2005-02-08 Paul Brook <paul@codesourcery.com>
[binutils.git] / bfd / elflink.c
blobb8b9af5e2eef6a018d2749255f6fe39f80b56f12
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
3 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
30 bfd_boolean
31 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
33 flagword flags;
34 asection *s;
35 struct elf_link_hash_entry *h;
36 struct bfd_link_hash_entry *bh;
37 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
38 int ptralign;
40 /* This function may be called more than once. */
41 s = bfd_get_section_by_name (abfd, ".got");
42 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
43 return TRUE;
45 switch (bed->s->arch_size)
47 case 32:
48 ptralign = 2;
49 break;
51 case 64:
52 ptralign = 3;
53 break;
55 default:
56 bfd_set_error (bfd_error_bad_value);
57 return FALSE;
60 flags = bed->dynamic_sec_flags;
62 s = bfd_make_section (abfd, ".got");
63 if (s == NULL
64 || !bfd_set_section_flags (abfd, s, flags)
65 || !bfd_set_section_alignment (abfd, s, ptralign))
66 return FALSE;
68 if (bed->want_got_plt)
70 s = bfd_make_section (abfd, ".got.plt");
71 if (s == NULL
72 || !bfd_set_section_flags (abfd, s, flags)
73 || !bfd_set_section_alignment (abfd, s, ptralign))
74 return FALSE;
77 if (bed->want_got_sym)
79 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
80 (or .got.plt) section. We don't do this in the linker script
81 because we don't want to define the symbol if we are not creating
82 a global offset table. */
83 bh = NULL;
84 if (!(_bfd_generic_link_add_one_symbol
85 (info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s,
86 bed->got_symbol_offset, NULL, FALSE, bed->collect, &bh)))
87 return FALSE;
88 h = (struct elf_link_hash_entry *) bh;
89 h->def_regular = 1;
90 h->type = STT_OBJECT;
91 h->other = STV_HIDDEN;
93 if (! info->executable
94 && ! bfd_elf_link_record_dynamic_symbol (info, h))
95 return FALSE;
97 elf_hash_table (info)->hgot = h;
100 /* The first bit of the global offset table is the header. */
101 s->size += bed->got_header_size + bed->got_symbol_offset;
103 return TRUE;
106 /* Create a strtab to hold the dynamic symbol names. */
107 static bfd_boolean
108 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
110 struct elf_link_hash_table *hash_table;
112 hash_table = elf_hash_table (info);
113 if (hash_table->dynobj == NULL)
114 hash_table->dynobj = abfd;
116 if (hash_table->dynstr == NULL)
118 hash_table->dynstr = _bfd_elf_strtab_init ();
119 if (hash_table->dynstr == NULL)
120 return FALSE;
122 return TRUE;
125 /* Create some sections which will be filled in with dynamic linking
126 information. ABFD is an input file which requires dynamic sections
127 to be created. The dynamic sections take up virtual memory space
128 when the final executable is run, so we need to create them before
129 addresses are assigned to the output sections. We work out the
130 actual contents and size of these sections later. */
132 bfd_boolean
133 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
135 flagword flags;
136 register asection *s;
137 struct elf_link_hash_entry *h;
138 struct bfd_link_hash_entry *bh;
139 const struct elf_backend_data *bed;
141 if (! is_elf_hash_table (info->hash))
142 return FALSE;
144 if (elf_hash_table (info)->dynamic_sections_created)
145 return TRUE;
147 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
148 return FALSE;
150 abfd = elf_hash_table (info)->dynobj;
151 bed = get_elf_backend_data (abfd);
153 flags = bed->dynamic_sec_flags;
155 /* A dynamically linked executable has a .interp section, but a
156 shared library does not. */
157 if (info->executable)
159 s = bfd_make_section (abfd, ".interp");
160 if (s == NULL
161 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
162 return FALSE;
165 if (! info->traditional_format)
167 s = bfd_make_section (abfd, ".eh_frame_hdr");
168 if (s == NULL
169 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
170 || ! bfd_set_section_alignment (abfd, s, 2))
171 return FALSE;
172 elf_hash_table (info)->eh_info.hdr_sec = s;
175 /* Create sections to hold version informations. These are removed
176 if they are not needed. */
177 s = bfd_make_section (abfd, ".gnu.version_d");
178 if (s == NULL
179 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
180 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
181 return FALSE;
183 s = bfd_make_section (abfd, ".gnu.version");
184 if (s == NULL
185 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
186 || ! bfd_set_section_alignment (abfd, s, 1))
187 return FALSE;
189 s = bfd_make_section (abfd, ".gnu.version_r");
190 if (s == NULL
191 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
192 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
193 return FALSE;
195 s = bfd_make_section (abfd, ".dynsym");
196 if (s == NULL
197 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
198 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
199 return FALSE;
201 s = bfd_make_section (abfd, ".dynstr");
202 if (s == NULL
203 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
204 return FALSE;
206 s = bfd_make_section (abfd, ".dynamic");
207 if (s == NULL
208 || ! bfd_set_section_flags (abfd, s, flags)
209 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
210 return FALSE;
212 /* The special symbol _DYNAMIC is always set to the start of the
213 .dynamic section. We could set _DYNAMIC in a linker script, but we
214 only want to define it if we are, in fact, creating a .dynamic
215 section. We don't want to define it if there is no .dynamic
216 section, since on some ELF platforms the start up code examines it
217 to decide how to initialize the process. */
218 h = elf_link_hash_lookup (elf_hash_table (info), "_DYNAMIC",
219 FALSE, FALSE, FALSE);
220 if (h != NULL)
222 /* Zap symbol defined in an as-needed lib that wasn't linked.
223 This is a symptom of a larger problem: Absolute symbols
224 defined in shared libraries can't be overridden, because we
225 lose the link to the bfd which is via the symbol section. */
226 h->root.type = bfd_link_hash_new;
228 bh = &h->root;
229 if (! (_bfd_generic_link_add_one_symbol
230 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, 0, NULL, FALSE,
231 get_elf_backend_data (abfd)->collect, &bh)))
232 return FALSE;
233 h = (struct elf_link_hash_entry *) bh;
234 h->def_regular = 1;
235 h->type = STT_OBJECT;
237 if (! info->executable
238 && ! bfd_elf_link_record_dynamic_symbol (info, h))
239 return FALSE;
241 s = bfd_make_section (abfd, ".hash");
242 if (s == NULL
243 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
244 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
245 return FALSE;
246 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
248 /* Let the backend create the rest of the sections. This lets the
249 backend set the right flags. The backend will normally create
250 the .got and .plt sections. */
251 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
252 return FALSE;
254 elf_hash_table (info)->dynamic_sections_created = TRUE;
256 return TRUE;
259 /* Create dynamic sections when linking against a dynamic object. */
261 bfd_boolean
262 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
264 flagword flags, pltflags;
265 asection *s;
266 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
268 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
269 .rel[a].bss sections. */
270 flags = bed->dynamic_sec_flags;
272 pltflags = flags;
273 if (bed->plt_not_loaded)
274 /* We do not clear SEC_ALLOC here because we still want the OS to
275 allocate space for the section; it's just that there's nothing
276 to read in from the object file. */
277 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
278 else
279 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
280 if (bed->plt_readonly)
281 pltflags |= SEC_READONLY;
283 s = bfd_make_section (abfd, ".plt");
284 if (s == NULL
285 || ! bfd_set_section_flags (abfd, s, pltflags)
286 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
287 return FALSE;
289 if (bed->want_plt_sym)
291 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
292 .plt section. */
293 struct elf_link_hash_entry *h;
294 struct bfd_link_hash_entry *bh = NULL;
296 if (! (_bfd_generic_link_add_one_symbol
297 (info, abfd, "_PROCEDURE_LINKAGE_TABLE_", BSF_GLOBAL, s, 0, NULL,
298 FALSE, get_elf_backend_data (abfd)->collect, &bh)))
299 return FALSE;
300 h = (struct elf_link_hash_entry *) bh;
301 h->def_regular = 1;
302 h->type = STT_OBJECT;
304 if (! info->executable
305 && ! bfd_elf_link_record_dynamic_symbol (info, h))
306 return FALSE;
309 s = bfd_make_section (abfd,
310 bed->default_use_rela_p ? ".rela.plt" : ".rel.plt");
311 if (s == NULL
312 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
313 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
314 return FALSE;
316 if (! _bfd_elf_create_got_section (abfd, info))
317 return FALSE;
319 if (bed->want_dynbss)
321 /* The .dynbss section is a place to put symbols which are defined
322 by dynamic objects, are referenced by regular objects, and are
323 not functions. We must allocate space for them in the process
324 image and use a R_*_COPY reloc to tell the dynamic linker to
325 initialize them at run time. The linker script puts the .dynbss
326 section into the .bss section of the final image. */
327 s = bfd_make_section (abfd, ".dynbss");
328 if (s == NULL
329 || ! bfd_set_section_flags (abfd, s, SEC_ALLOC | SEC_LINKER_CREATED))
330 return FALSE;
332 /* The .rel[a].bss section holds copy relocs. This section is not
333 normally needed. We need to create it here, though, so that the
334 linker will map it to an output section. We can't just create it
335 only if we need it, because we will not know whether we need it
336 until we have seen all the input files, and the first time the
337 main linker code calls BFD after examining all the input files
338 (size_dynamic_sections) the input sections have already been
339 mapped to the output sections. If the section turns out not to
340 be needed, we can discard it later. We will never need this
341 section when generating a shared object, since they do not use
342 copy relocs. */
343 if (! info->shared)
345 s = bfd_make_section (abfd,
346 (bed->default_use_rela_p
347 ? ".rela.bss" : ".rel.bss"));
348 if (s == NULL
349 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
350 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
351 return FALSE;
355 return TRUE;
358 /* Record a new dynamic symbol. We record the dynamic symbols as we
359 read the input files, since we need to have a list of all of them
360 before we can determine the final sizes of the output sections.
361 Note that we may actually call this function even though we are not
362 going to output any dynamic symbols; in some cases we know that a
363 symbol should be in the dynamic symbol table, but only if there is
364 one. */
366 bfd_boolean
367 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
368 struct elf_link_hash_entry *h)
370 if (h->dynindx == -1)
372 struct elf_strtab_hash *dynstr;
373 char *p;
374 const char *name;
375 bfd_size_type indx;
377 /* XXX: The ABI draft says the linker must turn hidden and
378 internal symbols into STB_LOCAL symbols when producing the
379 DSO. However, if ld.so honors st_other in the dynamic table,
380 this would not be necessary. */
381 switch (ELF_ST_VISIBILITY (h->other))
383 case STV_INTERNAL:
384 case STV_HIDDEN:
385 if (h->root.type != bfd_link_hash_undefined
386 && h->root.type != bfd_link_hash_undefweak)
388 h->forced_local = 1;
389 return TRUE;
392 default:
393 break;
396 h->dynindx = elf_hash_table (info)->dynsymcount;
397 ++elf_hash_table (info)->dynsymcount;
399 dynstr = elf_hash_table (info)->dynstr;
400 if (dynstr == NULL)
402 /* Create a strtab to hold the dynamic symbol names. */
403 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
404 if (dynstr == NULL)
405 return FALSE;
408 /* We don't put any version information in the dynamic string
409 table. */
410 name = h->root.root.string;
411 p = strchr (name, ELF_VER_CHR);
412 if (p != NULL)
413 /* We know that the p points into writable memory. In fact,
414 there are only a few symbols that have read-only names, being
415 those like _GLOBAL_OFFSET_TABLE_ that are created specially
416 by the backends. Most symbols will have names pointing into
417 an ELF string table read from a file, or to objalloc memory. */
418 *p = 0;
420 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
422 if (p != NULL)
423 *p = ELF_VER_CHR;
425 if (indx == (bfd_size_type) -1)
426 return FALSE;
427 h->dynstr_index = indx;
430 return TRUE;
433 /* Record an assignment to a symbol made by a linker script. We need
434 this in case some dynamic object refers to this symbol. */
436 bfd_boolean
437 bfd_elf_record_link_assignment (bfd *output_bfd ATTRIBUTE_UNUSED,
438 struct bfd_link_info *info,
439 const char *name,
440 bfd_boolean provide)
442 struct elf_link_hash_entry *h;
443 struct elf_link_hash_table *htab;
445 if (!is_elf_hash_table (info->hash))
446 return TRUE;
448 htab = elf_hash_table (info);
449 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
450 if (h == NULL)
451 return provide;
453 /* Since we're defining the symbol, don't let it seem to have not
454 been defined. record_dynamic_symbol and size_dynamic_sections
455 may depend on this. */
456 if (h->root.type == bfd_link_hash_undefweak
457 || h->root.type == bfd_link_hash_undefined)
459 h->root.type = bfd_link_hash_new;
460 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
461 bfd_link_repair_undef_list (&htab->root);
464 if (h->root.type == bfd_link_hash_new)
465 h->non_elf = 0;
467 /* If this symbol is being provided by the linker script, and it is
468 currently defined by a dynamic object, but not by a regular
469 object, then mark it as undefined so that the generic linker will
470 force the correct value. */
471 if (provide
472 && h->def_dynamic
473 && !h->def_regular)
474 h->root.type = bfd_link_hash_undefined;
476 /* If this symbol is not being provided by the linker script, and it is
477 currently defined by a dynamic object, but not by a regular object,
478 then clear out any version information because the symbol will not be
479 associated with the dynamic object any more. */
480 if (!provide
481 && h->def_dynamic
482 && !h->def_regular)
483 h->verinfo.verdef = NULL;
485 h->def_regular = 1;
487 if ((h->def_dynamic
488 || h->ref_dynamic
489 || info->shared)
490 && h->dynindx == -1)
492 if (! bfd_elf_link_record_dynamic_symbol (info, h))
493 return FALSE;
495 /* If this is a weak defined symbol, and we know a corresponding
496 real symbol from the same dynamic object, make sure the real
497 symbol is also made into a dynamic symbol. */
498 if (h->u.weakdef != NULL
499 && h->u.weakdef->dynindx == -1)
501 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
502 return FALSE;
506 return TRUE;
509 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
510 success, and 2 on a failure caused by attempting to record a symbol
511 in a discarded section, eg. a discarded link-once section symbol. */
514 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
515 bfd *input_bfd,
516 long input_indx)
518 bfd_size_type amt;
519 struct elf_link_local_dynamic_entry *entry;
520 struct elf_link_hash_table *eht;
521 struct elf_strtab_hash *dynstr;
522 unsigned long dynstr_index;
523 char *name;
524 Elf_External_Sym_Shndx eshndx;
525 char esym[sizeof (Elf64_External_Sym)];
527 if (! is_elf_hash_table (info->hash))
528 return 0;
530 /* See if the entry exists already. */
531 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
532 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
533 return 1;
535 amt = sizeof (*entry);
536 entry = bfd_alloc (input_bfd, amt);
537 if (entry == NULL)
538 return 0;
540 /* Go find the symbol, so that we can find it's name. */
541 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
542 1, input_indx, &entry->isym, esym, &eshndx))
544 bfd_release (input_bfd, entry);
545 return 0;
548 if (entry->isym.st_shndx != SHN_UNDEF
549 && (entry->isym.st_shndx < SHN_LORESERVE
550 || entry->isym.st_shndx > SHN_HIRESERVE))
552 asection *s;
554 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
555 if (s == NULL || bfd_is_abs_section (s->output_section))
557 /* We can still bfd_release here as nothing has done another
558 bfd_alloc. We can't do this later in this function. */
559 bfd_release (input_bfd, entry);
560 return 2;
564 name = (bfd_elf_string_from_elf_section
565 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
566 entry->isym.st_name));
568 dynstr = elf_hash_table (info)->dynstr;
569 if (dynstr == NULL)
571 /* Create a strtab to hold the dynamic symbol names. */
572 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
573 if (dynstr == NULL)
574 return 0;
577 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
578 if (dynstr_index == (unsigned long) -1)
579 return 0;
580 entry->isym.st_name = dynstr_index;
582 eht = elf_hash_table (info);
584 entry->next = eht->dynlocal;
585 eht->dynlocal = entry;
586 entry->input_bfd = input_bfd;
587 entry->input_indx = input_indx;
588 eht->dynsymcount++;
590 /* Whatever binding the symbol had before, it's now local. */
591 entry->isym.st_info
592 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
594 /* The dynindx will be set at the end of size_dynamic_sections. */
596 return 1;
599 /* Return the dynindex of a local dynamic symbol. */
601 long
602 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
603 bfd *input_bfd,
604 long input_indx)
606 struct elf_link_local_dynamic_entry *e;
608 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
609 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
610 return e->dynindx;
611 return -1;
614 /* This function is used to renumber the dynamic symbols, if some of
615 them are removed because they are marked as local. This is called
616 via elf_link_hash_traverse. */
618 static bfd_boolean
619 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
620 void *data)
622 size_t *count = data;
624 if (h->root.type == bfd_link_hash_warning)
625 h = (struct elf_link_hash_entry *) h->root.u.i.link;
627 if (h->dynindx != -1)
628 h->dynindx = ++(*count);
630 return TRUE;
633 /* Return true if the dynamic symbol for a given section should be
634 omitted when creating a shared library. */
635 bfd_boolean
636 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
637 struct bfd_link_info *info,
638 asection *p)
640 switch (elf_section_data (p)->this_hdr.sh_type)
642 case SHT_PROGBITS:
643 case SHT_NOBITS:
644 /* If sh_type is yet undecided, assume it could be
645 SHT_PROGBITS/SHT_NOBITS. */
646 case SHT_NULL:
647 if (strcmp (p->name, ".got") == 0
648 || strcmp (p->name, ".got.plt") == 0
649 || strcmp (p->name, ".plt") == 0)
651 asection *ip;
652 bfd *dynobj = elf_hash_table (info)->dynobj;
654 if (dynobj != NULL
655 && (ip = bfd_get_section_by_name (dynobj, p->name)) != NULL
656 && (ip->flags & SEC_LINKER_CREATED)
657 && ip->output_section == p)
658 return TRUE;
660 return FALSE;
662 /* There shouldn't be section relative relocations
663 against any other section. */
664 default:
665 return TRUE;
669 /* Assign dynsym indices. In a shared library we generate a section
670 symbol for each output section, which come first. Next come all of
671 the back-end allocated local dynamic syms, followed by the rest of
672 the global symbols. */
674 unsigned long
675 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd, struct bfd_link_info *info)
677 unsigned long dynsymcount = 0;
679 if (info->shared)
681 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
682 asection *p;
683 for (p = output_bfd->sections; p ; p = p->next)
684 if ((p->flags & SEC_EXCLUDE) == 0
685 && (p->flags & SEC_ALLOC) != 0
686 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
687 elf_section_data (p)->dynindx = ++dynsymcount;
690 if (elf_hash_table (info)->dynlocal)
692 struct elf_link_local_dynamic_entry *p;
693 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
694 p->dynindx = ++dynsymcount;
697 elf_link_hash_traverse (elf_hash_table (info),
698 elf_link_renumber_hash_table_dynsyms,
699 &dynsymcount);
701 /* There is an unused NULL entry at the head of the table which
702 we must account for in our count. Unless there weren't any
703 symbols, which means we'll have no table at all. */
704 if (dynsymcount != 0)
705 ++dynsymcount;
707 return elf_hash_table (info)->dynsymcount = dynsymcount;
710 /* This function is called when we want to define a new symbol. It
711 handles the various cases which arise when we find a definition in
712 a dynamic object, or when there is already a definition in a
713 dynamic object. The new symbol is described by NAME, SYM, PSEC,
714 and PVALUE. We set SYM_HASH to the hash table entry. We set
715 OVERRIDE if the old symbol is overriding a new definition. We set
716 TYPE_CHANGE_OK if it is OK for the type to change. We set
717 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
718 change, we mean that we shouldn't warn if the type or size does
719 change. */
721 bfd_boolean
722 _bfd_elf_merge_symbol (bfd *abfd,
723 struct bfd_link_info *info,
724 const char *name,
725 Elf_Internal_Sym *sym,
726 asection **psec,
727 bfd_vma *pvalue,
728 struct elf_link_hash_entry **sym_hash,
729 bfd_boolean *skip,
730 bfd_boolean *override,
731 bfd_boolean *type_change_ok,
732 bfd_boolean *size_change_ok)
734 asection *sec, *oldsec;
735 struct elf_link_hash_entry *h;
736 struct elf_link_hash_entry *flip;
737 int bind;
738 bfd *oldbfd;
739 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
740 bfd_boolean newweak, oldweak;
742 *skip = FALSE;
743 *override = FALSE;
745 sec = *psec;
746 bind = ELF_ST_BIND (sym->st_info);
748 if (! bfd_is_und_section (sec))
749 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
750 else
751 h = ((struct elf_link_hash_entry *)
752 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
753 if (h == NULL)
754 return FALSE;
755 *sym_hash = h;
757 /* This code is for coping with dynamic objects, and is only useful
758 if we are doing an ELF link. */
759 if (info->hash->creator != abfd->xvec)
760 return TRUE;
762 /* For merging, we only care about real symbols. */
764 while (h->root.type == bfd_link_hash_indirect
765 || h->root.type == bfd_link_hash_warning)
766 h = (struct elf_link_hash_entry *) h->root.u.i.link;
768 /* If we just created the symbol, mark it as being an ELF symbol.
769 Other than that, there is nothing to do--there is no merge issue
770 with a newly defined symbol--so we just return. */
772 if (h->root.type == bfd_link_hash_new)
774 h->non_elf = 0;
775 return TRUE;
778 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
779 existing symbol. */
781 switch (h->root.type)
783 default:
784 oldbfd = NULL;
785 oldsec = NULL;
786 break;
788 case bfd_link_hash_undefined:
789 case bfd_link_hash_undefweak:
790 oldbfd = h->root.u.undef.abfd;
791 oldsec = NULL;
792 break;
794 case bfd_link_hash_defined:
795 case bfd_link_hash_defweak:
796 oldbfd = h->root.u.def.section->owner;
797 oldsec = h->root.u.def.section;
798 break;
800 case bfd_link_hash_common:
801 oldbfd = h->root.u.c.p->section->owner;
802 oldsec = h->root.u.c.p->section;
803 break;
806 /* In cases involving weak versioned symbols, we may wind up trying
807 to merge a symbol with itself. Catch that here, to avoid the
808 confusion that results if we try to override a symbol with
809 itself. The additional tests catch cases like
810 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
811 dynamic object, which we do want to handle here. */
812 if (abfd == oldbfd
813 && ((abfd->flags & DYNAMIC) == 0
814 || !h->def_regular))
815 return TRUE;
817 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
818 respectively, is from a dynamic object. */
820 if ((abfd->flags & DYNAMIC) != 0)
821 newdyn = TRUE;
822 else
823 newdyn = FALSE;
825 if (oldbfd != NULL)
826 olddyn = (oldbfd->flags & DYNAMIC) != 0;
827 else
829 asection *hsec;
831 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
832 indices used by MIPS ELF. */
833 switch (h->root.type)
835 default:
836 hsec = NULL;
837 break;
839 case bfd_link_hash_defined:
840 case bfd_link_hash_defweak:
841 hsec = h->root.u.def.section;
842 break;
844 case bfd_link_hash_common:
845 hsec = h->root.u.c.p->section;
846 break;
849 if (hsec == NULL)
850 olddyn = FALSE;
851 else
852 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
855 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
856 respectively, appear to be a definition rather than reference. */
858 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
859 newdef = FALSE;
860 else
861 newdef = TRUE;
863 if (h->root.type == bfd_link_hash_undefined
864 || h->root.type == bfd_link_hash_undefweak
865 || h->root.type == bfd_link_hash_common)
866 olddef = FALSE;
867 else
868 olddef = TRUE;
870 /* Check TLS symbol. */
871 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
872 && ELF_ST_TYPE (sym->st_info) != h->type)
874 bfd *ntbfd, *tbfd;
875 bfd_boolean ntdef, tdef;
876 asection *ntsec, *tsec;
878 if (h->type == STT_TLS)
880 ntbfd = abfd;
881 ntsec = sec;
882 ntdef = newdef;
883 tbfd = oldbfd;
884 tsec = oldsec;
885 tdef = olddef;
887 else
889 ntbfd = oldbfd;
890 ntsec = oldsec;
891 ntdef = olddef;
892 tbfd = abfd;
893 tsec = sec;
894 tdef = newdef;
897 if (tdef && ntdef)
898 (*_bfd_error_handler)
899 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
900 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
901 else if (!tdef && !ntdef)
902 (*_bfd_error_handler)
903 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
904 tbfd, ntbfd, h->root.root.string);
905 else if (tdef)
906 (*_bfd_error_handler)
907 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
908 tbfd, tsec, ntbfd, h->root.root.string);
909 else
910 (*_bfd_error_handler)
911 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
912 tbfd, ntbfd, ntsec, h->root.root.string);
914 bfd_set_error (bfd_error_bad_value);
915 return FALSE;
918 /* We need to remember if a symbol has a definition in a dynamic
919 object or is weak in all dynamic objects. Internal and hidden
920 visibility will make it unavailable to dynamic objects. */
921 if (newdyn && !h->dynamic_def)
923 if (!bfd_is_und_section (sec))
924 h->dynamic_def = 1;
925 else
927 /* Check if this symbol is weak in all dynamic objects. If it
928 is the first time we see it in a dynamic object, we mark
929 if it is weak. Otherwise, we clear it. */
930 if (!h->ref_dynamic)
932 if (bind == STB_WEAK)
933 h->dynamic_weak = 1;
935 else if (bind != STB_WEAK)
936 h->dynamic_weak = 0;
940 /* If the old symbol has non-default visibility, we ignore the new
941 definition from a dynamic object. */
942 if (newdyn
943 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
944 && !bfd_is_und_section (sec))
946 *skip = TRUE;
947 /* Make sure this symbol is dynamic. */
948 h->ref_dynamic = 1;
949 /* A protected symbol has external availability. Make sure it is
950 recorded as dynamic.
952 FIXME: Should we check type and size for protected symbol? */
953 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
954 return bfd_elf_link_record_dynamic_symbol (info, h);
955 else
956 return TRUE;
958 else if (!newdyn
959 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
960 && h->def_dynamic)
962 /* If the new symbol with non-default visibility comes from a
963 relocatable file and the old definition comes from a dynamic
964 object, we remove the old definition. */
965 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
966 h = *sym_hash;
968 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
969 && bfd_is_und_section (sec))
971 /* If the new symbol is undefined and the old symbol was
972 also undefined before, we need to make sure
973 _bfd_generic_link_add_one_symbol doesn't mess
974 up the linker hash table undefs list. Since the old
975 definition came from a dynamic object, it is still on the
976 undefs list. */
977 h->root.type = bfd_link_hash_undefined;
978 h->root.u.undef.abfd = abfd;
980 else
982 h->root.type = bfd_link_hash_new;
983 h->root.u.undef.abfd = NULL;
986 if (h->def_dynamic)
988 h->def_dynamic = 0;
989 h->ref_dynamic = 1;
990 h->dynamic_def = 1;
992 /* FIXME: Should we check type and size for protected symbol? */
993 h->size = 0;
994 h->type = 0;
995 return TRUE;
998 /* Differentiate strong and weak symbols. */
999 newweak = bind == STB_WEAK;
1000 oldweak = (h->root.type == bfd_link_hash_defweak
1001 || h->root.type == bfd_link_hash_undefweak);
1003 /* If a new weak symbol definition comes from a regular file and the
1004 old symbol comes from a dynamic library, we treat the new one as
1005 strong. Similarly, an old weak symbol definition from a regular
1006 file is treated as strong when the new symbol comes from a dynamic
1007 library. Further, an old weak symbol from a dynamic library is
1008 treated as strong if the new symbol is from a dynamic library.
1009 This reflects the way glibc's ld.so works.
1011 Do this before setting *type_change_ok or *size_change_ok so that
1012 we warn properly when dynamic library symbols are overridden. */
1014 if (newdef && !newdyn && olddyn)
1015 newweak = FALSE;
1016 if (olddef && newdyn)
1017 oldweak = FALSE;
1019 /* It's OK to change the type if either the existing symbol or the
1020 new symbol is weak. A type change is also OK if the old symbol
1021 is undefined and the new symbol is defined. */
1023 if (oldweak
1024 || newweak
1025 || (newdef
1026 && h->root.type == bfd_link_hash_undefined))
1027 *type_change_ok = TRUE;
1029 /* It's OK to change the size if either the existing symbol or the
1030 new symbol is weak, or if the old symbol is undefined. */
1032 if (*type_change_ok
1033 || h->root.type == bfd_link_hash_undefined)
1034 *size_change_ok = TRUE;
1036 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1037 symbol, respectively, appears to be a common symbol in a dynamic
1038 object. If a symbol appears in an uninitialized section, and is
1039 not weak, and is not a function, then it may be a common symbol
1040 which was resolved when the dynamic object was created. We want
1041 to treat such symbols specially, because they raise special
1042 considerations when setting the symbol size: if the symbol
1043 appears as a common symbol in a regular object, and the size in
1044 the regular object is larger, we must make sure that we use the
1045 larger size. This problematic case can always be avoided in C,
1046 but it must be handled correctly when using Fortran shared
1047 libraries.
1049 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1050 likewise for OLDDYNCOMMON and OLDDEF.
1052 Note that this test is just a heuristic, and that it is quite
1053 possible to have an uninitialized symbol in a shared object which
1054 is really a definition, rather than a common symbol. This could
1055 lead to some minor confusion when the symbol really is a common
1056 symbol in some regular object. However, I think it will be
1057 harmless. */
1059 if (newdyn
1060 && newdef
1061 && !newweak
1062 && (sec->flags & SEC_ALLOC) != 0
1063 && (sec->flags & SEC_LOAD) == 0
1064 && sym->st_size > 0
1065 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1066 newdyncommon = TRUE;
1067 else
1068 newdyncommon = FALSE;
1070 if (olddyn
1071 && olddef
1072 && h->root.type == bfd_link_hash_defined
1073 && h->def_dynamic
1074 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1075 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1076 && h->size > 0
1077 && h->type != STT_FUNC)
1078 olddyncommon = TRUE;
1079 else
1080 olddyncommon = FALSE;
1082 /* If both the old and the new symbols look like common symbols in a
1083 dynamic object, set the size of the symbol to the larger of the
1084 two. */
1086 if (olddyncommon
1087 && newdyncommon
1088 && sym->st_size != h->size)
1090 /* Since we think we have two common symbols, issue a multiple
1091 common warning if desired. Note that we only warn if the
1092 size is different. If the size is the same, we simply let
1093 the old symbol override the new one as normally happens with
1094 symbols defined in dynamic objects. */
1096 if (! ((*info->callbacks->multiple_common)
1097 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1098 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1099 return FALSE;
1101 if (sym->st_size > h->size)
1102 h->size = sym->st_size;
1104 *size_change_ok = TRUE;
1107 /* If we are looking at a dynamic object, and we have found a
1108 definition, we need to see if the symbol was already defined by
1109 some other object. If so, we want to use the existing
1110 definition, and we do not want to report a multiple symbol
1111 definition error; we do this by clobbering *PSEC to be
1112 bfd_und_section_ptr.
1114 We treat a common symbol as a definition if the symbol in the
1115 shared library is a function, since common symbols always
1116 represent variables; this can cause confusion in principle, but
1117 any such confusion would seem to indicate an erroneous program or
1118 shared library. We also permit a common symbol in a regular
1119 object to override a weak symbol in a shared object. */
1121 if (newdyn
1122 && newdef
1123 && (olddef
1124 || (h->root.type == bfd_link_hash_common
1125 && (newweak
1126 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1128 *override = TRUE;
1129 newdef = FALSE;
1130 newdyncommon = FALSE;
1132 *psec = sec = bfd_und_section_ptr;
1133 *size_change_ok = TRUE;
1135 /* If we get here when the old symbol is a common symbol, then
1136 we are explicitly letting it override a weak symbol or
1137 function in a dynamic object, and we don't want to warn about
1138 a type change. If the old symbol is a defined symbol, a type
1139 change warning may still be appropriate. */
1141 if (h->root.type == bfd_link_hash_common)
1142 *type_change_ok = TRUE;
1145 /* Handle the special case of an old common symbol merging with a
1146 new symbol which looks like a common symbol in a shared object.
1147 We change *PSEC and *PVALUE to make the new symbol look like a
1148 common symbol, and let _bfd_generic_link_add_one_symbol will do
1149 the right thing. */
1151 if (newdyncommon
1152 && h->root.type == bfd_link_hash_common)
1154 *override = TRUE;
1155 newdef = FALSE;
1156 newdyncommon = FALSE;
1157 *pvalue = sym->st_size;
1158 *psec = sec = bfd_com_section_ptr;
1159 *size_change_ok = TRUE;
1162 /* If the old symbol is from a dynamic object, and the new symbol is
1163 a definition which is not from a dynamic object, then the new
1164 symbol overrides the old symbol. Symbols from regular files
1165 always take precedence over symbols from dynamic objects, even if
1166 they are defined after the dynamic object in the link.
