2001-05-17 H.J. Lu <hjl@gnu.org>
[deliverable/binutils-gdb.git] / bfd / elflink.h
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001
3 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 /* ELF linker code. */
22
23 /* This struct is used to pass information to routines called via
24 elf_link_hash_traverse which must return failure. */
25
26 struct elf_info_failed
27 {
28 boolean failed;
29 struct bfd_link_info *info;
30 };
31
32 static boolean elf_link_add_object_symbols
33 PARAMS ((bfd *, struct bfd_link_info *));
34 static boolean elf_link_add_archive_symbols
35 PARAMS ((bfd *, struct bfd_link_info *));
36 static boolean elf_merge_symbol
37 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
38 asection **, bfd_vma *, struct elf_link_hash_entry **,
39 boolean *, boolean *, boolean *, boolean));
40 static boolean elf_export_symbol
41 PARAMS ((struct elf_link_hash_entry *, PTR));
42 static boolean elf_fix_symbol_flags
43 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
44 static boolean elf_adjust_dynamic_symbol
45 PARAMS ((struct elf_link_hash_entry *, PTR));
46 static boolean elf_link_find_version_dependencies
47 PARAMS ((struct elf_link_hash_entry *, PTR));
48 static boolean elf_link_find_version_dependencies
49 PARAMS ((struct elf_link_hash_entry *, PTR));
50 static boolean elf_link_assign_sym_version
51 PARAMS ((struct elf_link_hash_entry *, PTR));
52 static boolean elf_collect_hash_codes
53 PARAMS ((struct elf_link_hash_entry *, PTR));
54 static boolean elf_link_read_relocs_from_section
55 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
56 static void elf_link_output_relocs
57 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
58 static boolean elf_link_size_reloc_section
59 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
60 static void elf_link_adjust_relocs
61 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
62 struct elf_link_hash_entry **));
63
64 /* Given an ELF BFD, add symbols to the global hash table as
65 appropriate. */
66
67 boolean
68 elf_bfd_link_add_symbols (abfd, info)
69 bfd *abfd;
70 struct bfd_link_info *info;
71 {
72 switch (bfd_get_format (abfd))
73 {
74 case bfd_object:
75 return elf_link_add_object_symbols (abfd, info);
76 case bfd_archive:
77 return elf_link_add_archive_symbols (abfd, info);
78 default:
79 bfd_set_error (bfd_error_wrong_format);
80 return false;
81 }
82 }
83 \f
84 /* Return true iff this is a non-common, definition of a non-function symbol. */
85 static boolean
86 is_global_data_symbol_definition (abfd, sym)
87 bfd * abfd ATTRIBUTE_UNUSED;
88 Elf_Internal_Sym * sym;
89 {
90 /* Local symbols do not count, but target specific ones might. */
91 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
92 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
93 return false;
94
95 /* Function symbols do not count. */
96 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
97 return false;
98
99 /* If the section is undefined, then so is the symbol. */
100 if (sym->st_shndx == SHN_UNDEF)
101 return false;
102
103 /* If the symbol is defined in the common section, then
104 it is a common definition and so does not count. */
105 if (sym->st_shndx == SHN_COMMON)
106 return false;
107
108 /* If the symbol is in a target specific section then we
109 must rely upon the backend to tell us what it is. */
110 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
111 /* FIXME - this function is not coded yet:
112
113 return _bfd_is_global_symbol_definition (abfd, sym);
114
115 Instead for now assume that the definition is not global,
116 Even if this is wrong, at least the linker will behave
117 in the same way that it used to do. */
118 return false;
119
120 return true;
121 }
122
123 /* Search the symbol table of the archive element of the archive ABFD
124 whoes archive map contains a mention of SYMDEF, and determine if
125 the symbol is defined in this element. */
126 static boolean
127 elf_link_is_defined_archive_symbol (abfd, symdef)
128 bfd * abfd;
129 carsym * symdef;
130 {
131 Elf_Internal_Shdr * hdr;
132 Elf_External_Sym * esym;
133 Elf_External_Sym * esymend;
134 Elf_External_Sym * buf = NULL;
135 size_t symcount;
136 size_t extsymcount;
137 size_t extsymoff;
138 boolean result = false;
139
140 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
141 if (abfd == (bfd *) NULL)
142 return false;
143
144 if (! bfd_check_format (abfd, bfd_object))
145 return false;
146
147 /* If we have already included the element containing this symbol in the
148 link then we do not need to include it again. Just claim that any symbol
149 it contains is not a definition, so that our caller will not decide to
150 (re)include this element. */
151 if (abfd->archive_pass)
152 return false;
153
154 /* Select the appropriate symbol table. */
155 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
156 hdr = &elf_tdata (abfd)->symtab_hdr;
157 else
158 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
159
160 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
161
162 /* The sh_info field of the symtab header tells us where the
163 external symbols start. We don't care about the local symbols. */
164 if (elf_bad_symtab (abfd))
165 {
166 extsymcount = symcount;
167 extsymoff = 0;
168 }
169 else
170 {
171 extsymcount = symcount - hdr->sh_info;
172 extsymoff = hdr->sh_info;
173 }
174
175 buf = ((Elf_External_Sym *)
176 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
177 if (buf == NULL && extsymcount != 0)
178 return false;
179
180 /* Read in the symbol table.
181 FIXME: This ought to be cached somewhere. */
182 if (bfd_seek (abfd,
183 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
184 SEEK_SET) != 0
185 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
186 != extsymcount * sizeof (Elf_External_Sym)))
187 {
188 free (buf);
189 return false;
190 }
191
192 /* Scan the symbol table looking for SYMDEF. */
193 esymend = buf + extsymcount;
194 for (esym = buf;
195 esym < esymend;
196 esym++)
197 {
198 Elf_Internal_Sym sym;
199 const char * name;
200
201 elf_swap_symbol_in (abfd, esym, & sym);
202
203 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
204 if (name == (const char *) NULL)
205 break;
206
207 if (strcmp (name, symdef->name) == 0)
208 {
209 result = is_global_data_symbol_definition (abfd, & sym);
210 break;
211 }
212 }
213
214 free (buf);
215
216 return result;
217 }
218 \f
219 /* Add symbols from an ELF archive file to the linker hash table. We
220 don't use _bfd_generic_link_add_archive_symbols because of a
221 problem which arises on UnixWare. The UnixWare libc.so is an
222 archive which includes an entry libc.so.1 which defines a bunch of
223 symbols. The libc.so archive also includes a number of other
224 object files, which also define symbols, some of which are the same
225 as those defined in libc.so.1. Correct linking requires that we
226 consider each object file in turn, and include it if it defines any
227 symbols we need. _bfd_generic_link_add_archive_symbols does not do
228 this; it looks through the list of undefined symbols, and includes
229 any object file which defines them. When this algorithm is used on
230 UnixWare, it winds up pulling in libc.so.1 early and defining a
231 bunch of symbols. This means that some of the other objects in the
232 archive are not included in the link, which is incorrect since they
233 precede libc.so.1 in the archive.
234
235 Fortunately, ELF archive handling is simpler than that done by
236 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
237 oddities. In ELF, if we find a symbol in the archive map, and the
238 symbol is currently undefined, we know that we must pull in that
239 object file.
240
241 Unfortunately, we do have to make multiple passes over the symbol
242 table until nothing further is resolved. */
243
244 static boolean
245 elf_link_add_archive_symbols (abfd, info)
246 bfd *abfd;
247 struct bfd_link_info *info;
248 {
249 symindex c;
250 boolean *defined = NULL;
251 boolean *included = NULL;
252 carsym *symdefs;
253 boolean loop;
254
255 if (! bfd_has_map (abfd))
256 {
257 /* An empty archive is a special case. */
258 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
259 return true;
260 bfd_set_error (bfd_error_no_armap);
261 return false;
262 }
263
264 /* Keep track of all symbols we know to be already defined, and all
265 files we know to be already included. This is to speed up the
266 second and subsequent passes. */
267 c = bfd_ardata (abfd)->symdef_count;
268 if (c == 0)
269 return true;
270 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
271 included = (boolean *) bfd_malloc (c * sizeof (boolean));
272 if (defined == (boolean *) NULL || included == (boolean *) NULL)
273 goto error_return;
274 memset (defined, 0, c * sizeof (boolean));
275 memset (included, 0, c * sizeof (boolean));
276
277 symdefs = bfd_ardata (abfd)->symdefs;
278
279 do
280 {
281 file_ptr last;
282 symindex i;
283 carsym *symdef;
284 carsym *symdefend;
285
286 loop = false;
287 last = -1;
288
289 symdef = symdefs;
290 symdefend = symdef + c;
291 for (i = 0; symdef < symdefend; symdef++, i++)
292 {
293 struct elf_link_hash_entry *h;
294 bfd *element;
295 struct bfd_link_hash_entry *undefs_tail;
296 symindex mark;
297
298 if (defined[i] || included[i])
299 continue;
300 if (symdef->file_offset == last)
301 {
302 included[i] = true;
303 continue;
304 }
305
306 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
307 false, false, false);
308
309 if (h == NULL)
310 {
311 char *p, *copy;
312
313 /* If this is a default version (the name contains @@),
314 look up the symbol again without the version. The
315 effect is that references to the symbol without the
316 version will be matched by the default symbol in the
317 archive. */
318
319 p = strchr (symdef->name, ELF_VER_CHR);
320 if (p == NULL || p[1] != ELF_VER_CHR)
321 continue;
322
323 copy = bfd_alloc (abfd, p - symdef->name + 1);
324 if (copy == NULL)
325 goto error_return;
326 memcpy (copy, symdef->name, p - symdef->name);
327 copy[p - symdef->name] = '\0';
328
329 h = elf_link_hash_lookup (elf_hash_table (info), copy,
330 false, false, false);
331
332 bfd_release (abfd, copy);
333 }
334
335 if (h == NULL)
336 continue;
337
338 if (h->root.type == bfd_link_hash_common)
339 {
340 /* We currently have a common symbol. The archive map contains
341 a reference to this symbol, so we may want to include it. We
342 only want to include it however, if this archive element
343 contains a definition of the symbol, not just another common
344 declaration of it.
