* elflink.h (elf_link_add_object_symbols): Correct conditions
[deliverable/binutils-gdb.git] / bfd / elflink.h
1 /* ELF linker support.
2 Copyright 1995 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20 /* ELF linker code. */
21
22 static boolean elf_link_add_object_symbols
23 PARAMS ((bfd *, struct bfd_link_info *));
24 static boolean elf_link_add_archive_symbols
25 PARAMS ((bfd *, struct bfd_link_info *));
26 static Elf_Internal_Rela *elf_link_read_relocs
27 PARAMS ((bfd *, asection *, PTR, Elf_Internal_Rela *, boolean));
28 static boolean elf_export_symbol
29 PARAMS ((struct elf_link_hash_entry *, PTR));
30 static boolean elf_adjust_dynamic_symbol
31 PARAMS ((struct elf_link_hash_entry *, PTR));
32
33 /* This struct is used to pass information to routines called via
34 elf_link_hash_traverse which must return failure. */
35
36 struct elf_info_failed
37 {
38 boolean failed;
39 struct bfd_link_info *info;
40 };
41
42 /* Given an ELF BFD, add symbols to the global hash table as
43 appropriate. */
44
45 boolean
46 elf_bfd_link_add_symbols (abfd, info)
47 bfd *abfd;
48 struct bfd_link_info *info;
49 {
50 switch (bfd_get_format (abfd))
51 {
52 case bfd_object:
53 return elf_link_add_object_symbols (abfd, info);
54 case bfd_archive:
55 return elf_link_add_archive_symbols (abfd, info);
56 default:
57 bfd_set_error (bfd_error_wrong_format);
58 return false;
59 }
60 }
61
62 /* Add symbols from an ELF archive file to the linker hash table. We
63 don't use _bfd_generic_link_add_archive_symbols because of a
64 problem which arises on UnixWare. The UnixWare libc.so is an
65 archive which includes an entry libc.so.1 which defines a bunch of
66 symbols. The libc.so archive also includes a number of other
67 object files, which also define symbols, some of which are the same
68 as those defined in libc.so.1. Correct linking requires that we
69 consider each object file in turn, and include it if it defines any
70 symbols we need. _bfd_generic_link_add_archive_symbols does not do
71 this; it looks through the list of undefined symbols, and includes
72 any object file which defines them. When this algorithm is used on
73 UnixWare, it winds up pulling in libc.so.1 early and defining a
74 bunch of symbols. This means that some of the other objects in the
75 archive are not included in the link, which is incorrect since they
76 precede libc.so.1 in the archive.
77
78 Fortunately, ELF archive handling is simpler than that done by
79 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
80 oddities. In ELF, if we find a symbol in the archive map, and the
81 symbol is currently undefined, we know that we must pull in that
82 object file.
83
84 Unfortunately, we do have to make multiple passes over the symbol
85 table until nothing further is resolved. */
86
87 static boolean
88 elf_link_add_archive_symbols (abfd, info)
89 bfd *abfd;
90 struct bfd_link_info *info;
91 {
92 symindex c;
93 boolean *defined = NULL;
94 boolean *included = NULL;
95 carsym *symdefs;
96 boolean loop;
97
98 if (! bfd_has_map (abfd))
99 {
100 /* An empty archive is a special case. */
101 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
102 return true;
103 bfd_set_error (bfd_error_no_armap);
104 return false;
105 }
106
107 /* Keep track of all symbols we know to be already defined, and all
108 files we know to be already included. This is to speed up the
109 second and subsequent passes. */
110 c = bfd_ardata (abfd)->symdef_count;
111 if (c == 0)
112 return true;
113 defined = (boolean *) malloc (c * sizeof (boolean));
114 included = (boolean *) malloc (c * sizeof (boolean));
115 if (defined == (boolean *) NULL || included == (boolean *) NULL)
116 {
117 bfd_set_error (bfd_error_no_memory);
118 goto error_return;
119 }
120 memset (defined, 0, c * sizeof (boolean));
121 memset (included, 0, c * sizeof (boolean));
122
123 symdefs = bfd_ardata (abfd)->symdefs;
124
125 do
126 {
127 file_ptr last;
128 symindex i;
129 carsym *symdef;
130 carsym *symdefend;
131
132 loop = false;
133 last = -1;
134
135 symdef = symdefs;
136 symdefend = symdef + c;
137 for (i = 0; symdef < symdefend; symdef++, i++)
138 {
139 struct elf_link_hash_entry *h;
140 bfd *element;
141 struct bfd_link_hash_entry *undefs_tail;
142 symindex mark;
143
144 if (defined[i] || included[i])
145 continue;
146 if (symdef->file_offset == last)
147 {
148 included[i] = true;
149 continue;
150 }
151
152 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
153 false, false, false);
154 if (h == (struct elf_link_hash_entry *) NULL)
155 continue;
156 if (h->root.type != bfd_link_hash_undefined)
157 {
158 if (h->root.type != bfd_link_hash_undefweak)
159 defined[i] = true;
160 continue;
161 }
162
163 /* We need to include this archive member. */
164
165 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
166 if (element == (bfd *) NULL)
167 goto error_return;
168
169 if (! bfd_check_format (element, bfd_object))
170 goto error_return;
171
172 /* Doublecheck that we have not included this object
173 already--it should be impossible, but there may be
174 something wrong with the archive. */
175 if (element->archive_pass != 0)
176 {
177 bfd_set_error (bfd_error_bad_value);
178 goto error_return;
179 }
180 element->archive_pass = 1;
181
182 undefs_tail = info->hash->undefs_tail;
183
184 if (! (*info->callbacks->add_archive_element) (info, element,
185 symdef->name))
186 goto error_return;
187 if (! elf_link_add_object_symbols (element, info))
188 goto error_return;
189
190 /* If there are any new undefined symbols, we need to make
191 another pass through the archive in order to see whether
192 they can be defined. FIXME: This isn't perfect, because
193 common symbols wind up on undefs_tail and because an
194 undefined symbol which is defined later on in this pass
195 does not require another pass. This isn't a bug, but it
196 does make the code less efficient than it could be. */
197 if (undefs_tail != info->hash->undefs_tail)
198 loop = true;
199
200 /* Look backward to mark all symbols from this object file
201 which we have already seen in this pass. */
202 mark = i;
203 do
204 {
205 included[mark] = true;
206 if (mark == 0)
207 break;
208 --mark;
209 }
210 while (symdefs[mark].file_offset == symdef->file_offset);
211
212 /* We mark subsequent symbols from this object file as we go
213 on through the loop. */
214 last = symdef->file_offset;
215 }
216 }
217 while (loop);
218
219 free (defined);
220 free (included);
221
222 return true;
223
224 error_return:
225 if (defined != (boolean *) NULL)
226 free (defined);
227 if (included != (boolean *) NULL)
228 free (included);
229 return false;
230 }
231
232 /* Add symbols from an ELF object file to the linker hash table. */
233
234 static boolean
235 elf_link_add_object_symbols (abfd, info)
236 bfd *abfd;
237 struct bfd_link_info *info;
238 {
239 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
240 const Elf_Internal_Sym *,
241 const char **, flagword *,
242 asection **, bfd_vma *));
243 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
244 asection *, const Elf_Internal_Rela *));
245 boolean collect;
246 Elf_Internal_Shdr *hdr;
247 size_t symcount;
248 size_t extsymcount;
249 size_t extsymoff;
250 Elf_External_Sym *buf = NULL;
251 struct elf_link_hash_entry **sym_hash;
252 boolean dynamic;
253 Elf_External_Dyn *dynbuf = NULL;
254 struct elf_link_hash_entry *weaks;
255 Elf_External_Sym *esym;
256 Elf_External_Sym *esymend;
257
258 add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook;
259 collect = get_elf_backend_data (abfd)->collect;
260
261 /* As a GNU extension, any input sections which are named
262 .gnu.warning.SYMBOL are treated as warning symbols for the given
263 symbol. This differs from .gnu.warning sections, which generate
264 warnings when they are included in an output file. */
265 if (! info->shared)
266 {
267 asection *s;
268
269 for (s = abfd->sections; s != NULL; s = s->next)
270 {
271 const char *name;
272
273 name = bfd_get_section_name (abfd, s);
274 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
275 {
276 char *msg;
277 bfd_size_type sz;
278
279 sz = bfd_section_size (abfd, s);
280 msg = (char *) bfd_alloc (abfd, sz);
281 if (msg == NULL)
282 {
283 bfd_set_error (bfd_error_no_memory);
284 goto error_return;
285 }
286
287 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
288 goto error_return;
289
290 if (! (_bfd_generic_link_add_one_symbol
291 (info, abfd,
292 name + sizeof ".gnu.warning." - 1,
293 BSF_WARNING, s, (bfd_vma) 0, msg, false, collect,
294 (struct bfd_link_hash_entry **) NULL)))
295 goto error_return;
296
297 if (! info->relocateable)
298 {
299 /* Clobber the section size so that the warning does
300 not get copied into the output file. */
301 s->_raw_size = 0;
302 }
303 }
304 }
305 }
306
307 /* A stripped shared library might only have a dynamic symbol table,
308 not a regular symbol table. In that case we can still go ahead
309 and link using the dynamic symbol table. */
310 if (elf_onesymtab (abfd) == 0
311 && elf_dynsymtab (abfd) != 0)
312 {
313 elf_onesymtab (abfd) = elf_dynsymtab (abfd);
314 elf_tdata (abfd)->symtab_hdr = elf_tdata (abfd)->dynsymtab_hdr;
315 }
316
317 hdr = &elf_tdata (abfd)->symtab_hdr;
318 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
319
320 /* The sh_info field of the symtab header tells us where the
321 external symbols start. We don't care about the local symbols at
322 this point. */
323 if (elf_bad_symtab (abfd))
324 {
325 extsymcount = symcount;
326 extsymoff = 0;
327 }
328 else
329 {
330 extsymcount = symcount - hdr->sh_info;
331 extsymoff = hdr->sh_info;
332 }
333
334 buf = (Elf_External_Sym *) malloc (extsymcount * sizeof (Elf_External_Sym));
335 if (buf == NULL && extsymcount != 0)
336 {
337 bfd_set_error (bfd_error_no_memory);
338 goto error_return;
339 }
340
341 /* We store a pointer to the hash table entry for each external
342 symbol. */
343 sym_hash = ((struct elf_link_hash_entry **)
344 bfd_alloc (abfd,
345 extsymcount * sizeof (struct elf_link_hash_entry *)));
346 if (sym_hash == NULL)
347 {
348 bfd_set_error (bfd_error_no_memory);
349 goto error_return;
350 }
351 elf_sym_hashes (abfd) = sym_hash;
352
353 if (elf_elfheader (abfd)->e_type != ET_DYN)
354 {
355 dynamic = false;
356
357 /* If we are creating a shared library, create all the dynamic
358 sections immediately. We need to attach them to something,
359 so we attach them to this BFD, provided it is the right
360 format. FIXME: If there are no input BFD's of the same
361 format as the output, we can't make a shared library. */
362 if (info->shared
363 && ! elf_hash_table (info)->dynamic_sections_created
364 && abfd->xvec == info->hash->creator)
365 {
366 if (! elf_link_create_dynamic_sections (abfd, info))
367 goto error_return;
368 }
369 }
370 else
371 {
372 asection *s;
373 boolean add_needed;
374 const char *name;
375 bfd_size_type oldsize;
376 bfd_size_type strindex;
377
378 dynamic = true;
379
380 /* You can't use -r against a dynamic object. Also, there's no
381 hope of using a dynamic object which does not exactly match
382 the format of the output file. */
383 if (info->relocateable
384 || info->hash->creator != abfd->xvec)
385 {
386 bfd_set_error (bfd_error_invalid_operation);
387 goto error_return;
388 }
389
390 /* Find the name to use in a DT_NEEDED entry that refers to this
391 object. If the object has a DT_SONAME entry, we use it.
