* elf-bfd.h (struct elf_backend_data): Add action_discarded.
[binutils.git] / bfd / elflink.c
blob092119aa0be5f6d62287a568c5557a0843557c51
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
3 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
30 bfd_boolean
31 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
33 flagword flags;
34 asection *s;
35 struct elf_link_hash_entry *h;
36 struct bfd_link_hash_entry *bh;
37 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
38 int ptralign;
40 /* This function may be called more than once. */
41 s = bfd_get_section_by_name (abfd, ".got");
42 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
43 return TRUE;
45 switch (bed->s->arch_size)
47 case 32:
48 ptralign = 2;
49 break;
51 case 64:
52 ptralign = 3;
53 break;
55 default:
56 bfd_set_error (bfd_error_bad_value);
57 return FALSE;
60 flags = bed->dynamic_sec_flags;
62 s = bfd_make_section_with_flags (abfd, ".got", flags);
63 if (s == NULL
64 || !bfd_set_section_alignment (abfd, s, ptralign))
65 return FALSE;
67 if (bed->want_got_plt)
69 s = bfd_make_section_with_flags (abfd, ".got.plt", flags);
70 if (s == NULL
71 || !bfd_set_section_alignment (abfd, s, ptralign))
72 return FALSE;
75 if (bed->want_got_sym)
77 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
78 (or .got.plt) section. We don't do this in the linker script
79 because we don't want to define the symbol if we are not creating
80 a global offset table. */
81 bh = NULL;
82 if (!(_bfd_generic_link_add_one_symbol
83 (info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s,
84 0, NULL, FALSE, bed->collect, &bh)))
85 return FALSE;
86 h = (struct elf_link_hash_entry *) bh;
87 h->def_regular = 1;
88 h->type = STT_OBJECT;
89 h->other = STV_HIDDEN;
91 if (! info->executable
92 && ! bfd_elf_link_record_dynamic_symbol (info, h))
93 return FALSE;
95 elf_hash_table (info)->hgot = h;
98 /* The first bit of the global offset table is the header. */
99 s->size += bed->got_header_size;
101 return TRUE;
104 /* Create a strtab to hold the dynamic symbol names. */
105 static bfd_boolean
106 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
108 struct elf_link_hash_table *hash_table;
110 hash_table = elf_hash_table (info);
111 if (hash_table->dynobj == NULL)
112 hash_table->dynobj = abfd;
114 if (hash_table->dynstr == NULL)
116 hash_table->dynstr = _bfd_elf_strtab_init ();
117 if (hash_table->dynstr == NULL)
118 return FALSE;
120 return TRUE;
123 /* Create some sections which will be filled in with dynamic linking
124 information. ABFD is an input file which requires dynamic sections
125 to be created. The dynamic sections take up virtual memory space
126 when the final executable is run, so we need to create them before
127 addresses are assigned to the output sections. We work out the
128 actual contents and size of these sections later. */
130 bfd_boolean
131 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
133 flagword flags;
134 register asection *s;
135 struct elf_link_hash_entry *h;
136 struct bfd_link_hash_entry *bh;
137 const struct elf_backend_data *bed;
139 if (! is_elf_hash_table (info->hash))
140 return FALSE;
142 if (elf_hash_table (info)->dynamic_sections_created)
143 return TRUE;
145 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
146 return FALSE;
148 abfd = elf_hash_table (info)->dynobj;
149 bed = get_elf_backend_data (abfd);
151 flags = bed->dynamic_sec_flags;
153 /* A dynamically linked executable has a .interp section, but a
154 shared library does not. */
155 if (info->executable)
157 s = bfd_make_section_with_flags (abfd, ".interp",
158 flags | SEC_READONLY);
159 if (s == NULL)
160 return FALSE;
163 if (! info->traditional_format)
165 s = bfd_make_section_with_flags (abfd, ".eh_frame_hdr",
166 flags | SEC_READONLY);
167 if (s == NULL
168 || ! bfd_set_section_alignment (abfd, s, 2))
169 return FALSE;
170 elf_hash_table (info)->eh_info.hdr_sec = s;
173 /* Create sections to hold version informations. These are removed
174 if they are not needed. */
175 s = bfd_make_section_with_flags (abfd, ".gnu.version_d",
176 flags | SEC_READONLY);
177 if (s == NULL
178 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
179 return FALSE;
181 s = bfd_make_section_with_flags (abfd, ".gnu.version",
182 flags | SEC_READONLY);
183 if (s == NULL
184 || ! bfd_set_section_alignment (abfd, s, 1))
185 return FALSE;
187 s = bfd_make_section_with_flags (abfd, ".gnu.version_r",
188 flags | SEC_READONLY);
189 if (s == NULL
190 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
191 return FALSE;
193 s = bfd_make_section_with_flags (abfd, ".dynsym",
194 flags | SEC_READONLY);
195 if (s == NULL
196 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
197 return FALSE;
199 s = bfd_make_section_with_flags (abfd, ".dynstr",
200 flags | SEC_READONLY);
201 if (s == NULL)
202 return FALSE;
204 s = bfd_make_section_with_flags (abfd, ".dynamic", flags);
205 if (s == NULL
206 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
207 return FALSE;
209 /* The special symbol _DYNAMIC is always set to the start of the
210 .dynamic section. We could set _DYNAMIC in a linker script, but we
211 only want to define it if we are, in fact, creating a .dynamic
212 section. We don't want to define it if there is no .dynamic
213 section, since on some ELF platforms the start up code examines it
214 to decide how to initialize the process. */
215 h = elf_link_hash_lookup (elf_hash_table (info), "_DYNAMIC",
216 FALSE, FALSE, FALSE);
217 if (h != NULL)
219 /* Zap symbol defined in an as-needed lib that wasn't linked.
220 This is a symptom of a larger problem: Absolute symbols
221 defined in shared libraries can't be overridden, because we
222 lose the link to the bfd which is via the symbol section. */
223 h->root.type = bfd_link_hash_new;
225 bh = &h->root;
226 if (! (_bfd_generic_link_add_one_symbol
227 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, 0, NULL, FALSE,
228 get_elf_backend_data (abfd)->collect, &bh)))
229 return FALSE;
230 h = (struct elf_link_hash_entry *) bh;
231 h->def_regular = 1;
232 h->type = STT_OBJECT;
234 if (! info->executable
235 && ! bfd_elf_link_record_dynamic_symbol (info, h))
236 return FALSE;
238 s = bfd_make_section_with_flags (abfd, ".hash",
239 flags | SEC_READONLY);
240 if (s == NULL
241 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
242 return FALSE;
243 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
245 /* Let the backend create the rest of the sections. This lets the
246 backend set the right flags. The backend will normally create
247 the .got and .plt sections. */
248 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
249 return FALSE;
251 elf_hash_table (info)->dynamic_sections_created = TRUE;
253 return TRUE;
256 /* Create dynamic sections when linking against a dynamic object. */
258 bfd_boolean
259 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
261 flagword flags, pltflags;
262 asection *s;
263 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
265 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
266 .rel[a].bss sections. */
267 flags = bed->dynamic_sec_flags;
269 pltflags = flags;
270 if (bed->plt_not_loaded)
271 /* We do not clear SEC_ALLOC here because we still want the OS to
272 allocate space for the section; it's just that there's nothing
273 to read in from the object file. */
274 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
275 else
276 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
277 if (bed->plt_readonly)
278 pltflags |= SEC_READONLY;
280 s = bfd_make_section_with_flags (abfd, ".plt", pltflags);
281 if (s == NULL
282 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
283 return FALSE;
285 if (bed->want_plt_sym)
287 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
288 .plt section. */
289 struct elf_link_hash_entry *h;
290 struct bfd_link_hash_entry *bh = NULL;
292 if (! (_bfd_generic_link_add_one_symbol
293 (info, abfd, "_PROCEDURE_LINKAGE_TABLE_", BSF_GLOBAL, s, 0, NULL,
294 FALSE, get_elf_backend_data (abfd)->collect, &bh)))
295 return FALSE;
296 h = (struct elf_link_hash_entry *) bh;
297 h->def_regular = 1;
298 h->type = STT_OBJECT;
300 if (! info->executable
301 && ! bfd_elf_link_record_dynamic_symbol (info, h))
302 return FALSE;
305 s = bfd_make_section_with_flags (abfd,
306 (bed->default_use_rela_p
307 ? ".rela.plt" : ".rel.plt"),
308 flags | SEC_READONLY);
309 if (s == NULL
310 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
311 return FALSE;
313 if (! _bfd_elf_create_got_section (abfd, info))
314 return FALSE;
316 if (bed->want_dynbss)
318 /* The .dynbss section is a place to put symbols which are defined
319 by dynamic objects, are referenced by regular objects, and are
320 not functions. We must allocate space for them in the process
321 image and use a R_*_COPY reloc to tell the dynamic linker to
322 initialize them at run time. The linker script puts the .dynbss
323 section into the .bss section of the final image. */
324 s = bfd_make_section_with_flags (abfd, ".dynbss",
325 (SEC_ALLOC
326 | SEC_LINKER_CREATED));
327 if (s == NULL)
328 return FALSE;
330 /* The .rel[a].bss section holds copy relocs. This section is not
331 normally needed. We need to create it here, though, so that the
332 linker will map it to an output section. We can't just create it
333 only if we need it, because we will not know whether we need it
334 until we have seen all the input files, and the first time the
335 main linker code calls BFD after examining all the input files
336 (size_dynamic_sections) the input sections have already been
337 mapped to the output sections. If the section turns out not to
338 be needed, we can discard it later. We will never need this
339 section when generating a shared object, since they do not use
340 copy relocs. */
341 if (! info->shared)
343 s = bfd_make_section_with_flags (abfd,
344 (bed->default_use_rela_p
345 ? ".rela.bss" : ".rel.bss"),
346 flags | SEC_READONLY);
347 if (s == NULL
348 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
349 return FALSE;
353 return TRUE;
356 /* Record a new dynamic symbol. We record the dynamic symbols as we
357 read the input files, since we need to have a list of all of them
358 before we can determine the final sizes of the output sections.
359 Note that we may actually call this function even though we are not
360 going to output any dynamic symbols; in some cases we know that a
361 symbol should be in the dynamic symbol table, but only if there is
362 one. */
364 bfd_boolean
365 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
366 struct elf_link_hash_entry *h)
368 if (h->dynindx == -1)
370 struct elf_strtab_hash *dynstr;
371 char *p;
372 const char *name;
373 bfd_size_type indx;
375 /* XXX: The ABI draft says the linker must turn hidden and
376 internal symbols into STB_LOCAL symbols when producing the
377 DSO. However, if ld.so honors st_other in the dynamic table,
378 this would not be necessary. */
379 switch (ELF_ST_VISIBILITY (h->other))
381 case STV_INTERNAL:
382 case STV_HIDDEN:
383 if (h->root.type != bfd_link_hash_undefined
384 && h->root.type != bfd_link_hash_undefweak)
386 h->forced_local = 1;
387 if (!elf_hash_table (info)->is_relocatable_executable)
388 return TRUE;
391 default:
392 break;
395 h->dynindx = elf_hash_table (info)->dynsymcount;
396 ++elf_hash_table (info)->dynsymcount;
398 dynstr = elf_hash_table (info)->dynstr;
399 if (dynstr == NULL)
401 /* Create a strtab to hold the dynamic symbol names. */
402 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
403 if (dynstr == NULL)
404 return FALSE;
407 /* We don't put any version information in the dynamic string
408 table. */
409 name = h->root.root.string;
410 p = strchr (name, ELF_VER_CHR);
411 if (p != NULL)
412 /* We know that the p points into writable memory. In fact,
413 there are only a few symbols that have read-only names, being
414 those like _GLOBAL_OFFSET_TABLE_ that are created specially
415 by the backends. Most symbols will have names pointing into
416 an ELF string table read from a file, or to objalloc memory. */
417 *p = 0;
419 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
421 if (p != NULL)
422 *p = ELF_VER_CHR;
424 if (indx == (bfd_size_type) -1)
425 return FALSE;
426 h->dynstr_index = indx;
429 return TRUE;
432 /* Record an assignment to a symbol made by a linker script. We need
433 this in case some dynamic object refers to this symbol. */
435 bfd_boolean
436 bfd_elf_record_link_assignment (struct bfd_link_info *info,
437 const char *name,
438 bfd_boolean provide)
440 struct elf_link_hash_entry *h;
441 struct elf_link_hash_table *htab;
443 if (!is_elf_hash_table (info->hash))
444 return TRUE;
446 htab = elf_hash_table (info);
447 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
448 if (h == NULL)
449 return provide;
451 /* Since we're defining the symbol, don't let it seem to have not
452 been defined. record_dynamic_symbol and size_dynamic_sections
453 may depend on this. */
454 if (h->root.type == bfd_link_hash_undefweak
455 || h->root.type == bfd_link_hash_undefined)
457 h->root.type = bfd_link_hash_new;
458 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
459 bfd_link_repair_undef_list (&htab->root);
462 if (h->root.type == bfd_link_hash_new)
463 h->non_elf = 0;
465 /* If this symbol is being provided by the linker script, and it is
466 currently defined by a dynamic object, but not by a regular
467 object, then mark it as undefined so that the generic linker will
468 force the correct value. */
469 if (provide
470 && h->def_dynamic
471 && !h->def_regular)
472 h->root.type = bfd_link_hash_undefined;
474 /* If this symbol is not being provided by the linker script, and it is
475 currently defined by a dynamic object, but not by a regular object,
476 then clear out any version information because the symbol will not be
477 associated with the dynamic object any more. */
478 if (!provide
479 && h->def_dynamic
480 && !h->def_regular)
481 h->verinfo.verdef = NULL;
483 h->def_regular = 1;
485 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
486 and executables. */
487 if (!info->relocatable
488 && h->dynindx != -1
489 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
490 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
491 h->forced_local = 1;
493 if ((h->def_dynamic
494 || h->ref_dynamic
495 || info->shared
496 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
497 && h->dynindx == -1)
499 if (! bfd_elf_link_record_dynamic_symbol (info, h))
500 return FALSE;
502 /* If this is a weak defined symbol, and we know a corresponding
503 real symbol from the same dynamic object, make sure the real
504 symbol is also made into a dynamic symbol. */
505 if (h->u.weakdef != NULL
506 && h->u.weakdef->dynindx == -1)
508 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
509 return FALSE;
513 return TRUE;
516 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
517 success, and 2 on a failure caused by attempting to record a symbol
518 in a discarded section, eg. a discarded link-once section symbol. */
521 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
522 bfd *input_bfd,
523 long input_indx)
525 bfd_size_type amt;
526 struct elf_link_local_dynamic_entry *entry;
527 struct elf_link_hash_table *eht;
528 struct elf_strtab_hash *dynstr;
529 unsigned long dynstr_index;
530 char *name;
531 Elf_External_Sym_Shndx eshndx;
532 char esym[sizeof (Elf64_External_Sym)];
534 if (! is_elf_hash_table (info->hash))
535 return 0;
537 /* See if the entry exists already. */
538 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
539 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
540 return 1;
542 amt = sizeof (*entry);
543 entry = bfd_alloc (input_bfd, amt);
544 if (entry == NULL)
545 return 0;
547 /* Go find the symbol, so that we can find it's name. */
548 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
549 1, input_indx, &entry->isym, esym, &eshndx))
551 bfd_release (input_bfd, entry);
552 return 0;
555 if (entry->isym.st_shndx != SHN_UNDEF
556 && (entry->isym.st_shndx < SHN_LORESERVE
557 || entry->isym.st_shndx > SHN_HIRESERVE))
559 asection *s;
561 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
562 if (s == NULL || bfd_is_abs_section (s->output_section))
564 /* We can still bfd_release here as nothing has done another
565 bfd_alloc. We can't do this later in this function. */
566 bfd_release (input_bfd, entry);
567 return 2;
571 name = (bfd_elf_string_from_elf_section
572 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
573 entry->isym.st_name));
575 dynstr = elf_hash_table (info)->dynstr;
576 if (dynstr == NULL)
578 /* Create a strtab to hold the dynamic symbol names. */
579 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
580 if (dynstr == NULL)
581 return 0;
584 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
585 if (dynstr_index == (unsigned long) -1)
586 return 0;
587 entry->isym.st_name = dynstr_index;
589 eht = elf_hash_table (info);
591 entry->next = eht->dynlocal;
592 eht->dynlocal = entry;
593 entry->input_bfd = input_bfd;
594 entry->input_indx = input_indx;
595 eht->dynsymcount++;
597 /* Whatever binding the symbol had before, it's now local. */
598 entry->isym.st_info
599 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
601 /* The dynindx will be set at the end of size_dynamic_sections. */
603 return 1;
606 /* Return the dynindex of a local dynamic symbol. */
608 long
609 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
610 bfd *input_bfd,
611 long input_indx)
613 struct elf_link_local_dynamic_entry *e;
615 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
616 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
617 return e->dynindx;
618 return -1;
621 /* This function is used to renumber the dynamic symbols, if some of
622 them are removed because they are marked as local. This is called
623 via elf_link_hash_traverse. */
625 static bfd_boolean
626 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
627 void *data)
629 size_t *count = data;
631 if (h->root.type == bfd_link_hash_warning)
632 h = (struct elf_link_hash_entry *) h->root.u.i.link;
634 if (h->forced_local)
635 return TRUE;
637 if (h->dynindx != -1)
638 h->dynindx = ++(*count);
640 return TRUE;
644 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
645 STB_LOCAL binding. */
647 static bfd_boolean
648 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
649 void *data)
651 size_t *count = data;
653 if (h->root.type == bfd_link_hash_warning)
654 h = (struct elf_link_hash_entry *) h->root.u.i.link;
656 if (!h->forced_local)
657 return TRUE;
659 if (h->dynindx != -1)
660 h->dynindx = ++(*count);
662 return TRUE;
665 /* Return true if the dynamic symbol for a given section should be
666 omitted when creating a shared library. */
667 bfd_boolean
668 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
669 struct bfd_link_info *info,
670 asection *p)
672 switch (elf_section_data (p)->this_hdr.sh_type)
674 case SHT_PROGBITS:
675 case SHT_NOBITS:
676 /* If sh_type is yet undecided, assume it could be
677 SHT_PROGBITS/SHT_NOBITS. */
678 case SHT_NULL:
679 if (strcmp (p->name, ".got") == 0
680 || strcmp (p->name, ".got.plt") == 0
681 || strcmp (p->name, ".plt") == 0)
683 asection *ip;
684 bfd *dynobj = elf_hash_table (info)->dynobj;
686 if (dynobj != NULL
687 && (ip = bfd_get_section_by_name (dynobj, p->name)) != NULL
688 && (ip->flags & SEC_LINKER_CREATED)
689 && ip->output_section == p)
690 return TRUE;
692 return FALSE;
694 /* There shouldn't be section relative relocations
695 against any other section. */
696 default:
697 return TRUE;
701 /* Assign dynsym indices. In a shared library we generate a section
702 symbol for each output section, which come first. Next come symbols
703 which have been forced to local binding. Then all of the back-end
704 allocated local dynamic syms, followed by the rest of the global
705 symbols. */
707 static unsigned long
708 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
709 struct bfd_link_info *info,
710 unsigned long *section_sym_count)
712 unsigned long dynsymcount = 0;
714 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
716 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
717 asection *p;
718 for (p = output_bfd->sections; p ; p = p->next)
719 if ((p->flags & SEC_EXCLUDE) == 0
720 && (p->flags & SEC_ALLOC) != 0
721 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
722 elf_section_data (p)->dynindx = ++dynsymcount;
724 *section_sym_count = dynsymcount;
726 elf_link_hash_traverse (elf_hash_table (info),
727 elf_link_renumber_local_hash_table_dynsyms,
728 &dynsymcount);
730 if (elf_hash_table (info)->dynlocal)
732 struct elf_link_local_dynamic_entry *p;
733 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
734 p->dynindx = ++dynsymcount;
737 elf_link_hash_traverse (elf_hash_table (info),
738 elf_link_renumber_hash_table_dynsyms,
739 &dynsymcount);
741 /* There is an unused NULL entry at the head of the table which
742 we must account for in our count. Unless there weren't any
743 symbols, which means we'll have no table at all. */
744 if (dynsymcount != 0)
745 ++dynsymcount;
747 return elf_hash_table (info)->dynsymcount = dynsymcount;
750 /* This function is called when we want to define a new symbol. It
751 handles the various cases which arise when we find a definition in
752 a dynamic object, or when there is already a definition in a
753 dynamic object. The new symbol is described by NAME, SYM, PSEC,
754 and PVALUE. We set SYM_HASH to the hash table entry. We set
755 OVERRIDE if the old symbol is overriding a new definition. We set
756 TYPE_CHANGE_OK if it is OK for the type to change. We set
757 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
758 change, we mean that we shouldn't warn if the type or size does
759 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
760 object is overridden by a regular object. */
762 bfd_boolean
763 _bfd_elf_merge_symbol (bfd *abfd,
764 struct bfd_link_info *info,
765 const char *name,
766 Elf_Internal_Sym *sym,
767 asection **psec,
768 bfd_vma *pvalue,
769 unsigned int *pold_alignment,
770 struct elf_link_hash_entry **sym_hash,
771 bfd_boolean *skip,
772 bfd_boolean *override,
773 bfd_boolean *type_change_ok,
774 bfd_boolean *size_change_ok)
776 asection *sec, *oldsec;
777 struct elf_link_hash_entry *h;
778 struct elf_link_hash_entry *flip;
779 int bind;
780 bfd *oldbfd;
781 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
782 bfd_boolean newweak, oldweak;
783 const struct elf_backend_data *bed;
785 *skip = FALSE;
786 *override = FALSE;
788 sec = *psec;
789 bind = ELF_ST_BIND (sym->st_info);
791 if (! bfd_is_und_section (sec))
792 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
793 else
794 h = ((struct elf_link_hash_entry *)
795 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
796 if (h == NULL)
797 return FALSE;
798 *sym_hash = h;
800 /* This code is for coping with dynamic objects, and is only useful
801 if we are doing an ELF link. */
802 if (info->hash->creator != abfd->xvec)
803 return TRUE;
805 /* For merging, we only care about real symbols. */
807 while (h->root.type == bfd_link_hash_indirect
808 || h->root.type == bfd_link_hash_warning)
809 h = (struct elf_link_hash_entry *) h->root.u.i.link;
811 /* If we just created the symbol, mark it as being an ELF symbol.
812 Other than that, there is nothing to do--there is no merge issue
813 with a newly defined symbol--so we just return. */
815 if (h->root.type == bfd_link_hash_new)
817 h->non_elf = 0;
818 return TRUE;
821 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
822 existing symbol. */
824 switch (h->root.type)
826 default:
827 oldbfd = NULL;
828 oldsec = NULL;
829 break;
831 case bfd_link_hash_undefined:
832 case bfd_link_hash_undefweak:
833 oldbfd = h->root.u.undef.abfd;
834 oldsec = NULL;
835 break;
837 case bfd_link_hash_defined:
838 case bfd_link_hash_defweak:
839 oldbfd = h->root.u.def.section->owner;
840 oldsec = h->root.u.def.section;
841 break;
843 case bfd_link_hash_common:
844 oldbfd = h->root.u.c.p->section->owner;
845 oldsec = h->root.u.c.p->section;
846 break;
849 /* In cases involving weak versioned symbols, we may wind up trying
850 to merge a symbol with itself. Catch that here, to avoid the
851 confusion that results if we try to override a symbol with
852 itself. The additional tests catch cases like
853 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
854 dynamic object, which we do want to handle here. */
855 if (abfd == oldbfd
856 && ((abfd->flags & DYNAMIC) == 0
857 || !h->def_regular))
858 return TRUE;
860 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
861 respectively, is from a dynamic object. */
863 if ((abfd->flags & DYNAMIC) != 0)
864 newdyn = TRUE;
865 else
866 newdyn = FALSE;
868 if (oldbfd != NULL)
869 olddyn = (oldbfd->flags & DYNAMIC) != 0;
870 else
872 asection *hsec;
874 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
875 indices used by MIPS ELF. */
876 switch (h->root.type)
878 default:
879 hsec = NULL;
880 break;
882 case bfd_link_hash_defined:
883 case bfd_link_hash_defweak:
884 hsec = h->root.u.def.section;
885 break;
887 case bfd_link_hash_common:
888 hsec = h->root.u.c.p->section;
889 break;
892 if (hsec == NULL)
893 olddyn = FALSE;
894 else
895 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
898 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
899 respectively, appear to be a definition rather than reference. */
901 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
902 newdef = FALSE;
903 else
904 newdef = TRUE;
906 if (h->root.type == bfd_link_hash_undefined
907 || h->root.type == bfd_link_hash_undefweak
908 || h->root.type == bfd_link_hash_common)
909 olddef = FALSE;
910 else
911 olddef = TRUE;
913 /* Check TLS symbol. */
914 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
915 && ELF_ST_TYPE (sym->st_info) != h->type)
917 bfd *ntbfd, *tbfd;
918 bfd_boolean ntdef, tdef;
919 asection *ntsec, *tsec;
921 if (h->type == STT_TLS)
923 ntbfd = abfd;
924 ntsec = sec;
925 ntdef = newdef;
926 tbfd = oldbfd;
927 tsec = oldsec;
928 tdef = olddef;
930 else
932 ntbfd = oldbfd;
933 ntsec = oldsec;
934 ntdef = olddef;
935 tbfd = abfd;
936 tsec = sec;
937 tdef = newdef;
940 if (tdef && ntdef)
941 (*_bfd_error_handler)
942 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
943 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
944 else if (!tdef && !ntdef)
945 (*_bfd_error_handler)
946 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
947 tbfd, ntbfd, h->root.root.string);
948 else if (tdef)
949 (*_bfd_error_handler)
950 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
951 tbfd, tsec, ntbfd, h->root.root.string);
952 else
953 (*_bfd_error_handler)
954 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
955 tbfd, ntbfd, ntsec, h->root.root.string);
957 bfd_set_error (bfd_error_bad_value);
958 return FALSE;
961 /* We need to remember if a symbol has a definition in a dynamic
962 object or is weak in all dynamic objects. Internal and hidden
963 visibility will make it unavailable to dynamic objects. */
964 if (newdyn && !h->dynamic_def)
966 if (!bfd_is_und_section (sec))
967 h->dynamic_def = 1;
968 else
970 /* Check if this symbol is weak in all dynamic objects. If it
971 is the first time we see it in a dynamic object, we mark
972 if it is weak. Otherwise, we clear it. */
973 if (!h->ref_dynamic)
975 if (bind == STB_WEAK)
976 h->dynamic_weak = 1;
978 else if (bind != STB_WEAK)
979 h->dynamic_weak = 0;
983 /* If the old symbol has non-default visibility, we ignore the new
984 definition from a dynamic object. */
985 if (newdyn
986 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
987 && !bfd_is_und_section (sec))
989 *skip = TRUE;
990 /* Make sure this symbol is dynamic. */
991 h->ref_dynamic = 1;
992 /* A protected symbol has external availability. Make sure it is
993 recorded as dynamic.
995 FIXME: Should we check type and size for protected symbol? */
996 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
997 return bfd_elf_link_record_dynamic_symbol (info, h);
998 else
999 return TRUE;
1001 else if (!newdyn
1002 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1003 && h->def_dynamic)
1005 /* If the new symbol with non-default visibility comes from a
1006 relocatable file and the old definition comes from a dynamic
1007 object, we remove the old definition. */
1008 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1009 h = *sym_hash;
1011 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1012 && bfd_is_und_section (sec))
1014 /* If the new symbol is undefined and the old symbol was
1015 also undefined before, we need to make sure
1016 _bfd_generic_link_add_one_symbol doesn't mess
1017 up the linker hash table undefs list. Since the old
1018 definition came from a dynamic object, it is still on the
1019 undefs list. */
1020 h->root.type = bfd_link_hash_undefined;
1021 h->root.u.undef.abfd = abfd;
1023 else
1025 h->root.type = bfd_link_hash_new;
1026 h->root.u.undef.abfd = NULL;
1029 if (h->def_dynamic)
1031 h->def_dynamic = 0;
1032 h->ref_dynamic = 1;
1033 h->dynamic_def = 1;
1035 /* FIXME: Should we check type and size for protected symbol? */
1036 h->size = 0;
1037 h->type = 0;
1038 return TRUE;
1041 /* Differentiate strong and weak symbols. */
1042 newweak = bind == STB_WEAK;
1043 oldweak = (h->root.type == bfd_link_hash_defweak
1044 || h->root.type == bfd_link_hash_undefweak);
1046 /* If a new weak symbol definition comes from a regular file and the
1047 old symbol comes from a dynamic library, we treat the new one as
1048 strong. Similarly, an old weak symbol definition from a regular
1049 file is treated as strong when the new symbol comes from a dynamic
1050 library. Further, an old weak symbol from a dynamic library is
1051 treated as strong if the new symbol is from a dynamic library.
1052 This reflects the way glibc's ld.so works.
1054 Do this before setting *type_change_ok or *size_change_ok so that
1055 we warn properly when dynamic library symbols are overridden. */
1057 if (newdef && !newdyn && olddyn)
1058 newweak = FALSE;
1059 if (olddef && newdyn)
1060 oldweak = FALSE;
1062 /* It's OK to change the type if either the existing symbol or the
1063 new symbol is weak. A type change is also OK if the old symbol
1064 is undefined and the new symbol is defined. */
1066 if (oldweak
1067 || newweak
1068 || (newdef
1069 && h->root.type == bfd_link_hash_undefined))
1070 *type_change_ok = TRUE;
1072 /* It's OK to change the size if either the existing symbol or the
1073 new symbol is weak, or if the old symbol is undefined. */
1075 if (*type_change_ok
1076 || h->root.type == bfd_link_hash_undefined)
1077 *size_change_ok = TRUE;
1079 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1080 symbol, respectively, appears to be a common symbol in a dynamic
1081 object. If a symbol appears in an uninitialized section, and is
1082 not weak, and is not a function, then it may be a common symbol
1083 which was resolved when the dynamic object was created. We want
1084 to treat such symbols specially, because they raise special
1085 considerations when setting the symbol size: if the symbol
1086 appears as a common symbol in a regular object, and the size in
1087 the regular object is larger, we must make sure that we use the
1088 larger size. This problematic case can always be avoided in C,
1089 but it must be handled correctly when using Fortran shared
1090 libraries.
1092 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1093 likewise for OLDDYNCOMMON and OLDDEF.
1095 Note that this test is just a heuristic, and that it is quite
1096 possible to have an uninitialized symbol in a shared object which
1097 is really a definition, rather than a common symbol. This could
1098 lead to some minor confusion when the symbol really is a common
1099 symbol in some regular object. However, I think it will be
1100 harmless. */
1102 if (newdyn
1103 && newdef
1104 && !newweak
1105 && (sec->flags & SEC_ALLOC) != 0
1106 && (sec->flags & SEC_LOAD) == 0
1107 && sym->st_size > 0
1108 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1109 newdyncommon = TRUE;
1110 else
1111 newdyncommon = FALSE;
1113 if (olddyn
1114 && olddef
1115 && h->root.type == bfd_link_hash_defined
1116 && h->def_dynamic
1117 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1118 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1119 && h->size > 0
1120 && h->type != STT_FUNC)
1121 olddyncommon = TRUE;
1122 else
1123 olddyncommon = FALSE;
1125 /* We now know everything about the old and new symbols. We ask the
1126 backend to check if we can merge them. */
1127 bed = get_elf_backend_data (abfd);
1128 if (bed->merge_symbol
1129 && !bed->merge_symbol (info, sym_hash, h, sym, psec, pvalue,
1130 pold_alignment, skip, override,
1131 type_change_ok, size_change_ok,
1132 &newdyn, &newdef, &newdyncommon, &newweak,
1133 abfd, &sec,
1134 &olddyn, &olddef, &olddyncommon, &oldweak,
1135 oldbfd, &oldsec))
1136 return FALSE;
1138 /* If both the old and the new symbols look like common symbols in a
1139 dynamic object, set the size of the symbol to the larger of the
1140 two. */
1142 if (olddyncommon
1143 && newdyncommon
1144 && sym->st_size != h->size)
1146 /* Since we think we have two common symbols, issue a multiple
1147 common warning if desired. Note that we only warn if the
1148 size is different. If the size is the same, we simply let
1149 the old symbol override the new one as normally happens with
1150 symbols defined in dynamic objects. */
1152 if (! ((*info->callbacks->multiple_common)
1153 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1154 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1155 return FALSE;
1157 if (sym->st_size > h->size)
1158 h->size = sym->st_size;
1160 *size_change_ok = TRUE;
1163 /* If we are looking at a dynamic object, and we have found a
1164 definition, we need to see if the symbol was already defined by
1165 some other object. If so, we want to use the existing
1166 definition, and we do not want to report a multiple symbol
1167 definition error; we do this by clobbering *PSEC to be
1168 bfd_und_section_ptr.
1170 We treat a common symbol as a definition if the symbol in the
1171 shared library is a function, since common symbols always
1172 represent variables; this can cause confusion in principle, but
1173 any such confusion would seem to indicate an erroneous program or
1174 shared library. We also permit a common symbol in a regular
1175 object to override a weak symbol in a shared object. */
1177 if (newdyn
1178 && newdef
1179 && (olddef
1180 || (h->root.type == bfd_link_hash_common
1181 && (newweak
1182 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1184 *override = TRUE;
1185 newdef = FALSE;
1186 newdyncommon = FALSE;
1188 *psec = sec = bfd_und_section_ptr;
1189 *size_change_ok = TRUE;
1191 /* If we get here when the old symbol is a common symbol, then
1192 we are explicitly letting it override a weak symbol or
1193 function in a dynamic object, and we don't want to warn about
1194 a type change. If the old symbol is a defined symbol, a type
1195 change warning may still be appropriate. */
1197 if (h->root.type == bfd_link_hash_common)
1198 *type_change_ok = TRUE;
1201 /* Handle the special case of an old common symbol merging with a
1202 new symbol which looks like a common symbol in a shared object.
1203 We change *PSEC and *PVALUE to make the new symbol look like a
1204 common symbol, and let _bfd_generic_link_add_one_symbol do the
1205 right thing. */
1207 if (newdyncommon
1208 && h->root.type == bfd_link_hash_common)
1210 *override = TRUE;
1211 newdef = FALSE;
1212 newdyncommon = FALSE;
1213 *pvalue = sym->st_size;
1214 *psec = sec = bed->common_section (oldsec);
1215 *size_change_ok = TRUE;
1218 /* Skip weak definitions of symbols that are already defined. */
1219 if (newdef && olddef && newweak)
1220 *skip = TRUE;
1222 /* If the old symbol is from a dynamic object, and the new symbol is
1223 a definition which is not from a dynamic object, then the new
1224 symbol overrides the old symbol. Symbols from regular files
1225 always take precedence over symbols from dynamic objects, even if
1226 they are defined after the dynamic object in the link.
