PR gas/11507
[binutils.git] / bfd / elflink.c
blobf445912dc98e50968deaed1e99ff78aff0c6f1e3
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
3 2005, 2006, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 MA 02110-1301, USA. */
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "bfdlink.h"
26 #include "libbfd.h"
27 #define ARCH_SIZE 0
28 #include "elf-bfd.h"
29 #include "safe-ctype.h"
30 #include "libiberty.h"
31 #include "objalloc.h"
33 /* This struct is used to pass information to routines called via
34 elf_link_hash_traverse which must return failure. */
36 struct elf_info_failed
38 struct bfd_link_info *info;
39 struct bfd_elf_version_tree *verdefs;
40 bfd_boolean failed;
43 /* This structure is used to pass information to
44 _bfd_elf_link_find_version_dependencies. */
46 struct elf_find_verdep_info
48 /* General link information. */
49 struct bfd_link_info *info;
50 /* The number of dependencies. */
51 unsigned int vers;
52 /* Whether we had a failure. */
53 bfd_boolean failed;
56 static bfd_boolean _bfd_elf_fix_symbol_flags
57 (struct elf_link_hash_entry *, struct elf_info_failed *);
59 /* Define a symbol in a dynamic linkage section. */
61 struct elf_link_hash_entry *
62 _bfd_elf_define_linkage_sym (bfd *abfd,
63 struct bfd_link_info *info,
64 asection *sec,
65 const char *name)
67 struct elf_link_hash_entry *h;
68 struct bfd_link_hash_entry *bh;
69 const struct elf_backend_data *bed;
71 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
72 if (h != NULL)
74 /* Zap symbol defined in an as-needed lib that wasn't linked.
75 This is a symptom of a larger problem: Absolute symbols
76 defined in shared libraries can't be overridden, because we
77 lose the link to the bfd which is via the symbol section. */
78 h->root.type = bfd_link_hash_new;
81 bh = &h->root;
82 if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
83 sec, 0, NULL, FALSE,
84 get_elf_backend_data (abfd)->collect,
85 &bh))
86 return NULL;
87 h = (struct elf_link_hash_entry *) bh;
88 h->def_regular = 1;
89 h->type = STT_OBJECT;
90 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
92 bed = get_elf_backend_data (abfd);
93 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
94 return h;
97 bfd_boolean
98 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
100 flagword flags;
101 asection *s;
102 struct elf_link_hash_entry *h;
103 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
104 struct elf_link_hash_table *htab = elf_hash_table (info);
106 /* This function may be called more than once. */
107 s = bfd_get_section_by_name (abfd, ".got");
108 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
109 return TRUE;
111 flags = bed->dynamic_sec_flags;
113 s = bfd_make_section_with_flags (abfd,
114 (bed->rela_plts_and_copies_p
115 ? ".rela.got" : ".rel.got"),
116 (bed->dynamic_sec_flags
117 | SEC_READONLY));
118 if (s == NULL
119 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
120 return FALSE;
121 htab->srelgot = s;
123 s = bfd_make_section_with_flags (abfd, ".got", flags);
124 if (s == NULL
125 || !bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
126 return FALSE;
127 htab->sgot = s;
129 if (bed->want_got_plt)
131 s = bfd_make_section_with_flags (abfd, ".got.plt", flags);
132 if (s == NULL
133 || !bfd_set_section_alignment (abfd, s,
134 bed->s->log_file_align))
135 return FALSE;
136 htab->sgotplt = s;
139 /* The first bit of the global offset table is the header. */
140 s->size += bed->got_header_size;
142 if (bed->want_got_sym)
144 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
145 (or .got.plt) section. We don't do this in the linker script
146 because we don't want to define the symbol if we are not creating
147 a global offset table. */
148 h = _bfd_elf_define_linkage_sym (abfd, info, s,
149 "_GLOBAL_OFFSET_TABLE_");
150 elf_hash_table (info)->hgot = h;
151 if (h == NULL)
152 return FALSE;
155 return TRUE;
158 /* Create a strtab to hold the dynamic symbol names. */
159 static bfd_boolean
160 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
162 struct elf_link_hash_table *hash_table;
164 hash_table = elf_hash_table (info);
165 if (hash_table->dynobj == NULL)
166 hash_table->dynobj = abfd;
168 if (hash_table->dynstr == NULL)
170 hash_table->dynstr = _bfd_elf_strtab_init ();
171 if (hash_table->dynstr == NULL)
172 return FALSE;
174 return TRUE;
177 /* Create some sections which will be filled in with dynamic linking
178 information. ABFD is an input file which requires dynamic sections
179 to be created. The dynamic sections take up virtual memory space
180 when the final executable is run, so we need to create them before
181 addresses are assigned to the output sections. We work out the
182 actual contents and size of these sections later. */
184 bfd_boolean
185 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
187 flagword flags;
188 asection *s;
189 const struct elf_backend_data *bed;
191 if (! is_elf_hash_table (info->hash))
192 return FALSE;
194 if (elf_hash_table (info)->dynamic_sections_created)
195 return TRUE;
197 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
198 return FALSE;
200 abfd = elf_hash_table (info)->dynobj;
201 bed = get_elf_backend_data (abfd);
203 flags = bed->dynamic_sec_flags;
205 /* A dynamically linked executable has a .interp section, but a
206 shared library does not. */
207 if (info->executable)
209 s = bfd_make_section_with_flags (abfd, ".interp",
210 flags | SEC_READONLY);
211 if (s == NULL)
212 return FALSE;
215 /* Create sections to hold version informations. These are removed
216 if they are not needed. */
217 s = bfd_make_section_with_flags (abfd, ".gnu.version_d",
218 flags | SEC_READONLY);
219 if (s == NULL
220 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
221 return FALSE;
223 s = bfd_make_section_with_flags (abfd, ".gnu.version",
224 flags | SEC_READONLY);
225 if (s == NULL
226 || ! bfd_set_section_alignment (abfd, s, 1))
227 return FALSE;
229 s = bfd_make_section_with_flags (abfd, ".gnu.version_r",
230 flags | SEC_READONLY);
231 if (s == NULL
232 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
233 return FALSE;
235 s = bfd_make_section_with_flags (abfd, ".dynsym",
236 flags | SEC_READONLY);
237 if (s == NULL
238 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
239 return FALSE;
241 s = bfd_make_section_with_flags (abfd, ".dynstr",
242 flags | SEC_READONLY);
243 if (s == NULL)
244 return FALSE;
246 s = bfd_make_section_with_flags (abfd, ".dynamic", flags);
247 if (s == NULL
248 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
249 return FALSE;
251 /* The special symbol _DYNAMIC is always set to the start of the
252 .dynamic section. We could set _DYNAMIC in a linker script, but we
253 only want to define it if we are, in fact, creating a .dynamic
254 section. We don't want to define it if there is no .dynamic
255 section, since on some ELF platforms the start up code examines it
256 to decide how to initialize the process. */
257 if (!_bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC"))
258 return FALSE;
260 if (info->emit_hash)
262 s = bfd_make_section_with_flags (abfd, ".hash", flags | SEC_READONLY);
263 if (s == NULL
264 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
265 return FALSE;
266 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
269 if (info->emit_gnu_hash)
271 s = bfd_make_section_with_flags (abfd, ".gnu.hash",
272 flags | SEC_READONLY);
273 if (s == NULL
274 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
275 return FALSE;
276 /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
277 4 32-bit words followed by variable count of 64-bit words, then
278 variable count of 32-bit words. */
279 if (bed->s->arch_size == 64)
280 elf_section_data (s)->this_hdr.sh_entsize = 0;
281 else
282 elf_section_data (s)->this_hdr.sh_entsize = 4;
285 /* Let the backend create the rest of the sections. This lets the
286 backend set the right flags. The backend will normally create
287 the .got and .plt sections. */
288 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
289 return FALSE;
291 elf_hash_table (info)->dynamic_sections_created = TRUE;
293 return TRUE;
296 /* Create dynamic sections when linking against a dynamic object. */
298 bfd_boolean
299 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
301 flagword flags, pltflags;
302 struct elf_link_hash_entry *h;
303 asection *s;
304 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
305 struct elf_link_hash_table *htab = elf_hash_table (info);
307 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
308 .rel[a].bss sections. */
309 flags = bed->dynamic_sec_flags;
311 pltflags = flags;
312 if (bed->plt_not_loaded)
313 /* We do not clear SEC_ALLOC here because we still want the OS to
314 allocate space for the section; it's just that there's nothing
315 to read in from the object file. */
316 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
317 else
318 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
319 if (bed->plt_readonly)
320 pltflags |= SEC_READONLY;
322 s = bfd_make_section_with_flags (abfd, ".plt", pltflags);
323 if (s == NULL
324 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
325 return FALSE;
326 htab->splt = s;
328 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
329 .plt section. */
330 if (bed->want_plt_sym)
332 h = _bfd_elf_define_linkage_sym (abfd, info, s,
333 "_PROCEDURE_LINKAGE_TABLE_");
334 elf_hash_table (info)->hplt = h;
335 if (h == NULL)
336 return FALSE;
339 s = bfd_make_section_with_flags (abfd,
340 (bed->rela_plts_and_copies_p
341 ? ".rela.plt" : ".rel.plt"),
342 flags | SEC_READONLY);
343 if (s == NULL
344 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
345 return FALSE;
346 htab->srelplt = s;
348 if (! _bfd_elf_create_got_section (abfd, info))
349 return FALSE;
351 if (bed->want_dynbss)
353 /* The .dynbss section is a place to put symbols which are defined
354 by dynamic objects, are referenced by regular objects, and are
355 not functions. We must allocate space for them in the process
356 image and use a R_*_COPY reloc to tell the dynamic linker to
357 initialize them at run time. The linker script puts the .dynbss
358 section into the .bss section of the final image. */
359 s = bfd_make_section_with_flags (abfd, ".dynbss",
360 (SEC_ALLOC
361 | SEC_LINKER_CREATED));
362 if (s == NULL)
363 return FALSE;
365 /* The .rel[a].bss section holds copy relocs. This section is not
366 normally needed. We need to create it here, though, so that the
367 linker will map it to an output section. We can't just create it
368 only if we need it, because we will not know whether we need it
369 until we have seen all the input files, and the first time the
370 main linker code calls BFD after examining all the input files
371 (size_dynamic_sections) the input sections have already been
372 mapped to the output sections. If the section turns out not to
373 be needed, we can discard it later. We will never need this
374 section when generating a shared object, since they do not use
375 copy relocs. */
376 if (! info->shared)
378 s = bfd_make_section_with_flags (abfd,
379 (bed->rela_plts_and_copies_p
380 ? ".rela.bss" : ".rel.bss"),
381 flags | SEC_READONLY);
382 if (s == NULL
383 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
384 return FALSE;
388 return TRUE;
391 /* Record a new dynamic symbol. We record the dynamic symbols as we
392 read the input files, since we need to have a list of all of them
393 before we can determine the final sizes of the output sections.
394 Note that we may actually call this function even though we are not
395 going to output any dynamic symbols; in some cases we know that a
396 symbol should be in the dynamic symbol table, but only if there is
397 one. */
399 bfd_boolean
400 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
401 struct elf_link_hash_entry *h)
403 if (h->dynindx == -1)
405 struct elf_strtab_hash *dynstr;
406 char *p;
407 const char *name;
408 bfd_size_type indx;
410 /* XXX: The ABI draft says the linker must turn hidden and
411 internal symbols into STB_LOCAL symbols when producing the
412 DSO. However, if ld.so honors st_other in the dynamic table,
413 this would not be necessary. */
414 switch (ELF_ST_VISIBILITY (h->other))
416 case STV_INTERNAL:
417 case STV_HIDDEN:
418 if (h->root.type != bfd_link_hash_undefined
419 && h->root.type != bfd_link_hash_undefweak)
421 h->forced_local = 1;
422 if (!elf_hash_table (info)->is_relocatable_executable)
423 return TRUE;
426 default:
427 break;
430 h->dynindx = elf_hash_table (info)->dynsymcount;
431 ++elf_hash_table (info)->dynsymcount;
433 dynstr = elf_hash_table (info)->dynstr;
434 if (dynstr == NULL)
436 /* Create a strtab to hold the dynamic symbol names. */
437 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
438 if (dynstr == NULL)
439 return FALSE;
442 /* We don't put any version information in the dynamic string
443 table. */
444 name = h->root.root.string;
445 p = strchr (name, ELF_VER_CHR);
446 if (p != NULL)
447 /* We know that the p points into writable memory. In fact,
448 there are only a few symbols that have read-only names, being
449 those like _GLOBAL_OFFSET_TABLE_ that are created specially
450 by the backends. Most symbols will have names pointing into
451 an ELF string table read from a file, or to objalloc memory. */
452 *p = 0;
454 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
456 if (p != NULL)
457 *p = ELF_VER_CHR;
459 if (indx == (bfd_size_type) -1)
460 return FALSE;
461 h->dynstr_index = indx;
464 return TRUE;
467 /* Mark a symbol dynamic. */
469 static void
470 bfd_elf_link_mark_dynamic_symbol (struct bfd_link_info *info,
471 struct elf_link_hash_entry *h,
472 Elf_Internal_Sym *sym)
474 struct bfd_elf_dynamic_list *d = info->dynamic_list;
476 /* It may be called more than once on the same H. */
477 if(h->dynamic || info->relocatable)
478 return;
480 if ((info->dynamic_data
481 && (h->type == STT_OBJECT
482 || (sym != NULL
483 && ELF_ST_TYPE (sym->st_info) == STT_OBJECT)))
484 || (d != NULL
485 && h->root.type == bfd_link_hash_new
486 && (*d->match) (&d->head, NULL, h->root.root.string)))
487 h->dynamic = 1;
490 /* Record an assignment to a symbol made by a linker script. We need
491 this in case some dynamic object refers to this symbol. */
493 bfd_boolean
494 bfd_elf_record_link_assignment (bfd *output_bfd,
495 struct bfd_link_info *info,
496 const char *name,
497 bfd_boolean provide,
498 bfd_boolean hidden)
500 struct elf_link_hash_entry *h, *hv;
501 struct elf_link_hash_table *htab;
502 const struct elf_backend_data *bed;
504 if (!is_elf_hash_table (info->hash))
505 return TRUE;
507 htab = elf_hash_table (info);
508 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
509 if (h == NULL)
510 return provide;
512 switch (h->root.type)
514 case bfd_link_hash_defined:
515 case bfd_link_hash_defweak:
516 case bfd_link_hash_common:
517 break;
518 case bfd_link_hash_undefweak:
519 case bfd_link_hash_undefined:
520 /* Since we're defining the symbol, don't let it seem to have not
521 been defined. record_dynamic_symbol and size_dynamic_sections
522 may depend on this. */
523 h->root.type = bfd_link_hash_new;
524 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
525 bfd_link_repair_undef_list (&htab->root);
526 break;
527 case bfd_link_hash_new:
528 bfd_elf_link_mark_dynamic_symbol (info, h, NULL);
529 h->non_elf = 0;
530 break;
531 case bfd_link_hash_indirect:
532 /* We had a versioned symbol in a dynamic library. We make the
533 the versioned symbol point to this one. */
534 bed = get_elf_backend_data (output_bfd);
535 hv = h;
536 while (hv->root.type == bfd_link_hash_indirect
537 || hv->root.type == bfd_link_hash_warning)
538 hv = (struct elf_link_hash_entry *) hv->root.u.i.link;
539 /* We don't need to update h->root.u since linker will set them
540 later. */
541 h->root.type = bfd_link_hash_undefined;
542 hv->root.type = bfd_link_hash_indirect;
543 hv->root.u.i.link = (struct bfd_link_hash_entry *) h;
544 (*bed->elf_backend_copy_indirect_symbol) (info, h, hv);
545 break;
546 case bfd_link_hash_warning:
547 abort ();
548 break;
551 /* If this symbol is being provided by the linker script, and it is
552 currently defined by a dynamic object, but not by a regular
553 object, then mark it as undefined so that the generic linker will
554 force the correct value. */
555 if (provide
556 && h->def_dynamic
557 && !h->def_regular)
558 h->root.type = bfd_link_hash_undefined;
560 /* If this symbol is not being provided by the linker script, and it is
561 currently defined by a dynamic object, but not by a regular object,
562 then clear out any version information because the symbol will not be
563 associated with the dynamic object any more. */
564 if (!provide
565 && h->def_dynamic
566 && !h->def_regular)
567 h->verinfo.verdef = NULL;
569 h->def_regular = 1;
571 if (provide && hidden)
573 bed = get_elf_backend_data (output_bfd);
574 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
575 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
578 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
579 and executables. */
580 if (!info->relocatable
581 && h->dynindx != -1
582 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
583 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
584 h->forced_local = 1;
586 if ((h->def_dynamic
587 || h->ref_dynamic
588 || info->shared
589 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
590 && h->dynindx == -1)
592 if (! bfd_elf_link_record_dynamic_symbol (info, h))
593 return FALSE;
595 /* If this is a weak defined symbol, and we know a corresponding
596 real symbol from the same dynamic object, make sure the real
597 symbol is also made into a dynamic symbol. */
598 if (h->u.weakdef != NULL
599 && h->u.weakdef->dynindx == -1)
601 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
602 return FALSE;
606 return TRUE;
609 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
610 success, and 2 on a failure caused by attempting to record a symbol
611 in a discarded section, eg. a discarded link-once section symbol. */
614 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
615 bfd *input_bfd,
616 long input_indx)
618 bfd_size_type amt;
619 struct elf_link_local_dynamic_entry *entry;
620 struct elf_link_hash_table *eht;
621 struct elf_strtab_hash *dynstr;
622 unsigned long dynstr_index;
623 char *name;
624 Elf_External_Sym_Shndx eshndx;
625 char esym[sizeof (Elf64_External_Sym)];
627 if (! is_elf_hash_table (info->hash))
628 return 0;
630 /* See if the entry exists already. */
631 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
632 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
633 return 1;
635 amt = sizeof (*entry);
636 entry = (struct elf_link_local_dynamic_entry *) bfd_alloc (input_bfd, amt);
637 if (entry == NULL)
638 return 0;
640 /* Go find the symbol, so that we can find it's name. */
641 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
642 1, input_indx, &entry->isym, esym, &eshndx))
644 bfd_release (input_bfd, entry);
645 return 0;
648 if (entry->isym.st_shndx != SHN_UNDEF
649 && entry->isym.st_shndx < SHN_LORESERVE)
651 asection *s;
653 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
654 if (s == NULL || bfd_is_abs_section (s->output_section))
656 /* We can still bfd_release here as nothing has done another
657 bfd_alloc. We can't do this later in this function. */
658 bfd_release (input_bfd, entry);
659 return 2;
663 name = (bfd_elf_string_from_elf_section
664 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
665 entry->isym.st_name));
667 dynstr = elf_hash_table (info)->dynstr;
668 if (dynstr == NULL)
670 /* Create a strtab to hold the dynamic symbol names. */
671 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
672 if (dynstr == NULL)
673 return 0;
676 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
677 if (dynstr_index == (unsigned long) -1)
678 return 0;
679 entry->isym.st_name = dynstr_index;
681 eht = elf_hash_table (info);
683 entry->next = eht->dynlocal;
684 eht->dynlocal = entry;
685 entry->input_bfd = input_bfd;
686 entry->input_indx = input_indx;
687 eht->dynsymcount++;
689 /* Whatever binding the symbol had before, it's now local. */
690 entry->isym.st_info
691 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
693 /* The dynindx will be set at the end of size_dynamic_sections. */
695 return 1;
698 /* Return the dynindex of a local dynamic symbol. */
700 long
701 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
702 bfd *input_bfd,
703 long input_indx)
705 struct elf_link_local_dynamic_entry *e;
707 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
708 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
709 return e->dynindx;
710 return -1;
713 /* This function is used to renumber the dynamic symbols, if some of
714 them are removed because they are marked as local. This is called
715 via elf_link_hash_traverse. */
717 static bfd_boolean
718 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
719 void *data)
721 size_t *count = (size_t *) data;
723 if (h->root.type == bfd_link_hash_warning)
724 h = (struct elf_link_hash_entry *) h->root.u.i.link;
726 if (h->forced_local)
727 return TRUE;
729 if (h->dynindx != -1)
730 h->dynindx = ++(*count);
732 return TRUE;
736 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
737 STB_LOCAL binding. */
739 static bfd_boolean
740 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
741 void *data)
743 size_t *count = (size_t *) data;
745 if (h->root.type == bfd_link_hash_warning)
746 h = (struct elf_link_hash_entry *) h->root.u.i.link;
748 if (!h->forced_local)
749 return TRUE;
751 if (h->dynindx != -1)
752 h->dynindx = ++(*count);
754 return TRUE;
757 /* Return true if the dynamic symbol for a given section should be
758 omitted when creating a shared library. */
759 bfd_boolean
760 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
761 struct bfd_link_info *info,
762 asection *p)
764 struct elf_link_hash_table *htab;
766 switch (elf_section_data (p)->this_hdr.sh_type)
768 case SHT_PROGBITS:
769 case SHT_NOBITS:
770 /* If sh_type is yet undecided, assume it could be
771 SHT_PROGBITS/SHT_NOBITS. */
772 case SHT_NULL:
773 htab = elf_hash_table (info);
774 if (p == htab->tls_sec)
775 return FALSE;
777 if (htab->text_index_section != NULL)
778 return p != htab->text_index_section && p != htab->data_index_section;
780 if (strcmp (p->name, ".got") == 0
781 || strcmp (p->name, ".got.plt") == 0
782 || strcmp (p->name, ".plt") == 0)
784 asection *ip;
786 if (htab->dynobj != NULL
787 && (ip = bfd_get_section_by_name (htab->dynobj, p->name)) != NULL
788 && (ip->flags & SEC_LINKER_CREATED)
789 && ip->output_section == p)
790 return TRUE;
792 return FALSE;
794 /* There shouldn't be section relative relocations
795 against any other section. */
796 default:
797 return TRUE;
801 /* Assign dynsym indices. In a shared library we generate a section
802 symbol for each output section, which come first. Next come symbols
803 which have been forced to local binding. Then all of the back-end
804 allocated local dynamic syms, followed by the rest of the global
805 symbols. */
807 static unsigned long
808 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
809 struct bfd_link_info *info,
810 unsigned long *section_sym_count)
812 unsigned long dynsymcount = 0;
814 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
816 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
817 asection *p;
818 for (p = output_bfd->sections; p ; p = p->next)
819 if ((p->flags & SEC_EXCLUDE) == 0
820 && (p->flags & SEC_ALLOC) != 0
821 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
822 elf_section_data (p)->dynindx = ++dynsymcount;
823 else
824 elf_section_data (p)->dynindx = 0;
826 *section_sym_count = dynsymcount;
828 elf_link_hash_traverse (elf_hash_table (info),
829 elf_link_renumber_local_hash_table_dynsyms,
830 &dynsymcount);
832 if (elf_hash_table (info)->dynlocal)
834 struct elf_link_local_dynamic_entry *p;
835 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
836 p->dynindx = ++dynsymcount;
839 elf_link_hash_traverse (elf_hash_table (info),
840 elf_link_renumber_hash_table_dynsyms,
841 &dynsymcount);
843 /* There is an unused NULL entry at the head of the table which
844 we must account for in our count. Unless there weren't any
845 symbols, which means we'll have no table at all. */
846 if (dynsymcount != 0)
847 ++dynsymcount;
849 elf_hash_table (info)->dynsymcount = dynsymcount;
850 return dynsymcount;
853 /* Merge st_other field. */
855 static void
856 elf_merge_st_other (bfd *abfd, struct elf_link_hash_entry *h,
857 Elf_Internal_Sym *isym, bfd_boolean definition,
858 bfd_boolean dynamic)
860 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
862 /* If st_other has a processor-specific meaning, specific
863 code might be needed here. We never merge the visibility
864 attribute with the one from a dynamic object. */
865 if (bed->elf_backend_merge_symbol_attribute)
866 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
867 dynamic);
869 /* If this symbol has default visibility and the user has requested
870 we not re-export it, then mark it as hidden. */
871 if (definition
872 && !dynamic
873 && (abfd->no_export
874 || (abfd->my_archive && abfd->my_archive->no_export))
875 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
876 isym->st_other = (STV_HIDDEN
877 | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
879 if (!dynamic && ELF_ST_VISIBILITY (isym->st_other) != 0)
881 unsigned char hvis, symvis, other, nvis;
883 /* Only merge the visibility. Leave the remainder of the
884 st_other field to elf_backend_merge_symbol_attribute. */
885 other = h->other & ~ELF_ST_VISIBILITY (-1);
887 /* Combine visibilities, using the most constraining one. */
888 hvis = ELF_ST_VISIBILITY (h->other);
889 symvis = ELF_ST_VISIBILITY (isym->st_other);
890 if (! hvis)
891 nvis = symvis;
892 else if (! symvis)
893 nvis = hvis;
894 else
895 nvis = hvis < symvis ? hvis : symvis;
897 h->other = other | nvis;
901 /* This function is called when we want to define a new symbol. It
902 handles the various cases which arise when we find a definition in
903 a dynamic object, or when there is already a definition in a
904 dynamic object. The new symbol is described by NAME, SYM, PSEC,
905 and PVALUE. We set SYM_HASH to the hash table entry. We set
906 OVERRIDE if the old symbol is overriding a new definition. We set
907 TYPE_CHANGE_OK if it is OK for the type to change. We set
908 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
909 change, we mean that we shouldn't warn if the type or size does
910 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
911 object is overridden by a regular object. */
913 bfd_boolean
914 _bfd_elf_merge_symbol (bfd *abfd,
915 struct bfd_link_info *info,
916 const char *name,
917 Elf_Internal_Sym *sym,
918 asection **psec,
919 bfd_vma *pvalue,
920 unsigned int *pold_alignment,
921 struct elf_link_hash_entry **sym_hash,
922 bfd_boolean *skip,
923 bfd_boolean *override,
924 bfd_boolean *type_change_ok,
925 bfd_boolean *size_change_ok)
927 asection *sec, *oldsec;
928 struct elf_link_hash_entry *h;
929 struct elf_link_hash_entry *flip;
930 int bind;
931 bfd *oldbfd;
932 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
933 bfd_boolean newweak, oldweak, newfunc, oldfunc;
934 const struct elf_backend_data *bed;
936 *skip = FALSE;
937 *override = FALSE;
939 sec = *psec;
940 bind = ELF_ST_BIND (sym->st_info);
942 /* Silently discard TLS symbols from --just-syms. There's no way to
943 combine a static TLS block with a new TLS block for this executable. */
944 if (ELF_ST_TYPE (sym->st_info) == STT_TLS
945 && sec->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
947 *skip = TRUE;
948 return TRUE;
951 if (! bfd_is_und_section (sec))
952 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
953 else
954 h = ((struct elf_link_hash_entry *)
955 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
956 if (h == NULL)
957 return FALSE;
958 *sym_hash = h;
960 bed = get_elf_backend_data (abfd);
962 /* This code is for coping with dynamic objects, and is only useful
963 if we are doing an ELF link. */
964 if (!(*bed->relocs_compatible) (abfd->xvec, info->output_bfd->xvec))
965 return TRUE;
967 /* For merging, we only care about real symbols. */
969 while (h->root.type == bfd_link_hash_indirect
970 || h->root.type == bfd_link_hash_warning)
971 h = (struct elf_link_hash_entry *) h->root.u.i.link;
973 /* We have to check it for every instance since the first few may be
974 refereences and not all compilers emit symbol type for undefined
975 symbols. */
976 bfd_elf_link_mark_dynamic_symbol (info, h, sym);
978 /* If we just created the symbol, mark it as being an ELF symbol.
979 Other than that, there is nothing to do--there is no merge issue
980 with a newly defined symbol--so we just return. */
982 if (h->root.type == bfd_link_hash_new)
984 h->non_elf = 0;
985 return TRUE;
988 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
989 existing symbol. */
991 switch (h->root.type)
993 default:
994 oldbfd = NULL;
995 oldsec = NULL;
996 break;
998 case bfd_link_hash_undefined:
999 case bfd_link_hash_undefweak:
1000 oldbfd = h->root.u.undef.abfd;
1001 oldsec = NULL;
1002 break;
1004 case bfd_link_hash_defined:
1005 case bfd_link_hash_defweak:
1006 oldbfd = h->root.u.def.section->owner;
1007 oldsec = h->root.u.def.section;
1008 break;
1010 case bfd_link_hash_common:
1011 oldbfd = h->root.u.c.p->section->owner;
1012 oldsec = h->root.u.c.p->section;
1013 break;
1016 /* Differentiate strong and weak symbols. */
1017 newweak = bind == STB_WEAK;
1018 oldweak = (h->root.type == bfd_link_hash_defweak
1019 || h->root.type == bfd_link_hash_undefweak);
1021 /* In cases involving weak versioned symbols, we may wind up trying
1022 to merge a symbol with itself. Catch that here, to avoid the
1023 confusion that results if we try to override a symbol with
1024 itself. The additional tests catch cases like
1025 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
1026 dynamic object, which we do want to handle here. */
1027 if (abfd == oldbfd
1028 && (newweak || oldweak)
1029 && ((abfd->flags & DYNAMIC) == 0
1030 || !h->def_regular))
1031 return TRUE;
1033 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
1034 respectively, is from a dynamic object. */
1036 newdyn = (abfd->flags & DYNAMIC) != 0;
1038 olddyn = FALSE;
1039 if (oldbfd != NULL)
1040 olddyn = (oldbfd->flags & DYNAMIC) != 0;
1041 else if (oldsec != NULL)
1043 /* This handles the special SHN_MIPS_{TEXT,DATA} section
1044 indices used by MIPS ELF. */
1045 olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
1048 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
1049 respectively, appear to be a definition rather than reference. */
1051 newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
1053 olddef = (h->root.type != bfd_link_hash_undefined
1054 && h->root.type != bfd_link_hash_undefweak
1055 && h->root.type != bfd_link_hash_common);
1057 /* NEWFUNC and OLDFUNC indicate whether the new or old symbol,
1058 respectively, appear to be a function. */
1060 newfunc = (ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1061 && bed->is_function_type (ELF_ST_TYPE (sym->st_info)));
1063 oldfunc = (h->type != STT_NOTYPE
1064 && bed->is_function_type (h->type));
1066 /* When we try to create a default indirect symbol from the dynamic
1067 definition with the default version, we skip it if its type and
1068 the type of existing regular definition mismatch. We only do it
1069 if the existing regular definition won't be dynamic. */
1070 if (pold_alignment == NULL
1071 && !info->shared
1072 && !info->export_dynamic
1073 && !h->ref_dynamic
1074 && newdyn
1075 && newdef
1076 && !olddyn
1077 && (olddef || h->root.type == bfd_link_hash_common)
1078 && ELF_ST_TYPE (sym->st_info) != h->type
1079 && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1080 && h->type != STT_NOTYPE
1081 && !(newfunc && oldfunc))
1083 *skip = TRUE;
1084 return TRUE;
1087 /* Check TLS symbol. We don't check undefined symbol introduced by
1088 "ld -u". */
1089 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
1090 && ELF_ST_TYPE (sym->st_info) != h->type
1091 && oldbfd != NULL)
1093 bfd *ntbfd, *tbfd;
1094 bfd_boolean ntdef, tdef;
1095 asection *ntsec, *tsec;
1097 if (h->type == STT_TLS)
1099 ntbfd = abfd;
1100 ntsec = sec;
1101 ntdef = newdef;
1102 tbfd = oldbfd;
1103 tsec = oldsec;
1104 tdef = olddef;
1106 else
1108 ntbfd = oldbfd;
1109 ntsec = oldsec;
1110 ntdef = olddef;
1111 tbfd = abfd;
1112 tsec = sec;
1113 tdef = newdef;
1116 if (tdef && ntdef)
1117 (*_bfd_error_handler)
1118 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
1119 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
1120 else if (!tdef && !ntdef)
1121 (*_bfd_error_handler)
1122 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
1123 tbfd, ntbfd, h->root.root.string);
1124 else if (tdef)
1125 (*_bfd_error_handler)
1126 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
1127 tbfd, tsec, ntbfd, h->root.root.string);
1128 else
1129 (*_bfd_error_handler)
1130 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
1131 tbfd, ntbfd, ntsec, h->root.root.string);
1133 bfd_set_error (bfd_error_bad_value);
1134 return FALSE;
1137 /* We need to remember if a symbol has a definition in a dynamic
1138 object or is weak in all dynamic objects. Internal and hidden
1139 visibility will make it unavailable to dynamic objects. */
1140 if (newdyn && !h->dynamic_def)
1142 if (!bfd_is_und_section (sec))
1143 h->dynamic_def = 1;
1144 else
1146 /* Check if this symbol is weak in all dynamic objects. If it
1147 is the first time we see it in a dynamic object, we mark
1148 if it is weak. Otherwise, we clear it. */
1149 if (!h->ref_dynamic)
1151 if (bind == STB_WEAK)
1152 h->dynamic_weak = 1;
1154 else if (bind != STB_WEAK)
1155 h->dynamic_weak = 0;
1159 /* If the old symbol has non-default visibility, we ignore the new
1160 definition from a dynamic object. */
1161 if (newdyn
1162 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1163 && !bfd_is_und_section (sec))
1165 *skip = TRUE;
1166 /* Make sure this symbol is dynamic. */
1167 h->ref_dynamic = 1;
1168 /* A protected symbol has external availability. Make sure it is
1169 recorded as dynamic.
1171 FIXME: Should we check type and size for protected symbol? */
1172 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1173 return bfd_elf_link_record_dynamic_symbol (info, h);
1174 else
1175 return TRUE;
1177 else if (!newdyn
1178 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1179 && h->def_dynamic)
1181 /* If the new symbol with non-default visibility comes from a
1182 relocatable file and the old definition comes from a dynamic
1183 object, we remove the old definition. */
1184 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1186 /* Handle the case where the old dynamic definition is
1187 default versioned. We need to copy the symbol info from
1188 the symbol with default version to the normal one if it
1189 was referenced before. */
1190 if (h->ref_regular)
1192 struct elf_link_hash_entry *vh = *sym_hash;
1194 vh->root.type = h->root.type;
1195 h->root.type = bfd_link_hash_indirect;
1196 (*bed->elf_backend_copy_indirect_symbol) (info, vh, h);
1197 /* Protected symbols will override the dynamic definition
1198 with default version. */
1199 if (ELF_ST_VISIBILITY (sym->st_other) == STV_PROTECTED)
1201 h->root.u.i.link = (struct bfd_link_hash_entry *) vh;
1202 vh->dynamic_def = 1;
1203 vh->ref_dynamic = 1;
1205 else
1207 h->root.type = vh->root.type;
1208 vh->ref_dynamic = 0;
1209 /* We have to hide it here since it was made dynamic
1210 global with extra bits when the symbol info was
1211 copied from the old dynamic definition. */
1212 (*bed->elf_backend_hide_symbol) (info, vh, TRUE);
1214 h = vh;
1216 else
1217 h = *sym_hash;
1220 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1221 && bfd_is_und_section (sec))
1223 /* If the new symbol is undefined and the old symbol was
1224 also undefined before, we need to make sure
1225 _bfd_generic_link_add_one_symbol doesn't mess
1226 up the linker hash table undefs list. Since the old
1227 definition came from a dynamic object, it is still on the
1228 undefs list. */
1229 h->root.type = bfd_link_hash_undefined;
1230 h->root.u.undef.abfd = abfd;
1232 else
1234 h->root.type = bfd_link_hash_new;
1235 h->root.u.undef.abfd = NULL;
1238 if (h->def_dynamic)
1240 h->def_dynamic = 0;
1241 h->ref_dynamic = 1;
1242 h->dynamic_def = 1;
1244 /* FIXME: Should we check type and size for protected symbol? */
1245 h->size = 0;
1246 h->type = 0;
1247 return TRUE;
1250 if (bind == STB_GNU_UNIQUE)
1251 h->unique_global = 1;
1253 /* If a new weak symbol definition comes from a regular file and the
1254 old symbol comes from a dynamic library, we treat the new one as
1255 strong. Similarly, an old weak symbol definition from a regular
1256 file is treated as strong when the new symbol comes from a dynamic
1257 library. Further, an old weak symbol from a dynamic library is
1258 treated as strong if the new symbol is from a dynamic library.
1259 This reflects the way glibc's ld.so works.
1261 Do this before setting *type_change_ok or *size_change_ok so that
1262 we warn properly when dynamic library symbols are overridden. */
1264 if (newdef && !newdyn && olddyn)
1265 newweak = FALSE;
1266 if (olddef && newdyn)
1267 oldweak = FALSE;
1269 /* Allow changes between different types of function symbol. */
1270 if (newfunc && oldfunc)
1271 *type_change_ok = TRUE;
1273 /* It's OK to change the type if either the existing symbol or the
1274 new symbol is weak. A type change is also OK if the old symbol
1275 is undefined and the new symbol is defined. */
1277 if (oldweak
1278 || newweak
1279 || (newdef
1280 && h->root.type == bfd_link_hash_undefined))
1281 *type_change_ok = TRUE;
1283 /* It's OK to change the size if either the existing symbol or the
1284 new symbol is weak, or if the old symbol is undefined. */
1286 if (*type_change_ok
1287 || h->root.type == bfd_link_hash_undefined)
1288 *size_change_ok = TRUE;
1290 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1291 symbol, respectively, appears to be a common symbol in a dynamic
1292 object. If a symbol appears in an uninitialized section, and is
1293 not weak, and is not a function, then it may be a common symbol
1294 which was resolved when the dynamic object was created. We want
1295 to treat such symbols specially, because they raise special
1296 considerations when setting the symbol size: if the symbol
1297 appears as a common symbol in a regular object, and the size in
1298 the regular object is larger, we must make sure that we use the
1299 larger size. This problematic case can always be avoided in C,
1300 but it must be handled correctly when using Fortran shared
1301 libraries.
1303 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1304 likewise for OLDDYNCOMMON and OLDDEF.
1306 Note that this test is just a heuristic, and that it is quite
1307 possible to have an uninitialized symbol in a shared object which
1308 is really a definition, rather than a common symbol. This could
1309 lead to some minor confusion when the symbol really is a common
1310 symbol in some regular object. However, I think it will be
1311 harmless. */
1313 if (newdyn
1314 && newdef
1315 && !newweak
1316 && (sec->flags & SEC_ALLOC) != 0
1317 && (sec->flags & SEC_LOAD) == 0
1318 && sym->st_size > 0
1319 && !newfunc)
1320 newdyncommon = TRUE;
1321 else
1322 newdyncommon = FALSE;
1324 if (olddyn
1325 && olddef
1326 && h->root.type == bfd_link_hash_defined
1327 && h->def_dynamic
1328 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1329 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1330 && h->size > 0
1331 && !oldfunc)
1332 olddyncommon = TRUE;
1333 else
1334 olddyncommon = FALSE;
1336 /* We now know everything about the old and new symbols. We ask the
1337 backend to check if we can merge them. */
1338 if (bed->merge_symbol
1339 && !bed->merge_symbol (info, sym_hash, h, sym, psec, pvalue,
1340 pold_alignment, skip, override,
1341 type_change_ok, size_change_ok,
1342 &newdyn, &newdef, &newdyncommon, &newweak,
1343 abfd, &sec,
1344 &olddyn, &olddef, &olddyncommon, &oldweak,
1345 oldbfd, &oldsec))
1346 return FALSE;
1348 /* If both the old and the new symbols look like common symbols in a
1349 dynamic object, set the size of the symbol to the larger of the
1350 two. */
1352 if (olddyncommon
1353 && newdyncommon
1354 && sym->st_size != h->size)
1356 /* Since we think we have two common symbols, issue a multiple
1357 common warning if desired. Note that we only warn if the
1358 size is different. If the size is the same, we simply let
1359 the old symbol override the new one as normally happens with
1360 symbols defined in dynamic objects. */
1362 if (! ((*info->callbacks->multiple_common)
1363 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1364 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1365 return FALSE;
1367 if (sym->st_size > h->size)
1368 h->size = sym->st_size;
1370 *size_change_ok = TRUE;
1373 /* If we are looking at a dynamic object, and we have found a
1374 definition, we need to see if the symbol was already defined by
1375 some other object. If so, we want to use the existing
1376 definition, and we do not want to report a multiple symbol
1377 definition error; we do this by clobbering *PSEC to be
1378 bfd_und_section_ptr.
1380 We treat a common symbol as a definition if the symbol in the
1381 shared library is a function, since common symbols always
1382 represent variables; this can cause confusion in principle, but
1383 any such confusion would seem to indicate an erroneous program or
1384 shared library. We also permit a common symbol in a regular
1385 object to override a weak symbol in a shared object. */
1387 if (newdyn
1388 && newdef
1389 && (olddef
1390 || (h->root.type == bfd_link_hash_common
1391 && (newweak || newfunc))))
1393 *override = TRUE;
1394 newdef = FALSE;
1395 newdyncommon = FALSE;
1397 *psec = sec = bfd_und_section_ptr;
1398 *size_change_ok = TRUE;
1400 /* If we get here when the old symbol is a common symbol, then
1401 we are explicitly letting it override a weak symbol or
1402 function in a dynamic object, and we don't want to warn about
1403 a type change. If the old symbol is a defined symbol, a type
1404 change warning may still be appropriate. */
1406 if (h->root.type == bfd_link_hash_common)
1407 *type_change_ok = TRUE;
1410 /* Handle the special case of an old common symbol merging with a
1411 new symbol which looks like a common symbol in a shared object.
1412 We change *PSEC and *PVALUE to make the new symbol look like a
1413 common symbol, and let _bfd_generic_link_add_one_symbol do the
1414 right thing. */
1416 if (newdyncommon
1417 && h->root.type == bfd_link_hash_common)
1419 *override = TRUE;
1420 newdef = FALSE;
1421 newdyncommon = FALSE;
1422 *pvalue = sym->st_size;
1423 *psec = sec = bed->common_section (oldsec);
1424 *size_change_ok = TRUE;
1427 /* Skip weak definitions of symbols that are already defined. */
1428 if (newdef && olddef && newweak)
1430 *skip = TRUE;
1432 /* Merge st_other. If the symbol already has a dynamic index,
1433 but visibility says it should not be visible, turn it into a
1434 local symbol. */
1435 elf_merge_st_other (abfd, h, sym, newdef, newdyn);
1436 if (h->dynindx != -1)
1437 switch (ELF_ST_VISIBILITY (h->other))
1439 case STV_INTERNAL:
1440 case STV_HIDDEN:
1441 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1442 break;
1446 /* If the old symbol is from a dynamic object, and the new symbol is
1447 a definition which is not from a dynamic object, then the new
1448 symbol overrides the old symbol. Symbols from regular files
1449 always take precedence over symbols from dynamic objects, even if
1450 they are defined after the dynamic object in the link.
1452 As above, we again permit a common symbol in a regular object to
1453 override a definition in a shared object if the shared object
1454 symbol is a function or is weak. */
1456 flip = NULL;
1457 if (!newdyn
1458 && (newdef
1459 || (bfd_is_com_section (sec)
1460 && (oldweak || oldfunc)))
1461 && olddyn
1462 && olddef
1463 && h->def_dynamic)
1465 /* Change the hash table entry to undefined, and let
1466 _bfd_generic_link_add_one_symbol do the right thing with the
1467 new definition. */
1469 h->root.type = bfd_link_hash_undefined;
1470 h->root.u.undef.abfd = h->root.u.def.section->owner;
1471 *size_change_ok = TRUE;
1473 olddef = FALSE;
1474 olddyncommon = FALSE;
1476 /* We again permit a type change when a common symbol may be
1477 overriding a function. */
1479 if (bfd_is_com_section (sec))
1481 if (oldfunc)
1483 /* If a common symbol overrides a function, make sure
1484 that it isn't defined dynamically nor has type
1485 function. */
1486 h->def_dynamic = 0;
1487 h->type = STT_NOTYPE;
1489 *type_change_ok = TRUE;
1492 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1493 flip = *sym_hash;
1494 else
1495 /* This union may have been set to be non-NULL when this symbol
1496 was seen in a dynamic object. We must force the union to be
1497 NULL, so that it is correct for a regular symbol. */
1498 h->verinfo.vertree = NULL;
1501 /* Handle the special case of a new common symbol merging with an
1502 old symbol that looks like it might be a common symbol defined in
1503 a shared object. Note that we have already handled the case in
1504 which a new common symbol should simply override the definition
1505 in the shared library. */
1507 if (! newdyn
1508 && bfd_is_com_section (sec)
1509 && olddyncommon)
1511 /* It would be best if we could set the hash table entry to a
1512 common symbol, but we don't know what to use for the section
1513 or the alignment. */
1514 if (! ((*info->callbacks->multiple_common)
1515 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1516 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1517 return FALSE;
1519 /* If the presumed common symbol in the dynamic object is
1520 larger, pretend that the new symbol has its size. */
1522 if (h->size > *pvalue)
1523 *pvalue = h->size;
1525 /* We need to remember the alignment required by the symbol
1526 in the dynamic object. */
1527 BFD_ASSERT (pold_alignment);
1528 *pold_alignment = h->root.u.def.section->alignment_power;
1530 olddef = FALSE;
1531 olddyncommon = FALSE;
1533 h->root.type = bfd_link_hash_undefined;
1534 h->root.u.undef.abfd = h->root.u.def.section->owner;
1536 *size_change_ok = TRUE;
1537 *type_change_ok = TRUE;
1539 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1540 flip = *sym_hash;
1541 else
1542 h->verinfo.vertree = NULL;
1545 if (flip != NULL)
1547 /* Handle the case where we had a versioned symbol in a dynamic
1548 library and now find a definition in a normal object. In this
1549 case, we make the versioned symbol point to the normal one. */
1550 flip->root.type = h->root.type;
1551 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1552 h->root.type = bfd_link_hash_indirect;
1553 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1554 (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1555 if (h->def_dynamic)
1557 h->def_dynamic = 0;
1558 flip->ref_dynamic = 1;
1562 return TRUE;
1565 /* This function is called to create an indirect symbol from the
1566 default for the symbol with the default version if needed. The
1567 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1568 set DYNSYM if the new indirect symbol is dynamic. */
1570 static bfd_boolean
1571 _bfd_elf_add_default_symbol (bfd *abfd,
1572 struct bfd_link_info *info,
1573 struct elf_link_hash_entry *h,
1574 const char *name,
1575 Elf_Internal_Sym *sym,
1576 asection **psec,
1577 bfd_vma *value,
1578 bfd_boolean *dynsym,
1579 bfd_boolean override)
1581 bfd_boolean type_change_ok;
1582 bfd_boolean size_change_ok;
1583 bfd_boolean skip;
1584 char *shortname;
1585 struct elf_link_hash_entry *hi;
1586 struct bfd_link_hash_entry *bh;
1587 const struct elf_backend_data *bed;
1588 bfd_boolean collect;
1589 bfd_boolean dynamic;
1590 char *p;
1591 size_t len, shortlen;
1592 asection *sec;
1594 /* If this symbol has a version, and it is the default version, we
1595 create an indirect symbol from the default name to the fully
1596 decorated name. This will cause external references which do not
1597 specify a version to be bound to this version of the symbol. */
1598 p = strchr (name, ELF_VER_CHR);
1599 if (p == NULL || p[1] != ELF_VER_CHR)
1600 return TRUE;
1602 if (override)
1604 /* We are overridden by an old definition. We need to check if we
1605 need to create the indirect symbol from the default name. */
1606 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1607 FALSE, FALSE);
1608 BFD_ASSERT (hi != NULL);
1609 if (hi == h)
1610 return TRUE;
1611 while (hi->root.type == bfd_link_hash_indirect
1612 || hi->root.type == bfd_link_hash_warning)
1614 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1615 if (hi == h)
1616 return TRUE;
1620 bed = get_elf_backend_data (abfd);
1621 collect = bed->collect;
1622 dynamic = (abfd->flags & DYNAMIC) != 0;
1624 shortlen = p - name;
1625 shortname = (char *) bfd_hash_allocate (&info->hash->table, shortlen + 1);
1626 if (shortname == NULL)
1627 return FALSE;
1628 memcpy (shortname, name, shortlen);
1629 shortname[shortlen] = '\0';
1631 /* We are going to create a new symbol. Merge it with any existing
1632 symbol with this name. For the purposes of the merge, act as
1633 though we were defining the symbol we just defined, although we
1634 actually going to define an indirect symbol. */
1635 type_change_ok = FALSE;
1636 size_change_ok = FALSE;
1637 sec = *psec;
1638 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1639 NULL, &hi, &skip, &override,
1640 &type_change_ok, &size_change_ok))
1641 return FALSE;
1643 if (skip)
1644 goto nondefault;
1646 if (! override)
1648 bh = &hi->root;
1649 if (! (_bfd_generic_link_add_one_symbol
1650 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1651 0, name, FALSE, collect, &bh)))
1652 return FALSE;
1653 hi = (struct elf_link_hash_entry *) bh;
1655 else
1657 /* In this case the symbol named SHORTNAME is overriding the
1658 indirect symbol we want to add. We were planning on making
1659 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1660 is the name without a version. NAME is the fully versioned
1661 name, and it is the default version.