392 Otherwise, if the generic linker stuck something in
393 elf_dt_needed_name, we use that. Otherwise, we just use the
394 file name. If the generic linker put a null string into
395 elf_dt_needed_name, we don't make a DT_NEEDED entry at all,
396 even if there is a DT_SONAME entry. */
397 add_needed = true;
398 name = bfd_get_filename (abfd);
399 if (elf_dt_needed_name (abfd) != NULL)
400 {
401 name = elf_dt_needed_name (abfd);
402 if (*name == '\0')
403 add_needed = false;
404 }
405 s = bfd_get_section_by_name (abfd, ".dynamic");
406 if (s != NULL)
407 {
408 Elf_External_Dyn *extdyn;
409 Elf_External_Dyn *extdynend;
410 int elfsec;
411 unsigned long link;
412
413 dynbuf = (Elf_External_Dyn *) malloc ((size_t) s->_raw_size);
414 if (dynbuf == NULL)
415 {
416 bfd_set_error (bfd_error_no_memory);
417 goto error_return;
418 }
419
420 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
421 (file_ptr) 0, s->_raw_size))
422 goto error_return;
423
424 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
425 if (elfsec == -1)
426 goto error_return;
427 link = elf_elfsections (abfd)[elfsec]->sh_link;
428
429 extdyn = dynbuf;
430 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
431 for (; extdyn < extdynend; extdyn++)
432 {
433 Elf_Internal_Dyn dyn;
434
435 elf_swap_dyn_in (abfd, extdyn, &dyn);
436 if (add_needed && dyn.d_tag == DT_SONAME)
437 {
438 name = bfd_elf_string_from_elf_section (abfd, link,
439 dyn.d_un.d_val);
440 if (name == NULL)
441 goto error_return;
442 }
443 if (dyn.d_tag == DT_NEEDED)
444 {
445 struct bfd_elf_link_needed_list *n, **pn;
446 char *fnm, *anm;
447
448 n = (struct bfd_elf_link_needed_list *)
449 bfd_alloc (abfd,
450 sizeof (struct bfd_elf_link_needed_list));
451 fnm = bfd_elf_string_from_elf_section (abfd, link,
452 dyn.d_un.d_val);
453 if (n == NULL || fnm == NULL)
454 goto error_return;
455 anm = bfd_alloc (abfd, strlen (fnm) + 1);
456 if (anm == NULL)
457 goto error_return;
458 strcpy (anm, fnm);
459 n->name = anm;
460 n->by = abfd;
461 n->next = NULL;
462 for (pn = &elf_hash_table (info)->needed;
463 *pn != NULL;
464 pn = &(*pn)->next)
465 ;
466 *pn = n;
467 }
468 }
469
470 free (dynbuf);
471 dynbuf = NULL;
472 }
473
474 /* We do not want to include any of the sections in a dynamic
475 object in the output file. We hack by simply clobbering the
476 list of sections in the BFD. This could be handled more
477 cleanly by, say, a new section flag; the existing
478 SEC_NEVER_LOAD flag is not the one we want, because that one
479 still implies that the section takes up space in the output
480 file. */
481 abfd->sections = NULL;
482
483 /* If this is the first dynamic object found in the link, create
484 the special sections required for dynamic linking. */
485 if (! elf_hash_table (info)->dynamic_sections_created)
486 {
487 if (! elf_link_create_dynamic_sections (abfd, info))
488 goto error_return;
489 }
490
491 if (add_needed)
492 {
493 /* Add a DT_NEEDED entry for this dynamic object. */
494 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
495 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
496 true, false);
497 if (strindex == (bfd_size_type) -1)
498 goto error_return;
499
500 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
501 {
502 asection *sdyn;
503 Elf_External_Dyn *dyncon, *dynconend;
504
505 /* The hash table size did not change, which means that
506 the dynamic object name was already entered. If we
507 have already included this dynamic object in the
508 link, just ignore it. There is no reason to include
509 a particular dynamic object more than once. */
510 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
511 ".dynamic");
512 BFD_ASSERT (sdyn != NULL);
513
514 dyncon = (Elf_External_Dyn *) sdyn->contents;
515 dynconend = (Elf_External_Dyn *) (sdyn->contents +
516 sdyn->_raw_size);
517 for (; dyncon < dynconend; dyncon++)
518 {
519 Elf_Internal_Dyn dyn;
520
521 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
522 &dyn);
523 if (dyn.d_tag == DT_NEEDED
524 && dyn.d_un.d_val == strindex)
525 {
526 if (buf != NULL)
527 free (buf);
528 return true;
529 }
530 }
531 }
532
533 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
534 goto error_return;
535 }
536 }
537
538 if (bfd_seek (abfd,
539 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
540 SEEK_SET) != 0
541 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
542 != extsymcount * sizeof (Elf_External_Sym)))
543 goto error_return;
544
545 weaks = NULL;
546
547 esymend = buf + extsymcount;
548 for (esym = buf; esym < esymend; esym++, sym_hash++)
549 {
550 Elf_Internal_Sym sym;
551 int bind;
552 bfd_vma value;
553 asection *sec;
554 flagword flags;
555 const char *name;
556 struct elf_link_hash_entry *h;
557 boolean definition;
558 boolean size_change_ok, type_change_ok;
559 boolean new_weakdef;
560
561 elf_swap_symbol_in (abfd, esym, &sym);
562
563 flags = BSF_NO_FLAGS;
564 sec = NULL;
565 value = sym.st_value;
566 *sym_hash = NULL;
567
568 bind = ELF_ST_BIND (sym.st_info);
569 if (bind == STB_LOCAL)
570 {
571 /* This should be impossible, since ELF requires that all
572 global symbols follow all local symbols, and that sh_info
573 point to the first global symbol. Unfortunatealy, Irix 5
574 screws this up. */
575 continue;
576 }
577 else if (bind == STB_GLOBAL)
578 {
579 if (sym.st_shndx != SHN_UNDEF
580 && sym.st_shndx != SHN_COMMON)
581 flags = BSF_GLOBAL;
582 else
583 flags = 0;
584 }
585 else if (bind == STB_WEAK)
586 flags = BSF_WEAK;
587 else
588 {
589 /* Leave it up to the processor backend. */
590 }
591
592 if (sym.st_shndx == SHN_UNDEF)
593 sec = bfd_und_section_ptr;
594 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
595 {
596 sec = section_from_elf_index (abfd, sym.st_shndx);
597 if (sec != NULL)
598 value -= sec->vma;
599 else
600 sec = bfd_abs_section_ptr;
601 }
602 else if (sym.st_shndx == SHN_ABS)
603 sec = bfd_abs_section_ptr;
604 else if (sym.st_shndx == SHN_COMMON)
605 {
606 sec = bfd_com_section_ptr;
607 /* What ELF calls the size we call the value. What ELF
608 calls the value we call the alignment. */
609 value = sym.st_size;
610 }
611 else
612 {
613 /* Leave it up to the processor backend. */
614 }
615
616 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
617 if (name == (const char *) NULL)
618 goto error_return;
619
620 if (add_symbol_hook)
621 {
622 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
623 &value))
624 goto error_return;
625
626 /* The hook function sets the name to NULL if this symbol
627 should be skipped for some reason. */
628 if (name == (const char *) NULL)
629 continue;
630 }
631
632 /* Sanity check that all possibilities were handled. */
633 if (sec == (asection *) NULL)
634 {
635 bfd_set_error (bfd_error_bad_value);
636 goto error_return;
637 }
638
639 if (bfd_is_und_section (sec)
640 || bfd_is_com_section (sec))
641 definition = false;
642 else
643 definition = true;
644
645 size_change_ok = false;
646 type_change_ok = false;
647 if (info->hash->creator->flavour == bfd_target_elf_flavour)
648 {
649 /* We need to look up the symbol now in order to get some of
650 the dynamic object handling right. We pass the hash
651 table entry in to _bfd_generic_link_add_one_symbol so
652 that it does not have to look it up again. */
653 h = elf_link_hash_lookup (elf_hash_table (info), name,
654 true, false, false);
655 if (h == NULL)
656 goto error_return;
657 *sym_hash = h;
658
659 while (h->root.type == bfd_link_hash_indirect
660 || h->root.type == bfd_link_hash_warning)
661 h = (struct elf_link_hash_entry *) h->root.u.i.link;
662
663 /* It's OK to change the type if it used to be a weak
664 definition. */
665 type_change_ok = (h->root.type == bfd_link_hash_defweak
666 || h->root.type == bfd_link_hash_undefweak);
667
668 /* It's OK to change the size if it used to be a weak
669 definition, or if it used to be undefined, or if we will
670 be overriding an old definition.
671 */
672 size_change_ok = (type_change_ok
673 || h->root.type == bfd_link_hash_undefined);
674
675 /* If we are looking at a dynamic object, and this is a
676 definition, we need to see if it has already been defined
677 by some other object. If it has, we want to use the
678 existing definition, and we do not want to report a
679 multiple symbol definition error; we do this by
680 clobbering sec to be bfd_und_section_ptr. */
681 if (dynamic && definition)
682 {
683 if (h->root.type == bfd_link_hash_defined
684 || h->root.type == bfd_link_hash_defweak
685 || (h->root.type == bfd_link_hash_common
686 && bind == STB_WEAK))
687 {
688 sec = bfd_und_section_ptr;
689 definition = false;
690 size_change_ok = true;
691 }
692 }
693
694 /* Similarly, if we are not looking at a dynamic object, and
695 we have a definition, we want to override any definition
696 we may have from a dynamic object. Symbols from regular
697 files always take precedence over symbols from dynamic
698 objects, even if they are defined after the dynamic
699 object in the link. */
700 if (! dynamic
701 && definition
702 && (h->root.type == bfd_link_hash_defined
703 || h->root.type == bfd_link_hash_defweak)
704 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
705 && (bfd_get_flavour (h->root.u.def.section->owner)
706 == bfd_target_elf_flavour)
707 && (elf_elfheader (h->root.u.def.section->owner)->e_type
708 == ET_DYN))
709 {
710 /* Change the hash table entry to undefined, and let
711 _bfd_generic_link_add_one_symbol do the right thing
712 with the new definition. */
713 h->root.type = bfd_link_hash_undefined;
714 h->root.u.undef.abfd = h->root.u.def.section->owner;
715 size_change_ok = true;
716 }
717 }
718
719 if (! (_bfd_generic_link_add_one_symbol
720 (info, abfd, name, flags, sec, value, (const char *) NULL,
721 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
722 goto error_return;
723
724 h = *sym_hash;
725 while (h->root.type == bfd_link_hash_indirect
726 || h->root.type == bfd_link_hash_warning)
727 h = (struct elf_link_hash_entry *) h->root.u.i.link;
728 *sym_hash = h;
729
730 new_weakdef = false;
731 if (dynamic
732 && definition
733 && (flags & BSF_WEAK) != 0
734 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
735 && info->hash->creator->flavour == bfd_target_elf_flavour
736 && h->weakdef == NULL)
737 {
738 /* Keep a list of all weak defined non function symbols from
739 a dynamic object, using the weakdef field. Later in this
740 function we will set the weakdef field to the correct
741 value. We only put non-function symbols from dynamic
742 objects on this list, because that happens to be the only
743 time we need to know the normal symbol corresponding to a
744 weak symbol, and the information is time consuming to
745 figure out. If the weakdef field is not already NULL,
746 then this symbol was already defined by some previous
747 dynamic object, and we will be using that previous
748 definition anyhow. */
749
750 h->weakdef = weaks;
751 weaks = h;
752 new_weakdef = true;
753 }
754
755 /* Get the alignment of a common symbol. */
756 if (sym.st_shndx == SHN_COMMON
757 && h->root.type == bfd_link_hash_common)
758 h->root.u.c.p->alignment_power = bfd_log2 (sym.st_value);
759
760 if (info->hash->creator->flavour == bfd_target_elf_flavour)
761 {
762 int old_flags;
763 boolean dynsym;
764 int new_flag;
765
766 /* Remember the symbol size and type. */
767 if (sym.st_size != 0
768 && (definition || h->size == 0))
769 {
770 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
771 (*_bfd_error_handler)
772 ("Warning: size of symbol `%s' changed from %lu to %lu in %s",
773 name, (unsigned long) h->size, (unsigned long) sym.st_size,
774 bfd_get_filename (abfd));
775
776 h->size = sym.st_size;
777 }
778 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
779 && (definition || h->type == STT_NOTYPE))
780 {
781 if (h->type != STT_NOTYPE
782 && h->type != ELF_ST_TYPE (sym.st_info)
783 && ! type_change_ok)
784 (*_bfd_error_handler)
785 ("Warning: type of symbol `%s' changed from %d to %d in %s",
786 name, h->type, ELF_ST_TYPE (sym.st_info),
787 bfd_get_filename (abfd));
788
789 h->type = ELF_ST_TYPE (sym.st_info);
790 }
791
792 /* Set a flag in the hash table entry indicating the type of
793 reference or definition we just found. Keep a count of
794 the number of dynamic symbols we find. A dynamic symbol
795 is one which is referenced or defined by both a regular
796 object and a shared object, or one which is referenced or
797 defined by more than one shared object. */
798 old_flags = h->elf_link_hash_flags;
799 dynsym = false;
800 if (! dynamic)
801 {
802 if (! definition)
803 new_flag = ELF_LINK_HASH_REF_REGULAR;
804 else
805 new_flag = ELF_LINK_HASH_DEF_REGULAR;
806 if (info->shared
807 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
808 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
809 dynsym = true;
810 }
811 else
812 {
813 if (! definition)
814 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
815 else
816 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
817 if ((old_flags & new_flag) != 0
818 || (old_flags & (ELF_LINK_HASH_DEF_REGULAR
819 | ELF_LINK_HASH_REF_REGULAR)) != 0
820 || (h->weakdef != NULL
821 && (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
822 | ELF_LINK_HASH_REF_DYNAMIC)) != 0))
823 dynsym = true;
824 }
825
826 h->elf_link_hash_flags |= new_flag;
827 if (dynsym && h->dynindx == -1)
828 {
829 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
830 goto error_return;
831 if (h->weakdef != NULL
832 && ! new_weakdef
833 && h->weakdef->dynindx == -1)
834 {
835 if (! _bfd_elf_link_record_dynamic_symbol (info,
836 h->weakdef))
837 goto error_return;
838 }
839 }
840 }
841 }
842
843 /* Now set the weakdefs field correctly for all the weak defined
844 symbols we found. The only way to do this is to search all the
845 symbols. Since we only need the information for non functions in
846 dynamic objects, that's the only time we actually put anything on
847 the list WEAKS. We need this information so that if a regular
848 object refers to a symbol defined weakly in a dynamic object, the
849 real symbol in the dynamic object is also put in the dynamic
850 symbols; we also must arrange for both symbols to point to the
851 same memory location. We could handle the general case of symbol
852 aliasing, but a general symbol alias can only be generated in
853 assembler code, handling it correctly would be very time
854 consuming, and other ELF linkers don't handle general aliasing
855 either. */
856 while (weaks != NULL)
857 {
858 struct elf_link_hash_entry *hlook;
859 asection *slook;
860 bfd_vma vlook;
861 struct elf_link_hash_entry **hpp;
862 struct elf_link_hash_entry **hppend;
863
864 hlook = weaks;
865 weaks = hlook->weakdef;
866 hlook->weakdef = NULL;
867
868 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
869 || hlook->root.type == bfd_link_hash_defweak
870 || hlook->root.type == bfd_link_hash_common
871 || hlook->root.type == bfd_link_hash_indirect);
872 slook = hlook->root.u.def.section;
873 vlook = hlook->root.u.def.value;
874
875 hpp = elf_sym_hashes (abfd);
876 hppend = hpp + extsymcount;
877 for (; hpp < hppend; hpp++)
878 {
879 struct elf_link_hash_entry *h;
880
881 h = *hpp;
882 if (h != NULL && h != hlook
883 && (h->root.type == bfd_link_hash_defined
884 || h->root.type == bfd_link_hash_defweak)
885 && h->root.u.def.section == slook
886 && h->root.u.def.value == vlook)
887 {
888 hlook->weakdef = h;
889
890 /* If the weak definition is in the list of dynamic
891 symbols, make sure the real definition is put there
892 as well. */
893 if (hlook->dynindx != -1
894 && h->dynindx == -1)
895 {
896 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
897 goto error_return;
898 }
899
900 break;
901 }
902 }
903 }
904
905 if (buf != NULL)
906 {
907 free (buf);
908 buf = NULL;
909 }
910
911 /* If this object is the same format as the output object, and it is
912 not a shared library, then let the backend look through the
913 relocs.
