Oops - forgot one place where -K is documented.
[binutils.git] / bfd / elflink.c
blob017ebe436a9ce80dd2702709a8bcaeae998c6efa
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 static unsigned long
711 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
712 struct bfd_link_info *info,
713 unsigned long *section_sym_count)
715 unsigned long dynsymcount = 0;
717 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
719 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
720 asection *p;
721 for (p = output_bfd->sections; p ; p = p->next)
722 if ((p->flags & SEC_EXCLUDE) == 0
723 && (p->flags & SEC_ALLOC) != 0
724 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
725 elf_section_data (p)->dynindx = ++dynsymcount;
727 *section_sym_count = dynsymcount;
729 elf_link_hash_traverse (elf_hash_table (info),
730 elf_link_renumber_local_hash_table_dynsyms,
731 &dynsymcount);
733 if (elf_hash_table (info)->dynlocal)
735 struct elf_link_local_dynamic_entry *p;
736 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
737 p->dynindx = ++dynsymcount;
740 elf_link_hash_traverse (elf_hash_table (info),
741 elf_link_renumber_hash_table_dynsyms,
742 &dynsymcount);
744 /* There is an unused NULL entry at the head of the table which
745 we must account for in our count. Unless there weren't any
746 symbols, which means we'll have no table at all. */
747 if (dynsymcount != 0)
748 ++dynsymcount;
750 return elf_hash_table (info)->dynsymcount = dynsymcount;
753 /* This function is called when we want to define a new symbol. It
754 handles the various cases which arise when we find a definition in
755 a dynamic object, or when there is already a definition in a
756 dynamic object. The new symbol is described by NAME, SYM, PSEC,
757 and PVALUE. We set SYM_HASH to the hash table entry. We set
758 OVERRIDE if the old symbol is overriding a new definition. We set
759 TYPE_CHANGE_OK if it is OK for the type to change. We set
760 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
761 change, we mean that we shouldn't warn if the type or size does
762 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
763 object is overridden by a regular object. */
765 bfd_boolean
766 _bfd_elf_merge_symbol (bfd *abfd,
767 struct bfd_link_info *info,
768 const char *name,
769 Elf_Internal_Sym *sym,
770 asection **psec,
771 bfd_vma *pvalue,
772 unsigned int *pold_alignment,
773 struct elf_link_hash_entry **sym_hash,
774 bfd_boolean *skip,
775 bfd_boolean *override,
776 bfd_boolean *type_change_ok,
777 bfd_boolean *size_change_ok)
779 asection *sec, *oldsec;
780 struct elf_link_hash_entry *h;
781 struct elf_link_hash_entry *flip;
782 int bind;
783 bfd *oldbfd;
784 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
785 bfd_boolean newweak, oldweak;
787 *skip = FALSE;
788 *override = FALSE;
790 sec = *psec;
791 bind = ELF_ST_BIND (sym->st_info);
793 if (! bfd_is_und_section (sec))
794 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
795 else
796 h = ((struct elf_link_hash_entry *)
797 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
798 if (h == NULL)
799 return FALSE;
800 *sym_hash = h;
802 /* This code is for coping with dynamic objects, and is only useful
803 if we are doing an ELF link. */
804 if (info->hash->creator != abfd->xvec)
805 return TRUE;
807 /* For merging, we only care about real symbols. */
809 while (h->root.type == bfd_link_hash_indirect
810 || h->root.type == bfd_link_hash_warning)
811 h = (struct elf_link_hash_entry *) h->root.u.i.link;
813 /* If we just created the symbol, mark it as being an ELF symbol.
814 Other than that, there is nothing to do--there is no merge issue
815 with a newly defined symbol--so we just return. */
817 if (h->root.type == bfd_link_hash_new)
819 h->non_elf = 0;
820 return TRUE;
823 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
824 existing symbol. */
826 switch (h->root.type)
828 default:
829 oldbfd = NULL;
830 oldsec = NULL;
831 break;
833 case bfd_link_hash_undefined:
834 case bfd_link_hash_undefweak:
835 oldbfd = h->root.u.undef.abfd;
836 oldsec = NULL;
837 break;
839 case bfd_link_hash_defined:
840 case bfd_link_hash_defweak:
841 oldbfd = h->root.u.def.section->owner;
842 oldsec = h->root.u.def.section;
843 break;
845 case bfd_link_hash_common:
846 oldbfd = h->root.u.c.p->section->owner;
847 oldsec = h->root.u.c.p->section;
848 break;
851 /* In cases involving weak versioned symbols, we may wind up trying
852 to merge a symbol with itself. Catch that here, to avoid the
853 confusion that results if we try to override a symbol with
854 itself. The additional tests catch cases like
855 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
856 dynamic object, which we do want to handle here. */
857 if (abfd == oldbfd
858 && ((abfd->flags & DYNAMIC) == 0
859 || !h->def_regular))
860 return TRUE;
862 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
863 respectively, is from a dynamic object. */
865 if ((abfd->flags & DYNAMIC) != 0)
866 newdyn = TRUE;
867 else
868 newdyn = FALSE;
870 if (oldbfd != NULL)
871 olddyn = (oldbfd->flags & DYNAMIC) != 0;
872 else
874 asection *hsec;
876 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
877 indices used by MIPS ELF. */
878 switch (h->root.type)
880 default:
881 hsec = NULL;
882 break;
884 case bfd_link_hash_defined:
885 case bfd_link_hash_defweak:
886 hsec = h->root.u.def.section;
887 break;
889 case bfd_link_hash_common:
890 hsec = h->root.u.c.p->section;
891 break;
894 if (hsec == NULL)
895 olddyn = FALSE;
896 else
897 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
900 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
901 respectively, appear to be a definition rather than reference. */
903 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
904 newdef = FALSE;
905 else
906 newdef = TRUE;
908 if (h->root.type == bfd_link_hash_undefined
909 || h->root.type == bfd_link_hash_undefweak
910 || h->root.type == bfd_link_hash_common)
911 olddef = FALSE;
912 else
913 olddef = TRUE;
915 /* Check TLS symbol. */
916 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
917 && ELF_ST_TYPE (sym->st_info) != h->type)
919 bfd *ntbfd, *tbfd;
920 bfd_boolean ntdef, tdef;
921 asection *ntsec, *tsec;
923 if (h->type == STT_TLS)
925 ntbfd = abfd;
926 ntsec = sec;
927 ntdef = newdef;
928 tbfd = oldbfd;
929 tsec = oldsec;
930 tdef = olddef;
932 else
934 ntbfd = oldbfd;
935 ntsec = oldsec;
936 ntdef = olddef;
937 tbfd = abfd;
938 tsec = sec;
939 tdef = newdef;
942 if (tdef && ntdef)
943 (*_bfd_error_handler)
944 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
945 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
946 else if (!tdef && !ntdef)
947 (*_bfd_error_handler)
948 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
949 tbfd, ntbfd, h->root.root.string);
950 else if (tdef)
951 (*_bfd_error_handler)
952 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
953 tbfd, tsec, ntbfd, h->root.root.string);
954 else
955 (*_bfd_error_handler)
956 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
957 tbfd, ntbfd, ntsec, h->root.root.string);
959 bfd_set_error (bfd_error_bad_value);
960 return FALSE;
963 /* We need to remember if a symbol has a definition in a dynamic
964 object or is weak in all dynamic objects. Internal and hidden
965 visibility will make it unavailable to dynamic objects. */
966 if (newdyn && !h->dynamic_def)
968 if (!bfd_is_und_section (sec))
969 h->dynamic_def = 1;
970 else
972 /* Check if this symbol is weak in all dynamic objects. If it
973 is the first time we see it in a dynamic object, we mark
974 if it is weak. Otherwise, we clear it. */
975 if (!h->ref_dynamic)
977 if (bind == STB_WEAK)
978 h->dynamic_weak = 1;
980 else if (bind != STB_WEAK)
981 h->dynamic_weak = 0;
985 /* If the old symbol has non-default visibility, we ignore the new
986 definition from a dynamic object. */
987 if (newdyn
988 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
989 && !bfd_is_und_section (sec))
991 *skip = TRUE;
992 /* Make sure this symbol is dynamic. */
993 h->ref_dynamic = 1;
994 /* A protected symbol has external availability. Make sure it is
995 recorded as dynamic.
997 FIXME: Should we check type and size for protected symbol? */
998 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
999 return bfd_elf_link_record_dynamic_symbol (info, h);
1000 else
1001 return TRUE;
1003 else if (!newdyn
1004 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1005 && h->def_dynamic)
1007 /* If the new symbol with non-default visibility comes from a
1008 relocatable file and the old definition comes from a dynamic
1009 object, we remove the old definition. */
1010 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1011 h = *sym_hash;
1013 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1014 && bfd_is_und_section (sec))
1016 /* If the new symbol is undefined and the old symbol was
1017 also undefined before, we need to make sure
1018 _bfd_generic_link_add_one_symbol doesn't mess
1019 up the linker hash table undefs list. Since the old
1020 definition came from a dynamic object, it is still on the
1021 undefs list. */
1022 h->root.type = bfd_link_hash_undefined;
1023 h->root.u.undef.abfd = abfd;
1025 else
1027 h->root.type = bfd_link_hash_new;
1028 h->root.u.undef.abfd = NULL;
1031 if (h->def_dynamic)
1033 h->def_dynamic = 0;
1034 h->ref_dynamic = 1;
1035 h->dynamic_def = 1;
1037 /* FIXME: Should we check type and size for protected symbol? */
1038 h->size = 0;
1039 h->type = 0;
1040 return TRUE;
1043 /* Differentiate strong and weak symbols. */
1044 newweak = bind == STB_WEAK;
1045 oldweak = (h->root.type == bfd_link_hash_defweak
1046 || h->root.type == bfd_link_hash_undefweak);
1048 /* If a new weak symbol definition comes from a regular file and the
1049 old symbol comes from a dynamic library, we treat the new one as
1050 strong. Similarly, an old weak symbol definition from a regular
1051 file is treated as strong when the new symbol comes from a dynamic
1052 library. Further, an old weak symbol from a dynamic library is
1053 treated as strong if the new symbol is from a dynamic library.
1054 This reflects the way glibc's ld.so works.
1056 Do this before setting *type_change_ok or *size_change_ok so that
1057 we warn properly when dynamic library symbols are overridden. */
1059 if (newdef && !newdyn && olddyn)
1060 newweak = FALSE;
1061 if (olddef && newdyn)
1062 oldweak = FALSE;
1064 /* It's OK to change the type if either the existing symbol or the
1065 new symbol is weak. A type change is also OK if the old symbol
1066 is undefined and the new symbol is defined. */
1068 if (oldweak
1069 || newweak
1070 || (newdef
1071 && h->root.type == bfd_link_hash_undefined))
1072 *type_change_ok = TRUE;
1074 /* It's OK to change the size if either the existing symbol or the
1075 new symbol is weak, or if the old symbol is undefined. */
1077 if (*type_change_ok
1078 || h->root.type == bfd_link_hash_undefined)
1079 *size_change_ok = TRUE;
1081 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1082 symbol, respectively, appears to be a common symbol in a dynamic
1083 object. If a symbol appears in an uninitialized section, and is
1084 not weak, and is not a function, then it may be a common symbol
1085 which was resolved when the dynamic object was created. We want
1086 to treat such symbols specially, because they raise special
1087 considerations when setting the symbol size: if the symbol
1088 appears as a common symbol in a regular object, and the size in
1089 the regular object is larger, we must make sure that we use the
1090 larger size. This problematic case can always be avoided in C,
1091 but it must be handled correctly when using Fortran shared
1092 libraries.
1094 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1095 likewise for OLDDYNCOMMON and OLDDEF.
1097 Note that this test is just a heuristic, and that it is quite
1098 possible to have an uninitialized symbol in a shared object which
1099 is really a definition, rather than a common symbol. This could
1100 lead to some minor confusion when the symbol really is a common
1101 symbol in some regular object. However, I think it will be
1102 harmless. */
1104 if (newdyn
1105 && newdef
1106 && !newweak
1107 && (sec->flags & SEC_ALLOC) != 0
1108 && (sec->flags & SEC_LOAD) == 0
1109 && sym->st_size > 0
1110 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1111 newdyncommon = TRUE;
1112 else
1113 newdyncommon = FALSE;
1115 if (olddyn
1116 && olddef
1117 && h->root.type == bfd_link_hash_defined
1118 && h->def_dynamic
1119 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1120 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1121 && h->size > 0
1122 && h->type != STT_FUNC)
1123 olddyncommon = TRUE;
1124 else
1125 olddyncommon = FALSE;
1127 /* If both the old and the new symbols look like common symbols in a
1128 dynamic object, set the size of the symbol to the larger of the
1129 two. */
1131 if (olddyncommon
1132 && newdyncommon
1133 && sym->st_size != h->size)
1135 /* Since we think we have two common symbols, issue a multiple
1136 common warning if desired. Note that we only warn if the
1137 size is different. If the size is the same, we simply let
1138 the old symbol override the new one as normally happens with
1139 symbols defined in dynamic objects. */
1141 if (! ((*info->callbacks->multiple_common)
1142 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1143 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1144 return FALSE;
1146 if (sym->st_size > h->size)
1147 h->size = sym->st_size;
1149 *size_change_ok = TRUE;
1152 /* If we are looking at a dynamic object, and we have found a
1153 definition, we need to see if the symbol was already defined by
1154 some other object. If so, we want to use the existing
1155 definition, and we do not want to report a multiple symbol
1156 definition error; we do this by clobbering *PSEC to be
1157 bfd_und_section_ptr.
1159 We treat a common symbol as a definition if the symbol in the
1160 shared library is a function, since common symbols always
1161 represent variables; this can cause confusion in principle, but
1162 any such confusion would seem to indicate an erroneous program or
1163 shared library. We also permit a common symbol in a regular
1164 object to override a weak symbol in a shared object. */
1166 if (newdyn
1167 && newdef
1168 && (olddef
1169 || (h->root.type == bfd_link_hash_common
1170 && (newweak
1171 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1173 *override = TRUE;
1174 newdef = FALSE;
1175 newdyncommon = FALSE;
1177 *psec = sec = bfd_und_section_ptr;
1178 *size_change_ok = TRUE;
1180 /* If we get here when the old symbol is a common symbol, then
1181 we are explicitly letting it override a weak symbol or
1182 function in a dynamic object, and we don't want to warn about
1183 a type change. If the old symbol is a defined symbol, a type
1184 change warning may still be appropriate. */
1186 if (h->root.type == bfd_link_hash_common)
1187 *type_change_ok = TRUE;
1190 /* Handle the special case of an old common symbol merging with a
1191 new symbol which looks like a common symbol in a shared object.
1192 We change *PSEC and *PVALUE to make the new symbol look like a
1193 common symbol, and let _bfd_generic_link_add_one_symbol will do
1194 the right thing. */
1196 if (newdyncommon
1197 && h->root.type == bfd_link_hash_common)
1199 *override = TRUE;
1200 newdef = FALSE;
1201 newdyncommon = FALSE;
1202 *pvalue = sym->st_size;
1203 *psec = sec = bfd_com_section_ptr;
1204 *size_change_ok = TRUE;
1207 /* If the old symbol is from a dynamic object, and the new symbol is
1208 a definition which is not from a dynamic object, then the new
1209 symbol overrides the old symbol. Symbols from regular files
1210 always take precedence over symbols from dynamic objects, even if
1211 they are defined after the dynamic object in the link.
1213 As above, we again permit a common symbol in a regular object to
1214 override a definition in a shared object if the shared object
1215 symbol is a function or is weak. */
1217 flip = NULL;
1218 if (!newdyn
1219 && (newdef
1220 || (bfd_is_com_section (sec)
1221 && (oldweak
1222 || h->type == STT_FUNC)))
1223 && olddyn
1224 && olddef
1225 && h->def_dynamic)
1227 /* Change the hash table entry to undefined, and let
1228 _bfd_generic_link_add_one_symbol do the right thing with the
1229 new definition. */
1231 h->root.type = bfd_link_hash_undefined;
1232 h->root.u.undef.abfd = h->root.u.def.section->owner;
1233 *size_change_ok = TRUE;
1235 olddef = FALSE;
1236 olddyncommon = FALSE;
1238 /* We again permit a type change when a common symbol may be
1239 overriding a function. */
1241 if (bfd_is_com_section (sec))
1242 *type_change_ok = TRUE;
1244 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1245 flip = *sym_hash;
1246 else
1247 /* This union may have been set to be non-NULL when this symbol
1248 was seen in a dynamic object. We must force the union to be
1249 NULL, so that it is correct for a regular symbol. */
1250 h->verinfo.vertree = NULL;
1253 /* Handle the special case of a new common symbol merging with an
1254 old symbol that looks like it might be a common symbol defined in
1255 a shared object. Note that we have already handled the case in
1256 which a new common symbol should simply override the definition
1257 in the shared library. */
1259 if (! newdyn
1260 && bfd_is_com_section (sec)
1261 && olddyncommon)
1263 /* It would be best if we could set the hash table entry to a
1264 common symbol, but we don't know what to use for the section
1265 or the alignment. */
1266 if (! ((*info->callbacks->multiple_common)
1267 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1268 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1269 return FALSE;
1271 /* If the presumed common symbol in the dynamic object is
1272 larger, pretend that the new symbol has its size. */
1274 if (h->size > *pvalue)
1275 *pvalue = h->size;
1277 /* We need to remember the alignment required by the symbol
1278 in the dynamic object. */
1279 BFD_ASSERT (pold_alignment);
1280 *pold_alignment = h->root.u.def.section->alignment_power;
1282 olddef = FALSE;
1283 olddyncommon = FALSE;
1285 h->root.type = bfd_link_hash_undefined;
1286 h->root.u.undef.abfd = h->root.u.def.section->owner;
1288 *size_change_ok = TRUE;
1289 *type_change_ok = TRUE;
1291 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1292 flip = *sym_hash;
1293 else
1294 h->verinfo.vertree = NULL;
1297 if (flip != NULL)
1299 /* Handle the case where we had a versioned symbol in a dynamic
1300 library and now find a definition in a normal object. In this
1301 case, we make the versioned symbol point to the normal one. */
1302 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1303 flip->root.type = h->root.type;
1304 h->root.type = bfd_link_hash_indirect;
1305 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1306 (*bed->elf_backend_copy_indirect_symbol) (bed, flip, h);
1307 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1308 if (h->def_dynamic)
1310 h->def_dynamic = 0;
1311 flip->ref_dynamic = 1;
1315 return TRUE;
1318 /* This function is called to create an indirect symbol from the
1319 default for the symbol with the default version if needed. The
1320 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1321 set DYNSYM if the new indirect symbol is dynamic. */
1323 bfd_boolean
1324 _bfd_elf_add_default_symbol (bfd *abfd,
1325 struct bfd_link_info *info,
1326 struct elf_link_hash_entry *h,
1327 const char *name,
1328 Elf_Internal_Sym *sym,
1329 asection **psec,
1330 bfd_vma *value,
1331 bfd_boolean *dynsym,
1332 bfd_boolean override)
1334 bfd_boolean type_change_ok;
1335 bfd_boolean size_change_ok;
1336 bfd_boolean skip;
1337 char *shortname;
1338 struct elf_link_hash_entry *hi;
1339 struct bfd_link_hash_entry *bh;
1340 const struct elf_backend_data *bed;
1341 bfd_boolean collect;
1342 bfd_boolean dynamic;
1343 char *p;
1344 size_t len, shortlen;
1345 asection *sec;
1347 /* If this symbol has a version, and it is the default version, we
1348 create an indirect symbol from the default name to the fully
1349 decorated name. This will cause external references which do not
1350 specify a version to be bound to this version of the symbol. */
1351 p = strchr (name, ELF_VER_CHR);
1352 if (p == NULL || p[1] != ELF_VER_CHR)
1353 return TRUE;
1355 if (override)
1357 /* We are overridden by an old definition. We need to check if we
1358 need to create the indirect symbol from the default name. */
1359 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1360 FALSE, FALSE);
1361 BFD_ASSERT (hi != NULL);
1362 if (hi == h)
1363 return TRUE;
1364 while (hi->root.type == bfd_link_hash_indirect
1365 || hi->root.type == bfd_link_hash_warning)
1367 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1368 if (hi == h)
1369 return TRUE;
1373 bed = get_elf_backend_data (abfd);
1374 collect = bed->collect;
1375 dynamic = (abfd->flags & DYNAMIC) != 0;
1377 shortlen = p - name;
1378 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1379 if (shortname == NULL)
1380 return FALSE;
1381 memcpy (shortname, name, shortlen);
1382 shortname[shortlen] = '\0';
1384 /* We are going to create a new symbol. Merge it with any existing
1385 symbol with this name. For the purposes of the merge, act as
1386 though we were defining the symbol we just defined, although we
1387 actually going to define an indirect symbol. */
1388 type_change_ok = FALSE;
1389 size_change_ok = FALSE;
1390 sec = *psec;
1391 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1392 NULL, &hi, &skip, &override,
1393 &type_change_ok, &size_change_ok))
1394 return FALSE;
1396 if (skip)
1397 goto nondefault;
1399 if (! override)
1401 bh = &hi->root;
1402 if (! (_bfd_generic_link_add_one_symbol
1403 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1404 0, name, FALSE, collect, &bh)))
1405 return FALSE;
1406 hi = (struct elf_link_hash_entry *) bh;
1408 else
1410 /* In this case the symbol named SHORTNAME is overriding the
1411 indirect symbol we want to add. We were planning on making
1412 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1413 is the name without a version. NAME is the fully versioned
1414 name, and it is the default version.
1416 Overriding means that we already saw a definition for the
1417 symbol SHORTNAME in a regular object, and it is overriding
1418 the symbol defined in the dynamic object.
1420 When this happens, we actually want to change NAME, the
1421 symbol we just added, to refer to SHORTNAME. This will cause
1422 references to NAME in the shared object to become references
1423 to SHORTNAME in the regular object. This is what we expect
1424 when we override a function in a shared object: that the
1425 references in the shared object will be mapped to the
1426 definition in the regular object. */
1428 while (hi->root.type == bfd_link_hash_indirect
1429 || hi->root.type == bfd_link_hash_warning)
1430 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1432 h->root.type = bfd_link_hash_indirect;
1433 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1434 if (h->def_dynamic)
1436 h->def_dynamic = 0;
1437 hi->ref_dynamic = 1;
1438 if (hi->ref_regular
1439 || hi->def_regular)
1441 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1442 return FALSE;
1446 /* Now set HI to H, so that the following code will set the
1447 other fields correctly. */
1448 hi = h;
1451 /* If there is a duplicate definition somewhere, then HI may not
1452 point to an indirect symbol. We will have reported an error to
1453 the user in that case. */
1455 if (hi->root.type == bfd_link_hash_indirect)
1457 struct elf_link_hash_entry *ht;
1459 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1460 (*bed->elf_backend_copy_indirect_symbol) (bed, ht, hi);
1462 /* See if the new flags lead us to realize that the symbol must
1463 be dynamic. */
1464 if (! *dynsym)
1466 if (! dynamic)
1468 if (info->shared
1469 || hi->ref_dynamic)
1470 *dynsym = TRUE;
1472 else
1474 if (hi->ref_regular)
1475 *dynsym = TRUE;
1480 /* We also need to define an indirection from the nondefault version
1481 of the symbol. */
1483 nondefault:
1484 len = strlen (name);
1485 shortname = bfd_hash_allocate (&info->hash->table, len);
1486 if (shortname == NULL)
1487 return FALSE;
1488 memcpy (shortname, name, shortlen);
1489 memcpy (shortname + shortlen, p + 1, len - shortlen);
1491 /* Once again, merge with any existing symbol. */
1492 type_change_ok = FALSE;
1493 size_change_ok = FALSE;
1494 sec = *psec;
1495 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1496 NULL, &hi, &skip, &override,
1497 &type_change_ok, &size_change_ok))
1498 return FALSE;
1500 if (skip)
1501 return TRUE;
1503 if (override)
1505 /* Here SHORTNAME is a versioned name, so we don't expect to see
1506 the type of override we do in the case above unless it is
1507 overridden by a versioned definition. */
1508 if (hi->root.type != bfd_link_hash_defined
1509 && hi->root.type != bfd_link_hash_defweak)
1510 (*_bfd_error_handler)
1511 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1512 abfd, shortname);
1514 else
1516 bh = &hi->root;
1517 if (! (_bfd_generic_link_add_one_symbol
1518 (info, abfd, shortname, BSF_INDIRECT,
1519 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1520 return FALSE;
1521 hi = (struct elf_link_hash_entry *) bh;
1523 /* If there is a duplicate definition somewhere, then HI may not
1524 point to an indirect symbol. We will have reported an error
1525 to the user in that case. */
1527 if (hi->root.type == bfd_link_hash_indirect)
1529 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
1531 /* See if the new flags lead us to realize that the symbol
1532 must be dynamic. */
1533 if (! *dynsym)
1535 if (! dynamic)
1537 if (info->shared
1538 || hi->ref_dynamic)
1539 *dynsym = TRUE;
1541 else
1543 if (hi->ref_regular)
1544 *dynsym = TRUE;
1550 return TRUE;
1553 /* This routine is used to export all defined symbols into the dynamic
1554 symbol table. It is called via elf_link_hash_traverse. */
1556 bfd_boolean
1557 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1559 struct elf_info_failed *eif = data;
1561 /* Ignore indirect symbols. These are added by the versioning code. */
1562 if (h->root.type == bfd_link_hash_indirect)
1563 return TRUE;
1565 if (h->root.type == bfd_link_hash_warning)
1566 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1568 if (h->dynindx == -1
1569 && (h->def_regular
1570 || h->ref_regular))
1572 struct bfd_elf_version_tree *t;
1573 struct bfd_elf_version_expr *d;
1575 for (t = eif->verdefs; t != NULL; t = t->next)
1577 if (t->globals.list != NULL)
1579 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1580 if (d != NULL)
1581 goto doit;
1584 if (t->locals.list != NULL)
1586 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1587 if (d != NULL)
1588 return TRUE;
1592 if (!eif->verdefs)
1594 doit:
1595 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1597 eif->failed = TRUE;
1598 return FALSE;
1603 return TRUE;
1606 /* Look through the symbols which are defined in other shared
1607 libraries and referenced here. Update the list of version
1608 dependencies. This will be put into the .gnu.version_r section.
1609 This function is called via elf_link_hash_traverse. */
1611 bfd_boolean
1612 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1613 void *data)
1615 struct elf_find_verdep_info *rinfo = data;
1616 Elf_Internal_Verneed *t;
1617 Elf_Internal_Vernaux *a;
1618 bfd_size_type amt;
1620 if (h->root.type == bfd_link_hash_warning)
1621 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1623 /* We only care about symbols defined in shared objects with version
1624 information. */
1625 if (!h->def_dynamic
1626 || h->def_regular
1627 || h->dynindx == -1
1628 || h->verinfo.verdef == NULL)
1629 return TRUE;
1631 /* See if we already know about this version. */
1632 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1634 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1635 continue;
1637 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1638 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1639 return TRUE;
1641 break;
1644 /* This is a new version. Add it to tree we are building. */
1646 if (t == NULL)
1648 amt = sizeof *t;
1649 t = bfd_zalloc (rinfo->output_bfd, amt);
1650 if (t == NULL)
1652 rinfo->failed = TRUE;
1653 return FALSE;
1656 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1657 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1658 elf_tdata (rinfo->output_bfd)->verref = t;
1661 amt = sizeof *a;
1662 a = bfd_zalloc (rinfo->output_bfd, amt);
1664 /* Note that we are copying a string pointer here, and testing it
1665 above. If bfd_elf_string_from_elf_section is ever changed to
1666 discard the string data when low in memory, this will have to be
1667 fixed. */
1668 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1670 a->vna_flags = h->verinfo.verdef->vd_flags;
1671 a->vna_nextptr = t->vn_auxptr;
1673 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1674 ++rinfo->vers;
1676 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1678 t->vn_auxptr = a;
1680 return TRUE;
1683 /* Figure out appropriate versions for all the symbols. We may not
1684 have the version number script until we have read all of the input
1685 files, so until that point we don't know which symbols should be
1686 local. This function is called via elf_link_hash_traverse. */
1688 bfd_boolean
1689 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1691 struct elf_assign_sym_version_info *sinfo;
1692 struct bfd_link_info *info;
1693 const struct elf_backend_data *bed;
1694 struct elf_info_failed eif;
1695 char *p;
1696 bfd_size_type amt;
1698 sinfo = data;
1699 info = sinfo->info;
1701 if (h->root.type == bfd_link_hash_warning)
1702 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1704 /* Fix the symbol flags. */
1705 eif.failed = FALSE;
1706 eif.info = info;
1707 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1709 if (eif.failed)
1710 sinfo->failed = TRUE;
1711 return FALSE;
1714 /* We only need version numbers for symbols defined in regular
1715 objects. */
1716 if (!h->def_regular)
1717 return TRUE;
1719 bed = get_elf_backend_data (sinfo->output_bfd);
1720 p = strchr (h->root.root.string, ELF_VER_CHR);
1721 if (p != NULL && h->verinfo.vertree == NULL)
1723 struct bfd_elf_version_tree *t;
1724 bfd_boolean hidden;
1726 hidden = TRUE;
1728 /* There are two consecutive ELF_VER_CHR characters if this is
1729 not a hidden symbol. */
1730 ++p;
1731 if (*p == ELF_VER_CHR)
1733 hidden = FALSE;
1734 ++p;
1737 /* If there is no version string, we can just return out. */
1738 if (*p == '\0')
1740 if (hidden)
1741 h->hidden = 1;
1742 return TRUE;
1745 /* Look for the version. If we find it, it is no longer weak. */
1746 for (t = sinfo->verdefs; t != NULL; t = t->next)
1748 if (strcmp (t->name, p) == 0)
1750 size_t len;
1751 char *alc;
1752 struct bfd_elf_version_expr *d;
1754 len = p - h->root.root.string;
1755 alc = bfd_malloc (len);
1756 if (alc == NULL)
1757 return FALSE;
1758 memcpy (alc, h->root.root.string, len - 1);
1759 alc[len - 1] = '\0';
1760 if (alc[len - 2] == ELF_VER_CHR)
1761 alc[len - 2] = '\0';
1763 h->verinfo.vertree = t;
1764 t->used = TRUE;
1765 d = NULL;
1767 if (t->globals.list != NULL)
1768 d = (*t->match) (&t->globals, NULL, alc);
1770 /* See if there is anything to force this symbol to
1771 local scope. */
1772 if (d == NULL && t->locals.list != NULL)
1774 d = (*t->match) (&t->locals, NULL, alc);
1775 if (d != NULL
1776 && h->dynindx != -1
1777 && info->shared
1778 && ! info->export_dynamic)
1779 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1782 free (alc);
1783 break;
1787 /* If we are building an application, we need to create a
1788 version node for this version. */
1789 if (t == NULL && info->executable)
1791 struct bfd_elf_version_tree **pp;
1792 int version_index;
1794 /* If we aren't going to export this symbol, we don't need
1795 to worry about it. */
1796 if (h->dynindx == -1)
1797 return TRUE;
1799 amt = sizeof *t;
1800 t = bfd_zalloc (sinfo->output_bfd, amt);
1801 if (t == NULL)
1803 sinfo->failed = TRUE;
1804 return FALSE;
1807 t->name = p;
1808 t->name_indx = (unsigned int) -1;
1809 t->used = TRUE;
1811 version_index = 1;
1812 /* Don't count anonymous version tag. */
1813 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1814 version_index = 0;
1815 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1816 ++version_index;
1817 t->vernum = version_index;
1819 *pp = t;
1821 h->verinfo.vertree = t;
1823 else if (t == NULL)
1825 /* We could not find the version for a symbol when
1826 generating a shared archive. Return an error. */
1827 (*_bfd_error_handler)
1828 (_("%B: undefined versioned symbol name %s"),
1829 sinfo->output_bfd, h->root.root.string);
1830 bfd_set_error (bfd_error_bad_value);
1831 sinfo->failed = TRUE;
1832 return FALSE;
1835 if (hidden)
1836 h->hidden = 1;
1839 /* If we don't have a version for this symbol, see if we can find
1840 something. */
1841 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1843 struct bfd_elf_version_tree *t;
1844 struct bfd_elf_version_tree *local_ver;
1845 struct bfd_elf_version_expr *d;
1847 /* See if can find what version this symbol is in. If the
1848 symbol is supposed to be local, then don't actually register
1849 it. */
1850 local_ver = NULL;
1851 for (t = sinfo->verdefs; t != NULL; t = t->next)
1853 if (t->globals.list != NULL)
1855 bfd_boolean matched;
1857 matched = FALSE;
1858 d = NULL;
1859 while ((d = (*t->match) (&t->globals, d,
1860 h->root.root.string)) != NULL)
1861 if (d->symver)
1862 matched = TRUE;
1863 else
1865 /* There is a version without definition. Make
1866 the symbol the default definition for this
1867 version. */
1868 h->verinfo.vertree = t;
1869 local_ver = NULL;
1870 d->script = 1;
1871 break;
1873 if (d != NULL)
1874 break;
1875 else if (matched)
1876 /* There is no undefined version for this symbol. Hide the
1877 default one. */
1878 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1881 if (t->locals.list != NULL)
1883 d = NULL;
1884 while ((d = (*t->match) (&t->locals, d,
1885 h->root.root.string)) != NULL)
1887 local_ver = t;
1888 /* If the match is "*", keep looking for a more
1889 explicit, perhaps even global, match.
