2001-01-03 Philip Blundell <pb@futuretv.com>
[binutils.git] / bfd / elflink.h
blobb3e1bbc6fc1e9969fb52878ec038e9af26966e00
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 symbol. */
84 static boolean
85 is_global_symbol_definition (abfd, sym)
86 bfd * abfd ATTRIBUTE_UNUSED;
87 Elf_Internal_Sym * sym;
89 /* Local symbols do not count, but target specific ones might. */
90 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
91 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
92 return false;
94 /* If the section is undefined, then so is the symbol. */
95 if (sym->st_shndx == SHN_UNDEF)
96 return false;
98 /* If the symbol is defined in the common section, then
99 it is a common definition and so does not count. */
100 if (sym->st_shndx == SHN_COMMON)
101 return false;
103 /* If the symbol is in a target specific section then we
104 must rely upon the backend to tell us what it is. */
105 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
106 /* FIXME - this function is not coded yet:
108 return _bfd_is_global_symbol_definition (abfd, sym);
110 Instead for now assume that the definition is not global,
111 Even if this is wrong, at least the linker will behave
112 in the same way that it used to do. */
113 return false;
115 return true;
119 /* Search the symbol table of the archive element of the archive ABFD
120 whoes archove map contains a mention of SYMDEF, and determine if
121 the symbol is defined in this element. */
122 static boolean
123 elf_link_is_defined_archive_symbol (abfd, symdef)
124 bfd * abfd;
125 carsym * symdef;
127 Elf_Internal_Shdr * hdr;
128 Elf_External_Sym * esym;
129 Elf_External_Sym * esymend;
130 Elf_External_Sym * buf = NULL;
131 size_t symcount;
132 size_t extsymcount;
133 size_t extsymoff;
134 boolean result = false;
136 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
137 if (abfd == (bfd *) NULL)
138 return false;
140 if (! bfd_check_format (abfd, bfd_object))
141 return false;
143 /* If we have already included the element containing this symbol in the
144 link then we do not need to include it again. Just claim that any symbol
145 it contains is not a definition, so that our caller will not decide to
146 (re)include this element. */
147 if (abfd->archive_pass)
148 return false;
150 /* Select the appropriate symbol table. */
151 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
152 hdr = &elf_tdata (abfd)->symtab_hdr;
153 else
154 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
156 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
158 /* The sh_info field of the symtab header tells us where the
159 external symbols start. We don't care about the local symbols. */
160 if (elf_bad_symtab (abfd))
162 extsymcount = symcount;
163 extsymoff = 0;
165 else
167 extsymcount = symcount - hdr->sh_info;
168 extsymoff = hdr->sh_info;
171 buf = ((Elf_External_Sym *)
172 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
173 if (buf == NULL && extsymcount != 0)
174 return false;
176 /* Read in the symbol table.
177 FIXME: This ought to be cached somewhere. */
178 if (bfd_seek (abfd,
179 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
180 SEEK_SET) != 0
181 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
182 != extsymcount * sizeof (Elf_External_Sym)))
184 free (buf);
185 return false;
188 /* Scan the symbol table looking for SYMDEF. */
189 esymend = buf + extsymcount;
190 for (esym = buf;
191 esym < esymend;
192 esym++)
194 Elf_Internal_Sym sym;
195 const char * name;
197 elf_swap_symbol_in (abfd, esym, & sym);
199 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
200 if (name == (const char *) NULL)
201 break;
203 if (strcmp (name, symdef->name) == 0)
205 result = is_global_symbol_definition (abfd, & sym);
206 break;
210 free (buf);
212 return result;
216 /* Add symbols from an ELF archive file to the linker hash table. We
217 don't use _bfd_generic_link_add_archive_symbols because of a
218 problem which arises on UnixWare. The UnixWare libc.so is an
219 archive which includes an entry libc.so.1 which defines a bunch of
220 symbols. The libc.so archive also includes a number of other
221 object files, which also define symbols, some of which are the same
222 as those defined in libc.so.1. Correct linking requires that we
223 consider each object file in turn, and include it if it defines any
224 symbols we need. _bfd_generic_link_add_archive_symbols does not do
225 this; it looks through the list of undefined symbols, and includes
226 any object file which defines them. When this algorithm is used on
227 UnixWare, it winds up pulling in libc.so.1 early and defining a
228 bunch of symbols. This means that some of the other objects in the
229 archive are not included in the link, which is incorrect since they
230 precede libc.so.1 in the archive.
232 Fortunately, ELF archive handling is simpler than that done by
233 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
234 oddities. In ELF, if we find a symbol in the archive map, and the
235 symbol is currently undefined, we know that we must pull in that
236 object file.
238 Unfortunately, we do have to make multiple passes over the symbol
239 table until nothing further is resolved. */
241 static boolean
242 elf_link_add_archive_symbols (abfd, info)
243 bfd *abfd;
244 struct bfd_link_info *info;
246 symindex c;
247 boolean *defined = NULL;
248 boolean *included = NULL;
249 carsym *symdefs;
250 boolean loop;
252 if (! bfd_has_map (abfd))
254 /* An empty archive is a special case. */
255 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
256 return true;
257 bfd_set_error (bfd_error_no_armap);
258 return false;
261 /* Keep track of all symbols we know to be already defined, and all
262 files we know to be already included. This is to speed up the
263 second and subsequent passes. */
264 c = bfd_ardata (abfd)->symdef_count;
265 if (c == 0)
266 return true;
267 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
268 included = (boolean *) bfd_malloc (c * sizeof (boolean));
269 if (defined == (boolean *) NULL || included == (boolean *) NULL)
270 goto error_return;
271 memset (defined, 0, c * sizeof (boolean));
272 memset (included, 0, c * sizeof (boolean));
274 symdefs = bfd_ardata (abfd)->symdefs;
278 file_ptr last;
279 symindex i;
280 carsym *symdef;
281 carsym *symdefend;
283 loop = false;
284 last = -1;
286 symdef = symdefs;
287 symdefend = symdef + c;
288 for (i = 0; symdef < symdefend; symdef++, i++)
290 struct elf_link_hash_entry *h;
291 bfd *element;
292 struct bfd_link_hash_entry *undefs_tail;
293 symindex mark;
295 if (defined[i] || included[i])
296 continue;
297 if (symdef->file_offset == last)
299 included[i] = true;
300 continue;
303 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
304 false, false, false);
306 if (h == NULL)
308 char *p, *copy;
310 /* If this is a default version (the name contains @@),
311 look up the symbol again without the version. The
312 effect is that references to the symbol without the
313 version will be matched by the default symbol in the
314 archive. */
316 p = strchr (symdef->name, ELF_VER_CHR);
317 if (p == NULL || p[1] != ELF_VER_CHR)
318 continue;
320 copy = bfd_alloc (abfd, p - symdef->name + 1);
321 if (copy == NULL)
322 goto error_return;
323 memcpy (copy, symdef->name, p - symdef->name);
324 copy[p - symdef->name] = '\0';
326 h = elf_link_hash_lookup (elf_hash_table (info), copy,
327 false, false, false);
329 bfd_release (abfd, copy);
332 if (h == NULL)
333 continue;
335 if (h->root.type == bfd_link_hash_common)
337 /* We currently have a common symbol. The archive map contains
338 a reference to this symbol, so we may want to include it. We
339 only want to include it however, if this archive element
340 contains a definition of the symbol, not just another common
341 declaration of it.
343 Unfortunately some archivers (including GNU ar) will put
344 declarations of common symbols into their archive maps, as
345 well as real definitions, so we cannot just go by the archive
346 map alone. Instead we must read in the element's symbol
347 table and check that to see what kind of symbol definition
348 this is. */
349 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
350 continue;
352 else if (h->root.type != bfd_link_hash_undefined)
354 if (h->root.type != bfd_link_hash_undefweak)
355 defined[i] = true;
356 continue;
359 /* We need to include this archive member. */
360 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
361 if (element == (bfd *) NULL)
362 goto error_return;
364 if (! bfd_check_format (element, bfd_object))
365 goto error_return;
367 /* Doublecheck that we have not included this object
368 already--it should be impossible, but there may be
369 something wrong with the archive. */
370 if (element->archive_pass != 0)
372 bfd_set_error (bfd_error_bad_value);
373 goto error_return;
375 element->archive_pass = 1;
377 undefs_tail = info->hash->undefs_tail;
379 if (! (*info->callbacks->add_archive_element) (info, element,
380 symdef->name))
381 goto error_return;
382 if (! elf_link_add_object_symbols (element, info))
383 goto error_return;
385 /* If there are any new undefined symbols, we need to make
386 another pass through the archive in order to see whether
387 they can be defined. FIXME: This isn't perfect, because
388 common symbols wind up on undefs_tail and because an
389 undefined symbol which is defined later on in this pass
390 does not require another pass. This isn't a bug, but it
391 does make the code less efficient than it could be. */
392 if (undefs_tail != info->hash->undefs_tail)
393 loop = true;
395 /* Look backward to mark all symbols from this object file
396 which we have already seen in this pass. */
397 mark = i;
400 included[mark] = true;
401 if (mark == 0)
402 break;
403 --mark;
405 while (symdefs[mark].file_offset == symdef->file_offset);
407 /* We mark subsequent symbols from this object file as we go
408 on through the loop. */
409 last = symdef->file_offset;
412 while (loop);
414 free (defined);
415 free (included);
417 return true;
419 error_return:
420 if (defined != (boolean *) NULL)
421 free (defined);
422 if (included != (boolean *) NULL)
423 free (included);
424 return false;
427 /* This function is called when we want to define a new symbol. It
428 handles the various cases which arise when we find a definition in
429 a dynamic object, or when there is already a definition in a
430 dynamic object. The new symbol is described by NAME, SYM, PSEC,
431 and PVALUE. We set SYM_HASH to the hash table entry. We set
432 OVERRIDE if the old symbol is overriding a new definition. We set
433 TYPE_CHANGE_OK if it is OK for the type to change. We set
434 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
435 change, we mean that we shouldn't warn if the type or size does
436 change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
437 a shared object. */
439 static boolean
440 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
441 override, type_change_ok, size_change_ok, dt_needed)
442 bfd *abfd;
443 struct bfd_link_info *info;
444 const char *name;
445 Elf_Internal_Sym *sym;
446 asection **psec;
447 bfd_vma *pvalue;
448 struct elf_link_hash_entry **sym_hash;
449 boolean *override;
450 boolean *type_change_ok;
451 boolean *size_change_ok;
452 boolean dt_needed;
454 asection *sec;
455 struct elf_link_hash_entry *h;
456 int bind;
457 bfd *oldbfd;
458 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
460 *override = false;
462 sec = *psec;
463 bind = ELF_ST_BIND (sym->st_info);
465 if (! bfd_is_und_section (sec))
466 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
467 else
468 h = ((struct elf_link_hash_entry *)
469 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
470 if (h == NULL)
471 return false;
472 *sym_hash = h;
474 /* This code is for coping with dynamic objects, and is only useful
475 if we are doing an ELF link. */
476 if (info->hash->creator != abfd->xvec)
477 return true;
479 /* For merging, we only care about real symbols. */
481 while (h->root.type == bfd_link_hash_indirect
482 || h->root.type == bfd_link_hash_warning)
483 h = (struct elf_link_hash_entry *) h->root.u.i.link;
485 /* If we just created the symbol, mark it as being an ELF symbol.
