2004-07-27 H.J. Lu <hongjiu.lu@intel.com>
[binutils.git] / bfd / elflink.c
blobe3411826f962961a0f1235a10e97019a4cb0cf07
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
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 = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY
61 | SEC_LINKER_CREATED);
63 s = bfd_make_section (abfd, ".got");
64 if (s == NULL
65 || !bfd_set_section_flags (abfd, s, flags)
66 || !bfd_set_section_alignment (abfd, s, ptralign))
67 return FALSE;
69 if (bed->want_got_plt)
71 s = bfd_make_section (abfd, ".got.plt");
72 if (s == NULL
73 || !bfd_set_section_flags (abfd, s, flags)
74 || !bfd_set_section_alignment (abfd, s, ptralign))
75 return FALSE;
78 if (bed->want_got_sym)
80 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
81 (or .got.plt) section. We don't do this in the linker script
82 because we don't want to define the symbol if we are not creating
83 a global offset table. */
84 bh = NULL;
85 if (!(_bfd_generic_link_add_one_symbol
86 (info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s,
87 bed->got_symbol_offset, NULL, FALSE, bed->collect, &bh)))
88 return FALSE;
89 h = (struct elf_link_hash_entry *) bh;
90 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
91 h->type = STT_OBJECT;
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 some sections which will be filled in with dynamic linking
107 information. ABFD is an input file which requires dynamic sections
108 to be created. The dynamic sections take up virtual memory space
109 when the final executable is run, so we need to create them before
110 addresses are assigned to the output sections. We work out the
111 actual contents and size of these sections later. */
113 bfd_boolean
114 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
116 flagword flags;
117 register asection *s;
118 struct elf_link_hash_entry *h;
119 struct bfd_link_hash_entry *bh;
120 const struct elf_backend_data *bed;
122 if (! is_elf_hash_table (info->hash))
123 return FALSE;
125 if (elf_hash_table (info)->dynamic_sections_created)
126 return TRUE;
128 /* Make sure that all dynamic sections use the same input BFD. */
129 if (elf_hash_table (info)->dynobj == NULL)
130 elf_hash_table (info)->dynobj = abfd;
131 else
132 abfd = elf_hash_table (info)->dynobj;
134 /* Note that we set the SEC_IN_MEMORY flag for all of these
135 sections. */
136 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
137 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
139 /* A dynamically linked executable has a .interp section, but a
140 shared library does not. */
141 if (info->executable)
143 s = bfd_make_section (abfd, ".interp");
144 if (s == NULL
145 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
146 return FALSE;
149 if (! info->traditional_format)
151 s = bfd_make_section (abfd, ".eh_frame_hdr");
152 if (s == NULL
153 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
154 || ! bfd_set_section_alignment (abfd, s, 2))
155 return FALSE;
156 elf_hash_table (info)->eh_info.hdr_sec = s;
159 bed = get_elf_backend_data (abfd);
161 /* Create sections to hold version informations. These are removed
162 if they are not needed. */
163 s = bfd_make_section (abfd, ".gnu.version_d");
164 if (s == NULL
165 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
166 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
167 return FALSE;
169 s = bfd_make_section (abfd, ".gnu.version");
170 if (s == NULL
171 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
172 || ! bfd_set_section_alignment (abfd, s, 1))
173 return FALSE;
175 s = bfd_make_section (abfd, ".gnu.version_r");
176 if (s == NULL
177 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
178 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
179 return FALSE;
181 s = bfd_make_section (abfd, ".dynsym");
182 if (s == NULL
183 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
184 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
185 return FALSE;
187 s = bfd_make_section (abfd, ".dynstr");
188 if (s == NULL
189 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
190 return FALSE;
192 /* Create a strtab to hold the dynamic symbol names. */
193 if (elf_hash_table (info)->dynstr == NULL)
195 elf_hash_table (info)->dynstr = _bfd_elf_strtab_init ();
196 if (elf_hash_table (info)->dynstr == NULL)
197 return FALSE;
200 s = bfd_make_section (abfd, ".dynamic");
201 if (s == NULL
202 || ! bfd_set_section_flags (abfd, s, flags)
203 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
204 return FALSE;
206 /* The special symbol _DYNAMIC is always set to the start of the
207 .dynamic section. This call occurs before we have processed the
208 symbols for any dynamic object, so we don't have to worry about
209 overriding a dynamic definition. We could set _DYNAMIC in a
210 linker script, but we only want to define it if we are, in fact,
211 creating a .dynamic section. We don't want to define it if there
212 is no .dynamic section, since on some ELF platforms the start up
213 code examines it to decide how to initialize the process. */
214 bh = NULL;
215 if (! (_bfd_generic_link_add_one_symbol
216 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, 0, NULL, FALSE,
217 get_elf_backend_data (abfd)->collect, &bh)))
218 return FALSE;
219 h = (struct elf_link_hash_entry *) bh;
220 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
221 h->type = STT_OBJECT;
223 if (! info->executable
224 && ! bfd_elf_link_record_dynamic_symbol (info, h))
225 return FALSE;
227 s = bfd_make_section (abfd, ".hash");
228 if (s == NULL
229 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
230 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
231 return FALSE;
232 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
234 /* Let the backend create the rest of the sections. This lets the
235 backend set the right flags. The backend will normally create
236 the .got and .plt sections. */
237 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
238 return FALSE;
240 elf_hash_table (info)->dynamic_sections_created = TRUE;
242 return TRUE;
245 /* Create dynamic sections when linking against a dynamic object. */
247 bfd_boolean
248 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
250 flagword flags, pltflags;
251 asection *s;
252 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
254 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
255 .rel[a].bss sections. */
257 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY
258 | SEC_LINKER_CREATED);
260 pltflags = flags;
261 pltflags |= SEC_CODE;
262 if (bed->plt_not_loaded)
263 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
264 if (bed->plt_readonly)
265 pltflags |= SEC_READONLY;
267 s = bfd_make_section (abfd, ".plt");
268 if (s == NULL
269 || ! bfd_set_section_flags (abfd, s, pltflags)
270 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
271 return FALSE;
273 if (bed->want_plt_sym)
275 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
276 .plt section. */
277 struct elf_link_hash_entry *h;
278 struct bfd_link_hash_entry *bh = NULL;
280 if (! (_bfd_generic_link_add_one_symbol
281 (info, abfd, "_PROCEDURE_LINKAGE_TABLE_", BSF_GLOBAL, s, 0, NULL,
282 FALSE, get_elf_backend_data (abfd)->collect, &bh)))
283 return FALSE;
284 h = (struct elf_link_hash_entry *) bh;
285 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
286 h->type = STT_OBJECT;
288 if (! info->executable
289 && ! bfd_elf_link_record_dynamic_symbol (info, h))
290 return FALSE;
293 s = bfd_make_section (abfd,
294 bed->default_use_rela_p ? ".rela.plt" : ".rel.plt");
295 if (s == NULL
296 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
297 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
298 return FALSE;
300 if (! _bfd_elf_create_got_section (abfd, info))
301 return FALSE;
303 if (bed->want_dynbss)
305 /* The .dynbss section is a place to put symbols which are defined
306 by dynamic objects, are referenced by regular objects, and are
307 not functions. We must allocate space for them in the process
308 image and use a R_*_COPY reloc to tell the dynamic linker to
309 initialize them at run time. The linker script puts the .dynbss
310 section into the .bss section of the final image. */
311 s = bfd_make_section (abfd, ".dynbss");
312 if (s == NULL
313 || ! bfd_set_section_flags (abfd, s, SEC_ALLOC | SEC_LINKER_CREATED))
314 return FALSE;
316 /* The .rel[a].bss section holds copy relocs. This section is not
317 normally needed. We need to create it here, though, so that the
318 linker will map it to an output section. We can't just create it
319 only if we need it, because we will not know whether we need it
320 until we have seen all the input files, and the first time the
321 main linker code calls BFD after examining all the input files
322 (size_dynamic_sections) the input sections have already been
323 mapped to the output sections. If the section turns out not to
324 be needed, we can discard it later. We will never need this
325 section when generating a shared object, since they do not use
326 copy relocs. */
327 if (! info->shared)
329 s = bfd_make_section (abfd,
330 (bed->default_use_rela_p
331 ? ".rela.bss" : ".rel.bss"));
332 if (s == NULL
333 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
334 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
335 return FALSE;
339 return TRUE;
342 /* Record a new dynamic symbol. We record the dynamic symbols as we
343 read the input files, since we need to have a list of all of them
344 before we can determine the final sizes of the output sections.
345 Note that we may actually call this function even though we are not
346 going to output any dynamic symbols; in some cases we know that a
347 symbol should be in the dynamic symbol table, but only if there is
348 one. */
350 bfd_boolean
351 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
352 struct elf_link_hash_entry *h)
354 if (h->dynindx == -1)
356 struct elf_strtab_hash *dynstr;
357 char *p;
358 const char *name;
359 bfd_size_type indx;
361 /* XXX: The ABI draft says the linker must turn hidden and
362 internal symbols into STB_LOCAL symbols when producing the
363 DSO. However, if ld.so honors st_other in the dynamic table,
364 this would not be necessary. */
365 switch (ELF_ST_VISIBILITY (h->other))
367 case STV_INTERNAL:
368 case STV_HIDDEN:
369 if (h->root.type != bfd_link_hash_undefined
370 && h->root.type != bfd_link_hash_undefweak)
372 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
373 return TRUE;
376 default:
377 break;
380 h->dynindx = elf_hash_table (info)->dynsymcount;
381 ++elf_hash_table (info)->dynsymcount;
383 dynstr = elf_hash_table (info)->dynstr;
384 if (dynstr == NULL)
386 /* Create a strtab to hold the dynamic symbol names. */
387 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
388 if (dynstr == NULL)
389 return FALSE;
392 /* We don't put any version information in the dynamic string
393 table. */
394 name = h->root.root.string;
395 p = strchr (name, ELF_VER_CHR);
396 if (p != NULL)
397 /* We know that the p points into writable memory. In fact,
398 there are only a few symbols that have read-only names, being
399 those like _GLOBAL_OFFSET_TABLE_ that are created specially
400 by the backends. Most symbols will have names pointing into
401 an ELF string table read from a file, or to objalloc memory. */
402 *p = 0;
404 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
406 if (p != NULL)
407 *p = ELF_VER_CHR;
409 if (indx == (bfd_size_type) -1)
410 return FALSE;
411 h->dynstr_index = indx;
414 return TRUE;
417 /* Record an assignment to a symbol made by a linker script. We need
418 this in case some dynamic object refers to this symbol. */
420 bfd_boolean
421 bfd_elf_record_link_assignment (bfd *output_bfd ATTRIBUTE_UNUSED,
422 struct bfd_link_info *info,
423 const char *name,
424 bfd_boolean provide)
426 struct elf_link_hash_entry *h;
428 if (!is_elf_hash_table (info->hash))
429 return TRUE;
431 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, TRUE, FALSE);
432 if (h == NULL)
433 return FALSE;
435 /* Since we're defining the symbol, don't let it seem to have not
436 been defined. record_dynamic_symbol and size_dynamic_sections
437 may depend on this. */
438 if (h->root.type == bfd_link_hash_undefweak
439 || h->root.type == bfd_link_hash_undefined)
440 h->root.type = bfd_link_hash_new;
442 if (h->root.type == bfd_link_hash_new)
443 h->elf_link_hash_flags &= ~ELF_LINK_NON_ELF;
445 /* If this symbol is being provided by the linker script, and it is
446 currently defined by a dynamic object, but not by a regular
447 object, then mark it as undefined so that the generic linker will
448 force the correct value. */
449 if (provide
450 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
451 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
452 h->root.type = bfd_link_hash_undefined;
454 /* If this symbol is not being provided by the linker script, and it is
455 currently defined by a dynamic object, but not by a regular object,
456 then clear out any version information because the symbol will not be
457 associated with the dynamic object any more. */
458 if (!provide
459 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
460 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
461 h->verinfo.verdef = NULL;
463 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
465 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
466 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
467 || info->shared)
468 && h->dynindx == -1)
470 if (! bfd_elf_link_record_dynamic_symbol (info, h))
471 return FALSE;
473 /* If this is a weak defined symbol, and we know a corresponding
474 real symbol from the same dynamic object, make sure the real
475 symbol is also made into a dynamic symbol. */
476 if (h->weakdef != NULL
477 && h->weakdef->dynindx == -1)
479 if (! bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
480 return FALSE;
484 return TRUE;
487 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
488 success, and 2 on a failure caused by attempting to record a symbol
489 in a discarded section, eg. a discarded link-once section symbol. */
492 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
493 bfd *input_bfd,
494 long input_indx)
496 bfd_size_type amt;
497 struct elf_link_local_dynamic_entry *entry;
498 struct elf_link_hash_table *eht;
499 struct elf_strtab_hash *dynstr;
500 unsigned long dynstr_index;
501 char *name;
502 Elf_External_Sym_Shndx eshndx;
503 char esym[sizeof (Elf64_External_Sym)];
505 if (! is_elf_hash_table (info->hash))
506 return 0;
508 /* See if the entry exists already. */
509 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
510 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
511 return 1;
513 amt = sizeof (*entry);
514 entry = bfd_alloc (input_bfd, amt);
515 if (entry == NULL)
516 return 0;
518 /* Go find the symbol, so that we can find it's name. */
519 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
520 1, input_indx, &entry->isym, esym, &eshndx))
522 bfd_release (input_bfd, entry);
523 return 0;
526 if (entry->isym.st_shndx != SHN_UNDEF
527 && (entry->isym.st_shndx < SHN_LORESERVE
528 || entry->isym.st_shndx > SHN_HIRESERVE))
530 asection *s;
532 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
533 if (s == NULL || bfd_is_abs_section (s->output_section))
535 /* We can still bfd_release here as nothing has done another
536 bfd_alloc. We can't do this later in this function. */
537 bfd_release (input_bfd, entry);
538 return 2;
542 name = (bfd_elf_string_from_elf_section
543 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
544 entry->isym.st_name));
546 dynstr = elf_hash_table (info)->dynstr;
547 if (dynstr == NULL)
549 /* Create a strtab to hold the dynamic symbol names. */
550 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
551 if (dynstr == NULL)
552 return 0;
555 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
556 if (dynstr_index == (unsigned long) -1)
557 return 0;
558 entry->isym.st_name = dynstr_index;
560 eht = elf_hash_table (info);
562 entry->next = eht->dynlocal;
563 eht->dynlocal = entry;
564 entry->input_bfd = input_bfd;
565 entry->input_indx = input_indx;
566 eht->dynsymcount++;
568 /* Whatever binding the symbol had before, it's now local. */
569 entry->isym.st_info
570 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
572 /* The dynindx will be set at the end of size_dynamic_sections. */
574 return 1;
577 /* Return the dynindex of a local dynamic symbol. */
579 long
580 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
581 bfd *input_bfd,
582 long input_indx)
584 struct elf_link_local_dynamic_entry *e;
586 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
587 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
588 return e->dynindx;
589 return -1;
592 /* This function is used to renumber the dynamic symbols, if some of
593 them are removed because they are marked as local. This is called
594 via elf_link_hash_traverse. */
596 static bfd_boolean
597 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
598 void *data)
600 size_t *count = data;
602 if (h->root.type == bfd_link_hash_warning)
603 h = (struct elf_link_hash_entry *) h->root.u.i.link;
605 if (h->dynindx != -1)
606 h->dynindx = ++(*count);
608 return TRUE;
611 /* Return true if the dynamic symbol for a given section should be
612 omitted when creating a shared library. */
613 bfd_boolean
614 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
615 struct bfd_link_info *info,
616 asection *p)
618 switch (elf_section_data (p)->this_hdr.sh_type)
620 case SHT_PROGBITS:
621 case SHT_NOBITS:
622 /* If sh_type is yet undecided, assume it could be
623 SHT_PROGBITS/SHT_NOBITS. */
624 case SHT_NULL:
625 if (strcmp (p->name, ".got") == 0
626 || strcmp (p->name, ".got.plt") == 0
627 || strcmp (p->name, ".plt") == 0)
629 asection *ip;
630 bfd *dynobj = elf_hash_table (info)->dynobj;
632 if (dynobj != NULL
633 && (ip = bfd_get_section_by_name (dynobj, p->name))
634 != NULL
635 && (ip->flags & SEC_LINKER_CREATED)
636 && ip->output_section == p)
637 return TRUE;
639 return FALSE;
641 /* There shouldn't be section relative relocations
642 against any other section. */
643 default:
644 return TRUE;
648 /* Assign dynsym indices. In a shared library we generate a section
649 symbol for each output section, which come first. Next come all of
650 the back-end allocated local dynamic syms, followed by the rest of
651 the global symbols. */
653 unsigned long
654 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd, struct bfd_link_info *info)
656 unsigned long dynsymcount = 0;
658 if (info->shared)
660 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
661 asection *p;
662 for (p = output_bfd->sections; p ; p = p->next)
663 if ((p->flags & SEC_EXCLUDE) == 0
664 && (p->flags & SEC_ALLOC) != 0
665 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
666 elf_section_data (p)->dynindx = ++dynsymcount;
669 if (elf_hash_table (info)->dynlocal)
671 struct elf_link_local_dynamic_entry *p;
672 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
673 p->dynindx = ++dynsymcount;
676 elf_link_hash_traverse (elf_hash_table (info),
677 elf_link_renumber_hash_table_dynsyms,
678 &dynsymcount);
680 /* There is an unused NULL entry at the head of the table which
681 we must account for in our count. Unless there weren't any
682 symbols, which means we'll have no table at all. */
683 if (dynsymcount != 0)
684 ++dynsymcount;
686 return elf_hash_table (info)->dynsymcount = dynsymcount;
689 /* This function is called when we want to define a new symbol. It
690 handles the various cases which arise when we find a definition in
691 a dynamic object, or when there is already a definition in a
692 dynamic object. The new symbol is described by NAME, SYM, PSEC,
693 and PVALUE. We set SYM_HASH to the hash table entry. We set
694 OVERRIDE if the old symbol is overriding a new definition. We set
695 TYPE_CHANGE_OK if it is OK for the type to change. We set
696 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
697 change, we mean that we shouldn't warn if the type or size does
698 change. */
700 bfd_boolean
701 _bfd_elf_merge_symbol (bfd *abfd,
702 struct bfd_link_info *info,
703 const char *name,
704 Elf_Internal_Sym *sym,
705 asection **psec,
706 bfd_vma *pvalue,
707 struct elf_link_hash_entry **sym_hash,
708 bfd_boolean *skip,
709 bfd_boolean *override,
710 bfd_boolean *type_change_ok,
711 bfd_boolean *size_change_ok)
713 asection *sec;
714 struct elf_link_hash_entry *h;
715 struct elf_link_hash_entry *flip;
716 int bind;
717 bfd *oldbfd;
718 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
719 bfd_boolean newweak, oldweak;
721 *skip = FALSE;
722 *override = FALSE;
724 sec = *psec;
725 bind = ELF_ST_BIND (sym->st_info);
727 if (! bfd_is_und_section (sec))
728 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
729 else
730 h = ((struct elf_link_hash_entry *)
731 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
732 if (h == NULL)
733 return FALSE;
734 *sym_hash = h;
736 /* This code is for coping with dynamic objects, and is only useful
737 if we are doing an ELF link. */
738 if (info->hash->creator != abfd->xvec)
739 return TRUE;
741 /* For merging, we only care about real symbols. */
743 while (h->root.type == bfd_link_hash_indirect
744 || h->root.type == bfd_link_hash_warning)
745 h = (struct elf_link_hash_entry *) h->root.u.i.link;
747 /* If we just created the symbol, mark it as being an ELF symbol.
748 Other than that, there is nothing to do--there is no merge issue
749 with a newly defined symbol--so we just return. */
751 if (h->root.type == bfd_link_hash_new)
753 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
754 return TRUE;
757 /* OLDBFD is a BFD associated with the existing symbol. */
759 switch (h->root.type)
761 default:
762 oldbfd = NULL;
763 break;
765 case bfd_link_hash_undefined:
766 case bfd_link_hash_undefweak:
767 oldbfd = h->root.u.undef.abfd;
768 break;
770 case bfd_link_hash_defined:
771 case bfd_link_hash_defweak:
772 oldbfd = h->root.u.def.section->owner;
773 break;
775 case bfd_link_hash_common:
776 oldbfd = h->root.u.c.p->section->owner;
777 break;
780 /* In cases involving weak versioned symbols, we may wind up trying
781 to merge a symbol with itself. Catch that here, to avoid the
782 confusion that results if we try to override a symbol with
783 itself. The additional tests catch cases like
784 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
785 dynamic object, which we do want to handle here. */
786 if (abfd == oldbfd
787 && ((abfd->flags & DYNAMIC) == 0
788 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
789 return TRUE;
791 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
792 respectively, is from a dynamic object. */
794 if ((abfd->flags & DYNAMIC) != 0)
795 newdyn = TRUE;
796 else
797 newdyn = FALSE;
799 if (oldbfd != NULL)
800 olddyn = (oldbfd->flags & DYNAMIC) != 0;
801 else
803 asection *hsec;
805 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
806 indices used by MIPS ELF. */
807 switch (h->root.type)
809 default:
810 hsec = NULL;
811 break;
813 case bfd_link_hash_defined:
814 case bfd_link_hash_defweak:
815 hsec = h->root.u.def.section;
816 break;
818 case bfd_link_hash_common:
819 hsec = h->root.u.c.p->section;
820 break;
823 if (hsec == NULL)
824 olddyn = FALSE;
825 else
826 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
829 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
830 respectively, appear to be a definition rather than reference. */
832 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
833 newdef = FALSE;
834 else
835 newdef = TRUE;
837 if (h->root.type == bfd_link_hash_undefined
838 || h->root.type == bfd_link_hash_undefweak
839 || h->root.type == bfd_link_hash_common)
840 olddef = FALSE;
841 else
842 olddef = TRUE;
844 /* We need to remember if a symbol has a definition in a dynamic
845 object or is weak in all dynamic objects. Internal and hidden
846 visibility will make it unavailable to dynamic objects. */
847 if (newdyn && (h->elf_link_hash_flags & ELF_LINK_DYNAMIC_DEF) == 0)
849 if (!bfd_is_und_section (sec))
850 h->elf_link_hash_flags |= ELF_LINK_DYNAMIC_DEF;
851 else
853 /* Check if this symbol is weak in all dynamic objects. If it
854 is the first time we see it in a dynamic object, we mark
855 if it is weak. Otherwise, we clear it. */
856 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0)
858 if (bind == STB_WEAK)
859 h->elf_link_hash_flags |= ELF_LINK_DYNAMIC_WEAK;
861 else if (bind != STB_WEAK)
862 h->elf_link_hash_flags &= ~ELF_LINK_DYNAMIC_WEAK;
866 /* If the old symbol has non-default visibility, we ignore the new
867 definition from a dynamic object. */
868 if (newdyn
869 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
870 && !bfd_is_und_section (sec))
872 *skip = TRUE;
873 /* Make sure this symbol is dynamic. */
874 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
875 /* A protected symbol has external availability. Make sure it is
876 recorded as dynamic.
878 FIXME: Should we check type and size for protected symbol? */
879 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
880 return bfd_elf_link_record_dynamic_symbol (info, h);
881 else
882 return TRUE;
884 else if (!newdyn
885 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
886 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
888 /* If the new symbol with non-default visibility comes from a
889 relocatable file and the old definition comes from a dynamic
890 object, we remove the old definition. */
891 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
892 h = *sym_hash;
894 if ((h->root.und_next || info->hash->undefs_tail == &h->root)
895 && bfd_is_und_section (sec))
897 /* If the new symbol is undefined and the old symbol was
898 also undefined before, we need to make sure
899 _bfd_generic_link_add_one_symbol doesn't mess
900 up the linker hash table undefs list. Since the old
901 definition came from a dynamic object, it is still on the
902 undefs list. */
903 h->root.type = bfd_link_hash_undefined;
904 /* FIXME: What if the new symbol is weak undefined? */
905 h->root.u.undef.abfd = abfd;
907 else
909 h->root.type = bfd_link_hash_new;
910 h->root.u.undef.abfd = NULL;
913 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
915 h->elf_link_hash_flags &= ~ELF_LINK_HASH_DEF_DYNAMIC;
916 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_DYNAMIC
917 | ELF_LINK_DYNAMIC_DEF);
919 /* FIXME: Should we check type and size for protected symbol? */
920 h->size = 0;
921 h->type = 0;
922 return TRUE;
925 /* Differentiate strong and weak symbols. */
926 newweak = bind == STB_WEAK;
927 oldweak = (h->root.type == bfd_link_hash_defweak
928 || h->root.type == bfd_link_hash_undefweak);
930 /* If a new weak symbol definition comes from a regular file and the
931 old symbol comes from a dynamic library, we treat the new one as
932 strong. Similarly, an old weak symbol definition from a regular
933 file is treated as strong when the new symbol comes from a dynamic
934 library. Further, an old weak symbol from a dynamic library is
935 treated as strong if the new symbol is from a dynamic library.
936 This reflects the way glibc's ld.so works.
938 Do this before setting *type_change_ok or *size_change_ok so that
939 we warn properly when dynamic library symbols are overridden. */
941 if (newdef && !newdyn && olddyn)
942 newweak = FALSE;
943 if (olddef && newdyn)
944 oldweak = FALSE;
946 /* It's OK to change the type if either the existing symbol or the
947 new symbol is weak. A type change is also OK if the old symbol
948 is undefined and the new symbol is defined. */
950 if (oldweak
951 || newweak
952 || (newdef
953 && h->root.type == bfd_link_hash_undefined))
954 *type_change_ok = TRUE;
956 /* It's OK to change the size if either the existing symbol or the
957 new symbol is weak, or if the old symbol is undefined. */
959 if (*type_change_ok
960 || h->root.type == bfd_link_hash_undefined)
961 *size_change_ok = TRUE;
963 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
964 symbol, respectively, appears to be a common symbol in a dynamic
965 object. If a symbol appears in an uninitialized section, and is
966 not weak, and is not a function, then it may be a common symbol
967 which was resolved when the dynamic object was created. We want
968 to treat such symbols specially, because they raise special
969 considerations when setting the symbol size: if the symbol
970 appears as a common symbol in a regular object, and the size in
971 the regular object is larger, we must make sure that we use the
972 larger size. This problematic case can always be avoided in C,
973 but it must be handled correctly when using Fortran shared
974 libraries.
976 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
977 likewise for OLDDYNCOMMON and OLDDEF.
979 Note that this test is just a heuristic, and that it is quite
980 possible to have an uninitialized symbol in a shared object which
981 is really a definition, rather than a common symbol. This could
982 lead to some minor confusion when the symbol really is a common
983 symbol in some regular object. However, I think it will be
984 harmless. */
986 if (newdyn
987 && newdef
988 && !newweak
989 && (sec->flags & SEC_ALLOC) != 0
990 && (sec->flags & SEC_LOAD) == 0
991 && sym->st_size > 0
992 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
993 newdyncommon = TRUE;
994 else
995 newdyncommon = FALSE;
997 if (olddyn
998 && olddef
999 && h->root.type == bfd_link_hash_defined
1000 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1001 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1002 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1003 && h->size > 0
1004 && h->type != STT_FUNC)
1005 olddyncommon = TRUE;
1006 else
1007 olddyncommon = FALSE;
1009 /* If both the old and the new symbols look like common symbols in a
1010 dynamic object, set the size of the symbol to the larger of the
1011 two. */
1013 if (olddyncommon
1014 && newdyncommon
1015 && sym->st_size != h->size)
1017 /* Since we think we have two common symbols, issue a multiple
1018 common warning if desired. Note that we only warn if the
1019 size is different. If the size is the same, we simply let
1020 the old symbol override the new one as normally happens with
1021 symbols defined in dynamic objects. */
1023 if (! ((*info->callbacks->multiple_common)
1024 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1025 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1026 return FALSE;
1028 if (sym->st_size > h->size)
1029 h->size = sym->st_size;
1031 *size_change_ok = TRUE;
1034 /* If we are looking at a dynamic object, and we have found a
1035 definition, we need to see if the symbol was already defined by
1036 some other object. If so, we want to use the existing
1037 definition, and we do not want to report a multiple symbol
1038 definition error; we do this by clobbering *PSEC to be
1039 bfd_und_section_ptr.
1041 We treat a common symbol as a definition if the symbol in the
1042 shared library is a function, since common symbols always
1043 represent variables; this can cause confusion in principle, but
1044 any such confusion would seem to indicate an erroneous program or
1045 shared library. We also permit a common symbol in a regular
1046 object to override a weak symbol in a shared object. */
1048 if (newdyn
1049 && newdef
1050 && (olddef
1051 || (h->root.type == bfd_link_hash_common
1052 && (newweak
1053 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1055 *override = TRUE;
1056 newdef = FALSE;
1057 newdyncommon = FALSE;
1059 *psec = sec = bfd_und_section_ptr;
1060 *size_change_ok = TRUE;
1062 /* If we get here when the old symbol is a common symbol, then
1063 we are explicitly letting it override a weak symbol or
1064 function in a dynamic object, and we don't want to warn about
1065 a type change. If the old symbol is a defined symbol, a type
1066 change warning may still be appropriate. */
1068 if (h->root.type == bfd_link_hash_common)
1069 *type_change_ok = TRUE;
1072 /* Handle the special case of an old common symbol merging with a
1073 new symbol which looks like a common symbol in a shared object.
1074 We change *PSEC and *PVALUE to make the new symbol look like a
1075 common symbol, and let _bfd_generic_link_add_one_symbol will do
1076 the right thing. */
1078 if (newdyncommon
1079 && h->root.type == bfd_link_hash_common)
1081 *override = TRUE;
1082 newdef = FALSE;
1083 newdyncommon = FALSE;
1084 *pvalue = sym->st_size;
1085 *psec = sec = bfd_com_section_ptr;
1086 *size_change_ok = TRUE;
1089 /* If the old symbol is from a dynamic object, and the new symbol is
1090 a definition which is not from a dynamic object, then the new
1091 symbol overrides the old symbol. Symbols from regular files
1092 always take precedence over symbols from dynamic objects, even if
1093 they are defined after the dynamic object in the link.
1095 As above, we again permit a common symbol in a regular object to
1096 override a definition in a shared object if the shared object
1097 symbol is a function or is weak. */
1099 flip = NULL;
1100 if (! newdyn
1101 && (newdef
1102 || (bfd_is_com_section (sec)
1103 && (oldweak
1104 || h->type == STT_FUNC)))
1105 && olddyn
1106 && olddef
1107 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
1109 /* Change the hash table entry to undefined, and let
1110 _bfd_generic_link_add_one_symbol do the right thing with the
1111 new definition. */
1113 h->root.type = bfd_link_hash_undefined;
1114 h->root.u.undef.abfd = h->root.u.def.section->owner;
1115 *size_change_ok = TRUE;
1117 olddef = FALSE;
1118 olddyncommon = FALSE;
1120 /* We again permit a type change when a common symbol may be
1121 overriding a function. */
1123 if (bfd_is_com_section (sec))
1124 *type_change_ok = TRUE;
1126 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1127 flip = *sym_hash;
1128 else
1129 /* This union may have been set to be non-NULL when this symbol
1130 was seen in a dynamic object. We must force the union to be
1131 NULL, so that it is correct for a regular symbol. */
1132 h->verinfo.vertree = NULL;
1135 /* Handle the special case of a new common symbol merging with an
1136 old symbol that looks like it might be a common symbol defined in
1137 a shared object. Note that we have already handled the case in
1138 which a new common symbol should simply override the definition
1139 in the shared library. */
1141 if (! newdyn
1142 && bfd_is_com_section (sec)
1143 && olddyncommon)
1145 /* It would be best if we could set the hash table entry to a
1146 common symbol, but we don't know what to use for the section
1147 or the alignment. */
1148 if (! ((*info->callbacks->multiple_common)
1149 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1150 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1151 return FALSE;
1153 /* If the presumed common symbol in the dynamic object is
1154 larger, pretend that the new symbol has its size. */
1156 if (h->size > *pvalue)
1157 *pvalue = h->size;
1159 /* FIXME: We no longer know the alignment required by the symbol
1160 in the dynamic object, so we just wind up using the one from
1161 the regular object. */
1163 olddef = FALSE;
1164 olddyncommon = FALSE;
1166 h->root.type = bfd_link_hash_undefined;
1167 h->root.u.undef.abfd = h->root.u.def.section->owner;
1169 *size_change_ok = TRUE;
1170 *type_change_ok = TRUE;
1172 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1173 flip = *sym_hash;
1174 else
1175 h->verinfo.vertree = NULL;
1178 if (flip != NULL)
1180 /* Handle the case where we had a versioned symbol in a dynamic
1181 library and now find a definition in a normal object. In this
1182 case, we make the versioned symbol point to the normal one. */
1183 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1184 flip->root.type = h->root.type;
1185 h->root.type = bfd_link_hash_indirect;
1186 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1187 (*bed->elf_backend_copy_indirect_symbol) (bed, flip, h);
1188 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1189 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1191 h->elf_link_hash_flags &= ~ELF_LINK_HASH_DEF_DYNAMIC;
1192 flip->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1196 return TRUE;
1199 /* This function is called to create an indirect symbol from the
1200 default for the symbol with the default version if needed. The
1201 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1202 set DYNSYM if the new indirect symbol is dynamic. */
1204 bfd_boolean
1205 _bfd_elf_add_default_symbol (bfd *abfd,
1206 struct bfd_link_info *info,
1207 struct elf_link_hash_entry *h,
1208 const char *name,
1209 Elf_Internal_Sym *sym,
1210 asection **psec,
1211 bfd_vma *value,
1212 bfd_boolean *dynsym,
1213 bfd_boolean override)
1215 bfd_boolean type_change_ok;
1216 bfd_boolean size_change_ok;
1217 bfd_boolean skip;
1218 char *shortname;
1219 struct elf_link_hash_entry *hi;
1220 struct bfd_link_hash_entry *bh;
1221 const struct elf_backend_data *bed;
1222 bfd_boolean collect;
1223 bfd_boolean dynamic;
1224 char *p;
1225 size_t len, shortlen;
1226 asection *sec;
1228 /* If this symbol has a version, and it is the default version, we
1229 create an indirect symbol from the default name to the fully
1230 decorated name. This will cause external references which do not
1231 specify a version to be bound to this version of the symbol. */
1232 p = strchr (name, ELF_VER_CHR);
1233 if (p == NULL || p[1] != ELF_VER_CHR)
1234 return TRUE;
1236 if (override)
1238 /* We are overridden by an old definition. We need to check if we
1239 need to create the indirect symbol from the default name. */
1240 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1241 FALSE, FALSE);
1242 BFD_ASSERT (hi != NULL);
1243 if (hi == h)
1244 return TRUE;
1245 while (hi->root.type == bfd_link_hash_indirect
1246 || hi->root.type == bfd_link_hash_warning)
1248 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1249 if (hi == h)
1250 return TRUE;
1254 bed = get_elf_backend_data (abfd);
1255 collect = bed->collect;
1256 dynamic = (abfd->flags & DYNAMIC) != 0;
1258 shortlen = p - name;
1259 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1260 if (shortname == NULL)
1261 return FALSE;
1262 memcpy (shortname, name, shortlen);
1263 shortname[shortlen] = '\0';
1265 /* We are going to create a new symbol. Merge it with any existing
1266 symbol with this name. For the purposes of the merge, act as
1267 though we were defining the symbol we just defined, although we
1268 actually going to define an indirect symbol. */
1269 type_change_ok = FALSE;
1270 size_change_ok = FALSE;
1271 sec = *psec;
1272 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1273 &hi, &skip, &override, &type_change_ok,
1274 &size_change_ok))
1275 return FALSE;
1277 if (skip)
1278 goto nondefault;
1280 if (! override)
1282 bh = &hi->root;
1283 if (! (_bfd_generic_link_add_one_symbol
1284 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1285 0, name, FALSE, collect, &bh)))
1286 return FALSE;
1287 hi = (struct elf_link_hash_entry *) bh;
1289 else
1291 /* In this case the symbol named SHORTNAME is overriding the
1292 indirect symbol we want to add. We were planning on making
1293 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1294 is the name without a version. NAME is the fully versioned
1295 name, and it is the default version.
