
3130 p = s->contents;
3131 for (t = elf_tdata (output_bfd)->verref;
3132 t != NULL;
3133 t = t->vn_nextref)
3135 unsigned int caux;
3136 Elf_Internal_Vernaux *a;
3137 bfd_size_type indx;
3139 caux = 0;
3140 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3141 ++caux;
3143 t->vn_version = VER_NEED_CURRENT;
3144 t->vn_cnt = caux;
3145 if (elf_dt_name (t->vn_bfd) != NULL)
3146 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3147 elf_dt_name (t->vn_bfd),
3148 true, false);
3149 else
3150 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3151 t->vn_bfd->filename, true, false);
3152 if (indx == (bfd_size_type) -1)
3153 return false;
3154 t->vn_file = indx;
3155 t->vn_aux = sizeof (Elf_External_Verneed);
3156 if (t->vn_nextref == NULL)
3157 t->vn_next = 0;
3158 else
3159 t->vn_next = (sizeof (Elf_External_Verneed)
3160 + caux * sizeof (Elf_External_Vernaux));
3162 _bfd_elf_swap_verneed_out (output_bfd, t,
3163 (Elf_External_Verneed *) p);
3164 p += sizeof (Elf_External_Verneed);
3166 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3168 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3169 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3170 a->vna_nodename, true, false);
3171 if (indx == (bfd_size_type) -1)
3172 return false;
3173 a->vna_name = indx;
3174 if (a->vna_nextptr == NULL)
3175 a->vna_next = 0;
3176 else
3177 a->vna_next = sizeof (Elf_External_Vernaux);
3179 _bfd_elf_swap_vernaux_out (output_bfd, a,
3180 (Elf_External_Vernaux *) p);
3181 p += sizeof (Elf_External_Vernaux);
3185 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3186 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3187 return false;
3189 elf_tdata (output_bfd)->cverrefs = crefs;
3193 /* Assign dynsym indicies. In a shared library we generate a
3194 section symbol for each output section, which come first.
3195 Next come all of the back-end allocated local dynamic syms,
3196 followed by the rest of the global symbols. */
3198 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3200 /* Work out the size of the symbol version section. */
3201 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3202 BFD_ASSERT (s != NULL);
3203 if (dynsymcount == 0
3204 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3206 _bfd_strip_section_from_output (info, s);
3207 /* The DYNSYMCOUNT might have changed if we were going to
3208 output a dynamic symbol table entry for S. */
3209 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3211 else
3213 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3214 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3215 if (s->contents == NULL)
3216 return false;
3218 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3219 return false;
3222 /* Set the size of the .dynsym and .hash sections. We counted
3223 the number of dynamic symbols in elf_link_add_object_symbols.
3224 We will build the contents of .dynsym and .hash when we build
3225 the final symbol table, because until then we do not know the
3226 correct value to give the symbols. We built the .dynstr
3227 section as we went along in elf_link_add_object_symbols. */
3228 s = bfd_get_section_by_name (dynobj, ".dynsym");
3229 BFD_ASSERT (s != NULL);
3230 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3231 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3232 if (s->contents == NULL && s->_raw_size != 0)
3233 return false;
3235 /* The first entry in .dynsym is a dummy symbol. */
3236 isym.st_value = 0;
3237 isym.st_size = 0;
3238 isym.st_name = 0;
3239 isym.st_info = 0;
3240 isym.st_other = 0;
3241 isym.st_shndx = 0;
3242 elf_swap_symbol_out (output_bfd, &isym,
3243 (PTR) (Elf_External_Sym *) s->contents);
3245 /* Compute the size of the hashing table. As a side effect this
3246 computes the hash values for all the names we export. */
3247 bucketcount = compute_bucket_count (info);
3249 s = bfd_get_section_by_name (dynobj, ".hash");
3250 BFD_ASSERT (s != NULL);
3251 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3252 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3253 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3254 if (s->contents == NULL)
3255 return false;
3256 memset (s->contents, 0, (size_t) s->_raw_size);
3258 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3259 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3260 s->contents + hash_entry_size);
3262 elf_hash_table (info)->bucketcount = bucketcount;
3264 s = bfd_get_section_by_name (dynobj, ".dynstr");
3265 BFD_ASSERT (s != NULL);
3266 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3268 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3269 return false;
3272 return true;
3275 /* Fix up the flags for a symbol. This handles various cases which
3276 can only be fixed after all the input files are seen. This is
3277 currently called by both adjust_dynamic_symbol and
3278 assign_sym_version, which is unnecessary but perhaps more robust in
3279 the face of future changes. */
3281 static boolean
3282 elf_fix_symbol_flags (h, eif)
3283 struct elf_link_hash_entry *h;
3284 struct elf_info_failed *eif;
3286 /* If this symbol was mentioned in a non-ELF file, try to set
3287 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3288 permit a non-ELF file to correctly refer to a symbol defined in
3289 an ELF dynamic object. */
3290 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3292 if (h->root.type != bfd_link_hash_defined
3293 && h->root.type != bfd_link_hash_defweak)
3294 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3295 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3296 else
3298 if (h->root.u.def.section->owner != NULL
3299 && (bfd_get_flavour (h->root.u.def.section->owner)
3300 == bfd_target_elf_flavour))
3301 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3302 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3303 else
3304 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3307 if (h->dynindx == -1
3308 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3309 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3311 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3313 eif->failed = true;
3314 return false;
3318 else
3320 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3321 was first seen in a non-ELF file. Fortunately, if the symbol
3322 was first seen in an ELF file, we're probably OK unless the
3323 symbol was defined in a non-ELF file. Catch that case here.
3324 FIXME: We're still in trouble if the symbol was first seen in
3325 a dynamic object, and then later in a non-ELF regular object. */
3326 if ((h->root.type == bfd_link_hash_defined
3327 || h->root.type == bfd_link_hash_defweak)
3328 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3329 && (h->root.u.def.section->owner != NULL
3330 ? (bfd_get_flavour (h->root.u.def.section->owner)
3331 != bfd_target_elf_flavour)
3332 : (bfd_is_abs_section (h->root.u.def.section)
3333 && (h->elf_link_hash_flags
3334 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3335 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3338 /* If this is a final link, and the symbol was defined as a common
3339 symbol in a regular object file, and there was no definition in
3340 any dynamic object, then the linker will have allocated space for
3341 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3342 flag will not have been set. */
3343 if (h->root.type == bfd_link_hash_defined
3344 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3345 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3346 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3347 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3348 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3350 /* If -Bsymbolic was used (which means to bind references to global
3351 symbols to the definition within the shared object), and this
3352 symbol was defined in a regular object, then it actually doesn't
3353 need a PLT entry. Likewise, if the symbol has any kind of
3354 visibility (internal, hidden, or protected), it doesn't need a
3355 PLT. */
3356 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3357 && eif->info->shared
3358 && (eif->info->symbolic || ELF_ST_VISIBILITY (h->other))
3359 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3361 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3362 h->plt.offset = (bfd_vma) -1;
3365 /* If this is a weak defined symbol in a dynamic object, and we know
3366 the real definition in the dynamic object, copy interesting flags
3367 over to the real definition. */
3368 if (h->weakdef != NULL)
3370 struct elf_link_hash_entry *weakdef;
3372 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3373 || h->root.type == bfd_link_hash_defweak);
3374 weakdef = h->weakdef;
3375 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3376 || weakdef->root.type == bfd_link_hash_defweak);
3377 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3379 /* If the real definition is defined by a regular object file,
3380 don't do anything special. See the longer description in
3381 elf_adjust_dynamic_symbol, below. */
3382 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3383 h->weakdef = NULL;
3384 else
3385 weakdef->elf_link_hash_flags |=
3386 (h->elf_link_hash_flags
3387 & (ELF_LINK_HASH_REF_REGULAR
3388 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3389 | ELF_LINK_NON_GOT_REF));
3392 return true;
3395 /* Make the backend pick a good value for a dynamic symbol. This is
3396 called via elf_link_hash_traverse, and also calls itself
3397 recursively. */
3399 static boolean
3400 elf_adjust_dynamic_symbol (h, data)
3401 struct elf_link_hash_entry *h;
3402 PTR data;
3404 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3405 bfd *dynobj;
3406 struct elf_backend_data *bed;
3408 /* Ignore indirect symbols. These are added by the versioning code. */
3409 if (h->root.type == bfd_link_hash_indirect)
3410 return true;
3412 /* Fix the symbol flags. */
3413 if (! elf_fix_symbol_flags (h, eif))
3414 return false;
3416 /* If this symbol does not require a PLT entry, and it is not
3417 defined by a dynamic object, or is not referenced by a regular
3418 object, ignore it. We do have to handle a weak defined symbol,
3419 even if no regular object refers to it, if we decided to add it
3420 to the dynamic symbol table. FIXME: Do we normally need to worry
3421 about symbols which are defined by one dynamic object and
3422 referenced by another one? */
3423 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3424 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3425 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3426 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3427 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3429 h->plt.offset = (bfd_vma) -1;
3430 return true;
3433 /* If we've already adjusted this symbol, don't do it again. This
3434 can happen via a recursive call. */
3435 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3436 return true;
3438 /* Don't look at this symbol again. Note that we must set this
3439 after checking the above conditions, because we may look at a
3440 symbol once, decide not to do anything, and then get called
3441 recursively later after REF_REGULAR is set below. */
3442 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3444 /* If this is a weak definition, and we know a real definition, and
3445 the real symbol is not itself defined by a regular object file,
3446 then get a good value for the real definition. We handle the
3447 real symbol first, for the convenience of the backend routine.
3449 Note that there is a confusing case here. If the real definition
3450 is defined by a regular object file, we don't get the real symbol
3451 from the dynamic object, but we do get the weak symbol. If the
3452 processor backend uses a COPY reloc, then if some routine in the
3453 dynamic object changes the real symbol, we will not see that
3454 change in the corresponding weak symbol. This is the way other
3455 ELF linkers work as well, and seems to be a result of the shared
3456 library model.
3458 I will clarify this issue. Most SVR4 shared libraries define the
3459 variable _timezone and define timezone as a weak synonym. The
3460 tzset call changes _timezone. If you write
3461 extern int timezone;
3462 int _timezone = 5;
3463 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3464 you might expect that, since timezone is a synonym for _timezone,
3465 the same number will print both times. However, if the processor
3466 backend uses a COPY reloc, then actually timezone will be copied
3467 into your process image, and, since you define _timezone
3468 yourself, _timezone will not. Thus timezone and _timezone will
3469 wind up at different memory locations. The tzset call will set
3470 _timezone, leaving timezone unchanged. */
3472 if (h->weakdef != NULL)
3474 /* If we get to this point, we know there is an implicit
3475 reference by a regular object file via the weak symbol H.
3476 FIXME: Is this really true? What if the traversal finds
3477 H->WEAKDEF before it finds H? */
3478 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3480 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3481 return false;
3484 /* If a symbol has no type and no size and does not require a PLT
3485 entry, then we are probably about to do the wrong thing here: we
3486 are probably going to create a COPY reloc for an empty object.
3487 This case can arise when a shared object is built with assembly
3488 code, and the assembly code fails to set the symbol type. */
3489 if (h->size == 0
3490 && h->type == STT_NOTYPE
3491 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3492 (*_bfd_error_handler)
3493 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3494 h->root.root.string);
3496 dynobj = elf_hash_table (eif->info)->dynobj;
3497 bed = get_elf_backend_data (dynobj);
3498 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3500 eif->failed = true;
3501 return false;
3504 return true;
3507 /* This routine is used to export all defined symbols into the dynamic
3508 symbol table. It is called via elf_link_hash_traverse. */
3510 static boolean
3511 elf_export_symbol (h, data)
3512 struct elf_link_hash_entry *h;
3513 PTR data;
3515 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3517 /* Ignore indirect symbols. These are added by the versioning code. */
3518 if (h->root.type == bfd_link_hash_indirect)
3519 return true;
3521 if (h->dynindx == -1
3522 && (h->elf_link_hash_flags
3523 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3525 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3527 eif->failed = true;
3528 return false;
3532 return true;
3535 /* Look through the symbols which are defined in other shared
3536 libraries and referenced here. Update the list of version
3537 dependencies. This will be put into the .gnu.version_r section.