486 Other than that, there is nothing to do--there is no merge issue
487 with a newly defined symbol--so we just return. */
489 if (h->root.type == bfd_link_hash_new)
491 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
492 return true;
495 /* OLDBFD is a BFD associated with the existing symbol. */
497 switch (h->root.type)
499 default:
500 oldbfd = NULL;
501 break;
503 case bfd_link_hash_undefined:
504 case bfd_link_hash_undefweak:
505 oldbfd = h->root.u.undef.abfd;
506 break;
508 case bfd_link_hash_defined:
509 case bfd_link_hash_defweak:
510 oldbfd = h->root.u.def.section->owner;
511 break;
513 case bfd_link_hash_common:
514 oldbfd = h->root.u.c.p->section->owner;
515 break;
518 /* In cases involving weak versioned symbols, we may wind up trying
519 to merge a symbol with itself. Catch that here, to avoid the
520 confusion that results if we try to override a symbol with
521 itself. The additional tests catch cases like
522 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
523 dynamic object, which we do want to handle here. */
524 if (abfd == oldbfd
525 && ((abfd->flags & DYNAMIC) == 0
526 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
527 return true;
529 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
530 respectively, is from a dynamic object. */
532 if ((abfd->flags & DYNAMIC) != 0)
533 newdyn = true;
534 else
535 newdyn = false;
537 if (oldbfd != NULL)
538 olddyn = (oldbfd->flags & DYNAMIC) != 0;
539 else
541 asection *hsec;
543 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
544 indices used by MIPS ELF. */
545 switch (h->root.type)
547 default:
548 hsec = NULL;
549 break;
551 case bfd_link_hash_defined:
552 case bfd_link_hash_defweak:
553 hsec = h->root.u.def.section;
554 break;
556 case bfd_link_hash_common:
557 hsec = h->root.u.c.p->section;
558 break;
561 if (hsec == NULL)
562 olddyn = false;
563 else
564 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
567 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
568 respectively, appear to be a definition rather than reference. */
570 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
571 newdef = false;
572 else
573 newdef = true;
575 if (h->root.type == bfd_link_hash_undefined
576 || h->root.type == bfd_link_hash_undefweak
577 || h->root.type == bfd_link_hash_common)
578 olddef = false;
579 else
580 olddef = true;
582 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
583 symbol, respectively, appears to be a common symbol in a dynamic
584 object. If a symbol appears in an uninitialized section, and is
585 not weak, and is not a function, then it may be a common symbol
586 which was resolved when the dynamic object was created. We want
587 to treat such symbols specially, because they raise special
588 considerations when setting the symbol size: if the symbol
589 appears as a common symbol in a regular object, and the size in
590 the regular object is larger, we must make sure that we use the
591 larger size. This problematic case can always be avoided in C,
592 but it must be handled correctly when using Fortran shared
593 libraries.
595 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
596 likewise for OLDDYNCOMMON and OLDDEF.
598 Note that this test is just a heuristic, and that it is quite
599 possible to have an uninitialized symbol in a shared object which
600 is really a definition, rather than a common symbol. This could
601 lead to some minor confusion when the symbol really is a common
602 symbol in some regular object. However, I think it will be
603 harmless. */
605 if (newdyn
606 && newdef
607 && (sec->flags & SEC_ALLOC) != 0
608 && (sec->flags & SEC_LOAD) == 0
609 && sym->st_size > 0
610 && bind != STB_WEAK
611 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
612 newdyncommon = true;
613 else
614 newdyncommon = false;
616 if (olddyn
617 && olddef
618 && h->root.type == bfd_link_hash_defined
619 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
620 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
621 && (h->root.u.def.section->flags & SEC_LOAD) == 0
622 && h->size > 0
623 && h->type != STT_FUNC)
624 olddyncommon = true;
625 else
626 olddyncommon = false;
628 /* It's OK to change the type if either the existing symbol or the
629 new symbol is weak unless it comes from a DT_NEEDED entry of
630 a shared object, in which case, the DT_NEEDED entry may not be
631 required at the run time. */
633 if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
634 || h->root.type == bfd_link_hash_undefweak
635 || bind == STB_WEAK)
636 *type_change_ok = true;
638 /* It's OK to change the size if either the existing symbol or the
639 new symbol is weak, or if the old symbol is undefined. */
641 if (*type_change_ok
642 || h->root.type == bfd_link_hash_undefined)
643 *size_change_ok = true;
645 /* If both the old and the new symbols look like common symbols in a
646 dynamic object, set the size of the symbol to the larger of the
647 two. */
649 if (olddyncommon
650 && newdyncommon
651 && sym->st_size != h->size)
653 /* Since we think we have two common symbols, issue a multiple
654 common warning if desired. Note that we only warn if the
655 size is different. If the size is the same, we simply let
656 the old symbol override the new one as normally happens with
657 symbols defined in dynamic objects. */
659 if (! ((*info->callbacks->multiple_common)
660 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
661 h->size, abfd, bfd_link_hash_common, sym->st_size)))
662 return false;
664 if (sym->st_size > h->size)
665 h->size = sym->st_size;
667 *size_change_ok = true;
670 /* If we are looking at a dynamic object, and we have found a
671 definition, we need to see if the symbol was already defined by
672 some other object. If so, we want to use the existing
673 definition, and we do not want to report a multiple symbol
674 definition error; we do this by clobbering *PSEC to be
675 bfd_und_section_ptr.
677 We treat a common symbol as a definition if the symbol in the
678 shared library is a function, since common symbols always
679 represent variables; this can cause confusion in principle, but
680 any such confusion would seem to indicate an erroneous program or
681 shared library. We also permit a common symbol in a regular
682 object to override a weak symbol in a shared object.
684 We prefer a non-weak definition in a shared library to a weak
685 definition in the executable unless it comes from a DT_NEEDED
686 entry of a shared object, in which case, the DT_NEEDED entry
687 may not be required at the run time. */
689 if (newdyn
690 && newdef
691 && (olddef
692 || (h->root.type == bfd_link_hash_common
693 && (bind == STB_WEAK
694 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
695 && (h->root.type != bfd_link_hash_defweak
696 || dt_needed
697 || bind == STB_WEAK))
699 *override = true;
700 newdef = false;
701 newdyncommon = false;
703 *psec = sec = bfd_und_section_ptr;
704 *size_change_ok = true;
706 /* If we get here when the old symbol is a common symbol, then
707 we are explicitly letting it override a weak symbol or
708 function in a dynamic object, and we don't want to warn about
709 a type change. If the old symbol is a defined symbol, a type
710 change warning may still be appropriate. */
712 if (h->root.type == bfd_link_hash_common)
713 *type_change_ok = true;
716 /* Handle the special case of an old common symbol merging with a
717 new symbol which looks like a common symbol in a shared object.
718 We change *PSEC and *PVALUE to make the new symbol look like a
719 common symbol, and let _bfd_generic_link_add_one_symbol will do
720 the right thing. */
722 if (newdyncommon
723 && h->root.type == bfd_link_hash_common)
725 *override = true;
726 newdef = false;
727 newdyncommon = false;
728 *pvalue = sym->st_size;
729 *psec = sec = bfd_com_section_ptr;
730 *size_change_ok = true;
733 /* If the old symbol is from a dynamic object, and the new symbol is
734 a definition which is not from a dynamic object, then the new
735 symbol overrides the old symbol. Symbols from regular files
736 always take precedence over symbols from dynamic objects, even if
737 they are defined after the dynamic object in the link.
739 As above, we again permit a common symbol in a regular object to
740 override a definition in a shared object if the shared object
741 symbol is a function or is weak.
743 As above, we permit a non-weak definition in a shared object to
744 override a weak definition in a regular object. */
746 if (! newdyn
747 && (newdef
748 || (bfd_is_com_section (sec)
749 && (h->root.type == bfd_link_hash_defweak
750 || h->type == STT_FUNC)))
751 && olddyn
752 && olddef
753 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
754 && (bind != STB_WEAK
755 || h->root.type == bfd_link_hash_defweak))
757 /* Change the hash table entry to undefined, and let
758 _bfd_generic_link_add_one_symbol do the right thing with the
759 new definition. */
761 h->root.type = bfd_link_hash_undefined;
762 h->root.u.undef.abfd = h->root.u.def.section->owner;
763 *size_change_ok = true;
765 olddef = false;
766 olddyncommon = false;
768 /* We again permit a type change when a common symbol may be
769 overriding a function. */
771 if (bfd_is_com_section (sec))
772 *type_change_ok = true;
774 /* This union may have been set to be non-NULL when this symbol
775 was seen in a dynamic object. We must force the union to be
776 NULL, so that it is correct for a regular symbol. */
778 h->verinfo.vertree = NULL;
780 /* In this special case, if H is the target of an indirection,
781 we want the caller to frob with H rather than with the
782 indirect symbol. That will permit the caller to redefine the
783 target of the indirection, rather than the indirect symbol
784 itself. FIXME: This will break the -y option if we store a
785 symbol with a different name. */
786 *sym_hash = h;
789 /* Handle the special case of a new common symbol merging with an
790 old symbol that looks like it might be a common symbol defined in
791 a shared object. Note that we have already handled the case in
792 which a new common symbol should simply override the definition
793 in the shared library. */
795 if (! newdyn
796 && bfd_is_com_section (sec)
797 && olddyncommon)
799 /* It would be best if we could set the hash table entry to a
800 common symbol, but we don't know what to use for the section
801 or the alignment. */
802 if (! ((*info->callbacks->multiple_common)
803 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
804 h->size, abfd, bfd_link_hash_common, sym->st_size)))
805 return false;
807 /* If the predumed common symbol in the dynamic object is
808 larger, pretend that the new symbol has its size. */
810 if (h->size > *pvalue)
811 *pvalue = h->size;
813 /* FIXME: We no longer know the alignment required by the symbol
814 in the dynamic object, so we just wind up using the one from
815 the regular object. */
817 olddef = false;
818 olddyncommon = false;
820 h->root.type = bfd_link_hash_undefined;
821 h->root.u.undef.abfd = h->root.u.def.section->owner;
823 *size_change_ok = true;
824 *type_change_ok = true;
826 h->verinfo.vertree = NULL;
829 /* Handle the special case of a weak definition in a regular object
830 followed by a non-weak definition in a shared object. In this
831 case, we prefer the definition in the shared object unless it
832 comes from a DT_NEEDED entry of a shared object, in which case,
833 the DT_NEEDED entry may not be required at the run time. */
834 if (olddef
835 && ! dt_needed
836 && h->root.type == bfd_link_hash_defweak
837 && newdef
838 && newdyn
839 && bind != STB_WEAK)
841 /* To make this work we have to frob the flags so that the rest
842 of the code does not think we are using the regular
843 definition. */
844 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
845 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
846 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
847 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
848 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
849 | ELF_LINK_HASH_DEF_DYNAMIC);
851 /* If H is the target of an indirection, we want the caller to
852 use H rather than the indirect symbol. Otherwise if we are
853 defining a new indirect symbol we will wind up attaching it
854 to the entry we are overriding. */
855 *sym_hash = h;
858 /* Handle the special case of a non-weak definition in a shared
859 object followed by a weak definition in a regular object. In
860 this case we prefer to definition in the shared object. To make
861 this work we have to tell the caller to not treat the new symbol
862 as a definition. */
863 if (olddef
864 && olddyn
865 && h->root.type != bfd_link_hash_defweak
866 && newdef
867 && ! newdyn
868 && bind == STB_WEAK)
869 *override = true;
871 return true;
874 /* Add symbols from an ELF object file to the linker hash table. */
876 static boolean
877 elf_link_add_object_symbols (abfd, info)
878 bfd *abfd;
879 struct bfd_link_info *info;
881 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
882 const Elf_Internal_Sym *,
883 const char **, flagword *,
884 asection **, bfd_vma *));
885 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
886 asection *, const Elf_Internal_Rela *));
887 boolean collect;
888 Elf_Internal_Shdr *hdr;
889 size_t symcount;
890 size_t extsymcount;
891 size_t extsymoff;
892 Elf_External_Sym *buf = NULL;
893 struct elf_link_hash_entry **sym_hash;
894 boolean dynamic;
895 bfd_byte *dynver = NULL;
896 Elf_External_Versym *extversym = NULL;
897 Elf_External_Versym *ever;
898 Elf_External_Dyn *dynbuf = NULL;
899 struct elf_link_hash_entry *weaks;
900 Elf_External_Sym *esym;
901 Elf_External_Sym *esymend;
902 struct elf_backend_data *bed;
903 boolean dt_needed;
905 bed = get_elf_backend_data (abfd);
906 add_symbol_hook = bed->elf_add_symbol_hook;
907 collect = bed->collect;
909 if ((abfd->flags & DYNAMIC) == 0)
910 dynamic = false;
911 else
913 dynamic = true;
915 /* You can't use -r against a dynamic object. Also, there's no
916 hope of using a dynamic object which does not exactly match
917 the format of the output file. */
918 if (info->relocateable || info->hash->creator != abfd->xvec)
920 bfd_set_error (bfd_error_invalid_operation);
921 goto error_return;
925 /* As a GNU extension, any input sections which are named
926 .gnu.warning.SYMBOL are treated as warning symbols for the given
927 symbol. This differs from .gnu.warning sections, which generate
928 warnings when they are included in an output file. */
929 if (! info->shared)
931 asection *s;
933 for (s = abfd->sections; s != NULL; s = s->next)
935 const char *name;
937 name = bfd_get_section_name (abfd, s);
938 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
940 char *msg;
941 bfd_size_type sz;
943 name += sizeof ".gnu.warning." - 1;
945 /* If this is a shared object, then look up the symbol
946 in the hash table. If it is there, and it is already
947 been defined, then we will not be using the entry
948 from this shared object, so we don't need to warn.
