2076-01-11 H.J. Lu <hongjiu.lu@intel.com>
[binutils.git] / bfd / elflink.c
blob10b9bcd0b13bbd7596afd8e549ed076717ce7711
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
3 2005, 2006 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
29 #include "objalloc.h"
31 /* Define a symbol in a dynamic linkage section. */
33 struct elf_link_hash_entry *
34 _bfd_elf_define_linkage_sym (bfd *abfd,
35 struct bfd_link_info *info,
36 asection *sec,
37 const char *name)
39 struct elf_link_hash_entry *h;
40 struct bfd_link_hash_entry *bh;
41 const struct elf_backend_data *bed;
43 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
44 if (h != NULL)
46 /* Zap symbol defined in an as-needed lib that wasn't linked.
47 This is a symptom of a larger problem: Absolute symbols
48 defined in shared libraries can't be overridden, because we
49 lose the link to the bfd which is via the symbol section. */
50 h->root.type = bfd_link_hash_new;
53 bh = &h->root;
54 if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
55 sec, 0, NULL, FALSE,
56 get_elf_backend_data (abfd)->collect,
57 &bh))
58 return NULL;
59 h = (struct elf_link_hash_entry *) bh;
60 h->def_regular = 1;
61 h->type = STT_OBJECT;
62 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
64 bed = get_elf_backend_data (abfd);
65 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
66 return h;
69 bfd_boolean
70 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
72 flagword flags;
73 asection *s;
74 struct elf_link_hash_entry *h;
75 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
76 int ptralign;
78 /* This function may be called more than once. */
79 s = bfd_get_section_by_name (abfd, ".got");
80 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
81 return TRUE;
83 switch (bed->s->arch_size)
85 case 32:
86 ptralign = 2;
87 break;
89 case 64:
90 ptralign = 3;
91 break;
93 default:
94 bfd_set_error (bfd_error_bad_value);
95 return FALSE;
98 flags = bed->dynamic_sec_flags;
100 s = bfd_make_section_with_flags (abfd, ".got", flags);
101 if (s == NULL
102 || !bfd_set_section_alignment (abfd, s, ptralign))
103 return FALSE;
105 if (bed->want_got_plt)
107 s = bfd_make_section_with_flags (abfd, ".got.plt", flags);
108 if (s == NULL
109 || !bfd_set_section_alignment (abfd, s, ptralign))
110 return FALSE;
113 if (bed->want_got_sym)
115 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
116 (or .got.plt) section. We don't do this in the linker script
117 because we don't want to define the symbol if we are not creating
118 a global offset table. */
119 h = _bfd_elf_define_linkage_sym (abfd, info, s, "_GLOBAL_OFFSET_TABLE_");
120 elf_hash_table (info)->hgot = h;
121 if (h == NULL)
122 return FALSE;
125 /* The first bit of the global offset table is the header. */
126 s->size += bed->got_header_size;
128 return TRUE;
131 /* Create a strtab to hold the dynamic symbol names. */
132 static bfd_boolean
133 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
135 struct elf_link_hash_table *hash_table;
137 hash_table = elf_hash_table (info);
138 if (hash_table->dynobj == NULL)
139 hash_table->dynobj = abfd;
141 if (hash_table->dynstr == NULL)
143 hash_table->dynstr = _bfd_elf_strtab_init ();
144 if (hash_table->dynstr == NULL)
145 return FALSE;
147 return TRUE;
150 /* Create some sections which will be filled in with dynamic linking
151 information. ABFD is an input file which requires dynamic sections
152 to be created. The dynamic sections take up virtual memory space
153 when the final executable is run, so we need to create them before
154 addresses are assigned to the output sections. We work out the
155 actual contents and size of these sections later. */
157 bfd_boolean
158 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
160 flagword flags;
161 register asection *s;
162 const struct elf_backend_data *bed;
164 if (! is_elf_hash_table (info->hash))
165 return FALSE;
167 if (elf_hash_table (info)->dynamic_sections_created)
168 return TRUE;
170 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
171 return FALSE;
173 abfd = elf_hash_table (info)->dynobj;
174 bed = get_elf_backend_data (abfd);
176 flags = bed->dynamic_sec_flags;
178 /* A dynamically linked executable has a .interp section, but a
179 shared library does not. */
180 if (info->executable)
182 s = bfd_make_section_with_flags (abfd, ".interp",
183 flags | SEC_READONLY);
184 if (s == NULL)
185 return FALSE;
188 /* Create sections to hold version informations. These are removed
189 if they are not needed. */
190 s = bfd_make_section_with_flags (abfd, ".gnu.version_d",
191 flags | SEC_READONLY);
192 if (s == NULL
193 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
194 return FALSE;
196 s = bfd_make_section_with_flags (abfd, ".gnu.version",
197 flags | SEC_READONLY);
198 if (s == NULL
199 || ! bfd_set_section_alignment (abfd, s, 1))
200 return FALSE;
202 s = bfd_make_section_with_flags (abfd, ".gnu.version_r",
203 flags | SEC_READONLY);
204 if (s == NULL
205 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
206 return FALSE;
208 s = bfd_make_section_with_flags (abfd, ".dynsym",
209 flags | SEC_READONLY);
210 if (s == NULL
211 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
212 return FALSE;
214 s = bfd_make_section_with_flags (abfd, ".dynstr",
215 flags | SEC_READONLY);
216 if (s == NULL)
217 return FALSE;
219 s = bfd_make_section_with_flags (abfd, ".dynamic", flags);
220 if (s == NULL
221 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
222 return FALSE;
224 /* The special symbol _DYNAMIC is always set to the start of the
225 .dynamic section. We could set _DYNAMIC in a linker script, but we
226 only want to define it if we are, in fact, creating a .dynamic
227 section. We don't want to define it if there is no .dynamic
228 section, since on some ELF platforms the start up code examines it
229 to decide how to initialize the process. */
230 if (!_bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC"))
231 return FALSE;
233 if (info->emit_hash)
235 s = bfd_make_section_with_flags (abfd, ".hash", flags | SEC_READONLY);
236 if (s == NULL
237 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
238 return FALSE;
239 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
242 if (info->emit_gnu_hash)
244 s = bfd_make_section_with_flags (abfd, ".gnu.hash",
245 flags | SEC_READONLY);
246 if (s == NULL
247 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
248 return FALSE;
249 /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
250 4 32-bit words followed by variable count of 64-bit words, then
251 variable count of 32-bit words. */
252 if (bed->s->arch_size == 64)
253 elf_section_data (s)->this_hdr.sh_entsize = 0;
254 else
255 elf_section_data (s)->this_hdr.sh_entsize = 4;
258 /* Let the backend create the rest of the sections. This lets the
259 backend set the right flags. The backend will normally create
260 the .got and .plt sections. */
261 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
262 return FALSE;
264 elf_hash_table (info)->dynamic_sections_created = TRUE;
266 return TRUE;
269 /* Create dynamic sections when linking against a dynamic object. */
271 bfd_boolean
272 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
274 flagword flags, pltflags;
275 struct elf_link_hash_entry *h;
276 asection *s;
277 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
279 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
280 .rel[a].bss sections. */
281 flags = bed->dynamic_sec_flags;
283 pltflags = flags;
284 if (bed->plt_not_loaded)
285 /* We do not clear SEC_ALLOC here because we still want the OS to
286 allocate space for the section; it's just that there's nothing
287 to read in from the object file. */
288 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
289 else
290 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
291 if (bed->plt_readonly)
292 pltflags |= SEC_READONLY;
294 s = bfd_make_section_with_flags (abfd, ".plt", pltflags);
295 if (s == NULL
296 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
297 return FALSE;
299 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
300 .plt section. */
301 if (bed->want_plt_sym)
303 h = _bfd_elf_define_linkage_sym (abfd, info, s,
304 "_PROCEDURE_LINKAGE_TABLE_");
305 elf_hash_table (info)->hplt = h;
306 if (h == NULL)
307 return FALSE;
310 s = bfd_make_section_with_flags (abfd,
311 (bed->default_use_rela_p
312 ? ".rela.plt" : ".rel.plt"),
313 flags | SEC_READONLY);
314 if (s == NULL
315 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
316 return FALSE;
318 if (! _bfd_elf_create_got_section (abfd, info))
319 return FALSE;
321 if (bed->want_dynbss)
323 /* The .dynbss section is a place to put symbols which are defined
324 by dynamic objects, are referenced by regular objects, and are
325 not functions. We must allocate space for them in the process
326 image and use a R_*_COPY reloc to tell the dynamic linker to
327 initialize them at run time. The linker script puts the .dynbss
328 section into the .bss section of the final image. */
329 s = bfd_make_section_with_flags (abfd, ".dynbss",
330 (SEC_ALLOC
331 | SEC_LINKER_CREATED));
332 if (s == NULL)
333 return FALSE;
335 /* The .rel[a].bss section holds copy relocs. This section is not
336 normally needed. We need to create it here, though, so that the
337 linker will map it to an output section. We can't just create it
338 only if we need it, because we will not know whether we need it
339 until we have seen all the input files, and the first time the
340 main linker code calls BFD after examining all the input files
341 (size_dynamic_sections) the input sections have already been
342 mapped to the output sections. If the section turns out not to
343 be needed, we can discard it later. We will never need this
344 section when generating a shared object, since they do not use
345 copy relocs. */
346 if (! info->shared)
348 s = bfd_make_section_with_flags (abfd,
349 (bed->default_use_rela_p
350 ? ".rela.bss" : ".rel.bss"),
351 flags | SEC_READONLY);
352 if (s == NULL
353 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
354 return FALSE;
358 return TRUE;
361 /* Record a new dynamic symbol. We record the dynamic symbols as we
362 read the input files, since we need to have a list of all of them
363 before we can determine the final sizes of the output sections.
364 Note that we may actually call this function even though we are not
365 going to output any dynamic symbols; in some cases we know that a
366 symbol should be in the dynamic symbol table, but only if there is
367 one. */
369 bfd_boolean
370 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
371 struct elf_link_hash_entry *h)
373 if (h->dynindx == -1)
375 struct elf_strtab_hash *dynstr;
376 char *p;
377 const char *name;
378 bfd_size_type indx;
380 /* XXX: The ABI draft says the linker must turn hidden and
381 internal symbols into STB_LOCAL symbols when producing the
382 DSO. However, if ld.so honors st_other in the dynamic table,
383 this would not be necessary. */
384 switch (ELF_ST_VISIBILITY (h->other))
386 case STV_INTERNAL:
387 case STV_HIDDEN:
388 if (h->root.type != bfd_link_hash_undefined
389 && h->root.type != bfd_link_hash_undefweak)
391 h->forced_local = 1;
392 if (!elf_hash_table (info)->is_relocatable_executable)
393 return TRUE;
396 default:
397 break;
400 h->dynindx = elf_hash_table (info)->dynsymcount;
401 ++elf_hash_table (info)->dynsymcount;
403 dynstr = elf_hash_table (info)->dynstr;
404 if (dynstr == NULL)
406 /* Create a strtab to hold the dynamic symbol names. */
407 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
408 if (dynstr == NULL)
409 return FALSE;
412 /* We don't put any version information in the dynamic string
413 table. */
414 name = h->root.root.string;
415 p = strchr (name, ELF_VER_CHR);
416 if (p != NULL)
417 /* We know that the p points into writable memory. In fact,
418 there are only a few symbols that have read-only names, being
419 those like _GLOBAL_OFFSET_TABLE_ that are created specially
420 by the backends. Most symbols will have names pointing into
421 an ELF string table read from a file, or to objalloc memory. */
422 *p = 0;
424 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
426 if (p != NULL)
427 *p = ELF_VER_CHR;
429 if (indx == (bfd_size_type) -1)
430 return FALSE;
431 h->dynstr_index = indx;
434 return TRUE;
437 /* Mark a symbol dynamic. */
439 void
440 bfd_elf_link_mark_dynamic_symbol (struct bfd_link_info *info,
441 struct elf_link_hash_entry *h)
443 struct bfd_elf_dynamic_list *d = info->dynamic;
445 if (d == NULL || info->relocatable)
446 return;
448 if ((*d->match) (&d->head, NULL, h->root.root.string))
449 h->dynamic = 1;
452 /* Record an assignment to a symbol made by a linker script. We need
453 this in case some dynamic object refers to this symbol. */
455 bfd_boolean
456 bfd_elf_record_link_assignment (bfd *output_bfd,
457 struct bfd_link_info *info,
458 const char *name,
459 bfd_boolean provide,
460 bfd_boolean hidden)
462 struct elf_link_hash_entry *h;
463 struct elf_link_hash_table *htab;
465 if (!is_elf_hash_table (info->hash))
466 return TRUE;
468 htab = elf_hash_table (info);
469 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
470 if (h == NULL)
471 return provide;
473 /* Since we're defining the symbol, don't let it seem to have not
474 been defined. record_dynamic_symbol and size_dynamic_sections
475 may depend on this. */
476 if (h->root.type == bfd_link_hash_undefweak
477 || h->root.type == bfd_link_hash_undefined)
479 h->root.type = bfd_link_hash_new;
480 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
481 bfd_link_repair_undef_list (&htab->root);
484 if (h->root.type == bfd_link_hash_new)
486 bfd_elf_link_mark_dynamic_symbol (info, h);
487 h->non_elf = 0;
490 /* If this symbol is being provided by the linker script, and it is
491 currently defined by a dynamic object, but not by a regular
492 object, then mark it as undefined so that the generic linker will
493 force the correct value. */
494 if (provide
495 && h->def_dynamic
496 && !h->def_regular)
497 h->root.type = bfd_link_hash_undefined;
499 /* If this symbol is not being provided by the linker script, and it is
500 currently defined by a dynamic object, but not by a regular object,
501 then clear out any version information because the symbol will not be
502 associated with the dynamic object any more. */
503 if (!provide
504 && h->def_dynamic
505 && !h->def_regular)
506 h->verinfo.verdef = NULL;
508 h->def_regular = 1;
510 if (provide && hidden)
512 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
514 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
515 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
518 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
519 and executables. */
520 if (!info->relocatable
521 && h->dynindx != -1
522 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
523 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
524 h->forced_local = 1;
526 if ((h->def_dynamic
527 || h->ref_dynamic
528 || info->shared
529 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
530 && h->dynindx == -1)
532 if (! bfd_elf_link_record_dynamic_symbol (info, h))
533 return FALSE;
535 /* If this is a weak defined symbol, and we know a corresponding
536 real symbol from the same dynamic object, make sure the real
537 symbol is also made into a dynamic symbol. */
538 if (h->u.weakdef != NULL
539 && h->u.weakdef->dynindx == -1)
541 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
542 return FALSE;
546 return TRUE;
549 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
550 success, and 2 on a failure caused by attempting to record a symbol
551 in a discarded section, eg. a discarded link-once section symbol. */
554 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
555 bfd *input_bfd,
556 long input_indx)
558 bfd_size_type amt;
559 struct elf_link_local_dynamic_entry *entry;
560 struct elf_link_hash_table *eht;
561 struct elf_strtab_hash *dynstr;
562 unsigned long dynstr_index;
563 char *name;
564 Elf_External_Sym_Shndx eshndx;
565 char esym[sizeof (Elf64_External_Sym)];
567 if (! is_elf_hash_table (info->hash))
568 return 0;
570 /* See if the entry exists already. */
571 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
572 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
573 return 1;
575 amt = sizeof (*entry);
576 entry = bfd_alloc (input_bfd, amt);
577 if (entry == NULL)
578 return 0;
580 /* Go find the symbol, so that we can find it's name. */
581 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
582 1, input_indx, &entry->isym, esym, &eshndx))
584 bfd_release (input_bfd, entry);
585 return 0;
588 if (entry->isym.st_shndx != SHN_UNDEF
589 && (entry->isym.st_shndx < SHN_LORESERVE
590 || entry->isym.st_shndx > SHN_HIRESERVE))
592 asection *s;
594 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
595 if (s == NULL || bfd_is_abs_section (s->output_section))
597 /* We can still bfd_release here as nothing has done another
598 bfd_alloc. We can't do this later in this function. */
599 bfd_release (input_bfd, entry);
600 return 2;
604 name = (bfd_elf_string_from_elf_section
605 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
606 entry->isym.st_name));
608 dynstr = elf_hash_table (info)->dynstr;
609 if (dynstr == NULL)
611 /* Create a strtab to hold the dynamic symbol names. */
612 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
613 if (dynstr == NULL)
614 return 0;
617 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
618 if (dynstr_index == (unsigned long) -1)
619 return 0;
620 entry->isym.st_name = dynstr_index;
622 eht = elf_hash_table (info);
624 entry->next = eht->dynlocal;
625 eht->dynlocal = entry;
626 entry->input_bfd = input_bfd;
627 entry->input_indx = input_indx;
628 eht->dynsymcount++;
630 /* Whatever binding the symbol had before, it's now local. */
631 entry->isym.st_info
632 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
634 /* The dynindx will be set at the end of size_dynamic_sections. */
636 return 1;
639 /* Return the dynindex of a local dynamic symbol. */
641 long
642 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
643 bfd *input_bfd,
644 long input_indx)
646 struct elf_link_local_dynamic_entry *e;
648 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
649 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
650 return e->dynindx;
651 return -1;
654 /* This function is used to renumber the dynamic symbols, if some of
655 them are removed because they are marked as local. This is called
656 via elf_link_hash_traverse. */
658 static bfd_boolean
659 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
660 void *data)
662 size_t *count = data;
664 if (h->root.type == bfd_link_hash_warning)
665 h = (struct elf_link_hash_entry *) h->root.u.i.link;
667 if (h->forced_local)
668 return TRUE;
670 if (h->dynindx != -1)
671 h->dynindx = ++(*count);
673 return TRUE;
677 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
678 STB_LOCAL binding. */
680 static bfd_boolean
681 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
682 void *data)
684 size_t *count = data;
686 if (h->root.type == bfd_link_hash_warning)
687 h = (struct elf_link_hash_entry *) h->root.u.i.link;
689 if (!h->forced_local)
690 return TRUE;
692 if (h->dynindx != -1)
693 h->dynindx = ++(*count);
695 return TRUE;
698 /* Return true if the dynamic symbol for a given section should be
699 omitted when creating a shared library. */
700 bfd_boolean
701 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
702 struct bfd_link_info *info,
703 asection *p)
705 struct elf_link_hash_table *htab;
707 switch (elf_section_data (p)->this_hdr.sh_type)
709 case SHT_PROGBITS:
710 case SHT_NOBITS:
711 /* If sh_type is yet undecided, assume it could be
712 SHT_PROGBITS/SHT_NOBITS. */
713 case SHT_NULL:
714 htab = elf_hash_table (info);
715 if (p == htab->tls_sec)
716 return FALSE;
718 if (htab->text_index_section != NULL)
719 return p != htab->text_index_section && p != htab->data_index_section;
721 if (strcmp (p->name, ".got") == 0
722 || strcmp (p->name, ".got.plt") == 0
723 || strcmp (p->name, ".plt") == 0)
725 asection *ip;
727 if (htab->dynobj != NULL
728 && (ip = bfd_get_section_by_name (htab->dynobj, p->name)) != NULL
729 && (ip->flags & SEC_LINKER_CREATED)
730 && ip->output_section == p)
731 return TRUE;
733 return FALSE;
735 /* There shouldn't be section relative relocations
736 against any other section. */
737 default:
738 return TRUE;
742 /* Assign dynsym indices. In a shared library we generate a section
743 symbol for each output section, which come first. Next come symbols
744 which have been forced to local binding. Then all of the back-end
745 allocated local dynamic syms, followed by the rest of the global
746 symbols. */
748 static unsigned long
749 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
750 struct bfd_link_info *info,
751 unsigned long *section_sym_count)
753 unsigned long dynsymcount = 0;
755 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
757 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
758 asection *p;
759 for (p = output_bfd->sections; p ; p = p->next)
760 if ((p->flags & SEC_EXCLUDE) == 0
761 && (p->flags & SEC_ALLOC) != 0
762 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
763 elf_section_data (p)->dynindx = ++dynsymcount;
764 else
765 elf_section_data (p)->dynindx = 0;
767 *section_sym_count = dynsymcount;
769 elf_link_hash_traverse (elf_hash_table (info),
770 elf_link_renumber_local_hash_table_dynsyms,
771 &dynsymcount);
773 if (elf_hash_table (info)->dynlocal)
775 struct elf_link_local_dynamic_entry *p;
776 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
777 p->dynindx = ++dynsymcount;
780 elf_link_hash_traverse (elf_hash_table (info),
781 elf_link_renumber_hash_table_dynsyms,
782 &dynsymcount);
784 /* There is an unused NULL entry at the head of the table which
785 we must account for in our count. Unless there weren't any
786 symbols, which means we'll have no table at all. */
787 if (dynsymcount != 0)
788 ++dynsymcount;
790 elf_hash_table (info)->dynsymcount = dynsymcount;
791 return dynsymcount;
794 /* This function is called when we want to define a new symbol. It
795 handles the various cases which arise when we find a definition in
796 a dynamic object, or when there is already a definition in a
797 dynamic object. The new symbol is described by NAME, SYM, PSEC,
798 and PVALUE. We set SYM_HASH to the hash table entry. We set
799 OVERRIDE if the old symbol is overriding a new definition. We set
800 TYPE_CHANGE_OK if it is OK for the type to change. We set
801 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
802 change, we mean that we shouldn't warn if the type or size does
803 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
804 object is overridden by a regular object. */
806 bfd_boolean
807 _bfd_elf_merge_symbol (bfd *abfd,
808 struct bfd_link_info *info,
809 const char *name,
810 Elf_Internal_Sym *sym,
811 asection **psec,
812 bfd_vma *pvalue,
813 unsigned int *pold_alignment,
814 struct elf_link_hash_entry **sym_hash,
815 bfd_boolean *skip,
816 bfd_boolean *override,
817 bfd_boolean *type_change_ok,
818 bfd_boolean *size_change_ok)
820 asection *sec, *oldsec;
821 struct elf_link_hash_entry *h;
822 struct elf_link_hash_entry *flip;
823 int bind;
824 bfd *oldbfd;
825 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
826 bfd_boolean newweak, oldweak;
827 const struct elf_backend_data *bed;
829 *skip = FALSE;
830 *override = FALSE;
832 sec = *psec;
833 bind = ELF_ST_BIND (sym->st_info);
835 /* Silently discard TLS symbols from --just-syms. There's no way to
836 combine a static TLS block with a new TLS block for this executable. */
837 if (ELF_ST_TYPE (sym->st_info) == STT_TLS
838 && sec->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
840 *skip = TRUE;
841 return TRUE;
844 if (! bfd_is_und_section (sec))
845 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
846 else
847 h = ((struct elf_link_hash_entry *)
848 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
849 if (h == NULL)
850 return FALSE;
851 *sym_hash = h;
853 /* This code is for coping with dynamic objects, and is only useful
854 if we are doing an ELF link. */
855 if (info->hash->creator != abfd->xvec)
856 return TRUE;
858 /* For merging, we only care about real symbols. */
860 while (h->root.type == bfd_link_hash_indirect
861 || h->root.type == bfd_link_hash_warning)
862 h = (struct elf_link_hash_entry *) h->root.u.i.link;
864 /* If we just created the symbol, mark it as being an ELF symbol.
865 Other than that, there is nothing to do--there is no merge issue
866 with a newly defined symbol--so we just return. */
868 if (h->root.type == bfd_link_hash_new)
870 bfd_elf_link_mark_dynamic_symbol (info, h);
871 h->non_elf = 0;
872 return TRUE;
875 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
876 existing symbol. */
878 switch (h->root.type)
880 default:
881 oldbfd = NULL;
882 oldsec = NULL;
883 break;
885 case bfd_link_hash_undefined:
886 case bfd_link_hash_undefweak:
887 oldbfd = h->root.u.undef.abfd;
888 oldsec = NULL;
889 break;
891 case bfd_link_hash_defined:
892 case bfd_link_hash_defweak:
893 oldbfd = h->root.u.def.section->owner;
894 oldsec = h->root.u.def.section;
895 break;
897 case bfd_link_hash_common:
898 oldbfd = h->root.u.c.p->section->owner;
899 oldsec = h->root.u.c.p->section;
900 break;
903 /* In cases involving weak versioned symbols, we may wind up trying
904 to merge a symbol with itself. Catch that here, to avoid the
905 confusion that results if we try to override a symbol with
906 itself. The additional tests catch cases like
907 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
908 dynamic object, which we do want to handle here. */
909 if (abfd == oldbfd
910 && ((abfd->flags & DYNAMIC) == 0
911 || !h->def_regular))
912 return TRUE;
914 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
915 respectively, is from a dynamic object. */
917 newdyn = (abfd->flags & DYNAMIC) != 0;
919 olddyn = FALSE;
920 if (oldbfd != NULL)
921 olddyn = (oldbfd->flags & DYNAMIC) != 0;
922 else if (oldsec != NULL)
924 /* This handles the special SHN_MIPS_{TEXT,DATA} section
925 indices used by MIPS ELF. */
926 olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
929 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
930 respectively, appear to be a definition rather than reference. */
932 newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
934 olddef = (h->root.type != bfd_link_hash_undefined
935 && h->root.type != bfd_link_hash_undefweak
936 && h->root.type != bfd_link_hash_common);
938 /* When we try to create a default indirect symbol from the dynamic
939 definition with the default version, we skip it if its type and
940 the type of existing regular definition mismatch. We only do it
941 if the existing regular definition won't be dynamic. */
942 if (pold_alignment == NULL
943 && !info->shared
944 && !info->export_dynamic
945 && !h->ref_dynamic
946 && newdyn
947 && newdef
948 && !olddyn
949 && (olddef || h->root.type == bfd_link_hash_common)
950 && ELF_ST_TYPE (sym->st_info) != h->type
951 && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
952 && h->type != STT_NOTYPE)
954 *skip = TRUE;
955 return TRUE;
958 /* Check TLS symbol. We don't check undefined symbol introduced by
959 "ld -u". */
960 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
961 && ELF_ST_TYPE (sym->st_info) != h->type
962 && oldbfd != NULL)
964 bfd *ntbfd, *tbfd;
965 bfd_boolean ntdef, tdef;
966 asection *ntsec, *tsec;
968 if (h->type == STT_TLS)
970 ntbfd = abfd;
971 ntsec = sec;
972 ntdef = newdef;
973 tbfd = oldbfd;
974 tsec = oldsec;
975 tdef = olddef;
977 else
979 ntbfd = oldbfd;
980 ntsec = oldsec;
981 ntdef = olddef;
982 tbfd = abfd;
983 tsec = sec;
984 tdef = newdef;
987 if (tdef && ntdef)
988 (*_bfd_error_handler)
989 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
990 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
991 else if (!tdef && !ntdef)
992 (*_bfd_error_handler)
993 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
994 tbfd, ntbfd, h->root.root.string);
995 else if (tdef)
996 (*_bfd_error_handler)
997 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
998 tbfd, tsec, ntbfd, h->root.root.string);
999 else
1000 (*_bfd_error_handler)
1001 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
1002 tbfd, ntbfd, ntsec, h->root.root.string);
1004 bfd_set_error (bfd_error_bad_value);
1005 return FALSE;
1008 /* We need to remember if a symbol has a definition in a dynamic
1009 object or is weak in all dynamic objects. Internal and hidden
1010 visibility will make it unavailable to dynamic objects. */
1011 if (newdyn && !h->dynamic_def)
1013 if (!bfd_is_und_section (sec))
1014 h->dynamic_def = 1;
1015 else
1017 /* Check if this symbol is weak in all dynamic objects. If it
1018 is the first time we see it in a dynamic object, we mark
1019 if it is weak. Otherwise, we clear it. */
1020 if (!h->ref_dynamic)
1022 if (bind == STB_WEAK)
1023 h->dynamic_weak = 1;
1025 else if (bind != STB_WEAK)
1026 h->dynamic_weak = 0;
1030 /* If the old symbol has non-default visibility, we ignore the new
1031 definition from a dynamic object. */
1032 if (newdyn
1033 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1034 && !bfd_is_und_section (sec))
1036 *skip = TRUE;
1037 /* Make sure this symbol is dynamic. */
1038 h->ref_dynamic = 1;
1039 /* A protected symbol has external availability. Make sure it is
1040 recorded as dynamic.
1042 FIXME: Should we check type and size for protected symbol? */
1043 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1044 return bfd_elf_link_record_dynamic_symbol (info, h);
1045 else
1046 return TRUE;
1048 else if (!newdyn
1049 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1050 && h->def_dynamic)
1052 /* If the new symbol with non-default visibility comes from a
1053 relocatable file and the old definition comes from a dynamic
1054 object, we remove the old definition. */
1055 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1057 /* Handle the case where the old dynamic definition is
1058 default versioned. We need to copy the symbol info from
1059 the symbol with default version to the normal one if it
1060 was referenced before. */
1061 if (h->ref_regular)
1063 const struct elf_backend_data *bed
1064 = get_elf_backend_data (abfd);
1065 struct elf_link_hash_entry *vh = *sym_hash;
1066 vh->root.type = h->root.type;
1067 h->root.type = bfd_link_hash_indirect;
1068 (*bed->elf_backend_copy_indirect_symbol) (info, vh, h);
1069 /* Protected symbols will override the dynamic definition
1070 with default version. */
1071 if (ELF_ST_VISIBILITY (sym->st_other) == STV_PROTECTED)
1073 h->root.u.i.link = (struct bfd_link_hash_entry *) vh;
1074 vh->dynamic_def = 1;
1075 vh->ref_dynamic = 1;
1077 else
1079 h->root.type = vh->root.type;
1080 vh->ref_dynamic = 0;
1081 /* We have to hide it here since it was made dynamic
1082 global with extra bits when the symbol info was
1083 copied from the old dynamic definition. */
1084 (*bed->elf_backend_hide_symbol) (info, vh, TRUE);
1086 h = vh;
1088 else
1089 h = *sym_hash;
1092 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1093 && bfd_is_und_section (sec))
1095 /* If the new symbol is undefined and the old symbol was
1096 also undefined before, we need to make sure
1097 _bfd_generic_link_add_one_symbol doesn't mess
1098 up the linker hash table undefs list. Since the old
1099 definition came from a dynamic object, it is still on the
1100 undefs list. */
1101 h->root.type = bfd_link_hash_undefined;
1102 h->root.u.undef.abfd = abfd;
1104 else
1106 h->root.type = bfd_link_hash_new;
1107 h->root.u.undef.abfd = NULL;
1110 if (h->def_dynamic)
1112 h->def_dynamic = 0;
1113 h->ref_dynamic = 1;
1114 h->dynamic_def = 1;
1116 /* FIXME: Should we check type and size for protected symbol? */
1117 h->size = 0;
1118 h->type = 0;
1119 return TRUE;
1122 /* Differentiate strong and weak symbols. */
1123 newweak = bind == STB_WEAK;
1124 oldweak = (h->root.type == bfd_link_hash_defweak
1125 || h->root.type == bfd_link_hash_undefweak);
1127 /* If a new weak symbol definition comes from a regular file and the
1128 old symbol comes from a dynamic library, we treat the new one as
1129 strong. Similarly, an old weak symbol definition from a regular
1130 file is treated as strong when the new symbol comes from a dynamic
1131 library. Further, an old weak symbol from a dynamic library is
1132 treated as strong if the new symbol is from a dynamic library.
1133 This reflects the way glibc's ld.so works.
1135 Do this before setting *type_change_ok or *size_change_ok so that
1136 we warn properly when dynamic library symbols are overridden. */
1138 if (newdef && !newdyn && olddyn)
1139 newweak = FALSE;
1140 if (olddef && newdyn)
1141 oldweak = FALSE;
1143 /* It's OK to change the type if either the existing symbol or the
1144 new symbol is weak. A type change is also OK if the old symbol
1145 is undefined and the new symbol is defined. */
1147 if (oldweak
1148 || newweak
1149 || (newdef
1150 && h->root.type == bfd_link_hash_undefined))
1151 *type_change_ok = TRUE;
1153 /* It's OK to change the size if either the existing symbol or the
1154 new symbol is weak, or if the old symbol is undefined. */
1156 if (*type_change_ok
1157 || h->root.type == bfd_link_hash_undefined)
1158 *size_change_ok = TRUE;
1160 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1161 symbol, respectively, appears to be a common symbol in a dynamic
1162 object. If a symbol appears in an uninitialized section, and is
1163 not weak, and is not a function, then it may be a common symbol
1164 which was resolved when the dynamic object was created. We want
1165 to treat such symbols specially, because they raise special
1166 considerations when setting the symbol size: if the symbol
1167 appears as a common symbol in a regular object, and the size in
1168 the regular object is larger, we must make sure that we use the
1169 larger size. This problematic case can always be avoided in C,
1170 but it must be handled correctly when using Fortran shared
1171 libraries.
1173 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1174 likewise for OLDDYNCOMMON and OLDDEF.
1176 Note that this test is just a heuristic, and that it is quite
1177 possible to have an uninitialized symbol in a shared object which
1178 is really a definition, rather than a common symbol. This could
1179 lead to some minor confusion when the symbol really is a common
1180 symbol in some regular object. However, I think it will be
1181 harmless. */
1183 if (newdyn
1184 && newdef
1185 && !newweak
1186 && (sec->flags & SEC_ALLOC) != 0
1187 && (sec->flags & SEC_LOAD) == 0
1188 && sym->st_size > 0
1189 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1190 newdyncommon = TRUE;
1191 else
1192 newdyncommon = FALSE;
1194 if (olddyn
1195 && olddef
1196 && h->root.type == bfd_link_hash_defined
1197 && h->def_dynamic
1198 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1199 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1200 && h->size > 0
1201 && h->type != STT_FUNC)
1202 olddyncommon = TRUE;
1203 else
1204 olddyncommon = FALSE;
1206 /* We now know everything about the old and new symbols. We ask the
1207 backend to check if we can merge them. */
1208 bed = get_elf_backend_data (abfd);
1209 if (bed->merge_symbol
1210 && !bed->merge_symbol (info, sym_hash, h, sym, psec, pvalue,
1211 pold_alignment, skip, override,
1212 type_change_ok, size_change_ok,
1213 &newdyn, &newdef, &newdyncommon, &newweak,
1214 abfd, &sec,
1215 &olddyn, &olddef, &olddyncommon, &oldweak,
1216 oldbfd, &oldsec))
1217 return FALSE;
1219 /* If both the old and the new symbols look like common symbols in a
1220 dynamic object, set the size of the symbol to the larger of the
1221 two. */
1223 if (olddyncommon
1224 && newdyncommon
1225 && sym->st_size != h->size)
1227 /* Since we think we have two common symbols, issue a multiple
1228 common warning if desired. Note that we only warn if the
1229 size is different. If the size is the same, we simply let
1230 the old symbol override the new one as normally happens with
1231 symbols defined in dynamic objects. */
1233 if (! ((*info->callbacks->multiple_common)
1234 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1235 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1236 return FALSE;
1238 if (sym->st_size > h->size)
1239 h->size = sym->st_size;
1241 *size_change_ok = TRUE;
1244 /* If we are looking at a dynamic object, and we have found a
1245 definition, we need to see if the symbol was already defined by
1246 some other object. If so, we want to use the existing
1247 definition, and we do not want to report a multiple symbol
1248 definition error; we do this by clobbering *PSEC to be
1249 bfd_und_section_ptr.
1251 We treat a common symbol as a definition if the symbol in the
1252 shared library is a function, since common symbols always
1253 represent variables; this can cause confusion in principle, but
1254 any such confusion would seem to indicate an erroneous program or
1255 shared library. We also permit a common symbol in a regular
1256 object to override a weak symbol in a shared object. */
1258 if (newdyn
1259 && newdef
1260 && (olddef
1261 || (h->root.type == bfd_link_hash_common
1262 && (newweak
1263 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1265 *override = TRUE;
1266 newdef = FALSE;
1267 newdyncommon = FALSE;
1269 *psec = sec = bfd_und_section_ptr;
1270 *size_change_ok = TRUE;
1272 /* If we get here when the old symbol is a common symbol, then
1273 we are explicitly letting it override a weak symbol or
1274 function in a dynamic object, and we don't want to warn about
1275 a type change. If the old symbol is a defined symbol, a type
1276 change warning may still be appropriate. */
1278 if (h->root.type == bfd_link_hash_common)
1279 *type_change_ok = TRUE;
1282 /* Handle the special case of an old common symbol merging with a
1283 new symbol which looks like a common symbol in a shared object.
1284 We change *PSEC and *PVALUE to make the new symbol look like a
1285 common symbol, and let _bfd_generic_link_add_one_symbol do the
1286 right thing. */
1288 if (newdyncommon
1289 && h->root.type == bfd_link_hash_common)
1291 *override = TRUE;
1292 newdef = FALSE;
1293 newdyncommon = FALSE;
1294 *pvalue = sym->st_size;
1295 *psec = sec = bed->common_section (oldsec);
1296 *size_change_ok = TRUE;
1299 /* Skip weak definitions of symbols that are already defined. */
1300 if (newdef && olddef && newweak)
1301 *skip = TRUE;
1303 /* If the old symbol is from a dynamic object, and the new symbol is
1304 a definition which is not from a dynamic object, then the new
1305 symbol overrides the old symbol. Symbols from regular files
1306 always take precedence over symbols from dynamic objects, even if
1307 they are defined after the dynamic object in the link.