1663 Overriding means that we already saw a definition for the
1664 symbol SHORTNAME in a regular object, and it is overriding
1665 the symbol defined in the dynamic object.
1667 When this happens, we actually want to change NAME, the
1668 symbol we just added, to refer to SHORTNAME. This will cause
1669 references to NAME in the shared object to become references
1670 to SHORTNAME in the regular object. This is what we expect
1671 when we override a function in a shared object: that the
1672 references in the shared object will be mapped to the
1673 definition in the regular object. */
1675 while (hi->root.type == bfd_link_hash_indirect
1676 || hi->root.type == bfd_link_hash_warning)
1677 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1679 h->root.type = bfd_link_hash_indirect;
1680 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1681 if (h->def_dynamic)
1683 h->def_dynamic = 0;
1684 hi->ref_dynamic = 1;
1685 if (hi->ref_regular
1686 || hi->def_regular)
1688 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1689 return FALSE;
1693 /* Now set HI to H, so that the following code will set the
1694 other fields correctly. */
1695 hi = h;
1698 /* Check if HI is a warning symbol. */
1699 if (hi->root.type == bfd_link_hash_warning)
1700 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1702 /* If there is a duplicate definition somewhere, then HI may not
1703 point to an indirect symbol. We will have reported an error to
1704 the user in that case. */
1706 if (hi->root.type == bfd_link_hash_indirect)
1708 struct elf_link_hash_entry *ht;
1710 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1711 (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
1713 /* See if the new flags lead us to realize that the symbol must
1714 be dynamic. */
1715 if (! *dynsym)
1717 if (! dynamic)
1719 if (! info->executable
1720 || hi->ref_dynamic)
1721 *dynsym = TRUE;
1723 else
1725 if (hi->ref_regular)
1726 *dynsym = TRUE;
1731 /* We also need to define an indirection from the nondefault version
1732 of the symbol. */
1734 nondefault:
1735 len = strlen (name);
1736 shortname = (char *) bfd_hash_allocate (&info->hash->table, len);
1737 if (shortname == NULL)
1738 return FALSE;
1739 memcpy (shortname, name, shortlen);
1740 memcpy (shortname + shortlen, p + 1, len - shortlen);
1742 /* Once again, merge with any existing symbol. */
1743 type_change_ok = FALSE;
1744 size_change_ok = FALSE;
1745 sec = *psec;
1746 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1747 NULL, &hi, &skip, &override,
1748 &type_change_ok, &size_change_ok))
1749 return FALSE;
1751 if (skip)
1752 return TRUE;
1754 if (override)
1756 /* Here SHORTNAME is a versioned name, so we don't expect to see
1757 the type of override we do in the case above unless it is
1758 overridden by a versioned definition. */
1759 if (hi->root.type != bfd_link_hash_defined
1760 && hi->root.type != bfd_link_hash_defweak)
1761 (*_bfd_error_handler)
1762 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1763 abfd, shortname);
1765 else
1767 bh = &hi->root;
1768 if (! (_bfd_generic_link_add_one_symbol
1769 (info, abfd, shortname, BSF_INDIRECT,
1770 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1771 return FALSE;
1772 hi = (struct elf_link_hash_entry *) bh;
1774 /* If there is a duplicate definition somewhere, then HI may not
1775 point to an indirect symbol. We will have reported an error
1776 to the user in that case. */
1778 if (hi->root.type == bfd_link_hash_indirect)
1780 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
1782 /* See if the new flags lead us to realize that the symbol
1783 must be dynamic. */
1784 if (! *dynsym)
1786 if (! dynamic)
1788 if (! info->executable
1789 || hi->ref_dynamic)
1790 *dynsym = TRUE;
1792 else
1794 if (hi->ref_regular)
1795 *dynsym = TRUE;
1801 return TRUE;
1804 /* This routine is used to export all defined symbols into the dynamic
1805 symbol table. It is called via elf_link_hash_traverse. */
1807 static bfd_boolean
1808 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1810 struct elf_info_failed *eif = (struct elf_info_failed *) data;
1812 /* Ignore this if we won't export it. */
1813 if (!eif->info->export_dynamic && !h->dynamic)
1814 return TRUE;
1816 /* Ignore indirect symbols. These are added by the versioning code. */
1817 if (h->root.type == bfd_link_hash_indirect)
1818 return TRUE;
1820 if (h->root.type == bfd_link_hash_warning)
1821 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1823 if (h->dynindx == -1
1824 && (h->def_regular
1825 || h->ref_regular))
1827 bfd_boolean hide;
1829 if (eif->verdefs == NULL
1830 || (bfd_find_version_for_sym (eif->verdefs, h->root.root.string, &hide)
1831 && !hide))
1833 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1835 eif->failed = TRUE;
1836 return FALSE;
1841 return TRUE;
1844 /* Look through the symbols which are defined in other shared
1845 libraries and referenced here. Update the list of version
1846 dependencies. This will be put into the .gnu.version_r section.
1847 This function is called via elf_link_hash_traverse. */
1849 static bfd_boolean
1850 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1851 void *data)
1853 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
1854 Elf_Internal_Verneed *t;
1855 Elf_Internal_Vernaux *a;
1856 bfd_size_type amt;
1858 if (h->root.type == bfd_link_hash_warning)
1859 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1861 /* We only care about symbols defined in shared objects with version
1862 information. */
1863 if (!h->def_dynamic
1864 || h->def_regular
1865 || h->dynindx == -1
1866 || h->verinfo.verdef == NULL)
1867 return TRUE;
1869 /* See if we already know about this version. */
1870 for (t = elf_tdata (rinfo->info->output_bfd)->verref;
1871 t != NULL;
1872 t = t->vn_nextref)
1874 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1875 continue;
1877 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1878 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1879 return TRUE;
1881 break;
1884 /* This is a new version. Add it to tree we are building. */
1886 if (t == NULL)
1888 amt = sizeof *t;
1889 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->info->output_bfd, amt);
1890 if (t == NULL)
1892 rinfo->failed = TRUE;
1893 return FALSE;
1896 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1897 t->vn_nextref = elf_tdata (rinfo->info->output_bfd)->verref;
1898 elf_tdata (rinfo->info->output_bfd)->verref = t;
1901 amt = sizeof *a;
1902 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->info->output_bfd, amt);
1903 if (a == NULL)
1905 rinfo->failed = TRUE;
1906 return FALSE;
1909 /* Note that we are copying a string pointer here, and testing it
1910 above. If bfd_elf_string_from_elf_section is ever changed to
1911 discard the string data when low in memory, this will have to be
1912 fixed. */
1913 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1915 a->vna_flags = h->verinfo.verdef->vd_flags;
1916 a->vna_nextptr = t->vn_auxptr;
1918 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1919 ++rinfo->vers;
1921 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1923 t->vn_auxptr = a;
1925 return TRUE;
1928 /* Figure out appropriate versions for all the symbols. We may not
1929 have the version number script until we have read all of the input
1930 files, so until that point we don't know which symbols should be
1931 local. This function is called via elf_link_hash_traverse. */
1933 static bfd_boolean
1934 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1936 struct elf_info_failed *sinfo;
1937 struct bfd_link_info *info;
1938 const struct elf_backend_data *bed;
1939 struct elf_info_failed eif;
1940 char *p;
1941 bfd_size_type amt;
1943 sinfo = (struct elf_info_failed *) data;
1944 info = sinfo->info;
1946 if (h->root.type == bfd_link_hash_warning)
1947 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1949 /* Fix the symbol flags. */
1950 eif.failed = FALSE;
1951 eif.info = info;
1952 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1954 if (eif.failed)
1955 sinfo->failed = TRUE;
1956 return FALSE;
1959 /* We only need version numbers for symbols defined in regular
1960 objects. */
1961 if (!h->def_regular)
1962 return TRUE;
1964 bed = get_elf_backend_data (info->output_bfd);
1965 p = strchr (h->root.root.string, ELF_VER_CHR);
1966 if (p != NULL && h->verinfo.vertree == NULL)
1968 struct bfd_elf_version_tree *t;
1969 bfd_boolean hidden;
1971 hidden = TRUE;
1973 /* There are two consecutive ELF_VER_CHR characters if this is
1974 not a hidden symbol. */
1975 ++p;
1976 if (*p == ELF_VER_CHR)
1978 hidden = FALSE;
1979 ++p;
1982 /* If there is no version string, we can just return out. */
1983 if (*p == '\0')
1985 if (hidden)
1986 h->hidden = 1;
1987 return TRUE;
1990 /* Look for the version. If we find it, it is no longer weak. */
1991 for (t = sinfo->verdefs; t != NULL; t = t->next)
1993 if (strcmp (t->name, p) == 0)
1995 size_t len;
1996 char *alc;
1997 struct bfd_elf_version_expr *d;
1999 len = p - h->root.root.string;
2000 alc = (char *) bfd_malloc (len);
2001 if (alc == NULL)
2003 sinfo->failed = TRUE;
2004 return FALSE;
2006 memcpy (alc, h->root.root.string, len - 1);
2007 alc[len - 1] = '\0';
2008 if (alc[len - 2] == ELF_VER_CHR)
2009 alc[len - 2] = '\0';
2011 h->verinfo.vertree = t;
2012 t->used = TRUE;
2013 d = NULL;
2015 if (t->globals.list != NULL)
2016 d = (*t->match) (&t->globals, NULL, alc);
2018 /* See if there is anything to force this symbol to
2019 local scope. */
2020 if (d == NULL && t->locals.list != NULL)
2022 d = (*t->match) (&t->locals, NULL, alc);
2023 if (d != NULL
2024 && h->dynindx != -1
2025 && ! info->export_dynamic)
2026 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
2029 free (alc);
2030 break;
2034 /* If we are building an application, we need to create a
2035 version node for this version. */
2036 if (t == NULL && info->executable)
2038 struct bfd_elf_version_tree **pp;
2039 int version_index;
2041 /* If we aren't going to export this symbol, we don't need
2042 to worry about it. */
2043 if (h->dynindx == -1)
2044 return TRUE;
2046 amt = sizeof *t;
2047 t = (struct bfd_elf_version_tree *) bfd_zalloc (info->output_bfd, amt);
2048 if (t == NULL)
2050 sinfo->failed = TRUE;
2051 return FALSE;
2054 t->name = p;
2055 t->name_indx = (unsigned int) -1;
2056 t->used = TRUE;
2058 version_index = 1;
2059 /* Don't count anonymous version tag. */
2060 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
2061 version_index = 0;
2062 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
2063 ++version_index;
2064 t->vernum = version_index;
2066 *pp = t;
2068 h->verinfo.vertree = t;
2070 else if (t == NULL)
2072 /* We could not find the version for a symbol when
2073 generating a shared archive. Return an error. */
2074 (*_bfd_error_handler)
2075 (_("%B: version node not found for symbol %s"),
2076 info->output_bfd, h->root.root.string);
2077 bfd_set_error (bfd_error_bad_value);
2078 sinfo->failed = TRUE;
2079 return FALSE;
2082 if (hidden)
2083 h->hidden = 1;
2086 /* If we don't have a version for this symbol, see if we can find
2087 something. */
2088 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
2090 bfd_boolean hide;
2092 h->verinfo.vertree = bfd_find_version_for_sym (sinfo->verdefs,
2093 h->root.root.string, &hide);
2094 if (h->verinfo.vertree != NULL && hide)
2095 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
2098 return TRUE;
2101 /* Read and swap the relocs from the section indicated by SHDR. This
2102 may be either a REL or a RELA section. The relocations are
2103 translated into RELA relocations and stored in INTERNAL_RELOCS,
2104 which should have already been allocated to contain enough space.
2105 The EXTERNAL_RELOCS are a buffer where the external form of the
2106 relocations should be stored.
2108 Returns FALSE if something goes wrong. */
2110 static bfd_boolean
2111 elf_link_read_relocs_from_section (bfd *abfd,
2112 asection *sec,
2113 Elf_Internal_Shdr *shdr,
2114 void *external_relocs,
2115 Elf_Internal_Rela *internal_relocs)
2117 const struct elf_backend_data *bed;
2118 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
2119 const bfd_byte *erela;
2120 const bfd_byte *erelaend;
2121 Elf_Internal_Rela *irela;
2122 Elf_Internal_Shdr *symtab_hdr;
2123 size_t nsyms;
2125 /* Position ourselves at the start of the section. */
2126 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2127 return FALSE;
2129 /* Read the relocations. */
2130 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
2131 return FALSE;
2133 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2134 nsyms = NUM_SHDR_ENTRIES (symtab_hdr);
2136 bed = get_elf_backend_data (abfd);
2138 /* Convert the external relocations to the internal format. */
2139 if (shdr->sh_entsize == bed->s->sizeof_rel)
2140 swap_in = bed->s->swap_reloc_in;
2141 else if (shdr->sh_entsize == bed->s->sizeof_rela)
2142 swap_in = bed->s->swap_reloca_in;
2143 else
2145 bfd_set_error (bfd_error_wrong_format);
2146 return FALSE;
2149 erela = (const bfd_byte *) external_relocs;
2150 erelaend = erela + shdr->sh_size;
2151 irela = internal_relocs;
2152 while (erela < erelaend)
2154 bfd_vma r_symndx;
2156 (*swap_in) (abfd, erela, irela);
2157 r_symndx = ELF32_R_SYM (irela->r_info);
2158 if (bed->s->arch_size == 64)
2159 r_symndx >>= 24;
2160 if (nsyms > 0)
2162 if ((size_t) r_symndx >= nsyms)
2164 (*_bfd_error_handler)
2165 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
2166 " for offset 0x%lx in section `%A'"),
2167 abfd, sec,
2168 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
2169 bfd_set_error (bfd_error_bad_value);
2170 return FALSE;
2173 else if (r_symndx != 0)
2175 (*_bfd_error_handler)
2176 (_("%B: non-zero symbol index (0x%lx) for offset 0x%lx in section `%A'"
2177 " when the object file has no symbol table"),
2178 abfd, sec,
2179 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
2180 bfd_set_error (bfd_error_bad_value);
2181 return FALSE;
2183 irela += bed->s->int_rels_per_ext_rel;
2184 erela += shdr->sh_entsize;
2187 return TRUE;
2190 /* Read and swap the relocs for a section O. They may have been
2191 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2192 not NULL, they are used as buffers to read into. They are known to
2193 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2194 the return value is allocated using either malloc or bfd_alloc,
2195 according to the KEEP_MEMORY argument. If O has two relocation
2196 sections (both REL and RELA relocations), then the REL_HDR
2197 relocations will appear first in INTERNAL_RELOCS, followed by the
2198 REL_HDR2 relocations. */
2200 Elf_Internal_Rela *
2201 _bfd_elf_link_read_relocs (bfd *abfd,
2202 asection *o,
2203 void *external_relocs,
2204 Elf_Internal_Rela *internal_relocs,
2205 bfd_boolean keep_memory)
2207 Elf_Internal_Shdr *rel_hdr;
2208 void *alloc1 = NULL;
2209 Elf_Internal_Rela *alloc2 = NULL;
2210 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2212 if (elf_section_data (o)->relocs != NULL)
2213 return elf_section_data (o)->relocs;
2215 if (o->reloc_count == 0)
2216 return NULL;
2218 rel_hdr = &elf_section_data (o)->rel_hdr;
2220 if (internal_relocs == NULL)
2222 bfd_size_type size;
2224 size = o->reloc_count;
2225 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2226 if (keep_memory)
2227 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2228 else
2229 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2230 if (internal_relocs == NULL)
2231 goto error_return;
2234 if (external_relocs == NULL)
2236 bfd_size_type size = rel_hdr->sh_size;
2238 if (elf_section_data (o)->rel_hdr2)
2239 size += elf_section_data (o)->rel_hdr2->sh_size;
2240 alloc1 = bfd_malloc (size);
2241 if (alloc1 == NULL)
2242 goto error_return;
2243 external_relocs = alloc1;
2246 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2247 external_relocs,
2248 internal_relocs))
2249 goto error_return;
2250 if (elf_section_data (o)->rel_hdr2
2251 && (!elf_link_read_relocs_from_section
2252 (abfd, o,
2253 elf_section_data (o)->rel_hdr2,
2254 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2255 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2256 * bed->s->int_rels_per_ext_rel))))
2257 goto error_return;
2259 /* Cache the results for next time, if we can. */
2260 if (keep_memory)
2261 elf_section_data (o)->relocs = internal_relocs;
2263 if (alloc1 != NULL)
2264 free (alloc1);
2266 /* Don't free alloc2, since if it was allocated we are passing it
2267 back (under the name of internal_relocs). */
2269 return internal_relocs;
2271 error_return:
2272 if (alloc1 != NULL)
2273 free (alloc1);
2274 if (alloc2 != NULL)
2276 if (keep_memory)
2277 bfd_release (abfd, alloc2);
2278 else
2279 free (alloc2);
2281 return NULL;
2284 /* Compute the size of, and allocate space for, REL_HDR which is the
2285 section header for a section containing relocations for O. */
2287 static bfd_boolean
2288 _bfd_elf_link_size_reloc_section (bfd *abfd,
2289 Elf_Internal_Shdr *rel_hdr,
2290 asection *o)
2292 bfd_size_type reloc_count;
2293 bfd_size_type num_rel_hashes;
2295 /* Figure out how many relocations there will be. */
2296 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2297 reloc_count = elf_section_data (o)->rel_count;
2298 else
2299 reloc_count = elf_section_data (o)->rel_count2;
2301 num_rel_hashes = o->reloc_count;
2302 if (num_rel_hashes < reloc_count)
2303 num_rel_hashes = reloc_count;
2305 /* That allows us to calculate the size of the section. */
2306 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2308 /* The contents field must last into write_object_contents, so we
2309 allocate it with bfd_alloc rather than malloc. Also since we
2310 cannot be sure that the contents will actually be filled in,
2311 we zero the allocated space. */
2312 rel_hdr->contents = (unsigned char *) bfd_zalloc (abfd, rel_hdr->sh_size);
2313 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2314 return FALSE;
2316 /* We only allocate one set of hash entries, so we only do it the
2317 first time we are called. */
2318 if (elf_section_data (o)->rel_hashes == NULL
2319 && num_rel_hashes)
2321 struct elf_link_hash_entry **p;
2323 p = (struct elf_link_hash_entry **)
2324 bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2325 if (p == NULL)
2326 return FALSE;
2328 elf_section_data (o)->rel_hashes = p;
2331 return TRUE;
2334 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2335 originated from the section given by INPUT_REL_HDR) to the
2336 OUTPUT_BFD. */
2338 bfd_boolean
2339 _bfd_elf_link_output_relocs (bfd *output_bfd,
2340 asection *input_section,
2341 Elf_Internal_Shdr *input_rel_hdr,
2342 Elf_Internal_Rela *internal_relocs,
2343 struct elf_link_hash_entry **rel_hash
2344 ATTRIBUTE_UNUSED)
2346 Elf_Internal_Rela *irela;
2347 Elf_Internal_Rela *irelaend;
2348 bfd_byte *erel;
2349 Elf_Internal_Shdr *output_rel_hdr;
2350 asection *output_section;
2351 unsigned int *rel_countp = NULL;
2352 const struct elf_backend_data *bed;
2353 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2355 output_section = input_section->output_section;
2356 output_rel_hdr = NULL;
2358 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2359 == input_rel_hdr->sh_entsize)
2361 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2362 rel_countp = &elf_section_data (output_section)->rel_count;
2364 else if (elf_section_data (output_section)->rel_hdr2
2365 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2366 == input_rel_hdr->sh_entsize))
2368 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2369 rel_countp = &elf_section_data (output_section)->rel_count2;
2371 else
2373 (*_bfd_error_handler)
2374 (_("%B: relocation size mismatch in %B section %A"),
2375 output_bfd, input_section->owner, input_section);
2376 bfd_set_error (bfd_error_wrong_format);
2377 return FALSE;
2380 bed = get_elf_backend_data (output_bfd);
2381 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2382 swap_out = bed->s->swap_reloc_out;
2383 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2384 swap_out = bed->s->swap_reloca_out;
2385 else
2386 abort ();
2388 erel = output_rel_hdr->contents;
2389 erel += *rel_countp * input_rel_hdr->sh_entsize;
2390 irela = internal_relocs;
2391 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2392 * bed->s->int_rels_per_ext_rel);
2393 while (irela < irelaend)
2395 (*swap_out) (output_bfd, irela, erel);
2396 irela += bed->s->int_rels_per_ext_rel;
2397 erel += input_rel_hdr->sh_entsize;
2400 /* Bump the counter, so that we know where to add the next set of
2401 relocations. */
2402 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2404 return TRUE;
2407 /* Make weak undefined symbols in PIE dynamic. */
2409 bfd_boolean
2410 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2411 struct elf_link_hash_entry *h)
2413 if (info->pie
2414 && h->dynindx == -1
2415 && h->root.type == bfd_link_hash_undefweak)
2416 return bfd_elf_link_record_dynamic_symbol (info, h);
2418 return TRUE;
2421 /* Fix up the flags for a symbol. This handles various cases which
2422 can only be fixed after all the input files are seen. This is
2423 currently called by both adjust_dynamic_symbol and
2424 assign_sym_version, which is unnecessary but perhaps more robust in
2425 the face of future changes. */
2427 static bfd_boolean
2428 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2429 struct elf_info_failed *eif)
2431 const struct elf_backend_data *bed;
2433 /* If this symbol was mentioned in a non-ELF file, try to set
2434 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2435 permit a non-ELF file to correctly refer to a symbol defined in
2436 an ELF dynamic object. */
2437 if (h->non_elf)
2439 while (h->root.type == bfd_link_hash_indirect)
2440 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2442 if (h->root.type != bfd_link_hash_defined
2443 && h->root.type != bfd_link_hash_defweak)
2445 h->ref_regular = 1;
2446 h->ref_regular_nonweak = 1;
2448 else
2450 if (h->root.u.def.section->owner != NULL
2451 && (bfd_get_flavour (h->root.u.def.section->owner)
2452 == bfd_target_elf_flavour))
2454 h->ref_regular = 1;
2455 h->ref_regular_nonweak = 1;
2457 else
2458 h->def_regular = 1;
2461 if (h->dynindx == -1
2462 && (h->def_dynamic
2463 || h->ref_dynamic))
2465 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2467 eif->failed = TRUE;
2468 return FALSE;
2472 else
2474 /* Unfortunately, NON_ELF is only correct if the symbol
2475 was first seen in a non-ELF file. Fortunately, if the symbol
2476 was first seen in an ELF file, we're probably OK unless the
2477 symbol was defined in a non-ELF file. Catch that case here.
2478 FIXME: We're still in trouble if the symbol was first seen in
2479 a dynamic object, and then later in a non-ELF regular object. */
2480 if ((h->root.type == bfd_link_hash_defined
2481 || h->root.type == bfd_link_hash_defweak)
2482 && !h->def_regular
2483 && (h->root.u.def.section->owner != NULL
2484 ? (bfd_get_flavour (h->root.u.def.section->owner)
2485 != bfd_target_elf_flavour)
2486 : (bfd_is_abs_section (h->root.u.def.section)
2487 && !h->def_dynamic)))
2488 h->def_regular = 1;
2491 /* Backend specific symbol fixup. */
2492 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2493 if (bed->elf_backend_fixup_symbol
2494 && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
2495 return FALSE;
2497 /* If this is a final link, and the symbol was defined as a common
2498 symbol in a regular object file, and there was no definition in
2499 any dynamic object, then the linker will have allocated space for
2500 the symbol in a common section but the DEF_REGULAR
2501 flag will not have been set. */
2502 if (h->root.type == bfd_link_hash_defined
2503 && !h->def_regular
2504 && h->ref_regular
2505 && !h->def_dynamic
2506 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2507 h->def_regular = 1;
2509 /* If -Bsymbolic was used (which means to bind references to global
2510 symbols to the definition within the shared object), and this
2511 symbol was defined in a regular object, then it actually doesn't
2512 need a PLT entry. Likewise, if the symbol has non-default
2513 visibility. If the symbol has hidden or internal visibility, we
2514 will force it local. */
2515 if (h->needs_plt
2516 && eif->info->shared
2517 && is_elf_hash_table (eif->info->hash)
2518 && (SYMBOLIC_BIND (eif->info, h)
2519 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2520 && h->def_regular)
2522 bfd_boolean force_local;
2524 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2525 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2526 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2529 /* If a weak undefined symbol has non-default visibility, we also
2530 hide it from the dynamic linker. */
2531 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2532 && h->root.type == bfd_link_hash_undefweak)
2533 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2535 /* If this is a weak defined symbol in a dynamic object, and we know
2536 the real definition in the dynamic object, copy interesting flags
2537 over to the real definition. */
2538 if (h->u.weakdef != NULL)
2540 struct elf_link_hash_entry *weakdef;
2542 weakdef = h->u.weakdef;
2543 if (h->root.type == bfd_link_hash_indirect)
2544 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2546 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2547 || h->root.type == bfd_link_hash_defweak);
2548 BFD_ASSERT (weakdef->def_dynamic);
2550 /* If the real definition is defined by a regular object file,
2551 don't do anything special. See the longer description in
2552 _bfd_elf_adjust_dynamic_symbol, below. */
2553 if (weakdef->def_regular)
2554 h->u.weakdef = NULL;
2555 else
2557 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2558 || weakdef->root.type == bfd_link_hash_defweak);
2559 (*bed->elf_backend_copy_indirect_symbol) (eif->info, weakdef, h);
2563 return TRUE;
2566 /* Make the backend pick a good value for a dynamic symbol. This is
2567 called via elf_link_hash_traverse, and also calls itself
2568 recursively. */
2570 static bfd_boolean
2571 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2573 struct elf_info_failed *eif = (struct elf_info_failed *) data;
2574 bfd *dynobj;
2575 const struct elf_backend_data *bed;
2577 if (! is_elf_hash_table (eif->info->hash))
2578 return FALSE;
2580 if (h->root.type == bfd_link_hash_warning)
2582 h->got = elf_hash_table (eif->info)->init_got_offset;
2583 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2585 /* When warning symbols are created, they **replace** the "real"
2586 entry in the hash table, thus we never get to see the real
2587 symbol in a hash traversal. So look at it now. */
2588 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2591 /* Ignore indirect symbols. These are added by the versioning code. */
2592 if (h->root.type == bfd_link_hash_indirect)
2593 return TRUE;
2595 /* Fix the symbol flags. */
2596 if (! _bfd_elf_fix_symbol_flags (h, eif))
2597 return FALSE;
2599 /* If this symbol does not require a PLT entry, and it is not
2600 defined by a dynamic object, or is not referenced by a regular
2601 object, ignore it. We do have to handle a weak defined symbol,
2602 even if no regular object refers to it, if we decided to add it
2603 to the dynamic symbol table. FIXME: Do we normally need to worry
2604 about symbols which are defined by one dynamic object and
2605 referenced by another one? */
2606 if (!h->needs_plt
2607 && h->type != STT_GNU_IFUNC
2608 && (h->def_regular
2609 || !h->def_dynamic
2610 || (!h->ref_regular
2611 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2613 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2614 return TRUE;
2617 /* If we've already adjusted this symbol, don't do it again. This
2618 can happen via a recursive call. */
2619 if (h->dynamic_adjusted)
2620 return TRUE;
2622 /* Don't look at this symbol again. Note that we must set this
2623 after checking the above conditions, because we may look at a
2624 symbol once, decide not to do anything, and then get called
2625 recursively later after REF_REGULAR is set below. */
2626 h->dynamic_adjusted = 1;
2628 /* If this is a weak definition, and we know a real definition, and
2629 the real symbol is not itself defined by a regular object file,
2630 then get a good value for the real definition. We handle the
2631 real symbol first, for the convenience of the backend routine.
2633 Note that there is a confusing case here. If the real definition
2634 is defined by a regular object file, we don't get the real symbol
2635 from the dynamic object, but we do get the weak symbol. If the
2636 processor backend uses a COPY reloc, then if some routine in the
2637 dynamic object changes the real symbol, we will not see that
2638 change in the corresponding weak symbol. This is the way other
2639 ELF linkers work as well, and seems to be a result of the shared
2640 library model.
2642 I will clarify this issue. Most SVR4 shared libraries define the
2643 variable _timezone and define timezone as a weak synonym. The
2644 tzset call changes _timezone. If you write
2645 extern int timezone;
2646 int _timezone = 5;
2647 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2648 you might expect that, since timezone is a synonym for _timezone,
2649 the same number will print both times. However, if the processor
2650 backend uses a COPY reloc, then actually timezone will be copied
2651 into your process image, and, since you define _timezone
2652 yourself, _timezone will not. Thus timezone and _timezone will
2653 wind up at different memory locations. The tzset call will set
2654 _timezone, leaving timezone unchanged. */
2656 if (h->u.weakdef != NULL)
2658 /* If we get to this point, we know there is an implicit
2659 reference by a regular object file via the weak symbol H.
2660 FIXME: Is this really true? What if the traversal finds
2661 H->U.WEAKDEF before it finds H? */
2662 h->u.weakdef->ref_regular = 1;
2664 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2665 return FALSE;
2668 /* If a symbol has no type and no size and does not require a PLT
2669 entry, then we are probably about to do the wrong thing here: we
2670 are probably going to create a COPY reloc for an empty object.
2671 This case can arise when a shared object is built with assembly
2672 code, and the assembly code fails to set the symbol type. */
2673 if (h->size == 0
2674 && h->type == STT_NOTYPE
2675 && !h->needs_plt)
2676 (*_bfd_error_handler)
2677 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2678 h->root.root.string);
2680 dynobj = elf_hash_table (eif->info)->dynobj;
2681 bed = get_elf_backend_data (dynobj);
2683 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2685 eif->failed = TRUE;
2686 return FALSE;
2689 return TRUE;
2692 /* Adjust the dynamic symbol, H, for copy in the dynamic bss section,
2693 DYNBSS. */
2695 bfd_boolean
2696 _bfd_elf_adjust_dynamic_copy (struct elf_link_hash_entry *h,
2697 asection *dynbss)
2699 unsigned int power_of_two;
2700 bfd_vma mask;
2701 asection *sec = h->root.u.def.section;
2703 /* The section aligment of definition is the maximum alignment
2704 requirement of symbols defined in the section. Since we don't
2705 know the symbol alignment requirement, we start with the
2706 maximum alignment and check low bits of the symbol address
2707 for the minimum alignment. */
2708 power_of_two = bfd_get_section_alignment (sec->owner, sec);
2709 mask = ((bfd_vma) 1 << power_of_two) - 1;
2710 while ((h->root.u.def.value & mask) != 0)
2712 mask >>= 1;
2713 --power_of_two;
2716 if (power_of_two > bfd_get_section_alignment (dynbss->owner,
2717 dynbss))
2719 /* Adjust the section alignment if needed. */
2720 if (! bfd_set_section_alignment (dynbss->owner, dynbss,
2721 power_of_two))
2722 return FALSE;
2725 /* We make sure that the symbol will be aligned properly. */
2726 dynbss->size = BFD_ALIGN (dynbss->size, mask + 1);
2728 /* Define the symbol as being at this point in DYNBSS. */
2729 h->root.u.def.section = dynbss;
2730 h->root.u.def.value = dynbss->size;
2732 /* Increment the size of DYNBSS to make room for the symbol. */
2733 dynbss->size += h->size;
2735 return TRUE;
2738 /* Adjust all external symbols pointing into SEC_MERGE sections
2739 to reflect the object merging within the sections. */
2741 static bfd_boolean
2742 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2744 asection *sec;
2746 if (h->root.type == bfd_link_hash_warning)
2747 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2749 if ((h->root.type == bfd_link_hash_defined
2750 || h->root.type == bfd_link_hash_defweak)
2751 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2752 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2754 bfd *output_bfd = (bfd *) data;
2756 h->root.u.def.value =
2757 _bfd_merged_section_offset (output_bfd,
2758 &h->root.u.def.section,
2759 elf_section_data (sec)->sec_info,
2760 h->root.u.def.value);
2763 return TRUE;
2766 /* Returns false if the symbol referred to by H should be considered
2767 to resolve local to the current module, and true if it should be
2768 considered to bind dynamically. */
2770 bfd_boolean
2771 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2772 struct bfd_link_info *info,
2773 bfd_boolean ignore_protected)
2775 bfd_boolean binding_stays_local_p;
2776 const struct elf_backend_data *bed;
2777 struct elf_link_hash_table *hash_table;
2779 if (h == NULL)
2780 return FALSE;
2782 while (h->root.type == bfd_link_hash_indirect
2783 || h->root.type == bfd_link_hash_warning)
2784 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2786 /* If it was forced local, then clearly it's not dynamic. */
2787 if (h->dynindx == -1)
2788 return FALSE;
2789 if (h->forced_local)
2790 return FALSE;
2792 /* Identify the cases where name binding rules say that a
2793 visible symbol resolves locally. */
2794 binding_stays_local_p = info->executable || SYMBOLIC_BIND (info, h);
2796 switch (ELF_ST_VISIBILITY (h->other))
2798 case STV_INTERNAL:
2799 case STV_HIDDEN:
2800 return FALSE;
2802 case STV_PROTECTED:
2803 hash_table = elf_hash_table (info);
2804 if (!is_elf_hash_table (hash_table))
2805 return FALSE;
2807 bed = get_elf_backend_data (hash_table->dynobj);
2809 /* Proper resolution for function pointer equality may require
2810 that these symbols perhaps be resolved dynamically, even though
2811 we should be resolving them to the current module. */
2812 if (!ignore_protected || !bed->is_function_type (h->type))
2813 binding_stays_local_p = TRUE;
2814 break;
2816 default:
2817 break;
2820 /* If it isn't defined locally, then clearly it's dynamic. */
2821 if (!h->def_regular)
2822 return TRUE;
2824 /* Otherwise, the symbol is dynamic if binding rules don't tell
2825 us that it remains local. */
2826 return !binding_stays_local_p;
2829 /* Return true if the symbol referred to by H should be considered
2830 to resolve local to the current module, and false otherwise. Differs
2831 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2832 undefined symbols and weak symbols. */
2834 bfd_boolean
2835 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2836 struct bfd_link_info *info,
2837 bfd_boolean local_protected)
2839 const struct elf_backend_data *bed;
2840 struct elf_link_hash_table *hash_table;
2842 /* If it's a local sym, of course we resolve locally. */
2843 if (h == NULL)
2844 return TRUE;
2846 /* STV_HIDDEN or STV_INTERNAL ones must be local. */
2847 if (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
2848 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL)
2849 return TRUE;
2851 /* Common symbols that become definitions don't get the DEF_REGULAR
2852 flag set, so test it first, and don't bail out. */
2853 if (ELF_COMMON_DEF_P (h))
2854 /* Do nothing. */;
2855 /* If we don't have a definition in a regular file, then we can't
2856 resolve locally. The sym is either undefined or dynamic. */
2857 else if (!h->def_regular)
2858 return FALSE;
2860 /* Forced local symbols resolve locally. */
2861 if (h->forced_local)
2862 return TRUE;
2864 /* As do non-dynamic symbols. */
2865 if (h->dynindx == -1)
2866 return TRUE;
2868 /* At this point, we know the symbol is defined and dynamic. In an
2869 executable it must resolve locally, likewise when building symbolic
2870 shared libraries. */
2871 if (info->executable || SYMBOLIC_BIND (info, h))
2872 return TRUE;
2874 /* Now deal with defined dynamic symbols in shared libraries. Ones
2875 with default visibility might not resolve locally. */
2876 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2877 return FALSE;
2879 hash_table = elf_hash_table (info);
2880 if (!is_elf_hash_table (hash_table))
2881 return TRUE;
2883 bed = get_elf_backend_data (hash_table->dynobj);
2885 /* STV_PROTECTED non-function symbols are local. */
2886 if (!bed->is_function_type (h->type))
2887 return TRUE;
2889 /* Function pointer equality tests may require that STV_PROTECTED
2890 symbols be treated as dynamic symbols, even when we know that the
2891 dynamic linker will resolve them locally. */
2892 return local_protected;
2895 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2896 aligned. Returns the first TLS output section. */
2898 struct bfd_section *
2899 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2901 struct bfd_section *sec, *tls;
2902 unsigned int align = 0;
2904 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2905 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2906 break;
2907 tls = sec;
2909 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2910 if (sec->alignment_power > align)
2911 align = sec->alignment_power;
2913 elf_hash_table (info)->tls_sec = tls;
2915 /* Ensure the alignment of the first section is the largest alignment,
2916 so that the tls segment starts aligned. */
2917 if (tls != NULL)
2918 tls->alignment_power = align;
2920 return tls;
2923 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2924 static bfd_boolean
2925 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2926 Elf_Internal_Sym *sym)
2928 const struct elf_backend_data *bed;
2930 /* Local symbols do not count, but target specific ones might. */
2931 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2932 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2933 return FALSE;
2935 bed = get_elf_backend_data (abfd);
2936 /* Function symbols do not count. */
2937 if (bed->is_function_type (ELF_ST_TYPE (sym->st_info)))
2938 return FALSE;
2940 /* If the section is undefined, then so is the symbol. */
2941 if (sym->st_shndx == SHN_UNDEF)
2942 return FALSE;
2944 /* If the symbol is defined in the common section, then
2945 it is a common definition and so does not count. */
2946 if (bed->common_definition (sym))
2947 return FALSE;
2949 /* If the symbol is in a target specific section then we
2950 must rely upon the backend to tell us what it is. */
2951 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2952 /* FIXME - this function is not coded yet:
2954 return _bfd_is_global_symbol_definition (abfd, sym);
2956 Instead for now assume that the definition is not global,
2957 Even if this is wrong, at least the linker will behave
2958 in the same way that it used to do. */
2959 return FALSE;
2961 return TRUE;
2964 /* Search the symbol table of the archive element of the archive ABFD
2965 whose archive map contains a mention of SYMDEF, and determine if
2966 the symbol is defined in this element. */
2967 static bfd_boolean
2968 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2970 Elf_Internal_Shdr * hdr;
2971 bfd_size_type symcount;
2972 bfd_size_type extsymcount;
2973 bfd_size_type extsymoff;
2974 Elf_Internal_Sym *isymbuf;
2975 Elf_Internal_Sym *isym;
2976 Elf_Internal_Sym *isymend;
2977 bfd_boolean result;
2979 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2980 if (abfd == NULL)
2981 return FALSE;
2983 if (! bfd_check_format (abfd, bfd_object))
2984 return FALSE;
2986 /* If we have already included the element containing this symbol in the
2987 link then we do not need to include it again. Just claim that any symbol
2988 it contains is not a definition, so that our caller will not decide to
2989 (re)include this element. */
2990 if (abfd->archive_pass)
2991 return FALSE;
2993 /* Select the appropriate symbol table. */
2994 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2995 hdr = &elf_tdata (abfd)->symtab_hdr;
2996 else
2997 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2999 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
3001 /* The sh_info field of the symtab header tells us where the
3002 external symbols start. We don't care about the local symbols. */
3003 if (elf_bad_symtab (abfd))
3005 extsymcount = symcount;
3006 extsymoff = 0;
3008 else
3010 extsymcount = symcount - hdr->sh_info;
3011 extsymoff = hdr->sh_info;
3014 if (extsymcount == 0)
3015 return FALSE;
3017 /* Read in the symbol table. */
3018 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3019 NULL, NULL, NULL);
3020 if (isymbuf == NULL)
3021 return FALSE;
3023 /* Scan the symbol table looking for SYMDEF. */
3024 result = FALSE;
3025 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
3027 const char *name;
3029 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3030 isym->st_name);
3031 if (name == NULL)
3032 break;
3034 if (strcmp (name, symdef->name) == 0)
3036 result = is_global_data_symbol_definition (abfd, isym);
3037 break;
3041 free (isymbuf);
3043 return result;
3046 /* Add an entry to the .dynamic table. */
3048 bfd_boolean
3049 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
3050 bfd_vma tag,
3051 bfd_vma val)
3053 struct elf_link_hash_table *hash_table;
3054 const struct elf_backend_data *bed;
3055 asection *s;
3056 bfd_size_type newsize;
3057 bfd_byte *newcontents;
3058 Elf_Internal_Dyn dyn;
3060 hash_table = elf_hash_table (info);
3061 if (! is_elf_hash_table (hash_table))
3062 return FALSE;
3064 bed = get_elf_backend_data (hash_table->dynobj);
3065 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
3066 BFD_ASSERT (s != NULL);
3068 newsize = s->size + bed->s->sizeof_dyn;
3069 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
3070 if (newcontents == NULL)
3071 return FALSE;
3073 dyn.d_tag = tag;
3074 dyn.d_un.d_val = val;
3075 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
3077 s->size = newsize;
3078 s->contents = newcontents;
3080 return TRUE;
3083 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
3084 otherwise just check whether one already exists. Returns -1 on error,
3085 1 if a DT_NEEDED tag already exists, and 0 on success. */
3087 static int
3088 elf_add_dt_needed_tag (bfd *abfd,
3089 struct bfd_link_info *info,
3090 const char *soname,
3091 bfd_boolean do_it)
3093 struct elf_link_hash_table *hash_table;
3094 bfd_size_type oldsize;
3095 bfd_size_type strindex;
3097 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
3098 return -1;
3100 hash_table = elf_hash_table (info);
3101 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
3102 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
3103 if (strindex == (bfd_size_type) -1)
3104 return -1;
3106 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
3108 asection *sdyn;
3109 const struct elf_backend_data *bed;
3110 bfd_byte *extdyn;
3112 bed = get_elf_backend_data (hash_table->dynobj);
3113 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
3114 if (sdyn != NULL)
3115 for (extdyn = sdyn->contents;
3116 extdyn < sdyn->contents + sdyn->size;
3117 extdyn += bed->s->sizeof_dyn)
3119 Elf_Internal_Dyn dyn;
3121 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3122 if (dyn.d_tag == DT_NEEDED
3123 && dyn.d_un.d_val == strindex)
3125 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3126 return 1;
3131 if (do_it)
3133 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
3134 return -1;
3136 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
3137 return -1;
3139 else
3140 /* We were just checking for existence of the tag. */
3141 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3143 return 0;
3146 static bfd_boolean
3147 on_needed_list (const char *soname, struct bfd_link_needed_list *needed)
3149 for (; needed != NULL; needed = needed->next)
3150 if (strcmp (soname, needed->name) == 0)
3151 return TRUE;
3153 return FALSE;
3156 /* Sort symbol by value and section. */
3157 static int
3158 elf_sort_symbol (const void *arg1, const void *arg2)
3160 const struct elf_link_hash_entry *h1;
3161 const struct elf_link_hash_entry *h2;
3162 bfd_signed_vma vdiff;
3164 h1 = *(const struct elf_link_hash_entry **) arg1;
3165 h2 = *(const struct elf_link_hash_entry **) arg2;
3166 vdiff = h1->root.u.def.value - h2->root.u.def.value;
3167 if (vdiff != 0)
3168 return vdiff > 0 ? 1 : -1;
3169 else
3171 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
3172 if (sdiff != 0)
3173 return sdiff > 0 ? 1 : -1;
3175 return 0;
3178 /* This function is used to adjust offsets into .dynstr for
3179 dynamic symbols. This is called via elf_link_hash_traverse. */
3181 static bfd_boolean
3182 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3184 struct elf_strtab_hash *dynstr = (struct elf_strtab_hash *) data;
3186 if (h->root.type == bfd_link_hash_warning)
3187 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3189 if (h->dynindx != -1)
3190 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3191 return TRUE;
3194 /* Assign string offsets in .dynstr, update all structures referencing
3195 them. */
3197 static bfd_boolean
3198 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3200 struct elf_link_hash_table *hash_table = elf_hash_table (info);
3201 struct elf_link_local_dynamic_entry *entry;
3202 struct elf_strtab_hash *dynstr = hash_table->dynstr;
3203 bfd *dynobj = hash_table->dynobj;
3204 asection *sdyn;
3205 bfd_size_type size;
3206 const struct elf_backend_data *bed;
3207 bfd_byte *extdyn;
3209 _bfd_elf_strtab_finalize (dynstr);
3210 size = _bfd_elf_strtab_size (dynstr);
3212 bed = get_elf_backend_data (dynobj);
3213 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3214 BFD_ASSERT (sdyn != NULL);
3216 /* Update all .dynamic entries referencing .dynstr strings. */
3217 for (extdyn = sdyn->contents;
3218 extdyn < sdyn->contents + sdyn->size;
3219 extdyn += bed->s->sizeof_dyn)
3221 Elf_Internal_Dyn dyn;
3223 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3224 switch (dyn.d_tag)
3226 case DT_STRSZ:
3227 dyn.d_un.d_val = size;
3228 break;
3229 case DT_NEEDED:
3230 case DT_SONAME:
3231 case DT_RPATH:
3232 case DT_RUNPATH:
3233 case DT_FILTER:
3234 case DT_AUXILIARY:
3235 case DT_AUDIT:
3236 case DT_DEPAUDIT:
3237 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3238 break;
3239 default:
3240 continue;
3242 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3245 /* Now update local dynamic symbols. */
3246 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3247 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3248 entry->isym.st_name);
3250 /* And the rest of dynamic symbols. */
3251 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3253 /* Adjust version definitions. */
3254 if (elf_tdata (output_bfd)->cverdefs)
3256 asection *s;
3257 bfd_byte *p;
3258 bfd_size_type i;
3259 Elf_Internal_Verdef def;
3260 Elf_Internal_Verdaux defaux;
3262 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3263 p = s->contents;
3266 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3267 &def);
3268 p += sizeof (Elf_External_Verdef);
3269 if (def.vd_aux != sizeof (Elf_External_Verdef))
3270 continue;
3271 for (i = 0; i < def.vd_cnt; ++i)
3273 _bfd_elf_swap_verdaux_in (output_bfd,
3274 (Elf_External_Verdaux *) p, &defaux);
3275 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3276 defaux.vda_name);
3277 _bfd_elf_swap_verdaux_out (output_bfd,
3278 &defaux, (Elf_External_Verdaux *) p);
3279 p += sizeof (Elf_External_Verdaux);
3282 while (def.vd_next);
3285 /* Adjust version references. */
3286 if (elf_tdata (output_bfd)->verref)
3288 asection *s;
3289 bfd_byte *p;
3290 bfd_size_type i;
3291 Elf_Internal_Verneed need;
3292 Elf_Internal_Vernaux needaux;
3294 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3295 p = s->contents;
3298 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3299 &need);
3300 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3301 _bfd_elf_swap_verneed_out (output_bfd, &need,
3302 (Elf_External_Verneed *) p);
3303 p += sizeof (Elf_External_Verneed);
3304 for (i = 0; i < need.vn_cnt; ++i)
3306 _bfd_elf_swap_vernaux_in (output_bfd,
3307 (Elf_External_Vernaux *) p, &needaux);
3308 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3309 needaux.vna_name);
3310 _bfd_elf_swap_vernaux_out (output_bfd,
3311 &needaux,
3312 (Elf_External_Vernaux *) p);
3313 p += sizeof (Elf_External_Vernaux);
3316 while (need.vn_next);
3319 return TRUE;
3322 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3323 The default is to only match when the INPUT and OUTPUT are exactly
3324 the same target. */
3326 bfd_boolean
3327 _bfd_elf_default_relocs_compatible (const bfd_target *input,
3328 const bfd_target *output)
3330 return input == output;
3333 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3334 This version is used when different targets for the same architecture
3335 are virtually identical. */
3337 bfd_boolean
3338 _bfd_elf_relocs_compatible (const bfd_target *input,
3339 const bfd_target *output)
3341 const struct elf_backend_data *obed, *ibed;
3343 if (input == output)
3344 return TRUE;
3346 ibed = xvec_get_elf_backend_data (input);
3347 obed = xvec_get_elf_backend_data (output);
3349 if (ibed->arch != obed->arch)
3350 return FALSE;
3352 /* If both backends are using this function, deem them compatible. */
3353 return ibed->relocs_compatible == obed->relocs_compatible;
3356 /* Add symbols from an ELF object file to the linker hash table. */
3358 static bfd_boolean
3359 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3361 Elf_Internal_Ehdr *ehdr;
3362 Elf_Internal_Shdr *hdr;
3363 bfd_size_type symcount;
3364 bfd_size_type extsymcount;
3365 bfd_size_type extsymoff;
3366 struct elf_link_hash_entry **sym_hash;
3367 bfd_boolean dynamic;
3368 Elf_External_Versym *extversym = NULL;
3369 Elf_External_Versym *ever;
3370 struct elf_link_hash_entry *weaks;
3371 struct elf_link_hash_entry **nondeflt_vers = NULL;
3372 bfd_size_type nondeflt_vers_cnt = 0;
3373 Elf_Internal_Sym *isymbuf = NULL;
3374 Elf_Internal_Sym *isym;
3375 Elf_Internal_Sym *isymend;
3376 const struct elf_backend_data *bed;
3377 bfd_boolean add_needed;
3378 struct elf_link_hash_table *htab;
3379 bfd_size_type amt;
3380 void *alloc_mark = NULL;
3381 struct bfd_hash_entry **old_table = NULL;
3382 unsigned int old_size = 0;
3383 unsigned int old_count = 0;
3384 void *old_tab = NULL;
3385 void *old_hash;
3386 void *old_ent;
3387 struct bfd_link_hash_entry *old_undefs = NULL;
3388 struct bfd_link_hash_entry *old_undefs_tail = NULL;
3389 long old_dynsymcount = 0;
3390 size_t tabsize = 0;
3391 size_t hashsize = 0;
3393 htab = elf_hash_table (info);
3394 bed = get_elf_backend_data (abfd);
3396 if ((abfd->flags & DYNAMIC) == 0)
3397 dynamic = FALSE;
3398 else
3400 dynamic = TRUE;
3402 /* You can't use -r against a dynamic object. Also, there's no
3403 hope of using a dynamic object which does not exactly match
3404 the format of the output file. */
3405 if (info->relocatable
3406 || !is_elf_hash_table (htab)
3407 || info->output_bfd->xvec != abfd->xvec)
3409 if (info->relocatable)
3410 bfd_set_error (bfd_error_invalid_operation);
3411 else
3412 bfd_set_error (bfd_error_wrong_format);
3413 goto error_return;
3417 ehdr = elf_elfheader (abfd);
3418 if (info->warn_alternate_em
3419 && bed->elf_machine_code != ehdr->e_machine
3420 && ((bed->elf_machine_alt1 != 0
3421 && ehdr->e_machine == bed->elf_machine_alt1)
3422 || (bed->elf_machine_alt2 != 0
3423 && ehdr->e_machine == bed->elf_machine_alt2)))
3424 info->callbacks->einfo
3425 (_("%P: alternate ELF machine code found (%d) in %B, expecting %d\n"),
3426 ehdr->e_machine, abfd, bed->elf_machine_code);
3428 /* As a GNU extension, any input sections which are named
3429 .gnu.warning.SYMBOL are treated as warning symbols for the given
3430 symbol. This differs from .gnu.warning sections, which generate
3431 warnings when they are included in an output file. */
3432 if (info->executable)
3434 asection *s;
3436 for (s = abfd->sections; s != NULL; s = s->next)
3438 const char *name;
3440 name = bfd_get_section_name (abfd, s);
3441 if (CONST_STRNEQ (name, ".gnu.warning."))