3538 This function is called via elf_link_hash_traverse. */
3540 static boolean
3541 elf_link_find_version_dependencies (h, data)
3542 struct elf_link_hash_entry *h;
3543 PTR data;
3545 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3546 Elf_Internal_Verneed *t;
3547 Elf_Internal_Vernaux *a;
3549 /* We only care about symbols defined in shared objects with version
3550 information. */
3551 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3552 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3553 || h->dynindx == -1
3554 || h->verinfo.verdef == NULL)
3555 return true;
3557 /* See if we already know about this version. */
3558 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3560 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3561 continue;
3563 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3564 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3565 return true;
3567 break;
3570 /* This is a new version. Add it to tree we are building. */
3572 if (t == NULL)
3574 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3575 if (t == NULL)
3577 rinfo->failed = true;
3578 return false;
3581 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3582 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3583 elf_tdata (rinfo->output_bfd)->verref = t;
3586 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3588 /* Note that we are copying a string pointer here, and testing it
3589 above. If bfd_elf_string_from_elf_section is ever changed to
3590 discard the string data when low in memory, this will have to be
3591 fixed. */
3592 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3594 a->vna_flags = h->verinfo.verdef->vd_flags;
3595 a->vna_nextptr = t->vn_auxptr;
3597 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3598 ++rinfo->vers;
3600 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3602 t->vn_auxptr = a;
3604 return true;
3607 /* Figure out appropriate versions for all the symbols. We may not
3608 have the version number script until we have read all of the input
3609 files, so until that point we don't know which symbols should be
3610 local. This function is called via elf_link_hash_traverse. */
3612 static boolean
3613 elf_link_assign_sym_version (h, data)
3614 struct elf_link_hash_entry *h;
3615 PTR data;
3617 struct elf_assign_sym_version_info *sinfo =
3618 (struct elf_assign_sym_version_info *) data;
3619 struct bfd_link_info *info = sinfo->info;
3620 struct elf_backend_data *bed;
3621 struct elf_info_failed eif;
3622 char *p;
3624 /* Fix the symbol flags. */
3625 eif.failed = false;
3626 eif.info = info;
3627 if (! elf_fix_symbol_flags (h, &eif))
3629 if (eif.failed)
3630 sinfo->failed = true;
3631 return false;
3634 /* We only need version numbers for symbols defined in regular
3635 objects. */
3636 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3637 return true;
3639 bed = get_elf_backend_data (sinfo->output_bfd);
3640 p = strchr (h->root.root.string, ELF_VER_CHR);
3641 if (p != NULL && h->verinfo.vertree == NULL)
3643 struct bfd_elf_version_tree *t;
3644 boolean hidden;
3646 hidden = true;
3648 /* There are two consecutive ELF_VER_CHR characters if this is
3649 not a hidden symbol. */
3650 ++p;
3651 if (*p == ELF_VER_CHR)
3653 hidden = false;
3654 ++p;
3657 /* If there is no version string, we can just return out. */
3658 if (*p == '\0')
3660 if (hidden)
3661 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3662 return true;
3665 /* Look for the version. If we find it, it is no longer weak. */
3666 for (t = sinfo->verdefs; t != NULL; t = t->next)
3668 if (strcmp (t->name, p) == 0)
3670 int len;
3671 char *alc;
3672 struct bfd_elf_version_expr *d;
3674 len = p - h->root.root.string;
3675 alc = bfd_alloc (sinfo->output_bfd, len);
3676 if (alc == NULL)
3677 return false;
3678 strncpy (alc, h->root.root.string, len - 1);
3679 alc[len - 1] = '\0';
3680 if (alc[len - 2] == ELF_VER_CHR)
3681 alc[len - 2] = '\0';
3683 h->verinfo.vertree = t;
3684 t->used = true;
3685 d = NULL;
3687 if (t->globals != NULL)
3689 for (d = t->globals; d != NULL; d = d->next)
3690 if ((*d->match) (d, alc))
3691 break;
3694 /* See if there is anything to force this symbol to
3695 local scope. */
3696 if (d == NULL && t->locals != NULL)
3698 for (d = t->locals; d != NULL; d = d->next)
3700 if ((*d->match) (d, alc))
3702 if (h->dynindx != -1
3703 && info->shared
3704 && ! sinfo->export_dynamic)
3706 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3707 (*bed->elf_backend_hide_symbol) (h);
3708 /* FIXME: The name of the symbol has
3709 already been recorded in the dynamic
3710 string table section. */
3713 break;
3718 bfd_release (sinfo->output_bfd, alc);
3719 break;
3723 /* If we are building an application, we need to create a
3724 version node for this version. */
3725 if (t == NULL && ! info->shared)
3727 struct bfd_elf_version_tree **pp;
3728 int version_index;
3730 /* If we aren't going to export this symbol, we don't need
3731 to worry about it. */
3732 if (h->dynindx == -1)
3733 return true;
3735 t = ((struct bfd_elf_version_tree *)
3736 bfd_alloc (sinfo->output_bfd, sizeof *t));
3737 if (t == NULL)
3739 sinfo->failed = true;
3740 return false;
3743 t->next = NULL;
3744 t->name = p;
3745 t->globals = NULL;
3746 t->locals = NULL;
3747 t->deps = NULL;
3748 t->name_indx = (unsigned int) -1;
3749 t->used = true;
3751 version_index = 1;
3752 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3753 ++version_index;
3754 t->vernum = version_index;
3756 *pp = t;
3758 h->verinfo.vertree = t;
3760 else if (t == NULL)
3762 /* We could not find the version for a symbol when
3763 generating a shared archive. Return an error. */
3764 (*_bfd_error_handler)
3765 (_("%s: undefined versioned symbol name %s"),
3766 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3767 bfd_set_error (bfd_error_bad_value);
3768 sinfo->failed = true;
3769 return false;
3772 if (hidden)
3773 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3776 /* If we don't have a version for this symbol, see if we can find
3777 something. */
3778 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3780 struct bfd_elf_version_tree *t;
3781 struct bfd_elf_version_tree *deflt;
3782 struct bfd_elf_version_expr *d;
3784 /* See if can find what version this symbol is in. If the
3785 symbol is supposed to be local, then don't actually register
3786 it. */
3787 deflt = NULL;
3788 for (t = sinfo->verdefs; t != NULL; t = t->next)
3790 if (t->globals != NULL)
3792 for (d = t->globals; d != NULL; d = d->next)
3794 if ((*d->match) (d, h->root.root.string))
3796 h->verinfo.vertree = t;
3797 break;
3801 if (d != NULL)
3802 break;
3805 if (t->locals != NULL)
3807 for (d = t->locals; d != NULL; d = d->next)
3809 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3810 deflt = t;
3811 else if ((*d->match) (d, h->root.root.string))
3813 h->verinfo.vertree = t;
3814 if (h->dynindx != -1
3815 && info->shared
3816 && ! sinfo->export_dynamic)
3818 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3819 (*bed->elf_backend_hide_symbol) (h);
3820 /* FIXME: The name of the symbol has already
3821 been recorded in the dynamic string table
3822 section. */
3824 break;
3828 if (d != NULL)
3829 break;
3833 if (deflt != NULL && h->verinfo.vertree == NULL)
3835 h->verinfo.vertree = deflt;
3836 if (h->dynindx != -1
3837 && info->shared
3838 && ! sinfo->export_dynamic)
3840 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3841 (*bed->elf_backend_hide_symbol) (h);
3842 /* FIXME: The name of the symbol has already been
3843 recorded in the dynamic string table section. */
3848 return true;
3851 /* Final phase of ELF linker. */
3853 /* A structure we use to avoid passing large numbers of arguments. */
3855 struct elf_final_link_info
3857 /* General link information. */
3858 struct bfd_link_info *info;
3859 /* Output BFD. */
3860 bfd *output_bfd;
3861 /* Symbol string table. */
3862 struct bfd_strtab_hash *symstrtab;
3863 /* .dynsym section. */
3864 asection *dynsym_sec;
3865 /* .hash section. */
3866 asection *hash_sec;
3867 /* symbol version section (.gnu.version). */
3868 asection *symver_sec;
3869 /* Buffer large enough to hold contents of any section. */
3870 bfd_byte *contents;
3871 /* Buffer large enough to hold external relocs of any section. */
3872 PTR external_relocs;
3873 /* Buffer large enough to hold internal relocs of any section. */
3874 Elf_Internal_Rela *internal_relocs;
3875 /* Buffer large enough to hold external local symbols of any input
3876 BFD. */
3877 Elf_External_Sym *external_syms;
3878 /* Buffer large enough to hold internal local symbols of any input
3879 BFD. */
3880 Elf_Internal_Sym *internal_syms;
3881 /* Array large enough to hold a symbol index for each local symbol
3882 of any input BFD. */
3883 long *indices;
3884 /* Array large enough to hold a section pointer for each local
3885 symbol of any input BFD. */
3886 asection **sections;
3887 /* Buffer to hold swapped out symbols. */
3888 Elf_External_Sym *symbuf;
3889 /* Number of swapped out symbols in buffer. */
3890 size_t symbuf_count;
3891 /* Number of symbols which fit in symbuf. */
3892 size_t symbuf_size;
3895 static boolean elf_link_output_sym
3896 PARAMS ((struct elf_final_link_info *, const char *,
3897 Elf_Internal_Sym *, asection *));
3898 static boolean elf_link_flush_output_syms
3899 PARAMS ((struct elf_final_link_info *));
3900 static boolean elf_link_output_extsym
3901 PARAMS ((struct elf_link_hash_entry *, PTR));
3902 static boolean elf_link_input_bfd
3903 PARAMS ((struct elf_final_link_info *, bfd *));
3904 static boolean elf_reloc_link_order
3905 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3906 struct bfd_link_order *));
3908 /* This struct is used to pass information to elf_link_output_extsym. */
3910 struct elf_outext_info
3912 boolean failed;
3913 boolean localsyms;
3914 struct elf_final_link_info *finfo;
3917 /* Compute the size of, and allocate space for, REL_HDR which is the
3918 section header for a section containing relocations for O. */
3920 static boolean
3921 elf_link_size_reloc_section (abfd, rel_hdr, o)
3922 bfd *abfd;
3923 Elf_Internal_Shdr *rel_hdr;
3924 asection *o;
3926 register struct elf_link_hash_entry **p, **pend;
3927 unsigned reloc_count;
3929 /* Figure out how many relocations there will be. */
3930 if (rel_hdr == &elf_section_data (o)->rel_hdr)
3931 reloc_count = elf_section_data (o)->rel_count;
3932 else
3933 reloc_count = elf_section_data (o)->rel_count2;
3935 /* That allows us to calculate the size of the section. */
3936 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
3938 /* The contents field must last into write_object_contents, so we
3939 allocate it with bfd_alloc rather than malloc. */
3940 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3941 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3942 return false;
3944 /* We only allocate one set of hash entries, so we only do it the
3945 first time we are called. */
3946 if (elf_section_data (o)->rel_hashes == NULL)
3948 p = ((struct elf_link_hash_entry **)
3949 bfd_malloc (o->reloc_count
3950 * sizeof (struct elf_link_hash_entry *)));
3951 if (p == NULL && o->reloc_count != 0)
3952 return false;
3954 elf_section_data (o)->rel_hashes = p;
3955 pend = p + o->reloc_count;
3956 for (; p < pend; p++)
3957 *p = NULL;
3960 return true;
3963 /* When performing a relocateable link, the input relocations are
3964 preserved. But, if they reference global symbols, the indices
3965 referenced must be updated. Update all the relocations in
3966 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
3968 static void
3969 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
3970 bfd *abfd;
3971 Elf_Internal_Shdr *rel_hdr;
3972 unsigned int count;
3973 struct elf_link_hash_entry **rel_hash;
3975 unsigned int i;
3977 for (i = 0; i < count; i++, rel_hash++)
3979 if (*rel_hash == NULL)
3980 continue;
3982 BFD_ASSERT ((*rel_hash)->indx >= 0);
3984 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3986 Elf_External_Rel *erel;
3987 Elf_Internal_Rel irel;
3989 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3990 elf_swap_reloc_in (abfd, erel, &irel);
3991 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3992 ELF_R_TYPE (irel.r_info));
3993 elf_swap_reloc_out (abfd, &irel, erel);
3995 else
3997 Elf_External_Rela *erela;
3998 Elf_Internal_Rela irela;
4000 BFD_ASSERT (rel_hdr->sh_entsize
4001 == sizeof (Elf_External_Rela));
4003 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4004 elf_swap_reloca_in (abfd, erela, &irela);
4005 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4006 ELF_R_TYPE (irela.r_info));
4007 elf_swap_reloca_out (abfd, &irela, erela);
4012 /* Do the final step of an ELF link. */
4014 boolean
4015 elf_bfd_final_link (abfd, info)
4016 bfd *abfd;
4017 struct bfd_link_info *info;
4019 boolean dynamic;
4020 bfd *dynobj;
4021 struct elf_final_link_info finfo;
4022 register asection *o;
4023 register struct bfd_link_order *p;
4024 register bfd *sub;
4025 size_t max_contents_size;
4026 size_t max_external_reloc_size;
4027 size_t max_internal_reloc_count;
4028 size_t max_sym_count;
4029 file_ptr off;
4030 Elf_Internal_Sym elfsym;
4031 unsigned int i;
4032 Elf_Internal_Shdr *symtab_hdr;
4033 Elf_Internal_Shdr *symstrtab_hdr;
4034 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4035 struct elf_outext_info eoinfo;
4037 if (info->shared)
4038 abfd->flags |= DYNAMIC;
4040 dynamic = elf_hash_table (info)->dynamic_sections_created;
4041 dynobj = elf_hash_table (info)->dynobj;
4043 finfo.info = info;
4044 finfo.output_bfd = abfd;
4045 finfo.symstrtab = elf_stringtab_init ();
4046 if (finfo.symstrtab == NULL)
4047 return false;
4049 if (! dynamic)
4051 finfo.dynsym_sec = NULL;
4052 finfo.hash_sec = NULL;
4053 finfo.symver_sec = NULL;
4055 else