1297 Overriding means that we already saw a definition for the
1298 symbol SHORTNAME in a regular object, and it is overriding
1299 the symbol defined in the dynamic object.
1301 When this happens, we actually want to change NAME, the
1302 symbol we just added, to refer to SHORTNAME. This will cause
1303 references to NAME in the shared object to become references
1304 to SHORTNAME in the regular object. This is what we expect
1305 when we override a function in a shared object: that the
1306 references in the shared object will be mapped to the
1307 definition in the regular object. */
1309 while (hi->root.type == bfd_link_hash_indirect
1310 || hi->root.type == bfd_link_hash_warning)
1311 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1313 h->root.type = bfd_link_hash_indirect;
1314 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1315 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1317 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1318 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1319 if (hi->elf_link_hash_flags
1320 & (ELF_LINK_HASH_REF_REGULAR
1321 | ELF_LINK_HASH_DEF_REGULAR))
1323 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1324 return FALSE;
1328 /* Now set HI to H, so that the following code will set the
1329 other fields correctly. */
1330 hi = h;
1333 /* If there is a duplicate definition somewhere, then HI may not
1334 point to an indirect symbol. We will have reported an error to
1335 the user in that case. */
1337 if (hi->root.type == bfd_link_hash_indirect)
1339 struct elf_link_hash_entry *ht;
1341 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1342 (*bed->elf_backend_copy_indirect_symbol) (bed, ht, hi);
1344 /* See if the new flags lead us to realize that the symbol must
1345 be dynamic. */
1346 if (! *dynsym)
1348 if (! dynamic)
1350 if (info->shared
1351 || ((hi->elf_link_hash_flags
1352 & ELF_LINK_HASH_REF_DYNAMIC) != 0))
1353 *dynsym = TRUE;
1355 else
1357 if ((hi->elf_link_hash_flags
1358 & ELF_LINK_HASH_REF_REGULAR) != 0)
1359 *dynsym = TRUE;
1364 /* We also need to define an indirection from the nondefault version
1365 of the symbol. */
1367 nondefault:
1368 len = strlen (name);
1369 shortname = bfd_hash_allocate (&info->hash->table, len);
1370 if (shortname == NULL)
1371 return FALSE;
1372 memcpy (shortname, name, shortlen);
1373 memcpy (shortname + shortlen, p + 1, len - shortlen);
1375 /* Once again, merge with any existing symbol. */
1376 type_change_ok = FALSE;
1377 size_change_ok = FALSE;
1378 sec = *psec;
1379 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1380 &hi, &skip, &override, &type_change_ok,
1381 &size_change_ok))
1382 return FALSE;
1384 if (skip)
1385 return TRUE;
1387 if (override)
1389 /* Here SHORTNAME is a versioned name, so we don't expect to see
1390 the type of override we do in the case above unless it is
1391 overridden by a versioned definition. */
1392 if (hi->root.type != bfd_link_hash_defined
1393 && hi->root.type != bfd_link_hash_defweak)
1394 (*_bfd_error_handler)
1395 (_("%s: warning: unexpected redefinition of indirect versioned symbol `%s'"),
1396 bfd_archive_filename (abfd), shortname);
1398 else
1400 bh = &hi->root;
1401 if (! (_bfd_generic_link_add_one_symbol
1402 (info, abfd, shortname, BSF_INDIRECT,
1403 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1404 return FALSE;
1405 hi = (struct elf_link_hash_entry *) bh;
1407 /* If there is a duplicate definition somewhere, then HI may not
1408 point to an indirect symbol. We will have reported an error
1409 to the user in that case. */
1411 if (hi->root.type == bfd_link_hash_indirect)
1413 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
1415 /* See if the new flags lead us to realize that the symbol
1416 must be dynamic. */
1417 if (! *dynsym)
1419 if (! dynamic)
1421 if (info->shared
1422 || ((hi->elf_link_hash_flags
1423 & ELF_LINK_HASH_REF_DYNAMIC) != 0))
1424 *dynsym = TRUE;
1426 else
1428 if ((hi->elf_link_hash_flags
1429 & ELF_LINK_HASH_REF_REGULAR) != 0)
1430 *dynsym = TRUE;
1436 return TRUE;
1439 /* This routine is used to export all defined symbols into the dynamic
1440 symbol table. It is called via elf_link_hash_traverse. */
1442 bfd_boolean
1443 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1445 struct elf_info_failed *eif = data;
1447 /* Ignore indirect symbols. These are added by the versioning code. */
1448 if (h->root.type == bfd_link_hash_indirect)
1449 return TRUE;
1451 if (h->root.type == bfd_link_hash_warning)
1452 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1454 if (h->dynindx == -1
1455 && (h->elf_link_hash_flags
1456 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
1458 struct bfd_elf_version_tree *t;
1459 struct bfd_elf_version_expr *d;
1461 for (t = eif->verdefs; t != NULL; t = t->next)
1463 if (t->globals.list != NULL)
1465 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1466 if (d != NULL)
1467 goto doit;
1470 if (t->locals.list != NULL)
1472 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1473 if (d != NULL)
1474 return TRUE;
1478 if (!eif->verdefs)
1480 doit:
1481 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1483 eif->failed = TRUE;
1484 return FALSE;
1489 return TRUE;
1492 /* Look through the symbols which are defined in other shared
1493 libraries and referenced here. Update the list of version
1494 dependencies. This will be put into the .gnu.version_r section.
1495 This function is called via elf_link_hash_traverse. */
1497 bfd_boolean
1498 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1499 void *data)
1501 struct elf_find_verdep_info *rinfo = data;
1502 Elf_Internal_Verneed *t;
1503 Elf_Internal_Vernaux *a;
1504 bfd_size_type amt;
1506 if (h->root.type == bfd_link_hash_warning)
1507 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1509 /* We only care about symbols defined in shared objects with version
1510 information. */
1511 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1512 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1513 || h->dynindx == -1
1514 || h->verinfo.verdef == NULL)
1515 return TRUE;
1517 /* See if we already know about this version. */
1518 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1520 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1521 continue;
1523 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1524 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1525 return TRUE;
1527 break;
1530 /* This is a new version. Add it to tree we are building. */
1532 if (t == NULL)
1534 amt = sizeof *t;
1535 t = bfd_zalloc (rinfo->output_bfd, amt);
1536 if (t == NULL)
1538 rinfo->failed = TRUE;
1539 return FALSE;
1542 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1543 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1544 elf_tdata (rinfo->output_bfd)->verref = t;
1547 amt = sizeof *a;
1548 a = bfd_zalloc (rinfo->output_bfd, amt);
1550 /* Note that we are copying a string pointer here, and testing it
1551 above. If bfd_elf_string_from_elf_section is ever changed to
1552 discard the string data when low in memory, this will have to be
1553 fixed. */
1554 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1556 a->vna_flags = h->verinfo.verdef->vd_flags;
1557 a->vna_nextptr = t->vn_auxptr;
1559 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1560 ++rinfo->vers;
1562 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1564 t->vn_auxptr = a;
1566 return TRUE;
1569 /* Figure out appropriate versions for all the symbols. We may not
1570 have the version number script until we have read all of the input
1571 files, so until that point we don't know which symbols should be
1572 local. This function is called via elf_link_hash_traverse. */
1574 bfd_boolean
1575 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1577 struct elf_assign_sym_version_info *sinfo;
1578 struct bfd_link_info *info;
1579 const struct elf_backend_data *bed;
1580 struct elf_info_failed eif;
1581 char *p;
1582 bfd_size_type amt;
1584 sinfo = data;
1585 info = sinfo->info;
1587 if (h->root.type == bfd_link_hash_warning)
1588 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1590 /* Fix the symbol flags. */
1591 eif.failed = FALSE;
1592 eif.info = info;
1593 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1595 if (eif.failed)
1596 sinfo->failed = TRUE;
1597 return FALSE;
1600 /* We only need version numbers for symbols defined in regular
1601 objects. */
1602 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1603 return TRUE;
1605 bed = get_elf_backend_data (sinfo->output_bfd);
1606 p = strchr (h->root.root.string, ELF_VER_CHR);
1607 if (p != NULL && h->verinfo.vertree == NULL)
1609 struct bfd_elf_version_tree *t;
1610 bfd_boolean hidden;
1612 hidden = TRUE;
1614 /* There are two consecutive ELF_VER_CHR characters if this is
1615 not a hidden symbol. */
1616 ++p;
1617 if (*p == ELF_VER_CHR)
1619 hidden = FALSE;
1620 ++p;
1623 /* If there is no version string, we can just return out. */
1624 if (*p == '\0')
1626 if (hidden)
1627 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
1628 return TRUE;
1631 /* Look for the version. If we find it, it is no longer weak. */
1632 for (t = sinfo->verdefs; t != NULL; t = t->next)
1634 if (strcmp (t->name, p) == 0)
1636 size_t len;
1637 char *alc;
1638 struct bfd_elf_version_expr *d;
1640 len = p - h->root.root.string;
1641 alc = bfd_malloc (len);
1642 if (alc == NULL)
1643 return FALSE;
1644 memcpy (alc, h->root.root.string, len - 1);
1645 alc[len - 1] = '\0';
1646 if (alc[len - 2] == ELF_VER_CHR)
1647 alc[len - 2] = '\0';
1649 h->verinfo.vertree = t;
1650 t->used = TRUE;
1651 d = NULL;
1653 if (t->globals.list != NULL)
1654 d = (*t->match) (&t->globals, NULL, alc);
1656 /* See if there is anything to force this symbol to
1657 local scope. */
1658 if (d == NULL && t->locals.list != NULL)
1660 d = (*t->match) (&t->locals, NULL, alc);
1661 if (d != NULL
1662 && h->dynindx != -1
1663 && info->shared
1664 && ! info->export_dynamic)
1665 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1668 free (alc);
1669 break;
1673 /* If we are building an application, we need to create a
1674 version node for this version. */
1675 if (t == NULL && info->executable)
1677 struct bfd_elf_version_tree **pp;
1678 int version_index;
1680 /* If we aren't going to export this symbol, we don't need
1681 to worry about it. */
1682 if (h->dynindx == -1)
1683 return TRUE;
1685 amt = sizeof *t;
1686 t = bfd_zalloc (sinfo->output_bfd, amt);
1687 if (t == NULL)
1689 sinfo->failed = TRUE;
1690 return FALSE;
1693 t->name = p;
1694 t->name_indx = (unsigned int) -1;
1695 t->used = TRUE;
1697 version_index = 1;
1698 /* Don't count anonymous version tag. */
1699 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1700 version_index = 0;
1701 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1702 ++version_index;
1703 t->vernum = version_index;
1705 *pp = t;
1707 h->verinfo.vertree = t;
1709 else if (t == NULL)
1711 /* We could not find the version for a symbol when
1712 generating a shared archive. Return an error. */
1713 (*_bfd_error_handler)
1714 (_("%s: undefined versioned symbol name %s"),
1715 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
1716 bfd_set_error (bfd_error_bad_value);
1717 sinfo->failed = TRUE;
1718 return FALSE;
1721 if (hidden)
1722 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
1725 /* If we don't have a version for this symbol, see if we can find
1726 something. */
1727 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1729 struct bfd_elf_version_tree *t;
1730 struct bfd_elf_version_tree *local_ver;
1731 struct bfd_elf_version_expr *d;
1733 /* See if can find what version this symbol is in. If the
1734 symbol is supposed to be local, then don't actually register
1735 it. */
1736 local_ver = NULL;
1737 for (t = sinfo->verdefs; t != NULL; t = t->next)
1739 if (t->globals.list != NULL)
1741 bfd_boolean matched;
1743 matched = FALSE;
1744 d = NULL;
1745 while ((d = (*t->match) (&t->globals, d,
1746 h->root.root.string)) != NULL)
1747 if (d->symver)
1748 matched = TRUE;
1749 else
1751 /* There is a version without definition. Make
1752 the symbol the default definition for this
1753 version. */
1754 h->verinfo.vertree = t;
1755 local_ver = NULL;
1756 d->script = 1;
1757 break;
1759 if (d != NULL)
1760 break;
1761 else if (matched)
1762 /* There is no undefined version for this symbol. Hide the
1763 default one. */
1764 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1767 if (t->locals.list != NULL)
1769 d = NULL;
1770 while ((d = (*t->match) (&t->locals, d,
1771 h->root.root.string)) != NULL)
1773 local_ver = t;
1774 /* If the match is "*", keep looking for a more
1775 explicit, perhaps even global, match.
1776 XXX: Shouldn't this be !d->wildcard instead? */
1777 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1778 break;
1781 if (d != NULL)
1782 break;
1786 if (local_ver != NULL)
1788 h->verinfo.vertree = local_ver;
1789 if (h->dynindx != -1
1790 && info->shared
1791 && ! info->export_dynamic)
1793 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1798 return TRUE;
1801 /* Read and swap the relocs from the section indicated by SHDR. This
1802 may be either a REL or a RELA section. The relocations are
1803 translated into RELA relocations and stored in INTERNAL_RELOCS,
1804 which should have already been allocated to contain enough space.
1805 The EXTERNAL_RELOCS are a buffer where the external form of the
1806 relocations should be stored.
1808 Returns FALSE if something goes wrong. */
1810 static bfd_boolean
1811 elf_link_read_relocs_from_section (bfd *abfd,
1812 asection *sec,
1813 Elf_Internal_Shdr *shdr,
1814 void *external_relocs,
1815 Elf_Internal_Rela *internal_relocs)
1817 const struct elf_backend_data *bed;
1818 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1819 const bfd_byte *erela;
1820 const bfd_byte *erelaend;
1821 Elf_Internal_Rela *irela;
1822 Elf_Internal_Shdr *symtab_hdr;
1823 size_t nsyms;
1825 /* Position ourselves at the start of the section. */
1826 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1827 return FALSE;
1829 /* Read the relocations. */
1830 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1831 return FALSE;
1833 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1834 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1836 bed = get_elf_backend_data (abfd);
1838 /* Convert the external relocations to the internal format. */
1839 if (shdr->sh_entsize == bed->s->sizeof_rel)
1840 swap_in = bed->s->swap_reloc_in;
1841 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1842 swap_in = bed->s->swap_reloca_in;
1843 else
1845 bfd_set_error (bfd_error_wrong_format);
1846 return FALSE;
1849 erela = external_relocs;
1850 erelaend = erela + shdr->sh_size;
1851 irela = internal_relocs;
1852 while (erela < erelaend)
1854 bfd_vma r_symndx;
1856 (*swap_in) (abfd, erela, irela);
1857 r_symndx = ELF32_R_SYM (irela->r_info);
1858 if (bed->s->arch_size == 64)
1859 r_symndx >>= 24;
1860 if ((size_t) r_symndx >= nsyms)
1862 char *sec_name = bfd_get_section_ident (sec);
1863 (*_bfd_error_handler)
1864 (_("%s: bad reloc symbol index (0x%lx >= 0x%lx) for offset 0x%lx in section `%s'"),
1865 bfd_archive_filename (abfd), (unsigned long) r_symndx,
1866 (unsigned long) nsyms, irela->r_offset,
1867 sec_name ? sec_name : sec->name);
1868 if (sec_name)
1869 free (sec_name);
1870 bfd_set_error (bfd_error_bad_value);
1871 return FALSE;
1873 irela += bed->s->int_rels_per_ext_rel;
1874 erela += shdr->sh_entsize;
1877 return TRUE;
1880 /* Read and swap the relocs for a section O. They may have been
1881 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
1882 not NULL, they are used as buffers to read into. They are known to
1883 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
1884 the return value is allocated using either malloc or bfd_alloc,
1885 according to the KEEP_MEMORY argument. If O has two relocation
1886 sections (both REL and RELA relocations), then the REL_HDR
1887 relocations will appear first in INTERNAL_RELOCS, followed by the
1888 REL_HDR2 relocations. */
1890 Elf_Internal_Rela *
1891 _bfd_elf_link_read_relocs (bfd *abfd,
1892 asection *o,
1893 void *external_relocs,
1894 Elf_Internal_Rela *internal_relocs,
1895 bfd_boolean keep_memory)
1897 Elf_Internal_Shdr *rel_hdr;
1898 void *alloc1 = NULL;
1899 Elf_Internal_Rela *alloc2 = NULL;
1900 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1902 if (elf_section_data (o)->relocs != NULL)
1903 return elf_section_data (o)->relocs;
1905 if (o->reloc_count == 0)
1906 return NULL;
1908 rel_hdr = &elf_section_data (o)->rel_hdr;
1910 if (internal_relocs == NULL)
1912 bfd_size_type size;
1914 size = o->reloc_count;
1915 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
1916 if (keep_memory)
1917 internal_relocs = bfd_alloc (abfd, size);
1918 else
1919 internal_relocs = alloc2 = bfd_malloc (size);
1920 if (internal_relocs == NULL)
1921 goto error_return;
1924 if (external_relocs == NULL)
1926 bfd_size_type size = rel_hdr->sh_size;
1928 if (elf_section_data (o)->rel_hdr2)
1929 size += elf_section_data (o)->rel_hdr2->sh_size;
1930 alloc1 = bfd_malloc (size);
1931 if (alloc1 == NULL)
1932 goto error_return;
1933 external_relocs = alloc1;
1936 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
1937 external_relocs,
1938 internal_relocs))
1939 goto error_return;
1940 if (elf_section_data (o)->rel_hdr2
1941 && (!elf_link_read_relocs_from_section
1942 (abfd, o,
1943 elf_section_data (o)->rel_hdr2,
1944 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
1945 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
1946 * bed->s->int_rels_per_ext_rel))))
1947 goto error_return;
1949 /* Cache the results for next time, if we can. */
1950 if (keep_memory)
1951 elf_section_data (o)->relocs = internal_relocs;
1953 if (alloc1 != NULL)
1954 free (alloc1);
1956 /* Don't free alloc2, since if it was allocated we are passing it
1957 back (under the name of internal_relocs). */
1959 return internal_relocs;
1961 error_return:
1962 if (alloc1 != NULL)
1963 free (alloc1);
1964 if (alloc2 != NULL)
1965 free (alloc2);
1966 return NULL;
1969 /* Compute the size of, and allocate space for, REL_HDR which is the
1970 section header for a section containing relocations for O. */
1972 bfd_boolean
1973 _bfd_elf_link_size_reloc_section (bfd *abfd,
1974 Elf_Internal_Shdr *rel_hdr,
1975 asection *o)
1977 bfd_size_type reloc_count;
1978 bfd_size_type num_rel_hashes;
1980 /* Figure out how many relocations there will be. */
1981 if (rel_hdr == &elf_section_data (o)->rel_hdr)
1982 reloc_count = elf_section_data (o)->rel_count;
1983 else
1984 reloc_count = elf_section_data (o)->rel_count2;
1986 num_rel_hashes = o->reloc_count;
1987 if (num_rel_hashes < reloc_count)
1988 num_rel_hashes = reloc_count;
1990 /* That allows us to calculate the size of the section. */
1991 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
1993 /* The contents field must last into write_object_contents, so we
1994 allocate it with bfd_alloc rather than malloc. Also since we
1995 cannot be sure that the contents will actually be filled in,
1996 we zero the allocated space. */
1997 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
1998 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
1999 return FALSE;
2001 /* We only allocate one set of hash entries, so we only do it the
2002 first time we are called. */
2003 if (elf_section_data (o)->rel_hashes == NULL
2004 && num_rel_hashes)
2006 struct elf_link_hash_entry **p;
2008 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2009 if (p == NULL)
2010 return FALSE;
2012 elf_section_data (o)->rel_hashes = p;
2015 return TRUE;
2018 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2019 originated from the section given by INPUT_REL_HDR) to the
2020 OUTPUT_BFD. */
2022 bfd_boolean
2023 _bfd_elf_link_output_relocs (bfd *output_bfd,
2024 asection *input_section,
2025 Elf_Internal_Shdr *input_rel_hdr,
2026 Elf_Internal_Rela *internal_relocs)
2028 Elf_Internal_Rela *irela;
2029 Elf_Internal_Rela *irelaend;
2030 bfd_byte *erel;
2031 Elf_Internal_Shdr *output_rel_hdr;
2032 asection *output_section;
2033 unsigned int *rel_countp = NULL;
2034 const struct elf_backend_data *bed;
2035 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2037 output_section = input_section->output_section;
2038 output_rel_hdr = NULL;
2040 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2041 == input_rel_hdr->sh_entsize)
2043 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2044 rel_countp = &elf_section_data (output_section)->rel_count;
2046 else if (elf_section_data (output_section)->rel_hdr2
2047 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2048 == input_rel_hdr->sh_entsize))
2050 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2051 rel_countp = &elf_section_data (output_section)->rel_count2;
2053 else
2055 char *sec_name = bfd_get_section_ident (input_section);
2056 (*_bfd_error_handler)
2057 (_("%s: relocation size mismatch in %s section %s"),
2058 bfd_get_filename (output_bfd),
2059 bfd_archive_filename (input_section->owner),
2060 sec_name ? sec_name : input_section->name);
2061 if (sec_name)
2062 free (sec_name);
2063 bfd_set_error (bfd_error_wrong_object_format);
2064 return FALSE;
2067 bed = get_elf_backend_data (output_bfd);
2068 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2069 swap_out = bed->s->swap_reloc_out;
2070 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2071 swap_out = bed->s->swap_reloca_out;
2072 else
2073 abort ();
2075 erel = output_rel_hdr->contents;
2076 erel += *rel_countp * input_rel_hdr->sh_entsize;
2077 irela = internal_relocs;
2078 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2079 * bed->s->int_rels_per_ext_rel);
2080 while (irela < irelaend)
2082 (*swap_out) (output_bfd, irela, erel);
2083 irela += bed->s->int_rels_per_ext_rel;
2084 erel += input_rel_hdr->sh_entsize;
2087 /* Bump the counter, so that we know where to add the next set of
2088 relocations. */
2089 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2091 return TRUE;
2094 /* Fix up the flags for a symbol. This handles various cases which
2095 can only be fixed after all the input files are seen. This is
2096 currently called by both adjust_dynamic_symbol and
2097 assign_sym_version, which is unnecessary but perhaps more robust in
2098 the face of future changes. */
2100 bfd_boolean
2101 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2102 struct elf_info_failed *eif)
2104 /* If this symbol was mentioned in a non-ELF file, try to set
2105 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2106 permit a non-ELF file to correctly refer to a symbol defined in
2107 an ELF dynamic object. */
2108 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
2110 while (h->root.type == bfd_link_hash_indirect)
2111 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2113 if (h->root.type != bfd_link_hash_defined
2114 && h->root.type != bfd_link_hash_defweak)
2115 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
2116 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
2117 else
2119 if (h->root.u.def.section->owner != NULL
2120 && (bfd_get_flavour (h->root.u.def.section->owner)
2121 == bfd_target_elf_flavour))
2122 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
2123 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
2124 else
2125 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2128 if (h->dynindx == -1
2129 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2130 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
2132 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2134 eif->failed = TRUE;
2135 return FALSE;
2139 else
2141 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
2142 was first seen in a non-ELF file. Fortunately, if the symbol
2143 was first seen in an ELF file, we're probably OK unless the
2144 symbol was defined in a non-ELF file. Catch that case here.
2145 FIXME: We're still in trouble if the symbol was first seen in
2146 a dynamic object, and then later in a non-ELF regular object. */
2147 if ((h->root.type == bfd_link_hash_defined
2148 || h->root.type == bfd_link_hash_defweak)
2149 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
2150 && (h->root.u.def.section->owner != NULL
2151 ? (bfd_get_flavour (h->root.u.def.section->owner)
2152 != bfd_target_elf_flavour)
2153 : (bfd_is_abs_section (h->root.u.def.section)
2154 && (h->elf_link_hash_flags
2155 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
2156 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2159 /* If this is a final link, and the symbol was defined as a common
2160 symbol in a regular object file, and there was no definition in
2161 any dynamic object, then the linker will have allocated space for
2162 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
2163 flag will not have been set. */
2164 if (h->root.type == bfd_link_hash_defined
2165 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
2166 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
2167 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2168 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2169 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2171 /* If -Bsymbolic was used (which means to bind references to global
2172 symbols to the definition within the shared object), and this
2173 symbol was defined in a regular object, then it actually doesn't
2174 need a PLT entry. Likewise, if the symbol has non-default
2175 visibility. If the symbol has hidden or internal visibility, we
2176 will force it local. */
2177 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
2178 && eif->info->shared
2179 && is_elf_hash_table (eif->info->hash)
2180 && (eif->info->symbolic
2181 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2182 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2184 const struct elf_backend_data *bed;
2185 bfd_boolean force_local;
2187 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2189 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2190 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2191 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2194 /* If a weak undefined symbol has non-default visibility, we also
2195 hide it from the dynamic linker. */
2196 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2197 && h->root.type == bfd_link_hash_undefweak)
2199 const struct elf_backend_data *bed;
2200 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2201 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2204 /* If this is a weak defined symbol in a dynamic object, and we know
2205 the real definition in the dynamic object, copy interesting flags
2206 over to the real definition. */
2207 if (h->weakdef != NULL)
2209 struct elf_link_hash_entry *weakdef;
2211 weakdef = h->weakdef;
2212 if (h->root.type == bfd_link_hash_indirect)
2213 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2215 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2216 || h->root.type == bfd_link_hash_defweak);
2217 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2218 || weakdef->root.type == bfd_link_hash_defweak);
2219 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
2221 /* If the real definition is defined by a regular object file,
2222 don't do anything special. See the longer description in
2223 _bfd_elf_adjust_dynamic_symbol, below. */
2224 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
2225 h->weakdef = NULL;
2226 else
2228 const struct elf_backend_data *bed;
2230 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2231 (*bed->elf_backend_copy_indirect_symbol) (bed, weakdef, h);
2235 return TRUE;
2238 /* Make the backend pick a good value for a dynamic symbol. This is
2239 called via elf_link_hash_traverse, and also calls itself
2240 recursively. */
2242 bfd_boolean
2243 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2245 struct elf_info_failed *eif = data;
2246 bfd *dynobj;
2247 const struct elf_backend_data *bed;
2249 if (! is_elf_hash_table (eif->info->hash))
2250 return FALSE;
2252 if (h->root.type == bfd_link_hash_warning)
2254 h->plt = elf_hash_table (eif->info)->init_offset;
2255 h->got = elf_hash_table (eif->info)->init_offset;
2257 /* When warning symbols are created, they **replace** the "real"
2258 entry in the hash table, thus we never get to see the real
2259 symbol in a hash traversal. So look at it now. */
2260 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2263 /* Ignore indirect symbols. These are added by the versioning code. */
2264 if (h->root.type == bfd_link_hash_indirect)
2265 return TRUE;
2267 /* Fix the symbol flags. */
2268 if (! _bfd_elf_fix_symbol_flags (h, eif))
2269 return FALSE;
2271 /* If this symbol does not require a PLT entry, and it is not
2272 defined by a dynamic object, or is not referenced by a regular
2273 object, ignore it. We do have to handle a weak defined symbol,
2274 even if no regular object refers to it, if we decided to add it
2275 to the dynamic symbol table. FIXME: Do we normally need to worry
2276 about symbols which are defined by one dynamic object and
2277 referenced by another one? */
2278 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
2279 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
2280 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
2281 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
2282 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
2284 h->plt = elf_hash_table (eif->info)->init_offset;
2285 return TRUE;
2288 /* If we've already adjusted this symbol, don't do it again. This
2289 can happen via a recursive call. */
2290 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
2291 return TRUE;
2293 /* Don't look at this symbol again. Note that we must set this
2294 after checking the above conditions, because we may look at a
2295 symbol once, decide not to do anything, and then get called
2296 recursively later after REF_REGULAR is set below. */
2297 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
2299 /* If this is a weak definition, and we know a real definition, and
2300 the real symbol is not itself defined by a regular object file,
2301 then get a good value for the real definition. We handle the
2302 real symbol first, for the convenience of the backend routine.
2304 Note that there is a confusing case here. If the real definition
2305 is defined by a regular object file, we don't get the real symbol
2306 from the dynamic object, but we do get the weak symbol. If the
2307 processor backend uses a COPY reloc, then if some routine in the
2308 dynamic object changes the real symbol, we will not see that
2309 change in the corresponding weak symbol. This is the way other
2310 ELF linkers work as well, and seems to be a result of the shared
2311 library model.
2313 I will clarify this issue. Most SVR4 shared libraries define the
2314 variable _timezone and define timezone as a weak synonym. The
2315 tzset call changes _timezone. If you write
2316 extern int timezone;
2317 int _timezone = 5;
2318 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2319 you might expect that, since timezone is a synonym for _timezone,
2320 the same number will print both times. However, if the processor
2321 backend uses a COPY reloc, then actually timezone will be copied
2322 into your process image, and, since you define _timezone
2323 yourself, _timezone will not. Thus timezone and _timezone will
2324 wind up at different memory locations. The tzset call will set
2325 _timezone, leaving timezone unchanged. */
2327 if (h->weakdef != NULL)
2329 /* If we get to this point, we know there is an implicit
2330 reference by a regular object file via the weak symbol H.
2331 FIXME: Is this really true? What if the traversal finds
2332 H->WEAKDEF before it finds H? */
2333 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
2335 if (! _bfd_elf_adjust_dynamic_symbol (h->weakdef, eif))
2336 return FALSE;
2339 /* If a symbol has no type and no size and does not require a PLT
2340 entry, then we are probably about to do the wrong thing here: we
2341 are probably going to create a COPY reloc for an empty object.