1309 As above, we again permit a common symbol in a regular object to
1310 override a definition in a shared object if the shared object
1311 symbol is a function or is weak. */
1313 flip = NULL;
1314 if (!newdyn
1315 && (newdef
1316 || (bfd_is_com_section (sec)
1317 && (oldweak
1318 || h->type == STT_FUNC)))
1319 && olddyn
1320 && olddef
1321 && h->def_dynamic)
1323 /* Change the hash table entry to undefined, and let
1324 _bfd_generic_link_add_one_symbol do the right thing with the
1325 new definition. */
1327 h->root.type = bfd_link_hash_undefined;
1328 h->root.u.undef.abfd = h->root.u.def.section->owner;
1329 *size_change_ok = TRUE;
1331 olddef = FALSE;
1332 olddyncommon = FALSE;
1334 /* We again permit a type change when a common symbol may be
1335 overriding a function. */
1337 if (bfd_is_com_section (sec))
1338 *type_change_ok = TRUE;
1340 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1341 flip = *sym_hash;
1342 else
1343 /* This union may have been set to be non-NULL when this symbol
1344 was seen in a dynamic object. We must force the union to be
1345 NULL, so that it is correct for a regular symbol. */
1346 h->verinfo.vertree = NULL;
1349 /* Handle the special case of a new common symbol merging with an
1350 old symbol that looks like it might be a common symbol defined in
1351 a shared object. Note that we have already handled the case in
1352 which a new common symbol should simply override the definition
1353 in the shared library. */
1355 if (! newdyn
1356 && bfd_is_com_section (sec)
1357 && olddyncommon)
1359 /* It would be best if we could set the hash table entry to a
1360 common symbol, but we don't know what to use for the section
1361 or the alignment. */
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 the presumed common symbol in the dynamic object is
1368 larger, pretend that the new symbol has its size. */
1370 if (h->size > *pvalue)
1371 *pvalue = h->size;
1373 /* We need to remember the alignment required by the symbol
1374 in the dynamic object. */
1375 BFD_ASSERT (pold_alignment);
1376 *pold_alignment = h->root.u.def.section->alignment_power;
1378 olddef = FALSE;
1379 olddyncommon = FALSE;
1381 h->root.type = bfd_link_hash_undefined;
1382 h->root.u.undef.abfd = h->root.u.def.section->owner;
1384 *size_change_ok = TRUE;
1385 *type_change_ok = TRUE;
1387 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1388 flip = *sym_hash;
1389 else
1390 h->verinfo.vertree = NULL;
1393 if (flip != NULL)
1395 /* Handle the case where we had a versioned symbol in a dynamic
1396 library and now find a definition in a normal object. In this
1397 case, we make the versioned symbol point to the normal one. */
1398 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1399 flip->root.type = h->root.type;
1400 h->root.type = bfd_link_hash_indirect;
1401 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1402 (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1403 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1404 if (h->def_dynamic)
1406 h->def_dynamic = 0;
1407 flip->ref_dynamic = 1;
1411 return TRUE;
1414 /* This function is called to create an indirect symbol from the
1415 default for the symbol with the default version if needed. The
1416 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1417 set DYNSYM if the new indirect symbol is dynamic. */
1419 bfd_boolean
1420 _bfd_elf_add_default_symbol (bfd *abfd,
1421 struct bfd_link_info *info,
1422 struct elf_link_hash_entry *h,
1423 const char *name,
1424 Elf_Internal_Sym *sym,
1425 asection **psec,
1426 bfd_vma *value,
1427 bfd_boolean *dynsym,
1428 bfd_boolean override)
1430 bfd_boolean type_change_ok;
1431 bfd_boolean size_change_ok;
1432 bfd_boolean skip;
1433 char *shortname;
1434 struct elf_link_hash_entry *hi;
1435 struct bfd_link_hash_entry *bh;
1436 const struct elf_backend_data *bed;
1437 bfd_boolean collect;
1438 bfd_boolean dynamic;
1439 char *p;
1440 size_t len, shortlen;
1441 asection *sec;
1443 /* If this symbol has a version, and it is the default version, we
1444 create an indirect symbol from the default name to the fully
1445 decorated name. This will cause external references which do not
1446 specify a version to be bound to this version of the symbol. */
1447 p = strchr (name, ELF_VER_CHR);
1448 if (p == NULL || p[1] != ELF_VER_CHR)
1449 return TRUE;
1451 if (override)
1453 /* We are overridden by an old definition. We need to check if we
1454 need to create the indirect symbol from the default name. */
1455 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1456 FALSE, FALSE);
1457 BFD_ASSERT (hi != NULL);
1458 if (hi == h)
1459 return TRUE;
1460 while (hi->root.type == bfd_link_hash_indirect
1461 || hi->root.type == bfd_link_hash_warning)
1463 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1464 if (hi == h)
1465 return TRUE;
1469 bed = get_elf_backend_data (abfd);
1470 collect = bed->collect;
1471 dynamic = (abfd->flags & DYNAMIC) != 0;
1473 shortlen = p - name;
1474 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1475 if (shortname == NULL)
1476 return FALSE;
1477 memcpy (shortname, name, shortlen);
1478 shortname[shortlen] = '\0';
1480 /* We are going to create a new symbol. Merge it with any existing
1481 symbol with this name. For the purposes of the merge, act as
1482 though we were defining the symbol we just defined, although we
1483 actually going to define an indirect symbol. */
1484 type_change_ok = FALSE;
1485 size_change_ok = FALSE;
1486 sec = *psec;
1487 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1488 NULL, &hi, &skip, &override,
1489 &type_change_ok, &size_change_ok))
1490 return FALSE;
1492 if (skip)
1493 goto nondefault;
1495 if (! override)
1497 bh = &hi->root;
1498 if (! (_bfd_generic_link_add_one_symbol
1499 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1500 0, name, FALSE, collect, &bh)))
1501 return FALSE;
1502 hi = (struct elf_link_hash_entry *) bh;
1504 else
1506 /* In this case the symbol named SHORTNAME is overriding the
1507 indirect symbol we want to add. We were planning on making
1508 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1509 is the name without a version. NAME is the fully versioned
1510 name, and it is the default version.
1512 Overriding means that we already saw a definition for the
1513 symbol SHORTNAME in a regular object, and it is overriding
1514 the symbol defined in the dynamic object.
1516 When this happens, we actually want to change NAME, the
1517 symbol we just added, to refer to SHORTNAME. This will cause
1518 references to NAME in the shared object to become references
1519 to SHORTNAME in the regular object. This is what we expect
1520 when we override a function in a shared object: that the
1521 references in the shared object will be mapped to the
1522 definition in the regular object. */
1524 while (hi->root.type == bfd_link_hash_indirect
1525 || hi->root.type == bfd_link_hash_warning)
1526 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1528 h->root.type = bfd_link_hash_indirect;
1529 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1530 if (h->def_dynamic)
1532 h->def_dynamic = 0;
1533 hi->ref_dynamic = 1;
1534 if (hi->ref_regular
1535 || hi->def_regular)
1537 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1538 return FALSE;
1542 /* Now set HI to H, so that the following code will set the
1543 other fields correctly. */
1544 hi = h;
1547 /* If there is a duplicate definition somewhere, then HI may not
1548 point to an indirect symbol. We will have reported an error to
1549 the user in that case. */
1551 if (hi->root.type == bfd_link_hash_indirect)
1553 struct elf_link_hash_entry *ht;
1555 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1556 (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
1558 /* See if the new flags lead us to realize that the symbol must
1559 be dynamic. */
1560 if (! *dynsym)
1562 if (! dynamic)
1564 if (info->shared
1565 || hi->ref_dynamic)
1566 *dynsym = TRUE;
1568 else
1570 if (hi->ref_regular)
1571 *dynsym = TRUE;
1576 /* We also need to define an indirection from the nondefault version
1577 of the symbol. */
1579 nondefault:
1580 len = strlen (name);
1581 shortname = bfd_hash_allocate (&info->hash->table, len);
1582 if (shortname == NULL)
1583 return FALSE;
1584 memcpy (shortname, name, shortlen);
1585 memcpy (shortname + shortlen, p + 1, len - shortlen);
1587 /* Once again, merge with any existing symbol. */
1588 type_change_ok = FALSE;
1589 size_change_ok = FALSE;
1590 sec = *psec;
1591 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1592 NULL, &hi, &skip, &override,
1593 &type_change_ok, &size_change_ok))
1594 return FALSE;
1596 if (skip)
1597 return TRUE;
1599 if (override)
1601 /* Here SHORTNAME is a versioned name, so we don't expect to see
1602 the type of override we do in the case above unless it is
1603 overridden by a versioned definition. */
1604 if (hi->root.type != bfd_link_hash_defined
1605 && hi->root.type != bfd_link_hash_defweak)
1606 (*_bfd_error_handler)
1607 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1608 abfd, shortname);
1610 else
1612 bh = &hi->root;
1613 if (! (_bfd_generic_link_add_one_symbol
1614 (info, abfd, shortname, BSF_INDIRECT,
1615 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1616 return FALSE;
1617 hi = (struct elf_link_hash_entry *) bh;
1619 /* If there is a duplicate definition somewhere, then HI may not
1620 point to an indirect symbol. We will have reported an error
1621 to the user in that case. */
1623 if (hi->root.type == bfd_link_hash_indirect)
1625 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
1627 /* See if the new flags lead us to realize that the symbol
1628 must be dynamic. */
1629 if (! *dynsym)
1631 if (! dynamic)
1633 if (info->shared
1634 || hi->ref_dynamic)
1635 *dynsym = TRUE;
1637 else
1639 if (hi->ref_regular)
1640 *dynsym = TRUE;
1646 return TRUE;
1649 /* This routine is used to export all defined symbols into the dynamic
1650 symbol table. It is called via elf_link_hash_traverse. */
1652 bfd_boolean
1653 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1655 struct elf_info_failed *eif = data;
1657 /* Ignore this if we won't export it. */
1658 if (!eif->info->export_dynamic && !h->dynamic)
1659 return TRUE;
1661 /* Ignore indirect symbols. These are added by the versioning code. */
1662 if (h->root.type == bfd_link_hash_indirect)
1663 return TRUE;
1665 if (h->root.type == bfd_link_hash_warning)
1666 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1668 if (h->dynindx == -1
1669 && (h->def_regular
1670 || h->ref_regular))
1672 struct bfd_elf_version_tree *t;
1673 struct bfd_elf_version_expr *d;
1675 for (t = eif->verdefs; t != NULL; t = t->next)
1677 if (t->globals.list != NULL)
1679 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1680 if (d != NULL)
1681 goto doit;
1684 if (t->locals.list != NULL)
1686 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1687 if (d != NULL)
1688 return TRUE;
1692 if (!eif->verdefs)
1694 doit:
1695 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1697 eif->failed = TRUE;
1698 return FALSE;
1703 return TRUE;
1706 /* Look through the symbols which are defined in other shared
1707 libraries and referenced here. Update the list of version
1708 dependencies. This will be put into the .gnu.version_r section.
1709 This function is called via elf_link_hash_traverse. */
1711 bfd_boolean
1712 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1713 void *data)
1715 struct elf_find_verdep_info *rinfo = data;
1716 Elf_Internal_Verneed *t;
1717 Elf_Internal_Vernaux *a;
1718 bfd_size_type amt;
1720 if (h->root.type == bfd_link_hash_warning)
1721 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1723 /* We only care about symbols defined in shared objects with version
1724 information. */
1725 if (!h->def_dynamic
1726 || h->def_regular
1727 || h->dynindx == -1
1728 || h->verinfo.verdef == NULL)
1729 return TRUE;
1731 /* See if we already know about this version. */
1732 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1734 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1735 continue;
1737 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1738 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1739 return TRUE;
1741 break;
1744 /* This is a new version. Add it to tree we are building. */
1746 if (t == NULL)
1748 amt = sizeof *t;
1749 t = bfd_zalloc (rinfo->output_bfd, amt);
1750 if (t == NULL)
1752 rinfo->failed = TRUE;
1753 return FALSE;
1756 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1757 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1758 elf_tdata (rinfo->output_bfd)->verref = t;
1761 amt = sizeof *a;
1762 a = bfd_zalloc (rinfo->output_bfd, amt);
1764 /* Note that we are copying a string pointer here, and testing it
1765 above. If bfd_elf_string_from_elf_section is ever changed to
1766 discard the string data when low in memory, this will have to be
1767 fixed. */
1768 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1770 a->vna_flags = h->verinfo.verdef->vd_flags;
1771 a->vna_nextptr = t->vn_auxptr;
1773 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1774 ++rinfo->vers;
1776 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1778 t->vn_auxptr = a;
1780 return TRUE;
1783 /* Figure out appropriate versions for all the symbols. We may not
1784 have the version number script until we have read all of the input
1785 files, so until that point we don't know which symbols should be
1786 local. This function is called via elf_link_hash_traverse. */
1788 bfd_boolean
1789 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1791 struct elf_assign_sym_version_info *sinfo;
1792 struct bfd_link_info *info;
1793 const struct elf_backend_data *bed;
1794 struct elf_info_failed eif;
1795 char *p;
1796 bfd_size_type amt;
1798 sinfo = data;
1799 info = sinfo->info;
1801 if (h->root.type == bfd_link_hash_warning)
1802 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1804 /* Fix the symbol flags. */
1805 eif.failed = FALSE;
1806 eif.info = info;
1807 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1809 if (eif.failed)
1810 sinfo->failed = TRUE;
1811 return FALSE;
1814 /* We only need version numbers for symbols defined in regular
1815 objects. */
1816 if (!h->def_regular)
1817 return TRUE;
1819 bed = get_elf_backend_data (sinfo->output_bfd);
1820 p = strchr (h->root.root.string, ELF_VER_CHR);
1821 if (p != NULL && h->verinfo.vertree == NULL)
1823 struct bfd_elf_version_tree *t;
1824 bfd_boolean hidden;
1826 hidden = TRUE;
1828 /* There are two consecutive ELF_VER_CHR characters if this is
1829 not a hidden symbol. */
1830 ++p;
1831 if (*p == ELF_VER_CHR)
1833 hidden = FALSE;
1834 ++p;
1837 /* If there is no version string, we can just return out. */
1838 if (*p == '\0')
1840 if (hidden)
1841 h->hidden = 1;
1842 return TRUE;
1845 /* Look for the version. If we find it, it is no longer weak. */
1846 for (t = sinfo->verdefs; t != NULL; t = t->next)
1848 if (strcmp (t->name, p) == 0)
1850 size_t len;
1851 char *alc;
1852 struct bfd_elf_version_expr *d;
1854 len = p - h->root.root.string;
1855 alc = bfd_malloc (len);
1856 if (alc == NULL)
1857 return FALSE;
1858 memcpy (alc, h->root.root.string, len - 1);
1859 alc[len - 1] = '\0';
1860 if (alc[len - 2] == ELF_VER_CHR)
1861 alc[len - 2] = '\0';
1863 h->verinfo.vertree = t;
1864 t->used = TRUE;
1865 d = NULL;
1867 if (t->globals.list != NULL)
1868 d = (*t->match) (&t->globals, NULL, alc);
1870 /* See if there is anything to force this symbol to
1871 local scope. */
1872 if (d == NULL && t->locals.list != NULL)
1874 d = (*t->match) (&t->locals, NULL, alc);
1875 if (d != NULL
1876 && h->dynindx != -1
1877 && ! info->export_dynamic)
1878 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1881 free (alc);
1882 break;
1886 /* If we are building an application, we need to create a
1887 version node for this version. */
1888 if (t == NULL && info->executable)
1890 struct bfd_elf_version_tree **pp;
1891 int version_index;
1893 /* If we aren't going to export this symbol, we don't need
1894 to worry about it. */
1895 if (h->dynindx == -1)
1896 return TRUE;
1898 amt = sizeof *t;
1899 t = bfd_zalloc (sinfo->output_bfd, amt);
1900 if (t == NULL)
1902 sinfo->failed = TRUE;
1903 return FALSE;
1906 t->name = p;
1907 t->name_indx = (unsigned int) -1;
1908 t->used = TRUE;
1910 version_index = 1;
1911 /* Don't count anonymous version tag. */
1912 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1913 version_index = 0;
1914 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1915 ++version_index;
1916 t->vernum = version_index;
1918 *pp = t;
1920 h->verinfo.vertree = t;
1922 else if (t == NULL)
1924 /* We could not find the version for a symbol when
1925 generating a shared archive. Return an error. */
1926 (*_bfd_error_handler)
1927 (_("%B: undefined versioned symbol name %s"),
1928 sinfo->output_bfd, h->root.root.string);
1929 bfd_set_error (bfd_error_bad_value);
1930 sinfo->failed = TRUE;
1931 return FALSE;
1934 if (hidden)
1935 h->hidden = 1;
1938 /* If we don't have a version for this symbol, see if we can find
1939 something. */
1940 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1942 struct bfd_elf_version_tree *t;
1943 struct bfd_elf_version_tree *local_ver;
1944 struct bfd_elf_version_expr *d;
1946 /* See if can find what version this symbol is in. If the
1947 symbol is supposed to be local, then don't actually register
1948 it. */
1949 local_ver = NULL;
1950 for (t = sinfo->verdefs; t != NULL; t = t->next)
1952 if (t->globals.list != NULL)
1954 bfd_boolean matched;
1956 matched = FALSE;
1957 d = NULL;
1958 while ((d = (*t->match) (&t->globals, d,
1959 h->root.root.string)) != NULL)
1960 if (d->symver)
1961 matched = TRUE;
1962 else
1964 /* There is a version without definition. Make
1965 the symbol the default definition for this
1966 version. */
1967 h->verinfo.vertree = t;
1968 local_ver = NULL;
1969 d->script = 1;
1970 break;
1972 if (d != NULL)
1973 break;
1974 else if (matched)
1975 /* There is no undefined version for this symbol. Hide the
1976 default one. */
1977 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1980 if (t->locals.list != NULL)
1982 d = NULL;
1983 while ((d = (*t->match) (&t->locals, d,
1984 h->root.root.string)) != NULL)
1986 local_ver = t;
1987 /* If the match is "*", keep looking for a more
1988 explicit, perhaps even global, match.
1989 XXX: Shouldn't this be !d->wildcard instead? */
1990 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1991 break;
1994 if (d != NULL)
1995 break;
1999 if (local_ver != NULL)
2001 h->verinfo.vertree = local_ver;
2002 if (h->dynindx != -1
2003 && ! info->export_dynamic)
2005 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
2010 return TRUE;
2013 /* Read and swap the relocs from the section indicated by SHDR. This
2014 may be either a REL or a RELA section. The relocations are
2015 translated into RELA relocations and stored in INTERNAL_RELOCS,
2016 which should have already been allocated to contain enough space.
2017 The EXTERNAL_RELOCS are a buffer where the external form of the
2018 relocations should be stored.
2020 Returns FALSE if something goes wrong. */
2022 static bfd_boolean
2023 elf_link_read_relocs_from_section (bfd *abfd,
2024 asection *sec,
2025 Elf_Internal_Shdr *shdr,
2026 void *external_relocs,
2027 Elf_Internal_Rela *internal_relocs)
2029 const struct elf_backend_data *bed;
2030 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
2031 const bfd_byte *erela;
2032 const bfd_byte *erelaend;
2033 Elf_Internal_Rela *irela;
2034 Elf_Internal_Shdr *symtab_hdr;
2035 size_t nsyms;
2037 /* Position ourselves at the start of the section. */
2038 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2039 return FALSE;
2041 /* Read the relocations. */
2042 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
2043 return FALSE;
2045 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2046 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
2048 bed = get_elf_backend_data (abfd);
2050 /* Convert the external relocations to the internal format. */
2051 if (shdr->sh_entsize == bed->s->sizeof_rel)
2052 swap_in = bed->s->swap_reloc_in;
2053 else if (shdr->sh_entsize == bed->s->sizeof_rela)
2054 swap_in = bed->s->swap_reloca_in;
2055 else
2057 bfd_set_error (bfd_error_wrong_format);
2058 return FALSE;
2061 erela = external_relocs;
2062 erelaend = erela + shdr->sh_size;
2063 irela = internal_relocs;
2064 while (erela < erelaend)
2066 bfd_vma r_symndx;
2068 (*swap_in) (abfd, erela, irela);
2069 r_symndx = ELF32_R_SYM (irela->r_info);
2070 if (bed->s->arch_size == 64)
2071 r_symndx >>= 24;
2072 if ((size_t) r_symndx >= nsyms)
2074 (*_bfd_error_handler)
2075 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
2076 " for offset 0x%lx in section `%A'"),
2077 abfd, sec,
2078 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
2079 bfd_set_error (bfd_error_bad_value);
2080 return FALSE;
2082 irela += bed->s->int_rels_per_ext_rel;
2083 erela += shdr->sh_entsize;
2086 return TRUE;
2089 /* Read and swap the relocs for a section O. They may have been
2090 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2091 not NULL, they are used as buffers to read into. They are known to
2092 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2093 the return value is allocated using either malloc or bfd_alloc,
2094 according to the KEEP_MEMORY argument. If O has two relocation
2095 sections (both REL and RELA relocations), then the REL_HDR
2096 relocations will appear first in INTERNAL_RELOCS, followed by the
2097 REL_HDR2 relocations. */
2099 Elf_Internal_Rela *
2100 _bfd_elf_link_read_relocs (bfd *abfd,
2101 asection *o,
2102 void *external_relocs,
2103 Elf_Internal_Rela *internal_relocs,
2104 bfd_boolean keep_memory)
2106 Elf_Internal_Shdr *rel_hdr;
2107 void *alloc1 = NULL;
2108 Elf_Internal_Rela *alloc2 = NULL;
2109 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2111 if (elf_section_data (o)->relocs != NULL)
2112 return elf_section_data (o)->relocs;
2114 if (o->reloc_count == 0)
2115 return NULL;
2117 rel_hdr = &elf_section_data (o)->rel_hdr;
2119 if (internal_relocs == NULL)
2121 bfd_size_type size;
2123 size = o->reloc_count;
2124 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2125 if (keep_memory)
2126 internal_relocs = bfd_alloc (abfd, size);
2127 else
2128 internal_relocs = alloc2 = bfd_malloc (size);
2129 if (internal_relocs == NULL)
2130 goto error_return;
2133 if (external_relocs == NULL)
2135 bfd_size_type size = rel_hdr->sh_size;
2137 if (elf_section_data (o)->rel_hdr2)
2138 size += elf_section_data (o)->rel_hdr2->sh_size;
2139 alloc1 = bfd_malloc (size);
2140 if (alloc1 == NULL)
2141 goto error_return;
2142 external_relocs = alloc1;
2145 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2146 external_relocs,
2147 internal_relocs))
2148 goto error_return;
2149 if (elf_section_data (o)->rel_hdr2
2150 && (!elf_link_read_relocs_from_section
2151 (abfd, o,
2152 elf_section_data (o)->rel_hdr2,
2153 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2154 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2155 * bed->s->int_rels_per_ext_rel))))
2156 goto error_return;
2158 /* Cache the results for next time, if we can. */
2159 if (keep_memory)
2160 elf_section_data (o)->relocs = internal_relocs;
2162 if (alloc1 != NULL)
2163 free (alloc1);
2165 /* Don't free alloc2, since if it was allocated we are passing it
2166 back (under the name of internal_relocs). */
2168 return internal_relocs;
2170 error_return:
2171 if (alloc1 != NULL)
2172 free (alloc1);
2173 if (alloc2 != NULL)
2174 free (alloc2);
2175 return NULL;
2178 /* Compute the size of, and allocate space for, REL_HDR which is the
2179 section header for a section containing relocations for O. */
2181 bfd_boolean
2182 _bfd_elf_link_size_reloc_section (bfd *abfd,
2183 Elf_Internal_Shdr *rel_hdr,
2184 asection *o)
2186 bfd_size_type reloc_count;
2187 bfd_size_type num_rel_hashes;
2189 /* Figure out how many relocations there will be. */
2190 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2191 reloc_count = elf_section_data (o)->rel_count;
2192 else
2193 reloc_count = elf_section_data (o)->rel_count2;
2195 num_rel_hashes = o->reloc_count;
2196 if (num_rel_hashes < reloc_count)
2197 num_rel_hashes = reloc_count;
2199 /* That allows us to calculate the size of the section. */
2200 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2202 /* The contents field must last into write_object_contents, so we
2203 allocate it with bfd_alloc rather than malloc. Also since we
2204 cannot be sure that the contents will actually be filled in,
2205 we zero the allocated space. */
2206 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2207 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2208 return FALSE;
2210 /* We only allocate one set of hash entries, so we only do it the
2211 first time we are called. */
2212 if (elf_section_data (o)->rel_hashes == NULL
2213 && num_rel_hashes)
2215 struct elf_link_hash_entry **p;
2217 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2218 if (p == NULL)
2219 return FALSE;
2221 elf_section_data (o)->rel_hashes = p;
2224 return TRUE;
2227 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2228 originated from the section given by INPUT_REL_HDR) to the
2229 OUTPUT_BFD. */
2231 bfd_boolean
2232 _bfd_elf_link_output_relocs (bfd *output_bfd,
2233 asection *input_section,
2234 Elf_Internal_Shdr *input_rel_hdr,
2235 Elf_Internal_Rela *internal_relocs,
2236 struct elf_link_hash_entry **rel_hash
2237 ATTRIBUTE_UNUSED)
2239 Elf_Internal_Rela *irela;
2240 Elf_Internal_Rela *irelaend;
2241 bfd_byte *erel;
2242 Elf_Internal_Shdr *output_rel_hdr;
2243 asection *output_section;
2244 unsigned int *rel_countp = NULL;
2245 const struct elf_backend_data *bed;
2246 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2248 output_section = input_section->output_section;
2249 output_rel_hdr = NULL;
2251 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2252 == input_rel_hdr->sh_entsize)
2254 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2255 rel_countp = &elf_section_data (output_section)->rel_count;
2257 else if (elf_section_data (output_section)->rel_hdr2
2258 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2259 == input_rel_hdr->sh_entsize))
2261 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2262 rel_countp = &elf_section_data (output_section)->rel_count2;
2264 else
2266 (*_bfd_error_handler)
2267 (_("%B: relocation size mismatch in %B section %A"),
2268 output_bfd, input_section->owner, input_section);
2269 bfd_set_error (bfd_error_wrong_object_format);
2270 return FALSE;
2273 bed = get_elf_backend_data (output_bfd);
2274 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2275 swap_out = bed->s->swap_reloc_out;
2276 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2277 swap_out = bed->s->swap_reloca_out;
2278 else
2279 abort ();
2281 erel = output_rel_hdr->contents;
2282 erel += *rel_countp * input_rel_hdr->sh_entsize;
2283 irela = internal_relocs;
2284 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2285 * bed->s->int_rels_per_ext_rel);
2286 while (irela < irelaend)
2288 (*swap_out) (output_bfd, irela, erel);
2289 irela += bed->s->int_rels_per_ext_rel;
2290 erel += input_rel_hdr->sh_entsize;
2293 /* Bump the counter, so that we know where to add the next set of
2294 relocations. */
2295 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2297 return TRUE;
2300 /* Make weak undefined symbols in PIE dynamic. */
2302 bfd_boolean
2303 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2304 struct elf_link_hash_entry *h)
2306 if (info->pie
2307 && h->dynindx == -1
2308 && h->root.type == bfd_link_hash_undefweak)
2309 return bfd_elf_link_record_dynamic_symbol (info, h);
2311 return TRUE;
2314 /* Fix up the flags for a symbol. This handles various cases which
2315 can only be fixed after all the input files are seen. This is
2316 currently called by both adjust_dynamic_symbol and
2317 assign_sym_version, which is unnecessary but perhaps more robust in
2318 the face of future changes. */
2320 bfd_boolean
2321 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2322 struct elf_info_failed *eif)
2324 const struct elf_backend_data *bed = NULL;
2326 /* If this symbol was mentioned in a non-ELF file, try to set
2327 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2328 permit a non-ELF file to correctly refer to a symbol defined in
2329 an ELF dynamic object. */
2330 if (h->non_elf)
2332 while (h->root.type == bfd_link_hash_indirect)
2333 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2335 if (h->root.type != bfd_link_hash_defined
2336 && h->root.type != bfd_link_hash_defweak)
2338 h->ref_regular = 1;
2339 h->ref_regular_nonweak = 1;
2341 else
2343 if (h->root.u.def.section->owner != NULL
2344 && (bfd_get_flavour (h->root.u.def.section->owner)
2345 == bfd_target_elf_flavour))
2347 h->ref_regular = 1;
2348 h->ref_regular_nonweak = 1;
2350 else
2351 h->def_regular = 1;
2354 if (h->dynindx == -1
2355 && (h->def_dynamic
2356 || h->ref_dynamic))
2358 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2360 eif->failed = TRUE;
2361 return FALSE;
2365 else
2367 /* Unfortunately, NON_ELF is only correct if the symbol
2368 was first seen in a non-ELF file. Fortunately, if the symbol
2369 was first seen in an ELF file, we're probably OK unless the
2370 symbol was defined in a non-ELF file. Catch that case here.
2371 FIXME: We're still in trouble if the symbol was first seen in
2372 a dynamic object, and then later in a non-ELF regular object. */
2373 if ((h->root.type == bfd_link_hash_defined
2374 || h->root.type == bfd_link_hash_defweak)
2375 && !h->def_regular
2376 && (h->root.u.def.section->owner != NULL
2377 ? (bfd_get_flavour (h->root.u.def.section->owner)
2378 != bfd_target_elf_flavour)
2379 : (bfd_is_abs_section (h->root.u.def.section)
2380 && !h->def_dynamic)))
2381 h->def_regular = 1;
2384 /* Backend specific symbol fixup. */
2385 if (elf_hash_table (eif->info)->dynobj)
2387 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2388 if (bed->elf_backend_fixup_symbol
2389 && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
2390 return FALSE;
2393 /* If this is a final link, and the symbol was defined as a common
2394 symbol in a regular object file, and there was no definition in
2395 any dynamic object, then the linker will have allocated space for
2396 the symbol in a common section but the DEF_REGULAR
2397 flag will not have been set. */
2398 if (h->root.type == bfd_link_hash_defined
2399 && !h->def_regular
2400 && h->ref_regular
2401 && !h->def_dynamic
2402 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2403 h->def_regular = 1;
2405 /* If -Bsymbolic was used (which means to bind references to global
2406 symbols to the definition within the shared object), and this
2407 symbol was defined in a regular object, then it actually doesn't
2408 need a PLT entry. Likewise, if the symbol has non-default
2409 visibility. If the symbol has hidden or internal visibility, we
2410 will force it local. */
2411 if (h->needs_plt
2412 && eif->info->shared
2413 && is_elf_hash_table (eif->info->hash)
2414 && (SYMBOLIC_BIND (eif->info, h)
2415 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2416 && h->def_regular)
2418 bfd_boolean force_local;
2420 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2421 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2422 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2425 /* If a weak undefined symbol has non-default visibility, we also
2426 hide it from the dynamic linker. */
2427 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2428 && h->root.type == bfd_link_hash_undefweak)
2430 const struct elf_backend_data *bed;
2431 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2432 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2435 /* If this is a weak defined symbol in a dynamic object, and we know
2436 the real definition in the dynamic object, copy interesting flags
2437 over to the real definition. */
2438 if (h->u.weakdef != NULL)
2440 struct elf_link_hash_entry *weakdef;
2442 weakdef = h->u.weakdef;
2443 if (h->root.type == bfd_link_hash_indirect)
2444 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2446 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2447 || h->root.type == bfd_link_hash_defweak);
2448 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2449 || weakdef->root.type == bfd_link_hash_defweak);
2450 BFD_ASSERT (weakdef->def_dynamic);
2452 /* If the real definition is defined by a regular object file,
2453 don't do anything special. See the longer description in
2454 _bfd_elf_adjust_dynamic_symbol, below. */
2455 if (weakdef->def_regular)
2456 h->u.weakdef = NULL;
2457 else
2458 (*bed->elf_backend_copy_indirect_symbol) (eif->info, weakdef,
2462 return TRUE;
2465 /* Make the backend pick a good value for a dynamic symbol. This is
2466 called via elf_link_hash_traverse, and also calls itself
2467 recursively. */
2469 bfd_boolean
2470 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2472 struct elf_info_failed *eif = data;
2473 bfd *dynobj;
2474 const struct elf_backend_data *bed;
2476 if (! is_elf_hash_table (eif->info->hash))
2477 return FALSE;
2479 if (h->root.type == bfd_link_hash_warning)
2481 h->got = elf_hash_table (eif->info)->init_got_offset;
2482 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2484 /* When warning symbols are created, they **replace** the "real"
2485 entry in the hash table, thus we never get to see the real
2486 symbol in a hash traversal. So look at it now. */
2487 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2490 /* Ignore indirect symbols. These are added by the versioning code. */
2491 if (h->root.type == bfd_link_hash_indirect)
2492 return TRUE;
2494 /* Fix the symbol flags. */
2495 if (! _bfd_elf_fix_symbol_flags (h, eif))
2496 return FALSE;
2498 /* If this symbol does not require a PLT entry, and it is not
2499 defined by a dynamic object, or is not referenced by a regular
2500 object, ignore it. We do have to handle a weak defined symbol,
2501 even if no regular object refers to it, if we decided to add it
2502 to the dynamic symbol table. FIXME: Do we normally need to worry
2503 about symbols which are defined by one dynamic object and
2504 referenced by another one? */
2505 if (!h->needs_plt
2506 && (h->def_regular
2507 || !h->def_dynamic
2508 || (!h->ref_regular
2509 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2511 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2512 return TRUE;
2515 /* If we've already adjusted this symbol, don't do it again. This
2516 can happen via a recursive call. */
2517 if (h->dynamic_adjusted)
2518 return TRUE;
2520 /* Don't look at this symbol again. Note that we must set this
2521 after checking the above conditions, because we may look at a
2522 symbol once, decide not to do anything, and then get called
2523 recursively later after REF_REGULAR is set below. */
2524 h->dynamic_adjusted = 1;
2526 /* If this is a weak definition, and we know a real definition, and
2527 the real symbol is not itself defined by a regular object file,
2528 then get a good value for the real definition. We handle the
2529 real symbol first, for the convenience of the backend routine.
2531 Note that there is a confusing case here. If the real definition
2532 is defined by a regular object file, we don't get the real symbol
2533 from the dynamic object, but we do get the weak symbol. If the
2534 processor backend uses a COPY reloc, then if some routine in the
2535 dynamic object changes the real symbol, we will not see that
2536 change in the corresponding weak symbol. This is the way other
2537 ELF linkers work as well, and seems to be a result of the shared
2538 library model.
2540 I will clarify this issue. Most SVR4 shared libraries define the
2541 variable _timezone and define timezone as a weak synonym. The
2542 tzset call changes _timezone. If you write
2543 extern int timezone;
2544 int _timezone = 5;
2545 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2546 you might expect that, since timezone is a synonym for _timezone,
2547 the same number will print both times. However, if the processor
2548 backend uses a COPY reloc, then actually timezone will be copied
2549 into your process image, and, since you define _timezone
2550 yourself, _timezone will not. Thus timezone and _timezone will
2551 wind up at different memory locations. The tzset call will set
2552 _timezone, leaving timezone unchanged. */
2554 if (h->u.weakdef != NULL)
2556 /* If we get to this point, we know there is an implicit
2557 reference by a regular object file via the weak symbol H.
2558 FIXME: Is this really true? What if the traversal finds
2559 H->U.WEAKDEF before it finds H? */
2560 h->u.weakdef->ref_regular = 1;
2562 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2563 return FALSE;
2566 /* If a symbol has no type and no size and does not require a PLT
2567 entry, then we are probably about to do the wrong thing here: we
2568 are probably going to create a COPY reloc for an empty object.
