* libbfd-in.h (_bfd_ar_spacepad): New prototype.
[binutils.git] / bfd / elflink.c
blob1721f3f8a3c478a55cf1bf60dd6d5605032ec393
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 if (!elf_hash_table (info)->is_relocatable_executable)
390 return TRUE;
393 default:
394 break;
397 h->dynindx = elf_hash_table (info)->dynsymcount;
398 ++elf_hash_table (info)->dynsymcount;
400 dynstr = elf_hash_table (info)->dynstr;
401 if (dynstr == NULL)
403 /* Create a strtab to hold the dynamic symbol names. */
404 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
405 if (dynstr == NULL)
406 return FALSE;
409 /* We don't put any version information in the dynamic string
410 table. */
411 name = h->root.root.string;
412 p = strchr (name, ELF_VER_CHR);
413 if (p != NULL)
414 /* We know that the p points into writable memory. In fact,
415 there are only a few symbols that have read-only names, being
416 those like _GLOBAL_OFFSET_TABLE_ that are created specially
417 by the backends. Most symbols will have names pointing into
418 an ELF string table read from a file, or to objalloc memory. */
419 *p = 0;
421 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
423 if (p != NULL)
424 *p = ELF_VER_CHR;
426 if (indx == (bfd_size_type) -1)
427 return FALSE;
428 h->dynstr_index = indx;
431 return TRUE;
434 /* Record an assignment to a symbol made by a linker script. We need
435 this in case some dynamic object refers to this symbol. */
437 bfd_boolean
438 bfd_elf_record_link_assignment (bfd *output_bfd ATTRIBUTE_UNUSED,
439 struct bfd_link_info *info,
440 const char *name,
441 bfd_boolean provide)
443 struct elf_link_hash_entry *h;
444 struct elf_link_hash_table *htab;
446 if (!is_elf_hash_table (info->hash))
447 return TRUE;
449 htab = elf_hash_table (info);
450 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
451 if (h == NULL)
452 return provide;
454 /* Since we're defining the symbol, don't let it seem to have not
455 been defined. record_dynamic_symbol and size_dynamic_sections
456 may depend on this. */
457 if (h->root.type == bfd_link_hash_undefweak
458 || h->root.type == bfd_link_hash_undefined)
460 h->root.type = bfd_link_hash_new;
461 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
462 bfd_link_repair_undef_list (&htab->root);
465 if (h->root.type == bfd_link_hash_new)
466 h->non_elf = 0;
468 /* If this symbol is being provided by the linker script, and it is
469 currently defined by a dynamic object, but not by a regular
470 object, then mark it as undefined so that the generic linker will
471 force the correct value. */
472 if (provide
473 && h->def_dynamic
474 && !h->def_regular)
475 h->root.type = bfd_link_hash_undefined;
477 /* If this symbol is not being provided by the linker script, and it is
478 currently defined by a dynamic object, but not by a regular object,
479 then clear out any version information because the symbol will not be
480 associated with the dynamic object any more. */
481 if (!provide
482 && h->def_dynamic
483 && !h->def_regular)
484 h->verinfo.verdef = NULL;
486 h->def_regular = 1;
488 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
489 and executables. */
490 if (!info->relocatable
491 && h->dynindx != -1
492 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
493 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
494 h->forced_local = 1;
496 if ((h->def_dynamic
497 || h->ref_dynamic
498 || info->shared
499 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
500 && h->dynindx == -1)
502 if (! bfd_elf_link_record_dynamic_symbol (info, h))
503 return FALSE;
505 /* If this is a weak defined symbol, and we know a corresponding
506 real symbol from the same dynamic object, make sure the real
507 symbol is also made into a dynamic symbol. */
508 if (h->u.weakdef != NULL
509 && h->u.weakdef->dynindx == -1)
511 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
512 return FALSE;
516 return TRUE;
519 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
520 success, and 2 on a failure caused by attempting to record a symbol
521 in a discarded section, eg. a discarded link-once section symbol. */
524 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
525 bfd *input_bfd,
526 long input_indx)
528 bfd_size_type amt;
529 struct elf_link_local_dynamic_entry *entry;
530 struct elf_link_hash_table *eht;
531 struct elf_strtab_hash *dynstr;
532 unsigned long dynstr_index;
533 char *name;
534 Elf_External_Sym_Shndx eshndx;
535 char esym[sizeof (Elf64_External_Sym)];
537 if (! is_elf_hash_table (info->hash))
538 return 0;
540 /* See if the entry exists already. */
541 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
542 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
543 return 1;
545 amt = sizeof (*entry);
546 entry = bfd_alloc (input_bfd, amt);
547 if (entry == NULL)
548 return 0;
550 /* Go find the symbol, so that we can find it's name. */
551 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
552 1, input_indx, &entry->isym, esym, &eshndx))
554 bfd_release (input_bfd, entry);
555 return 0;
558 if (entry->isym.st_shndx != SHN_UNDEF
559 && (entry->isym.st_shndx < SHN_LORESERVE
560 || entry->isym.st_shndx > SHN_HIRESERVE))
562 asection *s;
564 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
565 if (s == NULL || bfd_is_abs_section (s->output_section))
567 /* We can still bfd_release here as nothing has done another
568 bfd_alloc. We can't do this later in this function. */
569 bfd_release (input_bfd, entry);
570 return 2;
574 name = (bfd_elf_string_from_elf_section
575 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
576 entry->isym.st_name));
578 dynstr = elf_hash_table (info)->dynstr;
579 if (dynstr == NULL)
581 /* Create a strtab to hold the dynamic symbol names. */
582 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
583 if (dynstr == NULL)
584 return 0;
587 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
588 if (dynstr_index == (unsigned long) -1)
589 return 0;
590 entry->isym.st_name = dynstr_index;
592 eht = elf_hash_table (info);
594 entry->next = eht->dynlocal;
595 eht->dynlocal = entry;
596 entry->input_bfd = input_bfd;
597 entry->input_indx = input_indx;
598 eht->dynsymcount++;
600 /* Whatever binding the symbol had before, it's now local. */
601 entry->isym.st_info
602 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
604 /* The dynindx will be set at the end of size_dynamic_sections. */
606 return 1;
609 /* Return the dynindex of a local dynamic symbol. */
611 long
612 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
613 bfd *input_bfd,
614 long input_indx)
616 struct elf_link_local_dynamic_entry *e;
618 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
619 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
620 return e->dynindx;
621 return -1;
624 /* This function is used to renumber the dynamic symbols, if some of
625 them are removed because they are marked as local. This is called
626 via elf_link_hash_traverse. */
628 static bfd_boolean
629 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
630 void *data)
632 size_t *count = data;
634 if (h->root.type == bfd_link_hash_warning)
635 h = (struct elf_link_hash_entry *) h->root.u.i.link;
637 if (h->forced_local)
638 return TRUE;
640 if (h->dynindx != -1)
641 h->dynindx = ++(*count);
643 return TRUE;
647 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
648 STB_LOCAL binding. */
650 static bfd_boolean
651 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
652 void *data)
654 size_t *count = data;
656 if (h->root.type == bfd_link_hash_warning)
657 h = (struct elf_link_hash_entry *) h->root.u.i.link;
659 if (!h->forced_local)
660 return TRUE;
662 if (h->dynindx != -1)
663 h->dynindx = ++(*count);
665 return TRUE;
668 /* Return true if the dynamic symbol for a given section should be
669 omitted when creating a shared library. */
670 bfd_boolean
671 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
672 struct bfd_link_info *info,
673 asection *p)
675 switch (elf_section_data (p)->this_hdr.sh_type)
677 case SHT_PROGBITS:
678 case SHT_NOBITS:
679 /* If sh_type is yet undecided, assume it could be
680 SHT_PROGBITS/SHT_NOBITS. */
681 case SHT_NULL:
682 if (strcmp (p->name, ".got") == 0
683 || strcmp (p->name, ".got.plt") == 0
684 || strcmp (p->name, ".plt") == 0)
686 asection *ip;
687 bfd *dynobj = elf_hash_table (info)->dynobj;
689 if (dynobj != NULL
690 && (ip = bfd_get_section_by_name (dynobj, p->name)) != NULL
691 && (ip->flags & SEC_LINKER_CREATED)
692 && ip->output_section == p)
693 return TRUE;
695 return FALSE;
697 /* There shouldn't be section relative relocations
698 against any other section. */
699 default:
700 return TRUE;
704 /* Assign dynsym indices. In a shared library we generate a section
705 symbol for each output section, which come first. Next come symbols
706 which have been forced to local binding. Then all of the back-end
707 allocated local dynamic syms, followed by the rest of the global
708 symbols. */
710 unsigned long
711 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd, struct bfd_link_info *info)
713 unsigned long dynsymcount = 0;
715 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
717 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
718 asection *p;
719 for (p = output_bfd->sections; p ; p = p->next)
720 if ((p->flags & SEC_EXCLUDE) == 0
721 && (p->flags & SEC_ALLOC) != 0
722 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
723 elf_section_data (p)->dynindx = ++dynsymcount;
726 elf_link_hash_traverse (elf_hash_table (info),
727 elf_link_renumber_local_hash_table_dynsyms,
728 &dynsymcount);
730 if (elf_hash_table (info)->dynlocal)
732 struct elf_link_local_dynamic_entry *p;
733 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
734 p->dynindx = ++dynsymcount;
737 elf_link_hash_traverse (elf_hash_table (info),
738 elf_link_renumber_hash_table_dynsyms,
739 &dynsymcount);
741 /* There is an unused NULL entry at the head of the table which
742 we must account for in our count. Unless there weren't any
743 symbols, which means we'll have no table at all. */
744 if (dynsymcount != 0)
745 ++dynsymcount;
747 return elf_hash_table (info)->dynsymcount = dynsymcount;
750 /* This function is called when we want to define a new symbol. It
751 handles the various cases which arise when we find a definition in
752 a dynamic object, or when there is already a definition in a
753 dynamic object. The new symbol is described by NAME, SYM, PSEC,
754 and PVALUE. We set SYM_HASH to the hash table entry. We set
755 OVERRIDE if the old symbol is overriding a new definition. We set
756 TYPE_CHANGE_OK if it is OK for the type to change. We set
757 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
758 change, we mean that we shouldn't warn if the type or size does
759 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
760 object is overridden by a regular object. */
762 bfd_boolean
763 _bfd_elf_merge_symbol (bfd *abfd,
764 struct bfd_link_info *info,
765 const char *name,
766 Elf_Internal_Sym *sym,
767 asection **psec,
768 bfd_vma *pvalue,
769 unsigned int *pold_alignment,
770 struct elf_link_hash_entry **sym_hash,
771 bfd_boolean *skip,
772 bfd_boolean *override,
773 bfd_boolean *type_change_ok,
774 bfd_boolean *size_change_ok)
776 asection *sec, *oldsec;
777 struct elf_link_hash_entry *h;
778 struct elf_link_hash_entry *flip;
779 int bind;
780 bfd *oldbfd;
781 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
782 bfd_boolean newweak, oldweak;
784 *skip = FALSE;
785 *override = FALSE;
787 sec = *psec;
788 bind = ELF_ST_BIND (sym->st_info);
790 if (! bfd_is_und_section (sec))
791 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
792 else
793 h = ((struct elf_link_hash_entry *)
794 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
795 if (h == NULL)
796 return FALSE;
797 *sym_hash = h;
799 /* This code is for coping with dynamic objects, and is only useful
800 if we are doing an ELF link. */
801 if (info->hash->creator != abfd->xvec)
802 return TRUE;
804 /* For merging, we only care about real symbols. */
806 while (h->root.type == bfd_link_hash_indirect
807 || h->root.type == bfd_link_hash_warning)
808 h = (struct elf_link_hash_entry *) h->root.u.i.link;
810 /* If we just created the symbol, mark it as being an ELF symbol.
811 Other than that, there is nothing to do--there is no merge issue
812 with a newly defined symbol--so we just return. */
814 if (h->root.type == bfd_link_hash_new)
816 h->non_elf = 0;
817 return TRUE;
820 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
821 existing symbol. */
823 switch (h->root.type)
825 default:
826 oldbfd = NULL;
827 oldsec = NULL;
828 break;
830 case bfd_link_hash_undefined:
831 case bfd_link_hash_undefweak:
832 oldbfd = h->root.u.undef.abfd;
833 oldsec = NULL;
834 break;
836 case bfd_link_hash_defined:
837 case bfd_link_hash_defweak:
838 oldbfd = h->root.u.def.section->owner;
839 oldsec = h->root.u.def.section;
840 break;
842 case bfd_link_hash_common:
843 oldbfd = h->root.u.c.p->section->owner;
844 oldsec = h->root.u.c.p->section;
845 break;
848 /* In cases involving weak versioned symbols, we may wind up trying
849 to merge a symbol with itself. Catch that here, to avoid the
850 confusion that results if we try to override a symbol with
851 itself. The additional tests catch cases like
852 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
853 dynamic object, which we do want to handle here. */
854 if (abfd == oldbfd
855 && ((abfd->flags & DYNAMIC) == 0
856 || !h->def_regular))
857 return TRUE;
859 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
860 respectively, is from a dynamic object. */
862 if ((abfd->flags & DYNAMIC) != 0)
863 newdyn = TRUE;
864 else
865 newdyn = FALSE;
867 if (oldbfd != NULL)
868 olddyn = (oldbfd->flags & DYNAMIC) != 0;
869 else
871 asection *hsec;
873 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
874 indices used by MIPS ELF. */
875 switch (h->root.type)
877 default:
878 hsec = NULL;
879 break;
881 case bfd_link_hash_defined:
882 case bfd_link_hash_defweak:
883 hsec = h->root.u.def.section;
884 break;
886 case bfd_link_hash_common:
887 hsec = h->root.u.c.p->section;
888 break;
891 if (hsec == NULL)
892 olddyn = FALSE;
893 else
894 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
897 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
898 respectively, appear to be a definition rather than reference. */
900 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
901 newdef = FALSE;
902 else
903 newdef = TRUE;
905 if (h->root.type == bfd_link_hash_undefined
906 || h->root.type == bfd_link_hash_undefweak
907 || h->root.type == bfd_link_hash_common)
908 olddef = FALSE;
909 else
910 olddef = TRUE;
912 /* Check TLS symbol. */
913 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
914 && ELF_ST_TYPE (sym->st_info) != h->type)
916 bfd *ntbfd, *tbfd;
917 bfd_boolean ntdef, tdef;
918 asection *ntsec, *tsec;
920 if (h->type == STT_TLS)
922 ntbfd = abfd;
923 ntsec = sec;
924 ntdef = newdef;
925 tbfd = oldbfd;
926 tsec = oldsec;
927 tdef = olddef;
929 else
931 ntbfd = oldbfd;
932 ntsec = oldsec;
933 ntdef = olddef;
934 tbfd = abfd;
935 tsec = sec;
936 tdef = newdef;
939 if (tdef && ntdef)
940 (*_bfd_error_handler)
941 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
942 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
943 else if (!tdef && !ntdef)
944 (*_bfd_error_handler)
945 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
946 tbfd, ntbfd, h->root.root.string);
947 else if (tdef)
948 (*_bfd_error_handler)
949 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
950 tbfd, tsec, ntbfd, h->root.root.string);
951 else
952 (*_bfd_error_handler)
953 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
954 tbfd, ntbfd, ntsec, h->root.root.string);
956 bfd_set_error (bfd_error_bad_value);
957 return FALSE;
960 /* We need to remember if a symbol has a definition in a dynamic
961 object or is weak in all dynamic objects. Internal and hidden
962 visibility will make it unavailable to dynamic objects. */
963 if (newdyn && !h->dynamic_def)
965 if (!bfd_is_und_section (sec))
966 h->dynamic_def = 1;
967 else
969 /* Check if this symbol is weak in all dynamic objects. If it
970 is the first time we see it in a dynamic object, we mark
971 if it is weak. Otherwise, we clear it. */
972 if (!h->ref_dynamic)
974 if (bind == STB_WEAK)
975 h->dynamic_weak = 1;
977 else if (bind != STB_WEAK)
978 h->dynamic_weak = 0;
982 /* If the old symbol has non-default visibility, we ignore the new
983 definition from a dynamic object. */
984 if (newdyn
985 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
986 && !bfd_is_und_section (sec))
988 *skip = TRUE;
989 /* Make sure this symbol is dynamic. */
990 h->ref_dynamic = 1;
991 /* A protected symbol has external availability. Make sure it is
992 recorded as dynamic.
994 FIXME: Should we check type and size for protected symbol? */
995 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
996 return bfd_elf_link_record_dynamic_symbol (info, h);
997 else
998 return TRUE;
1000 else if (!newdyn
1001 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1002 && h->def_dynamic)
1004 /* If the new symbol with non-default visibility comes from a
1005 relocatable file and the old definition comes from a dynamic
1006 object, we remove the old definition. */
1007 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1008 h = *sym_hash;
1010 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1011 && bfd_is_und_section (sec))
1013 /* If the new symbol is undefined and the old symbol was
1014 also undefined before, we need to make sure
1015 _bfd_generic_link_add_one_symbol doesn't mess
1016 up the linker hash table undefs list. Since the old
1017 definition came from a dynamic object, it is still on the
1018 undefs list. */
1019 h->root.type = bfd_link_hash_undefined;
1020 h->root.u.undef.abfd = abfd;
1022 else
1024 h->root.type = bfd_link_hash_new;
1025 h->root.u.undef.abfd = NULL;
1028 if (h->def_dynamic)
1030 h->def_dynamic = 0;
1031 h->ref_dynamic = 1;
1032 h->dynamic_def = 1;
1034 /* FIXME: Should we check type and size for protected symbol? */
1035 h->size = 0;
1036 h->type = 0;
1037 return TRUE;
1040 /* Differentiate strong and weak symbols. */
1041 newweak = bind == STB_WEAK;
1042 oldweak = (h->root.type == bfd_link_hash_defweak
1043 || h->root.type == bfd_link_hash_undefweak);
1045 /* If a new weak symbol definition comes from a regular file and the
1046 old symbol comes from a dynamic library, we treat the new one as
1047 strong. Similarly, an old weak symbol definition from a regular
1048 file is treated as strong when the new symbol comes from a dynamic
1049 library. Further, an old weak symbol from a dynamic library is
1050 treated as strong if the new symbol is from a dynamic library.
1051 This reflects the way glibc's ld.so works.
1053 Do this before setting *type_change_ok or *size_change_ok so that
1054 we warn properly when dynamic library symbols are overridden. */
1056 if (newdef && !newdyn && olddyn)
1057 newweak = FALSE;
1058 if (olddef && newdyn)
1059 oldweak = FALSE;
1061 /* It's OK to change the type if either the existing symbol or the
1062 new symbol is weak. A type change is also OK if the old symbol
1063 is undefined and the new symbol is defined. */
1065 if (oldweak
1066 || newweak
1067 || (newdef
1068 && h->root.type == bfd_link_hash_undefined))
1069 *type_change_ok = TRUE;
1071 /* It's OK to change the size if either the existing symbol or the
1072 new symbol is weak, or if the old symbol is undefined. */
1074 if (*type_change_ok
1075 || h->root.type == bfd_link_hash_undefined)
1076 *size_change_ok = TRUE;
1078 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1079 symbol, respectively, appears to be a common symbol in a dynamic
1080 object. If a symbol appears in an uninitialized section, and is
1081 not weak, and is not a function, then it may be a common symbol
1082 which was resolved when the dynamic object was created. We want
1083 to treat such symbols specially, because they raise special
1084 considerations when setting the symbol size: if the symbol
1085 appears as a common symbol in a regular object, and the size in
1086 the regular object is larger, we must make sure that we use the
1087 larger size. This problematic case can always be avoided in C,
1088 but it must be handled correctly when using Fortran shared
1089 libraries.
1091 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1092 likewise for OLDDYNCOMMON and OLDDEF.
1094 Note that this test is just a heuristic, and that it is quite
1095 possible to have an uninitialized symbol in a shared object which
1096 is really a definition, rather than a common symbol. This could
1097 lead to some minor confusion when the symbol really is a common
1098 symbol in some regular object. However, I think it will be
1099 harmless. */
1101 if (newdyn
1102 && newdef
1103 && !newweak
1104 && (sec->flags & SEC_ALLOC) != 0
1105 && (sec->flags & SEC_LOAD) == 0
1106 && sym->st_size > 0
1107 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1108 newdyncommon = TRUE;
1109 else
1110 newdyncommon = FALSE;
1112 if (olddyn
1113 && olddef
1114 && h->root.type == bfd_link_hash_defined
1115 && h->def_dynamic
1116 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1117 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1118 && h->size > 0
1119 && h->type != STT_FUNC)
1120 olddyncommon = TRUE;
1121 else
1122 olddyncommon = FALSE;
1124 /* If both the old and the new symbols look like common symbols in a
1125 dynamic object, set the size of the symbol to the larger of the
1126 two. */
1128 if (olddyncommon
1129 && newdyncommon
1130 && sym->st_size != h->size)
1132 /* Since we think we have two common symbols, issue a multiple
1133 common warning if desired. Note that we only warn if the
1134 size is different. If the size is the same, we simply let
1135 the old symbol override the new one as normally happens with
1136 symbols defined in dynamic objects. */
1138 if (! ((*info->callbacks->multiple_common)
1139 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1140 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1141 return FALSE;
1143 if (sym->st_size > h->size)
1144 h->size = sym->st_size;
1146 *size_change_ok = TRUE;
1149 /* If we are looking at a dynamic object, and we have found a
1150 definition, we need to see if the symbol was already defined by
1151 some other object. If so, we want to use the existing
1152 definition, and we do not want to report a multiple symbol
1153 definition error; we do this by clobbering *PSEC to be
1154 bfd_und_section_ptr.
1156 We treat a common symbol as a definition if the symbol in the
1157 shared library is a function, since common symbols always
1158 represent variables; this can cause confusion in principle, but
1159 any such confusion would seem to indicate an erroneous program or
1160 shared library. We also permit a common symbol in a regular
1161 object to override a weak symbol in a shared object. */
1163 if (newdyn
1164 && newdef
1165 && (olddef
1166 || (h->root.type == bfd_link_hash_common
1167 && (newweak
1168 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1170 *override = TRUE;
1171 newdef = FALSE;
1172 newdyncommon = FALSE;
1174 *psec = sec = bfd_und_section_ptr;
1175 *size_change_ok = TRUE;
1177 /* If we get here when the old symbol is a common symbol, then
1178 we are explicitly letting it override a weak symbol or
1179 function in a dynamic object, and we don't want to warn about
1180 a type change. If the old symbol is a defined symbol, a type
1181 change warning may still be appropriate. */
1183 if (h->root.type == bfd_link_hash_common)
1184 *type_change_ok = TRUE;
1187 /* Handle the special case of an old common symbol merging with a
1188 new symbol which looks like a common symbol in a shared object.
1189 We change *PSEC and *PVALUE to make the new symbol look like a
1190 common symbol, and let _bfd_generic_link_add_one_symbol will do
1191 the right thing. */
1193 if (newdyncommon
1194 && h->root.type == bfd_link_hash_common)
1196 *override = TRUE;
1197 newdef = FALSE;
1198 newdyncommon = FALSE;
1199 *pvalue = sym->st_size;
1200 *psec = sec = bfd_com_section_ptr;
1201 *size_change_ok = TRUE;
1204 /* If the old symbol is from a dynamic object, and the new symbol is
1205 a definition which is not from a dynamic object, then the new
1206 symbol overrides the old symbol. Symbols from regular files
1207 always take precedence over symbols from dynamic objects, even if
1208 they are defined after the dynamic object in the link.
1210 As above, we again permit a common symbol in a regular object to
1211 override a definition in a shared object if the shared object
1212 symbol is a function or is weak. */
1214 flip = NULL;
1215 if (!newdyn
1216 && (newdef
1217 || (bfd_is_com_section (sec)
1218 && (oldweak
1219 || h->type == STT_FUNC)))
1220 && olddyn
1221 && olddef
1222 && h->def_dynamic)
1224 /* Change the hash table entry to undefined, and let
1225 _bfd_generic_link_add_one_symbol do the right thing with the
1226 new definition. */
1228 h->root.type = bfd_link_hash_undefined;
1229 h->root.u.undef.abfd = h->root.u.def.section->owner;
1230 *size_change_ok = TRUE;
1232 olddef = FALSE;
1233 olddyncommon = FALSE;
1235 /* We again permit a type change when a common symbol may be
1236 overriding a function. */
1238 if (bfd_is_com_section (sec))
1239 *type_change_ok = TRUE;
1241 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1242 flip = *sym_hash;
1243 else
1244 /* This union may have been set to be non-NULL when this symbol
1245 was seen in a dynamic object. We must force the union to be
1246 NULL, so that it is correct for a regular symbol. */
1247 h->verinfo.vertree = NULL;
1250 /* Handle the special case of a new common symbol merging with an
1251 old symbol that looks like it might be a common symbol defined in
1252 a shared object. Note that we have already handled the case in
1253 which a new common symbol should simply override the definition
1254 in the shared library. */
1256 if (! newdyn
1257 && bfd_is_com_section (sec)
1258 && olddyncommon)
1260 /* It would be best if we could set the hash table entry to a
1261 common symbol, but we don't know what to use for the section
1262 or the alignment. */
1263 if (! ((*info->callbacks->multiple_common)
1264 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1265 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1266 return FALSE;
1268 /* If the presumed common symbol in the dynamic object is
1269 larger, pretend that the new symbol has its size. */
1271 if (h->size > *pvalue)
1272 *pvalue = h->size;
1274 /* We need to remember the alignment required by the symbol
1275 in the dynamic object. */
1276 BFD_ASSERT (pold_alignment);
1277 *pold_alignment = h->root.u.def.section->alignment_power;
1279 olddef = FALSE;
1280 olddyncommon = FALSE;
1282 h->root.type = bfd_link_hash_undefined;
1283 h->root.u.undef.abfd = h->root.u.def.section->owner;
1285 *size_change_ok = TRUE;
1286 *type_change_ok = TRUE;
1288 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1289 flip = *sym_hash;
1290 else
1291 h->verinfo.vertree = NULL;
1294 if (flip != NULL)
1296 /* Handle the case where we had a versioned symbol in a dynamic
1297 library and now find a definition in a normal object. In this
1298 case, we make the versioned symbol point to the normal one. */
1299 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1300 flip->root.type = h->root.type;
1301 h->root.type = bfd_link_hash_indirect;
1302 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1303 (*bed->elf_backend_copy_indirect_symbol) (bed, flip, h);
1304 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1305 if (h->def_dynamic)
1307 h->def_dynamic = 0;
1308 flip->ref_dynamic = 1;
1312 return TRUE;
1315 /* This function is called to create an indirect symbol from the
1316 default for the symbol with the default version if needed. The
1317 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1318 set DYNSYM if the new indirect symbol is dynamic. */
1320 bfd_boolean
1321 _bfd_elf_add_default_symbol (bfd *abfd,
1322 struct bfd_link_info *info,
1323 struct elf_link_hash_entry *h,
1324 const char *name,
1325 Elf_Internal_Sym *sym,
1326 asection **psec,
1327 bfd_vma *value,
1328 bfd_boolean *dynsym,
1329 bfd_boolean override)
1331 bfd_boolean type_change_ok;
1332 bfd_boolean size_change_ok;
1333 bfd_boolean skip;
1334 char *shortname;
1335 struct elf_link_hash_entry *hi;
1336 struct bfd_link_hash_entry *bh;
1337 const struct elf_backend_data *bed;
1338 bfd_boolean collect;
1339 bfd_boolean dynamic;
1340 char *p;
1341 size_t len, shortlen;
1342 asection *sec;
1344 /* If this symbol has a version, and it is the default version, we
1345 create an indirect symbol from the default name to the fully
1346 decorated name. This will cause external references which do not
1347 specify a version to be bound to this version of the symbol. */
1348 p = strchr (name, ELF_VER_CHR);
1349 if (p == NULL || p[1] != ELF_VER_CHR)
1350 return TRUE;
1352 if (override)
1354 /* We are overridden by an old definition. We need to check if we
1355 need to create the indirect symbol from the default name. */
1356 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1357 FALSE, FALSE);
1358 BFD_ASSERT (hi != NULL);
1359 if (hi == h)
1360 return TRUE;
1361 while (hi->root.type == bfd_link_hash_indirect
1362 || hi->root.type == bfd_link_hash_warning)
1364 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1365 if (hi == h)
1366 return TRUE;
1370 bed = get_elf_backend_data (abfd);
1371 collect = bed->collect;
1372 dynamic = (abfd->flags & DYNAMIC) != 0;
1374 shortlen = p - name;
1375 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1376 if (shortname == NULL)
1377 return FALSE;
1378 memcpy (shortname, name, shortlen);
1379 shortname[shortlen] = '\0';
1381 /* We are going to create a new symbol. Merge it with any existing
1382 symbol with this name. For the purposes of the merge, act as
1383 though we were defining the symbol we just defined, although we
1384 actually going to define an indirect symbol. */
1385 type_change_ok = FALSE;
1386 size_change_ok = FALSE;
1387 sec = *psec;
1388 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1389 NULL, &hi, &skip, &override,
1390 &type_change_ok, &size_change_ok))
1391 return FALSE;
1393 if (skip)
1394 goto nondefault;
1396 if (! override)
1398 bh = &hi->root;
1399 if (! (_bfd_generic_link_add_one_symbol
1400 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1401 0, name, FALSE, collect, &bh)))
1402 return FALSE;
1403 hi = (struct elf_link_hash_entry *) bh;
1405 else
1407 /* In this case the symbol named SHORTNAME is overriding the
1408 indirect symbol we want to add. We were planning on making
1409 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1410 is the name without a version. NAME is the fully versioned
1411 name, and it is the default version.
1413 Overriding means that we already saw a definition for the
1414 symbol SHORTNAME in a regular object, and it is overriding
1415 the symbol defined in the dynamic object.
1417 When this happens, we actually want to change NAME, the
1418 symbol we just added, to refer to SHORTNAME. This will cause
1419 references to NAME in the shared object to become references
1420 to SHORTNAME in the regular object. This is what we expect
1421 when we override a function in a shared object: that the
1422 references in the shared object will be mapped to the
1423 definition in the regular object. */
1425 while (hi->root.type == bfd_link_hash_indirect
1426 || hi->root.type == bfd_link_hash_warning)
1427 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1429 h->root.type = bfd_link_hash_indirect;
1430 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1431 if (h->def_dynamic)
1433 h->def_dynamic = 0;
1434 hi->ref_dynamic = 1;
1435 if (hi->ref_regular
1436 || hi->def_regular)
1438 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1439 return FALSE;
1443 /* Now set HI to H, so that the following code will set the
1444 other fields correctly. */
1445 hi = h;
1448 /* If there is a duplicate definition somewhere, then HI may not
1449 point to an indirect symbol. We will have reported an error to
1450 the user in that case. */
1452 if (hi->root.type == bfd_link_hash_indirect)
1454 struct elf_link_hash_entry *ht;
1456 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1457 (*bed->elf_backend_copy_indirect_symbol) (bed, ht, hi);
1459 /* See if the new flags lead us to realize that the symbol must
1460 be dynamic. */
1461 if (! *dynsym)
1463 if (! dynamic)
1465 if (info->shared
1466 || hi->ref_dynamic)
1467 *dynsym = TRUE;
1469 else
1471 if (hi->ref_regular)
1472 *dynsym = TRUE;
1477 /* We also need to define an indirection from the nondefault version
1478 of the symbol. */
1480 nondefault:
1481 len = strlen (name);
1482 shortname = bfd_hash_allocate (&info->hash->table, len);
1483 if (shortname == NULL)
1484 return FALSE;
1485 memcpy (shortname, name, shortlen);
1486 memcpy (shortname + shortlen, p + 1, len - shortlen);
1488 /* Once again, merge with any existing symbol. */
1489 type_change_ok = FALSE;
1490 size_change_ok = FALSE;
1491 sec = *psec;
1492 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1493 NULL, &hi, &skip, &override,
1494 &type_change_ok, &size_change_ok))
1495 return FALSE;
1497 if (skip)
1498 return TRUE;
1500 if (override)
1502 /* Here SHORTNAME is a versioned name, so we don't expect to see
1503 the type of override we do in the case above unless it is
1504 overridden by a versioned definition. */
1505 if (hi->root.type != bfd_link_hash_defined
1506 && hi->root.type != bfd_link_hash_defweak)
1507 (*_bfd_error_handler)
1508 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1509 abfd, shortname);
1511 else
1513 bh = &hi->root;
1514 if (! (_bfd_generic_link_add_one_symbol
1515 (info, abfd, shortname, BSF_INDIRECT,
1516 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1517 return FALSE;
1518 hi = (struct elf_link_hash_entry *) bh;
1520 /* If there is a duplicate definition somewhere, then HI may not
1521 point to an indirect symbol. We will have reported an error
1522 to the user in that case. */
1524 if (hi->root.type == bfd_link_hash_indirect)
1526 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
1528 /* See if the new flags lead us to realize that the symbol
1529 must be dynamic. */
1530 if (! *dynsym)
1532 if (! dynamic)
1534 if (info->shared
1535 || hi->ref_dynamic)
1536 *dynsym = TRUE;
1538 else
1540 if (hi->ref_regular)
1541 *dynsym = TRUE;
1547 return TRUE;
1550 /* This routine is used to export all defined symbols into the dynamic
1551 symbol table. It is called via elf_link_hash_traverse. */
1553 bfd_boolean
1554 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1556 struct elf_info_failed *eif = data;
1558 /* Ignore indirect symbols. These are added by the versioning code. */
1559 if (h->root.type == bfd_link_hash_indirect)
1560 return TRUE;
1562 if (h->root.type == bfd_link_hash_warning)
1563 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1565 if (h->dynindx == -1
1566 && (h->def_regular
1567 || h->ref_regular))
1569 struct bfd_elf_version_tree *t;
1570 struct bfd_elf_version_expr *d;
1572 for (t = eif->verdefs; t != NULL; t = t->next)
1574 if (t->globals.list != NULL)
1576 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1577 if (d != NULL)
1578 goto doit;
1581 if (t->locals.list != NULL)
1583 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1584 if (d != NULL)
1585 return TRUE;
1589 if (!eif->verdefs)
1591 doit:
1592 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1594 eif->failed = TRUE;
1595 return FALSE;
1600 return TRUE;
1603 /* Look through the symbols which are defined in other shared
1604 libraries and referenced here. Update the list of version
1605 dependencies. This will be put into the .gnu.version_r section.