1228 As above, we again permit a common symbol in a regular object to
1229 override a definition in a shared object if the shared object
1230 symbol is a function or is weak. */
1232 flip = NULL;
1233 if (!newdyn
1234 && (newdef
1235 || (bfd_is_com_section (sec)
1236 && (oldweak
1237 || h->type == STT_FUNC)))
1238 && olddyn
1239 && olddef
1240 && h->def_dynamic)
1242 /* Change the hash table entry to undefined, and let
1243 _bfd_generic_link_add_one_symbol do the right thing with the
1244 new definition. */
1246 h->root.type = bfd_link_hash_undefined;
1247 h->root.u.undef.abfd = h->root.u.def.section->owner;
1248 *size_change_ok = TRUE;
1250 olddef = FALSE;
1251 olddyncommon = FALSE;
1253 /* We again permit a type change when a common symbol may be
1254 overriding a function. */
1256 if (bfd_is_com_section (sec))
1257 *type_change_ok = TRUE;
1259 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1260 flip = *sym_hash;
1261 else
1262 /* This union may have been set to be non-NULL when this symbol
1263 was seen in a dynamic object. We must force the union to be
1264 NULL, so that it is correct for a regular symbol. */
1265 h->verinfo.vertree = NULL;
1268 /* Handle the special case of a new common symbol merging with an
1269 old symbol that looks like it might be a common symbol defined in
1270 a shared object. Note that we have already handled the case in
1271 which a new common symbol should simply override the definition
1272 in the shared library. */
1274 if (! newdyn
1275 && bfd_is_com_section (sec)
1276 && olddyncommon)
1278 /* It would be best if we could set the hash table entry to a
1279 common symbol, but we don't know what to use for the section
1280 or the alignment. */
1281 if (! ((*info->callbacks->multiple_common)
1282 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1283 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1284 return FALSE;
1286 /* If the presumed common symbol in the dynamic object is
1287 larger, pretend that the new symbol has its size. */
1289 if (h->size > *pvalue)
1290 *pvalue = h->size;
1292 /* We need to remember the alignment required by the symbol
1293 in the dynamic object. */
1294 BFD_ASSERT (pold_alignment);
1295 *pold_alignment = h->root.u.def.section->alignment_power;
1297 olddef = FALSE;
1298 olddyncommon = FALSE;
1300 h->root.type = bfd_link_hash_undefined;
1301 h->root.u.undef.abfd = h->root.u.def.section->owner;
1303 *size_change_ok = TRUE;
1304 *type_change_ok = TRUE;
1306 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1307 flip = *sym_hash;
1308 else
1309 h->verinfo.vertree = NULL;
1312 if (flip != NULL)
1314 /* Handle the case where we had a versioned symbol in a dynamic
1315 library and now find a definition in a normal object. In this
1316 case, we make the versioned symbol point to the normal one. */
1317 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1318 flip->root.type = h->root.type;
1319 h->root.type = bfd_link_hash_indirect;
1320 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1321 (*bed->elf_backend_copy_indirect_symbol) (bed, flip, h);
1322 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1323 if (h->def_dynamic)
1325 h->def_dynamic = 0;
1326 flip->ref_dynamic = 1;
1330 return TRUE;
1333 /* This function is called to create an indirect symbol from the
1334 default for the symbol with the default version if needed. The
1335 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1336 set DYNSYM if the new indirect symbol is dynamic. */
1338 bfd_boolean
1339 _bfd_elf_add_default_symbol (bfd *abfd,
1340 struct bfd_link_info *info,
1341 struct elf_link_hash_entry *h,
1342 const char *name,
1343 Elf_Internal_Sym *sym,
1344 asection **psec,
1345 bfd_vma *value,
1346 bfd_boolean *dynsym,
1347 bfd_boolean override)
1349 bfd_boolean type_change_ok;
1350 bfd_boolean size_change_ok;
1351 bfd_boolean skip;
1352 char *shortname;
1353 struct elf_link_hash_entry *hi;
1354 struct bfd_link_hash_entry *bh;
1355 const struct elf_backend_data *bed;
1356 bfd_boolean collect;
1357 bfd_boolean dynamic;
1358 char *p;
1359 size_t len, shortlen;
1360 asection *sec;
1362 /* If this symbol has a version, and it is the default version, we
1363 create an indirect symbol from the default name to the fully
1364 decorated name. This will cause external references which do not
1365 specify a version to be bound to this version of the symbol. */
1366 p = strchr (name, ELF_VER_CHR);
1367 if (p == NULL || p[1] != ELF_VER_CHR)
1368 return TRUE;
1370 if (override)
1372 /* We are overridden by an old definition. We need to check if we
1373 need to create the indirect symbol from the default name. */
1374 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1375 FALSE, FALSE);
1376 BFD_ASSERT (hi != NULL);
1377 if (hi == h)
1378 return TRUE;
1379 while (hi->root.type == bfd_link_hash_indirect
1380 || hi->root.type == bfd_link_hash_warning)
1382 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1383 if (hi == h)
1384 return TRUE;
1388 bed = get_elf_backend_data (abfd);
1389 collect = bed->collect;
1390 dynamic = (abfd->flags & DYNAMIC) != 0;
1392 shortlen = p - name;
1393 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1394 if (shortname == NULL)
1395 return FALSE;
1396 memcpy (shortname, name, shortlen);
1397 shortname[shortlen] = '\0';
1399 /* We are going to create a new symbol. Merge it with any existing
1400 symbol with this name. For the purposes of the merge, act as
1401 though we were defining the symbol we just defined, although we
1402 actually going to define an indirect symbol. */
1403 type_change_ok = FALSE;
1404 size_change_ok = FALSE;
1405 sec = *psec;
1406 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1407 NULL, &hi, &skip, &override,
1408 &type_change_ok, &size_change_ok))
1409 return FALSE;
1411 if (skip)
1412 goto nondefault;
1414 if (! override)
1416 bh = &hi->root;
1417 if (! (_bfd_generic_link_add_one_symbol
1418 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1419 0, name, FALSE, collect, &bh)))
1420 return FALSE;
1421 hi = (struct elf_link_hash_entry *) bh;
1423 else
1425 /* In this case the symbol named SHORTNAME is overriding the
1426 indirect symbol we want to add. We were planning on making
1427 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1428 is the name without a version. NAME is the fully versioned
1429 name, and it is the default version.
1431 Overriding means that we already saw a definition for the
1432 symbol SHORTNAME in a regular object, and it is overriding
1433 the symbol defined in the dynamic object.
1435 When this happens, we actually want to change NAME, the
1436 symbol we just added, to refer to SHORTNAME. This will cause
1437 references to NAME in the shared object to become references
1438 to SHORTNAME in the regular object. This is what we expect
1439 when we override a function in a shared object: that the
1440 references in the shared object will be mapped to the
1441 definition in the regular object. */
1443 while (hi->root.type == bfd_link_hash_indirect
1444 || hi->root.type == bfd_link_hash_warning)
1445 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1447 h->root.type = bfd_link_hash_indirect;
1448 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1449 if (h->def_dynamic)
1451 h->def_dynamic = 0;
1452 hi->ref_dynamic = 1;
1453 if (hi->ref_regular
1454 || hi->def_regular)
1456 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1457 return FALSE;
1461 /* Now set HI to H, so that the following code will set the
1462 other fields correctly. */
1463 hi = h;
1466 /* If there is a duplicate definition somewhere, then HI may not
1467 point to an indirect symbol. We will have reported an error to
1468 the user in that case. */
1470 if (hi->root.type == bfd_link_hash_indirect)
1472 struct elf_link_hash_entry *ht;
1474 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1475 (*bed->elf_backend_copy_indirect_symbol) (bed, ht, hi);
1477 /* See if the new flags lead us to realize that the symbol must
1478 be dynamic. */
1479 if (! *dynsym)
1481 if (! dynamic)
1483 if (info->shared
1484 || hi->ref_dynamic)
1485 *dynsym = TRUE;
1487 else
1489 if (hi->ref_regular)
1490 *dynsym = TRUE;
1495 /* We also need to define an indirection from the nondefault version
1496 of the symbol. */
1498 nondefault:
1499 len = strlen (name);
1500 shortname = bfd_hash_allocate (&info->hash->table, len);
1501 if (shortname == NULL)
1502 return FALSE;
1503 memcpy (shortname, name, shortlen);
1504 memcpy (shortname + shortlen, p + 1, len - shortlen);
1506 /* Once again, merge with any existing symbol. */
1507 type_change_ok = FALSE;
1508 size_change_ok = FALSE;
1509 sec = *psec;
1510 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1511 NULL, &hi, &skip, &override,
1512 &type_change_ok, &size_change_ok))
1513 return FALSE;
1515 if (skip)
1516 return TRUE;
1518 if (override)
1520 /* Here SHORTNAME is a versioned name, so we don't expect to see
1521 the type of override we do in the case above unless it is
1522 overridden by a versioned definition. */
1523 if (hi->root.type != bfd_link_hash_defined
1524 && hi->root.type != bfd_link_hash_defweak)
1525 (*_bfd_error_handler)
1526 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1527 abfd, shortname);
1529 else
1531 bh = &hi->root;
1532 if (! (_bfd_generic_link_add_one_symbol
1533 (info, abfd, shortname, BSF_INDIRECT,
1534 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1535 return FALSE;
1536 hi = (struct elf_link_hash_entry *) bh;
1538 /* If there is a duplicate definition somewhere, then HI may not
1539 point to an indirect symbol. We will have reported an error
1540 to the user in that case. */
1542 if (hi->root.type == bfd_link_hash_indirect)
1544 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
1546 /* See if the new flags lead us to realize that the symbol
1547 must be dynamic. */
1548 if (! *dynsym)
1550 if (! dynamic)
1552 if (info->shared
1553 || hi->ref_dynamic)
1554 *dynsym = TRUE;
1556 else
1558 if (hi->ref_regular)
1559 *dynsym = TRUE;
1565 return TRUE;
1568 /* This routine is used to export all defined symbols into the dynamic
1569 symbol table. It is called via elf_link_hash_traverse. */
1571 bfd_boolean
1572 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1574 struct elf_info_failed *eif = data;
1576 /* Ignore indirect symbols. These are added by the versioning code. */
1577 if (h->root.type == bfd_link_hash_indirect)
1578 return TRUE;
1580 if (h->root.type == bfd_link_hash_warning)
1581 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1583 if (h->dynindx == -1
1584 && (h->def_regular
1585 || h->ref_regular))
1587 struct bfd_elf_version_tree *t;
1588 struct bfd_elf_version_expr *d;
1590 for (t = eif->verdefs; t != NULL; t = t->next)
1592 if (t->globals.list != NULL)
1594 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1595 if (d != NULL)
1596 goto doit;
1599 if (t->locals.list != NULL)
1601 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1602 if (d != NULL)
1603 return TRUE;
1607 if (!eif->verdefs)
1609 doit:
1610 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1612 eif->failed = TRUE;
1613 return FALSE;
1618 return TRUE;
1621 /* Look through the symbols which are defined in other shared
1622 libraries and referenced here. Update the list of version
1623 dependencies. This will be put into the .gnu.version_r section.
1624 This function is called via elf_link_hash_traverse. */
1626 bfd_boolean
1627 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1628 void *data)
1630 struct elf_find_verdep_info *rinfo = data;
1631 Elf_Internal_Verneed *t;
1632 Elf_Internal_Vernaux *a;
1633 bfd_size_type amt;
1635 if (h->root.type == bfd_link_hash_warning)
1636 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1638 /* We only care about symbols defined in shared objects with version
1639 information. */
1640 if (!h->def_dynamic
1641 || h->def_regular
1642 || h->dynindx == -1
1643 || h->verinfo.verdef == NULL)
1644 return TRUE;
1646 /* See if we already know about this version. */
1647 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1649 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1650 continue;
1652 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1653 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1654 return TRUE;
1656 break;
1659 /* This is a new version. Add it to tree we are building. */
1661 if (t == NULL)
1663 amt = sizeof *t;
1664 t = bfd_zalloc (rinfo->output_bfd, amt);
1665 if (t == NULL)
1667 rinfo->failed = TRUE;
1668 return FALSE;
1671 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1672 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1673 elf_tdata (rinfo->output_bfd)->verref = t;
1676 amt = sizeof *a;
1677 a = bfd_zalloc (rinfo->output_bfd, amt);
1679 /* Note that we are copying a string pointer here, and testing it
1680 above. If bfd_elf_string_from_elf_section is ever changed to
1681 discard the string data when low in memory, this will have to be
1682 fixed. */
1683 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1685 a->vna_flags = h->verinfo.verdef->vd_flags;
1686 a->vna_nextptr = t->vn_auxptr;
1688 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1689 ++rinfo->vers;
1691 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1693 t->vn_auxptr = a;
1695 return TRUE;
1698 /* Figure out appropriate versions for all the symbols. We may not
1699 have the version number script until we have read all of the input
1700 files, so until that point we don't know which symbols should be
1701 local. This function is called via elf_link_hash_traverse. */
1703 bfd_boolean
1704 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1706 struct elf_assign_sym_version_info *sinfo;
1707 struct bfd_link_info *info;
1708 const struct elf_backend_data *bed;
1709 struct elf_info_failed eif;
1710 char *p;
1711 bfd_size_type amt;
1713 sinfo = data;
1714 info = sinfo->info;
1716 if (h->root.type == bfd_link_hash_warning)
1717 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1719 /* Fix the symbol flags. */
1720 eif.failed = FALSE;
1721 eif.info = info;
1722 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1724 if (eif.failed)
1725 sinfo->failed = TRUE;
1726 return FALSE;
1729 /* We only need version numbers for symbols defined in regular
1730 objects. */
1731 if (!h->def_regular)
1732 return TRUE;
1734 bed = get_elf_backend_data (sinfo->output_bfd);
1735 p = strchr (h->root.root.string, ELF_VER_CHR);
1736 if (p != NULL && h->verinfo.vertree == NULL)
1738 struct bfd_elf_version_tree *t;
1739 bfd_boolean hidden;
1741 hidden = TRUE;
1743 /* There are two consecutive ELF_VER_CHR characters if this is
1744 not a hidden symbol. */
1745 ++p;
1746 if (*p == ELF_VER_CHR)
1748 hidden = FALSE;
1749 ++p;
1752 /* If there is no version string, we can just return out. */
1753 if (*p == '\0')
1755 if (hidden)
1756 h->hidden = 1;
1757 return TRUE;
1760 /* Look for the version. If we find it, it is no longer weak. */
1761 for (t = sinfo->verdefs; t != NULL; t = t->next)
1763 if (strcmp (t->name, p) == 0)
1765 size_t len;
1766 char *alc;
1767 struct bfd_elf_version_expr *d;
1769 len = p - h->root.root.string;
1770 alc = bfd_malloc (len);
1771 if (alc == NULL)
1772 return FALSE;
1773 memcpy (alc, h->root.root.string, len - 1);
1774 alc[len - 1] = '\0';
1775 if (alc[len - 2] == ELF_VER_CHR)
1776 alc[len - 2] = '\0';
1778 h->verinfo.vertree = t;
1779 t->used = TRUE;
1780 d = NULL;
1782 if (t->globals.list != NULL)
1783 d = (*t->match) (&t->globals, NULL, alc);
1785 /* See if there is anything to force this symbol to
1786 local scope. */
1787 if (d == NULL && t->locals.list != NULL)
1789 d = (*t->match) (&t->locals, NULL, alc);
1790 if (d != NULL
1791 && h->dynindx != -1
1792 && ! info->export_dynamic)
1793 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1796 free (alc);
1797 break;
1801 /* If we are building an application, we need to create a
1802 version node for this version. */
1803 if (t == NULL && info->executable)
1805 struct bfd_elf_version_tree **pp;
1806 int version_index;
1808 /* If we aren't going to export this symbol, we don't need
1809 to worry about it. */
1810 if (h->dynindx == -1)
1811 return TRUE;
1813 amt = sizeof *t;
1814 t = bfd_zalloc (sinfo->output_bfd, amt);
1815 if (t == NULL)
1817 sinfo->failed = TRUE;
1818 return FALSE;
1821 t->name = p;
1822 t->name_indx = (unsigned int) -1;
1823 t->used = TRUE;
1825 version_index = 1;
1826 /* Don't count anonymous version tag. */
1827 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1828 version_index = 0;
1829 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1830 ++version_index;
1831 t->vernum = version_index;
1833 *pp = t;
1835 h->verinfo.vertree = t;
1837 else if (t == NULL)
1839 /* We could not find the version for a symbol when
1840 generating a shared archive. Return an error. */
1841 (*_bfd_error_handler)
1842 (_("%B: undefined versioned symbol name %s"),
1843 sinfo->output_bfd, h->root.root.string);
1844 bfd_set_error (bfd_error_bad_value);
1845 sinfo->failed = TRUE;
1846 return FALSE;
1849 if (hidden)
1850 h->hidden = 1;
1853 /* If we don't have a version for this symbol, see if we can find
1854 something. */
1855 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1857 struct bfd_elf_version_tree *t;
1858 struct bfd_elf_version_tree *local_ver;
1859 struct bfd_elf_version_expr *d;
1861 /* See if can find what version this symbol is in. If the
1862 symbol is supposed to be local, then don't actually register
1863 it. */
1864 local_ver = NULL;
1865 for (t = sinfo->verdefs; t != NULL; t = t->next)
1867 if (t->globals.list != NULL)
1869 bfd_boolean matched;
1871 matched = FALSE;
1872 d = NULL;
1873 while ((d = (*t->match) (&t->globals, d,
1874 h->root.root.string)) != NULL)
1875 if (d->symver)
1876 matched = TRUE;
1877 else
1879 /* There is a version without definition. Make
1880 the symbol the default definition for this
1881 version. */
1882 h->verinfo.vertree = t;
1883 local_ver = NULL;
1884 d->script = 1;
1885 break;
1887 if (d != NULL)
1888 break;
1889 else if (matched)
1890 /* There is no undefined version for this symbol. Hide the
1891 default one. */
1892 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1895 if (t->locals.list != NULL)
1897 d = NULL;
1898 while ((d = (*t->match) (&t->locals, d,
1899 h->root.root.string)) != NULL)
1901 local_ver = t;
1902 /* If the match is "*", keep looking for a more
1903 explicit, perhaps even global, match.
1904 XXX: Shouldn't this be !d->wildcard instead? */
1905 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1906 break;
1909 if (d != NULL)
1910 break;
1914 if (local_ver != NULL)
1916 h->verinfo.vertree = local_ver;
1917 if (h->dynindx != -1
1918 && ! info->export_dynamic)
1920 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1925 return TRUE;
1928 /* Read and swap the relocs from the section indicated by SHDR. This
1929 may be either a REL or a RELA section. The relocations are
1930 translated into RELA relocations and stored in INTERNAL_RELOCS,
1931 which should have already been allocated to contain enough space.
1932 The EXTERNAL_RELOCS are a buffer where the external form of the
1933 relocations should be stored.
1935 Returns FALSE if something goes wrong. */
1937 static bfd_boolean
1938 elf_link_read_relocs_from_section (bfd *abfd,
1939 asection *sec,
1940 Elf_Internal_Shdr *shdr,
1941 void *external_relocs,
1942 Elf_Internal_Rela *internal_relocs)
1944 const struct elf_backend_data *bed;
1945 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1946 const bfd_byte *erela;
1947 const bfd_byte *erelaend;
1948 Elf_Internal_Rela *irela;
1949 Elf_Internal_Shdr *symtab_hdr;
1950 size_t nsyms;
1952 /* Position ourselves at the start of the section. */
1953 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1954 return FALSE;
1956 /* Read the relocations. */
1957 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1958 return FALSE;
1960 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1961 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1963 bed = get_elf_backend_data (abfd);
1965 /* Convert the external relocations to the internal format. */
1966 if (shdr->sh_entsize == bed->s->sizeof_rel)
1967 swap_in = bed->s->swap_reloc_in;
1968 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1969 swap_in = bed->s->swap_reloca_in;
1970 else
1972 bfd_set_error (bfd_error_wrong_format);
1973 return FALSE;
1976 erela = external_relocs;
1977 erelaend = erela + shdr->sh_size;
1978 irela = internal_relocs;
1979 while (erela < erelaend)
1981 bfd_vma r_symndx;
1983 (*swap_in) (abfd, erela, irela);
1984 r_symndx = ELF32_R_SYM (irela->r_info);
1985 if (bed->s->arch_size == 64)
1986 r_symndx >>= 24;
1987 if ((size_t) r_symndx >= nsyms)
1989 (*_bfd_error_handler)
1990 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
1991 " for offset 0x%lx in section `%A'"),
1992 abfd, sec,
1993 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
1994 bfd_set_error (bfd_error_bad_value);
1995 return FALSE;
1997 irela += bed->s->int_rels_per_ext_rel;
1998 erela += shdr->sh_entsize;
2001 return TRUE;
2004 /* Read and swap the relocs for a section O. They may have been
2005 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2006 not NULL, they are used as buffers to read into. They are known to
2007 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2008 the return value is allocated using either malloc or bfd_alloc,
2009 according to the KEEP_MEMORY argument. If O has two relocation
2010 sections (both REL and RELA relocations), then the REL_HDR
2011 relocations will appear first in INTERNAL_RELOCS, followed by the
2012 REL_HDR2 relocations. */
2014 Elf_Internal_Rela *
2015 _bfd_elf_link_read_relocs (bfd *abfd,
2016 asection *o,
2017 void *external_relocs,
2018 Elf_Internal_Rela *internal_relocs,
2019 bfd_boolean keep_memory)
2021 Elf_Internal_Shdr *rel_hdr;
2022 void *alloc1 = NULL;
2023 Elf_Internal_Rela *alloc2 = NULL;
2024 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2026 if (elf_section_data (o)->relocs != NULL)
2027 return elf_section_data (o)->relocs;
2029 if (o->reloc_count == 0)
2030 return NULL;
2032 rel_hdr = &elf_section_data (o)->rel_hdr;
2034 if (internal_relocs == NULL)
2036 bfd_size_type size;
2038 size = o->reloc_count;
2039 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2040 if (keep_memory)
2041 internal_relocs = bfd_alloc (abfd, size);
2042 else
2043 internal_relocs = alloc2 = bfd_malloc (size);
2044 if (internal_relocs == NULL)
2045 goto error_return;
2048 if (external_relocs == NULL)
2050 bfd_size_type size = rel_hdr->sh_size;
2052 if (elf_section_data (o)->rel_hdr2)
2053 size += elf_section_data (o)->rel_hdr2->sh_size;
2054 alloc1 = bfd_malloc (size);
2055 if (alloc1 == NULL)
2056 goto error_return;
2057 external_relocs = alloc1;
2060 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2061 external_relocs,
2062 internal_relocs))
2063 goto error_return;
2064 if (elf_section_data (o)->rel_hdr2
2065 && (!elf_link_read_relocs_from_section
2066 (abfd, o,
2067 elf_section_data (o)->rel_hdr2,
2068 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2069 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2070 * bed->s->int_rels_per_ext_rel))))
2071 goto error_return;
2073 /* Cache the results for next time, if we can. */
2074 if (keep_memory)
2075 elf_section_data (o)->relocs = internal_relocs;
2077 if (alloc1 != NULL)
2078 free (alloc1);
2080 /* Don't free alloc2, since if it was allocated we are passing it
2081 back (under the name of internal_relocs). */
2083 return internal_relocs;
2085 error_return:
2086 if (alloc1 != NULL)
2087 free (alloc1);
2088 if (alloc2 != NULL)
2089 free (alloc2);
2090 return NULL;
2093 /* Compute the size of, and allocate space for, REL_HDR which is the
2094 section header for a section containing relocations for O. */
2096 bfd_boolean
2097 _bfd_elf_link_size_reloc_section (bfd *abfd,
2098 Elf_Internal_Shdr *rel_hdr,
2099 asection *o)
2101 bfd_size_type reloc_count;
2102 bfd_size_type num_rel_hashes;
2104 /* Figure out how many relocations there will be. */
2105 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2106 reloc_count = elf_section_data (o)->rel_count;
2107 else
2108 reloc_count = elf_section_data (o)->rel_count2;
2110 num_rel_hashes = o->reloc_count;
2111 if (num_rel_hashes < reloc_count)
2112 num_rel_hashes = reloc_count;
2114 /* That allows us to calculate the size of the section. */
2115 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2117 /* The contents field must last into write_object_contents, so we
2118 allocate it with bfd_alloc rather than malloc. Also since we
2119 cannot be sure that the contents will actually be filled in,
2120 we zero the allocated space. */
2121 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2122 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2123 return FALSE;
2125 /* We only allocate one set of hash entries, so we only do it the
2126 first time we are called. */
2127 if (elf_section_data (o)->rel_hashes == NULL
2128 && num_rel_hashes)
2130 struct elf_link_hash_entry **p;
2132 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2133 if (p == NULL)
2134 return FALSE;
2136 elf_section_data (o)->rel_hashes = p;
2139 return TRUE;
2142 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2143 originated from the section given by INPUT_REL_HDR) to the
2144 OUTPUT_BFD. */
2146 bfd_boolean
2147 _bfd_elf_link_output_relocs (bfd *output_bfd,
2148 asection *input_section,
2149 Elf_Internal_Shdr *input_rel_hdr,
2150 Elf_Internal_Rela *internal_relocs,
2151 struct elf_link_hash_entry **rel_hash
2152 ATTRIBUTE_UNUSED)
2154 Elf_Internal_Rela *irela;
2155 Elf_Internal_Rela *irelaend;
2156 bfd_byte *erel;
2157 Elf_Internal_Shdr *output_rel_hdr;
2158 asection *output_section;
2159 unsigned int *rel_countp = NULL;
2160 const struct elf_backend_data *bed;
2161 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2163 output_section = input_section->output_section;
2164 output_rel_hdr = NULL;
2166 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2167 == input_rel_hdr->sh_entsize)
2169 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2170 rel_countp = &elf_section_data (output_section)->rel_count;
2172 else if (elf_section_data (output_section)->rel_hdr2
2173 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2174 == input_rel_hdr->sh_entsize))
2176 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2177 rel_countp = &elf_section_data (output_section)->rel_count2;
2179 else
2181 (*_bfd_error_handler)
2182 (_("%B: relocation size mismatch in %B section %A"),
2183 output_bfd, input_section->owner, input_section);
2184 bfd_set_error (bfd_error_wrong_object_format);
2185 return FALSE;
2188 bed = get_elf_backend_data (output_bfd);
2189 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2190 swap_out = bed->s->swap_reloc_out;
2191 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2192 swap_out = bed->s->swap_reloca_out;
2193 else
2194 abort ();
2196 erel = output_rel_hdr->contents;
2197 erel += *rel_countp * input_rel_hdr->sh_entsize;
2198 irela = internal_relocs;
2199 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2200 * bed->s->int_rels_per_ext_rel);
2201 while (irela < irelaend)
2203 (*swap_out) (output_bfd, irela, erel);
2204 irela += bed->s->int_rels_per_ext_rel;
2205 erel += input_rel_hdr->sh_entsize;
2208 /* Bump the counter, so that we know where to add the next set of
2209 relocations. */
2210 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2212 return TRUE;
2215 /* Fix up the flags for a symbol. This handles various cases which
2216 can only be fixed after all the input files are seen. This is
2217 currently called by both adjust_dynamic_symbol and
2218 assign_sym_version, which is unnecessary but perhaps more robust in
2219 the face of future changes. */
2221 bfd_boolean
2222 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2223 struct elf_info_failed *eif)
2225 /* If this symbol was mentioned in a non-ELF file, try to set
2226 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2227 permit a non-ELF file to correctly refer to a symbol defined in
2228 an ELF dynamic object. */
2229 if (h->non_elf)
2231 while (h->root.type == bfd_link_hash_indirect)
2232 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2234 if (h->root.type != bfd_link_hash_defined
2235 && h->root.type != bfd_link_hash_defweak)
2237 h->ref_regular = 1;
2238 h->ref_regular_nonweak = 1;
2240 else
2242 if (h->root.u.def.section->owner != NULL
2243 && (bfd_get_flavour (h->root.u.def.section->owner)
2244 == bfd_target_elf_flavour))
2246 h->ref_regular = 1;
2247 h->ref_regular_nonweak = 1;
2249 else
2250 h->def_regular = 1;
2253 if (h->dynindx == -1
2254 && (h->def_dynamic
2255 || h->ref_dynamic))
2257 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2259 eif->failed = TRUE;
2260 return FALSE;
2264 else
2266 /* Unfortunately, NON_ELF is only correct if the symbol
2267 was first seen in a non-ELF file. Fortunately, if the symbol
2268 was first seen in an ELF file, we're probably OK unless the
2269 symbol was defined in a non-ELF file. Catch that case here.
2270 FIXME: We're still in trouble if the symbol was first seen in
2271 a dynamic object, and then later in a non-ELF regular object. */
2272 if ((h->root.type == bfd_link_hash_defined
2273 || h->root.type == bfd_link_hash_defweak)
2274 && !h->def_regular
2275 && (h->root.u.def.section->owner != NULL
2276 ? (bfd_get_flavour (h->root.u.def.section->owner)
2277 != bfd_target_elf_flavour)
2278 : (bfd_is_abs_section (h->root.u.def.section)
2279 && !h->def_dynamic)))
2280 h->def_regular = 1;
2283 /* If this is a final link, and the symbol was defined as a common
2284 symbol in a regular object file, and there was no definition in
2285 any dynamic object, then the linker will have allocated space for
2286 the symbol in a common section but the DEF_REGULAR
2287 flag will not have been set. */
2288 if (h->root.type == bfd_link_hash_defined
2289 && !h->def_regular
2290 && h->ref_regular
2291 && !h->def_dynamic
2292 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2293 h->def_regular = 1;
2295 /* If -Bsymbolic was used (which means to bind references to global
2296 symbols to the definition within the shared object), and this
2297 symbol was defined in a regular object, then it actually doesn't
2298 need a PLT entry. Likewise, if the symbol has non-default
2299 visibility. If the symbol has hidden or internal visibility, we
2300 will force it local. */
2301 if (h->needs_plt
2302 && eif->info->shared
2303 && is_elf_hash_table (eif->info->hash)
2304 && (eif->info->symbolic
2305 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2306 && h->def_regular)
2308 const struct elf_backend_data *bed;
2309 bfd_boolean force_local;
2311 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2313 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2314 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2315 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2318 /* If a weak undefined symbol has non-default visibility, we also
2319 hide it from the dynamic linker. */
2320 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2321 && h->root.type == bfd_link_hash_undefweak)
2323 const struct elf_backend_data *bed;
2324 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2325 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2328 /* If this is a weak defined symbol in a dynamic object, and we know
2329 the real definition in the dynamic object, copy interesting flags
2330 over to the real definition. */
2331 if (h->u.weakdef != NULL)
2333 struct elf_link_hash_entry *weakdef;
2335 weakdef = h->u.weakdef;
2336 if (h->root.type == bfd_link_hash_indirect)
2337 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2339 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2340 || h->root.type == bfd_link_hash_defweak);
2341 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2342 || weakdef->root.type == bfd_link_hash_defweak);
2343 BFD_ASSERT (weakdef->def_dynamic);
2345 /* If the real definition is defined by a regular object file,
2346 don't do anything special. See the longer description in
2347 _bfd_elf_adjust_dynamic_symbol, below. */
2348 if (weakdef->def_regular)
2349 h->u.weakdef = NULL;
2350 else
2352 const struct elf_backend_data *bed;
2354 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2355 (*bed->elf_backend_copy_indirect_symbol) (bed, weakdef, h);
2359 return TRUE;
2362 /* Make the backend pick a good value for a dynamic symbol. This is
2363 called via elf_link_hash_traverse, and also calls itself
2364 recursively. */
2366 bfd_boolean
2367 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2369 struct elf_info_failed *eif = data;
2370 bfd *dynobj;
2371 const struct elf_backend_data *bed;
2373 if (! is_elf_hash_table (eif->info->hash))
2374 return FALSE;
2376 if (h->root.type == bfd_link_hash_warning)
2378 h->got = elf_hash_table (eif->info)->init_got_offset;
2379 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2381 /* When warning symbols are created, they **replace** the "real"
2382 entry in the hash table, thus we never get to see the real
2383 symbol in a hash traversal. So look at it now. */
2384 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2387 /* Ignore indirect symbols. These are added by the versioning code. */
2388 if (h->root.type == bfd_link_hash_indirect)
2389 return TRUE;
2391 /* Fix the symbol flags. */
2392 if (! _bfd_elf_fix_symbol_flags (h, eif))
2393 return FALSE;
2395 /* If this symbol does not require a PLT entry, and it is not
2396 defined by a dynamic object, or is not referenced by a regular
2397 object, ignore it. We do have to handle a weak defined symbol,
2398 even if no regular object refers to it, if we decided to add it
2399 to the dynamic symbol table. FIXME: Do we normally need to worry
2400 about symbols which are defined by one dynamic object and
2401 referenced by another one? */
2402 if (!h->needs_plt
2403 && (h->def_regular
2404 || !h->def_dynamic
2405 || (!h->ref_regular
2406 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2408 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2409 return TRUE;
2412 /* If we've already adjusted this symbol, don't do it again. This
2413 can happen via a recursive call. */
2414 if (h->dynamic_adjusted)
2415 return TRUE;
2417 /* Don't look at this symbol again. Note that we must set this
2418 after checking the above conditions, because we may look at a
2419 symbol once, decide not to do anything, and then get called
2420 recursively later after REF_REGULAR is set below. */
2421 h->dynamic_adjusted = 1;
2423 /* If this is a weak definition, and we know a real definition, and
2424 the real symbol is not itself defined by a regular object file,
2425 then get a good value for the real definition. We handle the
2426 real symbol first, for the convenience of the backend routine.
2428 Note that there is a confusing case here. If the real definition
2429 is defined by a regular object file, we don't get the real symbol
2430 from the dynamic object, but we do get the weak symbol. If the
2431 processor backend uses a COPY reloc, then if some routine in the
2432 dynamic object changes the real symbol, we will not see that
2433 change in the corresponding weak symbol. This is the way other
2434 ELF linkers work as well, and seems to be a result of the shared
2435 library model.
2437 I will clarify this issue. Most SVR4 shared libraries define the
2438 variable _timezone and define timezone as a weak synonym. The
2439 tzset call changes _timezone. If you write
2440 extern int timezone;
2441 int _timezone = 5;
2442 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2443 you might expect that, since timezone is a synonym for _timezone,
2444 the same number will print both times. However, if the processor
2445 backend uses a COPY reloc, then actually timezone will be copied
2446 into your process image, and, since you define _timezone
2447 yourself, _timezone will not. Thus timezone and _timezone will
2448 wind up at different memory locations. The tzset call will set
2449 _timezone, leaving timezone unchanged. */
2451 if (h->u.weakdef != NULL)
2453 /* If we get to this point, we know there is an implicit
2454 reference by a regular object file via the weak symbol H.
2455 FIXME: Is this really true? What if the traversal finds
2456 H->U.WEAKDEF before it finds H? */
2457 h->u.weakdef->ref_regular = 1;
2459 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2460 return FALSE;
2463 /* If a symbol has no type and no size and does not require a PLT
2464 entry, then we are probably about to do the wrong thing here: we
2465 are probably going to create a COPY reloc for an empty object.
