* configure.tgt (sparc64-*-linux-gnu*): Add elf32_sparc into
[binutils.git] / bfd / elflink.h
blob9464ff2e1067ef18201a62b7a046bee5dadb8248
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 *, 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 non-function symbol. */
84 static boolean
85 is_global_data_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 /* Function symbols do not count. */
95 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
96 return false;
98 /* If the section is undefined, then so is the symbol. */
99 if (sym->st_shndx == SHN_UNDEF)
100 return false;
102 /* If the symbol is defined in the common section, then
103 it is a common definition and so does not count. */
104 if (sym->st_shndx == SHN_COMMON)
105 return false;
107 /* If the symbol is in a target specific section then we
108 must rely upon the backend to tell us what it is. */
109 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
110 /* FIXME - this function is not coded yet:
112 return _bfd_is_global_symbol_definition (abfd, sym);
114 Instead for now assume that the definition is not global,
115 Even if this is wrong, at least the linker will behave
116 in the same way that it used to do. */
117 return false;
119 return true;
122 /* Search the symbol table of the archive element of the archive ABFD
123 whoes archive map contains a mention of SYMDEF, and determine if
124 the symbol is defined in this element. */
125 static boolean
126 elf_link_is_defined_archive_symbol (abfd, symdef)
127 bfd * abfd;
128 carsym * symdef;
130 Elf_Internal_Shdr * hdr;
131 Elf_External_Sym * esym;
132 Elf_External_Sym * esymend;
133 Elf_External_Sym * buf = NULL;
134 size_t symcount;
135 size_t extsymcount;
136 size_t extsymoff;
137 boolean result = false;
139 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
140 if (abfd == (bfd *) NULL)
141 return false;
143 if (! bfd_check_format (abfd, bfd_object))
144 return false;
146 /* If we have already included the element containing this symbol in the
147 link then we do not need to include it again. Just claim that any symbol
148 it contains is not a definition, so that our caller will not decide to
149 (re)include this element. */
150 if (abfd->archive_pass)
151 return false;
153 /* Select the appropriate symbol table. */
154 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
155 hdr = &elf_tdata (abfd)->symtab_hdr;
156 else
157 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
159 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
161 /* The sh_info field of the symtab header tells us where the
162 external symbols start. We don't care about the local symbols. */
163 if (elf_bad_symtab (abfd))
165 extsymcount = symcount;
166 extsymoff = 0;
168 else
170 extsymcount = symcount - hdr->sh_info;
171 extsymoff = hdr->sh_info;
174 buf = ((Elf_External_Sym *)
175 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
176 if (buf == NULL && extsymcount != 0)
177 return false;
179 /* Read in the symbol table.
180 FIXME: This ought to be cached somewhere. */
181 if (bfd_seek (abfd,
182 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
183 SEEK_SET) != 0
184 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
185 != extsymcount * sizeof (Elf_External_Sym)))
187 free (buf);
188 return false;
191 /* Scan the symbol table looking for SYMDEF. */
192 esymend = buf + extsymcount;
193 for (esym = buf;
194 esym < esymend;
195 esym++)
197 Elf_Internal_Sym sym;
198 const char * name;
200 elf_swap_symbol_in (abfd, esym, & sym);
202 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
203 if (name == (const char *) NULL)
204 break;
206 if (strcmp (name, symdef->name) == 0)
208 result = is_global_data_symbol_definition (abfd, & sym);
209 break;
213 free (buf);
215 return result;
218 /* Add symbols from an ELF archive file to the linker hash table. We
219 don't use _bfd_generic_link_add_archive_symbols because of a
220 problem which arises on UnixWare. The UnixWare libc.so is an
221 archive which includes an entry libc.so.1 which defines a bunch of
222 symbols. The libc.so archive also includes a number of other
223 object files, which also define symbols, some of which are the same
224 as those defined in libc.so.1. Correct linking requires that we
225 consider each object file in turn, and include it if it defines any
226 symbols we need. _bfd_generic_link_add_archive_symbols does not do
227 this; it looks through the list of undefined symbols, and includes
228 any object file which defines them. When this algorithm is used on
229 UnixWare, it winds up pulling in libc.so.1 early and defining a
230 bunch of symbols. This means that some of the other objects in the
231 archive are not included in the link, which is incorrect since they
232 precede libc.so.1 in the archive.
234 Fortunately, ELF archive handling is simpler than that done by
235 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
236 oddities. In ELF, if we find a symbol in the archive map, and the
237 symbol is currently undefined, we know that we must pull in that
238 object file.
240 Unfortunately, we do have to make multiple passes over the symbol
241 table until nothing further is resolved. */
243 static boolean
244 elf_link_add_archive_symbols (abfd, info)
245 bfd *abfd;
246 struct bfd_link_info *info;
248 symindex c;
249 boolean *defined = NULL;
250 boolean *included = NULL;
251 carsym *symdefs;
252 boolean loop;
254 if (! bfd_has_map (abfd))
256 /* An empty archive is a special case. */
257 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
258 return true;
259 bfd_set_error (bfd_error_no_armap);
260 return false;
263 /* Keep track of all symbols we know to be already defined, and all
264 files we know to be already included. This is to speed up the
265 second and subsequent passes. */
266 c = bfd_ardata (abfd)->symdef_count;
267 if (c == 0)
268 return true;
269 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
270 included = (boolean *) bfd_malloc (c * sizeof (boolean));
271 if (defined == (boolean *) NULL || included == (boolean *) NULL)
272 goto error_return;
273 memset (defined, 0, c * sizeof (boolean));
274 memset (included, 0, c * sizeof (boolean));
276 symdefs = bfd_ardata (abfd)->symdefs;
280 file_ptr last;
281 symindex i;
282 carsym *symdef;
283 carsym *symdefend;
285 loop = false;
286 last = -1;
288 symdef = symdefs;
289 symdefend = symdef + c;
290 for (i = 0; symdef < symdefend; symdef++, i++)
292 struct elf_link_hash_entry *h;
293 bfd *element;
294 struct bfd_link_hash_entry *undefs_tail;
295 symindex mark;
297 if (defined[i] || included[i])
298 continue;
299 if (symdef->file_offset == last)
301 included[i] = true;
302 continue;
305 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
306 false, false, false);
308 if (h == NULL)
310 char *p, *copy;
312 /* If this is a default version (the name contains @@),
313 look up the symbol again without the version. The
314 effect is that references to the symbol without the
315 version will be matched by the default symbol in the
316 archive. */
318 p = strchr (symdef->name, ELF_VER_CHR);
319 if (p == NULL || p[1] != ELF_VER_CHR)
320 continue;
322 copy = bfd_alloc (abfd, p - symdef->name + 1);
323 if (copy == NULL)
324 goto error_return;
325 memcpy (copy, symdef->name, p - symdef->name);
326 copy[p - symdef->name] = '\0';
328 h = elf_link_hash_lookup (elf_hash_table (info), copy,
329 false, false, false);
331 bfd_release (abfd, copy);
334 if (h == NULL)
335 continue;
337 if (h->root.type == bfd_link_hash_common)
339 /* We currently have a common symbol. The archive map contains
340 a reference to this symbol, so we may want to include it. We
341 only want to include it however, if this archive element
342 contains a definition of the symbol, not just another common
343 declaration of it.
345 Unfortunately some archivers (including GNU ar) will put
346 declarations of common symbols into their archive maps, as
347 well as real definitions, so we cannot just go by the archive
348 map alone. Instead we must read in the element's symbol
349 table and check that to see what kind of symbol definition
350 this is. */
351 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
352 continue;
354 else if (h->root.type != bfd_link_hash_undefined)
356 if (h->root.type != bfd_link_hash_undefweak)
357 defined[i] = true;
358 continue;
361 /* We need to include this archive member. */
362 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
363 if (element == (bfd *) NULL)
364 goto error_return;
366 if (! bfd_check_format (element, bfd_object))
367 goto error_return;
369 /* Doublecheck that we have not included this object
370 already--it should be impossible, but there may be
371 something wrong with the archive. */
372 if (element->archive_pass != 0)
374 bfd_set_error (bfd_error_bad_value);
375 goto error_return;
377 element->archive_pass = 1;
379 undefs_tail = info->hash->undefs_tail;
381 if (! (*info->callbacks->add_archive_element) (info, element,
382 symdef->name))
383 goto error_return;
384 if (! elf_link_add_object_symbols (element, info))
385 goto error_return;
387 /* If there are any new undefined symbols, we need to make
388 another pass through the archive in order to see whether
389 they can be defined. FIXME: This isn't perfect, because
390 common symbols wind up on undefs_tail and because an
391 undefined symbol which is defined later on in this pass
392 does not require another pass. This isn't a bug, but it
393 does make the code less efficient than it could be. */
394 if (undefs_tail != info->hash->undefs_tail)
395 loop = true;
397 /* Look backward to mark all symbols from this object file
398 which we have already seen in this pass. */
399 mark = i;
402 included[mark] = true;
403 if (mark == 0)
404 break;
405 --mark;
407 while (symdefs[mark].file_offset == symdef->file_offset);
409 /* We mark subsequent symbols from this object file as we go
410 on through the loop. */
411 last = symdef->file_offset;
414 while (loop);
416 free (defined);
417 free (included);
419 return true;
421 error_return:
422 if (defined != (boolean *) NULL)
423 free (defined);
424 if (included != (boolean *) NULL)
425 free (included);
426 return false;
429 /* This function is called when we want to define a new symbol. It
430 handles the various cases which arise when we find a definition in
431 a dynamic object, or when there is already a definition in a
432 dynamic object. The new symbol is described by NAME, SYM, PSEC,
433 and PVALUE. We set SYM_HASH to the hash table entry. We set
434 OVERRIDE if the old symbol is overriding a new definition. We set
435 TYPE_CHANGE_OK if it is OK for the type to change. We set
436 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
437 change, we mean that we shouldn't warn if the type or size does
438 change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
439 a shared object. */
441 static boolean
442 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
443 override, type_change_ok, size_change_ok, dt_needed)
444 bfd *abfd;
445 struct bfd_link_info *info;
446 const char *name;
447 Elf_Internal_Sym *sym;
448 asection **psec;
449 bfd_vma *pvalue;
450 struct elf_link_hash_entry **sym_hash;
451 boolean *override;
452 boolean *type_change_ok;
453 boolean *size_change_ok;
454 boolean dt_needed;
456 asection *sec;
457 struct elf_link_hash_entry *h;
458 int bind;
459 bfd *oldbfd;
460 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
462 *override = false;
464 sec = *psec;
465 bind = ELF_ST_BIND (sym->st_info);
467 if (! bfd_is_und_section (sec))
468 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
469 else
470 h = ((struct elf_link_hash_entry *)
471 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
472 if (h == NULL)
473 return false;
474 *sym_hash = h;
476 /* This code is for coping with dynamic objects, and is only useful
477 if we are doing an ELF link. */
478 if (info->hash->creator != abfd->xvec)
479 return true;
481 /* For merging, we only care about real symbols. */
483 while (h->root.type == bfd_link_hash_indirect
484 || h->root.type == bfd_link_hash_warning)
485 h = (struct elf_link_hash_entry *) h->root.u.i.link;
487 /* If we just created the symbol, mark it as being an ELF symbol.
488 Other than that, there is nothing to do--there is no merge issue
489 with a newly defined symbol--so we just return. */
491 if (h->root.type == bfd_link_hash_new)
493 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
494 return true;
497 /* OLDBFD is a BFD associated with the existing symbol. */
499 switch (h->root.type)
501 default:
502 oldbfd = NULL;
503 break;
505 case bfd_link_hash_undefined:
506 case bfd_link_hash_undefweak:
507 oldbfd = h->root.u.undef.abfd;
508 break;
510 case bfd_link_hash_defined:
511 case bfd_link_hash_defweak:
512 oldbfd = h->root.u.def.section->owner;
513 break;
515 case bfd_link_hash_common:
516 oldbfd = h->root.u.c.p->section->owner;
517 break;
520 /* In cases involving weak versioned symbols, we may wind up trying
521 to merge a symbol with itself. Catch that here, to avoid the
522 confusion that results if we try to override a symbol with
523 itself. The additional tests catch cases like
524 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
525 dynamic object, which we do want to handle here. */
526 if (abfd == oldbfd
527 && ((abfd->flags & DYNAMIC) == 0
528 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
529 return true;
531 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
532 respectively, is from a dynamic object. */
534 if ((abfd->flags & DYNAMIC) != 0)
535 newdyn = true;
536 else
537 newdyn = false;
539 if (oldbfd != NULL)
540 olddyn = (oldbfd->flags & DYNAMIC) != 0;
541 else
543 asection *hsec;
545 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
546 indices used by MIPS ELF. */
547 switch (h->root.type)
549 default:
550 hsec = NULL;
551 break;
553 case bfd_link_hash_defined:
554 case bfd_link_hash_defweak:
555 hsec = h->root.u.def.section;
556 break;
558 case bfd_link_hash_common:
559 hsec = h->root.u.c.p->section;
560 break;
563 if (hsec == NULL)
564 olddyn = false;
565 else
566 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
569 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
570 respectively, appear to be a definition rather than reference. */
572 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
573 newdef = false;
574 else
575 newdef = true;
577 if (h->root.type == bfd_link_hash_undefined
578 || h->root.type == bfd_link_hash_undefweak
579 || h->root.type == bfd_link_hash_common)
580 olddef = false;
581 else
582 olddef = true;
584 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
585 symbol, respectively, appears to be a common symbol in a dynamic
586 object. If a symbol appears in an uninitialized section, and is
587 not weak, and is not a function, then it may be a common symbol
588 which was resolved when the dynamic object was created. We want
589 to treat such symbols specially, because they raise special
590 considerations when setting the symbol size: if the symbol
591 appears as a common symbol in a regular object, and the size in
592 the regular object is larger, we must make sure that we use the
593 larger size. This problematic case can always be avoided in C,
594 but it must be handled correctly when using Fortran shared
595 libraries.
597 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
598 likewise for OLDDYNCOMMON and OLDDEF.
600 Note that this test is just a heuristic, and that it is quite
601 possible to have an uninitialized symbol in a shared object which
602 is really a definition, rather than a common symbol. This could
603 lead to some minor confusion when the symbol really is a common
604 symbol in some regular object. However, I think it will be
605 harmless. */
607 if (newdyn
608 && newdef
609 && (sec->flags & SEC_ALLOC) != 0
610 && (sec->flags & SEC_LOAD) == 0
611 && sym->st_size > 0
612 && bind != STB_WEAK
613 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
614 newdyncommon = true;
615 else
616 newdyncommon = false;
618 if (olddyn
619 && olddef
620 && h->root.type == bfd_link_hash_defined
621 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
622 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
623 && (h->root.u.def.section->flags & SEC_LOAD) == 0
624 && h->size > 0
625 && h->type != STT_FUNC)
626 olddyncommon = true;
627 else
628 olddyncommon = false;
630 /* It's OK to change the type if either the existing symbol or the
631 new symbol is weak unless it comes from a DT_NEEDED entry of
632 a shared object, in which case, the DT_NEEDED entry may not be
633 required at the run time. */
635 if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
636 || h->root.type == bfd_link_hash_undefweak
637 || bind == STB_WEAK)
638 *type_change_ok = true;
640 /* It's OK to change the size if either the existing symbol or the
641 new symbol is weak, or if the old symbol is undefined. */
643 if (*type_change_ok
644 || h->root.type == bfd_link_hash_undefined)
645 *size_change_ok = true;
647 /* If both the old and the new symbols look like common symbols in a
648 dynamic object, set the size of the symbol to the larger of the
649 two. */
651 if (olddyncommon
652 && newdyncommon
653 && sym->st_size != h->size)
655 /* Since we think we have two common symbols, issue a multiple
656 common warning if desired. Note that we only warn if the
657 size is different. If the size is the same, we simply let
658 the old symbol override the new one as normally happens with
659 symbols defined in dynamic objects. */
661 if (! ((*info->callbacks->multiple_common)
662 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
663 h->size, abfd, bfd_link_hash_common, sym->st_size)))
664 return false;
666 if (sym->st_size > h->size)
667 h->size = sym->st_size;
669 *size_change_ok = true;
672 /* If we are looking at a dynamic object, and we have found a
673 definition, we need to see if the symbol was already defined by
674 some other object. If so, we want to use the existing
675 definition, and we do not want to report a multiple symbol
676 definition error; we do this by clobbering *PSEC to be
677 bfd_und_section_ptr.
679 We treat a common symbol as a definition if the symbol in the
680 shared library is a function, since common symbols always
681 represent variables; this can cause confusion in principle, but
682 any such confusion would seem to indicate an erroneous program or
683 shared library. We also permit a common symbol in a regular
684 object to override a weak symbol in a shared object.
686 We prefer a non-weak definition in a shared library to a weak
687 definition in the executable unless it comes from a DT_NEEDED
688 entry of a shared object, in which case, the DT_NEEDED entry
689 may not be required at the run time. */
691 if (newdyn
692 && newdef
693 && (olddef
694 || (h->root.type == bfd_link_hash_common
695 && (bind == STB_WEAK
696 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
697 && (h->root.type != bfd_link_hash_defweak
698 || dt_needed
699 || bind == STB_WEAK))
701 *override = true;
702 newdef = false;
703 newdyncommon = false;
705 *psec = sec = bfd_und_section_ptr;
706 *size_change_ok = true;
708 /* If we get here when the old symbol is a common symbol, then
709 we are explicitly letting it override a weak symbol or
710 function in a dynamic object, and we don't want to warn about
711 a type change. If the old symbol is a defined symbol, a type
712 change warning may still be appropriate. */
714 if (h->root.type == bfd_link_hash_common)
715 *type_change_ok = true;
718 /* Handle the special case of an old common symbol merging with a
719 new symbol which looks like a common symbol in a shared object.
720 We change *PSEC and *PVALUE to make the new symbol look like a
721 common symbol, and let _bfd_generic_link_add_one_symbol will do
722 the right thing. */
724 if (newdyncommon
725 && h->root.type == bfd_link_hash_common)
727 *override = true;
728 newdef = false;
729 newdyncommon = false;
730 *pvalue = sym->st_size;
731 *psec = sec = bfd_com_section_ptr;
732 *size_change_ok = true;
735 /* If the old symbol is from a dynamic object, and the new symbol is
736 a definition which is not from a dynamic object, then the new
737 symbol overrides the old symbol. Symbols from regular files
738 always take precedence over symbols from dynamic objects, even if
739 they are defined after the dynamic object in the link.
741 As above, we again permit a common symbol in a regular object to
742 override a definition in a shared object if the shared object
743 symbol is a function or is weak.
745 As above, we permit a non-weak definition in a shared object to
746 override a weak definition in a regular object. */
748 if (! newdyn
749 && (newdef
750 || (bfd_is_com_section (sec)
751 && (h->root.type == bfd_link_hash_defweak
752 || h->type == STT_FUNC)))
753 && olddyn
754 && olddef
755 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
756 && (bind != STB_WEAK
757 || h->root.type == bfd_link_hash_defweak))
759 /* Change the hash table entry to undefined, and let
760 _bfd_generic_link_add_one_symbol do the right thing with the
761 new definition. */
763 h->root.type = bfd_link_hash_undefined;
764 h->root.u.undef.abfd = h->root.u.def.section->owner;
765 *size_change_ok = true;
767 olddef = false;
768 olddyncommon = false;
770 /* We again permit a type change when a common symbol may be
771 overriding a function. */
773 if (bfd_is_com_section (sec))
774 *type_change_ok = true;
776 /* This union may have been set to be non-NULL when this symbol
777 was seen in a dynamic object. We must force the union to be
778 NULL, so that it is correct for a regular symbol. */
780 h->verinfo.vertree = NULL;
782 /* In this special case, if H is the target of an indirection,
783 we want the caller to frob with H rather than with the
784 indirect symbol. That will permit the caller to redefine the
785 target of the indirection, rather than the indirect symbol
786 itself. FIXME: This will break the -y option if we store a
787 symbol with a different name. */
788 *sym_hash = h;
791 /* Handle the special case of a new common symbol merging with an
792 old symbol that looks like it might be a common symbol defined in
793 a shared object. Note that we have already handled the case in
794 which a new common symbol should simply override the definition
795 in the shared library. */
797 if (! newdyn
798 && bfd_is_com_section (sec)
799 && olddyncommon)
801 /* It would be best if we could set the hash table entry to a
802 common symbol, but we don't know what to use for the section
803 or the alignment. */
804 if (! ((*info->callbacks->multiple_common)
805 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
806 h->size, abfd, bfd_link_hash_common, sym->st_size)))
807 return false;
809 /* If the predumed common symbol in the dynamic object is
810 larger, pretend that the new symbol has its size. */
812 if (h->size > *pvalue)
813 *pvalue = h->size;
815 /* FIXME: We no longer know the alignment required by the symbol
816 in the dynamic object, so we just wind up using the one from
817 the regular object. */
819 olddef = false;
820 olddyncommon = false;
822 h->root.type = bfd_link_hash_undefined;
823 h->root.u.undef.abfd = h->root.u.def.section->owner;
825 *size_change_ok = true;
826 *type_change_ok = true;
828 h->verinfo.vertree = NULL;
831 /* Handle the special case of a weak definition in a regular object
832 followed by a non-weak definition in a shared object. In this
833 case, we prefer the definition in the shared object unless it
834 comes from a DT_NEEDED entry of a shared object, in which case,
835 the DT_NEEDED entry may not be required at the run time. */
836 if (olddef
837 && ! dt_needed
838 && h->root.type == bfd_link_hash_defweak
839 && newdef
840 && newdyn
841 && bind != STB_WEAK)
843 /* To make this work we have to frob the flags so that the rest
844 of the code does not think we are using the regular
845 definition. */
846 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
847 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
848 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
849 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
850 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
851 | ELF_LINK_HASH_DEF_DYNAMIC);
853 /* If H is the target of an indirection, we want the caller to
854 use H rather than the indirect symbol. Otherwise if we are
855 defining a new indirect symbol we will wind up attaching it
856 to the entry we are overriding. */
857 *sym_hash = h;
860 /* Handle the special case of a non-weak definition in a shared
861 object followed by a weak definition in a regular object. In
862 this case we prefer to definition in the shared object. To make
863 this work we have to tell the caller to not treat the new symbol
864 as a definition. */
865 if (olddef
866 && olddyn
867 && h->root.type != bfd_link_hash_defweak
868 && newdef
869 && ! newdyn
870 && bind == STB_WEAK)
871 *override = true;
873 return true;
876 /* Add symbols from an ELF object file to the linker hash table. */
878 static boolean
879 elf_link_add_object_symbols (abfd, info)
880 bfd *abfd;
881 struct bfd_link_info *info;
883 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
884 const Elf_Internal_Sym *,
885 const char **, flagword *,
886 asection **, bfd_vma *));
887 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
888 asection *, const Elf_Internal_Rela *));
889 boolean collect;
890 Elf_Internal_Shdr *hdr;
891 size_t symcount;
892 size_t extsymcount;
893 size_t extsymoff;
894 Elf_External_Sym *buf = NULL;
895 struct elf_link_hash_entry **sym_hash;
896 boolean dynamic;
897 bfd_byte *dynver = NULL;
898 Elf_External_Versym *extversym = NULL;
899 Elf_External_Versym *ever;
900 Elf_External_Dyn *dynbuf = NULL;
901 struct elf_link_hash_entry *weaks;
902 Elf_External_Sym *esym;
903 Elf_External_Sym *esymend;
904 struct elf_backend_data *bed;
905 boolean dt_needed;
907 bed = get_elf_backend_data (abfd);
908 add_symbol_hook = bed->elf_add_symbol_hook;
909 collect = bed->collect;
911 if ((abfd->flags & DYNAMIC) == 0)
912 dynamic = false;
913 else
915 dynamic = true;
917 /* You can't use -r against a dynamic object. Also, there's no
918 hope of using a dynamic object which does not exactly match
919 the format of the output file. */
920 if (info->relocateable || info->hash->creator != abfd->xvec)
922 bfd_set_error (bfd_error_invalid_operation);
923 goto error_return;
927 /* As a GNU extension, any input sections which are named
928 .gnu.warning.SYMBOL are treated as warning symbols for the given
929 symbol. This differs from .gnu.warning sections, which generate
930 warnings when they are included in an output file. */
931 if (! info->shared)
933 asection *s;
935 for (s = abfd->sections; s != NULL; s = s->next)
937 const char *name;
939 name = bfd_get_section_name (abfd, s);
940 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
942 char *msg;
943 bfd_size_type sz;
945 name += sizeof ".gnu.warning." - 1;
947 /* If this is a shared object, then look up the symbol
948 in the hash table. If it is there, and it is already
949 been defined, then we will not be using the entry
950 from this shared object, so we don't need to warn.