914
915 This is required to build global offset table entries and to
916 arrange for dynamic relocs. It is not required for the
917 particular common case of linking non PIC code, even when linking
918 against shared libraries, but unfortunately there is no way of
919 knowing whether an object file has been compiled PIC or not.
920 Looking through the relocs is not particularly time consuming.
921 The problem is that we must either (1) keep the relocs in memory,
922 which causes the linker to require additional runtime memory or
923 (2) read the relocs twice from the input file, which wastes time.
924 This would be a good case for using mmap.
925
926 I have no idea how to handle linking PIC code into a file of a
927 different format. It probably can't be done. */
928 check_relocs = get_elf_backend_data (abfd)->check_relocs;
929 if (! dynamic
930 && abfd->xvec == info->hash->creator
931 && check_relocs != NULL)
932 {
933 asection *o;
934
935 for (o = abfd->sections; o != NULL; o = o->next)
936 {
937 Elf_Internal_Rela *internal_relocs;
938 boolean ok;
939
940 if ((o->flags & SEC_RELOC) == 0
941 || o->reloc_count == 0)
942 continue;
943
944 /* I believe we can ignore the relocs for any section which
945 does not form part of the final process image, such as a
946 debugging section. */
947 if ((o->flags & SEC_ALLOC) == 0)
948 continue;
949
950 internal_relocs = elf_link_read_relocs (abfd, o, (PTR) NULL,
951 (Elf_Internal_Rela *) NULL,
952 info->keep_memory);
953 if (internal_relocs == NULL)
954 goto error_return;
955
956 ok = (*check_relocs) (abfd, info, o, internal_relocs);
957
958 if (! info->keep_memory)
959 free (internal_relocs);
960
961 if (! ok)
962 goto error_return;
963 }
964 }
965
966 return true;
967
968 error_return:
969 if (buf != NULL)
970 free (buf);
971 if (dynbuf != NULL)
972 free (dynbuf);
973 return false;
974 }
975
976 /* Create some sections which will be filled in with dynamic linking
977 information. ABFD is an input file which requires dynamic sections
978 to be created. The dynamic sections take up virtual memory space
979 when the final executable is run, so we need to create them before
980 addresses are assigned to the output sections. We work out the
981 actual contents and size of these sections later. */
982
983 boolean
984 elf_link_create_dynamic_sections (abfd, info)
985 bfd *abfd;
986 struct bfd_link_info *info;
987 {
988 flagword flags;
989 register asection *s;
990 struct elf_link_hash_entry *h;
991 struct elf_backend_data *bed;
992
993 if (elf_hash_table (info)->dynamic_sections_created)
994 return true;
995
996 /* Make sure that all dynamic sections use the same input BFD. */
997 if (elf_hash_table (info)->dynobj == NULL)
998 elf_hash_table (info)->dynobj = abfd;
999 else
1000 abfd = elf_hash_table (info)->dynobj;
1001
1002 /* Note that we set the SEC_IN_MEMORY flag for all of these
1003 sections. */
1004 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
1005
1006 /* A dynamically linked executable has a .interp section, but a
1007 shared library does not. */
1008 if (! info->shared)
1009 {
1010 s = bfd_make_section (abfd, ".interp");
1011 if (s == NULL
1012 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1013 return false;
1014 }
1015
1016 s = bfd_make_section (abfd, ".dynsym");
1017 if (s == NULL
1018 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1019 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1020 return false;
1021
1022 s = bfd_make_section (abfd, ".dynstr");
1023 if (s == NULL
1024 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1025 return false;
1026
1027 /* Create a strtab to hold the dynamic symbol names. */
1028 if (elf_hash_table (info)->dynstr == NULL)
1029 {
1030 elf_hash_table (info)->dynstr = elf_stringtab_init ();
1031 if (elf_hash_table (info)->dynstr == NULL)
1032 return false;
1033 }
1034
1035 s = bfd_make_section (abfd, ".dynamic");
1036 if (s == NULL
1037 || ! bfd_set_section_flags (abfd, s, flags)
1038 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1039 return false;
1040
1041 /* The special symbol _DYNAMIC is always set to the start of the
1042 .dynamic section. This call occurs before we have processed the
1043 symbols for any dynamic object, so we don't have to worry about
1044 overriding a dynamic definition. We could set _DYNAMIC in a
1045 linker script, but we only want to define it if we are, in fact,
1046 creating a .dynamic section. We don't want to define it if there
1047 is no .dynamic section, since on some ELF platforms the start up
1048 code examines it to decide how to initialize the process. */
1049 h = NULL;
1050 if (! (_bfd_generic_link_add_one_symbol
1051 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
1052 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
1053 (struct bfd_link_hash_entry **) &h)))
1054 return false;
1055 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
1056 h->type = STT_OBJECT;
1057
1058 if (info->shared
1059 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
1060 return false;
1061
1062 s = bfd_make_section (abfd, ".hash");
1063 if (s == NULL
1064 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1065 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1066 return false;
1067
1068 /* Let the backend create the rest of the sections. This lets the
1069 backend set the right flags. The backend will normally create
1070 the .got and .plt sections. */
1071 bed = get_elf_backend_data (abfd);
1072 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
1073 return false;
1074
1075 elf_hash_table (info)->dynamic_sections_created = true;
1076
1077 return true;
1078 }
1079
1080 /* Add an entry to the .dynamic table. */
1081
1082 boolean
1083 elf_add_dynamic_entry (info, tag, val)
1084 struct bfd_link_info *info;
1085 bfd_vma tag;
1086 bfd_vma val;
1087 {
1088 Elf_Internal_Dyn dyn;
1089 bfd *dynobj;
1090 asection *s;
1091 size_t newsize;
1092 bfd_byte *newcontents;
1093
1094 dynobj = elf_hash_table (info)->dynobj;
1095
1096 s = bfd_get_section_by_name (dynobj, ".dynamic");
1097 BFD_ASSERT (s != NULL);
1098
1099 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
1100 if (s->contents == NULL)
1101 newcontents = (bfd_byte *) malloc (newsize);
1102 else
1103 newcontents = (bfd_byte *) realloc (s->contents, newsize);
1104 if (newcontents == NULL)
1105 {
1106 bfd_set_error (bfd_error_no_memory);
1107 return false;
1108 }
1109
1110 dyn.d_tag = tag;
1111 dyn.d_un.d_val = val;
1112 elf_swap_dyn_out (dynobj, &dyn,
1113 (Elf_External_Dyn *) (newcontents + s->_raw_size));
1114
1115 s->_raw_size = newsize;
1116 s->contents = newcontents;
1117
1118 return true;
1119 }
1120
1121 /* Read and swap the relocs for a section. They may have been cached.
1122 If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are not NULL,
1123 they are used as buffers to read into. They are known to be large
1124 enough. If the INTERNAL_RELOCS relocs argument is NULL, the return
1125 value is allocated using either malloc or bfd_alloc, according to
1126 the KEEP_MEMORY argument. */
1127
1128 static Elf_Internal_Rela *
1129 elf_link_read_relocs (abfd, o, external_relocs, internal_relocs, keep_memory)
1130 bfd *abfd;
1131 asection *o;
1132 PTR external_relocs;
1133 Elf_Internal_Rela *internal_relocs;
1134 boolean keep_memory;
1135 {
1136 Elf_Internal_Shdr *rel_hdr;
1137 PTR alloc1 = NULL;
1138 Elf_Internal_Rela *alloc2 = NULL;
1139
1140 if (elf_section_data (o)->relocs != NULL)
1141 return elf_section_data (o)->relocs;
1142
1143 if (o->reloc_count == 0)
1144 return NULL;
1145
1146 rel_hdr = &elf_section_data (o)->rel_hdr;
1147
1148 if (internal_relocs == NULL)
1149 {
1150 size_t size;
1151
1152 size = o->reloc_count * sizeof (Elf_Internal_Rela);
1153 if (keep_memory)
1154 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
1155 else
1156 internal_relocs = alloc2 = (Elf_Internal_Rela *) malloc (size);
1157 if (internal_relocs == NULL)
1158 {
1159 bfd_set_error (bfd_error_no_memory);
1160 goto error_return;
1161 }
1162 }
1163
1164 if (external_relocs == NULL)
1165 {
1166 alloc1 = (PTR) malloc ((size_t) rel_hdr->sh_size);
1167 if (alloc1 == NULL)
1168 {
1169 bfd_set_error (bfd_error_no_memory);
1170 goto error_return;
1171 }
1172 external_relocs = alloc1;
1173 }
1174
1175 if ((bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0)
1176 || (bfd_read (external_relocs, 1, rel_hdr->sh_size, abfd)
1177 != rel_hdr->sh_size))
1178 goto error_return;
1179
1180 /* Swap in the relocs. For convenience, we always produce an
1181 Elf_Internal_Rela array; if the relocs are Rel, we set the addend
1182 to 0. */
1183 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
1184 {
1185 Elf_External_Rel *erel;
1186 Elf_External_Rel *erelend;
1187 Elf_Internal_Rela *irela;
1188
1189 erel = (Elf_External_Rel *) external_relocs;
1190 erelend = erel + o->reloc_count;
1191 irela = internal_relocs;
1192 for (; erel < erelend; erel++, irela++)
1193 {
1194 Elf_Internal_Rel irel;
1195
1196 elf_swap_reloc_in (abfd, erel, &irel);
1197 irela->r_offset = irel.r_offset;
1198 irela->r_info = irel.r_info;
1199 irela->r_addend = 0;
1200 }
1201 }
1202 else
1203 {
1204 Elf_External_Rela *erela;
1205 Elf_External_Rela *erelaend;
1206 Elf_Internal_Rela *irela;
1207
1208 BFD_ASSERT (rel_hdr->sh_entsize == sizeof (Elf_External_Rela));
1209
1210 erela = (Elf_External_Rela *) external_relocs;
1211 erelaend = erela + o->reloc_count;
1212 irela = internal_relocs;
1213 for (; erela < erelaend; erela++, irela++)
1214 elf_swap_reloca_in (abfd, erela, irela);
1215 }
1216
1217 /* Cache the results for next time, if we can. */
1218 if (keep_memory)
1219 elf_section_data (o)->relocs = internal_relocs;
1220
1221 if (alloc1 != NULL)
1222 free (alloc1);
1223
1224 /* Don't free alloc2, since if it was allocated we are passing it
1225 back (under the name of internal_relocs). */
1226
1227 return internal_relocs;
1228
1229 error_return:
1230 if (alloc1 != NULL)
1231 free (alloc1);
1232 if (alloc2 != NULL)
1233 free (alloc2);
1234 return NULL;
1235 }
1236
1237 /* Record an assignment to a symbol made by a linker script. We need
1238 this in case some dynamic object refers to this symbol. */
1239
1240 /*ARGSUSED*/
1241 boolean
1242 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
1243 bfd *output_bfd;
1244 struct bfd_link_info *info;
1245 const char *name;
1246 boolean provide;
1247 {
1248 struct elf_link_hash_entry *h;
1249
1250 if (info->hash->creator->flavour != bfd_target_elf_flavour)
1251 return true;
1252
1253 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
1254 if (h == NULL)
1255 return false;
1256
1257 /* If this symbol is being provided by the linker script, and it is
1258 currently defined by a dynamic object, but not by a regular
1259 object, then mark it as undefined so that the generic linker will
1260 force the correct value. */
1261 if (provide