2569 This case can arise when a shared object is built with assembly
2570 code, and the assembly code fails to set the symbol type. */
2571 if (h->size == 0
2572 && h->type == STT_NOTYPE
2573 && !h->needs_plt)
2574 (*_bfd_error_handler)
2575 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2576 h->root.root.string);
2578 dynobj = elf_hash_table (eif->info)->dynobj;
2579 bed = get_elf_backend_data (dynobj);
2580 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2582 eif->failed = TRUE;
2583 return FALSE;
2586 return TRUE;
2589 /* Adjust all external symbols pointing into SEC_MERGE sections
2590 to reflect the object merging within the sections. */
2592 bfd_boolean
2593 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2595 asection *sec;
2597 if (h->root.type == bfd_link_hash_warning)
2598 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2600 if ((h->root.type == bfd_link_hash_defined
2601 || h->root.type == bfd_link_hash_defweak)
2602 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2603 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2605 bfd *output_bfd = data;
2607 h->root.u.def.value =
2608 _bfd_merged_section_offset (output_bfd,
2609 &h->root.u.def.section,
2610 elf_section_data (sec)->sec_info,
2611 h->root.u.def.value);
2614 return TRUE;
2617 /* Returns false if the symbol referred to by H should be considered
2618 to resolve local to the current module, and true if it should be
2619 considered to bind dynamically. */
2621 bfd_boolean
2622 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2623 struct bfd_link_info *info,
2624 bfd_boolean ignore_protected)
2626 bfd_boolean binding_stays_local_p;
2628 if (h == NULL)
2629 return FALSE;
2631 while (h->root.type == bfd_link_hash_indirect
2632 || h->root.type == bfd_link_hash_warning)
2633 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2635 /* If it was forced local, then clearly it's not dynamic. */
2636 if (h->dynindx == -1)
2637 return FALSE;
2638 if (h->forced_local)
2639 return FALSE;
2641 /* Identify the cases where name binding rules say that a
2642 visible symbol resolves locally. */
2643 binding_stays_local_p = info->executable || SYMBOLIC_BIND (info, h);
2645 switch (ELF_ST_VISIBILITY (h->other))
2647 case STV_INTERNAL:
2648 case STV_HIDDEN:
2649 return FALSE;
2651 case STV_PROTECTED:
2652 /* Proper resolution for function pointer equality may require
2653 that these symbols perhaps be resolved dynamically, even though
2654 we should be resolving them to the current module. */
2655 if (!ignore_protected || h->type != STT_FUNC)
2656 binding_stays_local_p = TRUE;
2657 break;
2659 default:
2660 break;
2663 /* If it isn't defined locally, then clearly it's dynamic. */
2664 if (!h->def_regular)
2665 return TRUE;
2667 /* Otherwise, the symbol is dynamic if binding rules don't tell
2668 us that it remains local. */
2669 return !binding_stays_local_p;
2672 /* Return true if the symbol referred to by H should be considered
2673 to resolve local to the current module, and false otherwise. Differs
2674 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2675 undefined symbols and weak symbols. */
2677 bfd_boolean
2678 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2679 struct bfd_link_info *info,
2680 bfd_boolean local_protected)
2682 /* If it's a local sym, of course we resolve locally. */
2683 if (h == NULL)
2684 return TRUE;
2686 /* Common symbols that become definitions don't get the DEF_REGULAR
2687 flag set, so test it first, and don't bail out. */
2688 if (ELF_COMMON_DEF_P (h))
2689 /* Do nothing. */;
2690 /* If we don't have a definition in a regular file, then we can't
2691 resolve locally. The sym is either undefined or dynamic. */
2692 else if (!h->def_regular)
2693 return FALSE;
2695 /* Forced local symbols resolve locally. */
2696 if (h->forced_local)
2697 return TRUE;
2699 /* As do non-dynamic symbols. */
2700 if (h->dynindx == -1)
2701 return TRUE;
2703 /* At this point, we know the symbol is defined and dynamic. In an
2704 executable it must resolve locally, likewise when building symbolic
2705 shared libraries. */
2706 if (info->executable || SYMBOLIC_BIND (info, h))
2707 return TRUE;
2709 /* Now deal with defined dynamic symbols in shared libraries. Ones
2710 with default visibility might not resolve locally. */
2711 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2712 return FALSE;
2714 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2715 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2716 return TRUE;
2718 /* STV_PROTECTED non-function symbols are local. */
2719 if (h->type != STT_FUNC)
2720 return TRUE;
2722 /* Function pointer equality tests may require that STV_PROTECTED
2723 symbols be treated as dynamic symbols, even when we know that the
2724 dynamic linker will resolve them locally. */
2725 return local_protected;
2728 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2729 aligned. Returns the first TLS output section. */
2731 struct bfd_section *
2732 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2734 struct bfd_section *sec, *tls;
2735 unsigned int align = 0;
2737 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2738 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2739 break;
2740 tls = sec;
2742 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2743 if (sec->alignment_power > align)
2744 align = sec->alignment_power;
2746 elf_hash_table (info)->tls_sec = tls;
2748 /* Ensure the alignment of the first section is the largest alignment,
2749 so that the tls segment starts aligned. */
2750 if (tls != NULL)
2751 tls->alignment_power = align;
2753 return tls;
2756 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2757 static bfd_boolean
2758 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2759 Elf_Internal_Sym *sym)
2761 const struct elf_backend_data *bed;
2763 /* Local symbols do not count, but target specific ones might. */
2764 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2765 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2766 return FALSE;
2768 /* Function symbols do not count. */
2769 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2770 return FALSE;
2772 /* If the section is undefined, then so is the symbol. */
2773 if (sym->st_shndx == SHN_UNDEF)
2774 return FALSE;
2776 /* If the symbol is defined in the common section, then
2777 it is a common definition and so does not count. */
2778 bed = get_elf_backend_data (abfd);
2779 if (bed->common_definition (sym))
2780 return FALSE;
2782 /* If the symbol is in a target specific section then we
2783 must rely upon the backend to tell us what it is. */
2784 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2785 /* FIXME - this function is not coded yet:
2787 return _bfd_is_global_symbol_definition (abfd, sym);
2789 Instead for now assume that the definition is not global,
2790 Even if this is wrong, at least the linker will behave
2791 in the same way that it used to do. */
2792 return FALSE;
2794 return TRUE;
2797 /* Search the symbol table of the archive element of the archive ABFD
2798 whose archive map contains a mention of SYMDEF, and determine if
2799 the symbol is defined in this element. */
2800 static bfd_boolean
2801 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2803 Elf_Internal_Shdr * hdr;
2804 bfd_size_type symcount;
2805 bfd_size_type extsymcount;
2806 bfd_size_type extsymoff;
2807 Elf_Internal_Sym *isymbuf;
2808 Elf_Internal_Sym *isym;
2809 Elf_Internal_Sym *isymend;
2810 bfd_boolean result;
2812 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2813 if (abfd == NULL)
2814 return FALSE;
2816 if (! bfd_check_format (abfd, bfd_object))
2817 return FALSE;
2819 /* If we have already included the element containing this symbol in the
2820 link then we do not need to include it again. Just claim that any symbol
2821 it contains is not a definition, so that our caller will not decide to
2822 (re)include this element. */
2823 if (abfd->archive_pass)
2824 return FALSE;
2826 /* Select the appropriate symbol table. */
2827 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2828 hdr = &elf_tdata (abfd)->symtab_hdr;
2829 else
2830 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2832 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2834 /* The sh_info field of the symtab header tells us where the
2835 external symbols start. We don't care about the local symbols. */
2836 if (elf_bad_symtab (abfd))
2838 extsymcount = symcount;
2839 extsymoff = 0;
2841 else
2843 extsymcount = symcount - hdr->sh_info;
2844 extsymoff = hdr->sh_info;
2847 if (extsymcount == 0)
2848 return FALSE;
2850 /* Read in the symbol table. */
2851 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2852 NULL, NULL, NULL);
2853 if (isymbuf == NULL)
2854 return FALSE;
2856 /* Scan the symbol table looking for SYMDEF. */
2857 result = FALSE;
2858 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2860 const char *name;
2862 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2863 isym->st_name);
2864 if (name == NULL)
2865 break;
2867 if (strcmp (name, symdef->name) == 0)
2869 result = is_global_data_symbol_definition (abfd, isym);
2870 break;
2874 free (isymbuf);
2876 return result;
2879 /* Add an entry to the .dynamic table. */
2881 bfd_boolean
2882 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2883 bfd_vma tag,
2884 bfd_vma val)
2886 struct elf_link_hash_table *hash_table;
2887 const struct elf_backend_data *bed;
2888 asection *s;
2889 bfd_size_type newsize;
2890 bfd_byte *newcontents;
2891 Elf_Internal_Dyn dyn;
2893 hash_table = elf_hash_table (info);
2894 if (! is_elf_hash_table (hash_table))
2895 return FALSE;
2897 bed = get_elf_backend_data (hash_table->dynobj);
2898 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2899 BFD_ASSERT (s != NULL);
2901 newsize = s->size + bed->s->sizeof_dyn;
2902 newcontents = bfd_realloc (s->contents, newsize);
2903 if (newcontents == NULL)
2904 return FALSE;
2906 dyn.d_tag = tag;
2907 dyn.d_un.d_val = val;
2908 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2910 s->size = newsize;
2911 s->contents = newcontents;
2913 return TRUE;
2916 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2917 otherwise just check whether one already exists. Returns -1 on error,
2918 1 if a DT_NEEDED tag already exists, and 0 on success. */
2920 static int
2921 elf_add_dt_needed_tag (bfd *abfd,
2922 struct bfd_link_info *info,
2923 const char *soname,
2924 bfd_boolean do_it)
2926 struct elf_link_hash_table *hash_table;
2927 bfd_size_type oldsize;
2928 bfd_size_type strindex;
2930 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2931 return -1;
2933 hash_table = elf_hash_table (info);
2934 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2935 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2936 if (strindex == (bfd_size_type) -1)
2937 return -1;
2939 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2941 asection *sdyn;
2942 const struct elf_backend_data *bed;
2943 bfd_byte *extdyn;
2945 bed = get_elf_backend_data (hash_table->dynobj);
2946 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2947 if (sdyn != NULL)
2948 for (extdyn = sdyn->contents;
2949 extdyn < sdyn->contents + sdyn->size;
2950 extdyn += bed->s->sizeof_dyn)
2952 Elf_Internal_Dyn dyn;
2954 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2955 if (dyn.d_tag == DT_NEEDED
2956 && dyn.d_un.d_val == strindex)
2958 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2959 return 1;
2964 if (do_it)
2966 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2967 return -1;
2969 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2970 return -1;
2972 else
2973 /* We were just checking for existence of the tag. */
2974 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2976 return 0;
2979 /* Sort symbol by value and section. */
2980 static int
2981 elf_sort_symbol (const void *arg1, const void *arg2)
2983 const struct elf_link_hash_entry *h1;
2984 const struct elf_link_hash_entry *h2;
2985 bfd_signed_vma vdiff;
2987 h1 = *(const struct elf_link_hash_entry **) arg1;
2988 h2 = *(const struct elf_link_hash_entry **) arg2;
2989 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2990 if (vdiff != 0)
2991 return vdiff > 0 ? 1 : -1;
2992 else
2994 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2995 if (sdiff != 0)
2996 return sdiff > 0 ? 1 : -1;
2998 return 0;
3001 /* This function is used to adjust offsets into .dynstr for
3002 dynamic symbols. This is called via elf_link_hash_traverse. */
3004 static bfd_boolean
3005 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3007 struct elf_strtab_hash *dynstr = data;
3009 if (h->root.type == bfd_link_hash_warning)
3010 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3012 if (h->dynindx != -1)
3013 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3014 return TRUE;
3017 /* Assign string offsets in .dynstr, update all structures referencing
3018 them. */
3020 static bfd_boolean
3021 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3023 struct elf_link_hash_table *hash_table = elf_hash_table (info);
3024 struct elf_link_local_dynamic_entry *entry;
3025 struct elf_strtab_hash *dynstr = hash_table->dynstr;
3026 bfd *dynobj = hash_table->dynobj;
3027 asection *sdyn;
3028 bfd_size_type size;
3029 const struct elf_backend_data *bed;
3030 bfd_byte *extdyn;
3032 _bfd_elf_strtab_finalize (dynstr);
3033 size = _bfd_elf_strtab_size (dynstr);
3035 bed = get_elf_backend_data (dynobj);
3036 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3037 BFD_ASSERT (sdyn != NULL);
3039 /* Update all .dynamic entries referencing .dynstr strings. */
3040 for (extdyn = sdyn->contents;
3041 extdyn < sdyn->contents + sdyn->size;
3042 extdyn += bed->s->sizeof_dyn)
3044 Elf_Internal_Dyn dyn;
3046 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3047 switch (dyn.d_tag)
3049 case DT_STRSZ:
3050 dyn.d_un.d_val = size;
3051 break;
3052 case DT_NEEDED:
3053 case DT_SONAME:
3054 case DT_RPATH:
3055 case DT_RUNPATH:
3056 case DT_FILTER:
3057 case DT_AUXILIARY:
3058 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3059 break;
3060 default:
3061 continue;
3063 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3066 /* Now update local dynamic symbols. */
3067 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3068 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3069 entry->isym.st_name);
3071 /* And the rest of dynamic symbols. */
3072 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3074 /* Adjust version definitions. */
3075 if (elf_tdata (output_bfd)->cverdefs)
3077 asection *s;
3078 bfd_byte *p;
3079 bfd_size_type i;
3080 Elf_Internal_Verdef def;
3081 Elf_Internal_Verdaux defaux;
3083 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3084 p = s->contents;
3087 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3088 &def);
3089 p += sizeof (Elf_External_Verdef);
3090 if (def.vd_aux != sizeof (Elf_External_Verdef))
3091 continue;
3092 for (i = 0; i < def.vd_cnt; ++i)
3094 _bfd_elf_swap_verdaux_in (output_bfd,
3095 (Elf_External_Verdaux *) p, &defaux);
3096 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3097 defaux.vda_name);
3098 _bfd_elf_swap_verdaux_out (output_bfd,
3099 &defaux, (Elf_External_Verdaux *) p);
3100 p += sizeof (Elf_External_Verdaux);
3103 while (def.vd_next);
3106 /* Adjust version references. */
3107 if (elf_tdata (output_bfd)->verref)
3109 asection *s;
3110 bfd_byte *p;
3111 bfd_size_type i;
3112 Elf_Internal_Verneed need;
3113 Elf_Internal_Vernaux needaux;
3115 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3116 p = s->contents;
3119 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3120 &need);
3121 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3122 _bfd_elf_swap_verneed_out (output_bfd, &need,
3123 (Elf_External_Verneed *) p);
3124 p += sizeof (Elf_External_Verneed);
3125 for (i = 0; i < need.vn_cnt; ++i)
3127 _bfd_elf_swap_vernaux_in (output_bfd,
3128 (Elf_External_Vernaux *) p, &needaux);
3129 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3130 needaux.vna_name);
3131 _bfd_elf_swap_vernaux_out (output_bfd,
3132 &needaux,
3133 (Elf_External_Vernaux *) p);
3134 p += sizeof (Elf_External_Vernaux);
3137 while (need.vn_next);
3140 return TRUE;
3143 /* Add symbols from an ELF object file to the linker hash table. */
3145 static bfd_boolean
3146 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3148 Elf_Internal_Shdr *hdr;
3149 bfd_size_type symcount;
3150 bfd_size_type extsymcount;
3151 bfd_size_type extsymoff;
3152 struct elf_link_hash_entry **sym_hash;
3153 bfd_boolean dynamic;
3154 Elf_External_Versym *extversym = NULL;
3155 Elf_External_Versym *ever;
3156 struct elf_link_hash_entry *weaks;
3157 struct elf_link_hash_entry **nondeflt_vers = NULL;
3158 bfd_size_type nondeflt_vers_cnt = 0;
3159 Elf_Internal_Sym *isymbuf = NULL;
3160 Elf_Internal_Sym *isym;
3161 Elf_Internal_Sym *isymend;
3162 const struct elf_backend_data *bed;
3163 bfd_boolean add_needed;
3164 struct elf_link_hash_table *htab;
3165 bfd_size_type amt;
3166 void *alloc_mark = NULL;
3167 struct bfd_hash_entry **old_table = NULL;
3168 unsigned int old_size = 0;
3169 unsigned int old_count = 0;
3170 void *old_tab = NULL;
3171 void *old_hash;
3172 void *old_ent;
3173 struct bfd_link_hash_entry *old_undefs = NULL;
3174 struct bfd_link_hash_entry *old_undefs_tail = NULL;
3175 long old_dynsymcount = 0;
3176 size_t tabsize = 0;
3177 size_t hashsize = 0;
3179 htab = elf_hash_table (info);
3180 bed = get_elf_backend_data (abfd);
3182 if ((abfd->flags & DYNAMIC) == 0)
3183 dynamic = FALSE;
3184 else
3186 dynamic = TRUE;
3188 /* You can't use -r against a dynamic object. Also, there's no
3189 hope of using a dynamic object which does not exactly match
3190 the format of the output file. */
3191 if (info->relocatable
3192 || !is_elf_hash_table (htab)
3193 || htab->root.creator != abfd->xvec)
3195 if (info->relocatable)
3196 bfd_set_error (bfd_error_invalid_operation);
3197 else
3198 bfd_set_error (bfd_error_wrong_format);
3199 goto error_return;
3203 /* As a GNU extension, any input sections which are named
3204 .gnu.warning.SYMBOL are treated as warning symbols for the given
3205 symbol. This differs from .gnu.warning sections, which generate
3206 warnings when they are included in an output file. */
3207 if (info->executable)
3209 asection *s;
3211 for (s = abfd->sections; s != NULL; s = s->next)
3213 const char *name;
3215 name = bfd_get_section_name (abfd, s);
3216 if (CONST_STRNEQ (name, ".gnu.warning."))
3218 char *msg;
3219 bfd_size_type sz;
3221 name += sizeof ".gnu.warning." - 1;
3223 /* If this is a shared object, then look up the symbol
3224 in the hash table. If it is there, and it is already
3225 been defined, then we will not be using the entry
3226 from this shared object, so we don't need to warn.
3227 FIXME: If we see the definition in a regular object
3228 later on, we will warn, but we shouldn't. The only
3229 fix is to keep track of what warnings we are supposed
3230 to emit, and then handle them all at the end of the
3231 link. */
3232 if (dynamic)
3234 struct elf_link_hash_entry *h;
3236 h = elf_link_hash_lookup (htab, name, FALSE, FALSE, TRUE);
3238 /* FIXME: What about bfd_link_hash_common? */
3239 if (h != NULL
3240 && (h->root.type == bfd_link_hash_defined
3241 || h->root.type == bfd_link_hash_defweak))
3243 /* We don't want to issue this warning. Clobber
3244 the section size so that the warning does not
3245 get copied into the output file. */
3246 s->size = 0;
3247 continue;
3251 sz = s->size;
3252 msg = bfd_alloc (abfd, sz + 1);
3253 if (msg == NULL)
3254 goto error_return;
3256 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3257 goto error_return;
3259 msg[sz] = '\0';
3261 if (! (_bfd_generic_link_add_one_symbol
3262 (info, abfd, name, BSF_WARNING, s, 0, msg,
3263 FALSE, bed->collect, NULL)))
3264 goto error_return;
3266 if (! info->relocatable)
3268 /* Clobber the section size so that the warning does
3269 not get copied into the output file. */
3270 s->size = 0;
3272 /* Also set SEC_EXCLUDE, so that symbols defined in
3273 the warning section don't get copied to the output. */
3274 s->flags |= SEC_EXCLUDE;
3280 add_needed = TRUE;
3281 if (! dynamic)
3283 /* If we are creating a shared library, create all the dynamic
3284 sections immediately. We need to attach them to something,
3285 so we attach them to this BFD, provided it is the right
3286 format. FIXME: If there are no input BFD's of the same
3287 format as the output, we can't make a shared library. */
3288 if (info->shared
3289 && is_elf_hash_table (htab)
3290 && htab->root.creator == abfd->xvec
3291 && !htab->dynamic_sections_created)
3293 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3294 goto error_return;
3297 else if (!is_elf_hash_table (htab))
3298 goto error_return;
3299 else
3301 asection *s;
3302 const char *soname = NULL;
3303 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3304 int ret;
3306 /* ld --just-symbols and dynamic objects don't mix very well.
3307 ld shouldn't allow it. */
3308 if ((s = abfd->sections) != NULL
3309 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3310 abort ();
3312 /* If this dynamic lib was specified on the command line with
3313 --as-needed in effect, then we don't want to add a DT_NEEDED
3314 tag unless the lib is actually used. Similary for libs brought
3315 in by another lib's DT_NEEDED. When --no-add-needed is used
3316 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3317 any dynamic library in DT_NEEDED tags in the dynamic lib at
3318 all. */
3319 add_needed = (elf_dyn_lib_class (abfd)
3320 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3321 | DYN_NO_NEEDED)) == 0;
3323 s = bfd_get_section_by_name (abfd, ".dynamic");
3324 if (s != NULL)
3326 bfd_byte *dynbuf;
3327 bfd_byte *extdyn;
3328 int elfsec;
3329 unsigned long shlink;
3331 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3332 goto error_free_dyn;
3334 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3335 if (elfsec == -1)
3336 goto error_free_dyn;
3337 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3339 for (extdyn = dynbuf;
3340 extdyn < dynbuf + s->size;
3341 extdyn += bed->s->sizeof_dyn)
3343 Elf_Internal_Dyn dyn;
3345 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3346 if (dyn.d_tag == DT_SONAME)
3348 unsigned int tagv = dyn.d_un.d_val;
3349 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3350 if (soname == NULL)
3351 goto error_free_dyn;
3353 if (dyn.d_tag == DT_NEEDED)
3355 struct bfd_link_needed_list *n, **pn;
3356 char *fnm, *anm;
3357 unsigned int tagv = dyn.d_un.d_val;
3359 amt = sizeof (struct bfd_link_needed_list);
3360 n = bfd_alloc (abfd, amt);
3361 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3362 if (n == NULL || fnm == NULL)
3363 goto error_free_dyn;
3364 amt = strlen (fnm) + 1;
3365 anm = bfd_alloc (abfd, amt);
3366 if (anm == NULL)
3367 goto error_free_dyn;
3368 memcpy (anm, fnm, amt);
3369 n->name = anm;
3370 n->by = abfd;
3371 n->next = NULL;
3372 for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
3374 *pn = n;
3376 if (dyn.d_tag == DT_RUNPATH)
3378 struct bfd_link_needed_list *n, **pn;
3379 char *fnm, *anm;
3380 unsigned int tagv = dyn.d_un.d_val;
3382 amt = sizeof (struct bfd_link_needed_list);
3383 n = bfd_alloc (abfd, amt);
3384 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3385 if (n == NULL || fnm == NULL)
3386 goto error_free_dyn;
3387 amt = strlen (fnm) + 1;
3388 anm = bfd_alloc (abfd, amt);
3389 if (anm == NULL)
3390 goto error_free_dyn;
3391 memcpy (anm, fnm, amt);
3392 n->name = anm;
3393 n->by = abfd;
3394 n->next = NULL;
3395 for (pn = & runpath;
3396 *pn != NULL;
3397 pn = &(*pn)->next)
3399 *pn = n;
3401 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3402 if (!runpath && dyn.d_tag == DT_RPATH)
3404 struct bfd_link_needed_list *n, **pn;
3405 char *fnm, *anm;
3406 unsigned int tagv = dyn.d_un.d_val;
3408 amt = sizeof (struct bfd_link_needed_list);
3409 n = bfd_alloc (abfd, amt);
3410 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3411 if (n == NULL || fnm == NULL)
3412 goto error_free_dyn;
3413 amt = strlen (fnm) + 1;
3414 anm = bfd_alloc (abfd, amt);
3415 if (anm == NULL)
3417 error_free_dyn:
3418 free (dynbuf);
3419 goto error_return;
3421 memcpy (anm, fnm, amt);
3422 n->name = anm;
3423 n->by = abfd;
3424 n->next = NULL;
3425 for (pn = & rpath;
3426 *pn != NULL;
3427 pn = &(*pn)->next)
3429 *pn = n;
3433 free (dynbuf);
3436 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3437 frees all more recently bfd_alloc'd blocks as well. */
3438 if (runpath)
3439 rpath = runpath;
3441 if (rpath)
3443 struct bfd_link_needed_list **pn;
3444 for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
3446 *pn = rpath;
3449 /* We do not want to include any of the sections in a dynamic
3450 object in the output file. We hack by simply clobbering the
3451 list of sections in the BFD. This could be handled more
3452 cleanly by, say, a new section flag; the existing
3453 SEC_NEVER_LOAD flag is not the one we want, because that one
3454 still implies that the section takes up space in the output
3455 file. */
3456 bfd_section_list_clear (abfd);
3458 /* Find the name to use in a DT_NEEDED entry that refers to this
3459 object. If the object has a DT_SONAME entry, we use it.
3460 Otherwise, if the generic linker stuck something in
3461 elf_dt_name, we use that. Otherwise, we just use the file
3462 name. */
3463 if (soname == NULL || *soname == '\0')
3465 soname = elf_dt_name (abfd);
3466 if (soname == NULL || *soname == '\0')
3467 soname = bfd_get_filename (abfd);
3470 /* Save the SONAME because sometimes the linker emulation code
3471 will need to know it. */
3472 elf_dt_name (abfd) = soname;
3474 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3475 if (ret < 0)
3476 goto error_return;
3478 /* If we have already included this dynamic object in the
3479 link, just ignore it. There is no reason to include a
3480 particular dynamic object more than once. */
3481 if (ret > 0)
3482 return TRUE;
3485 /* If this is a dynamic object, we always link against the .dynsym
3486 symbol table, not the .symtab symbol table. The dynamic linker
3487 will only see the .dynsym symbol table, so there is no reason to
3488 look at .symtab for a dynamic object. */
3490 if (! dynamic || elf_dynsymtab (abfd) == 0)
3491 hdr = &elf_tdata (abfd)->symtab_hdr;
3492 else
3493 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3495 symcount = hdr->sh_size / bed->s->sizeof_sym;
3497 /* The sh_info field of the symtab header tells us where the
3498 external symbols start. We don't care about the local symbols at
3499 this point. */
3500 if (elf_bad_symtab (abfd))
3502 extsymcount = symcount;
3503 extsymoff = 0;
3505 else
3507 extsymcount = symcount - hdr->sh_info;
3508 extsymoff = hdr->sh_info;
3511 sym_hash = NULL;
3512 if (extsymcount != 0)
3514 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3515 NULL, NULL, NULL);
3516 if (isymbuf == NULL)
3517 goto error_return;
3519 /* We store a pointer to the hash table entry for each external
3520 symbol. */
3521 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3522 sym_hash = bfd_alloc (abfd, amt);
3523 if (sym_hash == NULL)
3524 goto error_free_sym;
3525 elf_sym_hashes (abfd) = sym_hash;
3528 if (dynamic)
3530 /* Read in any version definitions. */
3531 if (!_bfd_elf_slurp_version_tables (abfd,
3532 info->default_imported_symver))
3533 goto error_free_sym;
3535 /* Read in the symbol versions, but don't bother to convert them
3536 to internal format. */
3537 if (elf_dynversym (abfd) != 0)
3539 Elf_Internal_Shdr *versymhdr;
3541 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3542 extversym = bfd_malloc (versymhdr->sh_size);
3543 if (extversym == NULL)
3544 goto error_free_sym;
3545 amt = versymhdr->sh_size;
3546 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3547 || bfd_bread (extversym, amt, abfd) != amt)
3548 goto error_free_vers;
3552 /* If we are loading an as-needed shared lib, save the symbol table
3553 state before we start adding symbols. If the lib turns out
3554 to be unneeded, restore the state. */
3555 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
3557 unsigned int i;
3558 size_t entsize;
3560 for (entsize = 0, i = 0; i < htab->root.table.size; i++)
3562 struct bfd_hash_entry *p;
3563 struct elf_link_hash_entry *h;
3565 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3567 h = (struct elf_link_hash_entry *) p;
3568 entsize += htab->root.table.entsize;
3569 if (h->root.type == bfd_link_hash_warning)
3570 entsize += htab->root.table.entsize;
3574 tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
3575 hashsize = extsymcount * sizeof (struct elf_link_hash_entry *);
3576 old_tab = bfd_malloc (tabsize + entsize + hashsize);
3577 if (old_tab == NULL)
3578 goto error_free_vers;
3580 /* Remember the current objalloc pointer, so that all mem for
3581 symbols added can later be reclaimed. */
3582 alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
3583 if (alloc_mark == NULL)
3584 goto error_free_vers;
3586 /* Make a special call to the linker "notice" function to
3587 tell it that we are about to handle an as-needed lib. */
3588 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
3589 notice_as_needed))
3590 return FALSE;
3593 /* Clone the symbol table and sym hashes. Remember some
3594 pointers into the symbol table, and dynamic symbol count. */
3595 old_hash = (char *) old_tab + tabsize;
3596 old_ent = (char *) old_hash + hashsize;
3597 memcpy (old_tab, htab->root.table.table, tabsize);
3598 memcpy (old_hash, sym_hash, hashsize);
3599 old_undefs = htab->root.undefs;
3600 old_undefs_tail = htab->root.undefs_tail;
3601 old_table = htab->root.table.table;
3602 old_size = htab->root.table.size;
3603 old_count = htab->root.table.count;
3604 old_dynsymcount = htab->dynsymcount;
3606 for (i = 0; i < htab->root.table.size; i++)
3608 struct bfd_hash_entry *p;
3609 struct elf_link_hash_entry *h;
3611 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3613 memcpy (old_ent, p, htab->root.table.entsize);
3614 old_ent = (char *) old_ent + htab->root.table.entsize;
3615 h = (struct elf_link_hash_entry *) p;
3616 if (h->root.type == bfd_link_hash_warning)
3618 memcpy (old_ent, h->root.u.i.link, htab->root.table.entsize);
3619 old_ent = (char *) old_ent + htab->root.table.entsize;
3625 weaks = NULL;
3626 ever = extversym != NULL ? extversym + extsymoff : NULL;
3627 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3628 isym < isymend;
3629 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3631 int bind;
3632 bfd_vma value;
3633 asection *sec, *new_sec;
3634 flagword flags;
3635 const char *name;
3636 struct elf_link_hash_entry *h;
3637 bfd_boolean definition;
3638 bfd_boolean size_change_ok;
3639 bfd_boolean type_change_ok;
3640 bfd_boolean new_weakdef;
3641 bfd_boolean override;
3642 bfd_boolean common;
3643 unsigned int old_alignment;
3644 bfd *old_bfd;
3646 override = FALSE;
3648 flags = BSF_NO_FLAGS;
3649 sec = NULL;
3650 value = isym->st_value;
3651 *sym_hash = NULL;
3652 common = bed->common_definition (isym);
3654 bind = ELF_ST_BIND (isym->st_info);
3655 if (bind == STB_LOCAL)
3657 /* This should be impossible, since ELF requires that all
3658 global symbols follow all local symbols, and that sh_info
3659 point to the first global symbol. Unfortunately, Irix 5
3660 screws this up. */
3661 continue;
3663 else if (bind == STB_GLOBAL)
3665 if (isym->st_shndx != SHN_UNDEF && !common)
3666 flags = BSF_GLOBAL;
3668 else if (bind == STB_WEAK)
3669 flags = BSF_WEAK;
3670 else
3672 /* Leave it up to the processor backend. */
3675 if (isym->st_shndx == SHN_UNDEF)
3676 sec = bfd_und_section_ptr;
3677 else if (isym->st_shndx < SHN_LORESERVE
3678 || isym->st_shndx > SHN_HIRESERVE)
3680 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3681 if (sec == NULL)
3682 sec = bfd_abs_section_ptr;
3683 else if (sec->kept_section)
3685 /* Symbols from discarded section are undefined. We keep
3686 its visibility. */
3687 sec = bfd_und_section_ptr;
3688 isym->st_shndx = SHN_UNDEF;
3690 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3691 value -= sec->vma;
3693 else if (isym->st_shndx == SHN_ABS)
3694 sec = bfd_abs_section_ptr;
3695 else if (isym->st_shndx == SHN_COMMON)
3697 sec = bfd_com_section_ptr;
3698 /* What ELF calls the size we call the value. What ELF
3699 calls the value we call the alignment. */
3700 value = isym->st_size;
3702 else
3704 /* Leave it up to the processor backend. */
3707 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3708 isym->st_name);
3709 if (name == NULL)
3710 goto error_free_vers;
3712 if (isym->st_shndx == SHN_COMMON
3713 && ELF_ST_TYPE (isym->st_info) == STT_TLS
3714 && !info->relocatable)
3716 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3718 if (tcomm == NULL)
3720 tcomm = bfd_make_section_with_flags (abfd, ".tcommon",
3721 (SEC_ALLOC
3722 | SEC_IS_COMMON
3723 | SEC_LINKER_CREATED
3724 | SEC_THREAD_LOCAL));
3725 if (tcomm == NULL)
3726 goto error_free_vers;
3728 sec = tcomm;
3730 else if (bed->elf_add_symbol_hook)
3732 if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
3733 &sec, &value))
3734 goto error_free_vers;
3736 /* The hook function sets the name to NULL if this symbol
3737 should be skipped for some reason. */
3738 if (name == NULL)
3739 continue;
3742 /* Sanity check that all possibilities were handled. */
3743 if (sec == NULL)
3745 bfd_set_error (bfd_error_bad_value);
3746 goto error_free_vers;
3749 if (bfd_is_und_section (sec)
3750 || bfd_is_com_section (sec))
3751 definition = FALSE;
3752 else
3753 definition = TRUE;
3755 size_change_ok = FALSE;
3756 type_change_ok = bed->type_change_ok;
3757 old_alignment = 0;
3758 old_bfd = NULL;
3759 new_sec = sec;
3761 if (is_elf_hash_table (htab))
3763 Elf_Internal_Versym iver;
3764 unsigned int vernum = 0;
3765 bfd_boolean skip;
3767 if (ever == NULL)
3769 if (info->default_imported_symver)
3770 /* Use the default symbol version created earlier. */
3771 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3772 else
3773 iver.vs_vers = 0;
3775 else
3776 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3778 vernum = iver.vs_vers & VERSYM_VERSION;
3780 /* If this is a hidden symbol, or if it is not version
3781 1, we append the version name to the symbol name.
3782 However, we do not modify a non-hidden absolute symbol
3783 if it is not a function, because it might be the version
3784 symbol itself. FIXME: What if it isn't? */
3785 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3786 || (vernum > 1 && (! bfd_is_abs_section (sec)
3787 || ELF_ST_TYPE (isym->st_info) == STT_FUNC)))
3789 const char *verstr;
3790 size_t namelen, verlen, newlen;
3791 char *newname, *p;
3793 if (isym->st_shndx != SHN_UNDEF)
3795 if (vernum > elf_tdata (abfd)->cverdefs)
3796 verstr = NULL;
3797 else if (vernum > 1)
3798 verstr =
3799 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3800 else
3801 verstr = "";
3803 if (verstr == NULL)
3805 (*_bfd_error_handler)
3806 (_("%B: %s: invalid version %u (max %d)"),
3807 abfd, name, vernum,
3808 elf_tdata (abfd)->cverdefs);
3809 bfd_set_error (bfd_error_bad_value);
3810 goto error_free_vers;
3813 else
3815 /* We cannot simply test for the number of
3816 entries in the VERNEED section since the
3817 numbers for the needed versions do not start
3818 at 0. */
3819 Elf_Internal_Verneed *t;
3821 verstr = NULL;
3822 for (t = elf_tdata (abfd)->verref;
3823 t != NULL;
3824 t = t->vn_nextref)
3826 Elf_Internal_Vernaux *a;
3828 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3830 if (a->vna_other == vernum)
3832 verstr = a->vna_nodename;
3833 break;
3836 if (a != NULL)
3837 break;
3839 if (verstr == NULL)
3841 (*_bfd_error_handler)
3842 (_("%B: %s: invalid needed version %d"),
3843 abfd, name, vernum);
3844 bfd_set_error (bfd_error_bad_value);
3845 goto error_free_vers;
3849 namelen = strlen (name);
3850 verlen = strlen (verstr);
3851 newlen = namelen + verlen + 2;
3852 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3853 && isym->st_shndx != SHN_UNDEF)
3854 ++newlen;
3856 newname = bfd_hash_allocate (&htab->root.table, newlen);
3857 if (newname == NULL)
3858 goto error_free_vers;
3859 memcpy (newname, name, namelen);
3860 p = newname + namelen;
3861 *p++ = ELF_VER_CHR;
3862 /* If this is a defined non-hidden version symbol,
3863 we add another @ to the name. This indicates the
3864 default version of the symbol. */
3865 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3866 && isym->st_shndx != SHN_UNDEF)
3867 *p++ = ELF_VER_CHR;
3868 memcpy (p, verstr, verlen + 1);
3870 name = newname;
3873 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
3874 &value, &old_alignment,
3875 sym_hash, &skip, &override,
3876 &type_change_ok, &size_change_ok))
3877 goto error_free_vers;
3879 if (skip)
3880 continue;
3882 if (override)
3883 definition = FALSE;
3885 h = *sym_hash;
3886 while (h->root.type == bfd_link_hash_indirect
3887 || h->root.type == bfd_link_hash_warning)
3888 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3890 /* Remember the old alignment if this is a common symbol, so
3891 that we don't reduce the alignment later on. We can't
3892 check later, because _bfd_generic_link_add_one_symbol
3893 will set a default for the alignment which we want to
3894 override. We also remember the old bfd where the existing
3895 definition comes from. */
3896 switch (h->root.type)
3898 default:
3899 break;
3901 case bfd_link_hash_defined:
3902 case bfd_link_hash_defweak:
3903 old_bfd = h->root.u.def.section->owner;
3904 break;
3906 case bfd_link_hash_common:
3907 old_bfd = h->root.u.c.p->section->owner;
3908 old_alignment = h->root.u.c.p->alignment_power;
3909 break;
3912 if (elf_tdata (abfd)->verdef != NULL
3913 && ! override
3914 && vernum > 1
3915 && definition)
3916 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3919 if (! (_bfd_generic_link_add_one_symbol
3920 (info, abfd, name, flags, sec, value, NULL, FALSE, bed->collect,
3921 (struct bfd_link_hash_entry **) sym_hash)))
3922 goto error_free_vers;
3924 h = *sym_hash;
3925 while (h->root.type == bfd_link_hash_indirect
3926 || h->root.type == bfd_link_hash_warning)
3927 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3928 *sym_hash = h;
3930 new_weakdef = FALSE;
3931 if (dynamic
3932 && definition
3933 && (flags & BSF_WEAK) != 0
3934 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3935 && is_elf_hash_table (htab)
3936 && h->u.weakdef == NULL)
3938 /* Keep a list of all weak defined non function symbols from
3939 a dynamic object, using the weakdef field. Later in this
3940 function we will set the weakdef field to the correct
3941 value. We only put non-function symbols from dynamic
3942 objects on this list, because that happens to be the only
3943 time we need to know the normal symbol corresponding to a
3944 weak symbol, and the information is time consuming to
3945 figure out. If the weakdef field is not already NULL,
3946 then this symbol was already defined by some previous
3947 dynamic object, and we will be using that previous
3948 definition anyhow. */
3950 h->u.weakdef = weaks;
3951 weaks = h;
3952 new_weakdef = TRUE;
3955 /* Set the alignment of a common symbol. */
3956 if ((common || bfd_is_com_section (sec))
3957 && h->root.type == bfd_link_hash_common)
3959 unsigned int align;
3961 if (common)
3962 align = bfd_log2 (isym->st_value);
3963 else
3965 /* The new symbol is a common symbol in a shared object.
