1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
3 2005, 2006, 2007 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
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.
11
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.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
20
21 #include "sysdep.h"
22 #include "bfd.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
29 #include "objalloc.h"
30
31 /* Define a symbol in a dynamic linkage section. */
32
33 struct elf_link_hash_entry *
_bfd_elf_define_linkage_sym(bfd * abfd,struct bfd_link_info * info,asection * sec,const char * name)34 _bfd_elf_define_linkage_sym (bfd *abfd,
35 struct bfd_link_info *info,
36 asection *sec,
37 const char *name)
38 {
39 struct elf_link_hash_entry *h;
40 struct bfd_link_hash_entry *bh;
41 const struct elf_backend_data *bed;
42
43 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
44 if (h != NULL)
45 {
46 /* Zap symbol defined in an as-needed lib that wasn't linked.
47 This is a symptom of a larger problem: Absolute symbols
48 defined in shared libraries can't be overridden, because we
49 lose the link to the bfd which is via the symbol section. */
50 h->root.type = bfd_link_hash_new;
51 }
52
53 bh = &h->root;
54 if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
55 sec, 0, NULL, FALSE,
56 get_elf_backend_data (abfd)->collect,
57 &bh))
58 return NULL;
59 h = (struct elf_link_hash_entry *) bh;
60 h->def_regular = 1;
61 h->type = STT_OBJECT;
62 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
63
64 bed = get_elf_backend_data (abfd);
65 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
66 return h;
67 }
68
69 bfd_boolean
_bfd_elf_create_got_section(bfd * abfd,struct bfd_link_info * info)70 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
71 {
72 flagword flags;
73 asection *s;
74 struct elf_link_hash_entry *h;
75 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
76 int ptralign;
77
78 /* This function may be called more than once. */
79 s = bfd_get_section_by_name (abfd, ".got");
80 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
81 return TRUE;
82
83 switch (bed->s->arch_size)
84 {
85 case 32:
86 ptralign = 2;
87 break;
88
89 case 64:
90 ptralign = 3;
91 break;
92
93 default:
94 bfd_set_error (bfd_error_bad_value);
95 return FALSE;
96 }
97
98 flags = bed->dynamic_sec_flags;
99
100 s = bfd_make_section_with_flags (abfd, ".got", flags);
101 if (s == NULL
102 || !bfd_set_section_alignment (abfd, s, ptralign))
103 return FALSE;
104
105 if (bed->want_got_plt)
106 {
107 s = bfd_make_section_with_flags (abfd, ".got.plt", flags);
108 if (s == NULL
109 || !bfd_set_section_alignment (abfd, s, ptralign))
110 return FALSE;
111 }
112
113 if (bed->want_got_sym)
114 {
115 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
116 (or .got.plt) section. We don't do this in the linker script
117 because we don't want to define the symbol if we are not creating
118 a global offset table. */
119 h = _bfd_elf_define_linkage_sym (abfd, info, s, "_GLOBAL_OFFSET_TABLE_");
120 elf_hash_table (info)->hgot = h;
121 if (h == NULL)
122 return FALSE;
123 }
124
125 /* The first bit of the global offset table is the header. */
126 s->size += bed->got_header_size;
127
128 return TRUE;
129 }
130
131 /* Create a strtab to hold the dynamic symbol names. */
132 static bfd_boolean
_bfd_elf_link_create_dynstrtab(bfd * abfd,struct bfd_link_info * info)133 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
134 {
135 struct elf_link_hash_table *hash_table;
136
137 hash_table = elf_hash_table (info);
138 if (hash_table->dynobj == NULL)
139 hash_table->dynobj = abfd;
140
141 if (hash_table->dynstr == NULL)
142 {
143 hash_table->dynstr = _bfd_elf_strtab_init ();
144 if (hash_table->dynstr == NULL)
145 return FALSE;
146 }
147 return TRUE;
148 }
149
150 /* Create some sections which will be filled in with dynamic linking
151 information. ABFD is an input file which requires dynamic sections
152 to be created. The dynamic sections take up virtual memory space
153 when the final executable is run, so we need to create them before
154 addresses are assigned to the output sections. We work out the
155 actual contents and size of these sections later. */
156
157 bfd_boolean
_bfd_elf_link_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)158 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
159 {
160 flagword flags;
161 register asection *s;
162 const struct elf_backend_data *bed;
163
164 if (! is_elf_hash_table (info->hash))
165 return FALSE;
166
167 if (elf_hash_table (info)->dynamic_sections_created)
168 return TRUE;
169
170 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
171 return FALSE;
172
173 abfd = elf_hash_table (info)->dynobj;
174 bed = get_elf_backend_data (abfd);
175
176 flags = bed->dynamic_sec_flags;
177
178 /* A dynamically linked executable has a .interp section, but a
179 shared library does not. */
180 if (info->executable)
181 {
182 s = bfd_make_section_with_flags (abfd, ".interp",
183 flags | SEC_READONLY);
184 if (s == NULL)
185 return FALSE;
186 }
187
188 /* Create sections to hold version informations. These are removed
189 if they are not needed. */
190 s = bfd_make_section_with_flags (abfd, ".gnu.version_d",
191 flags | SEC_READONLY);
192 if (s == NULL
193 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
194 return FALSE;
195
196 s = bfd_make_section_with_flags (abfd, ".gnu.version",
197 flags | SEC_READONLY);
198 if (s == NULL
199 || ! bfd_set_section_alignment (abfd, s, 1))
200 return FALSE;
201
202 s = bfd_make_section_with_flags (abfd, ".gnu.version_r",
203 flags | SEC_READONLY);
204 if (s == NULL
205 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
206 return FALSE;
207
208 s = bfd_make_section_with_flags (abfd, ".dynsym",
209 flags | SEC_READONLY);
210 if (s == NULL
211 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
212 return FALSE;
213
214 s = bfd_make_section_with_flags (abfd, ".dynstr",
215 flags | SEC_READONLY);
216 if (s == NULL)
217 return FALSE;
218
219 s = bfd_make_section_with_flags (abfd, ".dynamic", flags);
220 if (s == NULL
221 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
222 return FALSE;
223
224 /* The special symbol _DYNAMIC is always set to the start of the
225 .dynamic section. We could set _DYNAMIC in a linker script, but we
226 only want to define it if we are, in fact, creating a .dynamic
227 section. We don't want to define it if there is no .dynamic
228 section, since on some ELF platforms the start up code examines it
229 to decide how to initialize the process. */
230 if (!_bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC"))
231 return FALSE;
232
233 if (info->emit_hash)
234 {
235 s = bfd_make_section_with_flags (abfd, ".hash", flags | SEC_READONLY);
236 if (s == NULL
237 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
238 return FALSE;
239 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
240 }
241
242 if (info->emit_gnu_hash)
243 {
244 s = bfd_make_section_with_flags (abfd, ".gnu.hash",
245 flags | SEC_READONLY);
246 if (s == NULL
247 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
248 return FALSE;
249 /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
250 4 32-bit words followed by variable count of 64-bit words, then
251 variable count of 32-bit words. */
252 if (bed->s->arch_size == 64)
253 elf_section_data (s)->this_hdr.sh_entsize = 0;
254 else
255 elf_section_data (s)->this_hdr.sh_entsize = 4;
256 }
257
258 /* Let the backend create the rest of the sections. This lets the
259 backend set the right flags. The backend will normally create
260 the .got and .plt sections. */
261 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
262 return FALSE;
263
264 elf_hash_table (info)->dynamic_sections_created = TRUE;
265
266 return TRUE;
267 }
268
269 /* Create dynamic sections when linking against a dynamic object. */
270
271 bfd_boolean
_bfd_elf_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)272 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
273 {
274 flagword flags, pltflags;
275 struct elf_link_hash_entry *h;
276 asection *s;
277 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
278
279 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
280 .rel[a].bss sections. */
281 flags = bed->dynamic_sec_flags;
282
283 pltflags = flags;
284 if (bed->plt_not_loaded)
285 /* We do not clear SEC_ALLOC here because we still want the OS to
286 allocate space for the section; it's just that there's nothing
287 to read in from the object file. */
288 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
289 else
290 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
291 if (bed->plt_readonly)
292 pltflags |= SEC_READONLY;
293
294 s = bfd_make_section_with_flags (abfd, ".plt", pltflags);
295 if (s == NULL
296 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
297 return FALSE;
298
299 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
300 .plt section. */
301 if (bed->want_plt_sym)
302 {
303 h = _bfd_elf_define_linkage_sym (abfd, info, s,
304 "_PROCEDURE_LINKAGE_TABLE_");
305 elf_hash_table (info)->hplt = h;
306 if (h == NULL)
307 return FALSE;
308 }
309
310 s = bfd_make_section_with_flags (abfd,
311 (bed->default_use_rela_p
312 ? ".rela.plt" : ".rel.plt"),
313 flags | SEC_READONLY);
314 if (s == NULL
315 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
316 return FALSE;
317
318 if (! _bfd_elf_create_got_section (abfd, info))
319 return FALSE;
320
321 if (bed->want_dynbss)
322 {
323 /* The .dynbss section is a place to put symbols which are defined
324 by dynamic objects, are referenced by regular objects, and are
325 not functions. We must allocate space for them in the process
326 image and use a R_*_COPY reloc to tell the dynamic linker to
327 initialize them at run time. The linker script puts the .dynbss
328 section into the .bss section of the final image. */
329 s = bfd_make_section_with_flags (abfd, ".dynbss",
330 (SEC_ALLOC
331 | SEC_LINKER_CREATED));
332 if (s == NULL)
333 return FALSE;
334
335 /* The .rel[a].bss section holds copy relocs. This section is not
336 normally needed. We need to create it here, though, so that the
337 linker will map it to an output section. We can't just create it
338 only if we need it, because we will not know whether we need it
339 until we have seen all the input files, and the first time the
340 main linker code calls BFD after examining all the input files
341 (size_dynamic_sections) the input sections have already been
342 mapped to the output sections. If the section turns out not to
343 be needed, we can discard it later. We will never need this
344 section when generating a shared object, since they do not use
345 copy relocs. */
346 if (! info->shared)
347 {
348 s = bfd_make_section_with_flags (abfd,
349 (bed->default_use_rela_p
350 ? ".rela.bss" : ".rel.bss"),
351 flags | SEC_READONLY);
352 if (s == NULL
353 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
354 return FALSE;
355 }
356 }
357
358 return TRUE;
359 }
360
361 /* Record a new dynamic symbol. We record the dynamic symbols as we
362 read the input files, since we need to have a list of all of them
363 before we can determine the final sizes of the output sections.
364 Note that we may actually call this function even though we are not
365 going to output any dynamic symbols; in some cases we know that a
366 symbol should be in the dynamic symbol table, but only if there is
367 one. */
368
369 bfd_boolean
bfd_elf_link_record_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)370 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
371 struct elf_link_hash_entry *h)
372 {
373 if (h->dynindx == -1)
374 {
375 struct elf_strtab_hash *dynstr;
376 char *p;
377 const char *name;
378 bfd_size_type indx;
379
380 /* XXX: The ABI draft says the linker must turn hidden and
381 internal symbols into STB_LOCAL symbols when producing the
382 DSO. However, if ld.so honors st_other in the dynamic table,
383 this would not be necessary. */
384 switch (ELF_ST_VISIBILITY (h->other))
385 {
386 case STV_INTERNAL:
387 case STV_HIDDEN:
388 if (h->root.type != bfd_link_hash_undefined
389 && h->root.type != bfd_link_hash_undefweak)
390 {
391 h->forced_local = 1;
392 if (!elf_hash_table (info)->is_relocatable_executable)
393 return TRUE;
394 }
395
396 default:
397 break;
398 }
399
400 h->dynindx = elf_hash_table (info)->dynsymcount;
401 ++elf_hash_table (info)->dynsymcount;
402
403 dynstr = elf_hash_table (info)->dynstr;
404 if (dynstr == NULL)
405 {
406 /* Create a strtab to hold the dynamic symbol names. */
407 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
408 if (dynstr == NULL)
409 return FALSE;
410 }
411
412 /* We don't put any version information in the dynamic string
413 table. */
414 name = h->root.root.string;
415 p = strchr (name, ELF_VER_CHR);
416 if (p != NULL)
417 /* We know that the p points into writable memory. In fact,
418 there are only a few symbols that have read-only names, being
419 those like _GLOBAL_OFFSET_TABLE_ that are created specially
420 by the backends. Most symbols will have names pointing into
421 an ELF string table read from a file, or to objalloc memory. */
422 *p = 0;
423
424 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
425
426 if (p != NULL)
427 *p = ELF_VER_CHR;
428
429 if (indx == (bfd_size_type) -1)
430 return FALSE;
431 h->dynstr_index = indx;
432 }
433
434 return TRUE;
435 }
436
437 /* Mark a symbol dynamic. */
438
439 void
bfd_elf_link_mark_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)440 bfd_elf_link_mark_dynamic_symbol (struct bfd_link_info *info,
441 struct elf_link_hash_entry *h,
442 Elf_Internal_Sym *sym)
443 {
444 struct bfd_elf_dynamic_list *d = info->dynamic_list;
445
446 /* It may be called more than once on the same H. */
447 if(h->dynamic || info->relocatable)
448 return;
449
450 if ((info->dynamic_data
451 && (h->type == STT_OBJECT
452 || (sym != NULL
453 && ELF_ST_TYPE (sym->st_info) == STT_OBJECT)))
454 || (d != NULL
455 && h->root.type == bfd_link_hash_new
456 && (*d->match) (&d->head, NULL, h->root.root.string)))
457 h->dynamic = 1;
458 }
459
460 /* Record an assignment to a symbol made by a linker script. We need
461 this in case some dynamic object refers to this symbol. */
462
463 bfd_boolean
bfd_elf_record_link_assignment(bfd * output_bfd,struct bfd_link_info * info,const char * name,bfd_boolean provide,bfd_boolean hidden)464 bfd_elf_record_link_assignment (bfd *output_bfd,
465 struct bfd_link_info *info,
466 const char *name,
467 bfd_boolean provide,
468 bfd_boolean hidden)
469 {
470 struct elf_link_hash_entry *h;
471 struct elf_link_hash_table *htab;
472
473 if (!is_elf_hash_table (info->hash))
474 return TRUE;
475
476 htab = elf_hash_table (info);
477 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
478 if (h == NULL)
479 return provide;
480
481 /* Since we're defining the symbol, don't let it seem to have not
482 been defined. record_dynamic_symbol and size_dynamic_sections
483 may depend on this. */
484 if (h->root.type == bfd_link_hash_undefweak
485 || h->root.type == bfd_link_hash_undefined)
486 {
487 h->root.type = bfd_link_hash_new;
488 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
489 bfd_link_repair_undef_list (&htab->root);
490 }
491 else if (h->root.type == bfd_link_hash_new)
492 {
493 bfd_elf_link_mark_dynamic_symbol (info, h, NULL);
494 h->non_elf = 0;
495 }
496 else if (h->root.type == bfd_link_hash_indirect)
497 {
498 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
499 struct elf_link_hash_entry *hv = h;
500 do
501 hv = (struct elf_link_hash_entry *) hv->root.u.i.link;
502 while (hv->root.type == bfd_link_hash_indirect
503 || hv->root.type == bfd_link_hash_warning);
504 h->root.type = bfd_link_hash_undefined;
505 hv->root.type = bfd_link_hash_indirect;
506 hv->root.u.i.link = (struct bfd_link_hash_entry *) h;
507 (*bed->elf_backend_copy_indirect_symbol) (info, h, hv);
508 }
509 else if (h->root.type == bfd_link_hash_warning)
510 {
511 abort ();
512 }
513
514 /* If this symbol is being provided by the linker script, and it is
515 currently defined by a dynamic object, but not by a regular
516 object, then mark it as undefined so that the generic linker will
517 force the correct value. */
518 if (provide
519 && h->def_dynamic
520 && !h->def_regular)
521 h->root.type = bfd_link_hash_undefined;
522
523 /* If this symbol is not being provided by the linker script, and it is
524 currently defined by a dynamic object, but not by a regular object,
525 then clear out any version information because the symbol will not be
526 associated with the dynamic object any more. */
527 if (!provide
528 && h->def_dynamic
529 && !h->def_regular)
530 h->verinfo.verdef = NULL;
531
532 h->def_regular = 1;
533
534 if (provide && hidden)
535 {
536 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
537
538 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
539 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
540 }
541
542 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
543 and executables. */
544 if (!info->relocatable
545 && h->dynindx != -1
546 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
547 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
548 h->forced_local = 1;
549
550 if ((h->def_dynamic
551 || h->ref_dynamic
552 || info->shared
553 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
554 && h->dynindx == -1)
555 {
556 if (! bfd_elf_link_record_dynamic_symbol (info, h))
557 return FALSE;
558
559 /* If this is a weak defined symbol, and we know a corresponding
560 real symbol from the same dynamic object, make sure the real
561 symbol is also made into a dynamic symbol. */
562 if (h->u.weakdef != NULL
563 && h->u.weakdef->dynindx == -1)
564 {
565 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
566 return FALSE;
567 }
568 }
569
570 return TRUE;
571 }
572
573 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
574 success, and 2 on a failure caused by attempting to record a symbol
575 in a discarded section, eg. a discarded link-once section symbol. */
576
577 int
bfd_elf_link_record_local_dynamic_symbol(struct bfd_link_info * info,bfd * input_bfd,long input_indx)578 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
579 bfd *input_bfd,
580 long input_indx)
581 {
582 bfd_size_type amt;
583 struct elf_link_local_dynamic_entry *entry;
584 struct elf_link_hash_table *eht;
585 struct elf_strtab_hash *dynstr;
586 unsigned long dynstr_index;
587 char *name;
588 Elf_External_Sym_Shndx eshndx;
589 char esym[sizeof (Elf64_External_Sym)];
590
591 if (! is_elf_hash_table (info->hash))
592 return 0;
593
594 /* See if the entry exists already. */
595 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
596 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
597 return 1;
598
599 amt = sizeof (*entry);
600 entry = bfd_alloc (input_bfd, amt);
601 if (entry == NULL)
602 return 0;
603
604 /* Go find the symbol, so that we can find it's name. */
605 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
606 1, input_indx, &entry->isym, esym, &eshndx))
607 {
608 bfd_release (input_bfd, entry);
609 return 0;
610 }
611
612 if (entry->isym.st_shndx != SHN_UNDEF
613 && (entry->isym.st_shndx < SHN_LORESERVE
614 || entry->isym.st_shndx > SHN_HIRESERVE))
615 {
616 asection *s;
617
618 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
619 if (s == NULL || bfd_is_abs_section (s->output_section))
620 {
621 /* We can still bfd_release here as nothing has done another
622 bfd_alloc. We can't do this later in this function. */
623 bfd_release (input_bfd, entry);
624 return 2;
625 }
626 }
627
628 name = (bfd_elf_string_from_elf_section
629 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
630 entry->isym.st_name));
631
632 dynstr = elf_hash_table (info)->dynstr;
633 if (dynstr == NULL)
634 {
635 /* Create a strtab to hold the dynamic symbol names. */
636 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
637 if (dynstr == NULL)
638 return 0;
639 }
640
641 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
642 if (dynstr_index == (unsigned long) -1)
643 return 0;
644 entry->isym.st_name = dynstr_index;
645
646 eht = elf_hash_table (info);
647
648 entry->next = eht->dynlocal;
649 eht->dynlocal = entry;
650 entry->input_bfd = input_bfd;
651 entry->input_indx = input_indx;
652 eht->dynsymcount++;
653
654 /* Whatever binding the symbol had before, it's now local. */
655 entry->isym.st_info
656 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
657
658 /* The dynindx will be set at the end of size_dynamic_sections. */
659
660 return 1;
661 }
662
663 /* Return the dynindex of a local dynamic symbol. */
664
665 long
_bfd_elf_link_lookup_local_dynindx(struct bfd_link_info * info,bfd * input_bfd,long input_indx)666 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
667 bfd *input_bfd,
668 long input_indx)
669 {
670 struct elf_link_local_dynamic_entry *e;
671
672 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
673 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
674 return e->dynindx;
675 return -1;
676 }
677
678 /* This function is used to renumber the dynamic symbols, if some of
679 them are removed because they are marked as local. This is called
680 via elf_link_hash_traverse. */
681
682 static bfd_boolean
elf_link_renumber_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)683 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
684 void *data)
685 {
686 size_t *count = data;
687
688 if (h->root.type == bfd_link_hash_warning)
689 h = (struct elf_link_hash_entry *) h->root.u.i.link;
690
691 if (h->forced_local)
692 return TRUE;
693
694 if (h->dynindx != -1)
695 h->dynindx = ++(*count);
696
697 return TRUE;
698 }
699
700
701 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
702 STB_LOCAL binding. */
703
704 static bfd_boolean
elf_link_renumber_local_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)705 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
706 void *data)
707 {
708 size_t *count = data;
709
710 if (h->root.type == bfd_link_hash_warning)
711 h = (struct elf_link_hash_entry *) h->root.u.i.link;
712
713 if (!h->forced_local)
714 return TRUE;
715
716 if (h->dynindx != -1)
717 h->dynindx = ++(*count);
718
719 return TRUE;
720 }
721
722 /* Return true if the dynamic symbol for a given section should be
723 omitted when creating a shared library. */
724 bfd_boolean
_bfd_elf_link_omit_section_dynsym(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,asection * p)725 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
726 struct bfd_link_info *info,
727 asection *p)
728 {
729 struct elf_link_hash_table *htab;
730
731 switch (elf_section_data (p)->this_hdr.sh_type)
732 {
733 case SHT_PROGBITS:
734 case SHT_NOBITS:
735 /* If sh_type is yet undecided, assume it could be
736 SHT_PROGBITS/SHT_NOBITS. */
737 case SHT_NULL:
738 htab = elf_hash_table (info);
739 if (p == htab->tls_sec)
740 return FALSE;
741
742 if (htab->text_index_section != NULL)
743 return p != htab->text_index_section && p != htab->data_index_section;
744
745 if (strcmp (p->name, ".got") == 0
746 || strcmp (p->name, ".got.plt") == 0
747 || strcmp (p->name, ".plt") == 0)
748 {
749 asection *ip;
750
751 if (htab->dynobj != NULL
752 && (ip = bfd_get_section_by_name (htab->dynobj, p->name)) != NULL
753 && (ip->flags & SEC_LINKER_CREATED)
754 && ip->output_section == p)
755 return TRUE;
756 }
757 return FALSE;
758
759 /* There shouldn't be section relative relocations
760 against any other section. */
761 default:
762 return TRUE;
763 }
764 }
765
766 /* Assign dynsym indices. In a shared library we generate a section
767 symbol for each output section, which come first. Next come symbols
768 which have been forced to local binding. Then all of the back-end
769 allocated local dynamic syms, followed by the rest of the global
770 symbols. */
771
772 static unsigned long
_bfd_elf_link_renumber_dynsyms(bfd * output_bfd,struct bfd_link_info * info,unsigned long * section_sym_count)773 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
774 struct bfd_link_info *info,
775 unsigned long *section_sym_count)
776 {
777 unsigned long dynsymcount = 0;
778
779 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
780 {
781 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
782 asection *p;
783 for (p = output_bfd->sections; p ; p = p->next)
784 if ((p->flags & SEC_EXCLUDE) == 0
785 && (p->flags & SEC_ALLOC) != 0
786 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
787 elf_section_data (p)->dynindx = ++dynsymcount;
788 else
789 elf_section_data (p)->dynindx = 0;
790 }
791 *section_sym_count = dynsymcount;
792
793 elf_link_hash_traverse (elf_hash_table (info),
794 elf_link_renumber_local_hash_table_dynsyms,
795 &dynsymcount);
796
797 if (elf_hash_table (info)->dynlocal)
798 {
799 struct elf_link_local_dynamic_entry *p;
800 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
801 p->dynindx = ++dynsymcount;
802 }
803
804 elf_link_hash_traverse (elf_hash_table (info),
805 elf_link_renumber_hash_table_dynsyms,
806 &dynsymcount);
807
808 /* There is an unused NULL entry at the head of the table which
809 we must account for in our count. Unless there weren't any
810 symbols, which means we'll have no table at all. */
811 if (dynsymcount != 0)
812 ++dynsymcount;
813
814 elf_hash_table (info)->dynsymcount = dynsymcount;
815 return dynsymcount;
816 }
817
818 /* This function is called when we want to define a new symbol. It
819 handles the various cases which arise when we find a definition in
820 a dynamic object, or when there is already a definition in a
821 dynamic object. The new symbol is described by NAME, SYM, PSEC,
822 and PVALUE. We set SYM_HASH to the hash table entry. We set
823 OVERRIDE if the old symbol is overriding a new definition. We set
824 TYPE_CHANGE_OK if it is OK for the type to change. We set
825 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
826 change, we mean that we shouldn't warn if the type or size does
827 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
828 object is overridden by a regular object. */
829
830 bfd_boolean
_bfd_elf_merge_symbol(bfd * abfd,struct bfd_link_info * info,const char * name,Elf_Internal_Sym * sym,asection ** psec,bfd_vma * pvalue,unsigned int * pold_alignment,struct elf_link_hash_entry ** sym_hash,bfd_boolean * skip,bfd_boolean * override,bfd_boolean * type_change_ok,bfd_boolean * size_change_ok)831 _bfd_elf_merge_symbol (bfd *abfd,
832 struct bfd_link_info *info,
833 const char *name,
834 Elf_Internal_Sym *sym,
835 asection **psec,
836 bfd_vma *pvalue,
837 unsigned int *pold_alignment,
838 struct elf_link_hash_entry **sym_hash,
839 bfd_boolean *skip,
840 bfd_boolean *override,
841 bfd_boolean *type_change_ok,
842 bfd_boolean *size_change_ok)
843 {
844 asection *sec, *oldsec;
845 struct elf_link_hash_entry *h;
846 struct elf_link_hash_entry *flip;
847 int bind;
848 bfd *oldbfd;
849 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
850 bfd_boolean newweak, oldweak;
851 const struct elf_backend_data *bed;
852
853 *skip = FALSE;
854 *override = FALSE;
855
856 sec = *psec;
857 bind = ELF_ST_BIND (sym->st_info);
858
859 /* Silently discard TLS symbols from --just-syms. There's no way to
860 combine a static TLS block with a new TLS block for this executable. */
861 if (ELF_ST_TYPE (sym->st_info) == STT_TLS
862 && sec->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
863 {
864 *skip = TRUE;
865 return TRUE;
866 }
867
868 if (! bfd_is_und_section (sec))
869 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
870 else
871 h = ((struct elf_link_hash_entry *)
872 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
873 if (h == NULL)
874 return FALSE;
875 *sym_hash = h;
876
877 bed = get_elf_backend_data (abfd);
878
879 /* This code is for coping with dynamic objects, and is only useful
880 if we are doing an ELF link. */
881 if (!(*bed->relocs_compatible) (abfd->xvec, info->hash->creator))
882 return TRUE;
883
884 /* For merging, we only care about real symbols. */
885
886 while (h->root.type == bfd_link_hash_indirect
887 || h->root.type == bfd_link_hash_warning)
888 h = (struct elf_link_hash_entry *) h->root.u.i.link;
889
890 /* We have to check it for every instance since the first few may be
891 refereences and not all compilers emit symbol type for undefined
892 symbols. */
893 bfd_elf_link_mark_dynamic_symbol (info, h, sym);
894
895 /* If we just created the symbol, mark it as being an ELF symbol.
896 Other than that, there is nothing to do--there is no merge issue
897 with a newly defined symbol--so we just return. */
898
899 if (h->root.type == bfd_link_hash_new)
900 {
901 h->non_elf = 0;
902 return TRUE;
903 }
904
905 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
906 existing symbol. */
907
908 switch (h->root.type)
909 {
910 default:
911 oldbfd = NULL;
912 oldsec = NULL;
913 break;
914
915 case bfd_link_hash_undefined:
916 case bfd_link_hash_undefweak:
917 oldbfd = h->root.u.undef.abfd;
918 oldsec = NULL;
919 break;
920
921 case bfd_link_hash_defined:
922 case bfd_link_hash_defweak:
923 oldbfd = h->root.u.def.section->owner;
924 oldsec = h->root.u.def.section;
925 break;
926
927 case bfd_link_hash_common:
928 oldbfd = h->root.u.c.p->section->owner;
929 oldsec = h->root.u.c.p->section;
930 break;
931 }
932
933 /* In cases involving weak versioned symbols, we may wind up trying
934 to merge a symbol with itself. Catch that here, to avoid the
935 confusion that results if we try to override a symbol with
936 itself. The additional tests catch cases like
937 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
938 dynamic object, which we do want to handle here. */
939 if (abfd == oldbfd
940 && ((abfd->flags & DYNAMIC) == 0
941 || !h->def_regular))
942 return TRUE;
943
944 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
945 respectively, is from a dynamic object. */
946
947 newdyn = (abfd->flags & DYNAMIC) != 0;
948
949 olddyn = FALSE;
950 if (oldbfd != NULL)
951 olddyn = (oldbfd->flags & DYNAMIC) != 0;
952 else if (oldsec != NULL)
953 {
954 /* This handles the special SHN_MIPS_{TEXT,DATA} section
955 indices used by MIPS ELF. */
956 olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
957 }
958
959 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
960 respectively, appear to be a definition rather than reference. */
961
962 newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
963
964 olddef = (h->root.type != bfd_link_hash_undefined
965 && h->root.type != bfd_link_hash_undefweak
966 && h->root.type != bfd_link_hash_common);
967
968 /* When we try to create a default indirect symbol from the dynamic
969 definition with the default version, we skip it if its type and
970 the type of existing regular definition mismatch. We only do it
971 if the existing regular definition won't be dynamic. */
972 if (pold_alignment == NULL
973 && !info->shared
974 && !info->export_dynamic
975 && !h->ref_dynamic
976 && newdyn
977 && newdef
978 && !olddyn
979 && (olddef || h->root.type == bfd_link_hash_common)
980 && ELF_ST_TYPE (sym->st_info) != h->type
981 && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
982 && h->type != STT_NOTYPE
983 && !(bed->is_function_type (ELF_ST_TYPE (sym->st_info))
984 && bed->is_function_type (h->type)))
985 {
986 *skip = TRUE;
987 return TRUE;
988 }
989
990 /* Check TLS symbol. We don't check undefined symbol introduced by
991 "ld -u". */
992 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
993 && ELF_ST_TYPE (sym->st_info) != h->type
994 && oldbfd != NULL)
995 {
996 bfd *ntbfd, *tbfd;
997 bfd_boolean ntdef, tdef;
998 asection *ntsec, *tsec;
999
1000 if (h->type == STT_TLS)
1001 {
1002 ntbfd = abfd;
1003 ntsec = sec;
1004 ntdef = newdef;
1005 tbfd = oldbfd;
1006 tsec = oldsec;
1007 tdef = olddef;
1008 }
1009 else
1010 {
1011 ntbfd = oldbfd;
1012 ntsec = oldsec;
1013 ntdef = olddef;
1014 tbfd = abfd;
1015 tsec = sec;
1016 tdef = newdef;
1017 }
1018
1019 if (tdef && ntdef)
1020 (*_bfd_error_handler)
1021 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
1022 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
1023 else if (!tdef && !ntdef)
1024 (*_bfd_error_handler)
1025 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
1026 tbfd, ntbfd, h->root.root.string);
1027 else if (tdef)
1028 (*_bfd_error_handler)
1029 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
1030 tbfd, tsec, ntbfd, h->root.root.string);
1031 else
1032 (*_bfd_error_handler)
1033 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
1034 tbfd, ntbfd, ntsec, h->root.root.string);
1035
1036 bfd_set_error (bfd_error_bad_value);
1037 return FALSE;
1038 }
1039
1040 /* We need to remember if a symbol has a definition in a dynamic
1041 object or is weak in all dynamic objects. Internal and hidden
1042 visibility will make it unavailable to dynamic objects. */
1043 if (newdyn && !h->dynamic_def)
1044 {
1045 if (!bfd_is_und_section (sec))
1046 h->dynamic_def = 1;
1047 else
1048 {
1049 /* Check if this symbol is weak in all dynamic objects. If it
1050 is the first time we see it in a dynamic object, we mark
1051 if it is weak. Otherwise, we clear it. */
1052 if (!h->ref_dynamic)
1053 {
1054 if (bind == STB_WEAK)
1055 h->dynamic_weak = 1;
1056 }
1057 else if (bind != STB_WEAK)
1058 h->dynamic_weak = 0;
1059 }
1060 }
1061
1062 /* If the old symbol has non-default visibility, we ignore the new
1063 definition from a dynamic object. */
1064 if (newdyn
1065 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1066 && !bfd_is_und_section (sec))
1067 {
1068 *skip = TRUE;
1069 /* Make sure this symbol is dynamic. */
1070 h->ref_dynamic = 1;
1071 /* A protected symbol has external availability. Make sure it is
1072 recorded as dynamic.
1073
1074 FIXME: Should we check type and size for protected symbol? */
1075 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1076 return bfd_elf_link_record_dynamic_symbol (info, h);
1077 else
1078 return TRUE;
1079 }
1080 else if (!newdyn
1081 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1082 && h->def_dynamic)
1083 {
1084 /* If the new symbol with non-default visibility comes from a
1085 relocatable file and the old definition comes from a dynamic
1086 object, we remove the old definition. */
1087 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1088 {
1089 /* Handle the case where the old dynamic definition is
1090 default versioned. We need to copy the symbol info from
1091 the symbol with default version to the normal one if it
1092 was referenced before. */
1093 if (h->ref_regular)
1094 {
1095 const struct elf_backend_data *bed
1096 = get_elf_backend_data (abfd);
1097 struct elf_link_hash_entry *vh = *sym_hash;
1098 vh->root.type = h->root.type;
1099 h->root.type = bfd_link_hash_indirect;
1100 (*bed->elf_backend_copy_indirect_symbol) (info, vh, h);
1101 /* Protected symbols will override the dynamic definition
1102 with default version. */
1103 if (ELF_ST_VISIBILITY (sym->st_other) == STV_PROTECTED)
1104 {
1105 h->root.u.i.link = (struct bfd_link_hash_entry *) vh;
1106 vh->dynamic_def = 1;
1107 vh->ref_dynamic = 1;
1108 }
1109 else
1110 {
1111 h->root.type = vh->root.type;
1112 vh->ref_dynamic = 0;
1113 /* We have to hide it here since it was made dynamic
1114 global with extra bits when the symbol info was
1115 copied from the old dynamic definition. */
1116 (*bed->elf_backend_hide_symbol) (info, vh, TRUE);
1117 }
1118 h = vh;
1119 }
1120 else
1121 h = *sym_hash;
1122 }
1123
1124 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1125 && bfd_is_und_section (sec))
1126 {
1127 /* If the new symbol is undefined and the old symbol was
1128 also undefined before, we need to make sure
1129 _bfd_generic_link_add_one_symbol doesn't mess
1130 up the linker hash table undefs list. Since the old
1131 definition came from a dynamic object, it is still on the
1132 undefs list. */
1133 h->root.type = bfd_link_hash_undefined;
1134 h->root.u.undef.abfd = abfd;
1135 }
1136 else
1137 {
1138 h->root.type = bfd_link_hash_new;
1139 h->root.u.undef.abfd = NULL;
1140 }
1141
1142 if (h->def_dynamic)
1143 {
1144 h->def_dynamic = 0;
1145 h->ref_dynamic = 1;
1146 h->dynamic_def = 1;
1147 }
1148 /* FIXME: Should we check type and size for protected symbol? */
1149 h->size = 0;
1150 h->type = 0;
1151 return TRUE;
1152 }
1153
1154 /* Differentiate strong and weak symbols. */
1155 newweak = bind == STB_WEAK;
1156 oldweak = (h->root.type == bfd_link_hash_defweak
1157 || h->root.type == bfd_link_hash_undefweak);
1158
1159 /* If a new weak symbol definition comes from a regular file and the
1160 old symbol comes from a dynamic library, we treat the new one as
1161 strong. Similarly, an old weak symbol definition from a regular
1162 file is treated as strong when the new symbol comes from a dynamic
1163 library. Further, an old weak symbol from a dynamic library is
1164 treated as strong if the new symbol is from a dynamic library.
1165 This reflects the way glibc's ld.so works.
1166
1167 Do this before setting *type_change_ok or *size_change_ok so that
1168 we warn properly when dynamic library symbols are overridden. */
1169
1170 if (newdef && !newdyn && olddyn)
1171 newweak = FALSE;
1172 if (olddef && newdyn)
1173 oldweak = FALSE;
1174
1175 /* Allow changes between different types of funciton symbol. */
1176 if (bed->is_function_type (ELF_ST_TYPE (sym->st_info))
1177 && bed->is_function_type (h->type))
1178 *type_change_ok = TRUE;
1179
1180 /* It's OK to change the type if either the existing symbol or the
1181 new symbol is weak. A type change is also OK if the old symbol
1182 is undefined and the new symbol is defined. */
1183
1184 if (oldweak
1185 || newweak
1186 || (newdef
1187 && h->root.type == bfd_link_hash_undefined))
1188 *type_change_ok = TRUE;
1189
1190 /* It's OK to change the size if either the existing symbol or the
1191 new symbol is weak, or if the old symbol is undefined. */
1192
1193 if (*type_change_ok
1194 || h->root.type == bfd_link_hash_undefined)
1195 *size_change_ok = TRUE;
1196
1197 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1198 symbol, respectively, appears to be a common symbol in a dynamic
1199 object. If a symbol appears in an uninitialized section, and is
1200 not weak, and is not a function, then it may be a common symbol
1201 which was resolved when the dynamic object was created. We want
1202 to treat such symbols specially, because they raise special
1203 considerations when setting the symbol size: if the symbol
1204 appears as a common symbol in a regular object, and the size in
1205 the regular object is larger, we must make sure that we use the
1206 larger size. This problematic case can always be avoided in C,
1207 but it must be handled correctly when using Fortran shared
1208 libraries.
1209
1210 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1211 likewise for OLDDYNCOMMON and OLDDEF.
1212
1213 Note that this test is just a heuristic, and that it is quite
1214 possible to have an uninitialized symbol in a shared object which
1215 is really a definition, rather than a common symbol. This could
1216 lead to some minor confusion when the symbol really is a common
1217 symbol in some regular object. However, I think it will be
1218 harmless. */
1219
1220 if (newdyn
1221 && newdef
1222 && !newweak
1223 && (sec->flags & SEC_ALLOC) != 0
1224 && (sec->flags & SEC_LOAD) == 0
1225 && sym->st_size > 0
1226 && !bed->is_function_type (ELF_ST_TYPE (sym->st_info)))
1227 newdyncommon = TRUE;
1228 else
1229 newdyncommon = FALSE;
1230
1231 if (olddyn
1232 && olddef
1233 && h->root.type == bfd_link_hash_defined
1234 && h->def_dynamic
1235 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1236 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1237 && h->size > 0
1238 && !bed->is_function_type (h->type))
1239 olddyncommon = TRUE;
1240 else
1241 olddyncommon = FALSE;
1242
1243 /* We now know everything about the old and new symbols. We ask the
1244 backend to check if we can merge them. */
1245 if (bed->merge_symbol
1246 && !bed->merge_symbol (info, sym_hash, h, sym, psec, pvalue,
1247 pold_alignment, skip, override,
1248 type_change_ok, size_change_ok,
1249 &newdyn, &newdef, &newdyncommon, &newweak,
1250 abfd, &sec,
1251 &olddyn, &olddef, &olddyncommon, &oldweak,
1252 oldbfd, &oldsec))
1253 return FALSE;
1254
1255 /* If both the old and the new symbols look like common symbols in a
1256 dynamic object, set the size of the symbol to the larger of the
1257 two. */
1258
1259 if (olddyncommon
1260 && newdyncommon
1261 && sym->st_size != h->size)
1262 {
1263 /* Since we think we have two common symbols, issue a multiple
1264 common warning if desired. Note that we only warn if the
1265 size is different. If the size is the same, we simply let
1266 the old symbol override the new one as normally happens with
1267 symbols defined in dynamic objects. */
1268
1269 if (! ((*info->callbacks->multiple_common)
1270 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1271 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1272 return FALSE;
1273
1274 if (sym->st_size > h->size)
1275 h->size = sym->st_size;
1276
1277 *size_change_ok = TRUE;
1278 }
1279
1280 /* If we are looking at a dynamic object, and we have found a
1281 definition, we need to see if the symbol was already defined by
1282 some other object. If so, we want to use the existing
1283 definition, and we do not want to report a multiple symbol
1284 definition error; we do this by clobbering *PSEC to be
1285 bfd_und_section_ptr.
1286
1287 We treat a common symbol as a definition if the symbol in the
1288 shared library is a function, since common symbols always
1289 represent variables; this can cause confusion in principle, but
1290 any such confusion would seem to indicate an erroneous program or
1291 shared library. We also permit a common symbol in a regular
1292 object to override a weak symbol in a shared object. */
1293
1294 if (newdyn
1295 && newdef
1296 && (olddef
1297 || (h->root.type == bfd_link_hash_common
1298 && (newweak
1299 || bed->is_function_type (ELF_ST_TYPE (sym->st_info))))))
1300 {
1301 *override = TRUE;
1302 newdef = FALSE;
1303 newdyncommon = FALSE;
1304
1305 *psec = sec = bfd_und_section_ptr;
1306 *size_change_ok = TRUE;
1307
1308 /* If we get here when the old symbol is a common symbol, then
1309 we are explicitly letting it override a weak symbol or
1310 function in a dynamic object, and we don't want to warn about
1311 a type change. If the old symbol is a defined symbol, a type
1312 change warning may still be appropriate. */
1313
1314 if (h->root.type == bfd_link_hash_common)
1315 *type_change_ok = TRUE;
1316 }
1317
1318 /* Handle the special case of an old common symbol merging with a
1319 new symbol which looks like a common symbol in a shared object.
1320 We change *PSEC and *PVALUE to make the new symbol look like a
1321 common symbol, and let _bfd_generic_link_add_one_symbol do the
1322 right thing. */
1323
1324 if (newdyncommon
1325 && h->root.type == bfd_link_hash_common)
1326 {
1327 *override = TRUE;
1328 newdef = FALSE;
1329 newdyncommon = FALSE;
1330 *pvalue = sym->st_size;
1331 *psec = sec = bed->common_section (oldsec);
1332 *size_change_ok = TRUE;
1333 }
1334
1335 /* Skip weak definitions of symbols that are already defined. */
1336 if (newdef && olddef && newweak)
1337 *skip = TRUE;
1338
1339 /* If the old symbol is from a dynamic object, and the new symbol is
1340 a definition which is not from a dynamic object, then the new
1341 symbol overrides the old symbol. Symbols from regular files
1342 always take precedence over symbols from dynamic objects, even if
1343 they are defined after the dynamic object in the link.
1344
1345 As above, we again permit a common symbol in a regular object to
1346 override a definition in a shared object if the shared object
1347 symbol is a function or is weak. */
1348
1349 flip = NULL;
1350 if (!newdyn
1351 && (newdef
1352 || (bfd_is_com_section (sec)
1353 && (oldweak
1354 || bed->is_function_type (h->type))))
1355 && olddyn
1356 && olddef
1357 && h->def_dynamic)
1358 {
1359 /* Change the hash table entry to undefined, and let
1360 _bfd_generic_link_add_one_symbol do the right thing with the
1361 new definition. */
1362
1363 h->root.type = bfd_link_hash_undefined;
1364 h->root.u.undef.abfd = h->root.u.def.section->owner;
1365 *size_change_ok = TRUE;
1366
1367 olddef = FALSE;
1368 olddyncommon = FALSE;
1369
1370 /* We again permit a type change when a common symbol may be
1371 overriding a function. */
1372
1373 if (bfd_is_com_section (sec))
1374 *type_change_ok = TRUE;
1375
1376 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1377 flip = *sym_hash;
1378 else
1379 /* This union may have been set to be non-NULL when this symbol
1380 was seen in a dynamic object. We must force the union to be
1381 NULL, so that it is correct for a regular symbol. */
1382 h->verinfo.vertree = NULL;
1383 }
1384
1385 /* Handle the special case of a new common symbol merging with an
1386 old symbol that looks like it might be a common symbol defined in
1387 a shared object. Note that we have already handled the case in
1388 which a new common symbol should simply override the definition
1389 in the shared library. */
1390
1391 if (! newdyn
1392 && bfd_is_com_section (sec)
1393 && olddyncommon)
1394 {
1395 /* It would be best if we could set the hash table entry to a
1396 common symbol, but we don't know what to use for the section
1397 or the alignment. */
1398 if (! ((*info->callbacks->multiple_common)
1399 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1400 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1401 return FALSE;
1402
1403 /* If the presumed common symbol in the dynamic object is
1404 larger, pretend that the new symbol has its size. */
1405
1406 if (h->size > *pvalue)
1407 *pvalue = h->size;
1408
1409 /* We need to remember the alignment required by the symbol
1410 in the dynamic object. */
1411 BFD_ASSERT (pold_alignment);
1412 *pold_alignment = h->root.u.def.section->alignment_power;
1413
1414 olddef = FALSE;
1415 olddyncommon = FALSE;
1416
1417 h->root.type = bfd_link_hash_undefined;
1418 h->root.u.undef.abfd = h->root.u.def.section->owner;
1419
1420 *size_change_ok = TRUE;
1421 *type_change_ok = TRUE;
1422
1423 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1424 flip = *sym_hash;
1425 else
1426 h->verinfo.vertree = NULL;
1427 }
1428
1429 if (flip != NULL)
1430 {
1431 /* Handle the case where we had a versioned symbol in a dynamic
1432 library and now find a definition in a normal object. In this
1433 case, we make the versioned symbol point to the normal one. */
1434 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1435 flip->root.type = h->root.type;
1436 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1437 h->root.type = bfd_link_hash_indirect;
1438 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1439 (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1440 if (h->def_dynamic)
1441 {
1442 h->def_dynamic = 0;
1443 flip->ref_dynamic = 1;
1444 }
1445 }
1446
1447 return TRUE;
1448 }
1449
1450 /* This function is called to create an indirect symbol from the
1451 default for the symbol with the default version if needed. The
1452 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1453 set DYNSYM if the new indirect symbol is dynamic. */
1454
1455 bfd_boolean
_bfd_elf_add_default_symbol(bfd * abfd,struct bfd_link_info * info,struct elf_link_hash_entry * h,const char * name,Elf_Internal_Sym * sym,asection ** psec,bfd_vma * value,bfd_boolean * dynsym,bfd_boolean override)1456 _bfd_elf_add_default_symbol (bfd *abfd,
1457 struct bfd_link_info *info,
1458 struct elf_link_hash_entry *h,
1459 const char *name,
1460 Elf_Internal_Sym *sym,
1461 asection **psec,
1462 bfd_vma *value,
1463 bfd_boolean *dynsym,
1464 bfd_boolean override)
1465 {
1466 bfd_boolean type_change_ok;
1467 bfd_boolean size_change_ok;
1468 bfd_boolean skip;
1469 char *shortname;
1470 struct elf_link_hash_entry *hi;
1471 struct bfd_link_hash_entry *bh;
1472 const struct elf_backend_data *bed;
1473 bfd_boolean collect;
1474 bfd_boolean dynamic;
1475 char *p;
1476 size_t len, shortlen;
1477 asection *sec;
1478
1479 /* If this symbol has a version, and it is the default version, we
1480 create an indirect symbol from the default name to the fully
1481 decorated name. This will cause external references which do not
1482 specify a version to be bound to this version of the symbol. */
1483 p = strchr (name, ELF_VER_CHR);
1484 if (p == NULL || p[1] != ELF_VER_CHR)
1485 return TRUE;
1486
1487 if (override)
1488 {
1489 /* We are overridden by an old definition. We need to check if we
1490 need to create the indirect symbol from the default name. */
1491 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1492 FALSE, FALSE);
1493 BFD_ASSERT (hi != NULL);
1494 if (hi == h)
1495 return TRUE;
1496 while (hi->root.type == bfd_link_hash_indirect
1497 || hi->root.type == bfd_link_hash_warning)
1498 {
1499 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1500 if (hi == h)
1501 return TRUE;
1502 }
1503 }
1504
1505 bed = get_elf_backend_data (abfd);
1506 collect = bed->collect;
1507 dynamic = (abfd->flags & DYNAMIC) != 0;
1508
1509 shortlen = p - name;
1510 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1511 if (shortname == NULL)
1512 return FALSE;
1513 memcpy (shortname, name, shortlen);
1514 shortname[shortlen] = '\0';
1515
1516 /* We are going to create a new symbol. Merge it with any existing
1517 symbol with this name. For the purposes of the merge, act as
1518 though we were defining the symbol we just defined, although we
1519 actually going to define an indirect symbol. */
1520 type_change_ok = FALSE;
1521 size_change_ok = FALSE;
1522 sec = *psec;
1523 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1524 NULL, &hi, &skip, &override,
1525 &type_change_ok, &size_change_ok))
1526 return FALSE;
1527
1528 if (skip)
1529 goto nondefault;
1530
1531 if (! override)
1532 {
1533 bh = &hi->root;
1534 if (! (_bfd_generic_link_add_one_symbol
1535 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1536 0, name, FALSE, collect, &bh)))
1537 return FALSE;
1538 hi = (struct elf_link_hash_entry *) bh;
1539 }
1540 else
1541 {
1542 /* In this case the symbol named SHORTNAME is overriding the
1543 indirect symbol we want to add. We were planning on making
1544 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1545 is the name without a version. NAME is the fully versioned
1546 name, and it is the default version.
