1999-08-09 Geoff Keating <geoffk@cygnus.com>
[deliverable/binutils-gdb.git] / bfd / elflink.h
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999 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 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
24
25 struct elf_info_failed
26 {
27 boolean failed;
28 struct bfd_link_info *info;
29 };
30
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
62
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
65
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
70 {
71 switch (bfd_get_format (abfd))
72 {
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
80 }
81 }
82 \f
83
84 /* Add symbols from an ELF archive file to the linker hash table. We
85 don't use _bfd_generic_link_add_archive_symbols because of a
86 problem which arises on UnixWare. The UnixWare libc.so is an
87 archive which includes an entry libc.so.1 which defines a bunch of
88 symbols. The libc.so archive also includes a number of other
89 object files, which also define symbols, some of which are the same
90 as those defined in libc.so.1. Correct linking requires that we
91 consider each object file in turn, and include it if it defines any
92 symbols we need. _bfd_generic_link_add_archive_symbols does not do
93 this; it looks through the list of undefined symbols, and includes
94 any object file which defines them. When this algorithm is used on
95 UnixWare, it winds up pulling in libc.so.1 early and defining a
96 bunch of symbols. This means that some of the other objects in the
97 archive are not included in the link, which is incorrect since they
98 precede libc.so.1 in the archive.
99
100 Fortunately, ELF archive handling is simpler than that done by
101 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
102 oddities. In ELF, if we find a symbol in the archive map, and the
103 symbol is currently undefined, we know that we must pull in that
104 object file.
105
106 Unfortunately, we do have to make multiple passes over the symbol
107 table until nothing further is resolved. */
108
109 static boolean
110 elf_link_add_archive_symbols (abfd, info)
111 bfd *abfd;
112 struct bfd_link_info *info;
113 {
114 symindex c;
115 boolean *defined = NULL;
116 boolean *included = NULL;
117 carsym *symdefs;
118 boolean loop;
119
120 if (! bfd_has_map (abfd))
121 {
122 /* An empty archive is a special case. */
123 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
124 return true;
125 bfd_set_error (bfd_error_no_armap);
126 return false;
127 }
128
129 /* Keep track of all symbols we know to be already defined, and all
130 files we know to be already included. This is to speed up the
131 second and subsequent passes. */
132 c = bfd_ardata (abfd)->symdef_count;
133 if (c == 0)
134 return true;
135 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
136 included = (boolean *) bfd_malloc (c * sizeof (boolean));
137 if (defined == (boolean *) NULL || included == (boolean *) NULL)
138 goto error_return;
139 memset (defined, 0, c * sizeof (boolean));
140 memset (included, 0, c * sizeof (boolean));
141
142 symdefs = bfd_ardata (abfd)->symdefs;
143
144 do
145 {
146 file_ptr last;
147 symindex i;
148 carsym *symdef;
149 carsym *symdefend;
150
151 loop = false;
152 last = -1;
153
154 symdef = symdefs;
155 symdefend = symdef + c;
156 for (i = 0; symdef < symdefend; symdef++, i++)
157 {
158 struct elf_link_hash_entry *h;
159 bfd *element;
160 struct bfd_link_hash_entry *undefs_tail;
161 symindex mark;
162
163 if (defined[i] || included[i])
164 continue;
165 if (symdef->file_offset == last)
166 {
167 included[i] = true;
168 continue;
169 }
170
171 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
172 false, false, false);
173
174 if (h == NULL)
175 {
176 char *p, *copy;
177
178 /* If this is a default version (the name contains @@),
179 look up the symbol again without the version. The
180 effect is that references to the symbol without the
181 version will be matched by the default symbol in the
182 archive. */
183
184 p = strchr (symdef->name, ELF_VER_CHR);
185 if (p == NULL || p[1] != ELF_VER_CHR)
186 continue;
187
188 copy = bfd_alloc (abfd, p - symdef->name + 1);
189 if (copy == NULL)
190 goto error_return;
191 memcpy (copy, symdef->name, p - symdef->name);
192 copy[p - symdef->name] = '\0';
193
194 h = elf_link_hash_lookup (elf_hash_table (info), copy,
195 false, false, false);
196
197 bfd_release (abfd, copy);
198 }
199
200 if (h == NULL)
201 continue;
202
203 if (h->root.type != bfd_link_hash_undefined)
204 {
205 if (h->root.type != bfd_link_hash_undefweak)
206 defined[i] = true;
207 continue;
208 }
209
210 /* We need to include this archive member. */
211
212 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
213 if (element == (bfd *) NULL)
214 goto error_return;
215
216 if (! bfd_check_format (element, bfd_object))
217 goto error_return;
218
219 /* Doublecheck that we have not included this object
220 already--it should be impossible, but there may be
221 something wrong with the archive. */
222 if (element->archive_pass != 0)
223 {
224 bfd_set_error (bfd_error_bad_value);
225 goto error_return;
226 }
227 element->archive_pass = 1;
228
229 undefs_tail = info->hash->undefs_tail;
230
231 if (! (*info->callbacks->add_archive_element) (info, element,
232 symdef->name))
233 goto error_return;
234 if (! elf_link_add_object_symbols (element, info))
235 goto error_return;
236
237 /* If there are any new undefined symbols, we need to make
238 another pass through the archive in order to see whether
239 they can be defined. FIXME: This isn't perfect, because
240 common symbols wind up on undefs_tail and because an
241 undefined symbol which is defined later on in this pass
242 does not require another pass. This isn't a bug, but it
243 does make the code less efficient than it could be. */
244 if (undefs_tail != info->hash->undefs_tail)
245 loop = true;
246
247 /* Look backward to mark all symbols from this object file
248 which we have already seen in this pass. */
249 mark = i;
250 do
251 {
252 included[mark] = true;
253 if (mark == 0)
254 break;
255 --mark;
256 }
257 while (symdefs[mark].file_offset == symdef->file_offset);
258
259 /* We mark subsequent symbols from this object file as we go
260 on through the loop. */
261 last = symdef->file_offset;
262 }
263 }
264 while (loop);
265
266 free (defined);
267 free (included);
268
269 return true;
270
271 error_return:
272 if (defined != (boolean *) NULL)
273 free (defined);
274 if (included != (boolean *) NULL)
275 free (included);
276 return false;
277 }
278
279 /* This function is called when we want to define a new symbol. It
280 handles the various cases which arise when we find a definition in
281 a dynamic object, or when there is already a definition in a
282 dynamic object. The new symbol is described by NAME, SYM, PSEC,
283 and PVALUE. We set SYM_HASH to the hash table entry. We set
284 OVERRIDE if the old symbol is overriding a new definition. We set
285 TYPE_CHANGE_OK if it is OK for the type to change. We set
286 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
287 change, we mean that we shouldn't warn if the type or size does
288 change. */
289
290 static boolean
291 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
292 override, type_change_ok, size_change_ok)
293 bfd *abfd;
294 struct bfd_link_info *info;
295 const char *name;
296 Elf_Internal_Sym *sym;
297 asection **psec;
298 bfd_vma *pvalue;
299 struct elf_link_hash_entry **sym_hash;
300 boolean *override;
301 boolean *type_change_ok;
302 boolean *size_change_ok;
303 {
304 asection *sec;
305 struct elf_link_hash_entry *h;
306 int bind;
307 bfd *oldbfd;
308 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
309
310 *override = false;
311
312 sec = *psec;
313 bind = ELF_ST_BIND (sym->st_info);
314
315 if (! bfd_is_und_section (sec))
316 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
317 else
318 h = ((struct elf_link_hash_entry *)
319 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
320 if (h == NULL)
321 return false;
322 *sym_hash = h;
323
324 /* This code is for coping with dynamic objects, and is only useful
325 if we are doing an ELF link. */
326 if (info->hash->creator != abfd->xvec)
327 return true;
328
329 /* For merging, we only care about real symbols. */
330
331 while (h->root.type == bfd_link_hash_indirect
332 || h->root.type == bfd_link_hash_warning)
333 h = (struct elf_link_hash_entry *) h->root.u.i.link;
334
335 /* If we just created the symbol, mark it as being an ELF symbol.
336 Other than that, there is nothing to do--there is no merge issue
337 with a newly defined symbol--so we just return. */
338
339 if (h->root.type == bfd_link_hash_new)
340 {
341 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
342 return true;
343 }
344
345 /* OLDBFD is a BFD associated with the existing symbol. */
346
347 switch (h->root.type)
348 {
349 default:
350 oldbfd = NULL;
351 break;
352
353 case bfd_link_hash_undefined:
354 case bfd_link_hash_undefweak:
355 oldbfd = h->root.u.undef.abfd;
356 break;
357
358 case bfd_link_hash_defined:
359 case bfd_link_hash_defweak:
360 oldbfd = h->root.u.def.section->owner;
361 break;
362
363 case bfd_link_hash_common:
364 oldbfd = h->root.u.c.p->section->owner;
365 break;
366 }
367
368 /* In cases involving weak versioned symbols, we may wind up trying
369 to merge a symbol with itself. Catch that here, to avoid the
370 confusion that results if we try to override a symbol with
371 itself. The additional tests catch cases like
372 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
373 dynamic object, which we do want to handle here. */
374 if (abfd == oldbfd
375 && ((abfd->flags & DYNAMIC) == 0
376 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
377 return true;
378
379 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
380 respectively, is from a dynamic object. */
381
382 if ((abfd->flags & DYNAMIC) != 0)
383 newdyn = true;
384 else
385 newdyn = false;
386
387 if (oldbfd == NULL || (oldbfd->flags & DYNAMIC) == 0)
388 olddyn = false;
389 else
390 olddyn = true;
391
392 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
393 respectively, appear to be a definition rather than reference. */
394
395 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
396 newdef = false;
397 else
398 newdef = true;
399
400 if (h->root.type == bfd_link_hash_undefined
401 || h->root.type == bfd_link_hash_undefweak
402 || h->root.type == bfd_link_hash_common)
403 olddef = false;
404 else
405 olddef = true;
406
407 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
408 symbol, respectively, appears to be a common symbol in a dynamic
409 object. If a symbol appears in an uninitialized section, and is
410 not weak, and is not a function, then it may be a common symbol
411 which was resolved when the dynamic object was created. We want
412 to treat such symbols specially, because they raise special
413 considerations when setting the symbol size: if the symbol
414 appears as a common symbol in a regular object, and the size in
415 the regular object is larger, we must make sure that we use the
416 larger size. This problematic case can always be avoided in C,
417 but it must be handled correctly when using Fortran shared
418 libraries.
419
420 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
421 likewise for OLDDYNCOMMON and OLDDEF.
422
423 Note that this test is just a heuristic, and that it is quite
424 possible to have an uninitialized symbol in a shared object which
425 is really a definition, rather than a common symbol. This could
426 lead to some minor confusion when the symbol really is a common
427 symbol in some regular object. However, I think it will be
428 harmless. */
429
430 if (newdyn
431 && newdef
432 && (sec->flags & SEC_ALLOC) != 0
433 && (sec->flags & SEC_LOAD) == 0
434 && sym->st_size > 0
435 && bind != STB_WEAK
436 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
437 newdyncommon = true;
438 else
439 newdyncommon = false;
440
441 if (olddyn
442 && olddef
443 && h->root.type == bfd_link_hash_defined
444 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
445 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
446 && (h->root.u.def.section->flags & SEC_LOAD) == 0
447 && h->size > 0
448 && h->type != STT_FUNC)
449 olddyncommon = true;
450 else
451 olddyncommon = false;
452
453 /* It's OK to change the type if either the existing symbol or the
454 new symbol is weak. */
455
456 if (h->root.type == bfd_link_hash_defweak
457 || h->root.type == bfd_link_hash_undefweak
458 || bind == STB_WEAK)
459 *type_change_ok = true;
460
461 /* It's OK to change the size if either the existing symbol or the
462 new symbol is weak, or if the old symbol is undefined. */
463
464 if (*type_change_ok
465 || h->root.type == bfd_link_hash_undefined)
466 *size_change_ok = true;
467
468 /* If both the old and the new symbols look like common symbols in a
469 dynamic object, set the size of the symbol to the larger of the
470 two. */
471
472 if (olddyncommon
473 && newdyncommon
474 && sym->st_size != h->size)
475 {
476 /* Since we think we have two common symbols, issue a multiple
477 common warning if desired. Note that we only warn if the
478 size is different. If the size is the same, we simply let
479 the old symbol override the new one as normally happens with
480 symbols defined in dynamic objects. */
481
482 if (! ((*info->callbacks->multiple_common)
483 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
484 h->size, abfd, bfd_link_hash_common, sym->st_size)))
485 return false;
486
487 if (sym->st_size > h->size)
488 h->size = sym->st_size;
489
490 *size_change_ok = true;
491 }
492
493 /* If we are looking at a dynamic object, and we have found a
494 definition, we need to see if the symbol was already defined by
495 some other object. If so, we want to use the existing
496 definition, and we do not want to report a multiple symbol
497 definition error; we do this by clobbering *PSEC to be
498 bfd_und_section_ptr.
499
500 We treat a common symbol as a definition if the symbol in the
501 shared library is a function, since common symbols always
502 represent variables; this can cause confusion in principle, but
503 any such confusion would seem to indicate an erroneous program or
504 shared library. We also permit a common symbol in a regular
505 object to override a weak symbol in a shared object.
506
507 We prefer a non-weak definition in a shared library to a weak
508 definition in the executable. */
509
510 if (newdyn
511 && newdef
512 && (olddef
513 || (h->root.type == bfd_link_hash_common
514 && (bind == STB_WEAK
515 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
516 && (h->root.type != bfd_link_hash_defweak
517 || bind == STB_WEAK))
518 {
519 *override = true;
520 newdef = false;
521 newdyncommon = false;
522
523 *psec = sec = bfd_und_section_ptr;
524 *size_change_ok = true;
525
526 /* If we get here when the old symbol is a common symbol, then
527 we are explicitly letting it override a weak symbol or
528 function in a dynamic object, and we don't want to warn about
529 a type change. If the old symbol is a defined symbol, a type
530 change warning may still be appropriate. */
531
532 if (h->root.type == bfd_link_hash_common)
533 *type_change_ok = true;
534 }
535
536 /* Handle the special case of an old common symbol merging with a
537 new symbol which looks like a common symbol in a shared object.
538 We change *PSEC and *PVALUE to make the new symbol look like a
539 common symbol, and let _bfd_generic_link_add_one_symbol will do
540 the right thing. */
541
542 if (newdyncommon
543 && h->root.type == bfd_link_hash_common)
544 {
545 *override = true;
546 newdef = false;
547 newdyncommon = false;
548 *pvalue = sym->st_size;
549 *psec = sec = bfd_com_section_ptr;
550 *size_change_ok = true;
551 }
552
553 /* If the old symbol is from a dynamic object, and the new symbol is
554 a definition which is not from a dynamic object, then the new
555 symbol overrides the old symbol. Symbols from regular files
556 always take precedence over symbols from dynamic objects, even if
557 they are defined after the dynamic object in the link.
558
559 As above, we again permit a common symbol in a regular object to
560 override a definition in a shared object if the shared object
561 symbol is a function or is weak.
562
563 As above, we permit a non-weak definition in a shared object to
564 override a weak definition in a regular object. */
565
566 if (! newdyn
567 && (newdef
568 || (bfd_is_com_section (sec)
569 && (h->root.type == bfd_link_hash_defweak
570 || h->type == STT_FUNC)))
571 && olddyn
572 && olddef
573 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
574 && (bind != STB_WEAK
575 || h->root.type == bfd_link_hash_defweak))
576 {
577 /* Change the hash table entry to undefined, and let
578 _bfd_generic_link_add_one_symbol do the right thing with the
579 new definition. */
580
581 h->root.type = bfd_link_hash_undefined;
582 h->root.u.undef.abfd = h->root.u.def.section->owner;
583 *size_change_ok = true;
584
585 olddef = false;
586 olddyncommon = false;
587
588 /* We again permit a type change when a common symbol may be
589 overriding a function. */
590
591 if (bfd_is_com_section (sec))
592 *type_change_ok = true;
593
594 /* This union may have been set to be non-NULL when this symbol
595 was seen in a dynamic object. We must force the union to be
596 NULL, so that it is correct for a regular symbol. */
597
598 h->verinfo.vertree = NULL;
599
600 /* In this special case, if H is the target of an indirection,
601 we want the caller to frob with H rather than with the
602 indirect symbol. That will permit the caller to redefine the
603 target of the indirection, rather than the indirect symbol
604 itself. FIXME: This will break the -y option if we store a
605 symbol with a different name. */
606 *sym_hash = h;
607 }
608
609 /* Handle the special case of a new common symbol merging with an
610 old symbol that looks like it might be a common symbol defined in
611 a shared object. Note that we have already handled the case in
612 which a new common symbol should simply override the definition
613 in the shared library. */
614
615 if (! newdyn
616 && bfd_is_com_section (sec)
617 && olddyncommon)
618 {
619 /* It would be best if we could set the hash table entry to a
620 common symbol, but we don't know what to use for the section
621 or the alignment. */
622 if (! ((*info->callbacks->multiple_common)
623 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
624 h->size, abfd, bfd_link_hash_common, sym->st_size)))
625 return false;
626
627 /* If the predumed common symbol in the dynamic object is
628 larger, pretend that the new symbol has its size. */
629
630 if (h->size > *pvalue)
631 *pvalue = h->size;
632
633 /* FIXME: We no longer know the alignment required by the symbol
634 in the dynamic object, so we just wind up using the one from
635 the regular object. */
636
637 olddef = false;
638 olddyncommon = false;
639
640 h->root.type = bfd_link_hash_undefined;
641 h->root.u.undef.abfd = h->root.u.def.section->owner;
642
643 *size_change_ok = true;
644 *type_change_ok = true;
645
646 h->verinfo.vertree = NULL;
647 }
648
649 /* Handle the special case of a weak definition in a regular object
650 followed by a non-weak definition in a shared object. In this
651 case, we prefer the definition in the shared object. */
652 if (olddef
653 && h->root.type == bfd_link_hash_defweak
654 && newdef
655 && newdyn
656 && bind != STB_WEAK)
657 {
658 /* To make this work we have to frob the flags so that the rest
659 of the code does not think we are using the regular
660 definition. */
661 h->elf_link_hash_flags &= ~ ELF_LINK_HASH_DEF_REGULAR;
662 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
663
664 /* If H is the target of an indirection, we want the caller to
665 use H rather than the indirect symbol. Otherwise if we are
666 defining a new indirect symbol we will wind up attaching it
667 to the entry we are overriding. */
668 *sym_hash = h;
669 }
670
671 /* Handle the special case of a non-weak definition in a shared
672 object followed by a weak definition in a regular object. In
673 this case we prefer to definition in the shared object. To make
674 this work we have to tell the caller to not treat the new symbol
675 as a definition. */
676 if (olddef
677 && olddyn
678 && h->root.type != bfd_link_hash_defweak
679 && newdef
680 && ! newdyn
681 && bind == STB_WEAK)
682 *override = true;
683
684 return true;
685 }
686
687 /* Add symbols from an ELF object file to the linker hash table. */
688
689 static boolean
690 elf_link_add_object_symbols (abfd, info)
691 bfd *abfd;
692 struct bfd_link_info *info;
693 {
694 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
695 const Elf_Internal_Sym *,
696 const char **, flagword *,
697 asection **, bfd_vma *));
698 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
699 asection *, const Elf_Internal_Rela *));
700 boolean collect;
701 Elf_Internal_Shdr *hdr;
702 size_t symcount;
703 size_t extsymcount;
704 size_t extsymoff;
705 Elf_External_Sym *buf = NULL;
706 struct elf_link_hash_entry **sym_hash;
707 boolean dynamic;
708 bfd_byte *dynver = NULL;
709 Elf_External_Versym *extversym = NULL;
710 Elf_External_Versym *ever;
711 Elf_External_Dyn *dynbuf = NULL;
712 struct elf_link_hash_entry *weaks;
713 Elf_External_Sym *esym;
714 Elf_External_Sym *esymend;
715
716 add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook;
717 collect = get_elf_backend_data (abfd)->collect;
718
719 if ((abfd->flags & DYNAMIC) == 0)
720 dynamic = false;
721 else
722 {
723 dynamic = true;
724
725 /* You can't use -r against a dynamic object. Also, there's no
726 hope of using a dynamic object which does not exactly match
727 the format of the output file. */
728 if (info->relocateable || info->hash->creator != abfd->xvec)
729 {
730 bfd_set_error (bfd_error_invalid_operation);
731 goto error_return;
732 }
733 }
734
735 /* As a GNU extension, any input sections which are named
736 .gnu.warning.SYMBOL are treated as warning symbols for the given
737 symbol. This differs from .gnu.warning sections, which generate
738 warnings when they are included in an output file. */
739 if (! info->shared)
740 {
741 asection *s;
742
743 for (s = abfd->sections; s != NULL; s = s->next)
744 {
745 const char *name;
746
747 name = bfd_get_section_name (abfd, s);
748 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
749 {
750 char *msg;
751 bfd_size_type sz;
752
753 name += sizeof ".gnu.warning." - 1;
754
755 /* If this is a shared object, then look up the symbol
756 in the hash table. If it is there, and it is already
757 been defined, then we will not be using the entry
758 from this shared object, so we don't need to warn.
759 FIXME: If we see the definition in a regular object
760 later on, we will warn, but we shouldn't. The only
761 fix is to keep track of what warnings we are supposed
762 to emit, and then handle them all at the end of the
763 link. */
764 if (dynamic && abfd->xvec == info->hash->creator)
765 {
766 struct elf_link_hash_entry *h;
767
768 h = elf_link_hash_lookup (elf_hash_table (info), name,
769 false, false, true);
770
771 /* FIXME: What about bfd_link_hash_common? */
772 if (h != NULL
773 && (h->root.type == bfd_link_hash_defined
774 || h->root.type == bfd_link_hash_defweak))
775 {
776 /* We don't want to issue this warning. Clobber
777 the section size so that the warning does not
778 get copied into the output file. */
779 s->_raw_size = 0;
780 continue;
781 }
782 }
783
784 sz = bfd_section_size (abfd, s);
785 msg = (char *) bfd_alloc (abfd, sz + 1);
786 if (msg == NULL)
787 goto error_return;
788
789 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
790 goto error_return;
791
792 msg[sz] = '\0';
793
794 if (! (_bfd_generic_link_add_one_symbol
795 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
796 false, collect, (struct bfd_link_hash_entry **) NULL)))
797 goto error_return;
798
799 if (! info->relocateable)
800 {
801 /* Clobber the section size so that the warning does
802 not get copied into the output file. */
803 s->_raw_size = 0;
804 }
805 }
806 }
807 }
808
809 /* If this is a dynamic object, we always link against the .dynsym
810 symbol table, not the .symtab symbol table. The dynamic linker
811 will only see the .dynsym symbol table, so there is no reason to
812 look at .symtab for a dynamic object. */
813
814 if (! dynamic || elf_dynsymtab (abfd) == 0)
815 hdr = &elf_tdata (abfd)->symtab_hdr;
816 else
817 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
818
819 if (dynamic)
820 {
821 /* Read in any version definitions. */
822
823 if (! _bfd_elf_slurp_version_tables (abfd))
824 goto error_return;
825
826 /* Read in the symbol versions, but don't bother to convert them
827 to internal format. */
828 if (elf_dynversym (abfd) != 0)
829 {
830 Elf_Internal_Shdr *versymhdr;
831
832 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
833 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
834 if (extversym == NULL)
835 goto error_return;
836 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
837 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
838 != versymhdr->sh_size))
839 goto error_return;
840 }
841 }
842
843 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
844
845 /* The sh_info field of the symtab header tells us where the
846 external symbols start. We don't care about the local symbols at
847 this point. */
848 if (elf_bad_symtab (abfd))
849 {
850 extsymcount = symcount;
851 extsymoff = 0;
852 }
853 else
854 {
855 extsymcount = symcount - hdr->sh_info;
856 extsymoff = hdr->sh_info;
857 }
858
859 buf = ((Elf_External_Sym *)
860 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
861 if (buf == NULL && extsymcount != 0)
862 goto error_return;
863
864 /* We store a pointer to the hash table entry for each external
865 symbol. */
866 sym_hash = ((struct elf_link_hash_entry **)
867 bfd_alloc (abfd,
868 extsymcount * sizeof (struct elf_link_hash_entry *)));
869 if (sym_hash == NULL)
870 goto error_return;
871 elf_sym_hashes (abfd) = sym_hash;
872
873 if (! dynamic)
874 {
875 /* If we are creating a shared library, create all the dynamic
876 sections immediately. We need to attach them to something,
877 so we attach them to this BFD, provided it is the right
878 format. FIXME: If there are no input BFD's of the same
879 format as the output, we can't make a shared library. */
880 if (info->shared
881 && ! elf_hash_table (info)->dynamic_sections_created
882 && abfd->xvec == info->hash->creator)
883 {
884 if (! elf_link_create_dynamic_sections (abfd, info))
885 goto error_return;
886 }
887 }
888 else
889 {
890 asection *s;
891 boolean add_needed;
892 const char *name;
893 bfd_size_type oldsize;
894 bfd_size_type strindex;
895
896 /* Find the name to use in a DT_NEEDED entry that refers to this
897 object. If the object has a DT_SONAME entry, we use it.