3966 We need to get the alignment from the section. */
3967 align = new_sec->alignment_power;
3969 if (align > old_alignment
3970 /* Permit an alignment power of zero if an alignment of one
3971 is specified and no other alignments have been specified. */
3972 || (isym->st_value == 1 && old_alignment == 0))
3973 h->root.u.c.p->alignment_power = align;
3974 else
3975 h->root.u.c.p->alignment_power = old_alignment;
3978 if (is_elf_hash_table (htab))
3980 bfd_boolean dynsym;
3982 /* Check the alignment when a common symbol is involved. This
3983 can change when a common symbol is overridden by a normal
3984 definition or a common symbol is ignored due to the old
3985 normal definition. We need to make sure the maximum
3986 alignment is maintained. */
3987 if ((old_alignment || common)
3988 && h->root.type != bfd_link_hash_common)
3990 unsigned int common_align;
3991 unsigned int normal_align;
3992 unsigned int symbol_align;
3993 bfd *normal_bfd;
3994 bfd *common_bfd;
3996 symbol_align = ffs (h->root.u.def.value) - 1;
3997 if (h->root.u.def.section->owner != NULL
3998 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
4000 normal_align = h->root.u.def.section->alignment_power;
4001 if (normal_align > symbol_align)
4002 normal_align = symbol_align;
4004 else
4005 normal_align = symbol_align;
4007 if (old_alignment)
4009 common_align = old_alignment;
4010 common_bfd = old_bfd;
4011 normal_bfd = abfd;
4013 else
4015 common_align = bfd_log2 (isym->st_value);
4016 common_bfd = abfd;
4017 normal_bfd = old_bfd;
4020 if (normal_align < common_align)
4022 /* PR binutils/2735 */
4023 if (normal_bfd == NULL)
4024 (*_bfd_error_handler)
4025 (_("Warning: alignment %u of common symbol `%s' in %B"
4026 " is greater than the alignment (%u) of its section %A"),
4027 common_bfd, h->root.u.def.section,
4028 1 << common_align, name, 1 << normal_align);
4029 else
4030 (*_bfd_error_handler)
4031 (_("Warning: alignment %u of symbol `%s' in %B"
4032 " is smaller than %u in %B"),
4033 normal_bfd, common_bfd,
4034 1 << normal_align, name, 1 << common_align);
4038 /* Remember the symbol size if it isn't undefined. */
4039 if ((isym->st_size != 0 && isym->st_shndx != SHN_UNDEF)
4040 && (definition || h->size == 0))
4042 if (h->size != 0
4043 && h->size != isym->st_size
4044 && ! size_change_ok)
4045 (*_bfd_error_handler)
4046 (_("Warning: size of symbol `%s' changed"
4047 " from %lu in %B to %lu in %B"),
4048 old_bfd, abfd,
4049 name, (unsigned long) h->size,
4050 (unsigned long) isym->st_size);
4052 h->size = isym->st_size;
4055 /* If this is a common symbol, then we always want H->SIZE
4056 to be the size of the common symbol. The code just above
4057 won't fix the size if a common symbol becomes larger. We
4058 don't warn about a size change here, because that is
4059 covered by --warn-common. */
4060 if (h->root.type == bfd_link_hash_common)
4061 h->size = h->root.u.c.size;
4063 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
4064 && (definition || h->type == STT_NOTYPE))
4066 if (h->type != STT_NOTYPE
4067 && h->type != ELF_ST_TYPE (isym->st_info)
4068 && ! type_change_ok)
4069 (*_bfd_error_handler)
4070 (_("Warning: type of symbol `%s' changed"
4071 " from %d to %d in %B"),
4072 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
4074 h->type = ELF_ST_TYPE (isym->st_info);
4077 /* If st_other has a processor-specific meaning, specific
4078 code might be needed here. We never merge the visibility
4079 attribute with the one from a dynamic object. */
4080 if (bed->elf_backend_merge_symbol_attribute)
4081 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
4082 dynamic);
4084 /* If this symbol has default visibility and the user has requested
4085 we not re-export it, then mark it as hidden. */
4086 if (definition && !dynamic
4087 && (abfd->no_export
4088 || (abfd->my_archive && abfd->my_archive->no_export))
4089 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
4090 isym->st_other = (STV_HIDDEN
4091 | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
4093 if (ELF_ST_VISIBILITY (isym->st_other) != 0 && !dynamic)
4095 unsigned char hvis, symvis, other, nvis;
4097 /* Only merge the visibility. Leave the remainder of the
4098 st_other field to elf_backend_merge_symbol_attribute. */
4099 other = h->other & ~ELF_ST_VISIBILITY (-1);
4101 /* Combine visibilities, using the most constraining one. */
4102 hvis = ELF_ST_VISIBILITY (h->other);
4103 symvis = ELF_ST_VISIBILITY (isym->st_other);
4104 if (! hvis)
4105 nvis = symvis;
4106 else if (! symvis)
4107 nvis = hvis;
4108 else
4109 nvis = hvis < symvis ? hvis : symvis;
4111 h->other = other | nvis;
4114 /* Set a flag in the hash table entry indicating the type of
4115 reference or definition we just found. Keep a count of
4116 the number of dynamic symbols we find. A dynamic symbol
4117 is one which is referenced or defined by both a regular
4118 object and a shared object. */
4119 dynsym = FALSE;
4120 if (! dynamic)
4122 if (! definition)
4124 h->ref_regular = 1;
4125 if (bind != STB_WEAK)
4126 h->ref_regular_nonweak = 1;
4128 else
4129 h->def_regular = 1;
4130 if (! info->executable
4131 || h->def_dynamic
4132 || h->ref_dynamic)
4133 dynsym = TRUE;
4135 else
4137 if (! definition)
4138 h->ref_dynamic = 1;
4139 else
4140 h->def_dynamic = 1;
4141 if (h->def_regular
4142 || h->ref_regular
4143 || (h->u.weakdef != NULL
4144 && ! new_weakdef
4145 && h->u.weakdef->dynindx != -1))
4146 dynsym = TRUE;
4149 if (definition && (sec->flags & SEC_DEBUGGING))
4151 /* We don't want to make debug symbol dynamic. */
4152 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4153 dynsym = FALSE;
4156 /* Check to see if we need to add an indirect symbol for
4157 the default name. */
4158 if (definition || h->root.type == bfd_link_hash_common)
4159 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4160 &sec, &value, &dynsym,
4161 override))
4162 goto error_free_vers;
4164 if (definition && !dynamic)
4166 char *p = strchr (name, ELF_VER_CHR);
4167 if (p != NULL && p[1] != ELF_VER_CHR)
4169 /* Queue non-default versions so that .symver x, x@FOO
4170 aliases can be checked. */
4171 if (!nondeflt_vers)
4173 amt = ((isymend - isym + 1)
4174 * sizeof (struct elf_link_hash_entry *));
4175 nondeflt_vers = bfd_malloc (amt);
4177 nondeflt_vers[nondeflt_vers_cnt++] = h;
4181 if (dynsym && h->dynindx == -1)
4183 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4184 goto error_free_vers;
4185 if (h->u.weakdef != NULL
4186 && ! new_weakdef
4187 && h->u.weakdef->dynindx == -1)
4189 if (!bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4190 goto error_free_vers;
4193 else if (dynsym && h->dynindx != -1)
4194 /* If the symbol already has a dynamic index, but
4195 visibility says it should not be visible, turn it into
4196 a local symbol. */
4197 switch (ELF_ST_VISIBILITY (h->other))
4199 case STV_INTERNAL:
4200 case STV_HIDDEN:
4201 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4202 dynsym = FALSE;
4203 break;
4206 if (!add_needed
4207 && definition
4208 && dynsym
4209 && h->ref_regular)
4211 int ret;
4212 const char *soname = elf_dt_name (abfd);
4214 /* A symbol from a library loaded via DT_NEEDED of some
4215 other library is referenced by a regular object.
4216 Add a DT_NEEDED entry for it. Issue an error if
4217 --no-add-needed is used. */
4218 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4220 (*_bfd_error_handler)
4221 (_("%s: invalid DSO for symbol `%s' definition"),
4222 abfd, name);
4223 bfd_set_error (bfd_error_bad_value);
4224 goto error_free_vers;
4227 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4229 add_needed = TRUE;
4230 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4231 if (ret < 0)
4232 goto error_free_vers;
4234 BFD_ASSERT (ret == 0);
4239 if (extversym != NULL)
4241 free (extversym);
4242 extversym = NULL;
4245 if (isymbuf != NULL)
4247 free (isymbuf);
4248 isymbuf = NULL;
4251 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4253 unsigned int i;
4255 /* Restore the symbol table. */
4256 if (bed->as_needed_cleanup)
4257 (*bed->as_needed_cleanup) (abfd, info);
4258 old_hash = (char *) old_tab + tabsize;
4259 old_ent = (char *) old_hash + hashsize;
4260 sym_hash = elf_sym_hashes (abfd);
4261 htab->root.table.table = old_table;
4262 htab->root.table.size = old_size;
4263 htab->root.table.count = old_count;
4264 memcpy (htab->root.table.table, old_tab, tabsize);
4265 memcpy (sym_hash, old_hash, hashsize);
4266 htab->root.undefs = old_undefs;
4267 htab->root.undefs_tail = old_undefs_tail;
4268 for (i = 0; i < htab->root.table.size; i++)
4270 struct bfd_hash_entry *p;
4271 struct elf_link_hash_entry *h;
4273 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4275 h = (struct elf_link_hash_entry *) p;
4276 if (h->root.type == bfd_link_hash_warning)
4277 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4278 if (h->dynindx >= old_dynsymcount)
4279 _bfd_elf_strtab_delref (htab->dynstr, h->dynstr_index);
4281 memcpy (p, old_ent, htab->root.table.entsize);
4282 old_ent = (char *) old_ent + htab->root.table.entsize;
4283 h = (struct elf_link_hash_entry *) p;
4284 if (h->root.type == bfd_link_hash_warning)
4286 memcpy (h->root.u.i.link, old_ent, htab->root.table.entsize);
4287 old_ent = (char *) old_ent + htab->root.table.entsize;
4292 /* Make a special call to the linker "notice" function to
4293 tell it that symbols added for crefs may need to be removed. */
4294 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4295 notice_not_needed))
4296 return FALSE;
4298 free (old_tab);
4299 objalloc_free_block ((struct objalloc *) htab->root.table.memory,
4300 alloc_mark);
4301 if (nondeflt_vers != NULL)
4302 free (nondeflt_vers);
4303 return TRUE;
4306 if (old_tab != NULL)
4308 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4309 notice_needed))
4310 return FALSE;
4311 free (old_tab);
4312 old_tab = NULL;
4315 /* Now that all the symbols from this input file are created, handle
4316 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4317 if (nondeflt_vers != NULL)
4319 bfd_size_type cnt, symidx;
4321 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4323 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4324 char *shortname, *p;
4326 p = strchr (h->root.root.string, ELF_VER_CHR);
4327 if (p == NULL
4328 || (h->root.type != bfd_link_hash_defined
4329 && h->root.type != bfd_link_hash_defweak))
4330 continue;
4332 amt = p - h->root.root.string;
4333 shortname = bfd_malloc (amt + 1);
4334 memcpy (shortname, h->root.root.string, amt);
4335 shortname[amt] = '\0';
4337 hi = (struct elf_link_hash_entry *)
4338 bfd_link_hash_lookup (&htab->root, shortname,
4339 FALSE, FALSE, FALSE);
4340 if (hi != NULL
4341 && hi->root.type == h->root.type
4342 && hi->root.u.def.value == h->root.u.def.value
4343 && hi->root.u.def.section == h->root.u.def.section)
4345 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4346 hi->root.type = bfd_link_hash_indirect;
4347 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4348 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
4349 sym_hash = elf_sym_hashes (abfd);
4350 if (sym_hash)
4351 for (symidx = 0; symidx < extsymcount; ++symidx)
4352 if (sym_hash[symidx] == hi)
4354 sym_hash[symidx] = h;
4355 break;
4358 free (shortname);
4360 free (nondeflt_vers);
4361 nondeflt_vers = NULL;
4364 /* Now set the weakdefs field correctly for all the weak defined
4365 symbols we found. The only way to do this is to search all the
4366 symbols. Since we only need the information for non functions in
4367 dynamic objects, that's the only time we actually put anything on
4368 the list WEAKS. We need this information so that if a regular
4369 object refers to a symbol defined weakly in a dynamic object, the
4370 real symbol in the dynamic object is also put in the dynamic
4371 symbols; we also must arrange for both symbols to point to the
4372 same memory location. We could handle the general case of symbol
4373 aliasing, but a general symbol alias can only be generated in
4374 assembler code, handling it correctly would be very time
4375 consuming, and other ELF linkers don't handle general aliasing
4376 either. */
4377 if (weaks != NULL)
4379 struct elf_link_hash_entry **hpp;
4380 struct elf_link_hash_entry **hppend;
4381 struct elf_link_hash_entry **sorted_sym_hash;
4382 struct elf_link_hash_entry *h;
4383 size_t sym_count;
4385 /* Since we have to search the whole symbol list for each weak
4386 defined symbol, search time for N weak defined symbols will be
4387 O(N^2). Binary search will cut it down to O(NlogN). */
4388 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4389 sorted_sym_hash = bfd_malloc (amt);
4390 if (sorted_sym_hash == NULL)
4391 goto error_return;
4392 sym_hash = sorted_sym_hash;
4393 hpp = elf_sym_hashes (abfd);
4394 hppend = hpp + extsymcount;
4395 sym_count = 0;
4396 for (; hpp < hppend; hpp++)
4398 h = *hpp;
4399 if (h != NULL
4400 && h->root.type == bfd_link_hash_defined
4401 && h->type != STT_FUNC)
4403 *sym_hash = h;
4404 sym_hash++;
4405 sym_count++;
4409 qsort (sorted_sym_hash, sym_count,
4410 sizeof (struct elf_link_hash_entry *),
4411 elf_sort_symbol);
4413 while (weaks != NULL)
4415 struct elf_link_hash_entry *hlook;
4416 asection *slook;
4417 bfd_vma vlook;
4418 long ilook;
4419 size_t i, j, idx;
4421 hlook = weaks;
4422 weaks = hlook->u.weakdef;
4423 hlook->u.weakdef = NULL;
4425 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4426 || hlook->root.type == bfd_link_hash_defweak
4427 || hlook->root.type == bfd_link_hash_common
4428 || hlook->root.type == bfd_link_hash_indirect);
4429 slook = hlook->root.u.def.section;
4430 vlook = hlook->root.u.def.value;
4432 ilook = -1;
4433 i = 0;
4434 j = sym_count;
4435 while (i < j)
4437 bfd_signed_vma vdiff;
4438 idx = (i + j) / 2;
4439 h = sorted_sym_hash [idx];
4440 vdiff = vlook - h->root.u.def.value;
4441 if (vdiff < 0)
4442 j = idx;
4443 else if (vdiff > 0)
4444 i = idx + 1;
4445 else
4447 long sdiff = slook->id - h->root.u.def.section->id;
4448 if (sdiff < 0)
4449 j = idx;
4450 else if (sdiff > 0)
4451 i = idx + 1;
4452 else
4454 ilook = idx;
4455 break;
4460 /* We didn't find a value/section match. */
4461 if (ilook == -1)
4462 continue;
4464 for (i = ilook; i < sym_count; i++)
4466 h = sorted_sym_hash [i];
4468 /* Stop if value or section doesn't match. */
4469 if (h->root.u.def.value != vlook
4470 || h->root.u.def.section != slook)
4471 break;
4472 else if (h != hlook)
4474 hlook->u.weakdef = h;
4476 /* If the weak definition is in the list of dynamic
4477 symbols, make sure the real definition is put
4478 there as well. */
4479 if (hlook->dynindx != -1 && h->dynindx == -1)
4481 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4482 goto error_return;
4485 /* If the real definition is in the list of dynamic
4486 symbols, make sure the weak definition is put
4487 there as well. If we don't do this, then the
4488 dynamic loader might not merge the entries for the
4489 real definition and the weak definition. */
4490 if (h->dynindx != -1 && hlook->dynindx == -1)
4492 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4493 goto error_return;
4495 break;
4500 free (sorted_sym_hash);
4503 if (bed->check_directives)
4504 (*bed->check_directives) (abfd, info);
4506 /* If this object is the same format as the output object, and it is
4507 not a shared library, then let the backend look through the
4508 relocs.
4510 This is required to build global offset table entries and to
4511 arrange for dynamic relocs. It is not required for the
4512 particular common case of linking non PIC code, even when linking
4513 against shared libraries, but unfortunately there is no way of
4514 knowing whether an object file has been compiled PIC or not.
4515 Looking through the relocs is not particularly time consuming.
4516 The problem is that we must either (1) keep the relocs in memory,
4517 which causes the linker to require additional runtime memory or
4518 (2) read the relocs twice from the input file, which wastes time.
4519 This would be a good case for using mmap.
4521 I have no idea how to handle linking PIC code into a file of a
4522 different format. It probably can't be done. */
4523 if (! dynamic
4524 && is_elf_hash_table (htab)
4525 && htab->root.creator == abfd->xvec
4526 && bed->check_relocs != NULL)
4528 asection *o;
4530 for (o = abfd->sections; o != NULL; o = o->next)
4532 Elf_Internal_Rela *internal_relocs;
4533 bfd_boolean ok;
4535 if ((o->flags & SEC_RELOC) == 0
4536 || o->reloc_count == 0
4537 || ((info->strip == strip_all || info->strip == strip_debugger)
4538 && (o->flags & SEC_DEBUGGING) != 0)
4539 || bfd_is_abs_section (o->output_section))
4540 continue;
4542 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4543 info->keep_memory);
4544 if (internal_relocs == NULL)
4545 goto error_return;
4547 ok = (*bed->check_relocs) (abfd, info, o, internal_relocs);
4549 if (elf_section_data (o)->relocs != internal_relocs)
4550 free (internal_relocs);
4552 if (! ok)
4553 goto error_return;
4557 /* If this is a non-traditional link, try to optimize the handling
4558 of the .stab/.stabstr sections. */
4559 if (! dynamic
4560 && ! info->traditional_format
4561 && is_elf_hash_table (htab)
4562 && (info->strip != strip_all && info->strip != strip_debugger))
4564 asection *stabstr;
4566 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4567 if (stabstr != NULL)
4569 bfd_size_type string_offset = 0;
4570 asection *stab;
4572 for (stab = abfd->sections; stab; stab = stab->next)
4573 if (CONST_STRNEQ (stab->name, ".stab")
4574 && (!stab->name[5] ||
4575 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4576 && (stab->flags & SEC_MERGE) == 0
4577 && !bfd_is_abs_section (stab->output_section))
4579 struct bfd_elf_section_data *secdata;
4581 secdata = elf_section_data (stab);
4582 if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
4583 stabstr, &secdata->sec_info,
4584 &string_offset))
4585 goto error_return;
4586 if (secdata->sec_info)
4587 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4592 if (is_elf_hash_table (htab) && add_needed)
4594 /* Add this bfd to the loaded list. */
4595 struct elf_link_loaded_list *n;
4597 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4598 if (n == NULL)
4599 goto error_return;
4600 n->abfd = abfd;
4601 n->next = htab->loaded;
4602 htab->loaded = n;
4605 return TRUE;
4607 error_free_vers:
4608 if (old_tab != NULL)
4609 free (old_tab);
4610 if (nondeflt_vers != NULL)
4611 free (nondeflt_vers);
4612 if (extversym != NULL)
4613 free (extversym);
4614 error_free_sym:
4615 if (isymbuf != NULL)
4616 free (isymbuf);
4617 error_return:
4618 return FALSE;
4621 /* Return the linker hash table entry of a symbol that might be
4622 satisfied by an archive symbol. Return -1 on error. */
4624 struct elf_link_hash_entry *
4625 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4626 struct bfd_link_info *info,
4627 const char *name)
4629 struct elf_link_hash_entry *h;
4630 char *p, *copy;
4631 size_t len, first;
4633 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4634 if (h != NULL)
4635 return h;
4637 /* If this is a default version (the name contains @@), look up the
4638 symbol again with only one `@' as well as without the version.
4639 The effect is that references to the symbol with and without the
4640 version will be matched by the default symbol in the archive. */
4642 p = strchr (name, ELF_VER_CHR);
4643 if (p == NULL || p[1] != ELF_VER_CHR)
4644 return h;
4646 /* First check with only one `@'. */
4647 len = strlen (name);
4648 copy = bfd_alloc (abfd, len);
4649 if (copy == NULL)
4650 return (struct elf_link_hash_entry *) 0 - 1;
4652 first = p - name + 1;
4653 memcpy (copy, name, first);
4654 memcpy (copy + first, name + first + 1, len - first);
4656 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4657 if (h == NULL)
4659 /* We also need to check references to the symbol without the
4660 version. */
4661 copy[first - 1] = '\0';
4662 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4663 FALSE, FALSE, FALSE);
4666 bfd_release (abfd, copy);
4667 return h;
4670 /* Add symbols from an ELF archive file to the linker hash table. We
4671 don't use _bfd_generic_link_add_archive_symbols because of a
4672 problem which arises on UnixWare. The UnixWare libc.so is an
4673 archive which includes an entry libc.so.1 which defines a bunch of
4674 symbols. The libc.so archive also includes a number of other
4675 object files, which also define symbols, some of which are the same
4676 as those defined in libc.so.1. Correct linking requires that we
4677 consider each object file in turn, and include it if it defines any
4678 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4679 this; it looks through the list of undefined symbols, and includes
4680 any object file which defines them. When this algorithm is used on
4681 UnixWare, it winds up pulling in libc.so.1 early and defining a
4682 bunch of symbols. This means that some of the other objects in the
4683 archive are not included in the link, which is incorrect since they
4684 precede libc.so.1 in the archive.
4686 Fortunately, ELF archive handling is simpler than that done by
4687 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4688 oddities. In ELF, if we find a symbol in the archive map, and the
4689 symbol is currently undefined, we know that we must pull in that
4690 object file.
4692 Unfortunately, we do have to make multiple passes over the symbol
4693 table until nothing further is resolved. */
4695 static bfd_boolean
4696 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4698 symindex c;
4699 bfd_boolean *defined = NULL;
4700 bfd_boolean *included = NULL;
4701 carsym *symdefs;
4702 bfd_boolean loop;
4703 bfd_size_type amt;
4704 const struct elf_backend_data *bed;
4705 struct elf_link_hash_entry * (*archive_symbol_lookup)
4706 (bfd *, struct bfd_link_info *, const char *);
4708 if (! bfd_has_map (abfd))
4710 /* An empty archive is a special case. */
4711 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4712 return TRUE;
4713 bfd_set_error (bfd_error_no_armap);
4714 return FALSE;
4717 /* Keep track of all symbols we know to be already defined, and all
4718 files we know to be already included. This is to speed up the
4719 second and subsequent passes. */
4720 c = bfd_ardata (abfd)->symdef_count;
4721 if (c == 0)
4722 return TRUE;
4723 amt = c;
4724 amt *= sizeof (bfd_boolean);
4725 defined = bfd_zmalloc (amt);
4726 included = bfd_zmalloc (amt);
4727 if (defined == NULL || included == NULL)
4728 goto error_return;
4730 symdefs = bfd_ardata (abfd)->symdefs;
4731 bed = get_elf_backend_data (abfd);
4732 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4736 file_ptr last;
4737 symindex i;
4738 carsym *symdef;
4739 carsym *symdefend;
4741 loop = FALSE;
4742 last = -1;
4744 symdef = symdefs;
4745 symdefend = symdef + c;
4746 for (i = 0; symdef < symdefend; symdef++, i++)
4748 struct elf_link_hash_entry *h;
4749 bfd *element;
4750 struct bfd_link_hash_entry *undefs_tail;
4751 symindex mark;
4753 if (defined[i] || included[i])
4754 continue;
4755 if (symdef->file_offset == last)
4757 included[i] = TRUE;
4758 continue;
4761 h = archive_symbol_lookup (abfd, info, symdef->name);
4762 if (h == (struct elf_link_hash_entry *) 0 - 1)
4763 goto error_return;
4765 if (h == NULL)
4766 continue;
4768 if (h->root.type == bfd_link_hash_common)
4770 /* We currently have a common symbol. The archive map contains
4771 a reference to this symbol, so we may want to include it. We
4772 only want to include it however, if this archive element
4773 contains a definition of the symbol, not just another common
4774 declaration of it.
4776 Unfortunately some archivers (including GNU ar) will put
4777 declarations of common symbols into their archive maps, as
4778 well as real definitions, so we cannot just go by the archive
4779 map alone. Instead we must read in the element's symbol
4780 table and check that to see what kind of symbol definition
4781 this is. */
4782 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4783 continue;
4785 else if (h->root.type != bfd_link_hash_undefined)
4787 if (h->root.type != bfd_link_hash_undefweak)
4788 defined[i] = TRUE;
4789 continue;
4792 /* We need to include this archive member. */
4793 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4794 if (element == NULL)
4795 goto error_return;
4797 if (! bfd_check_format (element, bfd_object))
4798 goto error_return;
4800 /* Doublecheck that we have not included this object
4801 already--it should be impossible, but there may be
4802 something wrong with the archive. */
4803 if (element->archive_pass != 0)
4805 bfd_set_error (bfd_error_bad_value);
4806 goto error_return;
4808 element->archive_pass = 1;
4810 undefs_tail = info->hash->undefs_tail;
4812 if (! (*info->callbacks->add_archive_element) (info, element,
4813 symdef->name))
4814 goto error_return;
4815 if (! bfd_link_add_symbols (element, info))
4816 goto error_return;
4818 /* If there are any new undefined symbols, we need to make
4819 another pass through the archive in order to see whether
4820 they can be defined. FIXME: This isn't perfect, because
4821 common symbols wind up on undefs_tail and because an
4822 undefined symbol which is defined later on in this pass
4823 does not require another pass. This isn't a bug, but it
4824 does make the code less efficient than it could be. */
4825 if (undefs_tail != info->hash->undefs_tail)
4826 loop = TRUE;
4828 /* Look backward to mark all symbols from this object file
4829 which we have already seen in this pass. */
4830 mark = i;
4833 included[mark] = TRUE;
4834 if (mark == 0)
4835 break;
4836 --mark;
4838 while (symdefs[mark].file_offset == symdef->file_offset);
4840 /* We mark subsequent symbols from this object file as we go
4841 on through the loop. */
4842 last = symdef->file_offset;
4845 while (loop);
4847 free (defined);
4848 free (included);
4850 return TRUE;
4852 error_return:
4853 if (defined != NULL)
4854 free (defined);
4855 if (included != NULL)
4856 free (included);
4857 return FALSE;
4860 /* Given an ELF BFD, add symbols to the global hash table as
4861 appropriate. */
4863 bfd_boolean
4864 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4866 switch (bfd_get_format (abfd))
4868 case bfd_object:
4869 return elf_link_add_object_symbols (abfd, info);
4870 case bfd_archive:
4871 return elf_link_add_archive_symbols (abfd, info);
4872 default:
4873 bfd_set_error (bfd_error_wrong_format);
4874 return FALSE;
4878 /* This function will be called though elf_link_hash_traverse to store
4879 all hash value of the exported symbols in an array. */
4881 static bfd_boolean
4882 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4884 unsigned long **valuep = data;
4885 const char *name;
4886 char *p;
4887 unsigned long ha;
4888 char *alc = NULL;
4890 if (h->root.type == bfd_link_hash_warning)
4891 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4893 /* Ignore indirect symbols. These are added by the versioning code. */
4894 if (h->dynindx == -1)
4895 return TRUE;
4897 name = h->root.root.string;
4898 p = strchr (name, ELF_VER_CHR);
4899 if (p != NULL)
4901 alc = bfd_malloc (p - name + 1);
4902 memcpy (alc, name, p - name);
4903 alc[p - name] = '\0';
4904 name = alc;
4907 /* Compute the hash value. */
4908 ha = bfd_elf_hash (name);
4910 /* Store the found hash value in the array given as the argument. */
4911 *(*valuep)++ = ha;
4913 /* And store it in the struct so that we can put it in the hash table
4914 later. */
4915 h->u.elf_hash_value = ha;
4917 if (alc != NULL)
4918 free (alc);
4920 return TRUE;
4923 struct collect_gnu_hash_codes
4925 bfd *output_bfd;
4926 const struct elf_backend_data *bed;
4927 unsigned long int nsyms;
4928 unsigned long int maskbits;
4929 unsigned long int *hashcodes;
4930 unsigned long int *hashval;
4931 unsigned long int *indx;
4932 unsigned long int *counts;
4933 bfd_vma *bitmask;
4934 bfd_byte *contents;
4935 long int min_dynindx;
4936 unsigned long int bucketcount;
4937 unsigned long int symindx;
4938 long int local_indx;
4939 long int shift1, shift2;
4940 unsigned long int mask;
4943 /* This function will be called though elf_link_hash_traverse to store
4944 all hash value of the exported symbols in an array. */
4946 static bfd_boolean
4947 elf_collect_gnu_hash_codes (struct elf_link_hash_entry *h, void *data)
4949 struct collect_gnu_hash_codes *s = data;
4950 const char *name;
4951 char *p;
4952 unsigned long ha;
4953 char *alc = NULL;
4955 if (h->root.type == bfd_link_hash_warning)
4956 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4958 /* Ignore indirect symbols. These are added by the versioning code. */
4959 if (h->dynindx == -1)
4960 return TRUE;
4962 /* Ignore also local symbols and undefined symbols. */
4963 if (! (*s->bed->elf_hash_symbol) (h))
4964 return TRUE;
4966 name = h->root.root.string;
4967 p = strchr (name, ELF_VER_CHR);
4968 if (p != NULL)
4970 alc = bfd_malloc (p - name + 1);
4971 memcpy (alc, name, p - name);
4972 alc[p - name] = '\0';
4973 name = alc;
4976 /* Compute the hash value. */
4977 ha = bfd_elf_gnu_hash (name);
4979 /* Store the found hash value in the array for compute_bucket_count,
4980 and also for .dynsym reordering purposes. */
4981 s->hashcodes[s->nsyms] = ha;
4982 s->hashval[h->dynindx] = ha;
4983 ++s->nsyms;
4984 if (s->min_dynindx < 0 || s->min_dynindx > h->dynindx)
4985 s->min_dynindx = h->dynindx;
4987 if (alc != NULL)
4988 free (alc);
4990 return TRUE;
4993 /* This function will be called though elf_link_hash_traverse to do
4994 final dynaminc symbol renumbering. */
4996 static bfd_boolean
4997 elf_renumber_gnu_hash_syms (struct elf_link_hash_entry *h, void *data)
4999 struct collect_gnu_hash_codes *s = data;
5000 unsigned long int bucket;
5001 unsigned long int val;
5003 if (h->root.type == bfd_link_hash_warning)
5004 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5006 /* Ignore indirect symbols. */
5007 if (h->dynindx == -1)
5008 return TRUE;
5010 /* Ignore also local symbols and undefined symbols. */
5011 if (! (*s->bed->elf_hash_symbol) (h))
5013 if (h->dynindx >= s->min_dynindx)
5014 h->dynindx = s->local_indx++;
5015 return TRUE;
5018 bucket = s->hashval[h->dynindx] % s->bucketcount;
5019 val = (s->hashval[h->dynindx] >> s->shift1)
5020 & ((s->maskbits >> s->shift1) - 1);
5021 s->bitmask[val] |= ((bfd_vma) 1) << (s->hashval[h->dynindx] & s->mask);
5022 s->bitmask[val]
5023 |= ((bfd_vma) 1) << ((s->hashval[h->dynindx] >> s->shift2) & s->mask);
5024 val = s->hashval[h->dynindx] & ~(unsigned long int) 1;
5025 if (s->counts[bucket] == 1)
5026 /* Last element terminates the chain. */
5027 val |= 1;
5028 bfd_put_32 (s->output_bfd, val,
5029 s->contents + (s->indx[bucket] - s->symindx) * 4);
5030 --s->counts[bucket];
5031 h->dynindx = s->indx[bucket]++;
5032 return TRUE;
5035 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
5037 bfd_boolean
5038 _bfd_elf_hash_symbol (struct elf_link_hash_entry *h)
5040 return !(h->forced_local
5041 || h->root.type == bfd_link_hash_undefined
5042 || h->root.type == bfd_link_hash_undefweak
5043 || ((h->root.type == bfd_link_hash_defined
5044 || h->root.type == bfd_link_hash_defweak)
5045 && h->root.u.def.section->output_section == NULL));
5048 /* Array used to determine the number of hash table buckets to use
5049 based on the number of symbols there are. If there are fewer than
5050 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
5051 fewer than 37 we use 17 buckets, and so forth. We never use more
5052 than 32771 buckets. */
5054 static const size_t elf_buckets[] =
5056 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
5057 16411, 32771, 0
5060 /* Compute bucket count for hashing table. We do not use a static set
5061 of possible tables sizes anymore. Instead we determine for all
5062 possible reasonable sizes of the table the outcome (i.e., the
5063 number of collisions etc) and choose the best solution. The
5064 weighting functions are not too simple to allow the table to grow
5065 without bounds. Instead one of the weighting factors is the size.