345
346 Unfortunately some archivers (including GNU ar) will put
347 declarations of common symbols into their archive maps, as
348 well as real definitions, so we cannot just go by the archive
349 map alone. Instead we must read in the element's symbol
350 table and check that to see what kind of symbol definition
351 this is. */
352 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
353 continue;
354 }
355 else if (h->root.type != bfd_link_hash_undefined)
356 {
357 if (h->root.type != bfd_link_hash_undefweak)
358 defined[i] = true;
359 continue;
360 }
361
362 /* We need to include this archive member. */
363 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
364 if (element == (bfd *) NULL)
365 goto error_return;
366
367 if (! bfd_check_format (element, bfd_object))
368 goto error_return;
369
370 /* Doublecheck that we have not included this object
371 already--it should be impossible, but there may be
372 something wrong with the archive. */
373 if (element->archive_pass != 0)
374 {
375 bfd_set_error (bfd_error_bad_value);
376 goto error_return;
377 }
378 element->archive_pass = 1;
379
380 undefs_tail = info->hash->undefs_tail;
381
382 if (! (*info->callbacks->add_archive_element) (info, element,
383 symdef->name))
384 goto error_return;
385 if (! elf_link_add_object_symbols (element, info))
386 goto error_return;
387
388 /* If there are any new undefined symbols, we need to make
389 another pass through the archive in order to see whether
390 they can be defined. FIXME: This isn't perfect, because
391 common symbols wind up on undefs_tail and because an
392 undefined symbol which is defined later on in this pass
393 does not require another pass. This isn't a bug, but it
394 does make the code less efficient than it could be. */
395 if (undefs_tail != info->hash->undefs_tail)
396 loop = true;
397
398 /* Look backward to mark all symbols from this object file
399 which we have already seen in this pass. */
400 mark = i;
401 do
402 {
403 included[mark] = true;
404 if (mark == 0)
405 break;
406 --mark;
407 }
408 while (symdefs[mark].file_offset == symdef->file_offset);
409
410 /* We mark subsequent symbols from this object file as we go
411 on through the loop. */
412 last = symdef->file_offset;
413 }
414 }
415 while (loop);
416
417 free (defined);
418 free (included);
419
420 return true;
421
422 error_return:
423 if (defined != (boolean *) NULL)
424 free (defined);
425 if (included != (boolean *) NULL)
426 free (included);
427 return false;
428 }
429
430 /* This function is called when we want to define a new symbol. It
431 handles the various cases which arise when we find a definition in
432 a dynamic object, or when there is already a definition in a
433 dynamic object. The new symbol is described by NAME, SYM, PSEC,
434 and PVALUE. We set SYM_HASH to the hash table entry. We set
435 OVERRIDE if the old symbol is overriding a new definition. We set
436 TYPE_CHANGE_OK if it is OK for the type to change. We set
437 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
438 change, we mean that we shouldn't warn if the type or size does
439 change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
440 a shared object. */
441
442 static boolean
443 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
444 override, type_change_ok, size_change_ok, dt_needed)
445 bfd *abfd;
446 struct bfd_link_info *info;
447 const char *name;
448 Elf_Internal_Sym *sym;
449 asection **psec;
450 bfd_vma *pvalue;
451 struct elf_link_hash_entry **sym_hash;
452 boolean *override;
453 boolean *type_change_ok;
454 boolean *size_change_ok;
455 boolean dt_needed;
456 {
457 asection *sec;
458 struct elf_link_hash_entry *h;
459 int bind;
460 bfd *oldbfd;
461 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
462
463 *override = false;
464
465 sec = *psec;
466 bind = ELF_ST_BIND (sym->st_info);
467
468 if (! bfd_is_und_section (sec))
469 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
470 else
471 h = ((struct elf_link_hash_entry *)
472 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
473 if (h == NULL)
474 return false;
475 *sym_hash = h;
476
477 /* This code is for coping with dynamic objects, and is only useful
478 if we are doing an ELF link. */
479 if (info->hash->creator != abfd->xvec)
480 return true;
481
482 /* For merging, we only care about real symbols. */
483
484 while (h->root.type == bfd_link_hash_indirect
485 || h->root.type == bfd_link_hash_warning)
486 h = (struct elf_link_hash_entry *) h->root.u.i.link;
487
488 /* If we just created the symbol, mark it as being an ELF symbol.
489 Other than that, there is nothing to do--there is no merge issue
490 with a newly defined symbol--so we just return. */
491
492 if (h->root.type == bfd_link_hash_new)
493 {
494 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
495 return true;
496 }
497
498 /* OLDBFD is a BFD associated with the existing symbol. */
499
500 switch (h->root.type)
501 {
502 default:
503 oldbfd = NULL;
504 break;
505
506 case bfd_link_hash_undefined:
507 case bfd_link_hash_undefweak:
508 oldbfd = h->root.u.undef.abfd;
509 break;
510
511 case bfd_link_hash_defined:
512 case bfd_link_hash_defweak:
513 oldbfd = h->root.u.def.section->owner;
514 break;
515
516 case bfd_link_hash_common:
517 oldbfd = h->root.u.c.p->section->owner;
518 break;
519 }
520
521 /* In cases involving weak versioned symbols, we may wind up trying
522 to merge a symbol with itself. Catch that here, to avoid the
523 confusion that results if we try to override a symbol with
524 itself. The additional tests catch cases like
525 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
526 dynamic object, which we do want to handle here. */
527 if (abfd == oldbfd
528 && ((abfd->flags & DYNAMIC) == 0
529 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
530 return true;
531
532 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
533 respectively, is from a dynamic object. */
534
535 if ((abfd->flags & DYNAMIC) != 0)
536 newdyn = true;
537 else
538 newdyn = false;
539
540 if (oldbfd != NULL)
541 olddyn = (oldbfd->flags & DYNAMIC) != 0;
542 else
543 {
544 asection *hsec;
545
546 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
547 indices used by MIPS ELF. */
548 switch (h->root.type)
549 {
550 default:
551 hsec = NULL;
552 break;
553
554 case bfd_link_hash_defined:
555 case bfd_link_hash_defweak:
556 hsec = h->root.u.def.section;
557 break;
558
559 case bfd_link_hash_common:
560 hsec = h->root.u.c.p->section;
561 break;
562 }
563
564 if (hsec == NULL)
565 olddyn = false;
566 else
567 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
568 }
569
570 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
571 respectively, appear to be a definition rather than reference. */
572
573 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
574 newdef = false;
575 else
576 newdef = true;
577
578 if (h->root.type == bfd_link_hash_undefined
579 || h->root.type == bfd_link_hash_undefweak
580 || h->root.type == bfd_link_hash_common)
581 olddef = false;
582 else
583 olddef = true;
584
585 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
586 symbol, respectively, appears to be a common symbol in a dynamic
587 object. If a symbol appears in an uninitialized section, and is
588 not weak, and is not a function, then it may be a common symbol
589 which was resolved when the dynamic object was created. We want
590 to treat such symbols specially, because they raise special
591 considerations when setting the symbol size: if the symbol
592 appears as a common symbol in a regular object, and the size in
593 the regular object is larger, we must make sure that we use the
594 larger size. This problematic case can always be avoided in C,
595 but it must be handled correctly when using Fortran shared
596 libraries.
597
598 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
599 likewise for OLDDYNCOMMON and OLDDEF.