898 Otherwise, if the generic linker stuck something in
899 elf_dt_name, we use that. Otherwise, we just use the file
900 name. If the generic linker put a null string into
901 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
902 there is a DT_SONAME entry. */
903 add_needed = true;
904 name = bfd_get_filename (abfd);
905 if (elf_dt_name (abfd) != NULL)
906 {
907 name = elf_dt_name (abfd);
908 if (*name == '\0')
909 add_needed = false;
910 }
911 s = bfd_get_section_by_name (abfd, ".dynamic");
912 if (s != NULL)
913 {
914 Elf_External_Dyn *extdyn;
915 Elf_External_Dyn *extdynend;
916 int elfsec;
917 unsigned long link;
918
919 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
920 if (dynbuf == NULL)
921 goto error_return;
922
923 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
924 (file_ptr) 0, s->_raw_size))
925 goto error_return;
926
927 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
928 if (elfsec == -1)
929 goto error_return;
930 link = elf_elfsections (abfd)[elfsec]->sh_link;
931
932 extdyn = dynbuf;
933 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
934 for (; extdyn < extdynend; extdyn++)
935 {
936 Elf_Internal_Dyn dyn;
937
938 elf_swap_dyn_in (abfd, extdyn, &dyn);
939 if (dyn.d_tag == DT_SONAME)
940 {
941 name = bfd_elf_string_from_elf_section (abfd, link,
942 dyn.d_un.d_val);
943 if (name == NULL)
944 goto error_return;
945 }
946 if (dyn.d_tag == DT_NEEDED)
947 {
948 struct bfd_link_needed_list *n, **pn;
949 char *fnm, *anm;
950
951 n = ((struct bfd_link_needed_list *)
952 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
953 fnm = bfd_elf_string_from_elf_section (abfd, link,
954 dyn.d_un.d_val);
955 if (n == NULL || fnm == NULL)
956 goto error_return;
957 anm = bfd_alloc (abfd, strlen (fnm) + 1);
958 if (anm == NULL)
959 goto error_return;
960 strcpy (anm, fnm);
961 n->name = anm;
962 n->by = abfd;
963 n->next = NULL;
964 for (pn = &elf_hash_table (info)->needed;
965 *pn != NULL;
966 pn = &(*pn)->next)
967 ;
968 *pn = n;
969 }
970 }
971
972 free (dynbuf);
973 dynbuf = NULL;
974 }
975
976 /* We do not want to include any of the sections in a dynamic
977 object in the output file. We hack by simply clobbering the
978 list of sections in the BFD. This could be handled more
979 cleanly by, say, a new section flag; the existing
980 SEC_NEVER_LOAD flag is not the one we want, because that one
981 still implies that the section takes up space in the output
982 file. */
983 abfd->sections = NULL;
984 abfd->section_count = 0;
985
986 /* If this is the first dynamic object found in the link, create
987 the special sections required for dynamic linking. */
988 if (! elf_hash_table (info)->dynamic_sections_created)
989 {
990 if (! elf_link_create_dynamic_sections (abfd, info))
991 goto error_return;
992 }
993
994 if (add_needed)
995 {
996 /* Add a DT_NEEDED entry for this dynamic object. */
997 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
998 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
999 true, false);
1000 if (strindex == (bfd_size_type) -1)
1001 goto error_return;
1002
1003 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1004 {
1005 asection *sdyn;
1006 Elf_External_Dyn *dyncon, *dynconend;
1007
1008 /* The hash table size did not change, which means that
1009 the dynamic object name was already entered. If we
1010 have already included this dynamic object in the
1011 link, just ignore it. There is no reason to include
1012 a particular dynamic object more than once. */
1013 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1014 ".dynamic");
1015 BFD_ASSERT (sdyn != NULL);
1016
1017 dyncon = (Elf_External_Dyn *) sdyn->contents;
1018 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1019 sdyn->_raw_size);
1020 for (; dyncon < dynconend; dyncon++)
1021 {
1022 Elf_Internal_Dyn dyn;
1023
1024 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1025 &dyn);
1026 if (dyn.d_tag == DT_NEEDED
1027 && dyn.d_un.d_val == strindex)
1028 {
1029 if (buf != NULL)
1030 free (buf);
1031 if (extversym != NULL)
1032 free (extversym);
1033 return true;
1034 }
1035 }
1036 }
1037
1038 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1039 goto error_return;
1040 }
1041
1042 /* Save the SONAME, if there is one, because sometimes the
1043 linker emulation code will need to know it. */
1044 if (*name == '\0')
1045 name = bfd_get_filename (abfd);
1046 elf_dt_name (abfd) = name;
1047 }
1048
1049 if (bfd_seek (abfd,
1050 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1051 SEEK_SET) != 0
1052 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1053 != extsymcount * sizeof (Elf_External_Sym)))
1054 goto error_return;
1055
1056 weaks = NULL;
1057
1058 ever = extversym != NULL ? extversym + extsymoff : NULL;
1059 esymend = buf + extsymcount;
1060 for (esym = buf;
1061 esym < esymend;
1062 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1063 {
1064 Elf_Internal_Sym sym;
1065 int bind;
1066 bfd_vma value;
1067 asection *sec;
1068 flagword flags;
1069 const char *name;
1070 struct elf_link_hash_entry *h;
1071 boolean definition;
1072 boolean size_change_ok, type_change_ok;
1073 boolean new_weakdef;
1074 unsigned int old_alignment;
1075
1076 elf_swap_symbol_in (abfd, esym, &sym);
1077
1078 flags = BSF_NO_FLAGS;
1079 sec = NULL;
1080 value = sym.st_value;
1081 *sym_hash = NULL;
1082
1083 bind = ELF_ST_BIND (sym.st_info);
1084 if (bind == STB_LOCAL)
1085 {
1086 /* This should be impossible, since ELF requires that all
1087 global symbols follow all local symbols, and that sh_info
1088 point to the first global symbol. Unfortunatealy, Irix 5
1089 screws this up. */
1090 continue;
1091 }
1092 else if (bind == STB_GLOBAL)
1093 {
1094 if (sym.st_shndx != SHN_UNDEF
1095 && sym.st_shndx != SHN_COMMON)
1096 flags = BSF_GLOBAL;
1097 else
1098 flags = 0;
1099 }
1100 else if (bind == STB_WEAK)
1101 flags = BSF_WEAK;
1102 else
1103 {
1104 /* Leave it up to the processor backend. */
1105 }
1106
1107 if (sym.st_shndx == SHN_UNDEF)
1108 sec = bfd_und_section_ptr;
1109 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1110 {
1111 sec = section_from_elf_index (abfd, sym.st_shndx);
1112 if (sec == NULL)
1113 sec = bfd_abs_section_ptr;
1114 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1115 value -= sec->vma;
1116 }
1117 else if (sym.st_shndx == SHN_ABS)
1118 sec = bfd_abs_section_ptr;
1119 else if (sym.st_shndx == SHN_COMMON)
1120 {
1121 sec = bfd_com_section_ptr;
1122 /* What ELF calls the size we call the value. What ELF
1123 calls the value we call the alignment. */
1124 value = sym.st_size;
1125 }
1126 else
1127 {
1128 /* Leave it up to the processor backend. */
1129 }
1130
1131 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1132 if (name == (const char *) NULL)
1133 goto error_return;
1134
1135 if (add_symbol_hook)
1136 {
1137 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1138 &value))
1139 goto error_return;
1140
1141 /* The hook function sets the name to NULL if this symbol
1142 should be skipped for some reason. */
1143 if (name == (const char *) NULL)
1144 continue;
1145 }
1146
1147 /* Sanity check that all possibilities were handled. */
1148 if (sec == (asection *) NULL)
1149 {
1150 bfd_set_error (bfd_error_bad_value);
1151 goto error_return;
1152 }
1153
1154 if (bfd_is_und_section (sec)
1155 || bfd_is_com_section (sec))
1156 definition = false;
1157 else
1158 definition = true;
1159
1160 size_change_ok = false;
1161 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1162 old_alignment = 0;
1163 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1164 {
1165 Elf_Internal_Versym iver;
1166 unsigned int vernum = 0;
1167 boolean override;
1168
1169 if (ever != NULL)
1170 {
1171 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1172 vernum = iver.vs_vers & VERSYM_VERSION;
1173
1174 /* If this is a hidden symbol, or if it is not version
1175 1, we append the version name to the symbol name.
1176 However, we do not modify a non-hidden absolute
1177 symbol, because it might be the version symbol
1178 itself. FIXME: What if it isn't? */
1179 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1180 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1181 {
1182 const char *verstr;
1183 int namelen, newlen;
1184 char *newname, *p;
1185
1186 if (sym.st_shndx != SHN_UNDEF)
1187 {
1188 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1189 {
1190 (*_bfd_error_handler)
1191 (_("%s: %s: invalid version %u (max %d)"),
1192 bfd_get_filename (abfd), name, vernum,
1193 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1194 bfd_set_error (bfd_error_bad_value);
1195 goto error_return;
1196 }
1197 else if (vernum > 1)
1198 verstr =
1199 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1200 else
1201 verstr = "";
1202 }
1203 else
1204 {
1205 /* We cannot simply test for the number of
1206 entries in the VERNEED section since the
1207 numbers for the needed versions do not start
1208 at 0. */
1209 Elf_Internal_Verneed *t;
1210
1211 verstr = NULL;
1212 for (t = elf_tdata (abfd)->verref;
1213 t != NULL;
1214 t = t->vn_nextref)
1215 {
1216 Elf_Internal_Vernaux *a;
1217
1218 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1219 {
1220 if (a->vna_other == vernum)
1221 {
1222 verstr = a->vna_nodename;
1223 break;
1224 }
1225 }
1226 if (a != NULL)
1227 break;
1228 }
1229 if (verstr == NULL)
1230 {
1231 (*_bfd_error_handler)
1232 (_("%s: %s: invalid needed version %d"),
1233 bfd_get_filename (abfd), name, vernum);
1234 bfd_set_error (bfd_error_bad_value);
1235 goto error_return;
1236 }
1237 }
1238
1239 namelen = strlen (name);
1240 newlen = namelen + strlen (verstr) + 2;
1241 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1242 ++newlen;
1243
1244 newname = (char *) bfd_alloc (abfd, newlen);
1245 if (newname == NULL)
1246 goto error_return;
1247 strcpy (newname, name);
1248 p = newname + namelen;
1249 *p++ = ELF_VER_CHR;
1250 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1251 *p++ = ELF_VER_CHR;
1252 strcpy (p, verstr);
1253
1254 name = newname;
1255 }
1256 }
1257
1258 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1259 sym_hash, &override, &type_change_ok,
1260 &size_change_ok))
1261 goto error_return;
1262
1263 if (override)
1264 definition = false;
1265
1266 h = *sym_hash;
1267 while (h->root.type == bfd_link_hash_indirect
1268 || h->root.type == bfd_link_hash_warning)
1269 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1270
1271 /* Remember the old alignment if this is a common symbol, so
1272 that we don't reduce the alignment later on. We can't
1273 check later, because _bfd_generic_link_add_one_symbol
1274 will set a default for the alignment which we want to
1275 override. */
1276 if (h->root.type == bfd_link_hash_common)
1277 old_alignment = h->root.u.c.p->alignment_power;
1278
1279 if (elf_tdata (abfd)->verdef != NULL
1280 && ! override
1281 && vernum > 1
1282 && definition)
1283 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1284 }
1285
1286 if (! (_bfd_generic_link_add_one_symbol
1287 (info, abfd, name, flags, sec, value, (const char *) NULL,
1288 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1289 goto error_return;
1290
1291 h = *sym_hash;
1292 while (h->root.type == bfd_link_hash_indirect
1293 || h->root.type == bfd_link_hash_warning)
1294 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1295 *sym_hash = h;
1296
1297 new_weakdef = false;
1298 if (dynamic
1299 && definition
1300 && (flags & BSF_WEAK) != 0
1301 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1302 && info->hash->creator->flavour == bfd_target_elf_flavour
1303 && h->weakdef == NULL)
1304 {
1305 /* Keep a list of all weak defined non function symbols from
1306 a dynamic object, using the weakdef field. Later in this
1307 function we will set the weakdef field to the correct
1308 value. We only put non-function symbols from dynamic
1309 objects on this list, because that happens to be the only
1310 time we need to know the normal symbol corresponding to a
1311 weak symbol, and the information is time consuming to
1312 figure out. If the weakdef field is not already NULL,
1313 then this symbol was already defined by some previous
1314 dynamic object, and we will be using that previous
1315 definition anyhow. */
1316
1317 h->weakdef = weaks;
1318 weaks = h;
1319 new_weakdef = true;
1320 }
1321
1322 /* Set the alignment of a common symbol. */
1323 if (sym.st_shndx == SHN_COMMON
1324 && h->root.type == bfd_link_hash_common)
1325 {
1326 unsigned int align;
1327
1328 align = bfd_log2 (sym.st_value);
1329 if (align > old_alignment)
1330 h->root.u.c.p->alignment_power = align;
1331 }
1332
1333 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1334 {
1335 int old_flags;
1336 boolean dynsym;
1337 int new_flag;
1338
1339 /* Remember the symbol size and type. */
1340 if (sym.st_size != 0
1341 && (definition || h->size == 0))
1342 {
1343 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1344 (*_bfd_error_handler)
1345 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1346 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1347 bfd_get_filename (abfd));
1348
1349 h->size = sym.st_size;
1350 }
1351
1352 /* If this is a common symbol, then we always want H->SIZE
1353 to be the size of the common symbol. The code just above
1354 won't fix the size if a common symbol becomes larger. We
1355 don't warn about a size change here, because that is
1356 covered by --warn-common. */
1357 if (h->root.type == bfd_link_hash_common)
1358 h->size = h->root.u.c.size;
1359
1360 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1361 && (definition || h->type == STT_NOTYPE))
1362 {
1363 if (h->type != STT_NOTYPE
1364 && h->type != ELF_ST_TYPE (sym.st_info)
1365 && ! type_change_ok)
1366 (*_bfd_error_handler)
1367 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1368 name, h->type, ELF_ST_TYPE (sym.st_info),
1369 bfd_get_filename (abfd));
1370
1371 h->type = ELF_ST_TYPE (sym.st_info);
1372 }
1373
1374 if (sym.st_other != 0
1375 && (definition || h->other == 0))
1376 h->other = sym.st_other;
1377
1378 /* Set a flag in the hash table entry indicating the type of
1379 reference or definition we just found. Keep a count of
1380 the number of dynamic symbols we find. A dynamic symbol
1381 is one which is referenced or defined by both a regular
1382 object and a shared object. */
1383 old_flags = h->elf_link_hash_flags;
1384 dynsym = false;
1385 if (! dynamic)
1386 {
1387 if (! definition)
1388 {
1389 new_flag = ELF_LINK_HASH_REF_REGULAR;
1390 if (bind != STB_WEAK)
1391 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1392 }
1393 else
1394 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1395 if (info->shared
1396 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1397 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1398 dynsym = true;
1399 }
1400 else
1401 {
1402 if (! definition)
1403 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1404 else
1405 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1406 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1407 | ELF_LINK_HASH_REF_REGULAR)) != 0
1408 || (h->weakdef != NULL
1409 && ! new_weakdef
1410 && h->weakdef->dynindx != -1))
1411 dynsym = true;
1412 }
1413
1414 h->elf_link_hash_flags |= new_flag;
1415
1416 /* If this symbol has a version, and it is the default
1417 version, we create an indirect symbol from the default
1418 name to the fully decorated name. This will cause
1419 external references which do not specify a version to be
1420 bound to this version of the symbol. */
1421 if (definition)
1422 {
1423 char *p;
1424
1425 p = strchr (name, ELF_VER_CHR);
1426 if (p != NULL && p[1] == ELF_VER_CHR)
1427 {
1428 char *shortname;
1429 struct elf_link_hash_entry *hi;
1430 boolean override;
1431
1432 shortname = bfd_hash_allocate (&info->hash->table,
1433 p - name + 1);
1434 if (shortname == NULL)
1435 goto error_return;
1436 strncpy (shortname, name, p - name);
1437 shortname[p - name] = '\0';
1438
1439 /* We are going to create a new symbol. Merge it
1440 with any existing symbol with this name. For the
1441 purposes of the merge, act as though we were
1442 defining the symbol we just defined, although we
1443 actually going to define an indirect symbol. */
1444 type_change_ok = false;
1445 size_change_ok = false;
1446 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1447 &value, &hi, &override,
1448 &type_change_ok, &size_change_ok))
1449 goto error_return;
1450
1451 if (! override)
1452 {
1453 if (! (_bfd_generic_link_add_one_symbol
1454 (info, abfd, shortname, BSF_INDIRECT,
1455 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1456 collect, (struct bfd_link_hash_entry **) &hi)))
1457 goto error_return;
1458 }
1459 else
1460 {
1461 /* In this case the symbol named SHORTNAME is
1462 overriding the indirect symbol we want to
1463 add. We were planning on making SHORTNAME an
1464 indirect symbol referring to NAME. SHORTNAME
1465 is the name without a version. NAME is the
1466 fully versioned name, and it is the default
1467 version.
1468
1469 Overriding means that we already saw a
1470 definition for the symbol SHORTNAME in a
1471 regular object, and it is overriding the
1472 symbol defined in the dynamic object.
1473
1474 When this happens, we actually want to change
1475 NAME, the symbol we just added, to refer to
1476 SHORTNAME. This will cause references to
1477 NAME in the shared object to become
1478 references to SHORTNAME in the regular
1479 object. This is what we expect when we
1480 override a function in a shared object: that
1481 the references in the shared object will be
1482 mapped to the definition in the regular
1483 object. */
1484
1485 while (hi->root.type == bfd_link_hash_indirect
1486 || hi->root.type == bfd_link_hash_warning)
1487 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1488
1489 h->root.type = bfd_link_hash_indirect;
1490 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1491 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1492 {
1493 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1494 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1495 if (hi->elf_link_hash_flags
1496 & (ELF_LINK_HASH_REF_REGULAR
1497 | ELF_LINK_HASH_DEF_REGULAR))
1498 {
1499 if (! _bfd_elf_link_record_dynamic_symbol (info,
1500 hi))
1501 goto error_return;
1502 }
1503 }
1504
1505 /* Now set HI to H, so that the following code
1506 will set the other fields correctly. */
1507 hi = h;
1508 }
1509
1510 /* If there is a duplicate definition somewhere,
1511 then HI may not point to an indirect symbol. We
1512 will have reported an error to the user in that
1513 case. */
1514
1515 if (hi->root.type == bfd_link_hash_indirect)
1516 {
1517 struct elf_link_hash_entry *ht;
1518
1519 /* If the symbol became indirect, then we assume
1520 that we have not seen a definition before. */
1521 BFD_ASSERT ((hi->elf_link_hash_flags
1522 & (ELF_LINK_HASH_DEF_DYNAMIC
1523 | ELF_LINK_HASH_DEF_REGULAR))
1524 == 0);
1525
1526 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1527
1528 /* Copy down any references that we may have
1529 already seen to the symbol which just became
1530 indirect. */
1531 ht->elf_link_hash_flags |=
1532 (hi->elf_link_hash_flags
1533 & (ELF_LINK_HASH_REF_DYNAMIC
1534 | ELF_LINK_HASH_REF_REGULAR
1535 | ELF_LINK_HASH_REF_REGULAR_NONWEAK));
1536
1537 /* Copy over the global and procedure linkage table
1538 offset entries. These may have been already set
1539 up by a check_relocs routine. */
1540 if (ht->got.offset == (bfd_vma) -1)
1541 {
1542 ht->got.offset = hi->got.offset;
1543 hi->got.offset = (bfd_vma) -1;
1544 }
1545 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1546
1547 if (ht->plt.offset == (bfd_vma) -1)
1548 {
1549 ht->plt.offset = hi->plt.offset;
1550 hi->plt.offset = (bfd_vma) -1;
1551 }
1552 BFD_ASSERT (hi->plt.offset == (bfd_vma) -1);
1553
1554 if (ht->dynindx == -1)
1555 {
1556 ht->dynindx = hi->dynindx;
1557 ht->dynstr_index = hi->dynstr_index;
1558 hi->dynindx = -1;
1559 hi->dynstr_index = 0;
1560 }
1561 BFD_ASSERT (hi->dynindx == -1);
1562
1563 /* FIXME: There may be other information to copy
1564 over for particular targets. */
1565
1566 /* See if the new flags lead us to realize that
1567 the symbol must be dynamic. */
1568 if (! dynsym)
1569 {
1570 if (! dynamic)
1571 {
1572 if (info->shared
1573 || ((hi->elf_link_hash_flags
1574 & ELF_LINK_HASH_REF_DYNAMIC)
1575 != 0))
1576 dynsym = true;
1577 }
1578 else
1579 {
1580 if ((hi->elf_link_hash_flags
1581 & ELF_LINK_HASH_REF_REGULAR) != 0)
1582 dynsym = true;
1583 }
1584 }
1585 }
1586
1587 /* We also need to define an indirection from the
1588 nondefault version of the symbol. */
1589
1590 shortname = bfd_hash_allocate (&info->hash->table,
1591 strlen (name));
1592 if (shortname == NULL)
1593 goto error_return;
1594 strncpy (shortname, name, p - name);
1595 strcpy (shortname + (p - name), p + 1);
1596
1597 /* Once again, merge with any existing symbol. */
1598 type_change_ok = false;
1599 size_change_ok = false;
1600 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1601 &value, &hi, &override,
1602 &type_change_ok, &size_change_ok))
1603 goto error_return;
1604
1605 if (override)
1606 {
1607 /* Here SHORTNAME is a versioned name, so we
1608 don't expect to see the type of override we
1609 do in the case above. */
1610 (*_bfd_error_handler)
1611 (_("%s: warning: unexpected redefinition of `%s'"),
1612 bfd_get_filename (abfd), shortname);
1613 }
1614 else
1615 {
1616 if (! (_bfd_generic_link_add_one_symbol
1617 (info, abfd, shortname, BSF_INDIRECT,
1618 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1619 collect, (struct bfd_link_hash_entry **) &hi)))
1620 goto error_return;
1621
1622 /* If there is a duplicate definition somewhere,
1623 then HI may not point to an indirect symbol.