951 FIXME: If we see the definition in a regular object
952 later on, we will warn, but we shouldn't. The only
953 fix is to keep track of what warnings we are supposed
954 to emit, and then handle them all at the end of the
955 link. */
956 if (dynamic && abfd->xvec == info->hash->creator)
958 struct elf_link_hash_entry *h;
960 h = elf_link_hash_lookup (elf_hash_table (info), name,
961 false, false, true);
963 /* FIXME: What about bfd_link_hash_common? */
964 if (h != NULL
965 && (h->root.type == bfd_link_hash_defined
966 || h->root.type == bfd_link_hash_defweak))
968 /* We don't want to issue this warning. Clobber
969 the section size so that the warning does not
970 get copied into the output file. */
971 s->_raw_size = 0;
972 continue;
976 sz = bfd_section_size (abfd, s);
977 msg = (char *) bfd_alloc (abfd, sz + 1);
978 if (msg == NULL)
979 goto error_return;
981 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
982 goto error_return;
984 msg[sz] = '\0';
986 if (! (_bfd_generic_link_add_one_symbol
987 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
988 false, collect, (struct bfd_link_hash_entry **) NULL)))
989 goto error_return;
991 if (! info->relocateable)
993 /* Clobber the section size so that the warning does
994 not get copied into the output file. */
995 s->_raw_size = 0;
1001 /* If this is a dynamic object, we always link against the .dynsym
1002 symbol table, not the .symtab symbol table. The dynamic linker
1003 will only see the .dynsym symbol table, so there is no reason to
1004 look at .symtab for a dynamic object. */
1006 if (! dynamic || elf_dynsymtab (abfd) == 0)
1007 hdr = &elf_tdata (abfd)->symtab_hdr;
1008 else
1009 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1011 if (dynamic)
1013 /* Read in any version definitions. */
1015 if (! _bfd_elf_slurp_version_tables (abfd))
1016 goto error_return;
1018 /* Read in the symbol versions, but don't bother to convert them
1019 to internal format. */
1020 if (elf_dynversym (abfd) != 0)
1022 Elf_Internal_Shdr *versymhdr;
1024 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1025 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1026 if (extversym == NULL)
1027 goto error_return;
1028 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1029 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1030 != versymhdr->sh_size))
1031 goto error_return;
1035 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1037 /* The sh_info field of the symtab header tells us where the
1038 external symbols start. We don't care about the local symbols at
1039 this point. */
1040 if (elf_bad_symtab (abfd))
1042 extsymcount = symcount;
1043 extsymoff = 0;
1045 else
1047 extsymcount = symcount - hdr->sh_info;
1048 extsymoff = hdr->sh_info;
1051 buf = ((Elf_External_Sym *)
1052 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1053 if (buf == NULL && extsymcount != 0)
1054 goto error_return;
1056 /* We store a pointer to the hash table entry for each external
1057 symbol. */
1058 sym_hash = ((struct elf_link_hash_entry **)
1059 bfd_alloc (abfd,
1060 extsymcount * sizeof (struct elf_link_hash_entry *)));
1061 if (sym_hash == NULL)
1062 goto error_return;
1063 elf_sym_hashes (abfd) = sym_hash;
1065 dt_needed = false;
1067 if (! dynamic)
1069 /* If we are creating a shared library, create all the dynamic
1070 sections immediately. We need to attach them to something,
1071 so we attach them to this BFD, provided it is the right
1072 format. FIXME: If there are no input BFD's of the same
1073 format as the output, we can't make a shared library. */
1074 if (info->shared
1075 && ! elf_hash_table (info)->dynamic_sections_created
1076 && abfd->xvec == info->hash->creator)
1078 if (! elf_link_create_dynamic_sections (abfd, info))
1079 goto error_return;
1082 else
1084 asection *s;
1085 boolean add_needed;
1086 const char *name;
1087 bfd_size_type oldsize;
1088 bfd_size_type strindex;
1090 /* Find the name to use in a DT_NEEDED entry that refers to this
1091 object. If the object has a DT_SONAME entry, we use it.
1092 Otherwise, if the generic linker stuck something in
1093 elf_dt_name, we use that. Otherwise, we just use the file
1094 name. If the generic linker put a null string into
1095 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1096 there is a DT_SONAME entry. */
1097 add_needed = true;
1098 name = bfd_get_filename (abfd);
1099 if (elf_dt_name (abfd) != NULL)
1101 name = elf_dt_name (abfd);
1102 if (*name == '\0')
1104 if (elf_dt_soname (abfd) != NULL)
1105 dt_needed = true;
1107 add_needed = false;
1110 s = bfd_get_section_by_name (abfd, ".dynamic");
1111 if (s != NULL)
1113 Elf_External_Dyn *extdyn;
1114 Elf_External_Dyn *extdynend;
1115 int elfsec;
1116 unsigned long link;
1117 int rpath;
1118 int runpath;
1120 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1121 if (dynbuf == NULL)
1122 goto error_return;
1124 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1125 (file_ptr) 0, s->_raw_size))
1126 goto error_return;
1128 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1129 if (elfsec == -1)
1130 goto error_return;
1131 link = elf_elfsections (abfd)[elfsec]->sh_link;
1134 /* The shared libraries distributed with hpux11 have a bogus
1135 sh_link field for the ".dynamic" section. This code detects
1136 when LINK refers to a section that is not a string table and
1137 tries to find the string table for the ".dynsym" section
1138 instead. */
1139 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1140 if (hdr->sh_type != SHT_STRTAB)
1142 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1143 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1144 if (elfsec == -1)
1145 goto error_return;
1146 link = elf_elfsections (abfd)[elfsec]->sh_link;
1150 extdyn = dynbuf;
1151 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1152 rpath = 0;
1153 runpath = 0;
1154 for (; extdyn < extdynend; extdyn++)
1156 Elf_Internal_Dyn dyn;
1158 elf_swap_dyn_in (abfd, extdyn, &dyn);
1159 if (dyn.d_tag == DT_SONAME)
1161 name = bfd_elf_string_from_elf_section (abfd, link,
1162 dyn.d_un.d_val);
1163 if (name == NULL)
1164 goto error_return;
1166 if (dyn.d_tag == DT_NEEDED)
1168 struct bfd_link_needed_list *n, **pn;
1169 char *fnm, *anm;
1171 n = ((struct bfd_link_needed_list *)
1172 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1173 fnm = bfd_elf_string_from_elf_section (abfd, link,
1174 dyn.d_un.d_val);
1175 if (n == NULL || fnm == NULL)
1176 goto error_return;
1177 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1178 if (anm == NULL)
1179 goto error_return;
1180 strcpy (anm, fnm);
1181 n->name = anm;
1182 n->by = abfd;
1183 n->next = NULL;
1184 for (pn = &elf_hash_table (info)->needed;
1185 *pn != NULL;
1186 pn = &(*pn)->next)
1188 *pn = n;
1190 if (dyn.d_tag == DT_RUNPATH)
1192 struct bfd_link_needed_list *n, **pn;
1193 char *fnm, *anm;
1195 /* When we see DT_RPATH before DT_RUNPATH, we have
1196 to clear runpath. Do _NOT_ bfd_release, as that
1197 frees all more recently bfd_alloc'd blocks as
1198 well. */
1199 if (rpath && elf_hash_table (info)->runpath)
1200 elf_hash_table (info)->runpath = NULL;
1202 n = ((struct bfd_link_needed_list *)
1203 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1204 fnm = bfd_elf_string_from_elf_section (abfd, link,
1205 dyn.d_un.d_val);
1206 if (n == NULL || fnm == NULL)
1207 goto error_return;
1208 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1209 if (anm == NULL)
1210 goto error_return;
1211 strcpy (anm, fnm);
1212 n->name = anm;
1213 n->by = abfd;
1214 n->next = NULL;
1215 for (pn = &elf_hash_table (info)->runpath;
1216 *pn != NULL;
1217 pn = &(*pn)->next)
1219 *pn = n;
1220 runpath = 1;
1221 rpath = 0;
1223 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
1224 if (!runpath && dyn.d_tag == DT_RPATH)
1226 struct bfd_link_needed_list *n, **pn;
1227 char *fnm, *anm;
1229 n = ((struct bfd_link_needed_list *)
1230 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1231 fnm = bfd_elf_string_from_elf_section (abfd, link,
1232 dyn.d_un.d_val);
1233 if (n == NULL || fnm == NULL)
1234 goto error_return;
1235 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1236 if (anm == NULL)
1237 goto error_return;
1238 strcpy (anm, fnm);
1239 n->name = anm;
1240 n->by = abfd;
1241 n->next = NULL;
1242 for (pn = &elf_hash_table (info)->runpath;
1243 *pn != NULL;
1244 pn = &(*pn)->next)
1246 *pn = n;
1247 rpath = 1;
1251 free (dynbuf);
1252 dynbuf = NULL;
1255 /* We do not want to include any of the sections in a dynamic
1256 object in the output file. We hack by simply clobbering the
1257 list of sections in the BFD. This could be handled more
1258 cleanly by, say, a new section flag; the existing
1259 SEC_NEVER_LOAD flag is not the one we want, because that one
1260 still implies that the section takes up space in the output
1261 file. */
1262 abfd->sections = NULL;
1263 abfd->section_count = 0;
1265 /* If this is the first dynamic object found in the link, create
1266 the special sections required for dynamic linking. */
1267 if (! elf_hash_table (info)->dynamic_sections_created)
1269 if (! elf_link_create_dynamic_sections (abfd, info))
1270 goto error_return;
1273 if (add_needed)
1275 /* Add a DT_NEEDED entry for this dynamic object. */
1276 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1277 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1278 true, false);
1279 if (strindex == (bfd_size_type) -1)
1280 goto error_return;
1282 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1284 asection *sdyn;
1285 Elf_External_Dyn *dyncon, *dynconend;
1287 /* The hash table size did not change, which means that
1288 the dynamic object name was already entered. If we
1289 have already included this dynamic object in the
1290 link, just ignore it. There is no reason to include
1291 a particular dynamic object more than once. */
1292 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1293 ".dynamic");
1294 BFD_ASSERT (sdyn != NULL);
1296 dyncon = (Elf_External_Dyn *) sdyn->contents;
1297 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1298 sdyn->_raw_size);
1299 for (; dyncon < dynconend; dyncon++)
1301 Elf_Internal_Dyn dyn;
1303 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1304 &dyn);
1305 if (dyn.d_tag == DT_NEEDED
1306 && dyn.d_un.d_val == strindex)
1308 if (buf != NULL)
1309 free (buf);
1310 if (extversym != NULL)
1311 free (extversym);
1312 return true;
1317 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1318 goto error_return;
1321 /* Save the SONAME, if there is one, because sometimes the
1322 linker emulation code will need to know it. */
1323 if (*name == '\0')
1324 name = bfd_get_filename (abfd);
1325 elf_dt_name (abfd) = name;
1328 if (bfd_seek (abfd,
1329 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1330 SEEK_SET) != 0
1331 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1332 != extsymcount * sizeof (Elf_External_Sym)))
1333 goto error_return;
1335 weaks = NULL;
1337 ever = extversym != NULL ? extversym + extsymoff : NULL;
1338 esymend = buf + extsymcount;
1339 for (esym = buf;
1340 esym < esymend;
1341 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1343 Elf_Internal_Sym sym;
1344 int bind;
1345 bfd_vma value;
1346 asection *sec;
1347 flagword flags;
1348 const char *name;
1349 struct elf_link_hash_entry *h;
1350 boolean definition;
1351 boolean size_change_ok, type_change_ok;
1352 boolean new_weakdef;
1353 unsigned int old_alignment;
1355 elf_swap_symbol_in (abfd, esym, &sym);
1357 flags = BSF_NO_FLAGS;
1358 sec = NULL;
1359 value = sym.st_value;
1360 *sym_hash = NULL;
1362 bind = ELF_ST_BIND (sym.st_info);
1363 if (bind == STB_LOCAL)
1365 /* This should be impossible, since ELF requires that all
1366 global symbols follow all local symbols, and that sh_info
1367 point to the first global symbol. Unfortunatealy, Irix 5
1368 screws this up. */
1369 continue;
1371 else if (bind == STB_GLOBAL)
1373 if (sym.st_shndx != SHN_UNDEF
1374 && sym.st_shndx != SHN_COMMON)
1375 flags = BSF_GLOBAL;
1377 else if (bind == STB_WEAK)
1378 flags = BSF_WEAK;
1379 else
1381 /* Leave it up to the processor backend. */
1384 if (sym.st_shndx == SHN_UNDEF)
1385 sec = bfd_und_section_ptr;
1386 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1388 sec = section_from_elf_index (abfd, sym.st_shndx);
1389 if (sec == NULL)
1390 sec = bfd_abs_section_ptr;
1391 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1392 value -= sec->vma;
1394 else if (sym.st_shndx == SHN_ABS)
1395 sec = bfd_abs_section_ptr;
1396 else if (sym.st_shndx == SHN_COMMON)
1398 sec = bfd_com_section_ptr;
1399 /* What ELF calls the size we call the value. What ELF
1400 calls the value we call the alignment. */
1401 value = sym.st_size;
1403 else
1405 /* Leave it up to the processor backend. */
1408 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1409 if (name == (const char *) NULL)
1410 goto error_return;
1412 if (add_symbol_hook)
1414 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1415 &value))
1416 goto error_return;
1418 /* The hook function sets the name to NULL if this symbol
1419 should be skipped for some reason. */
1420 if (name == (const char *) NULL)
1421 continue;
1424 /* Sanity check that all possibilities were handled. */
1425 if (sec == (asection *) NULL)
1427 bfd_set_error (bfd_error_bad_value);
1428 goto error_return;
1431 if (bfd_is_und_section (sec)
1432 || bfd_is_com_section (sec))
1433 definition = false;
1434 else
1435 definition = true;
1437 size_change_ok = false;
1438 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1439 old_alignment = 0;
1440 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1442 Elf_Internal_Versym iver;
1443 unsigned int vernum = 0;
1444 boolean override;
1446 if (ever != NULL)
1448 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1449 vernum = iver.vs_vers & VERSYM_VERSION;
1451 /* If this is a hidden symbol, or if it is not version
1452 1, we append the version name to the symbol name.
1453 However, we do not modify a non-hidden absolute
1454 symbol, because it might be the version symbol
1455 itself. FIXME: What if it isn't? */
1456 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1457 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1459 const char *verstr;
1460 int namelen, newlen;
1461 char *newname, *p;
1463 if (sym.st_shndx != SHN_UNDEF)
1465 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1467 (*_bfd_error_handler)
1468 (_("%s: %s: invalid version %u (max %d)"),
1469 bfd_get_filename (abfd), name, vernum,
1470 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1471 bfd_set_error (bfd_error_bad_value);
1472 goto error_return;
1474 else if (vernum > 1)
1475 verstr =
1476 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1477 else
1478 verstr = "";
1480 else
1482 /* We cannot simply test for the number of
1483 entries in the VERNEED section since the
1484 numbers for the needed versions do not start
1485 at 0. */
1486 Elf_Internal_Verneed *t;
1488 verstr = NULL;
1489 for (t = elf_tdata (abfd)->verref;
1490 t != NULL;
1491 t = t->vn_nextref)
1493 Elf_Internal_Vernaux *a;
1495 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1497 if (a->vna_other == vernum)
1499 verstr = a->vna_nodename;
1500 break;
1503 if (a != NULL)
1504 break;
1506 if (verstr == NULL)
1508 (*_bfd_error_handler)
1509 (_("%s: %s: invalid needed version %d"),
1510 bfd_get_filename (abfd), name, vernum);
1511 bfd_set_error (bfd_error_bad_value);
1512 goto error_return;
1516 namelen = strlen (name);
1517 newlen = namelen + strlen (verstr) + 2;
1518 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1519 ++newlen;
1521 newname = (char *) bfd_alloc (abfd, newlen);
1522 if (newname == NULL)
1523 goto error_return;
1524 strcpy (newname, name);
1525 p = newname + namelen;
1526 *p++ = ELF_VER_CHR;
1527 /* If this is a defined non-hidden version symbol,
1528 we add another @ to the name. This indicates the
1529 default version of the symbol. */
1530 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1531 && sym.st_shndx != SHN_UNDEF)
1532 *p++ = ELF_VER_CHR;
1533 strcpy (p, verstr);
1535 name = newname;
1539 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1540 sym_hash, &override, &type_change_ok,
1541 &size_change_ok, dt_needed))
1542 goto error_return;
1544 if (override)
1545 definition = false;
1547 h = *sym_hash;
1548 while (h->root.type == bfd_link_hash_indirect
1549 || h->root.type == bfd_link_hash_warning)
1550 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1552 /* Remember the old alignment if this is a common symbol, so
1553 that we don't reduce the alignment later on. We can't
1554 check later, because _bfd_generic_link_add_one_symbol
1555 will set a default for the alignment which we want to
1556 override. */
1557 if (h->root.type == bfd_link_hash_common)
1558 old_alignment = h->root.u.c.p->alignment_power;
1560 if (elf_tdata (abfd)->verdef != NULL
1561 && ! override
1562 && vernum > 1
1563 && definition)
1564 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1567 if (! (_bfd_generic_link_add_one_symbol
1568 (info, abfd, name, flags, sec, value, (const char *) NULL,
1569 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1570 goto error_return;
1572 h = *sym_hash;
1573 while (h->root.type == bfd_link_hash_indirect
1574 || h->root.type == bfd_link_hash_warning)
1575 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1576 *sym_hash = h;
1578 new_weakdef = false;
1579 if (dynamic
1580 && definition
1581 && (flags & BSF_WEAK) != 0
1582 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1583 && info->hash->creator->flavour == bfd_target_elf_flavour
1584 && h->weakdef == NULL)
1586 /* Keep a list of all weak defined non function symbols from
1587 a dynamic object, using the weakdef field. Later in this
1588 function we will set the weakdef field to the correct
1589 value. We only put non-function symbols from dynamic
1590 objects on this list, because that happens to be the only
1591 time we need to know the normal symbol corresponding to a
1592 weak symbol, and the information is time consuming to
1593 figure out. If the weakdef field is not already NULL,
1594 then this symbol was already defined by some previous
1595 dynamic object, and we will be using that previous
1596 definition anyhow. */
1598 h->weakdef = weaks;
1599 weaks = h;
1600 new_weakdef = true;
1603 /* Set the alignment of a common symbol. */
1604 if (sym.st_shndx == SHN_COMMON
1605 && h->root.type == bfd_link_hash_common)
1607 unsigned int align;
1609 align = bfd_log2 (sym.st_value);
1610 if (align > old_alignment
1611 /* Permit an alignment power of zero if an alignment of one
1612 is specified and no other alignments have been specified. */
1613 || (sym.st_value == 1 && old_alignment == 0))
1614 h->root.u.c.p->alignment_power = align;
1617 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1619 int old_flags;
1620 boolean dynsym;
1621 int new_flag;
1623 /* Remember the symbol size and type. */
1624 if (sym.st_size != 0
1625 && (definition || h->size == 0))
1627 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1628 (*_bfd_error_handler)
1629 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1630 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1631 bfd_get_filename (abfd));
1633 h->size = sym.st_size;
1636 /* If this is a common symbol, then we always want H->SIZE
1637 to be the size of the common symbol. The code just above
1638 won't fix the size if a common symbol becomes larger. We
1639 don't warn about a size change here, because that is
1640 covered by --warn-common. */
1641 if (h->root.type == bfd_link_hash_common)
1642 h->size = h->root.u.c.size;
1644 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1645 && (definition || h->type == STT_NOTYPE))
1647 if (h->type != STT_NOTYPE
1648 && h->type != ELF_ST_TYPE (sym.st_info)
1649 && ! type_change_ok)
1650 (*_bfd_error_handler)
1651 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1652 name, h->type, ELF_ST_TYPE (sym.st_info),
1653 bfd_get_filename (abfd));
1655 h->type = ELF_ST_TYPE (sym.st_info);
1658 /* If st_other has a processor-specific meaning, specific code
1659 might be needed here. */
1660 if (sym.st_other != 0)
1662 /* Combine visibilities, using the most constraining one. */
1663 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1664 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1666 if (symvis && (hvis > symvis || hvis == 0))
1667 h->other = sym.st_other;
1669 /* If neither has visibility, use the st_other of the
1670 definition. This is an arbitrary choice, since the
1671 other bits have no general meaning. */
1672 if (!symvis && !hvis
1673 && (definition || h->other == 0))
1674 h->other = sym.st_other;
1677 /* Set a flag in the hash table entry indicating the type of
1678 reference or definition we just found. Keep a count of
1679 the number of dynamic symbols we find. A dynamic symbol
1680 is one which is referenced or defined by both a regular
1681 object and a shared object. */
1682 old_flags = h->elf_link_hash_flags;
1683 dynsym = false;
1684 if (! dynamic)
1686 if (! definition)
1688 new_flag = ELF_LINK_HASH_REF_REGULAR;
1689 if (bind != STB_WEAK)
1690 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1692 else
1693 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1694 if (info->shared
1695 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1696 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1697 dynsym = true;
1699 else
1701 if (! definition)
1702 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1703 else
1704 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1705 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1706 | ELF_LINK_HASH_REF_REGULAR)) != 0
1707 || (h->weakdef != NULL
1708 && ! new_weakdef
1709 && h->weakdef->dynindx != -1))
1710 dynsym = true;
1713 h->elf_link_hash_flags |= new_flag;
1715 /* If this symbol has a version, and it is the default
1716 version, we create an indirect symbol from the default
1717 name to the fully decorated name. This will cause
1718 external references which do not specify a version to be
1719 bound to this version of the symbol. */
1720 if (definition || h->root.type == bfd_link_hash_common)
1722 char *p;
1724 p = strchr (name, ELF_VER_CHR);
1725 if (p != NULL && p[1] == ELF_VER_CHR)
1727 char *shortname;
1728 struct elf_link_hash_entry *hi;
1729 boolean override;
1731 shortname = bfd_hash_allocate (&info->hash->table,
1732 p - name + 1);
1733 if (shortname == NULL)
1734 goto error_return;
1735 strncpy (shortname, name, p - name);
1736 shortname[p - name] = '\0';
1738 /* We are going to create a new symbol. Merge it
1739 with any existing symbol with this name. For the
1740 purposes of the merge, act as though we were
1741 defining the symbol we just defined, although we
1742 actually going to define an indirect symbol. */
1743 type_change_ok = false;
1744 size_change_ok = false;
1745 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1746 &value, &hi, &override,
1747 &type_change_ok,
1748 &size_change_ok, dt_needed))
1749 goto error_return;
1751 if (! override)
1753 if (! (_bfd_generic_link_add_one_symbol
1754 (info, abfd, shortname, BSF_INDIRECT,
1755 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1756 collect, (struct bfd_link_hash_entry **) &hi)))
1757 goto error_return;
1759 else
1761 /* In this case the symbol named SHORTNAME is
1762 overriding the indirect symbol we want to
1763 add. We were planning on making SHORTNAME an
1764 indirect symbol referring to NAME. SHORTNAME
1765 is the name without a version. NAME is the
1766 fully versioned name, and it is the default
1767 version.
1769 Overriding means that we already saw a
1770 definition for the symbol SHORTNAME in a
1771 regular object, and it is overriding the
1772 symbol defined in the dynamic object.