4057 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4058 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4059 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4060 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4061 /* Note that it is OK if symver_sec is NULL. */
4064 finfo.contents = NULL;
4065 finfo.external_relocs = NULL;
4066 finfo.internal_relocs = NULL;
4067 finfo.external_syms = NULL;
4068 finfo.internal_syms = NULL;
4069 finfo.indices = NULL;
4070 finfo.sections = NULL;
4071 finfo.symbuf = NULL;
4072 finfo.symbuf_count = 0;
4074 /* Count up the number of relocations we will output for each output
4075 section, so that we know the sizes of the reloc sections. We
4076 also figure out some maximum sizes. */
4077 max_contents_size = 0;
4078 max_external_reloc_size = 0;
4079 max_internal_reloc_count = 0;
4080 max_sym_count = 0;
4081 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4083 o->reloc_count = 0;
4085 for (p = o->link_order_head; p != NULL; p = p->next)
4087 if (p->type == bfd_section_reloc_link_order
4088 || p->type == bfd_symbol_reloc_link_order)
4089 ++o->reloc_count;
4090 else if (p->type == bfd_indirect_link_order)
4092 asection *sec;
4094 sec = p->u.indirect.section;
4096 /* Mark all sections which are to be included in the
4097 link. This will normally be every section. We need
4098 to do this so that we can identify any sections which
4099 the linker has decided to not include. */
4100 sec->linker_mark = true;
4102 if (info->relocateable || info->emitrelocations)
4103 o->reloc_count += sec->reloc_count;
4105 if (sec->_raw_size > max_contents_size)
4106 max_contents_size = sec->_raw_size;
4107 if (sec->_cooked_size > max_contents_size)
4108 max_contents_size = sec->_cooked_size;
4110 /* We are interested in just local symbols, not all
4111 symbols. */
4112 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4113 && (sec->owner->flags & DYNAMIC) == 0)
4115 size_t sym_count;
4117 if (elf_bad_symtab (sec->owner))
4118 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4119 / sizeof (Elf_External_Sym));
4120 else
4121 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4123 if (sym_count > max_sym_count)
4124 max_sym_count = sym_count;
4126 if ((sec->flags & SEC_RELOC) != 0)
4128 size_t ext_size;
4130 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4131 if (ext_size > max_external_reloc_size)
4132 max_external_reloc_size = ext_size;
4133 if (sec->reloc_count > max_internal_reloc_count)
4134 max_internal_reloc_count = sec->reloc_count;
4140 if (o->reloc_count > 0)
4141 o->flags |= SEC_RELOC;
4142 else
4144 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4145 set it (this is probably a bug) and if it is set
4146 assign_section_numbers will create a reloc section. */
4147 o->flags &=~ SEC_RELOC;
4150 /* If the SEC_ALLOC flag is not set, force the section VMA to
4151 zero. This is done in elf_fake_sections as well, but forcing
4152 the VMA to 0 here will ensure that relocs against these
4153 sections are handled correctly. */
4154 if ((o->flags & SEC_ALLOC) == 0
4155 && ! o->user_set_vma)
4156 o->vma = 0;
4159 /* Figure out the file positions for everything but the symbol table
4160 and the relocs. We set symcount to force assign_section_numbers
4161 to create a symbol table. */
4162 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4163 BFD_ASSERT (! abfd->output_has_begun);
4164 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4165 goto error_return;
4167 /* Figure out how many relocations we will have in each section.
4168 Just using RELOC_COUNT isn't good enough since that doesn't
4169 maintain a separate value for REL vs. RELA relocations. */
4170 if (info->relocateable || info->emitrelocations)
4171 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4172 for (o = sub->sections; o != NULL; o = o->next)
4174 asection *output_section;
4176 if (! o->linker_mark)
4178 /* This section was omitted from the link. */
4179 continue;
4182 output_section = o->output_section;
4184 if (output_section != NULL
4185 && (o->flags & SEC_RELOC) != 0)
4187 struct bfd_elf_section_data *esdi
4188 = elf_section_data (o);
4189 struct bfd_elf_section_data *esdo
4190 = elf_section_data (output_section);
4191 unsigned int *rel_count;
4192 unsigned int *rel_count2;
4194 /* We must be careful to add the relocation froms the
4195 input section to the right output count. */
4196 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4198 rel_count = &esdo->rel_count;
4199 rel_count2 = &esdo->rel_count2;
4201 else
4203 rel_count = &esdo->rel_count2;
4204 rel_count2 = &esdo->rel_count;
4207 *rel_count += (esdi->rel_hdr.sh_size
4208 / esdi->rel_hdr.sh_entsize);
4209 if (esdi->rel_hdr2)
4210 *rel_count2 += (esdi->rel_hdr2->sh_size
4211 / esdi->rel_hdr2->sh_entsize);
4215 /* That created the reloc sections. Set their sizes, and assign
4216 them file positions, and allocate some buffers. */
4217 for (o = abfd->sections; o != NULL; o = o->next)
4219 if ((o->flags & SEC_RELOC) != 0)
4221 if (!elf_link_size_reloc_section (abfd,
4222 &elf_section_data (o)->rel_hdr,
4224 goto error_return;
4226 if (elf_section_data (o)->rel_hdr2
4227 && !elf_link_size_reloc_section (abfd,
4228 elf_section_data (o)->rel_hdr2,
4230 goto error_return;
4233 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4234 to count upwards while actually outputting the relocations. */
4235 elf_section_data (o)->rel_count = 0;
4236 elf_section_data (o)->rel_count2 = 0;
4239 _bfd_elf_assign_file_positions_for_relocs (abfd);
4241 /* We have now assigned file positions for all the sections except
4242 .symtab and .strtab. We start the .symtab section at the current
4243 file position, and write directly to it. We build the .strtab
4244 section in memory. */
4245 bfd_get_symcount (abfd) = 0;
4246 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4247 /* sh_name is set in prep_headers. */
4248 symtab_hdr->sh_type = SHT_SYMTAB;
4249 symtab_hdr->sh_flags = 0;
4250 symtab_hdr->sh_addr = 0;
4251 symtab_hdr->sh_size = 0;
4252 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4253 /* sh_link is set in assign_section_numbers. */
4254 /* sh_info is set below. */
4255 /* sh_offset is set just below. */
4256 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4258 off = elf_tdata (abfd)->next_file_pos;
4259 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4261 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4262 incorrect. We do not yet know the size of the .symtab section.
4263 We correct next_file_pos below, after we do know the size. */
4265 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4266 continuously seeking to the right position in the file. */
4267 if (! info->keep_memory || max_sym_count < 20)
4268 finfo.symbuf_size = 20;
4269 else
4270 finfo.symbuf_size = max_sym_count;
4271 finfo.symbuf = ((Elf_External_Sym *)
4272 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4273 if (finfo.symbuf == NULL)
4274 goto error_return;
4276 /* Start writing out the symbol table. The first symbol is always a
4277 dummy symbol. */
4278 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4280 elfsym.st_value = 0;
4281 elfsym.st_size = 0;
4282 elfsym.st_info = 0;
4283 elfsym.st_other = 0;
4284 elfsym.st_shndx = SHN_UNDEF;
4285 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4286 &elfsym, bfd_und_section_ptr))
4287 goto error_return;
4290 #if 0
4291 /* Some standard ELF linkers do this, but we don't because it causes
4292 bootstrap comparison failures. */
4293 /* Output a file symbol for the output file as the second symbol.
4294 We output this even if we are discarding local symbols, although
4295 I'm not sure if this is correct. */
4296 elfsym.st_value = 0;
4297 elfsym.st_size = 0;
4298 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4299 elfsym.st_other = 0;
4300 elfsym.st_shndx = SHN_ABS;
4301 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4302 &elfsym, bfd_abs_section_ptr))
4303 goto error_return;
4304 #endif
4306 /* Output a symbol for each section. We output these even if we are
4307 discarding local symbols, since they are used for relocs. These
4308 symbols have no names. We store the index of each one in the
4309 index field of the section, so that we can find it again when
4310 outputting relocs. */
4311 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4313 elfsym.st_size = 0;
4314 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4315 elfsym.st_other = 0;
4316 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4318 o = section_from_elf_index (abfd, i);
4319 if (o != NULL)
4320 o->target_index = bfd_get_symcount (abfd);
4321 elfsym.st_shndx = i;
4322 if (info->relocateable || o == NULL)
4323 elfsym.st_value = 0;
4324 else
4325 elfsym.st_value = o->vma;
4326 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4327 &elfsym, o))
4328 goto error_return;
4332 /* Allocate some memory to hold information read in from the input
4333 files. */
4334 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4335 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4336 finfo.internal_relocs = ((Elf_Internal_Rela *)
4337 bfd_malloc (max_internal_reloc_count
4338 * sizeof (Elf_Internal_Rela)
4339 * bed->s->int_rels_per_ext_rel));
4340 finfo.external_syms = ((Elf_External_Sym *)
4341 bfd_malloc (max_sym_count
4342 * sizeof (Elf_External_Sym)));
4343 finfo.internal_syms = ((Elf_Internal_Sym *)
4344 bfd_malloc (max_sym_count
4345 * sizeof (Elf_Internal_Sym)));
4346 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4347 finfo.sections = ((asection **)
4348 bfd_malloc (max_sym_count * sizeof (asection *)));
4349 if ((finfo.contents == NULL && max_contents_size != 0)
4350 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4351 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4352 || (finfo.external_syms == NULL && max_sym_count != 0)
4353 || (finfo.internal_syms == NULL && max_sym_count != 0)
4354 || (finfo.indices == NULL && max_sym_count != 0)
4355 || (finfo.sections == NULL && max_sym_count != 0))
4356 goto error_return;
4358 /* Since ELF permits relocations to be against local symbols, we
4359 must have the local symbols available when we do the relocations.
4360 Since we would rather only read the local symbols once, and we
4361 would rather not keep them in memory, we handle all the
4362 relocations for a single input file at the same time.
4364 Unfortunately, there is no way to know the total number of local
4365 symbols until we have seen all of them, and the local symbol
4366 indices precede the global symbol indices. This means that when
4367 we are generating relocateable output, and we see a reloc against
4368 a global symbol, we can not know the symbol index until we have
4369 finished examining all the local symbols to see which ones we are
4370 going to output. To deal with this, we keep the relocations in
4371 memory, and don't output them until the end of the link. This is
4372 an unfortunate waste of memory, but I don't see a good way around
4373 it. Fortunately, it only happens when performing a relocateable
4374 link, which is not the common case. FIXME: If keep_memory is set
4375 we could write the relocs out and then read them again; I don't
4376 know how bad the memory loss will be. */
4378 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4379 sub->output_has_begun = false;
4380 for (o = abfd->sections; o != NULL; o = o->next)
4382 for (p = o->link_order_head; p != NULL; p = p->next)
4384 if (p->type == bfd_indirect_link_order
4385 && (bfd_get_flavour (p->u.indirect.section->owner)
4386 == bfd_target_elf_flavour))
4388 sub = p->u.indirect.section->owner;
4389 if (! sub->output_has_begun)
4391 if (! elf_link_input_bfd (&finfo, sub))
4392 goto error_return;
4393 sub->output_has_begun = true;
4396 else if (p->type == bfd_section_reloc_link_order
4397 || p->type == bfd_symbol_reloc_link_order)
4399 if (! elf_reloc_link_order (abfd, info, o, p))
4400 goto error_return;
4402 else
4404 if (! _bfd_default_link_order (abfd, info, o, p))
4405 goto error_return;
4410 /* That wrote out all the local symbols. Finish up the symbol table
4411 with the global symbols. Even if we want to strip everything we
4412 can, we still need to deal with those global symbols that got
4413 converted to local in a version script. */
4415 if (info->shared)
4417 /* Output any global symbols that got converted to local in a
4418 version script. We do this in a separate step since ELF
4419 requires all local symbols to appear prior to any global
4420 symbols. FIXME: We should only do this if some global
4421 symbols were, in fact, converted to become local. FIXME:
4422 Will this work correctly with the Irix 5 linker? */
4423 eoinfo.failed = false;
4424 eoinfo.finfo = &finfo;
4425 eoinfo.localsyms = true;
4426 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4427 (PTR) &eoinfo);
4428 if (eoinfo.failed)
4429 return false;
4432 /* The sh_info field records the index of the first non local symbol. */
4433 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4435 if (dynamic)
4437 Elf_Internal_Sym sym;
4438 Elf_External_Sym *dynsym =
4439 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4440 long last_local = 0;
4442 /* Write out the section symbols for the output sections. */
4443 if (info->shared)
4445 asection *s;
4447 sym.st_size = 0;
4448 sym.st_name = 0;
4449 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4450 sym.st_other = 0;
4452 for (s = abfd->sections; s != NULL; s = s->next)
4454 int indx;
4455 indx = elf_section_data (s)->this_idx;
4456 BFD_ASSERT (indx > 0);
4457 sym.st_shndx = indx;
4458 sym.st_value = s->vma;
4460 elf_swap_symbol_out (abfd, &sym,
4461 dynsym + elf_section_data (s)->dynindx);
4464 last_local = bfd_count_sections (abfd);
4467 /* Write out the local dynsyms. */
4468 if (elf_hash_table (info)->dynlocal)
4470 struct elf_link_local_dynamic_entry *e;
4471 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4473 asection *s;
4475 sym.st_size = e->isym.st_size;
4476 sym.st_other = e->isym.st_other;
4478 /* Copy the internal symbol as is.