1624 We will have reported an error to the user in
1625 that case. */
1626
1627 if (hi->root.type == bfd_link_hash_indirect)
1628 {
1629 /* If the symbol became indirect, then we
1630 assume that we have not seen a definition
1631 before. */
1632 BFD_ASSERT ((hi->elf_link_hash_flags
1633 & (ELF_LINK_HASH_DEF_DYNAMIC
1634 | ELF_LINK_HASH_DEF_REGULAR))
1635 == 0);
1636
1637 /* Copy down any references that we may have
1638 already seen to the symbol which just
1639 became indirect. */
1640 h->elf_link_hash_flags |=
1641 (hi->elf_link_hash_flags
1642 & (ELF_LINK_HASH_REF_DYNAMIC
1643 | ELF_LINK_HASH_REF_REGULAR
1644 | ELF_LINK_HASH_REF_REGULAR_NONWEAK));
1645
1646 /* Copy over the global and procedure linkage
1647 table offset entries. These may have been
1648 already set up by a check_relocs routine. */
1649 if (h->got.offset == (bfd_vma) -1)
1650 {
1651 h->got.offset = hi->got.offset;
1652 hi->got.offset = (bfd_vma) -1;
1653 }
1654 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1655
1656 if (h->plt.offset == (bfd_vma) -1)
1657 {
1658 h->plt.offset = hi->plt.offset;
1659 hi->plt.offset = (bfd_vma) -1;
1660 }
1661 BFD_ASSERT (hi->got.offset == (bfd_vma) -1);
1662
1663 if (h->dynindx == -1)
1664 {
1665 h->dynindx = hi->dynindx;
1666 h->dynstr_index = hi->dynstr_index;
1667 hi->dynindx = -1;
1668 hi->dynstr_index = 0;
1669 }
1670 BFD_ASSERT (hi->dynindx == -1);
1671
1672 /* FIXME: There may be other information to
1673 copy over for particular targets. */
1674
1675 /* See if the new flags lead us to realize
1676 that the symbol must be dynamic. */
1677 if (! dynsym)
1678 {
1679 if (! dynamic)
1680 {
1681 if (info->shared
1682 || ((hi->elf_link_hash_flags
1683 & ELF_LINK_HASH_REF_DYNAMIC)
1684 != 0))
1685 dynsym = true;
1686 }
1687 else
1688 {
1689 if ((hi->elf_link_hash_flags
1690 & ELF_LINK_HASH_REF_REGULAR) != 0)
1691 dynsym = true;
1692 }
1693 }
1694 }
1695 }
1696 }
1697 }
1698
1699 if (dynsym && h->dynindx == -1)
1700 {
1701 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1702 goto error_return;
1703 if (h->weakdef != NULL
1704 && ! new_weakdef
1705 && h->weakdef->dynindx == -1)
1706 {
1707 if (! _bfd_elf_link_record_dynamic_symbol (info,
1708 h->weakdef))
1709 goto error_return;
1710 }
1711 }
1712 }
1713 }
1714
1715 /* Now set the weakdefs field correctly for all the weak defined
1716 symbols we found. The only way to do this is to search all the
1717 symbols. Since we only need the information for non functions in
1718 dynamic objects, that's the only time we actually put anything on
1719 the list WEAKS. We need this information so that if a regular
1720 object refers to a symbol defined weakly in a dynamic object, the
1721 real symbol in the dynamic object is also put in the dynamic
1722 symbols; we also must arrange for both symbols to point to the
1723 same memory location. We could handle the general case of symbol
1724 aliasing, but a general symbol alias can only be generated in
1725 assembler code, handling it correctly would be very time
1726 consuming, and other ELF linkers don't handle general aliasing
1727 either. */
1728 while (weaks != NULL)
1729 {
1730 struct elf_link_hash_entry *hlook;
1731 asection *slook;
1732 bfd_vma vlook;
1733 struct elf_link_hash_entry **hpp;
1734 struct elf_link_hash_entry **hppend;
1735
1736 hlook = weaks;
1737 weaks = hlook->weakdef;
1738 hlook->weakdef = NULL;
1739
1740 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
1741 || hlook->root.type == bfd_link_hash_defweak
1742 || hlook->root.type == bfd_link_hash_common
1743 || hlook->root.type == bfd_link_hash_indirect);
1744 slook = hlook->root.u.def.section;
1745 vlook = hlook->root.u.def.value;
1746
1747 hpp = elf_sym_hashes (abfd);
1748 hppend = hpp + extsymcount;
1749 for (; hpp < hppend; hpp++)
1750 {
1751 struct elf_link_hash_entry *h;
1752
1753 h = *hpp;
1754 if (h != NULL && h != hlook
1755 && h->root.type == bfd_link_hash_defined
1756 && h->root.u.def.section == slook
1757 && h->root.u.def.value == vlook)
1758 {
1759 hlook->weakdef = h;
1760
1761 /* If the weak definition is in the list of dynamic
1762 symbols, make sure the real definition is put there
1763 as well. */
1764 if (hlook->dynindx != -1
1765 && h->dynindx == -1)
1766 {
1767 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1768 goto error_return;
1769 }
1770
1771 /* If the real definition is in the list of dynamic
1772 symbols, make sure the weak definition is put there
1773 as well. If we don't do this, then the dynamic
1774 loader might not merge the entries for the real
1775 definition and the weak definition. */
1776 if (h->dynindx != -1
1777 && hlook->dynindx == -1)
1778 {
1779 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
1780 goto error_return;
1781 }
1782
1783 break;
1784 }
1785 }
1786 }
1787
1788 if (buf != NULL)
1789 {
1790 free (buf);
1791 buf = NULL;
1792 }
1793
1794 if (extversym != NULL)
1795 {
1796 free (extversym);
1797 extversym = NULL;
1798 }
1799
1800 /* If this object is the same format as the output object, and it is
1801 not a shared library, then let the backend look through the
1802 relocs.
1803
1804 This is required to build global offset table entries and to
1805 arrange for dynamic relocs. It is not required for the
1806 particular common case of linking non PIC code, even when linking
1807 against shared libraries, but unfortunately there is no way of
1808 knowing whether an object file has been compiled PIC or not.
1809 Looking through the relocs is not particularly time consuming.
1810 The problem is that we must either (1) keep the relocs in memory,
1811 which causes the linker to require additional runtime memory or
1812 (2) read the relocs twice from the input file, which wastes time.
1813 This would be a good case for using mmap.
1814
1815 I have no idea how to handle linking PIC code into a file of a
1816 different format. It probably can't be done. */
1817 check_relocs = get_elf_backend_data (abfd)->check_relocs;
1818 if (! dynamic
1819 && abfd->xvec == info->hash->creator
1820 && check_relocs != NULL)
1821 {
1822 asection *o;
1823
1824 for (o = abfd->sections; o != NULL; o = o->next)
1825 {
1826 Elf_Internal_Rela *internal_relocs;
1827 boolean ok;
1828
1829 if ((o->flags & SEC_RELOC) == 0
1830 || o->reloc_count == 0
1831 || ((info->strip == strip_all || info->strip == strip_debugger)
1832 && (o->flags & SEC_DEBUGGING) != 0)
1833 || bfd_is_abs_section (o->output_section))
1834 continue;
1835
1836 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
1837 (abfd, o, (PTR) NULL,
1838 (Elf_Internal_Rela *) NULL,
1839 info->keep_memory));
1840 if (internal_relocs == NULL)
1841 goto error_return;
1842
1843 ok = (*check_relocs) (abfd, info, o, internal_relocs);
1844
1845 if (! info->keep_memory)
1846 free (internal_relocs);
1847
1848 if (! ok)
1849 goto error_return;
1850 }
1851 }
1852
1853 /* If this is a non-traditional, non-relocateable link, try to
1854 optimize the handling of the .stab/.stabstr sections. */
1855 if (! dynamic
1856 && ! info->relocateable
1857 && ! info->traditional_format
1858 && info->hash->creator->flavour == bfd_target_elf_flavour
1859 && (info->strip != strip_all && info->strip != strip_debugger))
1860 {
1861 asection *stab, *stabstr;
1862
1863 stab = bfd_get_section_by_name (abfd, ".stab");
1864 if (stab != NULL)
1865 {
1866 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
1867
1868 if (stabstr != NULL)
1869 {
1870 struct bfd_elf_section_data *secdata;
1871
1872 secdata = elf_section_data (stab);
1873 if (! _bfd_link_section_stabs (abfd,
1874 &elf_hash_table (info)->stab_info,
1875 stab, stabstr,
1876 &secdata->stab_info))
1877 goto error_return;
1878 }
1879 }
1880 }
1881
1882 return true;
1883
1884 error_return:
1885 if (buf != NULL)
1886 free (buf);
1887 if (dynbuf != NULL)
1888 free (dynbuf);
1889 if (dynver != NULL)
1890 free (dynver);
1891 if (extversym != NULL)
1892 free (extversym);
1893 return false;
1894 }
1895
1896 /* Create some sections which will be filled in with dynamic linking
1897 information. ABFD is an input file which requires dynamic sections
1898 to be created. The dynamic sections take up virtual memory space
1899 when the final executable is run, so we need to create them before
1900 addresses are assigned to the output sections. We work out the
1901 actual contents and size of these sections later. */
1902
1903 boolean
1904 elf_link_create_dynamic_sections (abfd, info)
1905 bfd *abfd;
1906 struct bfd_link_info *info;
1907 {
1908 flagword flags;
1909 register asection *s;
1910 struct elf_link_hash_entry *h;
1911 struct elf_backend_data *bed;
1912
1913 if (elf_hash_table (info)->dynamic_sections_created)
1914 return true;
1915
1916 /* Make sure that all dynamic sections use the same input BFD. */
1917 if (elf_hash_table (info)->dynobj == NULL)
1918 elf_hash_table (info)->dynobj = abfd;
1919 else
1920 abfd = elf_hash_table (info)->dynobj;
1921
1922 /* Note that we set the SEC_IN_MEMORY flag for all of these
1923 sections. */
1924 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
1925 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1926
1927 /* A dynamically linked executable has a .interp section, but a
1928 shared library does not. */
1929 if (! info->shared)
1930 {
1931 s = bfd_make_section (abfd, ".interp");
1932 if (s == NULL
1933 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1934 return false;
1935 }
1936
1937 /* Create sections to hold version informations. These are removed
1938 if they are not needed. */
1939 s = bfd_make_section (abfd, ".gnu.version_d");
1940 if (s == NULL
1941 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1942 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1943 return false;
1944
1945 s = bfd_make_section (abfd, ".gnu.version");
1946 if (s == NULL
1947 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1948 || ! bfd_set_section_alignment (abfd, s, 1))
1949 return false;
1950
1951 s = bfd_make_section (abfd, ".gnu.version_r");
1952 if (s == NULL
1953 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1954 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1955 return false;
1956
1957 s = bfd_make_section (abfd, ".dynsym");
1958 if (s == NULL
1959 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
1960 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1961 return false;
1962
1963 s = bfd_make_section (abfd, ".dynstr");
1964 if (s == NULL
1965 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
1966 return false;
1967
1968 /* Create a strtab to hold the dynamic symbol names. */
1969 if (elf_hash_table (info)->dynstr == NULL)
1970 {
1971 elf_hash_table (info)->dynstr = elf_stringtab_init ();
1972 if (elf_hash_table (info)->dynstr == NULL)
1973 return false;
1974 }
1975
1976 s = bfd_make_section (abfd, ".dynamic");
1977 if (s == NULL
1978 || ! bfd_set_section_flags (abfd, s, flags)
1979 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
1980 return false;
1981
1982 /* The special symbol _DYNAMIC is always set to the start of the
1983 .dynamic section. This call occurs before we have processed the
1984 symbols for any dynamic object, so we don't have to worry about
1985 overriding a dynamic definition. We could set _DYNAMIC in a
1986 linker script, but we only want to define it if we are, in fact,
1987 creating a .dynamic section. We don't want to define it if there
1988 is no .dynamic section, since on some ELF platforms the start up
1989 code examines it to decide how to initialize the process. */
1990 h = NULL;
1991 if (! (_bfd_generic_link_add_one_symbol
1992 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
1993 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
1994 (struct bfd_link_hash_entry **) &h)))
1995 return false;
1996 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
1997 h->type = STT_OBJECT;
1998
1999 if (info->shared
2000 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2001 return false;
2002
2003 bed = get_elf_backend_data (abfd);
2004
2005 s = bfd_make_section (abfd, ".hash");
2006 if (s == NULL
2007 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2008 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2009 return false;
2010 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2011
2012 /* Let the backend create the rest of the sections. This lets the
2013 backend set the right flags. The backend will normally create
2014 the .got and .plt sections. */
2015 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2016 return false;
2017
2018 elf_hash_table (info)->dynamic_sections_created = true;
2019
2020 return true;
2021 }
2022
2023 /* Add an entry to the .dynamic table. */
2024
2025 boolean
2026 elf_add_dynamic_entry (info, tag, val)
2027 struct bfd_link_info *info;
2028 bfd_vma tag;
2029 bfd_vma val;
2030 {
2031 Elf_Internal_Dyn dyn;
2032 bfd *dynobj;
2033 asection *s;
2034 size_t newsize;
2035 bfd_byte *newcontents;
2036
2037 dynobj = elf_hash_table (info)->dynobj;
2038
2039 s = bfd_get_section_by_name (dynobj, ".dynamic");
2040 BFD_ASSERT (s != NULL);
2041
2042 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2043 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2044 if (newcontents == NULL)
2045 return false;
2046
2047 dyn.d_tag = tag;
2048 dyn.d_un.d_val = val;
2049 elf_swap_dyn_out (dynobj, &dyn,
2050 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2051
2052 s->_raw_size = newsize;
2053 s->contents = newcontents;
2054
2055 return true;
2056 }
2057
2058 /* Record a new local dynamic symbol. */
2059
2060 boolean
2061 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2062 struct bfd_link_info *info;
2063 bfd *input_bfd;
2064 long input_indx;
2065 {
2066 struct elf_link_local_dynamic_entry *entry;
2067 struct elf_link_hash_table *eht;
2068 struct bfd_strtab_hash *dynstr;
2069 Elf_External_Sym esym;
2070 unsigned long dynstr_index;
2071 char *name;
2072
2073 /* See if the entry exists already. */
2074 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2075 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2076 return true;
2077
2078 entry = (struct elf_link_local_dynamic_entry *)
2079 bfd_alloc (input_bfd, sizeof (*entry));
2080 if (entry == NULL)
2081 return false;
2082
2083 /* Go find the symbol, so that we can find it's name. */
2084 if (bfd_seek (input_bfd,
2085 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2086 + input_indx * sizeof (Elf_External_Sym)),
2087 SEEK_SET) != 0
2088 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2089 != sizeof (Elf_External_Sym)))
2090 return false;
2091 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2092
2093 name = (bfd_elf_string_from_elf_section
2094 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2095 entry->isym.st_name));
2096
2097 dynstr = elf_hash_table (info)->dynstr;
2098 if (dynstr == NULL)
2099 {
2100 /* Create a strtab to hold the dynamic symbol names. */
2101 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2102 if (dynstr == NULL)
2103 return false;
2104 }
2105
2106 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2107 if (dynstr_index == (unsigned long) -1)
2108 return false;
2109 entry->isym.st_name = dynstr_index;
2110
2111 eht = elf_hash_table (info);
2112
2113 entry->next = eht->dynlocal;
2114 eht->dynlocal = entry;
2115 entry->input_bfd = input_bfd;
2116 entry->input_indx = input_indx;
2117 eht->dynsymcount++;
2118
2119 /* Whatever binding the symbol had before, it's now local. */
2120 entry->isym.st_info
2121 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2122
2123 /* The dynindx will be set at the end of size_dynamic_sections. */
2124
2125 return true;
2126 }
2127 \f
2128
2129 /* Read and swap the relocs from the section indicated by SHDR. This
2130 may be either a REL or a RELA section. The relocations are
2131 translated into RELA relocations and stored in INTERNAL_RELOCS,
2132 which should have already been allocated to contain enough space.
2133 The EXTERNAL_RELOCS are a buffer where the external form of the
2134 relocations should be stored.
2135
2136 Returns false if something goes wrong. */
2137
2138 static boolean
2139 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2140 internal_relocs)
2141 bfd *abfd;
2142 Elf_Internal_Shdr *shdr;
2143 PTR external_relocs;
2144 Elf_Internal_Rela *internal_relocs;
2145 {
2146 struct elf_backend_data *bed;
2147
2148 /* If there aren't any relocations, that's OK. */
2149 if (!shdr)
2150 return true;
2151
2152 /* Position ourselves at the start of the section. */
2153 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2154 return false;
2155
2156 /* Read the relocations. */
2157 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2158 != shdr->sh_size)
2159 return false;
2160
2161 bed = get_elf_backend_data (abfd);
2162
2163 /* Convert the external relocations to the internal format. */
2164 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2165 {
2166 Elf_External_Rel *erel;
2167 Elf_External_Rel *erelend;
2168 Elf_Internal_Rela *irela;
2169 Elf_Internal_Rel *irel;
2170
2171 erel = (Elf_External_Rel *) external_relocs;
2172 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2173 irela = internal_relocs;
2174 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2175 * sizeof (Elf_Internal_Rel)));
2176 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2177 {
2178 unsigned char i;
2179
2180 if (bed->s->swap_reloc_in)
2181 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2182 else
2183 elf_swap_reloc_in (abfd, erel, irel);
2184
2185 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2186 {
2187 irela[i].r_offset = irel[i].r_offset;
2188 irela[i].r_info = irel[i].r_info;
2189 irela[i].r_addend = 0;
2190 }
2191 }
2192 }
2193 else
2194 {
2195 Elf_External_Rela *erela;
2196 Elf_External_Rela *erelaend;
2197 Elf_Internal_Rela *irela;
2198
2199 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2200
2201 erela = (Elf_External_Rela *) external_relocs;
2202 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2203 irela = internal_relocs;
2204 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2205 {
2206 if (bed->s->swap_reloca_in)
2207 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2208 else
2209 elf_swap_reloca_in (abfd, erela, irela);
2210 }
2211 }
2212
2213 return true;
2214 }
2215
2216 /* Read and swap the relocs for a section O. They may have been
2217 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2218 not NULL, they are used as buffers to read into. They are known to
2219 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2220 the return value is allocated using either malloc or bfd_alloc,
2221 according to the KEEP_MEMORY argument. If O has two relocation
2222 sections (both REL and RELA relocations), then the REL_HDR
2223 relocations will appear first in INTERNAL_RELOCS, followed by the
2224 REL_HDR2 relocations. */
2225
2226 Elf_Internal_Rela *
2227 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2228 keep_memory)
2229 bfd *abfd;
2230 asection *o;
2231 PTR external_relocs;
2232 Elf_Internal_Rela *internal_relocs;
2233 boolean keep_memory;
2234 {
2235 Elf_Internal_Shdr *rel_hdr;
2236 PTR alloc1 = NULL;
2237 Elf_Internal_Rela *alloc2 = NULL;
2238 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2239
2240 if (elf_section_data (o)->relocs != NULL)
2241 return elf_section_data (o)->relocs;
2242
2243 if (o->reloc_count == 0)
2244 return NULL;
2245
2246 rel_hdr = &elf_section_data (o)->rel_hdr;
2247
2248 if (internal_relocs == NULL)
2249 {
2250 size_t size;
2251
2252 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2253 * sizeof (Elf_Internal_Rela));
2254 if (keep_memory)
2255 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2256 else
2257 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2258 if (internal_relocs == NULL)
2259 goto error_return;
2260 }
2261
2262 if (external_relocs == NULL)
2263 {
2264 size_t size = (size_t) rel_hdr->sh_size;
2265
2266 if (elf_section_data (o)->rel_hdr2)
2267 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2268 alloc1 = (PTR) bfd_malloc (size);
2269 if (alloc1 == NULL)
2270 goto error_return;
2271 external_relocs = alloc1;
2272 }
2273
2274 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2275 external_relocs,
2276 internal_relocs))
2277 goto error_return;
2278 if (!elf_link_read_relocs_from_section
2279 (abfd,
2280 elf_section_data (o)->rel_hdr2,
2281 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2282 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2283 * bed->s->int_rels_per_ext_rel)))
2284 goto error_return;
2285
2286 /* Cache the results for next time, if we can. */
2287 if (keep_memory)
2288 elf_section_data (o)->relocs = internal_relocs;
2289
2290 if (alloc1 != NULL)
2291 free (alloc1);
2292
2293 /* Don't free alloc2, since if it was allocated we are passing it
2294 back (under the name of internal_relocs). */
2295
2296 return internal_relocs;
2297
2298 error_return:
2299 if (alloc1 != NULL)
2300 free (alloc1);
2301 if (alloc2 != NULL)
2302 free (alloc2);
2303 return NULL;
2304 }
2305 \f
2306
2307 /* Record an assignment to a symbol made by a linker script. We need
2308 this in case some dynamic object refers to this symbol. */
2309
2310 /*ARGSUSED*/
2311 boolean
2312 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2313 bfd *output_bfd ATTRIBUTE_UNUSED;
2314 struct bfd_link_info *info;
2315 const char *name;
2316 boolean provide;
2317 {
2318 struct elf_link_hash_entry *h;
2319
2320 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2321 return true;
2322
2323 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2324 if (h == NULL)
2325 return false;
2326
2327 if (h->root.type == bfd_link_hash_new)
2328 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2329
2330 /* If this symbol is being provided by the linker script, and it is
2331 currently defined by a dynamic object, but not by a regular
2332 object, then mark it as undefined so that the generic linker will
2333 force the correct value. */
2334 if (provide
2335 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2336 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2337 h->root.type = bfd_link_hash_undefined;
2338
2339 /* If this symbol is not being provided by the linker script, and it is
2340 currently defined by a dynamic object, but not by a regular object,
2341 then clear out any version information because the symbol will not be
2342 associated with the dynamic object any more. */
2343 if (!provide
2344 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2345 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2346 h->verinfo.verdef = NULL;
2347
2348 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2349 h->type = STT_OBJECT;
2350
2351 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2352 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2353 || info->shared)
2354 && h->dynindx == -1)
2355 {
2356 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2357 return false;
2358
2359 /* If this is a weak defined symbol, and we know a corresponding
2360 real symbol from the same dynamic object, make sure the real
2361 symbol is also made into a dynamic symbol. */
2362 if (h->weakdef != NULL
2363 && h->weakdef->dynindx == -1)
2364 {
2365 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2366 return false;
2367 }
2368 }
2369
2370 return true;
2371 }
2372 \f
2373 /* This structure is used to pass information to
2374 elf_link_assign_sym_version. */
2375
2376 struct elf_assign_sym_version_info
2377 {
2378 /* Output BFD. */
2379 bfd *output_bfd;
2380 /* General link information. */
2381 struct bfd_link_info *info;
2382 /* Version tree. */
2383 struct bfd_elf_version_tree *verdefs;
2384 /* Whether we are exporting all dynamic symbols. */
2385 boolean export_dynamic;
2386 /* Whether we had a failure. */
2387 boolean failed;
2388 };
2389
2390 /* This structure is used to pass information to
2391 elf_link_find_version_dependencies. */
2392
2393 struct elf_find_verdep_info
2394 {
2395 /* Output BFD. */
2396 bfd *output_bfd;
2397 /* General link information. */
2398 struct bfd_link_info *info;
2399 /* The number of dependencies. */
2400 unsigned int vers;
2401 /* Whether we had a failure. */
2402 boolean failed;
2403 };
2404
2405 /* Array used to determine the number of hash table buckets to use
2406 based on the number of symbols there are. If there are fewer than
2407 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2408 fewer than 37 we use 17 buckets, and so forth. We never use more
2409 than 32771 buckets. */
2410
2411 static const size_t elf_buckets[] =
2412 {
2413 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2414 16411, 32771, 0
2415 };
2416
2417 /* Compute bucket count for hashing table. We do not use a static set
2418 of possible tables sizes anymore. Instead we determine for all
2419 possible reasonable sizes of the table the outcome (i.e., the
2420 number of collisions etc) and choose the best solution. The
2421 weighting functions are not too simple to allow the table to grow
2422 without bounds. Instead one of the weighting factors is the size.