1774 When this happens, we actually want to change
1775 NAME, the symbol we just added, to refer to
1776 SHORTNAME. This will cause references to
1777 NAME in the shared object to become
1778 references to SHORTNAME in the regular
1779 object. This is what we expect when we
1780 override a function in a shared object: that
1781 the references in the shared object will be
1782 mapped to the definition in the regular
1783 object. */
1785 while (hi->root.type == bfd_link_hash_indirect
1786 || hi->root.type == bfd_link_hash_warning)
1787 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1789 h->root.type = bfd_link_hash_indirect;
1790 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1791 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1793 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1794 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1795 if (hi->elf_link_hash_flags
1796 & (ELF_LINK_HASH_REF_REGULAR
1797 | ELF_LINK_HASH_DEF_REGULAR))
1799 if (! _bfd_elf_link_record_dynamic_symbol (info,
1800 hi))
1801 goto error_return;
1805 /* Now set HI to H, so that the following code
1806 will set the other fields correctly. */
1807 hi = h;
1810 /* If there is a duplicate definition somewhere,
1811 then HI may not point to an indirect symbol. We
1812 will have reported an error to the user in that
1813 case. */
1815 if (hi->root.type == bfd_link_hash_indirect)
1817 struct elf_link_hash_entry *ht;
1819 /* If the symbol became indirect, then we assume
1820 that we have not seen a definition before. */
1821 BFD_ASSERT ((hi->elf_link_hash_flags
1822 & (ELF_LINK_HASH_DEF_DYNAMIC
1823 | ELF_LINK_HASH_DEF_REGULAR))
1824 == 0);
1826 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1827 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1829 /* See if the new flags lead us to realize that
1830 the symbol must be dynamic. */
1831 if (! dynsym)
1833 if (! dynamic)
1835 if (info->shared
1836 || ((hi->elf_link_hash_flags
1837 & ELF_LINK_HASH_REF_DYNAMIC)
1838 != 0))
1839 dynsym = true;
1841 else
1843 if ((hi->elf_link_hash_flags
1844 & ELF_LINK_HASH_REF_REGULAR) != 0)
1845 dynsym = true;
1850 /* We also need to define an indirection from the
1851 nondefault version of the symbol. */
1853 shortname = bfd_hash_allocate (&info->hash->table,
1854 strlen (name));
1855 if (shortname == NULL)
1856 goto error_return;
1857 strncpy (shortname, name, p - name);
1858 strcpy (shortname + (p - name), p + 1);
1860 /* Once again, merge with any existing symbol. */
1861 type_change_ok = false;
1862 size_change_ok = false;
1863 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1864 &value, &hi, &override,
1865 &type_change_ok,
1866 &size_change_ok, dt_needed))
1867 goto error_return;
1869 if (override)
1871 /* Here SHORTNAME is a versioned name, so we
1872 don't expect to see the type of override we
1873 do in the case above. */
1874 (*_bfd_error_handler)
1875 (_("%s: warning: unexpected redefinition of `%s'"),
1876 bfd_get_filename (abfd), shortname);
1878 else
1880 if (! (_bfd_generic_link_add_one_symbol
1881 (info, abfd, shortname, BSF_INDIRECT,
1882 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1883 collect, (struct bfd_link_hash_entry **) &hi)))
1884 goto error_return;
1886 /* If there is a duplicate definition somewhere,
1887 then HI may not point to an indirect symbol.
1888 We will have reported an error to the user in
1889 that case. */
1891 if (hi->root.type == bfd_link_hash_indirect)
1893 /* If the symbol became indirect, then we
1894 assume that we have not seen a definition
1895 before. */
1896 BFD_ASSERT ((hi->elf_link_hash_flags
1897 & (ELF_LINK_HASH_DEF_DYNAMIC
1898 | ELF_LINK_HASH_DEF_REGULAR))
1899 == 0);
1901 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1903 /* See if the new flags lead us to realize
1904 that the symbol must be dynamic. */
1905 if (! dynsym)
1907 if (! dynamic)
1909 if (info->shared
1910 || ((hi->elf_link_hash_flags
1911 & ELF_LINK_HASH_REF_DYNAMIC)
1912 != 0))
1913 dynsym = true;
1915 else
1917 if ((hi->elf_link_hash_flags
1918 & ELF_LINK_HASH_REF_REGULAR) != 0)
1919 dynsym = true;
1927 if (dynsym && h->dynindx == -1)
1929 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1930 goto error_return;
1931 if (h->weakdef != NULL
1932 && ! new_weakdef
1933 && h->weakdef->dynindx == -1)
1935 if (! _bfd_elf_link_record_dynamic_symbol (info,
1936 h->weakdef))
1937 goto error_return;
1940 else if (dynsym && h->dynindx != -1)
1941 /* If the symbol already has a dynamic index, but
1942 visibility says it should not be visible, turn it into
1943 a local symbol. */
1944 switch (ELF_ST_VISIBILITY (h->other))
1946 case STV_INTERNAL:
1947 case STV_HIDDEN:
1948 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1949 (*bed->elf_backend_hide_symbol) (info, h);
1950 break;
1953 if (dt_needed && definition
1954 && (h->elf_link_hash_flags
1955 & ELF_LINK_HASH_REF_REGULAR) != 0)
1957 bfd_size_type oldsize;
1958 bfd_size_type strindex;
1960 /* The symbol from a DT_NEEDED object is referenced from
1961 the regular object to create a dynamic executable. We
1962 have to make sure there is a DT_NEEDED entry for it. */
1964 dt_needed = false;
1965 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1966 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
1967 elf_dt_soname (abfd),
1968 true, false);
1969 if (strindex == (bfd_size_type) -1)
1970 goto error_return;
1972 if (oldsize
1973 == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1975 asection *sdyn;
1976 Elf_External_Dyn *dyncon, *dynconend;
1978 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1979 ".dynamic");
1980 BFD_ASSERT (sdyn != NULL);
1982 dyncon = (Elf_External_Dyn *) sdyn->contents;
1983 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1984 sdyn->_raw_size);
1985 for (; dyncon < dynconend; dyncon++)
1987 Elf_Internal_Dyn dyn;
1989 elf_swap_dyn_in (elf_hash_table (info)->dynobj,
1990 dyncon, &dyn);
1991 BFD_ASSERT (dyn.d_tag != DT_NEEDED ||
1992 dyn.d_un.d_val != strindex);
1996 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1997 goto error_return;
2002 /* Now set the weakdefs field correctly for all the weak defined
2003 symbols we found. The only way to do this is to search all the
2004 symbols. Since we only need the information for non functions in
2005 dynamic objects, that's the only time we actually put anything on
2006 the list WEAKS. We need this information so that if a regular
2007 object refers to a symbol defined weakly in a dynamic object, the
2008 real symbol in the dynamic object is also put in the dynamic
2009 symbols; we also must arrange for both symbols to point to the
2010 same memory location. We could handle the general case of symbol
2011 aliasing, but a general symbol alias can only be generated in
2012 assembler code, handling it correctly would be very time
2013 consuming, and other ELF linkers don't handle general aliasing
2014 either. */
2015 while (weaks != NULL)
2017 struct elf_link_hash_entry *hlook;
2018 asection *slook;
2019 bfd_vma vlook;
2020 struct elf_link_hash_entry **hpp;
2021 struct elf_link_hash_entry **hppend;
2023 hlook = weaks;
2024 weaks = hlook->weakdef;
2025 hlook->weakdef = NULL;
2027 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
2028 || hlook->root.type == bfd_link_hash_defweak
2029 || hlook->root.type == bfd_link_hash_common
2030 || hlook->root.type == bfd_link_hash_indirect);
2031 slook = hlook->root.u.def.section;
2032 vlook = hlook->root.u.def.value;
2034 hpp = elf_sym_hashes (abfd);
2035 hppend = hpp + extsymcount;
2036 for (; hpp < hppend; hpp++)
2038 struct elf_link_hash_entry *h;
2040 h = *hpp;
2041 if (h != NULL && h != hlook
2042 && h->root.type == bfd_link_hash_defined
2043 && h->root.u.def.section == slook
2044 && h->root.u.def.value == vlook)
2046 hlook->weakdef = h;
2048 /* If the weak definition is in the list of dynamic
2049 symbols, make sure the real definition is put there
2050 as well. */
2051 if (hlook->dynindx != -1
2052 && h->dynindx == -1)
2054 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2055 goto error_return;
2058 /* If the real definition is in the list of dynamic
2059 symbols, make sure the weak definition is put there
2060 as well. If we don't do this, then the dynamic
2061 loader might not merge the entries for the real
2062 definition and the weak definition. */
2063 if (h->dynindx != -1
2064 && hlook->dynindx == -1)
2066 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
2067 goto error_return;
2070 break;
2075 if (buf != NULL)
2077 free (buf);
2078 buf = NULL;
2081 if (extversym != NULL)
2083 free (extversym);
2084 extversym = NULL;
2087 /* If this object is the same format as the output object, and it is
2088 not a shared library, then let the backend look through the
2089 relocs.
2091 This is required to build global offset table entries and to
2092 arrange for dynamic relocs. It is not required for the
2093 particular common case of linking non PIC code, even when linking
2094 against shared libraries, but unfortunately there is no way of
2095 knowing whether an object file has been compiled PIC or not.
2096 Looking through the relocs is not particularly time consuming.
2097 The problem is that we must either (1) keep the relocs in memory,
2098 which causes the linker to require additional runtime memory or
2099 (2) read the relocs twice from the input file, which wastes time.
2100 This would be a good case for using mmap.
2102 I have no idea how to handle linking PIC code into a file of a
2103 different format. It probably can't be done. */
2104 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2105 if (! dynamic
2106 && abfd->xvec == info->hash->creator
2107 && check_relocs != NULL)
2109 asection *o;
2111 for (o = abfd->sections; o != NULL; o = o->next)
2113 Elf_Internal_Rela *internal_relocs;
2114 boolean ok;
2116 if ((o->flags & SEC_RELOC) == 0
2117 || o->reloc_count == 0
2118 || ((info->strip == strip_all || info->strip == strip_debugger)
2119 && (o->flags & SEC_DEBUGGING) != 0)
2120 || bfd_is_abs_section (o->output_section))
2121 continue;
2123 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2124 (abfd, o, (PTR) NULL,
2125 (Elf_Internal_Rela *) NULL,
2126 info->keep_memory));
2127 if (internal_relocs == NULL)
2128 goto error_return;
2130 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2132 if (! info->keep_memory)
2133 free (internal_relocs);
2135 if (! ok)
2136 goto error_return;
2140 /* If this is a non-traditional, non-relocateable link, try to
2141 optimize the handling of the .stab/.stabstr sections. */
2142 if (! dynamic
2143 && ! info->relocateable
2144 && ! info->traditional_format
2145 && info->hash->creator->flavour == bfd_target_elf_flavour
2146 && (info->strip != strip_all && info->strip != strip_debugger))
2148 asection *stab, *stabstr;
2150 stab = bfd_get_section_by_name (abfd, ".stab");
2151 if (stab != NULL)
2153 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2155 if (stabstr != NULL)
2157 struct bfd_elf_section_data *secdata;
2159 secdata = elf_section_data (stab);
2160 if (! _bfd_link_section_stabs (abfd,
2161 &elf_hash_table (info)->stab_info,
2162 stab, stabstr,
2163 &secdata->stab_info))
2164 goto error_return;
2169 return true;
2171 error_return:
2172 if (buf != NULL)
2173 free (buf);
2174 if (dynbuf != NULL)
2175 free (dynbuf);
2176 if (dynver != NULL)
2177 free (dynver);
2178 if (extversym != NULL)
2179 free (extversym);
2180 return false;
2183 /* Create some sections which will be filled in with dynamic linking
2184 information. ABFD is an input file which requires dynamic sections
2185 to be created. The dynamic sections take up virtual memory space
2186 when the final executable is run, so we need to create them before
2187 addresses are assigned to the output sections. We work out the
2188 actual contents and size of these sections later. */
2190 boolean
2191 elf_link_create_dynamic_sections (abfd, info)
2192 bfd *abfd;
2193 struct bfd_link_info *info;
2195 flagword flags;
2196 register asection *s;
2197 struct elf_link_hash_entry *h;
2198 struct elf_backend_data *bed;
2200 if (elf_hash_table (info)->dynamic_sections_created)
2201 return true;
2203 /* Make sure that all dynamic sections use the same input BFD. */
2204 if (elf_hash_table (info)->dynobj == NULL)
2205 elf_hash_table (info)->dynobj = abfd;
2206 else
2207 abfd = elf_hash_table (info)->dynobj;
2209 /* Note that we set the SEC_IN_MEMORY flag for all of these
2210 sections. */
2211 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2212 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2214 /* A dynamically linked executable has a .interp section, but a
2215 shared library does not. */
2216 if (! info->shared)
2218 s = bfd_make_section (abfd, ".interp");
2219 if (s == NULL
2220 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2221 return false;
2224 /* Create sections to hold version informations. These are removed
2225 if they are not needed. */
2226 s = bfd_make_section (abfd, ".gnu.version_d");
2227 if (s == NULL
2228 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2229 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2230 return false;
2232 s = bfd_make_section (abfd, ".gnu.version");
2233 if (s == NULL
2234 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2235 || ! bfd_set_section_alignment (abfd, s, 1))
2236 return false;
2238 s = bfd_make_section (abfd, ".gnu.version_r");
2239 if (s == NULL
2240 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2241 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2242 return false;
2244 s = bfd_make_section (abfd, ".dynsym");
2245 if (s == NULL
2246 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2247 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2248 return false;
2250 s = bfd_make_section (abfd, ".dynstr");
2251 if (s == NULL
2252 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2253 return false;
2255 /* Create a strtab to hold the dynamic symbol names. */
2256 if (elf_hash_table (info)->dynstr == NULL)
2258 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2259 if (elf_hash_table (info)->dynstr == NULL)
2260 return false;
2263 s = bfd_make_section (abfd, ".dynamic");
2264 if (s == NULL
2265 || ! bfd_set_section_flags (abfd, s, flags)
2266 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2267 return false;
2269 /* The special symbol _DYNAMIC is always set to the start of the
2270 .dynamic section. This call occurs before we have processed the
2271 symbols for any dynamic object, so we don't have to worry about
2272 overriding a dynamic definition. We could set _DYNAMIC in a
2273 linker script, but we only want to define it if we are, in fact,
2274 creating a .dynamic section. We don't want to define it if there
2275 is no .dynamic section, since on some ELF platforms the start up
2276 code examines it to decide how to initialize the process. */
2277 h = NULL;
2278 if (! (_bfd_generic_link_add_one_symbol
2279 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2280 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2281 (struct bfd_link_hash_entry **) &h)))
2282 return false;
2283 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2284 h->type = STT_OBJECT;
2286 if (info->shared
2287 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2288 return false;
2290 bed = get_elf_backend_data (abfd);
2292 s = bfd_make_section (abfd, ".hash");
2293 if (s == NULL
2294 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2295 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2296 return false;
2297 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2299 /* Let the backend create the rest of the sections. This lets the
2300 backend set the right flags. The backend will normally create
2301 the .got and .plt sections. */
2302 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2303 return false;
2305 elf_hash_table (info)->dynamic_sections_created = true;
2307 return true;
2310 /* Add an entry to the .dynamic table. */
2312 boolean
2313 elf_add_dynamic_entry (info, tag, val)
2314 struct bfd_link_info *info;
2315 bfd_vma tag;
2316 bfd_vma val;
2318 Elf_Internal_Dyn dyn;
2319 bfd *dynobj;
2320 asection *s;
2321 size_t newsize;
2322 bfd_byte *newcontents;
2324 dynobj = elf_hash_table (info)->dynobj;
2326 s = bfd_get_section_by_name (dynobj, ".dynamic");
2327 BFD_ASSERT (s != NULL);
2329 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2330 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2331 if (newcontents == NULL)
2332 return false;
2334 dyn.d_tag = tag;
2335 dyn.d_un.d_val = val;
2336 elf_swap_dyn_out (dynobj, &dyn,
2337 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2339 s->_raw_size = newsize;
2340 s->contents = newcontents;
2342 return true;
2345 /* Record a new local dynamic symbol. */
2347 boolean
2348 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2349 struct bfd_link_info *info;
2350 bfd *input_bfd;
2351 long input_indx;
2353 struct elf_link_local_dynamic_entry *entry;
2354 struct elf_link_hash_table *eht;
2355 struct bfd_strtab_hash *dynstr;
2356 Elf_External_Sym esym;
2357 unsigned long dynstr_index;
2358 char *name;
2360 /* See if the entry exists already. */
2361 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2362 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2363 return true;
2365 entry = (struct elf_link_local_dynamic_entry *)
2366 bfd_alloc (input_bfd, sizeof (*entry));
2367 if (entry == NULL)
2368 return false;
2370 /* Go find the symbol, so that we can find it's name. */
2371 if (bfd_seek (input_bfd,
2372 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2373 + input_indx * sizeof (Elf_External_Sym)),
2374 SEEK_SET) != 0
2375 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2376 != sizeof (Elf_External_Sym)))
2377 return false;
2378 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2380 name = (bfd_elf_string_from_elf_section
2381 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2382 entry->isym.st_name));
2384 dynstr = elf_hash_table (info)->dynstr;
2385 if (dynstr == NULL)
2387 /* Create a strtab to hold the dynamic symbol names. */
2388 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2389 if (dynstr == NULL)
2390 return false;
2393 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2394 if (dynstr_index == (unsigned long) -1)
2395 return false;
2396 entry->isym.st_name = dynstr_index;
2398 eht = elf_hash_table (info);
2400 entry->next = eht->dynlocal;
2401 eht->dynlocal = entry;
2402 entry->input_bfd = input_bfd;
2403 entry->input_indx = input_indx;
2404 eht->dynsymcount++;
2406 /* Whatever binding the symbol had before, it's now local. */
2407 entry->isym.st_info
2408 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2410 /* The dynindx will be set at the end of size_dynamic_sections. */
2412 return true;
2415 /* Read and swap the relocs from the section indicated by SHDR. This
2416 may be either a REL or a RELA section. The relocations are
2417 translated into RELA relocations and stored in INTERNAL_RELOCS,
2418 which should have already been allocated to contain enough space.
2419 The EXTERNAL_RELOCS are a buffer where the external form of the
2420 relocations should be stored.
2422 Returns false if something goes wrong. */
2424 static boolean
2425 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2426 internal_relocs)
2427 bfd *abfd;
2428 Elf_Internal_Shdr *shdr;
2429 PTR external_relocs;
2430 Elf_Internal_Rela *internal_relocs;
2432 struct elf_backend_data *bed;
2434 /* If there aren't any relocations, that's OK. */
2435 if (!shdr)
2436 return true;
2438 /* Position ourselves at the start of the section. */
2439 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2440 return false;
2442 /* Read the relocations. */
2443 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2444 != shdr->sh_size)
2445 return false;
2447 bed = get_elf_backend_data (abfd);
2449 /* Convert the external relocations to the internal format. */
2450 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2452 Elf_External_Rel *erel;
2453 Elf_External_Rel *erelend;
2454 Elf_Internal_Rela *irela;
2455 Elf_Internal_Rel *irel;
2457 erel = (Elf_External_Rel *) external_relocs;
2458 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2459 irela = internal_relocs;
2460 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2461 * sizeof (Elf_Internal_Rel)));
2462 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2464 unsigned char i;
2466 if (bed->s->swap_reloc_in)
2467 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2468 else
2469 elf_swap_reloc_in (abfd, erel, irel);
2471 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2473 irela[i].r_offset = irel[i].r_offset;
2474 irela[i].r_info = irel[i].r_info;
2475 irela[i].r_addend = 0;
2479 else
2481 Elf_External_Rela *erela;
2482 Elf_External_Rela *erelaend;
2483 Elf_Internal_Rela *irela;
2485 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2487 erela = (Elf_External_Rela *) external_relocs;
2488 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2489 irela = internal_relocs;
2490 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2492 if (bed->s->swap_reloca_in)
2493 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2494 else
2495 elf_swap_reloca_in (abfd, erela, irela);
2499 return true;
2502 /* Read and swap the relocs for a section O. They may have been
2503 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2504 not NULL, they are used as buffers to read into. They are known to
2505 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2506 the return value is allocated using either malloc or bfd_alloc,
2507 according to the KEEP_MEMORY argument. If O has two relocation
2508 sections (both REL and RELA relocations), then the REL_HDR
2509 relocations will appear first in INTERNAL_RELOCS, followed by the
2510 REL_HDR2 relocations. */
2512 Elf_Internal_Rela *
2513 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2514 keep_memory)
2515 bfd *abfd;
2516 asection *o;
2517 PTR external_relocs;
2518 Elf_Internal_Rela *internal_relocs;
2519 boolean keep_memory;
2521 Elf_Internal_Shdr *rel_hdr;
2522 PTR alloc1 = NULL;
2523 Elf_Internal_Rela *alloc2 = NULL;
2524 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2526 if (elf_section_data (o)->relocs != NULL)
2527 return elf_section_data (o)->relocs;
2529 if (o->reloc_count == 0)
2530 return NULL;
2532 rel_hdr = &elf_section_data (o)->rel_hdr;
2534 if (internal_relocs == NULL)
2536 size_t size;
2538 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2539 * sizeof (Elf_Internal_Rela));
2540 if (keep_memory)
2541 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2542 else
2543 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2544 if (internal_relocs == NULL)
2545 goto error_return;
2548 if (external_relocs == NULL)
2550 size_t size = (size_t) rel_hdr->sh_size;
2552 if (elf_section_data (o)->rel_hdr2)
2553 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2554 alloc1 = (PTR) bfd_malloc (size);
2555 if (alloc1 == NULL)
2556 goto error_return;
2557 external_relocs = alloc1;
2560 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2561 external_relocs,
2562 internal_relocs))
2563 goto error_return;
2564 if (!elf_link_read_relocs_from_section
2565 (abfd,
2566 elf_section_data (o)->rel_hdr2,
2567 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2568 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2569 * bed->s->int_rels_per_ext_rel)))
2570 goto error_return;
2572 /* Cache the results for next time, if we can. */
2573 if (keep_memory)
2574 elf_section_data (o)->relocs = internal_relocs;
2576 if (alloc1 != NULL)
2577 free (alloc1);
2579 /* Don't free alloc2, since if it was allocated we are passing it
2580 back (under the name of internal_relocs). */
2582 return internal_relocs;
2584 error_return:
2585 if (alloc1 != NULL)
2586 free (alloc1);
2587 if (alloc2 != NULL)
2588 free (alloc2);
2589 return NULL;
2592 /* Record an assignment to a symbol made by a linker script. We need
2593 this in case some dynamic object refers to this symbol. */
2595 /*ARGSUSED*/
2596 boolean
2597 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2598 bfd *output_bfd ATTRIBUTE_UNUSED;
2599 struct bfd_link_info *info;
2600 const char *name;
2601 boolean provide;
2603 struct elf_link_hash_entry *h;
2605 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2606 return true;
2608 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2609 if (h == NULL)
2610 return false;
2612 if (h->root.type == bfd_link_hash_new)
2613 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2615 /* If this symbol is being provided by the linker script, and it is
2616 currently defined by a dynamic object, but not by a regular
2617 object, then mark it as undefined so that the generic linker will
2618 force the correct value. */
2619 if (provide
2620 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2621 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2622 h->root.type = bfd_link_hash_undefined;
2624 /* If this symbol is not being provided by the linker script, and it is
2625 currently defined by a dynamic object, but not by a regular object,
2626 then clear out any version information because the symbol will not be
2627 associated with the dynamic object any more. */
2628 if (!provide
2629 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2630 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2631 h->verinfo.verdef = NULL;
2633 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2635 /* When possible, keep the original type of the symbol */
2636 if (h->type == STT_NOTYPE)
2637 h->type = STT_OBJECT;
2639 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2640 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2641 || info->shared)
2642 && h->dynindx == -1)
2644 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2645 return false;
2647 /* If this is a weak defined symbol, and we know a corresponding
2648 real symbol from the same dynamic object, make sure the real
2649 symbol is also made into a dynamic symbol. */
2650 if (h->weakdef != NULL
2651 && h->weakdef->dynindx == -1)
2653 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2654 return false;
2658 return true;
2661 /* This structure is used to pass information to
2662 elf_link_assign_sym_version. */
2664 struct elf_assign_sym_version_info
2666 /* Output BFD. */
2667 bfd *output_bfd;
2668 /* General link information. */
2669 struct bfd_link_info *info;
2670 /* Version tree. */
2671 struct bfd_elf_version_tree *verdefs;
2672 /* Whether we are exporting all dynamic symbols. */
2673 boolean export_dynamic;
2674 /* Whether we had a failure. */
2675 boolean failed;
2678 /* This structure is used to pass information to
2679 elf_link_find_version_dependencies. */
2681 struct elf_find_verdep_info
2683 /* Output BFD. */
2684 bfd *output_bfd;
2685 /* General link information. */
2686 struct bfd_link_info *info;
2687 /* The number of dependencies. */
2688 unsigned int vers;
2689 /* Whether we had a failure. */
2690 boolean failed;
2693 /* Array used to determine the number of hash table buckets to use
2694 based on the number of symbols there are. If there are fewer than
2695 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2696 fewer than 37 we use 17 buckets, and so forth. We never use more
2697 than 32771 buckets. */
2699 static const size_t elf_buckets[] =
2701 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2702 16411, 32771, 0
2705 /* Compute bucket count for hashing table. We do not use a static set
2706 of possible tables sizes anymore. Instead we determine for all
2707 possible reasonable sizes of the table the outcome (i.e., the
2708 number of collisions etc) and choose the best solution. The
2709 weighting functions are not too simple to allow the table to grow
2710 without bounds. Instead one of the weighting factors is the size.