2466 This case can arise when a shared object is built with assembly
2467 code, and the assembly code fails to set the symbol type. */
2468 if (h->size == 0
2469 && h->type == STT_NOTYPE
2470 && !h->needs_plt)
2471 (*_bfd_error_handler)
2472 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2473 h->root.root.string);
2475 dynobj = elf_hash_table (eif->info)->dynobj;
2476 bed = get_elf_backend_data (dynobj);
2477 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2479 eif->failed = TRUE;
2480 return FALSE;
2483 return TRUE;
2486 /* Adjust all external symbols pointing into SEC_MERGE sections
2487 to reflect the object merging within the sections. */
2489 bfd_boolean
2490 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2492 asection *sec;
2494 if (h->root.type == bfd_link_hash_warning)
2495 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2497 if ((h->root.type == bfd_link_hash_defined
2498 || h->root.type == bfd_link_hash_defweak)
2499 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2500 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2502 bfd *output_bfd = data;
2504 h->root.u.def.value =
2505 _bfd_merged_section_offset (output_bfd,
2506 &h->root.u.def.section,
2507 elf_section_data (sec)->sec_info,
2508 h->root.u.def.value);
2511 return TRUE;
2514 /* Returns false if the symbol referred to by H should be considered
2515 to resolve local to the current module, and true if it should be
2516 considered to bind dynamically. */
2518 bfd_boolean
2519 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2520 struct bfd_link_info *info,
2521 bfd_boolean ignore_protected)
2523 bfd_boolean binding_stays_local_p;
2525 if (h == NULL)
2526 return FALSE;
2528 while (h->root.type == bfd_link_hash_indirect
2529 || h->root.type == bfd_link_hash_warning)
2530 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2532 /* If it was forced local, then clearly it's not dynamic. */
2533 if (h->dynindx == -1)
2534 return FALSE;
2535 if (h->forced_local)
2536 return FALSE;
2538 /* Identify the cases where name binding rules say that a
2539 visible symbol resolves locally. */
2540 binding_stays_local_p = info->executable || info->symbolic;
2542 switch (ELF_ST_VISIBILITY (h->other))
2544 case STV_INTERNAL:
2545 case STV_HIDDEN:
2546 return FALSE;
2548 case STV_PROTECTED:
2549 /* Proper resolution for function pointer equality may require
2550 that these symbols perhaps be resolved dynamically, even though
2551 we should be resolving them to the current module. */
2552 if (!ignore_protected || h->type != STT_FUNC)
2553 binding_stays_local_p = TRUE;
2554 break;
2556 default:
2557 break;
2560 /* If it isn't defined locally, then clearly it's dynamic. */
2561 if (!h->def_regular)
2562 return TRUE;
2564 /* Otherwise, the symbol is dynamic if binding rules don't tell
2565 us that it remains local. */
2566 return !binding_stays_local_p;
2569 /* Return true if the symbol referred to by H should be considered
2570 to resolve local to the current module, and false otherwise. Differs
2571 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2572 undefined symbols and weak symbols. */
2574 bfd_boolean
2575 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2576 struct bfd_link_info *info,
2577 bfd_boolean local_protected)
2579 /* If it's a local sym, of course we resolve locally. */
2580 if (h == NULL)
2581 return TRUE;
2583 /* Common symbols that become definitions don't get the DEF_REGULAR
2584 flag set, so test it first, and don't bail out. */
2585 if (ELF_COMMON_DEF_P (h))
2586 /* Do nothing. */;
2587 /* If we don't have a definition in a regular file, then we can't
2588 resolve locally. The sym is either undefined or dynamic. */
2589 else if (!h->def_regular)
2590 return FALSE;
2592 /* Forced local symbols resolve locally. */
2593 if (h->forced_local)
2594 return TRUE;
2596 /* As do non-dynamic symbols. */
2597 if (h->dynindx == -1)
2598 return TRUE;
2600 /* At this point, we know the symbol is defined and dynamic. In an
2601 executable it must resolve locally, likewise when building symbolic
2602 shared libraries. */
2603 if (info->executable || info->symbolic)
2604 return TRUE;
2606 /* Now deal with defined dynamic symbols in shared libraries. Ones
2607 with default visibility might not resolve locally. */
2608 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2609 return FALSE;
2611 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2612 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2613 return TRUE;
2615 /* STV_PROTECTED non-function symbols are local. */
2616 if (h->type != STT_FUNC)
2617 return TRUE;
2619 /* Function pointer equality tests may require that STV_PROTECTED
2620 symbols be treated as dynamic symbols, even when we know that the
2621 dynamic linker will resolve them locally. */
2622 return local_protected;
2625 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2626 aligned. Returns the first TLS output section. */
2628 struct bfd_section *
2629 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2631 struct bfd_section *sec, *tls;
2632 unsigned int align = 0;
2634 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2635 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2636 break;
2637 tls = sec;
2639 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2640 if (sec->alignment_power > align)
2641 align = sec->alignment_power;
2643 elf_hash_table (info)->tls_sec = tls;
2645 /* Ensure the alignment of the first section is the largest alignment,
2646 so that the tls segment starts aligned. */
2647 if (tls != NULL)
2648 tls->alignment_power = align;
2650 return tls;
2653 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2654 static bfd_boolean
2655 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2656 Elf_Internal_Sym *sym)
2658 const struct elf_backend_data *bed;
2660 /* Local symbols do not count, but target specific ones might. */
2661 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2662 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2663 return FALSE;
2665 /* Function symbols do not count. */
2666 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2667 return FALSE;
2669 /* If the section is undefined, then so is the symbol. */
2670 if (sym->st_shndx == SHN_UNDEF)
2671 return FALSE;
2673 /* If the symbol is defined in the common section, then
2674 it is a common definition and so does not count. */
2675 bed = get_elf_backend_data (abfd);
2676 if (bed->common_definition (sym))
2677 return FALSE;
2679 /* If the symbol is in a target specific section then we
2680 must rely upon the backend to tell us what it is. */
2681 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2682 /* FIXME - this function is not coded yet:
2684 return _bfd_is_global_symbol_definition (abfd, sym);
2686 Instead for now assume that the definition is not global,
2687 Even if this is wrong, at least the linker will behave
2688 in the same way that it used to do. */
2689 return FALSE;
2691 return TRUE;
2694 /* Search the symbol table of the archive element of the archive ABFD
2695 whose archive map contains a mention of SYMDEF, and determine if
2696 the symbol is defined in this element. */
2697 static bfd_boolean
2698 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2700 Elf_Internal_Shdr * hdr;
2701 bfd_size_type symcount;
2702 bfd_size_type extsymcount;
2703 bfd_size_type extsymoff;
2704 Elf_Internal_Sym *isymbuf;
2705 Elf_Internal_Sym *isym;
2706 Elf_Internal_Sym *isymend;
2707 bfd_boolean result;
2709 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2710 if (abfd == NULL)
2711 return FALSE;
2713 if (! bfd_check_format (abfd, bfd_object))
2714 return FALSE;
2716 /* If we have already included the element containing this symbol in the
2717 link then we do not need to include it again. Just claim that any symbol
2718 it contains is not a definition, so that our caller will not decide to
2719 (re)include this element. */
2720 if (abfd->archive_pass)
2721 return FALSE;
2723 /* Select the appropriate symbol table. */
2724 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2725 hdr = &elf_tdata (abfd)->symtab_hdr;
2726 else
2727 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2729 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2731 /* The sh_info field of the symtab header tells us where the
2732 external symbols start. We don't care about the local symbols. */
2733 if (elf_bad_symtab (abfd))
2735 extsymcount = symcount;
2736 extsymoff = 0;
2738 else
2740 extsymcount = symcount - hdr->sh_info;
2741 extsymoff = hdr->sh_info;
2744 if (extsymcount == 0)
2745 return FALSE;
2747 /* Read in the symbol table. */
2748 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2749 NULL, NULL, NULL);
2750 if (isymbuf == NULL)
2751 return FALSE;
2753 /* Scan the symbol table looking for SYMDEF. */
2754 result = FALSE;
2755 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2757 const char *name;
2759 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2760 isym->st_name);
2761 if (name == NULL)
2762 break;
2764 if (strcmp (name, symdef->name) == 0)
2766 result = is_global_data_symbol_definition (abfd, isym);
2767 break;
2771 free (isymbuf);
2773 return result;
2776 /* Add an entry to the .dynamic table. */
2778 bfd_boolean
2779 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2780 bfd_vma tag,
2781 bfd_vma val)
2783 struct elf_link_hash_table *hash_table;
2784 const struct elf_backend_data *bed;
2785 asection *s;
2786 bfd_size_type newsize;
2787 bfd_byte *newcontents;
2788 Elf_Internal_Dyn dyn;
2790 hash_table = elf_hash_table (info);
2791 if (! is_elf_hash_table (hash_table))
2792 return FALSE;
2794 if (info->warn_shared_textrel && info->shared && tag == DT_TEXTREL)
2795 _bfd_error_handler
2796 (_("warning: creating a DT_TEXTREL in a shared object."));
2798 bed = get_elf_backend_data (hash_table->dynobj);
2799 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2800 BFD_ASSERT (s != NULL);
2802 newsize = s->size + bed->s->sizeof_dyn;
2803 newcontents = bfd_realloc (s->contents, newsize);
2804 if (newcontents == NULL)
2805 return FALSE;
2807 dyn.d_tag = tag;
2808 dyn.d_un.d_val = val;
2809 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2811 s->size = newsize;
2812 s->contents = newcontents;
2814 return TRUE;
2817 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2818 otherwise just check whether one already exists. Returns -1 on error,
2819 1 if a DT_NEEDED tag already exists, and 0 on success. */
2821 static int
2822 elf_add_dt_needed_tag (bfd *abfd,
2823 struct bfd_link_info *info,
2824 const char *soname,
2825 bfd_boolean do_it)
2827 struct elf_link_hash_table *hash_table;
2828 bfd_size_type oldsize;
2829 bfd_size_type strindex;
2831 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2832 return -1;
2834 hash_table = elf_hash_table (info);
2835 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2836 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2837 if (strindex == (bfd_size_type) -1)
2838 return -1;
2840 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2842 asection *sdyn;
2843 const struct elf_backend_data *bed;
2844 bfd_byte *extdyn;
2846 bed = get_elf_backend_data (hash_table->dynobj);
2847 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2848 if (sdyn != NULL)
2849 for (extdyn = sdyn->contents;
2850 extdyn < sdyn->contents + sdyn->size;
2851 extdyn += bed->s->sizeof_dyn)
2853 Elf_Internal_Dyn dyn;
2855 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2856 if (dyn.d_tag == DT_NEEDED
2857 && dyn.d_un.d_val == strindex)
2859 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2860 return 1;
2865 if (do_it)
2867 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2868 return -1;
2870 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2871 return -1;
2873 else
2874 /* We were just checking for existence of the tag. */
2875 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2877 return 0;
2880 /* Called via elf_link_hash_traverse, elf_smash_syms sets all symbols
2881 belonging to NOT_NEEDED to bfd_link_hash_new. We know there are no
2882 references from regular objects to these symbols.
2884 ??? Should we do something about references from other dynamic
2885 obects? If not, we potentially lose some warnings about undefined
2886 symbols. But how can we recover the initial undefined / undefweak
2887 state? */
2889 struct elf_smash_syms_data
2891 bfd *not_needed;
2892 struct elf_link_hash_table *htab;
2893 bfd_boolean twiddled;
2896 static bfd_boolean
2897 elf_smash_syms (struct elf_link_hash_entry *h, void *data)
2899 struct elf_smash_syms_data *inf = (struct elf_smash_syms_data *) data;
2900 struct bfd_link_hash_entry *bh;
2902 switch (h->root.type)
2904 default:
2905 case bfd_link_hash_new:
2906 return TRUE;
2908 case bfd_link_hash_undefined:
2909 if (h->root.u.undef.abfd != inf->not_needed)
2910 return TRUE;
2911 if (h->root.u.undef.weak != NULL
2912 && h->root.u.undef.weak != inf->not_needed)
2914 /* Symbol was undefweak in u.undef.weak bfd, and has become
2915 undefined in as-needed lib. Restore weak. */
2916 h->root.type = bfd_link_hash_undefweak;
2917 h->root.u.undef.abfd = h->root.u.undef.weak;
2918 if (h->root.u.undef.next != NULL
2919 || inf->htab->root.undefs_tail == &h->root)
2920 inf->twiddled = TRUE;
2921 return TRUE;
2923 break;
2925 case bfd_link_hash_undefweak:
2926 if (h->root.u.undef.abfd != inf->not_needed)
2927 return TRUE;
2928 break;
2930 case bfd_link_hash_defined:
2931 case bfd_link_hash_defweak:
2932 if (h->root.u.def.section->owner != inf->not_needed)
2933 return TRUE;
2934 break;
2936 case bfd_link_hash_common:
2937 if (h->root.u.c.p->section->owner != inf->not_needed)
2938 return TRUE;
2939 break;
2941 case bfd_link_hash_warning:
2942 case bfd_link_hash_indirect:
2943 elf_smash_syms ((struct elf_link_hash_entry *) h->root.u.i.link, data);
2944 if (h->root.u.i.link->type != bfd_link_hash_new)
2945 return TRUE;
2946 if (h->root.u.i.link->u.undef.abfd != inf->not_needed)
2947 return TRUE;
2948 break;
2951 /* There is no way we can undo symbol table state from defined or
2952 defweak back to undefined. */
2953 if (h->ref_regular)
2954 abort ();
2956 /* Set sym back to newly created state, but keep undef.next if it is
2957 being used as a list pointer. */
2958 bh = h->root.u.undef.next;
2959 if (bh == &h->root)
2960 bh = NULL;
2961 if (bh != NULL || inf->htab->root.undefs_tail == &h->root)
2962 inf->twiddled = TRUE;
2963 (*inf->htab->root.table.newfunc) (&h->root.root,
2964 &inf->htab->root.table,
2965 h->root.root.string);
2966 h->root.u.undef.next = bh;
2967 h->root.u.undef.abfd = inf->not_needed;
2968 h->non_elf = 0;
2969 return TRUE;
2972 /* Sort symbol by value and section. */
2973 static int
2974 elf_sort_symbol (const void *arg1, const void *arg2)
2976 const struct elf_link_hash_entry *h1;
2977 const struct elf_link_hash_entry *h2;
2978 bfd_signed_vma vdiff;
2980 h1 = *(const struct elf_link_hash_entry **) arg1;
2981 h2 = *(const struct elf_link_hash_entry **) arg2;
2982 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2983 if (vdiff != 0)
2984 return vdiff > 0 ? 1 : -1;
2985 else
2987 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2988 if (sdiff != 0)
2989 return sdiff > 0 ? 1 : -1;
2991 return 0;
2994 /* This function is used to adjust offsets into .dynstr for
2995 dynamic symbols. This is called via elf_link_hash_traverse. */
2997 static bfd_boolean
2998 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3000 struct elf_strtab_hash *dynstr = data;
3002 if (h->root.type == bfd_link_hash_warning)
3003 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3005 if (h->dynindx != -1)
3006 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3007 return TRUE;
3010 /* Assign string offsets in .dynstr, update all structures referencing
3011 them. */
3013 static bfd_boolean
3014 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3016 struct elf_link_hash_table *hash_table = elf_hash_table (info);
3017 struct elf_link_local_dynamic_entry *entry;
3018 struct elf_strtab_hash *dynstr = hash_table->dynstr;
3019 bfd *dynobj = hash_table->dynobj;
3020 asection *sdyn;
3021 bfd_size_type size;
3022 const struct elf_backend_data *bed;
3023 bfd_byte *extdyn;
3025 _bfd_elf_strtab_finalize (dynstr);
3026 size = _bfd_elf_strtab_size (dynstr);
3028 bed = get_elf_backend_data (dynobj);
3029 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3030 BFD_ASSERT (sdyn != NULL);
3032 /* Update all .dynamic entries referencing .dynstr strings. */
3033 for (extdyn = sdyn->contents;
3034 extdyn < sdyn->contents + sdyn->size;
3035 extdyn += bed->s->sizeof_dyn)
3037 Elf_Internal_Dyn dyn;
3039 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3040 switch (dyn.d_tag)
3042 case DT_STRSZ:
3043 dyn.d_un.d_val = size;
3044 break;
3045 case DT_NEEDED:
3046 case DT_SONAME:
3047 case DT_RPATH:
3048 case DT_RUNPATH:
3049 case DT_FILTER:
3050 case DT_AUXILIARY:
3051 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3052 break;
3053 default:
3054 continue;
3056 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3059 /* Now update local dynamic symbols. */
3060 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3061 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3062 entry->isym.st_name);
3064 /* And the rest of dynamic symbols. */
3065 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3067 /* Adjust version definitions. */
3068 if (elf_tdata (output_bfd)->cverdefs)
3070 asection *s;
3071 bfd_byte *p;
3072 bfd_size_type i;
3073 Elf_Internal_Verdef def;
3074 Elf_Internal_Verdaux defaux;
3076 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3077 p = s->contents;
3080 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3081 &def);
3082 p += sizeof (Elf_External_Verdef);
3083 if (def.vd_aux != sizeof (Elf_External_Verdef))
3084 continue;
3085 for (i = 0; i < def.vd_cnt; ++i)
3087 _bfd_elf_swap_verdaux_in (output_bfd,
3088 (Elf_External_Verdaux *) p, &defaux);
3089 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3090 defaux.vda_name);
3091 _bfd_elf_swap_verdaux_out (output_bfd,
3092 &defaux, (Elf_External_Verdaux *) p);
3093 p += sizeof (Elf_External_Verdaux);
3096 while (def.vd_next);
3099 /* Adjust version references. */
3100 if (elf_tdata (output_bfd)->verref)
3102 asection *s;
3103 bfd_byte *p;
3104 bfd_size_type i;
3105 Elf_Internal_Verneed need;
3106 Elf_Internal_Vernaux needaux;
3108 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3109 p = s->contents;
3112 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3113 &need);
3114 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3115 _bfd_elf_swap_verneed_out (output_bfd, &need,
3116 (Elf_External_Verneed *) p);
3117 p += sizeof (Elf_External_Verneed);
3118 for (i = 0; i < need.vn_cnt; ++i)
3120 _bfd_elf_swap_vernaux_in (output_bfd,
3121 (Elf_External_Vernaux *) p, &needaux);
3122 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3123 needaux.vna_name);
3124 _bfd_elf_swap_vernaux_out (output_bfd,
3125 &needaux,
3126 (Elf_External_Vernaux *) p);
3127 p += sizeof (Elf_External_Vernaux);
3130 while (need.vn_next);
3133 return TRUE;
3136 /* Add symbols from an ELF object file to the linker hash table. */
3138 static bfd_boolean
3139 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3141 bfd_boolean (*add_symbol_hook)
3142 (bfd *, struct bfd_link_info *, Elf_Internal_Sym *,
3143 const char **, flagword *, asection **, bfd_vma *);
3144 bfd_boolean (*check_relocs)
3145 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
3146 bfd_boolean (*check_directives)
3147 (bfd *, struct bfd_link_info *);
3148 bfd_boolean collect;
3149 Elf_Internal_Shdr *hdr;
3150 bfd_size_type symcount;
3151 bfd_size_type extsymcount;
3152 bfd_size_type extsymoff;
3153 struct elf_link_hash_entry **sym_hash;
3154 bfd_boolean dynamic;
3155 Elf_External_Versym *extversym = NULL;
3156 Elf_External_Versym *ever;
3157 struct elf_link_hash_entry *weaks;
3158 struct elf_link_hash_entry **nondeflt_vers = NULL;
3159 bfd_size_type nondeflt_vers_cnt = 0;
3160 Elf_Internal_Sym *isymbuf = NULL;
3161 Elf_Internal_Sym *isym;
3162 Elf_Internal_Sym *isymend;
3163 const struct elf_backend_data *bed;
3164 bfd_boolean add_needed;
3165 struct elf_link_hash_table * hash_table;
3166 bfd_size_type amt;
3168 hash_table = elf_hash_table (info);
3170 bed = get_elf_backend_data (abfd);
3171 add_symbol_hook = bed->elf_add_symbol_hook;
3172 collect = bed->collect;
3174 if ((abfd->flags & DYNAMIC) == 0)
3175 dynamic = FALSE;
3176 else
3178 dynamic = TRUE;
3180 /* You can't use -r against a dynamic object. Also, there's no
3181 hope of using a dynamic object which does not exactly match
3182 the format of the output file. */
3183 if (info->relocatable
3184 || !is_elf_hash_table (hash_table)
3185 || hash_table->root.creator != abfd->xvec)
3187 if (info->relocatable)
3188 bfd_set_error (bfd_error_invalid_operation);
3189 else
3190 bfd_set_error (bfd_error_wrong_format);
3191 goto error_return;
3195 /* As a GNU extension, any input sections which are named
3196 .gnu.warning.SYMBOL are treated as warning symbols for the given
3197 symbol. This differs from .gnu.warning sections, which generate
3198 warnings when they are included in an output file. */
3199 if (info->executable)
3201 asection *s;
3203 for (s = abfd->sections; s != NULL; s = s->next)
3205 const char *name;
3207 name = bfd_get_section_name (abfd, s);
3208 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
3210 char *msg;
3211 bfd_size_type sz;
3213 name += sizeof ".gnu.warning." - 1;
3215 /* If this is a shared object, then look up the symbol
3216 in the hash table. If it is there, and it is already
3217 been defined, then we will not be using the entry
3218 from this shared object, so we don't need to warn.
3219 FIXME: If we see the definition in a regular object
3220 later on, we will warn, but we shouldn't. The only
3221 fix is to keep track of what warnings we are supposed
3222 to emit, and then handle them all at the end of the
3223 link. */
3224 if (dynamic)
3226 struct elf_link_hash_entry *h;
3228 h = elf_link_hash_lookup (hash_table, name,
3229 FALSE, FALSE, TRUE);
3231 /* FIXME: What about bfd_link_hash_common? */
3232 if (h != NULL
3233 && (h->root.type == bfd_link_hash_defined
3234 || h->root.type == bfd_link_hash_defweak))
3236 /* We don't want to issue this warning. Clobber
3237 the section size so that the warning does not
3238 get copied into the output file. */
3239 s->size = 0;
3240 continue;
3244 sz = s->size;
3245 msg = bfd_alloc (abfd, sz + 1);
3246 if (msg == NULL)
3247 goto error_return;
3249 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3250 goto error_return;
3252 msg[sz] = '\0';
3254 if (! (_bfd_generic_link_add_one_symbol
3255 (info, abfd, name, BSF_WARNING, s, 0, msg,
3256 FALSE, collect, NULL)))
3257 goto error_return;
3259 if (! info->relocatable)
3261 /* Clobber the section size so that the warning does
3262 not get copied into the output file. */
3263 s->size = 0;
3265 /* Also set SEC_EXCLUDE, so that symbols defined in
3266 the warning section don't get copied to the output. */
3267 s->flags |= SEC_EXCLUDE;
3273 add_needed = TRUE;
3274 if (! dynamic)
3276 /* If we are creating a shared library, create all the dynamic
3277 sections immediately. We need to attach them to something,
3278 so we attach them to this BFD, provided it is the right
3279 format. FIXME: If there are no input BFD's of the same
3280 format as the output, we can't make a shared library. */
3281 if (info->shared
3282 && is_elf_hash_table (hash_table)
3283 && hash_table->root.creator == abfd->xvec
3284 && ! hash_table->dynamic_sections_created)
3286 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3287 goto error_return;
3290 else if (!is_elf_hash_table (hash_table))
3291 goto error_return;
3292 else
3294 asection *s;
3295 const char *soname = NULL;
3296 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3297 int ret;
3299 /* ld --just-symbols and dynamic objects don't mix very well.
3300 Test for --just-symbols by looking at info set up by
3301 _bfd_elf_link_just_syms. */
3302 if ((s = abfd->sections) != NULL
3303 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3304 goto error_return;
3306 /* If this dynamic lib was specified on the command line with
3307 --as-needed in effect, then we don't want to add a DT_NEEDED
3308 tag unless the lib is actually used. Similary for libs brought
3309 in by another lib's DT_NEEDED. When --no-add-needed is used
3310 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3311 any dynamic library in DT_NEEDED tags in the dynamic lib at
3312 all. */
3313 add_needed = (elf_dyn_lib_class (abfd)
3314 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3315 | DYN_NO_NEEDED)) == 0;
3317 s = bfd_get_section_by_name (abfd, ".dynamic");
3318 if (s != NULL)
3320 bfd_byte *dynbuf;
3321 bfd_byte *extdyn;
3322 int elfsec;
3323 unsigned long shlink;
3325 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3326 goto error_free_dyn;
3328 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3329 if (elfsec == -1)
3330 goto error_free_dyn;
3331 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3333 for (extdyn = dynbuf;
3334 extdyn < dynbuf + s->size;
3335 extdyn += bed->s->sizeof_dyn)
3337 Elf_Internal_Dyn dyn;
3339 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3340 if (dyn.d_tag == DT_SONAME)
3342 unsigned int tagv = dyn.d_un.d_val;
3343 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3344 if (soname == NULL)
3345 goto error_free_dyn;
3347 if (dyn.d_tag == DT_NEEDED)
3349 struct bfd_link_needed_list *n, **pn;
3350 char *fnm, *anm;
3351 unsigned int tagv = dyn.d_un.d_val;
3353 amt = sizeof (struct bfd_link_needed_list);
3354 n = bfd_alloc (abfd, amt);
3355 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3356 if (n == NULL || fnm == NULL)
3357 goto error_free_dyn;
3358 amt = strlen (fnm) + 1;
3359 anm = bfd_alloc (abfd, amt);
3360 if (anm == NULL)
3361 goto error_free_dyn;
3362 memcpy (anm, fnm, amt);
3363 n->name = anm;
3364 n->by = abfd;
3365 n->next = NULL;
3366 for (pn = & hash_table->needed;
3367 *pn != NULL;
3368 pn = &(*pn)->next)
3370 *pn = n;
3372 if (dyn.d_tag == DT_RUNPATH)
3374 struct bfd_link_needed_list *n, **pn;
3375 char *fnm, *anm;
3376 unsigned int tagv = dyn.d_un.d_val;
3378 amt = sizeof (struct bfd_link_needed_list);
3379 n = bfd_alloc (abfd, amt);
3380 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3381 if (n == NULL || fnm == NULL)
3382 goto error_free_dyn;
3383 amt = strlen (fnm) + 1;
3384 anm = bfd_alloc (abfd, amt);
3385 if (anm == NULL)
3386 goto error_free_dyn;
3387 memcpy (anm, fnm, amt);
3388 n->name = anm;
3389 n->by = abfd;
3390 n->next = NULL;
3391 for (pn = & runpath;
3392 *pn != NULL;
3393 pn = &(*pn)->next)
3395 *pn = n;
3397 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3398 if (!runpath && dyn.d_tag == DT_RPATH)
3400 struct bfd_link_needed_list *n, **pn;
3401 char *fnm, *anm;
3402 unsigned int tagv = dyn.d_un.d_val;
3404 amt = sizeof (struct bfd_link_needed_list);
3405 n = bfd_alloc (abfd, amt);
3406 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3407 if (n == NULL || fnm == NULL)
3408 goto error_free_dyn;
3409 amt = strlen (fnm) + 1;
3410 anm = bfd_alloc (abfd, amt);
3411 if (anm == NULL)
3413 error_free_dyn:
3414 free (dynbuf);
3415 goto error_return;
3417 memcpy (anm, fnm, amt);
3418 n->name = anm;
3419 n->by = abfd;
3420 n->next = NULL;
3421 for (pn = & rpath;
3422 *pn != NULL;
3423 pn = &(*pn)->next)
3425 *pn = n;
3429 free (dynbuf);
3432 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3433 frees all more recently bfd_alloc'd blocks as well. */
3434 if (runpath)
3435 rpath = runpath;
3437 if (rpath)
3439 struct bfd_link_needed_list **pn;
3440 for (pn = & hash_table->runpath;
3441 *pn != NULL;
3442 pn = &(*pn)->next)
3444 *pn = rpath;
3447 /* We do not want to include any of the sections in a dynamic
3448 object in the output file. We hack by simply clobbering the
3449 list of sections in the BFD. This could be handled more
3450 cleanly by, say, a new section flag; the existing
3451 SEC_NEVER_LOAD flag is not the one we want, because that one
3452 still implies that the section takes up space in the output
3453 file. */
3454 bfd_section_list_clear (abfd);
3456 /* Find the name to use in a DT_NEEDED entry that refers to this
3457 object. If the object has a DT_SONAME entry, we use it.
3458 Otherwise, if the generic linker stuck something in
3459 elf_dt_name, we use that. Otherwise, we just use the file
3460 name. */
3461 if (soname == NULL || *soname == '\0')
3463 soname = elf_dt_name (abfd);
3464 if (soname == NULL || *soname == '\0')
3465 soname = bfd_get_filename (abfd);
3468 /* Save the SONAME because sometimes the linker emulation code
3469 will need to know it. */
3470 elf_dt_name (abfd) = soname;
3472 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3473 if (ret < 0)
3474 goto error_return;
3476 /* If we have already included this dynamic object in the
3477 link, just ignore it. There is no reason to include a
3478 particular dynamic object more than once. */
3479 if (ret > 0)
3480 return TRUE;
3483 /* If this is a dynamic object, we always link against the .dynsym
3484 symbol table, not the .symtab symbol table. The dynamic linker
3485 will only see the .dynsym symbol table, so there is no reason to
3486 look at .symtab for a dynamic object. */
3488 if (! dynamic || elf_dynsymtab (abfd) == 0)
3489 hdr = &elf_tdata (abfd)->symtab_hdr;
3490 else
3491 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3493 symcount = hdr->sh_size / bed->s->sizeof_sym;
3495 /* The sh_info field of the symtab header tells us where the
3496 external symbols start. We don't care about the local symbols at
3497 this point. */
3498 if (elf_bad_symtab (abfd))
3500 extsymcount = symcount;
3501 extsymoff = 0;
3503 else
3505 extsymcount = symcount - hdr->sh_info;
3506 extsymoff = hdr->sh_info;
3509 sym_hash = NULL;
3510 if (extsymcount != 0)
3512 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3513 NULL, NULL, NULL);
3514 if (isymbuf == NULL)
3515 goto error_return;
3517 /* We store a pointer to the hash table entry for each external
3518 symbol. */
3519 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3520 sym_hash = bfd_alloc (abfd, amt);
3521 if (sym_hash == NULL)
3522 goto error_free_sym;
3523 elf_sym_hashes (abfd) = sym_hash;
3526 if (dynamic)
3528 /* Read in any version definitions. */
3529 if (!_bfd_elf_slurp_version_tables (abfd,
3530 info->default_imported_symver))
3531 goto error_free_sym;
3533 /* Read in the symbol versions, but don't bother to convert them
3534 to internal format. */
3535 if (elf_dynversym (abfd) != 0)
3537 Elf_Internal_Shdr *versymhdr;
3539 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3540 extversym = bfd_malloc (versymhdr->sh_size);
3541 if (extversym == NULL)
3542 goto error_free_sym;
3543 amt = versymhdr->sh_size;
3544 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3545 || bfd_bread (extversym, amt, abfd) != amt)
3546 goto error_free_vers;
3550 weaks = NULL;
3552 ever = extversym != NULL ? extversym + extsymoff : NULL;
3553 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3554 isym < isymend;
3555 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3557 int bind;
3558 bfd_vma value;
3559 asection *sec, *new_sec;
3560 flagword flags;
3561 const char *name;
3562 struct elf_link_hash_entry *h;
3563 bfd_boolean definition;
3564 bfd_boolean size_change_ok;
3565 bfd_boolean type_change_ok;
3566 bfd_boolean new_weakdef;
3567 bfd_boolean override;
3568 bfd_boolean common;
3569 unsigned int old_alignment;
3570 bfd *old_bfd;
3572 override = FALSE;
3574 flags = BSF_NO_FLAGS;
3575 sec = NULL;
3576 value = isym->st_value;
3577 *sym_hash = NULL;
3578 common = bed->common_definition (isym);
3580 bind = ELF_ST_BIND (isym->st_info);
3581 if (bind == STB_LOCAL)
3583 /* This should be impossible, since ELF requires that all
3584 global symbols follow all local symbols, and that sh_info
3585 point to the first global symbol. Unfortunately, Irix 5
3586 screws this up. */
3587 continue;
3589 else if (bind == STB_GLOBAL)
3591 if (isym->st_shndx != SHN_UNDEF && !common)
3592 flags = BSF_GLOBAL;
3594 else if (bind == STB_WEAK)
3595 flags = BSF_WEAK;
3596 else
3598 /* Leave it up to the processor backend. */
3601 if (isym->st_shndx == SHN_UNDEF)
3602 sec = bfd_und_section_ptr;
3603 else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
3605 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3606 if (sec == NULL)
3607 sec = bfd_abs_section_ptr;
3608 else if (sec->kept_section)
3610 /* Symbols from discarded section are undefined, and have
3611 default visibility. */
3612 sec = bfd_und_section_ptr;
3613 isym->st_shndx = SHN_UNDEF;
3614 isym->st_other = STV_DEFAULT
3615 | (isym->st_other & ~ ELF_ST_VISIBILITY(-1));
3617 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3618 value -= sec->vma;
3620 else if (isym->st_shndx == SHN_ABS)
3621 sec = bfd_abs_section_ptr;
3622 else if (isym->st_shndx == SHN_COMMON)
3624 sec = bfd_com_section_ptr;
3625 /* What ELF calls the size we call the value. What ELF
3626 calls the value we call the alignment. */
3627 value = isym->st_size;
3629 else
3631 /* Leave it up to the processor backend. */
3634 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3635 isym->st_name);
3636 if (name == NULL)
3637 goto error_free_vers;
3639 if (isym->st_shndx == SHN_COMMON
3640 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3642 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3644 if (tcomm == NULL)
3646 tcomm = bfd_make_section_with_flags (abfd, ".tcommon",
3647 (SEC_ALLOC
3648 | SEC_IS_COMMON
3649 | SEC_LINKER_CREATED
3650 | SEC_THREAD_LOCAL));
3651 if (tcomm == NULL)
3652 goto error_free_vers;
3654 sec = tcomm;
3656 else if (add_symbol_hook)
3658 if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec,
3659 &value))
3660 goto error_free_vers;
3662 /* The hook function sets the name to NULL if this symbol
3663 should be skipped for some reason. */
3664 if (name == NULL)
3665 continue;
3668 /* Sanity check that all possibilities were handled. */
3669 if (sec == NULL)
3671 bfd_set_error (bfd_error_bad_value);
3672 goto error_free_vers;
3675 if (bfd_is_und_section (sec)
3676 || bfd_is_com_section (sec))
3677 definition = FALSE;
3678 else
3679 definition = TRUE;
3681 size_change_ok = FALSE;
3682 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
3683 old_alignment = 0;
3684 old_bfd = NULL;
3685 new_sec = sec;
3687 if (is_elf_hash_table (hash_table))
3689 Elf_Internal_Versym iver;
3690 unsigned int vernum = 0;
3691 bfd_boolean skip;
3693 if (ever == NULL)
3695 if (info->default_imported_symver)
3696 /* Use the default symbol version created earlier. */
3697 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3698 else
3699 iver.vs_vers = 0;
3701 else
3702 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3704 vernum = iver.vs_vers & VERSYM_VERSION;
3706 /* If this is a hidden symbol, or if it is not version
3707 1, we append the version name to the symbol name.