1547
1548 Overriding means that we already saw a definition for the
1549 symbol SHORTNAME in a regular object, and it is overriding
1550 the symbol defined in the dynamic object.
1551
1552 When this happens, we actually want to change NAME, the
1553 symbol we just added, to refer to SHORTNAME. This will cause
1554 references to NAME in the shared object to become references
1555 to SHORTNAME in the regular object. This is what we expect
1556 when we override a function in a shared object: that the
1557 references in the shared object will be mapped to the
1558 definition in the regular object. */
1559
1560 while (hi->root.type == bfd_link_hash_indirect
1561 || hi->root.type == bfd_link_hash_warning)
1562 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1563
1564 h->root.type = bfd_link_hash_indirect;
1565 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1566 if (h->def_dynamic)
1567 {
1568 h->def_dynamic = 0;
1569 hi->ref_dynamic = 1;
1570 if (hi->ref_regular
1571 || hi->def_regular)
1572 {
1573 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1574 return FALSE;
1575 }
1576 }
1577
1578 /* Now set HI to H, so that the following code will set the
1579 other fields correctly. */
1580 hi = h;
1581 }
1582
1583 /* Check if HI is a warning symbol. */
1584 if (hi->root.type == bfd_link_hash_warning)
1585 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1586
1587 /* If there is a duplicate definition somewhere, then HI may not
1588 point to an indirect symbol. We will have reported an error to
1589 the user in that case. */
1590
1591 if (hi->root.type == bfd_link_hash_indirect)
1592 {
1593 struct elf_link_hash_entry *ht;
1594
1595 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1596 (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
1597
1598 /* See if the new flags lead us to realize that the symbol must
1599 be dynamic. */
1600 if (! *dynsym)
1601 {
1602 if (! dynamic)
1603 {
1604 if (info->shared
1605 || hi->ref_dynamic)
1606 *dynsym = TRUE;
1607 }
1608 else
1609 {
1610 if (hi->ref_regular)
1611 *dynsym = TRUE;
1612 }
1613 }
1614 }
1615
1616 /* We also need to define an indirection from the nondefault version
1617 of the symbol. */
1618
1619 nondefault:
1620 len = strlen (name);
1621 shortname = bfd_hash_allocate (&info->hash->table, len);
1622 if (shortname == NULL)
1623 return FALSE;
1624 memcpy (shortname, name, shortlen);
1625 memcpy (shortname + shortlen, p + 1, len - shortlen);
1626
1627 /* Once again, merge with any existing symbol. */
1628 type_change_ok = FALSE;
1629 size_change_ok = FALSE;
1630 sec = *psec;
1631 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1632 NULL, &hi, &skip, &override,
1633 &type_change_ok, &size_change_ok))
1634 return FALSE;
1635
1636 if (skip)
1637 return TRUE;
1638
1639 if (override)
1640 {
1641 /* Here SHORTNAME is a versioned name, so we don't expect to see
1642 the type of override we do in the case above unless it is
1643 overridden by a versioned definition. */
1644 if (hi->root.type != bfd_link_hash_defined
1645 && hi->root.type != bfd_link_hash_defweak)
1646 (*_bfd_error_handler)
1647 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1648 abfd, shortname);
1649 }
1650 else
1651 {
1652 bh = &hi->root;
1653 if (! (_bfd_generic_link_add_one_symbol
1654 (info, abfd, shortname, BSF_INDIRECT,
1655 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1656 return FALSE;
1657 hi = (struct elf_link_hash_entry *) bh;
1658
1659 /* If there is a duplicate definition somewhere, then HI may not
1660 point to an indirect symbol. We will have reported an error
1661 to the user in that case. */
1662
1663 if (hi->root.type == bfd_link_hash_indirect)
1664 {
1665 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
1666
1667 /* See if the new flags lead us to realize that the symbol
1668 must be dynamic. */
1669 if (! *dynsym)
1670 {
1671 if (! dynamic)
1672 {
1673 if (info->shared
1674 || hi->ref_dynamic)
1675 *dynsym = TRUE;
1676 }
1677 else
1678 {
1679 if (hi->ref_regular)
1680 *dynsym = TRUE;
1681 }
1682 }
1683 }
1684 }
1685
1686 return TRUE;
1687 }
1688
1689 /* This routine is used to export all defined symbols into the dynamic
1690 symbol table. It is called via elf_link_hash_traverse. */
1691
1692 bfd_boolean
_bfd_elf_export_symbol(struct elf_link_hash_entry * h,void * data)1693 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1694 {
1695 struct elf_info_failed *eif = data;
1696
1697 /* Ignore this if we won't export it. */
1698 if (!eif->info->export_dynamic && !h->dynamic)
1699 return TRUE;
1700
1701 /* Ignore indirect symbols. These are added by the versioning code. */
1702 if (h->root.type == bfd_link_hash_indirect)
1703 return TRUE;
1704
1705 if (h->root.type == bfd_link_hash_warning)
1706 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1707
1708 if (h->dynindx == -1
1709 && (h->def_regular
1710 || h->ref_regular))
1711 {
1712 struct bfd_elf_version_tree *t;
1713 struct bfd_elf_version_expr *d;
1714
1715 for (t = eif->verdefs; t != NULL; t = t->next)
1716 {
1717 if (t->globals.list != NULL)
1718 {
1719 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1720 if (d != NULL)
1721 goto doit;
1722 }
1723
1724 if (t->locals.list != NULL)
1725 {
1726 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1727 if (d != NULL)
1728 return TRUE;
1729 }
1730 }
1731
1732 if (!eif->verdefs)
1733 {
1734 doit:
1735 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1736 {
1737 eif->failed = TRUE;
1738 return FALSE;
1739 }
1740 }
1741 }
1742
1743 return TRUE;
1744 }
1745
1746 /* Look through the symbols which are defined in other shared
1747 libraries and referenced here. Update the list of version
1748 dependencies. This will be put into the .gnu.version_r section.
1749 This function is called via elf_link_hash_traverse. */
1750
1751 bfd_boolean
_bfd_elf_link_find_version_dependencies(struct elf_link_hash_entry * h,void * data)1752 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1753 void *data)
1754 {
1755 struct elf_find_verdep_info *rinfo = data;
1756 Elf_Internal_Verneed *t;
1757 Elf_Internal_Vernaux *a;
1758 bfd_size_type amt;
1759
1760 if (h->root.type == bfd_link_hash_warning)
1761 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1762
1763 /* We only care about symbols defined in shared objects with version
1764 information. */
1765 if (!h->def_dynamic
1766 || h->def_regular
1767 || h->dynindx == -1
1768 || h->verinfo.verdef == NULL)
1769 return TRUE;
1770
1771 /* See if we already know about this version. */
1772 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1773 {
1774 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1775 continue;
1776
1777 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1778 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1779 return TRUE;
1780
1781 break;
1782 }
1783
1784 /* This is a new version. Add it to tree we are building. */
1785
1786 if (t == NULL)
1787 {
1788 amt = sizeof *t;
1789 t = bfd_zalloc (rinfo->output_bfd, amt);
1790 if (t == NULL)
1791 {
1792 rinfo->failed = TRUE;
1793 return FALSE;
1794 }
1795
1796 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1797 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1798 elf_tdata (rinfo->output_bfd)->verref = t;
1799 }
1800
1801 amt = sizeof *a;
1802 a = bfd_zalloc (rinfo->output_bfd, amt);
1803
1804 /* Note that we are copying a string pointer here, and testing it
1805 above. If bfd_elf_string_from_elf_section is ever changed to
1806 discard the string data when low in memory, this will have to be
1807 fixed. */
1808 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1809
1810 a->vna_flags = h->verinfo.verdef->vd_flags;
1811 a->vna_nextptr = t->vn_auxptr;
1812
1813 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1814 ++rinfo->vers;
1815
1816 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1817
1818 t->vn_auxptr = a;
1819
1820 return TRUE;
1821 }
1822
1823 /* Figure out appropriate versions for all the symbols. We may not
1824 have the version number script until we have read all of the input
1825 files, so until that point we don't know which symbols should be
1826 local. This function is called via elf_link_hash_traverse. */
1827
1828 bfd_boolean
_bfd_elf_link_assign_sym_version(struct elf_link_hash_entry * h,void * data)1829 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1830 {
1831 struct elf_assign_sym_version_info *sinfo;
1832 struct bfd_link_info *info;
1833 const struct elf_backend_data *bed;
1834 struct elf_info_failed eif;
1835 char *p;
1836 bfd_size_type amt;
1837
1838 sinfo = data;
1839 info = sinfo->info;
1840
1841 if (h->root.type == bfd_link_hash_warning)
1842 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1843
1844 /* Fix the symbol flags. */
1845 eif.failed = FALSE;
1846 eif.info = info;
1847 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1848 {
1849 if (eif.failed)
1850 sinfo->failed = TRUE;
1851 return FALSE;
1852 }
1853
1854 /* We only need version numbers for symbols defined in regular
1855 objects. */
1856 if (!h->def_regular)
1857 return TRUE;
1858
1859 bed = get_elf_backend_data (sinfo->output_bfd);
1860 p = strchr (h->root.root.string, ELF_VER_CHR);
1861 if (p != NULL && h->verinfo.vertree == NULL)
1862 {
1863 struct bfd_elf_version_tree *t;
1864 bfd_boolean hidden;
1865
1866 hidden = TRUE;
1867
1868 /* There are two consecutive ELF_VER_CHR characters if this is
1869 not a hidden symbol. */
1870 ++p;
1871 if (*p == ELF_VER_CHR)
1872 {
1873 hidden = FALSE;
1874 ++p;
1875 }
1876
1877 /* If there is no version string, we can just return out. */
1878 if (*p == '\0')
1879 {
1880 if (hidden)
1881 h->hidden = 1;
1882 return TRUE;
1883 }
1884
1885 /* Look for the version. If we find it, it is no longer weak. */
1886 for (t = sinfo->verdefs; t != NULL; t = t->next)
1887 {
1888 if (strcmp (t->name, p) == 0)
1889 {
1890 size_t len;
1891 char *alc;
1892 struct bfd_elf_version_expr *d;
1893
1894 len = p - h->root.root.string;
1895 alc = bfd_malloc (len);
1896 if (alc == NULL)
1897 return FALSE;
1898 memcpy (alc, h->root.root.string, len - 1);
1899 alc[len - 1] = '\0';
1900 if (alc[len - 2] == ELF_VER_CHR)
1901 alc[len - 2] = '\0';
1902
1903 h->verinfo.vertree = t;
1904 t->used = TRUE;
1905 d = NULL;
1906
1907 if (t->globals.list != NULL)
1908 d = (*t->match) (&t->globals, NULL, alc);
1909
1910 /* See if there is anything to force this symbol to
1911 local scope. */
1912 if (d == NULL && t->locals.list != NULL)
1913 {
1914 d = (*t->match) (&t->locals, NULL, alc);
1915 if (d != NULL
1916 && h->dynindx != -1
1917 && ! info->export_dynamic)
1918 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1919 }
1920
1921 free (alc);
1922 break;
1923 }
1924 }
1925
1926 /* If we are building an application, we need to create a
1927 version node for this version. */
1928 if (t == NULL && info->executable)
1929 {
1930 struct bfd_elf_version_tree **pp;
1931 int version_index;
1932
1933 /* If we aren't going to export this symbol, we don't need
1934 to worry about it. */
1935 if (h->dynindx == -1)
1936 return TRUE;
1937
1938 amt = sizeof *t;
1939 t = bfd_zalloc (sinfo->output_bfd, amt);
1940 if (t == NULL)
1941 {
1942 sinfo->failed = TRUE;
1943 return FALSE;
1944 }
1945
1946 t->name = p;
1947 t->name_indx = (unsigned int) -1;
1948 t->used = TRUE;
1949
1950 version_index = 1;
1951 /* Don't count anonymous version tag. */
1952 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1953 version_index = 0;
1954 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1955 ++version_index;
1956 t->vernum = version_index;
1957
1958 *pp = t;
1959
1960 h->verinfo.vertree = t;
1961 }
1962 else if (t == NULL)
1963 {
1964 /* We could not find the version for a symbol when
1965 generating a shared archive. Return an error. */
1966 (*_bfd_error_handler)
1967 (_("%B: version node not found for symbol %s"),
1968 sinfo->output_bfd, h->root.root.string);
1969 bfd_set_error (bfd_error_bad_value);
1970 sinfo->failed = TRUE;
1971 return FALSE;
1972 }
1973
1974 if (hidden)
1975 h->hidden = 1;
1976 }
1977
1978 /* If we don't have a version for this symbol, see if we can find
1979 something. */
1980 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1981 {
1982 struct bfd_elf_version_tree *t;
1983 struct bfd_elf_version_tree *local_ver;
1984 struct bfd_elf_version_expr *d;
1985
1986 /* See if can find what version this symbol is in. If the
1987 symbol is supposed to be local, then don't actually register
1988 it. */
1989 local_ver = NULL;
1990 for (t = sinfo->verdefs; t != NULL; t = t->next)
1991 {
1992 if (t->globals.list != NULL)
1993 {
1994 bfd_boolean matched;
1995
1996 matched = FALSE;
1997 d = NULL;
1998 while ((d = (*t->match) (&t->globals, d,
1999 h->root.root.string)) != NULL)
2000 if (d->symver)
2001 matched = TRUE;
2002 else
2003 {
2004 /* There is a version without definition. Make
2005 the symbol the default definition for this
2006 version. */
2007 h->verinfo.vertree = t;
2008 local_ver = NULL;
2009 d->script = 1;
2010 break;
2011 }
2012 if (d != NULL)
2013 break;
2014 else if (matched)
2015 /* There is no undefined version for this symbol. Hide the
2016 default one. */
2017 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
2018 }
2019
2020 if (t->locals.list != NULL)
2021 {
2022 d = NULL;
2023 while ((d = (*t->match) (&t->locals, d,
2024 h->root.root.string)) != NULL)
2025 {
2026 local_ver = t;
2027 /* If the match is "*", keep looking for a more
2028 explicit, perhaps even global, match.
2029 XXX: Shouldn't this be !d->wildcard instead? */
2030 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
2031 break;
2032 }
2033
2034 if (d != NULL)
2035 break;
2036 }
2037 }
2038
2039 if (local_ver != NULL)
2040 {
2041 h->verinfo.vertree = local_ver;
2042 if (h->dynindx != -1
2043 && ! info->export_dynamic)
2044 {
2045 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
2046 }
2047 }
2048 }
2049
2050 return TRUE;
2051 }
2052
2053 /* Read and swap the relocs from the section indicated by SHDR. This
2054 may be either a REL or a RELA section. The relocations are
2055 translated into RELA relocations and stored in INTERNAL_RELOCS,
2056 which should have already been allocated to contain enough space.
2057 The EXTERNAL_RELOCS are a buffer where the external form of the
2058 relocations should be stored.
2059
2060 Returns FALSE if something goes wrong. */
2061
2062 static bfd_boolean
elf_link_read_relocs_from_section(bfd * abfd,asection * sec,Elf_Internal_Shdr * shdr,void * external_relocs,Elf_Internal_Rela * internal_relocs)2063 elf_link_read_relocs_from_section (bfd *abfd,
2064 asection *sec,
2065 Elf_Internal_Shdr *shdr,
2066 void *external_relocs,
2067 Elf_Internal_Rela *internal_relocs)
2068 {
2069 const struct elf_backend_data *bed;
2070 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
2071 const bfd_byte *erela;
2072 const bfd_byte *erelaend;
2073 Elf_Internal_Rela *irela;
2074 Elf_Internal_Shdr *symtab_hdr;
2075 size_t nsyms;
2076
2077 /* Position ourselves at the start of the section. */
2078 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2079 return FALSE;
2080
2081 /* Read the relocations. */
2082 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
2083 return FALSE;
2084
2085 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2086 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
2087
2088 bed = get_elf_backend_data (abfd);
2089
2090 /* Convert the external relocations to the internal format. */
2091 if (shdr->sh_entsize == bed->s->sizeof_rel)
2092 swap_in = bed->s->swap_reloc_in;
2093 else if (shdr->sh_entsize == bed->s->sizeof_rela)
2094 swap_in = bed->s->swap_reloca_in;
2095 else
2096 {
2097 bfd_set_error (bfd_error_wrong_format);
2098 return FALSE;
2099 }
2100
2101 erela = external_relocs;
2102 erelaend = erela + shdr->sh_size;
2103 irela = internal_relocs;
2104 while (erela < erelaend)
2105 {
2106 bfd_vma r_symndx;
2107
2108 (*swap_in) (abfd, erela, irela);
2109 r_symndx = ELF32_R_SYM (irela->r_info);
2110 if (bed->s->arch_size == 64)
2111 r_symndx >>= 24;
2112 if ((size_t) r_symndx >= nsyms)
2113 {
2114 (*_bfd_error_handler)
2115 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
2116 " for offset 0x%lx in section `%A'"),
2117 abfd, sec,
2118 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
2119 bfd_set_error (bfd_error_bad_value);
2120 return FALSE;
2121 }
2122 irela += bed->s->int_rels_per_ext_rel;
2123 erela += shdr->sh_entsize;
2124 }
2125
2126 return TRUE;
2127 }
2128
2129 /* Read and swap the relocs for a section O. They may have been
2130 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2131 not NULL, they are used as buffers to read into. They are known to
2132 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2133 the return value is allocated using either malloc or bfd_alloc,
2134 according to the KEEP_MEMORY argument. If O has two relocation
2135 sections (both REL and RELA relocations), then the REL_HDR
2136 relocations will appear first in INTERNAL_RELOCS, followed by the
2137 REL_HDR2 relocations. */
2138
2139 Elf_Internal_Rela *
_bfd_elf_link_read_relocs(bfd * abfd,asection * o,void * external_relocs,Elf_Internal_Rela * internal_relocs,bfd_boolean keep_memory)2140 _bfd_elf_link_read_relocs (bfd *abfd,
2141 asection *o,
2142 void *external_relocs,
2143 Elf_Internal_Rela *internal_relocs,
2144 bfd_boolean keep_memory)
2145 {
2146 Elf_Internal_Shdr *rel_hdr;
2147 void *alloc1 = NULL;
2148 Elf_Internal_Rela *alloc2 = NULL;
2149 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2150
2151 if (elf_section_data (o)->relocs != NULL)
2152 return elf_section_data (o)->relocs;
2153
2154 if (o->reloc_count == 0)
2155 return NULL;
2156
2157 rel_hdr = &elf_section_data (o)->rel_hdr;
2158
2159 if (internal_relocs == NULL)
2160 {
2161 bfd_size_type size;
2162
2163 size = o->reloc_count;
2164 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2165 if (keep_memory)
2166 internal_relocs = bfd_alloc (abfd, size);
2167 else
2168 internal_relocs = alloc2 = bfd_malloc (size);
2169 if (internal_relocs == NULL)
2170 goto error_return;
2171 }
2172
2173 if (external_relocs == NULL)
2174 {
2175 bfd_size_type size = rel_hdr->sh_size;
2176
2177 if (elf_section_data (o)->rel_hdr2)
2178 size += elf_section_data (o)->rel_hdr2->sh_size;
2179 alloc1 = bfd_malloc (size);
2180 if (alloc1 == NULL)
2181 goto error_return;
2182 external_relocs = alloc1;
2183 }
2184
2185 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2186 external_relocs,
2187 internal_relocs))
2188 goto error_return;
2189 if (elf_section_data (o)->rel_hdr2
2190 && (!elf_link_read_relocs_from_section
2191 (abfd, o,
2192 elf_section_data (o)->rel_hdr2,
2193 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2194 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2195 * bed->s->int_rels_per_ext_rel))))
2196 goto error_return;
2197
2198 /* Cache the results for next time, if we can. */
2199 if (keep_memory)
2200 elf_section_data (o)->relocs = internal_relocs;
2201
2202 if (alloc1 != NULL)
2203 free (alloc1);
2204
2205 /* Don't free alloc2, since if it was allocated we are passing it
2206 back (under the name of internal_relocs). */
2207
2208 return internal_relocs;
2209
2210 error_return:
2211 if (alloc1 != NULL)
2212 free (alloc1);
2213 if (alloc2 != NULL)
2214 free (alloc2);
2215 return NULL;
2216 }
2217
2218 /* Compute the size of, and allocate space for, REL_HDR which is the
2219 section header for a section containing relocations for O. */
2220
2221 bfd_boolean
_bfd_elf_link_size_reloc_section(bfd * abfd,Elf_Internal_Shdr * rel_hdr,asection * o)2222 _bfd_elf_link_size_reloc_section (bfd *abfd,
2223 Elf_Internal_Shdr *rel_hdr,
2224 asection *o)
2225 {
2226 bfd_size_type reloc_count;
2227 bfd_size_type num_rel_hashes;
2228
2229 /* Figure out how many relocations there will be. */
2230 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2231 reloc_count = elf_section_data (o)->rel_count;
2232 else
2233 reloc_count = elf_section_data (o)->rel_count2;
2234
2235 num_rel_hashes = o->reloc_count;
2236 if (num_rel_hashes < reloc_count)
2237 num_rel_hashes = reloc_count;
2238
2239 /* That allows us to calculate the size of the section. */
2240 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2241
2242 /* The contents field must last into write_object_contents, so we
2243 allocate it with bfd_alloc rather than malloc. Also since we
2244 cannot be sure that the contents will actually be filled in,
2245 we zero the allocated space. */
2246 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2247 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2248 return FALSE;
2249
2250 /* We only allocate one set of hash entries, so we only do it the
2251 first time we are called. */
2252 if (elf_section_data (o)->rel_hashes == NULL
2253 && num_rel_hashes)
2254 {
2255 struct elf_link_hash_entry **p;
2256
2257 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2258 if (p == NULL)
2259 return FALSE;
2260
2261 elf_section_data (o)->rel_hashes = p;
2262 }
2263
2264 return TRUE;
2265 }
2266
2267 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2268 originated from the section given by INPUT_REL_HDR) to the
2269 OUTPUT_BFD. */
2270
2271 bfd_boolean
_bfd_elf_link_output_relocs(bfd * output_bfd,asection * input_section,Elf_Internal_Shdr * input_rel_hdr,Elf_Internal_Rela * internal_relocs,struct elf_link_hash_entry ** rel_hash ATTRIBUTE_UNUSED)2272 _bfd_elf_link_output_relocs (bfd *output_bfd,
2273 asection *input_section,
2274 Elf_Internal_Shdr *input_rel_hdr,
2275 Elf_Internal_Rela *internal_relocs,
2276 struct elf_link_hash_entry **rel_hash
2277 ATTRIBUTE_UNUSED)
2278 {
2279 Elf_Internal_Rela *irela;
2280 Elf_Internal_Rela *irelaend;
2281 bfd_byte *erel;
2282 Elf_Internal_Shdr *output_rel_hdr;
2283 asection *output_section;
2284 unsigned int *rel_countp = NULL;
2285 const struct elf_backend_data *bed;
2286 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2287
2288 output_section = input_section->output_section;
2289 output_rel_hdr = NULL;
2290
2291 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2292 == input_rel_hdr->sh_entsize)
2293 {
2294 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2295 rel_countp = &elf_section_data (output_section)->rel_count;
2296 }
2297 else if (elf_section_data (output_section)->rel_hdr2
2298 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2299 == input_rel_hdr->sh_entsize))
2300 {
2301 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2302 rel_countp = &elf_section_data (output_section)->rel_count2;
2303 }
2304 else
2305 {
2306 (*_bfd_error_handler)
2307 (_("%B: relocation size mismatch in %B section %A"),
2308 output_bfd, input_section->owner, input_section);
2309 bfd_set_error (bfd_error_wrong_object_format);
2310 return FALSE;
2311 }
2312
2313 bed = get_elf_backend_data (output_bfd);
2314 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2315 swap_out = bed->s->swap_reloc_out;
2316 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2317 swap_out = bed->s->swap_reloca_out;
2318 else
2319 abort ();
2320
2321 erel = output_rel_hdr->contents;
2322 erel += *rel_countp * input_rel_hdr->sh_entsize;
2323 irela = internal_relocs;
2324 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2325 * bed->s->int_rels_per_ext_rel);
2326 while (irela < irelaend)
2327 {
2328 (*swap_out) (output_bfd, irela, erel);
2329 irela += bed->s->int_rels_per_ext_rel;
2330 erel += input_rel_hdr->sh_entsize;
2331 }
2332
2333 /* Bump the counter, so that we know where to add the next set of
2334 relocations. */
2335 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2336
2337 return TRUE;
2338 }
2339
2340 /* Make weak undefined symbols in PIE dynamic. */
2341
2342 bfd_boolean
_bfd_elf_link_hash_fixup_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)2343 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2344 struct elf_link_hash_entry *h)
2345 {
2346 if (info->pie
2347 && h->dynindx == -1
2348 && h->root.type == bfd_link_hash_undefweak)
2349 return bfd_elf_link_record_dynamic_symbol (info, h);
2350
2351 return TRUE;
2352 }
2353
2354 /* Fix up the flags for a symbol. This handles various cases which
2355 can only be fixed after all the input files are seen. This is
2356 currently called by both adjust_dynamic_symbol and
2357 assign_sym_version, which is unnecessary but perhaps more robust in
2358 the face of future changes. */
2359
2360 bfd_boolean
_bfd_elf_fix_symbol_flags(struct elf_link_hash_entry * h,struct elf_info_failed * eif)2361 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2362 struct elf_info_failed *eif)
2363 {
2364 const struct elf_backend_data *bed = NULL;
2365
2366 /* If this symbol was mentioned in a non-ELF file, try to set
2367 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2368 permit a non-ELF file to correctly refer to a symbol defined in
2369 an ELF dynamic object. */
2370 if (h->non_elf)
2371 {
2372 while (h->root.type == bfd_link_hash_indirect)
2373 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2374
2375 if (h->root.type != bfd_link_hash_defined
2376 && h->root.type != bfd_link_hash_defweak)
2377 {
2378 h->ref_regular = 1;
2379 h->ref_regular_nonweak = 1;
2380 }
2381 else
2382 {
2383 if (h->root.u.def.section->owner != NULL
2384 && (bfd_get_flavour (h->root.u.def.section->owner)
2385 == bfd_target_elf_flavour))
2386 {
2387 h->ref_regular = 1;
2388 h->ref_regular_nonweak = 1;
2389 }
2390 else
2391 h->def_regular = 1;
2392 }
2393
2394 if (h->dynindx == -1
2395 && (h->def_dynamic
2396 || h->ref_dynamic))
2397 {
2398 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2399 {
2400 eif->failed = TRUE;
2401 return FALSE;
2402 }
2403 }
2404 }
2405 else
2406 {
2407 /* Unfortunately, NON_ELF is only correct if the symbol
2408 was first seen in a non-ELF file. Fortunately, if the symbol
2409 was first seen in an ELF file, we're probably OK unless the
2410 symbol was defined in a non-ELF file. Catch that case here.
2411 FIXME: We're still in trouble if the symbol was first seen in
2412 a dynamic object, and then later in a non-ELF regular object. */
2413 if ((h->root.type == bfd_link_hash_defined
2414 || h->root.type == bfd_link_hash_defweak)
2415 && !h->def_regular
2416 && (h->root.u.def.section->owner != NULL
2417 ? (bfd_get_flavour (h->root.u.def.section->owner)
2418 != bfd_target_elf_flavour)
2419 : (bfd_is_abs_section (h->root.u.def.section)
2420 && !h->def_dynamic)))
2421 h->def_regular = 1;
2422 }
2423
2424 /* Backend specific symbol fixup. */
2425 if (elf_hash_table (eif->info)->dynobj)
2426 {
2427 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2428 if (bed->elf_backend_fixup_symbol
2429 && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
2430 return FALSE;
2431 }
2432
2433 /* If this is a final link, and the symbol was defined as a common
2434 symbol in a regular object file, and there was no definition in
2435 any dynamic object, then the linker will have allocated space for
2436 the symbol in a common section but the DEF_REGULAR
2437 flag will not have been set. */
2438 if (h->root.type == bfd_link_hash_defined
2439 && !h->def_regular
2440 && h->ref_regular
2441 && !h->def_dynamic
2442 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2443 h->def_regular = 1;
2444
2445 /* If -Bsymbolic was used (which means to bind references to global
2446 symbols to the definition within the shared object), and this
2447 symbol was defined in a regular object, then it actually doesn't
2448 need a PLT entry. Likewise, if the symbol has non-default
2449 visibility. If the symbol has hidden or internal visibility, we
2450 will force it local. */
2451 if (h->needs_plt
2452 && eif->info->shared
2453 && is_elf_hash_table (eif->info->hash)
2454 && (SYMBOLIC_BIND (eif->info, h)
2455 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2456 && h->def_regular)
2457 {
2458 bfd_boolean force_local;
2459
2460 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2461 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2462 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2463 }
2464
2465 /* If a weak undefined symbol has non-default visibility, we also
2466 hide it from the dynamic linker. */
2467 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2468 && h->root.type == bfd_link_hash_undefweak)
2469 {
2470 const struct elf_backend_data *bed;
2471 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2472 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2473 }
2474
2475 /* If this is a weak defined symbol in a dynamic object, and we know
2476 the real definition in the dynamic object, copy interesting flags
2477 over to the real definition. */
2478 if (h->u.weakdef != NULL)
2479 {
2480 struct elf_link_hash_entry *weakdef;
2481
2482 weakdef = h->u.weakdef;
2483 if (h->root.type == bfd_link_hash_indirect)
2484 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2485
2486 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2487 || h->root.type == bfd_link_hash_defweak);
2488 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2489 || weakdef->root.type == bfd_link_hash_defweak);
2490 BFD_ASSERT (weakdef->def_dynamic);
2491
2492 /* If the real definition is defined by a regular object file,
2493 don't do anything special. See the longer description in
2494 _bfd_elf_adjust_dynamic_symbol, below. */
2495 if (weakdef->def_regular)
2496 h->u.weakdef = NULL;
2497 else
2498 (*bed->elf_backend_copy_indirect_symbol) (eif->info, weakdef,
2499 h);
2500 }
2501
2502 return TRUE;
2503 }
2504
2505 /* Make the backend pick a good value for a dynamic symbol. This is
2506 called via elf_link_hash_traverse, and also calls itself
2507 recursively. */
2508
2509 bfd_boolean
_bfd_elf_adjust_dynamic_symbol(struct elf_link_hash_entry * h,void * data)2510 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2511 {
2512 struct elf_info_failed *eif = data;
2513 bfd *dynobj;
2514 const struct elf_backend_data *bed;
2515
2516 if (! is_elf_hash_table (eif->info->hash))
2517 return FALSE;
2518
2519 if (h->root.type == bfd_link_hash_warning)
2520 {
2521 h->got = elf_hash_table (eif->info)->init_got_offset;
2522 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2523
2524 /* When warning symbols are created, they **replace** the "real"
2525 entry in the hash table, thus we never get to see the real
2526 symbol in a hash traversal. So look at it now. */
2527 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2528 }
2529
2530 /* Ignore indirect symbols. These are added by the versioning code. */
2531 if (h->root.type == bfd_link_hash_indirect)
2532 return TRUE;
2533
2534 /* Fix the symbol flags. */
2535 if (! _bfd_elf_fix_symbol_flags (h, eif))
2536 return FALSE;
2537
2538 /* If this symbol does not require a PLT entry, and it is not
2539 defined by a dynamic object, or is not referenced by a regular
2540 object, ignore it. We do have to handle a weak defined symbol,
2541 even if no regular object refers to it, if we decided to add it
2542 to the dynamic symbol table. FIXME: Do we normally need to worry
2543 about symbols which are defined by one dynamic object and
2544 referenced by another one? */
2545 if (!h->needs_plt
2546 && (h->def_regular
2547 || !h->def_dynamic
2548 || (!h->ref_regular
2549 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2550 {
2551 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2552 return TRUE;
2553 }
2554
2555 /* If we've already adjusted this symbol, don't do it again. This
2556 can happen via a recursive call. */
2557 if (h->dynamic_adjusted)
2558 return TRUE;
2559
2560 /* Don't look at this symbol again. Note that we must set this
2561 after checking the above conditions, because we may look at a
2562 symbol once, decide not to do anything, and then get called
2563 recursively later after REF_REGULAR is set below. */
2564 h->dynamic_adjusted = 1;
2565
2566 /* If this is a weak definition, and we know a real definition, and
2567 the real symbol is not itself defined by a regular object file,
2568 then get a good value for the real definition. We handle the
2569 real symbol first, for the convenience of the backend routine.
2570
2571 Note that there is a confusing case here. If the real definition
2572 is defined by a regular object file, we don't get the real symbol
2573 from the dynamic object, but we do get the weak symbol. If the
2574 processor backend uses a COPY reloc, then if some routine in the
2575 dynamic object changes the real symbol, we will not see that
2576 change in the corresponding weak symbol. This is the way other
2577 ELF linkers work as well, and seems to be a result of the shared
2578 library model.
2579
2580 I will clarify this issue. Most SVR4 shared libraries define the
2581 variable _timezone and define timezone as a weak synonym. The
2582 tzset call changes _timezone. If you write
2583 extern int timezone;
2584 int _timezone = 5;
2585 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2586 you might expect that, since timezone is a synonym for _timezone,
2587 the same number will print both times. However, if the processor
2588 backend uses a COPY reloc, then actually timezone will be copied
2589 into your process image, and, since you define _timezone
2590 yourself, _timezone will not. Thus timezone and _timezone will
2591 wind up at different memory locations. The tzset call will set
2592 _timezone, leaving timezone unchanged. */
2593
2594 if (h->u.weakdef != NULL)
2595 {
2596 /* If we get to this point, we know there is an implicit
2597 reference by a regular object file via the weak symbol H.
2598 FIXME: Is this really true? What if the traversal finds
2599 H->U.WEAKDEF before it finds H? */
2600 h->u.weakdef->ref_regular = 1;
2601
2602 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2603 return FALSE;
2604 }
2605
2606 /* If a symbol has no type and no size and does not require a PLT
2607 entry, then we are probably about to do the wrong thing here: we
2608 are probably going to create a COPY reloc for an empty object.