2342 This case can arise when a shared object is built with assembly
2343 code, and the assembly code fails to set the symbol type. */
2344 if (h->size == 0
2345 && h->type == STT_NOTYPE
2346 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
2347 (*_bfd_error_handler)
2348 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2349 h->root.root.string);
2351 dynobj = elf_hash_table (eif->info)->dynobj;
2352 bed = get_elf_backend_data (dynobj);
2353 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2355 eif->failed = TRUE;
2356 return FALSE;
2359 return TRUE;
2362 /* Adjust all external symbols pointing into SEC_MERGE sections
2363 to reflect the object merging within the sections. */
2365 bfd_boolean
2366 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2368 asection *sec;
2370 if (h->root.type == bfd_link_hash_warning)
2371 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2373 if ((h->root.type == bfd_link_hash_defined
2374 || h->root.type == bfd_link_hash_defweak)
2375 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2376 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2378 bfd *output_bfd = data;
2380 h->root.u.def.value =
2381 _bfd_merged_section_offset (output_bfd,
2382 &h->root.u.def.section,
2383 elf_section_data (sec)->sec_info,
2384 h->root.u.def.value);
2387 return TRUE;
2390 /* Returns false if the symbol referred to by H should be considered
2391 to resolve local to the current module, and true if it should be
2392 considered to bind dynamically. */
2394 bfd_boolean
2395 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2396 struct bfd_link_info *info,
2397 bfd_boolean ignore_protected)
2399 bfd_boolean binding_stays_local_p;
2401 if (h == NULL)
2402 return FALSE;
2404 while (h->root.type == bfd_link_hash_indirect
2405 || h->root.type == bfd_link_hash_warning)
2406 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2408 /* If it was forced local, then clearly it's not dynamic. */
2409 if (h->dynindx == -1)
2410 return FALSE;
2411 if (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL)
2412 return FALSE;
2414 /* Identify the cases where name binding rules say that a
2415 visible symbol resolves locally. */
2416 binding_stays_local_p = info->executable || info->symbolic;
2418 switch (ELF_ST_VISIBILITY (h->other))
2420 case STV_INTERNAL:
2421 case STV_HIDDEN:
2422 return FALSE;
2424 case STV_PROTECTED:
2425 /* Proper resolution for function pointer equality may require
2426 that these symbols perhaps be resolved dynamically, even though
2427 we should be resolving them to the current module. */
2428 if (!ignore_protected)
2429 binding_stays_local_p = TRUE;
2430 break;
2432 default:
2433 break;
2436 /* If it isn't defined locally, then clearly it's dynamic. */
2437 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2438 return TRUE;
2440 /* Otherwise, the symbol is dynamic if binding rules don't tell
2441 us that it remains local. */
2442 return !binding_stays_local_p;
2445 /* Return true if the symbol referred to by H should be considered
2446 to resolve local to the current module, and false otherwise. Differs
2447 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2448 undefined symbols and weak symbols. */
2450 bfd_boolean
2451 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2452 struct bfd_link_info *info,
2453 bfd_boolean local_protected)
2455 /* If it's a local sym, of course we resolve locally. */
2456 if (h == NULL)
2457 return TRUE;
2459 /* Common symbols that become definitions don't get the DEF_REGULAR
2460 flag set, so test it first, and don't bail out. */
2461 if (ELF_COMMON_DEF_P (h))
2462 /* Do nothing. */;
2463 /* If we don't have a definition in a regular file, then we can't
2464 resolve locally. The sym is either undefined or dynamic. */
2465 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2466 return FALSE;
2468 /* Forced local symbols resolve locally. */
2469 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
2470 return TRUE;
2472 /* As do non-dynamic symbols. */
2473 if (h->dynindx == -1)
2474 return TRUE;
2476 /* At this point, we know the symbol is defined and dynamic. In an
2477 executable it must resolve locally, likewise when building symbolic
2478 shared libraries. */
2479 if (info->executable || info->symbolic)
2480 return TRUE;
2482 /* Now deal with defined dynamic symbols in shared libraries. Ones
2483 with default visibility might not resolve locally. */
2484 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2485 return FALSE;
2487 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2488 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2489 return TRUE;
2491 /* Function pointer equality tests may require that STV_PROTECTED
2492 symbols be treated as dynamic symbols, even when we know that the
2493 dynamic linker will resolve them locally. */
2494 return local_protected;
2497 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2498 aligned. Returns the first TLS output section. */
2500 struct bfd_section *
2501 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2503 struct bfd_section *sec, *tls;
2504 unsigned int align = 0;
2506 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2507 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2508 break;
2509 tls = sec;
2511 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2512 if (sec->alignment_power > align)
2513 align = sec->alignment_power;
2515 elf_hash_table (info)->tls_sec = tls;
2517 /* Ensure the alignment of the first section is the largest alignment,
2518 so that the tls segment starts aligned. */
2519 if (tls != NULL)
2520 tls->alignment_power = align;
2522 return tls;
2525 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2526 static bfd_boolean
2527 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2528 Elf_Internal_Sym *sym)
2530 /* Local symbols do not count, but target specific ones might. */
2531 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2532 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2533 return FALSE;
2535 /* Function symbols do not count. */
2536 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2537 return FALSE;
2539 /* If the section is undefined, then so is the symbol. */
2540 if (sym->st_shndx == SHN_UNDEF)
2541 return FALSE;
2543 /* If the symbol is defined in the common section, then
2544 it is a common definition and so does not count. */
2545 if (sym->st_shndx == SHN_COMMON)
2546 return FALSE;
2548 /* If the symbol is in a target specific section then we
2549 must rely upon the backend to tell us what it is. */
2550 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2551 /* FIXME - this function is not coded yet:
2553 return _bfd_is_global_symbol_definition (abfd, sym);
2555 Instead for now assume that the definition is not global,
2556 Even if this is wrong, at least the linker will behave
2557 in the same way that it used to do. */
2558 return FALSE;
2560 return TRUE;
2563 /* Search the symbol table of the archive element of the archive ABFD
2564 whose archive map contains a mention of SYMDEF, and determine if
2565 the symbol is defined in this element. */
2566 static bfd_boolean
2567 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2569 Elf_Internal_Shdr * hdr;
2570 bfd_size_type symcount;
2571 bfd_size_type extsymcount;
2572 bfd_size_type extsymoff;
2573 Elf_Internal_Sym *isymbuf;
2574 Elf_Internal_Sym *isym;
2575 Elf_Internal_Sym *isymend;
2576 bfd_boolean result;
2578 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2579 if (abfd == NULL)
2580 return FALSE;
2582 if (! bfd_check_format (abfd, bfd_object))
2583 return FALSE;
2585 /* If we have already included the element containing this symbol in the
2586 link then we do not need to include it again. Just claim that any symbol
2587 it contains is not a definition, so that our caller will not decide to
2588 (re)include this element. */
2589 if (abfd->archive_pass)
2590 return FALSE;
2592 /* Select the appropriate symbol table. */
2593 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2594 hdr = &elf_tdata (abfd)->symtab_hdr;
2595 else
2596 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2598 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2600 /* The sh_info field of the symtab header tells us where the
2601 external symbols start. We don't care about the local symbols. */
2602 if (elf_bad_symtab (abfd))
2604 extsymcount = symcount;
2605 extsymoff = 0;
2607 else
2609 extsymcount = symcount - hdr->sh_info;
2610 extsymoff = hdr->sh_info;
2613 if (extsymcount == 0)
2614 return FALSE;
2616 /* Read in the symbol table. */
2617 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2618 NULL, NULL, NULL);
2619 if (isymbuf == NULL)
2620 return FALSE;
2622 /* Scan the symbol table looking for SYMDEF. */
2623 result = FALSE;
2624 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2626 const char *name;
2628 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2629 isym->st_name);
2630 if (name == NULL)
2631 break;
2633 if (strcmp (name, symdef->name) == 0)
2635 result = is_global_data_symbol_definition (abfd, isym);
2636 break;
2640 free (isymbuf);
2642 return result;
2645 /* Add an entry to the .dynamic table. */
2647 bfd_boolean
2648 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2649 bfd_vma tag,
2650 bfd_vma val)
2652 struct elf_link_hash_table *hash_table;
2653 const struct elf_backend_data *bed;
2654 asection *s;
2655 bfd_size_type newsize;
2656 bfd_byte *newcontents;
2657 Elf_Internal_Dyn dyn;
2659 hash_table = elf_hash_table (info);
2660 if (! is_elf_hash_table (hash_table))
2661 return FALSE;
2663 bed = get_elf_backend_data (hash_table->dynobj);
2664 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2665 BFD_ASSERT (s != NULL);
2667 newsize = s->size + bed->s->sizeof_dyn;
2668 newcontents = bfd_realloc (s->contents, newsize);
2669 if (newcontents == NULL)
2670 return FALSE;
2672 dyn.d_tag = tag;
2673 dyn.d_un.d_val = val;
2674 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2676 s->size = newsize;
2677 s->contents = newcontents;
2679 return TRUE;
2682 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2683 otherwise just check whether one already exists. Returns -1 on error,
2684 1 if a DT_NEEDED tag already exists, and 0 on success. */
2686 static int
2687 elf_add_dt_needed_tag (struct bfd_link_info *info,
2688 const char *soname,
2689 bfd_boolean do_it)
2691 struct elf_link_hash_table *hash_table;
2692 bfd_size_type oldsize;
2693 bfd_size_type strindex;
2695 hash_table = elf_hash_table (info);
2696 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2697 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2698 if (strindex == (bfd_size_type) -1)
2699 return -1;
2701 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2703 asection *sdyn;
2704 const struct elf_backend_data *bed;
2705 bfd_byte *extdyn;
2707 bed = get_elf_backend_data (hash_table->dynobj);
2708 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2709 BFD_ASSERT (sdyn != NULL);
2711 for (extdyn = sdyn->contents;
2712 extdyn < sdyn->contents + sdyn->size;
2713 extdyn += bed->s->sizeof_dyn)
2715 Elf_Internal_Dyn dyn;
2717 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2718 if (dyn.d_tag == DT_NEEDED
2719 && dyn.d_un.d_val == strindex)
2721 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2722 return 1;
2727 if (do_it)
2729 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2730 return -1;
2732 else
2733 /* We were just checking for existence of the tag. */
2734 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2736 return 0;
2739 /* Sort symbol by value and section. */
2740 static int
2741 elf_sort_symbol (const void *arg1, const void *arg2)
2743 const struct elf_link_hash_entry *h1;
2744 const struct elf_link_hash_entry *h2;
2745 bfd_signed_vma vdiff;
2747 h1 = *(const struct elf_link_hash_entry **) arg1;
2748 h2 = *(const struct elf_link_hash_entry **) arg2;
2749 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2750 if (vdiff != 0)
2751 return vdiff > 0 ? 1 : -1;
2752 else
2754 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2755 if (sdiff != 0)
2756 return sdiff > 0 ? 1 : -1;
2758 return 0;
2761 /* This function is used to adjust offsets into .dynstr for
2762 dynamic symbols. This is called via elf_link_hash_traverse. */
2764 static bfd_boolean
2765 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
2767 struct elf_strtab_hash *dynstr = data;
2769 if (h->root.type == bfd_link_hash_warning)
2770 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2772 if (h->dynindx != -1)
2773 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
2774 return TRUE;
2777 /* Assign string offsets in .dynstr, update all structures referencing
2778 them. */
2780 static bfd_boolean
2781 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
2783 struct elf_link_hash_table *hash_table = elf_hash_table (info);
2784 struct elf_link_local_dynamic_entry *entry;
2785 struct elf_strtab_hash *dynstr = hash_table->dynstr;
2786 bfd *dynobj = hash_table->dynobj;
2787 asection *sdyn;
2788 bfd_size_type size;
2789 const struct elf_backend_data *bed;
2790 bfd_byte *extdyn;
2792 _bfd_elf_strtab_finalize (dynstr);
2793 size = _bfd_elf_strtab_size (dynstr);
2795 bed = get_elf_backend_data (dynobj);
2796 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2797 BFD_ASSERT (sdyn != NULL);
2799 /* Update all .dynamic entries referencing .dynstr strings. */
2800 for (extdyn = sdyn->contents;
2801 extdyn < sdyn->contents + sdyn->size;
2802 extdyn += bed->s->sizeof_dyn)
2804 Elf_Internal_Dyn dyn;
2806 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
2807 switch (dyn.d_tag)
2809 case DT_STRSZ:
2810 dyn.d_un.d_val = size;
2811 break;
2812 case DT_NEEDED:
2813 case DT_SONAME:
2814 case DT_RPATH:
2815 case DT_RUNPATH:
2816 case DT_FILTER:
2817 case DT_AUXILIARY:
2818 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
2819 break;
2820 default:
2821 continue;
2823 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
2826 /* Now update local dynamic symbols. */
2827 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
2828 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
2829 entry->isym.st_name);
2831 /* And the rest of dynamic symbols. */
2832 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
2834 /* Adjust version definitions. */
2835 if (elf_tdata (output_bfd)->cverdefs)
2837 asection *s;
2838 bfd_byte *p;
2839 bfd_size_type i;
2840 Elf_Internal_Verdef def;
2841 Elf_Internal_Verdaux defaux;
2843 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2844 p = s->contents;
2847 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
2848 &def);
2849 p += sizeof (Elf_External_Verdef);
2850 for (i = 0; i < def.vd_cnt; ++i)
2852 _bfd_elf_swap_verdaux_in (output_bfd,
2853 (Elf_External_Verdaux *) p, &defaux);
2854 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
2855 defaux.vda_name);
2856 _bfd_elf_swap_verdaux_out (output_bfd,
2857 &defaux, (Elf_External_Verdaux *) p);
2858 p += sizeof (Elf_External_Verdaux);
2861 while (def.vd_next);
2864 /* Adjust version references. */
2865 if (elf_tdata (output_bfd)->verref)
2867 asection *s;
2868 bfd_byte *p;
2869 bfd_size_type i;
2870 Elf_Internal_Verneed need;
2871 Elf_Internal_Vernaux needaux;
2873 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
2874 p = s->contents;
2877 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
2878 &need);
2879 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
2880 _bfd_elf_swap_verneed_out (output_bfd, &need,
2881 (Elf_External_Verneed *) p);
2882 p += sizeof (Elf_External_Verneed);
2883 for (i = 0; i < need.vn_cnt; ++i)
2885 _bfd_elf_swap_vernaux_in (output_bfd,
2886 (Elf_External_Vernaux *) p, &needaux);
2887 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
2888 needaux.vna_name);
2889 _bfd_elf_swap_vernaux_out (output_bfd,
2890 &needaux,
2891 (Elf_External_Vernaux *) p);
2892 p += sizeof (Elf_External_Vernaux);
2895 while (need.vn_next);
2898 return TRUE;
2901 /* Add symbols from an ELF object file to the linker hash table. */
2903 static bfd_boolean
2904 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
2906 bfd_boolean (*add_symbol_hook)
2907 (bfd *, struct bfd_link_info *, Elf_Internal_Sym *,
2908 const char **, flagword *, asection **, bfd_vma *);
2909 bfd_boolean (*check_relocs)
2910 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
2911 bfd_boolean (*check_directives)
2912 (bfd *, struct bfd_link_info *);
2913 bfd_boolean collect;
2914 Elf_Internal_Shdr *hdr;
2915 bfd_size_type symcount;
2916 bfd_size_type extsymcount;
2917 bfd_size_type extsymoff;
2918 struct elf_link_hash_entry **sym_hash;
2919 bfd_boolean dynamic;
2920 Elf_External_Versym *extversym = NULL;
2921 Elf_External_Versym *ever;
2922 struct elf_link_hash_entry *weaks;
2923 struct elf_link_hash_entry **nondeflt_vers = NULL;
2924 bfd_size_type nondeflt_vers_cnt = 0;
2925 Elf_Internal_Sym *isymbuf = NULL;
2926 Elf_Internal_Sym *isym;
2927 Elf_Internal_Sym *isymend;
2928 const struct elf_backend_data *bed;
2929 bfd_boolean add_needed;
2930 struct elf_link_hash_table * hash_table;
2931 bfd_size_type amt;
2933 hash_table = elf_hash_table (info);
2935 bed = get_elf_backend_data (abfd);
2936 add_symbol_hook = bed->elf_add_symbol_hook;
2937 collect = bed->collect;
2939 if ((abfd->flags & DYNAMIC) == 0)
2940 dynamic = FALSE;
2941 else
2943 dynamic = TRUE;
2945 /* You can't use -r against a dynamic object. Also, there's no
2946 hope of using a dynamic object which does not exactly match
2947 the format of the output file. */
2948 if (info->relocatable
2949 || !is_elf_hash_table (hash_table)
2950 || hash_table->root.creator != abfd->xvec)
2952 bfd_set_error (bfd_error_invalid_operation);
2953 goto error_return;
2957 /* As a GNU extension, any input sections which are named
2958 .gnu.warning.SYMBOL are treated as warning symbols for the given
2959 symbol. This differs from .gnu.warning sections, which generate
2960 warnings when they are included in an output file. */
2961 if (info->executable)
2963 asection *s;
2965 for (s = abfd->sections; s != NULL; s = s->next)
2967 const char *name;
2969 name = bfd_get_section_name (abfd, s);
2970 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
2972 char *msg;
2973 bfd_size_type sz;
2974 bfd_size_type prefix_len;
2975 const char * gnu_warning_prefix = _("warning: ");
2977 name += sizeof ".gnu.warning." - 1;
2979 /* If this is a shared object, then look up the symbol
2980 in the hash table. If it is there, and it is already
2981 been defined, then we will not be using the entry
2982 from this shared object, so we don't need to warn.
2983 FIXME: If we see the definition in a regular object
2984 later on, we will warn, but we shouldn't. The only
2985 fix is to keep track of what warnings we are supposed
2986 to emit, and then handle them all at the end of the
2987 link. */
2988 if (dynamic)
2990 struct elf_link_hash_entry *h;
2992 h = elf_link_hash_lookup (hash_table, name,
2993 FALSE, FALSE, TRUE);
2995 /* FIXME: What about bfd_link_hash_common? */
2996 if (h != NULL
2997 && (h->root.type == bfd_link_hash_defined
2998 || h->root.type == bfd_link_hash_defweak))
3000 /* We don't want to issue this warning. Clobber
3001 the section size so that the warning does not
3002 get copied into the output file. */
3003 s->size = 0;
3004 continue;
3008 sz = s->size;
3009 prefix_len = strlen (gnu_warning_prefix);
3010 msg = bfd_alloc (abfd, prefix_len + sz + 1);
3011 if (msg == NULL)
3012 goto error_return;
3014 strcpy (msg, gnu_warning_prefix);
3015 if (! bfd_get_section_contents (abfd, s, msg + prefix_len, 0, sz))
3016 goto error_return;
3018 msg[prefix_len + sz] = '\0';
3020 if (! (_bfd_generic_link_add_one_symbol
3021 (info, abfd, name, BSF_WARNING, s, 0, msg,
3022 FALSE, collect, NULL)))
3023 goto error_return;
3025 if (! info->relocatable)
3027 /* Clobber the section size so that the warning does
3028 not get copied into the output file. */
3029 s->size = 0;
3035 add_needed = TRUE;
3036 if (! dynamic)
3038 /* If we are creating a shared library, create all the dynamic
3039 sections immediately. We need to attach them to something,
3040 so we attach them to this BFD, provided it is the right
3041 format. FIXME: If there are no input BFD's of the same
3042 format as the output, we can't make a shared library. */
3043 if (info->shared
3044 && is_elf_hash_table (hash_table)
3045 && hash_table->root.creator == abfd->xvec
3046 && ! hash_table->dynamic_sections_created)
3048 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3049 goto error_return;
3052 else if (!is_elf_hash_table (hash_table))
3053 goto error_return;
3054 else
3056 asection *s;
3057 const char *soname = NULL;
3058 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3059 int ret;
3061 /* ld --just-symbols and dynamic objects don't mix very well.
3062 Test for --just-symbols by looking at info set up by
3063 _bfd_elf_link_just_syms. */
3064 if ((s = abfd->sections) != NULL
3065 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3066 goto error_return;
3068 /* If this dynamic lib was specified on the command line with
3069 --as-needed in effect, then we don't want to add a DT_NEEDED
3070 tag unless the lib is actually used. Similary for libs brought
3071 in by another lib's DT_NEEDED. When --no-add-needed is used
3072 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3073 any dynamic library in DT_NEEDED tags in the dynamic lib at
3074 all. */
3075 add_needed = (elf_dyn_lib_class (abfd)
3076 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3077 | DYN_NO_NEEDED)) == 0;
3079 s = bfd_get_section_by_name (abfd, ".dynamic");
3080 if (s != NULL)
3082 bfd_byte *dynbuf;
3083 bfd_byte *extdyn;
3084 int elfsec;
3085 unsigned long shlink;
3087 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3088 goto error_free_dyn;
3090 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3091 if (elfsec == -1)
3092 goto error_free_dyn;
3093 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3095 for (extdyn = dynbuf;
3096 extdyn < dynbuf + s->size;
3097 extdyn += bed->s->sizeof_dyn)
3099 Elf_Internal_Dyn dyn;
3101 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3102 if (dyn.d_tag == DT_SONAME)
3104 unsigned int tagv = dyn.d_un.d_val;
3105 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3106 if (soname == NULL)
3107 goto error_free_dyn;
3109 if (dyn.d_tag == DT_NEEDED)
3111 struct bfd_link_needed_list *n, **pn;
3112 char *fnm, *anm;
3113 unsigned int tagv = dyn.d_un.d_val;
3115 amt = sizeof (struct bfd_link_needed_list);
3116 n = bfd_alloc (abfd, amt);
3117 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3118 if (n == NULL || fnm == NULL)
3119 goto error_free_dyn;
3120 amt = strlen (fnm) + 1;
3121 anm = bfd_alloc (abfd, amt);
3122 if (anm == NULL)
3123 goto error_free_dyn;
3124 memcpy (anm, fnm, amt);
3125 n->name = anm;
3126 n->by = abfd;
3127 n->next = NULL;
3128 for (pn = & hash_table->needed;
3129 *pn != NULL;
3130 pn = &(*pn)->next)
3132 *pn = n;
3134 if (dyn.d_tag == DT_RUNPATH)
3136 struct bfd_link_needed_list *n, **pn;
3137 char *fnm, *anm;
3138 unsigned int tagv = dyn.d_un.d_val;
3140 amt = sizeof (struct bfd_link_needed_list);
3141 n = bfd_alloc (abfd, amt);
3142 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3143 if (n == NULL || fnm == NULL)
3144 goto error_free_dyn;
3145 amt = strlen (fnm) + 1;
3146 anm = bfd_alloc (abfd, amt);
3147 if (anm == NULL)
3148 goto error_free_dyn;
3149 memcpy (anm, fnm, amt);
3150 n->name = anm;
3151 n->by = abfd;
3152 n->next = NULL;
3153 for (pn = & runpath;
3154 *pn != NULL;
3155 pn = &(*pn)->next)
3157 *pn = n;
3159 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3160 if (!runpath && dyn.d_tag == DT_RPATH)
3162 struct bfd_link_needed_list *n, **pn;
3163 char *fnm, *anm;
3164 unsigned int tagv = dyn.d_un.d_val;
3166 amt = sizeof (struct bfd_link_needed_list);
3167 n = bfd_alloc (abfd, amt);
3168 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3169 if (n == NULL || fnm == NULL)
3170 goto error_free_dyn;
3171 amt = strlen (fnm) + 1;
3172 anm = bfd_alloc (abfd, amt);
3173 if (anm == NULL)
3175 error_free_dyn:
3176 free (dynbuf);
3177 goto error_return;
3179 memcpy (anm, fnm, amt);
3180 n->name = anm;
3181 n->by = abfd;
3182 n->next = NULL;
3183 for (pn = & rpath;
3184 *pn != NULL;
3185 pn = &(*pn)->next)
3187 *pn = n;
3191 free (dynbuf);
3194 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3195 frees all more recently bfd_alloc'd blocks as well. */
3196 if (runpath)
3197 rpath = runpath;
3199 if (rpath)
3201 struct bfd_link_needed_list **pn;
3202 for (pn = & hash_table->runpath;
3203 *pn != NULL;
3204 pn = &(*pn)->next)
3206 *pn = rpath;
3209 /* We do not want to include any of the sections in a dynamic
3210 object in the output file. We hack by simply clobbering the
3211 list of sections in the BFD. This could be handled more
3212 cleanly by, say, a new section flag; the existing
3213 SEC_NEVER_LOAD flag is not the one we want, because that one
3214 still implies that the section takes up space in the output
3215 file. */
3216 bfd_section_list_clear (abfd);
3218 /* If this is the first dynamic object found in the link, create
3219 the special sections required for dynamic linking. */
3220 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3221 goto error_return;
3223 /* Find the name to use in a DT_NEEDED entry that refers to this
3224 object. If the object has a DT_SONAME entry, we use it.
3225 Otherwise, if the generic linker stuck something in
3226 elf_dt_name, we use that. Otherwise, we just use the file
3227 name. */
3228 if (soname == NULL || *soname == '\0')
3230 soname = elf_dt_name (abfd);
3231 if (soname == NULL || *soname == '\0')
3232 soname = bfd_get_filename (abfd);
3235 /* Save the SONAME because sometimes the linker emulation code
3236 will need to know it. */
3237 elf_dt_name (abfd) = soname;
3239 ret = elf_add_dt_needed_tag (info, soname, add_needed);
3240 if (ret < 0)
3241 goto error_return;
3243 /* If we have already included this dynamic object in the
3244 link, just ignore it. There is no reason to include a
3245 particular dynamic object more than once. */
3246 if (ret > 0)
3247 return TRUE;
3250 /* If this is a dynamic object, we always link against the .dynsym
3251 symbol table, not the .symtab symbol table. The dynamic linker
3252 will only see the .dynsym symbol table, so there is no reason to
3253 look at .symtab for a dynamic object. */
3255 if (! dynamic || elf_dynsymtab (abfd) == 0)
3256 hdr = &elf_tdata (abfd)->symtab_hdr;
3257 else
3258 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3260 symcount = hdr->sh_size / bed->s->sizeof_sym;
3262 /* The sh_info field of the symtab header tells us where the
3263 external symbols start. We don't care about the local symbols at
3264 this point. */
3265 if (elf_bad_symtab (abfd))
3267 extsymcount = symcount;
3268 extsymoff = 0;
3270 else
3272 extsymcount = symcount - hdr->sh_info;
3273 extsymoff = hdr->sh_info;
3276 sym_hash = NULL;
3277 if (extsymcount != 0)
3279 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3280 NULL, NULL, NULL);
3281 if (isymbuf == NULL)
3282 goto error_return;
3284 /* We store a pointer to the hash table entry for each external
3285 symbol. */
3286 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3287 sym_hash = bfd_alloc (abfd, amt);
3288 if (sym_hash == NULL)
3289 goto error_free_sym;
3290 elf_sym_hashes (abfd) = sym_hash;
3293 if (dynamic)
3295 /* Read in any version definitions. */
3296 if (! _bfd_elf_slurp_version_tables (abfd))
3297 goto error_free_sym;
3299 /* Read in the symbol versions, but don't bother to convert them
3300 to internal format. */
3301 if (elf_dynversym (abfd) != 0)
3303 Elf_Internal_Shdr *versymhdr;
3305 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3306 extversym = bfd_malloc (versymhdr->sh_size);
3307 if (extversym == NULL)
3308 goto error_free_sym;
3309 amt = versymhdr->sh_size;
3310 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3311 || bfd_bread (extversym, amt, abfd) != amt)
3312 goto error_free_vers;
3316 weaks = NULL;
3318 ever = extversym != NULL ? extversym + extsymoff : NULL;
3319 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3320 isym < isymend;
3321 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3323 int bind;
3324 bfd_vma value;
3325 asection *sec;
3326 flagword flags;
3327 const char *name;
3328 struct elf_link_hash_entry *h;
3329 bfd_boolean definition;
3330 bfd_boolean size_change_ok;
3331 bfd_boolean type_change_ok;
3332 bfd_boolean new_weakdef;
3333 bfd_boolean override;
3334 unsigned int old_alignment;
3335 bfd *old_bfd;
3337 override = FALSE;
3339 flags = BSF_NO_FLAGS;
3340 sec = NULL;
3341 value = isym->st_value;
3342 *sym_hash = NULL;
3344 bind = ELF_ST_BIND (isym->st_info);
3345 if (bind == STB_LOCAL)
3347 /* This should be impossible, since ELF requires that all
3348 global symbols follow all local symbols, and that sh_info
3349 point to the first global symbol. Unfortunately, Irix 5
3350 screws this up. */
3351 continue;
3353 else if (bind == STB_GLOBAL)
3355 if (isym->st_shndx != SHN_UNDEF
3356 && isym->st_shndx != SHN_COMMON)
3357 flags = BSF_GLOBAL;
3359 else if (bind == STB_WEAK)
3360 flags = BSF_WEAK;
3361 else
3363 /* Leave it up to the processor backend. */
3366 if (isym->st_shndx == SHN_UNDEF)
3367 sec = bfd_und_section_ptr;
3368 else if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
3370 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3371 if (sec == NULL)
3372 sec = bfd_abs_section_ptr;
3373 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3374 value -= sec->vma;
3376 else if (isym->st_shndx == SHN_ABS)
3377 sec = bfd_abs_section_ptr;
3378 else if (isym->st_shndx == SHN_COMMON)
3380 sec = bfd_com_section_ptr;
3381 /* What ELF calls the size we call the value. What ELF
3382 calls the value we call the alignment. */
3383 value = isym->st_size;
3385 else
3387 /* Leave it up to the processor backend. */
3390 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3391 isym->st_name);
3392 if (name == NULL)
3393 goto error_free_vers;
3395 if (isym->st_shndx == SHN_COMMON
3396 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3398 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3400 if (tcomm == NULL)
3402 tcomm = bfd_make_section (abfd, ".tcommon");
3403 if (tcomm == NULL
3404 || !bfd_set_section_flags (abfd, tcomm, (SEC_ALLOC
3405 | SEC_IS_COMMON
3406 | SEC_LINKER_CREATED
3407 | SEC_THREAD_LOCAL)))
3408 goto error_free_vers;
3410 sec = tcomm;
3412 else if (add_symbol_hook)
3414 if (! (*add_symbol_hook) (abfd, info, isym, &name, &flags, &sec,
3415 &value))
3416 goto error_free_vers;
3418 /* The hook function sets the name to NULL if this symbol
3419 should be skipped for some reason. */
3420 if (name == NULL)
3421 continue;
3424 /* Sanity check that all possibilities were handled. */
3425 if (sec == NULL)
3427 bfd_set_error (bfd_error_bad_value);
3428 goto error_free_vers;
3431 if (bfd_is_und_section (sec)
3432 || bfd_is_com_section (sec))
3433 definition = FALSE;
3434 else
3435 definition = TRUE;
3437 size_change_ok = FALSE;
3438 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
3439 old_alignment = 0;
3440 old_bfd = NULL;
3442 if (is_elf_hash_table (hash_table))
3444 Elf_Internal_Versym iver;
3445 unsigned int vernum = 0;
3446 bfd_boolean skip;
3448 if (ever != NULL)
3450 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3451 vernum = iver.vs_vers & VERSYM_VERSION;
3453 /* If this is a hidden symbol, or if it is not version
3454 1, we append the version name to the symbol name.