600
601 Note that this test is just a heuristic, and that it is quite
602 possible to have an uninitialized symbol in a shared object which
603 is really a definition, rather than a common symbol. This could
604 lead to some minor confusion when the symbol really is a common
605 symbol in some regular object. However, I think it will be
606 harmless. */
607
608 if (newdyn
609 && newdef
610 && (sec->flags & SEC_ALLOC) != 0
611 && (sec->flags & SEC_LOAD) == 0
612 && sym->st_size > 0
613 && bind != STB_WEAK
614 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
615 newdyncommon = true;
616 else
617 newdyncommon = false;
618
619 if (olddyn
620 && olddef
621 && h->root.type == bfd_link_hash_defined
622 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
623 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
624 && (h->root.u.def.section->flags & SEC_LOAD) == 0
625 && h->size > 0
626 && h->type != STT_FUNC)
627 olddyncommon = true;
628 else
629 olddyncommon = false;
630
631 /* It's OK to change the type if either the existing symbol or the
632 new symbol is weak unless it comes from a DT_NEEDED entry of
633 a shared object, in which case, the DT_NEEDED entry may not be
634 required at the run time. */
635
636 if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
637 || h->root.type == bfd_link_hash_undefweak
638 || bind == STB_WEAK)
639 *type_change_ok = true;
640
641 /* It's OK to change the size if either the existing symbol or the
642 new symbol is weak, or if the old symbol is undefined. */
643
644 if (*type_change_ok
645 || h->root.type == bfd_link_hash_undefined)
646 *size_change_ok = true;
647
648 /* If both the old and the new symbols look like common symbols in a
649 dynamic object, set the size of the symbol to the larger of the
650 two. */
651
652 if (olddyncommon
653 && newdyncommon
654 && sym->st_size != h->size)
655 {
656 /* Since we think we have two common symbols, issue a multiple
657 common warning if desired. Note that we only warn if the
658 size is different. If the size is the same, we simply let
659 the old symbol override the new one as normally happens with
660 symbols defined in dynamic objects. */
661
662 if (! ((*info->callbacks->multiple_common)
663 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
664 h->size, abfd, bfd_link_hash_common, sym->st_size)))
665 return false;
666
667 if (sym->st_size > h->size)
668 h->size = sym->st_size;
669
670 *size_change_ok = true;
671 }
672
673 /* If we are looking at a dynamic object, and we have found a
674 definition, we need to see if the symbol was already defined by
675 some other object. If so, we want to use the existing
676 definition, and we do not want to report a multiple symbol
677 definition error; we do this by clobbering *PSEC to be
678 bfd_und_section_ptr.
679
680 We treat a common symbol as a definition if the symbol in the
681 shared library is a function, since common symbols always
682 represent variables; this can cause confusion in principle, but
683 any such confusion would seem to indicate an erroneous program or
684 shared library. We also permit a common symbol in a regular
685 object to override a weak symbol in a shared object.
686
687 We prefer a non-weak definition in a shared library to a weak
688 definition in the executable unless it comes from a DT_NEEDED
689 entry of a shared object, in which case, the DT_NEEDED entry
690 may not be required at the run time. */
691
692 if (newdyn
693 && newdef
694 && (olddef
695 || (h->root.type == bfd_link_hash_common
696 && (bind == STB_WEAK
697 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
698 && (h->root.type != bfd_link_hash_defweak
699 || dt_needed
700 || bind == STB_WEAK))
701 {
702 *override = true;
703 newdef = false;
704 newdyncommon = false;
705
706 *psec = sec = bfd_und_section_ptr;
707 *size_change_ok = true;
708
709 /* If we get here when the old symbol is a common symbol, then
710 we are explicitly letting it override a weak symbol or
711 function in a dynamic object, and we don't want to warn about
712 a type change. If the old symbol is a defined symbol, a type
713 change warning may still be appropriate. */
714
715 if (h->root.type == bfd_link_hash_common)
716 *type_change_ok = true;
717 }
718
719 /* Handle the special case of an old common symbol merging with a
720 new symbol which looks like a common symbol in a shared object.
721 We change *PSEC and *PVALUE to make the new symbol look like a
722 common symbol, and let _bfd_generic_link_add_one_symbol will do
723 the right thing. */
724
725 if (newdyncommon
726 && h->root.type == bfd_link_hash_common)
727 {
728 *override = true;
729 newdef = false;
730 newdyncommon = false;
731 *pvalue = sym->st_size;
732 *psec = sec = bfd_com_section_ptr;
733 *size_change_ok = true;
734 }
735
736 /* If the old symbol is from a dynamic object, and the new symbol is
737 a definition which is not from a dynamic object, then the new
738 symbol overrides the old symbol. Symbols from regular files
739 always take precedence over symbols from dynamic objects, even if
740 they are defined after the dynamic object in the link.
741
742 As above, we again permit a common symbol in a regular object to
743 override a definition in a shared object if the shared object
744 symbol is a function or is weak.
745
746 As above, we permit a non-weak definition in a shared object to
747 override a weak definition in a regular object. */
748
749 if (! newdyn
750 && (newdef
751 || (bfd_is_com_section (sec)
752 && (h->root.type == bfd_link_hash_defweak
753 || h->type == STT_FUNC)))
754 && olddyn
755 && olddef
756 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
757 && (bind != STB_WEAK
758 || h->root.type == bfd_link_hash_defweak))
759 {
760 /* Change the hash table entry to undefined, and let
761 _bfd_generic_link_add_one_symbol do the right thing with the
762 new definition. */
763
764 h->root.type = bfd_link_hash_undefined;
765 h->root.u.undef.abfd = h->root.u.def.section->owner;
766 *size_change_ok = true;
767
768 olddef = false;
769 olddyncommon = false;
770
771 /* We again permit a type change when a common symbol may be
772 overriding a function. */
773
774 if (bfd_is_com_section (sec))
775 *type_change_ok = true;
776
777 /* This union may have been set to be non-NULL when this symbol
778 was seen in a dynamic object. We must force the union to be
779 NULL, so that it is correct for a regular symbol. */
780
781 h->verinfo.vertree = NULL;
782
783 /* In this special case, if H is the target of an indirection,
784 we want the caller to frob with H rather than with the
785 indirect symbol. That will permit the caller to redefine the
786 target of the indirection, rather than the indirect symbol
787 itself. FIXME: This will break the -y option if we store a
788 symbol with a different name. */
789 *sym_hash = h;
790 }
791
792 /* Handle the special case of a new common symbol merging with an
793 old symbol that looks like it might be a common symbol defined in
794 a shared object. Note that we have already handled the case in
795 which a new common symbol should simply override the definition
796 in the shared library. */
797
798 if (! newdyn
799 && bfd_is_com_section (sec)
800 && olddyncommon)
801 {
802 /* It would be best if we could set the hash table entry to a
803 common symbol, but we don't know what to use for the section
804 or the alignment. */
805 if (! ((*info->callbacks->multiple_common)
806 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
807 h->size, abfd, bfd_link_hash_common, sym->st_size)))
808 return false;
809
810 /* If the predumed common symbol in the dynamic object is
811 larger, pretend that the new symbol has its size. */
812
813 if (h->size > *pvalue)
814 *pvalue = h->size;
815
816 /* FIXME: We no longer know the alignment required by the symbol
817 in the dynamic object, so we just wind up using the one from
818 the regular object. */
819
820 olddef = false;
821 olddyncommon = false;
822
823 h->root.type = bfd_link_hash_undefined;
824 h->root.u.undef.abfd = h->root.u.def.section->owner;
825
826 *size_change_ok = true;
827 *type_change_ok = true;
828
829 h->verinfo.vertree = NULL;
830 }
831
832 /* Handle the special case of a weak definition in a regular object
833 followed by a non-weak definition in a shared object. In this
834 case, we prefer the definition in the shared object unless it
835 comes from a DT_NEEDED entry of a shared object, in which case,
836 the DT_NEEDED entry may not be required at the run time. */
837 if (olddef
838 && ! dt_needed
839 && h->root.type == bfd_link_hash_defweak
840 && newdef
841 && newdyn
842 && bind != STB_WEAK)
843 {
844 /* To make this work we have to frob the flags so that the rest
845 of the code does not think we are using the regular
846 definition. */
847 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
848 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
849 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
850 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
851 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
852 | ELF_LINK_HASH_DEF_DYNAMIC);
853
854 /* If H is the target of an indirection, we want the caller to
855 use H rather than the indirect symbol. Otherwise if we are
856 defining a new indirect symbol we will wind up attaching it
857 to the entry we are overriding. */
858 *sym_hash = h;
859 }
860
861 /* Handle the special case of a non-weak definition in a shared
862 object followed by a weak definition in a regular object. In
863 this case we prefer to definition in the shared object. To make
864 this work we have to tell the caller to not treat the new symbol
865 as a definition. */
866 if (olddef
867 && olddyn
868 && h->root.type != bfd_link_hash_defweak
869 && newdef
870 && ! newdyn
871 && bind == STB_WEAK)
872 *override = true;
873
874 return true;
875 }
876
877 /* Add symbols from an ELF object file to the linker hash table. */
878
879 static boolean
880 elf_link_add_object_symbols (abfd, info)
881 bfd *abfd;
882 struct bfd_link_info *info;
883 {
884 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
885 const Elf_Internal_Sym *,
886 const char **, flagword *,
887 asection **, bfd_vma *));
888 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
889 asection *, const Elf_Internal_Rela *));
890 boolean collect;
891 Elf_Internal_Shdr *hdr;
892 size_t symcount;
893 size_t extsymcount;
894 size_t extsymoff;
895 Elf_External_Sym *buf = NULL;
896 struct elf_link_hash_entry **sym_hash;
897 boolean dynamic;
898 Elf_External_Versym *extversym = NULL;
899 Elf_External_Versym *ever;
900 Elf_External_Dyn *dynbuf = NULL;
901 struct elf_link_hash_entry *weaks;
902 Elf_External_Sym *esym;
903 Elf_External_Sym *esymend;
904 struct elf_backend_data *bed;
905 boolean dt_needed;
906
907 bed = get_elf_backend_data (abfd);
908 add_symbol_hook = bed->elf_add_symbol_hook;
909 collect = bed->collect;
910
911 if ((abfd->flags & DYNAMIC) == 0)
912 dynamic = false;
913 else
914 {
915 dynamic = true;
916
917 /* You can't use -r against a dynamic object. Also, there's no
918 hope of using a dynamic object which does not exactly match
919 the format of the output file. */
920 if (info->relocateable || info->hash->creator != abfd->xvec)
921 {
922 bfd_set_error (bfd_error_invalid_operation);
923 goto error_return;
924 }
925 }
926
927 /* As a GNU extension, any input sections which are named
928 .gnu.warning.SYMBOL are treated as warning symbols for the given
929 symbol. This differs from .gnu.warning sections, which generate
930 warnings when they are included in an output file. */
931 if (! info->shared)
932 {
933 asection *s;
934
935 for (s = abfd->sections; s != NULL; s = s->next)
936 {
937 const char *name;
938
939 name = bfd_get_section_name (abfd, s);
940 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
941 {
942 char *msg;
943 bfd_size_type sz;
944
945 name += sizeof ".gnu.warning." - 1;
946
947 /* If this is a shared object, then look up the symbol
948 in the hash table. If it is there, and it is already
949 been defined, then we will not be using the entry
950 from this shared object, so we don't need to warn.