2609 This case can arise when a shared object is built with assembly
2610 code, and the assembly code fails to set the symbol type. */
2611 if (h->size == 0
2612 && h->type == STT_NOTYPE
2613 && !h->needs_plt)
2614 (*_bfd_error_handler)
2615 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2616 h->root.root.string);
2617
2618 dynobj = elf_hash_table (eif->info)->dynobj;
2619 bed = get_elf_backend_data (dynobj);
2620 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2621 {
2622 eif->failed = TRUE;
2623 return FALSE;
2624 }
2625
2626 return TRUE;
2627 }
2628
2629 /* Adjust the dynamic symbol, H, for copy in the dynamic bss section,
2630 DYNBSS. */
2631
2632 bfd_boolean
_bfd_elf_adjust_dynamic_copy(struct elf_link_hash_entry * h,asection * dynbss)2633 _bfd_elf_adjust_dynamic_copy (struct elf_link_hash_entry *h,
2634 asection *dynbss)
2635 {
2636 unsigned int power_of_two;
2637 bfd_vma mask;
2638 asection *sec = h->root.u.def.section;
2639
2640 /* The section aligment of definition is the maximum alignment
2641 requirement of symbols defined in the section. Since we don't
2642 know the symbol alignment requirement, we start with the
2643 maximum alignment and check low bits of the symbol address
2644 for the minimum alignment. */
2645 power_of_two = bfd_get_section_alignment (sec->owner, sec);
2646 mask = ((bfd_vma) 1 << power_of_two) - 1;
2647 while ((h->root.u.def.value & mask) != 0)
2648 {
2649 mask >>= 1;
2650 --power_of_two;
2651 }
2652
2653 if (power_of_two > bfd_get_section_alignment (dynbss->owner,
2654 dynbss))
2655 {
2656 /* Adjust the section alignment if needed. */
2657 if (! bfd_set_section_alignment (dynbss->owner, dynbss,
2658 power_of_two))
2659 return FALSE;
2660 }
2661
2662 /* We make sure that the symbol will be aligned properly. */
2663 dynbss->size = BFD_ALIGN (dynbss->size, mask + 1);
2664
2665 /* Define the symbol as being at this point in DYNBSS. */
2666 h->root.u.def.section = dynbss;
2667 h->root.u.def.value = dynbss->size;
2668
2669 /* Increment the size of DYNBSS to make room for the symbol. */
2670 dynbss->size += h->size;
2671
2672 return TRUE;
2673 }
2674
2675 /* Adjust all external symbols pointing into SEC_MERGE sections
2676 to reflect the object merging within the sections. */
2677
2678 bfd_boolean
_bfd_elf_link_sec_merge_syms(struct elf_link_hash_entry * h,void * data)2679 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2680 {
2681 asection *sec;
2682
2683 if (h->root.type == bfd_link_hash_warning)
2684 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2685
2686 if ((h->root.type == bfd_link_hash_defined
2687 || h->root.type == bfd_link_hash_defweak)
2688 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2689 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2690 {
2691 bfd *output_bfd = data;
2692
2693 h->root.u.def.value =
2694 _bfd_merged_section_offset (output_bfd,
2695 &h->root.u.def.section,
2696 elf_section_data (sec)->sec_info,
2697 h->root.u.def.value);
2698 }
2699
2700 return TRUE;
2701 }
2702
2703 /* Returns false if the symbol referred to by H should be considered
2704 to resolve local to the current module, and true if it should be
2705 considered to bind dynamically. */
2706
2707 bfd_boolean
_bfd_elf_dynamic_symbol_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bfd_boolean ignore_protected)2708 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2709 struct bfd_link_info *info,
2710 bfd_boolean ignore_protected)
2711 {
2712 bfd_boolean binding_stays_local_p;
2713 const struct elf_backend_data *bed;
2714 struct elf_link_hash_table *hash_table;
2715
2716 if (h == NULL)
2717 return FALSE;
2718
2719 while (h->root.type == bfd_link_hash_indirect
2720 || h->root.type == bfd_link_hash_warning)
2721 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2722
2723 /* If it was forced local, then clearly it's not dynamic. */
2724 if (h->dynindx == -1)
2725 return FALSE;
2726 if (h->forced_local)
2727 return FALSE;
2728
2729 /* Identify the cases where name binding rules say that a
2730 visible symbol resolves locally. */
2731 binding_stays_local_p = info->executable || SYMBOLIC_BIND (info, h);
2732
2733 switch (ELF_ST_VISIBILITY (h->other))
2734 {
2735 case STV_INTERNAL:
2736 case STV_HIDDEN:
2737 return FALSE;
2738
2739 case STV_PROTECTED:
2740 hash_table = elf_hash_table (info);
2741 if (!is_elf_hash_table (hash_table))
2742 return FALSE;
2743
2744 bed = get_elf_backend_data (hash_table->dynobj);
2745
2746 /* Proper resolution for function pointer equality may require
2747 that these symbols perhaps be resolved dynamically, even though
2748 we should be resolving them to the current module. */
2749 if (!ignore_protected || !bed->is_function_type (h->type))
2750 binding_stays_local_p = TRUE;
2751 break;
2752
2753 default:
2754 break;
2755 }
2756
2757 /* If it isn't defined locally, then clearly it's dynamic. */
2758 if (!h->def_regular)
2759 return TRUE;
2760
2761 /* Otherwise, the symbol is dynamic if binding rules don't tell
2762 us that it remains local. */
2763 return !binding_stays_local_p;
2764 }
2765
2766 /* Return true if the symbol referred to by H should be considered
2767 to resolve local to the current module, and false otherwise. Differs
2768 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2769 undefined symbols and weak symbols. */
2770
2771 bfd_boolean
_bfd_elf_symbol_refs_local_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bfd_boolean local_protected)2772 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2773 struct bfd_link_info *info,
2774 bfd_boolean local_protected)
2775 {
2776 const struct elf_backend_data *bed;
2777 struct elf_link_hash_table *hash_table;
2778
2779 /* If it's a local sym, of course we resolve locally. */
2780 if (h == NULL)
2781 return TRUE;
2782
2783 /* Common symbols that become definitions don't get the DEF_REGULAR
2784 flag set, so test it first, and don't bail out. */
2785 if (ELF_COMMON_DEF_P (h))
2786 /* Do nothing. */;
2787 /* If we don't have a definition in a regular file, then we can't
2788 resolve locally. The sym is either undefined or dynamic. */
2789 else if (!h->def_regular)
2790 return FALSE;
2791
2792 /* Forced local symbols resolve locally. */
2793 if (h->forced_local)
2794 return TRUE;
2795
2796 /* As do non-dynamic symbols. */
2797 if (h->dynindx == -1)
2798 return TRUE;
2799
2800 /* At this point, we know the symbol is defined and dynamic. In an
2801 executable it must resolve locally, likewise when building symbolic
2802 shared libraries. */
2803 if (info->executable || SYMBOLIC_BIND (info, h))
2804 return TRUE;
2805
2806 /* Now deal with defined dynamic symbols in shared libraries. Ones
2807 with default visibility might not resolve locally. */
2808 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2809 return FALSE;
2810
2811 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2812 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2813 return TRUE;
2814
2815 hash_table = elf_hash_table (info);
2816 if (!is_elf_hash_table (hash_table))
2817 return TRUE;
2818
2819 bed = get_elf_backend_data (hash_table->dynobj);
2820
2821 /* STV_PROTECTED non-function symbols are local. */
2822 if (!bed->is_function_type (h->type))
2823 return TRUE;
2824
2825 /* Function pointer equality tests may require that STV_PROTECTED
2826 symbols be treated as dynamic symbols, even when we know that the
2827 dynamic linker will resolve them locally. */
2828 return local_protected;
2829 }
2830
2831 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2832 aligned. Returns the first TLS output section. */
2833
2834 struct bfd_section *
_bfd_elf_tls_setup(bfd * obfd,struct bfd_link_info * info)2835 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2836 {
2837 struct bfd_section *sec, *tls;
2838 unsigned int align = 0;
2839
2840 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2841 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2842 break;
2843 tls = sec;
2844
2845 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2846 if (sec->alignment_power > align)
2847 align = sec->alignment_power;
2848
2849 elf_hash_table (info)->tls_sec = tls;
2850
2851 /* Ensure the alignment of the first section is the largest alignment,
2852 so that the tls segment starts aligned. */
2853 if (tls != NULL)
2854 tls->alignment_power = align;
2855
2856 return tls;
2857 }
2858
2859 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2860 static bfd_boolean
is_global_data_symbol_definition(bfd * abfd ATTRIBUTE_UNUSED,Elf_Internal_Sym * sym)2861 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2862 Elf_Internal_Sym *sym)
2863 {
2864 const struct elf_backend_data *bed;
2865
2866 /* Local symbols do not count, but target specific ones might. */
2867 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2868 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2869 return FALSE;
2870
2871 bed = get_elf_backend_data (abfd);
2872 /* Function symbols do not count. */
2873 if (bed->is_function_type (ELF_ST_TYPE (sym->st_info)))
2874 return FALSE;
2875
2876 /* If the section is undefined, then so is the symbol. */
2877 if (sym->st_shndx == SHN_UNDEF)
2878 return FALSE;
2879
2880 /* If the symbol is defined in the common section, then
2881 it is a common definition and so does not count. */
2882 if (bed->common_definition (sym))
2883 return FALSE;
2884
2885 /* If the symbol is in a target specific section then we
2886 must rely upon the backend to tell us what it is. */
2887 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2888 /* FIXME - this function is not coded yet:
2889
2890 return _bfd_is_global_symbol_definition (abfd, sym);
2891
2892 Instead for now assume that the definition is not global,
2893 Even if this is wrong, at least the linker will behave
2894 in the same way that it used to do. */
2895 return FALSE;
2896
2897 return TRUE;
2898 }
2899
2900 /* Search the symbol table of the archive element of the archive ABFD
2901 whose archive map contains a mention of SYMDEF, and determine if
2902 the symbol is defined in this element. */
2903 static bfd_boolean
elf_link_is_defined_archive_symbol(bfd * abfd,carsym * symdef)2904 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2905 {
2906 Elf_Internal_Shdr * hdr;
2907 bfd_size_type symcount;
2908 bfd_size_type extsymcount;
2909 bfd_size_type extsymoff;
2910 Elf_Internal_Sym *isymbuf;
2911 Elf_Internal_Sym *isym;
2912 Elf_Internal_Sym *isymend;
2913 bfd_boolean result;
2914
2915 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2916 if (abfd == NULL)
2917 return FALSE;
2918
2919 if (! bfd_check_format (abfd, bfd_object))
2920 return FALSE;
2921
2922 /* If we have already included the element containing this symbol in the
2923 link then we do not need to include it again. Just claim that any symbol
2924 it contains is not a definition, so that our caller will not decide to
2925 (re)include this element. */
2926 if (abfd->archive_pass)
2927 return FALSE;
2928
2929 /* Select the appropriate symbol table. */
2930 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2931 hdr = &elf_tdata (abfd)->symtab_hdr;
2932 else
2933 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2934
2935 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2936
2937 /* The sh_info field of the symtab header tells us where the
2938 external symbols start. We don't care about the local symbols. */
2939 if (elf_bad_symtab (abfd))
2940 {
2941 extsymcount = symcount;
2942 extsymoff = 0;
2943 }
2944 else
2945 {
2946 extsymcount = symcount - hdr->sh_info;
2947 extsymoff = hdr->sh_info;
2948 }
2949
2950 if (extsymcount == 0)
2951 return FALSE;
2952
2953 /* Read in the symbol table. */
2954 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2955 NULL, NULL, NULL);
2956 if (isymbuf == NULL)
2957 return FALSE;
2958
2959 /* Scan the symbol table looking for SYMDEF. */
2960 result = FALSE;
2961 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2962 {
2963 const char *name;
2964
2965 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2966 isym->st_name);
2967 if (name == NULL)
2968 break;
2969
2970 if (strcmp (name, symdef->name) == 0)
2971 {
2972 result = is_global_data_symbol_definition (abfd, isym);
2973 break;
2974 }
2975 }
2976
2977 free (isymbuf);
2978
2979 return result;
2980 }
2981
2982 /* Add an entry to the .dynamic table. */
2983
2984 bfd_boolean
_bfd_elf_add_dynamic_entry(struct bfd_link_info * info,bfd_vma tag,bfd_vma val)2985 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2986 bfd_vma tag,
2987 bfd_vma val)
2988 {
2989 struct elf_link_hash_table *hash_table;
2990 const struct elf_backend_data *bed;
2991 asection *s;
2992 bfd_size_type newsize;
2993 bfd_byte *newcontents;
2994 Elf_Internal_Dyn dyn;
2995
2996 hash_table = elf_hash_table (info);
2997 if (! is_elf_hash_table (hash_table))
2998 return FALSE;
2999
3000 bed = get_elf_backend_data (hash_table->dynobj);
3001 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
3002 BFD_ASSERT (s != NULL);
3003
3004 newsize = s->size + bed->s->sizeof_dyn;
3005 newcontents = bfd_realloc (s->contents, newsize);
3006 if (newcontents == NULL)
3007 return FALSE;
3008
3009 dyn.d_tag = tag;
3010 dyn.d_un.d_val = val;
3011 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
3012
3013 s->size = newsize;
3014 s->contents = newcontents;
3015
3016 return TRUE;
3017 }
3018
3019 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
3020 otherwise just check whether one already exists. Returns -1 on error,
3021 1 if a DT_NEEDED tag already exists, and 0 on success. */
3022
3023 static int
elf_add_dt_needed_tag(bfd * abfd,struct bfd_link_info * info,const char * soname,bfd_boolean do_it)3024 elf_add_dt_needed_tag (bfd *abfd,
3025 struct bfd_link_info *info,
3026 const char *soname,
3027 bfd_boolean do_it)
3028 {
3029 struct elf_link_hash_table *hash_table;
3030 bfd_size_type oldsize;
3031 bfd_size_type strindex;
3032
3033 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
3034 return -1;
3035
3036 hash_table = elf_hash_table (info);
3037 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
3038 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
3039 if (strindex == (bfd_size_type) -1)
3040 return -1;
3041
3042 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
3043 {
3044 asection *sdyn;
3045 const struct elf_backend_data *bed;
3046 bfd_byte *extdyn;
3047
3048 bed = get_elf_backend_data (hash_table->dynobj);
3049 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
3050 if (sdyn != NULL)
3051 for (extdyn = sdyn->contents;
3052 extdyn < sdyn->contents + sdyn->size;
3053 extdyn += bed->s->sizeof_dyn)
3054 {
3055 Elf_Internal_Dyn dyn;
3056
3057 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3058 if (dyn.d_tag == DT_NEEDED
3059 && dyn.d_un.d_val == strindex)
3060 {
3061 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3062 return 1;
3063 }
3064 }
3065 }
3066
3067 if (do_it)
3068 {
3069 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
3070 return -1;
3071
3072 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
3073 return -1;
3074 }
3075 else
3076 /* We were just checking for existence of the tag. */
3077 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3078
3079 return 0;
3080 }
3081
3082 /* Sort symbol by value and section. */
3083 static int
elf_sort_symbol(const void * arg1,const void * arg2)3084 elf_sort_symbol (const void *arg1, const void *arg2)
3085 {
3086 const struct elf_link_hash_entry *h1;
3087 const struct elf_link_hash_entry *h2;
3088 bfd_signed_vma vdiff;
3089
3090 h1 = *(const struct elf_link_hash_entry **) arg1;
3091 h2 = *(const struct elf_link_hash_entry **) arg2;
3092 vdiff = h1->root.u.def.value - h2->root.u.def.value;
3093 if (vdiff != 0)
3094 return vdiff > 0 ? 1 : -1;
3095 else
3096 {
3097 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
3098 if (sdiff != 0)
3099 return sdiff > 0 ? 1 : -1;
3100 }
3101 return 0;
3102 }
3103
3104 /* This function is used to adjust offsets into .dynstr for
3105 dynamic symbols. This is called via elf_link_hash_traverse. */
3106
3107 static bfd_boolean
elf_adjust_dynstr_offsets(struct elf_link_hash_entry * h,void * data)3108 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3109 {
3110 struct elf_strtab_hash *dynstr = data;
3111
3112 if (h->root.type == bfd_link_hash_warning)
3113 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3114
3115 if (h->dynindx != -1)
3116 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3117 return TRUE;
3118 }
3119
3120 /* Assign string offsets in .dynstr, update all structures referencing
3121 them. */
3122
3123 static bfd_boolean
elf_finalize_dynstr(bfd * output_bfd,struct bfd_link_info * info)3124 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3125 {
3126 struct elf_link_hash_table *hash_table = elf_hash_table (info);
3127 struct elf_link_local_dynamic_entry *entry;
3128 struct elf_strtab_hash *dynstr = hash_table->dynstr;
3129 bfd *dynobj = hash_table->dynobj;
3130 asection *sdyn;
3131 bfd_size_type size;
3132 const struct elf_backend_data *bed;
3133 bfd_byte *extdyn;
3134
3135 _bfd_elf_strtab_finalize (dynstr);
3136 size = _bfd_elf_strtab_size (dynstr);
3137
3138 bed = get_elf_backend_data (dynobj);
3139 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3140 BFD_ASSERT (sdyn != NULL);
3141
3142 /* Update all .dynamic entries referencing .dynstr strings. */
3143 for (extdyn = sdyn->contents;
3144 extdyn < sdyn->contents + sdyn->size;
3145 extdyn += bed->s->sizeof_dyn)
3146 {
3147 Elf_Internal_Dyn dyn;
3148
3149 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3150 switch (dyn.d_tag)
3151 {
3152 case DT_STRSZ:
3153 dyn.d_un.d_val = size;
3154 break;
3155 case DT_NEEDED:
3156 case DT_SONAME:
3157 case DT_RPATH:
3158 case DT_RUNPATH:
3159 case DT_FILTER:
3160 case DT_AUXILIARY:
3161 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3162 break;
3163 default:
3164 continue;
3165 }
3166 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3167 }
3168
3169 /* Now update local dynamic symbols. */
3170 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3171 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3172 entry->isym.st_name);
3173
3174 /* And the rest of dynamic symbols. */
3175 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3176
3177 /* Adjust version definitions. */
3178 if (elf_tdata (output_bfd)->cverdefs)
3179 {
3180 asection *s;
3181 bfd_byte *p;
3182 bfd_size_type i;
3183 Elf_Internal_Verdef def;
3184 Elf_Internal_Verdaux defaux;
3185
3186 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3187 p = s->contents;
3188 do
3189 {
3190 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3191 &def);
3192 p += sizeof (Elf_External_Verdef);
3193 if (def.vd_aux != sizeof (Elf_External_Verdef))
3194 continue;
3195 for (i = 0; i < def.vd_cnt; ++i)
3196 {
3197 _bfd_elf_swap_verdaux_in (output_bfd,
3198 (Elf_External_Verdaux *) p, &defaux);
3199 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3200 defaux.vda_name);
3201 _bfd_elf_swap_verdaux_out (output_bfd,
3202 &defaux, (Elf_External_Verdaux *) p);
3203 p += sizeof (Elf_External_Verdaux);
3204 }
3205 }
3206 while (def.vd_next);
3207 }
3208
3209 /* Adjust version references. */
3210 if (elf_tdata (output_bfd)->verref)
3211 {
3212 asection *s;
3213 bfd_byte *p;
3214 bfd_size_type i;
3215 Elf_Internal_Verneed need;
3216 Elf_Internal_Vernaux needaux;
3217
3218 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3219 p = s->contents;
3220 do
3221 {
3222 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3223 &need);
3224 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3225 _bfd_elf_swap_verneed_out (output_bfd, &need,
3226 (Elf_External_Verneed *) p);
3227 p += sizeof (Elf_External_Verneed);
3228 for (i = 0; i < need.vn_cnt; ++i)
3229 {
3230 _bfd_elf_swap_vernaux_in (output_bfd,
3231 (Elf_External_Vernaux *) p, &needaux);
3232 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3233 needaux.vna_name);
3234 _bfd_elf_swap_vernaux_out (output_bfd,
3235 &needaux,
3236 (Elf_External_Vernaux *) p);
3237 p += sizeof (Elf_External_Vernaux);
3238 }
3239 }
3240 while (need.vn_next);
3241 }
3242
3243 return TRUE;
3244 }
3245
3246 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3247 The default is to only match when the INPUT and OUTPUT are exactly
3248 the same target. */
3249
3250 bfd_boolean
_bfd_elf_default_relocs_compatible(const bfd_target * input,const bfd_target * output)3251 _bfd_elf_default_relocs_compatible (const bfd_target *input,
3252 const bfd_target *output)
3253 {
3254 return input == output;
3255 }
3256
3257 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3258 This version is used when different targets for the same architecture
3259 are virtually identical. */
3260
3261 bfd_boolean
_bfd_elf_relocs_compatible(const bfd_target * input,const bfd_target * output)3262 _bfd_elf_relocs_compatible (const bfd_target *input,
3263 const bfd_target *output)
3264 {
3265 const struct elf_backend_data *obed, *ibed;
3266
3267 if (input == output)
3268 return TRUE;
3269
3270 ibed = xvec_get_elf_backend_data (input);
3271 obed = xvec_get_elf_backend_data (output);
3272
3273 if (ibed->arch != obed->arch)
3274 return FALSE;
3275
3276 /* If both backends are using this function, deem them compatible. */
3277 return ibed->relocs_compatible == obed->relocs_compatible;
3278 }
3279
3280 /* Add symbols from an ELF object file to the linker hash table. */
3281
3282 static bfd_boolean
elf_link_add_object_symbols(bfd * abfd,struct bfd_link_info * info)3283 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3284 {
3285 Elf_Internal_Shdr *hdr;
3286 bfd_size_type symcount;
3287 bfd_size_type extsymcount;
3288 bfd_size_type extsymoff;
3289 struct elf_link_hash_entry **sym_hash;
3290 bfd_boolean dynamic;
3291 Elf_External_Versym *extversym = NULL;
3292 Elf_External_Versym *ever;
3293 struct elf_link_hash_entry *weaks;
3294 struct elf_link_hash_entry **nondeflt_vers = NULL;
3295 bfd_size_type nondeflt_vers_cnt = 0;
3296 Elf_Internal_Sym *isymbuf = NULL;
3297 Elf_Internal_Sym *isym;
3298 Elf_Internal_Sym *isymend;
3299 const struct elf_backend_data *bed;
3300 bfd_boolean add_needed;
3301 struct elf_link_hash_table *htab;
3302 bfd_size_type amt;
3303 void *alloc_mark = NULL;
3304 struct bfd_hash_entry **old_table = NULL;
3305 unsigned int old_size = 0;
3306 unsigned int old_count = 0;
3307 void *old_tab = NULL;
3308 void *old_hash;
3309 void *old_ent;
3310 struct bfd_link_hash_entry *old_undefs = NULL;
3311 struct bfd_link_hash_entry *old_undefs_tail = NULL;
3312 long old_dynsymcount = 0;
3313 size_t tabsize = 0;
3314 size_t hashsize = 0;
3315
3316 htab = elf_hash_table (info);
3317 bed = get_elf_backend_data (abfd);
3318
3319 if ((abfd->flags & DYNAMIC) == 0)
3320 dynamic = FALSE;
3321 else
3322 {
3323 dynamic = TRUE;
3324
3325 /* You can't use -r against a dynamic object. Also, there's no
3326 hope of using a dynamic object which does not exactly match
3327 the format of the output file. */
3328 if (info->relocatable
3329 || !is_elf_hash_table (htab)
3330 || htab->root.creator != abfd->xvec)
3331 {
3332 if (info->relocatable)
3333 bfd_set_error (bfd_error_invalid_operation);
3334 else
3335 bfd_set_error (bfd_error_wrong_format);
3336 goto error_return;
3337 }
3338 }
3339
3340 /* As a GNU extension, any input sections which are named
3341 .gnu.warning.SYMBOL are treated as warning symbols for the given
3342 symbol. This differs from .gnu.warning sections, which generate
3343 warnings when they are included in an output file. */
3344 if (info->executable)
3345 {
3346 asection *s;
3347
3348 for (s = abfd->sections; s != NULL; s = s->next)
3349 {
3350 const char *name;
3351
3352 name = bfd_get_section_name (abfd, s);
3353 if (CONST_STRNEQ (name, ".gnu.warning."))
3354 {
3355 char *msg;
3356 bfd_size_type sz;
3357
3358 name += sizeof ".gnu.warning." - 1;
3359
3360 /* If this is a shared object, then look up the symbol
3361 in the hash table. If it is there, and it is already
3362 been defined, then we will not be using the entry
3363 from this shared object, so we don't need to warn.
3364 FIXME: If we see the definition in a regular object
3365 later on, we will warn, but we shouldn't. The only
3366 fix is to keep track of what warnings we are supposed
3367 to emit, and then handle them all at the end of the
3368 link. */
3369 if (dynamic)
3370 {
3371 struct elf_link_hash_entry *h;
3372
3373 h = elf_link_hash_lookup (htab, name, FALSE, FALSE, TRUE);
3374
3375 /* FIXME: What about bfd_link_hash_common? */
3376 if (h != NULL
3377 && (h->root.type == bfd_link_hash_defined
3378 || h->root.type == bfd_link_hash_defweak))
3379 {
3380 /* We don't want to issue this warning. Clobber
3381 the section size so that the warning does not
3382 get copied into the output file. */
3383 s->size = 0;
3384 continue;
3385 }
3386 }
3387
3388 sz = s->size;
3389 msg = bfd_alloc (abfd, sz + 1);
3390 if (msg == NULL)
3391 goto error_return;
3392
3393 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3394 goto error_return;
3395
3396 msg[sz] = '\0';
3397
3398 if (! (_bfd_generic_link_add_one_symbol
3399 (info, abfd, name, BSF_WARNING, s, 0, msg,
3400 FALSE, bed->collect, NULL)))
3401 goto error_return;
3402
3403 if (! info->relocatable)
3404 {
3405 /* Clobber the section size so that the warning does
3406 not get copied into the output file. */
3407 s->size = 0;
3408
3409 /* Also set SEC_EXCLUDE, so that symbols defined in
3410 the warning section don't get copied to the output. */
3411 s->flags |= SEC_EXCLUDE;
3412 }
3413 }
3414 }
3415 }
3416
3417 add_needed = TRUE;
3418 if (! dynamic)
3419 {
3420 /* If we are creating a shared library, create all the dynamic
3421 sections immediately. We need to attach them to something,
3422 so we attach them to this BFD, provided it is the right
3423 format. FIXME: If there are no input BFD's of the same
3424 format as the output, we can't make a shared library. */
3425 if (info->shared
3426 && is_elf_hash_table (htab)
3427 && htab->root.creator == abfd->xvec
3428 && !htab->dynamic_sections_created)
3429 {
3430 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3431 goto error_return;
3432 }
3433 }
3434 else if (!is_elf_hash_table (htab))
3435 goto error_return;
3436 else
3437 {
3438 asection *s;
3439 const char *soname = NULL;
3440 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3441 int ret;
3442
3443 /* ld --just-symbols and dynamic objects don't mix very well.
3444 ld shouldn't allow it. */
3445 if ((s = abfd->sections) != NULL
3446 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3447 abort ();
3448
3449 /* If this dynamic lib was specified on the command line with
3450 --as-needed in effect, then we don't want to add a DT_NEEDED
3451 tag unless the lib is actually used. Similary for libs brought
3452 in by another lib's DT_NEEDED. When --no-add-needed is used
3453 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3454 any dynamic library in DT_NEEDED tags in the dynamic lib at
3455 all. */
3456 add_needed = (elf_dyn_lib_class (abfd)
3457 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3458 | DYN_NO_NEEDED)) == 0;
3459
3460 s = bfd_get_section_by_name (abfd, ".dynamic");
3461 if (s != NULL)
3462 {
3463 bfd_byte *dynbuf;
3464 bfd_byte *extdyn;
3465 int elfsec;
3466 unsigned long shlink;
3467
3468 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3469 goto error_free_dyn;
3470
3471 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3472 if (elfsec == -1)
3473 goto error_free_dyn;
3474 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3475
3476 for (extdyn = dynbuf;
3477 extdyn < dynbuf + s->size;
3478 extdyn += bed->s->sizeof_dyn)
3479 {
3480 Elf_Internal_Dyn dyn;
3481
3482 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3483 if (dyn.d_tag == DT_SONAME)
3484 {
3485 unsigned int tagv = dyn.d_un.d_val;
3486 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3487 if (soname == NULL)
3488 goto error_free_dyn;
3489 }
3490 if (dyn.d_tag == DT_NEEDED)
3491 {
3492 struct bfd_link_needed_list *n, **pn;
3493 char *fnm, *anm;
3494 unsigned int tagv = dyn.d_un.d_val;
3495
3496 amt = sizeof (struct bfd_link_needed_list);
3497 n = bfd_alloc (abfd, amt);
3498 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3499 if (n == NULL || fnm == NULL)
3500 goto error_free_dyn;
3501 amt = strlen (fnm) + 1;
3502 anm = bfd_alloc (abfd, amt);
3503 if (anm == NULL)
3504 goto error_free_dyn;
3505 memcpy (anm, fnm, amt);
3506 n->name = anm;
3507 n->by = abfd;
3508 n->next = NULL;
3509 for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
3510 ;
3511 *pn = n;
3512 }
3513 if (dyn.d_tag == DT_RUNPATH)
3514 {
3515 struct bfd_link_needed_list *n, **pn;
3516 char *fnm, *anm;
3517 unsigned int tagv = dyn.d_un.d_val;
3518
3519 amt = sizeof (struct bfd_link_needed_list);
3520 n = bfd_alloc (abfd, amt);
3521 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3522 if (n == NULL || fnm == NULL)
3523 goto error_free_dyn;
3524 amt = strlen (fnm) + 1;
3525 anm = bfd_alloc (abfd, amt);
3526 if (anm == NULL)
3527 goto error_free_dyn;
3528 memcpy (anm, fnm, amt);
3529 n->name = anm;
3530 n->by = abfd;
3531 n->next = NULL;
3532 for (pn = & runpath;
3533 *pn != NULL;
3534 pn = &(*pn)->next)
3535 ;
3536 *pn = n;
3537 }
3538 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3539 if (!runpath && dyn.d_tag == DT_RPATH)
3540 {
3541 struct bfd_link_needed_list *n, **pn;
3542 char *fnm, *anm;
3543 unsigned int tagv = dyn.d_un.d_val;
3544
3545 amt = sizeof (struct bfd_link_needed_list);
3546 n = bfd_alloc (abfd, amt);
3547 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3548 if (n == NULL || fnm == NULL)
3549 goto error_free_dyn;
3550 amt = strlen (fnm) + 1;
3551 anm = bfd_alloc (abfd, amt);
3552 if (anm == NULL)
3553 {
3554 error_free_dyn:
3555 free (dynbuf);
3556 goto error_return;
3557 }
3558 memcpy (anm, fnm, amt);
3559 n->name = anm;
3560 n->by = abfd;
3561 n->next = NULL;
3562 for (pn = & rpath;
3563 *pn != NULL;
3564 pn = &(*pn)->next)
3565 ;
3566 *pn = n;
3567 }
3568 }
3569
3570 free (dynbuf);
3571 }
3572
3573 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3574 frees all more recently bfd_alloc'd blocks as well. */
3575 if (runpath)
3576 rpath = runpath;
3577
3578 if (rpath)
3579 {
3580 struct bfd_link_needed_list **pn;
3581 for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
3582 ;
3583 *pn = rpath;
3584 }
3585
3586 /* We do not want to include any of the sections in a dynamic
3587 object in the output file. We hack by simply clobbering the
3588 list of sections in the BFD. This could be handled more
3589 cleanly by, say, a new section flag; the existing
3590 SEC_NEVER_LOAD flag is not the one we want, because that one
3591 still implies that the section takes up space in the output
3592 file. */
3593 bfd_section_list_clear (abfd);
3594
3595 /* Find the name to use in a DT_NEEDED entry that refers to this
3596 object. If the object has a DT_SONAME entry, we use it.
3597 Otherwise, if the generic linker stuck something in
3598 elf_dt_name, we use that. Otherwise, we just use the file
3599 name. */
3600 if (soname == NULL || *soname == '\0')
3601 {
3602 soname = elf_dt_name (abfd);
3603 if (soname == NULL || *soname == '\0')
3604 soname = bfd_get_filename (abfd);
3605 }
3606
3607 /* Save the SONAME because sometimes the linker emulation code
3608 will need to know it. */
3609 elf_dt_name (abfd) = soname;
3610
3611 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3612 if (ret < 0)
3613 goto error_return;
3614
3615 /* If we have already included this dynamic object in the
3616 link, just ignore it. There is no reason to include a
3617 particular dynamic object more than once. */
3618 if (ret > 0)
3619 return TRUE;
3620 }
3621
3622 /* If this is a dynamic object, we always link against the .dynsym
3623 symbol table, not the .symtab symbol table. The dynamic linker
3624 will only see the .dynsym symbol table, so there is no reason to
3625 look at .symtab for a dynamic object. */
3626
3627 if (! dynamic || elf_dynsymtab (abfd) == 0)
3628 hdr = &elf_tdata (abfd)->symtab_hdr;
3629 else
3630 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3631
3632 symcount = hdr->sh_size / bed->s->sizeof_sym;
3633
3634 /* The sh_info field of the symtab header tells us where the
3635 external symbols start. We don't care about the local symbols at
3636 this point. */
3637 if (elf_bad_symtab (abfd))
3638 {
3639 extsymcount = symcount;
3640 extsymoff = 0;
3641 }
3642 else
3643 {
3644 extsymcount = symcount - hdr->sh_info;
3645 extsymoff = hdr->sh_info;
3646 }
3647
3648 sym_hash = NULL;
3649 if (extsymcount != 0)
3650 {
3651 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3652 NULL, NULL, NULL);
3653 if (isymbuf == NULL)
3654 goto error_return;
3655
3656 /* We store a pointer to the hash table entry for each external
3657 symbol. */
3658 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3659 sym_hash = bfd_alloc (abfd, amt);
3660 if (sym_hash == NULL)
3661 goto error_free_sym;
3662 elf_sym_hashes (abfd) = sym_hash;
3663 }
3664
3665 if (dynamic)
3666 {
3667 /* Read in any version definitions. */
3668 if (!_bfd_elf_slurp_version_tables (abfd,
3669 info->default_imported_symver))
3670 goto error_free_sym;
3671
3672 /* Read in the symbol versions, but don't bother to convert them
3673 to internal format. */
3674 if (elf_dynversym (abfd) != 0)
3675 {
3676 Elf_Internal_Shdr *versymhdr;
3677
3678 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3679 extversym = bfd_malloc (versymhdr->sh_size);
3680 if (extversym == NULL)
3681 goto error_free_sym;
3682 amt = versymhdr->sh_size;
3683 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3684 || bfd_bread (extversym, amt, abfd) != amt)
3685 goto error_free_vers;
3686 }
3687 }
3688
3689 /* If we are loading an as-needed shared lib, save the symbol table
3690 state before we start adding symbols. If the lib turns out
3691 to be unneeded, restore the state. */
3692 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
3693 {
3694 unsigned int i;
3695 size_t entsize;
3696
3697 for (entsize = 0, i = 0; i < htab->root.table.size; i++)
3698 {
3699 struct bfd_hash_entry *p;
3700 struct elf_link_hash_entry *h;
3701
3702 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3703 {
3704 h = (struct elf_link_hash_entry *) p;
3705 entsize += htab->root.table.entsize;
3706 if (h->root.type == bfd_link_hash_warning)
3707 entsize += htab->root.table.entsize;
3708 }
3709 }
3710
3711 tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
3712 hashsize = extsymcount * sizeof (struct elf_link_hash_entry *);
3713 old_tab = bfd_malloc (tabsize + entsize + hashsize);
3714 if (old_tab == NULL)
3715 goto error_free_vers;
3716
3717 /* Remember the current objalloc pointer, so that all mem for
3718 symbols added can later be reclaimed. */
3719 alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
3720 if (alloc_mark == NULL)
3721 goto error_free_vers;
3722
3723 /* Make a special call to the linker "notice" function to
3724 tell it that we are about to handle an as-needed lib. */
3725 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
3726 notice_as_needed))
3727 return FALSE;
3728
3729
3730 /* Clone the symbol table and sym hashes. Remember some
3731 pointers into the symbol table, and dynamic symbol count. */
3732 old_hash = (char *) old_tab + tabsize;
3733 old_ent = (char *) old_hash + hashsize;
3734 memcpy (old_tab, htab->root.table.table, tabsize);
3735 memcpy (old_hash, sym_hash, hashsize);
3736 old_undefs = htab->root.undefs;
3737 old_undefs_tail = htab->root.undefs_tail;
3738 old_table = htab->root.table.table;
3739 old_size = htab->root.table.size;
3740 old_count = htab->root.table.count;
3741 old_dynsymcount = htab->dynsymcount;
3742
3743 for (i = 0; i < htab->root.table.size; i++)
3744 {
3745 struct bfd_hash_entry *p;
3746 struct elf_link_hash_entry *h;
3747
3748 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3749 {
3750 memcpy (old_ent, p, htab->root.table.entsize);
3751 old_ent = (char *) old_ent + htab->root.table.entsize;
3752 h = (struct elf_link_hash_entry *) p;
3753 if (h->root.type == bfd_link_hash_warning)
3754 {
3755 memcpy (old_ent, h->root.u.i.link, htab->root.table.entsize);
3756 old_ent = (char *) old_ent + htab->root.table.entsize;
3757 }
3758 }
3759 }
3760 }
3761
3762 weaks = NULL;
3763 ever = extversym != NULL ? extversym + extsymoff : NULL;
3764 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3765 isym < isymend;
3766 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3767 {
3768 int bind;
3769 bfd_vma value;
3770 asection *sec, *new_sec;
3771 flagword flags;
3772 const char *name;
3773 struct elf_link_hash_entry *h;
3774 bfd_boolean definition;
3775 bfd_boolean size_change_ok;
3776 bfd_boolean type_change_ok;
3777 bfd_boolean new_weakdef;
3778 bfd_boolean override;
3779 bfd_boolean common;
3780 unsigned int old_alignment;
3781 bfd *old_bfd;
3782
3783 override = FALSE;
3784
3785 flags = BSF_NO_FLAGS;
3786 sec = NULL;
3787 value = isym->st_value;
3788 *sym_hash = NULL;
3789 common = bed->common_definition (isym);
3790
3791 bind = ELF_ST_BIND (isym->st_info);
3792 if (bind == STB_LOCAL)
3793 {
3794 /* This should be impossible, since ELF requires that all
3795 global symbols follow all local symbols, and that sh_info
3796 point to the first global symbol. Unfortunately, Irix 5
3797 screws this up. */
3798 continue;
3799 }
3800 else if (bind == STB_GLOBAL)
3801 {
3802 if (isym->st_shndx != SHN_UNDEF && !common)
3803 flags = BSF_GLOBAL;
3804 }
3805 else if (bind == STB_WEAK)
3806 flags = BSF_WEAK;
3807 else
3808 {
3809 /* Leave it up to the processor backend. */
3810 }
3811
3812 if (isym->st_shndx == SHN_UNDEF)
3813 sec = bfd_und_section_ptr;
3814 else if (isym->st_shndx < SHN_LORESERVE
3815 || isym->st_shndx > SHN_HIRESERVE)
3816 {
3817 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3818 if (sec == NULL)
3819 sec = bfd_abs_section_ptr;
3820 else if (sec->kept_section)
3821 {
3822 /* Symbols from discarded section are undefined. We keep
3823 its visibility. */
3824 sec = bfd_und_section_ptr;
3825 isym->st_shndx = SHN_UNDEF;
3826 }
3827 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3828 value -= sec->vma;
3829 }
3830 else if (isym->st_shndx == SHN_ABS)
3831 sec = bfd_abs_section_ptr;
3832 else if (isym->st_shndx == SHN_COMMON)
3833 {
3834 sec = bfd_com_section_ptr;
3835 /* What ELF calls the size we call the value. What ELF
3836 calls the value we call the alignment. */
3837 value = isym->st_size;
3838 }
3839 else
3840 {
3841 /* Leave it up to the processor backend. */
3842 }
3843
3844 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3845 isym->st_name);
3846 if (name == NULL)
3847 goto error_free_vers;
3848
3849 if (isym->st_shndx == SHN_COMMON
3850 && ELF_ST_TYPE (isym->st_info) == STT_TLS
3851 && !info->relocatable)
3852 {
3853 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3854
3855 if (tcomm == NULL)
3856 {
3857 tcomm = bfd_make_section_with_flags (abfd, ".tcommon",
3858 (SEC_ALLOC
3859 | SEC_IS_COMMON
3860 | SEC_LINKER_CREATED
3861 | SEC_THREAD_LOCAL));
3862 if (tcomm == NULL)
3863 goto error_free_vers;
3864 }
3865 sec = tcomm;
3866 }
3867 else if (bed->elf_add_symbol_hook)
3868 {
3869 if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
3870 &sec, &value))
3871 goto error_free_vers;
3872
3873 /* The hook function sets the name to NULL if this symbol
3874 should be skipped for some reason. */
3875 if (name == NULL)
3876 continue;
3877 }
3878
3879 /* Sanity check that all possibilities were handled. */
3880 if (sec == NULL)
3881 {
3882 bfd_set_error (bfd_error_bad_value);
3883 goto error_free_vers;
3884 }
3885
3886 if (bfd_is_und_section (sec)
3887 || bfd_is_com_section (sec))
3888 definition = FALSE;
3889 else
3890 definition = TRUE;
3891
3892 size_change_ok = FALSE;
3893 type_change_ok = bed->type_change_ok;
3894 old_alignment = 0;
3895 old_bfd = NULL;
3896 new_sec = sec;
3897
3898 if (is_elf_hash_table (htab))
3899 {
3900 Elf_Internal_Versym iver;
3901 unsigned int vernum = 0;
3902 bfd_boolean skip;
3903
3904 if (ever == NULL)
3905 {
3906 if (info->default_imported_symver)
3907 /* Use the default symbol version created earlier. */
3908 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3909 else
3910 iver.vs_vers = 0;
3911 }
3912 else
3913 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3914
3915 vernum = iver.vs_vers & VERSYM_VERSION;
3916
3917 /* If this is a hidden symbol, or if it is not version
3918 1, we append the version name to the symbol name.
3919 However, we do not modify a non-hidden absolute symbol
3920 if it is not a function, because it might be the version
3921 symbol itself. FIXME: What if it isn't? */
3922 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3923 || (vernum > 1
3924 && (!bfd_is_abs_section (sec)
3925 || bed->is_function_type (ELF_ST_TYPE (isym->st_info)))))
3926 {
3927 const char *verstr;
3928 size_t namelen, verlen, newlen;
3929 char *newname, *p;
3930
3931 if (isym->st_shndx != SHN_UNDEF)
3932 {
3933 if (vernum > elf_tdata (abfd)->cverdefs)
3934 verstr = NULL;
3935 else if (vernum > 1)
3936 verstr =
3937 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3938 else
3939 verstr = "";
3940
3941 if (verstr == NULL)
3942 {
3943 (*_bfd_error_handler)
3944 (_("%B: %s: invalid version %u (max %d)"),
3945 abfd, name, vernum,
3946 elf_tdata (abfd)->cverdefs);
3947 bfd_set_error (bfd_error_bad_value);
3948 goto error_free_vers;
3949 }
3950 }
3951 else
3952 {
3953 /* We cannot simply test for the number of
3954 entries in the VERNEED section since the
3955 numbers for the needed versions do not start
3956 at 0. */
3957 Elf_Internal_Verneed *t;
3958
3959 verstr = NULL;
3960 for (t = elf_tdata (abfd)->verref;
3961 t != NULL;
3962 t = t->vn_nextref)
3963 {
3964 Elf_Internal_Vernaux *a;
3965
3966 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3967 {
3968 if (a->vna_other == vernum)
3969 {
3970 verstr = a->vna_nodename;
3971 break;
3972 }
3973 }
3974 if (a != NULL)
3975 break;
3976 }
3977 if (verstr == NULL)
3978 {
3979 (*_bfd_error_handler)
3980 (_("%B: %s: invalid needed version %d"),
3981 abfd, name, vernum);
3982 bfd_set_error (bfd_error_bad_value);
3983 goto error_free_vers;
3984 }
3985 }
3986
3987 namelen = strlen (name);
3988 verlen = strlen (verstr);
3989 newlen = namelen + verlen + 2;
3990 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3991 && isym->st_shndx != SHN_UNDEF)
3992 ++newlen;
3993
3994 newname = bfd_hash_allocate (&htab->root.table, newlen);
3995 if (newname == NULL)
3996 goto error_free_vers;
3997 memcpy (newname, name, namelen);
3998 p = newname + namelen;
3999 *p++ = ELF_VER_CHR;
4000 /* If this is a defined non-hidden version symbol,
4001 we add another @ to the name. This indicates the
4002 default version of the symbol. */
4003 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
4004 && isym->st_shndx != SHN_UNDEF)
4005 *p++ = ELF_VER_CHR;
4006 memcpy (p, verstr, verlen + 1);
4007
4008 name = newname;
4009 }
4010
4011 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
4012 &value, &old_alignment,
4013 sym_hash, &skip, &override,
4014 &type_change_ok, &size_change_ok))
4015 goto error_free_vers;
4016
4017 if (skip)
4018 continue;
4019
4020 if (override)
4021 definition = FALSE;
4022
4023 h = *sym_hash;
4024 while (h->root.type == bfd_link_hash_indirect
4025 || h->root.type == bfd_link_hash_warning)
4026 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4027
4028 /* Remember the old alignment if this is a common symbol, so
4029 that we don't reduce the alignment later on. We can't
4030 check later, because _bfd_generic_link_add_one_symbol
4031 will set a default for the alignment which we want to
4032 override. We also remember the old bfd where the existing
4033 definition comes from. */
4034 switch (h->root.type)
4035 {
4036 default:
4037 break;
4038
4039 case bfd_link_hash_defined:
4040 case bfd_link_hash_defweak:
4041 old_bfd = h->root.u.def.section->owner;
4042 break;
4043
4044 case bfd_link_hash_common:
4045 old_bfd = h->root.u.c.p->section->owner;
4046 old_alignment = h->root.u.c.p->alignment_power;
4047 break;
4048 }
4049
4050 if (elf_tdata (abfd)->verdef != NULL
4051 && ! override
4052 && vernum > 1
4053 && definition)
4054 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
4055 }
4056
4057 if (! (_bfd_generic_link_add_one_symbol
4058 (info, abfd, name, flags, sec, value, NULL, FALSE, bed->collect,
4059 (struct bfd_link_hash_entry **) sym_hash)))
4060 goto error_free_vers;
4061
4062 h = *sym_hash;
4063 while (h->root.type == bfd_link_hash_indirect
4064 || h->root.type == bfd_link_hash_warning)
4065 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4066 *sym_hash = h;
4067
4068 new_weakdef = FALSE;
4069 if (dynamic
4070 && definition
4071 && (flags & BSF_WEAK) != 0
4072 && !bed->is_function_type (ELF_ST_TYPE (isym->st_info))
4073 && is_elf_hash_table (htab)
4074 && h->u.weakdef == NULL)
4075 {
4076 /* Keep a list of all weak defined non function symbols from
4077 a dynamic object, using the weakdef field. Later in this
4078 function we will set the weakdef field to the correct
4079 value. We only put non-function symbols from dynamic
4080 objects on this list, because that happens to be the only
4081 time we need to know the normal symbol corresponding to a
4082 weak symbol, and the information is time consuming to
4083 figure out. If the weakdef field is not already NULL,
4084 then this symbol was already defined by some previous
4085 dynamic object, and we will be using that previous
4086 definition anyhow. */
4087
4088 h->u.weakdef = weaks;
4089 weaks = h;
4090 new_weakdef = TRUE;
4091 }
4092
4093 /* Set the alignment of a common symbol. */
4094 if ((common || bfd_is_com_section (sec))
4095 && h->root.type == bfd_link_hash_common)
4096 {
4097 unsigned int align;
4098
4099 if (common)
4100 align = bfd_log2 (isym->st_value);
4101 else
4102 {
4103 /* The new symbol is a common symbol in a shared object.
4104 We need to get the alignment from the section. */
4105 align = new_sec->alignment_power;
4106 }
4107 if (align > old_alignment
4108 /* Permit an alignment power of zero if an alignment of one
4109 is specified and no other alignments have been specified. */
4110 || (isym->st_value == 1 && old_alignment == 0))
4111 h->root.u.c.p->alignment_power = align;
4112 else
4113 h->root.u.c.p->alignment_power = old_alignment;
4114 }
4115
4116 if (is_elf_hash_table (htab))
4117 {
4118 bfd_boolean dynsym;
4119
4120 /* Check the alignment when a common symbol is involved. This
4121 can change when a common symbol is overridden by a normal
4122 definition or a common symbol is ignored due to the old
4123 normal definition. We need to make sure the maximum
4124 alignment is maintained. */
4125 if ((old_alignment || common)
4126 && h->root.type != bfd_link_hash_common)
4127 {
4128 unsigned int common_align;
4129 unsigned int normal_align;
4130 unsigned int symbol_align;
4131 bfd *normal_bfd;
4132 bfd *common_bfd;
4133
4134 symbol_align = ffs (h->root.u.def.value) - 1;
4135 if (h->root.u.def.section->owner != NULL
4136 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
4137 {
4138 normal_align = h->root.u.def.section->alignment_power;
4139 if (normal_align > symbol_align)
4140 normal_align = symbol_align;
4141 }
4142 else
4143 normal_align = symbol_align;
4144
4145 if (old_alignment)
4146 {
4147 common_align = old_alignment;
4148 common_bfd = old_bfd;
4149 normal_bfd = abfd;
4150 }
4151 else
4152 {
4153 common_align = bfd_log2 (isym->st_value);
4154 common_bfd = abfd;
4155 normal_bfd = old_bfd;
4156 }
4157
4158 if (normal_align < common_align)
4159 {
4160 /* PR binutils/2735 */
4161 if (normal_bfd == NULL)
4162 (*_bfd_error_handler)
4163 (_("Warning: alignment %u of common symbol `%s' in %B"
4164 " is greater than the alignment (%u) of its section %A"),
4165 common_bfd, h->root.u.def.section,
4166 1 << common_align, name, 1 << normal_align);
4167 else
4168 (*_bfd_error_handler)
4169 (_("Warning: alignment %u of symbol `%s' in %B"
4170 " is smaller than %u in %B"),
4171 normal_bfd, common_bfd,
4172 1 << normal_align, name, 1 << common_align);
4173 }
4174 }
4175
4176 /* Remember the symbol size if it isn't undefined. */
4177 if ((isym->st_size != 0 && isym->st_shndx != SHN_UNDEF)
4178 && (definition || h->size == 0))
4179 {
4180 if (h->size != 0
4181 && h->size != isym->st_size
4182 && ! size_change_ok)
4183 (*_bfd_error_handler)
4184 (_("Warning: size of symbol `%s' changed"
4185 " from %lu in %B to %lu in %B"),
4186 old_bfd, abfd,
4187 name, (unsigned long) h->size,
4188 (unsigned long) isym->st_size);
4189
4190 h->size = isym->st_size;
4191 }
4192
4193 /* If this is a common symbol, then we always want H->SIZE
4194 to be the size of the common symbol. The code just above
4195 won't fix the size if a common symbol becomes larger. We
4196 don't warn about a size change here, because that is
4197 covered by --warn-common. Allow changed between different
4198 function types. */
4199 if (h->root.type == bfd_link_hash_common)
4200 h->size = h->root.u.c.size;
4201
4202 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
4203 && (definition || h->type == STT_NOTYPE))
4204 {
4205 if (h->type != STT_NOTYPE
4206 && h->type != ELF_ST_TYPE (isym->st_info)
4207 && ! type_change_ok)
4208 (*_bfd_error_handler)
4209 (_("Warning: type of symbol `%s' changed"
4210 " from %d to %d in %B"),
4211 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
4212
4213 h->type = ELF_ST_TYPE (isym->st_info);
4214 }
4215
4216 /* If st_other has a processor-specific meaning, specific
4217 code might be needed here. We never merge the visibility
4218 attribute with the one from a dynamic object. */
4219 if (bed->elf_backend_merge_symbol_attribute)
4220 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
4221 dynamic);
4222
4223 /* If this symbol has default visibility and the user has requested
4224 we not re-export it, then mark it as hidden. */
4225 if (definition && !dynamic
4226 && (abfd->no_export
4227 || (abfd->my_archive && abfd->my_archive->no_export))
4228 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
4229 isym->st_other = (STV_HIDDEN
4230 | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
4231
4232 if (ELF_ST_VISIBILITY (isym->st_other) != 0 && !dynamic)
4233 {
4234 unsigned char hvis, symvis, other, nvis;
4235
4236 /* Only merge the visibility. Leave the remainder of the
4237 st_other field to elf_backend_merge_symbol_attribute. */
4238 other = h->other & ~ELF_ST_VISIBILITY (-1);
4239
4240 /* Combine visibilities, using the most constraining one. */
4241 hvis = ELF_ST_VISIBILITY (h->other);
4242 symvis = ELF_ST_VISIBILITY (isym->st_other);
4243 if (! hvis)
4244 nvis = symvis;
4245 else if (! symvis)
4246 nvis = hvis;
4247 else
4248 nvis = hvis < symvis ? hvis : symvis;
4249
4250 h->other = other | nvis;
4251 }
4252
4253 /* Set a flag in the hash table entry indicating the type of
4254 reference or definition we just found. Keep a count of
4255 the number of dynamic symbols we find. A dynamic symbol
4256 is one which is referenced or defined by both a regular
4257 object and a shared object. */
4258 dynsym = FALSE;
4259 if (! dynamic)
4260 {
4261 if (! definition)
4262 {
4263 h->ref_regular = 1;
4264 if (bind != STB_WEAK)
4265 h->ref_regular_nonweak = 1;
4266 }
4267 else
4268 h->def_regular = 1;
4269 if (! info->executable
4270 || h->def_dynamic
4271 || h->ref_dynamic)
4272 dynsym = TRUE;
4273 }
4274 else
4275 {
4276 if (! definition)
4277 h->ref_dynamic = 1;
4278 else
4279 h->def_dynamic = 1;
4280 if (h->def_regular
4281 || h->ref_regular
4282 || (h->u.weakdef != NULL
4283 && ! new_weakdef
4284 && h->u.weakdef->dynindx != -1))
4285 dynsym = TRUE;
4286 }
4287
4288 if (definition && (sec->flags & SEC_DEBUGGING))
4289 {
4290 /* We don't want to make debug symbol dynamic. */
4291 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4292 dynsym = FALSE;
4293 }
4294
4295 /* Check to see if we need to add an indirect symbol for
4296 the default name. */
4297 if (definition || h->root.type == bfd_link_hash_common)
4298 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4299 &sec, &value, &dynsym,
4300 override))
4301 goto error_free_vers;
4302
4303 if (definition && !dynamic)
4304 {
4305 char *p = strchr (name, ELF_VER_CHR);
4306 if (p != NULL && p[1] != ELF_VER_CHR)
4307 {
4308 /* Queue non-default versions so that .symver x, x@FOO
4309 aliases can be checked. */
4310 if (!nondeflt_vers)
4311 {
4312 amt = ((isymend - isym + 1)
4313 * sizeof (struct elf_link_hash_entry *));
4314 nondeflt_vers = bfd_malloc (amt);
4315 }
4316 nondeflt_vers[nondeflt_vers_cnt++] = h;
4317 }
4318 }
4319
4320 if (dynsym && h->dynindx == -1)
4321 {
4322 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4323 goto error_free_vers;
4324 if (h->u.weakdef != NULL
4325 && ! new_weakdef
4326 && h->u.weakdef->dynindx == -1)
4327 {
4328 if (!bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4329 goto error_free_vers;
4330 }
4331 }
4332 else if (dynsym && h->dynindx != -1)
4333 /* If the symbol already has a dynamic index, but
4334 visibility says it should not be visible, turn it into
4335 a local symbol. */
4336 switch (ELF_ST_VISIBILITY (h->other))
4337 {
4338 case STV_INTERNAL:
4339 case STV_HIDDEN:
4340 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4341 dynsym = FALSE;
4342 break;
4343 }
4344
4345 if (!add_needed
4346 && definition
4347 && dynsym
4348 && h->ref_regular)
4349 {
4350 int ret;
4351 const char *soname = elf_dt_name (abfd);
4352
4353 /* A symbol from a library loaded via DT_NEEDED of some
4354 other library is referenced by a regular object.
4355 Add a DT_NEEDED entry for it. Issue an error if
4356 --no-add-needed is used. */
4357 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4358 {
4359 bfd_boolean looks_soish;
4360 const char *print_name;
4361 int print_len;
4362 size_t len, lend = 0;
4363
4364 looks_soish = FALSE;
4365 print_name = soname;
4366 print_len = strlen(soname);
4367 if (strncmp(soname, "lib", 3) == 0)
4368 {
4369 len = print_len;
4370 if (len > 5 && strcmp(soname + len - 2, ".a") == 0)
4371 lend = len - 5;
4372 else
4373 {
4374 while (len > 6 && (ISDIGIT(soname[len - 1]) ||
4375 soname[len - 1] == '.'))