3455 However, we do not modify a non-hidden absolute
3456 symbol, because it might be the version symbol
3457 itself. FIXME: What if it isn't? */
3458 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3459 || (vernum > 1 && ! bfd_is_abs_section (sec)))
3461 const char *verstr;
3462 size_t namelen, verlen, newlen;
3463 char *newname, *p;
3465 if (isym->st_shndx != SHN_UNDEF)
3467 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
3469 (*_bfd_error_handler)
3470 (_("%s: %s: invalid version %u (max %d)"),
3471 bfd_archive_filename (abfd), name, vernum,
3472 elf_tdata (abfd)->dynverdef_hdr.sh_info);
3473 bfd_set_error (bfd_error_bad_value);
3474 goto error_free_vers;
3476 else if (vernum > 1)
3477 verstr =
3478 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3479 else
3480 verstr = "";
3482 else
3484 /* We cannot simply test for the number of
3485 entries in the VERNEED section since the
3486 numbers for the needed versions do not start
3487 at 0. */
3488 Elf_Internal_Verneed *t;
3490 verstr = NULL;
3491 for (t = elf_tdata (abfd)->verref;
3492 t != NULL;
3493 t = t->vn_nextref)
3495 Elf_Internal_Vernaux *a;
3497 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3499 if (a->vna_other == vernum)
3501 verstr = a->vna_nodename;
3502 break;
3505 if (a != NULL)
3506 break;
3508 if (verstr == NULL)
3510 (*_bfd_error_handler)
3511 (_("%s: %s: invalid needed version %d"),
3512 bfd_archive_filename (abfd), name, vernum);
3513 bfd_set_error (bfd_error_bad_value);
3514 goto error_free_vers;
3518 namelen = strlen (name);
3519 verlen = strlen (verstr);
3520 newlen = namelen + verlen + 2;
3521 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3522 && isym->st_shndx != SHN_UNDEF)
3523 ++newlen;
3525 newname = bfd_alloc (abfd, newlen);
3526 if (newname == NULL)
3527 goto error_free_vers;
3528 memcpy (newname, name, namelen);
3529 p = newname + namelen;
3530 *p++ = ELF_VER_CHR;
3531 /* If this is a defined non-hidden version symbol,
3532 we add another @ to the name. This indicates the
3533 default version of the symbol. */
3534 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3535 && isym->st_shndx != SHN_UNDEF)
3536 *p++ = ELF_VER_CHR;
3537 memcpy (p, verstr, verlen + 1);
3539 name = newname;
3543 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec, &value,
3544 sym_hash, &skip, &override,
3545 &type_change_ok, &size_change_ok))
3546 goto error_free_vers;
3548 if (skip)
3549 continue;
3551 if (override)
3552 definition = FALSE;
3554 h = *sym_hash;
3555 while (h->root.type == bfd_link_hash_indirect
3556 || h->root.type == bfd_link_hash_warning)
3557 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3559 /* Remember the old alignment if this is a common symbol, so
3560 that we don't reduce the alignment later on. We can't
3561 check later, because _bfd_generic_link_add_one_symbol
3562 will set a default for the alignment which we want to
3563 override. We also remember the old bfd where the existing
3564 definition comes from. */
3565 switch (h->root.type)
3567 default:
3568 break;
3570 case bfd_link_hash_defined:
3571 case bfd_link_hash_defweak:
3572 old_bfd = h->root.u.def.section->owner;
3573 break;
3575 case bfd_link_hash_common:
3576 old_bfd = h->root.u.c.p->section->owner;
3577 old_alignment = h->root.u.c.p->alignment_power;
3578 break;
3581 if (elf_tdata (abfd)->verdef != NULL
3582 && ! override
3583 && vernum > 1
3584 && definition)
3585 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3588 if (! (_bfd_generic_link_add_one_symbol
3589 (info, abfd, name, flags, sec, value, NULL, FALSE, collect,
3590 (struct bfd_link_hash_entry **) sym_hash)))
3591 goto error_free_vers;
3593 h = *sym_hash;
3594 while (h->root.type == bfd_link_hash_indirect
3595 || h->root.type == bfd_link_hash_warning)
3596 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3597 *sym_hash = h;
3599 new_weakdef = FALSE;
3600 if (dynamic
3601 && definition
3602 && (flags & BSF_WEAK) != 0
3603 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3604 && is_elf_hash_table (hash_table)
3605 && h->weakdef == NULL)
3607 /* Keep a list of all weak defined non function symbols from
3608 a dynamic object, using the weakdef field. Later in this
3609 function we will set the weakdef field to the correct
3610 value. We only put non-function symbols from dynamic
3611 objects on this list, because that happens to be the only
3612 time we need to know the normal symbol corresponding to a
3613 weak symbol, and the information is time consuming to
3614 figure out. If the weakdef field is not already NULL,
3615 then this symbol was already defined by some previous
3616 dynamic object, and we will be using that previous
3617 definition anyhow. */
3619 h->weakdef = weaks;
3620 weaks = h;
3621 new_weakdef = TRUE;
3624 /* Set the alignment of a common symbol. */
3625 if (isym->st_shndx == SHN_COMMON
3626 && h->root.type == bfd_link_hash_common)
3628 unsigned int align;
3630 align = bfd_log2 (isym->st_value);
3631 if (align > old_alignment
3632 /* Permit an alignment power of zero if an alignment of one
3633 is specified and no other alignments have been specified. */
3634 || (isym->st_value == 1 && old_alignment == 0))
3635 h->root.u.c.p->alignment_power = align;
3636 else
3637 h->root.u.c.p->alignment_power = old_alignment;
3640 if (is_elf_hash_table (hash_table))
3642 int old_flags;
3643 bfd_boolean dynsym;
3644 int new_flag;
3646 /* Check the alignment when a common symbol is involved. This
3647 can change when a common symbol is overridden by a normal
3648 definition or a common symbol is ignored due to the old
3649 normal definition. We need to make sure the maximum
3650 alignment is maintained. */
3651 if ((old_alignment || isym->st_shndx == SHN_COMMON)
3652 && h->root.type != bfd_link_hash_common)
3654 unsigned int common_align;
3655 unsigned int normal_align;
3656 unsigned int symbol_align;
3657 bfd *normal_bfd;
3658 bfd *common_bfd;
3660 symbol_align = ffs (h->root.u.def.value) - 1;
3661 if (h->root.u.def.section->owner != NULL
3662 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3664 normal_align = h->root.u.def.section->alignment_power;
3665 if (normal_align > symbol_align)
3666 normal_align = symbol_align;
3668 else
3669 normal_align = symbol_align;
3671 if (old_alignment)
3673 common_align = old_alignment;
3674 common_bfd = old_bfd;
3675 normal_bfd = abfd;
3677 else
3679 common_align = bfd_log2 (isym->st_value);
3680 common_bfd = abfd;
3681 normal_bfd = old_bfd;
3684 if (normal_align < common_align)
3685 (*_bfd_error_handler)
3686 (_("Warning: alignment %u of symbol `%s' in %s is smaller than %u in %s"),
3687 1 << normal_align,
3688 name,
3689 bfd_archive_filename (normal_bfd),
3690 1 << common_align,
3691 bfd_archive_filename (common_bfd));
3694 /* Remember the symbol size and type. */
3695 if (isym->st_size != 0
3696 && (definition || h->size == 0))
3698 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3699 (*_bfd_error_handler)
3700 (_("Warning: size of symbol `%s' changed from %lu in %s to %lu in %s"),
3701 name, (unsigned long) h->size,
3702 bfd_archive_filename (old_bfd),
3703 (unsigned long) isym->st_size,
3704 bfd_archive_filename (abfd));
3706 h->size = isym->st_size;
3709 /* If this is a common symbol, then we always want H->SIZE
3710 to be the size of the common symbol. The code just above
3711 won't fix the size if a common symbol becomes larger. We
3712 don't warn about a size change here, because that is
3713 covered by --warn-common. */
3714 if (h->root.type == bfd_link_hash_common)
3715 h->size = h->root.u.c.size;
3717 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3718 && (definition || h->type == STT_NOTYPE))
3720 if (h->type != STT_NOTYPE
3721 && h->type != ELF_ST_TYPE (isym->st_info)
3722 && ! type_change_ok)
3723 (*_bfd_error_handler)
3724 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
3725 name, h->type, ELF_ST_TYPE (isym->st_info),
3726 bfd_archive_filename (abfd));
3728 h->type = ELF_ST_TYPE (isym->st_info);
3731 /* If st_other has a processor-specific meaning, specific
3732 code might be needed here. We never merge the visibility
3733 attribute with the one from a dynamic object. */
3734 if (bed->elf_backend_merge_symbol_attribute)
3735 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3736 dynamic);
3738 if (isym->st_other != 0 && !dynamic)
3740 unsigned char hvis, symvis, other, nvis;
3742 /* Take the balance of OTHER from the definition. */
3743 other = (definition ? isym->st_other : h->other);
3744 other &= ~ ELF_ST_VISIBILITY (-1);
3746 /* Combine visibilities, using the most constraining one. */
3747 hvis = ELF_ST_VISIBILITY (h->other);
3748 symvis = ELF_ST_VISIBILITY (isym->st_other);
3749 if (! hvis)
3750 nvis = symvis;
3751 else if (! symvis)
3752 nvis = hvis;
3753 else
3754 nvis = hvis < symvis ? hvis : symvis;
3756 h->other = other | nvis;
3759 /* Set a flag in the hash table entry indicating the type of
3760 reference or definition we just found. Keep a count of
3761 the number of dynamic symbols we find. A dynamic symbol
3762 is one which is referenced or defined by both a regular
3763 object and a shared object. */
3764 old_flags = h->elf_link_hash_flags;
3765 dynsym = FALSE;
3766 if (! dynamic)
3768 if (! definition)
3770 new_flag = ELF_LINK_HASH_REF_REGULAR;
3771 if (bind != STB_WEAK)
3772 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
3774 else
3775 new_flag = ELF_LINK_HASH_DEF_REGULAR;
3776 if (! info->executable
3777 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
3778 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
3779 dynsym = TRUE;
3781 else
3783 if (! definition)
3784 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
3785 else
3786 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
3787 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
3788 | ELF_LINK_HASH_REF_REGULAR)) != 0
3789 || (h->weakdef != NULL
3790 && ! new_weakdef
3791 && h->weakdef->dynindx != -1))
3792 dynsym = TRUE;
3795 h->elf_link_hash_flags |= new_flag;
3797 /* Check to see if we need to add an indirect symbol for
3798 the default name. */
3799 if (definition || h->root.type == bfd_link_hash_common)
3800 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
3801 &sec, &value, &dynsym,
3802 override))
3803 goto error_free_vers;
3805 if (definition && !dynamic)
3807 char *p = strchr (name, ELF_VER_CHR);
3808 if (p != NULL && p[1] != ELF_VER_CHR)
3810 /* Queue non-default versions so that .symver x, x@FOO
3811 aliases can be checked. */
3812 if (! nondeflt_vers)
3814 amt = (isymend - isym + 1)
3815 * sizeof (struct elf_link_hash_entry *);
3816 nondeflt_vers = bfd_malloc (amt);
3818 nondeflt_vers [nondeflt_vers_cnt++] = h;
3822 if (dynsym && h->dynindx == -1)
3824 if (! bfd_elf_link_record_dynamic_symbol (info, h))
3825 goto error_free_vers;
3826 if (h->weakdef != NULL
3827 && ! new_weakdef
3828 && h->weakdef->dynindx == -1)
3830 if (! bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
3831 goto error_free_vers;
3834 else if (dynsym && h->dynindx != -1)
3835 /* If the symbol already has a dynamic index, but
3836 visibility says it should not be visible, turn it into
3837 a local symbol. */
3838 switch (ELF_ST_VISIBILITY (h->other))
3840 case STV_INTERNAL:
3841 case STV_HIDDEN:
3842 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
3843 dynsym = FALSE;
3844 break;
3847 if (!add_needed
3848 && definition
3849 && dynsym
3850 && (h->elf_link_hash_flags
3851 & ELF_LINK_HASH_REF_REGULAR) != 0)
3853 int ret;
3854 const char *soname = elf_dt_name (abfd);
3856 /* A symbol from a library loaded via DT_NEEDED of some
3857 other library is referenced by a regular object.
3858 Add a DT_NEEDED entry for it. Issue an error if
3859 --no-add-needed is used. */
3860 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
3862 (*_bfd_error_handler)
3863 (_("%s: invalid DSO for symbol `%s' definition"),
3864 bfd_archive_filename (abfd), name);
3865 bfd_set_error (bfd_error_bad_value);
3866 goto error_free_vers;
3869 add_needed = TRUE;
3870 ret = elf_add_dt_needed_tag (info, soname, add_needed);
3871 if (ret < 0)
3872 goto error_free_vers;
3874 BFD_ASSERT (ret == 0);
3879 /* Now that all the symbols from this input file are created, handle
3880 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
3881 if (nondeflt_vers != NULL)
3883 bfd_size_type cnt, symidx;
3885 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
3887 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
3888 char *shortname, *p;
3890 p = strchr (h->root.root.string, ELF_VER_CHR);
3891 if (p == NULL
3892 || (h->root.type != bfd_link_hash_defined
3893 && h->root.type != bfd_link_hash_defweak))
3894 continue;
3896 amt = p - h->root.root.string;
3897 shortname = bfd_malloc (amt + 1);
3898 memcpy (shortname, h->root.root.string, amt);
3899 shortname[amt] = '\0';
3901 hi = (struct elf_link_hash_entry *)
3902 bfd_link_hash_lookup (&hash_table->root, shortname,
3903 FALSE, FALSE, FALSE);
3904 if (hi != NULL
3905 && hi->root.type == h->root.type
3906 && hi->root.u.def.value == h->root.u.def.value
3907 && hi->root.u.def.section == h->root.u.def.section)
3909 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
3910 hi->root.type = bfd_link_hash_indirect;
3911 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
3912 (*bed->elf_backend_copy_indirect_symbol) (bed, h, hi);
3913 sym_hash = elf_sym_hashes (abfd);
3914 if (sym_hash)
3915 for (symidx = 0; symidx < extsymcount; ++symidx)
3916 if (sym_hash[symidx] == hi)
3918 sym_hash[symidx] = h;
3919 break;
3922 free (shortname);
3924 free (nondeflt_vers);
3925 nondeflt_vers = NULL;
3928 if (extversym != NULL)
3930 free (extversym);
3931 extversym = NULL;
3934 if (isymbuf != NULL)
3935 free (isymbuf);
3936 isymbuf = NULL;
3938 /* Now set the weakdefs field correctly for all the weak defined
3939 symbols we found. The only way to do this is to search all the
3940 symbols. Since we only need the information for non functions in
3941 dynamic objects, that's the only time we actually put anything on
3942 the list WEAKS. We need this information so that if a regular
3943 object refers to a symbol defined weakly in a dynamic object, the
3944 real symbol in the dynamic object is also put in the dynamic
3945 symbols; we also must arrange for both symbols to point to the
3946 same memory location. We could handle the general case of symbol
3947 aliasing, but a general symbol alias can only be generated in
3948 assembler code, handling it correctly would be very time
3949 consuming, and other ELF linkers don't handle general aliasing
3950 either. */
3951 if (weaks != NULL)
3953 struct elf_link_hash_entry **hpp;
3954 struct elf_link_hash_entry **hppend;
3955 struct elf_link_hash_entry **sorted_sym_hash;
3956 struct elf_link_hash_entry *h;
3957 size_t sym_count;
3959 /* Since we have to search the whole symbol list for each weak
3960 defined symbol, search time for N weak defined symbols will be
3961 O(N^2). Binary search will cut it down to O(NlogN). */
3962 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3963 sorted_sym_hash = bfd_malloc (amt);
3964 if (sorted_sym_hash == NULL)
3965 goto error_return;
3966 sym_hash = sorted_sym_hash;
3967 hpp = elf_sym_hashes (abfd);
3968 hppend = hpp + extsymcount;
3969 sym_count = 0;
3970 for (; hpp < hppend; hpp++)
3972 h = *hpp;
3973 if (h != NULL
3974 && h->root.type == bfd_link_hash_defined
3975 && h->type != STT_FUNC)
3977 *sym_hash = h;
3978 sym_hash++;
3979 sym_count++;
3983 qsort (sorted_sym_hash, sym_count,
3984 sizeof (struct elf_link_hash_entry *),
3985 elf_sort_symbol);
3987 while (weaks != NULL)
3989 struct elf_link_hash_entry *hlook;
3990 asection *slook;
3991 bfd_vma vlook;
3992 long ilook;
3993 size_t i, j, idx;
3995 hlook = weaks;
3996 weaks = hlook->weakdef;
3997 hlook->weakdef = NULL;
3999 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4000 || hlook->root.type == bfd_link_hash_defweak
4001 || hlook->root.type == bfd_link_hash_common
4002 || hlook->root.type == bfd_link_hash_indirect);
4003 slook = hlook->root.u.def.section;
4004 vlook = hlook->root.u.def.value;
4006 ilook = -1;
4007 i = 0;
4008 j = sym_count;
4009 while (i < j)
4011 bfd_signed_vma vdiff;
4012 idx = (i + j) / 2;
4013 h = sorted_sym_hash [idx];
4014 vdiff = vlook - h->root.u.def.value;
4015 if (vdiff < 0)
4016 j = idx;
4017 else if (vdiff > 0)
4018 i = idx + 1;
4019 else
4021 long sdiff = slook->id - h->root.u.def.section->id;
4022 if (sdiff < 0)
4023 j = idx;
4024 else if (sdiff > 0)
4025 i = idx + 1;
4026 else
4028 ilook = idx;
4029 break;
4034 /* We didn't find a value/section match. */
4035 if (ilook == -1)
4036 continue;
4038 for (i = ilook; i < sym_count; i++)
4040 h = sorted_sym_hash [i];
4042 /* Stop if value or section doesn't match. */
4043 if (h->root.u.def.value != vlook
4044 || h->root.u.def.section != slook)
4045 break;
4046 else if (h != hlook)
4048 hlook->weakdef = h;
4050 /* If the weak definition is in the list of dynamic
4051 symbols, make sure the real definition is put
4052 there as well. */
4053 if (hlook->dynindx != -1 && h->dynindx == -1)
4055 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4056 goto error_return;
4059 /* If the real definition is in the list of dynamic
4060 symbols, make sure the weak definition is put
4061 there as well. If we don't do this, then the
4062 dynamic loader might not merge the entries for the
4063 real definition and the weak definition. */
4064 if (h->dynindx != -1 && hlook->dynindx == -1)
4066 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4067 goto error_return;
4069 break;
4074 free (sorted_sym_hash);
4077 check_directives = get_elf_backend_data (abfd)->check_directives;
4078 if (check_directives)
4079 check_directives (abfd, info);
4081 /* If this object is the same format as the output object, and it is
4082 not a shared library, then let the backend look through the
4083 relocs.
4085 This is required to build global offset table entries and to
4086 arrange for dynamic relocs. It is not required for the
4087 particular common case of linking non PIC code, even when linking
4088 against shared libraries, but unfortunately there is no way of
4089 knowing whether an object file has been compiled PIC or not.
4090 Looking through the relocs is not particularly time consuming.
4091 The problem is that we must either (1) keep the relocs in memory,
4092 which causes the linker to require additional runtime memory or
4093 (2) read the relocs twice from the input file, which wastes time.
4094 This would be a good case for using mmap.
4096 I have no idea how to handle linking PIC code into a file of a
4097 different format. It probably can't be done. */
4098 check_relocs = get_elf_backend_data (abfd)->check_relocs;
4099 if (! dynamic
4100 && is_elf_hash_table (hash_table)
4101 && hash_table->root.creator == abfd->xvec
4102 && check_relocs != NULL)
4104 asection *o;
4106 for (o = abfd->sections; o != NULL; o = o->next)
4108 Elf_Internal_Rela *internal_relocs;
4109 bfd_boolean ok;
4111 if ((o->flags & SEC_RELOC) == 0
4112 || o->reloc_count == 0
4113 || ((info->strip == strip_all || info->strip == strip_debugger)
4114 && (o->flags & SEC_DEBUGGING) != 0)
4115 || bfd_is_abs_section (o->output_section))
4116 continue;
4118 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4119 info->keep_memory);
4120 if (internal_relocs == NULL)
4121 goto error_return;
4123 ok = (*check_relocs) (abfd, info, o, internal_relocs);
4125 if (elf_section_data (o)->relocs != internal_relocs)
4126 free (internal_relocs);
4128 if (! ok)
4129 goto error_return;
4133 /* If this is a non-traditional link, try to optimize the handling
4134 of the .stab/.stabstr sections. */
4135 if (! dynamic
4136 && ! info->traditional_format
4137 && is_elf_hash_table (hash_table)
4138 && (info->strip != strip_all && info->strip != strip_debugger))
4140 asection *stabstr;
4142 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4143 if (stabstr != NULL)
4145 bfd_size_type string_offset = 0;
4146 asection *stab;
4148 for (stab = abfd->sections; stab; stab = stab->next)
4149 if (strncmp (".stab", stab->name, 5) == 0
4150 && (!stab->name[5] ||
4151 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4152 && (stab->flags & SEC_MERGE) == 0
4153 && !bfd_is_abs_section (stab->output_section))
4155 struct bfd_elf_section_data *secdata;
4157 secdata = elf_section_data (stab);
4158 if (! _bfd_link_section_stabs (abfd,
4159 &hash_table->stab_info,
4160 stab, stabstr,
4161 &secdata->sec_info,
4162 &string_offset))
4163 goto error_return;
4164 if (secdata->sec_info)
4165 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4170 if (is_elf_hash_table (hash_table))
4172 /* Add this bfd to the loaded list. */
4173 struct elf_link_loaded_list *n;
4175 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4176 if (n == NULL)
4177 goto error_return;
4178 n->abfd = abfd;
4179 n->next = hash_table->loaded;
4180 hash_table->loaded = n;
4183 return TRUE;
4185 error_free_vers:
4186 if (nondeflt_vers != NULL)
4187 free (nondeflt_vers);
4188 if (extversym != NULL)
4189 free (extversym);
4190 error_free_sym:
4191 if (isymbuf != NULL)
4192 free (isymbuf);
4193 error_return:
4194 return FALSE;
4197 /* Add symbols from an ELF archive file to the linker hash table. We
4198 don't use _bfd_generic_link_add_archive_symbols because of a
4199 problem which arises on UnixWare. The UnixWare libc.so is an
4200 archive which includes an entry libc.so.1 which defines a bunch of
4201 symbols. The libc.so archive also includes a number of other
4202 object files, which also define symbols, some of which are the same
4203 as those defined in libc.so.1. Correct linking requires that we
4204 consider each object file in turn, and include it if it defines any
4205 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4206 this; it looks through the list of undefined symbols, and includes
4207 any object file which defines them. When this algorithm is used on
4208 UnixWare, it winds up pulling in libc.so.1 early and defining a
4209 bunch of symbols. This means that some of the other objects in the
4210 archive are not included in the link, which is incorrect since they
4211 precede libc.so.1 in the archive.
4213 Fortunately, ELF archive handling is simpler than that done by
4214 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4215 oddities. In ELF, if we find a symbol in the archive map, and the
4216 symbol is currently undefined, we know that we must pull in that
4217 object file.
4219 Unfortunately, we do have to make multiple passes over the symbol
4220 table until nothing further is resolved. */
4222 static bfd_boolean
4223 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4225 symindex c;
4226 bfd_boolean *defined = NULL;
4227 bfd_boolean *included = NULL;
4228 carsym *symdefs;
4229 bfd_boolean loop;
4230 bfd_size_type amt;
4232 if (! bfd_has_map (abfd))
4234 /* An empty archive is a special case. */
4235 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4236 return TRUE;
4237 bfd_set_error (bfd_error_no_armap);
4238 return FALSE;
4241 /* Keep track of all symbols we know to be already defined, and all
4242 files we know to be already included. This is to speed up the
4243 second and subsequent passes. */
4244 c = bfd_ardata (abfd)->symdef_count;
4245 if (c == 0)
4246 return TRUE;
4247 amt = c;
4248 amt *= sizeof (bfd_boolean);
4249 defined = bfd_zmalloc (amt);
4250 included = bfd_zmalloc (amt);
4251 if (defined == NULL || included == NULL)
4252 goto error_return;
4254 symdefs = bfd_ardata (abfd)->symdefs;
4258 file_ptr last;
4259 symindex i;
4260 carsym *symdef;
4261 carsym *symdefend;
4263 loop = FALSE;
4264 last = -1;
4266 symdef = symdefs;
4267 symdefend = symdef + c;
4268 for (i = 0; symdef < symdefend; symdef++, i++)
4270 struct elf_link_hash_entry *h;
4271 bfd *element;
4272 struct bfd_link_hash_entry *undefs_tail;
4273 symindex mark;
4275 if (defined[i] || included[i])
4276 continue;
4277 if (symdef->file_offset == last)
4279 included[i] = TRUE;
4280 continue;
4283 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
4284 FALSE, FALSE, FALSE);
4286 if (h == NULL)
4288 char *p, *copy;
4289 size_t len, first;
4291 /* If this is a default version (the name contains @@),
4292 look up the symbol again with only one `@' as well
4293 as without the version. The effect is that references
4294 to the symbol with and without the version will be
4295 matched by the default symbol in the archive. */
4297 p = strchr (symdef->name, ELF_VER_CHR);
4298 if (p == NULL || p[1] != ELF_VER_CHR)
4299 continue;
4301 /* First check with only one `@'. */
4302 len = strlen (symdef->name);
4303 copy = bfd_alloc (abfd, len);
4304 if (copy == NULL)
4305 goto error_return;
4306 first = p - symdef->name + 1;
4307 memcpy (copy, symdef->name, first);
4308 memcpy (copy + first, symdef->name + first + 1, len - first);
4310 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4311 FALSE, FALSE, FALSE);
4313 if (h == NULL)
4315 /* We also need to check references to the symbol
4316 without the version. */
4318 copy[first - 1] = '\0';
4319 h = elf_link_hash_lookup (elf_hash_table (info),
4320 copy, FALSE, FALSE, FALSE);
4323 bfd_release (abfd, copy);
4326 if (h == NULL)
4327 continue;
4329 if (h->root.type == bfd_link_hash_common)
4331 /* We currently have a common symbol. The archive map contains
4332 a reference to this symbol, so we may want to include it. We
4333 only want to include it however, if this archive element
4334 contains a definition of the symbol, not just another common
4335 declaration of it.
4337 Unfortunately some archivers (including GNU ar) will put
4338 declarations of common symbols into their archive maps, as
4339 well as real definitions, so we cannot just go by the archive
4340 map alone. Instead we must read in the element's symbol
4341 table and check that to see what kind of symbol definition
4342 this is. */
4343 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4344 continue;
4346 else if (h->root.type != bfd_link_hash_undefined)
4348 if (h->root.type != bfd_link_hash_undefweak)
4349 defined[i] = TRUE;
4350 continue;
4353 /* We need to include this archive member. */
4354 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4355 if (element == NULL)
4356 goto error_return;
4358 if (! bfd_check_format (element, bfd_object))
4359 goto error_return;
4361 /* Doublecheck that we have not included this object
4362 already--it should be impossible, but there may be
4363 something wrong with the archive. */
4364 if (element->archive_pass != 0)
4366 bfd_set_error (bfd_error_bad_value);
4367 goto error_return;
4369 element->archive_pass = 1;
4371 undefs_tail = info->hash->undefs_tail;
4373 if (! (*info->callbacks->add_archive_element) (info, element,
4374 symdef->name))
4375 goto error_return;
4376 if (! bfd_link_add_symbols (element, info))
4377 goto error_return;
4379 /* If there are any new undefined symbols, we need to make
4380 another pass through the archive in order to see whether
4381 they can be defined. FIXME: This isn't perfect, because
4382 common symbols wind up on undefs_tail and because an
4383 undefined symbol which is defined later on in this pass
4384 does not require another pass. This isn't a bug, but it
4385 does make the code less efficient than it could be. */
4386 if (undefs_tail != info->hash->undefs_tail)
4387 loop = TRUE;
4389 /* Look backward to mark all symbols from this object file
4390 which we have already seen in this pass. */
4391 mark = i;
4394 included[mark] = TRUE;
4395 if (mark == 0)
4396 break;
4397 --mark;
4399 while (symdefs[mark].file_offset == symdef->file_offset);
4401 /* We mark subsequent symbols from this object file as we go
4402 on through the loop. */
4403 last = symdef->file_offset;
4406 while (loop);
4408 free (defined);
4409 free (included);
4411 return TRUE;
4413 error_return:
4414 if (defined != NULL)
4415 free (defined);
4416 if (included != NULL)
4417 free (included);
4418 return FALSE;
4421 /* Given an ELF BFD, add symbols to the global hash table as
4422 appropriate. */
4424 bfd_boolean
4425 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4427 switch (bfd_get_format (abfd))
4429 case bfd_object:
4430 return elf_link_add_object_symbols (abfd, info);
4431 case bfd_archive:
4432 return elf_link_add_archive_symbols (abfd, info);
4433 default:
4434 bfd_set_error (bfd_error_wrong_format);
4435 return FALSE;
4439 /* This function will be called though elf_link_hash_traverse to store
4440 all hash value of the exported symbols in an array. */
4442 static bfd_boolean
4443 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4445 unsigned long **valuep = data;
4446 const char *name;
4447 char *p;
4448 unsigned long ha;
4449 char *alc = NULL;
4451 if (h->root.type == bfd_link_hash_warning)
4452 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4454 /* Ignore indirect symbols. These are added by the versioning code. */
4455 if (h->dynindx == -1)
4456 return TRUE;
4458 name = h->root.root.string;
4459 p = strchr (name, ELF_VER_CHR);
4460 if (p != NULL)
4462 alc = bfd_malloc (p - name + 1);
4463 memcpy (alc, name, p - name);
4464 alc[p - name] = '\0';
4465 name = alc;
4468 /* Compute the hash value. */
4469 ha = bfd_elf_hash (name);
4471 /* Store the found hash value in the array given as the argument. */
4472 *(*valuep)++ = ha;
4474 /* And store it in the struct so that we can put it in the hash table
4475 later. */
4476 h->elf_hash_value = ha;
4478 if (alc != NULL)
4479 free (alc);
4481 return TRUE;
4484 /* Array used to determine the number of hash table buckets to use
4485 based on the number of symbols there are. If there are fewer than
4486 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4487 fewer than 37 we use 17 buckets, and so forth. We never use more
4488 than 32771 buckets. */
4490 static const size_t elf_buckets[] =
4492 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4493 16411, 32771, 0
4496 /* Compute bucket count for hashing table. We do not use a static set
4497 of possible tables sizes anymore. Instead we determine for all
4498 possible reasonable sizes of the table the outcome (i.e., the
4499 number of collisions etc) and choose the best solution. The
4500 weighting functions are not too simple to allow the table to grow
4501 without bounds. Instead one of the weighting factors is the size.