1890 XXX: Shouldn't this be !d->wildcard instead? */
1891 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1892 break;
1895 if (d != NULL)
1896 break;
1900 if (local_ver != NULL)
1902 h->verinfo.vertree = local_ver;
1903 if (h->dynindx != -1
1904 && info->shared
1905 && ! info->export_dynamic)
1907 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1912 return TRUE;
1915 /* Read and swap the relocs from the section indicated by SHDR. This
1916 may be either a REL or a RELA section. The relocations are
1917 translated into RELA relocations and stored in INTERNAL_RELOCS,
1918 which should have already been allocated to contain enough space.
1919 The EXTERNAL_RELOCS are a buffer where the external form of the
1920 relocations should be stored.
1922 Returns FALSE if something goes wrong. */
1924 static bfd_boolean
1925 elf_link_read_relocs_from_section (bfd *abfd,
1926 asection *sec,
1927 Elf_Internal_Shdr *shdr,
1928 void *external_relocs,
1929 Elf_Internal_Rela *internal_relocs)
1931 const struct elf_backend_data *bed;
1932 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1933 const bfd_byte *erela;
1934 const bfd_byte *erelaend;
1935 Elf_Internal_Rela *irela;
1936 Elf_Internal_Shdr *symtab_hdr;
1937 size_t nsyms;
1939 /* Position ourselves at the start of the section. */
1940 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1941 return FALSE;
1943 /* Read the relocations. */
1944 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1945 return FALSE;
1947 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1948 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1950 bed = get_elf_backend_data (abfd);
1952 /* Convert the external relocations to the internal format. */
1953 if (shdr->sh_entsize == bed->s->sizeof_rel)
1954 swap_in = bed->s->swap_reloc_in;
1955 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1956 swap_in = bed->s->swap_reloca_in;
1957 else
1959 bfd_set_error (bfd_error_wrong_format);
1960 return FALSE;
1963 erela = external_relocs;
1964 erelaend = erela + shdr->sh_size;
1965 irela = internal_relocs;
1966 while (erela < erelaend)
1968 bfd_vma r_symndx;
1970 (*swap_in) (abfd, erela, irela);
1971 r_symndx = ELF32_R_SYM (irela->r_info);
1972 if (bed->s->arch_size == 64)
1973 r_symndx >>= 24;
1974 if ((size_t) r_symndx >= nsyms)
1976 (*_bfd_error_handler)
1977 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
1978 " for offset 0x%lx in section `%A'"),
1979 abfd, sec,
1980 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
1981 bfd_set_error (bfd_error_bad_value);
1982 return FALSE;
1984 irela += bed->s->int_rels_per_ext_rel;
1985 erela += shdr->sh_entsize;
1988 return TRUE;
1991 /* Read and swap the relocs for a section O. They may have been
1992 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
1993 not NULL, they are used as buffers to read into. They are known to
1994 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
1995 the return value is allocated using either malloc or bfd_alloc,
1996 according to the KEEP_MEMORY argument. If O has two relocation
1997 sections (both REL and RELA relocations), then the REL_HDR
1998 relocations will appear first in INTERNAL_RELOCS, followed by the
1999 REL_HDR2 relocations. */
2001 Elf_Internal_Rela *
2002 _bfd_elf_link_read_relocs (bfd *abfd,
2003 asection *o,
2004 void *external_relocs,
2005 Elf_Internal_Rela *internal_relocs,
2006 bfd_boolean keep_memory)
2008 Elf_Internal_Shdr *rel_hdr;
2009 void *alloc1 = NULL;
2010 Elf_Internal_Rela *alloc2 = NULL;
2011 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2013 if (elf_section_data (o)->relocs != NULL)
2014 return elf_section_data (o)->relocs;
2016 if (o->reloc_count == 0)
2017 return NULL;
2019 rel_hdr = &elf_section_data (o)->rel_hdr;
2021 if (internal_relocs == NULL)
2023 bfd_size_type size;
2025 size = o->reloc_count;
2026 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2027 if (keep_memory)
2028 internal_relocs = bfd_alloc (abfd, size);
2029 else
2030 internal_relocs = alloc2 = bfd_malloc (size);
2031 if (internal_relocs == NULL)
2032 goto error_return;
2035 if (external_relocs == NULL)
2037 bfd_size_type size = rel_hdr->sh_size;
2039 if (elf_section_data (o)->rel_hdr2)
2040 size += elf_section_data (o)->rel_hdr2->sh_size;
2041 alloc1 = bfd_malloc (size);
2042 if (alloc1 == NULL)
2043 goto error_return;
2044 external_relocs = alloc1;
2047 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2048 external_relocs,
2049 internal_relocs))
2050 goto error_return;
2051 if (elf_section_data (o)->rel_hdr2
2052 && (!elf_link_read_relocs_from_section
2053 (abfd, o,
2054 elf_section_data (o)->rel_hdr2,
2055 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2056 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2057 * bed->s->int_rels_per_ext_rel))))
2058 goto error_return;
2060 /* Cache the results for next time, if we can. */
2061 if (keep_memory)
2062 elf_section_data (o)->relocs = internal_relocs;
2064 if (alloc1 != NULL)
2065 free (alloc1);
2067 /* Don't free alloc2, since if it was allocated we are passing it
2068 back (under the name of internal_relocs). */
2070 return internal_relocs;
2072 error_return:
2073 if (alloc1 != NULL)
2074 free (alloc1);
2075 if (alloc2 != NULL)
2076 free (alloc2);
2077 return NULL;
2080 /* Compute the size of, and allocate space for, REL_HDR which is the
2081 section header for a section containing relocations for O. */
2083 bfd_boolean
2084 _bfd_elf_link_size_reloc_section (bfd *abfd,
2085 Elf_Internal_Shdr *rel_hdr,
2086 asection *o)
2088 bfd_size_type reloc_count;
2089 bfd_size_type num_rel_hashes;
2091 /* Figure out how many relocations there will be. */
2092 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2093 reloc_count = elf_section_data (o)->rel_count;
2094 else
2095 reloc_count = elf_section_data (o)->rel_count2;
2097 num_rel_hashes = o->reloc_count;
2098 if (num_rel_hashes < reloc_count)
2099 num_rel_hashes = reloc_count;
2101 /* That allows us to calculate the size of the section. */
2102 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2104 /* The contents field must last into write_object_contents, so we
2105 allocate it with bfd_alloc rather than malloc. Also since we
2106 cannot be sure that the contents will actually be filled in,
2107 we zero the allocated space. */
2108 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2109 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2110 return FALSE;
2112 /* We only allocate one set of hash entries, so we only do it the
2113 first time we are called. */
2114 if (elf_section_data (o)->rel_hashes == NULL
2115 && num_rel_hashes)
2117 struct elf_link_hash_entry **p;
2119 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2120 if (p == NULL)
2121 return FALSE;
2123 elf_section_data (o)->rel_hashes = p;
2126 return TRUE;
2129 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2130 originated from the section given by INPUT_REL_HDR) to the
2131 OUTPUT_BFD. */
2133 bfd_boolean
2134 _bfd_elf_link_output_relocs (bfd *output_bfd,
2135 asection *input_section,
2136 Elf_Internal_Shdr *input_rel_hdr,
2137 Elf_Internal_Rela *internal_relocs)
2139 Elf_Internal_Rela *irela;
2140 Elf_Internal_Rela *irelaend;
2141 bfd_byte *erel;
2142 Elf_Internal_Shdr *output_rel_hdr;
2143 asection *output_section;
2144 unsigned int *rel_countp = NULL;
2145 const struct elf_backend_data *bed;
2146 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2148 output_section = input_section->output_section;
2149 output_rel_hdr = NULL;
2151 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2152 == input_rel_hdr->sh_entsize)
2154 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2155 rel_countp = &elf_section_data (output_section)->rel_count;
2157 else if (elf_section_data (output_section)->rel_hdr2
2158 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2159 == input_rel_hdr->sh_entsize))
2161 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2162 rel_countp = &elf_section_data (output_section)->rel_count2;
2164 else
2166 (*_bfd_error_handler)
2167 (_("%B: relocation size mismatch in %B section %A"),
2168 output_bfd, input_section->owner, input_section);
2169 bfd_set_error (bfd_error_wrong_object_format);
2170 return FALSE;
2173 bed = get_elf_backend_data (output_bfd);
2174 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2175 swap_out = bed->s->swap_reloc_out;
2176 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2177 swap_out = bed->s->swap_reloca_out;
2178 else
2179 abort ();
2181 erel = output_rel_hdr->contents;
2182 erel += *rel_countp * input_rel_hdr->sh_entsize;
2183 irela = internal_relocs;
2184 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2185 * bed->s->int_rels_per_ext_rel);
2186 while (irela < irelaend)
2188 (*swap_out) (output_bfd, irela, erel);
2189 irela += bed->s->int_rels_per_ext_rel;
2190 erel += input_rel_hdr->sh_entsize;
2193 /* Bump the counter, so that we know where to add the next set of
2194 relocations. */
2195 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2197 return TRUE;
2200 /* Fix up the flags for a symbol. This handles various cases which
2201 can only be fixed after all the input files are seen. This is
2202 currently called by both adjust_dynamic_symbol and
2203 assign_sym_version, which is unnecessary but perhaps more robust in
2204 the face of future changes. */
2206 bfd_boolean
2207 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2208 struct elf_info_failed *eif)
2210 /* If this symbol was mentioned in a non-ELF file, try to set
2211 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2212 permit a non-ELF file to correctly refer to a symbol defined in
2213 an ELF dynamic object. */
2214 if (h->non_elf)
2216 while (h->root.type == bfd_link_hash_indirect)
2217 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2219 if (h->root.type != bfd_link_hash_defined
2220 && h->root.type != bfd_link_hash_defweak)
2222 h->ref_regular = 1;
2223 h->ref_regular_nonweak = 1;
2225 else
2227 if (h->root.u.def.section->owner != NULL
2228 && (bfd_get_flavour (h->root.u.def.section->owner)
2229 == bfd_target_elf_flavour))
2231 h->ref_regular = 1;
2232 h->ref_regular_nonweak = 1;
2234 else
2235 h->def_regular = 1;
2238 if (h->dynindx == -1
2239 && (h->def_dynamic
2240 || h->ref_dynamic))
2242 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2244 eif->failed = TRUE;
2245 return FALSE;
2249 else
2251 /* Unfortunately, NON_ELF is only correct if the symbol
2252 was first seen in a non-ELF file. Fortunately, if the symbol
2253 was first seen in an ELF file, we're probably OK unless the
2254 symbol was defined in a non-ELF file. Catch that case here.
2255 FIXME: We're still in trouble if the symbol was first seen in
2256 a dynamic object, and then later in a non-ELF regular object. */
2257 if ((h->root.type == bfd_link_hash_defined
2258 || h->root.type == bfd_link_hash_defweak)
2259 && !h->def_regular
2260 && (h->root.u.def.section->owner != NULL
2261 ? (bfd_get_flavour (h->root.u.def.section->owner)
2262 != bfd_target_elf_flavour)
2263 : (bfd_is_abs_section (h->root.u.def.section)
2264 && !h->def_dynamic)))
2265 h->def_regular = 1;
2268 /* If this is a final link, and the symbol was defined as a common
2269 symbol in a regular object file, and there was no definition in
2270 any dynamic object, then the linker will have allocated space for
2271 the symbol in a common section but the DEF_REGULAR
2272 flag will not have been set. */
2273 if (h->root.type == bfd_link_hash_defined
2274 && !h->def_regular
2275 && h->ref_regular
2276 && !h->def_dynamic
2277 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2278 h->def_regular = 1;
2280 /* If -Bsymbolic was used (which means to bind references to global
2281 symbols to the definition within the shared object), and this
2282 symbol was defined in a regular object, then it actually doesn't
2283 need a PLT entry. Likewise, if the symbol has non-default
2284 visibility. If the symbol has hidden or internal visibility, we
2285 will force it local. */
2286 if (h->needs_plt
2287 && eif->info->shared
2288 && is_elf_hash_table (eif->info->hash)
2289 && (eif->info->symbolic
2290 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2291 && h->def_regular)
2293 const struct elf_backend_data *bed;
2294 bfd_boolean force_local;
2296 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2298 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2299 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2300 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2303 /* If a weak undefined symbol has non-default visibility, we also
2304 hide it from the dynamic linker. */
2305 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2306 && h->root.type == bfd_link_hash_undefweak)
2308 const struct elf_backend_data *bed;
2309 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2310 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2313 /* If this is a weak defined symbol in a dynamic object, and we know
2314 the real definition in the dynamic object, copy interesting flags
2315 over to the real definition. */
2316 if (h->u.weakdef != NULL)
2318 struct elf_link_hash_entry *weakdef;
2320 weakdef = h->u.weakdef;
2321 if (h->root.type == bfd_link_hash_indirect)
2322 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2324 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2325 || h->root.type == bfd_link_hash_defweak);
2326 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2327 || weakdef->root.type == bfd_link_hash_defweak);
2328 BFD_ASSERT (weakdef->def_dynamic);
2330 /* If the real definition is defined by a regular object file,
2331 don't do anything special. See the longer description in
2332 _bfd_elf_adjust_dynamic_symbol, below. */
2333 if (weakdef->def_regular)
2334 h->u.weakdef = NULL;
2335 else
2337 const struct elf_backend_data *bed;
2339 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2340 (*bed->elf_backend_copy_indirect_symbol) (bed, weakdef, h);
2344 return TRUE;
2347 /* Make the backend pick a good value for a dynamic symbol. This is
2348 called via elf_link_hash_traverse, and also calls itself
2349 recursively. */
2351 bfd_boolean
2352 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2354 struct elf_info_failed *eif = data;
2355 bfd *dynobj;
2356 const struct elf_backend_data *bed;
2358 if (! is_elf_hash_table (eif->info->hash))
2359 return FALSE;
2361 if (h->root.type == bfd_link_hash_warning)
2363 h->plt = elf_hash_table (eif->info)->init_offset;
2364 h->got = elf_hash_table (eif->info)->init_offset;
2366 /* When warning symbols are created, they **replace** the "real"
2367 entry in the hash table, thus we never get to see the real
2368 symbol in a hash traversal. So look at it now. */
2369 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2372 /* Ignore indirect symbols. These are added by the versioning code. */
2373 if (h->root.type == bfd_link_hash_indirect)
2374 return TRUE;
2376 /* Fix the symbol flags. */
2377 if (! _bfd_elf_fix_symbol_flags (h, eif))
2378 return FALSE;
2380 /* If this symbol does not require a PLT entry, and it is not
2381 defined by a dynamic object, or is not referenced by a regular
2382 object, ignore it. We do have to handle a weak defined symbol,
2383 even if no regular object refers to it, if we decided to add it
2384 to the dynamic symbol table. FIXME: Do we normally need to worry
2385 about symbols which are defined by one dynamic object and
2386 referenced by another one? */
2387 if (!h->needs_plt
2388 && (h->def_regular
2389 || !h->def_dynamic
2390 || (!h->ref_regular
2391 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2393 h->plt = elf_hash_table (eif->info)->init_offset;
2394 return TRUE;
2397 /* If we've already adjusted this symbol, don't do it again. This
2398 can happen via a recursive call. */
2399 if (h->dynamic_adjusted)
2400 return TRUE;
2402 /* Don't look at this symbol again. Note that we must set this
2403 after checking the above conditions, because we may look at a
2404 symbol once, decide not to do anything, and then get called
2405 recursively later after REF_REGULAR is set below. */
2406 h->dynamic_adjusted = 1;
2408 /* If this is a weak definition, and we know a real definition, and
2409 the real symbol is not itself defined by a regular object file,
2410 then get a good value for the real definition. We handle the
2411 real symbol first, for the convenience of the backend routine.
2413 Note that there is a confusing case here. If the real definition
2414 is defined by a regular object file, we don't get the real symbol
2415 from the dynamic object, but we do get the weak symbol. If the
2416 processor backend uses a COPY reloc, then if some routine in the
2417 dynamic object changes the real symbol, we will not see that
2418 change in the corresponding weak symbol. This is the way other
2419 ELF linkers work as well, and seems to be a result of the shared
2420 library model.
2422 I will clarify this issue. Most SVR4 shared libraries define the
2423 variable _timezone and define timezone as a weak synonym. The
2424 tzset call changes _timezone. If you write
2425 extern int timezone;
2426 int _timezone = 5;
2427 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2428 you might expect that, since timezone is a synonym for _timezone,
2429 the same number will print both times. However, if the processor
2430 backend uses a COPY reloc, then actually timezone will be copied
2431 into your process image, and, since you define _timezone
2432 yourself, _timezone will not. Thus timezone and _timezone will
2433 wind up at different memory locations. The tzset call will set
2434 _timezone, leaving timezone unchanged. */
2436 if (h->u.weakdef != NULL)
2438 /* If we get to this point, we know there is an implicit
2439 reference by a regular object file via the weak symbol H.
2440 FIXME: Is this really true? What if the traversal finds
2441 H->U.WEAKDEF before it finds H? */
2442 h->u.weakdef->ref_regular = 1;
2444 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2445 return FALSE;
2448 /* If a symbol has no type and no size and does not require a PLT
2449 entry, then we are probably about to do the wrong thing here: we
2450 are probably going to create a COPY reloc for an empty object.
2451 This case can arise when a shared object is built with assembly
2452 code, and the assembly code fails to set the symbol type. */
2453 if (h->size == 0
2454 && h->type == STT_NOTYPE
2455 && !h->needs_plt)
2456 (*_bfd_error_handler)
2457 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2458 h->root.root.string);
2460 dynobj = elf_hash_table (eif->info)->dynobj;
2461 bed = get_elf_backend_data (dynobj);
2462 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2464 eif->failed = TRUE;
2465 return FALSE;
2468 return TRUE;
2471 /* Adjust all external symbols pointing into SEC_MERGE sections
2472 to reflect the object merging within the sections. */
2474 bfd_boolean
2475 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2477 asection *sec;
2479 if (h->root.type == bfd_link_hash_warning)
2480 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2482 if ((h->root.type == bfd_link_hash_defined
2483 || h->root.type == bfd_link_hash_defweak)
2484 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2485 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2487 bfd *output_bfd = data;
2489 h->root.u.def.value =
2490 _bfd_merged_section_offset (output_bfd,
2491 &h->root.u.def.section,
2492 elf_section_data (sec)->sec_info,
2493 h->root.u.def.value);
2496 return TRUE;
2499 /* Returns false if the symbol referred to by H should be considered
2500 to resolve local to the current module, and true if it should be
2501 considered to bind dynamically. */
2503 bfd_boolean
2504 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2505 struct bfd_link_info *info,
2506 bfd_boolean ignore_protected)
2508 bfd_boolean binding_stays_local_p;
2510 if (h == NULL)
2511 return FALSE;
2513 while (h->root.type == bfd_link_hash_indirect
2514 || h->root.type == bfd_link_hash_warning)
2515 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2517 /* If it was forced local, then clearly it's not dynamic. */
2518 if (h->dynindx == -1)
2519 return FALSE;
2520 if (h->forced_local)
2521 return FALSE;
2523 /* Identify the cases where name binding rules say that a
2524 visible symbol resolves locally. */
2525 binding_stays_local_p = info->executable || info->symbolic;
2527 switch (ELF_ST_VISIBILITY (h->other))
2529 case STV_INTERNAL:
2530 case STV_HIDDEN:
2531 return FALSE;
2533 case STV_PROTECTED:
2534 /* Proper resolution for function pointer equality may require
2535 that these symbols perhaps be resolved dynamically, even though
2536 we should be resolving them to the current module. */
2537 if (!ignore_protected || h->type != STT_FUNC)
2538 binding_stays_local_p = TRUE;
2539 break;
2541 default:
2542 break;
2545 /* If it isn't defined locally, then clearly it's dynamic. */
2546 if (!h->def_regular)
2547 return TRUE;
2549 /* Otherwise, the symbol is dynamic if binding rules don't tell
2550 us that it remains local. */
2551 return !binding_stays_local_p;
2554 /* Return true if the symbol referred to by H should be considered
2555 to resolve local to the current module, and false otherwise. Differs
2556 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2557 undefined symbols and weak symbols. */
2559 bfd_boolean
2560 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2561 struct bfd_link_info *info,
2562 bfd_boolean local_protected)
2564 /* If it's a local sym, of course we resolve locally. */
2565 if (h == NULL)
2566 return TRUE;
2568 /* Common symbols that become definitions don't get the DEF_REGULAR
2569 flag set, so test it first, and don't bail out. */
2570 if (ELF_COMMON_DEF_P (h))
2571 /* Do nothing. */;
2572 /* If we don't have a definition in a regular file, then we can't
2573 resolve locally. The sym is either undefined or dynamic. */
2574 else if (!h->def_regular)
2575 return FALSE;
2577 /* Forced local symbols resolve locally. */
2578 if (h->forced_local)
2579 return TRUE;
2581 /* As do non-dynamic symbols. */
2582 if (h->dynindx == -1)
2583 return TRUE;
2585 /* At this point, we know the symbol is defined and dynamic. In an
2586 executable it must resolve locally, likewise when building symbolic
2587 shared libraries. */
2588 if (info->executable || info->symbolic)
2589 return TRUE;
2591 /* Now deal with defined dynamic symbols in shared libraries. Ones
2592 with default visibility might not resolve locally. */
2593 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2594 return FALSE;
2596 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2597 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2598 return TRUE;
2600 /* STV_PROTECTED non-function symbols are local. */
2601 if (h->type != STT_FUNC)
2602 return TRUE;
2604 /* Function pointer equality tests may require that STV_PROTECTED
2605 symbols be treated as dynamic symbols, even when we know that the
2606 dynamic linker will resolve them locally. */
2607 return local_protected;
2610 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2611 aligned. Returns the first TLS output section. */
2613 struct bfd_section *
2614 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2616 struct bfd_section *sec, *tls;
2617 unsigned int align = 0;
2619 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2620 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2621 break;
2622 tls = sec;
2624 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2625 if (sec->alignment_power > align)
2626 align = sec->alignment_power;
2628 elf_hash_table (info)->tls_sec = tls;
2630 /* Ensure the alignment of the first section is the largest alignment,
2631 so that the tls segment starts aligned. */
2632 if (tls != NULL)
2633 tls->alignment_power = align;
2635 return tls;
2638 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2639 static bfd_boolean
2640 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2641 Elf_Internal_Sym *sym)
2643 /* Local symbols do not count, but target specific ones might. */
2644 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2645 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2646 return FALSE;
2648 /* Function symbols do not count. */
2649 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2650 return FALSE;
2652 /* If the section is undefined, then so is the symbol. */
2653 if (sym->st_shndx == SHN_UNDEF)
2654 return FALSE;
2656 /* If the symbol is defined in the common section, then
2657 it is a common definition and so does not count. */
2658 if (sym->st_shndx == SHN_COMMON)
2659 return FALSE;
2661 /* If the symbol is in a target specific section then we
2662 must rely upon the backend to tell us what it is. */
2663 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2664 /* FIXME - this function is not coded yet:
2666 return _bfd_is_global_symbol_definition (abfd, sym);
2668 Instead for now assume that the definition is not global,
2669 Even if this is wrong, at least the linker will behave
2670 in the same way that it used to do. */
2671 return FALSE;
2673 return TRUE;
2676 /* Search the symbol table of the archive element of the archive ABFD
2677 whose archive map contains a mention of SYMDEF, and determine if
2678 the symbol is defined in this element. */
2679 static bfd_boolean
2680 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2682 Elf_Internal_Shdr * hdr;
2683 bfd_size_type symcount;
2684 bfd_size_type extsymcount;
2685 bfd_size_type extsymoff;
2686 Elf_Internal_Sym *isymbuf;
2687 Elf_Internal_Sym *isym;
2688 Elf_Internal_Sym *isymend;
2689 bfd_boolean result;
2691 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2692 if (abfd == NULL)
2693 return FALSE;
2695 if (! bfd_check_format (abfd, bfd_object))
2696 return FALSE;
2698 /* If we have already included the element containing this symbol in the
2699 link then we do not need to include it again. Just claim that any symbol
2700 it contains is not a definition, so that our caller will not decide to
2701 (re)include this element. */
2702 if (abfd->archive_pass)
2703 return FALSE;
2705 /* Select the appropriate symbol table. */
2706 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2707 hdr = &elf_tdata (abfd)->symtab_hdr;
2708 else
2709 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2711 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2713 /* The sh_info field of the symtab header tells us where the
2714 external symbols start. We don't care about the local symbols. */
2715 if (elf_bad_symtab (abfd))
2717 extsymcount = symcount;
2718 extsymoff = 0;
2720 else
2722 extsymcount = symcount - hdr->sh_info;
2723 extsymoff = hdr->sh_info;
2726 if (extsymcount == 0)
2727 return FALSE;
2729 /* Read in the symbol table. */
2730 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2731 NULL, NULL, NULL);
2732 if (isymbuf == NULL)
2733 return FALSE;
2735 /* Scan the symbol table looking for SYMDEF. */
2736 result = FALSE;
2737 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2739 const char *name;
2741 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2742 isym->st_name);
2743 if (name == NULL)
2744 break;
2746 if (strcmp (name, symdef->name) == 0)
2748 result = is_global_data_symbol_definition (abfd, isym);
2749 break;
2753 free (isymbuf);
2755 return result;
2758 /* Add an entry to the .dynamic table. */
2760 bfd_boolean
2761 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2762 bfd_vma tag,
2763 bfd_vma val)
2765 struct elf_link_hash_table *hash_table;
2766 const struct elf_backend_data *bed;
2767 asection *s;
2768 bfd_size_type newsize;
2769 bfd_byte *newcontents;
2770 Elf_Internal_Dyn dyn;
2772 hash_table = elf_hash_table (info);
2773 if (! is_elf_hash_table (hash_table))
2774 return FALSE;
2776 if (info->warn_shared_textrel && info->shared && tag == DT_TEXTREL)
2777 _bfd_error_handler
2778 (_("warning: creating a DT_TEXTREL in a shared object."));
2780 bed = get_elf_backend_data (hash_table->dynobj);
2781 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2782 BFD_ASSERT (s != NULL);
2784 newsize = s->size + bed->s->sizeof_dyn;
2785 newcontents = bfd_realloc (s->contents, newsize);
2786 if (newcontents == NULL)
2787 return FALSE;
2789 dyn.d_tag = tag;
2790 dyn.d_un.d_val = val;
2791 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2793 s->size = newsize;
2794 s->contents = newcontents;
2796 return TRUE;
2799 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2800 otherwise just check whether one already exists. Returns -1 on error,
2801 1 if a DT_NEEDED tag already exists, and 0 on success. */
2803 static int
2804 elf_add_dt_needed_tag (bfd *abfd,
2805 struct bfd_link_info *info,
2806 const char *soname,
2807 bfd_boolean do_it)
2809 struct elf_link_hash_table *hash_table;
2810 bfd_size_type oldsize;
2811 bfd_size_type strindex;
2813 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2814 return -1;
2816 hash_table = elf_hash_table (info);
2817 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2818 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2819 if (strindex == (bfd_size_type) -1)
2820 return -1;
2822 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2824 asection *sdyn;
2825 const struct elf_backend_data *bed;
2826 bfd_byte *extdyn;
2828 bed = get_elf_backend_data (hash_table->dynobj);
2829 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2830 if (sdyn != NULL)
2831 for (extdyn = sdyn->contents;
2832 extdyn < sdyn->contents + sdyn->size;
2833 extdyn += bed->s->sizeof_dyn)
2835 Elf_Internal_Dyn dyn;
2837 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2838 if (dyn.d_tag == DT_NEEDED
2839 && dyn.d_un.d_val == strindex)
2841 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2842 return 1;
2847 if (do_it)
2849 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2850 return -1;
2852 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2853 return -1;
2855 else
2856 /* We were just checking for existence of the tag. */
2857 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2859 return 0;
2862 /* Called via elf_link_hash_traverse, elf_smash_syms sets all symbols
2863 belonging to NOT_NEEDED to bfd_link_hash_new. We know there are no
2864 references from regular objects to these symbols.