4479 Note that we saved a word of storage and overwrote
4480 the original st_name with the dynstr_index. */
4481 sym = e->isym;
4483 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4485 s = bfd_section_from_elf_index (e->input_bfd,
4486 e->isym.st_shndx);
4488 sym.st_shndx =
4489 elf_section_data (s->output_section)->this_idx;
4490 sym.st_value = (s->output_section->vma
4491 + s->output_offset
4492 + e->isym.st_value);
4495 if (last_local < e->dynindx)
4496 last_local = e->dynindx;
4498 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4502 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4503 last_local + 1;
4506 /* We get the global symbols from the hash table. */
4507 eoinfo.failed = false;
4508 eoinfo.localsyms = false;
4509 eoinfo.finfo = &finfo;
4510 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4511 (PTR) &eoinfo);
4512 if (eoinfo.failed)
4513 return false;
4515 /* If backend needs to output some symbols not present in the hash
4516 table, do it now. */
4517 if (bed->elf_backend_output_arch_syms)
4519 if (! (*bed->elf_backend_output_arch_syms)
4520 (abfd, info, (PTR) &finfo,
4521 (boolean (*) PARAMS ((PTR, const char *,
4522 Elf_Internal_Sym *, asection *)))
4523 elf_link_output_sym))
4524 return false;
4527 /* Flush all symbols to the file. */
4528 if (! elf_link_flush_output_syms (&finfo))
4529 return false;
4531 /* Now we know the size of the symtab section. */
4532 off += symtab_hdr->sh_size;
4534 /* Finish up and write out the symbol string table (.strtab)
4535 section. */
4536 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4537 /* sh_name was set in prep_headers. */
4538 symstrtab_hdr->sh_type = SHT_STRTAB;
4539 symstrtab_hdr->sh_flags = 0;
4540 symstrtab_hdr->sh_addr = 0;
4541 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4542 symstrtab_hdr->sh_entsize = 0;
4543 symstrtab_hdr->sh_link = 0;
4544 symstrtab_hdr->sh_info = 0;
4545 /* sh_offset is set just below. */
4546 symstrtab_hdr->sh_addralign = 1;
4548 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4549 elf_tdata (abfd)->next_file_pos = off;
4551 if (bfd_get_symcount (abfd) > 0)
4553 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4554 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4555 return false;
4558 /* Adjust the relocs to have the correct symbol indices. */
4559 for (o = abfd->sections; o != NULL; o = o->next)
4561 if ((o->flags & SEC_RELOC) == 0)
4562 continue;
4564 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4565 elf_section_data (o)->rel_count,
4566 elf_section_data (o)->rel_hashes);
4567 if (elf_section_data (o)->rel_hdr2 != NULL)
4568 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4569 elf_section_data (o)->rel_count2,
4570 (elf_section_data (o)->rel_hashes
4571 + elf_section_data (o)->rel_count));
4573 /* Set the reloc_count field to 0 to prevent write_relocs from
4574 trying to swap the relocs out itself. */
4575 o->reloc_count = 0;
4578 /* If we are linking against a dynamic object, or generating a
4579 shared library, finish up the dynamic linking information. */
4580 if (dynamic)
4582 Elf_External_Dyn *dyncon, *dynconend;
4584 /* Fix up .dynamic entries. */
4585 o = bfd_get_section_by_name (dynobj, ".dynamic");
4586 BFD_ASSERT (o != NULL);
4588 dyncon = (Elf_External_Dyn *) o->contents;
4589 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4590 for (; dyncon < dynconend; dyncon++)
4592 Elf_Internal_Dyn dyn;
4593 const char *name;
4594 unsigned int type;
4596 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4598 switch (dyn.d_tag)
4600 default:
4601 break;
4602 case DT_INIT:
4603 name = info->init_function;
4604 goto get_sym;
4605 case DT_FINI:
4606 name = info->fini_function;
4607 get_sym:
4609 struct elf_link_hash_entry *h;
4611 h = elf_link_hash_lookup (elf_hash_table (info), name,
4612 false, false, true);
4613 if (h != NULL
4614 && (h->root.type == bfd_link_hash_defined
4615 || h->root.type == bfd_link_hash_defweak))
4617 dyn.d_un.d_val = h->root.u.def.value;
4618 o = h->root.u.def.section;
4619 if (o->output_section != NULL)
4620 dyn.d_un.d_val += (o->output_section->vma
4621 + o->output_offset);
4622 else
4624 /* The symbol is imported from another shared
4625 library and does not apply to this one. */
4626 dyn.d_un.d_val = 0;
4629 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4632 break;
4634 case DT_HASH:
4635 name = ".hash";
4636 goto get_vma;
4637 case DT_STRTAB:
4638 name = ".dynstr";
4639 goto get_vma;
4640 case DT_SYMTAB:
4641 name = ".dynsym";
4642 goto get_vma;
4643 case DT_VERDEF:
4644 name = ".gnu.version_d";
4645 goto get_vma;
4646 case DT_VERNEED:
4647 name = ".gnu.version_r";
4648 goto get_vma;
4649 case DT_VERSYM:
4650 name = ".gnu.version";
4651 get_vma:
4652 o = bfd_get_section_by_name (abfd, name);
4653 BFD_ASSERT (o != NULL);
4654 dyn.d_un.d_ptr = o->vma;
4655 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4656 break;
4658 case DT_REL:
4659 case DT_RELA:
4660 case DT_RELSZ:
4661 case DT_RELASZ:
4662 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4663 type = SHT_REL;
4664 else
4665 type = SHT_RELA;
4666 dyn.d_un.d_val = 0;
4667 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4669 Elf_Internal_Shdr *hdr;
4671 hdr = elf_elfsections (abfd)[i];
4672 if (hdr->sh_type == type
4673 && (hdr->sh_flags & SHF_ALLOC) != 0)
4675 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4676 dyn.d_un.d_val += hdr->sh_size;
4677 else
4679 if (dyn.d_un.d_val == 0
4680 || hdr->sh_addr < dyn.d_un.d_val)
4681 dyn.d_un.d_val = hdr->sh_addr;
4685 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4686 break;
4691 /* If we have created any dynamic sections, then output them. */
4692 if (dynobj != NULL)
4694 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4695 goto error_return;
4697 for (o = dynobj->sections; o != NULL; o = o->next)
4699 if ((o->flags & SEC_HAS_CONTENTS) == 0
4700 || o->_raw_size == 0)
4701 continue;
4702 if ((o->flags & SEC_LINKER_CREATED) == 0)
4704 /* At this point, we are only interested in sections
4705 created by elf_link_create_dynamic_sections. */
4706 continue;
4708 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4709 != SHT_STRTAB)
4710 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4712 if (! bfd_set_section_contents (abfd, o->output_section,
4713 o->contents, o->output_offset,
4714 o->_raw_size))
4715 goto error_return;
4717 else
4719 file_ptr off;
4721 /* The contents of the .dynstr section are actually in a
4722 stringtab. */
4723 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4724 if (bfd_seek (abfd, off, SEEK_SET) != 0
4725 || ! _bfd_stringtab_emit (abfd,
4726 elf_hash_table (info)->dynstr))
4727 goto error_return;
4732 /* If we have optimized stabs strings, output them. */
4733 if (elf_hash_table (info)->stab_info != NULL)
4735 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4736 goto error_return;
4739 if (finfo.symstrtab != NULL)
4740 _bfd_stringtab_free (finfo.symstrtab);
4741 if (finfo.contents != NULL)
4742 free (finfo.contents);
4743 if (finfo.external_relocs != NULL)
4744 free (finfo.external_relocs);
4745 if (finfo.internal_relocs != NULL)
4746 free (finfo.internal_relocs);
4747 if (finfo.external_syms != NULL)
4748 free (finfo.external_syms);
4749 if (finfo.internal_syms != NULL)
4750 free (finfo.internal_syms);
4751 if (finfo.indices != NULL)
4752 free (finfo.indices);
4753 if (finfo.sections != NULL)
4754 free (finfo.sections);
4755 if (finfo.symbuf != NULL)
4756 free (finfo.symbuf);
4757 for (o = abfd->sections; o != NULL; o = o->next)
4759 if ((o->flags & SEC_RELOC) != 0
4760 && elf_section_data (o)->rel_hashes != NULL)
4761 free (elf_section_data (o)->rel_hashes);
4764 elf_tdata (abfd)->linker = true;
4766 return true;
4768 error_return:
4769 if (finfo.symstrtab != NULL)
4770 _bfd_stringtab_free (finfo.symstrtab);
4771 if (finfo.contents != NULL)
4772 free (finfo.contents);
4773 if (finfo.external_relocs != NULL)
4774 free (finfo.external_relocs);
4775 if (finfo.internal_relocs != NULL)
4776 free (finfo.internal_relocs);
4777 if (finfo.external_syms != NULL)
4778 free (finfo.external_syms);
4779 if (finfo.internal_syms != NULL)
4780 free (finfo.internal_syms);
4781 if (finfo.indices != NULL)
4782 free (finfo.indices);
4783 if (finfo.sections != NULL)
4784 free (finfo.sections);
4785 if (finfo.symbuf != NULL)
4786 free (finfo.symbuf);
4787 for (o = abfd->sections; o != NULL; o = o->next)
4789 if ((o->flags & SEC_RELOC) != 0
4790 && elf_section_data (o)->rel_hashes != NULL)
4791 free (elf_section_data (o)->rel_hashes);
4794 return false;
4797 /* Add a symbol to the output symbol table. */
4799 static boolean
4800 elf_link_output_sym (finfo, name, elfsym, input_sec)
4801 struct elf_final_link_info *finfo;
4802 const char *name;
4803 Elf_Internal_Sym *elfsym;
4804 asection *input_sec;
4806 boolean (*output_symbol_hook) PARAMS ((bfd *,
4807 struct bfd_link_info *info,
4808 const char *,
4809 Elf_Internal_Sym *,
4810 asection *));
4812 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4813 elf_backend_link_output_symbol_hook;
4814 if (output_symbol_hook != NULL)
4816 if (! ((*output_symbol_hook)
4817 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4818 return false;
4821 if (name == (const char *) NULL || *name == '\0')
4822 elfsym->st_name = 0;
4823 else if (input_sec->flags & SEC_EXCLUDE)
4824 elfsym->st_name = 0;
4825 else
4827 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4828 name, true,
4829 false);
4830 if (elfsym->st_name == (unsigned long) -1)
4831 return false;
4834 if (finfo->symbuf_count >= finfo->symbuf_size)
4836 if (! elf_link_flush_output_syms (finfo))
4837 return false;
4840 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4841 (PTR) (finfo->symbuf + finfo->symbuf_count));
4842 ++finfo->symbuf_count;
4844 ++ bfd_get_symcount (finfo->output_bfd);
4846 return true;
4849 /* Flush the output symbols to the file. */
4851 static boolean
4852 elf_link_flush_output_syms (finfo)
4853 struct elf_final_link_info *finfo;
4855 if (finfo->symbuf_count > 0)
4857 Elf_Internal_Shdr *symtab;
4859 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4861 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4862 SEEK_SET) != 0
4863 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4864 sizeof (Elf_External_Sym), finfo->output_bfd)
4865 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4866 return false;
4868 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4870 finfo->symbuf_count = 0;
4873 return true;
4876 /* Add an external symbol to the symbol table. This is called from
4877 the hash table traversal routine. When generating a shared object,
4878 we go through the symbol table twice. The first time we output
4879 anything that might have been forced to local scope in a version
4880 script. The second time we output the symbols that are still
4881 global symbols. */
4883 static boolean
4884 elf_link_output_extsym (h, data)
4885 struct elf_link_hash_entry *h;
4886 PTR data;
4888 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4889 struct elf_final_link_info *finfo = eoinfo->finfo;
4890 boolean strip;
4891 Elf_Internal_Sym sym;
4892 asection *input_sec;
4894 /* Decide whether to output this symbol in this pass. */
4895 if (eoinfo->localsyms)
4897 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4898 return true;
4900 else
4902 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4903 return true;
4906 /* If we are not creating a shared library, and this symbol is
4907 referenced by a shared library but is not defined anywhere, then
4908 warn that it is undefined. If we do not do this, the runtime
4909 linker will complain that the symbol is undefined when the
4910 program is run. We don't have to worry about symbols that are
4911 referenced by regular files, because we will already have issued
4912 warnings for them. */
4913 if (! finfo->info->relocateable
4914 && ! (finfo->info->shared
4915 && !finfo->info->no_undefined)
4916 && h->root.type == bfd_link_hash_undefined
4917 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4918 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4920 if (! ((*finfo->info->callbacks->undefined_symbol)
4921 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4922 (asection *) NULL, 0, true)))
4924 eoinfo->failed = true;
4925 return false;
4929 /* We don't want to output symbols that have never been mentioned by
4930 a regular file, or that we have been told to strip. However, if
4931 h->indx is set to -2, the symbol is used by a reloc and we must
4932 output it. */
4933 if (h->indx == -2)
4934 strip = false;
4935 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4936 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4937 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4938 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4939 strip = true;
4940 else if (finfo->info->strip == strip_all
4941 || (finfo->info->strip == strip_some
4942 && bfd_hash_lookup (finfo->info->keep_hash,
4943 h->root.root.string,