951 FIXME: If we see the definition in a regular object
952 later on, we will warn, but we shouldn't. The only
953 fix is to keep track of what warnings we are supposed
954 to emit, and then handle them all at the end of the
955 link. */
956 if (dynamic && abfd->xvec == info->hash->creator)
957 {
958 struct elf_link_hash_entry *h;
959
960 h = elf_link_hash_lookup (elf_hash_table (info), name,
961 false, false, true);
962
963 /* FIXME: What about bfd_link_hash_common? */
964 if (h != NULL
965 && (h->root.type == bfd_link_hash_defined
966 || h->root.type == bfd_link_hash_defweak))
967 {
968 /* We don't want to issue this warning. Clobber
969 the section size so that the warning does not
970 get copied into the output file. */
971 s->_raw_size = 0;
972 continue;
973 }
974 }
975
976 sz = bfd_section_size (abfd, s);
977 msg = (char *) bfd_alloc (abfd, sz + 1);
978 if (msg == NULL)
979 goto error_return;
980
981 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
982 goto error_return;
983
984 msg[sz] = '\0';
985
986 if (! (_bfd_generic_link_add_one_symbol
987 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
988 false, collect, (struct bfd_link_hash_entry **) NULL)))
989 goto error_return;
990
991 if (! info->relocateable)
992 {
993 /* Clobber the section size so that the warning does
994 not get copied into the output file. */
995 s->_raw_size = 0;
996 }
997 }
998 }
999 }
1000
1001 /* If this is a dynamic object, we always link against the .dynsym
1002 symbol table, not the .symtab symbol table. The dynamic linker
1003 will only see the .dynsym symbol table, so there is no reason to
1004 look at .symtab for a dynamic object. */
1005
1006 if (! dynamic || elf_dynsymtab (abfd) == 0)
1007 hdr = &elf_tdata (abfd)->symtab_hdr;
1008 else
1009 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1010
1011 if (dynamic)
1012 {
1013 /* Read in any version definitions. */
1014
1015 if (! _bfd_elf_slurp_version_tables (abfd))
1016 goto error_return;
1017
1018 /* Read in the symbol versions, but don't bother to convert them
1019 to internal format. */
1020 if (elf_dynversym (abfd) != 0)
1021 {
1022 Elf_Internal_Shdr *versymhdr;
1023
1024 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1025 extversym = (Elf_External_Versym *) bfd_malloc (versymhdr->sh_size);
1026 if (extversym == NULL)
1027 goto error_return;
1028 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1029 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1030 != versymhdr->sh_size))
1031 goto error_return;
1032 }
1033 }
1034
1035 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1036
1037 /* The sh_info field of the symtab header tells us where the
1038 external symbols start. We don't care about the local symbols at
1039 this point. */
1040 if (elf_bad_symtab (abfd))
1041 {
1042 extsymcount = symcount;
1043 extsymoff = 0;
1044 }
1045 else
1046 {
1047 extsymcount = symcount - hdr->sh_info;
1048 extsymoff = hdr->sh_info;
1049 }
1050
1051 buf = ((Elf_External_Sym *)
1052 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1053 if (buf == NULL && extsymcount != 0)
1054 goto error_return;
1055
1056 /* We store a pointer to the hash table entry for each external
1057 symbol. */
1058 sym_hash = ((struct elf_link_hash_entry **)
1059 bfd_alloc (abfd,
1060 extsymcount * sizeof (struct elf_link_hash_entry *)));
1061 if (sym_hash == NULL)
1062 goto error_return;
1063 elf_sym_hashes (abfd) = sym_hash;
1064
1065 dt_needed = false;
1066
1067 if (! dynamic)
1068 {
1069 /* If we are creating a shared library, create all the dynamic
1070 sections immediately. We need to attach them to something,
1071 so we attach them to this BFD, provided it is the right
1072 format. FIXME: If there are no input BFD's of the same
1073 format as the output, we can't make a shared library. */
1074 if (info->shared
1075 && ! elf_hash_table (info)->dynamic_sections_created
1076 && abfd->xvec == info->hash->creator)
1077 {
1078 if (! elf_link_create_dynamic_sections (abfd, info))
1079 goto error_return;
1080 }
1081 }
1082 else
1083 {
1084 asection *s;
1085 boolean add_needed;
1086 const char *name;
1087 bfd_size_type oldsize;
1088 bfd_size_type strindex;
1089
1090 /* Find the name to use in a DT_NEEDED entry that refers to this
1091 object. If the object has a DT_SONAME entry, we use it.
1092 Otherwise, if the generic linker stuck something in
1093 elf_dt_name, we use that. Otherwise, we just use the file
1094 name. If the generic linker put a null string into
1095 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1096 there is a DT_SONAME entry. */
1097 add_needed = true;
1098 name = basename (bfd_get_filename (abfd));
1099 if (elf_dt_name (abfd) != NULL)
1100 {
1101 name = elf_dt_name (abfd);
1102 if (*name == '\0')
1103 {
1104 if (elf_dt_soname (abfd) != NULL)
1105 dt_needed = true;
1106
1107 add_needed = false;
1108 }
1109 }
1110 s = bfd_get_section_by_name (abfd, ".dynamic");
1111 if (s != NULL)
1112 {
1113 Elf_External_Dyn *extdyn;
1114 Elf_External_Dyn *extdynend;
1115 int elfsec;
1116 unsigned long link;
1117 int rpath;
1118 int runpath;
1119
1120 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1121 if (dynbuf == NULL)
1122 goto error_return;
1123
1124 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1125 (file_ptr) 0, s->_raw_size))
1126 goto error_return;
1127
1128 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1129 if (elfsec == -1)
1130 goto error_return;
1131 link = elf_elfsections (abfd)[elfsec]->sh_link;
1132
1133 {
1134 /* The shared libraries distributed with hpux11 have a bogus
1135 sh_link field for the ".dynamic" section. This code detects
1136 when LINK refers to a section that is not a string table and
1137 tries to find the string table for the ".dynsym" section
1138 instead. */
1139 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1140 if (hdr->sh_type != SHT_STRTAB)
1141 {
1142 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1143 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1144 if (elfsec == -1)
1145 goto error_return;
1146 link = elf_elfsections (abfd)[elfsec]->sh_link;
1147 }
1148 }
1149
1150 extdyn = dynbuf;
1151 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1152 rpath = 0;
1153 runpath = 0;
1154 for (; extdyn < extdynend; extdyn++)
1155 {
1156 Elf_Internal_Dyn dyn;
1157
1158 elf_swap_dyn_in (abfd, extdyn, &dyn);
1159 if (dyn.d_tag == DT_SONAME)
1160 {
1161 name = bfd_elf_string_from_elf_section (abfd, link,
1162 dyn.d_un.d_val);
1163 if (name == NULL)
1164 goto error_return;
1165 }
1166 if (dyn.d_tag == DT_NEEDED)
1167 {
1168 struct bfd_link_needed_list *n, **pn;
1169 char *fnm, *anm;
1170
1171 n = ((struct bfd_link_needed_list *)
1172 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1173 fnm = bfd_elf_string_from_elf_section (abfd, link,
1174 dyn.d_un.d_val);
1175 if (n == NULL || fnm == NULL)
1176 goto error_return;
1177 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1178 if (anm == NULL)
1179 goto error_return;
1180 strcpy (anm, fnm);
1181 n->name = anm;
1182 n->by = abfd;
1183 n->next = NULL;
1184 for (pn = &elf_hash_table (info)->needed;
1185 *pn != NULL;
1186 pn = &(*pn)->next)
1187 ;
1188 *pn = n;
1189 }
1190 if (dyn.d_tag == DT_RUNPATH)
1191 {
1192 struct bfd_link_needed_list *n, **pn;
1193 char *fnm, *anm;
1194
1195 /* When we see DT_RPATH before DT_RUNPATH, we have
1196 to clear runpath. Do _NOT_ bfd_release, as that