2866 ??? Should we do something about references from other dynamic
2867 obects? If not, we potentially lose some warnings about undefined
2868 symbols. But how can we recover the initial undefined / undefweak
2869 state? */
2871 struct elf_smash_syms_data
2873 bfd *not_needed;
2874 struct elf_link_hash_table *htab;
2875 bfd_boolean twiddled;
2878 static bfd_boolean
2879 elf_smash_syms (struct elf_link_hash_entry *h, void *data)
2881 struct elf_smash_syms_data *inf = (struct elf_smash_syms_data *) data;
2882 struct bfd_link_hash_entry *bh;
2884 switch (h->root.type)
2886 default:
2887 case bfd_link_hash_new:
2888 return TRUE;
2890 case bfd_link_hash_undefined:
2891 if (h->root.u.undef.abfd != inf->not_needed)
2892 return TRUE;
2893 if (h->root.u.undef.weak != NULL
2894 && h->root.u.undef.weak != inf->not_needed)
2896 /* Symbol was undefweak in u.undef.weak bfd, and has become
2897 undefined in as-needed lib. Restore weak. */
2898 h->root.type = bfd_link_hash_undefweak;
2899 h->root.u.undef.abfd = h->root.u.undef.weak;
2900 if (h->root.u.undef.next != NULL
2901 || inf->htab->root.undefs_tail == &h->root)
2902 inf->twiddled = TRUE;
2903 return TRUE;
2905 break;
2907 case bfd_link_hash_undefweak:
2908 if (h->root.u.undef.abfd != inf->not_needed)
2909 return TRUE;
2910 break;
2912 case bfd_link_hash_defined:
2913 case bfd_link_hash_defweak:
2914 if (h->root.u.def.section->owner != inf->not_needed)
2915 return TRUE;
2916 break;
2918 case bfd_link_hash_common:
2919 if (h->root.u.c.p->section->owner != inf->not_needed)
2920 return TRUE;
2921 break;
2923 case bfd_link_hash_warning:
2924 case bfd_link_hash_indirect:
2925 elf_smash_syms ((struct elf_link_hash_entry *) h->root.u.i.link, data);
2926 if (h->root.u.i.link->type != bfd_link_hash_new)
2927 return TRUE;
2928 if (h->root.u.i.link->u.undef.abfd != inf->not_needed)
2929 return TRUE;
2930 break;
2933 /* There is no way we can undo symbol table state from defined or
2934 defweak back to undefined. */
2935 if (h->ref_regular)
2936 abort ();
2938 /* Set sym back to newly created state, but keep undef.next if it is
2939 being used as a list pointer. */
2940 bh = h->root.u.undef.next;
2941 if (bh == &h->root)
2942 bh = NULL;
2943 if (bh != NULL || inf->htab->root.undefs_tail == &h->root)
2944 inf->twiddled = TRUE;
2945 (*inf->htab->root.table.newfunc) (&h->root.root,
2946 &inf->htab->root.table,
2947 h->root.root.string);
2948 h->root.u.undef.next = bh;
2949 h->root.u.undef.abfd = inf->not_needed;
2950 h->non_elf = 0;
2951 return TRUE;
2954 /* Sort symbol by value and section. */
2955 static int
2956 elf_sort_symbol (const void *arg1, const void *arg2)
2958 const struct elf_link_hash_entry *h1;
2959 const struct elf_link_hash_entry *h2;
2960 bfd_signed_vma vdiff;
2962 h1 = *(const struct elf_link_hash_entry **) arg1;
2963 h2 = *(const struct elf_link_hash_entry **) arg2;
2964 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2965 if (vdiff != 0)
2966 return vdiff > 0 ? 1 : -1;
2967 else
2969 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2970 if (sdiff != 0)
2971 return sdiff > 0 ? 1 : -1;
2973 return 0;
2976 /* This function is used to adjust offsets into .dynstr for
2977 dynamic symbols. This is called via elf_link_hash_traverse. */
2979 static bfd_boolean
2980 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
2982 struct elf_strtab_hash *dynstr = data;
2984 if (h->root.type == bfd_link_hash_warning)
2985 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2987 if (h->dynindx != -1)
2988 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
2989 return TRUE;
2992 /* Assign string offsets in .dynstr, update all structures referencing
2993 them. */
2995 static bfd_boolean
2996 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
2998 struct elf_link_hash_table *hash_table = elf_hash_table (info);
2999 struct elf_link_local_dynamic_entry *entry;
3000 struct elf_strtab_hash *dynstr = hash_table->dynstr;
3001 bfd *dynobj = hash_table->dynobj;
3002 asection *sdyn;
3003 bfd_size_type size;
3004 const struct elf_backend_data *bed;
3005 bfd_byte *extdyn;
3007 _bfd_elf_strtab_finalize (dynstr);
3008 size = _bfd_elf_strtab_size (dynstr);
3010 bed = get_elf_backend_data (dynobj);
3011 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3012 BFD_ASSERT (sdyn != NULL);
3014 /* Update all .dynamic entries referencing .dynstr strings. */
3015 for (extdyn = sdyn->contents;
3016 extdyn < sdyn->contents + sdyn->size;
3017 extdyn += bed->s->sizeof_dyn)
3019 Elf_Internal_Dyn dyn;
3021 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3022 switch (dyn.d_tag)
3024 case DT_STRSZ:
3025 dyn.d_un.d_val = size;
3026 break;
3027 case DT_NEEDED:
3028 case DT_SONAME:
3029 case DT_RPATH:
3030 case DT_RUNPATH:
3031 case DT_FILTER:
3032 case DT_AUXILIARY:
3033 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3034 break;
3035 default:
3036 continue;
3038 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3041 /* Now update local dynamic symbols. */
3042 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3043 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3044 entry->isym.st_name);
3046 /* And the rest of dynamic symbols. */
3047 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3049 /* Adjust version definitions. */
3050 if (elf_tdata (output_bfd)->cverdefs)
3052 asection *s;
3053 bfd_byte *p;
3054 bfd_size_type i;
3055 Elf_Internal_Verdef def;
3056 Elf_Internal_Verdaux defaux;
3058 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3059 p = s->contents;
3062 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3063 &def);
3064 p += sizeof (Elf_External_Verdef);
3065 if (def.vd_aux != sizeof (Elf_External_Verdef))
3066 continue;
3067 for (i = 0; i < def.vd_cnt; ++i)
3069 _bfd_elf_swap_verdaux_in (output_bfd,
3070 (Elf_External_Verdaux *) p, &defaux);
3071 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3072 defaux.vda_name);
3073 _bfd_elf_swap_verdaux_out (output_bfd,
3074 &defaux, (Elf_External_Verdaux *) p);
3075 p += sizeof (Elf_External_Verdaux);
3078 while (def.vd_next);
3081 /* Adjust version references. */
3082 if (elf_tdata (output_bfd)->verref)
3084 asection *s;
3085 bfd_byte *p;
3086 bfd_size_type i;
3087 Elf_Internal_Verneed need;
3088 Elf_Internal_Vernaux needaux;
3090 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3091 p = s->contents;
3094 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3095 &need);
3096 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3097 _bfd_elf_swap_verneed_out (output_bfd, &need,
3098 (Elf_External_Verneed *) p);
3099 p += sizeof (Elf_External_Verneed);
3100 for (i = 0; i < need.vn_cnt; ++i)
3102 _bfd_elf_swap_vernaux_in (output_bfd,
3103 (Elf_External_Vernaux *) p, &needaux);
3104 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3105 needaux.vna_name);
3106 _bfd_elf_swap_vernaux_out (output_bfd,
3107 &needaux,
3108 (Elf_External_Vernaux *) p);
3109 p += sizeof (Elf_External_Vernaux);
3112 while (need.vn_next);
3115 return TRUE;
3118 /* Add symbols from an ELF object file to the linker hash table. */
3120 static bfd_boolean
3121 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3123 bfd_boolean (*add_symbol_hook)
3124 (bfd *, struct bfd_link_info *, Elf_Internal_Sym *,
3125 const char **, flagword *, asection **, bfd_vma *);
3126 bfd_boolean (*check_relocs)
3127 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
3128 bfd_boolean (*check_directives)
3129 (bfd *, struct bfd_link_info *);
3130 bfd_boolean collect;
3131 Elf_Internal_Shdr *hdr;
3132 bfd_size_type symcount;
3133 bfd_size_type extsymcount;
3134 bfd_size_type extsymoff;
3135 struct elf_link_hash_entry **sym_hash;
3136 bfd_boolean dynamic;
3137 Elf_External_Versym *extversym = NULL;
3138 Elf_External_Versym *ever;
3139 struct elf_link_hash_entry *weaks;
3140 struct elf_link_hash_entry **nondeflt_vers = NULL;
3141 bfd_size_type nondeflt_vers_cnt = 0;
3142 Elf_Internal_Sym *isymbuf = NULL;
3143 Elf_Internal_Sym *isym;
3144 Elf_Internal_Sym *isymend;
3145 const struct elf_backend_data *bed;
3146 bfd_boolean add_needed;
3147 struct elf_link_hash_table * hash_table;
3148 bfd_size_type amt;
3150 hash_table = elf_hash_table (info);
3152 bed = get_elf_backend_data (abfd);
3153 add_symbol_hook = bed->elf_add_symbol_hook;
3154 collect = bed->collect;
3156 if ((abfd->flags & DYNAMIC) == 0)
3157 dynamic = FALSE;
3158 else
3160 dynamic = TRUE;
3162 /* You can't use -r against a dynamic object. Also, there's no
3163 hope of using a dynamic object which does not exactly match
3164 the format of the output file. */
3165 if (info->relocatable
3166 || !is_elf_hash_table (hash_table)
3167 || hash_table->root.creator != abfd->xvec)
3169 if (info->relocatable)
3170 bfd_set_error (bfd_error_invalid_operation);
3171 else
3172 bfd_set_error (bfd_error_wrong_format);
3173 goto error_return;
3177 /* As a GNU extension, any input sections which are named
3178 .gnu.warning.SYMBOL are treated as warning symbols for the given
3179 symbol. This differs from .gnu.warning sections, which generate
3180 warnings when they are included in an output file. */
3181 if (info->executable)
3183 asection *s;
3185 for (s = abfd->sections; s != NULL; s = s->next)
3187 const char *name;
3189 name = bfd_get_section_name (abfd, s);
3190 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
3192 char *msg;
3193 bfd_size_type sz;
3195 name += sizeof ".gnu.warning." - 1;
3197 /* If this is a shared object, then look up the symbol
3198 in the hash table. If it is there, and it is already
3199 been defined, then we will not be using the entry
3200 from this shared object, so we don't need to warn.
3201 FIXME: If we see the definition in a regular object
3202 later on, we will warn, but we shouldn't. The only
3203 fix is to keep track of what warnings we are supposed
3204 to emit, and then handle them all at the end of the
3205 link. */
3206 if (dynamic)
3208 struct elf_link_hash_entry *h;
3210 h = elf_link_hash_lookup (hash_table, name,
3211 FALSE, FALSE, TRUE);
3213 /* FIXME: What about bfd_link_hash_common? */
3214 if (h != NULL
3215 && (h->root.type == bfd_link_hash_defined
3216 || h->root.type == bfd_link_hash_defweak))
3218 /* We don't want to issue this warning. Clobber
3219 the section size so that the warning does not
3220 get copied into the output file. */
3221 s->size = 0;
3222 continue;
3226 sz = s->size;
3227 msg = bfd_alloc (abfd, sz + 1);
3228 if (msg == NULL)
3229 goto error_return;
3231 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3232 goto error_return;
3234 msg[sz] = '\0';
3236 if (! (_bfd_generic_link_add_one_symbol
3237 (info, abfd, name, BSF_WARNING, s, 0, msg,
3238 FALSE, collect, NULL)))
3239 goto error_return;
3241 if (! info->relocatable)
3243 /* Clobber the section size so that the warning does
3244 not get copied into the output file. */
3245 s->size = 0;
3247 /* Also set SEC_EXCLUDE, so that symbols defined in
3248 the warning section don't get copied to the output. */
3249 s->flags |= SEC_EXCLUDE;
3255 add_needed = TRUE;
3256 if (! dynamic)
3258 /* If we are creating a shared library, create all the dynamic
3259 sections immediately. We need to attach them to something,
3260 so we attach them to this BFD, provided it is the right
3261 format. FIXME: If there are no input BFD's of the same
3262 format as the output, we can't make a shared library. */
3263 if (info->shared
3264 && is_elf_hash_table (hash_table)
3265 && hash_table->root.creator == abfd->xvec
3266 && ! hash_table->dynamic_sections_created)
3268 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3269 goto error_return;
3272 else if (!is_elf_hash_table (hash_table))
3273 goto error_return;
3274 else
3276 asection *s;
3277 const char *soname = NULL;
3278 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3279 int ret;
3281 /* ld --just-symbols and dynamic objects don't mix very well.
3282 Test for --just-symbols by looking at info set up by
3283 _bfd_elf_link_just_syms. */
3284 if ((s = abfd->sections) != NULL
3285 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3286 goto error_return;
3288 /* If this dynamic lib was specified on the command line with
3289 --as-needed in effect, then we don't want to add a DT_NEEDED
3290 tag unless the lib is actually used. Similary for libs brought
3291 in by another lib's DT_NEEDED. When --no-add-needed is used
3292 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3293 any dynamic library in DT_NEEDED tags in the dynamic lib at
3294 all. */
3295 add_needed = (elf_dyn_lib_class (abfd)
3296 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3297 | DYN_NO_NEEDED)) == 0;
3299 s = bfd_get_section_by_name (abfd, ".dynamic");
3300 if (s != NULL)
3302 bfd_byte *dynbuf;
3303 bfd_byte *extdyn;
3304 int elfsec;
3305 unsigned long shlink;
3307 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3308 goto error_free_dyn;
3310 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3311 if (elfsec == -1)
3312 goto error_free_dyn;
3313 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3315 for (extdyn = dynbuf;
3316 extdyn < dynbuf + s->size;
3317 extdyn += bed->s->sizeof_dyn)
3319 Elf_Internal_Dyn dyn;
3321 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3322 if (dyn.d_tag == DT_SONAME)
3324 unsigned int tagv = dyn.d_un.d_val;
3325 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3326 if (soname == NULL)
3327 goto error_free_dyn;
3329 if (dyn.d_tag == DT_NEEDED)
3331 struct bfd_link_needed_list *n, **pn;
3332 char *fnm, *anm;
3333 unsigned int tagv = dyn.d_un.d_val;
3335 amt = sizeof (struct bfd_link_needed_list);
3336 n = bfd_alloc (abfd, amt);
3337 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3338 if (n == NULL || fnm == NULL)
3339 goto error_free_dyn;
3340 amt = strlen (fnm) + 1;
3341 anm = bfd_alloc (abfd, amt);
3342 if (anm == NULL)
3343 goto error_free_dyn;
3344 memcpy (anm, fnm, amt);
3345 n->name = anm;
3346 n->by = abfd;
3347 n->next = NULL;
3348 for (pn = & hash_table->needed;
3349 *pn != NULL;
3350 pn = &(*pn)->next)
3352 *pn = n;
3354 if (dyn.d_tag == DT_RUNPATH)
3356 struct bfd_link_needed_list *n, **pn;
3357 char *fnm, *anm;
3358 unsigned int tagv = dyn.d_un.d_val;
3360 amt = sizeof (struct bfd_link_needed_list);
3361 n = bfd_alloc (abfd, amt);
3362 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3363 if (n == NULL || fnm == NULL)
3364 goto error_free_dyn;
3365 amt = strlen (fnm) + 1;
3366 anm = bfd_alloc (abfd, amt);
3367 if (anm == NULL)
3368 goto error_free_dyn;
3369 memcpy (anm, fnm, amt);
3370 n->name = anm;
3371 n->by = abfd;
3372 n->next = NULL;
3373 for (pn = & runpath;
3374 *pn != NULL;
3375 pn = &(*pn)->next)
3377 *pn = n;
3379 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3380 if (!runpath && dyn.d_tag == DT_RPATH)
3382 struct bfd_link_needed_list *n, **pn;
3383 char *fnm, *anm;
3384 unsigned int tagv = dyn.d_un.d_val;
3386 amt = sizeof (struct bfd_link_needed_list);
3387 n = bfd_alloc (abfd, amt);
3388 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3389 if (n == NULL || fnm == NULL)
3390 goto error_free_dyn;
3391 amt = strlen (fnm) + 1;
3392 anm = bfd_alloc (abfd, amt);
3393 if (anm == NULL)
3395 error_free_dyn:
3396 free (dynbuf);
3397 goto error_return;
3399 memcpy (anm, fnm, amt);
3400 n->name = anm;
3401 n->by = abfd;
3402 n->next = NULL;
3403 for (pn = & rpath;
3404 *pn != NULL;
3405 pn = &(*pn)->next)
3407 *pn = n;
3411 free (dynbuf);
3414 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3415 frees all more recently bfd_alloc'd blocks as well. */
3416 if (runpath)
3417 rpath = runpath;
3419 if (rpath)
3421 struct bfd_link_needed_list **pn;
3422 for (pn = & hash_table->runpath;
3423 *pn != NULL;
3424 pn = &(*pn)->next)
3426 *pn = rpath;
3429 /* We do not want to include any of the sections in a dynamic
3430 object in the output file. We hack by simply clobbering the
3431 list of sections in the BFD. This could be handled more
3432 cleanly by, say, a new section flag; the existing
3433 SEC_NEVER_LOAD flag is not the one we want, because that one
3434 still implies that the section takes up space in the output
3435 file. */
3436 bfd_section_list_clear (abfd);
3438 /* Find the name to use in a DT_NEEDED entry that refers to this
3439 object. If the object has a DT_SONAME entry, we use it.
3440 Otherwise, if the generic linker stuck something in
3441 elf_dt_name, we use that. Otherwise, we just use the file
3442 name. */
3443 if (soname == NULL || *soname == '\0')
3445 soname = elf_dt_name (abfd);
3446 if (soname == NULL || *soname == '\0')
3447 soname = bfd_get_filename (abfd);
3450 /* Save the SONAME because sometimes the linker emulation code
3451 will need to know it. */
3452 elf_dt_name (abfd) = soname;
3454 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3455 if (ret < 0)
3456 goto error_return;
3458 /* If we have already included this dynamic object in the
3459 link, just ignore it. There is no reason to include a
3460 particular dynamic object more than once. */
3461 if (ret > 0)
3462 return TRUE;
3465 /* If this is a dynamic object, we always link against the .dynsym
3466 symbol table, not the .symtab symbol table. The dynamic linker
3467 will only see the .dynsym symbol table, so there is no reason to
3468 look at .symtab for a dynamic object. */
3470 if (! dynamic || elf_dynsymtab (abfd) == 0)
3471 hdr = &elf_tdata (abfd)->symtab_hdr;
3472 else
3473 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3475 symcount = hdr->sh_size / bed->s->sizeof_sym;
3477 /* The sh_info field of the symtab header tells us where the
3478 external symbols start. We don't care about the local symbols at
3479 this point. */
3480 if (elf_bad_symtab (abfd))
3482 extsymcount = symcount;
3483 extsymoff = 0;
3485 else
3487 extsymcount = symcount - hdr->sh_info;
3488 extsymoff = hdr->sh_info;
3491 sym_hash = NULL;
3492 if (extsymcount != 0)
3494 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3495 NULL, NULL, NULL);
3496 if (isymbuf == NULL)
3497 goto error_return;
3499 /* We store a pointer to the hash table entry for each external
3500 symbol. */
3501 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3502 sym_hash = bfd_alloc (abfd, amt);
3503 if (sym_hash == NULL)
3504 goto error_free_sym;
3505 elf_sym_hashes (abfd) = sym_hash;
3508 if (dynamic)
3510 /* Read in any version definitions. */
3511 if (!_bfd_elf_slurp_version_tables (abfd,
3512 info->default_imported_symver))
3513 goto error_free_sym;
3515 /* Read in the symbol versions, but don't bother to convert them
3516 to internal format. */
3517 if (elf_dynversym (abfd) != 0)
3519 Elf_Internal_Shdr *versymhdr;
3521 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3522 extversym = bfd_malloc (versymhdr->sh_size);
3523 if (extversym == NULL)
3524 goto error_free_sym;
3525 amt = versymhdr->sh_size;
3526 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3527 || bfd_bread (extversym, amt, abfd) != amt)
3528 goto error_free_vers;
3532 weaks = NULL;
3534 ever = extversym != NULL ? extversym + extsymoff : NULL;
3535 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3536 isym < isymend;
3537 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3539 int bind;
3540 bfd_vma value;
3541 asection *sec, *new_sec;
3542 flagword flags;
3543 const char *name;
3544 struct elf_link_hash_entry *h;
3545 bfd_boolean definition;
3546 bfd_boolean size_change_ok;
3547 bfd_boolean type_change_ok;
3548 bfd_boolean new_weakdef;
3549 bfd_boolean override;
3550 unsigned int old_alignment;
3551 bfd *old_bfd;
3553 override = FALSE;
3555 flags = BSF_NO_FLAGS;
3556 sec = NULL;
3557 value = isym->st_value;
3558 *sym_hash = NULL;
3560 bind = ELF_ST_BIND (isym->st_info);
3561 if (bind == STB_LOCAL)
3563 /* This should be impossible, since ELF requires that all
3564 global symbols follow all local symbols, and that sh_info
3565 point to the first global symbol. Unfortunately, Irix 5
3566 screws this up. */
3567 continue;
3569 else if (bind == STB_GLOBAL)
3571 if (isym->st_shndx != SHN_UNDEF
3572 && isym->st_shndx != SHN_COMMON)
3573 flags = BSF_GLOBAL;
3575 else if (bind == STB_WEAK)
3576 flags = BSF_WEAK;
3577 else
3579 /* Leave it up to the processor backend. */
3582 if (isym->st_shndx == SHN_UNDEF)
3583 sec = bfd_und_section_ptr;
3584 else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
3586 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3587 if (sec == NULL)
3588 sec = bfd_abs_section_ptr;
3589 else if (sec->kept_section)
3591 /* Symbols from discarded section are undefined, and have
3592 default visibility. */
3593 sec = bfd_und_section_ptr;
3594 isym->st_shndx = SHN_UNDEF;
3595 isym->st_other = STV_DEFAULT
3596 | (isym->st_other & ~ ELF_ST_VISIBILITY(-1));
3598 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3599 value -= sec->vma;
3601 else if (isym->st_shndx == SHN_ABS)
3602 sec = bfd_abs_section_ptr;
3603 else if (isym->st_shndx == SHN_COMMON)
3605 sec = bfd_com_section_ptr;
3606 /* What ELF calls the size we call the value. What ELF
3607 calls the value we call the alignment. */
3608 value = isym->st_size;
3610 else
3612 /* Leave it up to the processor backend. */
3615 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3616 isym->st_name);
3617 if (name == NULL)
3618 goto error_free_vers;
3620 if (isym->st_shndx == SHN_COMMON
3621 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3623 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3625 if (tcomm == NULL)
3627 tcomm = bfd_make_section (abfd, ".tcommon");
3628 if (tcomm == NULL
3629 || !bfd_set_section_flags (abfd, tcomm, (SEC_ALLOC
3630 | SEC_IS_COMMON
3631 | SEC_LINKER_CREATED
3632 | SEC_THREAD_LOCAL)))
3633 goto error_free_vers;
3635 sec = tcomm;
3637 else if (add_symbol_hook)
3639 if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec,
3640 &value))
3641 goto error_free_vers;
3643 /* The hook function sets the name to NULL if this symbol
3644 should be skipped for some reason. */
3645 if (name == NULL)
3646 continue;
3649 /* Sanity check that all possibilities were handled. */
3650 if (sec == NULL)
3652 bfd_set_error (bfd_error_bad_value);
3653 goto error_free_vers;
3656 if (bfd_is_und_section (sec)
3657 || bfd_is_com_section (sec))
3658 definition = FALSE;
3659 else
3660 definition = TRUE;
3662 size_change_ok = FALSE;
3663 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
3664 old_alignment = 0;
3665 old_bfd = NULL;
3666 new_sec = sec;
3668 if (is_elf_hash_table (hash_table))
3670 Elf_Internal_Versym iver;
3671 unsigned int vernum = 0;
3672 bfd_boolean skip;
3674 if (ever == NULL)
3676 if (info->default_imported_symver)
3677 /* Use the default symbol version created earlier. */
3678 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3679 else
3680 iver.vs_vers = 0;
3682 else
3683 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3685 vernum = iver.vs_vers & VERSYM_VERSION;
3687 /* If this is a hidden symbol, or if it is not version
3688 1, we append the version name to the symbol name.
3689 However, we do not modify a non-hidden absolute
3690 symbol, because it might be the version symbol
3691 itself. FIXME: What if it isn't? */
3692 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3693 || (vernum > 1 && ! bfd_is_abs_section (sec)))
3695 const char *verstr;
3696 size_t namelen, verlen, newlen;
3697 char *newname, *p;
3699 if (isym->st_shndx != SHN_UNDEF)
3701 if (vernum > elf_tdata (abfd)->cverdefs)
3702 verstr = NULL;
3703 else if (vernum > 1)
3704 verstr =
3705 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3706 else
3707 verstr = "";
3709 if (verstr == NULL)
3711 (*_bfd_error_handler)
3712 (_("%B: %s: invalid version %u (max %d)"),
3713 abfd, name, vernum,
3714 elf_tdata (abfd)->cverdefs);
3715 bfd_set_error (bfd_error_bad_value);
3716 goto error_free_vers;
3719 else
3721 /* We cannot simply test for the number of
3722 entries in the VERNEED section since the
3723 numbers for the needed versions do not start
3724 at 0. */
3725 Elf_Internal_Verneed *t;
3727 verstr = NULL;
3728 for (t = elf_tdata (abfd)->verref;
3729 t != NULL;
3730 t = t->vn_nextref)
3732 Elf_Internal_Vernaux *a;
3734 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3736 if (a->vna_other == vernum)
3738 verstr = a->vna_nodename;
3739 break;
3742 if (a != NULL)
3743 break;
3745 if (verstr == NULL)
3747 (*_bfd_error_handler)
3748 (_("%B: %s: invalid needed version %d"),
3749 abfd, name, vernum);
3750 bfd_set_error (bfd_error_bad_value);
3751 goto error_free_vers;
3755 namelen = strlen (name);
3756 verlen = strlen (verstr);
3757 newlen = namelen + verlen + 2;
3758 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3759 && isym->st_shndx != SHN_UNDEF)
3760 ++newlen;
3762 newname = bfd_alloc (abfd, newlen);
3763 if (newname == NULL)
3764 goto error_free_vers;
3765 memcpy (newname, name, namelen);
3766 p = newname + namelen;
3767 *p++ = ELF_VER_CHR;
3768 /* If this is a defined non-hidden version symbol,
3769 we add another @ to the name. This indicates the
3770 default version of the symbol. */
3771 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3772 && isym->st_shndx != SHN_UNDEF)
3773 *p++ = ELF_VER_CHR;
3774 memcpy (p, verstr, verlen + 1);
3776 name = newname;
3779 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
3780 &value, &old_alignment,
3781 sym_hash, &skip, &override,
3782 &type_change_ok, &size_change_ok))
3783 goto error_free_vers;
3785 if (skip)
3786 continue;
3788 if (override)
3789 definition = FALSE;
3791 h = *sym_hash;
3792 while (h->root.type == bfd_link_hash_indirect
3793 || h->root.type == bfd_link_hash_warning)
3794 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3796 /* Remember the old alignment if this is a common symbol, so
3797 that we don't reduce the alignment later on. We can't
3798 check later, because _bfd_generic_link_add_one_symbol
3799 will set a default for the alignment which we want to
3800 override. We also remember the old bfd where the existing
3801 definition comes from. */
3802 switch (h->root.type)
3804 default:
3805 break;
3807 case bfd_link_hash_defined:
3808 case bfd_link_hash_defweak:
3809 old_bfd = h->root.u.def.section->owner;
3810 break;
3812 case bfd_link_hash_common:
3813 old_bfd = h->root.u.c.p->section->owner;
3814 old_alignment = h->root.u.c.p->alignment_power;
3815 break;
3818 if (elf_tdata (abfd)->verdef != NULL
3819 && ! override
3820 && vernum > 1
3821 && definition)
3822 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3825 if (! (_bfd_generic_link_add_one_symbol
3826 (info, abfd, name, flags, sec, value, NULL, FALSE, collect,
3827 (struct bfd_link_hash_entry **) sym_hash)))
3828 goto error_free_vers;
3830 h = *sym_hash;
3831 while (h->root.type == bfd_link_hash_indirect
3832 || h->root.type == bfd_link_hash_warning)
3833 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3834 *sym_hash = h;
3836 new_weakdef = FALSE;
3837 if (dynamic
3838 && definition
3839 && (flags & BSF_WEAK) != 0
3840 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3841 && is_elf_hash_table (hash_table)
3842 && h->u.weakdef == NULL)
3844 /* Keep a list of all weak defined non function symbols from
3845 a dynamic object, using the weakdef field. Later in this
3846 function we will set the weakdef field to the correct
3847 value. We only put non-function symbols from dynamic
3848 objects on this list, because that happens to be the only
3849 time we need to know the normal symbol corresponding to a
3850 weak symbol, and the information is time consuming to
3851 figure out. If the weakdef field is not already NULL,
3852 then this symbol was already defined by some previous
3853 dynamic object, and we will be using that previous
3854 definition anyhow. */
3856 h->u.weakdef = weaks;
3857 weaks = h;
3858 new_weakdef = TRUE;
3861 /* Set the alignment of a common symbol. */
3862 if ((isym->st_shndx == SHN_COMMON
3863 || bfd_is_com_section (sec))
3864 && h->root.type == bfd_link_hash_common)
3866 unsigned int align;
3868 if (isym->st_shndx == SHN_COMMON)
3869 align = bfd_log2 (isym->st_value);
3870 else
3872 /* The new symbol is a common symbol in a shared object.
3873 We need to get the alignment from the section. */
3874 align = new_sec->alignment_power;
3876 if (align > old_alignment
3877 /* Permit an alignment power of zero if an alignment of one
3878 is specified and no other alignments have been specified. */
3879 || (isym->st_value == 1 && old_alignment == 0))
3880 h->root.u.c.p->alignment_power = align;
3881 else
3882 h->root.u.c.p->alignment_power = old_alignment;
3885 if (is_elf_hash_table (hash_table))
3887 bfd_boolean dynsym;
3889 /* Check the alignment when a common symbol is involved. This
3890 can change when a common symbol is overridden by a normal
3891 definition or a common symbol is ignored due to the old
3892 normal definition. We need to make sure the maximum
3893 alignment is maintained. */
3894 if ((old_alignment || isym->st_shndx == SHN_COMMON)
3895 && h->root.type != bfd_link_hash_common)
3897 unsigned int common_align;
3898 unsigned int normal_align;
3899 unsigned int symbol_align;
3900 bfd *normal_bfd;
3901 bfd *common_bfd;
3903 symbol_align = ffs (h->root.u.def.value) - 1;
3904 if (h->root.u.def.section->owner != NULL
3905 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3907 normal_align = h->root.u.def.section->alignment_power;
3908 if (normal_align > symbol_align)
3909 normal_align = symbol_align;
3911 else
3912 normal_align = symbol_align;
3914 if (old_alignment)
3916 common_align = old_alignment;
3917 common_bfd = old_bfd;
3918 normal_bfd = abfd;
3920 else
3922 common_align = bfd_log2 (isym->st_value);
3923 common_bfd = abfd;
3924 normal_bfd = old_bfd;
3927 if (normal_align < common_align)
3928 (*_bfd_error_handler)
3929 (_("Warning: alignment %u of symbol `%s' in %B"
3930 " is smaller than %u in %B"),
3931 normal_bfd, common_bfd,
3932 1 << normal_align, name, 1 << common_align);
3935 /* Remember the symbol size and type. */
3936 if (isym->st_size != 0
3937 && (definition || h->size == 0))
3939 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3940 (*_bfd_error_handler)
3941 (_("Warning: size of symbol `%s' changed"
3942 " from %lu in %B to %lu in %B"),
3943 old_bfd, abfd,
3944 name, (unsigned long) h->size,
3945 (unsigned long) isym->st_size);
3947 h->size = isym->st_size;
3950 /* If this is a common symbol, then we always want H->SIZE
3951 to be the size of the common symbol. The code just above
3952 won't fix the size if a common symbol becomes larger. We
3953 don't warn about a size change here, because that is
3954 covered by --warn-common. */
3955 if (h->root.type == bfd_link_hash_common)
3956 h->size = h->root.u.c.size;
3958 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3959 && (definition || h->type == STT_NOTYPE))
3961 if (h->type != STT_NOTYPE
3962 && h->type != ELF_ST_TYPE (isym->st_info)
3963 && ! type_change_ok)
3964 (*_bfd_error_handler)
3965 (_("Warning: type of symbol `%s' changed"
3966 " from %d to %d in %B"),
3967 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
3969 h->type = ELF_ST_TYPE (isym->st_info);
3972 /* If st_other has a processor-specific meaning, specific
3973 code might be needed here. We never merge the visibility
3974 attribute with the one from a dynamic object. */
3975 if (bed->elf_backend_merge_symbol_attribute)
3976 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3977 dynamic);
3979 /* If this symbol has default visibility and the user has requested
3980 we not re-export it, then mark it as hidden. */
3981 if (definition && !dynamic
3982 && (abfd->no_export
3983 || (abfd->my_archive && abfd->my_archive->no_export))
3984 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
3985 isym->st_other = STV_HIDDEN | (isym->st_other & ~ ELF_ST_VISIBILITY (-1));
3987 if (isym->st_other != 0 && !dynamic)
3989 unsigned char hvis, symvis, other, nvis;
3991 /* Take the balance of OTHER from the definition. */
3992 other = (definition ? isym->st_other : h->other);
3993 other &= ~ ELF_ST_VISIBILITY (-1);
3995 /* Combine visibilities, using the most constraining one. */
3996 hvis = ELF_ST_VISIBILITY (h->other);
3997 symvis = ELF_ST_VISIBILITY (isym->st_other);
3998 if (! hvis)
3999 nvis = symvis;
4000 else if (! symvis)
4001 nvis = hvis;
4002 else
4003 nvis = hvis < symvis ? hvis : symvis;
4005 h->other = other | nvis;
4008 /* Set a flag in the hash table entry indicating the type of
4009 reference or definition we just found. Keep a count of
4010 the number of dynamic symbols we find. A dynamic symbol
4011 is one which is referenced or defined by both a regular
4012 object and a shared object. */
4013 dynsym = FALSE;
4014 if (! dynamic)
4016 if (! definition)
4018 h->ref_regular = 1;
4019 if (bind != STB_WEAK)
4020 h->ref_regular_nonweak = 1;
4022 else
4023 h->def_regular = 1;
4024 if (! info->executable
4025 || h->def_dynamic
4026 || h->ref_dynamic)
4027 dynsym = TRUE;
4029 else
4031 if (! definition)
4032 h->ref_dynamic = 1;
4033 else
4034 h->def_dynamic = 1;
4035 if (h->def_regular
4036 || h->ref_regular
4037 || (h->u.weakdef != NULL
4038 && ! new_weakdef
4039 && h->u.weakdef->dynindx != -1))
4040 dynsym = TRUE;
4043 /* Check to see if we need to add an indirect symbol for
4044 the default name. */
4045 if (definition || h->root.type == bfd_link_hash_common)
4046 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4047 &sec, &value, &dynsym,
4048 override))
4049 goto error_free_vers;
4051 if (definition && !dynamic)
4053 char *p = strchr (name, ELF_VER_CHR);
4054 if (p != NULL && p[1] != ELF_VER_CHR)
4056 /* Queue non-default versions so that .symver x, x@FOO
4057 aliases can be checked. */
4058 if (! nondeflt_vers)
4060 amt = (isymend - isym + 1)
4061 * sizeof (struct elf_link_hash_entry *);
4062 nondeflt_vers = bfd_malloc (amt);
4064 nondeflt_vers [nondeflt_vers_cnt++] = h;
4068 if (dynsym && h->dynindx == -1)
4070 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4071 goto error_free_vers;
4072 if (h->u.weakdef != NULL
4073 && ! new_weakdef
4074 && h->u.weakdef->dynindx == -1)
4076 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4077 goto error_free_vers;
4080 else if (dynsym && h->dynindx != -1)
4081 /* If the symbol already has a dynamic index, but
4082 visibility says it should not be visible, turn it into
4083 a local symbol. */
4084 switch (ELF_ST_VISIBILITY (h->other))
4086 case STV_INTERNAL:
4087 case STV_HIDDEN:
4088 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4089 dynsym = FALSE;
4090 break;
4093 if (!add_needed
4094 && definition
4095 && dynsym
4096 && h->ref_regular)
4098 int ret;
4099 const char *soname = elf_dt_name (abfd);
4101 /* A symbol from a library loaded via DT_NEEDED of some
4102 other library is referenced by a regular object.