949 FIXME: If we see the definition in a regular object
950 later on, we will warn, but we shouldn't. The only
951 fix is to keep track of what warnings we are supposed
952 to emit, and then handle them all at the end of the
953 link. */
954 if (dynamic && abfd->xvec == info->hash->creator)
956 struct elf_link_hash_entry *h;
958 h = elf_link_hash_lookup (elf_hash_table (info), name,
959 false, false, true);
961 /* FIXME: What about bfd_link_hash_common? */
962 if (h != NULL
963 && (h->root.type == bfd_link_hash_defined
964 || h->root.type == bfd_link_hash_defweak))
966 /* We don't want to issue this warning. Clobber
967 the section size so that the warning does not
968 get copied into the output file. */
969 s->_raw_size = 0;
970 continue;
974 sz = bfd_section_size (abfd, s);
975 msg = (char *) bfd_alloc (abfd, sz + 1);
976 if (msg == NULL)
977 goto error_return;
979 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
980 goto error_return;
982 msg[sz] = '\0';
984 if (! (_bfd_generic_link_add_one_symbol
985 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
986 false, collect, (struct bfd_link_hash_entry **) NULL)))
987 goto error_return;
989 if (! info->relocateable)
991 /* Clobber the section size so that the warning does
992 not get copied into the output file. */
993 s->_raw_size = 0;
999 /* If this is a dynamic object, we always link against the .dynsym
1000 symbol table, not the .symtab symbol table. The dynamic linker
1001 will only see the .dynsym symbol table, so there is no reason to
1002 look at .symtab for a dynamic object. */
1004 if (! dynamic || elf_dynsymtab (abfd) == 0)
1005 hdr = &elf_tdata (abfd)->symtab_hdr;
1006 else
1007 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1009 if (dynamic)
1011 /* Read in any version definitions. */
1013 if (! _bfd_elf_slurp_version_tables (abfd))
1014 goto error_return;
1016 /* Read in the symbol versions, but don't bother to convert them
1017 to internal format. */
1018 if (elf_dynversym (abfd) != 0)
1020 Elf_Internal_Shdr *versymhdr;
1022 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1023 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1024 if (extversym == NULL)
1025 goto error_return;
1026 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1027 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1028 != versymhdr->sh_size))
1029 goto error_return;
1033 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1035 /* The sh_info field of the symtab header tells us where the
1036 external symbols start. We don't care about the local symbols at
1037 this point. */
1038 if (elf_bad_symtab (abfd))
1040 extsymcount = symcount;
1041 extsymoff = 0;
1043 else
1045 extsymcount = symcount - hdr->sh_info;
1046 extsymoff = hdr->sh_info;
1049 buf = ((Elf_External_Sym *)
1050 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1051 if (buf == NULL && extsymcount != 0)
1052 goto error_return;
1054 /* We store a pointer to the hash table entry for each external
1055 symbol. */
1056 sym_hash = ((struct elf_link_hash_entry **)
1057 bfd_alloc (abfd,
1058 extsymcount * sizeof (struct elf_link_hash_entry *)));
1059 if (sym_hash == NULL)
1060 goto error_return;
1061 elf_sym_hashes (abfd) = sym_hash;
1063 dt_needed = false;
1065 if (! dynamic)
1067 /* If we are creating a shared library, create all the dynamic
1068 sections immediately. We need to attach them to something,
1069 so we attach them to this BFD, provided it is the right
1070 format. FIXME: If there are no input BFD's of the same
1071 format as the output, we can't make a shared library. */
1072 if (info->shared
1073 && ! elf_hash_table (info)->dynamic_sections_created
1074 && abfd->xvec == info->hash->creator)
1076 if (! elf_link_create_dynamic_sections (abfd, info))
1077 goto error_return;
1080 else
1082 asection *s;
1083 boolean add_needed;
1084 const char *name;
1085 bfd_size_type oldsize;
1086 bfd_size_type strindex;
1088 /* Find the name to use in a DT_NEEDED entry that refers to this
1089 object. If the object has a DT_SONAME entry, we use it.
1090 Otherwise, if the generic linker stuck something in
1091 elf_dt_name, we use that. Otherwise, we just use the file
1092 name. If the generic linker put a null string into
1093 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1094 there is a DT_SONAME entry. */
1095 add_needed = true;
1096 name = bfd_get_filename (abfd);
1097 if (elf_dt_name (abfd) != NULL)
1099 name = elf_dt_name (abfd);
1100 if (*name == '\0')
1102 if (elf_dt_soname (abfd) != NULL)
1103 dt_needed = true;
1105 add_needed = false;
1108 s = bfd_get_section_by_name (abfd, ".dynamic");
1109 if (s != NULL)
1111 Elf_External_Dyn *extdyn;
1112 Elf_External_Dyn *extdynend;
1113 int elfsec;
1114 unsigned long link;
1115 int rpath;
1116 int runpath;
1118 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1119 if (dynbuf == NULL)
1120 goto error_return;
1122 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1123 (file_ptr) 0, s->_raw_size))
1124 goto error_return;
1126 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1127 if (elfsec == -1)
1128 goto error_return;
1129 link = elf_elfsections (abfd)[elfsec]->sh_link;
1132 /* The shared libraries distributed with hpux11 have a bogus
1133 sh_link field for the ".dynamic" section. This code detects
1134 when LINK refers to a section that is not a string table and
1135 tries to find the string table for the ".dynsym" section
1136 instead. */
1137 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1138 if (hdr->sh_type != SHT_STRTAB)
1140 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1141 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1142 if (elfsec == -1)
1143 goto error_return;
1144 link = elf_elfsections (abfd)[elfsec]->sh_link;
1148 extdyn = dynbuf;
1149 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1150 rpath = 0;
1151 runpath = 0;
1152 for (; extdyn < extdynend; extdyn++)
1154 Elf_Internal_Dyn dyn;
1156 elf_swap_dyn_in (abfd, extdyn, &dyn);
1157 if (dyn.d_tag == DT_SONAME)
1159 name = bfd_elf_string_from_elf_section (abfd, link,
1160 dyn.d_un.d_val);
1161 if (name == NULL)
1162 goto error_return;
1164 if (dyn.d_tag == DT_NEEDED)
1166 struct bfd_link_needed_list *n, **pn;
1167 char *fnm, *anm;
1169 n = ((struct bfd_link_needed_list *)
1170 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1171 fnm = bfd_elf_string_from_elf_section (abfd, link,
1172 dyn.d_un.d_val);
1173 if (n == NULL || fnm == NULL)
1174 goto error_return;
1175 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1176 if (anm == NULL)
1177 goto error_return;
1178 strcpy (anm, fnm);
1179 n->name = anm;
1180 n->by = abfd;
1181 n->next = NULL;
1182 for (pn = &elf_hash_table (info)->needed;
1183 *pn != NULL;
1184 pn = &(*pn)->next)
1186 *pn = n;
1188 if (dyn.d_tag == DT_RUNPATH)
1190 struct bfd_link_needed_list *n, **pn;
1191 char *fnm, *anm;
1193 /* When we see DT_RPATH before DT_RUNPATH, we have
1194 to clear runpath. Do _NOT_ bfd_release, as that
1195 frees all more recently bfd_alloc'd blocks as
1196 well. */
1197 if (rpath && elf_hash_table (info)->runpath)
1198 elf_hash_table (info)->runpath = NULL;
1200 n = ((struct bfd_link_needed_list *)
1201 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1202 fnm = bfd_elf_string_from_elf_section (abfd, link,
1203 dyn.d_un.d_val);
1204 if (n == NULL || fnm == NULL)
1205 goto error_return;
1206 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1207 if (anm == NULL)
1208 goto error_return;
1209 strcpy (anm, fnm);
1210 n->name = anm;
1211 n->by = abfd;
1212 n->next = NULL;
1213 for (pn = &elf_hash_table (info)->runpath;
1214 *pn != NULL;
1215 pn = &(*pn)->next)
1217 *pn = n;
1218 runpath = 1;
1219 rpath = 0;
1221 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
1222 if (!runpath && dyn.d_tag == DT_RPATH)
1224 struct bfd_link_needed_list *n, **pn;
1225 char *fnm, *anm;
1227 n = ((struct bfd_link_needed_list *)
1228 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1229 fnm = bfd_elf_string_from_elf_section (abfd, link,
1230 dyn.d_un.d_val);
1231 if (n == NULL || fnm == NULL)
1232 goto error_return;
1233 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1234 if (anm == NULL)
1235 goto error_return;
1236 strcpy (anm, fnm);
1237 n->name = anm;
1238 n->by = abfd;
1239 n->next = NULL;
1240 for (pn = &elf_hash_table (info)->runpath;
1241 *pn != NULL;
1242 pn = &(*pn)->next)
1244 *pn = n;
1245 rpath = 1;
1249 free (dynbuf);
1250 dynbuf = NULL;
1253 /* We do not want to include any of the sections in a dynamic
1254 object in the output file. We hack by simply clobbering the
1255 list of sections in the BFD. This could be handled more
1256 cleanly by, say, a new section flag; the existing
1257 SEC_NEVER_LOAD flag is not the one we want, because that one
1258 still implies that the section takes up space in the output
1259 file. */
1260 abfd->sections = NULL;
1261 abfd->section_count = 0;
1263 /* If this is the first dynamic object found in the link, create
1264 the special sections required for dynamic linking. */
1265 if (! elf_hash_table (info)->dynamic_sections_created)
1267 if (! elf_link_create_dynamic_sections (abfd, info))
1268 goto error_return;
1271 if (add_needed)
1273 /* Add a DT_NEEDED entry for this dynamic object. */
1274 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1275 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1276 true, false);
1277 if (strindex == (bfd_size_type) -1)
1278 goto error_return;
1280 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1282 asection *sdyn;
1283 Elf_External_Dyn *dyncon, *dynconend;
1285 /* The hash table size did not change, which means that
1286 the dynamic object name was already entered. If we
1287 have already included this dynamic object in the
1288 link, just ignore it. There is no reason to include
1289 a particular dynamic object more than once. */
1290 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1291 ".dynamic");
1292 BFD_ASSERT (sdyn != NULL);
1294 dyncon = (Elf_External_Dyn *) sdyn->contents;
1295 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1296 sdyn->_raw_size);
1297 for (; dyncon < dynconend; dyncon++)
1299 Elf_Internal_Dyn dyn;
1301 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1302 &dyn);
1303 if (dyn.d_tag == DT_NEEDED
1304 && dyn.d_un.d_val == strindex)
1306 if (buf != NULL)
1307 free (buf);
1308 if (extversym != NULL)
1309 free (extversym);
1310 return true;
1315 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1316 goto error_return;
1319 /* Save the SONAME, if there is one, because sometimes the
1320 linker emulation code will need to know it. */
1321 if (*name == '\0')
1322 name = bfd_get_filename (abfd);
1323 elf_dt_name (abfd) = name;
1326 if (bfd_seek (abfd,
1327 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1328 SEEK_SET) != 0
1329 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1330 != extsymcount * sizeof (Elf_External_Sym)))
1331 goto error_return;
1333 weaks = NULL;
1335 ever = extversym != NULL ? extversym + extsymoff : NULL;
1336 esymend = buf + extsymcount;
1337 for (esym = buf;
1338 esym < esymend;
1339 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1341 Elf_Internal_Sym sym;
1342 int bind;
1343 bfd_vma value;
1344 asection *sec;
1345 flagword flags;
1346 const char *name;
1347 struct elf_link_hash_entry *h;
1348 boolean definition;
1349 boolean size_change_ok, type_change_ok;
1350 boolean new_weakdef;
1351 unsigned int old_alignment;
1353 elf_swap_symbol_in (abfd, esym, &sym);
1355 flags = BSF_NO_FLAGS;
1356 sec = NULL;
1357 value = sym.st_value;
1358 *sym_hash = NULL;
1360 bind = ELF_ST_BIND (sym.st_info);
1361 if (bind == STB_LOCAL)
1363 /* This should be impossible, since ELF requires that all
1364 global symbols follow all local symbols, and that sh_info
1365 point to the first global symbol. Unfortunatealy, Irix 5