3443 char *msg;
3444 bfd_size_type sz;
3446 name += sizeof ".gnu.warning." - 1;
3448 /* If this is a shared object, then look up the symbol
3449 in the hash table. If it is there, and it is already
3450 been defined, then we will not be using the entry
3451 from this shared object, so we don't need to warn.
3452 FIXME: If we see the definition in a regular object
3453 later on, we will warn, but we shouldn't. The only
3454 fix is to keep track of what warnings we are supposed
3455 to emit, and then handle them all at the end of the
3456 link. */
3457 if (dynamic)
3459 struct elf_link_hash_entry *h;
3461 h = elf_link_hash_lookup (htab, name, FALSE, FALSE, TRUE);
3463 /* FIXME: What about bfd_link_hash_common? */
3464 if (h != NULL
3465 && (h->root.type == bfd_link_hash_defined
3466 || h->root.type == bfd_link_hash_defweak))
3468 /* We don't want to issue this warning. Clobber
3469 the section size so that the warning does not
3470 get copied into the output file. */
3471 s->size = 0;
3472 continue;
3476 sz = s->size;
3477 msg = (char *) bfd_alloc (abfd, sz + 1);
3478 if (msg == NULL)
3479 goto error_return;
3481 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3482 goto error_return;
3484 msg[sz] = '\0';
3486 if (! (_bfd_generic_link_add_one_symbol
3487 (info, abfd, name, BSF_WARNING, s, 0, msg,
3488 FALSE, bed->collect, NULL)))
3489 goto error_return;
3491 if (! info->relocatable)
3493 /* Clobber the section size so that the warning does
3494 not get copied into the output file. */
3495 s->size = 0;
3497 /* Also set SEC_EXCLUDE, so that symbols defined in
3498 the warning section don't get copied to the output. */
3499 s->flags |= SEC_EXCLUDE;
3505 add_needed = TRUE;
3506 if (! dynamic)
3508 /* If we are creating a shared library, create all the dynamic
3509 sections immediately. We need to attach them to something,
3510 so we attach them to this BFD, provided it is the right
3511 format. FIXME: If there are no input BFD's of the same
3512 format as the output, we can't make a shared library. */
3513 if (info->shared
3514 && is_elf_hash_table (htab)
3515 && info->output_bfd->xvec == abfd->xvec
3516 && !htab->dynamic_sections_created)
3518 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3519 goto error_return;
3522 else if (!is_elf_hash_table (htab))
3523 goto error_return;
3524 else
3526 asection *s;
3527 const char *soname = NULL;
3528 char *audit = NULL;
3529 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3530 int ret;
3532 /* ld --just-symbols and dynamic objects don't mix very well.
3533 ld shouldn't allow it. */
3534 if ((s = abfd->sections) != NULL
3535 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3536 abort ();
3538 /* If this dynamic lib was specified on the command line with
3539 --as-needed in effect, then we don't want to add a DT_NEEDED
3540 tag unless the lib is actually used. Similary for libs brought
3541 in by another lib's DT_NEEDED. When --no-add-needed is used
3542 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3543 any dynamic library in DT_NEEDED tags in the dynamic lib at
3544 all. */
3545 add_needed = (elf_dyn_lib_class (abfd)
3546 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3547 | DYN_NO_NEEDED)) == 0;
3549 s = bfd_get_section_by_name (abfd, ".dynamic");
3550 if (s != NULL)
3552 bfd_byte *dynbuf;
3553 bfd_byte *extdyn;
3554 unsigned int elfsec;
3555 unsigned long shlink;
3557 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3559 error_free_dyn:
3560 free (dynbuf);
3561 goto error_return;
3564 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3565 if (elfsec == SHN_BAD)
3566 goto error_free_dyn;
3567 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3569 for (extdyn = dynbuf;
3570 extdyn < dynbuf + s->size;
3571 extdyn += bed->s->sizeof_dyn)
3573 Elf_Internal_Dyn dyn;
3575 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3576 if (dyn.d_tag == DT_SONAME)
3578 unsigned int tagv = dyn.d_un.d_val;
3579 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3580 if (soname == NULL)
3581 goto error_free_dyn;
3583 if (dyn.d_tag == DT_NEEDED)
3585 struct bfd_link_needed_list *n, **pn;
3586 char *fnm, *anm;
3587 unsigned int tagv = dyn.d_un.d_val;
3589 amt = sizeof (struct bfd_link_needed_list);
3590 n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
3591 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3592 if (n == NULL || fnm == NULL)
3593 goto error_free_dyn;
3594 amt = strlen (fnm) + 1;
3595 anm = (char *) bfd_alloc (abfd, amt);
3596 if (anm == NULL)
3597 goto error_free_dyn;
3598 memcpy (anm, fnm, amt);
3599 n->name = anm;
3600 n->by = abfd;
3601 n->next = NULL;
3602 for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
3604 *pn = n;
3606 if (dyn.d_tag == DT_RUNPATH)
3608 struct bfd_link_needed_list *n, **pn;
3609 char *fnm, *anm;
3610 unsigned int tagv = dyn.d_un.d_val;
3612 amt = sizeof (struct bfd_link_needed_list);
3613 n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
3614 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3615 if (n == NULL || fnm == NULL)
3616 goto error_free_dyn;
3617 amt = strlen (fnm) + 1;
3618 anm = (char *) bfd_alloc (abfd, amt);
3619 if (anm == NULL)
3620 goto error_free_dyn;
3621 memcpy (anm, fnm, amt);
3622 n->name = anm;
3623 n->by = abfd;
3624 n->next = NULL;
3625 for (pn = & runpath;
3626 *pn != NULL;
3627 pn = &(*pn)->next)
3629 *pn = n;
3631 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3632 if (!runpath && dyn.d_tag == DT_RPATH)
3634 struct bfd_link_needed_list *n, **pn;
3635 char *fnm, *anm;
3636 unsigned int tagv = dyn.d_un.d_val;
3638 amt = sizeof (struct bfd_link_needed_list);
3639 n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
3640 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3641 if (n == NULL || fnm == NULL)
3642 goto error_free_dyn;
3643 amt = strlen (fnm) + 1;
3644 anm = (char *) bfd_alloc (abfd, amt);
3645 if (anm == NULL)
3646 goto error_free_dyn;
3647 memcpy (anm, fnm, amt);
3648 n->name = anm;
3649 n->by = abfd;
3650 n->next = NULL;
3651 for (pn = & rpath;
3652 *pn != NULL;
3653 pn = &(*pn)->next)
3655 *pn = n;
3657 if (dyn.d_tag == DT_AUDIT)
3659 unsigned int tagv = dyn.d_un.d_val;
3660 audit = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3664 free (dynbuf);
3667 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3668 frees all more recently bfd_alloc'd blocks as well. */
3669 if (runpath)
3670 rpath = runpath;
3672 if (rpath)
3674 struct bfd_link_needed_list **pn;
3675 for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
3677 *pn = rpath;
3680 /* We do not want to include any of the sections in a dynamic
3681 object in the output file. We hack by simply clobbering the
3682 list of sections in the BFD. This could be handled more
3683 cleanly by, say, a new section flag; the existing
3684 SEC_NEVER_LOAD flag is not the one we want, because that one
3685 still implies that the section takes up space in the output
3686 file. */
3687 bfd_section_list_clear (abfd);
3689 /* Find the name to use in a DT_NEEDED entry that refers to this
3690 object. If the object has a DT_SONAME entry, we use it.
3691 Otherwise, if the generic linker stuck something in
3692 elf_dt_name, we use that. Otherwise, we just use the file
3693 name. */
3694 if (soname == NULL || *soname == '\0')
3696 soname = elf_dt_name (abfd);
3697 if (soname == NULL || *soname == '\0')
3698 soname = bfd_get_filename (abfd);
3701 /* Save the SONAME because sometimes the linker emulation code
3702 will need to know it. */
3703 elf_dt_name (abfd) = soname;
3705 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3706 if (ret < 0)
3707 goto error_return;
3709 /* If we have already included this dynamic object in the
3710 link, just ignore it. There is no reason to include a
3711 particular dynamic object more than once. */
3712 if (ret > 0)
3713 return TRUE;
3715 /* Save the DT_AUDIT entry for the linker emulation code. */
3716 elf_dt_audit (abfd) = audit;
3719 /* If this is a dynamic object, we always link against the .dynsym
3720 symbol table, not the .symtab symbol table. The dynamic linker
3721 will only see the .dynsym symbol table, so there is no reason to
3722 look at .symtab for a dynamic object. */
3724 if (! dynamic || elf_dynsymtab (abfd) == 0)
3725 hdr = &elf_tdata (abfd)->symtab_hdr;
3726 else
3727 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3729 symcount = hdr->sh_size / bed->s->sizeof_sym;
3731 /* The sh_info field of the symtab header tells us where the
3732 external symbols start. We don't care about the local symbols at
3733 this point. */
3734 if (elf_bad_symtab (abfd))
3736 extsymcount = symcount;
3737 extsymoff = 0;
3739 else
3741 extsymcount = symcount - hdr->sh_info;
3742 extsymoff = hdr->sh_info;
3745 sym_hash = NULL;
3746 if (extsymcount != 0)
3748 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3749 NULL, NULL, NULL);
3750 if (isymbuf == NULL)
3751 goto error_return;
3753 /* We store a pointer to the hash table entry for each external
3754 symbol. */
3755 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3756 sym_hash = (struct elf_link_hash_entry **) bfd_alloc (abfd, amt);
3757 if (sym_hash == NULL)
3758 goto error_free_sym;
3759 elf_sym_hashes (abfd) = sym_hash;
3762 if (dynamic)
3764 /* Read in any version definitions. */
3765 if (!_bfd_elf_slurp_version_tables (abfd,
3766 info->default_imported_symver))
3767 goto error_free_sym;
3769 /* Read in the symbol versions, but don't bother to convert them
3770 to internal format. */
3771 if (elf_dynversym (abfd) != 0)
3773 Elf_Internal_Shdr *versymhdr;
3775 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3776 extversym = (Elf_External_Versym *) bfd_malloc (versymhdr->sh_size);
3777 if (extversym == NULL)
3778 goto error_free_sym;
3779 amt = versymhdr->sh_size;
3780 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3781 || bfd_bread (extversym, amt, abfd) != amt)
3782 goto error_free_vers;
3786 /* If we are loading an as-needed shared lib, save the symbol table
3787 state before we start adding symbols. If the lib turns out
3788 to be unneeded, restore the state. */
3789 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
3791 unsigned int i;
3792 size_t entsize;
3794 for (entsize = 0, i = 0; i < htab->root.table.size; i++)
3796 struct bfd_hash_entry *p;
3797 struct elf_link_hash_entry *h;
3799 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3801 h = (struct elf_link_hash_entry *) p;
3802 entsize += htab->root.table.entsize;
3803 if (h->root.type == bfd_link_hash_warning)
3804 entsize += htab->root.table.entsize;
3808 tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
3809 hashsize = extsymcount * sizeof (struct elf_link_hash_entry *);
3810 old_tab = bfd_malloc (tabsize + entsize + hashsize);
3811 if (old_tab == NULL)
3812 goto error_free_vers;
3814 /* Remember the current objalloc pointer, so that all mem for
3815 symbols added can later be reclaimed. */
3816 alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
3817 if (alloc_mark == NULL)
3818 goto error_free_vers;
3820 /* Make a special call to the linker "notice" function to
3821 tell it that we are about to handle an as-needed lib. */
3822 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
3823 notice_as_needed))
3824 goto error_free_vers;
3826 /* Clone the symbol table and sym hashes. Remember some
3827 pointers into the symbol table, and dynamic symbol count. */
3828 old_hash = (char *) old_tab + tabsize;
3829 old_ent = (char *) old_hash + hashsize;
3830 memcpy (old_tab, htab->root.table.table, tabsize);
3831 memcpy (old_hash, sym_hash, hashsize);
3832 old_undefs = htab->root.undefs;
3833 old_undefs_tail = htab->root.undefs_tail;
3834 old_table = htab->root.table.table;
3835 old_size = htab->root.table.size;
3836 old_count = htab->root.table.count;
3837 old_dynsymcount = htab->dynsymcount;
3839 for (i = 0; i < htab->root.table.size; i++)
3841 struct bfd_hash_entry *p;
3842 struct elf_link_hash_entry *h;
3844 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3846 memcpy (old_ent, p, htab->root.table.entsize);
3847 old_ent = (char *) old_ent + htab->root.table.entsize;
3848 h = (struct elf_link_hash_entry *) p;
3849 if (h->root.type == bfd_link_hash_warning)
3851 memcpy (old_ent, h->root.u.i.link, htab->root.table.entsize);
3852 old_ent = (char *) old_ent + htab->root.table.entsize;
3858 weaks = NULL;
3859 ever = extversym != NULL ? extversym + extsymoff : NULL;
3860 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3861 isym < isymend;
3862 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3864 int bind;
3865 bfd_vma value;
3866 asection *sec, *new_sec;
3867 flagword flags;
3868 const char *name;
3869 struct elf_link_hash_entry *h;
3870 bfd_boolean definition;
3871 bfd_boolean size_change_ok;
3872 bfd_boolean type_change_ok;
3873 bfd_boolean new_weakdef;
3874 bfd_boolean override;
3875 bfd_boolean common;
3876 unsigned int old_alignment;
3877 bfd *old_bfd;
3878 bfd * undef_bfd = NULL;
3880 override = FALSE;
3882 flags = BSF_NO_FLAGS;
3883 sec = NULL;
3884 value = isym->st_value;
3885 *sym_hash = NULL;
3886 common = bed->common_definition (isym);
3888 bind = ELF_ST_BIND (isym->st_info);
3889 switch (bind)
3891 case STB_LOCAL:
3892 /* This should be impossible, since ELF requires that all
3893 global symbols follow all local symbols, and that sh_info
3894 point to the first global symbol. Unfortunately, Irix 5
3895 screws this up. */
3896 continue;
3898 case STB_GLOBAL:
3899 if (isym->st_shndx != SHN_UNDEF && !common)
3900 flags = BSF_GLOBAL;
3901 break;
3903 case STB_WEAK:
3904 flags = BSF_WEAK;
3905 break;
3907 case STB_GNU_UNIQUE:
3908 flags = BSF_GNU_UNIQUE;
3909 break;
3911 default:
3912 /* Leave it up to the processor backend. */
3913 break;
3916 if (isym->st_shndx == SHN_UNDEF)
3917 sec = bfd_und_section_ptr;
3918 else if (isym->st_shndx == SHN_ABS)
3919 sec = bfd_abs_section_ptr;
3920 else if (isym->st_shndx == SHN_COMMON)
3922 sec = bfd_com_section_ptr;
3923 /* What ELF calls the size we call the value. What ELF
3924 calls the value we call the alignment. */
3925 value = isym->st_size;
3927 else
3929 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3930 if (sec == NULL)
3931 sec = bfd_abs_section_ptr;
3932 else if (sec->kept_section)
3934 /* Symbols from discarded section are undefined. We keep
3935 its visibility. */
3936 sec = bfd_und_section_ptr;
3937 isym->st_shndx = SHN_UNDEF;
3939 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3940 value -= sec->vma;
3943 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3944 isym->st_name);
3945 if (name == NULL)
3946 goto error_free_vers;
3948 if (isym->st_shndx == SHN_COMMON
3949 && ELF_ST_TYPE (isym->st_info) == STT_TLS
3950 && !info->relocatable)
3952 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3954 if (tcomm == NULL)
3956 tcomm = bfd_make_section_with_flags (abfd, ".tcommon",
3957 (SEC_ALLOC
3958 | SEC_IS_COMMON
3959 | SEC_LINKER_CREATED
3960 | SEC_THREAD_LOCAL));
3961 if (tcomm == NULL)
3962 goto error_free_vers;
3964 sec = tcomm;
3966 else if (bed->elf_add_symbol_hook)
3968 if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
3969 &sec, &value))
3970 goto error_free_vers;
3972 /* The hook function sets the name to NULL if this symbol
3973 should be skipped for some reason. */
3974 if (name == NULL)
3975 continue;
3978 /* Sanity check that all possibilities were handled. */
3979 if (sec == NULL)
3981 bfd_set_error (bfd_error_bad_value);
3982 goto error_free_vers;
3985 if (bfd_is_und_section (sec)
3986 || bfd_is_com_section (sec))
3987 definition = FALSE;
3988 else
3989 definition = TRUE;
3991 size_change_ok = FALSE;
3992 type_change_ok = bed->type_change_ok;
3993 old_alignment = 0;
3994 old_bfd = NULL;
3995 new_sec = sec;
3997 if (is_elf_hash_table (htab))
3999 Elf_Internal_Versym iver;
4000 unsigned int vernum = 0;
4001 bfd_boolean skip;
4003 /* If this is a definition of a symbol which was previously
4004 referenced in a non-weak manner then make a note of the bfd
4005 that contained the reference. This is used if we need to
4006 refer to the source of the reference later on. */
4007 if (! bfd_is_und_section (sec))
4009 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4011 if (h != NULL
4012 && h->root.type == bfd_link_hash_undefined
4013 && h->root.u.undef.abfd)
4014 undef_bfd = h->root.u.undef.abfd;
4017 if (ever == NULL)
4019 if (info->default_imported_symver)
4020 /* Use the default symbol version created earlier. */
4021 iver.vs_vers = elf_tdata (abfd)->cverdefs;
4022 else
4023 iver.vs_vers = 0;
4025 else
4026 _bfd_elf_swap_versym_in (abfd, ever, &iver);
4028 vernum = iver.vs_vers & VERSYM_VERSION;
4030 /* If this is a hidden symbol, or if it is not version
4031 1, we append the version name to the symbol name.
4032 However, we do not modify a non-hidden absolute symbol
4033 if it is not a function, because it might be the version
4034 symbol itself. FIXME: What if it isn't? */
4035 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
4036 || (vernum > 1
4037 && (!bfd_is_abs_section (sec)
4038 || bed->is_function_type (ELF_ST_TYPE (isym->st_info)))))
4040 const char *verstr;
4041 size_t namelen, verlen, newlen;
4042 char *newname, *p;
4044 if (isym->st_shndx != SHN_UNDEF)
4046 if (vernum > elf_tdata (abfd)->cverdefs)
4047 verstr = NULL;
4048 else if (vernum > 1)
4049 verstr =
4050 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
4051 else
4052 verstr = "";
4054 if (verstr == NULL)
4056 (*_bfd_error_handler)
4057 (_("%B: %s: invalid version %u (max %d)"),
4058 abfd, name, vernum,
4059 elf_tdata (abfd)->cverdefs);
4060 bfd_set_error (bfd_error_bad_value);
4061 goto error_free_vers;
4064 else
4066 /* We cannot simply test for the number of
4067 entries in the VERNEED section since the
4068 numbers for the needed versions do not start
4069 at 0. */
4070 Elf_Internal_Verneed *t;
4072 verstr = NULL;
4073 for (t = elf_tdata (abfd)->verref;
4074 t != NULL;
4075 t = t->vn_nextref)
4077 Elf_Internal_Vernaux *a;
4079 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
4081 if (a->vna_other == vernum)
4083 verstr = a->vna_nodename;
4084 break;
4087 if (a != NULL)
4088 break;
4090 if (verstr == NULL)
4092 (*_bfd_error_handler)
4093 (_("%B: %s: invalid needed version %d"),
4094 abfd, name, vernum);
4095 bfd_set_error (bfd_error_bad_value);
4096 goto error_free_vers;
4100 namelen = strlen (name);
4101 verlen = strlen (verstr);
4102 newlen = namelen + verlen + 2;
4103 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
4104 && isym->st_shndx != SHN_UNDEF)
4105 ++newlen;
4107 newname = (char *) bfd_hash_allocate (&htab->root.table, newlen);
4108 if (newname == NULL)
4109 goto error_free_vers;
4110 memcpy (newname, name, namelen);
4111 p = newname + namelen;
4112 *p++ = ELF_VER_CHR;
4113 /* If this is a defined non-hidden version symbol,
4114 we add another @ to the name. This indicates the
4115 default version of the symbol. */
4116 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
4117 && isym->st_shndx != SHN_UNDEF)
4118 *p++ = ELF_VER_CHR;
4119 memcpy (p, verstr, verlen + 1);
4121 name = newname;
4124 /* If necessary, make a second attempt to locate the bfd
4125 containing an unresolved, non-weak reference to the
4126 current symbol. */
4127 if (! bfd_is_und_section (sec) && undef_bfd == NULL)
4129 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4131 if (h != NULL
4132 && h->root.type == bfd_link_hash_undefined
4133 && h->root.u.undef.abfd)
4134 undef_bfd = h->root.u.undef.abfd;
4137 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
4138 &value, &old_alignment,
4139 sym_hash, &skip, &override,
4140 &type_change_ok, &size_change_ok))
4141 goto error_free_vers;
4143 if (skip)
4144 continue;
4146 if (override)
4147 definition = FALSE;
4149 h = *sym_hash;
4150 while (h->root.type == bfd_link_hash_indirect
4151 || h->root.type == bfd_link_hash_warning)
4152 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4154 /* Remember the old alignment if this is a common symbol, so
4155 that we don't reduce the alignment later on. We can't
4156 check later, because _bfd_generic_link_add_one_symbol
4157 will set a default for the alignment which we want to
4158 override. We also remember the old bfd where the existing
4159 definition comes from. */
4160 switch (h->root.type)
4162 default:
4163 break;
4165 case bfd_link_hash_defined:
4166 case bfd_link_hash_defweak:
4167 old_bfd = h->root.u.def.section->owner;
4168 break;
4170 case bfd_link_hash_common:
4171 old_bfd = h->root.u.c.p->section->owner;
4172 old_alignment = h->root.u.c.p->alignment_power;
4173 break;
4176 if (elf_tdata (abfd)->verdef != NULL
4177 && ! override
4178 && vernum > 1
4179 && definition)
4180 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
4183 if (! (_bfd_generic_link_add_one_symbol
4184 (info, abfd, name, flags, sec, value, NULL, FALSE, bed->collect,
4185 (struct bfd_link_hash_entry **) sym_hash)))
4186 goto error_free_vers;
4188 h = *sym_hash;
4189 while (h->root.type == bfd_link_hash_indirect
4190 || h->root.type == bfd_link_hash_warning)
4191 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4193 *sym_hash = h;
4194 h->unique_global = (flags & BSF_GNU_UNIQUE) != 0;
4196 new_weakdef = FALSE;
4197 if (dynamic
4198 && definition
4199 && (flags & BSF_WEAK) != 0
4200 && !bed->is_function_type (ELF_ST_TYPE (isym->st_info))
4201 && is_elf_hash_table (htab)
4202 && h->u.weakdef == NULL)
4204 /* Keep a list of all weak defined non function symbols from
4205 a dynamic object, using the weakdef field. Later in this
4206 function we will set the weakdef field to the correct
4207 value. We only put non-function symbols from dynamic
4208 objects on this list, because that happens to be the only
4209 time we need to know the normal symbol corresponding to a
4210 weak symbol, and the information is time consuming to
4211 figure out. If the weakdef field is not already NULL,
4212 then this symbol was already defined by some previous
4213 dynamic object, and we will be using that previous
4214 definition anyhow. */
4216 h->u.weakdef = weaks;
4217 weaks = h;
4218 new_weakdef = TRUE;
4221 /* Set the alignment of a common symbol. */
4222 if ((common || bfd_is_com_section (sec))
4223 && h->root.type == bfd_link_hash_common)
4225 unsigned int align;
4227 if (common)
4228 align = bfd_log2 (isym->st_value);
4229 else
4231 /* The new symbol is a common symbol in a shared object.
4232 We need to get the alignment from the section. */
4233 align = new_sec->alignment_power;
4235 if (align > old_alignment
4236 /* Permit an alignment power of zero if an alignment of one
4237 is specified and no other alignments have been specified. */
4238 || (isym->st_value == 1 && old_alignment == 0))
4239 h->root.u.c.p->alignment_power = align;
4240 else
4241 h->root.u.c.p->alignment_power = old_alignment;
4244 if (is_elf_hash_table (htab))
4246 bfd_boolean dynsym;
4248 /* Check the alignment when a common symbol is involved. This
4249 can change when a common symbol is overridden by a normal
4250 definition or a common symbol is ignored due to the old
4251 normal definition. We need to make sure the maximum
4252 alignment is maintained. */
4253 if ((old_alignment || common)
4254 && h->root.type != bfd_link_hash_common)
4256 unsigned int common_align;
4257 unsigned int normal_align;
4258 unsigned int symbol_align;
4259 bfd *normal_bfd;
4260 bfd *common_bfd;
4262 symbol_align = ffs (h->root.u.def.value) - 1;
4263 if (h->root.u.def.section->owner != NULL
4264 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
4266 normal_align = h->root.u.def.section->alignment_power;
4267 if (normal_align > symbol_align)
4268 normal_align = symbol_align;
4270 else
4271 normal_align = symbol_align;
4273 if (old_alignment)
4275 common_align = old_alignment;
4276 common_bfd = old_bfd;
4277 normal_bfd = abfd;
4279 else
4281 common_align = bfd_log2 (isym->st_value);
4282 common_bfd = abfd;
4283 normal_bfd = old_bfd;
4286 if (normal_align < common_align)
4288 /* PR binutils/2735 */
4289 if (normal_bfd == NULL)
4290 (*_bfd_error_handler)
4291 (_("Warning: alignment %u of common symbol `%s' in %B"
4292 " is greater than the alignment (%u) of its section %A"),
4293 common_bfd, h->root.u.def.section,
4294 1 << common_align, name, 1 << normal_align);
4295 else
4296 (*_bfd_error_handler)
4297 (_("Warning: alignment %u of symbol `%s' in %B"
4298 " is smaller than %u in %B"),
4299 normal_bfd, common_bfd,
4300 1 << normal_align, name, 1 << common_align);
4304 /* Remember the symbol size if it isn't undefined. */
4305 if ((isym->st_size != 0 && isym->st_shndx != SHN_UNDEF)
4306 && (definition || h->size == 0))
4308 if (h->size != 0
4309 && h->size != isym->st_size
4310 && ! size_change_ok)
4311 (*_bfd_error_handler)
4312 (_("Warning: size of symbol `%s' changed"
4313 " from %lu in %B to %lu in %B"),
4314 old_bfd, abfd,
4315 name, (unsigned long) h->size,
4316 (unsigned long) isym->st_size);
4318 h->size = isym->st_size;
4321 /* If this is a common symbol, then we always want H->SIZE
4322 to be the size of the common symbol. The code just above
4323 won't fix the size if a common symbol becomes larger. We
4324 don't warn about a size change here, because that is
4325 covered by --warn-common. Allow changed between different
4326 function types. */
4327 if (h->root.type == bfd_link_hash_common)
4328 h->size = h->root.u.c.size;
4330 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
4331 && (definition || h->type == STT_NOTYPE))
4333 unsigned int type = ELF_ST_TYPE (isym->st_info);
4335 /* Turn an IFUNC symbol from a DSO into a normal FUNC
4336 symbol. */
4337 if (type == STT_GNU_IFUNC
4338 && (abfd->flags & DYNAMIC) != 0)
4339 type = STT_FUNC;
4341 if (h->type != type)
4343 if (h->type != STT_NOTYPE && ! type_change_ok)
4344 (*_bfd_error_handler)
4345 (_("Warning: type of symbol `%s' changed"
4346 " from %d to %d in %B"),
4347 abfd, name, h->type, type);
4349 h->type = type;
4353 /* Merge st_other field. */
4354 elf_merge_st_other (abfd, h, isym, definition, dynamic);
4356 /* Set a flag in the hash table entry indicating the type of
4357 reference or definition we just found. Keep a count of
4358 the number of dynamic symbols we find. A dynamic symbol
4359 is one which is referenced or defined by both a regular
4360 object and a shared object. */
4361 dynsym = FALSE;
4362 if (! dynamic)
4364 if (! definition)
4366 h->ref_regular = 1;
4367 if (bind != STB_WEAK)
4368 h->ref_regular_nonweak = 1;
4370 else
4372 h->def_regular = 1;
4373 if (h->def_dynamic)
4375 h->def_dynamic = 0;
4376 h->ref_dynamic = 1;
4377 h->dynamic_def = 1;
4380 if (! info->executable
4381 || h->def_dynamic
4382 || h->ref_dynamic)
4383 dynsym = TRUE;
4385 else
4387 if (! definition)
4388 h->ref_dynamic = 1;
4389 else
4390 h->def_dynamic = 1;
4391 if (h->def_regular
4392 || h->ref_regular
4393 || (h->u.weakdef != NULL
4394 && ! new_weakdef
4395 && h->u.weakdef->dynindx != -1))
4396 dynsym = TRUE;
4399 if (definition && (sec->flags & SEC_DEBUGGING) && !info->relocatable)
4401 /* We don't want to make debug symbol dynamic. */
4402 dynsym = FALSE;
4405 /* Check to see if we need to add an indirect symbol for
4406 the default name. */
4407 if (definition || h->root.type == bfd_link_hash_common)
4408 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4409 &sec, &value, &dynsym,
4410 override))
4411 goto error_free_vers;
4413 if (definition && !dynamic)
4415 char *p = strchr (name, ELF_VER_CHR);
4416 if (p != NULL && p[1] != ELF_VER_CHR)
4418 /* Queue non-default versions so that .symver x, x@FOO
4419 aliases can be checked. */
4420 if (!nondeflt_vers)
4422 amt = ((isymend - isym + 1)
4423 * sizeof (struct elf_link_hash_entry *));
4424 nondeflt_vers =
4425 (struct elf_link_hash_entry **) bfd_malloc (amt);
4426 if (!nondeflt_vers)
4427 goto error_free_vers;
4429 nondeflt_vers[nondeflt_vers_cnt++] = h;
4433 if (dynsym && h->dynindx == -1)
4435 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4436 goto error_free_vers;
4437 if (h->u.weakdef != NULL
4438 && ! new_weakdef
4439 && h->u.weakdef->dynindx == -1)
4441 if (!bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4442 goto error_free_vers;
4445 else if (dynsym && h->dynindx != -1)
4446 /* If the symbol already has a dynamic index, but
4447 visibility says it should not be visible, turn it into
4448 a local symbol. */
4449 switch (ELF_ST_VISIBILITY (h->other))
4451 case STV_INTERNAL:
4452 case STV_HIDDEN:
4453 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4454 dynsym = FALSE;
4455 break;
4458 if (!add_needed
4459 && definition
4460 && ((dynsym
4461 && h->ref_regular)
4462 || (h->ref_dynamic
4463 && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0
4464 && !on_needed_list (elf_dt_name (abfd), htab->needed))))
4466 int ret;
4467 const char *soname = elf_dt_name (abfd);
4469 /* A symbol from a library loaded via DT_NEEDED of some
4470 other library is referenced by a regular object.
4471 Add a DT_NEEDED entry for it. Issue an error if
4472 --no-add-needed is used and the reference was not
4473 a weak one. */
4474 if (undef_bfd != NULL
4475 && (elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4477 (*_bfd_error_handler)
4478 (_("%B: undefined reference to symbol '%s'"),
4479 undef_bfd, name);
4480 (*_bfd_error_handler)
4481 (_("note: '%s' is defined in DSO %B so try adding it to the linker command line"),
4482 abfd, name);
4483 bfd_set_error (bfd_error_invalid_operation);
4484 goto error_free_vers;
4487 elf_dyn_lib_class (abfd) = (enum dynamic_lib_link_class)
4488 (elf_dyn_lib_class (abfd) & ~DYN_AS_NEEDED);
4490 add_needed = TRUE;
4491 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4492 if (ret < 0)
4493 goto error_free_vers;
4495 BFD_ASSERT (ret == 0);
4500 if (extversym != NULL)
4502 free (extversym);
4503 extversym = NULL;
4506 if (isymbuf != NULL)
4508 free (isymbuf);
4509 isymbuf = NULL;
4512 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4514 unsigned int i;
4516 /* Restore the symbol table. */
4517 if (bed->as_needed_cleanup)
4518 (*bed->as_needed_cleanup) (abfd, info);
4519 old_hash = (char *) old_tab + tabsize;
4520 old_ent = (char *) old_hash + hashsize;
4521 sym_hash = elf_sym_hashes (abfd);
4522 htab->root.table.table = old_table;
4523 htab->root.table.size = old_size;
4524 htab->root.table.count = old_count;
4525 memcpy (htab->root.table.table, old_tab, tabsize);
4526 memcpy (sym_hash, old_hash, hashsize);
4527 htab->root.undefs = old_undefs;
4528 htab->root.undefs_tail = old_undefs_tail;
4529 for (i = 0; i < htab->root.table.size; i++)
4531 struct bfd_hash_entry *p;
4532 struct elf_link_hash_entry *h;
4534 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4536 h = (struct elf_link_hash_entry *) p;
4537 if (h->root.type == bfd_link_hash_warning)
4538 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4539 if (h->dynindx >= old_dynsymcount)
4540 _bfd_elf_strtab_delref (htab->dynstr, h->dynstr_index);
4542 memcpy (p, old_ent, htab->root.table.entsize);
4543 old_ent = (char *) old_ent + htab->root.table.entsize;
4544 h = (struct elf_link_hash_entry *) p;
4545 if (h->root.type == bfd_link_hash_warning)
4547 memcpy (h->root.u.i.link, old_ent, htab->root.table.entsize);
4548 old_ent = (char *) old_ent + htab->root.table.entsize;
4553 /* Make a special call to the linker "notice" function to
4554 tell it that symbols added for crefs may need to be removed. */
4555 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4556 notice_not_needed))
4557 goto error_free_vers;
4559 free (old_tab);
4560 objalloc_free_block ((struct objalloc *) htab->root.table.memory,
4561 alloc_mark);
4562 if (nondeflt_vers != NULL)
4563 free (nondeflt_vers);
4564 return TRUE;
4567 if (old_tab != NULL)
4569 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4570 notice_needed))
4571 goto error_free_vers;
4572 free (old_tab);
4573 old_tab = NULL;
4576 /* Now that all the symbols from this input file are created, handle
4577 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4578 if (nondeflt_vers != NULL)
4580 bfd_size_type cnt, symidx;
4582 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4584 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4585 char *shortname, *p;
4587 p = strchr (h->root.root.string, ELF_VER_CHR);
4588 if (p == NULL
4589 || (h->root.type != bfd_link_hash_defined
4590 && h->root.type != bfd_link_hash_defweak))
4591 continue;
4593 amt = p - h->root.root.string;
4594 shortname = (char *) bfd_malloc (amt + 1);
4595 if (!shortname)
4596 goto error_free_vers;
4597 memcpy (shortname, h->root.root.string, amt);
4598 shortname[amt] = '\0';
4600 hi = (struct elf_link_hash_entry *)
4601 bfd_link_hash_lookup (&htab->root, shortname,
4602 FALSE, FALSE, FALSE);
4603 if (hi != NULL
4604 && hi->root.type == h->root.type
4605 && hi->root.u.def.value == h->root.u.def.value
4606 && hi->root.u.def.section == h->root.u.def.section)
4608 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4609 hi->root.type = bfd_link_hash_indirect;
4610 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4611 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
4612 sym_hash = elf_sym_hashes (abfd);
4613 if (sym_hash)
4614 for (symidx = 0; symidx < extsymcount; ++symidx)
4615 if (sym_hash[symidx] == hi)
4617 sym_hash[symidx] = h;
4618 break;
4621 free (shortname);
4623 free (nondeflt_vers);
4624 nondeflt_vers = NULL;
4627 /* Now set the weakdefs field correctly for all the weak defined
4628 symbols we found. The only way to do this is to search all the
4629 symbols. Since we only need the information for non functions in
4630 dynamic objects, that's the only time we actually put anything on
4631 the list WEAKS. We need this information so that if a regular
4632 object refers to a symbol defined weakly in a dynamic object, the
4633 real symbol in the dynamic object is also put in the dynamic
4634 symbols; we also must arrange for both symbols to point to the
4635 same memory location. We could handle the general case of symbol
4636 aliasing, but a general symbol alias can only be generated in
4637 assembler code, handling it correctly would be very time
4638 consuming, and other ELF linkers don't handle general aliasing
4639 either. */
4640 if (weaks != NULL)
4642 struct elf_link_hash_entry **hpp;
4643 struct elf_link_hash_entry **hppend;
4644 struct elf_link_hash_entry **sorted_sym_hash;
4645 struct elf_link_hash_entry *h;
4646 size_t sym_count;
4648 /* Since we have to search the whole symbol list for each weak
4649 defined symbol, search time for N weak defined symbols will be
4650 O(N^2). Binary search will cut it down to O(NlogN). */
4651 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4652 sorted_sym_hash = (struct elf_link_hash_entry **) bfd_malloc (amt);
4653 if (sorted_sym_hash == NULL)
4654 goto error_return;
4655 sym_hash = sorted_sym_hash;
4656 hpp = elf_sym_hashes (abfd);
4657 hppend = hpp + extsymcount;
4658 sym_count = 0;
4659 for (; hpp < hppend; hpp++)
4661 h = *hpp;
4662 if (h != NULL
4663 && h->root.type == bfd_link_hash_defined
4664 && !bed->is_function_type (h->type))
4666 *sym_hash = h;
4667 sym_hash++;
4668 sym_count++;
4672 qsort (sorted_sym_hash, sym_count,
4673 sizeof (struct elf_link_hash_entry *),
4674 elf_sort_symbol);
4676 while (weaks != NULL)
4678 struct elf_link_hash_entry *hlook;
4679 asection *slook;
4680 bfd_vma vlook;
4681 long ilook;
4682 size_t i, j, idx;
4684 hlook = weaks;
4685 weaks = hlook->u.weakdef;
4686 hlook->u.weakdef = NULL;
4688 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4689 || hlook->root.type == bfd_link_hash_defweak
4690 || hlook->root.type == bfd_link_hash_common
4691 || hlook->root.type == bfd_link_hash_indirect);
4692 slook = hlook->root.u.def.section;
4693 vlook = hlook->root.u.def.value;
4695 ilook = -1;
4696 i = 0;
4697 j = sym_count;
4698 while (i < j)
4700 bfd_signed_vma vdiff;
4701 idx = (i + j) / 2;
4702 h = sorted_sym_hash [idx];
4703 vdiff = vlook - h->root.u.def.value;
4704 if (vdiff < 0)
4705 j = idx;
4706 else if (vdiff > 0)
4707 i = idx + 1;
4708 else
4710 long sdiff = slook->id - h->root.u.def.section->id;
4711 if (sdiff < 0)
4712 j = idx;
4713 else if (sdiff > 0)
4714 i = idx + 1;
4715 else
4717 ilook = idx;
4718 break;
4723 /* We didn't find a value/section match. */
4724 if (ilook == -1)
4725 continue;
4727 for (i = ilook; i < sym_count; i++)
4729 h = sorted_sym_hash [i];
4731 /* Stop if value or section doesn't match. */
4732 if (h->root.u.def.value != vlook
4733 || h->root.u.def.section != slook)
4734 break;
4735 else if (h != hlook)
4737 hlook->u.weakdef = h;
4739 /* If the weak definition is in the list of dynamic
4740 symbols, make sure the real definition is put
4741 there as well. */
4742 if (hlook->dynindx != -1 && h->dynindx == -1)
4744 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4746 err_free_sym_hash:
4747 free (sorted_sym_hash);
4748 goto error_return;
4752 /* If the real definition is in the list of dynamic
4753 symbols, make sure the weak definition is put
4754 there as well. If we don't do this, then the
4755 dynamic loader might not merge the entries for the
4756 real definition and the weak definition. */
4757 if (h->dynindx != -1 && hlook->dynindx == -1)
4759 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4760 goto err_free_sym_hash;
4762 break;
4767 free (sorted_sym_hash);
4770 if (bed->check_directives
4771 && !(*bed->check_directives) (abfd, info))
4772 return FALSE;
4774 /* If this object is the same format as the output object, and it is
4775 not a shared library, then let the backend look through the
4776 relocs.
4778 This is required to build global offset table entries and to
4779 arrange for dynamic relocs. It is not required for the
4780 particular common case of linking non PIC code, even when linking
4781 against shared libraries, but unfortunately there is no way of
4782 knowing whether an object file has been compiled PIC or not.
4783 Looking through the relocs is not particularly time consuming.
4784 The problem is that we must either (1) keep the relocs in memory,
4785 which causes the linker to require additional runtime memory or
4786 (2) read the relocs twice from the input file, which wastes time.
4787 This would be a good case for using mmap.
4789 I have no idea how to handle linking PIC code into a file of a
4790 different format. It probably can't be done. */
4791 if (! dynamic
4792 && is_elf_hash_table (htab)
4793 && bed->check_relocs != NULL
4794 && (*bed->relocs_compatible) (abfd->xvec, info->output_bfd->xvec))
4796 asection *o;
4798 for (o = abfd->sections; o != NULL; o = o->next)
4800 Elf_Internal_Rela *internal_relocs;
4801 bfd_boolean ok;
4803 if ((o->flags & SEC_RELOC) == 0
4804 || o->reloc_count == 0
4805 || ((info->strip == strip_all || info->strip == strip_debugger)
4806 && (o->flags & SEC_DEBUGGING) != 0)
4807 || bfd_is_abs_section (o->output_section))
4808 continue;
4810 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4811 info->keep_memory);
4812 if (internal_relocs == NULL)
4813 goto error_return;
4815 ok = (*bed->check_relocs) (abfd, info, o, internal_relocs);
4817 if (elf_section_data (o)->relocs != internal_relocs)
4818 free (internal_relocs);
4820 if (! ok)
4821 goto error_return;
4825 /* If this is a non-traditional link, try to optimize the handling
4826 of the .stab/.stabstr sections. */
4827 if (! dynamic
4828 && ! info->traditional_format
4829 && is_elf_hash_table (htab)
4830 && (info->strip != strip_all && info->strip != strip_debugger))
4832 asection *stabstr;
4834 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4835 if (stabstr != NULL)
4837 bfd_size_type string_offset = 0;
4838 asection *stab;
4840 for (stab = abfd->sections; stab; stab = stab->next)
4841 if (CONST_STRNEQ (stab->name, ".stab")
4842 && (!stab->name[5] ||
4843 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4844 && (stab->flags & SEC_MERGE) == 0
4845 && !bfd_is_abs_section (stab->output_section))
4847 struct bfd_elf_section_data *secdata;
4849 secdata = elf_section_data (stab);
4850 if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
4851 stabstr, &secdata->sec_info,
4852 &string_offset))
4853 goto error_return;
4854 if (secdata->sec_info)
4855 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4860 if (is_elf_hash_table (htab) && add_needed)
4862 /* Add this bfd to the loaded list. */
4863 struct elf_link_loaded_list *n;
4865 n = (struct elf_link_loaded_list *)
4866 bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4867 if (n == NULL)
4868 goto error_return;
4869 n->abfd = abfd;
4870 n->next = htab->loaded;
4871 htab->loaded = n;
4874 return TRUE;
4876 error_free_vers:
4877 if (old_tab != NULL)
4878 free (old_tab);
4879 if (nondeflt_vers != NULL)
4880 free (nondeflt_vers);
4881 if (extversym != NULL)
4882 free (extversym);
4883 error_free_sym:
4884 if (isymbuf != NULL)
4885 free (isymbuf);
4886 error_return:
4887 return FALSE;
4890 /* Return the linker hash table entry of a symbol that might be
4891 satisfied by an archive symbol. Return -1 on error. */
4893 struct elf_link_hash_entry *
4894 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4895 struct bfd_link_info *info,
4896 const char *name)
4898 struct elf_link_hash_entry *h;
4899 char *p, *copy;
4900 size_t len, first;
4902 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4903 if (h != NULL)
4904 return h;
4906 /* If this is a default version (the name contains @@), look up the
4907 symbol again with only one `@' as well as without the version.