4502 Therefore the result is always a good payoff between few collisions
4503 (= short chain lengths) and table size. */
4504 static size_t
4505 compute_bucket_count (struct bfd_link_info *info)
4507 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4508 size_t best_size = 0;
4509 unsigned long int *hashcodes;
4510 unsigned long int *hashcodesp;
4511 unsigned long int i;
4512 bfd_size_type amt;
4514 /* Compute the hash values for all exported symbols. At the same
4515 time store the values in an array so that we could use them for
4516 optimizations. */
4517 amt = dynsymcount;
4518 amt *= sizeof (unsigned long int);
4519 hashcodes = bfd_malloc (amt);
4520 if (hashcodes == NULL)
4521 return 0;
4522 hashcodesp = hashcodes;
4524 /* Put all hash values in HASHCODES. */
4525 elf_link_hash_traverse (elf_hash_table (info),
4526 elf_collect_hash_codes, &hashcodesp);
4528 /* We have a problem here. The following code to optimize the table
4529 size requires an integer type with more the 32 bits. If
4530 BFD_HOST_U_64_BIT is set we know about such a type. */
4531 #ifdef BFD_HOST_U_64_BIT
4532 if (info->optimize)
4534 unsigned long int nsyms = hashcodesp - hashcodes;
4535 size_t minsize;
4536 size_t maxsize;
4537 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4538 unsigned long int *counts ;
4539 bfd *dynobj = elf_hash_table (info)->dynobj;
4540 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4542 /* Possible optimization parameters: if we have NSYMS symbols we say
4543 that the hashing table must at least have NSYMS/4 and at most
4544 2*NSYMS buckets. */
4545 minsize = nsyms / 4;
4546 if (minsize == 0)
4547 minsize = 1;
4548 best_size = maxsize = nsyms * 2;
4550 /* Create array where we count the collisions in. We must use bfd_malloc
4551 since the size could be large. */
4552 amt = maxsize;
4553 amt *= sizeof (unsigned long int);
4554 counts = bfd_malloc (amt);
4555 if (counts == NULL)
4557 free (hashcodes);
4558 return 0;
4561 /* Compute the "optimal" size for the hash table. The criteria is a
4562 minimal chain length. The minor criteria is (of course) the size
4563 of the table. */
4564 for (i = minsize; i < maxsize; ++i)
4566 /* Walk through the array of hashcodes and count the collisions. */
4567 BFD_HOST_U_64_BIT max;
4568 unsigned long int j;
4569 unsigned long int fact;
4571 memset (counts, '\0', i * sizeof (unsigned long int));
4573 /* Determine how often each hash bucket is used. */
4574 for (j = 0; j < nsyms; ++j)
4575 ++counts[hashcodes[j] % i];
4577 /* For the weight function we need some information about the
4578 pagesize on the target. This is information need not be 100%
4579 accurate. Since this information is not available (so far) we
4580 define it here to a reasonable default value. If it is crucial
4581 to have a better value some day simply define this value. */
4582 # ifndef BFD_TARGET_PAGESIZE
4583 # define BFD_TARGET_PAGESIZE (4096)
4584 # endif
4586 /* We in any case need 2 + NSYMS entries for the size values and
4587 the chains. */
4588 max = (2 + nsyms) * (bed->s->arch_size / 8);
4590 # if 1
4591 /* Variant 1: optimize for short chains. We add the squares
4592 of all the chain lengths (which favors many small chain
4593 over a few long chains). */
4594 for (j = 0; j < i; ++j)
4595 max += counts[j] * counts[j];
4597 /* This adds penalties for the overall size of the table. */
4598 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4599 max *= fact * fact;
4600 # else
4601 /* Variant 2: Optimize a lot more for small table. Here we
4602 also add squares of the size but we also add penalties for
4603 empty slots (the +1 term). */
4604 for (j = 0; j < i; ++j)
4605 max += (1 + counts[j]) * (1 + counts[j]);
4607 /* The overall size of the table is considered, but not as
4608 strong as in variant 1, where it is squared. */
4609 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4610 max *= fact;
4611 # endif
4613 /* Compare with current best results. */
4614 if (max < best_chlen)
4616 best_chlen = max;
4617 best_size = i;
4621 free (counts);
4623 else
4624 #endif /* defined (BFD_HOST_U_64_BIT) */
4626 /* This is the fallback solution if no 64bit type is available or if we
4627 are not supposed to spend much time on optimizations. We select the
4628 bucket count using a fixed set of numbers. */
4629 for (i = 0; elf_buckets[i] != 0; i++)
4631 best_size = elf_buckets[i];
4632 if (dynsymcount < elf_buckets[i + 1])
4633 break;
4637 /* Free the arrays we needed. */
4638 free (hashcodes);
4640 return best_size;
4643 /* Set up the sizes and contents of the ELF dynamic sections. This is
4644 called by the ELF linker emulation before_allocation routine. We
4645 must set the sizes of the sections before the linker sets the
4646 addresses of the various sections. */
4648 bfd_boolean
4649 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4650 const char *soname,
4651 const char *rpath,
4652 const char *filter_shlib,
4653 const char * const *auxiliary_filters,
4654 struct bfd_link_info *info,
4655 asection **sinterpptr,
4656 struct bfd_elf_version_tree *verdefs)
4658 bfd_size_type soname_indx;
4659 bfd *dynobj;
4660 const struct elf_backend_data *bed;
4661 struct elf_assign_sym_version_info asvinfo;
4663 *sinterpptr = NULL;
4665 soname_indx = (bfd_size_type) -1;
4667 if (!is_elf_hash_table (info->hash))
4668 return TRUE;
4670 elf_tdata (output_bfd)->relro = info->relro;
4671 if (info->execstack)
4672 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4673 else if (info->noexecstack)
4674 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4675 else
4677 bfd *inputobj;
4678 asection *notesec = NULL;
4679 int exec = 0;
4681 for (inputobj = info->input_bfds;
4682 inputobj;
4683 inputobj = inputobj->link_next)
4685 asection *s;
4687 if (inputobj->flags & DYNAMIC)
4688 continue;
4689 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
4690 if (s)
4692 if (s->flags & SEC_CODE)
4693 exec = PF_X;
4694 notesec = s;
4696 else
4697 exec = PF_X;
4699 if (notesec)
4701 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
4702 if (exec && info->relocatable
4703 && notesec->output_section != bfd_abs_section_ptr)
4704 notesec->output_section->flags |= SEC_CODE;
4708 /* Any syms created from now on start with -1 in
4709 got.refcount/offset and plt.refcount/offset. */
4710 elf_hash_table (info)->init_refcount = elf_hash_table (info)->init_offset;
4712 /* The backend may have to create some sections regardless of whether
4713 we're dynamic or not. */
4714 bed = get_elf_backend_data (output_bfd);
4715 if (bed->elf_backend_always_size_sections
4716 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
4717 return FALSE;
4719 dynobj = elf_hash_table (info)->dynobj;
4721 /* If there were no dynamic objects in the link, there is nothing to
4722 do here. */
4723 if (dynobj == NULL)
4724 return TRUE;
4726 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
4727 return FALSE;
4729 if (elf_hash_table (info)->dynamic_sections_created)
4731 struct elf_info_failed eif;
4732 struct elf_link_hash_entry *h;
4733 asection *dynstr;
4734 struct bfd_elf_version_tree *t;
4735 struct bfd_elf_version_expr *d;
4736 bfd_boolean all_defined;
4738 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
4739 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
4741 if (soname != NULL)
4743 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
4744 soname, TRUE);
4745 if (soname_indx == (bfd_size_type) -1
4746 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
4747 return FALSE;
4750 if (info->symbolic)
4752 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
4753 return FALSE;
4754 info->flags |= DF_SYMBOLIC;
4757 if (rpath != NULL)
4759 bfd_size_type indx;
4761 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
4762 TRUE);
4763 if (indx == (bfd_size_type) -1
4764 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
4765 return FALSE;
4767 if (info->new_dtags)
4769 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
4770 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
4771 return FALSE;
4775 if (filter_shlib != NULL)
4777 bfd_size_type indx;
4779 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
4780 filter_shlib, TRUE);
4781 if (indx == (bfd_size_type) -1
4782 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
4783 return FALSE;
4786 if (auxiliary_filters != NULL)
4788 const char * const *p;
4790 for (p = auxiliary_filters; *p != NULL; p++)
4792 bfd_size_type indx;
4794 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
4795 *p, TRUE);
4796 if (indx == (bfd_size_type) -1
4797 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
4798 return FALSE;
4802 eif.info = info;
4803 eif.verdefs = verdefs;
4804 eif.failed = FALSE;
4806 /* If we are supposed to export all symbols into the dynamic symbol
4807 table (this is not the normal case), then do so. */
4808 if (info->export_dynamic)
4810 elf_link_hash_traverse (elf_hash_table (info),
4811 _bfd_elf_export_symbol,
4812 &eif);
4813 if (eif.failed)
4814 return FALSE;
4817 /* Make all global versions with definition. */
4818 for (t = verdefs; t != NULL; t = t->next)
4819 for (d = t->globals.list; d != NULL; d = d->next)
4820 if (!d->symver && d->symbol)
4822 const char *verstr, *name;
4823 size_t namelen, verlen, newlen;
4824 char *newname, *p;
4825 struct elf_link_hash_entry *newh;
4827 name = d->symbol;
4828 namelen = strlen (name);
4829 verstr = t->name;
4830 verlen = strlen (verstr);
4831 newlen = namelen + verlen + 3;
4833 newname = bfd_malloc (newlen);
4834 if (newname == NULL)
4835 return FALSE;
4836 memcpy (newname, name, namelen);
4838 /* Check the hidden versioned definition. */
4839 p = newname + namelen;
4840 *p++ = ELF_VER_CHR;
4841 memcpy (p, verstr, verlen + 1);
4842 newh = elf_link_hash_lookup (elf_hash_table (info),
4843 newname, FALSE, FALSE,
4844 FALSE);
4845 if (newh == NULL
4846 || (newh->root.type != bfd_link_hash_defined
4847 && newh->root.type != bfd_link_hash_defweak))
4849 /* Check the default versioned definition. */
4850 *p++ = ELF_VER_CHR;
4851 memcpy (p, verstr, verlen + 1);
4852 newh = elf_link_hash_lookup (elf_hash_table (info),
4853 newname, FALSE, FALSE,
4854 FALSE);
4856 free (newname);
4858 /* Mark this version if there is a definition and it is
4859 not defined in a shared object. */
4860 if (newh != NULL
4861 && ((newh->elf_link_hash_flags
4862 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)
4863 && (newh->root.type == bfd_link_hash_defined
4864 || newh->root.type == bfd_link_hash_defweak))
4865 d->symver = 1;
4868 /* Attach all the symbols to their version information. */
4869 asvinfo.output_bfd = output_bfd;
4870 asvinfo.info = info;
4871 asvinfo.verdefs = verdefs;
4872 asvinfo.failed = FALSE;
4874 elf_link_hash_traverse (elf_hash_table (info),
4875 _bfd_elf_link_assign_sym_version,
4876 &asvinfo);
4877 if (asvinfo.failed)
4878 return FALSE;
4880 if (!info->allow_undefined_version)
4882 /* Check if all global versions have a definition. */
4883 all_defined = TRUE;
4884 for (t = verdefs; t != NULL; t = t->next)
4885 for (d = t->globals.list; d != NULL; d = d->next)
4886 if (!d->symver && !d->script)
4888 (*_bfd_error_handler)
4889 (_("%s: undefined version: %s"),
4890 d->pattern, t->name);
4891 all_defined = FALSE;
4894 if (!all_defined)
4896 bfd_set_error (bfd_error_bad_value);
4897 return FALSE;
4901 /* Find all symbols which were defined in a dynamic object and make
4902 the backend pick a reasonable value for them. */
4903 elf_link_hash_traverse (elf_hash_table (info),
4904 _bfd_elf_adjust_dynamic_symbol,
4905 &eif);
4906 if (eif.failed)
4907 return FALSE;
4909 /* Add some entries to the .dynamic section. We fill in some of the
4910 values later, in elf_bfd_final_link, but we must add the entries
4911 now so that we know the final size of the .dynamic section. */
4913 /* If there are initialization and/or finalization functions to
4914 call then add the corresponding DT_INIT/DT_FINI entries. */
4915 h = (info->init_function
4916 ? elf_link_hash_lookup (elf_hash_table (info),
4917 info->init_function, FALSE,
4918 FALSE, FALSE)
4919 : NULL);
4920 if (h != NULL
4921 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
4922 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
4924 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
4925 return FALSE;
4927 h = (info->fini_function
4928 ? elf_link_hash_lookup (elf_hash_table (info),
4929 info->fini_function, FALSE,
4930 FALSE, FALSE)
4931 : NULL);
4932 if (h != NULL
4933 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
4934 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
4936 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
4937 return FALSE;
4940 if (bfd_get_section_by_name (output_bfd, ".preinit_array") != NULL)
4942 /* DT_PREINIT_ARRAY is not allowed in shared library. */
4943 if (! info->executable)
4945 bfd *sub;
4946 asection *o;
4948 for (sub = info->input_bfds; sub != NULL;
4949 sub = sub->link_next)
4950 for (o = sub->sections; o != NULL; o = o->next)
4951 if (elf_section_data (o)->this_hdr.sh_type
4952 == SHT_PREINIT_ARRAY)
4954 (*_bfd_error_handler)
4955 (_("%s: .preinit_array section is not allowed in DSO"),
4956 bfd_archive_filename (sub));
4957 break;
4960 bfd_set_error (bfd_error_nonrepresentable_section);
4961 return FALSE;
4964 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
4965 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
4966 return FALSE;
4968 if (bfd_get_section_by_name (output_bfd, ".init_array") != NULL)
4970 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
4971 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
4972 return FALSE;
4974 if (bfd_get_section_by_name (output_bfd, ".fini_array") != NULL)
4976 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
4977 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
4978 return FALSE;
4981 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
4982 /* If .dynstr is excluded from the link, we don't want any of
4983 these tags. Strictly, we should be checking each section
4984 individually; This quick check covers for the case where
4985 someone does a /DISCARD/ : { *(*) }. */
4986 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
4988 bfd_size_type strsize;
4990 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
4991 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
4992 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
4993 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
4994 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
4995 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
4996 bed->s->sizeof_sym))
4997 return FALSE;
5001 /* The backend must work out the sizes of all the other dynamic
5002 sections. */
5003 if (bed->elf_backend_size_dynamic_sections
5004 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5005 return FALSE;
5007 if (elf_hash_table (info)->dynamic_sections_created)
5009 bfd_size_type dynsymcount;
5010 asection *s;
5011 size_t bucketcount = 0;
5012 size_t hash_entry_size;
5013 unsigned int dtagcount;
5015 /* Set up the version definition section. */
5016 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5017 BFD_ASSERT (s != NULL);
5019 /* We may have created additional version definitions if we are
5020 just linking a regular application. */
5021 verdefs = asvinfo.verdefs;
5023 /* Skip anonymous version tag. */
5024 if (verdefs != NULL && verdefs->vernum == 0)
5025 verdefs = verdefs->next;
5027 if (verdefs == NULL)
5028 _bfd_strip_section_from_output (info, s);
5029 else
5031 unsigned int cdefs;
5032 bfd_size_type size;
5033 struct bfd_elf_version_tree *t;
5034 bfd_byte *p;
5035 Elf_Internal_Verdef def;
5036 Elf_Internal_Verdaux defaux;
5038 cdefs = 0;
5039 size = 0;
5041 /* Make space for the base version. */
5042 size += sizeof (Elf_External_Verdef);
5043 size += sizeof (Elf_External_Verdaux);
5044 ++cdefs;
5046 for (t = verdefs; t != NULL; t = t->next)
5048 struct bfd_elf_version_deps *n;
5050 size += sizeof (Elf_External_Verdef);
5051 size += sizeof (Elf_External_Verdaux);
5052 ++cdefs;
5054 for (n = t->deps; n != NULL; n = n->next)
5055 size += sizeof (Elf_External_Verdaux);
5058 s->size = size;
5059 s->contents = bfd_alloc (output_bfd, s->size);
5060 if (s->contents == NULL && s->size != 0)
5061 return FALSE;
5063 /* Fill in the version definition section. */
5065 p = s->contents;
5067 def.vd_version = VER_DEF_CURRENT;
5068 def.vd_flags = VER_FLG_BASE;
5069 def.vd_ndx = 1;
5070 def.vd_cnt = 1;
5071 def.vd_aux = sizeof (Elf_External_Verdef);
5072 def.vd_next = (sizeof (Elf_External_Verdef)
5073 + sizeof (Elf_External_Verdaux));
5075 if (soname_indx != (bfd_size_type) -1)
5077 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5078 soname_indx);
5079 def.vd_hash = bfd_elf_hash (soname);
5080 defaux.vda_name = soname_indx;
5082 else
5084 const char *name;
5085 bfd_size_type indx;
5087 name = basename (output_bfd->filename);
5088 def.vd_hash = bfd_elf_hash (name);
5089 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5090 name, FALSE);
5091 if (indx == (bfd_size_type) -1)
5092 return FALSE;
5093 defaux.vda_name = indx;
5095 defaux.vda_next = 0;
5097 _bfd_elf_swap_verdef_out (output_bfd, &def,
5098 (Elf_External_Verdef *) p);
5099 p += sizeof (Elf_External_Verdef);
5100 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5101 (Elf_External_Verdaux *) p);
5102 p += sizeof (Elf_External_Verdaux);
5104 for (t = verdefs; t != NULL; t = t->next)
5106 unsigned int cdeps;
5107 struct bfd_elf_version_deps *n;
5108 struct elf_link_hash_entry *h;
5109 struct bfd_link_hash_entry *bh;
5111 cdeps = 0;
5112 for (n = t->deps; n != NULL; n = n->next)
5113 ++cdeps;
5115 /* Add a symbol representing this version. */
5116 bh = NULL;
5117 if (! (_bfd_generic_link_add_one_symbol
5118 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5119 0, NULL, FALSE,
5120 get_elf_backend_data (dynobj)->collect, &bh)))
5121 return FALSE;
5122 h = (struct elf_link_hash_entry *) bh;
5123 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
5124 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
5125 h->type = STT_OBJECT;
5126 h->verinfo.vertree = t;
5128 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5129 return FALSE;
5131 def.vd_version = VER_DEF_CURRENT;
5132 def.vd_flags = 0;
5133 if (t->globals.list == NULL
5134 && t->locals.list == NULL
5135 && ! t->used)
5136 def.vd_flags |= VER_FLG_WEAK;
5137 def.vd_ndx = t->vernum + 1;
5138 def.vd_cnt = cdeps + 1;
5139 def.vd_hash = bfd_elf_hash (t->name);
5140 def.vd_aux = sizeof (Elf_External_Verdef);
5141 def.vd_next = 0;
5142 if (t->next != NULL)
5143 def.vd_next = (sizeof (Elf_External_Verdef)
5144 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5146 _bfd_elf_swap_verdef_out (output_bfd, &def,
5147 (Elf_External_Verdef *) p);
5148 p += sizeof (Elf_External_Verdef);
5150 defaux.vda_name = h->dynstr_index;
5151 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5152 h->dynstr_index);
5153 defaux.vda_next = 0;
5154 if (t->deps != NULL)
5155 defaux.vda_next = sizeof (Elf_External_Verdaux);
5156 t->name_indx = defaux.vda_name;
5158 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5159 (Elf_External_Verdaux *) p);
5160 p += sizeof (Elf_External_Verdaux);
5162 for (n = t->deps; n != NULL; n = n->next)
5164 if (n->version_needed == NULL)
5166 /* This can happen if there was an error in the
5167 version script. */
5168 defaux.vda_name = 0;
5170 else
5172 defaux.vda_name = n->version_needed->name_indx;
5173 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5174 defaux.vda_name);
5176 if (n->next == NULL)
5177 defaux.vda_next = 0;
5178 else
5179 defaux.vda_next = sizeof (Elf_External_Verdaux);
5181 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5182 (Elf_External_Verdaux *) p);
5183 p += sizeof (Elf_External_Verdaux);
5187 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5188 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5189 return FALSE;
5191 elf_tdata (output_bfd)->cverdefs = cdefs;
5194 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5196 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5197 return FALSE;
5199 else if (info->flags & DF_BIND_NOW)
5201 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5202 return FALSE;
5205 if (info->flags_1)
5207 if (info->executable)
5208 info->flags_1 &= ~ (DF_1_INITFIRST
5209 | DF_1_NODELETE
5210 | DF_1_NOOPEN);
5211 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5212 return FALSE;
5215 /* Work out the size of the version reference section. */
5217 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5218 BFD_ASSERT (s != NULL);
5220 struct elf_find_verdep_info sinfo;
5222 sinfo.output_bfd = output_bfd;
5223 sinfo.info = info;
5224 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5225 if (sinfo.vers == 0)
5226 sinfo.vers = 1;
5227 sinfo.failed = FALSE;
5229 elf_link_hash_traverse (elf_hash_table (info),
5230 _bfd_elf_link_find_version_dependencies,
5231 &sinfo);
5233 if (elf_tdata (output_bfd)->verref == NULL)
5234 _bfd_strip_section_from_output (info, s);
5235 else
5237 Elf_Internal_Verneed *t;
5238 unsigned int size;
5239 unsigned int crefs;
5240 bfd_byte *p;
5242 /* Build the version definition section. */
5243 size = 0;
5244 crefs = 0;
5245 for (t = elf_tdata (output_bfd)->verref;
5246 t != NULL;
5247 t = t->vn_nextref)
5249 Elf_Internal_Vernaux *a;
5251 size += sizeof (Elf_External_Verneed);
5252 ++crefs;
5253 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5254 size += sizeof (Elf_External_Vernaux);
5257 s->size = size;
5258 s->contents = bfd_alloc (output_bfd, s->size);
5259 if (s->contents == NULL)
5260 return FALSE;
5262 p = s->contents;
5263 for (t = elf_tdata (output_bfd)->verref;
5264 t != NULL;
5265 t = t->vn_nextref)
5267 unsigned int caux;
5268 Elf_Internal_Vernaux *a;
5269 bfd_size_type indx;
5271 caux = 0;
5272 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5273 ++caux;
5275 t->vn_version = VER_NEED_CURRENT;
5276 t->vn_cnt = caux;
5277 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5278 elf_dt_name (t->vn_bfd) != NULL
5279 ? elf_dt_name (t->vn_bfd)
5280 : basename (t->vn_bfd->filename),
5281 FALSE);
5282 if (indx == (bfd_size_type) -1)
5283 return FALSE;
5284 t->vn_file = indx;
5285 t->vn_aux = sizeof (Elf_External_Verneed);
5286 if (t->vn_nextref == NULL)
5287 t->vn_next = 0;
5288 else
5289 t->vn_next = (sizeof (Elf_External_Verneed)
5290 + caux * sizeof (Elf_External_Vernaux));
5292 _bfd_elf_swap_verneed_out (output_bfd, t,
5293 (Elf_External_Verneed *) p);
5294 p += sizeof (Elf_External_Verneed);
5296 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5298 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5299 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5300 a->vna_nodename, FALSE);
5301 if (indx == (bfd_size_type) -1)
5302 return FALSE;
5303 a->vna_name = indx;
5304 if (a->vna_nextptr == NULL)
5305 a->vna_next = 0;
5306 else
5307 a->vna_next = sizeof (Elf_External_Vernaux);
5309 _bfd_elf_swap_vernaux_out (output_bfd, a,
5310 (Elf_External_Vernaux *) p);
5311 p += sizeof (Elf_External_Vernaux);
5315 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5316 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5317 return FALSE;
5319 elf_tdata (output_bfd)->cverrefs = crefs;
5323 /* Assign dynsym indicies. In a shared library we generate a
5324 section symbol for each output section, which come first.
5325 Next come all of the back-end allocated local dynamic syms,
5326 followed by the rest of the global symbols. */
5328 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5330 /* Work out the size of the symbol version section. */
5331 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5332 BFD_ASSERT (s != NULL);
5333 if (dynsymcount == 0
5334 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
5336 _bfd_strip_section_from_output (info, s);
5337 /* The DYNSYMCOUNT might have changed if we were going to
5338 output a dynamic symbol table entry for S. */
5339 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
5341 else
5343 s->size = dynsymcount * sizeof (Elf_External_Versym);
5344 s->contents = bfd_zalloc (output_bfd, s->size);
5345 if (s->contents == NULL)
5346 return FALSE;
5348 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5349 return FALSE;
5352 /* Set the size of the .dynsym and .hash sections. We counted
5353 the number of dynamic symbols in elf_link_add_object_symbols.
5354 We will build the contents of .dynsym and .hash when we build
5355 the final symbol table, because until then we do not know the
5356 correct value to give the symbols. We built the .dynstr
5357 section as we went along in elf_link_add_object_symbols. */
5358 s = bfd_get_section_by_name (dynobj, ".dynsym");
5359 BFD_ASSERT (s != NULL);
5360 s->size = dynsymcount * bed->s->sizeof_sym;
5361 s->contents = bfd_alloc (output_bfd, s->size);
5362 if (s->contents == NULL && s->size != 0)
5363 return FALSE;
5365 if (dynsymcount != 0)
5367 Elf_Internal_Sym isym;
5369 /* The first entry in .dynsym is a dummy symbol. */
5370 isym.st_value = 0;
5371 isym.st_size = 0;
5372 isym.st_name = 0;
5373 isym.st_info = 0;
5374 isym.st_other = 0;
5375 isym.st_shndx = 0;
5376 bed->s->swap_symbol_out (output_bfd, &isym, s->contents, 0);
5379 /* Compute the size of the hashing table. As a side effect this
5380 computes the hash values for all the names we export. */
5381 bucketcount = compute_bucket_count (info);
5383 s = bfd_get_section_by_name (dynobj, ".hash");
5384 BFD_ASSERT (s != NULL);
5385 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5386 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5387 s->contents = bfd_zalloc (output_bfd, s->size);
5388 if (s->contents == NULL)
5389 return FALSE;
5391 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5392 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5393 s->contents + hash_entry_size);
5395 elf_hash_table (info)->bucketcount = bucketcount;
5397 s = bfd_get_section_by_name (dynobj, ".dynstr");
5398 BFD_ASSERT (s != NULL);
5400 elf_finalize_dynstr (output_bfd, info);
5402 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5404 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5405 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5406 return FALSE;
5409 return TRUE;
5412 /* Final phase of ELF linker. */
5414 /* A structure we use to avoid passing large numbers of arguments. */
5416 struct elf_final_link_info
5418 /* General link information. */
5419 struct bfd_link_info *info;
5420 /* Output BFD. */
5421 bfd *output_bfd;
5422 /* Symbol string table. */
5423 struct bfd_strtab_hash *symstrtab;
5424 /* .dynsym section. */
5425 asection *dynsym_sec;
5426 /* .hash section. */
5427 asection *hash_sec;
5428 /* symbol version section (.gnu.version). */
5429 asection *symver_sec;
5430 /* Buffer large enough to hold contents of any section. */
5431 bfd_byte *contents;
5432 /* Buffer large enough to hold external relocs of any section. */
5433 void *external_relocs;
5434 /* Buffer large enough to hold internal relocs of any section. */
5435 Elf_Internal_Rela *internal_relocs;
5436 /* Buffer large enough to hold external local symbols of any input
5437 BFD. */
5438 bfd_byte *external_syms;
5439 /* And a buffer for symbol section indices. */
5440 Elf_External_Sym_Shndx *locsym_shndx;
5441 /* Buffer large enough to hold internal local symbols of any input
5442 BFD. */
5443 Elf_Internal_Sym *internal_syms;
5444 /* Array large enough to hold a symbol index for each local symbol
5445 of any input BFD. */
5446 long *indices;
5447 /* Array large enough to hold a section pointer for each local
5448 symbol of any input BFD. */
5449 asection **sections;
5450 /* Buffer to hold swapped out symbols. */
5451 bfd_byte *symbuf;
5452 /* And one for symbol section indices. */
5453 Elf_External_Sym_Shndx *symshndxbuf;
5454 /* Number of swapped out symbols in buffer. */
5455 size_t symbuf_count;
5456 /* Number of symbols which fit in symbuf. */
5457 size_t symbuf_size;
5458 /* And same for symshndxbuf. */
5459 size_t shndxbuf_size;
5462 /* This struct is used to pass information to elf_link_output_extsym. */
5464 struct elf_outext_info
5466 bfd_boolean failed;
5467 bfd_boolean localsyms;
5468 struct elf_final_link_info *finfo;
5471 /* When performing a relocatable link, the input relocations are
5472 preserved. But, if they reference global symbols, the indices
5473 referenced must be updated. Update all the relocations in
5474 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5476 static void
5477 elf_link_adjust_relocs (bfd *abfd,
5478 Elf_Internal_Shdr *rel_hdr,
5479 unsigned int count,
5480 struct elf_link_hash_entry **rel_hash)
5482 unsigned int i;
5483 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5484 bfd_byte *erela;
5485 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5486 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5487 bfd_vma r_type_mask;
5488 int r_sym_shift;
5490 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5492 swap_in = bed->s->swap_reloc_in;
5493 swap_out = bed->s->swap_reloc_out;
5495 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5497 swap_in = bed->s->swap_reloca_in;
5498 swap_out = bed->s->swap_reloca_out;
5500 else
5501 abort ();
5503 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5504 abort ();
5506 if (bed->s->arch_size == 32)
5508 r_type_mask = 0xff;
5509 r_sym_shift = 8;
5511 else
5513 r_type_mask = 0xffffffff;
5514 r_sym_shift = 32;
5517 erela = rel_hdr->contents;
5518 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5520 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5521 unsigned int j;
5523 if (*rel_hash == NULL)
5524 continue;
5526 BFD_ASSERT ((*rel_hash)->indx >= 0);
5528 (*swap_in) (abfd, erela, irela);
5529 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5530 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5531 | (irela[j].r_info & r_type_mask));
5532 (*swap_out) (abfd, irela, erela);
5536 struct elf_link_sort_rela
5538 union {
5539 bfd_vma offset;
5540 bfd_vma sym_mask;
5541 } u;
5542 enum elf_reloc_type_class type;
5543 /* We use this as an array of size int_rels_per_ext_rel. */
5544 Elf_Internal_Rela rela[1];
5547 static int
5548 elf_link_sort_cmp1 (const void *A, const void *B)
5550 const struct elf_link_sort_rela *a = A;
5551 const struct elf_link_sort_rela *b = B;
5552 int relativea, relativeb;
5554 relativea = a->type == reloc_class_relative;
5555 relativeb = b->type == reloc_class_relative;
5557 if (relativea < relativeb)
5558 return 1;
5559 if (relativea > relativeb)
5560 return -1;
5561 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5562 return -1;
5563 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5564 return 1;
5565 if (a->rela->r_offset < b->rela->r_offset)
5566 return -1;
5567 if (a->rela->r_offset > b->rela->r_offset)
5568 return 1;
5569 return 0;
5572 static int
5573 elf_link_sort_cmp2 (const void *A, const void *B)
5575 const struct elf_link_sort_rela *a = A;
5576 const struct elf_link_sort_rela *b = B;
5577 int copya, copyb;
5579 if (a->u.offset < b->u.offset)
5580 return -1;
5581 if (a->u.offset > b->u.offset)
5582 return 1;
5583 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5584 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5585 if (copya < copyb)
5586 return -1;
5587 if (copya > copyb)
5588 return 1;
5589 if (a->rela->r_offset < b->rela->r_offset)
5590 return -1;
5591 if (a->rela->r_offset > b->rela->r_offset)
5592 return 1;
5593 return 0;
5596 static size_t
5597 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5599 asection *reldyn;
5600 bfd_size_type count, size;
5601 size_t i, ret, sort_elt, ext_size;
5602 bfd_byte *sort, *s_non_relative, *p;
5603 struct elf_link_sort_rela *sq;
5604 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5605 int i2e = bed->s->int_rels_per_ext_rel;
5606 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5607 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5608 struct bfd_link_order *lo;
5609 bfd_vma r_sym_mask;
5611 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5612 if (reldyn == NULL || reldyn->size == 0)
5614 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
5615 if (reldyn == NULL || reldyn->size == 0)
5616 return 0;
5617 ext_size = bed->s->sizeof_rel;
5618 swap_in = bed->s->swap_reloc_in;
5619 swap_out = bed->s->swap_reloc_out;
5621 else
5623 ext_size = bed->s->sizeof_rela;
5624 swap_in = bed->s->swap_reloca_in;
5625 swap_out = bed->s->swap_reloca_out;
5627 count = reldyn->size / ext_size;
5629 size = 0;
5630 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5631 if (lo->type == bfd_indirect_link_order)
5633 asection *o = lo->u.indirect.section;
5634 size += o->size;
5637 if (size != reldyn->size)
5638 return 0;
5640 sort_elt = (sizeof (struct elf_link_sort_rela)
5641 + (i2e - 1) * sizeof (Elf_Internal_Rela));
5642 sort = bfd_zmalloc (sort_elt * count);
5643 if (sort == NULL)
5645 (*info->callbacks->warning)
5646 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
5647 return 0;
5650 if (bed->s->arch_size == 32)
5651 r_sym_mask = ~(bfd_vma) 0xff;
5652 else
5653 r_sym_mask = ~(bfd_vma) 0xffffffff;
5655 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5656 if (lo->type == bfd_indirect_link_order)
5658 bfd_byte *erel, *erelend;
5659 asection *o = lo->u.indirect.section;
5661 erel = o->contents;
5662 erelend = o->contents + o->size;
5663 p = sort + o->output_offset / ext_size * sort_elt;
5664 while (erel < erelend)
5666 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5667 (*swap_in) (abfd, erel, s->rela);
5668 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
5669 s->u.sym_mask = r_sym_mask;
5670 p += sort_elt;
5671 erel += ext_size;
5675 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
5677 for (i = 0, p = sort; i < count; i++, p += sort_elt)
5679 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5680 if (s->type != reloc_class_relative)
5681 break;
5683 ret = i;
5684 s_non_relative = p;
5686 sq = (struct elf_link_sort_rela *) s_non_relative;
5687 for (; i < count; i++, p += sort_elt)
5689 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
5690 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
5691 sq = sp;
5692 sp->u.offset = sq->rela->r_offset;
5695 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
5697 for (lo = reldyn->link_order_head; lo != NULL; lo = lo->next)
5698 if (lo->type == bfd_indirect_link_order)
5700 bfd_byte *erel, *erelend;
5701 asection *o = lo->u.indirect.section;
5703 erel = o->contents;
5704 erelend = o->contents + o->size;
5705 p = sort + o->output_offset / ext_size * sort_elt;
5706 while (erel < erelend)
5708 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
5709 (*swap_out) (abfd, s->rela, erel);
5710 p += sort_elt;
5711 erel += ext_size;
5715 free (sort);
5716 *psec = reldyn;
5717 return ret;
5720 /* Flush the output symbols to the file. */
5722 static bfd_boolean
5723 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
5724 const struct elf_backend_data *bed)
5726 if (finfo->symbuf_count > 0)
5728 Elf_Internal_Shdr *hdr;
5729 file_ptr pos;
5730 bfd_size_type amt;
5732 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5733 pos = hdr->sh_offset + hdr->sh_size;
5734 amt = finfo->symbuf_count * bed->s->sizeof_sym;
5735 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
5736 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
5737 return FALSE;
5739 hdr->sh_size += amt;
5740 finfo->symbuf_count = 0;
5743 return TRUE;
5746 /* Add a symbol to the output symbol table. */
5748 static bfd_boolean
5749 elf_link_output_sym (struct elf_final_link_info *finfo,
5750 const char *name,
5751 Elf_Internal_Sym *elfsym,
5752 asection *input_sec,
5753 struct elf_link_hash_entry *h)
5755 bfd_byte *dest;
5756 Elf_External_Sym_Shndx *destshndx;
5757 bfd_boolean (*output_symbol_hook)
5758 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
5759 struct elf_link_hash_entry *);
5760 const struct elf_backend_data *bed;
5762 bed = get_elf_backend_data (finfo->output_bfd);
5763 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
5764 if (output_symbol_hook != NULL)
5766 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
5767 return FALSE;
5770 if (name == NULL || *name == '\0')
5771 elfsym->st_name = 0;
5772 else if (input_sec->flags & SEC_EXCLUDE)
5773 elfsym->st_name = 0;
5774 else
5776 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5777 name, TRUE, FALSE);
5778 if (elfsym->st_name == (unsigned long) -1)
5779 return FALSE;
5782 if (finfo->symbuf_count >= finfo->symbuf_size)
5784 if (! elf_link_flush_output_syms (finfo, bed))
5785 return FALSE;
5788 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
5789 destshndx = finfo->symshndxbuf;
5790 if (destshndx != NULL)
5792 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
5794 bfd_size_type amt;
5796 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
5797 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
5798 if (destshndx == NULL)
5799 return FALSE;
5800 memset ((char *) destshndx + amt, 0, amt);
5801 finfo->shndxbuf_size *= 2;
5803 destshndx += bfd_get_symcount (finfo->output_bfd);
5806 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
5807 finfo->symbuf_count += 1;
5808 bfd_get_symcount (finfo->output_bfd) += 1;
5810 return TRUE;
5813 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
5814 allowing an unsatisfied unversioned symbol in the DSO to match a
5815 versioned symbol that would normally require an explicit version.