1262 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1263 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1264 h->root.type = bfd_link_hash_undefined;
1265
1266 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
1267 h->type = STT_OBJECT;
1268
1269 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1270 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
1271 || info->shared)
1272 && h->dynindx == -1)
1273 {
1274 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1275 return false;
1276
1277 /* If this is a weak defined symbol, and we know a corresponding
1278 real symbol from the same dynamic object, make sure the real
1279 symbol is also made into a dynamic symbol. */
1280 if (h->weakdef != NULL
1281 && h->weakdef->dynindx == -1)
1282 {
1283 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
1284 return false;
1285 }
1286 }
1287
1288 return true;
1289 }
1290
1291 /* Array used to determine the number of hash table buckets to use
1292 based on the number of symbols there are. If there are fewer than
1293 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
1294 fewer than 37 we use 17 buckets, and so forth. We never use more
1295 than 521 buckets. */
1296
1297 static const size_t elf_buckets[] =
1298 {
1299 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 0
1300 };
1301
1302 /* Set up the sizes and contents of the ELF dynamic sections. This is
1303 called by the ELF linker emulation before_allocation routine. We
1304 must set the sizes of the sections before the linker sets the
1305 addresses of the various sections. */
1306
1307 boolean
1308 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
1309 export_dynamic, info, sinterpptr)
1310 bfd *output_bfd;
1311 const char *soname;
1312 const char *rpath;
1313 boolean export_dynamic;
1314 struct bfd_link_info *info;
1315 asection **sinterpptr;
1316 {
1317 bfd *dynobj;
1318 struct elf_backend_data *bed;
1319
1320 *sinterpptr = NULL;
1321
1322 if (info->hash->creator->flavour != bfd_target_elf_flavour)
1323 return true;
1324
1325 dynobj = elf_hash_table (info)->dynobj;
1326
1327 /* If there were no dynamic objects in the link, there is nothing to
1328 do here. */
1329 if (dynobj == NULL)
1330 return true;
1331
1332 /* If we are supposed to export all symbols into the dynamic symbol
1333 table (this is not the normal case), then do so. */
1334 if (export_dynamic)
1335 {
1336 struct elf_info_failed eif;
1337
1338 eif.failed = false;
1339 eif.info = info;
1340 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
1341 (PTR) &eif);
1342 if (eif.failed)
1343 return false;
1344 }
1345
1346 if (elf_hash_table (info)->dynamic_sections_created)
1347 {
1348 struct elf_info_failed eif;
1349 bfd_size_type strsize;
1350
1351 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
1352 BFD_ASSERT (*sinterpptr != NULL || info->shared);
1353
1354 if (soname != NULL)
1355 {
1356 bfd_size_type indx;
1357
1358 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, soname,
1359 true, true);
1360 if (indx == (bfd_size_type) -1
1361 || ! elf_add_dynamic_entry (info, DT_SONAME, indx))
1362 return false;
1363 }
1364
1365 if (info->symbolic)
1366 {
1367 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
1368 return false;
1369 }
1370
1371 if (rpath != NULL)
1372 {
1373 bfd_size_type indx;
1374
1375 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
1376 true, true);
1377 if (indx == (bfd_size_type) -1
1378 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
1379 return false;
1380 }
1381
1382 /* Find all symbols which were defined in a dynamic object and make
1383 the backend pick a reasonable value for them. */
1384 eif.failed = false;
1385 eif.info = info;
1386 elf_link_hash_traverse (elf_hash_table (info),
1387 elf_adjust_dynamic_symbol,
1388 (PTR) &eif);
1389 if (eif.failed)
1390 return false;
1391
1392 /* Add some entries to the .dynamic section. We fill in some of the
1393 values later, in elf_bfd_final_link, but we must add the entries
1394 now so that we know the final size of the .dynamic section. */
1395 if (elf_link_hash_lookup (elf_hash_table (info), "_init", false,
1396 false, false) != NULL)
1397 {
1398 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
1399 return false;
1400 }
1401 if (elf_link_hash_lookup (elf_hash_table (info), "_fini", false,
1402 false, false) != NULL)
1403 {
1404 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
1405 return false;
1406 }
1407 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1408 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
1409 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
1410 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
1411 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
1412 || ! elf_add_dynamic_entry (info, DT_SYMENT,
1413 sizeof (Elf_External_Sym)))
1414 return false;
1415 }
1416
1417 /* The backend must work out the sizes of all the other dynamic
1418 sections. */
1419 bed = get_elf_backend_data (output_bfd);
1420 if (! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
1421 return false;
1422
1423 if (elf_hash_table (info)->dynamic_sections_created)
1424 {
1425 size_t dynsymcount;
1426 asection *s;
1427 size_t i;
1428 size_t bucketcount = 0;
1429 Elf_Internal_Sym isym;
1430
1431 /* Set the size of the .dynsym and .hash sections. We counted
1432 the number of dynamic symbols in elf_link_add_object_symbols.
1433 We will build the contents of .dynsym and .hash when we build
1434 the final symbol table, because until then we do not know the
1435 correct value to give the symbols. We built the .dynstr
1436 section as we went along in elf_link_add_object_symbols. */
1437 dynsymcount = elf_hash_table (info)->dynsymcount;
1438 s = bfd_get_section_by_name (dynobj, ".dynsym");
1439 BFD_ASSERT (s != NULL);
1440 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
1441 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
1442 if (s->contents == NULL && s->_raw_size != 0)
1443 {
1444 bfd_set_error (bfd_error_no_memory);
1445 return false;
1446 }
1447
1448 /* The first entry in .dynsym is a dummy symbol. */
1449 isym.st_value = 0;
1450 isym.st_size = 0;
1451 isym.st_name = 0;
1452 isym.st_info = 0;
1453 isym.st_other = 0;
1454 isym.st_shndx = 0;
1455 elf_swap_symbol_out (output_bfd, &isym,
1456 (PTR) (Elf_External_Sym *) s->contents);
1457
1458 for (i = 0; elf_buckets[i] != 0; i++)
1459 {
1460 bucketcount = elf_buckets[i];
1461 if (dynsymcount < elf_buckets[i + 1])
1462 break;
1463 }
1464
1465 s = bfd_get_section_by_name (dynobj, ".hash");
1466 BFD_ASSERT (s != NULL);
1467 s->_raw_size = (2 + bucketcount + dynsymcount) * (ARCH_SIZE / 8);
1468 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
1469 if (s->contents == NULL)
1470 {
1471 bfd_set_error (bfd_error_no_memory);
1472 return false;
1473 }
1474 memset (s->contents, 0, (size_t) s->_raw_size);
1475
1476 put_word (output_bfd, bucketcount, s->contents);
1477 put_word (output_bfd, dynsymcount, s->contents + (ARCH_SIZE / 8));
1478
1479 elf_hash_table (info)->bucketcount = bucketcount;
1480
1481 s = bfd_get_section_by_name (dynobj, ".dynstr");
1482 BFD_ASSERT (s != NULL);
1483 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1484
1485 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
1486 return false;
1487 }
1488
1489 return true;
1490 }
1491
1492 /* This routine is used to export all defined symbols into the dynamic
1493 symbol table. It is called via elf_link_hash_traverse. */
1494
1495 static boolean
1496 elf_export_symbol (h, data)
1497 struct elf_link_hash_entry *h;
1498 PTR data;
1499 {
1500 struct elf_info_failed *eif = (struct elf_info_failed *) data;
1501
1502 if (h->dynindx == -1
1503 && (h->elf_link_hash_flags
1504 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
1505 {
1506 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
1507 {
1508 eif->failed = true;
1509 return false;
1510 }
1511 }
1512
1513 return true;
1514 }
1515
1516 /* Make the backend pick a good value for a dynamic symbol. This is
1517 called via elf_link_hash_traverse, and also calls itself
1518 recursively. */
1519
1520 static boolean
1521 elf_adjust_dynamic_symbol (h, data)
1522 struct elf_link_hash_entry *h;
1523 PTR data;
1524 {
1525 struct elf_info_failed *eif = (struct elf_info_failed *) data;
1526 bfd *dynobj;
1527 struct elf_backend_data *bed;
1528
1529 /* If -Bsymbolic was used (which means to bind references to global
1530 symbols to the definition within the shared object), and this
1531 symbol was defined in a regular object, then it actually doesn't
1532 need a PLT entry. */
1533 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
1534 && eif->info->shared
1535 && eif->info->symbolic
1536 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
1537 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
1538
1539 /* If this symbol does not require a PLT entry, and it is not
1540 defined by a dynamic object, or is not referenced by a regular
1541 object, ignore it. We do have to handle a weak defined symbol,
1542 even if no regular object refers to it, if we decided to add it
1543 to the dynamic symbol table. FIXME: Do we normally need to worry
1544 about symbols which are defined by one dynamic object and
1545 referenced by another one? */
1546 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
1547 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1548 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1549 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
1550 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
1551 return true;
1552
1553 /* If we've already adjusted this symbol, don't do it again. This
1554 can happen via a recursive call. */
1555 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
1556 return true;
1557
1558 /* Don't look at this symbol again. Note that we must set this
1559 after checking the above conditions, because we may look at a
1560 symbol once, decide not to do anything, and then get called
1561 recursively later after REF_REGULAR is set below. */
1562 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
1563
1564 /* If this is a weak definition, and we know a real definition, and
1565 the real symbol is not itself defined by a regular object file,
1566 then get a good value for the real definition. We handle the
1567 real symbol first, for the convenience of the backend routine.
1568
1569 Note that there is a confusing case here. If the real definition
1570 is defined by a regular object file, we don't get the real symbol
1571 from the dynamic object, but we do get the weak symbol. If the
1572 processor backend uses a COPY reloc, then if some routine in the
1573 dynamic object changes the real symbol, we will not see that
1574 change in the corresponding weak symbol. This is the way other
1575 ELF linkers work as well, and seems to be a result of the shared
1576 library model.