4908 The effect is that references to the symbol with and without the
4909 version will be matched by the default symbol in the archive. */
4911 p = strchr (name, ELF_VER_CHR);
4912 if (p == NULL || p[1] != ELF_VER_CHR)
4913 return h;
4915 /* First check with only one `@'. */
4916 len = strlen (name);
4917 copy = (char *) bfd_alloc (abfd, len);
4918 if (copy == NULL)
4919 return (struct elf_link_hash_entry *) 0 - 1;
4921 first = p - name + 1;
4922 memcpy (copy, name, first);
4923 memcpy (copy + first, name + first + 1, len - first);
4925 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4926 if (h == NULL)
4928 /* We also need to check references to the symbol without the
4929 version. */
4930 copy[first - 1] = '\0';
4931 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4932 FALSE, FALSE, FALSE);
4935 bfd_release (abfd, copy);
4936 return h;
4939 /* Add symbols from an ELF archive file to the linker hash table. We
4940 don't use _bfd_generic_link_add_archive_symbols because of a
4941 problem which arises on UnixWare. The UnixWare libc.so is an
4942 archive which includes an entry libc.so.1 which defines a bunch of
4943 symbols. The libc.so archive also includes a number of other
4944 object files, which also define symbols, some of which are the same
4945 as those defined in libc.so.1. Correct linking requires that we
4946 consider each object file in turn, and include it if it defines any
4947 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4948 this; it looks through the list of undefined symbols, and includes
4949 any object file which defines them. When this algorithm is used on
4950 UnixWare, it winds up pulling in libc.so.1 early and defining a
4951 bunch of symbols. This means that some of the other objects in the
4952 archive are not included in the link, which is incorrect since they
4953 precede libc.so.1 in the archive.
4955 Fortunately, ELF archive handling is simpler than that done by
4956 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4957 oddities. In ELF, if we find a symbol in the archive map, and the
4958 symbol is currently undefined, we know that we must pull in that
4959 object file.
4961 Unfortunately, we do have to make multiple passes over the symbol
4962 table until nothing further is resolved. */
4964 static bfd_boolean
4965 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4967 symindex c;
4968 bfd_boolean *defined = NULL;
4969 bfd_boolean *included = NULL;
4970 carsym *symdefs;
4971 bfd_boolean loop;
4972 bfd_size_type amt;
4973 const struct elf_backend_data *bed;
4974 struct elf_link_hash_entry * (*archive_symbol_lookup)
4975 (bfd *, struct bfd_link_info *, const char *);
4977 if (! bfd_has_map (abfd))
4979 /* An empty archive is a special case. */
4980 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4981 return TRUE;
4982 bfd_set_error (bfd_error_no_armap);
4983 return FALSE;
4986 /* Keep track of all symbols we know to be already defined, and all
4987 files we know to be already included. This is to speed up the
4988 second and subsequent passes. */
4989 c = bfd_ardata (abfd)->symdef_count;
4990 if (c == 0)
4991 return TRUE;
4992 amt = c;
4993 amt *= sizeof (bfd_boolean);
4994 defined = (bfd_boolean *) bfd_zmalloc (amt);
4995 included = (bfd_boolean *) bfd_zmalloc (amt);
4996 if (defined == NULL || included == NULL)
4997 goto error_return;
4999 symdefs = bfd_ardata (abfd)->symdefs;
5000 bed = get_elf_backend_data (abfd);
5001 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
5005 file_ptr last;
5006 symindex i;
5007 carsym *symdef;
5008 carsym *symdefend;
5010 loop = FALSE;
5011 last = -1;
5013 symdef = symdefs;
5014 symdefend = symdef + c;
5015 for (i = 0; symdef < symdefend; symdef++, i++)
5017 struct elf_link_hash_entry *h;
5018 bfd *element;
5019 struct bfd_link_hash_entry *undefs_tail;
5020 symindex mark;
5022 if (defined[i] || included[i])
5023 continue;
5024 if (symdef->file_offset == last)
5026 included[i] = TRUE;
5027 continue;
5030 h = archive_symbol_lookup (abfd, info, symdef->name);
5031 if (h == (struct elf_link_hash_entry *) 0 - 1)
5032 goto error_return;
5034 if (h == NULL)
5035 continue;
5037 if (h->root.type == bfd_link_hash_common)
5039 /* We currently have a common symbol. The archive map contains
5040 a reference to this symbol, so we may want to include it. We
5041 only want to include it however, if this archive element
5042 contains a definition of the symbol, not just another common
5043 declaration of it.
5045 Unfortunately some archivers (including GNU ar) will put
5046 declarations of common symbols into their archive maps, as
5047 well as real definitions, so we cannot just go by the archive
5048 map alone. Instead we must read in the element's symbol
5049 table and check that to see what kind of symbol definition
5050 this is. */
5051 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
5052 continue;
5054 else if (h->root.type != bfd_link_hash_undefined)
5056 if (h->root.type != bfd_link_hash_undefweak)
5057 defined[i] = TRUE;
5058 continue;
5061 /* We need to include this archive member. */
5062 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
5063 if (element == NULL)
5064 goto error_return;
5066 if (! bfd_check_format (element, bfd_object))
5067 goto error_return;
5069 /* Doublecheck that we have not included this object
5070 already--it should be impossible, but there may be
5071 something wrong with the archive. */
5072 if (element->archive_pass != 0)
5074 bfd_set_error (bfd_error_bad_value);
5075 goto error_return;
5077 element->archive_pass = 1;
5079 undefs_tail = info->hash->undefs_tail;
5081 if (! (*info->callbacks->add_archive_element) (info, element,
5082 symdef->name))
5083 goto error_return;
5084 if (! bfd_link_add_symbols (element, info))
5085 goto error_return;
5087 /* If there are any new undefined symbols, we need to make
5088 another pass through the archive in order to see whether
5089 they can be defined. FIXME: This isn't perfect, because
5090 common symbols wind up on undefs_tail and because an
5091 undefined symbol which is defined later on in this pass
5092 does not require another pass. This isn't a bug, but it
5093 does make the code less efficient than it could be. */
5094 if (undefs_tail != info->hash->undefs_tail)
5095 loop = TRUE;
5097 /* Look backward to mark all symbols from this object file
5098 which we have already seen in this pass. */
5099 mark = i;
5102 included[mark] = TRUE;
5103 if (mark == 0)
5104 break;
5105 --mark;
5107 while (symdefs[mark].file_offset == symdef->file_offset);
5109 /* We mark subsequent symbols from this object file as we go
5110 on through the loop. */
5111 last = symdef->file_offset;
5114 while (loop);
5116 free (defined);
5117 free (included);
5119 return TRUE;
5121 error_return:
5122 if (defined != NULL)
5123 free (defined);
5124 if (included != NULL)
5125 free (included);
5126 return FALSE;
5129 /* Given an ELF BFD, add symbols to the global hash table as
5130 appropriate. */
5132 bfd_boolean
5133 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
5135 switch (bfd_get_format (abfd))
5137 case bfd_object:
5138 return elf_link_add_object_symbols (abfd, info);
5139 case bfd_archive:
5140 return elf_link_add_archive_symbols (abfd, info);
5141 default:
5142 bfd_set_error (bfd_error_wrong_format);
5143 return FALSE;
5147 struct hash_codes_info
5149 unsigned long *hashcodes;
5150 bfd_boolean error;
5153 /* This function will be called though elf_link_hash_traverse to store
5154 all hash value of the exported symbols in an array. */
5156 static bfd_boolean
5157 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
5159 struct hash_codes_info *inf = (struct hash_codes_info *) data;
5160 const char *name;
5161 char *p;
5162 unsigned long ha;
5163 char *alc = NULL;
5165 if (h->root.type == bfd_link_hash_warning)
5166 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5168 /* Ignore indirect symbols. These are added by the versioning code. */
5169 if (h->dynindx == -1)
5170 return TRUE;
5172 name = h->root.root.string;
5173 p = strchr (name, ELF_VER_CHR);
5174 if (p != NULL)
5176 alc = (char *) bfd_malloc (p - name + 1);
5177 if (alc == NULL)
5179 inf->error = TRUE;
5180 return FALSE;
5182 memcpy (alc, name, p - name);
5183 alc[p - name] = '\0';
5184 name = alc;
5187 /* Compute the hash value. */
5188 ha = bfd_elf_hash (name);
5190 /* Store the found hash value in the array given as the argument. */
5191 *(inf->hashcodes)++ = ha;
5193 /* And store it in the struct so that we can put it in the hash table
5194 later. */
5195 h->u.elf_hash_value = ha;
5197 if (alc != NULL)
5198 free (alc);
5200 return TRUE;
5203 struct collect_gnu_hash_codes
5205 bfd *output_bfd;
5206 const struct elf_backend_data *bed;
5207 unsigned long int nsyms;
5208 unsigned long int maskbits;
5209 unsigned long int *hashcodes;
5210 unsigned long int *hashval;
5211 unsigned long int *indx;
5212 unsigned long int *counts;
5213 bfd_vma *bitmask;
5214 bfd_byte *contents;
5215 long int min_dynindx;
5216 unsigned long int bucketcount;
5217 unsigned long int symindx;
5218 long int local_indx;
5219 long int shift1, shift2;
5220 unsigned long int mask;
5221 bfd_boolean error;
5224 /* This function will be called though elf_link_hash_traverse to store
5225 all hash value of the exported symbols in an array. */
5227 static bfd_boolean
5228 elf_collect_gnu_hash_codes (struct elf_link_hash_entry *h, void *data)
5230 struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
5231 const char *name;
5232 char *p;
5233 unsigned long ha;
5234 char *alc = NULL;
5236 if (h->root.type == bfd_link_hash_warning)
5237 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5239 /* Ignore indirect symbols. These are added by the versioning code. */
5240 if (h->dynindx == -1)
5241 return TRUE;
5243 /* Ignore also local symbols and undefined symbols. */
5244 if (! (*s->bed->elf_hash_symbol) (h))
5245 return TRUE;
5247 name = h->root.root.string;
5248 p = strchr (name, ELF_VER_CHR);
5249 if (p != NULL)
5251 alc = (char *) bfd_malloc (p - name + 1);
5252 if (alc == NULL)
5254 s->error = TRUE;
5255 return FALSE;
5257 memcpy (alc, name, p - name);
5258 alc[p - name] = '\0';
5259 name = alc;
5262 /* Compute the hash value. */
5263 ha = bfd_elf_gnu_hash (name);
5265 /* Store the found hash value in the array for compute_bucket_count,
5266 and also for .dynsym reordering purposes. */
5267 s->hashcodes[s->nsyms] = ha;
5268 s->hashval[h->dynindx] = ha;
5269 ++s->nsyms;
5270 if (s->min_dynindx < 0 || s->min_dynindx > h->dynindx)
5271 s->min_dynindx = h->dynindx;
5273 if (alc != NULL)
5274 free (alc);
5276 return TRUE;
5279 /* This function will be called though elf_link_hash_traverse to do
5280 final dynaminc symbol renumbering. */
5282 static bfd_boolean
5283 elf_renumber_gnu_hash_syms (struct elf_link_hash_entry *h, void *data)
5285 struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
5286 unsigned long int bucket;
5287 unsigned long int val;
5289 if (h->root.type == bfd_link_hash_warning)
5290 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5292 /* Ignore indirect symbols. */
5293 if (h->dynindx == -1)
5294 return TRUE;
5296 /* Ignore also local symbols and undefined symbols. */
5297 if (! (*s->bed->elf_hash_symbol) (h))
5299 if (h->dynindx >= s->min_dynindx)
5300 h->dynindx = s->local_indx++;
5301 return TRUE;
5304 bucket = s->hashval[h->dynindx] % s->bucketcount;
5305 val = (s->hashval[h->dynindx] >> s->shift1)
5306 & ((s->maskbits >> s->shift1) - 1);
5307 s->bitmask[val] |= ((bfd_vma) 1) << (s->hashval[h->dynindx] & s->mask);
5308 s->bitmask[val]
5309 |= ((bfd_vma) 1) << ((s->hashval[h->dynindx] >> s->shift2) & s->mask);
5310 val = s->hashval[h->dynindx] & ~(unsigned long int) 1;
5311 if (s->counts[bucket] == 1)
5312 /* Last element terminates the chain. */
5313 val |= 1;
5314 bfd_put_32 (s->output_bfd, val,
5315 s->contents + (s->indx[bucket] - s->symindx) * 4);
5316 --s->counts[bucket];
5317 h->dynindx = s->indx[bucket]++;
5318 return TRUE;
5321 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
5323 bfd_boolean
5324 _bfd_elf_hash_symbol (struct elf_link_hash_entry *h)
5326 return !(h->forced_local
5327 || h->root.type == bfd_link_hash_undefined
5328 || h->root.type == bfd_link_hash_undefweak
5329 || ((h->root.type == bfd_link_hash_defined
5330 || h->root.type == bfd_link_hash_defweak)
5331 && h->root.u.def.section->output_section == NULL));
5334 /* Array used to determine the number of hash table buckets to use
5335 based on the number of symbols there are. If there are fewer than
5336 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
5337 fewer than 37 we use 17 buckets, and so forth. We never use more
5338 than 32771 buckets. */
5340 static const size_t elf_buckets[] =
5342 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
5343 16411, 32771, 0
5346 /* Compute bucket count for hashing table. We do not use a static set
5347 of possible tables sizes anymore. Instead we determine for all
5348 possible reasonable sizes of the table the outcome (i.e., the
5349 number of collisions etc) and choose the best solution. The
5350 weighting functions are not too simple to allow the table to grow
5351 without bounds. Instead one of the weighting factors is the size.
5352 Therefore the result is always a good payoff between few collisions
5353 (= short chain lengths) and table size. */
5354 static size_t
5355 compute_bucket_count (struct bfd_link_info *info,
5356 unsigned long int *hashcodes ATTRIBUTE_UNUSED,
5357 unsigned long int nsyms,
5358 int gnu_hash)
5360 size_t best_size = 0;
5361 unsigned long int i;
5363 /* We have a problem here. The following code to optimize the table
5364 size requires an integer type with more the 32 bits. If
5365 BFD_HOST_U_64_BIT is set we know about such a type. */
5366 #ifdef BFD_HOST_U_64_BIT
5367 if (info->optimize)
5369 size_t minsize;
5370 size_t maxsize;
5371 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
5372 bfd *dynobj = elf_hash_table (info)->dynobj;
5373 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
5374 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
5375 unsigned long int *counts;
5376 bfd_size_type amt;
5378 /* Possible optimization parameters: if we have NSYMS symbols we say
5379 that the hashing table must at least have NSYMS/4 and at most
5380 2*NSYMS buckets. */
5381 minsize = nsyms / 4;
5382 if (minsize == 0)
5383 minsize = 1;
5384 best_size = maxsize = nsyms * 2;
5385 if (gnu_hash)
5387 if (minsize < 2)
5388 minsize = 2;
5389 if ((best_size & 31) == 0)
5390 ++best_size;
5393 /* Create array where we count the collisions in. We must use bfd_malloc
5394 since the size could be large. */
5395 amt = maxsize;
5396 amt *= sizeof (unsigned long int);
5397 counts = (unsigned long int *) bfd_malloc (amt);
5398 if (counts == NULL)
5399 return 0;
5401 /* Compute the "optimal" size for the hash table. The criteria is a
5402 minimal chain length. The minor criteria is (of course) the size
5403 of the table. */
5404 for (i = minsize; i < maxsize; ++i)
5406 /* Walk through the array of hashcodes and count the collisions. */
5407 BFD_HOST_U_64_BIT max;
5408 unsigned long int j;
5409 unsigned long int fact;
5411 if (gnu_hash && (i & 31) == 0)
5412 continue;
5414 memset (counts, '\0', i * sizeof (unsigned long int));
5416 /* Determine how often each hash bucket is used. */
5417 for (j = 0; j < nsyms; ++j)
5418 ++counts[hashcodes[j] % i];
5420 /* For the weight function we need some information about the
5421 pagesize on the target. This is information need not be 100%
5422 accurate. Since this information is not available (so far) we
5423 define it here to a reasonable default value. If it is crucial
5424 to have a better value some day simply define this value. */
5425 # ifndef BFD_TARGET_PAGESIZE
5426 # define BFD_TARGET_PAGESIZE (4096)
5427 # endif
5429 /* We in any case need 2 + DYNSYMCOUNT entries for the size values
5430 and the chains. */
5431 max = (2 + dynsymcount) * bed->s->sizeof_hash_entry;
5433 # if 1
5434 /* Variant 1: optimize for short chains. We add the squares
5435 of all the chain lengths (which favors many small chain
5436 over a few long chains). */
5437 for (j = 0; j < i; ++j)
5438 max += counts[j] * counts[j];
5440 /* This adds penalties for the overall size of the table. */
5441 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5442 max *= fact * fact;
5443 # else
5444 /* Variant 2: Optimize a lot more for small table. Here we
5445 also add squares of the size but we also add penalties for
5446 empty slots (the +1 term). */
5447 for (j = 0; j < i; ++j)
5448 max += (1 + counts[j]) * (1 + counts[j]);
5450 /* The overall size of the table is considered, but not as
5451 strong as in variant 1, where it is squared. */
5452 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5453 max *= fact;
5454 # endif
5456 /* Compare with current best results. */
5457 if (max < best_chlen)
5459 best_chlen = max;
5460 best_size = i;
5464 free (counts);
5466 else
5467 #endif /* defined (BFD_HOST_U_64_BIT) */
5469 /* This is the fallback solution if no 64bit type is available or if we
5470 are not supposed to spend much time on optimizations. We select the
5471 bucket count using a fixed set of numbers. */
5472 for (i = 0; elf_buckets[i] != 0; i++)
5474 best_size = elf_buckets[i];
5475 if (nsyms < elf_buckets[i + 1])
5476 break;
5478 if (gnu_hash && best_size < 2)
5479 best_size = 2;
5482 return best_size;
5485 /* Size any SHT_GROUP section for ld -r. */
5487 bfd_boolean
5488 _bfd_elf_size_group_sections (struct bfd_link_info *info)
5490 bfd *ibfd;
5492 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
5493 if (bfd_get_flavour (ibfd) == bfd_target_elf_flavour
5494 && !_bfd_elf_fixup_group_sections (ibfd, bfd_abs_section_ptr))
5495 return FALSE;
5496 return TRUE;
5499 /* Set up the sizes and contents of the ELF dynamic sections. This is
5500 called by the ELF linker emulation before_allocation routine. We
5501 must set the sizes of the sections before the linker sets the
5502 addresses of the various sections. */
5504 bfd_boolean
5505 bfd_elf_size_dynamic_sections (bfd *output_bfd,
5506 const char *soname,
5507 const char *rpath,
5508 const char *filter_shlib,
5509 const char *audit,
5510 const char *depaudit,
5511 const char * const *auxiliary_filters,
5512 struct bfd_link_info *info,
5513 asection **sinterpptr,
5514 struct bfd_elf_version_tree *verdefs)
5516 bfd_size_type soname_indx;
5517 bfd *dynobj;
5518 const struct elf_backend_data *bed;
5519 struct elf_info_failed asvinfo;
5521 *sinterpptr = NULL;
5523 soname_indx = (bfd_size_type) -1;
5525 if (!is_elf_hash_table (info->hash))
5526 return TRUE;
5528 bed = get_elf_backend_data (output_bfd);
5529 if (info->execstack)
5530 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
5531 else if (info->noexecstack)
5532 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
5533 else
5535 bfd *inputobj;
5536 asection *notesec = NULL;
5537 int exec = 0;
5539 for (inputobj = info->input_bfds;
5540 inputobj;
5541 inputobj = inputobj->link_next)
5543 asection *s;
5545 if (inputobj->flags & (DYNAMIC | EXEC_P | BFD_LINKER_CREATED))
5546 continue;
5547 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
5548 if (s)
5550 if (s->flags & SEC_CODE)
5551 exec = PF_X;
5552 notesec = s;
5554 else if (bed->default_execstack)
5555 exec = PF_X;
5557 if (notesec)
5559 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
5560 if (exec && info->relocatable
5561 && notesec->output_section != bfd_abs_section_ptr)
5562 notesec->output_section->flags |= SEC_CODE;
5566 /* Any syms created from now on start with -1 in
5567 got.refcount/offset and plt.refcount/offset. */
5568 elf_hash_table (info)->init_got_refcount
5569 = elf_hash_table (info)->init_got_offset;
5570 elf_hash_table (info)->init_plt_refcount
5571 = elf_hash_table (info)->init_plt_offset;
5573 if (info->relocatable
5574 && !_bfd_elf_size_group_sections (info))
5575 return FALSE;
5577 /* The backend may have to create some sections regardless of whether
5578 we're dynamic or not. */
5579 if (bed->elf_backend_always_size_sections
5580 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
5581 return FALSE;
5583 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5584 return FALSE;
5586 dynobj = elf_hash_table (info)->dynobj;
5588 /* If there were no dynamic objects in the link, there is nothing to
5589 do here. */
5590 if (dynobj == NULL)
5591 return TRUE;
5593 if (elf_hash_table (info)->dynamic_sections_created)
5595 struct elf_info_failed eif;
5596 struct elf_link_hash_entry *h;
5597 asection *dynstr;
5598 struct bfd_elf_version_tree *t;
5599 struct bfd_elf_version_expr *d;
5600 asection *s;
5601 bfd_boolean all_defined;
5603 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5604 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5606 if (soname != NULL)
5608 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5609 soname, TRUE);
5610 if (soname_indx == (bfd_size_type) -1
5611 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5612 return FALSE;
5615 if (info->symbolic)
5617 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5618 return FALSE;
5619 info->flags |= DF_SYMBOLIC;
5622 if (rpath != NULL)
5624 bfd_size_type indx;
5626 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5627 TRUE);
5628 if (indx == (bfd_size_type) -1
5629 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5630 return FALSE;
5632 if (info->new_dtags)
5634 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5635 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5636 return FALSE;
5640 if (filter_shlib != NULL)
5642 bfd_size_type indx;
5644 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5645 filter_shlib, TRUE);
5646 if (indx == (bfd_size_type) -1
5647 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5648 return FALSE;
5651 if (auxiliary_filters != NULL)
5653 const char * const *p;
5655 for (p = auxiliary_filters; *p != NULL; p++)
5657 bfd_size_type indx;
5659 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5660 *p, TRUE);
5661 if (indx == (bfd_size_type) -1
5662 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5663 return FALSE;
5667 if (audit != NULL)
5669 bfd_size_type indx;
5671 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
5672 TRUE);
5673 if (indx == (bfd_size_type) -1
5674 || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
5675 return FALSE;
5678 if (depaudit != NULL)
5680 bfd_size_type indx;
5682 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
5683 TRUE);
5684 if (indx == (bfd_size_type) -1
5685 || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
5686 return FALSE;
5689 eif.info = info;
5690 eif.verdefs = verdefs;
5691 eif.failed = FALSE;
5693 /* If we are supposed to export all symbols into the dynamic symbol
5694 table (this is not the normal case), then do so. */
5695 if (info->export_dynamic
5696 || (info->executable && info->dynamic))
5698 elf_link_hash_traverse (elf_hash_table (info),
5699 _bfd_elf_export_symbol,
5700 &eif);
5701 if (eif.failed)
5702 return FALSE;
5705 /* Make all global versions with definition. */
5706 for (t = verdefs; t != NULL; t = t->next)
5707 for (d = t->globals.list; d != NULL; d = d->next)
5708 if (!d->symver && d->literal)
5710 const char *verstr, *name;
5711 size_t namelen, verlen, newlen;
5712 char *newname, *p;
5713 struct elf_link_hash_entry *newh;
5715 name = d->pattern;
5716 namelen = strlen (name);
5717 verstr = t->name;
5718 verlen = strlen (verstr);
5719 newlen = namelen + verlen + 3;
5721 newname = (char *) bfd_malloc (newlen);
5722 if (newname == NULL)
5723 return FALSE;
5724 memcpy (newname, name, namelen);
5726 /* Check the hidden versioned definition. */
5727 p = newname + namelen;
5728 *p++ = ELF_VER_CHR;
5729 memcpy (p, verstr, verlen + 1);
5730 newh = elf_link_hash_lookup (elf_hash_table (info),
5731 newname, FALSE, FALSE,
5732 FALSE);
5733 if (newh == NULL
5734 || (newh->root.type != bfd_link_hash_defined
5735 && newh->root.type != bfd_link_hash_defweak))
5737 /* Check the default versioned definition. */
5738 *p++ = ELF_VER_CHR;
5739 memcpy (p, verstr, verlen + 1);
5740 newh = elf_link_hash_lookup (elf_hash_table (info),
5741 newname, FALSE, FALSE,
5742 FALSE);
5744 free (newname);
5746 /* Mark this version if there is a definition and it is
5747 not defined in a shared object. */
5748 if (newh != NULL
5749 && !newh->def_dynamic
5750 && (newh->root.type == bfd_link_hash_defined
5751 || newh->root.type == bfd_link_hash_defweak))
5752 d->symver = 1;
5755 /* Attach all the symbols to their version information. */
5756 asvinfo.info = info;
5757 asvinfo.verdefs = verdefs;
5758 asvinfo.failed = FALSE;
5760 elf_link_hash_traverse (elf_hash_table (info),
5761 _bfd_elf_link_assign_sym_version,
5762 &asvinfo);
5763 if (asvinfo.failed)
5764 return FALSE;
5766 if (!info->allow_undefined_version)
5768 /* Check if all global versions have a definition. */
5769 all_defined = TRUE;
5770 for (t = verdefs; t != NULL; t = t->next)
5771 for (d = t->globals.list; d != NULL; d = d->next)
5772 if (d->literal && !d->symver && !d->script)
5774 (*_bfd_error_handler)
5775 (_("%s: undefined version: %s"),
5776 d->pattern, t->name);
5777 all_defined = FALSE;
5780 if (!all_defined)
5782 bfd_set_error (bfd_error_bad_value);
5783 return FALSE;
5787 /* Find all symbols which were defined in a dynamic object and make
5788 the backend pick a reasonable value for them. */
5789 elf_link_hash_traverse (elf_hash_table (info),
5790 _bfd_elf_adjust_dynamic_symbol,
5791 &eif);
5792 if (eif.failed)
5793 return FALSE;
5795 /* Add some entries to the .dynamic section. We fill in some of the
5796 values later, in bfd_elf_final_link, but we must add the entries
5797 now so that we know the final size of the .dynamic section. */
5799 /* If there are initialization and/or finalization functions to
5800 call then add the corresponding DT_INIT/DT_FINI entries. */
5801 h = (info->init_function
5802 ? elf_link_hash_lookup (elf_hash_table (info),
5803 info->init_function, FALSE,
5804 FALSE, FALSE)
5805 : NULL);
5806 if (h != NULL
5807 && (h->ref_regular
5808 || h->def_regular))
5810 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5811 return FALSE;
5813 h = (info->fini_function
5814 ? elf_link_hash_lookup (elf_hash_table (info),
5815 info->fini_function, FALSE,
5816 FALSE, FALSE)
5817 : NULL);
5818 if (h != NULL
5819 && (h->ref_regular
5820 || h->def_regular))
5822 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5823 return FALSE;
5826 s = bfd_get_section_by_name (output_bfd, ".preinit_array");
5827 if (s != NULL && s->linker_has_input)
5829 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5830 if (! info->executable)
5832 bfd *sub;
5833 asection *o;
5835 for (sub = info->input_bfds; sub != NULL;
5836 sub = sub->link_next)
5837 if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
5838 for (o = sub->sections; o != NULL; o = o->next)
5839 if (elf_section_data (o)->this_hdr.sh_type
5840 == SHT_PREINIT_ARRAY)
5842 (*_bfd_error_handler)
5843 (_("%B: .preinit_array section is not allowed in DSO"),
5844 sub);
5845 break;
5848 bfd_set_error (bfd_error_nonrepresentable_section);
5849 return FALSE;
5852 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5853 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5854 return FALSE;
5856 s = bfd_get_section_by_name (output_bfd, ".init_array");
5857 if (s != NULL && s->linker_has_input)
5859 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5860 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5861 return FALSE;
5863 s = bfd_get_section_by_name (output_bfd, ".fini_array");
5864 if (s != NULL && s->linker_has_input)
5866 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5867 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5868 return FALSE;
5871 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5872 /* If .dynstr is excluded from the link, we don't want any of
5873 these tags. Strictly, we should be checking each section
5874 individually; This quick check covers for the case where
5875 someone does a /DISCARD/ : { *(*) }. */
5876 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5878 bfd_size_type strsize;
5880 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5881 if ((info->emit_hash
5882 && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
5883 || (info->emit_gnu_hash
5884 && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0))
5885 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5886 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5887 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5888 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5889 bed->s->sizeof_sym))
5890 return FALSE;
5894 /* The backend must work out the sizes of all the other dynamic
5895 sections. */
5896 if (bed->elf_backend_size_dynamic_sections
5897 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5898 return FALSE;
5900 if (elf_hash_table (info)->dynamic_sections_created)
5902 unsigned long section_sym_count;
5903 asection *s;
5905 /* Set up the version definition section. */
5906 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5907 BFD_ASSERT (s != NULL);
5909 /* We may have created additional version definitions if we are
5910 just linking a regular application. */
5911 verdefs = asvinfo.verdefs;
5913 /* Skip anonymous version tag. */
5914 if (verdefs != NULL && verdefs->vernum == 0)
5915 verdefs = verdefs->next;
5917 if (verdefs == NULL && !info->create_default_symver)
5918 s->flags |= SEC_EXCLUDE;
5919 else
5921 unsigned int cdefs;
5922 bfd_size_type size;
5923 struct bfd_elf_version_tree *t;
5924 bfd_byte *p;
5925 Elf_Internal_Verdef def;
5926 Elf_Internal_Verdaux defaux;
5927 struct bfd_link_hash_entry *bh;
5928 struct elf_link_hash_entry *h;
5929 const char *name;
5931 cdefs = 0;
5932 size = 0;
5934 /* Make space for the base version. */
5935 size += sizeof (Elf_External_Verdef);
5936 size += sizeof (Elf_External_Verdaux);
5937 ++cdefs;
5939 /* Make space for the default version. */
5940 if (info->create_default_symver)
5942 size += sizeof (Elf_External_Verdef);
5943 ++cdefs;
5946 for (t = verdefs; t != NULL; t = t->next)
5948 struct bfd_elf_version_deps *n;
5950 /* Don't emit base version twice. */
5951 if (t->vernum == 0)
5952 continue;
5954 size += sizeof (Elf_External_Verdef);
5955 size += sizeof (Elf_External_Verdaux);
5956 ++cdefs;
5958 for (n = t->deps; n != NULL; n = n->next)
5959 size += sizeof (Elf_External_Verdaux);
5962 s->size = size;
5963 s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
5964 if (s->contents == NULL && s->size != 0)
5965 return FALSE;
5967 /* Fill in the version definition section. */
5969 p = s->contents;
5971 def.vd_version = VER_DEF_CURRENT;
5972 def.vd_flags = VER_FLG_BASE;
5973 def.vd_ndx = 1;
5974 def.vd_cnt = 1;
5975 if (info->create_default_symver)
5977 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5978 def.vd_next = sizeof (Elf_External_Verdef);
5980 else
5982 def.vd_aux = sizeof (Elf_External_Verdef);
5983 def.vd_next = (sizeof (Elf_External_Verdef)
5984 + sizeof (Elf_External_Verdaux));
5987 if (soname_indx != (bfd_size_type) -1)
5989 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5990 soname_indx);
5991 def.vd_hash = bfd_elf_hash (soname);
5992 defaux.vda_name = soname_indx;
5993 name = soname;
5995 else
5997 bfd_size_type indx;
5999 name = lbasename (output_bfd->filename);
6000 def.vd_hash = bfd_elf_hash (name);
6001 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6002 name, FALSE);
6003 if (indx == (bfd_size_type) -1)
6004 return FALSE;
6005 defaux.vda_name = indx;
6007 defaux.vda_next = 0;
6009 _bfd_elf_swap_verdef_out (output_bfd, &def,
6010 (Elf_External_Verdef *) p);
6011 p += sizeof (Elf_External_Verdef);
6012 if (info->create_default_symver)
6014 /* Add a symbol representing this version. */
6015 bh = NULL;
6016 if (! (_bfd_generic_link_add_one_symbol
6017 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
6018 0, NULL, FALSE,
6019 get_elf_backend_data (dynobj)->collect, &bh)))
6020 return FALSE;
6021 h = (struct elf_link_hash_entry *) bh;
6022 h->non_elf = 0;
6023 h->def_regular = 1;
6024 h->type = STT_OBJECT;
6025 h->verinfo.vertree = NULL;
6027 if (! bfd_elf_link_record_dynamic_symbol (info, h))
6028 return FALSE;
6030 /* Create a duplicate of the base version with the same
6031 aux block, but different flags. */
6032 def.vd_flags = 0;
6033 def.vd_ndx = 2;
6034 def.vd_aux = sizeof (Elf_External_Verdef);
6035 if (verdefs)
6036 def.vd_next = (sizeof (Elf_External_Verdef)
6037 + sizeof (Elf_External_Verdaux));
6038 else
6039 def.vd_next = 0;
6040 _bfd_elf_swap_verdef_out (output_bfd, &def,
6041 (Elf_External_Verdef *) p);
6042 p += sizeof (Elf_External_Verdef);
6044 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6045 (Elf_External_Verdaux *) p);
6046 p += sizeof (Elf_External_Verdaux);
6048 for (t = verdefs; t != NULL; t = t->next)
6050 unsigned int cdeps;
6051 struct bfd_elf_version_deps *n;
6053 /* Don't emit the base version twice. */
6054 if (t->vernum == 0)
6055 continue;
6057 cdeps = 0;
6058 for (n = t->deps; n != NULL; n = n->next)
6059 ++cdeps;
6061 /* Add a symbol representing this version. */
6062 bh = NULL;
6063 if (! (_bfd_generic_link_add_one_symbol
6064 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
6065 0, NULL, FALSE,
6066 get_elf_backend_data (dynobj)->collect, &bh)))
6067 return FALSE;
6068 h = (struct elf_link_hash_entry *) bh;
6069 h->non_elf = 0;
6070 h->def_regular = 1;
6071 h->type = STT_OBJECT;
6072 h->verinfo.vertree = t;
6074 if (! bfd_elf_link_record_dynamic_symbol (info, h))
6075 return FALSE;
6077 def.vd_version = VER_DEF_CURRENT;
6078 def.vd_flags = 0;
6079 if (t->globals.list == NULL
6080 && t->locals.list == NULL
6081 && ! t->used)
6082 def.vd_flags |= VER_FLG_WEAK;
6083 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
6084 def.vd_cnt = cdeps + 1;
6085 def.vd_hash = bfd_elf_hash (t->name);
6086 def.vd_aux = sizeof (Elf_External_Verdef);
6087 def.vd_next = 0;
6089 /* If a basever node is next, it *must* be the last node in
6090 the chain, otherwise Verdef construction breaks. */
6091 if (t->next != NULL && t->next->vernum == 0)
6092 BFD_ASSERT (t->next->next == NULL);
6094 if (t->next != NULL && t->next->vernum != 0)
6095 def.vd_next = (sizeof (Elf_External_Verdef)
6096 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
6098 _bfd_elf_swap_verdef_out (output_bfd, &def,
6099 (Elf_External_Verdef *) p);
6100 p += sizeof (Elf_External_Verdef);
6102 defaux.vda_name = h->dynstr_index;
6103 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6104 h->dynstr_index);
6105 defaux.vda_next = 0;
6106 if (t->deps != NULL)
6107 defaux.vda_next = sizeof (Elf_External_Verdaux);
6108 t->name_indx = defaux.vda_name;
6110 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6111 (Elf_External_Verdaux *) p);
6112 p += sizeof (Elf_External_Verdaux);
6114 for (n = t->deps; n != NULL; n = n->next)
6116 if (n->version_needed == NULL)
6118 /* This can happen if there was an error in the
6119 version script. */
6120 defaux.vda_name = 0;
6122 else
6124 defaux.vda_name = n->version_needed->name_indx;
6125 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6126 defaux.vda_name);
6128 if (n->next == NULL)
6129 defaux.vda_next = 0;
6130 else
6131 defaux.vda_next = sizeof (Elf_External_Verdaux);
6133 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6134 (Elf_External_Verdaux *) p);
6135 p += sizeof (Elf_External_Verdaux);
6139 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
6140 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
6141 return FALSE;
6143 elf_tdata (output_bfd)->cverdefs = cdefs;
6146 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
6148 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
6149 return FALSE;
6151 else if (info->flags & DF_BIND_NOW)
6153 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
6154 return FALSE;
6157 if (info->flags_1)
6159 if (info->executable)
6160 info->flags_1 &= ~ (DF_1_INITFIRST
6161 | DF_1_NODELETE
6162 | DF_1_NOOPEN);
6163 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
6164 return FALSE;
6167 /* Work out the size of the version reference section. */
6169 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
6170 BFD_ASSERT (s != NULL);
6172 struct elf_find_verdep_info sinfo;
6174 sinfo.info = info;
6175 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
6176 if (sinfo.vers == 0)
6177 sinfo.vers = 1;
6178 sinfo.failed = FALSE;
6180 elf_link_hash_traverse (elf_hash_table (info),
6181 _bfd_elf_link_find_version_dependencies,
6182 &sinfo);
6183 if (sinfo.failed)
6184 return FALSE;
6186 if (elf_tdata (output_bfd)->verref == NULL)
6187 s->flags |= SEC_EXCLUDE;
6188 else
6190 Elf_Internal_Verneed *t;
6191 unsigned int size;
6192 unsigned int crefs;
6193 bfd_byte *p;
6195 /* Build the version dependency section. */
6196 size = 0;
6197 crefs = 0;
6198 for (t = elf_tdata (output_bfd)->verref;
6199 t != NULL;
6200 t = t->vn_nextref)
6202 Elf_Internal_Vernaux *a;
6204 size += sizeof (Elf_External_Verneed);
6205 ++crefs;
6206 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6207 size += sizeof (Elf_External_Vernaux);
6210 s->size = size;
6211 s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
6212 if (s->contents == NULL)
6213 return FALSE;
6215 p = s->contents;
6216 for (t = elf_tdata (output_bfd)->verref;
6217 t != NULL;
6218 t = t->vn_nextref)
6220 unsigned int caux;
6221 Elf_Internal_Vernaux *a;
6222 bfd_size_type indx;
6224 caux = 0;
6225 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6226 ++caux;
6228 t->vn_version = VER_NEED_CURRENT;
6229 t->vn_cnt = caux;
6230 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6231 elf_dt_name (t->vn_bfd) != NULL
6232 ? elf_dt_name (t->vn_bfd)
6233 : lbasename (t->vn_bfd->filename),
6234 FALSE);
6235 if (indx == (bfd_size_type) -1)
6236 return FALSE;
6237 t->vn_file = indx;
6238 t->vn_aux = sizeof (Elf_External_Verneed);
6239 if (t->vn_nextref == NULL)
6240 t->vn_next = 0;
6241 else
6242 t->vn_next = (sizeof (Elf_External_Verneed)
6243 + caux * sizeof (Elf_External_Vernaux));
6245 _bfd_elf_swap_verneed_out (output_bfd, t,
6246 (Elf_External_Verneed *) p);
6247 p += sizeof (Elf_External_Verneed);
6249 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6251 a->vna_hash = bfd_elf_hash (a->vna_nodename);
6252 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6253 a->vna_nodename, FALSE);
6254 if (indx == (bfd_size_type) -1)
6255 return FALSE;
6256 a->vna_name = indx;
6257 if (a->vna_nextptr == NULL)
6258 a->vna_next = 0;
6259 else
6260 a->vna_next = sizeof (Elf_External_Vernaux);
6262 _bfd_elf_swap_vernaux_out (output_bfd, a,
6263 (Elf_External_Vernaux *) p);
6264 p += sizeof (Elf_External_Vernaux);
6268 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
6269 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
6270 return FALSE;
6272 elf_tdata (output_bfd)->cverrefs = crefs;
6276 if ((elf_tdata (output_bfd)->cverrefs == 0
6277 && elf_tdata (output_bfd)->cverdefs == 0)
6278 || _bfd_elf_link_renumber_dynsyms (output_bfd, info,
6279 &section_sym_count) == 0)
6281 s = bfd_get_section_by_name (dynobj, ".gnu.version");
6282 s->flags |= SEC_EXCLUDE;
6285 return TRUE;
6288 /* Find the first non-excluded output section. We'll use its
6289 section symbol for some emitted relocs. */
6290 void
6291 _bfd_elf_init_1_index_section (bfd *output_bfd, struct bfd_link_info *info)
6293 asection *s;
6295 for (s = output_bfd->sections; s != NULL; s = s->next)
6296 if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
6297 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6299 elf_hash_table (info)->text_index_section = s;
6300 break;
6304 /* Find two non-excluded output sections, one for code, one for data.
6305 We'll use their section symbols for some emitted relocs. */
6306 void
6307 _bfd_elf_init_2_index_sections (bfd *output_bfd, struct bfd_link_info *info)
6309 asection *s;
6311 /* Data first, since setting text_index_section changes
6312 _bfd_elf_link_omit_section_dynsym. */
6313 for (s = output_bfd->sections; s != NULL; s = s->next)
6314 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY)) == SEC_ALLOC)
6315 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6317 elf_hash_table (info)->data_index_section = s;
6318 break;
6321 for (s = output_bfd->sections; s != NULL; s = s->next)
6322 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY))
6323 == (SEC_ALLOC | SEC_READONLY))
6324 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6326 elf_hash_table (info)->text_index_section = s;
6327 break;
6330 if (elf_hash_table (info)->text_index_section == NULL)
6331 elf_hash_table (info)->text_index_section
6332 = elf_hash_table (info)->data_index_section;
6335 bfd_boolean
6336 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
6338 const struct elf_backend_data *bed;
6340 if (!is_elf_hash_table (info->hash))
6341 return TRUE;
6343 bed = get_elf_backend_data (output_bfd);
6344 (*bed->elf_backend_init_index_section) (output_bfd, info);
6346 if (elf_hash_table (info)->dynamic_sections_created)
6348 bfd *dynobj;
6349 asection *s;
6350 bfd_size_type dynsymcount;
6351 unsigned long section_sym_count;
6352 unsigned int dtagcount;
6354 dynobj = elf_hash_table (info)->dynobj;
6356 /* Assign dynsym indicies. In a shared library we generate a
6357 section symbol for each output section, which come first.
6358 Next come all of the back-end allocated local dynamic syms,
6359 followed by the rest of the global symbols. */
6361 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
6362 &section_sym_count);
6364 /* Work out the size of the symbol version section. */
6365 s = bfd_get_section_by_name (dynobj, ".gnu.version");
6366 BFD_ASSERT (s != NULL);
6367 if (dynsymcount != 0
6368 && (s->flags & SEC_EXCLUDE) == 0)
6370 s->size = dynsymcount * sizeof (Elf_External_Versym);
6371 s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
6372 if (s->contents == NULL)
6373 return FALSE;
6375 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
6376 return FALSE;
6379 /* Set the size of the .dynsym and .hash sections. We counted
6380 the number of dynamic symbols in elf_link_add_object_symbols.
6381 We will build the contents of .dynsym and .hash when we build
6382 the final symbol table, because until then we do not know the
6383 correct value to give the symbols. We built the .dynstr
6384 section as we went along in elf_link_add_object_symbols. */
6385 s = bfd_get_section_by_name (dynobj, ".dynsym");
6386 BFD_ASSERT (s != NULL);
6387 s->size = dynsymcount * bed->s->sizeof_sym;
6389 if (dynsymcount != 0)
6391 s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
6392 if (s->contents == NULL)
6393 return FALSE;
6395 /* The first entry in .dynsym is a dummy symbol.