1197 frees all more recently bfd_alloc'd blocks as
1198 well. */
1199 if (rpath && elf_hash_table (info)->runpath)
1200 elf_hash_table (info)->runpath = NULL;
1201
1202 n = ((struct bfd_link_needed_list *)
1203 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1204 fnm = bfd_elf_string_from_elf_section (abfd, link,
1205 dyn.d_un.d_val);
1206 if (n == NULL || fnm == NULL)
1207 goto error_return;
1208 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1209 if (anm == NULL)
1210 goto error_return;
1211 strcpy (anm, fnm);
1212 n->name = anm;
1213 n->by = abfd;
1214 n->next = NULL;
1215 for (pn = &elf_hash_table (info)->runpath;
1216 *pn != NULL;
1217 pn = &(*pn)->next)
1218 ;
1219 *pn = n;
1220 runpath = 1;
1221 rpath = 0;
1222 }
1223 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
1224 if (!runpath && dyn.d_tag == DT_RPATH)
1225 {
1226 struct bfd_link_needed_list *n, **pn;
1227 char *fnm, *anm;
1228
1229 n = ((struct bfd_link_needed_list *)
1230 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1231 fnm = bfd_elf_string_from_elf_section (abfd, link,
1232 dyn.d_un.d_val);
1233 if (n == NULL || fnm == NULL)
1234 goto error_return;
1235 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1236 if (anm == NULL)
1237 goto error_return;
1238 strcpy (anm, fnm);
1239 n->name = anm;
1240 n->by = abfd;
1241 n->next = NULL;
1242 for (pn = &elf_hash_table (info)->runpath;
1243 *pn != NULL;
1244 pn = &(*pn)->next)
1245 ;
1246 *pn = n;
1247 rpath = 1;
1248 }
1249 }
1250
1251 free (dynbuf);
1252 dynbuf = NULL;
1253 }
1254
1255 /* We do not want to include any of the sections in a dynamic
1256 object in the output file. We hack by simply clobbering the
1257 list of sections in the BFD. This could be handled more
1258 cleanly by, say, a new section flag; the existing
1259 SEC_NEVER_LOAD flag is not the one we want, because that one
1260 still implies that the section takes up space in the output
1261 file. */
1262 abfd->sections = NULL;
1263 abfd->section_count = 0;
1264
1265 /* If this is the first dynamic object found in the link, create
1266 the special sections required for dynamic linking. */
1267 if (! elf_hash_table (info)->dynamic_sections_created)
1268 {
1269 if (! elf_link_create_dynamic_sections (abfd, info))
1270 goto error_return;
1271 }
1272
1273 if (add_needed)
1274 {
1275 /* Add a DT_NEEDED entry for this dynamic object. */
1276 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1277 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1278 true, false);
1279 if (strindex == (bfd_size_type) -1)
1280 goto error_return;
1281
1282 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1283 {
1284 asection *sdyn;
1285 Elf_External_Dyn *dyncon, *dynconend;
1286
1287 /* The hash table size did not change, which means that
1288 the dynamic object name was already entered. If we
1289 have already included this dynamic object in the
1290 link, just ignore it. There is no reason to include
1291 a particular dynamic object more than once. */
1292 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1293 ".dynamic");
1294 BFD_ASSERT (sdyn != NULL);
1295
1296 dyncon = (Elf_External_Dyn *) sdyn->contents;
1297 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1298 sdyn->_raw_size);
1299 for (; dyncon < dynconend; dyncon++)
1300 {
1301 Elf_Internal_Dyn dyn;
1302
1303 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1304 &dyn);
1305 if (dyn.d_tag == DT_NEEDED
1306 && dyn.d_un.d_val == strindex)
1307 {
1308 if (buf != NULL)
1309 free (buf);
1310 if (extversym != NULL)
1311 free (extversym);
1312 return true;
1313 }
1314 }
1315 }
1316
1317 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1318 goto error_return;
1319 }
1320
1321 /* Save the SONAME, if there is one, because sometimes the
1322 linker emulation code will need to know it. */
1323 if (*name == '\0')
1324 name = basename (bfd_get_filename (abfd));
1325 elf_dt_name (abfd) = name;
1326 }
1327
1328 if (bfd_seek (abfd,
1329 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1330 SEEK_SET) != 0
1331 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1332 != extsymcount * sizeof (Elf_External_Sym)))
1333 goto error_return;
1334
1335 weaks = NULL;
1336
1337 ever = extversym != NULL ? extversym + extsymoff : NULL;
1338 esymend = buf + extsymcount;
1339 for (esym = buf;
1340 esym < esymend;
1341 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1342 {
1343 Elf_Internal_Sym sym;
1344 int bind;
1345 bfd_vma value;
1346 asection *sec;
1347 flagword flags;
1348 const char *name;
1349 struct elf_link_hash_entry *h;
1350 boolean definition;
1351 boolean size_change_ok, type_change_ok;
1352 boolean new_weakdef;
1353 unsigned int old_alignment;
1354
1355 elf_swap_symbol_in (abfd, esym, &sym);
1356
1357 flags = BSF_NO_FLAGS;
1358 sec = NULL;
1359 value = sym.st_value;
1360 *sym_hash = NULL;
1361
1362 bind = ELF_ST_BIND (sym.st_info);
1363 if (bind == STB_LOCAL)
1364 {
1365 /* This should be impossible, since ELF requires that all
1366 global symbols follow all local symbols, and that sh_info
1367 point to the first global symbol. Unfortunatealy, Irix 5
1368 screws this up. */
1369 continue;
1370 }
1371 else if (bind == STB_GLOBAL)
1372 {
1373 if (sym.st_shndx != SHN_UNDEF
1374 && sym.st_shndx != SHN_COMMON)
1375 flags = BSF_GLOBAL;
1376 }
1377 else if (bind == STB_WEAK)
1378 flags = BSF_WEAK;
1379 else
1380 {
1381 /* Leave it up to the processor backend. */
1382 }
1383
1384 if (sym.st_shndx == SHN_UNDEF)
1385 sec = bfd_und_section_ptr;
1386 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1387 {
1388 sec = section_from_elf_index (abfd, sym.st_shndx);
1389 if (sec == NULL)
1390 sec = bfd_abs_section_ptr;
1391 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1392 value -= sec->vma;
1393 }
1394 else if (sym.st_shndx == SHN_ABS)
1395 sec = bfd_abs_section_ptr;
1396 else if (sym.st_shndx == SHN_COMMON)
1397 {
1398 sec = bfd_com_section_ptr;
1399 /* What ELF calls the size we call the value. What ELF
1400 calls the value we call the alignment. */
1401 value = sym.st_size;
1402 }
1403 else
1404 {
1405 /* Leave it up to the processor backend. */
1406 }
1407
1408 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1409 if (name == (const char *) NULL)
1410 goto error_return;
1411
1412 if (add_symbol_hook)
1413 {
1414 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1415 &value))
1416 goto error_return;
1417
1418 /* The hook function sets the name to NULL if this symbol
1419 should be skipped for some reason. */
1420 if (name == (const char *) NULL)
1421 continue;
1422 }
1423
1424 /* Sanity check that all possibilities were handled. */
1425 if (sec == (asection *) NULL)
1426 {
1427 bfd_set_error (bfd_error_bad_value);
1428 goto error_return;
1429 }
1430
1431 if (bfd_is_und_section (sec)
1432 || bfd_is_com_section (sec))
1433 definition = false;
1434 else
1435 definition = true;
1436
1437 size_change_ok = false;
1438 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1439 old_alignment = 0;
1440 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1441 {
1442 Elf_Internal_Versym iver;
1443 unsigned int vernum = 0;
1444 boolean override;
1445
1446 if (ever != NULL)
1447 {
1448 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1449 vernum = iver.vs_vers & VERSYM_VERSION;
1450
1451 /* If this is a hidden symbol, or if it is not version
1452 1, we append the version name to the symbol name.