1366 screws this up. */
1367 continue;
1369 else if (bind == STB_GLOBAL)
1371 if (sym.st_shndx != SHN_UNDEF
1372 && sym.st_shndx != SHN_COMMON)
1373 flags = BSF_GLOBAL;
1375 else if (bind == STB_WEAK)
1376 flags = BSF_WEAK;
1377 else
1379 /* Leave it up to the processor backend. */
1382 if (sym.st_shndx == SHN_UNDEF)
1383 sec = bfd_und_section_ptr;
1384 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1386 sec = section_from_elf_index (abfd, sym.st_shndx);
1387 if (sec == NULL)
1388 sec = bfd_abs_section_ptr;
1389 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1390 value -= sec->vma;
1392 else if (sym.st_shndx == SHN_ABS)
1393 sec = bfd_abs_section_ptr;
1394 else if (sym.st_shndx == SHN_COMMON)
1396 sec = bfd_com_section_ptr;
1397 /* What ELF calls the size we call the value. What ELF
1398 calls the value we call the alignment. */
1399 value = sym.st_size;
1401 else
1403 /* Leave it up to the processor backend. */
1406 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1407 if (name == (const char *) NULL)
1408 goto error_return;
1410 if (add_symbol_hook)
1412 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1413 &value))
1414 goto error_return;
1416 /* The hook function sets the name to NULL if this symbol
1417 should be skipped for some reason. */
1418 if (name == (const char *) NULL)
1419 continue;
1422 /* Sanity check that all possibilities were handled. */
1423 if (sec == (asection *) NULL)
1425 bfd_set_error (bfd_error_bad_value);
1426 goto error_return;
1429 if (bfd_is_und_section (sec)
1430 || bfd_is_com_section (sec))
1431 definition = false;
1432 else
1433 definition = true;
1435 size_change_ok = false;
1436 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1437 old_alignment = 0;
1438 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1440 Elf_Internal_Versym iver;
1441 unsigned int vernum = 0;
1442 boolean override;
1444 if (ever != NULL)
1446 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1447 vernum = iver.vs_vers & VERSYM_VERSION;
1449 /* If this is a hidden symbol, or if it is not version
1450 1, we append the version name to the symbol name.
1451 However, we do not modify a non-hidden absolute
1452 symbol, because it might be the version symbol
1453 itself. FIXME: What if it isn't? */
1454 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1455 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1457 const char *verstr;
1458 int namelen, newlen;
1459 char *newname, *p;
1461 if (sym.st_shndx != SHN_UNDEF)
1463 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1465 (*_bfd_error_handler)
1466 (_("%s: %s: invalid version %u (max %d)"),
1467 bfd_get_filename (abfd), name, vernum,
1468 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1469 bfd_set_error (bfd_error_bad_value);
1470 goto error_return;
1472 else if (vernum > 1)
1473 verstr =
1474 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1475 else
1476 verstr = "";
1478 else
1480 /* We cannot simply test for the number of
1481 entries in the VERNEED section since the
1482 numbers for the needed versions do not start
1483 at 0. */
1484 Elf_Internal_Verneed *t;
1486 verstr = NULL;
1487 for (t = elf_tdata (abfd)->verref;
1488 t != NULL;
1489 t = t->vn_nextref)
1491 Elf_Internal_Vernaux *a;
1493 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1495 if (a->vna_other == vernum)
1497 verstr = a->vna_nodename;
1498 break;
1501 if (a != NULL)
1502 break;
1504 if (verstr == NULL)
1506 (*_bfd_error_handler)
1507 (_("%s: %s: invalid needed version %d"),
1508 bfd_get_filename (abfd), name, vernum);
1509 bfd_set_error (bfd_error_bad_value);
1510 goto error_return;
1514 namelen = strlen (name);
1515 newlen = namelen + strlen (verstr) + 2;
1516 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1517 ++newlen;
1519 newname = (char *) bfd_alloc (abfd, newlen);
1520 if (newname == NULL)
1521 goto error_return;
1522 strcpy (newname, name);
1523 p = newname + namelen;
1524 *p++ = ELF_VER_CHR;
1525 /* If this is a defined non-hidden version symbol,
1526 we add another @ to the name. This indicates the
1527 default version of the symbol. */
1528 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1529 && sym.st_shndx != SHN_UNDEF)
1530 *p++ = ELF_VER_CHR;
1531 strcpy (p, verstr);
1533 name = newname;
1537 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1538 sym_hash, &override, &type_change_ok,
1539 &size_change_ok, dt_needed))
1540 goto error_return;
1542 if (override)
1543 definition = false;
1545 h = *sym_hash;
1546 while (h->root.type == bfd_link_hash_indirect
1547 || h->root.type == bfd_link_hash_warning)
1548 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1550 /* Remember the old alignment if this is a common symbol, so
1551 that we don't reduce the alignment later on. We can't
1552 check later, because _bfd_generic_link_add_one_symbol
1553 will set a default for the alignment which we want to
1554 override. */
1555 if (h->root.type == bfd_link_hash_common)
1556 old_alignment = h->root.u.c.p->alignment_power;
1558 if (elf_tdata (abfd)->verdef != NULL
1559 && ! override
1560 && vernum > 1
1561 && definition)
1562 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1565 if (! (_bfd_generic_link_add_one_symbol
1566 (info, abfd, name, flags, sec, value, (const char *) NULL,
1567 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1568 goto error_return;
1570 h = *sym_hash;
1571 while (h->root.type == bfd_link_hash_indirect
1572 || h->root.type == bfd_link_hash_warning)
1573 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1574 *sym_hash = h;
1576 new_weakdef = false;
1577 if (dynamic
1578 && definition
1579 && (flags & BSF_WEAK) != 0
1580 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1581 && info->hash->creator->flavour == bfd_target_elf_flavour
1582 && h->weakdef == NULL)
1584 /* Keep a list of all weak defined non function symbols from
1585 a dynamic object, using the weakdef field. Later in this
1586 function we will set the weakdef field to the correct
1587 value. We only put non-function symbols from dynamic
1588 objects on this list, because that happens to be the only
1589 time we need to know the normal symbol corresponding to a
1590 weak symbol, and the information is time consuming to
1591 figure out. If the weakdef field is not already NULL,
1592 then this symbol was already defined by some previous
1593 dynamic object, and we will be using that previous
1594 definition anyhow. */
1596 h->weakdef = weaks;
1597 weaks = h;
1598 new_weakdef = true;
1601 /* Set the alignment of a common symbol. */
1602 if (sym.st_shndx == SHN_COMMON
1603 && h->root.type == bfd_link_hash_common)
1605 unsigned int align;
1607 align = bfd_log2 (sym.st_value);
1608 if (align > old_alignment
1609 /* Permit an alignment power of zero if an alignment of one
1610 is specified and no other alignments have been specified. */
1611 || (sym.st_value == 1 && old_alignment == 0))
1612 h->root.u.c.p->alignment_power = align;
1615 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1617 int old_flags;
1618 boolean dynsym;
1619 int new_flag;
1621 /* Remember the symbol size and type. */
1622 if (sym.st_size != 0
1623 && (definition || h->size == 0))
1625 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1626 (*_bfd_error_handler)
1627 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1628 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1629 bfd_get_filename (abfd));
1631 h->size = sym.st_size;
1634 /* If this is a common symbol, then we always want H->SIZE
1635 to be the size of the common symbol. The code just above
1636 won't fix the size if a common symbol becomes larger. We
1637 don't warn about a size change here, because that is
1638 covered by --warn-common. */
1639 if (h->root.type == bfd_link_hash_common)
1640 h->size = h->root.u.c.size;
1642 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1643 && (definition || h->type == STT_NOTYPE))
1645 if (h->type != STT_NOTYPE
1646 && h->type != ELF_ST_TYPE (sym.st_info)
1647 && ! type_change_ok)
1648 (*_bfd_error_handler)
1649 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1650 name, h->type, ELF_ST_TYPE (sym.st_info),
1651 bfd_get_filename (abfd));
1653 h->type = ELF_ST_TYPE (sym.st_info);
1656 /* If st_other has a processor-specific meaning, specific code
1657 might be needed here. */
1658 if (sym.st_other != 0)
1660 /* Combine visibilities, using the most constraining one. */
1661 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1662 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1664 if (symvis && (hvis > symvis || hvis == 0))
1665 h->other = sym.st_other;
1667 /* If neither has visibility, use the st_other of the
1668 definition. This is an arbitrary choice, since the
1669 other bits have no general meaning. */
1670 if (!symvis && !hvis
1671 && (definition || h->other == 0))
1672 h->other = sym.st_other;
1675 /* Set a flag in the hash table entry indicating the type of
1676 reference or definition we just found. Keep a count of
1677 the number of dynamic symbols we find. A dynamic symbol
1678 is one which is referenced or defined by both a regular
1679 object and a shared object. */
1680 old_flags = h->elf_link_hash_flags;
1681 dynsym = false;
1682 if (! dynamic)
1684 if (! definition)
1686 new_flag = ELF_LINK_HASH_REF_REGULAR;
1687 if (bind != STB_WEAK)
1688 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1690 else
1691 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1692 if (info->shared
1693 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1694 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1695 dynsym = true;
1697 else
1699 if (! definition)
1700 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1701 else
1702 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1703 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1704 | ELF_LINK_HASH_REF_REGULAR)) != 0
1705 || (h->weakdef != NULL
1706 && ! new_weakdef
1707 && h->weakdef->dynindx != -1))
1708 dynsym = true;
1711 h->elf_link_hash_flags |= new_flag;
1713 /* If this symbol has a version, and it is the default
1714 version, we create an indirect symbol from the default
1715 name to the fully decorated name. This will cause
1716 external references which do not specify a version to be
1717 bound to this version of the symbol. */
1718 if (definition || h->root.type == bfd_link_hash_common)
1720 char *p;
1722 p = strchr (name, ELF_VER_CHR);
1723 if (p != NULL && p[1] == ELF_VER_CHR)
1725 char *shortname;
1726 struct elf_link_hash_entry *hi;
1727 boolean override;
1729 shortname = bfd_hash_allocate (&info->hash->table,
1730 p - name + 1);
1731 if (shortname == NULL)
1732 goto error_return;
1733 strncpy (shortname, name, p - name);
1734 shortname[p - name] = '\0';
1736 /* We are going to create a new symbol. Merge it
1737 with any existing symbol with this name. For the
1738 purposes of the merge, act as though we were
1739 defining the symbol we just defined, although we
1740 actually going to define an indirect symbol. */
1741 type_change_ok = false;
1742 size_change_ok = false;
1743 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1744 &value, &hi, &override,
1745 &type_change_ok,
1746 &size_change_ok, dt_needed))
1747 goto error_return;
1749 if (! override)
1751 if (! (_bfd_generic_link_add_one_symbol
1752 (info, abfd, shortname, BSF_INDIRECT,
1753 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1754 collect, (struct bfd_link_hash_entry **) &hi)))
1755 goto error_return;
1757 else
1759 /* In this case the symbol named SHORTNAME is
1760 overriding the indirect symbol we want to
1761 add. We were planning on making SHORTNAME an
1762 indirect symbol referring to NAME. SHORTNAME
1763 is the name without a version. NAME is the
1764 fully versioned name, and it is the default
1765 version.