5066 Therefore the result is always a good payoff between few collisions
5067 (= short chain lengths) and table size. */
5068 static size_t
5069 compute_bucket_count (struct bfd_link_info *info, unsigned long int *hashcodes,
5070 unsigned long int nsyms, int gnu_hash)
5072 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
5073 size_t best_size = 0;
5074 unsigned long int i;
5075 bfd_size_type amt;
5077 /* We have a problem here. The following code to optimize the table
5078 size requires an integer type with more the 32 bits. If
5079 BFD_HOST_U_64_BIT is set we know about such a type. */
5080 #ifdef BFD_HOST_U_64_BIT
5081 if (info->optimize)
5083 size_t minsize;
5084 size_t maxsize;
5085 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
5086 bfd *dynobj = elf_hash_table (info)->dynobj;
5087 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
5088 unsigned long int *counts;
5090 /* Possible optimization parameters: if we have NSYMS symbols we say
5091 that the hashing table must at least have NSYMS/4 and at most
5092 2*NSYMS buckets. */
5093 minsize = nsyms / 4;
5094 if (minsize == 0)
5095 minsize = 1;
5096 best_size = maxsize = nsyms * 2;
5097 if (gnu_hash)
5099 if (minsize < 2)
5100 minsize = 2;
5101 if ((best_size & 31) == 0)
5102 ++best_size;
5105 /* Create array where we count the collisions in. We must use bfd_malloc
5106 since the size could be large. */
5107 amt = maxsize;
5108 amt *= sizeof (unsigned long int);
5109 counts = bfd_malloc (amt);
5110 if (counts == NULL)
5111 return 0;
5113 /* Compute the "optimal" size for the hash table. The criteria is a
5114 minimal chain length. The minor criteria is (of course) the size
5115 of the table. */
5116 for (i = minsize; i < maxsize; ++i)
5118 /* Walk through the array of hashcodes and count the collisions. */
5119 BFD_HOST_U_64_BIT max;
5120 unsigned long int j;
5121 unsigned long int fact;
5123 if (gnu_hash && (i & 31) == 0)
5124 continue;
5126 memset (counts, '\0', i * sizeof (unsigned long int));
5128 /* Determine how often each hash bucket is used. */
5129 for (j = 0; j < nsyms; ++j)
5130 ++counts[hashcodes[j] % i];
5132 /* For the weight function we need some information about the
5133 pagesize on the target. This is information need not be 100%
5134 accurate. Since this information is not available (so far) we
5135 define it here to a reasonable default value. If it is crucial
5136 to have a better value some day simply define this value. */
5137 # ifndef BFD_TARGET_PAGESIZE
5138 # define BFD_TARGET_PAGESIZE (4096)
5139 # endif
5141 /* We in any case need 2 + DYNSYMCOUNT entries for the size values
5142 and the chains. */
5143 max = (2 + dynsymcount) * bed->s->sizeof_hash_entry;
5145 # if 1
5146 /* Variant 1: optimize for short chains. We add the squares
5147 of all the chain lengths (which favors many small chain
5148 over a few long chains). */
5149 for (j = 0; j < i; ++j)
5150 max += counts[j] * counts[j];
5152 /* This adds penalties for the overall size of the table. */
5153 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5154 max *= fact * fact;
5155 # else
5156 /* Variant 2: Optimize a lot more for small table. Here we
5157 also add squares of the size but we also add penalties for
5158 empty slots (the +1 term). */
5159 for (j = 0; j < i; ++j)
5160 max += (1 + counts[j]) * (1 + counts[j]);
5162 /* The overall size of the table is considered, but not as
5163 strong as in variant 1, where it is squared. */
5164 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5165 max *= fact;
5166 # endif
5168 /* Compare with current best results. */
5169 if (max < best_chlen)
5171 best_chlen = max;
5172 best_size = i;
5176 free (counts);
5178 else
5179 #endif /* defined (BFD_HOST_U_64_BIT) */
5181 /* This is the fallback solution if no 64bit type is available or if we
5182 are not supposed to spend much time on optimizations. We select the
5183 bucket count using a fixed set of numbers. */
5184 for (i = 0; elf_buckets[i] != 0; i++)
5186 best_size = elf_buckets[i];
5187 if (nsyms < elf_buckets[i + 1])
5188 break;
5190 if (gnu_hash && best_size < 2)
5191 best_size = 2;
5194 return best_size;
5197 /* Set up the sizes and contents of the ELF dynamic sections. This is
5198 called by the ELF linker emulation before_allocation routine. We
5199 must set the sizes of the sections before the linker sets the
5200 addresses of the various sections. */
5202 bfd_boolean
5203 bfd_elf_size_dynamic_sections (bfd *output_bfd,
5204 const char *soname,
5205 const char *rpath,
5206 const char *filter_shlib,
5207 const char * const *auxiliary_filters,
5208 struct bfd_link_info *info,
5209 asection **sinterpptr,
5210 struct bfd_elf_version_tree *verdefs)
5212 bfd_size_type soname_indx;
5213 bfd *dynobj;
5214 const struct elf_backend_data *bed;
5215 struct elf_assign_sym_version_info asvinfo;
5217 *sinterpptr = NULL;
5219 soname_indx = (bfd_size_type) -1;
5221 if (!is_elf_hash_table (info->hash))
5222 return TRUE;
5224 elf_tdata (output_bfd)->relro = info->relro;
5225 if (info->execstack)
5226 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
5227 else if (info->noexecstack)
5228 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
5229 else
5231 bfd *inputobj;
5232 asection *notesec = NULL;
5233 int exec = 0;
5235 for (inputobj = info->input_bfds;
5236 inputobj;
5237 inputobj = inputobj->link_next)
5239 asection *s;
5241 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
5242 continue;
5243 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
5244 if (s)
5246 if (s->flags & SEC_CODE)
5247 exec = PF_X;
5248 notesec = s;
5250 else
5251 exec = PF_X;
5253 if (notesec)
5255 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
5256 if (exec && info->relocatable
5257 && notesec->output_section != bfd_abs_section_ptr)
5258 notesec->output_section->flags |= SEC_CODE;
5262 /* Any syms created from now on start with -1 in
5263 got.refcount/offset and plt.refcount/offset. */
5264 elf_hash_table (info)->init_got_refcount
5265 = elf_hash_table (info)->init_got_offset;
5266 elf_hash_table (info)->init_plt_refcount
5267 = elf_hash_table (info)->init_plt_offset;
5269 /* The backend may have to create some sections regardless of whether
5270 we're dynamic or not. */
5271 bed = get_elf_backend_data (output_bfd);
5272 if (bed->elf_backend_always_size_sections
5273 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
5274 return FALSE;
5276 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5277 return FALSE;
5279 dynobj = elf_hash_table (info)->dynobj;
5281 /* If there were no dynamic objects in the link, there is nothing to
5282 do here. */
5283 if (dynobj == NULL)
5284 return TRUE;
5286 if (elf_hash_table (info)->dynamic_sections_created)
5288 struct elf_info_failed eif;
5289 struct elf_link_hash_entry *h;
5290 asection *dynstr;
5291 struct bfd_elf_version_tree *t;
5292 struct bfd_elf_version_expr *d;
5293 asection *s;
5294 bfd_boolean all_defined;
5296 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5297 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5299 if (soname != NULL)
5301 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5302 soname, TRUE);
5303 if (soname_indx == (bfd_size_type) -1
5304 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5305 return FALSE;
5308 if (info->symbolic)
5310 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5311 return FALSE;
5312 info->flags |= DF_SYMBOLIC;
5315 if (rpath != NULL)
5317 bfd_size_type indx;
5319 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5320 TRUE);
5321 if (indx == (bfd_size_type) -1
5322 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5323 return FALSE;
5325 if (info->new_dtags)
5327 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5328 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5329 return FALSE;
5333 if (filter_shlib != NULL)
5335 bfd_size_type indx;
5337 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5338 filter_shlib, TRUE);
5339 if (indx == (bfd_size_type) -1
5340 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5341 return FALSE;
5344 if (auxiliary_filters != NULL)
5346 const char * const *p;
5348 for (p = auxiliary_filters; *p != NULL; p++)
5350 bfd_size_type indx;
5352 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5353 *p, TRUE);
5354 if (indx == (bfd_size_type) -1
5355 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5356 return FALSE;
5360 eif.info = info;
5361 eif.verdefs = verdefs;
5362 eif.failed = FALSE;
5364 /* If we are supposed to export all symbols into the dynamic symbol
5365 table (this is not the normal case), then do so. */
5366 if (info->export_dynamic
5367 || (info->executable && info->dynamic))
5369 elf_link_hash_traverse (elf_hash_table (info),
5370 _bfd_elf_export_symbol,
5371 &eif);
5372 if (eif.failed)
5373 return FALSE;
5376 /* Make all global versions with definition. */
5377 for (t = verdefs; t != NULL; t = t->next)
5378 for (d = t->globals.list; d != NULL; d = d->next)
5379 if (!d->symver && d->symbol)
5381 const char *verstr, *name;
5382 size_t namelen, verlen, newlen;
5383 char *newname, *p;
5384 struct elf_link_hash_entry *newh;
5386 name = d->symbol;
5387 namelen = strlen (name);
5388 verstr = t->name;
5389 verlen = strlen (verstr);
5390 newlen = namelen + verlen + 3;
5392 newname = bfd_malloc (newlen);
5393 if (newname == NULL)
5394 return FALSE;
5395 memcpy (newname, name, namelen);
5397 /* Check the hidden versioned definition. */
5398 p = newname + namelen;
5399 *p++ = ELF_VER_CHR;
5400 memcpy (p, verstr, verlen + 1);
5401 newh = elf_link_hash_lookup (elf_hash_table (info),
5402 newname, FALSE, FALSE,
5403 FALSE);
5404 if (newh == NULL
5405 || (newh->root.type != bfd_link_hash_defined
5406 && newh->root.type != bfd_link_hash_defweak))
5408 /* Check the default versioned definition. */
5409 *p++ = ELF_VER_CHR;
5410 memcpy (p, verstr, verlen + 1);
5411 newh = elf_link_hash_lookup (elf_hash_table (info),
5412 newname, FALSE, FALSE,
5413 FALSE);
5415 free (newname);
5417 /* Mark this version if there is a definition and it is
5418 not defined in a shared object. */
5419 if (newh != NULL
5420 && !newh->def_dynamic
5421 && (newh->root.type == bfd_link_hash_defined
5422 || newh->root.type == bfd_link_hash_defweak))
5423 d->symver = 1;
5426 /* Attach all the symbols to their version information. */
5427 asvinfo.output_bfd = output_bfd;
5428 asvinfo.info = info;
5429 asvinfo.verdefs = verdefs;
5430 asvinfo.failed = FALSE;
5432 elf_link_hash_traverse (elf_hash_table (info),
5433 _bfd_elf_link_assign_sym_version,
5434 &asvinfo);
5435 if (asvinfo.failed)
5436 return FALSE;
5438 if (!info->allow_undefined_version)
5440 /* Check if all global versions have a definition. */
5441 all_defined = TRUE;
5442 for (t = verdefs; t != NULL; t = t->next)
5443 for (d = t->globals.list; d != NULL; d = d->next)
5444 if (!d->symver && !d->script)
5446 (*_bfd_error_handler)
5447 (_("%s: undefined version: %s"),
5448 d->pattern, t->name);
5449 all_defined = FALSE;
5452 if (!all_defined)
5454 bfd_set_error (bfd_error_bad_value);
5455 return FALSE;
5459 /* Find all symbols which were defined in a dynamic object and make
5460 the backend pick a reasonable value for them. */
5461 elf_link_hash_traverse (elf_hash_table (info),
5462 _bfd_elf_adjust_dynamic_symbol,
5463 &eif);
5464 if (eif.failed)
5465 return FALSE;
5467 /* Add some entries to the .dynamic section. We fill in some of the
5468 values later, in bfd_elf_final_link, but we must add the entries
5469 now so that we know the final size of the .dynamic section. */
5471 /* If there are initialization and/or finalization functions to
5472 call then add the corresponding DT_INIT/DT_FINI entries. */
5473 h = (info->init_function
5474 ? elf_link_hash_lookup (elf_hash_table (info),
5475 info->init_function, FALSE,
5476 FALSE, FALSE)
5477 : NULL);
5478 if (h != NULL
5479 && (h->ref_regular
5480 || h->def_regular))
5482 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5483 return FALSE;
5485 h = (info->fini_function
5486 ? elf_link_hash_lookup (elf_hash_table (info),
5487 info->fini_function, FALSE,
5488 FALSE, FALSE)
5489 : NULL);
5490 if (h != NULL
5491 && (h->ref_regular
5492 || h->def_regular))
5494 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5495 return FALSE;
5498 s = bfd_get_section_by_name (output_bfd, ".preinit_array");
5499 if (s != NULL && s->linker_has_input)
5501 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5502 if (! info->executable)
5504 bfd *sub;
5505 asection *o;
5507 for (sub = info->input_bfds; sub != NULL;
5508 sub = sub->link_next)
5509 for (o = sub->sections; o != NULL; o = o->next)
5510 if (elf_section_data (o)->this_hdr.sh_type
5511 == SHT_PREINIT_ARRAY)
5513 (*_bfd_error_handler)
5514 (_("%B: .preinit_array section is not allowed in DSO"),
5515 sub);
5516 break;
5519 bfd_set_error (bfd_error_nonrepresentable_section);
5520 return FALSE;
5523 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5524 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5525 return FALSE;
5527 s = bfd_get_section_by_name (output_bfd, ".init_array");
5528 if (s != NULL && s->linker_has_input)
5530 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5531 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5532 return FALSE;
5534 s = bfd_get_section_by_name (output_bfd, ".fini_array");
5535 if (s != NULL && s->linker_has_input)
5537 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5538 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5539 return FALSE;
5542 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5543 /* If .dynstr is excluded from the link, we don't want any of
5544 these tags. Strictly, we should be checking each section
5545 individually; This quick check covers for the case where
5546 someone does a /DISCARD/ : { *(*) }. */
5547 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5549 bfd_size_type strsize;
5551 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5552 if ((info->emit_hash
5553 && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
5554 || (info->emit_gnu_hash
5555 && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0))
5556 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5557 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5558 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5559 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5560 bed->s->sizeof_sym))
5561 return FALSE;
5565 /* The backend must work out the sizes of all the other dynamic
5566 sections. */
5567 if (bed->elf_backend_size_dynamic_sections
5568 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5569 return FALSE;
5571 if (elf_hash_table (info)->dynamic_sections_created)
5573 unsigned long section_sym_count;
5574 asection *s;
5576 /* Set up the version definition section. */
5577 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5578 BFD_ASSERT (s != NULL);
5580 /* We may have created additional version definitions if we are
5581 just linking a regular application. */
5582 verdefs = asvinfo.verdefs;
5584 /* Skip anonymous version tag. */
5585 if (verdefs != NULL && verdefs->vernum == 0)
5586 verdefs = verdefs->next;
5588 if (verdefs == NULL && !info->create_default_symver)
5589 s->flags |= SEC_EXCLUDE;
5590 else
5592 unsigned int cdefs;
5593 bfd_size_type size;
5594 struct bfd_elf_version_tree *t;
5595 bfd_byte *p;
5596 Elf_Internal_Verdef def;
5597 Elf_Internal_Verdaux defaux;
5598 struct bfd_link_hash_entry *bh;
5599 struct elf_link_hash_entry *h;
5600 const char *name;
5602 cdefs = 0;
5603 size = 0;
5605 /* Make space for the base version. */
5606 size += sizeof (Elf_External_Verdef);
5607 size += sizeof (Elf_External_Verdaux);
5608 ++cdefs;
5610 /* Make space for the default version. */
5611 if (info->create_default_symver)
5613 size += sizeof (Elf_External_Verdef);
5614 ++cdefs;
5617 for (t = verdefs; t != NULL; t = t->next)
5619 struct bfd_elf_version_deps *n;
5621 size += sizeof (Elf_External_Verdef);
5622 size += sizeof (Elf_External_Verdaux);
5623 ++cdefs;
5625 for (n = t->deps; n != NULL; n = n->next)
5626 size += sizeof (Elf_External_Verdaux);
5629 s->size = size;
5630 s->contents = bfd_alloc (output_bfd, s->size);
5631 if (s->contents == NULL && s->size != 0)
5632 return FALSE;
5634 /* Fill in the version definition section. */
5636 p = s->contents;
5638 def.vd_version = VER_DEF_CURRENT;
5639 def.vd_flags = VER_FLG_BASE;
5640 def.vd_ndx = 1;
5641 def.vd_cnt = 1;
5642 if (info->create_default_symver)
5644 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5645 def.vd_next = sizeof (Elf_External_Verdef);
5647 else
5649 def.vd_aux = sizeof (Elf_External_Verdef);
5650 def.vd_next = (sizeof (Elf_External_Verdef)
5651 + sizeof (Elf_External_Verdaux));
5654 if (soname_indx != (bfd_size_type) -1)
5656 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5657 soname_indx);
5658 def.vd_hash = bfd_elf_hash (soname);
5659 defaux.vda_name = soname_indx;
5660 name = soname;
5662 else
5664 bfd_size_type indx;
5666 name = lbasename (output_bfd->filename);
5667 def.vd_hash = bfd_elf_hash (name);
5668 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5669 name, FALSE);
5670 if (indx == (bfd_size_type) -1)
5671 return FALSE;
5672 defaux.vda_name = indx;
5674 defaux.vda_next = 0;
5676 _bfd_elf_swap_verdef_out (output_bfd, &def,
5677 (Elf_External_Verdef *) p);
5678 p += sizeof (Elf_External_Verdef);
5679 if (info->create_default_symver)
5681 /* Add a symbol representing this version. */
5682 bh = NULL;
5683 if (! (_bfd_generic_link_add_one_symbol
5684 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5685 0, NULL, FALSE,
5686 get_elf_backend_data (dynobj)->collect, &bh)))
5687 return FALSE;
5688 h = (struct elf_link_hash_entry *) bh;
5689 h->non_elf = 0;
5690 h->def_regular = 1;
5691 h->type = STT_OBJECT;
5692 h->verinfo.vertree = NULL;
5694 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5695 return FALSE;
5697 /* Create a duplicate of the base version with the same
5698 aux block, but different flags. */
5699 def.vd_flags = 0;
5700 def.vd_ndx = 2;
5701 def.vd_aux = sizeof (Elf_External_Verdef);
5702 if (verdefs)
5703 def.vd_next = (sizeof (Elf_External_Verdef)
5704 + sizeof (Elf_External_Verdaux));
5705 else
5706 def.vd_next = 0;
5707 _bfd_elf_swap_verdef_out (output_bfd, &def,
5708 (Elf_External_Verdef *) p);
5709 p += sizeof (Elf_External_Verdef);
5711 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5712 (Elf_External_Verdaux *) p);
5713 p += sizeof (Elf_External_Verdaux);
5715 for (t = verdefs; t != NULL; t = t->next)
5717 unsigned int cdeps;
5718 struct bfd_elf_version_deps *n;
5720 cdeps = 0;
5721 for (n = t->deps; n != NULL; n = n->next)
5722 ++cdeps;
5724 /* Add a symbol representing this version. */
5725 bh = NULL;
5726 if (! (_bfd_generic_link_add_one_symbol
5727 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5728 0, NULL, FALSE,
5729 get_elf_backend_data (dynobj)->collect, &bh)))
5730 return FALSE;
5731 h = (struct elf_link_hash_entry *) bh;
5732 h->non_elf = 0;
5733 h->def_regular = 1;
5734 h->type = STT_OBJECT;
5735 h->verinfo.vertree = t;
5737 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5738 return FALSE;
5740 def.vd_version = VER_DEF_CURRENT;
5741 def.vd_flags = 0;
5742 if (t->globals.list == NULL
5743 && t->locals.list == NULL
5744 && ! t->used)
5745 def.vd_flags |= VER_FLG_WEAK;
5746 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5747 def.vd_cnt = cdeps + 1;
5748 def.vd_hash = bfd_elf_hash (t->name);
5749 def.vd_aux = sizeof (Elf_External_Verdef);
5750 def.vd_next = 0;
5751 if (t->next != NULL)
5752 def.vd_next = (sizeof (Elf_External_Verdef)
5753 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5755 _bfd_elf_swap_verdef_out (output_bfd, &def,
5756 (Elf_External_Verdef *) p);
5757 p += sizeof (Elf_External_Verdef);
5759 defaux.vda_name = h->dynstr_index;
5760 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5761 h->dynstr_index);
5762 defaux.vda_next = 0;
5763 if (t->deps != NULL)
5764 defaux.vda_next = sizeof (Elf_External_Verdaux);
5765 t->name_indx = defaux.vda_name;
5767 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5768 (Elf_External_Verdaux *) p);
5769 p += sizeof (Elf_External_Verdaux);
5771 for (n = t->deps; n != NULL; n = n->next)
5773 if (n->version_needed == NULL)
5775 /* This can happen if there was an error in the
5776 version script. */
5777 defaux.vda_name = 0;
5779 else
5781 defaux.vda_name = n->version_needed->name_indx;
5782 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5783 defaux.vda_name);
5785 if (n->next == NULL)
5786 defaux.vda_next = 0;
5787 else
5788 defaux.vda_next = sizeof (Elf_External_Verdaux);
5790 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5791 (Elf_External_Verdaux *) p);
5792 p += sizeof (Elf_External_Verdaux);
5796 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5797 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5798 return FALSE;
5800 elf_tdata (output_bfd)->cverdefs = cdefs;
5803 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5805 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5806 return FALSE;
5808 else if (info->flags & DF_BIND_NOW)
5810 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5811 return FALSE;
5814 if (info->flags_1)
5816 if (info->executable)
5817 info->flags_1 &= ~ (DF_1_INITFIRST
5818 | DF_1_NODELETE
5819 | DF_1_NOOPEN);
5820 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5821 return FALSE;
5824 /* Work out the size of the version reference section. */
5826 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5827 BFD_ASSERT (s != NULL);
5829 struct elf_find_verdep_info sinfo;
5831 sinfo.output_bfd = output_bfd;
5832 sinfo.info = info;
5833 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5834 if (sinfo.vers == 0)
5835 sinfo.vers = 1;
5836 sinfo.failed = FALSE;
5838 elf_link_hash_traverse (elf_hash_table (info),
5839 _bfd_elf_link_find_version_dependencies,
5840 &sinfo);
5842 if (elf_tdata (output_bfd)->verref == NULL)
5843 s->flags |= SEC_EXCLUDE;
5844 else
5846 Elf_Internal_Verneed *t;
5847 unsigned int size;
5848 unsigned int crefs;
5849 bfd_byte *p;
5851 /* Build the version definition section. */
5852 size = 0;
5853 crefs = 0;
5854 for (t = elf_tdata (output_bfd)->verref;
5855 t != NULL;
5856 t = t->vn_nextref)
5858 Elf_Internal_Vernaux *a;
5860 size += sizeof (Elf_External_Verneed);
5861 ++crefs;
5862 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5863 size += sizeof (Elf_External_Vernaux);
5866 s->size = size;
5867 s->contents = bfd_alloc (output_bfd, s->size);
5868 if (s->contents == NULL)
5869 return FALSE;
5871 p = s->contents;
5872 for (t = elf_tdata (output_bfd)->verref;
5873 t != NULL;
5874 t = t->vn_nextref)
5876 unsigned int caux;
5877 Elf_Internal_Vernaux *a;
5878 bfd_size_type indx;
5880 caux = 0;
5881 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5882 ++caux;
5884 t->vn_version = VER_NEED_CURRENT;
5885 t->vn_cnt = caux;
5886 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5887 elf_dt_name (t->vn_bfd) != NULL
5888 ? elf_dt_name (t->vn_bfd)
5889 : lbasename (t->vn_bfd->filename),
5890 FALSE);
5891 if (indx == (bfd_size_type) -1)
5892 return FALSE;
5893 t->vn_file = indx;
5894 t->vn_aux = sizeof (Elf_External_Verneed);
5895 if (t->vn_nextref == NULL)
5896 t->vn_next = 0;
5897 else
5898 t->vn_next = (sizeof (Elf_External_Verneed)
5899 + caux * sizeof (Elf_External_Vernaux));
5901 _bfd_elf_swap_verneed_out (output_bfd, t,
5902 (Elf_External_Verneed *) p);
5903 p += sizeof (Elf_External_Verneed);
5905 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5907 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5908 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5909 a->vna_nodename, FALSE);
5910 if (indx == (bfd_size_type) -1)
5911 return FALSE;
5912 a->vna_name = indx;
5913 if (a->vna_nextptr == NULL)
5914 a->vna_next = 0;
5915 else
5916 a->vna_next = sizeof (Elf_External_Vernaux);
5918 _bfd_elf_swap_vernaux_out (output_bfd, a,
5919 (Elf_External_Vernaux *) p);
5920 p += sizeof (Elf_External_Vernaux);
5924 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5925 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5926 return FALSE;
5928 elf_tdata (output_bfd)->cverrefs = crefs;
5932 if ((elf_tdata (output_bfd)->cverrefs == 0
5933 && elf_tdata (output_bfd)->cverdefs == 0)
5934 || _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5935 &section_sym_count) == 0)
5937 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5938 s->flags |= SEC_EXCLUDE;
5941 return TRUE;
5944 /* Find the first non-excluded output section. We'll use its
5945 section symbol for some emitted relocs. */
5946 void
5947 _bfd_elf_init_1_index_section (bfd *output_bfd, struct bfd_link_info *info)
5949 asection *s;
5951 for (s = output_bfd->sections; s != NULL; s = s->next)
5952 if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
5953 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
5955 elf_hash_table (info)->text_index_section = s;
5956 break;
5960 /* Find two non-excluded output sections, one for code, one for data.
5961 We'll use their section symbols for some emitted relocs. */
5962 void
5963 _bfd_elf_init_2_index_sections (bfd *output_bfd, struct bfd_link_info *info)
5965 asection *s;
5967 for (s = output_bfd->sections; s != NULL; s = s->next)
5968 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY))
5969 == (SEC_ALLOC | SEC_READONLY))
5970 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
5972 elf_hash_table (info)->text_index_section = s;
5973 break;
5976 for (s = output_bfd->sections; s != NULL; s = s->next)
5977 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY)) == SEC_ALLOC)
5978 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
5980 elf_hash_table (info)->data_index_section = s;
5981 break;
5984 if (elf_hash_table (info)->text_index_section == NULL)
5985 elf_hash_table (info)->text_index_section
5986 = elf_hash_table (info)->data_index_section;
5989 bfd_boolean
5990 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
5992 const struct elf_backend_data *bed;
5994 if (!is_elf_hash_table (info->hash))
5995 return TRUE;
5997 bed = get_elf_backend_data (output_bfd);
5998 (*bed->elf_backend_init_index_section) (output_bfd, info);
6000 if (elf_hash_table (info)->dynamic_sections_created)
6002 bfd *dynobj;
6003 asection *s;
6004 bfd_size_type dynsymcount;
6005 unsigned long section_sym_count;
6006 unsigned int dtagcount;
6008 dynobj = elf_hash_table (info)->dynobj;
6010 /* Assign dynsym indicies. In a shared library we generate a
6011 section symbol for each output section, which come first.
6012 Next come all of the back-end allocated local dynamic syms,
6013 followed by the rest of the global symbols. */
6015 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
6016 &section_sym_count);
6018 /* Work out the size of the symbol version section. */
6019 s = bfd_get_section_by_name (dynobj, ".gnu.version");
6020 BFD_ASSERT (s != NULL);
6021 if (dynsymcount != 0
6022 && (s->flags & SEC_EXCLUDE) == 0)
6024 s->size = dynsymcount * sizeof (Elf_External_Versym);
6025 s->contents = bfd_zalloc (output_bfd, s->size);
6026 if (s->contents == NULL)
6027 return FALSE;
6029 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
6030 return FALSE;
6033 /* Set the size of the .dynsym and .hash sections. We counted
6034 the number of dynamic symbols in elf_link_add_object_symbols.
6035 We will build the contents of .dynsym and .hash when we build
6036 the final symbol table, because until then we do not know the
6037 correct value to give the symbols. We built the .dynstr
6038 section as we went along in elf_link_add_object_symbols. */
6039 s = bfd_get_section_by_name (dynobj, ".dynsym");
6040 BFD_ASSERT (s != NULL);
6041 s->size = dynsymcount * bed->s->sizeof_sym;
6043 if (dynsymcount != 0)
6045 s->contents = bfd_alloc (output_bfd, s->size);
6046 if (s->contents == NULL)
6047 return FALSE;
6049 /* The first entry in .dynsym is a dummy symbol.
6050 Clear all the section syms, in case we don't output them all. */
6051 ++section_sym_count;
6052 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
6055 elf_hash_table (info)->bucketcount = 0;
6057 /* Compute the size of the hashing table. As a side effect this
6058 computes the hash values for all the names we export. */
6059 if (info->emit_hash)
6061 unsigned long int *hashcodes;
6062 unsigned long int *hashcodesp;
6063 bfd_size_type amt;
6064 unsigned long int nsyms;
6065 size_t bucketcount;
6066 size_t hash_entry_size;
6068 /* Compute the hash values for all exported symbols. At the same
6069 time store the values in an array so that we could use them for
6070 optimizations. */
6071 amt = dynsymcount * sizeof (unsigned long int);
6072 hashcodes = bfd_malloc (amt);
6073 if (hashcodes == NULL)
6074 return FALSE;
6075 hashcodesp = hashcodes;
6077 /* Put all hash values in HASHCODES. */
6078 elf_link_hash_traverse (elf_hash_table (info),
6079 elf_collect_hash_codes, &hashcodesp);
6081 nsyms = hashcodesp - hashcodes;
6082 bucketcount
6083 = compute_bucket_count (info, hashcodes, nsyms, 0);
6084 free (hashcodes);
6086 if (bucketcount == 0)
6087 return FALSE;
6089 elf_hash_table (info)->bucketcount = bucketcount;
6091 s = bfd_get_section_by_name (dynobj, ".hash");
6092 BFD_ASSERT (s != NULL);
6093 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
6094 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
6095 s->contents = bfd_zalloc (output_bfd, s->size);
6096 if (s->contents == NULL)
6097 return FALSE;
6099 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
6100 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
6101 s->contents + hash_entry_size);
6104 if (info->emit_gnu_hash)
6106 size_t i, cnt;
6107 unsigned char *contents;
6108 struct collect_gnu_hash_codes cinfo;
6109 bfd_size_type amt;
6110 size_t bucketcount;
6112 memset (&cinfo, 0, sizeof (cinfo));
6114 /* Compute the hash values for all exported symbols. At the same
6115 time store the values in an array so that we could use them for
6116 optimizations. */
6117 amt = dynsymcount * 2 * sizeof (unsigned long int);
6118 cinfo.hashcodes = bfd_malloc (amt);
6119 if (cinfo.hashcodes == NULL)
6120 return FALSE;
6122 cinfo.hashval = cinfo.hashcodes + dynsymcount;
6123 cinfo.min_dynindx = -1;
6124 cinfo.output_bfd = output_bfd;
6125 cinfo.bed = bed;
6127 /* Put all hash values in HASHCODES. */
6128 elf_link_hash_traverse (elf_hash_table (info),
6129 elf_collect_gnu_hash_codes, &cinfo);
6131 bucketcount
6132 = compute_bucket_count (info, cinfo.hashcodes, cinfo.nsyms, 1);
6134 if (bucketcount == 0)
6136 free (cinfo.hashcodes);
6137 return FALSE;
6140 s = bfd_get_section_by_name (dynobj, ".gnu.hash");
6141 BFD_ASSERT (s != NULL);
6143 if (cinfo.nsyms == 0)
6145 /* Empty .gnu.hash section is special. */
6146 BFD_ASSERT (cinfo.min_dynindx == -1);
6147 free (cinfo.hashcodes);
6148 s->size = 5 * 4 + bed->s->arch_size / 8;
6149 contents = bfd_zalloc (output_bfd, s->size);
6150 if (contents == NULL)
6151 return FALSE;
6152 s->contents = contents;
6153 /* 1 empty bucket. */
6154 bfd_put_32 (output_bfd, 1, contents);
6155 /* SYMIDX above the special symbol 0. */
6156 bfd_put_32 (output_bfd, 1, contents + 4);
6157 /* Just one word for bitmask. */
6158 bfd_put_32 (output_bfd, 1, contents + 8);
6159 /* Only hash fn bloom filter. */
6160 bfd_put_32 (output_bfd, 0, contents + 12);
6161 /* No hashes are valid - empty bitmask. */
6162 bfd_put (bed->s->arch_size, output_bfd, 0, contents + 16);
6163 /* No hashes in the only bucket. */
6164 bfd_put_32 (output_bfd, 0,
6165 contents + 16 + bed->s->arch_size / 8);
6167 else
6169 unsigned long int maskwords, maskbitslog2;
6170 BFD_ASSERT (cinfo.min_dynindx != -1);
6172 maskbitslog2 = bfd_log2 (cinfo.nsyms) + 1;
6173 if (maskbitslog2 < 3)
6174 maskbitslog2 = 5;
6175 else if ((1 << (maskbitslog2 - 2)) & cinfo.nsyms)
6176 maskbitslog2 = maskbitslog2 + 3;
6177 else
6178 maskbitslog2 = maskbitslog2 + 2;
6179 if (bed->s->arch_size == 64)
6181 if (maskbitslog2 == 5)
6182 maskbitslog2 = 6;
6183 cinfo.shift1 = 6;
6185 else
6186 cinfo.shift1 = 5;
6187 cinfo.mask = (1 << cinfo.shift1) - 1;
6188 cinfo.shift2 = maskbitslog2;
6189 cinfo.maskbits = 1 << maskbitslog2;
6190 maskwords = 1 << (maskbitslog2 - cinfo.shift1);
6191 amt = bucketcount * sizeof (unsigned long int) * 2;
6192 amt += maskwords * sizeof (bfd_vma);
6193 cinfo.bitmask = bfd_malloc (amt);
6194 if (cinfo.bitmask == NULL)
6196 free (cinfo.hashcodes);
6197 return FALSE;
6200 cinfo.counts = (void *) (cinfo.bitmask + maskwords);
6201 cinfo.indx = cinfo.counts + bucketcount;
6202 cinfo.symindx = dynsymcount - cinfo.nsyms;
6203 memset (cinfo.bitmask, 0, maskwords * sizeof (bfd_vma));
6205 /* Determine how often each hash bucket is used. */
6206 memset (cinfo.counts, 0, bucketcount * sizeof (cinfo.counts[0]));
6207 for (i = 0; i < cinfo.nsyms; ++i)
6208 ++cinfo.counts[cinfo.hashcodes[i] % bucketcount];
6210 for (i = 0, cnt = cinfo.symindx; i < bucketcount; ++i)
6211 if (cinfo.counts[i] != 0)
6213 cinfo.indx[i] = cnt;
6214 cnt += cinfo.counts[i];
6216 BFD_ASSERT (cnt == dynsymcount);
6217 cinfo.bucketcount = bucketcount;
6218 cinfo.local_indx = cinfo.min_dynindx;
6220 s->size = (4 + bucketcount + cinfo.nsyms) * 4;
6221 s->size += cinfo.maskbits / 8;
6222 contents = bfd_zalloc (output_bfd, s->size);
6223 if (contents == NULL)
6225 free (cinfo.bitmask);
6226 free (cinfo.hashcodes);
6227 return FALSE;
6230 s->contents = contents;
6231 bfd_put_32 (output_bfd, bucketcount, contents);
6232 bfd_put_32 (output_bfd, cinfo.symindx, contents + 4);
6233 bfd_put_32 (output_bfd, maskwords, contents + 8);
6234 bfd_put_32 (output_bfd, cinfo.shift2, contents + 12);
6235 contents += 16 + cinfo.maskbits / 8;
6237 for (i = 0; i < bucketcount; ++i)
6239 if (cinfo.counts[i] == 0)
6240 bfd_put_32 (output_bfd, 0, contents);
6241 else
6242 bfd_put_32 (output_bfd, cinfo.indx[i], contents);
6243 contents += 4;
6246 cinfo.contents = contents;
6248 /* Renumber dynamic symbols, populate .gnu.hash section. */
6249 elf_link_hash_traverse (elf_hash_table (info),
6250 elf_renumber_gnu_hash_syms, &cinfo);
6252 contents = s->contents + 16;
6253 for (i = 0; i < maskwords; ++i)
6255 bfd_put (bed->s->arch_size, output_bfd, cinfo.bitmask[i],
6256 contents);
6257 contents += bed->s->arch_size / 8;
6260 free (cinfo.bitmask);
6261 free (cinfo.hashcodes);
6265 s = bfd_get_section_by_name (dynobj, ".dynstr");
6266 BFD_ASSERT (s != NULL);
6268 elf_finalize_dynstr (output_bfd, info);
6270 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
6272 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
6273 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
6274 return FALSE;
6277 return TRUE;
6280 /* Final phase of ELF linker. */
6282 /* A structure we use to avoid passing large numbers of arguments. */
6284 struct elf_final_link_info
6286 /* General link information. */
6287 struct bfd_link_info *info;
6288 /* Output BFD. */
6289 bfd *output_bfd;
6290 /* Symbol string table. */
6291 struct bfd_strtab_hash *symstrtab;
6292 /* .dynsym section. */
6293 asection *dynsym_sec;
6294 /* .hash section. */
6295 asection *hash_sec;
6296 /* symbol version section (.gnu.version). */
6297 asection *symver_sec;
6298 /* Buffer large enough to hold contents of any section. */
6299 bfd_byte *contents;
6300 /* Buffer large enough to hold external relocs of any section. */
6301 void *external_relocs;
6302 /* Buffer large enough to hold internal relocs of any section. */
6303 Elf_Internal_Rela *internal_relocs;
6304 /* Buffer large enough to hold external local symbols of any input
6305 BFD. */
6306 bfd_byte *external_syms;
6307 /* And a buffer for symbol section indices. */
6308 Elf_External_Sym_Shndx *locsym_shndx;
6309 /* Buffer large enough to hold internal local symbols of any input
6310 BFD. */
6311 Elf_Internal_Sym *internal_syms;
6312 /* Array large enough to hold a symbol index for each local symbol
6313 of any input BFD. */
6314 long *indices;
6315 /* Array large enough to hold a section pointer for each local
6316 symbol of any input BFD. */
6317 asection **sections;
6318 /* Buffer to hold swapped out symbols. */
6319 bfd_byte *symbuf;
6320 /* And one for symbol section indices. */
6321 Elf_External_Sym_Shndx *symshndxbuf;
6322 /* Number of swapped out symbols in buffer. */
6323 size_t symbuf_count;
6324 /* Number of symbols which fit in symbuf. */
6325 size_t symbuf_size;
6326 /* And same for symshndxbuf. */
6327 size_t shndxbuf_size;
6330 /* This struct is used to pass information to elf_link_output_extsym. */
6332 struct elf_outext_info
6334 bfd_boolean failed;
6335 bfd_boolean localsyms;
6336 struct elf_final_link_info *finfo;
6339 /* When performing a relocatable link, the input relocations are
6340 preserved. But, if they reference global symbols, the indices
6341 referenced must be updated. Update all the relocations in
6342 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
6344 static void
6345 elf_link_adjust_relocs (bfd *abfd,
6346 Elf_Internal_Shdr *rel_hdr,
6347 unsigned int count,
6348 struct elf_link_hash_entry **rel_hash)
6350 unsigned int i;
6351 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
6352 bfd_byte *erela;
6353 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
6354 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
6355 bfd_vma r_type_mask;
6356 int r_sym_shift;
6358 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
6360 swap_in = bed->s->swap_reloc_in;
6361 swap_out = bed->s->swap_reloc_out;
6363 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
6365 swap_in = bed->s->swap_reloca_in;
6366 swap_out = bed->s->swap_reloca_out;
6368 else
6369 abort ();
6371 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
6372 abort ();
6374 if (bed->s->arch_size == 32)
6376 r_type_mask = 0xff;
6377 r_sym_shift = 8;
6379 else
6381 r_type_mask = 0xffffffff;
6382 r_sym_shift = 32;
6385 erela = rel_hdr->contents;
6386 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
6388 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
6389 unsigned int j;
6391 if (*rel_hash == NULL)
6392 continue;
6394 BFD_ASSERT ((*rel_hash)->indx >= 0);
6396 (*swap_in) (abfd, erela, irela);
6397 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
6398 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
6399 | (irela[j].r_info & r_type_mask));
6400 (*swap_out) (abfd, irela, erela);
6404 struct elf_link_sort_rela
6406 union {
6407 bfd_vma offset;
6408 bfd_vma sym_mask;
6409 } u;
6410 enum elf_reloc_type_class type;
6411 /* We use this as an array of size int_rels_per_ext_rel. */
6412 Elf_Internal_Rela rela[1];
6415 static int
6416 elf_link_sort_cmp1 (const void *A, const void *B)
6418 const struct elf_link_sort_rela *a = A;
6419 const struct elf_link_sort_rela *b = B;
6420 int relativea, relativeb;
6422 relativea = a->type == reloc_class_relative;
6423 relativeb = b->type == reloc_class_relative;
6425 if (relativea < relativeb)
6426 return 1;
6427 if (relativea > relativeb)
6428 return -1;
6429 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
6430 return -1;
6431 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
6432 return 1;
6433 if (a->rela->r_offset < b->rela->r_offset)
6434 return -1;
6435 if (a->rela->r_offset > b->rela->r_offset)
6436 return 1;
6437 return 0;
6440 static int
6441 elf_link_sort_cmp2 (const void *A, const void *B)
6443 const struct elf_link_sort_rela *a = A;
6444 const struct elf_link_sort_rela *b = B;
6445 int copya, copyb;
6447 if (a->u.offset < b->u.offset)
6448 return -1;
6449 if (a->u.offset > b->u.offset)
6450 return 1;
6451 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
6452 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
6453 if (copya < copyb)
6454 return -1;
6455 if (copya > copyb)
6456 return 1;
6457 if (a->rela->r_offset < b->rela->r_offset)
6458 return -1;
6459 if (a->rela->r_offset > b->rela->r_offset)
6460 return 1;
6461 return 0;
6464 static size_t
6465 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
6467 asection *reldyn;
6468 bfd_size_type count, size;
6469 size_t i, ret, sort_elt, ext_size;
6470 bfd_byte *sort, *s_non_relative, *p;
6471 struct elf_link_sort_rela *sq;
6472 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
6473 int i2e = bed->s->int_rels_per_ext_rel;
6474 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
6475 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
6476 struct bfd_link_order *lo;
6477 bfd_vma r_sym_mask;
6479 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
6480 if (reldyn == NULL || reldyn->size == 0)
6482 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
6483 if (reldyn == NULL || reldyn->size == 0)
6484 return 0;
6485 ext_size = bed->s->sizeof_rel;
6486 swap_in = bed->s->swap_reloc_in;
6487 swap_out = bed->s->swap_reloc_out;
6489 else
6491 ext_size = bed->s->sizeof_rela;
6492 swap_in = bed->s->swap_reloca_in;
6493 swap_out = bed->s->swap_reloca_out;
6495 count = reldyn->size / ext_size;
6497 size = 0;
6498 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6499 if (lo->type == bfd_indirect_link_order)
6501 asection *o = lo->u.indirect.section;
6502 size += o->size;
6505 if (size != reldyn->size)
6506 return 0;
6508 sort_elt = (sizeof (struct elf_link_sort_rela)
6509 + (i2e - 1) * sizeof (Elf_Internal_Rela));
6510 sort = bfd_zmalloc (sort_elt * count);
6511 if (sort == NULL)
6513 (*info->callbacks->warning)
6514 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
6515 return 0;
6518 if (bed->s->arch_size == 32)
6519 r_sym_mask = ~(bfd_vma) 0xff;
6520 else
6521 r_sym_mask = ~(bfd_vma) 0xffffffff;
6523 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6524 if (lo->type == bfd_indirect_link_order)
6526 bfd_byte *erel, *erelend;
6527 asection *o = lo->u.indirect.section;
6529 if (o->contents == NULL && o->size != 0)
6531 /* This is a reloc section that is being handled as a normal
6532 section. See bfd_section_from_shdr. We can't combine
6533 relocs in this case. */
6534 free (sort);
6535 return 0;
6537 erel = o->contents;
6538 erelend = o->contents + o->size;
6539 p = sort + o->output_offset / ext_size * sort_elt;
6540 while (erel < erelend)
6542 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6543 (*swap_in) (abfd, erel, s->rela);
6544 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
6545 s->u.sym_mask = r_sym_mask;
6546 p += sort_elt;
6547 erel += ext_size;
6551 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
6553 for (i = 0, p = sort; i < count; i++, p += sort_elt)
6555 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6556 if (s->type != reloc_class_relative)
6557 break;
6559 ret = i;
6560 s_non_relative = p;
6562 sq = (struct elf_link_sort_rela *) s_non_relative;
6563 for (; i < count; i++, p += sort_elt)
6565 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
6566 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
6567 sq = sp;
6568 sp->u.offset = sq->rela->r_offset;
6571 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
6573 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6574 if (lo->type == bfd_indirect_link_order)
6576 bfd_byte *erel, *erelend;
6577 asection *o = lo->u.indirect.section;
6579 erel = o->contents;
6580 erelend = o->contents + o->size;
6581 p = sort + o->output_offset / ext_size * sort_elt;
6582 while (erel < erelend)
6584 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6585 (*swap_out) (abfd, s->rela, erel);
6586 p += sort_elt;
6587 erel += ext_size;
6591 free (sort);
6592 *psec = reldyn;
6593 return ret;
6596 /* Flush the output symbols to the file. */
6598 static bfd_boolean
6599 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
6600 const struct elf_backend_data *bed)
6602 if (finfo->symbuf_count > 0)
6604 Elf_Internal_Shdr *hdr;
6605 file_ptr pos;
6606 bfd_size_type amt;
6608 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6609 pos = hdr->sh_offset + hdr->sh_size;
6610 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6611 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6612 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6613 return FALSE;
6615 hdr->sh_size += amt;
6616 finfo->symbuf_count = 0;
6619 return TRUE;
6622 /* Add a symbol to the output symbol table. */
6624 static bfd_boolean
6625 elf_link_output_sym (struct elf_final_link_info *finfo,
6626 const char *name,
6627 Elf_Internal_Sym *elfsym,
6628 asection *input_sec,
6629 struct elf_link_hash_entry *h)
6631 bfd_byte *dest;
6632 Elf_External_Sym_Shndx *destshndx;
6633 bfd_boolean (*output_symbol_hook)
6634 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6635 struct elf_link_hash_entry *);
6636 const struct elf_backend_data *bed;
6638 bed = get_elf_backend_data (finfo->output_bfd);
6639 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6640 if (output_symbol_hook != NULL)
6642 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6643 return FALSE;
6646 if (name == NULL || *name == '\0')
6647 elfsym->st_name = 0;
6648 else if (input_sec->flags & SEC_EXCLUDE)
6649 elfsym->st_name = 0;
6650 else
6652 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6653 name, TRUE, FALSE);
6654 if (elfsym->st_name == (unsigned long) -1)
6655 return FALSE;
6658 if (finfo->symbuf_count >= finfo->symbuf_size)
6660 if (! elf_link_flush_output_syms (finfo, bed))
6661 return FALSE;
6664 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6665 destshndx = finfo->symshndxbuf;
6666 if (destshndx != NULL)
6668 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6670 bfd_size_type amt;
6672 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6673 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6674 if (destshndx == NULL)
6675 return FALSE;
6676 memset ((char *) destshndx + amt, 0, amt);
6677 finfo->shndxbuf_size *= 2;
6679 destshndx += bfd_get_symcount (finfo->output_bfd);
6682 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6683 finfo->symbuf_count += 1;
6684 bfd_get_symcount (finfo->output_bfd) += 1;
6686 return TRUE;
6689 /* Return TRUE if the dynamic symbol SYM in ABFD is supported. */
6691 static bfd_boolean
6692 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
6694 if (sym->st_shndx > SHN_HIRESERVE)
6696 /* The gABI doesn't support dynamic symbols in output sections
6697 beyond 64k. */
6698 (*_bfd_error_handler)
6699 (_("%B: Too many sections: %d (>= %d)"),
6700 abfd, bfd_count_sections (abfd), SHN_LORESERVE);
6701 bfd_set_error (bfd_error_nonrepresentable_section);
6702 return FALSE;
6704 return TRUE;
6707 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6708 allowing an unsatisfied unversioned symbol in the DSO to match a
6709 versioned symbol that would normally require an explicit version.