2423 Therefore the result is always a good payoff between few collisions
2424 (= short chain lengths) and table size. */
2425 static size_t
2426 compute_bucket_count (info)
2427 struct bfd_link_info *info;
2428 {
2429 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2430 size_t best_size = 0;
2431 unsigned long int *hashcodes;
2432 unsigned long int *hashcodesp;
2433 unsigned long int i;
2434
2435 /* Compute the hash values for all exported symbols. At the same
2436 time store the values in an array so that we could use them for
2437 optimizations. */
2438 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2439 * sizeof (unsigned long int));
2440 if (hashcodes == NULL)
2441 return 0;
2442 hashcodesp = hashcodes;
2443
2444 /* Put all hash values in HASHCODES. */
2445 elf_link_hash_traverse (elf_hash_table (info),
2446 elf_collect_hash_codes, &hashcodesp);
2447
2448 /* We have a problem here. The following code to optimize the table
2449 size requires an integer type with more the 32 bits. If
2450 BFD_HOST_U_64_BIT is set we know about such a type. */
2451 #ifdef BFD_HOST_U_64_BIT
2452 if (info->optimize == true)
2453 {
2454 unsigned long int nsyms = hashcodesp - hashcodes;
2455 size_t minsize;
2456 size_t maxsize;
2457 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2458 unsigned long int *counts ;
2459
2460 /* Possible optimization parameters: if we have NSYMS symbols we say
2461 that the hashing table must at least have NSYMS/4 and at most
2462 2*NSYMS buckets. */
2463 minsize = nsyms / 4;
2464 if (minsize == 0)
2465 minsize = 1;
2466 best_size = maxsize = nsyms * 2;
2467
2468 /* Create array where we count the collisions in. We must use bfd_malloc
2469 since the size could be large. */
2470 counts = (unsigned long int *) bfd_malloc (maxsize
2471 * sizeof (unsigned long int));
2472 if (counts == NULL)
2473 {
2474 free (hashcodes);
2475 return 0;
2476 }
2477
2478 /* Compute the "optimal" size for the hash table. The criteria is a
2479 minimal chain length. The minor criteria is (of course) the size
2480 of the table. */
2481 for (i = minsize; i < maxsize; ++i)
2482 {
2483 /* Walk through the array of hashcodes and count the collisions. */
2484 BFD_HOST_U_64_BIT max;
2485 unsigned long int j;
2486 unsigned long int fact;
2487
2488 memset (counts, '\0', i * sizeof (unsigned long int));
2489
2490 /* Determine how often each hash bucket is used. */
2491 for (j = 0; j < nsyms; ++j)
2492 ++counts[hashcodes[j] % i];
2493
2494 /* For the weight function we need some information about the
2495 pagesize on the target. This is information need not be 100%
2496 accurate. Since this information is not available (so far) we
2497 define it here to a reasonable default value. If it is crucial
2498 to have a better value some day simply define this value. */
2499 # ifndef BFD_TARGET_PAGESIZE
2500 # define BFD_TARGET_PAGESIZE (4096)
2501 # endif
2502
2503 /* We in any case need 2 + NSYMS entries for the size values and
2504 the chains. */
2505 max = (2 + nsyms) * (ARCH_SIZE / 8);
2506
2507 # if 1
2508 /* Variant 1: optimize for short chains. We add the squares
2509 of all the chain lengths (which favous many small chain
2510 over a few long chains). */
2511 for (j = 0; j < i; ++j)
2512 max += counts[j] * counts[j];
2513
2514 /* This adds penalties for the overall size of the table. */
2515 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2516 max *= fact * fact;
2517 # else
2518 /* Variant 2: Optimize a lot more for small table. Here we
2519 also add squares of the size but we also add penalties for
2520 empty slots (the +1 term). */
2521 for (j = 0; j < i; ++j)
2522 max += (1 + counts[j]) * (1 + counts[j]);
2523
2524 /* The overall size of the table is considered, but not as
2525 strong as in variant 1, where it is squared. */
2526 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2527 max *= fact;
2528 # endif
2529
2530 /* Compare with current best results. */
2531 if (max < best_chlen)
2532 {
2533 best_chlen = max;
2534 best_size = i;
2535 }
2536 }
2537
2538 free (counts);
2539 }
2540 else
2541 #endif /* defined (BFD_HOST_U_64_BIT) */
2542 {
2543 /* This is the fallback solution if no 64bit type is available or if we
2544 are not supposed to spend much time on optimizations. We select the
2545 bucket count using a fixed set of numbers. */
2546 for (i = 0; elf_buckets[i] != 0; i++)
2547 {
2548 best_size = elf_buckets[i];
2549 if (dynsymcount < elf_buckets[i + 1])
2550 break;
2551 }
2552 }
2553
2554 /* Free the arrays we needed. */
2555 free (hashcodes);
2556
2557 return best_size;
2558 }
2559
2560 /* Set up the sizes and contents of the ELF dynamic sections. This is
2561 called by the ELF linker emulation before_allocation routine. We
2562 must set the sizes of the sections before the linker sets the
2563 addresses of the various sections. */
2564
2565 boolean
2566 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2567 export_dynamic, filter_shlib,
2568 auxiliary_filters, info, sinterpptr,
2569 verdefs)
2570 bfd *output_bfd;
2571 const char *soname;
2572 const char *rpath;
2573 boolean export_dynamic;
2574 const char *filter_shlib;
2575 const char * const *auxiliary_filters;
2576 struct bfd_link_info *info;
2577 asection **sinterpptr;
2578 struct bfd_elf_version_tree *verdefs;
2579 {
2580 bfd_size_type soname_indx;
2581 bfd *dynobj;
2582 struct elf_backend_data *bed;
2583 struct elf_assign_sym_version_info asvinfo;
2584
2585 *sinterpptr = NULL;
2586
2587 soname_indx = (bfd_size_type) -1;
2588
2589 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2590 return true;
2591
2592 /* The backend may have to create some sections regardless of whether
2593 we're dynamic or not. */
2594 bed = get_elf_backend_data (output_bfd);
2595 if (bed->elf_backend_always_size_sections
2596 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2597 return false;
2598
2599 dynobj = elf_hash_table (info)->dynobj;
2600
2601 /* If there were no dynamic objects in the link, there is nothing to
2602 do here. */
2603 if (dynobj == NULL)
2604 return true;
2605
2606 /* If we are supposed to export all symbols into the dynamic symbol
2607 table (this is not the normal case), then do so. */
2608 if (export_dynamic)
2609 {
2610 struct elf_info_failed eif;
2611
2612 eif.failed = false;
2613 eif.info = info;
2614 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2615 (PTR) &eif);
2616 if (eif.failed)
2617 return false;
2618 }
2619
2620 if (elf_hash_table (info)->dynamic_sections_created)
2621 {
2622 struct elf_info_failed eif;
2623 struct elf_link_hash_entry *h;
2624 bfd_size_type strsize;
2625
2626 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2627 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2628
2629 if (soname != NULL)
2630 {
2631 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2632 soname, true, true);
2633 if (soname_indx == (bfd_size_type) -1
2634 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2635 return false;
2636 }
2637
2638 if (info->symbolic)
2639 {
2640 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2641 return false;
2642 }
2643
2644 if (rpath != NULL)
2645 {
2646 bfd_size_type indx;
2647
2648 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2649 true, true);
2650 if (indx == (bfd_size_type) -1
2651 || ! elf_add_dynamic_entry (info, DT_RPATH, indx))
2652 return false;
2653 }
2654
2655 if (filter_shlib != NULL)
2656 {
2657 bfd_size_type indx;
2658
2659 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2660 filter_shlib, true, true);
2661 if (indx == (bfd_size_type) -1
2662 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2663 return false;
2664 }
2665
2666 if (auxiliary_filters != NULL)
2667 {
2668 const char * const *p;
2669
2670 for (p = auxiliary_filters; *p != NULL; p++)
2671 {
2672 bfd_size_type indx;
2673
2674 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2675 *p, true, true);
2676 if (indx == (bfd_size_type) -1
2677 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2678 return false;
2679 }
2680 }
2681
2682 /* Attach all the symbols to their version information. */
2683 asvinfo.output_bfd = output_bfd;
2684 asvinfo.info = info;
2685 asvinfo.verdefs = verdefs;
2686 asvinfo.export_dynamic = export_dynamic;
2687 asvinfo.failed = false;
2688
2689 elf_link_hash_traverse (elf_hash_table (info),
2690 elf_link_assign_sym_version,
2691 (PTR) &asvinfo);
2692 if (asvinfo.failed)
2693 return false;
2694
2695 /* Find all symbols which were defined in a dynamic object and make
2696 the backend pick a reasonable value for them. */
2697 eif.failed = false;
2698 eif.info = info;
2699 elf_link_hash_traverse (elf_hash_table (info),
2700 elf_adjust_dynamic_symbol,
2701 (PTR) &eif);
2702 if (eif.failed)
2703 return false;
2704
2705 /* Add some entries to the .dynamic section. We fill in some of the
2706 values later, in elf_bfd_final_link, but we must add the entries
2707 now so that we know the final size of the .dynamic section. */
2708
2709 /* If there are initialization and/or finalization functions to
2710 call then add the corresponding DT_INIT/DT_FINI entries. */
2711 h = (info->init_function
2712 ? elf_link_hash_lookup (elf_hash_table (info),
2713 info->init_function, false,
2714 false, false)
2715 : NULL);
2716 if (h != NULL
2717 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2718 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2719 {
2720 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
2721 return false;
2722 }
2723 h = (info->fini_function
2724 ? elf_link_hash_lookup (elf_hash_table (info),
2725 info->fini_function, false,
2726 false, false)
2727 : NULL);
2728 if (h != NULL
2729 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
2730 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
2731 {
2732 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
2733 return false;
2734 }
2735
2736 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
2737 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
2738 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
2739 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
2740 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
2741 || ! elf_add_dynamic_entry (info, DT_SYMENT,
2742 sizeof (Elf_External_Sym)))
2743 return false;
2744 }
2745
2746 /* The backend must work out the sizes of all the other dynamic
2747 sections. */
2748 if (bed->elf_backend_size_dynamic_sections
2749 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
2750 return false;
2751
2752 if (elf_hash_table (info)->dynamic_sections_created)
2753 {
2754 size_t dynsymcount;
2755 asection *s;
2756 size_t bucketcount = 0;
2757 Elf_Internal_Sym isym;
2758 size_t hash_entry_size;
2759
2760 /* Set up the version definition section. */
2761 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
2762 BFD_ASSERT (s != NULL);
2763
2764 /* We may have created additional version definitions if we are
2765 just linking a regular application. */
2766 verdefs = asvinfo.verdefs;
2767
2768 if (verdefs == NULL)
2769 _bfd_strip_section_from_output (s);
2770 else
2771 {
2772 unsigned int cdefs;
2773 bfd_size_type size;
2774 struct bfd_elf_version_tree *t;
2775 bfd_byte *p;
2776 Elf_Internal_Verdef def;
2777 Elf_Internal_Verdaux defaux;
2778
2779 cdefs = 0;
2780 size = 0;
2781
2782 /* Make space for the base version. */
2783 size += sizeof (Elf_External_Verdef);
2784 size += sizeof (Elf_External_Verdaux);
2785 ++cdefs;
2786
2787 for (t = verdefs; t != NULL; t = t->next)
2788 {
2789 struct bfd_elf_version_deps *n;
2790
2791 size += sizeof (Elf_External_Verdef);
2792 size += sizeof (Elf_External_Verdaux);
2793 ++cdefs;
2794
2795 for (n = t->deps; n != NULL; n = n->next)
2796 size += sizeof (Elf_External_Verdaux);
2797 }
2798
2799 s->_raw_size = size;
2800 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
2801 if (s->contents == NULL && s->_raw_size != 0)
2802 return false;
2803
2804 /* Fill in the version definition section. */
2805
2806 p = s->contents;
2807
2808 def.vd_version = VER_DEF_CURRENT;
2809 def.vd_flags = VER_FLG_BASE;
2810 def.vd_ndx = 1;
2811 def.vd_cnt = 1;
2812 def.vd_aux = sizeof (Elf_External_Verdef);
2813 def.vd_next = (sizeof (Elf_External_Verdef)
2814 + sizeof (Elf_External_Verdaux));
2815
2816 if (soname_indx != (bfd_size_type) -1)
2817 {
2818 def.vd_hash = bfd_elf_hash (soname);
2819 defaux.vda_name = soname_indx;
2820 }
2821 else
2822 {
2823 const char *name;
2824 bfd_size_type indx;
2825
2826 name = output_bfd->filename;
2827 def.vd_hash = bfd_elf_hash (name);
2828 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2829 name, true, false);
2830 if (indx == (bfd_size_type) -1)
2831 return false;
2832 defaux.vda_name = indx;
2833 }
2834 defaux.vda_next = 0;
2835
2836 _bfd_elf_swap_verdef_out (output_bfd, &def,
2837 (Elf_External_Verdef *)p);
2838 p += sizeof (Elf_External_Verdef);
2839 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2840 (Elf_External_Verdaux *) p);
2841 p += sizeof (Elf_External_Verdaux);
2842
2843 for (t = verdefs; t != NULL; t = t->next)
2844 {
2845 unsigned int cdeps;
2846 struct bfd_elf_version_deps *n;
2847 struct elf_link_hash_entry *h;
2848
2849 cdeps = 0;
2850 for (n = t->deps; n != NULL; n = n->next)
2851 ++cdeps;
2852
2853 /* Add a symbol representing this version. */
2854 h = NULL;
2855 if (! (_bfd_generic_link_add_one_symbol
2856 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
2857 (bfd_vma) 0, (const char *) NULL, false,
2858 get_elf_backend_data (dynobj)->collect,
2859 (struct bfd_link_hash_entry **) &h)))
2860 return false;
2861 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
2862 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2863 h->type = STT_OBJECT;
2864 h->verinfo.vertree = t;
2865
2866 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2867 return false;
2868
2869 def.vd_version = VER_DEF_CURRENT;
2870 def.vd_flags = 0;
2871 if (t->globals == NULL && t->locals == NULL && ! t->used)
2872 def.vd_flags |= VER_FLG_WEAK;
2873 def.vd_ndx = t->vernum + 1;
2874 def.vd_cnt = cdeps + 1;
2875 def.vd_hash = bfd_elf_hash (t->name);
2876 def.vd_aux = sizeof (Elf_External_Verdef);
2877 if (t->next != NULL)
2878 def.vd_next = (sizeof (Elf_External_Verdef)
2879 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
2880 else
2881 def.vd_next = 0;
2882
2883 _bfd_elf_swap_verdef_out (output_bfd, &def,
2884 (Elf_External_Verdef *) p);
2885 p += sizeof (Elf_External_Verdef);
2886
2887 defaux.vda_name = h->dynstr_index;
2888 if (t->deps == NULL)
2889 defaux.vda_next = 0;
2890 else
2891 defaux.vda_next = sizeof (Elf_External_Verdaux);
2892 t->name_indx = defaux.vda_name;
2893
2894 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2895 (Elf_External_Verdaux *) p);
2896 p += sizeof (Elf_External_Verdaux);
2897
2898 for (n = t->deps; n != NULL; n = n->next)
2899 {
2900 if (n->version_needed == NULL)
2901 {
2902 /* This can happen if there was an error in the
2903 version script. */
2904 defaux.vda_name = 0;
2905 }
2906 else
2907 defaux.vda_name = n->version_needed->name_indx;
2908 if (n->next == NULL)
2909 defaux.vda_next = 0;
2910 else
2911 defaux.vda_next = sizeof (Elf_External_Verdaux);
2912
2913 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
2914 (Elf_External_Verdaux *) p);
2915 p += sizeof (Elf_External_Verdaux);
2916 }
2917 }
2918
2919 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
2920 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
2921 return false;
2922
2923 elf_tdata (output_bfd)->cverdefs = cdefs;
2924 }
2925
2926 /* Work out the size of the version reference section. */
2927
2928 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
2929 BFD_ASSERT (s != NULL);
2930 {
2931 struct elf_find_verdep_info sinfo;
2932
2933 sinfo.output_bfd = output_bfd;
2934 sinfo.info = info;
2935 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
2936 if (sinfo.vers == 0)
2937 sinfo.vers = 1;
2938 sinfo.failed = false;
2939
2940 elf_link_hash_traverse (elf_hash_table (info),
2941 elf_link_find_version_dependencies,
2942 (PTR) &sinfo);
2943
2944 if (elf_tdata (output_bfd)->verref == NULL)
2945 _bfd_strip_section_from_output (s);
2946 else
2947 {
2948 Elf_Internal_Verneed *t;
2949 unsigned int size;
2950 unsigned int crefs;
2951 bfd_byte *p;
2952
2953 /* Build the version definition section. */
2954 size = 0;
2955 crefs = 0;
2956 for (t = elf_tdata (output_bfd)->verref;
2957 t != NULL;
2958 t = t->vn_nextref)
2959 {
2960 Elf_Internal_Vernaux *a;
2961
2962 size += sizeof (Elf_External_Verneed);
2963 ++crefs;
2964 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2965 size += sizeof (Elf_External_Vernaux);
2966 }
2967
2968 s->_raw_size = size;
2969 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
2970 if (s->contents == NULL)
2971 return false;
2972
2973 p = s->contents;
2974 for (t = elf_tdata (output_bfd)->verref;
2975 t != NULL;
2976 t = t->vn_nextref)
2977 {
2978 unsigned int caux;
2979 Elf_Internal_Vernaux *a;
2980 bfd_size_type indx;
2981
2982 caux = 0;
2983 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2984 ++caux;
2985
2986 t->vn_version = VER_NEED_CURRENT;
2987 t->vn_cnt = caux;
2988 if (elf_dt_name (t->vn_bfd) != NULL)
2989 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2990 elf_dt_name (t->vn_bfd),
2991 true, false);
2992 else
2993 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2994 t->vn_bfd->filename, true, false);
2995 if (indx == (bfd_size_type) -1)
2996 return false;
2997 t->vn_file = indx;
2998 t->vn_aux = sizeof (Elf_External_Verneed);
2999 if (t->vn_nextref == NULL)
3000 t->vn_next = 0;
3001 else
3002 t->vn_next = (sizeof (Elf_External_Verneed)
3003 + caux * sizeof (Elf_External_Vernaux));
3004
3005 _bfd_elf_swap_verneed_out (output_bfd, t,
3006 (Elf_External_Verneed *) p);
3007 p += sizeof (Elf_External_Verneed);
3008
3009 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3010 {
3011 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3012 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3013 a->vna_nodename, true, false);
3014 if (indx == (bfd_size_type) -1)
3015 return false;
3016 a->vna_name = indx;
3017 if (a->vna_nextptr == NULL)
3018 a->vna_next = 0;
3019 else
3020 a->vna_next = sizeof (Elf_External_Vernaux);
3021
3022 _bfd_elf_swap_vernaux_out (output_bfd, a,
3023 (Elf_External_Vernaux *) p);
3024 p += sizeof (Elf_External_Vernaux);
3025 }
3026 }
3027
3028 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3029 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3030 return false;
3031
3032 elf_tdata (output_bfd)->cverrefs = crefs;
3033 }
3034 }
3035
3036 /* Assign dynsym indicies. In a shared library we generate a
3037 section symbol for each output section, which come first.
3038 Next come all of the back-end allocated local dynamic syms,
3039 followed by the rest of the global symbols. */
3040
3041 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3042
3043 /* Work out the size of the symbol version section. */
3044 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3045 BFD_ASSERT (s != NULL);
3046 if (dynsymcount == 0
3047 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3048 {
3049 _bfd_strip_section_from_output (s);
3050 /* The DYNSYMCOUNT might have changed if we were going to
3051 output a dynamic symbol table entry for S. */
3052 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3053 }
3054 else
3055 {
3056 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3057 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3058 if (s->contents == NULL)
3059 return false;
3060
3061 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3062 return false;
3063 }
3064
3065 /* Set the size of the .dynsym and .hash sections. We counted
3066 the number of dynamic symbols in elf_link_add_object_symbols.
3067 We will build the contents of .dynsym and .hash when we build
3068 the final symbol table, because until then we do not know the
3069 correct value to give the symbols. We built the .dynstr
3070 section as we went along in elf_link_add_object_symbols. */
3071 s = bfd_get_section_by_name (dynobj, ".dynsym");
3072 BFD_ASSERT (s != NULL);
3073 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3074 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3075 if (s->contents == NULL && s->_raw_size != 0)
3076 return false;
3077
3078 /* The first entry in .dynsym is a dummy symbol. */
3079 isym.st_value = 0;
3080 isym.st_size = 0;
3081 isym.st_name = 0;
3082 isym.st_info = 0;
3083 isym.st_other = 0;
3084 isym.st_shndx = 0;
3085 elf_swap_symbol_out (output_bfd, &isym,
3086 (PTR) (Elf_External_Sym *) s->contents);
3087
3088 /* Compute the size of the hashing table. As a side effect this
3089 computes the hash values for all the names we export. */
3090 bucketcount = compute_bucket_count (info);
3091
3092 s = bfd_get_section_by_name (dynobj, ".hash");
3093 BFD_ASSERT (s != NULL);
3094 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3095 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3096 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3097 if (s->contents == NULL)
3098 return false;
3099 memset (s->contents, 0, (size_t) s->_raw_size);
3100
3101 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3102 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3103 s->contents + hash_entry_size);
3104
3105 elf_hash_table (info)->bucketcount = bucketcount;
3106
3107 s = bfd_get_section_by_name (dynobj, ".dynstr");
3108 BFD_ASSERT (s != NULL);
3109 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3110
3111 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3112 return false;
3113 }
3114
3115 return true;
3116 }
3117 \f
3118 /* Fix up the flags for a symbol. This handles various cases which
3119 can only be fixed after all the input files are seen. This is
3120 currently called by both adjust_dynamic_symbol and
3121 assign_sym_version, which is unnecessary but perhaps more robust in
3122 the face of future changes. */
3123
3124 static boolean
3125 elf_fix_symbol_flags (h, eif)
3126 struct elf_link_hash_entry *h;
3127 struct elf_info_failed *eif;
3128 {
3129 /* If this symbol was mentioned in a non-ELF file, try to set
3130 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3131 permit a non-ELF file to correctly refer to a symbol defined in
3132 an ELF dynamic object. */
3133 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3134 {
3135 if (h->root.type != bfd_link_hash_defined
3136 && h->root.type != bfd_link_hash_defweak)
3137 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3138 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3139 else
3140 {
3141 if (h->root.u.def.section->owner != NULL
3142 && (bfd_get_flavour (h->root.u.def.section->owner)
3143 == bfd_target_elf_flavour))
3144 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3145 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3146 else
3147 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3148 }
3149
3150 if (h->dynindx == -1
3151 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3152 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3153 {
3154 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3155 {
3156 eif->failed = true;
3157 return false;
3158 }
3159 }
3160 }
3161 else
3162 {
3163 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3164 was first seen in a non-ELF file. Fortunately, if the symbol
3165 was first seen in an ELF file, we're probably OK unless the
3166 symbol was defined in a non-ELF file. Catch that case here.
3167 FIXME: We're still in trouble if the symbol was first seen in
3168 a dynamic object, and then later in a non-ELF regular object. */
3169 if ((h->root.type == bfd_link_hash_defined
3170 || h->root.type == bfd_link_hash_defweak)
3171 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3172 && (h->root.u.def.section->owner != NULL
3173 ? (bfd_get_flavour (h->root.u.def.section->owner)
3174 != bfd_target_elf_flavour)
3175 : (bfd_is_abs_section (h->root.u.def.section)
3176 && (h->elf_link_hash_flags
3177 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3178 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3179 }
3180
3181 /* If this is a final link, and the symbol was defined as a common
3182 symbol in a regular object file, and there was no definition in
3183 any dynamic object, then the linker will have allocated space for
3184 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3185 flag will not have been set. */
3186 if (h->root.type == bfd_link_hash_defined
3187 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3188 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3189 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3190 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3191 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3192
3193 /* If -Bsymbolic was used (which means to bind references to global
3194 symbols to the definition within the shared object), and this
3195 symbol was defined in a regular object, then it actually doesn't
3196 need a PLT entry. */
3197 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3198 && eif->info->shared
3199 && eif->info->symbolic
3200 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3201 {
3202 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3203 h->plt.offset = (bfd_vma) -1;
3204 }
3205
3206 return true;
3207 }
3208
3209 /* Make the backend pick a good value for a dynamic symbol. This is
3210 called via elf_link_hash_traverse, and also calls itself
3211 recursively. */
3212
3213 static boolean
3214 elf_adjust_dynamic_symbol (h, data)
3215 struct elf_link_hash_entry *h;
3216 PTR data;
3217 {
3218 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3219 bfd *dynobj;
3220 struct elf_backend_data *bed;
3221
3222 /* Ignore indirect symbols. These are added by the versioning code. */
3223 if (h->root.type == bfd_link_hash_indirect)
3224 return true;
3225
3226 /* Fix the symbol flags. */
3227 if (! elf_fix_symbol_flags (h, eif))
3228 return false;
3229
3230 /* If this symbol does not require a PLT entry, and it is not
3231 defined by a dynamic object, or is not referenced by a regular
3232 object, ignore it. We do have to handle a weak defined symbol,
3233 even if no regular object refers to it, if we decided to add it
3234 to the dynamic symbol table. FIXME: Do we normally need to worry
3235 about symbols which are defined by one dynamic object and
3236 referenced by another one? */
3237 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3238 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3239 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3240 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3241 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3242 {
3243 h->plt.offset = (bfd_vma) -1;
3244 return true;
3245 }
3246
3247 /* If we've already adjusted this symbol, don't do it again. This
3248 can happen via a recursive call. */
3249 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3250 return true;
3251
3252 /* Don't look at this symbol again. Note that we must set this
3253 after checking the above conditions, because we may look at a
3254 symbol once, decide not to do anything, and then get called
3255 recursively later after REF_REGULAR is set below. */
3256 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3257
3258 /* If this is a weak definition, and we know a real definition, and
3259 the real symbol is not itself defined by a regular object file,
3260 then get a good value for the real definition. We handle the
3261 real symbol first, for the convenience of the backend routine.
3262
3263 Note that there is a confusing case here. If the real definition
3264 is defined by a regular object file, we don't get the real symbol
3265 from the dynamic object, but we do get the weak symbol. If the
3266 processor backend uses a COPY reloc, then if some routine in the
3267 dynamic object changes the real symbol, we will not see that
3268 change in the corresponding weak symbol. This is the way other
3269 ELF linkers work as well, and seems to be a result of the shared
3270 library model.