6396 Clear all the section syms, in case we don't output them all. */
6397 ++section_sym_count;
6398 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
6401 elf_hash_table (info)->bucketcount = 0;
6403 /* Compute the size of the hashing table. As a side effect this
6404 computes the hash values for all the names we export. */
6405 if (info->emit_hash)
6407 unsigned long int *hashcodes;
6408 struct hash_codes_info hashinf;
6409 bfd_size_type amt;
6410 unsigned long int nsyms;
6411 size_t bucketcount;
6412 size_t hash_entry_size;
6414 /* Compute the hash values for all exported symbols. At the same
6415 time store the values in an array so that we could use them for
6416 optimizations. */
6417 amt = dynsymcount * sizeof (unsigned long int);
6418 hashcodes = (unsigned long int *) bfd_malloc (amt);
6419 if (hashcodes == NULL)
6420 return FALSE;
6421 hashinf.hashcodes = hashcodes;
6422 hashinf.error = FALSE;
6424 /* Put all hash values in HASHCODES. */
6425 elf_link_hash_traverse (elf_hash_table (info),
6426 elf_collect_hash_codes, &hashinf);
6427 if (hashinf.error)
6429 free (hashcodes);
6430 return FALSE;
6433 nsyms = hashinf.hashcodes - hashcodes;
6434 bucketcount
6435 = compute_bucket_count (info, hashcodes, nsyms, 0);
6436 free (hashcodes);
6438 if (bucketcount == 0)
6439 return FALSE;
6441 elf_hash_table (info)->bucketcount = bucketcount;
6443 s = bfd_get_section_by_name (dynobj, ".hash");
6444 BFD_ASSERT (s != NULL);
6445 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
6446 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
6447 s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
6448 if (s->contents == NULL)
6449 return FALSE;
6451 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
6452 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
6453 s->contents + hash_entry_size);
6456 if (info->emit_gnu_hash)
6458 size_t i, cnt;
6459 unsigned char *contents;
6460 struct collect_gnu_hash_codes cinfo;
6461 bfd_size_type amt;
6462 size_t bucketcount;
6464 memset (&cinfo, 0, sizeof (cinfo));
6466 /* Compute the hash values for all exported symbols. At the same
6467 time store the values in an array so that we could use them for
6468 optimizations. */
6469 amt = dynsymcount * 2 * sizeof (unsigned long int);
6470 cinfo.hashcodes = (long unsigned int *) bfd_malloc (amt);
6471 if (cinfo.hashcodes == NULL)
6472 return FALSE;
6474 cinfo.hashval = cinfo.hashcodes + dynsymcount;
6475 cinfo.min_dynindx = -1;
6476 cinfo.output_bfd = output_bfd;
6477 cinfo.bed = bed;
6479 /* Put all hash values in HASHCODES. */
6480 elf_link_hash_traverse (elf_hash_table (info),
6481 elf_collect_gnu_hash_codes, &cinfo);
6482 if (cinfo.error)
6484 free (cinfo.hashcodes);
6485 return FALSE;
6488 bucketcount
6489 = compute_bucket_count (info, cinfo.hashcodes, cinfo.nsyms, 1);
6491 if (bucketcount == 0)
6493 free (cinfo.hashcodes);
6494 return FALSE;
6497 s = bfd_get_section_by_name (dynobj, ".gnu.hash");
6498 BFD_ASSERT (s != NULL);
6500 if (cinfo.nsyms == 0)
6502 /* Empty .gnu.hash section is special. */
6503 BFD_ASSERT (cinfo.min_dynindx == -1);
6504 free (cinfo.hashcodes);
6505 s->size = 5 * 4 + bed->s->arch_size / 8;
6506 contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
6507 if (contents == NULL)
6508 return FALSE;
6509 s->contents = contents;
6510 /* 1 empty bucket. */
6511 bfd_put_32 (output_bfd, 1, contents);
6512 /* SYMIDX above the special symbol 0. */
6513 bfd_put_32 (output_bfd, 1, contents + 4);
6514 /* Just one word for bitmask. */
6515 bfd_put_32 (output_bfd, 1, contents + 8);
6516 /* Only hash fn bloom filter. */
6517 bfd_put_32 (output_bfd, 0, contents + 12);
6518 /* No hashes are valid - empty bitmask. */
6519 bfd_put (bed->s->arch_size, output_bfd, 0, contents + 16);
6520 /* No hashes in the only bucket. */
6521 bfd_put_32 (output_bfd, 0,
6522 contents + 16 + bed->s->arch_size / 8);
6524 else
6526 unsigned long int maskwords, maskbitslog2;
6527 BFD_ASSERT (cinfo.min_dynindx != -1);
6529 maskbitslog2 = bfd_log2 (cinfo.nsyms) + 1;
6530 if (maskbitslog2 < 3)
6531 maskbitslog2 = 5;
6532 else if ((1 << (maskbitslog2 - 2)) & cinfo.nsyms)
6533 maskbitslog2 = maskbitslog2 + 3;
6534 else
6535 maskbitslog2 = maskbitslog2 + 2;
6536 if (bed->s->arch_size == 64)
6538 if (maskbitslog2 == 5)
6539 maskbitslog2 = 6;
6540 cinfo.shift1 = 6;
6542 else
6543 cinfo.shift1 = 5;
6544 cinfo.mask = (1 << cinfo.shift1) - 1;
6545 cinfo.shift2 = maskbitslog2;
6546 cinfo.maskbits = 1 << maskbitslog2;
6547 maskwords = 1 << (maskbitslog2 - cinfo.shift1);
6548 amt = bucketcount * sizeof (unsigned long int) * 2;
6549 amt += maskwords * sizeof (bfd_vma);
6550 cinfo.bitmask = (bfd_vma *) bfd_malloc (amt);
6551 if (cinfo.bitmask == NULL)
6553 free (cinfo.hashcodes);
6554 return FALSE;
6557 cinfo.counts = (long unsigned int *) (cinfo.bitmask + maskwords);
6558 cinfo.indx = cinfo.counts + bucketcount;
6559 cinfo.symindx = dynsymcount - cinfo.nsyms;
6560 memset (cinfo.bitmask, 0, maskwords * sizeof (bfd_vma));
6562 /* Determine how often each hash bucket is used. */
6563 memset (cinfo.counts, 0, bucketcount * sizeof (cinfo.counts[0]));
6564 for (i = 0; i < cinfo.nsyms; ++i)
6565 ++cinfo.counts[cinfo.hashcodes[i] % bucketcount];
6567 for (i = 0, cnt = cinfo.symindx; i < bucketcount; ++i)
6568 if (cinfo.counts[i] != 0)
6570 cinfo.indx[i] = cnt;
6571 cnt += cinfo.counts[i];
6573 BFD_ASSERT (cnt == dynsymcount);
6574 cinfo.bucketcount = bucketcount;
6575 cinfo.local_indx = cinfo.min_dynindx;
6577 s->size = (4 + bucketcount + cinfo.nsyms) * 4;
6578 s->size += cinfo.maskbits / 8;
6579 contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
6580 if (contents == NULL)
6582 free (cinfo.bitmask);
6583 free (cinfo.hashcodes);
6584 return FALSE;
6587 s->contents = contents;
6588 bfd_put_32 (output_bfd, bucketcount, contents);
6589 bfd_put_32 (output_bfd, cinfo.symindx, contents + 4);
6590 bfd_put_32 (output_bfd, maskwords, contents + 8);
6591 bfd_put_32 (output_bfd, cinfo.shift2, contents + 12);
6592 contents += 16 + cinfo.maskbits / 8;
6594 for (i = 0; i < bucketcount; ++i)
6596 if (cinfo.counts[i] == 0)
6597 bfd_put_32 (output_bfd, 0, contents);
6598 else
6599 bfd_put_32 (output_bfd, cinfo.indx[i], contents);
6600 contents += 4;
6603 cinfo.contents = contents;
6605 /* Renumber dynamic symbols, populate .gnu.hash section. */
6606 elf_link_hash_traverse (elf_hash_table (info),
6607 elf_renumber_gnu_hash_syms, &cinfo);
6609 contents = s->contents + 16;
6610 for (i = 0; i < maskwords; ++i)
6612 bfd_put (bed->s->arch_size, output_bfd, cinfo.bitmask[i],
6613 contents);
6614 contents += bed->s->arch_size / 8;
6617 free (cinfo.bitmask);
6618 free (cinfo.hashcodes);
6622 s = bfd_get_section_by_name (dynobj, ".dynstr");
6623 BFD_ASSERT (s != NULL);
6625 elf_finalize_dynstr (output_bfd, info);
6627 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
6629 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
6630 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
6631 return FALSE;
6634 return TRUE;
6637 /* Indicate that we are only retrieving symbol values from this
6638 section. */
6640 void
6641 _bfd_elf_link_just_syms (asection *sec, struct bfd_link_info *info)
6643 if (is_elf_hash_table (info->hash))
6644 sec->sec_info_type = ELF_INFO_TYPE_JUST_SYMS;
6645 _bfd_generic_link_just_syms (sec, info);
6648 /* Make sure sec_info_type is cleared if sec_info is cleared too. */
6650 static void
6651 merge_sections_remove_hook (bfd *abfd ATTRIBUTE_UNUSED,
6652 asection *sec)
6654 BFD_ASSERT (sec->sec_info_type == ELF_INFO_TYPE_MERGE);
6655 sec->sec_info_type = ELF_INFO_TYPE_NONE;
6658 /* Finish SHF_MERGE section merging. */
6660 bfd_boolean
6661 _bfd_elf_merge_sections (bfd *abfd, struct bfd_link_info *info)
6663 bfd *ibfd;
6664 asection *sec;
6666 if (!is_elf_hash_table (info->hash))
6667 return FALSE;
6669 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
6670 if ((ibfd->flags & DYNAMIC) == 0)
6671 for (sec = ibfd->sections; sec != NULL; sec = sec->next)
6672 if ((sec->flags & SEC_MERGE) != 0
6673 && !bfd_is_abs_section (sec->output_section))
6675 struct bfd_elf_section_data *secdata;
6677 secdata = elf_section_data (sec);
6678 if (! _bfd_add_merge_section (abfd,
6679 &elf_hash_table (info)->merge_info,
6680 sec, &secdata->sec_info))
6681 return FALSE;
6682 else if (secdata->sec_info)
6683 sec->sec_info_type = ELF_INFO_TYPE_MERGE;
6686 if (elf_hash_table (info)->merge_info != NULL)
6687 _bfd_merge_sections (abfd, info, elf_hash_table (info)->merge_info,
6688 merge_sections_remove_hook);
6689 return TRUE;
6692 /* Create an entry in an ELF linker hash table. */
6694 struct bfd_hash_entry *
6695 _bfd_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
6696 struct bfd_hash_table *table,
6697 const char *string)
6699 /* Allocate the structure if it has not already been allocated by a
6700 subclass. */
6701 if (entry == NULL)
6703 entry = (struct bfd_hash_entry *)
6704 bfd_hash_allocate (table, sizeof (struct elf_link_hash_entry));
6705 if (entry == NULL)
6706 return entry;
6709 /* Call the allocation method of the superclass. */
6710 entry = _bfd_link_hash_newfunc (entry, table, string);
6711 if (entry != NULL)
6713 struct elf_link_hash_entry *ret = (struct elf_link_hash_entry *) entry;
6714 struct elf_link_hash_table *htab = (struct elf_link_hash_table *) table;
6716 /* Set local fields. */
6717 ret->indx = -1;
6718 ret->dynindx = -1;
6719 ret->got = htab->init_got_refcount;
6720 ret->plt = htab->init_plt_refcount;
6721 memset (&ret->size, 0, (sizeof (struct elf_link_hash_entry)
6722 - offsetof (struct elf_link_hash_entry, size)));
6723 /* Assume that we have been called by a non-ELF symbol reader.
6724 This flag is then reset by the code which reads an ELF input
6725 file. This ensures that a symbol created by a non-ELF symbol
6726 reader will have the flag set correctly. */
6727 ret->non_elf = 1;
6730 return entry;
6733 /* Copy data from an indirect symbol to its direct symbol, hiding the
6734 old indirect symbol. Also used for copying flags to a weakdef. */
6736 void
6737 _bfd_elf_link_hash_copy_indirect (struct bfd_link_info *info,
6738 struct elf_link_hash_entry *dir,
6739 struct elf_link_hash_entry *ind)
6741 struct elf_link_hash_table *htab;
6743 /* Copy down any references that we may have already seen to the
6744 symbol which just became indirect. */
6746 dir->ref_dynamic |= ind->ref_dynamic;
6747 dir->ref_regular |= ind->ref_regular;
6748 dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
6749 dir->non_got_ref |= ind->non_got_ref;
6750 dir->needs_plt |= ind->needs_plt;
6751 dir->pointer_equality_needed |= ind->pointer_equality_needed;
6753 if (ind->root.type != bfd_link_hash_indirect)
6754 return;
6756 /* Copy over the global and procedure linkage table refcount entries.
6757 These may have been already set up by a check_relocs routine. */
6758 htab = elf_hash_table (info);
6759 if (ind->got.refcount > htab->init_got_refcount.refcount)
6761 if (dir->got.refcount < 0)
6762 dir->got.refcount = 0;
6763 dir->got.refcount += ind->got.refcount;
6764 ind->got.refcount = htab->init_got_refcount.refcount;
6767 if (ind->plt.refcount > htab->init_plt_refcount.refcount)
6769 if (dir->plt.refcount < 0)
6770 dir->plt.refcount = 0;
6771 dir->plt.refcount += ind->plt.refcount;
6772 ind->plt.refcount = htab->init_plt_refcount.refcount;
6775 if (ind->dynindx != -1)
6777 if (dir->dynindx != -1)
6778 _bfd_elf_strtab_delref (htab->dynstr, dir->dynstr_index);
6779 dir->dynindx = ind->dynindx;
6780 dir->dynstr_index = ind->dynstr_index;
6781 ind->dynindx = -1;
6782 ind->dynstr_index = 0;
6786 void
6787 _bfd_elf_link_hash_hide_symbol (struct bfd_link_info *info,
6788 struct elf_link_hash_entry *h,
6789 bfd_boolean force_local)
6791 /* STT_GNU_IFUNC symbol must go through PLT. */
6792 if (h->type != STT_GNU_IFUNC)
6794 h->plt = elf_hash_table (info)->init_plt_offset;
6795 h->needs_plt = 0;
6797 if (force_local)
6799 h->forced_local = 1;
6800 if (h->dynindx != -1)
6802 h->dynindx = -1;
6803 _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
6804 h->dynstr_index);
6809 /* Initialize an ELF linker hash table. */
6811 bfd_boolean
6812 _bfd_elf_link_hash_table_init
6813 (struct elf_link_hash_table *table,
6814 bfd *abfd,
6815 struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
6816 struct bfd_hash_table *,
6817 const char *),
6818 unsigned int entsize,
6819 enum elf_target_id target_id)
6821 bfd_boolean ret;
6822 int can_refcount = get_elf_backend_data (abfd)->can_refcount;
6824 memset (table, 0, sizeof * table);
6825 table->init_got_refcount.refcount = can_refcount - 1;
6826 table->init_plt_refcount.refcount = can_refcount - 1;
6827 table->init_got_offset.offset = -(bfd_vma) 1;
6828 table->init_plt_offset.offset = -(bfd_vma) 1;
6829 /* The first dynamic symbol is a dummy. */
6830 table->dynsymcount = 1;
6832 ret = _bfd_link_hash_table_init (&table->root, abfd, newfunc, entsize);
6834 table->root.type = bfd_link_elf_hash_table;
6835 table->hash_table_id = target_id;
6837 return ret;
6840 /* Create an ELF linker hash table. */
6842 struct bfd_link_hash_table *
6843 _bfd_elf_link_hash_table_create (bfd *abfd)
6845 struct elf_link_hash_table *ret;
6846 bfd_size_type amt = sizeof (struct elf_link_hash_table);
6848 ret = (struct elf_link_hash_table *) bfd_malloc (amt);
6849 if (ret == NULL)
6850 return NULL;
6852 if (! _bfd_elf_link_hash_table_init (ret, abfd, _bfd_elf_link_hash_newfunc,
6853 sizeof (struct elf_link_hash_entry),
6854 GENERIC_ELF_DATA))
6856 free (ret);
6857 return NULL;
6860 return &ret->root;
6863 /* This is a hook for the ELF emulation code in the generic linker to
6864 tell the backend linker what file name to use for the DT_NEEDED
6865 entry for a dynamic object. */
6867 void
6868 bfd_elf_set_dt_needed_name (bfd *abfd, const char *name)
6870 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
6871 && bfd_get_format (abfd) == bfd_object)
6872 elf_dt_name (abfd) = name;
6876 bfd_elf_get_dyn_lib_class (bfd *abfd)
6878 int lib_class;
6879 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
6880 && bfd_get_format (abfd) == bfd_object)
6881 lib_class = elf_dyn_lib_class (abfd);
6882 else
6883 lib_class = 0;
6884 return lib_class;
6887 void
6888 bfd_elf_set_dyn_lib_class (bfd *abfd, enum dynamic_lib_link_class lib_class)
6890 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
6891 && bfd_get_format (abfd) == bfd_object)
6892 elf_dyn_lib_class (abfd) = lib_class;
6895 /* Get the list of DT_NEEDED entries for a link. This is a hook for
6896 the linker ELF emulation code. */
6898 struct bfd_link_needed_list *
6899 bfd_elf_get_needed_list (bfd *abfd ATTRIBUTE_UNUSED,
6900 struct bfd_link_info *info)
6902 if (! is_elf_hash_table (info->hash))
6903 return NULL;
6904 return elf_hash_table (info)->needed;
6907 /* Get the list of DT_RPATH/DT_RUNPATH entries for a link. This is a
6908 hook for the linker ELF emulation code. */
6910 struct bfd_link_needed_list *
6911 bfd_elf_get_runpath_list (bfd *abfd ATTRIBUTE_UNUSED,
6912 struct bfd_link_info *info)
6914 if (! is_elf_hash_table (info->hash))
6915 return NULL;
6916 return elf_hash_table (info)->runpath;
6919 /* Get the name actually used for a dynamic object for a link. This
6920 is the SONAME entry if there is one. Otherwise, it is the string
6921 passed to bfd_elf_set_dt_needed_name, or it is the filename. */
6923 const char *
6924 bfd_elf_get_dt_soname (bfd *abfd)
6926 if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
6927 && bfd_get_format (abfd) == bfd_object)
6928 return elf_dt_name (abfd);
6929 return NULL;
6932 /* Get the list of DT_NEEDED entries from a BFD. This is a hook for
6933 the ELF linker emulation code. */
6935 bfd_boolean
6936 bfd_elf_get_bfd_needed_list (bfd *abfd,
6937 struct bfd_link_needed_list **pneeded)
6939 asection *s;
6940 bfd_byte *dynbuf = NULL;
6941 unsigned int elfsec;
6942 unsigned long shlink;
6943 bfd_byte *extdyn, *extdynend;
6944 size_t extdynsize;
6945 void (*swap_dyn_in) (bfd *, const void *, Elf_Internal_Dyn *);
6947 *pneeded = NULL;
6949 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour
6950 || bfd_get_format (abfd) != bfd_object)
6951 return TRUE;
6953 s = bfd_get_section_by_name (abfd, ".dynamic");
6954 if (s == NULL || s->size == 0)
6955 return TRUE;
6957 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
6958 goto error_return;
6960 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
6961 if (elfsec == SHN_BAD)
6962 goto error_return;
6964 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
6966 extdynsize = get_elf_backend_data (abfd)->s->sizeof_dyn;
6967 swap_dyn_in = get_elf_backend_data (abfd)->s->swap_dyn_in;
6969 extdyn = dynbuf;
6970 extdynend = extdyn + s->size;
6971 for (; extdyn < extdynend; extdyn += extdynsize)
6973 Elf_Internal_Dyn dyn;
6975 (*swap_dyn_in) (abfd, extdyn, &dyn);
6977 if (dyn.d_tag == DT_NULL)
6978 break;
6980 if (dyn.d_tag == DT_NEEDED)
6982 const char *string;
6983 struct bfd_link_needed_list *l;
6984 unsigned int tagv = dyn.d_un.d_val;
6985 bfd_size_type amt;
6987 string = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
6988 if (string == NULL)
6989 goto error_return;
6991 amt = sizeof *l;
6992 l = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
6993 if (l == NULL)
6994 goto error_return;
6996 l->by = abfd;
6997 l->name = string;
6998 l->next = *pneeded;
6999 *pneeded = l;
7003 free (dynbuf);
7005 return TRUE;
7007 error_return:
7008 if (dynbuf != NULL)
7009 free (dynbuf);
7010 return FALSE;
7013 struct elf_symbuf_symbol
7015 unsigned long st_name; /* Symbol name, index in string tbl */
7016 unsigned char st_info; /* Type and binding attributes */
7017 unsigned char st_other; /* Visibilty, and target specific */
7020 struct elf_symbuf_head
7022 struct elf_symbuf_symbol *ssym;
7023 bfd_size_type count;
7024 unsigned int st_shndx;
7027 struct elf_symbol
7029 union
7031 Elf_Internal_Sym *isym;
7032 struct elf_symbuf_symbol *ssym;
7033 } u;
7034 const char *name;
7037 /* Sort references to symbols by ascending section number. */
7039 static int
7040 elf_sort_elf_symbol (const void *arg1, const void *arg2)
7042 const Elf_Internal_Sym *s1 = *(const Elf_Internal_Sym **) arg1;
7043 const Elf_Internal_Sym *s2 = *(const Elf_Internal_Sym **) arg2;
7045 return s1->st_shndx - s2->st_shndx;
7048 static int
7049 elf_sym_name_compare (const void *arg1, const void *arg2)
7051 const struct elf_symbol *s1 = (const struct elf_symbol *) arg1;
7052 const struct elf_symbol *s2 = (const struct elf_symbol *) arg2;
7053 return strcmp (s1->name, s2->name);
7056 static struct elf_symbuf_head *
7057 elf_create_symbuf (bfd_size_type symcount, Elf_Internal_Sym *isymbuf)
7059 Elf_Internal_Sym **ind, **indbufend, **indbuf;
7060 struct elf_symbuf_symbol *ssym;
7061 struct elf_symbuf_head *ssymbuf, *ssymhead;
7062 bfd_size_type i, shndx_count, total_size;
7064 indbuf = (Elf_Internal_Sym **) bfd_malloc2 (symcount, sizeof (*indbuf));
7065 if (indbuf == NULL)
7066 return NULL;
7068 for (ind = indbuf, i = 0; i < symcount; i++)
7069 if (isymbuf[i].st_shndx != SHN_UNDEF)
7070 *ind++ = &isymbuf[i];
7071 indbufend = ind;
7073 qsort (indbuf, indbufend - indbuf, sizeof (Elf_Internal_Sym *),
7074 elf_sort_elf_symbol);
7076 shndx_count = 0;
7077 if (indbufend > indbuf)
7078 for (ind = indbuf, shndx_count++; ind < indbufend - 1; ind++)
7079 if (ind[0]->st_shndx != ind[1]->st_shndx)
7080 shndx_count++;
7082 total_size = ((shndx_count + 1) * sizeof (*ssymbuf)
7083 + (indbufend - indbuf) * sizeof (*ssym));
7084 ssymbuf = (struct elf_symbuf_head *) bfd_malloc (total_size);
7085 if (ssymbuf == NULL)
7087 free (indbuf);
7088 return NULL;
7091 ssym = (struct elf_symbuf_symbol *) (ssymbuf + shndx_count + 1);
7092 ssymbuf->ssym = NULL;
7093 ssymbuf->count = shndx_count;
7094 ssymbuf->st_shndx = 0;
7095 for (ssymhead = ssymbuf, ind = indbuf; ind < indbufend; ssym++, ind++)
7097 if (ind == indbuf || ssymhead->st_shndx != (*ind)->st_shndx)
7099 ssymhead++;
7100 ssymhead->ssym = ssym;
7101 ssymhead->count = 0;
7102 ssymhead->st_shndx = (*ind)->st_shndx;
7104 ssym->st_name = (*ind)->st_name;
7105 ssym->st_info = (*ind)->st_info;
7106 ssym->st_other = (*ind)->st_other;
7107 ssymhead->count++;
7109 BFD_ASSERT ((bfd_size_type) (ssymhead - ssymbuf) == shndx_count
7110 && (((bfd_hostptr_t) ssym - (bfd_hostptr_t) ssymbuf)
7111 == total_size));
7113 free (indbuf);
7114 return ssymbuf;
7117 /* Check if 2 sections define the same set of local and global
7118 symbols. */
7120 static bfd_boolean
7121 bfd_elf_match_symbols_in_sections (asection *sec1, asection *sec2,
7122 struct bfd_link_info *info)
7124 bfd *bfd1, *bfd2;
7125 const struct elf_backend_data *bed1, *bed2;
7126 Elf_Internal_Shdr *hdr1, *hdr2;
7127 bfd_size_type symcount1, symcount2;
7128 Elf_Internal_Sym *isymbuf1, *isymbuf2;
7129 struct elf_symbuf_head *ssymbuf1, *ssymbuf2;
7130 Elf_Internal_Sym *isym, *isymend;
7131 struct elf_symbol *symtable1 = NULL, *symtable2 = NULL;
7132 bfd_size_type count1, count2, i;
7133 unsigned int shndx1, shndx2;
7134 bfd_boolean result;
7136 bfd1 = sec1->owner;
7137 bfd2 = sec2->owner;
7139 /* Both sections have to be in ELF. */
7140 if (bfd_get_flavour (bfd1) != bfd_target_elf_flavour
7141 || bfd_get_flavour (bfd2) != bfd_target_elf_flavour)
7142 return FALSE;
7144 if (elf_section_type (sec1) != elf_section_type (sec2))
7145 return FALSE;
7147 shndx1 = _bfd_elf_section_from_bfd_section (bfd1, sec1);
7148 shndx2 = _bfd_elf_section_from_bfd_section (bfd2, sec2);
7149 if (shndx1 == SHN_BAD || shndx2 == SHN_BAD)
7150 return FALSE;
7152 bed1 = get_elf_backend_data (bfd1);
7153 bed2 = get_elf_backend_data (bfd2);
7154 hdr1 = &elf_tdata (bfd1)->symtab_hdr;
7155 symcount1 = hdr1->sh_size / bed1->s->sizeof_sym;
7156 hdr2 = &elf_tdata (bfd2)->symtab_hdr;
7157 symcount2 = hdr2->sh_size / bed2->s->sizeof_sym;
7159 if (symcount1 == 0 || symcount2 == 0)
7160 return FALSE;
7162 result = FALSE;
7163 isymbuf1 = NULL;
7164 isymbuf2 = NULL;
7165 ssymbuf1 = (struct elf_symbuf_head *) elf_tdata (bfd1)->symbuf;
7166 ssymbuf2 = (struct elf_symbuf_head *) elf_tdata (bfd2)->symbuf;
7168 if (ssymbuf1 == NULL)
7170 isymbuf1 = bfd_elf_get_elf_syms (bfd1, hdr1, symcount1, 0,
7171 NULL, NULL, NULL);
7172 if (isymbuf1 == NULL)
7173 goto done;
7175 if (!info->reduce_memory_overheads)
7176 elf_tdata (bfd1)->symbuf = ssymbuf1
7177 = elf_create_symbuf (symcount1, isymbuf1);
7180 if (ssymbuf1 == NULL || ssymbuf2 == NULL)
7182 isymbuf2 = bfd_elf_get_elf_syms (bfd2, hdr2, symcount2, 0,
7183 NULL, NULL, NULL);
7184 if (isymbuf2 == NULL)
7185 goto done;
7187 if (ssymbuf1 != NULL && !info->reduce_memory_overheads)
7188 elf_tdata (bfd2)->symbuf = ssymbuf2
7189 = elf_create_symbuf (symcount2, isymbuf2);
7192 if (ssymbuf1 != NULL && ssymbuf2 != NULL)
7194 /* Optimized faster version. */
7195 bfd_size_type lo, hi, mid;
7196 struct elf_symbol *symp;
7197 struct elf_symbuf_symbol *ssym, *ssymend;
7199 lo = 0;
7200 hi = ssymbuf1->count;
7201 ssymbuf1++;
7202 count1 = 0;
7203 while (lo < hi)
7205 mid = (lo + hi) / 2;
7206 if (shndx1 < ssymbuf1[mid].st_shndx)
7207 hi = mid;
7208 else if (shndx1 > ssymbuf1[mid].st_shndx)
7209 lo = mid + 1;
7210 else
7212 count1 = ssymbuf1[mid].count;
7213 ssymbuf1 += mid;
7214 break;
7218 lo = 0;
7219 hi = ssymbuf2->count;
7220 ssymbuf2++;
7221 count2 = 0;
7222 while (lo < hi)
7224 mid = (lo + hi) / 2;
7225 if (shndx2 < ssymbuf2[mid].st_shndx)
7226 hi = mid;
7227 else if (shndx2 > ssymbuf2[mid].st_shndx)
7228 lo = mid + 1;
7229 else
7231 count2 = ssymbuf2[mid].count;
7232 ssymbuf2 += mid;
7233 break;
7237 if (count1 == 0 || count2 == 0 || count1 != count2)
7238 goto done;
7240 symtable1 = (struct elf_symbol *)
7241 bfd_malloc (count1 * sizeof (struct elf_symbol));
7242 symtable2 = (struct elf_symbol *)
7243 bfd_malloc (count2 * sizeof (struct elf_symbol));
7244 if (symtable1 == NULL || symtable2 == NULL)
7245 goto done;
7247 symp = symtable1;
7248 for (ssym = ssymbuf1->ssym, ssymend = ssym + count1;
7249 ssym < ssymend; ssym++, symp++)
7251 symp->u.ssym = ssym;
7252 symp->name = bfd_elf_string_from_elf_section (bfd1,
7253 hdr1->sh_link,
7254 ssym->st_name);
7257 symp = symtable2;
7258 for (ssym = ssymbuf2->ssym, ssymend = ssym + count2;
7259 ssym < ssymend; ssym++, symp++)
7261 symp->u.ssym = ssym;
7262 symp->name = bfd_elf_string_from_elf_section (bfd2,
7263 hdr2->sh_link,
7264 ssym->st_name);
7267 /* Sort symbol by name. */
7268 qsort (symtable1, count1, sizeof (struct elf_symbol),
7269 elf_sym_name_compare);
7270 qsort (symtable2, count1, sizeof (struct elf_symbol),
7271 elf_sym_name_compare);
7273 for (i = 0; i < count1; i++)
7274 /* Two symbols must have the same binding, type and name. */
7275 if (symtable1 [i].u.ssym->st_info != symtable2 [i].u.ssym->st_info
7276 || symtable1 [i].u.ssym->st_other != symtable2 [i].u.ssym->st_other
7277 || strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
7278 goto done;
7280 result = TRUE;
7281 goto done;
7284 symtable1 = (struct elf_symbol *)
7285 bfd_malloc (symcount1 * sizeof (struct elf_symbol));
7286 symtable2 = (struct elf_symbol *)
7287 bfd_malloc (symcount2 * sizeof (struct elf_symbol));
7288 if (symtable1 == NULL || symtable2 == NULL)
7289 goto done;
7291 /* Count definitions in the section. */
7292 count1 = 0;
7293 for (isym = isymbuf1, isymend = isym + symcount1; isym < isymend; isym++)
7294 if (isym->st_shndx == shndx1)
7295 symtable1[count1++].u.isym = isym;
7297 count2 = 0;
7298 for (isym = isymbuf2, isymend = isym + symcount2; isym < isymend; isym++)
7299 if (isym->st_shndx == shndx2)
7300 symtable2[count2++].u.isym = isym;
7302 if (count1 == 0 || count2 == 0 || count1 != count2)
7303 goto done;
7305 for (i = 0; i < count1; i++)
7306 symtable1[i].name
7307 = bfd_elf_string_from_elf_section (bfd1, hdr1->sh_link,
7308 symtable1[i].u.isym->st_name);
7310 for (i = 0; i < count2; i++)
7311 symtable2[i].name
7312 = bfd_elf_string_from_elf_section (bfd2, hdr2->sh_link,
7313 symtable2[i].u.isym->st_name);
7315 /* Sort symbol by name. */
7316 qsort (symtable1, count1, sizeof (struct elf_symbol),
7317 elf_sym_name_compare);
7318 qsort (symtable2, count1, sizeof (struct elf_symbol),
7319 elf_sym_name_compare);
7321 for (i = 0; i < count1; i++)
7322 /* Two symbols must have the same binding, type and name. */
7323 if (symtable1 [i].u.isym->st_info != symtable2 [i].u.isym->st_info
7324 || symtable1 [i].u.isym->st_other != symtable2 [i].u.isym->st_other
7325 || strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
7326 goto done;
7328 result = TRUE;
7330 done:
7331 if (symtable1)
7332 free (symtable1);
7333 if (symtable2)
7334 free (symtable2);
7335 if (isymbuf1)
7336 free (isymbuf1);
7337 if (isymbuf2)
7338 free (isymbuf2);
7340 return result;
7343 /* Return TRUE if 2 section types are compatible. */
7345 bfd_boolean
7346 _bfd_elf_match_sections_by_type (bfd *abfd, const asection *asec,
7347 bfd *bbfd, const asection *bsec)
7349 if (asec == NULL
7350 || bsec == NULL
7351 || abfd->xvec->flavour != bfd_target_elf_flavour
7352 || bbfd->xvec->flavour != bfd_target_elf_flavour)
7353 return TRUE;
7355 return elf_section_type (asec) == elf_section_type (bsec);
7358 /* Final phase of ELF linker. */
7360 /* A structure we use to avoid passing large numbers of arguments. */
7362 struct elf_final_link_info
7364 /* General link information. */
7365 struct bfd_link_info *info;
7366 /* Output BFD. */
7367 bfd *output_bfd;
7368 /* Symbol string table. */
7369 struct bfd_strtab_hash *symstrtab;
7370 /* .dynsym section. */
7371 asection *dynsym_sec;
7372 /* .hash section. */
7373 asection *hash_sec;
7374 /* symbol version section (.gnu.version). */
7375 asection *symver_sec;
7376 /* Buffer large enough to hold contents of any section. */
7377 bfd_byte *contents;
7378 /* Buffer large enough to hold external relocs of any section. */
7379 void *external_relocs;
7380 /* Buffer large enough to hold internal relocs of any section. */
7381 Elf_Internal_Rela *internal_relocs;
7382 /* Buffer large enough to hold external local symbols of any input
7383 BFD. */
7384 bfd_byte *external_syms;
7385 /* And a buffer for symbol section indices. */
7386 Elf_External_Sym_Shndx *locsym_shndx;
7387 /* Buffer large enough to hold internal local symbols of any input
7388 BFD. */
7389 Elf_Internal_Sym *internal_syms;
7390 /* Array large enough to hold a symbol index for each local symbol
7391 of any input BFD. */
7392 long *indices;
7393 /* Array large enough to hold a section pointer for each local
7394 symbol of any input BFD. */
7395 asection **sections;
7396 /* Buffer to hold swapped out symbols. */
7397 bfd_byte *symbuf;
7398 /* And one for symbol section indices. */
7399 Elf_External_Sym_Shndx *symshndxbuf;
7400 /* Number of swapped out symbols in buffer. */
7401 size_t symbuf_count;
7402 /* Number of symbols which fit in symbuf. */
7403 size_t symbuf_size;
7404 /* And same for symshndxbuf. */
7405 size_t shndxbuf_size;
7408 /* This struct is used to pass information to elf_link_output_extsym. */
7410 struct elf_outext_info
7412 bfd_boolean failed;
7413 bfd_boolean localsyms;
7414 struct elf_final_link_info *finfo;
7418 /* Support for evaluating a complex relocation.
7420 Complex relocations are generalized, self-describing relocations. The
7421 implementation of them consists of two parts: complex symbols, and the
7422 relocations themselves.
7424 The relocations are use a reserved elf-wide relocation type code (R_RELC
7425 external / BFD_RELOC_RELC internal) and an encoding of relocation field
7426 information (start bit, end bit, word width, etc) into the addend. This
7427 information is extracted from CGEN-generated operand tables within gas.
7429 Complex symbols are mangled symbols (BSF_RELC external / STT_RELC
7430 internal) representing prefix-notation expressions, including but not
7431 limited to those sorts of expressions normally encoded as addends in the
7432 addend field. The symbol mangling format is:
7434 <node> := <literal>
7435 | <unary-operator> ':' <node>
7436 | <binary-operator> ':' <node> ':' <node>
7439 <literal> := 's' <digits=N> ':' <N character symbol name>
7440 | 'S' <digits=N> ':' <N character section name>
7441 | '#' <hexdigits>
7444 <binary-operator> := as in C
7445 <unary-operator> := as in C, plus "0-" for unambiguous negation. */
7447 static void
7448 set_symbol_value (bfd *bfd_with_globals,
7449 Elf_Internal_Sym *isymbuf,
7450 size_t locsymcount,
7451 size_t symidx,
7452 bfd_vma val)
7454 struct elf_link_hash_entry **sym_hashes;
7455 struct elf_link_hash_entry *h;
7456 size_t extsymoff = locsymcount;
7458 if (symidx < locsymcount)
7460 Elf_Internal_Sym *sym;
7462 sym = isymbuf + symidx;
7463 if (ELF_ST_BIND (sym->st_info) == STB_LOCAL)
7465 /* It is a local symbol: move it to the
7466 "absolute" section and give it a value. */
7467 sym->st_shndx = SHN_ABS;
7468 sym->st_value = val;
7469 return;
7471 BFD_ASSERT (elf_bad_symtab (bfd_with_globals));
7472 extsymoff = 0;
7475 /* It is a global symbol: set its link type
7476 to "defined" and give it a value. */
7478 sym_hashes = elf_sym_hashes (bfd_with_globals);
7479 h = sym_hashes [symidx - extsymoff];
7480 while (h->root.type == bfd_link_hash_indirect
7481 || h->root.type == bfd_link_hash_warning)
7482 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7483 h->root.type = bfd_link_hash_defined;
7484 h->root.u.def.value = val;
7485 h->root.u.def.section = bfd_abs_section_ptr;
7488 static bfd_boolean
7489 resolve_symbol (const char *name,
7490 bfd *input_bfd,
7491 struct elf_final_link_info *finfo,
7492 bfd_vma *result,
7493 Elf_Internal_Sym *isymbuf,
7494 size_t locsymcount)
7496 Elf_Internal_Sym *sym;
7497 struct bfd_link_hash_entry *global_entry;
7498 const char *candidate = NULL;
7499 Elf_Internal_Shdr *symtab_hdr;
7500 size_t i;
7502 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
7504 for (i = 0; i < locsymcount; ++ i)
7506 sym = isymbuf + i;
7508 if (ELF_ST_BIND (sym->st_info) != STB_LOCAL)
7509 continue;
7511 candidate = bfd_elf_string_from_elf_section (input_bfd,
7512 symtab_hdr->sh_link,
7513 sym->st_name);
7514 #ifdef DEBUG
7515 printf ("Comparing string: '%s' vs. '%s' = 0x%lx\n",
7516 name, candidate, (unsigned long) sym->st_value);
7517 #endif
7518 if (candidate && strcmp (candidate, name) == 0)
7520 asection *sec = finfo->sections [i];
7522 *result = _bfd_elf_rel_local_sym (input_bfd, sym, &sec, 0);
7523 *result += sec->output_offset + sec->output_section->vma;
7524 #ifdef DEBUG
7525 printf ("Found symbol with value %8.8lx\n",
7526 (unsigned long) *result);
7527 #endif
7528 return TRUE;
7532 /* Hmm, haven't found it yet. perhaps it is a global. */
7533 global_entry = bfd_link_hash_lookup (finfo->info->hash, name,
7534 FALSE, FALSE, TRUE);
7535 if (!global_entry)
7536 return FALSE;
7538 if (global_entry->type == bfd_link_hash_defined
7539 || global_entry->type == bfd_link_hash_defweak)
7541 *result = (global_entry->u.def.value
7542 + global_entry->u.def.section->output_section->vma
7543 + global_entry->u.def.section->output_offset);
7544 #ifdef DEBUG
7545 printf ("Found GLOBAL symbol '%s' with value %8.8lx\n",
7546 global_entry->root.string, (unsigned long) *result);
7547 #endif
7548 return TRUE;
7551 return FALSE;
7554 static bfd_boolean
7555 resolve_section (const char *name,
7556 asection *sections,
7557 bfd_vma *result)
7559 asection *curr;
7560 unsigned int len;
7562 for (curr = sections; curr; curr = curr->next)
7563 if (strcmp (curr->name, name) == 0)
7565 *result = curr->vma;
7566 return TRUE;
7569 /* Hmm. still haven't found it. try pseudo-section names. */
7570 for (curr = sections; curr; curr = curr->next)
7572 len = strlen (curr->name);
7573 if (len > strlen (name))
7574 continue;
7576 if (strncmp (curr->name, name, len) == 0)
7578 if (strncmp (".end", name + len, 4) == 0)
7580 *result = curr->vma + curr->size;
7581 return TRUE;
7584 /* Insert more pseudo-section names here, if you like. */
7588 return FALSE;
7591 static void
7592 undefined_reference (const char *reftype, const char *name)
7594 _bfd_error_handler (_("undefined %s reference in complex symbol: %s"),
7595 reftype, name);
7598 static bfd_boolean
7599 eval_symbol (bfd_vma *result,
7600 const char **symp,
7601 bfd *input_bfd,
7602 struct elf_final_link_info *finfo,
7603 bfd_vma dot,
7604 Elf_Internal_Sym *isymbuf,
7605 size_t locsymcount,
7606 int signed_p)
7608 size_t len;
7609 size_t symlen;
7610 bfd_vma a;
7611 bfd_vma b;
7612 char symbuf[4096];
7613 const char *sym = *symp;
7614 const char *symend;
7615 bfd_boolean symbol_is_section = FALSE;
7617 len = strlen (sym);
7618 symend = sym + len;
7620 if (len < 1 || len > sizeof (symbuf))
7622 bfd_set_error (bfd_error_invalid_operation);
7623 return FALSE;
7626 switch (* sym)
7628 case '.':
7629 *result = dot;
7630 *symp = sym + 1;
7631 return TRUE;
7633 case '#':
7634 ++sym;
7635 *result = strtoul (sym, (char **) symp, 16);
7636 return TRUE;
7638 case 'S':
7639 symbol_is_section = TRUE;
7640 case 's':
7641 ++sym;
7642 symlen = strtol (sym, (char **) symp, 10);
7643 sym = *symp + 1; /* Skip the trailing ':'. */
7645 if (symend < sym || symlen + 1 > sizeof (symbuf))
7647 bfd_set_error (bfd_error_invalid_operation);
7648 return FALSE;
7651 memcpy (symbuf, sym, symlen);
7652 symbuf[symlen] = '\0';
7653 *symp = sym + symlen;
7655 /* Is it always possible, with complex symbols, that gas "mis-guessed"
7656 the symbol as a section, or vice-versa. so we're pretty liberal in our
7657 interpretation here; section means "try section first", not "must be a
7658 section", and likewise with symbol. */
7660 if (symbol_is_section)
7662 if (!resolve_section (symbuf, finfo->output_bfd->sections, result)
7663 && !resolve_symbol (symbuf, input_bfd, finfo, result,
7664 isymbuf, locsymcount))
7666 undefined_reference ("section", symbuf);
7667 return FALSE;
7670 else
7672 if (!resolve_symbol (symbuf, input_bfd, finfo, result,
7673 isymbuf, locsymcount)
7674 && !resolve_section (symbuf, finfo->output_bfd->sections,
7675 result))
7677 undefined_reference ("symbol", symbuf);
7678 return FALSE;
7682 return TRUE;
7684 /* All that remains are operators. */
7686 #define UNARY_OP(op) \
7687 if (strncmp (sym, #op, strlen (#op)) == 0) \
7689 sym += strlen (#op); \
7690 if (*sym == ':') \
7691 ++sym; \
7692 *symp = sym; \
7693 if (!eval_symbol (&a, symp, input_bfd, finfo, dot, \
7694 isymbuf, locsymcount, signed_p)) \
7695 return FALSE; \
7696 if (signed_p) \
7697 *result = op ((bfd_signed_vma) a); \
7698 else \
7699 *result = op a; \
7700 return TRUE; \
7703 #define BINARY_OP(op) \
7704 if (strncmp (sym, #op, strlen (#op)) == 0) \
7706 sym += strlen (#op); \
7707 if (*sym == ':') \
7708 ++sym; \
7709 *symp = sym; \
7710 if (!eval_symbol (&a, symp, input_bfd, finfo, dot, \
7711 isymbuf, locsymcount, signed_p)) \
7712 return FALSE; \
7713 ++*symp; \
7714 if (!eval_symbol (&b, symp, input_bfd, finfo, dot, \
7715 isymbuf, locsymcount, signed_p)) \
7716 return FALSE; \
7717 if (signed_p) \
7718 *result = ((bfd_signed_vma) a) op ((bfd_signed_vma) b); \
7719 else \
7720 *result = a op b; \
7721 return TRUE; \
7724 default:
7725 UNARY_OP (0-);
7726 BINARY_OP (<<);
7727 BINARY_OP (>>);
7728 BINARY_OP (==);
7729 BINARY_OP (!=);
7730 BINARY_OP (<=);
7731 BINARY_OP (>=);
7732 BINARY_OP (&&);
7733 BINARY_OP (||);
7734 UNARY_OP (~);
7735 UNARY_OP (!);
7736 BINARY_OP (*);
7737 BINARY_OP (/);
7738 BINARY_OP (%);
7739 BINARY_OP (^);
7740 BINARY_OP (|);
7741 BINARY_OP (&);
7742 BINARY_OP (+);
7743 BINARY_OP (-);
7744 BINARY_OP (<);
7745 BINARY_OP (>);
7746 #undef UNARY_OP
7747 #undef BINARY_OP
7748 _bfd_error_handler (_("unknown operator '%c' in complex symbol"), * sym);
7749 bfd_set_error (bfd_error_invalid_operation);
7750 return FALSE;
7754 static void
7755 put_value (bfd_vma size,
7756 unsigned long chunksz,
7757 bfd *input_bfd,
7758 bfd_vma x,
7759 bfd_byte *location)
7761 location += (size - chunksz);
7763 for (; size; size -= chunksz, location -= chunksz, x >>= (chunksz * 8))
7765 switch (chunksz)
7767 default:
7768 case 0:
7769 abort ();
7770 case 1:
7771 bfd_put_8 (input_bfd, x, location);
7772 break;
7773 case 2:
7774 bfd_put_16 (input_bfd, x, location);
7775 break;
7776 case 4:
7777 bfd_put_32 (input_bfd, x, location);
7778 break;
7779 case 8:
7780 #ifdef BFD64
7781 bfd_put_64 (input_bfd, x, location);
7782 #else
7783 abort ();
7784 #endif
7785 break;
7790 static bfd_vma
7791 get_value (bfd_vma size,
7792 unsigned long chunksz,
7793 bfd *input_bfd,
7794 bfd_byte *location)
7796 bfd_vma x = 0;
7798 for (; size; size -= chunksz, location += chunksz)
7800 switch (chunksz)
7802 default:
7803 case 0:
7804 abort ();
7805 case 1:
7806 x = (x << (8 * chunksz)) | bfd_get_8 (input_bfd, location);
7807 break;
7808 case 2:
7809 x = (x << (8 * chunksz)) | bfd_get_16 (input_bfd, location);
7810 break;
7811 case 4:
7812 x = (x << (8 * chunksz)) | bfd_get_32 (input_bfd, location);
7813 break;
7814 case 8:
7815 #ifdef BFD64
7816 x = (x << (8 * chunksz)) | bfd_get_64 (input_bfd, location);
7817 #else
7818 abort ();
7819 #endif
7820 break;
7823 return x;
7826 static void
7827 decode_complex_addend (unsigned long *start, /* in bits */
7828 unsigned long *oplen, /* in bits */
7829 unsigned long *len, /* in bits */
7830 unsigned long *wordsz, /* in bytes */
7831 unsigned long *chunksz, /* in bytes */
7832 unsigned long *lsb0_p,
7833 unsigned long *signed_p,
7834 unsigned long *trunc_p,
7835 unsigned long encoded)
7837 * start = encoded & 0x3F;
7838 * len = (encoded >> 6) & 0x3F;
7839 * oplen = (encoded >> 12) & 0x3F;
7840 * wordsz = (encoded >> 18) & 0xF;
7841 * chunksz = (encoded >> 22) & 0xF;
7842 * lsb0_p = (encoded >> 27) & 1;
7843 * signed_p = (encoded >> 28) & 1;
7844 * trunc_p = (encoded >> 29) & 1;
7847 bfd_reloc_status_type
7848 bfd_elf_perform_complex_relocation (bfd *input_bfd,
7849 asection *input_section ATTRIBUTE_UNUSED,
7850 bfd_byte *contents,
7851 Elf_Internal_Rela *rel,
7852 bfd_vma relocation)
7854 bfd_vma shift, x, mask;
7855 unsigned long start, oplen, len, wordsz, chunksz, lsb0_p, signed_p, trunc_p;
7856 bfd_reloc_status_type r;
7858 /* Perform this reloc, since it is complex.
7859 (this is not to say that it necessarily refers to a complex
7860 symbol; merely that it is a self-describing CGEN based reloc.