1168 As above, we again permit a common symbol in a regular object to
1169 override a definition in a shared object if the shared object
1170 symbol is a function or is weak. */
1172 flip = NULL;
1173 if (!newdyn
1174 && (newdef
1175 || (bfd_is_com_section (sec)
1176 && (oldweak
1177 || h->type == STT_FUNC)))
1178 && olddyn
1179 && olddef
1180 && h->def_dynamic)
1182 /* Change the hash table entry to undefined, and let
1183 _bfd_generic_link_add_one_symbol do the right thing with the
1184 new definition. */
1186 h->root.type = bfd_link_hash_undefined;
1187 h->root.u.undef.abfd = h->root.u.def.section->owner;
1188 *size_change_ok = TRUE;
1190 olddef = FALSE;
1191 olddyncommon = FALSE;
1193 /* We again permit a type change when a common symbol may be
1194 overriding a function. */
1196 if (bfd_is_com_section (sec))
1197 *type_change_ok = TRUE;
1199 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1200 flip = *sym_hash;
1201 else
1202 /* This union may have been set to be non-NULL when this symbol
1203 was seen in a dynamic object. We must force the union to be
1204 NULL, so that it is correct for a regular symbol. */
1205 h->verinfo.vertree = NULL;
1208 /* Handle the special case of a new common symbol merging with an
1209 old symbol that looks like it might be a common symbol defined in
1210 a shared object. Note that we have already handled the case in
1211 which a new common symbol should simply override the definition
1212 in the shared library. */
1214 if (! newdyn
1215 && bfd_is_com_section (sec)
1216 && olddyncommon)
1218 /* It would be best if we could set the hash table entry to a
1219 common symbol, but we don't know what to use for the section
1220 or the alignment. */
1221 if (! ((*info->callbacks->multiple_common)
1222 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1223 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1224 return FALSE;
1226 /* If the presumed common symbol in the dynamic object is
1227 larger, pretend that the new symbol has its size. */
1229 if (h->size > *pvalue)
1230 *pvalue = h->size;
1232 /* FIXME: We no longer know the alignment required by the symbol
1233 in the dynamic object, so we just wind up using the one from
1234 the regular object. */
1236 olddef = FALSE;
1237 olddyncommon = FALSE;
1239 h->root.type = bfd_link_hash_undefined;
1240 h->root.u.undef.abfd = h->root.u.def.section->owner;
1242 *size_change_ok = TRUE;
1243 *type_change_ok = TRUE;
1245 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1246 flip = *sym_hash;
1247 else
1248 h->verinfo.vertree = NULL;
1251 if (flip != NULL)
1253 /* Handle the case where we had a versioned symbol in a dynamic
1254 library and now find a definition in a normal object. In this
1255 case, we make the versioned symbol point to the normal one. */
1256 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1257 flip->root.type = h->root.type;
1258 h->root.type = bfd_link_hash_indirect;
1259 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1260 (*bed->elf_backend_copy_indirect_symbol) (bed, flip, h);
1261 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1262 if (h->def_dynamic)
1264 h->def_dynamic = 0;
1265 flip->ref_dynamic = 1;
1269 return TRUE;
1272 /* This function is called to create an indirect symbol from the
1273 default for the symbol with the default version if needed. The
1274 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1275 set DYNSYM if the new indirect symbol is dynamic. */
1277 bfd_boolean
1278 _bfd_elf_add_default_symbol (bfd *abfd,
1279 struct bfd_link_info *info,
1280 struct elf_link_hash_entry *h,
1281 const char *name,
1282 Elf_Internal_Sym *sym,
1283 asection **psec,
1284 bfd_vma *value,
1285 bfd_boolean *dynsym,
1286 bfd_boolean override)
1288 bfd_boolean type_change_ok;
1289 bfd_boolean size_change_ok;
1290 bfd_boolean skip;
1291 char *shortname;
1292 struct elf_link_hash_entry *hi;
1293 struct bfd_link_hash_entry *bh;
1294 const struct elf_backend_data *bed;
1295 bfd_boolean collect;
1296 bfd_boolean dynamic;
1297 char *p;
1298 size_t len, shortlen;
1299 asection *sec;
1301 /* If this symbol has a version, and it is the default version, we
1302 create an indirect symbol from the default name to the fully
1303 decorated name. This will cause external references which do not
1304 specify a version to be bound to this version of the symbol. */
1305 p = strchr (name, ELF_VER_CHR);
1306 if (p == NULL || p[1] != ELF_VER_CHR)
1307 return TRUE;
1309 if (override)
1311 /* We are overridden by an old definition. We need to check if we
1312 need to create the indirect symbol from the default name. */
1313 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1314 FALSE, FALSE);
1315 BFD_ASSERT (hi != NULL);
1316 if (hi == h)
1317 return TRUE;
1318 while (hi->root.type == bfd_link_hash_indirect
1319 || hi->root.type == bfd_link_hash_warning)
1321 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1322 if (hi == h)
1323 return TRUE;
1327 bed = get_elf_backend_data (abfd);
1328 collect = bed->collect;
1329 dynamic = (abfd->flags & DYNAMIC) != 0;
1331 shortlen = p - name;
1332 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1333 if (shortname == NULL)
1334 return FALSE;
1335 memcpy (shortname, name, shortlen);
1336 shortname[shortlen] = '\0';
1338 /* We are going to create a new symbol. Merge it with any existing
1339 symbol with this name. For the purposes of the merge, act as
1340 though we were defining the symbol we just defined, although we
1341 actually going to define an indirect symbol. */
1342 type_change_ok = FALSE;
1343 size_change_ok = FALSE;
1344 sec = *psec;
1345 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1346 &hi, &skip, &override, &type_change_ok,
1347 &size_change_ok))
1348 return FALSE;
1350 if (skip)
1351 goto nondefault;
1353 if (! override)
1355 bh = &hi->root;
1356 if (! (_bfd_generic_link_add_one_symbol
1357 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1358 0, name, FALSE, collect, &bh)))
1359 return FALSE;
1360 hi = (struct elf_link_hash_entry *) bh;
1362 else
1364 /* In this case the symbol named SHORTNAME is overriding the
1365 indirect symbol we want to add. We were planning on making
1366 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1367 is the name without a version. NAME is the fully versioned
1368 name, and it is the default version.
1370 Overriding means that we already saw a definition for the
1371 symbol SHORTNAME in a regular object, and it is overriding
1372 the symbol defined in the dynamic object.
1374 When this happens, we actually want to change NAME, the
1375 symbol we just added, to refer to SHORTNAME. This will cause
1376 references to NAME in the shared object to become references
1377 to SHORTNAME in the regular object. This is what we expect
1378 when we override a function in a shared object: that the
1379 references in the shared object will be mapped to the
1380 definition in the regular object. */
1382 while (hi->root.type == bfd_link_hash_indirect
1383 || hi->root.type == bfd_link_hash_warning)
1384 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1386 h->root.type = bfd_link_hash_indirect;
1387 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1388 if (h->def_dynamic)
1390 h->def_dynamic = 0;
1391 hi->ref_dynamic = 1;
1392 if (hi->ref_regular
1393 || hi->def_regular)
1395 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1396 return FALSE;
1400 /* Now set HI to H, so that the following code will set the
1401 other fields correctly. */
1402 hi = h;
1405 /* If there is a duplicate definition somewhere, then HI may not
1406 point to an indirect symbol. We will have reported an error to
1407 the user in that case. */
1409 if (hi->root.type == bfd_link_hash_indirect)
1411 struct elf_link_hash_entry *ht;
1413 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1414 (*bed->elf_backend_copy_indirect_symbol) (bed, ht, hi);
1416 /* See if the new flags lead us to realize that the symbol must
1417 be dynamic. */
1418 if (! *dynsym)
1420 if (! dynamic)
1422 if (info->shared
1423 || hi->ref_dynamic)
1424 *dynsym = TRUE;
1426 else
1428 if (hi->ref_regular)
1429 *dynsym = TRUE;
1434 /* We also need to define an indirection from the nondefault version
1435 of the symbol. */
1437 nondefault:
1438 len = strlen (name);
1439 shortname = bfd_hash_allocate (&info->hash->table, len);
1440 if (shortname == NULL)
1441 return FALSE;
1442 memcpy (shortname, name, shortlen);
1443 memcpy (shortname + shortlen, p + 1, len - shortlen);
1445 /* Once again, merge with any existing symbol. */
1446 type_change_ok = FALSE;
1447 size_change_ok = FALSE;
1448 sec = *psec;
1449 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1450 &hi, &skip, &override, &type_change_ok,
1451 &size_change_ok))
1452 return FALSE;
1454 if (skip)
1455 return TRUE;
1457 if (override)
1459 /* Here SHORTNAME is a versioned name, so we don't expect to see
1460 the type of override we do in the case above unless it is
1461 overridden by a versioned definition. */
1462 if (hi->root.type != bfd_link_hash_defined
1463 && hi->root.type != bfd_link_hash_defweak)
1464 (*_bfd_error_handler)
1465 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1466 abfd, shortname);
1468 else
1470 bh = &hi->root;
1471 if (! (_bfd_generic_link_add_one_symbol
1472 (info, abfd, shortname, BSF_INDIRECT,
1473 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1474 return FALSE;
1475 hi = (struct elf_link_hash_entry *) bh;
1477 /* If there is a duplicate definition somewhere, then HI may not
1478 point to an indirect symbol. We will have reported an error
1479 to the user in that case. */
1481 if (hi->root.type == bfd_link_hash_indirect)
1483 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
1485 /* See if the new flags lead us to realize that the symbol
1486 must be dynamic. */
1487 if (! *dynsym)
1489 if (! dynamic)
1491 if (info->shared
1492 || hi->ref_dynamic)
1493 *dynsym = TRUE;
1495 else
1497 if (hi->ref_regular)
1498 *dynsym = TRUE;
1504 return TRUE;
1507 /* This routine is used to export all defined symbols into the dynamic
1508 symbol table. It is called via elf_link_hash_traverse. */
1510 bfd_boolean
1511 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1513 struct elf_info_failed *eif = data;
1515 /* Ignore indirect symbols. These are added by the versioning code. */
1516 if (h->root.type == bfd_link_hash_indirect)
1517 return TRUE;
1519 if (h->root.type == bfd_link_hash_warning)
1520 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1522 if (h->dynindx == -1
1523 && (h->def_regular
1524 || h->ref_regular))
1526 struct bfd_elf_version_tree *t;
1527 struct bfd_elf_version_expr *d;
1529 for (t = eif->verdefs; t != NULL; t = t->next)
1531 if (t->globals.list != NULL)
1533 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1534 if (d != NULL)
1535 goto doit;
1538 if (t->locals.list != NULL)
1540 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1541 if (d != NULL)
1542 return TRUE;
1546 if (!eif->verdefs)
1548 doit:
1549 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1551 eif->failed = TRUE;
1552 return FALSE;
1557 return TRUE;
1560 /* Look through the symbols which are defined in other shared
1561 libraries and referenced here. Update the list of version
1562 dependencies. This will be put into the .gnu.version_r section.
1563 This function is called via elf_link_hash_traverse. */
1565 bfd_boolean
1566 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1567 void *data)
1569 struct elf_find_verdep_info *rinfo = data;
1570 Elf_Internal_Verneed *t;
1571 Elf_Internal_Vernaux *a;
1572 bfd_size_type amt;
1574 if (h->root.type == bfd_link_hash_warning)
1575 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1577 /* We only care about symbols defined in shared objects with version
1578 information. */
1579 if (!h->def_dynamic
1580 || h->def_regular
1581 || h->dynindx == -1
1582 || h->verinfo.verdef == NULL)
1583 return TRUE;
1585 /* See if we already know about this version. */
1586 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1588 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1589 continue;
1591 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1592 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1593 return TRUE;
1595 break;
1598 /* This is a new version. Add it to tree we are building. */
1600 if (t == NULL)
1602 amt = sizeof *t;
1603 t = bfd_zalloc (rinfo->output_bfd, amt);
1604 if (t == NULL)
1606 rinfo->failed = TRUE;
1607 return FALSE;
1610 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1611 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1612 elf_tdata (rinfo->output_bfd)->verref = t;
1615 amt = sizeof *a;
1616 a = bfd_zalloc (rinfo->output_bfd, amt);
1618 /* Note that we are copying a string pointer here, and testing it
1619 above. If bfd_elf_string_from_elf_section is ever changed to
1620 discard the string data when low in memory, this will have to be
1621 fixed. */
1622 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1624 a->vna_flags = h->verinfo.verdef->vd_flags;
1625 a->vna_nextptr = t->vn_auxptr;
1627 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1628 ++rinfo->vers;
1630 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1632 t->vn_auxptr = a;
1634 return TRUE;
1637 /* Figure out appropriate versions for all the symbols. We may not
1638 have the version number script until we have read all of the input
1639 files, so until that point we don't know which symbols should be
1640 local. This function is called via elf_link_hash_traverse. */
1642 bfd_boolean
1643 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1645 struct elf_assign_sym_version_info *sinfo;
1646 struct bfd_link_info *info;
1647 const struct elf_backend_data *bed;
1648 struct elf_info_failed eif;
1649 char *p;
1650 bfd_size_type amt;
1652 sinfo = data;
1653 info = sinfo->info;
1655 if (h->root.type == bfd_link_hash_warning)
1656 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1658 /* Fix the symbol flags. */
1659 eif.failed = FALSE;
1660 eif.info = info;
1661 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1663 if (eif.failed)
1664 sinfo->failed = TRUE;
1665 return FALSE;
1668 /* We only need version numbers for symbols defined in regular
1669 objects. */
1670 if (!h->def_regular)
1671 return TRUE;
1673 bed = get_elf_backend_data (sinfo->output_bfd);
1674 p = strchr (h->root.root.string, ELF_VER_CHR);
1675 if (p != NULL && h->verinfo.vertree == NULL)
1677 struct bfd_elf_version_tree *t;
1678 bfd_boolean hidden;
1680 hidden = TRUE;
1682 /* There are two consecutive ELF_VER_CHR characters if this is
1683 not a hidden symbol. */
1684 ++p;
1685 if (*p == ELF_VER_CHR)
1687 hidden = FALSE;
1688 ++p;
1691 /* If there is no version string, we can just return out. */
1692 if (*p == '\0')
1694 if (hidden)
1695 h->hidden = 1;
1696 return TRUE;
1699 /* Look for the version. If we find it, it is no longer weak. */
1700 for (t = sinfo->verdefs; t != NULL; t = t->next)
1702 if (strcmp (t->name, p) == 0)
1704 size_t len;
1705 char *alc;
1706 struct bfd_elf_version_expr *d;
1708 len = p - h->root.root.string;
1709 alc = bfd_malloc (len);
1710 if (alc == NULL)
1711 return FALSE;
1712 memcpy (alc, h->root.root.string, len - 1);
1713 alc[len - 1] = '\0';
1714 if (alc[len - 2] == ELF_VER_CHR)
1715 alc[len - 2] = '\0';
1717 h->verinfo.vertree = t;
1718 t->used = TRUE;
1719 d = NULL;
1721 if (t->globals.list != NULL)
1722 d = (*t->match) (&t->globals, NULL, alc);
1724 /* See if there is anything to force this symbol to
1725 local scope. */
1726 if (d == NULL && t->locals.list != NULL)
1728 d = (*t->match) (&t->locals, NULL, alc);
1729 if (d != NULL
1730 && h->dynindx != -1
1731 && info->shared
1732 && ! info->export_dynamic)
1733 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1736 free (alc);
1737 break;
1741 /* If we are building an application, we need to create a
1742 version node for this version. */
1743 if (t == NULL && info->executable)
1745 struct bfd_elf_version_tree **pp;
1746 int version_index;
1748 /* If we aren't going to export this symbol, we don't need
1749 to worry about it. */
1750 if (h->dynindx == -1)
1751 return TRUE;
1753 amt = sizeof *t;
1754 t = bfd_zalloc (sinfo->output_bfd, amt);
1755 if (t == NULL)
1757 sinfo->failed = TRUE;
1758 return FALSE;
1761 t->name = p;
1762 t->name_indx = (unsigned int) -1;
1763 t->used = TRUE;
1765 version_index = 1;
1766 /* Don't count anonymous version tag. */
1767 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1768 version_index = 0;
1769 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1770 ++version_index;
1771 t->vernum = version_index;
1773 *pp = t;
1775 h->verinfo.vertree = t;
1777 else if (t == NULL)
1779 /* We could not find the version for a symbol when
1780 generating a shared archive. Return an error. */
1781 (*_bfd_error_handler)
1782 (_("%B: undefined versioned symbol name %s"),
1783 sinfo->output_bfd, h->root.root.string);
1784 bfd_set_error (bfd_error_bad_value);
1785 sinfo->failed = TRUE;
1786 return FALSE;
1789 if (hidden)
1790 h->hidden = 1;
1793 /* If we don't have a version for this symbol, see if we can find
1794 something. */
1795 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1797 struct bfd_elf_version_tree *t;
1798 struct bfd_elf_version_tree *local_ver;
1799 struct bfd_elf_version_expr *d;
1801 /* See if can find what version this symbol is in. If the
1802 symbol is supposed to be local, then don't actually register
1803 it. */
1804 local_ver = NULL;
1805 for (t = sinfo->verdefs; t != NULL; t = t->next)
1807 if (t->globals.list != NULL)
1809 bfd_boolean matched;
1811 matched = FALSE;
1812 d = NULL;
1813 while ((d = (*t->match) (&t->globals, d,
1814 h->root.root.string)) != NULL)
1815 if (d->symver)
1816 matched = TRUE;
1817 else
1819 /* There is a version without definition. Make
1820 the symbol the default definition for this
1821 version. */
1822 h->verinfo.vertree = t;
1823 local_ver = NULL;
1824 d->script = 1;
1825 break;
1827 if (d != NULL)
1828 break;
1829 else if (matched)
1830 /* There is no undefined version for this symbol. Hide the
1831 default one. */
1832 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1835 if (t->locals.list != NULL)
1837 d = NULL;
1838 while ((d = (*t->match) (&t->locals, d,
1839 h->root.root.string)) != NULL)
1841 local_ver = t;
1842 /* If the match is "*", keep looking for a more
1843 explicit, perhaps even global, match.
1844 XXX: Shouldn't this be !d->wildcard instead? */
1845 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1846 break;
1849 if (d != NULL)
1850 break;
1854 if (local_ver != NULL)
1856 h->verinfo.vertree = local_ver;
1857 if (h->dynindx != -1
1858 && info->shared
1859 && ! info->export_dynamic)
1861 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1866 return TRUE;
1869 /* Read and swap the relocs from the section indicated by SHDR. This
1870 may be either a REL or a RELA section. The relocations are
1871 translated into RELA relocations and stored in INTERNAL_RELOCS,
1872 which should have already been allocated to contain enough space.
1873 The EXTERNAL_RELOCS are a buffer where the external form of the
1874 relocations should be stored.
1876 Returns FALSE if something goes wrong. */
1878 static bfd_boolean
1879 elf_link_read_relocs_from_section (bfd *abfd,
1880 asection *sec,
1881 Elf_Internal_Shdr *shdr,
1882 void *external_relocs,
1883 Elf_Internal_Rela *internal_relocs)
1885 const struct elf_backend_data *bed;
1886 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1887 const bfd_byte *erela;
1888 const bfd_byte *erelaend;
1889 Elf_Internal_Rela *irela;
1890 Elf_Internal_Shdr *symtab_hdr;
1891 size_t nsyms;
1893 /* Position ourselves at the start of the section. */
1894 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1895 return FALSE;
1897 /* Read the relocations. */
1898 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1899 return FALSE;
1901 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1902 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1904 bed = get_elf_backend_data (abfd);
1906 /* Convert the external relocations to the internal format. */
1907 if (shdr->sh_entsize == bed->s->sizeof_rel)
1908 swap_in = bed->s->swap_reloc_in;
1909 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1910 swap_in = bed->s->swap_reloca_in;
1911 else
1913 bfd_set_error (bfd_error_wrong_format);
1914 return FALSE;
1917 erela = external_relocs;
1918 erelaend = erela + shdr->sh_size;
1919 irela = internal_relocs;
1920 while (erela < erelaend)
1922 bfd_vma r_symndx;
1924 (*swap_in) (abfd, erela, irela);
1925 r_symndx = ELF32_R_SYM (irela->r_info);
1926 if (bed->s->arch_size == 64)
1927 r_symndx >>= 24;
1928 if ((size_t) r_symndx >= nsyms)
1930 (*_bfd_error_handler)
1931 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
1932 " for offset 0x%lx in section `%A'"),
1933 abfd, sec,
1934 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
1935 bfd_set_error (bfd_error_bad_value);
1936 return FALSE;
1938 irela += bed->s->int_rels_per_ext_rel;
1939 erela += shdr->sh_entsize;
1942 return TRUE;
1945 /* Read and swap the relocs for a section O. They may have been
1946 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
1947 not NULL, they are used as buffers to read into. They are known to
1948 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
1949 the return value is allocated using either malloc or bfd_alloc,
1950 according to the KEEP_MEMORY argument. If O has two relocation
1951 sections (both REL and RELA relocations), then the REL_HDR
1952 relocations will appear first in INTERNAL_RELOCS, followed by the
1953 REL_HDR2 relocations. */
1955 Elf_Internal_Rela *
1956 _bfd_elf_link_read_relocs (bfd *abfd,
1957 asection *o,
1958 void *external_relocs,
1959 Elf_Internal_Rela *internal_relocs,
1960 bfd_boolean keep_memory)
1962 Elf_Internal_Shdr *rel_hdr;
1963 void *alloc1 = NULL;
1964 Elf_Internal_Rela *alloc2 = NULL;
1965 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1967 if (elf_section_data (o)->relocs != NULL)
1968 return elf_section_data (o)->relocs;
1970 if (o->reloc_count == 0)
1971 return NULL;
1973 rel_hdr = &elf_section_data (o)->rel_hdr;
1975 if (internal_relocs == NULL)
1977 bfd_size_type size;
1979 size = o->reloc_count;
1980 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
1981 if (keep_memory)
1982 internal_relocs = bfd_alloc (abfd, size);
1983 else
1984 internal_relocs = alloc2 = bfd_malloc (size);
1985 if (internal_relocs == NULL)
1986 goto error_return;
1989 if (external_relocs == NULL)
1991 bfd_size_type size = rel_hdr->sh_size;
1993 if (elf_section_data (o)->rel_hdr2)
1994 size += elf_section_data (o)->rel_hdr2->sh_size;
1995 alloc1 = bfd_malloc (size);
1996 if (alloc1 == NULL)
1997 goto error_return;
1998 external_relocs = alloc1;
2001 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2002 external_relocs,
2003 internal_relocs))
2004 goto error_return;
2005 if (elf_section_data (o)->rel_hdr2
2006 && (!elf_link_read_relocs_from_section
2007 (abfd, o,
2008 elf_section_data (o)->rel_hdr2,
2009 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2010 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2011 * bed->s->int_rels_per_ext_rel))))
2012 goto error_return;
2014 /* Cache the results for next time, if we can. */
2015 if (keep_memory)
2016 elf_section_data (o)->relocs = internal_relocs;
2018 if (alloc1 != NULL)
2019 free (alloc1);
2021 /* Don't free alloc2, since if it was allocated we are passing it
2022 back (under the name of internal_relocs). */
2024 return internal_relocs;
2026 error_return:
2027 if (alloc1 != NULL)
2028 free (alloc1);
2029 if (alloc2 != NULL)
2030 free (alloc2);
2031 return NULL;
2034 /* Compute the size of, and allocate space for, REL_HDR which is the
2035 section header for a section containing relocations for O. */
2037 bfd_boolean
2038 _bfd_elf_link_size_reloc_section (bfd *abfd,
2039 Elf_Internal_Shdr *rel_hdr,
2040 asection *o)
2042 bfd_size_type reloc_count;
2043 bfd_size_type num_rel_hashes;
2045 /* Figure out how many relocations there will be. */
2046 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2047 reloc_count = elf_section_data (o)->rel_count;
2048 else
2049 reloc_count = elf_section_data (o)->rel_count2;
2051 num_rel_hashes = o->reloc_count;
2052 if (num_rel_hashes < reloc_count)
2053 num_rel_hashes = reloc_count;
2055 /* That allows us to calculate the size of the section. */
2056 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2058 /* The contents field must last into write_object_contents, so we
2059 allocate it with bfd_alloc rather than malloc. Also since we
2060 cannot be sure that the contents will actually be filled in,
2061 we zero the allocated space. */
2062 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2063 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2064 return FALSE;
2066 /* We only allocate one set of hash entries, so we only do it the
2067 first time we are called. */
2068 if (elf_section_data (o)->rel_hashes == NULL
2069 && num_rel_hashes)
2071 struct elf_link_hash_entry **p;
2073 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2074 if (p == NULL)
2075 return FALSE;
2077 elf_section_data (o)->rel_hashes = p;
2080 return TRUE;
2083 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2084 originated from the section given by INPUT_REL_HDR) to the
2085 OUTPUT_BFD. */
2087 bfd_boolean
2088 _bfd_elf_link_output_relocs (bfd *output_bfd,
2089 asection *input_section,
2090 Elf_Internal_Shdr *input_rel_hdr,
2091 Elf_Internal_Rela *internal_relocs)
2093 Elf_Internal_Rela *irela;
2094 Elf_Internal_Rela *irelaend;
2095 bfd_byte *erel;
2096 Elf_Internal_Shdr *output_rel_hdr;
2097 asection *output_section;
2098 unsigned int *rel_countp = NULL;
2099 const struct elf_backend_data *bed;
2100 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2102 output_section = input_section->output_section;
2103 output_rel_hdr = NULL;
2105 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2106 == input_rel_hdr->sh_entsize)
2108 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2109 rel_countp = &elf_section_data (output_section)->rel_count;
2111 else if (elf_section_data (output_section)->rel_hdr2
2112 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2113 == input_rel_hdr->sh_entsize))
2115 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2116 rel_countp = &elf_section_data (output_section)->rel_count2;
2118 else
2120 (*_bfd_error_handler)
2121 (_("%B: relocation size mismatch in %B section %A"),
2122 output_bfd, input_section->owner, input_section);
2123 bfd_set_error (bfd_error_wrong_object_format);
2124 return FALSE;
2127 bed = get_elf_backend_data (output_bfd);
2128 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2129 swap_out = bed->s->swap_reloc_out;
2130 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2131 swap_out = bed->s->swap_reloca_out;
2132 else
2133 abort ();
2135 erel = output_rel_hdr->contents;
2136 erel += *rel_countp * input_rel_hdr->sh_entsize;
2137 irela = internal_relocs;
2138 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2139 * bed->s->int_rels_per_ext_rel);
2140 while (irela < irelaend)
2142 (*swap_out) (output_bfd, irela, erel);
2143 irela += bed->s->int_rels_per_ext_rel;
2144 erel += input_rel_hdr->sh_entsize;
2147 /* Bump the counter, so that we know where to add the next set of
2148 relocations. */
2149 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2151 return TRUE;
2154 /* Fix up the flags for a symbol. This handles various cases which
2155 can only be fixed after all the input files are seen. This is
2156 currently called by both adjust_dynamic_symbol and
2157 assign_sym_version, which is unnecessary but perhaps more robust in
2158 the face of future changes. */
2160 bfd_boolean
2161 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2162 struct elf_info_failed *eif)
2164 /* If this symbol was mentioned in a non-ELF file, try to set
2165 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2166 permit a non-ELF file to correctly refer to a symbol defined in
2167 an ELF dynamic object. */
2168 if (h->non_elf)
2170 while (h->root.type == bfd_link_hash_indirect)
2171 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2173 if (h->root.type != bfd_link_hash_defined
2174 && h->root.type != bfd_link_hash_defweak)
2176 h->ref_regular = 1;
2177 h->ref_regular_nonweak = 1;
2179 else
2181 if (h->root.u.def.section->owner != NULL
2182 && (bfd_get_flavour (h->root.u.def.section->owner)
2183 == bfd_target_elf_flavour))
2185 h->ref_regular = 1;
2186 h->ref_regular_nonweak = 1;
2188 else
2189 h->def_regular = 1;
2192 if (h->dynindx == -1
2193 && (h->def_dynamic
2194 || h->ref_dynamic))
2196 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2198 eif->failed = TRUE;
2199 return FALSE;
2203 else
2205 /* Unfortunately, NON_ELF is only correct if the symbol
2206 was first seen in a non-ELF file. Fortunately, if the symbol
2207 was first seen in an ELF file, we're probably OK unless the
2208 symbol was defined in a non-ELF file. Catch that case here.
2209 FIXME: We're still in trouble if the symbol was first seen in
2210 a dynamic object, and then later in a non-ELF regular object. */
2211 if ((h->root.type == bfd_link_hash_defined
2212 || h->root.type == bfd_link_hash_defweak)
2213 && !h->def_regular
2214 && (h->root.u.def.section->owner != NULL
2215 ? (bfd_get_flavour (h->root.u.def.section->owner)
2216 != bfd_target_elf_flavour)
2217 : (bfd_is_abs_section (h->root.u.def.section)
2218 && !h->def_dynamic)))
2219 h->def_regular = 1;
2222 /* If this is a final link, and the symbol was defined as a common
2223 symbol in a regular object file, and there was no definition in
2224 any dynamic object, then the linker will have allocated space for
2225 the symbol in a common section but the DEF_REGULAR
2226 flag will not have been set. */
2227 if (h->root.type == bfd_link_hash_defined
2228 && !h->def_regular
2229 && h->ref_regular
2230 && !h->def_dynamic
2231 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2232 h->def_regular = 1;
2234 /* If -Bsymbolic was used (which means to bind references to global
2235 symbols to the definition within the shared object), and this
2236 symbol was defined in a regular object, then it actually doesn't
2237 need a PLT entry. Likewise, if the symbol has non-default
2238 visibility. If the symbol has hidden or internal visibility, we
2239 will force it local. */
2240 if (h->needs_plt
2241 && eif->info->shared
2242 && is_elf_hash_table (eif->info->hash)
2243 && (eif->info->symbolic
2244 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2245 && h->def_regular)
2247 const struct elf_backend_data *bed;
2248 bfd_boolean force_local;
2250 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2252 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2253 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2254 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2257 /* If a weak undefined symbol has non-default visibility, we also
2258 hide it from the dynamic linker. */
2259 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2260 && h->root.type == bfd_link_hash_undefweak)
2262 const struct elf_backend_data *bed;
2263 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2264 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2267 /* If this is a weak defined symbol in a dynamic object, and we know
2268 the real definition in the dynamic object, copy interesting flags
2269 over to the real definition. */
2270 if (h->u.weakdef != NULL)
2272 struct elf_link_hash_entry *weakdef;
2274 weakdef = h->u.weakdef;
2275 if (h->root.type == bfd_link_hash_indirect)
2276 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2278 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2279 || h->root.type == bfd_link_hash_defweak);
2280 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2281 || weakdef->root.type == bfd_link_hash_defweak);
2282 BFD_ASSERT (weakdef->def_dynamic);
2284 /* If the real definition is defined by a regular object file,
2285 don't do anything special. See the longer description in
2286 _bfd_elf_adjust_dynamic_symbol, below. */
2287 if (weakdef->def_regular)
2288 h->u.weakdef = NULL;
2289 else
2291 const struct elf_backend_data *bed;
2293 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2294 (*bed->elf_backend_copy_indirect_symbol) (bed, weakdef, h);
2298 return TRUE;
2301 /* Make the backend pick a good value for a dynamic symbol. This is
2302 called via elf_link_hash_traverse, and also calls itself
2303 recursively. */
2305 bfd_boolean
2306 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2308 struct elf_info_failed *eif = data;
2309 bfd *dynobj;
2310 const struct elf_backend_data *bed;
2312 if (! is_elf_hash_table (eif->info->hash))
2313 return FALSE;
2315 if (h->root.type == bfd_link_hash_warning)
2317 h->plt = elf_hash_table (eif->info)->init_offset;
2318 h->got = elf_hash_table (eif->info)->init_offset;
2320 /* When warning symbols are created, they **replace** the "real"
2321 entry in the hash table, thus we never get to see the real
2322 symbol in a hash traversal. So look at it now. */
2323 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2326 /* Ignore indirect symbols. These are added by the versioning code. */
2327 if (h->root.type == bfd_link_hash_indirect)
2328 return TRUE;
2330 /* Fix the symbol flags. */
2331 if (! _bfd_elf_fix_symbol_flags (h, eif))
2332 return FALSE;
2334 /* If this symbol does not require a PLT entry, and it is not
2335 defined by a dynamic object, or is not referenced by a regular
2336 object, ignore it. We do have to handle a weak defined symbol,
2337 even if no regular object refers to it, if we decided to add it
2338 to the dynamic symbol table. FIXME: Do we normally need to worry
2339 about symbols which are defined by one dynamic object and
2340 referenced by another one? */
2341 if (!h->needs_plt
2342 && (h->def_regular
2343 || !h->def_dynamic
2344 || (!h->ref_regular
2345 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2347 h->plt = elf_hash_table (eif->info)->init_offset;
2348 return TRUE;
2351 /* If we've already adjusted this symbol, don't do it again. This
2352 can happen via a recursive call. */
2353 if (h->dynamic_adjusted)
2354 return TRUE;
2356 /* Don't look at this symbol again. Note that we must set this
2357 after checking the above conditions, because we may look at a
2358 symbol once, decide not to do anything, and then get called
2359 recursively later after REF_REGULAR is set below. */
2360 h->dynamic_adjusted = 1;
2362 /* If this is a weak definition, and we know a real definition, and
2363 the real symbol is not itself defined by a regular object file,
2364 then get a good value for the real definition. We handle the
2365 real symbol first, for the convenience of the backend routine.
2367 Note that there is a confusing case here. If the real definition
2368 is defined by a regular object file, we don't get the real symbol
2369 from the dynamic object, but we do get the weak symbol. If the
2370 processor backend uses a COPY reloc, then if some routine in the
2371 dynamic object changes the real symbol, we will not see that
2372 change in the corresponding weak symbol. This is the way other
2373 ELF linkers work as well, and seems to be a result of the shared
2374 library model.
2376 I will clarify this issue. Most SVR4 shared libraries define the
2377 variable _timezone and define timezone as a weak synonym. The
2378 tzset call changes _timezone. If you write
2379 extern int timezone;
2380 int _timezone = 5;
2381 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2382 you might expect that, since timezone is a synonym for _timezone,
2383 the same number will print both times. However, if the processor
2384 backend uses a COPY reloc, then actually timezone will be copied
2385 into your process image, and, since you define _timezone
2386 yourself, _timezone will not. Thus timezone and _timezone will
2387 wind up at different memory locations. The tzset call will set
2388 _timezone, leaving timezone unchanged. */
2390 if (h->u.weakdef != NULL)
2392 /* If we get to this point, we know there is an implicit
2393 reference by a regular object file via the weak symbol H.
2394 FIXME: Is this really true? What if the traversal finds
2395 H->U.WEAKDEF before it finds H? */
2396 h->u.weakdef->ref_regular = 1;
2398 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2399 return FALSE;
2402 /* If a symbol has no type and no size and does not require a PLT
2403 entry, then we are probably about to do the wrong thing here: we
2404 are probably going to create a COPY reloc for an empty object.