1606 This function is called via elf_link_hash_traverse. */
1608 bfd_boolean
1609 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1610 void *data)
1612 struct elf_find_verdep_info *rinfo = data;
1613 Elf_Internal_Verneed *t;
1614 Elf_Internal_Vernaux *a;
1615 bfd_size_type amt;
1617 if (h->root.type == bfd_link_hash_warning)
1618 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1620 /* We only care about symbols defined in shared objects with version
1621 information. */
1622 if (!h->def_dynamic
1623 || h->def_regular
1624 || h->dynindx == -1
1625 || h->verinfo.verdef == NULL)
1626 return TRUE;
1628 /* See if we already know about this version. */
1629 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1631 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1632 continue;
1634 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1635 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1636 return TRUE;
1638 break;
1641 /* This is a new version. Add it to tree we are building. */
1643 if (t == NULL)
1645 amt = sizeof *t;
1646 t = bfd_zalloc (rinfo->output_bfd, amt);
1647 if (t == NULL)
1649 rinfo->failed = TRUE;
1650 return FALSE;
1653 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1654 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1655 elf_tdata (rinfo->output_bfd)->verref = t;
1658 amt = sizeof *a;
1659 a = bfd_zalloc (rinfo->output_bfd, amt);
1661 /* Note that we are copying a string pointer here, and testing it
1662 above. If bfd_elf_string_from_elf_section is ever changed to
1663 discard the string data when low in memory, this will have to be
1664 fixed. */
1665 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1667 a->vna_flags = h->verinfo.verdef->vd_flags;
1668 a->vna_nextptr = t->vn_auxptr;
1670 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1671 ++rinfo->vers;
1673 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1675 t->vn_auxptr = a;
1677 return TRUE;
1680 /* Figure out appropriate versions for all the symbols. We may not
1681 have the version number script until we have read all of the input
1682 files, so until that point we don't know which symbols should be
1683 local. This function is called via elf_link_hash_traverse. */
1685 bfd_boolean
1686 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1688 struct elf_assign_sym_version_info *sinfo;
1689 struct bfd_link_info *info;
1690 const struct elf_backend_data *bed;
1691 struct elf_info_failed eif;
1692 char *p;
1693 bfd_size_type amt;
1695 sinfo = data;
1696 info = sinfo->info;
1698 if (h->root.type == bfd_link_hash_warning)
1699 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1701 /* Fix the symbol flags. */
1702 eif.failed = FALSE;
1703 eif.info = info;
1704 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1706 if (eif.failed)
1707 sinfo->failed = TRUE;
1708 return FALSE;
1711 /* We only need version numbers for symbols defined in regular
1712 objects. */
1713 if (!h->def_regular)
1714 return TRUE;
1716 bed = get_elf_backend_data (sinfo->output_bfd);
1717 p = strchr (h->root.root.string, ELF_VER_CHR);
1718 if (p != NULL && h->verinfo.vertree == NULL)
1720 struct bfd_elf_version_tree *t;
1721 bfd_boolean hidden;
1723 hidden = TRUE;
1725 /* There are two consecutive ELF_VER_CHR characters if this is
1726 not a hidden symbol. */
1727 ++p;
1728 if (*p == ELF_VER_CHR)
1730 hidden = FALSE;
1731 ++p;
1734 /* If there is no version string, we can just return out. */
1735 if (*p == '\0')
1737 if (hidden)
1738 h->hidden = 1;
1739 return TRUE;
1742 /* Look for the version. If we find it, it is no longer weak. */
1743 for (t = sinfo->verdefs; t != NULL; t = t->next)
1745 if (strcmp (t->name, p) == 0)
1747 size_t len;
1748 char *alc;
1749 struct bfd_elf_version_expr *d;
1751 len = p - h->root.root.string;
1752 alc = bfd_malloc (len);
1753 if (alc == NULL)
1754 return FALSE;
1755 memcpy (alc, h->root.root.string, len - 1);
1756 alc[len - 1] = '\0';
1757 if (alc[len - 2] == ELF_VER_CHR)
1758 alc[len - 2] = '\0';
1760 h->verinfo.vertree = t;
1761 t->used = TRUE;
1762 d = NULL;
1764 if (t->globals.list != NULL)
1765 d = (*t->match) (&t->globals, NULL, alc);
1767 /* See if there is anything to force this symbol to
1768 local scope. */
1769 if (d == NULL && t->locals.list != NULL)
1771 d = (*t->match) (&t->locals, NULL, alc);
1772 if (d != NULL
1773 && h->dynindx != -1
1774 && info->shared
1775 && ! info->export_dynamic)
1776 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1779 free (alc);
1780 break;
1784 /* If we are building an application, we need to create a
1785 version node for this version. */
1786 if (t == NULL && info->executable)
1788 struct bfd_elf_version_tree **pp;
1789 int version_index;
1791 /* If we aren't going to export this symbol, we don't need
1792 to worry about it. */
1793 if (h->dynindx == -1)
1794 return TRUE;
1796 amt = sizeof *t;
1797 t = bfd_zalloc (sinfo->output_bfd, amt);
1798 if (t == NULL)
1800 sinfo->failed = TRUE;
1801 return FALSE;
1804 t->name = p;
1805 t->name_indx = (unsigned int) -1;
1806 t->used = TRUE;
1808 version_index = 1;
1809 /* Don't count anonymous version tag. */
1810 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1811 version_index = 0;
1812 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1813 ++version_index;
1814 t->vernum = version_index;
1816 *pp = t;
1818 h->verinfo.vertree = t;
1820 else if (t == NULL)
1822 /* We could not find the version for a symbol when
1823 generating a shared archive. Return an error. */
1824 (*_bfd_error_handler)
1825 (_("%B: undefined versioned symbol name %s"),
1826 sinfo->output_bfd, h->root.root.string);
1827 bfd_set_error (bfd_error_bad_value);
1828 sinfo->failed = TRUE;
1829 return FALSE;
1832 if (hidden)
1833 h->hidden = 1;
1836 /* If we don't have a version for this symbol, see if we can find
1837 something. */
1838 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1840 struct bfd_elf_version_tree *t;
1841 struct bfd_elf_version_tree *local_ver;
1842 struct bfd_elf_version_expr *d;
1844 /* See if can find what version this symbol is in. If the
1845 symbol is supposed to be local, then don't actually register
1846 it. */
1847 local_ver = NULL;
1848 for (t = sinfo->verdefs; t != NULL; t = t->next)
1850 if (t->globals.list != NULL)
1852 bfd_boolean matched;
1854 matched = FALSE;
1855 d = NULL;
1856 while ((d = (*t->match) (&t->globals, d,
1857 h->root.root.string)) != NULL)
1858 if (d->symver)
1859 matched = TRUE;
1860 else
1862 /* There is a version without definition. Make
1863 the symbol the default definition for this
1864 version. */
1865 h->verinfo.vertree = t;
1866 local_ver = NULL;
1867 d->script = 1;
1868 break;
1870 if (d != NULL)
1871 break;
1872 else if (matched)
1873 /* There is no undefined version for this symbol. Hide the
1874 default one. */
1875 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1878 if (t->locals.list != NULL)
1880 d = NULL;
1881 while ((d = (*t->match) (&t->locals, d,
1882 h->root.root.string)) != NULL)
1884 local_ver = t;
1885 /* If the match is "*", keep looking for a more
1886 explicit, perhaps even global, match.
1887 XXX: Shouldn't this be !d->wildcard instead? */
1888 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1889 break;
1892 if (d != NULL)
1893 break;
1897 if (local_ver != NULL)
1899 h->verinfo.vertree = local_ver;
1900 if (h->dynindx != -1
1901 && info->shared
1902 && ! info->export_dynamic)
1904 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1909 return TRUE;
1912 /* Read and swap the relocs from the section indicated by SHDR. This
1913 may be either a REL or a RELA section. The relocations are
1914 translated into RELA relocations and stored in INTERNAL_RELOCS,
1915 which should have already been allocated to contain enough space.
1916 The EXTERNAL_RELOCS are a buffer where the external form of the
1917 relocations should be stored.
1919 Returns FALSE if something goes wrong. */
1921 static bfd_boolean
1922 elf_link_read_relocs_from_section (bfd *abfd,
1923 asection *sec,
1924 Elf_Internal_Shdr *shdr,
1925 void *external_relocs,
1926 Elf_Internal_Rela *internal_relocs)
1928 const struct elf_backend_data *bed;
1929 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1930 const bfd_byte *erela;
1931 const bfd_byte *erelaend;
1932 Elf_Internal_Rela *irela;
1933 Elf_Internal_Shdr *symtab_hdr;
1934 size_t nsyms;
1936 /* Position ourselves at the start of the section. */
1937 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1938 return FALSE;
1940 /* Read the relocations. */
1941 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1942 return FALSE;
1944 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1945 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1947 bed = get_elf_backend_data (abfd);
1949 /* Convert the external relocations to the internal format. */
1950 if (shdr->sh_entsize == bed->s->sizeof_rel)
1951 swap_in = bed->s->swap_reloc_in;
1952 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1953 swap_in = bed->s->swap_reloca_in;
1954 else
1956 bfd_set_error (bfd_error_wrong_format);
1957 return FALSE;
1960 erela = external_relocs;
1961 erelaend = erela + shdr->sh_size;
1962 irela = internal_relocs;
1963 while (erela < erelaend)
1965 bfd_vma r_symndx;
1967 (*swap_in) (abfd, erela, irela);
1968 r_symndx = ELF32_R_SYM (irela->r_info);
1969 if (bed->s->arch_size == 64)
1970 r_symndx >>= 24;
1971 if ((size_t) r_symndx >= nsyms)
1973 (*_bfd_error_handler)
1974 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
1975 " for offset 0x%lx in section `%A'"),
1976 abfd, sec,
1977 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
1978 bfd_set_error (bfd_error_bad_value);
1979 return FALSE;
1981 irela += bed->s->int_rels_per_ext_rel;
1982 erela += shdr->sh_entsize;
1985 return TRUE;
1988 /* Read and swap the relocs for a section O. They may have been
1989 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
1990 not NULL, they are used as buffers to read into. They are known to
1991 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
1992 the return value is allocated using either malloc or bfd_alloc,
1993 according to the KEEP_MEMORY argument. If O has two relocation
1994 sections (both REL and RELA relocations), then the REL_HDR
1995 relocations will appear first in INTERNAL_RELOCS, followed by the
1996 REL_HDR2 relocations. */
1998 Elf_Internal_Rela *
1999 _bfd_elf_link_read_relocs (bfd *abfd,
2000 asection *o,
2001 void *external_relocs,
2002 Elf_Internal_Rela *internal_relocs,
2003 bfd_boolean keep_memory)
2005 Elf_Internal_Shdr *rel_hdr;
2006 void *alloc1 = NULL;
2007 Elf_Internal_Rela *alloc2 = NULL;
2008 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2010 if (elf_section_data (o)->relocs != NULL)
2011 return elf_section_data (o)->relocs;
2013 if (o->reloc_count == 0)
2014 return NULL;
2016 rel_hdr = &elf_section_data (o)->rel_hdr;
2018 if (internal_relocs == NULL)
2020 bfd_size_type size;
2022 size = o->reloc_count;
2023 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2024 if (keep_memory)
2025 internal_relocs = bfd_alloc (abfd, size);
2026 else
2027 internal_relocs = alloc2 = bfd_malloc (size);
2028 if (internal_relocs == NULL)
2029 goto error_return;
2032 if (external_relocs == NULL)
2034 bfd_size_type size = rel_hdr->sh_size;
2036 if (elf_section_data (o)->rel_hdr2)
2037 size += elf_section_data (o)->rel_hdr2->sh_size;
2038 alloc1 = bfd_malloc (size);
2039 if (alloc1 == NULL)
2040 goto error_return;
2041 external_relocs = alloc1;
2044 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2045 external_relocs,
2046 internal_relocs))
2047 goto error_return;
2048 if (elf_section_data (o)->rel_hdr2
2049 && (!elf_link_read_relocs_from_section
2050 (abfd, o,
2051 elf_section_data (o)->rel_hdr2,
2052 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2053 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2054 * bed->s->int_rels_per_ext_rel))))
2055 goto error_return;
2057 /* Cache the results for next time, if we can. */
2058 if (keep_memory)
2059 elf_section_data (o)->relocs = internal_relocs;
2061 if (alloc1 != NULL)
2062 free (alloc1);
2064 /* Don't free alloc2, since if it was allocated we are passing it
2065 back (under the name of internal_relocs). */
2067 return internal_relocs;
2069 error_return:
2070 if (alloc1 != NULL)
2071 free (alloc1);
2072 if (alloc2 != NULL)
2073 free (alloc2);
2074 return NULL;
2077 /* Compute the size of, and allocate space for, REL_HDR which is the
2078 section header for a section containing relocations for O. */
2080 bfd_boolean
2081 _bfd_elf_link_size_reloc_section (bfd *abfd,
2082 Elf_Internal_Shdr *rel_hdr,
2083 asection *o)
2085 bfd_size_type reloc_count;
2086 bfd_size_type num_rel_hashes;
2088 /* Figure out how many relocations there will be. */
2089 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2090 reloc_count = elf_section_data (o)->rel_count;
2091 else
2092 reloc_count = elf_section_data (o)->rel_count2;
2094 num_rel_hashes = o->reloc_count;
2095 if (num_rel_hashes < reloc_count)
2096 num_rel_hashes = reloc_count;
2098 /* That allows us to calculate the size of the section. */
2099 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2101 /* The contents field must last into write_object_contents, so we
2102 allocate it with bfd_alloc rather than malloc. Also since we
2103 cannot be sure that the contents will actually be filled in,
2104 we zero the allocated space. */
2105 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2106 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2107 return FALSE;
2109 /* We only allocate one set of hash entries, so we only do it the
2110 first time we are called. */
2111 if (elf_section_data (o)->rel_hashes == NULL
2112 && num_rel_hashes)
2114 struct elf_link_hash_entry **p;
2116 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2117 if (p == NULL)
2118 return FALSE;
2120 elf_section_data (o)->rel_hashes = p;
2123 return TRUE;
2126 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2127 originated from the section given by INPUT_REL_HDR) to the
2128 OUTPUT_BFD. */
2130 bfd_boolean
2131 _bfd_elf_link_output_relocs (bfd *output_bfd,
2132 asection *input_section,
2133 Elf_Internal_Shdr *input_rel_hdr,
2134 Elf_Internal_Rela *internal_relocs)
2136 Elf_Internal_Rela *irela;
2137 Elf_Internal_Rela *irelaend;
2138 bfd_byte *erel;
2139 Elf_Internal_Shdr *output_rel_hdr;
2140 asection *output_section;
2141 unsigned int *rel_countp = NULL;
2142 const struct elf_backend_data *bed;
2143 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2145 output_section = input_section->output_section;
2146 output_rel_hdr = NULL;
2148 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2149 == input_rel_hdr->sh_entsize)
2151 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2152 rel_countp = &elf_section_data (output_section)->rel_count;
2154 else if (elf_section_data (output_section)->rel_hdr2
2155 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2156 == input_rel_hdr->sh_entsize))
2158 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2159 rel_countp = &elf_section_data (output_section)->rel_count2;
2161 else
2163 (*_bfd_error_handler)
2164 (_("%B: relocation size mismatch in %B section %A"),
2165 output_bfd, input_section->owner, input_section);
2166 bfd_set_error (bfd_error_wrong_object_format);
2167 return FALSE;
2170 bed = get_elf_backend_data (output_bfd);
2171 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2172 swap_out = bed->s->swap_reloc_out;
2173 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2174 swap_out = bed->s->swap_reloca_out;
2175 else
2176 abort ();
2178 erel = output_rel_hdr->contents;
2179 erel += *rel_countp * input_rel_hdr->sh_entsize;
2180 irela = internal_relocs;
2181 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2182 * bed->s->int_rels_per_ext_rel);
2183 while (irela < irelaend)
2185 (*swap_out) (output_bfd, irela, erel);
2186 irela += bed->s->int_rels_per_ext_rel;
2187 erel += input_rel_hdr->sh_entsize;
2190 /* Bump the counter, so that we know where to add the next set of
2191 relocations. */
2192 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2194 return TRUE;
2197 /* Fix up the flags for a symbol. This handles various cases which
2198 can only be fixed after all the input files are seen. This is
2199 currently called by both adjust_dynamic_symbol and
2200 assign_sym_version, which is unnecessary but perhaps more robust in
2201 the face of future changes. */
2203 bfd_boolean
2204 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2205 struct elf_info_failed *eif)
2207 /* If this symbol was mentioned in a non-ELF file, try to set
2208 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2209 permit a non-ELF file to correctly refer to a symbol defined in
2210 an ELF dynamic object. */
2211 if (h->non_elf)
2213 while (h->root.type == bfd_link_hash_indirect)
2214 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2216 if (h->root.type != bfd_link_hash_defined
2217 && h->root.type != bfd_link_hash_defweak)
2219 h->ref_regular = 1;
2220 h->ref_regular_nonweak = 1;
2222 else
2224 if (h->root.u.def.section->owner != NULL
2225 && (bfd_get_flavour (h->root.u.def.section->owner)
2226 == bfd_target_elf_flavour))
2228 h->ref_regular = 1;
2229 h->ref_regular_nonweak = 1;
2231 else
2232 h->def_regular = 1;
2235 if (h->dynindx == -1
2236 && (h->def_dynamic
2237 || h->ref_dynamic))
2239 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2241 eif->failed = TRUE;
2242 return FALSE;
2246 else
2248 /* Unfortunately, NON_ELF is only correct if the symbol
2249 was first seen in a non-ELF file. Fortunately, if the symbol
2250 was first seen in an ELF file, we're probably OK unless the
2251 symbol was defined in a non-ELF file. Catch that case here.
2252 FIXME: We're still in trouble if the symbol was first seen in
2253 a dynamic object, and then later in a non-ELF regular object. */
2254 if ((h->root.type == bfd_link_hash_defined
2255 || h->root.type == bfd_link_hash_defweak)
2256 && !h->def_regular
2257 && (h->root.u.def.section->owner != NULL
2258 ? (bfd_get_flavour (h->root.u.def.section->owner)
2259 != bfd_target_elf_flavour)
2260 : (bfd_is_abs_section (h->root.u.def.section)
2261 && !h->def_dynamic)))
2262 h->def_regular = 1;
2265 /* If this is a final link, and the symbol was defined as a common
2266 symbol in a regular object file, and there was no definition in
2267 any dynamic object, then the linker will have allocated space for
2268 the symbol in a common section but the DEF_REGULAR
2269 flag will not have been set. */
2270 if (h->root.type == bfd_link_hash_defined
2271 && !h->def_regular
2272 && h->ref_regular
2273 && !h->def_dynamic
2274 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2275 h->def_regular = 1;
2277 /* If -Bsymbolic was used (which means to bind references to global
2278 symbols to the definition within the shared object), and this
2279 symbol was defined in a regular object, then it actually doesn't
2280 need a PLT entry. Likewise, if the symbol has non-default
2281 visibility. If the symbol has hidden or internal visibility, we
2282 will force it local. */
2283 if (h->needs_plt
2284 && eif->info->shared
2285 && is_elf_hash_table (eif->info->hash)
2286 && (eif->info->symbolic
2287 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2288 && h->def_regular)
2290 const struct elf_backend_data *bed;
2291 bfd_boolean force_local;
2293 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2295 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2296 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2297 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2300 /* If a weak undefined symbol has non-default visibility, we also
2301 hide it from the dynamic linker. */
2302 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2303 && h->root.type == bfd_link_hash_undefweak)
2305 const struct elf_backend_data *bed;
2306 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2307 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2310 /* If this is a weak defined symbol in a dynamic object, and we know
2311 the real definition in the dynamic object, copy interesting flags
2312 over to the real definition. */
2313 if (h->u.weakdef != NULL)
2315 struct elf_link_hash_entry *weakdef;
2317 weakdef = h->u.weakdef;
2318 if (h->root.type == bfd_link_hash_indirect)
2319 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2321 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2322 || h->root.type == bfd_link_hash_defweak);
2323 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2324 || weakdef->root.type == bfd_link_hash_defweak);
2325 BFD_ASSERT (weakdef->def_dynamic);
2327 /* If the real definition is defined by a regular object file,
2328 don't do anything special. See the longer description in
2329 _bfd_elf_adjust_dynamic_symbol, below. */
2330 if (weakdef->def_regular)
2331 h->u.weakdef = NULL;
2332 else
2334 const struct elf_backend_data *bed;
2336 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2337 (*bed->elf_backend_copy_indirect_symbol) (bed, weakdef, h);
2341 return TRUE;
2344 /* Make the backend pick a good value for a dynamic symbol. This is
2345 called via elf_link_hash_traverse, and also calls itself
2346 recursively. */
2348 bfd_boolean
2349 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2351 struct elf_info_failed *eif = data;
2352 bfd *dynobj;
2353 const struct elf_backend_data *bed;
2355 if (! is_elf_hash_table (eif->info->hash))
2356 return FALSE;
2358 if (h->root.type == bfd_link_hash_warning)
2360 h->plt = elf_hash_table (eif->info)->init_offset;
2361 h->got = elf_hash_table (eif->info)->init_offset;
2363 /* When warning symbols are created, they **replace** the "real"
2364 entry in the hash table, thus we never get to see the real
2365 symbol in a hash traversal. So look at it now. */
2366 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2369 /* Ignore indirect symbols. These are added by the versioning code. */
2370 if (h->root.type == bfd_link_hash_indirect)
2371 return TRUE;
2373 /* Fix the symbol flags. */
2374 if (! _bfd_elf_fix_symbol_flags (h, eif))
2375 return FALSE;
2377 /* If this symbol does not require a PLT entry, and it is not
2378 defined by a dynamic object, or is not referenced by a regular
2379 object, ignore it. We do have to handle a weak defined symbol,
2380 even if no regular object refers to it, if we decided to add it
2381 to the dynamic symbol table. FIXME: Do we normally need to worry
2382 about symbols which are defined by one dynamic object and
2383 referenced by another one? */
2384 if (!h->needs_plt
2385 && (h->def_regular
2386 || !h->def_dynamic
2387 || (!h->ref_regular
2388 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2390 h->plt = elf_hash_table (eif->info)->init_offset;
2391 return TRUE;
2394 /* If we've already adjusted this symbol, don't do it again. This
2395 can happen via a recursive call. */
2396 if (h->dynamic_adjusted)
2397 return TRUE;
2399 /* Don't look at this symbol again. Note that we must set this
2400 after checking the above conditions, because we may look at a
2401 symbol once, decide not to do anything, and then get called
2402 recursively later after REF_REGULAR is set below. */
2403 h->dynamic_adjusted = 1;
2405 /* If this is a weak definition, and we know a real definition, and
2406 the real symbol is not itself defined by a regular object file,
2407 then get a good value for the real definition. We handle the
2408 real symbol first, for the convenience of the backend routine.
2410 Note that there is a confusing case here. If the real definition
2411 is defined by a regular object file, we don't get the real symbol
2412 from the dynamic object, but we do get the weak symbol. If the
2413 processor backend uses a COPY reloc, then if some routine in the
2414 dynamic object changes the real symbol, we will not see that
2415 change in the corresponding weak symbol. This is the way other
2416 ELF linkers work as well, and seems to be a result of the shared
2417 library model.
2419 I will clarify this issue. Most SVR4 shared libraries define the
2420 variable _timezone and define timezone as a weak synonym. The
2421 tzset call changes _timezone. If you write
2422 extern int timezone;
2423 int _timezone = 5;
2424 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2425 you might expect that, since timezone is a synonym for _timezone,
2426 the same number will print both times. However, if the processor
2427 backend uses a COPY reloc, then actually timezone will be copied
2428 into your process image, and, since you define _timezone
2429 yourself, _timezone will not. Thus timezone and _timezone will
2430 wind up at different memory locations. The tzset call will set
2431 _timezone, leaving timezone unchanged. */
2433 if (h->u.weakdef != NULL)
2435 /* If we get to this point, we know there is an implicit
2436 reference by a regular object file via the weak symbol H.
2437 FIXME: Is this really true? What if the traversal finds
2438 H->U.WEAKDEF before it finds H? */
2439 h->u.weakdef->ref_regular = 1;
2441 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2442 return FALSE;
2445 /* If a symbol has no type and no size and does not require a PLT
2446 entry, then we are probably about to do the wrong thing here: we
2447 are probably going to create a COPY reloc for an empty object.
2448 This case can arise when a shared object is built with assembly
2449 code, and the assembly code fails to set the symbol type. */
2450 if (h->size == 0
2451 && h->type == STT_NOTYPE
2452 && !h->needs_plt)
2453 (*_bfd_error_handler)
2454 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2455 h->root.root.string);
2457 dynobj = elf_hash_table (eif->info)->dynobj;
2458 bed = get_elf_backend_data (dynobj);
2459 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2461 eif->failed = TRUE;
2462 return FALSE;
2465 return TRUE;
2468 /* Adjust all external symbols pointing into SEC_MERGE sections
2469 to reflect the object merging within the sections. */
2471 bfd_boolean
2472 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2474 asection *sec;
2476 if (h->root.type == bfd_link_hash_warning)
2477 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2479 if ((h->root.type == bfd_link_hash_defined
2480 || h->root.type == bfd_link_hash_defweak)
2481 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2482 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2484 bfd *output_bfd = data;
2486 h->root.u.def.value =
2487 _bfd_merged_section_offset (output_bfd,
2488 &h->root.u.def.section,
2489 elf_section_data (sec)->sec_info,
2490 h->root.u.def.value);
2493 return TRUE;
2496 /* Returns false if the symbol referred to by H should be considered
2497 to resolve local to the current module, and true if it should be
2498 considered to bind dynamically. */
2500 bfd_boolean
2501 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2502 struct bfd_link_info *info,
2503 bfd_boolean ignore_protected)
2505 bfd_boolean binding_stays_local_p;
2507 if (h == NULL)
2508 return FALSE;
2510 while (h->root.type == bfd_link_hash_indirect
2511 || h->root.type == bfd_link_hash_warning)
2512 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2514 /* If it was forced local, then clearly it's not dynamic. */
2515 if (h->dynindx == -1)
2516 return FALSE;
2517 if (h->forced_local)
2518 return FALSE;
2520 /* Identify the cases where name binding rules say that a
2521 visible symbol resolves locally. */
2522 binding_stays_local_p = info->executable || info->symbolic;
2524 switch (ELF_ST_VISIBILITY (h->other))
2526 case STV_INTERNAL:
2527 case STV_HIDDEN:
2528 return FALSE;
2530 case STV_PROTECTED:
2531 /* Proper resolution for function pointer equality may require
2532 that these symbols perhaps be resolved dynamically, even though
2533 we should be resolving them to the current module. */
2534 if (!ignore_protected || h->type != STT_FUNC)
2535 binding_stays_local_p = TRUE;
2536 break;
2538 default:
2539 break;
2542 /* If it isn't defined locally, then clearly it's dynamic. */
2543 if (!h->def_regular)
2544 return TRUE;
2546 /* Otherwise, the symbol is dynamic if binding rules don't tell
2547 us that it remains local. */
2548 return !binding_stays_local_p;
2551 /* Return true if the symbol referred to by H should be considered
2552 to resolve local to the current module, and false otherwise. Differs
2553 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2554 undefined symbols and weak symbols. */
2556 bfd_boolean
2557 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2558 struct bfd_link_info *info,
2559 bfd_boolean local_protected)
2561 /* If it's a local sym, of course we resolve locally. */
2562 if (h == NULL)
2563 return TRUE;
2565 /* Common symbols that become definitions don't get the DEF_REGULAR
2566 flag set, so test it first, and don't bail out. */
2567 if (ELF_COMMON_DEF_P (h))
2568 /* Do nothing. */;
2569 /* If we don't have a definition in a regular file, then we can't
2570 resolve locally. The sym is either undefined or dynamic. */
2571 else if (!h->def_regular)
2572 return FALSE;
2574 /* Forced local symbols resolve locally. */
2575 if (h->forced_local)
2576 return TRUE;
2578 /* As do non-dynamic symbols. */
2579 if (h->dynindx == -1)
2580 return TRUE;
2582 /* At this point, we know the symbol is defined and dynamic. In an
2583 executable it must resolve locally, likewise when building symbolic
2584 shared libraries. */
2585 if (info->executable || info->symbolic)
2586 return TRUE;
2588 /* Now deal with defined dynamic symbols in shared libraries. Ones
2589 with default visibility might not resolve locally. */
2590 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2591 return FALSE;
2593 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2594 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2595 return TRUE;
2597 /* STV_PROTECTED non-function symbols are local. */
2598 if (h->type != STT_FUNC)
2599 return TRUE;
2601 /* Function pointer equality tests may require that STV_PROTECTED
2602 symbols be treated as dynamic symbols, even when we know that the
2603 dynamic linker will resolve them locally. */
2604 return local_protected;
2607 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2608 aligned. Returns the first TLS output section. */
2610 struct bfd_section *
2611 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2613 struct bfd_section *sec, *tls;
2614 unsigned int align = 0;
2616 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2617 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2618 break;
2619 tls = sec;
2621 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2622 if (sec->alignment_power > align)
2623 align = sec->alignment_power;
2625 elf_hash_table (info)->tls_sec = tls;
2627 /* Ensure the alignment of the first section is the largest alignment,
2628 so that the tls segment starts aligned. */
2629 if (tls != NULL)
2630 tls->alignment_power = align;
2632 return tls;
2635 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2636 static bfd_boolean
2637 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2638 Elf_Internal_Sym *sym)
2640 /* Local symbols do not count, but target specific ones might. */
2641 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2642 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2643 return FALSE;
2645 /* Function symbols do not count. */
2646 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2647 return FALSE;
2649 /* If the section is undefined, then so is the symbol. */
2650 if (sym->st_shndx == SHN_UNDEF)
2651 return FALSE;
2653 /* If the symbol is defined in the common section, then
2654 it is a common definition and so does not count. */
2655 if (sym->st_shndx == SHN_COMMON)
2656 return FALSE;
2658 /* If the symbol is in a target specific section then we
2659 must rely upon the backend to tell us what it is. */
2660 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2661 /* FIXME - this function is not coded yet:
2663 return _bfd_is_global_symbol_definition (abfd, sym);
2665 Instead for now assume that the definition is not global,
2666 Even if this is wrong, at least the linker will behave
2667 in the same way that it used to do. */
2668 return FALSE;
2670 return TRUE;
2673 /* Search the symbol table of the archive element of the archive ABFD
2674 whose archive map contains a mention of SYMDEF, and determine if
2675 the symbol is defined in this element. */
2676 static bfd_boolean
2677 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2679 Elf_Internal_Shdr * hdr;
2680 bfd_size_type symcount;
2681 bfd_size_type extsymcount;
2682 bfd_size_type extsymoff;
2683 Elf_Internal_Sym *isymbuf;
2684 Elf_Internal_Sym *isym;
2685 Elf_Internal_Sym *isymend;
2686 bfd_boolean result;
2688 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2689 if (abfd == NULL)
2690 return FALSE;
2692 if (! bfd_check_format (abfd, bfd_object))
2693 return FALSE;
2695 /* If we have already included the element containing this symbol in the
2696 link then we do not need to include it again. Just claim that any symbol
2697 it contains is not a definition, so that our caller will not decide to
2698 (re)include this element. */
2699 if (abfd->archive_pass)
2700 return FALSE;
2702 /* Select the appropriate symbol table. */
2703 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2704 hdr = &elf_tdata (abfd)->symtab_hdr;
2705 else
2706 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2708 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2710 /* The sh_info field of the symtab header tells us where the
2711 external symbols start. We don't care about the local symbols. */
2712 if (elf_bad_symtab (abfd))
2714 extsymcount = symcount;
2715 extsymoff = 0;
2717 else
2719 extsymcount = symcount - hdr->sh_info;
2720 extsymoff = hdr->sh_info;
2723 if (extsymcount == 0)
2724 return FALSE;
2726 /* Read in the symbol table. */
2727 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2728 NULL, NULL, NULL);
2729 if (isymbuf == NULL)
2730 return FALSE;
2732 /* Scan the symbol table looking for SYMDEF. */
2733 result = FALSE;
2734 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2736 const char *name;
2738 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2739 isym->st_name);
2740 if (name == NULL)
2741 break;
2743 if (strcmp (name, symdef->name) == 0)
2745 result = is_global_data_symbol_definition (abfd, isym);
2746 break;
2750 free (isymbuf);
2752 return result;
2755 /* Add an entry to the .dynamic table. */
2757 bfd_boolean
2758 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2759 bfd_vma tag,
2760 bfd_vma val)
2762 struct elf_link_hash_table *hash_table;
2763 const struct elf_backend_data *bed;
2764 asection *s;
2765 bfd_size_type newsize;
2766 bfd_byte *newcontents;
2767 Elf_Internal_Dyn dyn;
2769 hash_table = elf_hash_table (info);
2770 if (! is_elf_hash_table (hash_table))
2771 return FALSE;
2773 if (info->warn_shared_textrel && info->shared && tag == DT_TEXTREL)
2774 _bfd_error_handler
2775 (_("warning: creating a DT_TEXTREL in a shared object."));
2777 bed = get_elf_backend_data (hash_table->dynobj);
2778 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2779 BFD_ASSERT (s != NULL);
2781 newsize = s->size + bed->s->sizeof_dyn;
2782 newcontents = bfd_realloc (s->contents, newsize);
2783 if (newcontents == NULL)
2784 return FALSE;
2786 dyn.d_tag = tag;
2787 dyn.d_un.d_val = val;
2788 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2790 s->size = newsize;
2791 s->contents = newcontents;
2793 return TRUE;
2796 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2797 otherwise just check whether one already exists. Returns -1 on error,
2798 1 if a DT_NEEDED tag already exists, and 0 on success. */
2800 static int
2801 elf_add_dt_needed_tag (bfd *abfd,
2802 struct bfd_link_info *info,
2803 const char *soname,
2804 bfd_boolean do_it)
2806 struct elf_link_hash_table *hash_table;
2807 bfd_size_type oldsize;
2808 bfd_size_type strindex;
2810 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2811 return -1;
2813 hash_table = elf_hash_table (info);
2814 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2815 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2816 if (strindex == (bfd_size_type) -1)
2817 return -1;
2819 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2821 asection *sdyn;
2822 const struct elf_backend_data *bed;
2823 bfd_byte *extdyn;
2825 bed = get_elf_backend_data (hash_table->dynobj);
2826 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2827 if (sdyn != NULL)
2828 for (extdyn = sdyn->contents;
2829 extdyn < sdyn->contents + sdyn->size;
2830 extdyn += bed->s->sizeof_dyn)
2832 Elf_Internal_Dyn dyn;
2834 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2835 if (dyn.d_tag == DT_NEEDED
2836 && dyn.d_un.d_val == strindex)
2838 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2839 return 1;
2844 if (do_it)
2846 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2847 return -1;
2849 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2850 return -1;
2852 else
2853 /* We were just checking for existence of the tag. */
2854 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2856 return 0;
2859 /* Called via elf_link_hash_traverse, elf_smash_syms sets all symbols
2860 belonging to NOT_NEEDED to bfd_link_hash_new. We know there are no
2861 references from regular objects to these symbols.