6710 We also handle the case that a DSO references a hidden symbol
6711 which may be satisfied by a versioned symbol in another DSO. */
6713 static bfd_boolean
6714 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6715 const struct elf_backend_data *bed,
6716 struct elf_link_hash_entry *h)
6718 bfd *abfd;
6719 struct elf_link_loaded_list *loaded;
6721 if (!is_elf_hash_table (info->hash))
6722 return FALSE;
6724 switch (h->root.type)
6726 default:
6727 abfd = NULL;
6728 break;
6730 case bfd_link_hash_undefined:
6731 case bfd_link_hash_undefweak:
6732 abfd = h->root.u.undef.abfd;
6733 if ((abfd->flags & DYNAMIC) == 0
6734 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6735 return FALSE;
6736 break;
6738 case bfd_link_hash_defined:
6739 case bfd_link_hash_defweak:
6740 abfd = h->root.u.def.section->owner;
6741 break;
6743 case bfd_link_hash_common:
6744 abfd = h->root.u.c.p->section->owner;
6745 break;
6747 BFD_ASSERT (abfd != NULL);
6749 for (loaded = elf_hash_table (info)->loaded;
6750 loaded != NULL;
6751 loaded = loaded->next)
6753 bfd *input;
6754 Elf_Internal_Shdr *hdr;
6755 bfd_size_type symcount;
6756 bfd_size_type extsymcount;
6757 bfd_size_type extsymoff;
6758 Elf_Internal_Shdr *versymhdr;
6759 Elf_Internal_Sym *isym;
6760 Elf_Internal_Sym *isymend;
6761 Elf_Internal_Sym *isymbuf;
6762 Elf_External_Versym *ever;
6763 Elf_External_Versym *extversym;
6765 input = loaded->abfd;
6767 /* We check each DSO for a possible hidden versioned definition. */
6768 if (input == abfd
6769 || (input->flags & DYNAMIC) == 0
6770 || elf_dynversym (input) == 0)
6771 continue;
6773 hdr = &elf_tdata (input)->dynsymtab_hdr;
6775 symcount = hdr->sh_size / bed->s->sizeof_sym;
6776 if (elf_bad_symtab (input))
6778 extsymcount = symcount;
6779 extsymoff = 0;
6781 else
6783 extsymcount = symcount - hdr->sh_info;
6784 extsymoff = hdr->sh_info;
6787 if (extsymcount == 0)
6788 continue;
6790 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6791 NULL, NULL, NULL);
6792 if (isymbuf == NULL)
6793 return FALSE;
6795 /* Read in any version definitions. */
6796 versymhdr = &elf_tdata (input)->dynversym_hdr;
6797 extversym = bfd_malloc (versymhdr->sh_size);
6798 if (extversym == NULL)
6799 goto error_ret;
6801 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6802 || (bfd_bread (extversym, versymhdr->sh_size, input)
6803 != versymhdr->sh_size))
6805 free (extversym);
6806 error_ret:
6807 free (isymbuf);
6808 return FALSE;
6811 ever = extversym + extsymoff;
6812 isymend = isymbuf + extsymcount;
6813 for (isym = isymbuf; isym < isymend; isym++, ever++)
6815 const char *name;
6816 Elf_Internal_Versym iver;
6817 unsigned short version_index;
6819 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6820 || isym->st_shndx == SHN_UNDEF)
6821 continue;
6823 name = bfd_elf_string_from_elf_section (input,
6824 hdr->sh_link,
6825 isym->st_name);
6826 if (strcmp (name, h->root.root.string) != 0)
6827 continue;
6829 _bfd_elf_swap_versym_in (input, ever, &iver);
6831 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6833 /* If we have a non-hidden versioned sym, then it should
6834 have provided a definition for the undefined sym. */
6835 abort ();
6838 version_index = iver.vs_vers & VERSYM_VERSION;
6839 if (version_index == 1 || version_index == 2)
6841 /* This is the base or first version. We can use it. */
6842 free (extversym);
6843 free (isymbuf);
6844 return TRUE;
6848 free (extversym);
6849 free (isymbuf);
6852 return FALSE;
6855 /* Add an external symbol to the symbol table. This is called from
6856 the hash table traversal routine. When generating a shared object,
6857 we go through the symbol table twice. The first time we output
6858 anything that might have been forced to local scope in a version
6859 script. The second time we output the symbols that are still
6860 global symbols. */
6862 static bfd_boolean
6863 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6865 struct elf_outext_info *eoinfo = data;
6866 struct elf_final_link_info *finfo = eoinfo->finfo;
6867 bfd_boolean strip;
6868 Elf_Internal_Sym sym;
6869 asection *input_sec;
6870 const struct elf_backend_data *bed;
6872 if (h->root.type == bfd_link_hash_warning)
6874 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6875 if (h->root.type == bfd_link_hash_new)
6876 return TRUE;
6879 /* Decide whether to output this symbol in this pass. */
6880 if (eoinfo->localsyms)
6882 if (!h->forced_local)
6883 return TRUE;
6885 else
6887 if (h->forced_local)
6888 return TRUE;
6891 bed = get_elf_backend_data (finfo->output_bfd);
6893 if (h->root.type == bfd_link_hash_undefined)
6895 /* If we have an undefined symbol reference here then it must have
6896 come from a shared library that is being linked in. (Undefined
6897 references in regular files have already been handled). */
6898 bfd_boolean ignore_undef = FALSE;
6900 /* Some symbols may be special in that the fact that they're
6901 undefined can be safely ignored - let backend determine that. */
6902 if (bed->elf_backend_ignore_undef_symbol)
6903 ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
6905 /* If we are reporting errors for this situation then do so now. */
6906 if (ignore_undef == FALSE
6907 && h->ref_dynamic
6908 && ! h->ref_regular
6909 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6910 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6912 if (! (finfo->info->callbacks->undefined_symbol
6913 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6914 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6916 eoinfo->failed = TRUE;
6917 return FALSE;
6922 /* We should also warn if a forced local symbol is referenced from
6923 shared libraries. */
6924 if (! finfo->info->relocatable
6925 && (! finfo->info->shared)
6926 && h->forced_local
6927 && h->ref_dynamic
6928 && !h->dynamic_def
6929 && !h->dynamic_weak
6930 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6932 (*_bfd_error_handler)
6933 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6934 finfo->output_bfd,
6935 h->root.u.def.section == bfd_abs_section_ptr
6936 ? finfo->output_bfd : h->root.u.def.section->owner,
6937 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6938 ? "internal"
6939 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6940 ? "hidden" : "local",
6941 h->root.root.string);
6942 eoinfo->failed = TRUE;
6943 return FALSE;
6946 /* We don't want to output symbols that have never been mentioned by
6947 a regular file, or that we have been told to strip. However, if
6948 h->indx is set to -2, the symbol is used by a reloc and we must
6949 output it. */
6950 if (h->indx == -2)
6951 strip = FALSE;
6952 else if ((h->def_dynamic
6953 || h->ref_dynamic
6954 || h->root.type == bfd_link_hash_new)
6955 && !h->def_regular
6956 && !h->ref_regular)
6957 strip = TRUE;
6958 else if (finfo->info->strip == strip_all)
6959 strip = TRUE;
6960 else if (finfo->info->strip == strip_some
6961 && bfd_hash_lookup (finfo->info->keep_hash,
6962 h->root.root.string, FALSE, FALSE) == NULL)
6963 strip = TRUE;
6964 else if (finfo->info->strip_discarded
6965 && (h->root.type == bfd_link_hash_defined
6966 || h->root.type == bfd_link_hash_defweak)
6967 && elf_discarded_section (h->root.u.def.section))
6968 strip = TRUE;
6969 else
6970 strip = FALSE;
6972 /* If we're stripping it, and it's not a dynamic symbol, there's
6973 nothing else to do unless it is a forced local symbol. */
6974 if (strip
6975 && h->dynindx == -1
6976 && !h->forced_local)
6977 return TRUE;
6979 sym.st_value = 0;
6980 sym.st_size = h->size;
6981 sym.st_other = h->other;
6982 if (h->forced_local)
6983 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6984 else if (h->root.type == bfd_link_hash_undefweak
6985 || h->root.type == bfd_link_hash_defweak)
6986 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6987 else
6988 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6990 switch (h->root.type)
6992 default:
6993 case bfd_link_hash_new:
6994 case bfd_link_hash_warning:
6995 abort ();
6996 return FALSE;
6998 case bfd_link_hash_undefined:
6999 case bfd_link_hash_undefweak:
7000 input_sec = bfd_und_section_ptr;
7001 sym.st_shndx = SHN_UNDEF;
7002 break;
7004 case bfd_link_hash_defined:
7005 case bfd_link_hash_defweak:
7007 input_sec = h->root.u.def.section;
7008 if (input_sec->output_section != NULL)
7010 sym.st_shndx =
7011 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
7012 input_sec->output_section);
7013 if (sym.st_shndx == SHN_BAD)
7015 (*_bfd_error_handler)
7016 (_("%B: could not find output section %A for input section %A"),
7017 finfo->output_bfd, input_sec->output_section, input_sec);
7018 eoinfo->failed = TRUE;
7019 return FALSE;
7022 /* ELF symbols in relocatable files are section relative,
7023 but in nonrelocatable files they are virtual
7024 addresses. */
7025 sym.st_value = h->root.u.def.value + input_sec->output_offset;
7026 if (! finfo->info->relocatable)
7028 sym.st_value += input_sec->output_section->vma;
7029 if (h->type == STT_TLS)
7031 /* STT_TLS symbols are relative to PT_TLS segment
7032 base. */
7033 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
7034 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
7038 else
7040 BFD_ASSERT (input_sec->owner == NULL
7041 || (input_sec->owner->flags & DYNAMIC) != 0);
7042 sym.st_shndx = SHN_UNDEF;
7043 input_sec = bfd_und_section_ptr;
7046 break;
7048 case bfd_link_hash_common:
7049 input_sec = h->root.u.c.p->section;
7050 sym.st_shndx = bed->common_section_index (input_sec);
7051 sym.st_value = 1 << h->root.u.c.p->alignment_power;
7052 break;
7054 case bfd_link_hash_indirect:
7055 /* These symbols are created by symbol versioning. They point
7056 to the decorated version of the name. For example, if the
7057 symbol foo@@GNU_1.2 is the default, which should be used when
7058 foo is used with no version, then we add an indirect symbol
7059 foo which points to foo@@GNU_1.2. We ignore these symbols,
7060 since the indirected symbol is already in the hash table. */
7061 return TRUE;
7064 /* Give the processor backend a chance to tweak the symbol value,
7065 and also to finish up anything that needs to be done for this
7066 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
7067 forced local syms when non-shared is due to a historical quirk. */
7068 if ((h->dynindx != -1
7069 || h->forced_local)
7070 && ((finfo->info->shared
7071 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
7072 || h->root.type != bfd_link_hash_undefweak))
7073 || !h->forced_local)
7074 && elf_hash_table (finfo->info)->dynamic_sections_created)
7076 if (! ((*bed->elf_backend_finish_dynamic_symbol)
7077 (finfo->output_bfd, finfo->info, h, &sym)))
7079 eoinfo->failed = TRUE;
7080 return FALSE;
7084 /* If we are marking the symbol as undefined, and there are no
7085 non-weak references to this symbol from a regular object, then
7086 mark the symbol as weak undefined; if there are non-weak
7087 references, mark the symbol as strong. We can't do this earlier,
7088 because it might not be marked as undefined until the
7089 finish_dynamic_symbol routine gets through with it. */
7090 if (sym.st_shndx == SHN_UNDEF
7091 && h->ref_regular
7092 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
7093 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
7095 int bindtype;
7097 if (h->ref_regular_nonweak)
7098 bindtype = STB_GLOBAL;
7099 else
7100 bindtype = STB_WEAK;
7101 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
7104 /* If a non-weak symbol with non-default visibility is not defined
7105 locally, it is a fatal error. */
7106 if (! finfo->info->relocatable
7107 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
7108 && ELF_ST_BIND (sym.st_info) != STB_WEAK
7109 && h->root.type == bfd_link_hash_undefined
7110 && !h->def_regular)
7112 (*_bfd_error_handler)
7113 (_("%B: %s symbol `%s' isn't defined"),
7114 finfo->output_bfd,
7115 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
7116 ? "protected"
7117 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
7118 ? "internal" : "hidden",
7119 h->root.root.string);
7120 eoinfo->failed = TRUE;
7121 return FALSE;
7124 /* If this symbol should be put in the .dynsym section, then put it
7125 there now. We already know the symbol index. We also fill in
7126 the entry in the .hash section. */
7127 if (h->dynindx != -1
7128 && elf_hash_table (finfo->info)->dynamic_sections_created)
7130 bfd_byte *esym;
7132 sym.st_name = h->dynstr_index;
7133 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
7134 if (! check_dynsym (finfo->output_bfd, &sym))
7136 eoinfo->failed = TRUE;
7137 return FALSE;
7139 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
7141 if (finfo->hash_sec != NULL)
7143 size_t hash_entry_size;
7144 bfd_byte *bucketpos;
7145 bfd_vma chain;
7146 size_t bucketcount;
7147 size_t bucket;
7149 bucketcount = elf_hash_table (finfo->info)->bucketcount;
7150 bucket = h->u.elf_hash_value % bucketcount;
7152 hash_entry_size
7153 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
7154 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
7155 + (bucket + 2) * hash_entry_size);
7156 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
7157 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
7158 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
7159 ((bfd_byte *) finfo->hash_sec->contents
7160 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
7163 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
7165 Elf_Internal_Versym iversym;
7166 Elf_External_Versym *eversym;
7168 if (!h->def_regular)
7170 if (h->verinfo.verdef == NULL)
7171 iversym.vs_vers = 0;
7172 else
7173 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
7175 else
7177 if (h->verinfo.vertree == NULL)
7178 iversym.vs_vers = 1;
7179 else
7180 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
7181 if (finfo->info->create_default_symver)
7182 iversym.vs_vers++;
7185 if (h->hidden)
7186 iversym.vs_vers |= VERSYM_HIDDEN;
7188 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
7189 eversym += h->dynindx;
7190 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
7194 /* If we're stripping it, then it was just a dynamic symbol, and
7195 there's nothing else to do. */
7196 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
7197 return TRUE;
7199 h->indx = bfd_get_symcount (finfo->output_bfd);
7201 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
7203 eoinfo->failed = TRUE;
7204 return FALSE;
7207 return TRUE;
7210 /* Return TRUE if special handling is done for relocs in SEC against
7211 symbols defined in discarded sections. */
7213 static bfd_boolean
7214 elf_section_ignore_discarded_relocs (asection *sec)
7216 const struct elf_backend_data *bed;
7218 switch (sec->sec_info_type)
7220 case ELF_INFO_TYPE_STABS:
7221 case ELF_INFO_TYPE_EH_FRAME:
7222 return TRUE;
7223 default:
7224 break;
7227 bed = get_elf_backend_data (sec->owner);
7228 if (bed->elf_backend_ignore_discarded_relocs != NULL
7229 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
7230 return TRUE;
7232 return FALSE;
7235 /* Return a mask saying how ld should treat relocations in SEC against
7236 symbols defined in discarded sections. If this function returns
7237 COMPLAIN set, ld will issue a warning message. If this function
7238 returns PRETEND set, and the discarded section was link-once and the
7239 same size as the kept link-once section, ld will pretend that the
7240 symbol was actually defined in the kept section. Otherwise ld will
7241 zero the reloc (at least that is the intent, but some cooperation by
7242 the target dependent code is needed, particularly for REL targets). */
7244 unsigned int
7245 _bfd_elf_default_action_discarded (asection *sec)
7247 if (sec->flags & SEC_DEBUGGING)
7248 return PRETEND;
7250 if (strcmp (".eh_frame", sec->name) == 0)
7251 return 0;
7253 if (strcmp (".gcc_except_table", sec->name) == 0)
7254 return 0;
7256 return COMPLAIN | PRETEND;
7259 /* Find a match between a section and a member of a section group. */
7261 static asection *
7262 match_group_member (asection *sec, asection *group,
7263 struct bfd_link_info *info)
7265 asection *first = elf_next_in_group (group);
7266 asection *s = first;
7268 while (s != NULL)
7270 if (bfd_elf_match_symbols_in_sections (s, sec, info))
7271 return s;
7273 s = elf_next_in_group (s);
7274 if (s == first)
7275 break;
7278 return NULL;
7281 /* Check if the kept section of a discarded section SEC can be used
7282 to replace it. Return the replacement if it is OK. Otherwise return
7283 NULL. */
7285 asection *
7286 _bfd_elf_check_kept_section (asection *sec, struct bfd_link_info *info)
7288 asection *kept;
7290 kept = sec->kept_section;
7291 if (kept != NULL)
7293 if ((kept->flags & SEC_GROUP) != 0)
7294 kept = match_group_member (sec, kept, info);
7295 if (kept != NULL && sec->size != kept->size)
7296 kept = NULL;
7297 sec->kept_section = kept;
7299 return kept;
7302 /* Link an input file into the linker output file. This function
7303 handles all the sections and relocations of the input file at once.
7304 This is so that we only have to read the local symbols once, and
7305 don't have to keep them in memory. */
7307 static bfd_boolean
7308 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
7310 bfd_boolean (*relocate_section)
7311 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
7312 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
7313 bfd *output_bfd;
7314 Elf_Internal_Shdr *symtab_hdr;
7315 size_t locsymcount;
7316 size_t extsymoff;
7317 Elf_Internal_Sym *isymbuf;
7318 Elf_Internal_Sym *isym;
7319 Elf_Internal_Sym *isymend;
7320 long *pindex;
7321 asection **ppsection;
7322 asection *o;
7323 const struct elf_backend_data *bed;
7324 bfd_boolean emit_relocs;
7325 struct elf_link_hash_entry **sym_hashes;
7327 output_bfd = finfo->output_bfd;
7328 bed = get_elf_backend_data (output_bfd);
7329 relocate_section = bed->elf_backend_relocate_section;
7331 /* If this is a dynamic object, we don't want to do anything here:
7332 we don't want the local symbols, and we don't want the section
7333 contents. */
7334 if ((input_bfd->flags & DYNAMIC) != 0)
7335 return TRUE;
7337 emit_relocs = (finfo->info->relocatable
7338 || finfo->info->emitrelocations);
7340 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
7341 if (elf_bad_symtab (input_bfd))
7343 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
7344 extsymoff = 0;
7346 else
7348 locsymcount = symtab_hdr->sh_info;
7349 extsymoff = symtab_hdr->sh_info;
7352 /* Read the local symbols. */
7353 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
7354 if (isymbuf == NULL && locsymcount != 0)
7356 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
7357 finfo->internal_syms,
7358 finfo->external_syms,
7359 finfo->locsym_shndx);
7360 if (isymbuf == NULL)
7361 return FALSE;
7364 /* Find local symbol sections and adjust values of symbols in
7365 SEC_MERGE sections. Write out those local symbols we know are
7366 going into the output file. */
7367 isymend = isymbuf + locsymcount;
7368 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
7369 isym < isymend;
7370 isym++, pindex++, ppsection++)
7372 asection *isec;
7373 const char *name;
7374 Elf_Internal_Sym osym;
7376 *pindex = -1;
7378 if (elf_bad_symtab (input_bfd))
7380 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
7382 *ppsection = NULL;
7383 continue;
7387 if (isym->st_shndx == SHN_UNDEF)
7388 isec = bfd_und_section_ptr;
7389 else if (isym->st_shndx < SHN_LORESERVE
7390 || isym->st_shndx > SHN_HIRESERVE)
7392 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
7393 if (isec
7394 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
7395 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
7396 isym->st_value =
7397 _bfd_merged_section_offset (output_bfd, &isec,
7398 elf_section_data (isec)->sec_info,
7399 isym->st_value);
7401 else if (isym->st_shndx == SHN_ABS)
7402 isec = bfd_abs_section_ptr;
7403 else if (isym->st_shndx == SHN_COMMON)
7404 isec = bfd_com_section_ptr;
7405 else
7407 /* Don't attempt to output symbols with st_shnx in the
7408 reserved range other than SHN_ABS and SHN_COMMON. */
7409 *ppsection = NULL;
7410 continue;
7413 *ppsection = isec;
7415 /* Don't output the first, undefined, symbol. */
7416 if (ppsection == finfo->sections)
7417 continue;
7419 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
7421 /* We never output section symbols. Instead, we use the
7422 section symbol of the corresponding section in the output
7423 file. */
7424 continue;
7427 /* If we are stripping all symbols, we don't want to output this
7428 one. */
7429 if (finfo->info->strip == strip_all)
7430 continue;
7432 /* If we are discarding all local symbols, we don't want to
7433 output this one. If we are generating a relocatable output
7434 file, then some of the local symbols may be required by
7435 relocs; we output them below as we discover that they are
7436 needed. */
7437 if (finfo->info->discard == discard_all)
7438 continue;
7440 /* If this symbol is defined in a section which we are
7441 discarding, we don't need to keep it. */
7442 if (isym->st_shndx != SHN_UNDEF
7443 && (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
7444 && (isec == NULL
7445 || bfd_section_removed_from_list (output_bfd,
7446 isec->output_section)))
7447 continue;
7449 /* Get the name of the symbol. */
7450 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
7451 isym->st_name);
7452 if (name == NULL)
7453 return FALSE;
7455 /* See if we are discarding symbols with this name. */
7456 if ((finfo->info->strip == strip_some
7457 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
7458 == NULL))
7459 || (((finfo->info->discard == discard_sec_merge
7460 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
7461 || finfo->info->discard == discard_l)
7462 && bfd_is_local_label_name (input_bfd, name)))
7463 continue;
7465 /* If we get here, we are going to output this symbol. */
7467 osym = *isym;
7469 /* Adjust the section index for the output file. */
7470 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
7471 isec->output_section);
7472 if (osym.st_shndx == SHN_BAD)
7473 return FALSE;
7475 *pindex = bfd_get_symcount (output_bfd);
7477 /* ELF symbols in relocatable files are section relative, but
7478 in executable files they are virtual addresses. Note that
7479 this code assumes that all ELF sections have an associated
7480 BFD section with a reasonable value for output_offset; below
7481 we assume that they also have a reasonable value for
7482 output_section. Any special sections must be set up to meet
7483 these requirements. */
7484 osym.st_value += isec->output_offset;
7485 if (! finfo->info->relocatable)
7487 osym.st_value += isec->output_section->vma;
7488 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
7490 /* STT_TLS symbols are relative to PT_TLS segment base. */
7491 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
7492 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
7496 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
7497 return FALSE;
7500 /* Relocate the contents of each section. */
7501 sym_hashes = elf_sym_hashes (input_bfd);
7502 for (o = input_bfd->sections; o != NULL; o = o->next)
7504 bfd_byte *contents;
7506 if (! o->linker_mark)
7508 /* This section was omitted from the link. */
7509 continue;
7512 if ((o->flags & SEC_HAS_CONTENTS) == 0
7513 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
7514 continue;
7516 if ((o->flags & SEC_LINKER_CREATED) != 0)
7518 /* Section was created by _bfd_elf_link_create_dynamic_sections
7519 or somesuch. */
7520 continue;
7523 /* Get the contents of the section. They have been cached by a
7524 relaxation routine. Note that o is a section in an input
7525 file, so the contents field will not have been set by any of
7526 the routines which work on output files. */
7527 if (elf_section_data (o)->this_hdr.contents != NULL)
7528 contents = elf_section_data (o)->this_hdr.contents;
7529 else
7531 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
7533 contents = finfo->contents;
7534 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
7535 return FALSE;
7538 if ((o->flags & SEC_RELOC) != 0)
7540 Elf_Internal_Rela *internal_relocs;
7541 bfd_vma r_type_mask;
7542 int r_sym_shift;
7544 /* Get the swapped relocs. */
7545 internal_relocs
7546 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
7547 finfo->internal_relocs, FALSE);
7548 if (internal_relocs == NULL
7549 && o->reloc_count > 0)
7550 return FALSE;
7552 if (bed->s->arch_size == 32)
7554 r_type_mask = 0xff;
7555 r_sym_shift = 8;
7557 else
7559 r_type_mask = 0xffffffff;
7560 r_sym_shift = 32;
7563 /* Run through the relocs looking for any against symbols
7564 from discarded sections and section symbols from
7565 removed link-once sections. Complain about relocs
7566 against discarded sections. Zero relocs against removed
7567 link-once sections. */
7568 if (!elf_section_ignore_discarded_relocs (o))
7570 Elf_Internal_Rela *rel, *relend;
7571 unsigned int action = (*bed->action_discarded) (o);
7573 rel = internal_relocs;
7574 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
7575 for ( ; rel < relend; rel++)
7577 unsigned long r_symndx = rel->r_info >> r_sym_shift;
7578 asection **ps, *sec;
7579 struct elf_link_hash_entry *h = NULL;
7580 const char *sym_name;
7582 if (r_symndx == STN_UNDEF)
7583 continue;
7585 if (r_symndx >= locsymcount
7586 || (elf_bad_symtab (input_bfd)
7587 && finfo->sections[r_symndx] == NULL))
7589 h = sym_hashes[r_symndx - extsymoff];
7591 /* Badly formatted input files can contain relocs that
7592 reference non-existant symbols. Check here so that
7593 we do not seg fault. */
7594 if (h == NULL)
7596 char buffer [32];
7598 sprintf_vma (buffer, rel->r_info);
7599 (*_bfd_error_handler)
7600 (_("error: %B contains a reloc (0x%s) for section %A "
7601 "that references a non-existent global symbol"),
7602 input_bfd, o, buffer);
7603 bfd_set_error (bfd_error_bad_value);
7604 return FALSE;
7607 while (h->root.type == bfd_link_hash_indirect
7608 || h->root.type == bfd_link_hash_warning)
7609 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7611 if (h->root.type != bfd_link_hash_defined
7612 && h->root.type != bfd_link_hash_defweak)
7613 continue;
7615 ps = &h->root.u.def.section;
7616 sym_name = h->root.root.string;
7618 else
7620 Elf_Internal_Sym *sym = isymbuf + r_symndx;
7621 ps = &finfo->sections[r_symndx];
7622 sym_name = bfd_elf_sym_name (input_bfd,
7623 symtab_hdr,
7624 sym, *ps);
7627 /* Complain if the definition comes from a
7628 discarded section. */
7629 if ((sec = *ps) != NULL && elf_discarded_section (sec))
7631 BFD_ASSERT (r_symndx != 0);
7632 if (action & COMPLAIN)
7633 (*finfo->info->callbacks->einfo)
7634 (_("%X`%s' referenced in section `%A' of %B: "
7635 "defined in discarded section `%A' of %B\n"),
7636 sym_name, o, input_bfd, sec, sec->owner);
7638 /* Try to do the best we can to support buggy old
7639 versions of gcc. Pretend that the symbol is
7640 really defined in the kept linkonce section.
7641 FIXME: This is quite broken. Modifying the
7642 symbol here means we will be changing all later
7643 uses of the symbol, not just in this section. */
7644 if (action & PRETEND)
7646 asection *kept;
7648 kept = _bfd_elf_check_kept_section (sec,
7649 finfo->info);
7650 if (kept != NULL)
7652 *ps = kept;
7653 continue;
7657 /* Remove the symbol reference from the reloc, but
7658 don't kill the reloc completely. This is so that
7659 a zero value will be written into the section,
7660 which may have non-zero contents put there by the
7661 assembler. Zero in things like an eh_frame fde
7662 pc_begin allows stack unwinders to recognize the
7663 fde as bogus. */
7664 rel->r_info &= r_type_mask;
7665 rel->r_addend = 0;
7670 /* Relocate the section by invoking a back end routine.
7672 The back end routine is responsible for adjusting the
7673 section contents as necessary, and (if using Rela relocs
7674 and generating a relocatable output file) adjusting the
7675 reloc addend as necessary.
7677 The back end routine does not have to worry about setting
7678 the reloc address or the reloc symbol index.
7680 The back end routine is given a pointer to the swapped in
7681 internal symbols, and can access the hash table entries
7682 for the external symbols via elf_sym_hashes (input_bfd).
7684 When generating relocatable output, the back end routine
7685 must handle STB_LOCAL/STT_SECTION symbols specially. The
7686 output symbol is going to be a section symbol
7687 corresponding to the output section, which will require
7688 the addend to be adjusted. */
7690 if (! (*relocate_section) (output_bfd, finfo->info,
7691 input_bfd, o, contents,
7692 internal_relocs,
7693 isymbuf,
7694 finfo->sections))
7695 return FALSE;
7697 if (emit_relocs)
7699 Elf_Internal_Rela *irela;
7700 Elf_Internal_Rela *irelaend;
7701 bfd_vma last_offset;
7702 struct elf_link_hash_entry **rel_hash;
7703 struct elf_link_hash_entry **rel_hash_list;
7704 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7705 unsigned int next_erel;
7706 bfd_boolean rela_normal;
7708 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7709 rela_normal = (bed->rela_normal
7710 && (input_rel_hdr->sh_entsize
7711 == bed->s->sizeof_rela));
7713 /* Adjust the reloc addresses and symbol indices. */
7715 irela = internal_relocs;
7716 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7717 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7718 + elf_section_data (o->output_section)->rel_count
7719 + elf_section_data (o->output_section)->rel_count2);
7720 rel_hash_list = rel_hash;
7721 last_offset = o->output_offset;
7722 if (!finfo->info->relocatable)
7723 last_offset += o->output_section->vma;
7724 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7726 unsigned long r_symndx;
7727 asection *sec;
7728 Elf_Internal_Sym sym;
7730 if (next_erel == bed->s->int_rels_per_ext_rel)
7732 rel_hash++;
7733 next_erel = 0;
7736 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7737 finfo->info, o,
7738 irela->r_offset);
7739 if (irela->r_offset >= (bfd_vma) -2)
7741 /* This is a reloc for a deleted entry or somesuch.