2711 Therefore the result is always a good payoff between few collisions
2712 (= short chain lengths) and table size. */
2713 static size_t
2714 compute_bucket_count (info)
2715 struct bfd_link_info *info;
2717 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2718 size_t best_size = 0;
2719 unsigned long int *hashcodes;
2720 unsigned long int *hashcodesp;
2721 unsigned long int i;
2723 /* Compute the hash values for all exported symbols. At the same
2724 time store the values in an array so that we could use them for
2725 optimizations. */
2726 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2727 * sizeof (unsigned long int));
2728 if (hashcodes == NULL)
2729 return 0;
2730 hashcodesp = hashcodes;
2732 /* Put all hash values in HASHCODES. */
2733 elf_link_hash_traverse (elf_hash_table (info),
2734 elf_collect_hash_codes, &hashcodesp);
2736 /* We have a problem here. The following code to optimize the table
2737 size requires an integer type with more the 32 bits. If
2738 BFD_HOST_U_64_BIT is set we know about such a type. */
2739 #ifdef BFD_HOST_U_64_BIT
2740 if (info->optimize == true)
2742 unsigned long int nsyms = hashcodesp - hashcodes;
2743 size_t minsize;
2744 size_t maxsize;
2745 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2746 unsigned long int *counts ;
2748 /* Possible optimization parameters: if we have NSYMS symbols we say
2749 that the hashing table must at least have NSYMS/4 and at most
2750 2*NSYMS buckets. */
2751 minsize = nsyms / 4;
2752 if (minsize == 0)
2753 minsize = 1;
2754 best_size = maxsize = nsyms * 2;
2756 /* Create array where we count the collisions in. We must use bfd_malloc
2757 since the size could be large. */
2758 counts = (unsigned long int *) bfd_malloc (maxsize
2759 * sizeof (unsigned long int));
2760 if (counts == NULL)
2762 free (hashcodes);
2763 return 0;
2766 /* Compute the "optimal" size for the hash table. The criteria is a
2767 minimal chain length. The minor criteria is (of course) the size
2768 of the table. */
2769 for (i = minsize; i < maxsize; ++i)
2771 /* Walk through the array of hashcodes and count the collisions. */
2772 BFD_HOST_U_64_BIT max;
2773 unsigned long int j;
2774 unsigned long int fact;
2776 memset (counts, '\0', i * sizeof (unsigned long int));
2778 /* Determine how often each hash bucket is used. */
2779 for (j = 0; j < nsyms; ++j)
2780 ++counts[hashcodes[j] % i];
2782 /* For the weight function we need some information about the
2783 pagesize on the target. This is information need not be 100%
2784 accurate. Since this information is not available (so far) we
2785 define it here to a reasonable default value. If it is crucial
2786 to have a better value some day simply define this value. */
2787 # ifndef BFD_TARGET_PAGESIZE
2788 # define BFD_TARGET_PAGESIZE (4096)
2789 # endif
2791 /* We in any case need 2 + NSYMS entries for the size values and
2792 the chains. */
2793 max = (2 + nsyms) * (ARCH_SIZE / 8);
2795 # if 1
2796 /* Variant 1: optimize for short chains. We add the squares
2797 of all the chain lengths (which favous many small chain
2798 over a few long chains). */
2799 for (j = 0; j < i; ++j)
2800 max += counts[j] * counts[j];
2802 /* This adds penalties for the overall size of the table. */
2803 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2804 max *= fact * fact;
2805 # else
2806 /* Variant 2: Optimize a lot more for small table. Here we
2807 also add squares of the size but we also add penalties for
2808 empty slots (the +1 term). */
2809 for (j = 0; j < i; ++j)
2810 max += (1 + counts[j]) * (1 + counts[j]);
2812 /* The overall size of the table is considered, but not as
2813 strong as in variant 1, where it is squared. */
2814 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2815 max *= fact;
2816 # endif
2818 /* Compare with current best results. */
2819 if (max < best_chlen)
2821 best_chlen = max;
2822 best_size = i;
2826 free (counts);
2828 else
2829 #endif /* defined (BFD_HOST_U_64_BIT) */
2831 /* This is the fallback solution if no 64bit type is available or if we
2832 are not supposed to spend much time on optimizations. We select the
2833 bucket count using a fixed set of numbers. */
2834 for (i = 0; elf_buckets[i] != 0; i++)
2836 best_size = elf_buckets[i];
2837 if (dynsymcount < elf_buckets[i + 1])
2838 break;
2842 /* Free the arrays we needed. */
2843 free (hashcodes);
2845 return best_size;
2848 /* Set up the sizes and contents of the ELF dynamic sections. This is
2849 called by the ELF linker emulation before_allocation routine. We
2850 must set the sizes of the sections before the linker sets the
2851 addresses of the various sections. */
2853 boolean
2854 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2855 export_dynamic, filter_shlib,
2856 auxiliary_filters, info, sinterpptr,
2857 verdefs)
2858 bfd *output_bfd;
2859 const char *soname;
2860 const char *rpath;
2861 boolean export_dynamic;
2862 const char *filter_shlib;
2863 const char * const *auxiliary_filters;
2864 struct bfd_link_info *info;
2865 asection **sinterpptr;
2866 struct bfd_elf_version_tree *verdefs;
2868 bfd_size_type soname_indx;
2869 bfd *dynobj;
2870 struct elf_backend_data *bed;
2871 struct elf_assign_sym_version_info asvinfo;
2873 *sinterpptr = NULL;
2875 soname_indx = (bfd_size_type) -1;
2877 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2878 return true;
2880 /* The backend may have to create some sections regardless of whether
2881 we're dynamic or not. */
2882 bed = get_elf_backend_data (output_bfd);
2883 if (bed->elf_backend_always_size_sections
2884 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2885 return false;
2887 dynobj = elf_hash_table (info)->dynobj;
2889 /* If there were no dynamic objects in the link, there is nothing to
2890 do here. */
2891 if (dynobj == NULL)
2892 return true;
2894 if (elf_hash_table (info)->dynamic_sections_created)
2896 struct elf_info_failed eif;
2897 struct elf_link_hash_entry *h;
2898 asection *dynstr;
2900 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2901 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2903 if (soname != NULL)
2905 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2906 soname, true, true);
2907 if (soname_indx == (bfd_size_type) -1
2908 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2909 return false;
2912 if (info->symbolic)
2914 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2915 return false;
2916 info->flags |= DF_SYMBOLIC;
2919 if (rpath != NULL)
2921 bfd_size_type indx;
2923 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2924 true, true);
2925 if (indx == (bfd_size_type) -1
2926 || ! elf_add_dynamic_entry (info, DT_RPATH, indx)
2927 || (info->new_dtags
2928 && ! elf_add_dynamic_entry (info, DT_RUNPATH, indx)))
2929 return false;
2932 if (filter_shlib != NULL)
2934 bfd_size_type indx;
2936 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2937 filter_shlib, true, true);
2938 if (indx == (bfd_size_type) -1
2939 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2940 return false;
2943 if (auxiliary_filters != NULL)
2945 const char * const *p;
2947 for (p = auxiliary_filters; *p != NULL; p++)
2949 bfd_size_type indx;
2951 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2952 *p, true, true);
2953 if (indx == (bfd_size_type) -1
2954 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2955 return false;
2959 /* If we are supposed to export all symbols into the dynamic symbol
2960 table (this is not the normal case), then do so. */
2961 if (export_dynamic)
2963 struct elf_info_failed eif;
2965 eif.failed = false;
2966 eif.info = info;
2967 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2968 (PTR) &eif);
2969 if (eif.failed)
2970 return false;
2973 /* Attach all the symbols to their version information. */
2974 asvinfo.output_bfd = output_bfd;
2975 asvinfo.info = info;
2976 asvinfo.verdefs = verdefs;
2977 asvinfo.export_dynamic = export_dynamic;
2978 asvinfo.failed = false;
2980 elf_link_hash_traverse (elf_hash_table (info),
2981 elf_link_assign_sym_version,
2982 (PTR) &asvinfo);
2983 if (asvinfo.failed)
2984 return false;
2986 /* Find all symbols which were defined in a dynamic object and make
2987 the backend pick a reasonable value for them. */
2988 eif.failed = false;
2989 eif.info = info;
2990 elf_link_hash_traverse (elf_hash_table (info),
2991 elf_adjust_dynamic_symbol,
2992 (PTR) &eif);
2993 if (eif.failed)
2994 return false;
2996 /* Add some entries to the .dynamic section. We fill in some of the
2997 values later, in elf_bfd_final_link, but we must add the entries
2998 now so that we know the final size of the .dynamic section. */
3000 /* If there are initialization and/or finalization functions to
3001 call then add the corresponding DT_INIT/DT_FINI entries. */
3002 h = (info->init_function
3003 ? elf_link_hash_lookup (elf_hash_table (info),
3004 info->init_function, false,
3005 false, false)
3006 : NULL);
3007 if (h != NULL
3008 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3009 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3011 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
3012 return false;
3014 h = (info->fini_function
3015 ? elf_link_hash_lookup (elf_hash_table (info),
3016 info->fini_function, false,
3017 false, false)
3018 : NULL);
3019 if (h != NULL
3020 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3021 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3023 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
3024 return false;
3027 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
3028 /* If .dynstr is excluded from the link, we don't want any of
3029 these tags. Strictly, we should be checking each section
3030 individually; This quick check covers for the case where
3031 someone does a /DISCARD/ : { *(*) }. */
3032 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
3034 bfd_size_type strsize;
3036 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3037 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
3038 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
3039 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
3040 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
3041 || ! elf_add_dynamic_entry (info, DT_SYMENT,
3042 sizeof (Elf_External_Sym)))
3043 return false;
3047 /* The backend must work out the sizes of all the other dynamic
3048 sections. */
3049 if (bed->elf_backend_size_dynamic_sections
3050 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
3051 return false;
3053 if (elf_hash_table (info)->dynamic_sections_created)
3055 size_t dynsymcount;
3056 asection *s;
3057 size_t bucketcount = 0;
3058 size_t hash_entry_size;
3060 /* Set up the version definition section. */
3061 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3062 BFD_ASSERT (s != NULL);
3064 /* We may have created additional version definitions if we are
3065 just linking a regular application. */
3066 verdefs = asvinfo.verdefs;
3068 if (verdefs == NULL)
3069 _bfd_strip_section_from_output (info, s);
3070 else
3072 unsigned int cdefs;
3073 bfd_size_type size;
3074 struct bfd_elf_version_tree *t;
3075 bfd_byte *p;
3076 Elf_Internal_Verdef def;
3077 Elf_Internal_Verdaux defaux;
3079 cdefs = 0;
3080 size = 0;
3082 /* Make space for the base version. */
3083 size += sizeof (Elf_External_Verdef);
3084 size += sizeof (Elf_External_Verdaux);
3085 ++cdefs;
3087 for (t = verdefs; t != NULL; t = t->next)
3089 struct bfd_elf_version_deps *n;
3091 size += sizeof (Elf_External_Verdef);
3092 size += sizeof (Elf_External_Verdaux);
3093 ++cdefs;
3095 for (n = t->deps; n != NULL; n = n->next)
3096 size += sizeof (Elf_External_Verdaux);
3099 s->_raw_size = size;
3100 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3101 if (s->contents == NULL && s->_raw_size != 0)
3102 return false;
3104 /* Fill in the version definition section. */
3106 p = s->contents;
3108 def.vd_version = VER_DEF_CURRENT;
3109 def.vd_flags = VER_FLG_BASE;
3110 def.vd_ndx = 1;
3111 def.vd_cnt = 1;
3112 def.vd_aux = sizeof (Elf_External_Verdef);
3113 def.vd_next = (sizeof (Elf_External_Verdef)
3114 + sizeof (Elf_External_Verdaux));
3116 if (soname_indx != (bfd_size_type) -1)
3118 def.vd_hash = bfd_elf_hash (soname);
3119 defaux.vda_name = soname_indx;
3121 else
3123 const char *name;
3124 bfd_size_type indx;
3126 name = output_bfd->filename;
3127 def.vd_hash = bfd_elf_hash (name);
3128 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3129 name, true, false);
3130 if (indx == (bfd_size_type) -1)
3131 return false;
3132 defaux.vda_name = indx;
3134 defaux.vda_next = 0;
3136 _bfd_elf_swap_verdef_out (output_bfd, &def,
3137 (Elf_External_Verdef *)p);
3138 p += sizeof (Elf_External_Verdef);
3139 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3140 (Elf_External_Verdaux *) p);
3141 p += sizeof (Elf_External_Verdaux);
3143 for (t = verdefs; t != NULL; t = t->next)
3145 unsigned int cdeps;
3146 struct bfd_elf_version_deps *n;
3147 struct elf_link_hash_entry *h;
3149 cdeps = 0;
3150 for (n = t->deps; n != NULL; n = n->next)
3151 ++cdeps;
3153 /* Add a symbol representing this version. */
3154 h = NULL;
3155 if (! (_bfd_generic_link_add_one_symbol
3156 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3157 (bfd_vma) 0, (const char *) NULL, false,
3158 get_elf_backend_data (dynobj)->collect,
3159 (struct bfd_link_hash_entry **) &h)))
3160 return false;
3161 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3162 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3163 h->type = STT_OBJECT;
3164 h->verinfo.vertree = t;
3166 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3167 return false;
3169 def.vd_version = VER_DEF_CURRENT;
3170 def.vd_flags = 0;
3171 if (t->globals == NULL && t->locals == NULL && ! t->used)
3172 def.vd_flags |= VER_FLG_WEAK;
3173 def.vd_ndx = t->vernum + 1;
3174 def.vd_cnt = cdeps + 1;
3175 def.vd_hash = bfd_elf_hash (t->name);
3176 def.vd_aux = sizeof (Elf_External_Verdef);
3177 if (t->next != NULL)
3178 def.vd_next = (sizeof (Elf_External_Verdef)
3179 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3180 else
3181 def.vd_next = 0;
3183 _bfd_elf_swap_verdef_out (output_bfd, &def,
3184 (Elf_External_Verdef *) p);
3185 p += sizeof (Elf_External_Verdef);
3187 defaux.vda_name = h->dynstr_index;
3188 if (t->deps == NULL)
3189 defaux.vda_next = 0;
3190 else
3191 defaux.vda_next = sizeof (Elf_External_Verdaux);
3192 t->name_indx = defaux.vda_name;
3194 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3195 (Elf_External_Verdaux *) p);
3196 p += sizeof (Elf_External_Verdaux);
3198 for (n = t->deps; n != NULL; n = n->next)
3200 if (n->version_needed == NULL)
3202 /* This can happen if there was an error in the
3203 version script. */
3204 defaux.vda_name = 0;
3206 else
3207 defaux.vda_name = n->version_needed->name_indx;
3208 if (n->next == NULL)
3209 defaux.vda_next = 0;
3210 else
3211 defaux.vda_next = sizeof (Elf_External_Verdaux);
3213 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3214 (Elf_External_Verdaux *) p);
3215 p += sizeof (Elf_External_Verdaux);
3219 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3220 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3221 return false;
3223 elf_tdata (output_bfd)->cverdefs = cdefs;
3226 if (info->new_dtags && info->flags)
3228 if (! elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
3229 return false;
3232 if (info->flags_1)
3234 if (! info->shared)
3235 info->flags_1 &= ~ (DF_1_INITFIRST
3236 | DF_1_NODELETE
3237 | DF_1_NOOPEN);
3238 if (! elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
3239 return false;
3242 /* Work out the size of the version reference section. */
3244 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3245 BFD_ASSERT (s != NULL);
3247 struct elf_find_verdep_info sinfo;
3249 sinfo.output_bfd = output_bfd;
3250 sinfo.info = info;
3251 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3252 if (sinfo.vers == 0)
3253 sinfo.vers = 1;
3254 sinfo.failed = false;
3256 elf_link_hash_traverse (elf_hash_table (info),
3257 elf_link_find_version_dependencies,
3258 (PTR) &sinfo);
3260 if (elf_tdata (output_bfd)->verref == NULL)
3261 _bfd_strip_section_from_output (info, s);
3262 else
3264 Elf_Internal_Verneed *t;
3265 unsigned int size;
3266 unsigned int crefs;
3267 bfd_byte *p;
3269 /* Build the version definition section. */
3270 size = 0;
3271 crefs = 0;
3272 for (t = elf_tdata (output_bfd)->verref;
3273 t != NULL;
3274 t = t->vn_nextref)
3276 Elf_Internal_Vernaux *a;
3278 size += sizeof (Elf_External_Verneed);
3279 ++crefs;
3280 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3281 size += sizeof (Elf_External_Vernaux);
3284 s->_raw_size = size;
3285 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3286 if (s->contents == NULL)
3287 return false;
3289 p = s->contents;
3290 for (t = elf_tdata (output_bfd)->verref;
3291 t != NULL;
3292 t = t->vn_nextref)
3294 unsigned int caux;
3295 Elf_Internal_Vernaux *a;
3296 bfd_size_type indx;
3298 caux = 0;
3299 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3300 ++caux;
3302 t->vn_version = VER_NEED_CURRENT;
3303 t->vn_cnt = caux;
3304 if (elf_dt_name (t->vn_bfd) != NULL)
3305 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3306 elf_dt_name (t->vn_bfd),
3307 true, false);
3308 else
3309 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3310 t->vn_bfd->filename, true, false);
3311 if (indx == (bfd_size_type) -1)
3312 return false;
3313 t->vn_file = indx;
3314 t->vn_aux = sizeof (Elf_External_Verneed);
3315 if (t->vn_nextref == NULL)
3316 t->vn_next = 0;
3317 else
3318 t->vn_next = (sizeof (Elf_External_Verneed)
3319 + caux * sizeof (Elf_External_Vernaux));
3321 _bfd_elf_swap_verneed_out (output_bfd, t,
3322 (Elf_External_Verneed *) p);
3323 p += sizeof (Elf_External_Verneed);
3325 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3327 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3328 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3329 a->vna_nodename, true, false);
3330 if (indx == (bfd_size_type) -1)
3331 return false;
3332 a->vna_name = indx;
3333 if (a->vna_nextptr == NULL)
3334 a->vna_next = 0;
3335 else
3336 a->vna_next = sizeof (Elf_External_Vernaux);
3338 _bfd_elf_swap_vernaux_out (output_bfd, a,
3339 (Elf_External_Vernaux *) p);
3340 p += sizeof (Elf_External_Vernaux);
3344 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3345 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3346 return false;
3348 elf_tdata (output_bfd)->cverrefs = crefs;
3352 /* Assign dynsym indicies. In a shared library we generate a
3353 section symbol for each output section, which come first.
3354 Next come all of the back-end allocated local dynamic syms,
3355 followed by the rest of the global symbols. */
3357 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3359 /* Work out the size of the symbol version section. */
3360 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3361 BFD_ASSERT (s != NULL);
3362 if (dynsymcount == 0
3363 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3365 _bfd_strip_section_from_output (info, s);
3366 /* The DYNSYMCOUNT might have changed if we were going to
3367 output a dynamic symbol table entry for S. */
3368 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3370 else
3372 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3373 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3374 if (s->contents == NULL)
3375 return false;
3377 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3378 return false;
3381 /* Set the size of the .dynsym and .hash sections. We counted
3382 the number of dynamic symbols in elf_link_add_object_symbols.
3383 We will build the contents of .dynsym and .hash when we build
3384 the final symbol table, because until then we do not know the
3385 correct value to give the symbols. We built the .dynstr
3386 section as we went along in elf_link_add_object_symbols. */
3387 s = bfd_get_section_by_name (dynobj, ".dynsym");
3388 BFD_ASSERT (s != NULL);
3389 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3390 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3391 if (s->contents == NULL && s->_raw_size != 0)
3392 return false;
3394 if (dynsymcount != 0)
3396 Elf_Internal_Sym isym;
3398 /* The first entry in .dynsym is a dummy symbol. */
3399 isym.st_value = 0;
3400 isym.st_size = 0;
3401 isym.st_name = 0;
3402 isym.st_info = 0;
3403 isym.st_other = 0;
3404 isym.st_shndx = 0;
3405 elf_swap_symbol_out (output_bfd, &isym,
3406 (PTR) (Elf_External_Sym *) s->contents);
3409 /* Compute the size of the hashing table. As a side effect this
3410 computes the hash values for all the names we export. */
3411 bucketcount = compute_bucket_count (info);
3413 s = bfd_get_section_by_name (dynobj, ".hash");
3414 BFD_ASSERT (s != NULL);
3415 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3416 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3417 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3418 if (s->contents == NULL)
3419 return false;
3420 memset (s->contents, 0, (size_t) s->_raw_size);
3422 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3423 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3424 s->contents + hash_entry_size);
3426 elf_hash_table (info)->bucketcount = bucketcount;
3428 s = bfd_get_section_by_name (dynobj, ".dynstr");
3429 BFD_ASSERT (s != NULL);
3430 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3432 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3433 return false;
3436 return true;
3439 /* Fix up the flags for a symbol. This handles various cases which
3440 can only be fixed after all the input files are seen. This is
3441 currently called by both adjust_dynamic_symbol and
3442 assign_sym_version, which is unnecessary but perhaps more robust in
3443 the face of future changes. */
3445 static boolean
3446 elf_fix_symbol_flags (h, eif)
3447 struct elf_link_hash_entry *h;
3448 struct elf_info_failed *eif;
3450 /* If this symbol was mentioned in a non-ELF file, try to set
3451 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3452 permit a non-ELF file to correctly refer to a symbol defined in
3453 an ELF dynamic object. */
3454 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3456 while (h->root.type == bfd_link_hash_indirect)
3457 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3459 if (h->root.type != bfd_link_hash_defined
3460 && h->root.type != bfd_link_hash_defweak)
3461 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3462 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3463 else
3465 if (h->root.u.def.section->owner != NULL
3466 && (bfd_get_flavour (h->root.u.def.section->owner)
3467 == bfd_target_elf_flavour))
3468 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3469 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3470 else
3471 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3474 if (h->dynindx == -1
3475 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3476 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3478 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3480 eif->failed = true;
3481 return false;
3485 else
3487 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3488 was first seen in a non-ELF file. Fortunately, if the symbol
3489 was first seen in an ELF file, we're probably OK unless the
3490 symbol was defined in a non-ELF file. Catch that case here.