4944 false, false) == NULL))
4945 strip = true;
4946 else
4947 strip = false;
4949 /* If we're stripping it, and it's not a dynamic symbol, there's
4950 nothing else to do unless it is a forced local symbol. */
4951 if (strip
4952 && h->dynindx == -1
4953 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4954 return true;
4956 sym.st_value = 0;
4957 sym.st_size = h->size;
4958 sym.st_other = h->other;
4959 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4960 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4961 else if (h->root.type == bfd_link_hash_undefweak
4962 || h->root.type == bfd_link_hash_defweak)
4963 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4964 else
4965 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4967 switch (h->root.type)
4969 default:
4970 case bfd_link_hash_new:
4971 abort ();
4972 return false;
4974 case bfd_link_hash_undefined:
4975 input_sec = bfd_und_section_ptr;
4976 sym.st_shndx = SHN_UNDEF;
4977 break;
4979 case bfd_link_hash_undefweak:
4980 input_sec = bfd_und_section_ptr;
4981 sym.st_shndx = SHN_UNDEF;
4982 break;
4984 case bfd_link_hash_defined:
4985 case bfd_link_hash_defweak:
4987 input_sec = h->root.u.def.section;
4988 if (input_sec->output_section != NULL)
4990 sym.st_shndx =
4991 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4992 input_sec->output_section);
4993 if (sym.st_shndx == (unsigned short) -1)
4995 (*_bfd_error_handler)
4996 (_("%s: could not find output section %s for input section %s"),
4997 bfd_get_filename (finfo->output_bfd),
4998 input_sec->output_section->name,
4999 input_sec->name);
5000 eoinfo->failed = true;
5001 return false;
5004 /* ELF symbols in relocateable files are section relative,
5005 but in nonrelocateable files they are virtual
5006 addresses. */
5007 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5008 if (! finfo->info->relocateable)
5009 sym.st_value += input_sec->output_section->vma;
5011 else
5013 BFD_ASSERT (input_sec->owner == NULL
5014 || (input_sec->owner->flags & DYNAMIC) != 0);
5015 sym.st_shndx = SHN_UNDEF;
5016 input_sec = bfd_und_section_ptr;
5019 break;
5021 case bfd_link_hash_common:
5022 input_sec = h->root.u.c.p->section;
5023 sym.st_shndx = SHN_COMMON;
5024 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5025 break;
5027 case bfd_link_hash_indirect:
5028 /* These symbols are created by symbol versioning. They point
5029 to the decorated version of the name. For example, if the
5030 symbol foo@@GNU_1.2 is the default, which should be used when
5031 foo is used with no version, then we add an indirect symbol
5032 foo which points to foo@@GNU_1.2. We ignore these symbols,
5033 since the indirected symbol is already in the hash table. If
5034 the indirect symbol is non-ELF, fall through and output it. */
5035 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
5036 return true;
5038 /* Fall through. */
5039 case bfd_link_hash_warning:
5040 /* We can't represent these symbols in ELF, although a warning
5041 symbol may have come from a .gnu.warning.SYMBOL section. We
5042 just put the target symbol in the hash table. If the target
5043 symbol does not really exist, don't do anything. */
5044 if (h->root.u.i.link->type == bfd_link_hash_new)
5045 return true;
5046 return (elf_link_output_extsym
5047 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5050 /* Give the processor backend a chance to tweak the symbol value,
5051 and also to finish up anything that needs to be done for this
5052 symbol. */
5053 if ((h->dynindx != -1
5054 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5055 && elf_hash_table (finfo->info)->dynamic_sections_created)
5057 struct elf_backend_data *bed;
5059 bed = get_elf_backend_data (finfo->output_bfd);
5060 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5061 (finfo->output_bfd, finfo->info, h, &sym)))
5063 eoinfo->failed = true;
5064 return false;
5068 /* If we are marking the symbol as undefined, and there are no
5069 non-weak references to this symbol from a regular object, then
5070 mark the symbol as weak undefined; if there are non-weak
5071 references, mark the symbol as strong. We can't do this earlier,
5072 because it might not be marked as undefined until the
5073 finish_dynamic_symbol routine gets through with it. */
5074 if (sym.st_shndx == SHN_UNDEF
5075 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5076 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5077 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5079 int bindtype;
5081 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5082 bindtype = STB_GLOBAL;
5083 else
5084 bindtype = STB_WEAK;
5085 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5088 /* If a symbol is not defined locally, we clear the visibility
5089 field. */
5090 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5091 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5093 /* If this symbol should be put in the .dynsym section, then put it
5094 there now. We have already know the symbol index. We also fill
5095 in the entry in the .hash section. */
5096 if (h->dynindx != -1
5097 && elf_hash_table (finfo->info)->dynamic_sections_created)
5099 size_t bucketcount;
5100 size_t bucket;
5101 size_t hash_entry_size;
5102 bfd_byte *bucketpos;
5103 bfd_vma chain;
5105 sym.st_name = h->dynstr_index;
5107 elf_swap_symbol_out (finfo->output_bfd, &sym,
5108 (PTR) (((Elf_External_Sym *)
5109 finfo->dynsym_sec->contents)
5110 + h->dynindx));
5112 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5113 bucket = h->elf_hash_value % bucketcount;
5114 hash_entry_size
5115 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5116 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5117 + (bucket + 2) * hash_entry_size);
5118 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5119 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5120 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5121 ((bfd_byte *) finfo->hash_sec->contents
5122 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5124 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5126 Elf_Internal_Versym iversym;
5128 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5130 if (h->verinfo.verdef == NULL)
5131 iversym.vs_vers = 0;
5132 else
5133 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5135 else
5137 if (h->verinfo.vertree == NULL)
5138 iversym.vs_vers = 1;
5139 else
5140 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5143 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5144 iversym.vs_vers |= VERSYM_HIDDEN;
5146 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5147 (((Elf_External_Versym *)
5148 finfo->symver_sec->contents)
5149 + h->dynindx));
5153 /* If we're stripping it, then it was just a dynamic symbol, and
5154 there's nothing else to do. */
5155 if (strip)
5156 return true;
5158 h->indx = bfd_get_symcount (finfo->output_bfd);
5160 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5162 eoinfo->failed = true;
5163 return false;
5166 return true;
5169 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5170 originated from the section given by INPUT_REL_HDR) to the
5171 OUTPUT_BFD. */
5173 static void
5174 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5175 internal_relocs)
5176 bfd *output_bfd;
5177 asection *input_section;
5178 Elf_Internal_Shdr *input_rel_hdr;
5179 Elf_Internal_Rela *internal_relocs;
5181 Elf_Internal_Rela *irela;
5182 Elf_Internal_Rela *irelaend;
5183 Elf_Internal_Shdr *output_rel_hdr;
5184 asection *output_section;
5185 unsigned int *rel_countp = NULL;
5187 output_section = input_section->output_section;
5188 output_rel_hdr = NULL;
5190 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5191 == input_rel_hdr->sh_entsize)
5193 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5194 rel_countp = &elf_section_data (output_section)->rel_count;
5196 else if (elf_section_data (output_section)->rel_hdr2
5197 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5198 == input_rel_hdr->sh_entsize))
5200 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5201 rel_countp = &elf_section_data (output_section)->rel_count2;
5204 BFD_ASSERT (output_rel_hdr != NULL);
5206 irela = internal_relocs;
5207 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5208 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5210 Elf_External_Rel *erel;
5212 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5213 for (; irela < irelaend; irela++, erel++)
5215 Elf_Internal_Rel irel;
5217 irel.r_offset = irela->r_offset;
5218 irel.r_info = irela->r_info;
5219 BFD_ASSERT (irela->r_addend == 0);
5220 elf_swap_reloc_out (output_bfd, &irel, erel);
5223 else
5225 Elf_External_Rela *erela;
5227 BFD_ASSERT (input_rel_hdr->sh_entsize
5228 == sizeof (Elf_External_Rela));
5229 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5230 for (; irela < irelaend; irela++, erela++)
5231 elf_swap_reloca_out (output_bfd, irela, erela);
5234 /* Bump the counter, so that we know where to add the next set of
5235 relocations. */
5236 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5239 /* Link an input file into the linker output file. This function
5240 handles all the sections and relocations of the input file at once.
5241 This is so that we only have to read the local symbols once, and
5242 don't have to keep them in memory. */
5244 static boolean
5245 elf_link_input_bfd (finfo, input_bfd)
5246 struct elf_final_link_info *finfo;
5247 bfd *input_bfd;
5249 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5250 bfd *, asection *, bfd_byte *,
5251 Elf_Internal_Rela *,
5252 Elf_Internal_Sym *, asection **));
5253 bfd *output_bfd;
5254 Elf_Internal_Shdr *symtab_hdr;
5255 size_t locsymcount;
5256 size_t extsymoff;
5257 Elf_External_Sym *external_syms;
5258 Elf_External_Sym *esym;
5259 Elf_External_Sym *esymend;
5260 Elf_Internal_Sym *isym;
5261 long *pindex;
5262 asection **ppsection;
5263 asection *o;
5264 struct elf_backend_data *bed;
5266 output_bfd = finfo->output_bfd;
5267 bed = get_elf_backend_data (output_bfd);
5268 relocate_section = bed->elf_backend_relocate_section;
5270 /* If this is a dynamic object, we don't want to do anything here:
5271 we don't want the local symbols, and we don't want the section
5272 contents. */
5273 if ((input_bfd->flags & DYNAMIC) != 0)
5274 return true;
5276 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5277 if (elf_bad_symtab (input_bfd))
5279 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5280 extsymoff = 0;
5282 else
5284 locsymcount = symtab_hdr->sh_info;
5285 extsymoff = symtab_hdr->sh_info;
5288 /* Read the local symbols. */
5289 if (symtab_hdr->contents != NULL)
5290 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5291 else if (locsymcount == 0)
5292 external_syms = NULL;
5293 else
5295 external_syms = finfo->external_syms;
5296 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5297 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5298 locsymcount, input_bfd)
5299 != locsymcount * sizeof (Elf_External_Sym)))
5300 return false;
5303 /* Swap in the local symbols and write out the ones which we know
5304 are going into the output file. */
5305 esym = external_syms;
5306 esymend = esym + locsymcount;
5307 isym = finfo->internal_syms;
5308 pindex = finfo->indices;
5309 ppsection = finfo->sections;
5310 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5312 asection *isec;
5313 const char *name;
5314 Elf_Internal_Sym osym;
5316 elf_swap_symbol_in (input_bfd, esym, isym);
5317 *pindex = -1;
5319 if (elf_bad_symtab (input_bfd))
5321 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5323 *ppsection = NULL;
5324 continue;
5328 if (isym->st_shndx == SHN_UNDEF)
5329 isec = bfd_und_section_ptr;
5330 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5331 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5332 else if (isym->st_shndx == SHN_ABS)
5333 isec = bfd_abs_section_ptr;
5334 else if (isym->st_shndx == SHN_COMMON)
5335 isec = bfd_com_section_ptr;
5336 else
5338 /* Who knows? */
5339 isec = NULL;
5342 *ppsection = isec;
5344 /* Don't output the first, undefined, symbol. */
5345 if (esym == external_syms)
5346 continue;
5348 /* If we are stripping all symbols, we don't want to output this
5349 one. */
5350 if (finfo->info->strip == strip_all)
5351 continue;
5353 /* We never output section symbols. Instead, we use the section
5354 symbol of the corresponding section in the output file. */
5355 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5356 continue;
5358 /* If we are discarding all local symbols, we don't want to
5359 output this one. If we are generating a relocateable output
5360 file, then some of the local symbols may be required by
5361 relocs; we output them below as we discover that they are
5362 needed. */
5363 if (finfo->info->discard == discard_all)
5364 continue;
5366 /* If this symbol is defined in a section which we are
5367 discarding, we don't need to keep it, but note that
5368 linker_mark is only reliable for sections that have contents.