4376 len--;
4377 if (strncmp(soname + len - 3, ".so", 3) == 0)
4378 lend = len - 6;
4379 }
4380 if (lend != 0)
4381 {
4382 print_name = soname + 3;
4383 print_len = lend;
4384 looks_soish = TRUE;
4385 }
4386 }
4387
4388 (*_bfd_error_handler)
4389 (_("undefined reference to symbol `%s' (try adding -l%s%.*s)"),
4390 name, looks_soish? "" : ":", print_len, print_name);
4391 bfd_set_error (bfd_error_bad_value);
4392 goto error_free_vers;
4393 }
4394
4395 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4396
4397 add_needed = TRUE;
4398 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4399 if (ret < 0)
4400 goto error_free_vers;
4401
4402 BFD_ASSERT (ret == 0);
4403 }
4404 }
4405 }
4406
4407 if (extversym != NULL)
4408 {
4409 free (extversym);
4410 extversym = NULL;
4411 }
4412
4413 if (isymbuf != NULL)
4414 {
4415 free (isymbuf);
4416 isymbuf = NULL;
4417 }
4418
4419 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4420 {
4421 unsigned int i;
4422
4423 /* Restore the symbol table. */
4424 if (bed->as_needed_cleanup)
4425 (*bed->as_needed_cleanup) (abfd, info);
4426 old_hash = (char *) old_tab + tabsize;
4427 old_ent = (char *) old_hash + hashsize;
4428 sym_hash = elf_sym_hashes (abfd);
4429 htab->root.table.table = old_table;
4430 htab->root.table.size = old_size;
4431 htab->root.table.count = old_count;
4432 memcpy (htab->root.table.table, old_tab, tabsize);
4433 memcpy (sym_hash, old_hash, hashsize);
4434 htab->root.undefs = old_undefs;
4435 htab->root.undefs_tail = old_undefs_tail;
4436 for (i = 0; i < htab->root.table.size; i++)
4437 {
4438 struct bfd_hash_entry *p;
4439 struct elf_link_hash_entry *h;
4440
4441 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4442 {
4443 h = (struct elf_link_hash_entry *) p;
4444 if (h->root.type == bfd_link_hash_warning)
4445 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4446 if (h->dynindx >= old_dynsymcount)
4447 _bfd_elf_strtab_delref (htab->dynstr, h->dynstr_index);
4448
4449 memcpy (p, old_ent, htab->root.table.entsize);
4450 old_ent = (char *) old_ent + htab->root.table.entsize;
4451 h = (struct elf_link_hash_entry *) p;
4452 if (h->root.type == bfd_link_hash_warning)
4453 {
4454 memcpy (h->root.u.i.link, old_ent, htab->root.table.entsize);
4455 old_ent = (char *) old_ent + htab->root.table.entsize;
4456 }
4457 }
4458 }
4459
4460 /* Make a special call to the linker "notice" function to
4461 tell it that symbols added for crefs may need to be removed. */
4462 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4463 notice_not_needed))
4464 return FALSE;
4465
4466 free (old_tab);
4467 objalloc_free_block ((struct objalloc *) htab->root.table.memory,
4468 alloc_mark);
4469 if (nondeflt_vers != NULL)
4470 free (nondeflt_vers);
4471 return TRUE;
4472 }
4473
4474 if (old_tab != NULL)
4475 {
4476 if (!(*info->callbacks->notice) (info, NULL, abfd, NULL,
4477 notice_needed))
4478 return FALSE;
4479 free (old_tab);
4480 old_tab = NULL;
4481 }
4482
4483 /* Now that all the symbols from this input file are created, handle
4484 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4485 if (nondeflt_vers != NULL)
4486 {
4487 bfd_size_type cnt, symidx;
4488
4489 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4490 {
4491 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4492 char *shortname, *p;
4493
4494 p = strchr (h->root.root.string, ELF_VER_CHR);
4495 if (p == NULL
4496 || (h->root.type != bfd_link_hash_defined
4497 && h->root.type != bfd_link_hash_defweak))
4498 continue;
4499
4500 amt = p - h->root.root.string;
4501 shortname = bfd_malloc (amt + 1);
4502 memcpy (shortname, h->root.root.string, amt);
4503 shortname[amt] = '\0';
4504
4505 hi = (struct elf_link_hash_entry *)
4506 bfd_link_hash_lookup (&htab->root, shortname,
4507 FALSE, FALSE, FALSE);
4508 if (hi != NULL
4509 && hi->root.type == h->root.type
4510 && hi->root.u.def.value == h->root.u.def.value
4511 && hi->root.u.def.section == h->root.u.def.section)
4512 {
4513 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4514 hi->root.type = bfd_link_hash_indirect;
4515 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4516 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
4517 sym_hash = elf_sym_hashes (abfd);
4518 if (sym_hash)
4519 for (symidx = 0; symidx < extsymcount; ++symidx)
4520 if (sym_hash[symidx] == hi)
4521 {
4522 sym_hash[symidx] = h;
4523 break;
4524 }
4525 }
4526 free (shortname);
4527 }
4528 free (nondeflt_vers);
4529 nondeflt_vers = NULL;
4530 }
4531
4532 /* Now set the weakdefs field correctly for all the weak defined
4533 symbols we found. The only way to do this is to search all the
4534 symbols. Since we only need the information for non functions in
4535 dynamic objects, that's the only time we actually put anything on
4536 the list WEAKS. We need this information so that if a regular
4537 object refers to a symbol defined weakly in a dynamic object, the
4538 real symbol in the dynamic object is also put in the dynamic
4539 symbols; we also must arrange for both symbols to point to the
4540 same memory location. We could handle the general case of symbol
4541 aliasing, but a general symbol alias can only be generated in
4542 assembler code, handling it correctly would be very time
4543 consuming, and other ELF linkers don't handle general aliasing
4544 either. */
4545 if (weaks != NULL)
4546 {
4547 struct elf_link_hash_entry **hpp;
4548 struct elf_link_hash_entry **hppend;
4549 struct elf_link_hash_entry **sorted_sym_hash;
4550 struct elf_link_hash_entry *h;
4551 size_t sym_count;
4552
4553 /* Since we have to search the whole symbol list for each weak
4554 defined symbol, search time for N weak defined symbols will be
4555 O(N^2). Binary search will cut it down to O(NlogN). */
4556 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4557 sorted_sym_hash = bfd_malloc (amt);
4558 if (sorted_sym_hash == NULL)
4559 goto error_return;
4560 sym_hash = sorted_sym_hash;
4561 hpp = elf_sym_hashes (abfd);
4562 hppend = hpp + extsymcount;
4563 sym_count = 0;
4564 for (; hpp < hppend; hpp++)
4565 {
4566 h = *hpp;
4567 if (h != NULL
4568 && h->root.type == bfd_link_hash_defined
4569 && !bed->is_function_type (h->type))
4570 {
4571 *sym_hash = h;
4572 sym_hash++;
4573 sym_count++;
4574 }
4575 }
4576
4577 qsort (sorted_sym_hash, sym_count,
4578 sizeof (struct elf_link_hash_entry *),
4579 elf_sort_symbol);
4580
4581 while (weaks != NULL)
4582 {
4583 struct elf_link_hash_entry *hlook;
4584 asection *slook;
4585 bfd_vma vlook;
4586 long ilook;
4587 size_t i, j, idx;
4588
4589 hlook = weaks;
4590 weaks = hlook->u.weakdef;
4591 hlook->u.weakdef = NULL;
4592
4593 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4594 || hlook->root.type == bfd_link_hash_defweak
4595 || hlook->root.type == bfd_link_hash_common
4596 || hlook->root.type == bfd_link_hash_indirect);
4597 slook = hlook->root.u.def.section;
4598 vlook = hlook->root.u.def.value;
4599
4600 ilook = -1;
4601 i = 0;
4602 j = sym_count;
4603 while (i < j)
4604 {
4605 bfd_signed_vma vdiff;
4606 idx = (i + j) / 2;
4607 h = sorted_sym_hash [idx];
4608 vdiff = vlook - h->root.u.def.value;
4609 if (vdiff < 0)
4610 j = idx;
4611 else if (vdiff > 0)
4612 i = idx + 1;
4613 else
4614 {
4615 long sdiff = slook->id - h->root.u.def.section->id;
4616 if (sdiff < 0)
4617 j = idx;
4618 else if (sdiff > 0)
4619 i = idx + 1;
4620 else
4621 {
4622 ilook = idx;
4623 break;
4624 }
4625 }
4626 }
4627
4628 /* We didn't find a value/section match. */
4629 if (ilook == -1)
4630 continue;
4631
4632 for (i = ilook; i < sym_count; i++)
4633 {
4634 h = sorted_sym_hash [i];
4635
4636 /* Stop if value or section doesn't match. */
4637 if (h->root.u.def.value != vlook
4638 || h->root.u.def.section != slook)
4639 break;
4640 else if (h != hlook)
4641 {
4642 hlook->u.weakdef = h;
4643
4644 /* If the weak definition is in the list of dynamic
4645 symbols, make sure the real definition is put
4646 there as well. */
4647 if (hlook->dynindx != -1 && h->dynindx == -1)
4648 {
4649 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4650 goto error_return;
4651 }
4652
4653 /* If the real definition is in the list of dynamic
4654 symbols, make sure the weak definition is put
4655 there as well. If we don't do this, then the
4656 dynamic loader might not merge the entries for the
4657 real definition and the weak definition. */
4658 if (h->dynindx != -1 && hlook->dynindx == -1)
4659 {
4660 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4661 goto error_return;
4662 }
4663 break;
4664 }
4665 }
4666 }
4667
4668 free (sorted_sym_hash);
4669 }
4670
4671 if (bed->check_directives)
4672 (*bed->check_directives) (abfd, info);
4673
4674 /* If this object is the same format as the output object, and it is
4675 not a shared library, then let the backend look through the
4676 relocs.
4677
4678 This is required to build global offset table entries and to
4679 arrange for dynamic relocs. It is not required for the
4680 particular common case of linking non PIC code, even when linking
4681 against shared libraries, but unfortunately there is no way of
4682 knowing whether an object file has been compiled PIC or not.
4683 Looking through the relocs is not particularly time consuming.
4684 The problem is that we must either (1) keep the relocs in memory,
4685 which causes the linker to require additional runtime memory or
4686 (2) read the relocs twice from the input file, which wastes time.
4687 This would be a good case for using mmap.
4688
4689 I have no idea how to handle linking PIC code into a file of a
4690 different format. It probably can't be done. */
4691 if (! dynamic
4692 && is_elf_hash_table (htab)
4693 && bed->check_relocs != NULL
4694 && (*bed->relocs_compatible) (abfd->xvec, htab->root.creator))
4695 {
4696 asection *o;
4697
4698 for (o = abfd->sections; o != NULL; o = o->next)
4699 {
4700 Elf_Internal_Rela *internal_relocs;
4701 bfd_boolean ok;
4702
4703 if ((o->flags & SEC_RELOC) == 0
4704 || o->reloc_count == 0
4705 || ((info->strip == strip_all || info->strip == strip_debugger)
4706 && (o->flags & SEC_DEBUGGING) != 0)
4707 || bfd_is_abs_section (o->output_section))
4708 continue;
4709
4710 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4711 info->keep_memory);
4712 if (internal_relocs == NULL)
4713 goto error_return;
4714
4715 ok = (*bed->check_relocs) (abfd, info, o, internal_relocs);
4716
4717 if (elf_section_data (o)->relocs != internal_relocs)
4718 free (internal_relocs);
4719
4720 if (! ok)
4721 goto error_return;
4722 }
4723 }
4724
4725 /* If this is a non-traditional link, try to optimize the handling
4726 of the .stab/.stabstr sections. */
4727 if (! dynamic
4728 && ! info->traditional_format
4729 && is_elf_hash_table (htab)
4730 && (info->strip != strip_all && info->strip != strip_debugger))
4731 {
4732 asection *stabstr;
4733
4734 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4735 if (stabstr != NULL)
4736 {
4737 bfd_size_type string_offset = 0;
4738 asection *stab;
4739
4740 for (stab = abfd->sections; stab; stab = stab->next)
4741 if (CONST_STRNEQ (stab->name, ".stab")
4742 && (!stab->name[5] ||
4743 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4744 && (stab->flags & SEC_MERGE) == 0
4745 && !bfd_is_abs_section (stab->output_section))
4746 {
4747 struct bfd_elf_section_data *secdata;
4748
4749 secdata = elf_section_data (stab);
4750 if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
4751 stabstr, &secdata->sec_info,
4752 &string_offset))
4753 goto error_return;
4754 if (secdata->sec_info)
4755 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4756 }
4757 }
4758 }
4759
4760 if (is_elf_hash_table (htab) && add_needed)
4761 {
4762 /* Add this bfd to the loaded list. */
4763 struct elf_link_loaded_list *n;
4764
4765 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4766 if (n == NULL)
4767 goto error_return;
4768 n->abfd = abfd;
4769 n->next = htab->loaded;
4770 htab->loaded = n;
4771 }
4772
4773 return TRUE;
4774
4775 error_free_vers:
4776 if (old_tab != NULL)
4777 free (old_tab);
4778 if (nondeflt_vers != NULL)
4779 free (nondeflt_vers);
4780 if (extversym != NULL)
4781 free (extversym);
4782 error_free_sym:
4783 if (isymbuf != NULL)
4784 free (isymbuf);
4785 error_return:
4786 return FALSE;
4787 }
4788
4789 /* Return the linker hash table entry of a symbol that might be
4790 satisfied by an archive symbol. Return -1 on error. */
4791
4792 struct elf_link_hash_entry *
_bfd_elf_archive_symbol_lookup(bfd * abfd,struct bfd_link_info * info,const char * name)4793 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4794 struct bfd_link_info *info,
4795 const char *name)
4796 {
4797 struct elf_link_hash_entry *h;
4798 char *p, *copy;
4799 size_t len, first;
4800
4801 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4802 if (h != NULL)
4803 return h;
4804
4805 /* If this is a default version (the name contains @@), look up the
4806 symbol again with only one `@' as well as without the version.
4807 The effect is that references to the symbol with and without the
4808 version will be matched by the default symbol in the archive. */
4809
4810 p = strchr (name, ELF_VER_CHR);
4811 if (p == NULL || p[1] != ELF_VER_CHR)
4812 return h;
4813
4814 /* First check with only one `@'. */
4815 len = strlen (name);
4816 copy = bfd_alloc (abfd, len);
4817 if (copy == NULL)
4818 return (struct elf_link_hash_entry *)(intptr_t)-1;
4819
4820 first = p - name + 1;
4821 memcpy (copy, name, first);
4822 memcpy (copy + first, name + first + 1, len - first);
4823
4824 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4825 if (h == NULL)
4826 {
4827 /* We also need to check references to the symbol without the
4828 version. */
4829 copy[first - 1] = '\0';
4830 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4831 FALSE, FALSE, FALSE);
4832 }
4833
4834 bfd_release (abfd, copy);
4835 return h;
4836 }
4837
4838 /* Add symbols from an ELF archive file to the linker hash table. We
4839 don't use _bfd_generic_link_add_archive_symbols because of a
4840 problem which arises on UnixWare. The UnixWare libc.so is an
4841 archive which includes an entry libc.so.1 which defines a bunch of
4842 symbols. The libc.so archive also includes a number of other
4843 object files, which also define symbols, some of which are the same
4844 as those defined in libc.so.1. Correct linking requires that we
4845 consider each object file in turn, and include it if it defines any
4846 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4847 this; it looks through the list of undefined symbols, and includes
4848 any object file which defines them. When this algorithm is used on
4849 UnixWare, it winds up pulling in libc.so.1 early and defining a
4850 bunch of symbols. This means that some of the other objects in the
4851 archive are not included in the link, which is incorrect since they
4852 precede libc.so.1 in the archive.
4853
4854 Fortunately, ELF archive handling is simpler than that done by
4855 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4856 oddities. In ELF, if we find a symbol in the archive map, and the
4857 symbol is currently undefined, we know that we must pull in that
4858 object file.
4859
4860 Unfortunately, we do have to make multiple passes over the symbol
4861 table until nothing further is resolved. */
4862
4863 static bfd_boolean
elf_link_add_archive_symbols(bfd * abfd,struct bfd_link_info * info)4864 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4865 {
4866 symindex c;
4867 bfd_boolean *defined = NULL;
4868 bfd_boolean *included = NULL;
4869 carsym *symdefs;
4870 bfd_boolean loop;
4871 bfd_size_type amt;
4872 const struct elf_backend_data *bed;
4873 struct elf_link_hash_entry * (*archive_symbol_lookup)
4874 (bfd *, struct bfd_link_info *, const char *);
4875
4876 if (! bfd_has_map (abfd))
4877 {
4878 /* An empty archive is a special case. */
4879 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4880 return TRUE;
4881 bfd_set_error (bfd_error_no_armap);
4882 return FALSE;
4883 }
4884
4885 /* Keep track of all symbols we know to be already defined, and all
4886 files we know to be already included. This is to speed up the
4887 second and subsequent passes. */
4888 c = bfd_ardata (abfd)->symdef_count;
4889 if (c == 0)
4890 return TRUE;
4891 amt = c;
4892 amt *= sizeof (bfd_boolean);
4893 defined = bfd_zmalloc (amt);
4894 included = bfd_zmalloc (amt);
4895 if (defined == NULL || included == NULL)
4896 goto error_return;
4897
4898 symdefs = bfd_ardata (abfd)->symdefs;
4899 bed = get_elf_backend_data (abfd);
4900 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4901
4902 do
4903 {
4904 file_ptr last;
4905 symindex i;
4906 carsym *symdef;
4907 carsym *symdefend;
4908
4909 loop = FALSE;
4910 last = -1;
4911
4912 symdef = symdefs;
4913 symdefend = symdef + c;
4914 for (i = 0; symdef < symdefend; symdef++, i++)
4915 {
4916 struct elf_link_hash_entry *h;
4917 bfd *element;
4918 struct bfd_link_hash_entry *undefs_tail;
4919 symindex mark;
4920
4921 if (defined[i] || included[i])
4922 continue;
4923 if (symdef->file_offset == last)
4924 {
4925 included[i] = TRUE;
4926 continue;
4927 }
4928
4929 h = archive_symbol_lookup (abfd, info, symdef->name);
4930 if (h == (struct elf_link_hash_entry *)(intptr_t)-1)
4931 goto error_return;
4932
4933 if (h == NULL)
4934 continue;
4935
4936 if (h->root.type == bfd_link_hash_common)
4937 {
4938 /* We currently have a common symbol. The archive map contains
4939 a reference to this symbol, so we may want to include it. We
4940 only want to include it however, if this archive element
4941 contains a definition of the symbol, not just another common
4942 declaration of it.
4943
4944 Unfortunately some archivers (including GNU ar) will put
4945 declarations of common symbols into their archive maps, as
4946 well as real definitions, so we cannot just go by the archive
4947 map alone. Instead we must read in the element's symbol
4948 table and check that to see what kind of symbol definition
4949 this is. */
4950 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4951 continue;
4952 }
4953 else if (h->root.type != bfd_link_hash_undefined)
4954 {
4955 if (h->root.type != bfd_link_hash_undefweak)
4956 defined[i] = TRUE;
4957 continue;
4958 }
4959
4960 /* We need to include this archive member. */
4961 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4962 if (element == NULL)
4963 goto error_return;
4964
4965 if (! bfd_check_format (element, bfd_object))
4966 goto error_return;
4967
4968 /* Doublecheck that we have not included this object
4969 already--it should be impossible, but there may be
4970 something wrong with the archive. */
4971 if (element->archive_pass != 0)
4972 {
4973 bfd_set_error (bfd_error_bad_value);
4974 goto error_return;
4975 }
4976 element->archive_pass = 1;
4977
4978 undefs_tail = info->hash->undefs_tail;
4979
4980 if (! (*info->callbacks->add_archive_element) (info, element,
4981 symdef->name))
4982 goto error_return;
4983 if (! bfd_link_add_symbols (element, info))
4984 goto error_return;
4985
4986 /* If there are any new undefined symbols, we need to make
4987 another pass through the archive in order to see whether
4988 they can be defined. FIXME: This isn't perfect, because
4989 common symbols wind up on undefs_tail and because an
4990 undefined symbol which is defined later on in this pass
4991 does not require another pass. This isn't a bug, but it
4992 does make the code less efficient than it could be. */
4993 if (undefs_tail != info->hash->undefs_tail)
4994 loop = TRUE;
4995
4996 /* Look backward to mark all symbols from this object file
4997 which we have already seen in this pass. */
4998 mark = i;
4999 do
5000 {
5001 included[mark] = TRUE;
5002 if (mark == 0)
5003 break;
5004 --mark;
5005 }
5006 while (symdefs[mark].file_offset == symdef->file_offset);
5007
5008 /* We mark subsequent symbols from this object file as we go
5009 on through the loop. */
5010 last = symdef->file_offset;
5011 }
5012 }
5013 while (loop);
5014
5015 free (defined);
5016 free (included);
5017
5018 return TRUE;
5019
5020 error_return:
5021 if (defined != NULL)
5022 free (defined);
5023 if (included != NULL)
5024 free (included);
5025 return FALSE;
5026 }
5027
5028 /* Given an ELF BFD, add symbols to the global hash table as
5029 appropriate. */
5030
5031 bfd_boolean
bfd_elf_link_add_symbols(bfd * abfd,struct bfd_link_info * info)5032 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
5033 {
5034 switch (bfd_get_format (abfd))
5035 {
5036 case bfd_object:
5037 return elf_link_add_object_symbols (abfd, info);
5038 case bfd_archive:
5039 return elf_link_add_archive_symbols (abfd, info);
5040 default:
5041 bfd_set_error (bfd_error_wrong_format);
5042 return FALSE;
5043 }
5044 }
5045
5046 /* This function will be called though elf_link_hash_traverse to store
5047 all hash value of the exported symbols in an array. */
5048
5049 static bfd_boolean
elf_collect_hash_codes(struct elf_link_hash_entry * h,void * data)5050 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
5051 {
5052 unsigned long **valuep = data;
5053 const char *name;
5054 char *p;
5055 unsigned long ha;
5056 char *alc = NULL;
5057
5058 if (h->root.type == bfd_link_hash_warning)
5059 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5060
5061 /* Ignore indirect symbols. These are added by the versioning code. */
5062 if (h->dynindx == -1)
5063 return TRUE;
5064
5065 name = h->root.root.string;
5066 p = strchr (name, ELF_VER_CHR);
5067 if (p != NULL)
5068 {
5069 alc = bfd_malloc (p - name + 1);
5070 memcpy (alc, name, p - name);
5071 alc[p - name] = '\0';
5072 name = alc;
5073 }
5074
5075 /* Compute the hash value. */
5076 ha = bfd_elf_hash (name);
5077
5078 /* Store the found hash value in the array given as the argument. */
5079 *(*valuep)++ = ha;
5080
5081 /* And store it in the struct so that we can put it in the hash table
5082 later. */
5083 h->u.elf_hash_value = ha;
5084
5085 if (alc != NULL)
5086 free (alc);
5087
5088 return TRUE;
5089 }
5090
5091 struct collect_gnu_hash_codes
5092 {
5093 bfd *output_bfd;
5094 const struct elf_backend_data *bed;
5095 unsigned long int nsyms;
5096 unsigned long int maskbits;
5097 unsigned long int *hashcodes;
5098 unsigned long int *hashval;
5099 unsigned long int *indx;
5100 unsigned long int *counts;
5101 bfd_vma *bitmask;
5102 bfd_byte *contents;
5103 long int min_dynindx;
5104 unsigned long int bucketcount;
5105 unsigned long int symindx;
5106 long int local_indx;
5107 long int shift1, shift2;
5108 unsigned long int mask;
5109 };
5110
5111 /* This function will be called though elf_link_hash_traverse to store
5112 all hash value of the exported symbols in an array. */
5113
5114 static bfd_boolean
elf_collect_gnu_hash_codes(struct elf_link_hash_entry * h,void * data)5115 elf_collect_gnu_hash_codes (struct elf_link_hash_entry *h, void *data)
5116 {
5117 struct collect_gnu_hash_codes *s = data;
5118 const char *name;
5119 char *p;
5120 unsigned long ha;
5121 char *alc = NULL;
5122
5123 if (h->root.type == bfd_link_hash_warning)
5124 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5125
5126 /* Ignore indirect symbols. These are added by the versioning code. */
5127 if (h->dynindx == -1)
5128 return TRUE;
5129
5130 /* Ignore also local symbols and undefined symbols. */
5131 if (! (*s->bed->elf_hash_symbol) (h))
5132 return TRUE;
5133
5134 name = h->root.root.string;
5135 p = strchr (name, ELF_VER_CHR);
5136 if (p != NULL)
5137 {
5138 alc = bfd_malloc (p - name + 1);
5139 memcpy (alc, name, p - name);
5140 alc[p - name] = '\0';
5141 name = alc;
5142 }
5143
5144 /* Compute the hash value. */
5145 ha = bfd_elf_gnu_hash (name);
5146
5147 /* Store the found hash value in the array for compute_bucket_count,
5148 and also for .dynsym reordering purposes. */
5149 s->hashcodes[s->nsyms] = ha;
5150 s->hashval[h->dynindx] = ha;
5151 ++s->nsyms;
5152 if (s->min_dynindx < 0 || s->min_dynindx > h->dynindx)
5153 s->min_dynindx = h->dynindx;
5154
5155 if (alc != NULL)
5156 free (alc);
5157
5158 return TRUE;
5159 }
5160
5161 /* This function will be called though elf_link_hash_traverse to do
5162 final dynaminc symbol renumbering. */
5163
5164 static bfd_boolean
elf_renumber_gnu_hash_syms(struct elf_link_hash_entry * h,void * data)5165 elf_renumber_gnu_hash_syms (struct elf_link_hash_entry *h, void *data)
5166 {
5167 struct collect_gnu_hash_codes *s = data;
5168 unsigned long int bucket;
5169 unsigned long int val;
5170
5171 if (h->root.type == bfd_link_hash_warning)
5172 h = (struct elf_link_hash_entry *) h->root.u.i.link;
5173
5174 /* Ignore indirect symbols. */
5175 if (h->dynindx == -1)
5176 return TRUE;
5177
5178 /* Ignore also local symbols and undefined symbols. */
5179 if (! (*s->bed->elf_hash_symbol) (h))
5180 {
5181 if (h->dynindx >= s->min_dynindx)
5182 h->dynindx = s->local_indx++;
5183 return TRUE;
5184 }
5185
5186 bucket = s->hashval[h->dynindx] % s->bucketcount;
5187 val = (s->hashval[h->dynindx] >> s->shift1)
5188 & ((s->maskbits >> s->shift1) - 1);
5189 s->bitmask[val] |= ((bfd_vma) 1) << (s->hashval[h->dynindx] & s->mask);
5190 s->bitmask[val]
5191 |= ((bfd_vma) 1) << ((s->hashval[h->dynindx] >> s->shift2) & s->mask);
5192 val = s->hashval[h->dynindx] & ~(unsigned long int) 1;
5193 if (s->counts[bucket] == 1)
5194 /* Last element terminates the chain. */
5195 val |= 1;
5196 bfd_put_32 (s->output_bfd, val,
5197 s->contents + (s->indx[bucket] - s->symindx) * 4);
5198 --s->counts[bucket];
5199 h->dynindx = s->indx[bucket]++;
5200 return TRUE;
5201 }
5202
5203 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
5204
5205 bfd_boolean
_bfd_elf_hash_symbol(struct elf_link_hash_entry * h)5206 _bfd_elf_hash_symbol (struct elf_link_hash_entry *h)
5207 {
5208 return !(h->forced_local
5209 || h->root.type == bfd_link_hash_undefined
5210 || h->root.type == bfd_link_hash_undefweak
5211 || ((h->root.type == bfd_link_hash_defined
5212 || h->root.type == bfd_link_hash_defweak)
5213 && h->root.u.def.section->output_section == NULL));
5214 }
5215
5216 /* Array used to determine the number of hash table buckets to use
5217 based on the number of symbols there are. If there are fewer than
5218 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
5219 fewer than 37 we use 17 buckets, and so forth. We never use more
5220 than 32771 buckets. */
5221
5222 static const size_t elf_buckets[] =
5223 {
5224 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
5225 16411, 32771, 0
5226 };
5227
5228 /* Compute bucket count for hashing table. We do not use a static set
5229 of possible tables sizes anymore. Instead we determine for all
5230 possible reasonable sizes of the table the outcome (i.e., the
5231 number of collisions etc) and choose the best solution. The
5232 weighting functions are not too simple to allow the table to grow
5233 without bounds. Instead one of the weighting factors is the size.
5234 Therefore the result is always a good payoff between few collisions
5235 (= short chain lengths) and table size. */
5236 static size_t
compute_bucket_count(struct bfd_link_info * info,unsigned long int * hashcodes,unsigned long int nsyms,int gnu_hash)5237 compute_bucket_count (struct bfd_link_info *info, unsigned long int *hashcodes,
5238 unsigned long int nsyms, int gnu_hash)
5239 {
5240 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
5241 size_t best_size = 0;
5242 unsigned long int i;
5243 bfd_size_type amt;
5244
5245 /* We have a problem here. The following code to optimize the table
5246 size requires an integer type with more the 32 bits. If
5247 BFD_HOST_U_64_BIT is set we know about such a type. */
5248 #ifdef BFD_HOST_U_64_BIT
5249 if (info->optimize)
5250 {
5251 size_t minsize;
5252 size_t maxsize;
5253 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
5254 bfd *dynobj = elf_hash_table (info)->dynobj;
5255 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
5256 unsigned long int *counts;
5257
5258 /* Possible optimization parameters: if we have NSYMS symbols we say
5259 that the hashing table must at least have NSYMS/4 and at most
5260 2*NSYMS buckets. */
5261 minsize = nsyms / 4;
5262 if (minsize == 0)
5263 minsize = 1;
5264 best_size = maxsize = nsyms * 2;
5265 if (gnu_hash)
5266 {
5267 if (minsize < 2)
5268 minsize = 2;
5269 if ((best_size & 31) == 0)
5270 ++best_size;
5271 }
5272
5273 /* Create array where we count the collisions in. We must use bfd_malloc
5274 since the size could be large. */
5275 amt = maxsize;
5276 amt *= sizeof (unsigned long int);
5277 counts = bfd_malloc (amt);
5278 if (counts == NULL)
5279 return 0;
5280
5281 /* Compute the "optimal" size for the hash table. The criteria is a
5282 minimal chain length. The minor criteria is (of course) the size
5283 of the table. */
5284 for (i = minsize; i < maxsize; ++i)
5285 {
5286 /* Walk through the array of hashcodes and count the collisions. */
5287 BFD_HOST_U_64_BIT max;
5288 unsigned long int j;
5289 unsigned long int fact;
5290
5291 if (gnu_hash && (i & 31) == 0)
5292 continue;
5293
5294 memset (counts, '\0', i * sizeof (unsigned long int));
5295
5296 /* Determine how often each hash bucket is used. */
5297 for (j = 0; j < nsyms; ++j)
5298 ++counts[hashcodes[j] % i];
5299
5300 /* For the weight function we need some information about the
5301 pagesize on the target. This is information need not be 100%
5302 accurate. Since this information is not available (so far) we
5303 define it here to a reasonable default value. If it is crucial
5304 to have a better value some day simply define this value. */
5305 # ifndef BFD_TARGET_PAGESIZE
5306 # define BFD_TARGET_PAGESIZE (4096)
5307 # endif
5308
5309 /* We in any case need 2 + DYNSYMCOUNT entries for the size values
5310 and the chains. */
5311 max = (2 + dynsymcount) * bed->s->sizeof_hash_entry;
5312
5313 # if 1
5314 /* Variant 1: optimize for short chains. We add the squares
5315 of all the chain lengths (which favors many small chain
5316 over a few long chains). */
5317 for (j = 0; j < i; ++j)
5318 max += counts[j] * counts[j];
5319
5320 /* This adds penalties for the overall size of the table. */
5321 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5322 max *= fact * fact;
5323 # else
5324 /* Variant 2: Optimize a lot more for small table. Here we
5325 also add squares of the size but we also add penalties for
5326 empty slots (the +1 term). */
5327 for (j = 0; j < i; ++j)
5328 max += (1 + counts[j]) * (1 + counts[j]);
5329
5330 /* The overall size of the table is considered, but not as
5331 strong as in variant 1, where it is squared. */
5332 fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
5333 max *= fact;
5334 # endif
5335
5336 /* Compare with current best results. */
5337 if (max < best_chlen)
5338 {
5339 best_chlen = max;
5340 best_size = i;
5341 }
5342 }
5343
5344 free (counts);
5345 }
5346 else
5347 #endif /* defined (BFD_HOST_U_64_BIT) */
5348 {
5349 /* This is the fallback solution if no 64bit type is available or if we
5350 are not supposed to spend much time on optimizations. We select the
5351 bucket count using a fixed set of numbers. */
5352 for (i = 0; elf_buckets[i] != 0; i++)
5353 {
5354 best_size = elf_buckets[i];
5355 if (nsyms < elf_buckets[i + 1])
5356 break;
5357 }
5358 if (gnu_hash && best_size < 2)
5359 best_size = 2;
5360 }
5361
5362 return best_size;
5363 }
5364
5365 /* Set up the sizes and contents of the ELF dynamic sections. This is
5366 called by the ELF linker emulation before_allocation routine. We
5367 must set the sizes of the sections before the linker sets the
5368 addresses of the various sections. */
5369
5370 bfd_boolean
bfd_elf_size_dynamic_sections(bfd * output_bfd,const char * soname,const char * rpath,const char * filter_shlib,const char * const * auxiliary_filters,struct bfd_link_info * info,asection ** sinterpptr,struct bfd_elf_version_tree * verdefs)5371 bfd_elf_size_dynamic_sections (bfd *output_bfd,
5372 const char *soname,
5373 const char *rpath,
5374 const char *filter_shlib,
5375 const char * const *auxiliary_filters,
5376 struct bfd_link_info *info,
5377 asection **sinterpptr,
5378 struct bfd_elf_version_tree *verdefs)
5379 {
5380 bfd_size_type soname_indx;
5381 bfd *dynobj;
5382 const struct elf_backend_data *bed;
5383 struct elf_assign_sym_version_info asvinfo;
5384
5385 *sinterpptr = NULL;
5386
5387 soname_indx = (bfd_size_type) -1;
5388
5389 if (!is_elf_hash_table (info->hash))
5390 return TRUE;
5391
5392 bed = get_elf_backend_data (output_bfd);
5393 elf_tdata (output_bfd)->relro = info->relro;
5394 if (info->execstack)
5395 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
5396 else if (info->noexecstack)
5397 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
5398 else
5399 {
5400 bfd *inputobj;
5401 asection *notesec = NULL;
5402 int exec = 0;
5403
5404 for (inputobj = info->input_bfds;
5405 inputobj;
5406 inputobj = inputobj->link_next)
5407 {
5408 asection *s;
5409
5410 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
5411 continue;
5412 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
5413 if (s)
5414 {
5415 if (s->flags & SEC_CODE)
5416 exec = PF_X;
5417 notesec = s;
5418 }
5419 else if (bed->default_execstack)
5420 exec = PF_X;
5421 }
5422 if (notesec)
5423 {
5424 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
5425 if (exec && info->relocatable
5426 && notesec->output_section != bfd_abs_section_ptr)
5427 notesec->output_section->flags |= SEC_CODE;
5428 }
5429 }
5430
5431 /* Any syms created from now on start with -1 in
5432 got.refcount/offset and plt.refcount/offset. */
5433 elf_hash_table (info)->init_got_refcount
5434 = elf_hash_table (info)->init_got_offset;
5435 elf_hash_table (info)->init_plt_refcount
5436 = elf_hash_table (info)->init_plt_offset;
5437
5438 /* The backend may have to create some sections regardless of whether
5439 we're dynamic or not. */
5440 if (bed->elf_backend_always_size_sections
5441 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
5442 return FALSE;
5443
5444 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5445 return FALSE;
5446
5447 dynobj = elf_hash_table (info)->dynobj;
5448
5449 /* If there were no dynamic objects in the link, there is nothing to
5450 do here. */
5451 if (dynobj == NULL)
5452 return TRUE;
5453
5454 if (elf_hash_table (info)->dynamic_sections_created)
5455 {
5456 struct elf_info_failed eif;
5457 struct elf_link_hash_entry *h;
5458 asection *dynstr;
5459 struct bfd_elf_version_tree *t;
5460 struct bfd_elf_version_expr *d;
5461 asection *s;
5462 bfd_boolean all_defined;
5463
5464 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5465 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5466
5467 if (soname != NULL)
5468 {
5469 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5470 soname, TRUE);
5471 if (soname_indx == (bfd_size_type) -1
5472 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5473 return FALSE;
5474 }
5475
5476 if (info->symbolic)
5477 {
5478 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5479 return FALSE;
5480 info->flags |= DF_SYMBOLIC;
5481 }
5482
5483 if (rpath != NULL)
5484 {
5485 bfd_size_type indx;
5486
5487 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5488 TRUE);
5489 if (indx == (bfd_size_type) -1
5490 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5491 return FALSE;
5492
5493 if (info->new_dtags)
5494 {
5495 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5496 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5497 return FALSE;
5498 }
5499 }
5500
5501 if (filter_shlib != NULL)
5502 {
5503 bfd_size_type indx;
5504
5505 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5506 filter_shlib, TRUE);
5507 if (indx == (bfd_size_type) -1
5508 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5509 return FALSE;
5510 }
5511
5512 if (auxiliary_filters != NULL)
5513 {
5514 const char * const *p;
5515
5516 for (p = auxiliary_filters; *p != NULL; p++)
5517 {
5518 bfd_size_type indx;
5519
5520 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5521 *p, TRUE);
5522 if (indx == (bfd_size_type) -1
5523 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5524 return FALSE;
5525 }
5526 }
5527
5528 eif.info = info;
5529 eif.verdefs = verdefs;
5530 eif.failed = FALSE;
5531
5532 /* If we are supposed to export all symbols into the dynamic symbol
5533 table (this is not the normal case), then do so. */
5534 if (info->export_dynamic
5535 || (info->executable && info->dynamic))
5536 {
5537 elf_link_hash_traverse (elf_hash_table (info),
5538 _bfd_elf_export_symbol,
5539 &eif);
5540 if (eif.failed)
5541 return FALSE;
5542 }
5543
5544 /* Make all global versions with definition. */
5545 for (t = verdefs; t != NULL; t = t->next)
5546 for (d = t->globals.list; d != NULL; d = d->next)
5547 if (!d->symver && d->symbol)
5548 {
5549 const char *verstr, *name;
5550 size_t namelen, verlen, newlen;
5551 char *newname, *p;
5552 struct elf_link_hash_entry *newh;
5553
5554 name = d->symbol;
5555 namelen = strlen (name);
5556 verstr = t->name;
5557 verlen = strlen (verstr);
5558 newlen = namelen + verlen + 3;
5559
5560 newname = bfd_malloc (newlen);
5561 if (newname == NULL)
5562 return FALSE;
5563 memcpy (newname, name, namelen);
5564
5565 /* Check the hidden versioned definition. */
5566 p = newname + namelen;
5567 *p++ = ELF_VER_CHR;
5568 memcpy (p, verstr, verlen + 1);
5569 newh = elf_link_hash_lookup (elf_hash_table (info),
5570 newname, FALSE, FALSE,
5571 FALSE);
5572 if (newh == NULL
5573 || (newh->root.type != bfd_link_hash_defined
5574 && newh->root.type != bfd_link_hash_defweak))
5575 {
5576 /* Check the default versioned definition. */
5577 *p++ = ELF_VER_CHR;
5578 memcpy (p, verstr, verlen + 1);
5579 newh = elf_link_hash_lookup (elf_hash_table (info),
5580 newname, FALSE, FALSE,
5581 FALSE);
5582 }
5583 free (newname);
5584
5585 /* Mark this version if there is a definition and it is
5586 not defined in a shared object. */
5587 if (newh != NULL
5588 && !newh->def_dynamic
5589 && (newh->root.type == bfd_link_hash_defined
5590 || newh->root.type == bfd_link_hash_defweak))
5591 d->symver = 1;
5592 }
5593
5594 /* Attach all the symbols to their version information. */
5595 asvinfo.output_bfd = output_bfd;
5596 asvinfo.info = info;
5597 asvinfo.verdefs = verdefs;
5598 asvinfo.failed = FALSE;
5599
5600 elf_link_hash_traverse (elf_hash_table (info),
5601 _bfd_elf_link_assign_sym_version,
5602 &asvinfo);
5603 if (asvinfo.failed)
5604 return FALSE;
5605
5606 if (!info->allow_undefined_version)
5607 {
5608 /* Check if all global versions have a definition. */
5609 all_defined = TRUE;
5610 for (t = verdefs; t != NULL; t = t->next)
5611 for (d = t->globals.list; d != NULL; d = d->next)
5612 if (!d->symver && !d->script)
5613 {
5614 (*_bfd_error_handler)
5615 (_("%s: undefined version: %s"),
5616 d->pattern, t->name);
5617 all_defined = FALSE;
5618 }
5619
5620 if (!all_defined)
5621 {
5622 bfd_set_error (bfd_error_bad_value);
5623 return FALSE;
5624 }
5625 }
5626
5627 /* Find all symbols which were defined in a dynamic object and make
5628 the backend pick a reasonable value for them. */
5629 elf_link_hash_traverse (elf_hash_table (info),
5630 _bfd_elf_adjust_dynamic_symbol,
5631 &eif);
5632 if (eif.failed)
5633 return FALSE;
5634
5635 /* Add some entries to the .dynamic section. We fill in some of the
5636 values later, in bfd_elf_final_link, but we must add the entries
5637 now so that we know the final size of the .dynamic section. */
5638
5639 /* If there are initialization and/or finalization functions to
5640 call then add the corresponding DT_INIT/DT_FINI entries. */
5641 h = (info->init_function
5642 ? elf_link_hash_lookup (elf_hash_table (info),
5643 info->init_function, FALSE,
5644 FALSE, FALSE)
5645 : NULL);
5646 if (h != NULL
5647 && (h->ref_regular
5648 || h->def_regular))
5649 {
5650 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5651 return FALSE;
5652 }
5653 h = (info->fini_function
5654 ? elf_link_hash_lookup (elf_hash_table (info),
5655 info->fini_function, FALSE,
5656 FALSE, FALSE)
5657 : NULL);
5658 if (h != NULL
5659 && (h->ref_regular
5660 || h->def_regular))
5661 {
5662 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5663 return FALSE;
5664 }
5665
5666 s = bfd_get_section_by_name (output_bfd, ".preinit_array");
5667 if (s != NULL && s->linker_has_input)
5668 {
5669 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5670 if (! info->executable)
5671 {
5672 bfd *sub;
5673 asection *o;
5674
5675 for (sub = info->input_bfds; sub != NULL;
5676 sub = sub->link_next)
5677 if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
5678 for (o = sub->sections; o != NULL; o = o->next)
5679 if (elf_section_data (o)->this_hdr.sh_type
5680 == SHT_PREINIT_ARRAY)
5681 {
5682 (*_bfd_error_handler)
5683 (_("%B: .preinit_array section is not allowed in DSO"),
5684 sub);
5685 break;
5686 }
5687
5688 bfd_set_error (bfd_error_nonrepresentable_section);
5689 return FALSE;
5690 }
5691
5692 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5693 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5694 return FALSE;
5695 }
5696 s = bfd_get_section_by_name (output_bfd, ".init_array");
5697 if (s != NULL && s->linker_has_input)
5698 {
5699 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5700 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5701 return FALSE;
5702 }
5703 s = bfd_get_section_by_name (output_bfd, ".fini_array");
5704 if (s != NULL && s->linker_has_input)
5705 {
5706 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5707 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5708 return FALSE;
5709 }
5710
5711 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5712 /* If .dynstr is excluded from the link, we don't want any of
5713 these tags. Strictly, we should be checking each section
5714 individually; This quick check covers for the case where
5715 someone does a /DISCARD/ : { *(*) }. */
5716 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5717 {
5718 bfd_size_type strsize;
5719
5720 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5721 if ((info->emit_hash
5722 && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
5723 || (info->emit_gnu_hash
5724 && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0))
5725 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5726 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5727 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5728 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5729 bed->s->sizeof_sym))
5730 return FALSE;
5731 }
5732 }
5733
5734 /* The backend must work out the sizes of all the other dynamic
5735 sections. */
5736 if (bed->elf_backend_size_dynamic_sections
5737 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5738 return FALSE;
5739
5740 if (elf_hash_table (info)->dynamic_sections_created)
5741 {
5742 unsigned long section_sym_count;
5743 asection *s;
5744
5745 /* Set up the version definition section. */
5746 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5747 BFD_ASSERT (s != NULL);
5748
5749 /* We may have created additional version definitions if we are
5750 just linking a regular application. */
5751 verdefs = asvinfo.verdefs;
5752
5753 /* Skip anonymous version tag. */
5754 if (verdefs != NULL && verdefs->vernum == 0)
5755 verdefs = verdefs->next;
5756
5757 if (verdefs == NULL && !info->create_default_symver)
5758 s->flags |= SEC_EXCLUDE;
5759 else
5760 {
5761 unsigned int cdefs;
5762 bfd_size_type size;
5763 struct bfd_elf_version_tree *t;
5764 bfd_byte *p;
5765 Elf_Internal_Verdef def;
5766 Elf_Internal_Verdaux defaux;
5767 struct bfd_link_hash_entry *bh;
5768 struct elf_link_hash_entry *h;
5769 const char *name;
5770
5771 cdefs = 0;
5772 size = 0;
5773
5774 /* Make space for the base version. */
5775 size += sizeof (Elf_External_Verdef);
5776 size += sizeof (Elf_External_Verdaux);
5777 ++cdefs;
5778
5779 /* Make space for the default version. */
5780 if (info->create_default_symver)
5781 {
5782 size += sizeof (Elf_External_Verdef);
5783 ++cdefs;
5784 }
5785
5786 for (t = verdefs; t != NULL; t = t->next)
5787 {
5788 struct bfd_elf_version_deps *n;
5789
5790 size += sizeof (Elf_External_Verdef);
5791 size += sizeof (Elf_External_Verdaux);
5792 ++cdefs;
5793
5794 for (n = t->deps; n != NULL; n = n->next)
5795 size += sizeof (Elf_External_Verdaux);
5796 }
5797
5798 s->size = size;
5799 s->contents = bfd_alloc (output_bfd, s->size);
5800 if (s->contents == NULL && s->size != 0)
5801 return FALSE;
5802
5803 /* Fill in the version definition section. */
5804
5805 p = s->contents;
5806
5807 def.vd_version = VER_DEF_CURRENT;
5808 def.vd_flags = VER_FLG_BASE;
5809 def.vd_ndx = 1;
5810 def.vd_cnt = 1;
5811 if (info->create_default_symver)
5812 {
5813 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5814 def.vd_next = sizeof (Elf_External_Verdef);
5815 }
5816 else
5817 {
5818 def.vd_aux = sizeof (Elf_External_Verdef);
5819 def.vd_next = (sizeof (Elf_External_Verdef)
5820 + sizeof (Elf_External_Verdaux));
5821 }
5822
5823 if (soname_indx != (bfd_size_type) -1)
5824 {
5825 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5826 soname_indx);
5827 def.vd_hash = bfd_elf_hash (soname);
5828 defaux.vda_name = soname_indx;
5829 name = soname;
5830 }
5831 else
5832 {
5833 bfd_size_type indx;
5834
5835 name = lbasename (output_bfd->filename);
5836 def.vd_hash = bfd_elf_hash (name);
5837 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5838 name, FALSE);
5839 if (indx == (bfd_size_type) -1)
5840 return FALSE;
5841 defaux.vda_name = indx;
5842 }
5843 defaux.vda_next = 0;
5844
5845 _bfd_elf_swap_verdef_out (output_bfd, &def,
5846 (Elf_External_Verdef *) p);
5847 p += sizeof (Elf_External_Verdef);
5848 if (info->create_default_symver)
5849 {
5850 /* Add a symbol representing this version. */
5851 bh = NULL;
5852 if (! (_bfd_generic_link_add_one_symbol
5853 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5854 0, NULL, FALSE,
5855 get_elf_backend_data (dynobj)->collect, &bh)))
5856 return FALSE;
5857 h = (struct elf_link_hash_entry *) bh;
5858 h->non_elf = 0;
5859 h->def_regular = 1;
5860 h->type = STT_OBJECT;
5861 h->verinfo.vertree = NULL;
5862
5863 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5864 return FALSE;
5865
5866 /* Create a duplicate of the base version with the same
5867 aux block, but different flags. */
5868 def.vd_flags = 0;
5869 def.vd_ndx = 2;
5870 def.vd_aux = sizeof (Elf_External_Verdef);
5871 if (verdefs)
5872 def.vd_next = (sizeof (Elf_External_Verdef)
5873 + sizeof (Elf_External_Verdaux));
5874 else
5875 def.vd_next = 0;
5876 _bfd_elf_swap_verdef_out (output_bfd, &def,
5877 (Elf_External_Verdef *) p);
5878 p += sizeof (Elf_External_Verdef);
5879 }
5880 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5881 (Elf_External_Verdaux *) p);
5882 p += sizeof (Elf_External_Verdaux);
5883
5884 for (t = verdefs; t != NULL; t = t->next)
5885 {
5886 unsigned int cdeps;
5887 struct bfd_elf_version_deps *n;
5888
5889 cdeps = 0;
5890 for (n = t->deps; n != NULL; n = n->next)
5891 ++cdeps;
5892
5893 /* Add a symbol representing this version. */
5894 bh = NULL;
5895 if (! (_bfd_generic_link_add_one_symbol
5896 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5897 0, NULL, FALSE,
5898 get_elf_backend_data (dynobj)->collect, &bh)))
5899 return FALSE;
5900 h = (struct elf_link_hash_entry *) bh;
5901 h->non_elf = 0;
5902 h->def_regular = 1;
5903 h->type = STT_OBJECT;
5904 h->verinfo.vertree = t;
5905
5906 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5907 return FALSE;
5908
5909 def.vd_version = VER_DEF_CURRENT;
5910 def.vd_flags = 0;
5911 if (t->globals.list == NULL
5912 && t->locals.list == NULL
5913 && ! t->used)
5914 def.vd_flags |= VER_FLG_WEAK;
5915 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5916 def.vd_cnt = cdeps + 1;
5917 def.vd_hash = bfd_elf_hash (t->name);
5918 def.vd_aux = sizeof (Elf_External_Verdef);
5919 def.vd_next = 0;
5920 if (t->next != NULL)
5921 def.vd_next = (sizeof (Elf_External_Verdef)
5922 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5923
5924 _bfd_elf_swap_verdef_out (output_bfd, &def,
5925 (Elf_External_Verdef *) p);
5926 p += sizeof (Elf_External_Verdef);
5927
5928 defaux.vda_name = h->dynstr_index;
5929 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5930 h->dynstr_index);
5931 defaux.vda_next = 0;
5932 if (t->deps != NULL)
5933 defaux.vda_next = sizeof (Elf_External_Verdaux);
5934 t->name_indx = defaux.vda_name;
5935
5936 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5937 (Elf_External_Verdaux *) p);
5938 p += sizeof (Elf_External_Verdaux);
5939
5940 for (n = t->deps; n != NULL; n = n->next)
5941 {
5942 if (n->version_needed == NULL)
5943 {
5944 /* This can happen if there was an error in the
5945 version script. */
5946 defaux.vda_name = 0;
5947 }
5948 else
5949 {
5950 defaux.vda_name = n->version_needed->name_indx;
5951 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5952 defaux.vda_name);
5953 }
5954 if (n->next == NULL)
5955 defaux.vda_next = 0;
5956 else
5957 defaux.vda_next = sizeof (Elf_External_Verdaux);
5958
5959 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5960 (Elf_External_Verdaux *) p);
5961 p += sizeof (Elf_External_Verdaux);
5962 }
5963 }
5964
5965 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5966 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5967 return FALSE;
5968
5969 elf_tdata (output_bfd)->cverdefs = cdefs;
5970 }
5971
5972 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5973 {
5974 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5975 return FALSE;
5976 }
5977 else if (info->flags & DF_BIND_NOW)
5978 {
5979 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5980 return FALSE;
5981 }
5982
5983 if (info->flags_1)
5984 {
5985 if (info->executable)
5986 info->flags_1 &= ~ (DF_1_INITFIRST
5987 | DF_1_NODELETE
5988 | DF_1_NOOPEN);
5989 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5990 return FALSE;
5991 }
5992
5993 /* Work out the size of the version reference section. */
5994
5995 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5996 BFD_ASSERT (s != NULL);
5997 {
5998 struct elf_find_verdep_info sinfo;
5999
6000 sinfo.output_bfd = output_bfd;
6001 sinfo.info = info;
6002 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
6003 if (sinfo.vers == 0)
6004 sinfo.vers = 1;
6005 sinfo.failed = FALSE;
6006
6007 elf_link_hash_traverse (elf_hash_table (info),
6008 _bfd_elf_link_find_version_dependencies,
6009 &sinfo);
6010
6011 if (elf_tdata (output_bfd)->verref == NULL)
6012 s->flags |= SEC_EXCLUDE;
6013 else
6014 {
6015 Elf_Internal_Verneed *t;
6016 unsigned int size;
6017 unsigned int crefs;
6018 bfd_byte *p;
6019
6020 /* Build the version definition section. */
6021 size = 0;
6022 crefs = 0;
6023 for (t = elf_tdata (output_bfd)->verref;
6024 t != NULL;
6025 t = t->vn_nextref)
6026 {
6027 Elf_Internal_Vernaux *a;
6028
6029 size += sizeof (Elf_External_Verneed);
6030 ++crefs;
6031 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6032 size += sizeof (Elf_External_Vernaux);
6033 }
6034
6035 s->size = size;
6036 s->contents = bfd_alloc (output_bfd, s->size);
6037 if (s->contents == NULL)
6038 return FALSE;
6039
6040 p = s->contents;
6041 for (t = elf_tdata (output_bfd)->verref;
6042 t != NULL;
6043 t = t->vn_nextref)
6044 {
6045 unsigned int caux;
6046 Elf_Internal_Vernaux *a;
6047 bfd_size_type indx;
6048
6049 caux = 0;
6050 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6051 ++caux;
6052
6053 t->vn_version = VER_NEED_CURRENT;
6054 t->vn_cnt = caux;
6055 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6056 elf_dt_name (t->vn_bfd) != NULL
6057 ? elf_dt_name (t->vn_bfd)
6058 : lbasename (t->vn_bfd->filename),
6059 FALSE);
6060 if (indx == (bfd_size_type) -1)
6061 return FALSE;
6062 t->vn_file = indx;
6063 t->vn_aux = sizeof (Elf_External_Verneed);
6064 if (t->vn_nextref == NULL)
6065 t->vn_next = 0;
6066 else
6067 t->vn_next = (sizeof (Elf_External_Verneed)
6068 + caux * sizeof (Elf_External_Vernaux));
6069
6070 _bfd_elf_swap_verneed_out (output_bfd, t,
6071 (Elf_External_Verneed *) p);
6072 p += sizeof (Elf_External_Verneed);
6073
6074 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
6075 {
6076 a->vna_hash = bfd_elf_hash (a->vna_nodename);
6077 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6078 a->vna_nodename, FALSE);
6079 if (indx == (bfd_size_type) -1)
6080 return FALSE;
6081 a->vna_name = indx;
6082 if (a->vna_nextptr == NULL)
6083 a->vna_next = 0;
6084 else
6085 a->vna_next = sizeof (Elf_External_Vernaux);
6086
6087 _bfd_elf_swap_vernaux_out (output_bfd, a,
6088 (Elf_External_Vernaux *) p);
6089 p += sizeof (Elf_External_Vernaux);
6090 }
6091 }
6092
6093 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
6094 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
6095 return FALSE;
6096
6097 elf_tdata (output_bfd)->cverrefs = crefs;
6098 }
6099 }
6100
6101 if ((elf_tdata (output_bfd)->cverrefs == 0
6102 && elf_tdata (output_bfd)->cverdefs == 0)
6103 || _bfd_elf_link_renumber_dynsyms (output_bfd, info,
6104 §ion_sym_count) == 0)
6105 {
6106 s = bfd_get_section_by_name (dynobj, ".gnu.version");
6107 s->flags |= SEC_EXCLUDE;
6108 }
6109 }
6110 return TRUE;
6111 }
6112
6113 /* Find the first non-excluded output section. We'll use its
6114 section symbol for some emitted relocs. */
6115 void
_bfd_elf_init_1_index_section(bfd * output_bfd,struct bfd_link_info * info)6116 _bfd_elf_init_1_index_section (bfd *output_bfd, struct bfd_link_info *info)
6117 {
6118 asection *s;
6119
6120 for (s = output_bfd->sections; s != NULL; s = s->next)
6121 if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
6122 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6123 {
6124 elf_hash_table (info)->text_index_section = s;
6125 break;
6126 }
6127 }
6128
6129 /* Find two non-excluded output sections, one for code, one for data.