2405 This case can arise when a shared object is built with assembly
2406 code, and the assembly code fails to set the symbol type. */
2407 if (h->size == 0
2408 && h->type == STT_NOTYPE
2409 && !h->needs_plt)
2410 (*_bfd_error_handler)
2411 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2412 h->root.root.string);
2414 dynobj = elf_hash_table (eif->info)->dynobj;
2415 bed = get_elf_backend_data (dynobj);
2416 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2418 eif->failed = TRUE;
2419 return FALSE;
2422 return TRUE;
2425 /* Adjust all external symbols pointing into SEC_MERGE sections
2426 to reflect the object merging within the sections. */
2428 bfd_boolean
2429 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2431 asection *sec;
2433 if (h->root.type == bfd_link_hash_warning)
2434 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2436 if ((h->root.type == bfd_link_hash_defined
2437 || h->root.type == bfd_link_hash_defweak)
2438 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2439 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2441 bfd *output_bfd = data;
2443 h->root.u.def.value =
2444 _bfd_merged_section_offset (output_bfd,
2445 &h->root.u.def.section,
2446 elf_section_data (sec)->sec_info,
2447 h->root.u.def.value);
2450 return TRUE;
2453 /* Returns false if the symbol referred to by H should be considered
2454 to resolve local to the current module, and true if it should be
2455 considered to bind dynamically. */
2457 bfd_boolean
2458 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2459 struct bfd_link_info *info,
2460 bfd_boolean ignore_protected)
2462 bfd_boolean binding_stays_local_p;
2464 if (h == NULL)
2465 return FALSE;
2467 while (h->root.type == bfd_link_hash_indirect
2468 || h->root.type == bfd_link_hash_warning)
2469 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2471 /* If it was forced local, then clearly it's not dynamic. */
2472 if (h->dynindx == -1)
2473 return FALSE;
2474 if (h->forced_local)
2475 return FALSE;
2477 /* Identify the cases where name binding rules say that a
2478 visible symbol resolves locally. */
2479 binding_stays_local_p = info->executable || info->symbolic;
2481 switch (ELF_ST_VISIBILITY (h->other))
2483 case STV_INTERNAL:
2484 case STV_HIDDEN:
2485 return FALSE;
2487 case STV_PROTECTED:
2488 /* Proper resolution for function pointer equality may require
2489 that these symbols perhaps be resolved dynamically, even though
2490 we should be resolving them to the current module. */
2491 if (!ignore_protected || h->type != STT_FUNC)
2492 binding_stays_local_p = TRUE;
2493 break;
2495 default:
2496 break;
2499 /* If it isn't defined locally, then clearly it's dynamic. */
2500 if (!h->def_regular)
2501 return TRUE;
2503 /* Otherwise, the symbol is dynamic if binding rules don't tell
2504 us that it remains local. */
2505 return !binding_stays_local_p;
2508 /* Return true if the symbol referred to by H should be considered
2509 to resolve local to the current module, and false otherwise. Differs
2510 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2511 undefined symbols and weak symbols. */
2513 bfd_boolean
2514 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2515 struct bfd_link_info *info,
2516 bfd_boolean local_protected)
2518 /* If it's a local sym, of course we resolve locally. */
2519 if (h == NULL)
2520 return TRUE;
2522 /* Common symbols that become definitions don't get the DEF_REGULAR
2523 flag set, so test it first, and don't bail out. */
2524 if (ELF_COMMON_DEF_P (h))
2525 /* Do nothing. */;
2526 /* If we don't have a definition in a regular file, then we can't
2527 resolve locally. The sym is either undefined or dynamic. */
2528 else if (!h->def_regular)
2529 return FALSE;
2531 /* Forced local symbols resolve locally. */
2532 if (h->forced_local)
2533 return TRUE;
2535 /* As do non-dynamic symbols. */
2536 if (h->dynindx == -1)
2537 return TRUE;
2539 /* At this point, we know the symbol is defined and dynamic. In an
2540 executable it must resolve locally, likewise when building symbolic
2541 shared libraries. */
2542 if (info->executable || info->symbolic)
2543 return TRUE;
2545 /* Now deal with defined dynamic symbols in shared libraries. Ones
2546 with default visibility might not resolve locally. */
2547 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2548 return FALSE;
2550 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2551 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2552 return TRUE;
2554 /* STV_PROTECTED non-function symbols are local. */
2555 if (h->type != STT_FUNC)
2556 return TRUE;
2558 /* Function pointer equality tests may require that STV_PROTECTED
2559 symbols be treated as dynamic symbols, even when we know that the
2560 dynamic linker will resolve them locally. */
2561 return local_protected;
2564 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2565 aligned. Returns the first TLS output section. */
2567 struct bfd_section *
2568 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2570 struct bfd_section *sec, *tls;
2571 unsigned int align = 0;
2573 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2574 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2575 break;
2576 tls = sec;
2578 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2579 if (sec->alignment_power > align)
2580 align = sec->alignment_power;
2582 elf_hash_table (info)->tls_sec = tls;
2584 /* Ensure the alignment of the first section is the largest alignment,
2585 so that the tls segment starts aligned. */
2586 if (tls != NULL)
2587 tls->alignment_power = align;
2589 return tls;
2592 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2593 static bfd_boolean
2594 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2595 Elf_Internal_Sym *sym)
2597 /* Local symbols do not count, but target specific ones might. */
2598 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2599 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2600 return FALSE;
2602 /* Function symbols do not count. */
2603 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2604 return FALSE;
2606 /* If the section is undefined, then so is the symbol. */
2607 if (sym->st_shndx == SHN_UNDEF)
2608 return FALSE;
2610 /* If the symbol is defined in the common section, then
2611 it is a common definition and so does not count. */
2612 if (sym->st_shndx == SHN_COMMON)
2613 return FALSE;
2615 /* If the symbol is in a target specific section then we
2616 must rely upon the backend to tell us what it is. */
2617 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2618 /* FIXME - this function is not coded yet:
2620 return _bfd_is_global_symbol_definition (abfd, sym);
2622 Instead for now assume that the definition is not global,
2623 Even if this is wrong, at least the linker will behave
2624 in the same way that it used to do. */
2625 return FALSE;
2627 return TRUE;
2630 /* Search the symbol table of the archive element of the archive ABFD
2631 whose archive map contains a mention of SYMDEF, and determine if
2632 the symbol is defined in this element. */
2633 static bfd_boolean
2634 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2636 Elf_Internal_Shdr * hdr;
2637 bfd_size_type symcount;
2638 bfd_size_type extsymcount;
2639 bfd_size_type extsymoff;
2640 Elf_Internal_Sym *isymbuf;
2641 Elf_Internal_Sym *isym;
2642 Elf_Internal_Sym *isymend;
2643 bfd_boolean result;
2645 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2646 if (abfd == NULL)
2647 return FALSE;
2649 if (! bfd_check_format (abfd, bfd_object))
2650 return FALSE;
2652 /* If we have already included the element containing this symbol in the
2653 link then we do not need to include it again. Just claim that any symbol
2654 it contains is not a definition, so that our caller will not decide to
2655 (re)include this element. */
2656 if (abfd->archive_pass)
2657 return FALSE;
2659 /* Select the appropriate symbol table. */
2660 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2661 hdr = &elf_tdata (abfd)->symtab_hdr;
2662 else
2663 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2665 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2667 /* The sh_info field of the symtab header tells us where the
2668 external symbols start. We don't care about the local symbols. */
2669 if (elf_bad_symtab (abfd))
2671 extsymcount = symcount;
2672 extsymoff = 0;
2674 else
2676 extsymcount = symcount - hdr->sh_info;
2677 extsymoff = hdr->sh_info;
2680 if (extsymcount == 0)
2681 return FALSE;
2683 /* Read in the symbol table. */
2684 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2685 NULL, NULL, NULL);
2686 if (isymbuf == NULL)
2687 return FALSE;
2689 /* Scan the symbol table looking for SYMDEF. */
2690 result = FALSE;
2691 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2693 const char *name;
2695 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2696 isym->st_name);
2697 if (name == NULL)
2698 break;
2700 if (strcmp (name, symdef->name) == 0)
2702 result = is_global_data_symbol_definition (abfd, isym);
2703 break;
2707 free (isymbuf);
2709 return result;
2712 /* Add an entry to the .dynamic table. */
2714 bfd_boolean
2715 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2716 bfd_vma tag,
2717 bfd_vma val)
2719 struct elf_link_hash_table *hash_table;
2720 const struct elf_backend_data *bed;
2721 asection *s;
2722 bfd_size_type newsize;
2723 bfd_byte *newcontents;
2724 Elf_Internal_Dyn dyn;
2726 hash_table = elf_hash_table (info);
2727 if (! is_elf_hash_table (hash_table))
2728 return FALSE;
2730 if (info->warn_shared_textrel && info->shared && tag == DT_TEXTREL)
2731 _bfd_error_handler
2732 (_("warning: creating a DT_TEXTREL in a shared object."));
2734 bed = get_elf_backend_data (hash_table->dynobj);
2735 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2736 BFD_ASSERT (s != NULL);
2738 newsize = s->size + bed->s->sizeof_dyn;
2739 newcontents = bfd_realloc (s->contents, newsize);
2740 if (newcontents == NULL)
2741 return FALSE;
2743 dyn.d_tag = tag;
2744 dyn.d_un.d_val = val;
2745 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2747 s->size = newsize;
2748 s->contents = newcontents;
2750 return TRUE;
2753 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2754 otherwise just check whether one already exists. Returns -1 on error,
2755 1 if a DT_NEEDED tag already exists, and 0 on success. */
2757 static int
2758 elf_add_dt_needed_tag (bfd *abfd,
2759 struct bfd_link_info *info,
2760 const char *soname,
2761 bfd_boolean do_it)
2763 struct elf_link_hash_table *hash_table;
2764 bfd_size_type oldsize;
2765 bfd_size_type strindex;
2767 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2768 return -1;
2770 hash_table = elf_hash_table (info);
2771 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2772 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2773 if (strindex == (bfd_size_type) -1)
2774 return -1;
2776 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2778 asection *sdyn;
2779 const struct elf_backend_data *bed;
2780 bfd_byte *extdyn;
2782 bed = get_elf_backend_data (hash_table->dynobj);
2783 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2784 if (sdyn != NULL)
2785 for (extdyn = sdyn->contents;
2786 extdyn < sdyn->contents + sdyn->size;
2787 extdyn += bed->s->sizeof_dyn)
2789 Elf_Internal_Dyn dyn;
2791 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2792 if (dyn.d_tag == DT_NEEDED
2793 && dyn.d_un.d_val == strindex)
2795 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2796 return 1;
2801 if (do_it)
2803 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2804 return -1;
2806 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2807 return -1;
2809 else
2810 /* We were just checking for existence of the tag. */
2811 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2813 return 0;
2816 /* Called via elf_link_hash_traverse, elf_smash_syms sets all symbols
2817 belonging to NOT_NEEDED to bfd_link_hash_new. We know there are no
2818 references from regular objects to these symbols.
2820 ??? Should we do something about references from other dynamic
2821 obects? If not, we potentially lose some warnings about undefined
2822 symbols. But how can we recover the initial undefined / undefweak
2823 state? */
2825 struct elf_smash_syms_data
2827 bfd *not_needed;
2828 struct elf_link_hash_table *htab;
2829 bfd_boolean twiddled;
2832 static bfd_boolean
2833 elf_smash_syms (struct elf_link_hash_entry *h, void *data)
2835 struct elf_smash_syms_data *inf = (struct elf_smash_syms_data *) data;
2836 struct bfd_link_hash_entry *bh;
2838 switch (h->root.type)
2840 default:
2841 case bfd_link_hash_new:
2842 return TRUE;
2844 case bfd_link_hash_undefined:
2845 if (h->root.u.undef.abfd != inf->not_needed)
2846 return TRUE;
2847 if (h->root.u.undef.weak != NULL
2848 && h->root.u.undef.weak != inf->not_needed)
2850 /* Symbol was undefweak in u.undef.weak bfd, and has become
2851 undefined in as-needed lib. Restore weak. */
2852 h->root.type = bfd_link_hash_undefweak;
2853 h->root.u.undef.abfd = h->root.u.undef.weak;
2854 if (h->root.u.undef.next != NULL
2855 || inf->htab->root.undefs_tail == &h->root)
2856 inf->twiddled = TRUE;
2857 return TRUE;
2859 break;
2861 case bfd_link_hash_undefweak:
2862 if (h->root.u.undef.abfd != inf->not_needed)
2863 return TRUE;
2864 break;
2866 case bfd_link_hash_defined:
2867 case bfd_link_hash_defweak:
2868 if (h->root.u.def.section->owner != inf->not_needed)
2869 return TRUE;
2870 break;
2872 case bfd_link_hash_common:
2873 if (h->root.u.c.p->section->owner != inf->not_needed)
2874 return TRUE;
2875 break;
2877 case bfd_link_hash_warning:
2878 case bfd_link_hash_indirect:
2879 elf_smash_syms ((struct elf_link_hash_entry *) h->root.u.i.link, data);
2880 if (h->root.u.i.link->type != bfd_link_hash_new)
2881 return TRUE;
2882 if (h->root.u.i.link->u.undef.abfd != inf->not_needed)
2883 return TRUE;
2884 break;
2887 /* There is no way we can undo symbol table state from defined or
2888 defweak back to undefined. */
2889 if (h->ref_regular)
2890 abort ();
2892 /* Set sym back to newly created state, but keep undefs list pointer. */
2893 bh = h->root.u.undef.next;
2894 if (bh != NULL || inf->htab->root.undefs_tail == &h->root)
2895 inf->twiddled = TRUE;
2896 (*inf->htab->root.table.newfunc) (&h->root.root,
2897 &inf->htab->root.table,
2898 h->root.root.string);
2899 h->root.u.undef.next = bh;
2900 h->root.u.undef.abfd = inf->not_needed;
2901 h->non_elf = 0;
2902 return TRUE;
2905 /* Sort symbol by value and section. */
2906 static int
2907 elf_sort_symbol (const void *arg1, const void *arg2)
2909 const struct elf_link_hash_entry *h1;
2910 const struct elf_link_hash_entry *h2;
2911 bfd_signed_vma vdiff;
2913 h1 = *(const struct elf_link_hash_entry **) arg1;
2914 h2 = *(const struct elf_link_hash_entry **) arg2;
2915 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2916 if (vdiff != 0)
2917 return vdiff > 0 ? 1 : -1;
2918 else
2920 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2921 if (sdiff != 0)
2922 return sdiff > 0 ? 1 : -1;
2924 return 0;
2927 /* This function is used to adjust offsets into .dynstr for
2928 dynamic symbols. This is called via elf_link_hash_traverse. */
2930 static bfd_boolean
2931 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
2933 struct elf_strtab_hash *dynstr = data;
2935 if (h->root.type == bfd_link_hash_warning)
2936 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2938 if (h->dynindx != -1)
2939 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
2940 return TRUE;
2943 /* Assign string offsets in .dynstr, update all structures referencing
2944 them. */
2946 static bfd_boolean
2947 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
2949 struct elf_link_hash_table *hash_table = elf_hash_table (info);
2950 struct elf_link_local_dynamic_entry *entry;
2951 struct elf_strtab_hash *dynstr = hash_table->dynstr;
2952 bfd *dynobj = hash_table->dynobj;
2953 asection *sdyn;
2954 bfd_size_type size;
2955 const struct elf_backend_data *bed;
2956 bfd_byte *extdyn;
2958 _bfd_elf_strtab_finalize (dynstr);
2959 size = _bfd_elf_strtab_size (dynstr);
2961 bed = get_elf_backend_data (dynobj);
2962 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2963 BFD_ASSERT (sdyn != NULL);
2965 /* Update all .dynamic entries referencing .dynstr strings. */
2966 for (extdyn = sdyn->contents;
2967 extdyn < sdyn->contents + sdyn->size;
2968 extdyn += bed->s->sizeof_dyn)
2970 Elf_Internal_Dyn dyn;
2972 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
2973 switch (dyn.d_tag)
2975 case DT_STRSZ:
2976 dyn.d_un.d_val = size;
2977 break;
2978 case DT_NEEDED:
2979 case DT_SONAME:
2980 case DT_RPATH:
2981 case DT_RUNPATH:
2982 case DT_FILTER:
2983 case DT_AUXILIARY:
2984 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
2985 break;
2986 default:
2987 continue;
2989 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
2992 /* Now update local dynamic symbols. */
2993 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
2994 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
2995 entry->isym.st_name);
2997 /* And the rest of dynamic symbols. */
2998 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3000 /* Adjust version definitions. */
3001 if (elf_tdata (output_bfd)->cverdefs)
3003 asection *s;
3004 bfd_byte *p;
3005 bfd_size_type i;
3006 Elf_Internal_Verdef def;
3007 Elf_Internal_Verdaux defaux;
3009 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3010 p = s->contents;
3013 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3014 &def);
3015 p += sizeof (Elf_External_Verdef);
3016 if (def.vd_aux != sizeof (Elf_External_Verdef))
3017 continue;
3018 for (i = 0; i < def.vd_cnt; ++i)
3020 _bfd_elf_swap_verdaux_in (output_bfd,
3021 (Elf_External_Verdaux *) p, &defaux);
3022 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3023 defaux.vda_name);
3024 _bfd_elf_swap_verdaux_out (output_bfd,
3025 &defaux, (Elf_External_Verdaux *) p);
3026 p += sizeof (Elf_External_Verdaux);
3029 while (def.vd_next);
3032 /* Adjust version references. */
3033 if (elf_tdata (output_bfd)->verref)
3035 asection *s;
3036 bfd_byte *p;
3037 bfd_size_type i;
3038 Elf_Internal_Verneed need;
3039 Elf_Internal_Vernaux needaux;
3041 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3042 p = s->contents;
3045 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3046 &need);
3047 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3048 _bfd_elf_swap_verneed_out (output_bfd, &need,
3049 (Elf_External_Verneed *) p);
3050 p += sizeof (Elf_External_Verneed);
3051 for (i = 0; i < need.vn_cnt; ++i)
3053 _bfd_elf_swap_vernaux_in (output_bfd,
3054 (Elf_External_Vernaux *) p, &needaux);
3055 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3056 needaux.vna_name);
3057 _bfd_elf_swap_vernaux_out (output_bfd,
3058 &needaux,
3059 (Elf_External_Vernaux *) p);
3060 p += sizeof (Elf_External_Vernaux);
3063 while (need.vn_next);
3066 return TRUE;
3069 /* Add symbols from an ELF object file to the linker hash table. */
3071 static bfd_boolean
3072 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3074 bfd_boolean (*add_symbol_hook)
3075 (bfd *, struct bfd_link_info *, Elf_Internal_Sym *,
3076 const char **, flagword *, asection **, bfd_vma *);
3077 bfd_boolean (*check_relocs)
3078 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
3079 bfd_boolean (*check_directives)
3080 (bfd *, struct bfd_link_info *);
3081 bfd_boolean collect;
3082 Elf_Internal_Shdr *hdr;
3083 bfd_size_type symcount;
3084 bfd_size_type extsymcount;
3085 bfd_size_type extsymoff;
3086 struct elf_link_hash_entry **sym_hash;
3087 bfd_boolean dynamic;
3088 Elf_External_Versym *extversym = NULL;
3089 Elf_External_Versym *ever;
3090 struct elf_link_hash_entry *weaks;
3091 struct elf_link_hash_entry **nondeflt_vers = NULL;
3092 bfd_size_type nondeflt_vers_cnt = 0;
3093 Elf_Internal_Sym *isymbuf = NULL;
3094 Elf_Internal_Sym *isym;
3095 Elf_Internal_Sym *isymend;
3096 const struct elf_backend_data *bed;
3097 bfd_boolean add_needed;
3098 struct elf_link_hash_table * hash_table;
3099 bfd_size_type amt;
3101 hash_table = elf_hash_table (info);
3103 bed = get_elf_backend_data (abfd);
3104 add_symbol_hook = bed->elf_add_symbol_hook;
3105 collect = bed->collect;
3107 if ((abfd->flags & DYNAMIC) == 0)
3108 dynamic = FALSE;
3109 else
3111 dynamic = TRUE;
3113 /* You can't use -r against a dynamic object. Also, there's no
3114 hope of using a dynamic object which does not exactly match
3115 the format of the output file. */
3116 if (info->relocatable
3117 || !is_elf_hash_table (hash_table)
3118 || hash_table->root.creator != abfd->xvec)
3120 if (info->relocatable)
3121 bfd_set_error (bfd_error_invalid_operation);
3122 else
3123 bfd_set_error (bfd_error_wrong_format);
3124 goto error_return;
3128 /* As a GNU extension, any input sections which are named
3129 .gnu.warning.SYMBOL are treated as warning symbols for the given
3130 symbol. This differs from .gnu.warning sections, which generate
3131 warnings when they are included in an output file. */
3132 if (info->executable)
3134 asection *s;
3136 for (s = abfd->sections; s != NULL; s = s->next)
3138 const char *name;
3140 name = bfd_get_section_name (abfd, s);
3141 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
3143 char *msg;
3144 bfd_size_type sz;
3146 name += sizeof ".gnu.warning." - 1;
3148 /* If this is a shared object, then look up the symbol
3149 in the hash table. If it is there, and it is already
3150 been defined, then we will not be using the entry
3151 from this shared object, so we don't need to warn.
3152 FIXME: If we see the definition in a regular object
3153 later on, we will warn, but we shouldn't. The only
3154 fix is to keep track of what warnings we are supposed
3155 to emit, and then handle them all at the end of the
3156 link. */
3157 if (dynamic)
3159 struct elf_link_hash_entry *h;
3161 h = elf_link_hash_lookup (hash_table, name,
3162 FALSE, FALSE, TRUE);
3164 /* FIXME: What about bfd_link_hash_common? */
3165 if (h != NULL
3166 && (h->root.type == bfd_link_hash_defined
3167 || h->root.type == bfd_link_hash_defweak))
3169 /* We don't want to issue this warning. Clobber
3170 the section size so that the warning does not
3171 get copied into the output file. */
3172 s->size = 0;
3173 continue;
3177 sz = s->size;
3178 msg = bfd_alloc (abfd, sz + 1);
3179 if (msg == NULL)
3180 goto error_return;
3182 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3183 goto error_return;
3185 msg[sz] = '\0';
3187 if (! (_bfd_generic_link_add_one_symbol
3188 (info, abfd, name, BSF_WARNING, s, 0, msg,
3189 FALSE, collect, NULL)))
3190 goto error_return;
3192 if (! info->relocatable)
3194 /* Clobber the section size so that the warning does
3195 not get copied into the output file. */
3196 s->size = 0;
3202 add_needed = TRUE;
3203 if (! dynamic)
3205 /* If we are creating a shared library, create all the dynamic
3206 sections immediately. We need to attach them to something,
3207 so we attach them to this BFD, provided it is the right
3208 format. FIXME: If there are no input BFD's of the same
3209 format as the output, we can't make a shared library. */
3210 if (info->shared
3211 && is_elf_hash_table (hash_table)
3212 && hash_table->root.creator == abfd->xvec
3213 && ! hash_table->dynamic_sections_created)
3215 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3216 goto error_return;
3219 else if (!is_elf_hash_table (hash_table))
3220 goto error_return;
3221 else
3223 asection *s;
3224 const char *soname = NULL;
3225 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3226 int ret;
3228 /* ld --just-symbols and dynamic objects don't mix very well.
3229 Test for --just-symbols by looking at info set up by
3230 _bfd_elf_link_just_syms. */
3231 if ((s = abfd->sections) != NULL
3232 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3233 goto error_return;
3235 /* If this dynamic lib was specified on the command line with
3236 --as-needed in effect, then we don't want to add a DT_NEEDED
3237 tag unless the lib is actually used. Similary for libs brought
3238 in by another lib's DT_NEEDED. When --no-add-needed is used
3239 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3240 any dynamic library in DT_NEEDED tags in the dynamic lib at
3241 all. */
3242 add_needed = (elf_dyn_lib_class (abfd)
3243 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3244 | DYN_NO_NEEDED)) == 0;
3246 s = bfd_get_section_by_name (abfd, ".dynamic");
3247 if (s != NULL)
3249 bfd_byte *dynbuf;
3250 bfd_byte *extdyn;
3251 int elfsec;
3252 unsigned long shlink;
3254 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3255 goto error_free_dyn;
3257 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3258 if (elfsec == -1)
3259 goto error_free_dyn;
3260 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3262 for (extdyn = dynbuf;
3263 extdyn < dynbuf + s->size;
3264 extdyn += bed->s->sizeof_dyn)
3266 Elf_Internal_Dyn dyn;
3268 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3269 if (dyn.d_tag == DT_SONAME)
3271 unsigned int tagv = dyn.d_un.d_val;
3272 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3273 if (soname == NULL)
3274 goto error_free_dyn;
3276 if (dyn.d_tag == DT_NEEDED)
3278 struct bfd_link_needed_list *n, **pn;
3279 char *fnm, *anm;
3280 unsigned int tagv = dyn.d_un.d_val;
3282 amt = sizeof (struct bfd_link_needed_list);
3283 n = bfd_alloc (abfd, amt);
3284 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3285 if (n == NULL || fnm == NULL)
3286 goto error_free_dyn;
3287 amt = strlen (fnm) + 1;
3288 anm = bfd_alloc (abfd, amt);
3289 if (anm == NULL)
3290 goto error_free_dyn;
3291 memcpy (anm, fnm, amt);
3292 n->name = anm;
3293 n->by = abfd;
3294 n->next = NULL;
3295 for (pn = & hash_table->needed;
3296 *pn != NULL;
3297 pn = &(*pn)->next)
3299 *pn = n;
3301 if (dyn.d_tag == DT_RUNPATH)
3303 struct bfd_link_needed_list *n, **pn;
3304 char *fnm, *anm;
3305 unsigned int tagv = dyn.d_un.d_val;
3307 amt = sizeof (struct bfd_link_needed_list);
3308 n = bfd_alloc (abfd, amt);
3309 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3310 if (n == NULL || fnm == NULL)
3311 goto error_free_dyn;
3312 amt = strlen (fnm) + 1;
3313 anm = bfd_alloc (abfd, amt);
3314 if (anm == NULL)
3315 goto error_free_dyn;
3316 memcpy (anm, fnm, amt);
3317 n->name = anm;
3318 n->by = abfd;
3319 n->next = NULL;
3320 for (pn = & runpath;
3321 *pn != NULL;
3322 pn = &(*pn)->next)
3324 *pn = n;
3326 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3327 if (!runpath && dyn.d_tag == DT_RPATH)
3329 struct bfd_link_needed_list *n, **pn;
3330 char *fnm, *anm;
3331 unsigned int tagv = dyn.d_un.d_val;
3333 amt = sizeof (struct bfd_link_needed_list);
3334 n = bfd_alloc (abfd, amt);
3335 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3336 if (n == NULL || fnm == NULL)
3337 goto error_free_dyn;
3338 amt = strlen (fnm) + 1;
3339 anm = bfd_alloc (abfd, amt);
3340 if (anm == NULL)
3342 error_free_dyn:
3343 free (dynbuf);
3344 goto error_return;
3346 memcpy (anm, fnm, amt);
3347 n->name = anm;
3348 n->by = abfd;
3349 n->next = NULL;
3350 for (pn = & rpath;
3351 *pn != NULL;
3352 pn = &(*pn)->next)
3354 *pn = n;
3358 free (dynbuf);
3361 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3362 frees all more recently bfd_alloc'd blocks as well. */
3363 if (runpath)
3364 rpath = runpath;
3366 if (rpath)
3368 struct bfd_link_needed_list **pn;
3369 for (pn = & hash_table->runpath;
3370 *pn != NULL;
3371 pn = &(*pn)->next)
3373 *pn = rpath;
3376 /* We do not want to include any of the sections in a dynamic
3377 object in the output file. We hack by simply clobbering the
3378 list of sections in the BFD. This could be handled more
3379 cleanly by, say, a new section flag; the existing
3380 SEC_NEVER_LOAD flag is not the one we want, because that one
3381 still implies that the section takes up space in the output
3382 file. */
3383 bfd_section_list_clear (abfd);
3385 /* Find the name to use in a DT_NEEDED entry that refers to this
3386 object. If the object has a DT_SONAME entry, we use it.
3387 Otherwise, if the generic linker stuck something in
3388 elf_dt_name, we use that. Otherwise, we just use the file
3389 name. */
3390 if (soname == NULL || *soname == '\0')
3392 soname = elf_dt_name (abfd);
3393 if (soname == NULL || *soname == '\0')
3394 soname = bfd_get_filename (abfd);
3397 /* Save the SONAME because sometimes the linker emulation code
3398 will need to know it. */
3399 elf_dt_name (abfd) = soname;
3401 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3402 if (ret < 0)
3403 goto error_return;
3405 /* If we have already included this dynamic object in the
3406 link, just ignore it. There is no reason to include a
3407 particular dynamic object more than once. */
3408 if (ret > 0)
3409 return TRUE;
3412 /* If this is a dynamic object, we always link against the .dynsym
3413 symbol table, not the .symtab symbol table. The dynamic linker
3414 will only see the .dynsym symbol table, so there is no reason to
3415 look at .symtab for a dynamic object. */
3417 if (! dynamic || elf_dynsymtab (abfd) == 0)
3418 hdr = &elf_tdata (abfd)->symtab_hdr;
3419 else
3420 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3422 symcount = hdr->sh_size / bed->s->sizeof_sym;
3424 /* The sh_info field of the symtab header tells us where the
3425 external symbols start. We don't care about the local symbols at
3426 this point. */
3427 if (elf_bad_symtab (abfd))
3429 extsymcount = symcount;
3430 extsymoff = 0;
3432 else
3434 extsymcount = symcount - hdr->sh_info;
3435 extsymoff = hdr->sh_info;
3438 sym_hash = NULL;
3439 if (extsymcount != 0)
3441 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3442 NULL, NULL, NULL);
3443 if (isymbuf == NULL)
3444 goto error_return;
3446 /* We store a pointer to the hash table entry for each external
3447 symbol. */
3448 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3449 sym_hash = bfd_alloc (abfd, amt);
3450 if (sym_hash == NULL)
3451 goto error_free_sym;
3452 elf_sym_hashes (abfd) = sym_hash;
3455 if (dynamic)
3457 /* Read in any version definitions. */
3458 if (!_bfd_elf_slurp_version_tables (abfd,
3459 info->default_imported_symver))
3460 goto error_free_sym;
3462 /* Read in the symbol versions, but don't bother to convert them
3463 to internal format. */
3464 if (elf_dynversym (abfd) != 0)
3466 Elf_Internal_Shdr *versymhdr;
3468 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3469 extversym = bfd_malloc (versymhdr->sh_size);
3470 if (extversym == NULL)
3471 goto error_free_sym;
3472 amt = versymhdr->sh_size;
3473 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3474 || bfd_bread (extversym, amt, abfd) != amt)
3475 goto error_free_vers;
3479 weaks = NULL;
3481 ever = extversym != NULL ? extversym + extsymoff : NULL;
3482 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3483 isym < isymend;
3484 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3486 int bind;
3487 bfd_vma value;
3488 asection *sec;
3489 flagword flags;
3490 const char *name;
3491 struct elf_link_hash_entry *h;
3492 bfd_boolean definition;
3493 bfd_boolean size_change_ok;
3494 bfd_boolean type_change_ok;
3495 bfd_boolean new_weakdef;
3496 bfd_boolean override;
3497 unsigned int old_alignment;
3498 bfd *old_bfd;
3500 override = FALSE;
3502 flags = BSF_NO_FLAGS;
3503 sec = NULL;
3504 value = isym->st_value;
3505 *sym_hash = NULL;
3507 bind = ELF_ST_BIND (isym->st_info);
3508 if (bind == STB_LOCAL)
3510 /* This should be impossible, since ELF requires that all
3511 global symbols follow all local symbols, and that sh_info
3512 point to the first global symbol. Unfortunately, Irix 5
3513 screws this up. */
3514 continue;
3516 else if (bind == STB_GLOBAL)
3518 if (isym->st_shndx != SHN_UNDEF
3519 && isym->st_shndx != SHN_COMMON)
3520 flags = BSF_GLOBAL;
3522 else if (bind == STB_WEAK)
3523 flags = BSF_WEAK;
3524 else
3526 /* Leave it up to the processor backend. */
3529 if (isym->st_shndx == SHN_UNDEF)
3530 sec = bfd_und_section_ptr;
3531 else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
3533 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3534 if (sec == NULL)
3535 sec = bfd_abs_section_ptr;
3536 else if (sec->kept_section)
3538 /* Symbols from discarded section are undefined. */
3539 sec = bfd_und_section_ptr;
3540 isym->st_shndx = SHN_UNDEF;
3542 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3543 value -= sec->vma;
3545 else if (isym->st_shndx == SHN_ABS)
3546 sec = bfd_abs_section_ptr;
3547 else if (isym->st_shndx == SHN_COMMON)
3549 sec = bfd_com_section_ptr;
3550 /* What ELF calls the size we call the value. What ELF
3551 calls the value we call the alignment. */
3552 value = isym->st_size;
3554 else
3556 /* Leave it up to the processor backend. */
3559 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3560 isym->st_name);
3561 if (name == NULL)
3562 goto error_free_vers;
3564 if (isym->st_shndx == SHN_COMMON
3565 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3567 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3569 if (tcomm == NULL)
3571 tcomm = bfd_make_section (abfd, ".tcommon");
3572 if (tcomm == NULL
3573 || !bfd_set_section_flags (abfd, tcomm, (SEC_ALLOC
3574 | SEC_IS_COMMON
3575 | SEC_LINKER_CREATED
3576 | SEC_THREAD_LOCAL)))
3577 goto error_free_vers;
3579 sec = tcomm;
3581 else if (add_symbol_hook)
3583 if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec,
3584 &value))
3585 goto error_free_vers;
3587 /* The hook function sets the name to NULL if this symbol
3588 should be skipped for some reason. */
3589 if (name == NULL)
3590 continue;
3593 /* Sanity check that all possibilities were handled. */
3594 if (sec == NULL)
3596 bfd_set_error (bfd_error_bad_value);
3597 goto error_free_vers;
3600 if (bfd_is_und_section (sec)
3601 || bfd_is_com_section (sec))
3602 definition = FALSE;
3603 else
3604 definition = TRUE;
3606 size_change_ok = FALSE;
3607 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
3608 old_alignment = 0;
3609 old_bfd = NULL;
3611 if (is_elf_hash_table (hash_table))
3613 Elf_Internal_Versym iver;
3614 unsigned int vernum = 0;
3615 bfd_boolean skip;
3617 if (ever == NULL)
3619 if (info->default_imported_symver)
3620 /* Use the default symbol version created earlier. */
3621 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3622 else
3623 iver.vs_vers = 0;
3625 else
3626 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3628 vernum = iver.vs_vers & VERSYM_VERSION;
3630 /* If this is a hidden symbol, or if it is not version
3631 1, we append the version name to the symbol name.