2863 ??? Should we do something about references from other dynamic
2864 obects? If not, we potentially lose some warnings about undefined
2865 symbols. But how can we recover the initial undefined / undefweak
2866 state? */
2868 struct elf_smash_syms_data
2870 bfd *not_needed;
2871 struct elf_link_hash_table *htab;
2872 bfd_boolean twiddled;
2875 static bfd_boolean
2876 elf_smash_syms (struct elf_link_hash_entry *h, void *data)
2878 struct elf_smash_syms_data *inf = (struct elf_smash_syms_data *) data;
2879 struct bfd_link_hash_entry *bh;
2881 switch (h->root.type)
2883 default:
2884 case bfd_link_hash_new:
2885 return TRUE;
2887 case bfd_link_hash_undefined:
2888 if (h->root.u.undef.abfd != inf->not_needed)
2889 return TRUE;
2890 if (h->root.u.undef.weak != NULL
2891 && h->root.u.undef.weak != inf->not_needed)
2893 /* Symbol was undefweak in u.undef.weak bfd, and has become
2894 undefined in as-needed lib. Restore weak. */
2895 h->root.type = bfd_link_hash_undefweak;
2896 h->root.u.undef.abfd = h->root.u.undef.weak;
2897 if (h->root.u.undef.next != NULL
2898 || inf->htab->root.undefs_tail == &h->root)
2899 inf->twiddled = TRUE;
2900 return TRUE;
2902 break;
2904 case bfd_link_hash_undefweak:
2905 if (h->root.u.undef.abfd != inf->not_needed)
2906 return TRUE;
2907 break;
2909 case bfd_link_hash_defined:
2910 case bfd_link_hash_defweak:
2911 if (h->root.u.def.section->owner != inf->not_needed)
2912 return TRUE;
2913 break;
2915 case bfd_link_hash_common:
2916 if (h->root.u.c.p->section->owner != inf->not_needed)
2917 return TRUE;
2918 break;
2920 case bfd_link_hash_warning:
2921 case bfd_link_hash_indirect:
2922 elf_smash_syms ((struct elf_link_hash_entry *) h->root.u.i.link, data);
2923 if (h->root.u.i.link->type != bfd_link_hash_new)
2924 return TRUE;
2925 if (h->root.u.i.link->u.undef.abfd != inf->not_needed)
2926 return TRUE;
2927 break;
2930 /* There is no way we can undo symbol table state from defined or
2931 defweak back to undefined. */
2932 if (h->ref_regular)
2933 abort ();
2935 /* Set sym back to newly created state, but keep undefs list pointer. */
2936 bh = h->root.u.undef.next;
2937 if (bh != NULL || inf->htab->root.undefs_tail == &h->root)
2938 inf->twiddled = TRUE;
2939 (*inf->htab->root.table.newfunc) (&h->root.root,
2940 &inf->htab->root.table,
2941 h->root.root.string);
2942 h->root.u.undef.next = bh;
2943 h->root.u.undef.abfd = inf->not_needed;
2944 h->non_elf = 0;
2945 return TRUE;
2948 /* Sort symbol by value and section. */
2949 static int
2950 elf_sort_symbol (const void *arg1, const void *arg2)
2952 const struct elf_link_hash_entry *h1;
2953 const struct elf_link_hash_entry *h2;
2954 bfd_signed_vma vdiff;
2956 h1 = *(const struct elf_link_hash_entry **) arg1;
2957 h2 = *(const struct elf_link_hash_entry **) arg2;
2958 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2959 if (vdiff != 0)
2960 return vdiff > 0 ? 1 : -1;
2961 else
2963 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2964 if (sdiff != 0)
2965 return sdiff > 0 ? 1 : -1;
2967 return 0;
2970 /* This function is used to adjust offsets into .dynstr for
2971 dynamic symbols. This is called via elf_link_hash_traverse. */
2973 static bfd_boolean
2974 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
2976 struct elf_strtab_hash *dynstr = data;
2978 if (h->root.type == bfd_link_hash_warning)
2979 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2981 if (h->dynindx != -1)
2982 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
2983 return TRUE;
2986 /* Assign string offsets in .dynstr, update all structures referencing
2987 them. */
2989 static bfd_boolean
2990 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
2992 struct elf_link_hash_table *hash_table = elf_hash_table (info);
2993 struct elf_link_local_dynamic_entry *entry;
2994 struct elf_strtab_hash *dynstr = hash_table->dynstr;
2995 bfd *dynobj = hash_table->dynobj;
2996 asection *sdyn;
2997 bfd_size_type size;
2998 const struct elf_backend_data *bed;
2999 bfd_byte *extdyn;
3001 _bfd_elf_strtab_finalize (dynstr);
3002 size = _bfd_elf_strtab_size (dynstr);
3004 bed = get_elf_backend_data (dynobj);
3005 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3006 BFD_ASSERT (sdyn != NULL);
3008 /* Update all .dynamic entries referencing .dynstr strings. */
3009 for (extdyn = sdyn->contents;
3010 extdyn < sdyn->contents + sdyn->size;
3011 extdyn += bed->s->sizeof_dyn)
3013 Elf_Internal_Dyn dyn;
3015 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3016 switch (dyn.d_tag)
3018 case DT_STRSZ:
3019 dyn.d_un.d_val = size;
3020 break;
3021 case DT_NEEDED:
3022 case DT_SONAME:
3023 case DT_RPATH:
3024 case DT_RUNPATH:
3025 case DT_FILTER:
3026 case DT_AUXILIARY:
3027 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3028 break;
3029 default:
3030 continue;
3032 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3035 /* Now update local dynamic symbols. */
3036 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3037 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3038 entry->isym.st_name);
3040 /* And the rest of dynamic symbols. */
3041 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3043 /* Adjust version definitions. */
3044 if (elf_tdata (output_bfd)->cverdefs)
3046 asection *s;
3047 bfd_byte *p;
3048 bfd_size_type i;
3049 Elf_Internal_Verdef def;
3050 Elf_Internal_Verdaux defaux;
3052 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3053 p = s->contents;
3056 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3057 &def);
3058 p += sizeof (Elf_External_Verdef);
3059 if (def.vd_aux != sizeof (Elf_External_Verdef))
3060 continue;
3061 for (i = 0; i < def.vd_cnt; ++i)
3063 _bfd_elf_swap_verdaux_in (output_bfd,
3064 (Elf_External_Verdaux *) p, &defaux);
3065 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3066 defaux.vda_name);
3067 _bfd_elf_swap_verdaux_out (output_bfd,
3068 &defaux, (Elf_External_Verdaux *) p);
3069 p += sizeof (Elf_External_Verdaux);
3072 while (def.vd_next);
3075 /* Adjust version references. */
3076 if (elf_tdata (output_bfd)->verref)
3078 asection *s;
3079 bfd_byte *p;
3080 bfd_size_type i;
3081 Elf_Internal_Verneed need;
3082 Elf_Internal_Vernaux needaux;
3084 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3085 p = s->contents;
3088 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3089 &need);
3090 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3091 _bfd_elf_swap_verneed_out (output_bfd, &need,
3092 (Elf_External_Verneed *) p);
3093 p += sizeof (Elf_External_Verneed);
3094 for (i = 0; i < need.vn_cnt; ++i)
3096 _bfd_elf_swap_vernaux_in (output_bfd,
3097 (Elf_External_Vernaux *) p, &needaux);
3098 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3099 needaux.vna_name);
3100 _bfd_elf_swap_vernaux_out (output_bfd,
3101 &needaux,
3102 (Elf_External_Vernaux *) p);
3103 p += sizeof (Elf_External_Vernaux);
3106 while (need.vn_next);
3109 return TRUE;
3112 /* Add symbols from an ELF object file to the linker hash table. */
3114 static bfd_boolean
3115 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3117 bfd_boolean (*add_symbol_hook)
3118 (bfd *, struct bfd_link_info *, Elf_Internal_Sym *,
3119 const char **, flagword *, asection **, bfd_vma *);
3120 bfd_boolean (*check_relocs)
3121 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
3122 bfd_boolean (*check_directives)
3123 (bfd *, struct bfd_link_info *);
3124 bfd_boolean collect;
3125 Elf_Internal_Shdr *hdr;
3126 bfd_size_type symcount;
3127 bfd_size_type extsymcount;
3128 bfd_size_type extsymoff;
3129 struct elf_link_hash_entry **sym_hash;
3130 bfd_boolean dynamic;
3131 Elf_External_Versym *extversym = NULL;
3132 Elf_External_Versym *ever;
3133 struct elf_link_hash_entry *weaks;
3134 struct elf_link_hash_entry **nondeflt_vers = NULL;
3135 bfd_size_type nondeflt_vers_cnt = 0;
3136 Elf_Internal_Sym *isymbuf = NULL;
3137 Elf_Internal_Sym *isym;
3138 Elf_Internal_Sym *isymend;
3139 const struct elf_backend_data *bed;
3140 bfd_boolean add_needed;
3141 struct elf_link_hash_table * hash_table;
3142 bfd_size_type amt;
3144 hash_table = elf_hash_table (info);
3146 bed = get_elf_backend_data (abfd);
3147 add_symbol_hook = bed->elf_add_symbol_hook;
3148 collect = bed->collect;
3150 if ((abfd->flags & DYNAMIC) == 0)
3151 dynamic = FALSE;
3152 else
3154 dynamic = TRUE;
3156 /* You can't use -r against a dynamic object. Also, there's no
3157 hope of using a dynamic object which does not exactly match
3158 the format of the output file. */
3159 if (info->relocatable
3160 || !is_elf_hash_table (hash_table)
3161 || hash_table->root.creator != abfd->xvec)
3163 if (info->relocatable)
3164 bfd_set_error (bfd_error_invalid_operation);
3165 else
3166 bfd_set_error (bfd_error_wrong_format);
3167 goto error_return;
3171 /* As a GNU extension, any input sections which are named
3172 .gnu.warning.SYMBOL are treated as warning symbols for the given
3173 symbol. This differs from .gnu.warning sections, which generate
3174 warnings when they are included in an output file. */
3175 if (info->executable)
3177 asection *s;
3179 for (s = abfd->sections; s != NULL; s = s->next)
3181 const char *name;
3183 name = bfd_get_section_name (abfd, s);
3184 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
3186 char *msg;
3187 bfd_size_type sz;
3189 name += sizeof ".gnu.warning." - 1;
3191 /* If this is a shared object, then look up the symbol
3192 in the hash table. If it is there, and it is already
3193 been defined, then we will not be using the entry
3194 from this shared object, so we don't need to warn.
3195 FIXME: If we see the definition in a regular object
3196 later on, we will warn, but we shouldn't. The only
3197 fix is to keep track of what warnings we are supposed
3198 to emit, and then handle them all at the end of the
3199 link. */
3200 if (dynamic)
3202 struct elf_link_hash_entry *h;
3204 h = elf_link_hash_lookup (hash_table, name,
3205 FALSE, FALSE, TRUE);
3207 /* FIXME: What about bfd_link_hash_common? */
3208 if (h != NULL
3209 && (h->root.type == bfd_link_hash_defined
3210 || h->root.type == bfd_link_hash_defweak))
3212 /* We don't want to issue this warning. Clobber
3213 the section size so that the warning does not
3214 get copied into the output file. */
3215 s->size = 0;
3216 continue;
3220 sz = s->size;
3221 msg = bfd_alloc (abfd, sz + 1);
3222 if (msg == NULL)
3223 goto error_return;
3225 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3226 goto error_return;
3228 msg[sz] = '\0';
3230 if (! (_bfd_generic_link_add_one_symbol
3231 (info, abfd, name, BSF_WARNING, s, 0, msg,
3232 FALSE, collect, NULL)))
3233 goto error_return;
3235 if (! info->relocatable)
3237 /* Clobber the section size so that the warning does
3238 not get copied into the output file. */
3239 s->size = 0;
3245 add_needed = TRUE;
3246 if (! dynamic)
3248 /* If we are creating a shared library, create all the dynamic
3249 sections immediately. We need to attach them to something,
3250 so we attach them to this BFD, provided it is the right
3251 format. FIXME: If there are no input BFD's of the same
3252 format as the output, we can't make a shared library. */
3253 if (info->shared
3254 && is_elf_hash_table (hash_table)
3255 && hash_table->root.creator == abfd->xvec
3256 && ! hash_table->dynamic_sections_created)
3258 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3259 goto error_return;
3262 else if (!is_elf_hash_table (hash_table))
3263 goto error_return;
3264 else
3266 asection *s;
3267 const char *soname = NULL;
3268 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3269 int ret;
3271 /* ld --just-symbols and dynamic objects don't mix very well.
3272 Test for --just-symbols by looking at info set up by
3273 _bfd_elf_link_just_syms. */
3274 if ((s = abfd->sections) != NULL
3275 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3276 goto error_return;
3278 /* If this dynamic lib was specified on the command line with
3279 --as-needed in effect, then we don't want to add a DT_NEEDED
3280 tag unless the lib is actually used. Similary for libs brought
3281 in by another lib's DT_NEEDED. When --no-add-needed is used
3282 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3283 any dynamic library in DT_NEEDED tags in the dynamic lib at
3284 all. */
3285 add_needed = (elf_dyn_lib_class (abfd)
3286 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3287 | DYN_NO_NEEDED)) == 0;
3289 s = bfd_get_section_by_name (abfd, ".dynamic");
3290 if (s != NULL)
3292 bfd_byte *dynbuf;
3293 bfd_byte *extdyn;
3294 int elfsec;
3295 unsigned long shlink;
3297 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3298 goto error_free_dyn;
3300 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3301 if (elfsec == -1)
3302 goto error_free_dyn;
3303 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3305 for (extdyn = dynbuf;
3306 extdyn < dynbuf + s->size;
3307 extdyn += bed->s->sizeof_dyn)
3309 Elf_Internal_Dyn dyn;
3311 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3312 if (dyn.d_tag == DT_SONAME)
3314 unsigned int tagv = dyn.d_un.d_val;
3315 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3316 if (soname == NULL)
3317 goto error_free_dyn;
3319 if (dyn.d_tag == DT_NEEDED)
3321 struct bfd_link_needed_list *n, **pn;
3322 char *fnm, *anm;
3323 unsigned int tagv = dyn.d_un.d_val;
3325 amt = sizeof (struct bfd_link_needed_list);
3326 n = bfd_alloc (abfd, amt);
3327 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3328 if (n == NULL || fnm == NULL)
3329 goto error_free_dyn;
3330 amt = strlen (fnm) + 1;
3331 anm = bfd_alloc (abfd, amt);
3332 if (anm == NULL)
3333 goto error_free_dyn;
3334 memcpy (anm, fnm, amt);
3335 n->name = anm;
3336 n->by = abfd;
3337 n->next = NULL;
3338 for (pn = & hash_table->needed;
3339 *pn != NULL;
3340 pn = &(*pn)->next)
3342 *pn = n;
3344 if (dyn.d_tag == DT_RUNPATH)
3346 struct bfd_link_needed_list *n, **pn;
3347 char *fnm, *anm;
3348 unsigned int tagv = dyn.d_un.d_val;
3350 amt = sizeof (struct bfd_link_needed_list);
3351 n = bfd_alloc (abfd, amt);
3352 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3353 if (n == NULL || fnm == NULL)
3354 goto error_free_dyn;
3355 amt = strlen (fnm) + 1;
3356 anm = bfd_alloc (abfd, amt);
3357 if (anm == NULL)
3358 goto error_free_dyn;
3359 memcpy (anm, fnm, amt);
3360 n->name = anm;
3361 n->by = abfd;
3362 n->next = NULL;
3363 for (pn = & runpath;
3364 *pn != NULL;
3365 pn = &(*pn)->next)
3367 *pn = n;
3369 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3370 if (!runpath && dyn.d_tag == DT_RPATH)
3372 struct bfd_link_needed_list *n, **pn;
3373 char *fnm, *anm;
3374 unsigned int tagv = dyn.d_un.d_val;
3376 amt = sizeof (struct bfd_link_needed_list);
3377 n = bfd_alloc (abfd, amt);
3378 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3379 if (n == NULL || fnm == NULL)
3380 goto error_free_dyn;
3381 amt = strlen (fnm) + 1;
3382 anm = bfd_alloc (abfd, amt);
3383 if (anm == NULL)
3385 error_free_dyn:
3386 free (dynbuf);
3387 goto error_return;
3389 memcpy (anm, fnm, amt);
3390 n->name = anm;
3391 n->by = abfd;
3392 n->next = NULL;
3393 for (pn = & rpath;
3394 *pn != NULL;
3395 pn = &(*pn)->next)
3397 *pn = n;
3401 free (dynbuf);
3404 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3405 frees all more recently bfd_alloc'd blocks as well. */
3406 if (runpath)
3407 rpath = runpath;
3409 if (rpath)
3411 struct bfd_link_needed_list **pn;
3412 for (pn = & hash_table->runpath;
3413 *pn != NULL;
3414 pn = &(*pn)->next)
3416 *pn = rpath;
3419 /* We do not want to include any of the sections in a dynamic
3420 object in the output file. We hack by simply clobbering the
3421 list of sections in the BFD. This could be handled more
3422 cleanly by, say, a new section flag; the existing
3423 SEC_NEVER_LOAD flag is not the one we want, because that one
3424 still implies that the section takes up space in the output
3425 file. */
3426 bfd_section_list_clear (abfd);
3428 /* Find the name to use in a DT_NEEDED entry that refers to this
3429 object. If the object has a DT_SONAME entry, we use it.
3430 Otherwise, if the generic linker stuck something in
3431 elf_dt_name, we use that. Otherwise, we just use the file
3432 name. */
3433 if (soname == NULL || *soname == '\0')
3435 soname = elf_dt_name (abfd);
3436 if (soname == NULL || *soname == '\0')
3437 soname = bfd_get_filename (abfd);
3440 /* Save the SONAME because sometimes the linker emulation code
3441 will need to know it. */
3442 elf_dt_name (abfd) = soname;
3444 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3445 if (ret < 0)
3446 goto error_return;
3448 /* If we have already included this dynamic object in the
3449 link, just ignore it. There is no reason to include a
3450 particular dynamic object more than once. */
3451 if (ret > 0)
3452 return TRUE;
3455 /* If this is a dynamic object, we always link against the .dynsym
3456 symbol table, not the .symtab symbol table. The dynamic linker
3457 will only see the .dynsym symbol table, so there is no reason to
3458 look at .symtab for a dynamic object. */
3460 if (! dynamic || elf_dynsymtab (abfd) == 0)
3461 hdr = &elf_tdata (abfd)->symtab_hdr;
3462 else
3463 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3465 symcount = hdr->sh_size / bed->s->sizeof_sym;
3467 /* The sh_info field of the symtab header tells us where the
3468 external symbols start. We don't care about the local symbols at
3469 this point. */
3470 if (elf_bad_symtab (abfd))
3472 extsymcount = symcount;
3473 extsymoff = 0;
3475 else
3477 extsymcount = symcount - hdr->sh_info;
3478 extsymoff = hdr->sh_info;
3481 sym_hash = NULL;
3482 if (extsymcount != 0)
3484 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3485 NULL, NULL, NULL);
3486 if (isymbuf == NULL)
3487 goto error_return;
3489 /* We store a pointer to the hash table entry for each external
3490 symbol. */
3491 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3492 sym_hash = bfd_alloc (abfd, amt);
3493 if (sym_hash == NULL)
3494 goto error_free_sym;
3495 elf_sym_hashes (abfd) = sym_hash;
3498 if (dynamic)
3500 /* Read in any version definitions. */
3501 if (!_bfd_elf_slurp_version_tables (abfd,
3502 info->default_imported_symver))
3503 goto error_free_sym;
3505 /* Read in the symbol versions, but don't bother to convert them
3506 to internal format. */
3507 if (elf_dynversym (abfd) != 0)
3509 Elf_Internal_Shdr *versymhdr;
3511 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3512 extversym = bfd_malloc (versymhdr->sh_size);
3513 if (extversym == NULL)
3514 goto error_free_sym;
3515 amt = versymhdr->sh_size;
3516 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3517 || bfd_bread (extversym, amt, abfd) != amt)
3518 goto error_free_vers;
3522 weaks = NULL;
3524 ever = extversym != NULL ? extversym + extsymoff : NULL;
3525 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3526 isym < isymend;
3527 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3529 int bind;
3530 bfd_vma value;
3531 asection *sec, *new_sec;
3532 flagword flags;
3533 const char *name;
3534 struct elf_link_hash_entry *h;
3535 bfd_boolean definition;
3536 bfd_boolean size_change_ok;
3537 bfd_boolean type_change_ok;
3538 bfd_boolean new_weakdef;
3539 bfd_boolean override;
3540 unsigned int old_alignment;
3541 bfd *old_bfd;
3543 override = FALSE;
3545 flags = BSF_NO_FLAGS;
3546 sec = NULL;
3547 value = isym->st_value;
3548 *sym_hash = NULL;
3550 bind = ELF_ST_BIND (isym->st_info);
3551 if (bind == STB_LOCAL)
3553 /* This should be impossible, since ELF requires that all
3554 global symbols follow all local symbols, and that sh_info
3555 point to the first global symbol. Unfortunately, Irix 5
3556 screws this up. */
3557 continue;
3559 else if (bind == STB_GLOBAL)
3561 if (isym->st_shndx != SHN_UNDEF
3562 && isym->st_shndx != SHN_COMMON)
3563 flags = BSF_GLOBAL;
3565 else if (bind == STB_WEAK)
3566 flags = BSF_WEAK;
3567 else
3569 /* Leave it up to the processor backend. */
3572 if (isym->st_shndx == SHN_UNDEF)
3573 sec = bfd_und_section_ptr;
3574 else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
3576 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3577 if (sec == NULL)
3578 sec = bfd_abs_section_ptr;
3579 else if (sec->kept_section)
3581 /* Symbols from discarded section are undefined, and have
3582 default visibility. */
3583 sec = bfd_und_section_ptr;
3584 isym->st_shndx = SHN_UNDEF;
3585 isym->st_other = STV_DEFAULT
3586 | (isym->st_other & ~ ELF_ST_VISIBILITY(-1));
3588 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3589 value -= sec->vma;
3591 else if (isym->st_shndx == SHN_ABS)
3592 sec = bfd_abs_section_ptr;
3593 else if (isym->st_shndx == SHN_COMMON)
3595 sec = bfd_com_section_ptr;
3596 /* What ELF calls the size we call the value. What ELF
3597 calls the value we call the alignment. */
3598 value = isym->st_size;
3600 else
3602 /* Leave it up to the processor backend. */
3605 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3606 isym->st_name);
3607 if (name == NULL)
3608 goto error_free_vers;
3610 if (isym->st_shndx == SHN_COMMON
3611 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3613 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3615 if (tcomm == NULL)
3617 tcomm = bfd_make_section (abfd, ".tcommon");
3618 if (tcomm == NULL
3619 || !bfd_set_section_flags (abfd, tcomm, (SEC_ALLOC
3620 | SEC_IS_COMMON
3621 | SEC_LINKER_CREATED
3622 | SEC_THREAD_LOCAL)))
3623 goto error_free_vers;
3625 sec = tcomm;
3627 else if (add_symbol_hook)
3629 if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec,
3630 &value))
3631 goto error_free_vers;
3633 /* The hook function sets the name to NULL if this symbol
3634 should be skipped for some reason. */
3635 if (name == NULL)
3636 continue;
3639 /* Sanity check that all possibilities were handled. */
3640 if (sec == NULL)
3642 bfd_set_error (bfd_error_bad_value);
3643 goto error_free_vers;
3646 if (bfd_is_und_section (sec)
3647 || bfd_is_com_section (sec))
3648 definition = FALSE;
3649 else
3650 definition = TRUE;
3652 size_change_ok = FALSE;
3653 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
3654 old_alignment = 0;
3655 old_bfd = NULL;
3656 new_sec = sec;
3658 if (is_elf_hash_table (hash_table))
3660 Elf_Internal_Versym iver;
3661 unsigned int vernum = 0;
3662 bfd_boolean skip;
3664 if (ever == NULL)
3666 if (info->default_imported_symver)
3667 /* Use the default symbol version created earlier. */
3668 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3669 else
3670 iver.vs_vers = 0;
3672 else
3673 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3675 vernum = iver.vs_vers & VERSYM_VERSION;
3677 /* If this is a hidden symbol, or if it is not version
3678 1, we append the version name to the symbol name.
3679 However, we do not modify a non-hidden absolute
3680 symbol, because it might be the version symbol
3681 itself. FIXME: What if it isn't? */
3682 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3683 || (vernum > 1 && ! bfd_is_abs_section (sec)))
3685 const char *verstr;
3686 size_t namelen, verlen, newlen;
3687 char *newname, *p;
3689 if (isym->st_shndx != SHN_UNDEF)
3691 if (vernum > elf_tdata (abfd)->cverdefs)
3692 verstr = NULL;
3693 else if (vernum > 1)
3694 verstr =
3695 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3696 else
3697 verstr = "";
3699 if (verstr == NULL)
3701 (*_bfd_error_handler)
3702 (_("%B: %s: invalid version %u (max %d)"),
3703 abfd, name, vernum,
3704 elf_tdata (abfd)->cverdefs);
3705 bfd_set_error (bfd_error_bad_value);
3706 goto error_free_vers;
3709 else
3711 /* We cannot simply test for the number of
3712 entries in the VERNEED section since the
3713 numbers for the needed versions do not start
3714 at 0. */
3715 Elf_Internal_Verneed *t;
3717 verstr = NULL;
3718 for (t = elf_tdata (abfd)->verref;
3719 t != NULL;
3720 t = t->vn_nextref)
3722 Elf_Internal_Vernaux *a;
3724 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3726 if (a->vna_other == vernum)
3728 verstr = a->vna_nodename;
3729 break;
3732 if (a != NULL)
3733 break;
3735 if (verstr == NULL)
3737 (*_bfd_error_handler)
3738 (_("%B: %s: invalid needed version %d"),
3739 abfd, name, vernum);
3740 bfd_set_error (bfd_error_bad_value);
3741 goto error_free_vers;
3745 namelen = strlen (name);
3746 verlen = strlen (verstr);
3747 newlen = namelen + verlen + 2;
3748 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3749 && isym->st_shndx != SHN_UNDEF)
3750 ++newlen;
3752 newname = bfd_alloc (abfd, newlen);
3753 if (newname == NULL)
3754 goto error_free_vers;
3755 memcpy (newname, name, namelen);
3756 p = newname + namelen;
3757 *p++ = ELF_VER_CHR;
3758 /* If this is a defined non-hidden version symbol,
3759 we add another @ to the name. This indicates the
3760 default version of the symbol. */
3761 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3762 && isym->st_shndx != SHN_UNDEF)
3763 *p++ = ELF_VER_CHR;
3764 memcpy (p, verstr, verlen + 1);
3766 name = newname;
3769 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
3770 &value, &old_alignment,
3771 sym_hash, &skip, &override,
3772 &type_change_ok, &size_change_ok))
3773 goto error_free_vers;
3775 if (skip)
3776 continue;
3778 if (override)
3779 definition = FALSE;
3781 h = *sym_hash;
3782 while (h->root.type == bfd_link_hash_indirect
3783 || h->root.type == bfd_link_hash_warning)
3784 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3786 /* Remember the old alignment if this is a common symbol, so
3787 that we don't reduce the alignment later on. We can't
3788 check later, because _bfd_generic_link_add_one_symbol
3789 will set a default for the alignment which we want to
3790 override. We also remember the old bfd where the existing
3791 definition comes from. */
3792 switch (h->root.type)
3794 default:
3795 break;
3797 case bfd_link_hash_defined:
3798 case bfd_link_hash_defweak:
3799 old_bfd = h->root.u.def.section->owner;
3800 break;
3802 case bfd_link_hash_common:
3803 old_bfd = h->root.u.c.p->section->owner;
3804 old_alignment = h->root.u.c.p->alignment_power;
3805 break;
3808 if (elf_tdata (abfd)->verdef != NULL
3809 && ! override
3810 && vernum > 1
3811 && definition)
3812 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3815 if (! (_bfd_generic_link_add_one_symbol
3816 (info, abfd, name, flags, sec, value, NULL, FALSE, collect,
3817 (struct bfd_link_hash_entry **) sym_hash)))
3818 goto error_free_vers;
3820 h = *sym_hash;
3821 while (h->root.type == bfd_link_hash_indirect
3822 || h->root.type == bfd_link_hash_warning)
3823 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3824 *sym_hash = h;
3826 new_weakdef = FALSE;
3827 if (dynamic
3828 && definition
3829 && (flags & BSF_WEAK) != 0
3830 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3831 && is_elf_hash_table (hash_table)
3832 && h->u.weakdef == NULL)
3834 /* Keep a list of all weak defined non function symbols from
3835 a dynamic object, using the weakdef field. Later in this
3836 function we will set the weakdef field to the correct
3837 value. We only put non-function symbols from dynamic
3838 objects on this list, because that happens to be the only
3839 time we need to know the normal symbol corresponding to a
3840 weak symbol, and the information is time consuming to
3841 figure out. If the weakdef field is not already NULL,
3842 then this symbol was already defined by some previous
3843 dynamic object, and we will be using that previous
3844 definition anyhow. */
3846 h->u.weakdef = weaks;
3847 weaks = h;
3848 new_weakdef = TRUE;
3851 /* Set the alignment of a common symbol. */
3852 if ((isym->st_shndx == SHN_COMMON
3853 || bfd_is_com_section (sec))
3854 && h->root.type == bfd_link_hash_common)
3856 unsigned int align;
3858 if (isym->st_shndx == SHN_COMMON)
3859 align = bfd_log2 (isym->st_value);
3860 else
3862 /* The new symbol is a common symbol in a shared object.