7861 i.e. the addend has the complete reloc information (bit start, end,
7862 word size, etc) encoded within it.). */
7864 decode_complex_addend (&start, &oplen, &len, &wordsz,
7865 &chunksz, &lsb0_p, &signed_p,
7866 &trunc_p, rel->r_addend);
7868 mask = (((1L << (len - 1)) - 1) << 1) | 1;
7870 if (lsb0_p)
7871 shift = (start + 1) - len;
7872 else
7873 shift = (8 * wordsz) - (start + len);
7875 /* FIXME: octets_per_byte. */
7876 x = get_value (wordsz, chunksz, input_bfd, contents + rel->r_offset);
7878 #ifdef DEBUG
7879 printf ("Doing complex reloc: "
7880 "lsb0? %ld, signed? %ld, trunc? %ld, wordsz %ld, "
7881 "chunksz %ld, start %ld, len %ld, oplen %ld\n"
7882 " dest: %8.8lx, mask: %8.8lx, reloc: %8.8lx\n",
7883 lsb0_p, signed_p, trunc_p, wordsz, chunksz, start, len,
7884 oplen, x, mask, relocation);
7885 #endif
7887 r = bfd_reloc_ok;
7888 if (! trunc_p)
7889 /* Now do an overflow check. */
7890 r = bfd_check_overflow ((signed_p
7891 ? complain_overflow_signed
7892 : complain_overflow_unsigned),
7893 len, 0, (8 * wordsz),
7894 relocation);
7896 /* Do the deed. */
7897 x = (x & ~(mask << shift)) | ((relocation & mask) << shift);
7899 #ifdef DEBUG
7900 printf (" relocation: %8.8lx\n"
7901 " shifted mask: %8.8lx\n"
7902 " shifted/masked reloc: %8.8lx\n"
7903 " result: %8.8lx\n",
7904 relocation, (mask << shift),
7905 ((relocation & mask) << shift), x);
7906 #endif
7907 /* FIXME: octets_per_byte. */
7908 put_value (wordsz, chunksz, input_bfd, x, contents + rel->r_offset);
7909 return r;
7912 /* When performing a relocatable link, the input relocations are
7913 preserved. But, if they reference global symbols, the indices
7914 referenced must be updated. Update all the relocations in
7915 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
7917 static void
7918 elf_link_adjust_relocs (bfd *abfd,
7919 Elf_Internal_Shdr *rel_hdr,
7920 unsigned int count,
7921 struct elf_link_hash_entry **rel_hash)
7923 unsigned int i;
7924 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7925 bfd_byte *erela;
7926 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
7927 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
7928 bfd_vma r_type_mask;
7929 int r_sym_shift;
7931 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
7933 swap_in = bed->s->swap_reloc_in;
7934 swap_out = bed->s->swap_reloc_out;
7936 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
7938 swap_in = bed->s->swap_reloca_in;
7939 swap_out = bed->s->swap_reloca_out;
7941 else
7942 abort ();
7944 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
7945 abort ();
7947 if (bed->s->arch_size == 32)
7949 r_type_mask = 0xff;
7950 r_sym_shift = 8;
7952 else
7954 r_type_mask = 0xffffffff;
7955 r_sym_shift = 32;
7958 erela = rel_hdr->contents;
7959 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
7961 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
7962 unsigned int j;
7964 if (*rel_hash == NULL)
7965 continue;
7967 BFD_ASSERT ((*rel_hash)->indx >= 0);
7969 (*swap_in) (abfd, erela, irela);
7970 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
7971 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
7972 | (irela[j].r_info & r_type_mask));
7973 (*swap_out) (abfd, irela, erela);
7977 struct elf_link_sort_rela
7979 union {
7980 bfd_vma offset;
7981 bfd_vma sym_mask;
7982 } u;
7983 enum elf_reloc_type_class type;
7984 /* We use this as an array of size int_rels_per_ext_rel. */
7985 Elf_Internal_Rela rela[1];
7988 static int
7989 elf_link_sort_cmp1 (const void *A, const void *B)
7991 const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
7992 const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
7993 int relativea, relativeb;
7995 relativea = a->type == reloc_class_relative;
7996 relativeb = b->type == reloc_class_relative;
7998 if (relativea < relativeb)
7999 return 1;
8000 if (relativea > relativeb)
8001 return -1;
8002 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
8003 return -1;
8004 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
8005 return 1;
8006 if (a->rela->r_offset < b->rela->r_offset)
8007 return -1;
8008 if (a->rela->r_offset > b->rela->r_offset)
8009 return 1;
8010 return 0;
8013 static int
8014 elf_link_sort_cmp2 (const void *A, const void *B)
8016 const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
8017 const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
8018 int copya, copyb;
8020 if (a->u.offset < b->u.offset)
8021 return -1;
8022 if (a->u.offset > b->u.offset)
8023 return 1;
8024 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
8025 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
8026 if (copya < copyb)
8027 return -1;
8028 if (copya > copyb)
8029 return 1;
8030 if (a->rela->r_offset < b->rela->r_offset)
8031 return -1;
8032 if (a->rela->r_offset > b->rela->r_offset)
8033 return 1;
8034 return 0;
8037 static size_t
8038 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
8040 asection *dynamic_relocs;
8041 asection *rela_dyn;
8042 asection *rel_dyn;
8043 bfd_size_type count, size;
8044 size_t i, ret, sort_elt, ext_size;
8045 bfd_byte *sort, *s_non_relative, *p;
8046 struct elf_link_sort_rela *sq;
8047 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8048 int i2e = bed->s->int_rels_per_ext_rel;
8049 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
8050 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
8051 struct bfd_link_order *lo;
8052 bfd_vma r_sym_mask;
8053 bfd_boolean use_rela;
8055 /* Find a dynamic reloc section. */
8056 rela_dyn = bfd_get_section_by_name (abfd, ".rela.dyn");
8057 rel_dyn = bfd_get_section_by_name (abfd, ".rel.dyn");
8058 if (rela_dyn != NULL && rela_dyn->size > 0
8059 && rel_dyn != NULL && rel_dyn->size > 0)
8061 bfd_boolean use_rela_initialised = FALSE;
8063 /* This is just here to stop gcc from complaining.
8064 It's initialization checking code is not perfect. */
8065 use_rela = TRUE;
8067 /* Both sections are present. Examine the sizes
8068 of the indirect sections to help us choose. */
8069 for (lo = rela_dyn->map_head.link_order; lo != NULL; lo = lo->next)
8070 if (lo->type == bfd_indirect_link_order)
8072 asection *o = lo->u.indirect.section;
8074 if ((o->size % bed->s->sizeof_rela) == 0)
8076 if ((o->size % bed->s->sizeof_rel) == 0)
8077 /* Section size is divisible by both rel and rela sizes.
8078 It is of no help to us. */
8080 else
8082 /* Section size is only divisible by rela. */
8083 if (use_rela_initialised && (use_rela == FALSE))
8085 _bfd_error_handler
8086 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
8087 bfd_set_error (bfd_error_invalid_operation);
8088 return 0;
8090 else
8092 use_rela = TRUE;
8093 use_rela_initialised = TRUE;
8097 else if ((o->size % bed->s->sizeof_rel) == 0)
8099 /* Section size is only divisible by rel. */
8100 if (use_rela_initialised && (use_rela == TRUE))
8102 _bfd_error_handler
8103 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
8104 bfd_set_error (bfd_error_invalid_operation);
8105 return 0;
8107 else
8109 use_rela = FALSE;
8110 use_rela_initialised = TRUE;
8113 else
8115 /* The section size is not divisible by either - something is wrong. */
8116 _bfd_error_handler
8117 (_("%B: Unable to sort relocs - they are of an unknown size"), abfd);
8118 bfd_set_error (bfd_error_invalid_operation);
8119 return 0;
8123 for (lo = rel_dyn->map_head.link_order; lo != NULL; lo = lo->next)
8124 if (lo->type == bfd_indirect_link_order)
8126 asection *o = lo->u.indirect.section;
8128 if ((o->size % bed->s->sizeof_rela) == 0)
8130 if ((o->size % bed->s->sizeof_rel) == 0)
8131 /* Section size is divisible by both rel and rela sizes.
8132 It is of no help to us. */
8134 else
8136 /* Section size is only divisible by rela. */
8137 if (use_rela_initialised && (use_rela == FALSE))
8139 _bfd_error_handler
8140 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
8141 bfd_set_error (bfd_error_invalid_operation);
8142 return 0;
8144 else
8146 use_rela = TRUE;
8147 use_rela_initialised = TRUE;
8151 else if ((o->size % bed->s->sizeof_rel) == 0)
8153 /* Section size is only divisible by rel. */
8154 if (use_rela_initialised && (use_rela == TRUE))
8156 _bfd_error_handler
8157 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
8158 bfd_set_error (bfd_error_invalid_operation);
8159 return 0;
8161 else
8163 use_rela = FALSE;
8164 use_rela_initialised = TRUE;
8167 else
8169 /* The section size is not divisible by either - something is wrong. */
8170 _bfd_error_handler
8171 (_("%B: Unable to sort relocs - they are of an unknown size"), abfd);
8172 bfd_set_error (bfd_error_invalid_operation);
8173 return 0;
8177 if (! use_rela_initialised)
8178 /* Make a guess. */
8179 use_rela = TRUE;
8181 else if (rela_dyn != NULL && rela_dyn->size > 0)
8182 use_rela = TRUE;
8183 else if (rel_dyn != NULL && rel_dyn->size > 0)
8184 use_rela = FALSE;
8185 else
8186 return 0;
8188 if (use_rela)
8190 dynamic_relocs = rela_dyn;
8191 ext_size = bed->s->sizeof_rela;
8192 swap_in = bed->s->swap_reloca_in;
8193 swap_out = bed->s->swap_reloca_out;
8195 else
8197 dynamic_relocs = rel_dyn;
8198 ext_size = bed->s->sizeof_rel;
8199 swap_in = bed->s->swap_reloc_in;
8200 swap_out = bed->s->swap_reloc_out;
8203 size = 0;
8204 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
8205 if (lo->type == bfd_indirect_link_order)
8206 size += lo->u.indirect.section->size;
8208 if (size != dynamic_relocs->size)
8209 return 0;
8211 sort_elt = (sizeof (struct elf_link_sort_rela)
8212 + (i2e - 1) * sizeof (Elf_Internal_Rela));
8214 count = dynamic_relocs->size / ext_size;
8215 if (count == 0)
8216 return 0;
8217 sort = (bfd_byte *) bfd_zmalloc (sort_elt * count);
8219 if (sort == NULL)
8221 (*info->callbacks->warning)
8222 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
8223 return 0;
8226 if (bed->s->arch_size == 32)
8227 r_sym_mask = ~(bfd_vma) 0xff;
8228 else
8229 r_sym_mask = ~(bfd_vma) 0xffffffff;
8231 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
8232 if (lo->type == bfd_indirect_link_order)
8234 bfd_byte *erel, *erelend;
8235 asection *o = lo->u.indirect.section;
8237 if (o->contents == NULL && o->size != 0)
8239 /* This is a reloc section that is being handled as a normal
8240 section. See bfd_section_from_shdr. We can't combine
8241 relocs in this case. */
8242 free (sort);
8243 return 0;
8245 erel = o->contents;
8246 erelend = o->contents + o->size;
8247 /* FIXME: octets_per_byte. */
8248 p = sort + o->output_offset / ext_size * sort_elt;
8250 while (erel < erelend)
8252 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
8254 (*swap_in) (abfd, erel, s->rela);
8255 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
8256 s->u.sym_mask = r_sym_mask;
8257 p += sort_elt;
8258 erel += ext_size;
8262 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
8264 for (i = 0, p = sort; i < count; i++, p += sort_elt)
8266 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
8267 if (s->type != reloc_class_relative)
8268 break;
8270 ret = i;
8271 s_non_relative = p;
8273 sq = (struct elf_link_sort_rela *) s_non_relative;
8274 for (; i < count; i++, p += sort_elt)
8276 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
8277 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
8278 sq = sp;
8279 sp->u.offset = sq->rela->r_offset;
8282 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
8284 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
8285 if (lo->type == bfd_indirect_link_order)
8287 bfd_byte *erel, *erelend;
8288 asection *o = lo->u.indirect.section;
8290 erel = o->contents;
8291 erelend = o->contents + o->size;
8292 /* FIXME: octets_per_byte. */
8293 p = sort + o->output_offset / ext_size * sort_elt;
8294 while (erel < erelend)
8296 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
8297 (*swap_out) (abfd, s->rela, erel);
8298 p += sort_elt;
8299 erel += ext_size;
8303 free (sort);
8304 *psec = dynamic_relocs;
8305 return ret;
8308 /* Flush the output symbols to the file. */
8310 static bfd_boolean
8311 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
8312 const struct elf_backend_data *bed)
8314 if (finfo->symbuf_count > 0)
8316 Elf_Internal_Shdr *hdr;
8317 file_ptr pos;
8318 bfd_size_type amt;
8320 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
8321 pos = hdr->sh_offset + hdr->sh_size;
8322 amt = finfo->symbuf_count * bed->s->sizeof_sym;
8323 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
8324 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
8325 return FALSE;
8327 hdr->sh_size += amt;
8328 finfo->symbuf_count = 0;
8331 return TRUE;
8334 /* Add a symbol to the output symbol table. */
8336 static int
8337 elf_link_output_sym (struct elf_final_link_info *finfo,
8338 const char *name,
8339 Elf_Internal_Sym *elfsym,
8340 asection *input_sec,
8341 struct elf_link_hash_entry *h)
8343 bfd_byte *dest;
8344 Elf_External_Sym_Shndx *destshndx;
8345 int (*output_symbol_hook)
8346 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
8347 struct elf_link_hash_entry *);
8348 const struct elf_backend_data *bed;
8350 bed = get_elf_backend_data (finfo->output_bfd);
8351 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
8352 if (output_symbol_hook != NULL)
8354 int ret = (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h);
8355 if (ret != 1)
8356 return ret;
8359 if (name == NULL || *name == '\0')
8360 elfsym->st_name = 0;
8361 else if (input_sec->flags & SEC_EXCLUDE)
8362 elfsym->st_name = 0;
8363 else
8365 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
8366 name, TRUE, FALSE);
8367 if (elfsym->st_name == (unsigned long) -1)
8368 return 0;
8371 if (finfo->symbuf_count >= finfo->symbuf_size)
8373 if (! elf_link_flush_output_syms (finfo, bed))
8374 return 0;
8377 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
8378 destshndx = finfo->symshndxbuf;
8379 if (destshndx != NULL)
8381 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
8383 bfd_size_type amt;
8385 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
8386 destshndx = (Elf_External_Sym_Shndx *) bfd_realloc (destshndx,
8387 amt * 2);
8388 if (destshndx == NULL)
8389 return 0;
8390 finfo->symshndxbuf = destshndx;
8391 memset ((char *) destshndx + amt, 0, amt);
8392 finfo->shndxbuf_size *= 2;
8394 destshndx += bfd_get_symcount (finfo->output_bfd);
8397 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
8398 finfo->symbuf_count += 1;
8399 bfd_get_symcount (finfo->output_bfd) += 1;
8401 return 1;
8404 /* Return TRUE if the dynamic symbol SYM in ABFD is supported. */
8406 static bfd_boolean
8407 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
8409 if (sym->st_shndx >= (SHN_LORESERVE & 0xffff)
8410 && sym->st_shndx < SHN_LORESERVE)
8412 /* The gABI doesn't support dynamic symbols in output sections
8413 beyond 64k. */
8414 (*_bfd_error_handler)
8415 (_("%B: Too many sections: %d (>= %d)"),
8416 abfd, bfd_count_sections (abfd), SHN_LORESERVE & 0xffff);
8417 bfd_set_error (bfd_error_nonrepresentable_section);
8418 return FALSE;
8420 return TRUE;
8423 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
8424 allowing an unsatisfied unversioned symbol in the DSO to match a
8425 versioned symbol that would normally require an explicit version.
8426 We also handle the case that a DSO references a hidden symbol
8427 which may be satisfied by a versioned symbol in another DSO. */
8429 static bfd_boolean
8430 elf_link_check_versioned_symbol (struct bfd_link_info *info,
8431 const struct elf_backend_data *bed,
8432 struct elf_link_hash_entry *h)
8434 bfd *abfd;
8435 struct elf_link_loaded_list *loaded;
8437 if (!is_elf_hash_table (info->hash))
8438 return FALSE;
8440 switch (h->root.type)
8442 default:
8443 abfd = NULL;
8444 break;
8446 case bfd_link_hash_undefined:
8447 case bfd_link_hash_undefweak:
8448 abfd = h->root.u.undef.abfd;
8449 if ((abfd->flags & DYNAMIC) == 0
8450 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
8451 return FALSE;
8452 break;
8454 case bfd_link_hash_defined:
8455 case bfd_link_hash_defweak:
8456 abfd = h->root.u.def.section->owner;
8457 break;
8459 case bfd_link_hash_common:
8460 abfd = h->root.u.c.p->section->owner;
8461 break;
8463 BFD_ASSERT (abfd != NULL);
8465 for (loaded = elf_hash_table (info)->loaded;
8466 loaded != NULL;
8467 loaded = loaded->next)
8469 bfd *input;
8470 Elf_Internal_Shdr *hdr;
8471 bfd_size_type symcount;
8472 bfd_size_type extsymcount;
8473 bfd_size_type extsymoff;
8474 Elf_Internal_Shdr *versymhdr;
8475 Elf_Internal_Sym *isym;
8476 Elf_Internal_Sym *isymend;
8477 Elf_Internal_Sym *isymbuf;
8478 Elf_External_Versym *ever;
8479 Elf_External_Versym *extversym;
8481 input = loaded->abfd;
8483 /* We check each DSO for a possible hidden versioned definition. */
8484 if (input == abfd
8485 || (input->flags & DYNAMIC) == 0
8486 || elf_dynversym (input) == 0)
8487 continue;
8489 hdr = &elf_tdata (input)->dynsymtab_hdr;
8491 symcount = hdr->sh_size / bed->s->sizeof_sym;
8492 if (elf_bad_symtab (input))
8494 extsymcount = symcount;
8495 extsymoff = 0;
8497 else
8499 extsymcount = symcount - hdr->sh_info;
8500 extsymoff = hdr->sh_info;
8503 if (extsymcount == 0)
8504 continue;
8506 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
8507 NULL, NULL, NULL);
8508 if (isymbuf == NULL)
8509 return FALSE;
8511 /* Read in any version definitions. */
8512 versymhdr = &elf_tdata (input)->dynversym_hdr;
8513 extversym = (Elf_External_Versym *) bfd_malloc (versymhdr->sh_size);
8514 if (extversym == NULL)
8515 goto error_ret;
8517 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
8518 || (bfd_bread (extversym, versymhdr->sh_size, input)
8519 != versymhdr->sh_size))
8521 free (extversym);
8522 error_ret:
8523 free (isymbuf);
8524 return FALSE;
8527 ever = extversym + extsymoff;
8528 isymend = isymbuf + extsymcount;
8529 for (isym = isymbuf; isym < isymend; isym++, ever++)
8531 const char *name;
8532 Elf_Internal_Versym iver;
8533 unsigned short version_index;
8535 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
8536 || isym->st_shndx == SHN_UNDEF)
8537 continue;
8539 name = bfd_elf_string_from_elf_section (input,
8540 hdr->sh_link,
8541 isym->st_name);
8542 if (strcmp (name, h->root.root.string) != 0)
8543 continue;
8545 _bfd_elf_swap_versym_in (input, ever, &iver);
8547 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
8548 && !(h->def_regular
8549 && h->forced_local))
8551 /* If we have a non-hidden versioned sym, then it should
8552 have provided a definition for the undefined sym unless
8553 it is defined in a non-shared object and forced local.
8555 abort ();
8558 version_index = iver.vs_vers & VERSYM_VERSION;
8559 if (version_index == 1 || version_index == 2)
8561 /* This is the base or first version. We can use it. */
8562 free (extversym);
8563 free (isymbuf);
8564 return TRUE;
8568 free (extversym);
8569 free (isymbuf);
8572 return FALSE;
8575 /* Add an external symbol to the symbol table. This is called from
8576 the hash table traversal routine. When generating a shared object,
8577 we go through the symbol table twice. The first time we output
8578 anything that might have been forced to local scope in a version
8579 script. The second time we output the symbols that are still
8580 global symbols. */
8582 static bfd_boolean
8583 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
8585 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
8586 struct elf_final_link_info *finfo = eoinfo->finfo;
8587 bfd_boolean strip;
8588 Elf_Internal_Sym sym;
8589 asection *input_sec;
8590 const struct elf_backend_data *bed;
8591 long indx;
8592 int ret;
8594 if (h->root.type == bfd_link_hash_warning)
8596 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8597 if (h->root.type == bfd_link_hash_new)
8598 return TRUE;
8601 /* Decide whether to output this symbol in this pass. */
8602 if (eoinfo->localsyms)
8604 if (!h->forced_local)
8605 return TRUE;
8607 else
8609 if (h->forced_local)
8610 return TRUE;
8613 bed = get_elf_backend_data (finfo->output_bfd);
8615 if (h->root.type == bfd_link_hash_undefined)
8617 /* If we have an undefined symbol reference here then it must have
8618 come from a shared library that is being linked in. (Undefined
8619 references in regular files have already been handled unless
8620 they are in unreferenced sections which are removed by garbage
8621 collection). */
8622 bfd_boolean ignore_undef = FALSE;
8624 /* Some symbols may be special in that the fact that they're
8625 undefined can be safely ignored - let backend determine that. */
8626 if (bed->elf_backend_ignore_undef_symbol)
8627 ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
8629 /* If we are reporting errors for this situation then do so now. */
8630 if (ignore_undef == FALSE
8631 && h->ref_dynamic
8632 && (!h->ref_regular || finfo->info->gc_sections)
8633 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
8634 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
8636 if (! (finfo->info->callbacks->undefined_symbol
8637 (finfo->info, h->root.root.string,
8638 h->ref_regular ? NULL : h->root.u.undef.abfd,
8639 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
8641 eoinfo->failed = TRUE;
8642 return FALSE;
8647 /* We should also warn if a forced local symbol is referenced from
8648 shared libraries. */
8649 if (! finfo->info->relocatable
8650 && (! finfo->info->shared)
8651 && h->forced_local
8652 && h->ref_dynamic
8653 && !h->dynamic_def
8654 && !h->dynamic_weak
8655 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
8657 (*_bfd_error_handler)
8658 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
8659 finfo->output_bfd,
8660 h->root.u.def.section == bfd_abs_section_ptr
8661 ? finfo->output_bfd : h->root.u.def.section->owner,
8662 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
8663 ? "internal"
8664 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
8665 ? "hidden" : "local",
8666 h->root.root.string);
8667 eoinfo->failed = TRUE;
8668 return FALSE;
8671 /* We don't want to output symbols that have never been mentioned by
8672 a regular file, or that we have been told to strip. However, if
8673 h->indx is set to -2, the symbol is used by a reloc and we must
8674 output it. */
8675 if (h->indx == -2)
8676 strip = FALSE;
8677 else if ((h->def_dynamic
8678 || h->ref_dynamic
8679 || h->root.type == bfd_link_hash_new)
8680 && !h->def_regular
8681 && !h->ref_regular)
8682 strip = TRUE;
8683 else if (finfo->info->strip == strip_all)
8684 strip = TRUE;
8685 else if (finfo->info->strip == strip_some
8686 && bfd_hash_lookup (finfo->info->keep_hash,
8687 h->root.root.string, FALSE, FALSE) == NULL)
8688 strip = TRUE;
8689 else if (finfo->info->strip_discarded
8690 && (h->root.type == bfd_link_hash_defined
8691 || h->root.type == bfd_link_hash_defweak)
8692 && elf_discarded_section (h->root.u.def.section))
8693 strip = TRUE;
8694 else
8695 strip = FALSE;
8697 /* If we're stripping it, and it's not a dynamic symbol, there's
8698 nothing else to do unless it is a forced local symbol or a
8699 STT_GNU_IFUNC symbol. */
8700 if (strip
8701 && h->dynindx == -1
8702 && h->type != STT_GNU_IFUNC
8703 && !h->forced_local)
8704 return TRUE;
8706 sym.st_value = 0;
8707 sym.st_size = h->size;
8708 sym.st_other = h->other;
8709 if (h->forced_local)
8711 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
8712 /* Turn off visibility on local symbol. */
8713 sym.st_other &= ~ELF_ST_VISIBILITY (-1);
8715 else if (h->unique_global)
8716 sym.st_info = ELF_ST_INFO (STB_GNU_UNIQUE, h->type);
8717 else if (h->root.type == bfd_link_hash_undefweak
8718 || h->root.type == bfd_link_hash_defweak)
8719 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
8720 else
8721 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
8723 switch (h->root.type)
8725 default:
8726 case bfd_link_hash_new:
8727 case bfd_link_hash_warning:
8728 abort ();
8729 return FALSE;
8731 case bfd_link_hash_undefined:
8732 case bfd_link_hash_undefweak:
8733 input_sec = bfd_und_section_ptr;
8734 sym.st_shndx = SHN_UNDEF;
8735 break;
8737 case bfd_link_hash_defined:
8738 case bfd_link_hash_defweak:
8740 input_sec = h->root.u.def.section;
8741 if (input_sec->output_section != NULL)
8743 sym.st_shndx =
8744 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
8745 input_sec->output_section);
8746 if (sym.st_shndx == SHN_BAD)
8748 (*_bfd_error_handler)
8749 (_("%B: could not find output section %A for input section %A"),
8750 finfo->output_bfd, input_sec->output_section, input_sec);
8751 eoinfo->failed = TRUE;
8752 return FALSE;
8755 /* ELF symbols in relocatable files are section relative,
8756 but in nonrelocatable files they are virtual
8757 addresses. */
8758 sym.st_value = h->root.u.def.value + input_sec->output_offset;
8759 if (! finfo->info->relocatable)
8761 sym.st_value += input_sec->output_section->vma;
8762 if (h->type == STT_TLS)
8764 asection *tls_sec = elf_hash_table (finfo->info)->tls_sec;
8765 if (tls_sec != NULL)
8766 sym.st_value -= tls_sec->vma;
8767 else
8769 /* The TLS section may have been garbage collected. */
8770 BFD_ASSERT (finfo->info->gc_sections
8771 && !input_sec->gc_mark);
8776 else
8778 BFD_ASSERT (input_sec->owner == NULL
8779 || (input_sec->owner->flags & DYNAMIC) != 0);
8780 sym.st_shndx = SHN_UNDEF;
8781 input_sec = bfd_und_section_ptr;
8784 break;
8786 case bfd_link_hash_common:
8787 input_sec = h->root.u.c.p->section;
8788 sym.st_shndx = bed->common_section_index (input_sec);
8789 sym.st_value = 1 << h->root.u.c.p->alignment_power;
8790 break;
8792 case bfd_link_hash_indirect:
8793 /* These symbols are created by symbol versioning. They point
8794 to the decorated version of the name. For example, if the
8795 symbol foo@@GNU_1.2 is the default, which should be used when
8796 foo is used with no version, then we add an indirect symbol
8797 foo which points to foo@@GNU_1.2. We ignore these symbols,
8798 since the indirected symbol is already in the hash table. */
8799 return TRUE;
8802 /* Give the processor backend a chance to tweak the symbol value,
8803 and also to finish up anything that needs to be done for this
8804 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
8805 forced local syms when non-shared is due to a historical quirk.
8806 STT_GNU_IFUNC symbol must go through PLT. */
8807 if ((h->type == STT_GNU_IFUNC
8808 && h->def_regular
8809 && !finfo->info->relocatable)
8810 || ((h->dynindx != -1
8811 || h->forced_local)
8812 && ((finfo->info->shared
8813 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
8814 || h->root.type != bfd_link_hash_undefweak))
8815 || !h->forced_local)
8816 && elf_hash_table (finfo->info)->dynamic_sections_created))
8818 if (! ((*bed->elf_backend_finish_dynamic_symbol)
8819 (finfo->output_bfd, finfo->info, h, &sym)))
8821 eoinfo->failed = TRUE;
8822 return FALSE;
8826 /* If we are marking the symbol as undefined, and there are no
8827 non-weak references to this symbol from a regular object, then
8828 mark the symbol as weak undefined; if there are non-weak
8829 references, mark the symbol as strong. We can't do this earlier,
8830 because it might not be marked as undefined until the
8831 finish_dynamic_symbol routine gets through with it. */
8832 if (sym.st_shndx == SHN_UNDEF
8833 && h->ref_regular
8834 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
8835 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
8837 int bindtype;
8838 unsigned int type = ELF_ST_TYPE (sym.st_info);
8840 /* Turn an undefined IFUNC symbol into a normal FUNC symbol. */
8841 if (type == STT_GNU_IFUNC)
8842 type = STT_FUNC;
8844 if (h->ref_regular_nonweak)
8845 bindtype = STB_GLOBAL;
8846 else
8847 bindtype = STB_WEAK;
8848 sym.st_info = ELF_ST_INFO (bindtype, type);
8851 /* If this is a symbol defined in a dynamic library, don't use the
8852 symbol size from the dynamic library. Relinking an executable
8853 against a new library may introduce gratuitous changes in the
8854 executable's symbols if we keep the size. */
8855 if (sym.st_shndx == SHN_UNDEF
8856 && !h->def_regular
8857 && h->def_dynamic)
8858 sym.st_size = 0;
8860 /* If a non-weak symbol with non-default visibility is not defined
8861 locally, it is a fatal error. */
8862 if (! finfo->info->relocatable
8863 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
8864 && ELF_ST_BIND (sym.st_info) != STB_WEAK
8865 && h->root.type == bfd_link_hash_undefined
8866 && !h->def_regular)
8868 (*_bfd_error_handler)
8869 (_("%B: %s symbol `%s' isn't defined"),
8870 finfo->output_bfd,
8871 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
8872 ? "protected"
8873 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
8874 ? "internal" : "hidden",
8875 h->root.root.string);
8876 eoinfo->failed = TRUE;
8877 return FALSE;
8880 /* If this symbol should be put in the .dynsym section, then put it
8881 there now. We already know the symbol index. We also fill in
8882 the entry in the .hash section. */
8883 if (h->dynindx != -1
8884 && elf_hash_table (finfo->info)->dynamic_sections_created)
8886 bfd_byte *esym;
8888 sym.st_name = h->dynstr_index;
8889 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
8890 if (! check_dynsym (finfo->output_bfd, &sym))
8892 eoinfo->failed = TRUE;
8893 return FALSE;
8895 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
8897 if (finfo->hash_sec != NULL)
8899 size_t hash_entry_size;
8900 bfd_byte *bucketpos;
8901 bfd_vma chain;
8902 size_t bucketcount;
8903 size_t bucket;
8905 bucketcount = elf_hash_table (finfo->info)->bucketcount;
8906 bucket = h->u.elf_hash_value % bucketcount;
8908 hash_entry_size
8909 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
8910 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
8911 + (bucket + 2) * hash_entry_size);
8912 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
8913 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
8914 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
8915 ((bfd_byte *) finfo->hash_sec->contents
8916 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
8919 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
8921 Elf_Internal_Versym iversym;
8922 Elf_External_Versym *eversym;
8924 if (!h->def_regular)
8926 if (h->verinfo.verdef == NULL)
8927 iversym.vs_vers = 0;
8928 else
8929 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
8931 else
8933 if (h->verinfo.vertree == NULL)
8934 iversym.vs_vers = 1;
8935 else
8936 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
8937 if (finfo->info->create_default_symver)
8938 iversym.vs_vers++;
8941 if (h->hidden)
8942 iversym.vs_vers |= VERSYM_HIDDEN;
8944 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
8945 eversym += h->dynindx;
8946 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
8950 /* If we're stripping it, then it was just a dynamic symbol, and
8951 there's nothing else to do. */
8952 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
8953 return TRUE;
8955 indx = bfd_get_symcount (finfo->output_bfd);
8956 ret = elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h);
8957 if (ret == 0)
8959 eoinfo->failed = TRUE;
8960 return FALSE;
8962 else if (ret == 1)
8963 h->indx = indx;
8964 else if (h->indx == -2)
8965 abort();
8967 return TRUE;
8970 /* Return TRUE if special handling is done for relocs in SEC against
8971 symbols defined in discarded sections. */
8973 static bfd_boolean
8974 elf_section_ignore_discarded_relocs (asection *sec)
8976 const struct elf_backend_data *bed;
8978 switch (sec->sec_info_type)
8980 case ELF_INFO_TYPE_STABS:
8981 case ELF_INFO_TYPE_EH_FRAME:
8982 return TRUE;
8983 default:
8984 break;
8987 bed = get_elf_backend_data (sec->owner);
8988 if (bed->elf_backend_ignore_discarded_relocs != NULL
8989 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
8990 return TRUE;
8992 return FALSE;
8995 /* Return a mask saying how ld should treat relocations in SEC against
8996 symbols defined in discarded sections. If this function returns
8997 COMPLAIN set, ld will issue a warning message. If this function
8998 returns PRETEND set, and the discarded section was link-once and the
8999 same size as the kept link-once section, ld will pretend that the
9000 symbol was actually defined in the kept section. Otherwise ld will
9001 zero the reloc (at least that is the intent, but some cooperation by
9002 the target dependent code is needed, particularly for REL targets). */
9004 unsigned int
9005 _bfd_elf_default_action_discarded (asection *sec)
9007 if (sec->flags & SEC_DEBUGGING)
9008 return PRETEND;
9010 if (strcmp (".eh_frame", sec->name) == 0)
9011 return 0;
9013 if (strcmp (".gcc_except_table", sec->name) == 0)
9014 return 0;
9016 return COMPLAIN | PRETEND;
9019 /* Find a match between a section and a member of a section group. */
9021 static asection *
9022 match_group_member (asection *sec, asection *group,
9023 struct bfd_link_info *info)
9025 asection *first = elf_next_in_group (group);
9026 asection *s = first;
9028 while (s != NULL)
9030 if (bfd_elf_match_symbols_in_sections (s, sec, info))
9031 return s;
9033 s = elf_next_in_group (s);
9034 if (s == first)
9035 break;
9038 return NULL;
9041 /* Check if the kept section of a discarded section SEC can be used
9042 to replace it. Return the replacement if it is OK. Otherwise return
9043 NULL. */
9045 asection *
9046 _bfd_elf_check_kept_section (asection *sec, struct bfd_link_info *info)
9048 asection *kept;
9050 kept = sec->kept_section;
9051 if (kept != NULL)
9053 if ((kept->flags & SEC_GROUP) != 0)
9054 kept = match_group_member (sec, kept, info);
9055 if (kept != NULL
9056 && ((sec->rawsize != 0 ? sec->rawsize : sec->size)
9057 != (kept->rawsize != 0 ? kept->rawsize : kept->size)))
9058 kept = NULL;
9059 sec->kept_section = kept;
9061 return kept;
9064 /* Link an input file into the linker output file. This function
9065 handles all the sections and relocations of the input file at once.
9066 This is so that we only have to read the local symbols once, and
9067 don't have to keep them in memory. */
9069 static bfd_boolean
9070 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
9072 int (*relocate_section)
9073 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
9074 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
9075 bfd *output_bfd;
9076 Elf_Internal_Shdr *symtab_hdr;
9077 size_t locsymcount;
9078 size_t extsymoff;
9079 Elf_Internal_Sym *isymbuf;
9080 Elf_Internal_Sym *isym;
9081 Elf_Internal_Sym *isymend;
9082 long *pindex;
9083 asection **ppsection;
9084 asection *o;
9085 const struct elf_backend_data *bed;
9086 struct elf_link_hash_entry **sym_hashes;
9088 output_bfd = finfo->output_bfd;
9089 bed = get_elf_backend_data (output_bfd);
9090 relocate_section = bed->elf_backend_relocate_section;
9092 /* If this is a dynamic object, we don't want to do anything here:
9093 we don't want the local symbols, and we don't want the section
9094 contents. */
9095 if ((input_bfd->flags & DYNAMIC) != 0)
9096 return TRUE;
9098 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
9099 if (elf_bad_symtab (input_bfd))
9101 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9102 extsymoff = 0;
9104 else
9106 locsymcount = symtab_hdr->sh_info;
9107 extsymoff = symtab_hdr->sh_info;
9110 /* Read the local symbols. */
9111 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
9112 if (isymbuf == NULL && locsymcount != 0)
9114 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
9115 finfo->internal_syms,
9116 finfo->external_syms,
9117 finfo->locsym_shndx);
9118 if (isymbuf == NULL)
9119 return FALSE;
9122 /* Find local symbol sections and adjust values of symbols in
9123 SEC_MERGE sections. Write out those local symbols we know are
9124 going into the output file. */
9125 isymend = isymbuf + locsymcount;
9126 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
9127 isym < isymend;
9128 isym++, pindex++, ppsection++)
9130 asection *isec;
9131 const char *name;
9132 Elf_Internal_Sym osym;
9133 long indx;
9134 int ret;
9136 *pindex = -1;
9138 if (elf_bad_symtab (input_bfd))
9140 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
9142 *ppsection = NULL;
9143 continue;
9147 if (isym->st_shndx == SHN_UNDEF)
9148 isec = bfd_und_section_ptr;
9149 else if (isym->st_shndx == SHN_ABS)
9150 isec = bfd_abs_section_ptr;
9151 else if (isym->st_shndx == SHN_COMMON)
9152 isec = bfd_com_section_ptr;
9153 else
9155 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
9156 if (isec == NULL)
9158 /* Don't attempt to output symbols with st_shnx in the
9159 reserved range other than SHN_ABS and SHN_COMMON. */
9160 *ppsection = NULL;
9161 continue;
9163 else if (isec->sec_info_type == ELF_INFO_TYPE_MERGE
9164 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
9165 isym->st_value =
9166 _bfd_merged_section_offset (output_bfd, &isec,
9167 elf_section_data (isec)->sec_info,
9168 isym->st_value);
9171 *ppsection = isec;
9173 /* Don't output the first, undefined, symbol. */
9174 if (ppsection == finfo->sections)
9175 continue;
9177 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
9179 /* We never output section symbols. Instead, we use the
9180 section symbol of the corresponding section in the output
9181 file. */
9182 continue;
9185 /* If we are stripping all symbols, we don't want to output this
9186 one. */
9187 if (finfo->info->strip == strip_all)
9188 continue;
9190 /* If we are discarding all local symbols, we don't want to
9191 output this one. If we are generating a relocatable output
9192 file, then some of the local symbols may be required by
9193 relocs; we output them below as we discover that they are
9194 needed. */
9195 if (finfo->info->discard == discard_all)
9196 continue;
9198 /* If this symbol is defined in a section which we are
9199 discarding, we don't need to keep it. */
9200 if (isym->st_shndx != SHN_UNDEF
9201 && isym->st_shndx < SHN_LORESERVE
9202 && bfd_section_removed_from_list (output_bfd,
9203 isec->output_section))
9204 continue;
9206 /* Get the name of the symbol. */
9207 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
9208 isym->st_name);
9209 if (name == NULL)
9210 return FALSE;
9212 /* See if we are discarding symbols with this name. */
9213 if ((finfo->info->strip == strip_some
9214 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
9215 == NULL))
9216 || (((finfo->info->discard == discard_sec_merge
9217 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
9218 || finfo->info->discard == discard_l)
9219 && bfd_is_local_label_name (input_bfd, name)))
9220 continue;
9222 osym = *isym;
9224 /* Adjust the section index for the output file. */
9225 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
9226 isec->output_section);
9227 if (osym.st_shndx == SHN_BAD)
9228 return FALSE;
9230 /* ELF symbols in relocatable files are section relative, but
9231 in executable files they are virtual addresses. Note that
9232 this code assumes that all ELF sections have an associated
9233 BFD section with a reasonable value for output_offset; below
9234 we assume that they also have a reasonable value for
9235 output_section. Any special sections must be set up to meet
9236 these requirements. */
9237 osym.st_value += isec->output_offset;
9238 if (! finfo->info->relocatable)
9240 osym.st_value += isec->output_section->vma;
9241 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
9243 /* STT_TLS symbols are relative to PT_TLS segment base. */
9244 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
9245 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
9249 indx = bfd_get_symcount (output_bfd);
9250 ret = elf_link_output_sym (finfo, name, &osym, isec, NULL);
9251 if (ret == 0)
9252 return FALSE;
9253 else if (ret == 1)
9254 *pindex = indx;
9257 /* Relocate the contents of each section. */
9258 sym_hashes = elf_sym_hashes (input_bfd);
9259 for (o = input_bfd->sections; o != NULL; o = o->next)
9261 bfd_byte *contents;
9263 if (! o->linker_mark)
9265 /* This section was omitted from the link. */
9266 continue;
9269 if (finfo->info->relocatable
9270 && (o->flags & (SEC_LINKER_CREATED | SEC_GROUP)) == SEC_GROUP)
9272 /* Deal with the group signature symbol. */
9273 struct bfd_elf_section_data *sec_data = elf_section_data (o);
9274 unsigned long symndx = sec_data->this_hdr.sh_info;
9275 asection *osec = o->output_section;
9277 if (symndx >= locsymcount
9278 || (elf_bad_symtab (input_bfd)
9279 && finfo->sections[symndx] == NULL))
9281 struct elf_link_hash_entry *h = sym_hashes[symndx - extsymoff];
9282 while (h->root.type == bfd_link_hash_indirect
9283 || h->root.type == bfd_link_hash_warning)
9284 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9285 /* Arrange for symbol to be output. */
9286 h->indx = -2;
9287 elf_section_data (osec)->this_hdr.sh_info = -2;
9289 else if (ELF_ST_TYPE (isymbuf[symndx].st_info) == STT_SECTION)
9291 /* We'll use the output section target_index. */
9292 asection *sec = finfo->sections[symndx]->output_section;
9293 elf_section_data (osec)->this_hdr.sh_info = sec->target_index;
9295 else
9297 if (finfo->indices[symndx] == -1)
9299 /* Otherwise output the local symbol now. */
9300 Elf_Internal_Sym sym = isymbuf[symndx];
9301 asection *sec = finfo->sections[symndx]->output_section;
9302 const char *name;
9303 long indx;
9304 int ret;
9306 name = bfd_elf_string_from_elf_section (input_bfd,
9307 symtab_hdr->sh_link,
9308 sym.st_name);
9309 if (name == NULL)
9310 return FALSE;
9312 sym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
9313 sec);
9314 if (sym.st_shndx == SHN_BAD)
9315 return FALSE;
9317 sym.st_value += o->output_offset;
9319 indx = bfd_get_symcount (output_bfd);
9320 ret = elf_link_output_sym (finfo, name, &sym, o, NULL);
9321 if (ret == 0)
9322 return FALSE;
9323 else if (ret == 1)
9324 finfo->indices[symndx] = indx;
9325 else
9326 abort ();
9328 elf_section_data (osec)->this_hdr.sh_info
9329 = finfo->indices[symndx];
9333 if ((o->flags & SEC_HAS_CONTENTS) == 0
9334 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
9335 continue;
9337 if ((o->flags & SEC_LINKER_CREATED) != 0)
9339 /* Section was created by _bfd_elf_link_create_dynamic_sections
9340 or somesuch. */
9341 continue;
9344 /* Get the contents of the section. They have been cached by a
9345 relaxation routine. Note that o is a section in an input
9346 file, so the contents field will not have been set by any of
9347 the routines which work on output files. */
9348 if (elf_section_data (o)->this_hdr.contents != NULL)
9349 contents = elf_section_data (o)->this_hdr.contents;
9350 else
9352 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
9354 contents = finfo->contents;
9355 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
9356 return FALSE;
9359 if ((o->flags & SEC_RELOC) != 0)
9361 Elf_Internal_Rela *internal_relocs;
9362 Elf_Internal_Rela *rel, *relend;
9363 bfd_vma r_type_mask;
9364 int r_sym_shift;
9365 int action_discarded;
9366 int ret;
9368 /* Get the swapped relocs. */
9369 internal_relocs
9370 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
9371 finfo->internal_relocs, FALSE);
9372 if (internal_relocs == NULL
9373 && o->reloc_count > 0)
9374 return FALSE;
9376 if (bed->s->arch_size == 32)
9378 r_type_mask = 0xff;
9379 r_sym_shift = 8;
9381 else
9383 r_type_mask = 0xffffffff;
9384 r_sym_shift = 32;
9387 action_discarded = -1;
9388 if (!elf_section_ignore_discarded_relocs (o))
9389 action_discarded = (*bed->action_discarded) (o);
9391 /* Run through the relocs evaluating complex reloc symbols and
9392 looking for relocs against symbols from discarded sections
9393 or section symbols from removed link-once sections.
9394 Complain about relocs against discarded sections. Zero
9395 relocs against removed link-once sections. */
9397 rel = internal_relocs;
9398 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
9399 for ( ; rel < relend; rel++)
9401 unsigned long r_symndx = rel->r_info >> r_sym_shift;
9402 unsigned int s_type;
9403 asection **ps, *sec;
9404 struct elf_link_hash_entry *h = NULL;
9405 const char *sym_name;
9407 if (r_symndx == STN_UNDEF)
9408 continue;
9410 if (r_symndx >= locsymcount
9411 || (elf_bad_symtab (input_bfd)
9412 && finfo->sections[r_symndx] == NULL))
9414 h = sym_hashes[r_symndx - extsymoff];
9416 /* Badly formatted input files can contain relocs that
9417 reference non-existant symbols. Check here so that
9418 we do not seg fault. */
9419 if (h == NULL)
9421 char buffer [32];
9423 sprintf_vma (buffer, rel->r_info);
9424 (*_bfd_error_handler)
9425 (_("error: %B contains a reloc (0x%s) for section %A "
9426 "that references a non-existent global symbol"),
9427 input_bfd, o, buffer);
9428 bfd_set_error (bfd_error_bad_value);
9429 return FALSE;
9432 while (h->root.type == bfd_link_hash_indirect
9433 || h->root.type == bfd_link_hash_warning)
9434 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9436 s_type = h->type;
9438 ps = NULL;
9439 if (h->root.type == bfd_link_hash_defined
9440 || h->root.type == bfd_link_hash_defweak)
9441 ps = &h->root.u.def.section;
9443 sym_name = h->root.root.string;
9445 else
9447 Elf_Internal_Sym *sym = isymbuf + r_symndx;
9449 s_type = ELF_ST_TYPE (sym->st_info);
9450 ps = &finfo->sections[r_symndx];
9451 sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr,
9452 sym, *ps);
9455 if ((s_type == STT_RELC || s_type == STT_SRELC)
9456 && !finfo->info->relocatable)
9458 bfd_vma val;
9459 bfd_vma dot = (rel->r_offset
9460 + o->output_offset + o->output_section->vma);
9461 #ifdef DEBUG
9462 printf ("Encountered a complex symbol!");
9463 printf (" (input_bfd %s, section %s, reloc %ld\n",
9464 input_bfd->filename, o->name, rel - internal_relocs);
9465 printf (" symbol: idx %8.8lx, name %s\n",
9466 r_symndx, sym_name);
9467 printf (" reloc : info %8.8lx, addr %8.8lx\n",
9468 (unsigned long) rel->r_info,
9469 (unsigned long) rel->r_offset);
9470 #endif
9471 if (!eval_symbol (&val, &sym_name, input_bfd, finfo, dot,
9472 isymbuf, locsymcount, s_type == STT_SRELC))
9473 return FALSE;
9475 /* Symbol evaluated OK. Update to absolute value. */
9476 set_symbol_value (input_bfd, isymbuf, locsymcount,
9477 r_symndx, val);
9478 continue;
9481 if (action_discarded != -1 && ps != NULL)
9483 /* Complain if the definition comes from a
9484 discarded section. */
9485 if ((sec = *ps) != NULL && elf_discarded_section (sec))
9487 BFD_ASSERT (r_symndx != 0);
9488 if (action_discarded & COMPLAIN)
9489 (*finfo->info->callbacks->einfo)
9490 (_("%X`%s' referenced in section `%A' of %B: "
9491 "defined in discarded section `%A' of %B\n"),
9492 sym_name, o, input_bfd, sec, sec->owner);
9494 /* Try to do the best we can to support buggy old
9495 versions of gcc. Pretend that the symbol is
9496 really defined in the kept linkonce section.
9497 FIXME: This is quite broken. Modifying the
9498 symbol here means we will be changing all later
9499 uses of the symbol, not just in this section. */
9500 if (action_discarded & PRETEND)
9502 asection *kept;
9504 kept = _bfd_elf_check_kept_section (sec,
9505 finfo->info);
9506 if (kept != NULL)
9508 *ps = kept;
9509 continue;
9516 /* Relocate the section by invoking a back end routine.
9518 The back end routine is responsible for adjusting the
9519 section contents as necessary, and (if using Rela relocs
9520 and generating a relocatable output file) adjusting the
9521 reloc addend as necessary.