3271
3272 I will clarify this issue. Most SVR4 shared libraries define the
3273 variable _timezone and define timezone as a weak synonym. The
3274 tzset call changes _timezone. If you write
3275 extern int timezone;
3276 int _timezone = 5;
3277 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3278 you might expect that, since timezone is a synonym for _timezone,
3279 the same number will print both times. However, if the processor
3280 backend uses a COPY reloc, then actually timezone will be copied
3281 into your process image, and, since you define _timezone
3282 yourself, _timezone will not. Thus timezone and _timezone will
3283 wind up at different memory locations. The tzset call will set
3284 _timezone, leaving timezone unchanged. */
3285
3286 if (h->weakdef != NULL)
3287 {
3288 struct elf_link_hash_entry *weakdef;
3289
3290 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3291 || h->root.type == bfd_link_hash_defweak);
3292 weakdef = h->weakdef;
3293 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3294 || weakdef->root.type == bfd_link_hash_defweak);
3295 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3296 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3297 {
3298 /* This symbol is defined by a regular object file, so we
3299 will not do anything special. Clear weakdef for the
3300 convenience of the processor backend. */
3301 h->weakdef = NULL;
3302 }
3303 else
3304 {
3305 /* There is an implicit reference by a regular object file
3306 via the weak symbol. */
3307 weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3308 if (h->weakdef->elf_link_hash_flags
3309 & ELF_LINK_HASH_REF_REGULAR_NONWEAK)
3310 weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
3311 if (! elf_adjust_dynamic_symbol (weakdef, (PTR) eif))
3312 return false;
3313 }
3314 }
3315
3316 /* If a symbol has no type and no size and does not require a PLT
3317 entry, then we are probably about to do the wrong thing here: we
3318 are probably going to create a COPY reloc for an empty object.
3319 This case can arise when a shared object is built with assembly
3320 code, and the assembly code fails to set the symbol type. */
3321 if (h->size == 0
3322 && h->type == STT_NOTYPE
3323 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3324 (*_bfd_error_handler)
3325 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3326 h->root.root.string);
3327
3328 dynobj = elf_hash_table (eif->info)->dynobj;
3329 bed = get_elf_backend_data (dynobj);
3330 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3331 {
3332 eif->failed = true;
3333 return false;
3334 }
3335
3336 return true;
3337 }
3338 \f
3339 /* This routine is used to export all defined symbols into the dynamic
3340 symbol table. It is called via elf_link_hash_traverse. */
3341
3342 static boolean
3343 elf_export_symbol (h, data)
3344 struct elf_link_hash_entry *h;
3345 PTR data;
3346 {
3347 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3348
3349 /* Ignore indirect symbols. These are added by the versioning code. */
3350 if (h->root.type == bfd_link_hash_indirect)
3351 return true;
3352
3353 if (h->dynindx == -1
3354 && (h->elf_link_hash_flags
3355 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3356 {
3357 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3358 {
3359 eif->failed = true;
3360 return false;
3361 }
3362 }
3363
3364 return true;
3365 }
3366 \f
3367 /* Look through the symbols which are defined in other shared
3368 libraries and referenced here. Update the list of version
3369 dependencies. This will be put into the .gnu.version_r section.
3370 This function is called via elf_link_hash_traverse. */
3371
3372 static boolean
3373 elf_link_find_version_dependencies (h, data)
3374 struct elf_link_hash_entry *h;
3375 PTR data;
3376 {
3377 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3378 Elf_Internal_Verneed *t;
3379 Elf_Internal_Vernaux *a;
3380
3381 /* We only care about symbols defined in shared objects with version
3382 information. */
3383 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3384 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3385 || h->dynindx == -1
3386 || h->verinfo.verdef == NULL)
3387 return true;
3388
3389 /* See if we already know about this version. */
3390 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3391 {
3392 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3393 continue;
3394
3395 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3396 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3397 return true;
3398
3399 break;
3400 }
3401
3402 /* This is a new version. Add it to tree we are building. */
3403
3404 if (t == NULL)
3405 {
3406 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3407 if (t == NULL)
3408 {
3409 rinfo->failed = true;
3410 return false;
3411 }
3412
3413 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3414 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3415 elf_tdata (rinfo->output_bfd)->verref = t;
3416 }
3417
3418 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3419
3420 /* Note that we are copying a string pointer here, and testing it
3421 above. If bfd_elf_string_from_elf_section is ever changed to
3422 discard the string data when low in memory, this will have to be
3423 fixed. */
3424 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3425
3426 a->vna_flags = h->verinfo.verdef->vd_flags;
3427 a->vna_nextptr = t->vn_auxptr;
3428
3429 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3430 ++rinfo->vers;
3431
3432 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3433
3434 t->vn_auxptr = a;
3435
3436 return true;
3437 }
3438
3439 /* Figure out appropriate versions for all the symbols. We may not
3440 have the version number script until we have read all of the input
3441 files, so until that point we don't know which symbols should be
3442 local. This function is called via elf_link_hash_traverse. */
3443
3444 static boolean
3445 elf_link_assign_sym_version (h, data)
3446 struct elf_link_hash_entry *h;
3447 PTR data;
3448 {
3449 struct elf_assign_sym_version_info *sinfo =
3450 (struct elf_assign_sym_version_info *) data;
3451 struct bfd_link_info *info = sinfo->info;
3452 struct elf_info_failed eif;
3453 char *p;
3454
3455 /* Fix the symbol flags. */
3456 eif.failed = false;
3457 eif.info = info;
3458 if (! elf_fix_symbol_flags (h, &eif))
3459 {
3460 if (eif.failed)
3461 sinfo->failed = true;
3462 return false;
3463 }
3464
3465 /* We only need version numbers for symbols defined in regular
3466 objects. */
3467 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3468 return true;
3469
3470 p = strchr (h->root.root.string, ELF_VER_CHR);
3471 if (p != NULL && h->verinfo.vertree == NULL)
3472 {
3473 struct bfd_elf_version_tree *t;
3474 boolean hidden;
3475
3476 hidden = true;
3477
3478 /* There are two consecutive ELF_VER_CHR characters if this is
3479 not a hidden symbol. */
3480 ++p;
3481 if (*p == ELF_VER_CHR)
3482 {
3483 hidden = false;
3484 ++p;
3485 }
3486
3487 /* If there is no version string, we can just return out. */
3488 if (*p == '\0')
3489 {
3490 if (hidden)
3491 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3492 return true;
3493 }
3494
3495 /* Look for the version. If we find it, it is no longer weak. */
3496 for (t = sinfo->verdefs; t != NULL; t = t->next)
3497 {
3498 if (strcmp (t->name, p) == 0)
3499 {
3500 int len;
3501 char *alc;
3502 struct bfd_elf_version_expr *d;
3503
3504 len = p - h->root.root.string;
3505 alc = bfd_alloc (sinfo->output_bfd, len);
3506 if (alc == NULL)
3507 return false;
3508 strncpy (alc, h->root.root.string, len - 1);
3509 alc[len - 1] = '\0';
3510 if (alc[len - 2] == ELF_VER_CHR)
3511 alc[len - 2] = '\0';
3512
3513 h->verinfo.vertree = t;
3514 t->used = true;
3515 d = NULL;
3516
3517 if (t->globals != NULL)
3518 {
3519 for (d = t->globals; d != NULL; d = d->next)
3520 if ((*d->match) (d, alc))
3521 break;
3522 }
3523
3524 /* See if there is anything to force this symbol to
3525 local scope. */
3526 if (d == NULL && t->locals != NULL)
3527 {
3528 for (d = t->locals; d != NULL; d = d->next)
3529 {
3530 if ((*d->match) (d, alc))
3531 {
3532 if (h->dynindx != -1
3533 && info->shared
3534 && ! sinfo->export_dynamic)
3535 {
3536 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3537 h->elf_link_hash_flags &=~
3538 ELF_LINK_HASH_NEEDS_PLT;
3539 h->dynindx = -1;
3540 h->plt.offset = (bfd_vma) -1;
3541 /* FIXME: The name of the symbol has
3542 already been recorded in the dynamic
3543 string table section. */
3544 }
3545
3546 break;
3547 }
3548 }
3549 }
3550
3551 bfd_release (sinfo->output_bfd, alc);
3552 break;
3553 }
3554 }
3555
3556 /* If we are building an application, we need to create a
3557 version node for this version. */
3558 if (t == NULL && ! info->shared)
3559 {
3560 struct bfd_elf_version_tree **pp;
3561 int version_index;
3562
3563 /* If we aren't going to export this symbol, we don't need
3564 to worry about it. */
3565 if (h->dynindx == -1)
3566 return true;
3567
3568 t = ((struct bfd_elf_version_tree *)
3569 bfd_alloc (sinfo->output_bfd, sizeof *t));
3570 if (t == NULL)
3571 {
3572 sinfo->failed = true;
3573 return false;
3574 }
3575
3576 t->next = NULL;
3577 t->name = p;
3578 t->globals = NULL;
3579 t->locals = NULL;
3580 t->deps = NULL;
3581 t->name_indx = (unsigned int) -1;
3582 t->used = true;
3583
3584 version_index = 1;
3585 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3586 ++version_index;
3587 t->vernum = version_index;
3588
3589 *pp = t;
3590
3591 h->verinfo.vertree = t;
3592 }
3593 else if (t == NULL)
3594 {
3595 /* We could not find the version for a symbol when
3596 generating a shared archive. Return an error. */
3597 (*_bfd_error_handler)
3598 (_("%s: undefined versioned symbol name %s"),
3599 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3600 bfd_set_error (bfd_error_bad_value);
3601 sinfo->failed = true;
3602 return false;
3603 }
3604
3605 if (hidden)
3606 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3607 }
3608
3609 /* If we don't have a version for this symbol, see if we can find
3610 something. */
3611 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3612 {
3613 struct bfd_elf_version_tree *t;
3614 struct bfd_elf_version_tree *deflt;
3615 struct bfd_elf_version_expr *d;
3616
3617 /* See if can find what version this symbol is in. If the
3618 symbol is supposed to be local, then don't actually register
3619 it. */
3620 deflt = NULL;
3621 for (t = sinfo->verdefs; t != NULL; t = t->next)
3622 {
3623 if (t->globals != NULL)
3624 {
3625 for (d = t->globals; d != NULL; d = d->next)
3626 {
3627 if ((*d->match) (d, h->root.root.string))
3628 {
3629 h->verinfo.vertree = t;
3630 break;
3631 }
3632 }
3633
3634 if (d != NULL)
3635 break;
3636 }
3637
3638 if (t->locals != NULL)
3639 {
3640 for (d = t->locals; d != NULL; d = d->next)
3641 {
3642 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3643 deflt = t;
3644 else if ((*d->match) (d, h->root.root.string))
3645 {
3646 h->verinfo.vertree = t;
3647 if (h->dynindx != -1
3648 && info->shared
3649 && ! sinfo->export_dynamic)
3650 {
3651 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3652 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3653 h->dynindx = -1;
3654 h->plt.offset = (bfd_vma) -1;
3655 /* FIXME: The name of the symbol has already
3656 been recorded in the dynamic string table
3657 section. */
3658 }
3659 break;
3660 }
3661 }
3662
3663 if (d != NULL)
3664 break;
3665 }
3666 }
3667
3668 if (deflt != NULL && h->verinfo.vertree == NULL)
3669 {
3670 h->verinfo.vertree = deflt;
3671 if (h->dynindx != -1
3672 && info->shared
3673 && ! sinfo->export_dynamic)
3674 {
3675 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3676 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3677 h->dynindx = -1;
3678 h->plt.offset = (bfd_vma) -1;
3679 /* FIXME: The name of the symbol has already been
3680 recorded in the dynamic string table section. */
3681 }
3682 }
3683 }
3684
3685 return true;
3686 }
3687 \f
3688 /* Final phase of ELF linker. */
3689
3690 /* A structure we use to avoid passing large numbers of arguments. */
3691
3692 struct elf_final_link_info
3693 {
3694 /* General link information. */
3695 struct bfd_link_info *info;
3696 /* Output BFD. */
3697 bfd *output_bfd;
3698 /* Symbol string table. */
3699 struct bfd_strtab_hash *symstrtab;
3700 /* .dynsym section. */
3701 asection *dynsym_sec;
3702 /* .hash section. */
3703 asection *hash_sec;
3704 /* symbol version section (.gnu.version). */
3705 asection *symver_sec;
3706 /* Buffer large enough to hold contents of any section. */
3707 bfd_byte *contents;
3708 /* Buffer large enough to hold external relocs of any section. */
3709 PTR external_relocs;
3710 /* Buffer large enough to hold internal relocs of any section. */
3711 Elf_Internal_Rela *internal_relocs;
3712 /* Buffer large enough to hold external local symbols of any input
3713 BFD. */
3714 Elf_External_Sym *external_syms;
3715 /* Buffer large enough to hold internal local symbols of any input
3716 BFD. */
3717 Elf_Internal_Sym *internal_syms;
3718 /* Array large enough to hold a symbol index for each local symbol
3719 of any input BFD. */
3720 long *indices;
3721 /* Array large enough to hold a section pointer for each local
3722 symbol of any input BFD. */
3723 asection **sections;
3724 /* Buffer to hold swapped out symbols. */
3725 Elf_External_Sym *symbuf;
3726 /* Number of swapped out symbols in buffer. */
3727 size_t symbuf_count;
3728 /* Number of symbols which fit in symbuf. */
3729 size_t symbuf_size;
3730 };
3731
3732 static boolean elf_link_output_sym
3733 PARAMS ((struct elf_final_link_info *, const char *,
3734 Elf_Internal_Sym *, asection *));
3735 static boolean elf_link_flush_output_syms
3736 PARAMS ((struct elf_final_link_info *));
3737 static boolean elf_link_output_extsym
3738 PARAMS ((struct elf_link_hash_entry *, PTR));
3739 static boolean elf_link_input_bfd
3740 PARAMS ((struct elf_final_link_info *, bfd *));
3741 static boolean elf_reloc_link_order
3742 PARAMS ((bfd *, struct bfd_link_info *, asection *,
3743 struct bfd_link_order *));
3744
3745 /* This struct is used to pass information to elf_link_output_extsym. */
3746
3747 struct elf_outext_info
3748 {
3749 boolean failed;
3750 boolean localsyms;
3751 struct elf_final_link_info *finfo;
3752 };
3753
3754 /* Compute the size of, and allocate space for, REL_HDR which is the
3755 section header for a section containing relocations for O. */
3756
3757 static boolean
3758 elf_link_size_reloc_section (abfd, rel_hdr, o)
3759 bfd *abfd;
3760 Elf_Internal_Shdr *rel_hdr;
3761 asection *o;
3762 {
3763 register struct elf_link_hash_entry **p, **pend;
3764
3765 /* We are overestimating the size required for the relocation
3766 sections, in the case that we are using both REL and RELA
3767 relocations for a single section. In that case, RELOC_COUNT will
3768 be the total number of relocations required, and we allocate
3769 space for that many REL relocations as well as that many RELA
3770 relocations. This approximation is wasteful of disk space.
3771 However, until we keep track of how many of each kind of
3772 relocation is required, it's difficult to calculate the right
3773 value. */
3774 rel_hdr->sh_size = rel_hdr->sh_entsize * o->reloc_count;
3775
3776 /* The contents field must last into write_object_contents, so we
3777 allocate it with bfd_alloc rather than malloc. */
3778 rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size);
3779 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
3780 return false;
3781
3782 p = ((struct elf_link_hash_entry **)
3783 bfd_malloc (o->reloc_count
3784 * sizeof (struct elf_link_hash_entry *)));
3785 if (p == NULL && o->reloc_count != 0)
3786 return false;
3787
3788 elf_section_data (o)->rel_hashes = p;
3789 pend = p + o->reloc_count;
3790 for (; p < pend; p++)
3791 *p = NULL;
3792
3793 return true;
3794 }
3795
3796 /* When performing a relocateable link, the input relocations are
3797 preserved. But, if they reference global symbols, the indices
3798 referenced must be updated. Update all the relocations in
3799 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
3800
3801 static void
3802 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
3803 bfd *abfd;
3804 Elf_Internal_Shdr *rel_hdr;
3805 unsigned int count;
3806 struct elf_link_hash_entry **rel_hash;
3807 {
3808 unsigned int i;
3809
3810 for (i = 0; i < count; i++, rel_hash++)
3811 {
3812 if (*rel_hash == NULL)
3813 continue;
3814
3815 BFD_ASSERT ((*rel_hash)->indx >= 0);
3816
3817 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
3818 {
3819 Elf_External_Rel *erel;
3820 Elf_Internal_Rel irel;
3821
3822 erel = (Elf_External_Rel *) rel_hdr->contents + i;
3823 elf_swap_reloc_in (abfd, erel, &irel);
3824 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
3825 ELF_R_TYPE (irel.r_info));
3826 elf_swap_reloc_out (abfd, &irel, erel);
3827 }
3828 else
3829 {
3830 Elf_External_Rela *erela;
3831 Elf_Internal_Rela irela;
3832
3833 BFD_ASSERT (rel_hdr->sh_entsize
3834 == sizeof (Elf_External_Rela));
3835
3836 erela = (Elf_External_Rela *) rel_hdr->contents + i;
3837 elf_swap_reloca_in (abfd, erela, &irela);
3838 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
3839 ELF_R_TYPE (irela.r_info));
3840 elf_swap_reloca_out (abfd, &irela, erela);
3841 }
3842 }
3843 }
3844
3845 /* Do the final step of an ELF link. */
3846
3847 boolean
3848 elf_bfd_final_link (abfd, info)
3849 bfd *abfd;
3850 struct bfd_link_info *info;
3851 {
3852 boolean dynamic;
3853 bfd *dynobj;
3854 struct elf_final_link_info finfo;
3855 register asection *o;
3856 register struct bfd_link_order *p;
3857 register bfd *sub;
3858 size_t max_contents_size;
3859 size_t max_external_reloc_size;
3860 size_t max_internal_reloc_count;
3861 size_t max_sym_count;
3862 file_ptr off;
3863 Elf_Internal_Sym elfsym;
3864 unsigned int i;
3865 Elf_Internal_Shdr *symtab_hdr;
3866 Elf_Internal_Shdr *symstrtab_hdr;
3867 struct elf_backend_data *bed = get_elf_backend_data (abfd);
3868 struct elf_outext_info eoinfo;
3869
3870 if (info->shared)
3871 abfd->flags |= DYNAMIC;
3872
3873 dynamic = elf_hash_table (info)->dynamic_sections_created;
3874 dynobj = elf_hash_table (info)->dynobj;
3875
3876 finfo.info = info;
3877 finfo.output_bfd = abfd;
3878 finfo.symstrtab = elf_stringtab_init ();
3879 if (finfo.symstrtab == NULL)
3880 return false;
3881
3882 if (! dynamic)
3883 {
3884 finfo.dynsym_sec = NULL;
3885 finfo.hash_sec = NULL;
3886 finfo.symver_sec = NULL;
3887 }
3888 else
3889 {
3890 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
3891 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
3892 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
3893 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
3894 /* Note that it is OK if symver_sec is NULL. */
3895 }
3896
3897 finfo.contents = NULL;
3898 finfo.external_relocs = NULL;
3899 finfo.internal_relocs = NULL;
3900 finfo.external_syms = NULL;
3901 finfo.internal_syms = NULL;
3902 finfo.indices = NULL;
3903 finfo.sections = NULL;
3904 finfo.symbuf = NULL;
3905 finfo.symbuf_count = 0;
3906
3907 /* Count up the number of relocations we will output for each output
3908 section, so that we know the sizes of the reloc sections. We
3909 also figure out some maximum sizes. */
3910 max_contents_size = 0;
3911 max_external_reloc_size = 0;
3912 max_internal_reloc_count = 0;
3913 max_sym_count = 0;
3914 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
3915 {
3916 o->reloc_count = 0;
3917
3918 for (p = o->link_order_head; p != NULL; p = p->next)
3919 {
3920 if (p->type == bfd_section_reloc_link_order
3921 || p->type == bfd_symbol_reloc_link_order)
3922 ++o->reloc_count;
3923 else if (p->type == bfd_indirect_link_order)
3924 {
3925 asection *sec;
3926
3927 sec = p->u.indirect.section;
3928
3929 /* Mark all sections which are to be included in the
3930 link. This will normally be every section. We need
3931 to do this so that we can identify any sections which
3932 the linker has decided to not include. */
3933 sec->linker_mark = true;
3934
3935 if (info->relocateable)
3936 o->reloc_count += sec->reloc_count;
3937
3938 if (sec->_raw_size > max_contents_size)
3939 max_contents_size = sec->_raw_size;
3940 if (sec->_cooked_size > max_contents_size)
3941 max_contents_size = sec->_cooked_size;
3942
3943 /* We are interested in just local symbols, not all
3944 symbols. */
3945 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
3946 && (sec->owner->flags & DYNAMIC) == 0)
3947 {
3948 size_t sym_count;
3949
3950 if (elf_bad_symtab (sec->owner))
3951 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
3952 / sizeof (Elf_External_Sym));
3953 else
3954 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
3955
3956 if (sym_count > max_sym_count)
3957 max_sym_count = sym_count;
3958
3959 if ((sec->flags & SEC_RELOC) != 0)
3960 {
3961 size_t ext_size;
3962
3963 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
3964 if (ext_size > max_external_reloc_size)
3965 max_external_reloc_size = ext_size;
3966 if (sec->reloc_count > max_internal_reloc_count)
3967 max_internal_reloc_count = sec->reloc_count;
3968 }
3969 }
3970 }
3971 }
3972
3973 if (o->reloc_count > 0)
3974 o->flags |= SEC_RELOC;
3975 else
3976 {
3977 /* Explicitly clear the SEC_RELOC flag. The linker tends to
3978 set it (this is probably a bug) and if it is set
3979 assign_section_numbers will create a reloc section. */
3980 o->flags &=~ SEC_RELOC;
3981 }
3982
3983 /* If the SEC_ALLOC flag is not set, force the section VMA to
3984 zero. This is done in elf_fake_sections as well, but forcing
3985 the VMA to 0 here will ensure that relocs against these
3986 sections are handled correctly. */
3987 if ((o->flags & SEC_ALLOC) == 0
3988 && ! o->user_set_vma)
3989 o->vma = 0;
3990 }
3991
3992 /* Figure out the file positions for everything but the symbol table
3993 and the relocs. We set symcount to force assign_section_numbers
3994 to create a symbol table. */
3995 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
3996 BFD_ASSERT (! abfd->output_has_begun);
3997 if (! _bfd_elf_compute_section_file_positions (abfd, info))
3998 goto error_return;
3999
4000 /* That created the reloc sections. Set their sizes, and assign
4001 them file positions, and allocate some buffers. */
4002 for (o = abfd->sections; o != NULL; o = o->next)
4003 {
4004 if ((o->flags & SEC_RELOC) != 0)
4005 {
4006 if (!elf_link_size_reloc_section (abfd,
4007 &elf_section_data (o)->rel_hdr,
4008 o))
4009 goto error_return;
4010
4011 if (elf_section_data (o)->rel_hdr2
4012 && !elf_link_size_reloc_section (abfd,
4013 elf_section_data (o)->rel_hdr2,
4014 o))
4015 goto error_return;
4016 }
4017 }
4018
4019 _bfd_elf_assign_file_positions_for_relocs (abfd);
4020
4021 /* We have now assigned file positions for all the sections except
4022 .symtab and .strtab. We start the .symtab section at the current
4023 file position, and write directly to it. We build the .strtab
4024 section in memory. */
4025 bfd_get_symcount (abfd) = 0;
4026 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4027 /* sh_name is set in prep_headers. */
4028 symtab_hdr->sh_type = SHT_SYMTAB;
4029 symtab_hdr->sh_flags = 0;
4030 symtab_hdr->sh_addr = 0;
4031 symtab_hdr->sh_size = 0;
4032 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4033 /* sh_link is set in assign_section_numbers. */
4034 /* sh_info is set below. */
4035 /* sh_offset is set just below. */
4036 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4037
4038 off = elf_tdata (abfd)->next_file_pos;
4039 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4040
4041 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4042 incorrect. We do not yet know the size of the .symtab section.
4043 We correct next_file_pos below, after we do know the size. */
4044
4045 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4046 continuously seeking to the right position in the file. */
4047 if (! info->keep_memory || max_sym_count < 20)
4048 finfo.symbuf_size = 20;
4049 else
4050 finfo.symbuf_size = max_sym_count;
4051 finfo.symbuf = ((Elf_External_Sym *)
4052 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4053 if (finfo.symbuf == NULL)
4054 goto error_return;
4055
4056 /* Start writing out the symbol table. The first symbol is always a
4057 dummy symbol. */
4058 if (info->strip != strip_all || info->relocateable)
4059 {
4060 elfsym.st_value = 0;
4061 elfsym.st_size = 0;
4062 elfsym.st_info = 0;
4063 elfsym.st_other = 0;
4064 elfsym.st_shndx = SHN_UNDEF;
4065 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4066 &elfsym, bfd_und_section_ptr))
4067 goto error_return;
4068 }
4069
4070 #if 0
4071 /* Some standard ELF linkers do this, but we don't because it causes
4072 bootstrap comparison failures. */
4073 /* Output a file symbol for the output file as the second symbol.