3708 However, we do not modify a non-hidden absolute symbol
3709 if it is not a function, because it might be the version
3710 symbol itself. FIXME: What if it isn't? */
3711 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3712 || (vernum > 1 && (! bfd_is_abs_section (sec)
3713 || ELF_ST_TYPE (isym->st_info) == STT_FUNC)))
3715 const char *verstr;
3716 size_t namelen, verlen, newlen;
3717 char *newname, *p;
3719 if (isym->st_shndx != SHN_UNDEF)
3721 if (vernum > elf_tdata (abfd)->cverdefs)
3722 verstr = NULL;
3723 else if (vernum > 1)
3724 verstr =
3725 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3726 else
3727 verstr = "";
3729 if (verstr == NULL)
3731 (*_bfd_error_handler)
3732 (_("%B: %s: invalid version %u (max %d)"),
3733 abfd, name, vernum,
3734 elf_tdata (abfd)->cverdefs);
3735 bfd_set_error (bfd_error_bad_value);
3736 goto error_free_vers;
3739 else
3741 /* We cannot simply test for the number of
3742 entries in the VERNEED section since the
3743 numbers for the needed versions do not start
3744 at 0. */
3745 Elf_Internal_Verneed *t;
3747 verstr = NULL;
3748 for (t = elf_tdata (abfd)->verref;
3749 t != NULL;
3750 t = t->vn_nextref)
3752 Elf_Internal_Vernaux *a;
3754 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3756 if (a->vna_other == vernum)
3758 verstr = a->vna_nodename;
3759 break;
3762 if (a != NULL)
3763 break;
3765 if (verstr == NULL)
3767 (*_bfd_error_handler)
3768 (_("%B: %s: invalid needed version %d"),
3769 abfd, name, vernum);
3770 bfd_set_error (bfd_error_bad_value);
3771 goto error_free_vers;
3775 namelen = strlen (name);
3776 verlen = strlen (verstr);
3777 newlen = namelen + verlen + 2;
3778 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3779 && isym->st_shndx != SHN_UNDEF)
3780 ++newlen;
3782 newname = bfd_alloc (abfd, newlen);
3783 if (newname == NULL)
3784 goto error_free_vers;
3785 memcpy (newname, name, namelen);
3786 p = newname + namelen;
3787 *p++ = ELF_VER_CHR;
3788 /* If this is a defined non-hidden version symbol,
3789 we add another @ to the name. This indicates the
3790 default version of the symbol. */
3791 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3792 && isym->st_shndx != SHN_UNDEF)
3793 *p++ = ELF_VER_CHR;
3794 memcpy (p, verstr, verlen + 1);
3796 name = newname;
3799 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
3800 &value, &old_alignment,
3801 sym_hash, &skip, &override,
3802 &type_change_ok, &size_change_ok))
3803 goto error_free_vers;
3805 if (skip)
3806 continue;
3808 if (override)
3809 definition = FALSE;
3811 h = *sym_hash;
3812 while (h->root.type == bfd_link_hash_indirect
3813 || h->root.type == bfd_link_hash_warning)
3814 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3816 /* Remember the old alignment if this is a common symbol, so
3817 that we don't reduce the alignment later on. We can't
3818 check later, because _bfd_generic_link_add_one_symbol
3819 will set a default for the alignment which we want to
3820 override. We also remember the old bfd where the existing
3821 definition comes from. */
3822 switch (h->root.type)
3824 default:
3825 break;
3827 case bfd_link_hash_defined:
3828 case bfd_link_hash_defweak:
3829 old_bfd = h->root.u.def.section->owner;
3830 break;
3832 case bfd_link_hash_common:
3833 old_bfd = h->root.u.c.p->section->owner;
3834 old_alignment = h->root.u.c.p->alignment_power;
3835 break;
3838 if (elf_tdata (abfd)->verdef != NULL
3839 && ! override
3840 && vernum > 1
3841 && definition)
3842 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3845 if (! (_bfd_generic_link_add_one_symbol
3846 (info, abfd, name, flags, sec, value, NULL, FALSE, collect,
3847 (struct bfd_link_hash_entry **) sym_hash)))
3848 goto error_free_vers;
3850 h = *sym_hash;
3851 while (h->root.type == bfd_link_hash_indirect
3852 || h->root.type == bfd_link_hash_warning)
3853 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3854 *sym_hash = h;
3856 new_weakdef = FALSE;
3857 if (dynamic
3858 && definition
3859 && (flags & BSF_WEAK) != 0
3860 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3861 && is_elf_hash_table (hash_table)
3862 && h->u.weakdef == NULL)
3864 /* Keep a list of all weak defined non function symbols from
3865 a dynamic object, using the weakdef field. Later in this
3866 function we will set the weakdef field to the correct
3867 value. We only put non-function symbols from dynamic
3868 objects on this list, because that happens to be the only
3869 time we need to know the normal symbol corresponding to a
3870 weak symbol, and the information is time consuming to
3871 figure out. If the weakdef field is not already NULL,
3872 then this symbol was already defined by some previous
3873 dynamic object, and we will be using that previous
3874 definition anyhow. */
3876 h->u.weakdef = weaks;
3877 weaks = h;
3878 new_weakdef = TRUE;
3881 /* Set the alignment of a common symbol. */
3882 if ((common || bfd_is_com_section (sec))
3883 && h->root.type == bfd_link_hash_common)
3885 unsigned int align;
3887 if (common)
3888 align = bfd_log2 (isym->st_value);
3889 else
3891 /* The new symbol is a common symbol in a shared object.
3892 We need to get the alignment from the section. */
3893 align = new_sec->alignment_power;
3895 if (align > old_alignment
3896 /* Permit an alignment power of zero if an alignment of one
3897 is specified and no other alignments have been specified. */
3898 || (isym->st_value == 1 && old_alignment == 0))
3899 h->root.u.c.p->alignment_power = align;
3900 else
3901 h->root.u.c.p->alignment_power = old_alignment;
3904 if (is_elf_hash_table (hash_table))
3906 bfd_boolean dynsym;
3908 /* Check the alignment when a common symbol is involved. This
3909 can change when a common symbol is overridden by a normal
3910 definition or a common symbol is ignored due to the old
3911 normal definition. We need to make sure the maximum
3912 alignment is maintained. */
3913 if ((old_alignment || common)
3914 && h->root.type != bfd_link_hash_common)
3916 unsigned int common_align;
3917 unsigned int normal_align;
3918 unsigned int symbol_align;
3919 bfd *normal_bfd;
3920 bfd *common_bfd;
3922 symbol_align = ffs (h->root.u.def.value) - 1;
3923 if (h->root.u.def.section->owner != NULL
3924 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3926 normal_align = h->root.u.def.section->alignment_power;
3927 if (normal_align > symbol_align)
3928 normal_align = symbol_align;
3930 else
3931 normal_align = symbol_align;
3933 if (old_alignment)
3935 common_align = old_alignment;
3936 common_bfd = old_bfd;
3937 normal_bfd = abfd;
3939 else
3941 common_align = bfd_log2 (isym->st_value);
3942 common_bfd = abfd;
3943 normal_bfd = old_bfd;
3946 if (normal_align < common_align)
3947 (*_bfd_error_handler)
3948 (_("Warning: alignment %u of symbol `%s' in %B"
3949 " is smaller than %u in %B"),
3950 normal_bfd, common_bfd,
3951 1 << normal_align, name, 1 << common_align);
3954 /* Remember the symbol size and type. */
3955 if (isym->st_size != 0
3956 && (definition || h->size == 0))
3958 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3959 (*_bfd_error_handler)
3960 (_("Warning: size of symbol `%s' changed"
3961 " from %lu in %B to %lu in %B"),
3962 old_bfd, abfd,
3963 name, (unsigned long) h->size,
3964 (unsigned long) isym->st_size);
3966 h->size = isym->st_size;
3969 /* If this is a common symbol, then we always want H->SIZE
3970 to be the size of the common symbol. The code just above
3971 won't fix the size if a common symbol becomes larger. We
3972 don't warn about a size change here, because that is
3973 covered by --warn-common. */
3974 if (h->root.type == bfd_link_hash_common)
3975 h->size = h->root.u.c.size;
3977 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3978 && (definition || h->type == STT_NOTYPE))
3980 if (h->type != STT_NOTYPE
3981 && h->type != ELF_ST_TYPE (isym->st_info)
3982 && ! type_change_ok)
3983 (*_bfd_error_handler)
3984 (_("Warning: type of symbol `%s' changed"
3985 " from %d to %d in %B"),
3986 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
3988 h->type = ELF_ST_TYPE (isym->st_info);
3991 /* If st_other has a processor-specific meaning, specific
3992 code might be needed here. We never merge the visibility
3993 attribute with the one from a dynamic object. */
3994 if (bed->elf_backend_merge_symbol_attribute)
3995 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3996 dynamic);
3998 /* If this symbol has default visibility and the user has requested
3999 we not re-export it, then mark it as hidden. */
4000 if (definition && !dynamic
4001 && (abfd->no_export
4002 || (abfd->my_archive && abfd->my_archive->no_export))
4003 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
4004 isym->st_other = STV_HIDDEN | (isym->st_other & ~ ELF_ST_VISIBILITY (-1));
4006 if (isym->st_other != 0 && !dynamic)
4008 unsigned char hvis, symvis, other, nvis;
4010 /* Take the balance of OTHER from the definition. */
4011 other = (definition ? isym->st_other : h->other);
4012 other &= ~ ELF_ST_VISIBILITY (-1);
4014 /* Combine visibilities, using the most constraining one. */
4015 hvis = ELF_ST_VISIBILITY (h->other);
4016 symvis = ELF_ST_VISIBILITY (isym->st_other);
4017 if (! hvis)
4018 nvis = symvis;
4019 else if (! symvis)
4020 nvis = hvis;
4021 else
4022 nvis = hvis < symvis ? hvis : symvis;
4024 h->other = other | nvis;
4027 /* Set a flag in the hash table entry indicating the type of
4028 reference or definition we just found. Keep a count of
4029 the number of dynamic symbols we find. A dynamic symbol
4030 is one which is referenced or defined by both a regular
4031 object and a shared object. */
4032 dynsym = FALSE;
4033 if (! dynamic)
4035 if (! definition)
4037 h->ref_regular = 1;
4038 if (bind != STB_WEAK)
4039 h->ref_regular_nonweak = 1;
4041 else
4042 h->def_regular = 1;
4043 if (! info->executable
4044 || h->def_dynamic
4045 || h->ref_dynamic)
4046 dynsym = TRUE;
4048 else
4050 if (! definition)
4051 h->ref_dynamic = 1;
4052 else
4053 h->def_dynamic = 1;
4054 if (h->def_regular
4055 || h->ref_regular
4056 || (h->u.weakdef != NULL
4057 && ! new_weakdef
4058 && h->u.weakdef->dynindx != -1))
4059 dynsym = TRUE;
4062 /* Check to see if we need to add an indirect symbol for
4063 the default name. */
4064 if (definition || h->root.type == bfd_link_hash_common)
4065 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4066 &sec, &value, &dynsym,
4067 override))
4068 goto error_free_vers;
4070 if (definition && !dynamic)
4072 char *p = strchr (name, ELF_VER_CHR);
4073 if (p != NULL && p[1] != ELF_VER_CHR)
4075 /* Queue non-default versions so that .symver x, x@FOO
4076 aliases can be checked. */
4077 if (! nondeflt_vers)
4079 amt = (isymend - isym + 1)
4080 * sizeof (struct elf_link_hash_entry *);
4081 nondeflt_vers = bfd_malloc (amt);
4083 nondeflt_vers [nondeflt_vers_cnt++] = h;
4087 if (dynsym && h->dynindx == -1)
4089 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4090 goto error_free_vers;
4091 if (h->u.weakdef != NULL
4092 && ! new_weakdef
4093 && h->u.weakdef->dynindx == -1)
4095 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4096 goto error_free_vers;
4099 else if (dynsym && h->dynindx != -1)
4100 /* If the symbol already has a dynamic index, but
4101 visibility says it should not be visible, turn it into
4102 a local symbol. */
4103 switch (ELF_ST_VISIBILITY (h->other))
4105 case STV_INTERNAL:
4106 case STV_HIDDEN:
4107 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4108 dynsym = FALSE;
4109 break;
4112 if (!add_needed
4113 && definition
4114 && dynsym
4115 && h->ref_regular)
4117 int ret;
4118 const char *soname = elf_dt_name (abfd);
4120 /* A symbol from a library loaded via DT_NEEDED of some
4121 other library is referenced by a regular object.
4122 Add a DT_NEEDED entry for it. Issue an error if
4123 --no-add-needed is used. */
4124 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4126 (*_bfd_error_handler)
4127 (_("%s: invalid DSO for symbol `%s' definition"),
4128 abfd, name);
4129 bfd_set_error (bfd_error_bad_value);
4130 goto error_free_vers;
4133 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4135 add_needed = TRUE;
4136 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4137 if (ret < 0)
4138 goto error_free_vers;
4140 BFD_ASSERT (ret == 0);
4145 /* Now that all the symbols from this input file are created, handle
4146 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4147 if (nondeflt_vers != NULL)
4149 bfd_size_type cnt, symidx;
4151 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4153 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4154 char *shortname, *p;
4156 p = strchr (h->root.root.string, ELF_VER_CHR);
4157 if (p == NULL
4158 || (h->root.type != bfd_link_hash_defined
4159 && h->root.type != bfd_link_hash_defweak))
4160 continue;
4162 amt = p - h->root.root.string;
4163 shortname = bfd_malloc (amt + 1);
4164 memcpy (shortname, h->root.root.string, amt);
4165 shortname[amt] = '\0';
4167 hi = (struct elf_link_hash_entry *)
4168 bfd_link_hash_lookup (&hash_table->root, shortname,
4169 FALSE, FALSE, FALSE);
4170 if (hi != NULL
4171 && hi->root.type == h->root.type
4172 && hi->root.u.def.value == h->root.u.def.value
4173 && hi->root.u.def.section == h->root.u.def.section)
4175 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4176 hi->root.type = bfd_link_hash_indirect;
4177 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4178 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
4179 sym_hash = elf_sym_hashes (abfd);
4180 if (sym_hash)
4181 for (symidx = 0; symidx < extsymcount; ++symidx)
4182 if (sym_hash[symidx] == hi)
4184 sym_hash[symidx] = h;
4185 break;
4188 free (shortname);
4190 free (nondeflt_vers);
4191 nondeflt_vers = NULL;
4194 if (extversym != NULL)
4196 free (extversym);
4197 extversym = NULL;
4200 if (isymbuf != NULL)
4201 free (isymbuf);
4202 isymbuf = NULL;
4204 if (!add_needed
4205 && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4207 /* Remove symbols defined in an as-needed shared lib that wasn't
4208 needed. */
4209 struct elf_smash_syms_data inf;
4210 inf.not_needed = abfd;
4211 inf.htab = hash_table;
4212 inf.twiddled = FALSE;
4213 elf_link_hash_traverse (hash_table, elf_smash_syms, &inf);
4214 if (inf.twiddled)
4215 bfd_link_repair_undef_list (&hash_table->root);
4216 weaks = NULL;
4219 /* Now set the weakdefs field correctly for all the weak defined
4220 symbols we found. The only way to do this is to search all the
4221 symbols. Since we only need the information for non functions in
4222 dynamic objects, that's the only time we actually put anything on
4223 the list WEAKS. We need this information so that if a regular
4224 object refers to a symbol defined weakly in a dynamic object, the
4225 real symbol in the dynamic object is also put in the dynamic
4226 symbols; we also must arrange for both symbols to point to the
4227 same memory location. We could handle the general case of symbol
4228 aliasing, but a general symbol alias can only be generated in
4229 assembler code, handling it correctly would be very time
4230 consuming, and other ELF linkers don't handle general aliasing
4231 either. */
4232 if (weaks != NULL)
4234 struct elf_link_hash_entry **hpp;
4235 struct elf_link_hash_entry **hppend;
4236 struct elf_link_hash_entry **sorted_sym_hash;
4237 struct elf_link_hash_entry *h;
4238 size_t sym_count;
4240 /* Since we have to search the whole symbol list for each weak
4241 defined symbol, search time for N weak defined symbols will be
4242 O(N^2). Binary search will cut it down to O(NlogN). */
4243 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4244 sorted_sym_hash = bfd_malloc (amt);
4245 if (sorted_sym_hash == NULL)
4246 goto error_return;
4247 sym_hash = sorted_sym_hash;
4248 hpp = elf_sym_hashes (abfd);
4249 hppend = hpp + extsymcount;
4250 sym_count = 0;
4251 for (; hpp < hppend; hpp++)
4253 h = *hpp;
4254 if (h != NULL
4255 && h->root.type == bfd_link_hash_defined
4256 && h->type != STT_FUNC)
4258 *sym_hash = h;
4259 sym_hash++;
4260 sym_count++;
4264 qsort (sorted_sym_hash, sym_count,
4265 sizeof (struct elf_link_hash_entry *),
4266 elf_sort_symbol);
4268 while (weaks != NULL)
4270 struct elf_link_hash_entry *hlook;
4271 asection *slook;
4272 bfd_vma vlook;
4273 long ilook;
4274 size_t i, j, idx;
4276 hlook = weaks;
4277 weaks = hlook->u.weakdef;
4278 hlook->u.weakdef = NULL;
4280 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4281 || hlook->root.type == bfd_link_hash_defweak
4282 || hlook->root.type == bfd_link_hash_common
4283 || hlook->root.type == bfd_link_hash_indirect);
4284 slook = hlook->root.u.def.section;
4285 vlook = hlook->root.u.def.value;
4287 ilook = -1;
4288 i = 0;
4289 j = sym_count;
4290 while (i < j)
4292 bfd_signed_vma vdiff;
4293 idx = (i + j) / 2;
4294 h = sorted_sym_hash [idx];
4295 vdiff = vlook - h->root.u.def.value;
4296 if (vdiff < 0)
4297 j = idx;
4298 else if (vdiff > 0)
4299 i = idx + 1;
4300 else
4302 long sdiff = slook->id - h->root.u.def.section->id;
4303 if (sdiff < 0)
4304 j = idx;
4305 else if (sdiff > 0)
4306 i = idx + 1;
4307 else
4309 ilook = idx;
4310 break;
4315 /* We didn't find a value/section match. */
4316 if (ilook == -1)
4317 continue;
4319 for (i = ilook; i < sym_count; i++)
4321 h = sorted_sym_hash [i];
4323 /* Stop if value or section doesn't match. */
4324 if (h->root.u.def.value != vlook
4325 || h->root.u.def.section != slook)
4326 break;
4327 else if (h != hlook)
4329 hlook->u.weakdef = h;
4331 /* If the weak definition is in the list of dynamic
4332 symbols, make sure the real definition is put
4333 there as well. */
4334 if (hlook->dynindx != -1 && h->dynindx == -1)
4336 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4337 goto error_return;
4340 /* If the real definition is in the list of dynamic
4341 symbols, make sure the weak definition is put
4342 there as well. If we don't do this, then the
4343 dynamic loader might not merge the entries for the
4344 real definition and the weak definition. */
4345 if (h->dynindx != -1 && hlook->dynindx == -1)
4347 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4348 goto error_return;
4350 break;
4355 free (sorted_sym_hash);
4358 check_directives = get_elf_backend_data (abfd)->check_directives;
4359 if (check_directives)
4360 check_directives (abfd, info);
4362 /* If this object is the same format as the output object, and it is
4363 not a shared library, then let the backend look through the
4364 relocs.
4366 This is required to build global offset table entries and to
4367 arrange for dynamic relocs. It is not required for the
4368 particular common case of linking non PIC code, even when linking
4369 against shared libraries, but unfortunately there is no way of
4370 knowing whether an object file has been compiled PIC or not.
4371 Looking through the relocs is not particularly time consuming.
4372 The problem is that we must either (1) keep the relocs in memory,
4373 which causes the linker to require additional runtime memory or
4374 (2) read the relocs twice from the input file, which wastes time.
4375 This would be a good case for using mmap.
4377 I have no idea how to handle linking PIC code into a file of a
4378 different format. It probably can't be done. */
4379 check_relocs = get_elf_backend_data (abfd)->check_relocs;
4380 if (! dynamic
4381 && is_elf_hash_table (hash_table)
4382 && hash_table->root.creator == abfd->xvec
4383 && check_relocs != NULL)
4385 asection *o;
4387 for (o = abfd->sections; o != NULL; o = o->next)
4389 Elf_Internal_Rela *internal_relocs;
4390 bfd_boolean ok;
4392 if ((o->flags & SEC_RELOC) == 0
4393 || o->reloc_count == 0
4394 || ((info->strip == strip_all || info->strip == strip_debugger)
4395 && (o->flags & SEC_DEBUGGING) != 0)
4396 || bfd_is_abs_section (o->output_section))
4397 continue;
4399 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4400 info->keep_memory);
4401 if (internal_relocs == NULL)
4402 goto error_return;
4404 ok = (*check_relocs) (abfd, info, o, internal_relocs);
4406 if (elf_section_data (o)->relocs != internal_relocs)
4407 free (internal_relocs);
4409 if (! ok)
4410 goto error_return;
4414 /* If this is a non-traditional link, try to optimize the handling
4415 of the .stab/.stabstr sections. */
4416 if (! dynamic
4417 && ! info->traditional_format
4418 && is_elf_hash_table (hash_table)
4419 && (info->strip != strip_all && info->strip != strip_debugger))
4421 asection *stabstr;
4423 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4424 if (stabstr != NULL)
4426 bfd_size_type string_offset = 0;
4427 asection *stab;
4429 for (stab = abfd->sections; stab; stab = stab->next)
4430 if (strncmp (".stab", stab->name, 5) == 0
4431 && (!stab->name[5] ||
4432 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4433 && (stab->flags & SEC_MERGE) == 0
4434 && !bfd_is_abs_section (stab->output_section))
4436 struct bfd_elf_section_data *secdata;
4438 secdata = elf_section_data (stab);
4439 if (! _bfd_link_section_stabs (abfd,
4440 &hash_table->stab_info,
4441 stab, stabstr,
4442 &secdata->sec_info,
4443 &string_offset))
4444 goto error_return;
4445 if (secdata->sec_info)
4446 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4451 if (is_elf_hash_table (hash_table) && add_needed)
4453 /* Add this bfd to the loaded list. */
4454 struct elf_link_loaded_list *n;
4456 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4457 if (n == NULL)
4458 goto error_return;
4459 n->abfd = abfd;
4460 n->next = hash_table->loaded;
4461 hash_table->loaded = n;
4464 return TRUE;
4466 error_free_vers:
4467 if (nondeflt_vers != NULL)
4468 free (nondeflt_vers);
4469 if (extversym != NULL)
4470 free (extversym);
4471 error_free_sym:
4472 if (isymbuf != NULL)
4473 free (isymbuf);
4474 error_return:
4475 return FALSE;
4478 /* Return the linker hash table entry of a symbol that might be
4479 satisfied by an archive symbol. Return -1 on error. */
4481 struct elf_link_hash_entry *
4482 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4483 struct bfd_link_info *info,
4484 const char *name)
4486 struct elf_link_hash_entry *h;
4487 char *p, *copy;
4488 size_t len, first;
4490 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4491 if (h != NULL)
4492 return h;
4494 /* If this is a default version (the name contains @@), look up the
4495 symbol again with only one `@' as well as without the version.
4496 The effect is that references to the symbol with and without the
4497 version will be matched by the default symbol in the archive. */
4499 p = strchr (name, ELF_VER_CHR);
4500 if (p == NULL || p[1] != ELF_VER_CHR)
4501 return h;
4503 /* First check with only one `@'. */
4504 len = strlen (name);
4505 copy = bfd_alloc (abfd, len);
4506 if (copy == NULL)
4507 return (struct elf_link_hash_entry *) 0 - 1;
4509 first = p - name + 1;
4510 memcpy (copy, name, first);
4511 memcpy (copy + first, name + first + 1, len - first);
4513 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4514 if (h == NULL)
4516 /* We also need to check references to the symbol without the
4517 version. */
4518 copy[first - 1] = '\0';
4519 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4520 FALSE, FALSE, FALSE);
4523 bfd_release (abfd, copy);
4524 return h;
4527 /* Add symbols from an ELF archive file to the linker hash table. We
4528 don't use _bfd_generic_link_add_archive_symbols because of a
4529 problem which arises on UnixWare. The UnixWare libc.so is an
4530 archive which includes an entry libc.so.1 which defines a bunch of
4531 symbols. The libc.so archive also includes a number of other
4532 object files, which also define symbols, some of which are the same
4533 as those defined in libc.so.1. Correct linking requires that we
4534 consider each object file in turn, and include it if it defines any
4535 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4536 this; it looks through the list of undefined symbols, and includes
4537 any object file which defines them. When this algorithm is used on
4538 UnixWare, it winds up pulling in libc.so.1 early and defining a
4539 bunch of symbols. This means that some of the other objects in the
4540 archive are not included in the link, which is incorrect since they
4541 precede libc.so.1 in the archive.
4543 Fortunately, ELF archive handling is simpler than that done by
4544 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4545 oddities. In ELF, if we find a symbol in the archive map, and the
4546 symbol is currently undefined, we know that we must pull in that
4547 object file.
4549 Unfortunately, we do have to make multiple passes over the symbol
4550 table until nothing further is resolved. */
4552 static bfd_boolean
4553 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4555 symindex c;
4556 bfd_boolean *defined = NULL;
4557 bfd_boolean *included = NULL;
4558 carsym *symdefs;
4559 bfd_boolean loop;
4560 bfd_size_type amt;
4561 const struct elf_backend_data *bed;
4562 struct elf_link_hash_entry * (*archive_symbol_lookup)
4563 (bfd *, struct bfd_link_info *, const char *);
4565 if (! bfd_has_map (abfd))
4567 /* An empty archive is a special case. */
4568 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4569 return TRUE;
4570 bfd_set_error (bfd_error_no_armap);
4571 return FALSE;
4574 /* Keep track of all symbols we know to be already defined, and all
4575 files we know to be already included. This is to speed up the
4576 second and subsequent passes. */
4577 c = bfd_ardata (abfd)->symdef_count;
4578 if (c == 0)
4579 return TRUE;
4580 amt = c;
4581 amt *= sizeof (bfd_boolean);
4582 defined = bfd_zmalloc (amt);
4583 included = bfd_zmalloc (amt);
4584 if (defined == NULL || included == NULL)
4585 goto error_return;
4587 symdefs = bfd_ardata (abfd)->symdefs;
4588 bed = get_elf_backend_data (abfd);
4589 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4593 file_ptr last;
4594 symindex i;
4595 carsym *symdef;
4596 carsym *symdefend;
4598 loop = FALSE;
4599 last = -1;
4601 symdef = symdefs;
4602 symdefend = symdef + c;
4603 for (i = 0; symdef < symdefend; symdef++, i++)
4605 struct elf_link_hash_entry *h;
4606 bfd *element;
4607 struct bfd_link_hash_entry *undefs_tail;
4608 symindex mark;
4610 if (defined[i] || included[i])
4611 continue;
4612 if (symdef->file_offset == last)
4614 included[i] = TRUE;
4615 continue;
4618 h = archive_symbol_lookup (abfd, info, symdef->name);
4619 if (h == (struct elf_link_hash_entry *) 0 - 1)
4620 goto error_return;
4622 if (h == NULL)
4623 continue;
4625 if (h->root.type == bfd_link_hash_common)
4627 /* We currently have a common symbol. The archive map contains
4628 a reference to this symbol, so we may want to include it. We
4629 only want to include it however, if this archive element
4630 contains a definition of the symbol, not just another common
4631 declaration of it.
4633 Unfortunately some archivers (including GNU ar) will put
4634 declarations of common symbols into their archive maps, as
4635 well as real definitions, so we cannot just go by the archive
4636 map alone. Instead we must read in the element's symbol
4637 table and check that to see what kind of symbol definition
4638 this is. */
4639 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4640 continue;
4642 else if (h->root.type != bfd_link_hash_undefined)
4644 if (h->root.type != bfd_link_hash_undefweak)
4645 defined[i] = TRUE;
4646 continue;
4649 /* We need to include this archive member. */
4650 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4651 if (element == NULL)
4652 goto error_return;
4654 if (! bfd_check_format (element, bfd_object))
4655 goto error_return;
4657 /* Doublecheck that we have not included this object
4658 already--it should be impossible, but there may be
4659 something wrong with the archive. */
4660 if (element->archive_pass != 0)
4662 bfd_set_error (bfd_error_bad_value);
4663 goto error_return;
4665 element->archive_pass = 1;
4667 undefs_tail = info->hash->undefs_tail;
4669 if (! (*info->callbacks->add_archive_element) (info, element,
4670 symdef->name))
4671 goto error_return;
4672 if (! bfd_link_add_symbols (element, info))
4673 goto error_return;
4675 /* If there are any new undefined symbols, we need to make
4676 another pass through the archive in order to see whether
4677 they can be defined. FIXME: This isn't perfect, because
4678 common symbols wind up on undefs_tail and because an
4679 undefined symbol which is defined later on in this pass
4680 does not require another pass. This isn't a bug, but it
4681 does make the code less efficient than it could be. */
4682 if (undefs_tail != info->hash->undefs_tail)
4683 loop = TRUE;
4685 /* Look backward to mark all symbols from this object file
4686 which we have already seen in this pass. */
4687 mark = i;
4690 included[mark] = TRUE;
4691 if (mark == 0)
4692 break;
4693 --mark;
4695 while (symdefs[mark].file_offset == symdef->file_offset);
4697 /* We mark subsequent symbols from this object file as we go
4698 on through the loop. */
4699 last = symdef->file_offset;
4702 while (loop);
4704 free (defined);
4705 free (included);
4707 return TRUE;
4709 error_return:
4710 if (defined != NULL)
4711 free (defined);
4712 if (included != NULL)
4713 free (included);
4714 return FALSE;
4717 /* Given an ELF BFD, add symbols to the global hash table as
4718 appropriate. */
4720 bfd_boolean
4721 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4723 switch (bfd_get_format (abfd))
4725 case bfd_object:
4726 return elf_link_add_object_symbols (abfd, info);
4727 case bfd_archive:
4728 return elf_link_add_archive_symbols (abfd, info);
4729 default:
4730 bfd_set_error (bfd_error_wrong_format);
4731 return FALSE;
4735 /* This function will be called though elf_link_hash_traverse to store
4736 all hash value of the exported symbols in an array. */
4738 static bfd_boolean
4739 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4741 unsigned long **valuep = data;
4742 const char *name;
4743 char *p;
4744 unsigned long ha;
4745 char *alc = NULL;
4747 if (h->root.type == bfd_link_hash_warning)
4748 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4750 /* Ignore indirect symbols. These are added by the versioning code. */
4751 if (h->dynindx == -1)
4752 return TRUE;
4754 name = h->root.root.string;
4755 p = strchr (name, ELF_VER_CHR);
4756 if (p != NULL)
4758 alc = bfd_malloc (p - name + 1);
4759 memcpy (alc, name, p - name);
4760 alc[p - name] = '\0';
4761 name = alc;
4764 /* Compute the hash value. */
4765 ha = bfd_elf_hash (name);
4767 /* Store the found hash value in the array given as the argument. */
4768 *(*valuep)++ = ha;
4770 /* And store it in the struct so that we can put it in the hash table
4771 later. */
4772 h->u.elf_hash_value = ha;
4774 if (alc != NULL)
4775 free (alc);
4777 return TRUE;
4780 /* Array used to determine the number of hash table buckets to use
4781 based on the number of symbols there are. If there are fewer than
4782 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4783 fewer than 37 we use 17 buckets, and so forth. We never use more
4784 than 32771 buckets. */
4786 static const size_t elf_buckets[] =
4788 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4789 16411, 32771, 0
4792 /* Compute bucket count for hashing table. We do not use a static set
4793 of possible tables sizes anymore. Instead we determine for all
4794 possible reasonable sizes of the table the outcome (i.e., the
4795 number of collisions etc) and choose the best solution. The
4796 weighting functions are not too simple to allow the table to grow
4797 without bounds. Instead one of the weighting factors is the size.