4103 Add a DT_NEEDED entry for it. Issue an error if
4104 --no-add-needed is used. */
4105 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4107 (*_bfd_error_handler)
4108 (_("%s: invalid DSO for symbol `%s' definition"),
4109 abfd, name);
4110 bfd_set_error (bfd_error_bad_value);
4111 goto error_free_vers;
4114 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4116 add_needed = TRUE;
4117 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4118 if (ret < 0)
4119 goto error_free_vers;
4121 BFD_ASSERT (ret == 0);
4126 /* Now that all the symbols from this input file are created, handle
4127 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4128 if (nondeflt_vers != NULL)
4130 bfd_size_type cnt, symidx;
4132 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4134 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4135 char *shortname, *p;
4137 p = strchr (h->root.root.string, ELF_VER_CHR);
4138 if (p == NULL
4139 || (h->root.type != bfd_link_hash_defined
4140 && h->root.type != bfd_link_hash_defweak))
4141 continue;
4143 amt = p - h->root.root.string;
4144 shortname = bfd_malloc (amt + 1);
4145 memcpy (shortname, h->root.root.string, amt);
4146 shortname[amt] = '\0';
4148 hi = (struct elf_link_hash_entry *)
4149 bfd_link_hash_lookup (&hash_table->root, shortname,
4150 FALSE, FALSE, FALSE);
4151 if (hi != NULL
4152 && hi->root.type == h->root.type
4153 && hi->root.u.def.value == h->root.u.def.value
4154 && hi->root.u.def.section == h->root.u.def.section)
4156 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4157 hi->root.type = bfd_link_hash_indirect;
4158 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4159 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
4160 sym_hash = elf_sym_hashes (abfd);
4161 if (sym_hash)
4162 for (symidx = 0; symidx < extsymcount; ++symidx)
4163 if (sym_hash[symidx] == hi)
4165 sym_hash[symidx] = h;
4166 break;
4169 free (shortname);
4171 free (nondeflt_vers);
4172 nondeflt_vers = NULL;
4175 if (extversym != NULL)
4177 free (extversym);
4178 extversym = NULL;
4181 if (isymbuf != NULL)
4182 free (isymbuf);
4183 isymbuf = NULL;
4185 if (!add_needed
4186 && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4188 /* Remove symbols defined in an as-needed shared lib that wasn't
4189 needed. */
4190 struct elf_smash_syms_data inf;
4191 inf.not_needed = abfd;
4192 inf.htab = hash_table;
4193 inf.twiddled = FALSE;
4194 elf_link_hash_traverse (hash_table, elf_smash_syms, &inf);
4195 if (inf.twiddled)
4196 bfd_link_repair_undef_list (&hash_table->root);
4197 weaks = NULL;
4200 /* Now set the weakdefs field correctly for all the weak defined
4201 symbols we found. The only way to do this is to search all the
4202 symbols. Since we only need the information for non functions in
4203 dynamic objects, that's the only time we actually put anything on
4204 the list WEAKS. We need this information so that if a regular
4205 object refers to a symbol defined weakly in a dynamic object, the
4206 real symbol in the dynamic object is also put in the dynamic
4207 symbols; we also must arrange for both symbols to point to the
4208 same memory location. We could handle the general case of symbol
4209 aliasing, but a general symbol alias can only be generated in
4210 assembler code, handling it correctly would be very time
4211 consuming, and other ELF linkers don't handle general aliasing
4212 either. */
4213 if (weaks != NULL)
4215 struct elf_link_hash_entry **hpp;
4216 struct elf_link_hash_entry **hppend;
4217 struct elf_link_hash_entry **sorted_sym_hash;
4218 struct elf_link_hash_entry *h;
4219 size_t sym_count;
4221 /* Since we have to search the whole symbol list for each weak
4222 defined symbol, search time for N weak defined symbols will be
4223 O(N^2). Binary search will cut it down to O(NlogN). */
4224 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4225 sorted_sym_hash = bfd_malloc (amt);
4226 if (sorted_sym_hash == NULL)
4227 goto error_return;
4228 sym_hash = sorted_sym_hash;
4229 hpp = elf_sym_hashes (abfd);
4230 hppend = hpp + extsymcount;
4231 sym_count = 0;
4232 for (; hpp < hppend; hpp++)
4234 h = *hpp;
4235 if (h != NULL
4236 && h->root.type == bfd_link_hash_defined
4237 && h->type != STT_FUNC)
4239 *sym_hash = h;
4240 sym_hash++;
4241 sym_count++;
4245 qsort (sorted_sym_hash, sym_count,
4246 sizeof (struct elf_link_hash_entry *),
4247 elf_sort_symbol);
4249 while (weaks != NULL)
4251 struct elf_link_hash_entry *hlook;
4252 asection *slook;
4253 bfd_vma vlook;
4254 long ilook;
4255 size_t i, j, idx;
4257 hlook = weaks;
4258 weaks = hlook->u.weakdef;
4259 hlook->u.weakdef = NULL;
4261 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4262 || hlook->root.type == bfd_link_hash_defweak
4263 || hlook->root.type == bfd_link_hash_common
4264 || hlook->root.type == bfd_link_hash_indirect);
4265 slook = hlook->root.u.def.section;
4266 vlook = hlook->root.u.def.value;
4268 ilook = -1;
4269 i = 0;
4270 j = sym_count;
4271 while (i < j)
4273 bfd_signed_vma vdiff;
4274 idx = (i + j) / 2;
4275 h = sorted_sym_hash [idx];
4276 vdiff = vlook - h->root.u.def.value;
4277 if (vdiff < 0)
4278 j = idx;
4279 else if (vdiff > 0)
4280 i = idx + 1;
4281 else
4283 long sdiff = slook->id - h->root.u.def.section->id;
4284 if (sdiff < 0)
4285 j = idx;
4286 else if (sdiff > 0)
4287 i = idx + 1;
4288 else
4290 ilook = idx;
4291 break;
4296 /* We didn't find a value/section match. */
4297 if (ilook == -1)
4298 continue;
4300 for (i = ilook; i < sym_count; i++)
4302 h = sorted_sym_hash [i];
4304 /* Stop if value or section doesn't match. */
4305 if (h->root.u.def.value != vlook
4306 || h->root.u.def.section != slook)
4307 break;
4308 else if (h != hlook)
4310 hlook->u.weakdef = h;
4312 /* If the weak definition is in the list of dynamic
4313 symbols, make sure the real definition is put
4314 there as well. */
4315 if (hlook->dynindx != -1 && h->dynindx == -1)
4317 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4318 goto error_return;
4321 /* If the real definition is in the list of dynamic
4322 symbols, make sure the weak definition is put
4323 there as well. If we don't do this, then the
4324 dynamic loader might not merge the entries for the
4325 real definition and the weak definition. */
4326 if (h->dynindx != -1 && hlook->dynindx == -1)
4328 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4329 goto error_return;
4331 break;
4336 free (sorted_sym_hash);
4339 check_directives = get_elf_backend_data (abfd)->check_directives;
4340 if (check_directives)
4341 check_directives (abfd, info);
4343 /* If this object is the same format as the output object, and it is
4344 not a shared library, then let the backend look through the
4345 relocs.
4347 This is required to build global offset table entries and to
4348 arrange for dynamic relocs. It is not required for the
4349 particular common case of linking non PIC code, even when linking
4350 against shared libraries, but unfortunately there is no way of
4351 knowing whether an object file has been compiled PIC or not.
4352 Looking through the relocs is not particularly time consuming.
4353 The problem is that we must either (1) keep the relocs in memory,
4354 which causes the linker to require additional runtime memory or
4355 (2) read the relocs twice from the input file, which wastes time.
4356 This would be a good case for using mmap.
4358 I have no idea how to handle linking PIC code into a file of a
4359 different format. It probably can't be done. */
4360 check_relocs = get_elf_backend_data (abfd)->check_relocs;
4361 if (! dynamic
4362 && is_elf_hash_table (hash_table)
4363 && hash_table->root.creator == abfd->xvec
4364 && check_relocs != NULL)
4366 asection *o;
4368 for (o = abfd->sections; o != NULL; o = o->next)
4370 Elf_Internal_Rela *internal_relocs;
4371 bfd_boolean ok;
4373 if ((o->flags & SEC_RELOC) == 0
4374 || o->reloc_count == 0
4375 || ((info->strip == strip_all || info->strip == strip_debugger)
4376 && (o->flags & SEC_DEBUGGING) != 0)
4377 || bfd_is_abs_section (o->output_section))
4378 continue;
4380 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4381 info->keep_memory);
4382 if (internal_relocs == NULL)
4383 goto error_return;
4385 ok = (*check_relocs) (abfd, info, o, internal_relocs);
4387 if (elf_section_data (o)->relocs != internal_relocs)
4388 free (internal_relocs);
4390 if (! ok)
4391 goto error_return;
4395 /* If this is a non-traditional link, try to optimize the handling
4396 of the .stab/.stabstr sections. */
4397 if (! dynamic
4398 && ! info->traditional_format
4399 && is_elf_hash_table (hash_table)
4400 && (info->strip != strip_all && info->strip != strip_debugger))
4402 asection *stabstr;
4404 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4405 if (stabstr != NULL)
4407 bfd_size_type string_offset = 0;
4408 asection *stab;
4410 for (stab = abfd->sections; stab; stab = stab->next)
4411 if (strncmp (".stab", stab->name, 5) == 0
4412 && (!stab->name[5] ||
4413 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4414 && (stab->flags & SEC_MERGE) == 0
4415 && !bfd_is_abs_section (stab->output_section))
4417 struct bfd_elf_section_data *secdata;
4419 secdata = elf_section_data (stab);
4420 if (! _bfd_link_section_stabs (abfd,
4421 &hash_table->stab_info,
4422 stab, stabstr,
4423 &secdata->sec_info,
4424 &string_offset))
4425 goto error_return;
4426 if (secdata->sec_info)
4427 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4432 if (is_elf_hash_table (hash_table) && add_needed)
4434 /* Add this bfd to the loaded list. */
4435 struct elf_link_loaded_list *n;
4437 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4438 if (n == NULL)
4439 goto error_return;
4440 n->abfd = abfd;
4441 n->next = hash_table->loaded;
4442 hash_table->loaded = n;
4445 return TRUE;
4447 error_free_vers:
4448 if (nondeflt_vers != NULL)
4449 free (nondeflt_vers);
4450 if (extversym != NULL)
4451 free (extversym);
4452 error_free_sym:
4453 if (isymbuf != NULL)
4454 free (isymbuf);
4455 error_return:
4456 return FALSE;
4459 /* Return the linker hash table entry of a symbol that might be
4460 satisfied by an archive symbol. Return -1 on error. */
4462 struct elf_link_hash_entry *
4463 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4464 struct bfd_link_info *info,
4465 const char *name)
4467 struct elf_link_hash_entry *h;
4468 char *p, *copy;
4469 size_t len, first;
4471 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4472 if (h != NULL)
4473 return h;
4475 /* If this is a default version (the name contains @@), look up the
4476 symbol again with only one `@' as well as without the version.
4477 The effect is that references to the symbol with and without the
4478 version will be matched by the default symbol in the archive. */
4480 p = strchr (name, ELF_VER_CHR);
4481 if (p == NULL || p[1] != ELF_VER_CHR)
4482 return h;
4484 /* First check with only one `@'. */
4485 len = strlen (name);
4486 copy = bfd_alloc (abfd, len);
4487 if (copy == NULL)
4488 return (struct elf_link_hash_entry *) 0 - 1;
4490 first = p - name + 1;
4491 memcpy (copy, name, first);
4492 memcpy (copy + first, name + first + 1, len - first);
4494 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4495 if (h == NULL)
4497 /* We also need to check references to the symbol without the
4498 version. */
4499 copy[first - 1] = '\0';
4500 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4501 FALSE, FALSE, FALSE);
4504 bfd_release (abfd, copy);
4505 return h;
4508 /* Add symbols from an ELF archive file to the linker hash table. We
4509 don't use _bfd_generic_link_add_archive_symbols because of a
4510 problem which arises on UnixWare. The UnixWare libc.so is an
4511 archive which includes an entry libc.so.1 which defines a bunch of
4512 symbols. The libc.so archive also includes a number of other
4513 object files, which also define symbols, some of which are the same
4514 as those defined in libc.so.1. Correct linking requires that we
4515 consider each object file in turn, and include it if it defines any
4516 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4517 this; it looks through the list of undefined symbols, and includes
4518 any object file which defines them. When this algorithm is used on
4519 UnixWare, it winds up pulling in libc.so.1 early and defining a
4520 bunch of symbols. This means that some of the other objects in the
4521 archive are not included in the link, which is incorrect since they
4522 precede libc.so.1 in the archive.
4524 Fortunately, ELF archive handling is simpler than that done by
4525 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4526 oddities. In ELF, if we find a symbol in the archive map, and the
4527 symbol is currently undefined, we know that we must pull in that
4528 object file.
4530 Unfortunately, we do have to make multiple passes over the symbol
4531 table until nothing further is resolved. */
4533 static bfd_boolean
4534 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4536 symindex c;
4537 bfd_boolean *defined = NULL;
4538 bfd_boolean *included = NULL;
4539 carsym *symdefs;
4540 bfd_boolean loop;
4541 bfd_size_type amt;
4542 const struct elf_backend_data *bed;
4543 struct elf_link_hash_entry * (*archive_symbol_lookup)
4544 (bfd *, struct bfd_link_info *, const char *);
4546 if (! bfd_has_map (abfd))
4548 /* An empty archive is a special case. */
4549 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4550 return TRUE;
4551 bfd_set_error (bfd_error_no_armap);
4552 return FALSE;
4555 /* Keep track of all symbols we know to be already defined, and all
4556 files we know to be already included. This is to speed up the
4557 second and subsequent passes. */
4558 c = bfd_ardata (abfd)->symdef_count;
4559 if (c == 0)
4560 return TRUE;
4561 amt = c;
4562 amt *= sizeof (bfd_boolean);
4563 defined = bfd_zmalloc (amt);
4564 included = bfd_zmalloc (amt);
4565 if (defined == NULL || included == NULL)
4566 goto error_return;
4568 symdefs = bfd_ardata (abfd)->symdefs;
4569 bed = get_elf_backend_data (abfd);
4570 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4574 file_ptr last;
4575 symindex i;
4576 carsym *symdef;
4577 carsym *symdefend;
4579 loop = FALSE;
4580 last = -1;
4582 symdef = symdefs;
4583 symdefend = symdef + c;
4584 for (i = 0; symdef < symdefend; symdef++, i++)
4586 struct elf_link_hash_entry *h;
4587 bfd *element;
4588 struct bfd_link_hash_entry *undefs_tail;
4589 symindex mark;
4591 if (defined[i] || included[i])
4592 continue;
4593 if (symdef->file_offset == last)
4595 included[i] = TRUE;
4596 continue;
4599 h = archive_symbol_lookup (abfd, info, symdef->name);
4600 if (h == (struct elf_link_hash_entry *) 0 - 1)
4601 goto error_return;
4603 if (h == NULL)
4604 continue;
4606 if (h->root.type == bfd_link_hash_common)
4608 /* We currently have a common symbol. The archive map contains
4609 a reference to this symbol, so we may want to include it. We
4610 only want to include it however, if this archive element
4611 contains a definition of the symbol, not just another common
4612 declaration of it.
4614 Unfortunately some archivers (including GNU ar) will put
4615 declarations of common symbols into their archive maps, as
4616 well as real definitions, so we cannot just go by the archive
4617 map alone. Instead we must read in the element's symbol
4618 table and check that to see what kind of symbol definition
4619 this is. */
4620 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4621 continue;
4623 else if (h->root.type != bfd_link_hash_undefined)
4625 if (h->root.type != bfd_link_hash_undefweak)
4626 defined[i] = TRUE;
4627 continue;
4630 /* We need to include this archive member. */
4631 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4632 if (element == NULL)
4633 goto error_return;
4635 if (! bfd_check_format (element, bfd_object))
4636 goto error_return;
4638 /* Doublecheck that we have not included this object
4639 already--it should be impossible, but there may be
4640 something wrong with the archive. */
4641 if (element->archive_pass != 0)
4643 bfd_set_error (bfd_error_bad_value);
4644 goto error_return;
4646 element->archive_pass = 1;
4648 undefs_tail = info->hash->undefs_tail;
4650 if (! (*info->callbacks->add_archive_element) (info, element,
4651 symdef->name))
4652 goto error_return;
4653 if (! bfd_link_add_symbols (element, info))
4654 goto error_return;
4656 /* If there are any new undefined symbols, we need to make
4657 another pass through the archive in order to see whether
4658 they can be defined. FIXME: This isn't perfect, because
4659 common symbols wind up on undefs_tail and because an
4660 undefined symbol which is defined later on in this pass
4661 does not require another pass. This isn't a bug, but it
4662 does make the code less efficient than it could be. */
4663 if (undefs_tail != info->hash->undefs_tail)
4664 loop = TRUE;
4666 /* Look backward to mark all symbols from this object file
4667 which we have already seen in this pass. */
4668 mark = i;
4671 included[mark] = TRUE;
4672 if (mark == 0)
4673 break;
4674 --mark;
4676 while (symdefs[mark].file_offset == symdef->file_offset);
4678 /* We mark subsequent symbols from this object file as we go
4679 on through the loop. */
4680 last = symdef->file_offset;
4683 while (loop);
4685 free (defined);
4686 free (included);
4688 return TRUE;
4690 error_return:
4691 if (defined != NULL)
4692 free (defined);
4693 if (included != NULL)
4694 free (included);
4695 return FALSE;
4698 /* Given an ELF BFD, add symbols to the global hash table as
4699 appropriate. */
4701 bfd_boolean
4702 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4704 switch (bfd_get_format (abfd))
4706 case bfd_object:
4707 return elf_link_add_object_symbols (abfd, info);
4708 case bfd_archive:
4709 return elf_link_add_archive_symbols (abfd, info);
4710 default:
4711 bfd_set_error (bfd_error_wrong_format);
4712 return FALSE;
4716 /* This function will be called though elf_link_hash_traverse to store
4717 all hash value of the exported symbols in an array. */
4719 static bfd_boolean
4720 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4722 unsigned long **valuep = data;
4723 const char *name;
4724 char *p;
4725 unsigned long ha;
4726 char *alc = NULL;
4728 if (h->root.type == bfd_link_hash_warning)
4729 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4731 /* Ignore indirect symbols. These are added by the versioning code. */
4732 if (h->dynindx == -1)
4733 return TRUE;
4735 name = h->root.root.string;
4736 p = strchr (name, ELF_VER_CHR);
4737 if (p != NULL)
4739 alc = bfd_malloc (p - name + 1);
4740 memcpy (alc, name, p - name);
4741 alc[p - name] = '\0';
4742 name = alc;
4745 /* Compute the hash value. */
4746 ha = bfd_elf_hash (name);
4748 /* Store the found hash value in the array given as the argument. */
4749 *(*valuep)++ = ha;
4751 /* And store it in the struct so that we can put it in the hash table
4752 later. */
4753 h->u.elf_hash_value = ha;
4755 if (alc != NULL)
4756 free (alc);
4758 return TRUE;
4761 /* Array used to determine the number of hash table buckets to use
4762 based on the number of symbols there are. If there are fewer than
4763 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4764 fewer than 37 we use 17 buckets, and so forth. We never use more
4765 than 32771 buckets. */
4767 static const size_t elf_buckets[] =
4769 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4770 16411, 32771, 0
4773 /* Compute bucket count for hashing table. We do not use a static set
4774 of possible tables sizes anymore. Instead we determine for all
4775 possible reasonable sizes of the table the outcome (i.e., the
4776 number of collisions etc) and choose the best solution. The
4777 weighting functions are not too simple to allow the table to grow
4778 without bounds. Instead one of the weighting factors is the size.
4779 Therefore the result is always a good payoff between few collisions
4780 (= short chain lengths) and table size. */
4781 static size_t
4782 compute_bucket_count (struct bfd_link_info *info)
4784 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4785 size_t best_size = 0;
4786 unsigned long int *hashcodes;
4787 unsigned long int *hashcodesp;
4788 unsigned long int i;
4789 bfd_size_type amt;
4791 /* Compute the hash values for all exported symbols. At the same
4792 time store the values in an array so that we could use them for
4793 optimizations. */
4794 amt = dynsymcount;
4795 amt *= sizeof (unsigned long int);
4796 hashcodes = bfd_malloc (amt);
4797 if (hashcodes == NULL)
4798 return 0;
4799 hashcodesp = hashcodes;
4801 /* Put all hash values in HASHCODES. */
4802 elf_link_hash_traverse (elf_hash_table (info),
4803 elf_collect_hash_codes, &hashcodesp);
4805 /* We have a problem here. The following code to optimize the table
4806 size requires an integer type with more the 32 bits. If
4807 BFD_HOST_U_64_BIT is set we know about such a type. */
4808 #ifdef BFD_HOST_U_64_BIT
4809 if (info->optimize)
4811 unsigned long int nsyms = hashcodesp - hashcodes;
4812 size_t minsize;
4813 size_t maxsize;
4814 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4815 unsigned long int *counts ;
4816 bfd *dynobj = elf_hash_table (info)->dynobj;
4817 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4819 /* Possible optimization parameters: if we have NSYMS symbols we say
4820 that the hashing table must at least have NSYMS/4 and at most
4821 2*NSYMS buckets. */
4822 minsize = nsyms / 4;
4823 if (minsize == 0)
4824 minsize = 1;
4825 best_size = maxsize = nsyms * 2;
4827 /* Create array where we count the collisions in. We must use bfd_malloc
4828 since the size could be large. */
4829 amt = maxsize;
4830 amt *= sizeof (unsigned long int);
4831 counts = bfd_malloc (amt);
4832 if (counts == NULL)
4834 free (hashcodes);
4835 return 0;
4838 /* Compute the "optimal" size for the hash table. The criteria is a
4839 minimal chain length. The minor criteria is (of course) the size
4840 of the table. */
4841 for (i = minsize; i < maxsize; ++i)
4843 /* Walk through the array of hashcodes and count the collisions. */
4844 BFD_HOST_U_64_BIT max;
4845 unsigned long int j;
4846 unsigned long int fact;
4848 memset (counts, '\0', i * sizeof (unsigned long int));
4850 /* Determine how often each hash bucket is used. */
4851 for (j = 0; j < nsyms; ++j)
4852 ++counts[hashcodes[j] % i];
4854 /* For the weight function we need some information about the
4855 pagesize on the target. This is information need not be 100%
4856 accurate. Since this information is not available (so far) we
4857 define it here to a reasonable default value. If it is crucial
4858 to have a better value some day simply define this value. */
4859 # ifndef BFD_TARGET_PAGESIZE
4860 # define BFD_TARGET_PAGESIZE (4096)
4861 # endif
4863 /* We in any case need 2 + NSYMS entries for the size values and
4864 the chains. */
4865 max = (2 + nsyms) * (bed->s->arch_size / 8);
4867 # if 1
4868 /* Variant 1: optimize for short chains. We add the squares
4869 of all the chain lengths (which favors many small chain
4870 over a few long chains). */
4871 for (j = 0; j < i; ++j)
4872 max += counts[j] * counts[j];
4874 /* This adds penalties for the overall size of the table. */
4875 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4876 max *= fact * fact;
4877 # else
4878 /* Variant 2: Optimize a lot more for small table. Here we
4879 also add squares of the size but we also add penalties for
4880 empty slots (the +1 term). */
4881 for (j = 0; j < i; ++j)
4882 max += (1 + counts[j]) * (1 + counts[j]);
4884 /* The overall size of the table is considered, but not as
4885 strong as in variant 1, where it is squared. */
4886 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4887 max *= fact;
4888 # endif
4890 /* Compare with current best results. */
4891 if (max < best_chlen)
4893 best_chlen = max;
4894 best_size = i;
4898 free (counts);
4900 else
4901 #endif /* defined (BFD_HOST_U_64_BIT) */
4903 /* This is the fallback solution if no 64bit type is available or if we
4904 are not supposed to spend much time on optimizations. We select the
4905 bucket count using a fixed set of numbers. */
4906 for (i = 0; elf_buckets[i] != 0; i++)
4908 best_size = elf_buckets[i];
4909 if (dynsymcount < elf_buckets[i + 1])
4910 break;
4914 /* Free the arrays we needed. */
4915 free (hashcodes);
4917 return best_size;
4920 /* Set up the sizes and contents of the ELF dynamic sections. This is
4921 called by the ELF linker emulation before_allocation routine. We
4922 must set the sizes of the sections before the linker sets the
4923 addresses of the various sections. */
4925 bfd_boolean
4926 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4927 const char *soname,
4928 const char *rpath,
4929 const char *filter_shlib,
4930 const char * const *auxiliary_filters,
4931 struct bfd_link_info *info,
4932 asection **sinterpptr,
4933 struct bfd_elf_version_tree *verdefs)
4935 bfd_size_type soname_indx;
4936 bfd *dynobj;
4937 const struct elf_backend_data *bed;
4938 struct elf_assign_sym_version_info asvinfo;
4940 *sinterpptr = NULL;
4942 soname_indx = (bfd_size_type) -1;
4944 if (!is_elf_hash_table (info->hash))
4945 return TRUE;
4947 elf_tdata (output_bfd)->relro = info->relro;
4948 if (info->execstack)
4949 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4950 else if (info->noexecstack)
4951 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4952 else
4954 bfd *inputobj;
4955 asection *notesec = NULL;
4956 int exec = 0;
4958 for (inputobj = info->input_bfds;
4959 inputobj;
4960 inputobj = inputobj->link_next)
4962 asection *s;
4964 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
4965 continue;
4966 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
4967 if (s)
4969 if (s->flags & SEC_CODE)
4970 exec = PF_X;
4971 notesec = s;
4973 else
4974 exec = PF_X;
4976 if (notesec)
4978 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
4979 if (exec && info->relocatable
4980 && notesec->output_section != bfd_abs_section_ptr)
4981 notesec->output_section->flags |= SEC_CODE;
4985 /* Any syms created from now on start with -1 in
4986 got.refcount/offset and plt.refcount/offset. */
4987 elf_hash_table (info)->init_refcount = elf_hash_table (info)->init_offset;
4989 /* The backend may have to create some sections regardless of whether
4990 we're dynamic or not. */
4991 bed = get_elf_backend_data (output_bfd);
4992 if (bed->elf_backend_always_size_sections
4993 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
4994 return FALSE;
4996 dynobj = elf_hash_table (info)->dynobj;
4998 /* If there were no dynamic objects in the link, there is nothing to
4999 do here. */
5000 if (dynobj == NULL)
5001 return TRUE;
5003 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5004 return FALSE;
5006 if (elf_hash_table (info)->dynamic_sections_created)
5008 struct elf_info_failed eif;
5009 struct elf_link_hash_entry *h;
5010 asection *dynstr;
5011 struct bfd_elf_version_tree *t;
5012 struct bfd_elf_version_expr *d;
5013 bfd_boolean all_defined;
5015 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5016 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5018 if (soname != NULL)
5020 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5021 soname, TRUE);
5022 if (soname_indx == (bfd_size_type) -1
5023 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5024 return FALSE;
5027 if (info->symbolic)
5029 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5030 return FALSE;
5031 info->flags |= DF_SYMBOLIC;
5034 if (rpath != NULL)
5036 bfd_size_type indx;
5038 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5039 TRUE);
5040 if (indx == (bfd_size_type) -1
5041 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5042 return FALSE;
5044 if (info->new_dtags)
5046 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5047 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5048 return FALSE;
5052 if (filter_shlib != NULL)
5054 bfd_size_type indx;
5056 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5057 filter_shlib, TRUE);
5058 if (indx == (bfd_size_type) -1
5059 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5060 return FALSE;
5063 if (auxiliary_filters != NULL)
5065 const char * const *p;
5067 for (p = auxiliary_filters; *p != NULL; p++)
5069 bfd_size_type indx;
5071 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5072 *p, TRUE);
5073 if (indx == (bfd_size_type) -1
5074 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5075 return FALSE;
5079 eif.info = info;
5080 eif.verdefs = verdefs;
5081 eif.failed = FALSE;
5083 /* If we are supposed to export all symbols into the dynamic symbol
5084 table (this is not the normal case), then do so. */
5085 if (info->export_dynamic)
5087 elf_link_hash_traverse (elf_hash_table (info),
5088 _bfd_elf_export_symbol,
5089 &eif);
5090 if (eif.failed)
5091 return FALSE;
5094 /* Make all global versions with definition. */
5095 for (t = verdefs; t != NULL; t = t->next)
5096 for (d = t->globals.list; d != NULL; d = d->next)
5097 if (!d->symver && d->symbol)
5099 const char *verstr, *name;
5100 size_t namelen, verlen, newlen;
5101 char *newname, *p;
5102 struct elf_link_hash_entry *newh;
5104 name = d->symbol;