7742 Turn it into an R_*_NONE reloc, at the same
7743 offset as the last reloc. elf_eh_frame.c and
7744 bfd_elf_discard_info rely on reloc offsets
7745 being ordered. */
7746 irela->r_offset = last_offset;
7747 irela->r_info = 0;
7748 irela->r_addend = 0;
7749 continue;
7752 irela->r_offset += o->output_offset;
7754 /* Relocs in an executable have to be virtual addresses. */
7755 if (!finfo->info->relocatable)
7756 irela->r_offset += o->output_section->vma;
7758 last_offset = irela->r_offset;
7760 r_symndx = irela->r_info >> r_sym_shift;
7761 if (r_symndx == STN_UNDEF)
7762 continue;
7764 if (r_symndx >= locsymcount
7765 || (elf_bad_symtab (input_bfd)
7766 && finfo->sections[r_symndx] == NULL))
7768 struct elf_link_hash_entry *rh;
7769 unsigned long indx;
7771 /* This is a reloc against a global symbol. We
7772 have not yet output all the local symbols, so
7773 we do not know the symbol index of any global
7774 symbol. We set the rel_hash entry for this
7775 reloc to point to the global hash table entry
7776 for this symbol. The symbol index is then
7777 set at the end of bfd_elf_final_link. */
7778 indx = r_symndx - extsymoff;
7779 rh = elf_sym_hashes (input_bfd)[indx];
7780 while (rh->root.type == bfd_link_hash_indirect
7781 || rh->root.type == bfd_link_hash_warning)
7782 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7784 /* Setting the index to -2 tells
7785 elf_link_output_extsym that this symbol is
7786 used by a reloc. */
7787 BFD_ASSERT (rh->indx < 0);
7788 rh->indx = -2;
7790 *rel_hash = rh;
7792 continue;
7795 /* This is a reloc against a local symbol. */
7797 *rel_hash = NULL;
7798 sym = isymbuf[r_symndx];
7799 sec = finfo->sections[r_symndx];
7800 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7802 /* I suppose the backend ought to fill in the
7803 section of any STT_SECTION symbol against a
7804 processor specific section. */
7805 r_symndx = 0;
7806 if (bfd_is_abs_section (sec))
7808 else if (sec == NULL || sec->owner == NULL)
7810 bfd_set_error (bfd_error_bad_value);
7811 return FALSE;
7813 else
7815 asection *osec = sec->output_section;
7817 /* If we have discarded a section, the output
7818 section will be the absolute section. In
7819 case of discarded link-once and discarded
7820 SEC_MERGE sections, use the kept section. */
7821 if (bfd_is_abs_section (osec)
7822 && sec->kept_section != NULL
7823 && sec->kept_section->output_section != NULL)
7825 osec = sec->kept_section->output_section;
7826 irela->r_addend -= osec->vma;
7829 if (!bfd_is_abs_section (osec))
7831 r_symndx = osec->target_index;
7832 if (r_symndx == 0)
7834 struct elf_link_hash_table *htab;
7835 asection *oi;
7837 htab = elf_hash_table (finfo->info);
7838 oi = htab->text_index_section;
7839 if ((osec->flags & SEC_READONLY) == 0
7840 && htab->data_index_section != NULL)
7841 oi = htab->data_index_section;
7843 if (oi != NULL)
7845 irela->r_addend += osec->vma - oi->vma;
7846 r_symndx = oi->target_index;
7850 BFD_ASSERT (r_symndx != 0);
7854 /* Adjust the addend according to where the
7855 section winds up in the output section. */
7856 if (rela_normal)
7857 irela->r_addend += sec->output_offset;
7859 else
7861 if (finfo->indices[r_symndx] == -1)
7863 unsigned long shlink;
7864 const char *name;
7865 asection *osec;
7867 if (finfo->info->strip == strip_all)
7869 /* You can't do ld -r -s. */
7870 bfd_set_error (bfd_error_invalid_operation);
7871 return FALSE;
7874 /* This symbol was skipped earlier, but
7875 since it is needed by a reloc, we
7876 must output it now. */
7877 shlink = symtab_hdr->sh_link;
7878 name = (bfd_elf_string_from_elf_section
7879 (input_bfd, shlink, sym.st_name));
7880 if (name == NULL)
7881 return FALSE;
7883 osec = sec->output_section;
7884 sym.st_shndx =
7885 _bfd_elf_section_from_bfd_section (output_bfd,
7886 osec);
7887 if (sym.st_shndx == SHN_BAD)
7888 return FALSE;
7890 sym.st_value += sec->output_offset;
7891 if (! finfo->info->relocatable)
7893 sym.st_value += osec->vma;
7894 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7896 /* STT_TLS symbols are relative to PT_TLS
7897 segment base. */
7898 BFD_ASSERT (elf_hash_table (finfo->info)
7899 ->tls_sec != NULL);
7900 sym.st_value -= (elf_hash_table (finfo->info)
7901 ->tls_sec->vma);
7905 finfo->indices[r_symndx]
7906 = bfd_get_symcount (output_bfd);
7908 if (! elf_link_output_sym (finfo, name, &sym, sec,
7909 NULL))
7910 return FALSE;
7913 r_symndx = finfo->indices[r_symndx];
7916 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7917 | (irela->r_info & r_type_mask));
7920 /* Swap out the relocs. */
7921 if (input_rel_hdr->sh_size != 0
7922 && !bed->elf_backend_emit_relocs (output_bfd, o,
7923 input_rel_hdr,
7924 internal_relocs,
7925 rel_hash_list))
7926 return FALSE;
7928 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7929 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7931 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7932 * bed->s->int_rels_per_ext_rel);
7933 rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
7934 if (!bed->elf_backend_emit_relocs (output_bfd, o,
7935 input_rel_hdr2,
7936 internal_relocs,
7937 rel_hash_list))
7938 return FALSE;
7943 /* Write out the modified section contents. */
7944 if (bed->elf_backend_write_section
7945 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7947 /* Section written out. */
7949 else switch (o->sec_info_type)
7951 case ELF_INFO_TYPE_STABS:
7952 if (! (_bfd_write_section_stabs
7953 (output_bfd,
7954 &elf_hash_table (finfo->info)->stab_info,
7955 o, &elf_section_data (o)->sec_info, contents)))
7956 return FALSE;
7957 break;
7958 case ELF_INFO_TYPE_MERGE:
7959 if (! _bfd_write_merged_section (output_bfd, o,
7960 elf_section_data (o)->sec_info))
7961 return FALSE;
7962 break;
7963 case ELF_INFO_TYPE_EH_FRAME:
7965 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7966 o, contents))
7967 return FALSE;
7969 break;
7970 default:
7972 if (! (o->flags & SEC_EXCLUDE)
7973 && ! bfd_set_section_contents (output_bfd, o->output_section,
7974 contents,
7975 (file_ptr) o->output_offset,
7976 o->size))
7977 return FALSE;
7979 break;
7983 return TRUE;
7986 /* Generate a reloc when linking an ELF file. This is a reloc
7987 requested by the linker, and does not come from any input file. This
7988 is used to build constructor and destructor tables when linking
7989 with -Ur. */
7991 static bfd_boolean
7992 elf_reloc_link_order (bfd *output_bfd,
7993 struct bfd_link_info *info,
7994 asection *output_section,
7995 struct bfd_link_order *link_order)
7997 reloc_howto_type *howto;
7998 long indx;
7999 bfd_vma offset;
8000 bfd_vma addend;
8001 struct elf_link_hash_entry **rel_hash_ptr;
8002 Elf_Internal_Shdr *rel_hdr;
8003 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
8004 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
8005 bfd_byte *erel;
8006 unsigned int i;
8008 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
8009 if (howto == NULL)
8011 bfd_set_error (bfd_error_bad_value);
8012 return FALSE;
8015 addend = link_order->u.reloc.p->addend;
8017 /* Figure out the symbol index. */
8018 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
8019 + elf_section_data (output_section)->rel_count
8020 + elf_section_data (output_section)->rel_count2);
8021 if (link_order->type == bfd_section_reloc_link_order)
8023 indx = link_order->u.reloc.p->u.section->target_index;
8024 BFD_ASSERT (indx != 0);
8025 *rel_hash_ptr = NULL;
8027 else
8029 struct elf_link_hash_entry *h;
8031 /* Treat a reloc against a defined symbol as though it were
8032 actually against the section. */
8033 h = ((struct elf_link_hash_entry *)
8034 bfd_wrapped_link_hash_lookup (output_bfd, info,
8035 link_order->u.reloc.p->u.name,
8036 FALSE, FALSE, TRUE));
8037 if (h != NULL
8038 && (h->root.type == bfd_link_hash_defined
8039 || h->root.type == bfd_link_hash_defweak))
8041 asection *section;
8043 section = h->root.u.def.section;
8044 indx = section->output_section->target_index;
8045 *rel_hash_ptr = NULL;
8046 /* It seems that we ought to add the symbol value to the
8047 addend here, but in practice it has already been added
8048 because it was passed to constructor_callback. */
8049 addend += section->output_section->vma + section->output_offset;
8051 else if (h != NULL)
8053 /* Setting the index to -2 tells elf_link_output_extsym that
8054 this symbol is used by a reloc. */
8055 h->indx = -2;
8056 *rel_hash_ptr = h;
8057 indx = 0;
8059 else
8061 if (! ((*info->callbacks->unattached_reloc)
8062 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
8063 return FALSE;
8064 indx = 0;
8068 /* If this is an inplace reloc, we must write the addend into the
8069 object file. */
8070 if (howto->partial_inplace && addend != 0)
8072 bfd_size_type size;
8073 bfd_reloc_status_type rstat;
8074 bfd_byte *buf;
8075 bfd_boolean ok;
8076 const char *sym_name;
8078 size = bfd_get_reloc_size (howto);
8079 buf = bfd_zmalloc (size);
8080 if (buf == NULL)
8081 return FALSE;
8082 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
8083 switch (rstat)
8085 case bfd_reloc_ok:
8086 break;
8088 default:
8089 case bfd_reloc_outofrange:
8090 abort ();
8092 case bfd_reloc_overflow:
8093 if (link_order->type == bfd_section_reloc_link_order)
8094 sym_name = bfd_section_name (output_bfd,
8095 link_order->u.reloc.p->u.section);
8096 else
8097 sym_name = link_order->u.reloc.p->u.name;
8098 if (! ((*info->callbacks->reloc_overflow)
8099 (info, NULL, sym_name, howto->name, addend, NULL,
8100 NULL, (bfd_vma) 0)))
8102 free (buf);
8103 return FALSE;
8105 break;
8107 ok = bfd_set_section_contents (output_bfd, output_section, buf,
8108 link_order->offset, size);
8109 free (buf);
8110 if (! ok)
8111 return FALSE;
8114 /* The address of a reloc is relative to the section in a
8115 relocatable file, and is a virtual address in an executable
8116 file. */
8117 offset = link_order->offset;
8118 if (! info->relocatable)
8119 offset += output_section->vma;
8121 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
8123 irel[i].r_offset = offset;
8124 irel[i].r_info = 0;
8125 irel[i].r_addend = 0;
8127 if (bed->s->arch_size == 32)
8128 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
8129 else
8130 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
8132 rel_hdr = &elf_section_data (output_section)->rel_hdr;
8133 erel = rel_hdr->contents;
8134 if (rel_hdr->sh_type == SHT_REL)
8136 erel += (elf_section_data (output_section)->rel_count
8137 * bed->s->sizeof_rel);
8138 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
8140 else
8142 irel[0].r_addend = addend;
8143 erel += (elf_section_data (output_section)->rel_count
8144 * bed->s->sizeof_rela);
8145 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
8148 ++elf_section_data (output_section)->rel_count;
8150 return TRUE;
8154 /* Get the output vma of the section pointed to by the sh_link field. */
8156 static bfd_vma
8157 elf_get_linked_section_vma (struct bfd_link_order *p)
8159 Elf_Internal_Shdr **elf_shdrp;
8160 asection *s;
8161 int elfsec;
8163 s = p->u.indirect.section;
8164 elf_shdrp = elf_elfsections (s->owner);
8165 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
8166 elfsec = elf_shdrp[elfsec]->sh_link;
8167 /* PR 290:
8168 The Intel C compiler generates SHT_IA_64_UNWIND with
8169 SHF_LINK_ORDER. But it doesn't set the sh_link or
8170 sh_info fields. Hence we could get the situation
8171 where elfsec is 0. */
8172 if (elfsec == 0)
8174 const struct elf_backend_data *bed
8175 = get_elf_backend_data (s->owner);
8176 if (bed->link_order_error_handler)
8177 bed->link_order_error_handler
8178 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
8179 return 0;
8181 else
8183 s = elf_shdrp[elfsec]->bfd_section;
8184 return s->output_section->vma + s->output_offset;
8189 /* Compare two sections based on the locations of the sections they are
8190 linked to. Used by elf_fixup_link_order. */
8192 static int
8193 compare_link_order (const void * a, const void * b)
8195 bfd_vma apos;
8196 bfd_vma bpos;
8198 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
8199 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
8200 if (apos < bpos)
8201 return -1;
8202 return apos > bpos;
8206 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
8207 order as their linked sections. Returns false if this could not be done
8208 because an output section includes both ordered and unordered
8209 sections. Ideally we'd do this in the linker proper. */
8211 static bfd_boolean
8212 elf_fixup_link_order (bfd *abfd, asection *o)
8214 int seen_linkorder;
8215 int seen_other;
8216 int n;
8217 struct bfd_link_order *p;
8218 bfd *sub;
8219 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8220 unsigned elfsec;
8221 struct bfd_link_order **sections;
8222 asection *s, *other_sec, *linkorder_sec;
8223 bfd_vma offset;
8225 other_sec = NULL;
8226 linkorder_sec = NULL;
8227 seen_other = 0;
8228 seen_linkorder = 0;
8229 for (p = o->map_head.link_order; p != NULL; p = p->next)
8231 if (p->type == bfd_indirect_link_order)
8233 s = p->u.indirect.section;
8234 sub = s->owner;
8235 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
8236 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass
8237 && (elfsec = _bfd_elf_section_from_bfd_section (sub, s))
8238 && elfsec < elf_numsections (sub)
8239 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
8241 seen_linkorder++;
8242 linkorder_sec = s;
8244 else
8246 seen_other++;
8247 other_sec = s;
8250 else
8251 seen_other++;
8253 if (seen_other && seen_linkorder)
8255 if (other_sec && linkorder_sec)
8256 (*_bfd_error_handler) (_("%A has both ordered [`%A' in %B] and unordered [`%A' in %B] sections"),
8257 o, linkorder_sec,
8258 linkorder_sec->owner, other_sec,
8259 other_sec->owner);
8260 else
8261 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
8263 bfd_set_error (bfd_error_bad_value);
8264 return FALSE;
8268 if (!seen_linkorder)
8269 return TRUE;
8271 sections = (struct bfd_link_order **)
8272 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
8273 seen_linkorder = 0;
8275 for (p = o->map_head.link_order; p != NULL; p = p->next)
8277 sections[seen_linkorder++] = p;
8279 /* Sort the input sections in the order of their linked section. */
8280 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
8281 compare_link_order);
8283 /* Change the offsets of the sections. */
8284 offset = 0;
8285 for (n = 0; n < seen_linkorder; n++)
8287 s = sections[n]->u.indirect.section;
8288 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
8289 s->output_offset = offset;
8290 sections[n]->offset = offset;
8291 offset += sections[n]->size;
8294 return TRUE;
8298 /* Do the final step of an ELF link. */
8300 bfd_boolean
8301 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
8303 bfd_boolean dynamic;
8304 bfd_boolean emit_relocs;
8305 bfd *dynobj;
8306 struct elf_final_link_info finfo;
8307 register asection *o;
8308 register struct bfd_link_order *p;
8309 register bfd *sub;
8310 bfd_size_type max_contents_size;
8311 bfd_size_type max_external_reloc_size;
8312 bfd_size_type max_internal_reloc_count;
8313 bfd_size_type max_sym_count;
8314 bfd_size_type max_sym_shndx_count;
8315 file_ptr off;
8316 Elf_Internal_Sym elfsym;
8317 unsigned int i;
8318 Elf_Internal_Shdr *symtab_hdr;
8319 Elf_Internal_Shdr *symtab_shndx_hdr;
8320 Elf_Internal_Shdr *symstrtab_hdr;
8321 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8322 struct elf_outext_info eoinfo;
8323 bfd_boolean merged;
8324 size_t relativecount = 0;
8325 asection *reldyn = 0;
8326 bfd_size_type amt;
8328 if (! is_elf_hash_table (info->hash))
8329 return FALSE;
8331 if (info->shared)
8332 abfd->flags |= DYNAMIC;
8334 dynamic = elf_hash_table (info)->dynamic_sections_created;
8335 dynobj = elf_hash_table (info)->dynobj;
8337 emit_relocs = (info->relocatable
8338 || info->emitrelocations);
8340 finfo.info = info;
8341 finfo.output_bfd = abfd;
8342 finfo.symstrtab = _bfd_elf_stringtab_init ();
8343 if (finfo.symstrtab == NULL)
8344 return FALSE;
8346 if (! dynamic)
8348 finfo.dynsym_sec = NULL;
8349 finfo.hash_sec = NULL;
8350 finfo.symver_sec = NULL;
8352 else
8354 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
8355 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
8356 BFD_ASSERT (finfo.dynsym_sec != NULL);
8357 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
8358 /* Note that it is OK if symver_sec is NULL. */
8361 finfo.contents = NULL;
8362 finfo.external_relocs = NULL;
8363 finfo.internal_relocs = NULL;
8364 finfo.external_syms = NULL;
8365 finfo.locsym_shndx = NULL;
8366 finfo.internal_syms = NULL;
8367 finfo.indices = NULL;
8368 finfo.sections = NULL;
8369 finfo.symbuf = NULL;
8370 finfo.symshndxbuf = NULL;
8371 finfo.symbuf_count = 0;
8372 finfo.shndxbuf_size = 0;
8374 /* Count up the number of relocations we will output for each output
8375 section, so that we know the sizes of the reloc sections. We
8376 also figure out some maximum sizes. */
8377 max_contents_size = 0;
8378 max_external_reloc_size = 0;
8379 max_internal_reloc_count = 0;
8380 max_sym_count = 0;
8381 max_sym_shndx_count = 0;
8382 merged = FALSE;
8383 for (o = abfd->sections; o != NULL; o = o->next)
8385 struct bfd_elf_section_data *esdo = elf_section_data (o);
8386 o->reloc_count = 0;
8388 for (p = o->map_head.link_order; p != NULL; p = p->next)
8390 unsigned int reloc_count = 0;
8391 struct bfd_elf_section_data *esdi = NULL;
8392 unsigned int *rel_count1;
8394 if (p->type == bfd_section_reloc_link_order
8395 || p->type == bfd_symbol_reloc_link_order)
8396 reloc_count = 1;
8397 else if (p->type == bfd_indirect_link_order)
8399 asection *sec;
8401 sec = p->u.indirect.section;
8402 esdi = elf_section_data (sec);
8404 /* Mark all sections which are to be included in the
8405 link. This will normally be every section. We need
8406 to do this so that we can identify any sections which
8407 the linker has decided to not include. */
8408 sec->linker_mark = TRUE;
8410 if (sec->flags & SEC_MERGE)
8411 merged = TRUE;
8413 if (info->relocatable || info->emitrelocations)
8414 reloc_count = sec->reloc_count;
8415 else if (bed->elf_backend_count_relocs)
8417 Elf_Internal_Rela * relocs;
8419 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
8420 info->keep_memory);
8422 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
8424 if (elf_section_data (o)->relocs != relocs)
8425 free (relocs);
8428 if (sec->rawsize > max_contents_size)
8429 max_contents_size = sec->rawsize;
8430 if (sec->size > max_contents_size)
8431 max_contents_size = sec->size;
8433 /* We are interested in just local symbols, not all
8434 symbols. */
8435 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
8436 && (sec->owner->flags & DYNAMIC) == 0)
8438 size_t sym_count;
8440 if (elf_bad_symtab (sec->owner))
8441 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
8442 / bed->s->sizeof_sym);
8443 else
8444 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
8446 if (sym_count > max_sym_count)
8447 max_sym_count = sym_count;
8449 if (sym_count > max_sym_shndx_count
8450 && elf_symtab_shndx (sec->owner) != 0)
8451 max_sym_shndx_count = sym_count;
8453 if ((sec->flags & SEC_RELOC) != 0)
8455 size_t ext_size;
8457 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
8458 if (ext_size > max_external_reloc_size)
8459 max_external_reloc_size = ext_size;
8460 if (sec->reloc_count > max_internal_reloc_count)
8461 max_internal_reloc_count = sec->reloc_count;
8466 if (reloc_count == 0)
8467 continue;
8469 o->reloc_count += reloc_count;
8471 /* MIPS may have a mix of REL and RELA relocs on sections.
8472 To support this curious ABI we keep reloc counts in
8473 elf_section_data too. We must be careful to add the
8474 relocations from the input section to the right output
8475 count. FIXME: Get rid of one count. We have
8476 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
8477 rel_count1 = &esdo->rel_count;
8478 if (esdi != NULL)
8480 bfd_boolean same_size;
8481 bfd_size_type entsize1;
8483 entsize1 = esdi->rel_hdr.sh_entsize;
8484 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
8485 || entsize1 == bed->s->sizeof_rela);
8486 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
8488 if (!same_size)
8489 rel_count1 = &esdo->rel_count2;
8491 if (esdi->rel_hdr2 != NULL)
8493 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
8494 unsigned int alt_count;
8495 unsigned int *rel_count2;
8497 BFD_ASSERT (entsize2 != entsize1
8498 && (entsize2 == bed->s->sizeof_rel
8499 || entsize2 == bed->s->sizeof_rela));
8501 rel_count2 = &esdo->rel_count2;
8502 if (!same_size)
8503 rel_count2 = &esdo->rel_count;
8505 /* The following is probably too simplistic if the
8506 backend counts output relocs unusually. */
8507 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
8508 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
8509 *rel_count2 += alt_count;
8510 reloc_count -= alt_count;
8513 *rel_count1 += reloc_count;
8516 if (o->reloc_count > 0)
8517 o->flags |= SEC_RELOC;
8518 else
8520 /* Explicitly clear the SEC_RELOC flag. The linker tends to
8521 set it (this is probably a bug) and if it is set
8522 assign_section_numbers will create a reloc section. */
8523 o->flags &=~ SEC_RELOC;
8526 /* If the SEC_ALLOC flag is not set, force the section VMA to
8527 zero. This is done in elf_fake_sections as well, but forcing
8528 the VMA to 0 here will ensure that relocs against these
8529 sections are handled correctly. */
8530 if ((o->flags & SEC_ALLOC) == 0
8531 && ! o->user_set_vma)
8532 o->vma = 0;
8535 if (! info->relocatable && merged)
8536 elf_link_hash_traverse (elf_hash_table (info),
8537 _bfd_elf_link_sec_merge_syms, abfd);
8539 /* Figure out the file positions for everything but the symbol table
8540 and the relocs. We set symcount to force assign_section_numbers
8541 to create a symbol table. */
8542 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
8543 BFD_ASSERT (! abfd->output_has_begun);
8544 if (! _bfd_elf_compute_section_file_positions (abfd, info))
8545 goto error_return;
8547 /* Set sizes, and assign file positions for reloc sections. */
8548 for (o = abfd->sections; o != NULL; o = o->next)
8550 if ((o->flags & SEC_RELOC) != 0)
8552 if (!(_bfd_elf_link_size_reloc_section
8553 (abfd, &elf_section_data (o)->rel_hdr, o)))
8554 goto error_return;
8556 if (elf_section_data (o)->rel_hdr2
8557 && !(_bfd_elf_link_size_reloc_section
8558 (abfd, elf_section_data (o)->rel_hdr2, o)))
8559 goto error_return;
8562 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
8563 to count upwards while actually outputting the relocations. */
8564 elf_section_data (o)->rel_count = 0;
8565 elf_section_data (o)->rel_count2 = 0;
8568 _bfd_elf_assign_file_positions_for_relocs (abfd);
8570 /* We have now assigned file positions for all the sections except
8571 .symtab and .strtab. We start the .symtab section at the current
8572 file position, and write directly to it. We build the .strtab
8573 section in memory. */
8574 bfd_get_symcount (abfd) = 0;
8575 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
8576 /* sh_name is set in prep_headers. */
8577 symtab_hdr->sh_type = SHT_SYMTAB;
8578 /* sh_flags, sh_addr and sh_size all start off zero. */
8579 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
8580 /* sh_link is set in assign_section_numbers. */
8581 /* sh_info is set below. */
8582 /* sh_offset is set just below. */
8583 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
8585 off = elf_tdata (abfd)->next_file_pos;
8586 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
8588 /* Note that at this point elf_tdata (abfd)->next_file_pos is
8589 incorrect. We do not yet know the size of the .symtab section.
8590 We correct next_file_pos below, after we do know the size. */
8592 /* Allocate a buffer to hold swapped out symbols. This is to avoid
8593 continuously seeking to the right position in the file. */
8594 if (! info->keep_memory || max_sym_count < 20)
8595 finfo.symbuf_size = 20;
8596 else
8597 finfo.symbuf_size = max_sym_count;
8598 amt = finfo.symbuf_size;
8599 amt *= bed->s->sizeof_sym;
8600 finfo.symbuf = bfd_malloc (amt);
8601 if (finfo.symbuf == NULL)
8602 goto error_return;
8603 if (elf_numsections (abfd) > SHN_LORESERVE)
8605 /* Wild guess at number of output symbols. realloc'd as needed. */
8606 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
8607 finfo.shndxbuf_size = amt;
8608 amt *= sizeof (Elf_External_Sym_Shndx);
8609 finfo.symshndxbuf = bfd_zmalloc (amt);
8610 if (finfo.symshndxbuf == NULL)
8611 goto error_return;
8614 /* Start writing out the symbol table. The first symbol is always a
8615 dummy symbol. */
8616 if (info->strip != strip_all
8617 || emit_relocs)
8619 elfsym.st_value = 0;
8620 elfsym.st_size = 0;
8621 elfsym.st_info = 0;
8622 elfsym.st_other = 0;
8623 elfsym.st_shndx = SHN_UNDEF;
8624 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
8625 NULL))
8626 goto error_return;
8629 /* Output a symbol for each section. We output these even if we are
8630 discarding local symbols, since they are used for relocs. These
8631 symbols have no names. We store the index of each one in the
8632 index field of the section, so that we can find it again when
8633 outputting relocs. */
8634 if (info->strip != strip_all
8635 || emit_relocs)
8637 elfsym.st_size = 0;
8638 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8639 elfsym.st_other = 0;
8640 elfsym.st_value = 0;
8641 for (i = 1; i < elf_numsections (abfd); i++)
8643 o = bfd_section_from_elf_index (abfd, i);
8644 if (o != NULL)
8646 o->target_index = bfd_get_symcount (abfd);
8647 elfsym.st_shndx = i;
8648 if (!info->relocatable)
8649 elfsym.st_value = o->vma;
8650 if (!elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
8651 goto error_return;
8653 if (i == SHN_LORESERVE - 1)
8654 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
8658 /* Allocate some memory to hold information read in from the input
8659 files. */
8660 if (max_contents_size != 0)
8662 finfo.contents = bfd_malloc (max_contents_size);
8663 if (finfo.contents == NULL)
8664 goto error_return;
8667 if (max_external_reloc_size != 0)
8669 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
8670 if (finfo.external_relocs == NULL)
8671 goto error_return;
8674 if (max_internal_reloc_count != 0)
8676 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
8677 amt *= sizeof (Elf_Internal_Rela);
8678 finfo.internal_relocs = bfd_malloc (amt);
8679 if (finfo.internal_relocs == NULL)
8680 goto error_return;
8683 if (max_sym_count != 0)
8685 amt = max_sym_count * bed->s->sizeof_sym;
8686 finfo.external_syms = bfd_malloc (amt);
8687 if (finfo.external_syms == NULL)
8688 goto error_return;
8690 amt = max_sym_count * sizeof (Elf_Internal_Sym);
8691 finfo.internal_syms = bfd_malloc (amt);
8692 if (finfo.internal_syms == NULL)
8693 goto error_return;
8695 amt = max_sym_count * sizeof (long);
8696 finfo.indices = bfd_malloc (amt);
8697 if (finfo.indices == NULL)
8698 goto error_return;
8700 amt = max_sym_count * sizeof (asection *);
8701 finfo.sections = bfd_malloc (amt);
8702 if (finfo.sections == NULL)
8703 goto error_return;
8706 if (max_sym_shndx_count != 0)
8708 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8709 finfo.locsym_shndx = bfd_malloc (amt);
8710 if (finfo.locsym_shndx == NULL)
8711 goto error_return;
8714 if (elf_hash_table (info)->tls_sec)
8716 bfd_vma base, end = 0;
8717 asection *sec;
8719 for (sec = elf_hash_table (info)->tls_sec;
8720 sec && (sec->flags & SEC_THREAD_LOCAL);
8721 sec = sec->next)
8723 bfd_size_type size = sec->size;
8725 if (size == 0
8726 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8728 struct bfd_link_order *o = sec->map_tail.link_order;
8729 if (o != NULL)
8730 size = o->offset + o->size;
8732 end = sec->vma + size;
8734 base = elf_hash_table (info)->tls_sec->vma;
8735 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8736 elf_hash_table (info)->tls_size = end - base;
8739 /* Reorder SHF_LINK_ORDER sections. */
8740 for (o = abfd->sections; o != NULL; o = o->next)
8742 if (!elf_fixup_link_order (abfd, o))
8743 return FALSE;
8746 /* Since ELF permits relocations to be against local symbols, we
8747 must have the local symbols available when we do the relocations.
8748 Since we would rather only read the local symbols once, and we
8749 would rather not keep them in memory, we handle all the
8750 relocations for a single input file at the same time.
8752 Unfortunately, there is no way to know the total number of local
8753 symbols until we have seen all of them, and the local symbol
8754 indices precede the global symbol indices. This means that when
8755 we are generating relocatable output, and we see a reloc against
8756 a global symbol, we can not know the symbol index until we have
8757 finished examining all the local symbols to see which ones we are
8758 going to output. To deal with this, we keep the relocations in
8759 memory, and don't output them until the end of the link. This is
8760 an unfortunate waste of memory, but I don't see a good way around
8761 it. Fortunately, it only happens when performing a relocatable
8762 link, which is not the common case. FIXME: If keep_memory is set
8763 we could write the relocs out and then read them again; I don't
8764 know how bad the memory loss will be. */
8766 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8767 sub->output_has_begun = FALSE;
8768 for (o = abfd->sections; o != NULL; o = o->next)
8770 for (p = o->map_head.link_order; p != NULL; p = p->next)
8772 if (p->type == bfd_indirect_link_order
8773 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8774 == bfd_target_elf_flavour)
8775 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8777 if (! sub->output_has_begun)
8779 if (! elf_link_input_bfd (&finfo, sub))
8780 goto error_return;
8781 sub->output_has_begun = TRUE;
8784 else if (p->type == bfd_section_reloc_link_order
8785 || p->type == bfd_symbol_reloc_link_order)
8787 if (! elf_reloc_link_order (abfd, info, o, p))
8788 goto error_return;
8790 else
8792 if (! _bfd_default_link_order (abfd, info, o, p))
8793 goto error_return;
8798 /* Free symbol buffer if needed. */
8799 if (!info->reduce_memory_overheads)
8801 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8802 if (elf_tdata (sub)->symbuf)
8804 free (elf_tdata (sub)->symbuf);
8805 elf_tdata (sub)->symbuf = NULL;
8809 /* Output any global symbols that got converted to local in a
8810 version script or due to symbol visibility. We do this in a
8811 separate step since ELF requires all local symbols to appear
8812 prior to any global symbols. FIXME: We should only do this if
8813 some global symbols were, in fact, converted to become local.
8814 FIXME: Will this work correctly with the Irix 5 linker? */
8815 eoinfo.failed = FALSE;
8816 eoinfo.finfo = &finfo;
8817 eoinfo.localsyms = TRUE;
8818 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8819 &eoinfo);
8820 if (eoinfo.failed)
8821 return FALSE;
8823 /* If backend needs to output some local symbols not present in the hash
8824 table, do it now. */
8825 if (bed->elf_backend_output_arch_local_syms)
8827 typedef bfd_boolean (*out_sym_func)
8828 (void *, const char *, Elf_Internal_Sym *, asection *,
8829 struct elf_link_hash_entry *);
8831 if (! ((*bed->elf_backend_output_arch_local_syms)
8832 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8833 return FALSE;
8836 /* That wrote out all the local symbols. Finish up the symbol table
8837 with the global symbols. Even if we want to strip everything we
8838 can, we still need to deal with those global symbols that got
8839 converted to local in a version script. */
8841 /* The sh_info field records the index of the first non local symbol. */
8842 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8844 if (dynamic
8845 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8847 Elf_Internal_Sym sym;
8848 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8849 long last_local = 0;
8851 /* Write out the section symbols for the output sections. */
8852 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
8854 asection *s;
8856 sym.st_size = 0;
8857 sym.st_name = 0;
8858 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8859 sym.st_other = 0;
8861 for (s = abfd->sections; s != NULL; s = s->next)
8863 int indx;
8864 bfd_byte *dest;
8865 long dynindx;
8867 dynindx = elf_section_data (s)->dynindx;
8868 if (dynindx <= 0)
8869 continue;
8870 indx = elf_section_data (s)->this_idx;
8871 BFD_ASSERT (indx > 0);
8872 sym.st_shndx = indx;
8873 if (! check_dynsym (abfd, &sym))
8874 return FALSE;
8875 sym.st_value = s->vma;
8876 dest = dynsym + dynindx * bed->s->sizeof_sym;
8877 if (last_local < dynindx)
8878 last_local = dynindx;
8879 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8883 /* Write out the local dynsyms. */
8884 if (elf_hash_table (info)->dynlocal)
8886 struct elf_link_local_dynamic_entry *e;
8887 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8889 asection *s;
8890 bfd_byte *dest;
8892 sym.st_size = e->isym.st_size;
8893 sym.st_other = e->isym.st_other;
8895 /* Copy the internal symbol as is.