4798 Therefore the result is always a good payoff between few collisions
4799 (= short chain lengths) and table size. */
4800 static size_t
4801 compute_bucket_count (struct bfd_link_info *info)
4803 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4804 size_t best_size = 0;
4805 unsigned long int *hashcodes;
4806 unsigned long int *hashcodesp;
4807 unsigned long int i;
4808 bfd_size_type amt;
4810 /* Compute the hash values for all exported symbols. At the same
4811 time store the values in an array so that we could use them for
4812 optimizations. */
4813 amt = dynsymcount;
4814 amt *= sizeof (unsigned long int);
4815 hashcodes = bfd_malloc (amt);
4816 if (hashcodes == NULL)
4817 return 0;
4818 hashcodesp = hashcodes;
4820 /* Put all hash values in HASHCODES. */
4821 elf_link_hash_traverse (elf_hash_table (info),
4822 elf_collect_hash_codes, &hashcodesp);
4824 /* We have a problem here. The following code to optimize the table
4825 size requires an integer type with more the 32 bits. If
4826 BFD_HOST_U_64_BIT is set we know about such a type. */
4827 #ifdef BFD_HOST_U_64_BIT
4828 if (info->optimize)
4830 unsigned long int nsyms = hashcodesp - hashcodes;
4831 size_t minsize;
4832 size_t maxsize;
4833 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4834 unsigned long int *counts ;
4835 bfd *dynobj = elf_hash_table (info)->dynobj;
4836 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4838 /* Possible optimization parameters: if we have NSYMS symbols we say
4839 that the hashing table must at least have NSYMS/4 and at most
4840 2*NSYMS buckets. */
4841 minsize = nsyms / 4;
4842 if (minsize == 0)
4843 minsize = 1;
4844 best_size = maxsize = nsyms * 2;
4846 /* Create array where we count the collisions in. We must use bfd_malloc
4847 since the size could be large. */
4848 amt = maxsize;
4849 amt *= sizeof (unsigned long int);
4850 counts = bfd_malloc (amt);
4851 if (counts == NULL)
4853 free (hashcodes);
4854 return 0;
4857 /* Compute the "optimal" size for the hash table. The criteria is a
4858 minimal chain length. The minor criteria is (of course) the size
4859 of the table. */
4860 for (i = minsize; i < maxsize; ++i)
4862 /* Walk through the array of hashcodes and count the collisions. */
4863 BFD_HOST_U_64_BIT max;
4864 unsigned long int j;
4865 unsigned long int fact;
4867 memset (counts, '\0', i * sizeof (unsigned long int));
4869 /* Determine how often each hash bucket is used. */
4870 for (j = 0; j < nsyms; ++j)
4871 ++counts[hashcodes[j] % i];
4873 /* For the weight function we need some information about the
4874 pagesize on the target. This is information need not be 100%
4875 accurate. Since this information is not available (so far) we
4876 define it here to a reasonable default value. If it is crucial
4877 to have a better value some day simply define this value. */
4878 # ifndef BFD_TARGET_PAGESIZE
4879 # define BFD_TARGET_PAGESIZE (4096)
4880 # endif
4882 /* We in any case need 2 + NSYMS entries for the size values and
4883 the chains. */
4884 max = (2 + nsyms) * (bed->s->arch_size / 8);
4886 # if 1
4887 /* Variant 1: optimize for short chains. We add the squares
4888 of all the chain lengths (which favors many small chain
4889 over a few long chains). */
4890 for (j = 0; j < i; ++j)
4891 max += counts[j] * counts[j];
4893 /* This adds penalties for the overall size of the table. */
4894 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4895 max *= fact * fact;
4896 # else
4897 /* Variant 2: Optimize a lot more for small table. Here we
4898 also add squares of the size but we also add penalties for
4899 empty slots (the +1 term). */
4900 for (j = 0; j < i; ++j)
4901 max += (1 + counts[j]) * (1 + counts[j]);
4903 /* The overall size of the table is considered, but not as
4904 strong as in variant 1, where it is squared. */
4905 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4906 max *= fact;
4907 # endif
4909 /* Compare with current best results. */
4910 if (max < best_chlen)
4912 best_chlen = max;
4913 best_size = i;
4917 free (counts);
4919 else
4920 #endif /* defined (BFD_HOST_U_64_BIT) */
4922 /* This is the fallback solution if no 64bit type is available or if we
4923 are not supposed to spend much time on optimizations. We select the
4924 bucket count using a fixed set of numbers. */
4925 for (i = 0; elf_buckets[i] != 0; i++)
4927 best_size = elf_buckets[i];
4928 if (dynsymcount < elf_buckets[i + 1])
4929 break;
4933 /* Free the arrays we needed. */
4934 free (hashcodes);
4936 return best_size;
4939 /* Set up the sizes and contents of the ELF dynamic sections. This is
4940 called by the ELF linker emulation before_allocation routine. We
4941 must set the sizes of the sections before the linker sets the
4942 addresses of the various sections. */
4944 bfd_boolean
4945 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4946 const char *soname,
4947 const char *rpath,
4948 const char *filter_shlib,
4949 const char * const *auxiliary_filters,
4950 struct bfd_link_info *info,
4951 asection **sinterpptr,
4952 struct bfd_elf_version_tree *verdefs)
4954 bfd_size_type soname_indx;
4955 bfd *dynobj;
4956 const struct elf_backend_data *bed;
4957 struct elf_assign_sym_version_info asvinfo;
4959 *sinterpptr = NULL;
4961 soname_indx = (bfd_size_type) -1;
4963 if (!is_elf_hash_table (info->hash))
4964 return TRUE;
4966 elf_tdata (output_bfd)->relro = info->relro;
4967 if (info->execstack)
4968 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4969 else if (info->noexecstack)
4970 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4971 else
4973 bfd *inputobj;
4974 asection *notesec = NULL;
4975 int exec = 0;
4977 for (inputobj = info->input_bfds;
4978 inputobj;
4979 inputobj = inputobj->link_next)
4981 asection *s;
4983 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
4984 continue;
4985 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
4986 if (s)
4988 if (s->flags & SEC_CODE)
4989 exec = PF_X;
4990 notesec = s;
4992 else
4993 exec = PF_X;
4995 if (notesec)
4997 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
4998 if (exec && info->relocatable
4999 && notesec->output_section != bfd_abs_section_ptr)
5000 notesec->output_section->flags |= SEC_CODE;
5004 /* Any syms created from now on start with -1 in
5005 got.refcount/offset and plt.refcount/offset. */
5006 elf_hash_table (info)->init_got_refcount
5007 = elf_hash_table (info)->init_got_offset;
5008 elf_hash_table (info)->init_plt_refcount
5009 = elf_hash_table (info)->init_plt_offset;
5011 /* The backend may have to create some sections regardless of whether
5012 we're dynamic or not. */
5013 bed = get_elf_backend_data (output_bfd);
5014 if (bed->elf_backend_always_size_sections
5015 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
5016 return FALSE;
5018 dynobj = elf_hash_table (info)->dynobj;
5020 /* If there were no dynamic objects in the link, there is nothing to
5021 do here. */
5022 if (dynobj == NULL)
5023 return TRUE;
5025 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5026 return FALSE;
5028 if (elf_hash_table (info)->dynamic_sections_created)
5030 struct elf_info_failed eif;
5031 struct elf_link_hash_entry *h;
5032 asection *dynstr;
5033 struct bfd_elf_version_tree *t;
5034 struct bfd_elf_version_expr *d;
5035 bfd_boolean all_defined;
5037 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5038 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5040 if (soname != NULL)
5042 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5043 soname, TRUE);
5044 if (soname_indx == (bfd_size_type) -1
5045 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5046 return FALSE;
5049 if (info->symbolic)
5051 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5052 return FALSE;
5053 info->flags |= DF_SYMBOLIC;
5056 if (rpath != NULL)
5058 bfd_size_type indx;
5060 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5061 TRUE);
5062 if (indx == (bfd_size_type) -1
5063 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5064 return FALSE;
5066 if (info->new_dtags)
5068 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5069 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5070 return FALSE;
5074 if (filter_shlib != NULL)
5076 bfd_size_type indx;
5078 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5079 filter_shlib, TRUE);
5080 if (indx == (bfd_size_type) -1
5081 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5082 return FALSE;
5085 if (auxiliary_filters != NULL)
5087 const char * const *p;
5089 for (p = auxiliary_filters; *p != NULL; p++)
5091 bfd_size_type indx;
5093 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5094 *p, TRUE);
5095 if (indx == (bfd_size_type) -1
5096 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5097 return FALSE;
5101 eif.info = info;
5102 eif.verdefs = verdefs;
5103 eif.failed = FALSE;
5105 /* If we are supposed to export all symbols into the dynamic symbol
5106 table (this is not the normal case), then do so. */
5107 if (info->export_dynamic)
5109 elf_link_hash_traverse (elf_hash_table (info),
5110 _bfd_elf_export_symbol,
5111 &eif);
5112 if (eif.failed)
5113 return FALSE;
5116 /* Make all global versions with definition. */
5117 for (t = verdefs; t != NULL; t = t->next)
5118 for (d = t->globals.list; d != NULL; d = d->next)
5119 if (!d->symver && d->symbol)
5121 const char *verstr, *name;
5122 size_t namelen, verlen, newlen;
5123 char *newname, *p;
5124 struct elf_link_hash_entry *newh;
5126 name = d->symbol;
5127 namelen = strlen (name);
5128 verstr = t->name;
5129 verlen = strlen (verstr);
5130 newlen = namelen + verlen + 3;
5132 newname = bfd_malloc (newlen);
5133 if (newname == NULL)
5134 return FALSE;
5135 memcpy (newname, name, namelen);
5137 /* Check the hidden versioned definition. */
5138 p = newname + namelen;
5139 *p++ = ELF_VER_CHR;
5140 memcpy (p, verstr, verlen + 1);
5141 newh = elf_link_hash_lookup (elf_hash_table (info),
5142 newname, FALSE, FALSE,
5143 FALSE);
5144 if (newh == NULL
5145 || (newh->root.type != bfd_link_hash_defined
5146 && newh->root.type != bfd_link_hash_defweak))
5148 /* Check the default versioned definition. */
5149 *p++ = ELF_VER_CHR;
5150 memcpy (p, verstr, verlen + 1);
5151 newh = elf_link_hash_lookup (elf_hash_table (info),
5152 newname, FALSE, FALSE,
5153 FALSE);
5155 free (newname);
5157 /* Mark this version if there is a definition and it is
5158 not defined in a shared object. */
5159 if (newh != NULL
5160 && !newh->def_dynamic
5161 && (newh->root.type == bfd_link_hash_defined
5162 || newh->root.type == bfd_link_hash_defweak))
5163 d->symver = 1;
5166 /* Attach all the symbols to their version information. */
5167 asvinfo.output_bfd = output_bfd;
5168 asvinfo.info = info;
5169 asvinfo.verdefs = verdefs;
5170 asvinfo.failed = FALSE;
5172 elf_link_hash_traverse (elf_hash_table (info),
5173 _bfd_elf_link_assign_sym_version,
5174 &asvinfo);
5175 if (asvinfo.failed)
5176 return FALSE;
5178 if (!info->allow_undefined_version)
5180 /* Check if all global versions have a definition. */
5181 all_defined = TRUE;
5182 for (t = verdefs; t != NULL; t = t->next)
5183 for (d = t->globals.list; d != NULL; d = d->next)
5184 if (!d->symver && !d->script)
5186 (*_bfd_error_handler)
5187 (_("%s: undefined version: %s"),
5188 d->pattern, t->name);
5189 all_defined = FALSE;
5192 if (!all_defined)
5194 bfd_set_error (bfd_error_bad_value);
5195 return FALSE;
5199 /* Find all symbols which were defined in a dynamic object and make
5200 the backend pick a reasonable value for them. */
5201 elf_link_hash_traverse (elf_hash_table (info),
5202 _bfd_elf_adjust_dynamic_symbol,
5203 &eif);
5204 if (eif.failed)
5205 return FALSE;
5207 /* Add some entries to the .dynamic section. We fill in some of the
5208 values later, in bfd_elf_final_link, but we must add the entries
5209 now so that we know the final size of the .dynamic section. */
5211 /* If there are initialization and/or finalization functions to
5212 call then add the corresponding DT_INIT/DT_FINI entries. */
5213 h = (info->init_function
5214 ? elf_link_hash_lookup (elf_hash_table (info),
5215 info->init_function, FALSE,
5216 FALSE, FALSE)
5217 : NULL);
5218 if (h != NULL
5219 && (h->ref_regular
5220 || h->def_regular))
5222 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5223 return FALSE;
5225 h = (info->fini_function
5226 ? elf_link_hash_lookup (elf_hash_table (info),
5227 info->fini_function, FALSE,
5228 FALSE, FALSE)
5229 : NULL);
5230 if (h != NULL
5231 && (h->ref_regular
5232 || h->def_regular))
5234 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5235 return FALSE;
5238 if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL)
5240 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5241 if (! info->executable)
5243 bfd *sub;
5244 asection *o;
5246 for (sub = info->input_bfds; sub != NULL;
5247 sub = sub->link_next)
5248 for (o = sub->sections; o != NULL; o = o->next)
5249 if (elf_section_data (o)->this_hdr.sh_type
5250 == SHT_PREINIT_ARRAY)
5252 (*_bfd_error_handler)
5253 (_("%B: .preinit_array section is not allowed in DSO"),
5254 sub);
5255 break;
5258 bfd_set_error (bfd_error_nonrepresentable_section);
5259 return FALSE;
5262 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5263 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5264 return FALSE;
5266 if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL)
5268 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5269 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5270 return FALSE;
5272 if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL)
5274 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5275 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5276 return FALSE;
5279 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5280 /* If .dynstr is excluded from the link, we don't want any of
5281 these tags. Strictly, we should be checking each section
5282 individually; This quick check covers for the case where
5283 someone does a /DISCARD/ : { *(*) }. */
5284 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5286 bfd_size_type strsize;
5288 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5289 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
5290 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5291 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5292 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5293 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5294 bed->s->sizeof_sym))
5295 return FALSE;
5299 /* The backend must work out the sizes of all the other dynamic
5300 sections. */
5301 if (bed->elf_backend_size_dynamic_sections
5302 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5303 return FALSE;
5305 if (elf_hash_table (info)->dynamic_sections_created)
5307 unsigned long section_sym_count;
5308 asection *s;
5310 /* Set up the version definition section. */
5311 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5312 BFD_ASSERT (s != NULL);
5314 /* We may have created additional version definitions if we are
5315 just linking a regular application. */
5316 verdefs = asvinfo.verdefs;
5318 /* Skip anonymous version tag. */
5319 if (verdefs != NULL && verdefs->vernum == 0)
5320 verdefs = verdefs->next;
5322 if (verdefs == NULL && !info->create_default_symver)
5323 s->flags |= SEC_EXCLUDE;
5324 else
5326 unsigned int cdefs;
5327 bfd_size_type size;
5328 struct bfd_elf_version_tree *t;
5329 bfd_byte *p;
5330 Elf_Internal_Verdef def;
5331 Elf_Internal_Verdaux defaux;
5332 struct bfd_link_hash_entry *bh;
5333 struct elf_link_hash_entry *h;
5334 const char *name;
5336 cdefs = 0;
5337 size = 0;
5339 /* Make space for the base version. */
5340 size += sizeof (Elf_External_Verdef);
5341 size += sizeof (Elf_External_Verdaux);
5342 ++cdefs;
5344 /* Make space for the default version. */
5345 if (info->create_default_symver)
5347 size += sizeof (Elf_External_Verdef);
5348 ++cdefs;
5351 for (t = verdefs; t != NULL; t = t->next)
5353 struct bfd_elf_version_deps *n;
5355 size += sizeof (Elf_External_Verdef);
5356 size += sizeof (Elf_External_Verdaux);
5357 ++cdefs;
5359 for (n = t->deps; n != NULL; n = n->next)
5360 size += sizeof (Elf_External_Verdaux);
5363 s->size = size;
5364 s->contents = bfd_alloc (output_bfd, s->size);
5365 if (s->contents == NULL && s->size != 0)
5366 return FALSE;
5368 /* Fill in the version definition section. */
5370 p = s->contents;
5372 def.vd_version = VER_DEF_CURRENT;
5373 def.vd_flags = VER_FLG_BASE;
5374 def.vd_ndx = 1;
5375 def.vd_cnt = 1;
5376 if (info->create_default_symver)
5378 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5379 def.vd_next = sizeof (Elf_External_Verdef);
5381 else
5383 def.vd_aux = sizeof (Elf_External_Verdef);
5384 def.vd_next = (sizeof (Elf_External_Verdef)
5385 + sizeof (Elf_External_Verdaux));
5388 if (soname_indx != (bfd_size_type) -1)
5390 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5391 soname_indx);
5392 def.vd_hash = bfd_elf_hash (soname);
5393 defaux.vda_name = soname_indx;
5394 name = soname;
5396 else
5398 bfd_size_type indx;
5400 name = lbasename (output_bfd->filename);
5401 def.vd_hash = bfd_elf_hash (name);
5402 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5403 name, FALSE);
5404 if (indx == (bfd_size_type) -1)
5405 return FALSE;
5406 defaux.vda_name = indx;
5408 defaux.vda_next = 0;
5410 _bfd_elf_swap_verdef_out (output_bfd, &def,
5411 (Elf_External_Verdef *) p);
5412 p += sizeof (Elf_External_Verdef);
5413 if (info->create_default_symver)
5415 /* Add a symbol representing this version. */
5416 bh = NULL;
5417 if (! (_bfd_generic_link_add_one_symbol
5418 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5419 0, NULL, FALSE,
5420 get_elf_backend_data (dynobj)->collect, &bh)))
5421 return FALSE;
5422 h = (struct elf_link_hash_entry *) bh;
5423 h->non_elf = 0;
5424 h->def_regular = 1;
5425 h->type = STT_OBJECT;
5426 h->verinfo.vertree = NULL;
5428 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5429 return FALSE;
5431 /* Create a duplicate of the base version with the same
5432 aux block, but different flags. */
5433 def.vd_flags = 0;
5434 def.vd_ndx = 2;
5435 def.vd_aux = sizeof (Elf_External_Verdef);
5436 if (verdefs)
5437 def.vd_next = (sizeof (Elf_External_Verdef)
5438 + sizeof (Elf_External_Verdaux));
5439 else
5440 def.vd_next = 0;
5441 _bfd_elf_swap_verdef_out (output_bfd, &def,
5442 (Elf_External_Verdef *) p);
5443 p += sizeof (Elf_External_Verdef);
5445 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5446 (Elf_External_Verdaux *) p);
5447 p += sizeof (Elf_External_Verdaux);
5449 for (t = verdefs; t != NULL; t = t->next)
5451 unsigned int cdeps;
5452 struct bfd_elf_version_deps *n;
5454 cdeps = 0;
5455 for (n = t->deps; n != NULL; n = n->next)
5456 ++cdeps;
5458 /* Add a symbol representing this version. */
5459 bh = NULL;
5460 if (! (_bfd_generic_link_add_one_symbol
5461 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5462 0, NULL, FALSE,
5463 get_elf_backend_data (dynobj)->collect, &bh)))
5464 return FALSE;
5465 h = (struct elf_link_hash_entry *) bh;
5466 h->non_elf = 0;
5467 h->def_regular = 1;
5468 h->type = STT_OBJECT;
5469 h->verinfo.vertree = t;
5471 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5472 return FALSE;
5474 def.vd_version = VER_DEF_CURRENT;
5475 def.vd_flags = 0;
5476 if (t->globals.list == NULL
5477 && t->locals.list == NULL
5478 && ! t->used)
5479 def.vd_flags |= VER_FLG_WEAK;
5480 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5481 def.vd_cnt = cdeps + 1;
5482 def.vd_hash = bfd_elf_hash (t->name);
5483 def.vd_aux = sizeof (Elf_External_Verdef);
5484 def.vd_next = 0;
5485 if (t->next != NULL)
5486 def.vd_next = (sizeof (Elf_External_Verdef)
5487 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5489 _bfd_elf_swap_verdef_out (output_bfd, &def,
5490 (Elf_External_Verdef *) p);
5491 p += sizeof (Elf_External_Verdef);
5493 defaux.vda_name = h->dynstr_index;
5494 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5495 h->dynstr_index);
5496 defaux.vda_next = 0;
5497 if (t->deps != NULL)
5498 defaux.vda_next = sizeof (Elf_External_Verdaux);
5499 t->name_indx = defaux.vda_name;
5501 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5502 (Elf_External_Verdaux *) p);
5503 p += sizeof (Elf_External_Verdaux);
5505 for (n = t->deps; n != NULL; n = n->next)
5507 if (n->version_needed == NULL)
5509 /* This can happen if there was an error in the
5510 version script. */
5511 defaux.vda_name = 0;
5513 else
5515 defaux.vda_name = n->version_needed->name_indx;
5516 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5517 defaux.vda_name);
5519 if (n->next == NULL)
5520 defaux.vda_next = 0;
5521 else
5522 defaux.vda_next = sizeof (Elf_External_Verdaux);
5524 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5525 (Elf_External_Verdaux *) p);
5526 p += sizeof (Elf_External_Verdaux);
5530 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5531 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5532 return FALSE;
5534 elf_tdata (output_bfd)->cverdefs = cdefs;
5537 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5539 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5540 return FALSE;
5542 else if (info->flags & DF_BIND_NOW)
5544 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5545 return FALSE;
5548 if (info->flags_1)
5550 if (info->executable)
5551 info->flags_1 &= ~ (DF_1_INITFIRST
5552 | DF_1_NODELETE
5553 | DF_1_NOOPEN);
5554 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5555 return FALSE;
5558 /* Work out the size of the version reference section. */
5560 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5561 BFD_ASSERT (s != NULL);
5563 struct elf_find_verdep_info sinfo;
5565 sinfo.output_bfd = output_bfd;
5566 sinfo.info = info;
5567 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5568 if (sinfo.vers == 0)
5569 sinfo.vers = 1;
5570 sinfo.failed = FALSE;
5572 elf_link_hash_traverse (elf_hash_table (info),
5573 _bfd_elf_link_find_version_dependencies,
5574 &sinfo);
5576 if (elf_tdata (output_bfd)->verref == NULL)
5577 s->flags |= SEC_EXCLUDE;
5578 else
5580 Elf_Internal_Verneed *t;
5581 unsigned int size;
5582 unsigned int crefs;
5583 bfd_byte *p;
5585 /* Build the version definition section. */
5586 size = 0;
5587 crefs = 0;
5588 for (t = elf_tdata (output_bfd)->verref;
5589 t != NULL;
5590 t = t->vn_nextref)
5592 Elf_Internal_Vernaux *a;
5594 size += sizeof (Elf_External_Verneed);
5595 ++crefs;
5596 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5597 size += sizeof (Elf_External_Vernaux);
5600 s->size = size;
5601 s->contents = bfd_alloc (output_bfd, s->size);
5602 if (s->contents == NULL)
5603 return FALSE;
5605 p = s->contents;
5606 for (t = elf_tdata (output_bfd)->verref;
5607 t != NULL;
5608 t = t->vn_nextref)
5610 unsigned int caux;
5611 Elf_Internal_Vernaux *a;
5612 bfd_size_type indx;
5614 caux = 0;
5615 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5616 ++caux;
5618 t->vn_version = VER_NEED_CURRENT;
5619 t->vn_cnt = caux;
5620 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5621 elf_dt_name (t->vn_bfd) != NULL
5622 ? elf_dt_name (t->vn_bfd)
5623 : lbasename (t->vn_bfd->filename),
5624 FALSE);
5625 if (indx == (bfd_size_type) -1)
5626 return FALSE;
5627 t->vn_file = indx;
5628 t->vn_aux = sizeof (Elf_External_Verneed);
5629 if (t->vn_nextref == NULL)
5630 t->vn_next = 0;
5631 else
5632 t->vn_next = (sizeof (Elf_External_Verneed)
5633 + caux * sizeof (Elf_External_Vernaux));
5635 _bfd_elf_swap_verneed_out (output_bfd, t,
5636 (Elf_External_Verneed *) p);
5637 p += sizeof (Elf_External_Verneed);
5639 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5641 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5642 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5643 a->vna_nodename, FALSE);
5644 if (indx == (bfd_size_type) -1)
5645 return FALSE;
5646 a->vna_name = indx;
5647 if (a->vna_nextptr == NULL)
5648 a->vna_next = 0;
5649 else
5650 a->vna_next = sizeof (Elf_External_Vernaux);
5652 _bfd_elf_swap_vernaux_out (output_bfd, a,
5653 (Elf_External_Vernaux *) p);
5654 p += sizeof (Elf_External_Vernaux);
5658 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5659 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5660 return FALSE;
5662 elf_tdata (output_bfd)->cverrefs = crefs;
5666 if ((elf_tdata (output_bfd)->cverrefs == 0
5667 && elf_tdata (output_bfd)->cverdefs == 0)
5668 || _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5669 &section_sym_count) == 0)
5671 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5672 s->flags |= SEC_EXCLUDE;
5675 return TRUE;
5678 bfd_boolean
5679 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
5681 if (!is_elf_hash_table (info->hash))
5682 return TRUE;
5684 if (elf_hash_table (info)->dynamic_sections_created)
5686 bfd *dynobj;
5687 const struct elf_backend_data *bed;
5688 asection *s;
5689 bfd_size_type dynsymcount;
5690 unsigned long section_sym_count;
5691 size_t bucketcount = 0;
5692 size_t hash_entry_size;
5693 unsigned int dtagcount;
5695 dynobj = elf_hash_table (info)->dynobj;
5697 /* Assign dynsym indicies. In a shared library we generate a
5698 section symbol for each output section, which come first.
5699 Next come all of the back-end allocated local dynamic syms,
5700 followed by the rest of the global symbols. */
5702 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5703 &section_sym_count);
5705 /* Work out the size of the symbol version section. */
5706 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5707 BFD_ASSERT (s != NULL);
5708 if (dynsymcount != 0
5709 && (s->flags & SEC_EXCLUDE) == 0)
5711 s->size = dynsymcount * sizeof (Elf_External_Versym);
5712 s->contents = bfd_zalloc (output_bfd, s->size);
5713 if (s->contents == NULL)
5714 return FALSE;
5716 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5717 return FALSE;
5720 /* Set the size of the .dynsym and .hash sections. We counted
5721 the number of dynamic symbols in elf_link_add_object_symbols.
5722 We will build the contents of .dynsym and .hash when we build
5723 the final symbol table, because until then we do not know the
5724 correct value to give the symbols. We built the .dynstr
5725 section as we went along in elf_link_add_object_symbols. */
5726 s = bfd_get_section_by_name (dynobj, ".dynsym");
5727 BFD_ASSERT (s != NULL);
5728 bed = get_elf_backend_data (output_bfd);
5729 s->size = dynsymcount * bed->s->sizeof_sym;
5731 if (dynsymcount != 0)
5733 s->contents = bfd_alloc (output_bfd, s->size);
5734 if (s->contents == NULL)
5735 return FALSE;
5737 /* The first entry in .dynsym is a dummy symbol.
5738 Clear all the section syms, in case we don't output them all. */
5739 ++section_sym_count;
5740 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
5743 /* Compute the size of the hashing table. As a side effect this
5744 computes the hash values for all the names we export. */
5745 bucketcount = compute_bucket_count (info);
5747 s = bfd_get_section_by_name (dynobj, ".hash");
5748 BFD_ASSERT (s != NULL);
5749 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5750 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5751 s->contents = bfd_zalloc (output_bfd, s->size);
5752 if (s->contents == NULL)
5753 return FALSE;
5755 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5756 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5757 s->contents + hash_entry_size);
5759 elf_hash_table (info)->bucketcount = bucketcount;
5761 s = bfd_get_section_by_name (dynobj, ".dynstr");
5762 BFD_ASSERT (s != NULL);
5764 elf_finalize_dynstr (output_bfd, info);
5766 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5768 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5769 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5770 return FALSE;
5773 return TRUE;
5776 /* Final phase of ELF linker. */
5778 /* A structure we use to avoid passing large numbers of arguments. */
5780 struct elf_final_link_info
5782 /* General link information. */
5783 struct bfd_link_info *info;
5784 /* Output BFD. */
5785 bfd *output_bfd;
5786 /* Symbol string table. */
5787 struct bfd_strtab_hash *symstrtab;
5788 /* .dynsym section. */
5789 asection *dynsym_sec;
5790 /* .hash section. */
5791 asection *hash_sec;
5792 /* symbol version section (.gnu.version). */
5793 asection *symver_sec;
5794 /* Buffer large enough to hold contents of any section. */
5795 bfd_byte *contents;
5796 /* Buffer large enough to hold external relocs of any section. */
5797 void *external_relocs;
5798 /* Buffer large enough to hold internal relocs of any section. */
5799 Elf_Internal_Rela *internal_relocs;
5800 /* Buffer large enough to hold external local symbols of any input
5801 BFD. */
5802 bfd_byte *external_syms;
5803 /* And a buffer for symbol section indices. */
5804 Elf_External_Sym_Shndx *locsym_shndx;
5805 /* Buffer large enough to hold internal local symbols of any input
5806 BFD. */
5807 Elf_Internal_Sym *internal_syms;
5808 /* Array large enough to hold a symbol index for each local symbol
5809 of any input BFD. */
5810 long *indices;
5811 /* Array large enough to hold a section pointer for each local
5812 symbol of any input BFD. */
5813 asection **sections;
5814 /* Buffer to hold swapped out symbols. */
5815 bfd_byte *symbuf;
5816 /* And one for symbol section indices. */
5817 Elf_External_Sym_Shndx *symshndxbuf;
5818 /* Number of swapped out symbols in buffer. */
5819 size_t symbuf_count;
5820 /* Number of symbols which fit in symbuf. */
5821 size_t symbuf_size;
5822 /* And same for symshndxbuf. */
5823 size_t shndxbuf_size;
5826 /* This struct is used to pass information to elf_link_output_extsym. */
5828 struct elf_outext_info
5830 bfd_boolean failed;
5831 bfd_boolean localsyms;
5832 struct elf_final_link_info *finfo;
5835 /* When performing a relocatable link, the input relocations are
5836 preserved. But, if they reference global symbols, the indices
5837 referenced must be updated. Update all the relocations in
5838 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5840 static void
5841 elf_link_adjust_relocs (bfd *abfd,
5842 Elf_Internal_Shdr *rel_hdr,
5843 unsigned int count,
5844 struct elf_link_hash_entry **rel_hash)
5846 unsigned int i;
5847 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5848 bfd_byte *erela;
5849 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5850 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5851 bfd_vma r_type_mask;
5852 int r_sym_shift;
5854 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5856 swap_in = bed->s->swap_reloc_in;
5857 swap_out = bed->s->swap_reloc_out;
5859 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5861 swap_in = bed->s->swap_reloca_in;
5862 swap_out = bed->s->swap_reloca_out;
5864 else
5865 abort ();
5867 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5868 abort ();
5870 if (bed->s->arch_size == 32)
5872 r_type_mask = 0xff;
5873 r_sym_shift = 8;
5875 else
5877 r_type_mask = 0xffffffff;
5878 r_sym_shift = 32;
5881 erela = rel_hdr->contents;
5882 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5884 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5885 unsigned int j;
5887 if (*rel_hash == NULL)
5888 continue;
5890 BFD_ASSERT ((*rel_hash)->indx >= 0);
5892 (*swap_in) (abfd, erela, irela);
5893 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5894 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5895 | (irela[j].r_info & r_type_mask));
5896 (*swap_out) (abfd, irela, erela);
5900 struct elf_link_sort_rela
5902 union {
5903 bfd_vma offset;
5904 bfd_vma sym_mask;
5905 } u;
5906 enum elf_reloc_type_class type;
5907 /* We use this as an array of size int_rels_per_ext_rel. */
5908 Elf_Internal_Rela rela[1];
5911 static int
5912 elf_link_sort_cmp1 (const void *A, const void *B)
5914 const struct elf_link_sort_rela *a = A;
5915 const struct elf_link_sort_rela *b = B;
5916 int relativea, relativeb;
5918 relativea = a->type == reloc_class_relative;
5919 relativeb = b->type == reloc_class_relative;
5921 if (relativea < relativeb)
5922 return 1;
5923 if (relativea > relativeb)
5924 return -1;
5925 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5926 return -1;
5927 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5928 return 1;
5929 if (a->rela->r_offset < b->rela->r_offset)
5930 return -1;
5931 if (a->rela->r_offset > b->rela->r_offset)
5932 return 1;
5933 return 0;
5936 static int
5937 elf_link_sort_cmp2 (const void *A, const void *B)
5939 const struct elf_link_sort_rela *a = A;
5940 const struct elf_link_sort_rela *b = B;
5941 int copya, copyb;
5943 if (a->u.offset < b->u.offset)
5944 return -1;
5945 if (a->u.offset > b->u.offset)
5946 return 1;
5947 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5948 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5949 if (copya < copyb)
5950 return -1;
5951 if (copya > copyb)
5952 return 1;
5953 if (a->rela->r_offset < b->rela->r_offset)
5954 return -1;
5955 if (a->rela->r_offset > b->rela->r_offset)
5956 return 1;
5957 return 0;
5960 static size_t
5961 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5963 asection *reldyn;
5964 bfd_size_type count, size;
5965 size_t i, ret, sort_elt, ext_size;
5966 bfd_byte *sort, *s_non_relative, *p;
5967 struct elf_link_sort_rela *sq;
5968 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5969 int i2e = bed->s->int_rels_per_ext_rel;
5970 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5971 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5972 struct bfd_link_order *lo;
5973 bfd_vma r_sym_mask;
5975 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5976 if (reldyn == NULL || reldyn->size == 0)
5978 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
5979 if (reldyn == NULL || reldyn->size == 0)
5980 return 0;
5981 ext_size = bed->s->sizeof_rel;
5982 swap_in = bed->s->swap_reloc_in;
5983 swap_out = bed->s->swap_reloc_out;
5985 else
5987 ext_size = bed->s->sizeof_rela;
5988 swap_in = bed->s->swap_reloca_in;
5989 swap_out = bed->s->swap_reloca_out;
5991 count = reldyn->size / ext_size;
5993 size = 0;
5994 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
5995 if (lo->type == bfd_indirect_link_order)
5997 asection *o = lo->u.indirect.section;
5998 size += o->size;
6001 if (size != reldyn->size)
6002 return 0;
6004 sort_elt = (sizeof (struct elf_link_sort_rela)
6005 + (i2e - 1) * sizeof (Elf_Internal_Rela));
6006 sort = bfd_zmalloc (sort_elt * count);
6007 if (sort == NULL)
6009 (*info->callbacks->warning)
6010 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
6011 return 0;
6014 if (bed->s->arch_size == 32)
6015 r_sym_mask = ~(bfd_vma) 0xff;
6016 else
6017 r_sym_mask = ~(bfd_vma) 0xffffffff;
6019 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6020 if (lo->type == bfd_indirect_link_order)
6022 bfd_byte *erel, *erelend;
6023 asection *o = lo->u.indirect.section;
6025 if (o->contents == NULL && o->size != 0)
6027 /* This is a reloc section that is being handled as a normal
6028 section. See bfd_section_from_shdr. We can't combine
6029 relocs in this case. */
6030 free (sort);
6031 return 0;
6033 erel = o->contents;
6034 erelend = o->contents + o->size;
6035 p = sort + o->output_offset / ext_size * sort_elt;
6036 while (erel < erelend)
6038 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6039 (*swap_in) (abfd, erel, s->rela);
6040 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
6041 s->u.sym_mask = r_sym_mask;
6042 p += sort_elt;
6043 erel += ext_size;
6047 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
6049 for (i = 0, p = sort; i < count; i++, p += sort_elt)
6051 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6052 if (s->type != reloc_class_relative)
6053 break;
6055 ret = i;
6056 s_non_relative = p;
6058 sq = (struct elf_link_sort_rela *) s_non_relative;
6059 for (; i < count; i++, p += sort_elt)
6061 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
6062 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
6063 sq = sp;
6064 sp->u.offset = sq->rela->r_offset;
6067 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
6069 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6070 if (lo->type == bfd_indirect_link_order)
6072 bfd_byte *erel, *erelend;
6073 asection *o = lo->u.indirect.section;
6075 erel = o->contents;
6076 erelend = o->contents + o->size;
6077 p = sort + o->output_offset / ext_size * sort_elt;
6078 while (erel < erelend)
6080 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6081 (*swap_out) (abfd, s->rela, erel);
6082 p += sort_elt;
6083 erel += ext_size;
6087 free (sort);
6088 *psec = reldyn;
6089 return ret;
6092 /* Flush the output symbols to the file. */
6094 static bfd_boolean
6095 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
6096 const struct elf_backend_data *bed)
6098 if (finfo->symbuf_count > 0)
6100 Elf_Internal_Shdr *hdr;
6101 file_ptr pos;
6102 bfd_size_type amt;
6104 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6105 pos = hdr->sh_offset + hdr->sh_size;
6106 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6107 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6108 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6109 return FALSE;
6111 hdr->sh_size += amt;
6112 finfo->symbuf_count = 0;
6115 return TRUE;
6118 /* Add a symbol to the output symbol table. */
6120 static bfd_boolean
6121 elf_link_output_sym (struct elf_final_link_info *finfo,
6122 const char *name,
6123 Elf_Internal_Sym *elfsym,
6124 asection *input_sec,
6125 struct elf_link_hash_entry *h)
6127 bfd_byte *dest;
6128 Elf_External_Sym_Shndx *destshndx;
6129 bfd_boolean (*output_symbol_hook)
6130 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6131 struct elf_link_hash_entry *);
6132 const struct elf_backend_data *bed;
6134 bed = get_elf_backend_data (finfo->output_bfd);
6135 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6136 if (output_symbol_hook != NULL)
6138 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6139 return FALSE;
6142 if (name == NULL || *name == '\0')
6143 elfsym->st_name = 0;
6144 else if (input_sec->flags & SEC_EXCLUDE)
6145 elfsym->st_name = 0;
6146 else
6148 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6149 name, TRUE, FALSE);
6150 if (elfsym->st_name == (unsigned long) -1)
6151 return FALSE;
6154 if (finfo->symbuf_count >= finfo->symbuf_size)
6156 if (! elf_link_flush_output_syms (finfo, bed))
6157 return FALSE;
6160 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6161 destshndx = finfo->symshndxbuf;
6162 if (destshndx != NULL)
6164 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6166 bfd_size_type amt;
6168 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6169 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6170 if (destshndx == NULL)
6171 return FALSE;
6172 memset ((char *) destshndx + amt, 0, amt);
6173 finfo->shndxbuf_size *= 2;
6175 destshndx += bfd_get_symcount (finfo->output_bfd);
6178 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6179 finfo->symbuf_count += 1;
6180 bfd_get_symcount (finfo->output_bfd) += 1;
6182 return TRUE;
6185 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6186 allowing an unsatisfied unversioned symbol in the DSO to match a
6187 versioned symbol that would normally require an explicit version.