1767 Overriding means that we already saw a
1768 definition for the symbol SHORTNAME in a
1769 regular object, and it is overriding the
1770 symbol defined in the dynamic object.
1772 When this happens, we actually want to change
1773 NAME, the symbol we just added, to refer to
1774 SHORTNAME. This will cause references to
1775 NAME in the shared object to become
1776 references to SHORTNAME in the regular
1777 object. This is what we expect when we
1778 override a function in a shared object: that
1779 the references in the shared object will be
1780 mapped to the definition in the regular
1781 object. */
1783 while (hi->root.type == bfd_link_hash_indirect
1784 || hi->root.type == bfd_link_hash_warning)
1785 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1787 h->root.type = bfd_link_hash_indirect;
1788 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1789 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1791 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1792 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1793 if (hi->elf_link_hash_flags
1794 & (ELF_LINK_HASH_REF_REGULAR
1795 | ELF_LINK_HASH_DEF_REGULAR))
1797 if (! _bfd_elf_link_record_dynamic_symbol (info,
1798 hi))
1799 goto error_return;
1803 /* Now set HI to H, so that the following code
1804 will set the other fields correctly. */
1805 hi = h;
1808 /* If there is a duplicate definition somewhere,
1809 then HI may not point to an indirect symbol. We
1810 will have reported an error to the user in that
1811 case. */
1813 if (hi->root.type == bfd_link_hash_indirect)
1815 struct elf_link_hash_entry *ht;
1817 /* If the symbol became indirect, then we assume
1818 that we have not seen a definition before. */
1819 BFD_ASSERT ((hi->elf_link_hash_flags
1820 & (ELF_LINK_HASH_DEF_DYNAMIC
1821 | ELF_LINK_HASH_DEF_REGULAR))
1822 == 0);
1824 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1825 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1827 /* See if the new flags lead us to realize that
1828 the symbol must be dynamic. */
1829 if (! dynsym)
1831 if (! dynamic)
1833 if (info->shared
1834 || ((hi->elf_link_hash_flags
1835 & ELF_LINK_HASH_REF_DYNAMIC)
1836 != 0))
1837 dynsym = true;
1839 else
1841 if ((hi->elf_link_hash_flags
1842 & ELF_LINK_HASH_REF_REGULAR) != 0)
1843 dynsym = true;
1848 /* We also need to define an indirection from the
1849 nondefault version of the symbol. */
1851 shortname = bfd_hash_allocate (&info->hash->table,
1852 strlen (name));
1853 if (shortname == NULL)
1854 goto error_return;
1855 strncpy (shortname, name, p - name);
1856 strcpy (shortname + (p - name), p + 1);
1858 /* Once again, merge with any existing symbol. */
1859 type_change_ok = false;
1860 size_change_ok = false;
1861 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1862 &value, &hi, &override,
1863 &type_change_ok,
1864 &size_change_ok, dt_needed))
1865 goto error_return;
1867 if (override)
1869 /* Here SHORTNAME is a versioned name, so we
1870 don't expect to see the type of override we
1871 do in the case above. */
1872 (*_bfd_error_handler)
1873 (_("%s: warning: unexpected redefinition of `%s'"),
1874 bfd_get_filename (abfd), shortname);
1876 else
1878 if (! (_bfd_generic_link_add_one_symbol
1879 (info, abfd, shortname, BSF_INDIRECT,
1880 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1881 collect, (struct bfd_link_hash_entry **) &hi)))
1882 goto error_return;
1884 /* If there is a duplicate definition somewhere,
1885 then HI may not point to an indirect symbol.
1886 We will have reported an error to the user in
1887 that case. */
1889 if (hi->root.type == bfd_link_hash_indirect)
1891 /* If the symbol became indirect, then we
1892 assume that we have not seen a definition
1893 before. */
1894 BFD_ASSERT ((hi->elf_link_hash_flags
1895 & (ELF_LINK_HASH_DEF_DYNAMIC
1896 | ELF_LINK_HASH_DEF_REGULAR))
1897 == 0);
1899 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1901 /* See if the new flags lead us to realize
1902 that the symbol must be dynamic. */
1903 if (! dynsym)
1905 if (! dynamic)
1907 if (info->shared
1908 || ((hi->elf_link_hash_flags
1909 & ELF_LINK_HASH_REF_DYNAMIC)
1910 != 0))
1911 dynsym = true;
1913 else
1915 if ((hi->elf_link_hash_flags
1916 & ELF_LINK_HASH_REF_REGULAR) != 0)
1917 dynsym = true;
1925 if (dynsym && h->dynindx == -1)
1927 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1928 goto error_return;
1929 if (h->weakdef != NULL
1930 && ! new_weakdef
1931 && h->weakdef->dynindx == -1)
1933 if (! _bfd_elf_link_record_dynamic_symbol (info,
1934 h->weakdef))
1935 goto error_return;
1938 else if (dynsym && h->dynindx != -1)
1939 /* If the symbol already has a dynamic index, but
1940 visibility says it should not be visible, turn it into
1941 a local symbol. */
1942 switch (ELF_ST_VISIBILITY (h->other))
1944 case STV_INTERNAL:
1945 case STV_HIDDEN:
1946 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1947 (*bed->elf_backend_hide_symbol) (info, h);
1948 break;
1951 if (dt_needed && definition
1952 && (h->elf_link_hash_flags
1953 & ELF_LINK_HASH_REF_REGULAR) != 0)
1955 bfd_size_type oldsize;
1956 bfd_size_type strindex;
1958 /* The symbol from a DT_NEEDED object is referenced from
1959 the regular object to create a dynamic executable. We
1960 have to make sure there is a DT_NEEDED entry for it. */
1962 dt_needed = false;
1963 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1964 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
1965 elf_dt_soname (abfd),
1966 true, false);
1967 if (strindex == (bfd_size_type) -1)
1968 goto error_return;
1970 if (oldsize
1971 == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1973 asection *sdyn;
1974 Elf_External_Dyn *dyncon, *dynconend;
1976 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1977 ".dynamic");
1978 BFD_ASSERT (sdyn != NULL);
1980 dyncon = (Elf_External_Dyn *) sdyn->contents;
1981 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1982 sdyn->_raw_size);
1983 for (; dyncon < dynconend; dyncon++)
1985 Elf_Internal_Dyn dyn;
1987 elf_swap_dyn_in (elf_hash_table (info)->dynobj,
1988 dyncon, &dyn);
1989 BFD_ASSERT (dyn.d_tag != DT_NEEDED ||
1990 dyn.d_un.d_val != strindex);
1994 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1995 goto error_return;
2000 /* Now set the weakdefs field correctly for all the weak defined
2001 symbols we found. The only way to do this is to search all the
2002 symbols. Since we only need the information for non functions in
2003 dynamic objects, that's the only time we actually put anything on
2004 the list WEAKS. We need this information so that if a regular
2005 object refers to a symbol defined weakly in a dynamic object, the
2006 real symbol in the dynamic object is also put in the dynamic
2007 symbols; we also must arrange for both symbols to point to the
2008 same memory location. We could handle the general case of symbol
2009 aliasing, but a general symbol alias can only be generated in
2010 assembler code, handling it correctly would be very time
2011 consuming, and other ELF linkers don't handle general aliasing
2012 either. */
2013 while (weaks != NULL)
2015 struct elf_link_hash_entry *hlook;
2016 asection *slook;
2017 bfd_vma vlook;
2018 struct elf_link_hash_entry **hpp;
2019 struct elf_link_hash_entry **hppend;
2021 hlook = weaks;
2022 weaks = hlook->weakdef;
2023 hlook->weakdef = NULL;
2025 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
2026 || hlook->root.type == bfd_link_hash_defweak
2027 || hlook->root.type == bfd_link_hash_common
2028 || hlook->root.type == bfd_link_hash_indirect);
2029 slook = hlook->root.u.def.section;
2030 vlook = hlook->root.u.def.value;
2032 hpp = elf_sym_hashes (abfd);
2033 hppend = hpp + extsymcount;
2034 for (; hpp < hppend; hpp++)
2036 struct elf_link_hash_entry *h;
2038 h = *hpp;
2039 if (h != NULL && h != hlook
2040 && h->root.type == bfd_link_hash_defined
2041 && h->root.u.def.section == slook
2042 && h->root.u.def.value == vlook)
2044 hlook->weakdef = h;
2046 /* If the weak definition is in the list of dynamic
2047 symbols, make sure the real definition is put there
2048 as well. */
2049 if (hlook->dynindx != -1
2050 && h->dynindx == -1)
2052 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2053 goto error_return;
2056 /* If the real definition is in the list of dynamic
2057 symbols, make sure the weak definition is put there
2058 as well. If we don't do this, then the dynamic
2059 loader might not merge the entries for the real
2060 definition and the weak definition. */
2061 if (h->dynindx != -1
2062 && hlook->dynindx == -1)
2064 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
2065 goto error_return;
2068 break;
2073 if (buf != NULL)
2075 free (buf);
2076 buf = NULL;
2079 if (extversym != NULL)
2081 free (extversym);
2082 extversym = NULL;
2085 /* If this object is the same format as the output object, and it is
2086 not a shared library, then let the backend look through the
2087 relocs.
2089 This is required to build global offset table entries and to
2090 arrange for dynamic relocs. It is not required for the
2091 particular common case of linking non PIC code, even when linking
2092 against shared libraries, but unfortunately there is no way of
2093 knowing whether an object file has been compiled PIC or not.
2094 Looking through the relocs is not particularly time consuming.
2095 The problem is that we must either (1) keep the relocs in memory,
2096 which causes the linker to require additional runtime memory or
2097 (2) read the relocs twice from the input file, which wastes time.