5105 namelen = strlen (name);
5106 verstr = t->name;
5107 verlen = strlen (verstr);
5108 newlen = namelen + verlen + 3;
5110 newname = bfd_malloc (newlen);
5111 if (newname == NULL)
5112 return FALSE;
5113 memcpy (newname, name, namelen);
5115 /* Check the hidden versioned definition. */
5116 p = newname + namelen;
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);
5122 if (newh == NULL
5123 || (newh->root.type != bfd_link_hash_defined
5124 && newh->root.type != bfd_link_hash_defweak))
5126 /* Check the default versioned definition. */
5127 *p++ = ELF_VER_CHR;
5128 memcpy (p, verstr, verlen + 1);
5129 newh = elf_link_hash_lookup (elf_hash_table (info),
5130 newname, FALSE, FALSE,
5131 FALSE);
5133 free (newname);
5135 /* Mark this version if there is a definition and it is
5136 not defined in a shared object. */
5137 if (newh != NULL
5138 && !newh->def_dynamic
5139 && (newh->root.type == bfd_link_hash_defined
5140 || newh->root.type == bfd_link_hash_defweak))
5141 d->symver = 1;
5144 /* Attach all the symbols to their version information. */
5145 asvinfo.output_bfd = output_bfd;
5146 asvinfo.info = info;
5147 asvinfo.verdefs = verdefs;
5148 asvinfo.failed = FALSE;
5150 elf_link_hash_traverse (elf_hash_table (info),
5151 _bfd_elf_link_assign_sym_version,
5152 &asvinfo);
5153 if (asvinfo.failed)
5154 return FALSE;
5156 if (!info->allow_undefined_version)
5158 /* Check if all global versions have a definition. */
5159 all_defined = TRUE;
5160 for (t = verdefs; t != NULL; t = t->next)
5161 for (d = t->globals.list; d != NULL; d = d->next)
5162 if (!d->symver && !d->script)
5164 (*_bfd_error_handler)
5165 (_("%s: undefined version: %s"),
5166 d->pattern, t->name);
5167 all_defined = FALSE;
5170 if (!all_defined)
5172 bfd_set_error (bfd_error_bad_value);
5173 return FALSE;
5177 /* Find all symbols which were defined in a dynamic object and make
5178 the backend pick a reasonable value for them. */
5179 elf_link_hash_traverse (elf_hash_table (info),
5180 _bfd_elf_adjust_dynamic_symbol,
5181 &eif);
5182 if (eif.failed)
5183 return FALSE;
5185 /* Add some entries to the .dynamic section. We fill in some of the
5186 values later, in bfd_elf_final_link, but we must add the entries
5187 now so that we know the final size of the .dynamic section. */
5189 /* If there are initialization and/or finalization functions to
5190 call then add the corresponding DT_INIT/DT_FINI entries. */
5191 h = (info->init_function
5192 ? elf_link_hash_lookup (elf_hash_table (info),
5193 info->init_function, FALSE,
5194 FALSE, FALSE)
5195 : NULL);
5196 if (h != NULL
5197 && (h->ref_regular
5198 || h->def_regular))
5200 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5201 return FALSE;
5203 h = (info->fini_function
5204 ? elf_link_hash_lookup (elf_hash_table (info),
5205 info->fini_function, FALSE,
5206 FALSE, FALSE)
5207 : NULL);
5208 if (h != NULL
5209 && (h->ref_regular
5210 || h->def_regular))
5212 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5213 return FALSE;
5216 if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL)
5218 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5219 if (! info->executable)
5221 bfd *sub;
5222 asection *o;
5224 for (sub = info->input_bfds; sub != NULL;
5225 sub = sub->link_next)
5226 for (o = sub->sections; o != NULL; o = o->next)
5227 if (elf_section_data (o)->this_hdr.sh_type
5228 == SHT_PREINIT_ARRAY)
5230 (*_bfd_error_handler)
5231 (_("%B: .preinit_array section is not allowed in DSO"),
5232 sub);
5233 break;
5236 bfd_set_error (bfd_error_nonrepresentable_section);
5237 return FALSE;
5240 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5241 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5242 return FALSE;
5244 if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL)
5246 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5247 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5248 return FALSE;
5250 if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL)
5252 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5253 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5254 return FALSE;
5257 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5258 /* If .dynstr is excluded from the link, we don't want any of
5259 these tags. Strictly, we should be checking each section
5260 individually; This quick check covers for the case where
5261 someone does a /DISCARD/ : { *(*) }. */
5262 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5264 bfd_size_type strsize;
5266 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5267 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
5268 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5269 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5270 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5271 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5272 bed->s->sizeof_sym))
5273 return FALSE;
5277 /* The backend must work out the sizes of all the other dynamic
5278 sections. */
5279 if (bed->elf_backend_size_dynamic_sections
5280 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5281 return FALSE;
5283 if (elf_hash_table (info)->dynamic_sections_created)
5285 bfd_size_type dynsymcount;
5286 unsigned long section_sym_count;
5287 asection *s;
5288 size_t bucketcount = 0;
5289 size_t hash_entry_size;
5290 unsigned int dtagcount;
5292 /* Set up the version definition section. */
5293 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5294 BFD_ASSERT (s != NULL);
5296 /* We may have created additional version definitions if we are
5297 just linking a regular application. */
5298 verdefs = asvinfo.verdefs;
5300 /* Skip anonymous version tag. */
5301 if (verdefs != NULL && verdefs->vernum == 0)
5302 verdefs = verdefs->next;
5304 if (verdefs == NULL && !info->create_default_symver)
5305 _bfd_strip_section_from_output (info, s);
5306 else
5308 unsigned int cdefs;
5309 bfd_size_type size;
5310 struct bfd_elf_version_tree *t;
5311 bfd_byte *p;
5312 Elf_Internal_Verdef def;
5313 Elf_Internal_Verdaux defaux;
5314 struct bfd_link_hash_entry *bh;
5315 struct elf_link_hash_entry *h;
5316 const char *name;
5318 cdefs = 0;
5319 size = 0;
5321 /* Make space for the base version. */
5322 size += sizeof (Elf_External_Verdef);
5323 size += sizeof (Elf_External_Verdaux);
5324 ++cdefs;
5326 /* Make space for the default version. */
5327 if (info->create_default_symver)
5329 size += sizeof (Elf_External_Verdef);
5330 ++cdefs;
5333 for (t = verdefs; t != NULL; t = t->next)
5335 struct bfd_elf_version_deps *n;
5337 size += sizeof (Elf_External_Verdef);
5338 size += sizeof (Elf_External_Verdaux);
5339 ++cdefs;
5341 for (n = t->deps; n != NULL; n = n->next)
5342 size += sizeof (Elf_External_Verdaux);
5345 s->size = size;
5346 s->contents = bfd_alloc (output_bfd, s->size);
5347 if (s->contents == NULL && s->size != 0)
5348 return FALSE;
5350 /* Fill in the version definition section. */
5352 p = s->contents;
5354 def.vd_version = VER_DEF_CURRENT;
5355 def.vd_flags = VER_FLG_BASE;
5356 def.vd_ndx = 1;
5357 def.vd_cnt = 1;
5358 if (info->create_default_symver)
5360 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5361 def.vd_next = sizeof (Elf_External_Verdef);
5363 else
5365 def.vd_aux = sizeof (Elf_External_Verdef);
5366 def.vd_next = (sizeof (Elf_External_Verdef)
5367 + sizeof (Elf_External_Verdaux));
5370 if (soname_indx != (bfd_size_type) -1)
5372 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5373 soname_indx);
5374 def.vd_hash = bfd_elf_hash (soname);
5375 defaux.vda_name = soname_indx;
5376 name = soname;
5378 else
5380 bfd_size_type indx;
5382 name = basename (output_bfd->filename);
5383 def.vd_hash = bfd_elf_hash (name);
5384 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5385 name, FALSE);
5386 if (indx == (bfd_size_type) -1)
5387 return FALSE;
5388 defaux.vda_name = indx;
5390 defaux.vda_next = 0;
5392 _bfd_elf_swap_verdef_out (output_bfd, &def,
5393 (Elf_External_Verdef *) p);
5394 p += sizeof (Elf_External_Verdef);
5395 if (info->create_default_symver)
5397 /* Add a symbol representing this version. */
5398 bh = NULL;
5399 if (! (_bfd_generic_link_add_one_symbol
5400 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5401 0, NULL, FALSE,
5402 get_elf_backend_data (dynobj)->collect, &bh)))
5403 return FALSE;
5404 h = (struct elf_link_hash_entry *) bh;
5405 h->non_elf = 0;
5406 h->def_regular = 1;
5407 h->type = STT_OBJECT;
5408 h->verinfo.vertree = NULL;
5410 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5411 return FALSE;
5413 /* Create a duplicate of the base version with the same
5414 aux block, but different flags. */
5415 def.vd_flags = 0;
5416 def.vd_ndx = 2;
5417 def.vd_aux = sizeof (Elf_External_Verdef);
5418 if (verdefs)
5419 def.vd_next = (sizeof (Elf_External_Verdef)
5420 + sizeof (Elf_External_Verdaux));
5421 else
5422 def.vd_next = 0;
5423 _bfd_elf_swap_verdef_out (output_bfd, &def,
5424 (Elf_External_Verdef *) p);
5425 p += sizeof (Elf_External_Verdef);
5427 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5428 (Elf_External_Verdaux *) p);
5429 p += sizeof (Elf_External_Verdaux);
5431 for (t = verdefs; t != NULL; t = t->next)
5433 unsigned int cdeps;
5434 struct bfd_elf_version_deps *n;
5436 cdeps = 0;
5437 for (n = t->deps; n != NULL; n = n->next)
5438 ++cdeps;
5440 /* Add a symbol representing this version. */
5441 bh = NULL;
5442 if (! (_bfd_generic_link_add_one_symbol
5443 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5444 0, NULL, FALSE,
5445 get_elf_backend_data (dynobj)->collect, &bh)))
5446 return FALSE;
5447 h = (struct elf_link_hash_entry *) bh;
5448 h->non_elf = 0;
5449 h->def_regular = 1;
5450 h->type = STT_OBJECT;
5451 h->verinfo.vertree = t;
5453 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5454 return FALSE;
5456 def.vd_version = VER_DEF_CURRENT;
5457 def.vd_flags = 0;
5458 if (t->globals.list == NULL
5459 && t->locals.list == NULL
5460 && ! t->used)
5461 def.vd_flags |= VER_FLG_WEAK;
5462 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5463 def.vd_cnt = cdeps + 1;
5464 def.vd_hash = bfd_elf_hash (t->name);
5465 def.vd_aux = sizeof (Elf_External_Verdef);
5466 def.vd_next = 0;
5467 if (t->next != NULL)
5468 def.vd_next = (sizeof (Elf_External_Verdef)
5469 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5471 _bfd_elf_swap_verdef_out (output_bfd, &def,
5472 (Elf_External_Verdef *) p);
5473 p += sizeof (Elf_External_Verdef);
5475 defaux.vda_name = h->dynstr_index;
5476 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5477 h->dynstr_index);
5478 defaux.vda_next = 0;
5479 if (t->deps != NULL)
5480 defaux.vda_next = sizeof (Elf_External_Verdaux);
5481 t->name_indx = defaux.vda_name;
5483 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5484 (Elf_External_Verdaux *) p);
5485 p += sizeof (Elf_External_Verdaux);
5487 for (n = t->deps; n != NULL; n = n->next)
5489 if (n->version_needed == NULL)
5491 /* This can happen if there was an error in the
5492 version script. */
5493 defaux.vda_name = 0;
5495 else
5497 defaux.vda_name = n->version_needed->name_indx;
5498 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5499 defaux.vda_name);
5501 if (n->next == NULL)
5502 defaux.vda_next = 0;
5503 else
5504 defaux.vda_next = sizeof (Elf_External_Verdaux);
5506 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5507 (Elf_External_Verdaux *) p);
5508 p += sizeof (Elf_External_Verdaux);
5512 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5513 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5514 return FALSE;
5516 elf_tdata (output_bfd)->cverdefs = cdefs;
5519 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5521 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5522 return FALSE;
5524 else if (info->flags & DF_BIND_NOW)
5526 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5527 return FALSE;
5530 if (info->flags_1)
5532 if (info->executable)
5533 info->flags_1 &= ~ (DF_1_INITFIRST
5534 | DF_1_NODELETE
5535 | DF_1_NOOPEN);
5536 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5537 return FALSE;
5540 /* Work out the size of the version reference section. */
5542 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5543 BFD_ASSERT (s != NULL);
5545 struct elf_find_verdep_info sinfo;
5547 sinfo.output_bfd = output_bfd;
5548 sinfo.info = info;
5549 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5550 if (sinfo.vers == 0)
5551 sinfo.vers = 1;
5552 sinfo.failed = FALSE;
5554 elf_link_hash_traverse (elf_hash_table (info),
5555 _bfd_elf_link_find_version_dependencies,
5556 &sinfo);
5558 if (elf_tdata (output_bfd)->verref == NULL)
5559 _bfd_strip_section_from_output (info, s);
5560 else
5562 Elf_Internal_Verneed *t;
5563 unsigned int size;
5564 unsigned int crefs;
5565 bfd_byte *p;
5567 /* Build the version definition section. */
5568 size = 0;
5569 crefs = 0;
5570 for (t = elf_tdata (output_bfd)->verref;
5571 t != NULL;
5572 t = t->vn_nextref)
5574 Elf_Internal_Vernaux *a;
5576 size += sizeof (Elf_External_Verneed);
5577 ++crefs;
5578 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5579 size += sizeof (Elf_External_Vernaux);
5582 s->size = size;
5583 s->contents = bfd_alloc (output_bfd, s->size);
5584 if (s->contents == NULL)
5585 return FALSE;
5587 p = s->contents;
5588 for (t = elf_tdata (output_bfd)->verref;
5589 t != NULL;
5590 t = t->vn_nextref)
5592 unsigned int caux;
5593 Elf_Internal_Vernaux *a;
5594 bfd_size_type indx;
5596 caux = 0;
5597 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5598 ++caux;
5600 t->vn_version = VER_NEED_CURRENT;
5601 t->vn_cnt = caux;
5602 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5603 elf_dt_name (t->vn_bfd) != NULL
5604 ? elf_dt_name (t->vn_bfd)
5605 : basename (t->vn_bfd->filename),
5606 FALSE);
5607 if (indx == (bfd_size_type) -1)
5608 return FALSE;
5609 t->vn_file = indx;
5610 t->vn_aux = sizeof (Elf_External_Verneed);
5611 if (t->vn_nextref == NULL)
5612 t->vn_next = 0;
5613 else
5614 t->vn_next = (sizeof (Elf_External_Verneed)
5615 + caux * sizeof (Elf_External_Vernaux));
5617 _bfd_elf_swap_verneed_out (output_bfd, t,
5618 (Elf_External_Verneed *) p);
5619 p += sizeof (Elf_External_Verneed);
5621 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5623 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5624 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5625 a->vna_nodename, FALSE);
5626 if (indx == (bfd_size_type) -1)
5627 return FALSE;
5628 a->vna_name = indx;
5629 if (a->vna_nextptr == NULL)
5630 a->vna_next = 0;
5631 else
5632 a->vna_next = sizeof (Elf_External_Vernaux);
5634 _bfd_elf_swap_vernaux_out (output_bfd, a,
5635 (Elf_External_Vernaux *) p);
5636 p += sizeof (Elf_External_Vernaux);
5640 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5641 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5642 return FALSE;
5644 elf_tdata (output_bfd)->cverrefs = crefs;
5648 /* Assign dynsym indicies. In a shared library we generate a
5649 section symbol for each output section, which come first.
5650 Next come all of the back-end allocated local dynamic syms,
5651 followed by the rest of the global symbols. */
5653 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5654 &section_sym_count);
5656 /* Work out the size of the symbol version section. */
5657 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5658 BFD_ASSERT (s != NULL);
5659 if (dynsymcount == 0
5660 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL
5661 && !info->create_default_symver))
5663 _bfd_strip_section_from_output (info, s);
5664 /* The DYNSYMCOUNT might have changed if we were going to
5665 output a dynamic symbol table entry for S. */
5666 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5667 &section_sym_count);
5669 else
5671 s->size = dynsymcount * sizeof (Elf_External_Versym);
5672 s->contents = bfd_zalloc (output_bfd, s->size);
5673 if (s->contents == NULL)
5674 return FALSE;
5676 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5677 return FALSE;
5680 /* Set the size of the .dynsym and .hash sections. We counted
5681 the number of dynamic symbols in elf_link_add_object_symbols.
5682 We will build the contents of .dynsym and .hash when we build
5683 the final symbol table, because until then we do not know the
5684 correct value to give the symbols. We built the .dynstr
5685 section as we went along in elf_link_add_object_symbols. */
5686 s = bfd_get_section_by_name (dynobj, ".dynsym");
5687 BFD_ASSERT (s != NULL);
5688 s->size = dynsymcount * bed->s->sizeof_sym;
5690 if (dynsymcount != 0)
5692 s->contents = bfd_alloc (output_bfd, s->size);
5693 if (s->contents == NULL)
5694 return FALSE;
5696 /* The first entry in .dynsym is a dummy symbol.
5697 Clear all the section syms, in case we don't output them all. */
5698 ++section_sym_count;
5699 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
5702 /* Compute the size of the hashing table. As a side effect this
5703 computes the hash values for all the names we export. */
5704 bucketcount = compute_bucket_count (info);
5706 s = bfd_get_section_by_name (dynobj, ".hash");
5707 BFD_ASSERT (s != NULL);
5708 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5709 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5710 s->contents = bfd_zalloc (output_bfd, s->size);
5711 if (s->contents == NULL)
5712 return FALSE;
5714 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5715 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5716 s->contents + hash_entry_size);
5718 elf_hash_table (info)->bucketcount = bucketcount;
5720 s = bfd_get_section_by_name (dynobj, ".dynstr");
5721 BFD_ASSERT (s != NULL);
5723 elf_finalize_dynstr (output_bfd, info);
5725 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5727 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5728 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5729 return FALSE;
5732 return TRUE;
5735 /* Final phase of ELF linker. */
5737 /* A structure we use to avoid passing large numbers of arguments. */
5739 struct elf_final_link_info
5741 /* General link information. */
5742 struct bfd_link_info *info;
5743 /* Output BFD. */
5744 bfd *output_bfd;
5745 /* Symbol string table. */
5746 struct bfd_strtab_hash *symstrtab;
5747 /* .dynsym section. */
5748 asection *dynsym_sec;
5749 /* .hash section. */
5750 asection *hash_sec;
5751 /* symbol version section (.gnu.version). */
5752 asection *symver_sec;
5753 /* Buffer large enough to hold contents of any section. */
5754 bfd_byte *contents;
5755 /* Buffer large enough to hold external relocs of any section. */
5756 void *external_relocs;
5757 /* Buffer large enough to hold internal relocs of any section. */
5758 Elf_Internal_Rela *internal_relocs;
5759 /* Buffer large enough to hold external local symbols of any input
5760 BFD. */
5761 bfd_byte *external_syms;
5762 /* And a buffer for symbol section indices. */
5763 Elf_External_Sym_Shndx *locsym_shndx;
5764 /* Buffer large enough to hold internal local symbols of any input
5765 BFD. */
5766 Elf_Internal_Sym *internal_syms;
5767 /* Array large enough to hold a symbol index for each local symbol
5768 of any input BFD. */
5769 long *indices;
5770 /* Array large enough to hold a section pointer for each local
5771 symbol of any input BFD. */
5772 asection **sections;
5773 /* Buffer to hold swapped out symbols. */
5774 bfd_byte *symbuf;
5775 /* And one for symbol section indices. */
5776 Elf_External_Sym_Shndx *symshndxbuf;
5777 /* Number of swapped out symbols in buffer. */
5778 size_t symbuf_count;
5779 /* Number of symbols which fit in symbuf. */
5780 size_t symbuf_size;
5781 /* And same for symshndxbuf. */
5782 size_t shndxbuf_size;
5785 /* This struct is used to pass information to elf_link_output_extsym. */
5787 struct elf_outext_info
5789 bfd_boolean failed;
5790 bfd_boolean localsyms;
5791 struct elf_final_link_info *finfo;
5794 /* When performing a relocatable link, the input relocations are
5795 preserved. But, if they reference global symbols, the indices
5796 referenced must be updated. Update all the relocations in
5797 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5799 static void
5800 elf_link_adjust_relocs (bfd *abfd,
5801 Elf_Internal_Shdr *rel_hdr,
5802 unsigned int count,
5803 struct elf_link_hash_entry **rel_hash)
5805 unsigned int i;
5806 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5807 bfd_byte *erela;
5808 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5809 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5810 bfd_vma r_type_mask;
5811 int r_sym_shift;
5813 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5815 swap_in = bed->s->swap_reloc_in;
5816 swap_out = bed->s->swap_reloc_out;
5818 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5820 swap_in = bed->s->swap_reloca_in;
5821 swap_out = bed->s->swap_reloca_out;
5823 else
5824 abort ();
5826 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5827 abort ();
5829 if (bed->s->arch_size == 32)
5831 r_type_mask = 0xff;
5832 r_sym_shift = 8;
5834 else
5836 r_type_mask = 0xffffffff;
5837 r_sym_shift = 32;
5840 erela = rel_hdr->contents;
5841 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5843 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5844 unsigned int j;
5846 if (*rel_hash == NULL)
5847 continue;
5849 BFD_ASSERT ((*rel_hash)->indx >= 0);
5851 (*swap_in) (abfd, erela, irela);
5852 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5853 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5854 | (irela[j].r_info & r_type_mask));
5855 (*swap_out) (abfd, irela, erela);
5859 struct elf_link_sort_rela
5861 union {
5862 bfd_vma offset;
5863 bfd_vma sym_mask;
5864 } u;
5865 enum elf_reloc_type_class type;
5866 /* We use this as an array of size int_rels_per_ext_rel. */
5867 Elf_Internal_Rela rela[1];
5870 static int
5871 elf_link_sort_cmp1 (const void *A, const void *B)
5873 const struct elf_link_sort_rela *a = A;
5874 const struct elf_link_sort_rela *b = B;
5875 int relativea, relativeb;
5877 relativea = a->type == reloc_class_relative;
5878 relativeb = b->type == reloc_class_relative;
5880 if (relativea < relativeb)
5881 return 1;
5882 if (relativea > relativeb)
5883 return -1;
5884 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5885 return -1;
5886 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5887 return 1;
5888 if (a->rela->r_offset < b->rela->r_offset)
5889 return -1;
5890 if (a->rela->r_offset > b->rela->r_offset)
5891 return 1;
5892 return 0;
5895 static int
5896 elf_link_sort_cmp2 (const void *A, const void *B)
5898 const struct elf_link_sort_rela *a = A;
5899 const struct elf_link_sort_rela *b = B;
5900 int copya, copyb;
5902 if (a->u.offset < b->u.offset)
5903 return -1;
5904 if (a->u.offset > b->u.offset)
5905 return 1;
5906 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5907 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5908 if (copya < copyb)
5909 return -1;
5910 if (copya > copyb)
5911 return 1;
5912 if (a->rela->r_offset < b->rela->r_offset)
5913 return -1;
5914 if (a->rela->r_offset > b->rela->r_offset)
5915 return 1;
5916 return 0;
5919 static size_t
5920 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5922 asection *reldyn;
5923 bfd_size_type count, size;
5924 size_t i, ret, sort_elt, ext_size;
5925 bfd_byte *sort, *s_non_relative, *p;
5926 struct elf_link_sort_rela *sq;
5927 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5928 int i2e = bed->s->int_rels_per_ext_rel;
5929 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5930 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5931 struct bfd_link_order *lo;
5932 bfd_vma r_sym_mask;
5934 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5935 if (reldyn == NULL || reldyn->size == 0)
5937 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
5938 if (reldyn == NULL || reldyn->size == 0)
5939 return 0;
5940 ext_size = bed->s->sizeof_rel;
5941 swap_in = bed->s->swap_reloc_in;
5942 swap_out = bed->s->swap_reloc_out;
5944 else
5946 ext_size = bed->s->sizeof_rela;
5947 swap_in = bed->s->swap_reloca_in;
5948 swap_out = bed->s->swap_reloca_out;
5950 count = reldyn->size / ext_size;
5952 size = 0;
5953 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5954 if (lo->type == bfd_indirect_link_order)
5956 asection *o = lo->u.indirect.section;
5957 size += o->size;
5960 if (size != reldyn->size)
5961 return 0;
5963 sort_elt = (sizeof (struct elf_link_sort_rela)
5964 + (i2e - 1) * sizeof (Elf_Internal_Rela));
5965 sort = bfd_zmalloc (sort_elt * count);
5966 if (sort == NULL)
5968 (*info->callbacks->warning)
5969 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
5970 return 0;
5973 if (bed->s->arch_size == 32)
5974 r_sym_mask = ~(bfd_vma) 0xff;
5975 else
5976 r_sym_mask = ~(bfd_vma) 0xffffffff;
5978 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5979 if (lo->type == bfd_indirect_link_order)
5981 bfd_byte *erel, *erelend;
5982 asection *o = lo->u.indirect.section;
5984 if (o->contents == NULL && o->size != 0)
5986 /* This is a reloc section that is being handled as a normal
5987 section. See bfd_section_from_shdr. We can't combine
5988 relocs in this case. */
5989 free (sort);
5990 return 0;
5992 erel = o->contents;
5993 erelend = o->contents + o->size;
5994 p = sort + o->output_offset / ext_size * sort_elt;
5995 while (erel < erelend)
5997 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5998 (*swap_in) (abfd, erel, s->rela);
5999 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
6000 s->u.sym_mask = r_sym_mask;
6001 p += sort_elt;
6002 erel += ext_size;
6006 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
6008 for (i = 0, p = sort; i < count; i++, p += sort_elt)
6010 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6011 if (s->type != reloc_class_relative)
6012 break;
6014 ret = i;
6015 s_non_relative = p;
6017 sq = (struct elf_link_sort_rela *) s_non_relative;
6018 for (; i < count; i++, p += sort_elt)
6020 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
6021 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
6022 sq = sp;
6023 sp->u.offset = sq->rela->r_offset;
6026 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
6028 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
6029 if (lo->type == bfd_indirect_link_order)
6031 bfd_byte *erel, *erelend;
6032 asection *o = lo->u.indirect.section;
6034 erel = o->contents;
6035 erelend = o->contents + o->size;
6036 p = sort + o->output_offset / ext_size * sort_elt;
6037 while (erel < erelend)
6039 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6040 (*swap_out) (abfd, s->rela, erel);
6041 p += sort_elt;
6042 erel += ext_size;
6046 free (sort);
6047 *psec = reldyn;
6048 return ret;
6051 /* Flush the output symbols to the file. */
6053 static bfd_boolean
6054 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
6055 const struct elf_backend_data *bed)
6057 if (finfo->symbuf_count > 0)
6059 Elf_Internal_Shdr *hdr;
6060 file_ptr pos;
6061 bfd_size_type amt;
6063 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6064 pos = hdr->sh_offset + hdr->sh_size;
6065 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6066 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6067 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6068 return FALSE;
6070 hdr->sh_size += amt;
6071 finfo->symbuf_count = 0;
6074 return TRUE;
6077 /* Add a symbol to the output symbol table. */
6079 static bfd_boolean
6080 elf_link_output_sym (struct elf_final_link_info *finfo,
6081 const char *name,
6082 Elf_Internal_Sym *elfsym,
6083 asection *input_sec,
6084 struct elf_link_hash_entry *h)
6086 bfd_byte *dest;
6087 Elf_External_Sym_Shndx *destshndx;
6088 bfd_boolean (*output_symbol_hook)
6089 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6090 struct elf_link_hash_entry *);
6091 const struct elf_backend_data *bed;
6093 bed = get_elf_backend_data (finfo->output_bfd);
6094 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6095 if (output_symbol_hook != NULL)
6097 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6098 return FALSE;
6101 if (name == NULL || *name == '\0')
6102 elfsym->st_name = 0;
6103 else if (input_sec->flags & SEC_EXCLUDE)
6104 elfsym->st_name = 0;
6105 else
6107 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6108 name, TRUE, FALSE);
6109 if (elfsym->st_name == (unsigned long) -1)
6110 return FALSE;
6113 if (finfo->symbuf_count >= finfo->symbuf_size)
6115 if (! elf_link_flush_output_syms (finfo, bed))
6116 return FALSE;
6119 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6120 destshndx = finfo->symshndxbuf;
6121 if (destshndx != NULL)
6123 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6125 bfd_size_type amt;
6127 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6128 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6129 if (destshndx == NULL)
6130 return FALSE;
6131 memset ((char *) destshndx + amt, 0, amt);
6132 finfo->shndxbuf_size *= 2;
6134 destshndx += bfd_get_symcount (finfo->output_bfd);
6137 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6138 finfo->symbuf_count += 1;
6139 bfd_get_symcount (finfo->output_bfd) += 1;
6141 return TRUE;
6144 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6145 allowing an unsatisfied unversioned symbol in the DSO to match a
6146 versioned symbol that would normally require an explicit version.