6188 We also handle the case that a DSO references a hidden symbol
6189 which may be satisfied by a versioned symbol in another DSO. */
6191 static bfd_boolean
6192 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6193 const struct elf_backend_data *bed,
6194 struct elf_link_hash_entry *h)
6196 bfd *abfd;
6197 struct elf_link_loaded_list *loaded;
6199 if (!is_elf_hash_table (info->hash))
6200 return FALSE;
6202 switch (h->root.type)
6204 default:
6205 abfd = NULL;
6206 break;
6208 case bfd_link_hash_undefined:
6209 case bfd_link_hash_undefweak:
6210 abfd = h->root.u.undef.abfd;
6211 if ((abfd->flags & DYNAMIC) == 0
6212 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6213 return FALSE;
6214 break;
6216 case bfd_link_hash_defined:
6217 case bfd_link_hash_defweak:
6218 abfd = h->root.u.def.section->owner;
6219 break;
6221 case bfd_link_hash_common:
6222 abfd = h->root.u.c.p->section->owner;
6223 break;
6225 BFD_ASSERT (abfd != NULL);
6227 for (loaded = elf_hash_table (info)->loaded;
6228 loaded != NULL;
6229 loaded = loaded->next)
6231 bfd *input;
6232 Elf_Internal_Shdr *hdr;
6233 bfd_size_type symcount;
6234 bfd_size_type extsymcount;
6235 bfd_size_type extsymoff;
6236 Elf_Internal_Shdr *versymhdr;
6237 Elf_Internal_Sym *isym;
6238 Elf_Internal_Sym *isymend;
6239 Elf_Internal_Sym *isymbuf;
6240 Elf_External_Versym *ever;
6241 Elf_External_Versym *extversym;
6243 input = loaded->abfd;
6245 /* We check each DSO for a possible hidden versioned definition. */
6246 if (input == abfd
6247 || (input->flags & DYNAMIC) == 0
6248 || elf_dynversym (input) == 0)
6249 continue;
6251 hdr = &elf_tdata (input)->dynsymtab_hdr;
6253 symcount = hdr->sh_size / bed->s->sizeof_sym;
6254 if (elf_bad_symtab (input))
6256 extsymcount = symcount;
6257 extsymoff = 0;
6259 else
6261 extsymcount = symcount - hdr->sh_info;
6262 extsymoff = hdr->sh_info;
6265 if (extsymcount == 0)
6266 continue;
6268 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6269 NULL, NULL, NULL);
6270 if (isymbuf == NULL)
6271 return FALSE;
6273 /* Read in any version definitions. */
6274 versymhdr = &elf_tdata (input)->dynversym_hdr;
6275 extversym = bfd_malloc (versymhdr->sh_size);
6276 if (extversym == NULL)
6277 goto error_ret;
6279 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6280 || (bfd_bread (extversym, versymhdr->sh_size, input)
6281 != versymhdr->sh_size))
6283 free (extversym);
6284 error_ret:
6285 free (isymbuf);
6286 return FALSE;
6289 ever = extversym + extsymoff;
6290 isymend = isymbuf + extsymcount;
6291 for (isym = isymbuf; isym < isymend; isym++, ever++)
6293 const char *name;
6294 Elf_Internal_Versym iver;
6295 unsigned short version_index;
6297 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6298 || isym->st_shndx == SHN_UNDEF)
6299 continue;
6301 name = bfd_elf_string_from_elf_section (input,
6302 hdr->sh_link,
6303 isym->st_name);
6304 if (strcmp (name, h->root.root.string) != 0)
6305 continue;
6307 _bfd_elf_swap_versym_in (input, ever, &iver);
6309 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6311 /* If we have a non-hidden versioned sym, then it should
6312 have provided a definition for the undefined sym. */
6313 abort ();
6316 version_index = iver.vs_vers & VERSYM_VERSION;
6317 if (version_index == 1 || version_index == 2)
6319 /* This is the base or first version. We can use it. */
6320 free (extversym);
6321 free (isymbuf);
6322 return TRUE;
6326 free (extversym);
6327 free (isymbuf);
6330 return FALSE;
6333 /* Add an external symbol to the symbol table. This is called from
6334 the hash table traversal routine. When generating a shared object,
6335 we go through the symbol table twice. The first time we output
6336 anything that might have been forced to local scope in a version
6337 script. The second time we output the symbols that are still
6338 global symbols. */
6340 static bfd_boolean
6341 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6343 struct elf_outext_info *eoinfo = data;
6344 struct elf_final_link_info *finfo = eoinfo->finfo;
6345 bfd_boolean strip;
6346 Elf_Internal_Sym sym;
6347 asection *input_sec;
6348 const struct elf_backend_data *bed;
6350 if (h->root.type == bfd_link_hash_warning)
6352 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6353 if (h->root.type == bfd_link_hash_new)
6354 return TRUE;
6357 /* Decide whether to output this symbol in this pass. */
6358 if (eoinfo->localsyms)
6360 if (!h->forced_local)
6361 return TRUE;
6363 else
6365 if (h->forced_local)
6366 return TRUE;
6369 bed = get_elf_backend_data (finfo->output_bfd);
6371 /* If we have an undefined symbol reference here then it must have
6372 come from a shared library that is being linked in. (Undefined
6373 references in regular files have already been handled). If we
6374 are reporting errors for this situation then do so now. */
6375 if (h->root.type == bfd_link_hash_undefined
6376 && h->ref_dynamic
6377 && !h->ref_regular
6378 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6379 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6381 if (! ((*finfo->info->callbacks->undefined_symbol)
6382 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6383 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6385 eoinfo->failed = TRUE;
6386 return FALSE;
6390 /* We should also warn if a forced local symbol is referenced from
6391 shared libraries. */
6392 if (! finfo->info->relocatable
6393 && (! finfo->info->shared)
6394 && h->forced_local
6395 && h->ref_dynamic
6396 && !h->dynamic_def
6397 && !h->dynamic_weak
6398 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6400 (*_bfd_error_handler)
6401 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6402 finfo->output_bfd,
6403 h->root.u.def.section == bfd_abs_section_ptr
6404 ? finfo->output_bfd : h->root.u.def.section->owner,
6405 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6406 ? "internal"
6407 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6408 ? "hidden" : "local",
6409 h->root.root.string);
6410 eoinfo->failed = TRUE;
6411 return FALSE;
6414 /* We don't want to output symbols that have never been mentioned by
6415 a regular file, or that we have been told to strip. However, if
6416 h->indx is set to -2, the symbol is used by a reloc and we must
6417 output it. */
6418 if (h->indx == -2)
6419 strip = FALSE;
6420 else if ((h->def_dynamic
6421 || h->ref_dynamic
6422 || h->root.type == bfd_link_hash_new)
6423 && !h->def_regular
6424 && !h->ref_regular)
6425 strip = TRUE;
6426 else if (finfo->info->strip == strip_all)
6427 strip = TRUE;
6428 else if (finfo->info->strip == strip_some
6429 && bfd_hash_lookup (finfo->info->keep_hash,
6430 h->root.root.string, FALSE, FALSE) == NULL)
6431 strip = TRUE;
6432 else if (finfo->info->strip_discarded
6433 && (h->root.type == bfd_link_hash_defined
6434 || h->root.type == bfd_link_hash_defweak)
6435 && elf_discarded_section (h->root.u.def.section))
6436 strip = TRUE;
6437 else
6438 strip = FALSE;
6440 /* If we're stripping it, and it's not a dynamic symbol, there's
6441 nothing else to do unless it is a forced local symbol. */
6442 if (strip
6443 && h->dynindx == -1
6444 && !h->forced_local)
6445 return TRUE;
6447 sym.st_value = 0;
6448 sym.st_size = h->size;
6449 sym.st_other = h->other;
6450 if (h->forced_local)
6451 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6452 else if (h->root.type == bfd_link_hash_undefweak
6453 || h->root.type == bfd_link_hash_defweak)
6454 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6455 else
6456 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6458 switch (h->root.type)
6460 default:
6461 case bfd_link_hash_new:
6462 case bfd_link_hash_warning:
6463 abort ();
6464 return FALSE;
6466 case bfd_link_hash_undefined:
6467 case bfd_link_hash_undefweak:
6468 input_sec = bfd_und_section_ptr;
6469 sym.st_shndx = SHN_UNDEF;
6470 break;
6472 case bfd_link_hash_defined:
6473 case bfd_link_hash_defweak:
6475 input_sec = h->root.u.def.section;
6476 if (input_sec->output_section != NULL)
6478 sym.st_shndx =
6479 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6480 input_sec->output_section);
6481 if (sym.st_shndx == SHN_BAD)
6483 (*_bfd_error_handler)
6484 (_("%B: could not find output section %A for input section %A"),
6485 finfo->output_bfd, input_sec->output_section, input_sec);
6486 eoinfo->failed = TRUE;
6487 return FALSE;
6490 /* ELF symbols in relocatable files are section relative,
6491 but in nonrelocatable files they are virtual
6492 addresses. */
6493 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6494 if (! finfo->info->relocatable)
6496 sym.st_value += input_sec->output_section->vma;
6497 if (h->type == STT_TLS)
6499 /* STT_TLS symbols are relative to PT_TLS segment
6500 base. */
6501 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6502 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6506 else
6508 BFD_ASSERT (input_sec->owner == NULL
6509 || (input_sec->owner->flags & DYNAMIC) != 0);
6510 sym.st_shndx = SHN_UNDEF;
6511 input_sec = bfd_und_section_ptr;
6514 break;
6516 case bfd_link_hash_common:
6517 input_sec = h->root.u.c.p->section;
6518 sym.st_shndx = bed->common_section_index (input_sec);
6519 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6520 break;
6522 case bfd_link_hash_indirect:
6523 /* These symbols are created by symbol versioning. They point
6524 to the decorated version of the name. For example, if the
6525 symbol foo@@GNU_1.2 is the default, which should be used when
6526 foo is used with no version, then we add an indirect symbol
6527 foo which points to foo@@GNU_1.2. We ignore these symbols,
6528 since the indirected symbol is already in the hash table. */
6529 return TRUE;
6532 /* Give the processor backend a chance to tweak the symbol value,
6533 and also to finish up anything that needs to be done for this
6534 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6535 forced local syms when non-shared is due to a historical quirk. */
6536 if ((h->dynindx != -1
6537 || h->forced_local)
6538 && ((finfo->info->shared
6539 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6540 || h->root.type != bfd_link_hash_undefweak))
6541 || !h->forced_local)
6542 && elf_hash_table (finfo->info)->dynamic_sections_created)
6544 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6545 (finfo->output_bfd, finfo->info, h, &sym)))
6547 eoinfo->failed = TRUE;
6548 return FALSE;
6552 /* If we are marking the symbol as undefined, and there are no
6553 non-weak references to this symbol from a regular object, then
6554 mark the symbol as weak undefined; if there are non-weak
6555 references, mark the symbol as strong. We can't do this earlier,
6556 because it might not be marked as undefined until the
6557 finish_dynamic_symbol routine gets through with it. */
6558 if (sym.st_shndx == SHN_UNDEF
6559 && h->ref_regular
6560 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6561 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6563 int bindtype;
6565 if (h->ref_regular_nonweak)
6566 bindtype = STB_GLOBAL;
6567 else
6568 bindtype = STB_WEAK;
6569 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6572 /* If a non-weak symbol with non-default visibility is not defined
6573 locally, it is a fatal error. */
6574 if (! finfo->info->relocatable
6575 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6576 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6577 && h->root.type == bfd_link_hash_undefined
6578 && !h->def_regular)
6580 (*_bfd_error_handler)
6581 (_("%B: %s symbol `%s' isn't defined"),
6582 finfo->output_bfd,
6583 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6584 ? "protected"
6585 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6586 ? "internal" : "hidden",
6587 h->root.root.string);
6588 eoinfo->failed = TRUE;
6589 return FALSE;
6592 /* If this symbol should be put in the .dynsym section, then put it
6593 there now. We already know the symbol index. We also fill in
6594 the entry in the .hash section. */
6595 if (h->dynindx != -1
6596 && elf_hash_table (finfo->info)->dynamic_sections_created)
6598 size_t bucketcount;
6599 size_t bucket;
6600 size_t hash_entry_size;
6601 bfd_byte *bucketpos;
6602 bfd_vma chain;
6603 bfd_byte *esym;
6605 sym.st_name = h->dynstr_index;
6606 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6607 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6609 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6610 bucket = h->u.elf_hash_value % bucketcount;
6611 hash_entry_size
6612 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6613 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6614 + (bucket + 2) * hash_entry_size);
6615 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6616 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6617 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6618 ((bfd_byte *) finfo->hash_sec->contents
6619 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6621 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6623 Elf_Internal_Versym iversym;
6624 Elf_External_Versym *eversym;
6626 if (!h->def_regular)
6628 if (h->verinfo.verdef == NULL)
6629 iversym.vs_vers = 0;
6630 else
6631 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6633 else
6635 if (h->verinfo.vertree == NULL)
6636 iversym.vs_vers = 1;
6637 else
6638 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6639 if (finfo->info->create_default_symver)
6640 iversym.vs_vers++;
6643 if (h->hidden)
6644 iversym.vs_vers |= VERSYM_HIDDEN;
6646 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6647 eversym += h->dynindx;
6648 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6652 /* If we're stripping it, then it was just a dynamic symbol, and
6653 there's nothing else to do. */
6654 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6655 return TRUE;
6657 h->indx = bfd_get_symcount (finfo->output_bfd);
6659 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6661 eoinfo->failed = TRUE;
6662 return FALSE;
6665 return TRUE;
6668 /* Return TRUE if special handling is done for relocs in SEC against
6669 symbols defined in discarded sections. */
6671 static bfd_boolean
6672 elf_section_ignore_discarded_relocs (asection *sec)
6674 const struct elf_backend_data *bed;
6676 switch (sec->sec_info_type)
6678 case ELF_INFO_TYPE_STABS:
6679 case ELF_INFO_TYPE_EH_FRAME:
6680 return TRUE;
6681 default:
6682 break;
6685 bed = get_elf_backend_data (sec->owner);
6686 if (bed->elf_backend_ignore_discarded_relocs != NULL
6687 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6688 return TRUE;
6690 return FALSE;
6693 /* Return a mask saying how ld should treat relocations in SEC against
6694 symbols defined in discarded sections. If this function returns
6695 COMPLAIN set, ld will issue a warning message. If this function
6696 returns PRETEND set, and the discarded section was link-once and the
6697 same size as the kept link-once section, ld will pretend that the
6698 symbol was actually defined in the kept section. Otherwise ld will
6699 zero the reloc (at least that is the intent, but some cooperation by
6700 the target dependent code is needed, particularly for REL targets). */
6702 unsigned int
6703 _bfd_elf_default_action_discarded (asection *sec)
6705 if (sec->flags & SEC_DEBUGGING)
6706 return PRETEND;
6708 if (strcmp (".eh_frame", sec->name) == 0)
6709 return 0;
6711 if (strcmp (".gcc_except_table", sec->name) == 0)
6712 return 0;
6714 return COMPLAIN | PRETEND;
6717 /* Find a match between a section and a member of a section group. */
6719 static asection *
6720 match_group_member (asection *sec, asection *group)
6722 asection *first = elf_next_in_group (group);
6723 asection *s = first;
6725 while (s != NULL)
6727 if (bfd_elf_match_symbols_in_sections (s, sec))
6728 return s;
6730 if (s == first)
6731 break;
6734 return NULL;
6737 /* Check if the kept section of a discarded section SEC can be used
6738 to replace it. Return the replacement if it is OK. Otherwise return
6739 NULL. */
6741 asection *
6742 _bfd_elf_check_kept_section (asection *sec)
6744 asection *kept;
6746 kept = sec->kept_section;
6747 if (kept != NULL)
6749 if (elf_sec_group (sec) != NULL)
6750 kept = match_group_member (sec, kept);
6751 if (kept != NULL && sec->size != kept->size)
6752 kept = NULL;
6754 return kept;
6757 /* Link an input file into the linker output file. This function
6758 handles all the sections and relocations of the input file at once.
6759 This is so that we only have to read the local symbols once, and
6760 don't have to keep them in memory. */
6762 static bfd_boolean
6763 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6765 bfd_boolean (*relocate_section)
6766 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6767 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6768 bfd *output_bfd;
6769 Elf_Internal_Shdr *symtab_hdr;
6770 size_t locsymcount;
6771 size_t extsymoff;
6772 Elf_Internal_Sym *isymbuf;
6773 Elf_Internal_Sym *isym;
6774 Elf_Internal_Sym *isymend;
6775 long *pindex;
6776 asection **ppsection;
6777 asection *o;
6778 const struct elf_backend_data *bed;
6779 bfd_boolean emit_relocs;
6780 struct elf_link_hash_entry **sym_hashes;
6782 output_bfd = finfo->output_bfd;
6783 bed = get_elf_backend_data (output_bfd);
6784 relocate_section = bed->elf_backend_relocate_section;
6786 /* If this is a dynamic object, we don't want to do anything here:
6787 we don't want the local symbols, and we don't want the section
6788 contents. */
6789 if ((input_bfd->flags & DYNAMIC) != 0)
6790 return TRUE;
6792 emit_relocs = (finfo->info->relocatable
6793 || finfo->info->emitrelocations);
6795 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6796 if (elf_bad_symtab (input_bfd))
6798 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6799 extsymoff = 0;
6801 else
6803 locsymcount = symtab_hdr->sh_info;
6804 extsymoff = symtab_hdr->sh_info;
6807 /* Read the local symbols. */
6808 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6809 if (isymbuf == NULL && locsymcount != 0)
6811 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6812 finfo->internal_syms,
6813 finfo->external_syms,
6814 finfo->locsym_shndx);
6815 if (isymbuf == NULL)
6816 return FALSE;
6819 /* Find local symbol sections and adjust values of symbols in
6820 SEC_MERGE sections. Write out those local symbols we know are
6821 going into the output file. */
6822 isymend = isymbuf + locsymcount;
6823 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6824 isym < isymend;
6825 isym++, pindex++, ppsection++)
6827 asection *isec;
6828 const char *name;
6829 Elf_Internal_Sym osym;
6831 *pindex = -1;
6833 if (elf_bad_symtab (input_bfd))
6835 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6837 *ppsection = NULL;
6838 continue;
6842 if (isym->st_shndx == SHN_UNDEF)
6843 isec = bfd_und_section_ptr;
6844 else if (isym->st_shndx < SHN_LORESERVE
6845 || isym->st_shndx > SHN_HIRESERVE)
6847 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6848 if (isec
6849 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6850 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6851 isym->st_value =
6852 _bfd_merged_section_offset (output_bfd, &isec,
6853 elf_section_data (isec)->sec_info,
6854 isym->st_value);
6856 else if (isym->st_shndx == SHN_ABS)
6857 isec = bfd_abs_section_ptr;
6858 else if (isym->st_shndx == SHN_COMMON)
6859 isec = bfd_com_section_ptr;
6860 else
6862 /* Who knows? */
6863 isec = NULL;
6866 *ppsection = isec;
6868 /* Don't output the first, undefined, symbol. */
6869 if (ppsection == finfo->sections)
6870 continue;
6872 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6874 /* We never output section symbols. Instead, we use the
6875 section symbol of the corresponding section in the output
6876 file. */
6877 continue;
6880 /* If we are stripping all symbols, we don't want to output this
6881 one. */
6882 if (finfo->info->strip == strip_all)
6883 continue;
6885 /* If we are discarding all local symbols, we don't want to
6886 output this one. If we are generating a relocatable output
6887 file, then some of the local symbols may be required by
6888 relocs; we output them below as we discover that they are
6889 needed. */
6890 if (finfo->info->discard == discard_all)
6891 continue;
6893 /* If this symbol is defined in a section which we are
6894 discarding, we don't need to keep it, but note that
6895 linker_mark is only reliable for sections that have contents.
6896 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
6897 as well as linker_mark. */
6898 if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6899 && (isec == NULL
6900 || (! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
6901 || (! finfo->info->relocatable
6902 && (isec->flags & SEC_EXCLUDE) != 0)))
6903 continue;
6905 /* If the section is not in the output BFD's section list, it is not
6906 being output. */
6907 if (bfd_section_removed_from_list (output_bfd, isec->output_section))
6908 continue;
6910 /* Get the name of the symbol. */
6911 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6912 isym->st_name);
6913 if (name == NULL)
6914 return FALSE;
6916 /* See if we are discarding symbols with this name. */
6917 if ((finfo->info->strip == strip_some
6918 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6919 == NULL))
6920 || (((finfo->info->discard == discard_sec_merge
6921 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6922 || finfo->info->discard == discard_l)
6923 && bfd_is_local_label_name (input_bfd, name)))
6924 continue;
6926 /* If we get here, we are going to output this symbol. */
6928 osym = *isym;
6930 /* Adjust the section index for the output file. */
6931 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6932 isec->output_section);
6933 if (osym.st_shndx == SHN_BAD)
6934 return FALSE;
6936 *pindex = bfd_get_symcount (output_bfd);
6938 /* ELF symbols in relocatable files are section relative, but
6939 in executable files they are virtual addresses. Note that
6940 this code assumes that all ELF sections have an associated
6941 BFD section with a reasonable value for output_offset; below
6942 we assume that they also have a reasonable value for
6943 output_section. Any special sections must be set up to meet
6944 these requirements. */
6945 osym.st_value += isec->output_offset;
6946 if (! finfo->info->relocatable)
6948 osym.st_value += isec->output_section->vma;
6949 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
6951 /* STT_TLS symbols are relative to PT_TLS segment base. */
6952 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6953 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6957 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
6958 return FALSE;
6961 /* Relocate the contents of each section. */
6962 sym_hashes = elf_sym_hashes (input_bfd);
6963 for (o = input_bfd->sections; o != NULL; o = o->next)
6965 bfd_byte *contents;
6967 if (! o->linker_mark)
6969 /* This section was omitted from the link. */
6970 continue;
6973 if ((o->flags & SEC_HAS_CONTENTS) == 0
6974 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
6975 continue;
6977 if ((o->flags & SEC_LINKER_CREATED) != 0)
6979 /* Section was created by _bfd_elf_link_create_dynamic_sections
6980 or somesuch. */
6981 continue;
6984 /* Get the contents of the section. They have been cached by a
6985 relaxation routine. Note that o is a section in an input
6986 file, so the contents field will not have been set by any of
6987 the routines which work on output files. */
6988 if (elf_section_data (o)->this_hdr.contents != NULL)
6989 contents = elf_section_data (o)->this_hdr.contents;
6990 else
6992 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
6994 contents = finfo->contents;
6995 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
6996 return FALSE;
6999 if ((o->flags & SEC_RELOC) != 0)
7001 Elf_Internal_Rela *internal_relocs;
7002 bfd_vma r_type_mask;
7003 int r_sym_shift;
7005 /* Get the swapped relocs. */
7006 internal_relocs
7007 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
7008 finfo->internal_relocs, FALSE);
7009 if (internal_relocs == NULL
7010 && o->reloc_count > 0)
7011 return FALSE;
7013 if (bed->s->arch_size == 32)
7015 r_type_mask = 0xff;
7016 r_sym_shift = 8;
7018 else
7020 r_type_mask = 0xffffffff;
7021 r_sym_shift = 32;
7024 /* Run through the relocs looking for any against symbols
7025 from discarded sections and section symbols from
7026 removed link-once sections. Complain about relocs
7027 against discarded sections. Zero relocs against removed
7028 link-once sections. Preserve debug information as much
7029 as we can. */
7030 if (!elf_section_ignore_discarded_relocs (o))
7032 Elf_Internal_Rela *rel, *relend;
7033 unsigned int action = (*bed->action_discarded) (o);
7035 rel = internal_relocs;
7036 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
7037 for ( ; rel < relend; rel++)
7039 unsigned long r_symndx = rel->r_info >> r_sym_shift;
7040 asection **ps, *sec;
7041 struct elf_link_hash_entry *h = NULL;
7042 const char *sym_name;
7044 if (r_symndx == STN_UNDEF)
7045 continue;
7047 if (r_symndx >= locsymcount
7048 || (elf_bad_symtab (input_bfd)
7049 && finfo->sections[r_symndx] == NULL))
7051 h = sym_hashes[r_symndx - extsymoff];
7053 /* Badly formatted input files can contain relocs that
7054 reference non-existant symbols. Check here so that
7055 we do not seg fault. */
7056 if (h == NULL)
7058 char buffer [32];
7060 sprintf_vma (buffer, rel->r_info);
7061 (*_bfd_error_handler)
7062 (_("error: %B contains a reloc (0x%s) for section %A "
7063 "that references a non-existent global symbol"),
7064 input_bfd, o, buffer);
7065 bfd_set_error (bfd_error_bad_value);
7066 return FALSE;
7069 while (h->root.type == bfd_link_hash_indirect
7070 || h->root.type == bfd_link_hash_warning)
7071 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7073 if (h->root.type != bfd_link_hash_defined
7074 && h->root.type != bfd_link_hash_defweak)
7075 continue;
7077 ps = &h->root.u.def.section;
7078 sym_name = h->root.root.string;
7080 else
7082 Elf_Internal_Sym *sym = isymbuf + r_symndx;
7083 ps = &finfo->sections[r_symndx];
7084 sym_name = bfd_elf_sym_name (input_bfd,
7085 symtab_hdr,
7086 sym, *ps);
7089 /* Complain if the definition comes from a
7090 discarded section. */
7091 if ((sec = *ps) != NULL && elf_discarded_section (sec))
7093 BFD_ASSERT (r_symndx != 0);
7094 if (action & COMPLAIN)
7095 (*finfo->info->callbacks->einfo)
7096 (_("%X`%s' referenced in section `%A' of %B: "
7097 "defined in discarded section `%A' of %B\n"),
7098 sym_name, o, input_bfd, sec, sec->owner);
7100 /* Try to do the best we can to support buggy old
7101 versions of gcc. If we've warned, or this is
7102 debugging info, pretend that the symbol is
7103 really defined in the kept linkonce section.
7104 FIXME: This is quite broken. Modifying the
7105 symbol here means we will be changing all later
7106 uses of the symbol, not just in this section.
7107 The only thing that makes this half reasonable
7108 is that we warn in non-debug sections, and
7109 debug sections tend to come after other
7110 sections. */
7111 if (action & PRETEND)
7113 asection *kept;
7115 kept = _bfd_elf_check_kept_section (sec);
7116 if (kept != NULL)
7118 *ps = kept;
7119 continue;
7123 /* Remove the symbol reference from the reloc, but
7124 don't kill the reloc completely. This is so that
7125 a zero value will be written into the section,
7126 which may have non-zero contents put there by the
7127 assembler. Zero in things like an eh_frame fde
7128 pc_begin allows stack unwinders to recognize the
7129 fde as bogus. */
7130 rel->r_info &= r_type_mask;
7131 rel->r_addend = 0;
7136 /* Relocate the section by invoking a back end routine.
7138 The back end routine is responsible for adjusting the
7139 section contents as necessary, and (if using Rela relocs
7140 and generating a relocatable output file) adjusting the
7141 reloc addend as necessary.
7143 The back end routine does not have to worry about setting
7144 the reloc address or the reloc symbol index.
7146 The back end routine is given a pointer to the swapped in
7147 internal symbols, and can access the hash table entries
7148 for the external symbols via elf_sym_hashes (input_bfd).
7150 When generating relocatable output, the back end routine
7151 must handle STB_LOCAL/STT_SECTION symbols specially. The
7152 output symbol is going to be a section symbol
7153 corresponding to the output section, which will require
7154 the addend to be adjusted. */
7156 if (! (*relocate_section) (output_bfd, finfo->info,
7157 input_bfd, o, contents,
7158 internal_relocs,
7159 isymbuf,
7160 finfo->sections))
7161 return FALSE;
7163 if (emit_relocs)
7165 Elf_Internal_Rela *irela;
7166 Elf_Internal_Rela *irelaend;
7167 bfd_vma last_offset;
7168 struct elf_link_hash_entry **rel_hash;
7169 struct elf_link_hash_entry **rel_hash_list;
7170 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7171 unsigned int next_erel;
7172 bfd_boolean rela_normal;
7174 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7175 rela_normal = (bed->rela_normal
7176 && (input_rel_hdr->sh_entsize
7177 == bed->s->sizeof_rela));
7179 /* Adjust the reloc addresses and symbol indices. */
7181 irela = internal_relocs;
7182 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7183 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7184 + elf_section_data (o->output_section)->rel_count
7185 + elf_section_data (o->output_section)->rel_count2);
7186 rel_hash_list = rel_hash;
7187 last_offset = o->output_offset;
7188 if (!finfo->info->relocatable)
7189 last_offset += o->output_section->vma;
7190 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7192 unsigned long r_symndx;
7193 asection *sec;
7194 Elf_Internal_Sym sym;
7196 if (next_erel == bed->s->int_rels_per_ext_rel)
7198 rel_hash++;
7199 next_erel = 0;
7202 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7203 finfo->info, o,
7204 irela->r_offset);
7205 if (irela->r_offset >= (bfd_vma) -2)
7207 /* This is a reloc for a deleted entry or somesuch.