3863 We need to get the alignment from the section. */
3864 align = new_sec->alignment_power;
3866 if (align > old_alignment
3867 /* Permit an alignment power of zero if an alignment of one
3868 is specified and no other alignments have been specified. */
3869 || (isym->st_value == 1 && old_alignment == 0))
3870 h->root.u.c.p->alignment_power = align;
3871 else
3872 h->root.u.c.p->alignment_power = old_alignment;
3875 if (is_elf_hash_table (hash_table))
3877 bfd_boolean dynsym;
3879 /* Check the alignment when a common symbol is involved. This
3880 can change when a common symbol is overridden by a normal
3881 definition or a common symbol is ignored due to the old
3882 normal definition. We need to make sure the maximum
3883 alignment is maintained. */
3884 if ((old_alignment || isym->st_shndx == SHN_COMMON)
3885 && h->root.type != bfd_link_hash_common)
3887 unsigned int common_align;
3888 unsigned int normal_align;
3889 unsigned int symbol_align;
3890 bfd *normal_bfd;
3891 bfd *common_bfd;
3893 symbol_align = ffs (h->root.u.def.value) - 1;
3894 if (h->root.u.def.section->owner != NULL
3895 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3897 normal_align = h->root.u.def.section->alignment_power;
3898 if (normal_align > symbol_align)
3899 normal_align = symbol_align;
3901 else
3902 normal_align = symbol_align;
3904 if (old_alignment)
3906 common_align = old_alignment;
3907 common_bfd = old_bfd;
3908 normal_bfd = abfd;
3910 else
3912 common_align = bfd_log2 (isym->st_value);
3913 common_bfd = abfd;
3914 normal_bfd = old_bfd;
3917 if (normal_align < common_align)
3918 (*_bfd_error_handler)
3919 (_("Warning: alignment %u of symbol `%s' in %B"
3920 " is smaller than %u in %B"),
3921 normal_bfd, common_bfd,
3922 1 << normal_align, name, 1 << common_align);
3925 /* Remember the symbol size and type. */
3926 if (isym->st_size != 0
3927 && (definition || h->size == 0))
3929 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3930 (*_bfd_error_handler)
3931 (_("Warning: size of symbol `%s' changed"
3932 " from %lu in %B to %lu in %B"),
3933 old_bfd, abfd,
3934 name, (unsigned long) h->size,
3935 (unsigned long) isym->st_size);
3937 h->size = isym->st_size;
3940 /* If this is a common symbol, then we always want H->SIZE
3941 to be the size of the common symbol. The code just above
3942 won't fix the size if a common symbol becomes larger. We
3943 don't warn about a size change here, because that is
3944 covered by --warn-common. */
3945 if (h->root.type == bfd_link_hash_common)
3946 h->size = h->root.u.c.size;
3948 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3949 && (definition || h->type == STT_NOTYPE))
3951 if (h->type != STT_NOTYPE
3952 && h->type != ELF_ST_TYPE (isym->st_info)
3953 && ! type_change_ok)
3954 (*_bfd_error_handler)
3955 (_("Warning: type of symbol `%s' changed"
3956 " from %d to %d in %B"),
3957 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
3959 h->type = ELF_ST_TYPE (isym->st_info);
3962 /* If st_other has a processor-specific meaning, specific
3963 code might be needed here. We never merge the visibility
3964 attribute with the one from a dynamic object. */
3965 if (bed->elf_backend_merge_symbol_attribute)
3966 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3967 dynamic);
3969 /* If this symbol has default visibility and the user has requested
3970 we not re-export it, then mark it as hidden. */
3971 if (definition && !dynamic
3972 && (abfd->no_export
3973 || (abfd->my_archive && abfd->my_archive->no_export))
3974 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
3975 isym->st_other = STV_HIDDEN | (isym->st_other & ~ ELF_ST_VISIBILITY (-1));
3977 if (isym->st_other != 0 && !dynamic)
3979 unsigned char hvis, symvis, other, nvis;
3981 /* Take the balance of OTHER from the definition. */
3982 other = (definition ? isym->st_other : h->other);
3983 other &= ~ ELF_ST_VISIBILITY (-1);
3985 /* Combine visibilities, using the most constraining one. */
3986 hvis = ELF_ST_VISIBILITY (h->other);
3987 symvis = ELF_ST_VISIBILITY (isym->st_other);
3988 if (! hvis)
3989 nvis = symvis;
3990 else if (! symvis)
3991 nvis = hvis;
3992 else
3993 nvis = hvis < symvis ? hvis : symvis;
3995 h->other = other | nvis;
3998 /* Set a flag in the hash table entry indicating the type of
3999 reference or definition we just found. Keep a count of
4000 the number of dynamic symbols we find. A dynamic symbol
4001 is one which is referenced or defined by both a regular
4002 object and a shared object. */
4003 dynsym = FALSE;
4004 if (! dynamic)
4006 if (! definition)
4008 h->ref_regular = 1;
4009 if (bind != STB_WEAK)
4010 h->ref_regular_nonweak = 1;
4012 else
4013 h->def_regular = 1;
4014 if (! info->executable
4015 || h->def_dynamic
4016 || h->ref_dynamic)
4017 dynsym = TRUE;
4019 else
4021 if (! definition)
4022 h->ref_dynamic = 1;
4023 else
4024 h->def_dynamic = 1;
4025 if (h->def_regular
4026 || h->ref_regular
4027 || (h->u.weakdef != NULL
4028 && ! new_weakdef
4029 && h->u.weakdef->dynindx != -1))
4030 dynsym = TRUE;
4033 /* Check to see if we need to add an indirect symbol for
4034 the default name. */
4035 if (definition || h->root.type == bfd_link_hash_common)
4036 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4037 &sec, &value, &dynsym,
4038 override))
4039 goto error_free_vers;
4041 if (definition && !dynamic)
4043 char *p = strchr (name, ELF_VER_CHR);
4044 if (p != NULL && p[1] != ELF_VER_CHR)
4046 /* Queue non-default versions so that .symver x, x@FOO
4047 aliases can be checked. */
4048 if (! nondeflt_vers)
4050 amt = (isymend - isym + 1)
4051 * sizeof (struct elf_link_hash_entry *);
4052 nondeflt_vers = bfd_malloc (amt);
4054 nondeflt_vers [nondeflt_vers_cnt++] = h;
4058 if (dynsym && h->dynindx == -1)
4060 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4061 goto error_free_vers;
4062 if (h->u.weakdef != NULL
4063 && ! new_weakdef
4064 && h->u.weakdef->dynindx == -1)
4066 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4067 goto error_free_vers;
4070 else if (dynsym && h->dynindx != -1)
4071 /* If the symbol already has a dynamic index, but
4072 visibility says it should not be visible, turn it into
4073 a local symbol. */
4074 switch (ELF_ST_VISIBILITY (h->other))
4076 case STV_INTERNAL:
4077 case STV_HIDDEN:
4078 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4079 dynsym = FALSE;
4080 break;
4083 if (!add_needed
4084 && definition
4085 && dynsym
4086 && h->ref_regular)
4088 int ret;
4089 const char *soname = elf_dt_name (abfd);
4091 /* A symbol from a library loaded via DT_NEEDED of some
4092 other library is referenced by a regular object.
4093 Add a DT_NEEDED entry for it. Issue an error if
4094 --no-add-needed is used. */
4095 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4097 (*_bfd_error_handler)
4098 (_("%s: invalid DSO for symbol `%s' definition"),
4099 abfd, name);
4100 bfd_set_error (bfd_error_bad_value);
4101 goto error_free_vers;
4104 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4106 add_needed = TRUE;
4107 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4108 if (ret < 0)
4109 goto error_free_vers;
4111 BFD_ASSERT (ret == 0);
4116 /* Now that all the symbols from this input file are created, handle
4117 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4118 if (nondeflt_vers != NULL)
4120 bfd_size_type cnt, symidx;
4122 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4124 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4125 char *shortname, *p;
4127 p = strchr (h->root.root.string, ELF_VER_CHR);
4128 if (p == NULL
4129 || (h->root.type != bfd_link_hash_defined
4130 && h->root.type != bfd_link_hash_defweak))
4131 continue;
4133 amt = p - h->root.root.string;
4134 shortname = bfd_malloc (amt + 1);
4135 memcpy (shortname, h->root.root.string, amt);
4136 shortname[amt] = '\0';
4138 hi = (struct elf_link_hash_entry *)
4139 bfd_link_hash_lookup (&hash_table->root, shortname,
4140 FALSE, FALSE, FALSE);
4141 if (hi != NULL
4142 && hi->root.type == h->root.type
4143 && hi->root.u.def.value == h->root.u.def.value
4144 && hi->root.u.def.section == h->root.u.def.section)
4146 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4147 hi->root.type = bfd_link_hash_indirect;
4148 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4149 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
4150 sym_hash = elf_sym_hashes (abfd);
4151 if (sym_hash)
4152 for (symidx = 0; symidx < extsymcount; ++symidx)
4153 if (sym_hash[symidx] == hi)
4155 sym_hash[symidx] = h;
4156 break;
4159 free (shortname);
4161 free (nondeflt_vers);
4162 nondeflt_vers = NULL;
4165 if (extversym != NULL)
4167 free (extversym);
4168 extversym = NULL;
4171 if (isymbuf != NULL)
4172 free (isymbuf);
4173 isymbuf = NULL;
4175 if (!add_needed
4176 && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4178 /* Remove symbols defined in an as-needed shared lib that wasn't
4179 needed. */
4180 struct elf_smash_syms_data inf;
4181 inf.not_needed = abfd;
4182 inf.htab = hash_table;
4183 inf.twiddled = FALSE;
4184 elf_link_hash_traverse (hash_table, elf_smash_syms, &inf);
4185 if (inf.twiddled)
4186 bfd_link_repair_undef_list (&hash_table->root);
4187 weaks = NULL;
4190 /* Now set the weakdefs field correctly for all the weak defined
4191 symbols we found. The only way to do this is to search all the
4192 symbols. Since we only need the information for non functions in
4193 dynamic objects, that's the only time we actually put anything on
4194 the list WEAKS. We need this information so that if a regular
4195 object refers to a symbol defined weakly in a dynamic object, the
4196 real symbol in the dynamic object is also put in the dynamic
4197 symbols; we also must arrange for both symbols to point to the
4198 same memory location. We could handle the general case of symbol
4199 aliasing, but a general symbol alias can only be generated in
4200 assembler code, handling it correctly would be very time
4201 consuming, and other ELF linkers don't handle general aliasing
4202 either. */
4203 if (weaks != NULL)
4205 struct elf_link_hash_entry **hpp;
4206 struct elf_link_hash_entry **hppend;
4207 struct elf_link_hash_entry **sorted_sym_hash;
4208 struct elf_link_hash_entry *h;
4209 size_t sym_count;
4211 /* Since we have to search the whole symbol list for each weak
4212 defined symbol, search time for N weak defined symbols will be
4213 O(N^2). Binary search will cut it down to O(NlogN). */
4214 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4215 sorted_sym_hash = bfd_malloc (amt);
4216 if (sorted_sym_hash == NULL)
4217 goto error_return;
4218 sym_hash = sorted_sym_hash;
4219 hpp = elf_sym_hashes (abfd);
4220 hppend = hpp + extsymcount;
4221 sym_count = 0;
4222 for (; hpp < hppend; hpp++)
4224 h = *hpp;
4225 if (h != NULL
4226 && h->root.type == bfd_link_hash_defined
4227 && h->type != STT_FUNC)
4229 *sym_hash = h;
4230 sym_hash++;
4231 sym_count++;
4235 qsort (sorted_sym_hash, sym_count,
4236 sizeof (struct elf_link_hash_entry *),
4237 elf_sort_symbol);
4239 while (weaks != NULL)
4241 struct elf_link_hash_entry *hlook;
4242 asection *slook;
4243 bfd_vma vlook;
4244 long ilook;
4245 size_t i, j, idx;
4247 hlook = weaks;
4248 weaks = hlook->u.weakdef;
4249 hlook->u.weakdef = NULL;
4251 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4252 || hlook->root.type == bfd_link_hash_defweak
4253 || hlook->root.type == bfd_link_hash_common
4254 || hlook->root.type == bfd_link_hash_indirect);
4255 slook = hlook->root.u.def.section;
4256 vlook = hlook->root.u.def.value;
4258 ilook = -1;
4259 i = 0;
4260 j = sym_count;
4261 while (i < j)
4263 bfd_signed_vma vdiff;
4264 idx = (i + j) / 2;
4265 h = sorted_sym_hash [idx];
4266 vdiff = vlook - h->root.u.def.value;
4267 if (vdiff < 0)
4268 j = idx;
4269 else if (vdiff > 0)
4270 i = idx + 1;
4271 else
4273 long sdiff = slook->id - h->root.u.def.section->id;
4274 if (sdiff < 0)
4275 j = idx;
4276 else if (sdiff > 0)
4277 i = idx + 1;
4278 else
4280 ilook = idx;
4281 break;
4286 /* We didn't find a value/section match. */
4287 if (ilook == -1)
4288 continue;
4290 for (i = ilook; i < sym_count; i++)
4292 h = sorted_sym_hash [i];
4294 /* Stop if value or section doesn't match. */
4295 if (h->root.u.def.value != vlook
4296 || h->root.u.def.section != slook)
4297 break;
4298 else if (h != hlook)
4300 hlook->u.weakdef = h;
4302 /* If the weak definition is in the list of dynamic
4303 symbols, make sure the real definition is put
4304 there as well. */
4305 if (hlook->dynindx != -1 && h->dynindx == -1)
4307 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4308 goto error_return;
4311 /* If the real definition is in the list of dynamic
4312 symbols, make sure the weak definition is put
4313 there as well. If we don't do this, then the
4314 dynamic loader might not merge the entries for the
4315 real definition and the weak definition. */
4316 if (h->dynindx != -1 && hlook->dynindx == -1)
4318 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4319 goto error_return;
4321 break;
4326 free (sorted_sym_hash);
4329 check_directives = get_elf_backend_data (abfd)->check_directives;
4330 if (check_directives)
4331 check_directives (abfd, info);
4333 /* If this object is the same format as the output object, and it is
4334 not a shared library, then let the backend look through the
4335 relocs.
4337 This is required to build global offset table entries and to
4338 arrange for dynamic relocs. It is not required for the
4339 particular common case of linking non PIC code, even when linking
4340 against shared libraries, but unfortunately there is no way of
4341 knowing whether an object file has been compiled PIC or not.
4342 Looking through the relocs is not particularly time consuming.
4343 The problem is that we must either (1) keep the relocs in memory,
4344 which causes the linker to require additional runtime memory or
4345 (2) read the relocs twice from the input file, which wastes time.
4346 This would be a good case for using mmap.
4348 I have no idea how to handle linking PIC code into a file of a
4349 different format. It probably can't be done. */
4350 check_relocs = get_elf_backend_data (abfd)->check_relocs;
4351 if (! dynamic
4352 && is_elf_hash_table (hash_table)
4353 && hash_table->root.creator == abfd->xvec
4354 && check_relocs != NULL)
4356 asection *o;
4358 for (o = abfd->sections; o != NULL; o = o->next)
4360 Elf_Internal_Rela *internal_relocs;
4361 bfd_boolean ok;
4363 if ((o->flags & SEC_RELOC) == 0
4364 || o->reloc_count == 0
4365 || ((info->strip == strip_all || info->strip == strip_debugger)
4366 && (o->flags & SEC_DEBUGGING) != 0)
4367 || bfd_is_abs_section (o->output_section))
4368 continue;
4370 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4371 info->keep_memory);
4372 if (internal_relocs == NULL)
4373 goto error_return;
4375 ok = (*check_relocs) (abfd, info, o, internal_relocs);
4377 if (elf_section_data (o)->relocs != internal_relocs)
4378 free (internal_relocs);
4380 if (! ok)
4381 goto error_return;
4385 /* If this is a non-traditional link, try to optimize the handling
4386 of the .stab/.stabstr sections. */
4387 if (! dynamic
4388 && ! info->traditional_format
4389 && is_elf_hash_table (hash_table)
4390 && (info->strip != strip_all && info->strip != strip_debugger))
4392 asection *stabstr;
4394 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4395 if (stabstr != NULL)
4397 bfd_size_type string_offset = 0;
4398 asection *stab;
4400 for (stab = abfd->sections; stab; stab = stab->next)
4401 if (strncmp (".stab", stab->name, 5) == 0
4402 && (!stab->name[5] ||
4403 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4404 && (stab->flags & SEC_MERGE) == 0
4405 && !bfd_is_abs_section (stab->output_section))
4407 struct bfd_elf_section_data *secdata;
4409 secdata = elf_section_data (stab);
4410 if (! _bfd_link_section_stabs (abfd,
4411 &hash_table->stab_info,
4412 stab, stabstr,
4413 &secdata->sec_info,
4414 &string_offset))
4415 goto error_return;
4416 if (secdata->sec_info)
4417 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4422 if (is_elf_hash_table (hash_table) && add_needed)
4424 /* Add this bfd to the loaded list. */
4425 struct elf_link_loaded_list *n;
4427 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4428 if (n == NULL)
4429 goto error_return;
4430 n->abfd = abfd;
4431 n->next = hash_table->loaded;
4432 hash_table->loaded = n;
4435 return TRUE;
4437 error_free_vers:
4438 if (nondeflt_vers != NULL)
4439 free (nondeflt_vers);
4440 if (extversym != NULL)
4441 free (extversym);
4442 error_free_sym:
4443 if (isymbuf != NULL)
4444 free (isymbuf);
4445 error_return:
4446 return FALSE;
4449 /* Return the linker hash table entry of a symbol that might be
4450 satisfied by an archive symbol. Return -1 on error. */
4452 struct elf_link_hash_entry *
4453 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4454 struct bfd_link_info *info,
4455 const char *name)
4457 struct elf_link_hash_entry *h;
4458 char *p, *copy;
4459 size_t len, first;
4461 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4462 if (h != NULL)
4463 return h;
4465 /* If this is a default version (the name contains @@), look up the
4466 symbol again with only one `@' as well as without the version.
4467 The effect is that references to the symbol with and without the
4468 version will be matched by the default symbol in the archive. */
4470 p = strchr (name, ELF_VER_CHR);
4471 if (p == NULL || p[1] != ELF_VER_CHR)
4472 return h;
4474 /* First check with only one `@'. */
4475 len = strlen (name);
4476 copy = bfd_alloc (abfd, len);
4477 if (copy == NULL)
4478 return (struct elf_link_hash_entry *) 0 - 1;
4480 first = p - name + 1;
4481 memcpy (copy, name, first);
4482 memcpy (copy + first, name + first + 1, len - first);
4484 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4485 if (h == NULL)
4487 /* We also need to check references to the symbol without the
4488 version. */
4489 copy[first - 1] = '\0';
4490 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4491 FALSE, FALSE, FALSE);
4494 bfd_release (abfd, copy);
4495 return h;
4498 /* Add symbols from an ELF archive file to the linker hash table. We
4499 don't use _bfd_generic_link_add_archive_symbols because of a
4500 problem which arises on UnixWare. The UnixWare libc.so is an
4501 archive which includes an entry libc.so.1 which defines a bunch of
4502 symbols. The libc.so archive also includes a number of other
4503 object files, which also define symbols, some of which are the same
4504 as those defined in libc.so.1. Correct linking requires that we
4505 consider each object file in turn, and include it if it defines any
4506 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4507 this; it looks through the list of undefined symbols, and includes
4508 any object file which defines them. When this algorithm is used on
4509 UnixWare, it winds up pulling in libc.so.1 early and defining a
4510 bunch of symbols. This means that some of the other objects in the
4511 archive are not included in the link, which is incorrect since they
4512 precede libc.so.1 in the archive.
4514 Fortunately, ELF archive handling is simpler than that done by
4515 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4516 oddities. In ELF, if we find a symbol in the archive map, and the
4517 symbol is currently undefined, we know that we must pull in that
4518 object file.
4520 Unfortunately, we do have to make multiple passes over the symbol
4521 table until nothing further is resolved. */
4523 static bfd_boolean
4524 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4526 symindex c;
4527 bfd_boolean *defined = NULL;
4528 bfd_boolean *included = NULL;
4529 carsym *symdefs;
4530 bfd_boolean loop;
4531 bfd_size_type amt;
4532 const struct elf_backend_data *bed;
4533 struct elf_link_hash_entry * (*archive_symbol_lookup)
4534 (bfd *, struct bfd_link_info *, const char *);
4536 if (! bfd_has_map (abfd))
4538 /* An empty archive is a special case. */
4539 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4540 return TRUE;
4541 bfd_set_error (bfd_error_no_armap);
4542 return FALSE;
4545 /* Keep track of all symbols we know to be already defined, and all
4546 files we know to be already included. This is to speed up the
4547 second and subsequent passes. */
4548 c = bfd_ardata (abfd)->symdef_count;
4549 if (c == 0)
4550 return TRUE;
4551 amt = c;
4552 amt *= sizeof (bfd_boolean);
4553 defined = bfd_zmalloc (amt);
4554 included = bfd_zmalloc (amt);
4555 if (defined == NULL || included == NULL)
4556 goto error_return;
4558 symdefs = bfd_ardata (abfd)->symdefs;
4559 bed = get_elf_backend_data (abfd);
4560 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4564 file_ptr last;
4565 symindex i;
4566 carsym *symdef;
4567 carsym *symdefend;
4569 loop = FALSE;
4570 last = -1;
4572 symdef = symdefs;
4573 symdefend = symdef + c;
4574 for (i = 0; symdef < symdefend; symdef++, i++)
4576 struct elf_link_hash_entry *h;
4577 bfd *element;
4578 struct bfd_link_hash_entry *undefs_tail;
4579 symindex mark;
4581 if (defined[i] || included[i])
4582 continue;
4583 if (symdef->file_offset == last)
4585 included[i] = TRUE;
4586 continue;
4589 h = archive_symbol_lookup (abfd, info, symdef->name);
4590 if (h == (struct elf_link_hash_entry *) 0 - 1)
4591 goto error_return;
4593 if (h == NULL)
4594 continue;
4596 if (h->root.type == bfd_link_hash_common)
4598 /* We currently have a common symbol. The archive map contains
4599 a reference to this symbol, so we may want to include it. We
4600 only want to include it however, if this archive element
4601 contains a definition of the symbol, not just another common
4602 declaration of it.
4604 Unfortunately some archivers (including GNU ar) will put
4605 declarations of common symbols into their archive maps, as
4606 well as real definitions, so we cannot just go by the archive
4607 map alone. Instead we must read in the element's symbol
4608 table and check that to see what kind of symbol definition
4609 this is. */
4610 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4611 continue;
4613 else if (h->root.type != bfd_link_hash_undefined)
4615 if (h->root.type != bfd_link_hash_undefweak)
4616 defined[i] = TRUE;
4617 continue;
4620 /* We need to include this archive member. */
4621 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4622 if (element == NULL)
4623 goto error_return;
4625 if (! bfd_check_format (element, bfd_object))
4626 goto error_return;
4628 /* Doublecheck that we have not included this object
4629 already--it should be impossible, but there may be
4630 something wrong with the archive. */
4631 if (element->archive_pass != 0)
4633 bfd_set_error (bfd_error_bad_value);
4634 goto error_return;
4636 element->archive_pass = 1;
4638 undefs_tail = info->hash->undefs_tail;
4640 if (! (*info->callbacks->add_archive_element) (info, element,
4641 symdef->name))
4642 goto error_return;
4643 if (! bfd_link_add_symbols (element, info))
4644 goto error_return;
4646 /* If there are any new undefined symbols, we need to make
4647 another pass through the archive in order to see whether
4648 they can be defined. FIXME: This isn't perfect, because
4649 common symbols wind up on undefs_tail and because an
4650 undefined symbol which is defined later on in this pass
4651 does not require another pass. This isn't a bug, but it
4652 does make the code less efficient than it could be. */
4653 if (undefs_tail != info->hash->undefs_tail)
4654 loop = TRUE;
4656 /* Look backward to mark all symbols from this object file
4657 which we have already seen in this pass. */
4658 mark = i;
4661 included[mark] = TRUE;
4662 if (mark == 0)
4663 break;
4664 --mark;
4666 while (symdefs[mark].file_offset == symdef->file_offset);
4668 /* We mark subsequent symbols from this object file as we go
4669 on through the loop. */
4670 last = symdef->file_offset;
4673 while (loop);
4675 free (defined);
4676 free (included);
4678 return TRUE;
4680 error_return:
4681 if (defined != NULL)
4682 free (defined);
4683 if (included != NULL)
4684 free (included);
4685 return FALSE;
4688 /* Given an ELF BFD, add symbols to the global hash table as
4689 appropriate. */
4691 bfd_boolean
4692 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4694 switch (bfd_get_format (abfd))
4696 case bfd_object:
4697 return elf_link_add_object_symbols (abfd, info);
4698 case bfd_archive:
4699 return elf_link_add_archive_symbols (abfd, info);
4700 default:
4701 bfd_set_error (bfd_error_wrong_format);
4702 return FALSE;
4706 /* This function will be called though elf_link_hash_traverse to store
4707 all hash value of the exported symbols in an array. */
4709 static bfd_boolean
4710 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4712 unsigned long **valuep = data;
4713 const char *name;
4714 char *p;
4715 unsigned long ha;
4716 char *alc = NULL;
4718 if (h->root.type == bfd_link_hash_warning)
4719 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4721 /* Ignore indirect symbols. These are added by the versioning code. */
4722 if (h->dynindx == -1)
4723 return TRUE;
4725 name = h->root.root.string;
4726 p = strchr (name, ELF_VER_CHR);
4727 if (p != NULL)
4729 alc = bfd_malloc (p - name + 1);
4730 memcpy (alc, name, p - name);
4731 alc[p - name] = '\0';
4732 name = alc;
4735 /* Compute the hash value. */
4736 ha = bfd_elf_hash (name);
4738 /* Store the found hash value in the array given as the argument. */
4739 *(*valuep)++ = ha;
4741 /* And store it in the struct so that we can put it in the hash table
4742 later. */
4743 h->u.elf_hash_value = ha;
4745 if (alc != NULL)
4746 free (alc);
4748 return TRUE;
4751 /* Array used to determine the number of hash table buckets to use
4752 based on the number of symbols there are. If there are fewer than
4753 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4754 fewer than 37 we use 17 buckets, and so forth. We never use more
4755 than 32771 buckets. */
4757 static const size_t elf_buckets[] =
4759 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4760 16411, 32771, 0
4763 /* Compute bucket count for hashing table. We do not use a static set
4764 of possible tables sizes anymore. Instead we determine for all
4765 possible reasonable sizes of the table the outcome (i.e., the
4766 number of collisions etc) and choose the best solution. The
4767 weighting functions are not too simple to allow the table to grow
4768 without bounds. Instead one of the weighting factors is the size.