4074 We output this even if we are discarding local symbols, although
4075 I'm not sure if this is correct. */
4076 elfsym.st_value = 0;
4077 elfsym.st_size = 0;
4078 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4079 elfsym.st_other = 0;
4080 elfsym.st_shndx = SHN_ABS;
4081 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4082 &elfsym, bfd_abs_section_ptr))
4083 goto error_return;
4084 #endif
4085
4086 /* Output a symbol for each section. We output these even if we are
4087 discarding local symbols, since they are used for relocs. These
4088 symbols have no names. We store the index of each one in the
4089 index field of the section, so that we can find it again when
4090 outputting relocs. */
4091 if (info->strip != strip_all || info->relocateable)
4092 {
4093 elfsym.st_size = 0;
4094 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4095 elfsym.st_other = 0;
4096 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4097 {
4098 o = section_from_elf_index (abfd, i);
4099 if (o != NULL)
4100 o->target_index = bfd_get_symcount (abfd);
4101 elfsym.st_shndx = i;
4102 if (info->relocateable || o == NULL)
4103 elfsym.st_value = 0;
4104 else
4105 elfsym.st_value = o->vma;
4106 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4107 &elfsym, o))
4108 goto error_return;
4109 }
4110 }
4111
4112 /* Allocate some memory to hold information read in from the input
4113 files. */
4114 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4115 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4116 finfo.internal_relocs = ((Elf_Internal_Rela *)
4117 bfd_malloc (max_internal_reloc_count
4118 * sizeof (Elf_Internal_Rela)
4119 * bed->s->int_rels_per_ext_rel));
4120 finfo.external_syms = ((Elf_External_Sym *)
4121 bfd_malloc (max_sym_count
4122 * sizeof (Elf_External_Sym)));
4123 finfo.internal_syms = ((Elf_Internal_Sym *)
4124 bfd_malloc (max_sym_count
4125 * sizeof (Elf_Internal_Sym)));
4126 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4127 finfo.sections = ((asection **)
4128 bfd_malloc (max_sym_count * sizeof (asection *)));
4129 if ((finfo.contents == NULL && max_contents_size != 0)
4130 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4131 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4132 || (finfo.external_syms == NULL && max_sym_count != 0)
4133 || (finfo.internal_syms == NULL && max_sym_count != 0)
4134 || (finfo.indices == NULL && max_sym_count != 0)
4135 || (finfo.sections == NULL && max_sym_count != 0))
4136 goto error_return;
4137
4138 /* Since ELF permits relocations to be against local symbols, we
4139 must have the local symbols available when we do the relocations.
4140 Since we would rather only read the local symbols once, and we
4141 would rather not keep them in memory, we handle all the
4142 relocations for a single input file at the same time.
4143
4144 Unfortunately, there is no way to know the total number of local
4145 symbols until we have seen all of them, and the local symbol
4146 indices precede the global symbol indices. This means that when
4147 we are generating relocateable output, and we see a reloc against
4148 a global symbol, we can not know the symbol index until we have
4149 finished examining all the local symbols to see which ones we are
4150 going to output. To deal with this, we keep the relocations in
4151 memory, and don't output them until the end of the link. This is
4152 an unfortunate waste of memory, but I don't see a good way around
4153 it. Fortunately, it only happens when performing a relocateable
4154 link, which is not the common case. FIXME: If keep_memory is set
4155 we could write the relocs out and then read them again; I don't
4156 know how bad the memory loss will be. */
4157
4158 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4159 sub->output_has_begun = false;
4160 for (o = abfd->sections; o != NULL; o = o->next)
4161 {
4162 for (p = o->link_order_head; p != NULL; p = p->next)
4163 {
4164 if (p->type == bfd_indirect_link_order
4165 && (bfd_get_flavour (p->u.indirect.section->owner)
4166 == bfd_target_elf_flavour))
4167 {
4168 sub = p->u.indirect.section->owner;
4169 if (! sub->output_has_begun)
4170 {
4171 if (! elf_link_input_bfd (&finfo, sub))
4172 goto error_return;
4173 sub->output_has_begun = true;
4174 }
4175 }
4176 else if (p->type == bfd_section_reloc_link_order
4177 || p->type == bfd_symbol_reloc_link_order)
4178 {
4179 if (! elf_reloc_link_order (abfd, info, o, p))
4180 goto error_return;
4181 }
4182 else
4183 {
4184 if (! _bfd_default_link_order (abfd, info, o, p))
4185 goto error_return;
4186 }
4187 }
4188 }
4189
4190 /* That wrote out all the local symbols. Finish up the symbol table
4191 with the global symbols. */
4192
4193 if (info->strip != strip_all && info->shared)
4194 {
4195 /* Output any global symbols that got converted to local in a
4196 version script. We do this in a separate step since ELF
4197 requires all local symbols to appear prior to any global
4198 symbols. FIXME: We should only do this if some global
4199 symbols were, in fact, converted to become local. FIXME:
4200 Will this work correctly with the Irix 5 linker? */
4201 eoinfo.failed = false;
4202 eoinfo.finfo = &finfo;
4203 eoinfo.localsyms = true;
4204 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4205 (PTR) &eoinfo);
4206 if (eoinfo.failed)
4207 return false;
4208 }
4209
4210 /* The sh_info field records the index of the first non local symbol. */
4211 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4212
4213 if (dynamic)
4214 {
4215 Elf_Internal_Sym sym;
4216 Elf_External_Sym *dynsym =
4217 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4218 unsigned long last_local = 0;
4219
4220 /* Write out the section symbols for the output sections. */
4221 if (info->shared)
4222 {
4223 asection *s;
4224
4225 sym.st_size = 0;
4226 sym.st_name = 0;
4227 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4228 sym.st_other = 0;
4229
4230 for (s = abfd->sections; s != NULL; s = s->next)
4231 {
4232 int indx;
4233 indx = elf_section_data (s)->this_idx;
4234 BFD_ASSERT (indx > 0);
4235 sym.st_shndx = indx;
4236 sym.st_value = s->vma;
4237
4238 elf_swap_symbol_out (abfd, &sym,
4239 dynsym + elf_section_data (s)->dynindx);
4240 }
4241
4242 last_local = bfd_count_sections (abfd);
4243 }
4244
4245 /* Write out the local dynsyms. */
4246 if (elf_hash_table (info)->dynlocal)
4247 {
4248 struct elf_link_local_dynamic_entry *e;
4249 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4250 {
4251 asection *s;
4252
4253 /* Copy the internal symbol as is.
4254 Note that we saved a word of storage and overwrote
4255 the original st_name with the dynstr_index. */
4256 sym = e->isym;
4257
4258 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4259 {
4260 s = bfd_section_from_elf_index (e->input_bfd,
4261 e->isym.st_shndx);
4262
4263 sym.st_shndx =
4264 elf_section_data (s->output_section)->this_idx;
4265 sym.st_value = (s->output_section->vma
4266 + s->output_offset
4267 + e->isym.st_value);
4268 }
4269
4270 if (last_local < e->dynindx)
4271 last_local = e->dynindx;
4272
4273 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4274 }
4275 }
4276
4277 elf_section_data (finfo.dynsym_sec->output_section)
4278 ->this_hdr.sh_info = last_local + 1;
4279 }
4280
4281 /* We get the global symbols from the hash table. */
4282 eoinfo.failed = false;
4283 eoinfo.localsyms = false;
4284 eoinfo.finfo = &finfo;
4285 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4286 (PTR) &eoinfo);
4287 if (eoinfo.failed)
4288 return false;
4289
4290 /* If backend needs to output some symbols not present in the hash
4291 table, do it now. */
4292 if (bed->elf_backend_output_arch_syms)
4293 {
4294 if (! (*bed->elf_backend_output_arch_syms)
4295 (abfd, info, (PTR) &finfo,
4296 (boolean (*) PARAMS ((PTR, const char *,
4297 Elf_Internal_Sym *, asection *)))
4298 elf_link_output_sym))
4299 return false;
4300 }
4301
4302 /* Flush all symbols to the file. */
4303 if (! elf_link_flush_output_syms (&finfo))
4304 return false;
4305
4306 /* Now we know the size of the symtab section. */
4307 off += symtab_hdr->sh_size;
4308
4309 /* Finish up and write out the symbol string table (.strtab)
4310 section. */
4311 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4312 /* sh_name was set in prep_headers. */
4313 symstrtab_hdr->sh_type = SHT_STRTAB;
4314 symstrtab_hdr->sh_flags = 0;
4315 symstrtab_hdr->sh_addr = 0;
4316 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4317 symstrtab_hdr->sh_entsize = 0;
4318 symstrtab_hdr->sh_link = 0;
4319 symstrtab_hdr->sh_info = 0;
4320 /* sh_offset is set just below. */
4321 symstrtab_hdr->sh_addralign = 1;
4322
4323 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4324 elf_tdata (abfd)->next_file_pos = off;
4325
4326 if (bfd_get_symcount (abfd) > 0)
4327 {
4328 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4329 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4330 return false;
4331 }
4332
4333 /* Adjust the relocs to have the correct symbol indices. */
4334 for (o = abfd->sections; o != NULL; o = o->next)
4335 {
4336 if ((o->flags & SEC_RELOC) == 0)
4337 continue;
4338
4339 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4340 elf_section_data (o)->rel_count,
4341 elf_section_data (o)->rel_hashes);
4342 if (elf_section_data (o)->rel_hdr2 != NULL)
4343 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4344 elf_section_data (o)->rel_count2,
4345 (elf_section_data (o)->rel_hashes
4346 + elf_section_data (o)->rel_count));
4347
4348 /* Set the reloc_count field to 0 to prevent write_relocs from
4349 trying to swap the relocs out itself. */
4350 o->reloc_count = 0;
4351 }
4352
4353 /* If we are linking against a dynamic object, or generating a
4354 shared library, finish up the dynamic linking information. */
4355 if (dynamic)
4356 {
4357 Elf_External_Dyn *dyncon, *dynconend;
4358
4359 /* Fix up .dynamic entries. */
4360 o = bfd_get_section_by_name (dynobj, ".dynamic");
4361 BFD_ASSERT (o != NULL);
4362
4363 dyncon = (Elf_External_Dyn *) o->contents;
4364 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4365 for (; dyncon < dynconend; dyncon++)
4366 {
4367 Elf_Internal_Dyn dyn;
4368 const char *name;
4369 unsigned int type;
4370
4371 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4372
4373 switch (dyn.d_tag)
4374 {
4375 default:
4376 break;
4377 case DT_INIT:
4378 name = info->init_function;
4379 goto get_sym;
4380 case DT_FINI:
4381 name = info->fini_function;
4382 get_sym:
4383 {
4384 struct elf_link_hash_entry *h;
4385
4386 h = elf_link_hash_lookup (elf_hash_table (info), name,
4387 false, false, true);
4388 if (h != NULL
4389 && (h->root.type == bfd_link_hash_defined
4390 || h->root.type == bfd_link_hash_defweak))
4391 {
4392 dyn.d_un.d_val = h->root.u.def.value;
4393 o = h->root.u.def.section;
4394 if (o->output_section != NULL)
4395 dyn.d_un.d_val += (o->output_section->vma
4396 + o->output_offset);
4397 else
4398 {
4399 /* The symbol is imported from another shared
4400 library and does not apply to this one. */
4401 dyn.d_un.d_val = 0;
4402 }
4403
4404 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4405 }
4406 }
4407 break;
4408
4409 case DT_HASH:
4410 name = ".hash";
4411 goto get_vma;
4412 case DT_STRTAB:
4413 name = ".dynstr";
4414 goto get_vma;
4415 case DT_SYMTAB:
4416 name = ".dynsym";
4417 goto get_vma;
4418 case DT_VERDEF:
4419 name = ".gnu.version_d";
4420 goto get_vma;
4421 case DT_VERNEED:
4422 name = ".gnu.version_r";
4423 goto get_vma;
4424 case DT_VERSYM:
4425 name = ".gnu.version";
4426 get_vma:
4427 o = bfd_get_section_by_name (abfd, name);
4428 BFD_ASSERT (o != NULL);
4429 dyn.d_un.d_ptr = o->vma;
4430 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4431 break;
4432
4433 case DT_REL:
4434 case DT_RELA:
4435 case DT_RELSZ:
4436 case DT_RELASZ:
4437 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4438 type = SHT_REL;
4439 else
4440 type = SHT_RELA;
4441 dyn.d_un.d_val = 0;
4442 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4443 {
4444 Elf_Internal_Shdr *hdr;
4445
4446 hdr = elf_elfsections (abfd)[i];
4447 if (hdr->sh_type == type
4448 && (hdr->sh_flags & SHF_ALLOC) != 0)
4449 {
4450 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4451 dyn.d_un.d_val += hdr->sh_size;
4452 else
4453 {
4454 if (dyn.d_un.d_val == 0
4455 || hdr->sh_addr < dyn.d_un.d_val)
4456 dyn.d_un.d_val = hdr->sh_addr;
4457 }
4458 }
4459 }
4460 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4461 break;
4462 }
4463 }
4464 }
4465
4466 /* If we have created any dynamic sections, then output them. */
4467 if (dynobj != NULL)
4468 {
4469 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4470 goto error_return;
4471
4472 for (o = dynobj->sections; o != NULL; o = o->next)
4473 {
4474 if ((o->flags & SEC_HAS_CONTENTS) == 0
4475 || o->_raw_size == 0)
4476 continue;
4477 if ((o->flags & SEC_LINKER_CREATED) == 0)
4478 {
4479 /* At this point, we are only interested in sections
4480 created by elf_link_create_dynamic_sections. */
4481 continue;
4482 }
4483 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4484 != SHT_STRTAB)
4485 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4486 {
4487 if (! bfd_set_section_contents (abfd, o->output_section,
4488 o->contents, o->output_offset,
4489 o->_raw_size))
4490 goto error_return;
4491 }
4492 else
4493 {
4494 file_ptr off;
4495
4496 /* The contents of the .dynstr section are actually in a
4497 stringtab. */
4498 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4499 if (bfd_seek (abfd, off, SEEK_SET) != 0
4500 || ! _bfd_stringtab_emit (abfd,
4501 elf_hash_table (info)->dynstr))
4502 goto error_return;
4503 }
4504 }
4505 }
4506
4507 /* If we have optimized stabs strings, output them. */
4508 if (elf_hash_table (info)->stab_info != NULL)
4509 {
4510 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4511 goto error_return;
4512 }
4513
4514 if (finfo.symstrtab != NULL)
4515 _bfd_stringtab_free (finfo.symstrtab);
4516 if (finfo.contents != NULL)
4517 free (finfo.contents);
4518 if (finfo.external_relocs != NULL)
4519 free (finfo.external_relocs);
4520 if (finfo.internal_relocs != NULL)
4521 free (finfo.internal_relocs);
4522 if (finfo.external_syms != NULL)
4523 free (finfo.external_syms);
4524 if (finfo.internal_syms != NULL)
4525 free (finfo.internal_syms);
4526 if (finfo.indices != NULL)
4527 free (finfo.indices);
4528 if (finfo.sections != NULL)
4529 free (finfo.sections);
4530 if (finfo.symbuf != NULL)
4531 free (finfo.symbuf);
4532 for (o = abfd->sections; o != NULL; o = o->next)
4533 {
4534 if ((o->flags & SEC_RELOC) != 0
4535 && elf_section_data (o)->rel_hashes != NULL)
4536 free (elf_section_data (o)->rel_hashes);
4537 }
4538
4539 elf_tdata (abfd)->linker = true;
4540
4541 return true;
4542
4543 error_return:
4544 if (finfo.symstrtab != NULL)
4545 _bfd_stringtab_free (finfo.symstrtab);
4546 if (finfo.contents != NULL)
4547 free (finfo.contents);
4548 if (finfo.external_relocs != NULL)
4549 free (finfo.external_relocs);
4550 if (finfo.internal_relocs != NULL)
4551 free (finfo.internal_relocs);
4552 if (finfo.external_syms != NULL)
4553 free (finfo.external_syms);
4554 if (finfo.internal_syms != NULL)
4555 free (finfo.internal_syms);
4556 if (finfo.indices != NULL)
4557 free (finfo.indices);
4558 if (finfo.sections != NULL)
4559 free (finfo.sections);
4560 if (finfo.symbuf != NULL)
4561 free (finfo.symbuf);
4562 for (o = abfd->sections; o != NULL; o = o->next)
4563 {
4564 if ((o->flags & SEC_RELOC) != 0
4565 && elf_section_data (o)->rel_hashes != NULL)
4566 free (elf_section_data (o)->rel_hashes);
4567 }
4568
4569 return false;
4570 }
4571
4572 /* Add a symbol to the output symbol table. */
4573
4574 static boolean
4575 elf_link_output_sym (finfo, name, elfsym, input_sec)
4576 struct elf_final_link_info *finfo;
4577 const char *name;
4578 Elf_Internal_Sym *elfsym;
4579 asection *input_sec;
4580 {
4581 boolean (*output_symbol_hook) PARAMS ((bfd *,
4582 struct bfd_link_info *info,
4583 const char *,
4584 Elf_Internal_Sym *,
4585 asection *));
4586
4587 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4588 elf_backend_link_output_symbol_hook;
4589 if (output_symbol_hook != NULL)
4590 {
4591 if (! ((*output_symbol_hook)
4592 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4593 return false;
4594 }
4595
4596 if (name == (const char *) NULL || *name == '\0')
4597 elfsym->st_name = 0;
4598 else if (input_sec->flags & SEC_EXCLUDE)
4599 elfsym->st_name = 0;
4600 else
4601 {
4602 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
4603 name, true,
4604 false);
4605 if (elfsym->st_name == (unsigned long) -1)
4606 return false;
4607 }
4608
4609 if (finfo->symbuf_count >= finfo->symbuf_size)
4610 {
4611 if (! elf_link_flush_output_syms (finfo))
4612 return false;
4613 }
4614
4615 elf_swap_symbol_out (finfo->output_bfd, elfsym,
4616 (PTR) (finfo->symbuf + finfo->symbuf_count));
4617 ++finfo->symbuf_count;
4618
4619 ++ bfd_get_symcount (finfo->output_bfd);
4620
4621 return true;
4622 }
4623
4624 /* Flush the output symbols to the file. */
4625
4626 static boolean
4627 elf_link_flush_output_syms (finfo)
4628 struct elf_final_link_info *finfo;
4629 {
4630 if (finfo->symbuf_count > 0)
4631 {
4632 Elf_Internal_Shdr *symtab;
4633
4634 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
4635
4636 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
4637 SEEK_SET) != 0
4638 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
4639 sizeof (Elf_External_Sym), finfo->output_bfd)
4640 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
4641 return false;
4642
4643 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
4644
4645 finfo->symbuf_count = 0;
4646 }
4647
4648 return true;
4649 }
4650
4651 /* Add an external symbol to the symbol table. This is called from
4652 the hash table traversal routine. When generating a shared object,
4653 we go through the symbol table twice. The first time we output
4654 anything that might have been forced to local scope in a version
4655 script. The second time we output the symbols that are still
4656 global symbols. */
4657
4658 static boolean
4659 elf_link_output_extsym (h, data)
4660 struct elf_link_hash_entry *h;
4661 PTR data;
4662 {
4663 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
4664 struct elf_final_link_info *finfo = eoinfo->finfo;
4665 boolean strip;
4666 Elf_Internal_Sym sym;
4667 asection *input_sec;
4668
4669 /* Decide whether to output this symbol in this pass. */
4670 if (eoinfo->localsyms)
4671 {
4672 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
4673 return true;
4674 }
4675 else
4676 {
4677 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4678 return true;
4679 }
4680
4681 /* If we are not creating a shared library, and this symbol is
4682 referenced by a shared library but is not defined anywhere, then
4683 warn that it is undefined. If we do not do this, the runtime
4684 linker will complain that the symbol is undefined when the
4685 program is run. We don't have to worry about symbols that are
4686 referenced by regular files, because we will already have issued
4687 warnings for them. */
4688 if (! finfo->info->relocateable
4689 && ! (finfo->info->shared
4690 && !finfo->info->no_undefined)
4691 && h->root.type == bfd_link_hash_undefined
4692 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
4693 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4694 {
4695 if (! ((*finfo->info->callbacks->undefined_symbol)
4696 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
4697 (asection *) NULL, 0)))
4698 {
4699 eoinfo->failed = true;
4700 return false;
4701 }
4702 }
4703
4704 /* We don't want to output symbols that have never been mentioned by
4705 a regular file, or that we have been told to strip. However, if
4706 h->indx is set to -2, the symbol is used by a reloc and we must
4707 output it. */
4708 if (h->indx == -2)
4709 strip = false;
4710 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
4711 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
4712 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
4713 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
4714 strip = true;
4715 else if (finfo->info->strip == strip_all
4716 || (finfo->info->strip == strip_some
4717 && bfd_hash_lookup (finfo->info->keep_hash,
4718 h->root.root.string,
4719 false, false) == NULL))
4720 strip = true;
4721 else
4722 strip = false;
4723
4724 /* If we're stripping it, and it's not a dynamic symbol, there's
4725 nothing else to do. */
4726 if (strip && h->dynindx == -1)
4727 return true;
4728
4729 sym.st_value = 0;
4730 sym.st_size = h->size;
4731 sym.st_other = h->other;
4732 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4733 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
4734 else if (h->root.type == bfd_link_hash_undefweak
4735 || h->root.type == bfd_link_hash_defweak)
4736 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
4737 else
4738 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
4739
4740 switch (h->root.type)
4741 {
4742 default:
4743 case bfd_link_hash_new:
4744 abort ();
4745 return false;
4746
4747 case bfd_link_hash_undefined:
4748 input_sec = bfd_und_section_ptr;
4749 sym.st_shndx = SHN_UNDEF;
4750 break;
4751
4752 case bfd_link_hash_undefweak:
4753 input_sec = bfd_und_section_ptr;
4754 sym.st_shndx = SHN_UNDEF;
4755 break;
4756
4757 case bfd_link_hash_defined:
4758 case bfd_link_hash_defweak:
4759 {
4760 input_sec = h->root.u.def.section;
4761 if (input_sec->output_section != NULL)
4762 {
4763 sym.st_shndx =
4764 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
4765 input_sec->output_section);
4766 if (sym.st_shndx == (unsigned short) -1)
4767 {
4768 (*_bfd_error_handler)
4769 (_("%s: could not find output section %s for input section %s"),
4770 bfd_get_filename (finfo->output_bfd),
4771 input_sec->output_section->name,
4772 input_sec->name);
4773 eoinfo->failed = true;
4774 return false;
4775 }
4776
4777 /* ELF symbols in relocateable files are section relative,
4778 but in nonrelocateable files they are virtual
4779 addresses. */
4780 sym.st_value = h->root.u.def.value + input_sec->output_offset;
4781 if (! finfo->info->relocateable)
4782 sym.st_value += input_sec->output_section->vma;
4783 }
4784 else
4785 {
4786 BFD_ASSERT (input_sec->owner == NULL
4787 || (input_sec->owner->flags & DYNAMIC) != 0);
4788 sym.st_shndx = SHN_UNDEF;
4789 input_sec = bfd_und_section_ptr;
4790 }
4791 }
4792 break;
4793
4794 case bfd_link_hash_common:
4795 input_sec = h->root.u.c.p->section;
4796 sym.st_shndx = SHN_COMMON;
4797 sym.st_value = 1 << h->root.u.c.p->alignment_power;
4798 break;
4799
4800 case bfd_link_hash_indirect:
4801 /* These symbols are created by symbol versioning. They point
4802 to the decorated version of the name. For example, if the
4803 symbol foo@@GNU_1.2 is the default, which should be used when
4804 foo is used with no version, then we add an indirect symbol
4805 foo which points to foo@@GNU_1.2. We ignore these symbols,
4806 since the indirected symbol is already in the hash table. If
4807 the indirect symbol is non-ELF, fall through and output it. */
4808 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) == 0)
4809 return true;
4810
4811 /* Fall through. */
4812 case bfd_link_hash_warning:
4813 /* We can't represent these symbols in ELF, although a warning
4814 symbol may have come from a .gnu.warning.SYMBOL section. We
4815 just put the target symbol in the hash table. If the target
4816 symbol does not really exist, don't do anything. */
4817 if (h->root.u.i.link->type == bfd_link_hash_new)
4818 return true;
4819 return (elf_link_output_extsym
4820 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
4821 }
4822
4823 /* Give the processor backend a chance to tweak the symbol value,
4824 and also to finish up anything that needs to be done for this
4825 symbol. */
4826 if ((h->dynindx != -1
4827 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
4828 && elf_hash_table (finfo->info)->dynamic_sections_created)
4829 {
4830 struct elf_backend_data *bed;
4831
4832 bed = get_elf_backend_data (finfo->output_bfd);
4833 if (! ((*bed->elf_backend_finish_dynamic_symbol)
4834 (finfo->output_bfd, finfo->info, h, &sym)))
4835 {
4836 eoinfo->failed = true;
4837 return false;
4838 }
4839 }
4840
4841 /* If we are marking the symbol as undefined, and there are no
4842 non-weak references to this symbol from a regular object, then
4843 mark the symbol as weak undefined; if there are non-weak
4844 references, mark the symbol as strong. We can't do this earlier,
4845 because it might not be marked as undefined until the
4846 finish_dynamic_symbol routine gets through with it. */
4847 if (sym.st_shndx == SHN_UNDEF
4848 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
4849 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
4850 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
4851 {
4852 int bindtype;
4853
4854 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
4855 bindtype = STB_GLOBAL;
4856 else
4857 bindtype = STB_WEAK;
4858 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
4859 }
4860
4861 /* If this symbol should be put in the .dynsym section, then put it
4862 there now. We have already know the symbol index. We also fill
4863 in the entry in the .hash section. */
4864 if (h->dynindx != -1
4865 && elf_hash_table (finfo->info)->dynamic_sections_created)
4866 {
4867 size_t bucketcount;
4868 size_t bucket;
4869 size_t hash_entry_size;
4870 bfd_byte *bucketpos;
4871 bfd_vma chain;
4872
4873 sym.st_name = h->dynstr_index;
4874
4875 elf_swap_symbol_out (finfo->output_bfd, &sym,
4876 (PTR) (((Elf_External_Sym *)
4877 finfo->dynsym_sec->contents)
4878 + h->dynindx));
4879
4880 bucketcount = elf_hash_table (finfo->info)->bucketcount;
4881 bucket = h->elf_hash_value % bucketcount;
4882 hash_entry_size
4883 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
4884 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
4885 + (bucket + 2) * hash_entry_size);
4886 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
4887 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
4888 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
4889 ((bfd_byte *) finfo->hash_sec->contents
4890 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
4891
4892 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
4893 {
4894 Elf_Internal_Versym iversym;
4895
4896 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
4897 {
4898 if (h->verinfo.verdef == NULL)
4899 iversym.vs_vers = 0;
4900 else
4901 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
4902 }
4903 else
4904 {
4905 if (h->verinfo.vertree == NULL)
4906 iversym.vs_vers = 1;
4907 else
4908 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
4909 }
4910
4911 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
4912 iversym.vs_vers |= VERSYM_HIDDEN;
4913
4914 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
4915 (((Elf_External_Versym *)
4916 finfo->symver_sec->contents)
4917 + h->dynindx));
4918 }
4919 }
4920
4921 /* If we're stripping it, then it was just a dynamic symbol, and
4922 there's nothing else to do. */
4923 if (strip)
4924 return true;
4925
4926 h->indx = bfd_get_symcount (finfo->output_bfd);
4927
4928 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
4929 {
4930 eoinfo->failed = true;
4931 return false;
4932 }
4933
4934 return true;
4935 }
4936
4937 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
4938 originated from the section given by INPUT_REL_HDR) to the
4939 OUTPUT_BFD. */
4940
4941 static void
4942 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
4943 internal_relocs)
4944 bfd *output_bfd;
4945 asection *input_section;
4946 Elf_Internal_Shdr *input_rel_hdr;
4947 Elf_Internal_Rela *internal_relocs;
4948 {
4949 Elf_Internal_Rela *irela;
4950 Elf_Internal_Rela *irelaend;
4951 Elf_Internal_Shdr *output_rel_hdr;
4952 asection *output_section;
4953 unsigned int *rel_countp = NULL;
4954
4955 output_section = input_section->output_section;
4956 output_rel_hdr = NULL;
4957
4958 if (elf_section_data (output_section)->rel_hdr.sh_entsize
4959 == input_rel_hdr->sh_entsize)
4960 {
4961 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
4962 rel_countp = &elf_section_data (output_section)->rel_count;
4963 }
4964 else if (elf_section_data (output_section)->rel_hdr2
4965 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
4966 == input_rel_hdr->sh_entsize))
4967 {
4968 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
4969 rel_countp = &elf_section_data (output_section)->rel_count2;
4970 }
4971
4972 BFD_ASSERT (output_rel_hdr != NULL);
4973
4974 irela = internal_relocs;
4975 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
4976 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4977 {
4978 Elf_External_Rel *erel;
4979
4980 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
4981 for (; irela < irelaend; irela++, erel++)
4982 {
4983 Elf_Internal_Rel irel;
4984
4985 irel.r_offset = irela->r_offset;
4986 irel.r_info = irela->r_info;
4987 BFD_ASSERT (irela->r_addend == 0);
4988 elf_swap_reloc_out (output_bfd, &irel, erel);
4989 }
4990 }
4991 else
4992 {
4993 Elf_External_Rela *erela;
4994
4995 BFD_ASSERT (input_rel_hdr->sh_entsize
4996 == sizeof (Elf_External_Rela));
4997 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
4998 for (; irela < irelaend; irela++, erela++)
4999 elf_swap_reloca_out (output_bfd, irela, erela);
5000 }
5001
5002 /* Bump the counter, so that we know where to add the next set of
5003 relocations. */
5004 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5005 }
5006
5007 /* Link an input file into the linker output file. This function
5008 handles all the sections and relocations of the input file at once.