5816 We also handle the case that a DSO references a hidden symbol
5817 which may be satisfied by a versioned symbol in another DSO. */
5819 static bfd_boolean
5820 elf_link_check_versioned_symbol (struct bfd_link_info *info,
5821 const struct elf_backend_data *bed,
5822 struct elf_link_hash_entry *h)
5824 bfd *abfd;
5825 struct elf_link_loaded_list *loaded;
5827 if (!is_elf_hash_table (info->hash))
5828 return FALSE;
5830 switch (h->root.type)
5832 default:
5833 abfd = NULL;
5834 break;
5836 case bfd_link_hash_undefined:
5837 case bfd_link_hash_undefweak:
5838 abfd = h->root.u.undef.abfd;
5839 if ((abfd->flags & DYNAMIC) == 0
5840 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
5841 return FALSE;
5842 break;
5844 case bfd_link_hash_defined:
5845 case bfd_link_hash_defweak:
5846 abfd = h->root.u.def.section->owner;
5847 break;
5849 case bfd_link_hash_common:
5850 abfd = h->root.u.c.p->section->owner;
5851 break;
5853 BFD_ASSERT (abfd != NULL);
5855 for (loaded = elf_hash_table (info)->loaded;
5856 loaded != NULL;
5857 loaded = loaded->next)
5859 bfd *input;
5860 Elf_Internal_Shdr *hdr;
5861 bfd_size_type symcount;
5862 bfd_size_type extsymcount;
5863 bfd_size_type extsymoff;
5864 Elf_Internal_Shdr *versymhdr;
5865 Elf_Internal_Sym *isym;
5866 Elf_Internal_Sym *isymend;
5867 Elf_Internal_Sym *isymbuf;
5868 Elf_External_Versym *ever;
5869 Elf_External_Versym *extversym;
5871 input = loaded->abfd;
5873 /* We check each DSO for a possible hidden versioned definition. */
5874 if (input == abfd
5875 || (input->flags & DYNAMIC) == 0
5876 || elf_dynversym (input) == 0)
5877 continue;
5879 hdr = &elf_tdata (input)->dynsymtab_hdr;
5881 symcount = hdr->sh_size / bed->s->sizeof_sym;
5882 if (elf_bad_symtab (input))
5884 extsymcount = symcount;
5885 extsymoff = 0;
5887 else
5889 extsymcount = symcount - hdr->sh_info;
5890 extsymoff = hdr->sh_info;
5893 if (extsymcount == 0)
5894 continue;
5896 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
5897 NULL, NULL, NULL);
5898 if (isymbuf == NULL)
5899 return FALSE;
5901 /* Read in any version definitions. */
5902 versymhdr = &elf_tdata (input)->dynversym_hdr;
5903 extversym = bfd_malloc (versymhdr->sh_size);
5904 if (extversym == NULL)
5905 goto error_ret;
5907 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
5908 || (bfd_bread (extversym, versymhdr->sh_size, input)
5909 != versymhdr->sh_size))
5911 free (extversym);
5912 error_ret:
5913 free (isymbuf);
5914 return FALSE;
5917 ever = extversym + extsymoff;
5918 isymend = isymbuf + extsymcount;
5919 for (isym = isymbuf; isym < isymend; isym++, ever++)
5921 const char *name;
5922 Elf_Internal_Versym iver;
5923 unsigned short version_index;
5925 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
5926 || isym->st_shndx == SHN_UNDEF)
5927 continue;
5929 name = bfd_elf_string_from_elf_section (input,
5930 hdr->sh_link,
5931 isym->st_name);
5932 if (strcmp (name, h->root.root.string) != 0)
5933 continue;
5935 _bfd_elf_swap_versym_in (input, ever, &iver);
5937 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
5939 /* If we have a non-hidden versioned sym, then it should
5940 have provided a definition for the undefined sym. */
5941 abort ();
5944 version_index = iver.vs_vers & VERSYM_VERSION;
5945 if (version_index == 1 || version_index == 2)
5947 /* This is the base or first version. We can use it. */
5948 free (extversym);
5949 free (isymbuf);
5950 return TRUE;
5954 free (extversym);
5955 free (isymbuf);
5958 return FALSE;
5961 /* Add an external symbol to the symbol table. This is called from
5962 the hash table traversal routine. When generating a shared object,
5963 we go through the symbol table twice. The first time we output
5964 anything that might have been forced to local scope in a version
5965 script. The second time we output the symbols that are still
5966 global symbols. */
5968 static bfd_boolean
5969 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
5971 struct elf_outext_info *eoinfo = data;
5972 struct elf_final_link_info *finfo = eoinfo->finfo;
5973 bfd_boolean strip;
5974 Elf_Internal_Sym sym;
5975 asection *input_sec;
5976 const struct elf_backend_data *bed;
5978 if (h->root.type == bfd_link_hash_warning)
5980 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5981 if (h->root.type == bfd_link_hash_new)
5982 return TRUE;
5985 /* Decide whether to output this symbol in this pass. */
5986 if (eoinfo->localsyms)
5988 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5989 return TRUE;
5991 else
5993 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5994 return TRUE;
5997 bed = get_elf_backend_data (finfo->output_bfd);
5999 /* If we have an undefined symbol reference here then it must have
6000 come from a shared library that is being linked in. (Undefined
6001 references in regular files have already been handled). If we
6002 are reporting errors for this situation then do so now. */
6003 if (h->root.type == bfd_link_hash_undefined
6004 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
6005 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
6006 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6007 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6009 if (! ((*finfo->info->callbacks->undefined_symbol)
6010 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6011 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6013 eoinfo->failed = TRUE;
6014 return FALSE;
6018 /* We should also warn if a forced local symbol is referenced from
6019 shared libraries. */
6020 if (! finfo->info->relocatable
6021 && (! finfo->info->shared)
6022 && (h->elf_link_hash_flags
6023 & (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC | ELF_LINK_DYNAMIC_DEF | ELF_LINK_DYNAMIC_WEAK))
6024 == (ELF_LINK_FORCED_LOCAL | ELF_LINK_HASH_REF_DYNAMIC)
6025 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6027 (*_bfd_error_handler)
6028 (_("%s: %s symbol `%s' in %s is referenced by DSO"),
6029 bfd_get_filename (finfo->output_bfd),
6030 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6031 ? "internal"
6032 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6033 ? "hidden" : "local",
6034 h->root.root.string,
6035 bfd_archive_filename (h->root.u.def.section->owner));
6036 eoinfo->failed = TRUE;
6037 return FALSE;
6040 /* We don't want to output symbols that have never been mentioned by
6041 a regular file, or that we have been told to strip. However, if
6042 h->indx is set to -2, the symbol is used by a reloc and we must
6043 output it. */
6044 if (h->indx == -2)
6045 strip = FALSE;
6046 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
6047 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
6048 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
6049 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
6050 strip = TRUE;
6051 else if (finfo->info->strip == strip_all)
6052 strip = TRUE;
6053 else if (finfo->info->strip == strip_some
6054 && bfd_hash_lookup (finfo->info->keep_hash,
6055 h->root.root.string, FALSE, FALSE) == NULL)
6056 strip = TRUE;
6057 else if (finfo->info->strip_discarded
6058 && (h->root.type == bfd_link_hash_defined
6059 || h->root.type == bfd_link_hash_defweak)
6060 && elf_discarded_section (h->root.u.def.section))
6061 strip = TRUE;
6062 else
6063 strip = FALSE;
6065 /* If we're stripping it, and it's not a dynamic symbol, there's
6066 nothing else to do unless it is a forced local symbol. */
6067 if (strip
6068 && h->dynindx == -1
6069 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
6070 return TRUE;
6072 sym.st_value = 0;
6073 sym.st_size = h->size;
6074 sym.st_other = h->other;
6075 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
6076 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6077 else if (h->root.type == bfd_link_hash_undefweak
6078 || h->root.type == bfd_link_hash_defweak)
6079 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6080 else
6081 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6083 switch (h->root.type)
6085 default:
6086 case bfd_link_hash_new:
6087 case bfd_link_hash_warning:
6088 abort ();
6089 return FALSE;
6091 case bfd_link_hash_undefined:
6092 case bfd_link_hash_undefweak:
6093 input_sec = bfd_und_section_ptr;
6094 sym.st_shndx = SHN_UNDEF;
6095 break;
6097 case bfd_link_hash_defined:
6098 case bfd_link_hash_defweak:
6100 input_sec = h->root.u.def.section;
6101 if (input_sec->output_section != NULL)
6103 sym.st_shndx =
6104 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6105 input_sec->output_section);
6106 if (sym.st_shndx == SHN_BAD)
6108 char *sec_name = bfd_get_section_ident (input_sec);
6109 (*_bfd_error_handler)
6110 (_("%s: could not find output section %s for input section %s"),
6111 bfd_get_filename (finfo->output_bfd),
6112 input_sec->output_section->name,
6113 sec_name ? sec_name : input_sec->name);
6114 if (sec_name)
6115 free (sec_name);
6116 eoinfo->failed = TRUE;
6117 return FALSE;
6120 /* ELF symbols in relocatable files are section relative,
6121 but in nonrelocatable files they are virtual
6122 addresses. */
6123 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6124 if (! finfo->info->relocatable)
6126 sym.st_value += input_sec->output_section->vma;
6127 if (h->type == STT_TLS)
6129 /* STT_TLS symbols are relative to PT_TLS segment
6130 base. */
6131 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6132 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6136 else
6138 BFD_ASSERT (input_sec->owner == NULL
6139 || (input_sec->owner->flags & DYNAMIC) != 0);
6140 sym.st_shndx = SHN_UNDEF;
6141 input_sec = bfd_und_section_ptr;
6144 break;
6146 case bfd_link_hash_common:
6147 input_sec = h->root.u.c.p->section;
6148 sym.st_shndx = SHN_COMMON;
6149 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6150 break;
6152 case bfd_link_hash_indirect:
6153 /* These symbols are created by symbol versioning. They point
6154 to the decorated version of the name. For example, if the
6155 symbol foo@@GNU_1.2 is the default, which should be used when
6156 foo is used with no version, then we add an indirect symbol
6157 foo which points to foo@@GNU_1.2. We ignore these symbols,
6158 since the indirected symbol is already in the hash table. */
6159 return TRUE;
6162 /* Give the processor backend a chance to tweak the symbol value,
6163 and also to finish up anything that needs to be done for this
6164 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6165 forced local syms when non-shared is due to a historical quirk. */
6166 if ((h->dynindx != -1
6167 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
6168 && ((finfo->info->shared
6169 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6170 || h->root.type != bfd_link_hash_undefweak))
6171 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
6172 && elf_hash_table (finfo->info)->dynamic_sections_created)
6174 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6175 (finfo->output_bfd, finfo->info, h, &sym)))
6177 eoinfo->failed = TRUE;
6178 return FALSE;
6182 /* If we are marking the symbol as undefined, and there are no
6183 non-weak references to this symbol from a regular object, then
6184 mark the symbol as weak undefined; if there are non-weak
6185 references, mark the symbol as strong. We can't do this earlier,
6186 because it might not be marked as undefined until the
6187 finish_dynamic_symbol routine gets through with it. */
6188 if (sym.st_shndx == SHN_UNDEF
6189 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
6190 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6191 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6193 int bindtype;
6195 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
6196 bindtype = STB_GLOBAL;
6197 else
6198 bindtype = STB_WEAK;
6199 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6202 /* If a non-weak symbol with non-default visibility is not defined
6203 locally, it is a fatal error. */
6204 if (! finfo->info->relocatable
6205 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6206 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6207 && h->root.type == bfd_link_hash_undefined
6208 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
6210 (*_bfd_error_handler)
6211 (_("%s: %s symbol `%s' isn't defined"),
6212 bfd_get_filename (finfo->output_bfd),
6213 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6214 ? "protected"
6215 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6216 ? "internal" : "hidden",
6217 h->root.root.string);
6218 eoinfo->failed = TRUE;
6219 return FALSE;
6222 /* If this symbol should be put in the .dynsym section, then put it
6223 there now. We already know the symbol index. We also fill in
6224 the entry in the .hash section. */
6225 if (h->dynindx != -1
6226 && elf_hash_table (finfo->info)->dynamic_sections_created)
6228 size_t bucketcount;
6229 size_t bucket;
6230 size_t hash_entry_size;
6231 bfd_byte *bucketpos;
6232 bfd_vma chain;
6233 bfd_byte *esym;
6235 sym.st_name = h->dynstr_index;
6236 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6237 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6239 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6240 bucket = h->elf_hash_value % bucketcount;
6241 hash_entry_size
6242 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6243 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6244 + (bucket + 2) * hash_entry_size);
6245 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6246 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6247 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6248 ((bfd_byte *) finfo->hash_sec->contents
6249 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6251 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6253 Elf_Internal_Versym iversym;
6254 Elf_External_Versym *eversym;
6256 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
6258 if (h->verinfo.verdef == NULL)
6259 iversym.vs_vers = 0;
6260 else
6261 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6263 else
6265 if (h->verinfo.vertree == NULL)
6266 iversym.vs_vers = 1;
6267 else
6268 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6271 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
6272 iversym.vs_vers |= VERSYM_HIDDEN;
6274 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6275 eversym += h->dynindx;
6276 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6280 /* If we're stripping it, then it was just a dynamic symbol, and
6281 there's nothing else to do. */
6282 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6283 return TRUE;
6285 h->indx = bfd_get_symcount (finfo->output_bfd);
6287 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6289 eoinfo->failed = TRUE;
6290 return FALSE;
6293 return TRUE;
6296 /* Return TRUE if special handling is done for relocs in SEC against
6297 symbols defined in discarded sections. */
6299 static bfd_boolean
6300 elf_section_ignore_discarded_relocs (asection *sec)
6302 const struct elf_backend_data *bed;
6304 switch (sec->sec_info_type)
6306 case ELF_INFO_TYPE_STABS:
6307 case ELF_INFO_TYPE_EH_FRAME:
6308 return TRUE;
6309 default:
6310 break;
6313 bed = get_elf_backend_data (sec->owner);
6314 if (bed->elf_backend_ignore_discarded_relocs != NULL
6315 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6316 return TRUE;
6318 return FALSE;
6321 /* Return TRUE if we should complain about a reloc in SEC against a
6322 symbol defined in a discarded section. */
6324 static bfd_boolean
6325 elf_section_complain_discarded (asection *sec)
6327 if (strncmp (".stab", sec->name, 5) == 0
6328 && (!sec->name[5] ||
6329 (sec->name[5] == '.' && ISDIGIT (sec->name[6]))))
6330 return FALSE;
6332 if (strcmp (".eh_frame", sec->name) == 0)
6333 return FALSE;
6335 if (strcmp (".gcc_except_table", sec->name) == 0)
6336 return FALSE;
6338 if (strcmp (".PARISC.unwind", sec->name) == 0)
6339 return FALSE;
6341 return TRUE;
6344 /* Find a match between a section and a member of a section group. */
6346 static asection *
6347 match_group_member (asection *sec, asection *group)
6349 asection *first = elf_next_in_group (group);
6350 asection *s = first;
6352 while (s != NULL)
6354 if (bfd_elf_match_symbols_in_sections (s, sec))
6355 return s;
6357 if (s == first)
6358 break;
6361 return NULL;
6364 /* Link an input file into the linker output file. This function
6365 handles all the sections and relocations of the input file at once.
6366 This is so that we only have to read the local symbols once, and
6367 don't have to keep them in memory. */
6369 static bfd_boolean
6370 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6372 bfd_boolean (*relocate_section)
6373 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6374 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6375 bfd *output_bfd;
6376 Elf_Internal_Shdr *symtab_hdr;
6377 size_t locsymcount;
6378 size_t extsymoff;
6379 Elf_Internal_Sym *isymbuf;
6380 Elf_Internal_Sym *isym;
6381 Elf_Internal_Sym *isymend;
6382 long *pindex;
6383 asection **ppsection;
6384 asection *o;
6385 const struct elf_backend_data *bed;
6386 bfd_boolean emit_relocs;
6387 struct elf_link_hash_entry **sym_hashes;
6389 output_bfd = finfo->output_bfd;
6390 bed = get_elf_backend_data (output_bfd);
6391 relocate_section = bed->elf_backend_relocate_section;
6393 /* If this is a dynamic object, we don't want to do anything here:
6394 we don't want the local symbols, and we don't want the section
6395 contents. */
6396 if ((input_bfd->flags & DYNAMIC) != 0)
6397 return TRUE;
6399 emit_relocs = (finfo->info->relocatable
6400 || finfo->info->emitrelocations
6401 || bed->elf_backend_emit_relocs);
6403 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6404 if (elf_bad_symtab (input_bfd))
6406 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6407 extsymoff = 0;
6409 else
6411 locsymcount = symtab_hdr->sh_info;
6412 extsymoff = symtab_hdr->sh_info;
6415 /* Read the local symbols. */
6416 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6417 if (isymbuf == NULL && locsymcount != 0)
6419 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6420 finfo->internal_syms,
6421 finfo->external_syms,
6422 finfo->locsym_shndx);
6423 if (isymbuf == NULL)
6424 return FALSE;
6427 /* Find local symbol sections and adjust values of symbols in
6428 SEC_MERGE sections. Write out those local symbols we know are
6429 going into the output file. */
6430 isymend = isymbuf + locsymcount;
6431 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6432 isym < isymend;
6433 isym++, pindex++, ppsection++)
6435 asection *isec;
6436 const char *name;
6437 Elf_Internal_Sym osym;
6439 *pindex = -1;
6441 if (elf_bad_symtab (input_bfd))
6443 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6445 *ppsection = NULL;
6446 continue;
6450 if (isym->st_shndx == SHN_UNDEF)
6451 isec = bfd_und_section_ptr;
6452 else if (isym->st_shndx < SHN_LORESERVE
6453 || isym->st_shndx > SHN_HIRESERVE)
6455 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6456 if (isec
6457 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6458 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6459 isym->st_value =
6460 _bfd_merged_section_offset (output_bfd, &isec,
6461 elf_section_data (isec)->sec_info,
6462 isym->st_value);
6464 else if (isym->st_shndx == SHN_ABS)
6465 isec = bfd_abs_section_ptr;
6466 else if (isym->st_shndx == SHN_COMMON)
6467 isec = bfd_com_section_ptr;
6468 else
6470 /* Who knows? */
6471 isec = NULL;
6474 *ppsection = isec;
6476 /* Don't output the first, undefined, symbol. */
6477 if (ppsection == finfo->sections)
6478 continue;
6480 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6482 /* We never output section symbols. Instead, we use the
6483 section symbol of the corresponding section in the output
6484 file. */
6485 continue;
6488 /* If we are stripping all symbols, we don't want to output this
6489 one. */
6490 if (finfo->info->strip == strip_all)
6491 continue;
6493 /* If we are discarding all local symbols, we don't want to
6494 output this one. If we are generating a relocatable output
6495 file, then some of the local symbols may be required by
6496 relocs; we output them below as we discover that they are
6497 needed. */
6498 if (finfo->info->discard == discard_all)
6499 continue;
6501 /* If this symbol is defined in a section which we are
6502 discarding, we don't need to keep it, but note that
6503 linker_mark is only reliable for sections that have contents.
6504 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
6505 as well as linker_mark. */
6506 if ((isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6507 && isec != NULL
6508 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
6509 || (! finfo->info->relocatable
6510 && (isec->flags & SEC_EXCLUDE) != 0)))
6511 continue;
6513 /* Get the name of the symbol. */
6514 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6515 isym->st_name);
6516 if (name == NULL)
6517 return FALSE;
6519 /* See if we are discarding symbols with this name. */
6520 if ((finfo->info->strip == strip_some
6521 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6522 == NULL))
6523 || (((finfo->info->discard == discard_sec_merge
6524 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6525 || finfo->info->discard == discard_l)
6526 && bfd_is_local_label_name (input_bfd, name)))
6527 continue;
6529 /* If we get here, we are going to output this symbol. */
6531 osym = *isym;
6533 /* Adjust the section index for the output file. */
6534 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6535 isec->output_section);
6536 if (osym.st_shndx == SHN_BAD)
6537 return FALSE;
6539 *pindex = bfd_get_symcount (output_bfd);
6541 /* ELF symbols in relocatable files are section relative, but
6542 in executable files they are virtual addresses. Note that
6543 this code assumes that all ELF sections have an associated
6544 BFD section with a reasonable value for output_offset; below
6545 we assume that they also have a reasonable value for
6546 output_section. Any special sections must be set up to meet
6547 these requirements. */
6548 osym.st_value += isec->output_offset;
6549 if (! finfo->info->relocatable)
6551 osym.st_value += isec->output_section->vma;
6552 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
6554 /* STT_TLS symbols are relative to PT_TLS segment base. */
6555 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6556 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6560 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
6561 return FALSE;
6564 /* Relocate the contents of each section. */
6565 sym_hashes = elf_sym_hashes (input_bfd);
6566 for (o = input_bfd->sections; o != NULL; o = o->next)
6568 bfd_byte *contents;
6570 if (! o->linker_mark)
6572 /* This section was omitted from the link. */
6573 continue;
6576 if ((o->flags & SEC_HAS_CONTENTS) == 0
6577 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
6578 continue;
6580 if ((o->flags & SEC_LINKER_CREATED) != 0)
6582 /* Section was created by _bfd_elf_link_create_dynamic_sections
6583 or somesuch. */
6584 continue;
6587 /* Get the contents of the section. They have been cached by a
6588 relaxation routine. Note that o is a section in an input
6589 file, so the contents field will not have been set by any of
6590 the routines which work on output files. */
6591 if (elf_section_data (o)->this_hdr.contents != NULL)
6592 contents = elf_section_data (o)->this_hdr.contents;
6593 else
6595 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
6597 contents = finfo->contents;
6598 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
6599 return FALSE;
6602 if ((o->flags & SEC_RELOC) != 0)
6604 Elf_Internal_Rela *internal_relocs;
6605 bfd_vma r_type_mask;
6606 int r_sym_shift;
6608 /* Get the swapped relocs. */
6609 internal_relocs
6610 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
6611 finfo->internal_relocs, FALSE);
6612 if (internal_relocs == NULL
6613 && o->reloc_count > 0)
6614 return FALSE;
6616 if (bed->s->arch_size == 32)
6618 r_type_mask = 0xff;
6619 r_sym_shift = 8;
6621 else
6623 r_type_mask = 0xffffffff;
6624 r_sym_shift = 32;
6627 /* Run through the relocs looking for any against symbols
6628 from discarded sections and section symbols from
6629 removed link-once sections. Complain about relocs
6630 against discarded sections. Zero relocs against removed
6631 link-once sections. Preserve debug information as much
6632 as we can. */
6633 if (!elf_section_ignore_discarded_relocs (o))
6635 Elf_Internal_Rela *rel, *relend;
6636 bfd_boolean complain = elf_section_complain_discarded (o);
6638 rel = internal_relocs;
6639 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
6640 for ( ; rel < relend; rel++)
6642 unsigned long r_symndx = rel->r_info >> r_sym_shift;
6643 asection **ps, *sec;
6644 struct elf_link_hash_entry *h = NULL;
6645 const char *sym_name;
6647 if (r_symndx >= locsymcount
6648 || (elf_bad_symtab (input_bfd)
6649 && finfo->sections[r_symndx] == NULL))
6651 h = sym_hashes[r_symndx - extsymoff];
6652 while (h->root.type == bfd_link_hash_indirect
6653 || h->root.type == bfd_link_hash_warning)
6654 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6656 if (h->root.type != bfd_link_hash_defined
6657 && h->root.type != bfd_link_hash_defweak)
6658 continue;
6660 ps = &h->root.u.def.section;
6661 sym_name = h->root.root.string;
6663 else
6665 Elf_Internal_Sym *sym = isymbuf + r_symndx;
6666 ps = &finfo->sections[r_symndx];
6667 sym_name = bfd_elf_local_sym_name (input_bfd, sym);
6670 /* Complain if the definition comes from a
6671 discarded section. */
6672 if ((sec = *ps) != NULL && elf_discarded_section (sec))
6674 if ((o->flags & SEC_DEBUGGING) != 0)
6676 BFD_ASSERT (r_symndx != 0);
6678 /* Try to preserve debug information.
6679 FIXME: This is quite broken. Modifying
6680 the symbol here means we will be changing
6681 all uses of the symbol, not just those in
6682 debug sections. The only thing that makes
6683 this half reasonable is that debug sections
6684 tend to come after other sections. Of
6685 course, that doesn't help with globals.
6686 ??? All link-once sections of the same name
6687 ought to define the same set of symbols, so
6688 it would seem that globals ought to always
6689 be defined in the kept section. */
6690 if (sec->kept_section != NULL)
6692 asection *member;
6694 /* Check if it is a linkonce section or
6695 member of a comdat group. */
6696 if (elf_sec_group (sec) == NULL
6697 && sec->size == sec->kept_section->size)
6699 *ps = sec->kept_section;
6700 continue;
6702 else if (elf_sec_group (sec) != NULL
6703 && (member = match_group_member (sec, sec->kept_section))
6704 && sec->size == member->size)
6706 *ps = member;
6707 continue;
6711 else if (complain)
6713 char *r_sec
6714 = bfd_get_section_ident (o);
6715 char *d_sec
6716 = bfd_get_section_ident (sec);
6717 finfo->info->callbacks->error_handler
6718 (LD_DEFINITION_IN_DISCARDED_SECTION,
6719 _("`%T' referenced in section `%s' of %B: "
6720 "defined in discarded section `%s' of %B\n"),
6721 sym_name, sym_name,
6722 r_sec ? r_sec : o->name, input_bfd,
6723 d_sec ? d_sec : sec->name, sec->owner);
6724 if (r_sec)
6725 free (r_sec);
6726 if (d_sec)
6727 free (d_sec);
6730 /* Remove the symbol reference from the reloc, but
6731 don't kill the reloc completely. This is so that
6732 a zero value will be written into the section,
6733 which may have non-zero contents put there by the
6734 assembler. Zero in things like an eh_frame fde
6735 pc_begin allows stack unwinders to recognize the
6736 fde as bogus. */
6737 rel->r_info &= r_type_mask;
6738 rel->r_addend = 0;
6743 /* Relocate the section by invoking a back end routine.
6745 The back end routine is responsible for adjusting the
6746 section contents as necessary, and (if using Rela relocs
6747 and generating a relocatable output file) adjusting the
6748 reloc addend as necessary.
6750 The back end routine does not have to worry about setting
6751 the reloc address or the reloc symbol index.
6753 The back end routine is given a pointer to the swapped in
6754 internal symbols, and can access the hash table entries
6755 for the external symbols via elf_sym_hashes (input_bfd).
6757 When generating relocatable output, the back end routine
6758 must handle STB_LOCAL/STT_SECTION symbols specially. The
6759 output symbol is going to be a section symbol
6760 corresponding to the output section, which will require
6761 the addend to be adjusted. */
6763 if (! (*relocate_section) (output_bfd, finfo->info,
6764 input_bfd, o, contents,
6765 internal_relocs,
6766 isymbuf,
6767 finfo->sections))
6768 return FALSE;
6770 if (emit_relocs)
6772 Elf_Internal_Rela *irela;
6773 Elf_Internal_Rela *irelaend;
6774 bfd_vma last_offset;
6775 struct elf_link_hash_entry **rel_hash;
6776 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
6777 unsigned int next_erel;
6778 bfd_boolean (*reloc_emitter)
6779 (bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *);
6780 bfd_boolean rela_normal;
6782 input_rel_hdr = &elf_section_data (o)->rel_hdr;
6783 rela_normal = (bed->rela_normal
6784 && (input_rel_hdr->sh_entsize
6785 == bed->s->sizeof_rela));
6787 /* Adjust the reloc addresses and symbol indices. */
6789 irela = internal_relocs;
6790 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
6791 rel_hash = (elf_section_data (o->output_section)->rel_hashes
6792 + elf_section_data (o->output_section)->rel_count
6793 + elf_section_data (o->output_section)->rel_count2);
6794 last_offset = o->output_offset;
6795 if (!finfo->info->relocatable)
6796 last_offset += o->output_section->vma;
6797 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
6799 unsigned long r_symndx;
6800 asection *sec;
6801 Elf_Internal_Sym sym;
6803 if (next_erel == bed->s->int_rels_per_ext_rel)
6805 rel_hash++;
6806 next_erel = 0;
6809 irela->r_offset = _bfd_elf_section_offset (output_bfd,
6810 finfo->info, o,
6811 irela->r_offset);
6812 if (irela->r_offset >= (bfd_vma) -2)
6814 /* This is a reloc for a deleted entry or somesuch.