4769 Therefore the result is always a good payoff between few collisions
4770 (= short chain lengths) and table size. */
4771 static size_t
4772 compute_bucket_count (struct bfd_link_info *info)
4774 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4775 size_t best_size = 0;
4776 unsigned long int *hashcodes;
4777 unsigned long int *hashcodesp;
4778 unsigned long int i;
4779 bfd_size_type amt;
4781 /* Compute the hash values for all exported symbols. At the same
4782 time store the values in an array so that we could use them for
4783 optimizations. */
4784 amt = dynsymcount;
4785 amt *= sizeof (unsigned long int);
4786 hashcodes = bfd_malloc (amt);
4787 if (hashcodes == NULL)
4788 return 0;
4789 hashcodesp = hashcodes;
4791 /* Put all hash values in HASHCODES. */
4792 elf_link_hash_traverse (elf_hash_table (info),
4793 elf_collect_hash_codes, &hashcodesp);
4795 /* We have a problem here. The following code to optimize the table
4796 size requires an integer type with more the 32 bits. If
4797 BFD_HOST_U_64_BIT is set we know about such a type. */
4798 #ifdef BFD_HOST_U_64_BIT
4799 if (info->optimize)
4801 unsigned long int nsyms = hashcodesp - hashcodes;
4802 size_t minsize;
4803 size_t maxsize;
4804 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4805 unsigned long int *counts ;
4806 bfd *dynobj = elf_hash_table (info)->dynobj;
4807 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4809 /* Possible optimization parameters: if we have NSYMS symbols we say
4810 that the hashing table must at least have NSYMS/4 and at most
4811 2*NSYMS buckets. */
4812 minsize = nsyms / 4;
4813 if (minsize == 0)
4814 minsize = 1;
4815 best_size = maxsize = nsyms * 2;
4817 /* Create array where we count the collisions in. We must use bfd_malloc
4818 since the size could be large. */
4819 amt = maxsize;
4820 amt *= sizeof (unsigned long int);
4821 counts = bfd_malloc (amt);
4822 if (counts == NULL)
4824 free (hashcodes);
4825 return 0;
4828 /* Compute the "optimal" size for the hash table. The criteria is a
4829 minimal chain length. The minor criteria is (of course) the size
4830 of the table. */
4831 for (i = minsize; i < maxsize; ++i)
4833 /* Walk through the array of hashcodes and count the collisions. */
4834 BFD_HOST_U_64_BIT max;
4835 unsigned long int j;
4836 unsigned long int fact;
4838 memset (counts, '\0', i * sizeof (unsigned long int));
4840 /* Determine how often each hash bucket is used. */
4841 for (j = 0; j < nsyms; ++j)
4842 ++counts[hashcodes[j] % i];
4844 /* For the weight function we need some information about the
4845 pagesize on the target. This is information need not be 100%
4846 accurate. Since this information is not available (so far) we
4847 define it here to a reasonable default value. If it is crucial
4848 to have a better value some day simply define this value. */
4849 # ifndef BFD_TARGET_PAGESIZE
4850 # define BFD_TARGET_PAGESIZE (4096)
4851 # endif
4853 /* We in any case need 2 + NSYMS entries for the size values and
4854 the chains. */
4855 max = (2 + nsyms) * (bed->s->arch_size / 8);
4857 # if 1
4858 /* Variant 1: optimize for short chains. We add the squares
4859 of all the chain lengths (which favors many small chain
4860 over a few long chains). */
4861 for (j = 0; j < i; ++j)
4862 max += counts[j] * counts[j];
4864 /* This adds penalties for the overall size of the table. */
4865 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4866 max *= fact * fact;
4867 # else
4868 /* Variant 2: Optimize a lot more for small table. Here we
4869 also add squares of the size but we also add penalties for
4870 empty slots (the +1 term). */
4871 for (j = 0; j < i; ++j)
4872 max += (1 + counts[j]) * (1 + counts[j]);
4874 /* The overall size of the table is considered, but not as
4875 strong as in variant 1, where it is squared. */
4876 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4877 max *= fact;
4878 # endif
4880 /* Compare with current best results. */
4881 if (max < best_chlen)
4883 best_chlen = max;
4884 best_size = i;
4888 free (counts);
4890 else
4891 #endif /* defined (BFD_HOST_U_64_BIT) */
4893 /* This is the fallback solution if no 64bit type is available or if we
4894 are not supposed to spend much time on optimizations. We select the
4895 bucket count using a fixed set of numbers. */
4896 for (i = 0; elf_buckets[i] != 0; i++)
4898 best_size = elf_buckets[i];
4899 if (dynsymcount < elf_buckets[i + 1])
4900 break;
4904 /* Free the arrays we needed. */
4905 free (hashcodes);
4907 return best_size;
4910 /* Set up the sizes and contents of the ELF dynamic sections. This is
4911 called by the ELF linker emulation before_allocation routine. We
4912 must set the sizes of the sections before the linker sets the
4913 addresses of the various sections. */
4915 bfd_boolean
4916 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4917 const char *soname,
4918 const char *rpath,
4919 const char *filter_shlib,
4920 const char * const *auxiliary_filters,
4921 struct bfd_link_info *info,
4922 asection **sinterpptr,
4923 struct bfd_elf_version_tree *verdefs)
4925 bfd_size_type soname_indx;
4926 bfd *dynobj;
4927 const struct elf_backend_data *bed;
4928 struct elf_assign_sym_version_info asvinfo;
4930 *sinterpptr = NULL;
4932 soname_indx = (bfd_size_type) -1;
4934 if (!is_elf_hash_table (info->hash))
4935 return TRUE;
4937 elf_tdata (output_bfd)->relro = info->relro;
4938 if (info->execstack)
4939 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4940 else if (info->noexecstack)
4941 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4942 else
4944 bfd *inputobj;
4945 asection *notesec = NULL;
4946 int exec = 0;
4948 for (inputobj = info->input_bfds;
4949 inputobj;
4950 inputobj = inputobj->link_next)
4952 asection *s;
4954 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
4955 continue;
4956 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
4957 if (s)
4959 if (s->flags & SEC_CODE)
4960 exec = PF_X;
4961 notesec = s;
4963 else
4964 exec = PF_X;
4966 if (notesec)
4968 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
4969 if (exec && info->relocatable
4970 && notesec->output_section != bfd_abs_section_ptr)
4971 notesec->output_section->flags |= SEC_CODE;
4975 /* Any syms created from now on start with -1 in
4976 got.refcount/offset and plt.refcount/offset. */
4977 elf_hash_table (info)->init_refcount = elf_hash_table (info)->init_offset;
4979 /* The backend may have to create some sections regardless of whether
4980 we're dynamic or not. */
4981 bed = get_elf_backend_data (output_bfd);
4982 if (bed->elf_backend_always_size_sections
4983 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
4984 return FALSE;
4986 dynobj = elf_hash_table (info)->dynobj;
4988 /* If there were no dynamic objects in the link, there is nothing to
4989 do here. */
4990 if (dynobj == NULL)
4991 return TRUE;
4993 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
4994 return FALSE;
4996 if (elf_hash_table (info)->dynamic_sections_created)
4998 struct elf_info_failed eif;
4999 struct elf_link_hash_entry *h;
5000 asection *dynstr;
5001 struct bfd_elf_version_tree *t;
5002 struct bfd_elf_version_expr *d;
5003 bfd_boolean all_defined;
5005 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5006 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5008 if (soname != NULL)
5010 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5011 soname, TRUE);
5012 if (soname_indx == (bfd_size_type) -1
5013 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5014 return FALSE;
5017 if (info->symbolic)
5019 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5020 return FALSE;
5021 info->flags |= DF_SYMBOLIC;
5024 if (rpath != NULL)
5026 bfd_size_type indx;
5028 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5029 TRUE);
5030 if (indx == (bfd_size_type) -1
5031 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5032 return FALSE;
5034 if (info->new_dtags)
5036 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5037 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5038 return FALSE;
5042 if (filter_shlib != NULL)
5044 bfd_size_type indx;
5046 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5047 filter_shlib, TRUE);
5048 if (indx == (bfd_size_type) -1
5049 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5050 return FALSE;
5053 if (auxiliary_filters != NULL)
5055 const char * const *p;
5057 for (p = auxiliary_filters; *p != NULL; p++)
5059 bfd_size_type indx;
5061 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5062 *p, TRUE);
5063 if (indx == (bfd_size_type) -1
5064 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5065 return FALSE;
5069 eif.info = info;
5070 eif.verdefs = verdefs;
5071 eif.failed = FALSE;
5073 /* If we are supposed to export all symbols into the dynamic symbol
5074 table (this is not the normal case), then do so. */
5075 if (info->export_dynamic)
5077 elf_link_hash_traverse (elf_hash_table (info),
5078 _bfd_elf_export_symbol,
5079 &eif);
5080 if (eif.failed)
5081 return FALSE;
5084 /* Make all global versions with definition. */
5085 for (t = verdefs; t != NULL; t = t->next)
5086 for (d = t->globals.list; d != NULL; d = d->next)
5087 if (!d->symver && d->symbol)
5089 const char *verstr, *name;
5090 size_t namelen, verlen, newlen;
5091 char *newname, *p;
5092 struct elf_link_hash_entry *newh;
5094 name = d->symbol;
5095 namelen = strlen (name);
5096 verstr = t->name;
5097 verlen = strlen (verstr);
5098 newlen = namelen + verlen + 3;
5100 newname = bfd_malloc (newlen);
5101 if (newname == NULL)
5102 return FALSE;
5103 memcpy (newname, name, namelen);
5105 /* Check the hidden versioned definition. */
5106 p = newname + namelen;
5107 *p++ = ELF_VER_CHR;
5108 memcpy (p, verstr, verlen + 1);
5109 newh = elf_link_hash_lookup (elf_hash_table (info),
5110 newname, FALSE, FALSE,
5111 FALSE);
5112 if (newh == NULL
5113 || (newh->root.type != bfd_link_hash_defined
5114 && newh->root.type != bfd_link_hash_defweak))
5116 /* Check the default versioned definition. */
5117 *p++ = ELF_VER_CHR;
5118 memcpy (p, verstr, verlen + 1);
5119 newh = elf_link_hash_lookup (elf_hash_table (info),
5120 newname, FALSE, FALSE,
5121 FALSE);
5123 free (newname);
5125 /* Mark this version if there is a definition and it is
5126 not defined in a shared object. */
5127 if (newh != NULL
5128 && !newh->def_dynamic
5129 && (newh->root.type == bfd_link_hash_defined
5130 || newh->root.type == bfd_link_hash_defweak))
5131 d->symver = 1;
5134 /* Attach all the symbols to their version information. */
5135 asvinfo.output_bfd = output_bfd;
5136 asvinfo.info = info;
5137 asvinfo.verdefs = verdefs;
5138 asvinfo.failed = FALSE;
5140 elf_link_hash_traverse (elf_hash_table (info),
5141 _bfd_elf_link_assign_sym_version,
5142 &asvinfo);
5143 if (asvinfo.failed)
5144 return FALSE;
5146 if (!info->allow_undefined_version)
5148 /* Check if all global versions have a definition. */
5149 all_defined = TRUE;
5150 for (t = verdefs; t != NULL; t = t->next)
5151 for (d = t->globals.list; d != NULL; d = d->next)
5152 if (!d->symver && !d->script)
5154 (*_bfd_error_handler)
5155 (_("%s: undefined version: %s"),
5156 d->pattern, t->name);
5157 all_defined = FALSE;
5160 if (!all_defined)
5162 bfd_set_error (bfd_error_bad_value);
5163 return FALSE;
5167 /* Find all symbols which were defined in a dynamic object and make
5168 the backend pick a reasonable value for them. */
5169 elf_link_hash_traverse (elf_hash_table (info),
5170 _bfd_elf_adjust_dynamic_symbol,
5171 &eif);
5172 if (eif.failed)
5173 return FALSE;
5175 /* Add some entries to the .dynamic section. We fill in some of the
5176 values later, in bfd_elf_final_link, but we must add the entries
5177 now so that we know the final size of the .dynamic section. */
5179 /* If there are initialization and/or finalization functions to
5180 call then add the corresponding DT_INIT/DT_FINI entries. */
5181 h = (info->init_function
5182 ? elf_link_hash_lookup (elf_hash_table (info),
5183 info->init_function, FALSE,
5184 FALSE, FALSE)
5185 : NULL);
5186 if (h != NULL
5187 && (h->ref_regular
5188 || h->def_regular))
5190 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5191 return FALSE;
5193 h = (info->fini_function
5194 ? elf_link_hash_lookup (elf_hash_table (info),
5195 info->fini_function, FALSE,
5196 FALSE, FALSE)
5197 : NULL);
5198 if (h != NULL
5199 && (h->ref_regular
5200 || h->def_regular))
5202 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5203 return FALSE;
5206 if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL)
5208 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5209 if (! info->executable)
5211 bfd *sub;
5212 asection *o;
5214 for (sub = info->input_bfds; sub != NULL;
5215 sub = sub->link_next)
5216 for (o = sub->sections; o != NULL; o = o->next)
5217 if (elf_section_data (o)->this_hdr.sh_type
5218 == SHT_PREINIT_ARRAY)
5220 (*_bfd_error_handler)
5221 (_("%B: .preinit_array section is not allowed in DSO"),
5222 sub);
5223 break;
5226 bfd_set_error (bfd_error_nonrepresentable_section);
5227 return FALSE;
5230 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5231 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5232 return FALSE;
5234 if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL)
5236 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5237 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5238 return FALSE;
5240 if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL)
5242 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5243 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5244 return FALSE;
5247 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5248 /* If .dynstr is excluded from the link, we don't want any of
5249 these tags. Strictly, we should be checking each section
5250 individually; This quick check covers for the case where
5251 someone does a /DISCARD/ : { *(*) }. */
5252 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5254 bfd_size_type strsize;
5256 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5257 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
5258 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5259 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5260 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5261 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5262 bed->s->sizeof_sym))
5263 return FALSE;
5267 /* The backend must work out the sizes of all the other dynamic
5268 sections. */
5269 if (bed->elf_backend_size_dynamic_sections
5270 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5271 return FALSE;
5273 if (elf_hash_table (info)->dynamic_sections_created)
5275 bfd_size_type dynsymcount;
5276 asection *s;
5277 size_t bucketcount = 0;
5278 size_t hash_entry_size;
5279 unsigned int dtagcount;
5281 /* Set up the version definition section. */
5282 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5283 BFD_ASSERT (s != NULL);
5285 /* We may have created additional version definitions if we are
5286 just linking a regular application. */
5287 verdefs = asvinfo.verdefs;
5289 /* Skip anonymous version tag. */
5290 if (verdefs != NULL && verdefs->vernum == 0)
5291 verdefs = verdefs->next;
5293 if (verdefs == NULL && !info->create_default_symver)
5294 _bfd_strip_section_from_output (info, s);
5295 else
5297 unsigned int cdefs;
5298 bfd_size_type size;
5299 struct bfd_elf_version_tree *t;
5300 bfd_byte *p;
5301 Elf_Internal_Verdef def;
5302 Elf_Internal_Verdaux defaux;
5303 struct bfd_link_hash_entry *bh;
5304 struct elf_link_hash_entry *h;
5305 const char *name;
5307 cdefs = 0;
5308 size = 0;
5310 /* Make space for the base version. */
5311 size += sizeof (Elf_External_Verdef);
5312 size += sizeof (Elf_External_Verdaux);
5313 ++cdefs;
5315 /* Make space for the default version. */
5316 if (info->create_default_symver)
5318 size += sizeof (Elf_External_Verdef);
5319 ++cdefs;
5322 for (t = verdefs; t != NULL; t = t->next)
5324 struct bfd_elf_version_deps *n;
5326 size += sizeof (Elf_External_Verdef);
5327 size += sizeof (Elf_External_Verdaux);
5328 ++cdefs;
5330 for (n = t->deps; n != NULL; n = n->next)
5331 size += sizeof (Elf_External_Verdaux);
5334 s->size = size;
5335 s->contents = bfd_alloc (output_bfd, s->size);
5336 if (s->contents == NULL && s->size != 0)
5337 return FALSE;
5339 /* Fill in the version definition section. */
5341 p = s->contents;
5343 def.vd_version = VER_DEF_CURRENT;
5344 def.vd_flags = VER_FLG_BASE;
5345 def.vd_ndx = 1;
5346 def.vd_cnt = 1;
5347 if (info->create_default_symver)
5349 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5350 def.vd_next = sizeof (Elf_External_Verdef);
5352 else
5354 def.vd_aux = sizeof (Elf_External_Verdef);
5355 def.vd_next = (sizeof (Elf_External_Verdef)
5356 + sizeof (Elf_External_Verdaux));
5359 if (soname_indx != (bfd_size_type) -1)
5361 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5362 soname_indx);
5363 def.vd_hash = bfd_elf_hash (soname);
5364 defaux.vda_name = soname_indx;
5365 name = soname;
5367 else
5369 bfd_size_type indx;
5371 name = basename (output_bfd->filename);
5372 def.vd_hash = bfd_elf_hash (name);
5373 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5374 name, FALSE);
5375 if (indx == (bfd_size_type) -1)
5376 return FALSE;
5377 defaux.vda_name = indx;
5379 defaux.vda_next = 0;
5381 _bfd_elf_swap_verdef_out (output_bfd, &def,
5382 (Elf_External_Verdef *) p);
5383 p += sizeof (Elf_External_Verdef);
5384 if (info->create_default_symver)
5386 /* Add a symbol representing this version. */
5387 bh = NULL;
5388 if (! (_bfd_generic_link_add_one_symbol
5389 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5390 0, NULL, FALSE,
5391 get_elf_backend_data (dynobj)->collect, &bh)))
5392 return FALSE;
5393 h = (struct elf_link_hash_entry *) bh;
5394 h->non_elf = 0;
5395 h->def_regular = 1;
5396 h->type = STT_OBJECT;
5397 h->verinfo.vertree = NULL;
5399 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5400 return FALSE;
5402 /* Create a duplicate of the base version with the same
5403 aux block, but different flags. */
5404 def.vd_flags = 0;
5405 def.vd_ndx = 2;
5406 def.vd_aux = sizeof (Elf_External_Verdef);
5407 if (verdefs)
5408 def.vd_next = (sizeof (Elf_External_Verdef)
5409 + sizeof (Elf_External_Verdaux));
5410 else
5411 def.vd_next = 0;
5412 _bfd_elf_swap_verdef_out (output_bfd, &def,
5413 (Elf_External_Verdef *) p);
5414 p += sizeof (Elf_External_Verdef);
5416 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5417 (Elf_External_Verdaux *) p);
5418 p += sizeof (Elf_External_Verdaux);
5420 for (t = verdefs; t != NULL; t = t->next)
5422 unsigned int cdeps;
5423 struct bfd_elf_version_deps *n;
5425 cdeps = 0;
5426 for (n = t->deps; n != NULL; n = n->next)
5427 ++cdeps;
5429 /* Add a symbol representing this version. */
5430 bh = NULL;
5431 if (! (_bfd_generic_link_add_one_symbol
5432 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5433 0, NULL, FALSE,
5434 get_elf_backend_data (dynobj)->collect, &bh)))
5435 return FALSE;
5436 h = (struct elf_link_hash_entry *) bh;
5437 h->non_elf = 0;
5438 h->def_regular = 1;
5439 h->type = STT_OBJECT;
5440 h->verinfo.vertree = t;
5442 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5443 return FALSE;
5445 def.vd_version = VER_DEF_CURRENT;
5446 def.vd_flags = 0;
5447 if (t->globals.list == NULL
5448 && t->locals.list == NULL
5449 && ! t->used)
5450 def.vd_flags |= VER_FLG_WEAK;
5451 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5452 def.vd_cnt = cdeps + 1;
5453 def.vd_hash = bfd_elf_hash (t->name);
5454 def.vd_aux = sizeof (Elf_External_Verdef);
5455 def.vd_next = 0;
5456 if (t->next != NULL)
5457 def.vd_next = (sizeof (Elf_External_Verdef)
5458 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5460 _bfd_elf_swap_verdef_out (output_bfd, &def,
5461 (Elf_External_Verdef *) p);
5462 p += sizeof (Elf_External_Verdef);
5464 defaux.vda_name = h->dynstr_index;
5465 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5466 h->dynstr_index);
5467 defaux.vda_next = 0;
5468 if (t->deps != NULL)
5469 defaux.vda_next = sizeof (Elf_External_Verdaux);
5470 t->name_indx = defaux.vda_name;
5472 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5473 (Elf_External_Verdaux *) p);
5474 p += sizeof (Elf_External_Verdaux);
5476 for (n = t->deps; n != NULL; n = n->next)
5478 if (n->version_needed == NULL)
5480 /* This can happen if there was an error in the
5481 version script. */
5482 defaux.vda_name = 0;
5484 else
5486 defaux.vda_name = n->version_needed->name_indx;
5487 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5488 defaux.vda_name);
5490 if (n->next == NULL)
5491 defaux.vda_next = 0;
5492 else
5493 defaux.vda_next = sizeof (Elf_External_Verdaux);
5495 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5496 (Elf_External_Verdaux *) p);
5497 p += sizeof (Elf_External_Verdaux);
5501 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5502 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5503 return FALSE;
5505 elf_tdata (output_bfd)->cverdefs = cdefs;
5508 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5510 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5511 return FALSE;
5513 else if (info->flags & DF_BIND_NOW)
5515 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5516 return FALSE;
5519 if (info->flags_1)
5521 if (info->executable)
5522 info->flags_1 &= ~ (DF_1_INITFIRST
5523 | DF_1_NODELETE
5524 | DF_1_NOOPEN);
5525 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5526 return FALSE;
5529 /* Work out the size of the version reference section. */
5531 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5532 BFD_ASSERT (s != NULL);
5534 struct elf_find_verdep_info sinfo;
5536 sinfo.output_bfd = output_bfd;
5537 sinfo.info = info;
5538 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5539 if (sinfo.vers == 0)
5540 sinfo.vers = 1;
5541 sinfo.failed = FALSE;
5543 elf_link_hash_traverse (elf_hash_table (info),
5544 _bfd_elf_link_find_version_dependencies,
5545 &sinfo);
5547 if (elf_tdata (output_bfd)->verref == NULL)
5548 _bfd_strip_section_from_output (info, s);
5549 else
5551 Elf_Internal_Verneed *t;
5552 unsigned int size;
5553 unsigned int crefs;
5554 bfd_byte *p;
5556 /* Build the version definition section. */
5557 size = 0;
5558 crefs = 0;
5559 for (t = elf_tdata (output_bfd)->verref;
5560 t != NULL;
5561 t = t->vn_nextref)
5563 Elf_Internal_Vernaux *a;
5565 size += sizeof (Elf_External_Verneed);
5566 ++crefs;
5567 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5568 size += sizeof (Elf_External_Vernaux);
5571 s->size = size;
5572 s->contents = bfd_alloc (output_bfd, s->size);
5573 if (s->contents == NULL)
5574 return FALSE;
5576 p = s->contents;
5577 for (t = elf_tdata (output_bfd)->verref;
5578 t != NULL;
5579 t = t->vn_nextref)
5581 unsigned int caux;
5582 Elf_Internal_Vernaux *a;
5583 bfd_size_type indx;
5585 caux = 0;
5586 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5587 ++caux;
5589 t->vn_version = VER_NEED_CURRENT;
5590 t->vn_cnt = caux;
5591 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5592 elf_dt_name (t->vn_bfd) != NULL
5593 ? elf_dt_name (t->vn_bfd)
5594 : basename (t->vn_bfd->filename),
5595 FALSE);
5596 if (indx == (bfd_size_type) -1)
5597 return FALSE;
5598 t->vn_file = indx;
5599 t->vn_aux = sizeof (Elf_External_Verneed);
5600 if (t->vn_nextref == NULL)
5601 t->vn_next = 0;
5602 else
5603 t->vn_next = (sizeof (Elf_External_Verneed)
5604 + caux * sizeof (Elf_External_Vernaux));
5606 _bfd_elf_swap_verneed_out (output_bfd, t,
5607 (Elf_External_Verneed *) p);
5608 p += sizeof (Elf_External_Verneed);
5610 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5612 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5613 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5614 a->vna_nodename, FALSE);
5615 if (indx == (bfd_size_type) -1)
5616 return FALSE;
5617 a->vna_name = indx;
5618 if (a->vna_nextptr == NULL)
5619 a->vna_next = 0;
5620 else
5621 a->vna_next = sizeof (Elf_External_Vernaux);
5623 _bfd_elf_swap_vernaux_out (output_bfd, a,
5624 (Elf_External_Vernaux *) p);
5625 p += sizeof (Elf_External_Vernaux);
5629 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5630 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5631 return FALSE;
5633 elf_tdata (output_bfd)->cverrefs = crefs;
5637 /* Assign dynsym indicies. In a shared library we generate a
5638 section symbol for each output section, which come first.
5639 Next come all of the back-end allocated local dynamic syms,
5640 followed by the rest of the global symbols. */
5642 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5644 /* Work out the size of the symbol version section. */
5645 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5646 BFD_ASSERT (s != NULL);
5647 if (dynsymcount == 0
5648 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL
5649 && !info->create_default_symver))
5651 _bfd_strip_section_from_output (info, s);
5652 /* The DYNSYMCOUNT might have changed if we were going to
5653 output a dynamic symbol table entry for S. */
5654 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5656 else
5658 s->size = dynsymcount * sizeof (Elf_External_Versym);
5659 s->contents = bfd_zalloc (output_bfd, s->size);
5660 if (s->contents == NULL)
5661 return FALSE;
5663 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5664 return FALSE;
5667 /* Set the size of the .dynsym and .hash sections. We counted
5668 the number of dynamic symbols in elf_link_add_object_symbols.
5669 We will build the contents of .dynsym and .hash when we build
5670 the final symbol table, because until then we do not know the
5671 correct value to give the symbols. We built the .dynstr
5672 section as we went along in elf_link_add_object_symbols. */
5673 s = bfd_get_section_by_name (dynobj, ".dynsym");
5674 BFD_ASSERT (s != NULL);
5675 s->size = dynsymcount * bed->s->sizeof_sym;
5676 s->contents = bfd_alloc (output_bfd, s->size);
5677 if (s->contents == NULL && s->size != 0)
5678 return FALSE;
5680 if (dynsymcount != 0)
5682 Elf_Internal_Sym isym;
5684 /* The first entry in .dynsym is a dummy symbol. */
5685 isym.st_value = 0;
5686 isym.st_size = 0;
5687 isym.st_name = 0;
5688 isym.st_info = 0;
5689 isym.st_other = 0;
5690 isym.st_shndx = 0;
5691 bed->s->swap_symbol_out (output_bfd, &isym, s->contents, 0);
5694 /* Compute the size of the hashing table. As a side effect this
5695 computes the hash values for all the names we export. */
5696 bucketcount = compute_bucket_count (info);
5698 s = bfd_get_section_by_name (dynobj, ".hash");
5699 BFD_ASSERT (s != NULL);
5700 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5701 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5702 s->contents = bfd_zalloc (output_bfd, s->size);
5703 if (s->contents == NULL)
5704 return FALSE;
5706 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5707 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5708 s->contents + hash_entry_size);
5710 elf_hash_table (info)->bucketcount = bucketcount;
5712 s = bfd_get_section_by_name (dynobj, ".dynstr");
5713 BFD_ASSERT (s != NULL);
5715 elf_finalize_dynstr (output_bfd, info);
5717 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5719 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5720 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5721 return FALSE;
5724 return TRUE;
5727 /* Final phase of ELF linker. */
5729 /* A structure we use to avoid passing large numbers of arguments. */
5731 struct elf_final_link_info
5733 /* General link information. */
5734 struct bfd_link_info *info;
5735 /* Output BFD. */
5736 bfd *output_bfd;
5737 /* Symbol string table. */
5738 struct bfd_strtab_hash *symstrtab;
5739 /* .dynsym section. */
5740 asection *dynsym_sec;
5741 /* .hash section. */
5742 asection *hash_sec;
5743 /* symbol version section (.gnu.version). */
5744 asection *symver_sec;
5745 /* Buffer large enough to hold contents of any section. */
5746 bfd_byte *contents;
5747 /* Buffer large enough to hold external relocs of any section. */
5748 void *external_relocs;
5749 /* Buffer large enough to hold internal relocs of any section. */
5750 Elf_Internal_Rela *internal_relocs;
5751 /* Buffer large enough to hold external local symbols of any input
5752 BFD. */
5753 bfd_byte *external_syms;
5754 /* And a buffer for symbol section indices. */
5755 Elf_External_Sym_Shndx *locsym_shndx;
5756 /* Buffer large enough to hold internal local symbols of any input
5757 BFD. */
5758 Elf_Internal_Sym *internal_syms;
5759 /* Array large enough to hold a symbol index for each local symbol
5760 of any input BFD. */
5761 long *indices;
5762 /* Array large enough to hold a section pointer for each local
5763 symbol of any input BFD. */
5764 asection **sections;
5765 /* Buffer to hold swapped out symbols. */
5766 bfd_byte *symbuf;
5767 /* And one for symbol section indices. */
5768 Elf_External_Sym_Shndx *symshndxbuf;
5769 /* Number of swapped out symbols in buffer. */
5770 size_t symbuf_count;
5771 /* Number of symbols which fit in symbuf. */
5772 size_t symbuf_size;
5773 /* And same for symshndxbuf. */
5774 size_t shndxbuf_size;
5777 /* This struct is used to pass information to elf_link_output_extsym. */
5779 struct elf_outext_info
5781 bfd_boolean failed;
5782 bfd_boolean localsyms;
5783 struct elf_final_link_info *finfo;
5786 /* When performing a relocatable link, the input relocations are
5787 preserved. But, if they reference global symbols, the indices
5788 referenced must be updated. Update all the relocations in
5789 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5791 static void
5792 elf_link_adjust_relocs (bfd *abfd,
5793 Elf_Internal_Shdr *rel_hdr,
5794 unsigned int count,
5795 struct elf_link_hash_entry **rel_hash)
5797 unsigned int i;
5798 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5799 bfd_byte *erela;
5800 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5801 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5802 bfd_vma r_type_mask;
5803 int r_sym_shift;
5805 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5807 swap_in = bed->s->swap_reloc_in;
5808 swap_out = bed->s->swap_reloc_out;
5810 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5812 swap_in = bed->s->swap_reloca_in;
5813 swap_out = bed->s->swap_reloca_out;
5815 else
5816 abort ();
5818 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5819 abort ();
5821 if (bed->s->arch_size == 32)
5823 r_type_mask = 0xff;
5824 r_sym_shift = 8;
5826 else
5828 r_type_mask = 0xffffffff;
5829 r_sym_shift = 32;
5832 erela = rel_hdr->contents;
5833 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5835 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5836 unsigned int j;
5838 if (*rel_hash == NULL)
5839 continue;
5841 BFD_ASSERT ((*rel_hash)->indx >= 0);
5843 (*swap_in) (abfd, erela, irela);
5844 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5845 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5846 | (irela[j].r_info & r_type_mask));
5847 (*swap_out) (abfd, irela, erela);
5851 struct elf_link_sort_rela
5853 union {
5854 bfd_vma offset;
5855 bfd_vma sym_mask;
5856 } u;
5857 enum elf_reloc_type_class type;
5858 /* We use this as an array of size int_rels_per_ext_rel. */
5859 Elf_Internal_Rela rela[1];
5862 static int
5863 elf_link_sort_cmp1 (const void *A, const void *B)
5865 const struct elf_link_sort_rela *a = A;
5866 const struct elf_link_sort_rela *b = B;
5867 int relativea, relativeb;
5869 relativea = a->type == reloc_class_relative;
5870 relativeb = b->type == reloc_class_relative;
5872 if (relativea < relativeb)
5873 return 1;
5874 if (relativea > relativeb)
5875 return -1;
5876 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5877 return -1;
5878 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5879 return 1;
5880 if (a->rela->r_offset < b->rela->r_offset)
5881 return -1;
5882 if (a->rela->r_offset > b->rela->r_offset)
5883 return 1;
5884 return 0;
5887 static int
5888 elf_link_sort_cmp2 (const void *A, const void *B)
5890 const struct elf_link_sort_rela *a = A;
5891 const struct elf_link_sort_rela *b = B;
5892 int copya, copyb;
5894 if (a->u.offset < b->u.offset)
5895 return -1;
5896 if (a->u.offset > b->u.offset)
5897 return 1;
5898 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5899 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5900 if (copya < copyb)
5901 return -1;
5902 if (copya > copyb)
5903 return 1;
5904 if (a->rela->r_offset < b->rela->r_offset)
5905 return -1;
5906 if (a->rela->r_offset > b->rela->r_offset)
5907 return 1;
5908 return 0;
5911 static size_t
5912 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5914 asection *reldyn;
5915 bfd_size_type count, size;
5916 size_t i, ret, sort_elt, ext_size;
5917 bfd_byte *sort, *s_non_relative, *p;
5918 struct elf_link_sort_rela *sq;
5919 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5920 int i2e = bed->s->int_rels_per_ext_rel;
5921 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5922 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5923 struct bfd_link_order *lo;
5924 bfd_vma r_sym_mask;
5926 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5927 if (reldyn == NULL || reldyn->size == 0)
5929 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
5930 if (reldyn == NULL || reldyn->size == 0)
5931 return 0;
5932 ext_size = bed->s->sizeof_rel;
5933 swap_in = bed->s->swap_reloc_in;
5934 swap_out = bed->s->swap_reloc_out;
5936 else
5938 ext_size = bed->s->sizeof_rela;
5939 swap_in = bed->s->swap_reloca_in;
5940 swap_out = bed->s->swap_reloca_out;
5942 count = reldyn->size / ext_size;
5944 size = 0;
5945 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5946 if (lo->type == bfd_indirect_link_order)
5948 asection *o = lo->u.indirect.section;
5949 size += o->size;
5952 if (size != reldyn->size)
5953 return 0;
5955 sort_elt = (sizeof (struct elf_link_sort_rela)
5956 + (i2e - 1) * sizeof (Elf_Internal_Rela));
5957 sort = bfd_zmalloc (sort_elt * count);
5958 if (sort == NULL)
5960 (*info->callbacks->warning)
5961 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
5962 return 0;
5965 if (bed->s->arch_size == 32)
5966 r_sym_mask = ~(bfd_vma) 0xff;
5967 else
5968 r_sym_mask = ~(bfd_vma) 0xffffffff;
5970 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5971 if (lo->type == bfd_indirect_link_order)
5973 bfd_byte *erel, *erelend;
5974 asection *o = lo->u.indirect.section;
5976 if (o->contents == NULL && o->size != 0)
5978 /* This is a reloc section that is being handled as a normal
5979 section. See bfd_section_from_shdr. We can't combine
5980 relocs in this case. */
5981 free (sort);
5982 return 0;
5984 erel = o->contents;
5985 erelend = o->contents + o->size;
5986 p = sort + o->output_offset / ext_size * sort_elt;
5987 while (erel < erelend)
5989 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5990 (*swap_in) (abfd, erel, s->rela);
5991 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
5992 s->u.sym_mask = r_sym_mask;
5993 p += sort_elt;
5994 erel += ext_size;
5998 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
6000 for (i = 0, p = sort; i < count; i++, p += sort_elt)
6002 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6003 if (s->type != reloc_class_relative)
6004 break;
6006 ret = i;
6007 s_non_relative = p;
6009 sq = (struct elf_link_sort_rela *) s_non_relative;
6010 for (; i < count; i++, p += sort_elt)
6012 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
6013 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
6014 sq = sp;
6015 sp->u.offset = sq->rela->r_offset;
6018 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
6020 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
6021 if (lo->type == bfd_indirect_link_order)
6023 bfd_byte *erel, *erelend;
6024 asection *o = lo->u.indirect.section;
6026 erel = o->contents;
6027 erelend = o->contents + o->size;
6028 p = sort + o->output_offset / ext_size * sort_elt;
6029 while (erel < erelend)
6031 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6032 (*swap_out) (abfd, s->rela, erel);
6033 p += sort_elt;
6034 erel += ext_size;
6038 free (sort);
6039 *psec = reldyn;
6040 return ret;
6043 /* Flush the output symbols to the file. */
6045 static bfd_boolean
6046 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
6047 const struct elf_backend_data *bed)
6049 if (finfo->symbuf_count > 0)
6051 Elf_Internal_Shdr *hdr;
6052 file_ptr pos;
6053 bfd_size_type amt;
6055 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6056 pos = hdr->sh_offset + hdr->sh_size;
6057 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6058 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6059 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6060 return FALSE;
6062 hdr->sh_size += amt;
6063 finfo->symbuf_count = 0;
6066 return TRUE;
6069 /* Add a symbol to the output symbol table. */
6071 static bfd_boolean
6072 elf_link_output_sym (struct elf_final_link_info *finfo,
6073 const char *name,
6074 Elf_Internal_Sym *elfsym,
6075 asection *input_sec,
6076 struct elf_link_hash_entry *h)
6078 bfd_byte *dest;
6079 Elf_External_Sym_Shndx *destshndx;
6080 bfd_boolean (*output_symbol_hook)
6081 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6082 struct elf_link_hash_entry *);
6083 const struct elf_backend_data *bed;
6085 bed = get_elf_backend_data (finfo->output_bfd);
6086 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6087 if (output_symbol_hook != NULL)
6089 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6090 return FALSE;
6093 if (name == NULL || *name == '\0')
6094 elfsym->st_name = 0;
6095 else if (input_sec->flags & SEC_EXCLUDE)
6096 elfsym->st_name = 0;
6097 else
6099 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6100 name, TRUE, FALSE);
6101 if (elfsym->st_name == (unsigned long) -1)
6102 return FALSE;
6105 if (finfo->symbuf_count >= finfo->symbuf_size)
6107 if (! elf_link_flush_output_syms (finfo, bed))
6108 return FALSE;
6111 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6112 destshndx = finfo->symshndxbuf;
6113 if (destshndx != NULL)
6115 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6117 bfd_size_type amt;
6119 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6120 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6121 if (destshndx == NULL)
6122 return FALSE;
6123 memset ((char *) destshndx + amt, 0, amt);
6124 finfo->shndxbuf_size *= 2;
6126 destshndx += bfd_get_symcount (finfo->output_bfd);
6129 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6130 finfo->symbuf_count += 1;
6131 bfd_get_symcount (finfo->output_bfd) += 1;
6133 return TRUE;
6136 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6137 allowing an unsatisfied unversioned symbol in the DSO to match a
6138 versioned symbol that would normally require an explicit version.