5009 This is so that we only have to read the local symbols once, and
5010 don't have to keep them in memory. */
5011
5012 static boolean
5013 elf_link_input_bfd (finfo, input_bfd)
5014 struct elf_final_link_info *finfo;
5015 bfd *input_bfd;
5016 {
5017 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5018 bfd *, asection *, bfd_byte *,
5019 Elf_Internal_Rela *,
5020 Elf_Internal_Sym *, asection **));
5021 bfd *output_bfd;
5022 Elf_Internal_Shdr *symtab_hdr;
5023 size_t locsymcount;
5024 size_t extsymoff;
5025 Elf_External_Sym *external_syms;
5026 Elf_External_Sym *esym;
5027 Elf_External_Sym *esymend;
5028 Elf_Internal_Sym *isym;
5029 long *pindex;
5030 asection **ppsection;
5031 asection *o;
5032 struct elf_backend_data *bed;
5033
5034 output_bfd = finfo->output_bfd;
5035 bed = get_elf_backend_data (output_bfd);
5036 relocate_section = bed->elf_backend_relocate_section;
5037
5038 /* If this is a dynamic object, we don't want to do anything here:
5039 we don't want the local symbols, and we don't want the section
5040 contents. */
5041 if ((input_bfd->flags & DYNAMIC) != 0)
5042 return true;
5043
5044 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5045 if (elf_bad_symtab (input_bfd))
5046 {
5047 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5048 extsymoff = 0;
5049 }
5050 else
5051 {
5052 locsymcount = symtab_hdr->sh_info;
5053 extsymoff = symtab_hdr->sh_info;
5054 }
5055
5056 /* Read the local symbols. */
5057 if (symtab_hdr->contents != NULL)
5058 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5059 else if (locsymcount == 0)
5060 external_syms = NULL;
5061 else
5062 {
5063 external_syms = finfo->external_syms;
5064 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5065 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5066 locsymcount, input_bfd)
5067 != locsymcount * sizeof (Elf_External_Sym)))
5068 return false;
5069 }
5070
5071 /* Swap in the local symbols and write out the ones which we know
5072 are going into the output file. */
5073 esym = external_syms;
5074 esymend = esym + locsymcount;
5075 isym = finfo->internal_syms;
5076 pindex = finfo->indices;
5077 ppsection = finfo->sections;
5078 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5079 {
5080 asection *isec;
5081 const char *name;
5082 Elf_Internal_Sym osym;
5083
5084 elf_swap_symbol_in (input_bfd, esym, isym);
5085 *pindex = -1;
5086
5087 if (elf_bad_symtab (input_bfd))
5088 {
5089 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5090 {
5091 *ppsection = NULL;
5092 continue;
5093 }
5094 }
5095
5096 if (isym->st_shndx == SHN_UNDEF)
5097 isec = bfd_und_section_ptr;
5098 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5099 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5100 else if (isym->st_shndx == SHN_ABS)
5101 isec = bfd_abs_section_ptr;
5102 else if (isym->st_shndx == SHN_COMMON)
5103 isec = bfd_com_section_ptr;
5104 else
5105 {
5106 /* Who knows? */
5107 isec = NULL;
5108 }
5109
5110 *ppsection = isec;
5111
5112 /* Don't output the first, undefined, symbol. */
5113 if (esym == external_syms)
5114 continue;
5115
5116 /* If we are stripping all symbols, we don't want to output this
5117 one. */
5118 if (finfo->info->strip == strip_all)
5119 continue;
5120
5121 /* We never output section symbols. Instead, we use the section
5122 symbol of the corresponding section in the output file. */
5123 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5124 continue;
5125
5126 /* If we are discarding all local symbols, we don't want to
5127 output this one. If we are generating a relocateable output
5128 file, then some of the local symbols may be required by
5129 relocs; we output them below as we discover that they are
5130 needed. */
5131 if (finfo->info->discard == discard_all)
5132 continue;
5133
5134 /* If this symbol is defined in a section which we are
5135 discarding, we don't need to keep it, but note that
5136 linker_mark is only reliable for sections that have contents.
5137 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5138 as well as linker_mark. */
5139 if (isym->st_shndx > 0
5140 && isym->st_shndx < SHN_LORESERVE
5141 && isec != NULL
5142 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5143 || (! finfo->info->relocateable
5144 && (isec->flags & SEC_EXCLUDE) != 0)))
5145 continue;
5146
5147 /* Get the name of the symbol. */
5148 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5149 isym->st_name);
5150 if (name == NULL)
5151 return false;
5152
5153 /* See if we are discarding symbols with this name. */
5154 if ((finfo->info->strip == strip_some
5155 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5156 == NULL))
5157 || (finfo->info->discard == discard_l
5158 && bfd_is_local_label_name (input_bfd, name)))
5159 continue;
5160
5161 /* If we get here, we are going to output this symbol. */
5162
5163 osym = *isym;
5164
5165 /* Adjust the section index for the output file. */
5166 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5167 isec->output_section);
5168 if (osym.st_shndx == (unsigned short) -1)
5169 return false;
5170
5171 *pindex = bfd_get_symcount (output_bfd);
5172
5173 /* ELF symbols in relocateable files are section relative, but
5174 in executable files they are virtual addresses. Note that
5175 this code assumes that all ELF sections have an associated
5176 BFD section with a reasonable value for output_offset; below
5177 we assume that they also have a reasonable value for
5178 output_section. Any special sections must be set up to meet
5179 these requirements. */
5180 osym.st_value += isec->output_offset;
5181 if (! finfo->info->relocateable)
5182 osym.st_value += isec->output_section->vma;
5183
5184 if (! elf_link_output_sym (finfo, name, &osym, isec))
5185 return false;
5186 }
5187
5188 /* Relocate the contents of each section. */
5189 for (o = input_bfd->sections; o != NULL; o = o->next)
5190 {
5191 bfd_byte *contents;
5192
5193 if (! o->linker_mark)
5194 {
5195 /* This section was omitted from the link. */
5196 continue;
5197 }
5198
5199 if ((o->flags & SEC_HAS_CONTENTS) == 0
5200 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5201 continue;
5202
5203 if ((o->flags & SEC_LINKER_CREATED) != 0)
5204 {
5205 /* Section was created by elf_link_create_dynamic_sections
5206 or somesuch. */
5207 continue;
5208 }
5209
5210 /* Get the contents of the section. They have been cached by a
5211 relaxation routine. Note that o is a section in an input
5212 file, so the contents field will not have been set by any of
5213 the routines which work on output files. */
5214 if (elf_section_data (o)->this_hdr.contents != NULL)
5215 contents = elf_section_data (o)->this_hdr.contents;
5216 else
5217 {
5218 contents = finfo->contents;
5219 if (! bfd_get_section_contents (input_bfd, o, contents,
5220 (file_ptr) 0, o->_raw_size))
5221 return false;
5222 }
5223
5224 if ((o->flags & SEC_RELOC) != 0)
5225 {
5226 Elf_Internal_Rela *internal_relocs;
5227
5228 /* Get the swapped relocs. */
5229 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5230 (input_bfd, o, finfo->external_relocs,
5231 finfo->internal_relocs, false));
5232 if (internal_relocs == NULL
5233 && o->reloc_count > 0)
5234 return false;
5235
5236 /* Relocate the section by invoking a back end routine.
5237
5238 The back end routine is responsible for adjusting the
5239 section contents as necessary, and (if using Rela relocs
5240 and generating a relocateable output file) adjusting the
5241 reloc addend as necessary.
5242
5243 The back end routine does not have to worry about setting
5244 the reloc address or the reloc symbol index.
5245
5246 The back end routine is given a pointer to the swapped in
5247 internal symbols, and can access the hash table entries
5248 for the external symbols via elf_sym_hashes (input_bfd).
5249
5250 When generating relocateable output, the back end routine
5251 must handle STB_LOCAL/STT_SECTION symbols specially. The
5252 output symbol is going to be a section symbol
5253 corresponding to the output section, which will require
5254 the addend to be adjusted. */
5255
5256 if (! (*relocate_section) (output_bfd, finfo->info,
5257 input_bfd, o, contents,
5258 internal_relocs,
5259 finfo->internal_syms,
5260 finfo->sections))
5261 return false;
5262
5263 if (finfo->info->relocateable)
5264 {
5265 Elf_Internal_Rela *irela;
5266 Elf_Internal_Rela *irelaend;
5267 struct elf_link_hash_entry **rel_hash;
5268 Elf_Internal_Shdr *input_rel_hdr;
5269
5270 /* Adjust the reloc addresses and symbol indices. */
5271
5272 irela = internal_relocs;
5273 irelaend =
5274 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5275 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5276 + elf_section_data (o->output_section)->rel_count
5277 + elf_section_data (o->output_section)->rel_count2);
5278 for (; irela < irelaend; irela++, rel_hash++)
5279 {
5280 unsigned long r_symndx;
5281 Elf_Internal_Sym *isym;
5282 asection *sec;
5283
5284 irela->r_offset += o->output_offset;
5285
5286 r_symndx = ELF_R_SYM (irela->r_info);
5287
5288 if (r_symndx == 0)
5289 continue;
5290
5291 if (r_symndx >= locsymcount
5292 || (elf_bad_symtab (input_bfd)
5293 && finfo->sections[r_symndx] == NULL))
5294 {
5295 struct elf_link_hash_entry *rh;
5296 long indx;
5297
5298 /* This is a reloc against a global symbol. We
5299 have not yet output all the local symbols, so
5300 we do not know the symbol index of any global
5301 symbol. We set the rel_hash entry for this
5302 reloc to point to the global hash table entry
5303 for this symbol. The symbol index is then
5304 set at the end of elf_bfd_final_link. */
5305 indx = r_symndx - extsymoff;
5306 rh = elf_sym_hashes (input_bfd)[indx];
5307 while (rh->root.type == bfd_link_hash_indirect
5308 || rh->root.type == bfd_link_hash_warning)
5309 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5310
5311 /* Setting the index to -2 tells
5312 elf_link_output_extsym that this symbol is
5313 used by a reloc. */
5314 BFD_ASSERT (rh->indx < 0);
5315 rh->indx = -2;
5316
5317 *rel_hash = rh;
5318
5319 continue;
5320 }
5321
5322 /* This is a reloc against a local symbol. */
5323
5324 *rel_hash = NULL;
5325 isym = finfo->internal_syms + r_symndx;
5326 sec = finfo->sections[r_symndx];
5327 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5328 {
5329 /* I suppose the backend ought to fill in the
5330 section of any STT_SECTION symbol against a
5331 processor specific section. If we have
5332 discarded a section, the output_section will
5333 be the absolute section. */
5334 if (sec != NULL
5335 && (bfd_is_abs_section (sec)
5336 || (sec->output_section != NULL
5337 && bfd_is_abs_section (sec->output_section))))
5338 r_symndx = 0;
5339 else if (sec == NULL || sec->owner == NULL)
5340 {
5341 bfd_set_error (bfd_error_bad_value);
5342 return false;
5343 }
5344 else
5345 {
5346 r_symndx = sec->output_section->target_index;
5347 BFD_ASSERT (r_symndx != 0);
5348 }
5349 }
5350 else
5351 {
5352 if (finfo->indices[r_symndx] == -1)
5353 {
5354 unsigned long link;
5355 const char *name;
5356 asection *osec;
5357
5358 if (finfo->info->strip == strip_all)
5359 {
5360 /* You can't do ld -r -s. */
5361 bfd_set_error (bfd_error_invalid_operation);
5362 return false;
5363 }
5364
5365 /* This symbol was skipped earlier, but
5366 since it is needed by a reloc, we
5367 must output it now. */
5368 link = symtab_hdr->sh_link;
5369 name = bfd_elf_string_from_elf_section (input_bfd,
5370 link,
5371 isym->st_name);
5372 if (name == NULL)
5373 return false;
5374
5375 osec = sec->output_section;
5376 isym->st_shndx =
5377 _bfd_elf_section_from_bfd_section (output_bfd,
5378 osec);
5379 if (isym->st_shndx == (unsigned short) -1)
5380 return false;
5381
5382 isym->st_value += sec->output_offset;
5383 if (! finfo->info->relocateable)
5384 isym->st_value += osec->vma;
5385
5386 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5387
5388 if (! elf_link_output_sym (finfo, name, isym, sec))
5389 return false;
5390 }
5391
5392 r_symndx = finfo->indices[r_symndx];
5393 }
5394
5395 irela->r_info = ELF_R_INFO (r_symndx,
5396 ELF_R_TYPE (irela->r_info));
5397 }
5398
5399 /* Swap out the relocs. */
5400 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5401 elf_link_output_relocs (output_bfd, o,
5402 input_rel_hdr,
5403 internal_relocs);
5404 internal_relocs
5405 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5406 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5407 if (input_rel_hdr)
5408 elf_link_output_relocs (output_bfd, o,
5409 input_rel_hdr,
5410 internal_relocs);
5411 }
5412 }
5413
5414 /* Write out the modified section contents. */
5415 if (elf_section_data (o)->stab_info == NULL)
5416 {
5417 if (! (o->flags & SEC_EXCLUDE) &&
5418 ! bfd_set_section_contents (output_bfd, o->output_section,
5419 contents, o->output_offset,
5420 (o->_cooked_size != 0
5421 ? o->_cooked_size
5422 : o->_raw_size)))
5423 return false;
5424 }
5425 else
5426 {
5427 if (! (_bfd_write_section_stabs
5428 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5429 o, &elf_section_data (o)->stab_info, contents)))
5430 return false;
5431 }
5432 }
5433
5434 return true;
5435 }
5436
5437 /* Generate a reloc when linking an ELF file. This is a reloc
5438 requested by the linker, and does come from any input file. This
5439 is used to build constructor and destructor tables when linking
5440 with -Ur. */
5441
5442 static boolean
5443 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5444 bfd *output_bfd;
5445 struct bfd_link_info *info;
5446 asection *output_section;
5447 struct bfd_link_order *link_order;
5448 {
5449 reloc_howto_type *howto;
5450 long indx;
5451 bfd_vma offset;
5452 bfd_vma addend;
5453 struct elf_link_hash_entry **rel_hash_ptr;
5454 Elf_Internal_Shdr *rel_hdr;
5455
5456 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5457 if (howto == NULL)
5458 {
5459 bfd_set_error (bfd_error_bad_value);
5460 return false;
5461 }
5462
5463 addend = link_order->u.reloc.p->addend;
5464
5465 /* Figure out the symbol index. */
5466 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5467 + elf_section_data (output_section)->rel_count
5468 + elf_section_data (output_section)->rel_count2);
5469 if (link_order->type == bfd_section_reloc_link_order)
5470 {
5471 indx = link_order->u.reloc.p->u.section->target_index;
5472 BFD_ASSERT (indx != 0);
5473 *rel_hash_ptr = NULL;
5474 }
5475 else
5476 {
5477 struct elf_link_hash_entry *h;
5478
5479 /* Treat a reloc against a defined symbol as though it were
5480 actually against the section. */
5481 h = ((struct elf_link_hash_entry *)
5482 bfd_wrapped_link_hash_lookup (output_bfd, info,
5483 link_order->u.reloc.p->u.name,
5484 false, false, true));
5485 if (h != NULL
5486 && (h->root.type == bfd_link_hash_defined
5487 || h->root.type == bfd_link_hash_defweak))
5488 {
5489 asection *section;
5490
5491 section = h->root.u.def.section;
5492 indx = section->output_section->target_index;
5493 *rel_hash_ptr = NULL;
5494 /* It seems that we ought to add the symbol value to the
5495 addend here, but in practice it has already been added
5496 because it was passed to constructor_callback. */
5497 addend += section->output_section->vma + section->output_offset;
5498 }
5499 else if (h != NULL)
5500 {
5501 /* Setting the index to -2 tells elf_link_output_extsym that
5502 this symbol is used by a reloc. */
5503 h->indx = -2;
5504 *rel_hash_ptr = h;
5505 indx = 0;
5506 }
5507 else
5508 {
5509 if (! ((*info->callbacks->unattached_reloc)
5510 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5511 (asection *) NULL, (bfd_vma) 0)))
5512 return false;
5513 indx = 0;
5514 }
5515 }
5516
5517 /* If this is an inplace reloc, we must write the addend into the
5518 object file. */
5519 if (howto->partial_inplace && addend != 0)
5520 {
5521 bfd_size_type size;
5522 bfd_reloc_status_type rstat;
5523 bfd_byte *buf;
5524 boolean ok;
5525
5526 size = bfd_get_reloc_size (howto);
5527 buf = (bfd_byte *) bfd_zmalloc (size);
5528 if (buf == (bfd_byte *) NULL)
5529 return false;
5530 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5531 switch (rstat)
5532 {
5533 case bfd_reloc_ok:
5534 break;
5535 default:
5536 case bfd_reloc_outofrange:
5537 abort ();
5538 case bfd_reloc_overflow:
5539 if (! ((*info->callbacks->reloc_overflow)
5540 (info,
5541 (link_order->type == bfd_section_reloc_link_order
5542 ? bfd_section_name (output_bfd,
5543 link_order->u.reloc.p->u.section)
5544 : link_order->u.reloc.p->u.name),
5545 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5546 (bfd_vma) 0)))
5547 {
5548 free (buf);
5549 return false;
5550 }
5551 break;
5552 }
5553 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5554 (file_ptr) link_order->offset, size);
5555 free (buf);
5556 if (! ok)
5557 return false;
5558 }
5559
5560 /* The address of a reloc is relative to the section in a
5561 relocateable file, and is a virtual address in an executable
5562 file. */
5563 offset = link_order->offset;
5564 if (! info->relocateable)
5565 offset += output_section->vma;
5566
5567 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5568
5569 if (rel_hdr->sh_type == SHT_REL)
5570 {
5571 Elf_Internal_Rel irel;
5572 Elf_External_Rel *erel;
5573
5574 irel.r_offset = offset;
5575 irel.r_info = ELF_R_INFO (indx, howto->type);
5576 erel = ((Elf_External_Rel *) rel_hdr->contents
5577 + elf_section_data (output_section)->rel_count);
5578 elf_swap_reloc_out (output_bfd, &irel, erel);
5579 }
5580 else
5581 {
5582 Elf_Internal_Rela irela;
5583 Elf_External_Rela *erela;
5584
5585 irela.r_offset = offset;
5586 irela.r_info = ELF_R_INFO (indx, howto->type);
5587 irela.r_addend = addend;
5588 erela = ((Elf_External_Rela *) rel_hdr->contents
5589 + elf_section_data (output_section)->rel_count);
5590 elf_swap_reloca_out (output_bfd, &irela, erela);
5591 }
5592
5593 ++elf_section_data (output_section)->rel_count;
5594
5595 return true;
5596 }
5597
5598 \f
5599 /* Allocate a pointer to live in a linker created section. */
5600
5601 boolean
5602 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
5603 bfd *abfd;
5604 struct bfd_link_info *info;
5605 elf_linker_section_t *lsect;
5606 struct elf_link_hash_entry *h;
5607 const Elf_Internal_Rela *rel;
5608 {
5609 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
5610 elf_linker_section_pointers_t *linker_section_ptr;
5611 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
5612
5613 BFD_ASSERT (lsect != NULL);
5614
5615 /* Is this a global symbol? */
5616 if (h != NULL)
5617 {
5618 /* Has this symbol already been allocated, if so, our work is done */
5619 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5620 rel->r_addend,
5621 lsect->which))
5622 return true;
5623
5624 ptr_linker_section_ptr = &h->linker_section_pointer;
5625 /* Make sure this symbol is output as a dynamic symbol. */
5626 if (h->dynindx == -1)
5627 {
5628 if (! elf_link_record_dynamic_symbol (info, h))
5629 return false;
5630 }
5631
5632 if (lsect->rel_section)
5633 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5634 }
5635
5636 else /* Allocation of a pointer to a local symbol */
5637 {
5638 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
5639
5640 /* Allocate a table to hold the local symbols if first time */
5641 if (!ptr)
5642 {
5643 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
5644 register unsigned int i;
5645
5646 ptr = (elf_linker_section_pointers_t **)
5647 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
5648
5649 if (!ptr)
5650 return false;
5651
5652 elf_local_ptr_offsets (abfd) = ptr;
5653 for (i = 0; i < num_symbols; i++)
5654 ptr[i] = (elf_linker_section_pointers_t *)0;
5655 }
5656
5657 /* Has this symbol already been allocated, if so, our work is done */
5658 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
5659 rel->r_addend,
5660 lsect->which))
5661 return true;
5662
5663 ptr_linker_section_ptr = &ptr[r_symndx];
5664
5665 if (info->shared)
5666 {
5667 /* If we are generating a shared object, we need to
5668 output a R_<xxx>_RELATIVE reloc so that the
5669 dynamic linker can adjust this GOT entry. */
5670 BFD_ASSERT (lsect->rel_section != NULL);
5671 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
5672 }
5673 }
5674
5675 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
5676 from internal memory. */
5677 BFD_ASSERT (ptr_linker_section_ptr != NULL);
5678 linker_section_ptr = (elf_linker_section_pointers_t *)
5679 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
5680
5681 if (!linker_section_ptr)
5682 return false;
5683
5684 linker_section_ptr->next = *ptr_linker_section_ptr;
5685 linker_section_ptr->addend = rel->r_addend;
5686 linker_section_ptr->which = lsect->which;
5687 linker_section_ptr->written_address_p = false;
5688 *ptr_linker_section_ptr = linker_section_ptr;
5689
5690 #if 0
5691 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
5692 {
5693 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
5694 lsect->hole_offset += ARCH_SIZE / 8;
5695 lsect->sym_offset += ARCH_SIZE / 8;
5696 if (lsect->sym_hash) /* Bump up symbol value if needed */
5697 {
5698 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
5699 #ifdef DEBUG
5700 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
5701 lsect->sym_hash->root.root.string,
5702 (long)ARCH_SIZE / 8,
5703 (long)lsect->sym_hash->root.u.def.value);
5704 #endif
5705 }
5706 }
5707 else
5708 #endif
5709 linker_section_ptr->offset = lsect->section->_raw_size;
5710
5711 lsect->section->_raw_size += ARCH_SIZE / 8;
5712
5713 #ifdef DEBUG
5714 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
5715 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
5716 #endif
5717
5718 return true;
5719 }
5720
5721 \f
5722 #if ARCH_SIZE==64
5723 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
5724 #endif
5725 #if ARCH_SIZE==32
5726 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
5727 #endif
5728
5729 /* Fill in the address for a pointer generated in alinker section. */
5730
5731 bfd_vma
5732 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
5733 bfd *output_bfd;
5734 bfd *input_bfd;
5735 struct bfd_link_info *info;
5736 elf_linker_section_t *lsect;
5737 struct elf_link_hash_entry *h;
5738 bfd_vma relocation;
5739 const Elf_Internal_Rela *rel;
5740 int relative_reloc;
5741 {
5742 elf_linker_section_pointers_t *linker_section_ptr;
5743
5744 BFD_ASSERT (lsect != NULL);
5745
5746 if (h != NULL) /* global symbol */
5747 {
5748 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
5749 rel->r_addend,
5750 lsect->which);
5751
5752 BFD_ASSERT (linker_section_ptr != NULL);
5753
5754 if (! elf_hash_table (info)->dynamic_sections_created
5755 || (info->shared
5756 && info->symbolic
5757 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
5758 {
5759 /* This is actually a static link, or it is a
5760 -Bsymbolic link and the symbol is defined
5761 locally. We must initialize this entry in the
5762 global section.