2098 This would be a good case for using mmap.
2100 I have no idea how to handle linking PIC code into a file of a
2101 different format. It probably can't be done. */
2102 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2103 if (! dynamic
2104 && abfd->xvec == info->hash->creator
2105 && check_relocs != NULL)
2107 asection *o;
2109 for (o = abfd->sections; o != NULL; o = o->next)
2111 Elf_Internal_Rela *internal_relocs;
2112 boolean ok;
2114 if ((o->flags & SEC_RELOC) == 0
2115 || o->reloc_count == 0
2116 || ((info->strip == strip_all || info->strip == strip_debugger)
2117 && (o->flags & SEC_DEBUGGING) != 0)
2118 || bfd_is_abs_section (o->output_section))
2119 continue;
2121 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2122 (abfd, o, (PTR) NULL,
2123 (Elf_Internal_Rela *) NULL,
2124 info->keep_memory));
2125 if (internal_relocs == NULL)
2126 goto error_return;
2128 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2130 if (! info->keep_memory)
2131 free (internal_relocs);
2133 if (! ok)
2134 goto error_return;
2138 /* If this is a non-traditional, non-relocateable link, try to
2139 optimize the handling of the .stab/.stabstr sections. */
2140 if (! dynamic
2141 && ! info->relocateable
2142 && ! info->traditional_format
2143 && info->hash->creator->flavour == bfd_target_elf_flavour
2144 && (info->strip != strip_all && info->strip != strip_debugger))
2146 asection *stab, *stabstr;
2148 stab = bfd_get_section_by_name (abfd, ".stab");
2149 if (stab != NULL)
2151 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2153 if (stabstr != NULL)
2155 struct bfd_elf_section_data *secdata;
2157 secdata = elf_section_data (stab);
2158 if (! _bfd_link_section_stabs (abfd,
2159 &elf_hash_table (info)->stab_info,
2160 stab, stabstr,
2161 &secdata->stab_info))
2162 goto error_return;
2167 return true;
2169 error_return:
2170 if (buf != NULL)
2171 free (buf);
2172 if (dynbuf != NULL)
2173 free (dynbuf);
2174 if (dynver != NULL)
2175 free (dynver);
2176 if (extversym != NULL)
2177 free (extversym);
2178 return false;
2181 /* Create some sections which will be filled in with dynamic linking
2182 information. ABFD is an input file which requires dynamic sections
2183 to be created. The dynamic sections take up virtual memory space
2184 when the final executable is run, so we need to create them before
2185 addresses are assigned to the output sections. We work out the
2186 actual contents and size of these sections later. */
2188 boolean
2189 elf_link_create_dynamic_sections (abfd, info)
2190 bfd *abfd;
2191 struct bfd_link_info *info;
2193 flagword flags;
2194 register asection *s;
2195 struct elf_link_hash_entry *h;
2196 struct elf_backend_data *bed;
2198 if (elf_hash_table (info)->dynamic_sections_created)
2199 return true;
2201 /* Make sure that all dynamic sections use the same input BFD. */
2202 if (elf_hash_table (info)->dynobj == NULL)
2203 elf_hash_table (info)->dynobj = abfd;
2204 else
2205 abfd = elf_hash_table (info)->dynobj;
2207 /* Note that we set the SEC_IN_MEMORY flag for all of these
2208 sections. */
2209 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2210 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2212 /* A dynamically linked executable has a .interp section, but a
2213 shared library does not. */
2214 if (! info->shared)
2216 s = bfd_make_section (abfd, ".interp");
2217 if (s == NULL
2218 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2219 return false;
2222 /* Create sections to hold version informations. These are removed
2223 if they are not needed. */
2224 s = bfd_make_section (abfd, ".gnu.version_d");
2225 if (s == NULL
2226 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2227 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2228 return false;
2230 s = bfd_make_section (abfd, ".gnu.version");
2231 if (s == NULL
2232 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2233 || ! bfd_set_section_alignment (abfd, s, 1))
2234 return false;
2236 s = bfd_make_section (abfd, ".gnu.version_r");
2237 if (s == NULL
2238 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2239 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2240 return false;
2242 s = bfd_make_section (abfd, ".dynsym");
2243 if (s == NULL
2244 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2245 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2246 return false;
2248 s = bfd_make_section (abfd, ".dynstr");
2249 if (s == NULL
2250 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2251 return false;
2253 /* Create a strtab to hold the dynamic symbol names. */
2254 if (elf_hash_table (info)->dynstr == NULL)
2256 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2257 if (elf_hash_table (info)->dynstr == NULL)
2258 return false;
2261 s = bfd_make_section (abfd, ".dynamic");
2262 if (s == NULL
2263 || ! bfd_set_section_flags (abfd, s, flags)
2264 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2265 return false;
2267 /* The special symbol _DYNAMIC is always set to the start of the
2268 .dynamic section. This call occurs before we have processed the
2269 symbols for any dynamic object, so we don't have to worry about
2270 overriding a dynamic definition. We could set _DYNAMIC in a
2271 linker script, but we only want to define it if we are, in fact,
2272 creating a .dynamic section. We don't want to define it if there
2273 is no .dynamic section, since on some ELF platforms the start up
2274 code examines it to decide how to initialize the process. */
2275 h = NULL;
2276 if (! (_bfd_generic_link_add_one_symbol
2277 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2278 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2279 (struct bfd_link_hash_entry **) &h)))
2280 return false;
2281 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2282 h->type = STT_OBJECT;
2284 if (info->shared
2285 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2286 return false;
2288 bed = get_elf_backend_data (abfd);
2290 s = bfd_make_section (abfd, ".hash");
2291 if (s == NULL
2292 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2293 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2294 return false;
2295 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2297 /* Let the backend create the rest of the sections. This lets the
2298 backend set the right flags. The backend will normally create
2299 the .got and .plt sections. */
2300 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2301 return false;
2303 elf_hash_table (info)->dynamic_sections_created = true;
2305 return true;
2308 /* Add an entry to the .dynamic table. */
2310 boolean
2311 elf_add_dynamic_entry (info, tag, val)
2312 struct bfd_link_info *info;
2313 bfd_vma tag;
2314 bfd_vma val;
2316 Elf_Internal_Dyn dyn;
2317 bfd *dynobj;
2318 asection *s;
2319 size_t newsize;
2320 bfd_byte *newcontents;
2322 dynobj = elf_hash_table (info)->dynobj;
2324 s = bfd_get_section_by_name (dynobj, ".dynamic");
2325 BFD_ASSERT (s != NULL);
2327 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2328 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2329 if (newcontents == NULL)
2330 return false;
2332 dyn.d_tag = tag;
2333 dyn.d_un.d_val = val;
2334 elf_swap_dyn_out (dynobj, &dyn,
2335 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2337 s->_raw_size = newsize;
2338 s->contents = newcontents;
2340 return true;
2343 /* Record a new local dynamic symbol. */
2345 boolean
2346 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2347 struct bfd_link_info *info;
2348 bfd *input_bfd;
2349 long input_indx;
2351 struct elf_link_local_dynamic_entry *entry;
2352 struct elf_link_hash_table *eht;
2353 struct bfd_strtab_hash *dynstr;
2354 Elf_External_Sym esym;
2355 unsigned long dynstr_index;
2356 char *name;
2358 /* See if the entry exists already. */
2359 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2360 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2361 return true;
2363 entry = (struct elf_link_local_dynamic_entry *)
2364 bfd_alloc (input_bfd, sizeof (*entry));
2365 if (entry == NULL)
2366 return false;
2368 /* Go find the symbol, so that we can find it's name. */
2369 if (bfd_seek (input_bfd,
2370 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2371 + input_indx * sizeof (Elf_External_Sym)),
2372 SEEK_SET) != 0
2373 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2374 != sizeof (Elf_External_Sym)))
2375 return false;
2376 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2378 name = (bfd_elf_string_from_elf_section
2379 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2380 entry->isym.st_name));
2382 dynstr = elf_hash_table (info)->dynstr;
2383 if (dynstr == NULL)
2385 /* Create a strtab to hold the dynamic symbol names. */
2386 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2387 if (dynstr == NULL)
2388 return false;
2391 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2392 if (dynstr_index == (unsigned long) -1)
2393 return false;
2394 entry->isym.st_name = dynstr_index;
2396 eht = elf_hash_table (info);
2398 entry->next = eht->dynlocal;
2399 eht->dynlocal = entry;
2400 entry->input_bfd = input_bfd;
2401 entry->input_indx = input_indx;
2402 eht->dynsymcount++;
2404 /* Whatever binding the symbol had before, it's now local. */
2405 entry->isym.st_info
2406 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2408 /* The dynindx will be set at the end of size_dynamic_sections. */
2410 return true;
2414 /* Read and swap the relocs from the section indicated by SHDR. This
2415 may be either a REL or a RELA section. The relocations are
2416 translated into RELA relocations and stored in INTERNAL_RELOCS,
2417 which should have already been allocated to contain enough space.
2418 The EXTERNAL_RELOCS are a buffer where the external form of the
2419 relocations should be stored.
2421 Returns false if something goes wrong. */
2423 static boolean
2424 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2425 internal_relocs)
2426 bfd *abfd;
2427 Elf_Internal_Shdr *shdr;
2428 PTR external_relocs;
2429 Elf_Internal_Rela *internal_relocs;
2431 struct elf_backend_data *bed;
2433 /* If there aren't any relocations, that's OK. */
2434 if (!shdr)
2435 return true;
2437 /* Position ourselves at the start of the section. */
2438 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2439 return false;
2441 /* Read the relocations. */
2442 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2443 != shdr->sh_size)
2444 return false;
2446 bed = get_elf_backend_data (abfd);
2448 /* Convert the external relocations to the internal format. */
2449 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2451 Elf_External_Rel *erel;
2452 Elf_External_Rel *erelend;
2453 Elf_Internal_Rela *irela;
2454 Elf_Internal_Rel *irel;
2456 erel = (Elf_External_Rel *) external_relocs;
2457 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2458 irela = internal_relocs;
2459 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2460 * sizeof (Elf_Internal_Rel)));
2461 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2463 unsigned char i;
2465 if (bed->s->swap_reloc_in)
2466 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2467 else
2468 elf_swap_reloc_in (abfd, erel, irel);
2470 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2472 irela[i].r_offset = irel[i].r_offset;
2473 irela[i].r_info = irel[i].r_info;
2474 irela[i].r_addend = 0;
2478 else
2480 Elf_External_Rela *erela;
2481 Elf_External_Rela *erelaend;
2482 Elf_Internal_Rela *irela;
2484 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2486 erela = (Elf_External_Rela *) external_relocs;
2487 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2488 irela = internal_relocs;
2489 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2491 if (bed->s->swap_reloca_in)
2492 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2493 else
2494 elf_swap_reloca_in (abfd, erela, irela);
2498 return true;
2501 /* Read and swap the relocs for a section O. They may have been
2502 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2503 not NULL, they are used as buffers to read into. They are known to
2504 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2505 the return value is allocated using either malloc or bfd_alloc,
2506 according to the KEEP_MEMORY argument. If O has two relocation
2507 sections (both REL and RELA relocations), then the REL_HDR
2508 relocations will appear first in INTERNAL_RELOCS, followed by the
2509 REL_HDR2 relocations. */
2511 Elf_Internal_Rela *
2512 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2513 keep_memory)
2514 bfd *abfd;
2515 asection *o;
2516 PTR external_relocs;
2517 Elf_Internal_Rela *internal_relocs;
2518 boolean keep_memory;
2520 Elf_Internal_Shdr *rel_hdr;
2521 PTR alloc1 = NULL;
2522 Elf_Internal_Rela *alloc2 = NULL;