5369 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5370 as well as linker_mark. */
5371 if (isym->st_shndx > 0
5372 && isym->st_shndx < SHN_LORESERVE
5373 && isec != NULL
5374 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5375 || (! finfo->info->relocateable
5376 && (isec->flags & SEC_EXCLUDE) != 0)))
5377 continue;
5379 /* Get the name of the symbol. */
5380 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5381 isym->st_name);
5382 if (name == NULL)
5383 return false;
5385 /* See if we are discarding symbols with this name. */
5386 if ((finfo->info->strip == strip_some
5387 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5388 == NULL))
5389 || (finfo->info->discard == discard_l
5390 && bfd_is_local_label_name (input_bfd, name)))
5391 continue;
5393 /* If we get here, we are going to output this symbol. */
5395 osym = *isym;
5397 /* Adjust the section index for the output file. */
5398 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5399 isec->output_section);
5400 if (osym.st_shndx == (unsigned short) -1)
5401 return false;
5403 *pindex = bfd_get_symcount (output_bfd);
5405 /* ELF symbols in relocateable files are section relative, but
5406 in executable files they are virtual addresses. Note that
5407 this code assumes that all ELF sections have an associated
5408 BFD section with a reasonable value for output_offset; below
5409 we assume that they also have a reasonable value for
5410 output_section. Any special sections must be set up to meet
5411 these requirements. */
5412 osym.st_value += isec->output_offset;
5413 if (! finfo->info->relocateable)
5414 osym.st_value += isec->output_section->vma;
5416 if (! elf_link_output_sym (finfo, name, &osym, isec))
5417 return false;
5420 /* Relocate the contents of each section. */
5421 for (o = input_bfd->sections; o != NULL; o = o->next)
5423 bfd_byte *contents;
5425 if (! o->linker_mark)
5427 /* This section was omitted from the link. */
5428 continue;
5431 if ((o->flags & SEC_HAS_CONTENTS) == 0
5432 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5433 continue;
5435 if ((o->flags & SEC_LINKER_CREATED) != 0)
5437 /* Section was created by elf_link_create_dynamic_sections
5438 or somesuch. */
5439 continue;
5442 /* Get the contents of the section. They have been cached by a
5443 relaxation routine. Note that o is a section in an input
5444 file, so the contents field will not have been set by any of
5445 the routines which work on output files. */
5446 if (elf_section_data (o)->this_hdr.contents != NULL)
5447 contents = elf_section_data (o)->this_hdr.contents;
5448 else
5450 contents = finfo->contents;
5451 if (! bfd_get_section_contents (input_bfd, o, contents,
5452 (file_ptr) 0, o->_raw_size))
5453 return false;
5456 if ((o->flags & SEC_RELOC) != 0)
5458 Elf_Internal_Rela *internal_relocs;
5460 /* Get the swapped relocs. */
5461 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5462 (input_bfd, o, finfo->external_relocs,
5463 finfo->internal_relocs, false));
5464 if (internal_relocs == NULL
5465 && o->reloc_count > 0)
5466 return false;
5468 /* Relocate the section by invoking a back end routine.
5470 The back end routine is responsible for adjusting the
5471 section contents as necessary, and (if using Rela relocs
5472 and generating a relocateable output file) adjusting the
5473 reloc addend as necessary.
5475 The back end routine does not have to worry about setting
5476 the reloc address or the reloc symbol index.
5478 The back end routine is given a pointer to the swapped in
5479 internal symbols, and can access the hash table entries
5480 for the external symbols via elf_sym_hashes (input_bfd).
5482 When generating relocateable output, the back end routine
5483 must handle STB_LOCAL/STT_SECTION symbols specially. The
5484 output symbol is going to be a section symbol
5485 corresponding to the output section, which will require
5486 the addend to be adjusted. */
5488 if (! (*relocate_section) (output_bfd, finfo->info,
5489 input_bfd, o, contents,
5490 internal_relocs,
5491 finfo->internal_syms,
5492 finfo->sections))
5493 return false;
5495 if (finfo->info->relocateable || finfo->info->emitrelocations)
5497 Elf_Internal_Rela *irela;
5498 Elf_Internal_Rela *irelaend;
5499 struct elf_link_hash_entry **rel_hash;
5500 Elf_Internal_Shdr *input_rel_hdr;
5502 /* Adjust the reloc addresses and symbol indices. */
5504 irela = internal_relocs;
5505 irelaend =
5506 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5507 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5508 + elf_section_data (o->output_section)->rel_count
5509 + elf_section_data (o->output_section)->rel_count2);
5510 for (; irela < irelaend; irela++, rel_hash++)
5512 unsigned long r_symndx;
5513 Elf_Internal_Sym *isym;
5514 asection *sec;
5516 irela->r_offset += o->output_offset;
5518 /* Relocs in an executable have to be virtual addresses. */
5519 if (finfo->info->emitrelocations)
5520 irela->r_offset += o->output_section->vma;
5522 r_symndx = ELF_R_SYM (irela->r_info);
5524 if (r_symndx == 0)
5525 continue;
5527 if (r_symndx >= locsymcount
5528 || (elf_bad_symtab (input_bfd)
5529 && finfo->sections[r_symndx] == NULL))
5531 struct elf_link_hash_entry *rh;
5532 long indx;
5534 /* This is a reloc against a global symbol. We
5535 have not yet output all the local symbols, so
5536 we do not know the symbol index of any global
5537 symbol. We set the rel_hash entry for this
5538 reloc to point to the global hash table entry
5539 for this symbol. The symbol index is then
5540 set at the end of elf_bfd_final_link. */
5541 indx = r_symndx - extsymoff;
5542 rh = elf_sym_hashes (input_bfd)[indx];
5543 while (rh->root.type == bfd_link_hash_indirect
5544 || rh->root.type == bfd_link_hash_warning)
5545 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5547 /* Setting the index to -2 tells
5548 elf_link_output_extsym that this symbol is
5549 used by a reloc. */
5550 BFD_ASSERT (rh->indx < 0);
5551 rh->indx = -2;
5553 *rel_hash = rh;
5555 continue;
5558 /* This is a reloc against a local symbol. */
5560 *rel_hash = NULL;
5561 isym = finfo->internal_syms + r_symndx;
5562 sec = finfo->sections[r_symndx];
5563 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5565 /* I suppose the backend ought to fill in the
5566 section of any STT_SECTION symbol against a
5567 processor specific section. If we have
5568 discarded a section, the output_section will
5569 be the absolute section. */
5570 if (sec != NULL
5571 && (bfd_is_abs_section (sec)
5572 || (sec->output_section != NULL
5573 && bfd_is_abs_section (sec->output_section))))
5574 r_symndx = 0;
5575 else if (sec == NULL || sec->owner == NULL)
5577 bfd_set_error (bfd_error_bad_value);
5578 return false;
5580 else
5582 r_symndx = sec->output_section->target_index;
5583 BFD_ASSERT (r_symndx != 0);
5586 else
5588 if (finfo->indices[r_symndx] == -1)
5590 unsigned long link;
5591 const char *name;
5592 asection *osec;
5594 if (finfo->info->strip == strip_all)
5596 /* You can't do ld -r -s. */
5597 bfd_set_error (bfd_error_invalid_operation);
5598 return false;
5601 /* This symbol was skipped earlier, but
5602 since it is needed by a reloc, we
5603 must output it now. */
5604 link = symtab_hdr->sh_link;
5605 name = bfd_elf_string_from_elf_section (input_bfd,
5606 link,
5607 isym->st_name);
5608 if (name == NULL)
5609 return false;
5611 osec = sec->output_section;
5612 isym->st_shndx =
5613 _bfd_elf_section_from_bfd_section (output_bfd,
5614 osec);
5615 if (isym->st_shndx == (unsigned short) -1)
5616 return false;
5618 isym->st_value += sec->output_offset;
5619 if (! finfo->info->relocateable)
5620 isym->st_value += osec->vma;
5622 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5624 if (! elf_link_output_sym (finfo, name, isym, sec))
5625 return false;
5628 r_symndx = finfo->indices[r_symndx];
5631 irela->r_info = ELF_R_INFO (r_symndx,
5632 ELF_R_TYPE (irela->r_info));
5635 /* Swap out the relocs. */
5636 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5637 elf_link_output_relocs (output_bfd, o,
5638 input_rel_hdr,
5639 internal_relocs);
5640 internal_relocs
5641 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5642 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5643 if (input_rel_hdr)
5644 elf_link_output_relocs (output_bfd, o,
5645 input_rel_hdr,
5646 internal_relocs);
5650 /* Write out the modified section contents. */
5651 if (elf_section_data (o)->stab_info == NULL)
5653 if (! (o->flags & SEC_EXCLUDE) &&
5654 ! bfd_set_section_contents (output_bfd, o->output_section,
5655 contents, o->output_offset,
5656 (o->_cooked_size != 0
5657 ? o->_cooked_size
5658 : o->_raw_size)))
5659 return false;
5661 else
5663 if (! (_bfd_write_section_stabs
5664 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5665 o, &elf_section_data (o)->stab_info, contents)))
5666 return false;
5670 return true;
5673 /* Generate a reloc when linking an ELF file. This is a reloc
5674 requested by the linker, and does come from any input file. This
5675 is used to build constructor and destructor tables when linking
5676 with -Ur. */
5678 static boolean
5679 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5680 bfd *output_bfd;
5681 struct bfd_link_info *info;
5682 asection *output_section;
5683 struct bfd_link_order *link_order;
5685 reloc_howto_type *howto;
5686 long indx;
5687 bfd_vma offset;
5688 bfd_vma addend;
5689 struct elf_link_hash_entry **rel_hash_ptr;
5690 Elf_Internal_Shdr *rel_hdr;
5692 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5693 if (howto == NULL)
5695 bfd_set_error (bfd_error_bad_value);
5696 return false;
5699 addend = link_order->u.reloc.p->addend;
5701 /* Figure out the symbol index. */
5702 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5703 + elf_section_data (output_section)->rel_count
5704 + elf_section_data (output_section)->rel_count2);
5705 if (link_order->type == bfd_section_reloc_link_order)
5707 indx = link_order->u.reloc.p->u.section->target_index;
5708 BFD_ASSERT (indx != 0);
5709 *rel_hash_ptr = NULL;
5711 else
5713 struct elf_link_hash_entry *h;
5715 /* Treat a reloc against a defined symbol as though it were
5716 actually against the section. */
5717 h = ((struct elf_link_hash_entry *)
5718 bfd_wrapped_link_hash_lookup (output_bfd, info,
5719 link_order->u.reloc.p->u.name,
5720 false, false, true));
5721 if (h != NULL
5722 && (h->root.type == bfd_link_hash_defined
5723 || h->root.type == bfd_link_hash_defweak))
5725 asection *section;
5727 section = h->root.u.def.section;
5728 indx = section->output_section->target_index;
5729 *rel_hash_ptr = NULL;
5730 /* It seems that we ought to add the symbol value to the
5731 addend here, but in practice it has already been added
5732 because it was passed to constructor_callback. */
5733 addend += section->output_section->vma + section->output_offset;
5735 else if (h != NULL)
5737 /* Setting the index to -2 tells elf_link_output_extsym that
5738 this symbol is used by a reloc. */
5739 h->indx = -2;
5740 *rel_hash_ptr = h;
5741 indx = 0;
5743 else
5745 if (! ((*info->callbacks->unattached_reloc)
5746 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5747 (asection *) NULL, (bfd_vma) 0)))
5748 return false;
5749 indx = 0;
5753 /* If this is an inplace reloc, we must write the addend into the
5754 object file. */
5755 if (howto->partial_inplace && addend != 0)
5757 bfd_size_type size;
5758 bfd_reloc_status_type rstat;
5759 bfd_byte *buf;
5760 boolean ok;
5762 size = bfd_get_reloc_size (howto);
5763 buf = (bfd_byte *) bfd_zmalloc (size);
5764 if (buf == (bfd_byte *) NULL)
5765 return false;
5766 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5767 switch (rstat)
5769 case bfd_reloc_ok:
5770 break;
5771 default:
5772 case bfd_reloc_outofrange:
5773 abort ();
5774 case bfd_reloc_overflow:
5775 if (! ((*info->callbacks->reloc_overflow)
5776 (info,
5777 (link_order->type == bfd_section_reloc_link_order
5778 ? bfd_section_name (output_bfd,
5779 link_order->u.reloc.p->u.section)
5780 : link_order->u.reloc.p->u.name),
5781 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5782 (bfd_vma) 0)))
5784 free (buf);
5785 return false;
5787 break;
5789 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5790 (file_ptr) link_order->offset, size);
5791 free (buf);
5792 if (! ok)
5793 return false;
5796 /* The address of a reloc is relative to the section in a
5797 relocateable file, and is a virtual address in an executable