6130 We'll use their section symbols for some emitted relocs. */
6131 void
_bfd_elf_init_2_index_sections(bfd * output_bfd,struct bfd_link_info * info)6132 _bfd_elf_init_2_index_sections (bfd *output_bfd, struct bfd_link_info *info)
6133 {
6134 asection *s;
6135
6136 for (s = output_bfd->sections; s != NULL; s = s->next)
6137 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY))
6138 == (SEC_ALLOC | SEC_READONLY))
6139 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6140 {
6141 elf_hash_table (info)->text_index_section = s;
6142 break;
6143 }
6144
6145 for (s = output_bfd->sections; s != NULL; s = s->next)
6146 if (((s->flags & (SEC_EXCLUDE | SEC_ALLOC | SEC_READONLY)) == SEC_ALLOC)
6147 && !_bfd_elf_link_omit_section_dynsym (output_bfd, info, s))
6148 {
6149 elf_hash_table (info)->data_index_section = s;
6150 break;
6151 }
6152
6153 if (elf_hash_table (info)->text_index_section == NULL)
6154 elf_hash_table (info)->text_index_section
6155 = elf_hash_table (info)->data_index_section;
6156 }
6157
6158 bfd_boolean
bfd_elf_size_dynsym_hash_dynstr(bfd * output_bfd,struct bfd_link_info * info)6159 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
6160 {
6161 const struct elf_backend_data *bed;
6162
6163 if (!is_elf_hash_table (info->hash))
6164 return TRUE;
6165
6166 bed = get_elf_backend_data (output_bfd);
6167 (*bed->elf_backend_init_index_section) (output_bfd, info);
6168
6169 if (elf_hash_table (info)->dynamic_sections_created)
6170 {
6171 bfd *dynobj;
6172 asection *s;
6173 bfd_size_type dynsymcount;
6174 unsigned long section_sym_count;
6175 unsigned int dtagcount;
6176
6177 dynobj = elf_hash_table (info)->dynobj;
6178
6179 /* Assign dynsym indicies. In a shared library we generate a
6180 section symbol for each output section, which come first.
6181 Next come all of the back-end allocated local dynamic syms,
6182 followed by the rest of the global symbols. */
6183
6184 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
6185 §ion_sym_count);
6186
6187 /* Work out the size of the symbol version section. */
6188 s = bfd_get_section_by_name (dynobj, ".gnu.version");
6189 BFD_ASSERT (s != NULL);
6190 if (dynsymcount != 0
6191 && (s->flags & SEC_EXCLUDE) == 0)
6192 {
6193 s->size = dynsymcount * sizeof (Elf_External_Versym);
6194 s->contents = bfd_zalloc (output_bfd, s->size);
6195 if (s->contents == NULL)
6196 return FALSE;
6197
6198 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
6199 return FALSE;
6200 }
6201
6202 /* Set the size of the .dynsym and .hash sections. We counted
6203 the number of dynamic symbols in elf_link_add_object_symbols.
6204 We will build the contents of .dynsym and .hash when we build
6205 the final symbol table, because until then we do not know the
6206 correct value to give the symbols. We built the .dynstr
6207 section as we went along in elf_link_add_object_symbols. */
6208 s = bfd_get_section_by_name (dynobj, ".dynsym");
6209 BFD_ASSERT (s != NULL);
6210 s->size = dynsymcount * bed->s->sizeof_sym;
6211
6212 if (dynsymcount != 0)
6213 {
6214 s->contents = bfd_alloc (output_bfd, s->size);
6215 if (s->contents == NULL)
6216 return FALSE;
6217
6218 /* The first entry in .dynsym is a dummy symbol.
6219 Clear all the section syms, in case we don't output them all. */
6220 ++section_sym_count;
6221 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
6222 }
6223
6224 elf_hash_table (info)->bucketcount = 0;
6225
6226 /* Compute the size of the hashing table. As a side effect this
6227 computes the hash values for all the names we export. */
6228 if (info->emit_hash)
6229 {
6230 unsigned long int *hashcodes;
6231 unsigned long int *hashcodesp;
6232 bfd_size_type amt;
6233 unsigned long int nsyms;
6234 size_t bucketcount;
6235 size_t hash_entry_size;
6236
6237 /* Compute the hash values for all exported symbols. At the same
6238 time store the values in an array so that we could use them for
6239 optimizations. */
6240 amt = dynsymcount * sizeof (unsigned long int);
6241 hashcodes = bfd_malloc (amt);
6242 if (hashcodes == NULL)
6243 return FALSE;
6244 hashcodesp = hashcodes;
6245
6246 /* Put all hash values in HASHCODES. */
6247 elf_link_hash_traverse (elf_hash_table (info),
6248 elf_collect_hash_codes, &hashcodesp);
6249
6250 nsyms = hashcodesp - hashcodes;
6251 bucketcount
6252 = compute_bucket_count (info, hashcodes, nsyms, 0);
6253 free (hashcodes);
6254
6255 if (bucketcount == 0)
6256 return FALSE;
6257
6258 elf_hash_table (info)->bucketcount = bucketcount;
6259
6260 s = bfd_get_section_by_name (dynobj, ".hash");
6261 BFD_ASSERT (s != NULL);
6262 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
6263 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
6264 s->contents = bfd_zalloc (output_bfd, s->size);
6265 if (s->contents == NULL)
6266 return FALSE;
6267
6268 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
6269 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
6270 s->contents + hash_entry_size);
6271 }
6272
6273 if (info->emit_gnu_hash)
6274 {
6275 size_t i, cnt;
6276 unsigned char *contents;
6277 struct collect_gnu_hash_codes cinfo;
6278 bfd_size_type amt;
6279 size_t bucketcount;
6280
6281 memset (&cinfo, 0, sizeof (cinfo));
6282
6283 /* Compute the hash values for all exported symbols. At the same
6284 time store the values in an array so that we could use them for
6285 optimizations. */
6286 amt = dynsymcount * 2 * sizeof (unsigned long int);
6287 cinfo.hashcodes = bfd_malloc (amt);
6288 if (cinfo.hashcodes == NULL)
6289 return FALSE;
6290
6291 cinfo.hashval = cinfo.hashcodes + dynsymcount;
6292 cinfo.min_dynindx = -1;
6293 cinfo.output_bfd = output_bfd;
6294 cinfo.bed = bed;
6295
6296 /* Put all hash values in HASHCODES. */
6297 elf_link_hash_traverse (elf_hash_table (info),
6298 elf_collect_gnu_hash_codes, &cinfo);
6299
6300 bucketcount
6301 = compute_bucket_count (info, cinfo.hashcodes, cinfo.nsyms, 1);
6302
6303 if (bucketcount == 0)
6304 {
6305 free (cinfo.hashcodes);
6306 return FALSE;
6307 }
6308
6309 s = bfd_get_section_by_name (dynobj, ".gnu.hash");
6310 BFD_ASSERT (s != NULL);
6311
6312 if (cinfo.nsyms == 0)
6313 {
6314 /* Empty .gnu.hash section is special. */
6315 BFD_ASSERT (cinfo.min_dynindx == -1);
6316 free (cinfo.hashcodes);
6317 s->size = 5 * 4 + bed->s->arch_size / 8;
6318 contents = bfd_zalloc (output_bfd, s->size);
6319 if (contents == NULL)
6320 return FALSE;
6321 s->contents = contents;
6322 /* 1 empty bucket. */
6323 bfd_put_32 (output_bfd, 1, contents);
6324 /* SYMIDX above the special symbol 0. */
6325 bfd_put_32 (output_bfd, 1, contents + 4);
6326 /* Just one word for bitmask. */
6327 bfd_put_32 (output_bfd, 1, contents + 8);
6328 /* Only hash fn bloom filter. */
6329 bfd_put_32 (output_bfd, 0, contents + 12);
6330 /* No hashes are valid - empty bitmask. */
6331 bfd_put (bed->s->arch_size, output_bfd, 0, contents + 16);
6332 /* No hashes in the only bucket. */
6333 bfd_put_32 (output_bfd, 0,
6334 contents + 16 + bed->s->arch_size / 8);
6335 }
6336 else
6337 {
6338 unsigned long int maskwords, maskbitslog2;
6339 BFD_ASSERT (cinfo.min_dynindx != -1);
6340
6341 maskbitslog2 = bfd_log2 (cinfo.nsyms) + 1;
6342 if (maskbitslog2 < 3)
6343 maskbitslog2 = 5;
6344 else if ((1 << (maskbitslog2 - 2)) & cinfo.nsyms)
6345 maskbitslog2 = maskbitslog2 + 3;
6346 else
6347 maskbitslog2 = maskbitslog2 + 2;
6348 if (bed->s->arch_size == 64)
6349 {
6350 if (maskbitslog2 == 5)
6351 maskbitslog2 = 6;
6352 cinfo.shift1 = 6;
6353 }
6354 else
6355 cinfo.shift1 = 5;
6356 cinfo.mask = (1 << cinfo.shift1) - 1;
6357 cinfo.shift2 = maskbitslog2;
6358 cinfo.maskbits = 1 << maskbitslog2;
6359 maskwords = 1 << (maskbitslog2 - cinfo.shift1);
6360 amt = bucketcount * sizeof (unsigned long int) * 2;
6361 amt += maskwords * sizeof (bfd_vma);
6362 cinfo.bitmask = bfd_malloc (amt);
6363 if (cinfo.bitmask == NULL)
6364 {
6365 free (cinfo.hashcodes);
6366 return FALSE;
6367 }
6368
6369 cinfo.counts = (void *) (cinfo.bitmask + maskwords);
6370 cinfo.indx = cinfo.counts + bucketcount;
6371 cinfo.symindx = dynsymcount - cinfo.nsyms;
6372 memset (cinfo.bitmask, 0, maskwords * sizeof (bfd_vma));
6373
6374 /* Determine how often each hash bucket is used. */
6375 memset (cinfo.counts, 0, bucketcount * sizeof (cinfo.counts[0]));
6376 for (i = 0; i < cinfo.nsyms; ++i)
6377 ++cinfo.counts[cinfo.hashcodes[i] % bucketcount];
6378
6379 for (i = 0, cnt = cinfo.symindx; i < bucketcount; ++i)
6380 if (cinfo.counts[i] != 0)
6381 {
6382 cinfo.indx[i] = cnt;
6383 cnt += cinfo.counts[i];
6384 }
6385 BFD_ASSERT (cnt == dynsymcount);
6386 cinfo.bucketcount = bucketcount;
6387 cinfo.local_indx = cinfo.min_dynindx;
6388
6389 s->size = (4 + bucketcount + cinfo.nsyms) * 4;
6390 s->size += cinfo.maskbits / 8;
6391 contents = bfd_zalloc (output_bfd, s->size);
6392 if (contents == NULL)
6393 {
6394 free (cinfo.bitmask);
6395 free (cinfo.hashcodes);
6396 return FALSE;
6397 }
6398
6399 s->contents = contents;
6400 bfd_put_32 (output_bfd, bucketcount, contents);
6401 bfd_put_32 (output_bfd, cinfo.symindx, contents + 4);
6402 bfd_put_32 (output_bfd, maskwords, contents + 8);
6403 bfd_put_32 (output_bfd, cinfo.shift2, contents + 12);
6404 contents += 16 + cinfo.maskbits / 8;
6405
6406 for (i = 0; i < bucketcount; ++i)
6407 {
6408 if (cinfo.counts[i] == 0)
6409 bfd_put_32 (output_bfd, 0, contents);
6410 else
6411 bfd_put_32 (output_bfd, cinfo.indx[i], contents);
6412 contents += 4;
6413 }
6414
6415 cinfo.contents = contents;
6416
6417 /* Renumber dynamic symbols, populate .gnu.hash section. */
6418 elf_link_hash_traverse (elf_hash_table (info),
6419 elf_renumber_gnu_hash_syms, &cinfo);
6420
6421 contents = s->contents + 16;
6422 for (i = 0; i < maskwords; ++i)
6423 {
6424 bfd_put (bed->s->arch_size, output_bfd, cinfo.bitmask[i],
6425 contents);
6426 contents += bed->s->arch_size / 8;
6427 }
6428
6429 free (cinfo.bitmask);
6430 free (cinfo.hashcodes);
6431 }
6432 }
6433
6434 s = bfd_get_section_by_name (dynobj, ".dynstr");
6435 BFD_ASSERT (s != NULL);
6436
6437 elf_finalize_dynstr (output_bfd, info);
6438
6439 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
6440
6441 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
6442 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
6443 return FALSE;
6444 }
6445
6446 return TRUE;
6447 }
6448
6449 /* Final phase of ELF linker. */
6450
6451 /* A structure we use to avoid passing large numbers of arguments. */
6452
6453 struct elf_final_link_info
6454 {
6455 /* General link information. */
6456 struct bfd_link_info *info;
6457 /* Output BFD. */
6458 bfd *output_bfd;
6459 /* Symbol string table. */
6460 struct bfd_strtab_hash *symstrtab;
6461 /* .dynsym section. */
6462 asection *dynsym_sec;
6463 /* .hash section. */
6464 asection *hash_sec;
6465 /* symbol version section (.gnu.version). */
6466 asection *symver_sec;
6467 /* Buffer large enough to hold contents of any section. */
6468 bfd_byte *contents;
6469 /* Buffer large enough to hold external relocs of any section. */
6470 void *external_relocs;
6471 /* Buffer large enough to hold internal relocs of any section. */
6472 Elf_Internal_Rela *internal_relocs;
6473 /* Buffer large enough to hold external local symbols of any input
6474 BFD. */
6475 bfd_byte *external_syms;
6476 /* And a buffer for symbol section indices. */
6477 Elf_External_Sym_Shndx *locsym_shndx;
6478 /* Buffer large enough to hold internal local symbols of any input
6479 BFD. */
6480 Elf_Internal_Sym *internal_syms;
6481 /* Array large enough to hold a symbol index for each local symbol
6482 of any input BFD. */
6483 long *indices;
6484 /* Array large enough to hold a section pointer for each local
6485 symbol of any input BFD. */
6486 asection **sections;
6487 /* Buffer to hold swapped out symbols. */
6488 bfd_byte *symbuf;
6489 /* And one for symbol section indices. */
6490 Elf_External_Sym_Shndx *symshndxbuf;
6491 /* Number of swapped out symbols in buffer. */
6492 size_t symbuf_count;
6493 /* Number of symbols which fit in symbuf. */
6494 size_t symbuf_size;
6495 /* And same for symshndxbuf. */
6496 size_t shndxbuf_size;
6497 };
6498
6499 /* This struct is used to pass information to elf_link_output_extsym. */
6500
6501 struct elf_outext_info
6502 {
6503 bfd_boolean failed;
6504 bfd_boolean localsyms;
6505 struct elf_final_link_info *finfo;
6506 };
6507
6508
6509 /* Support for evaluating a complex relocation.
6510
6511 Complex relocations are generalized, self-describing relocations. The
6512 implementation of them consists of two parts: complex symbols, and the
6513 relocations themselves.
6514
6515 The relocations are use a reserved elf-wide relocation type code (R_RELC
6516 external / BFD_RELOC_RELC internal) and an encoding of relocation field
6517 information (start bit, end bit, word width, etc) into the addend. This
6518 information is extracted from CGEN-generated operand tables within gas.
6519
6520 Complex symbols are mangled symbols (BSF_RELC external / STT_RELC
6521 internal) representing prefix-notation expressions, including but not
6522 limited to those sorts of expressions normally encoded as addends in the
6523 addend field. The symbol mangling format is:
6524
6525 <node> := <literal>
6526 | <unary-operator> ':' <node>
6527 | <binary-operator> ':' <node> ':' <node>
6528 ;
6529
6530 <literal> := 's' <digits=N> ':' <N character symbol name>
6531 | 'S' <digits=N> ':' <N character section name>
6532 | '#' <hexdigits>
6533 ;
6534
6535 <binary-operator> := as in C
6536 <unary-operator> := as in C, plus "0-" for unambiguous negation. */
6537
6538 static void
set_symbol_value(bfd * bfd_with_globals,struct elf_final_link_info * finfo,int symidx,bfd_vma val)6539 set_symbol_value (bfd * bfd_with_globals,
6540 struct elf_final_link_info * finfo,
6541 int symidx,
6542 bfd_vma val)
6543 {
6544 bfd_boolean is_local;
6545 Elf_Internal_Sym * sym;
6546 struct elf_link_hash_entry ** sym_hashes;
6547 struct elf_link_hash_entry * h;
6548
6549 sym_hashes = elf_sym_hashes (bfd_with_globals);
6550 sym = finfo->internal_syms + symidx;
6551 is_local = ELF_ST_BIND(sym->st_info) == STB_LOCAL;
6552
6553 if (is_local)
6554 {
6555 /* It is a local symbol: move it to the
6556 "absolute" section and give it a value. */
6557 sym->st_shndx = SHN_ABS;
6558 sym->st_value = val;
6559 }
6560 else
6561 {
6562 /* It is a global symbol: set its link type
6563 to "defined" and give it a value. */
6564 h = sym_hashes [symidx];
6565 while (h->root.type == bfd_link_hash_indirect
6566 || h->root.type == bfd_link_hash_warning)
6567 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6568 h->root.type = bfd_link_hash_defined;
6569 h->root.u.def.value = val;
6570 h->root.u.def.section = bfd_abs_section_ptr;
6571 }
6572 }
6573
6574 static bfd_boolean
resolve_symbol(const char * name,bfd * input_bfd,struct elf_final_link_info * finfo,bfd_vma * result,size_t locsymcount)6575 resolve_symbol (const char * name,
6576 bfd * input_bfd,
6577 struct elf_final_link_info * finfo,
6578 bfd_vma * result,
6579 size_t locsymcount)
6580 {
6581 Elf_Internal_Sym * sym;
6582 struct bfd_link_hash_entry * global_entry;
6583 const char * candidate = NULL;
6584 Elf_Internal_Shdr * symtab_hdr;
6585 asection * sec = NULL;
6586 size_t i;
6587
6588 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
6589
6590 for (i = 0; i < locsymcount; ++ i)
6591 {
6592 sym = finfo->internal_syms + i;
6593 sec = finfo->sections [i];
6594
6595 if (ELF_ST_BIND (sym->st_info) != STB_LOCAL)
6596 continue;
6597
6598 candidate = bfd_elf_string_from_elf_section (input_bfd,
6599 symtab_hdr->sh_link,
6600 sym->st_name);
6601 #ifdef DEBUG
6602 printf ("Comparing string: '%s' vs. '%s' = 0x%x\n",
6603 name, candidate, (unsigned int)sym->st_value);
6604 #endif
6605 if (candidate && strcmp (candidate, name) == 0)
6606 {
6607 * result = sym->st_value;
6608
6609 if (sym->st_shndx > SHN_UNDEF &&
6610 sym->st_shndx < SHN_LORESERVE)
6611 {
6612 #ifdef DEBUG
6613 printf ("adjusting for sec '%s' @ 0x%x + 0x%x\n",
6614 sec->output_section->name,
6615 (unsigned int)sec->output_section->vma,
6616 (unsigned int)sec->output_offset);
6617 #endif
6618 * result += sec->output_offset + sec->output_section->vma;
6619 }
6620 #ifdef DEBUG
6621 printf ("Found symbol with effective value %8.8x\n", (unsigned int)* result);
6622 #endif
6623 return TRUE;
6624 }
6625 }
6626
6627 /* Hmm, haven't found it yet. perhaps it is a global. */
6628 global_entry = bfd_link_hash_lookup (finfo->info->hash, name, FALSE, FALSE, TRUE);
6629 if (!global_entry)
6630 return FALSE;
6631
6632 if (global_entry->type == bfd_link_hash_defined
6633 || global_entry->type == bfd_link_hash_defweak)
6634 {
6635 * result = global_entry->u.def.value
6636 + global_entry->u.def.section->output_section->vma
6637 + global_entry->u.def.section->output_offset;
6638 #ifdef DEBUG
6639 printf ("Found GLOBAL symbol '%s' with value %8.8x\n",
6640 global_entry->root.string, (unsigned int)*result);
6641 #endif
6642 return TRUE;
6643 }
6644
6645 if (global_entry->type == bfd_link_hash_common)
6646 {
6647 *result = global_entry->u.def.value +
6648 bfd_com_section_ptr->output_section->vma +
6649 bfd_com_section_ptr->output_offset;
6650 #ifdef DEBUG
6651 printf ("Found COMMON symbol '%s' with value %8.8x\n",
6652 global_entry->root.string, (unsigned int)*result);
6653 #endif
6654 return TRUE;
6655 }
6656
6657 return FALSE;
6658 }
6659
6660 static bfd_boolean
resolve_section(const char * name,asection * sections,bfd_vma * result)6661 resolve_section (const char * name,
6662 asection * sections,
6663 bfd_vma * result)
6664 {
6665 asection * curr;
6666 unsigned int len;
6667
6668 for (curr = sections; curr; curr = curr->next)
6669 if (strcmp (curr->name, name) == 0)
6670 {
6671 *result = curr->vma;
6672 return TRUE;
6673 }
6674
6675 /* Hmm. still haven't found it. try pseudo-section names. */
6676 for (curr = sections; curr; curr = curr->next)
6677 {
6678 len = strlen (curr->name);
6679 if (len > strlen (name))
6680 continue;
6681
6682 if (strncmp (curr->name, name, len) == 0)
6683 {
6684 if (strncmp (".end", name + len, 4) == 0)
6685 {
6686 *result = curr->vma + curr->size;
6687 return TRUE;
6688 }
6689
6690 /* Insert more pseudo-section names here, if you like. */
6691 }
6692 }
6693
6694 return FALSE;
6695 }
6696
6697 static void
undefined_reference(const char * reftype,const char * name)6698 undefined_reference (const char * reftype,
6699 const char * name)
6700 {
6701 _bfd_error_handler (_("undefined %s reference in complex symbol: %s"), reftype, name);
6702 }
6703
6704 static bfd_boolean
eval_symbol(bfd_vma * result,char * sym,char ** advanced,bfd * input_bfd,struct elf_final_link_info * finfo,bfd_vma addr,bfd_vma section_offset,size_t locsymcount,int signed_p)6705 eval_symbol (bfd_vma * result,
6706 char * sym,
6707 char ** advanced,
6708 bfd * input_bfd,
6709 struct elf_final_link_info * finfo,
6710 bfd_vma addr,
6711 bfd_vma section_offset,
6712 size_t locsymcount,
6713 int signed_p)
6714 {
6715 int len;
6716 int symlen;
6717 bfd_vma a;
6718 bfd_vma b;
6719 const int bufsz = 4096;
6720 char symbuf [bufsz];
6721 const char * symend;
6722 bfd_boolean symbol_is_section = FALSE;
6723
6724 len = strlen (sym);
6725 symend = sym + len;
6726
6727 if (len < 1 || len > bufsz)
6728 {
6729 bfd_set_error (bfd_error_invalid_operation);
6730 return FALSE;
6731 }
6732
6733 switch (* sym)
6734 {
6735 case '.':
6736 * result = addr + section_offset;
6737 * advanced = sym + 1;
6738 return TRUE;
6739
6740 case '#':
6741 ++ sym;
6742 * result = strtoul (sym, advanced, 16);
6743 return TRUE;
6744
6745 case 'S':
6746 symbol_is_section = TRUE;
6747 case 's':
6748 ++ sym;
6749 symlen = strtol (sym, &sym, 10);
6750 ++ sym; /* Skip the trailing ':'. */
6751
6752 if ((symend < sym) || ((symlen + 1) > bufsz))
6753 {
6754 bfd_set_error (bfd_error_invalid_operation);
6755 return FALSE;
6756 }
6757
6758 memcpy (symbuf, sym, symlen);
6759 symbuf [symlen] = '\0';
6760 * advanced = sym + symlen;
6761
6762 /* Is it always possible, with complex symbols, that gas "mis-guessed"
6763 the symbol as a section, or vice-versa. so we're pretty liberal in our
6764 interpretation here; section means "try section first", not "must be a
6765 section", and likewise with symbol. */
6766
6767 if (symbol_is_section)
6768 {
6769 if ((resolve_section (symbuf, finfo->output_bfd->sections, result) != TRUE)
6770 && (resolve_symbol (symbuf, input_bfd, finfo, result, locsymcount) != TRUE))
6771 {
6772 undefined_reference ("section", symbuf);
6773 return FALSE;
6774 }
6775 }
6776 else
6777 {
6778 if ((resolve_symbol (symbuf, input_bfd, finfo, result, locsymcount) != TRUE)
6779 && (resolve_section (symbuf, finfo->output_bfd->sections,
6780 result) != TRUE))
6781 {
6782 undefined_reference ("symbol", symbuf);
6783 return FALSE;
6784 }
6785 }
6786
6787 return TRUE;
6788
6789 /* All that remains are operators. */
6790
6791 #define UNARY_OP(op) \
6792 if (strncmp (sym, #op, strlen (#op)) == 0) \
6793 { \
6794 sym += strlen (#op); \
6795 if (* sym == ':') \
6796 ++ sym; \
6797 if (eval_symbol (& a, sym, & sym, input_bfd, finfo, addr, \
6798 section_offset, locsymcount, signed_p) \
6799 != TRUE) \
6800 return FALSE; \
6801 if (signed_p) \
6802 * result = op ((signed)a); \
6803 else \
6804 * result = op a; \
6805 * advanced = sym; \
6806 return TRUE; \
6807 }
6808
6809 #define BINARY_OP(op) \
6810 if (strncmp (sym, #op, strlen (#op)) == 0) \
6811 { \
6812 sym += strlen (#op); \
6813 if (* sym == ':') \
6814 ++ sym; \
6815 if (eval_symbol (& a, sym, & sym, input_bfd, finfo, addr, \
6816 section_offset, locsymcount, signed_p) \
6817 != TRUE) \
6818 return FALSE; \
6819 ++ sym; \
6820 if (eval_symbol (& b, sym, & sym, input_bfd, finfo, addr, \
6821 section_offset, locsymcount, signed_p) \
6822 != TRUE) \
6823 return FALSE; \
6824 if (signed_p) \
6825 * result = ((signed) a) op ((signed) b); \
6826 else \
6827 * result = a op b; \
6828 * advanced = sym; \
6829 return TRUE; \
6830 }
6831
6832 default:
6833 UNARY_OP (0-);
6834 BINARY_OP (<<);
6835 BINARY_OP (>>);
6836 BINARY_OP (==);
6837 BINARY_OP (!=);
6838 BINARY_OP (<=);
6839 BINARY_OP (>=);
6840 BINARY_OP (&&);
6841 BINARY_OP (||);
6842 UNARY_OP (~);
6843 UNARY_OP (!);
6844 BINARY_OP (*);
6845 BINARY_OP (/);
6846 BINARY_OP (%);
6847 BINARY_OP (^);
6848 BINARY_OP (|);
6849 BINARY_OP (&);
6850 BINARY_OP (+);
6851 BINARY_OP (-);
6852 BINARY_OP (<);
6853 BINARY_OP (>);
6854 #undef UNARY_OP
6855 #undef BINARY_OP
6856 _bfd_error_handler (_("unknown operator '%c' in complex symbol"), * sym);
6857 bfd_set_error (bfd_error_invalid_operation);
6858 return FALSE;
6859 }
6860 }
6861
6862 /* Entry point to evaluator, called from elf_link_input_bfd. */
6863
6864 static bfd_boolean
evaluate_complex_relocation_symbols(bfd * input_bfd,struct elf_final_link_info * finfo,size_t locsymcount)6865 evaluate_complex_relocation_symbols (bfd * input_bfd,
6866 struct elf_final_link_info * finfo,
6867 size_t locsymcount)
6868 {
6869 const struct elf_backend_data * bed;
6870 Elf_Internal_Shdr * symtab_hdr;
6871 struct elf_link_hash_entry ** sym_hashes;
6872 asection * reloc_sec;
6873 bfd_boolean result = TRUE;
6874
6875 /* For each section, we're going to check and see if it has any
6876 complex relocations, and we're going to evaluate any of them
6877 we can. */
6878
6879 if (finfo->info->relocatable)
6880 return TRUE;
6881
6882 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
6883 sym_hashes = elf_sym_hashes (input_bfd);
6884 bed = get_elf_backend_data (input_bfd);
6885
6886 for (reloc_sec = input_bfd->sections; reloc_sec; reloc_sec = reloc_sec->next)
6887 {
6888 Elf_Internal_Rela * internal_relocs;
6889 unsigned long i;
6890
6891 /* This section was omitted from the link. */
6892 if (! reloc_sec->linker_mark)
6893 continue;
6894
6895 /* Only process sections containing relocs. */
6896 if ((reloc_sec->flags & SEC_RELOC) == 0)
6897 continue;
6898
6899 if (reloc_sec->reloc_count == 0)
6900 continue;
6901
6902 /* Read in the relocs for this section. */
6903 internal_relocs
6904 = _bfd_elf_link_read_relocs (input_bfd, reloc_sec, NULL,
6905 (Elf_Internal_Rela *) NULL,
6906 FALSE);
6907 if (internal_relocs == NULL)
6908 continue;
6909
6910 for (i = reloc_sec->reloc_count; i--;)
6911 {
6912 Elf_Internal_Rela * rel;
6913 char * sym_name;
6914 bfd_vma index;
6915 Elf_Internal_Sym * sym;
6916 bfd_vma result;
6917 bfd_vma section_offset;
6918 bfd_vma addr;
6919 int signed_p = 0;
6920
6921 rel = internal_relocs + i;
6922 section_offset = reloc_sec->output_section->vma
6923 + reloc_sec->output_offset;
6924 addr = rel->r_offset;
6925
6926 index = ELF32_R_SYM (rel->r_info);
6927 if (bed->s->arch_size == 64)
6928 index >>= 24;
6929
6930 if (index == STN_UNDEF)
6931 continue;
6932
6933 if (index < locsymcount)
6934 {
6935 /* The symbol is local. */
6936 sym = finfo->internal_syms + index;
6937
6938 /* We're only processing STT_RELC or STT_SRELC type symbols. */
6939 if ((ELF_ST_TYPE (sym->st_info) != STT_RELC) &&
6940 (ELF_ST_TYPE (sym->st_info) != STT_SRELC))
6941 continue;
6942
6943 sym_name = bfd_elf_string_from_elf_section
6944 (input_bfd, symtab_hdr->sh_link, sym->st_name);
6945
6946 signed_p = (ELF_ST_TYPE (sym->st_info) == STT_SRELC);
6947 }
6948 else
6949 {
6950 /* The symbol is global. */
6951 struct elf_link_hash_entry * h;
6952
6953 if (elf_bad_symtab (input_bfd))
6954 continue;
6955
6956 h = sym_hashes [index - locsymcount];
6957 while ( h->root.type == bfd_link_hash_indirect
6958 || h->root.type == bfd_link_hash_warning)
6959 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6960
6961 if (h->type != STT_RELC && h->type != STT_SRELC)
6962 continue;
6963
6964 signed_p = (h->type == STT_SRELC);
6965 sym_name = (char *) h->root.root.string;
6966 }
6967 #ifdef DEBUG
6968 printf ("Encountered a complex symbol!");
6969 printf (" (input_bfd %s, section %s, reloc %ld\n",
6970 input_bfd->filename, reloc_sec->name, i);
6971 printf (" symbol: idx %8.8lx, name %s\n",
6972 index, sym_name);
6973 printf (" reloc : info %8.8lx, addr %8.8lx\n",
6974 rel->r_info, addr);
6975 printf (" Evaluating '%s' ...\n ", sym_name);
6976 #endif
6977 if (eval_symbol (& result, sym_name, & sym_name, input_bfd,
6978 finfo, addr, section_offset, locsymcount,
6979 signed_p))
6980 /* Symbol evaluated OK. Update to absolute value. */
6981 set_symbol_value (input_bfd, finfo, index, result);
6982
6983 else
6984 result = FALSE;
6985 }
6986
6987 if (internal_relocs != elf_section_data (reloc_sec)->relocs)
6988 free (internal_relocs);
6989 }
6990
6991 /* If nothing went wrong, then we adjusted
6992 everything we wanted to adjust. */
6993 return result;
6994 }
6995
6996 static void
put_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_vma x,bfd_byte * location)6997 put_value (bfd_vma size,
6998 unsigned long chunksz,
6999 bfd * input_bfd,
7000 bfd_vma x,
7001 bfd_byte * location)
7002 {
7003 location += (size - chunksz);
7004
7005 for (; size; size -= chunksz, location -= chunksz, x >>= (chunksz * 8))
7006 {
7007 switch (chunksz)
7008 {
7009 default:
7010 case 0:
7011 abort ();
7012 case 1:
7013 bfd_put_8 (input_bfd, x, location);
7014 break;
7015 case 2:
7016 bfd_put_16 (input_bfd, x, location);
7017 break;
7018 case 4:
7019 bfd_put_32 (input_bfd, x, location);
7020 break;
7021 case 8:
7022 #ifdef BFD64
7023 bfd_put_64 (input_bfd, x, location);
7024 #else
7025 abort ();
7026 #endif
7027 break;
7028 }
7029 }
7030 }
7031
7032 static bfd_vma
get_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_byte * location)7033 get_value (bfd_vma size,
7034 unsigned long chunksz,
7035 bfd * input_bfd,
7036 bfd_byte * location)
7037 {
7038 bfd_vma x = 0;
7039
7040 for (; size; size -= chunksz, location += chunksz)
7041 {
7042 switch (chunksz)
7043 {
7044 default:
7045 case 0:
7046 abort ();
7047 case 1:
7048 x = (x << (8 * chunksz)) | bfd_get_8 (input_bfd, location);
7049 break;
7050 case 2:
7051 x = (x << (8 * chunksz)) | bfd_get_16 (input_bfd, location);
7052 break;
7053 case 4:
7054 x = (x << (8 * chunksz)) | bfd_get_32 (input_bfd, location);
7055 break;
7056 case 8:
7057 #ifdef BFD64
7058 x = (x << (8 * chunksz)) | bfd_get_64 (input_bfd, location);
7059 #else
7060 abort ();
7061 #endif
7062 break;
7063 }
7064 }
7065 return x;
7066 }
7067
7068 static void
decode_complex_addend(unsigned long * start,unsigned long * oplen,unsigned long * len,unsigned long * wordsz,unsigned long * chunksz,unsigned long * lsb0_p,unsigned long * signed_p,unsigned long * trunc_p,unsigned long encoded)7069 decode_complex_addend
7070 (unsigned long * start, /* in bits */
7071 unsigned long * oplen, /* in bits */
7072 unsigned long * len, /* in bits */
7073 unsigned long * wordsz, /* in bytes */
7074 unsigned long * chunksz, /* in bytes */
7075 unsigned long * lsb0_p,
7076 unsigned long * signed_p,
7077 unsigned long * trunc_p,
7078 unsigned long encoded)
7079 {
7080 * start = encoded & 0x3F;
7081 * len = (encoded >> 6) & 0x3F;
7082 * oplen = (encoded >> 12) & 0x3F;
7083 * wordsz = (encoded >> 18) & 0xF;
7084 * chunksz = (encoded >> 22) & 0xF;
7085 * lsb0_p = (encoded >> 27) & 1;
7086 * signed_p = (encoded >> 28) & 1;
7087 * trunc_p = (encoded >> 29) & 1;
7088 }
7089
7090 void
bfd_elf_perform_complex_relocation(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * rel,Elf_Internal_Sym * local_syms,asection ** local_sections)7091 bfd_elf_perform_complex_relocation
7092 (bfd * output_bfd ATTRIBUTE_UNUSED,
7093 struct bfd_link_info * info,
7094 bfd * input_bfd,
7095 asection * input_section,
7096 bfd_byte * contents,
7097 Elf_Internal_Rela * rel,
7098 Elf_Internal_Sym * local_syms,
7099 asection ** local_sections)
7100 {
7101 const struct elf_backend_data * bed;
7102 Elf_Internal_Shdr * symtab_hdr;
7103 asection * sec;
7104 bfd_vma relocation = 0, shift, x;
7105 bfd_vma r_symndx;
7106 bfd_vma mask;
7107 unsigned long start, oplen, len, wordsz,
7108 chunksz, lsb0_p, signed_p, trunc_p;
7109
7110 /* Perform this reloc, since it is complex.
7111 (this is not to say that it necessarily refers to a complex
7112 symbol; merely that it is a self-describing CGEN based reloc.
7113 i.e. the addend has the complete reloc information (bit start, end,
7114 word size, etc) encoded within it.). */
7115 r_symndx = ELF32_R_SYM (rel->r_info);
7116 bed = get_elf_backend_data (input_bfd);
7117 if (bed->s->arch_size == 64)
7118 r_symndx >>= 24;
7119
7120 #ifdef DEBUG
7121 printf ("Performing complex relocation %ld...\n", r_symndx);
7122 #endif
7123
7124 symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
7125 if (r_symndx < symtab_hdr->sh_info)
7126 {
7127 /* The symbol is local. */
7128 Elf_Internal_Sym * sym;
7129
7130 sym = local_syms + r_symndx;
7131 sec = local_sections [r_symndx];
7132 relocation = sym->st_value;
7133 if (sym->st_shndx > SHN_UNDEF &&
7134 sym->st_shndx < SHN_LORESERVE)
7135 relocation += (sec->output_offset +
7136 sec->output_section->vma);
7137 }
7138 else
7139 {
7140 /* The symbol is global. */
7141 struct elf_link_hash_entry **sym_hashes;
7142 struct elf_link_hash_entry * h;
7143
7144 sym_hashes = elf_sym_hashes (input_bfd);
7145 h = sym_hashes [r_symndx];
7146
7147 while (h->root.type == bfd_link_hash_indirect
7148 || h->root.type == bfd_link_hash_warning)
7149 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7150
7151 if (h->root.type == bfd_link_hash_defined
7152 || h->root.type == bfd_link_hash_defweak)
7153 {
7154 sec = h->root.u.def.section;
7155 relocation = h->root.u.def.value;
7156
7157 if (! bfd_is_abs_section (sec))
7158 relocation += (sec->output_section->vma
7159 + sec->output_offset);
7160 }
7161 if (h->root.type == bfd_link_hash_undefined
7162 && !((*info->callbacks->undefined_symbol)
7163 (info, h->root.root.string, input_bfd,
7164 input_section, rel->r_offset,
7165 info->unresolved_syms_in_objects == RM_GENERATE_ERROR
7166 || ELF_ST_VISIBILITY (h->other))))
7167 return;
7168 }
7169
7170 decode_complex_addend (& start, & oplen, & len, & wordsz,
7171 & chunksz, & lsb0_p, & signed_p,
7172 & trunc_p, rel->r_addend);
7173
7174 mask = (((1L << (len - 1)) - 1) << 1) | 1;
7175
7176 if (lsb0_p)
7177 shift = (start + 1) - len;
7178 else
7179 shift = (8 * wordsz) - (start + len);
7180
7181 x = get_value (wordsz, chunksz, input_bfd, contents + rel->r_offset);
7182
7183 #ifdef DEBUG
7184 printf ("Doing complex reloc: "
7185 "lsb0? %ld, signed? %ld, trunc? %ld, wordsz %ld, "
7186 "chunksz %ld, start %ld, len %ld, oplen %ld\n"
7187 " dest: %8.8lx, mask: %8.8lx, reloc: %8.8lx\n",
7188 lsb0_p, signed_p, trunc_p, wordsz, chunksz, start, len,
7189 oplen, x, mask, relocation);
7190 #endif
7191
7192 if (! trunc_p)
7193 {
7194 /* Now do an overflow check. */
7195 if (bfd_check_overflow ((signed_p ?