6139 We also handle the case that a DSO references a hidden symbol
6140 which may be satisfied by a versioned symbol in another DSO. */
6142 static bfd_boolean
6143 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6144 const struct elf_backend_data *bed,
6145 struct elf_link_hash_entry *h)
6147 bfd *abfd;
6148 struct elf_link_loaded_list *loaded;
6150 if (!is_elf_hash_table (info->hash))
6151 return FALSE;
6153 switch (h->root.type)
6155 default:
6156 abfd = NULL;
6157 break;
6159 case bfd_link_hash_undefined:
6160 case bfd_link_hash_undefweak:
6161 abfd = h->root.u.undef.abfd;
6162 if ((abfd->flags & DYNAMIC) == 0
6163 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6164 return FALSE;
6165 break;
6167 case bfd_link_hash_defined:
6168 case bfd_link_hash_defweak:
6169 abfd = h->root.u.def.section->owner;
6170 break;
6172 case bfd_link_hash_common:
6173 abfd = h->root.u.c.p->section->owner;
6174 break;
6176 BFD_ASSERT (abfd != NULL);
6178 for (loaded = elf_hash_table (info)->loaded;
6179 loaded != NULL;
6180 loaded = loaded->next)
6182 bfd *input;
6183 Elf_Internal_Shdr *hdr;
6184 bfd_size_type symcount;
6185 bfd_size_type extsymcount;
6186 bfd_size_type extsymoff;
6187 Elf_Internal_Shdr *versymhdr;
6188 Elf_Internal_Sym *isym;
6189 Elf_Internal_Sym *isymend;
6190 Elf_Internal_Sym *isymbuf;
6191 Elf_External_Versym *ever;
6192 Elf_External_Versym *extversym;
6194 input = loaded->abfd;
6196 /* We check each DSO for a possible hidden versioned definition. */
6197 if (input == abfd
6198 || (input->flags & DYNAMIC) == 0
6199 || elf_dynversym (input) == 0)
6200 continue;
6202 hdr = &elf_tdata (input)->dynsymtab_hdr;
6204 symcount = hdr->sh_size / bed->s->sizeof_sym;
6205 if (elf_bad_symtab (input))
6207 extsymcount = symcount;
6208 extsymoff = 0;
6210 else
6212 extsymcount = symcount - hdr->sh_info;
6213 extsymoff = hdr->sh_info;
6216 if (extsymcount == 0)
6217 continue;
6219 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6220 NULL, NULL, NULL);
6221 if (isymbuf == NULL)
6222 return FALSE;
6224 /* Read in any version definitions. */
6225 versymhdr = &elf_tdata (input)->dynversym_hdr;
6226 extversym = bfd_malloc (versymhdr->sh_size);
6227 if (extversym == NULL)
6228 goto error_ret;
6230 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6231 || (bfd_bread (extversym, versymhdr->sh_size, input)
6232 != versymhdr->sh_size))
6234 free (extversym);
6235 error_ret:
6236 free (isymbuf);
6237 return FALSE;
6240 ever = extversym + extsymoff;
6241 isymend = isymbuf + extsymcount;
6242 for (isym = isymbuf; isym < isymend; isym++, ever++)
6244 const char *name;
6245 Elf_Internal_Versym iver;
6246 unsigned short version_index;
6248 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6249 || isym->st_shndx == SHN_UNDEF)
6250 continue;
6252 name = bfd_elf_string_from_elf_section (input,
6253 hdr->sh_link,
6254 isym->st_name);
6255 if (strcmp (name, h->root.root.string) != 0)
6256 continue;
6258 _bfd_elf_swap_versym_in (input, ever, &iver);
6260 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6262 /* If we have a non-hidden versioned sym, then it should
6263 have provided a definition for the undefined sym. */
6264 abort ();
6267 version_index = iver.vs_vers & VERSYM_VERSION;
6268 if (version_index == 1 || version_index == 2)
6270 /* This is the base or first version. We can use it. */
6271 free (extversym);
6272 free (isymbuf);
6273 return TRUE;
6277 free (extversym);
6278 free (isymbuf);
6281 return FALSE;
6284 /* Add an external symbol to the symbol table. This is called from
6285 the hash table traversal routine. When generating a shared object,
6286 we go through the symbol table twice. The first time we output
6287 anything that might have been forced to local scope in a version
6288 script. The second time we output the symbols that are still
6289 global symbols. */
6291 static bfd_boolean
6292 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6294 struct elf_outext_info *eoinfo = data;
6295 struct elf_final_link_info *finfo = eoinfo->finfo;
6296 bfd_boolean strip;
6297 Elf_Internal_Sym sym;
6298 asection *input_sec;
6299 const struct elf_backend_data *bed;
6301 if (h->root.type == bfd_link_hash_warning)
6303 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6304 if (h->root.type == bfd_link_hash_new)
6305 return TRUE;
6308 /* Decide whether to output this symbol in this pass. */
6309 if (eoinfo->localsyms)
6311 if (!h->forced_local)
6312 return TRUE;
6314 else
6316 if (h->forced_local)
6317 return TRUE;
6320 bed = get_elf_backend_data (finfo->output_bfd);
6322 /* If we have an undefined symbol reference here then it must have
6323 come from a shared library that is being linked in. (Undefined
6324 references in regular files have already been handled). If we
6325 are reporting errors for this situation then do so now. */
6326 if (h->root.type == bfd_link_hash_undefined
6327 && h->ref_dynamic
6328 && !h->ref_regular
6329 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6330 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6332 if (! ((*finfo->info->callbacks->undefined_symbol)
6333 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6334 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6336 eoinfo->failed = TRUE;
6337 return FALSE;
6341 /* We should also warn if a forced local symbol is referenced from
6342 shared libraries. */
6343 if (! finfo->info->relocatable
6344 && (! finfo->info->shared)
6345 && h->forced_local
6346 && h->ref_dynamic
6347 && !h->dynamic_def
6348 && !h->dynamic_weak
6349 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6351 (*_bfd_error_handler)
6352 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6353 finfo->output_bfd, h->root.u.def.section->owner,
6354 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6355 ? "internal"
6356 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6357 ? "hidden" : "local",
6358 h->root.root.string);
6359 eoinfo->failed = TRUE;
6360 return FALSE;
6363 /* We don't want to output symbols that have never been mentioned by
6364 a regular file, or that we have been told to strip. However, if
6365 h->indx is set to -2, the symbol is used by a reloc and we must
6366 output it. */
6367 if (h->indx == -2)
6368 strip = FALSE;
6369 else if ((h->def_dynamic
6370 || h->ref_dynamic
6371 || h->root.type == bfd_link_hash_new)
6372 && !h->def_regular
6373 && !h->ref_regular)
6374 strip = TRUE;
6375 else if (finfo->info->strip == strip_all)
6376 strip = TRUE;
6377 else if (finfo->info->strip == strip_some
6378 && bfd_hash_lookup (finfo->info->keep_hash,
6379 h->root.root.string, FALSE, FALSE) == NULL)
6380 strip = TRUE;
6381 else if (finfo->info->strip_discarded
6382 && (h->root.type == bfd_link_hash_defined
6383 || h->root.type == bfd_link_hash_defweak)
6384 && elf_discarded_section (h->root.u.def.section))
6385 strip = TRUE;
6386 else
6387 strip = FALSE;
6389 /* If we're stripping it, and it's not a dynamic symbol, there's
6390 nothing else to do unless it is a forced local symbol. */
6391 if (strip
6392 && h->dynindx == -1
6393 && !h->forced_local)
6394 return TRUE;
6396 sym.st_value = 0;
6397 sym.st_size = h->size;
6398 sym.st_other = h->other;
6399 if (h->forced_local)
6400 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6401 else if (h->root.type == bfd_link_hash_undefweak
6402 || h->root.type == bfd_link_hash_defweak)
6403 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6404 else
6405 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6407 switch (h->root.type)
6409 default:
6410 case bfd_link_hash_new:
6411 case bfd_link_hash_warning:
6412 abort ();
6413 return FALSE;
6415 case bfd_link_hash_undefined:
6416 case bfd_link_hash_undefweak:
6417 input_sec = bfd_und_section_ptr;
6418 sym.st_shndx = SHN_UNDEF;
6419 break;
6421 case bfd_link_hash_defined:
6422 case bfd_link_hash_defweak:
6424 input_sec = h->root.u.def.section;
6425 if (input_sec->output_section != NULL)
6427 sym.st_shndx =
6428 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6429 input_sec->output_section);
6430 if (sym.st_shndx == SHN_BAD)
6432 (*_bfd_error_handler)
6433 (_("%B: could not find output section %A for input section %A"),
6434 finfo->output_bfd, input_sec->output_section, input_sec);
6435 eoinfo->failed = TRUE;
6436 return FALSE;
6439 /* ELF symbols in relocatable files are section relative,
6440 but in nonrelocatable files they are virtual
6441 addresses. */
6442 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6443 if (! finfo->info->relocatable)
6445 sym.st_value += input_sec->output_section->vma;
6446 if (h->type == STT_TLS)
6448 /* STT_TLS symbols are relative to PT_TLS segment
6449 base. */
6450 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6451 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6455 else
6457 BFD_ASSERT (input_sec->owner == NULL
6458 || (input_sec->owner->flags & DYNAMIC) != 0);
6459 sym.st_shndx = SHN_UNDEF;
6460 input_sec = bfd_und_section_ptr;
6463 break;
6465 case bfd_link_hash_common:
6466 input_sec = h->root.u.c.p->section;
6467 sym.st_shndx = SHN_COMMON;
6468 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6469 break;
6471 case bfd_link_hash_indirect:
6472 /* These symbols are created by symbol versioning. They point
6473 to the decorated version of the name. For example, if the
6474 symbol foo@@GNU_1.2 is the default, which should be used when
6475 foo is used with no version, then we add an indirect symbol
6476 foo which points to foo@@GNU_1.2. We ignore these symbols,
6477 since the indirected symbol is already in the hash table. */
6478 return TRUE;
6481 /* Give the processor backend a chance to tweak the symbol value,
6482 and also to finish up anything that needs to be done for this
6483 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6484 forced local syms when non-shared is due to a historical quirk. */
6485 if ((h->dynindx != -1
6486 || h->forced_local)
6487 && ((finfo->info->shared
6488 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6489 || h->root.type != bfd_link_hash_undefweak))
6490 || !h->forced_local)
6491 && elf_hash_table (finfo->info)->dynamic_sections_created)
6493 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6494 (finfo->output_bfd, finfo->info, h, &sym)))
6496 eoinfo->failed = TRUE;
6497 return FALSE;
6501 /* If we are marking the symbol as undefined, and there are no
6502 non-weak references to this symbol from a regular object, then
6503 mark the symbol as weak undefined; if there are non-weak
6504 references, mark the symbol as strong. We can't do this earlier,
6505 because it might not be marked as undefined until the
6506 finish_dynamic_symbol routine gets through with it. */
6507 if (sym.st_shndx == SHN_UNDEF
6508 && h->ref_regular
6509 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6510 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6512 int bindtype;
6514 if (h->ref_regular_nonweak)
6515 bindtype = STB_GLOBAL;
6516 else
6517 bindtype = STB_WEAK;
6518 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6521 /* If a non-weak symbol with non-default visibility is not defined
6522 locally, it is a fatal error. */
6523 if (! finfo->info->relocatable
6524 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6525 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6526 && h->root.type == bfd_link_hash_undefined
6527 && !h->def_regular)
6529 (*_bfd_error_handler)
6530 (_("%B: %s symbol `%s' isn't defined"),
6531 finfo->output_bfd,
6532 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6533 ? "protected"
6534 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6535 ? "internal" : "hidden",
6536 h->root.root.string);
6537 eoinfo->failed = TRUE;
6538 return FALSE;
6541 /* If this symbol should be put in the .dynsym section, then put it
6542 there now. We already know the symbol index. We also fill in
6543 the entry in the .hash section. */
6544 if (h->dynindx != -1
6545 && elf_hash_table (finfo->info)->dynamic_sections_created)
6547 size_t bucketcount;
6548 size_t bucket;
6549 size_t hash_entry_size;
6550 bfd_byte *bucketpos;
6551 bfd_vma chain;
6552 bfd_byte *esym;
6554 sym.st_name = h->dynstr_index;
6555 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6556 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6558 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6559 bucket = h->u.elf_hash_value % bucketcount;
6560 hash_entry_size
6561 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6562 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6563 + (bucket + 2) * hash_entry_size);
6564 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6565 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6566 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6567 ((bfd_byte *) finfo->hash_sec->contents
6568 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6570 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6572 Elf_Internal_Versym iversym;
6573 Elf_External_Versym *eversym;
6575 if (!h->def_regular)
6577 if (h->verinfo.verdef == NULL)
6578 iversym.vs_vers = 0;
6579 else
6580 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6582 else
6584 if (h->verinfo.vertree == NULL)
6585 iversym.vs_vers = 1;
6586 else
6587 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6588 if (finfo->info->create_default_symver)
6589 iversym.vs_vers++;
6592 if (h->hidden)
6593 iversym.vs_vers |= VERSYM_HIDDEN;
6595 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6596 eversym += h->dynindx;
6597 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6601 /* If we're stripping it, then it was just a dynamic symbol, and
6602 there's nothing else to do. */
6603 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6604 return TRUE;
6606 h->indx = bfd_get_symcount (finfo->output_bfd);
6608 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6610 eoinfo->failed = TRUE;
6611 return FALSE;
6614 return TRUE;
6617 /* Return TRUE if special handling is done for relocs in SEC against
6618 symbols defined in discarded sections. */
6620 static bfd_boolean
6621 elf_section_ignore_discarded_relocs (asection *sec)
6623 const struct elf_backend_data *bed;
6625 switch (sec->sec_info_type)
6627 case ELF_INFO_TYPE_STABS:
6628 case ELF_INFO_TYPE_EH_FRAME:
6629 return TRUE;
6630 default:
6631 break;
6634 bed = get_elf_backend_data (sec->owner);
6635 if (bed->elf_backend_ignore_discarded_relocs != NULL
6636 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6637 return TRUE;
6639 return FALSE;
6642 enum action_discarded
6644 COMPLAIN = 1,
6645 PRETEND = 2
6648 /* Return a mask saying how ld should treat relocations in SEC against
6649 symbols defined in discarded sections. If this function returns
6650 COMPLAIN set, ld will issue a warning message. If this function
6651 returns PRETEND set, and the discarded section was link-once and the
6652 same size as the kept link-once section, ld will pretend that the
6653 symbol was actually defined in the kept section. Otherwise ld will
6654 zero the reloc (at least that is the intent, but some cooperation by
6655 the target dependent code is needed, particularly for REL targets). */
6657 static unsigned int
6658 elf_action_discarded (asection *sec)
6660 if (sec->flags & SEC_DEBUGGING)
6661 return PRETEND;
6663 if (strcmp (".eh_frame", sec->name) == 0)
6664 return 0;
6666 if (strcmp (".gcc_except_table", sec->name) == 0)
6667 return 0;
6669 if (strcmp (".PARISC.unwind", sec->name) == 0)
6670 return 0;
6672 if (strcmp (".fixup", sec->name) == 0)
6673 return 0;
6675 return COMPLAIN | PRETEND;
6678 /* Find a match between a section and a member of a section group. */
6680 static asection *
6681 match_group_member (asection *sec, asection *group)
6683 asection *first = elf_next_in_group (group);
6684 asection *s = first;
6686 while (s != NULL)
6688 if (bfd_elf_match_symbols_in_sections (s, sec))
6689 return s;
6691 if (s == first)
6692 break;
6695 return NULL;
6698 /* Link an input file into the linker output file. This function
6699 handles all the sections and relocations of the input file at once.
6700 This is so that we only have to read the local symbols once, and
6701 don't have to keep them in memory. */
6703 static bfd_boolean
6704 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6706 bfd_boolean (*relocate_section)
6707 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6708 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6709 bfd *output_bfd;
6710 Elf_Internal_Shdr *symtab_hdr;
6711 size_t locsymcount;
6712 size_t extsymoff;
6713 Elf_Internal_Sym *isymbuf;
6714 Elf_Internal_Sym *isym;
6715 Elf_Internal_Sym *isymend;
6716 long *pindex;
6717 asection **ppsection;
6718 asection *o;
6719 const struct elf_backend_data *bed;
6720 bfd_boolean emit_relocs;
6721 struct elf_link_hash_entry **sym_hashes;
6723 output_bfd = finfo->output_bfd;
6724 bed = get_elf_backend_data (output_bfd);
6725 relocate_section = bed->elf_backend_relocate_section;
6727 /* If this is a dynamic object, we don't want to do anything here:
6728 we don't want the local symbols, and we don't want the section
6729 contents. */
6730 if ((input_bfd->flags & DYNAMIC) != 0)
6731 return TRUE;
6733 emit_relocs = (finfo->info->relocatable
6734 || finfo->info->emitrelocations
6735 || bed->elf_backend_emit_relocs);
6737 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6738 if (elf_bad_symtab (input_bfd))
6740 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6741 extsymoff = 0;
6743 else
6745 locsymcount = symtab_hdr->sh_info;
6746 extsymoff = symtab_hdr->sh_info;
6749 /* Read the local symbols. */
6750 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6751 if (isymbuf == NULL && locsymcount != 0)
6753 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6754 finfo->internal_syms,
6755 finfo->external_syms,
6756 finfo->locsym_shndx);
6757 if (isymbuf == NULL)
6758 return FALSE;
6761 /* Find local symbol sections and adjust values of symbols in
6762 SEC_MERGE sections. Write out those local symbols we know are
6763 going into the output file. */
6764 isymend = isymbuf + locsymcount;
6765 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6766 isym < isymend;
6767 isym++, pindex++, ppsection++)
6769 asection *isec;
6770 const char *name;
6771 Elf_Internal_Sym osym;
6773 *pindex = -1;
6775 if (elf_bad_symtab (input_bfd))
6777 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6779 *ppsection = NULL;
6780 continue;
6784 if (isym->st_shndx == SHN_UNDEF)
6785 isec = bfd_und_section_ptr;
6786 else if (isym->st_shndx < SHN_LORESERVE
6787 || isym->st_shndx > SHN_HIRESERVE)
6789 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6790 if (isec
6791 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6792 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6793 isym->st_value =
6794 _bfd_merged_section_offset (output_bfd, &isec,
6795 elf_section_data (isec)->sec_info,
6796 isym->st_value);
6798 else if (isym->st_shndx == SHN_ABS)
6799 isec = bfd_abs_section_ptr;
6800 else if (isym->st_shndx == SHN_COMMON)
6801 isec = bfd_com_section_ptr;
6802 else
6804 /* Who knows? */
6805 isec = NULL;
6808 *ppsection = isec;
6810 /* Don't output the first, undefined, symbol. */
6811 if (ppsection == finfo->sections)
6812 continue;
6814 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6816 /* We never output section symbols. Instead, we use the
6817 section symbol of the corresponding section in the output
6818 file. */
6819 continue;
6822 /* If we are stripping all symbols, we don't want to output this
6823 one. */
6824 if (finfo->info->strip == strip_all)
6825 continue;
6827 /* If we are discarding all local symbols, we don't want to
6828 output this one. If we are generating a relocatable output
6829 file, then some of the local symbols may be required by
6830 relocs; we output them below as we discover that they are
6831 needed. */
6832 if (finfo->info->discard == discard_all)
6833 continue;
6835 /* If this symbol is defined in a section which we are
6836 discarding, we don't need to keep it, but note that
6837 linker_mark is only reliable for sections that have contents.
6838 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
6839 as well as linker_mark. */
6840 if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6841 && (isec == NULL
6842 || (! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
6843 || (! finfo->info->relocatable
6844 && (isec->flags & SEC_EXCLUDE) != 0)))
6845 continue;
6847 /* Get the name of the symbol. */
6848 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6849 isym->st_name);
6850 if (name == NULL)
6851 return FALSE;
6853 /* See if we are discarding symbols with this name. */
6854 if ((finfo->info->strip == strip_some
6855 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6856 == NULL))
6857 || (((finfo->info->discard == discard_sec_merge
6858 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6859 || finfo->info->discard == discard_l)
6860 && bfd_is_local_label_name (input_bfd, name)))
6861 continue;
6863 /* If we get here, we are going to output this symbol. */
6865 osym = *isym;
6867 /* Adjust the section index for the output file. */
6868 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6869 isec->output_section);
6870 if (osym.st_shndx == SHN_BAD)
6871 return FALSE;
6873 *pindex = bfd_get_symcount (output_bfd);
6875 /* ELF symbols in relocatable files are section relative, but
6876 in executable files they are virtual addresses. Note that
6877 this code assumes that all ELF sections have an associated
6878 BFD section with a reasonable value for output_offset; below
6879 we assume that they also have a reasonable value for
6880 output_section. Any special sections must be set up to meet
6881 these requirements. */
6882 osym.st_value += isec->output_offset;
6883 if (! finfo->info->relocatable)
6885 osym.st_value += isec->output_section->vma;
6886 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
6888 /* STT_TLS symbols are relative to PT_TLS segment base. */
6889 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6890 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6894 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
6895 return FALSE;
6898 /* Relocate the contents of each section. */
6899 sym_hashes = elf_sym_hashes (input_bfd);
6900 for (o = input_bfd->sections; o != NULL; o = o->next)
6902 bfd_byte *contents;
6904 if (! o->linker_mark)
6906 /* This section was omitted from the link. */
6907 continue;
6910 if ((o->flags & SEC_HAS_CONTENTS) == 0
6911 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
6912 continue;
6914 if ((o->flags & SEC_LINKER_CREATED) != 0)
6916 /* Section was created by _bfd_elf_link_create_dynamic_sections
6917 or somesuch. */
6918 continue;
6921 /* Get the contents of the section. They have been cached by a
6922 relaxation routine. Note that o is a section in an input
6923 file, so the contents field will not have been set by any of
6924 the routines which work on output files. */
6925 if (elf_section_data (o)->this_hdr.contents != NULL)
6926 contents = elf_section_data (o)->this_hdr.contents;
6927 else
6929 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
6931 contents = finfo->contents;
6932 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
6933 return FALSE;
6936 if ((o->flags & SEC_RELOC) != 0)
6938 Elf_Internal_Rela *internal_relocs;
6939 bfd_vma r_type_mask;
6940 int r_sym_shift;
6942 /* Get the swapped relocs. */
6943 internal_relocs
6944 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
6945 finfo->internal_relocs, FALSE);
6946 if (internal_relocs == NULL
6947 && o->reloc_count > 0)
6948 return FALSE;
6950 if (bed->s->arch_size == 32)
6952 r_type_mask = 0xff;
6953 r_sym_shift = 8;
6955 else
6957 r_type_mask = 0xffffffff;
6958 r_sym_shift = 32;
6961 /* Run through the relocs looking for any against symbols
6962 from discarded sections and section symbols from
6963 removed link-once sections. Complain about relocs
6964 against discarded sections. Zero relocs against removed
6965 link-once sections. Preserve debug information as much
6966 as we can. */
6967 if (!elf_section_ignore_discarded_relocs (o))
6969 Elf_Internal_Rela *rel, *relend;
6970 unsigned int action = elf_action_discarded (o);
6972 rel = internal_relocs;
6973 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
6974 for ( ; rel < relend; rel++)
6976 unsigned long r_symndx = rel->r_info >> r_sym_shift;
6977 asection **ps, *sec;
6978 struct elf_link_hash_entry *h = NULL;
6979 const char *sym_name;
6981 if (r_symndx == STN_UNDEF)
6982 continue;
6984 if (r_symndx >= locsymcount
6985 || (elf_bad_symtab (input_bfd)
6986 && finfo->sections[r_symndx] == NULL))
6988 h = sym_hashes[r_symndx - extsymoff];
6989 while (h->root.type == bfd_link_hash_indirect
6990 || h->root.type == bfd_link_hash_warning)
6991 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6993 if (h->root.type != bfd_link_hash_defined
6994 && h->root.type != bfd_link_hash_defweak)
6995 continue;
6997 ps = &h->root.u.def.section;
6998 sym_name = h->root.root.string;
7000 else
7002 Elf_Internal_Sym *sym = isymbuf + r_symndx;
7003 ps = &finfo->sections[r_symndx];
7004 sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym);
7007 /* Complain if the definition comes from a
7008 discarded section. */
7009 if ((sec = *ps) != NULL && elf_discarded_section (sec))
7011 asection *kept;
7013 BFD_ASSERT (r_symndx != 0);
7014 if (action & COMPLAIN)
7016 (*_bfd_error_handler)
7017 (_("`%s' referenced in section `%A' of %B: "
7018 "defined in discarded section `%A' of %B\n"),
7019 o, input_bfd, sec, sec->owner, sym_name);
7022 /* Try to do the best we can to support buggy old
7023 versions of gcc. If we've warned, or this is
7024 debugging info, pretend that the symbol is
7025 really defined in the kept linkonce section.
7026 FIXME: This is quite broken. Modifying the
7027 symbol here means we will be changing all later
7028 uses of the symbol, not just in this section.
7029 The only thing that makes this half reasonable
7030 is that we warn in non-debug sections, and
7031 debug sections tend to come after other
7032 sections. */
7033 kept = sec->kept_section;
7034 if (kept != NULL && (action & PRETEND))
7036 if (elf_sec_group (sec) != NULL)
7037 kept = match_group_member (sec, kept);
7038 if (kept != NULL
7039 && sec->size == kept->size)
7041 *ps = kept;
7042 continue;
7046 /* Remove the symbol reference from the reloc, but
7047 don't kill the reloc completely. This is so that
7048 a zero value will be written into the section,
7049 which may have non-zero contents put there by the
7050 assembler. Zero in things like an eh_frame fde
7051 pc_begin allows stack unwinders to recognize the
7052 fde as bogus. */
7053 rel->r_info &= r_type_mask;
7054 rel->r_addend = 0;
7059 /* Relocate the section by invoking a back end routine.
7061 The back end routine is responsible for adjusting the
7062 section contents as necessary, and (if using Rela relocs
7063 and generating a relocatable output file) adjusting the
7064 reloc addend as necessary.
7066 The back end routine does not have to worry about setting
7067 the reloc address or the reloc symbol index.
7069 The back end routine is given a pointer to the swapped in
7070 internal symbols, and can access the hash table entries
7071 for the external symbols via elf_sym_hashes (input_bfd).
7073 When generating relocatable output, the back end routine
7074 must handle STB_LOCAL/STT_SECTION symbols specially. The
7075 output symbol is going to be a section symbol
7076 corresponding to the output section, which will require
7077 the addend to be adjusted. */
7079 if (! (*relocate_section) (output_bfd, finfo->info,
7080 input_bfd, o, contents,
7081 internal_relocs,
7082 isymbuf,
7083 finfo->sections))
7084 return FALSE;
7086 if (emit_relocs)
7088 Elf_Internal_Rela *irela;
7089 Elf_Internal_Rela *irelaend;
7090 bfd_vma last_offset;
7091 struct elf_link_hash_entry **rel_hash;
7092 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7093 unsigned int next_erel;
7094 bfd_boolean (*reloc_emitter)
7095 (bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *);
7096 bfd_boolean rela_normal;
7098 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7099 rela_normal = (bed->rela_normal
7100 && (input_rel_hdr->sh_entsize
7101 == bed->s->sizeof_rela));
7103 /* Adjust the reloc addresses and symbol indices. */
7105 irela = internal_relocs;
7106 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7107 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7108 + elf_section_data (o->output_section)->rel_count
7109 + elf_section_data (o->output_section)->rel_count2);
7110 last_offset = o->output_offset;
7111 if (!finfo->info->relocatable)
7112 last_offset += o->output_section->vma;
7113 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7115 unsigned long r_symndx;
7116 asection *sec;
7117 Elf_Internal_Sym sym;
7119 if (next_erel == bed->s->int_rels_per_ext_rel)
7121 rel_hash++;
7122 next_erel = 0;
7125 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7126 finfo->info, o,
7127 irela->r_offset);
7128 if (irela->r_offset >= (bfd_vma) -2)
7130 /* This is a reloc for a deleted entry or somesuch.