2523 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2525 if (elf_section_data (o)->relocs != NULL)
2526 return elf_section_data (o)->relocs;
2528 if (o->reloc_count == 0)
2529 return NULL;
2531 rel_hdr = &elf_section_data (o)->rel_hdr;
2533 if (internal_relocs == NULL)
2535 size_t size;
2537 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2538 * sizeof (Elf_Internal_Rela));
2539 if (keep_memory)
2540 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2541 else
2542 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2543 if (internal_relocs == NULL)
2544 goto error_return;
2547 if (external_relocs == NULL)
2549 size_t size = (size_t) rel_hdr->sh_size;
2551 if (elf_section_data (o)->rel_hdr2)
2552 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2553 alloc1 = (PTR) bfd_malloc (size);
2554 if (alloc1 == NULL)
2555 goto error_return;
2556 external_relocs = alloc1;
2559 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2560 external_relocs,
2561 internal_relocs))
2562 goto error_return;
2563 if (!elf_link_read_relocs_from_section
2564 (abfd,
2565 elf_section_data (o)->rel_hdr2,
2566 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2567 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2568 * bed->s->int_rels_per_ext_rel)))
2569 goto error_return;
2571 /* Cache the results for next time, if we can. */
2572 if (keep_memory)
2573 elf_section_data (o)->relocs = internal_relocs;
2575 if (alloc1 != NULL)
2576 free (alloc1);
2578 /* Don't free alloc2, since if it was allocated we are passing it
2579 back (under the name of internal_relocs). */
2581 return internal_relocs;
2583 error_return:
2584 if (alloc1 != NULL)
2585 free (alloc1);
2586 if (alloc2 != NULL)
2587 free (alloc2);
2588 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;
6059 /* Allocate a pointer to live in a linker created section. */
6061 boolean
6062 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6063 bfd *abfd;
6064 struct bfd_link_info *info;
6065 elf_linker_section_t *lsect;
6066 struct elf_link_hash_entry *h;
6067 const Elf_Internal_Rela *rel;
6069 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6070 elf_linker_section_pointers_t *linker_section_ptr;
6071 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6073 BFD_ASSERT (lsect != NULL);
6075 /* Is this a global symbol? */
6076 if (h != NULL)
6078 /* Has this symbol already been allocated, if so, our work is done */
6079 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6080 rel->r_addend,
6081 lsect->which))
6082 return true;
6084 ptr_linker_section_ptr = &h->linker_section_pointer;
6085 /* Make sure this symbol is output as a dynamic symbol. */
6086 if (h->dynindx == -1)
6088 if (! elf_link_record_dynamic_symbol (info, h))
6089 return false;
6092 if (lsect->rel_section)
6093 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6096 else /* Allocation of a pointer to a local symbol */
6098 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6100 /* Allocate a table to hold the local symbols if first time */
6101 if (!ptr)
6103 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6104 register unsigned int i;
6106 ptr = (elf_linker_section_pointers_t **)
6107 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6109 if (!ptr)
6110 return false;
6112 elf_local_ptr_offsets (abfd) = ptr;
6113 for (i = 0; i < num_symbols; i++)
6114 ptr[i] = (elf_linker_section_pointers_t *)0;
6117 /* Has this symbol already been allocated, if so, our work is done */
6118 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6119 rel->r_addend,
6120 lsect->which))
6121 return true;
6123 ptr_linker_section_ptr = &ptr[r_symndx];
6125 if (info->shared)
6127 /* If we are generating a shared object, we need to
6128 output a R_<xxx>_RELATIVE reloc so that the
6129 dynamic linker can adjust this GOT entry. */
6130 BFD_ASSERT (lsect->rel_section != NULL);
6131 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6135 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6136 from internal memory. */
6137 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6138 linker_section_ptr = (elf_linker_section_pointers_t *)
6139 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6141 if (!linker_section_ptr)
6142 return false;
6144 linker_section_ptr->next = *ptr_linker_section_ptr;
6145 linker_section_ptr->addend = rel->r_addend;
6146 linker_section_ptr->which = lsect->which;
6147 linker_section_ptr->written_address_p = false;
6148 *ptr_linker_section_ptr = linker_section_ptr;
6150 #if 0
6151 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6153 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6154 lsect->hole_offset += ARCH_SIZE / 8;
6155 lsect->sym_offset += ARCH_SIZE / 8;
6156 if (lsect->sym_hash) /* Bump up symbol value if needed */
6158 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6159 #ifdef DEBUG
6160 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6161 lsect->sym_hash->root.root.string,
6162 (long)ARCH_SIZE / 8,
6163 (long)lsect->sym_hash->root.u.def.value);
6164 #endif
6167 else
6168 #endif
6169 linker_section_ptr->offset = lsect->section->_raw_size;
6171 lsect->section->_raw_size += ARCH_SIZE / 8;
6173 #ifdef DEBUG
6174 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6175 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6176 #endif
6178 return true;
6182 #if ARCH_SIZE==64
6183 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6184 #endif
6185 #if ARCH_SIZE==32
6186 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6187 #endif
6189 /* Fill in the address for a pointer generated in alinker section. */
6191 bfd_vma
6192 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6193 bfd *output_bfd;
6194 bfd *input_bfd;
6195 struct bfd_link_info *info;
6196 elf_linker_section_t *lsect;
6197 struct elf_link_hash_entry *h;
6198 bfd_vma relocation;
6199 const Elf_Internal_Rela *rel;
6200 int relative_reloc;
6202 elf_linker_section_pointers_t *linker_section_ptr;
6204 BFD_ASSERT (lsect != NULL);
6206 if (h != NULL) /* global symbol */
6208 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6209 rel->r_addend,
6210 lsect->which);
6212 BFD_ASSERT (linker_section_ptr != NULL);
6214 if (! elf_hash_table (info)->dynamic_sections_created
6215 || (info->shared
6216 && info->symbolic
6217 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6219 /* This is actually a static link, or it is a
6220 -Bsymbolic link and the symbol is defined
6221 locally. We must initialize this entry in the
6222 global section.
6224 When doing a dynamic link, we create a .rela.<xxx>
6225 relocation entry to initialize the value. This
6226 is done in the finish_dynamic_symbol routine. */
6227 if (!linker_section_ptr->written_address_p)
6229 linker_section_ptr->written_address_p = true;
6230 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6231 lsect->section->contents + linker_section_ptr->offset);
6235 else /* local symbol */
6237 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6238 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6239 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6240 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6241 rel->r_addend,
6242 lsect->which);
6244 BFD_ASSERT (linker_section_ptr != NULL);
6246 /* Write out pointer if it hasn't been rewritten out before */
6247 if (!linker_section_ptr->written_address_p)
6249 linker_section_ptr->written_address_p = true;
6250 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6251 lsect->section->contents + linker_section_ptr->offset);
6253 if (info->shared)
6255 asection *srel = lsect->rel_section;
6256 Elf_Internal_Rela outrel;
6258 /* We need to generate a relative reloc for the dynamic linker. */
6259 if (!srel)
6260 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6261 lsect->rel_name);
6263 BFD_ASSERT (srel != NULL);
6265 outrel.r_offset = (lsect->section->output_section->vma
6266 + lsect->section->output_offset
6267 + linker_section_ptr->offset);
6268 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6269 outrel.r_addend = 0;
6270 elf_swap_reloca_out (output_bfd, &outrel,
6271 (((Elf_External_Rela *)
6272 lsect->section->contents)
6273 + elf_section_data (lsect->section)->rel_count));
6274 ++elf_section_data (lsect->section)->rel_count;
6279 relocation = (lsect->section->output_offset
6280 + linker_section_ptr->offset
6281 - lsect->hole_offset
6282 - lsect->sym_offset);
6284 #ifdef DEBUG
6285 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6286 lsect->name, (long)relocation, (long)relocation);
6287 #endif
6289 /* Subtract out the addend, because it will get added back in by the normal
6290 processing. */
6291 return relocation - linker_section_ptr->addend;
6294 /* Garbage collect unused sections. */
6296 static boolean elf_gc_mark
6297 PARAMS ((struct bfd_link_info *info, asection *sec,
6298 asection * (*gc_mark_hook)
6299 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6300 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6302 static boolean elf_gc_sweep
6303 PARAMS ((struct bfd_link_info *info,
6304 boolean (*gc_sweep_hook)
6305 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6306 const Elf_Internal_Rela *relocs))));
6308 static boolean elf_gc_sweep_symbol
6309 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6311 static boolean elf_gc_allocate_got_offsets
6312 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6314 static boolean elf_gc_propagate_vtable_entries_used
6315 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6317 static boolean elf_gc_smash_unused_vtentry_relocs
6318 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6320 /* The mark phase of garbage collection. For a given section, mark
6321 it, and all the sections which define symbols to which it refers. */
6323 static boolean
6324 elf_gc_mark (info, sec, gc_mark_hook)
6325 struct bfd_link_info *info;
6326 asection *sec;
6327 asection * (*gc_mark_hook)
6328 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6329 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6331 boolean ret = true;
6333 sec->gc_mark = 1;
6335 /* Look through the section relocs. */
6337 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6339 Elf_Internal_Rela *relstart, *rel, *relend;
6340 Elf_Internal_Shdr *symtab_hdr;
6341 struct elf_link_hash_entry **sym_hashes;
6342 size_t nlocsyms;
6343 size_t extsymoff;
6344 Elf_External_Sym *locsyms, *freesyms = NULL;
6345 bfd *input_bfd = sec->owner;
6346 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6348 /* GCFIXME: how to arrange so that relocs and symbols are not
6349 reread continually? */
6351 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6352 sym_hashes = elf_sym_hashes (input_bfd);
6354 /* Read the local symbols. */
6355 if (elf_bad_symtab (input_bfd))
6357 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6358 extsymoff = 0;
6360 else
6361 extsymoff = nlocsyms = symtab_hdr->sh_info;
6362 if (symtab_hdr->contents)
6363 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6364 else if (nlocsyms == 0)
6365 locsyms = NULL;
6366 else
6368 locsyms = freesyms =
6369 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6370 if (freesyms == NULL
6371 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6372 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6373 nlocsyms, input_bfd)
6374 != nlocsyms * sizeof (Elf_External_Sym)))
6376 ret = false;
6377 goto out1;
6381 /* Read the relocations. */
6382 relstart = (NAME(_bfd_elf,link_read_relocs)
6383 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6384 info->keep_memory));
6385 if (relstart == NULL)
6387 ret = false;
6388 goto out1;
6390 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6392 for (rel = relstart; rel < relend; rel++)
6394 unsigned long r_symndx;
6395 asection *rsec;
6396 struct elf_link_hash_entry *h;
6397 Elf_Internal_Sym s;
6399 r_symndx = ELF_R_SYM (rel->r_info);
6400 if (r_symndx == 0)
6401 continue;
6403 if (elf_bad_symtab (sec->owner))
6405 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6406 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6407 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6408 else
6410 h = sym_hashes[r_symndx - extsymoff];
6411 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6414 else if (r_symndx >= nlocsyms)
6416 h = sym_hashes[r_symndx - extsymoff];
6417 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6419 else
6421 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6422 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6425 if (rsec && !rsec->gc_mark)
6426 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6428 ret = false;
6429 goto out2;
6433 out2:
6434 if (!info->keep_memory)
6435 free (relstart);
6436 out1:
6437 if (freesyms)
6438 free (freesyms);
6441 return ret;
6444 /* The sweep phase of garbage collection. Remove all garbage sections. */
6446 static boolean
6447 elf_gc_sweep (info, gc_sweep_hook)