1577
1578 I will clarify this issue. Most SVR4 shared libraries define the
1579 variable _timezone and define timezone as a weak synonym. The
1580 tzset call changes _timezone. If you write
1581 extern int timezone;
1582 int _timezone = 5;
1583 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
1584 you might expect that, since timezone is a synonym for _timezone,
1585 the same number will print both times. However, if the processor
1586 backend uses a COPY reloc, then actually timezone will be copied
1587 into your process image, and, since you define _timezone
1588 yourself, _timezone will not. Thus timezone and _timezone will
1589 wind up at different memory locations. The tzset call will set
1590 _timezone, leaving timezone unchanged. */
1591
1592 if (h->weakdef != NULL)
1593 {
1594 struct elf_link_hash_entry *weakdef;
1595
1596 BFD_ASSERT (h->root.type == bfd_link_hash_defined
1597 || h->root.type == bfd_link_hash_defweak);
1598 weakdef = h->weakdef;
1599 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
1600 || weakdef->root.type == bfd_link_hash_defweak);
1601 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
1602 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
1603 {
1604 /* This symbol is defined by a regular object file, so we
1605 will not do anything special. Clear weakdef for the
1606 convenience of the processor backend. */
1607 h->weakdef = NULL;
1608 }
1609 else
1610 {
1611 /* There is an implicit reference by a regular object file
1612 via the weak symbol. */
1613 weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
1614 if (! elf_adjust_dynamic_symbol (weakdef, (PTR) eif))
1615 return false;
1616 }
1617 }
1618
1619 dynobj = elf_hash_table (eif->info)->dynobj;
1620 bed = get_elf_backend_data (dynobj);
1621 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
1622 {
1623 eif->failed = true;
1624 return false;
1625 }
1626
1627 return true;
1628 }
1629 \f
1630 /* Final phase of ELF linker. */
1631
1632 /* A structure we use to avoid passing large numbers of arguments. */
1633
1634 struct elf_final_link_info
1635 {
1636 /* General link information. */
1637 struct bfd_link_info *info;
1638 /* Output BFD. */
1639 bfd *output_bfd;
1640 /* Symbol string table. */
1641 struct bfd_strtab_hash *symstrtab;
1642 /* .dynsym section. */
1643 asection *dynsym_sec;
1644 /* .hash section. */
1645 asection *hash_sec;
1646 /* Buffer large enough to hold contents of any section. */
1647 bfd_byte *contents;
1648 /* Buffer large enough to hold external relocs of any section. */
1649 PTR external_relocs;
1650 /* Buffer large enough to hold internal relocs of any section. */
1651 Elf_Internal_Rela *internal_relocs;
1652 /* Buffer large enough to hold external local symbols of any input
1653 BFD. */
1654 Elf_External_Sym *external_syms;
1655 /* Buffer large enough to hold internal local symbols of any input
1656 BFD. */
1657 Elf_Internal_Sym *internal_syms;
1658 /* Array large enough to hold a symbol index for each local symbol
1659 of any input BFD. */
1660 long *indices;
1661 /* Array large enough to hold a section pointer for each local
1662 symbol of any input BFD. */
1663 asection **sections;
1664 /* Buffer to hold swapped out symbols. */
1665 Elf_External_Sym *symbuf;
1666 /* Number of swapped out symbols in buffer. */
1667 size_t symbuf_count;
1668 /* Number of symbols which fit in symbuf. */
1669 size_t symbuf_size;
1670 };
1671
1672 static boolean elf_link_output_sym
1673 PARAMS ((struct elf_final_link_info *, const char *,
1674 Elf_Internal_Sym *, asection *));
1675 static boolean elf_link_flush_output_syms
1676 PARAMS ((struct elf_final_link_info *));
1677 static boolean elf_link_output_extsym
1678 PARAMS ((struct elf_link_hash_entry *, PTR));
1679 static boolean elf_link_input_bfd
1680 PARAMS ((struct elf_final_link_info *, bfd *));
1681 static boolean elf_reloc_link_order
1682 PARAMS ((bfd *, struct bfd_link_info *, asection *,
1683 struct bfd_link_order *));
1684
1685 /* This struct is used to pass information to routines called via
1686 elf_link_hash_traverse which must return failure. */
1687
1688 struct elf_finfo_failed
1689 {
1690 boolean failed;
1691 struct elf_final_link_info *finfo;
1692 };
1693
1694 /* Do the final step of an ELF link. */
1695
1696 boolean
1697 elf_bfd_final_link (abfd, info)
1698 bfd *abfd;
1699 struct bfd_link_info *info;
1700 {
1701 boolean dynamic;
1702 bfd *dynobj;
1703 struct elf_final_link_info finfo;
1704 register asection *o;
1705 register struct bfd_link_order *p;
1706 register bfd *sub;
1707 size_t max_contents_size;
1708 size_t max_external_reloc_size;
1709 size_t max_internal_reloc_count;
1710 size_t max_sym_count;
1711 file_ptr off;
1712 Elf_Internal_Sym elfsym;
1713 unsigned int i;
1714 Elf_Internal_Shdr *symtab_hdr;
1715 Elf_Internal_Shdr *symstrtab_hdr;
1716 struct elf_backend_data *bed = get_elf_backend_data (abfd);
1717 struct elf_finfo_failed eif;
1718
1719 if (info->shared)
1720 abfd->flags |= DYNAMIC;
1721
1722 dynamic = elf_hash_table (info)->dynamic_sections_created;
1723 dynobj = elf_hash_table (info)->dynobj;
1724
1725 finfo.info = info;
1726 finfo.output_bfd = abfd;
1727 finfo.symstrtab = elf_stringtab_init ();
1728 if (finfo.symstrtab == NULL)
1729 return false;
1730 if (! dynamic)
1731 {
1732 finfo.dynsym_sec = NULL;
1733 finfo.hash_sec = NULL;
1734 }
1735 else
1736 {
1737 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
1738 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
1739 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
1740 }
1741 finfo.contents = NULL;
1742 finfo.external_relocs = NULL;
1743 finfo.internal_relocs = NULL;
1744 finfo.external_syms = NULL;
1745 finfo.internal_syms = NULL;
1746 finfo.indices = NULL;
1747 finfo.sections = NULL;
1748 finfo.symbuf = NULL;
1749 finfo.symbuf_count = 0;
1750
1751 /* Count up the number of relocations we will output for each output
1752 section, so that we know the sizes of the reloc sections. We
1753 also figure out some maximum sizes. */
1754 max_contents_size = 0;
1755 max_external_reloc_size = 0;
1756 max_internal_reloc_count = 0;
1757 max_sym_count = 0;
1758 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
1759 {
1760 o->reloc_count = 0;
1761
1762 for (p = o->link_order_head; p != NULL; p = p->next)
1763 {
1764 if (p->type == bfd_section_reloc_link_order
1765 || p->type == bfd_symbol_reloc_link_order)
1766 ++o->reloc_count;
1767 else if (p->type == bfd_indirect_link_order)
1768 {
1769 asection *sec;
1770
1771 sec = p->u.indirect.section;
1772
1773 if (info->relocateable)
1774 o->reloc_count += sec->reloc_count;
1775
1776 if (sec->_raw_size > max_contents_size)
1777 max_contents_size = sec->_raw_size;
1778 if (sec->_cooked_size > max_contents_size)
1779 max_contents_size = sec->_cooked_size;
1780
1781 /* We are interested in just local symbols, not all
1782 symbols. */
1783 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour)
1784 {
1785 size_t sym_count;
1786
1787 if (elf_bad_symtab (sec->owner))
1788 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
1789 / sizeof (Elf_External_Sym));
1790 else
1791 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
1792
1793 if (sym_count > max_sym_count)
1794 max_sym_count = sym_count;
1795
1796 if ((sec->flags & SEC_RELOC) != 0)
1797 {
1798 size_t ext_size;
1799
1800 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
1801 if (ext_size > max_external_reloc_size)
1802 max_external_reloc_size = ext_size;
1803 if (sec->reloc_count > max_internal_reloc_count)
1804 max_internal_reloc_count = sec->reloc_count;
1805 }
1806 }
1807 }
1808 }
1809
1810 if (o->reloc_count > 0)
1811 o->flags |= SEC_RELOC;
1812 else
1813 {
1814 /* Explicitly clear the SEC_RELOC flag. The linker tends to
1815 set it (this is probably a bug) and if it is set
1816 assign_section_numbers will create a reloc section. */
1817 o->flags &=~ SEC_RELOC;
1818 }
1819
1820 /* If the SEC_ALLOC flag is not set, force the section VMA to
1821 zero. This is done in elf_fake_sections as well, but forcing
1822 the VMA to 0 here will ensure that relocs against these
1823 sections are handled correctly. */
1824 if ((o->flags & SEC_ALLOC) == 0)
1825 o->vma = 0;
1826 }
1827
1828 /* Figure out the file positions for everything but the symbol table
1829 and the relocs. We set symcount to force assign_section_numbers
1830 to create a symbol table. */
1831 abfd->symcount = info->strip == strip_all ? 0 : 1;
1832 BFD_ASSERT (! abfd->output_has_begun);
1833 if (! _bfd_elf_compute_section_file_positions (abfd, info))
1834 goto error_return;
1835
1836 /* That created the reloc sections. Set their sizes, and assign
1837 them file positions, and allocate some buffers. */
1838 for (o = abfd->sections; o != NULL; o = o->next)
1839 {
1840 if ((o->flags & SEC_RELOC) != 0)
1841 {
1842 Elf_Internal_Shdr *rel_hdr;
1843 register struct elf_link_hash_entry **p, **pend;
1844
1845 rel_hdr = &elf_section_data (o)->rel_hdr;
1846
1847 rel_hdr->sh_size = rel_hdr->sh_entsize * o->reloc_count;
1848
1849 /* The contents field must last into write_object_contents,
1850 so we allocate it with bfd_alloc rather than malloc. */
1851 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
1852 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
1853 {
1854 bfd_set_error (bfd_error_no_memory);
1855 goto error_return;
1856 }
1857
1858 p = ((struct elf_link_hash_entry **)
1859 malloc (o->reloc_count
1860 * sizeof (struct elf_link_hash_entry *)));
1861 if (p == NULL && o->reloc_count != 0)
1862 {
1863 bfd_set_error (bfd_error_no_memory);
1864 goto error_return;
1865 }
1866 elf_section_data (o)->rel_hashes = p;
1867 pend = p + o->reloc_count;
1868 for (; p < pend; p++)
1869 *p = NULL;
1870
1871 /* Use the reloc_count field as an index when outputting the
1872 relocs. */
1873 o->reloc_count = 0;
1874 }
1875 }
1876
1877 _bfd_elf_assign_file_positions_for_relocs (abfd);
1878
1879 /* We have now assigned file positions for all the sections except
1880 .symtab and .strtab. We start the .symtab section at the current
1881 file position, and write directly to it. We build the .strtab
1882 section in memory. When we add .dynsym support, we will build
1883 that in memory as well (.dynsym is smaller than .symtab). */
1884 abfd->symcount = 0;
1885 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1886 /* sh_name is set in prep_headers. */
1887 symtab_hdr->sh_type = SHT_SYMTAB;
1888 symtab_hdr->sh_flags = 0;
1889 symtab_hdr->sh_addr = 0;
1890 symtab_hdr->sh_size = 0;
1891 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
1892 /* sh_link is set in assign_section_numbers. */
1893 /* sh_info is set below. */
1894 /* sh_offset is set just below. */
1895 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
1896
1897 off = elf_tdata (abfd)->next_file_pos;
1898 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
1899
1900 /* Note that at this point elf_tdata (abfd)->next_file_pos is
1901 incorrect. We do not yet know the size of the .symtab section.
1902 We correct next_file_pos below, after we do know the size. */
1903
1904 /* Allocate a buffer to hold swapped out symbols. This is to avoid
1905 continuously seeking to the right position in the file. */
1906 if (! info->keep_memory || max_sym_count < 20)
1907 finfo.symbuf_size = 20;
1908 else
1909 finfo.symbuf_size = max_sym_count;
1910 finfo.symbuf = ((Elf_External_Sym *)
1911 malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
1912 if (finfo.symbuf == NULL)
1913 {
1914 bfd_set_error (bfd_error_no_memory);
1915 goto error_return;
1916 }
1917
1918 /* Start writing out the symbol table. The first symbol is always a
1919 dummy symbol. */
1920 elfsym.st_value = 0;
1921 elfsym.st_size = 0;
1922 elfsym.st_info = 0;
1923 elfsym.st_other = 0;
1924 elfsym.st_shndx = SHN_UNDEF;
1925 if (! elf_link_output_sym (&finfo, (const char *) NULL,
1926 &elfsym, bfd_und_section_ptr))
1927 goto error_return;
1928
1929 #if 0
1930 /* Some standard ELF linkers do this, but we don't because it causes
1931 bootstrap comparison failures. */
1932 /* Output a file symbol for the output file as the second symbol.
1933 We output this even if we are discarding local symbols, although
1934 I'm not sure if this is correct. */
1935 elfsym.st_value = 0;
1936 elfsym.st_size = 0;
1937 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
1938 elfsym.st_other = 0;
1939 elfsym.st_shndx = SHN_ABS;
1940 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
1941 &elfsym, bfd_abs_section_ptr))
1942 goto error_return;
1943 #endif
1944
1945 /* Output a symbol for each section. We output these even if we are
1946 discarding local symbols, since they are used for relocs. These
1947 symbols have no names. We store the index of each one in the
1948 index field of the section, so that we can find it again when
1949 outputting relocs. */
1950 elfsym.st_value = 0;
1951 elfsym.st_size = 0;
1952 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
1953 elfsym.st_other = 0;
1954 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
1955 {
1956 o = section_from_elf_index (abfd, i);
1957 if (o != NULL)
1958 o->target_index = abfd->symcount;
1959 elfsym.st_shndx = i;
1960 if (! elf_link_output_sym (&finfo, (const char *) NULL,
1961 &elfsym, o))
1962 goto error_return;
1963 }
1964
1965 /* Allocate some memory to hold information read in from the input
1966 files. */
1967 finfo.contents = (bfd_byte *) malloc (max_contents_size);
1968 finfo.external_relocs = (PTR) malloc (max_external_reloc_size);
1969 finfo.internal_relocs = ((Elf_Internal_Rela *)
1970 malloc (max_internal_reloc_count
1971 * sizeof (Elf_Internal_Rela)));
1972 finfo.external_syms = ((Elf_External_Sym *)
1973 malloc (max_sym_count * sizeof (Elf_External_Sym)));
1974 finfo.internal_syms = ((Elf_Internal_Sym *)
1975 malloc (max_sym_count * sizeof (Elf_Internal_Sym)));
1976 finfo.indices = (long *) malloc (max_sym_count * sizeof (long));
1977 finfo.sections = (asection **) malloc (max_sym_count * sizeof (asection *));
1978 if ((finfo.contents == NULL && max_contents_size != 0)
1979 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
1980 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
1981 || (finfo.external_syms == NULL && max_sym_count != 0)
1982 || (finfo.internal_syms == NULL && max_sym_count != 0)
1983 || (finfo.indices == NULL && max_sym_count != 0)
1984 || (finfo.sections == NULL && max_sym_count != 0))
1985 {
1986 bfd_set_error (bfd_error_no_memory);
1987 goto error_return;
1988 }
1989
1990 /* Since ELF permits relocations to be against local symbols, we
1991 must have the local symbols available when we do the relocations.