3632 However, we do not modify a non-hidden absolute
3633 symbol, because it might be the version symbol
3634 itself. FIXME: What if it isn't? */
3635 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3636 || (vernum > 1 && ! bfd_is_abs_section (sec)))
3638 const char *verstr;
3639 size_t namelen, verlen, newlen;
3640 char *newname, *p;
3642 if (isym->st_shndx != SHN_UNDEF)
3644 if (vernum > elf_tdata (abfd)->cverdefs)
3645 verstr = NULL;
3646 else if (vernum > 1)
3647 verstr =
3648 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3649 else
3650 verstr = "";
3652 if (verstr == NULL)
3654 (*_bfd_error_handler)
3655 (_("%B: %s: invalid version %u (max %d)"),
3656 abfd, name, vernum,
3657 elf_tdata (abfd)->cverdefs);
3658 bfd_set_error (bfd_error_bad_value);
3659 goto error_free_vers;
3662 else
3664 /* We cannot simply test for the number of
3665 entries in the VERNEED section since the
3666 numbers for the needed versions do not start
3667 at 0. */
3668 Elf_Internal_Verneed *t;
3670 verstr = NULL;
3671 for (t = elf_tdata (abfd)->verref;
3672 t != NULL;
3673 t = t->vn_nextref)
3675 Elf_Internal_Vernaux *a;
3677 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3679 if (a->vna_other == vernum)
3681 verstr = a->vna_nodename;
3682 break;
3685 if (a != NULL)
3686 break;
3688 if (verstr == NULL)
3690 (*_bfd_error_handler)
3691 (_("%B: %s: invalid needed version %d"),
3692 abfd, name, vernum);
3693 bfd_set_error (bfd_error_bad_value);
3694 goto error_free_vers;
3698 namelen = strlen (name);
3699 verlen = strlen (verstr);
3700 newlen = namelen + verlen + 2;
3701 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3702 && isym->st_shndx != SHN_UNDEF)
3703 ++newlen;
3705 newname = bfd_alloc (abfd, newlen);
3706 if (newname == NULL)
3707 goto error_free_vers;
3708 memcpy (newname, name, namelen);
3709 p = newname + namelen;
3710 *p++ = ELF_VER_CHR;
3711 /* If this is a defined non-hidden version symbol,
3712 we add another @ to the name. This indicates the
3713 default version of the symbol. */
3714 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3715 && isym->st_shndx != SHN_UNDEF)
3716 *p++ = ELF_VER_CHR;
3717 memcpy (p, verstr, verlen + 1);
3719 name = newname;
3722 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec, &value,
3723 sym_hash, &skip, &override,
3724 &type_change_ok, &size_change_ok))
3725 goto error_free_vers;
3727 if (skip)
3728 continue;
3730 if (override)
3731 definition = FALSE;
3733 h = *sym_hash;
3734 while (h->root.type == bfd_link_hash_indirect
3735 || h->root.type == bfd_link_hash_warning)
3736 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3738 /* Remember the old alignment if this is a common symbol, so
3739 that we don't reduce the alignment later on. We can't
3740 check later, because _bfd_generic_link_add_one_symbol
3741 will set a default for the alignment which we want to
3742 override. We also remember the old bfd where the existing
3743 definition comes from. */
3744 switch (h->root.type)
3746 default:
3747 break;
3749 case bfd_link_hash_defined:
3750 case bfd_link_hash_defweak:
3751 old_bfd = h->root.u.def.section->owner;
3752 break;
3754 case bfd_link_hash_common:
3755 old_bfd = h->root.u.c.p->section->owner;
3756 old_alignment = h->root.u.c.p->alignment_power;
3757 break;
3760 if (elf_tdata (abfd)->verdef != NULL
3761 && ! override
3762 && vernum > 1
3763 && definition)
3764 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3767 if (! (_bfd_generic_link_add_one_symbol
3768 (info, abfd, name, flags, sec, value, NULL, FALSE, collect,
3769 (struct bfd_link_hash_entry **) sym_hash)))
3770 goto error_free_vers;
3772 h = *sym_hash;
3773 while (h->root.type == bfd_link_hash_indirect
3774 || h->root.type == bfd_link_hash_warning)
3775 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3776 *sym_hash = h;
3778 new_weakdef = FALSE;
3779 if (dynamic
3780 && definition
3781 && (flags & BSF_WEAK) != 0
3782 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3783 && is_elf_hash_table (hash_table)
3784 && h->u.weakdef == NULL)
3786 /* Keep a list of all weak defined non function symbols from
3787 a dynamic object, using the weakdef field. Later in this
3788 function we will set the weakdef field to the correct
3789 value. We only put non-function symbols from dynamic
3790 objects on this list, because that happens to be the only
3791 time we need to know the normal symbol corresponding to a
3792 weak symbol, and the information is time consuming to
3793 figure out. If the weakdef field is not already NULL,
3794 then this symbol was already defined by some previous
3795 dynamic object, and we will be using that previous
3796 definition anyhow. */
3798 h->u.weakdef = weaks;
3799 weaks = h;
3800 new_weakdef = TRUE;
3803 /* Set the alignment of a common symbol. */
3804 if (isym->st_shndx == SHN_COMMON
3805 && h->root.type == bfd_link_hash_common)
3807 unsigned int align;
3809 align = bfd_log2 (isym->st_value);
3810 if (align > old_alignment
3811 /* Permit an alignment power of zero if an alignment of one
3812 is specified and no other alignments have been specified. */
3813 || (isym->st_value == 1 && old_alignment == 0))
3814 h->root.u.c.p->alignment_power = align;
3815 else
3816 h->root.u.c.p->alignment_power = old_alignment;
3819 if (is_elf_hash_table (hash_table))
3821 bfd_boolean dynsym;
3823 /* Check the alignment when a common symbol is involved. This
3824 can change when a common symbol is overridden by a normal
3825 definition or a common symbol is ignored due to the old
3826 normal definition. We need to make sure the maximum
3827 alignment is maintained. */
3828 if ((old_alignment || isym->st_shndx == SHN_COMMON)
3829 && h->root.type != bfd_link_hash_common)
3831 unsigned int common_align;
3832 unsigned int normal_align;
3833 unsigned int symbol_align;
3834 bfd *normal_bfd;
3835 bfd *common_bfd;
3837 symbol_align = ffs (h->root.u.def.value) - 1;
3838 if (h->root.u.def.section->owner != NULL
3839 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3841 normal_align = h->root.u.def.section->alignment_power;
3842 if (normal_align > symbol_align)
3843 normal_align = symbol_align;
3845 else
3846 normal_align = symbol_align;
3848 if (old_alignment)
3850 common_align = old_alignment;
3851 common_bfd = old_bfd;
3852 normal_bfd = abfd;
3854 else
3856 common_align = bfd_log2 (isym->st_value);
3857 common_bfd = abfd;
3858 normal_bfd = old_bfd;
3861 if (normal_align < common_align)
3862 (*_bfd_error_handler)
3863 (_("Warning: alignment %u of symbol `%s' in %B"
3864 " is smaller than %u in %B"),
3865 normal_bfd, common_bfd,
3866 1 << normal_align, name, 1 << common_align);
3869 /* Remember the symbol size and type. */
3870 if (isym->st_size != 0
3871 && (definition || h->size == 0))
3873 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3874 (*_bfd_error_handler)
3875 (_("Warning: size of symbol `%s' changed"
3876 " from %lu in %B to %lu in %B"),
3877 old_bfd, abfd,
3878 name, (unsigned long) h->size,
3879 (unsigned long) isym->st_size);
3881 h->size = isym->st_size;
3884 /* If this is a common symbol, then we always want H->SIZE
3885 to be the size of the common symbol. The code just above
3886 won't fix the size if a common symbol becomes larger. We
3887 don't warn about a size change here, because that is
3888 covered by --warn-common. */
3889 if (h->root.type == bfd_link_hash_common)
3890 h->size = h->root.u.c.size;
3892 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3893 && (definition || h->type == STT_NOTYPE))
3895 if (h->type != STT_NOTYPE
3896 && h->type != ELF_ST_TYPE (isym->st_info)
3897 && ! type_change_ok)
3898 (*_bfd_error_handler)
3899 (_("Warning: type of symbol `%s' changed"
3900 " from %d to %d in %B"),
3901 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
3903 h->type = ELF_ST_TYPE (isym->st_info);
3906 /* If st_other has a processor-specific meaning, specific
3907 code might be needed here. We never merge the visibility
3908 attribute with the one from a dynamic object. */
3909 if (bed->elf_backend_merge_symbol_attribute)
3910 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3911 dynamic);
3913 /* If this symbol has default visibility and the user has requested
3914 we not re-export it, then mark it as hidden. */
3915 if (definition && !dynamic
3916 && (abfd->no_export
3917 || (abfd->my_archive && abfd->my_archive->no_export))
3918 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
3919 isym->st_other = STV_HIDDEN | (isym->st_other & ~ ELF_ST_VISIBILITY (-1));
3921 if (isym->st_other != 0 && !dynamic)
3923 unsigned char hvis, symvis, other, nvis;
3925 /* Take the balance of OTHER from the definition. */
3926 other = (definition ? isym->st_other : h->other);
3927 other &= ~ ELF_ST_VISIBILITY (-1);
3929 /* Combine visibilities, using the most constraining one. */
3930 hvis = ELF_ST_VISIBILITY (h->other);
3931 symvis = ELF_ST_VISIBILITY (isym->st_other);
3932 if (! hvis)
3933 nvis = symvis;
3934 else if (! symvis)
3935 nvis = hvis;
3936 else
3937 nvis = hvis < symvis ? hvis : symvis;
3939 h->other = other | nvis;
3942 /* Set a flag in the hash table entry indicating the type of
3943 reference or definition we just found. Keep a count of
3944 the number of dynamic symbols we find. A dynamic symbol
3945 is one which is referenced or defined by both a regular
3946 object and a shared object. */
3947 dynsym = FALSE;
3948 if (! dynamic)
3950 if (! definition)
3952 h->ref_regular = 1;
3953 if (bind != STB_WEAK)
3954 h->ref_regular_nonweak = 1;
3956 else
3957 h->def_regular = 1;
3958 if (! info->executable
3959 || h->def_dynamic
3960 || h->ref_dynamic)
3961 dynsym = TRUE;
3963 else
3965 if (! definition)
3966 h->ref_dynamic = 1;
3967 else
3968 h->def_dynamic = 1;
3969 if (h->def_regular
3970 || h->ref_regular
3971 || (h->u.weakdef != NULL
3972 && ! new_weakdef
3973 && h->u.weakdef->dynindx != -1))
3974 dynsym = TRUE;
3977 /* Check to see if we need to add an indirect symbol for
3978 the default name. */
3979 if (definition || h->root.type == bfd_link_hash_common)
3980 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
3981 &sec, &value, &dynsym,
3982 override))
3983 goto error_free_vers;
3985 if (definition && !dynamic)
3987 char *p = strchr (name, ELF_VER_CHR);
3988 if (p != NULL && p[1] != ELF_VER_CHR)
3990 /* Queue non-default versions so that .symver x, x@FOO
3991 aliases can be checked. */
3992 if (! nondeflt_vers)
3994 amt = (isymend - isym + 1)
3995 * sizeof (struct elf_link_hash_entry *);
3996 nondeflt_vers = bfd_malloc (amt);
3998 nondeflt_vers [nondeflt_vers_cnt++] = h;
4002 if (dynsym && h->dynindx == -1)
4004 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4005 goto error_free_vers;
4006 if (h->u.weakdef != NULL
4007 && ! new_weakdef
4008 && h->u.weakdef->dynindx == -1)
4010 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4011 goto error_free_vers;
4014 else if (dynsym && h->dynindx != -1)
4015 /* If the symbol already has a dynamic index, but
4016 visibility says it should not be visible, turn it into
4017 a local symbol. */
4018 switch (ELF_ST_VISIBILITY (h->other))
4020 case STV_INTERNAL:
4021 case STV_HIDDEN:
4022 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4023 dynsym = FALSE;
4024 break;
4027 if (!add_needed
4028 && definition
4029 && dynsym
4030 && h->ref_regular)
4032 int ret;
4033 const char *soname = elf_dt_name (abfd);
4035 /* A symbol from a library loaded via DT_NEEDED of some
4036 other library is referenced by a regular object.
4037 Add a DT_NEEDED entry for it. Issue an error if
4038 --no-add-needed is used. */
4039 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4041 (*_bfd_error_handler)
4042 (_("%s: invalid DSO for symbol `%s' definition"),
4043 abfd, name);
4044 bfd_set_error (bfd_error_bad_value);
4045 goto error_free_vers;
4048 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4050 add_needed = TRUE;
4051 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4052 if (ret < 0)
4053 goto error_free_vers;
4055 BFD_ASSERT (ret == 0);
4060 /* Now that all the symbols from this input file are created, handle
4061 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4062 if (nondeflt_vers != NULL)
4064 bfd_size_type cnt, symidx;
4066 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4068 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4069 char *shortname, *p;
4071 p = strchr (h->root.root.string, ELF_VER_CHR);
4072 if (p == NULL
4073 || (h->root.type != bfd_link_hash_defined
4074 && h->root.type != bfd_link_hash_defweak))
4075 continue;
4077 amt = p - h->root.root.string;
4078 shortname = bfd_malloc (amt + 1);
4079 memcpy (shortname, h->root.root.string, amt);
4080 shortname[amt] = '\0';
4082 hi = (struct elf_link_hash_entry *)
4083 bfd_link_hash_lookup (&hash_table->root, shortname,
4084 FALSE, FALSE, FALSE);
4085 if (hi != NULL
4086 && hi->root.type == h->root.type
4087 && hi->root.u.def.value == h->root.u.def.value
4088 && hi->root.u.def.section == h->root.u.def.section)
4090 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4091 hi->root.type = bfd_link_hash_indirect;
4092 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4093 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
4094 sym_hash = elf_sym_hashes (abfd);
4095 if (sym_hash)
4096 for (symidx = 0; symidx < extsymcount; ++symidx)
4097 if (sym_hash[symidx] == hi)
4099 sym_hash[symidx] = h;
4100 break;
4103 free (shortname);
4105 free (nondeflt_vers);
4106 nondeflt_vers = NULL;
4109 if (extversym != NULL)
4111 free (extversym);
4112 extversym = NULL;
4115 if (isymbuf != NULL)
4116 free (isymbuf);
4117 isymbuf = NULL;
4119 if (!add_needed
4120 && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4122 /* Remove symbols defined in an as-needed shared lib that wasn't
4123 needed. */
4124 struct elf_smash_syms_data inf;
4125 inf.not_needed = abfd;
4126 inf.htab = hash_table;
4127 inf.twiddled = FALSE;
4128 elf_link_hash_traverse (hash_table, elf_smash_syms, &inf);
4129 if (inf.twiddled)
4130 bfd_link_repair_undef_list (&hash_table->root);
4131 weaks = NULL;
4134 /* Now set the weakdefs field correctly for all the weak defined
4135 symbols we found. The only way to do this is to search all the
4136 symbols. Since we only need the information for non functions in
4137 dynamic objects, that's the only time we actually put anything on
4138 the list WEAKS. We need this information so that if a regular
4139 object refers to a symbol defined weakly in a dynamic object, the
4140 real symbol in the dynamic object is also put in the dynamic
4141 symbols; we also must arrange for both symbols to point to the
4142 same memory location. We could handle the general case of symbol
4143 aliasing, but a general symbol alias can only be generated in
4144 assembler code, handling it correctly would be very time
4145 consuming, and other ELF linkers don't handle general aliasing
4146 either. */
4147 if (weaks != NULL)
4149 struct elf_link_hash_entry **hpp;
4150 struct elf_link_hash_entry **hppend;
4151 struct elf_link_hash_entry **sorted_sym_hash;
4152 struct elf_link_hash_entry *h;
4153 size_t sym_count;
4155 /* Since we have to search the whole symbol list for each weak
4156 defined symbol, search time for N weak defined symbols will be
4157 O(N^2). Binary search will cut it down to O(NlogN). */
4158 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4159 sorted_sym_hash = bfd_malloc (amt);
4160 if (sorted_sym_hash == NULL)
4161 goto error_return;
4162 sym_hash = sorted_sym_hash;
4163 hpp = elf_sym_hashes (abfd);
4164 hppend = hpp + extsymcount;
4165 sym_count = 0;
4166 for (; hpp < hppend; hpp++)
4168 h = *hpp;
4169 if (h != NULL
4170 && h->root.type == bfd_link_hash_defined
4171 && h->type != STT_FUNC)
4173 *sym_hash = h;
4174 sym_hash++;
4175 sym_count++;
4179 qsort (sorted_sym_hash, sym_count,
4180 sizeof (struct elf_link_hash_entry *),
4181 elf_sort_symbol);
4183 while (weaks != NULL)
4185 struct elf_link_hash_entry *hlook;
4186 asection *slook;
4187 bfd_vma vlook;
4188 long ilook;
4189 size_t i, j, idx;
4191 hlook = weaks;
4192 weaks = hlook->u.weakdef;
4193 hlook->u.weakdef = NULL;
4195 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4196 || hlook->root.type == bfd_link_hash_defweak
4197 || hlook->root.type == bfd_link_hash_common
4198 || hlook->root.type == bfd_link_hash_indirect);
4199 slook = hlook->root.u.def.section;
4200 vlook = hlook->root.u.def.value;
4202 ilook = -1;
4203 i = 0;
4204 j = sym_count;
4205 while (i < j)
4207 bfd_signed_vma vdiff;
4208 idx = (i + j) / 2;
4209 h = sorted_sym_hash [idx];
4210 vdiff = vlook - h->root.u.def.value;
4211 if (vdiff < 0)
4212 j = idx;
4213 else if (vdiff > 0)
4214 i = idx + 1;
4215 else
4217 long sdiff = slook->id - h->root.u.def.section->id;
4218 if (sdiff < 0)
4219 j = idx;
4220 else if (sdiff > 0)
4221 i = idx + 1;
4222 else
4224 ilook = idx;
4225 break;
4230 /* We didn't find a value/section match. */
4231 if (ilook == -1)
4232 continue;
4234 for (i = ilook; i < sym_count; i++)
4236 h = sorted_sym_hash [i];
4238 /* Stop if value or section doesn't match. */
4239 if (h->root.u.def.value != vlook
4240 || h->root.u.def.section != slook)
4241 break;
4242 else if (h != hlook)
4244 hlook->u.weakdef = h;
4246 /* If the weak definition is in the list of dynamic
4247 symbols, make sure the real definition is put
4248 there as well. */
4249 if (hlook->dynindx != -1 && h->dynindx == -1)
4251 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4252 goto error_return;
4255 /* If the real definition is in the list of dynamic
4256 symbols, make sure the weak definition is put
4257 there as well. If we don't do this, then the
4258 dynamic loader might not merge the entries for the
4259 real definition and the weak definition. */
4260 if (h->dynindx != -1 && hlook->dynindx == -1)
4262 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4263 goto error_return;
4265 break;
4270 free (sorted_sym_hash);
4273 check_directives = get_elf_backend_data (abfd)->check_directives;
4274 if (check_directives)
4275 check_directives (abfd, info);
4277 /* If this object is the same format as the output object, and it is
4278 not a shared library, then let the backend look through the
4279 relocs.
4281 This is required to build global offset table entries and to
4282 arrange for dynamic relocs. It is not required for the
4283 particular common case of linking non PIC code, even when linking
4284 against shared libraries, but unfortunately there is no way of
4285 knowing whether an object file has been compiled PIC or not.
4286 Looking through the relocs is not particularly time consuming.
4287 The problem is that we must either (1) keep the relocs in memory,
4288 which causes the linker to require additional runtime memory or
4289 (2) read the relocs twice from the input file, which wastes time.
4290 This would be a good case for using mmap.
4292 I have no idea how to handle linking PIC code into a file of a
4293 different format. It probably can't be done. */
4294 check_relocs = get_elf_backend_data (abfd)->check_relocs;
4295 if (! dynamic
4296 && is_elf_hash_table (hash_table)
4297 && hash_table->root.creator == abfd->xvec
4298 && check_relocs != NULL)
4300 asection *o;
4302 for (o = abfd->sections; o != NULL; o = o->next)
4304 Elf_Internal_Rela *internal_relocs;
4305 bfd_boolean ok;
4307 if ((o->flags & SEC_RELOC) == 0
4308 || o->reloc_count == 0
4309 || ((info->strip == strip_all || info->strip == strip_debugger)
4310 && (o->flags & SEC_DEBUGGING) != 0)
4311 || bfd_is_abs_section (o->output_section))
4312 continue;
4314 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4315 info->keep_memory);
4316 if (internal_relocs == NULL)
4317 goto error_return;
4319 ok = (*check_relocs) (abfd, info, o, internal_relocs);
4321 if (elf_section_data (o)->relocs != internal_relocs)
4322 free (internal_relocs);
4324 if (! ok)
4325 goto error_return;
4329 /* If this is a non-traditional link, try to optimize the handling
4330 of the .stab/.stabstr sections. */
4331 if (! dynamic
4332 && ! info->traditional_format
4333 && is_elf_hash_table (hash_table)
4334 && (info->strip != strip_all && info->strip != strip_debugger))
4336 asection *stabstr;
4338 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4339 if (stabstr != NULL)
4341 bfd_size_type string_offset = 0;
4342 asection *stab;
4344 for (stab = abfd->sections; stab; stab = stab->next)
4345 if (strncmp (".stab", stab->name, 5) == 0
4346 && (!stab->name[5] ||
4347 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4348 && (stab->flags & SEC_MERGE) == 0
4349 && !bfd_is_abs_section (stab->output_section))
4351 struct bfd_elf_section_data *secdata;
4353 secdata = elf_section_data (stab);
4354 if (! _bfd_link_section_stabs (abfd,
4355 &hash_table->stab_info,
4356 stab, stabstr,
4357 &secdata->sec_info,
4358 &string_offset))
4359 goto error_return;
4360 if (secdata->sec_info)
4361 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4366 if (is_elf_hash_table (hash_table) && add_needed)
4368 /* Add this bfd to the loaded list. */
4369 struct elf_link_loaded_list *n;
4371 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4372 if (n == NULL)
4373 goto error_return;
4374 n->abfd = abfd;
4375 n->next = hash_table->loaded;
4376 hash_table->loaded = n;
4379 return TRUE;
4381 error_free_vers:
4382 if (nondeflt_vers != NULL)
4383 free (nondeflt_vers);
4384 if (extversym != NULL)
4385 free (extversym);
4386 error_free_sym:
4387 if (isymbuf != NULL)
4388 free (isymbuf);
4389 error_return:
4390 return FALSE;
4393 /* Return the linker hash table entry of a symbol that might be
4394 satisfied by an archive symbol. Return -1 on error. */
4396 struct elf_link_hash_entry *
4397 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4398 struct bfd_link_info *info,
4399 const char *name)
4401 struct elf_link_hash_entry *h;
4402 char *p, *copy;
4403 size_t len, first;
4405 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4406 if (h != NULL)
4407 return h;
4409 /* If this is a default version (the name contains @@), look up the
4410 symbol again with only one `@' as well as without the version.
4411 The effect is that references to the symbol with and without the
4412 version will be matched by the default symbol in the archive. */
4414 p = strchr (name, ELF_VER_CHR);
4415 if (p == NULL || p[1] != ELF_VER_CHR)
4416 return h;
4418 /* First check with only one `@'. */
4419 len = strlen (name);
4420 copy = bfd_alloc (abfd, len);
4421 if (copy == NULL)
4422 return (struct elf_link_hash_entry *) 0 - 1;
4424 first = p - name + 1;
4425 memcpy (copy, name, first);
4426 memcpy (copy + first, name + first + 1, len - first);
4428 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4429 if (h == NULL)
4431 /* We also need to check references to the symbol without the
4432 version. */
4433 copy[first - 1] = '\0';
4434 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4435 FALSE, FALSE, FALSE);
4438 bfd_release (abfd, copy);
4439 return h;
4442 /* Add symbols from an ELF archive file to the linker hash table. We
4443 don't use _bfd_generic_link_add_archive_symbols because of a
4444 problem which arises on UnixWare. The UnixWare libc.so is an
4445 archive which includes an entry libc.so.1 which defines a bunch of
4446 symbols. The libc.so archive also includes a number of other
4447 object files, which also define symbols, some of which are the same
4448 as those defined in libc.so.1. Correct linking requires that we
4449 consider each object file in turn, and include it if it defines any
4450 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4451 this; it looks through the list of undefined symbols, and includes
4452 any object file which defines them. When this algorithm is used on
4453 UnixWare, it winds up pulling in libc.so.1 early and defining a
4454 bunch of symbols. This means that some of the other objects in the
4455 archive are not included in the link, which is incorrect since they
4456 precede libc.so.1 in the archive.
4458 Fortunately, ELF archive handling is simpler than that done by
4459 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4460 oddities. In ELF, if we find a symbol in the archive map, and the
4461 symbol is currently undefined, we know that we must pull in that
4462 object file.
4464 Unfortunately, we do have to make multiple passes over the symbol
4465 table until nothing further is resolved. */
4467 static bfd_boolean
4468 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4470 symindex c;
4471 bfd_boolean *defined = NULL;
4472 bfd_boolean *included = NULL;
4473 carsym *symdefs;
4474 bfd_boolean loop;
4475 bfd_size_type amt;
4476 const struct elf_backend_data *bed;
4477 struct elf_link_hash_entry * (*archive_symbol_lookup)
4478 (bfd *, struct bfd_link_info *, const char *);
4480 if (! bfd_has_map (abfd))
4482 /* An empty archive is a special case. */
4483 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4484 return TRUE;
4485 bfd_set_error (bfd_error_no_armap);
4486 return FALSE;
4489 /* Keep track of all symbols we know to be already defined, and all
4490 files we know to be already included. This is to speed up the
4491 second and subsequent passes. */
4492 c = bfd_ardata (abfd)->symdef_count;
4493 if (c == 0)
4494 return TRUE;
4495 amt = c;
4496 amt *= sizeof (bfd_boolean);
4497 defined = bfd_zmalloc (amt);
4498 included = bfd_zmalloc (amt);
4499 if (defined == NULL || included == NULL)
4500 goto error_return;
4502 symdefs = bfd_ardata (abfd)->symdefs;
4503 bed = get_elf_backend_data (abfd);
4504 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4508 file_ptr last;
4509 symindex i;
4510 carsym *symdef;
4511 carsym *symdefend;
4513 loop = FALSE;
4514 last = -1;
4516 symdef = symdefs;
4517 symdefend = symdef + c;
4518 for (i = 0; symdef < symdefend; symdef++, i++)
4520 struct elf_link_hash_entry *h;
4521 bfd *element;
4522 struct bfd_link_hash_entry *undefs_tail;
4523 symindex mark;
4525 if (defined[i] || included[i])
4526 continue;
4527 if (symdef->file_offset == last)
4529 included[i] = TRUE;
4530 continue;
4533 h = archive_symbol_lookup (abfd, info, symdef->name);
4534 if (h == (struct elf_link_hash_entry *) 0 - 1)
4535 goto error_return;
4537 if (h == NULL)
4538 continue;
4540 if (h->root.type == bfd_link_hash_common)
4542 /* We currently have a common symbol. The archive map contains
4543 a reference to this symbol, so we may want to include it. We
4544 only want to include it however, if this archive element
4545 contains a definition of the symbol, not just another common
4546 declaration of it.
4548 Unfortunately some archivers (including GNU ar) will put
4549 declarations of common symbols into their archive maps, as
4550 well as real definitions, so we cannot just go by the archive
4551 map alone. Instead we must read in the element's symbol
4552 table and check that to see what kind of symbol definition
4553 this is. */
4554 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4555 continue;
4557 else if (h->root.type != bfd_link_hash_undefined)
4559 if (h->root.type != bfd_link_hash_undefweak)
4560 defined[i] = TRUE;
4561 continue;
4564 /* We need to include this archive member. */
4565 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4566 if (element == NULL)
4567 goto error_return;
4569 if (! bfd_check_format (element, bfd_object))
4570 goto error_return;
4572 /* Doublecheck that we have not included this object
4573 already--it should be impossible, but there may be
4574 something wrong with the archive. */
4575 if (element->archive_pass != 0)
4577 bfd_set_error (bfd_error_bad_value);
4578 goto error_return;
4580 element->archive_pass = 1;
4582 undefs_tail = info->hash->undefs_tail;
4584 if (! (*info->callbacks->add_archive_element) (info, element,
4585 symdef->name))
4586 goto error_return;
4587 if (! bfd_link_add_symbols (element, info))
4588 goto error_return;
4590 /* If there are any new undefined symbols, we need to make
4591 another pass through the archive in order to see whether
4592 they can be defined. FIXME: This isn't perfect, because
4593 common symbols wind up on undefs_tail and because an
4594 undefined symbol which is defined later on in this pass
4595 does not require another pass. This isn't a bug, but it
4596 does make the code less efficient than it could be. */
4597 if (undefs_tail != info->hash->undefs_tail)
4598 loop = TRUE;
4600 /* Look backward to mark all symbols from this object file
4601 which we have already seen in this pass. */
4602 mark = i;
4605 included[mark] = TRUE;
4606 if (mark == 0)
4607 break;
4608 --mark;
4610 while (symdefs[mark].file_offset == symdef->file_offset);
4612 /* We mark subsequent symbols from this object file as we go
4613 on through the loop. */
4614 last = symdef->file_offset;
4617 while (loop);
4619 free (defined);
4620 free (included);
4622 return TRUE;
4624 error_return:
4625 if (defined != NULL)
4626 free (defined);
4627 if (included != NULL)
4628 free (included);
4629 return FALSE;
4632 /* Given an ELF BFD, add symbols to the global hash table as
4633 appropriate. */
4635 bfd_boolean
4636 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4638 switch (bfd_get_format (abfd))
4640 case bfd_object:
4641 return elf_link_add_object_symbols (abfd, info);
4642 case bfd_archive:
4643 return elf_link_add_archive_symbols (abfd, info);
4644 default:
4645 bfd_set_error (bfd_error_wrong_format);
4646 return FALSE;
4650 /* This function will be called though elf_link_hash_traverse to store
4651 all hash value of the exported symbols in an array. */
4653 static bfd_boolean
4654 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4656 unsigned long **valuep = data;
4657 const char *name;
4658 char *p;
4659 unsigned long ha;
4660 char *alc = NULL;
4662 if (h->root.type == bfd_link_hash_warning)
4663 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4665 /* Ignore indirect symbols. These are added by the versioning code. */
4666 if (h->dynindx == -1)
4667 return TRUE;
4669 name = h->root.root.string;
4670 p = strchr (name, ELF_VER_CHR);
4671 if (p != NULL)
4673 alc = bfd_malloc (p - name + 1);
4674 memcpy (alc, name, p - name);
4675 alc[p - name] = '\0';
4676 name = alc;
4679 /* Compute the hash value. */
4680 ha = bfd_elf_hash (name);
4682 /* Store the found hash value in the array given as the argument. */
4683 *(*valuep)++ = ha;
4685 /* And store it in the struct so that we can put it in the hash table
4686 later. */
4687 h->u.elf_hash_value = ha;
4689 if (alc != NULL)
4690 free (alc);
4692 return TRUE;
4695 /* Array used to determine the number of hash table buckets to use
4696 based on the number of symbols there are. If there are fewer than
4697 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4698 fewer than 37 we use 17 buckets, and so forth. We never use more
4699 than 32771 buckets. */
4701 static const size_t elf_buckets[] =
4703 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4704 16411, 32771, 0
4707 /* Compute bucket count for hashing table. We do not use a static set
4708 of possible tables sizes anymore. Instead we determine for all
4709 possible reasonable sizes of the table the outcome (i.e., the
4710 number of collisions etc) and choose the best solution. The
4711 weighting functions are not too simple to allow the table to grow
4712 without bounds. Instead one of the weighting factors is the size.