7196 complain_overflow_signed :
7197 complain_overflow_unsigned),
7198 len, 0, (8 * wordsz),
7199 relocation) == bfd_reloc_overflow)
7200 (*_bfd_error_handler)
7201 ("%s (%s + 0x%lx): relocation overflow: 0x%lx %sdoes not fit "
7202 "within 0x%lx",
7203 input_bfd->filename, input_section->name, rel->r_offset,
7204 relocation, (signed_p ? "(signed) " : ""), mask);
7205 }
7206
7207 /* Do the deed. */
7208 x = (x & ~(mask << shift)) | ((relocation & mask) << shift);
7209
7210 #ifdef DEBUG
7211 printf (" relocation: %8.8lx\n"
7212 " shifted mask: %8.8lx\n"
7213 " shifted/masked reloc: %8.8lx\n"
7214 " result: %8.8lx\n",
7215 relocation, (mask << shift),
7216 ((relocation & mask) << shift), x);
7217 #endif
7218 put_value (wordsz, chunksz, input_bfd, x, contents + rel->r_offset);
7219 }
7220
7221 /* When performing a relocatable link, the input relocations are
7222 preserved. But, if they reference global symbols, the indices
7223 referenced must be updated. Update all the relocations in
7224 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
7225
7226 static void
elf_link_adjust_relocs(bfd * abfd,Elf_Internal_Shdr * rel_hdr,unsigned int count,struct elf_link_hash_entry ** rel_hash)7227 elf_link_adjust_relocs (bfd *abfd,
7228 Elf_Internal_Shdr *rel_hdr,
7229 unsigned int count,
7230 struct elf_link_hash_entry **rel_hash)
7231 {
7232 unsigned int i;
7233 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7234 bfd_byte *erela;
7235 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
7236 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
7237 bfd_vma r_type_mask;
7238 int r_sym_shift;
7239
7240 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
7241 {
7242 swap_in = bed->s->swap_reloc_in;
7243 swap_out = bed->s->swap_reloc_out;
7244 }
7245 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
7246 {
7247 swap_in = bed->s->swap_reloca_in;
7248 swap_out = bed->s->swap_reloca_out;
7249 }
7250 else
7251 abort ();
7252
7253 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
7254 abort ();
7255
7256 if (bed->s->arch_size == 32)
7257 {
7258 r_type_mask = 0xff;
7259 r_sym_shift = 8;
7260 }
7261 else
7262 {
7263 r_type_mask = 0xffffffff;
7264 r_sym_shift = 32;
7265 }
7266
7267 erela = rel_hdr->contents;
7268 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
7269 {
7270 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
7271 unsigned int j;
7272
7273 if (*rel_hash == NULL)
7274 continue;
7275
7276 BFD_ASSERT ((*rel_hash)->indx >= 0);
7277
7278 (*swap_in) (abfd, erela, irela);
7279 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
7280 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
7281 | (irela[j].r_info & r_type_mask));
7282 (*swap_out) (abfd, irela, erela);
7283 }
7284 }
7285
7286 struct elf_link_sort_rela
7287 {
7288 union {
7289 bfd_vma offset;
7290 bfd_vma sym_mask;
7291 } u;
7292 enum elf_reloc_type_class type;
7293 /* We use this as an array of size int_rels_per_ext_rel. */
7294 Elf_Internal_Rela rela[1];
7295 };
7296
7297 static int
elf_link_sort_cmp1(const void * A,const void * B)7298 elf_link_sort_cmp1 (const void *A, const void *B)
7299 {
7300 const struct elf_link_sort_rela *a = A;
7301 const struct elf_link_sort_rela *b = B;
7302 int relativea, relativeb;
7303
7304 relativea = a->type == reloc_class_relative;
7305 relativeb = b->type == reloc_class_relative;
7306
7307 if (relativea < relativeb)
7308 return 1;
7309 if (relativea > relativeb)
7310 return -1;
7311 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
7312 return -1;
7313 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
7314 return 1;
7315 if (a->rela->r_offset < b->rela->r_offset)
7316 return -1;
7317 if (a->rela->r_offset > b->rela->r_offset)
7318 return 1;
7319 return 0;
7320 }
7321
7322 static int
elf_link_sort_cmp2(const void * A,const void * B)7323 elf_link_sort_cmp2 (const void *A, const void *B)
7324 {
7325 const struct elf_link_sort_rela *a = A;
7326 const struct elf_link_sort_rela *b = B;
7327 int copya, copyb;
7328
7329 if (a->u.offset < b->u.offset)
7330 return -1;
7331 if (a->u.offset > b->u.offset)
7332 return 1;
7333 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
7334 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
7335 if (copya < copyb)
7336 return -1;
7337 if (copya > copyb)
7338 return 1;
7339 if (a->rela->r_offset < b->rela->r_offset)
7340 return -1;
7341 if (a->rela->r_offset > b->rela->r_offset)
7342 return 1;
7343 return 0;
7344 }
7345
7346 static size_t
elf_link_sort_relocs(bfd * abfd,struct bfd_link_info * info,asection ** psec)7347 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
7348 {
7349 asection *dynamic_relocs;
7350 asection *rela_dyn;
7351 asection *rel_dyn;
7352 bfd_size_type count, size;
7353 size_t i, ret, sort_elt, ext_size;
7354 bfd_byte *sort, *s_non_relative, *p;
7355 struct elf_link_sort_rela *sq;
7356 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7357 int i2e = bed->s->int_rels_per_ext_rel;
7358 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
7359 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
7360 struct bfd_link_order *lo;
7361 bfd_vma r_sym_mask;
7362 bfd_boolean use_rela;
7363
7364 /* Find a dynamic reloc section. */
7365 rela_dyn = bfd_get_section_by_name (abfd, ".rela.dyn");
7366 rel_dyn = bfd_get_section_by_name (abfd, ".rel.dyn");
7367 if (rela_dyn != NULL && rela_dyn->size > 0
7368 && rel_dyn != NULL && rel_dyn->size > 0)
7369 {
7370 bfd_boolean use_rela_initialised = FALSE;
7371
7372 /* This is just here to stop gcc from complaining.
7373 It's initialization checking code is not perfect. */
7374 use_rela = TRUE;
7375
7376 /* Both sections are present. Examine the sizes
7377 of the indirect sections to help us choose. */
7378 for (lo = rela_dyn->map_head.link_order; lo != NULL; lo = lo->next)
7379 if (lo->type == bfd_indirect_link_order)
7380 {
7381 asection *o = lo->u.indirect.section;
7382
7383 if ((o->size % bed->s->sizeof_rela) == 0)
7384 {
7385 if ((o->size % bed->s->sizeof_rel) == 0)
7386 /* Section size is divisible by both rel and rela sizes.
7387 It is of no help to us. */
7388 ;
7389 else
7390 {
7391 /* Section size is only divisible by rela. */
7392 if (use_rela_initialised && (use_rela == FALSE))
7393 {
7394 _bfd_error_handler
7395 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
7396 bfd_set_error (bfd_error_invalid_operation);
7397 return 0;
7398 }
7399 else
7400 {
7401 use_rela = TRUE;
7402 use_rela_initialised = TRUE;
7403 }
7404 }
7405 }
7406 else if ((o->size % bed->s->sizeof_rel) == 0)
7407 {
7408 /* Section size is only divisible by rel. */
7409 if (use_rela_initialised && (use_rela == TRUE))
7410 {
7411 _bfd_error_handler
7412 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
7413 bfd_set_error (bfd_error_invalid_operation);
7414 return 0;
7415 }
7416 else
7417 {
7418 use_rela = FALSE;
7419 use_rela_initialised = TRUE;
7420 }
7421 }
7422 else
7423 {
7424 /* The section size is not divisible by either - something is wrong. */
7425 _bfd_error_handler
7426 (_("%B: Unable to sort relocs - they are of an unknown size"), abfd);
7427 bfd_set_error (bfd_error_invalid_operation);
7428 return 0;
7429 }
7430 }
7431
7432 for (lo = rel_dyn->map_head.link_order; lo != NULL; lo = lo->next)
7433 if (lo->type == bfd_indirect_link_order)
7434 {
7435 asection *o = lo->u.indirect.section;
7436
7437 if ((o->size % bed->s->sizeof_rela) == 0)
7438 {
7439 if ((o->size % bed->s->sizeof_rel) == 0)
7440 /* Section size is divisible by both rel and rela sizes.
7441 It is of no help to us. */
7442 ;
7443 else
7444 {
7445 /* Section size is only divisible by rela. */
7446 if (use_rela_initialised && (use_rela == FALSE))
7447 {
7448 _bfd_error_handler
7449 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
7450 bfd_set_error (bfd_error_invalid_operation);
7451 return 0;
7452 }
7453 else
7454 {
7455 use_rela = TRUE;
7456 use_rela_initialised = TRUE;
7457 }
7458 }
7459 }
7460 else if ((o->size % bed->s->sizeof_rel) == 0)
7461 {
7462 /* Section size is only divisible by rel. */
7463 if (use_rela_initialised && (use_rela == TRUE))
7464 {
7465 _bfd_error_handler
7466 (_("%B: Unable to sort relocs - they are in more than one size"), abfd);
7467 bfd_set_error (bfd_error_invalid_operation);
7468 return 0;
7469 }
7470 else
7471 {
7472 use_rela = FALSE;
7473 use_rela_initialised = TRUE;
7474 }
7475 }
7476 else
7477 {
7478 /* The section size is not divisible by either - something is wrong. */
7479 _bfd_error_handler
7480 (_("%B: Unable to sort relocs - they are of an unknown size"), abfd);
7481 bfd_set_error (bfd_error_invalid_operation);
7482 return 0;
7483 }
7484 }
7485
7486 if (! use_rela_initialised)
7487 /* Make a guess. */
7488 use_rela = TRUE;
7489 }
7490 else if (rela_dyn != NULL && rela_dyn->size > 0)
7491 use_rela = TRUE;
7492 else if (rel_dyn != NULL && rel_dyn->size > 0)
7493 use_rela = FALSE;
7494 else
7495 return 0;
7496
7497 if (use_rela)
7498 {
7499 dynamic_relocs = rela_dyn;
7500 ext_size = bed->s->sizeof_rela;
7501 swap_in = bed->s->swap_reloca_in;
7502 swap_out = bed->s->swap_reloca_out;
7503 }
7504 else
7505 {
7506 dynamic_relocs = rel_dyn;
7507 ext_size = bed->s->sizeof_rel;
7508 swap_in = bed->s->swap_reloc_in;
7509 swap_out = bed->s->swap_reloc_out;
7510 }
7511
7512 size = 0;
7513 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
7514 if (lo->type == bfd_indirect_link_order)
7515 size += lo->u.indirect.section->size;
7516
7517 if (size != dynamic_relocs->size)
7518 return 0;
7519
7520 sort_elt = (sizeof (struct elf_link_sort_rela)
7521 + (i2e - 1) * sizeof (Elf_Internal_Rela));
7522
7523 count = dynamic_relocs->size / ext_size;
7524 sort = bfd_zmalloc (sort_elt * count);
7525
7526 if (sort == NULL)
7527 {
7528 (*info->callbacks->warning)
7529 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
7530 return 0;
7531 }
7532
7533 if (bed->s->arch_size == 32)
7534 r_sym_mask = ~(bfd_vma) 0xff;
7535 else
7536 r_sym_mask = ~(bfd_vma) 0xffffffff;
7537
7538 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
7539 if (lo->type == bfd_indirect_link_order)
7540 {
7541 bfd_byte *erel, *erelend;
7542 asection *o = lo->u.indirect.section;
7543
7544 if (o->contents == NULL && o->size != 0)
7545 {
7546 /* This is a reloc section that is being handled as a normal
7547 section. See bfd_section_from_shdr. We can't combine
7548 relocs in this case. */
7549 free (sort);
7550 return 0;
7551 }
7552 erel = o->contents;
7553 erelend = o->contents + o->size;
7554 p = sort + o->output_offset / ext_size * sort_elt;
7555
7556 while (erel < erelend)
7557 {
7558 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
7559
7560 (*swap_in) (abfd, erel, s->rela);
7561 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
7562 s->u.sym_mask = r_sym_mask;
7563 p += sort_elt;
7564 erel += ext_size;
7565 }
7566 }
7567
7568 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
7569
7570 for (i = 0, p = sort; i < count; i++, p += sort_elt)
7571 {
7572 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
7573 if (s->type != reloc_class_relative)
7574 break;
7575 }
7576 ret = i;
7577 s_non_relative = p;
7578
7579 sq = (struct elf_link_sort_rela *) s_non_relative;
7580 for (; i < count; i++, p += sort_elt)
7581 {
7582 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
7583 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
7584 sq = sp;
7585 sp->u.offset = sq->rela->r_offset;
7586 }
7587
7588 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
7589
7590 for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
7591 if (lo->type == bfd_indirect_link_order)
7592 {
7593 bfd_byte *erel, *erelend;
7594 asection *o = lo->u.indirect.section;
7595
7596 erel = o->contents;
7597 erelend = o->contents + o->size;
7598 p = sort + o->output_offset / ext_size * sort_elt;
7599 while (erel < erelend)
7600 {
7601 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
7602 (*swap_out) (abfd, s->rela, erel);
7603 p += sort_elt;
7604 erel += ext_size;
7605 }
7606 }
7607
7608 free (sort);
7609 *psec = dynamic_relocs;
7610 return ret;
7611 }
7612
7613 /* Flush the output symbols to the file. */
7614
7615 static bfd_boolean
elf_link_flush_output_syms(struct elf_final_link_info * finfo,const struct elf_backend_data * bed)7616 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
7617 const struct elf_backend_data *bed)
7618 {
7619 if (finfo->symbuf_count > 0)
7620 {
7621 Elf_Internal_Shdr *hdr;
7622 file_ptr pos;
7623 bfd_size_type amt;
7624
7625 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
7626 pos = hdr->sh_offset + hdr->sh_size;
7627 amt = finfo->symbuf_count * bed->s->sizeof_sym;
7628 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
7629 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
7630 return FALSE;
7631
7632 hdr->sh_size += amt;
7633 finfo->symbuf_count = 0;
7634 }
7635
7636 return TRUE;
7637 }
7638
7639 /* Add a symbol to the output symbol table. */
7640
7641 static bfd_boolean
elf_link_output_sym(struct elf_final_link_info * finfo,const char * name,Elf_Internal_Sym * elfsym,asection * input_sec,struct elf_link_hash_entry * h)7642 elf_link_output_sym (struct elf_final_link_info *finfo,
7643 const char *name,
7644 Elf_Internal_Sym *elfsym,
7645 asection *input_sec,
7646 struct elf_link_hash_entry *h)
7647 {
7648 bfd_byte *dest;
7649 Elf_External_Sym_Shndx *destshndx;
7650 bfd_boolean (*output_symbol_hook)
7651 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
7652 struct elf_link_hash_entry *);
7653 const struct elf_backend_data *bed;
7654
7655 bed = get_elf_backend_data (finfo->output_bfd);
7656 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
7657 if (output_symbol_hook != NULL)
7658 {
7659 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
7660 return FALSE;
7661 }
7662
7663 if (name == NULL || *name == '\0')
7664 elfsym->st_name = 0;
7665 else if (input_sec->flags & SEC_EXCLUDE)
7666 elfsym->st_name = 0;
7667 else
7668 {
7669 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
7670 name, TRUE, FALSE);
7671 if (elfsym->st_name == (unsigned long) -1)
7672 return FALSE;
7673 }
7674
7675 if (finfo->symbuf_count >= finfo->symbuf_size)
7676 {
7677 if (! elf_link_flush_output_syms (finfo, bed))
7678 return FALSE;
7679 }
7680
7681 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
7682 destshndx = finfo->symshndxbuf;
7683 if (destshndx != NULL)
7684 {
7685 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
7686 {
7687 bfd_size_type amt;
7688
7689 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
7690 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
7691 if (destshndx == NULL)
7692 return FALSE;
7693 memset ((char *) destshndx + amt, 0, amt);
7694 finfo->shndxbuf_size *= 2;
7695 }
7696 destshndx += bfd_get_symcount (finfo->output_bfd);
7697 }
7698
7699 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
7700 finfo->symbuf_count += 1;
7701 bfd_get_symcount (finfo->output_bfd) += 1;
7702
7703 return TRUE;
7704 }
7705
7706 /* Return TRUE if the dynamic symbol SYM in ABFD is supported. */
7707
7708 static bfd_boolean
check_dynsym(bfd * abfd,Elf_Internal_Sym * sym)7709 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
7710 {
7711 if (sym->st_shndx > SHN_HIRESERVE)
7712 {
7713 /* The gABI doesn't support dynamic symbols in output sections
7714 beyond 64k. */
7715 (*_bfd_error_handler)
7716 (_("%B: Too many sections: %d (>= %d)"),
7717 abfd, bfd_count_sections (abfd), SHN_LORESERVE);
7718 bfd_set_error (bfd_error_nonrepresentable_section);
7719 return FALSE;
7720 }
7721 return TRUE;
7722 }
7723
7724 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
7725 allowing an unsatisfied unversioned symbol in the DSO to match a
7726 versioned symbol that would normally require an explicit version.
7727 We also handle the case that a DSO references a hidden symbol
7728 which may be satisfied by a versioned symbol in another DSO. */
7729
7730 static bfd_boolean
elf_link_check_versioned_symbol(struct bfd_link_info * info,const struct elf_backend_data * bed,struct elf_link_hash_entry * h)7731 elf_link_check_versioned_symbol (struct bfd_link_info *info,
7732 const struct elf_backend_data *bed,
7733 struct elf_link_hash_entry *h)
7734 {
7735 bfd *abfd;
7736 struct elf_link_loaded_list *loaded;
7737
7738 if (!is_elf_hash_table (info->hash))
7739 return FALSE;
7740
7741 switch (h->root.type)
7742 {
7743 default:
7744 abfd = NULL;
7745 break;
7746
7747 case bfd_link_hash_undefined:
7748 case bfd_link_hash_undefweak:
7749 abfd = h->root.u.undef.abfd;
7750 if ((abfd->flags & DYNAMIC) == 0
7751 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
7752 return FALSE;
7753 break;
7754
7755 case bfd_link_hash_defined:
7756 case bfd_link_hash_defweak:
7757 abfd = h->root.u.def.section->owner;
7758 break;
7759
7760 case bfd_link_hash_common:
7761 abfd = h->root.u.c.p->section->owner;
7762 break;
7763 }
7764 BFD_ASSERT (abfd != NULL);
7765
7766 for (loaded = elf_hash_table (info)->loaded;
7767 loaded != NULL;
7768 loaded = loaded->next)
7769 {
7770 bfd *input;
7771 Elf_Internal_Shdr *hdr;
7772 bfd_size_type symcount;
7773 bfd_size_type extsymcount;
7774 bfd_size_type extsymoff;
7775 Elf_Internal_Shdr *versymhdr;
7776 Elf_Internal_Sym *isym;
7777 Elf_Internal_Sym *isymend;
7778 Elf_Internal_Sym *isymbuf;
7779 Elf_External_Versym *ever;
7780 Elf_External_Versym *extversym;
7781
7782 input = loaded->abfd;
7783
7784 /* We check each DSO for a possible hidden versioned definition. */
7785 if (input == abfd
7786 || (input->flags & DYNAMIC) == 0
7787 || elf_dynversym (input) == 0)
7788 continue;
7789
7790 hdr = &elf_tdata (input)->dynsymtab_hdr;
7791
7792 symcount = hdr->sh_size / bed->s->sizeof_sym;
7793 if (elf_bad_symtab (input))
7794 {
7795 extsymcount = symcount;
7796 extsymoff = 0;
7797 }
7798 else
7799 {
7800 extsymcount = symcount - hdr->sh_info;
7801 extsymoff = hdr->sh_info;
7802 }
7803
7804 if (extsymcount == 0)
7805 continue;
7806
7807 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
7808 NULL, NULL, NULL);
7809 if (isymbuf == NULL)
7810 return FALSE;
7811
7812 /* Read in any version definitions. */
7813 versymhdr = &elf_tdata (input)->dynversym_hdr;
7814 extversym = bfd_malloc (versymhdr->sh_size);
7815 if (extversym == NULL)
7816 goto error_ret;
7817
7818 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
7819 || (bfd_bread (extversym, versymhdr->sh_size, input)
7820 != versymhdr->sh_size))
7821 {
7822 free (extversym);
7823 error_ret:
7824 free (isymbuf);
7825 return FALSE;
7826 }
7827
7828 ever = extversym + extsymoff;
7829 isymend = isymbuf + extsymcount;
7830 for (isym = isymbuf; isym < isymend; isym++, ever++)
7831 {
7832 const char *name;
7833 Elf_Internal_Versym iver;
7834 unsigned short version_index;
7835
7836 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
7837 || isym->st_shndx == SHN_UNDEF)
7838 continue;
7839
7840 name = bfd_elf_string_from_elf_section (input,
7841 hdr->sh_link,
7842 isym->st_name);
7843 if (strcmp (name, h->root.root.string) != 0)
7844 continue;
7845
7846 _bfd_elf_swap_versym_in (input, ever, &iver);
7847
7848 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
7849 {
7850 /* If we have a non-hidden versioned sym, then it should
7851 have provided a definition for the undefined sym. */
7852 abort ();
7853 }
7854
7855 version_index = iver.vs_vers & VERSYM_VERSION;
7856 if (version_index == 1 || version_index == 2)
7857 {
7858 /* This is the base or first version. We can use it. */
7859 free (extversym);
7860 free (isymbuf);
7861 return TRUE;
7862 }
7863 }
7864
7865 free (extversym);
7866 free (isymbuf);
7867 }
7868
7869 return FALSE;
7870 }
7871
7872 /* Add an external symbol to the symbol table. This is called from
7873 the hash table traversal routine. When generating a shared object,
7874 we go through the symbol table twice. The first time we output
7875 anything that might have been forced to local scope in a version
7876 script. The second time we output the symbols that are still
7877 global symbols. */
7878
7879 static bfd_boolean
elf_link_output_extsym(struct elf_link_hash_entry * h,void * data)7880 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
7881 {
7882 struct elf_outext_info *eoinfo = data;
7883 struct elf_final_link_info *finfo = eoinfo->finfo;
7884 bfd_boolean strip;
7885 Elf_Internal_Sym sym;
7886 asection *input_sec;
7887 const struct elf_backend_data *bed;
7888
7889 if (h->root.type == bfd_link_hash_warning)
7890 {
7891 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7892 if (h->root.type == bfd_link_hash_new)
7893 return TRUE;
7894 }
7895
7896 /* Decide whether to output this symbol in this pass. */
7897 if (eoinfo->localsyms)
7898 {
7899 if (!h->forced_local)
7900 return TRUE;
7901 }
7902 else
7903 {
7904 if (h->forced_local)
7905 return TRUE;
7906 }
7907
7908 bed = get_elf_backend_data (finfo->output_bfd);
7909
7910 if (h->root.type == bfd_link_hash_undefined)
7911 {
7912 /* If we have an undefined symbol reference here then it must have
7913 come from a shared library that is being linked in. (Undefined
7914 references in regular files have already been handled). */
7915 bfd_boolean ignore_undef = FALSE;
7916
7917 /* Some symbols may be special in that the fact that they're
7918 undefined can be safely ignored - let backend determine that. */
7919 if (bed->elf_backend_ignore_undef_symbol)
7920 ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
7921
7922 /* If we are reporting errors for this situation then do so now. */
7923 if (ignore_undef == FALSE
7924 && h->ref_dynamic
7925 && ! h->ref_regular
7926 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
7927 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
7928 {
7929 if (! (finfo->info->callbacks->undefined_symbol
7930 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
7931 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
7932 {
7933 eoinfo->failed = TRUE;
7934 return FALSE;
7935 }
7936 }
7937 }
7938
7939 /* We should also warn if a forced local symbol is referenced from
7940 shared libraries. */
7941 if (! finfo->info->relocatable
7942 && (! finfo->info->shared)
7943 && h->forced_local
7944 && h->ref_dynamic
7945 && !h->dynamic_def
7946 && !h->dynamic_weak
7947 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
7948 {
7949 (*_bfd_error_handler)
7950 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
7951 finfo->output_bfd,
7952 h->root.u.def.section == bfd_abs_section_ptr
7953 ? finfo->output_bfd : h->root.u.def.section->owner,
7954 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
7955 ? "internal"
7956 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
7957 ? "hidden" : "local",
7958 h->root.root.string);
7959 eoinfo->failed = TRUE;
7960 return FALSE;
7961 }
7962
7963 /* We don't want to output symbols that have never been mentioned by
7964 a regular file, or that we have been told to strip. However, if
7965 h->indx is set to -2, the symbol is used by a reloc and we must
7966 output it. */
7967 if (h->indx == -2)
7968 strip = FALSE;
7969 else if ((h->def_dynamic
7970 || h->ref_dynamic
7971 || h->root.type == bfd_link_hash_new)
7972 && !h->def_regular
7973 && !h->ref_regular)
7974 strip = TRUE;
7975 else if (finfo->info->strip == strip_all)
7976 strip = TRUE;
7977 else if (finfo->info->strip == strip_some
7978 && bfd_hash_lookup (finfo->info->keep_hash,
7979 h->root.root.string, FALSE, FALSE) == NULL)
7980 strip = TRUE;
7981 else if (finfo->info->strip_discarded
7982 && (h->root.type == bfd_link_hash_defined
7983 || h->root.type == bfd_link_hash_defweak)
7984 && elf_discarded_section (h->root.u.def.section))
7985 strip = TRUE;
7986 else
7987 strip = FALSE;
7988
7989 /* If we're stripping it, and it's not a dynamic symbol, there's
7990 nothing else to do unless it is a forced local symbol. */
7991 if (strip
7992 && h->dynindx == -1
7993 && !h->forced_local)
7994 return TRUE;
7995
7996 sym.st_value = 0;
7997 sym.st_size = h->size;
7998 sym.st_other = h->other;
7999 if (h->forced_local)
8000 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
8001 else if (h->root.type == bfd_link_hash_undefweak
8002 || h->root.type == bfd_link_hash_defweak)
8003 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
8004 else
8005 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
8006
8007 switch (h->root.type)
8008 {
8009 default:
8010 case bfd_link_hash_new:
8011 case bfd_link_hash_warning:
8012 abort ();
8013 return FALSE;
8014
8015 case bfd_link_hash_undefined:
8016 case bfd_link_hash_undefweak:
8017 input_sec = bfd_und_section_ptr;
8018 sym.st_shndx = SHN_UNDEF;
8019 break;
8020
8021 case bfd_link_hash_defined:
8022 case bfd_link_hash_defweak:
8023 {
8024 input_sec = h->root.u.def.section;
8025 if (input_sec->output_section != NULL)
8026 {
8027 sym.st_shndx =
8028 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
8029 input_sec->output_section);
8030 if (sym.st_shndx == SHN_BAD)
8031 {
8032 (*_bfd_error_handler)
8033 (_("%B: could not find output section %A for input section %A"),
8034 finfo->output_bfd, input_sec->output_section, input_sec);
8035 eoinfo->failed = TRUE;
8036 return FALSE;
8037 }
8038
8039 /* ELF symbols in relocatable files are section relative,
8040 but in nonrelocatable files they are virtual
8041 addresses. */
8042 sym.st_value = h->root.u.def.value + input_sec->output_offset;
8043 if (! finfo->info->relocatable)
8044 {
8045 sym.st_value += input_sec->output_section->vma;
8046 if (h->type == STT_TLS)
8047 {
8048 /* STT_TLS symbols are relative to PT_TLS segment
8049 base. */
8050 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
8051 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
8052 }
8053 }
8054 }
8055 else
8056 {
8057 BFD_ASSERT (input_sec->owner == NULL
8058 || (input_sec->owner->flags & DYNAMIC) != 0);
8059 sym.st_shndx = SHN_UNDEF;
8060 input_sec = bfd_und_section_ptr;
8061 }
8062 }
8063 break;
8064
8065 case bfd_link_hash_common:
8066 input_sec = h->root.u.c.p->section;
8067 sym.st_shndx = bed->common_section_index (input_sec);
8068 sym.st_value = 1 << h->root.u.c.p->alignment_power;
8069 break;
8070
8071 case bfd_link_hash_indirect:
8072 /* These symbols are created by symbol versioning. They point
8073 to the decorated version of the name. For example, if the
8074 symbol foo@@GNU_1.2 is the default, which should be used when
8075 foo is used with no version, then we add an indirect symbol
8076 foo which points to foo@@GNU_1.2. We ignore these symbols,
8077 since the indirected symbol is already in the hash table. */
8078 return TRUE;
8079 }
8080
8081 /* Give the processor backend a chance to tweak the symbol value,
8082 and also to finish up anything that needs to be done for this
8083 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
8084 forced local syms when non-shared is due to a historical quirk. */
8085 if ((h->dynindx != -1
8086 || h->forced_local)
8087 && ((finfo->info->shared
8088 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
8089 || h->root.type != bfd_link_hash_undefweak))
8090 || !h->forced_local)
8091 && elf_hash_table (finfo->info)->dynamic_sections_created)
8092 {
8093 if (! ((*bed->elf_backend_finish_dynamic_symbol)
8094 (finfo->output_bfd, finfo->info, h, &sym)))
8095 {
8096 eoinfo->failed = TRUE;
8097 return FALSE;
8098 }
8099 }
8100
8101 /* If we are marking the symbol as undefined, and there are no
8102 non-weak references to this symbol from a regular object, then
8103 mark the symbol as weak undefined; if there are non-weak
8104 references, mark the symbol as strong. We can't do this earlier,
8105 because it might not be marked as undefined until the
8106 finish_dynamic_symbol routine gets through with it. */
8107 if (sym.st_shndx == SHN_UNDEF
8108 && h->ref_regular
8109 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
8110 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
8111 {
8112 int bindtype;
8113
8114 if (h->ref_regular_nonweak)
8115 bindtype = STB_GLOBAL;
8116 else
8117 bindtype = STB_WEAK;
8118 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
8119 }
8120
8121 /* If a non-weak symbol with non-default visibility is not defined
8122 locally, it is a fatal error. */
8123 if (! finfo->info->relocatable
8124 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
8125 && ELF_ST_BIND (sym.st_info) != STB_WEAK
8126 && h->root.type == bfd_link_hash_undefined
8127 && !h->def_regular)
8128 {
8129 (*_bfd_error_handler)
8130 (_("%B: %s symbol `%s' isn't defined"),
8131 finfo->output_bfd,
8132 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
8133 ? "protected"
8134 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
8135 ? "internal" : "hidden",
8136 h->root.root.string);
8137 eoinfo->failed = TRUE;
8138 return FALSE;
8139 }
8140
8141 /* If this symbol should be put in the .dynsym section, then put it
8142 there now. We already know the symbol index. We also fill in
8143 the entry in the .hash section. */
8144 if (h->dynindx != -1
8145 && elf_hash_table (finfo->info)->dynamic_sections_created)
8146 {
8147 bfd_byte *esym;
8148
8149 sym.st_name = h->dynstr_index;
8150 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
8151 if (! check_dynsym (finfo->output_bfd, &sym))
8152 {
8153 eoinfo->failed = TRUE;
8154 return FALSE;
8155 }
8156 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
8157
8158 if (finfo->hash_sec != NULL)
8159 {
8160 size_t hash_entry_size;
8161 bfd_byte *bucketpos;
8162 bfd_vma chain;
8163 size_t bucketcount;
8164 size_t bucket;
8165
8166 bucketcount = elf_hash_table (finfo->info)->bucketcount;
8167 bucket = h->u.elf_hash_value % bucketcount;
8168
8169 hash_entry_size
8170 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
8171 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
8172 + (bucket + 2) * hash_entry_size);
8173 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
8174 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
8175 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
8176 ((bfd_byte *) finfo->hash_sec->contents
8177 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
8178 }
8179
8180 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
8181 {
8182 Elf_Internal_Versym iversym;
8183 Elf_External_Versym *eversym;
8184
8185 if (!h->def_regular)
8186 {
8187 if (h->verinfo.verdef == NULL)
8188 iversym.vs_vers = 0;
8189 else
8190 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
8191 }
8192 else
8193 {
8194 if (h->verinfo.vertree == NULL)
8195 iversym.vs_vers = 1;
8196 else
8197 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
8198 if (finfo->info->create_default_symver)
8199 iversym.vs_vers++;
8200 }
8201
8202 if (h->hidden)
8203 iversym.vs_vers |= VERSYM_HIDDEN;
8204
8205 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
8206 eversym += h->dynindx;
8207 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
8208 }
8209 }
8210
8211 /* If we're stripping it, then it was just a dynamic symbol, and
8212 there's nothing else to do. */
8213 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
8214 return TRUE;
8215
8216 h->indx = bfd_get_symcount (finfo->output_bfd);
8217
8218 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
8219 {
8220 eoinfo->failed = TRUE;
8221 return FALSE;
8222 }
8223
8224 return TRUE;
8225 }
8226
8227 /* Return TRUE if special handling is done for relocs in SEC against
8228 symbols defined in discarded sections. */
8229
8230 static bfd_boolean
elf_section_ignore_discarded_relocs(asection * sec)8231 elf_section_ignore_discarded_relocs (asection *sec)
8232 {
8233 const struct elf_backend_data *bed;
8234
8235 switch (sec->sec_info_type)
8236 {
8237 case ELF_INFO_TYPE_STABS:
8238 case ELF_INFO_TYPE_EH_FRAME:
8239 return TRUE;
8240 default:
8241 break;
8242 }
8243
8244 bed = get_elf_backend_data (sec->owner);
8245 if (bed->elf_backend_ignore_discarded_relocs != NULL
8246 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
8247 return TRUE;
8248
8249 return FALSE;
8250 }
8251
8252 /* Return a mask saying how ld should treat relocations in SEC against
8253 symbols defined in discarded sections. If this function returns
8254 COMPLAIN set, ld will issue a warning message. If this function
8255 returns PRETEND set, and the discarded section was link-once and the
8256 same size as the kept link-once section, ld will pretend that the
8257 symbol was actually defined in the kept section. Otherwise ld will
8258 zero the reloc (at least that is the intent, but some cooperation by
8259 the target dependent code is needed, particularly for REL targets). */
8260
8261 unsigned int
_bfd_elf_default_action_discarded(asection * sec)8262 _bfd_elf_default_action_discarded (asection *sec)
8263 {
8264 if (sec->flags & SEC_DEBUGGING)
8265 return PRETEND;
8266
8267 if (strcmp (".eh_frame", sec->name) == 0)
8268 return 0;
8269
8270 if (strcmp (".gcc_except_table", sec->name) == 0)
8271 return 0;
8272
8273 return COMPLAIN | PRETEND;
8274 }
8275
8276 /* Find a match between a section and a member of a section group. */
8277
8278 static asection *
match_group_member(asection * sec,asection * group,struct bfd_link_info * info)8279 match_group_member (asection *sec, asection *group,
8280 struct bfd_link_info *info)
8281 {
8282 asection *first = elf_next_in_group (group);
8283 asection *s = first;
8284
8285 while (s != NULL)
8286 {
8287 if (bfd_elf_match_symbols_in_sections (s, sec, info))
8288 return s;
8289
8290 s = elf_next_in_group (s);
8291 if (s == first)
8292 break;
8293 }
8294
8295 return NULL;
8296 }
8297
8298 /* Check if the kept section of a discarded section SEC can be used
8299 to replace it. Return the replacement if it is OK. Otherwise return
8300 NULL. */
8301
8302 asection *
_bfd_elf_check_kept_section(asection * sec,struct bfd_link_info * info)8303 _bfd_elf_check_kept_section (asection *sec, struct bfd_link_info *info)
8304 {
8305 asection *kept;
8306
8307 kept = sec->kept_section;
8308 if (kept != NULL)
8309 {
8310 if ((kept->flags & SEC_GROUP) != 0)
8311 kept = match_group_member (sec, kept, info);
8312 if (kept != NULL && sec->size != kept->size)
8313 kept = NULL;
8314 sec->kept_section = kept;
8315 }
8316 return kept;
8317 }
8318
8319 /* Link an input file into the linker output file. This function
8320 handles all the sections and relocations of the input file at once.
8321 This is so that we only have to read the local symbols once, and
8322 don't have to keep them in memory. */
8323
8324 static bfd_boolean
elf_link_input_bfd(struct elf_final_link_info * finfo,bfd * input_bfd)8325 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
8326 {
8327 int (*relocate_section)
8328 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
8329 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
8330 bfd *output_bfd;
8331 Elf_Internal_Shdr *symtab_hdr;
8332 size_t locsymcount;
8333 size_t extsymoff;
8334 Elf_Internal_Sym *isymbuf;
8335 Elf_Internal_Sym *isym;
8336 Elf_Internal_Sym *isymend;
8337 long *pindex;
8338 asection **ppsection;
8339 asection *o;
8340 const struct elf_backend_data *bed;
8341 struct elf_link_hash_entry **sym_hashes;
8342
8343 output_bfd = finfo->output_bfd;
8344 bed = get_elf_backend_data (output_bfd);
8345 relocate_section = bed->elf_backend_relocate_section;
8346
8347 /* If this is a dynamic object, we don't want to do anything here:
8348 we don't want the local symbols, and we don't want the section
8349 contents. */
8350 if ((input_bfd->flags & DYNAMIC) != 0)
8351 return TRUE;
8352
8353 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8354 if (elf_bad_symtab (input_bfd))
8355 {
8356 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
8357 extsymoff = 0;
8358 }
8359 else
8360 {
8361 locsymcount = symtab_hdr->sh_info;
8362 extsymoff = symtab_hdr->sh_info;
8363 }
8364
8365 /* Read the local symbols. */
8366 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
8367 if (isymbuf == NULL && locsymcount != 0)
8368 {
8369 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
8370 finfo->internal_syms,
8371 finfo->external_syms,
8372 finfo->locsym_shndx);
8373 if (isymbuf == NULL)
8374 return FALSE;
8375 }
8376 /* evaluate_complex_relocation_symbols looks for symbols in
8377 finfo->internal_syms. */
8378 else if (isymbuf != NULL && locsymcount != 0)
8379 {
8380 bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
8381 finfo->internal_syms,
8382 finfo->external_syms,
8383 finfo->locsym_shndx);
8384 }
8385
8386 /* Find local symbol sections and adjust values of symbols in
8387 SEC_MERGE sections. Write out those local symbols we know are
8388 going into the output file. */
8389 isymend = isymbuf + locsymcount;
8390 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
8391 isym < isymend;
8392 isym++, pindex++, ppsection++)
8393 {
8394 asection *isec;
8395 const char *name;
8396 Elf_Internal_Sym osym;
8397
8398 *pindex = -1;
8399
8400 if (elf_bad_symtab (input_bfd))
8401 {
8402 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
8403 {
8404 *ppsection = NULL;
8405 continue;
8406 }
8407 }
8408
8409 if (isym->st_shndx == SHN_UNDEF)
8410 isec = bfd_und_section_ptr;
8411 else if (isym->st_shndx < SHN_LORESERVE
8412 || isym->st_shndx > SHN_HIRESERVE)
8413 {
8414 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
8415 if (isec
8416 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
8417 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
8418 isym->st_value =
8419 _bfd_merged_section_offset (output_bfd, &isec,
8420 elf_section_data (isec)->sec_info,
8421 isym->st_value);
8422 }
8423 else if (isym->st_shndx == SHN_ABS)
8424 isec = bfd_abs_section_ptr;
8425 else if (isym->st_shndx == SHN_COMMON)
8426 isec = bfd_com_section_ptr;
8427 else
8428 {
8429 /* Don't attempt to output symbols with st_shnx in the
8430 reserved range other than SHN_ABS and SHN_COMMON. */
8431 *ppsection = NULL;
8432 continue;
8433 }
8434
8435 *ppsection = isec;
8436
8437 /* Don't output the first, undefined, symbol. */
8438 if (ppsection == finfo->sections)
8439 continue;
8440
8441 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
8442 {
8443 /* We never output section symbols. Instead, we use the
8444 section symbol of the corresponding section in the output
8445 file. */
8446 continue;
8447 }
8448
8449 /* If we are stripping all symbols, we don't want to output this
8450 one. */
8451 if (finfo->info->strip == strip_all)
8452 continue;
8453
8454 /* If we are discarding all local symbols, we don't want to
8455 output this one. If we are generating a relocatable output
8456 file, then some of the local symbols may be required by
8457 relocs; we output them below as we discover that they are
8458 needed. */
8459 if (finfo->info->discard == discard_all)
8460 continue;
8461
8462 /* If this symbol is defined in a section which we are
8463 discarding, we don't need to keep it. */
8464 if (isym->st_shndx != SHN_UNDEF
8465 && (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
8466 && (isec == NULL
8467 || bfd_section_removed_from_list (output_bfd,
8468 isec->output_section)))
8469 continue;
8470
8471 /* Get the name of the symbol. */
8472 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
8473 isym->st_name);
8474 if (name == NULL)
8475 return FALSE;
8476
8477 /* See if we are discarding symbols with this name. */
8478 if ((finfo->info->strip == strip_some
8479 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
8480 == NULL))
8481 || (((finfo->info->discard == discard_sec_merge
8482 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
8483 || finfo->info->discard == discard_l)
8484 && bfd_is_local_label_name (input_bfd, name)))
8485 continue;
8486
8487 /* If we get here, we are going to output this symbol. */
8488
8489 osym = *isym;
8490
8491 /* Adjust the section index for the output file. */
8492 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
8493 isec->output_section);
8494 if (osym.st_shndx == SHN_BAD)
8495 return FALSE;
8496
8497 *pindex = bfd_get_symcount (output_bfd);
8498
8499 /* ELF symbols in relocatable files are section relative, but
8500 in executable files they are virtual addresses. Note that
8501 this code assumes that all ELF sections have an associated
8502 BFD section with a reasonable value for output_offset; below
8503 we assume that they also have a reasonable value for
8504 output_section. Any special sections must be set up to meet
8505 these requirements. */
8506 osym.st_value += isec->output_offset;
8507 if (! finfo->info->relocatable)
8508 {
8509 osym.st_value += isec->output_section->vma;
8510 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
8511 {
8512 /* STT_TLS symbols are relative to PT_TLS segment base. */
8513 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
8514 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
8515 }
8516 }
8517
8518 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
8519 return FALSE;
8520 }
8521
8522 if (! evaluate_complex_relocation_symbols (input_bfd, finfo, locsymcount))
8523 return FALSE;
8524
8525 /* Relocate the contents of each section. */
8526 sym_hashes = elf_sym_hashes (input_bfd);
8527 for (o = input_bfd->sections; o != NULL; o = o->next)
8528 {
8529 bfd_byte *contents;
8530
8531 if (! o->linker_mark)
8532 {
8533 /* This section was omitted from the link. */
8534 continue;
8535 }
8536
8537 if ((o->flags & SEC_HAS_CONTENTS) == 0
8538 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
8539 continue;
8540
8541 if ((o->flags & SEC_LINKER_CREATED) != 0)
8542 {
8543 /* Section was created by _bfd_elf_link_create_dynamic_sections
8544 or somesuch. */
8545 continue;
8546 }
8547
8548 /* Get the contents of the section. They have been cached by a
8549 relaxation routine. Note that o is a section in an input
8550 file, so the contents field will not have been set by any of
8551 the routines which work on output files. */
8552 if (elf_section_data (o)->this_hdr.contents != NULL)
8553 contents = elf_section_data (o)->this_hdr.contents;
8554 else
8555 {
8556 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
8557
8558 contents = finfo->contents;
8559 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
8560 return FALSE;
8561 }
8562
8563 if ((o->flags & SEC_RELOC) != 0)
8564 {
8565 Elf_Internal_Rela *internal_relocs;
8566 bfd_vma r_type_mask;
8567 int r_sym_shift;
8568 int ret;
8569
8570 /* Get the swapped relocs. */
8571 internal_relocs
8572 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
8573 finfo->internal_relocs, FALSE);
8574 if (internal_relocs == NULL
8575 && o->reloc_count > 0)
8576 return FALSE;
8577
8578 if (bed->s->arch_size == 32)
8579 {
8580 r_type_mask = 0xff;
8581 r_sym_shift = 8;
8582 }
8583 else
8584 {
8585 r_type_mask = 0xffffffff;
8586 r_sym_shift = 32;
8587 }
8588
8589 /* Run through the relocs looking for any against symbols
8590 from discarded sections and section symbols from
8591 removed link-once sections. Complain about relocs
8592 against discarded sections. Zero relocs against removed
8593 link-once sections. */
8594 if (!elf_section_ignore_discarded_relocs (o))
8595 {
8596 Elf_Internal_Rela *rel, *relend;
8597 unsigned int action = (*bed->action_discarded) (o);
8598
8599 rel = internal_relocs;
8600 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
8601 for ( ; rel < relend; rel++)
8602 {
8603 unsigned long r_symndx = rel->r_info >> r_sym_shift;
8604 asection **ps, *sec;
8605 struct elf_link_hash_entry *h = NULL;
8606 const char *sym_name;
8607
8608 if (r_symndx == STN_UNDEF)
8609 continue;
8610
8611 if (r_symndx >= locsymcount
8612 || (elf_bad_symtab (input_bfd)
8613 && finfo->sections[r_symndx] == NULL))
8614 {
8615 h = sym_hashes[r_symndx - extsymoff];
8616
8617 /* Badly formatted input files can contain relocs that
8618 reference non-existant symbols. Check here so that
8619 we do not seg fault. */
8620 if (h == NULL)
8621 {
8622 char buffer [32];
8623
8624 sprintf_vma (buffer, rel->r_info);
8625 (*_bfd_error_handler)
8626 (_("error: %B contains a reloc (0x%s) for section %A "
8627 "that references a non-existent global symbol"),
8628 input_bfd, o, buffer);
8629 bfd_set_error (bfd_error_bad_value);
8630 return FALSE;
8631 }
8632
8633 while (h->root.type == bfd_link_hash_indirect
8634 || h->root.type == bfd_link_hash_warning)
8635 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8636
8637 if (h->root.type != bfd_link_hash_defined
8638 && h->root.type != bfd_link_hash_defweak)
8639 continue;
8640
8641 ps = &h->root.u.def.section;
8642 sym_name = h->root.root.string;
8643 }
8644 else
8645 {
8646 Elf_Internal_Sym *sym = isymbuf + r_symndx;
8647 ps = &finfo->sections[r_symndx];
8648 sym_name = bfd_elf_sym_name (input_bfd,
8649 symtab_hdr,
8650 sym, *ps);
8651 }
8652
8653 /* Complain if the definition comes from a
8654 discarded section. */
8655 if ((sec = *ps) != NULL && elf_discarded_section (sec))
8656 {
8657 BFD_ASSERT (r_symndx != 0);
8658 if (action & COMPLAIN)
8659 (*finfo->info->callbacks->einfo)
8660 (_("%X`%s' referenced in section `%A' of %B: "
8661 "defined in discarded section `%A' of %B\n"),
8662 sym_name, o, input_bfd, sec, sec->owner);
8663
8664 /* Try to do the best we can to support buggy old
8665 versions of gcc. Pretend that the symbol is
8666 really defined in the kept linkonce section.