9523 The back end routine does not have to worry about setting
9524 the reloc address or the reloc symbol index.
9526 The back end routine is given a pointer to the swapped in
9527 internal symbols, and can access the hash table entries
9528 for the external symbols via elf_sym_hashes (input_bfd).
9530 When generating relocatable output, the back end routine
9531 must handle STB_LOCAL/STT_SECTION symbols specially. The
9532 output symbol is going to be a section symbol
9533 corresponding to the output section, which will require
9534 the addend to be adjusted. */
9536 ret = (*relocate_section) (output_bfd, finfo->info,
9537 input_bfd, o, contents,
9538 internal_relocs,
9539 isymbuf,
9540 finfo->sections);
9541 if (!ret)
9542 return FALSE;
9544 if (ret == 2
9545 || finfo->info->relocatable
9546 || finfo->info->emitrelocations)
9548 Elf_Internal_Rela *irela;
9549 Elf_Internal_Rela *irelaend;
9550 bfd_vma last_offset;
9551 struct elf_link_hash_entry **rel_hash;
9552 struct elf_link_hash_entry **rel_hash_list;
9553 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
9554 unsigned int next_erel;
9555 bfd_boolean rela_normal;
9557 input_rel_hdr = &elf_section_data (o)->rel_hdr;
9558 rela_normal = (bed->rela_normal
9559 && (input_rel_hdr->sh_entsize
9560 == bed->s->sizeof_rela));
9562 /* Adjust the reloc addresses and symbol indices. */
9564 irela = internal_relocs;
9565 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
9566 rel_hash = (elf_section_data (o->output_section)->rel_hashes
9567 + elf_section_data (o->output_section)->rel_count
9568 + elf_section_data (o->output_section)->rel_count2);
9569 rel_hash_list = rel_hash;
9570 last_offset = o->output_offset;
9571 if (!finfo->info->relocatable)
9572 last_offset += o->output_section->vma;
9573 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
9575 unsigned long r_symndx;
9576 asection *sec;
9577 Elf_Internal_Sym sym;
9579 if (next_erel == bed->s->int_rels_per_ext_rel)
9581 rel_hash++;
9582 next_erel = 0;
9585 irela->r_offset = _bfd_elf_section_offset (output_bfd,
9586 finfo->info, o,
9587 irela->r_offset);
9588 if (irela->r_offset >= (bfd_vma) -2)
9590 /* This is a reloc for a deleted entry or somesuch.
9591 Turn it into an R_*_NONE reloc, at the same
9592 offset as the last reloc. elf_eh_frame.c and
9593 bfd_elf_discard_info rely on reloc offsets
9594 being ordered. */
9595 irela->r_offset = last_offset;
9596 irela->r_info = 0;
9597 irela->r_addend = 0;
9598 continue;
9601 irela->r_offset += o->output_offset;
9603 /* Relocs in an executable have to be virtual addresses. */
9604 if (!finfo->info->relocatable)
9605 irela->r_offset += o->output_section->vma;
9607 last_offset = irela->r_offset;
9609 r_symndx = irela->r_info >> r_sym_shift;
9610 if (r_symndx == STN_UNDEF)
9611 continue;
9613 if (r_symndx >= locsymcount
9614 || (elf_bad_symtab (input_bfd)
9615 && finfo->sections[r_symndx] == NULL))
9617 struct elf_link_hash_entry *rh;
9618 unsigned long indx;
9620 /* This is a reloc against a global symbol. We
9621 have not yet output all the local symbols, so
9622 we do not know the symbol index of any global
9623 symbol. We set the rel_hash entry for this
9624 reloc to point to the global hash table entry
9625 for this symbol. The symbol index is then
9626 set at the end of bfd_elf_final_link. */
9627 indx = r_symndx - extsymoff;
9628 rh = elf_sym_hashes (input_bfd)[indx];
9629 while (rh->root.type == bfd_link_hash_indirect
9630 || rh->root.type == bfd_link_hash_warning)
9631 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
9633 /* Setting the index to -2 tells
9634 elf_link_output_extsym that this symbol is
9635 used by a reloc. */
9636 BFD_ASSERT (rh->indx < 0);
9637 rh->indx = -2;
9639 *rel_hash = rh;
9641 continue;
9644 /* This is a reloc against a local symbol. */
9646 *rel_hash = NULL;
9647 sym = isymbuf[r_symndx];
9648 sec = finfo->sections[r_symndx];
9649 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
9651 /* I suppose the backend ought to fill in the
9652 section of any STT_SECTION symbol against a
9653 processor specific section. */
9654 r_symndx = 0;
9655 if (bfd_is_abs_section (sec))
9657 else if (sec == NULL || sec->owner == NULL)
9659 bfd_set_error (bfd_error_bad_value);
9660 return FALSE;
9662 else
9664 asection *osec = sec->output_section;
9666 /* If we have discarded a section, the output
9667 section will be the absolute section. In
9668 case of discarded SEC_MERGE sections, use
9669 the kept section. relocate_section should
9670 have already handled discarded linkonce
9671 sections. */
9672 if (bfd_is_abs_section (osec)
9673 && sec->kept_section != NULL
9674 && sec->kept_section->output_section != NULL)
9676 osec = sec->kept_section->output_section;
9677 irela->r_addend -= osec->vma;
9680 if (!bfd_is_abs_section (osec))
9682 r_symndx = osec->target_index;
9683 if (r_symndx == 0)
9685 struct elf_link_hash_table *htab;
9686 asection *oi;
9688 htab = elf_hash_table (finfo->info);
9689 oi = htab->text_index_section;
9690 if ((osec->flags & SEC_READONLY) == 0
9691 && htab->data_index_section != NULL)
9692 oi = htab->data_index_section;
9694 if (oi != NULL)
9696 irela->r_addend += osec->vma - oi->vma;
9697 r_symndx = oi->target_index;
9701 BFD_ASSERT (r_symndx != 0);
9705 /* Adjust the addend according to where the
9706 section winds up in the output section. */
9707 if (rela_normal)
9708 irela->r_addend += sec->output_offset;
9710 else
9712 if (finfo->indices[r_symndx] == -1)
9714 unsigned long shlink;
9715 const char *name;
9716 asection *osec;
9717 long indx;
9719 if (finfo->info->strip == strip_all)
9721 /* You can't do ld -r -s. */
9722 bfd_set_error (bfd_error_invalid_operation);
9723 return FALSE;
9726 /* This symbol was skipped earlier, but
9727 since it is needed by a reloc, we
9728 must output it now. */
9729 shlink = symtab_hdr->sh_link;
9730 name = (bfd_elf_string_from_elf_section
9731 (input_bfd, shlink, sym.st_name));
9732 if (name == NULL)
9733 return FALSE;
9735 osec = sec->output_section;
9736 sym.st_shndx =
9737 _bfd_elf_section_from_bfd_section (output_bfd,
9738 osec);
9739 if (sym.st_shndx == SHN_BAD)
9740 return FALSE;
9742 sym.st_value += sec->output_offset;
9743 if (! finfo->info->relocatable)
9745 sym.st_value += osec->vma;
9746 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
9748 /* STT_TLS symbols are relative to PT_TLS
9749 segment base. */
9750 BFD_ASSERT (elf_hash_table (finfo->info)
9751 ->tls_sec != NULL);
9752 sym.st_value -= (elf_hash_table (finfo->info)
9753 ->tls_sec->vma);
9757 indx = bfd_get_symcount (output_bfd);
9758 ret = elf_link_output_sym (finfo, name, &sym, sec,
9759 NULL);
9760 if (ret == 0)
9761 return FALSE;
9762 else if (ret == 1)
9763 finfo->indices[r_symndx] = indx;
9764 else
9765 abort ();
9768 r_symndx = finfo->indices[r_symndx];
9771 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
9772 | (irela->r_info & r_type_mask));
9775 /* Swap out the relocs. */
9776 if (input_rel_hdr->sh_size != 0
9777 && !bed->elf_backend_emit_relocs (output_bfd, o,
9778 input_rel_hdr,
9779 internal_relocs,
9780 rel_hash_list))
9781 return FALSE;
9783 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
9784 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
9786 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
9787 * bed->s->int_rels_per_ext_rel);
9788 rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
9789 if (!bed->elf_backend_emit_relocs (output_bfd, o,
9790 input_rel_hdr2,
9791 internal_relocs,
9792 rel_hash_list))
9793 return FALSE;
9798 /* Write out the modified section contents. */
9799 if (bed->elf_backend_write_section
9800 && (*bed->elf_backend_write_section) (output_bfd, finfo->info, o,
9801 contents))
9803 /* Section written out. */
9805 else switch (o->sec_info_type)
9807 case ELF_INFO_TYPE_STABS:
9808 if (! (_bfd_write_section_stabs
9809 (output_bfd,
9810 &elf_hash_table (finfo->info)->stab_info,
9811 o, &elf_section_data (o)->sec_info, contents)))
9812 return FALSE;
9813 break;
9814 case ELF_INFO_TYPE_MERGE:
9815 if (! _bfd_write_merged_section (output_bfd, o,
9816 elf_section_data (o)->sec_info))
9817 return FALSE;
9818 break;
9819 case ELF_INFO_TYPE_EH_FRAME:
9821 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
9822 o, contents))
9823 return FALSE;
9825 break;
9826 default:
9828 /* FIXME: octets_per_byte. */
9829 if (! (o->flags & SEC_EXCLUDE)
9830 && ! (o->output_section->flags & SEC_NEVER_LOAD)
9831 && ! bfd_set_section_contents (output_bfd, o->output_section,
9832 contents,
9833 (file_ptr) o->output_offset,
9834 o->size))
9835 return FALSE;
9837 break;
9841 return TRUE;
9844 /* Generate a reloc when linking an ELF file. This is a reloc
9845 requested by the linker, and does not come from any input file. This
9846 is used to build constructor and destructor tables when linking
9847 with -Ur. */
9849 static bfd_boolean
9850 elf_reloc_link_order (bfd *output_bfd,
9851 struct bfd_link_info *info,
9852 asection *output_section,
9853 struct bfd_link_order *link_order)
9855 reloc_howto_type *howto;
9856 long indx;
9857 bfd_vma offset;
9858 bfd_vma addend;
9859 struct elf_link_hash_entry **rel_hash_ptr;
9860 Elf_Internal_Shdr *rel_hdr;
9861 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
9862 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
9863 bfd_byte *erel;
9864 unsigned int i;
9866 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
9867 if (howto == NULL)
9869 bfd_set_error (bfd_error_bad_value);
9870 return FALSE;
9873 addend = link_order->u.reloc.p->addend;
9875 /* Figure out the symbol index. */
9876 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
9877 + elf_section_data (output_section)->rel_count
9878 + elf_section_data (output_section)->rel_count2);
9879 if (link_order->type == bfd_section_reloc_link_order)
9881 indx = link_order->u.reloc.p->u.section->target_index;
9882 BFD_ASSERT (indx != 0);
9883 *rel_hash_ptr = NULL;
9885 else
9887 struct elf_link_hash_entry *h;
9889 /* Treat a reloc against a defined symbol as though it were
9890 actually against the section. */
9891 h = ((struct elf_link_hash_entry *)
9892 bfd_wrapped_link_hash_lookup (output_bfd, info,
9893 link_order->u.reloc.p->u.name,
9894 FALSE, FALSE, TRUE));
9895 if (h != NULL
9896 && (h->root.type == bfd_link_hash_defined
9897 || h->root.type == bfd_link_hash_defweak))
9899 asection *section;
9901 section = h->root.u.def.section;
9902 indx = section->output_section->target_index;
9903 *rel_hash_ptr = NULL;
9904 /* It seems that we ought to add the symbol value to the
9905 addend here, but in practice it has already been added
9906 because it was passed to constructor_callback. */
9907 addend += section->output_section->vma + section->output_offset;
9909 else if (h != NULL)
9911 /* Setting the index to -2 tells elf_link_output_extsym that
9912 this symbol is used by a reloc. */
9913 h->indx = -2;
9914 *rel_hash_ptr = h;
9915 indx = 0;
9917 else
9919 if (! ((*info->callbacks->unattached_reloc)
9920 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
9921 return FALSE;
9922 indx = 0;
9926 /* If this is an inplace reloc, we must write the addend into the
9927 object file. */
9928 if (howto->partial_inplace && addend != 0)
9930 bfd_size_type size;
9931 bfd_reloc_status_type rstat;
9932 bfd_byte *buf;
9933 bfd_boolean ok;
9934 const char *sym_name;
9936 size = (bfd_size_type) bfd_get_reloc_size (howto);
9937 buf = (bfd_byte *) bfd_zmalloc (size);
9938 if (buf == NULL)
9939 return FALSE;
9940 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
9941 switch (rstat)
9943 case bfd_reloc_ok:
9944 break;
9946 default:
9947 case bfd_reloc_outofrange:
9948 abort ();
9950 case bfd_reloc_overflow:
9951 if (link_order->type == bfd_section_reloc_link_order)
9952 sym_name = bfd_section_name (output_bfd,
9953 link_order->u.reloc.p->u.section);
9954 else
9955 sym_name = link_order->u.reloc.p->u.name;
9956 if (! ((*info->callbacks->reloc_overflow)
9957 (info, NULL, sym_name, howto->name, addend, NULL,
9958 NULL, (bfd_vma) 0)))
9960 free (buf);
9961 return FALSE;
9963 break;
9965 ok = bfd_set_section_contents (output_bfd, output_section, buf,
9966 link_order->offset, size);
9967 free (buf);
9968 if (! ok)
9969 return FALSE;
9972 /* The address of a reloc is relative to the section in a
9973 relocatable file, and is a virtual address in an executable
9974 file. */
9975 offset = link_order->offset;
9976 if (! info->relocatable)
9977 offset += output_section->vma;
9979 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
9981 irel[i].r_offset = offset;
9982 irel[i].r_info = 0;
9983 irel[i].r_addend = 0;
9985 if (bed->s->arch_size == 32)
9986 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
9987 else
9988 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
9990 rel_hdr = &elf_section_data (output_section)->rel_hdr;
9991 erel = rel_hdr->contents;
9992 if (rel_hdr->sh_type == SHT_REL)
9994 erel += (elf_section_data (output_section)->rel_count
9995 * bed->s->sizeof_rel);
9996 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
9998 else
10000 irel[0].r_addend = addend;
10001 erel += (elf_section_data (output_section)->rel_count
10002 * bed->s->sizeof_rela);
10003 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
10006 ++elf_section_data (output_section)->rel_count;
10008 return TRUE;
10012 /* Get the output vma of the section pointed to by the sh_link field. */
10014 static bfd_vma
10015 elf_get_linked_section_vma (struct bfd_link_order *p)
10017 Elf_Internal_Shdr **elf_shdrp;
10018 asection *s;
10019 int elfsec;
10021 s = p->u.indirect.section;
10022 elf_shdrp = elf_elfsections (s->owner);
10023 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
10024 elfsec = elf_shdrp[elfsec]->sh_link;
10025 /* PR 290:
10026 The Intel C compiler generates SHT_IA_64_UNWIND with
10027 SHF_LINK_ORDER. But it doesn't set the sh_link or
10028 sh_info fields. Hence we could get the situation
10029 where elfsec is 0. */
10030 if (elfsec == 0)
10032 const struct elf_backend_data *bed
10033 = get_elf_backend_data (s->owner);
10034 if (bed->link_order_error_handler)
10035 bed->link_order_error_handler
10036 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
10037 return 0;
10039 else
10041 s = elf_shdrp[elfsec]->bfd_section;
10042 return s->output_section->vma + s->output_offset;
10047 /* Compare two sections based on the locations of the sections they are
10048 linked to. Used by elf_fixup_link_order. */
10050 static int
10051 compare_link_order (const void * a, const void * b)
10053 bfd_vma apos;
10054 bfd_vma bpos;
10056 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
10057 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
10058 if (apos < bpos)
10059 return -1;
10060 return apos > bpos;
10064 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
10065 order as their linked sections. Returns false if this could not be done
10066 because an output section includes both ordered and unordered
10067 sections. Ideally we'd do this in the linker proper. */
10069 static bfd_boolean
10070 elf_fixup_link_order (bfd *abfd, asection *o)
10072 int seen_linkorder;
10073 int seen_other;
10074 int n;
10075 struct bfd_link_order *p;
10076 bfd *sub;
10077 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10078 unsigned elfsec;
10079 struct bfd_link_order **sections;
10080 asection *s, *other_sec, *linkorder_sec;
10081 bfd_vma offset;
10083 other_sec = NULL;
10084 linkorder_sec = NULL;
10085 seen_other = 0;
10086 seen_linkorder = 0;
10087 for (p = o->map_head.link_order; p != NULL; p = p->next)
10089 if (p->type == bfd_indirect_link_order)
10091 s = p->u.indirect.section;
10092 sub = s->owner;
10093 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
10094 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass
10095 && (elfsec = _bfd_elf_section_from_bfd_section (sub, s))
10096 && elfsec < elf_numsections (sub)
10097 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER
10098 && elf_elfsections (sub)[elfsec]->sh_link < elf_numsections (sub))
10100 seen_linkorder++;
10101 linkorder_sec = s;
10103 else
10105 seen_other++;
10106 other_sec = s;
10109 else
10110 seen_other++;
10112 if (seen_other && seen_linkorder)
10114 if (other_sec && linkorder_sec)
10115 (*_bfd_error_handler) (_("%A has both ordered [`%A' in %B] and unordered [`%A' in %B] sections"),
10116 o, linkorder_sec,
10117 linkorder_sec->owner, other_sec,
10118 other_sec->owner);
10119 else
10120 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
10122 bfd_set_error (bfd_error_bad_value);
10123 return FALSE;
10127 if (!seen_linkorder)
10128 return TRUE;
10130 sections = (struct bfd_link_order **)
10131 bfd_malloc (seen_linkorder * sizeof (struct bfd_link_order *));
10132 if (sections == NULL)
10133 return FALSE;
10134 seen_linkorder = 0;
10136 for (p = o->map_head.link_order; p != NULL; p = p->next)
10138 sections[seen_linkorder++] = p;
10140 /* Sort the input sections in the order of their linked section. */
10141 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
10142 compare_link_order);
10144 /* Change the offsets of the sections. */
10145 offset = 0;
10146 for (n = 0; n < seen_linkorder; n++)
10148 s = sections[n]->u.indirect.section;
10149 offset &= ~(bfd_vma) 0 << s->alignment_power;
10150 s->output_offset = offset;
10151 sections[n]->offset = offset;
10152 /* FIXME: octets_per_byte. */
10153 offset += sections[n]->size;
10156 free (sections);
10157 return TRUE;
10161 /* Do the final step of an ELF link. */
10163 bfd_boolean
10164 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
10166 bfd_boolean dynamic;
10167 bfd_boolean emit_relocs;
10168 bfd *dynobj;
10169 struct elf_final_link_info finfo;
10170 asection *o;
10171 struct bfd_link_order *p;
10172 bfd *sub;
10173 bfd_size_type max_contents_size;
10174 bfd_size_type max_external_reloc_size;
10175 bfd_size_type max_internal_reloc_count;
10176 bfd_size_type max_sym_count;
10177 bfd_size_type max_sym_shndx_count;
10178 file_ptr off;
10179 Elf_Internal_Sym elfsym;
10180 unsigned int i;
10181 Elf_Internal_Shdr *symtab_hdr;
10182 Elf_Internal_Shdr *symtab_shndx_hdr;
10183 Elf_Internal_Shdr *symstrtab_hdr;
10184 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10185 struct elf_outext_info eoinfo;
10186 bfd_boolean merged;
10187 size_t relativecount = 0;
10188 asection *reldyn = 0;
10189 bfd_size_type amt;
10190 asection *attr_section = NULL;
10191 bfd_vma attr_size = 0;
10192 const char *std_attrs_section;
10194 if (! is_elf_hash_table (info->hash))
10195 return FALSE;
10197 if (info->shared)
10198 abfd->flags |= DYNAMIC;
10200 dynamic = elf_hash_table (info)->dynamic_sections_created;
10201 dynobj = elf_hash_table (info)->dynobj;
10203 emit_relocs = (info->relocatable
10204 || info->emitrelocations);
10206 finfo.info = info;
10207 finfo.output_bfd = abfd;
10208 finfo.symstrtab = _bfd_elf_stringtab_init ();
10209 if (finfo.symstrtab == NULL)
10210 return FALSE;
10212 if (! dynamic)
10214 finfo.dynsym_sec = NULL;
10215 finfo.hash_sec = NULL;
10216 finfo.symver_sec = NULL;
10218 else
10220 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
10221 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
10222 BFD_ASSERT (finfo.dynsym_sec != NULL);
10223 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
10224 /* Note that it is OK if symver_sec is NULL. */
10227 finfo.contents = NULL;
10228 finfo.external_relocs = NULL;
10229 finfo.internal_relocs = NULL;
10230 finfo.external_syms = NULL;
10231 finfo.locsym_shndx = NULL;
10232 finfo.internal_syms = NULL;
10233 finfo.indices = NULL;
10234 finfo.sections = NULL;
10235 finfo.symbuf = NULL;
10236 finfo.symshndxbuf = NULL;
10237 finfo.symbuf_count = 0;
10238 finfo.shndxbuf_size = 0;
10240 /* The object attributes have been merged. Remove the input
10241 sections from the link, and set the contents of the output
10242 secton. */
10243 std_attrs_section = get_elf_backend_data (abfd)->obj_attrs_section;
10244 for (o = abfd->sections; o != NULL; o = o->next)
10246 if ((std_attrs_section && strcmp (o->name, std_attrs_section) == 0)
10247 || strcmp (o->name, ".gnu.attributes") == 0)
10249 for (p = o->map_head.link_order; p != NULL; p = p->next)
10251 asection *input_section;
10253 if (p->type != bfd_indirect_link_order)
10254 continue;
10255 input_section = p->u.indirect.section;
10256 /* Hack: reset the SEC_HAS_CONTENTS flag so that
10257 elf_link_input_bfd ignores this section. */
10258 input_section->flags &= ~SEC_HAS_CONTENTS;
10261 attr_size = bfd_elf_obj_attr_size (abfd);
10262 if (attr_size)
10264 bfd_set_section_size (abfd, o, attr_size);
10265 attr_section = o;
10266 /* Skip this section later on. */
10267 o->map_head.link_order = NULL;
10269 else
10270 o->flags |= SEC_EXCLUDE;
10274 /* Count up the number of relocations we will output for each output
10275 section, so that we know the sizes of the reloc sections. We
10276 also figure out some maximum sizes. */
10277 max_contents_size = 0;
10278 max_external_reloc_size = 0;
10279 max_internal_reloc_count = 0;
10280 max_sym_count = 0;
10281 max_sym_shndx_count = 0;
10282 merged = FALSE;
10283 for (o = abfd->sections; o != NULL; o = o->next)
10285 struct bfd_elf_section_data *esdo = elf_section_data (o);
10286 o->reloc_count = 0;
10288 for (p = o->map_head.link_order; p != NULL; p = p->next)
10290 unsigned int reloc_count = 0;
10291 struct bfd_elf_section_data *esdi = NULL;
10292 unsigned int *rel_count1;
10294 if (p->type == bfd_section_reloc_link_order
10295 || p->type == bfd_symbol_reloc_link_order)
10296 reloc_count = 1;
10297 else if (p->type == bfd_indirect_link_order)
10299 asection *sec;
10301 sec = p->u.indirect.section;
10302 esdi = elf_section_data (sec);
10304 /* Mark all sections which are to be included in the
10305 link. This will normally be every section. We need
10306 to do this so that we can identify any sections which
10307 the linker has decided to not include. */
10308 sec->linker_mark = TRUE;
10310 if (sec->flags & SEC_MERGE)
10311 merged = TRUE;
10313 if (info->relocatable || info->emitrelocations)
10314 reloc_count = sec->reloc_count;
10315 else if (bed->elf_backend_count_relocs)
10316 reloc_count = (*bed->elf_backend_count_relocs) (info, sec);
10318 if (sec->rawsize > max_contents_size)
10319 max_contents_size = sec->rawsize;
10320 if (sec->size > max_contents_size)
10321 max_contents_size = sec->size;
10323 /* We are interested in just local symbols, not all
10324 symbols. */
10325 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
10326 && (sec->owner->flags & DYNAMIC) == 0)
10328 size_t sym_count;
10330 if (elf_bad_symtab (sec->owner))
10331 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
10332 / bed->s->sizeof_sym);
10333 else
10334 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
10336 if (sym_count > max_sym_count)
10337 max_sym_count = sym_count;
10339 if (sym_count > max_sym_shndx_count
10340 && elf_symtab_shndx (sec->owner) != 0)
10341 max_sym_shndx_count = sym_count;
10343 if ((sec->flags & SEC_RELOC) != 0)
10345 size_t ext_size;
10347 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
10348 if (ext_size > max_external_reloc_size)
10349 max_external_reloc_size = ext_size;
10350 if (sec->reloc_count > max_internal_reloc_count)
10351 max_internal_reloc_count = sec->reloc_count;
10356 if (reloc_count == 0)
10357 continue;
10359 o->reloc_count += reloc_count;
10361 /* MIPS may have a mix of REL and RELA relocs on sections.
10362 To support this curious ABI we keep reloc counts in
10363 elf_section_data too. We must be careful to add the
10364 relocations from the input section to the right output
10365 count. FIXME: Get rid of one count. We have
10366 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
10367 rel_count1 = &esdo->rel_count;
10368 if (esdi != NULL)
10370 bfd_boolean same_size;
10371 bfd_size_type entsize1;
10373 entsize1 = esdi->rel_hdr.sh_entsize;
10374 /* PR 9827: If the header size has not been set yet then
10375 assume that it will match the output section's reloc type. */
10376 if (entsize1 == 0)
10377 entsize1 = o->use_rela_p ? bed->s->sizeof_rela : bed->s->sizeof_rel;
10378 else
10379 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
10380 || entsize1 == bed->s->sizeof_rela);
10381 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
10383 if (!same_size)
10384 rel_count1 = &esdo->rel_count2;
10386 if (esdi->rel_hdr2 != NULL)
10388 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
10389 unsigned int alt_count;
10390 unsigned int *rel_count2;
10392 BFD_ASSERT (entsize2 != entsize1
10393 && (entsize2 == bed->s->sizeof_rel
10394 || entsize2 == bed->s->sizeof_rela));
10396 rel_count2 = &esdo->rel_count2;
10397 if (!same_size)
10398 rel_count2 = &esdo->rel_count;
10400 /* The following is probably too simplistic if the
10401 backend counts output relocs unusually. */
10402 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
10403 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
10404 *rel_count2 += alt_count;
10405 reloc_count -= alt_count;
10408 *rel_count1 += reloc_count;
10411 if (o->reloc_count > 0)
10412 o->flags |= SEC_RELOC;
10413 else
10415 /* Explicitly clear the SEC_RELOC flag. The linker tends to
10416 set it (this is probably a bug) and if it is set
10417 assign_section_numbers will create a reloc section. */
10418 o->flags &=~ SEC_RELOC;
10421 /* If the SEC_ALLOC flag is not set, force the section VMA to
10422 zero. This is done in elf_fake_sections as well, but forcing
10423 the VMA to 0 here will ensure that relocs against these
10424 sections are handled correctly. */
10425 if ((o->flags & SEC_ALLOC) == 0
10426 && ! o->user_set_vma)
10427 o->vma = 0;
10430 if (! info->relocatable && merged)
10431 elf_link_hash_traverse (elf_hash_table (info),
10432 _bfd_elf_link_sec_merge_syms, abfd);
10434 /* Figure out the file positions for everything but the symbol table
10435 and the relocs. We set symcount to force assign_section_numbers
10436 to create a symbol table. */
10437 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
10438 BFD_ASSERT (! abfd->output_has_begun);
10439 if (! _bfd_elf_compute_section_file_positions (abfd, info))
10440 goto error_return;
10442 /* Set sizes, and assign file positions for reloc sections. */
10443 for (o = abfd->sections; o != NULL; o = o->next)
10445 if ((o->flags & SEC_RELOC) != 0)
10447 if (!(_bfd_elf_link_size_reloc_section
10448 (abfd, &elf_section_data (o)->rel_hdr, o)))
10449 goto error_return;
10451 if (elf_section_data (o)->rel_hdr2
10452 && !(_bfd_elf_link_size_reloc_section
10453 (abfd, elf_section_data (o)->rel_hdr2, o)))
10454 goto error_return;
10457 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
10458 to count upwards while actually outputting the relocations. */
10459 elf_section_data (o)->rel_count = 0;
10460 elf_section_data (o)->rel_count2 = 0;
10463 _bfd_elf_assign_file_positions_for_relocs (abfd);
10465 /* We have now assigned file positions for all the sections except
10466 .symtab and .strtab. We start the .symtab section at the current
10467 file position, and write directly to it. We build the .strtab
10468 section in memory. */
10469 bfd_get_symcount (abfd) = 0;
10470 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
10471 /* sh_name is set in prep_headers. */
10472 symtab_hdr->sh_type = SHT_SYMTAB;
10473 /* sh_flags, sh_addr and sh_size all start off zero. */
10474 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
10475 /* sh_link is set in assign_section_numbers. */
10476 /* sh_info is set below. */
10477 /* sh_offset is set just below. */
10478 symtab_hdr->sh_addralign = (bfd_vma) 1 << bed->s->log_file_align;
10480 off = elf_tdata (abfd)->next_file_pos;
10481 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
10483 /* Note that at this point elf_tdata (abfd)->next_file_pos is
10484 incorrect. We do not yet know the size of the .symtab section.
10485 We correct next_file_pos below, after we do know the size. */
10487 /* Allocate a buffer to hold swapped out symbols. This is to avoid
10488 continuously seeking to the right position in the file. */
10489 if (! info->keep_memory || max_sym_count < 20)
10490 finfo.symbuf_size = 20;
10491 else
10492 finfo.symbuf_size = max_sym_count;
10493 amt = finfo.symbuf_size;
10494 amt *= bed->s->sizeof_sym;
10495 finfo.symbuf = (bfd_byte *) bfd_malloc (amt);
10496 if (finfo.symbuf == NULL)
10497 goto error_return;
10498 if (elf_numsections (abfd) > (SHN_LORESERVE & 0xFFFF))
10500 /* Wild guess at number of output symbols. realloc'd as needed. */
10501 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
10502 finfo.shndxbuf_size = amt;
10503 amt *= sizeof (Elf_External_Sym_Shndx);
10504 finfo.symshndxbuf = (Elf_External_Sym_Shndx *) bfd_zmalloc (amt);
10505 if (finfo.symshndxbuf == NULL)
10506 goto error_return;
10509 /* Start writing out the symbol table. The first symbol is always a
10510 dummy symbol. */
10511 if (info->strip != strip_all
10512 || emit_relocs)
10514 elfsym.st_value = 0;
10515 elfsym.st_size = 0;
10516 elfsym.st_info = 0;
10517 elfsym.st_other = 0;
10518 elfsym.st_shndx = SHN_UNDEF;
10519 if (elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
10520 NULL) != 1)
10521 goto error_return;
10524 /* Output a symbol for each section. We output these even if we are
10525 discarding local symbols, since they are used for relocs. These
10526 symbols have no names. We store the index of each one in the
10527 index field of the section, so that we can find it again when
10528 outputting relocs. */
10529 if (info->strip != strip_all
10530 || emit_relocs)
10532 elfsym.st_size = 0;
10533 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
10534 elfsym.st_other = 0;
10535 elfsym.st_value = 0;
10536 for (i = 1; i < elf_numsections (abfd); i++)
10538 o = bfd_section_from_elf_index (abfd, i);
10539 if (o != NULL)
10541 o->target_index = bfd_get_symcount (abfd);
10542 elfsym.st_shndx = i;
10543 if (!info->relocatable)
10544 elfsym.st_value = o->vma;
10545 if (elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL) != 1)
10546 goto error_return;
10551 /* Allocate some memory to hold information read in from the input
10552 files. */
10553 if (max_contents_size != 0)
10555 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
10556 if (finfo.contents == NULL)
10557 goto error_return;
10560 if (max_external_reloc_size != 0)
10562 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
10563 if (finfo.external_relocs == NULL)
10564 goto error_return;
10567 if (max_internal_reloc_count != 0)
10569 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
10570 amt *= sizeof (Elf_Internal_Rela);
10571 finfo.internal_relocs = (Elf_Internal_Rela *) bfd_malloc (amt);
10572 if (finfo.internal_relocs == NULL)
10573 goto error_return;
10576 if (max_sym_count != 0)
10578 amt = max_sym_count * bed->s->sizeof_sym;
10579 finfo.external_syms = (bfd_byte *) bfd_malloc (amt);
10580 if (finfo.external_syms == NULL)
10581 goto error_return;
10583 amt = max_sym_count * sizeof (Elf_Internal_Sym);
10584 finfo.internal_syms = (Elf_Internal_Sym *) bfd_malloc (amt);
10585 if (finfo.internal_syms == NULL)
10586 goto error_return;
10588 amt = max_sym_count * sizeof (long);
10589 finfo.indices = (long int *) bfd_malloc (amt);
10590 if (finfo.indices == NULL)
10591 goto error_return;
10593 amt = max_sym_count * sizeof (asection *);
10594 finfo.sections = (asection **) bfd_malloc (amt);
10595 if (finfo.sections == NULL)
10596 goto error_return;
10599 if (max_sym_shndx_count != 0)
10601 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
10602 finfo.locsym_shndx = (Elf_External_Sym_Shndx *) bfd_malloc (amt);
10603 if (finfo.locsym_shndx == NULL)
10604 goto error_return;
10607 if (elf_hash_table (info)->tls_sec)
10609 bfd_vma base, end = 0;
10610 asection *sec;
10612 for (sec = elf_hash_table (info)->tls_sec;
10613 sec && (sec->flags & SEC_THREAD_LOCAL);
10614 sec = sec->next)
10616 bfd_size_type size = sec->size;
10618 if (size == 0
10619 && (sec->flags & SEC_HAS_CONTENTS) == 0)
10621 struct bfd_link_order *ord = sec->map_tail.link_order;
10623 if (ord != NULL)
10624 size = ord->offset + ord->size;
10626 end = sec->vma + size;
10628 base = elf_hash_table (info)->tls_sec->vma;
10629 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
10630 elf_hash_table (info)->tls_size = end - base;
10633 /* Reorder SHF_LINK_ORDER sections. */
10634 for (o = abfd->sections; o != NULL; o = o->next)
10636 if (!elf_fixup_link_order (abfd, o))
10637 return FALSE;
10640 /* Since ELF permits relocations to be against local symbols, we
10641 must have the local symbols available when we do the relocations.
10642 Since we would rather only read the local symbols once, and we
10643 would rather not keep them in memory, we handle all the
10644 relocations for a single input file at the same time.
10646 Unfortunately, there is no way to know the total number of local
10647 symbols until we have seen all of them, and the local symbol
10648 indices precede the global symbol indices. This means that when
10649 we are generating relocatable output, and we see a reloc against
10650 a global symbol, we can not know the symbol index until we have
10651 finished examining all the local symbols to see which ones we are
10652 going to output. To deal with this, we keep the relocations in
10653 memory, and don't output them until the end of the link. This is
10654 an unfortunate waste of memory, but I don't see a good way around
10655 it. Fortunately, it only happens when performing a relocatable
10656 link, which is not the common case. FIXME: If keep_memory is set
10657 we could write the relocs out and then read them again; I don't
10658 know how bad the memory loss will be. */
10660 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
10661 sub->output_has_begun = FALSE;
10662 for (o = abfd->sections; o != NULL; o = o->next)
10664 for (p = o->map_head.link_order; p != NULL; p = p->next)
10666 if (p->type == bfd_indirect_link_order
10667 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
10668 == bfd_target_elf_flavour)
10669 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
10671 if (! sub->output_has_begun)
10673 if (! elf_link_input_bfd (&finfo, sub))
10674 goto error_return;
10675 sub->output_has_begun = TRUE;
10678 else if (p->type == bfd_section_reloc_link_order
10679 || p->type == bfd_symbol_reloc_link_order)
10681 if (! elf_reloc_link_order (abfd, info, o, p))
10682 goto error_return;
10684 else
10686 if (! _bfd_default_link_order (abfd, info, o, p))
10687 goto error_return;
10692 /* Free symbol buffer if needed. */
10693 if (!info->reduce_memory_overheads)
10695 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
10696 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
10697 && elf_tdata (sub)->symbuf)
10699 free (elf_tdata (sub)->symbuf);
10700 elf_tdata (sub)->symbuf = NULL;
10704 /* Output any global symbols that got converted to local in a
10705 version script or due to symbol visibility. We do this in a
10706 separate step since ELF requires all local symbols to appear
10707 prior to any global symbols. FIXME: We should only do this if
10708 some global symbols were, in fact, converted to become local.
10709 FIXME: Will this work correctly with the Irix 5 linker? */
10710 eoinfo.failed = FALSE;
10711 eoinfo.finfo = &finfo;
10712 eoinfo.localsyms = TRUE;
10713 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
10714 &eoinfo);
10715 if (eoinfo.failed)
10716 return FALSE;
10718 /* If backend needs to output some local symbols not present in the hash
10719 table, do it now. */
10720 if (bed->elf_backend_output_arch_local_syms)
10722 typedef int (*out_sym_func)
10723 (void *, const char *, Elf_Internal_Sym *, asection *,
10724 struct elf_link_hash_entry *);
10726 if (! ((*bed->elf_backend_output_arch_local_syms)
10727 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
10728 return FALSE;
10731 /* That wrote out all the local symbols. Finish up the symbol table
10732 with the global symbols. Even if we want to strip everything we
10733 can, we still need to deal with those global symbols that got
10734 converted to local in a version script. */
10736 /* The sh_info field records the index of the first non local symbol. */
10737 symtab_hdr->sh_info = bfd_get_symcount (abfd);
10739 if (dynamic
10740 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
10742 Elf_Internal_Sym sym;
10743 bfd_byte *dynsym = finfo.dynsym_sec->contents;
10744 long last_local = 0;
10746 /* Write out the section symbols for the output sections. */
10747 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
10749 asection *s;
10751 sym.st_size = 0;
10752 sym.st_name = 0;
10753 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
10754 sym.st_other = 0;
10756 for (s = abfd->sections; s != NULL; s = s->next)
10758 int indx;
10759 bfd_byte *dest;
10760 long dynindx;
10762 dynindx = elf_section_data (s)->dynindx;
10763 if (dynindx <= 0)
10764 continue;
10765 indx = elf_section_data (s)->this_idx;
10766 BFD_ASSERT (indx > 0);
10767 sym.st_shndx = indx;
10768 if (! check_dynsym (abfd, &sym))
10769 return FALSE;
10770 sym.st_value = s->vma;
10771 dest = dynsym + dynindx * bed->s->sizeof_sym;
10772 if (last_local < dynindx)
10773 last_local = dynindx;
10774 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
10778 /* Write out the local dynsyms. */
10779 if (elf_hash_table (info)->dynlocal)
10781 struct elf_link_local_dynamic_entry *e;
10782 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
10784 asection *s;
10785 bfd_byte *dest;
10787 /* Copy the internal symbol and turn off visibility.