4713 Therefore the result is always a good payoff between few collisions
4714 (= short chain lengths) and table size. */
4715 static size_t
4716 compute_bucket_count (struct bfd_link_info *info)
4718 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4719 size_t best_size = 0;
4720 unsigned long int *hashcodes;
4721 unsigned long int *hashcodesp;
4722 unsigned long int i;
4723 bfd_size_type amt;
4725 /* Compute the hash values for all exported symbols. At the same
4726 time store the values in an array so that we could use them for
4727 optimizations. */
4728 amt = dynsymcount;
4729 amt *= sizeof (unsigned long int);
4730 hashcodes = bfd_malloc (amt);
4731 if (hashcodes == NULL)
4732 return 0;
4733 hashcodesp = hashcodes;
4735 /* Put all hash values in HASHCODES. */
4736 elf_link_hash_traverse (elf_hash_table (info),
4737 elf_collect_hash_codes, &hashcodesp);
4739 /* We have a problem here. The following code to optimize the table
4740 size requires an integer type with more the 32 bits. If
4741 BFD_HOST_U_64_BIT is set we know about such a type. */
4742 #ifdef BFD_HOST_U_64_BIT
4743 if (info->optimize)
4745 unsigned long int nsyms = hashcodesp - hashcodes;
4746 size_t minsize;
4747 size_t maxsize;
4748 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4749 unsigned long int *counts ;
4750 bfd *dynobj = elf_hash_table (info)->dynobj;
4751 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4753 /* Possible optimization parameters: if we have NSYMS symbols we say
4754 that the hashing table must at least have NSYMS/4 and at most
4755 2*NSYMS buckets. */
4756 minsize = nsyms / 4;
4757 if (minsize == 0)
4758 minsize = 1;
4759 best_size = maxsize = nsyms * 2;
4761 /* Create array where we count the collisions in. We must use bfd_malloc
4762 since the size could be large. */
4763 amt = maxsize;
4764 amt *= sizeof (unsigned long int);
4765 counts = bfd_malloc (amt);
4766 if (counts == NULL)
4768 free (hashcodes);
4769 return 0;
4772 /* Compute the "optimal" size for the hash table. The criteria is a
4773 minimal chain length. The minor criteria is (of course) the size
4774 of the table. */
4775 for (i = minsize; i < maxsize; ++i)
4777 /* Walk through the array of hashcodes and count the collisions. */
4778 BFD_HOST_U_64_BIT max;
4779 unsigned long int j;
4780 unsigned long int fact;
4782 memset (counts, '\0', i * sizeof (unsigned long int));
4784 /* Determine how often each hash bucket is used. */
4785 for (j = 0; j < nsyms; ++j)
4786 ++counts[hashcodes[j] % i];
4788 /* For the weight function we need some information about the
4789 pagesize on the target. This is information need not be 100%
4790 accurate. Since this information is not available (so far) we
4791 define it here to a reasonable default value. If it is crucial
4792 to have a better value some day simply define this value. */
4793 # ifndef BFD_TARGET_PAGESIZE
4794 # define BFD_TARGET_PAGESIZE (4096)
4795 # endif
4797 /* We in any case need 2 + NSYMS entries for the size values and
4798 the chains. */
4799 max = (2 + nsyms) * (bed->s->arch_size / 8);
4801 # if 1
4802 /* Variant 1: optimize for short chains. We add the squares
4803 of all the chain lengths (which favors many small chain
4804 over a few long chains). */
4805 for (j = 0; j < i; ++j)
4806 max += counts[j] * counts[j];
4808 /* This adds penalties for the overall size of the table. */
4809 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4810 max *= fact * fact;
4811 # else
4812 /* Variant 2: Optimize a lot more for small table. Here we
4813 also add squares of the size but we also add penalties for
4814 empty slots (the +1 term). */
4815 for (j = 0; j < i; ++j)
4816 max += (1 + counts[j]) * (1 + counts[j]);
4818 /* The overall size of the table is considered, but not as
4819 strong as in variant 1, where it is squared. */
4820 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4821 max *= fact;
4822 # endif
4824 /* Compare with current best results. */
4825 if (max < best_chlen)
4827 best_chlen = max;
4828 best_size = i;
4832 free (counts);
4834 else
4835 #endif /* defined (BFD_HOST_U_64_BIT) */
4837 /* This is the fallback solution if no 64bit type is available or if we
4838 are not supposed to spend much time on optimizations. We select the
4839 bucket count using a fixed set of numbers. */
4840 for (i = 0; elf_buckets[i] != 0; i++)
4842 best_size = elf_buckets[i];
4843 if (dynsymcount < elf_buckets[i + 1])
4844 break;
4848 /* Free the arrays we needed. */
4849 free (hashcodes);
4851 return best_size;
4854 /* Set up the sizes and contents of the ELF dynamic sections. This is
4855 called by the ELF linker emulation before_allocation routine. We
4856 must set the sizes of the sections before the linker sets the
4857 addresses of the various sections. */
4859 bfd_boolean
4860 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4861 const char *soname,
4862 const char *rpath,
4863 const char *filter_shlib,
4864 const char * const *auxiliary_filters,
4865 struct bfd_link_info *info,
4866 asection **sinterpptr,
4867 struct bfd_elf_version_tree *verdefs)
4869 bfd_size_type soname_indx;
4870 bfd *dynobj;
4871 const struct elf_backend_data *bed;
4872 struct elf_assign_sym_version_info asvinfo;
4874 *sinterpptr = NULL;
4876 soname_indx = (bfd_size_type) -1;
4878 if (!is_elf_hash_table (info->hash))
4879 return TRUE;
4881 elf_tdata (output_bfd)->relro = info->relro;
4882 if (info->execstack)
4883 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4884 else if (info->noexecstack)
4885 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4886 else
4888 bfd *inputobj;
4889 asection *notesec = NULL;
4890 int exec = 0;
4892 for (inputobj = info->input_bfds;
4893 inputobj;
4894 inputobj = inputobj->link_next)
4896 asection *s;
4898 if (inputobj->flags & DYNAMIC)
4899 continue;
4900 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
4901 if (s)
4903 if (s->flags & SEC_CODE)
4904 exec = PF_X;
4905 notesec = s;
4907 else
4908 exec = PF_X;
4910 if (notesec)
4912 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
4913 if (exec && info->relocatable
4914 && notesec->output_section != bfd_abs_section_ptr)
4915 notesec->output_section->flags |= SEC_CODE;
4919 /* Any syms created from now on start with -1 in
4920 got.refcount/offset and plt.refcount/offset. */
4921 elf_hash_table (info)->init_refcount = elf_hash_table (info)->init_offset;
4923 /* The backend may have to create some sections regardless of whether
4924 we're dynamic or not. */
4925 bed = get_elf_backend_data (output_bfd);
4926 if (bed->elf_backend_always_size_sections
4927 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
4928 return FALSE;
4930 dynobj = elf_hash_table (info)->dynobj;
4932 /* If there were no dynamic objects in the link, there is nothing to
4933 do here. */
4934 if (dynobj == NULL)
4935 return TRUE;
4937 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
4938 return FALSE;
4940 if (elf_hash_table (info)->dynamic_sections_created)
4942 struct elf_info_failed eif;
4943 struct elf_link_hash_entry *h;
4944 asection *dynstr;
4945 struct bfd_elf_version_tree *t;
4946 struct bfd_elf_version_expr *d;
4947 bfd_boolean all_defined;
4949 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
4950 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
4952 if (soname != NULL)
4954 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
4955 soname, TRUE);
4956 if (soname_indx == (bfd_size_type) -1
4957 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
4958 return FALSE;
4961 if (info->symbolic)
4963 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
4964 return FALSE;
4965 info->flags |= DF_SYMBOLIC;
4968 if (rpath != NULL)
4970 bfd_size_type indx;
4972 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
4973 TRUE);
4974 if (indx == (bfd_size_type) -1
4975 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
4976 return FALSE;
4978 if (info->new_dtags)
4980 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
4981 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
4982 return FALSE;
4986 if (filter_shlib != NULL)
4988 bfd_size_type indx;
4990 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
4991 filter_shlib, TRUE);
4992 if (indx == (bfd_size_type) -1
4993 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
4994 return FALSE;
4997 if (auxiliary_filters != NULL)
4999 const char * const *p;
5001 for (p = auxiliary_filters; *p != NULL; p++)
5003 bfd_size_type indx;
5005 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5006 *p, TRUE);
5007 if (indx == (bfd_size_type) -1
5008 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5009 return FALSE;
5013 eif.info = info;
5014 eif.verdefs = verdefs;
5015 eif.failed = FALSE;
5017 /* If we are supposed to export all symbols into the dynamic symbol
5018 table (this is not the normal case), then do so. */
5019 if (info->export_dynamic)
5021 elf_link_hash_traverse (elf_hash_table (info),
5022 _bfd_elf_export_symbol,
5023 &eif);
5024 if (eif.failed)
5025 return FALSE;
5028 /* Make all global versions with definition. */
5029 for (t = verdefs; t != NULL; t = t->next)
5030 for (d = t->globals.list; d != NULL; d = d->next)
5031 if (!d->symver && d->symbol)
5033 const char *verstr, *name;
5034 size_t namelen, verlen, newlen;
5035 char *newname, *p;
5036 struct elf_link_hash_entry *newh;
5038 name = d->symbol;
5039 namelen = strlen (name);
5040 verstr = t->name;
5041 verlen = strlen (verstr);
5042 newlen = namelen + verlen + 3;
5044 newname = bfd_malloc (newlen);
5045 if (newname == NULL)
5046 return FALSE;
5047 memcpy (newname, name, namelen);
5049 /* Check the hidden versioned definition. */
5050 p = newname + namelen;
5051 *p++ = ELF_VER_CHR;
5052 memcpy (p, verstr, verlen + 1);
5053 newh = elf_link_hash_lookup (elf_hash_table (info),
5054 newname, FALSE, FALSE,
5055 FALSE);
5056 if (newh == NULL
5057 || (newh->root.type != bfd_link_hash_defined
5058 && newh->root.type != bfd_link_hash_defweak))
5060 /* Check the default versioned definition. */
5061 *p++ = ELF_VER_CHR;
5062 memcpy (p, verstr, verlen + 1);
5063 newh = elf_link_hash_lookup (elf_hash_table (info),
5064 newname, FALSE, FALSE,
5065 FALSE);
5067 free (newname);
5069 /* Mark this version if there is a definition and it is
5070 not defined in a shared object. */
5071 if (newh != NULL
5072 && !newh->def_dynamic
5073 && (newh->root.type == bfd_link_hash_defined
5074 || newh->root.type == bfd_link_hash_defweak))
5075 d->symver = 1;
5078 /* Attach all the symbols to their version information. */
5079 asvinfo.output_bfd = output_bfd;
5080 asvinfo.info = info;
5081 asvinfo.verdefs = verdefs;
5082 asvinfo.failed = FALSE;
5084 elf_link_hash_traverse (elf_hash_table (info),
5085 _bfd_elf_link_assign_sym_version,
5086 &asvinfo);
5087 if (asvinfo.failed)
5088 return FALSE;
5090 if (!info->allow_undefined_version)
5092 /* Check if all global versions have a definition. */
5093 all_defined = TRUE;
5094 for (t = verdefs; t != NULL; t = t->next)
5095 for (d = t->globals.list; d != NULL; d = d->next)
5096 if (!d->symver && !d->script)
5098 (*_bfd_error_handler)
5099 (_("%s: undefined version: %s"),
5100 d->pattern, t->name);
5101 all_defined = FALSE;
5104 if (!all_defined)
5106 bfd_set_error (bfd_error_bad_value);
5107 return FALSE;
5111 /* Find all symbols which were defined in a dynamic object and make
5112 the backend pick a reasonable value for them. */
5113 elf_link_hash_traverse (elf_hash_table (info),
5114 _bfd_elf_adjust_dynamic_symbol,
5115 &eif);
5116 if (eif.failed)
5117 return FALSE;
5119 /* Add some entries to the .dynamic section. We fill in some of the
5120 values later, in bfd_elf_final_link, but we must add the entries
5121 now so that we know the final size of the .dynamic section. */
5123 /* If there are initialization and/or finalization functions to
5124 call then add the corresponding DT_INIT/DT_FINI entries. */
5125 h = (info->init_function
5126 ? elf_link_hash_lookup (elf_hash_table (info),
5127 info->init_function, FALSE,
5128 FALSE, FALSE)
5129 : NULL);
5130 if (h != NULL
5131 && (h->ref_regular
5132 || h->def_regular))
5134 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5135 return FALSE;
5137 h = (info->fini_function
5138 ? elf_link_hash_lookup (elf_hash_table (info),
5139 info->fini_function, FALSE,
5140 FALSE, FALSE)
5141 : NULL);
5142 if (h != NULL
5143 && (h->ref_regular
5144 || h->def_regular))
5146 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5147 return FALSE;
5150 if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL)
5152 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5153 if (! info->executable)
5155 bfd *sub;
5156 asection *o;
5158 for (sub = info->input_bfds; sub != NULL;
5159 sub = sub->link_next)
5160 for (o = sub->sections; o != NULL; o = o->next)
5161 if (elf_section_data (o)->this_hdr.sh_type
5162 == SHT_PREINIT_ARRAY)
5164 (*_bfd_error_handler)
5165 (_("%B: .preinit_array section is not allowed in DSO"),
5166 sub);
5167 break;
5170 bfd_set_error (bfd_error_nonrepresentable_section);
5171 return FALSE;
5174 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5175 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5176 return FALSE;
5178 if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL)
5180 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5181 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5182 return FALSE;
5184 if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL)
5186 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5187 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5188 return FALSE;
5191 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5192 /* If .dynstr is excluded from the link, we don't want any of
5193 these tags. Strictly, we should be checking each section
5194 individually; This quick check covers for the case where
5195 someone does a /DISCARD/ : { *(*) }. */
5196 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5198 bfd_size_type strsize;
5200 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5201 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
5202 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5203 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5204 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5205 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5206 bed->s->sizeof_sym))
5207 return FALSE;
5211 /* The backend must work out the sizes of all the other dynamic
5212 sections. */
5213 if (bed->elf_backend_size_dynamic_sections
5214 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5215 return FALSE;
5217 if (elf_hash_table (info)->dynamic_sections_created)
5219 bfd_size_type dynsymcount;
5220 asection *s;
5221 size_t bucketcount = 0;
5222 size_t hash_entry_size;
5223 unsigned int dtagcount;
5225 /* Set up the version definition section. */
5226 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5227 BFD_ASSERT (s != NULL);
5229 /* We may have created additional version definitions if we are
5230 just linking a regular application. */
5231 verdefs = asvinfo.verdefs;
5233 /* Skip anonymous version tag. */
5234 if (verdefs != NULL && verdefs->vernum == 0)
5235 verdefs = verdefs->next;
5237 if (verdefs == NULL && !info->create_default_symver)
5238 _bfd_strip_section_from_output (info, s);
5239 else
5241 unsigned int cdefs;
5242 bfd_size_type size;
5243 struct bfd_elf_version_tree *t;
5244 bfd_byte *p;
5245 Elf_Internal_Verdef def;
5246 Elf_Internal_Verdaux defaux;
5247 struct bfd_link_hash_entry *bh;
5248 struct elf_link_hash_entry *h;
5249 const char *name;
5251 cdefs = 0;
5252 size = 0;
5254 /* Make space for the base version. */
5255 size += sizeof (Elf_External_Verdef);
5256 size += sizeof (Elf_External_Verdaux);
5257 ++cdefs;
5259 /* Make space for the default version. */
5260 if (info->create_default_symver)
5262 size += sizeof (Elf_External_Verdef);
5263 ++cdefs;
5266 for (t = verdefs; t != NULL; t = t->next)
5268 struct bfd_elf_version_deps *n;
5270 size += sizeof (Elf_External_Verdef);
5271 size += sizeof (Elf_External_Verdaux);
5272 ++cdefs;
5274 for (n = t->deps; n != NULL; n = n->next)
5275 size += sizeof (Elf_External_Verdaux);
5278 s->size = size;
5279 s->contents = bfd_alloc (output_bfd, s->size);
5280 if (s->contents == NULL && s->size != 0)
5281 return FALSE;
5283 /* Fill in the version definition section. */
5285 p = s->contents;
5287 def.vd_version = VER_DEF_CURRENT;
5288 def.vd_flags = VER_FLG_BASE;
5289 def.vd_ndx = 1;
5290 def.vd_cnt = 1;
5291 if (info->create_default_symver)
5293 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5294 def.vd_next = sizeof (Elf_External_Verdef);
5296 else
5298 def.vd_aux = sizeof (Elf_External_Verdef);
5299 def.vd_next = (sizeof (Elf_External_Verdef)
5300 + sizeof (Elf_External_Verdaux));
5303 if (soname_indx != (bfd_size_type) -1)
5305 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5306 soname_indx);
5307 def.vd_hash = bfd_elf_hash (soname);
5308 defaux.vda_name = soname_indx;
5309 name = soname;
5311 else
5313 bfd_size_type indx;
5315 name = basename (output_bfd->filename);
5316 def.vd_hash = bfd_elf_hash (name);
5317 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5318 name, FALSE);
5319 if (indx == (bfd_size_type) -1)
5320 return FALSE;
5321 defaux.vda_name = indx;
5323 defaux.vda_next = 0;
5325 _bfd_elf_swap_verdef_out (output_bfd, &def,
5326 (Elf_External_Verdef *) p);
5327 p += sizeof (Elf_External_Verdef);
5328 if (info->create_default_symver)
5330 /* Add a symbol representing this version. */
5331 bh = NULL;
5332 if (! (_bfd_generic_link_add_one_symbol
5333 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5334 0, NULL, FALSE,
5335 get_elf_backend_data (dynobj)->collect, &bh)))
5336 return FALSE;
5337 h = (struct elf_link_hash_entry *) bh;
5338 h->non_elf = 0;
5339 h->def_regular = 1;
5340 h->type = STT_OBJECT;
5341 h->verinfo.vertree = NULL;
5343 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5344 return FALSE;
5346 /* Create a duplicate of the base version with the same
5347 aux block, but different flags. */
5348 def.vd_flags = 0;
5349 def.vd_ndx = 2;
5350 def.vd_aux = sizeof (Elf_External_Verdef);
5351 if (verdefs)
5352 def.vd_next = (sizeof (Elf_External_Verdef)
5353 + sizeof (Elf_External_Verdaux));
5354 else
5355 def.vd_next = 0;
5356 _bfd_elf_swap_verdef_out (output_bfd, &def,
5357 (Elf_External_Verdef *) p);
5358 p += sizeof (Elf_External_Verdef);
5360 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5361 (Elf_External_Verdaux *) p);
5362 p += sizeof (Elf_External_Verdaux);
5364 for (t = verdefs; t != NULL; t = t->next)
5366 unsigned int cdeps;
5367 struct bfd_elf_version_deps *n;
5369 cdeps = 0;
5370 for (n = t->deps; n != NULL; n = n->next)
5371 ++cdeps;
5373 /* Add a symbol representing this version. */
5374 bh = NULL;
5375 if (! (_bfd_generic_link_add_one_symbol
5376 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5377 0, NULL, FALSE,
5378 get_elf_backend_data (dynobj)->collect, &bh)))
5379 return FALSE;
5380 h = (struct elf_link_hash_entry *) bh;
5381 h->non_elf = 0;
5382 h->def_regular = 1;
5383 h->type = STT_OBJECT;
5384 h->verinfo.vertree = t;
5386 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5387 return FALSE;
5389 def.vd_version = VER_DEF_CURRENT;
5390 def.vd_flags = 0;
5391 if (t->globals.list == NULL
5392 && t->locals.list == NULL
5393 && ! t->used)
5394 def.vd_flags |= VER_FLG_WEAK;
5395 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5396 def.vd_cnt = cdeps + 1;
5397 def.vd_hash = bfd_elf_hash (t->name);
5398 def.vd_aux = sizeof (Elf_External_Verdef);
5399 def.vd_next = 0;
5400 if (t->next != NULL)
5401 def.vd_next = (sizeof (Elf_External_Verdef)
5402 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5404 _bfd_elf_swap_verdef_out (output_bfd, &def,
5405 (Elf_External_Verdef *) p);
5406 p += sizeof (Elf_External_Verdef);
5408 defaux.vda_name = h->dynstr_index;
5409 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5410 h->dynstr_index);
5411 defaux.vda_next = 0;
5412 if (t->deps != NULL)
5413 defaux.vda_next = sizeof (Elf_External_Verdaux);
5414 t->name_indx = defaux.vda_name;
5416 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5417 (Elf_External_Verdaux *) p);
5418 p += sizeof (Elf_External_Verdaux);
5420 for (n = t->deps; n != NULL; n = n->next)
5422 if (n->version_needed == NULL)
5424 /* This can happen if there was an error in the
5425 version script. */
5426 defaux.vda_name = 0;
5428 else
5430 defaux.vda_name = n->version_needed->name_indx;
5431 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5432 defaux.vda_name);
5434 if (n->next == NULL)
5435 defaux.vda_next = 0;
5436 else
5437 defaux.vda_next = sizeof (Elf_External_Verdaux);
5439 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5440 (Elf_External_Verdaux *) p);
5441 p += sizeof (Elf_External_Verdaux);
5445 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5446 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5447 return FALSE;
5449 elf_tdata (output_bfd)->cverdefs = cdefs;
5452 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5454 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5455 return FALSE;
5457 else if (info->flags & DF_BIND_NOW)
5459 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5460 return FALSE;
5463 if (info->flags_1)
5465 if (info->executable)
5466 info->flags_1 &= ~ (DF_1_INITFIRST
5467 | DF_1_NODELETE
5468 | DF_1_NOOPEN);
5469 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5470 return FALSE;
5473 /* Work out the size of the version reference section. */
5475 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5476 BFD_ASSERT (s != NULL);
5478 struct elf_find_verdep_info sinfo;
5480 sinfo.output_bfd = output_bfd;
5481 sinfo.info = info;
5482 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5483 if (sinfo.vers == 0)
5484 sinfo.vers = 1;
5485 sinfo.failed = FALSE;
5487 elf_link_hash_traverse (elf_hash_table (info),
5488 _bfd_elf_link_find_version_dependencies,
5489 &sinfo);
5491 if (elf_tdata (output_bfd)->verref == NULL)
5492 _bfd_strip_section_from_output (info, s);
5493 else
5495 Elf_Internal_Verneed *t;
5496 unsigned int size;
5497 unsigned int crefs;
5498 bfd_byte *p;
5500 /* Build the version definition section. */
5501 size = 0;
5502 crefs = 0;
5503 for (t = elf_tdata (output_bfd)->verref;
5504 t != NULL;
5505 t = t->vn_nextref)
5507 Elf_Internal_Vernaux *a;
5509 size += sizeof (Elf_External_Verneed);
5510 ++crefs;
5511 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5512 size += sizeof (Elf_External_Vernaux);
5515 s->size = size;
5516 s->contents = bfd_alloc (output_bfd, s->size);
5517 if (s->contents == NULL)
5518 return FALSE;
5520 p = s->contents;
5521 for (t = elf_tdata (output_bfd)->verref;
5522 t != NULL;
5523 t = t->vn_nextref)
5525 unsigned int caux;
5526 Elf_Internal_Vernaux *a;
5527 bfd_size_type indx;
5529 caux = 0;
5530 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5531 ++caux;
5533 t->vn_version = VER_NEED_CURRENT;
5534 t->vn_cnt = caux;
5535 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5536 elf_dt_name (t->vn_bfd) != NULL
5537 ? elf_dt_name (t->vn_bfd)
5538 : basename (t->vn_bfd->filename),
5539 FALSE);
5540 if (indx == (bfd_size_type) -1)
5541 return FALSE;
5542 t->vn_file = indx;
5543 t->vn_aux = sizeof (Elf_External_Verneed);
5544 if (t->vn_nextref == NULL)
5545 t->vn_next = 0;
5546 else
5547 t->vn_next = (sizeof (Elf_External_Verneed)
5548 + caux * sizeof (Elf_External_Vernaux));
5550 _bfd_elf_swap_verneed_out (output_bfd, t,
5551 (Elf_External_Verneed *) p);
5552 p += sizeof (Elf_External_Verneed);
5554 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5556 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5557 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5558 a->vna_nodename, FALSE);
5559 if (indx == (bfd_size_type) -1)
5560 return FALSE;
5561 a->vna_name = indx;
5562 if (a->vna_nextptr == NULL)
5563 a->vna_next = 0;
5564 else
5565 a->vna_next = sizeof (Elf_External_Vernaux);
5567 _bfd_elf_swap_vernaux_out (output_bfd, a,
5568 (Elf_External_Vernaux *) p);
5569 p += sizeof (Elf_External_Vernaux);
5573 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5574 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5575 return FALSE;
5577 elf_tdata (output_bfd)->cverrefs = crefs;
5581 /* Assign dynsym indicies. In a shared library we generate a
5582 section symbol for each output section, which come first.
5583 Next come all of the back-end allocated local dynamic syms,
5584 followed by the rest of the global symbols. */
5586 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5588 /* Work out the size of the symbol version section. */
5589 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5590 BFD_ASSERT (s != NULL);
5591 if (dynsymcount == 0
5592 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL
5593 && !info->create_default_symver))
5595 _bfd_strip_section_from_output (info, s);
5596 /* The DYNSYMCOUNT might have changed if we were going to
5597 output a dynamic symbol table entry for S. */
5598 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5600 else
5602 s->size = dynsymcount * sizeof (Elf_External_Versym);
5603 s->contents = bfd_zalloc (output_bfd, s->size);
5604 if (s->contents == NULL)
5605 return FALSE;
5607 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5608 return FALSE;
5611 /* Set the size of the .dynsym and .hash sections. We counted
5612 the number of dynamic symbols in elf_link_add_object_symbols.
5613 We will build the contents of .dynsym and .hash when we build
5614 the final symbol table, because until then we do not know the
5615 correct value to give the symbols. We built the .dynstr
5616 section as we went along in elf_link_add_object_symbols. */
5617 s = bfd_get_section_by_name (dynobj, ".dynsym");
5618 BFD_ASSERT (s != NULL);
5619 s->size = dynsymcount * bed->s->sizeof_sym;
5620 s->contents = bfd_alloc (output_bfd, s->size);
5621 if (s->contents == NULL && s->size != 0)
5622 return FALSE;
5624 if (dynsymcount != 0)
5626 Elf_Internal_Sym isym;
5628 /* The first entry in .dynsym is a dummy symbol. */
5629 isym.st_value = 0;
5630 isym.st_size = 0;
5631 isym.st_name = 0;
5632 isym.st_info = 0;
5633 isym.st_other = 0;
5634 isym.st_shndx = 0;
5635 bed->s->swap_symbol_out (output_bfd, &isym, s->contents, 0);
5638 /* Compute the size of the hashing table. As a side effect this
5639 computes the hash values for all the names we export. */
5640 bucketcount = compute_bucket_count (info);
5642 s = bfd_get_section_by_name (dynobj, ".hash");
5643 BFD_ASSERT (s != NULL);
5644 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5645 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5646 s->contents = bfd_zalloc (output_bfd, s->size);
5647 if (s->contents == NULL)
5648 return FALSE;
5650 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5651 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5652 s->contents + hash_entry_size);
5654 elf_hash_table (info)->bucketcount = bucketcount;
5656 s = bfd_get_section_by_name (dynobj, ".dynstr");
5657 BFD_ASSERT (s != NULL);
5659 elf_finalize_dynstr (output_bfd, info);
5661 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5663 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5664 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5665 return FALSE;
5668 return TRUE;
5671 /* Final phase of ELF linker. */
5673 /* A structure we use to avoid passing large numbers of arguments. */
5675 struct elf_final_link_info
5677 /* General link information. */
5678 struct bfd_link_info *info;
5679 /* Output BFD. */
5680 bfd *output_bfd;
5681 /* Symbol string table. */
5682 struct bfd_strtab_hash *symstrtab;
5683 /* .dynsym section. */
5684 asection *dynsym_sec;
5685 /* .hash section. */
5686 asection *hash_sec;
5687 /* symbol version section (.gnu.version). */
5688 asection *symver_sec;
5689 /* Buffer large enough to hold contents of any section. */
5690 bfd_byte *contents;
5691 /* Buffer large enough to hold external relocs of any section. */
5692 void *external_relocs;
5693 /* Buffer large enough to hold internal relocs of any section. */
5694 Elf_Internal_Rela *internal_relocs;
5695 /* Buffer large enough to hold external local symbols of any input
5696 BFD. */
5697 bfd_byte *external_syms;
5698 /* And a buffer for symbol section indices. */
5699 Elf_External_Sym_Shndx *locsym_shndx;
5700 /* Buffer large enough to hold internal local symbols of any input
5701 BFD. */
5702 Elf_Internal_Sym *internal_syms;
5703 /* Array large enough to hold a symbol index for each local symbol
5704 of any input BFD. */
5705 long *indices;
5706 /* Array large enough to hold a section pointer for each local
5707 symbol of any input BFD. */
5708 asection **sections;
5709 /* Buffer to hold swapped out symbols. */
5710 bfd_byte *symbuf;
5711 /* And one for symbol section indices. */
5712 Elf_External_Sym_Shndx *symshndxbuf;
5713 /* Number of swapped out symbols in buffer. */
5714 size_t symbuf_count;
5715 /* Number of symbols which fit in symbuf. */
5716 size_t symbuf_size;
5717 /* And same for symshndxbuf. */
5718 size_t shndxbuf_size;
5721 /* This struct is used to pass information to elf_link_output_extsym. */
5723 struct elf_outext_info
5725 bfd_boolean failed;
5726 bfd_boolean localsyms;
5727 struct elf_final_link_info *finfo;
5730 /* When performing a relocatable link, the input relocations are
5731 preserved. But, if they reference global symbols, the indices
5732 referenced must be updated. Update all the relocations in
5733 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5735 static void
5736 elf_link_adjust_relocs (bfd *abfd,
5737 Elf_Internal_Shdr *rel_hdr,
5738 unsigned int count,
5739 struct elf_link_hash_entry **rel_hash)
5741 unsigned int i;
5742 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5743 bfd_byte *erela;
5744 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5745 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5746 bfd_vma r_type_mask;
5747 int r_sym_shift;
5749 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5751 swap_in = bed->s->swap_reloc_in;
5752 swap_out = bed->s->swap_reloc_out;
5754 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5756 swap_in = bed->s->swap_reloca_in;
5757 swap_out = bed->s->swap_reloca_out;
5759 else
5760 abort ();
5762 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5763 abort ();
5765 if (bed->s->arch_size == 32)
5767 r_type_mask = 0xff;
5768 r_sym_shift = 8;
5770 else
5772 r_type_mask = 0xffffffff;
5773 r_sym_shift = 32;
5776 erela = rel_hdr->contents;
5777 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5779 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5780 unsigned int j;
5782 if (*rel_hash == NULL)
5783 continue;
5785 BFD_ASSERT ((*rel_hash)->indx >= 0);
5787 (*swap_in) (abfd, erela, irela);
5788 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5789 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5790 | (irela[j].r_info & r_type_mask));
5791 (*swap_out) (abfd, irela, erela);
5795 struct elf_link_sort_rela
5797 union {
5798 bfd_vma offset;
5799 bfd_vma sym_mask;
5800 } u;
5801 enum elf_reloc_type_class type;
5802 /* We use this as an array of size int_rels_per_ext_rel. */
5803 Elf_Internal_Rela rela[1];
5806 static int
5807 elf_link_sort_cmp1 (const void *A, const void *B)
5809 const struct elf_link_sort_rela *a = A;
5810 const struct elf_link_sort_rela *b = B;
5811 int relativea, relativeb;
5813 relativea = a->type == reloc_class_relative;
5814 relativeb = b->type == reloc_class_relative;
5816 if (relativea < relativeb)
5817 return 1;
5818 if (relativea > relativeb)
5819 return -1;
5820 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5821 return -1;
5822 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5823 return 1;
5824 if (a->rela->r_offset < b->rela->r_offset)
5825 return -1;
5826 if (a->rela->r_offset > b->rela->r_offset)
5827 return 1;
5828 return 0;
5831 static int
5832 elf_link_sort_cmp2 (const void *A, const void *B)
5834 const struct elf_link_sort_rela *a = A;
5835 const struct elf_link_sort_rela *b = B;
5836 int copya, copyb;
5838 if (a->u.offset < b->u.offset)
5839 return -1;
5840 if (a->u.offset > b->u.offset)
5841 return 1;
5842 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5843 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5844 if (copya < copyb)
5845 return -1;
5846 if (copya > copyb)
5847 return 1;
5848 if (a->rela->r_offset < b->rela->r_offset)
5849 return -1;
5850 if (a->rela->r_offset > b->rela->r_offset)
5851 return 1;
5852 return 0;
5855 static size_t
5856 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5858 asection *reldyn;
5859 bfd_size_type count, size;
5860 size_t i, ret, sort_elt, ext_size;
5861 bfd_byte *sort, *s_non_relative, *p;
5862 struct elf_link_sort_rela *sq;
5863 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5864 int i2e = bed->s->int_rels_per_ext_rel;
5865 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5866 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5867 struct bfd_link_order *lo;
5868 bfd_vma r_sym_mask;
5870 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5871 if (reldyn == NULL || reldyn->size == 0)
5873 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
5874 if (reldyn == NULL || reldyn->size == 0)
5875 return 0;
5876 ext_size = bed->s->sizeof_rel;
5877 swap_in = bed->s->swap_reloc_in;
5878 swap_out = bed->s->swap_reloc_out;
5880 else
5882 ext_size = bed->s->sizeof_rela;
5883 swap_in = bed->s->swap_reloca_in;
5884 swap_out = bed->s->swap_reloca_out;
5886 count = reldyn->size / ext_size;
5888 size = 0;
5889 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5890 if (lo->type == bfd_indirect_link_order)
5892 asection *o = lo->u.indirect.section;
5893 size += o->size;
5896 if (size != reldyn->size)
5897 return 0;
5899 sort_elt = (sizeof (struct elf_link_sort_rela)
5900 + (i2e - 1) * sizeof (Elf_Internal_Rela));
5901 sort = bfd_zmalloc (sort_elt * count);
5902 if (sort == NULL)
5904 (*info->callbacks->warning)
5905 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
5906 return 0;
5909 if (bed->s->arch_size == 32)
5910 r_sym_mask = ~(bfd_vma) 0xff;
5911 else
5912 r_sym_mask = ~(bfd_vma) 0xffffffff;
5914 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5915 if (lo->type == bfd_indirect_link_order)
5917 bfd_byte *erel, *erelend;
5918 asection *o = lo->u.indirect.section;
5920 if (o->contents == NULL && o->size != 0)
5922 /* This is a reloc section that is being handled as a normal
5923 section. See bfd_section_from_shdr. We can't combine
5924 relocs in this case. */
5925 free (sort);
5926 return 0;
5928 erel = o->contents;
5929 erelend = o->contents + o->size;
5930 p = sort + o->output_offset / ext_size * sort_elt;
5931 while (erel < erelend)
5933 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5934 (*swap_in) (abfd, erel, s->rela);
5935 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
5936 s->u.sym_mask = r_sym_mask;
5937 p += sort_elt;
5938 erel += ext_size;
5942 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
5944 for (i = 0, p = sort; i < count; i++, p += sort_elt)
5946 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5947 if (s->type != reloc_class_relative)
5948 break;
5950 ret = i;
5951 s_non_relative = p;
5953 sq = (struct elf_link_sort_rela *) s_non_relative;
5954 for (; i < count; i++, p += sort_elt)
5956 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
5957 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
5958 sq = sp;
5959 sp->u.offset = sq->rela->r_offset;
5962 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
5964 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5965 if (lo->type == bfd_indirect_link_order)
5967 bfd_byte *erel, *erelend;
5968 asection *o = lo->u.indirect.section;
5970 erel = o->contents;
5971 erelend = o->contents + o->size;
5972 p = sort + o->output_offset / ext_size * sort_elt;
5973 while (erel < erelend)
5975 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5976 (*swap_out) (abfd, s->rela, erel);
5977 p += sort_elt;
5978 erel += ext_size;
5982 free (sort);
5983 *psec = reldyn;
5984 return ret;
5987 /* Flush the output symbols to the file. */
5989 static bfd_boolean
5990 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
5991 const struct elf_backend_data *bed)
5993 if (finfo->symbuf_count > 0)
5995 Elf_Internal_Shdr *hdr;
5996 file_ptr pos;
5997 bfd_size_type amt;
5999 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6000 pos = hdr->sh_offset + hdr->sh_size;
6001 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6002 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6003 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6004 return FALSE;
6006 hdr->sh_size += amt;
6007 finfo->symbuf_count = 0;
6010 return TRUE;
6013 /* Add a symbol to the output symbol table. */
6015 static bfd_boolean
6016 elf_link_output_sym (struct elf_final_link_info *finfo,
6017 const char *name,
6018 Elf_Internal_Sym *elfsym,
6019 asection *input_sec,
6020 struct elf_link_hash_entry *h)
6022 bfd_byte *dest;
6023 Elf_External_Sym_Shndx *destshndx;
6024 bfd_boolean (*output_symbol_hook)
6025 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6026 struct elf_link_hash_entry *);
6027 const struct elf_backend_data *bed;
6029 bed = get_elf_backend_data (finfo->output_bfd);
6030 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6031 if (output_symbol_hook != NULL)
6033 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6034 return FALSE;
6037 if (name == NULL || *name == '\0')
6038 elfsym->st_name = 0;
6039 else if (input_sec->flags & SEC_EXCLUDE)
6040 elfsym->st_name = 0;
6041 else
6043 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6044 name, TRUE, FALSE);
6045 if (elfsym->st_name == (unsigned long) -1)
6046 return FALSE;
6049 if (finfo->symbuf_count >= finfo->symbuf_size)
6051 if (! elf_link_flush_output_syms (finfo, bed))
6052 return FALSE;
6055 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6056 destshndx = finfo->symshndxbuf;
6057 if (destshndx != NULL)
6059 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6061 bfd_size_type amt;
6063 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6064 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6065 if (destshndx == NULL)
6066 return FALSE;
6067 memset ((char *) destshndx + amt, 0, amt);
6068 finfo->shndxbuf_size *= 2;
6070 destshndx += bfd_get_symcount (finfo->output_bfd);
6073 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6074 finfo->symbuf_count += 1;
6075 bfd_get_symcount (finfo->output_bfd) += 1;
6077 return TRUE;
6080 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6081 allowing an unsatisfied unversioned symbol in the DSO to match a
6082 versioned symbol that would normally require an explicit version.