7208 Turn it into an R_*_NONE reloc, at the same
7209 offset as the last reloc. elf_eh_frame.c and
7210 elf_bfd_discard_info rely on reloc offsets
7211 being ordered. */
7212 irela->r_offset = last_offset;
7213 irela->r_info = 0;
7214 irela->r_addend = 0;
7215 continue;
7218 irela->r_offset += o->output_offset;
7220 /* Relocs in an executable have to be virtual addresses. */
7221 if (!finfo->info->relocatable)
7222 irela->r_offset += o->output_section->vma;
7224 last_offset = irela->r_offset;
7226 r_symndx = irela->r_info >> r_sym_shift;
7227 if (r_symndx == STN_UNDEF)
7228 continue;
7230 if (r_symndx >= locsymcount
7231 || (elf_bad_symtab (input_bfd)
7232 && finfo->sections[r_symndx] == NULL))
7234 struct elf_link_hash_entry *rh;
7235 unsigned long indx;
7237 /* This is a reloc against a global symbol. We
7238 have not yet output all the local symbols, so
7239 we do not know the symbol index of any global
7240 symbol. We set the rel_hash entry for this
7241 reloc to point to the global hash table entry
7242 for this symbol. The symbol index is then
7243 set at the end of bfd_elf_final_link. */
7244 indx = r_symndx - extsymoff;
7245 rh = elf_sym_hashes (input_bfd)[indx];
7246 while (rh->root.type == bfd_link_hash_indirect
7247 || rh->root.type == bfd_link_hash_warning)
7248 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7250 /* Setting the index to -2 tells
7251 elf_link_output_extsym that this symbol is
7252 used by a reloc. */
7253 BFD_ASSERT (rh->indx < 0);
7254 rh->indx = -2;
7256 *rel_hash = rh;
7258 continue;
7261 /* This is a reloc against a local symbol. */
7263 *rel_hash = NULL;
7264 sym = isymbuf[r_symndx];
7265 sec = finfo->sections[r_symndx];
7266 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7268 /* I suppose the backend ought to fill in the
7269 section of any STT_SECTION symbol against a
7270 processor specific section. */
7271 r_symndx = 0;
7272 if (bfd_is_abs_section (sec))
7274 else if (sec == NULL || sec->owner == NULL)
7276 bfd_set_error (bfd_error_bad_value);
7277 return FALSE;
7279 else
7281 asection *osec = sec->output_section;
7283 /* If we have discarded a section, the output
7284 section will be the absolute section. In
7285 case of discarded link-once and discarded
7286 SEC_MERGE sections, use the kept section. */
7287 if (bfd_is_abs_section (osec)
7288 && sec->kept_section != NULL
7289 && sec->kept_section->output_section != NULL)
7291 osec = sec->kept_section->output_section;
7292 irela->r_addend -= osec->vma;
7295 if (!bfd_is_abs_section (osec))
7297 r_symndx = osec->target_index;
7298 BFD_ASSERT (r_symndx != 0);
7302 /* Adjust the addend according to where the
7303 section winds up in the output section. */
7304 if (rela_normal)
7305 irela->r_addend += sec->output_offset;
7307 else
7309 if (finfo->indices[r_symndx] == -1)
7311 unsigned long shlink;
7312 const char *name;
7313 asection *osec;
7315 if (finfo->info->strip == strip_all)
7317 /* You can't do ld -r -s. */
7318 bfd_set_error (bfd_error_invalid_operation);
7319 return FALSE;
7322 /* This symbol was skipped earlier, but
7323 since it is needed by a reloc, we
7324 must output it now. */
7325 shlink = symtab_hdr->sh_link;
7326 name = (bfd_elf_string_from_elf_section
7327 (input_bfd, shlink, sym.st_name));
7328 if (name == NULL)
7329 return FALSE;
7331 osec = sec->output_section;
7332 sym.st_shndx =
7333 _bfd_elf_section_from_bfd_section (output_bfd,
7334 osec);
7335 if (sym.st_shndx == SHN_BAD)
7336 return FALSE;
7338 sym.st_value += sec->output_offset;
7339 if (! finfo->info->relocatable)
7341 sym.st_value += osec->vma;
7342 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7344 /* STT_TLS symbols are relative to PT_TLS
7345 segment base. */
7346 BFD_ASSERT (elf_hash_table (finfo->info)
7347 ->tls_sec != NULL);
7348 sym.st_value -= (elf_hash_table (finfo->info)
7349 ->tls_sec->vma);
7353 finfo->indices[r_symndx]
7354 = bfd_get_symcount (output_bfd);
7356 if (! elf_link_output_sym (finfo, name, &sym, sec,
7357 NULL))
7358 return FALSE;
7361 r_symndx = finfo->indices[r_symndx];
7364 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7365 | (irela->r_info & r_type_mask));
7368 /* Swap out the relocs. */
7369 if (input_rel_hdr->sh_size != 0
7370 && !bed->elf_backend_emit_relocs (output_bfd, o,
7371 input_rel_hdr,
7372 internal_relocs,
7373 rel_hash_list))
7374 return FALSE;
7376 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7377 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7379 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7380 * bed->s->int_rels_per_ext_rel);
7381 rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
7382 if (!bed->elf_backend_emit_relocs (output_bfd, o,
7383 input_rel_hdr2,
7384 internal_relocs,
7385 rel_hash_list))
7386 return FALSE;
7391 /* Write out the modified section contents. */
7392 if (bed->elf_backend_write_section
7393 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7395 /* Section written out. */
7397 else switch (o->sec_info_type)
7399 case ELF_INFO_TYPE_STABS:
7400 if (! (_bfd_write_section_stabs
7401 (output_bfd,
7402 &elf_hash_table (finfo->info)->stab_info,
7403 o, &elf_section_data (o)->sec_info, contents)))
7404 return FALSE;
7405 break;
7406 case ELF_INFO_TYPE_MERGE:
7407 if (! _bfd_write_merged_section (output_bfd, o,
7408 elf_section_data (o)->sec_info))
7409 return FALSE;
7410 break;
7411 case ELF_INFO_TYPE_EH_FRAME:
7413 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7414 o, contents))
7415 return FALSE;
7417 break;
7418 default:
7420 if (! (o->flags & SEC_EXCLUDE)
7421 && ! bfd_set_section_contents (output_bfd, o->output_section,
7422 contents,
7423 (file_ptr) o->output_offset,
7424 o->size))
7425 return FALSE;
7427 break;
7431 return TRUE;
7434 /* Generate a reloc when linking an ELF file. This is a reloc
7435 requested by the linker, and does come from any input file. This
7436 is used to build constructor and destructor tables when linking
7437 with -Ur. */
7439 static bfd_boolean
7440 elf_reloc_link_order (bfd *output_bfd,
7441 struct bfd_link_info *info,
7442 asection *output_section,
7443 struct bfd_link_order *link_order)
7445 reloc_howto_type *howto;
7446 long indx;
7447 bfd_vma offset;
7448 bfd_vma addend;
7449 struct elf_link_hash_entry **rel_hash_ptr;
7450 Elf_Internal_Shdr *rel_hdr;
7451 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7452 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7453 bfd_byte *erel;
7454 unsigned int i;
7456 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7457 if (howto == NULL)
7459 bfd_set_error (bfd_error_bad_value);
7460 return FALSE;
7463 addend = link_order->u.reloc.p->addend;
7465 /* Figure out the symbol index. */
7466 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7467 + elf_section_data (output_section)->rel_count
7468 + elf_section_data (output_section)->rel_count2);
7469 if (link_order->type == bfd_section_reloc_link_order)
7471 indx = link_order->u.reloc.p->u.section->target_index;
7472 BFD_ASSERT (indx != 0);
7473 *rel_hash_ptr = NULL;
7475 else
7477 struct elf_link_hash_entry *h;
7479 /* Treat a reloc against a defined symbol as though it were
7480 actually against the section. */
7481 h = ((struct elf_link_hash_entry *)
7482 bfd_wrapped_link_hash_lookup (output_bfd, info,
7483 link_order->u.reloc.p->u.name,
7484 FALSE, FALSE, TRUE));
7485 if (h != NULL
7486 && (h->root.type == bfd_link_hash_defined
7487 || h->root.type == bfd_link_hash_defweak))
7489 asection *section;
7491 section = h->root.u.def.section;
7492 indx = section->output_section->target_index;
7493 *rel_hash_ptr = NULL;
7494 /* It seems that we ought to add the symbol value to the
7495 addend here, but in practice it has already been added
7496 because it was passed to constructor_callback. */
7497 addend += section->output_section->vma + section->output_offset;
7499 else if (h != NULL)
7501 /* Setting the index to -2 tells elf_link_output_extsym that
7502 this symbol is used by a reloc. */
7503 h->indx = -2;
7504 *rel_hash_ptr = h;
7505 indx = 0;
7507 else
7509 if (! ((*info->callbacks->unattached_reloc)
7510 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7511 return FALSE;
7512 indx = 0;
7516 /* If this is an inplace reloc, we must write the addend into the
7517 object file. */
7518 if (howto->partial_inplace && addend != 0)
7520 bfd_size_type size;
7521 bfd_reloc_status_type rstat;
7522 bfd_byte *buf;
7523 bfd_boolean ok;
7524 const char *sym_name;
7526 size = bfd_get_reloc_size (howto);
7527 buf = bfd_zmalloc (size);
7528 if (buf == NULL)
7529 return FALSE;
7530 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7531 switch (rstat)
7533 case bfd_reloc_ok:
7534 break;
7536 default:
7537 case bfd_reloc_outofrange:
7538 abort ();
7540 case bfd_reloc_overflow:
7541 if (link_order->type == bfd_section_reloc_link_order)
7542 sym_name = bfd_section_name (output_bfd,
7543 link_order->u.reloc.p->u.section);
7544 else
7545 sym_name = link_order->u.reloc.p->u.name;
7546 if (! ((*info->callbacks->reloc_overflow)
7547 (info, NULL, sym_name, howto->name, addend, NULL,
7548 NULL, (bfd_vma) 0)))
7550 free (buf);
7551 return FALSE;
7553 break;
7555 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7556 link_order->offset, size);
7557 free (buf);
7558 if (! ok)
7559 return FALSE;
7562 /* The address of a reloc is relative to the section in a
7563 relocatable file, and is a virtual address in an executable
7564 file. */
7565 offset = link_order->offset;
7566 if (! info->relocatable)
7567 offset += output_section->vma;
7569 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7571 irel[i].r_offset = offset;
7572 irel[i].r_info = 0;
7573 irel[i].r_addend = 0;
7575 if (bed->s->arch_size == 32)
7576 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7577 else
7578 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7580 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7581 erel = rel_hdr->contents;
7582 if (rel_hdr->sh_type == SHT_REL)
7584 erel += (elf_section_data (output_section)->rel_count
7585 * bed->s->sizeof_rel);
7586 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7588 else
7590 irel[0].r_addend = addend;
7591 erel += (elf_section_data (output_section)->rel_count
7592 * bed->s->sizeof_rela);
7593 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7596 ++elf_section_data (output_section)->rel_count;
7598 return TRUE;
7602 /* Get the output vma of the section pointed to by the sh_link field. */
7604 static bfd_vma
7605 elf_get_linked_section_vma (struct bfd_link_order *p)
7607 Elf_Internal_Shdr **elf_shdrp;
7608 asection *s;
7609 int elfsec;
7611 s = p->u.indirect.section;
7612 elf_shdrp = elf_elfsections (s->owner);
7613 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7614 elfsec = elf_shdrp[elfsec]->sh_link;
7615 /* PR 290:
7616 The Intel C compiler generates SHT_IA_64_UNWIND with
7617 SHF_LINK_ORDER. But it doesn't set theh sh_link or
7618 sh_info fields. Hence we could get the situation
7619 where elfsec is 0. */
7620 if (elfsec == 0)
7622 const struct elf_backend_data *bed
7623 = get_elf_backend_data (s->owner);
7624 if (bed->link_order_error_handler)
7625 bed->link_order_error_handler
7626 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
7627 return 0;
7629 else
7631 s = elf_shdrp[elfsec]->bfd_section;
7632 return s->output_section->vma + s->output_offset;
7637 /* Compare two sections based on the locations of the sections they are
7638 linked to. Used by elf_fixup_link_order. */
7640 static int
7641 compare_link_order (const void * a, const void * b)
7643 bfd_vma apos;
7644 bfd_vma bpos;
7646 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7647 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7648 if (apos < bpos)
7649 return -1;
7650 return apos > bpos;
7654 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7655 order as their linked sections. Returns false if this could not be done
7656 because an output section includes both ordered and unordered
7657 sections. Ideally we'd do this in the linker proper. */
7659 static bfd_boolean
7660 elf_fixup_link_order (bfd *abfd, asection *o)
7662 int seen_linkorder;
7663 int seen_other;
7664 int n;
7665 struct bfd_link_order *p;
7666 bfd *sub;
7667 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7668 int elfsec;
7669 struct bfd_link_order **sections;
7670 asection *s;
7671 bfd_vma offset;
7673 seen_other = 0;
7674 seen_linkorder = 0;
7675 for (p = o->map_head.link_order; p != NULL; p = p->next)
7677 if (p->type == bfd_indirect_link_order
7678 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7679 == bfd_target_elf_flavour)
7680 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7682 s = p->u.indirect.section;
7683 elfsec = _bfd_elf_section_from_bfd_section (sub, s);
7684 if (elfsec != -1
7685 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7686 seen_linkorder++;
7687 else
7688 seen_other++;
7690 else
7691 seen_other++;
7694 if (!seen_linkorder)
7695 return TRUE;
7697 if (seen_other && seen_linkorder)
7699 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
7701 bfd_set_error (bfd_error_bad_value);
7702 return FALSE;
7705 sections = (struct bfd_link_order **)
7706 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7707 seen_linkorder = 0;
7709 for (p = o->map_head.link_order; p != NULL; p = p->next)
7711 sections[seen_linkorder++] = p;
7713 /* Sort the input sections in the order of their linked section. */
7714 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7715 compare_link_order);
7717 /* Change the offsets of the sections. */
7718 offset = 0;
7719 for (n = 0; n < seen_linkorder; n++)
7721 s = sections[n]->u.indirect.section;
7722 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7723 s->output_offset = offset;
7724 sections[n]->offset = offset;
7725 offset += sections[n]->size;
7728 return TRUE;
7732 /* Do the final step of an ELF link. */
7734 bfd_boolean
7735 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7737 bfd_boolean dynamic;
7738 bfd_boolean emit_relocs;
7739 bfd *dynobj;
7740 struct elf_final_link_info finfo;
7741 register asection *o;
7742 register struct bfd_link_order *p;
7743 register bfd *sub;
7744 bfd_size_type max_contents_size;
7745 bfd_size_type max_external_reloc_size;
7746 bfd_size_type max_internal_reloc_count;
7747 bfd_size_type max_sym_count;
7748 bfd_size_type max_sym_shndx_count;
7749 file_ptr off;
7750 Elf_Internal_Sym elfsym;
7751 unsigned int i;
7752 Elf_Internal_Shdr *symtab_hdr;
7753 Elf_Internal_Shdr *symtab_shndx_hdr;
7754 Elf_Internal_Shdr *symstrtab_hdr;
7755 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7756 struct elf_outext_info eoinfo;
7757 bfd_boolean merged;
7758 size_t relativecount = 0;
7759 asection *reldyn = 0;
7760 bfd_size_type amt;
7762 if (! is_elf_hash_table (info->hash))
7763 return FALSE;
7765 if (info->shared)
7766 abfd->flags |= DYNAMIC;
7768 dynamic = elf_hash_table (info)->dynamic_sections_created;
7769 dynobj = elf_hash_table (info)->dynobj;
7771 emit_relocs = (info->relocatable
7772 || info->emitrelocations
7773 || bed->elf_backend_emit_relocs);
7775 finfo.info = info;
7776 finfo.output_bfd = abfd;
7777 finfo.symstrtab = _bfd_elf_stringtab_init ();
7778 if (finfo.symstrtab == NULL)
7779 return FALSE;
7781 if (! dynamic)
7783 finfo.dynsym_sec = NULL;
7784 finfo.hash_sec = NULL;
7785 finfo.symver_sec = NULL;
7787 else
7789 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7790 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7791 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7792 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7793 /* Note that it is OK if symver_sec is NULL. */
7796 finfo.contents = NULL;
7797 finfo.external_relocs = NULL;
7798 finfo.internal_relocs = NULL;
7799 finfo.external_syms = NULL;
7800 finfo.locsym_shndx = NULL;
7801 finfo.internal_syms = NULL;
7802 finfo.indices = NULL;
7803 finfo.sections = NULL;
7804 finfo.symbuf = NULL;
7805 finfo.symshndxbuf = NULL;
7806 finfo.symbuf_count = 0;
7807 finfo.shndxbuf_size = 0;
7809 /* Count up the number of relocations we will output for each output
7810 section, so that we know the sizes of the reloc sections. We
7811 also figure out some maximum sizes. */
7812 max_contents_size = 0;
7813 max_external_reloc_size = 0;
7814 max_internal_reloc_count = 0;
7815 max_sym_count = 0;
7816 max_sym_shndx_count = 0;
7817 merged = FALSE;
7818 for (o = abfd->sections; o != NULL; o = o->next)
7820 struct bfd_elf_section_data *esdo = elf_section_data (o);
7821 o->reloc_count = 0;
7823 for (p = o->map_head.link_order; p != NULL; p = p->next)
7825 unsigned int reloc_count = 0;
7826 struct bfd_elf_section_data *esdi = NULL;
7827 unsigned int *rel_count1;
7829 if (p->type == bfd_section_reloc_link_order
7830 || p->type == bfd_symbol_reloc_link_order)
7831 reloc_count = 1;
7832 else if (p->type == bfd_indirect_link_order)
7834 asection *sec;
7836 sec = p->u.indirect.section;
7837 esdi = elf_section_data (sec);
7839 /* Mark all sections which are to be included in the
7840 link. This will normally be every section. We need
7841 to do this so that we can identify any sections which
7842 the linker has decided to not include. */
7843 sec->linker_mark = TRUE;
7845 if (sec->flags & SEC_MERGE)
7846 merged = TRUE;
7848 if (info->relocatable || info->emitrelocations)
7849 reloc_count = sec->reloc_count;
7850 else if (bed->elf_backend_count_relocs)
7852 Elf_Internal_Rela * relocs;
7854 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7855 info->keep_memory);
7857 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7859 if (elf_section_data (o)->relocs != relocs)
7860 free (relocs);
7863 if (sec->rawsize > max_contents_size)
7864 max_contents_size = sec->rawsize;
7865 if (sec->size > max_contents_size)
7866 max_contents_size = sec->size;
7868 /* We are interested in just local symbols, not all
7869 symbols. */
7870 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7871 && (sec->owner->flags & DYNAMIC) == 0)
7873 size_t sym_count;
7875 if (elf_bad_symtab (sec->owner))
7876 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7877 / bed->s->sizeof_sym);
7878 else
7879 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7881 if (sym_count > max_sym_count)
7882 max_sym_count = sym_count;
7884 if (sym_count > max_sym_shndx_count
7885 && elf_symtab_shndx (sec->owner) != 0)
7886 max_sym_shndx_count = sym_count;
7888 if ((sec->flags & SEC_RELOC) != 0)
7890 size_t ext_size;
7892 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7893 if (ext_size > max_external_reloc_size)
7894 max_external_reloc_size = ext_size;
7895 if (sec->reloc_count > max_internal_reloc_count)
7896 max_internal_reloc_count = sec->reloc_count;
7901 if (reloc_count == 0)
7902 continue;
7904 o->reloc_count += reloc_count;
7906 /* MIPS may have a mix of REL and RELA relocs on sections.
7907 To support this curious ABI we keep reloc counts in
7908 elf_section_data too. We must be careful to add the
7909 relocations from the input section to the right output
7910 count. FIXME: Get rid of one count. We have
7911 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7912 rel_count1 = &esdo->rel_count;
7913 if (esdi != NULL)
7915 bfd_boolean same_size;
7916 bfd_size_type entsize1;
7918 entsize1 = esdi->rel_hdr.sh_entsize;
7919 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7920 || entsize1 == bed->s->sizeof_rela);
7921 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7923 if (!same_size)
7924 rel_count1 = &esdo->rel_count2;
7926 if (esdi->rel_hdr2 != NULL)
7928 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7929 unsigned int alt_count;
7930 unsigned int *rel_count2;
7932 BFD_ASSERT (entsize2 != entsize1
7933 && (entsize2 == bed->s->sizeof_rel
7934 || entsize2 == bed->s->sizeof_rela));
7936 rel_count2 = &esdo->rel_count2;
7937 if (!same_size)
7938 rel_count2 = &esdo->rel_count;
7940 /* The following is probably too simplistic if the
7941 backend counts output relocs unusually. */
7942 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7943 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
7944 *rel_count2 += alt_count;
7945 reloc_count -= alt_count;
7948 *rel_count1 += reloc_count;
7951 if (o->reloc_count > 0)
7952 o->flags |= SEC_RELOC;
7953 else
7955 /* Explicitly clear the SEC_RELOC flag. The linker tends to
7956 set it (this is probably a bug) and if it is set
7957 assign_section_numbers will create a reloc section. */
7958 o->flags &=~ SEC_RELOC;
7961 /* If the SEC_ALLOC flag is not set, force the section VMA to
7962 zero. This is done in elf_fake_sections as well, but forcing
7963 the VMA to 0 here will ensure that relocs against these
7964 sections are handled correctly. */
7965 if ((o->flags & SEC_ALLOC) == 0
7966 && ! o->user_set_vma)
7967 o->vma = 0;
7970 if (! info->relocatable && merged)
7971 elf_link_hash_traverse (elf_hash_table (info),
7972 _bfd_elf_link_sec_merge_syms, abfd);
7974 /* Figure out the file positions for everything but the symbol table
7975 and the relocs. We set symcount to force assign_section_numbers
7976 to create a symbol table. */
7977 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
7978 BFD_ASSERT (! abfd->output_has_begun);
7979 if (! _bfd_elf_compute_section_file_positions (abfd, info))
7980 goto error_return;
7982 /* Set sizes, and assign file positions for reloc sections. */
7983 for (o = abfd->sections; o != NULL; o = o->next)
7985 if ((o->flags & SEC_RELOC) != 0)
7987 if (!(_bfd_elf_link_size_reloc_section
7988 (abfd, &elf_section_data (o)->rel_hdr, o)))
7989 goto error_return;
7991 if (elf_section_data (o)->rel_hdr2
7992 && !(_bfd_elf_link_size_reloc_section
7993 (abfd, elf_section_data (o)->rel_hdr2, o)))
7994 goto error_return;
7997 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
7998 to count upwards while actually outputting the relocations. */
7999 elf_section_data (o)->rel_count = 0;
8000 elf_section_data (o)->rel_count2 = 0;
8003 _bfd_elf_assign_file_positions_for_relocs (abfd);
8005 /* We have now assigned file positions for all the sections except
8006 .symtab and .strtab. We start the .symtab section at the current
8007 file position, and write directly to it. We build the .strtab
8008 section in memory. */
8009 bfd_get_symcount (abfd) = 0;
8010 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
8011 /* sh_name is set in prep_headers. */
8012 symtab_hdr->sh_type = SHT_SYMTAB;
8013 /* sh_flags, sh_addr and sh_size all start off zero. */
8014 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
8015 /* sh_link is set in assign_section_numbers. */
8016 /* sh_info is set below. */
8017 /* sh_offset is set just below. */
8018 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
8020 off = elf_tdata (abfd)->next_file_pos;
8021 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
8023 /* Note that at this point elf_tdata (abfd)->next_file_pos is
8024 incorrect. We do not yet know the size of the .symtab section.
8025 We correct next_file_pos below, after we do know the size. */
8027 /* Allocate a buffer to hold swapped out symbols. This is to avoid
8028 continuously seeking to the right position in the file. */
8029 if (! info->keep_memory || max_sym_count < 20)
8030 finfo.symbuf_size = 20;
8031 else
8032 finfo.symbuf_size = max_sym_count;
8033 amt = finfo.symbuf_size;
8034 amt *= bed->s->sizeof_sym;
8035 finfo.symbuf = bfd_malloc (amt);
8036 if (finfo.symbuf == NULL)
8037 goto error_return;
8038 if (elf_numsections (abfd) > SHN_LORESERVE)
8040 /* Wild guess at number of output symbols. realloc'd as needed. */
8041 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
8042 finfo.shndxbuf_size = amt;
8043 amt *= sizeof (Elf_External_Sym_Shndx);
8044 finfo.symshndxbuf = bfd_zmalloc (amt);
8045 if (finfo.symshndxbuf == NULL)
8046 goto error_return;
8049 /* Start writing out the symbol table. The first symbol is always a
8050 dummy symbol. */
8051 if (info->strip != strip_all
8052 || emit_relocs)
8054 elfsym.st_value = 0;
8055 elfsym.st_size = 0;
8056 elfsym.st_info = 0;
8057 elfsym.st_other = 0;
8058 elfsym.st_shndx = SHN_UNDEF;
8059 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
8060 NULL))
8061 goto error_return;
8064 /* Output a symbol for each section. We output these even if we are
8065 discarding local symbols, since they are used for relocs. These
8066 symbols have no names. We store the index of each one in the
8067 index field of the section, so that we can find it again when
8068 outputting relocs. */
8069 if (info->strip != strip_all
8070 || emit_relocs)
8072 elfsym.st_size = 0;
8073 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8074 elfsym.st_other = 0;
8075 for (i = 1; i < elf_numsections (abfd); i++)
8077 o = bfd_section_from_elf_index (abfd, i);
8078 if (o != NULL)
8079 o->target_index = bfd_get_symcount (abfd);
8080 elfsym.st_shndx = i;
8081 if (info->relocatable || o == NULL)
8082 elfsym.st_value = 0;
8083 else
8084 elfsym.st_value = o->vma;
8085 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
8086 goto error_return;
8087 if (i == SHN_LORESERVE - 1)
8088 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
8092 /* Allocate some memory to hold information read in from the input
8093 files. */
8094 if (max_contents_size != 0)
8096 finfo.contents = bfd_malloc (max_contents_size);
8097 if (finfo.contents == NULL)
8098 goto error_return;
8101 if (max_external_reloc_size != 0)
8103 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
8104 if (finfo.external_relocs == NULL)
8105 goto error_return;
8108 if (max_internal_reloc_count != 0)
8110 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
8111 amt *= sizeof (Elf_Internal_Rela);
8112 finfo.internal_relocs = bfd_malloc (amt);
8113 if (finfo.internal_relocs == NULL)
8114 goto error_return;
8117 if (max_sym_count != 0)
8119 amt = max_sym_count * bed->s->sizeof_sym;
8120 finfo.external_syms = bfd_malloc (amt);
8121 if (finfo.external_syms == NULL)
8122 goto error_return;
8124 amt = max_sym_count * sizeof (Elf_Internal_Sym);
8125 finfo.internal_syms = bfd_malloc (amt);
8126 if (finfo.internal_syms == NULL)
8127 goto error_return;
8129 amt = max_sym_count * sizeof (long);
8130 finfo.indices = bfd_malloc (amt);
8131 if (finfo.indices == NULL)
8132 goto error_return;
8134 amt = max_sym_count * sizeof (asection *);
8135 finfo.sections = bfd_malloc (amt);
8136 if (finfo.sections == NULL)
8137 goto error_return;
8140 if (max_sym_shndx_count != 0)
8142 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8143 finfo.locsym_shndx = bfd_malloc (amt);
8144 if (finfo.locsym_shndx == NULL)
8145 goto error_return;
8148 if (elf_hash_table (info)->tls_sec)
8150 bfd_vma base, end = 0;
8151 asection *sec;
8153 for (sec = elf_hash_table (info)->tls_sec;
8154 sec && (sec->flags & SEC_THREAD_LOCAL);
8155 sec = sec->next)
8157 bfd_vma size = sec->size;
8159 if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8161 struct bfd_link_order *o;
8163 for (o = sec->map_head.link_order; o != NULL; o = o->next)
8164 if (size < o->offset + o->size)
8165 size = o->offset + o->size;
8167 end = sec->vma + size;
8169 base = elf_hash_table (info)->tls_sec->vma;
8170 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8171 elf_hash_table (info)->tls_size = end - base;
8174 /* Reorder SHF_LINK_ORDER sections. */
8175 for (o = abfd->sections; o != NULL; o = o->next)
8177 if (!elf_fixup_link_order (abfd, o))
8178 return FALSE;
8181 /* Since ELF permits relocations to be against local symbols, we
8182 must have the local symbols available when we do the relocations.
8183 Since we would rather only read the local symbols once, and we
8184 would rather not keep them in memory, we handle all the
8185 relocations for a single input file at the same time.
8187 Unfortunately, there is no way to know the total number of local
8188 symbols until we have seen all of them, and the local symbol
8189 indices precede the global symbol indices. This means that when
8190 we are generating relocatable output, and we see a reloc against
8191 a global symbol, we can not know the symbol index until we have
8192 finished examining all the local symbols to see which ones we are
8193 going to output. To deal with this, we keep the relocations in
8194 memory, and don't output them until the end of the link. This is
8195 an unfortunate waste of memory, but I don't see a good way around
8196 it. Fortunately, it only happens when performing a relocatable
8197 link, which is not the common case. FIXME: If keep_memory is set
8198 we could write the relocs out and then read them again; I don't
8199 know how bad the memory loss will be. */
8201 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8202 sub->output_has_begun = FALSE;
8203 for (o = abfd->sections; o != NULL; o = o->next)
8205 for (p = o->map_head.link_order; p != NULL; p = p->next)
8207 if (p->type == bfd_indirect_link_order
8208 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8209 == bfd_target_elf_flavour)
8210 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8212 if (! sub->output_has_begun)
8214 if (! elf_link_input_bfd (&finfo, sub))
8215 goto error_return;
8216 sub->output_has_begun = TRUE;
8219 else if (p->type == bfd_section_reloc_link_order
8220 || p->type == bfd_symbol_reloc_link_order)
8222 if (! elf_reloc_link_order (abfd, info, o, p))
8223 goto error_return;
8225 else
8227 if (! _bfd_default_link_order (abfd, info, o, p))
8228 goto error_return;
8233 /* Output any global symbols that got converted to local in a
8234 version script or due to symbol visibility. We do this in a
8235 separate step since ELF requires all local symbols to appear
8236 prior to any global symbols. FIXME: We should only do this if
8237 some global symbols were, in fact, converted to become local.
8238 FIXME: Will this work correctly with the Irix 5 linker? */
8239 eoinfo.failed = FALSE;
8240 eoinfo.finfo = &finfo;
8241 eoinfo.localsyms = TRUE;
8242 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8243 &eoinfo);
8244 if (eoinfo.failed)
8245 return FALSE;
8247 /* That wrote out all the local symbols. Finish up the symbol table
8248 with the global symbols. Even if we want to strip everything we
8249 can, we still need to deal with those global symbols that got
8250 converted to local in a version script. */
8252 /* The sh_info field records the index of the first non local symbol. */
8253 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8255 if (dynamic
8256 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8258 Elf_Internal_Sym sym;
8259 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8260 long last_local = 0;
8262 /* Write out the section symbols for the output sections. */
8263 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
8265 asection *s;
8267 sym.st_size = 0;
8268 sym.st_name = 0;
8269 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8270 sym.st_other = 0;
8272 for (s = abfd->sections; s != NULL; s = s->next)
8274 int indx;
8275 bfd_byte *dest;
8276 long dynindx;
8278 dynindx = elf_section_data (s)->dynindx;
8279 if (dynindx <= 0)
8280 continue;
8281 indx = elf_section_data (s)->this_idx;
8282 BFD_ASSERT (indx > 0);
8283 sym.st_shndx = indx;
8284 sym.st_value = s->vma;
8285 dest = dynsym + dynindx * bed->s->sizeof_sym;
8286 if (last_local < dynindx)
8287 last_local = dynindx;
8288 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8292 /* Write out the local dynsyms. */
8293 if (elf_hash_table (info)->dynlocal)
8295 struct elf_link_local_dynamic_entry *e;
8296 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8298 asection *s;
8299 bfd_byte *dest;
8301 sym.st_size = e->isym.st_size;
8302 sym.st_other = e->isym.st_other;
8304 /* Copy the internal symbol as is.