6147 We also handle the case that a DSO references a hidden symbol
6148 which may be satisfied by a versioned symbol in another DSO. */
6150 static bfd_boolean
6151 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6152 const struct elf_backend_data *bed,
6153 struct elf_link_hash_entry *h)
6155 bfd *abfd;
6156 struct elf_link_loaded_list *loaded;
6158 if (!is_elf_hash_table (info->hash))
6159 return FALSE;
6161 switch (h->root.type)
6163 default:
6164 abfd = NULL;
6165 break;
6167 case bfd_link_hash_undefined:
6168 case bfd_link_hash_undefweak:
6169 abfd = h->root.u.undef.abfd;
6170 if ((abfd->flags & DYNAMIC) == 0
6171 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6172 return FALSE;
6173 break;
6175 case bfd_link_hash_defined:
6176 case bfd_link_hash_defweak:
6177 abfd = h->root.u.def.section->owner;
6178 break;
6180 case bfd_link_hash_common:
6181 abfd = h->root.u.c.p->section->owner;
6182 break;
6184 BFD_ASSERT (abfd != NULL);
6186 for (loaded = elf_hash_table (info)->loaded;
6187 loaded != NULL;
6188 loaded = loaded->next)
6190 bfd *input;
6191 Elf_Internal_Shdr *hdr;
6192 bfd_size_type symcount;
6193 bfd_size_type extsymcount;
6194 bfd_size_type extsymoff;
6195 Elf_Internal_Shdr *versymhdr;
6196 Elf_Internal_Sym *isym;
6197 Elf_Internal_Sym *isymend;
6198 Elf_Internal_Sym *isymbuf;
6199 Elf_External_Versym *ever;
6200 Elf_External_Versym *extversym;
6202 input = loaded->abfd;
6204 /* We check each DSO for a possible hidden versioned definition. */
6205 if (input == abfd
6206 || (input->flags & DYNAMIC) == 0
6207 || elf_dynversym (input) == 0)
6208 continue;
6210 hdr = &elf_tdata (input)->dynsymtab_hdr;
6212 symcount = hdr->sh_size / bed->s->sizeof_sym;
6213 if (elf_bad_symtab (input))
6215 extsymcount = symcount;
6216 extsymoff = 0;
6218 else
6220 extsymcount = symcount - hdr->sh_info;
6221 extsymoff = hdr->sh_info;
6224 if (extsymcount == 0)
6225 continue;
6227 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6228 NULL, NULL, NULL);
6229 if (isymbuf == NULL)
6230 return FALSE;
6232 /* Read in any version definitions. */
6233 versymhdr = &elf_tdata (input)->dynversym_hdr;
6234 extversym = bfd_malloc (versymhdr->sh_size);
6235 if (extversym == NULL)
6236 goto error_ret;
6238 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6239 || (bfd_bread (extversym, versymhdr->sh_size, input)
6240 != versymhdr->sh_size))
6242 free (extversym);
6243 error_ret:
6244 free (isymbuf);
6245 return FALSE;
6248 ever = extversym + extsymoff;
6249 isymend = isymbuf + extsymcount;
6250 for (isym = isymbuf; isym < isymend; isym++, ever++)
6252 const char *name;
6253 Elf_Internal_Versym iver;
6254 unsigned short version_index;
6256 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6257 || isym->st_shndx == SHN_UNDEF)
6258 continue;
6260 name = bfd_elf_string_from_elf_section (input,
6261 hdr->sh_link,
6262 isym->st_name);
6263 if (strcmp (name, h->root.root.string) != 0)
6264 continue;
6266 _bfd_elf_swap_versym_in (input, ever, &iver);
6268 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6270 /* If we have a non-hidden versioned sym, then it should
6271 have provided a definition for the undefined sym. */
6272 abort ();
6275 version_index = iver.vs_vers & VERSYM_VERSION;
6276 if (version_index == 1 || version_index == 2)
6278 /* This is the base or first version. We can use it. */
6279 free (extversym);
6280 free (isymbuf);
6281 return TRUE;
6285 free (extversym);
6286 free (isymbuf);
6289 return FALSE;
6292 /* Add an external symbol to the symbol table. This is called from
6293 the hash table traversal routine. When generating a shared object,
6294 we go through the symbol table twice. The first time we output
6295 anything that might have been forced to local scope in a version
6296 script. The second time we output the symbols that are still
6297 global symbols. */
6299 static bfd_boolean
6300 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6302 struct elf_outext_info *eoinfo = data;
6303 struct elf_final_link_info *finfo = eoinfo->finfo;
6304 bfd_boolean strip;
6305 Elf_Internal_Sym sym;
6306 asection *input_sec;
6307 const struct elf_backend_data *bed;
6309 if (h->root.type == bfd_link_hash_warning)
6311 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6312 if (h->root.type == bfd_link_hash_new)
6313 return TRUE;
6316 /* Decide whether to output this symbol in this pass. */
6317 if (eoinfo->localsyms)
6319 if (!h->forced_local)
6320 return TRUE;
6322 else
6324 if (h->forced_local)
6325 return TRUE;
6328 bed = get_elf_backend_data (finfo->output_bfd);
6330 /* If we have an undefined symbol reference here then it must have
6331 come from a shared library that is being linked in. (Undefined
6332 references in regular files have already been handled). If we
6333 are reporting errors for this situation then do so now. */
6334 if (h->root.type == bfd_link_hash_undefined
6335 && h->ref_dynamic
6336 && !h->ref_regular
6337 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6338 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6340 if (! ((*finfo->info->callbacks->undefined_symbol)
6341 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6342 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6344 eoinfo->failed = TRUE;
6345 return FALSE;
6349 /* We should also warn if a forced local symbol is referenced from
6350 shared libraries. */
6351 if (! finfo->info->relocatable
6352 && (! finfo->info->shared)
6353 && h->forced_local
6354 && h->ref_dynamic
6355 && !h->dynamic_def
6356 && !h->dynamic_weak
6357 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6359 (*_bfd_error_handler)
6360 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6361 finfo->output_bfd, h->root.u.def.section->owner,
6362 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6363 ? "internal"
6364 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6365 ? "hidden" : "local",
6366 h->root.root.string);
6367 eoinfo->failed = TRUE;
6368 return FALSE;
6371 /* We don't want to output symbols that have never been mentioned by
6372 a regular file, or that we have been told to strip. However, if
6373 h->indx is set to -2, the symbol is used by a reloc and we must
6374 output it. */
6375 if (h->indx == -2)
6376 strip = FALSE;
6377 else if ((h->def_dynamic
6378 || h->ref_dynamic
6379 || h->root.type == bfd_link_hash_new)
6380 && !h->def_regular
6381 && !h->ref_regular)
6382 strip = TRUE;
6383 else if (finfo->info->strip == strip_all)
6384 strip = TRUE;
6385 else if (finfo->info->strip == strip_some
6386 && bfd_hash_lookup (finfo->info->keep_hash,
6387 h->root.root.string, FALSE, FALSE) == NULL)
6388 strip = TRUE;
6389 else if (finfo->info->strip_discarded
6390 && (h->root.type == bfd_link_hash_defined
6391 || h->root.type == bfd_link_hash_defweak)
6392 && elf_discarded_section (h->root.u.def.section))
6393 strip = TRUE;
6394 else
6395 strip = FALSE;
6397 /* If we're stripping it, and it's not a dynamic symbol, there's
6398 nothing else to do unless it is a forced local symbol. */
6399 if (strip
6400 && h->dynindx == -1
6401 && !h->forced_local)
6402 return TRUE;
6404 sym.st_value = 0;
6405 sym.st_size = h->size;
6406 sym.st_other = h->other;
6407 if (h->forced_local)
6408 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6409 else if (h->root.type == bfd_link_hash_undefweak
6410 || h->root.type == bfd_link_hash_defweak)
6411 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6412 else
6413 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6415 switch (h->root.type)
6417 default:
6418 case bfd_link_hash_new:
6419 case bfd_link_hash_warning:
6420 abort ();
6421 return FALSE;
6423 case bfd_link_hash_undefined:
6424 case bfd_link_hash_undefweak:
6425 input_sec = bfd_und_section_ptr;
6426 sym.st_shndx = SHN_UNDEF;
6427 break;
6429 case bfd_link_hash_defined:
6430 case bfd_link_hash_defweak:
6432 input_sec = h->root.u.def.section;
6433 if (input_sec->output_section != NULL)
6435 sym.st_shndx =
6436 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6437 input_sec->output_section);
6438 if (sym.st_shndx == SHN_BAD)
6440 (*_bfd_error_handler)
6441 (_("%B: could not find output section %A for input section %A"),
6442 finfo->output_bfd, input_sec->output_section, input_sec);
6443 eoinfo->failed = TRUE;
6444 return FALSE;
6447 /* ELF symbols in relocatable files are section relative,
6448 but in nonrelocatable files they are virtual
6449 addresses. */
6450 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6451 if (! finfo->info->relocatable)
6453 sym.st_value += input_sec->output_section->vma;
6454 if (h->type == STT_TLS)
6456 /* STT_TLS symbols are relative to PT_TLS segment
6457 base. */
6458 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6459 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6463 else
6465 BFD_ASSERT (input_sec->owner == NULL
6466 || (input_sec->owner->flags & DYNAMIC) != 0);
6467 sym.st_shndx = SHN_UNDEF;
6468 input_sec = bfd_und_section_ptr;
6471 break;
6473 case bfd_link_hash_common:
6474 input_sec = h->root.u.c.p->section;
6475 sym.st_shndx = SHN_COMMON;
6476 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6477 break;
6479 case bfd_link_hash_indirect:
6480 /* These symbols are created by symbol versioning. They point
6481 to the decorated version of the name. For example, if the
6482 symbol foo@@GNU_1.2 is the default, which should be used when
6483 foo is used with no version, then we add an indirect symbol
6484 foo which points to foo@@GNU_1.2. We ignore these symbols,
6485 since the indirected symbol is already in the hash table. */
6486 return TRUE;
6489 /* Give the processor backend a chance to tweak the symbol value,
6490 and also to finish up anything that needs to be done for this
6491 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6492 forced local syms when non-shared is due to a historical quirk. */
6493 if ((h->dynindx != -1
6494 || h->forced_local)
6495 && ((finfo->info->shared
6496 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6497 || h->root.type != bfd_link_hash_undefweak))
6498 || !h->forced_local)
6499 && elf_hash_table (finfo->info)->dynamic_sections_created)
6501 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6502 (finfo->output_bfd, finfo->info, h, &sym)))
6504 eoinfo->failed = TRUE;
6505 return FALSE;
6509 /* If we are marking the symbol as undefined, and there are no
6510 non-weak references to this symbol from a regular object, then
6511 mark the symbol as weak undefined; if there are non-weak
6512 references, mark the symbol as strong. We can't do this earlier,
6513 because it might not be marked as undefined until the
6514 finish_dynamic_symbol routine gets through with it. */
6515 if (sym.st_shndx == SHN_UNDEF
6516 && h->ref_regular
6517 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6518 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6520 int bindtype;
6522 if (h->ref_regular_nonweak)
6523 bindtype = STB_GLOBAL;
6524 else
6525 bindtype = STB_WEAK;
6526 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6529 /* If a non-weak symbol with non-default visibility is not defined
6530 locally, it is a fatal error. */
6531 if (! finfo->info->relocatable
6532 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6533 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6534 && h->root.type == bfd_link_hash_undefined
6535 && !h->def_regular)
6537 (*_bfd_error_handler)
6538 (_("%B: %s symbol `%s' isn't defined"),
6539 finfo->output_bfd,
6540 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6541 ? "protected"
6542 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6543 ? "internal" : "hidden",
6544 h->root.root.string);
6545 eoinfo->failed = TRUE;
6546 return FALSE;
6549 /* If this symbol should be put in the .dynsym section, then put it
6550 there now. We already know the symbol index. We also fill in
6551 the entry in the .hash section. */
6552 if (h->dynindx != -1
6553 && elf_hash_table (finfo->info)->dynamic_sections_created)
6555 size_t bucketcount;
6556 size_t bucket;
6557 size_t hash_entry_size;
6558 bfd_byte *bucketpos;
6559 bfd_vma chain;
6560 bfd_byte *esym;
6562 sym.st_name = h->dynstr_index;
6563 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6564 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6566 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6567 bucket = h->u.elf_hash_value % bucketcount;
6568 hash_entry_size
6569 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6570 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6571 + (bucket + 2) * hash_entry_size);
6572 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6573 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6574 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6575 ((bfd_byte *) finfo->hash_sec->contents
6576 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6578 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6580 Elf_Internal_Versym iversym;
6581 Elf_External_Versym *eversym;
6583 if (!h->def_regular)
6585 if (h->verinfo.verdef == NULL)
6586 iversym.vs_vers = 0;
6587 else
6588 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6590 else
6592 if (h->verinfo.vertree == NULL)
6593 iversym.vs_vers = 1;
6594 else
6595 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6596 if (finfo->info->create_default_symver)
6597 iversym.vs_vers++;
6600 if (h->hidden)
6601 iversym.vs_vers |= VERSYM_HIDDEN;
6603 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6604 eversym += h->dynindx;
6605 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6609 /* If we're stripping it, then it was just a dynamic symbol, and
6610 there's nothing else to do. */
6611 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6612 return TRUE;
6614 h->indx = bfd_get_symcount (finfo->output_bfd);
6616 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6618 eoinfo->failed = TRUE;
6619 return FALSE;
6622 return TRUE;
6625 /* Return TRUE if special handling is done for relocs in SEC against
6626 symbols defined in discarded sections. */
6628 static bfd_boolean
6629 elf_section_ignore_discarded_relocs (asection *sec)
6631 const struct elf_backend_data *bed;
6633 switch (sec->sec_info_type)
6635 case ELF_INFO_TYPE_STABS:
6636 case ELF_INFO_TYPE_EH_FRAME:
6637 return TRUE;
6638 default:
6639 break;
6642 bed = get_elf_backend_data (sec->owner);
6643 if (bed->elf_backend_ignore_discarded_relocs != NULL
6644 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6645 return TRUE;
6647 return FALSE;
6650 enum action_discarded
6652 COMPLAIN = 1,
6653 PRETEND = 2
6656 /* Return a mask saying how ld should treat relocations in SEC against
6657 symbols defined in discarded sections. If this function returns
6658 COMPLAIN set, ld will issue a warning message. If this function
6659 returns PRETEND set, and the discarded section was link-once and the
6660 same size as the kept link-once section, ld will pretend that the
6661 symbol was actually defined in the kept section. Otherwise ld will
6662 zero the reloc (at least that is the intent, but some cooperation by
6663 the target dependent code is needed, particularly for REL targets). */
6665 static unsigned int
6666 elf_action_discarded (asection *sec)
6668 if (sec->flags & SEC_DEBUGGING)
6669 return PRETEND;
6671 if (strcmp (".eh_frame", sec->name) == 0)
6672 return 0;
6674 if (strcmp (".gcc_except_table", sec->name) == 0)
6675 return 0;
6677 if (strcmp (".PARISC.unwind", sec->name) == 0)
6678 return 0;
6680 if (strcmp (".fixup", sec->name) == 0)
6681 return 0;
6683 return COMPLAIN | PRETEND;
6686 /* Find a match between a section and a member of a section group. */
6688 static asection *
6689 match_group_member (asection *sec, asection *group)
6691 asection *first = elf_next_in_group (group);
6692 asection *s = first;
6694 while (s != NULL)
6696 if (bfd_elf_match_symbols_in_sections (s, sec))
6697 return s;
6699 if (s == first)
6700 break;
6703 return NULL;
6706 /* Check if the kept section of a discarded section SEC can be used
6707 to replace it. Return the replacement if it is OK. Otherwise return
6708 NULL. */
6710 asection *
6711 _bfd_elf_check_kept_section (asection *sec)
6713 asection *kept;
6715 kept = sec->kept_section;
6716 if (kept != NULL)
6718 if (elf_sec_group (sec) != NULL)
6719 kept = match_group_member (sec, kept);
6720 if (kept != NULL && sec->size != kept->size)
6721 kept = NULL;
6723 return kept;
6726 /* Link an input file into the linker output file. This function
6727 handles all the sections and relocations of the input file at once.
6728 This is so that we only have to read the local symbols once, and
6729 don't have to keep them in memory. */
6731 static bfd_boolean
6732 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6734 bfd_boolean (*relocate_section)
6735 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6736 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6737 bfd *output_bfd;
6738 Elf_Internal_Shdr *symtab_hdr;
6739 size_t locsymcount;
6740 size_t extsymoff;
6741 Elf_Internal_Sym *isymbuf;
6742 Elf_Internal_Sym *isym;
6743 Elf_Internal_Sym *isymend;
6744 long *pindex;
6745 asection **ppsection;
6746 asection *o;
6747 const struct elf_backend_data *bed;
6748 bfd_boolean emit_relocs;
6749 struct elf_link_hash_entry **sym_hashes;
6751 output_bfd = finfo->output_bfd;
6752 bed = get_elf_backend_data (output_bfd);
6753 relocate_section = bed->elf_backend_relocate_section;
6755 /* If this is a dynamic object, we don't want to do anything here:
6756 we don't want the local symbols, and we don't want the section
6757 contents. */
6758 if ((input_bfd->flags & DYNAMIC) != 0)
6759 return TRUE;
6761 emit_relocs = (finfo->info->relocatable
6762 || finfo->info->emitrelocations
6763 || bed->elf_backend_emit_relocs);
6765 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6766 if (elf_bad_symtab (input_bfd))
6768 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6769 extsymoff = 0;
6771 else
6773 locsymcount = symtab_hdr->sh_info;
6774 extsymoff = symtab_hdr->sh_info;
6777 /* Read the local symbols. */
6778 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6779 if (isymbuf == NULL && locsymcount != 0)
6781 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6782 finfo->internal_syms,
6783 finfo->external_syms,
6784 finfo->locsym_shndx);
6785 if (isymbuf == NULL)
6786 return FALSE;
6789 /* Find local symbol sections and adjust values of symbols in
6790 SEC_MERGE sections. Write out those local symbols we know are
6791 going into the output file. */
6792 isymend = isymbuf + locsymcount;
6793 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6794 isym < isymend;
6795 isym++, pindex++, ppsection++)
6797 asection *isec;
6798 const char *name;
6799 Elf_Internal_Sym osym;
6801 *pindex = -1;
6803 if (elf_bad_symtab (input_bfd))
6805 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6807 *ppsection = NULL;
6808 continue;
6812 if (isym->st_shndx == SHN_UNDEF)
6813 isec = bfd_und_section_ptr;
6814 else if (isym->st_shndx < SHN_LORESERVE
6815 || isym->st_shndx > SHN_HIRESERVE)
6817 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6818 if (isec
6819 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6820 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6821 isym->st_value =
6822 _bfd_merged_section_offset (output_bfd, &isec,
6823 elf_section_data (isec)->sec_info,
6824 isym->st_value);
6826 else if (isym->st_shndx == SHN_ABS)
6827 isec = bfd_abs_section_ptr;
6828 else if (isym->st_shndx == SHN_COMMON)
6829 isec = bfd_com_section_ptr;
6830 else
6832 /* Who knows? */
6833 isec = NULL;
6836 *ppsection = isec;
6838 /* Don't output the first, undefined, symbol. */
6839 if (ppsection == finfo->sections)
6840 continue;
6842 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6844 /* We never output section symbols. Instead, we use the
6845 section symbol of the corresponding section in the output
6846 file. */
6847 continue;
6850 /* If we are stripping all symbols, we don't want to output this
6851 one. */
6852 if (finfo->info->strip == strip_all)
6853 continue;
6855 /* If we are discarding all local symbols, we don't want to
6856 output this one. If we are generating a relocatable output
6857 file, then some of the local symbols may be required by
6858 relocs; we output them below as we discover that they are
6859 needed. */
6860 if (finfo->info->discard == discard_all)
6861 continue;
6863 /* If this symbol is defined in a section which we are
6864 discarding, we don't need to keep it, but note that
6865 linker_mark is only reliable for sections that have contents.
6866 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
6867 as well as linker_mark. */
6868 if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6869 && (isec == NULL
6870 || (! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
6871 || (! finfo->info->relocatable
6872 && (isec->flags & SEC_EXCLUDE) != 0)))
6873 continue;
6875 /* If the section is not in the output BFD's section list, it is not
6876 being output. */
6877 if (bfd_section_removed_from_list (output_bfd, isec->output_section))
6878 continue;
6880 /* Get the name of the symbol. */
6881 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6882 isym->st_name);
6883 if (name == NULL)
6884 return FALSE;
6886 /* See if we are discarding symbols with this name. */
6887 if ((finfo->info->strip == strip_some
6888 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6889 == NULL))
6890 || (((finfo->info->discard == discard_sec_merge
6891 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6892 || finfo->info->discard == discard_l)
6893 && bfd_is_local_label_name (input_bfd, name)))
6894 continue;
6896 /* If we get here, we are going to output this symbol. */
6898 osym = *isym;
6900 /* Adjust the section index for the output file. */
6901 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6902 isec->output_section);
6903 if (osym.st_shndx == SHN_BAD)
6904 return FALSE;
6906 *pindex = bfd_get_symcount (output_bfd);
6908 /* ELF symbols in relocatable files are section relative, but
6909 in executable files they are virtual addresses. Note that
6910 this code assumes that all ELF sections have an associated
6911 BFD section with a reasonable value for output_offset; below
6912 we assume that they also have a reasonable value for
6913 output_section. Any special sections must be set up to meet
6914 these requirements. */
6915 osym.st_value += isec->output_offset;
6916 if (! finfo->info->relocatable)
6918 osym.st_value += isec->output_section->vma;
6919 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
6921 /* STT_TLS symbols are relative to PT_TLS segment base. */
6922 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6923 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6927 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
6928 return FALSE;
6931 /* Relocate the contents of each section. */
6932 sym_hashes = elf_sym_hashes (input_bfd);
6933 for (o = input_bfd->sections; o != NULL; o = o->next)
6935 bfd_byte *contents;
6937 if (! o->linker_mark)
6939 /* This section was omitted from the link. */
6940 continue;
6943 if ((o->flags & SEC_HAS_CONTENTS) == 0
6944 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
6945 continue;
6947 if ((o->flags & SEC_LINKER_CREATED) != 0)
6949 /* Section was created by _bfd_elf_link_create_dynamic_sections
6950 or somesuch. */
6951 continue;
6954 /* Get the contents of the section. They have been cached by a
6955 relaxation routine. Note that o is a section in an input
6956 file, so the contents field will not have been set by any of
6957 the routines which work on output files. */
6958 if (elf_section_data (o)->this_hdr.contents != NULL)
6959 contents = elf_section_data (o)->this_hdr.contents;
6960 else
6962 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
6964 contents = finfo->contents;
6965 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
6966 return FALSE;
6969 if ((o->flags & SEC_RELOC) != 0)
6971 Elf_Internal_Rela *internal_relocs;
6972 bfd_vma r_type_mask;
6973 int r_sym_shift;
6975 /* Get the swapped relocs. */
6976 internal_relocs
6977 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
6978 finfo->internal_relocs, FALSE);
6979 if (internal_relocs == NULL
6980 && o->reloc_count > 0)
6981 return FALSE;
6983 if (bed->s->arch_size == 32)
6985 r_type_mask = 0xff;
6986 r_sym_shift = 8;
6988 else
6990 r_type_mask = 0xffffffff;
6991 r_sym_shift = 32;
6994 /* Run through the relocs looking for any against symbols
6995 from discarded sections and section symbols from
6996 removed link-once sections. Complain about relocs
6997 against discarded sections. Zero relocs against removed
6998 link-once sections. Preserve debug information as much
6999 as we can. */
7000 if (!elf_section_ignore_discarded_relocs (o))
7002 Elf_Internal_Rela *rel, *relend;
7003 unsigned int action = elf_action_discarded (o);
7005 rel = internal_relocs;
7006 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
7007 for ( ; rel < relend; rel++)
7009 unsigned long r_symndx = rel->r_info >> r_sym_shift;
7010 asection **ps, *sec;
7011 struct elf_link_hash_entry *h = NULL;
7012 const char *sym_name;
7014 if (r_symndx == STN_UNDEF)
7015 continue;
7017 if (r_symndx >= locsymcount
7018 || (elf_bad_symtab (input_bfd)
7019 && finfo->sections[r_symndx] == NULL))
7021 h = sym_hashes[r_symndx - extsymoff];
7022 while (h->root.type == bfd_link_hash_indirect
7023 || h->root.type == bfd_link_hash_warning)
7024 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7026 if (h->root.type != bfd_link_hash_defined
7027 && h->root.type != bfd_link_hash_defweak)
7028 continue;
7030 ps = &h->root.u.def.section;
7031 sym_name = h->root.root.string;
7033 else
7035 Elf_Internal_Sym *sym = isymbuf + r_symndx;
7036 ps = &finfo->sections[r_symndx];
7037 sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr, sym);
7040 /* Complain if the definition comes from a
7041 discarded section. */
7042 if ((sec = *ps) != NULL && elf_discarded_section (sec))
7044 BFD_ASSERT (r_symndx != 0);
7045 if (action & COMPLAIN)
7047 (*_bfd_error_handler)
7048 (_("`%s' referenced in section `%A' of %B: "
7049 "defined in discarded section `%A' of %B"),
7050 o, input_bfd, sec, sec->owner, sym_name);
7053 /* Try to do the best we can to support buggy old
7054 versions of gcc. If we've warned, or this is
7055 debugging info, pretend that the symbol is
7056 really defined in the kept linkonce section.
7057 FIXME: This is quite broken. Modifying the
7058 symbol here means we will be changing all later
7059 uses of the symbol, not just in this section.
7060 The only thing that makes this half reasonable
7061 is that we warn in non-debug sections, and
7062 debug sections tend to come after other
7063 sections. */
7064 if (action & PRETEND)
7066 asection *kept;
7068 kept = _bfd_elf_check_kept_section (sec);
7069 if (kept != NULL)
7071 *ps = kept;
7072 continue;
7076 /* Remove the symbol reference from the reloc, but
7077 don't kill the reloc completely. This is so that
7078 a zero value will be written into the section,
7079 which may have non-zero contents put there by the
7080 assembler. Zero in things like an eh_frame fde
7081 pc_begin allows stack unwinders to recognize the
7082 fde as bogus. */
7083 rel->r_info &= r_type_mask;
7084 rel->r_addend = 0;
7089 /* Relocate the section by invoking a back end routine.
7091 The back end routine is responsible for adjusting the
7092 section contents as necessary, and (if using Rela relocs
7093 and generating a relocatable output file) adjusting the
7094 reloc addend as necessary.
7096 The back end routine does not have to worry about setting
7097 the reloc address or the reloc symbol index.
7099 The back end routine is given a pointer to the swapped in
7100 internal symbols, and can access the hash table entries
7101 for the external symbols via elf_sym_hashes (input_bfd).
7103 When generating relocatable output, the back end routine
7104 must handle STB_LOCAL/STT_SECTION symbols specially. The
7105 output symbol is going to be a section symbol
7106 corresponding to the output section, which will require
7107 the addend to be adjusted. */
7109 if (! (*relocate_section) (output_bfd, finfo->info,
7110 input_bfd, o, contents,
7111 internal_relocs,
7112 isymbuf,
7113 finfo->sections))
7114 return FALSE;
7116 if (emit_relocs)
7118 Elf_Internal_Rela *irela;
7119 Elf_Internal_Rela *irelaend;
7120 bfd_vma last_offset;
7121 struct elf_link_hash_entry **rel_hash;
7122 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7123 unsigned int next_erel;
7124 bfd_boolean (*reloc_emitter)
7125 (bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *);
7126 bfd_boolean rela_normal;
7128 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7129 rela_normal = (bed->rela_normal
7130 && (input_rel_hdr->sh_entsize
7131 == bed->s->sizeof_rela));
7133 /* Adjust the reloc addresses and symbol indices. */
7135 irela = internal_relocs;
7136 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7137 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7138 + elf_section_data (o->output_section)->rel_count
7139 + elf_section_data (o->output_section)->rel_count2);
7140 last_offset = o->output_offset;
7141 if (!finfo->info->relocatable)
7142 last_offset += o->output_section->vma;
7143 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7145 unsigned long r_symndx;
7146 asection *sec;
7147 Elf_Internal_Sym sym;
7149 if (next_erel == bed->s->int_rels_per_ext_rel)
7151 rel_hash++;
7152 next_erel = 0;
7155 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7156 finfo->info, o,
7157 irela->r_offset);
7158 if (irela->r_offset >= (bfd_vma) -2)
7160 /* This is a reloc for a deleted entry or somesuch.