6083 We also handle the case that a DSO references a hidden symbol
6084 which may be satisfied by a versioned symbol in another DSO. */
6086 static bfd_boolean
6087 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6088 const struct elf_backend_data *bed,
6089 struct elf_link_hash_entry *h)
6091 bfd *abfd;
6092 struct elf_link_loaded_list *loaded;
6094 if (!is_elf_hash_table (info->hash))
6095 return FALSE;
6097 switch (h->root.type)
6099 default:
6100 abfd = NULL;
6101 break;
6103 case bfd_link_hash_undefined:
6104 case bfd_link_hash_undefweak:
6105 abfd = h->root.u.undef.abfd;
6106 if ((abfd->flags & DYNAMIC) == 0
6107 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6108 return FALSE;
6109 break;
6111 case bfd_link_hash_defined:
6112 case bfd_link_hash_defweak:
6113 abfd = h->root.u.def.section->owner;
6114 break;
6116 case bfd_link_hash_common:
6117 abfd = h->root.u.c.p->section->owner;
6118 break;
6120 BFD_ASSERT (abfd != NULL);
6122 for (loaded = elf_hash_table (info)->loaded;
6123 loaded != NULL;
6124 loaded = loaded->next)
6126 bfd *input;
6127 Elf_Internal_Shdr *hdr;
6128 bfd_size_type symcount;
6129 bfd_size_type extsymcount;
6130 bfd_size_type extsymoff;
6131 Elf_Internal_Shdr *versymhdr;
6132 Elf_Internal_Sym *isym;
6133 Elf_Internal_Sym *isymend;
6134 Elf_Internal_Sym *isymbuf;
6135 Elf_External_Versym *ever;
6136 Elf_External_Versym *extversym;
6138 input = loaded->abfd;
6140 /* We check each DSO for a possible hidden versioned definition. */
6141 if (input == abfd
6142 || (input->flags & DYNAMIC) == 0
6143 || elf_dynversym (input) == 0)
6144 continue;
6146 hdr = &elf_tdata (input)->dynsymtab_hdr;
6148 symcount = hdr->sh_size / bed->s->sizeof_sym;
6149 if (elf_bad_symtab (input))
6151 extsymcount = symcount;
6152 extsymoff = 0;
6154 else
6156 extsymcount = symcount - hdr->sh_info;
6157 extsymoff = hdr->sh_info;
6160 if (extsymcount == 0)
6161 continue;
6163 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6164 NULL, NULL, NULL);
6165 if (isymbuf == NULL)
6166 return FALSE;
6168 /* Read in any version definitions. */
6169 versymhdr = &elf_tdata (input)->dynversym_hdr;
6170 extversym = bfd_malloc (versymhdr->sh_size);
6171 if (extversym == NULL)
6172 goto error_ret;
6174 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6175 || (bfd_bread (extversym, versymhdr->sh_size, input)
6176 != versymhdr->sh_size))
6178 free (extversym);
6179 error_ret:
6180 free (isymbuf);
6181 return FALSE;
6184 ever = extversym + extsymoff;
6185 isymend = isymbuf + extsymcount;
6186 for (isym = isymbuf; isym < isymend; isym++, ever++)
6188 const char *name;
6189 Elf_Internal_Versym iver;
6190 unsigned short version_index;
6192 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6193 || isym->st_shndx == SHN_UNDEF)
6194 continue;
6196 name = bfd_elf_string_from_elf_section (input,
6197 hdr->sh_link,
6198 isym->st_name);
6199 if (strcmp (name, h->root.root.string) != 0)
6200 continue;
6202 _bfd_elf_swap_versym_in (input, ever, &iver);
6204 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6206 /* If we have a non-hidden versioned sym, then it should
6207 have provided a definition for the undefined sym. */
6208 abort ();
6211 version_index = iver.vs_vers & VERSYM_VERSION;
6212 if (version_index == 1 || version_index == 2)
6214 /* This is the base or first version. We can use it. */
6215 free (extversym);
6216 free (isymbuf);
6217 return TRUE;
6221 free (extversym);
6222 free (isymbuf);
6225 return FALSE;
6228 /* Add an external symbol to the symbol table. This is called from
6229 the hash table traversal routine. When generating a shared object,
6230 we go through the symbol table twice. The first time we output
6231 anything that might have been forced to local scope in a version
6232 script. The second time we output the symbols that are still
6233 global symbols. */
6235 static bfd_boolean
6236 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6238 struct elf_outext_info *eoinfo = data;
6239 struct elf_final_link_info *finfo = eoinfo->finfo;
6240 bfd_boolean strip;
6241 Elf_Internal_Sym sym;
6242 asection *input_sec;
6243 const struct elf_backend_data *bed;
6245 if (h->root.type == bfd_link_hash_warning)
6247 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6248 if (h->root.type == bfd_link_hash_new)
6249 return TRUE;
6252 /* Decide whether to output this symbol in this pass. */
6253 if (eoinfo->localsyms)
6255 if (!h->forced_local)
6256 return TRUE;
6258 else
6260 if (h->forced_local)
6261 return TRUE;
6264 bed = get_elf_backend_data (finfo->output_bfd);
6266 /* If we have an undefined symbol reference here then it must have
6267 come from a shared library that is being linked in. (Undefined
6268 references in regular files have already been handled). If we
6269 are reporting errors for this situation then do so now. */
6270 if (h->root.type == bfd_link_hash_undefined
6271 && h->ref_dynamic
6272 && !h->ref_regular
6273 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6274 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6276 if (! ((*finfo->info->callbacks->undefined_symbol)
6277 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6278 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6280 eoinfo->failed = TRUE;
6281 return FALSE;
6285 /* We should also warn if a forced local symbol is referenced from
6286 shared libraries. */
6287 if (! finfo->info->relocatable
6288 && (! finfo->info->shared)
6289 && h->forced_local
6290 && h->ref_dynamic
6291 && !h->dynamic_def
6292 && !h->dynamic_weak
6293 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6295 (*_bfd_error_handler)
6296 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6297 finfo->output_bfd, h->root.u.def.section->owner,
6298 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6299 ? "internal"
6300 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6301 ? "hidden" : "local",
6302 h->root.root.string);
6303 eoinfo->failed = TRUE;
6304 return FALSE;
6307 /* We don't want to output symbols that have never been mentioned by
6308 a regular file, or that we have been told to strip. However, if
6309 h->indx is set to -2, the symbol is used by a reloc and we must
6310 output it. */
6311 if (h->indx == -2)
6312 strip = FALSE;
6313 else if ((h->def_dynamic
6314 || h->ref_dynamic
6315 || h->root.type == bfd_link_hash_new)
6316 && !h->def_regular
6317 && !h->ref_regular)
6318 strip = TRUE;
6319 else if (finfo->info->strip == strip_all)
6320 strip = TRUE;
6321 else if (finfo->info->strip == strip_some
6322 && bfd_hash_lookup (finfo->info->keep_hash,
6323 h->root.root.string, FALSE, FALSE) == NULL)
6324 strip = TRUE;
6325 else if (finfo->info->strip_discarded
6326 && (h->root.type == bfd_link_hash_defined
6327 || h->root.type == bfd_link_hash_defweak)
6328 && elf_discarded_section (h->root.u.def.section))
6329 strip = TRUE;
6330 else
6331 strip = FALSE;
6333 /* If we're stripping it, and it's not a dynamic symbol, there's
6334 nothing else to do unless it is a forced local symbol. */
6335 if (strip
6336 && h->dynindx == -1
6337 && !h->forced_local)
6338 return TRUE;
6340 sym.st_value = 0;
6341 sym.st_size = h->size;
6342 sym.st_other = h->other;
6343 if (h->forced_local)
6344 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6345 else if (h->root.type == bfd_link_hash_undefweak
6346 || h->root.type == bfd_link_hash_defweak)
6347 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6348 else
6349 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6351 switch (h->root.type)
6353 default:
6354 case bfd_link_hash_new:
6355 case bfd_link_hash_warning:
6356 abort ();
6357 return FALSE;
6359 case bfd_link_hash_undefined:
6360 case bfd_link_hash_undefweak:
6361 input_sec = bfd_und_section_ptr;
6362 sym.st_shndx = SHN_UNDEF;
6363 break;
6365 case bfd_link_hash_defined:
6366 case bfd_link_hash_defweak:
6368 input_sec = h->root.u.def.section;
6369 if (input_sec->output_section != NULL)
6371 sym.st_shndx =
6372 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6373 input_sec->output_section);
6374 if (sym.st_shndx == SHN_BAD)
6376 (*_bfd_error_handler)
6377 (_("%B: could not find output section %A for input section %A"),
6378 finfo->output_bfd, input_sec->output_section, input_sec);
6379 eoinfo->failed = TRUE;
6380 return FALSE;
6383 /* ELF symbols in relocatable files are section relative,
6384 but in nonrelocatable files they are virtual
6385 addresses. */
6386 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6387 if (! finfo->info->relocatable)
6389 sym.st_value += input_sec->output_section->vma;
6390 if (h->type == STT_TLS)
6392 /* STT_TLS symbols are relative to PT_TLS segment
6393 base. */
6394 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6395 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6399 else
6401 BFD_ASSERT (input_sec->owner == NULL
6402 || (input_sec->owner->flags & DYNAMIC) != 0);
6403 sym.st_shndx = SHN_UNDEF;
6404 input_sec = bfd_und_section_ptr;
6407 break;
6409 case bfd_link_hash_common:
6410 input_sec = h->root.u.c.p->section;
6411 sym.st_shndx = SHN_COMMON;
6412 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6413 break;
6415 case bfd_link_hash_indirect:
6416 /* These symbols are created by symbol versioning. They point
6417 to the decorated version of the name. For example, if the
6418 symbol foo@@GNU_1.2 is the default, which should be used when
6419 foo is used with no version, then we add an indirect symbol
6420 foo which points to foo@@GNU_1.2. We ignore these symbols,
6421 since the indirected symbol is already in the hash table. */
6422 return TRUE;
6425 /* Give the processor backend a chance to tweak the symbol value,
6426 and also to finish up anything that needs to be done for this
6427 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6428 forced local syms when non-shared is due to a historical quirk. */
6429 if ((h->dynindx != -1
6430 || h->forced_local)
6431 && ((finfo->info->shared
6432 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6433 || h->root.type != bfd_link_hash_undefweak))
6434 || !h->forced_local)
6435 && elf_hash_table (finfo->info)->dynamic_sections_created)
6437 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6438 (finfo->output_bfd, finfo->info, h, &sym)))
6440 eoinfo->failed = TRUE;
6441 return FALSE;
6445 /* If we are marking the symbol as undefined, and there are no
6446 non-weak references to this symbol from a regular object, then
6447 mark the symbol as weak undefined; if there are non-weak
6448 references, mark the symbol as strong. We can't do this earlier,
6449 because it might not be marked as undefined until the
6450 finish_dynamic_symbol routine gets through with it. */
6451 if (sym.st_shndx == SHN_UNDEF
6452 && h->ref_regular
6453 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6454 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6456 int bindtype;
6458 if (h->ref_regular_nonweak)
6459 bindtype = STB_GLOBAL;
6460 else
6461 bindtype = STB_WEAK;
6462 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6465 /* If a non-weak symbol with non-default visibility is not defined
6466 locally, it is a fatal error. */
6467 if (! finfo->info->relocatable
6468 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6469 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6470 && h->root.type == bfd_link_hash_undefined
6471 && !h->def_regular)
6473 (*_bfd_error_handler)
6474 (_("%B: %s symbol `%s' isn't defined"),
6475 finfo->output_bfd,
6476 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6477 ? "protected"
6478 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6479 ? "internal" : "hidden",
6480 h->root.root.string);
6481 eoinfo->failed = TRUE;
6482 return FALSE;
6485 /* If this symbol should be put in the .dynsym section, then put it
6486 there now. We already know the symbol index. We also fill in
6487 the entry in the .hash section. */
6488 if (h->dynindx != -1
6489 && elf_hash_table (finfo->info)->dynamic_sections_created)
6491 size_t bucketcount;
6492 size_t bucket;
6493 size_t hash_entry_size;
6494 bfd_byte *bucketpos;
6495 bfd_vma chain;
6496 bfd_byte *esym;
6498 sym.st_name = h->dynstr_index;
6499 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6500 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6502 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6503 bucket = h->u.elf_hash_value % bucketcount;
6504 hash_entry_size
6505 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6506 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6507 + (bucket + 2) * hash_entry_size);
6508 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6509 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6510 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6511 ((bfd_byte *) finfo->hash_sec->contents
6512 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6514 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6516 Elf_Internal_Versym iversym;
6517 Elf_External_Versym *eversym;
6519 if (!h->def_regular)
6521 if (h->verinfo.verdef == NULL)
6522 iversym.vs_vers = 0;
6523 else
6524 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6526 else
6528 if (h->verinfo.vertree == NULL)
6529 iversym.vs_vers = 1;
6530 else
6531 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6532 if (finfo->info->create_default_symver)
6533 iversym.vs_vers++;
6536 if (h->hidden)
6537 iversym.vs_vers |= VERSYM_HIDDEN;
6539 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6540 eversym += h->dynindx;
6541 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6545 /* If we're stripping it, then it was just a dynamic symbol, and
6546 there's nothing else to do. */
6547 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6548 return TRUE;
6550 h->indx = bfd_get_symcount (finfo->output_bfd);
6552 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6554 eoinfo->failed = TRUE;
6555 return FALSE;
6558 return TRUE;
6561 /* Return TRUE if special handling is done for relocs in SEC against
6562 symbols defined in discarded sections. */
6564 static bfd_boolean
6565 elf_section_ignore_discarded_relocs (asection *sec)
6567 const struct elf_backend_data *bed;
6569 switch (sec->sec_info_type)
6571 case ELF_INFO_TYPE_STABS:
6572 case ELF_INFO_TYPE_EH_FRAME:
6573 return TRUE;
6574 default:
6575 break;
6578 bed = get_elf_backend_data (sec->owner);
6579 if (bed->elf_backend_ignore_discarded_relocs != NULL
6580 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6581 return TRUE;
6583 return FALSE;
6586 enum action_discarded
6588 COMPLAIN = 1,
6589 PRETEND = 2
6592 /* Return a mask saying how ld should treat relocations in SEC against
6593 symbols defined in discarded sections. If this function returns
6594 COMPLAIN set, ld will issue a warning message. If this function
6595 returns PRETEND set, and the discarded section was link-once and the
6596 same size as the kept link-once section, ld will pretend that the
6597 symbol was actually defined in the kept section. Otherwise ld will
6598 zero the reloc (at least that is the intent, but some cooperation by
6599 the target dependent code is needed, particularly for REL targets). */
6601 static unsigned int
6602 elf_action_discarded (asection *sec)
6604 if (sec->flags & SEC_DEBUGGING)
6605 return PRETEND;
6607 if (strcmp (".eh_frame", sec->name) == 0)
6608 return 0;
6610 if (strcmp (".gcc_except_table", sec->name) == 0)
6611 return 0;
6613 if (strcmp (".PARISC.unwind", sec->name) == 0)
6614 return 0;
6616 if (strcmp (".fixup", sec->name) == 0)
6617 return 0;
6619 return COMPLAIN | PRETEND;
6622 /* Find a match between a section and a member of a section group. */
6624 static asection *
6625 match_group_member (asection *sec, asection *group)
6627 asection *first = elf_next_in_group (group);
6628 asection *s = first;
6630 while (s != NULL)
6632 if (bfd_elf_match_symbols_in_sections (s, sec))
6633 return s;
6635 if (s == first)
6636 break;
6639 return NULL;
6642 /* Link an input file into the linker output file. This function
6643 handles all the sections and relocations of the input file at once.
6644 This is so that we only have to read the local symbols once, and
6645 don't have to keep them in memory. */
6647 static bfd_boolean
6648 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6650 bfd_boolean (*relocate_section)
6651 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6652 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6653 bfd *output_bfd;
6654 Elf_Internal_Shdr *symtab_hdr;
6655 size_t locsymcount;
6656 size_t extsymoff;
6657 Elf_Internal_Sym *isymbuf;
6658 Elf_Internal_Sym *isym;
6659 Elf_Internal_Sym *isymend;
6660 long *pindex;
6661 asection **ppsection;
6662 asection *o;
6663 const struct elf_backend_data *bed;
6664 bfd_boolean emit_relocs;
6665 struct elf_link_hash_entry **sym_hashes;
6667 output_bfd = finfo->output_bfd;
6668 bed = get_elf_backend_data (output_bfd);
6669 relocate_section = bed->elf_backend_relocate_section;
6671 /* If this is a dynamic object, we don't want to do anything here:
6672 we don't want the local symbols, and we don't want the section
6673 contents. */
6674 if ((input_bfd->flags & DYNAMIC) != 0)
6675 return TRUE;
6677 emit_relocs = (finfo->info->relocatable
6678 || finfo->info->emitrelocations
6679 || bed->elf_backend_emit_relocs);
6681 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6682 if (elf_bad_symtab (input_bfd))
6684 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6685 extsymoff = 0;
6687 else
6689 locsymcount = symtab_hdr->sh_info;
6690 extsymoff = symtab_hdr->sh_info;
6693 /* Read the local symbols. */
6694 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6695 if (isymbuf == NULL && locsymcount != 0)
6697 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6698 finfo->internal_syms,
6699 finfo->external_syms,
6700 finfo->locsym_shndx);
6701 if (isymbuf == NULL)
6702 return FALSE;
6705 /* Find local symbol sections and adjust values of symbols in
6706 SEC_MERGE sections. Write out those local symbols we know are
6707 going into the output file. */
6708 isymend = isymbuf + locsymcount;
6709 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6710 isym < isymend;
6711 isym++, pindex++, ppsection++)
6713 asection *isec;
6714 const char *name;
6715 Elf_Internal_Sym osym;
6717 *pindex = -1;
6719 if (elf_bad_symtab (input_bfd))
6721 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6723 *ppsection = NULL;
6724 continue;
6728 if (isym->st_shndx == SHN_UNDEF)
6729 isec = bfd_und_section_ptr;
6730 else if (isym->st_shndx < SHN_LORESERVE
6731 || isym->st_shndx > SHN_HIRESERVE)
6733 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6734 if (isec
6735 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6736 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6737 isym->st_value =
6738 _bfd_merged_section_offset (output_bfd, &isec,
6739 elf_section_data (isec)->sec_info,
6740 isym->st_value);
6742 else if (isym->st_shndx == SHN_ABS)
6743 isec = bfd_abs_section_ptr;
6744 else if (isym->st_shndx == SHN_COMMON)
6745 isec = bfd_com_section_ptr;
6746 else
6748 /* Who knows? */
6749 isec = NULL;
6752 *ppsection = isec;
6754 /* Don't output the first, undefined, symbol. */
6755 if (ppsection == finfo->sections)
6756 continue;
6758 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6760 /* We never output section symbols. Instead, we use the
6761 section symbol of the corresponding section in the output
6762 file. */
6763 continue;
6766 /* If we are stripping all symbols, we don't want to output this
6767 one. */
6768 if (finfo->info->strip == strip_all)
6769 continue;
6771 /* If we are discarding all local symbols, we don't want to
6772 output this one. If we are generating a relocatable output
6773 file, then some of the local symbols may be required by
6774 relocs; we output them below as we discover that they are
6775 needed. */
6776 if (finfo->info->discard == discard_all)
6777 continue;
6779 /* If this symbol is defined in a section which we are
6780 discarding, we don't need to keep it, but note that
6781 linker_mark is only reliable for sections that have contents.
6782 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
6783 as well as linker_mark. */
6784 if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6785 && (isec == NULL
6786 || (! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
6787 || (! finfo->info->relocatable
6788 && (isec->flags & SEC_EXCLUDE) != 0)))
6789 continue;
6791 /* Get the name of the symbol. */
6792 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6793 isym->st_name);
6794 if (name == NULL)
6795 return FALSE;
6797 /* See if we are discarding symbols with this name. */
6798 if ((finfo->info->strip == strip_some
6799 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6800 == NULL))
6801 || (((finfo->info->discard == discard_sec_merge
6802 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6803 || finfo->info->discard == discard_l)
6804 && bfd_is_local_label_name (input_bfd, name)))
6805 continue;
6807 /* If we get here, we are going to output this symbol. */
6809 osym = *isym;
6811 /* Adjust the section index for the output file. */
6812 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6813 isec->output_section);
6814 if (osym.st_shndx == SHN_BAD)
6815 return FALSE;
6817 *pindex = bfd_get_symcount (output_bfd);
6819 /* ELF symbols in relocatable files are section relative, but
6820 in executable files they are virtual addresses. Note that
6821 this code assumes that all ELF sections have an associated
6822 BFD section with a reasonable value for output_offset; below
6823 we assume that they also have a reasonable value for
6824 output_section. Any special sections must be set up to meet
6825 these requirements. */
6826 osym.st_value += isec->output_offset;
6827 if (! finfo->info->relocatable)
6829 osym.st_value += isec->output_section->vma;
6830 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
6832 /* STT_TLS symbols are relative to PT_TLS segment base. */
6833 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6834 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6838 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
6839 return FALSE;
6842 /* Relocate the contents of each section. */
6843 sym_hashes = elf_sym_hashes (input_bfd);
6844 for (o = input_bfd->sections; o != NULL; o = o->next)
6846 bfd_byte *contents;
6848 if (! o->linker_mark)
6850 /* This section was omitted from the link. */
6851 continue;
6854 if ((o->flags & SEC_HAS_CONTENTS) == 0
6855 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
6856 continue;
6858 if ((o->flags & SEC_LINKER_CREATED) != 0)
6860 /* Section was created by _bfd_elf_link_create_dynamic_sections
6861 or somesuch. */
6862 continue;
6865 /* Get the contents of the section. They have been cached by a
6866 relaxation routine. Note that o is a section in an input
6867 file, so the contents field will not have been set by any of
6868 the routines which work on output files. */
6869 if (elf_section_data (o)->this_hdr.contents != NULL)
6870 contents = elf_section_data (o)->this_hdr.contents;
6871 else
6873 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
6875 contents = finfo->contents;
6876 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
6877 return FALSE;
6880 if ((o->flags & SEC_RELOC) != 0)
6882 Elf_Internal_Rela *internal_relocs;
6883 bfd_vma r_type_mask;
6884 int r_sym_shift;
6886 /* Get the swapped relocs. */
6887 internal_relocs
6888 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
6889 finfo->internal_relocs, FALSE);
6890 if (internal_relocs == NULL
6891 && o->reloc_count > 0)
6892 return FALSE;
6894 if (bed->s->arch_size == 32)
6896 r_type_mask = 0xff;
6897 r_sym_shift = 8;
6899 else
6901 r_type_mask = 0xffffffff;
6902 r_sym_shift = 32;
6905 /* Run through the relocs looking for any against symbols
6906 from discarded sections and section symbols from
6907 removed link-once sections. Complain about relocs
6908 against discarded sections. Zero relocs against removed
6909 link-once sections. Preserve debug information as much
6910 as we can. */
6911 if (!elf_section_ignore_discarded_relocs (o))
6913 Elf_Internal_Rela *rel, *relend;
6914 unsigned int action = elf_action_discarded (o);
6916 rel = internal_relocs;
6917 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
6918 for ( ; rel < relend; rel++)
6920 unsigned long r_symndx = rel->r_info >> r_sym_shift;
6921 asection **ps, *sec;
6922 struct elf_link_hash_entry *h = NULL;
6923 const char *sym_name;
6925 if (r_symndx == STN_UNDEF)
6926 continue;
6928 if (r_symndx >= locsymcount
6929 || (elf_bad_symtab (input_bfd)
6930 && finfo->sections[r_symndx] == NULL))
6932 h = sym_hashes[r_symndx - extsymoff];
6933 while (h->root.type == bfd_link_hash_indirect
6934 || h->root.type == bfd_link_hash_warning)
6935 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6937 if (h->root.type != bfd_link_hash_defined
6938 && h->root.type != bfd_link_hash_defweak)
6939 continue;
6941 ps = &h->root.u.def.section;
6942 sym_name = h->root.root.string;
6944 else
6946 Elf_Internal_Sym *sym = isymbuf + r_symndx;
6947 ps = &finfo->sections[r_symndx];
6948 sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym);
6951 /* Complain if the definition comes from a
6952 discarded section. */
6953 if ((sec = *ps) != NULL && elf_discarded_section (sec))
6955 asection *kept;
6957 BFD_ASSERT (r_symndx != 0);
6958 if (action & COMPLAIN)
6960 (*_bfd_error_handler)
6961 (_("`%s' referenced in section `%A' of %B: "
6962 "defined in discarded section `%A' of %B\n"),
6963 o, input_bfd, sec, sec->owner, sym_name);
6966 /* Try to do the best we can to support buggy old
6967 versions of gcc. If we've warned, or this is
6968 debugging info, pretend that the symbol is
6969 really defined in the kept linkonce section.
6970 FIXME: This is quite broken. Modifying the
6971 symbol here means we will be changing all later
6972 uses of the symbol, not just in this section.
6973 The only thing that makes this half reasonable
6974 is that we warn in non-debug sections, and
6975 debug sections tend to come after other
6976 sections. */
6977 kept = sec->kept_section;
6978 if (kept != NULL && (action & PRETEND))
6980 if (elf_sec_group (sec) != NULL)
6981 kept = match_group_member (sec, kept);
6982 if (kept != NULL
6983 && sec->size == kept->size)
6985 *ps = kept;
6986 continue;
6990 /* Remove the symbol reference from the reloc, but
6991 don't kill the reloc completely. This is so that
6992 a zero value will be written into the section,
6993 which may have non-zero contents put there by the
6994 assembler. Zero in things like an eh_frame fde
6995 pc_begin allows stack unwinders to recognize the
6996 fde as bogus. */
6997 rel->r_info &= r_type_mask;
6998 rel->r_addend = 0;
7003 /* Relocate the section by invoking a back end routine.
7005 The back end routine is responsible for adjusting the
7006 section contents as necessary, and (if using Rela relocs
7007 and generating a relocatable output file) adjusting the
7008 reloc addend as necessary.
7010 The back end routine does not have to worry about setting
7011 the reloc address or the reloc symbol index.
7013 The back end routine is given a pointer to the swapped in
7014 internal symbols, and can access the hash table entries
7015 for the external symbols via elf_sym_hashes (input_bfd).
7017 When generating relocatable output, the back end routine
7018 must handle STB_LOCAL/STT_SECTION symbols specially. The
7019 output symbol is going to be a section symbol
7020 corresponding to the output section, which will require
7021 the addend to be adjusted. */
7023 if (! (*relocate_section) (output_bfd, finfo->info,
7024 input_bfd, o, contents,
7025 internal_relocs,
7026 isymbuf,
7027 finfo->sections))
7028 return FALSE;
7030 if (emit_relocs)
7032 Elf_Internal_Rela *irela;
7033 Elf_Internal_Rela *irelaend;
7034 bfd_vma last_offset;
7035 struct elf_link_hash_entry **rel_hash;
7036 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7037 unsigned int next_erel;
7038 bfd_boolean (*reloc_emitter)
7039 (bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *);
7040 bfd_boolean rela_normal;
7042 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7043 rela_normal = (bed->rela_normal
7044 && (input_rel_hdr->sh_entsize
7045 == bed->s->sizeof_rela));
7047 /* Adjust the reloc addresses and symbol indices. */
7049 irela = internal_relocs;
7050 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7051 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7052 + elf_section_data (o->output_section)->rel_count
7053 + elf_section_data (o->output_section)->rel_count2);
7054 last_offset = o->output_offset;
7055 if (!finfo->info->relocatable)
7056 last_offset += o->output_section->vma;
7057 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7059 unsigned long r_symndx;
7060 asection *sec;
7061 Elf_Internal_Sym sym;
7063 if (next_erel == bed->s->int_rels_per_ext_rel)
7065 rel_hash++;
7066 next_erel = 0;
7069 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7070 finfo->info, o,
7071 irela->r_offset);
7072 if (irela->r_offset >= (bfd_vma) -2)
7074 /* This is a reloc for a deleted entry or somesuch.