6815 Turn it into an R_*_NONE reloc, at the same
6816 offset as the last reloc. elf_eh_frame.c and
6817 elf_bfd_discard_info rely on reloc offsets
6818 being ordered. */
6819 irela->r_offset = last_offset;
6820 irela->r_info = 0;
6821 irela->r_addend = 0;
6822 continue;
6825 irela->r_offset += o->output_offset;
6827 /* Relocs in an executable have to be virtual addresses. */
6828 if (!finfo->info->relocatable)
6829 irela->r_offset += o->output_section->vma;
6831 last_offset = irela->r_offset;
6833 r_symndx = irela->r_info >> r_sym_shift;
6834 if (r_symndx == STN_UNDEF)
6835 continue;
6837 if (r_symndx >= locsymcount
6838 || (elf_bad_symtab (input_bfd)
6839 && finfo->sections[r_symndx] == NULL))
6841 struct elf_link_hash_entry *rh;
6842 unsigned long indx;
6844 /* This is a reloc against a global symbol. We
6845 have not yet output all the local symbols, so
6846 we do not know the symbol index of any global
6847 symbol. We set the rel_hash entry for this
6848 reloc to point to the global hash table entry
6849 for this symbol. The symbol index is then
6850 set at the end of elf_bfd_final_link. */
6851 indx = r_symndx - extsymoff;
6852 rh = elf_sym_hashes (input_bfd)[indx];
6853 while (rh->root.type == bfd_link_hash_indirect
6854 || rh->root.type == bfd_link_hash_warning)
6855 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
6857 /* Setting the index to -2 tells
6858 elf_link_output_extsym that this symbol is
6859 used by a reloc. */
6860 BFD_ASSERT (rh->indx < 0);
6861 rh->indx = -2;
6863 *rel_hash = rh;
6865 continue;
6868 /* This is a reloc against a local symbol. */
6870 *rel_hash = NULL;
6871 sym = isymbuf[r_symndx];
6872 sec = finfo->sections[r_symndx];
6873 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
6875 /* I suppose the backend ought to fill in the
6876 section of any STT_SECTION symbol against a
6877 processor specific section. */
6878 r_symndx = 0;
6879 if (bfd_is_abs_section (sec))
6881 else if (sec == NULL || sec->owner == NULL)
6883 bfd_set_error (bfd_error_bad_value);
6884 return FALSE;
6886 else
6888 asection *osec = sec->output_section;
6890 /* If we have discarded a section, the output
6891 section will be the absolute section. In
6892 case of discarded link-once and discarded
6893 SEC_MERGE sections, use the kept section. */
6894 if (bfd_is_abs_section (osec)
6895 && sec->kept_section != NULL
6896 && sec->kept_section->output_section != NULL)
6898 osec = sec->kept_section->output_section;
6899 irela->r_addend -= osec->vma;
6902 if (!bfd_is_abs_section (osec))
6904 r_symndx = osec->target_index;
6905 BFD_ASSERT (r_symndx != 0);
6909 /* Adjust the addend according to where the
6910 section winds up in the output section. */
6911 if (rela_normal)
6912 irela->r_addend += sec->output_offset;
6914 else
6916 if (finfo->indices[r_symndx] == -1)
6918 unsigned long shlink;
6919 const char *name;
6920 asection *osec;
6922 if (finfo->info->strip == strip_all)
6924 /* You can't do ld -r -s. */
6925 bfd_set_error (bfd_error_invalid_operation);
6926 return FALSE;
6929 /* This symbol was skipped earlier, but
6930 since it is needed by a reloc, we
6931 must output it now. */
6932 shlink = symtab_hdr->sh_link;
6933 name = (bfd_elf_string_from_elf_section
6934 (input_bfd, shlink, sym.st_name));
6935 if (name == NULL)
6936 return FALSE;
6938 osec = sec->output_section;
6939 sym.st_shndx =
6940 _bfd_elf_section_from_bfd_section (output_bfd,
6941 osec);
6942 if (sym.st_shndx == SHN_BAD)
6943 return FALSE;
6945 sym.st_value += sec->output_offset;
6946 if (! finfo->info->relocatable)
6948 sym.st_value += osec->vma;
6949 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
6951 /* STT_TLS symbols are relative to PT_TLS
6952 segment base. */
6953 BFD_ASSERT (elf_hash_table (finfo->info)
6954 ->tls_sec != NULL);
6955 sym.st_value -= (elf_hash_table (finfo->info)
6956 ->tls_sec->vma);
6960 finfo->indices[r_symndx]
6961 = bfd_get_symcount (output_bfd);
6963 if (! elf_link_output_sym (finfo, name, &sym, sec,
6964 NULL))
6965 return FALSE;
6968 r_symndx = finfo->indices[r_symndx];
6971 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
6972 | (irela->r_info & r_type_mask));
6975 /* Swap out the relocs. */
6976 if (bed->elf_backend_emit_relocs
6977 && !(finfo->info->relocatable
6978 || finfo->info->emitrelocations))
6979 reloc_emitter = bed->elf_backend_emit_relocs;
6980 else
6981 reloc_emitter = _bfd_elf_link_output_relocs;
6983 if (input_rel_hdr->sh_size != 0
6984 && ! (*reloc_emitter) (output_bfd, o, input_rel_hdr,
6985 internal_relocs))
6986 return FALSE;
6988 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
6989 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
6991 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
6992 * bed->s->int_rels_per_ext_rel);
6993 if (! (*reloc_emitter) (output_bfd, o, input_rel_hdr2,
6994 internal_relocs))
6995 return FALSE;
7000 /* Write out the modified section contents. */
7001 if (bed->elf_backend_write_section
7002 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7004 /* Section written out. */
7006 else switch (o->sec_info_type)
7008 case ELF_INFO_TYPE_STABS:
7009 if (! (_bfd_write_section_stabs
7010 (output_bfd,
7011 &elf_hash_table (finfo->info)->stab_info,
7012 o, &elf_section_data (o)->sec_info, contents)))
7013 return FALSE;
7014 break;
7015 case ELF_INFO_TYPE_MERGE:
7016 if (! _bfd_write_merged_section (output_bfd, o,
7017 elf_section_data (o)->sec_info))
7018 return FALSE;
7019 break;
7020 case ELF_INFO_TYPE_EH_FRAME:
7022 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7023 o, contents))
7024 return FALSE;
7026 break;
7027 default:
7029 if (! (o->flags & SEC_EXCLUDE)
7030 && ! bfd_set_section_contents (output_bfd, o->output_section,
7031 contents,
7032 (file_ptr) o->output_offset,
7033 o->size))
7034 return FALSE;
7036 break;
7040 return TRUE;
7043 /* Generate a reloc when linking an ELF file. This is a reloc
7044 requested by the linker, and does come from any input file. This
7045 is used to build constructor and destructor tables when linking
7046 with -Ur. */
7048 static bfd_boolean
7049 elf_reloc_link_order (bfd *output_bfd,
7050 struct bfd_link_info *info,
7051 asection *output_section,
7052 struct bfd_link_order *link_order)
7054 reloc_howto_type *howto;
7055 long indx;
7056 bfd_vma offset;
7057 bfd_vma addend;
7058 struct elf_link_hash_entry **rel_hash_ptr;
7059 Elf_Internal_Shdr *rel_hdr;
7060 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7061 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7062 bfd_byte *erel;
7063 unsigned int i;
7065 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7066 if (howto == NULL)
7068 bfd_set_error (bfd_error_bad_value);
7069 return FALSE;
7072 addend = link_order->u.reloc.p->addend;
7074 /* Figure out the symbol index. */
7075 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7076 + elf_section_data (output_section)->rel_count
7077 + elf_section_data (output_section)->rel_count2);
7078 if (link_order->type == bfd_section_reloc_link_order)
7080 indx = link_order->u.reloc.p->u.section->target_index;
7081 BFD_ASSERT (indx != 0);
7082 *rel_hash_ptr = NULL;
7084 else
7086 struct elf_link_hash_entry *h;
7088 /* Treat a reloc against a defined symbol as though it were
7089 actually against the section. */
7090 h = ((struct elf_link_hash_entry *)
7091 bfd_wrapped_link_hash_lookup (output_bfd, info,
7092 link_order->u.reloc.p->u.name,
7093 FALSE, FALSE, TRUE));
7094 if (h != NULL
7095 && (h->root.type == bfd_link_hash_defined
7096 || h->root.type == bfd_link_hash_defweak))
7098 asection *section;
7100 section = h->root.u.def.section;
7101 indx = section->output_section->target_index;
7102 *rel_hash_ptr = NULL;
7103 /* It seems that we ought to add the symbol value to the
7104 addend here, but in practice it has already been added
7105 because it was passed to constructor_callback. */
7106 addend += section->output_section->vma + section->output_offset;
7108 else if (h != NULL)
7110 /* Setting the index to -2 tells elf_link_output_extsym that
7111 this symbol is used by a reloc. */
7112 h->indx = -2;
7113 *rel_hash_ptr = h;
7114 indx = 0;
7116 else
7118 if (! ((*info->callbacks->unattached_reloc)
7119 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7120 return FALSE;
7121 indx = 0;
7125 /* If this is an inplace reloc, we must write the addend into the
7126 object file. */
7127 if (howto->partial_inplace && addend != 0)
7129 bfd_size_type size;
7130 bfd_reloc_status_type rstat;
7131 bfd_byte *buf;
7132 bfd_boolean ok;
7133 const char *sym_name;
7135 size = bfd_get_reloc_size (howto);
7136 buf = bfd_zmalloc (size);
7137 if (buf == NULL)
7138 return FALSE;
7139 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7140 switch (rstat)
7142 case bfd_reloc_ok:
7143 break;
7145 default:
7146 case bfd_reloc_outofrange:
7147 abort ();
7149 case bfd_reloc_overflow:
7150 if (link_order->type == bfd_section_reloc_link_order)
7151 sym_name = bfd_section_name (output_bfd,
7152 link_order->u.reloc.p->u.section);
7153 else
7154 sym_name = link_order->u.reloc.p->u.name;
7155 if (! ((*info->callbacks->reloc_overflow)
7156 (info, sym_name, howto->name, addend, NULL, NULL, 0)))
7158 free (buf);
7159 return FALSE;
7161 break;
7163 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7164 link_order->offset, size);
7165 free (buf);
7166 if (! ok)
7167 return FALSE;
7170 /* The address of a reloc is relative to the section in a
7171 relocatable file, and is a virtual address in an executable
7172 file. */
7173 offset = link_order->offset;
7174 if (! info->relocatable)
7175 offset += output_section->vma;
7177 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7179 irel[i].r_offset = offset;
7180 irel[i].r_info = 0;
7181 irel[i].r_addend = 0;
7183 if (bed->s->arch_size == 32)
7184 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7185 else
7186 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7188 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7189 erel = rel_hdr->contents;
7190 if (rel_hdr->sh_type == SHT_REL)
7192 erel += (elf_section_data (output_section)->rel_count
7193 * bed->s->sizeof_rel);
7194 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7196 else
7198 irel[0].r_addend = addend;
7199 erel += (elf_section_data (output_section)->rel_count
7200 * bed->s->sizeof_rela);
7201 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7204 ++elf_section_data (output_section)->rel_count;
7206 return TRUE;
7210 /* Get the output vma of the section pointed to by the sh_link field. */
7212 static bfd_vma
7213 elf_get_linked_section_vma (struct bfd_link_order *p)
7215 Elf_Internal_Shdr **elf_shdrp;
7216 asection *s;
7217 int elfsec;
7219 s = p->u.indirect.section;
7220 elf_shdrp = elf_elfsections (s->owner);
7221 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7222 elfsec = elf_shdrp[elfsec]->sh_link;
7223 s = elf_shdrp[elfsec]->bfd_section;
7224 return s->output_section->vma + s->output_offset;
7228 /* Compare two sections based on the locations of the sections they are
7229 linked to. Used by elf_fixup_link_order. */
7231 static int
7232 compare_link_order (const void * a, const void * b)
7234 bfd_vma apos;
7235 bfd_vma bpos;
7237 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7238 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7239 if (apos < bpos)
7240 return -1;
7241 return apos > bpos;
7245 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7246 order as their linked sections. Returns false if this could not be done
7247 because an output section includes both ordered and unordered
7248 sections. Ideally we'd do this in the linker proper. */
7250 static bfd_boolean
7251 elf_fixup_link_order (bfd *abfd, asection *o)
7253 int seen_linkorder;
7254 int seen_other;
7255 int n;
7256 struct bfd_link_order *p;
7257 bfd *sub;
7258 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7259 int elfsec;
7260 struct bfd_link_order **sections;
7261 asection *s;
7262 bfd_vma offset;
7264 seen_other = 0;
7265 seen_linkorder = 0;
7266 for (p = o->link_order_head; p != NULL; p = p->next)
7268 if (p->type == bfd_indirect_link_order
7269 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7270 == bfd_target_elf_flavour)
7271 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7273 s = p->u.indirect.section;
7274 elfsec = _bfd_elf_section_from_bfd_section (sub, s);
7275 if (elfsec != -1
7276 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7277 seen_linkorder++;
7278 else
7279 seen_other++;
7281 else
7282 seen_other++;
7285 if (!seen_linkorder)
7286 return TRUE;
7288 if (seen_other && seen_linkorder)
7290 (*_bfd_error_handler) (_("%s: has both ordered and unordered sections"),
7291 o->name);
7292 bfd_set_error (bfd_error_bad_value);
7293 return FALSE;
7296 sections = (struct bfd_link_order **)
7297 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7298 seen_linkorder = 0;
7300 for (p = o->link_order_head; p != NULL; p = p->next)
7302 sections[seen_linkorder++] = p;
7304 /* Sort the input sections in the order of their linked section. */
7305 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7306 compare_link_order);
7308 /* Change the offsets of the sections. */
7309 offset = 0;
7310 for (n = 0; n < seen_linkorder; n++)
7312 s = sections[n]->u.indirect.section;
7313 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7314 s->output_offset = offset;
7315 sections[n]->offset = offset;
7316 offset += sections[n]->size;
7319 return TRUE;
7323 /* Do the final step of an ELF link. */
7325 bfd_boolean
7326 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7328 bfd_boolean dynamic;
7329 bfd_boolean emit_relocs;
7330 bfd *dynobj;
7331 struct elf_final_link_info finfo;
7332 register asection *o;
7333 register struct bfd_link_order *p;
7334 register bfd *sub;
7335 bfd_size_type max_contents_size;
7336 bfd_size_type max_external_reloc_size;
7337 bfd_size_type max_internal_reloc_count;
7338 bfd_size_type max_sym_count;
7339 bfd_size_type max_sym_shndx_count;
7340 file_ptr off;
7341 Elf_Internal_Sym elfsym;
7342 unsigned int i;
7343 Elf_Internal_Shdr *symtab_hdr;
7344 Elf_Internal_Shdr *symtab_shndx_hdr;
7345 Elf_Internal_Shdr *symstrtab_hdr;
7346 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7347 struct elf_outext_info eoinfo;
7348 bfd_boolean merged;
7349 size_t relativecount = 0;
7350 asection *reldyn = 0;
7351 bfd_size_type amt;
7353 if (! is_elf_hash_table (info->hash))
7354 return FALSE;
7356 if (info->shared)
7357 abfd->flags |= DYNAMIC;
7359 dynamic = elf_hash_table (info)->dynamic_sections_created;
7360 dynobj = elf_hash_table (info)->dynobj;
7362 emit_relocs = (info->relocatable
7363 || info->emitrelocations
7364 || bed->elf_backend_emit_relocs);
7366 finfo.info = info;
7367 finfo.output_bfd = abfd;
7368 finfo.symstrtab = _bfd_elf_stringtab_init ();
7369 if (finfo.symstrtab == NULL)
7370 return FALSE;
7372 if (! dynamic)
7374 finfo.dynsym_sec = NULL;
7375 finfo.hash_sec = NULL;
7376 finfo.symver_sec = NULL;
7378 else
7380 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7381 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7382 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7383 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7384 /* Note that it is OK if symver_sec is NULL. */
7387 finfo.contents = NULL;
7388 finfo.external_relocs = NULL;
7389 finfo.internal_relocs = NULL;
7390 finfo.external_syms = NULL;
7391 finfo.locsym_shndx = NULL;
7392 finfo.internal_syms = NULL;
7393 finfo.indices = NULL;
7394 finfo.sections = NULL;
7395 finfo.symbuf = NULL;
7396 finfo.symshndxbuf = NULL;
7397 finfo.symbuf_count = 0;
7398 finfo.shndxbuf_size = 0;
7400 /* Count up the number of relocations we will output for each output
7401 section, so that we know the sizes of the reloc sections. We
7402 also figure out some maximum sizes. */
7403 max_contents_size = 0;
7404 max_external_reloc_size = 0;
7405 max_internal_reloc_count = 0;
7406 max_sym_count = 0;
7407 max_sym_shndx_count = 0;
7408 merged = FALSE;
7409 for (o = abfd->sections; o != NULL; o = o->next)
7411 struct bfd_elf_section_data *esdo = elf_section_data (o);
7412 o->reloc_count = 0;
7414 for (p = o->link_order_head; p != NULL; p = p->next)
7416 unsigned int reloc_count = 0;
7417 struct bfd_elf_section_data *esdi = NULL;
7418 unsigned int *rel_count1;
7420 if (p->type == bfd_section_reloc_link_order
7421 || p->type == bfd_symbol_reloc_link_order)
7422 reloc_count = 1;
7423 else if (p->type == bfd_indirect_link_order)
7425 asection *sec;
7427 sec = p->u.indirect.section;
7428 esdi = elf_section_data (sec);
7430 /* Mark all sections which are to be included in the
7431 link. This will normally be every section. We need
7432 to do this so that we can identify any sections which
7433 the linker has decided to not include. */
7434 sec->linker_mark = TRUE;
7436 if (sec->flags & SEC_MERGE)
7437 merged = TRUE;
7439 if (info->relocatable || info->emitrelocations)
7440 reloc_count = sec->reloc_count;
7441 else if (bed->elf_backend_count_relocs)
7443 Elf_Internal_Rela * relocs;
7445 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7446 info->keep_memory);
7448 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7450 if (elf_section_data (o)->relocs != relocs)
7451 free (relocs);
7454 if (sec->rawsize > max_contents_size)
7455 max_contents_size = sec->rawsize;
7456 if (sec->size > max_contents_size)
7457 max_contents_size = sec->size;
7459 /* We are interested in just local symbols, not all
7460 symbols. */
7461 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7462 && (sec->owner->flags & DYNAMIC) == 0)
7464 size_t sym_count;
7466 if (elf_bad_symtab (sec->owner))
7467 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7468 / bed->s->sizeof_sym);
7469 else
7470 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7472 if (sym_count > max_sym_count)
7473 max_sym_count = sym_count;
7475 if (sym_count > max_sym_shndx_count
7476 && elf_symtab_shndx (sec->owner) != 0)
7477 max_sym_shndx_count = sym_count;
7479 if ((sec->flags & SEC_RELOC) != 0)
7481 size_t ext_size;
7483 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7484 if (ext_size > max_external_reloc_size)
7485 max_external_reloc_size = ext_size;
7486 if (sec->reloc_count > max_internal_reloc_count)
7487 max_internal_reloc_count = sec->reloc_count;
7492 if (reloc_count == 0)
7493 continue;
7495 o->reloc_count += reloc_count;
7497 /* MIPS may have a mix of REL and RELA relocs on sections.
7498 To support this curious ABI we keep reloc counts in
7499 elf_section_data too. We must be careful to add the
7500 relocations from the input section to the right output
7501 count. FIXME: Get rid of one count. We have
7502 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7503 rel_count1 = &esdo->rel_count;
7504 if (esdi != NULL)
7506 bfd_boolean same_size;
7507 bfd_size_type entsize1;
7509 entsize1 = esdi->rel_hdr.sh_entsize;
7510 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7511 || entsize1 == bed->s->sizeof_rela);
7512 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7514 if (!same_size)
7515 rel_count1 = &esdo->rel_count2;
7517 if (esdi->rel_hdr2 != NULL)
7519 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7520 unsigned int alt_count;
7521 unsigned int *rel_count2;
7523 BFD_ASSERT (entsize2 != entsize1
7524 && (entsize2 == bed->s->sizeof_rel
7525 || entsize2 == bed->s->sizeof_rela));
7527 rel_count2 = &esdo->rel_count2;
7528 if (!same_size)
7529 rel_count2 = &esdo->rel_count;
7531 /* The following is probably too simplistic if the
7532 backend counts output relocs unusually. */
7533 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7534 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
7535 *rel_count2 += alt_count;
7536 reloc_count -= alt_count;
7539 *rel_count1 += reloc_count;
7542 if (o->reloc_count > 0)
7543 o->flags |= SEC_RELOC;
7544 else
7546 /* Explicitly clear the SEC_RELOC flag. The linker tends to
7547 set it (this is probably a bug) and if it is set
7548 assign_section_numbers will create a reloc section. */
7549 o->flags &=~ SEC_RELOC;
7552 /* If the SEC_ALLOC flag is not set, force the section VMA to
7553 zero. This is done in elf_fake_sections as well, but forcing
7554 the VMA to 0 here will ensure that relocs against these
7555 sections are handled correctly. */
7556 if ((o->flags & SEC_ALLOC) == 0
7557 && ! o->user_set_vma)
7558 o->vma = 0;
7561 if (! info->relocatable && merged)
7562 elf_link_hash_traverse (elf_hash_table (info),
7563 _bfd_elf_link_sec_merge_syms, abfd);
7565 /* Figure out the file positions for everything but the symbol table
7566 and the relocs. We set symcount to force assign_section_numbers
7567 to create a symbol table. */
7568 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
7569 BFD_ASSERT (! abfd->output_has_begun);
7570 if (! _bfd_elf_compute_section_file_positions (abfd, info))
7571 goto error_return;
7573 /* That created the reloc sections. Set their sizes, and assign
7574 them file positions, and allocate some buffers. */
7575 for (o = abfd->sections; o != NULL; o = o->next)
7577 if ((o->flags & SEC_RELOC) != 0)
7579 if (!(_bfd_elf_link_size_reloc_section
7580 (abfd, &elf_section_data (o)->rel_hdr, o)))
7581 goto error_return;
7583 if (elf_section_data (o)->rel_hdr2
7584 && !(_bfd_elf_link_size_reloc_section
7585 (abfd, elf_section_data (o)->rel_hdr2, o)))
7586 goto error_return;
7589 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
7590 to count upwards while actually outputting the relocations. */
7591 elf_section_data (o)->rel_count = 0;
7592 elf_section_data (o)->rel_count2 = 0;
7595 _bfd_elf_assign_file_positions_for_relocs (abfd);
7597 /* We have now assigned file positions for all the sections except
7598 .symtab and .strtab. We start the .symtab section at the current
7599 file position, and write directly to it. We build the .strtab
7600 section in memory. */
7601 bfd_get_symcount (abfd) = 0;
7602 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
7603 /* sh_name is set in prep_headers. */
7604 symtab_hdr->sh_type = SHT_SYMTAB;
7605 /* sh_flags, sh_addr and sh_size all start off zero. */
7606 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
7607 /* sh_link is set in assign_section_numbers. */
7608 /* sh_info is set below. */
7609 /* sh_offset is set just below. */
7610 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
7612 off = elf_tdata (abfd)->next_file_pos;
7613 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
7615 /* Note that at this point elf_tdata (abfd)->next_file_pos is
7616 incorrect. We do not yet know the size of the .symtab section.
7617 We correct next_file_pos below, after we do know the size. */
7619 /* Allocate a buffer to hold swapped out symbols. This is to avoid
7620 continuously seeking to the right position in the file. */
7621 if (! info->keep_memory || max_sym_count < 20)
7622 finfo.symbuf_size = 20;
7623 else
7624 finfo.symbuf_size = max_sym_count;
7625 amt = finfo.symbuf_size;
7626 amt *= bed->s->sizeof_sym;
7627 finfo.symbuf = bfd_malloc (amt);
7628 if (finfo.symbuf == NULL)
7629 goto error_return;
7630 if (elf_numsections (abfd) > SHN_LORESERVE)
7632 /* Wild guess at number of output symbols. realloc'd as needed. */
7633 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
7634 finfo.shndxbuf_size = amt;
7635 amt *= sizeof (Elf_External_Sym_Shndx);
7636 finfo.symshndxbuf = bfd_zmalloc (amt);
7637 if (finfo.symshndxbuf == NULL)
7638 goto error_return;
7641 /* Start writing out the symbol table. The first symbol is always a
7642 dummy symbol. */
7643 if (info->strip != strip_all
7644 || emit_relocs)
7646 elfsym.st_value = 0;
7647 elfsym.st_size = 0;
7648 elfsym.st_info = 0;
7649 elfsym.st_other = 0;
7650 elfsym.st_shndx = SHN_UNDEF;
7651 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
7652 NULL))
7653 goto error_return;
7656 #if 0
7657 /* Some standard ELF linkers do this, but we don't because it causes
7658 bootstrap comparison failures. */
7659 /* Output a file symbol for the output file as the second symbol.
7660 We output this even if we are discarding local symbols, although
7661 I'm not sure if this is correct. */
7662 elfsym.st_value = 0;
7663 elfsym.st_size = 0;
7664 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
7665 elfsym.st_other = 0;
7666 elfsym.st_shndx = SHN_ABS;
7667 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
7668 &elfsym, bfd_abs_section_ptr, NULL))
7669 goto error_return;
7670 #endif
7672 /* Output a symbol for each section. We output these even if we are
7673 discarding local symbols, since they are used for relocs. These
7674 symbols have no names. We store the index of each one in the
7675 index field of the section, so that we can find it again when
7676 outputting relocs. */
7677 if (info->strip != strip_all
7678 || emit_relocs)
7680 elfsym.st_size = 0;
7681 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
7682 elfsym.st_other = 0;
7683 for (i = 1; i < elf_numsections (abfd); i++)
7685 o = bfd_section_from_elf_index (abfd, i);
7686 if (o != NULL)
7687 o->target_index = bfd_get_symcount (abfd);
7688 elfsym.st_shndx = i;
7689 if (info->relocatable || o == NULL)
7690 elfsym.st_value = 0;
7691 else
7692 elfsym.st_value = o->vma;
7693 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
7694 goto error_return;
7695 if (i == SHN_LORESERVE - 1)
7696 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
7700 /* Allocate some memory to hold information read in from the input
7701 files. */
7702 if (max_contents_size != 0)
7704 finfo.contents = bfd_malloc (max_contents_size);
7705 if (finfo.contents == NULL)
7706 goto error_return;
7709 if (max_external_reloc_size != 0)
7711 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
7712 if (finfo.external_relocs == NULL)
7713 goto error_return;
7716 if (max_internal_reloc_count != 0)
7718 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
7719 amt *= sizeof (Elf_Internal_Rela);
7720 finfo.internal_relocs = bfd_malloc (amt);
7721 if (finfo.internal_relocs == NULL)
7722 goto error_return;
7725 if (max_sym_count != 0)
7727 amt = max_sym_count * bed->s->sizeof_sym;
7728 finfo.external_syms = bfd_malloc (amt);
7729 if (finfo.external_syms == NULL)
7730 goto error_return;
7732 amt = max_sym_count * sizeof (Elf_Internal_Sym);
7733 finfo.internal_syms = bfd_malloc (amt);
7734 if (finfo.internal_syms == NULL)
7735 goto error_return;
7737 amt = max_sym_count * sizeof (long);
7738 finfo.indices = bfd_malloc (amt);
7739 if (finfo.indices == NULL)
7740 goto error_return;
7742 amt = max_sym_count * sizeof (asection *);
7743 finfo.sections = bfd_malloc (amt);
7744 if (finfo.sections == NULL)
7745 goto error_return;
7748 if (max_sym_shndx_count != 0)
7750 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
7751 finfo.locsym_shndx = bfd_malloc (amt);
7752 if (finfo.locsym_shndx == NULL)
7753 goto error_return;
7756 if (elf_hash_table (info)->tls_sec)
7758 bfd_vma base, end = 0;
7759 asection *sec;
7761 for (sec = elf_hash_table (info)->tls_sec;
7762 sec && (sec->flags & SEC_THREAD_LOCAL);
7763 sec = sec->next)
7765 bfd_vma size = sec->size;
7767 if (size == 0 && (sec->flags & SEC_HAS_CONTENTS) == 0)
7769 struct bfd_link_order *o;
7771 for (o = sec->link_order_head; o != NULL; o = o->next)
7772 if (size < o->offset + o->size)
7773 size = o->offset + o->size;
7775 end = sec->vma + size;
7777 base = elf_hash_table (info)->tls_sec->vma;
7778 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
7779 elf_hash_table (info)->tls_size = end - base;
7782 /* Reorder SHF_LINK_ORDER sections. */
7783 for (o = abfd->sections; o != NULL; o = o->next)
7785 if (!elf_fixup_link_order (abfd, o))
7786 return FALSE;
7789 /* Since ELF permits relocations to be against local symbols, we
7790 must have the local symbols available when we do the relocations.
7791 Since we would rather only read the local symbols once, and we
7792 would rather not keep them in memory, we handle all the
7793 relocations for a single input file at the same time.
7795 Unfortunately, there is no way to know the total number of local
7796 symbols until we have seen all of them, and the local symbol
7797 indices precede the global symbol indices. This means that when
7798 we are generating relocatable output, and we see a reloc against
7799 a global symbol, we can not know the symbol index until we have
7800 finished examining all the local symbols to see which ones we are
7801 going to output. To deal with this, we keep the relocations in
7802 memory, and don't output them until the end of the link. This is
7803 an unfortunate waste of memory, but I don't see a good way around
7804 it. Fortunately, it only happens when performing a relocatable
7805 link, which is not the common case. FIXME: If keep_memory is set
7806 we could write the relocs out and then read them again; I don't
7807 know how bad the memory loss will be. */
7809 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
7810 sub->output_has_begun = FALSE;
7811 for (o = abfd->sections; o != NULL; o = o->next)
7813 for (p = o->link_order_head; p != NULL; p = p->next)
7815 if (p->type == bfd_indirect_link_order
7816 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
7817 == bfd_target_elf_flavour)
7818 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
7820 if (! sub->output_has_begun)
7822 if (! elf_link_input_bfd (&finfo, sub))
7823 goto error_return;
7824 sub->output_has_begun = TRUE;
7827 else if (p->type == bfd_section_reloc_link_order
7828 || p->type == bfd_symbol_reloc_link_order)
7830 if (! elf_reloc_link_order (abfd, info, o, p))
7831 goto error_return;
7833 else
7835 if (! _bfd_default_link_order (abfd, info, o, p))
7836 goto error_return;
7841 /* Output any global symbols that got converted to local in a
7842 version script or due to symbol visibility. We do this in a
7843 separate step since ELF requires all local symbols to appear
7844 prior to any global symbols. FIXME: We should only do this if
7845 some global symbols were, in fact, converted to become local.
7846 FIXME: Will this work correctly with the Irix 5 linker? */
7847 eoinfo.failed = FALSE;
7848 eoinfo.finfo = &finfo;
7849 eoinfo.localsyms = TRUE;
7850 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
7851 &eoinfo);
7852 if (eoinfo.failed)
7853 return FALSE;
7855 /* That wrote out all the local symbols. Finish up the symbol table
7856 with the global symbols. Even if we want to strip everything we
7857 can, we still need to deal with those global symbols that got
7858 converted to local in a version script. */
7860 /* The sh_info field records the index of the first non local symbol. */
7861 symtab_hdr->sh_info = bfd_get_symcount (abfd);
7863 if (dynamic
7864 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
7866 Elf_Internal_Sym sym;
7867 bfd_byte *dynsym = finfo.dynsym_sec->contents;
7868 long last_local = 0;
7870 /* Write out the section symbols for the output sections. */
7871 if (info->shared)
7873 asection *s;
7875 sym.st_size = 0;
7876 sym.st_name = 0;
7877 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
7878 sym.st_other = 0;
7880 for (s = abfd->sections; s != NULL; s = s->next)
7882 int indx;
7883 bfd_byte *dest;
7884 long dynindx;
7886 dynindx = elf_section_data (s)->dynindx;
7887 if (dynindx <= 0)
7888 continue;
7889 indx = elf_section_data (s)->this_idx;
7890 BFD_ASSERT (indx > 0);
7891 sym.st_shndx = indx;
7892 sym.st_value = s->vma;
7893 dest = dynsym + dynindx * bed->s->sizeof_sym;
7894 if (last_local < dynindx)
7895 last_local = dynindx;
7896 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
7900 /* Write out the local dynsyms. */
7901 if (elf_hash_table (info)->dynlocal)
7903 struct elf_link_local_dynamic_entry *e;
7904 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
7906 asection *s;
7907 bfd_byte *dest;
7909 sym.st_size = e->isym.st_size;
7910 sym.st_other = e->isym.st_other;
7912 /* Copy the internal symbol as is.