1992 Since we would rather only read the local symbols once, and we
1993 would rather not keep them in memory, we handle all the
1994 relocations for a single input file at the same time.
1995
1996 Unfortunately, there is no way to know the total number of local
1997 symbols until we have seen all of them, and the local symbol
1998 indices precede the global symbol indices. This means that when
1999 we are generating relocateable output, and we see a reloc against
2000 a global symbol, we can not know the symbol index until we have
2001 finished examining all the local symbols to see which ones we are
2002 going to output. To deal with this, we keep the relocations in
2003 memory, and don't output them until the end of the link. This is
2004 an unfortunate waste of memory, but I don't see a good way around
2005 it. Fortunately, it only happens when performing a relocateable
2006 link, which is not the common case. FIXME: If keep_memory is set
2007 we could write the relocs out and then read them again; I don't
2008 know how bad the memory loss will be. */
2009
2010 for (sub = info->input_bfds; sub != NULL; sub = sub->next)
2011 sub->output_has_begun = false;
2012 for (o = abfd->sections; o != NULL; o = o->next)
2013 {
2014 for (p = o->link_order_head; p != NULL; p = p->next)
2015 {
2016 if (p->type == bfd_indirect_link_order
2017 && (bfd_get_flavour (p->u.indirect.section->owner)
2018 == bfd_target_elf_flavour))
2019 {
2020 sub = p->u.indirect.section->owner;
2021 if (! sub->output_has_begun)
2022 {
2023 if (! elf_link_input_bfd (&finfo, sub))
2024 goto error_return;
2025 sub->output_has_begun = true;
2026 }
2027 }
2028 else if (p->type == bfd_section_reloc_link_order
2029 || p->type == bfd_symbol_reloc_link_order)
2030 {
2031 if (! elf_reloc_link_order (abfd, info, o, p))
2032 goto error_return;
2033 }
2034 else
2035 {
2036 if (! _bfd_default_link_order (abfd, info, o, p))
2037 goto error_return;
2038 }
2039 }
2040 }
2041
2042 /* That wrote out all the local symbols. Finish up the symbol table
2043 with the global symbols. */
2044
2045 /* The sh_info field records the index of the first non local
2046 symbol. */
2047 symtab_hdr->sh_info = abfd->symcount;
2048 if (dynamic)
2049 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info = 1;
2050
2051 /* We get the global symbols from the hash table. */
2052 eif.failed = false;
2053 eif.finfo = &finfo;
2054 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
2055 (PTR) &eif);
2056 if (eif.failed)
2057 return false;
2058
2059 /* Flush all symbols to the file. */
2060 if (! elf_link_flush_output_syms (&finfo))
2061 return false;
2062
2063 /* Now we know the size of the symtab section. */
2064 off += symtab_hdr->sh_size;
2065
2066 /* Finish up and write out the symbol string table (.strtab)
2067 section. */
2068 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
2069 /* sh_name was set in prep_headers. */
2070 symstrtab_hdr->sh_type = SHT_STRTAB;
2071 symstrtab_hdr->sh_flags = 0;
2072 symstrtab_hdr->sh_addr = 0;
2073 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
2074 symstrtab_hdr->sh_entsize = 0;
2075 symstrtab_hdr->sh_link = 0;
2076 symstrtab_hdr->sh_info = 0;
2077 /* sh_offset is set just below. */
2078 symstrtab_hdr->sh_addralign = 1;
2079
2080 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
2081 elf_tdata (abfd)->next_file_pos = off;
2082
2083 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
2084 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
2085 return false;
2086
2087 /* Adjust the relocs to have the correct symbol indices. */
2088 for (o = abfd->sections; o != NULL; o = o->next)
2089 {
2090 struct elf_link_hash_entry **rel_hash;
2091 Elf_Internal_Shdr *rel_hdr;
2092
2093 if ((o->flags & SEC_RELOC) == 0)
2094 continue;
2095
2096 rel_hash = elf_section_data (o)->rel_hashes;
2097 rel_hdr = &elf_section_data (o)->rel_hdr;
2098 for (i = 0; i < o->reloc_count; i++, rel_hash++)
2099 {
2100 if (*rel_hash == NULL)
2101 continue;
2102
2103 BFD_ASSERT ((*rel_hash)->indx >= 0);
2104
2105 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
2106 {
2107 Elf_External_Rel *erel;
2108 Elf_Internal_Rel irel;
2109
2110 erel = (Elf_External_Rel *) rel_hdr->contents + i;
2111 elf_swap_reloc_in (abfd, erel, &irel);
2112 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
2113 ELF_R_TYPE (irel.r_info));
2114 elf_swap_reloc_out (abfd, &irel, erel);
2115 }
2116 else
2117 {
2118 Elf_External_Rela *erela;
2119 Elf_Internal_Rela irela;
2120
2121 BFD_ASSERT (rel_hdr->sh_entsize
2122 == sizeof (Elf_External_Rela));
2123
2124 erela = (Elf_External_Rela *) rel_hdr->contents + i;
2125 elf_swap_reloca_in (abfd, erela, &irela);
2126 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
2127 ELF_R_TYPE (irela.r_info));
2128 elf_swap_reloca_out (abfd, &irela, erela);
2129 }
2130 }
2131
2132 /* Set the reloc_count field to 0 to prevent write_relocs from
2133 trying to swap the relocs out itself. */
2134 o->reloc_count = 0;
2135 }
2136
2137 /* If we are linking against a dynamic object, or generating a
2138 shared library, finish up the dynamic linking information. */
2139 if (dynamic)
2140 {
2141 Elf_External_Dyn *dyncon, *dynconend;
2142
2143 /* Fix up .dynamic entries. */
2144 o = bfd_get_section_by_name (dynobj, ".dynamic");
2145 BFD_ASSERT (o != NULL);
2146
2147 dyncon = (Elf_External_Dyn *) o->contents;
2148 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
2149 for (; dyncon < dynconend; dyncon++)
2150 {
2151 Elf_Internal_Dyn dyn;
2152 const char *name;
2153 unsigned int type;
2154
2155 elf_swap_dyn_in (dynobj, dyncon, &dyn);
2156
2157 switch (dyn.d_tag)
2158 {
2159 default:
2160 break;
2161
2162 /* SVR4 linkers seem to set DT_INIT and DT_FINI based on
2163 magic _init and _fini symbols. This is pretty ugly,
2164 but we are compatible. */
2165 case DT_INIT:
2166 name = "_init";
2167 goto get_sym;
2168 case DT_FINI:
2169 name = "_fini";
2170 get_sym:
2171 {
2172 struct elf_link_hash_entry *h;
2173
2174 h = elf_link_hash_lookup (elf_hash_table (info), name,
2175 false, false, true);
2176 if (h != NULL
2177 && (h->root.type == bfd_link_hash_defined
2178 || h->root.type == bfd_link_hash_defweak))
2179 {
2180 dyn.d_un.d_val = h->root.u.def.value;
2181 o = h->root.u.def.section;
2182 if (o->output_section != NULL)
2183 dyn.d_un.d_val += (o->output_section->vma
2184 + o->output_offset);
2185 else
2186 {
2187 /* The symbol is imported from another shared
2188 library and does not apply to this one. */
2189 dyn.d_un.d_val = 0;
2190 }
2191
2192 elf_swap_dyn_out (dynobj, &dyn, dyncon);
2193 }
2194 }
2195 break;
2196
2197 case DT_HASH:
2198 name = ".hash";
2199 goto get_vma;
2200 case DT_STRTAB:
2201 name = ".dynstr";
2202 goto get_vma;
2203 case DT_SYMTAB:
2204 name = ".dynsym";
2205 get_vma:
2206 o = bfd_get_section_by_name (abfd, name);
2207 BFD_ASSERT (o != NULL);
2208 dyn.d_un.d_ptr = o->vma;
2209 elf_swap_dyn_out (dynobj, &dyn, dyncon);
2210 break;
2211
2212 case DT_REL:
2213 case DT_RELA:
2214 case DT_RELSZ:
2215 case DT_RELASZ:
2216 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
2217 type = SHT_REL;
2218 else
2219 type = SHT_RELA;
2220 dyn.d_un.d_val = 0;
2221 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
2222 {
2223 Elf_Internal_Shdr *hdr;
2224
2225 hdr = elf_elfsections (abfd)[i];
2226 if (hdr->sh_type == type
2227 && (hdr->sh_flags & SHF_ALLOC) != 0)
2228 {
2229 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
2230 dyn.d_un.d_val += hdr->sh_size;
2231 else
2232 {
2233 if (dyn.d_un.d_val == 0
2234 || hdr->sh_addr < dyn.d_un.d_val)
2235 dyn.d_un.d_val = hdr->sh_addr;
2236 }
2237 }
2238 }
2239 elf_swap_dyn_out (dynobj, &dyn, dyncon);
2240 break;
2241 }
2242 }
2243 }
2244
2245 /* If we have created any dynamic sections, then output them. */
2246 if (dynobj != NULL)
2247 {
2248 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
2249 goto error_return;
2250
2251 for (o = dynobj->sections; o != NULL; o = o->next)
2252 {
2253 if ((o->flags & SEC_HAS_CONTENTS) == 0
2254 || o->_raw_size == 0)
2255 continue;
2256 if ((o->flags & SEC_IN_MEMORY) == 0)
2257 {
2258 /* At this point, we are only interested in sections
2259 created by elf_link_create_dynamic_sections. FIXME:
2260 This test is fragile. */
2261 continue;
2262 }
2263 if ((elf_section_data (o->output_section)->this_hdr.sh_type
2264 != SHT_STRTAB)
2265 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
2266 {
2267 if (! bfd_set_section_contents (abfd, o->output_section,
2268 o->contents, o->output_offset,
2269 o->_raw_size))
2270 goto error_return;
2271 }
2272 else
2273 {
2274 file_ptr off;
2275
2276 /* The contents of the .dynstr section are actually in a
2277 stringtab. */
2278 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
2279 if (bfd_seek (abfd, off, SEEK_SET) != 0
2280 || ! _bfd_stringtab_emit (abfd,
2281 elf_hash_table (info)->dynstr))
2282 goto error_return;
2283 }
2284 }
2285 }
2286
2287 if (finfo.symstrtab != NULL)
2288 _bfd_stringtab_free (finfo.symstrtab);
2289 if (finfo.contents != NULL)
2290 free (finfo.contents);
2291 if (finfo.external_relocs != NULL)
2292 free (finfo.external_relocs);
2293 if (finfo.internal_relocs != NULL)
2294 free (finfo.internal_relocs);
2295 if (finfo.external_syms != NULL)
2296 free (finfo.external_syms);
2297 if (finfo.internal_syms != NULL)
2298 free (finfo.internal_syms);
2299 if (finfo.indices != NULL)
2300 free (finfo.indices);
2301 if (finfo.sections != NULL)
2302 free (finfo.sections);
2303 if (finfo.symbuf != NULL)
2304 free (finfo.symbuf);
2305 for (o = abfd->sections; o != NULL; o = o->next)
2306 {
2307 if ((o->flags & SEC_RELOC) != 0
2308 && elf_section_data (o)->rel_hashes != NULL)
2309 free (elf_section_data (o)->rel_hashes);
2310 }
2311
2312 elf_tdata (abfd)->linker = true;
2313
2314 return true;
2315
2316 error_return:
2317 if (finfo.symstrtab != NULL)
2318 _bfd_stringtab_free (finfo.symstrtab);
2319 if (finfo.contents != NULL)
2320 free (finfo.contents);
2321 if (finfo.external_relocs != NULL)
2322 free (finfo.external_relocs);
2323 if (finfo.internal_relocs != NULL)
2324 free (finfo.internal_relocs);
2325 if (finfo.external_syms != NULL)
2326 free (finfo.external_syms);
2327 if (finfo.internal_syms != NULL)
2328 free (finfo.internal_syms);
2329 if (finfo.indices != NULL)
2330 free (finfo.indices);
2331 if (finfo.sections != NULL)
2332 free (finfo.sections);
2333 if (finfo.symbuf != NULL)
2334 free (finfo.symbuf);
2335 for (o = abfd->sections; o != NULL; o = o->next)
2336 {
2337 if ((o->flags & SEC_RELOC) != 0
2338 && elf_section_data (o)->rel_hashes != NULL)
2339 free (elf_section_data (o)->rel_hashes);
2340 }
2341
2342 return false;
2343 }
2344
2345 /* Add a symbol to the output symbol table. */
2346
2347 static boolean
2348 elf_link_output_sym (finfo, name, elfsym, input_sec)
2349 struct elf_final_link_info *finfo;
2350 const char *name;
2351 Elf_Internal_Sym *elfsym;
2352 asection *input_sec;
2353 {
2354 boolean (*output_symbol_hook) PARAMS ((bfd *,
2355 struct bfd_link_info *info,
2356 const char *,
2357 Elf_Internal_Sym *,
2358 asection *));
2359
2360 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
2361 elf_backend_link_output_symbol_hook;
2362 if (output_symbol_hook != NULL)
2363 {
2364 if (! ((*output_symbol_hook)
2365 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
2366 return false;
2367 }
2368
2369 if (name == (const char *) NULL || *name == '\0')
2370 elfsym->st_name = 0;
2371 else
2372 {
2373 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
2374 name, true,
2375 false);
2376 if (elfsym->st_name == (unsigned long) -1)
2377 return false;
2378 }
2379
2380 if (finfo->symbuf_count >= finfo->symbuf_size)
2381 {
2382 if (! elf_link_flush_output_syms (finfo))
2383 return false;
2384 }
2385
2386 elf_swap_symbol_out (finfo->output_bfd, elfsym,
2387 (PTR) (finfo->symbuf + finfo->symbuf_count));
2388 ++finfo->symbuf_count;
2389
2390 ++finfo->output_bfd->symcount;
2391
2392 return true;
2393 }
2394
2395 /* Flush the output symbols to the file. */
2396
2397 static boolean
2398 elf_link_flush_output_syms (finfo)
2399 struct elf_final_link_info *finfo;