1453 However, we do not modify a non-hidden absolute
1454 symbol, because it might be the version symbol
1455 itself. FIXME: What if it isn't? */
1456 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1457 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1458 {
1459 const char *verstr;
1460 int namelen, newlen;
1461 char *newname, *p;
1462
1463 if (sym.st_shndx != SHN_UNDEF)
1464 {
1465 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1466 {
1467 (*_bfd_error_handler)
1468 (_("%s: %s: invalid version %u (max %d)"),
1469 bfd_get_filename (abfd), name, vernum,
1470 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1471 bfd_set_error (bfd_error_bad_value);
1472 goto error_return;
1473 }
1474 else if (vernum > 1)
1475 verstr =
1476 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1477 else
1478 verstr = "";
1479 }
1480 else
1481 {
1482 /* We cannot simply test for the number of
1483 entries in the VERNEED section since the
1484 numbers for the needed versions do not start
1485 at 0. */
1486 Elf_Internal_Verneed *t;
1487
1488 verstr = NULL;
1489 for (t = elf_tdata (abfd)->verref;
1490 t != NULL;
1491 t = t->vn_nextref)
1492 {
1493 Elf_Internal_Vernaux *a;
1494
1495 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1496 {
1497 if (a->vna_other == vernum)
1498 {
1499 verstr = a->vna_nodename;
1500 break;
1501 }
1502 }
1503 if (a != NULL)
1504 break;
1505 }
1506 if (verstr == NULL)
1507 {
1508 (*_bfd_error_handler)
1509 (_("%s: %s: invalid needed version %d"),
1510 bfd_get_filename (abfd), name, vernum);
1511 bfd_set_error (bfd_error_bad_value);
1512 goto error_return;
1513 }
1514 }
1515
1516 namelen = strlen (name);
1517 newlen = namelen + strlen (verstr) + 2;
1518 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1519 ++newlen;
1520
1521 newname = (char *) bfd_alloc (abfd, newlen);
1522 if (newname == NULL)
1523 goto error_return;
1524 strcpy (newname, name);
1525 p = newname + namelen;
1526 *p++ = ELF_VER_CHR;
1527 /* If this is a defined non-hidden version symbol,
1528 we add another @ to the name. This indicates the
1529 default version of the symbol. */
1530 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1531 && sym.st_shndx != SHN_UNDEF)
1532 *p++ = ELF_VER_CHR;
1533 strcpy (p, verstr);
1534
1535 name = newname;
1536 }
1537 }
1538
1539 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1540 sym_hash, &override, &type_change_ok,
1541 &size_change_ok, dt_needed))
1542 goto error_return;
1543
1544 if (override)
1545 definition = false;
1546
1547 h = *sym_hash;
1548 while (h->root.type == bfd_link_hash_indirect
1549 || h->root.type == bfd_link_hash_warning)
1550 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1551
1552 /* Remember the old alignment if this is a common symbol, so
1553 that we don't reduce the alignment later on. We can't
1554 check later, because _bfd_generic_link_add_one_symbol
1555 will set a default for the alignment which we want to
1556 override. */
1557 if (h->root.type == bfd_link_hash_common)
1558 old_alignment = h->root.u.c.p->alignment_power;
1559
1560 if (elf_tdata (abfd)->verdef != NULL
1561 && ! override
1562 && vernum > 1
1563 && definition)
1564 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1565 }
1566
1567 if (! (_bfd_generic_link_add_one_symbol
1568 (info, abfd, name, flags, sec, value, (const char *) NULL,
1569 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1570 goto error_return;
1571
1572 h = *sym_hash;
1573 while (h->root.type == bfd_link_hash_indirect
1574 || h->root.type == bfd_link_hash_warning)
1575 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1576 *sym_hash = h;
1577
1578 new_weakdef = false;
1579 if (dynamic
1580 && definition
1581 && (flags & BSF_WEAK) != 0
1582 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1583 && info->hash->creator->flavour == bfd_target_elf_flavour
1584 && h->weakdef == NULL)
1585 {
1586 /* Keep a list of all weak defined non function symbols from
1587 a dynamic object, using the weakdef field. Later in this
1588 function we will set the weakdef field to the correct
1589 value. We only put non-function symbols from dynamic
1590 objects on this list, because that happens to be the only
1591 time we need to know the normal symbol corresponding to a
1592 weak symbol, and the information is time consuming to
1593 figure out. If the weakdef field is not already NULL,
1594 then this symbol was already defined by some previous
1595 dynamic object, and we will be using that previous
1596 definition anyhow. */
1597
1598 h->weakdef = weaks;
1599 weaks = h;
1600 new_weakdef = true;
1601 }
1602
1603 /* Set the alignment of a common symbol. */
1604 if (sym.st_shndx == SHN_COMMON
1605 && h->root.type == bfd_link_hash_common)
1606 {
1607 unsigned int align;
1608
1609 align = bfd_log2 (sym.st_value);
1610 if (align > old_alignment
1611 /* Permit an alignment power of zero if an alignment of one
1612 is specified and no other alignments have been specified. */
1613 || (sym.st_value == 1 && old_alignment == 0))
1614 h->root.u.c.p->alignment_power = align;
1615 }
1616
1617 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1618 {
1619 int old_flags;
1620 boolean dynsym;
1621 int new_flag;
1622
1623 /* Remember the symbol size and type. */
1624 if (sym.st_size != 0
1625 && (definition || h->size == 0))
1626 {
1627 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1628 (*_bfd_error_handler)
1629 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1630 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1631 bfd_get_filename (abfd));
1632
1633 h->size = sym.st_size;
1634 }
1635
1636 /* If this is a common symbol, then we always want H->SIZE
1637 to be the size of the common symbol. The code just above
1638 won't fix the size if a common symbol becomes larger. We
1639 don't warn about a size change here, because that is
1640 covered by --warn-common. */
1641 if (h->root.type == bfd_link_hash_common)
1642 h->size = h->root.u.c.size;
1643
1644 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1645 && (definition || h->type == STT_NOTYPE))
1646 {
1647 if (h->type != STT_NOTYPE
1648 && h->type != ELF_ST_TYPE (sym.st_info)
1649 && ! type_change_ok)
1650 (*_bfd_error_handler)
1651 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1652 name, h->type, ELF_ST_TYPE (sym.st_info),
1653 bfd_get_filename (abfd));
1654
1655 h->type = ELF_ST_TYPE (sym.st_info);
1656 }
1657
1658 /* If st_other has a processor-specific meaning, specific code
1659 might be needed here. */
1660 if (sym.st_other != 0)
1661 {
1662 /* Combine visibilities, using the most constraining one. */
1663 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1664 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1665
1666 if (symvis && (hvis > symvis || hvis == 0))
1667 h->other = sym.st_other;
1668
1669 /* If neither has visibility, use the st_other of the
1670 definition. This is an arbitrary choice, since the
1671 other bits have no general meaning. */
1672 if (!symvis && !hvis
1673 && (definition || h->other == 0))
1674 h->other = sym.st_other;
1675 }
1676
1677 /* Set a flag in the hash table entry indicating the type of
1678 reference or definition we just found. Keep a count of
1679 the number of dynamic symbols we find. A dynamic symbol
1680 is one which is referenced or defined by both a regular
1681 object and a shared object. */
1682 old_flags = h->elf_link_hash_flags;
1683 dynsym = false;
1684 if (! dynamic)
1685 {
1686 if (! definition)
1687 {
1688 new_flag = ELF_LINK_HASH_REF_REGULAR;
1689 if (bind != STB_WEAK)
1690 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1691 }
1692 else
1693 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1694 if (info->shared
1695 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1696 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1697 dynsym = true;
1698 }
1699 else
1700 {
1701 if (! definition)
1702 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1703 else
1704 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1705 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1706 | ELF_LINK_HASH_REF_REGULAR)) != 0
1707 || (h->weakdef != NULL
1708 && ! new_weakdef
1709 && h->weakdef->dynindx != -1))
1710 dynsym = true;
1711 }
1712
1713 h->elf_link_hash_flags |= new_flag;
1714
1715 /* If this symbol has a version, and it is the default
1716 version, we create an indirect symbol from the default
1717 name to the fully decorated name. This will cause
1718 external references which do not specify a version to be
1719 bound to this version of the symbol. */
1720 if (definition || h->root.type == bfd_link_hash_common)
1721 {
1722 char *p;
1723
1724 p = strchr (name, ELF_VER_CHR);
1725 if (p != NULL && p[1] == ELF_VER_CHR)
1726 {
1727 char *shortname;
1728 struct elf_link_hash_entry *hi;
1729 boolean override;
1730
1731 shortname = bfd_hash_allocate (&info->hash->table,
1732 p - name + 1);
1733 if (shortname == NULL)
1734 goto error_return;
1735 strncpy (shortname, name, p - name);
1736 shortname[p - name] = '\0';
1737
1738 /* We are going to create a new symbol. Merge it
1739 with any existing symbol with this name. For the
1740 purposes of the merge, act as though we were
1741 defining the symbol we just defined, although we
1742 actually going to define an indirect symbol. */
1743 type_change_ok = false;
1744 size_change_ok = false;
1745 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1746 &value, &hi, &override,
1747 &type_change_ok,
1748 &size_change_ok, dt_needed))
1749 goto error_return;
1750
1751 if (! override)
1752 {
1753 if (! (_bfd_generic_link_add_one_symbol
1754 (info, abfd, shortname, BSF_INDIRECT,
1755 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1756 collect, (struct bfd_link_hash_entry **) &hi)))
1757 goto error_return;
1758 }
1759 else
1760 {
1761 /* In this case the symbol named SHORTNAME is
1762 overriding the indirect symbol we want to
1763 add. We were planning on making SHORTNAME an
1764 indirect symbol referring to NAME. SHORTNAME
1765 is the name without a version. NAME is the
1766 fully versioned name, and it is the default
1767 version.
1768
1769 Overriding means that we already saw a
1770 definition for the symbol SHORTNAME in a
1771 regular object, and it is overriding the
1772 symbol defined in the dynamic object.