8896 Note that we saved a word of storage and overwrote
8897 the original st_name with the dynstr_index. */
8898 sym = e->isym;
8900 if (e->isym.st_shndx != SHN_UNDEF
8901 && (e->isym.st_shndx < SHN_LORESERVE
8902 || e->isym.st_shndx > SHN_HIRESERVE))
8904 s = bfd_section_from_elf_index (e->input_bfd,
8905 e->isym.st_shndx);
8907 sym.st_shndx =
8908 elf_section_data (s->output_section)->this_idx;
8909 if (! check_dynsym (abfd, &sym))
8910 return FALSE;
8911 sym.st_value = (s->output_section->vma
8912 + s->output_offset
8913 + e->isym.st_value);
8916 if (last_local < e->dynindx)
8917 last_local = e->dynindx;
8919 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8920 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8924 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8925 last_local + 1;
8928 /* We get the global symbols from the hash table. */
8929 eoinfo.failed = FALSE;
8930 eoinfo.localsyms = FALSE;
8931 eoinfo.finfo = &finfo;
8932 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8933 &eoinfo);
8934 if (eoinfo.failed)
8935 return FALSE;
8937 /* If backend needs to output some symbols not present in the hash
8938 table, do it now. */
8939 if (bed->elf_backend_output_arch_syms)
8941 typedef bfd_boolean (*out_sym_func)
8942 (void *, const char *, Elf_Internal_Sym *, asection *,
8943 struct elf_link_hash_entry *);
8945 if (! ((*bed->elf_backend_output_arch_syms)
8946 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8947 return FALSE;
8950 /* Flush all symbols to the file. */
8951 if (! elf_link_flush_output_syms (&finfo, bed))
8952 return FALSE;
8954 /* Now we know the size of the symtab section. */
8955 off += symtab_hdr->sh_size;
8957 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8958 if (symtab_shndx_hdr->sh_name != 0)
8960 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8961 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8962 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8963 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8964 symtab_shndx_hdr->sh_size = amt;
8966 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8967 off, TRUE);
8969 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8970 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8971 return FALSE;
8975 /* Finish up and write out the symbol string table (.strtab)
8976 section. */
8977 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8978 /* sh_name was set in prep_headers. */
8979 symstrtab_hdr->sh_type = SHT_STRTAB;
8980 symstrtab_hdr->sh_flags = 0;
8981 symstrtab_hdr->sh_addr = 0;
8982 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8983 symstrtab_hdr->sh_entsize = 0;
8984 symstrtab_hdr->sh_link = 0;
8985 symstrtab_hdr->sh_info = 0;
8986 /* sh_offset is set just below. */
8987 symstrtab_hdr->sh_addralign = 1;
8989 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8990 elf_tdata (abfd)->next_file_pos = off;
8992 if (bfd_get_symcount (abfd) > 0)
8994 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8995 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8996 return FALSE;
8999 /* Adjust the relocs to have the correct symbol indices. */
9000 for (o = abfd->sections; o != NULL; o = o->next)
9002 if ((o->flags & SEC_RELOC) == 0)
9003 continue;
9005 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
9006 elf_section_data (o)->rel_count,
9007 elf_section_data (o)->rel_hashes);
9008 if (elf_section_data (o)->rel_hdr2 != NULL)
9009 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
9010 elf_section_data (o)->rel_count2,
9011 (elf_section_data (o)->rel_hashes
9012 + elf_section_data (o)->rel_count));
9014 /* Set the reloc_count field to 0 to prevent write_relocs from
9015 trying to swap the relocs out itself. */
9016 o->reloc_count = 0;
9019 if (dynamic && info->combreloc && dynobj != NULL)
9020 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
9022 /* If we are linking against a dynamic object, or generating a
9023 shared library, finish up the dynamic linking information. */
9024 if (dynamic)
9026 bfd_byte *dyncon, *dynconend;
9028 /* Fix up .dynamic entries. */
9029 o = bfd_get_section_by_name (dynobj, ".dynamic");
9030 BFD_ASSERT (o != NULL);
9032 dyncon = o->contents;
9033 dynconend = o->contents + o->size;
9034 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
9036 Elf_Internal_Dyn dyn;
9037 const char *name;
9038 unsigned int type;
9040 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
9042 switch (dyn.d_tag)
9044 default:
9045 continue;
9046 case DT_NULL:
9047 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
9049 switch (elf_section_data (reldyn)->this_hdr.sh_type)
9051 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
9052 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
9053 default: continue;
9055 dyn.d_un.d_val = relativecount;
9056 relativecount = 0;
9057 break;
9059 continue;
9061 case DT_INIT:
9062 name = info->init_function;
9063 goto get_sym;
9064 case DT_FINI:
9065 name = info->fini_function;
9066 get_sym:
9068 struct elf_link_hash_entry *h;
9070 h = elf_link_hash_lookup (elf_hash_table (info), name,
9071 FALSE, FALSE, TRUE);
9072 if (h != NULL
9073 && (h->root.type == bfd_link_hash_defined
9074 || h->root.type == bfd_link_hash_defweak))
9076 dyn.d_un.d_val = h->root.u.def.value;
9077 o = h->root.u.def.section;
9078 if (o->output_section != NULL)
9079 dyn.d_un.d_val += (o->output_section->vma
9080 + o->output_offset);
9081 else
9083 /* The symbol is imported from another shared
9084 library and does not apply to this one. */
9085 dyn.d_un.d_val = 0;
9087 break;
9090 continue;
9092 case DT_PREINIT_ARRAYSZ:
9093 name = ".preinit_array";
9094 goto get_size;
9095 case DT_INIT_ARRAYSZ:
9096 name = ".init_array";
9097 goto get_size;
9098 case DT_FINI_ARRAYSZ:
9099 name = ".fini_array";
9100 get_size:
9101 o = bfd_get_section_by_name (abfd, name);
9102 if (o == NULL)
9104 (*_bfd_error_handler)
9105 (_("%B: could not find output section %s"), abfd, name);
9106 goto error_return;
9108 if (o->size == 0)
9109 (*_bfd_error_handler)
9110 (_("warning: %s section has zero size"), name);
9111 dyn.d_un.d_val = o->size;
9112 break;
9114 case DT_PREINIT_ARRAY:
9115 name = ".preinit_array";
9116 goto get_vma;
9117 case DT_INIT_ARRAY:
9118 name = ".init_array";
9119 goto get_vma;
9120 case DT_FINI_ARRAY:
9121 name = ".fini_array";
9122 goto get_vma;
9124 case DT_HASH:
9125 name = ".hash";
9126 goto get_vma;
9127 case DT_GNU_HASH:
9128 name = ".gnu.hash";
9129 goto get_vma;
9130 case DT_STRTAB:
9131 name = ".dynstr";
9132 goto get_vma;
9133 case DT_SYMTAB:
9134 name = ".dynsym";
9135 goto get_vma;
9136 case DT_VERDEF:
9137 name = ".gnu.version_d";
9138 goto get_vma;
9139 case DT_VERNEED:
9140 name = ".gnu.version_r";
9141 goto get_vma;
9142 case DT_VERSYM:
9143 name = ".gnu.version";
9144 get_vma:
9145 o = bfd_get_section_by_name (abfd, name);
9146 if (o == NULL)
9148 (*_bfd_error_handler)
9149 (_("%B: could not find output section %s"), abfd, name);
9150 goto error_return;
9152 dyn.d_un.d_ptr = o->vma;
9153 break;
9155 case DT_REL:
9156 case DT_RELA:
9157 case DT_RELSZ:
9158 case DT_RELASZ:
9159 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
9160 type = SHT_REL;
9161 else
9162 type = SHT_RELA;
9163 dyn.d_un.d_val = 0;
9164 for (i = 1; i < elf_numsections (abfd); i++)
9166 Elf_Internal_Shdr *hdr;
9168 hdr = elf_elfsections (abfd)[i];
9169 if (hdr->sh_type == type
9170 && (hdr->sh_flags & SHF_ALLOC) != 0)
9172 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
9173 dyn.d_un.d_val += hdr->sh_size;
9174 else
9176 if (dyn.d_un.d_val == 0
9177 || hdr->sh_addr < dyn.d_un.d_val)
9178 dyn.d_un.d_val = hdr->sh_addr;
9182 break;
9184 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
9188 /* If we have created any dynamic sections, then output them. */
9189 if (dynobj != NULL)
9191 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
9192 goto error_return;
9194 /* Check for DT_TEXTREL (late, in case the backend removes it). */
9195 if (info->warn_shared_textrel && info->shared)
9197 bfd_byte *dyncon, *dynconend;
9199 /* Fix up .dynamic entries. */
9200 o = bfd_get_section_by_name (dynobj, ".dynamic");
9201 BFD_ASSERT (o != NULL);
9203 dyncon = o->contents;
9204 dynconend = o->contents + o->size;
9205 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
9207 Elf_Internal_Dyn dyn;
9209 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
9211 if (dyn.d_tag == DT_TEXTREL)
9213 _bfd_error_handler
9214 (_("warning: creating a DT_TEXTREL in a shared object."));
9215 break;
9220 for (o = dynobj->sections; o != NULL; o = o->next)
9222 if ((o->flags & SEC_HAS_CONTENTS) == 0
9223 || o->size == 0
9224 || o->output_section == bfd_abs_section_ptr)
9225 continue;
9226 if ((o->flags & SEC_LINKER_CREATED) == 0)
9228 /* At this point, we are only interested in sections
9229 created by _bfd_elf_link_create_dynamic_sections. */
9230 continue;
9232 if (elf_hash_table (info)->stab_info.stabstr == o)
9233 continue;
9234 if (elf_hash_table (info)->eh_info.hdr_sec == o)
9235 continue;
9236 if ((elf_section_data (o->output_section)->this_hdr.sh_type
9237 != SHT_STRTAB)
9238 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
9240 if (! bfd_set_section_contents (abfd, o->output_section,
9241 o->contents,
9242 (file_ptr) o->output_offset,
9243 o->size))
9244 goto error_return;
9246 else
9248 /* The contents of the .dynstr section are actually in a
9249 stringtab. */
9250 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
9251 if (bfd_seek (abfd, off, SEEK_SET) != 0
9252 || ! _bfd_elf_strtab_emit (abfd,
9253 elf_hash_table (info)->dynstr))
9254 goto error_return;
9259 if (info->relocatable)
9261 bfd_boolean failed = FALSE;
9263 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
9264 if (failed)
9265 goto error_return;
9268 /* If we have optimized stabs strings, output them. */
9269 if (elf_hash_table (info)->stab_info.stabstr != NULL)
9271 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
9272 goto error_return;
9275 if (info->eh_frame_hdr)
9277 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
9278 goto error_return;
9281 if (finfo.symstrtab != NULL)
9282 _bfd_stringtab_free (finfo.symstrtab);
9283 if (finfo.contents != NULL)
9284 free (finfo.contents);
9285 if (finfo.external_relocs != NULL)
9286 free (finfo.external_relocs);
9287 if (finfo.internal_relocs != NULL)
9288 free (finfo.internal_relocs);
9289 if (finfo.external_syms != NULL)
9290 free (finfo.external_syms);
9291 if (finfo.locsym_shndx != NULL)
9292 free (finfo.locsym_shndx);
9293 if (finfo.internal_syms != NULL)
9294 free (finfo.internal_syms);
9295 if (finfo.indices != NULL)
9296 free (finfo.indices);
9297 if (finfo.sections != NULL)
9298 free (finfo.sections);
9299 if (finfo.symbuf != NULL)
9300 free (finfo.symbuf);
9301 if (finfo.symshndxbuf != NULL)
9302 free (finfo.symshndxbuf);
9303 for (o = abfd->sections; o != NULL; o = o->next)
9305 if ((o->flags & SEC_RELOC) != 0
9306 && elf_section_data (o)->rel_hashes != NULL)
9307 free (elf_section_data (o)->rel_hashes);
9310 elf_tdata (abfd)->linker = TRUE;
9312 return TRUE;
9314 error_return:
9315 if (finfo.symstrtab != NULL)
9316 _bfd_stringtab_free (finfo.symstrtab);
9317 if (finfo.contents != NULL)
9318 free (finfo.contents);
9319 if (finfo.external_relocs != NULL)
9320 free (finfo.external_relocs);
9321 if (finfo.internal_relocs != NULL)
9322 free (finfo.internal_relocs);
9323 if (finfo.external_syms != NULL)
9324 free (finfo.external_syms);
9325 if (finfo.locsym_shndx != NULL)
9326 free (finfo.locsym_shndx);
9327 if (finfo.internal_syms != NULL)
9328 free (finfo.internal_syms);
9329 if (finfo.indices != NULL)
9330 free (finfo.indices);
9331 if (finfo.sections != NULL)
9332 free (finfo.sections);
9333 if (finfo.symbuf != NULL)
9334 free (finfo.symbuf);
9335 if (finfo.symshndxbuf != NULL)
9336 free (finfo.symshndxbuf);
9337 for (o = abfd->sections; o != NULL; o = o->next)
9339 if ((o->flags & SEC_RELOC) != 0
9340 && elf_section_data (o)->rel_hashes != NULL)
9341 free (elf_section_data (o)->rel_hashes);
9344 return FALSE;
9347 /* Garbage collect unused sections. */
9349 typedef asection * (*gc_mark_hook_fn)
9350 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9351 struct elf_link_hash_entry *, Elf_Internal_Sym *);
9353 /* Default gc_mark_hook. */
9355 asection *
9356 _bfd_elf_gc_mark_hook (asection *sec,
9357 struct bfd_link_info *info ATTRIBUTE_UNUSED,
9358 Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
9359 struct elf_link_hash_entry *h,
9360 Elf_Internal_Sym *sym)
9362 if (h != NULL)
9364 switch (h->root.type)
9366 case bfd_link_hash_defined:
9367 case bfd_link_hash_defweak:
9368 return h->root.u.def.section;
9370 case bfd_link_hash_common:
9371 return h->root.u.c.p->section;
9373 default:
9374 break;
9377 else
9378 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
9380 return NULL;
9383 /* The mark phase of garbage collection. For a given section, mark
9384 it and any sections in this section's group, and all the sections
9385 which define symbols to which it refers. */
9387 bfd_boolean
9388 _bfd_elf_gc_mark (struct bfd_link_info *info,
9389 asection *sec,
9390 gc_mark_hook_fn gc_mark_hook)
9392 bfd_boolean ret;
9393 bfd_boolean is_eh;
9394 asection *group_sec;
9396 sec->gc_mark = 1;
9398 /* Mark all the sections in the group. */
9399 group_sec = elf_section_data (sec)->next_in_group;
9400 if (group_sec && !group_sec->gc_mark)
9401 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
9402 return FALSE;
9404 /* Look through the section relocs. */
9405 ret = TRUE;
9406 is_eh = strcmp (sec->name, ".eh_frame") == 0;
9407 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
9409 Elf_Internal_Rela *relstart, *rel, *relend;
9410 Elf_Internal_Shdr *symtab_hdr;
9411 struct elf_link_hash_entry **sym_hashes;
9412 size_t nlocsyms;
9413 size_t extsymoff;
9414 bfd *input_bfd = sec->owner;
9415 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
9416 Elf_Internal_Sym *isym = NULL;
9417 int r_sym_shift;
9419 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
9420 sym_hashes = elf_sym_hashes (input_bfd);
9422 /* Read the local symbols. */
9423 if (elf_bad_symtab (input_bfd))
9425 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
9426 extsymoff = 0;
9428 else
9429 extsymoff = nlocsyms = symtab_hdr->sh_info;
9431 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
9432 if (isym == NULL && nlocsyms != 0)
9434 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
9435 NULL, NULL, NULL);
9436 if (isym == NULL)
9437 return FALSE;
9440 /* Read the relocations. */
9441 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
9442 info->keep_memory);
9443 if (relstart == NULL)
9445 ret = FALSE;
9446 goto out1;
9448 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
9450 if (bed->s->arch_size == 32)
9451 r_sym_shift = 8;
9452 else
9453 r_sym_shift = 32;
9455 for (rel = relstart; rel < relend; rel++)
9457 unsigned long r_symndx;
9458 asection *rsec;
9459 struct elf_link_hash_entry *h;
9461 r_symndx = rel->r_info >> r_sym_shift;
9462 if (r_symndx == 0)
9463 continue;
9465 if (r_symndx >= nlocsyms
9466 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
9468 h = sym_hashes[r_symndx - extsymoff];
9469 while (h->root.type == bfd_link_hash_indirect
9470 || h->root.type == bfd_link_hash_warning)
9471 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9472 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
9474 else
9476 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
9479 if (rsec && !rsec->gc_mark)
9481 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
9482 rsec->gc_mark = 1;
9483 else if (is_eh)
9484 rsec->gc_mark_from_eh = 1;
9485 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
9487 ret = FALSE;
9488 goto out2;
9493 out2:
9494 if (elf_section_data (sec)->relocs != relstart)
9495 free (relstart);
9496 out1:
9497 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
9499 if (! info->keep_memory)
9500 free (isym);
9501 else
9502 symtab_hdr->contents = (unsigned char *) isym;
9506 return ret;
9509 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
9511 struct elf_gc_sweep_symbol_info
9513 struct bfd_link_info *info;
9514 void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
9515 bfd_boolean);
9518 static bfd_boolean
9519 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
9521 if (h->root.type == bfd_link_hash_warning)
9522 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9524 if ((h->root.type == bfd_link_hash_defined
9525 || h->root.type == bfd_link_hash_defweak)
9526 && !h->root.u.def.section->gc_mark
9527 && !(h->root.u.def.section->owner->flags & DYNAMIC))
9529 struct elf_gc_sweep_symbol_info *inf = data;
9530 (*inf->hide_symbol) (inf->info, h, TRUE);
9533 return TRUE;
9536 /* The sweep phase of garbage collection. Remove all garbage sections. */
9538 typedef bfd_boolean (*gc_sweep_hook_fn)
9539 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
9541 static bfd_boolean
9542 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
9544 bfd *sub;
9545 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9546 gc_sweep_hook_fn gc_sweep_hook = bed->gc_sweep_hook;
9547 unsigned long section_sym_count;
9548 struct elf_gc_sweep_symbol_info sweep_info;
9550 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9552 asection *o;
9554 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9555 continue;
9557 for (o = sub->sections; o != NULL; o = o->next)
9559 /* Keep debug and special sections. */
9560 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
9561 || (o->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0)
9562 o->gc_mark = 1;
9564 if (o->gc_mark)
9565 continue;
9567 /* Skip sweeping sections already excluded. */
9568 if (o->flags & SEC_EXCLUDE)
9569 continue;
9571 /* Since this is early in the link process, it is simple
9572 to remove a section from the output. */
9573 o->flags |= SEC_EXCLUDE;
9575 if (info->print_gc_sections == TRUE)
9576 _bfd_error_handler (_("Removing unused section '%s' in file '%B'"), sub, o->name);
9578 /* But we also have to update some of the relocation
9579 info we collected before. */
9580 if (gc_sweep_hook
9581 && (o->flags & SEC_RELOC) != 0
9582 && o->reloc_count > 0
9583 && !bfd_is_abs_section (o->output_section))
9585 Elf_Internal_Rela *internal_relocs;
9586 bfd_boolean r;
9588 internal_relocs
9589 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
9590 info->keep_memory);
9591 if (internal_relocs == NULL)
9592 return FALSE;
9594 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
9596 if (elf_section_data (o)->relocs != internal_relocs)
9597 free (internal_relocs);
9599 if (!r)
9600 return FALSE;
9605 /* Remove the symbols that were in the swept sections from the dynamic
9606 symbol table. GCFIXME: Anyone know how to get them out of the
9607 static symbol table as well? */
9608 sweep_info.info = info;
9609 sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
9610 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
9611 &sweep_info);
9613 _bfd_elf_link_renumber_dynsyms (abfd, info, &section_sym_count);
9614 return TRUE;
9617 /* Propagate collected vtable information. This is called through
9618 elf_link_hash_traverse. */
9620 static bfd_boolean
9621 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
9623 if (h->root.type == bfd_link_hash_warning)
9624 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9626 /* Those that are not vtables. */
9627 if (h->vtable == NULL || h->vtable->parent == NULL)
9628 return TRUE;
9630 /* Those vtables that do not have parents, we cannot merge. */
9631 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
9632 return TRUE;
9634 /* If we've already been done, exit. */
9635 if (h->vtable->used && h->vtable->used[-1])
9636 return TRUE;
9638 /* Make sure the parent's table is up to date. */
9639 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
9641 if (h->vtable->used == NULL)
9643 /* None of this table's entries were referenced. Re-use the
9644 parent's table. */
9645 h->vtable->used = h->vtable->parent->vtable->used;
9646 h->vtable->size = h->vtable->parent->vtable->size;
9648 else
9650 size_t n;
9651 bfd_boolean *cu, *pu;
9653 /* Or the parent's entries into ours. */
9654 cu = h->vtable->used;
9655 cu[-1] = TRUE;
9656 pu = h->vtable->parent->vtable->used;
9657 if (pu != NULL)
9659 const struct elf_backend_data *bed;
9660 unsigned int log_file_align;
9662 bed = get_elf_backend_data (h->root.u.def.section->owner);
9663 log_file_align = bed->s->log_file_align;
9664 n = h->vtable->parent->vtable->size >> log_file_align;
9665 while (n--)
9667 if (*pu)
9668 *cu = TRUE;
9669 pu++;
9670 cu++;
9675 return TRUE;
9678 static bfd_boolean
9679 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
9681 asection *sec;
9682 bfd_vma hstart, hend;
9683 Elf_Internal_Rela *relstart, *relend, *rel;
9684 const struct elf_backend_data *bed;
9685 unsigned int log_file_align;
9687 if (h->root.type == bfd_link_hash_warning)
9688 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9690 /* Take care of both those symbols that do not describe vtables as
9691 well as those that are not loaded. */
9692 if (h->vtable == NULL || h->vtable->parent == NULL)
9693 return TRUE;
9695 BFD_ASSERT (h->root.type == bfd_link_hash_defined
9696 || h->root.type == bfd_link_hash_defweak);
9698 sec = h->root.u.def.section;
9699 hstart = h->root.u.def.value;
9700 hend = hstart + h->size;
9702 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
9703 if (!relstart)
9704 return *(bfd_boolean *) okp = FALSE;
9705 bed = get_elf_backend_data (sec->owner);
9706 log_file_align = bed->s->log_file_align;
9708 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
9710 for (rel = relstart; rel < relend; ++rel)
9711 if (rel->r_offset >= hstart && rel->r_offset < hend)
9713 /* If the entry is in use, do nothing. */
9714 if (h->vtable->used
9715 && (rel->r_offset - hstart) < h->vtable->size)
9717 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
9718 if (h->vtable->used[entry])
9719 continue;
9721 /* Otherwise, kill it. */
9722 rel->r_offset = rel->r_info = rel->r_addend = 0;
9725 return TRUE;
9728 /* Mark sections containing dynamically referenced symbols. When
9729 building shared libraries, we must assume that any visible symbol is
9730 referenced. */
9732 bfd_boolean
9733 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
9735 struct bfd_link_info *info = (struct bfd_link_info *) inf;
9737 if (h->root.type == bfd_link_hash_warning)
9738 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9740 if ((h->root.type == bfd_link_hash_defined
9741 || h->root.type == bfd_link_hash_defweak)
9742 && (h->ref_dynamic
9743 || (!info->executable
9744 && h->def_regular
9745 && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
9746 && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN)))
9747 h->root.u.def.section->flags |= SEC_KEEP;
9749 return TRUE;
9752 /* Do mark and sweep of unused sections. */
9754 bfd_boolean
9755 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
9757 bfd_boolean ok = TRUE;
9758 bfd *sub;
9759 asection * (*gc_mark_hook)
9760 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9761 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
9762 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9764 if (!bed->can_gc_sections
9765 || info->relocatable
9766 || info->emitrelocations
9767 || !is_elf_hash_table (info->hash))
9769 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
9770 return TRUE;
9773 /* Apply transitive closure to the vtable entry usage info. */
9774 elf_link_hash_traverse (elf_hash_table (info),
9775 elf_gc_propagate_vtable_entries_used,
9776 &ok);
9777 if (!ok)
9778 return FALSE;
9780 /* Kill the vtable relocations that were not used. */
9781 elf_link_hash_traverse (elf_hash_table (info),
9782 elf_gc_smash_unused_vtentry_relocs,
9783 &ok);
9784 if (!ok)
9785 return FALSE;
9787 /* Mark dynamically referenced symbols. */
9788 if (elf_hash_table (info)->dynamic_sections_created)
9789 elf_link_hash_traverse (elf_hash_table (info),
9790 bed->gc_mark_dynamic_ref,
9791 info);
9793 /* Grovel through relocs to find out who stays ... */
9794 gc_mark_hook = bed->gc_mark_hook;
9795 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9797 asection *o;
9799 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9800 continue;
9802 for (o = sub->sections; o != NULL; o = o->next)
9803 if ((o->flags & (SEC_EXCLUDE | SEC_KEEP)) == SEC_KEEP && !o->gc_mark)
9804 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9805 return FALSE;
9808 /* ... again for sections marked from eh_frame. */
9809 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9811 asection *o;
9813 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9814 continue;
9816 /* Keep .gcc_except_table.* if the associated .text.* (or the
9817 associated .gnu.linkonce.t.* if .text.* doesn't exist) is
9818 marked. This isn't very nice, but the proper solution,
9819 splitting .eh_frame up and using comdat doesn't pan out
9820 easily due to needing special relocs to handle the
9821 difference of two symbols in separate sections.
9822 Don't keep code sections referenced by .eh_frame. */
9823 #define TEXT_PREFIX ".text."
9824 #define TEXT_PREFIX2 ".gnu.linkonce.t."
9825 #define GCC_EXCEPT_TABLE_PREFIX ".gcc_except_table."
9826 for (o = sub->sections; o != NULL; o = o->next)
9827 if (!o->gc_mark && o->gc_mark_from_eh && (o->flags & SEC_CODE) == 0)
9829 if (CONST_STRNEQ (o->name, GCC_EXCEPT_TABLE_PREFIX))
9831 char *fn_name;
9832 const char *sec_name;
9833 asection *fn_text;
9834 unsigned o_name_prefix_len , fn_name_prefix_len, tmp;
9836 o_name_prefix_len = strlen (GCC_EXCEPT_TABLE_PREFIX);
9837 sec_name = o->name + o_name_prefix_len;
9838 fn_name_prefix_len = strlen (TEXT_PREFIX);
9839 tmp = strlen (TEXT_PREFIX2);
9840 if (tmp > fn_name_prefix_len)
9841 fn_name_prefix_len = tmp;
9842 fn_name
9843 = bfd_malloc (fn_name_prefix_len + strlen (sec_name) + 1);
9844 if (fn_name == NULL)
9845 return FALSE;
9847 /* Try the first prefix. */
9848 sprintf (fn_name, "%s%s", TEXT_PREFIX, sec_name);
9849 fn_text = bfd_get_section_by_name (sub, fn_name);
9851 /* Try the second prefix. */
9852 if (fn_text == NULL)
9854 sprintf (fn_name, "%s%s", TEXT_PREFIX2, sec_name);
9855 fn_text = bfd_get_section_by_name (sub, fn_name);
9858 free (fn_name);
9859 if (fn_text == NULL || !fn_text->gc_mark)
9860 continue;
9863 /* If not using specially named exception table section,
9864 then keep whatever we are using. */
9865 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9866 return FALSE;
9870 /* ... and mark SEC_EXCLUDE for those that go. */
9871 return elf_gc_sweep (abfd, info);
9874 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9876 bfd_boolean
9877 bfd_elf_gc_record_vtinherit (bfd *abfd,
9878 asection *sec,
9879 struct elf_link_hash_entry *h,
9880 bfd_vma offset)
9882 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9883 struct elf_link_hash_entry **search, *child;
9884 bfd_size_type extsymcount;
9885 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9887 /* The sh_info field of the symtab header tells us where the
9888 external symbols start. We don't care about the local symbols at
9889 this point. */
9890 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9891 if (!elf_bad_symtab (abfd))
9892 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9894 sym_hashes = elf_sym_hashes (abfd);
9895 sym_hashes_end = sym_hashes + extsymcount;
9897 /* Hunt down the child symbol, which is in this section at the same
9898 offset as the relocation. */
9899 for (search = sym_hashes; search != sym_hashes_end; ++search)
9901 if ((child = *search) != NULL
9902 && (child->root.type == bfd_link_hash_defined
9903 || child->root.type == bfd_link_hash_defweak)
9904 && child->root.u.def.section == sec
9905 && child->root.u.def.value == offset)
9906 goto win;
9909 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9910 abfd, sec, (unsigned long) offset);
9911 bfd_set_error (bfd_error_invalid_operation);
9912 return FALSE;
9914 win:
9915 if (!child->vtable)
9917 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9918 if (!child->vtable)
9919 return FALSE;
9921 if (!h)
9923 /* This *should* only be the absolute section. It could potentially
9924 be that someone has defined a non-global vtable though, which
9925 would be bad. It isn't worth paging in the local symbols to be
9926 sure though; that case should simply be handled by the assembler. */
9928 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9930 else
9931 child->vtable->parent = h;
9933 return TRUE;
9936 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9938 bfd_boolean
9939 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9940 asection *sec ATTRIBUTE_UNUSED,
9941 struct elf_link_hash_entry *h,
9942 bfd_vma addend)
9944 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9945 unsigned int log_file_align = bed->s->log_file_align;
9947 if (!h->vtable)
9949 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9950 if (!h->vtable)
9951 return FALSE;
9954 if (addend >= h->vtable->size)
9956 size_t size, bytes, file_align;
9957 bfd_boolean *ptr = h->vtable->used;
9959 /* While the symbol is undefined, we have to be prepared to handle
9960 a zero size. */
9961 file_align = 1 << log_file_align;
9962 if (h->root.type == bfd_link_hash_undefined)
9963 size = addend + file_align;
9964 else
9966 size = h->size;
9967 if (addend >= size)
9969 /* Oops! We've got a reference past the defined end of
9970 the table. This is probably a bug -- shall we warn? */
9971 size = addend + file_align;
9974 size = (size + file_align - 1) & -file_align;
9976 /* Allocate one extra entry for use as a "done" flag for the
9977 consolidation pass. */
9978 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9980 if (ptr)
9982 ptr = bfd_realloc (ptr - 1, bytes);
9984 if (ptr != NULL)
9986 size_t oldbytes;
9988 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9989 * sizeof (bfd_boolean));
9990 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9993 else
9994 ptr = bfd_zmalloc (bytes);
9996 if (ptr == NULL)
9997 return FALSE;
9999 /* And arrange for that done flag to be at index -1. */
10000 h->vtable->used = ptr + 1;
10001 h->vtable->size = size;
10004 h->vtable->used[addend >> log_file_align] = TRUE;
10006 return TRUE;
10009 struct alloc_got_off_arg {
10010 bfd_vma gotoff;
10011 unsigned int got_elt_size;
10014 /* We need a special top-level link routine to convert got reference counts
10015 to real got offsets. */
10017 static bfd_boolean
10018 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
10020 struct alloc_got_off_arg *gofarg = arg;
10022 if (h->root.type == bfd_link_hash_warning)
10023 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10025 if (h->got.refcount > 0)
10027 h->got.offset = gofarg->gotoff;
10028 gofarg->gotoff += gofarg->got_elt_size;
10030 else
10031 h->got.offset = (bfd_vma) -1;
10033 return TRUE;
10036 /* And an accompanying bit to work out final got entry offsets once
10037 we're done. Should be called from final_link. */
10039 bfd_boolean
10040 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
10041 struct bfd_link_info *info)
10043 bfd *i;
10044 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10045 bfd_vma gotoff;
10046 unsigned int got_elt_size = bed->s->arch_size / 8;
10047 struct alloc_got_off_arg gofarg;
10049 if (! is_elf_hash_table (info->hash))
10050 return FALSE;
10052 /* The GOT offset is relative to the .got section, but the GOT header is
10053 put into the .got.plt section, if the backend uses it. */
10054 if (bed->want_got_plt)
10055 gotoff = 0;
10056 else
10057 gotoff = bed->got_header_size;
10059 /* Do the local .got entries first. */
10060 for (i = info->input_bfds; i; i = i->link_next)
10062 bfd_signed_vma *local_got;
10063 bfd_size_type j, locsymcount;
10064 Elf_Internal_Shdr *symtab_hdr;
10066 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
10067 continue;
10069 local_got = elf_local_got_refcounts (i);
10070 if (!local_got)
10071 continue;
10073 symtab_hdr = &elf_tdata (i)->symtab_hdr;
10074 if (elf_bad_symtab (i))
10075 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
10076 else
10077 locsymcount = symtab_hdr->sh_info;
10079 for (j = 0; j < locsymcount; ++j)
10081 if (local_got[j] > 0)
10083 local_got[j] = gotoff;
10084 gotoff += got_elt_size;
10086 else
10087 local_got[j] = (bfd_vma) -1;
10091 /* Then the global .got entries. .plt refcounts are handled by
10092 adjust_dynamic_symbol */
10093 gofarg.gotoff = gotoff;
10094 gofarg.got_elt_size = got_elt_size;
10095 elf_link_hash_traverse (elf_hash_table (info),
10096 elf_gc_allocate_got_offsets,
10097 &gofarg);
10098 return TRUE;
10101 /* Many folk need no more in the way of final link than this, once
10102 got entry reference counting is enabled. */
10104 bfd_boolean
10105 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
10107 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
10108 return FALSE;
10110 /* Invoke the regular ELF backend linker to do all the work. */
10111 return bfd_elf_final_link (abfd, info);
10114 bfd_boolean
10115 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
10117 struct elf_reloc_cookie *rcookie = cookie;
10119 if (rcookie->bad_symtab)
10120 rcookie->rel = rcookie->rels;
10122 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
10124 unsigned long r_symndx;
10126 if (! rcookie->bad_symtab)
10127 if (rcookie->rel->r_offset > offset)
10128 return FALSE;
10129 if (rcookie->rel->r_offset != offset)
10130 continue;
10132 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
10133 if (r_symndx == SHN_UNDEF)
10134 return TRUE;
10136 if (r_symndx >= rcookie->locsymcount
10137 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
10139 struct elf_link_hash_entry *h;
10141 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
10143 while (h->root.type == bfd_link_hash_indirect
10144 || h->root.type == bfd_link_hash_warning)
10145 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10147 if ((h->root.type == bfd_link_hash_defined
10148 || h->root.type == bfd_link_hash_defweak)
10149 && elf_discarded_section (h->root.u.def.section))
10150 return TRUE;
10151 else
10152 return FALSE;
10154 else
10156 /* It's not a relocation against a global symbol,
10157 but it could be a relocation against a local
10158 symbol for a discarded section. */
10159 asection *isec;
10160 Elf_Internal_Sym *isym;
10162 /* Need to: get the symbol; get the section. */
10163 isym = &rcookie->locsyms[r_symndx];
10164 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
10166 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
10167 if (isec != NULL && elf_discarded_section (isec))
10168 return TRUE;
10171 return FALSE;
10173 return FALSE;
10176 /* Discard unneeded references to discarded sections.
10177 Returns TRUE if any section's size was changed. */
10178 /* This function assumes that the relocations are in sorted order,
10179 which is true for all known assemblers. */
10181 bfd_boolean
10182 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
10184 struct elf_reloc_cookie cookie;
10185 asection *stab, *eh;
10186 Elf_Internal_Shdr *symtab_hdr;
10187 const struct elf_backend_data *bed;
10188 bfd *abfd;
10189 unsigned int count;
10190 bfd_boolean ret = FALSE;
10192 if (info->traditional_format
10193 || !is_elf_hash_table (info->hash))
10194 return FALSE;
10196 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
10198 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
10199 continue;
10201 bed = get_elf_backend_data (abfd);
10203 if ((abfd->flags & DYNAMIC) != 0)
10204 continue;
10206 eh = bfd_get_section_by_name (abfd, ".eh_frame");
10207 if (info->relocatable
10208 || (eh != NULL
10209 && (eh->size == 0
10210 || bfd_is_abs_section (eh->output_section))))
10211 eh = NULL;
10213 stab = bfd_get_section_by_name (abfd, ".stab");
10214 if (stab != NULL
10215 && (stab->size == 0
10216 || bfd_is_abs_section (stab->output_section)
10217 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
10218 stab = NULL;
10220 if (stab == NULL
10221 && eh == NULL
10222 && bed->elf_backend_discard_info == NULL)
10223 continue;
10225 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
10226 cookie.abfd = abfd;
10227 cookie.sym_hashes = elf_sym_hashes (abfd);
10228 cookie.bad_symtab = elf_bad_symtab (abfd);
10229 if (cookie.bad_symtab)
10231 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
10232 cookie.extsymoff = 0;
10234 else
10236 cookie.locsymcount = symtab_hdr->sh_info;
10237 cookie.extsymoff = symtab_hdr->sh_info;
10240 if (bed->s->arch_size == 32)
10241 cookie.r_sym_shift = 8;
10242 else
10243 cookie.r_sym_shift = 32;
10245 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
10246 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
10248 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
10249 cookie.locsymcount, 0,
10250 NULL, NULL, NULL);
10251 if (cookie.locsyms == NULL)
10252 return FALSE;
10255 if (stab != NULL)
10257 cookie.rels = NULL;
10258 count = stab->reloc_count;
10259 if (count != 0)
10260 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
10261 info->keep_memory);
10262 if (cookie.rels != NULL)
10264 cookie.rel = cookie.rels;
10265 cookie.relend = cookie.rels;
10266 cookie.relend += count * bed->s->int_rels_per_ext_rel;
10267 if (_bfd_discard_section_stabs (abfd, stab,
10268 elf_section_data (stab)->sec_info,
10269 bfd_elf_reloc_symbol_deleted_p,
10270 &cookie))
10271 ret = TRUE;
10272 if (elf_section_data (stab)->relocs != cookie.rels)
10273 free (cookie.rels);
10277 if (eh != NULL)
10279 cookie.rels = NULL;
10280 count = eh->reloc_count;
10281 if (count != 0)
10282 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
10283 info->keep_memory);
10284 cookie.rel = cookie.rels;
10285 cookie.relend = cookie.rels;
10286 if (cookie.rels != NULL)
10287 cookie.relend += count * bed->s->int_rels_per_ext_rel;
10289 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
10290 bfd_elf_reloc_symbol_deleted_p,
10291 &cookie))
10292 ret = TRUE;
10294 if (cookie.rels != NULL
10295 && elf_section_data (eh)->relocs != cookie.rels)
10296 free (cookie.rels);
10299 if (bed->elf_backend_discard_info != NULL
10300 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
10301 ret = TRUE;
10303 if (cookie.locsyms != NULL
10304 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
10306 if (! info->keep_memory)
10307 free (cookie.locsyms);
10308 else
10309 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
10313 if (info->eh_frame_hdr
10314 && !info->relocatable
10315 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
10316 ret = TRUE;
10318 return ret;
10321 void
10322 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section *sec,
10323 struct bfd_link_info *info)
10325 flagword flags;
10326 const char *name, *p;
10327 struct bfd_section_already_linked *l;
10328 struct bfd_section_already_linked_hash_entry *already_linked_list;
10330 if (sec->output_section == bfd_abs_section_ptr)
10331 return;
10333 flags = sec->flags;
10335 /* Return if it isn't a linkonce section. A comdat group section
10336 also has SEC_LINK_ONCE set. */
10337 if ((flags & SEC_LINK_ONCE) == 0)
10338 return;
10340 /* Don't put group member sections on our list of already linked
10341 sections. They are handled as a group via their group section. */
10342 if (elf_sec_group (sec) != NULL)
10343 return;
10345 /* FIXME: When doing a relocatable link, we may have trouble
10346 copying relocations in other sections that refer to local symbols
10347 in the section being discarded. Those relocations will have to
10348 be converted somehow; as of this writing I'm not sure that any of
10349 the backends handle that correctly.
10351 It is tempting to instead not discard link once sections when
10352 doing a relocatable link (technically, they should be discarded
10353 whenever we are building constructors). However, that fails,
10354 because the linker winds up combining all the link once sections
10355 into a single large link once section, which defeats the purpose
10356 of having link once sections in the first place.
10358 Also, not merging link once sections in a relocatable link
10359 causes trouble for MIPS ELF, which relies on link once semantics
10360 to handle the .reginfo section correctly. */
10362 name = bfd_get_section_name (abfd, sec);
10364 if (CONST_STRNEQ (name, ".gnu.linkonce.")
10365 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
10366 p++;
10367 else
10368 p = name;
10370 already_linked_list = bfd_section_already_linked_table_lookup (p);
10372 for (l = already_linked_list->entry; l != NULL; l = l->next)
10374 /* We may have 2 different types of sections on the list: group
10375 sections and linkonce sections. Match like sections. */
10376 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
10377 && strcmp (name, l->sec->name) == 0
10378 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
10380 /* The section has already been linked. See if we should
10381 issue a warning. */
10382 switch (flags & SEC_LINK_DUPLICATES)
10384 default:
10385 abort ();
10387 case SEC_LINK_DUPLICATES_DISCARD:
10388 break;
10390 case SEC_LINK_DUPLICATES_ONE_ONLY:
10391 (*_bfd_error_handler)
10392 (_("%B: ignoring duplicate section `%A'"),
10393 abfd, sec);
10394 break;
10396 case SEC_LINK_DUPLICATES_SAME_SIZE:
10397 if (sec->size != l->sec->size)
10398 (*_bfd_error_handler)
10399 (_("%B: duplicate section `%A' has different size"),
10400 abfd, sec);
10401 break;
10403 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
10404 if (sec->size != l->sec->size)
10405 (*_bfd_error_handler)
10406 (_("%B: duplicate section `%A' has different size"),
10407 abfd, sec);
10408 else if (sec->size != 0)
10410 bfd_byte *sec_contents, *l_sec_contents;
10412 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
10413 (*_bfd_error_handler)
10414 (_("%B: warning: could not read contents of section `%A'"),
10415 abfd, sec);
10416 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
10417 &l_sec_contents))
10418 (*_bfd_error_handler)
10419 (_("%B: warning: could not read contents of section `%A'"),
10420 l->sec->owner, l->sec);
10421 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
10422 (*_bfd_error_handler)
10423 (_("%B: warning: duplicate section `%A' has different contents"),
10424 abfd, sec);
10426 if (sec_contents)
10427 free (sec_contents);
10428 if (l_sec_contents)
10429 free (l_sec_contents);
10431 break;
10434 /* Set the output_section field so that lang_add_section
10435 does not create a lang_input_section structure for this
10436 section. Since there might be a symbol in the section
10437 being discarded, we must retain a pointer to the section
10438 which we are really going to use. */
10439 sec->output_section = bfd_abs_section_ptr;
10440 sec->kept_section = l->sec;
10442 if (flags & SEC_GROUP)
10444 asection *first = elf_next_in_group (sec);
10445 asection *s = first;
10447 while (s != NULL)
10449 s->output_section = bfd_abs_section_ptr;
10450 /* Record which group discards it. */
10451 s->kept_section = l->sec;
10452 s = elf_next_in_group (s);
10453 /* These lists are circular. */
10454 if (s == first)
10455 break;
10459 return;
10463 /* A single member comdat group section may be discarded by a
10464 linkonce section and vice versa. */
10466 if ((flags & SEC_GROUP) != 0)
10468 asection *first = elf_next_in_group (sec);
10470 if (first != NULL && elf_next_in_group (first) == first)
10471 /* Check this single member group against linkonce sections. */
10472 for (l = already_linked_list->entry; l != NULL; l = l->next)
10473 if ((l->sec->flags & SEC_GROUP) == 0
10474 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
10475 && bfd_elf_match_symbols_in_sections (l->sec, first, info))
10477 first->output_section = bfd_abs_section_ptr;
10478 first->kept_section = l->sec;
10479 sec->output_section = bfd_abs_section_ptr;
10480 break;
10483 else
10484 /* Check this linkonce section against single member groups. */
10485 for (l = already_linked_list->entry; l != NULL; l = l->next)
10486 if (l->sec->flags & SEC_GROUP)
10488 asection *first = elf_next_in_group (l->sec);
10490 if (first != NULL
10491 && elf_next_in_group (first) == first
10492 && bfd_elf_match_symbols_in_sections (first, sec, info))
10494 sec->output_section = bfd_abs_section_ptr;
10495 sec->kept_section = first;
10496 break;
10500 /* This is the first section with this name. Record it. */
10501 bfd_section_already_linked_table_insert (already_linked_list, sec);
10504 bfd_boolean
10505 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
10507 return sym->st_shndx == SHN_COMMON;
10510 unsigned int
10511 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
10513 return SHN_COMMON;
10516 asection *
10517 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
10519 return bfd_com_section_ptr;