8305 Note that we saved a word of storage and overwrote
8306 the original st_name with the dynstr_index. */
8307 sym = e->isym;
8309 if (e->isym.st_shndx != SHN_UNDEF
8310 && (e->isym.st_shndx < SHN_LORESERVE
8311 || e->isym.st_shndx > SHN_HIRESERVE))
8313 s = bfd_section_from_elf_index (e->input_bfd,
8314 e->isym.st_shndx);
8316 sym.st_shndx =
8317 elf_section_data (s->output_section)->this_idx;
8318 sym.st_value = (s->output_section->vma
8319 + s->output_offset
8320 + e->isym.st_value);
8323 if (last_local < e->dynindx)
8324 last_local = e->dynindx;
8326 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8327 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8331 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8332 last_local + 1;
8335 /* We get the global symbols from the hash table. */
8336 eoinfo.failed = FALSE;
8337 eoinfo.localsyms = FALSE;
8338 eoinfo.finfo = &finfo;
8339 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8340 &eoinfo);
8341 if (eoinfo.failed)
8342 return FALSE;
8344 /* If backend needs to output some symbols not present in the hash
8345 table, do it now. */
8346 if (bed->elf_backend_output_arch_syms)
8348 typedef bfd_boolean (*out_sym_func)
8349 (void *, const char *, Elf_Internal_Sym *, asection *,
8350 struct elf_link_hash_entry *);
8352 if (! ((*bed->elf_backend_output_arch_syms)
8353 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8354 return FALSE;
8357 /* Flush all symbols to the file. */
8358 if (! elf_link_flush_output_syms (&finfo, bed))
8359 return FALSE;
8361 /* Now we know the size of the symtab section. */
8362 off += symtab_hdr->sh_size;
8364 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8365 if (symtab_shndx_hdr->sh_name != 0)
8367 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8368 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8369 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8370 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8371 symtab_shndx_hdr->sh_size = amt;
8373 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8374 off, TRUE);
8376 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8377 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8378 return FALSE;
8382 /* Finish up and write out the symbol string table (.strtab)
8383 section. */
8384 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8385 /* sh_name was set in prep_headers. */
8386 symstrtab_hdr->sh_type = SHT_STRTAB;
8387 symstrtab_hdr->sh_flags = 0;
8388 symstrtab_hdr->sh_addr = 0;
8389 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8390 symstrtab_hdr->sh_entsize = 0;
8391 symstrtab_hdr->sh_link = 0;
8392 symstrtab_hdr->sh_info = 0;
8393 /* sh_offset is set just below. */
8394 symstrtab_hdr->sh_addralign = 1;
8396 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8397 elf_tdata (abfd)->next_file_pos = off;
8399 if (bfd_get_symcount (abfd) > 0)
8401 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8402 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8403 return FALSE;
8406 /* Adjust the relocs to have the correct symbol indices. */
8407 for (o = abfd->sections; o != NULL; o = o->next)
8409 if ((o->flags & SEC_RELOC) == 0)
8410 continue;
8412 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8413 elf_section_data (o)->rel_count,
8414 elf_section_data (o)->rel_hashes);
8415 if (elf_section_data (o)->rel_hdr2 != NULL)
8416 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8417 elf_section_data (o)->rel_count2,
8418 (elf_section_data (o)->rel_hashes
8419 + elf_section_data (o)->rel_count));
8421 /* Set the reloc_count field to 0 to prevent write_relocs from
8422 trying to swap the relocs out itself. */
8423 o->reloc_count = 0;
8426 if (dynamic && info->combreloc && dynobj != NULL)
8427 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8429 /* If we are linking against a dynamic object, or generating a
8430 shared library, finish up the dynamic linking information. */
8431 if (dynamic)
8433 bfd_byte *dyncon, *dynconend;
8435 /* Fix up .dynamic entries. */
8436 o = bfd_get_section_by_name (dynobj, ".dynamic");
8437 BFD_ASSERT (o != NULL);
8439 dyncon = o->contents;
8440 dynconend = o->contents + o->size;
8441 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8443 Elf_Internal_Dyn dyn;
8444 const char *name;
8445 unsigned int type;
8447 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8449 switch (dyn.d_tag)
8451 default:
8452 continue;
8453 case DT_NULL:
8454 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8456 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8458 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8459 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8460 default: continue;
8462 dyn.d_un.d_val = relativecount;
8463 relativecount = 0;
8464 break;
8466 continue;
8468 case DT_INIT:
8469 name = info->init_function;
8470 goto get_sym;
8471 case DT_FINI:
8472 name = info->fini_function;
8473 get_sym:
8475 struct elf_link_hash_entry *h;
8477 h = elf_link_hash_lookup (elf_hash_table (info), name,
8478 FALSE, FALSE, TRUE);
8479 if (h != NULL
8480 && (h->root.type == bfd_link_hash_defined
8481 || h->root.type == bfd_link_hash_defweak))
8483 dyn.d_un.d_val = h->root.u.def.value;
8484 o = h->root.u.def.section;
8485 if (o->output_section != NULL)
8486 dyn.d_un.d_val += (o->output_section->vma
8487 + o->output_offset);
8488 else
8490 /* The symbol is imported from another shared
8491 library and does not apply to this one. */
8492 dyn.d_un.d_val = 0;
8494 break;
8497 continue;
8499 case DT_PREINIT_ARRAYSZ:
8500 name = ".preinit_array";
8501 goto get_size;
8502 case DT_INIT_ARRAYSZ:
8503 name = ".init_array";
8504 goto get_size;
8505 case DT_FINI_ARRAYSZ:
8506 name = ".fini_array";
8507 get_size:
8508 o = bfd_get_section_by_name (abfd, name);
8509 if (o == NULL)
8511 (*_bfd_error_handler)
8512 (_("%B: could not find output section %s"), abfd, name);
8513 goto error_return;
8515 if (o->size == 0)
8516 (*_bfd_error_handler)
8517 (_("warning: %s section has zero size"), name);
8518 dyn.d_un.d_val = o->size;
8519 break;
8521 case DT_PREINIT_ARRAY:
8522 name = ".preinit_array";
8523 goto get_vma;
8524 case DT_INIT_ARRAY:
8525 name = ".init_array";
8526 goto get_vma;
8527 case DT_FINI_ARRAY:
8528 name = ".fini_array";
8529 goto get_vma;
8531 case DT_HASH:
8532 name = ".hash";
8533 goto get_vma;
8534 case DT_STRTAB:
8535 name = ".dynstr";
8536 goto get_vma;
8537 case DT_SYMTAB:
8538 name = ".dynsym";
8539 goto get_vma;
8540 case DT_VERDEF:
8541 name = ".gnu.version_d";
8542 goto get_vma;
8543 case DT_VERNEED:
8544 name = ".gnu.version_r";
8545 goto get_vma;
8546 case DT_VERSYM:
8547 name = ".gnu.version";
8548 get_vma:
8549 o = bfd_get_section_by_name (abfd, name);
8550 if (o == NULL)
8552 (*_bfd_error_handler)
8553 (_("%B: could not find output section %s"), abfd, name);
8554 goto error_return;
8556 dyn.d_un.d_ptr = o->vma;
8557 break;
8559 case DT_REL:
8560 case DT_RELA:
8561 case DT_RELSZ:
8562 case DT_RELASZ:
8563 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8564 type = SHT_REL;
8565 else
8566 type = SHT_RELA;
8567 dyn.d_un.d_val = 0;
8568 for (i = 1; i < elf_numsections (abfd); i++)
8570 Elf_Internal_Shdr *hdr;
8572 hdr = elf_elfsections (abfd)[i];
8573 if (hdr->sh_type == type
8574 && (hdr->sh_flags & SHF_ALLOC) != 0)
8576 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8577 dyn.d_un.d_val += hdr->sh_size;
8578 else
8580 if (dyn.d_un.d_val == 0
8581 || hdr->sh_addr < dyn.d_un.d_val)
8582 dyn.d_un.d_val = hdr->sh_addr;
8586 break;
8588 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8592 /* If we have created any dynamic sections, then output them. */
8593 if (dynobj != NULL)
8595 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8596 goto error_return;
8598 for (o = dynobj->sections; o != NULL; o = o->next)
8600 if ((o->flags & SEC_HAS_CONTENTS) == 0
8601 || o->size == 0
8602 || o->output_section == bfd_abs_section_ptr)
8603 continue;
8604 if ((o->flags & SEC_LINKER_CREATED) == 0)
8606 /* At this point, we are only interested in sections
8607 created by _bfd_elf_link_create_dynamic_sections. */
8608 continue;
8610 if (elf_hash_table (info)->stab_info.stabstr == o)
8611 continue;
8612 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8613 continue;
8614 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8615 != SHT_STRTAB)
8616 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8618 if (! bfd_set_section_contents (abfd, o->output_section,
8619 o->contents,
8620 (file_ptr) o->output_offset,
8621 o->size))
8622 goto error_return;
8624 else
8626 /* The contents of the .dynstr section are actually in a
8627 stringtab. */
8628 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8629 if (bfd_seek (abfd, off, SEEK_SET) != 0
8630 || ! _bfd_elf_strtab_emit (abfd,
8631 elf_hash_table (info)->dynstr))
8632 goto error_return;
8637 if (info->relocatable)
8639 bfd_boolean failed = FALSE;
8641 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8642 if (failed)
8643 goto error_return;
8646 /* If we have optimized stabs strings, output them. */
8647 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8649 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8650 goto error_return;
8653 if (info->eh_frame_hdr)
8655 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8656 goto error_return;
8659 if (finfo.symstrtab != NULL)
8660 _bfd_stringtab_free (finfo.symstrtab);
8661 if (finfo.contents != NULL)
8662 free (finfo.contents);
8663 if (finfo.external_relocs != NULL)
8664 free (finfo.external_relocs);
8665 if (finfo.internal_relocs != NULL)
8666 free (finfo.internal_relocs);
8667 if (finfo.external_syms != NULL)
8668 free (finfo.external_syms);
8669 if (finfo.locsym_shndx != NULL)
8670 free (finfo.locsym_shndx);
8671 if (finfo.internal_syms != NULL)
8672 free (finfo.internal_syms);
8673 if (finfo.indices != NULL)
8674 free (finfo.indices);
8675 if (finfo.sections != NULL)
8676 free (finfo.sections);
8677 if (finfo.symbuf != NULL)
8678 free (finfo.symbuf);
8679 if (finfo.symshndxbuf != NULL)
8680 free (finfo.symshndxbuf);
8681 for (o = abfd->sections; o != NULL; o = o->next)
8683 if ((o->flags & SEC_RELOC) != 0
8684 && elf_section_data (o)->rel_hashes != NULL)
8685 free (elf_section_data (o)->rel_hashes);
8688 elf_tdata (abfd)->linker = TRUE;
8690 return TRUE;
8692 error_return:
8693 if (finfo.symstrtab != NULL)
8694 _bfd_stringtab_free (finfo.symstrtab);
8695 if (finfo.contents != NULL)
8696 free (finfo.contents);
8697 if (finfo.external_relocs != NULL)
8698 free (finfo.external_relocs);
8699 if (finfo.internal_relocs != NULL)
8700 free (finfo.internal_relocs);
8701 if (finfo.external_syms != NULL)
8702 free (finfo.external_syms);
8703 if (finfo.locsym_shndx != NULL)
8704 free (finfo.locsym_shndx);
8705 if (finfo.internal_syms != NULL)
8706 free (finfo.internal_syms);
8707 if (finfo.indices != NULL)
8708 free (finfo.indices);
8709 if (finfo.sections != NULL)
8710 free (finfo.sections);
8711 if (finfo.symbuf != NULL)
8712 free (finfo.symbuf);
8713 if (finfo.symshndxbuf != NULL)
8714 free (finfo.symshndxbuf);
8715 for (o = abfd->sections; o != NULL; o = o->next)
8717 if ((o->flags & SEC_RELOC) != 0
8718 && elf_section_data (o)->rel_hashes != NULL)
8719 free (elf_section_data (o)->rel_hashes);
8722 return FALSE;
8725 /* Garbage collect unused sections. */
8727 /* The mark phase of garbage collection. For a given section, mark
8728 it and any sections in this section's group, and all the sections
8729 which define symbols to which it refers. */
8731 typedef asection * (*gc_mark_hook_fn)
8732 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8733 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8735 bfd_boolean
8736 _bfd_elf_gc_mark (struct bfd_link_info *info,
8737 asection *sec,
8738 gc_mark_hook_fn gc_mark_hook)
8740 bfd_boolean ret;
8741 bfd_boolean is_eh;
8742 asection *group_sec;
8744 sec->gc_mark = 1;
8746 /* Mark all the sections in the group. */
8747 group_sec = elf_section_data (sec)->next_in_group;
8748 if (group_sec && !group_sec->gc_mark)
8749 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
8750 return FALSE;
8752 /* Look through the section relocs. */
8753 ret = TRUE;
8754 is_eh = strcmp (sec->name, ".eh_frame") == 0;
8755 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8757 Elf_Internal_Rela *relstart, *rel, *relend;
8758 Elf_Internal_Shdr *symtab_hdr;
8759 struct elf_link_hash_entry **sym_hashes;
8760 size_t nlocsyms;
8761 size_t extsymoff;
8762 bfd *input_bfd = sec->owner;
8763 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8764 Elf_Internal_Sym *isym = NULL;
8765 int r_sym_shift;
8767 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8768 sym_hashes = elf_sym_hashes (input_bfd);
8770 /* Read the local symbols. */
8771 if (elf_bad_symtab (input_bfd))
8773 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8774 extsymoff = 0;
8776 else
8777 extsymoff = nlocsyms = symtab_hdr->sh_info;
8779 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8780 if (isym == NULL && nlocsyms != 0)
8782 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8783 NULL, NULL, NULL);
8784 if (isym == NULL)
8785 return FALSE;
8788 /* Read the relocations. */
8789 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8790 info->keep_memory);
8791 if (relstart == NULL)
8793 ret = FALSE;
8794 goto out1;
8796 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8798 if (bed->s->arch_size == 32)
8799 r_sym_shift = 8;
8800 else
8801 r_sym_shift = 32;
8803 for (rel = relstart; rel < relend; rel++)
8805 unsigned long r_symndx;
8806 asection *rsec;
8807 struct elf_link_hash_entry *h;
8809 r_symndx = rel->r_info >> r_sym_shift;
8810 if (r_symndx == 0)
8811 continue;
8813 if (r_symndx >= nlocsyms
8814 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8816 h = sym_hashes[r_symndx - extsymoff];
8817 while (h->root.type == bfd_link_hash_indirect
8818 || h->root.type == bfd_link_hash_warning)
8819 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8820 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8822 else
8824 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8827 if (rsec && !rsec->gc_mark)
8829 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8830 rsec->gc_mark = 1;
8831 else if (is_eh)
8832 rsec->gc_mark_from_eh = 1;
8833 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
8835 ret = FALSE;
8836 goto out2;
8841 out2:
8842 if (elf_section_data (sec)->relocs != relstart)
8843 free (relstart);
8844 out1:
8845 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8847 if (! info->keep_memory)
8848 free (isym);
8849 else
8850 symtab_hdr->contents = (unsigned char *) isym;
8854 return ret;
8857 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8859 static bfd_boolean
8860 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
8862 int *idx = idxptr;
8864 if (h->root.type == bfd_link_hash_warning)
8865 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8867 if (h->dynindx != -1
8868 && ((h->root.type != bfd_link_hash_defined
8869 && h->root.type != bfd_link_hash_defweak)
8870 || h->root.u.def.section->gc_mark))
8871 h->dynindx = (*idx)++;
8873 return TRUE;
8876 /* The sweep phase of garbage collection. Remove all garbage sections. */
8878 typedef bfd_boolean (*gc_sweep_hook_fn)
8879 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8881 static bfd_boolean
8882 elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
8884 bfd *sub;
8886 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8888 asection *o;
8890 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8891 continue;
8893 for (o = sub->sections; o != NULL; o = o->next)
8895 /* Keep debug and special sections. */
8896 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
8897 || (o->flags & (SEC_ALLOC | SEC_LOAD)) == 0)
8898 o->gc_mark = 1;
8900 if (o->gc_mark)
8901 continue;
8903 /* Skip sweeping sections already excluded. */
8904 if (o->flags & SEC_EXCLUDE)
8905 continue;
8907 /* Since this is early in the link process, it is simple
8908 to remove a section from the output. */
8909 o->flags |= SEC_EXCLUDE;
8911 /* But we also have to update some of the relocation
8912 info we collected before. */
8913 if (gc_sweep_hook
8914 && (o->flags & SEC_RELOC) != 0
8915 && o->reloc_count > 0
8916 && !bfd_is_abs_section (o->output_section))
8918 Elf_Internal_Rela *internal_relocs;
8919 bfd_boolean r;
8921 internal_relocs
8922 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8923 info->keep_memory);
8924 if (internal_relocs == NULL)
8925 return FALSE;
8927 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8929 if (elf_section_data (o)->relocs != internal_relocs)
8930 free (internal_relocs);
8932 if (!r)
8933 return FALSE;
8938 /* Remove the symbols that were in the swept sections from the dynamic
8939 symbol table. GCFIXME: Anyone know how to get them out of the
8940 static symbol table as well? */
8942 int i = 0;
8944 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
8946 elf_hash_table (info)->dynsymcount = i;
8949 return TRUE;
8952 /* Propagate collected vtable information. This is called through
8953 elf_link_hash_traverse. */
8955 static bfd_boolean
8956 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
8958 if (h->root.type == bfd_link_hash_warning)
8959 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8961 /* Those that are not vtables. */
8962 if (h->vtable == NULL || h->vtable->parent == NULL)
8963 return TRUE;
8965 /* Those vtables that do not have parents, we cannot merge. */
8966 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
8967 return TRUE;
8969 /* If we've already been done, exit. */
8970 if (h->vtable->used && h->vtable->used[-1])
8971 return TRUE;
8973 /* Make sure the parent's table is up to date. */
8974 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
8976 if (h->vtable->used == NULL)
8978 /* None of this table's entries were referenced. Re-use the
8979 parent's table. */
8980 h->vtable->used = h->vtable->parent->vtable->used;
8981 h->vtable->size = h->vtable->parent->vtable->size;
8983 else
8985 size_t n;
8986 bfd_boolean *cu, *pu;
8988 /* Or the parent's entries into ours. */
8989 cu = h->vtable->used;
8990 cu[-1] = TRUE;
8991 pu = h->vtable->parent->vtable->used;
8992 if (pu != NULL)
8994 const struct elf_backend_data *bed;
8995 unsigned int log_file_align;
8997 bed = get_elf_backend_data (h->root.u.def.section->owner);
8998 log_file_align = bed->s->log_file_align;
8999 n = h->vtable->parent->vtable->size >> log_file_align;
9000 while (n--)
9002 if (*pu)
9003 *cu = TRUE;
9004 pu++;
9005 cu++;
9010 return TRUE;
9013 static bfd_boolean
9014 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
9016 asection *sec;
9017 bfd_vma hstart, hend;
9018 Elf_Internal_Rela *relstart, *relend, *rel;
9019 const struct elf_backend_data *bed;
9020 unsigned int log_file_align;
9022 if (h->root.type == bfd_link_hash_warning)
9023 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9025 /* Take care of both those symbols that do not describe vtables as
9026 well as those that are not loaded. */
9027 if (h->vtable == NULL || h->vtable->parent == NULL)
9028 return TRUE;
9030 BFD_ASSERT (h->root.type == bfd_link_hash_defined
9031 || h->root.type == bfd_link_hash_defweak);
9033 sec = h->root.u.def.section;
9034 hstart = h->root.u.def.value;
9035 hend = hstart + h->size;
9037 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
9038 if (!relstart)
9039 return *(bfd_boolean *) okp = FALSE;
9040 bed = get_elf_backend_data (sec->owner);
9041 log_file_align = bed->s->log_file_align;
9043 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
9045 for (rel = relstart; rel < relend; ++rel)
9046 if (rel->r_offset >= hstart && rel->r_offset < hend)
9048 /* If the entry is in use, do nothing. */
9049 if (h->vtable->used
9050 && (rel->r_offset - hstart) < h->vtable->size)
9052 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
9053 if (h->vtable->used[entry])
9054 continue;
9056 /* Otherwise, kill it. */
9057 rel->r_offset = rel->r_info = rel->r_addend = 0;
9060 return TRUE;
9063 /* Mark sections containing dynamically referenced symbols. When
9064 building shared libraries, we must assume that any visible symbol is
9065 referenced. */
9067 static bfd_boolean
9068 elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
9070 struct bfd_link_info *info = (struct bfd_link_info *) inf;
9072 if (h->root.type == bfd_link_hash_warning)
9073 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9075 if ((h->root.type == bfd_link_hash_defined
9076 || h->root.type == bfd_link_hash_defweak)
9077 && (h->ref_dynamic
9078 || (info->shared
9079 && h->def_regular
9080 && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
9081 && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN)))
9082 h->root.u.def.section->flags |= SEC_KEEP;
9084 return TRUE;
9087 /* Do mark and sweep of unused sections. */
9089 bfd_boolean
9090 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
9092 bfd_boolean ok = TRUE;
9093 bfd *sub;
9094 asection * (*gc_mark_hook)
9095 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9096 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
9098 if (!get_elf_backend_data (abfd)->can_gc_sections
9099 || info->relocatable
9100 || info->emitrelocations
9101 || !is_elf_hash_table (info->hash))
9103 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
9104 return TRUE;
9107 /* Apply transitive closure to the vtable entry usage info. */
9108 elf_link_hash_traverse (elf_hash_table (info),
9109 elf_gc_propagate_vtable_entries_used,
9110 &ok);
9111 if (!ok)
9112 return FALSE;
9114 /* Kill the vtable relocations that were not used. */
9115 elf_link_hash_traverse (elf_hash_table (info),
9116 elf_gc_smash_unused_vtentry_relocs,
9117 &ok);
9118 if (!ok)
9119 return FALSE;
9121 /* Mark dynamically referenced symbols. */
9122 if (elf_hash_table (info)->dynamic_sections_created)
9123 elf_link_hash_traverse (elf_hash_table (info),
9124 elf_gc_mark_dynamic_ref_symbol,
9125 info);
9127 /* Grovel through relocs to find out who stays ... */
9128 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
9129 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9131 asection *o;
9133 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9134 continue;
9136 for (o = sub->sections; o != NULL; o = o->next)
9137 if ((o->flags & SEC_KEEP) != 0 && !o->gc_mark)
9138 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9139 return FALSE;
9142 /* ... again for sections marked from eh_frame. */
9143 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9145 asection *o;
9147 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9148 continue;
9150 /* Keep .gcc_except_table.* if the associated .text.* is
9151 marked. This isn't very nice, but the proper solution,
9152 splitting .eh_frame up and using comdat doesn't pan out
9153 easily due to needing special relocs to handle the
9154 difference of two symbols in separate sections.
9155 Don't keep code sections referenced by .eh_frame. */
9156 for (o = sub->sections; o != NULL; o = o->next)
9157 if (!o->gc_mark && o->gc_mark_from_eh && (o->flags & SEC_CODE) == 0)
9159 if (strncmp (o->name, ".gcc_except_table.", 18) == 0)
9161 unsigned long len;
9162 char *fn_name;
9163 asection *fn_text;
9165 len = strlen (o->name + 18) + 1;
9166 fn_name = bfd_malloc (len + 6);
9167 if (fn_name == NULL)
9168 return FALSE;
9169 memcpy (fn_name, ".text.", 6);
9170 memcpy (fn_name + 6, o->name + 18, len);
9171 fn_text = bfd_get_section_by_name (sub, fn_name);
9172 free (fn_name);
9173 if (fn_text == NULL || !fn_text->gc_mark)
9174 continue;
9177 /* If not using specially named exception table section,
9178 then keep whatever we are using. */
9179 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9180 return FALSE;
9184 /* ... and mark SEC_EXCLUDE for those that go. */
9185 if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
9186 return FALSE;
9188 return TRUE;
9191 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9193 bfd_boolean
9194 bfd_elf_gc_record_vtinherit (bfd *abfd,
9195 asection *sec,
9196 struct elf_link_hash_entry *h,
9197 bfd_vma offset)
9199 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9200 struct elf_link_hash_entry **search, *child;
9201 bfd_size_type extsymcount;
9202 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9204 /* The sh_info field of the symtab header tells us where the
9205 external symbols start. We don't care about the local symbols at
9206 this point. */
9207 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9208 if (!elf_bad_symtab (abfd))
9209 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9211 sym_hashes = elf_sym_hashes (abfd);
9212 sym_hashes_end = sym_hashes + extsymcount;
9214 /* Hunt down the child symbol, which is in this section at the same
9215 offset as the relocation. */
9216 for (search = sym_hashes; search != sym_hashes_end; ++search)
9218 if ((child = *search) != NULL
9219 && (child->root.type == bfd_link_hash_defined
9220 || child->root.type == bfd_link_hash_defweak)
9221 && child->root.u.def.section == sec
9222 && child->root.u.def.value == offset)
9223 goto win;
9226 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9227 abfd, sec, (unsigned long) offset);
9228 bfd_set_error (bfd_error_invalid_operation);
9229 return FALSE;
9231 win:
9232 if (!child->vtable)
9234 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9235 if (!child->vtable)
9236 return FALSE;
9238 if (!h)
9240 /* This *should* only be the absolute section. It could potentially
9241 be that someone has defined a non-global vtable though, which
9242 would be bad. It isn't worth paging in the local symbols to be
9243 sure though; that case should simply be handled by the assembler. */
9245 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9247 else
9248 child->vtable->parent = h;
9250 return TRUE;
9253 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9255 bfd_boolean
9256 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9257 asection *sec ATTRIBUTE_UNUSED,
9258 struct elf_link_hash_entry *h,
9259 bfd_vma addend)
9261 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9262 unsigned int log_file_align = bed->s->log_file_align;
9264 if (!h->vtable)
9266 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9267 if (!h->vtable)
9268 return FALSE;
9271 if (addend >= h->vtable->size)
9273 size_t size, bytes, file_align;
9274 bfd_boolean *ptr = h->vtable->used;
9276 /* While the symbol is undefined, we have to be prepared to handle
9277 a zero size. */
9278 file_align = 1 << log_file_align;
9279 if (h->root.type == bfd_link_hash_undefined)
9280 size = addend + file_align;
9281 else
9283 size = h->size;
9284 if (addend >= size)
9286 /* Oops! We've got a reference past the defined end of
9287 the table. This is probably a bug -- shall we warn? */
9288 size = addend + file_align;
9291 size = (size + file_align - 1) & -file_align;
9293 /* Allocate one extra entry for use as a "done" flag for the
9294 consolidation pass. */
9295 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9297 if (ptr)
9299 ptr = bfd_realloc (ptr - 1, bytes);
9301 if (ptr != NULL)
9303 size_t oldbytes;
9305 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9306 * sizeof (bfd_boolean));
9307 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9310 else
9311 ptr = bfd_zmalloc (bytes);
9313 if (ptr == NULL)
9314 return FALSE;
9316 /* And arrange for that done flag to be at index -1. */
9317 h->vtable->used = ptr + 1;
9318 h->vtable->size = size;
9321 h->vtable->used[addend >> log_file_align] = TRUE;
9323 return TRUE;
9326 struct alloc_got_off_arg {
9327 bfd_vma gotoff;
9328 unsigned int got_elt_size;
9331 /* We need a special top-level link routine to convert got reference counts
9332 to real got offsets. */
9334 static bfd_boolean
9335 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
9337 struct alloc_got_off_arg *gofarg = arg;
9339 if (h->root.type == bfd_link_hash_warning)
9340 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9342 if (h->got.refcount > 0)
9344 h->got.offset = gofarg->gotoff;
9345 gofarg->gotoff += gofarg->got_elt_size;
9347 else
9348 h->got.offset = (bfd_vma) -1;
9350 return TRUE;
9353 /* And an accompanying bit to work out final got entry offsets once
9354 we're done. Should be called from final_link. */
9356 bfd_boolean
9357 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
9358 struct bfd_link_info *info)
9360 bfd *i;
9361 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9362 bfd_vma gotoff;
9363 unsigned int got_elt_size = bed->s->arch_size / 8;
9364 struct alloc_got_off_arg gofarg;
9366 if (! is_elf_hash_table (info->hash))
9367 return FALSE;
9369 /* The GOT offset is relative to the .got section, but the GOT header is
9370 put into the .got.plt section, if the backend uses it. */
9371 if (bed->want_got_plt)
9372 gotoff = 0;
9373 else
9374 gotoff = bed->got_header_size;
9376 /* Do the local .got entries first. */
9377 for (i = info->input_bfds; i; i = i->link_next)
9379 bfd_signed_vma *local_got;
9380 bfd_size_type j, locsymcount;
9381 Elf_Internal_Shdr *symtab_hdr;
9383 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
9384 continue;
9386 local_got = elf_local_got_refcounts (i);
9387 if (!local_got)
9388 continue;
9390 symtab_hdr = &elf_tdata (i)->symtab_hdr;
9391 if (elf_bad_symtab (i))
9392 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9393 else
9394 locsymcount = symtab_hdr->sh_info;
9396 for (j = 0; j < locsymcount; ++j)
9398 if (local_got[j] > 0)
9400 local_got[j] = gotoff;
9401 gotoff += got_elt_size;
9403 else
9404 local_got[j] = (bfd_vma) -1;
9408 /* Then the global .got entries. .plt refcounts are handled by
9409 adjust_dynamic_symbol */
9410 gofarg.gotoff = gotoff;
9411 gofarg.got_elt_size = got_elt_size;
9412 elf_link_hash_traverse (elf_hash_table (info),
9413 elf_gc_allocate_got_offsets,
9414 &gofarg);
9415 return TRUE;
9418 /* Many folk need no more in the way of final link than this, once
9419 got entry reference counting is enabled. */
9421 bfd_boolean
9422 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
9424 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
9425 return FALSE;
9427 /* Invoke the regular ELF backend linker to do all the work. */
9428 return bfd_elf_final_link (abfd, info);
9431 bfd_boolean
9432 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
9434 struct elf_reloc_cookie *rcookie = cookie;
9436 if (rcookie->bad_symtab)
9437 rcookie->rel = rcookie->rels;
9439 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9441 unsigned long r_symndx;
9443 if (! rcookie->bad_symtab)
9444 if (rcookie->rel->r_offset > offset)
9445 return FALSE;
9446 if (rcookie->rel->r_offset != offset)
9447 continue;
9449 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9450 if (r_symndx == SHN_UNDEF)
9451 return TRUE;
9453 if (r_symndx >= rcookie->locsymcount
9454 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9456 struct elf_link_hash_entry *h;
9458 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9460 while (h->root.type == bfd_link_hash_indirect
9461 || h->root.type == bfd_link_hash_warning)
9462 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9464 if ((h->root.type == bfd_link_hash_defined
9465 || h->root.type == bfd_link_hash_defweak)
9466 && elf_discarded_section (h->root.u.def.section))
9467 return TRUE;
9468 else
9469 return FALSE;
9471 else
9473 /* It's not a relocation against a global symbol,
9474 but it could be a relocation against a local
9475 symbol for a discarded section. */
9476 asection *isec;
9477 Elf_Internal_Sym *isym;
9479 /* Need to: get the symbol; get the section. */
9480 isym = &rcookie->locsyms[r_symndx];
9481 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9483 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9484 if (isec != NULL && elf_discarded_section (isec))
9485 return TRUE;
9488 return FALSE;
9490 return FALSE;
9493 /* Discard unneeded references to discarded sections.
9494 Returns TRUE if any section's size was changed. */
9495 /* This function assumes that the relocations are in sorted order,
9496 which is true for all known assemblers. */
9498 bfd_boolean
9499 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9501 struct elf_reloc_cookie cookie;
9502 asection *stab, *eh;
9503 Elf_Internal_Shdr *symtab_hdr;
9504 const struct elf_backend_data *bed;
9505 bfd *abfd;
9506 unsigned int count;
9507 bfd_boolean ret = FALSE;
9509 if (info->traditional_format
9510 || !is_elf_hash_table (info->hash))
9511 return FALSE;
9513 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9515 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9516 continue;
9518 bed = get_elf_backend_data (abfd);
9520 if ((abfd->flags & DYNAMIC) != 0)
9521 continue;
9523 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9524 if (info->relocatable
9525 || (eh != NULL
9526 && (eh->size == 0
9527 || bfd_is_abs_section (eh->output_section))))
9528 eh = NULL;
9530 stab = bfd_get_section_by_name (abfd, ".stab");
9531 if (stab != NULL
9532 && (stab->size == 0
9533 || bfd_is_abs_section (stab->output_section)
9534 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9535 stab = NULL;
9537 if (stab == NULL
9538 && eh == NULL
9539 && bed->elf_backend_discard_info == NULL)
9540 continue;
9542 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9543 cookie.abfd = abfd;
9544 cookie.sym_hashes = elf_sym_hashes (abfd);
9545 cookie.bad_symtab = elf_bad_symtab (abfd);
9546 if (cookie.bad_symtab)
9548 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9549 cookie.extsymoff = 0;
9551 else
9553 cookie.locsymcount = symtab_hdr->sh_info;
9554 cookie.extsymoff = symtab_hdr->sh_info;
9557 if (bed->s->arch_size == 32)
9558 cookie.r_sym_shift = 8;
9559 else
9560 cookie.r_sym_shift = 32;
9562 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9563 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9565 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9566 cookie.locsymcount, 0,
9567 NULL, NULL, NULL);
9568 if (cookie.locsyms == NULL)
9569 return FALSE;
9572 if (stab != NULL)
9574 cookie.rels = NULL;
9575 count = stab->reloc_count;
9576 if (count != 0)
9577 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9578 info->keep_memory);
9579 if (cookie.rels != NULL)
9581 cookie.rel = cookie.rels;
9582 cookie.relend = cookie.rels;
9583 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9584 if (_bfd_discard_section_stabs (abfd, stab,
9585 elf_section_data (stab)->sec_info,
9586 bfd_elf_reloc_symbol_deleted_p,
9587 &cookie))
9588 ret = TRUE;
9589 if (elf_section_data (stab)->relocs != cookie.rels)
9590 free (cookie.rels);
9594 if (eh != NULL)
9596 cookie.rels = NULL;
9597 count = eh->reloc_count;
9598 if (count != 0)
9599 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9600 info->keep_memory);
9601 cookie.rel = cookie.rels;
9602 cookie.relend = cookie.rels;
9603 if (cookie.rels != NULL)
9604 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9606 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9607 bfd_elf_reloc_symbol_deleted_p,
9608 &cookie))
9609 ret = TRUE;
9611 if (cookie.rels != NULL
9612 && elf_section_data (eh)->relocs != cookie.rels)
9613 free (cookie.rels);
9616 if (bed->elf_backend_discard_info != NULL
9617 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9618 ret = TRUE;
9620 if (cookie.locsyms != NULL
9621 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9623 if (! info->keep_memory)
9624 free (cookie.locsyms);
9625 else
9626 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9630 if (info->eh_frame_hdr
9631 && !info->relocatable
9632 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9633 ret = TRUE;
9635 return ret;
9638 void
9639 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9641 flagword flags;
9642 const char *name, *p;
9643 struct bfd_section_already_linked *l;
9644 struct bfd_section_already_linked_hash_entry *already_linked_list;
9645 asection *group;
9647 /* A single member comdat group section may be discarded by a
9648 linkonce section. See below. */
9649 if (sec->output_section == bfd_abs_section_ptr)
9650 return;
9652 flags = sec->flags;
9654 /* Check if it belongs to a section group. */
9655 group = elf_sec_group (sec);
9657 /* Return if it isn't a linkonce section nor a member of a group. A
9658 comdat group section also has SEC_LINK_ONCE set. */
9659 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9660 return;
9662 if (group)
9664 /* If this is the member of a single member comdat group, check if
9665 the group should be discarded. */
9666 if (elf_next_in_group (sec) == sec
9667 && (group->flags & SEC_LINK_ONCE) != 0)
9668 sec = group;
9669 else
9670 return;
9673 /* FIXME: When doing a relocatable link, we may have trouble
9674 copying relocations in other sections that refer to local symbols
9675 in the section being discarded. Those relocations will have to
9676 be converted somehow; as of this writing I'm not sure that any of
9677 the backends handle that correctly.
9679 It is tempting to instead not discard link once sections when
9680 doing a relocatable link (technically, they should be discarded
9681 whenever we are building constructors). However, that fails,
9682 because the linker winds up combining all the link once sections
9683 into a single large link once section, which defeats the purpose
9684 of having link once sections in the first place.
9686 Also, not merging link once sections in a relocatable link
9687 causes trouble for MIPS ELF, which relies on link once semantics
9688 to handle the .reginfo section correctly. */
9690 name = bfd_get_section_name (abfd, sec);
9692 if (strncmp (name, ".gnu.linkonce.", sizeof (".gnu.linkonce.") - 1) == 0
9693 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
9694 p++;
9695 else
9696 p = name;
9698 already_linked_list = bfd_section_already_linked_table_lookup (p);
9700 for (l = already_linked_list->entry; l != NULL; l = l->next)
9702 /* We may have 3 different sections on the list: group section,
9703 comdat section and linkonce section. SEC may be a linkonce or
9704 group section. We match a group section with a group section,
9705 a linkonce section with a linkonce section, and ignore comdat
9706 section. */
9707 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9708 && strcmp (name, l->sec->name) == 0
9709 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9711 /* The section has already been linked. See if we should
9712 issue a warning. */
9713 switch (flags & SEC_LINK_DUPLICATES)
9715 default:
9716 abort ();
9718 case SEC_LINK_DUPLICATES_DISCARD:
9719 break;
9721 case SEC_LINK_DUPLICATES_ONE_ONLY:
9722 (*_bfd_error_handler)
9723 (_("%B: ignoring duplicate section `%A'"),
9724 abfd, sec);
9725 break;
9727 case SEC_LINK_DUPLICATES_SAME_SIZE:
9728 if (sec->size != l->sec->size)
9729 (*_bfd_error_handler)
9730 (_("%B: duplicate section `%A' has different size"),
9731 abfd, sec);
9732 break;
9734 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
9735 if (sec->size != l->sec->size)
9736 (*_bfd_error_handler)
9737 (_("%B: duplicate section `%A' has different size"),
9738 abfd, sec);
9739 else if (sec->size != 0)
9741 bfd_byte *sec_contents, *l_sec_contents;
9743 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
9744 (*_bfd_error_handler)
9745 (_("%B: warning: could not read contents of section `%A'"),
9746 abfd, sec);
9747 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
9748 &l_sec_contents))
9749 (*_bfd_error_handler)
9750 (_("%B: warning: could not read contents of section `%A'"),
9751 l->sec->owner, l->sec);
9752 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
9753 (*_bfd_error_handler)
9754 (_("%B: warning: duplicate section `%A' has different contents"),
9755 abfd, sec);
9757 if (sec_contents)
9758 free (sec_contents);
9759 if (l_sec_contents)
9760 free (l_sec_contents);
9762 break;
9765 /* Set the output_section field so that lang_add_section
9766 does not create a lang_input_section structure for this
9767 section. Since there might be a symbol in the section
9768 being discarded, we must retain a pointer to the section
9769 which we are really going to use. */
9770 sec->output_section = bfd_abs_section_ptr;
9771 sec->kept_section = l->sec;
9773 if (flags & SEC_GROUP)
9775 asection *first = elf_next_in_group (sec);
9776 asection *s = first;
9778 while (s != NULL)
9780 s->output_section = bfd_abs_section_ptr;
9781 /* Record which group discards it. */
9782 s->kept_section = l->sec;
9783 s = elf_next_in_group (s);
9784 /* These lists are circular. */
9785 if (s == first)
9786 break;
9790 return;
9794 if (group)
9796 /* If this is the member of a single member comdat group and the
9797 group hasn't be discarded, we check if it matches a linkonce
9798 section. We only record the discarded comdat group. Otherwise
9799 the undiscarded group will be discarded incorrectly later since
9800 itself has been recorded. */
9801 for (l = already_linked_list->entry; l != NULL; l = l->next)
9802 if ((l->sec->flags & SEC_GROUP) == 0
9803 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9804 && bfd_elf_match_symbols_in_sections (l->sec,
9805 elf_next_in_group (sec)))
9807 elf_next_in_group (sec)->output_section = bfd_abs_section_ptr;
9808 elf_next_in_group (sec)->kept_section = l->sec;
9809 group->output_section = bfd_abs_section_ptr;
9810 break;
9812 if (l == NULL)
9813 return;
9815 else
9816 /* There is no direct match. But for linkonce section, we should
9817 check if there is a match with comdat group member. We always
9818 record the linkonce section, discarded or not. */
9819 for (l = already_linked_list->entry; l != NULL; l = l->next)
9820 if (l->sec->flags & SEC_GROUP)
9822 asection *first = elf_next_in_group (l->sec);
9824 if (first != NULL
9825 && elf_next_in_group (first) == first
9826 && bfd_elf_match_symbols_in_sections (first, sec))
9828 sec->output_section = bfd_abs_section_ptr;
9829 sec->kept_section = l->sec;
9830 break;
9834 /* This is the first section with this name. Record it. */
9835 bfd_section_already_linked_table_insert (already_linked_list, sec);
9838 static void
9839 bfd_elf_set_symbol (struct elf_link_hash_entry *h, bfd_vma val,
9840 struct bfd_section *s)
9842 h->root.type = bfd_link_hash_defined;
9843 h->root.u.def.section = s ? s : bfd_abs_section_ptr;
9844 h->root.u.def.value = val;
9845 h->def_regular = 1;
9846 h->type = STT_OBJECT;
9847 h->other = STV_HIDDEN | (h->other & ~ ELF_ST_VISIBILITY (-1));
9848 h->forced_local = 1;
9851 /* Set NAME to VAL if the symbol exists and is not defined in a regular
9852 object file. If S is NULL it is an absolute symbol, otherwise it is
9853 relative to that section. */
9855 void
9856 _bfd_elf_provide_symbol (struct bfd_link_info *info, const char *name,
9857 bfd_vma val, struct bfd_section *s)
9859 struct elf_link_hash_entry *h;
9861 bfd_elf_record_link_assignment (info, name, TRUE);
9863 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
9864 if (h != NULL
9865 && !(h->root.type == bfd_link_hash_defined
9866 && h->root.u.def.section != NULL
9867 && h->root.u.def.section != h->root.u.def.section->output_section))
9868 bfd_elf_set_symbol (h, val, s);
9871 /* Set START and END to boundaries of SEC if they exist and are not
9872 defined in regular object files. */
9874 void
9875 _bfd_elf_provide_section_bound_symbols (struct bfd_link_info *info,
9876 asection *sec,
9877 const char *start,
9878 const char *end)
9880 bfd_vma val = 0;
9881 _bfd_elf_provide_symbol (info, start, val, sec);
9882 if (sec != NULL)
9883 val = sec->size;
9884 _bfd_elf_provide_symbol (info, end, val, sec);
9887 /* Convert symbols in excluded output sections to absolute. */
9889 static bfd_boolean
9890 fix_syms (struct bfd_link_hash_entry *h, void *data)
9892 bfd *obfd = (bfd *) data;
9894 if (h->type == bfd_link_hash_warning)
9895 h = h->u.i.link;
9897 if (h->type == bfd_link_hash_defined
9898 || h->type == bfd_link_hash_defweak)
9900 asection *s = h->u.def.section;
9901 if (s != NULL
9902 && s->output_section != NULL
9903 && (s->output_section->flags & SEC_EXCLUDE) != 0
9904 && bfd_section_removed_from_list (obfd, s->output_section))
9906 h->u.def.value += s->output_offset + s->output_section->vma;
9907 h->u.def.section = bfd_abs_section_ptr;
9911 return TRUE;
9914 void
9915 _bfd_elf_fix_excluded_sec_syms (bfd *obfd, struct bfd_link_info *info)
9917 bfd_link_hash_traverse (info->hash, fix_syms, obfd);
9920 bfd_boolean
9921 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
9923 return sym->st_shndx == SHN_COMMON;
9926 unsigned int
9927 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
9929 return SHN_COMMON;
9932 asection *
9933 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
9935 return bfd_com_section_ptr;