7913 Note that we saved a word of storage and overwrote
7914 the original st_name with the dynstr_index. */
7915 sym = e->isym;
7917 if (e->isym.st_shndx != SHN_UNDEF
7918 && (e->isym.st_shndx < SHN_LORESERVE
7919 || e->isym.st_shndx > SHN_HIRESERVE))
7921 s = bfd_section_from_elf_index (e->input_bfd,
7922 e->isym.st_shndx);
7924 sym.st_shndx =
7925 elf_section_data (s->output_section)->this_idx;
7926 sym.st_value = (s->output_section->vma
7927 + s->output_offset
7928 + e->isym.st_value);
7931 if (last_local < e->dynindx)
7932 last_local = e->dynindx;
7934 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
7935 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
7939 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
7940 last_local + 1;
7943 /* We get the global symbols from the hash table. */
7944 eoinfo.failed = FALSE;
7945 eoinfo.localsyms = FALSE;
7946 eoinfo.finfo = &finfo;
7947 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
7948 &eoinfo);
7949 if (eoinfo.failed)
7950 return FALSE;
7952 /* If backend needs to output some symbols not present in the hash
7953 table, do it now. */
7954 if (bed->elf_backend_output_arch_syms)
7956 typedef bfd_boolean (*out_sym_func)
7957 (void *, const char *, Elf_Internal_Sym *, asection *,
7958 struct elf_link_hash_entry *);
7960 if (! ((*bed->elf_backend_output_arch_syms)
7961 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
7962 return FALSE;
7965 /* Flush all symbols to the file. */
7966 if (! elf_link_flush_output_syms (&finfo, bed))
7967 return FALSE;
7969 /* Now we know the size of the symtab section. */
7970 off += symtab_hdr->sh_size;
7972 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
7973 if (symtab_shndx_hdr->sh_name != 0)
7975 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
7976 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
7977 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
7978 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
7979 symtab_shndx_hdr->sh_size = amt;
7981 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
7982 off, TRUE);
7984 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
7985 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
7986 return FALSE;
7990 /* Finish up and write out the symbol string table (.strtab)
7991 section. */
7992 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
7993 /* sh_name was set in prep_headers. */
7994 symstrtab_hdr->sh_type = SHT_STRTAB;
7995 symstrtab_hdr->sh_flags = 0;
7996 symstrtab_hdr->sh_addr = 0;
7997 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
7998 symstrtab_hdr->sh_entsize = 0;
7999 symstrtab_hdr->sh_link = 0;
8000 symstrtab_hdr->sh_info = 0;
8001 /* sh_offset is set just below. */
8002 symstrtab_hdr->sh_addralign = 1;
8004 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8005 elf_tdata (abfd)->next_file_pos = off;
8007 if (bfd_get_symcount (abfd) > 0)
8009 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8010 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8011 return FALSE;
8014 /* Adjust the relocs to have the correct symbol indices. */
8015 for (o = abfd->sections; o != NULL; o = o->next)
8017 if ((o->flags & SEC_RELOC) == 0)
8018 continue;
8020 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8021 elf_section_data (o)->rel_count,
8022 elf_section_data (o)->rel_hashes);
8023 if (elf_section_data (o)->rel_hdr2 != NULL)
8024 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8025 elf_section_data (o)->rel_count2,
8026 (elf_section_data (o)->rel_hashes
8027 + elf_section_data (o)->rel_count));
8029 /* Set the reloc_count field to 0 to prevent write_relocs from
8030 trying to swap the relocs out itself. */
8031 o->reloc_count = 0;
8034 if (dynamic && info->combreloc && dynobj != NULL)
8035 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8037 /* If we are linking against a dynamic object, or generating a
8038 shared library, finish up the dynamic linking information. */
8039 if (dynamic)
8041 bfd_byte *dyncon, *dynconend;
8043 /* Fix up .dynamic entries. */
8044 o = bfd_get_section_by_name (dynobj, ".dynamic");
8045 BFD_ASSERT (o != NULL);
8047 dyncon = o->contents;
8048 dynconend = o->contents + o->size;
8049 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8051 Elf_Internal_Dyn dyn;
8052 const char *name;
8053 unsigned int type;
8055 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8057 switch (dyn.d_tag)
8059 default:
8060 continue;
8061 case DT_NULL:
8062 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8064 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8066 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8067 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8068 default: continue;
8070 dyn.d_un.d_val = relativecount;
8071 relativecount = 0;
8072 break;
8074 continue;
8076 case DT_INIT:
8077 name = info->init_function;
8078 goto get_sym;
8079 case DT_FINI:
8080 name = info->fini_function;
8081 get_sym:
8083 struct elf_link_hash_entry *h;
8085 h = elf_link_hash_lookup (elf_hash_table (info), name,
8086 FALSE, FALSE, TRUE);
8087 if (h != NULL
8088 && (h->root.type == bfd_link_hash_defined
8089 || h->root.type == bfd_link_hash_defweak))
8091 dyn.d_un.d_val = h->root.u.def.value;
8092 o = h->root.u.def.section;
8093 if (o->output_section != NULL)
8094 dyn.d_un.d_val += (o->output_section->vma
8095 + o->output_offset);
8096 else
8098 /* The symbol is imported from another shared
8099 library and does not apply to this one. */
8100 dyn.d_un.d_val = 0;
8102 break;
8105 continue;
8107 case DT_PREINIT_ARRAYSZ:
8108 name = ".preinit_array";
8109 goto get_size;
8110 case DT_INIT_ARRAYSZ:
8111 name = ".init_array";
8112 goto get_size;
8113 case DT_FINI_ARRAYSZ:
8114 name = ".fini_array";
8115 get_size:
8116 o = bfd_get_section_by_name (abfd, name);
8117 if (o == NULL)
8119 (*_bfd_error_handler)
8120 (_("%s: could not find output section %s"),
8121 bfd_get_filename (abfd), name);
8122 goto error_return;
8124 if (o->size == 0)
8125 (*_bfd_error_handler)
8126 (_("warning: %s section has zero size"), name);
8127 dyn.d_un.d_val = o->size;
8128 break;
8130 case DT_PREINIT_ARRAY:
8131 name = ".preinit_array";
8132 goto get_vma;
8133 case DT_INIT_ARRAY:
8134 name = ".init_array";
8135 goto get_vma;
8136 case DT_FINI_ARRAY:
8137 name = ".fini_array";
8138 goto get_vma;
8140 case DT_HASH:
8141 name = ".hash";
8142 goto get_vma;
8143 case DT_STRTAB:
8144 name = ".dynstr";
8145 goto get_vma;
8146 case DT_SYMTAB:
8147 name = ".dynsym";
8148 goto get_vma;
8149 case DT_VERDEF:
8150 name = ".gnu.version_d";
8151 goto get_vma;
8152 case DT_VERNEED:
8153 name = ".gnu.version_r";
8154 goto get_vma;
8155 case DT_VERSYM:
8156 name = ".gnu.version";
8157 get_vma:
8158 o = bfd_get_section_by_name (abfd, name);
8159 if (o == NULL)
8161 (*_bfd_error_handler)
8162 (_("%s: could not find output section %s"),
8163 bfd_get_filename (abfd), name);
8164 goto error_return;
8166 dyn.d_un.d_ptr = o->vma;
8167 break;
8169 case DT_REL:
8170 case DT_RELA:
8171 case DT_RELSZ:
8172 case DT_RELASZ:
8173 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8174 type = SHT_REL;
8175 else
8176 type = SHT_RELA;
8177 dyn.d_un.d_val = 0;
8178 for (i = 1; i < elf_numsections (abfd); i++)
8180 Elf_Internal_Shdr *hdr;
8182 hdr = elf_elfsections (abfd)[i];
8183 if (hdr->sh_type == type
8184 && (hdr->sh_flags & SHF_ALLOC) != 0)
8186 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8187 dyn.d_un.d_val += hdr->sh_size;
8188 else
8190 if (dyn.d_un.d_val == 0
8191 || hdr->sh_addr < dyn.d_un.d_val)
8192 dyn.d_un.d_val = hdr->sh_addr;
8196 break;
8198 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8202 /* If we have created any dynamic sections, then output them. */
8203 if (dynobj != NULL)
8205 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8206 goto error_return;
8208 for (o = dynobj->sections; o != NULL; o = o->next)
8210 if ((o->flags & SEC_HAS_CONTENTS) == 0
8211 || o->size == 0
8212 || o->output_section == bfd_abs_section_ptr)
8213 continue;
8214 if ((o->flags & SEC_LINKER_CREATED) == 0)
8216 /* At this point, we are only interested in sections
8217 created by _bfd_elf_link_create_dynamic_sections. */
8218 continue;
8220 if (elf_hash_table (info)->stab_info.stabstr == o)
8221 continue;
8222 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8223 continue;
8224 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8225 != SHT_STRTAB)
8226 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8228 if (! bfd_set_section_contents (abfd, o->output_section,
8229 o->contents,
8230 (file_ptr) o->output_offset,
8231 o->size))
8232 goto error_return;
8234 else
8236 /* The contents of the .dynstr section are actually in a
8237 stringtab. */
8238 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8239 if (bfd_seek (abfd, off, SEEK_SET) != 0
8240 || ! _bfd_elf_strtab_emit (abfd,
8241 elf_hash_table (info)->dynstr))
8242 goto error_return;
8247 if (info->relocatable)
8249 bfd_boolean failed = FALSE;
8251 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8252 if (failed)
8253 goto error_return;
8256 /* If we have optimized stabs strings, output them. */
8257 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8259 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8260 goto error_return;
8263 if (info->eh_frame_hdr)
8265 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8266 goto error_return;
8269 if (finfo.symstrtab != NULL)
8270 _bfd_stringtab_free (finfo.symstrtab);
8271 if (finfo.contents != NULL)
8272 free (finfo.contents);
8273 if (finfo.external_relocs != NULL)
8274 free (finfo.external_relocs);
8275 if (finfo.internal_relocs != NULL)
8276 free (finfo.internal_relocs);
8277 if (finfo.external_syms != NULL)
8278 free (finfo.external_syms);
8279 if (finfo.locsym_shndx != NULL)
8280 free (finfo.locsym_shndx);
8281 if (finfo.internal_syms != NULL)
8282 free (finfo.internal_syms);
8283 if (finfo.indices != NULL)
8284 free (finfo.indices);
8285 if (finfo.sections != NULL)
8286 free (finfo.sections);
8287 if (finfo.symbuf != NULL)
8288 free (finfo.symbuf);
8289 if (finfo.symshndxbuf != NULL)
8290 free (finfo.symshndxbuf);
8291 for (o = abfd->sections; o != NULL; o = o->next)
8293 if ((o->flags & SEC_RELOC) != 0
8294 && elf_section_data (o)->rel_hashes != NULL)
8295 free (elf_section_data (o)->rel_hashes);
8298 elf_tdata (abfd)->linker = TRUE;
8300 return TRUE;
8302 error_return:
8303 if (finfo.symstrtab != NULL)
8304 _bfd_stringtab_free (finfo.symstrtab);
8305 if (finfo.contents != NULL)
8306 free (finfo.contents);
8307 if (finfo.external_relocs != NULL)
8308 free (finfo.external_relocs);
8309 if (finfo.internal_relocs != NULL)
8310 free (finfo.internal_relocs);
8311 if (finfo.external_syms != NULL)
8312 free (finfo.external_syms);
8313 if (finfo.locsym_shndx != NULL)
8314 free (finfo.locsym_shndx);
8315 if (finfo.internal_syms != NULL)
8316 free (finfo.internal_syms);
8317 if (finfo.indices != NULL)
8318 free (finfo.indices);
8319 if (finfo.sections != NULL)
8320 free (finfo.sections);
8321 if (finfo.symbuf != NULL)
8322 free (finfo.symbuf);
8323 if (finfo.symshndxbuf != NULL)
8324 free (finfo.symshndxbuf);
8325 for (o = abfd->sections; o != NULL; o = o->next)
8327 if ((o->flags & SEC_RELOC) != 0
8328 && elf_section_data (o)->rel_hashes != NULL)
8329 free (elf_section_data (o)->rel_hashes);
8332 return FALSE;
8335 /* Garbage collect unused sections. */
8337 /* The mark phase of garbage collection. For a given section, mark
8338 it and any sections in this section's group, and all the sections
8339 which define symbols to which it refers. */
8341 typedef asection * (*gc_mark_hook_fn)
8342 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8343 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8345 static bfd_boolean
8346 elf_gc_mark (struct bfd_link_info *info,
8347 asection *sec,
8348 gc_mark_hook_fn gc_mark_hook)
8350 bfd_boolean ret;
8351 asection *group_sec;
8353 sec->gc_mark = 1;
8355 /* Mark all the sections in the group. */
8356 group_sec = elf_section_data (sec)->next_in_group;
8357 if (group_sec && !group_sec->gc_mark)
8358 if (!elf_gc_mark (info, group_sec, gc_mark_hook))
8359 return FALSE;
8361 /* Look through the section relocs. */
8362 ret = TRUE;
8363 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8365 Elf_Internal_Rela *relstart, *rel, *relend;
8366 Elf_Internal_Shdr *symtab_hdr;
8367 struct elf_link_hash_entry **sym_hashes;
8368 size_t nlocsyms;
8369 size_t extsymoff;
8370 bfd *input_bfd = sec->owner;
8371 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8372 Elf_Internal_Sym *isym = NULL;
8373 int r_sym_shift;
8375 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8376 sym_hashes = elf_sym_hashes (input_bfd);
8378 /* Read the local symbols. */
8379 if (elf_bad_symtab (input_bfd))
8381 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8382 extsymoff = 0;
8384 else
8385 extsymoff = nlocsyms = symtab_hdr->sh_info;
8387 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8388 if (isym == NULL && nlocsyms != 0)
8390 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8391 NULL, NULL, NULL);
8392 if (isym == NULL)
8393 return FALSE;
8396 /* Read the relocations. */
8397 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8398 info->keep_memory);
8399 if (relstart == NULL)
8401 ret = FALSE;
8402 goto out1;
8404 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8406 if (bed->s->arch_size == 32)
8407 r_sym_shift = 8;
8408 else
8409 r_sym_shift = 32;
8411 for (rel = relstart; rel < relend; rel++)
8413 unsigned long r_symndx;
8414 asection *rsec;
8415 struct elf_link_hash_entry *h;
8417 r_symndx = rel->r_info >> r_sym_shift;
8418 if (r_symndx == 0)
8419 continue;
8421 if (r_symndx >= nlocsyms
8422 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8424 h = sym_hashes[r_symndx - extsymoff];
8425 while (h->root.type == bfd_link_hash_indirect
8426 || h->root.type == bfd_link_hash_warning)
8427 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8428 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8430 else
8432 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8435 if (rsec && !rsec->gc_mark)
8437 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8438 rsec->gc_mark = 1;
8439 else if (!elf_gc_mark (info, rsec, gc_mark_hook))
8441 ret = FALSE;
8442 goto out2;
8447 out2:
8448 if (elf_section_data (sec)->relocs != relstart)
8449 free (relstart);
8450 out1:
8451 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8453 if (! info->keep_memory)
8454 free (isym);
8455 else
8456 symtab_hdr->contents = (unsigned char *) isym;
8460 return ret;
8463 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8465 static bfd_boolean
8466 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *idxptr)
8468 int *idx = idxptr;
8470 if (h->root.type == bfd_link_hash_warning)
8471 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8473 if (h->dynindx != -1
8474 && ((h->root.type != bfd_link_hash_defined
8475 && h->root.type != bfd_link_hash_defweak)
8476 || h->root.u.def.section->gc_mark))
8477 h->dynindx = (*idx)++;
8479 return TRUE;
8482 /* The sweep phase of garbage collection. Remove all garbage sections. */
8484 typedef bfd_boolean (*gc_sweep_hook_fn)
8485 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8487 static bfd_boolean
8488 elf_gc_sweep (struct bfd_link_info *info, gc_sweep_hook_fn gc_sweep_hook)
8490 bfd *sub;
8492 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8494 asection *o;
8496 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8497 continue;
8499 for (o = sub->sections; o != NULL; o = o->next)
8501 /* Keep special sections. Keep .debug sections. */
8502 if ((o->flags & SEC_LINKER_CREATED)
8503 || (o->flags & SEC_DEBUGGING))
8504 o->gc_mark = 1;
8506 if (o->gc_mark)
8507 continue;
8509 /* Skip sweeping sections already excluded. */
8510 if (o->flags & SEC_EXCLUDE)
8511 continue;
8513 /* Since this is early in the link process, it is simple
8514 to remove a section from the output. */
8515 o->flags |= SEC_EXCLUDE;
8517 /* But we also have to update some of the relocation
8518 info we collected before. */
8519 if (gc_sweep_hook
8520 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
8522 Elf_Internal_Rela *internal_relocs;
8523 bfd_boolean r;
8525 internal_relocs
8526 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8527 info->keep_memory);
8528 if (internal_relocs == NULL)
8529 return FALSE;
8531 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8533 if (elf_section_data (o)->relocs != internal_relocs)
8534 free (internal_relocs);
8536 if (!r)
8537 return FALSE;
8542 /* Remove the symbols that were in the swept sections from the dynamic
8543 symbol table. GCFIXME: Anyone know how to get them out of the
8544 static symbol table as well? */
8546 int i = 0;
8548 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol, &i);
8550 elf_hash_table (info)->dynsymcount = i;
8553 return TRUE;
8556 /* Propagate collected vtable information. This is called through
8557 elf_link_hash_traverse. */
8559 static bfd_boolean
8560 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
8562 if (h->root.type == bfd_link_hash_warning)
8563 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8565 /* Those that are not vtables. */
8566 if (h->vtable_parent == NULL)
8567 return TRUE;
8569 /* Those vtables that do not have parents, we cannot merge. */
8570 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
8571 return TRUE;
8573 /* If we've already been done, exit. */
8574 if (h->vtable_entries_used && h->vtable_entries_used[-1])
8575 return TRUE;
8577 /* Make sure the parent's table is up to date. */
8578 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
8580 if (h->vtable_entries_used == NULL)
8582 /* None of this table's entries were referenced. Re-use the
8583 parent's table. */
8584 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
8585 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
8587 else
8589 size_t n;
8590 bfd_boolean *cu, *pu;
8592 /* Or the parent's entries into ours. */
8593 cu = h->vtable_entries_used;
8594 cu[-1] = TRUE;
8595 pu = h->vtable_parent->vtable_entries_used;
8596 if (pu != NULL)
8598 const struct elf_backend_data *bed;
8599 unsigned int log_file_align;
8601 bed = get_elf_backend_data (h->root.u.def.section->owner);
8602 log_file_align = bed->s->log_file_align;
8603 n = h->vtable_parent->vtable_entries_size >> log_file_align;
8604 while (n--)
8606 if (*pu)
8607 *cu = TRUE;
8608 pu++;
8609 cu++;
8614 return TRUE;
8617 static bfd_boolean
8618 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
8620 asection *sec;
8621 bfd_vma hstart, hend;
8622 Elf_Internal_Rela *relstart, *relend, *rel;
8623 const struct elf_backend_data *bed;
8624 unsigned int log_file_align;
8626 if (h->root.type == bfd_link_hash_warning)
8627 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8629 /* Take care of both those symbols that do not describe vtables as
8630 well as those that are not loaded. */
8631 if (h->vtable_parent == NULL)
8632 return TRUE;
8634 BFD_ASSERT (h->root.type == bfd_link_hash_defined
8635 || h->root.type == bfd_link_hash_defweak);
8637 sec = h->root.u.def.section;
8638 hstart = h->root.u.def.value;
8639 hend = hstart + h->size;
8641 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
8642 if (!relstart)
8643 return *(bfd_boolean *) okp = FALSE;
8644 bed = get_elf_backend_data (sec->owner);
8645 log_file_align = bed->s->log_file_align;
8647 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8649 for (rel = relstart; rel < relend; ++rel)
8650 if (rel->r_offset >= hstart && rel->r_offset < hend)
8652 /* If the entry is in use, do nothing. */
8653 if (h->vtable_entries_used
8654 && (rel->r_offset - hstart) < h->vtable_entries_size)
8656 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
8657 if (h->vtable_entries_used[entry])
8658 continue;
8660 /* Otherwise, kill it. */
8661 rel->r_offset = rel->r_info = rel->r_addend = 0;
8664 return TRUE;
8667 /* Mark sections containing dynamically referenced symbols. This is called
8668 through elf_link_hash_traverse. */
8670 static bfd_boolean
8671 elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h,
8672 void *okp ATTRIBUTE_UNUSED)
8674 if (h->root.type == bfd_link_hash_warning)
8675 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8677 if ((h->root.type == bfd_link_hash_defined
8678 || h->root.type == bfd_link_hash_defweak)
8679 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC))
8680 h->root.u.def.section->flags |= SEC_KEEP;
8682 return TRUE;
8685 /* Do mark and sweep of unused sections. */
8687 bfd_boolean
8688 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
8690 bfd_boolean ok = TRUE;
8691 bfd *sub;
8692 asection * (*gc_mark_hook)
8693 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8694 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
8696 if (!get_elf_backend_data (abfd)->can_gc_sections
8697 || info->relocatable
8698 || info->emitrelocations
8699 || info->shared
8700 || !is_elf_hash_table (info->hash))
8702 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
8703 return TRUE;
8706 /* Apply transitive closure to the vtable entry usage info. */
8707 elf_link_hash_traverse (elf_hash_table (info),
8708 elf_gc_propagate_vtable_entries_used,
8709 &ok);
8710 if (!ok)
8711 return FALSE;
8713 /* Kill the vtable relocations that were not used. */
8714 elf_link_hash_traverse (elf_hash_table (info),
8715 elf_gc_smash_unused_vtentry_relocs,
8716 &ok);
8717 if (!ok)
8718 return FALSE;
8720 /* Mark dynamically referenced symbols. */
8721 if (elf_hash_table (info)->dynamic_sections_created)
8722 elf_link_hash_traverse (elf_hash_table (info),
8723 elf_gc_mark_dynamic_ref_symbol,
8724 &ok);
8725 if (!ok)
8726 return FALSE;
8728 /* Grovel through relocs to find out who stays ... */
8729 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
8730 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8732 asection *o;
8734 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8735 continue;
8737 for (o = sub->sections; o != NULL; o = o->next)
8739 if (o->flags & SEC_KEEP)
8741 /* _bfd_elf_discard_section_eh_frame knows how to discard
8742 orphaned FDEs so don't mark sections referenced by the
8743 EH frame section. */
8744 if (strcmp (o->name, ".eh_frame") == 0)
8745 o->gc_mark = 1;
8746 else if (!elf_gc_mark (info, o, gc_mark_hook))
8747 return FALSE;
8752 /* ... and mark SEC_EXCLUDE for those that go. */
8753 if (!elf_gc_sweep (info, get_elf_backend_data (abfd)->gc_sweep_hook))
8754 return FALSE;
8756 return TRUE;
8759 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
8761 bfd_boolean
8762 bfd_elf_gc_record_vtinherit (bfd *abfd,
8763 asection *sec,
8764 struct elf_link_hash_entry *h,
8765 bfd_vma offset)
8767 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
8768 struct elf_link_hash_entry **search, *child;
8769 bfd_size_type extsymcount;
8770 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8771 char *sec_name;
8773 /* The sh_info field of the symtab header tells us where the
8774 external symbols start. We don't care about the local symbols at
8775 this point. */
8776 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
8777 if (!elf_bad_symtab (abfd))
8778 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
8780 sym_hashes = elf_sym_hashes (abfd);
8781 sym_hashes_end = sym_hashes + extsymcount;
8783 /* Hunt down the child symbol, which is in this section at the same
8784 offset as the relocation. */
8785 for (search = sym_hashes; search != sym_hashes_end; ++search)
8787 if ((child = *search) != NULL
8788 && (child->root.type == bfd_link_hash_defined
8789 || child->root.type == bfd_link_hash_defweak)
8790 && child->root.u.def.section == sec
8791 && child->root.u.def.value == offset)
8792 goto win;
8795 sec_name = bfd_get_section_ident (sec);
8796 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
8797 bfd_archive_filename (abfd),
8798 sec_name ? sec_name : sec->name,
8799 (unsigned long) offset);
8800 bfd_set_error (bfd_error_invalid_operation);
8801 return FALSE;
8803 win:
8804 if (!h)
8806 /* This *should* only be the absolute section. It could potentially
8807 be that someone has defined a non-global vtable though, which
8808 would be bad. It isn't worth paging in the local symbols to be
8809 sure though; that case should simply be handled by the assembler. */
8811 child->vtable_parent = (struct elf_link_hash_entry *) -1;
8813 else
8814 child->vtable_parent = h;
8816 return TRUE;
8819 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
8821 bfd_boolean
8822 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
8823 asection *sec ATTRIBUTE_UNUSED,
8824 struct elf_link_hash_entry *h,
8825 bfd_vma addend)
8827 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8828 unsigned int log_file_align = bed->s->log_file_align;
8830 if (addend >= h->vtable_entries_size)
8832 size_t size, bytes, file_align;
8833 bfd_boolean *ptr = h->vtable_entries_used;
8835 /* While the symbol is undefined, we have to be prepared to handle
8836 a zero size. */
8837 file_align = 1 << log_file_align;
8838 if (h->root.type == bfd_link_hash_undefined)
8839 size = addend + file_align;
8840 else
8842 size = h->size;
8843 if (addend >= size)
8845 /* Oops! We've got a reference past the defined end of
8846 the table. This is probably a bug -- shall we warn? */
8847 size = addend + file_align;
8850 size = (size + file_align - 1) & -file_align;
8852 /* Allocate one extra entry for use as a "done" flag for the
8853 consolidation pass. */
8854 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
8856 if (ptr)
8858 ptr = bfd_realloc (ptr - 1, bytes);
8860 if (ptr != NULL)
8862 size_t oldbytes;
8864 oldbytes = (((h->vtable_entries_size >> log_file_align) + 1)
8865 * sizeof (bfd_boolean));
8866 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
8869 else
8870 ptr = bfd_zmalloc (bytes);
8872 if (ptr == NULL)
8873 return FALSE;
8875 /* And arrange for that done flag to be at index -1. */
8876 h->vtable_entries_used = ptr + 1;
8877 h->vtable_entries_size = size;
8880 h->vtable_entries_used[addend >> log_file_align] = TRUE;
8882 return TRUE;
8885 struct alloc_got_off_arg {
8886 bfd_vma gotoff;
8887 unsigned int got_elt_size;
8890 /* We need a special top-level link routine to convert got reference counts
8891 to real got offsets. */
8893 static bfd_boolean
8894 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
8896 struct alloc_got_off_arg *gofarg = arg;
8898 if (h->root.type == bfd_link_hash_warning)
8899 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8901 if (h->got.refcount > 0)
8903 h->got.offset = gofarg->gotoff;
8904 gofarg->gotoff += gofarg->got_elt_size;
8906 else
8907 h->got.offset = (bfd_vma) -1;
8909 return TRUE;
8912 /* And an accompanying bit to work out final got entry offsets once
8913 we're done. Should be called from final_link. */
8915 bfd_boolean
8916 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
8917 struct bfd_link_info *info)
8919 bfd *i;
8920 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8921 bfd_vma gotoff;
8922 unsigned int got_elt_size = bed->s->arch_size / 8;
8923 struct alloc_got_off_arg gofarg;
8925 if (! is_elf_hash_table (info->hash))
8926 return FALSE;
8928 /* The GOT offset is relative to the .got section, but the GOT header is
8929 put into the .got.plt section, if the backend uses it. */
8930 if (bed->want_got_plt)
8931 gotoff = 0;
8932 else
8933 gotoff = bed->got_header_size;
8935 /* Do the local .got entries first. */
8936 for (i = info->input_bfds; i; i = i->link_next)
8938 bfd_signed_vma *local_got;
8939 bfd_size_type j, locsymcount;
8940 Elf_Internal_Shdr *symtab_hdr;
8942 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
8943 continue;
8945 local_got = elf_local_got_refcounts (i);
8946 if (!local_got)
8947 continue;
8949 symtab_hdr = &elf_tdata (i)->symtab_hdr;
8950 if (elf_bad_symtab (i))
8951 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
8952 else
8953 locsymcount = symtab_hdr->sh_info;
8955 for (j = 0; j < locsymcount; ++j)
8957 if (local_got[j] > 0)
8959 local_got[j] = gotoff;
8960 gotoff += got_elt_size;
8962 else
8963 local_got[j] = (bfd_vma) -1;
8967 /* Then the global .got entries. .plt refcounts are handled by
8968 adjust_dynamic_symbol */
8969 gofarg.gotoff = gotoff;
8970 gofarg.got_elt_size = got_elt_size;
8971 elf_link_hash_traverse (elf_hash_table (info),
8972 elf_gc_allocate_got_offsets,
8973 &gofarg);
8974 return TRUE;
8977 /* Many folk need no more in the way of final link than this, once
8978 got entry reference counting is enabled. */
8980 bfd_boolean
8981 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
8983 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
8984 return FALSE;
8986 /* Invoke the regular ELF backend linker to do all the work. */
8987 return bfd_elf_final_link (abfd, info);
8990 bfd_boolean
8991 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
8993 struct elf_reloc_cookie *rcookie = cookie;
8995 if (rcookie->bad_symtab)
8996 rcookie->rel = rcookie->rels;
8998 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9000 unsigned long r_symndx;
9002 if (! rcookie->bad_symtab)
9003 if (rcookie->rel->r_offset > offset)
9004 return FALSE;
9005 if (rcookie->rel->r_offset != offset)
9006 continue;
9008 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9009 if (r_symndx == SHN_UNDEF)
9010 return TRUE;
9012 if (r_symndx >= rcookie->locsymcount
9013 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9015 struct elf_link_hash_entry *h;
9017 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9019 while (h->root.type == bfd_link_hash_indirect
9020 || h->root.type == bfd_link_hash_warning)
9021 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9023 if ((h->root.type == bfd_link_hash_defined
9024 || h->root.type == bfd_link_hash_defweak)
9025 && elf_discarded_section (h->root.u.def.section))
9026 return TRUE;
9027 else
9028 return FALSE;
9030 else
9032 /* It's not a relocation against a global symbol,
9033 but it could be a relocation against a local
9034 symbol for a discarded section. */
9035 asection *isec;
9036 Elf_Internal_Sym *isym;
9038 /* Need to: get the symbol; get the section. */
9039 isym = &rcookie->locsyms[r_symndx];
9040 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9042 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9043 if (isec != NULL && elf_discarded_section (isec))
9044 return TRUE;
9047 return FALSE;
9049 return FALSE;
9052 /* Discard unneeded references to discarded sections.
9053 Returns TRUE if any section's size was changed. */
9054 /* This function assumes that the relocations are in sorted order,
9055 which is true for all known assemblers. */
9057 bfd_boolean
9058 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9060 struct elf_reloc_cookie cookie;
9061 asection *stab, *eh;
9062 Elf_Internal_Shdr *symtab_hdr;
9063 const struct elf_backend_data *bed;
9064 bfd *abfd;
9065 unsigned int count;
9066 bfd_boolean ret = FALSE;
9068 if (info->traditional_format
9069 || !is_elf_hash_table (info->hash))
9070 return FALSE;
9072 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9074 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9075 continue;
9077 bed = get_elf_backend_data (abfd);
9079 if ((abfd->flags & DYNAMIC) != 0)
9080 continue;
9082 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9083 if (info->relocatable
9084 || (eh != NULL
9085 && (eh->size == 0
9086 || bfd_is_abs_section (eh->output_section))))
9087 eh = NULL;
9089 stab = bfd_get_section_by_name (abfd, ".stab");
9090 if (stab != NULL
9091 && (stab->size == 0
9092 || bfd_is_abs_section (stab->output_section)
9093 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9094 stab = NULL;
9096 if (stab == NULL
9097 && eh == NULL
9098 && bed->elf_backend_discard_info == NULL)
9099 continue;
9101 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9102 cookie.abfd = abfd;
9103 cookie.sym_hashes = elf_sym_hashes (abfd);
9104 cookie.bad_symtab = elf_bad_symtab (abfd);
9105 if (cookie.bad_symtab)
9107 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9108 cookie.extsymoff = 0;
9110 else
9112 cookie.locsymcount = symtab_hdr->sh_info;
9113 cookie.extsymoff = symtab_hdr->sh_info;
9116 if (bed->s->arch_size == 32)
9117 cookie.r_sym_shift = 8;
9118 else
9119 cookie.r_sym_shift = 32;
9121 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9122 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9124 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9125 cookie.locsymcount, 0,
9126 NULL, NULL, NULL);
9127 if (cookie.locsyms == NULL)
9128 return FALSE;
9131 if (stab != NULL)
9133 cookie.rels = NULL;
9134 count = stab->reloc_count;
9135 if (count != 0)
9136 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9137 info->keep_memory);
9138 if (cookie.rels != NULL)
9140 cookie.rel = cookie.rels;
9141 cookie.relend = cookie.rels;
9142 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9143 if (_bfd_discard_section_stabs (abfd, stab,
9144 elf_section_data (stab)->sec_info,
9145 bfd_elf_reloc_symbol_deleted_p,
9146 &cookie))
9147 ret = TRUE;
9148 if (elf_section_data (stab)->relocs != cookie.rels)
9149 free (cookie.rels);
9153 if (eh != NULL)
9155 cookie.rels = NULL;
9156 count = eh->reloc_count;
9157 if (count != 0)
9158 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9159 info->keep_memory);
9160 cookie.rel = cookie.rels;
9161 cookie.relend = cookie.rels;
9162 if (cookie.rels != NULL)
9163 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9165 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9166 bfd_elf_reloc_symbol_deleted_p,
9167 &cookie))
9168 ret = TRUE;
9170 if (cookie.rels != NULL
9171 && elf_section_data (eh)->relocs != cookie.rels)
9172 free (cookie.rels);
9175 if (bed->elf_backend_discard_info != NULL
9176 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9177 ret = TRUE;
9179 if (cookie.locsyms != NULL
9180 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9182 if (! info->keep_memory)
9183 free (cookie.locsyms);
9184 else
9185 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9189 if (info->eh_frame_hdr
9190 && !info->relocatable
9191 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9192 ret = TRUE;
9194 return ret;
9197 struct already_linked_section
9199 asection *sec;
9200 asection *linked;
9203 /* Check if the member of a single member comdat group matches a
9204 linkonce section and vice versa. */
9205 static bfd_boolean
9206 try_match_symbols_in_sections
9207 (struct bfd_section_already_linked_hash_entry *h, void *info)
9209 struct bfd_section_already_linked *l;
9210 struct already_linked_section *s
9211 = (struct already_linked_section *) info;
9213 if (elf_sec_group (s->sec) == NULL)
9215 /* It is a linkonce section. Try to match it with the member of a
9216 single member comdat group. */
9217 for (l = h->entry; l != NULL; l = l->next)
9218 if ((l->sec->flags & SEC_GROUP))
9220 asection *first = elf_next_in_group (l->sec);
9222 if (first != NULL
9223 && elf_next_in_group (first) == first
9224 && bfd_elf_match_symbols_in_sections (first, s->sec))
9226 s->linked = first;
9227 return FALSE;
9231 else
9233 /* It is the member of a single member comdat group. Try to match
9234 it with a linkonce section. */
9235 for (l = h->entry; l != NULL; l = l->next)
9236 if ((l->sec->flags & SEC_GROUP) == 0
9237 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9238 && bfd_elf_match_symbols_in_sections (l->sec, s->sec))
9240 s->linked = l->sec;
9241 return FALSE;
9245 return TRUE;
9248 static bfd_boolean
9249 already_linked (asection *sec, asection *group)
9251 struct already_linked_section result;
9253 result.sec = sec;
9254 result.linked = NULL;
9256 bfd_section_already_linked_table_traverse
9257 (try_match_symbols_in_sections, &result);
9259 if (result.linked)
9261 sec->output_section = bfd_abs_section_ptr;
9262 sec->kept_section = result.linked;
9264 /* Also discard the group section. */
9265 if (group)
9266 group->output_section = bfd_abs_section_ptr;
9268 return TRUE;
9271 return FALSE;
9274 void
9275 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9277 flagword flags;
9278 const char *name;
9279 struct bfd_section_already_linked *l;
9280 struct bfd_section_already_linked_hash_entry *already_linked_list;
9281 asection *group;
9283 /* A single member comdat group section may be discarded by a
9284 linkonce section. See below. */
9285 if (sec->output_section == bfd_abs_section_ptr)
9286 return;
9288 flags = sec->flags;
9290 /* Check if it belongs to a section group. */
9291 group = elf_sec_group (sec);
9293 /* Return if it isn't a linkonce section nor a member of a group. A
9294 comdat group section also has SEC_LINK_ONCE set. */
9295 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9296 return;
9298 if (group)
9300 /* If this is the member of a single member comdat group, check if
9301 the group should be discarded. */
9302 if (elf_next_in_group (sec) == sec
9303 && (group->flags & SEC_LINK_ONCE) != 0)
9304 sec = group;
9305 else
9306 return;
9309 /* FIXME: When doing a relocatable link, we may have trouble
9310 copying relocations in other sections that refer to local symbols
9311 in the section being discarded. Those relocations will have to
9312 be converted somehow; as of this writing I'm not sure that any of
9313 the backends handle that correctly.
9315 It is tempting to instead not discard link once sections when
9316 doing a relocatable link (technically, they should be discarded
9317 whenever we are building constructors). However, that fails,
9318 because the linker winds up combining all the link once sections
9319 into a single large link once section, which defeats the purpose
9320 of having link once sections in the first place.
9322 Also, not merging link once sections in a relocatable link
9323 causes trouble for MIPS ELF, which relies on link once semantics
9324 to handle the .reginfo section correctly. */
9326 name = bfd_get_section_name (abfd, sec);
9328 already_linked_list = bfd_section_already_linked_table_lookup (name);
9330 for (l = already_linked_list->entry; l != NULL; l = l->next)
9332 /* We may have 3 different sections on the list: group section,
9333 comdat section and linkonce section. SEC may be a linkonce or
9334 group section. We match a group section with a group section,
9335 a linkonce section with a linkonce section, and ignore comdat
9336 section. */
9337 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9338 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9340 /* The section has already been linked. See if we should
9341 issue a warning. */
9342 switch (flags & SEC_LINK_DUPLICATES)
9344 default:
9345 abort ();
9347 case SEC_LINK_DUPLICATES_DISCARD:
9348 break;
9350 case SEC_LINK_DUPLICATES_ONE_ONLY:
9351 (*_bfd_error_handler)
9352 (_("%s: %s: warning: ignoring duplicate section `%s'\n"),
9353 bfd_archive_filename (abfd), name);
9354 break;
9356 case SEC_LINK_DUPLICATES_SAME_SIZE:
9357 if (sec->size != l->sec->size)
9358 (*_bfd_error_handler)
9359 (_("%s: %s: warning: duplicate section `%s' has different size\n"),
9360 bfd_archive_filename (abfd), name);
9361 break;
9364 /* Set the output_section field so that lang_add_section
9365 does not create a lang_input_section structure for this
9366 section. Since there might be a symbol in the section
9367 being discarded, we must retain a pointer to the section
9368 which we are really going to use. */
9369 sec->output_section = bfd_abs_section_ptr;
9370 sec->kept_section = l->sec;
9372 if (flags & SEC_GROUP)
9374 asection *first = elf_next_in_group (sec);
9375 asection *s = first;
9377 while (s != NULL)
9379 s->output_section = bfd_abs_section_ptr;
9380 /* Record which group discards it. */
9381 s->kept_section = l->sec;
9382 s = elf_next_in_group (s);
9383 /* These lists are circular. */
9384 if (s == first)
9385 break;
9389 return;
9393 if (group)
9395 /* If this is the member of a single member comdat group and the
9396 group hasn't be discarded, we check if it matches a linkonce
9397 section. We only record the discarded comdat group. Otherwise
9398 the undiscarded group will be discarded incorrectly later since
9399 itself has been recorded. */
9400 if (! already_linked (elf_next_in_group (sec), group))
9401 return;
9403 else
9404 /* There is no direct match. But for linkonce section, we should
9405 check if there is a match with comdat group member. We always
9406 record the linkonce section, discarded or not. */
9407 already_linked (sec, group);
9409 /* This is the first section with this name. Record it. */
9410 bfd_section_already_linked_table_insert (already_linked_list, sec);