7131 Turn it into an R_*_NONE reloc, at the same
7132 offset as the last reloc. elf_eh_frame.c and
7133 elf_bfd_discard_info rely on reloc offsets
7134 being ordered. */
7135 irela->r_offset = last_offset;
7136 irela->r_info = 0;
7137 irela->r_addend = 0;
7138 continue;
7141 irela->r_offset += o->output_offset;
7143 /* Relocs in an executable have to be virtual addresses. */
7144 if (!finfo->info->relocatable)
7145 irela->r_offset += o->output_section->vma;
7147 last_offset = irela->r_offset;
7149 r_symndx = irela->r_info >> r_sym_shift;
7150 if (r_symndx == STN_UNDEF)
7151 continue;
7153 if (r_symndx >= locsymcount
7154 || (elf_bad_symtab (input_bfd)
7155 && finfo->sections[r_symndx] == NULL))
7157 struct elf_link_hash_entry *rh;
7158 unsigned long indx;
7160 /* This is a reloc against a global symbol. We
7161 have not yet output all the local symbols, so
7162 we do not know the symbol index of any global
7163 symbol. We set the rel_hash entry for this
7164 reloc to point to the global hash table entry
7165 for this symbol. The symbol index is then
7166 set at the end of bfd_elf_final_link. */
7167 indx = r_symndx - extsymoff;
7168 rh = elf_sym_hashes (input_bfd)[indx];
7169 while (rh->root.type == bfd_link_hash_indirect
7170 || rh->root.type == bfd_link_hash_warning)
7171 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7173 /* Setting the index to -2 tells
7174 elf_link_output_extsym that this symbol is
7175 used by a reloc. */
7176 BFD_ASSERT (rh->indx < 0);
7177 rh->indx = -2;
7179 *rel_hash = rh;
7181 continue;
7184 /* This is a reloc against a local symbol. */
7186 *rel_hash = NULL;
7187 sym = isymbuf[r_symndx];
7188 sec = finfo->sections[r_symndx];
7189 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7191 /* I suppose the backend ought to fill in the
7192 section of any STT_SECTION symbol against a
7193 processor specific section. */
7194 r_symndx = 0;
7195 if (bfd_is_abs_section (sec))
7197 else if (sec == NULL || sec->owner == NULL)
7199 bfd_set_error (bfd_error_bad_value);
7200 return FALSE;
7202 else
7204 asection *osec = sec->output_section;
7206 /* If we have discarded a section, the output
7207 section will be the absolute section. In
7208 case of discarded link-once and discarded
7209 SEC_MERGE sections, use the kept section. */
7210 if (bfd_is_abs_section (osec)
7211 && sec->kept_section != NULL
7212 && sec->kept_section->output_section != NULL)
7214 osec = sec->kept_section->output_section;
7215 irela->r_addend -= osec->vma;
7218 if (!bfd_is_abs_section (osec))
7220 r_symndx = osec->target_index;
7221 BFD_ASSERT (r_symndx != 0);
7225 /* Adjust the addend according to where the
7226 section winds up in the output section. */
7227 if (rela_normal)
7228 irela->r_addend += sec->output_offset;
7230 else
7232 if (finfo->indices[r_symndx] == -1)
7234 unsigned long shlink;
7235 const char *name;
7236 asection *osec;
7238 if (finfo->info->strip == strip_all)
7240 /* You can't do ld -r -s. */
7241 bfd_set_error (bfd_error_invalid_operation);
7242 return FALSE;
7245 /* This symbol was skipped earlier, but
7246 since it is needed by a reloc, we
7247 must output it now. */
7248 shlink = symtab_hdr->sh_link;
7249 name = (bfd_elf_string_from_elf_section
7250 (input_bfd, shlink, sym.st_name));
7251 if (name == NULL)
7252 return FALSE;
7254 osec = sec->output_section;
7255 sym.st_shndx =
7256 _bfd_elf_section_from_bfd_section (output_bfd,
7257 osec);
7258 if (sym.st_shndx == SHN_BAD)
7259 return FALSE;
7261 sym.st_value += sec->output_offset;
7262 if (! finfo->info->relocatable)
7264 sym.st_value += osec->vma;
7265 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7267 /* STT_TLS symbols are relative to PT_TLS
7268 segment base. */
7269 BFD_ASSERT (elf_hash_table (finfo->info)
7270 ->tls_sec != NULL);
7271 sym.st_value -= (elf_hash_table (finfo->info)
7272 ->tls_sec->vma);
7276 finfo->indices[r_symndx]
7277 = bfd_get_symcount (output_bfd);
7279 if (! elf_link_output_sym (finfo, name, &sym, sec,
7280 NULL))
7281 return FALSE;
7284 r_symndx = finfo->indices[r_symndx];
7287 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7288 | (irela->r_info & r_type_mask));
7291 /* Swap out the relocs. */
7292 if (bed->elf_backend_emit_relocs
7293 && !(finfo->info->relocatable
7294 || finfo->info->emitrelocations))
7295 reloc_emitter = bed->elf_backend_emit_relocs;
7296 else
7297 reloc_emitter = _bfd_elf_link_output_relocs;
7299 if (input_rel_hdr->sh_size != 0
7300 && ! (*reloc_emitter) (output_bfd, o, input_rel_hdr,
7301 internal_relocs))
7302 return FALSE;
7304 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7305 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7307 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7308 * bed->s->int_rels_per_ext_rel);
7309 if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2,
7310 internal_relocs))
7311 return FALSE;
7316 /* Write out the modified section contents. */
7317 if (bed->elf_backend_write_section
7318 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7320 /* Section written out. */
7322 else switch (o->sec_info_type)
7324 case ELF_INFO_TYPE_STABS:
7325 if (! (_bfd_write_section_stabs
7326 (output_bfd,
7327 &elf_hash_table (finfo->info)->stab_info,
7328 o, &elf_section_data (o)->sec_info, contents)))
7329 return FALSE;
7330 break;
7331 case ELF_INFO_TYPE_MERGE:
7332 if (! _bfd_write_merged_section (output_bfd, o,
7333 elf_section_data (o)->sec_info))
7334 return FALSE;
7335 break;
7336 case ELF_INFO_TYPE_EH_FRAME:
7338 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7339 o, contents))
7340 return FALSE;
7342 break;
7343 default:
7345 if (! (o->flags & SEC_EXCLUDE)
7346 && ! bfd_set_section_contents (output_bfd, o->output_section,
7347 contents,
7348 (file_ptr) o->output_offset,
7349 o->size))
7350 return FALSE;
7352 break;
7356 return TRUE;
7359 /* Generate a reloc when linking an ELF file. This is a reloc
7360 requested by the linker, and does come from any input file. This
7361 is used to build constructor and destructor tables when linking
7362 with -Ur. */
7364 static bfd_boolean
7365 elf_reloc_link_order (bfd *output_bfd,
7366 struct bfd_link_info *info,
7367 asection *output_section,
7368 struct bfd_link_order *link_order)
7370 reloc_howto_type *howto;
7371 long indx;
7372 bfd_vma offset;
7373 bfd_vma addend;
7374 struct elf_link_hash_entry **rel_hash_ptr;
7375 Elf_Internal_Shdr *rel_hdr;
7376 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7377 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7378 bfd_byte *erel;
7379 unsigned int i;
7381 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7382 if (howto == NULL)
7384 bfd_set_error (bfd_error_bad_value);
7385 return FALSE;
7388 addend = link_order->u.reloc.p->addend;
7390 /* Figure out the symbol index. */
7391 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7392 + elf_section_data (output_section)->rel_count
7393 + elf_section_data (output_section)->rel_count2);
7394 if (link_order->type == bfd_section_reloc_link_order)
7396 indx = link_order->u.reloc.p->u.section->target_index;
7397 BFD_ASSERT (indx != 0);
7398 *rel_hash_ptr = NULL;
7400 else
7402 struct elf_link_hash_entry *h;
7404 /* Treat a reloc against a defined symbol as though it were
7405 actually against the section. */
7406 h = ((struct elf_link_hash_entry *)
7407 bfd_wrapped_link_hash_lookup (output_bfd, info,
7408 link_order->u.reloc.p->u.name,
7409 FALSE, FALSE, TRUE));
7410 if (h != NULL
7411 && (h->root.type == bfd_link_hash_defined
7412 || h->root.type == bfd_link_hash_defweak))
7414 asection *section;
7416 section = h->root.u.def.section;
7417 indx = section->output_section->target_index;
7418 *rel_hash_ptr = NULL;
7419 /* It seems that we ought to add the symbol value to the
7420 addend here, but in practice it has already been added
7421 because it was passed to constructor_callback. */
7422 addend += section->output_section->vma + section->output_offset;
7424 else if (h != NULL)
7426 /* Setting the index to -2 tells elf_link_output_extsym that
7427 this symbol is used by a reloc. */
7428 h->indx = -2;
7429 *rel_hash_ptr = h;
7430 indx = 0;
7432 else
7434 if (! ((*info->callbacks->unattached_reloc)
7435 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7436 return FALSE;
7437 indx = 0;
7441 /* If this is an inplace reloc, we must write the addend into the
7442 object file. */
7443 if (howto->partial_inplace && addend != 0)
7445 bfd_size_type size;
7446 bfd_reloc_status_type rstat;
7447 bfd_byte *buf;
7448 bfd_boolean ok;
7449 const char *sym_name;
7451 size = bfd_get_reloc_size (howto);
7452 buf = bfd_zmalloc (size);
7453 if (buf == NULL)
7454 return FALSE;
7455 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7456 switch (rstat)
7458 case bfd_reloc_ok:
7459 break;
7461 default:
7462 case bfd_reloc_outofrange:
7463 abort ();
7465 case bfd_reloc_overflow:
7466 if (link_order->type == bfd_section_reloc_link_order)
7467 sym_name = bfd_section_name (output_bfd,
7468 link_order->u.reloc.p->u.section);
7469 else
7470 sym_name = link_order->u.reloc.p->u.name;
7471 if (! ((*info->callbacks->reloc_overflow)
7472 (info, NULL, sym_name, howto->name, addend, NULL,
7473 NULL, (bfd_vma) 0)))
7475 free (buf);
7476 return FALSE;
7478 break;
7480 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7481 link_order->offset, size);
7482 free (buf);
7483 if (! ok)
7484 return FALSE;
7487 /* The address of a reloc is relative to the section in a
7488 relocatable file, and is a virtual address in an executable
7489 file. */
7490 offset = link_order->offset;
7491 if (! info->relocatable)
7492 offset += output_section->vma;
7494 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7496 irel[i].r_offset = offset;
7497 irel[i].r_info = 0;
7498 irel[i].r_addend = 0;
7500 if (bed->s->arch_size == 32)
7501 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7502 else
7503 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7505 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7506 erel = rel_hdr->contents;
7507 if (rel_hdr->sh_type == SHT_REL)
7509 erel += (elf_section_data (output_section)->rel_count
7510 * bed->s->sizeof_rel);
7511 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7513 else
7515 irel[0].r_addend = addend;
7516 erel += (elf_section_data (output_section)->rel_count
7517 * bed->s->sizeof_rela);
7518 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7521 ++elf_section_data (output_section)->rel_count;
7523 return TRUE;
7527 /* Get the output vma of the section pointed to by the sh_link field. */
7529 static bfd_vma
7530 elf_get_linked_section_vma (struct bfd_link_order *p)
7532 Elf_Internal_Shdr **elf_shdrp;
7533 asection *s;
7534 int elfsec;
7536 s = p->u.indirect.section;
7537 elf_shdrp = elf_elfsections (s->owner);
7538 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7539 elfsec = elf_shdrp[elfsec]->sh_link;
7540 /* PR 290:
7541 The Intel C compiler generates SHT_IA_64_UNWIND with
7542 SHF_LINK_ORDER. But it doesn't set theh sh_link or
7543 sh_info fields. Hence we could get the situation
7544 where elfsec is 0. */
7545 if (elfsec == 0)
7547 const struct elf_backend_data *bed
7548 = get_elf_backend_data (s->owner);
7549 if (bed->link_order_error_handler)
7550 bed->link_order_error_handler
7551 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
7552 return 0;
7554 else
7556 s = elf_shdrp[elfsec]->bfd_section;
7557 return s->output_section->vma + s->output_offset;
7562 /* Compare two sections based on the locations of the sections they are
7563 linked to. Used by elf_fixup_link_order. */
7565 static int
7566 compare_link_order (const void * a, const void * b)
7568 bfd_vma apos;
7569 bfd_vma bpos;
7571 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7572 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7573 if (apos < bpos)
7574 return -1;
7575 return apos > bpos;
7579 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7580 order as their linked sections. Returns false if this could not be done
7581 because an output section includes both ordered and unordered
7582 sections. Ideally we'd do this in the linker proper. */
7584 static bfd_boolean
7585 elf_fixup_link_order (bfd *abfd, asection *o)
7587 int seen_linkorder;
7588 int seen_other;
7589 int n;
7590 struct bfd_link_order *p;
7591 bfd *sub;
7592 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7593 int elfsec;
7594 struct bfd_link_order **sections;
7595 asection *s;
7596 bfd_vma offset;
7598 seen_other = 0;
7599 seen_linkorder = 0;
7600 for (p = o->link_order_head; p != NULL; p = p->next)
7602 if (p->type == bfd_indirect_link_order
7603 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7604 == bfd_target_elf_flavour)
7605 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7607 s = p->u.indirect.section;
7608 elfsec = _bfd_elf_section_from_bfd_section (sub, s);
7609 if (elfsec != -1
7610 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7611 seen_linkorder++;
7612 else
7613 seen_other++;
7615 else
7616 seen_other++;
7619 if (!seen_linkorder)
7620 return TRUE;
7622 if (seen_other && seen_linkorder)
7624 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
7626 bfd_set_error (bfd_error_bad_value);
7627 return FALSE;
7630 sections = (struct bfd_link_order **)
7631 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7632 seen_linkorder = 0;
7634 for (p = o->link_order_head; p != NULL; p = p->next)
7636 sections[seen_linkorder++] = p;
7638 /* Sort the input sections in the order of their linked section. */
7639 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7640 compare_link_order);
7642 /* Change the offsets of the sections. */
7643 offset = 0;
7644 for (n = 0; n < seen_linkorder; n++)
7646 s = sections[n]->u.indirect.section;
7647 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7648 s->output_offset = offset;
7649 sections[n]->offset = offset;
7650 offset += sections[n]->size;
7653 return TRUE;
7657 /* Do the final step of an ELF link. */
7659 bfd_boolean
7660 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7662 bfd_boolean dynamic;
7663 bfd_boolean emit_relocs;
7664 bfd *dynobj;
7665 struct elf_final_link_info finfo;
7666 register asection *o;
7667 register struct bfd_link_order *p;
7668 register bfd *sub;
7669 bfd_size_type max_contents_size;
7670 bfd_size_type max_external_reloc_size;
7671 bfd_size_type max_internal_reloc_count;
7672 bfd_size_type max_sym_count;
7673 bfd_size_type max_sym_shndx_count;
7674 file_ptr off;
7675 Elf_Internal_Sym elfsym;
7676 unsigned int i;
7677 Elf_Internal_Shdr *symtab_hdr;
7678 Elf_Internal_Shdr *symtab_shndx_hdr;
7679 Elf_Internal_Shdr *symstrtab_hdr;
7680 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7681 struct elf_outext_info eoinfo;
7682 bfd_boolean merged;
7683 size_t relativecount = 0;
7684 asection *reldyn = 0;
7685 bfd_size_type amt;
7687 if (! is_elf_hash_table (info->hash))
7688 return FALSE;
7690 if (info->shared)
7691 abfd->flags |= DYNAMIC;
7693 dynamic = elf_hash_table (info)->dynamic_sections_created;
7694 dynobj = elf_hash_table (info)->dynobj;
7696 emit_relocs = (info->relocatable
7697 || info->emitrelocations
7698 || bed->elf_backend_emit_relocs);
7700 finfo.info = info;
7701 finfo.output_bfd = abfd;
7702 finfo.symstrtab = _bfd_elf_stringtab_init ();
7703 if (finfo.symstrtab == NULL)
7704 return FALSE;
7706 if (! dynamic)
7708 finfo.dynsym_sec = NULL;
7709 finfo.hash_sec = NULL;
7710 finfo.symver_sec = NULL;
7712 else
7714 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7715 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7716 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7717 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7718 /* Note that it is OK if symver_sec is NULL. */
7721 finfo.contents = NULL;
7722 finfo.external_relocs = NULL;
7723 finfo.internal_relocs = NULL;
7724 finfo.external_syms = NULL;
7725 finfo.locsym_shndx = NULL;
7726 finfo.internal_syms = NULL;
7727 finfo.indices = NULL;
7728 finfo.sections = NULL;
7729 finfo.symbuf = NULL;
7730 finfo.symshndxbuf = NULL;
7731 finfo.symbuf_count = 0;
7732 finfo.shndxbuf_size = 0;
7734 /* Count up the number of relocations we will output for each output
7735 section, so that we know the sizes of the reloc sections. We
7736 also figure out some maximum sizes. */
7737 max_contents_size = 0;
7738 max_external_reloc_size = 0;
7739 max_internal_reloc_count = 0;
7740 max_sym_count = 0;
7741 max_sym_shndx_count = 0;
7742 merged = FALSE;
7743 for (o = abfd->sections; o != NULL; o = o->next)
7745 struct bfd_elf_section_data *esdo = elf_section_data (o);
7746 o->reloc_count = 0;
7748 for (p = o->link_order_head; p != NULL; p = p->next)
7750 unsigned int reloc_count = 0;
7751 struct bfd_elf_section_data *esdi = NULL;
7752 unsigned int *rel_count1;
7754 if (p->type == bfd_section_reloc_link_order
7755 || p->type == bfd_symbol_reloc_link_order)
7756 reloc_count = 1;
7757 else if (p->type == bfd_indirect_link_order)
7759 asection *sec;
7761 sec = p->u.indirect.section;
7762 esdi = elf_section_data (sec);
7764 /* Mark all sections which are to be included in the
7765 link. This will normally be every section. We need
7766 to do this so that we can identify any sections which
7767 the linker has decided to not include. */
7768 sec->linker_mark = TRUE;
7770 if (sec->flags & SEC_MERGE)
7771 merged = TRUE;
7773 if (info->relocatable || info->emitrelocations)
7774 reloc_count = sec->reloc_count;
7775 else if (bed->elf_backend_count_relocs)
7777 Elf_Internal_Rela * relocs;
7779 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7780 info->keep_memory);
7782 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7784 if (elf_section_data (o)->relocs != relocs)
7785 free (relocs);
7788 if (sec->rawsize > max_contents_size)
7789 max_contents_size = sec->rawsize;
7790 if (sec->size > max_contents_size)
7791 max_contents_size = sec->size;
7793 /* We are interested in just local symbols, not all
7794 symbols. */
7795 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7796 && (sec->owner->flags & DYNAMIC) == 0)
7798 size_t sym_count;
7800 if (elf_bad_symtab (sec->owner))
7801 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7802 / bed->s->sizeof_sym);
7803 else
7804 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7806 if (sym_count > max_sym_count)
7807 max_sym_count = sym_count;
7809 if (sym_count > max_sym_shndx_count
7810 && elf_symtab_shndx (sec->owner) != 0)
7811 max_sym_shndx_count = sym_count;
7813 if ((sec->flags & SEC_RELOC) != 0)
7815 size_t ext_size;
7817 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7818 if (ext_size > max_external_reloc_size)
7819 max_external_reloc_size = ext_size;
7820 if (sec->reloc_count > max_internal_reloc_count)
7821 max_internal_reloc_count = sec->reloc_count;
7826 if (reloc_count == 0)
7827 continue;
7829 o->reloc_count += reloc_count;
7831 /* MIPS may have a mix of REL and RELA relocs on sections.
7832 To support this curious ABI we keep reloc counts in
7833 elf_section_data too. We must be careful to add the
7834 relocations from the input section to the right output
7835 count. FIXME: Get rid of one count. We have
7836 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7837 rel_count1 = &esdo->rel_count;
7838 if (esdi != NULL)
7840 bfd_boolean same_size;
7841 bfd_size_type entsize1;
7843 entsize1 = esdi->rel_hdr.sh_entsize;
7844 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7845 || entsize1 == bed->s->sizeof_rela);
7846 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7848 if (!same_size)
7849 rel_count1 = &esdo->rel_count2;
7851 if (esdi->rel_hdr2 != NULL)
7853 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7854 unsigned int alt_count;
7855 unsigned int *rel_count2;
7857 BFD_ASSERT (entsize2 != entsize1
7858 && (entsize2 == bed->s->sizeof_rel
7859 || entsize2 == bed->s->sizeof_rela));
7861 rel_count2 = &esdo->rel_count2;
7862 if (!same_size)
7863 rel_count2 = &esdo->rel_count;
7865 /* The following is probably too simplistic if the
7866 backend counts output relocs unusually. */
7867 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7868 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
7869 *rel_count2 += alt_count;
7870 reloc_count -= alt_count;
7873 *rel_count1 += reloc_count;
7876 if (o->reloc_count > 0)
7877 o->flags |= SEC_RELOC;
7878 else
7880 /* Explicitly clear the SEC_RELOC flag. The linker tends to
7881 set it (this is probably a bug) and if it is set
7882 assign_section_numbers will create a reloc section. */
7883 o->flags &=~ SEC_RELOC;
7886 /* If the SEC_ALLOC flag is not set, force the section VMA to
7887 zero. This is done in elf_fake_sections as well, but forcing
7888 the VMA to 0 here will ensure that relocs against these
7889 sections are handled correctly. */
7890 if ((o->flags & SEC_ALLOC) == 0
7891 && ! o->user_set_vma)
7892 o->vma = 0;
7895 if (! info->relocatable && merged)
7896 elf_link_hash_traverse (elf_hash_table (info),
7897 _bfd_elf_link_sec_merge_syms, abfd);
7899 /* Figure out the file positions for everything but the symbol table
7900 and the relocs. We set symcount to force assign_section_numbers
7901 to create a symbol table. */
7902 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
7903 BFD_ASSERT (! abfd->output_has_begun);
7904 if (! _bfd_elf_compute_section_file_positions (abfd, info))
7905 goto error_return;
7907 /* Set sizes, and assign file positions for reloc sections. */
7908 for (o = abfd->sections; o != NULL; o = o->next)
7910 if ((o->flags & SEC_RELOC) != 0)
7912 if (!(_bfd_elf_link_size_reloc_section
7913 (abfd, &elf_section_data (o)->rel_hdr, o)))
7914 goto error_return;
7916 if (elf_section_data (o)->rel_hdr2
7917 && !(_bfd_elf_link_size_reloc_section
7918 (abfd, elf_section_data (o)->rel_hdr2, o)))
7919 goto error_return;
7922 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
7923 to count upwards while actually outputting the relocations. */
7924 elf_section_data (o)->rel_count = 0;
7925 elf_section_data (o)->rel_count2 = 0;
7928 _bfd_elf_assign_file_positions_for_relocs (abfd);
7930 /* We have now assigned file positions for all the sections except
7931 .symtab and .strtab. We start the .symtab section at the current
7932 file position, and write directly to it. We build the .strtab
7933 section in memory. */
7934 bfd_get_symcount (abfd) = 0;
7935 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
7936 /* sh_name is set in prep_headers. */
7937 symtab_hdr->sh_type = SHT_SYMTAB;
7938 /* sh_flags, sh_addr and sh_size all start off zero. */
7939 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
7940 /* sh_link is set in assign_section_numbers. */
7941 /* sh_info is set below. */
7942 /* sh_offset is set just below. */
7943 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
7945 off = elf_tdata (abfd)->next_file_pos;
7946 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
7948 /* Note that at this point elf_tdata (abfd)->next_file_pos is
7949 incorrect. We do not yet know the size of the .symtab section.
7950 We correct next_file_pos below, after we do know the size. */
7952 /* Allocate a buffer to hold swapped out symbols. This is to avoid
7953 continuously seeking to the right position in the file. */
7954 if (! info->keep_memory || max_sym_count < 20)
7955 finfo.symbuf_size = 20;
7956 else
7957 finfo.symbuf_size = max_sym_count;
7958 amt = finfo.symbuf_size;
7959 amt *= bed->s->sizeof_sym;
7960 finfo.symbuf = bfd_malloc (amt);
7961 if (finfo.symbuf == NULL)
7962 goto error_return;
7963 if (elf_numsections (abfd) > SHN_LORESERVE)
7965 /* Wild guess at number of output symbols. realloc'd as needed. */
7966 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
7967 finfo.shndxbuf_size = amt;
7968 amt *= sizeof (Elf_External_Sym_Shndx);
7969 finfo.symshndxbuf = bfd_zmalloc (amt);
7970 if (finfo.symshndxbuf == NULL)
7971 goto error_return;
7974 /* Start writing out the symbol table. The first symbol is always a
7975 dummy symbol. */
7976 if (info->strip != strip_all
7977 || emit_relocs)
7979 elfsym.st_value = 0;
7980 elfsym.st_size = 0;
7981 elfsym.st_info = 0;
7982 elfsym.st_other = 0;
7983 elfsym.st_shndx = SHN_UNDEF;
7984 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
7985 NULL))
7986 goto error_return;
7989 /* Output a symbol for each section. We output these even if we are
7990 discarding local symbols, since they are used for relocs. These
7991 symbols have no names. We store the index of each one in the
7992 index field of the section, so that we can find it again when
7993 outputting relocs. */
7994 if (info->strip != strip_all
7995 || emit_relocs)
7997 elfsym.st_size = 0;
7998 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
7999 elfsym.st_other = 0;
8000 for (i = 1; i < elf_numsections (abfd); i++)
8002 o = bfd_section_from_elf_index (abfd, i);
8003 if (o != NULL)
8004 o->target_index = bfd_get_symcount (abfd);
8005 elfsym.st_shndx = i;
8006 if (info->relocatable || o == NULL)
8007 elfsym.st_value = 0;
8008 else
8009 elfsym.st_value = o->vma;
8010 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
8011 goto error_return;
8012 if (i == SHN_LORESERVE - 1)
8013 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
8017 /* Allocate some memory to hold information read in from the input
8018 files. */
8019 if (max_contents_size != 0)
8021 finfo.contents = bfd_malloc (max_contents_size);
8022 if (finfo.contents == NULL)
8023 goto error_return;
8026 if (max_external_reloc_size != 0)
8028 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
8029 if (finfo.external_relocs == NULL)
8030 goto error_return;
8033 if (max_internal_reloc_count != 0)
8035 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
8036 amt *= sizeof (Elf_Internal_Rela);
8037 finfo.internal_relocs = bfd_malloc (amt);
8038 if (finfo.internal_relocs == NULL)
8039 goto error_return;
8042 if (max_sym_count != 0)
8044 amt = max_sym_count * bed->s->sizeof_sym;
8045 finfo.external_syms = bfd_malloc (amt);
8046 if (finfo.external_syms == NULL)
8047 goto error_return;
8049 amt = max_sym_count * sizeof (Elf_Internal_Sym);
8050 finfo.internal_syms = bfd_malloc (amt);
8051 if (finfo.internal_syms == NULL)
8052 goto error_return;
8054 amt = max_sym_count * sizeof (long);
8055 finfo.indices = bfd_malloc (amt);
8056 if (finfo.indices == NULL)
8057 goto error_return;
8059 amt = max_sym_count * sizeof (asection *);
8060 finfo.sections = bfd_malloc (amt);
8061 if (finfo.sections == NULL)
8062 goto error_return;
8065 if (max_sym_shndx_count != 0)
8067 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8068 finfo.locsym_shndx = bfd_malloc (amt);
8069 if (finfo.locsym_shndx == NULL)
8070 goto error_return;
8073 if (elf_hash_table (info)->tls_sec)
8075 bfd_vma base, end = 0;
8076 asection *sec;
8078 for (sec = elf_hash_table (info)->tls_sec;
8079 sec && (sec->flags & SEC_THREAD_LOCAL);
8080 sec = sec->next)
8082 bfd_vma size = sec->size;
8084 if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8086 struct bfd_link_order *o;
8088 for (o = sec->link_order_head; o != NULL; o = o->next)
8089 if (size < o->offset + o->size)
8090 size = o->offset + o->size;
8092 end = sec->vma + size;
8094 base = elf_hash_table (info)->tls_sec->vma;
8095 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8096 elf_hash_table (info)->tls_size = end - base;
8099 /* Reorder SHF_LINK_ORDER sections. */
8100 for (o = abfd->sections; o != NULL; o = o->next)
8102 if (!elf_fixup_link_order (abfd, o))
8103 return FALSE;
8106 /* Since ELF permits relocations to be against local symbols, we
8107 must have the local symbols available when we do the relocations.
8108 Since we would rather only read the local symbols once, and we
8109 would rather not keep them in memory, we handle all the
8110 relocations for a single input file at the same time.
8112 Unfortunately, there is no way to know the total number of local
8113 symbols until we have seen all of them, and the local symbol
8114 indices precede the global symbol indices. This means that when
8115 we are generating relocatable output, and we see a reloc against
8116 a global symbol, we can not know the symbol index until we have
8117 finished examining all the local symbols to see which ones we are
8118 going to output. To deal with this, we keep the relocations in
8119 memory, and don't output them until the end of the link. This is
8120 an unfortunate waste of memory, but I don't see a good way around
8121 it. Fortunately, it only happens when performing a relocatable
8122 link, which is not the common case. FIXME: If keep_memory is set
8123 we could write the relocs out and then read them again; I don't
8124 know how bad the memory loss will be. */
8126 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8127 sub->output_has_begun = FALSE;
8128 for (o = abfd->sections; o != NULL; o = o->next)
8130 for (p = o->link_order_head; p != NULL; p = p->next)
8132 if (p->type == bfd_indirect_link_order
8133 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8134 == bfd_target_elf_flavour)
8135 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8137 if (! sub->output_has_begun)
8139 if (! elf_link_input_bfd (&finfo, sub))
8140 goto error_return;
8141 sub->output_has_begun = TRUE;
8144 else if (p->type == bfd_section_reloc_link_order
8145 || p->type == bfd_symbol_reloc_link_order)
8147 if (! elf_reloc_link_order (abfd, info, o, p))
8148 goto error_return;
8150 else
8152 if (! _bfd_default_link_order (abfd, info, o, p))
8153 goto error_return;
8158 /* Output any global symbols that got converted to local in a
8159 version script or due to symbol visibility. We do this in a
8160 separate step since ELF requires all local symbols to appear
8161 prior to any global symbols. FIXME: We should only do this if
8162 some global symbols were, in fact, converted to become local.
8163 FIXME: Will this work correctly with the Irix 5 linker? */
8164 eoinfo.failed = FALSE;
8165 eoinfo.finfo = &finfo;
8166 eoinfo.localsyms = TRUE;
8167 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8168 &eoinfo);
8169 if (eoinfo.failed)
8170 return FALSE;
8172 /* That wrote out all the local symbols. Finish up the symbol table
8173 with the global symbols. Even if we want to strip everything we
8174 can, we still need to deal with those global symbols that got
8175 converted to local in a version script. */
8177 /* The sh_info field records the index of the first non local symbol. */
8178 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8180 if (dynamic
8181 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8183 Elf_Internal_Sym sym;
8184 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8185 long last_local = 0;
8187 /* Write out the section symbols for the output sections. */
8188 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
8190 asection *s;
8192 sym.st_size = 0;
8193 sym.st_name = 0;
8194 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8195 sym.st_other = 0;
8197 for (s = abfd->sections; s != NULL; s = s->next)
8199 int indx;
8200 bfd_byte *dest;
8201 long dynindx;
8203 dynindx = elf_section_data (s)->dynindx;
8204 if (dynindx <= 0)
8205 continue;
8206 indx = elf_section_data (s)->this_idx;
8207 BFD_ASSERT (indx > 0);
8208 sym.st_shndx = indx;
8209 sym.st_value = s->vma;
8210 dest = dynsym + dynindx * bed->s->sizeof_sym;
8211 if (last_local < dynindx)
8212 last_local = dynindx;
8213 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8217 /* Write out the local dynsyms. */
8218 if (elf_hash_table (info)->dynlocal)
8220 struct elf_link_local_dynamic_entry *e;
8221 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8223 asection *s;
8224 bfd_byte *dest;
8226 sym.st_size = e->isym.st_size;
8227 sym.st_other = e->isym.st_other;
8229 /* Copy the internal symbol as is.