1773
1774 When this happens, we actually want to change
1775 NAME, the symbol we just added, to refer to
1776 SHORTNAME. This will cause references to
1777 NAME in the shared object to become
1778 references to SHORTNAME in the regular
1779 object. This is what we expect when we
1780 override a function in a shared object: that
1781 the references in the shared object will be
1782 mapped to the definition in the regular
1783 object. */
1784
1785 while (hi->root.type == bfd_link_hash_indirect
1786 || hi->root.type == bfd_link_hash_warning)
1787 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1788
1789 h->root.type = bfd_link_hash_indirect;
1790 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1791 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1792 {
1793 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1794 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1795 if (hi->elf_link_hash_flags
1796 & (ELF_LINK_HASH_REF_REGULAR
1797 | ELF_LINK_HASH_DEF_REGULAR))
1798 {
1799 if (! _bfd_elf_link_record_dynamic_symbol (info,
1800 hi))
1801 goto error_return;
1802 }
1803 }
1804
1805 /* Now set HI to H, so that the following code
1806 will set the other fields correctly. */
1807 hi = h;
1808 }
1809
1810 /* If there is a duplicate definition somewhere,
1811 then HI may not point to an indirect symbol. We
1812 will have reported an error to the user in that
1813 case. */
1814
1815 if (hi->root.type == bfd_link_hash_indirect)
1816 {
1817 struct elf_link_hash_entry *ht;
1818
1819 /* If the symbol became indirect, then we assume
1820 that we have not seen a definition before. */
1821 BFD_ASSERT ((hi->elf_link_hash_flags
1822 & (ELF_LINK_HASH_DEF_DYNAMIC
1823 | ELF_LINK_HASH_DEF_REGULAR))
1824 == 0);
1825
1826 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1827 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1828
1829 /* See if the new flags lead us to realize that
1830 the symbol must be dynamic. */
1831 if (! dynsym)
1832 {
1833 if (! dynamic)
1834 {
1835 if (info->shared
1836 || ((hi->elf_link_hash_flags
1837 & ELF_LINK_HASH_REF_DYNAMIC)
1838 != 0))
1839 dynsym = true;
1840 }
1841 else
1842 {
1843 if ((hi->elf_link_hash_flags
1844 & ELF_LINK_HASH_REF_REGULAR) != 0)
1845 dynsym = true;
1846 }
1847 }
1848 }
1849
1850 /* We also need to define an indirection from the
1851 nondefault version of the symbol. */
1852
1853 shortname = bfd_hash_allocate (&info->hash->table,
1854 strlen (name));
1855 if (shortname == NULL)
1856 goto error_return;
1857 strncpy (shortname, name, p - name);
1858 strcpy (shortname + (p - name), p + 1);
1859
1860 /* Once again, merge with any existing symbol. */
1861 type_change_ok = false;
1862 size_change_ok = false;
1863 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1864 &value, &hi, &override,
1865 &type_change_ok,
1866 &size_change_ok, dt_needed))
1867 goto error_return;
1868
1869 if (override)
1870 {
1871 /* Here SHORTNAME is a versioned name, so we
1872 don't expect to see the type of override we
1873 do in the case above. */
1874 (*_bfd_error_handler)
1875 (_("%s: warning: unexpected redefinition of `%s'"),
1876 bfd_get_filename (abfd), shortname);
1877 }
1878 else
1879 {
1880 if (! (_bfd_generic_link_add_one_symbol
1881 (info, abfd, shortname, BSF_INDIRECT,
1882 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1883 collect, (struct bfd_link_hash_entry **) &hi)))
1884 goto error_return;
1885
1886 /* If there is a duplicate definition somewhere,
1887 then HI may not point to an indirect symbol.
1888 We will have reported an error to the user in
1889 that case. */
1890
1891 if (hi->root.type == bfd_link_hash_indirect)
1892 {
1893 /* If the symbol became indirect, then we
1894 assume that we have not seen a definition
1895 before. */
1896 BFD_ASSERT ((hi->elf_link_hash_flags
1897 & (ELF_LINK_HASH_DEF_DYNAMIC
1898 | ELF_LINK_HASH_DEF_REGULAR))
1899 == 0);
1900
1901 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1902
1903 /* See if the new flags lead us to realize
1904 that the symbol must be dynamic. */
1905 if (! dynsym)
1906 {
1907 if (! dynamic)
1908 {
1909 if (info->shared
1910 || ((hi->elf_link_hash_flags
1911 & ELF_LINK_HASH_REF_DYNAMIC)
1912 != 0))
1913 dynsym = true;
1914 }
1915 else
1916 {
1917 if ((hi->elf_link_hash_flags
1918 & ELF_LINK_HASH_REF_REGULAR) != 0)
1919 dynsym = true;
1920 }
1921 }
1922 }
1923 }
1924 }
1925 }
1926
1927 if (dynsym && h->dynindx == -1)
1928 {
1929 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1930 goto error_return;
1931 if (h->weakdef != NULL
1932 && ! new_weakdef
1933 && h->weakdef->dynindx == -1)
1934 {
1935 if (! _bfd_elf_link_record_dynamic_symbol (info,
1936 h->weakdef))
1937 goto error_return;
1938 }
1939 }
1940 else if (dynsym && h->dynindx != -1)
1941 /* If the symbol already has a dynamic index, but
1942 visibility says it should not be visible, turn it into
1943 a local symbol. */
1944 switch (ELF_ST_VISIBILITY (h->other))
1945 {
1946 case STV_INTERNAL:
1947 case STV_HIDDEN:
1948 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1949 (*bed->elf_backend_hide_symbol) (info, h);
1950 break;
1951 }
1952
1953 if (dt_needed && definition
1954 && (h->elf_link_hash_flags
1955 & ELF_LINK_HASH_REF_REGULAR) != 0)
1956 {
1957 bfd_size_type oldsize;
1958 bfd_size_type strindex;
1959
1960 /* The symbol from a DT_NEEDED object is referenced from
1961 the regular object to create a dynamic executable. We
1962 have to make sure there is a DT_NEEDED entry for it. */
1963
1964 dt_needed = false;
1965 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1966 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
1967 elf_dt_soname (abfd),
1968 true, false);
1969 if (strindex == (bfd_size_type) -1)
1970 goto error_return;
1971
1972 if (oldsize
1973 == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1974 {
1975 asection *sdyn;
1976 Elf_External_Dyn *dyncon, *dynconend;
1977
1978 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1979 ".dynamic");
1980 BFD_ASSERT (sdyn != NULL);
1981
1982 dyncon = (Elf_External_Dyn *) sdyn->contents;
1983 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1984 sdyn->_raw_size);
1985 for (; dyncon < dynconend; dyncon++)
1986 {
1987 Elf_Internal_Dyn dyn;
1988
1989 elf_swap_dyn_in (elf_hash_table (info)->dynobj,
1990 dyncon, &dyn);
1991 BFD_ASSERT (dyn.d_tag != DT_NEEDED ||
1992 dyn.d_un.d_val != strindex);
1993 }
1994 }
1995
1996 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1997 goto error_return;
1998 }
1999 }
2000 }
2001
2002 /* Now set the weakdefs field correctly for all the weak defined
2003 symbols we found. The only way to do this is to search all the
2004 symbols. Since we only need the information for non functions in
2005 dynamic objects, that's the only time we actually put anything on
2006 the list WEAKS. We need this information so that if a regular
2007 object refers to a symbol defined weakly in a dynamic object, the
2008 real symbol in the dynamic object is also put in the dynamic
2009 symbols; we also must arrange for both symbols to point to the
2010 same memory location. We could handle the general case of symbol
2011 aliasing, but a general symbol alias can only be generated in
2012 assembler code, handling it correctly would be very time
2013 consuming, and other ELF linkers don't handle general aliasing
2014 either. */
2015 while (weaks != NULL)
2016 {
2017 struct elf_link_hash_entry *hlook;
2018 asection *slook;
2019 bfd_vma vlook;
2020 struct elf_link_hash_entry **hpp;
2021 struct elf_link_hash_entry **hppend;
2022
2023 hlook = weaks;
2024 weaks = hlook->weakdef;
2025 hlook->weakdef = NULL;
2026
2027 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
2028 || hlook->root.type == bfd_link_hash_defweak
2029 || hlook->root.type == bfd_link_hash_common
2030 || hlook->root.type == bfd_link_hash_indirect);
2031 slook = hlook->root.u.def.section;
2032 vlook = hlook->root.u.def.value;
2033
2034 hpp = elf_sym_hashes (abfd);
2035 hppend = hpp + extsymcount;
2036 for (; hpp < hppend; hpp++)
2037 {
2038 struct elf_link_hash_entry *h;
2039
2040 h = *hpp;
2041 if (h != NULL && h != hlook
2042 && h->root.type == bfd_link_hash_defined
2043 && h->root.u.def.section == slook
2044 && h->root.u.def.value == vlook)
2045 {
2046 hlook->weakdef = h;
2047
2048 /* If the weak definition is in the list of dynamic
2049 symbols, make sure the real definition is put there
2050 as well. */
2051 if (hlook->dynindx != -1
2052 && h->dynindx == -1)
2053 {
2054 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2055 goto error_return;
2056 }
2057
2058 /* If the real definition is in the list of dynamic
2059 symbols, make sure the weak definition is put there
2060 as well. If we don't do this, then the dynamic
2061 loader might not merge the entries for the real
2062 definition and the weak definition. */
2063 if (h->dynindx != -1
2064 && hlook->dynindx == -1)
2065 {
2066 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
2067 goto error_return;
2068 }
2069
2070 break;
2071 }
2072 }
2073 }
2074
2075 if (buf != NULL)
2076 {
2077 free (buf);
2078 buf = NULL;
2079 }
2080
2081 if (extversym != NULL)
2082 {
2083 free (extversym);
2084 extversym = NULL;
2085 }
2086
2087 /* If this object is the same format as the output object, and it is
2088 not a shared library, then let the backend look through the
2089 relocs.