10788 Note that we saved a word of storage and overwrote
10789 the original st_name with the dynstr_index. */
10790 sym = e->isym;
10791 sym.st_other &= ~ELF_ST_VISIBILITY (-1);
10793 s = bfd_section_from_elf_index (e->input_bfd,
10794 e->isym.st_shndx);
10795 if (s != NULL)
10797 sym.st_shndx =
10798 elf_section_data (s->output_section)->this_idx;
10799 if (! check_dynsym (abfd, &sym))
10800 return FALSE;
10801 sym.st_value = (s->output_section->vma
10802 + s->output_offset
10803 + e->isym.st_value);
10806 if (last_local < e->dynindx)
10807 last_local = e->dynindx;
10809 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
10810 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
10814 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
10815 last_local + 1;
10818 /* We get the global symbols from the hash table. */
10819 eoinfo.failed = FALSE;
10820 eoinfo.localsyms = FALSE;
10821 eoinfo.finfo = &finfo;
10822 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
10823 &eoinfo);
10824 if (eoinfo.failed)
10825 return FALSE;
10827 /* If backend needs to output some symbols not present in the hash
10828 table, do it now. */
10829 if (bed->elf_backend_output_arch_syms)
10831 typedef int (*out_sym_func)
10832 (void *, const char *, Elf_Internal_Sym *, asection *,
10833 struct elf_link_hash_entry *);
10835 if (! ((*bed->elf_backend_output_arch_syms)
10836 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
10837 return FALSE;
10840 /* Flush all symbols to the file. */
10841 if (! elf_link_flush_output_syms (&finfo, bed))
10842 return FALSE;
10844 /* Now we know the size of the symtab section. */
10845 off += symtab_hdr->sh_size;
10847 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
10848 if (symtab_shndx_hdr->sh_name != 0)
10850 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
10851 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
10852 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
10853 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
10854 symtab_shndx_hdr->sh_size = amt;
10856 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
10857 off, TRUE);
10859 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
10860 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
10861 return FALSE;
10865 /* Finish up and write out the symbol string table (.strtab)
10866 section. */
10867 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
10868 /* sh_name was set in prep_headers. */
10869 symstrtab_hdr->sh_type = SHT_STRTAB;
10870 symstrtab_hdr->sh_flags = 0;
10871 symstrtab_hdr->sh_addr = 0;
10872 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
10873 symstrtab_hdr->sh_entsize = 0;
10874 symstrtab_hdr->sh_link = 0;
10875 symstrtab_hdr->sh_info = 0;
10876 /* sh_offset is set just below. */
10877 symstrtab_hdr->sh_addralign = 1;
10879 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
10880 elf_tdata (abfd)->next_file_pos = off;
10882 if (bfd_get_symcount (abfd) > 0)
10884 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
10885 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
10886 return FALSE;
10889 /* Adjust the relocs to have the correct symbol indices. */
10890 for (o = abfd->sections; o != NULL; o = o->next)
10892 if ((o->flags & SEC_RELOC) == 0)
10893 continue;
10895 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
10896 elf_section_data (o)->rel_count,
10897 elf_section_data (o)->rel_hashes);
10898 if (elf_section_data (o)->rel_hdr2 != NULL)
10899 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
10900 elf_section_data (o)->rel_count2,
10901 (elf_section_data (o)->rel_hashes
10902 + elf_section_data (o)->rel_count));
10904 /* Set the reloc_count field to 0 to prevent write_relocs from
10905 trying to swap the relocs out itself. */
10906 o->reloc_count = 0;
10909 if (dynamic && info->combreloc && dynobj != NULL)
10910 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
10912 /* If we are linking against a dynamic object, or generating a
10913 shared library, finish up the dynamic linking information. */
10914 if (dynamic)
10916 bfd_byte *dyncon, *dynconend;
10918 /* Fix up .dynamic entries. */
10919 o = bfd_get_section_by_name (dynobj, ".dynamic");
10920 BFD_ASSERT (o != NULL);
10922 dyncon = o->contents;
10923 dynconend = o->contents + o->size;
10924 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
10926 Elf_Internal_Dyn dyn;
10927 const char *name;
10928 unsigned int type;
10930 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
10932 switch (dyn.d_tag)
10934 default:
10935 continue;
10936 case DT_NULL:
10937 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
10939 switch (elf_section_data (reldyn)->this_hdr.sh_type)
10941 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
10942 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
10943 default: continue;
10945 dyn.d_un.d_val = relativecount;
10946 relativecount = 0;
10947 break;
10949 continue;
10951 case DT_INIT:
10952 name = info->init_function;
10953 goto get_sym;
10954 case DT_FINI:
10955 name = info->fini_function;
10956 get_sym:
10958 struct elf_link_hash_entry *h;
10960 h = elf_link_hash_lookup (elf_hash_table (info), name,
10961 FALSE, FALSE, TRUE);
10962 if (h != NULL
10963 && (h->root.type == bfd_link_hash_defined
10964 || h->root.type == bfd_link_hash_defweak))
10966 dyn.d_un.d_ptr = h->root.u.def.value;
10967 o = h->root.u.def.section;
10968 if (o->output_section != NULL)
10969 dyn.d_un.d_ptr += (o->output_section->vma
10970 + o->output_offset);
10971 else
10973 /* The symbol is imported from another shared
10974 library and does not apply to this one. */
10975 dyn.d_un.d_ptr = 0;
10977 break;
10980 continue;
10982 case DT_PREINIT_ARRAYSZ:
10983 name = ".preinit_array";
10984 goto get_size;
10985 case DT_INIT_ARRAYSZ:
10986 name = ".init_array";
10987 goto get_size;
10988 case DT_FINI_ARRAYSZ:
10989 name = ".fini_array";
10990 get_size:
10991 o = bfd_get_section_by_name (abfd, name);
10992 if (o == NULL)
10994 (*_bfd_error_handler)
10995 (_("%B: could not find output section %s"), abfd, name);
10996 goto error_return;
10998 if (o->size == 0)
10999 (*_bfd_error_handler)
11000 (_("warning: %s section has zero size"), name);
11001 dyn.d_un.d_val = o->size;
11002 break;
11004 case DT_PREINIT_ARRAY:
11005 name = ".preinit_array";
11006 goto get_vma;
11007 case DT_INIT_ARRAY:
11008 name = ".init_array";
11009 goto get_vma;
11010 case DT_FINI_ARRAY:
11011 name = ".fini_array";
11012 goto get_vma;
11014 case DT_HASH:
11015 name = ".hash";
11016 goto get_vma;
11017 case DT_GNU_HASH:
11018 name = ".gnu.hash";
11019 goto get_vma;
11020 case DT_STRTAB:
11021 name = ".dynstr";
11022 goto get_vma;
11023 case DT_SYMTAB:
11024 name = ".dynsym";
11025 goto get_vma;
11026 case DT_VERDEF:
11027 name = ".gnu.version_d";
11028 goto get_vma;
11029 case DT_VERNEED:
11030 name = ".gnu.version_r";
11031 goto get_vma;
11032 case DT_VERSYM:
11033 name = ".gnu.version";
11034 get_vma:
11035 o = bfd_get_section_by_name (abfd, name);
11036 if (o == NULL)
11038 (*_bfd_error_handler)
11039 (_("%B: could not find output section %s"), abfd, name);
11040 goto error_return;
11042 dyn.d_un.d_ptr = o->vma;
11043 break;
11045 case DT_REL:
11046 case DT_RELA:
11047 case DT_RELSZ:
11048 case DT_RELASZ:
11049 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
11050 type = SHT_REL;
11051 else
11052 type = SHT_RELA;
11053 dyn.d_un.d_val = 0;
11054 dyn.d_un.d_ptr = 0;
11055 for (i = 1; i < elf_numsections (abfd); i++)
11057 Elf_Internal_Shdr *hdr;
11059 hdr = elf_elfsections (abfd)[i];
11060 if (hdr->sh_type == type
11061 && (hdr->sh_flags & SHF_ALLOC) != 0)
11063 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
11064 dyn.d_un.d_val += hdr->sh_size;
11065 else
11067 if (dyn.d_un.d_ptr == 0
11068 || hdr->sh_addr < dyn.d_un.d_ptr)
11069 dyn.d_un.d_ptr = hdr->sh_addr;
11073 break;
11075 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
11079 /* If we have created any dynamic sections, then output them. */
11080 if (dynobj != NULL)
11082 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
11083 goto error_return;
11085 /* Check for DT_TEXTREL (late, in case the backend removes it). */
11086 if (info->warn_shared_textrel && info->shared)
11088 bfd_byte *dyncon, *dynconend;
11090 /* Fix up .dynamic entries. */
11091 o = bfd_get_section_by_name (dynobj, ".dynamic");
11092 BFD_ASSERT (o != NULL);
11094 dyncon = o->contents;
11095 dynconend = o->contents + o->size;
11096 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
11098 Elf_Internal_Dyn dyn;
11100 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
11102 if (dyn.d_tag == DT_TEXTREL)
11104 info->callbacks->einfo
11105 (_("%P: warning: creating a DT_TEXTREL in a shared object.\n"));
11106 break;
11111 for (o = dynobj->sections; o != NULL; o = o->next)
11113 if ((o->flags & SEC_HAS_CONTENTS) == 0
11114 || o->size == 0
11115 || o->output_section == bfd_abs_section_ptr)
11116 continue;
11117 if ((o->flags & SEC_LINKER_CREATED) == 0)
11119 /* At this point, we are only interested in sections
11120 created by _bfd_elf_link_create_dynamic_sections. */
11121 continue;
11123 if (elf_hash_table (info)->stab_info.stabstr == o)
11124 continue;
11125 if (elf_hash_table (info)->eh_info.hdr_sec == o)
11126 continue;
11127 if ((elf_section_data (o->output_section)->this_hdr.sh_type
11128 != SHT_STRTAB)
11129 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
11131 /* FIXME: octets_per_byte. */
11132 if (! bfd_set_section_contents (abfd, o->output_section,
11133 o->contents,
11134 (file_ptr) o->output_offset,
11135 o->size))
11136 goto error_return;
11138 else
11140 /* The contents of the .dynstr section are actually in a
11141 stringtab. */
11142 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
11143 if (bfd_seek (abfd, off, SEEK_SET) != 0
11144 || ! _bfd_elf_strtab_emit (abfd,
11145 elf_hash_table (info)->dynstr))
11146 goto error_return;
11151 if (info->relocatable)
11153 bfd_boolean failed = FALSE;
11155 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
11156 if (failed)
11157 goto error_return;
11160 /* If we have optimized stabs strings, output them. */
11161 if (elf_hash_table (info)->stab_info.stabstr != NULL)
11163 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
11164 goto error_return;
11167 if (info->eh_frame_hdr)
11169 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
11170 goto error_return;
11173 if (finfo.symstrtab != NULL)
11174 _bfd_stringtab_free (finfo.symstrtab);
11175 if (finfo.contents != NULL)
11176 free (finfo.contents);
11177 if (finfo.external_relocs != NULL)
11178 free (finfo.external_relocs);
11179 if (finfo.internal_relocs != NULL)
11180 free (finfo.internal_relocs);
11181 if (finfo.external_syms != NULL)
11182 free (finfo.external_syms);
11183 if (finfo.locsym_shndx != NULL)
11184 free (finfo.locsym_shndx);
11185 if (finfo.internal_syms != NULL)
11186 free (finfo.internal_syms);
11187 if (finfo.indices != NULL)
11188 free (finfo.indices);
11189 if (finfo.sections != NULL)
11190 free (finfo.sections);
11191 if (finfo.symbuf != NULL)
11192 free (finfo.symbuf);
11193 if (finfo.symshndxbuf != NULL)
11194 free (finfo.symshndxbuf);
11195 for (o = abfd->sections; o != NULL; o = o->next)
11197 if ((o->flags & SEC_RELOC) != 0
11198 && elf_section_data (o)->rel_hashes != NULL)
11199 free (elf_section_data (o)->rel_hashes);
11202 elf_tdata (abfd)->linker = TRUE;
11204 if (attr_section)
11206 bfd_byte *contents = (bfd_byte *) bfd_malloc (attr_size);
11207 if (contents == NULL)
11208 return FALSE; /* Bail out and fail. */
11209 bfd_elf_set_obj_attr_contents (abfd, contents, attr_size);
11210 bfd_set_section_contents (abfd, attr_section, contents, 0, attr_size);
11211 free (contents);
11214 return TRUE;
11216 error_return:
11217 if (finfo.symstrtab != NULL)
11218 _bfd_stringtab_free (finfo.symstrtab);
11219 if (finfo.contents != NULL)
11220 free (finfo.contents);
11221 if (finfo.external_relocs != NULL)
11222 free (finfo.external_relocs);
11223 if (finfo.internal_relocs != NULL)
11224 free (finfo.internal_relocs);
11225 if (finfo.external_syms != NULL)
11226 free (finfo.external_syms);
11227 if (finfo.locsym_shndx != NULL)
11228 free (finfo.locsym_shndx);
11229 if (finfo.internal_syms != NULL)
11230 free (finfo.internal_syms);
11231 if (finfo.indices != NULL)
11232 free (finfo.indices);
11233 if (finfo.sections != NULL)
11234 free (finfo.sections);
11235 if (finfo.symbuf != NULL)
11236 free (finfo.symbuf);
11237 if (finfo.symshndxbuf != NULL)
11238 free (finfo.symshndxbuf);
11239 for (o = abfd->sections; o != NULL; o = o->next)
11241 if ((o->flags & SEC_RELOC) != 0
11242 && elf_section_data (o)->rel_hashes != NULL)
11243 free (elf_section_data (o)->rel_hashes);
11246 return FALSE;
11249 /* Initialize COOKIE for input bfd ABFD. */
11251 static bfd_boolean
11252 init_reloc_cookie (struct elf_reloc_cookie *cookie,
11253 struct bfd_link_info *info, bfd *abfd)
11255 Elf_Internal_Shdr *symtab_hdr;
11256 const struct elf_backend_data *bed;
11258 bed = get_elf_backend_data (abfd);
11259 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
11261 cookie->abfd = abfd;
11262 cookie->sym_hashes = elf_sym_hashes (abfd);
11263 cookie->bad_symtab = elf_bad_symtab (abfd);
11264 if (cookie->bad_symtab)
11266 cookie->locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
11267 cookie->extsymoff = 0;
11269 else
11271 cookie->locsymcount = symtab_hdr->sh_info;
11272 cookie->extsymoff = symtab_hdr->sh_info;
11275 if (bed->s->arch_size == 32)
11276 cookie->r_sym_shift = 8;
11277 else
11278 cookie->r_sym_shift = 32;
11280 cookie->locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
11281 if (cookie->locsyms == NULL && cookie->locsymcount != 0)
11283 cookie->locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
11284 cookie->locsymcount, 0,
11285 NULL, NULL, NULL);
11286 if (cookie->locsyms == NULL)
11288 info->callbacks->einfo (_("%P%X: can not read symbols: %E\n"));
11289 return FALSE;
11291 if (info->keep_memory)
11292 symtab_hdr->contents = (bfd_byte *) cookie->locsyms;
11294 return TRUE;
11297 /* Free the memory allocated by init_reloc_cookie, if appropriate. */
11299 static void
11300 fini_reloc_cookie (struct elf_reloc_cookie *cookie, bfd *abfd)
11302 Elf_Internal_Shdr *symtab_hdr;
11304 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
11305 if (cookie->locsyms != NULL
11306 && symtab_hdr->contents != (unsigned char *) cookie->locsyms)
11307 free (cookie->locsyms);
11310 /* Initialize the relocation information in COOKIE for input section SEC
11311 of input bfd ABFD. */
11313 static bfd_boolean
11314 init_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
11315 struct bfd_link_info *info, bfd *abfd,
11316 asection *sec)
11318 const struct elf_backend_data *bed;
11320 if (sec->reloc_count == 0)
11322 cookie->rels = NULL;
11323 cookie->relend = NULL;
11325 else
11327 bed = get_elf_backend_data (abfd);
11329 cookie->rels = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
11330 info->keep_memory);
11331 if (cookie->rels == NULL)
11332 return FALSE;
11333 cookie->rel = cookie->rels;
11334 cookie->relend = (cookie->rels
11335 + sec->reloc_count * bed->s->int_rels_per_ext_rel);
11337 cookie->rel = cookie->rels;
11338 return TRUE;
11341 /* Free the memory allocated by init_reloc_cookie_rels,
11342 if appropriate. */
11344 static void
11345 fini_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
11346 asection *sec)
11348 if (cookie->rels && elf_section_data (sec)->relocs != cookie->rels)
11349 free (cookie->rels);
11352 /* Initialize the whole of COOKIE for input section SEC. */
11354 static bfd_boolean
11355 init_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
11356 struct bfd_link_info *info,
11357 asection *sec)
11359 if (!init_reloc_cookie (cookie, info, sec->owner))
11360 goto error1;
11361 if (!init_reloc_cookie_rels (cookie, info, sec->owner, sec))
11362 goto error2;
11363 return TRUE;
11365 error2:
11366 fini_reloc_cookie (cookie, sec->owner);
11367 error1:
11368 return FALSE;
11371 /* Free the memory allocated by init_reloc_cookie_for_section,
11372 if appropriate. */
11374 static void
11375 fini_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
11376 asection *sec)
11378 fini_reloc_cookie_rels (cookie, sec);
11379 fini_reloc_cookie (cookie, sec->owner);
11382 /* Garbage collect unused sections. */
11384 /* Default gc_mark_hook. */
11386 asection *
11387 _bfd_elf_gc_mark_hook (asection *sec,
11388 struct bfd_link_info *info ATTRIBUTE_UNUSED,
11389 Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
11390 struct elf_link_hash_entry *h,
11391 Elf_Internal_Sym *sym)
11393 const char *sec_name;
11395 if (h != NULL)
11397 switch (h->root.type)
11399 case bfd_link_hash_defined:
11400 case bfd_link_hash_defweak:
11401 return h->root.u.def.section;
11403 case bfd_link_hash_common:
11404 return h->root.u.c.p->section;
11406 case bfd_link_hash_undefined:
11407 case bfd_link_hash_undefweak:
11408 /* To work around a glibc bug, keep all XXX input sections
11409 when there is an as yet undefined reference to __start_XXX
11410 or __stop_XXX symbols. The linker will later define such
11411 symbols for orphan input sections that have a name
11412 representable as a C identifier. */
11413 if (strncmp (h->root.root.string, "__start_", 8) == 0)
11414 sec_name = h->root.root.string + 8;
11415 else if (strncmp (h->root.root.string, "__stop_", 7) == 0)
11416 sec_name = h->root.root.string + 7;
11417 else
11418 sec_name = NULL;
11420 if (sec_name && *sec_name != '\0')
11422 bfd *i;
11424 for (i = info->input_bfds; i; i = i->link_next)
11426 sec = bfd_get_section_by_name (i, sec_name);
11427 if (sec)
11428 sec->flags |= SEC_KEEP;
11431 break;
11433 default:
11434 break;
11437 else
11438 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
11440 return NULL;
11443 /* COOKIE->rel describes a relocation against section SEC, which is
11444 a section we've decided to keep. Return the section that contains
11445 the relocation symbol, or NULL if no section contains it. */
11447 asection *
11448 _bfd_elf_gc_mark_rsec (struct bfd_link_info *info, asection *sec,
11449 elf_gc_mark_hook_fn gc_mark_hook,
11450 struct elf_reloc_cookie *cookie)
11452 unsigned long r_symndx;
11453 struct elf_link_hash_entry *h;
11455 r_symndx = cookie->rel->r_info >> cookie->r_sym_shift;
11456 if (r_symndx == 0)
11457 return NULL;
11459 if (r_symndx >= cookie->locsymcount
11460 || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
11462 h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
11463 while (h->root.type == bfd_link_hash_indirect
11464 || h->root.type == bfd_link_hash_warning)
11465 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11466 return (*gc_mark_hook) (sec, info, cookie->rel, h, NULL);
11469 return (*gc_mark_hook) (sec, info, cookie->rel, NULL,
11470 &cookie->locsyms[r_symndx]);
11473 /* COOKIE->rel describes a relocation against section SEC, which is
11474 a section we've decided to keep. Mark the section that contains
11475 the relocation symbol. */
11477 bfd_boolean
11478 _bfd_elf_gc_mark_reloc (struct bfd_link_info *info,
11479 asection *sec,
11480 elf_gc_mark_hook_fn gc_mark_hook,
11481 struct elf_reloc_cookie *cookie)
11483 asection *rsec;
11485 rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie);
11486 if (rsec && !rsec->gc_mark)
11488 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
11489 rsec->gc_mark = 1;
11490 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
11491 return FALSE;
11493 return TRUE;
11496 /* The mark phase of garbage collection. For a given section, mark
11497 it and any sections in this section's group, and all the sections
11498 which define symbols to which it refers. */
11500 bfd_boolean
11501 _bfd_elf_gc_mark (struct bfd_link_info *info,
11502 asection *sec,
11503 elf_gc_mark_hook_fn gc_mark_hook)
11505 bfd_boolean ret;
11506 asection *group_sec, *eh_frame;
11508 sec->gc_mark = 1;
11510 /* Mark all the sections in the group. */
11511 group_sec = elf_section_data (sec)->next_in_group;
11512 if (group_sec && !group_sec->gc_mark)
11513 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
11514 return FALSE;
11516 /* Look through the section relocs. */
11517 ret = TRUE;
11518 eh_frame = elf_eh_frame_section (sec->owner);
11519 if ((sec->flags & SEC_RELOC) != 0
11520 && sec->reloc_count > 0
11521 && sec != eh_frame)
11523 struct elf_reloc_cookie cookie;
11525 if (!init_reloc_cookie_for_section (&cookie, info, sec))
11526 ret = FALSE;
11527 else
11529 for (; cookie.rel < cookie.relend; cookie.rel++)
11530 if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, &cookie))
11532 ret = FALSE;
11533 break;
11535 fini_reloc_cookie_for_section (&cookie, sec);
11539 if (ret && eh_frame && elf_fde_list (sec))
11541 struct elf_reloc_cookie cookie;
11543 if (!init_reloc_cookie_for_section (&cookie, info, eh_frame))
11544 ret = FALSE;
11545 else
11547 if (!_bfd_elf_gc_mark_fdes (info, sec, eh_frame,
11548 gc_mark_hook, &cookie))
11549 ret = FALSE;
11550 fini_reloc_cookie_for_section (&cookie, eh_frame);
11554 return ret;
11557 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
11559 struct elf_gc_sweep_symbol_info
11561 struct bfd_link_info *info;
11562 void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
11563 bfd_boolean);
11566 static bfd_boolean
11567 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
11569 if (h->root.type == bfd_link_hash_warning)
11570 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11572 if ((h->root.type == bfd_link_hash_defined
11573 || h->root.type == bfd_link_hash_defweak)
11574 && !h->root.u.def.section->gc_mark
11575 && !(h->root.u.def.section->owner->flags & DYNAMIC))
11577 struct elf_gc_sweep_symbol_info *inf =
11578 (struct elf_gc_sweep_symbol_info *) data;
11579 (*inf->hide_symbol) (inf->info, h, TRUE);
11582 return TRUE;
11585 /* The sweep phase of garbage collection. Remove all garbage sections. */
11587 typedef bfd_boolean (*gc_sweep_hook_fn)
11588 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
11590 static bfd_boolean
11591 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
11593 bfd *sub;
11594 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11595 gc_sweep_hook_fn gc_sweep_hook = bed->gc_sweep_hook;
11596 unsigned long section_sym_count;
11597 struct elf_gc_sweep_symbol_info sweep_info;
11599 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
11601 asection *o;
11603 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
11604 continue;
11606 for (o = sub->sections; o != NULL; o = o->next)
11608 /* When any section in a section group is kept, we keep all
11609 sections in the section group. If the first member of
11610 the section group is excluded, we will also exclude the
11611 group section. */
11612 if (o->flags & SEC_GROUP)
11614 asection *first = elf_next_in_group (o);
11615 o->gc_mark = first->gc_mark;
11617 else if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
11618 || (o->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0
11619 || elf_section_data (o)->this_hdr.sh_type == SHT_NOTE)
11621 /* Keep debug, special and SHT_NOTE sections. */
11622 o->gc_mark = 1;
11625 if (o->gc_mark)
11626 continue;
11628 /* Skip sweeping sections already excluded. */
11629 if (o->flags & SEC_EXCLUDE)
11630 continue;
11632 /* Since this is early in the link process, it is simple
11633 to remove a section from the output. */
11634 o->flags |= SEC_EXCLUDE;
11636 if (info->print_gc_sections && o->size != 0)
11637 _bfd_error_handler (_("Removing unused section '%s' in file '%B'"), sub, o->name);
11639 /* But we also have to update some of the relocation
11640 info we collected before. */
11641 if (gc_sweep_hook
11642 && (o->flags & SEC_RELOC) != 0
11643 && o->reloc_count > 0
11644 && !bfd_is_abs_section (o->output_section))
11646 Elf_Internal_Rela *internal_relocs;
11647 bfd_boolean r;
11649 internal_relocs
11650 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
11651 info->keep_memory);
11652 if (internal_relocs == NULL)
11653 return FALSE;
11655 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
11657 if (elf_section_data (o)->relocs != internal_relocs)
11658 free (internal_relocs);
11660 if (!r)
11661 return FALSE;
11666 /* Remove the symbols that were in the swept sections from the dynamic
11667 symbol table. GCFIXME: Anyone know how to get them out of the
11668 static symbol table as well? */
11669 sweep_info.info = info;
11670 sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
11671 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
11672 &sweep_info);
11674 _bfd_elf_link_renumber_dynsyms (abfd, info, &section_sym_count);
11675 return TRUE;
11678 /* Propagate collected vtable information. This is called through
11679 elf_link_hash_traverse. */
11681 static bfd_boolean
11682 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
11684 if (h->root.type == bfd_link_hash_warning)
11685 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11687 /* Those that are not vtables. */
11688 if (h->vtable == NULL || h->vtable->parent == NULL)
11689 return TRUE;
11691 /* Those vtables that do not have parents, we cannot merge. */
11692 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
11693 return TRUE;
11695 /* If we've already been done, exit. */
11696 if (h->vtable->used && h->vtable->used[-1])
11697 return TRUE;
11699 /* Make sure the parent's table is up to date. */
11700 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
11702 if (h->vtable->used == NULL)
11704 /* None of this table's entries were referenced. Re-use the
11705 parent's table. */
11706 h->vtable->used = h->vtable->parent->vtable->used;
11707 h->vtable->size = h->vtable->parent->vtable->size;
11709 else
11711 size_t n;
11712 bfd_boolean *cu, *pu;
11714 /* Or the parent's entries into ours. */
11715 cu = h->vtable->used;
11716 cu[-1] = TRUE;
11717 pu = h->vtable->parent->vtable->used;
11718 if (pu != NULL)
11720 const struct elf_backend_data *bed;
11721 unsigned int log_file_align;
11723 bed = get_elf_backend_data (h->root.u.def.section->owner);
11724 log_file_align = bed->s->log_file_align;
11725 n = h->vtable->parent->vtable->size >> log_file_align;
11726 while (n--)
11728 if (*pu)
11729 *cu = TRUE;
11730 pu++;
11731 cu++;
11736 return TRUE;
11739 static bfd_boolean
11740 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
11742 asection *sec;
11743 bfd_vma hstart, hend;
11744 Elf_Internal_Rela *relstart, *relend, *rel;
11745 const struct elf_backend_data *bed;
11746 unsigned int log_file_align;
11748 if (h->root.type == bfd_link_hash_warning)
11749 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11751 /* Take care of both those symbols that do not describe vtables as
11752 well as those that are not loaded. */
11753 if (h->vtable == NULL || h->vtable->parent == NULL)
11754 return TRUE;
11756 BFD_ASSERT (h->root.type == bfd_link_hash_defined
11757 || h->root.type == bfd_link_hash_defweak);
11759 sec = h->root.u.def.section;
11760 hstart = h->root.u.def.value;
11761 hend = hstart + h->size;
11763 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
11764 if (!relstart)
11765 return *(bfd_boolean *) okp = FALSE;
11766 bed = get_elf_backend_data (sec->owner);
11767 log_file_align = bed->s->log_file_align;
11769 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
11771 for (rel = relstart; rel < relend; ++rel)
11772 if (rel->r_offset >= hstart && rel->r_offset < hend)
11774 /* If the entry is in use, do nothing. */
11775 if (h->vtable->used
11776 && (rel->r_offset - hstart) < h->vtable->size)
11778 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
11779 if (h->vtable->used[entry])
11780 continue;
11782 /* Otherwise, kill it. */
11783 rel->r_offset = rel->r_info = rel->r_addend = 0;
11786 return TRUE;
11789 /* Mark sections containing dynamically referenced symbols. When
11790 building shared libraries, we must assume that any visible symbol is
11791 referenced. */
11793 bfd_boolean
11794 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
11796 struct bfd_link_info *info = (struct bfd_link_info *) inf;
11798 if (h->root.type == bfd_link_hash_warning)
11799 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11801 if ((h->root.type == bfd_link_hash_defined
11802 || h->root.type == bfd_link_hash_defweak)
11803 && (h->ref_dynamic
11804 || (!info->executable
11805 && h->def_regular
11806 && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
11807 && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN)))
11808 h->root.u.def.section->flags |= SEC_KEEP;
11810 return TRUE;
11813 /* Keep all sections containing symbols undefined on the command-line,
11814 and the section containing the entry symbol. */
11816 void
11817 _bfd_elf_gc_keep (struct bfd_link_info *info)
11819 struct bfd_sym_chain *sym;
11821 for (sym = info->gc_sym_list; sym != NULL; sym = sym->next)
11823 struct elf_link_hash_entry *h;
11825 h = elf_link_hash_lookup (elf_hash_table (info), sym->name,
11826 FALSE, FALSE, FALSE);
11828 if (h != NULL
11829 && (h->root.type == bfd_link_hash_defined
11830 || h->root.type == bfd_link_hash_defweak)
11831 && !bfd_is_abs_section (h->root.u.def.section))
11832 h->root.u.def.section->flags |= SEC_KEEP;
11836 /* Do mark and sweep of unused sections. */
11838 bfd_boolean
11839 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
11841 bfd_boolean ok = TRUE;
11842 bfd *sub;
11843 elf_gc_mark_hook_fn gc_mark_hook;
11844 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11846 if (!bed->can_gc_sections
11847 || !is_elf_hash_table (info->hash))
11849 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
11850 return TRUE;
11853 bed->gc_keep (info);
11855 /* Try to parse each bfd's .eh_frame section. Point elf_eh_frame_section
11856 at the .eh_frame section if we can mark the FDEs individually. */
11857 _bfd_elf_begin_eh_frame_parsing (info);
11858 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
11860 asection *sec;
11861 struct elf_reloc_cookie cookie;
11863 sec = bfd_get_section_by_name (sub, ".eh_frame");
11864 if (sec && init_reloc_cookie_for_section (&cookie, info, sec))
11866 _bfd_elf_parse_eh_frame (sub, info, sec, &cookie);
11867 if (elf_section_data (sec)->sec_info)
11868 elf_eh_frame_section (sub) = sec;
11869 fini_reloc_cookie_for_section (&cookie, sec);
11872 _bfd_elf_end_eh_frame_parsing (info);
11874 /* Apply transitive closure to the vtable entry usage info. */
11875 elf_link_hash_traverse (elf_hash_table (info),
11876 elf_gc_propagate_vtable_entries_used,
11877 &ok);
11878 if (!ok)
11879 return FALSE;
11881 /* Kill the vtable relocations that were not used. */
11882 elf_link_hash_traverse (elf_hash_table (info),
11883 elf_gc_smash_unused_vtentry_relocs,
11884 &ok);
11885 if (!ok)
11886 return FALSE;
11888 /* Mark dynamically referenced symbols. */
11889 if (elf_hash_table (info)->dynamic_sections_created)
11890 elf_link_hash_traverse (elf_hash_table (info),
11891 bed->gc_mark_dynamic_ref,
11892 info);
11894 /* Grovel through relocs to find out who stays ... */
11895 gc_mark_hook = bed->gc_mark_hook;
11896 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
11898 asection *o;
11900 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
11901 continue;
11903 for (o = sub->sections; o != NULL; o = o->next)
11904 if ((o->flags & (SEC_EXCLUDE | SEC_KEEP)) == SEC_KEEP && !o->gc_mark)
11905 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
11906 return FALSE;
11909 /* Allow the backend to mark additional target specific sections. */
11910 if (bed->gc_mark_extra_sections)
11911 bed->gc_mark_extra_sections (info, gc_mark_hook);
11913 /* ... and mark SEC_EXCLUDE for those that go. */
11914 return elf_gc_sweep (abfd, info);
11917 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
11919 bfd_boolean
11920 bfd_elf_gc_record_vtinherit (bfd *abfd,
11921 asection *sec,
11922 struct elf_link_hash_entry *h,
11923 bfd_vma offset)
11925 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
11926 struct elf_link_hash_entry **search, *child;
11927 bfd_size_type extsymcount;
11928 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11930 /* The sh_info field of the symtab header tells us where the
11931 external symbols start. We don't care about the local symbols at
11932 this point. */
11933 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
11934 if (!elf_bad_symtab (abfd))
11935 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
11937 sym_hashes = elf_sym_hashes (abfd);
11938 sym_hashes_end = sym_hashes + extsymcount;
11940 /* Hunt down the child symbol, which is in this section at the same
11941 offset as the relocation. */
11942 for (search = sym_hashes; search != sym_hashes_end; ++search)
11944 if ((child = *search) != NULL
11945 && (child->root.type == bfd_link_hash_defined
11946 || child->root.type == bfd_link_hash_defweak)
11947 && child->root.u.def.section == sec
11948 && child->root.u.def.value == offset)
11949 goto win;
11952 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
11953 abfd, sec, (unsigned long) offset);
11954 bfd_set_error (bfd_error_invalid_operation);
11955 return FALSE;
11957 win:
11958 if (!child->vtable)
11960 child->vtable = (struct elf_link_virtual_table_entry *)
11961 bfd_zalloc (abfd, sizeof (*child->vtable));
11962 if (!child->vtable)
11963 return FALSE;
11965 if (!h)
11967 /* This *should* only be the absolute section. It could potentially
11968 be that someone has defined a non-global vtable though, which
11969 would be bad. It isn't worth paging in the local symbols to be
11970 sure though; that case should simply be handled by the assembler. */
11972 child->vtable->parent = (struct elf_link_hash_entry *) -1;
11974 else
11975 child->vtable->parent = h;
11977 return TRUE;
11980 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
11982 bfd_boolean
11983 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
11984 asection *sec ATTRIBUTE_UNUSED,
11985 struct elf_link_hash_entry *h,
11986 bfd_vma addend)
11988 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11989 unsigned int log_file_align = bed->s->log_file_align;
11991 if (!h->vtable)
11993 h->vtable = (struct elf_link_virtual_table_entry *)
11994 bfd_zalloc (abfd, sizeof (*h->vtable));
11995 if (!h->vtable)
11996 return FALSE;
11999 if (addend >= h->vtable->size)
12001 size_t size, bytes, file_align;
12002 bfd_boolean *ptr = h->vtable->used;
12004 /* While the symbol is undefined, we have to be prepared to handle
12005 a zero size. */
12006 file_align = 1 << log_file_align;
12007 if (h->root.type == bfd_link_hash_undefined)
12008 size = addend + file_align;
12009 else
12011 size = h->size;
12012 if (addend >= size)
12014 /* Oops! We've got a reference past the defined end of
12015 the table. This is probably a bug -- shall we warn? */
12016 size = addend + file_align;
12019 size = (size + file_align - 1) & -file_align;
12021 /* Allocate one extra entry for use as a "done" flag for the
12022 consolidation pass. */
12023 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
12025 if (ptr)
12027 ptr = (bfd_boolean *) bfd_realloc (ptr - 1, bytes);
12029 if (ptr != NULL)
12031 size_t oldbytes;
12033 oldbytes = (((h->vtable->size >> log_file_align) + 1)
12034 * sizeof (bfd_boolean));
12035 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
12038 else
12039 ptr = (bfd_boolean *) bfd_zmalloc (bytes);
12041 if (ptr == NULL)
12042 return FALSE;
12044 /* And arrange for that done flag to be at index -1. */
12045 h->vtable->used = ptr + 1;
12046 h->vtable->size = size;
12049 h->vtable->used[addend >> log_file_align] = TRUE;
12051 return TRUE;
12054 struct alloc_got_off_arg {
12055 bfd_vma gotoff;
12056 struct bfd_link_info *info;
12059 /* We need a special top-level link routine to convert got reference counts
12060 to real got offsets. */
12062 static bfd_boolean
12063 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
12065 struct alloc_got_off_arg *gofarg = (struct alloc_got_off_arg *) arg;
12066 bfd *obfd = gofarg->info->output_bfd;
12067 const struct elf_backend_data *bed = get_elf_backend_data (obfd);
12069 if (h->root.type == bfd_link_hash_warning)
12070 h = (struct elf_link_hash_entry *) h->root.u.i.link;
12072 if (h->got.refcount > 0)
12074 h->got.offset = gofarg->gotoff;
12075 gofarg->gotoff += bed->got_elt_size (obfd, gofarg->info, h, NULL, 0);
12077 else
12078 h->got.offset = (bfd_vma) -1;
12080 return TRUE;
12083 /* And an accompanying bit to work out final got entry offsets once
12084 we're done. Should be called from final_link. */
12086 bfd_boolean
12087 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
12088 struct bfd_link_info *info)
12090 bfd *i;
12091 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
12092 bfd_vma gotoff;
12093 struct alloc_got_off_arg gofarg;
12095 BFD_ASSERT (abfd == info->output_bfd);
12097 if (! is_elf_hash_table (info->hash))
12098 return FALSE;
12100 /* The GOT offset is relative to the .got section, but the GOT header is
12101 put into the .got.plt section, if the backend uses it. */
12102 if (bed->want_got_plt)
12103 gotoff = 0;
12104 else
12105 gotoff = bed->got_header_size;
12107 /* Do the local .got entries first. */
12108 for (i = info->input_bfds; i; i = i->link_next)
12110 bfd_signed_vma *local_got;
12111 bfd_size_type j, locsymcount;
12112 Elf_Internal_Shdr *symtab_hdr;
12114 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
12115 continue;
12117 local_got = elf_local_got_refcounts (i);
12118 if (!local_got)
12119 continue;
12121 symtab_hdr = &elf_tdata (i)->symtab_hdr;
12122 if (elf_bad_symtab (i))
12123 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
12124 else
12125 locsymcount = symtab_hdr->sh_info;
12127 for (j = 0; j < locsymcount; ++j)
12129 if (local_got[j] > 0)
12131 local_got[j] = gotoff;
12132 gotoff += bed->got_elt_size (abfd, info, NULL, i, j);
12134 else
12135 local_got[j] = (bfd_vma) -1;
12139 /* Then the global .got entries. .plt refcounts are handled by
12140 adjust_dynamic_symbol */
12141 gofarg.gotoff = gotoff;
12142 gofarg.info = info;
12143 elf_link_hash_traverse (elf_hash_table (info),
12144 elf_gc_allocate_got_offsets,
12145 &gofarg);
12146 return TRUE;
12149 /* Many folk need no more in the way of final link than this, once
12150 got entry reference counting is enabled. */
12152 bfd_boolean
12153 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
12155 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
12156 return FALSE;
12158 /* Invoke the regular ELF backend linker to do all the work. */
12159 return bfd_elf_final_link (abfd, info);
12162 bfd_boolean
12163 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
12165 struct elf_reloc_cookie *rcookie = (struct elf_reloc_cookie *) cookie;
12167 if (rcookie->bad_symtab)
12168 rcookie->rel = rcookie->rels;
12170 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
12172 unsigned long r_symndx;
12174 if (! rcookie->bad_symtab)
12175 if (rcookie->rel->r_offset > offset)
12176 return FALSE;
12177 if (rcookie->rel->r_offset != offset)
12178 continue;
12180 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
12181 if (r_symndx == SHN_UNDEF)
12182 return TRUE;
12184 if (r_symndx >= rcookie->locsymcount
12185 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
12187 struct elf_link_hash_entry *h;
12189 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
12191 while (h->root.type == bfd_link_hash_indirect
12192 || h->root.type == bfd_link_hash_warning)
12193 h = (struct elf_link_hash_entry *) h->root.u.i.link;
12195 if ((h->root.type == bfd_link_hash_defined
12196 || h->root.type == bfd_link_hash_defweak)
12197 && elf_discarded_section (h->root.u.def.section))
12198 return TRUE;
12199 else
12200 return FALSE;
12202 else
12204 /* It's not a relocation against a global symbol,
12205 but it could be a relocation against a local
12206 symbol for a discarded section. */
12207 asection *isec;
12208 Elf_Internal_Sym *isym;
12210 /* Need to: get the symbol; get the section. */
12211 isym = &rcookie->locsyms[r_symndx];
12212 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
12213 if (isec != NULL && elf_discarded_section (isec))
12214 return TRUE;
12216 return FALSE;
12218 return FALSE;
12221 /* Discard unneeded references to discarded sections.
12222 Returns TRUE if any section's size was changed. */
12223 /* This function assumes that the relocations are in sorted order,
12224 which is true for all known assemblers. */
12226 bfd_boolean
12227 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
12229 struct elf_reloc_cookie cookie;
12230 asection *stab, *eh;
12231 const struct elf_backend_data *bed;
12232 bfd *abfd;
12233 bfd_boolean ret = FALSE;
12235 if (info->traditional_format
12236 || !is_elf_hash_table (info->hash))
12237 return FALSE;
12239 _bfd_elf_begin_eh_frame_parsing (info);
12240 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
12242 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
12243 continue;
12245 bed = get_elf_backend_data (abfd);
12247 if ((abfd->flags & DYNAMIC) != 0)
12248 continue;
12250 eh = NULL;
12251 if (!info->relocatable)
12253 eh = bfd_get_section_by_name (abfd, ".eh_frame");
12254 if (eh != NULL
12255 && (eh->size == 0
12256 || bfd_is_abs_section (eh->output_section)))
12257 eh = NULL;
12260 stab = bfd_get_section_by_name (abfd, ".stab");
12261 if (stab != NULL
12262 && (stab->size == 0
12263 || bfd_is_abs_section (stab->output_section)
12264 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
12265 stab = NULL;
12267 if (stab == NULL
12268 && eh == NULL
12269 && bed->elf_backend_discard_info == NULL)
12270 continue;
12272 if (!init_reloc_cookie (&cookie, info, abfd))
12273 return FALSE;
12275 if (stab != NULL
12276 && stab->reloc_count > 0
12277 && init_reloc_cookie_rels (&cookie, info, abfd, stab))
12279 if (_bfd_discard_section_stabs (abfd, stab,
12280 elf_section_data (stab)->sec_info,
12281 bfd_elf_reloc_symbol_deleted_p,
12282 &cookie))
12283 ret = TRUE;
12284 fini_reloc_cookie_rels (&cookie, stab);
12287 if (eh != NULL
12288 && init_reloc_cookie_rels (&cookie, info, abfd, eh))
12290 _bfd_elf_parse_eh_frame (abfd, info, eh, &cookie);
12291 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
12292 bfd_elf_reloc_symbol_deleted_p,
12293 &cookie))
12294 ret = TRUE;
12295 fini_reloc_cookie_rels (&cookie, eh);
12298 if (bed->elf_backend_discard_info != NULL
12299 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
12300 ret = TRUE;
12302 fini_reloc_cookie (&cookie, abfd);
12304 _bfd_elf_end_eh_frame_parsing (info);
12306 if (info->eh_frame_hdr
12307 && !info->relocatable
12308 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
12309 ret = TRUE;
12311 return ret;
12314 /* For a SHT_GROUP section, return the group signature. For other
12315 sections, return the normal section name. */
12317 static const char *
12318 section_signature (asection *sec)
12320 if ((sec->flags & SEC_GROUP) != 0
12321 && elf_next_in_group (sec) != NULL
12322 && elf_group_name (elf_next_in_group (sec)) != NULL)
12323 return elf_group_name (elf_next_in_group (sec));
12324 return sec->name;
12327 void
12328 _bfd_elf_section_already_linked (bfd *abfd, asection *sec,
12329 struct bfd_link_info *info)
12331 flagword flags;
12332 const char *name, *p;
12333 struct bfd_section_already_linked *l;
12334 struct bfd_section_already_linked_hash_entry *already_linked_list;
12336 if (sec->output_section == bfd_abs_section_ptr)
12337 return;
12339 flags = sec->flags;
12341 /* Return if it isn't a linkonce section. A comdat group section
12342 also has SEC_LINK_ONCE set. */
12343 if ((flags & SEC_LINK_ONCE) == 0)
12344 return;
12346 /* Don't put group member sections on our list of already linked
12347 sections. They are handled as a group via their group section. */
12348 if (elf_sec_group (sec) != NULL)
12349 return;
12351 /* FIXME: When doing a relocatable link, we may have trouble
12352 copying relocations in other sections that refer to local symbols
12353 in the section being discarded. Those relocations will have to
12354 be converted somehow; as of this writing I'm not sure that any of
12355 the backends handle that correctly.
12357 It is tempting to instead not discard link once sections when
12358 doing a relocatable link (technically, they should be discarded
12359 whenever we are building constructors). However, that fails,
12360 because the linker winds up combining all the link once sections
12361 into a single large link once section, which defeats the purpose
12362 of having link once sections in the first place.
12364 Also, not merging link once sections in a relocatable link
12365 causes trouble for MIPS ELF, which relies on link once semantics
12366 to handle the .reginfo section correctly. */
12368 name = section_signature (sec);
12370 if (CONST_STRNEQ (name, ".gnu.linkonce.")
12371 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
12372 p++;
12373 else
12374 p = name;
12376 already_linked_list = bfd_section_already_linked_table_lookup (p);
12378 for (l = already_linked_list->entry; l != NULL; l = l->next)
12380 /* We may have 2 different types of sections on the list: group
12381 sections and linkonce sections. Match like sections. */
12382 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
12383 && strcmp (name, section_signature (l->sec)) == 0
12384 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
12386 /* The section has already been linked. See if we should
12387 issue a warning. */
12388 switch (flags & SEC_LINK_DUPLICATES)
12390 default:
12391 abort ();
12393 case SEC_LINK_DUPLICATES_DISCARD:
12394 break;
12396 case SEC_LINK_DUPLICATES_ONE_ONLY:
12397 (*_bfd_error_handler)
12398 (_("%B: ignoring duplicate section `%A'"),
12399 abfd, sec);
12400 break;
12402 case SEC_LINK_DUPLICATES_SAME_SIZE:
12403 if (sec->size != l->sec->size)
12404 (*_bfd_error_handler)
12405 (_("%B: duplicate section `%A' has different size"),
12406 abfd, sec);
12407 break;
12409 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
12410 if (sec->size != l->sec->size)
12411 (*_bfd_error_handler)
12412 (_("%B: duplicate section `%A' has different size"),
12413 abfd, sec);
12414 else if (sec->size != 0)
12416 bfd_byte *sec_contents, *l_sec_contents;
12418 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
12419 (*_bfd_error_handler)
12420 (_("%B: warning: could not read contents of section `%A'"),
12421 abfd, sec);
12422 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
12423 &l_sec_contents))
12424 (*_bfd_error_handler)
12425 (_("%B: warning: could not read contents of section `%A'"),
12426 l->sec->owner, l->sec);
12427 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
12428 (*_bfd_error_handler)
12429 (_("%B: warning: duplicate section `%A' has different contents"),
12430 abfd, sec);
12432 if (sec_contents)
12433 free (sec_contents);
12434 if (l_sec_contents)
12435 free (l_sec_contents);
12437 break;
12440 /* Set the output_section field so that lang_add_section
12441 does not create a lang_input_section structure for this
12442 section. Since there might be a symbol in the section
12443 being discarded, we must retain a pointer to the section
12444 which we are really going to use. */
12445 sec->output_section = bfd_abs_section_ptr;
12446 sec->kept_section = l->sec;
12448 if (flags & SEC_GROUP)
12450 asection *first = elf_next_in_group (sec);
12451 asection *s = first;
12453 while (s != NULL)
12455 s->output_section = bfd_abs_section_ptr;
12456 /* Record which group discards it. */
12457 s->kept_section = l->sec;
12458 s = elf_next_in_group (s);
12459 /* These lists are circular. */
12460 if (s == first)
12461 break;
12465 return;
12469 /* A single member comdat group section may be discarded by a
12470 linkonce section and vice versa. */
12472 if ((flags & SEC_GROUP) != 0)
12474 asection *first = elf_next_in_group (sec);
12476 if (first != NULL && elf_next_in_group (first) == first)
12477 /* Check this single member group against linkonce sections. */
12478 for (l = already_linked_list->entry; l != NULL; l = l->next)
12479 if ((l->sec->flags & SEC_GROUP) == 0
12480 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
12481 && bfd_elf_match_symbols_in_sections (l->sec, first, info))
12483 first->output_section = bfd_abs_section_ptr;
12484 first->kept_section = l->sec;
12485 sec->output_section = bfd_abs_section_ptr;
12486 break;
12489 else
12490 /* Check this linkonce section against single member groups. */
12491 for (l = already_linked_list->entry; l != NULL; l = l->next)
12492 if (l->sec->flags & SEC_GROUP)
12494 asection *first = elf_next_in_group (l->sec);
12496 if (first != NULL
12497 && elf_next_in_group (first) == first
12498 && bfd_elf_match_symbols_in_sections (first, sec, info))
12500 sec->output_section = bfd_abs_section_ptr;
12501 sec->kept_section = first;
12502 break;
12506 /* Do not complain on unresolved relocations in `.gnu.linkonce.r.F'
12507 referencing its discarded `.gnu.linkonce.t.F' counterpart - g++-3.4
12508 specific as g++-4.x is using COMDAT groups (without the `.gnu.linkonce'
12509 prefix) instead. `.gnu.linkonce.r.*' were the `.rodata' part of its
12510 matching `.gnu.linkonce.t.*'. If `.gnu.linkonce.r.F' is not discarded
12511 but its `.gnu.linkonce.t.F' is discarded means we chose one-only
12512 `.gnu.linkonce.t.F' section from a different bfd not requiring any
12513 `.gnu.linkonce.r.F'. Thus `.gnu.linkonce.r.F' should be discarded.
12514 The reverse order cannot happen as there is never a bfd with only the
12515 `.gnu.linkonce.r.F' section. The order of sections in a bfd does not
12516 matter as here were are looking only for cross-bfd sections. */
12518 if ((flags & SEC_GROUP) == 0 && CONST_STRNEQ (name, ".gnu.linkonce.r."))
12519 for (l = already_linked_list->entry; l != NULL; l = l->next)
12520 if ((l->sec->flags & SEC_GROUP) == 0
12521 && CONST_STRNEQ (l->sec->name, ".gnu.linkonce.t."))
12523 if (abfd != l->sec->owner)
12524 sec->output_section = bfd_abs_section_ptr;
12525 break;
12528 /* This is the first section with this name. Record it. */
12529 if (! bfd_section_already_linked_table_insert (already_linked_list, sec))
12530 info->callbacks->einfo (_("%F%P: already_linked_table: %E\n"));
12533 bfd_boolean
12534 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
12536 return sym->st_shndx == SHN_COMMON;
12539 unsigned int
12540 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
12542 return SHN_COMMON;
12545 asection *
12546 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
12548 return bfd_com_section_ptr;
12551 bfd_vma
12552 _bfd_elf_default_got_elt_size (bfd *abfd,
12553 struct bfd_link_info *info ATTRIBUTE_UNUSED,
12554 struct elf_link_hash_entry *h ATTRIBUTE_UNUSED,
12555 bfd *ibfd ATTRIBUTE_UNUSED,
12556 unsigned long symndx ATTRIBUTE_UNUSED)
12558 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
12559 return bed->s->arch_size / 8;
12562 /* Routines to support the creation of dynamic relocs. */
12564 /* Return true if NAME is a name of a relocation
12565 section associated with section S. */
12567 static bfd_boolean
12568 is_reloc_section (bfd_boolean rela, const char * name, asection * s)
12570 if (rela)
12571 return CONST_STRNEQ (name, ".rela")
12572 && strcmp (bfd_get_section_name (NULL, s), name + 5) == 0;
12574 return CONST_STRNEQ (name, ".rel")
12575 && strcmp (bfd_get_section_name (NULL, s), name + 4) == 0;
12578 /* Returns the name of the dynamic reloc section associated with SEC. */
12580 static const char *
12581 get_dynamic_reloc_section_name (bfd * abfd,
12582 asection * sec,
12583 bfd_boolean is_rela)
12585 const char * name;
12586 unsigned int strndx = elf_elfheader (abfd)->e_shstrndx;
12587 unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name;
12589 name = bfd_elf_string_from_elf_section (abfd, strndx, shnam);
12590 if (name == NULL)
12591 return NULL;
12593 if (! is_reloc_section (is_rela, name, sec))
12595 static bfd_boolean complained = FALSE;
12597 if (! complained)
12599 (*_bfd_error_handler)
12600 (_("%B: bad relocation section name `%s\'"), abfd, name);
12601 complained = TRUE;
12603 name = NULL;
12606 return name;
12609 /* Returns the dynamic reloc section associated with SEC.
12610 If necessary compute the name of the dynamic reloc section based
12611 on SEC's name (looked up in ABFD's string table) and the setting
12612 of IS_RELA. */
12614 asection *
12615 _bfd_elf_get_dynamic_reloc_section (bfd * abfd,
12616 asection * sec,
12617 bfd_boolean is_rela)
12619 asection * reloc_sec = elf_section_data (sec)->sreloc;
12621 if (reloc_sec == NULL)
12623 const char * name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
12625 if (name != NULL)
12627 reloc_sec = bfd_get_section_by_name (abfd, name);
12629 if (reloc_sec != NULL)
12630 elf_section_data (sec)->sreloc = reloc_sec;
12634 return reloc_sec;
12637 /* Returns the dynamic reloc section associated with SEC. If the
12638 section does not exist it is created and attached to the DYNOBJ
12639 bfd and stored in the SRELOC field of SEC's elf_section_data
12640 structure.
12642 ALIGNMENT is the alignment for the newly created section and
12643 IS_RELA defines whether the name should be .rela.<SEC's name>
12644 or .rel.<SEC's name>. The section name is looked up in the
12645 string table associated with ABFD. */
12647 asection *
12648 _bfd_elf_make_dynamic_reloc_section (asection * sec,
12649 bfd * dynobj,
12650 unsigned int alignment,
12651 bfd * abfd,
12652 bfd_boolean is_rela)
12654 asection * reloc_sec = elf_section_data (sec)->sreloc;
12656 if (reloc_sec == NULL)
12658 const char * name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
12660 if (name == NULL)
12661 return NULL;
12663 reloc_sec = bfd_get_section_by_name (dynobj, name);
12665 if (reloc_sec == NULL)
12667 flagword flags;
12669 flags = (SEC_HAS_CONTENTS | SEC_READONLY | SEC_IN_MEMORY | SEC_LINKER_CREATED);
12670 if ((sec->flags & SEC_ALLOC) != 0)
12671 flags |= SEC_ALLOC | SEC_LOAD;
12673 reloc_sec = bfd_make_section_with_flags (dynobj, name, flags);
12674 if (reloc_sec != NULL)
12676 if (! bfd_set_section_alignment (dynobj, reloc_sec, alignment))
12677 reloc_sec = NULL;
12681 elf_section_data (sec)->sreloc = reloc_sec;
12684 return reloc_sec;
12687 /* Copy the ELF symbol type associated with a linker hash entry. */
12688 void
12689 _bfd_elf_copy_link_hash_symbol_type (bfd *abfd ATTRIBUTE_UNUSED,
12690 struct bfd_link_hash_entry * hdest,
12691 struct bfd_link_hash_entry * hsrc)
12693 struct elf_link_hash_entry *ehdest = (struct elf_link_hash_entry *)hdest;
12694 struct elf_link_hash_entry *ehsrc = (struct elf_link_hash_entry *)hsrc;
12696 ehdest->type = ehsrc->type;