3491 FIXME: We're still in trouble if the symbol was first seen in
3492 a dynamic object, and then later in a non-ELF regular object. */
3493 if ((h->root.type == bfd_link_hash_defined
3494 || h->root.type == bfd_link_hash_defweak)
3495 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3496 && (h->root.u.def.section->owner != NULL
3497 ? (bfd_get_flavour (h->root.u.def.section->owner)
3498 != bfd_target_elf_flavour)
3499 : (bfd_is_abs_section (h->root.u.def.section)
3500 && (h->elf_link_hash_flags
3501 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3502 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3505 /* If this is a final link, and the symbol was defined as a common
3506 symbol in a regular object file, and there was no definition in
3507 any dynamic object, then the linker will have allocated space for
3508 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3509 flag will not have been set. */
3510 if (h->root.type == bfd_link_hash_defined
3511 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3512 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3513 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3514 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3515 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3517 /* If -Bsymbolic was used (which means to bind references to global
3518 symbols to the definition within the shared object), and this
3519 symbol was defined in a regular object, then it actually doesn't
3520 need a PLT entry. Likewise, if the symbol has any kind of
3521 visibility (internal, hidden, or protected), it doesn't need a
3522 PLT. */
3523 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3524 && eif->info->shared
3525 && (eif->info->symbolic || ELF_ST_VISIBILITY (h->other))
3526 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3528 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3529 h->plt.offset = (bfd_vma) -1;
3532 /* If this is a weak defined symbol in a dynamic object, and we know
3533 the real definition in the dynamic object, copy interesting flags
3534 over to the real definition. */
3535 if (h->weakdef != NULL)
3537 struct elf_link_hash_entry *weakdef;
3539 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3540 || h->root.type == bfd_link_hash_defweak);
3541 weakdef = h->weakdef;
3542 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3543 || weakdef->root.type == bfd_link_hash_defweak);
3544 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3546 /* If the real definition is defined by a regular object file,
3547 don't do anything special. See the longer description in
3548 elf_adjust_dynamic_symbol, below. */
3549 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3550 h->weakdef = NULL;
3551 else
3552 weakdef->elf_link_hash_flags |=
3553 (h->elf_link_hash_flags
3554 & (ELF_LINK_HASH_REF_REGULAR
3555 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3556 | ELF_LINK_NON_GOT_REF));
3559 return true;
3562 /* Make the backend pick a good value for a dynamic symbol. This is
3563 called via elf_link_hash_traverse, and also calls itself
3564 recursively. */
3566 static boolean
3567 elf_adjust_dynamic_symbol (h, data)
3568 struct elf_link_hash_entry *h;
3569 PTR data;
3571 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3572 bfd *dynobj;
3573 struct elf_backend_data *bed;
3575 /* Ignore indirect symbols. These are added by the versioning code. */
3576 if (h->root.type == bfd_link_hash_indirect)
3577 return true;
3579 /* Fix the symbol flags. */
3580 if (! elf_fix_symbol_flags (h, eif))
3581 return false;
3583 /* If this symbol does not require a PLT entry, and it is not
3584 defined by a dynamic object, or is not referenced by a regular
3585 object, ignore it. We do have to handle a weak defined symbol,
3586 even if no regular object refers to it, if we decided to add it
3587 to the dynamic symbol table. FIXME: Do we normally need to worry
3588 about symbols which are defined by one dynamic object and
3589 referenced by another one? */
3590 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3591 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3592 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3593 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3594 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3596 h->plt.offset = (bfd_vma) -1;
3597 return true;
3600 /* If we've already adjusted this symbol, don't do it again. This
3601 can happen via a recursive call. */
3602 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3603 return true;
3605 /* Don't look at this symbol again. Note that we must set this
3606 after checking the above conditions, because we may look at a
3607 symbol once, decide not to do anything, and then get called
3608 recursively later after REF_REGULAR is set below. */
3609 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3611 /* If this is a weak definition, and we know a real definition, and
3612 the real symbol is not itself defined by a regular object file,
3613 then get a good value for the real definition. We handle the
3614 real symbol first, for the convenience of the backend routine.
3616 Note that there is a confusing case here. If the real definition
3617 is defined by a regular object file, we don't get the real symbol
3618 from the dynamic object, but we do get the weak symbol. If the
3619 processor backend uses a COPY reloc, then if some routine in the
3620 dynamic object changes the real symbol, we will not see that
3621 change in the corresponding weak symbol. This is the way other
3622 ELF linkers work as well, and seems to be a result of the shared
3623 library model.
3625 I will clarify this issue. Most SVR4 shared libraries define the
3626 variable _timezone and define timezone as a weak synonym. The
3627 tzset call changes _timezone. If you write
3628 extern int timezone;
3629 int _timezone = 5;
3630 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3631 you might expect that, since timezone is a synonym for _timezone,
3632 the same number will print both times. However, if the processor
3633 backend uses a COPY reloc, then actually timezone will be copied
3634 into your process image, and, since you define _timezone
3635 yourself, _timezone will not. Thus timezone and _timezone will
3636 wind up at different memory locations. The tzset call will set
3637 _timezone, leaving timezone unchanged. */
3639 if (h->weakdef != NULL)
3641 /* If we get to this point, we know there is an implicit
3642 reference by a regular object file via the weak symbol H.
3643 FIXME: Is this really true? What if the traversal finds
3644 H->WEAKDEF before it finds H? */
3645 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3647 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3648 return false;
3651 /* If a symbol has no type and no size and does not require a PLT
3652 entry, then we are probably about to do the wrong thing here: we
3653 are probably going to create a COPY reloc for an empty object.
3654 This case can arise when a shared object is built with assembly
3655 code, and the assembly code fails to set the symbol type. */
3656 if (h->size == 0
3657 && h->type == STT_NOTYPE
3658 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3659 (*_bfd_error_handler)
3660 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3661 h->root.root.string);
3663 dynobj = elf_hash_table (eif->info)->dynobj;
3664 bed = get_elf_backend_data (dynobj);
3665 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3667 eif->failed = true;
3668 return false;
3671 return true;
3674 /* This routine is used to export all defined symbols into the dynamic
3675 symbol table. It is called via elf_link_hash_traverse. */
3677 static boolean
3678 elf_export_symbol (h, data)
3679 struct elf_link_hash_entry *h;
3680 PTR data;
3682 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3684 /* Ignore indirect symbols. These are added by the versioning code. */
3685 if (h->root.type == bfd_link_hash_indirect)
3686 return true;
3688 if (h->dynindx == -1
3689 && (h->elf_link_hash_flags
3690 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3692 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3694 eif->failed = true;
3695 return false;
3699 return true;
3702 /* Look through the symbols which are defined in other shared
3703 libraries and referenced here. Update the list of version
3704 dependencies. This will be put into the .gnu.version_r section.
3705 This function is called via elf_link_hash_traverse. */
3707 static boolean
3708 elf_link_find_version_dependencies (h, data)
3709 struct elf_link_hash_entry *h;
3710 PTR data;
3712 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3713 Elf_Internal_Verneed *t;
3714 Elf_Internal_Vernaux *a;
3716 /* We only care about symbols defined in shared objects with version
3717 information. */
3718 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3719 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3720 || h->dynindx == -1
3721 || h->verinfo.verdef == NULL)
3722 return true;
3724 /* See if we already know about this version. */
3725 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3727 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3728 continue;
3730 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3731 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3732 return true;
3734 break;
3737 /* This is a new version. Add it to tree we are building. */
3739 if (t == NULL)
3741 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3742 if (t == NULL)
3744 rinfo->failed = true;
3745 return false;
3748 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3749 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3750 elf_tdata (rinfo->output_bfd)->verref = t;
3753 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3755 /* Note that we are copying a string pointer here, and testing it
3756 above. If bfd_elf_string_from_elf_section is ever changed to
3757 discard the string data when low in memory, this will have to be
3758 fixed. */
3759 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3761 a->vna_flags = h->verinfo.verdef->vd_flags;
3762 a->vna_nextptr = t->vn_auxptr;
3764 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3765 ++rinfo->vers;
3767 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3769 t->vn_auxptr = a;
3771 return true;
3774 /* Figure out appropriate versions for all the symbols. We may not
3775 have the version number script until we have read all of the input
3776 files, so until that point we don't know which symbols should be
3777 local. This function is called via elf_link_hash_traverse. */
3779 static boolean
3780 elf_link_assign_sym_version (h, data)
3781 struct elf_link_hash_entry *h;
3782 PTR data;
3784 struct elf_assign_sym_version_info *sinfo =
3785 (struct elf_assign_sym_version_info *) data;
3786 struct bfd_link_info *info = sinfo->info;
3787 struct elf_backend_data *bed;
3788 struct elf_info_failed eif;
3789 char *p;
3791 /* Fix the symbol flags. */
3792 eif.failed = false;
3793 eif.info = info;
3794 if (! elf_fix_symbol_flags (h, &eif))
3796 if (eif.failed)
3797 sinfo->failed = true;
3798 return false;
3801 /* We only need version numbers for symbols defined in regular
3802 objects. */
3803 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3804 return true;
3806 bed = get_elf_backend_data (sinfo->output_bfd);
3807 p = strchr (h->root.root.string, ELF_VER_CHR);
3808 if (p != NULL && h->verinfo.vertree == NULL)
3810 struct bfd_elf_version_tree *t;
3811 boolean hidden;
3813 hidden = true;
3815 /* There are two consecutive ELF_VER_CHR characters if this is
3816 not a hidden symbol. */
3817 ++p;
3818 if (*p == ELF_VER_CHR)
3820 hidden = false;
3821 ++p;
3824 /* If there is no version string, we can just return out. */
3825 if (*p == '\0')
3827 if (hidden)
3828 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3829 return true;
3832 /* Look for the version. If we find it, it is no longer weak. */
3833 for (t = sinfo->verdefs; t != NULL; t = t->next)
3835 if (strcmp (t->name, p) == 0)
3837 int len;
3838 char *alc;
3839 struct bfd_elf_version_expr *d;
3841 len = p - h->root.root.string;
3842 alc = bfd_alloc (sinfo->output_bfd, len);
3843 if (alc == NULL)
3844 return false;
3845 strncpy (alc, h->root.root.string, len - 1);
3846 alc[len - 1] = '\0';
3847 if (alc[len - 2] == ELF_VER_CHR)
3848 alc[len - 2] = '\0';
3850 h->verinfo.vertree = t;
3851 t->used = true;
3852 d = NULL;
3854 if (t->globals != NULL)
3856 for (d = t->globals; d != NULL; d = d->next)
3857 if ((*d->match) (d, alc))
3858 break;
3861 /* See if there is anything to force this symbol to
3862 local scope. */
3863 if (d == NULL && t->locals != NULL)
3865 for (d = t->locals; d != NULL; d = d->next)
3867 if ((*d->match) (d, alc))
3869 if (h->dynindx != -1
3870 && info->shared
3871 && ! sinfo->export_dynamic)
3873 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3874 (*bed->elf_backend_hide_symbol) (info, h);
3875 /* FIXME: The name of the symbol has
3876 already been recorded in the dynamic
3877 string table section. */
3880 break;
3885 bfd_release (sinfo->output_bfd, alc);
3886 break;
3890 /* If we are building an application, we need to create a
3891 version node for this version. */
3892 if (t == NULL && ! info->shared)
3894 struct bfd_elf_version_tree **pp;
3895 int version_index;
3897 /* If we aren't going to export this symbol, we don't need
3898 to worry about it. */
3899 if (h->dynindx == -1)
3900 return true;
3902 t = ((struct bfd_elf_version_tree *)
3903 bfd_alloc (sinfo->output_bfd, sizeof *t));
3904 if (t == NULL)
3906 sinfo->failed = true;
3907 return false;
3910 t->next = NULL;
3911 t->name = p;
3912 t->globals = NULL;
3913 t->locals = NULL;
3914 t->deps = NULL;
3915 t->name_indx = (unsigned int) -1;
3916 t->used = true;
3918 version_index = 1;
3919 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3920 ++version_index;
3921 t->vernum = version_index;
3923 *pp = t;
3925 h->verinfo.vertree = t;
3927 else if (t == NULL)
3929 /* We could not find the version for a symbol when
3930 generating a shared archive. Return an error. */
3931 (*_bfd_error_handler)
3932 (_("%s: undefined versioned symbol name %s"),
3933 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3934 bfd_set_error (bfd_error_bad_value);
3935 sinfo->failed = true;
3936 return false;
3939 if (hidden)
3940 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3943 /* If we don't have a version for this symbol, see if we can find
3944 something. */
3945 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3947 struct bfd_elf_version_tree *t;
3948 struct bfd_elf_version_tree *deflt;
3949 struct bfd_elf_version_expr *d;
3951 /* See if can find what version this symbol is in. If the
3952 symbol is supposed to be local, then don't actually register
3953 it. */
3954 deflt = NULL;
3955 for (t = sinfo->verdefs; t != NULL; t = t->next)
3957 if (t->globals != NULL)
3959 for (d = t->globals; d != NULL; d = d->next)
3961 if ((*d->match) (d, h->root.root.string))
3963 h->verinfo.vertree = t;
3964 break;
3968 if (d != NULL)
3969 break;
3972 if (t->locals != NULL)
3974 for (d = t->locals; d != NULL; d = d->next)
3976 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3977 deflt = t;
3978 else if ((*d->match) (d, h->root.root.string))
3980 h->verinfo.vertree = t;
3981 if (h->dynindx != -1
3982 && info->shared
3983 && ! sinfo->export_dynamic)
3985 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3986 (*bed->elf_backend_hide_symbol) (info, h);
3987 /* FIXME: The name of the symbol has already
3988 been recorded in the dynamic string table
3989 section. */
3991 break;
3995 if (d != NULL)
3996 break;
4000 if (deflt != NULL && h->verinfo.vertree == NULL)
4002 h->verinfo.vertree = deflt;
4003 if (h->dynindx != -1
4004 && info->shared
4005 && ! sinfo->export_dynamic)
4007 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4008 (*bed->elf_backend_hide_symbol) (info, h);
4009 /* FIXME: The name of the symbol has already been
4010 recorded in the dynamic string table section. */
4015 return true;
4018 /* Final phase of ELF linker. */
4020 /* A structure we use to avoid passing large numbers of arguments. */
4022 struct elf_final_link_info
4024 /* General link information. */
4025 struct bfd_link_info *info;
4026 /* Output BFD. */
4027 bfd *output_bfd;
4028 /* Symbol string table. */
4029 struct bfd_strtab_hash *symstrtab;
4030 /* .dynsym section. */
4031 asection *dynsym_sec;
4032 /* .hash section. */
4033 asection *hash_sec;
4034 /* symbol version section (.gnu.version). */
4035 asection *symver_sec;
4036 /* Buffer large enough to hold contents of any section. */
4037 bfd_byte *contents;
4038 /* Buffer large enough to hold external relocs of any section. */
4039 PTR external_relocs;
4040 /* Buffer large enough to hold internal relocs of any section. */
4041 Elf_Internal_Rela *internal_relocs;
4042 /* Buffer large enough to hold external local symbols of any input
4043 BFD. */
4044 Elf_External_Sym *external_syms;
4045 /* Buffer large enough to hold internal local symbols of any input
4046 BFD. */
4047 Elf_Internal_Sym *internal_syms;
4048 /* Array large enough to hold a symbol index for each local symbol
4049 of any input BFD. */
4050 long *indices;
4051 /* Array large enough to hold a section pointer for each local
4052 symbol of any input BFD. */
4053 asection **sections;
4054 /* Buffer to hold swapped out symbols. */
4055 Elf_External_Sym *symbuf;
4056 /* Number of swapped out symbols in buffer. */
4057 size_t symbuf_count;
4058 /* Number of symbols which fit in symbuf. */
4059 size_t symbuf_size;
4062 static boolean elf_link_output_sym
4063 PARAMS ((struct elf_final_link_info *, const char *,
4064 Elf_Internal_Sym *, asection *));
4065 static boolean elf_link_flush_output_syms
4066 PARAMS ((struct elf_final_link_info *));
4067 static boolean elf_link_output_extsym
4068 PARAMS ((struct elf_link_hash_entry *, PTR));
4069 static boolean elf_link_input_bfd
4070 PARAMS ((struct elf_final_link_info *, bfd *));
4071 static boolean elf_reloc_link_order
4072 PARAMS ((bfd *, struct bfd_link_info *, asection *,
4073 struct bfd_link_order *));
4075 /* This struct is used to pass information to elf_link_output_extsym. */
4077 struct elf_outext_info
4079 boolean failed;
4080 boolean localsyms;
4081 struct elf_final_link_info *finfo;
4084 /* Compute the size of, and allocate space for, REL_HDR which is the
4085 section header for a section containing relocations for O. */
4087 static boolean
4088 elf_link_size_reloc_section (abfd, rel_hdr, o)
4089 bfd *abfd;
4090 Elf_Internal_Shdr *rel_hdr;
4091 asection *o;
4093 register struct elf_link_hash_entry **p, **pend;
4094 unsigned reloc_count;
4096 /* Figure out how many relocations there will be. */
4097 if (rel_hdr == &elf_section_data (o)->rel_hdr)
4098 reloc_count = elf_section_data (o)->rel_count;
4099 else
4100 reloc_count = elf_section_data (o)->rel_count2;
4102 /* That allows us to calculate the size of the section. */
4103 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
4105 /* The contents field must last into write_object_contents, so we
4106 allocate it with bfd_alloc rather than malloc. Also since we
4107 cannot be sure that the contents will actually be filled in,
4108 we zero the allocated space. */
4109 rel_hdr->contents = (PTR) bfd_zalloc (abfd, rel_hdr->sh_size);
4110 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
4111 return false;
4113 /* We only allocate one set of hash entries, so we only do it the
4114 first time we are called. */
4115 if (elf_section_data (o)->rel_hashes == NULL)
4117 p = ((struct elf_link_hash_entry **)
4118 bfd_malloc (o->reloc_count
4119 * sizeof (struct elf_link_hash_entry *)));
4120 if (p == NULL && o->reloc_count != 0)
4121 return false;
4123 elf_section_data (o)->rel_hashes = p;
4124 pend = p + o->reloc_count;
4125 for (; p < pend; p++)
4126 *p = NULL;
4129 return true;
4132 /* When performing a relocateable link, the input relocations are
4133 preserved. But, if they reference global symbols, the indices
4134 referenced must be updated. Update all the relocations in
4135 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4137 static void
4138 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4139 bfd *abfd;
4140 Elf_Internal_Shdr *rel_hdr;
4141 unsigned int count;
4142 struct elf_link_hash_entry **rel_hash;
4144 unsigned int i;
4145 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4147 for (i = 0; i < count; i++, rel_hash++)
4149 if (*rel_hash == NULL)
4150 continue;
4152 BFD_ASSERT ((*rel_hash)->indx >= 0);
4154 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4156 Elf_External_Rel *erel;
4157 Elf_Internal_Rel irel;
4159 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4160 if (bed->s->swap_reloc_in)
4161 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, &irel);
4162 else
4163 elf_swap_reloc_in (abfd, erel, &irel);
4164 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
4165 ELF_R_TYPE (irel.r_info));
4166 if (bed->s->swap_reloc_out)
4167 (*bed->s->swap_reloc_out) (abfd, &irel, (bfd_byte *) erel);
4168 else
4169 elf_swap_reloc_out (abfd, &irel, erel);
4171 else
4173 Elf_External_Rela *erela;
4174 Elf_Internal_Rela irela;
4176 BFD_ASSERT (rel_hdr->sh_entsize
4177 == sizeof (Elf_External_Rela));
4179 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4180 if (bed->s->swap_reloca_in)
4181 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, &irela);
4182 else
4183 elf_swap_reloca_in (abfd, erela, &irela);
4184 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4185 ELF_R_TYPE (irela.r_info));
4186 if (bed->s->swap_reloca_out)
4187 (*bed->s->swap_reloca_out) (abfd, &irela, (bfd_byte *) erela);
4188 else
4189 elf_swap_reloca_out (abfd, &irela, erela);
4194 /* Do the final step of an ELF link. */
4196 boolean
4197 elf_bfd_final_link (abfd, info)
4198 bfd *abfd;
4199 struct bfd_link_info *info;
4201 boolean dynamic;
4202 bfd *dynobj;
4203 struct elf_final_link_info finfo;
4204 register asection *o;
4205 register struct bfd_link_order *p;
4206 register bfd *sub;
4207 size_t max_contents_size;
4208 size_t max_external_reloc_size;
4209 size_t max_internal_reloc_count;
4210 size_t max_sym_count;
4211 file_ptr off;
4212 Elf_Internal_Sym elfsym;
4213 unsigned int i;
4214 Elf_Internal_Shdr *symtab_hdr;
4215 Elf_Internal_Shdr *symstrtab_hdr;
4216 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4217 struct elf_outext_info eoinfo;
4219 if (info->shared)
4220 abfd->flags |= DYNAMIC;
4222 dynamic = elf_hash_table (info)->dynamic_sections_created;
4223 dynobj = elf_hash_table (info)->dynobj;
4225 finfo.info = info;
4226 finfo.output_bfd = abfd;
4227 finfo.symstrtab = elf_stringtab_init ();
4228 if (finfo.symstrtab == NULL)
4229 return false;
4231 if (! dynamic)
4233 finfo.dynsym_sec = NULL;
4234 finfo.hash_sec = NULL;
4235 finfo.symver_sec = NULL;
4237 else
4239 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4240 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4241 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4242 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4243 /* Note that it is OK if symver_sec is NULL. */
4246 finfo.contents = NULL;
4247 finfo.external_relocs = NULL;
4248 finfo.internal_relocs = NULL;
4249 finfo.external_syms = NULL;
4250 finfo.internal_syms = NULL;
4251 finfo.indices = NULL;
4252 finfo.sections = NULL;
4253 finfo.symbuf = NULL;
4254 finfo.symbuf_count = 0;
4256 /* Count up the number of relocations we will output for each output
4257 section, so that we know the sizes of the reloc sections. We
4258 also figure out some maximum sizes. */
4259 max_contents_size = 0;
4260 max_external_reloc_size = 0;
4261 max_internal_reloc_count = 0;
4262 max_sym_count = 0;
4263 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4265 o->reloc_count = 0;
4267 for (p = o->link_order_head; p != NULL; p = p->next)
4269 if (p->type == bfd_section_reloc_link_order
4270 || p->type == bfd_symbol_reloc_link_order)
4271 ++o->reloc_count;
4272 else if (p->type == bfd_indirect_link_order)
4274 asection *sec;
4276 sec = p->u.indirect.section;
4278 /* Mark all sections which are to be included in the
4279 link. This will normally be every section. We need
4280 to do this so that we can identify any sections which
4281 the linker has decided to not include. */
4282 sec->linker_mark = true;
4284 if (info->relocateable || info->emitrelocations)
4285 o->reloc_count += sec->reloc_count;
4287 if (sec->_raw_size > max_contents_size)
4288 max_contents_size = sec->_raw_size;
4289 if (sec->_cooked_size > max_contents_size)
4290 max_contents_size = sec->_cooked_size;
4292 /* We are interested in just local symbols, not all
4293 symbols. */
4294 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4295 && (sec->owner->flags & DYNAMIC) == 0)
4297 size_t sym_count;
4299 if (elf_bad_symtab (sec->owner))
4300 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4301 / sizeof (Elf_External_Sym));
4302 else
4303 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4305 if (sym_count > max_sym_count)
4306 max_sym_count = sym_count;
4308 if ((sec->flags & SEC_RELOC) != 0)
4310 size_t ext_size;
4312 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4313 if (ext_size > max_external_reloc_size)
4314 max_external_reloc_size = ext_size;
4315 if (sec->reloc_count > max_internal_reloc_count)
4316 max_internal_reloc_count = sec->reloc_count;
4322 if (o->reloc_count > 0)
4323 o->flags |= SEC_RELOC;
4324 else
4326 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4327 set it (this is probably a bug) and if it is set
4328 assign_section_numbers will create a reloc section. */
4329 o->flags &=~ SEC_RELOC;
4332 /* If the SEC_ALLOC flag is not set, force the section VMA to
4333 zero. This is done in elf_fake_sections as well, but forcing
4334 the VMA to 0 here will ensure that relocs against these
4335 sections are handled correctly. */
4336 if ((o->flags & SEC_ALLOC) == 0
4337 && ! o->user_set_vma)
4338 o->vma = 0;
4341 /* Figure out the file positions for everything but the symbol table
4342 and the relocs. We set symcount to force assign_section_numbers
4343 to create a symbol table. */
4344 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4345 BFD_ASSERT (! abfd->output_has_begun);
4346 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4347 goto error_return;
4349 /* Figure out how many relocations we will have in each section.