5798 file. */
5799 offset = link_order->offset;
5800 if (! info->relocateable)
5801 offset += output_section->vma;
5803 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5805 if (rel_hdr->sh_type == SHT_REL)
5807 Elf_Internal_Rel irel;
5808 Elf_External_Rel *erel;
5810 irel.r_offset = offset;
5811 irel.r_info = ELF_R_INFO (indx, howto->type);
5812 erel = ((Elf_External_Rel *) rel_hdr->contents
5813 + elf_section_data (output_section)->rel_count);
5814 elf_swap_reloc_out (output_bfd, &irel, erel);
5816 else
5818 Elf_Internal_Rela irela;
5819 Elf_External_Rela *erela;
5821 irela.r_offset = offset;
5822 irela.r_info = ELF_R_INFO (indx, howto->type);
5823 irela.r_addend = addend;
5824 erela = ((Elf_External_Rela *) rel_hdr->contents
5825 + elf_section_data (output_section)->rel_count);
5826 elf_swap_reloca_out (output_bfd, &irela, erela);
5829 ++elf_section_data (output_section)->rel_count;
5831 return true;
5835 /* Allocate a pointer to live in a linker created section. */
5837 boolean
5838 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5839 bfd *abfd;
5840 struct bfd_link_info *info;
5841 elf_linker_section_t *lsect;
5842 struct elf_link_hash_entry *h;
5843 const Elf_Internal_Rela *rel;
5845 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5846 elf_linker_section_pointers_t *linker_section_ptr;
5847 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5849 BFD_ASSERT (lsect != NULL);
5851 /* Is this a global symbol? */
5852 if (h != NULL)
5854 /* Has this symbol already been allocated, if so, our work is done */
5855 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5856 rel->r_addend,
5857 lsect->which))
5858 return true;
5860 ptr_linker_section_ptr = &h->linker_section_pointer;
5861 /* Make sure this symbol is output as a dynamic symbol. */
5862 if (h->dynindx == -1)
5864 if (! elf_link_record_dynamic_symbol (info, h))
5865 return false;
5868 if (lsect->rel_section)
5869 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5872 else /* Allocation of a pointer to a local symbol */
5874 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5876 /* Allocate a table to hold the local symbols if first time */
5877 if (!ptr)
5879 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5880 register unsigned int i;
5882 ptr = (elf_linker_section_pointers_t **)
5883 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5885 if (!ptr)
5886 return false;
5888 elf_local_ptr_offsets (abfd) = ptr;
5889 for (i = 0; i < num_symbols; i++)
5890 ptr[i] = (elf_linker_section_pointers_t *)0;
5893 /* Has this symbol already been allocated, if so, our work is done */
5894 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5895 rel->r_addend,
5896 lsect->which))
5897 return true;
5899 ptr_linker_section_ptr = &ptr[r_symndx];
5901 if (info->shared)
5903 /* If we are generating a shared object, we need to
5904 output a R_<xxx>_RELATIVE reloc so that the
5905 dynamic linker can adjust this GOT entry. */
5906 BFD_ASSERT (lsect->rel_section != NULL);
5907 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5911 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5912 from internal memory. */
5913 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5914 linker_section_ptr = (elf_linker_section_pointers_t *)
5915 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5917 if (!linker_section_ptr)
5918 return false;
5920 linker_section_ptr->next = *ptr_linker_section_ptr;
5921 linker_section_ptr->addend = rel->r_addend;
5922 linker_section_ptr->which = lsect->which;
5923 linker_section_ptr->written_address_p = false;
5924 *ptr_linker_section_ptr = linker_section_ptr;
5926 #if 0
5927 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5929 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5930 lsect->hole_offset += ARCH_SIZE / 8;
5931 lsect->sym_offset += ARCH_SIZE / 8;
5932 if (lsect->sym_hash) /* Bump up symbol value if needed */
5934 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5935 #ifdef DEBUG
5936 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5937 lsect->sym_hash->root.root.string,
5938 (long)ARCH_SIZE / 8,
5939 (long)lsect->sym_hash->root.u.def.value);
5940 #endif
5943 else
5944 #endif
5945 linker_section_ptr->offset = lsect->section->_raw_size;
5947 lsect->section->_raw_size += ARCH_SIZE / 8;
5949 #ifdef DEBUG
5950 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5951 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5952 #endif
5954 return true;
5958 #if ARCH_SIZE==64
5959 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5960 #endif
5961 #if ARCH_SIZE==32
5962 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5963 #endif
5965 /* Fill in the address for a pointer generated in alinker section. */
5967 bfd_vma
5968 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5969 bfd *output_bfd;
5970 bfd *input_bfd;
5971 struct bfd_link_info *info;
5972 elf_linker_section_t *lsect;
5973 struct elf_link_hash_entry *h;
5974 bfd_vma relocation;
5975 const Elf_Internal_Rela *rel;
5976 int relative_reloc;
5978 elf_linker_section_pointers_t *linker_section_ptr;
5980 BFD_ASSERT (lsect != NULL);
5982 if (h != NULL) /* global symbol */
5984 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5985 rel->r_addend,
5986 lsect->which);
5988 BFD_ASSERT (linker_section_ptr != NULL);
5990 if (! elf_hash_table (info)->dynamic_sections_created
5991 || (info->shared
5992 && info->symbolic
5993 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5995 /* This is actually a static link, or it is a
5996 -Bsymbolic link and the symbol is defined
5997 locally. We must initialize this entry in the
5998 global section.
6000 When doing a dynamic link, we create a .rela.<xxx>
6001 relocation entry to initialize the value. This
6002 is done in the finish_dynamic_symbol routine. */
6003 if (!linker_section_ptr->written_address_p)
6005 linker_section_ptr->written_address_p = true;
6006 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6007 lsect->section->contents + linker_section_ptr->offset);
6011 else /* local symbol */
6013 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6014 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6015 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6016 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6017 rel->r_addend,
6018 lsect->which);
6020 BFD_ASSERT (linker_section_ptr != NULL);
6022 /* Write out pointer if it hasn't been rewritten out before */
6023 if (!linker_section_ptr->written_address_p)
6025 linker_section_ptr->written_address_p = true;
6026 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6027 lsect->section->contents + linker_section_ptr->offset);
6029 if (info->shared)
6031 asection *srel = lsect->rel_section;
6032 Elf_Internal_Rela outrel;
6034 /* We need to generate a relative reloc for the dynamic linker. */
6035 if (!srel)
6036 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6037 lsect->rel_name);
6039 BFD_ASSERT (srel != NULL);
6041 outrel.r_offset = (lsect->section->output_section->vma
6042 + lsect->section->output_offset
6043 + linker_section_ptr->offset);
6044 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6045 outrel.r_addend = 0;
6046 elf_swap_reloca_out (output_bfd, &outrel,
6047 (((Elf_External_Rela *)
6048 lsect->section->contents)
6049 + elf_section_data (lsect->section)->rel_count));
6050 ++elf_section_data (lsect->section)->rel_count;
6055 relocation = (lsect->section->output_offset
6056 + linker_section_ptr->offset
6057 - lsect->hole_offset
6058 - lsect->sym_offset);
6060 #ifdef DEBUG
6061 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6062 lsect->name, (long)relocation, (long)relocation);
6063 #endif
6065 /* Subtract out the addend, because it will get added back in by the normal
6066 processing. */
6067 return relocation - linker_section_ptr->addend;
6070 /* Garbage collect unused sections. */
6072 static boolean elf_gc_mark
6073 PARAMS ((struct bfd_link_info *info, asection *sec,
6074 asection * (*gc_mark_hook)
6075 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6076 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6078 static boolean elf_gc_sweep
6079 PARAMS ((struct bfd_link_info *info,
6080 boolean (*gc_sweep_hook)
6081 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6082 const Elf_Internal_Rela *relocs))));
6084 static boolean elf_gc_sweep_symbol
6085 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6087 static boolean elf_gc_allocate_got_offsets
6088 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6090 static boolean elf_gc_propagate_vtable_entries_used
6091 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6093 static boolean elf_gc_smash_unused_vtentry_relocs
6094 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6096 /* The mark phase of garbage collection. For a given section, mark
6097 it, and all the sections which define symbols to which it refers. */
6099 static boolean
6100 elf_gc_mark (info, sec, gc_mark_hook)
6101 struct bfd_link_info *info;
6102 asection *sec;
6103 asection * (*gc_mark_hook)
6104 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6105 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6107 boolean ret = true;
6109 sec->gc_mark = 1;
6111 /* Look through the section relocs. */
6113 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6115 Elf_Internal_Rela *relstart, *rel, *relend;
6116 Elf_Internal_Shdr *symtab_hdr;
6117 struct elf_link_hash_entry **sym_hashes;
6118 size_t nlocsyms;
6119 size_t extsymoff;
6120 Elf_External_Sym *locsyms, *freesyms = NULL;
6121 bfd *input_bfd = sec->owner;
6122 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6124 /* GCFIXME: how to arrange so that relocs and symbols are not
6125 reread continually? */
6127 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6128 sym_hashes = elf_sym_hashes (input_bfd);
6130 /* Read the local symbols. */
6131 if (elf_bad_symtab (input_bfd))
6133 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6134 extsymoff = 0;
6136 else
6137 extsymoff = nlocsyms = symtab_hdr->sh_info;
6138 if (symtab_hdr->contents)
6139 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6140 else if (nlocsyms == 0)
6141 locsyms = NULL;
6142 else
6144 locsyms = freesyms =
6145 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6146 if (freesyms == NULL
6147 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6148 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6149 nlocsyms, input_bfd)
6150 != nlocsyms * sizeof (Elf_External_Sym)))
6152 ret = false;
6153 goto out1;
6157 /* Read the relocations. */
6158 relstart = (NAME(_bfd_elf,link_read_relocs)
6159 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6160 info->keep_memory));
6161 if (relstart == NULL)
6163 ret = false;
6164 goto out1;
6166 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6168 for (rel = relstart; rel < relend; rel++)
6170 unsigned long r_symndx;
6171 asection *rsec;
6172 struct elf_link_hash_entry *h;
6173 Elf_Internal_Sym s;
6175 r_symndx = ELF_R_SYM (rel->r_info);
6176 if (r_symndx == 0)
6177 continue;
6179 if (elf_bad_symtab (sec->owner))
6181 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6182 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6183 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6184 else
6186 h = sym_hashes[r_symndx - extsymoff];
6187 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6190 else if (r_symndx >= nlocsyms)
6192 h = sym_hashes[r_symndx - extsymoff];
6193 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6195 else
6197 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6198 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6201 if (rsec && !rsec->gc_mark)
6202 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6204 ret = false;
6205 goto out2;
6209 out2:
6210 if (!info->keep_memory)
6211 free (relstart);
6212 out1:
6213 if (freesyms)
6214 free (freesyms);
6217 return ret;
6220 /* The sweep phase of garbage collection. Remove all garbage sections. */
6222 static boolean
6223 elf_gc_sweep (info, gc_sweep_hook)
6224 struct bfd_link_info *info;
6225 boolean (*gc_sweep_hook)
6226 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6227 const Elf_Internal_Rela *relocs));
6229 bfd *sub;
6231 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6233 asection *o;
6235 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6236 continue;
6238 for (o = sub->sections; o != NULL; o = o->next)