8667 FIXME: This is quite broken. Modifying the
8668 symbol here means we will be changing all later
8669 uses of the symbol, not just in this section. */
8670 if (action & PRETEND)
8671 {
8672 asection *kept;
8673
8674 kept = _bfd_elf_check_kept_section (sec,
8675 finfo->info);
8676 if (kept != NULL)
8677 {
8678 *ps = kept;
8679 continue;
8680 }
8681 }
8682 }
8683 }
8684 }
8685
8686 /* Relocate the section by invoking a back end routine.
8687
8688 The back end routine is responsible for adjusting the
8689 section contents as necessary, and (if using Rela relocs
8690 and generating a relocatable output file) adjusting the
8691 reloc addend as necessary.
8692
8693 The back end routine does not have to worry about setting
8694 the reloc address or the reloc symbol index.
8695
8696 The back end routine is given a pointer to the swapped in
8697 internal symbols, and can access the hash table entries
8698 for the external symbols via elf_sym_hashes (input_bfd).
8699
8700 When generating relocatable output, the back end routine
8701 must handle STB_LOCAL/STT_SECTION symbols specially. The
8702 output symbol is going to be a section symbol
8703 corresponding to the output section, which will require
8704 the addend to be adjusted. */
8705
8706 ret = (*relocate_section) (output_bfd, finfo->info,
8707 input_bfd, o, contents,
8708 internal_relocs,
8709 isymbuf,
8710 finfo->sections);
8711 if (!ret)
8712 return FALSE;
8713
8714 if (ret == 2
8715 || finfo->info->relocatable
8716 || finfo->info->emitrelocations)
8717 {
8718 Elf_Internal_Rela *irela;
8719 Elf_Internal_Rela *irelaend;
8720 bfd_vma last_offset;
8721 struct elf_link_hash_entry **rel_hash;
8722 struct elf_link_hash_entry **rel_hash_list;
8723 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
8724 unsigned int next_erel;
8725 bfd_boolean rela_normal;
8726
8727 input_rel_hdr = &elf_section_data (o)->rel_hdr;
8728 rela_normal = (bed->rela_normal
8729 && (input_rel_hdr->sh_entsize
8730 == bed->s->sizeof_rela));
8731
8732 /* Adjust the reloc addresses and symbol indices. */
8733
8734 irela = internal_relocs;
8735 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
8736 rel_hash = (elf_section_data (o->output_section)->rel_hashes
8737 + elf_section_data (o->output_section)->rel_count
8738 + elf_section_data (o->output_section)->rel_count2);
8739 rel_hash_list = rel_hash;
8740 last_offset = o->output_offset;
8741 if (!finfo->info->relocatable)
8742 last_offset += o->output_section->vma;
8743 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
8744 {
8745 unsigned long r_symndx;
8746 asection *sec;
8747 Elf_Internal_Sym sym;
8748
8749 if (next_erel == bed->s->int_rels_per_ext_rel)
8750 {
8751 rel_hash++;
8752 next_erel = 0;
8753 }
8754
8755 irela->r_offset = _bfd_elf_section_offset (output_bfd,
8756 finfo->info, o,
8757 irela->r_offset);
8758 if (irela->r_offset >= (bfd_vma) -2)
8759 {
8760 /* This is a reloc for a deleted entry or somesuch.
8761 Turn it into an R_*_NONE reloc, at the same
8762 offset as the last reloc. elf_eh_frame.c and
8763 bfd_elf_discard_info rely on reloc offsets
8764 being ordered. */
8765 irela->r_offset = last_offset;
8766 irela->r_info = 0;
8767 irela->r_addend = 0;
8768 continue;
8769 }
8770
8771 irela->r_offset += o->output_offset;
8772
8773 /* Relocs in an executable have to be virtual addresses. */
8774 if (!finfo->info->relocatable)
8775 irela->r_offset += o->output_section->vma;
8776
8777 last_offset = irela->r_offset;
8778
8779 r_symndx = irela->r_info >> r_sym_shift;
8780 if (r_symndx == STN_UNDEF)
8781 continue;
8782
8783 if (r_symndx >= locsymcount
8784 || (elf_bad_symtab (input_bfd)
8785 && finfo->sections[r_symndx] == NULL))
8786 {
8787 struct elf_link_hash_entry *rh;
8788 unsigned long indx;
8789
8790 /* This is a reloc against a global symbol. We
8791 have not yet output all the local symbols, so
8792 we do not know the symbol index of any global
8793 symbol. We set the rel_hash entry for this
8794 reloc to point to the global hash table entry
8795 for this symbol. The symbol index is then
8796 set at the end of bfd_elf_final_link. */
8797 indx = r_symndx - extsymoff;
8798 rh = elf_sym_hashes (input_bfd)[indx];
8799 while (rh->root.type == bfd_link_hash_indirect
8800 || rh->root.type == bfd_link_hash_warning)
8801 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
8802
8803 /* Setting the index to -2 tells
8804 elf_link_output_extsym that this symbol is
8805 used by a reloc. */
8806 BFD_ASSERT (rh->indx < 0);
8807 rh->indx = -2;
8808
8809 *rel_hash = rh;
8810
8811 continue;
8812 }
8813
8814 /* This is a reloc against a local symbol. */
8815
8816 *rel_hash = NULL;
8817 sym = isymbuf[r_symndx];
8818 sec = finfo->sections[r_symndx];
8819 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
8820 {
8821 /* I suppose the backend ought to fill in the
8822 section of any STT_SECTION symbol against a
8823 processor specific section. */
8824 r_symndx = 0;
8825 if (bfd_is_abs_section (sec))
8826 ;
8827 else if (sec == NULL || sec->owner == NULL)
8828 {
8829 bfd_set_error (bfd_error_bad_value);
8830 return FALSE;
8831 }
8832 else
8833 {
8834 asection *osec = sec->output_section;
8835
8836 /* If we have discarded a section, the output
8837 section will be the absolute section. In
8838 case of discarded SEC_MERGE sections, use
8839 the kept section. relocate_section should
8840 have already handled discarded linkonce
8841 sections. */
8842 if (bfd_is_abs_section (osec)
8843 && sec->kept_section != NULL
8844 && sec->kept_section->output_section != NULL)
8845 {
8846 osec = sec->kept_section->output_section;
8847 irela->r_addend -= osec->vma;
8848 }
8849
8850 if (!bfd_is_abs_section (osec))
8851 {
8852 r_symndx = osec->target_index;
8853 if (r_symndx == 0)
8854 {
8855 struct elf_link_hash_table *htab;
8856 asection *oi;
8857
8858 htab = elf_hash_table (finfo->info);
8859 oi = htab->text_index_section;
8860 if ((osec->flags & SEC_READONLY) == 0
8861 && htab->data_index_section != NULL)
8862 oi = htab->data_index_section;
8863
8864 if (oi != NULL)
8865 {
8866 irela->r_addend += osec->vma - oi->vma;
8867 r_symndx = oi->target_index;
8868 }
8869 }
8870
8871 BFD_ASSERT (r_symndx != 0);
8872 }
8873 }
8874
8875 /* Adjust the addend according to where the
8876 section winds up in the output section. */
8877 if (rela_normal)
8878 irela->r_addend += sec->output_offset;
8879 }
8880 else
8881 {
8882 if (finfo->indices[r_symndx] == -1)
8883 {
8884 unsigned long shlink;
8885 const char *name;
8886 asection *osec;
8887
8888 if (finfo->info->strip == strip_all)
8889 {
8890 /* You can't do ld -r -s. */
8891 bfd_set_error (bfd_error_invalid_operation);
8892 return FALSE;
8893 }
8894
8895 /* This symbol was skipped earlier, but
8896 since it is needed by a reloc, we
8897 must output it now. */
8898 shlink = symtab_hdr->sh_link;
8899 name = (bfd_elf_string_from_elf_section
8900 (input_bfd, shlink, sym.st_name));
8901 if (name == NULL)
8902 return FALSE;
8903
8904 osec = sec->output_section;
8905 sym.st_shndx =
8906 _bfd_elf_section_from_bfd_section (output_bfd,
8907 osec);
8908 if (sym.st_shndx == SHN_BAD)
8909 return FALSE;
8910
8911 sym.st_value += sec->output_offset;
8912 if (! finfo->info->relocatable)
8913 {
8914 sym.st_value += osec->vma;
8915 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
8916 {
8917 /* STT_TLS symbols are relative to PT_TLS
8918 segment base. */
8919 BFD_ASSERT (elf_hash_table (finfo->info)
8920 ->tls_sec != NULL);
8921 sym.st_value -= (elf_hash_table (finfo->info)
8922 ->tls_sec->vma);
8923 }
8924 }
8925
8926 finfo->indices[r_symndx]
8927 = bfd_get_symcount (output_bfd);
8928
8929 if (! elf_link_output_sym (finfo, name, &sym, sec,
8930 NULL))
8931 return FALSE;
8932 }
8933
8934 r_symndx = finfo->indices[r_symndx];
8935 }
8936
8937 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
8938 | (irela->r_info & r_type_mask));
8939 }
8940
8941 /* Swap out the relocs. */
8942 if (input_rel_hdr->sh_size != 0
8943 && !bed->elf_backend_emit_relocs (output_bfd, o,
8944 input_rel_hdr,
8945 internal_relocs,
8946 rel_hash_list))
8947 return FALSE;
8948
8949 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
8950 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
8951 {
8952 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
8953 * bed->s->int_rels_per_ext_rel);
8954 rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
8955 if (!bed->elf_backend_emit_relocs (output_bfd, o,
8956 input_rel_hdr2,
8957 internal_relocs,
8958 rel_hash_list))
8959 return FALSE;
8960 }
8961 }
8962 }
8963
8964 /* Write out the modified section contents. */
8965 if (bed->elf_backend_write_section
8966 && (*bed->elf_backend_write_section) (output_bfd, finfo->info, o,
8967 contents))
8968 {
8969 /* Section written out. */
8970 }
8971 else switch (o->sec_info_type)
8972 {
8973 case ELF_INFO_TYPE_STABS:
8974 if (! (_bfd_write_section_stabs
8975 (output_bfd,
8976 &elf_hash_table (finfo->info)->stab_info,
8977 o, &elf_section_data (o)->sec_info, contents)))
8978 return FALSE;
8979 break;
8980 case ELF_INFO_TYPE_MERGE:
8981 if (! _bfd_write_merged_section (output_bfd, o,
8982 elf_section_data (o)->sec_info))
8983 return FALSE;
8984 break;
8985 case ELF_INFO_TYPE_EH_FRAME:
8986 {
8987 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
8988 o, contents))
8989 return FALSE;
8990 }
8991 break;
8992 default:
8993 {
8994 if (! (o->flags & SEC_EXCLUDE)
8995 && ! bfd_set_section_contents (output_bfd, o->output_section,
8996 contents,
8997 (file_ptr) o->output_offset,
8998 o->size))
8999 return FALSE;
9000 }
9001 break;
9002 }
9003 }
9004
9005 return TRUE;
9006 }
9007
9008 /* Generate a reloc when linking an ELF file. This is a reloc
9009 requested by the linker, and does not come from any input file. This
9010 is used to build constructor and destructor tables when linking
9011 with -Ur. */
9012
9013 static bfd_boolean
elf_reloc_link_order(bfd * output_bfd,struct bfd_link_info * info,asection * output_section,struct bfd_link_order * link_order)9014 elf_reloc_link_order (bfd *output_bfd,
9015 struct bfd_link_info *info,
9016 asection *output_section,
9017 struct bfd_link_order *link_order)
9018 {
9019 reloc_howto_type *howto;
9020 long indx;
9021 bfd_vma offset;
9022 bfd_vma addend;
9023 struct elf_link_hash_entry **rel_hash_ptr;
9024 Elf_Internal_Shdr *rel_hdr;
9025 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
9026 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
9027 bfd_byte *erel;
9028 unsigned int i;
9029
9030 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
9031 if (howto == NULL)
9032 {
9033 bfd_set_error (bfd_error_bad_value);
9034 return FALSE;
9035 }
9036
9037 addend = link_order->u.reloc.p->addend;
9038
9039 /* Figure out the symbol index. */
9040 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
9041 + elf_section_data (output_section)->rel_count
9042 + elf_section_data (output_section)->rel_count2);
9043 if (link_order->type == bfd_section_reloc_link_order)
9044 {
9045 indx = link_order->u.reloc.p->u.section->target_index;
9046 BFD_ASSERT (indx != 0);
9047 *rel_hash_ptr = NULL;
9048 }
9049 else
9050 {
9051 struct elf_link_hash_entry *h;
9052
9053 /* Treat a reloc against a defined symbol as though it were
9054 actually against the section. */
9055 h = ((struct elf_link_hash_entry *)
9056 bfd_wrapped_link_hash_lookup (output_bfd, info,
9057 link_order->u.reloc.p->u.name,
9058 FALSE, FALSE, TRUE));
9059 if (h != NULL
9060 && (h->root.type == bfd_link_hash_defined
9061 || h->root.type == bfd_link_hash_defweak))
9062 {
9063 asection *section;
9064
9065 section = h->root.u.def.section;
9066 indx = section->output_section->target_index;
9067 *rel_hash_ptr = NULL;
9068 /* It seems that we ought to add the symbol value to the
9069 addend here, but in practice it has already been added
9070 because it was passed to constructor_callback. */
9071 addend += section->output_section->vma + section->output_offset;
9072 }
9073 else if (h != NULL)
9074 {
9075 /* Setting the index to -2 tells elf_link_output_extsym that
9076 this symbol is used by a reloc. */
9077 h->indx = -2;
9078 *rel_hash_ptr = h;
9079 indx = 0;
9080 }
9081 else
9082 {
9083 if (! ((*info->callbacks->unattached_reloc)
9084 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
9085 return FALSE;
9086 indx = 0;
9087 }
9088 }
9089
9090 /* If this is an inplace reloc, we must write the addend into the
9091 object file. */
9092 if (howto->partial_inplace && addend != 0)
9093 {
9094 bfd_size_type size;
9095 bfd_reloc_status_type rstat;
9096 bfd_byte *buf;
9097 bfd_boolean ok;
9098 const char *sym_name;
9099
9100 size = bfd_get_reloc_size (howto);
9101 buf = bfd_zmalloc (size);
9102 if (buf == NULL)
9103 return FALSE;
9104 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
9105 switch (rstat)
9106 {
9107 case bfd_reloc_ok:
9108 break;
9109
9110 default:
9111 case bfd_reloc_outofrange:
9112 abort ();
9113
9114 case bfd_reloc_overflow:
9115 if (link_order->type == bfd_section_reloc_link_order)
9116 sym_name = bfd_section_name (output_bfd,
9117 link_order->u.reloc.p->u.section);
9118 else
9119 sym_name = link_order->u.reloc.p->u.name;
9120 if (! ((*info->callbacks->reloc_overflow)
9121 (info, NULL, sym_name, howto->name, addend, NULL,
9122 NULL, (bfd_vma) 0)))
9123 {
9124 free (buf);
9125 return FALSE;
9126 }
9127 break;
9128 }
9129 ok = bfd_set_section_contents (output_bfd, output_section, buf,
9130 link_order->offset, size);
9131 free (buf);
9132 if (! ok)
9133 return FALSE;
9134 }
9135
9136 /* The address of a reloc is relative to the section in a
9137 relocatable file, and is a virtual address in an executable
9138 file. */
9139 offset = link_order->offset;
9140 if (! info->relocatable)
9141 offset += output_section->vma;
9142
9143 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
9144 {
9145 irel[i].r_offset = offset;
9146 irel[i].r_info = 0;
9147 irel[i].r_addend = 0;
9148 }
9149 if (bed->s->arch_size == 32)
9150 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
9151 else
9152 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
9153
9154 rel_hdr = &elf_section_data (output_section)->rel_hdr;
9155 erel = rel_hdr->contents;
9156 if (rel_hdr->sh_type == SHT_REL)
9157 {
9158 erel += (elf_section_data (output_section)->rel_count
9159 * bed->s->sizeof_rel);
9160 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
9161 }
9162 else
9163 {
9164 irel[0].r_addend = addend;
9165 erel += (elf_section_data (output_section)->rel_count
9166 * bed->s->sizeof_rela);
9167 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
9168 }
9169
9170 ++elf_section_data (output_section)->rel_count;
9171
9172 return TRUE;
9173 }
9174
9175
9176 /* Get the output vma of the section pointed to by the sh_link field. */
9177
9178 static bfd_vma
elf_get_linked_section_vma(struct bfd_link_order * p)9179 elf_get_linked_section_vma (struct bfd_link_order *p)
9180 {
9181 Elf_Internal_Shdr **elf_shdrp;
9182 asection *s;
9183 int elfsec;
9184
9185 s = p->u.indirect.section;
9186 elf_shdrp = elf_elfsections (s->owner);
9187 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
9188 elfsec = elf_shdrp[elfsec]->sh_link;
9189 /* PR 290:
9190 The Intel C compiler generates SHT_IA_64_UNWIND with
9191 SHF_LINK_ORDER. But it doesn't set the sh_link or
9192 sh_info fields. Hence we could get the situation
9193 where elfsec is 0. */
9194 if (elfsec == 0)
9195 {
9196 const struct elf_backend_data *bed
9197 = get_elf_backend_data (s->owner);
9198 if (bed->link_order_error_handler)
9199 bed->link_order_error_handler
9200 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
9201 return 0;
9202 }
9203 else
9204 {
9205 s = elf_shdrp[elfsec]->bfd_section;
9206 return s->output_section->vma + s->output_offset;
9207 }
9208 }
9209
9210
9211 /* Compare two sections based on the locations of the sections they are
9212 linked to. Used by elf_fixup_link_order. */
9213
9214 static int
compare_link_order(const void * a,const void * b)9215 compare_link_order (const void * a, const void * b)
9216 {
9217 bfd_vma apos;
9218 bfd_vma bpos;
9219
9220 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
9221 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
9222 if (apos < bpos)
9223 return -1;
9224 return apos > bpos;
9225 }
9226
9227
9228 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
9229 order as their linked sections. Returns false if this could not be done
9230 because an output section includes both ordered and unordered
9231 sections. Ideally we'd do this in the linker proper. */
9232
9233 static bfd_boolean
elf_fixup_link_order(bfd * abfd,asection * o)9234 elf_fixup_link_order (bfd *abfd, asection *o)
9235 {
9236 int seen_linkorder;
9237 int seen_other;
9238 int n;
9239 struct bfd_link_order *p;
9240 bfd *sub;
9241 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9242 unsigned elfsec;
9243 struct bfd_link_order **sections;
9244 asection *s, *other_sec, *linkorder_sec;
9245 bfd_vma offset;
9246
9247 other_sec = NULL;
9248 linkorder_sec = NULL;
9249 seen_other = 0;
9250 seen_linkorder = 0;
9251 for (p = o->map_head.link_order; p != NULL; p = p->next)
9252 {
9253 if (p->type == bfd_indirect_link_order)
9254 {
9255 s = p->u.indirect.section;
9256 sub = s->owner;
9257 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
9258 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass
9259 && (elfsec = _bfd_elf_section_from_bfd_section (sub, s))
9260 && elfsec < elf_numsections (sub)
9261 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
9262 {
9263 seen_linkorder++;
9264 linkorder_sec = s;
9265 }
9266 else
9267 {
9268 seen_other++;
9269 other_sec = s;
9270 }
9271 }
9272 else
9273 seen_other++;
9274
9275 if (seen_other && seen_linkorder)
9276 {
9277 if (other_sec && linkorder_sec)
9278 (*_bfd_error_handler) (_("%A has both ordered [`%A' in %B] and unordered [`%A' in %B] sections"),
9279 o, linkorder_sec,
9280 linkorder_sec->owner, other_sec,
9281 other_sec->owner);
9282 else
9283 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
9284 o);
9285 bfd_set_error (bfd_error_bad_value);
9286 return FALSE;
9287 }
9288 }
9289
9290 if (!seen_linkorder)
9291 return TRUE;
9292
9293 sections = (struct bfd_link_order **)
9294 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
9295 seen_linkorder = 0;
9296
9297 for (p = o->map_head.link_order; p != NULL; p = p->next)
9298 {
9299 sections[seen_linkorder++] = p;
9300 }
9301 /* Sort the input sections in the order of their linked section. */
9302 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
9303 compare_link_order);
9304
9305 /* Change the offsets of the sections. */
9306 offset = 0;
9307 for (n = 0; n < seen_linkorder; n++)
9308 {
9309 s = sections[n]->u.indirect.section;
9310 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
9311 s->output_offset = offset;
9312 sections[n]->offset = offset;
9313 offset += sections[n]->size;
9314 }
9315
9316 return TRUE;
9317 }
9318
9319
9320 /* Do the final step of an ELF link. */
9321
9322 bfd_boolean
bfd_elf_final_link(bfd * abfd,struct bfd_link_info * info)9323 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
9324 {
9325 bfd_boolean dynamic;
9326 bfd_boolean emit_relocs;
9327 bfd *dynobj;
9328 struct elf_final_link_info finfo;
9329 register asection *o;
9330 register struct bfd_link_order *p;
9331 register bfd *sub;
9332 bfd_size_type max_contents_size;
9333 bfd_size_type max_external_reloc_size;
9334 bfd_size_type max_internal_reloc_count;
9335 bfd_size_type max_sym_count;
9336 bfd_size_type max_sym_shndx_count;
9337 file_ptr off;
9338 Elf_Internal_Sym elfsym;
9339 unsigned int i;
9340 Elf_Internal_Shdr *symtab_hdr;
9341 Elf_Internal_Shdr *symtab_shndx_hdr;
9342 Elf_Internal_Shdr *symstrtab_hdr;
9343 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9344 struct elf_outext_info eoinfo;
9345 bfd_boolean merged;
9346 size_t relativecount = 0;
9347 asection *reldyn = 0;
9348 bfd_size_type amt;
9349 asection *attr_section = NULL;
9350 bfd_vma attr_size = 0;
9351 const char *std_attrs_section;
9352
9353 if (! is_elf_hash_table (info->hash))
9354 return FALSE;
9355
9356 if (info->shared)
9357 abfd->flags |= DYNAMIC;
9358
9359 dynamic = elf_hash_table (info)->dynamic_sections_created;
9360 dynobj = elf_hash_table (info)->dynobj;
9361
9362 emit_relocs = (info->relocatable
9363 || info->emitrelocations);
9364
9365 finfo.info = info;
9366 finfo.output_bfd = abfd;
9367 finfo.symstrtab = _bfd_elf_stringtab_init ();
9368 if (finfo.symstrtab == NULL)
9369 return FALSE;
9370
9371 if (! dynamic)
9372 {
9373 finfo.dynsym_sec = NULL;
9374 finfo.hash_sec = NULL;
9375 finfo.symver_sec = NULL;
9376 }
9377 else
9378 {
9379 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
9380 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
9381 BFD_ASSERT (finfo.dynsym_sec != NULL);
9382 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
9383 /* Note that it is OK if symver_sec is NULL. */
9384 }
9385
9386 finfo.contents = NULL;
9387 finfo.external_relocs = NULL;
9388 finfo.internal_relocs = NULL;
9389 finfo.external_syms = NULL;
9390 finfo.locsym_shndx = NULL;
9391 finfo.internal_syms = NULL;
9392 finfo.indices = NULL;
9393 finfo.sections = NULL;
9394 finfo.symbuf = NULL;
9395 finfo.symshndxbuf = NULL;
9396 finfo.symbuf_count = 0;
9397 finfo.shndxbuf_size = 0;
9398
9399 /* The object attributes have been merged. Remove the input
9400 sections from the link, and set the contents of the output
9401 secton. */
9402 std_attrs_section = get_elf_backend_data (abfd)->obj_attrs_section;
9403 for (o = abfd->sections; o != NULL; o = o->next)
9404 {
9405 if ((std_attrs_section && strcmp (o->name, std_attrs_section) == 0)
9406 || strcmp (o->name, ".gnu.attributes") == 0)
9407 {
9408 for (p = o->map_head.link_order; p != NULL; p = p->next)
9409 {
9410 asection *input_section;
9411
9412 if (p->type != bfd_indirect_link_order)
9413 continue;
9414 input_section = p->u.indirect.section;
9415 /* Hack: reset the SEC_HAS_CONTENTS flag so that
9416 elf_link_input_bfd ignores this section. */
9417 input_section->flags &= ~SEC_HAS_CONTENTS;
9418 }
9419
9420 attr_size = bfd_elf_obj_attr_size (abfd);
9421 if (attr_size)
9422 {
9423 bfd_set_section_size (abfd, o, attr_size);
9424 attr_section = o;
9425 /* Skip this section later on. */
9426 o->map_head.link_order = NULL;
9427 }
9428 else
9429 o->flags |= SEC_EXCLUDE;
9430 }
9431 }
9432
9433 /* Count up the number of relocations we will output for each output
9434 section, so that we know the sizes of the reloc sections. We
9435 also figure out some maximum sizes. */
9436 max_contents_size = 0;
9437 max_external_reloc_size = 0;
9438 max_internal_reloc_count = 0;
9439 max_sym_count = 0;
9440 max_sym_shndx_count = 0;
9441 merged = FALSE;
9442 for (o = abfd->sections; o != NULL; o = o->next)
9443 {
9444 struct bfd_elf_section_data *esdo = elf_section_data (o);
9445 o->reloc_count = 0;
9446
9447 for (p = o->map_head.link_order; p != NULL; p = p->next)
9448 {
9449 unsigned int reloc_count = 0;
9450 struct bfd_elf_section_data *esdi = NULL;
9451 unsigned int *rel_count1;
9452
9453 if (p->type == bfd_section_reloc_link_order
9454 || p->type == bfd_symbol_reloc_link_order)
9455 reloc_count = 1;
9456 else if (p->type == bfd_indirect_link_order)
9457 {
9458 asection *sec;
9459
9460 sec = p->u.indirect.section;
9461 esdi = elf_section_data (sec);
9462
9463 /* Mark all sections which are to be included in the
9464 link. This will normally be every section. We need
9465 to do this so that we can identify any sections which
9466 the linker has decided to not include. */
9467 sec->linker_mark = TRUE;
9468
9469 if (sec->flags & SEC_MERGE)
9470 merged = TRUE;
9471
9472 if (info->relocatable || info->emitrelocations)
9473 reloc_count = sec->reloc_count;
9474 else if (bed->elf_backend_count_relocs)
9475 {
9476 Elf_Internal_Rela * relocs;
9477
9478 relocs = _bfd_elf_link_read_relocs (sec->owner, sec,
9479 NULL, NULL,
9480 info->keep_memory);
9481
9482 if (relocs != NULL)
9483 {
9484 reloc_count
9485 = (*bed->elf_backend_count_relocs) (sec, relocs);
9486
9487 if (elf_section_data (sec)->relocs != relocs)
9488 free (relocs);
9489 }
9490 }
9491
9492 if (sec->rawsize > max_contents_size)
9493 max_contents_size = sec->rawsize;
9494 if (sec->size > max_contents_size)
9495 max_contents_size = sec->size;
9496
9497 /* We are interested in just local symbols, not all
9498 symbols. */
9499 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
9500 && (sec->owner->flags & DYNAMIC) == 0)
9501 {
9502 size_t sym_count;
9503
9504 if (elf_bad_symtab (sec->owner))
9505 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
9506 / bed->s->sizeof_sym);
9507 else
9508 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
9509
9510 if (sym_count > max_sym_count)
9511 max_sym_count = sym_count;
9512
9513 if (sym_count > max_sym_shndx_count
9514 && elf_symtab_shndx (sec->owner) != 0)
9515 max_sym_shndx_count = sym_count;
9516
9517 if ((sec->flags & SEC_RELOC) != 0)
9518 {
9519 size_t ext_size;
9520
9521 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
9522 if (ext_size > max_external_reloc_size)
9523 max_external_reloc_size = ext_size;
9524 if (sec->reloc_count > max_internal_reloc_count)
9525 max_internal_reloc_count = sec->reloc_count;
9526 }
9527 }
9528 }
9529
9530 if (reloc_count == 0)
9531 continue;
9532
9533 o->reloc_count += reloc_count;
9534
9535 /* MIPS may have a mix of REL and RELA relocs on sections.
9536 To support this curious ABI we keep reloc counts in
9537 elf_section_data too. We must be careful to add the
9538 relocations from the input section to the right output
9539 count. FIXME: Get rid of one count. We have
9540 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
9541 rel_count1 = &esdo->rel_count;
9542 if (esdi != NULL)
9543 {
9544 bfd_boolean same_size;
9545 bfd_size_type entsize1;
9546
9547 entsize1 = esdi->rel_hdr.sh_entsize;
9548 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
9549 || entsize1 == bed->s->sizeof_rela);
9550 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
9551
9552 if (!same_size)
9553 rel_count1 = &esdo->rel_count2;
9554
9555 if (esdi->rel_hdr2 != NULL)
9556 {
9557 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
9558 unsigned int alt_count;
9559 unsigned int *rel_count2;
9560
9561 BFD_ASSERT (entsize2 != entsize1
9562 && (entsize2 == bed->s->sizeof_rel
9563 || entsize2 == bed->s->sizeof_rela));
9564
9565 rel_count2 = &esdo->rel_count2;
9566 if (!same_size)
9567 rel_count2 = &esdo->rel_count;
9568
9569 /* The following is probably too simplistic if the
9570 backend counts output relocs unusually. */
9571 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
9572 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
9573 *rel_count2 += alt_count;
9574 reloc_count -= alt_count;
9575 }
9576 }
9577 *rel_count1 += reloc_count;
9578 }
9579
9580 if (o->reloc_count > 0)
9581 o->flags |= SEC_RELOC;
9582 else
9583 {
9584 /* Explicitly clear the SEC_RELOC flag. The linker tends to
9585 set it (this is probably a bug) and if it is set
9586 assign_section_numbers will create a reloc section. */
9587 o->flags &=~ SEC_RELOC;
9588 }
9589
9590 /* If the SEC_ALLOC flag is not set, force the section VMA to
9591 zero. This is done in elf_fake_sections as well, but forcing
9592 the VMA to 0 here will ensure that relocs against these
9593 sections are handled correctly. */
9594 if ((o->flags & SEC_ALLOC) == 0
9595 && ! o->user_set_vma)
9596 o->vma = 0;
9597 }
9598
9599 if (! info->relocatable && merged)
9600 elf_link_hash_traverse (elf_hash_table (info),
9601 _bfd_elf_link_sec_merge_syms, abfd);
9602
9603 /* Figure out the file positions for everything but the symbol table
9604 and the relocs. We set symcount to force assign_section_numbers
9605 to create a symbol table. */
9606 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
9607 BFD_ASSERT (! abfd->output_has_begun);
9608 if (! _bfd_elf_compute_section_file_positions (abfd, info))
9609 goto error_return;
9610
9611 /* Set sizes, and assign file positions for reloc sections. */
9612 for (o = abfd->sections; o != NULL; o = o->next)
9613 {
9614 if ((o->flags & SEC_RELOC) != 0)
9615 {
9616 if (!(_bfd_elf_link_size_reloc_section
9617 (abfd, &elf_section_data (o)->rel_hdr, o)))
9618 goto error_return;
9619
9620 if (elf_section_data (o)->rel_hdr2
9621 && !(_bfd_elf_link_size_reloc_section
9622 (abfd, elf_section_data (o)->rel_hdr2, o)))
9623 goto error_return;
9624 }
9625
9626 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
9627 to count upwards while actually outputting the relocations. */
9628 elf_section_data (o)->rel_count = 0;
9629 elf_section_data (o)->rel_count2 = 0;
9630 }
9631
9632 _bfd_elf_assign_file_positions_for_relocs (abfd);
9633
9634 /* We have now assigned file positions for all the sections except
9635 .symtab and .strtab. We start the .symtab section at the current
9636 file position, and write directly to it. We build the .strtab
9637 section in memory. */
9638 bfd_get_symcount (abfd) = 0;
9639 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9640 /* sh_name is set in prep_headers. */
9641 symtab_hdr->sh_type = SHT_SYMTAB;
9642 /* sh_flags, sh_addr and sh_size all start off zero. */
9643 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
9644 /* sh_link is set in assign_section_numbers. */
9645 /* sh_info is set below. */
9646 /* sh_offset is set just below. */
9647 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
9648
9649 off = elf_tdata (abfd)->next_file_pos;
9650 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
9651
9652 /* Note that at this point elf_tdata (abfd)->next_file_pos is
9653 incorrect. We do not yet know the size of the .symtab section.
9654 We correct next_file_pos below, after we do know the size. */
9655
9656 /* Allocate a buffer to hold swapped out symbols. This is to avoid
9657 continuously seeking to the right position in the file. */
9658 if (! info->keep_memory || max_sym_count < 20)
9659 finfo.symbuf_size = 20;
9660 else
9661 finfo.symbuf_size = max_sym_count;
9662 amt = finfo.symbuf_size;
9663 amt *= bed->s->sizeof_sym;
9664 finfo.symbuf = bfd_malloc (amt);
9665 if (finfo.symbuf == NULL)
9666 goto error_return;
9667 if (elf_numsections (abfd) > SHN_LORESERVE)
9668 {
9669 /* Wild guess at number of output symbols. realloc'd as needed. */
9670 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
9671 finfo.shndxbuf_size = amt;
9672 amt *= sizeof (Elf_External_Sym_Shndx);
9673 finfo.symshndxbuf = bfd_zmalloc (amt);
9674 if (finfo.symshndxbuf == NULL)
9675 goto error_return;
9676 }
9677
9678 /* Start writing out the symbol table. The first symbol is always a
9679 dummy symbol. */
9680 if (info->strip != strip_all
9681 || emit_relocs)
9682 {
9683 elfsym.st_value = 0;
9684 elfsym.st_size = 0;
9685 elfsym.st_info = 0;
9686 elfsym.st_other = 0;
9687 elfsym.st_shndx = SHN_UNDEF;
9688 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
9689 NULL))
9690 goto error_return;
9691 }
9692
9693 /* Output a symbol for each section. We output these even if we are
9694 discarding local symbols, since they are used for relocs. These
9695 symbols have no names. We store the index of each one in the
9696 index field of the section, so that we can find it again when
9697 outputting relocs. */
9698 if (info->strip != strip_all
9699 || emit_relocs)
9700 {
9701 elfsym.st_size = 0;
9702 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
9703 elfsym.st_other = 0;
9704 elfsym.st_value = 0;
9705 for (i = 1; i < elf_numsections (abfd); i++)
9706 {
9707 o = bfd_section_from_elf_index (abfd, i);
9708 if (o != NULL)
9709 {
9710 o->target_index = bfd_get_symcount (abfd);
9711 elfsym.st_shndx = i;
9712 if (!info->relocatable)
9713 elfsym.st_value = o->vma;
9714 if (!elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
9715 goto error_return;
9716 }
9717 if (i == SHN_LORESERVE - 1)
9718 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
9719 }
9720 }
9721
9722 /* Allocate some memory to hold information read in from the input
9723 files. */
9724 if (max_contents_size != 0)
9725 {
9726 finfo.contents = bfd_malloc (max_contents_size);
9727 if (finfo.contents == NULL)
9728 goto error_return;
9729 }
9730
9731 if (max_external_reloc_size != 0)
9732 {
9733 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
9734 if (finfo.external_relocs == NULL)
9735 goto error_return;
9736 }
9737
9738 if (max_internal_reloc_count != 0)
9739 {
9740 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
9741 amt *= sizeof (Elf_Internal_Rela);
9742 finfo.internal_relocs = bfd_malloc (amt);
9743 if (finfo.internal_relocs == NULL)
9744 goto error_return;
9745 }
9746
9747 if (max_sym_count != 0)
9748 {
9749 amt = max_sym_count * bed->s->sizeof_sym;
9750 finfo.external_syms = bfd_malloc (amt);
9751 if (finfo.external_syms == NULL)
9752 goto error_return;
9753
9754 amt = max_sym_count * sizeof (Elf_Internal_Sym);
9755 finfo.internal_syms = bfd_malloc (amt);
9756 if (finfo.internal_syms == NULL)
9757 goto error_return;
9758
9759 amt = max_sym_count * sizeof (long);
9760 finfo.indices = bfd_malloc (amt);
9761 if (finfo.indices == NULL)
9762 goto error_return;
9763
9764 amt = max_sym_count * sizeof (asection *);
9765 finfo.sections = bfd_malloc (amt);
9766 if (finfo.sections == NULL)
9767 goto error_return;
9768 }
9769
9770 if (max_sym_shndx_count != 0)
9771 {
9772 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
9773 finfo.locsym_shndx = bfd_malloc (amt);
9774 if (finfo.locsym_shndx == NULL)
9775 goto error_return;
9776 }
9777
9778 if (elf_hash_table (info)->tls_sec)
9779 {
9780 bfd_vma base, end = 0;
9781 asection *sec;
9782
9783 for (sec = elf_hash_table (info)->tls_sec;
9784 sec && (sec->flags & SEC_THREAD_LOCAL);
9785 sec = sec->next)
9786 {
9787 bfd_size_type size = sec->size;
9788
9789 if (size == 0
9790 && (sec->flags & SEC_HAS_CONTENTS) == 0)
9791 {
9792 struct bfd_link_order *o = sec->map_tail.link_order;
9793 if (o != NULL)
9794 size = o->offset + o->size;
9795 }
9796 end = sec->vma + size;
9797 }
9798 base = elf_hash_table (info)->tls_sec->vma;
9799 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
9800 elf_hash_table (info)->tls_size = end - base;
9801 }
9802
9803 /* Reorder SHF_LINK_ORDER sections. */
9804 for (o = abfd->sections; o != NULL; o = o->next)
9805 {
9806 if (!elf_fixup_link_order (abfd, o))
9807 return FALSE;
9808 }
9809
9810 /* Since ELF permits relocations to be against local symbols, we
9811 must have the local symbols available when we do the relocations.
9812 Since we would rather only read the local symbols once, and we
9813 would rather not keep them in memory, we handle all the
9814 relocations for a single input file at the same time.
9815
9816 Unfortunately, there is no way to know the total number of local
9817 symbols until we have seen all of them, and the local symbol
9818 indices precede the global symbol indices. This means that when
9819 we are generating relocatable output, and we see a reloc against
9820 a global symbol, we can not know the symbol index until we have
9821 finished examining all the local symbols to see which ones we are
9822 going to output. To deal with this, we keep the relocations in
9823 memory, and don't output them until the end of the link. This is
9824 an unfortunate waste of memory, but I don't see a good way around
9825 it. Fortunately, it only happens when performing a relocatable
9826 link, which is not the common case. FIXME: If keep_memory is set
9827 we could write the relocs out and then read them again; I don't
9828 know how bad the memory loss will be. */
9829
9830 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9831 sub->output_has_begun = FALSE;
9832 for (o = abfd->sections; o != NULL; o = o->next)
9833 {
9834 for (p = o->map_head.link_order; p != NULL; p = p->next)
9835 {
9836 if (p->type == bfd_indirect_link_order
9837 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
9838 == bfd_target_elf_flavour)
9839 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
9840 {
9841 if (! sub->output_has_begun)
9842 {
9843 if (! elf_link_input_bfd (&finfo, sub))
9844 goto error_return;
9845 sub->output_has_begun = TRUE;
9846 }
9847 }
9848 else if (p->type == bfd_section_reloc_link_order
9849 || p->type == bfd_symbol_reloc_link_order)
9850 {
9851 if (! elf_reloc_link_order (abfd, info, o, p))
9852 goto error_return;
9853 }
9854 else
9855 {
9856 if (! _bfd_default_link_order (abfd, info, o, p))
9857 goto error_return;
9858 }
9859 }
9860 }
9861
9862 /* Free symbol buffer if needed. */
9863 if (!info->reduce_memory_overheads)
9864 {
9865 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9866 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
9867 && elf_tdata (sub)->symbuf)
9868 {
9869 free (elf_tdata (sub)->symbuf);
9870 elf_tdata (sub)->symbuf = NULL;
9871 }
9872 }
9873
9874 /* Output any global symbols that got converted to local in a
9875 version script or due to symbol visibility. We do this in a
9876 separate step since ELF requires all local symbols to appear
9877 prior to any global symbols. FIXME: We should only do this if
9878 some global symbols were, in fact, converted to become local.
9879 FIXME: Will this work correctly with the Irix 5 linker? */
9880 eoinfo.failed = FALSE;
9881 eoinfo.finfo = &finfo;
9882 eoinfo.localsyms = TRUE;
9883 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
9884 &eoinfo);
9885 if (eoinfo.failed)
9886 return FALSE;
9887
9888 /* If backend needs to output some local symbols not present in the hash
9889 table, do it now. */
9890 if (bed->elf_backend_output_arch_local_syms)
9891 {
9892 typedef bfd_boolean (*out_sym_func)
9893 (void *, const char *, Elf_Internal_Sym *, asection *,
9894 struct elf_link_hash_entry *);
9895
9896 if (! ((*bed->elf_backend_output_arch_local_syms)
9897 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
9898 return FALSE;
9899 }
9900
9901 /* That wrote out all the local symbols. Finish up the symbol table
9902 with the global symbols. Even if we want to strip everything we
9903 can, we still need to deal with those global symbols that got
9904 converted to local in a version script. */
9905
9906 /* The sh_info field records the index of the first non local symbol. */
9907 symtab_hdr->sh_info = bfd_get_symcount (abfd);
9908
9909 if (dynamic
9910 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
9911 {
9912 Elf_Internal_Sym sym;
9913 bfd_byte *dynsym = finfo.dynsym_sec->contents;
9914 long last_local = 0;
9915
9916 /* Write out the section symbols for the output sections. */
9917 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
9918 {
9919 asection *s;
9920
9921 sym.st_size = 0;
9922 sym.st_name = 0;
9923 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
9924 sym.st_other = 0;
9925
9926 for (s = abfd->sections; s != NULL; s = s->next)
9927 {
9928 int indx;
9929 bfd_byte *dest;
9930 long dynindx;
9931
9932 dynindx = elf_section_data (s)->dynindx;
9933 if (dynindx <= 0)
9934 continue;
9935 indx = elf_section_data (s)->this_idx;
9936 BFD_ASSERT (indx > 0);
9937 sym.st_shndx = indx;
9938 if (! check_dynsym (abfd, &sym))
9939 return FALSE;
9940 sym.st_value = s->vma;
9941 dest = dynsym + dynindx * bed->s->sizeof_sym;
9942 if (last_local < dynindx)
9943 last_local = dynindx;
9944 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
9945 }
9946 }
9947
9948 /* Write out the local dynsyms. */
9949 if (elf_hash_table (info)->dynlocal)
9950 {
9951 struct elf_link_local_dynamic_entry *e;
9952 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
9953 {
9954 asection *s;
9955 bfd_byte *dest;
9956
9957 sym.st_size = e->isym.st_size;
9958 sym.st_other = e->isym.st_other;
9959
9960 /* Copy the internal symbol as is.