4350 Just using RELOC_COUNT isn't good enough since that doesn't
4351 maintain a separate value for REL vs. RELA relocations. */
4352 if (info->relocateable || info->emitrelocations)
4353 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4354 for (o = sub->sections; o != NULL; o = o->next)
4356 asection *output_section;
4358 if (! o->linker_mark)
4360 /* This section was omitted from the link. */
4361 continue;
4364 output_section = o->output_section;
4366 if (output_section != NULL
4367 && (o->flags & SEC_RELOC) != 0)
4369 struct bfd_elf_section_data *esdi
4370 = elf_section_data (o);
4371 struct bfd_elf_section_data *esdo
4372 = elf_section_data (output_section);
4373 unsigned int *rel_count;
4374 unsigned int *rel_count2;
4376 /* We must be careful to add the relocation froms the
4377 input section to the right output count. */
4378 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4380 rel_count = &esdo->rel_count;
4381 rel_count2 = &esdo->rel_count2;
4383 else
4385 rel_count = &esdo->rel_count2;
4386 rel_count2 = &esdo->rel_count;
4389 *rel_count += (esdi->rel_hdr.sh_size
4390 / esdi->rel_hdr.sh_entsize);
4391 if (esdi->rel_hdr2)
4392 *rel_count2 += (esdi->rel_hdr2->sh_size
4393 / esdi->rel_hdr2->sh_entsize);
4397 /* That created the reloc sections. Set their sizes, and assign
4398 them file positions, and allocate some buffers. */
4399 for (o = abfd->sections; o != NULL; o = o->next)
4401 if ((o->flags & SEC_RELOC) != 0)
4403 if (!elf_link_size_reloc_section (abfd,
4404 &elf_section_data (o)->rel_hdr,
4406 goto error_return;
4408 if (elf_section_data (o)->rel_hdr2
4409 && !elf_link_size_reloc_section (abfd,
4410 elf_section_data (o)->rel_hdr2,
4412 goto error_return;
4415 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4416 to count upwards while actually outputting the relocations. */
4417 elf_section_data (o)->rel_count = 0;
4418 elf_section_data (o)->rel_count2 = 0;
4421 _bfd_elf_assign_file_positions_for_relocs (abfd);
4423 /* We have now assigned file positions for all the sections except
4424 .symtab and .strtab. We start the .symtab section at the current
4425 file position, and write directly to it. We build the .strtab
4426 section in memory. */
4427 bfd_get_symcount (abfd) = 0;
4428 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4429 /* sh_name is set in prep_headers. */
4430 symtab_hdr->sh_type = SHT_SYMTAB;
4431 symtab_hdr->sh_flags = 0;
4432 symtab_hdr->sh_addr = 0;
4433 symtab_hdr->sh_size = 0;
4434 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4435 /* sh_link is set in assign_section_numbers. */
4436 /* sh_info is set below. */
4437 /* sh_offset is set just below. */
4438 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4440 off = elf_tdata (abfd)->next_file_pos;
4441 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4443 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4444 incorrect. We do not yet know the size of the .symtab section.
4445 We correct next_file_pos below, after we do know the size. */
4447 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4448 continuously seeking to the right position in the file. */
4449 if (! info->keep_memory || max_sym_count < 20)
4450 finfo.symbuf_size = 20;
4451 else
4452 finfo.symbuf_size = max_sym_count;
4453 finfo.symbuf = ((Elf_External_Sym *)
4454 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4455 if (finfo.symbuf == NULL)
4456 goto error_return;
4458 /* Start writing out the symbol table. The first symbol is always a
4459 dummy symbol. */
4460 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4462 elfsym.st_value = 0;
4463 elfsym.st_size = 0;
4464 elfsym.st_info = 0;
4465 elfsym.st_other = 0;
4466 elfsym.st_shndx = SHN_UNDEF;
4467 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4468 &elfsym, bfd_und_section_ptr))
4469 goto error_return;
4472 #if 0
4473 /* Some standard ELF linkers do this, but we don't because it causes
4474 bootstrap comparison failures. */
4475 /* Output a file symbol for the output file as the second symbol.
4476 We output this even if we are discarding local symbols, although
4477 I'm not sure if this is correct. */
4478 elfsym.st_value = 0;
4479 elfsym.st_size = 0;
4480 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4481 elfsym.st_other = 0;
4482 elfsym.st_shndx = SHN_ABS;
4483 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4484 &elfsym, bfd_abs_section_ptr))
4485 goto error_return;
4486 #endif
4488 /* Output a symbol for each section. We output these even if we are
4489 discarding local symbols, since they are used for relocs. These
4490 symbols have no names. We store the index of each one in the
4491 index field of the section, so that we can find it again when
4492 outputting relocs. */
4493 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4495 elfsym.st_size = 0;
4496 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4497 elfsym.st_other = 0;
4498 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4500 o = section_from_elf_index (abfd, i);
4501 if (o != NULL)
4502 o->target_index = bfd_get_symcount (abfd);
4503 elfsym.st_shndx = i;
4504 if (info->relocateable || o == NULL)
4505 elfsym.st_value = 0;
4506 else
4507 elfsym.st_value = o->vma;
4508 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4509 &elfsym, o))
4510 goto error_return;
4514 /* Allocate some memory to hold information read in from the input
4515 files. */
4516 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4517 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4518 finfo.internal_relocs = ((Elf_Internal_Rela *)
4519 bfd_malloc (max_internal_reloc_count
4520 * sizeof (Elf_Internal_Rela)
4521 * bed->s->int_rels_per_ext_rel));
4522 finfo.external_syms = ((Elf_External_Sym *)
4523 bfd_malloc (max_sym_count
4524 * sizeof (Elf_External_Sym)));
4525 finfo.internal_syms = ((Elf_Internal_Sym *)
4526 bfd_malloc (max_sym_count
4527 * sizeof (Elf_Internal_Sym)));
4528 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4529 finfo.sections = ((asection **)
4530 bfd_malloc (max_sym_count * sizeof (asection *)));
4531 if ((finfo.contents == NULL && max_contents_size != 0)
4532 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4533 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4534 || (finfo.external_syms == NULL && max_sym_count != 0)
4535 || (finfo.internal_syms == NULL && max_sym_count != 0)
4536 || (finfo.indices == NULL && max_sym_count != 0)
4537 || (finfo.sections == NULL && max_sym_count != 0))
4538 goto error_return;
4540 /* Since ELF permits relocations to be against local symbols, we
4541 must have the local symbols available when we do the relocations.
4542 Since we would rather only read the local symbols once, and we
4543 would rather not keep them in memory, we handle all the
4544 relocations for a single input file at the same time.
4546 Unfortunately, there is no way to know the total number of local
4547 symbols until we have seen all of them, and the local symbol
4548 indices precede the global symbol indices. This means that when
4549 we are generating relocateable output, and we see a reloc against
4550 a global symbol, we can not know the symbol index until we have
4551 finished examining all the local symbols to see which ones we are
4552 going to output. To deal with this, we keep the relocations in
4553 memory, and don't output them until the end of the link. This is
4554 an unfortunate waste of memory, but I don't see a good way around
4555 it. Fortunately, it only happens when performing a relocateable
4556 link, which is not the common case. FIXME: If keep_memory is set
4557 we could write the relocs out and then read them again; I don't
4558 know how bad the memory loss will be. */
4560 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4561 sub->output_has_begun = false;
4562 for (o = abfd->sections; o != NULL; o = o->next)
4564 for (p = o->link_order_head; p != NULL; p = p->next)
4566 if (p->type == bfd_indirect_link_order
4567 && (bfd_get_flavour (p->u.indirect.section->owner)
4568 == bfd_target_elf_flavour))
4570 sub = p->u.indirect.section->owner;
4571 if (! sub->output_has_begun)
4573 if (! elf_link_input_bfd (&finfo, sub))
4574 goto error_return;
4575 sub->output_has_begun = true;
4578 else if (p->type == bfd_section_reloc_link_order
4579 || p->type == bfd_symbol_reloc_link_order)
4581 if (! elf_reloc_link_order (abfd, info, o, p))
4582 goto error_return;
4584 else
4586 if (! _bfd_default_link_order (abfd, info, o, p))
4587 goto error_return;
4592 /* That wrote out all the local symbols. Finish up the symbol table
4593 with the global symbols. Even if we want to strip everything we
4594 can, we still need to deal with those global symbols that got
4595 converted to local in a version script. */
4597 if (info->shared)
4599 /* Output any global symbols that got converted to local in a
4600 version script. We do this in a separate step since ELF
4601 requires all local symbols to appear prior to any global
4602 symbols. FIXME: We should only do this if some global
4603 symbols were, in fact, converted to become local. FIXME:
4604 Will this work correctly with the Irix 5 linker? */
4605 eoinfo.failed = false;
4606 eoinfo.finfo = &finfo;
4607 eoinfo.localsyms = true;
4608 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4609 (PTR) &eoinfo);
4610 if (eoinfo.failed)
4611 return false;
4614 /* The sh_info field records the index of the first non local symbol. */
4615 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4617 if (dynamic
4618 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
4620 Elf_Internal_Sym sym;
4621 Elf_External_Sym *dynsym =
4622 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4623 long last_local = 0;
4625 /* Write out the section symbols for the output sections. */
4626 if (info->shared)
4628 asection *s;
4630 sym.st_size = 0;
4631 sym.st_name = 0;
4632 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4633 sym.st_other = 0;
4635 for (s = abfd->sections; s != NULL; s = s->next)
4637 int indx;
4638 indx = elf_section_data (s)->this_idx;
4639 BFD_ASSERT (indx > 0);
4640 sym.st_shndx = indx;
4641 sym.st_value = s->vma;
4643 elf_swap_symbol_out (abfd, &sym,
4644 dynsym + elf_section_data (s)->dynindx);
4647 last_local = bfd_count_sections (abfd);
4650 /* Write out the local dynsyms. */
4651 if (elf_hash_table (info)->dynlocal)
4653 struct elf_link_local_dynamic_entry *e;
4654 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4656 asection *s;
4658 sym.st_size = e->isym.st_size;
4659 sym.st_other = e->isym.st_other;
4661 /* Copy the internal symbol as is.
4662 Note that we saved a word of storage and overwrote
4663 the original st_name with the dynstr_index. */
4664 sym = e->isym;
4666 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4668 s = bfd_section_from_elf_index (e->input_bfd,
4669 e->isym.st_shndx);
4671 sym.st_shndx =
4672 elf_section_data (s->output_section)->this_idx;
4673 sym.st_value = (s->output_section->vma
4674 + s->output_offset
4675 + e->isym.st_value);
4678 if (last_local < e->dynindx)
4679 last_local = e->dynindx;
4681 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4685 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4686 last_local + 1;
4689 /* We get the global symbols from the hash table. */
4690 eoinfo.failed = false;
4691 eoinfo.localsyms = false;
4692 eoinfo.finfo = &finfo;
4693 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4694 (PTR) &eoinfo);
4695 if (eoinfo.failed)
4696 return false;
4698 /* If backend needs to output some symbols not present in the hash
4699 table, do it now. */
4700 if (bed->elf_backend_output_arch_syms)
4702 if (! (*bed->elf_backend_output_arch_syms)
4703 (abfd, info, (PTR) &finfo,
4704 (boolean (*) PARAMS ((PTR, const char *,
4705 Elf_Internal_Sym *, asection *)))
4706 elf_link_output_sym))
4707 return false;
4710 /* Flush all symbols to the file. */
4711 if (! elf_link_flush_output_syms (&finfo))
4712 return false;
4714 /* Now we know the size of the symtab section. */
4715 off += symtab_hdr->sh_size;
4717 /* Finish up and write out the symbol string table (.strtab)
4718 section. */
4719 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4720 /* sh_name was set in prep_headers. */
4721 symstrtab_hdr->sh_type = SHT_STRTAB;
4722 symstrtab_hdr->sh_flags = 0;
4723 symstrtab_hdr->sh_addr = 0;
4724 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4725 symstrtab_hdr->sh_entsize = 0;
4726 symstrtab_hdr->sh_link = 0;
4727 symstrtab_hdr->sh_info = 0;
4728 /* sh_offset is set just below. */
4729 symstrtab_hdr->sh_addralign = 1;
4731 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4732 elf_tdata (abfd)->next_file_pos = off;
4734 if (bfd_get_symcount (abfd) > 0)
4736 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4737 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4738 return false;
4741 /* Adjust the relocs to have the correct symbol indices. */
4742 for (o = abfd->sections; o != NULL; o = o->next)
4744 if ((o->flags & SEC_RELOC) == 0)
4745 continue;
4747 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4748 elf_section_data (o)->rel_count,
4749 elf_section_data (o)->rel_hashes);
4750 if (elf_section_data (o)->rel_hdr2 != NULL)
4751 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4752 elf_section_data (o)->rel_count2,
4753 (elf_section_data (o)->rel_hashes
4754 + elf_section_data (o)->rel_count));
4756 /* Set the reloc_count field to 0 to prevent write_relocs from
4757 trying to swap the relocs out itself. */
4758 o->reloc_count = 0;
4761 /* If we are linking against a dynamic object, or generating a
4762 shared library, finish up the dynamic linking information. */
4763 if (dynamic)
4765 Elf_External_Dyn *dyncon, *dynconend;
4767 /* Fix up .dynamic entries. */
4768 o = bfd_get_section_by_name (dynobj, ".dynamic");
4769 BFD_ASSERT (o != NULL);
4771 dyncon = (Elf_External_Dyn *) o->contents;
4772 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4773 for (; dyncon < dynconend; dyncon++)
4775 Elf_Internal_Dyn dyn;
4776 const char *name;
4777 unsigned int type;
4779 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4781 switch (dyn.d_tag)
4783 default:
4784 break;
4785 case DT_INIT:
4786 name = info->init_function;
4787 goto get_sym;
4788 case DT_FINI:
4789 name = info->fini_function;
4790 get_sym:
4792 struct elf_link_hash_entry *h;
4794 h = elf_link_hash_lookup (elf_hash_table (info), name,
4795 false, false, true);
4796 if (h != NULL
4797 && (h->root.type == bfd_link_hash_defined
4798 || h->root.type == bfd_link_hash_defweak))
4800 dyn.d_un.d_val = h->root.u.def.value;
4801 o = h->root.u.def.section;
4802 if (o->output_section != NULL)
4803 dyn.d_un.d_val += (o->output_section->vma
4804 + o->output_offset);
4805 else
4807 /* The symbol is imported from another shared
4808 library and does not apply to this one. */
4809 dyn.d_un.d_val = 0;
4812 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4815 break;
4817 case DT_HASH:
4818 name = ".hash";
4819 goto get_vma;
4820 case DT_STRTAB:
4821 name = ".dynstr";
4822 goto get_vma;
4823 case DT_SYMTAB:
4824 name = ".dynsym";
4825 goto get_vma;
4826 case DT_VERDEF:
4827 name = ".gnu.version_d";
4828 goto get_vma;
4829 case DT_VERNEED:
4830 name = ".gnu.version_r";
4831 goto get_vma;
4832 case DT_VERSYM:
4833 name = ".gnu.version";
4834 get_vma:
4835 o = bfd_get_section_by_name (abfd, name);
4836 BFD_ASSERT (o != NULL);
4837 dyn.d_un.d_ptr = o->vma;
4838 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4839 break;
4841 case DT_REL:
4842 case DT_RELA:
4843 case DT_RELSZ:
4844 case DT_RELASZ:
4845 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4846 type = SHT_REL;
4847 else
4848 type = SHT_RELA;
4849 dyn.d_un.d_val = 0;
4850 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4852 Elf_Internal_Shdr *hdr;
4854 hdr = elf_elfsections (abfd)[i];
4855 if (hdr->sh_type == type
4856 && (hdr->sh_flags & SHF_ALLOC) != 0)
4858 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4859 dyn.d_un.d_val += hdr->sh_size;
4860 else
4862 if (dyn.d_un.d_val == 0
4863 || hdr->sh_addr < dyn.d_un.d_val)
4864 dyn.d_un.d_val = hdr->sh_addr;
4868 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4869 break;
4874 /* If we have created any dynamic sections, then output them. */
4875 if (dynobj != NULL)
4877 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4878 goto error_return;
4880 for (o = dynobj->sections; o != NULL; o = o->next)
4882 if ((o->flags & SEC_HAS_CONTENTS) == 0
4883 || o->_raw_size == 0
4884 || o->output_section == bfd_abs_section_ptr)
4885 continue;
4886 if ((o->flags & SEC_LINKER_CREATED) == 0)
4888 /* At this point, we are only interested in sections
4889 created by elf_link_create_dynamic_sections. */
4890 continue;
4892 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4893 != SHT_STRTAB)
4894 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4896 if (! bfd_set_section_contents (abfd, o->output_section,
4897 o->contents, o->output_offset,
4898 o->_raw_size))
4899 goto error_return;
4901 else
4903 file_ptr off;
4905 /* The contents of the .dynstr section are actually in a
4906 stringtab. */
4907 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4908 if (bfd_seek (abfd, off, SEEK_SET) != 0
4909 || ! _bfd_stringtab_emit (abfd,
4910 elf_hash_table (info)->dynstr))
4911 goto error_return;
4916 /* If we have optimized stabs strings, output them. */
4917 if (elf_hash_table (info)->stab_info != NULL)
4919 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4920 goto error_return;
4923 if (finfo.symstrtab != NULL)
4924 _bfd_stringtab_free (finfo.symstrtab);
4925 if (finfo.contents != NULL)
4926 free (finfo.contents);
4927 if (finfo.external_relocs != NULL)
4928 free (finfo.external_relocs);
4929 if (finfo.internal_relocs != NULL)
4930 free (finfo.internal_relocs);
4931 if (finfo.external_syms != NULL)
4932 free (finfo.external_syms);
4933 if (finfo.internal_syms != NULL)
4934 free (finfo.internal_syms);
4935 if (finfo.indices != NULL)
4936 free (finfo.indices);
4937 if (finfo.sections != NULL)
4938 free (finfo.sections);
4939 if (finfo.symbuf != NULL)
4940 free (finfo.symbuf);
4941 for (o = abfd->sections; o != NULL; o = o->next)
4943 if ((o->flags & SEC_RELOC) != 0
4944 && elf_section_data (o)->rel_hashes != NULL)
4945 free (elf_section_data (o)->rel_hashes);
4948 elf_tdata (abfd)->linker = true;
4950 return true;
4952 error_return:
4953 if (finfo.symstrtab != NULL)
4954 _bfd_stringtab_free (finfo.symstrtab);
4955 if (finfo.contents != NULL)
4956 free (finfo.contents);
4957 if (finfo.external_relocs != NULL)
4958 free (finfo.external_relocs);
4959 if (finfo.internal_relocs != NULL)
4960 free (finfo.internal_relocs);
4961 if (finfo.external_syms != NULL)
4962 free (finfo.external_syms);
4963 if (finfo.internal_syms != NULL)
4964 free (finfo.internal_syms);
4965 if (finfo.indices != NULL)
4966 free (finfo.indices);
4967 if (finfo.sections != NULL)
4968 free (finfo.sections);
4969 if (finfo.symbuf != NULL)
4970 free (finfo.symbuf);
4971 for (o = abfd->sections; o != NULL; o = o->next)
4973 if ((o->flags & SEC_RELOC) != 0
4974 && elf_section_data (o)->rel_hashes != NULL)
4975 free (elf_section_data (o)->rel_hashes);
4978 return false;
4981 /* Add a symbol to the output symbol table. */
4983 static boolean
4984 elf_link_output_sym (finfo, name, elfsym, input_sec)
4985 struct elf_final_link_info *finfo;
4986 const char *name;
4987 Elf_Internal_Sym *elfsym;
4988 asection *input_sec;
4990 boolean (*output_symbol_hook) PARAMS ((bfd *,
4991 struct bfd_link_info *info,
4992 const char *,
4993 Elf_Internal_Sym *,
4994 asection *));
4996 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4997 elf_backend_link_output_symbol_hook;
4998 if (output_symbol_hook != NULL)
5000 if (! ((*output_symbol_hook)
5001 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
5002 return false;
5005 if (name == (const char *) NULL || *name == '\0')
5006 elfsym->st_name = 0;
5007 else if (input_sec->flags & SEC_EXCLUDE)
5008 elfsym->st_name = 0;
5009 else
5011 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5012 name, true,
5013 false);
5014 if (elfsym->st_name == (unsigned long) -1)
5015 return false;
5018 if (finfo->symbuf_count >= finfo->symbuf_size)
5020 if (! elf_link_flush_output_syms (finfo))
5021 return false;
5024 elf_swap_symbol_out (finfo->output_bfd, elfsym,
5025 (PTR) (finfo->symbuf + finfo->symbuf_count));
5026 ++finfo->symbuf_count;
5028 ++ bfd_get_symcount (finfo->output_bfd);
5030 return true;
5033 /* Flush the output symbols to the file. */
5035 static boolean
5036 elf_link_flush_output_syms (finfo)
5037 struct elf_final_link_info *finfo;
5039 if (finfo->symbuf_count > 0)
5041 Elf_Internal_Shdr *symtab;
5043 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5045 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
5046 SEEK_SET) != 0
5047 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
5048 sizeof (Elf_External_Sym), finfo->output_bfd)
5049 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
5050 return false;
5052 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
5054 finfo->symbuf_count = 0;
5057 return true;
5060 /* Add an external symbol to the symbol table. This is called from
5061 the hash table traversal routine. When generating a shared object,
5062 we go through the symbol table twice. The first time we output
5063 anything that might have been forced to local scope in a version
5064 script. The second time we output the symbols that are still
5065 global symbols. */
5067 static boolean
5068 elf_link_output_extsym (h, data)
5069 struct elf_link_hash_entry *h;
5070 PTR data;
5072 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
5073 struct elf_final_link_info *finfo = eoinfo->finfo;
5074 boolean strip;
5075 Elf_Internal_Sym sym;
5076 asection *input_sec;
5078 /* Decide whether to output this symbol in this pass. */
5079 if (eoinfo->localsyms)
5081 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5082 return true;
5084 else
5086 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5087 return true;
5090 /* If we are not creating a shared library, and this symbol is
5091 referenced by a shared library but is not defined anywhere, then
5092 warn that it is undefined. If we do not do this, the runtime
5093 linker will complain that the symbol is undefined when the
5094 program is run. We don't have to worry about symbols that are
5095 referenced by regular files, because we will already have issued
5096 warnings for them. */
5097 if (! finfo->info->relocateable
5098 && ! finfo->info->allow_shlib_undefined
5099 && ! (finfo->info->shared
5100 && !finfo->info->no_undefined)
5101 && h->root.type == bfd_link_hash_undefined
5102 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
5103 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5105 if (! ((*finfo->info->callbacks->undefined_symbol)
5106 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
5107 (asection *) NULL, 0, true)))
5109 eoinfo->failed = true;
5110 return false;
5114 /* We don't want to output symbols that have never been mentioned by
5115 a regular file, or that we have been told to strip. However, if
5116 h->indx is set to -2, the symbol is used by a reloc and we must
5117 output it. */
5118 if (h->indx == -2)
5119 strip = false;
5120 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
5121 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
5122 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
5123 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5124 strip = true;
5125 else if (finfo->info->strip == strip_all
5126 || (finfo->info->strip == strip_some
5127 && bfd_hash_lookup (finfo->info->keep_hash,
5128 h->root.root.string,
5129 false, false) == NULL))
5130 strip = true;
5131 else
5132 strip = false;
5134 /* If we're stripping it, and it's not a dynamic symbol, there's
5135 nothing else to do unless it is a forced local symbol. */
5136 if (strip
5137 && h->dynindx == -1
5138 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5139 return true;
5141 sym.st_value = 0;
5142 sym.st_size = h->size;
5143 sym.st_other = h->other;
5144 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5145 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5146 else if (h->root.type == bfd_link_hash_undefweak
5147 || h->root.type == bfd_link_hash_defweak)
5148 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5149 else
5150 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5152 switch (h->root.type)
5154 default:
5155 case bfd_link_hash_new:
5156 abort ();
5157 return false;
5159 case bfd_link_hash_undefined:
5160 input_sec = bfd_und_section_ptr;
5161 sym.st_shndx = SHN_UNDEF;
5162 break;
5164 case bfd_link_hash_undefweak:
5165 input_sec = bfd_und_section_ptr;
5166 sym.st_shndx = SHN_UNDEF;
5167 break;
5169 case bfd_link_hash_defined:
5170 case bfd_link_hash_defweak:
5172 input_sec = h->root.u.def.section;
5173 if (input_sec->output_section != NULL)
5175 sym.st_shndx =
5176 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5177 input_sec->output_section);
5178 if (sym.st_shndx == (unsigned short) -1)
5180 (*_bfd_error_handler)
5181 (_("%s: could not find output section %s for input section %s"),
5182 bfd_get_filename (finfo->output_bfd),
5183 input_sec->output_section->name,
5184 input_sec->name);
5185 eoinfo->failed = true;
5186 return false;
5189 /* ELF symbols in relocateable files are section relative,
5190 but in nonrelocateable files they are virtual
5191 addresses. */
5192 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5193 if (! finfo->info->relocateable)
5194 sym.st_value += input_sec->output_section->vma;
5196 else
5198 BFD_ASSERT (input_sec->owner == NULL
5199 || (input_sec->owner->flags & DYNAMIC) != 0);
5200 sym.st_shndx = SHN_UNDEF;
5201 input_sec = bfd_und_section_ptr;
5204 break;
5206 case bfd_link_hash_common:
5207 input_sec = h->root.u.c.p->section;
5208 sym.st_shndx = SHN_COMMON;
5209 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5210 break;
5212 case bfd_link_hash_indirect:
5213 /* These symbols are created by symbol versioning. They point
5214 to the decorated version of the name. For example, if the
5215 symbol foo@@GNU_1.2 is the default, which should be used when
5216 foo is used with no version, then we add an indirect symbol
5217 foo which points to foo@@GNU_1.2. We ignore these symbols,
5218 since the indirected symbol is already in the hash table. */
5219 return true;
5221 case bfd_link_hash_warning:
5222 /* We can't represent these symbols in ELF, although a warning
5223 symbol may have come from a .gnu.warning.SYMBOL section. We
5224 just put the target symbol in the hash table. If the target
5225 symbol does not really exist, don't do anything. */
5226 if (h->root.u.i.link->type == bfd_link_hash_new)
5227 return true;
5228 return (elf_link_output_extsym
5229 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5232 /* Give the processor backend a chance to tweak the symbol value,
5233 and also to finish up anything that needs to be done for this
5234 symbol. */
5235 if ((h->dynindx != -1
5236 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5237 && elf_hash_table (finfo->info)->dynamic_sections_created)
5239 struct elf_backend_data *bed;
5241 bed = get_elf_backend_data (finfo->output_bfd);
5242 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5243 (finfo->output_bfd, finfo->info, h, &sym)))
5245 eoinfo->failed = true;
5246 return false;
5250 /* If we are marking the symbol as undefined, and there are no
5251 non-weak references to this symbol from a regular object, then
5252 mark the symbol as weak undefined; if there are non-weak
5253 references, mark the symbol as strong. We can't do this earlier,
5254 because it might not be marked as undefined until the
5255 finish_dynamic_symbol routine gets through with it. */
5256 if (sym.st_shndx == SHN_UNDEF
5257 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5258 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5259 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5261 int bindtype;
5263 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5264 bindtype = STB_GLOBAL;
5265 else
5266 bindtype = STB_WEAK;
5267 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5270 /* If a symbol is not defined locally, we clear the visibility
5271 field. */
5272 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5273 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5275 /* If this symbol should be put in the .dynsym section, then put it
5276 there now. We have already know the symbol index. We also fill
5277 in the entry in the .hash section. */
5278 if (h->dynindx != -1
5279 && elf_hash_table (finfo->info)->dynamic_sections_created)
5281 size_t bucketcount;
5282 size_t bucket;
5283 size_t hash_entry_size;
5284 bfd_byte *bucketpos;
5285 bfd_vma chain;
5287 sym.st_name = h->dynstr_index;
5289 elf_swap_symbol_out (finfo->output_bfd, &sym,
5290 (PTR) (((Elf_External_Sym *)
5291 finfo->dynsym_sec->contents)
5292 + h->dynindx));
5294 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5295 bucket = h->elf_hash_value % bucketcount;
5296 hash_entry_size
5297 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5298 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5299 + (bucket + 2) * hash_entry_size);
5300 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5301 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5302 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5303 ((bfd_byte *) finfo->hash_sec->contents
5304 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5306 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5308 Elf_Internal_Versym iversym;
5310 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5312 if (h->verinfo.verdef == NULL)
5313 iversym.vs_vers = 0;
5314 else
5315 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5317 else
5319 if (h->verinfo.vertree == NULL)
5320 iversym.vs_vers = 1;
5321 else
5322 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5325 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5326 iversym.vs_vers |= VERSYM_HIDDEN;
5328 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5329 (((Elf_External_Versym *)
5330 finfo->symver_sec->contents)
5331 + h->dynindx));
5335 /* If we're stripping it, then it was just a dynamic symbol, and
5336 there's nothing else to do. */
5337 if (strip)
5338 return true;
5340 h->indx = bfd_get_symcount (finfo->output_bfd);
5342 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5344 eoinfo->failed = true;
5345 return false;
5348 return true;
5351 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5352 originated from the section given by INPUT_REL_HDR) to the
5353 OUTPUT_BFD. */
5355 static void
5356 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5357 internal_relocs)
5358 bfd *output_bfd;
5359 asection *input_section;
5360 Elf_Internal_Shdr *input_rel_hdr;
5361 Elf_Internal_Rela *internal_relocs;
5363 Elf_Internal_Rela *irela;
5364 Elf_Internal_Rela *irelaend;
5365 Elf_Internal_Shdr *output_rel_hdr;
5366 asection *output_section;
5367 unsigned int *rel_countp = NULL;
5368 struct elf_backend_data *bed;
5370 output_section = input_section->output_section;
5371 output_rel_hdr = NULL;
5373 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5374 == input_rel_hdr->sh_entsize)
5376 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5377 rel_countp = &elf_section_data (output_section)->rel_count;
5379 else if (elf_section_data (output_section)->rel_hdr2
5380 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5381 == input_rel_hdr->sh_entsize))
5383 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5384 rel_countp = &elf_section_data (output_section)->rel_count2;
5387 BFD_ASSERT (output_rel_hdr != NULL);
5389 bed = get_elf_backend_data (output_bfd);
5390 irela = internal_relocs;
5391 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5392 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5394 Elf_External_Rel *erel;
5396 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5397 for (; irela < irelaend; irela++, erel++)
5399 Elf_Internal_Rel irel;
5401 irel.r_offset = irela->r_offset;
5402 irel.r_info = irela->r_info;
5403 BFD_ASSERT (irela->r_addend == 0);
5404 if (bed->s->swap_reloc_out)
5405 (*bed->s->swap_reloc_out) (output_bfd, &irel, (PTR) erel);
5406 else
5407 elf_swap_reloc_out (output_bfd, &irel, erel);
5410 else
5412 Elf_External_Rela *erela;
5414 BFD_ASSERT (input_rel_hdr->sh_entsize
5415 == sizeof (Elf_External_Rela));
5416 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5417 for (; irela < irelaend; irela++, erela++)
5418 if (bed->s->swap_reloca_out)
5419 (*bed->s->swap_reloca_out) (output_bfd, irela, (PTR) erela);
5420 else
5421 elf_swap_reloca_out (output_bfd, irela, erela);
5424 /* Bump the counter, so that we know where to add the next set of
5425 relocations. */
5426 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5429 /* Link an input file into the linker output file. This function
5430 handles all the sections and relocations of the input file at once.