6240 /* Keep special sections. Keep .debug sections. */
6241 if ((o->flags & SEC_LINKER_CREATED)
6242 || (o->flags & SEC_DEBUGGING))
6243 o->gc_mark = 1;
6245 if (o->gc_mark)
6246 continue;
6248 /* Skip sweeping sections already excluded. */
6249 if (o->flags & SEC_EXCLUDE)
6250 continue;
6252 /* Since this is early in the link process, it is simple
6253 to remove a section from the output. */
6254 o->flags |= SEC_EXCLUDE;
6256 /* But we also have to update some of the relocation
6257 info we collected before. */
6258 if (gc_sweep_hook
6259 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6261 Elf_Internal_Rela *internal_relocs;
6262 boolean r;
6264 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6265 (o->owner, o, NULL, NULL, info->keep_memory));
6266 if (internal_relocs == NULL)
6267 return false;
6269 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6271 if (!info->keep_memory)
6272 free (internal_relocs);
6274 if (!r)
6275 return false;
6280 /* Remove the symbols that were in the swept sections from the dynamic
6281 symbol table. GCFIXME: Anyone know how to get them out of the
6282 static symbol table as well? */
6284 int i = 0;
6286 elf_link_hash_traverse (elf_hash_table (info),
6287 elf_gc_sweep_symbol,
6288 (PTR) &i);
6290 elf_hash_table (info)->dynsymcount = i;
6293 return true;
6296 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6298 static boolean
6299 elf_gc_sweep_symbol (h, idxptr)
6300 struct elf_link_hash_entry *h;
6301 PTR idxptr;
6303 int *idx = (int *) idxptr;
6305 if (h->dynindx != -1
6306 && ((h->root.type != bfd_link_hash_defined
6307 && h->root.type != bfd_link_hash_defweak)
6308 || h->root.u.def.section->gc_mark))
6309 h->dynindx = (*idx)++;
6311 return true;
6314 /* Propogate collected vtable information. This is called through
6315 elf_link_hash_traverse. */
6317 static boolean
6318 elf_gc_propagate_vtable_entries_used (h, okp)
6319 struct elf_link_hash_entry *h;
6320 PTR okp;
6322 /* Those that are not vtables. */
6323 if (h->vtable_parent == NULL)
6324 return true;
6326 /* Those vtables that do not have parents, we cannot merge. */
6327 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6328 return true;
6330 /* If we've already been done, exit. */
6331 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6332 return true;
6334 /* Make sure the parent's table is up to date. */
6335 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6337 if (h->vtable_entries_used == NULL)
6339 /* None of this table's entries were referenced. Re-use the
6340 parent's table. */
6341 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6342 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6344 else
6346 size_t n;
6347 boolean *cu, *pu;
6349 /* Or the parent's entries into ours. */
6350 cu = h->vtable_entries_used;
6351 cu[-1] = true;
6352 pu = h->vtable_parent->vtable_entries_used;
6353 if (pu != NULL)
6355 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6356 while (--n != 0)
6358 if (*pu) *cu = true;
6359 pu++, cu++;
6364 return true;
6367 static boolean
6368 elf_gc_smash_unused_vtentry_relocs (h, okp)
6369 struct elf_link_hash_entry *h;
6370 PTR okp;
6372 asection *sec;
6373 bfd_vma hstart, hend;
6374 Elf_Internal_Rela *relstart, *relend, *rel;
6375 struct elf_backend_data *bed;
6377 /* Take care of both those symbols that do not describe vtables as
6378 well as those that are not loaded. */
6379 if (h->vtable_parent == NULL)
6380 return true;
6382 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6383 || h->root.type == bfd_link_hash_defweak);
6385 sec = h->root.u.def.section;
6386 hstart = h->root.u.def.value;
6387 hend = hstart + h->size;
6389 relstart = (NAME(_bfd_elf,link_read_relocs)
6390 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6391 if (!relstart)
6392 return *(boolean *)okp = false;
6393 bed = get_elf_backend_data (sec->owner);
6394 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6396 for (rel = relstart; rel < relend; ++rel)
6397 if (rel->r_offset >= hstart && rel->r_offset < hend)
6399 /* If the entry is in use, do nothing. */
6400 if (h->vtable_entries_used
6401 && (rel->r_offset - hstart) < h->vtable_entries_size)
6403 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6404 if (h->vtable_entries_used[entry])
6405 continue;
6407 /* Otherwise, kill it. */
6408 rel->r_offset = rel->r_info = rel->r_addend = 0;
6411 return true;
6414 /* Do mark and sweep of unused sections. */
6416 boolean
6417 elf_gc_sections (abfd, info)
6418 bfd *abfd;
6419 struct bfd_link_info *info;
6421 boolean ok = true;
6422 bfd *sub;
6423 asection * (*gc_mark_hook)
6424 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6425 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6427 if (!get_elf_backend_data (abfd)->can_gc_sections
6428 || info->relocateable || info->emitrelocations
6429 || elf_hash_table (info)->dynamic_sections_created)
6430 return true;
6432 /* Apply transitive closure to the vtable entry usage info. */
6433 elf_link_hash_traverse (elf_hash_table (info),
6434 elf_gc_propagate_vtable_entries_used,
6435 (PTR) &ok);
6436 if (!ok)
6437 return false;
6439 /* Kill the vtable relocations that were not used. */
6440 elf_link_hash_traverse (elf_hash_table (info),
6441 elf_gc_smash_unused_vtentry_relocs,
6442 (PTR) &ok);
6443 if (!ok)
6444 return false;
6446 /* Grovel through relocs to find out who stays ... */
6448 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6449 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6451 asection *o;
6453 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6454 continue;
6456 for (o = sub->sections; o != NULL; o = o->next)
6458 if (o->flags & SEC_KEEP)
6459 if (!elf_gc_mark (info, o, gc_mark_hook))
6460 return false;
6464 /* ... and mark SEC_EXCLUDE for those that go. */
6465 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6466 return false;
6468 return true;
6471 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6473 boolean
6474 elf_gc_record_vtinherit (abfd, sec, h, offset)
6475 bfd *abfd;
6476 asection *sec;
6477 struct elf_link_hash_entry *h;
6478 bfd_vma offset;
6480 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6481 struct elf_link_hash_entry **search, *child;
6482 bfd_size_type extsymcount;
6484 /* The sh_info field of the symtab header tells us where the
6485 external symbols start. We don't care about the local symbols at
6486 this point. */
6487 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6488 if (!elf_bad_symtab (abfd))
6489 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6491 sym_hashes = elf_sym_hashes (abfd);
6492 sym_hashes_end = sym_hashes + extsymcount;
6494 /* Hunt down the child symbol, which is in this section at the same
6495 offset as the relocation. */
6496 for (search = sym_hashes; search != sym_hashes_end; ++search)
6498 if ((child = *search) != NULL
6499 && (child->root.type == bfd_link_hash_defined
6500 || child->root.type == bfd_link_hash_defweak)
6501 && child->root.u.def.section == sec
6502 && child->root.u.def.value == offset)
6503 goto win;
6506 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6507 bfd_get_filename (abfd), sec->name,
6508 (unsigned long)offset);
6509 bfd_set_error (bfd_error_invalid_operation);
6510 return false;
6512 win:
6513 if (!h)
6515 /* This *should* only be the absolute section. It could potentially
6516 be that someone has defined a non-global vtable though, which
6517 would be bad. It isn't worth paging in the local symbols to be
6518 sure though; that case should simply be handled by the assembler. */
6520 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6522 else
6523 child->vtable_parent = h;
6525 return true;
6528 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6530 boolean
6531 elf_gc_record_vtentry (abfd, sec, h, addend)
6532 bfd *abfd ATTRIBUTE_UNUSED;
6533 asection *sec ATTRIBUTE_UNUSED;
6534 struct elf_link_hash_entry *h;
6535 bfd_vma addend;
6537 if (addend >= h->vtable_entries_size)
6539 size_t size, bytes;
6540 boolean *ptr = h->vtable_entries_used;
6542 /* While the symbol is undefined, we have to be prepared to handle
6543 a zero size. */
6544 if (h->root.type == bfd_link_hash_undefined)
6545 size = addend;
6546 else
6548 size = h->size;
6549 if (size < addend)
6551 /* Oops! We've got a reference past the defined end of
6552 the table. This is probably a bug -- shall we warn? */
6553 size = addend;
6557 /* Allocate one extra entry for use as a "done" flag for the
6558 consolidation pass. */
6559 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6561 if (ptr)
6563 ptr = bfd_realloc (ptr - 1, bytes);
6565 if (ptr != NULL)
6567 size_t oldbytes;
6569 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6570 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6573 else
6574 ptr = bfd_zmalloc (bytes);
6576 if (ptr == NULL)
6577 return false;
6579 /* And arrange for that done flag to be at index -1. */
6580 h->vtable_entries_used = ptr + 1;
6581 h->vtable_entries_size = size;
6584 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6586 return true;
6589 /* And an accompanying bit to work out final got entry offsets once
6590 we're done. Should be called from final_link. */
6592 boolean
6593 elf_gc_common_finalize_got_offsets (abfd, info)
6594 bfd *abfd;
6595 struct bfd_link_info *info;
6597 bfd *i;
6598 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6599 bfd_vma gotoff;
6601 /* The GOT offset is relative to the .got section, but the GOT header is
6602 put into the .got.plt section, if the backend uses it. */
6603 if (bed->want_got_plt)
6604 gotoff = 0;
6605 else
6606 gotoff = bed->got_header_size;
6608 /* Do the local .got entries first. */
6609 for (i = info->input_bfds; i; i = i->link_next)
6611 bfd_signed_vma *local_got;
6612 bfd_size_type j, locsymcount;
6613 Elf_Internal_Shdr *symtab_hdr;
6615 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6616 continue;
6618 local_got = elf_local_got_refcounts (i);
6619 if (!local_got)
6620 continue;
6622 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6623 if (elf_bad_symtab (i))
6624 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6625 else
6626 locsymcount = symtab_hdr->sh_info;
6628 for (j = 0; j < locsymcount; ++j)
6630 if (local_got[j] > 0)
6632 local_got[j] = gotoff;
6633 gotoff += ARCH_SIZE / 8;
6635 else
6636 local_got[j] = (bfd_vma) -1;
6640 /* Then the global .got entries. .plt refcounts are handled by
6641 adjust_dynamic_symbol */
6642 elf_link_hash_traverse (elf_hash_table (info),
6643 elf_gc_allocate_got_offsets,
6644 (PTR) &gotoff);
6645 return true;
6648 /* We need a special top-level link routine to convert got reference counts
6649 to real got offsets. */
6651 static boolean
6652 elf_gc_allocate_got_offsets (h, offarg)
6653 struct elf_link_hash_entry *h;
6654 PTR offarg;
6656 bfd_vma *off = (bfd_vma *) offarg;
6658 if (h->got.refcount > 0)
6660 h->got.offset = off[0];
6661 off[0] += ARCH_SIZE / 8;
6663 else
6664 h->got.offset = (bfd_vma) -1;
6666 return true;
6669 /* Many folk need no more in the way of final link than this, once
6670 got entry reference counting is enabled. */
6672 boolean
6673 elf_gc_common_final_link (abfd, info)
6674 bfd *abfd;
6675 struct bfd_link_info *info;
6677 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6678 return false;
6680 /* Invoke the regular ELF backend linker to do all the work. */
6681 return elf_bfd_final_link (abfd, info);
6684 /* This function will be called though elf_link_hash_traverse to store
6685 all hash value of the exported symbols in an array. */
6687 static boolean
6688 elf_collect_hash_codes (h, data)
6689 struct elf_link_hash_entry *h;
6690 PTR data;
6692 unsigned long **valuep = (unsigned long **) data;
6693 const char *name;
6694 char *p;
6695 unsigned long ha;
6696 char *alc = NULL;
6698 /* Ignore indirect symbols. These are added by the versioning code. */
6699 if (h->dynindx == -1)
6700 return true;
6702 name = h->root.root.string;
6703 p = strchr (name, ELF_VER_CHR);
6704 if (p != NULL)
6706 alc = bfd_malloc (p - name + 1);
6707 memcpy (alc, name, p - name);
6708 alc[p - name] = '\0';
6709 name = alc;
6712 /* Compute the hash value. */
6713 ha = bfd_elf_hash (name);
6715 /* Store the found hash value in the array given as the argument. */
6716 *(*valuep)++ = ha;
6718 /* And store it in the struct so that we can put it in the hash table
6719 later. */
6720 h->elf_hash_value = ha;
6722 if (alc != NULL)
6723 free (alc);
6725 return true;