2400 {
2401 Elf_Internal_Shdr *symtab;
2402
2403 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
2404
2405 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
2406 SEEK_SET) != 0
2407 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
2408 sizeof (Elf_External_Sym), finfo->output_bfd)
2409 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
2410 return false;
2411
2412 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
2413
2414 finfo->symbuf_count = 0;
2415
2416 return true;
2417 }
2418
2419 /* Add an external symbol to the symbol table. This is called from
2420 the hash table traversal routine. */
2421
2422 static boolean
2423 elf_link_output_extsym (h, data)
2424 struct elf_link_hash_entry *h;
2425 PTR data;
2426 {
2427 struct elf_finfo_failed *eif = (struct elf_finfo_failed *) data;
2428 struct elf_final_link_info *finfo = eif->finfo;
2429 boolean strip;
2430 Elf_Internal_Sym sym;
2431 asection *input_sec;
2432
2433 /* If we are not creating a shared library, and this symbol is
2434 referenced by a shared library but is not defined anywhere, then
2435 warn that it is undefined. If we do not do this, the runtime
2436 linker will complain that the symbol is undefined when the
2437 program is run. We don't have to worry about symbols that are
2438 referenced by regular files, because we will already have issued
2439 warnings for them. */
2440 if (! finfo->info->relocateable
2441 && ! finfo->info->shared
2442 && h->root.type == bfd_link_hash_undefined
2443 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
2444 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
2445 {
2446 if (! ((*finfo->info->callbacks->undefined_symbol)
2447 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
2448 (asection *) NULL, 0)))
2449 {
2450 eif->failed = true;
2451 return false;
2452 }
2453 }
2454
2455 /* We don't want to output symbols that have never been mentioned by
2456 a regular file, or that we have been told to strip. However, if
2457 h->indx is set to -2, the symbol is used by a reloc and we must
2458 output it. */
2459 if (h->indx == -2)
2460 strip = false;
2461 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2462 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
2463 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
2464 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
2465 strip = true;
2466 else if (finfo->info->strip == strip_all
2467 || (finfo->info->strip == strip_some
2468 && bfd_hash_lookup (finfo->info->keep_hash,
2469 h->root.root.string,
2470 false, false) == NULL))
2471 strip = true;
2472 else
2473 strip = false;
2474
2475 /* If we're stripping it, and it's not a dynamic symbol, there's
2476 nothing else to do. */
2477 if (strip && h->dynindx == -1)
2478 return true;
2479
2480 sym.st_value = 0;
2481 sym.st_size = h->size;
2482 sym.st_other = 0;
2483 if (h->root.type == bfd_link_hash_undefweak
2484 || h->root.type == bfd_link_hash_defweak)
2485 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
2486 else
2487 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
2488
2489 switch (h->root.type)
2490 {
2491 default:
2492 case bfd_link_hash_new:
2493 abort ();
2494 return false;
2495
2496 case bfd_link_hash_undefined:
2497 input_sec = bfd_und_section_ptr;
2498 sym.st_shndx = SHN_UNDEF;
2499 break;
2500
2501 case bfd_link_hash_undefweak:
2502 input_sec = bfd_und_section_ptr;
2503 sym.st_shndx = SHN_UNDEF;
2504 break;
2505
2506 case bfd_link_hash_defined:
2507 case bfd_link_hash_defweak:
2508 {
2509 input_sec = h->root.u.def.section;
2510 if (input_sec->output_section != NULL)
2511 {
2512 sym.st_shndx =
2513 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
2514 input_sec->output_section);
2515 if (sym.st_shndx == (unsigned short) -1)
2516 {
2517 eif->failed = true;
2518 return false;
2519 }
2520
2521 /* ELF symbols in relocateable files are section relative,
2522 but in nonrelocateable files they are virtual
2523 addresses. */
2524 sym.st_value = h->root.u.def.value + input_sec->output_offset;
2525 if (! finfo->info->relocateable)
2526 sym.st_value += input_sec->output_section->vma;
2527 }
2528 else
2529 {
2530 BFD_ASSERT ((bfd_get_flavour (input_sec->owner)
2531 == bfd_target_elf_flavour)
2532 && elf_elfheader (input_sec->owner)->e_type == ET_DYN);
2533 sym.st_shndx = SHN_UNDEF;
2534 input_sec = bfd_und_section_ptr;
2535 }
2536 }
2537 break;
2538
2539 case bfd_link_hash_common:
2540 input_sec = bfd_com_section_ptr;
2541 sym.st_shndx = SHN_COMMON;
2542 sym.st_value = 1 << h->root.u.c.p->alignment_power;
2543 break;
2544
2545 case bfd_link_hash_indirect:
2546 case bfd_link_hash_warning:
2547 return (elf_link_output_extsym
2548 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
2549 }
2550
2551 /* If this symbol should be put in the .dynsym section, then put it
2552 there now. We have already know the symbol index. We also fill
2553 in the entry in the .hash section. */
2554 if (h->dynindx != -1
2555 && elf_hash_table (finfo->info)->dynamic_sections_created)
2556 {
2557 struct elf_backend_data *bed;
2558 size_t bucketcount;
2559 size_t bucket;
2560 bfd_byte *bucketpos;
2561 bfd_vma chain;
2562
2563 sym.st_name = h->dynstr_index;
2564
2565 /* Give the processor backend a chance to tweak the symbol
2566 value, and also to finish up anything that needs to be done
2567 for this symbol. */
2568 bed = get_elf_backend_data (finfo->output_bfd);
2569 if (! ((*bed->elf_backend_finish_dynamic_symbol)
2570 (finfo->output_bfd, finfo->info, h, &sym)))
2571 {
2572 eif->failed = true;
2573 return false;
2574 }
2575
2576 elf_swap_symbol_out (finfo->output_bfd, &sym,
2577 (PTR) (((Elf_External_Sym *)
2578 finfo->dynsym_sec->contents)
2579 + h->dynindx));
2580
2581 bucketcount = elf_hash_table (finfo->info)->bucketcount;
2582 bucket = (bfd_elf_hash ((const unsigned char *) h->root.root.string)
2583 % bucketcount);
2584 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
2585 + (bucket + 2) * (ARCH_SIZE / 8));
2586 chain = get_word (finfo->output_bfd, bucketpos);
2587 put_word (finfo->output_bfd, h->dynindx, bucketpos);
2588 put_word (finfo->output_bfd, chain,
2589 ((bfd_byte *) finfo->hash_sec->contents
2590 + (bucketcount + 2 + h->dynindx) * (ARCH_SIZE / 8)));
2591 }
2592
2593 /* If we're stripping it, then it was just a dynamic symbol, and
2594 there's nothing else to do. */
2595 if (strip)
2596 return true;
2597
2598 h->indx = finfo->output_bfd->symcount;
2599
2600 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
2601 {
2602 eif->failed = true;
2603 return false;
2604 }
2605
2606 return true;
2607 }
2608
2609 /* Link an input file into the linker output file. This function
2610 handles all the sections and relocations of the input file at once.
2611 This is so that we only have to read the local symbols once, and
2612 don't have to keep them in memory. */
2613
2614 static boolean
2615 elf_link_input_bfd (finfo, input_bfd)
2616 struct elf_final_link_info *finfo;
2617 bfd *input_bfd;
2618 {
2619 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
2620 bfd *, asection *, bfd_byte *,
2621 Elf_Internal_Rela *,
2622 Elf_Internal_Sym *, asection **));
2623 bfd *output_bfd;
2624 Elf_Internal_Shdr *symtab_hdr;
2625 size_t locsymcount;
2626 size_t extsymoff;
2627 Elf_External_Sym *esym;
2628 Elf_External_Sym *esymend;
2629 Elf_Internal_Sym *isym;
2630 long *pindex;
2631 asection **ppsection;
2632 asection *o;
2633
2634 output_bfd = finfo->output_bfd;
2635 relocate_section =
2636 get_elf_backend_data (output_bfd)->elf_backend_relocate_section;
2637
2638 /* If this is a dynamic object, we don't want to do anything here:
2639 we don't want the local symbols, and we don't want the section
2640 contents. */
2641 if (elf_elfheader (input_bfd)->e_type == ET_DYN)
2642 return true;
2643
2644 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2645 if (elf_bad_symtab (input_bfd))
2646 {
2647 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
2648 extsymoff = 0;
2649 }
2650 else
2651 {
2652 locsymcount = symtab_hdr->sh_info;
2653 extsymoff = symtab_hdr->sh_info;
2654 }
2655
2656 /* Read the local symbols. */
2657 if (locsymcount > 0
2658 && (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
2659 || (bfd_read (finfo->external_syms, sizeof (Elf_External_Sym),
2660 locsymcount, input_bfd)
2661 != locsymcount * sizeof (Elf_External_Sym))))
2662 return false;
2663
2664 /* Swap in the local symbols and write out the ones which we know
2665 are going into the output file. */
2666 esym = finfo->external_syms;
2667 esymend = esym + locsymcount;
2668 isym = finfo->internal_syms;
2669 pindex = finfo->indices;
2670 ppsection = finfo->sections;
2671 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
2672 {
2673 asection *isec;
2674 const char *name;
2675 Elf_Internal_Sym osym;
2676
2677 elf_swap_symbol_in (input_bfd, esym, isym);
2678 *pindex = -1;
2679
2680 if (elf_bad_symtab (input_bfd))
2681 {
2682 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
2683 {
2684 *ppsection = NULL;
2685 continue;
2686 }
2687 }
2688
2689 if (isym->st_shndx == SHN_UNDEF)
2690 isec = bfd_und_section_ptr;
2691 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
2692 isec = section_from_elf_index (input_bfd, isym->st_shndx);
2693 else if (isym->st_shndx == SHN_ABS)
2694 isec = bfd_abs_section_ptr;
2695 else if (isym->st_shndx == SHN_COMMON)
2696 isec = bfd_com_section_ptr;
2697 else
2698 {
2699 /* Who knows? */
2700 isec = NULL;
2701 }
2702
2703 *ppsection = isec;
2704
2705 /* Don't output the first, undefined, symbol. */
2706 if (esym == finfo->external_syms)
2707 continue;
2708
2709 /* If we are stripping all symbols, we don't want to output this
2710 one. */
2711 if (finfo->info->strip == strip_all)
2712 continue;
2713
2714 /* We never output section symbols. Instead, we use the section
2715 symbol of the corresponding section in the output file. */
2716 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
2717 continue;
2718
2719 /* If we are discarding all local symbols, we don't want to
2720 output this one. If we are generating a relocateable output
2721 file, then some of the local symbols may be required by
2722 relocs; we output them below as we discover that they are
2723 needed. */
2724 if (finfo->info->discard == discard_all)
2725 continue;
2726
2727 /* Get the name of the symbol. */
2728 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
2729 isym->st_name);
2730 if (name == NULL)
2731 return false;
2732
2733 /* See if we are discarding symbols with this name. */
2734 if ((finfo->info->strip == strip_some
2735 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
2736 == NULL))
2737 || (finfo->info->discard == discard_l
2738 && strncmp (name, finfo->info->lprefix,
2739 finfo->info->lprefix_len) == 0))
2740 continue;
2741
2742 /* If we get here, we are going to output this symbol. */
2743
2744 osym = *isym;
2745
2746 /* Adjust the section index for the output file. */
2747 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
2748 isec->output_section);
2749 if (osym.st_shndx == (unsigned short) -1)
2750 return false;
2751
2752 *pindex = output_bfd->symcount;
2753
2754 /* ELF symbols in relocateable files are section relative, but
2755 in executable files they are virtual addresses. Note that
2756 this code assumes that all ELF sections have an associated
2757 BFD section with a reasonable value for output_offset; below
2758 we assume that they also have a reasonable value for
2759 output_section. Any special sections must be set up to meet
2760 these requirements. */
2761 osym.st_value += isec->output_offset;
2762 if (! finfo->info->relocateable)
2763 osym.st_value += isec->output_section->vma;
2764
2765 if (! elf_link_output_sym (finfo, name, &osym, isec))
2766 return false;
2767 }
2768
2769 /* Relocate the contents of each section. */
2770 for (o = input_bfd->sections; o != NULL; o = o->next)
2771 {
2772 if ((o->flags & SEC_HAS_CONTENTS) == 0)
2773 continue;
2774
2775 if ((o->flags & SEC_IN_MEMORY) != 0
2776 && input_bfd == elf_hash_table (finfo->info)->dynobj)
2777 {
2778 /* Section was created by elf_link_create_dynamic_sections.