7075 Turn it into an R_*_NONE reloc, at the same
7076 offset as the last reloc. elf_eh_frame.c and
7077 elf_bfd_discard_info rely on reloc offsets
7078 being ordered. */
7079 irela->r_offset = last_offset;
7080 irela->r_info = 0;
7081 irela->r_addend = 0;
7082 continue;
7085 irela->r_offset += o->output_offset;
7087 /* Relocs in an executable have to be virtual addresses. */
7088 if (!finfo->info->relocatable)
7089 irela->r_offset += o->output_section->vma;
7091 last_offset = irela->r_offset;
7093 r_symndx = irela->r_info >> r_sym_shift;
7094 if (r_symndx == STN_UNDEF)
7095 continue;
7097 if (r_symndx >= locsymcount
7098 || (elf_bad_symtab (input_bfd)
7099 && finfo->sections[r_symndx] == NULL))
7101 struct elf_link_hash_entry *rh;
7102 unsigned long indx;
7104 /* This is a reloc against a global symbol. We
7105 have not yet output all the local symbols, so
7106 we do not know the symbol index of any global
7107 symbol. We set the rel_hash entry for this
7108 reloc to point to the global hash table entry
7109 for this symbol. The symbol index is then
7110 set at the end of bfd_elf_final_link. */
7111 indx = r_symndx - extsymoff;
7112 rh = elf_sym_hashes (input_bfd)[indx];
7113 while (rh->root.type == bfd_link_hash_indirect
7114 || rh->root.type == bfd_link_hash_warning)
7115 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7117 /* Setting the index to -2 tells
7118 elf_link_output_extsym that this symbol is
7119 used by a reloc. */
7120 BFD_ASSERT (rh->indx < 0);
7121 rh->indx = -2;
7123 *rel_hash = rh;
7125 continue;
7128 /* This is a reloc against a local symbol. */
7130 *rel_hash = NULL;
7131 sym = isymbuf[r_symndx];
7132 sec = finfo->sections[r_symndx];
7133 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7135 /* I suppose the backend ought to fill in the
7136 section of any STT_SECTION symbol against a
7137 processor specific section. */
7138 r_symndx = 0;
7139 if (bfd_is_abs_section (sec))
7141 else if (sec == NULL || sec->owner == NULL)
7143 bfd_set_error (bfd_error_bad_value);
7144 return FALSE;
7146 else
7148 asection *osec = sec->output_section;
7150 /* If we have discarded a section, the output
7151 section will be the absolute section. In
7152 case of discarded link-once and discarded
7153 SEC_MERGE sections, use the kept section. */
7154 if (bfd_is_abs_section (osec)
7155 && sec->kept_section != NULL
7156 && sec->kept_section->output_section != NULL)
7158 osec = sec->kept_section->output_section;
7159 irela->r_addend -= osec->vma;
7162 if (!bfd_is_abs_section (osec))
7164 r_symndx = osec->target_index;
7165 BFD_ASSERT (r_symndx != 0);
7169 /* Adjust the addend according to where the
7170 section winds up in the output section. */
7171 if (rela_normal)
7172 irela->r_addend += sec->output_offset;
7174 else
7176 if (finfo->indices[r_symndx] == -1)
7178 unsigned long shlink;
7179 const char *name;
7180 asection *osec;
7182 if (finfo->info->strip == strip_all)
7184 /* You can't do ld -r -s. */
7185 bfd_set_error (bfd_error_invalid_operation);
7186 return FALSE;
7189 /* This symbol was skipped earlier, but
7190 since it is needed by a reloc, we
7191 must output it now. */
7192 shlink = symtab_hdr->sh_link;
7193 name = (bfd_elf_string_from_elf_section
7194 (input_bfd, shlink, sym.st_name));
7195 if (name == NULL)
7196 return FALSE;
7198 osec = sec->output_section;
7199 sym.st_shndx =
7200 _bfd_elf_section_from_bfd_section (output_bfd,
7201 osec);
7202 if (sym.st_shndx == SHN_BAD)
7203 return FALSE;
7205 sym.st_value += sec->output_offset;
7206 if (! finfo->info->relocatable)
7208 sym.st_value += osec->vma;
7209 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7211 /* STT_TLS symbols are relative to PT_TLS
7212 segment base. */
7213 BFD_ASSERT (elf_hash_table (finfo->info)
7214 ->tls_sec != NULL);
7215 sym.st_value -= (elf_hash_table (finfo->info)
7216 ->tls_sec->vma);
7220 finfo->indices[r_symndx]
7221 = bfd_get_symcount (output_bfd);
7223 if (! elf_link_output_sym (finfo, name, &sym, sec,
7224 NULL))
7225 return FALSE;
7228 r_symndx = finfo->indices[r_symndx];
7231 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7232 | (irela->r_info & r_type_mask));
7235 /* Swap out the relocs. */
7236 if (bed->elf_backend_emit_relocs
7237 && !(finfo->info->relocatable
7238 || finfo->info->emitrelocations))
7239 reloc_emitter = bed->elf_backend_emit_relocs;
7240 else
7241 reloc_emitter = _bfd_elf_link_output_relocs;
7243 if (input_rel_hdr->sh_size != 0
7244 && ! (*reloc_emitter) (output_bfd, o, input_rel_hdr,
7245 internal_relocs))
7246 return FALSE;
7248 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7249 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7251 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7252 * bed->s->int_rels_per_ext_rel);
7253 if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2,
7254 internal_relocs))
7255 return FALSE;
7260 /* Write out the modified section contents. */
7261 if (bed->elf_backend_write_section
7262 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7264 /* Section written out. */
7266 else switch (o->sec_info_type)
7268 case ELF_INFO_TYPE_STABS:
7269 if (! (_bfd_write_section_stabs
7270 (output_bfd,
7271 &elf_hash_table (finfo->info)->stab_info,
7272 o, &elf_section_data (o)->sec_info, contents)))
7273 return FALSE;
7274 break;
7275 case ELF_INFO_TYPE_MERGE:
7276 if (! _bfd_write_merged_section (output_bfd, o,
7277 elf_section_data (o)->sec_info))
7278 return FALSE;
7279 break;
7280 case ELF_INFO_TYPE_EH_FRAME:
7282 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7283 o, contents))
7284 return FALSE;
7286 break;
7287 default:
7289 if (! (o->flags & SEC_EXCLUDE)
7290 && ! bfd_set_section_contents (output_bfd, o->output_section,
7291 contents,
7292 (file_ptr) o->output_offset,
7293 o->size))
7294 return FALSE;
7296 break;
7300 return TRUE;
7303 /* Generate a reloc when linking an ELF file. This is a reloc
7304 requested by the linker, and does come from any input file. This
7305 is used to build constructor and destructor tables when linking
7306 with -Ur. */
7308 static bfd_boolean
7309 elf_reloc_link_order (bfd *output_bfd,
7310 struct bfd_link_info *info,
7311 asection *output_section,
7312 struct bfd_link_order *link_order)
7314 reloc_howto_type *howto;
7315 long indx;
7316 bfd_vma offset;
7317 bfd_vma addend;
7318 struct elf_link_hash_entry **rel_hash_ptr;
7319 Elf_Internal_Shdr *rel_hdr;
7320 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7321 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7322 bfd_byte *erel;
7323 unsigned int i;
7325 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7326 if (howto == NULL)
7328 bfd_set_error (bfd_error_bad_value);
7329 return FALSE;
7332 addend = link_order->u.reloc.p->addend;
7334 /* Figure out the symbol index. */
7335 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7336 + elf_section_data (output_section)->rel_count
7337 + elf_section_data (output_section)->rel_count2);
7338 if (link_order->type == bfd_section_reloc_link_order)
7340 indx = link_order->u.reloc.p->u.section->target_index;
7341 BFD_ASSERT (indx != 0);
7342 *rel_hash_ptr = NULL;
7344 else
7346 struct elf_link_hash_entry *h;
7348 /* Treat a reloc against a defined symbol as though it were
7349 actually against the section. */
7350 h = ((struct elf_link_hash_entry *)
7351 bfd_wrapped_link_hash_lookup (output_bfd, info,
7352 link_order->u.reloc.p->u.name,
7353 FALSE, FALSE, TRUE));
7354 if (h != NULL
7355 && (h->root.type == bfd_link_hash_defined
7356 || h->root.type == bfd_link_hash_defweak))
7358 asection *section;
7360 section = h->root.u.def.section;
7361 indx = section->output_section->target_index;
7362 *rel_hash_ptr = NULL;
7363 /* It seems that we ought to add the symbol value to the
7364 addend here, but in practice it has already been added
7365 because it was passed to constructor_callback. */
7366 addend += section->output_section->vma + section->output_offset;
7368 else if (h != NULL)
7370 /* Setting the index to -2 tells elf_link_output_extsym that
7371 this symbol is used by a reloc. */
7372 h->indx = -2;
7373 *rel_hash_ptr = h;
7374 indx = 0;
7376 else
7378 if (! ((*info->callbacks->unattached_reloc)
7379 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7380 return FALSE;
7381 indx = 0;
7385 /* If this is an inplace reloc, we must write the addend into the
7386 object file. */
7387 if (howto->partial_inplace && addend != 0)
7389 bfd_size_type size;
7390 bfd_reloc_status_type rstat;
7391 bfd_byte *buf;
7392 bfd_boolean ok;
7393 const char *sym_name;
7395 size = bfd_get_reloc_size (howto);
7396 buf = bfd_zmalloc (size);
7397 if (buf == NULL)
7398 return FALSE;
7399 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7400 switch (rstat)
7402 case bfd_reloc_ok:
7403 break;
7405 default:
7406 case bfd_reloc_outofrange:
7407 abort ();
7409 case bfd_reloc_overflow:
7410 if (link_order->type == bfd_section_reloc_link_order)
7411 sym_name = bfd_section_name (output_bfd,
7412 link_order->u.reloc.p->u.section);
7413 else
7414 sym_name = link_order->u.reloc.p->u.name;
7415 if (! ((*info->callbacks->reloc_overflow)
7416 (info, NULL, sym_name, howto->name, addend, NULL,
7417 NULL, (bfd_vma) 0)))
7419 free (buf);
7420 return FALSE;
7422 break;
7424 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7425 link_order->offset, size);
7426 free (buf);
7427 if (! ok)
7428 return FALSE;
7431 /* The address of a reloc is relative to the section in a
7432 relocatable file, and is a virtual address in an executable
7433 file. */
7434 offset = link_order->offset;
7435 if (! info->relocatable)
7436 offset += output_section->vma;
7438 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7440 irel[i].r_offset = offset;
7441 irel[i].r_info = 0;
7442 irel[i].r_addend = 0;
7444 if (bed->s->arch_size == 32)
7445 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7446 else
7447 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7449 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7450 erel = rel_hdr->contents;
7451 if (rel_hdr->sh_type == SHT_REL)
7453 erel += (elf_section_data (output_section)->rel_count
7454 * bed->s->sizeof_rel);
7455 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7457 else
7459 irel[0].r_addend = addend;
7460 erel += (elf_section_data (output_section)->rel_count
7461 * bed->s->sizeof_rela);
7462 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7465 ++elf_section_data (output_section)->rel_count;
7467 return TRUE;
7471 /* Get the output vma of the section pointed to by the sh_link field. */
7473 static bfd_vma
7474 elf_get_linked_section_vma (struct bfd_link_order *p)
7476 Elf_Internal_Shdr **elf_shdrp;
7477 asection *s;
7478 int elfsec;
7480 s = p->u.indirect.section;
7481 elf_shdrp = elf_elfsections (s->owner);
7482 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7483 elfsec = elf_shdrp[elfsec]->sh_link;
7484 /* PR 290:
7485 The Intel C compiler generates SHT_IA_64_UNWIND with
7486 SHF_LINK_ORDER. But it doesn't set theh sh_link or
7487 sh_info fields. Hence we could get the situation
7488 where elfsec is 0. */
7489 if (elfsec == 0)
7491 const struct elf_backend_data *bed
7492 = get_elf_backend_data (s->owner);
7493 if (bed->link_order_error_handler)
7494 bed->link_order_error_handler
7495 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
7496 return 0;
7498 else
7500 s = elf_shdrp[elfsec]->bfd_section;
7501 return s->output_section->vma + s->output_offset;
7506 /* Compare two sections based on the locations of the sections they are
7507 linked to. Used by elf_fixup_link_order. */
7509 static int
7510 compare_link_order (const void * a, const void * b)
7512 bfd_vma apos;
7513 bfd_vma bpos;
7515 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7516 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7517 if (apos < bpos)
7518 return -1;
7519 return apos > bpos;
7523 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7524 order as their linked sections. Returns false if this could not be done
7525 because an output section includes both ordered and unordered
7526 sections. Ideally we'd do this in the linker proper. */
7528 static bfd_boolean
7529 elf_fixup_link_order (bfd *abfd, asection *o)
7531 int seen_linkorder;
7532 int seen_other;
7533 int n;
7534 struct bfd_link_order *p;
7535 bfd *sub;
7536 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7537 int elfsec;
7538 struct bfd_link_order **sections;
7539 asection *s;
7540 bfd_vma offset;
7542 seen_other = 0;
7543 seen_linkorder = 0;
7544 for (p = o->link_order_head; p != NULL; p = p->next)
7546 if (p->type == bfd_indirect_link_order
7547 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7548 == bfd_target_elf_flavour)
7549 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7551 s = p->u.indirect.section;
7552 elfsec = _bfd_elf_section_from_bfd_section (sub, s);
7553 if (elfsec != -1
7554 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7555 seen_linkorder++;
7556 else
7557 seen_other++;
7559 else
7560 seen_other++;
7563 if (!seen_linkorder)
7564 return TRUE;
7566 if (seen_other && seen_linkorder)
7568 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
7570 bfd_set_error (bfd_error_bad_value);
7571 return FALSE;
7574 sections = (struct bfd_link_order **)
7575 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7576 seen_linkorder = 0;
7578 for (p = o->link_order_head; p != NULL; p = p->next)
7580 sections[seen_linkorder++] = p;
7582 /* Sort the input sections in the order of their linked section. */
7583 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7584 compare_link_order);
7586 /* Change the offsets of the sections. */
7587 offset = 0;
7588 for (n = 0; n < seen_linkorder; n++)
7590 s = sections[n]->u.indirect.section;
7591 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7592 s->output_offset = offset;
7593 sections[n]->offset = offset;
7594 offset += sections[n]->size;
7597 return TRUE;
7601 /* Do the final step of an ELF link. */
7603 bfd_boolean
7604 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7606 bfd_boolean dynamic;
7607 bfd_boolean emit_relocs;
7608 bfd *dynobj;
7609 struct elf_final_link_info finfo;
7610 register asection *o;
7611 register struct bfd_link_order *p;
7612 register bfd *sub;
7613 bfd_size_type max_contents_size;
7614 bfd_size_type max_external_reloc_size;
7615 bfd_size_type max_internal_reloc_count;
7616 bfd_size_type max_sym_count;
7617 bfd_size_type max_sym_shndx_count;
7618 file_ptr off;
7619 Elf_Internal_Sym elfsym;
7620 unsigned int i;
7621 Elf_Internal_Shdr *symtab_hdr;
7622 Elf_Internal_Shdr *symtab_shndx_hdr;
7623 Elf_Internal_Shdr *symstrtab_hdr;
7624 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7625 struct elf_outext_info eoinfo;
7626 bfd_boolean merged;
7627 size_t relativecount = 0;
7628 asection *reldyn = 0;
7629 bfd_size_type amt;
7631 if (! is_elf_hash_table (info->hash))
7632 return FALSE;
7634 if (info->shared)
7635 abfd->flags |= DYNAMIC;
7637 dynamic = elf_hash_table (info)->dynamic_sections_created;
7638 dynobj = elf_hash_table (info)->dynobj;
7640 emit_relocs = (info->relocatable
7641 || info->emitrelocations
7642 || bed->elf_backend_emit_relocs);
7644 finfo.info = info;
7645 finfo.output_bfd = abfd;
7646 finfo.symstrtab = _bfd_elf_stringtab_init ();
7647 if (finfo.symstrtab == NULL)
7648 return FALSE;
7650 if (! dynamic)
7652 finfo.dynsym_sec = NULL;
7653 finfo.hash_sec = NULL;
7654 finfo.symver_sec = NULL;
7656 else
7658 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7659 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7660 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7661 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7662 /* Note that it is OK if symver_sec is NULL. */
7665 finfo.contents = NULL;
7666 finfo.external_relocs = NULL;
7667 finfo.internal_relocs = NULL;
7668 finfo.external_syms = NULL;
7669 finfo.locsym_shndx = NULL;
7670 finfo.internal_syms = NULL;
7671 finfo.indices = NULL;
7672 finfo.sections = NULL;
7673 finfo.symbuf = NULL;
7674 finfo.symshndxbuf = NULL;
7675 finfo.symbuf_count = 0;
7676 finfo.shndxbuf_size = 0;
7678 /* Count up the number of relocations we will output for each output
7679 section, so that we know the sizes of the reloc sections. We
7680 also figure out some maximum sizes. */
7681 max_contents_size = 0;
7682 max_external_reloc_size = 0;
7683 max_internal_reloc_count = 0;
7684 max_sym_count = 0;
7685 max_sym_shndx_count = 0;
7686 merged = FALSE;
7687 for (o = abfd->sections; o != NULL; o = o->next)
7689 struct bfd_elf_section_data *esdo = elf_section_data (o);
7690 o->reloc_count = 0;
7692 for (p = o->link_order_head; p != NULL; p = p->next)
7694 unsigned int reloc_count = 0;
7695 struct bfd_elf_section_data *esdi = NULL;
7696 unsigned int *rel_count1;
7698 if (p->type == bfd_section_reloc_link_order
7699 || p->type == bfd_symbol_reloc_link_order)
7700 reloc_count = 1;
7701 else if (p->type == bfd_indirect_link_order)
7703 asection *sec;
7705 sec = p->u.indirect.section;
7706 esdi = elf_section_data (sec);
7708 /* Mark all sections which are to be included in the
7709 link. This will normally be every section. We need
7710 to do this so that we can identify any sections which
7711 the linker has decided to not include. */
7712 sec->linker_mark = TRUE;
7714 if (sec->flags & SEC_MERGE)
7715 merged = TRUE;
7717 if (info->relocatable || info->emitrelocations)
7718 reloc_count = sec->reloc_count;
7719 else if (bed->elf_backend_count_relocs)
7721 Elf_Internal_Rela * relocs;
7723 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7724 info->keep_memory);
7726 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7728 if (elf_section_data (o)->relocs != relocs)
7729 free (relocs);
7732 if (sec->rawsize > max_contents_size)
7733 max_contents_size = sec->rawsize;
7734 if (sec->size > max_contents_size)
7735 max_contents_size = sec->size;
7737 /* We are interested in just local symbols, not all
7738 symbols. */
7739 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7740 && (sec->owner->flags & DYNAMIC) == 0)
7742 size_t sym_count;
7744 if (elf_bad_symtab (sec->owner))
7745 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7746 / bed->s->sizeof_sym);
7747 else
7748 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7750 if (sym_count > max_sym_count)
7751 max_sym_count = sym_count;
7753 if (sym_count > max_sym_shndx_count
7754 && elf_symtab_shndx (sec->owner) != 0)
7755 max_sym_shndx_count = sym_count;
7757 if ((sec->flags & SEC_RELOC) != 0)
7759 size_t ext_size;
7761 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7762 if (ext_size > max_external_reloc_size)
7763 max_external_reloc_size = ext_size;
7764 if (sec->reloc_count > max_internal_reloc_count)
7765 max_internal_reloc_count = sec->reloc_count;
7770 if (reloc_count == 0)
7771 continue;
7773 o->reloc_count += reloc_count;
7775 /* MIPS may have a mix of REL and RELA relocs on sections.
7776 To support this curious ABI we keep reloc counts in
7777 elf_section_data too. We must be careful to add the
7778 relocations from the input section to the right output
7779 count. FIXME: Get rid of one count. We have
7780 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7781 rel_count1 = &esdo->rel_count;
7782 if (esdi != NULL)
7784 bfd_boolean same_size;
7785 bfd_size_type entsize1;
7787 entsize1 = esdi->rel_hdr.sh_entsize;
7788 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7789 || entsize1 == bed->s->sizeof_rela);
7790 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7792 if (!same_size)
7793 rel_count1 = &esdo->rel_count2;
7795 if (esdi->rel_hdr2 != NULL)
7797 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7798 unsigned int alt_count;
7799 unsigned int *rel_count2;
7801 BFD_ASSERT (entsize2 != entsize1
7802 && (entsize2 == bed->s->sizeof_rel
7803 || entsize2 == bed->s->sizeof_rela));
7805 rel_count2 = &esdo->rel_count2;
7806 if (!same_size)
7807 rel_count2 = &esdo->rel_count;
7809 /* The following is probably too simplistic if the
7810 backend counts output relocs unusually. */
7811 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7812 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
7813 *rel_count2 += alt_count;
7814 reloc_count -= alt_count;
7817 *rel_count1 += reloc_count;
7820 if (o->reloc_count > 0)
7821 o->flags |= SEC_RELOC;
7822 else
7824 /* Explicitly clear the SEC_RELOC flag. The linker tends to
7825 set it (this is probably a bug) and if it is set
7826 assign_section_numbers will create a reloc section. */
7827 o->flags &=~ SEC_RELOC;
7830 /* If the SEC_ALLOC flag is not set, force the section VMA to
7831 zero. This is done in elf_fake_sections as well, but forcing
7832 the VMA to 0 here will ensure that relocs against these
7833 sections are handled correctly. */
7834 if ((o->flags & SEC_ALLOC) == 0
7835 && ! o->user_set_vma)
7836 o->vma = 0;
7839 if (! info->relocatable && merged)
7840 elf_link_hash_traverse (elf_hash_table (info),
7841 _bfd_elf_link_sec_merge_syms, abfd);
7843 /* Figure out the file positions for everything but the symbol table
7844 and the relocs. We set symcount to force assign_section_numbers
7845 to create a symbol table. */
7846 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
7847 BFD_ASSERT (! abfd->output_has_begun);
7848 if (! _bfd_elf_compute_section_file_positions (abfd, info))
7849 goto error_return;
7851 /* Set sizes, and assign file positions for reloc sections. */
7852 for (o = abfd->sections; o != NULL; o = o->next)
7854 if ((o->flags & SEC_RELOC) != 0)
7856 if (!(_bfd_elf_link_size_reloc_section
7857 (abfd, &elf_section_data (o)->rel_hdr, o)))
7858 goto error_return;
7860 if (elf_section_data (o)->rel_hdr2
7861 && !(_bfd_elf_link_size_reloc_section
7862 (abfd, elf_section_data (o)->rel_hdr2, o)))
7863 goto error_return;
7866 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
7867 to count upwards while actually outputting the relocations. */
7868 elf_section_data (o)->rel_count = 0;
7869 elf_section_data (o)->rel_count2 = 0;
7872 _bfd_elf_assign_file_positions_for_relocs (abfd);
7874 /* We have now assigned file positions for all the sections except
7875 .symtab and .strtab. We start the .symtab section at the current
7876 file position, and write directly to it. We build the .strtab
7877 section in memory. */
7878 bfd_get_symcount (abfd) = 0;
7879 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
7880 /* sh_name is set in prep_headers. */
7881 symtab_hdr->sh_type = SHT_SYMTAB;
7882 /* sh_flags, sh_addr and sh_size all start off zero. */
7883 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
7884 /* sh_link is set in assign_section_numbers. */
7885 /* sh_info is set below. */
7886 /* sh_offset is set just below. */
7887 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
7889 off = elf_tdata (abfd)->next_file_pos;
7890 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
7892 /* Note that at this point elf_tdata (abfd)->next_file_pos is
7893 incorrect. We do not yet know the size of the .symtab section.
7894 We correct next_file_pos below, after we do know the size. */
7896 /* Allocate a buffer to hold swapped out symbols. This is to avoid
7897 continuously seeking to the right position in the file. */
7898 if (! info->keep_memory || max_sym_count < 20)
7899 finfo.symbuf_size = 20;
7900 else
7901 finfo.symbuf_size = max_sym_count;
7902 amt = finfo.symbuf_size;
7903 amt *= bed->s->sizeof_sym;
7904 finfo.symbuf = bfd_malloc (amt);
7905 if (finfo.symbuf == NULL)
7906 goto error_return;
7907 if (elf_numsections (abfd) > SHN_LORESERVE)
7909 /* Wild guess at number of output symbols. realloc'd as needed. */
7910 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
7911 finfo.shndxbuf_size = amt;
7912 amt *= sizeof (Elf_External_Sym_Shndx);
7913 finfo.symshndxbuf = bfd_zmalloc (amt);
7914 if (finfo.symshndxbuf == NULL)
7915 goto error_return;
7918 /* Start writing out the symbol table. The first symbol is always a
7919 dummy symbol. */
7920 if (info->strip != strip_all
7921 || emit_relocs)
7923 elfsym.st_value = 0;
7924 elfsym.st_size = 0;
7925 elfsym.st_info = 0;
7926 elfsym.st_other = 0;
7927 elfsym.st_shndx = SHN_UNDEF;
7928 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
7929 NULL))
7930 goto error_return;
7933 /* Output a symbol for each section. We output these even if we are
7934 discarding local symbols, since they are used for relocs. These
7935 symbols have no names. We store the index of each one in the
7936 index field of the section, so that we can find it again when
7937 outputting relocs. */
7938 if (info->strip != strip_all
7939 || emit_relocs)
7941 elfsym.st_size = 0;
7942 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
7943 elfsym.st_other = 0;
7944 for (i = 1; i < elf_numsections (abfd); i++)
7946 o = bfd_section_from_elf_index (abfd, i);
7947 if (o != NULL)
7948 o->target_index = bfd_get_symcount (abfd);
7949 elfsym.st_shndx = i;
7950 if (info->relocatable || o == NULL)
7951 elfsym.st_value = 0;
7952 else
7953 elfsym.st_value = o->vma;
7954 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
7955 goto error_return;
7956 if (i == SHN_LORESERVE - 1)
7957 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
7961 /* Allocate some memory to hold information read in from the input
7962 files. */
7963 if (max_contents_size != 0)
7965 finfo.contents = bfd_malloc (max_contents_size);
7966 if (finfo.contents == NULL)
7967 goto error_return;
7970 if (max_external_reloc_size != 0)
7972 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
7973 if (finfo.external_relocs == NULL)
7974 goto error_return;
7977 if (max_internal_reloc_count != 0)
7979 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
7980 amt *= sizeof (Elf_Internal_Rela);
7981 finfo.internal_relocs = bfd_malloc (amt);
7982 if (finfo.internal_relocs == NULL)
7983 goto error_return;
7986 if (max_sym_count != 0)
7988 amt = max_sym_count * bed->s->sizeof_sym;
7989 finfo.external_syms = bfd_malloc (amt);
7990 if (finfo.external_syms == NULL)
7991 goto error_return;
7993 amt = max_sym_count * sizeof (Elf_Internal_Sym);
7994 finfo.internal_syms = bfd_malloc (amt);
7995 if (finfo.internal_syms == NULL)
7996 goto error_return;
7998 amt = max_sym_count * sizeof (long);
7999 finfo.indices = bfd_malloc (amt);
8000 if (finfo.indices == NULL)
8001 goto error_return;
8003 amt = max_sym_count * sizeof (asection *);
8004 finfo.sections = bfd_malloc (amt);
8005 if (finfo.sections == NULL)
8006 goto error_return;
8009 if (max_sym_shndx_count != 0)
8011 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8012 finfo.locsym_shndx = bfd_malloc (amt);
8013 if (finfo.locsym_shndx == NULL)
8014 goto error_return;
8017 if (elf_hash_table (info)->tls_sec)
8019 bfd_vma base, end = 0;
8020 asection *sec;
8022 for (sec = elf_hash_table (info)->tls_sec;
8023 sec && (sec->flags & SEC_THREAD_LOCAL);
8024 sec = sec->next)
8026 bfd_vma size = sec->size;
8028 if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8030 struct bfd_link_order *o;
8032 for (o = sec->link_order_head; o != NULL; o = o->next)
8033 if (size < o->offset + o->size)
8034 size = o->offset + o->size;
8036 end = sec->vma + size;
8038 base = elf_hash_table (info)->tls_sec->vma;
8039 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8040 elf_hash_table (info)->tls_size = end - base;
8043 /* Reorder SHF_LINK_ORDER sections. */
8044 for (o = abfd->sections; o != NULL; o = o->next)
8046 if (!elf_fixup_link_order (abfd, o))
8047 return FALSE;
8050 /* Since ELF permits relocations to be against local symbols, we
8051 must have the local symbols available when we do the relocations.
8052 Since we would rather only read the local symbols once, and we
8053 would rather not keep them in memory, we handle all the
8054 relocations for a single input file at the same time.
8056 Unfortunately, there is no way to know the total number of local
8057 symbols until we have seen all of them, and the local symbol
8058 indices precede the global symbol indices. This means that when
8059 we are generating relocatable output, and we see a reloc against
8060 a global symbol, we can not know the symbol index until we have
8061 finished examining all the local symbols to see which ones we are
8062 going to output. To deal with this, we keep the relocations in
8063 memory, and don't output them until the end of the link. This is
8064 an unfortunate waste of memory, but I don't see a good way around
8065 it. Fortunately, it only happens when performing a relocatable
8066 link, which is not the common case. FIXME: If keep_memory is set
8067 we could write the relocs out and then read them again; I don't
8068 know how bad the memory loss will be. */
8070 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8071 sub->output_has_begun = FALSE;
8072 for (o = abfd->sections; o != NULL; o = o->next)
8074 for (p = o->link_order_head; p != NULL; p = p->next)
8076 if (p->type == bfd_indirect_link_order
8077 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8078 == bfd_target_elf_flavour)
8079 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8081 if (! sub->output_has_begun)
8083 if (! elf_link_input_bfd (&finfo, sub))
8084 goto error_return;
8085 sub->output_has_begun = TRUE;
8088 else if (p->type == bfd_section_reloc_link_order
8089 || p->type == bfd_symbol_reloc_link_order)
8091 if (! elf_reloc_link_order (abfd, info, o, p))
8092 goto error_return;
8094 else
8096 if (! _bfd_default_link_order (abfd, info, o, p))
8097 goto error_return;
8102 /* Output any global symbols that got converted to local in a
8103 version script or due to symbol visibility. We do this in a
8104 separate step since ELF requires all local symbols to appear
8105 prior to any global symbols. FIXME: We should only do this if
8106 some global symbols were, in fact, converted to become local.
8107 FIXME: Will this work correctly with the Irix 5 linker? */
8108 eoinfo.failed = FALSE;
8109 eoinfo.finfo = &finfo;
8110 eoinfo.localsyms = TRUE;
8111 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8112 &eoinfo);
8113 if (eoinfo.failed)
8114 return FALSE;
8116 /* That wrote out all the local symbols. Finish up the symbol table
8117 with the global symbols. Even if we want to strip everything we
8118 can, we still need to deal with those global symbols that got
8119 converted to local in a version script. */
8121 /* The sh_info field records the index of the first non local symbol. */
8122 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8124 if (dynamic
8125 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8127 Elf_Internal_Sym sym;
8128 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8129 long last_local = 0;
8131 /* Write out the section symbols for the output sections. */
8132 if (info->shared)
8134 asection *s;
8136 sym.st_size = 0;
8137 sym.st_name = 0;
8138 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8139 sym.st_other = 0;
8141 for (s = abfd->sections; s != NULL; s = s->next)
8143 int indx;
8144 bfd_byte *dest;
8145 long dynindx;
8147 dynindx = elf_section_data (s)->dynindx;
8148 if (dynindx <= 0)
8149 continue;
8150 indx = elf_section_data (s)->this_idx;
8151 BFD_ASSERT (indx > 0);
8152 sym.st_shndx = indx;
8153 sym.st_value = s->vma;
8154 dest = dynsym + dynindx * bed->s->sizeof_sym;
8155 if (last_local < dynindx)
8156 last_local = dynindx;
8157 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8161 /* Write out the local dynsyms. */
8162 if (elf_hash_table (info)->dynlocal)
8164 struct elf_link_local_dynamic_entry *e;
8165 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8167 asection *s;
8168 bfd_byte *dest;
8170 sym.st_size = e->isym.st_size;
8171 sym.st_other = e->isym.st_other;
8173 /* Copy the internal symbol as is.