6448 struct bfd_link_info *info;
6449 boolean (*gc_sweep_hook)
6450 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6451 const Elf_Internal_Rela *relocs));
6453 bfd *sub;
6455 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6457 asection *o;
6459 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6460 continue;
6462 for (o = sub->sections; o != NULL; o = o->next)
6464 /* Keep special sections. Keep .debug sections. */
6465 if ((o->flags & SEC_LINKER_CREATED)
6466 || (o->flags & SEC_DEBUGGING))
6467 o->gc_mark = 1;
6469 if (o->gc_mark)
6470 continue;
6472 /* Skip sweeping sections already excluded. */
6473 if (o->flags & SEC_EXCLUDE)
6474 continue;
6476 /* Since this is early in the link process, it is simple
6477 to remove a section from the output. */
6478 o->flags |= SEC_EXCLUDE;
6480 /* But we also have to update some of the relocation
6481 info we collected before. */
6482 if (gc_sweep_hook
6483 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6485 Elf_Internal_Rela *internal_relocs;
6486 boolean r;
6488 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6489 (o->owner, o, NULL, NULL, info->keep_memory));
6490 if (internal_relocs == NULL)
6491 return false;
6493 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6495 if (!info->keep_memory)
6496 free (internal_relocs);
6498 if (!r)
6499 return false;
6504 /* Remove the symbols that were in the swept sections from the dynamic
6505 symbol table. GCFIXME: Anyone know how to get them out of the
6506 static symbol table as well? */
6508 int i = 0;
6510 elf_link_hash_traverse (elf_hash_table (info),
6511 elf_gc_sweep_symbol,
6512 (PTR) &i);
6514 elf_hash_table (info)->dynsymcount = i;
6517 return true;
6520 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6522 static boolean
6523 elf_gc_sweep_symbol (h, idxptr)
6524 struct elf_link_hash_entry *h;
6525 PTR idxptr;
6527 int *idx = (int *) idxptr;
6529 if (h->dynindx != -1
6530 && ((h->root.type != bfd_link_hash_defined
6531 && h->root.type != bfd_link_hash_defweak)
6532 || h->root.u.def.section->gc_mark))
6533 h->dynindx = (*idx)++;
6535 return true;
6538 /* Propogate collected vtable information. This is called through
6539 elf_link_hash_traverse. */
6541 static boolean
6542 elf_gc_propagate_vtable_entries_used (h, okp)
6543 struct elf_link_hash_entry *h;
6544 PTR okp;
6546 /* Those that are not vtables. */
6547 if (h->vtable_parent == NULL)
6548 return true;
6550 /* Those vtables that do not have parents, we cannot merge. */
6551 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6552 return true;
6554 /* If we've already been done, exit. */
6555 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6556 return true;
6558 /* Make sure the parent's table is up to date. */
6559 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6561 if (h->vtable_entries_used == NULL)
6563 /* None of this table's entries were referenced. Re-use the
6564 parent's table. */
6565 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6566 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6568 else
6570 size_t n;
6571 boolean *cu, *pu;
6573 /* Or the parent's entries into ours. */
6574 cu = h->vtable_entries_used;
6575 cu[-1] = true;
6576 pu = h->vtable_parent->vtable_entries_used;
6577 if (pu != NULL)
6579 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6580 while (--n != 0)
6582 if (*pu) *cu = true;
6583 pu++, cu++;
6588 return true;
6591 static boolean
6592 elf_gc_smash_unused_vtentry_relocs (h, okp)
6593 struct elf_link_hash_entry *h;
6594 PTR okp;
6596 asection *sec;
6597 bfd_vma hstart, hend;
6598 Elf_Internal_Rela *relstart, *relend, *rel;
6599 struct elf_backend_data *bed;
6601 /* Take care of both those symbols that do not describe vtables as
6602 well as those that are not loaded. */
6603 if (h->vtable_parent == NULL)
6604 return true;
6606 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6607 || h->root.type == bfd_link_hash_defweak);
6609 sec = h->root.u.def.section;
6610 hstart = h->root.u.def.value;
6611 hend = hstart + h->size;
6613 relstart = (NAME(_bfd_elf,link_read_relocs)
6614 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6615 if (!relstart)
6616 return *(boolean *)okp = false;
6617 bed = get_elf_backend_data (sec->owner);
6618 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6620 for (rel = relstart; rel < relend; ++rel)
6621 if (rel->r_offset >= hstart && rel->r_offset < hend)
6623 /* If the entry is in use, do nothing. */
6624 if (h->vtable_entries_used
6625 && (rel->r_offset - hstart) < h->vtable_entries_size)
6627 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6628 if (h->vtable_entries_used[entry])
6629 continue;
6631 /* Otherwise, kill it. */
6632 rel->r_offset = rel->r_info = rel->r_addend = 0;
6635 return true;
6638 /* Do mark and sweep of unused sections. */
6640 boolean
6641 elf_gc_sections (abfd, info)
6642 bfd *abfd;
6643 struct bfd_link_info *info;
6645 boolean ok = true;
6646 bfd *sub;
6647 asection * (*gc_mark_hook)
6648 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6649 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6651 if (!get_elf_backend_data (abfd)->can_gc_sections
6652 || info->relocateable || info->emitrelocations
6653 || elf_hash_table (info)->dynamic_sections_created)
6654 return true;
6656 /* Apply transitive closure to the vtable entry usage info. */
6657 elf_link_hash_traverse (elf_hash_table (info),
6658 elf_gc_propagate_vtable_entries_used,
6659 (PTR) &ok);
6660 if (!ok)
6661 return false;
6663 /* Kill the vtable relocations that were not used. */
6664 elf_link_hash_traverse (elf_hash_table (info),
6665 elf_gc_smash_unused_vtentry_relocs,
6666 (PTR) &ok);
6667 if (!ok)
6668 return false;
6670 /* Grovel through relocs to find out who stays ... */
6672 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6673 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6675 asection *o;
6677 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6678 continue;
6680 for (o = sub->sections; o != NULL; o = o->next)
6682 if (o->flags & SEC_KEEP)
6683 if (!elf_gc_mark (info, o, gc_mark_hook))
6684 return false;
6688 /* ... and mark SEC_EXCLUDE for those that go. */
6689 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6690 return false;
6692 return true;
6695 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6697 boolean
6698 elf_gc_record_vtinherit (abfd, sec, h, offset)
6699 bfd *abfd;
6700 asection *sec;
6701 struct elf_link_hash_entry *h;
6702 bfd_vma offset;
6704 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6705 struct elf_link_hash_entry **search, *child;
6706 bfd_size_type extsymcount;
6708 /* The sh_info field of the symtab header tells us where the
6709 external symbols start. We don't care about the local symbols at
6710 this point. */
6711 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6712 if (!elf_bad_symtab (abfd))
6713 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6715 sym_hashes = elf_sym_hashes (abfd);
6716 sym_hashes_end = sym_hashes + extsymcount;
6718 /* Hunt down the child symbol, which is in this section at the same
6719 offset as the relocation. */
6720 for (search = sym_hashes; search != sym_hashes_end; ++search)
6722 if ((child = *search) != NULL
6723 && (child->root.type == bfd_link_hash_defined
6724 || child->root.type == bfd_link_hash_defweak)
6725 && child->root.u.def.section == sec
6726 && child->root.u.def.value == offset)
6727 goto win;
6730 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6731 bfd_get_filename (abfd), sec->name,
6732 (unsigned long)offset);
6733 bfd_set_error (bfd_error_invalid_operation);
6734 return false;
6736 win:
6737 if (!h)
6739 /* This *should* only be the absolute section. It could potentially
6740 be that someone has defined a non-global vtable though, which
6741 would be bad. It isn't worth paging in the local symbols to be
6742 sure though; that case should simply be handled by the assembler. */
6744 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6746 else
6747 child->vtable_parent = h;
6749 return true;
6752 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6754 boolean
6755 elf_gc_record_vtentry (abfd, sec, h, addend)
6756 bfd *abfd ATTRIBUTE_UNUSED;
6757 asection *sec ATTRIBUTE_UNUSED;
6758 struct elf_link_hash_entry *h;
6759 bfd_vma addend;
6761 if (addend >= h->vtable_entries_size)
6763 size_t size, bytes;
6764 boolean *ptr = h->vtable_entries_used;
6766 /* While the symbol is undefined, we have to be prepared to handle
6767 a zero size. */
6768 if (h->root.type == bfd_link_hash_undefined)
6769 size = addend;
6770 else
6772 size = h->size;
6773 if (size < addend)
6775 /* Oops! We've got a reference past the defined end of
6776 the table. This is probably a bug -- shall we warn? */
6777 size = addend;
6781 /* Allocate one extra entry for use as a "done" flag for the
6782 consolidation pass. */
6783 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6785 if (ptr)
6787 ptr = bfd_realloc (ptr - 1, bytes);
6789 if (ptr != NULL)
6791 size_t oldbytes;
6793 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6794 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6797 else
6798 ptr = bfd_zmalloc (bytes);
6800 if (ptr == NULL)
6801 return false;
6803 /* And arrange for that done flag to be at index -1. */
6804 h->vtable_entries_used = ptr + 1;
6805 h->vtable_entries_size = size;
6808 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6810 return true;
6813 /* And an accompanying bit to work out final got entry offsets once
6814 we're done. Should be called from final_link. */
6816 boolean
6817 elf_gc_common_finalize_got_offsets (abfd, info)
6818 bfd *abfd;
6819 struct bfd_link_info *info;
6821 bfd *i;
6822 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6823 bfd_vma gotoff;
6825 /* The GOT offset is relative to the .got section, but the GOT header is
6826 put into the .got.plt section, if the backend uses it. */
6827 if (bed->want_got_plt)
6828 gotoff = 0;
6829 else
6830 gotoff = bed->got_header_size;
6832 /* Do the local .got entries first. */
6833 for (i = info->input_bfds; i; i = i->link_next)
6835 bfd_signed_vma *local_got;
6836 bfd_size_type j, locsymcount;
6837 Elf_Internal_Shdr *symtab_hdr;
6839 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6840 continue;
6842 local_got = elf_local_got_refcounts (i);
6843 if (!local_got)
6844 continue;
6846 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6847 if (elf_bad_symtab (i))
6848 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6849 else
6850 locsymcount = symtab_hdr->sh_info;
6852 for (j = 0; j < locsymcount; ++j)
6854 if (local_got[j] > 0)
6856 local_got[j] = gotoff;
6857 gotoff += ARCH_SIZE / 8;
6859 else
6860 local_got[j] = (bfd_vma) -1;
6864 /* Then the global .got entries. .plt refcounts are handled by
6865 adjust_dynamic_symbol */
6866 elf_link_hash_traverse (elf_hash_table (info),
6867 elf_gc_allocate_got_offsets,
6868 (PTR) &gotoff);
6869 return true;
6872 /* We need a special top-level link routine to convert got reference counts
6873 to real got offsets. */
6875 static boolean
6876 elf_gc_allocate_got_offsets (h, offarg)
6877 struct elf_link_hash_entry *h;
6878 PTR offarg;
6880 bfd_vma *off = (bfd_vma *) offarg;
6882 if (h->got.refcount > 0)
6884 h->got.offset = off[0];
6885 off[0] += ARCH_SIZE / 8;
6887 else
6888 h->got.offset = (bfd_vma) -1;
6890 return true;
6893 /* Many folk need no more in the way of final link than this, once
6894 got entry reference counting is enabled. */
6896 boolean
6897 elf_gc_common_final_link (abfd, info)
6898 bfd *abfd;
6899 struct bfd_link_info *info;
6901 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6902 return false;
6904 /* Invoke the regular ELF backend linker to do all the work. */
6905 return elf_bfd_final_link (abfd, info);
6908 /* This function will be called though elf_link_hash_traverse to store
6909 all hash value of the exported symbols in an array. */
6911 static boolean
6912 elf_collect_hash_codes (h, data)
6913 struct elf_link_hash_entry *h;
6914 PTR data;
6916 unsigned long **valuep = (unsigned long **) data;
6917 const char *name;
6918 char *p;
6919 unsigned long ha;
6920 char *alc = NULL;
6922 /* Ignore indirect symbols. These are added by the versioning code. */
6923 if (h->dynindx == -1)
6924 return true;
6926 name = h->root.root.string;
6927 p = strchr (name, ELF_VER_CHR);
6928 if (p != NULL)
6930 alc = bfd_malloc (p - name + 1);
6931 memcpy (alc, name, p - name);
6932 alc[p - name] = '\0';
6933 name = alc;
6936 /* Compute the hash value. */
6937 ha = bfd_elf_hash (name);
6939 /* Store the found hash value in the array given as the argument. */
6940 *(*valuep)++ = ha;
6942 /* And store it in the struct so that we can put it in the hash table
6943 later. */
6944 h->elf_hash_value = ha;
6946 if (alc != NULL)
6947 free (alc);
6949 return true;