2779 FIXME: This test is fragile. */
2780 continue;
2781 }
2782
2783 /* Read the contents of the section. */
2784 if (! bfd_get_section_contents (input_bfd, o, finfo->contents,
2785 (file_ptr) 0, o->_raw_size))
2786 return false;
2787
2788 if ((o->flags & SEC_RELOC) != 0)
2789 {
2790 Elf_Internal_Rela *internal_relocs;
2791
2792 /* Get the swapped relocs. */
2793 internal_relocs = elf_link_read_relocs (input_bfd, o,
2794 finfo->external_relocs,
2795 finfo->internal_relocs,
2796 false);
2797 if (internal_relocs == NULL
2798 && o->reloc_count > 0)
2799 return false;
2800
2801 /* Relocate the section by invoking a back end routine.
2802
2803 The back end routine is responsible for adjusting the
2804 section contents as necessary, and (if using Rela relocs
2805 and generating a relocateable output file) adjusting the
2806 reloc addend as necessary.
2807
2808 The back end routine does not have to worry about setting
2809 the reloc address or the reloc symbol index.
2810
2811 The back end routine is given a pointer to the swapped in
2812 internal symbols, and can access the hash table entries
2813 for the external symbols via elf_sym_hashes (input_bfd).
2814
2815 When generating relocateable output, the back end routine
2816 must handle STB_LOCAL/STT_SECTION symbols specially. The
2817 output symbol is going to be a section symbol
2818 corresponding to the output section, which will require
2819 the addend to be adjusted. */
2820
2821 if (! (*relocate_section) (output_bfd, finfo->info,
2822 input_bfd, o,
2823 finfo->contents,
2824 internal_relocs,
2825 finfo->internal_syms,
2826 finfo->sections))
2827 return false;
2828
2829 if (finfo->info->relocateable)
2830 {
2831 Elf_Internal_Rela *irela;
2832 Elf_Internal_Rela *irelaend;
2833 struct elf_link_hash_entry **rel_hash;
2834 Elf_Internal_Shdr *input_rel_hdr;
2835 Elf_Internal_Shdr *output_rel_hdr;
2836
2837 /* Adjust the reloc addresses and symbol indices. */
2838
2839 irela = internal_relocs;
2840 irelaend = irela + o->reloc_count;
2841 rel_hash = (elf_section_data (o->output_section)->rel_hashes
2842 + o->output_section->reloc_count);
2843 for (; irela < irelaend; irela++, rel_hash++)
2844 {
2845 unsigned long r_symndx;
2846 Elf_Internal_Sym *isym;
2847 asection *sec;
2848
2849 irela->r_offset += o->output_offset;
2850
2851 r_symndx = ELF_R_SYM (irela->r_info);
2852
2853 if (r_symndx == 0)
2854 continue;
2855
2856 if (r_symndx >= locsymcount
2857 || (elf_bad_symtab (input_bfd)
2858 && finfo->sections[r_symndx] == NULL))
2859 {
2860 long indx;
2861
2862 /* This is a reloc against a global symbol. We
2863 have not yet output all the local symbols, so
2864 we do not know the symbol index of any global
2865 symbol. We set the rel_hash entry for this
2866 reloc to point to the global hash table entry
2867 for this symbol. The symbol index is then
2868 set at the end of elf_bfd_final_link. */
2869 indx = r_symndx - extsymoff;
2870 *rel_hash = elf_sym_hashes (input_bfd)[indx];
2871
2872 /* Setting the index to -2 tells
2873 elf_link_output_extsym that this symbol is
2874 used by a reloc. */
2875 BFD_ASSERT ((*rel_hash)->indx < 0);
2876 (*rel_hash)->indx = -2;
2877
2878 continue;
2879 }
2880
2881 /* This is a reloc against a local symbol. */
2882
2883 *rel_hash = NULL;
2884 isym = finfo->internal_syms + r_symndx;
2885 sec = finfo->sections[r_symndx];
2886 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
2887 {
2888 /* I suppose the backend ought to fill in the
2889 section of any STT_SECTION symbol against a
2890 processor specific section. */
2891 if (sec != NULL && bfd_is_abs_section (sec))
2892 r_symndx = 0;
2893 else if (sec == NULL || sec->owner == NULL)
2894 {
2895 bfd_set_error (bfd_error_bad_value);
2896 return false;
2897 }
2898 else
2899 {
2900 r_symndx = sec->output_section->target_index;
2901 BFD_ASSERT (r_symndx != 0);
2902 }
2903 }
2904 else
2905 {
2906 if (finfo->indices[r_symndx] == -1)
2907 {
2908 unsigned long link;
2909 const char *name;
2910 asection *osec;
2911
2912 if (finfo->info->strip == strip_all)
2913 {
2914 /* You can't do ld -r -s. */
2915 bfd_set_error (bfd_error_invalid_operation);
2916 return false;
2917 }
2918
2919 /* This symbol was skipped earlier, but
2920 since it is needed by a reloc, we
2921 must output it now. */
2922 link = symtab_hdr->sh_link;
2923 name = bfd_elf_string_from_elf_section (input_bfd,
2924 link,
2925 isym->st_name);
2926 if (name == NULL)
2927 return false;
2928
2929 osec = sec->output_section;
2930 isym->st_shndx =
2931 _bfd_elf_section_from_bfd_section (output_bfd,
2932 osec);
2933 if (isym->st_shndx == (unsigned short) -1)
2934 return false;
2935
2936 isym->st_value += sec->output_offset;
2937 if (! finfo->info->relocateable)
2938 isym->st_value += osec->vma;
2939
2940 finfo->indices[r_symndx] = output_bfd->symcount;
2941
2942 if (! elf_link_output_sym (finfo, name, isym, sec))
2943 return false;
2944 }
2945
2946 r_symndx = finfo->indices[r_symndx];
2947 }
2948
2949 irela->r_info = ELF_R_INFO (r_symndx,
2950 ELF_R_TYPE (irela->r_info));
2951 }
2952
2953 /* Swap out the relocs. */
2954 input_rel_hdr = &elf_section_data (o)->rel_hdr;
2955 output_rel_hdr = &elf_section_data (o->output_section)->rel_hdr;
2956 BFD_ASSERT (output_rel_hdr->sh_entsize
2957 == input_rel_hdr->sh_entsize);
2958 irela = internal_relocs;
2959 irelaend = irela + o->reloc_count;
2960 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
2961 {
2962 Elf_External_Rel *erel;
2963
2964 erel = ((Elf_External_Rel *) output_rel_hdr->contents
2965 + o->output_section->reloc_count);
2966 for (; irela < irelaend; irela++, erel++)
2967 {
2968 Elf_Internal_Rel irel;
2969
2970 irel.r_offset = irela->r_offset;
2971 irel.r_info = irela->r_info;
2972 BFD_ASSERT (irela->r_addend == 0);
2973 elf_swap_reloc_out (output_bfd, &irel, erel);
2974 }
2975 }
2976 else
2977 {
2978 Elf_External_Rela *erela;
2979
2980 BFD_ASSERT (input_rel_hdr->sh_entsize
2981 == sizeof (Elf_External_Rela));
2982 erela = ((Elf_External_Rela *) output_rel_hdr->contents
2983 + o->output_section->reloc_count);
2984 for (; irela < irelaend; irela++, erela++)
2985 elf_swap_reloca_out (output_bfd, irela, erela);
2986 }
2987
2988 o->output_section->reloc_count += o->reloc_count;
2989 }
2990 }
2991
2992 /* Write out the modified section contents. */
2993 if (! bfd_set_section_contents (output_bfd, o->output_section,
2994 finfo->contents, o->output_offset,
2995 (o->_cooked_size != 0
2996 ? o->_cooked_size
2997 : o->_raw_size)))
2998 return false;
2999 }
3000
3001 return true;
3002 }
3003
3004 /* Generate a reloc when linking an ELF file. This is a reloc
3005 requested by the linker, and does come from any input file. This
3006 is used to build constructor and destructor tables when linking
3007 with -Ur. */
3008
3009 static boolean
3010 elf_reloc_link_order (output_bfd, info, output_section, link_order)
3011 bfd *output_bfd;
3012 struct bfd_link_info *info;
3013 asection *output_section;
3014 struct bfd_link_order *link_order;
3015 {
3016 reloc_howto_type *howto;
3017 long indx;
3018 bfd_vma offset;
3019 struct elf_link_hash_entry **rel_hash_ptr;
3020 Elf_Internal_Shdr *rel_hdr;
3021
3022 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
3023 if (howto == NULL)
3024 {
3025 bfd_set_error (bfd_error_bad_value);
3026 return false;
3027 }
3028
3029 /* If this is an inplace reloc, we must write the addend into the
3030 object file. */
3031 if (howto->partial_inplace
3032 && link_order->u.reloc.p->addend != 0)
3033 {
3034 bfd_size_type size;
3035 bfd_reloc_status_type rstat;
3036 bfd_byte *buf;
3037 boolean ok;
3038
3039 size = bfd_get_reloc_size (howto);
3040 buf = (bfd_byte *) bfd_zmalloc (size);
3041 if (buf == (bfd_byte *) NULL)
3042 {
3043 bfd_set_error (bfd_error_no_memory);
3044 return false;
3045 }
3046 rstat = _bfd_relocate_contents (howto, output_bfd,
3047 link_order->u.reloc.p->addend, buf);
3048 switch (rstat)
3049 {
3050 case bfd_reloc_ok:
3051 break;
3052 default:
3053 case bfd_reloc_outofrange:
3054 abort ();
3055 case bfd_reloc_overflow:
3056 if (! ((*info->callbacks->reloc_overflow)
3057 (info,
3058 (link_order->type == bfd_section_reloc_link_order
3059 ? bfd_section_name (output_bfd,
3060 link_order->u.reloc.p->u.section)
3061 : link_order->u.reloc.p->u.name),
3062 howto->name, link_order->u.reloc.p->addend,
3063 (bfd *) NULL, (asection *) NULL, (bfd_vma) 0)))
3064 {
3065 free (buf);
3066 return false;
3067 }
3068 break;
3069 }
3070 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
3071 (file_ptr) link_order->offset, size);
3072 free (buf);
3073 if (! ok)
3074 return false;
3075 }
3076
3077 /* Figure out the symbol index. */
3078 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
3079 + output_section->reloc_count);
3080 if (link_order->type == bfd_section_reloc_link_order)
3081 {
3082 indx = link_order->u.reloc.p->u.section->target_index;
3083 BFD_ASSERT (indx != 0);
3084 *rel_hash_ptr = NULL;
3085 }
3086 else
3087 {
3088 struct elf_link_hash_entry *h;
3089
3090 h = elf_link_hash_lookup (elf_hash_table (info),
3091 link_order->u.reloc.p->u.name,
3092 false, false, true);
3093 if (h != NULL)
3094 {
3095 /* Setting the index to -2 tells elf_link_output_extsym that
3096 this symbol is used by a reloc. */
3097 h->indx = -2;
3098 *rel_hash_ptr = h;
3099 indx = 0;
3100 }
3101 else
3102 {
3103 if (! ((*info->callbacks->unattached_reloc)
3104 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
3105 (asection *) NULL, (bfd_vma) 0)))
3106 return false;
3107 indx = 0;
3108 }
3109 }
3110
3111 /* The address of a reloc is relative to the section in a
3112 relocateable file, and is a virtual address in an executable
3113 file. */
3114 offset = link_order->offset;
3115 if (! info->relocateable)
3116 offset += output_section->vma;
3117
3118 rel_hdr = &elf_section_data (output_section)->rel_hdr;
3119
3120 if (rel_hdr->sh_type == SHT_REL)
3121 {
3122 Elf_Internal_Rel irel;
3123 Elf_External_Rel *erel;
3124
3125 irel.r_offset = offset;
3126 irel.r_info = ELF_R_INFO (indx, howto->type);
3127 erel = ((Elf_External_Rel *) rel_hdr->contents
3128 + output_section->reloc_count);
3129 elf_swap_reloc_out (output_bfd, &irel, erel);
3130 }
3131 else
3132 {
3133 Elf_Internal_Rela irela;
3134 Elf_External_Rela *erela;
3135
3136 irela.r_offset = offset;
3137 irela.r_info = ELF_R_INFO (indx, howto->type);
3138 irela.r_addend = link_order->u.reloc.p->addend;
3139 erela = ((Elf_External_Rela *) rel_hdr->contents
3140 + output_section->reloc_count);
3141 elf_swap_reloca_out (output_bfd, &irela, erela);
3142 }
3143
3144 ++output_section->reloc_count;
3145
3146 return true;
3147 }
3148
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