8174 Note that we saved a word of storage and overwrote
8175 the original st_name with the dynstr_index. */
8176 sym = e->isym;
8178 if (e->isym.st_shndx != SHN_UNDEF
8179 && (e->isym.st_shndx < SHN_LORESERVE
8180 || e->isym.st_shndx > SHN_HIRESERVE))
8182 s = bfd_section_from_elf_index (e->input_bfd,
8183 e->isym.st_shndx);
8185 sym.st_shndx =
8186 elf_section_data (s->output_section)->this_idx;
8187 sym.st_value = (s->output_section->vma
8188 + s->output_offset
8189 + e->isym.st_value);
8192 if (last_local < e->dynindx)
8193 last_local = e->dynindx;
8195 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8196 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8200 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8201 last_local + 1;
8204 /* We get the global symbols from the hash table. */
8205 eoinfo.failed = FALSE;
8206 eoinfo.localsyms = FALSE;
8207 eoinfo.finfo = &finfo;
8208 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8209 &eoinfo);
8210 if (eoinfo.failed)
8211 return FALSE;
8213 /* If backend needs to output some symbols not present in the hash
8214 table, do it now. */
8215 if (bed->elf_backend_output_arch_syms)
8217 typedef bfd_boolean (*out_sym_func)
8218 (void *, const char *, Elf_Internal_Sym *, asection *,
8219 struct elf_link_hash_entry *);
8221 if (! ((*bed->elf_backend_output_arch_syms)
8222 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8223 return FALSE;
8226 /* Flush all symbols to the file. */
8227 if (! elf_link_flush_output_syms (&finfo, bed))
8228 return FALSE;
8230 /* Now we know the size of the symtab section. */
8231 off += symtab_hdr->sh_size;
8233 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8234 if (symtab_shndx_hdr->sh_name != 0)
8236 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8237 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8238 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8239 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8240 symtab_shndx_hdr->sh_size = amt;
8242 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8243 off, TRUE);
8245 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8246 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8247 return FALSE;
8251 /* Finish up and write out the symbol string table (.strtab)
8252 section. */
8253 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8254 /* sh_name was set in prep_headers. */
8255 symstrtab_hdr->sh_type = SHT_STRTAB;
8256 symstrtab_hdr->sh_flags = 0;
8257 symstrtab_hdr->sh_addr = 0;
8258 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8259 symstrtab_hdr->sh_entsize = 0;
8260 symstrtab_hdr->sh_link = 0;
8261 symstrtab_hdr->sh_info = 0;
8262 /* sh_offset is set just below. */
8263 symstrtab_hdr->sh_addralign = 1;
8265 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8266 elf_tdata (abfd)->next_file_pos = off;
8268 if (bfd_get_symcount (abfd) > 0)
8270 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8271 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8272 return FALSE;
8275 /* Adjust the relocs to have the correct symbol indices. */
8276 for (o = abfd->sections; o != NULL; o = o->next)
8278 if ((o->flags & SEC_RELOC) == 0)
8279 continue;
8281 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8282 elf_section_data (o)->rel_count,
8283 elf_section_data (o)->rel_hashes);
8284 if (elf_section_data (o)->rel_hdr2 != NULL)
8285 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8286 elf_section_data (o)->rel_count2,
8287 (elf_section_data (o)->rel_hashes
8288 + elf_section_data (o)->rel_count));
8290 /* Set the reloc_count field to 0 to prevent write_relocs from
8291 trying to swap the relocs out itself. */
8292 o->reloc_count = 0;
8295 if (dynamic && info->combreloc && dynobj != NULL)
8296 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8298 /* If we are linking against a dynamic object, or generating a
8299 shared library, finish up the dynamic linking information. */
8300 if (dynamic)
8302 bfd_byte *dyncon, *dynconend;
8304 /* Fix up .dynamic entries. */
8305 o = bfd_get_section_by_name (dynobj, ".dynamic");
8306 BFD_ASSERT (o != NULL);
8308 dyncon = o->contents;
8309 dynconend = o->contents + o->size;
8310 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8312 Elf_Internal_Dyn dyn;
8313 const char *name;
8314 unsigned int type;
8316 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8318 switch (dyn.d_tag)
8320 default:
8321 continue;
8322 case DT_NULL:
8323 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8325 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8327 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8328 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8329 default: continue;
8331 dyn.d_un.d_val = relativecount;
8332 relativecount = 0;
8333 break;
8335 continue;
8337 case DT_INIT:
8338 name = info->init_function;
8339 goto get_sym;
8340 case DT_FINI:
8341 name = info->fini_function;
8342 get_sym:
8344 struct elf_link_hash_entry *h;
8346 h = elf_link_hash_lookup (elf_hash_table (info), name,
8347 FALSE, FALSE, TRUE);
8348 if (h != NULL
8349 && (h->root.type == bfd_link_hash_defined
8350 || h->root.type == bfd_link_hash_defweak))
8352 dyn.d_un.d_val = h->root.u.def.value;
8353 o = h->root.u.def.section;
8354 if (o->output_section != NULL)
8355 dyn.d_un.d_val += (o->output_section->vma
8356 + o->output_offset);
8357 else
8359 /* The symbol is imported from another shared
8360 library and does not apply to this one. */
8361 dyn.d_un.d_val = 0;
8363 break;
8366 continue;
8368 case DT_PREINIT_ARRAYSZ:
8369 name = ".preinit_array";
8370 goto get_size;
8371 case DT_INIT_ARRAYSZ:
8372 name = ".init_array";
8373 goto get_size;
8374 case DT_FINI_ARRAYSZ:
8375 name = ".fini_array";
8376 get_size:
8377 o = bfd_get_section_by_name (abfd, name);
8378 if (o == NULL)
8380 (*_bfd_error_handler)
8381 (_("%B: could not find output section %s"), abfd, name);
8382 goto error_return;
8384 if (o->size == 0)
8385 (*_bfd_error_handler)
8386 (_("warning: %s section has zero size"), name);
8387 dyn.d_un.d_val = o->size;
8388 break;
8390 case DT_PREINIT_ARRAY:
8391 name = ".preinit_array";
8392 goto get_vma;
8393 case DT_INIT_ARRAY:
8394 name = ".init_array";
8395 goto get_vma;
8396 case DT_FINI_ARRAY:
8397 name = ".fini_array";
8398 goto get_vma;
8400 case DT_HASH:
8401 name = ".hash";
8402 goto get_vma;
8403 case DT_STRTAB:
8404 name = ".dynstr";
8405 goto get_vma;
8406 case DT_SYMTAB:
8407 name = ".dynsym";
8408 goto get_vma;
8409 case DT_VERDEF:
8410 name = ".gnu.version_d";
8411 goto get_vma;
8412 case DT_VERNEED:
8413 name = ".gnu.version_r";
8414 goto get_vma;
8415 case DT_VERSYM:
8416 name = ".gnu.version";
8417 get_vma:
8418 o = bfd_get_section_by_name (abfd, name);
8419 if (o == NULL)
8421 (*_bfd_error_handler)
8422 (_("%B: could not find output section %s"), abfd, name);
8423 goto error_return;
8425 dyn.d_un.d_ptr = o->vma;
8426 break;
8428 case DT_REL:
8429 case DT_RELA:
8430 case DT_RELSZ:
8431 case DT_RELASZ:
8432 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8433 type = SHT_REL;
8434 else
8435 type = SHT_RELA;
8436 dyn.d_un.d_val = 0;
8437 for (i = 1; i < elf_numsections (abfd); i++)
8439 Elf_Internal_Shdr *hdr;
8441 hdr = elf_elfsections (abfd)[i];
8442 if (hdr->sh_type == type
8443 && (hdr->sh_flags & SHF_ALLOC) != 0)
8445 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8446 dyn.d_un.d_val += hdr->sh_size;
8447 else
8449 if (dyn.d_un.d_val == 0
8450 || hdr->sh_addr < dyn.d_un.d_val)
8451 dyn.d_un.d_val = hdr->sh_addr;
8455 break;
8457 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8461 /* If we have created any dynamic sections, then output them. */
8462 if (dynobj != NULL)
8464 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8465 goto error_return;
8467 for (o = dynobj->sections; o != NULL; o = o->next)
8469 if ((o->flags & SEC_HAS_CONTENTS) == 0
8470 || o->size == 0
8471 || o->output_section == bfd_abs_section_ptr)
8472 continue;
8473 if ((o->flags & SEC_LINKER_CREATED) == 0)
8475 /* At this point, we are only interested in sections
8476 created by _bfd_elf_link_create_dynamic_sections. */
8477 continue;
8479 if (elf_hash_table (info)->stab_info.stabstr == o)
8480 continue;
8481 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8482 continue;
8483 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8484 != SHT_STRTAB)
8485 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8487 if (! bfd_set_section_contents (abfd, o->output_section,
8488 o->contents,
8489 (file_ptr) o->output_offset,
8490 o->size))
8491 goto error_return;
8493 else
8495 /* The contents of the .dynstr section are actually in a
8496 stringtab. */
8497 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8498 if (bfd_seek (abfd, off, SEEK_SET) != 0
8499 || ! _bfd_elf_strtab_emit (abfd,
8500 elf_hash_table (info)->dynstr))
8501 goto error_return;
8506 if (info->relocatable)
8508 bfd_boolean failed = FALSE;
8510 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8511 if (failed)
8512 goto error_return;
8515 /* If we have optimized stabs strings, output them. */
8516 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8518 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8519 goto error_return;
8522 if (info->eh_frame_hdr)
8524 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8525 goto error_return;
8528 if (finfo.symstrtab != NULL)
8529 _bfd_stringtab_free (finfo.symstrtab);
8530 if (finfo.contents != NULL)
8531 free (finfo.contents);
8532 if (finfo.external_relocs != NULL)
8533 free (finfo.external_relocs);
8534 if (finfo.internal_relocs != NULL)
8535 free (finfo.internal_relocs);
8536 if (finfo.external_syms != NULL)
8537 free (finfo.external_syms);
8538 if (finfo.locsym_shndx != NULL)
8539 free (finfo.locsym_shndx);
8540 if (finfo.internal_syms != NULL)
8541 free (finfo.internal_syms);
8542 if (finfo.indices != NULL)
8543 free (finfo.indices);
8544 if (finfo.sections != NULL)
8545 free (finfo.sections);
8546 if (finfo.symbuf != NULL)
8547 free (finfo.symbuf);
8548 if (finfo.symshndxbuf != NULL)
8549 free (finfo.symshndxbuf);
8550 for (o = abfd->sections; o != NULL; o = o->next)
8552 if ((o->flags & SEC_RELOC) != 0
8553 && elf_section_data (o)->rel_hashes != NULL)
8554 free (elf_section_data (o)->rel_hashes);
8557 elf_tdata (abfd)->linker = TRUE;
8559 return TRUE;
8561 error_return:
8562 if (finfo.symstrtab != NULL)
8563 _bfd_stringtab_free (finfo.symstrtab);
8564 if (finfo.contents != NULL)
8565 free (finfo.contents);
8566 if (finfo.external_relocs != NULL)
8567 free (finfo.external_relocs);
8568 if (finfo.internal_relocs != NULL)
8569 free (finfo.internal_relocs);
8570 if (finfo.external_syms != NULL)
8571 free (finfo.external_syms);
8572 if (finfo.locsym_shndx != NULL)
8573 free (finfo.locsym_shndx);
8574 if (finfo.internal_syms != NULL)
8575 free (finfo.internal_syms);
8576 if (finfo.indices != NULL)
8577 free (finfo.indices);
8578 if (finfo.sections != NULL)
8579 free (finfo.sections);
8580 if (finfo.symbuf != NULL)
8581 free (finfo.symbuf);
8582 if (finfo.symshndxbuf != NULL)
8583 free (finfo.symshndxbuf);
8584 for (o = abfd->sections; o != NULL; o = o->next)
8586 if ((o->flags & SEC_RELOC) != 0
8587 && elf_section_data (o)->rel_hashes != NULL)
8588 free (elf_section_data (o)->rel_hashes);
8591 return FALSE;
8594 /* Garbage collect unused sections. */
8596 /* The mark phase of garbage collection. For a given section, mark
8597 it and any sections in this section's group, and all the sections
8598 which define symbols to which it refers. */
8600 typedef asection * (*gc_mark_hook_fn)
8601 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8602 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8604 bfd_boolean
8605 _bfd_elf_gc_mark (struct bfd_link_info *info,
8606 asection *sec,
8607 gc_mark_hook_fn gc_mark_hook)
8609 bfd_boolean ret;
8610 asection *group_sec;
8612 sec->gc_mark = 1;
8614 /* Mark all the sections in the group. */
8615 group_sec = elf_section_data (sec)->next_in_group;
8616 if (group_sec && !group_sec->gc_mark)
8617 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
8618 return FALSE;
8620 /* Look through the section relocs. */
8621 ret = TRUE;
8622 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8624 Elf_Internal_Rela *relstart, *rel, *relend;
8625 Elf_Internal_Shdr *symtab_hdr;
8626 struct elf_link_hash_entry **sym_hashes;
8627 size_t nlocsyms;
8628 size_t extsymoff;
8629 bfd *input_bfd = sec->owner;
8630 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8631 Elf_Internal_Sym *isym = NULL;
8632 int r_sym_shift;
8634 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8635 sym_hashes = elf_sym_hashes (input_bfd);
8637 /* Read the local symbols. */
8638 if (elf_bad_symtab (input_bfd))
8640 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8641 extsymoff = 0;
8643 else
8644 extsymoff = nlocsyms = symtab_hdr->sh_info;
8646 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8647 if (isym == NULL && nlocsyms != 0)
8649 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8650 NULL, NULL, NULL);
8651 if (isym == NULL)
8652 return FALSE;
8655 /* Read the relocations. */
8656 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8657 info->keep_memory);
8658 if (relstart == NULL)
8660 ret = FALSE;
8661 goto out1;
8663 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8665 if (bed->s->arch_size == 32)
8666 r_sym_shift = 8;
8667 else
8668 r_sym_shift = 32;
8670 for (rel = relstart; rel < relend; rel++)
8672 unsigned long r_symndx;
8673 asection *rsec;
8674 struct elf_link_hash_entry *h;
8676 r_symndx = rel->r_info >> r_sym_shift;
8677 if (r_symndx == 0)
8678 continue;
8680 if (r_symndx >= nlocsyms
8681 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8683 h = sym_hashes[r_symndx - extsymoff];
8684 while (h->root.type == bfd_link_hash_indirect
8685 || h->root.type == bfd_link_hash_warning)
8686 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8687 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8689 else
8691 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8694 if (rsec && !rsec->gc_mark)
8696 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8697 rsec->gc_mark = 1;
8698 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
8700 ret = FALSE;
8701 goto out2;
8706 out2:
8707 if (elf_section_data (sec)->relocs != relstart)
8708 free (relstart);
8709 out1:
8710 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8712 if (! info->keep_memory)
8713 free (isym);
8714 else
8715 symtab_hdr->contents = (unsigned char *) isym;
8719 return ret;
8722 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8724 static bfd_boolean
8725 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
8727 int *idx = idxptr;
8729 if (h->root.type == bfd_link_hash_warning)
8730 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8732 if (h->dynindx != -1
8733 && ((h->root.type != bfd_link_hash_defined
8734 && h->root.type != bfd_link_hash_defweak)
8735 || h->root.u.def.section->gc_mark))
8736 h->dynindx = (*idx)++;
8738 return TRUE;
8741 /* The sweep phase of garbage collection. Remove all garbage sections. */
8743 typedef bfd_boolean (*gc_sweep_hook_fn)
8744 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8746 static bfd_boolean
8747 elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
8749 bfd *sub;
8751 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8753 asection *o;
8755 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8756 continue;
8758 for (o = sub->sections; o != NULL; o = o->next)
8760 /* Keep debug and special sections. */
8761 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
8762 || (o->flags & (SEC_ALLOC | SEC_LOAD)) == 0)
8763 o->gc_mark = 1;
8765 if (o->gc_mark)
8766 continue;
8768 /* Skip sweeping sections already excluded. */
8769 if (o->flags & SEC_EXCLUDE)
8770 continue;
8772 /* Since this is early in the link process, it is simple
8773 to remove a section from the output. */
8774 o->flags |= SEC_EXCLUDE;
8776 /* But we also have to update some of the relocation
8777 info we collected before. */
8778 if (gc_sweep_hook
8779 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
8781 Elf_Internal_Rela *internal_relocs;
8782 bfd_boolean r;
8784 internal_relocs
8785 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8786 info->keep_memory);
8787 if (internal_relocs == NULL)
8788 return FALSE;
8790 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8792 if (elf_section_data (o)->relocs != internal_relocs)
8793 free (internal_relocs);
8795 if (!r)
8796 return FALSE;
8801 /* Remove the symbols that were in the swept sections from the dynamic
8802 symbol table. GCFIXME: Anyone know how to get them out of the
8803 static symbol table as well? */
8805 int i = 0;
8807 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
8809 elf_hash_table (info)->dynsymcount = i;
8812 return TRUE;
8815 /* Propagate collected vtable information. This is called through
8816 elf_link_hash_traverse. */
8818 static bfd_boolean
8819 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
8821 if (h->root.type == bfd_link_hash_warning)
8822 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8824 /* Those that are not vtables. */
8825 if (h->vtable == NULL || h->vtable->parent == NULL)
8826 return TRUE;
8828 /* Those vtables that do not have parents, we cannot merge. */
8829 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
8830 return TRUE;
8832 /* If we've already been done, exit. */
8833 if (h->vtable->used && h->vtable->used[-1])
8834 return TRUE;
8836 /* Make sure the parent's table is up to date. */
8837 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
8839 if (h->vtable->used == NULL)
8841 /* None of this table's entries were referenced. Re-use the
8842 parent's table. */
8843 h->vtable->used = h->vtable->parent->vtable->used;
8844 h->vtable->size = h->vtable->parent->vtable->size;
8846 else
8848 size_t n;
8849 bfd_boolean *cu, *pu;
8851 /* Or the parent's entries into ours. */
8852 cu = h->vtable->used;
8853 cu[-1] = TRUE;
8854 pu = h->vtable->parent->vtable->used;
8855 if (pu != NULL)
8857 const struct elf_backend_data *bed;
8858 unsigned int log_file_align;
8860 bed = get_elf_backend_data (h->root.u.def.section->owner);
8861 log_file_align = bed->s->log_file_align;
8862 n = h->vtable->parent->vtable->size >> log_file_align;
8863 while (n--)
8865 if (*pu)
8866 *cu = TRUE;
8867 pu++;
8868 cu++;
8873 return TRUE;
8876 static bfd_boolean
8877 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
8879 asection *sec;
8880 bfd_vma hstart, hend;
8881 Elf_Internal_Rela *relstart, *relend, *rel;
8882 const struct elf_backend_data *bed;
8883 unsigned int log_file_align;
8885 if (h->root.type == bfd_link_hash_warning)
8886 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8888 /* Take care of both those symbols that do not describe vtables as
8889 well as those that are not loaded. */
8890 if (h->vtable == NULL || h->vtable->parent == NULL)
8891 return TRUE;
8893 BFD_ASSERT (h->root.type == bfd_link_hash_defined
8894 || h->root.type == bfd_link_hash_defweak);
8896 sec = h->root.u.def.section;
8897 hstart = h->root.u.def.value;
8898 hend = hstart + h->size;
8900 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
8901 if (!relstart)
8902 return *(bfd_boolean *) okp = FALSE;
8903 bed = get_elf_backend_data (sec->owner);
8904 log_file_align = bed->s->log_file_align;
8906 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8908 for (rel = relstart; rel < relend; ++rel)
8909 if (rel->r_offset >= hstart && rel->r_offset < hend)
8911 /* If the entry is in use, do nothing. */
8912 if (h->vtable->used
8913 && (rel->r_offset - hstart) < h->vtable->size)
8915 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
8916 if (h->vtable->used[entry])
8917 continue;
8919 /* Otherwise, kill it. */
8920 rel->r_offset = rel->r_info = rel->r_addend = 0;
8923 return TRUE;
8926 /* Mark sections containing dynamically referenced symbols. This is called
8927 through elf_link_hash_traverse. */
8929 static bfd_boolean
8930 elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h,
8931 void *okp ATTRIBUTE_UNUSED)
8933 if (h->root.type == bfd_link_hash_warning)
8934 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8936 if ((h->root.type == bfd_link_hash_defined
8937 || h->root.type == bfd_link_hash_defweak)
8938 && h->ref_dynamic)
8939 h->root.u.def.section->flags |= SEC_KEEP;
8941 return TRUE;
8944 /* Do mark and sweep of unused sections. */
8946 bfd_boolean
8947 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
8949 bfd_boolean ok = TRUE;
8950 bfd *sub;
8951 asection * (*gc_mark_hook)
8952 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8953 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
8955 if (!get_elf_backend_data (abfd)->can_gc_sections
8956 || info->relocatable
8957 || info->emitrelocations
8958 || info->shared
8959 || !is_elf_hash_table (info->hash))
8961 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
8962 return TRUE;
8965 /* Apply transitive closure to the vtable entry usage info. */
8966 elf_link_hash_traverse (elf_hash_table (info),
8967 elf_gc_propagate_vtable_entries_used,
8968 &ok);
8969 if (!ok)
8970 return FALSE;
8972 /* Kill the vtable relocations that were not used. */
8973 elf_link_hash_traverse (elf_hash_table (info),
8974 elf_gc_smash_unused_vtentry_relocs,
8975 &ok);
8976 if (!ok)
8977 return FALSE;
8979 /* Mark dynamically referenced symbols. */
8980 if (elf_hash_table (info)->dynamic_sections_created)
8981 elf_link_hash_traverse (elf_hash_table (info),
8982 elf_gc_mark_dynamic_ref_symbol,
8983 &ok);
8984 if (!ok)
8985 return FALSE;
8987 /* Grovel through relocs to find out who stays ... */
8988 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
8989 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8991 asection *o;
8993 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8994 continue;
8996 for (o = sub->sections; o != NULL; o = o->next)
8998 if (o->flags & SEC_KEEP)
9000 /* _bfd_elf_discard_section_eh_frame knows how to discard
9001 orphaned FDEs so don't mark sections referenced by the
9002 EH frame section. */
9003 if (strcmp (o->name, ".eh_frame") == 0)
9004 o->gc_mark = 1;
9005 else if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9006 return FALSE;
9011 /* ... and mark SEC_EXCLUDE for those that go. */
9012 if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
9013 return FALSE;
9015 return TRUE;
9018 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9020 bfd_boolean
9021 bfd_elf_gc_record_vtinherit (bfd *abfd,
9022 asection *sec,
9023 struct elf_link_hash_entry *h,
9024 bfd_vma offset)
9026 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9027 struct elf_link_hash_entry **search, *child;
9028 bfd_size_type extsymcount;
9029 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9031 /* The sh_info field of the symtab header tells us where the
9032 external symbols start. We don't care about the local symbols at
9033 this point. */
9034 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9035 if (!elf_bad_symtab (abfd))
9036 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9038 sym_hashes = elf_sym_hashes (abfd);
9039 sym_hashes_end = sym_hashes + extsymcount;
9041 /* Hunt down the child symbol, which is in this section at the same
9042 offset as the relocation. */
9043 for (search = sym_hashes; search != sym_hashes_end; ++search)
9045 if ((child = *search) != NULL
9046 && (child->root.type == bfd_link_hash_defined
9047 || child->root.type == bfd_link_hash_defweak)
9048 && child->root.u.def.section == sec
9049 && child->root.u.def.value == offset)
9050 goto win;
9053 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9054 abfd, sec, (unsigned long) offset);
9055 bfd_set_error (bfd_error_invalid_operation);
9056 return FALSE;
9058 win:
9059 if (!child->vtable)
9061 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9062 if (!child->vtable)
9063 return FALSE;
9065 if (!h)
9067 /* This *should* only be the absolute section. It could potentially
9068 be that someone has defined a non-global vtable though, which
9069 would be bad. It isn't worth paging in the local symbols to be
9070 sure though; that case should simply be handled by the assembler. */
9072 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9074 else
9075 child->vtable->parent = h;
9077 return TRUE;
9080 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9082 bfd_boolean
9083 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9084 asection *sec ATTRIBUTE_UNUSED,
9085 struct elf_link_hash_entry *h,
9086 bfd_vma addend)
9088 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9089 unsigned int log_file_align = bed->s->log_file_align;
9091 if (!h->vtable)
9093 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9094 if (!h->vtable)
9095 return FALSE;
9098 if (addend >= h->vtable->size)
9100 size_t size, bytes, file_align;
9101 bfd_boolean *ptr = h->vtable->used;
9103 /* While the symbol is undefined, we have to be prepared to handle
9104 a zero size. */
9105 file_align = 1 << log_file_align;
9106 if (h->root.type == bfd_link_hash_undefined)
9107 size = addend + file_align;
9108 else
9110 size = h->size;
9111 if (addend >= size)
9113 /* Oops! We've got a reference past the defined end of
9114 the table. This is probably a bug -- shall we warn? */
9115 size = addend + file_align;
9118 size = (size + file_align - 1) & -file_align;
9120 /* Allocate one extra entry for use as a "done" flag for the
9121 consolidation pass. */
9122 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9124 if (ptr)
9126 ptr = bfd_realloc (ptr - 1, bytes);
9128 if (ptr != NULL)
9130 size_t oldbytes;
9132 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9133 * sizeof (bfd_boolean));
9134 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9137 else
9138 ptr = bfd_zmalloc (bytes);
9140 if (ptr == NULL)
9141 return FALSE;
9143 /* And arrange for that done flag to be at index -1. */
9144 h->vtable->used = ptr + 1;
9145 h->vtable->size = size;
9148 h->vtable->used[addend >> log_file_align] = TRUE;
9150 return TRUE;
9153 struct alloc_got_off_arg {
9154 bfd_vma gotoff;
9155 unsigned int got_elt_size;
9158 /* We need a special top-level link routine to convert got reference counts
9159 to real got offsets. */
9161 static bfd_boolean
9162 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
9164 struct alloc_got_off_arg *gofarg = arg;
9166 if (h->root.type == bfd_link_hash_warning)
9167 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9169 if (h->got.refcount > 0)
9171 h->got.offset = gofarg->gotoff;
9172 gofarg->gotoff += gofarg->got_elt_size;
9174 else
9175 h->got.offset = (bfd_vma) -1;
9177 return TRUE;
9180 /* And an accompanying bit to work out final got entry offsets once
9181 we're done. Should be called from final_link. */
9183 bfd_boolean
9184 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
9185 struct bfd_link_info *info)
9187 bfd *i;
9188 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9189 bfd_vma gotoff;
9190 unsigned int got_elt_size = bed->s->arch_size / 8;
9191 struct alloc_got_off_arg gofarg;
9193 if (! is_elf_hash_table (info->hash))
9194 return FALSE;
9196 /* The GOT offset is relative to the .got section, but the GOT header is
9197 put into the .got.plt section, if the backend uses it. */
9198 if (bed->want_got_plt)
9199 gotoff = 0;
9200 else
9201 gotoff = bed->got_header_size;
9203 /* Do the local .got entries first. */
9204 for (i = info->input_bfds; i; i = i->link_next)
9206 bfd_signed_vma *local_got;
9207 bfd_size_type j, locsymcount;
9208 Elf_Internal_Shdr *symtab_hdr;
9210 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
9211 continue;
9213 local_got = elf_local_got_refcounts (i);
9214 if (!local_got)
9215 continue;
9217 symtab_hdr = &elf_tdata (i)->symtab_hdr;
9218 if (elf_bad_symtab (i))
9219 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9220 else
9221 locsymcount = symtab_hdr->sh_info;
9223 for (j = 0; j < locsymcount; ++j)
9225 if (local_got[j] > 0)
9227 local_got[j] = gotoff;
9228 gotoff += got_elt_size;
9230 else
9231 local_got[j] = (bfd_vma) -1;
9235 /* Then the global .got entries. .plt refcounts are handled by
9236 adjust_dynamic_symbol */
9237 gofarg.gotoff = gotoff;
9238 gofarg.got_elt_size = got_elt_size;
9239 elf_link_hash_traverse (elf_hash_table (info),
9240 elf_gc_allocate_got_offsets,
9241 &gofarg);
9242 return TRUE;
9245 /* Many folk need no more in the way of final link than this, once
9246 got entry reference counting is enabled. */
9248 bfd_boolean
9249 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
9251 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
9252 return FALSE;
9254 /* Invoke the regular ELF backend linker to do all the work. */
9255 return bfd_elf_final_link (abfd, info);
9258 bfd_boolean
9259 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
9261 struct elf_reloc_cookie *rcookie = cookie;
9263 if (rcookie->bad_symtab)
9264 rcookie->rel = rcookie->rels;
9266 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9268 unsigned long r_symndx;
9270 if (! rcookie->bad_symtab)
9271 if (rcookie->rel->r_offset > offset)
9272 return FALSE;
9273 if (rcookie->rel->r_offset != offset)
9274 continue;
9276 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9277 if (r_symndx == SHN_UNDEF)
9278 return TRUE;
9280 if (r_symndx >= rcookie->locsymcount
9281 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9283 struct elf_link_hash_entry *h;
9285 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9287 while (h->root.type == bfd_link_hash_indirect
9288 || h->root.type == bfd_link_hash_warning)
9289 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9291 if ((h->root.type == bfd_link_hash_defined
9292 || h->root.type == bfd_link_hash_defweak)
9293 && elf_discarded_section (h->root.u.def.section))
9294 return TRUE;
9295 else
9296 return FALSE;
9298 else
9300 /* It's not a relocation against a global symbol,
9301 but it could be a relocation against a local
9302 symbol for a discarded section. */
9303 asection *isec;
9304 Elf_Internal_Sym *isym;
9306 /* Need to: get the symbol; get the section. */
9307 isym = &rcookie->locsyms[r_symndx];
9308 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9310 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9311 if (isec != NULL && elf_discarded_section (isec))
9312 return TRUE;
9315 return FALSE;
9317 return FALSE;
9320 /* Discard unneeded references to discarded sections.
9321 Returns TRUE if any section's size was changed. */
9322 /* This function assumes that the relocations are in sorted order,
9323 which is true for all known assemblers. */
9325 bfd_boolean
9326 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9328 struct elf_reloc_cookie cookie;
9329 asection *stab, *eh;
9330 Elf_Internal_Shdr *symtab_hdr;
9331 const struct elf_backend_data *bed;
9332 bfd *abfd;
9333 unsigned int count;
9334 bfd_boolean ret = FALSE;
9336 if (info->traditional_format
9337 || !is_elf_hash_table (info->hash))
9338 return FALSE;
9340 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9342 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9343 continue;
9345 bed = get_elf_backend_data (abfd);
9347 if ((abfd->flags & DYNAMIC) != 0)
9348 continue;
9350 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9351 if (info->relocatable
9352 || (eh != NULL
9353 && (eh->size == 0
9354 || bfd_is_abs_section (eh->output_section))))
9355 eh = NULL;
9357 stab = bfd_get_section_by_name (abfd, ".stab");
9358 if (stab != NULL
9359 && (stab->size == 0
9360 || bfd_is_abs_section (stab->output_section)
9361 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9362 stab = NULL;
9364 if (stab == NULL
9365 && eh == NULL
9366 && bed->elf_backend_discard_info == NULL)
9367 continue;
9369 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9370 cookie.abfd = abfd;
9371 cookie.sym_hashes = elf_sym_hashes (abfd);
9372 cookie.bad_symtab = elf_bad_symtab (abfd);
9373 if (cookie.bad_symtab)
9375 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9376 cookie.extsymoff = 0;
9378 else
9380 cookie.locsymcount = symtab_hdr->sh_info;
9381 cookie.extsymoff = symtab_hdr->sh_info;
9384 if (bed->s->arch_size == 32)
9385 cookie.r_sym_shift = 8;
9386 else
9387 cookie.r_sym_shift = 32;
9389 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9390 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9392 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9393 cookie.locsymcount, 0,
9394 NULL, NULL, NULL);
9395 if (cookie.locsyms == NULL)
9396 return FALSE;
9399 if (stab != NULL)
9401 cookie.rels = NULL;
9402 count = stab->reloc_count;
9403 if (count != 0)
9404 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9405 info->keep_memory);
9406 if (cookie.rels != NULL)
9408 cookie.rel = cookie.rels;
9409 cookie.relend = cookie.rels;
9410 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9411 if (_bfd_discard_section_stabs (abfd, stab,
9412 elf_section_data (stab)->sec_info,
9413 bfd_elf_reloc_symbol_deleted_p,
9414 &cookie))
9415 ret = TRUE;
9416 if (elf_section_data (stab)->relocs != cookie.rels)
9417 free (cookie.rels);
9421 if (eh != NULL)
9423 cookie.rels = NULL;
9424 count = eh->reloc_count;
9425 if (count != 0)
9426 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9427 info->keep_memory);
9428 cookie.rel = cookie.rels;
9429 cookie.relend = cookie.rels;
9430 if (cookie.rels != NULL)
9431 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9433 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9434 bfd_elf_reloc_symbol_deleted_p,
9435 &cookie))
9436 ret = TRUE;
9438 if (cookie.rels != NULL
9439 && elf_section_data (eh)->relocs != cookie.rels)
9440 free (cookie.rels);
9443 if (bed->elf_backend_discard_info != NULL
9444 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9445 ret = TRUE;
9447 if (cookie.locsyms != NULL
9448 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9450 if (! info->keep_memory)
9451 free (cookie.locsyms);
9452 else
9453 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9457 if (info->eh_frame_hdr
9458 && !info->relocatable
9459 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9460 ret = TRUE;
9462 return ret;
9465 void
9466 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9468 flagword flags;
9469 const char *name, *p;
9470 struct bfd_section_already_linked *l;
9471 struct bfd_section_already_linked_hash_entry *already_linked_list;
9472 asection *group;
9474 /* A single member comdat group section may be discarded by a
9475 linkonce section. See below. */
9476 if (sec->output_section == bfd_abs_section_ptr)
9477 return;
9479 flags = sec->flags;
9481 /* Check if it belongs to a section group. */
9482 group = elf_sec_group (sec);
9484 /* Return if it isn't a linkonce section nor a member of a group. A
9485 comdat group section also has SEC_LINK_ONCE set. */
9486 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9487 return;
9489 if (group)
9491 /* If this is the member of a single member comdat group, check if
9492 the group should be discarded. */
9493 if (elf_next_in_group (sec) == sec
9494 && (group->flags & SEC_LINK_ONCE) != 0)
9495 sec = group;
9496 else
9497 return;
9500 /* FIXME: When doing a relocatable link, we may have trouble
9501 copying relocations in other sections that refer to local symbols
9502 in the section being discarded. Those relocations will have to
9503 be converted somehow; as of this writing I'm not sure that any of
9504 the backends handle that correctly.
9506 It is tempting to instead not discard link once sections when
9507 doing a relocatable link (technically, they should be discarded
9508 whenever we are building constructors). However, that fails,
9509 because the linker winds up combining all the link once sections
9510 into a single large link once section, which defeats the purpose
9511 of having link once sections in the first place.
9513 Also, not merging link once sections in a relocatable link
9514 causes trouble for MIPS ELF, which relies on link once semantics
9515 to handle the .reginfo section correctly. */
9517 name = bfd_get_section_name (abfd, sec);
9519 if (strncmp (name, ".gnu.linkonce.", sizeof (".gnu.linkonce.") - 1) == 0
9520 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
9521 p++;
9522 else
9523 p = name;
9525 already_linked_list = bfd_section_already_linked_table_lookup (p);
9527 for (l = already_linked_list->entry; l != NULL; l = l->next)
9529 /* We may have 3 different sections on the list: group section,
9530 comdat section and linkonce section. SEC may be a linkonce or
9531 group section. We match a group section with a group section,
9532 a linkonce section with a linkonce section, and ignore comdat
9533 section. */
9534 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9535 && strcmp (name, l->sec->name) == 0
9536 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9538 /* The section has already been linked. See if we should
9539 issue a warning. */
9540 switch (flags & SEC_LINK_DUPLICATES)
9542 default:
9543 abort ();
9545 case SEC_LINK_DUPLICATES_DISCARD:
9546 break;
9548 case SEC_LINK_DUPLICATES_ONE_ONLY:
9549 (*_bfd_error_handler)
9550 (_("%B: ignoring duplicate section `%A'\n"),
9551 abfd, sec);
9552 break;
9554 case SEC_LINK_DUPLICATES_SAME_SIZE:
9555 if (sec->size != l->sec->size)
9556 (*_bfd_error_handler)
9557 (_("%B: duplicate section `%A' has different size\n"),
9558 abfd, sec);
9559 break;
9561 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
9562 if (sec->size != l->sec->size)
9563 (*_bfd_error_handler)
9564 (_("%B: duplicate section `%A' has different size\n"),
9565 abfd, sec);
9566 else if (sec->size != 0)
9568 bfd_byte *sec_contents, *l_sec_contents;
9570 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
9571 (*_bfd_error_handler)
9572 (_("%B: warning: could not read contents of section `%A'\n"),
9573 abfd, sec);
9574 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
9575 &l_sec_contents))
9576 (*_bfd_error_handler)
9577 (_("%B: warning: could not read contents of section `%A'\n"),
9578 l->sec->owner, l->sec);
9579 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
9580 (*_bfd_error_handler)
9581 (_("%B: warning: duplicate section `%A' has different contents\n"),
9582 abfd, sec);
9584 if (sec_contents)
9585 free (sec_contents);
9586 if (l_sec_contents)
9587 free (l_sec_contents);
9589 break;
9592 /* Set the output_section field so that lang_add_section
9593 does not create a lang_input_section structure for this
9594 section. Since there might be a symbol in the section
9595 being discarded, we must retain a pointer to the section
9596 which we are really going to use. */
9597 sec->output_section = bfd_abs_section_ptr;
9598 sec->kept_section = l->sec;
9600 if (flags & SEC_GROUP)
9602 asection *first = elf_next_in_group (sec);
9603 asection *s = first;
9605 while (s != NULL)
9607 s->output_section = bfd_abs_section_ptr;
9608 /* Record which group discards it. */
9609 s->kept_section = l->sec;
9610 s = elf_next_in_group (s);
9611 /* These lists are circular. */
9612 if (s == first)
9613 break;
9617 return;
9621 if (group)
9623 /* If this is the member of a single member comdat group and the
9624 group hasn't be discarded, we check if it matches a linkonce
9625 section. We only record the discarded comdat group. Otherwise
9626 the undiscarded group will be discarded incorrectly later since
9627 itself has been recorded. */
9628 for (l = already_linked_list->entry; l != NULL; l = l->next)
9629 if ((l->sec->flags & SEC_GROUP) == 0
9630 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9631 && bfd_elf_match_symbols_in_sections (l->sec,
9632 elf_next_in_group (sec)))
9634 elf_next_in_group (sec)->output_section = bfd_abs_section_ptr;
9635 elf_next_in_group (sec)->kept_section = l->sec;
9636 group->output_section = bfd_abs_section_ptr;
9637 break;
9639 if (l == NULL)
9640 return;
9642 else
9643 /* There is no direct match. But for linkonce section, we should
9644 check if there is a match with comdat group member. We always
9645 record the linkonce section, discarded or not. */
9646 for (l = already_linked_list->entry; l != NULL; l = l->next)
9647 if (l->sec->flags & SEC_GROUP)
9649 asection *first = elf_next_in_group (l->sec);
9651 if (first != NULL
9652 && elf_next_in_group (first) == first
9653 && bfd_elf_match_symbols_in_sections (first, sec))
9655 sec->output_section = bfd_abs_section_ptr;
9656 sec->kept_section = l->sec;
9657 break;
9661 /* This is the first section with this name. Record it. */
9662 bfd_section_already_linked_table_insert (already_linked_list, sec);