5763
5764 When doing a dynamic link, we create a .rela.<xxx>
5765 relocation entry to initialize the value. This
5766 is done in the finish_dynamic_symbol routine. */
5767 if (!linker_section_ptr->written_address_p)
5768 {
5769 linker_section_ptr->written_address_p = true;
5770 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5771 lsect->section->contents + linker_section_ptr->offset);
5772 }
5773 }
5774 }
5775 else /* local symbol */
5776 {
5777 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
5778 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
5779 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
5780 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
5781 rel->r_addend,
5782 lsect->which);
5783
5784 BFD_ASSERT (linker_section_ptr != NULL);
5785
5786 /* Write out pointer if it hasn't been rewritten out before */
5787 if (!linker_section_ptr->written_address_p)
5788 {
5789 linker_section_ptr->written_address_p = true;
5790 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
5791 lsect->section->contents + linker_section_ptr->offset);
5792
5793 if (info->shared)
5794 {
5795 asection *srel = lsect->rel_section;
5796 Elf_Internal_Rela outrel;
5797
5798 /* We need to generate a relative reloc for the dynamic linker. */
5799 if (!srel)
5800 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
5801 lsect->rel_name);
5802
5803 BFD_ASSERT (srel != NULL);
5804
5805 outrel.r_offset = (lsect->section->output_section->vma
5806 + lsect->section->output_offset
5807 + linker_section_ptr->offset);
5808 outrel.r_info = ELF_R_INFO (0, relative_reloc);
5809 outrel.r_addend = 0;
5810 elf_swap_reloca_out (output_bfd, &outrel,
5811 (((Elf_External_Rela *)
5812 lsect->section->contents)
5813 + elf_section_data (lsect->section)->rel_count));
5814 ++elf_section_data (lsect->section)->rel_count;
5815 }
5816 }
5817 }
5818
5819 relocation = (lsect->section->output_offset
5820 + linker_section_ptr->offset
5821 - lsect->hole_offset
5822 - lsect->sym_offset);
5823
5824 #ifdef DEBUG
5825 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
5826 lsect->name, (long)relocation, (long)relocation);
5827 #endif
5828
5829 /* Subtract out the addend, because it will get added back in by the normal
5830 processing. */
5831 return relocation - linker_section_ptr->addend;
5832 }
5833 \f
5834 /* Garbage collect unused sections. */
5835
5836 static boolean elf_gc_mark
5837 PARAMS ((struct bfd_link_info *info, asection *sec,
5838 asection * (*gc_mark_hook)
5839 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
5840 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
5841
5842 static boolean elf_gc_sweep
5843 PARAMS ((struct bfd_link_info *info,
5844 boolean (*gc_sweep_hook)
5845 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
5846 const Elf_Internal_Rela *relocs))));
5847
5848 static boolean elf_gc_sweep_symbol
5849 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
5850
5851 static boolean elf_gc_allocate_got_offsets
5852 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
5853
5854 static boolean elf_gc_propagate_vtable_entries_used
5855 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
5856
5857 static boolean elf_gc_smash_unused_vtentry_relocs
5858 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
5859
5860 /* The mark phase of garbage collection. For a given section, mark
5861 it, and all the sections which define symbols to which it refers. */
5862
5863 static boolean
5864 elf_gc_mark (info, sec, gc_mark_hook)
5865 struct bfd_link_info *info;
5866 asection *sec;
5867 asection * (*gc_mark_hook)
5868 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
5869 struct elf_link_hash_entry *, Elf_Internal_Sym *));
5870 {
5871 boolean ret = true;
5872
5873 sec->gc_mark = 1;
5874
5875 /* Look through the section relocs. */
5876
5877 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
5878 {
5879 Elf_Internal_Rela *relstart, *rel, *relend;
5880 Elf_Internal_Shdr *symtab_hdr;
5881 struct elf_link_hash_entry **sym_hashes;
5882 size_t nlocsyms;
5883 size_t extsymoff;
5884 Elf_External_Sym *locsyms, *freesyms = NULL;
5885 bfd *input_bfd = sec->owner;
5886 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
5887
5888 /* GCFIXME: how to arrange so that relocs and symbols are not
5889 reread continually? */
5890
5891 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5892 sym_hashes = elf_sym_hashes (input_bfd);
5893
5894 /* Read the local symbols. */
5895 if (elf_bad_symtab (input_bfd))
5896 {
5897 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5898 extsymoff = 0;
5899 }
5900 else
5901 extsymoff = nlocsyms = symtab_hdr->sh_info;
5902 if (symtab_hdr->contents)
5903 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
5904 else if (nlocsyms == 0)
5905 locsyms = NULL;
5906 else
5907 {
5908 locsyms = freesyms =
5909 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
5910 if (freesyms == NULL
5911 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5912 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
5913 nlocsyms, input_bfd)
5914 != nlocsyms * sizeof (Elf_External_Sym)))
5915 {
5916 ret = false;
5917 goto out1;
5918 }
5919 }
5920
5921 /* Read the relocations. */
5922 relstart = (NAME(_bfd_elf,link_read_relocs)
5923 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
5924 info->keep_memory));
5925 if (relstart == NULL)
5926 {
5927 ret = false;
5928 goto out1;
5929 }
5930 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
5931
5932 for (rel = relstart; rel < relend; rel++)
5933 {
5934 unsigned long r_symndx;
5935 asection *rsec;
5936 struct elf_link_hash_entry *h;
5937 Elf_Internal_Sym s;
5938
5939 r_symndx = ELF_R_SYM (rel->r_info);
5940 if (r_symndx == 0)
5941 continue;
5942
5943 if (elf_bad_symtab (sec->owner))
5944 {
5945 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
5946 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
5947 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
5948 else
5949 {
5950 h = sym_hashes[r_symndx - extsymoff];
5951 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
5952 }
5953 }
5954 else if (r_symndx >= nlocsyms)
5955 {
5956 h = sym_hashes[r_symndx - extsymoff];
5957 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
5958 }
5959 else
5960 {
5961 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
5962 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
5963 }
5964
5965 if (rsec && !rsec->gc_mark)
5966 if (!elf_gc_mark (info, rsec, gc_mark_hook))
5967 {
5968 ret = false;
5969 goto out2;
5970 }
5971 }
5972
5973 out2:
5974 if (!info->keep_memory)
5975 free (relstart);
5976 out1:
5977 if (freesyms)
5978 free (freesyms);
5979 }
5980
5981 return ret;
5982 }
5983
5984 /* The sweep phase of garbage collection. Remove all garbage sections. */
5985
5986 static boolean
5987 elf_gc_sweep (info, gc_sweep_hook)
5988 struct bfd_link_info *info;
5989 boolean (*gc_sweep_hook)
5990 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
5991 const Elf_Internal_Rela *relocs));
5992 {
5993 bfd *sub;
5994
5995 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
5996 {
5997 asection *o;
5998
5999 for (o = sub->sections; o != NULL; o = o->next)
6000 {
6001 /* Keep special sections. Keep .debug sections. */
6002 if ((o->flags & SEC_LINKER_CREATED)
6003 || (o->flags & SEC_DEBUGGING))
6004 o->gc_mark = 1;
6005
6006 if (o->gc_mark)
6007 continue;
6008
6009 /* Skip sweeping sections already excluded. */
6010 if (o->flags & SEC_EXCLUDE)
6011 continue;
6012
6013 /* Since this is early in the link process, it is simple
6014 to remove a section from the output. */
6015 o->flags |= SEC_EXCLUDE;
6016
6017 /* But we also have to update some of the relocation
6018 info we collected before. */
6019 if (gc_sweep_hook
6020 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6021 {
6022 Elf_Internal_Rela *internal_relocs;
6023 boolean r;
6024
6025 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6026 (o->owner, o, NULL, NULL, info->keep_memory));
6027 if (internal_relocs == NULL)
6028 return false;
6029
6030 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6031
6032 if (!info->keep_memory)
6033 free (internal_relocs);
6034
6035 if (!r)
6036 return false;
6037 }
6038 }
6039 }
6040
6041 /* Remove the symbols that were in the swept sections from the dynamic
6042 symbol table. GCFIXME: Anyone know how to get them out of the
6043 static symbol table as well? */
6044 {
6045 int i = 0;
6046
6047 elf_link_hash_traverse (elf_hash_table (info),
6048 elf_gc_sweep_symbol,
6049 (PTR) &i);
6050
6051 elf_hash_table (info)->dynsymcount = i;
6052 }
6053
6054 return true;
6055 }
6056
6057 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6058
6059 static boolean
6060 elf_gc_sweep_symbol (h, idxptr)
6061 struct elf_link_hash_entry *h;
6062 PTR idxptr;
6063 {
6064 int *idx = (int *) idxptr;
6065
6066 if (h->dynindx != -1
6067 && ((h->root.type != bfd_link_hash_defined
6068 && h->root.type != bfd_link_hash_defweak)
6069 || h->root.u.def.section->gc_mark))
6070 h->dynindx = (*idx)++;
6071
6072 return true;
6073 }
6074
6075 /* Propogate collected vtable information. This is called through
6076 elf_link_hash_traverse. */
6077
6078 static boolean
6079 elf_gc_propagate_vtable_entries_used (h, okp)
6080 struct elf_link_hash_entry *h;
6081 PTR okp;
6082 {
6083 /* Those that are not vtables. */
6084 if (h->vtable_parent == NULL)
6085 return true;
6086
6087 /* Those vtables that do not have parents, we cannot merge. */
6088 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6089 return true;
6090
6091 /* If we've already been done, exit. */
6092 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6093 return true;
6094
6095 /* Make sure the parent's table is up to date. */
6096 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6097
6098 if (h->vtable_entries_used == NULL)
6099 {
6100 /* None of this table's entries were referenced. Re-use the
6101 parent's table. */
6102 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6103 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6104 }
6105 else
6106 {
6107 size_t n;
6108 boolean *cu, *pu;
6109
6110 /* Or the parent's entries into ours. */
6111 cu = h->vtable_entries_used;
6112 cu[-1] = true;
6113 pu = h->vtable_parent->vtable_entries_used;
6114 if (pu != NULL)
6115 {
6116 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6117 while (--n != 0)
6118 {
6119 if (*pu) *cu = true;
6120 pu++, cu++;
6121 }
6122 }
6123 }
6124
6125 return true;
6126 }
6127
6128 static boolean
6129 elf_gc_smash_unused_vtentry_relocs (h, okp)
6130 struct elf_link_hash_entry *h;
6131 PTR okp;
6132 {
6133 asection *sec;
6134 bfd_vma hstart, hend;
6135 Elf_Internal_Rela *relstart, *relend, *rel;
6136 struct elf_backend_data *bed;
6137
6138 /* Take care of both those symbols that do not describe vtables as
6139 well as those that are not loaded. */
6140 if (h->vtable_parent == NULL)
6141 return true;
6142
6143 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6144 || h->root.type == bfd_link_hash_defweak);
6145
6146 sec = h->root.u.def.section;
6147 hstart = h->root.u.def.value;
6148 hend = hstart + h->size;
6149
6150 relstart = (NAME(_bfd_elf,link_read_relocs)
6151 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6152 if (!relstart)
6153 return *(boolean *)okp = false;
6154 bed = get_elf_backend_data (sec->owner);
6155 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6156
6157 for (rel = relstart; rel < relend; ++rel)
6158 if (rel->r_offset >= hstart && rel->r_offset < hend)
6159 {
6160 /* If the entry is in use, do nothing. */
6161 if (h->vtable_entries_used
6162 && (rel->r_offset - hstart) < h->vtable_entries_size)
6163 {
6164 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6165 if (h->vtable_entries_used[entry])
6166 continue;
6167 }
6168 /* Otherwise, kill it. */
6169 rel->r_offset = rel->r_info = rel->r_addend = 0;
6170 }
6171
6172 return true;
6173 }
6174
6175 /* Do mark and sweep of unused sections. */
6176
6177 boolean
6178 elf_gc_sections (abfd, info)
6179 bfd *abfd;
6180 struct bfd_link_info *info;
6181 {
6182 boolean ok = true;
6183 bfd *sub;
6184 asection * (*gc_mark_hook)
6185 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6186 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6187
6188 if (!get_elf_backend_data (abfd)->can_gc_sections
6189 || info->relocateable
6190 || elf_hash_table (info)->dynamic_sections_created)
6191 return true;
6192
6193 /* Apply transitive closure to the vtable entry usage info. */
6194 elf_link_hash_traverse (elf_hash_table (info),
6195 elf_gc_propagate_vtable_entries_used,
6196 (PTR) &ok);
6197 if (!ok)
6198 return false;
6199
6200 /* Kill the vtable relocations that were not used. */
6201 elf_link_hash_traverse (elf_hash_table (info),
6202 elf_gc_smash_unused_vtentry_relocs,
6203 (PTR) &ok);
6204 if (!ok)
6205 return false;
6206
6207 /* Grovel through relocs to find out who stays ... */
6208
6209 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6210 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6211 {
6212 asection *o;
6213 for (o = sub->sections; o != NULL; o = o->next)
6214 {
6215 if (o->flags & SEC_KEEP)
6216 if (!elf_gc_mark (info, o, gc_mark_hook))
6217 return false;
6218 }
6219 }
6220
6221 /* ... and mark SEC_EXCLUDE for those that go. */
6222 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6223 return false;
6224
6225 return true;
6226 }
6227 \f
6228 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6229
6230 boolean
6231 elf_gc_record_vtinherit (abfd, sec, h, offset)
6232 bfd *abfd;
6233 asection *sec;
6234 struct elf_link_hash_entry *h;
6235 bfd_vma offset;
6236 {
6237 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6238 struct elf_link_hash_entry **search, *child;
6239 bfd_size_type extsymcount;
6240
6241 /* The sh_info field of the symtab header tells us where the
6242 external symbols start. We don't care about the local symbols at
6243 this point. */
6244 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6245 if (!elf_bad_symtab (abfd))
6246 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6247
6248 sym_hashes = elf_sym_hashes (abfd);
6249 sym_hashes_end = sym_hashes + extsymcount;
6250
6251 /* Hunt down the child symbol, which is in this section at the same
6252 offset as the relocation. */
6253 for (search = sym_hashes; search != sym_hashes_end; ++search)
6254 {
6255 if ((child = *search) != NULL
6256 && (child->root.type == bfd_link_hash_defined
6257 || child->root.type == bfd_link_hash_defweak)
6258 && child->root.u.def.section == sec
6259 && child->root.u.def.value == offset)
6260 goto win;
6261 }
6262
6263 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6264 bfd_get_filename (abfd), sec->name,
6265 (unsigned long)offset);
6266 bfd_set_error (bfd_error_invalid_operation);
6267 return false;
6268
6269 win:
6270 if (!h)
6271 {
6272 /* This *should* only be the absolute section. It could potentially
6273 be that someone has defined a non-global vtable though, which
6274 would be bad. It isn't worth paging in the local symbols to be
6275 sure though; that case should simply be handled by the assembler. */
6276
6277 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6278 }
6279 else
6280 child->vtable_parent = h;
6281
6282 return true;
6283 }
6284
6285 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6286
6287 boolean
6288 elf_gc_record_vtentry (abfd, sec, h, addend)
6289 bfd *abfd ATTRIBUTE_UNUSED;
6290 asection *sec ATTRIBUTE_UNUSED;
6291 struct elf_link_hash_entry *h;
6292 bfd_vma addend;
6293 {
6294 if (addend >= h->vtable_entries_size)
6295 {
6296 size_t size, bytes;
6297 boolean *ptr = h->vtable_entries_used;
6298
6299 /* While the symbol is undefined, we have to be prepared to handle
6300 a zero size. */
6301 if (h->root.type == bfd_link_hash_undefined)
6302 size = addend;
6303 else
6304 {
6305 size = h->size;
6306 if (size < addend)
6307 {
6308 /* Oops! We've got a reference past the defined end of
6309 the table. This is probably a bug -- shall we warn? */
6310 size = addend;
6311 }
6312 }
6313
6314 /* Allocate one extra entry for use as a "done" flag for the
6315 consolidation pass. */
6316 bytes = (size / FILE_ALIGN + 1) * sizeof(boolean);
6317
6318 if (ptr)
6319 {
6320 size_t oldbytes;
6321
6322 ptr = realloc (ptr-1, bytes);
6323 if (ptr == NULL)
6324 return false;
6325
6326 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof(boolean);
6327 memset (ptr + oldbytes, 0, bytes - oldbytes);
6328 }
6329 else
6330 {
6331 ptr = calloc (1, bytes);
6332 if (ptr == NULL)
6333 return false;
6334 }
6335
6336 /* And arrange for that done flag to be at index -1. */
6337 h->vtable_entries_used = ptr+1;
6338 h->vtable_entries_size = size;
6339 }
6340 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6341
6342 return true;
6343 }
6344
6345 /* And an accompanying bit to work out final got entry offsets once
6346 we're done. Should be called from final_link. */
6347
6348 boolean
6349 elf_gc_common_finalize_got_offsets (abfd, info)
6350 bfd *abfd;
6351 struct bfd_link_info *info;
6352 {
6353 bfd *i;
6354 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6355 bfd_vma gotoff;
6356
6357 /* The GOT offset is relative to the .got section, but the GOT header is
6358 put into the .got.plt section, if the backend uses it. */
6359 if (bed->want_got_plt)
6360 gotoff = 0;
6361 else
6362 gotoff = bed->got_header_size;
6363
6364 /* Do the local .got entries first. */
6365 for (i = info->input_bfds; i; i = i->link_next)
6366 {
6367 bfd_signed_vma *local_got = elf_local_got_refcounts (i);
6368 bfd_size_type j, locsymcount;
6369 Elf_Internal_Shdr *symtab_hdr;
6370
6371 if (!local_got)
6372 continue;
6373
6374 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6375 if (elf_bad_symtab (i))
6376 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6377 else
6378 locsymcount = symtab_hdr->sh_info;
6379
6380 for (j = 0; j < locsymcount; ++j)
6381 {
6382 if (local_got[j] > 0)
6383 {
6384 local_got[j] = gotoff;
6385 gotoff += ARCH_SIZE / 8;
6386 }
6387 else
6388 local_got[j] = (bfd_vma) -1;
6389 }
6390 }
6391
6392 /* Then the global .got and .plt entries. */
6393 elf_link_hash_traverse (elf_hash_table (info),
6394 elf_gc_allocate_got_offsets,
6395 (PTR) &gotoff);
6396 return true;
6397 }
6398
6399 /* We need a special top-level link routine to convert got reference counts
6400 to real got offsets. */
6401
6402 static boolean
6403 elf_gc_allocate_got_offsets (h, offarg)
6404 struct elf_link_hash_entry *h;
6405 PTR offarg;
6406 {
6407 bfd_vma *off = (bfd_vma *) offarg;
6408
6409 if (h->got.refcount > 0)
6410 {
6411 h->got.offset = off[0];
6412 off[0] += ARCH_SIZE / 8;
6413 }
6414 else
6415 h->got.offset = (bfd_vma) -1;
6416
6417 return true;
6418 }
6419
6420 /* Many folk need no more in the way of final link than this, once
6421 got entry reference counting is enabled. */
6422
6423 boolean
6424 elf_gc_common_final_link (abfd, info)
6425 bfd *abfd;
6426 struct bfd_link_info *info;
6427 {
6428 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6429 return false;
6430
6431 /* Invoke the regular ELF backend linker to do all the work. */
6432 return elf_bfd_final_link (abfd, info);
6433 }
6434
6435 /* This function will be called though elf_link_hash_traverse to store
6436 all hash value of the exported symbols in an array. */
6437
6438 static boolean
6439 elf_collect_hash_codes (h, data)
6440 struct elf_link_hash_entry *h;
6441 PTR data;
6442 {
6443 unsigned long **valuep = (unsigned long **) data;
6444 const char *name;
6445 char *p;
6446 unsigned long ha;
6447 char *alc = NULL;
6448
6449 /* Ignore indirect symbols. These are added by the versioning code. */
6450 if (h->dynindx == -1)
6451 return true;
6452
6453 name = h->root.root.string;
6454 p = strchr (name, ELF_VER_CHR);
6455 if (p != NULL)
6456 {
6457 alc = bfd_malloc (p - name + 1);
6458 memcpy (alc, name, p - name);
6459 alc[p - name] = '\0';
6460 name = alc;
6461 }
6462
6463 /* Compute the hash value. */
6464 ha = bfd_elf_hash (name);
6465
6466 /* Store the found hash value in the array given as the argument. */
6467 *(*valuep)++ = ha;
6468
6469 /* And store it in the struct so that we can put it in the hash table
6470 later. */
6471 h->elf_hash_value = ha;
6472
6473 if (alc != NULL)
6474 free (alc);
6475
6476 return true;
6477 }
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