7161 Turn it into an R_*_NONE reloc, at the same
7162 offset as the last reloc. elf_eh_frame.c and
7163 elf_bfd_discard_info rely on reloc offsets
7164 being ordered. */
7165 irela->r_offset = last_offset;
7166 irela->r_info = 0;
7167 irela->r_addend = 0;
7168 continue;
7171 irela->r_offset += o->output_offset;
7173 /* Relocs in an executable have to be virtual addresses. */
7174 if (!finfo->info->relocatable)
7175 irela->r_offset += o->output_section->vma;
7177 last_offset = irela->r_offset;
7179 r_symndx = irela->r_info >> r_sym_shift;
7180 if (r_symndx == STN_UNDEF)
7181 continue;
7183 if (r_symndx >= locsymcount
7184 || (elf_bad_symtab (input_bfd)
7185 && finfo->sections[r_symndx] == NULL))
7187 struct elf_link_hash_entry *rh;
7188 unsigned long indx;
7190 /* This is a reloc against a global symbol. We
7191 have not yet output all the local symbols, so
7192 we do not know the symbol index of any global
7193 symbol. We set the rel_hash entry for this
7194 reloc to point to the global hash table entry
7195 for this symbol. The symbol index is then
7196 set at the end of bfd_elf_final_link. */
7197 indx = r_symndx - extsymoff;
7198 rh = elf_sym_hashes (input_bfd)[indx];
7199 while (rh->root.type == bfd_link_hash_indirect
7200 || rh->root.type == bfd_link_hash_warning)
7201 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7203 /* Setting the index to -2 tells
7204 elf_link_output_extsym that this symbol is
7205 used by a reloc. */
7206 BFD_ASSERT (rh->indx < 0);
7207 rh->indx = -2;
7209 *rel_hash = rh;
7211 continue;
7214 /* This is a reloc against a local symbol. */
7216 *rel_hash = NULL;
7217 sym = isymbuf[r_symndx];
7218 sec = finfo->sections[r_symndx];
7219 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7221 /* I suppose the backend ought to fill in the
7222 section of any STT_SECTION symbol against a
7223 processor specific section. */
7224 r_symndx = 0;
7225 if (bfd_is_abs_section (sec))
7227 else if (sec == NULL || sec->owner == NULL)
7229 bfd_set_error (bfd_error_bad_value);
7230 return FALSE;
7232 else
7234 asection *osec = sec->output_section;
7236 /* If we have discarded a section, the output
7237 section will be the absolute section. In
7238 case of discarded link-once and discarded
7239 SEC_MERGE sections, use the kept section. */
7240 if (bfd_is_abs_section (osec)
7241 && sec->kept_section != NULL
7242 && sec->kept_section->output_section != NULL)
7244 osec = sec->kept_section->output_section;
7245 irela->r_addend -= osec->vma;
7248 if (!bfd_is_abs_section (osec))
7250 r_symndx = osec->target_index;
7251 BFD_ASSERT (r_symndx != 0);
7255 /* Adjust the addend according to where the
7256 section winds up in the output section. */
7257 if (rela_normal)
7258 irela->r_addend += sec->output_offset;
7260 else
7262 if (finfo->indices[r_symndx] == -1)
7264 unsigned long shlink;
7265 const char *name;
7266 asection *osec;
7268 if (finfo->info->strip == strip_all)
7270 /* You can't do ld -r -s. */
7271 bfd_set_error (bfd_error_invalid_operation);
7272 return FALSE;
7275 /* This symbol was skipped earlier, but
7276 since it is needed by a reloc, we
7277 must output it now. */
7278 shlink = symtab_hdr->sh_link;
7279 name = (bfd_elf_string_from_elf_section
7280 (input_bfd, shlink, sym.st_name));
7281 if (name == NULL)
7282 return FALSE;
7284 osec = sec->output_section;
7285 sym.st_shndx =
7286 _bfd_elf_section_from_bfd_section (output_bfd,
7287 osec);
7288 if (sym.st_shndx == SHN_BAD)
7289 return FALSE;
7291 sym.st_value += sec->output_offset;
7292 if (! finfo->info->relocatable)
7294 sym.st_value += osec->vma;
7295 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7297 /* STT_TLS symbols are relative to PT_TLS
7298 segment base. */
7299 BFD_ASSERT (elf_hash_table (finfo->info)
7300 ->tls_sec != NULL);
7301 sym.st_value -= (elf_hash_table (finfo->info)
7302 ->tls_sec->vma);
7306 finfo->indices[r_symndx]
7307 = bfd_get_symcount (output_bfd);
7309 if (! elf_link_output_sym (finfo, name, &sym, sec,
7310 NULL))
7311 return FALSE;
7314 r_symndx = finfo->indices[r_symndx];
7317 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7318 | (irela->r_info & r_type_mask));
7321 /* Swap out the relocs. */
7322 if (bed->elf_backend_emit_relocs
7323 && !(finfo->info->relocatable
7324 || finfo->info->emitrelocations))
7325 reloc_emitter = bed->elf_backend_emit_relocs;
7326 else
7327 reloc_emitter = _bfd_elf_link_output_relocs;
7329 if (input_rel_hdr->sh_size != 0
7330 && ! (*reloc_emitter) (output_bfd, o, input_rel_hdr,
7331 internal_relocs))
7332 return FALSE;
7334 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7335 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7337 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7338 * bed->s->int_rels_per_ext_rel);
7339 if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2,
7340 internal_relocs))
7341 return FALSE;
7346 /* Write out the modified section contents. */
7347 if (bed->elf_backend_write_section
7348 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7350 /* Section written out. */
7352 else switch (o->sec_info_type)
7354 case ELF_INFO_TYPE_STABS:
7355 if (! (_bfd_write_section_stabs
7356 (output_bfd,
7357 &elf_hash_table (finfo->info)->stab_info,
7358 o, &elf_section_data (o)->sec_info, contents)))
7359 return FALSE;
7360 break;
7361 case ELF_INFO_TYPE_MERGE:
7362 if (! _bfd_write_merged_section (output_bfd, o,
7363 elf_section_data (o)->sec_info))
7364 return FALSE;
7365 break;
7366 case ELF_INFO_TYPE_EH_FRAME:
7368 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7369 o, contents))
7370 return FALSE;
7372 break;
7373 default:
7375 if (! (o->flags & SEC_EXCLUDE)
7376 && ! bfd_set_section_contents (output_bfd, o->output_section,
7377 contents,
7378 (file_ptr) o->output_offset,
7379 o->size))
7380 return FALSE;
7382 break;
7386 return TRUE;
7389 /* Generate a reloc when linking an ELF file. This is a reloc
7390 requested by the linker, and does come from any input file. This
7391 is used to build constructor and destructor tables when linking
7392 with -Ur. */
7394 static bfd_boolean
7395 elf_reloc_link_order (bfd *output_bfd,
7396 struct bfd_link_info *info,
7397 asection *output_section,
7398 struct bfd_link_order *link_order)
7400 reloc_howto_type *howto;
7401 long indx;
7402 bfd_vma offset;
7403 bfd_vma addend;
7404 struct elf_link_hash_entry **rel_hash_ptr;
7405 Elf_Internal_Shdr *rel_hdr;
7406 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7407 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7408 bfd_byte *erel;
7409 unsigned int i;
7411 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7412 if (howto == NULL)
7414 bfd_set_error (bfd_error_bad_value);
7415 return FALSE;
7418 addend = link_order->u.reloc.p->addend;
7420 /* Figure out the symbol index. */
7421 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7422 + elf_section_data (output_section)->rel_count
7423 + elf_section_data (output_section)->rel_count2);
7424 if (link_order->type == bfd_section_reloc_link_order)
7426 indx = link_order->u.reloc.p->u.section->target_index;
7427 BFD_ASSERT (indx != 0);
7428 *rel_hash_ptr = NULL;
7430 else
7432 struct elf_link_hash_entry *h;
7434 /* Treat a reloc against a defined symbol as though it were
7435 actually against the section. */
7436 h = ((struct elf_link_hash_entry *)
7437 bfd_wrapped_link_hash_lookup (output_bfd, info,
7438 link_order->u.reloc.p->u.name,
7439 FALSE, FALSE, TRUE));
7440 if (h != NULL
7441 && (h->root.type == bfd_link_hash_defined
7442 || h->root.type == bfd_link_hash_defweak))
7444 asection *section;
7446 section = h->root.u.def.section;
7447 indx = section->output_section->target_index;
7448 *rel_hash_ptr = NULL;
7449 /* It seems that we ought to add the symbol value to the
7450 addend here, but in practice it has already been added
7451 because it was passed to constructor_callback. */
7452 addend += section->output_section->vma + section->output_offset;
7454 else if (h != NULL)
7456 /* Setting the index to -2 tells elf_link_output_extsym that
7457 this symbol is used by a reloc. */
7458 h->indx = -2;
7459 *rel_hash_ptr = h;
7460 indx = 0;
7462 else
7464 if (! ((*info->callbacks->unattached_reloc)
7465 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7466 return FALSE;
7467 indx = 0;
7471 /* If this is an inplace reloc, we must write the addend into the
7472 object file. */
7473 if (howto->partial_inplace && addend != 0)
7475 bfd_size_type size;
7476 bfd_reloc_status_type rstat;
7477 bfd_byte *buf;
7478 bfd_boolean ok;
7479 const char *sym_name;
7481 size = bfd_get_reloc_size (howto);
7482 buf = bfd_zmalloc (size);
7483 if (buf == NULL)
7484 return FALSE;
7485 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7486 switch (rstat)
7488 case bfd_reloc_ok:
7489 break;
7491 default:
7492 case bfd_reloc_outofrange:
7493 abort ();
7495 case bfd_reloc_overflow:
7496 if (link_order->type == bfd_section_reloc_link_order)
7497 sym_name = bfd_section_name (output_bfd,
7498 link_order->u.reloc.p->u.section);
7499 else
7500 sym_name = link_order->u.reloc.p->u.name;
7501 if (! ((*info->callbacks->reloc_overflow)
7502 (info, NULL, sym_name, howto->name, addend, NULL,
7503 NULL, (bfd_vma) 0)))
7505 free (buf);
7506 return FALSE;
7508 break;
7510 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7511 link_order->offset, size);
7512 free (buf);
7513 if (! ok)
7514 return FALSE;
7517 /* The address of a reloc is relative to the section in a
7518 relocatable file, and is a virtual address in an executable
7519 file. */
7520 offset = link_order->offset;
7521 if (! info->relocatable)
7522 offset += output_section->vma;
7524 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7526 irel[i].r_offset = offset;
7527 irel[i].r_info = 0;
7528 irel[i].r_addend = 0;
7530 if (bed->s->arch_size == 32)
7531 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7532 else
7533 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7535 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7536 erel = rel_hdr->contents;
7537 if (rel_hdr->sh_type == SHT_REL)
7539 erel += (elf_section_data (output_section)->rel_count
7540 * bed->s->sizeof_rel);
7541 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7543 else
7545 irel[0].r_addend = addend;
7546 erel += (elf_section_data (output_section)->rel_count
7547 * bed->s->sizeof_rela);
7548 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7551 ++elf_section_data (output_section)->rel_count;
7553 return TRUE;
7557 /* Get the output vma of the section pointed to by the sh_link field. */
7559 static bfd_vma
7560 elf_get_linked_section_vma (struct bfd_link_order *p)
7562 Elf_Internal_Shdr **elf_shdrp;
7563 asection *s;
7564 int elfsec;
7566 s = p->u.indirect.section;
7567 elf_shdrp = elf_elfsections (s->owner);
7568 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7569 elfsec = elf_shdrp[elfsec]->sh_link;
7570 /* PR 290:
7571 The Intel C compiler generates SHT_IA_64_UNWIND with
7572 SHF_LINK_ORDER. But it doesn't set theh sh_link or
7573 sh_info fields. Hence we could get the situation
7574 where elfsec is 0. */
7575 if (elfsec == 0)
7577 const struct elf_backend_data *bed
7578 = get_elf_backend_data (s->owner);
7579 if (bed->link_order_error_handler)
7580 bed->link_order_error_handler
7581 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
7582 return 0;
7584 else
7586 s = elf_shdrp[elfsec]->bfd_section;
7587 return s->output_section->vma + s->output_offset;
7592 /* Compare two sections based on the locations of the sections they are
7593 linked to. Used by elf_fixup_link_order. */
7595 static int
7596 compare_link_order (const void * a, const void * b)
7598 bfd_vma apos;
7599 bfd_vma bpos;
7601 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7602 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7603 if (apos < bpos)
7604 return -1;
7605 return apos > bpos;
7609 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7610 order as their linked sections. Returns false if this could not be done
7611 because an output section includes both ordered and unordered
7612 sections. Ideally we'd do this in the linker proper. */
7614 static bfd_boolean
7615 elf_fixup_link_order (bfd *abfd, asection *o)
7617 int seen_linkorder;
7618 int seen_other;
7619 int n;
7620 struct bfd_link_order *p;
7621 bfd *sub;
7622 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7623 int elfsec;
7624 struct bfd_link_order **sections;
7625 asection *s;
7626 bfd_vma offset;
7628 seen_other = 0;
7629 seen_linkorder = 0;
7630 for (p = o->link_order_head; p != NULL; p = p->next)
7632 if (p->type == bfd_indirect_link_order
7633 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7634 == bfd_target_elf_flavour)
7635 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7637 s = p->u.indirect.section;
7638 elfsec = _bfd_elf_section_from_bfd_section (sub, s);
7639 if (elfsec != -1
7640 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7641 seen_linkorder++;
7642 else
7643 seen_other++;
7645 else
7646 seen_other++;
7649 if (!seen_linkorder)
7650 return TRUE;
7652 if (seen_other && seen_linkorder)
7654 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
7656 bfd_set_error (bfd_error_bad_value);
7657 return FALSE;
7660 sections = (struct bfd_link_order **)
7661 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7662 seen_linkorder = 0;
7664 for (p = o->link_order_head; p != NULL; p = p->next)
7666 sections[seen_linkorder++] = p;
7668 /* Sort the input sections in the order of their linked section. */
7669 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7670 compare_link_order);
7672 /* Change the offsets of the sections. */
7673 offset = 0;
7674 for (n = 0; n < seen_linkorder; n++)
7676 s = sections[n]->u.indirect.section;
7677 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7678 s->output_offset = offset;
7679 sections[n]->offset = offset;
7680 offset += sections[n]->size;
7683 return TRUE;
7687 /* Do the final step of an ELF link. */
7689 bfd_boolean
7690 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7692 bfd_boolean dynamic;
7693 bfd_boolean emit_relocs;
7694 bfd *dynobj;
7695 struct elf_final_link_info finfo;
7696 register asection *o;
7697 register struct bfd_link_order *p;
7698 register bfd *sub;
7699 bfd_size_type max_contents_size;
7700 bfd_size_type max_external_reloc_size;
7701 bfd_size_type max_internal_reloc_count;
7702 bfd_size_type max_sym_count;
7703 bfd_size_type max_sym_shndx_count;
7704 file_ptr off;
7705 Elf_Internal_Sym elfsym;
7706 unsigned int i;
7707 Elf_Internal_Shdr *symtab_hdr;
7708 Elf_Internal_Shdr *symtab_shndx_hdr;
7709 Elf_Internal_Shdr *symstrtab_hdr;
7710 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7711 struct elf_outext_info eoinfo;
7712 bfd_boolean merged;
7713 size_t relativecount = 0;
7714 asection *reldyn = 0;
7715 bfd_size_type amt;
7717 if (! is_elf_hash_table (info->hash))
7718 return FALSE;
7720 if (info->shared)
7721 abfd->flags |= DYNAMIC;
7723 dynamic = elf_hash_table (info)->dynamic_sections_created;
7724 dynobj = elf_hash_table (info)->dynobj;
7726 emit_relocs = (info->relocatable
7727 || info->emitrelocations
7728 || bed->elf_backend_emit_relocs);
7730 finfo.info = info;
7731 finfo.output_bfd = abfd;
7732 finfo.symstrtab = _bfd_elf_stringtab_init ();
7733 if (finfo.symstrtab == NULL)
7734 return FALSE;
7736 if (! dynamic)
7738 finfo.dynsym_sec = NULL;
7739 finfo.hash_sec = NULL;
7740 finfo.symver_sec = NULL;
7742 else
7744 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7745 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7746 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7747 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7748 /* Note that it is OK if symver_sec is NULL. */
7751 finfo.contents = NULL;
7752 finfo.external_relocs = NULL;
7753 finfo.internal_relocs = NULL;
7754 finfo.external_syms = NULL;
7755 finfo.locsym_shndx = NULL;
7756 finfo.internal_syms = NULL;
7757 finfo.indices = NULL;
7758 finfo.sections = NULL;
7759 finfo.symbuf = NULL;
7760 finfo.symshndxbuf = NULL;
7761 finfo.symbuf_count = 0;
7762 finfo.shndxbuf_size = 0;
7764 /* Count up the number of relocations we will output for each output
7765 section, so that we know the sizes of the reloc sections. We
7766 also figure out some maximum sizes. */
7767 max_contents_size = 0;
7768 max_external_reloc_size = 0;
7769 max_internal_reloc_count = 0;
7770 max_sym_count = 0;
7771 max_sym_shndx_count = 0;
7772 merged = FALSE;
7773 for (o = abfd->sections; o != NULL; o = o->next)
7775 struct bfd_elf_section_data *esdo = elf_section_data (o);
7776 o->reloc_count = 0;
7778 for (p = o->link_order_head; p != NULL; p = p->next)
7780 unsigned int reloc_count = 0;
7781 struct bfd_elf_section_data *esdi = NULL;
7782 unsigned int *rel_count1;
7784 if (p->type == bfd_section_reloc_link_order
7785 || p->type == bfd_symbol_reloc_link_order)
7786 reloc_count = 1;
7787 else if (p->type == bfd_indirect_link_order)
7789 asection *sec;
7791 sec = p->u.indirect.section;
7792 esdi = elf_section_data (sec);
7794 /* Mark all sections which are to be included in the
7795 link. This will normally be every section. We need
7796 to do this so that we can identify any sections which
7797 the linker has decided to not include. */
7798 sec->linker_mark = TRUE;
7800 if (sec->flags & SEC_MERGE)
7801 merged = TRUE;
7803 if (info->relocatable || info->emitrelocations)
7804 reloc_count = sec->reloc_count;
7805 else if (bed->elf_backend_count_relocs)
7807 Elf_Internal_Rela * relocs;
7809 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7810 info->keep_memory);
7812 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7814 if (elf_section_data (o)->relocs != relocs)
7815 free (relocs);
7818 if (sec->rawsize > max_contents_size)
7819 max_contents_size = sec->rawsize;
7820 if (sec->size > max_contents_size)
7821 max_contents_size = sec->size;
7823 /* We are interested in just local symbols, not all
7824 symbols. */
7825 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7826 && (sec->owner->flags & DYNAMIC) == 0)
7828 size_t sym_count;
7830 if (elf_bad_symtab (sec->owner))
7831 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7832 / bed->s->sizeof_sym);
7833 else
7834 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7836 if (sym_count > max_sym_count)
7837 max_sym_count = sym_count;
7839 if (sym_count > max_sym_shndx_count
7840 && elf_symtab_shndx (sec->owner) != 0)
7841 max_sym_shndx_count = sym_count;
7843 if ((sec->flags & SEC_RELOC) != 0)
7845 size_t ext_size;
7847 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7848 if (ext_size > max_external_reloc_size)
7849 max_external_reloc_size = ext_size;
7850 if (sec->reloc_count > max_internal_reloc_count)
7851 max_internal_reloc_count = sec->reloc_count;
7856 if (reloc_count == 0)
7857 continue;
7859 o->reloc_count += reloc_count;
7861 /* MIPS may have a mix of REL and RELA relocs on sections.
7862 To support this curious ABI we keep reloc counts in
7863 elf_section_data too. We must be careful to add the
7864 relocations from the input section to the right output
7865 count. FIXME: Get rid of one count. We have
7866 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7867 rel_count1 = &esdo->rel_count;
7868 if (esdi != NULL)
7870 bfd_boolean same_size;
7871 bfd_size_type entsize1;
7873 entsize1 = esdi->rel_hdr.sh_entsize;
7874 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7875 || entsize1 == bed->s->sizeof_rela);
7876 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7878 if (!same_size)
7879 rel_count1 = &esdo->rel_count2;
7881 if (esdi->rel_hdr2 != NULL)
7883 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7884 unsigned int alt_count;
7885 unsigned int *rel_count2;
7887 BFD_ASSERT (entsize2 != entsize1
7888 && (entsize2 == bed->s->sizeof_rel
7889 || entsize2 == bed->s->sizeof_rela));
7891 rel_count2 = &esdo->rel_count2;
7892 if (!same_size)
7893 rel_count2 = &esdo->rel_count;
7895 /* The following is probably too simplistic if the
7896 backend counts output relocs unusually. */
7897 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7898 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
7899 *rel_count2 += alt_count;
7900 reloc_count -= alt_count;
7903 *rel_count1 += reloc_count;
7906 if (o->reloc_count > 0)
7907 o->flags |= SEC_RELOC;
7908 else
7910 /* Explicitly clear the SEC_RELOC flag. The linker tends to
7911 set it (this is probably a bug) and if it is set
7912 assign_section_numbers will create a reloc section. */
7913 o->flags &=~ SEC_RELOC;
7916 /* If the SEC_ALLOC flag is not set, force the section VMA to
7917 zero. This is done in elf_fake_sections as well, but forcing
7918 the VMA to 0 here will ensure that relocs against these
7919 sections are handled correctly. */
7920 if ((o->flags & SEC_ALLOC) == 0
7921 && ! o->user_set_vma)
7922 o->vma = 0;
7925 if (! info->relocatable && merged)
7926 elf_link_hash_traverse (elf_hash_table (info),
7927 _bfd_elf_link_sec_merge_syms, abfd);
7929 /* Figure out the file positions for everything but the symbol table
7930 and the relocs. We set symcount to force assign_section_numbers
7931 to create a symbol table. */
7932 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
7933 BFD_ASSERT (! abfd->output_has_begun);
7934 if (! _bfd_elf_compute_section_file_positions (abfd, info))
7935 goto error_return;
7937 /* Set sizes, and assign file positions for reloc sections. */
7938 for (o = abfd->sections; o != NULL; o = o->next)
7940 if ((o->flags & SEC_RELOC) != 0)
7942 if (!(_bfd_elf_link_size_reloc_section
7943 (abfd, &elf_section_data (o)->rel_hdr, o)))
7944 goto error_return;
7946 if (elf_section_data (o)->rel_hdr2
7947 && !(_bfd_elf_link_size_reloc_section
7948 (abfd, elf_section_data (o)->rel_hdr2, o)))
7949 goto error_return;
7952 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
7953 to count upwards while actually outputting the relocations. */
7954 elf_section_data (o)->rel_count = 0;
7955 elf_section_data (o)->rel_count2 = 0;
7958 _bfd_elf_assign_file_positions_for_relocs (abfd);
7960 /* We have now assigned file positions for all the sections except
7961 .symtab and .strtab. We start the .symtab section at the current
7962 file position, and write directly to it. We build the .strtab
7963 section in memory. */
7964 bfd_get_symcount (abfd) = 0;
7965 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
7966 /* sh_name is set in prep_headers. */
7967 symtab_hdr->sh_type = SHT_SYMTAB;
7968 /* sh_flags, sh_addr and sh_size all start off zero. */
7969 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
7970 /* sh_link is set in assign_section_numbers. */
7971 /* sh_info is set below. */
7972 /* sh_offset is set just below. */
7973 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
7975 off = elf_tdata (abfd)->next_file_pos;
7976 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
7978 /* Note that at this point elf_tdata (abfd)->next_file_pos is
7979 incorrect. We do not yet know the size of the .symtab section.
7980 We correct next_file_pos below, after we do know the size. */
7982 /* Allocate a buffer to hold swapped out symbols. This is to avoid
7983 continuously seeking to the right position in the file. */
7984 if (! info->keep_memory || max_sym_count < 20)
7985 finfo.symbuf_size = 20;
7986 else
7987 finfo.symbuf_size = max_sym_count;
7988 amt = finfo.symbuf_size;
7989 amt *= bed->s->sizeof_sym;
7990 finfo.symbuf = bfd_malloc (amt);
7991 if (finfo.symbuf == NULL)
7992 goto error_return;
7993 if (elf_numsections (abfd) > SHN_LORESERVE)
7995 /* Wild guess at number of output symbols. realloc'd as needed. */
7996 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
7997 finfo.shndxbuf_size = amt;
7998 amt *= sizeof (Elf_External_Sym_Shndx);
7999 finfo.symshndxbuf = bfd_zmalloc (amt);
8000 if (finfo.symshndxbuf == NULL)
8001 goto error_return;
8004 /* Start writing out the symbol table. The first symbol is always a
8005 dummy symbol. */
8006 if (info->strip != strip_all
8007 || emit_relocs)
8009 elfsym.st_value = 0;
8010 elfsym.st_size = 0;
8011 elfsym.st_info = 0;
8012 elfsym.st_other = 0;
8013 elfsym.st_shndx = SHN_UNDEF;
8014 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
8015 NULL))
8016 goto error_return;
8019 /* Output a symbol for each section. We output these even if we are
8020 discarding local symbols, since they are used for relocs. These
8021 symbols have no names. We store the index of each one in the
8022 index field of the section, so that we can find it again when
8023 outputting relocs. */
8024 if (info->strip != strip_all
8025 || emit_relocs)
8027 elfsym.st_size = 0;
8028 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8029 elfsym.st_other = 0;
8030 for (i = 1; i < elf_numsections (abfd); i++)
8032 o = bfd_section_from_elf_index (abfd, i);
8033 if (o != NULL)
8034 o->target_index = bfd_get_symcount (abfd);
8035 elfsym.st_shndx = i;
8036 if (info->relocatable || o == NULL)
8037 elfsym.st_value = 0;
8038 else
8039 elfsym.st_value = o->vma;
8040 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
8041 goto error_return;
8042 if (i == SHN_LORESERVE - 1)
8043 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
8047 /* Allocate some memory to hold information read in from the input
8048 files. */
8049 if (max_contents_size != 0)
8051 finfo.contents = bfd_malloc (max_contents_size);
8052 if (finfo.contents == NULL)
8053 goto error_return;
8056 if (max_external_reloc_size != 0)
8058 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
8059 if (finfo.external_relocs == NULL)
8060 goto error_return;
8063 if (max_internal_reloc_count != 0)
8065 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
8066 amt *= sizeof (Elf_Internal_Rela);
8067 finfo.internal_relocs = bfd_malloc (amt);
8068 if (finfo.internal_relocs == NULL)
8069 goto error_return;
8072 if (max_sym_count != 0)
8074 amt = max_sym_count * bed->s->sizeof_sym;
8075 finfo.external_syms = bfd_malloc (amt);
8076 if (finfo.external_syms == NULL)
8077 goto error_return;
8079 amt = max_sym_count * sizeof (Elf_Internal_Sym);
8080 finfo.internal_syms = bfd_malloc (amt);
8081 if (finfo.internal_syms == NULL)
8082 goto error_return;
8084 amt = max_sym_count * sizeof (long);
8085 finfo.indices = bfd_malloc (amt);
8086 if (finfo.indices == NULL)
8087 goto error_return;
8089 amt = max_sym_count * sizeof (asection *);
8090 finfo.sections = bfd_malloc (amt);
8091 if (finfo.sections == NULL)
8092 goto error_return;
8095 if (max_sym_shndx_count != 0)
8097 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8098 finfo.locsym_shndx = bfd_malloc (amt);
8099 if (finfo.locsym_shndx == NULL)
8100 goto error_return;
8103 if (elf_hash_table (info)->tls_sec)
8105 bfd_vma base, end = 0;
8106 asection *sec;
8108 for (sec = elf_hash_table (info)->tls_sec;
8109 sec && (sec->flags & SEC_THREAD_LOCAL);
8110 sec = sec->next)
8112 bfd_vma size = sec->size;
8114 if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8116 struct bfd_link_order *o;
8118 for (o = sec->link_order_head; o != NULL; o = o->next)
8119 if (size < o->offset + o->size)
8120 size = o->offset + o->size;
8122 end = sec->vma + size;
8124 base = elf_hash_table (info)->tls_sec->vma;
8125 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8126 elf_hash_table (info)->tls_size = end - base;
8129 /* Reorder SHF_LINK_ORDER sections. */
8130 for (o = abfd->sections; o != NULL; o = o->next)
8132 if (!elf_fixup_link_order (abfd, o))
8133 return FALSE;
8136 /* Since ELF permits relocations to be against local symbols, we
8137 must have the local symbols available when we do the relocations.
8138 Since we would rather only read the local symbols once, and we
8139 would rather not keep them in memory, we handle all the
8140 relocations for a single input file at the same time.
8142 Unfortunately, there is no way to know the total number of local
8143 symbols until we have seen all of them, and the local symbol
8144 indices precede the global symbol indices. This means that when
8145 we are generating relocatable output, and we see a reloc against
8146 a global symbol, we can not know the symbol index until we have
8147 finished examining all the local symbols to see which ones we are
8148 going to output. To deal with this, we keep the relocations in
8149 memory, and don't output them until the end of the link. This is
8150 an unfortunate waste of memory, but I don't see a good way around
8151 it. Fortunately, it only happens when performing a relocatable
8152 link, which is not the common case. FIXME: If keep_memory is set
8153 we could write the relocs out and then read them again; I don't
8154 know how bad the memory loss will be. */
8156 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8157 sub->output_has_begun = FALSE;
8158 for (o = abfd->sections; o != NULL; o = o->next)
8160 for (p = o->link_order_head; p != NULL; p = p->next)
8162 if (p->type == bfd_indirect_link_order
8163 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8164 == bfd_target_elf_flavour)
8165 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8167 if (! sub->output_has_begun)
8169 if (! elf_link_input_bfd (&finfo, sub))
8170 goto error_return;
8171 sub->output_has_begun = TRUE;
8174 else if (p->type == bfd_section_reloc_link_order
8175 || p->type == bfd_symbol_reloc_link_order)
8177 if (! elf_reloc_link_order (abfd, info, o, p))
8178 goto error_return;
8180 else
8182 if (! _bfd_default_link_order (abfd, info, o, p))
8183 goto error_return;
8188 /* Output any global symbols that got converted to local in a
8189 version script or due to symbol visibility. We do this in a
8190 separate step since ELF requires all local symbols to appear
8191 prior to any global symbols. FIXME: We should only do this if
8192 some global symbols were, in fact, converted to become local.
8193 FIXME: Will this work correctly with the Irix 5 linker? */
8194 eoinfo.failed = FALSE;
8195 eoinfo.finfo = &finfo;
8196 eoinfo.localsyms = TRUE;
8197 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8198 &eoinfo);
8199 if (eoinfo.failed)
8200 return FALSE;
8202 /* That wrote out all the local symbols. Finish up the symbol table
8203 with the global symbols. Even if we want to strip everything we
8204 can, we still need to deal with those global symbols that got
8205 converted to local in a version script. */
8207 /* The sh_info field records the index of the first non local symbol. */
8208 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8210 if (dynamic
8211 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8213 Elf_Internal_Sym sym;
8214 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8215 long last_local = 0;
8217 /* Write out the section symbols for the output sections. */
8218 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
8220 asection *s;
8222 sym.st_size = 0;
8223 sym.st_name = 0;
8224 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8225 sym.st_other = 0;
8227 for (s = abfd->sections; s != NULL; s = s->next)
8229 int indx;
8230 bfd_byte *dest;
8231 long dynindx;
8233 dynindx = elf_section_data (s)->dynindx;
8234 if (dynindx <= 0)
8235 continue;
8236 indx = elf_section_data (s)->this_idx;
8237 BFD_ASSERT (indx > 0);
8238 sym.st_shndx = indx;
8239 sym.st_value = s->vma;
8240 dest = dynsym + dynindx * bed->s->sizeof_sym;
8241 if (last_local < dynindx)
8242 last_local = dynindx;
8243 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8247 /* Write out the local dynsyms. */
8248 if (elf_hash_table (info)->dynlocal)
8250 struct elf_link_local_dynamic_entry *e;
8251 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8253 asection *s;
8254 bfd_byte *dest;
8256 sym.st_size = e->isym.st_size;
8257 sym.st_other = e->isym.st_other;
8259 /* Copy the internal symbol as is.