5431 This is so that we only have to read the local symbols once, and
5432 don't have to keep them in memory. */
5434 static boolean
5435 elf_link_input_bfd (finfo, input_bfd)
5436 struct elf_final_link_info *finfo;
5437 bfd *input_bfd;
5439 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5440 bfd *, asection *, bfd_byte *,
5441 Elf_Internal_Rela *,
5442 Elf_Internal_Sym *, asection **));
5443 bfd *output_bfd;
5444 Elf_Internal_Shdr *symtab_hdr;
5445 size_t locsymcount;
5446 size_t extsymoff;
5447 Elf_External_Sym *external_syms;
5448 Elf_External_Sym *esym;
5449 Elf_External_Sym *esymend;
5450 Elf_Internal_Sym *isym;
5451 long *pindex;
5452 asection **ppsection;
5453 asection *o;
5454 struct elf_backend_data *bed;
5456 output_bfd = finfo->output_bfd;
5457 bed = get_elf_backend_data (output_bfd);
5458 relocate_section = bed->elf_backend_relocate_section;
5460 /* If this is a dynamic object, we don't want to do anything here:
5461 we don't want the local symbols, and we don't want the section
5462 contents. */
5463 if ((input_bfd->flags & DYNAMIC) != 0)
5464 return true;
5466 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5467 if (elf_bad_symtab (input_bfd))
5469 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5470 extsymoff = 0;
5472 else
5474 locsymcount = symtab_hdr->sh_info;
5475 extsymoff = symtab_hdr->sh_info;
5478 /* Read the local symbols. */
5479 if (symtab_hdr->contents != NULL)
5480 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5481 else if (locsymcount == 0)
5482 external_syms = NULL;
5483 else
5485 external_syms = finfo->external_syms;
5486 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5487 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5488 locsymcount, input_bfd)
5489 != locsymcount * sizeof (Elf_External_Sym)))
5490 return false;
5493 /* Swap in the local symbols and write out the ones which we know
5494 are going into the output file. */
5495 esym = external_syms;
5496 esymend = esym + locsymcount;
5497 isym = finfo->internal_syms;
5498 pindex = finfo->indices;
5499 ppsection = finfo->sections;
5500 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5502 asection *isec;
5503 const char *name;
5504 Elf_Internal_Sym osym;
5506 elf_swap_symbol_in (input_bfd, esym, isym);
5507 *pindex = -1;
5509 if (elf_bad_symtab (input_bfd))
5511 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5513 *ppsection = NULL;
5514 continue;
5518 if (isym->st_shndx == SHN_UNDEF)
5519 isec = bfd_und_section_ptr;
5520 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5521 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5522 else if (isym->st_shndx == SHN_ABS)
5523 isec = bfd_abs_section_ptr;
5524 else if (isym->st_shndx == SHN_COMMON)
5525 isec = bfd_com_section_ptr;
5526 else
5528 /* Who knows? */
5529 isec = NULL;
5532 *ppsection = isec;
5534 /* Don't output the first, undefined, symbol. */
5535 if (esym == external_syms)
5536 continue;
5538 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5540 asection *ksec;
5542 /* Save away all section symbol values. */
5543 if (isec != NULL)
5544 isec->symbol->value = isym->st_value;
5546 /* If this is a discarded link-once section symbol, update
5547 it's value to that of the kept section symbol. The
5548 linker will keep the first of any matching link-once
5549 sections, so we should have already seen it's section
5550 symbol. I trust no-one will have the bright idea of
5551 re-ordering the bfd list... */
5552 if (isec != NULL
5553 && (bfd_get_section_flags (input_bfd, isec) & SEC_LINK_ONCE) != 0
5554 && (ksec = isec->kept_section) != NULL)
5556 isym->st_value = ksec->symbol->value;
5558 /* That put the value right, but the section info is all
5559 wrong. I hope this works. */
5560 isec->output_offset = ksec->output_offset;
5561 isec->output_section = ksec->output_section;
5564 /* We never output section symbols. Instead, we use the
5565 section symbol of the corresponding section in the output
5566 file. */
5567 continue;
5570 /* If we are stripping all symbols, we don't want to output this
5571 one. */
5572 if (finfo->info->strip == strip_all)
5573 continue;
5575 /* If we are discarding all local symbols, we don't want to
5576 output this one. If we are generating a relocateable output
5577 file, then some of the local symbols may be required by
5578 relocs; we output them below as we discover that they are
5579 needed. */
5580 if (finfo->info->discard == discard_all)
5581 continue;
5583 /* If this symbol is defined in a section which we are
5584 discarding, we don't need to keep it, but note that
5585 linker_mark is only reliable for sections that have contents.
5586 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5587 as well as linker_mark. */
5588 if (isym->st_shndx > 0
5589 && isym->st_shndx < SHN_LORESERVE
5590 && isec != NULL
5591 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5592 || (! finfo->info->relocateable
5593 && (isec->flags & SEC_EXCLUDE) != 0)))
5594 continue;
5596 /* Get the name of the symbol. */
5597 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5598 isym->st_name);
5599 if (name == NULL)
5600 return false;
5602 /* See if we are discarding symbols with this name. */
5603 if ((finfo->info->strip == strip_some
5604 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5605 == NULL))
5606 || (finfo->info->discard == discard_l
5607 && bfd_is_local_label_name (input_bfd, name)))
5608 continue;
5610 /* If we get here, we are going to output this symbol. */
5612 osym = *isym;
5614 /* Adjust the section index for the output file. */
5615 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5616 isec->output_section);
5617 if (osym.st_shndx == (unsigned short) -1)
5618 return false;
5620 *pindex = bfd_get_symcount (output_bfd);
5622 /* ELF symbols in relocateable files are section relative, but
5623 in executable files they are virtual addresses. Note that
5624 this code assumes that all ELF sections have an associated
5625 BFD section with a reasonable value for output_offset; below
5626 we assume that they also have a reasonable value for
5627 output_section. Any special sections must be set up to meet
5628 these requirements. */
5629 osym.st_value += isec->output_offset;
5630 if (! finfo->info->relocateable)
5631 osym.st_value += isec->output_section->vma;
5633 if (! elf_link_output_sym (finfo, name, &osym, isec))
5634 return false;
5637 /* Relocate the contents of each section. */
5638 for (o = input_bfd->sections; o != NULL; o = o->next)
5640 bfd_byte *contents;
5642 if (! o->linker_mark)
5644 /* This section was omitted from the link. */
5645 continue;
5648 if ((o->flags & SEC_HAS_CONTENTS) == 0
5649 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5650 continue;
5652 if ((o->flags & SEC_LINKER_CREATED) != 0)
5654 /* Section was created by elf_link_create_dynamic_sections
5655 or somesuch. */
5656 continue;
5659 /* Get the contents of the section. They have been cached by a
5660 relaxation routine. Note that o is a section in an input
5661 file, so the contents field will not have been set by any of
5662 the routines which work on output files. */
5663 if (elf_section_data (o)->this_hdr.contents != NULL)
5664 contents = elf_section_data (o)->this_hdr.contents;
5665 else
5667 contents = finfo->contents;
5668 if (! bfd_get_section_contents (input_bfd, o, contents,
5669 (file_ptr) 0, o->_raw_size))
5670 return false;
5673 if ((o->flags & SEC_RELOC) != 0)
5675 Elf_Internal_Rela *internal_relocs;
5677 /* Get the swapped relocs. */
5678 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5679 (input_bfd, o, finfo->external_relocs,
5680 finfo->internal_relocs, false));
5681 if (internal_relocs == NULL
5682 && o->reloc_count > 0)
5683 return false;
5685 /* Relocate the section by invoking a back end routine.
5687 The back end routine is responsible for adjusting the
5688 section contents as necessary, and (if using Rela relocs
5689 and generating a relocateable output file) adjusting the
5690 reloc addend as necessary.
5692 The back end routine does not have to worry about setting
5693 the reloc address or the reloc symbol index.
5695 The back end routine is given a pointer to the swapped in
5696 internal symbols, and can access the hash table entries
5697 for the external symbols via elf_sym_hashes (input_bfd).
5699 When generating relocateable output, the back end routine
5700 must handle STB_LOCAL/STT_SECTION symbols specially. The
5701 output symbol is going to be a section symbol
5702 corresponding to the output section, which will require
5703 the addend to be adjusted. */
5705 if (! (*relocate_section) (output_bfd, finfo->info,
5706 input_bfd, o, contents,
5707 internal_relocs,
5708 finfo->internal_syms,
5709 finfo->sections))
5710 return false;
5712 if (finfo->info->relocateable || finfo->info->emitrelocations)
5714 Elf_Internal_Rela *irela;
5715 Elf_Internal_Rela *irelaend;
5716 struct elf_link_hash_entry **rel_hash;
5717 Elf_Internal_Shdr *input_rel_hdr;
5719 /* Adjust the reloc addresses and symbol indices. */
5721 irela = internal_relocs;
5722 irelaend =
5723 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5724 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5725 + elf_section_data (o->output_section)->rel_count
5726 + elf_section_data (o->output_section)->rel_count2);
5727 for (; irela < irelaend; irela++, rel_hash++)
5729 unsigned long r_symndx;
5730 Elf_Internal_Sym *isym;
5731 asection *sec;
5733 irela->r_offset += o->output_offset;
5735 /* Relocs in an executable have to be virtual addresses. */
5736 if (finfo->info->emitrelocations)
5737 irela->r_offset += o->output_section->vma;
5739 r_symndx = ELF_R_SYM (irela->r_info);
5741 if (r_symndx == 0)
5742 continue;
5744 if (r_symndx >= locsymcount
5745 || (elf_bad_symtab (input_bfd)
5746 && finfo->sections[r_symndx] == NULL))
5748 struct elf_link_hash_entry *rh;
5749 long indx;
5751 /* This is a reloc against a global symbol. We
5752 have not yet output all the local symbols, so
5753 we do not know the symbol index of any global
5754 symbol. We set the rel_hash entry for this
5755 reloc to point to the global hash table entry
5756 for this symbol. The symbol index is then
5757 set at the end of elf_bfd_final_link. */
5758 indx = r_symndx - extsymoff;
5759 rh = elf_sym_hashes (input_bfd)[indx];
5760 while (rh->root.type == bfd_link_hash_indirect
5761 || rh->root.type == bfd_link_hash_warning)
5762 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5764 /* Setting the index to -2 tells
5765 elf_link_output_extsym that this symbol is
5766 used by a reloc. */
5767 BFD_ASSERT (rh->indx < 0);
5768 rh->indx = -2;
5770 *rel_hash = rh;
5772 continue;
5775 /* This is a reloc against a local symbol. */
5777 *rel_hash = NULL;
5778 isym = finfo->internal_syms + r_symndx;
5779 sec = finfo->sections[r_symndx];
5780 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5782 /* I suppose the backend ought to fill in the
5783 section of any STT_SECTION symbol against a
5784 processor specific section. If we have
5785 discarded a section, the output_section will
5786 be the absolute section. */
5787 if (sec != NULL
5788 && (bfd_is_abs_section (sec)
5789 || (sec->output_section != NULL
5790 && bfd_is_abs_section (sec->output_section))))
5791 r_symndx = 0;
5792 else if (sec == NULL || sec->owner == NULL)
5794 bfd_set_error (bfd_error_bad_value);
5795 return false;
5797 else
5799 r_symndx = sec->output_section->target_index;
5800 BFD_ASSERT (r_symndx != 0);
5803 else
5805 if (finfo->indices[r_symndx] == -1)
5807 unsigned long link;
5808 const char *name;
5809 asection *osec;
5811 if (finfo->info->strip == strip_all)
5813 /* You can't do ld -r -s. */
5814 bfd_set_error (bfd_error_invalid_operation);
5815 return false;
5818 /* This symbol was skipped earlier, but
5819 since it is needed by a reloc, we
5820 must output it now. */
5821 link = symtab_hdr->sh_link;
5822 name = bfd_elf_string_from_elf_section (input_bfd,
5823 link,
5824 isym->st_name);
5825 if (name == NULL)
5826 return false;
5828 osec = sec->output_section;
5829 isym->st_shndx =
5830 _bfd_elf_section_from_bfd_section (output_bfd,
5831 osec);
5832 if (isym->st_shndx == (unsigned short) -1)
5833 return false;
5835 isym->st_value += sec->output_offset;
5836 if (! finfo->info->relocateable)
5837 isym->st_value += osec->vma;
5839 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5841 if (! elf_link_output_sym (finfo, name, isym, sec))
5842 return false;
5845 r_symndx = finfo->indices[r_symndx];
5848 irela->r_info = ELF_R_INFO (r_symndx,
5849 ELF_R_TYPE (irela->r_info));
5852 /* Swap out the relocs. */
5853 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5854 elf_link_output_relocs (output_bfd, o,
5855 input_rel_hdr,
5856 internal_relocs);
5857 internal_relocs
5858 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5859 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5860 if (input_rel_hdr)
5861 elf_link_output_relocs (output_bfd, o,
5862 input_rel_hdr,
5863 internal_relocs);
5867 /* Write out the modified section contents. */
5868 if (elf_section_data (o)->stab_info == NULL)
5870 if (! (o->flags & SEC_EXCLUDE) &&
5871 ! bfd_set_section_contents (output_bfd, o->output_section,
5872 contents, o->output_offset,
5873 (o->_cooked_size != 0
5874 ? o->_cooked_size
5875 : o->_raw_size)))
5876 return false;
5878 else
5880 if (! (_bfd_write_section_stabs
5881 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5882 o, &elf_section_data (o)->stab_info, contents)))
5883 return false;
5887 return true;
5890 /* Generate a reloc when linking an ELF file. This is a reloc
5891 requested by the linker, and does come from any input file. This
5892 is used to build constructor and destructor tables when linking
5893 with -Ur. */
5895 static boolean
5896 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5897 bfd *output_bfd;
5898 struct bfd_link_info *info;
5899 asection *output_section;
5900 struct bfd_link_order *link_order;
5902 reloc_howto_type *howto;
5903 long indx;
5904 bfd_vma offset;
5905 bfd_vma addend;
5906 struct elf_link_hash_entry **rel_hash_ptr;
5907 Elf_Internal_Shdr *rel_hdr;
5908 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
5910 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5911 if (howto == NULL)
5913 bfd_set_error (bfd_error_bad_value);
5914 return false;
5917 addend = link_order->u.reloc.p->addend;
5919 /* Figure out the symbol index. */
5920 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5921 + elf_section_data (output_section)->rel_count
5922 + elf_section_data (output_section)->rel_count2);
5923 if (link_order->type == bfd_section_reloc_link_order)
5925 indx = link_order->u.reloc.p->u.section->target_index;
5926 BFD_ASSERT (indx != 0);
5927 *rel_hash_ptr = NULL;
5929 else
5931 struct elf_link_hash_entry *h;
5933 /* Treat a reloc against a defined symbol as though it were
5934 actually against the section. */
5935 h = ((struct elf_link_hash_entry *)
5936 bfd_wrapped_link_hash_lookup (output_bfd, info,
5937 link_order->u.reloc.p->u.name,
5938 false, false, true));
5939 if (h != NULL
5940 && (h->root.type == bfd_link_hash_defined
5941 || h->root.type == bfd_link_hash_defweak))
5943 asection *section;
5945 section = h->root.u.def.section;
5946 indx = section->output_section->target_index;
5947 *rel_hash_ptr = NULL;
5948 /* It seems that we ought to add the symbol value to the
5949 addend here, but in practice it has already been added
5950 because it was passed to constructor_callback. */
5951 addend += section->output_section->vma + section->output_offset;
5953 else if (h != NULL)
5955 /* Setting the index to -2 tells elf_link_output_extsym that
5956 this symbol is used by a reloc. */
5957 h->indx = -2;
5958 *rel_hash_ptr = h;
5959 indx = 0;
5961 else
5963 if (! ((*info->callbacks->unattached_reloc)
5964 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5965 (asection *) NULL, (bfd_vma) 0)))
5966 return false;
5967 indx = 0;
5971 /* If this is an inplace reloc, we must write the addend into the
5972 object file. */
5973 if (howto->partial_inplace && addend != 0)
5975 bfd_size_type size;
5976 bfd_reloc_status_type rstat;
5977 bfd_byte *buf;
5978 boolean ok;
5980 size = bfd_get_reloc_size (howto);
5981 buf = (bfd_byte *) bfd_zmalloc (size);
5982 if (buf == (bfd_byte *) NULL)
5983 return false;
5984 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5985 switch (rstat)
5987 case bfd_reloc_ok:
5988 break;
5989 default:
5990 case bfd_reloc_outofrange:
5991 abort ();
5992 case bfd_reloc_overflow:
5993 if (! ((*info->callbacks->reloc_overflow)
5994 (info,
5995 (link_order->type == bfd_section_reloc_link_order
5996 ? bfd_section_name (output_bfd,
5997 link_order->u.reloc.p->u.section)
5998 : link_order->u.reloc.p->u.name),
5999 howto->name, addend, (bfd *) NULL, (asection *) NULL,
6000 (bfd_vma) 0)))
6002 free (buf);
6003 return false;
6005 break;
6007 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
6008 (file_ptr) link_order->offset, size);
6009 free (buf);
6010 if (! ok)
6011 return false;
6014 /* The address of a reloc is relative to the section in a
6015 relocateable file, and is a virtual address in an executable
6016 file. */
6017 offset = link_order->offset;
6018 if (! info->relocateable)
6019 offset += output_section->vma;
6021 rel_hdr = &elf_section_data (output_section)->rel_hdr;
6023 if (rel_hdr->sh_type == SHT_REL)
6025 Elf_Internal_Rel irel;
6026 Elf_External_Rel *erel;
6028 irel.r_offset = offset;
6029 irel.r_info = ELF_R_INFO (indx, howto->type);
6030 erel = ((Elf_External_Rel *) rel_hdr->contents
6031 + elf_section_data (output_section)->rel_count);
6032 if (bed->s->swap_reloc_out)
6033 (*bed->s->swap_reloc_out) (output_bfd, &irel, (bfd_byte *) erel);
6034 else
6035 elf_swap_reloc_out (output_bfd, &irel, erel);
6037 else
6039 Elf_Internal_Rela irela;
6040 Elf_External_Rela *erela;
6042 irela.r_offset = offset;
6043 irela.r_info = ELF_R_INFO (indx, howto->type);
6044 irela.r_addend = addend;
6045 erela = ((Elf_External_Rela *) rel_hdr->contents
6046 + elf_section_data (output_section)->rel_count);
6047 if (bed->s->swap_reloca_out)
6048 (*bed->s->swap_reloca_out) (output_bfd, &irela, (bfd_byte *) erela);
6049 else
6050 elf_swap_reloca_out (output_bfd, &irela, erela);
6053 ++elf_section_data (output_section)->rel_count;
6055 return true;
6058 /* Allocate a pointer to live in a linker created section. */
6060 boolean
6061 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6062 bfd *abfd;
6063 struct bfd_link_info *info;
6064 elf_linker_section_t *lsect;
6065 struct elf_link_hash_entry *h;
6066 const Elf_Internal_Rela *rel;
6068 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6069 elf_linker_section_pointers_t *linker_section_ptr;
6070 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6072 BFD_ASSERT (lsect != NULL);
6074 /* Is this a global symbol? */
6075 if (h != NULL)
6077 /* Has this symbol already been allocated, if so, our work is done */
6078 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6079 rel->r_addend,
6080 lsect->which))
6081 return true;
6083 ptr_linker_section_ptr = &h->linker_section_pointer;
6084 /* Make sure this symbol is output as a dynamic symbol. */
6085 if (h->dynindx == -1)
6087 if (! elf_link_record_dynamic_symbol (info, h))
6088 return false;
6091 if (lsect->rel_section)
6092 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6095 else /* Allocation of a pointer to a local symbol */
6097 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6099 /* Allocate a table to hold the local symbols if first time */
6100 if (!ptr)
6102 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6103 register unsigned int i;
6105 ptr = (elf_linker_section_pointers_t **)
6106 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6108 if (!ptr)
6109 return false;
6111 elf_local_ptr_offsets (abfd) = ptr;
6112 for (i = 0; i < num_symbols; i++)
6113 ptr[i] = (elf_linker_section_pointers_t *)0;
6116 /* Has this symbol already been allocated, if so, our work is done */
6117 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6118 rel->r_addend,
6119 lsect->which))
6120 return true;
6122 ptr_linker_section_ptr = &ptr[r_symndx];
6124 if (info->shared)
6126 /* If we are generating a shared object, we need to
6127 output a R_<xxx>_RELATIVE reloc so that the
6128 dynamic linker can adjust this GOT entry. */
6129 BFD_ASSERT (lsect->rel_section != NULL);
6130 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6134 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6135 from internal memory. */
6136 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6137 linker_section_ptr = (elf_linker_section_pointers_t *)
6138 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6140 if (!linker_section_ptr)
6141 return false;
6143 linker_section_ptr->next = *ptr_linker_section_ptr;
6144 linker_section_ptr->addend = rel->r_addend;
6145 linker_section_ptr->which = lsect->which;
6146 linker_section_ptr->written_address_p = false;
6147 *ptr_linker_section_ptr = linker_section_ptr;
6149 #if 0
6150 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6152 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6153 lsect->hole_offset += ARCH_SIZE / 8;
6154 lsect->sym_offset += ARCH_SIZE / 8;
6155 if (lsect->sym_hash) /* Bump up symbol value if needed */
6157 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6158 #ifdef DEBUG
6159 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6160 lsect->sym_hash->root.root.string,
6161 (long)ARCH_SIZE / 8,
6162 (long)lsect->sym_hash->root.u.def.value);
6163 #endif
6166 else
6167 #endif
6168 linker_section_ptr->offset = lsect->section->_raw_size;
6170 lsect->section->_raw_size += ARCH_SIZE / 8;
6172 #ifdef DEBUG
6173 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6174 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6175 #endif
6177 return true;
6180 #if ARCH_SIZE==64
6181 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6182 #endif
6183 #if ARCH_SIZE==32
6184 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6185 #endif
6187 /* Fill in the address for a pointer generated in alinker section. */
6189 bfd_vma
6190 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6191 bfd *output_bfd;
6192 bfd *input_bfd;
6193 struct bfd_link_info *info;
6194 elf_linker_section_t *lsect;
6195 struct elf_link_hash_entry *h;
6196 bfd_vma relocation;
6197 const Elf_Internal_Rela *rel;
6198 int relative_reloc;
6200 elf_linker_section_pointers_t *linker_section_ptr;
6202 BFD_ASSERT (lsect != NULL);
6204 if (h != NULL) /* global symbol */
6206 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6207 rel->r_addend,
6208 lsect->which);
6210 BFD_ASSERT (linker_section_ptr != NULL);
6212 if (! elf_hash_table (info)->dynamic_sections_created
6213 || (info->shared
6214 && info->symbolic
6215 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6217 /* This is actually a static link, or it is a
6218 -Bsymbolic link and the symbol is defined
6219 locally. We must initialize this entry in the
6220 global section.