8230 Note that we saved a word of storage and overwrote
8231 the original st_name with the dynstr_index. */
8232 sym = e->isym;
8234 if (e->isym.st_shndx != SHN_UNDEF
8235 && (e->isym.st_shndx < SHN_LORESERVE
8236 || e->isym.st_shndx > SHN_HIRESERVE))
8238 s = bfd_section_from_elf_index (e->input_bfd,
8239 e->isym.st_shndx);
8241 sym.st_shndx =
8242 elf_section_data (s->output_section)->this_idx;
8243 sym.st_value = (s->output_section->vma
8244 + s->output_offset
8245 + e->isym.st_value);
8248 if (last_local < e->dynindx)
8249 last_local = e->dynindx;
8251 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8252 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8256 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8257 last_local + 1;
8260 /* We get the global symbols from the hash table. */
8261 eoinfo.failed = FALSE;
8262 eoinfo.localsyms = FALSE;
8263 eoinfo.finfo = &finfo;
8264 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8265 &eoinfo);
8266 if (eoinfo.failed)
8267 return FALSE;
8269 /* If backend needs to output some symbols not present in the hash
8270 table, do it now. */
8271 if (bed->elf_backend_output_arch_syms)
8273 typedef bfd_boolean (*out_sym_func)
8274 (void *, const char *, Elf_Internal_Sym *, asection *,
8275 struct elf_link_hash_entry *);
8277 if (! ((*bed->elf_backend_output_arch_syms)
8278 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8279 return FALSE;
8282 /* Flush all symbols to the file. */
8283 if (! elf_link_flush_output_syms (&finfo, bed))
8284 return FALSE;
8286 /* Now we know the size of the symtab section. */
8287 off += symtab_hdr->sh_size;
8289 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8290 if (symtab_shndx_hdr->sh_name != 0)
8292 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8293 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8294 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8295 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8296 symtab_shndx_hdr->sh_size = amt;
8298 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8299 off, TRUE);
8301 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8302 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8303 return FALSE;
8307 /* Finish up and write out the symbol string table (.strtab)
8308 section. */
8309 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8310 /* sh_name was set in prep_headers. */
8311 symstrtab_hdr->sh_type = SHT_STRTAB;
8312 symstrtab_hdr->sh_flags = 0;
8313 symstrtab_hdr->sh_addr = 0;
8314 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8315 symstrtab_hdr->sh_entsize = 0;
8316 symstrtab_hdr->sh_link = 0;
8317 symstrtab_hdr->sh_info = 0;
8318 /* sh_offset is set just below. */
8319 symstrtab_hdr->sh_addralign = 1;
8321 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8322 elf_tdata (abfd)->next_file_pos = off;
8324 if (bfd_get_symcount (abfd) > 0)
8326 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8327 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8328 return FALSE;
8331 /* Adjust the relocs to have the correct symbol indices. */
8332 for (o = abfd->sections; o != NULL; o = o->next)
8334 if ((o->flags & SEC_RELOC) == 0)
8335 continue;
8337 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8338 elf_section_data (o)->rel_count,
8339 elf_section_data (o)->rel_hashes);
8340 if (elf_section_data (o)->rel_hdr2 != NULL)
8341 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8342 elf_section_data (o)->rel_count2,
8343 (elf_section_data (o)->rel_hashes
8344 + elf_section_data (o)->rel_count));
8346 /* Set the reloc_count field to 0 to prevent write_relocs from
8347 trying to swap the relocs out itself. */
8348 o->reloc_count = 0;
8351 if (dynamic && info->combreloc && dynobj != NULL)
8352 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8354 /* If we are linking against a dynamic object, or generating a
8355 shared library, finish up the dynamic linking information. */
8356 if (dynamic)
8358 bfd_byte *dyncon, *dynconend;
8360 /* Fix up .dynamic entries. */
8361 o = bfd_get_section_by_name (dynobj, ".dynamic");
8362 BFD_ASSERT (o != NULL);
8364 dyncon = o->contents;
8365 dynconend = o->contents + o->size;
8366 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8368 Elf_Internal_Dyn dyn;
8369 const char *name;
8370 unsigned int type;
8372 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8374 switch (dyn.d_tag)
8376 default:
8377 continue;
8378 case DT_NULL:
8379 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8381 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8383 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8384 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8385 default: continue;
8387 dyn.d_un.d_val = relativecount;
8388 relativecount = 0;
8389 break;
8391 continue;
8393 case DT_INIT:
8394 name = info->init_function;
8395 goto get_sym;
8396 case DT_FINI:
8397 name = info->fini_function;
8398 get_sym:
8400 struct elf_link_hash_entry *h;
8402 h = elf_link_hash_lookup (elf_hash_table (info), name,
8403 FALSE, FALSE, TRUE);
8404 if (h != NULL
8405 && (h->root.type == bfd_link_hash_defined
8406 || h->root.type == bfd_link_hash_defweak))
8408 dyn.d_un.d_val = h->root.u.def.value;
8409 o = h->root.u.def.section;
8410 if (o->output_section != NULL)
8411 dyn.d_un.d_val += (o->output_section->vma
8412 + o->output_offset);
8413 else
8415 /* The symbol is imported from another shared
8416 library and does not apply to this one. */
8417 dyn.d_un.d_val = 0;
8419 break;
8422 continue;
8424 case DT_PREINIT_ARRAYSZ:
8425 name = ".preinit_array";
8426 goto get_size;
8427 case DT_INIT_ARRAYSZ:
8428 name = ".init_array";
8429 goto get_size;
8430 case DT_FINI_ARRAYSZ:
8431 name = ".fini_array";
8432 get_size:
8433 o = bfd_get_section_by_name (abfd, name);
8434 if (o == NULL)
8436 (*_bfd_error_handler)
8437 (_("%B: could not find output section %s"), abfd, name);
8438 goto error_return;
8440 if (o->size == 0)
8441 (*_bfd_error_handler)
8442 (_("warning: %s section has zero size"), name);
8443 dyn.d_un.d_val = o->size;
8444 break;
8446 case DT_PREINIT_ARRAY:
8447 name = ".preinit_array";
8448 goto get_vma;
8449 case DT_INIT_ARRAY:
8450 name = ".init_array";
8451 goto get_vma;
8452 case DT_FINI_ARRAY:
8453 name = ".fini_array";
8454 goto get_vma;
8456 case DT_HASH:
8457 name = ".hash";
8458 goto get_vma;
8459 case DT_STRTAB:
8460 name = ".dynstr";
8461 goto get_vma;
8462 case DT_SYMTAB:
8463 name = ".dynsym";
8464 goto get_vma;
8465 case DT_VERDEF:
8466 name = ".gnu.version_d";
8467 goto get_vma;
8468 case DT_VERNEED:
8469 name = ".gnu.version_r";
8470 goto get_vma;
8471 case DT_VERSYM:
8472 name = ".gnu.version";
8473 get_vma:
8474 o = bfd_get_section_by_name (abfd, name);
8475 if (o == NULL)
8477 (*_bfd_error_handler)
8478 (_("%B: could not find output section %s"), abfd, name);
8479 goto error_return;
8481 dyn.d_un.d_ptr = o->vma;
8482 break;
8484 case DT_REL:
8485 case DT_RELA:
8486 case DT_RELSZ:
8487 case DT_RELASZ:
8488 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8489 type = SHT_REL;
8490 else
8491 type = SHT_RELA;
8492 dyn.d_un.d_val = 0;
8493 for (i = 1; i < elf_numsections (abfd); i++)
8495 Elf_Internal_Shdr *hdr;
8497 hdr = elf_elfsections (abfd)[i];
8498 if (hdr->sh_type == type
8499 && (hdr->sh_flags & SHF_ALLOC) != 0)
8501 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8502 dyn.d_un.d_val += hdr->sh_size;
8503 else
8505 if (dyn.d_un.d_val == 0
8506 || hdr->sh_addr < dyn.d_un.d_val)
8507 dyn.d_un.d_val = hdr->sh_addr;
8511 break;
8513 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8517 /* If we have created any dynamic sections, then output them. */
8518 if (dynobj != NULL)
8520 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8521 goto error_return;
8523 for (o = dynobj->sections; o != NULL; o = o->next)
8525 if ((o->flags & SEC_HAS_CONTENTS) == 0
8526 || o->size == 0
8527 || o->output_section == bfd_abs_section_ptr)
8528 continue;
8529 if ((o->flags & SEC_LINKER_CREATED) == 0)
8531 /* At this point, we are only interested in sections
8532 created by _bfd_elf_link_create_dynamic_sections. */
8533 continue;
8535 if (elf_hash_table (info)->stab_info.stabstr == o)
8536 continue;
8537 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8538 continue;
8539 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8540 != SHT_STRTAB)
8541 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8543 if (! bfd_set_section_contents (abfd, o->output_section,
8544 o->contents,
8545 (file_ptr) o->output_offset,
8546 o->size))
8547 goto error_return;
8549 else
8551 /* The contents of the .dynstr section are actually in a
8552 stringtab. */
8553 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8554 if (bfd_seek (abfd, off, SEEK_SET) != 0
8555 || ! _bfd_elf_strtab_emit (abfd,
8556 elf_hash_table (info)->dynstr))
8557 goto error_return;
8562 if (info->relocatable)
8564 bfd_boolean failed = FALSE;
8566 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8567 if (failed)
8568 goto error_return;
8571 /* If we have optimized stabs strings, output them. */
8572 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8574 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8575 goto error_return;
8578 if (info->eh_frame_hdr)
8580 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8581 goto error_return;
8584 if (finfo.symstrtab != NULL)
8585 _bfd_stringtab_free (finfo.symstrtab);
8586 if (finfo.contents != NULL)
8587 free (finfo.contents);
8588 if (finfo.external_relocs != NULL)
8589 free (finfo.external_relocs);
8590 if (finfo.internal_relocs != NULL)
8591 free (finfo.internal_relocs);
8592 if (finfo.external_syms != NULL)
8593 free (finfo.external_syms);
8594 if (finfo.locsym_shndx != NULL)
8595 free (finfo.locsym_shndx);
8596 if (finfo.internal_syms != NULL)
8597 free (finfo.internal_syms);
8598 if (finfo.indices != NULL)
8599 free (finfo.indices);
8600 if (finfo.sections != NULL)
8601 free (finfo.sections);
8602 if (finfo.symbuf != NULL)
8603 free (finfo.symbuf);
8604 if (finfo.symshndxbuf != NULL)
8605 free (finfo.symshndxbuf);
8606 for (o = abfd->sections; o != NULL; o = o->next)
8608 if ((o->flags & SEC_RELOC) != 0
8609 && elf_section_data (o)->rel_hashes != NULL)
8610 free (elf_section_data (o)->rel_hashes);
8613 elf_tdata (abfd)->linker = TRUE;
8615 return TRUE;
8617 error_return:
8618 if (finfo.symstrtab != NULL)
8619 _bfd_stringtab_free (finfo.symstrtab);
8620 if (finfo.contents != NULL)
8621 free (finfo.contents);
8622 if (finfo.external_relocs != NULL)
8623 free (finfo.external_relocs);
8624 if (finfo.internal_relocs != NULL)
8625 free (finfo.internal_relocs);
8626 if (finfo.external_syms != NULL)
8627 free (finfo.external_syms);
8628 if (finfo.locsym_shndx != NULL)
8629 free (finfo.locsym_shndx);
8630 if (finfo.internal_syms != NULL)
8631 free (finfo.internal_syms);
8632 if (finfo.indices != NULL)
8633 free (finfo.indices);
8634 if (finfo.sections != NULL)
8635 free (finfo.sections);
8636 if (finfo.symbuf != NULL)
8637 free (finfo.symbuf);
8638 if (finfo.symshndxbuf != NULL)
8639 free (finfo.symshndxbuf);
8640 for (o = abfd->sections; o != NULL; o = o->next)
8642 if ((o->flags & SEC_RELOC) != 0
8643 && elf_section_data (o)->rel_hashes != NULL)
8644 free (elf_section_data (o)->rel_hashes);
8647 return FALSE;
8650 /* Garbage collect unused sections. */
8652 /* The mark phase of garbage collection. For a given section, mark
8653 it and any sections in this section's group, and all the sections
8654 which define symbols to which it refers. */
8656 typedef asection * (*gc_mark_hook_fn)
8657 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8658 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8660 bfd_boolean
8661 _bfd_elf_gc_mark (struct bfd_link_info *info,
8662 asection *sec,
8663 gc_mark_hook_fn gc_mark_hook)
8665 bfd_boolean ret;
8666 asection *group_sec;
8668 sec->gc_mark = 1;
8670 /* Mark all the sections in the group. */
8671 group_sec = elf_section_data (sec)->next_in_group;
8672 if (group_sec && !group_sec->gc_mark)
8673 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
8674 return FALSE;
8676 /* Look through the section relocs. */
8677 ret = TRUE;
8678 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8680 Elf_Internal_Rela *relstart, *rel, *relend;
8681 Elf_Internal_Shdr *symtab_hdr;
8682 struct elf_link_hash_entry **sym_hashes;
8683 size_t nlocsyms;
8684 size_t extsymoff;
8685 bfd *input_bfd = sec->owner;
8686 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8687 Elf_Internal_Sym *isym = NULL;
8688 int r_sym_shift;
8690 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8691 sym_hashes = elf_sym_hashes (input_bfd);
8693 /* Read the local symbols. */
8694 if (elf_bad_symtab (input_bfd))
8696 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8697 extsymoff = 0;
8699 else
8700 extsymoff = nlocsyms = symtab_hdr->sh_info;
8702 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8703 if (isym == NULL && nlocsyms != 0)
8705 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8706 NULL, NULL, NULL);
8707 if (isym == NULL)
8708 return FALSE;
8711 /* Read the relocations. */
8712 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8713 info->keep_memory);
8714 if (relstart == NULL)
8716 ret = FALSE;
8717 goto out1;
8719 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8721 if (bed->s->arch_size == 32)
8722 r_sym_shift = 8;
8723 else
8724 r_sym_shift = 32;
8726 for (rel = relstart; rel < relend; rel++)
8728 unsigned long r_symndx;
8729 asection *rsec;
8730 struct elf_link_hash_entry *h;
8732 r_symndx = rel->r_info >> r_sym_shift;
8733 if (r_symndx == 0)
8734 continue;
8736 if (r_symndx >= nlocsyms
8737 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8739 h = sym_hashes[r_symndx - extsymoff];
8740 while (h->root.type == bfd_link_hash_indirect
8741 || h->root.type == bfd_link_hash_warning)
8742 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8743 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8745 else
8747 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8750 if (rsec && !rsec->gc_mark)
8752 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8753 rsec->gc_mark = 1;
8754 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
8756 ret = FALSE;
8757 goto out2;
8762 out2:
8763 if (elf_section_data (sec)->relocs != relstart)
8764 free (relstart);
8765 out1:
8766 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8768 if (! info->keep_memory)
8769 free (isym);
8770 else
8771 symtab_hdr->contents = (unsigned char *) isym;
8775 return ret;
8778 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8780 static bfd_boolean
8781 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
8783 int *idx = idxptr;
8785 if (h->root.type == bfd_link_hash_warning)
8786 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8788 if (h->dynindx != -1
8789 && ((h->root.type != bfd_link_hash_defined
8790 && h->root.type != bfd_link_hash_defweak)
8791 || h->root.u.def.section->gc_mark))
8792 h->dynindx = (*idx)++;
8794 return TRUE;
8797 /* The sweep phase of garbage collection. Remove all garbage sections. */
8799 typedef bfd_boolean (*gc_sweep_hook_fn)
8800 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8802 static bfd_boolean
8803 elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
8805 bfd *sub;
8807 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8809 asection *o;
8811 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8812 continue;
8814 for (o = sub->sections; o != NULL; o = o->next)
8816 /* Keep debug and special sections. */
8817 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
8818 || (o->flags & (SEC_ALLOC | SEC_LOAD)) == 0)
8819 o->gc_mark = 1;
8821 if (o->gc_mark)
8822 continue;
8824 /* Skip sweeping sections already excluded. */
8825 if (o->flags & SEC_EXCLUDE)
8826 continue;
8828 /* Since this is early in the link process, it is simple
8829 to remove a section from the output. */
8830 o->flags |= SEC_EXCLUDE;
8832 /* But we also have to update some of the relocation
8833 info we collected before. */
8834 if (gc_sweep_hook
8835 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
8837 Elf_Internal_Rela *internal_relocs;
8838 bfd_boolean r;
8840 internal_relocs
8841 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8842 info->keep_memory);
8843 if (internal_relocs == NULL)
8844 return FALSE;
8846 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8848 if (elf_section_data (o)->relocs != internal_relocs)
8849 free (internal_relocs);
8851 if (!r)
8852 return FALSE;
8857 /* Remove the symbols that were in the swept sections from the dynamic
8858 symbol table. GCFIXME: Anyone know how to get them out of the
8859 static symbol table as well? */
8861 int i = 0;
8863 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
8865 elf_hash_table (info)->dynsymcount = i;
8868 return TRUE;
8871 /* Propagate collected vtable information. This is called through
8872 elf_link_hash_traverse. */
8874 static bfd_boolean
8875 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
8877 if (h->root.type == bfd_link_hash_warning)
8878 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8880 /* Those that are not vtables. */
8881 if (h->vtable == NULL || h->vtable->parent == NULL)
8882 return TRUE;
8884 /* Those vtables that do not have parents, we cannot merge. */
8885 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
8886 return TRUE;
8888 /* If we've already been done, exit. */
8889 if (h->vtable->used && h->vtable->used[-1])
8890 return TRUE;
8892 /* Make sure the parent's table is up to date. */
8893 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
8895 if (h->vtable->used == NULL)
8897 /* None of this table's entries were referenced. Re-use the
8898 parent's table. */
8899 h->vtable->used = h->vtable->parent->vtable->used;
8900 h->vtable->size = h->vtable->parent->vtable->size;
8902 else
8904 size_t n;
8905 bfd_boolean *cu, *pu;
8907 /* Or the parent's entries into ours. */
8908 cu = h->vtable->used;
8909 cu[-1] = TRUE;
8910 pu = h->vtable->parent->vtable->used;
8911 if (pu != NULL)
8913 const struct elf_backend_data *bed;
8914 unsigned int log_file_align;
8916 bed = get_elf_backend_data (h->root.u.def.section->owner);
8917 log_file_align = bed->s->log_file_align;
8918 n = h->vtable->parent->vtable->size >> log_file_align;
8919 while (n--)
8921 if (*pu)
8922 *cu = TRUE;
8923 pu++;
8924 cu++;
8929 return TRUE;
8932 static bfd_boolean
8933 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
8935 asection *sec;
8936 bfd_vma hstart, hend;
8937 Elf_Internal_Rela *relstart, *relend, *rel;
8938 const struct elf_backend_data *bed;
8939 unsigned int log_file_align;
8941 if (h->root.type == bfd_link_hash_warning)
8942 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8944 /* Take care of both those symbols that do not describe vtables as
8945 well as those that are not loaded. */
8946 if (h->vtable == NULL || h->vtable->parent == NULL)
8947 return TRUE;
8949 BFD_ASSERT (h->root.type == bfd_link_hash_defined
8950 || h->root.type == bfd_link_hash_defweak);
8952 sec = h->root.u.def.section;
8953 hstart = h->root.u.def.value;
8954 hend = hstart + h->size;
8956 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
8957 if (!relstart)
8958 return *(bfd_boolean *) okp = FALSE;
8959 bed = get_elf_backend_data (sec->owner);
8960 log_file_align = bed->s->log_file_align;
8962 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8964 for (rel = relstart; rel < relend; ++rel)
8965 if (rel->r_offset >= hstart && rel->r_offset < hend)
8967 /* If the entry is in use, do nothing. */
8968 if (h->vtable->used
8969 && (rel->r_offset - hstart) < h->vtable->size)
8971 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
8972 if (h->vtable->used[entry])
8973 continue;
8975 /* Otherwise, kill it. */
8976 rel->r_offset = rel->r_info = rel->r_addend = 0;
8979 return TRUE;
8982 /* Mark sections containing dynamically referenced symbols. This is called
8983 through elf_link_hash_traverse. */
8985 static bfd_boolean
8986 elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h,
8987 void *okp ATTRIBUTE_UNUSED)
8989 if (h->root.type == bfd_link_hash_warning)
8990 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8992 if ((h->root.type == bfd_link_hash_defined
8993 || h->root.type == bfd_link_hash_defweak)
8994 && h->ref_dynamic)
8995 h->root.u.def.section->flags |= SEC_KEEP;
8997 return TRUE;
9000 /* Do mark and sweep of unused sections. */
9002 bfd_boolean
9003 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
9005 bfd_boolean ok = TRUE;
9006 bfd *sub;
9007 asection * (*gc_mark_hook)
9008 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9009 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
9011 if (!get_elf_backend_data (abfd)->can_gc_sections
9012 || info->relocatable
9013 || info->emitrelocations
9014 || info->shared
9015 || !is_elf_hash_table (info->hash))
9017 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
9018 return TRUE;
9021 /* Apply transitive closure to the vtable entry usage info. */
9022 elf_link_hash_traverse (elf_hash_table (info),
9023 elf_gc_propagate_vtable_entries_used,
9024 &ok);
9025 if (!ok)
9026 return FALSE;
9028 /* Kill the vtable relocations that were not used. */
9029 elf_link_hash_traverse (elf_hash_table (info),
9030 elf_gc_smash_unused_vtentry_relocs,
9031 &ok);
9032 if (!ok)
9033 return FALSE;
9035 /* Mark dynamically referenced symbols. */
9036 if (elf_hash_table (info)->dynamic_sections_created)
9037 elf_link_hash_traverse (elf_hash_table (info),
9038 elf_gc_mark_dynamic_ref_symbol,
9039 &ok);
9040 if (!ok)
9041 return FALSE;
9043 /* Grovel through relocs to find out who stays ... */
9044 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
9045 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9047 asection *o;
9049 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9050 continue;
9052 for (o = sub->sections; o != NULL; o = o->next)
9054 if (o->flags & SEC_KEEP)
9056 /* _bfd_elf_discard_section_eh_frame knows how to discard
9057 orphaned FDEs so don't mark sections referenced by the
9058 EH frame section. */
9059 if (strcmp (o->name, ".eh_frame") == 0)
9060 o->gc_mark = 1;
9061 else if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9062 return FALSE;
9067 /* ... and mark SEC_EXCLUDE for those that go. */
9068 if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
9069 return FALSE;
9071 return TRUE;
9074 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9076 bfd_boolean
9077 bfd_elf_gc_record_vtinherit (bfd *abfd,
9078 asection *sec,
9079 struct elf_link_hash_entry *h,
9080 bfd_vma offset)
9082 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9083 struct elf_link_hash_entry **search, *child;
9084 bfd_size_type extsymcount;
9085 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9087 /* The sh_info field of the symtab header tells us where the
9088 external symbols start. We don't care about the local symbols at
9089 this point. */
9090 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9091 if (!elf_bad_symtab (abfd))
9092 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9094 sym_hashes = elf_sym_hashes (abfd);
9095 sym_hashes_end = sym_hashes + extsymcount;
9097 /* Hunt down the child symbol, which is in this section at the same
9098 offset as the relocation. */
9099 for (search = sym_hashes; search != sym_hashes_end; ++search)
9101 if ((child = *search) != NULL
9102 && (child->root.type == bfd_link_hash_defined
9103 || child->root.type == bfd_link_hash_defweak)
9104 && child->root.u.def.section == sec
9105 && child->root.u.def.value == offset)
9106 goto win;
9109 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9110 abfd, sec, (unsigned long) offset);
9111 bfd_set_error (bfd_error_invalid_operation);
9112 return FALSE;
9114 win:
9115 if (!child->vtable)
9117 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9118 if (!child->vtable)
9119 return FALSE;
9121 if (!h)
9123 /* This *should* only be the absolute section. It could potentially
9124 be that someone has defined a non-global vtable though, which
9125 would be bad. It isn't worth paging in the local symbols to be
9126 sure though; that case should simply be handled by the assembler. */
9128 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9130 else
9131 child->vtable->parent = h;
9133 return TRUE;
9136 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9138 bfd_boolean
9139 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9140 asection *sec ATTRIBUTE_UNUSED,
9141 struct elf_link_hash_entry *h,
9142 bfd_vma addend)
9144 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9145 unsigned int log_file_align = bed->s->log_file_align;
9147 if (!h->vtable)
9149 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9150 if (!h->vtable)
9151 return FALSE;
9154 if (addend >= h->vtable->size)
9156 size_t size, bytes, file_align;
9157 bfd_boolean *ptr = h->vtable->used;
9159 /* While the symbol is undefined, we have to be prepared to handle
9160 a zero size. */
9161 file_align = 1 << log_file_align;
9162 if (h->root.type == bfd_link_hash_undefined)
9163 size = addend + file_align;
9164 else
9166 size = h->size;
9167 if (addend >= size)
9169 /* Oops! We've got a reference past the defined end of
9170 the table. This is probably a bug -- shall we warn? */
9171 size = addend + file_align;
9174 size = (size + file_align - 1) & -file_align;
9176 /* Allocate one extra entry for use as a "done" flag for the
9177 consolidation pass. */
9178 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9180 if (ptr)
9182 ptr = bfd_realloc (ptr - 1, bytes);
9184 if (ptr != NULL)
9186 size_t oldbytes;
9188 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9189 * sizeof (bfd_boolean));
9190 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9193 else
9194 ptr = bfd_zmalloc (bytes);
9196 if (ptr == NULL)
9197 return FALSE;
9199 /* And arrange for that done flag to be at index -1. */
9200 h->vtable->used = ptr + 1;
9201 h->vtable->size = size;
9204 h->vtable->used[addend >> log_file_align] = TRUE;
9206 return TRUE;
9209 struct alloc_got_off_arg {
9210 bfd_vma gotoff;
9211 unsigned int got_elt_size;
9214 /* We need a special top-level link routine to convert got reference counts
9215 to real got offsets. */
9217 static bfd_boolean
9218 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
9220 struct alloc_got_off_arg *gofarg = arg;
9222 if (h->root.type == bfd_link_hash_warning)
9223 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9225 if (h->got.refcount > 0)
9227 h->got.offset = gofarg->gotoff;
9228 gofarg->gotoff += gofarg->got_elt_size;
9230 else
9231 h->got.offset = (bfd_vma) -1;
9233 return TRUE;
9236 /* And an accompanying bit to work out final got entry offsets once
9237 we're done. Should be called from final_link. */
9239 bfd_boolean
9240 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
9241 struct bfd_link_info *info)
9243 bfd *i;
9244 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9245 bfd_vma gotoff;
9246 unsigned int got_elt_size = bed->s->arch_size / 8;
9247 struct alloc_got_off_arg gofarg;
9249 if (! is_elf_hash_table (info->hash))
9250 return FALSE;
9252 /* The GOT offset is relative to the .got section, but the GOT header is
9253 put into the .got.plt section, if the backend uses it. */
9254 if (bed->want_got_plt)
9255 gotoff = 0;
9256 else
9257 gotoff = bed->got_header_size;
9259 /* Do the local .got entries first. */
9260 for (i = info->input_bfds; i; i = i->link_next)
9262 bfd_signed_vma *local_got;
9263 bfd_size_type j, locsymcount;
9264 Elf_Internal_Shdr *symtab_hdr;
9266 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
9267 continue;
9269 local_got = elf_local_got_refcounts (i);
9270 if (!local_got)
9271 continue;
9273 symtab_hdr = &elf_tdata (i)->symtab_hdr;
9274 if (elf_bad_symtab (i))
9275 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9276 else
9277 locsymcount = symtab_hdr->sh_info;
9279 for (j = 0; j < locsymcount; ++j)
9281 if (local_got[j] > 0)
9283 local_got[j] = gotoff;
9284 gotoff += got_elt_size;
9286 else
9287 local_got[j] = (bfd_vma) -1;
9291 /* Then the global .got entries. .plt refcounts are handled by
9292 adjust_dynamic_symbol */
9293 gofarg.gotoff = gotoff;
9294 gofarg.got_elt_size = got_elt_size;
9295 elf_link_hash_traverse (elf_hash_table (info),
9296 elf_gc_allocate_got_offsets,
9297 &gofarg);
9298 return TRUE;
9301 /* Many folk need no more in the way of final link than this, once
9302 got entry reference counting is enabled. */
9304 bfd_boolean
9305 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
9307 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
9308 return FALSE;
9310 /* Invoke the regular ELF backend linker to do all the work. */
9311 return bfd_elf_final_link (abfd, info);
9314 bfd_boolean
9315 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
9317 struct elf_reloc_cookie *rcookie = cookie;
9319 if (rcookie->bad_symtab)
9320 rcookie->rel = rcookie->rels;
9322 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9324 unsigned long r_symndx;
9326 if (! rcookie->bad_symtab)
9327 if (rcookie->rel->r_offset > offset)
9328 return FALSE;
9329 if (rcookie->rel->r_offset != offset)
9330 continue;
9332 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9333 if (r_symndx == SHN_UNDEF)
9334 return TRUE;
9336 if (r_symndx >= rcookie->locsymcount
9337 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9339 struct elf_link_hash_entry *h;
9341 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9343 while (h->root.type == bfd_link_hash_indirect
9344 || h->root.type == bfd_link_hash_warning)
9345 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9347 if ((h->root.type == bfd_link_hash_defined
9348 || h->root.type == bfd_link_hash_defweak)
9349 && elf_discarded_section (h->root.u.def.section))
9350 return TRUE;
9351 else
9352 return FALSE;
9354 else
9356 /* It's not a relocation against a global symbol,
9357 but it could be a relocation against a local
9358 symbol for a discarded section. */
9359 asection *isec;
9360 Elf_Internal_Sym *isym;
9362 /* Need to: get the symbol; get the section. */
9363 isym = &rcookie->locsyms[r_symndx];
9364 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9366 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9367 if (isec != NULL && elf_discarded_section (isec))
9368 return TRUE;
9371 return FALSE;
9373 return FALSE;
9376 /* Discard unneeded references to discarded sections.
9377 Returns TRUE if any section's size was changed. */
9378 /* This function assumes that the relocations are in sorted order,
9379 which is true for all known assemblers. */
9381 bfd_boolean
9382 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9384 struct elf_reloc_cookie cookie;
9385 asection *stab, *eh;
9386 Elf_Internal_Shdr *symtab_hdr;
9387 const struct elf_backend_data *bed;
9388 bfd *abfd;
9389 unsigned int count;
9390 bfd_boolean ret = FALSE;
9392 if (info->traditional_format
9393 || !is_elf_hash_table (info->hash))
9394 return FALSE;
9396 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9398 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9399 continue;
9401 bed = get_elf_backend_data (abfd);
9403 if ((abfd->flags & DYNAMIC) != 0)
9404 continue;
9406 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9407 if (info->relocatable
9408 || (eh != NULL
9409 && (eh->size == 0
9410 || bfd_is_abs_section (eh->output_section))))
9411 eh = NULL;
9413 stab = bfd_get_section_by_name (abfd, ".stab");
9414 if (stab != NULL
9415 && (stab->size == 0
9416 || bfd_is_abs_section (stab->output_section)
9417 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9418 stab = NULL;
9420 if (stab == NULL
9421 && eh == NULL
9422 && bed->elf_backend_discard_info == NULL)
9423 continue;
9425 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9426 cookie.abfd = abfd;
9427 cookie.sym_hashes = elf_sym_hashes (abfd);
9428 cookie.bad_symtab = elf_bad_symtab (abfd);
9429 if (cookie.bad_symtab)
9431 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9432 cookie.extsymoff = 0;
9434 else
9436 cookie.locsymcount = symtab_hdr->sh_info;
9437 cookie.extsymoff = symtab_hdr->sh_info;
9440 if (bed->s->arch_size == 32)
9441 cookie.r_sym_shift = 8;
9442 else
9443 cookie.r_sym_shift = 32;
9445 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9446 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9448 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9449 cookie.locsymcount, 0,
9450 NULL, NULL, NULL);
9451 if (cookie.locsyms == NULL)
9452 return FALSE;
9455 if (stab != NULL)
9457 cookie.rels = NULL;
9458 count = stab->reloc_count;
9459 if (count != 0)
9460 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9461 info->keep_memory);
9462 if (cookie.rels != NULL)
9464 cookie.rel = cookie.rels;
9465 cookie.relend = cookie.rels;
9466 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9467 if (_bfd_discard_section_stabs (abfd, stab,
9468 elf_section_data (stab)->sec_info,
9469 bfd_elf_reloc_symbol_deleted_p,
9470 &cookie))
9471 ret = TRUE;
9472 if (elf_section_data (stab)->relocs != cookie.rels)
9473 free (cookie.rels);
9477 if (eh != NULL)
9479 cookie.rels = NULL;
9480 count = eh->reloc_count;
9481 if (count != 0)
9482 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9483 info->keep_memory);
9484 cookie.rel = cookie.rels;
9485 cookie.relend = cookie.rels;
9486 if (cookie.rels != NULL)
9487 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9489 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9490 bfd_elf_reloc_symbol_deleted_p,
9491 &cookie))
9492 ret = TRUE;
9494 if (cookie.rels != NULL
9495 && elf_section_data (eh)->relocs != cookie.rels)
9496 free (cookie.rels);
9499 if (bed->elf_backend_discard_info != NULL
9500 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9501 ret = TRUE;
9503 if (cookie.locsyms != NULL
9504 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9506 if (! info->keep_memory)
9507 free (cookie.locsyms);
9508 else
9509 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9513 if (info->eh_frame_hdr
9514 && !info->relocatable
9515 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9516 ret = TRUE;
9518 return ret;
9521 void
9522 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9524 flagword flags;
9525 const char *name, *p;
9526 struct bfd_section_already_linked *l;
9527 struct bfd_section_already_linked_hash_entry *already_linked_list;
9528 asection *group;
9530 /* A single member comdat group section may be discarded by a
9531 linkonce section. See below. */
9532 if (sec->output_section == bfd_abs_section_ptr)
9533 return;
9535 flags = sec->flags;
9537 /* Check if it belongs to a section group. */
9538 group = elf_sec_group (sec);
9540 /* Return if it isn't a linkonce section nor a member of a group. A
9541 comdat group section also has SEC_LINK_ONCE set. */
9542 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9543 return;
9545 if (group)
9547 /* If this is the member of a single member comdat group, check if
9548 the group should be discarded. */
9549 if (elf_next_in_group (sec) == sec
9550 && (group->flags & SEC_LINK_ONCE) != 0)
9551 sec = group;
9552 else
9553 return;
9556 /* FIXME: When doing a relocatable link, we may have trouble
9557 copying relocations in other sections that refer to local symbols
9558 in the section being discarded. Those relocations will have to
9559 be converted somehow; as of this writing I'm not sure that any of
9560 the backends handle that correctly.
9562 It is tempting to instead not discard link once sections when
9563 doing a relocatable link (technically, they should be discarded
9564 whenever we are building constructors). However, that fails,
9565 because the linker winds up combining all the link once sections
9566 into a single large link once section, which defeats the purpose
9567 of having link once sections in the first place.
9569 Also, not merging link once sections in a relocatable link
9570 causes trouble for MIPS ELF, which relies on link once semantics
9571 to handle the .reginfo section correctly. */
9573 name = bfd_get_section_name (abfd, sec);
9575 if (strncmp (name, ".gnu.linkonce.", sizeof (".gnu.linkonce.") - 1) == 0
9576 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
9577 p++;
9578 else
9579 p = name;
9581 already_linked_list = bfd_section_already_linked_table_lookup (p);
9583 for (l = already_linked_list->entry; l != NULL; l = l->next)
9585 /* We may have 3 different sections on the list: group section,
9586 comdat section and linkonce section. SEC may be a linkonce or
9587 group section. We match a group section with a group section,
9588 a linkonce section with a linkonce section, and ignore comdat
9589 section. */
9590 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9591 && strcmp (name, l->sec->name) == 0
9592 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9594 /* The section has already been linked. See if we should
9595 issue a warning. */
9596 switch (flags & SEC_LINK_DUPLICATES)
9598 default:
9599 abort ();
9601 case SEC_LINK_DUPLICATES_DISCARD:
9602 break;
9604 case SEC_LINK_DUPLICATES_ONE_ONLY:
9605 (*_bfd_error_handler)
9606 (_("%B: ignoring duplicate section `%A'\n"),
9607 abfd, sec);
9608 break;
9610 case SEC_LINK_DUPLICATES_SAME_SIZE:
9611 if (sec->size != l->sec->size)
9612 (*_bfd_error_handler)
9613 (_("%B: duplicate section `%A' has different size\n"),
9614 abfd, sec);
9615 break;
9617 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
9618 if (sec->size != l->sec->size)
9619 (*_bfd_error_handler)
9620 (_("%B: duplicate section `%A' has different size\n"),
9621 abfd, sec);
9622 else if (sec->size != 0)
9624 bfd_byte *sec_contents, *l_sec_contents;
9626 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
9627 (*_bfd_error_handler)
9628 (_("%B: warning: could not read contents of section `%A'\n"),
9629 abfd, sec);
9630 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
9631 &l_sec_contents))
9632 (*_bfd_error_handler)
9633 (_("%B: warning: could not read contents of section `%A'\n"),
9634 l->sec->owner, l->sec);
9635 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
9636 (*_bfd_error_handler)
9637 (_("%B: warning: duplicate section `%A' has different contents\n"),
9638 abfd, sec);
9640 if (sec_contents)
9641 free (sec_contents);
9642 if (l_sec_contents)
9643 free (l_sec_contents);
9645 break;
9648 /* Set the output_section field so that lang_add_section
9649 does not create a lang_input_section structure for this
9650 section. Since there might be a symbol in the section
9651 being discarded, we must retain a pointer to the section
9652 which we are really going to use. */
9653 sec->output_section = bfd_abs_section_ptr;
9654 sec->kept_section = l->sec;
9656 if (flags & SEC_GROUP)
9658 asection *first = elf_next_in_group (sec);
9659 asection *s = first;
9661 while (s != NULL)
9663 s->output_section = bfd_abs_section_ptr;
9664 /* Record which group discards it. */
9665 s->kept_section = l->sec;
9666 s = elf_next_in_group (s);
9667 /* These lists are circular. */
9668 if (s == first)
9669 break;
9673 return;
9677 if (group)
9679 /* If this is the member of a single member comdat group and the
9680 group hasn't be discarded, we check if it matches a linkonce
9681 section. We only record the discarded comdat group. Otherwise
9682 the undiscarded group will be discarded incorrectly later since
9683 itself has been recorded. */
9684 for (l = already_linked_list->entry; l != NULL; l = l->next)
9685 if ((l->sec->flags & SEC_GROUP) == 0
9686 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9687 && bfd_elf_match_symbols_in_sections (l->sec,
9688 elf_next_in_group (sec)))
9690 elf_next_in_group (sec)->output_section = bfd_abs_section_ptr;
9691 elf_next_in_group (sec)->kept_section = l->sec;
9692 group->output_section = bfd_abs_section_ptr;
9693 break;
9695 if (l == NULL)
9696 return;
9698 else
9699 /* There is no direct match. But for linkonce section, we should
9700 check if there is a match with comdat group member. We always
9701 record the linkonce section, discarded or not. */
9702 for (l = already_linked_list->entry; l != NULL; l = l->next)
9703 if (l->sec->flags & SEC_GROUP)
9705 asection *first = elf_next_in_group (l->sec);
9707 if (first != NULL
9708 && elf_next_in_group (first) == first
9709 && bfd_elf_match_symbols_in_sections (first, sec))
9711 sec->output_section = bfd_abs_section_ptr;
9712 sec->kept_section = l->sec;
9713 break;
9717 /* This is the first section with this name. Record it. */
9718 bfd_section_already_linked_table_insert (already_linked_list, sec);