8260 Note that we saved a word of storage and overwrote
8261 the original st_name with the dynstr_index. */
8262 sym = e->isym;
8264 if (e->isym.st_shndx != SHN_UNDEF
8265 && (e->isym.st_shndx < SHN_LORESERVE
8266 || e->isym.st_shndx > SHN_HIRESERVE))
8268 s = bfd_section_from_elf_index (e->input_bfd,
8269 e->isym.st_shndx);
8271 sym.st_shndx =
8272 elf_section_data (s->output_section)->this_idx;
8273 sym.st_value = (s->output_section->vma
8274 + s->output_offset
8275 + e->isym.st_value);
8278 if (last_local < e->dynindx)
8279 last_local = e->dynindx;
8281 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8282 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8286 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8287 last_local + 1;
8290 /* We get the global symbols from the hash table. */
8291 eoinfo.failed = FALSE;
8292 eoinfo.localsyms = FALSE;
8293 eoinfo.finfo = &finfo;
8294 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8295 &eoinfo);
8296 if (eoinfo.failed)
8297 return FALSE;
8299 /* If backend needs to output some symbols not present in the hash
8300 table, do it now. */
8301 if (bed->elf_backend_output_arch_syms)
8303 typedef bfd_boolean (*out_sym_func)
8304 (void *, const char *, Elf_Internal_Sym *, asection *,
8305 struct elf_link_hash_entry *);
8307 if (! ((*bed->elf_backend_output_arch_syms)
8308 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8309 return FALSE;
8312 /* Flush all symbols to the file. */
8313 if (! elf_link_flush_output_syms (&finfo, bed))
8314 return FALSE;
8316 /* Now we know the size of the symtab section. */
8317 off += symtab_hdr->sh_size;
8319 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8320 if (symtab_shndx_hdr->sh_name != 0)
8322 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8323 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8324 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8325 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8326 symtab_shndx_hdr->sh_size = amt;
8328 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8329 off, TRUE);
8331 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8332 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8333 return FALSE;
8337 /* Finish up and write out the symbol string table (.strtab)
8338 section. */
8339 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8340 /* sh_name was set in prep_headers. */
8341 symstrtab_hdr->sh_type = SHT_STRTAB;
8342 symstrtab_hdr->sh_flags = 0;
8343 symstrtab_hdr->sh_addr = 0;
8344 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8345 symstrtab_hdr->sh_entsize = 0;
8346 symstrtab_hdr->sh_link = 0;
8347 symstrtab_hdr->sh_info = 0;
8348 /* sh_offset is set just below. */
8349 symstrtab_hdr->sh_addralign = 1;
8351 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8352 elf_tdata (abfd)->next_file_pos = off;
8354 if (bfd_get_symcount (abfd) > 0)
8356 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8357 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8358 return FALSE;
8361 /* Adjust the relocs to have the correct symbol indices. */
8362 for (o = abfd->sections; o != NULL; o = o->next)
8364 if ((o->flags & SEC_RELOC) == 0)
8365 continue;
8367 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8368 elf_section_data (o)->rel_count,
8369 elf_section_data (o)->rel_hashes);
8370 if (elf_section_data (o)->rel_hdr2 != NULL)
8371 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8372 elf_section_data (o)->rel_count2,
8373 (elf_section_data (o)->rel_hashes
8374 + elf_section_data (o)->rel_count));
8376 /* Set the reloc_count field to 0 to prevent write_relocs from
8377 trying to swap the relocs out itself. */
8378 o->reloc_count = 0;
8381 if (dynamic && info->combreloc && dynobj != NULL)
8382 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8384 /* If we are linking against a dynamic object, or generating a
8385 shared library, finish up the dynamic linking information. */
8386 if (dynamic)
8388 bfd_byte *dyncon, *dynconend;
8390 /* Fix up .dynamic entries. */
8391 o = bfd_get_section_by_name (dynobj, ".dynamic");
8392 BFD_ASSERT (o != NULL);
8394 dyncon = o->contents;
8395 dynconend = o->contents + o->size;
8396 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8398 Elf_Internal_Dyn dyn;
8399 const char *name;
8400 unsigned int type;
8402 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8404 switch (dyn.d_tag)
8406 default:
8407 continue;
8408 case DT_NULL:
8409 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8411 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8413 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8414 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8415 default: continue;
8417 dyn.d_un.d_val = relativecount;
8418 relativecount = 0;
8419 break;
8421 continue;
8423 case DT_INIT:
8424 name = info->init_function;
8425 goto get_sym;
8426 case DT_FINI:
8427 name = info->fini_function;
8428 get_sym:
8430 struct elf_link_hash_entry *h;
8432 h = elf_link_hash_lookup (elf_hash_table (info), name,
8433 FALSE, FALSE, TRUE);
8434 if (h != NULL
8435 && (h->root.type == bfd_link_hash_defined
8436 || h->root.type == bfd_link_hash_defweak))
8438 dyn.d_un.d_val = h->root.u.def.value;
8439 o = h->root.u.def.section;
8440 if (o->output_section != NULL)
8441 dyn.d_un.d_val += (o->output_section->vma
8442 + o->output_offset);
8443 else
8445 /* The symbol is imported from another shared
8446 library and does not apply to this one. */
8447 dyn.d_un.d_val = 0;
8449 break;
8452 continue;
8454 case DT_PREINIT_ARRAYSZ:
8455 name = ".preinit_array";
8456 goto get_size;
8457 case DT_INIT_ARRAYSZ:
8458 name = ".init_array";
8459 goto get_size;
8460 case DT_FINI_ARRAYSZ:
8461 name = ".fini_array";
8462 get_size:
8463 o = bfd_get_section_by_name (abfd, name);
8464 if (o == NULL)
8466 (*_bfd_error_handler)
8467 (_("%B: could not find output section %s"), abfd, name);
8468 goto error_return;
8470 if (o->size == 0)
8471 (*_bfd_error_handler)
8472 (_("warning: %s section has zero size"), name);
8473 dyn.d_un.d_val = o->size;
8474 break;
8476 case DT_PREINIT_ARRAY:
8477 name = ".preinit_array";
8478 goto get_vma;
8479 case DT_INIT_ARRAY:
8480 name = ".init_array";
8481 goto get_vma;
8482 case DT_FINI_ARRAY:
8483 name = ".fini_array";
8484 goto get_vma;
8486 case DT_HASH:
8487 name = ".hash";
8488 goto get_vma;
8489 case DT_STRTAB:
8490 name = ".dynstr";
8491 goto get_vma;
8492 case DT_SYMTAB:
8493 name = ".dynsym";
8494 goto get_vma;
8495 case DT_VERDEF:
8496 name = ".gnu.version_d";
8497 goto get_vma;
8498 case DT_VERNEED:
8499 name = ".gnu.version_r";
8500 goto get_vma;
8501 case DT_VERSYM:
8502 name = ".gnu.version";
8503 get_vma:
8504 o = bfd_get_section_by_name (abfd, name);
8505 if (o == NULL)
8507 (*_bfd_error_handler)
8508 (_("%B: could not find output section %s"), abfd, name);
8509 goto error_return;
8511 dyn.d_un.d_ptr = o->vma;
8512 break;
8514 case DT_REL:
8515 case DT_RELA:
8516 case DT_RELSZ:
8517 case DT_RELASZ:
8518 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8519 type = SHT_REL;
8520 else
8521 type = SHT_RELA;
8522 dyn.d_un.d_val = 0;
8523 for (i = 1; i < elf_numsections (abfd); i++)
8525 Elf_Internal_Shdr *hdr;
8527 hdr = elf_elfsections (abfd)[i];
8528 if (hdr->sh_type == type
8529 && (hdr->sh_flags & SHF_ALLOC) != 0)
8531 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8532 dyn.d_un.d_val += hdr->sh_size;
8533 else
8535 if (dyn.d_un.d_val == 0
8536 || hdr->sh_addr < dyn.d_un.d_val)
8537 dyn.d_un.d_val = hdr->sh_addr;
8541 break;
8543 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8547 /* If we have created any dynamic sections, then output them. */
8548 if (dynobj != NULL)
8550 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8551 goto error_return;
8553 for (o = dynobj->sections; o != NULL; o = o->next)
8555 if ((o->flags & SEC_HAS_CONTENTS) == 0
8556 || o->size == 0
8557 || o->output_section == bfd_abs_section_ptr)
8558 continue;
8559 if ((o->flags & SEC_LINKER_CREATED) == 0)
8561 /* At this point, we are only interested in sections
8562 created by _bfd_elf_link_create_dynamic_sections. */
8563 continue;
8565 if (elf_hash_table (info)->stab_info.stabstr == o)
8566 continue;
8567 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8568 continue;
8569 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8570 != SHT_STRTAB)
8571 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8573 if (! bfd_set_section_contents (abfd, o->output_section,
8574 o->contents,
8575 (file_ptr) o->output_offset,
8576 o->size))
8577 goto error_return;
8579 else
8581 /* The contents of the .dynstr section are actually in a
8582 stringtab. */
8583 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8584 if (bfd_seek (abfd, off, SEEK_SET) != 0
8585 || ! _bfd_elf_strtab_emit (abfd,
8586 elf_hash_table (info)->dynstr))
8587 goto error_return;
8592 if (info->relocatable)
8594 bfd_boolean failed = FALSE;
8596 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8597 if (failed)
8598 goto error_return;
8601 /* If we have optimized stabs strings, output them. */
8602 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8604 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8605 goto error_return;
8608 if (info->eh_frame_hdr)
8610 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8611 goto error_return;
8614 if (finfo.symstrtab != NULL)
8615 _bfd_stringtab_free (finfo.symstrtab);
8616 if (finfo.contents != NULL)
8617 free (finfo.contents);
8618 if (finfo.external_relocs != NULL)
8619 free (finfo.external_relocs);
8620 if (finfo.internal_relocs != NULL)
8621 free (finfo.internal_relocs);
8622 if (finfo.external_syms != NULL)
8623 free (finfo.external_syms);
8624 if (finfo.locsym_shndx != NULL)
8625 free (finfo.locsym_shndx);
8626 if (finfo.internal_syms != NULL)
8627 free (finfo.internal_syms);
8628 if (finfo.indices != NULL)
8629 free (finfo.indices);
8630 if (finfo.sections != NULL)
8631 free (finfo.sections);
8632 if (finfo.symbuf != NULL)
8633 free (finfo.symbuf);
8634 if (finfo.symshndxbuf != NULL)
8635 free (finfo.symshndxbuf);
8636 for (o = abfd->sections; o != NULL; o = o->next)
8638 if ((o->flags & SEC_RELOC) != 0
8639 && elf_section_data (o)->rel_hashes != NULL)
8640 free (elf_section_data (o)->rel_hashes);
8643 elf_tdata (abfd)->linker = TRUE;
8645 return TRUE;
8647 error_return:
8648 if (finfo.symstrtab != NULL)
8649 _bfd_stringtab_free (finfo.symstrtab);
8650 if (finfo.contents != NULL)
8651 free (finfo.contents);
8652 if (finfo.external_relocs != NULL)
8653 free (finfo.external_relocs);
8654 if (finfo.internal_relocs != NULL)
8655 free (finfo.internal_relocs);
8656 if (finfo.external_syms != NULL)
8657 free (finfo.external_syms);
8658 if (finfo.locsym_shndx != NULL)
8659 free (finfo.locsym_shndx);
8660 if (finfo.internal_syms != NULL)
8661 free (finfo.internal_syms);
8662 if (finfo.indices != NULL)
8663 free (finfo.indices);
8664 if (finfo.sections != NULL)
8665 free (finfo.sections);
8666 if (finfo.symbuf != NULL)
8667 free (finfo.symbuf);
8668 if (finfo.symshndxbuf != NULL)
8669 free (finfo.symshndxbuf);
8670 for (o = abfd->sections; o != NULL; o = o->next)
8672 if ((o->flags & SEC_RELOC) != 0
8673 && elf_section_data (o)->rel_hashes != NULL)
8674 free (elf_section_data (o)->rel_hashes);
8677 return FALSE;
8680 /* Garbage collect unused sections. */
8682 /* The mark phase of garbage collection. For a given section, mark
8683 it and any sections in this section's group, and all the sections
8684 which define symbols to which it refers. */
8686 typedef asection * (*gc_mark_hook_fn)
8687 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8688 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8690 bfd_boolean
8691 _bfd_elf_gc_mark (struct bfd_link_info *info,
8692 asection *sec,
8693 gc_mark_hook_fn gc_mark_hook)
8695 bfd_boolean ret;
8696 asection *group_sec;
8698 sec->gc_mark = 1;
8700 /* Mark all the sections in the group. */
8701 group_sec = elf_section_data (sec)->next_in_group;
8702 if (group_sec && !group_sec->gc_mark)
8703 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
8704 return FALSE;
8706 /* Look through the section relocs. */
8707 ret = TRUE;
8708 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8710 Elf_Internal_Rela *relstart, *rel, *relend;
8711 Elf_Internal_Shdr *symtab_hdr;
8712 struct elf_link_hash_entry **sym_hashes;
8713 size_t nlocsyms;
8714 size_t extsymoff;
8715 bfd *input_bfd = sec->owner;
8716 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8717 Elf_Internal_Sym *isym = NULL;
8718 int r_sym_shift;
8720 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8721 sym_hashes = elf_sym_hashes (input_bfd);
8723 /* Read the local symbols. */
8724 if (elf_bad_symtab (input_bfd))
8726 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8727 extsymoff = 0;
8729 else
8730 extsymoff = nlocsyms = symtab_hdr->sh_info;
8732 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8733 if (isym == NULL && nlocsyms != 0)
8735 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8736 NULL, NULL, NULL);
8737 if (isym == NULL)
8738 return FALSE;
8741 /* Read the relocations. */
8742 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8743 info->keep_memory);
8744 if (relstart == NULL)
8746 ret = FALSE;
8747 goto out1;
8749 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8751 if (bed->s->arch_size == 32)
8752 r_sym_shift = 8;
8753 else
8754 r_sym_shift = 32;
8756 for (rel = relstart; rel < relend; rel++)
8758 unsigned long r_symndx;
8759 asection *rsec;
8760 struct elf_link_hash_entry *h;
8762 r_symndx = rel->r_info >> r_sym_shift;
8763 if (r_symndx == 0)
8764 continue;
8766 if (r_symndx >= nlocsyms
8767 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8769 h = sym_hashes[r_symndx - extsymoff];
8770 while (h->root.type == bfd_link_hash_indirect
8771 || h->root.type == bfd_link_hash_warning)
8772 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8773 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8775 else
8777 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8780 if (rsec && !rsec->gc_mark)
8782 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8783 rsec->gc_mark = 1;
8784 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
8786 ret = FALSE;
8787 goto out2;
8792 out2:
8793 if (elf_section_data (sec)->relocs != relstart)
8794 free (relstart);
8795 out1:
8796 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8798 if (! info->keep_memory)
8799 free (isym);
8800 else
8801 symtab_hdr->contents = (unsigned char *) isym;
8805 return ret;
8808 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8810 static bfd_boolean
8811 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
8813 int *idx = idxptr;
8815 if (h->root.type == bfd_link_hash_warning)
8816 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8818 if (h->dynindx != -1
8819 && ((h->root.type != bfd_link_hash_defined
8820 && h->root.type != bfd_link_hash_defweak)
8821 || h->root.u.def.section->gc_mark))
8822 h->dynindx = (*idx)++;
8824 return TRUE;
8827 /* The sweep phase of garbage collection. Remove all garbage sections. */
8829 typedef bfd_boolean (*gc_sweep_hook_fn)
8830 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8832 static bfd_boolean
8833 elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
8835 bfd *sub;
8837 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8839 asection *o;
8841 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8842 continue;
8844 for (o = sub->sections; o != NULL; o = o->next)
8846 /* Keep debug and special sections. */
8847 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
8848 || (o->flags & (SEC_ALLOC | SEC_LOAD)) == 0)
8849 o->gc_mark = 1;
8851 if (o->gc_mark)
8852 continue;
8854 /* Skip sweeping sections already excluded. */
8855 if (o->flags & SEC_EXCLUDE)
8856 continue;
8858 /* Since this is early in the link process, it is simple
8859 to remove a section from the output. */
8860 o->flags |= SEC_EXCLUDE;
8862 /* But we also have to update some of the relocation
8863 info we collected before. */
8864 if (gc_sweep_hook
8865 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
8867 Elf_Internal_Rela *internal_relocs;
8868 bfd_boolean r;
8870 internal_relocs
8871 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8872 info->keep_memory);
8873 if (internal_relocs == NULL)
8874 return FALSE;
8876 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8878 if (elf_section_data (o)->relocs != internal_relocs)
8879 free (internal_relocs);
8881 if (!r)
8882 return FALSE;
8887 /* Remove the symbols that were in the swept sections from the dynamic
8888 symbol table. GCFIXME: Anyone know how to get them out of the
8889 static symbol table as well? */
8891 int i = 0;
8893 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
8895 elf_hash_table (info)->dynsymcount = i;
8898 return TRUE;
8901 /* Propagate collected vtable information. This is called through
8902 elf_link_hash_traverse. */
8904 static bfd_boolean
8905 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
8907 if (h->root.type == bfd_link_hash_warning)
8908 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8910 /* Those that are not vtables. */
8911 if (h->vtable == NULL || h->vtable->parent == NULL)
8912 return TRUE;
8914 /* Those vtables that do not have parents, we cannot merge. */
8915 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
8916 return TRUE;
8918 /* If we've already been done, exit. */
8919 if (h->vtable->used && h->vtable->used[-1])
8920 return TRUE;
8922 /* Make sure the parent's table is up to date. */
8923 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
8925 if (h->vtable->used == NULL)
8927 /* None of this table's entries were referenced. Re-use the
8928 parent's table. */
8929 h->vtable->used = h->vtable->parent->vtable->used;
8930 h->vtable->size = h->vtable->parent->vtable->size;
8932 else
8934 size_t n;
8935 bfd_boolean *cu, *pu;
8937 /* Or the parent's entries into ours. */
8938 cu = h->vtable->used;
8939 cu[-1] = TRUE;
8940 pu = h->vtable->parent->vtable->used;
8941 if (pu != NULL)
8943 const struct elf_backend_data *bed;
8944 unsigned int log_file_align;
8946 bed = get_elf_backend_data (h->root.u.def.section->owner);
8947 log_file_align = bed->s->log_file_align;
8948 n = h->vtable->parent->vtable->size >> log_file_align;
8949 while (n--)
8951 if (*pu)
8952 *cu = TRUE;
8953 pu++;
8954 cu++;
8959 return TRUE;
8962 static bfd_boolean
8963 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
8965 asection *sec;
8966 bfd_vma hstart, hend;
8967 Elf_Internal_Rela *relstart, *relend, *rel;
8968 const struct elf_backend_data *bed;
8969 unsigned int log_file_align;
8971 if (h->root.type == bfd_link_hash_warning)
8972 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8974 /* Take care of both those symbols that do not describe vtables as
8975 well as those that are not loaded. */
8976 if (h->vtable == NULL || h->vtable->parent == NULL)
8977 return TRUE;
8979 BFD_ASSERT (h->root.type == bfd_link_hash_defined
8980 || h->root.type == bfd_link_hash_defweak);
8982 sec = h->root.u.def.section;
8983 hstart = h->root.u.def.value;
8984 hend = hstart + h->size;
8986 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
8987 if (!relstart)
8988 return *(bfd_boolean *) okp = FALSE;
8989 bed = get_elf_backend_data (sec->owner);
8990 log_file_align = bed->s->log_file_align;
8992 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8994 for (rel = relstart; rel < relend; ++rel)
8995 if (rel->r_offset >= hstart && rel->r_offset < hend)
8997 /* If the entry is in use, do nothing. */
8998 if (h->vtable->used
8999 && (rel->r_offset - hstart) < h->vtable->size)
9001 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
9002 if (h->vtable->used[entry])
9003 continue;
9005 /* Otherwise, kill it. */
9006 rel->r_offset = rel->r_info = rel->r_addend = 0;
9009 return TRUE;
9012 /* Mark sections containing dynamically referenced symbols. This is called
9013 through elf_link_hash_traverse. */
9015 static bfd_boolean
9016 elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h,
9017 void *okp ATTRIBUTE_UNUSED)
9019 if (h->root.type == bfd_link_hash_warning)
9020 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9022 if ((h->root.type == bfd_link_hash_defined
9023 || h->root.type == bfd_link_hash_defweak)
9024 && h->ref_dynamic)
9025 h->root.u.def.section->flags |= SEC_KEEP;
9027 return TRUE;
9030 /* Mark sections containing global symbols. This is called through
9031 elf_link_hash_traverse. */
9033 static bfd_boolean
9034 elf_mark_used_section (struct elf_link_hash_entry *h,
9035 void *data ATTRIBUTE_UNUSED)
9037 if (h->root.type == bfd_link_hash_warning)
9038 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9040 if (h->root.type == bfd_link_hash_defined
9041 || h->root.type == bfd_link_hash_defweak)
9043 asection *s = h->root.u.def.section;
9044 if (s != NULL && s->output_section != NULL)
9045 s->output_section->flags |= SEC_KEEP;
9048 return TRUE;
9051 /* Do mark and sweep of unused sections. */
9053 bfd_boolean
9054 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
9056 bfd_boolean ok = TRUE;
9057 bfd *sub;
9058 asection * (*gc_mark_hook)
9059 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9060 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
9062 if (!info->gc_sections)
9064 /* If we are called when info->gc_sections is 0, we will mark
9065 all sections containing global symbols for non-relocatable
9066 link. */
9067 if (!info->relocatable)
9068 elf_link_hash_traverse (elf_hash_table (info),
9069 elf_mark_used_section, NULL);
9070 return TRUE;
9073 if (!get_elf_backend_data (abfd)->can_gc_sections
9074 || info->relocatable
9075 || info->emitrelocations
9076 || info->shared
9077 || !is_elf_hash_table (info->hash))
9079 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
9080 return TRUE;
9083 /* Apply transitive closure to the vtable entry usage info. */
9084 elf_link_hash_traverse (elf_hash_table (info),
9085 elf_gc_propagate_vtable_entries_used,
9086 &ok);
9087 if (!ok)
9088 return FALSE;
9090 /* Kill the vtable relocations that were not used. */
9091 elf_link_hash_traverse (elf_hash_table (info),
9092 elf_gc_smash_unused_vtentry_relocs,
9093 &ok);
9094 if (!ok)
9095 return FALSE;
9097 /* Mark dynamically referenced symbols. */
9098 if (elf_hash_table (info)->dynamic_sections_created)
9099 elf_link_hash_traverse (elf_hash_table (info),
9100 elf_gc_mark_dynamic_ref_symbol,
9101 &ok);
9102 if (!ok)
9103 return FALSE;
9105 /* Grovel through relocs to find out who stays ... */
9106 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
9107 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9109 asection *o;
9111 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9112 continue;
9114 for (o = sub->sections; o != NULL; o = o->next)
9116 if (o->flags & SEC_KEEP)
9118 /* _bfd_elf_discard_section_eh_frame knows how to discard
9119 orphaned FDEs so don't mark sections referenced by the
9120 EH frame section. */
9121 if (strcmp (o->name, ".eh_frame") == 0)
9122 o->gc_mark = 1;
9123 else if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9124 return FALSE;
9129 /* ... and mark SEC_EXCLUDE for those that go. */
9130 if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
9131 return FALSE;
9133 return TRUE;
9136 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9138 bfd_boolean
9139 bfd_elf_gc_record_vtinherit (bfd *abfd,
9140 asection *sec,
9141 struct elf_link_hash_entry *h,
9142 bfd_vma offset)
9144 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9145 struct elf_link_hash_entry **search, *child;
9146 bfd_size_type extsymcount;
9147 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9149 /* The sh_info field of the symtab header tells us where the
9150 external symbols start. We don't care about the local symbols at
9151 this point. */
9152 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9153 if (!elf_bad_symtab (abfd))
9154 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9156 sym_hashes = elf_sym_hashes (abfd);
9157 sym_hashes_end = sym_hashes + extsymcount;
9159 /* Hunt down the child symbol, which is in this section at the same
9160 offset as the relocation. */
9161 for (search = sym_hashes; search != sym_hashes_end; ++search)
9163 if ((child = *search) != NULL
9164 && (child->root.type == bfd_link_hash_defined
9165 || child->root.type == bfd_link_hash_defweak)
9166 && child->root.u.def.section == sec
9167 && child->root.u.def.value == offset)
9168 goto win;
9171 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9172 abfd, sec, (unsigned long) offset);
9173 bfd_set_error (bfd_error_invalid_operation);
9174 return FALSE;
9176 win:
9177 if (!child->vtable)
9179 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9180 if (!child->vtable)
9181 return FALSE;
9183 if (!h)
9185 /* This *should* only be the absolute section. It could potentially
9186 be that someone has defined a non-global vtable though, which
9187 would be bad. It isn't worth paging in the local symbols to be
9188 sure though; that case should simply be handled by the assembler. */
9190 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9192 else
9193 child->vtable->parent = h;
9195 return TRUE;
9198 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9200 bfd_boolean
9201 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9202 asection *sec ATTRIBUTE_UNUSED,
9203 struct elf_link_hash_entry *h,
9204 bfd_vma addend)
9206 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9207 unsigned int log_file_align = bed->s->log_file_align;
9209 if (!h->vtable)
9211 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9212 if (!h->vtable)
9213 return FALSE;
9216 if (addend >= h->vtable->size)
9218 size_t size, bytes, file_align;
9219 bfd_boolean *ptr = h->vtable->used;
9221 /* While the symbol is undefined, we have to be prepared to handle
9222 a zero size. */
9223 file_align = 1 << log_file_align;
9224 if (h->root.type == bfd_link_hash_undefined)
9225 size = addend + file_align;
9226 else
9228 size = h->size;
9229 if (addend >= size)
9231 /* Oops! We've got a reference past the defined end of
9232 the table. This is probably a bug -- shall we warn? */
9233 size = addend + file_align;
9236 size = (size + file_align - 1) & -file_align;
9238 /* Allocate one extra entry for use as a "done" flag for the
9239 consolidation pass. */
9240 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9242 if (ptr)
9244 ptr = bfd_realloc (ptr - 1, bytes);
9246 if (ptr != NULL)
9248 size_t oldbytes;
9250 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9251 * sizeof (bfd_boolean));
9252 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9255 else
9256 ptr = bfd_zmalloc (bytes);
9258 if (ptr == NULL)
9259 return FALSE;
9261 /* And arrange for that done flag to be at index -1. */
9262 h->vtable->used = ptr + 1;
9263 h->vtable->size = size;
9266 h->vtable->used[addend >> log_file_align] = TRUE;
9268 return TRUE;
9271 struct alloc_got_off_arg {
9272 bfd_vma gotoff;
9273 unsigned int got_elt_size;
9276 /* We need a special top-level link routine to convert got reference counts
9277 to real got offsets. */
9279 static bfd_boolean
9280 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
9282 struct alloc_got_off_arg *gofarg = arg;
9284 if (h->root.type == bfd_link_hash_warning)
9285 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9287 if (h->got.refcount > 0)
9289 h->got.offset = gofarg->gotoff;
9290 gofarg->gotoff += gofarg->got_elt_size;
9292 else
9293 h->got.offset = (bfd_vma) -1;
9295 return TRUE;
9298 /* And an accompanying bit to work out final got entry offsets once
9299 we're done. Should be called from final_link. */
9301 bfd_boolean
9302 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
9303 struct bfd_link_info *info)
9305 bfd *i;
9306 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9307 bfd_vma gotoff;
9308 unsigned int got_elt_size = bed->s->arch_size / 8;
9309 struct alloc_got_off_arg gofarg;
9311 if (! is_elf_hash_table (info->hash))
9312 return FALSE;
9314 /* The GOT offset is relative to the .got section, but the GOT header is
9315 put into the .got.plt section, if the backend uses it. */
9316 if (bed->want_got_plt)
9317 gotoff = 0;
9318 else
9319 gotoff = bed->got_header_size;
9321 /* Do the local .got entries first. */
9322 for (i = info->input_bfds; i; i = i->link_next)
9324 bfd_signed_vma *local_got;
9325 bfd_size_type j, locsymcount;
9326 Elf_Internal_Shdr *symtab_hdr;
9328 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
9329 continue;
9331 local_got = elf_local_got_refcounts (i);
9332 if (!local_got)
9333 continue;
9335 symtab_hdr = &elf_tdata (i)->symtab_hdr;
9336 if (elf_bad_symtab (i))
9337 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9338 else
9339 locsymcount = symtab_hdr->sh_info;
9341 for (j = 0; j < locsymcount; ++j)
9343 if (local_got[j] > 0)
9345 local_got[j] = gotoff;
9346 gotoff += got_elt_size;
9348 else
9349 local_got[j] = (bfd_vma) -1;
9353 /* Then the global .got entries. .plt refcounts are handled by
9354 adjust_dynamic_symbol */
9355 gofarg.gotoff = gotoff;
9356 gofarg.got_elt_size = got_elt_size;
9357 elf_link_hash_traverse (elf_hash_table (info),
9358 elf_gc_allocate_got_offsets,
9359 &gofarg);
9360 return TRUE;
9363 /* Many folk need no more in the way of final link than this, once
9364 got entry reference counting is enabled. */
9366 bfd_boolean
9367 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
9369 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
9370 return FALSE;
9372 /* Invoke the regular ELF backend linker to do all the work. */
9373 return bfd_elf_final_link (abfd, info);
9376 bfd_boolean
9377 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
9379 struct elf_reloc_cookie *rcookie = cookie;
9381 if (rcookie->bad_symtab)
9382 rcookie->rel = rcookie->rels;
9384 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9386 unsigned long r_symndx;
9388 if (! rcookie->bad_symtab)
9389 if (rcookie->rel->r_offset > offset)
9390 return FALSE;
9391 if (rcookie->rel->r_offset != offset)
9392 continue;
9394 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9395 if (r_symndx == SHN_UNDEF)
9396 return TRUE;
9398 if (r_symndx >= rcookie->locsymcount
9399 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9401 struct elf_link_hash_entry *h;
9403 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9405 while (h->root.type == bfd_link_hash_indirect
9406 || h->root.type == bfd_link_hash_warning)
9407 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9409 if ((h->root.type == bfd_link_hash_defined
9410 || h->root.type == bfd_link_hash_defweak)
9411 && elf_discarded_section (h->root.u.def.section))
9412 return TRUE;
9413 else
9414 return FALSE;
9416 else
9418 /* It's not a relocation against a global symbol,
9419 but it could be a relocation against a local
9420 symbol for a discarded section. */
9421 asection *isec;
9422 Elf_Internal_Sym *isym;
9424 /* Need to: get the symbol; get the section. */
9425 isym = &rcookie->locsyms[r_symndx];
9426 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9428 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9429 if (isec != NULL && elf_discarded_section (isec))
9430 return TRUE;
9433 return FALSE;
9435 return FALSE;
9438 /* Discard unneeded references to discarded sections.
9439 Returns TRUE if any section's size was changed. */
9440 /* This function assumes that the relocations are in sorted order,
9441 which is true for all known assemblers. */
9443 bfd_boolean
9444 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9446 struct elf_reloc_cookie cookie;
9447 asection *stab, *eh;
9448 Elf_Internal_Shdr *symtab_hdr;
9449 const struct elf_backend_data *bed;
9450 bfd *abfd;
9451 unsigned int count;
9452 bfd_boolean ret = FALSE;
9454 if (info->traditional_format
9455 || !is_elf_hash_table (info->hash))
9456 return FALSE;
9458 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9460 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9461 continue;
9463 bed = get_elf_backend_data (abfd);
9465 if ((abfd->flags & DYNAMIC) != 0)
9466 continue;
9468 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9469 if (info->relocatable
9470 || (eh != NULL
9471 && (eh->size == 0
9472 || bfd_is_abs_section (eh->output_section))))
9473 eh = NULL;
9475 stab = bfd_get_section_by_name (abfd, ".stab");
9476 if (stab != NULL
9477 && (stab->size == 0
9478 || bfd_is_abs_section (stab->output_section)
9479 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9480 stab = NULL;
9482 if (stab == NULL
9483 && eh == NULL
9484 && bed->elf_backend_discard_info == NULL)
9485 continue;
9487 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9488 cookie.abfd = abfd;
9489 cookie.sym_hashes = elf_sym_hashes (abfd);
9490 cookie.bad_symtab = elf_bad_symtab (abfd);
9491 if (cookie.bad_symtab)
9493 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9494 cookie.extsymoff = 0;
9496 else
9498 cookie.locsymcount = symtab_hdr->sh_info;
9499 cookie.extsymoff = symtab_hdr->sh_info;
9502 if (bed->s->arch_size == 32)
9503 cookie.r_sym_shift = 8;
9504 else
9505 cookie.r_sym_shift = 32;
9507 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9508 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9510 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9511 cookie.locsymcount, 0,
9512 NULL, NULL, NULL);
9513 if (cookie.locsyms == NULL)
9514 return FALSE;
9517 if (stab != NULL)
9519 cookie.rels = NULL;
9520 count = stab->reloc_count;
9521 if (count != 0)
9522 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9523 info->keep_memory);
9524 if (cookie.rels != NULL)
9526 cookie.rel = cookie.rels;
9527 cookie.relend = cookie.rels;
9528 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9529 if (_bfd_discard_section_stabs (abfd, stab,
9530 elf_section_data (stab)->sec_info,
9531 bfd_elf_reloc_symbol_deleted_p,
9532 &cookie))
9533 ret = TRUE;
9534 if (elf_section_data (stab)->relocs != cookie.rels)
9535 free (cookie.rels);
9539 if (eh != NULL)
9541 cookie.rels = NULL;
9542 count = eh->reloc_count;
9543 if (count != 0)
9544 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9545 info->keep_memory);
9546 cookie.rel = cookie.rels;
9547 cookie.relend = cookie.rels;
9548 if (cookie.rels != NULL)
9549 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9551 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9552 bfd_elf_reloc_symbol_deleted_p,
9553 &cookie))
9554 ret = TRUE;
9556 if (cookie.rels != NULL
9557 && elf_section_data (eh)->relocs != cookie.rels)
9558 free (cookie.rels);
9561 if (bed->elf_backend_discard_info != NULL
9562 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9563 ret = TRUE;
9565 if (cookie.locsyms != NULL
9566 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9568 if (! info->keep_memory)
9569 free (cookie.locsyms);
9570 else
9571 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9575 if (info->eh_frame_hdr
9576 && !info->relocatable
9577 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9578 ret = TRUE;
9580 return ret;
9583 void
9584 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9586 flagword flags;
9587 const char *name, *p;
9588 struct bfd_section_already_linked *l;
9589 struct bfd_section_already_linked_hash_entry *already_linked_list;
9590 asection *group;
9592 /* A single member comdat group section may be discarded by a
9593 linkonce section. See below. */
9594 if (sec->output_section == bfd_abs_section_ptr)
9595 return;
9597 flags = sec->flags;
9599 /* Check if it belongs to a section group. */
9600 group = elf_sec_group (sec);
9602 /* Return if it isn't a linkonce section nor a member of a group. A
9603 comdat group section also has SEC_LINK_ONCE set. */
9604 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9605 return;
9607 if (group)
9609 /* If this is the member of a single member comdat group, check if
9610 the group should be discarded. */
9611 if (elf_next_in_group (sec) == sec
9612 && (group->flags & SEC_LINK_ONCE) != 0)
9613 sec = group;
9614 else
9615 return;
9618 /* FIXME: When doing a relocatable link, we may have trouble
9619 copying relocations in other sections that refer to local symbols
9620 in the section being discarded. Those relocations will have to
9621 be converted somehow; as of this writing I'm not sure that any of
9622 the backends handle that correctly.
9624 It is tempting to instead not discard link once sections when
9625 doing a relocatable link (technically, they should be discarded
9626 whenever we are building constructors). However, that fails,
9627 because the linker winds up combining all the link once sections
9628 into a single large link once section, which defeats the purpose
9629 of having link once sections in the first place.
9631 Also, not merging link once sections in a relocatable link
9632 causes trouble for MIPS ELF, which relies on link once semantics
9633 to handle the .reginfo section correctly. */
9635 name = bfd_get_section_name (abfd, sec);
9637 if (strncmp (name, ".gnu.linkonce.", sizeof (".gnu.linkonce.") - 1) == 0
9638 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
9639 p++;
9640 else
9641 p = name;
9643 already_linked_list = bfd_section_already_linked_table_lookup (p);
9645 for (l = already_linked_list->entry; l != NULL; l = l->next)
9647 /* We may have 3 different sections on the list: group section,
9648 comdat section and linkonce section. SEC may be a linkonce or
9649 group section. We match a group section with a group section,
9650 a linkonce section with a linkonce section, and ignore comdat
9651 section. */
9652 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9653 && strcmp (name, l->sec->name) == 0
9654 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9656 /* The section has already been linked. See if we should
9657 issue a warning. */
9658 switch (flags & SEC_LINK_DUPLICATES)
9660 default:
9661 abort ();
9663 case SEC_LINK_DUPLICATES_DISCARD:
9664 break;
9666 case SEC_LINK_DUPLICATES_ONE_ONLY:
9667 (*_bfd_error_handler)
9668 (_("%B: ignoring duplicate section `%A'"),
9669 abfd, sec);
9670 break;
9672 case SEC_LINK_DUPLICATES_SAME_SIZE:
9673 if (sec->size != l->sec->size)
9674 (*_bfd_error_handler)
9675 (_("%B: duplicate section `%A' has different size"),
9676 abfd, sec);
9677 break;
9679 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
9680 if (sec->size != l->sec->size)
9681 (*_bfd_error_handler)
9682 (_("%B: duplicate section `%A' has different size"),
9683 abfd, sec);
9684 else if (sec->size != 0)
9686 bfd_byte *sec_contents, *l_sec_contents;
9688 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
9689 (*_bfd_error_handler)
9690 (_("%B: warning: could not read contents of section `%A'"),
9691 abfd, sec);
9692 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
9693 &l_sec_contents))
9694 (*_bfd_error_handler)
9695 (_("%B: warning: could not read contents of section `%A'"),
9696 l->sec->owner, l->sec);
9697 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
9698 (*_bfd_error_handler)
9699 (_("%B: warning: duplicate section `%A' has different contents"),
9700 abfd, sec);
9702 if (sec_contents)
9703 free (sec_contents);
9704 if (l_sec_contents)
9705 free (l_sec_contents);
9707 break;
9710 /* Set the output_section field so that lang_add_section
9711 does not create a lang_input_section structure for this
9712 section. Since there might be a symbol in the section
9713 being discarded, we must retain a pointer to the section
9714 which we are really going to use. */
9715 sec->output_section = bfd_abs_section_ptr;
9716 sec->kept_section = l->sec;
9718 if (flags & SEC_GROUP)
9720 asection *first = elf_next_in_group (sec);
9721 asection *s = first;
9723 while (s != NULL)
9725 s->output_section = bfd_abs_section_ptr;
9726 /* Record which group discards it. */
9727 s->kept_section = l->sec;
9728 s = elf_next_in_group (s);
9729 /* These lists are circular. */
9730 if (s == first)
9731 break;
9735 return;
9739 if (group)
9741 /* If this is the member of a single member comdat group and the
9742 group hasn't be discarded, we check if it matches a linkonce
9743 section. We only record the discarded comdat group. Otherwise
9744 the undiscarded group will be discarded incorrectly later since
9745 itself has been recorded. */
9746 for (l = already_linked_list->entry; l != NULL; l = l->next)
9747 if ((l->sec->flags & SEC_GROUP) == 0
9748 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9749 && bfd_elf_match_symbols_in_sections (l->sec,
9750 elf_next_in_group (sec)))
9752 elf_next_in_group (sec)->output_section = bfd_abs_section_ptr;
9753 elf_next_in_group (sec)->kept_section = l->sec;
9754 group->output_section = bfd_abs_section_ptr;
9755 break;
9757 if (l == NULL)
9758 return;
9760 else
9761 /* There is no direct match. But for linkonce section, we should
9762 check if there is a match with comdat group member. We always
9763 record the linkonce section, discarded or not. */
9764 for (l = already_linked_list->entry; l != NULL; l = l->next)
9765 if (l->sec->flags & SEC_GROUP)
9767 asection *first = elf_next_in_group (l->sec);
9769 if (first != NULL
9770 && elf_next_in_group (first) == first
9771 && bfd_elf_match_symbols_in_sections (first, sec))
9773 sec->output_section = bfd_abs_section_ptr;
9774 sec->kept_section = l->sec;
9775 break;
9779 /* This is the first section with this name. Record it. */
9780 bfd_section_already_linked_table_insert (already_linked_list, sec);
9783 /* Set NAME to VAL if the symbol exists and is undefined. */
9785 void
9786 _bfd_elf_provide_symbol (struct bfd_link_info *info, const char *name,
9787 bfd_vma val)
9789 struct elf_link_hash_entry *h;
9790 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE,
9791 FALSE);
9792 if (h != NULL && h->root.type == bfd_link_hash_undefined)
9794 h->root.type = bfd_link_hash_defined;
9795 h->root.u.def.section = bfd_abs_section_ptr;
9796 h->root.u.def.value = val;
9797 h->def_regular = 1;
9798 h->type = STT_OBJECT;
9799 h->other = STV_HIDDEN | (h->other & ~ ELF_ST_VISIBILITY (-1));
9800 h->forced_local = 1;