9961 Note that we saved a word of storage and overwrote
9962 the original st_name with the dynstr_index. */
9963 sym = e->isym;
9964
9965 if (e->isym.st_shndx != SHN_UNDEF
9966 && (e->isym.st_shndx < SHN_LORESERVE
9967 || e->isym.st_shndx > SHN_HIRESERVE))
9968 {
9969 s = bfd_section_from_elf_index (e->input_bfd,
9970 e->isym.st_shndx);
9971
9972 sym.st_shndx =
9973 elf_section_data (s->output_section)->this_idx;
9974 if (! check_dynsym (abfd, &sym))
9975 return FALSE;
9976 sym.st_value = (s->output_section->vma
9977 + s->output_offset
9978 + e->isym.st_value);
9979 }
9980
9981 if (last_local < e->dynindx)
9982 last_local = e->dynindx;
9983
9984 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
9985 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
9986 }
9987 }
9988
9989 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
9990 last_local + 1;
9991 }
9992
9993 /* We get the global symbols from the hash table. */
9994 eoinfo.failed = FALSE;
9995 eoinfo.localsyms = FALSE;
9996 eoinfo.finfo = &finfo;
9997 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
9998 &eoinfo);
9999 if (eoinfo.failed)
10000 return FALSE;
10001
10002 /* If backend needs to output some symbols not present in the hash
10003 table, do it now. */
10004 if (bed->elf_backend_output_arch_syms)
10005 {
10006 typedef bfd_boolean (*out_sym_func)
10007 (void *, const char *, Elf_Internal_Sym *, asection *,
10008 struct elf_link_hash_entry *);
10009
10010 if (! ((*bed->elf_backend_output_arch_syms)
10011 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
10012 return FALSE;
10013 }
10014
10015 /* Flush all symbols to the file. */
10016 if (! elf_link_flush_output_syms (&finfo, bed))
10017 return FALSE;
10018
10019 /* Now we know the size of the symtab section. */
10020 off += symtab_hdr->sh_size;
10021
10022 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
10023 if (symtab_shndx_hdr->sh_name != 0)
10024 {
10025 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
10026 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
10027 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
10028 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
10029 symtab_shndx_hdr->sh_size = amt;
10030
10031 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
10032 off, TRUE);
10033
10034 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
10035 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
10036 return FALSE;
10037 }
10038
10039
10040 /* Finish up and write out the symbol string table (.strtab)
10041 section. */
10042 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
10043 /* sh_name was set in prep_headers. */
10044 symstrtab_hdr->sh_type = SHT_STRTAB;
10045 symstrtab_hdr->sh_flags = 0;
10046 symstrtab_hdr->sh_addr = 0;
10047 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
10048 symstrtab_hdr->sh_entsize = 0;
10049 symstrtab_hdr->sh_link = 0;
10050 symstrtab_hdr->sh_info = 0;
10051 /* sh_offset is set just below. */
10052 symstrtab_hdr->sh_addralign = 1;
10053
10054 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
10055 elf_tdata (abfd)->next_file_pos = off;
10056
10057 if (bfd_get_symcount (abfd) > 0)
10058 {
10059 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
10060 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
10061 return FALSE;
10062 }
10063
10064 /* Adjust the relocs to have the correct symbol indices. */
10065 for (o = abfd->sections; o != NULL; o = o->next)
10066 {
10067 if ((o->flags & SEC_RELOC) == 0)
10068 continue;
10069
10070 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
10071 elf_section_data (o)->rel_count,
10072 elf_section_data (o)->rel_hashes);
10073 if (elf_section_data (o)->rel_hdr2 != NULL)
10074 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
10075 elf_section_data (o)->rel_count2,
10076 (elf_section_data (o)->rel_hashes
10077 + elf_section_data (o)->rel_count));
10078
10079 /* Set the reloc_count field to 0 to prevent write_relocs from
10080 trying to swap the relocs out itself. */
10081 o->reloc_count = 0;
10082 }
10083
10084 if (dynamic && info->combreloc && dynobj != NULL)
10085 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
10086
10087 /* If we are linking against a dynamic object, or generating a
10088 shared library, finish up the dynamic linking information. */
10089 if (dynamic)
10090 {
10091 bfd_byte *dyncon, *dynconend;
10092
10093 /* Fix up .dynamic entries. */
10094 o = bfd_get_section_by_name (dynobj, ".dynamic");
10095 BFD_ASSERT (o != NULL);
10096
10097 dyncon = o->contents;
10098 dynconend = o->contents + o->size;
10099 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
10100 {
10101 Elf_Internal_Dyn dyn;
10102 const char *name;
10103 unsigned int type;
10104
10105 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
10106
10107 switch (dyn.d_tag)
10108 {
10109 default:
10110 continue;
10111 case DT_NULL:
10112 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
10113 {
10114 switch (elf_section_data (reldyn)->this_hdr.sh_type)
10115 {
10116 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
10117 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
10118 default: continue;
10119 }
10120 dyn.d_un.d_val = relativecount;
10121 relativecount = 0;
10122 break;
10123 }
10124 continue;
10125
10126 case DT_INIT:
10127 name = info->init_function;
10128 goto get_sym;
10129 case DT_FINI:
10130 name = info->fini_function;
10131 get_sym:
10132 {
10133 struct elf_link_hash_entry *h;
10134
10135 h = elf_link_hash_lookup (elf_hash_table (info), name,
10136 FALSE, FALSE, TRUE);
10137 if (h != NULL
10138 && (h->root.type == bfd_link_hash_defined
10139 || h->root.type == bfd_link_hash_defweak))
10140 {
10141 dyn.d_un.d_val = h->root.u.def.value;
10142 o = h->root.u.def.section;
10143 if (o->output_section != NULL)
10144 dyn.d_un.d_val += (o->output_section->vma
10145 + o->output_offset);
10146 else
10147 {
10148 /* The symbol is imported from another shared
10149 library and does not apply to this one. */
10150 dyn.d_un.d_val = 0;
10151 }
10152 break;
10153 }
10154 }
10155 continue;
10156
10157 case DT_PREINIT_ARRAYSZ:
10158 name = ".preinit_array";
10159 goto get_size;
10160 case DT_INIT_ARRAYSZ:
10161 name = ".init_array";
10162 goto get_size;
10163 case DT_FINI_ARRAYSZ:
10164 name = ".fini_array";
10165 get_size:
10166 o = bfd_get_section_by_name (abfd, name);
10167 if (o == NULL)
10168 {
10169 (*_bfd_error_handler)
10170 (_("%B: could not find output section %s"), abfd, name);
10171 goto error_return;
10172 }
10173 if (o->size == 0)
10174 (*_bfd_error_handler)
10175 (_("warning: %s section has zero size"), name);
10176 dyn.d_un.d_val = o->size;
10177 break;
10178
10179 case DT_PREINIT_ARRAY:
10180 name = ".preinit_array";
10181 goto get_vma;
10182 case DT_INIT_ARRAY:
10183 name = ".init_array";
10184 goto get_vma;
10185 case DT_FINI_ARRAY:
10186 name = ".fini_array";
10187 goto get_vma;
10188
10189 case DT_HASH:
10190 name = ".hash";
10191 goto get_vma;
10192 case DT_GNU_HASH:
10193 name = ".gnu.hash";
10194 goto get_vma;
10195 case DT_STRTAB:
10196 name = ".dynstr";
10197 goto get_vma;
10198 case DT_SYMTAB:
10199 name = ".dynsym";
10200 goto get_vma;
10201 case DT_VERDEF:
10202 name = ".gnu.version_d";
10203 goto get_vma;
10204 case DT_VERNEED:
10205 name = ".gnu.version_r";
10206 goto get_vma;
10207 case DT_VERSYM:
10208 name = ".gnu.version";
10209 get_vma:
10210 o = bfd_get_section_by_name (abfd, name);
10211 if (o == NULL)
10212 {
10213 (*_bfd_error_handler)
10214 (_("%B: could not find output section %s"), abfd, name);
10215 goto error_return;
10216 }
10217 dyn.d_un.d_ptr = o->vma;
10218 break;
10219
10220 case DT_REL:
10221 case DT_RELA:
10222 case DT_RELSZ:
10223 case DT_RELASZ:
10224 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
10225 type = SHT_REL;
10226 else
10227 type = SHT_RELA;
10228 dyn.d_un.d_val = 0;
10229 for (i = 1; i < elf_numsections (abfd); i++)
10230 {
10231 Elf_Internal_Shdr *hdr;
10232
10233 hdr = elf_elfsections (abfd)[i];
10234 if (hdr->sh_type == type
10235 && (hdr->sh_flags & SHF_ALLOC) != 0)
10236 {
10237 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
10238 dyn.d_un.d_val += hdr->sh_size;
10239 else
10240 {
10241 if (dyn.d_un.d_val == 0
10242 || hdr->sh_addr < dyn.d_un.d_val)
10243 dyn.d_un.d_val = hdr->sh_addr;
10244 }
10245 }
10246 }
10247 break;
10248 }
10249 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
10250 }
10251 }
10252
10253 /* If we have created any dynamic sections, then output them. */
10254 if (dynobj != NULL)
10255 {
10256 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
10257 goto error_return;
10258
10259 /* Check for DT_TEXTREL (late, in case the backend removes it). */
10260 if (info->warn_shared_textrel && info->shared)
10261 {
10262 bfd_byte *dyncon, *dynconend;
10263
10264 /* Fix up .dynamic entries. */
10265 o = bfd_get_section_by_name (dynobj, ".dynamic");
10266 BFD_ASSERT (o != NULL);
10267
10268 dyncon = o->contents;
10269 dynconend = o->contents + o->size;
10270 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
10271 {
10272 Elf_Internal_Dyn dyn;
10273
10274 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
10275
10276 if (dyn.d_tag == DT_TEXTREL)
10277 {
10278 info->callbacks->einfo
10279 (_("%P: warning: creating a DT_TEXTREL in a shared object.\n"));
10280 break;
10281 }
10282 }
10283 }
10284
10285 for (o = dynobj->sections; o != NULL; o = o->next)
10286 {
10287 if ((o->flags & SEC_HAS_CONTENTS) == 0
10288 || o->size == 0
10289 || o->output_section == bfd_abs_section_ptr)
10290 continue;
10291 if ((o->flags & SEC_LINKER_CREATED) == 0)
10292 {
10293 /* At this point, we are only interested in sections
10294 created by _bfd_elf_link_create_dynamic_sections. */
10295 continue;
10296 }
10297 if (elf_hash_table (info)->stab_info.stabstr == o)
10298 continue;
10299 if (elf_hash_table (info)->eh_info.hdr_sec == o)
10300 continue;
10301 if ((elf_section_data (o->output_section)->this_hdr.sh_type
10302 != SHT_STRTAB)
10303 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
10304 {
10305 if (! bfd_set_section_contents (abfd, o->output_section,
10306 o->contents,
10307 (file_ptr) o->output_offset,
10308 o->size))
10309 goto error_return;
10310 }
10311 else
10312 {
10313 /* The contents of the .dynstr section are actually in a
10314 stringtab. */
10315 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
10316 if (bfd_seek (abfd, off, SEEK_SET) != 0
10317 || ! _bfd_elf_strtab_emit (abfd,
10318 elf_hash_table (info)->dynstr))
10319 goto error_return;
10320 }
10321 }
10322 }
10323
10324 if (info->relocatable)
10325 {
10326 bfd_boolean failed = FALSE;
10327
10328 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
10329 if (failed)
10330 goto error_return;
10331 }
10332
10333 /* If we have optimized stabs strings, output them. */
10334 if (elf_hash_table (info)->stab_info.stabstr != NULL)
10335 {
10336 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
10337 goto error_return;
10338 }
10339
10340 if (info->eh_frame_hdr)
10341 {
10342 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
10343 goto error_return;
10344 }
10345
10346 if (finfo.symstrtab != NULL)
10347 _bfd_stringtab_free (finfo.symstrtab);
10348 if (finfo.contents != NULL)
10349 free (finfo.contents);
10350 if (finfo.external_relocs != NULL)
10351 free (finfo.external_relocs);
10352 if (finfo.internal_relocs != NULL)
10353 free (finfo.internal_relocs);
10354 if (finfo.external_syms != NULL)
10355 free (finfo.external_syms);
10356 if (finfo.locsym_shndx != NULL)
10357 free (finfo.locsym_shndx);
10358 if (finfo.internal_syms != NULL)
10359 free (finfo.internal_syms);
10360 if (finfo.indices != NULL)
10361 free (finfo.indices);
10362 if (finfo.sections != NULL)
10363 free (finfo.sections);
10364 if (finfo.symbuf != NULL)
10365 free (finfo.symbuf);
10366 if (finfo.symshndxbuf != NULL)
10367 free (finfo.symshndxbuf);
10368 for (o = abfd->sections; o != NULL; o = o->next)
10369 {
10370 if ((o->flags & SEC_RELOC) != 0
10371 && elf_section_data (o)->rel_hashes != NULL)
10372 free (elf_section_data (o)->rel_hashes);
10373 }
10374
10375 elf_tdata (abfd)->linker = TRUE;
10376
10377 if (attr_section)
10378 {
10379 bfd_byte *contents = bfd_malloc (attr_size);
10380 if (contents == NULL)
10381 goto error_return;
10382 bfd_elf_set_obj_attr_contents (abfd, contents, attr_size);
10383 bfd_set_section_contents (abfd, attr_section, contents, 0, attr_size);
10384 free (contents);
10385 }
10386
10387 return TRUE;
10388
10389 error_return:
10390 if (finfo.symstrtab != NULL)
10391 _bfd_stringtab_free (finfo.symstrtab);
10392 if (finfo.contents != NULL)
10393 free (finfo.contents);
10394 if (finfo.external_relocs != NULL)
10395 free (finfo.external_relocs);
10396 if (finfo.internal_relocs != NULL)
10397 free (finfo.internal_relocs);
10398 if (finfo.external_syms != NULL)
10399 free (finfo.external_syms);
10400 if (finfo.locsym_shndx != NULL)
10401 free (finfo.locsym_shndx);
10402 if (finfo.internal_syms != NULL)
10403 free (finfo.internal_syms);
10404 if (finfo.indices != NULL)
10405 free (finfo.indices);
10406 if (finfo.sections != NULL)
10407 free (finfo.sections);
10408 if (finfo.symbuf != NULL)
10409 free (finfo.symbuf);
10410 if (finfo.symshndxbuf != NULL)
10411 free (finfo.symshndxbuf);
10412 for (o = abfd->sections; o != NULL; o = o->next)
10413 {
10414 if ((o->flags & SEC_RELOC) != 0
10415 && elf_section_data (o)->rel_hashes != NULL)
10416 free (elf_section_data (o)->rel_hashes);
10417 }
10418
10419 return FALSE;
10420 }
10421
10422 /* Garbage collect unused sections. */
10423
10424 /* Default gc_mark_hook. */
10425
10426 asection *
_bfd_elf_gc_mark_hook(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)10427 _bfd_elf_gc_mark_hook (asection *sec,
10428 struct bfd_link_info *info ATTRIBUTE_UNUSED,
10429 Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
10430 struct elf_link_hash_entry *h,
10431 Elf_Internal_Sym *sym)
10432 {
10433 if (h != NULL)
10434 {
10435 switch (h->root.type)
10436 {
10437 case bfd_link_hash_defined:
10438 case bfd_link_hash_defweak:
10439 return h->root.u.def.section;
10440
10441 case bfd_link_hash_common:
10442 return h->root.u.c.p->section;
10443
10444 default:
10445 break;
10446 }
10447 }
10448 else
10449 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
10450
10451 return NULL;
10452 }
10453
10454 /* The mark phase of garbage collection. For a given section, mark
10455 it and any sections in this section's group, and all the sections
10456 which define symbols to which it refers. */
10457
10458 bfd_boolean
_bfd_elf_gc_mark(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook)10459 _bfd_elf_gc_mark (struct bfd_link_info *info,
10460 asection *sec,
10461 elf_gc_mark_hook_fn gc_mark_hook)
10462 {
10463 bfd_boolean ret;
10464 bfd_boolean is_eh;
10465 asection *group_sec;
10466
10467 sec->gc_mark = 1;
10468
10469 /* Mark all the sections in the group. */
10470 group_sec = elf_section_data (sec)->next_in_group;
10471 if (group_sec && !group_sec->gc_mark)
10472 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
10473 return FALSE;
10474
10475 /* Look through the section relocs. */
10476 ret = TRUE;
10477 is_eh = strcmp (sec->name, ".eh_frame") == 0;
10478 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
10479 {
10480 Elf_Internal_Rela *relstart, *rel, *relend;
10481 Elf_Internal_Shdr *symtab_hdr;
10482 struct elf_link_hash_entry **sym_hashes;
10483 size_t nlocsyms;
10484 size_t extsymoff;
10485 bfd *input_bfd = sec->owner;
10486 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
10487 Elf_Internal_Sym *isym = NULL;
10488 int r_sym_shift;
10489
10490 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
10491 sym_hashes = elf_sym_hashes (input_bfd);
10492
10493 /* Read the local symbols. */
10494 if (elf_bad_symtab (input_bfd))
10495 {
10496 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
10497 extsymoff = 0;
10498 }
10499 else
10500 extsymoff = nlocsyms = symtab_hdr->sh_info;
10501
10502 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
10503 if (isym == NULL && nlocsyms != 0)
10504 {
10505 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
10506 NULL, NULL, NULL);
10507 if (isym == NULL)
10508 return FALSE;
10509 }
10510
10511 /* Read the relocations. */
10512 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
10513 info->keep_memory);
10514 if (relstart == NULL)
10515 {
10516 ret = FALSE;
10517 goto out1;
10518 }
10519 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
10520
10521 if (bed->s->arch_size == 32)
10522 r_sym_shift = 8;
10523 else
10524 r_sym_shift = 32;
10525
10526 for (rel = relstart; rel < relend; rel++)
10527 {
10528 unsigned long r_symndx;
10529 asection *rsec;
10530 struct elf_link_hash_entry *h;
10531
10532 r_symndx = rel->r_info >> r_sym_shift;
10533 if (r_symndx == 0)
10534 continue;
10535
10536 if (r_symndx >= nlocsyms
10537 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
10538 {
10539 h = sym_hashes[r_symndx - extsymoff];
10540 while (h->root.type == bfd_link_hash_indirect
10541 || h->root.type == bfd_link_hash_warning)
10542 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10543 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
10544 }
10545 else
10546 {
10547 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
10548 }
10549
10550 if (rsec && !rsec->gc_mark)
10551 {
10552 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
10553 rsec->gc_mark = 1;
10554 else if (is_eh)
10555 rsec->gc_mark_from_eh = 1;
10556 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
10557 {
10558 ret = FALSE;
10559 goto out2;
10560 }
10561 }
10562 }
10563
10564 out2:
10565 if (elf_section_data (sec)->relocs != relstart)
10566 free (relstart);
10567 out1:
10568 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
10569 {
10570 if (! info->keep_memory)
10571 free (isym);
10572 else
10573 symtab_hdr->contents = (unsigned char *) isym;
10574 }
10575 }
10576
10577 return ret;
10578 }
10579
10580 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
10581
10582 struct elf_gc_sweep_symbol_info
10583 {
10584 struct bfd_link_info *info;
10585 void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
10586 bfd_boolean);
10587 };
10588
10589 static bfd_boolean
elf_gc_sweep_symbol(struct elf_link_hash_entry * h,void * data)10590 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
10591 {
10592 if (h->root.type == bfd_link_hash_warning)
10593 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10594
10595 if ((h->root.type == bfd_link_hash_defined
10596 || h->root.type == bfd_link_hash_defweak)
10597 && !h->root.u.def.section->gc_mark
10598 && !(h->root.u.def.section->owner->flags & DYNAMIC))
10599 {
10600 struct elf_gc_sweep_symbol_info *inf = data;
10601 (*inf->hide_symbol) (inf->info, h, TRUE);
10602 }
10603
10604 return TRUE;
10605 }
10606
10607 /* The sweep phase of garbage collection. Remove all garbage sections. */
10608
10609 typedef bfd_boolean (*gc_sweep_hook_fn)
10610 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
10611
10612 static bfd_boolean
elf_gc_sweep(bfd * abfd,struct bfd_link_info * info)10613 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
10614 {
10615 bfd *sub;
10616 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10617 gc_sweep_hook_fn gc_sweep_hook = bed->gc_sweep_hook;
10618 unsigned long section_sym_count;
10619 struct elf_gc_sweep_symbol_info sweep_info;
10620
10621 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
10622 {
10623 asection *o;
10624
10625 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
10626 continue;
10627
10628 for (o = sub->sections; o != NULL; o = o->next)
10629 {
10630 /* Keep debug and special sections. */
10631 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
10632 || elf_section_data (o)->this_hdr.sh_type == SHT_NOTE
10633 || (o->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0)
10634 o->gc_mark = 1;
10635
10636 if (o->gc_mark)
10637 continue;
10638
10639 /* Skip sweeping sections already excluded. */
10640 if (o->flags & SEC_EXCLUDE)
10641 continue;
10642
10643 /* Since this is early in the link process, it is simple
10644 to remove a section from the output. */
10645 o->flags |= SEC_EXCLUDE;
10646
10647 if (info->print_gc_sections && o->size != 0)
10648 _bfd_error_handler (_("Removing unused section '%s' in file '%B'"), sub, o->name);
10649
10650 /* But we also have to update some of the relocation
10651 info we collected before. */
10652 if (gc_sweep_hook
10653 && (o->flags & SEC_RELOC) != 0
10654 && o->reloc_count > 0
10655 && !bfd_is_abs_section (o->output_section))
10656 {
10657 Elf_Internal_Rela *internal_relocs;
10658 bfd_boolean r;
10659
10660 internal_relocs
10661 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
10662 info->keep_memory);
10663 if (internal_relocs == NULL)
10664 return FALSE;
10665
10666 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
10667
10668 if (elf_section_data (o)->relocs != internal_relocs)
10669 free (internal_relocs);
10670
10671 if (!r)
10672 return FALSE;
10673 }
10674 }
10675 }
10676
10677 /* Remove the symbols that were in the swept sections from the dynamic
10678 symbol table. GCFIXME: Anyone know how to get them out of the
10679 static symbol table as well? */
10680 sweep_info.info = info;
10681 sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
10682 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
10683 &sweep_info);
10684
10685 _bfd_elf_link_renumber_dynsyms (abfd, info, §ion_sym_count);
10686 return TRUE;
10687 }
10688
10689 /* Propagate collected vtable information. This is called through
10690 elf_link_hash_traverse. */
10691
10692 static bfd_boolean
elf_gc_propagate_vtable_entries_used(struct elf_link_hash_entry * h,void * okp)10693 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
10694 {
10695 if (h->root.type == bfd_link_hash_warning)
10696 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10697
10698 /* Those that are not vtables. */
10699 if (h->vtable == NULL || h->vtable->parent == NULL)
10700 return TRUE;
10701
10702 /* Those vtables that do not have parents, we cannot merge. */
10703 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
10704 return TRUE;
10705
10706 /* If we've already been done, exit. */
10707 if (h->vtable->used && h->vtable->used[-1])
10708 return TRUE;
10709
10710 /* Make sure the parent's table is up to date. */
10711 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
10712
10713 if (h->vtable->used == NULL)
10714 {
10715 /* None of this table's entries were referenced. Re-use the
10716 parent's table. */
10717 h->vtable->used = h->vtable->parent->vtable->used;
10718 h->vtable->size = h->vtable->parent->vtable->size;
10719 }
10720 else
10721 {
10722 size_t n;
10723 bfd_boolean *cu, *pu;
10724
10725 /* Or the parent's entries into ours. */
10726 cu = h->vtable->used;
10727 cu[-1] = TRUE;
10728 pu = h->vtable->parent->vtable->used;
10729 if (pu != NULL)
10730 {
10731 const struct elf_backend_data *bed;
10732 unsigned int log_file_align;
10733
10734 bed = get_elf_backend_data (h->root.u.def.section->owner);
10735 log_file_align = bed->s->log_file_align;
10736 n = h->vtable->parent->vtable->size >> log_file_align;
10737 while (n--)
10738 {
10739 if (*pu)
10740 *cu = TRUE;
10741 pu++;
10742 cu++;
10743 }
10744 }
10745 }
10746
10747 return TRUE;
10748 }
10749
10750 static bfd_boolean
elf_gc_smash_unused_vtentry_relocs(struct elf_link_hash_entry * h,void * okp)10751 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
10752 {
10753 asection *sec;
10754 bfd_vma hstart, hend;
10755 Elf_Internal_Rela *relstart, *relend, *rel;
10756 const struct elf_backend_data *bed;
10757 unsigned int log_file_align;
10758
10759 if (h->root.type == bfd_link_hash_warning)
10760 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10761
10762 /* Take care of both those symbols that do not describe vtables as
10763 well as those that are not loaded. */
10764 if (h->vtable == NULL || h->vtable->parent == NULL)
10765 return TRUE;
10766
10767 BFD_ASSERT (h->root.type == bfd_link_hash_defined
10768 || h->root.type == bfd_link_hash_defweak);
10769
10770 sec = h->root.u.def.section;
10771 hstart = h->root.u.def.value;
10772 hend = hstart + h->size;
10773
10774 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
10775 if (!relstart)
10776 return *(bfd_boolean *) okp = FALSE;
10777 bed = get_elf_backend_data (sec->owner);
10778 log_file_align = bed->s->log_file_align;
10779
10780 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
10781
10782 for (rel = relstart; rel < relend; ++rel)
10783 if (rel->r_offset >= hstart && rel->r_offset < hend)
10784 {
10785 /* If the entry is in use, do nothing. */
10786 if (h->vtable->used
10787 && (rel->r_offset - hstart) < h->vtable->size)
10788 {
10789 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
10790 if (h->vtable->used[entry])
10791 continue;
10792 }
10793 /* Otherwise, kill it. */
10794 rel->r_offset = rel->r_info = rel->r_addend = 0;
10795 }
10796
10797 return TRUE;
10798 }
10799
10800 /* Mark sections containing dynamically referenced symbols. When
10801 building shared libraries, we must assume that any visible symbol is
10802 referenced. */
10803
10804 bfd_boolean
bfd_elf_gc_mark_dynamic_ref_symbol(struct elf_link_hash_entry * h,void * inf)10805 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
10806 {
10807 struct bfd_link_info *info = (struct bfd_link_info *) inf;
10808
10809 if (h->root.type == bfd_link_hash_warning)
10810 h = (struct elf_link_hash_entry *) h->root.u.i.link;
10811
10812 if ((h->root.type == bfd_link_hash_defined
10813 || h->root.type == bfd_link_hash_defweak)
10814 && (h->ref_dynamic
10815 || (!info->executable
10816 && h->def_regular
10817 && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
10818 && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN)))
10819 h->root.u.def.section->flags |= SEC_KEEP;
10820
10821 return TRUE;
10822 }
10823
10824 /* Do mark and sweep of unused sections. */
10825
10826 bfd_boolean
bfd_elf_gc_sections(bfd * abfd,struct bfd_link_info * info)10827 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
10828 {
10829 bfd_boolean ok = TRUE;
10830 bfd *sub;
10831 elf_gc_mark_hook_fn gc_mark_hook;
10832 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10833
10834 if (!bed->can_gc_sections
10835 || info->relocatable
10836 || info->emitrelocations
10837 || !is_elf_hash_table (info->hash))
10838 {
10839 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
10840 return TRUE;
10841 }
10842
10843 /* Apply transitive closure to the vtable entry usage info. */
10844 elf_link_hash_traverse (elf_hash_table (info),
10845 elf_gc_propagate_vtable_entries_used,
10846 &ok);
10847 if (!ok)
10848 return FALSE;
10849
10850 /* Kill the vtable relocations that were not used. */
10851 elf_link_hash_traverse (elf_hash_table (info),
10852 elf_gc_smash_unused_vtentry_relocs,
10853 &ok);
10854 if (!ok)
10855 return FALSE;
10856
10857 /* Mark dynamically referenced symbols. */
10858 if (elf_hash_table (info)->dynamic_sections_created)
10859 elf_link_hash_traverse (elf_hash_table (info),
10860 bed->gc_mark_dynamic_ref,
10861 info);
10862
10863 /* Grovel through relocs to find out who stays ... */
10864 gc_mark_hook = bed->gc_mark_hook;
10865 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
10866 {
10867 asection *o;
10868
10869 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
10870 continue;
10871
10872 for (o = sub->sections; o != NULL; o = o->next)
10873 if ((o->flags & (SEC_EXCLUDE | SEC_KEEP)) == SEC_KEEP && !o->gc_mark)
10874 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
10875 return FALSE;
10876 }
10877
10878 /* Allow the backend to mark additional target specific sections. */
10879 if (bed->gc_mark_extra_sections)
10880 bed->gc_mark_extra_sections(info, gc_mark_hook);
10881
10882 /* ... again for sections marked from eh_frame. */
10883 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
10884 {
10885 asection *o;
10886
10887 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
10888 continue;
10889
10890 /* Keep .gcc_except_table.* if the associated .text.* (or the
10891 associated .gnu.linkonce.t.* if .text.* doesn't exist) is
10892 marked. This isn't very nice, but the proper solution,
10893 splitting .eh_frame up and using comdat doesn't pan out
10894 easily due to needing special relocs to handle the
10895 difference of two symbols in separate sections.
10896 Don't keep code sections referenced by .eh_frame. */
10897 #define TEXT_PREFIX ".text."
10898 #define TEXT_PREFIX2 ".gnu.linkonce.t."
10899 #define GCC_EXCEPT_TABLE_PREFIX ".gcc_except_table."
10900 for (o = sub->sections; o != NULL; o = o->next)
10901 if (!o->gc_mark && o->gc_mark_from_eh && (o->flags & SEC_CODE) == 0)
10902 {
10903 if (CONST_STRNEQ (o->name, GCC_EXCEPT_TABLE_PREFIX))
10904 {
10905 char *fn_name;
10906 const char *sec_name;
10907 asection *fn_text;
10908 unsigned o_name_prefix_len , fn_name_prefix_len, tmp;
10909
10910 o_name_prefix_len = strlen (GCC_EXCEPT_TABLE_PREFIX);
10911 sec_name = o->name + o_name_prefix_len;
10912 fn_name_prefix_len = strlen (TEXT_PREFIX);
10913 tmp = strlen (TEXT_PREFIX2);
10914 if (tmp > fn_name_prefix_len)
10915 fn_name_prefix_len = tmp;
10916 fn_name
10917 = bfd_malloc (fn_name_prefix_len + strlen (sec_name) + 1);
10918 if (fn_name == NULL)
10919 return FALSE;
10920
10921 /* Try the first prefix. */
10922 sprintf (fn_name, "%s%s", TEXT_PREFIX, sec_name);
10923 fn_text = bfd_get_section_by_name (sub, fn_name);
10924
10925 /* Try the second prefix. */
10926 if (fn_text == NULL)
10927 {
10928 sprintf (fn_name, "%s%s", TEXT_PREFIX2, sec_name);
10929 fn_text = bfd_get_section_by_name (sub, fn_name);
10930 }
10931
10932 free (fn_name);
10933 if (fn_text == NULL || !fn_text->gc_mark)
10934 continue;
10935 }
10936
10937 /* If not using specially named exception table section,
10938 then keep whatever we are using. */
10939 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
10940 return FALSE;
10941 }
10942 }
10943
10944 /* ... and mark SEC_EXCLUDE for those that go. */
10945 return elf_gc_sweep (abfd, info);
10946 }
10947
10948 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
10949
10950 bfd_boolean
bfd_elf_gc_record_vtinherit(bfd * abfd,asection * sec,struct elf_link_hash_entry * h,bfd_vma offset)10951 bfd_elf_gc_record_vtinherit (bfd *abfd,
10952 asection *sec,
10953 struct elf_link_hash_entry *h,
10954 bfd_vma offset)
10955 {
10956 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
10957 struct elf_link_hash_entry **search, *child;
10958 bfd_size_type extsymcount;
10959 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
10960
10961 /* The sh_info field of the symtab header tells us where the
10962 external symbols start. We don't care about the local symbols at
10963 this point. */
10964 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
10965 if (!elf_bad_symtab (abfd))
10966 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
10967
10968 sym_hashes = elf_sym_hashes (abfd);
10969 sym_hashes_end = sym_hashes + extsymcount;
10970
10971 /* Hunt down the child symbol, which is in this section at the same
10972 offset as the relocation. */
10973 for (search = sym_hashes; search != sym_hashes_end; ++search)
10974 {
10975 if ((child = *search) != NULL
10976 && (child->root.type == bfd_link_hash_defined
10977 || child->root.type == bfd_link_hash_defweak)
10978 && child->root.u.def.section == sec
10979 && child->root.u.def.value == offset)
10980 goto win;
10981 }
10982
10983 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
10984 abfd, sec, (unsigned long) offset);
10985 bfd_set_error (bfd_error_invalid_operation);
10986 return FALSE;
10987
10988 win:
10989 if (!child->vtable)
10990 {
10991 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
10992 if (!child->vtable)
10993 return FALSE;
10994 }
10995 if (!h)
10996 {
10997 /* This *should* only be the absolute section. It could potentially
10998 be that someone has defined a non-global vtable though, which
10999 would be bad. It isn't worth paging in the local symbols to be
11000 sure though; that case should simply be handled by the assembler. */
11001
11002 child->vtable->parent = (struct elf_link_hash_entry *) -1;
11003 }
11004 else
11005 child->vtable->parent = h;
11006
11007 return TRUE;
11008 }
11009
11010 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
11011
11012 bfd_boolean
bfd_elf_gc_record_vtentry(bfd * abfd ATTRIBUTE_UNUSED,asection * sec ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,bfd_vma addend)11013 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
11014 asection *sec ATTRIBUTE_UNUSED,
11015 struct elf_link_hash_entry *h,
11016 bfd_vma addend)
11017 {
11018 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11019 unsigned int log_file_align = bed->s->log_file_align;
11020
11021 if (!h->vtable)
11022 {
11023 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
11024 if (!h->vtable)
11025 return FALSE;
11026 }
11027
11028 if (addend >= h->vtable->size)
11029 {
11030 size_t size, bytes, file_align;
11031 bfd_boolean *ptr = h->vtable->used;
11032
11033 /* While the symbol is undefined, we have to be prepared to handle
11034 a zero size. */
11035 file_align = 1 << log_file_align;
11036 if (h->root.type == bfd_link_hash_undefined)
11037 size = addend + file_align;
11038 else
11039 {
11040 size = h->size;
11041 if (addend >= size)
11042 {
11043 /* Oops! We've got a reference past the defined end of
11044 the table. This is probably a bug -- shall we warn? */
11045 size = addend + file_align;
11046 }
11047 }
11048 size = (size + file_align - 1) & -file_align;
11049
11050 /* Allocate one extra entry for use as a "done" flag for the
11051 consolidation pass. */
11052 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
11053
11054 if (ptr)
11055 {
11056 ptr = bfd_realloc (ptr - 1, bytes);
11057
11058 if (ptr != NULL)
11059 {
11060 size_t oldbytes;
11061
11062 oldbytes = (((h->vtable->size >> log_file_align) + 1)
11063 * sizeof (bfd_boolean));
11064 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
11065 }
11066 }
11067 else
11068 ptr = bfd_zmalloc (bytes);
11069
11070 if (ptr == NULL)
11071 return FALSE;
11072
11073 /* And arrange for that done flag to be at index -1. */
11074 h->vtable->used = ptr + 1;
11075 h->vtable->size = size;
11076 }
11077
11078 h->vtable->used[addend >> log_file_align] = TRUE;
11079
11080 return TRUE;
11081 }
11082
11083 struct alloc_got_off_arg {
11084 bfd_vma gotoff;
11085 unsigned int got_elt_size;
11086 };
11087
11088 /* We need a special top-level link routine to convert got reference counts
11089 to real got offsets. */
11090
11091 static bfd_boolean
elf_gc_allocate_got_offsets(struct elf_link_hash_entry * h,void * arg)11092 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
11093 {
11094 struct alloc_got_off_arg *gofarg = arg;
11095
11096 if (h->root.type == bfd_link_hash_warning)
11097 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11098
11099 if (h->got.refcount > 0)
11100 {
11101 h->got.offset = gofarg->gotoff;
11102 gofarg->gotoff += gofarg->got_elt_size;
11103 }
11104 else
11105 h->got.offset = (bfd_vma) -1;
11106
11107 return TRUE;
11108 }
11109
11110 /* And an accompanying bit to work out final got entry offsets once
11111 we're done. Should be called from final_link. */
11112
11113 bfd_boolean
bfd_elf_gc_common_finalize_got_offsets(bfd * abfd,struct bfd_link_info * info)11114 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
11115 struct bfd_link_info *info)
11116 {
11117 bfd *i;
11118 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
11119 bfd_vma gotoff;
11120 unsigned int got_elt_size = bed->s->arch_size / 8;
11121 struct alloc_got_off_arg gofarg;
11122
11123 if (! is_elf_hash_table (info->hash))
11124 return FALSE;
11125
11126 /* The GOT offset is relative to the .got section, but the GOT header is
11127 put into the .got.plt section, if the backend uses it. */
11128 if (bed->want_got_plt)
11129 gotoff = 0;
11130 else
11131 gotoff = bed->got_header_size;
11132
11133 /* Do the local .got entries first. */
11134 for (i = info->input_bfds; i; i = i->link_next)
11135 {
11136 bfd_signed_vma *local_got;
11137 bfd_size_type j, locsymcount;
11138 Elf_Internal_Shdr *symtab_hdr;
11139
11140 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
11141 continue;
11142
11143 local_got = elf_local_got_refcounts (i);
11144 if (!local_got)
11145 continue;
11146
11147 symtab_hdr = &elf_tdata (i)->symtab_hdr;
11148 if (elf_bad_symtab (i))
11149 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
11150 else
11151 locsymcount = symtab_hdr->sh_info;
11152
11153 for (j = 0; j < locsymcount; ++j)
11154 {
11155 if (local_got[j] > 0)
11156 {
11157 local_got[j] = gotoff;
11158 gotoff += got_elt_size;
11159 }
11160 else
11161 local_got[j] = (bfd_vma) -1;
11162 }
11163 }
11164
11165 /* Then the global .got entries. .plt refcounts are handled by
11166 adjust_dynamic_symbol */
11167 gofarg.gotoff = gotoff;
11168 gofarg.got_elt_size = got_elt_size;
11169 elf_link_hash_traverse (elf_hash_table (info),
11170 elf_gc_allocate_got_offsets,
11171 &gofarg);
11172 return TRUE;
11173 }
11174
11175 /* Many folk need no more in the way of final link than this, once
11176 got entry reference counting is enabled. */
11177
11178 bfd_boolean
bfd_elf_gc_common_final_link(bfd * abfd,struct bfd_link_info * info)11179 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
11180 {
11181 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
11182 return FALSE;
11183
11184 /* Invoke the regular ELF backend linker to do all the work. */
11185 return bfd_elf_final_link (abfd, info);
11186 }
11187
11188 bfd_boolean
bfd_elf_reloc_symbol_deleted_p(bfd_vma offset,void * cookie)11189 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
11190 {
11191 struct elf_reloc_cookie *rcookie = cookie;
11192
11193 if (rcookie->bad_symtab)
11194 rcookie->rel = rcookie->rels;
11195
11196 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
11197 {
11198 unsigned long r_symndx;
11199
11200 if (! rcookie->bad_symtab)
11201 if (rcookie->rel->r_offset > offset)
11202 return FALSE;
11203 if (rcookie->rel->r_offset != offset)
11204 continue;
11205
11206 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
11207 if (r_symndx == SHN_UNDEF)
11208 return TRUE;
11209
11210 if (r_symndx >= rcookie->locsymcount
11211 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
11212 {
11213 struct elf_link_hash_entry *h;
11214
11215 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
11216
11217 while (h->root.type == bfd_link_hash_indirect
11218 || h->root.type == bfd_link_hash_warning)
11219 h = (struct elf_link_hash_entry *) h->root.u.i.link;
11220
11221 if ((h->root.type == bfd_link_hash_defined
11222 || h->root.type == bfd_link_hash_defweak)
11223 && elf_discarded_section (h->root.u.def.section))
11224 return TRUE;
11225 else
11226 return FALSE;
11227 }
11228 else
11229 {
11230 /* It's not a relocation against a global symbol,
11231 but it could be a relocation against a local
11232 symbol for a discarded section. */
11233 asection *isec;
11234 Elf_Internal_Sym *isym;
11235
11236 /* Need to: get the symbol; get the section. */
11237 isym = &rcookie->locsyms[r_symndx];
11238 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
11239 {
11240 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
11241 if (isec != NULL && elf_discarded_section (isec))
11242 return TRUE;
11243 }
11244 }
11245 return FALSE;
11246 }
11247 return FALSE;
11248 }
11249
11250 /* Discard unneeded references to discarded sections.
11251 Returns TRUE if any section's size was changed. */
11252 /* This function assumes that the relocations are in sorted order,
11253 which is true for all known assemblers. */
11254
11255 bfd_boolean
bfd_elf_discard_info(bfd * output_bfd,struct bfd_link_info * info)11256 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
11257 {
11258 struct elf_reloc_cookie cookie;
11259 asection *stab, *eh;
11260 Elf_Internal_Shdr *symtab_hdr;
11261 const struct elf_backend_data *bed;
11262 bfd *abfd;
11263 unsigned int count;
11264 bfd_boolean ret = FALSE;
11265
11266 if (info->traditional_format
11267 || !is_elf_hash_table (info->hash))
11268 return FALSE;
11269
11270 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
11271 {
11272 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
11273 continue;
11274
11275 bed = get_elf_backend_data (abfd);
11276
11277 if ((abfd->flags & DYNAMIC) != 0)
11278 continue;
11279
11280 eh = NULL;
11281 if (!info->relocatable)
11282 {
11283 eh = bfd_get_section_by_name (abfd, ".eh_frame");
11284 if (eh != NULL
11285 && (eh->size == 0
11286 || bfd_is_abs_section (eh->output_section)))
11287 eh = NULL;
11288 }
11289
11290 stab = bfd_get_section_by_name (abfd, ".stab");
11291 if (stab != NULL
11292 && (stab->size == 0
11293 || bfd_is_abs_section (stab->output_section)
11294 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
11295 stab = NULL;
11296
11297 if (stab == NULL
11298 && eh == NULL
11299 && bed->elf_backend_discard_info == NULL)
11300 continue;
11301
11302 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
11303 cookie.abfd = abfd;
11304 cookie.sym_hashes = elf_sym_hashes (abfd);
11305 cookie.bad_symtab = elf_bad_symtab (abfd);
11306 if (cookie.bad_symtab)
11307 {
11308 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
11309 cookie.extsymoff = 0;
11310 }
11311 else
11312 {
11313 cookie.locsymcount = symtab_hdr->sh_info;
11314 cookie.extsymoff = symtab_hdr->sh_info;
11315 }
11316
11317 if (bed->s->arch_size == 32)
11318 cookie.r_sym_shift = 8;
11319 else
11320 cookie.r_sym_shift = 32;
11321
11322 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
11323 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
11324 {
11325 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
11326 cookie.locsymcount, 0,
11327 NULL, NULL, NULL);
11328 if (cookie.locsyms == NULL)
11329 {
11330 info->callbacks->einfo (_("%P%X: can not read symbols: %E\n"));
11331 return FALSE;
11332 }
11333 }
11334
11335 if (stab != NULL)
11336 {
11337 cookie.rels = NULL;
11338 count = stab->reloc_count;
11339 if (count != 0)
11340 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
11341 info->keep_memory);
11342 if (cookie.rels != NULL)
11343 {
11344 cookie.rel = cookie.rels;
11345 cookie.relend = cookie.rels;
11346 cookie.relend += count * bed->s->int_rels_per_ext_rel;
11347 if (_bfd_discard_section_stabs (abfd, stab,
11348 elf_section_data (stab)->sec_info,
11349 bfd_elf_reloc_symbol_deleted_p,
11350 &cookie))
11351 ret = TRUE;
11352 if (elf_section_data (stab)->relocs != cookie.rels)
11353 free (cookie.rels);
11354 }
11355 }
11356
11357 if (eh != NULL)
11358 {
11359 cookie.rels = NULL;
11360 count = eh->reloc_count;
11361 if (count != 0)
11362 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
11363 info->keep_memory);
11364 cookie.rel = cookie.rels;
11365 cookie.relend = cookie.rels;
11366 if (cookie.rels != NULL)
11367 cookie.relend += count * bed->s->int_rels_per_ext_rel;
11368
11369 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
11370 bfd_elf_reloc_symbol_deleted_p,
11371 &cookie))
11372 ret = TRUE;
11373
11374 if (cookie.rels != NULL
11375 && elf_section_data (eh)->relocs != cookie.rels)
11376 free (cookie.rels);
11377 }
11378
11379 if (bed->elf_backend_discard_info != NULL
11380 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
11381 ret = TRUE;
11382
11383 if (cookie.locsyms != NULL
11384 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
11385 {
11386 if (! info->keep_memory)
11387 free (cookie.locsyms);
11388 else
11389 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
11390 }
11391 }
11392
11393 if (info->eh_frame_hdr
11394 && !info->relocatable
11395 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
11396 ret = TRUE;
11397
11398 return ret;
11399 }
11400
11401 void
_bfd_elf_section_already_linked(bfd * abfd,struct bfd_section * sec,struct bfd_link_info * info)11402 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section *sec,
11403 struct bfd_link_info *info)
11404 {
11405 flagword flags;
11406 const char *name, *p;
11407 struct bfd_section_already_linked *l;
11408 struct bfd_section_already_linked_hash_entry *already_linked_list;
11409
11410 if (sec->output_section == bfd_abs_section_ptr)
11411 return;
11412
11413 flags = sec->flags;
11414
11415 /* Return if it isn't a linkonce section. A comdat group section
11416 also has SEC_LINK_ONCE set. */
11417 if ((flags & SEC_LINK_ONCE) == 0)
11418 return;
11419
11420 /* Don't put group member sections on our list of already linked
11421 sections. They are handled as a group via their group section. */
11422 if (elf_sec_group (sec) != NULL)
11423 return;
11424
11425 /* FIXME: When doing a relocatable link, we may have trouble
11426 copying relocations in other sections that refer to local symbols
11427 in the section being discarded. Those relocations will have to
11428 be converted somehow; as of this writing I'm not sure that any of
11429 the backends handle that correctly.
11430
11431 It is tempting to instead not discard link once sections when
11432 doing a relocatable link (technically, they should be discarded
11433 whenever we are building constructors). However, that fails,
11434 because the linker winds up combining all the link once sections
11435 into a single large link once section, which defeats the purpose
11436 of having link once sections in the first place.
11437
11438 Also, not merging link once sections in a relocatable link
11439 causes trouble for MIPS ELF, which relies on link once semantics
11440 to handle the .reginfo section correctly. */
11441
11442 name = bfd_get_section_name (abfd, sec);
11443
11444 if (CONST_STRNEQ (name, ".gnu.linkonce.")
11445 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
11446 p++;
11447 else
11448 p = name;
11449
11450 already_linked_list = bfd_section_already_linked_table_lookup (p);
11451
11452 for (l = already_linked_list->entry; l != NULL; l = l->next)
11453 {
11454 /* We may have 2 different types of sections on the list: group
11455 sections and linkonce sections. Match like sections. */
11456 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
11457 && strcmp (name, l->sec->name) == 0
11458 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
11459 {
11460 /* The section has already been linked. See if we should
11461 issue a warning. */
11462 switch (flags & SEC_LINK_DUPLICATES)
11463 {
11464 default:
11465 abort ();
11466
11467 case SEC_LINK_DUPLICATES_DISCARD:
11468 break;
11469
11470 case SEC_LINK_DUPLICATES_ONE_ONLY:
11471 (*_bfd_error_handler)
11472 (_("%B: ignoring duplicate section `%A'"),
11473 abfd, sec);
11474 break;
11475
11476 case SEC_LINK_DUPLICATES_SAME_SIZE:
11477 if (sec->size != l->sec->size)
11478 (*_bfd_error_handler)
11479 (_("%B: duplicate section `%A' has different size"),
11480 abfd, sec);
11481 break;
11482
11483 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
11484 if (sec->size != l->sec->size)
11485 (*_bfd_error_handler)
11486 (_("%B: duplicate section `%A' has different size"),
11487 abfd, sec);
11488 else if (sec->size != 0)
11489 {
11490 bfd_byte *sec_contents, *l_sec_contents = NULL;
11491
11492 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
11493 (*_bfd_error_handler)
11494 (_("%B: warning: could not read contents of section `%A'"),
11495 abfd, sec);
11496 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
11497 &l_sec_contents))
11498 (*_bfd_error_handler)
11499 (_("%B: warning: could not read contents of section `%A'"),
11500 l->sec->owner, l->sec);
11501 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
11502 (*_bfd_error_handler)
11503 (_("%B: warning: duplicate section `%A' has different contents"),
11504 abfd, sec);
11505
11506 if (sec_contents)
11507 free (sec_contents);
11508 if (l_sec_contents)
11509 free (l_sec_contents);
11510 }
11511 break;
11512 }
11513
11514 /* Set the output_section field so that lang_add_section
11515 does not create a lang_input_section structure for this
11516 section. Since there might be a symbol in the section
11517 being discarded, we must retain a pointer to the section
11518 which we are really going to use. */
11519 sec->output_section = bfd_abs_section_ptr;
11520 sec->kept_section = l->sec;
11521
11522 if (flags & SEC_GROUP)
11523 {
11524 asection *first = elf_next_in_group (sec);
11525 asection *s = first;
11526
11527 while (s != NULL)
11528 {
11529 s->output_section = bfd_abs_section_ptr;
11530 /* Record which group discards it. */
11531 s->kept_section = l->sec;
11532 s = elf_next_in_group (s);
11533 /* These lists are circular. */
11534 if (s == first)
11535 break;
11536 }
11537 }
11538
11539 return;
11540 }
11541 }
11542
11543 /* A single member comdat group section may be discarded by a
11544 linkonce section and vice versa. */
11545
11546 if ((flags & SEC_GROUP) != 0)
11547 {
11548 asection *first = elf_next_in_group (sec);
11549
11550 if (first != NULL && elf_next_in_group (first) == first)
11551 /* Check this single member group against linkonce sections. */
11552 for (l = already_linked_list->entry; l != NULL; l = l->next)
11553 if ((l->sec->flags & SEC_GROUP) == 0
11554 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
11555 && bfd_elf_match_symbols_in_sections (l->sec, first, info))
11556 {
11557 first->output_section = bfd_abs_section_ptr;
11558 first->kept_section = l->sec;
11559 sec->output_section = bfd_abs_section_ptr;
11560 break;
11561 }
11562 }
11563 else
11564 /* Check this linkonce section against single member groups. */
11565 for (l = already_linked_list->entry; l != NULL; l = l->next)
11566 if (l->sec->flags & SEC_GROUP)
11567 {
11568 asection *first = elf_next_in_group (l->sec);
11569
11570 if (first != NULL
11571 && elf_next_in_group (first) == first
11572 && bfd_elf_match_symbols_in_sections (first, sec, info))
11573 {
11574 sec->output_section = bfd_abs_section_ptr;
11575 sec->kept_section = first;
11576 break;
11577 }
11578 }
11579
11580 /* This is the first section with this name. Record it. */
11581 bfd_section_already_linked_table_insert (already_linked_list, sec);
11582 }
11583
11584 bfd_boolean
_bfd_elf_common_definition(Elf_Internal_Sym * sym)11585 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
11586 {
11587 return sym->st_shndx == SHN_COMMON;
11588 }
11589
11590 unsigned int
_bfd_elf_common_section_index(asection * sec ATTRIBUTE_UNUSED)11591 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
11592 {
11593 return SHN_COMMON;
11594 }
11595
11596 asection *
_bfd_elf_common_section(asection * sec ATTRIBUTE_UNUSED)11597 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
11598 {
11599 return bfd_com_section_ptr;
11600 }
11601