6222 When doing a dynamic link, we create a .rela.<xxx>
6223 relocation entry to initialize the value. This
6224 is done in the finish_dynamic_symbol routine. */
6225 if (!linker_section_ptr->written_address_p)
6227 linker_section_ptr->written_address_p = true;
6228 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6229 lsect->section->contents + linker_section_ptr->offset);
6233 else /* local symbol */
6235 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6236 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6237 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6238 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6239 rel->r_addend,
6240 lsect->which);
6242 BFD_ASSERT (linker_section_ptr != NULL);
6244 /* Write out pointer if it hasn't been rewritten out before */
6245 if (!linker_section_ptr->written_address_p)
6247 linker_section_ptr->written_address_p = true;
6248 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6249 lsect->section->contents + linker_section_ptr->offset);
6251 if (info->shared)
6253 asection *srel = lsect->rel_section;
6254 Elf_Internal_Rela outrel;
6256 /* We need to generate a relative reloc for the dynamic linker. */
6257 if (!srel)
6258 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6259 lsect->rel_name);
6261 BFD_ASSERT (srel != NULL);
6263 outrel.r_offset = (lsect->section->output_section->vma
6264 + lsect->section->output_offset
6265 + linker_section_ptr->offset);
6266 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6267 outrel.r_addend = 0;
6268 elf_swap_reloca_out (output_bfd, &outrel,
6269 (((Elf_External_Rela *)
6270 lsect->section->contents)
6271 + elf_section_data (lsect->section)->rel_count));
6272 ++elf_section_data (lsect->section)->rel_count;
6277 relocation = (lsect->section->output_offset
6278 + linker_section_ptr->offset
6279 - lsect->hole_offset
6280 - lsect->sym_offset);
6282 #ifdef DEBUG
6283 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6284 lsect->name, (long)relocation, (long)relocation);
6285 #endif
6287 /* Subtract out the addend, because it will get added back in by the normal
6288 processing. */
6289 return relocation - linker_section_ptr->addend;
6292 /* Garbage collect unused sections. */
6294 static boolean elf_gc_mark
6295 PARAMS ((struct bfd_link_info *info, asection *sec,
6296 asection * (*gc_mark_hook)
6297 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6298 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6300 static boolean elf_gc_sweep
6301 PARAMS ((struct bfd_link_info *info,
6302 boolean (*gc_sweep_hook)
6303 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6304 const Elf_Internal_Rela *relocs))));
6306 static boolean elf_gc_sweep_symbol
6307 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6309 static boolean elf_gc_allocate_got_offsets
6310 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6312 static boolean elf_gc_propagate_vtable_entries_used
6313 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6315 static boolean elf_gc_smash_unused_vtentry_relocs
6316 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6318 /* The mark phase of garbage collection. For a given section, mark
6319 it, and all the sections which define symbols to which it refers. */
6321 static boolean
6322 elf_gc_mark (info, sec, gc_mark_hook)
6323 struct bfd_link_info *info;
6324 asection *sec;
6325 asection * (*gc_mark_hook)
6326 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6327 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6329 boolean ret = true;
6331 sec->gc_mark = 1;
6333 /* Look through the section relocs. */
6335 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6337 Elf_Internal_Rela *relstart, *rel, *relend;
6338 Elf_Internal_Shdr *symtab_hdr;
6339 struct elf_link_hash_entry **sym_hashes;
6340 size_t nlocsyms;
6341 size_t extsymoff;
6342 Elf_External_Sym *locsyms, *freesyms = NULL;
6343 bfd *input_bfd = sec->owner;
6344 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6346 /* GCFIXME: how to arrange so that relocs and symbols are not
6347 reread continually? */
6349 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6350 sym_hashes = elf_sym_hashes (input_bfd);
6352 /* Read the local symbols. */
6353 if (elf_bad_symtab (input_bfd))
6355 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6356 extsymoff = 0;
6358 else
6359 extsymoff = nlocsyms = symtab_hdr->sh_info;
6360 if (symtab_hdr->contents)
6361 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6362 else if (nlocsyms == 0)
6363 locsyms = NULL;
6364 else
6366 locsyms = freesyms =
6367 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6368 if (freesyms == NULL
6369 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6370 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6371 nlocsyms, input_bfd)
6372 != nlocsyms * sizeof (Elf_External_Sym)))
6374 ret = false;
6375 goto out1;
6379 /* Read the relocations. */
6380 relstart = (NAME(_bfd_elf,link_read_relocs)
6381 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6382 info->keep_memory));
6383 if (relstart == NULL)
6385 ret = false;
6386 goto out1;
6388 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6390 for (rel = relstart; rel < relend; rel++)
6392 unsigned long r_symndx;
6393 asection *rsec;
6394 struct elf_link_hash_entry *h;
6395 Elf_Internal_Sym s;
6397 r_symndx = ELF_R_SYM (rel->r_info);
6398 if (r_symndx == 0)
6399 continue;
6401 if (elf_bad_symtab (sec->owner))
6403 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6404 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6405 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6406 else
6408 h = sym_hashes[r_symndx - extsymoff];
6409 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6412 else if (r_symndx >= nlocsyms)
6414 h = sym_hashes[r_symndx - extsymoff];
6415 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6417 else
6419 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6420 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6423 if (rsec && !rsec->gc_mark)
6424 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6426 ret = false;
6427 goto out2;
6431 out2:
6432 if (!info->keep_memory)
6433 free (relstart);
6434 out1:
6435 if (freesyms)
6436 free (freesyms);
6439 return ret;
6442 /* The sweep phase of garbage collection. Remove all garbage sections. */
6444 static boolean
6445 elf_gc_sweep (info, gc_sweep_hook)
6446 struct bfd_link_info *info;
6447 boolean (*gc_sweep_hook)
6448 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6449 const Elf_Internal_Rela *relocs));
6451 bfd *sub;
6453 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6455 asection *o;
6457 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6458 continue;
6460 for (o = sub->sections; o != NULL; o = o->next)
6462 /* Keep special sections. Keep .debug sections. */
6463 if ((o->flags & SEC_LINKER_CREATED)
6464 || (o->flags & SEC_DEBUGGING))
6465 o->gc_mark = 1;
6467 if (o->gc_mark)
6468 continue;
6470 /* Skip sweeping sections already excluded. */
6471 if (o->flags & SEC_EXCLUDE)
6472 continue;
6474 /* Since this is early in the link process, it is simple
6475 to remove a section from the output. */
6476 o->flags |= SEC_EXCLUDE;
6478 /* But we also have to update some of the relocation
6479 info we collected before. */
6480 if (gc_sweep_hook
6481 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6483 Elf_Internal_Rela *internal_relocs;
6484 boolean r;
6486 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6487 (o->owner, o, NULL, NULL, info->keep_memory));
6488 if (internal_relocs == NULL)
6489 return false;
6491 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
6493 if (!info->keep_memory)
6494 free (internal_relocs);
6496 if (!r)
6497 return false;
6502 /* Remove the symbols that were in the swept sections from the dynamic
6503 symbol table. GCFIXME: Anyone know how to get them out of the
6504 static symbol table as well? */
6506 int i = 0;
6508 elf_link_hash_traverse (elf_hash_table (info),
6509 elf_gc_sweep_symbol,
6510 (PTR) &i);
6512 elf_hash_table (info)->dynsymcount = i;
6515 return true;
6518 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6520 static boolean
6521 elf_gc_sweep_symbol (h, idxptr)
6522 struct elf_link_hash_entry *h;
6523 PTR idxptr;
6525 int *idx = (int *) idxptr;
6527 if (h->dynindx != -1
6528 && ((h->root.type != bfd_link_hash_defined
6529 && h->root.type != bfd_link_hash_defweak)
6530 || h->root.u.def.section->gc_mark))
6531 h->dynindx = (*idx)++;
6533 return true;
6536 /* Propogate collected vtable information. This is called through
6537 elf_link_hash_traverse. */
6539 static boolean
6540 elf_gc_propagate_vtable_entries_used (h, okp)
6541 struct elf_link_hash_entry *h;
6542 PTR okp;
6544 /* Those that are not vtables. */
6545 if (h->vtable_parent == NULL)
6546 return true;
6548 /* Those vtables that do not have parents, we cannot merge. */
6549 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6550 return true;
6552 /* If we've already been done, exit. */
6553 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6554 return true;
6556 /* Make sure the parent's table is up to date. */
6557 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6559 if (h->vtable_entries_used == NULL)
6561 /* None of this table's entries were referenced. Re-use the
6562 parent's table. */
6563 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6564 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6566 else
6568 size_t n;
6569 boolean *cu, *pu;
6571 /* Or the parent's entries into ours. */
6572 cu = h->vtable_entries_used;
6573 cu[-1] = true;
6574 pu = h->vtable_parent->vtable_entries_used;
6575 if (pu != NULL)
6577 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6578 while (--n != 0)
6580 if (*pu) *cu = true;
6581 pu++, cu++;
6586 return true;
6589 static boolean
6590 elf_gc_smash_unused_vtentry_relocs (h, okp)
6591 struct elf_link_hash_entry *h;
6592 PTR okp;
6594 asection *sec;
6595 bfd_vma hstart, hend;
6596 Elf_Internal_Rela *relstart, *relend, *rel;
6597 struct elf_backend_data *bed;
6599 /* Take care of both those symbols that do not describe vtables as
6600 well as those that are not loaded. */
6601 if (h->vtable_parent == NULL)
6602 return true;
6604 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6605 || h->root.type == bfd_link_hash_defweak);
6607 sec = h->root.u.def.section;
6608 hstart = h->root.u.def.value;
6609 hend = hstart + h->size;
6611 relstart = (NAME(_bfd_elf,link_read_relocs)
6612 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6613 if (!relstart)
6614 return *(boolean *)okp = false;
6615 bed = get_elf_backend_data (sec->owner);
6616 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6618 for (rel = relstart; rel < relend; ++rel)
6619 if (rel->r_offset >= hstart && rel->r_offset < hend)
6621 /* If the entry is in use, do nothing. */
6622 if (h->vtable_entries_used
6623 && (rel->r_offset - hstart) < h->vtable_entries_size)
6625 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6626 if (h->vtable_entries_used[entry])
6627 continue;
6629 /* Otherwise, kill it. */
6630 rel->r_offset = rel->r_info = rel->r_addend = 0;
6633 return true;
6636 /* Do mark and sweep of unused sections. */
6638 boolean
6639 elf_gc_sections (abfd, info)
6640 bfd *abfd;
6641 struct bfd_link_info *info;
6643 boolean ok = true;
6644 bfd *sub;
6645 asection * (*gc_mark_hook)
6646 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6647 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6649 if (!get_elf_backend_data (abfd)->can_gc_sections
6650 || info->relocateable || info->emitrelocations
6651 || elf_hash_table (info)->dynamic_sections_created)
6652 return true;
6654 /* Apply transitive closure to the vtable entry usage info. */
6655 elf_link_hash_traverse (elf_hash_table (info),
6656 elf_gc_propagate_vtable_entries_used,
6657 (PTR) &ok);
6658 if (!ok)
6659 return false;
6661 /* Kill the vtable relocations that were not used. */
6662 elf_link_hash_traverse (elf_hash_table (info),
6663 elf_gc_smash_unused_vtentry_relocs,
6664 (PTR) &ok);
6665 if (!ok)
6666 return false;
6668 /* Grovel through relocs to find out who stays ... */
6670 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6671 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6673 asection *o;
6675 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6676 continue;
6678 for (o = sub->sections; o != NULL; o = o->next)
6680 if (o->flags & SEC_KEEP)
6681 if (!elf_gc_mark (info, o, gc_mark_hook))
6682 return false;
6686 /* ... and mark SEC_EXCLUDE for those that go. */
6687 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6688 return false;
6690 return true;
6693 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6695 boolean
6696 elf_gc_record_vtinherit (abfd, sec, h, offset)
6697 bfd *abfd;
6698 asection *sec;
6699 struct elf_link_hash_entry *h;
6700 bfd_vma offset;
6702 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6703 struct elf_link_hash_entry **search, *child;
6704 bfd_size_type extsymcount;
6706 /* The sh_info field of the symtab header tells us where the
6707 external symbols start. We don't care about the local symbols at
6708 this point. */
6709 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6710 if (!elf_bad_symtab (abfd))
6711 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6713 sym_hashes = elf_sym_hashes (abfd);
6714 sym_hashes_end = sym_hashes + extsymcount;
6716 /* Hunt down the child symbol, which is in this section at the same
6717 offset as the relocation. */
6718 for (search = sym_hashes; search != sym_hashes_end; ++search)
6720 if ((child = *search) != NULL
6721 && (child->root.type == bfd_link_hash_defined
6722 || child->root.type == bfd_link_hash_defweak)
6723 && child->root.u.def.section == sec
6724 && child->root.u.def.value == offset)
6725 goto win;
6728 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6729 bfd_get_filename (abfd), sec->name,
6730 (unsigned long)offset);
6731 bfd_set_error (bfd_error_invalid_operation);
6732 return false;
6734 win:
6735 if (!h)
6737 /* This *should* only be the absolute section. It could potentially
6738 be that someone has defined a non-global vtable though, which
6739 would be bad. It isn't worth paging in the local symbols to be
6740 sure though; that case should simply be handled by the assembler. */
6742 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6744 else
6745 child->vtable_parent = h;
6747 return true;
6750 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6752 boolean
6753 elf_gc_record_vtentry (abfd, sec, h, addend)
6754 bfd *abfd ATTRIBUTE_UNUSED;
6755 asection *sec ATTRIBUTE_UNUSED;
6756 struct elf_link_hash_entry *h;
6757 bfd_vma addend;
6759 if (addend >= h->vtable_entries_size)
6761 size_t size, bytes;
6762 boolean *ptr = h->vtable_entries_used;
6764 /* While the symbol is undefined, we have to be prepared to handle
6765 a zero size. */
6766 if (h->root.type == bfd_link_hash_undefined)
6767 size = addend;
6768 else
6770 size = h->size;
6771 if (size < addend)
6773 /* Oops! We've got a reference past the defined end of
6774 the table. This is probably a bug -- shall we warn? */
6775 size = addend;
6779 /* Allocate one extra entry for use as a "done" flag for the
6780 consolidation pass. */
6781 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6783 if (ptr)
6785 ptr = bfd_realloc (ptr - 1, bytes);
6787 if (ptr != NULL)
6789 size_t oldbytes;
6791 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6792 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6795 else
6796 ptr = bfd_zmalloc (bytes);
6798 if (ptr == NULL)
6799 return false;
6801 /* And arrange for that done flag to be at index -1. */
6802 h->vtable_entries_used = ptr + 1;
6803 h->vtable_entries_size = size;
6806 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6808 return true;
6811 /* And an accompanying bit to work out final got entry offsets once
6812 we're done. Should be called from final_link. */
6814 boolean
6815 elf_gc_common_finalize_got_offsets (abfd, info)
6816 bfd *abfd;
6817 struct bfd_link_info *info;
6819 bfd *i;
6820 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6821 bfd_vma gotoff;
6823 /* The GOT offset is relative to the .got section, but the GOT header is
6824 put into the .got.plt section, if the backend uses it. */
6825 if (bed->want_got_plt)
6826 gotoff = 0;
6827 else
6828 gotoff = bed->got_header_size;
6830 /* Do the local .got entries first. */
6831 for (i = info->input_bfds; i; i = i->link_next)
6833 bfd_signed_vma *local_got;
6834 bfd_size_type j, locsymcount;
6835 Elf_Internal_Shdr *symtab_hdr;
6837 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6838 continue;
6840 local_got = elf_local_got_refcounts (i);
6841 if (!local_got)
6842 continue;
6844 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6845 if (elf_bad_symtab (i))
6846 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6847 else
6848 locsymcount = symtab_hdr->sh_info;
6850 for (j = 0; j < locsymcount; ++j)
6852 if (local_got[j] > 0)
6854 local_got[j] = gotoff;
6855 gotoff += ARCH_SIZE / 8;
6857 else
6858 local_got[j] = (bfd_vma) -1;
6862 /* Then the global .got entries. .plt refcounts are handled by
6863 adjust_dynamic_symbol */
6864 elf_link_hash_traverse (elf_hash_table (info),
6865 elf_gc_allocate_got_offsets,
6866 (PTR) &gotoff);
6867 return true;
6870 /* We need a special top-level link routine to convert got reference counts
6871 to real got offsets. */
6873 static boolean
6874 elf_gc_allocate_got_offsets (h, offarg)
6875 struct elf_link_hash_entry *h;
6876 PTR offarg;
6878 bfd_vma *off = (bfd_vma *) offarg;
6880 if (h->got.refcount > 0)
6882 h->got.offset = off[0];
6883 off[0] += ARCH_SIZE / 8;
6885 else
6886 h->got.offset = (bfd_vma) -1;
6888 return true;
6891 /* Many folk need no more in the way of final link than this, once
6892 got entry reference counting is enabled. */
6894 boolean
6895 elf_gc_common_final_link (abfd, info)
6896 bfd *abfd;
6897 struct bfd_link_info *info;
6899 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6900 return false;
6902 /* Invoke the regular ELF backend linker to do all the work. */
6903 return elf_bfd_final_link (abfd, info);
6906 /* This function will be called though elf_link_hash_traverse to store
6907 all hash value of the exported symbols in an array. */
6909 static boolean
6910 elf_collect_hash_codes (h, data)
6911 struct elf_link_hash_entry *h;
6912 PTR data;
6914 unsigned long **valuep = (unsigned long **) data;
6915 const char *name;
6916 char *p;
6917 unsigned long ha;
6918 char *alc = NULL;
6920 /* Ignore indirect symbols. These are added by the versioning code. */
6921 if (h->dynindx == -1)
6922 return true;
6924 name = h->root.root.string;
6925 p = strchr (name, ELF_VER_CHR);
6926 if (p != NULL)
6928 alc = bfd_malloc (p - name + 1);
6929 memcpy (alc, name, p - name);
6930 alc[p - name] = '\0';
6931 name = alc;
6934 /* Compute the hash value. */
6935 ha = bfd_elf_hash (name);
6937 /* Store the found hash value in the array given as the argument. */
6938 *(*valuep)++ = ha;
6940 /* And store it in the struct so that we can put it in the hash table
6941 later. */
6942 h->elf_hash_value = ha;
6944 if (alc != NULL)
6945 free (alc);
6947 return true;