2090
2091 This is required to build global offset table entries and to
2092 arrange for dynamic relocs. It is not required for the
2093 particular common case of linking non PIC code, even when linking
2094 against shared libraries, but unfortunately there is no way of
2095 knowing whether an object file has been compiled PIC or not.
2096 Looking through the relocs is not particularly time consuming.
2097 The problem is that we must either (1) keep the relocs in memory,
2098 which causes the linker to require additional runtime memory or
2099 (2) read the relocs twice from the input file, which wastes time.
2100 This would be a good case for using mmap.
2101
2102 I have no idea how to handle linking PIC code into a file of a
2103 different format. It probably can't be done. */
2104 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2105 if (! dynamic
2106 && abfd->xvec == info->hash->creator
2107 && check_relocs != NULL)
2108 {
2109 asection *o;
2110
2111 for (o = abfd->sections; o != NULL; o = o->next)
2112 {
2113 Elf_Internal_Rela *internal_relocs;
2114 boolean ok;
2115
2116 if ((o->flags & SEC_RELOC) == 0
2117 || o->reloc_count == 0
2118 || ((info->strip == strip_all || info->strip == strip_debugger)
2119 && (o->flags & SEC_DEBUGGING) != 0)
2120 || bfd_is_abs_section (o->output_section))
2121 continue;
2122
2123 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2124 (abfd, o, (PTR) NULL,
2125 (Elf_Internal_Rela *) NULL,
2126 info->keep_memory));
2127 if (internal_relocs == NULL)
2128 goto error_return;
2129
2130 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2131
2132 if (! info->keep_memory)
2133 free (internal_relocs);
2134
2135 if (! ok)
2136 goto error_return;
2137 }
2138 }
2139
2140 /* If this is a non-traditional, non-relocateable link, try to
2141 optimize the handling of the .stab/.stabstr sections. */
2142 if (! dynamic
2143 && ! info->relocateable
2144 && ! info->traditional_format
2145 && info->hash->creator->flavour == bfd_target_elf_flavour
2146 && (info->strip != strip_all && info->strip != strip_debugger))
2147 {
2148 asection *stab, *stabstr;
2149
2150 stab = bfd_get_section_by_name (abfd, ".stab");
2151 if (stab != NULL)
2152 {
2153 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2154
2155 if (stabstr != NULL)
2156 {
2157 struct bfd_elf_section_data *secdata;
2158
2159 secdata = elf_section_data (stab);
2160 if (! _bfd_link_section_stabs (abfd,
2161 &elf_hash_table (info)->stab_info,
2162 stab, stabstr,
2163 &secdata->stab_info))
2164 goto error_return;
2165 }
2166 }
2167 }
2168
2169 if (! info->relocateable && ! dynamic)
2170 {
2171 asection *s;
2172
2173 for (s = abfd->sections; s != NULL; s = s->next)
2174 if ((s->flags & SEC_MERGE)
2175 && ! _bfd_merge_section (abfd,
2176 &elf_hash_table (info)->merge_info,
2177 s, &elf_section_data (s)->merge_info))
2178 goto error_return;
2179 }
2180
2181 return true;
2182
2183 error_return:
2184 if (buf != NULL)
2185 free (buf);
2186 if (dynbuf != NULL)
2187 free (dynbuf);
2188 if (extversym != NULL)
2189 free (extversym);
2190 return false;
2191 }
2192
2193 /* Create some sections which will be filled in with dynamic linking
2194 information. ABFD is an input file which requires dynamic sections
2195 to be created. The dynamic sections take up virtual memory space
2196 when the final executable is run, so we need to create them before
2197 addresses are assigned to the output sections. We work out the
2198 actual contents and size of these sections later. */
2199
2200 boolean
2201 elf_link_create_dynamic_sections (abfd, info)
2202 bfd *abfd;
2203 struct bfd_link_info *info;
2204 {
2205 flagword flags;
2206 register asection *s;
2207 struct elf_link_hash_entry *h;
2208 struct elf_backend_data *bed;
2209
2210 if (elf_hash_table (info)->dynamic_sections_created)
2211 return true;
2212
2213 /* Make sure that all dynamic sections use the same input BFD. */
2214 if (elf_hash_table (info)->dynobj == NULL)
2215 elf_hash_table (info)->dynobj = abfd;
2216 else
2217 abfd = elf_hash_table (info)->dynobj;
2218
2219 /* Note that we set the SEC_IN_MEMORY flag for all of these
2220 sections. */
2221 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2222 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2223
2224 /* A dynamically linked executable has a .interp section, but a
2225 shared library does not. */
2226 if (! info->shared)
2227 {
2228 s = bfd_make_section (abfd, ".interp");
2229 if (s == NULL
2230 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2231 return false;
2232 }
2233
2234 /* Create sections to hold version informations. These are removed
2235 if they are not needed. */
2236 s = bfd_make_section (abfd, ".gnu.version_d");
2237 if (s == NULL
2238 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2239 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2240 return false;
2241
2242 s = bfd_make_section (abfd, ".gnu.version");
2243 if (s == NULL
2244 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2245 || ! bfd_set_section_alignment (abfd, s, 1))
2246 return false;
2247
2248 s = bfd_make_section (abfd, ".gnu.version_r");
2249 if (s == NULL
2250 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2251 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2252 return false;
2253
2254 s = bfd_make_section (abfd, ".dynsym");
2255 if (s == NULL
2256 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2257 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2258 return false;
2259
2260 s = bfd_make_section (abfd, ".dynstr");
2261 if (s == NULL
2262 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2263 return false;
2264
2265 /* Create a strtab to hold the dynamic symbol names. */
2266 if (elf_hash_table (info)->dynstr == NULL)
2267 {
2268 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2269 if (elf_hash_table (info)->dynstr == NULL)
2270 return false;
2271 }
2272
2273 s = bfd_make_section (abfd, ".dynamic");
2274 if (s == NULL
2275 || ! bfd_set_section_flags (abfd, s, flags)
2276 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2277 return false;
2278
2279 /* The special symbol _DYNAMIC is always set to the start of the
2280 .dynamic section. This call occurs before we have processed the
2281 symbols for any dynamic object, so we don't have to worry about
2282 overriding a dynamic definition. We could set _DYNAMIC in a
2283 linker script, but we only want to define it if we are, in fact,
2284 creating a .dynamic section. We don't want to define it if there
2285 is no .dynamic section, since on some ELF platforms the start up
2286 code examines it to decide how to initialize the process. */
2287 h = NULL;
2288 if (! (_bfd_generic_link_add_one_symbol
2289 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2290 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2291 (struct bfd_link_hash_entry **) &h)))
2292 return false;
2293 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2294 h->type = STT_OBJECT;
2295
2296 if (info->shared
2297 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2298 return false;
2299
2300 bed = get_elf_backend_data (abfd);
2301
2302 s = bfd_make_section (abfd, ".hash");
2303 if (s == NULL
2304 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2305 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2306 return false;
2307 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2308
2309 /* Let the backend create the rest of the sections. This lets the
2310 backend set the right flags. The backend will normally create
2311 the .got and .plt sections. */
2312 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2313 return false;
2314
2315 elf_hash_table (info)->dynamic_sections_created = true;
2316
2317 return true;
2318 }
2319
2320 /* Add an entry to the .dynamic table. */
2321
2322 boolean
2323 elf_add_dynamic_entry (info, tag, val)
2324 struct bfd_link_info *info;
2325 bfd_vma tag;
2326 bfd_vma val;
2327 {
2328 Elf_Internal_Dyn dyn;
2329 bfd *dynobj;
2330 asection *s;
2331 size_t newsize;
2332 bfd_byte *newcontents;
2333
2334 dynobj = elf_hash_table (info)->dynobj;
2335
2336 s = bfd_get_section_by_name (dynobj, ".dynamic");
2337 BFD_ASSERT (s != NULL);
2338
2339 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2340 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2341 if (newcontents == NULL)
2342 return false;
2343
2344 dyn.d_tag = tag;
2345 dyn.d_un.d_val = val;
2346 elf_swap_dyn_out (dynobj, &dyn,
2347 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2348
2349 s->_raw_size = newsize;
2350 s->contents = newcontents;
2351
2352 return true;
2353 }
2354
2355 /* Record a new local dynamic symbol. */
2356
2357 boolean
2358 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2359 struct bfd_link_info *info;
2360 bfd *input_bfd;
2361 long input_indx;
2362 {
2363 struct elf_link_local_dynamic_entry *entry;
2364 struct elf_link_hash_table *eht;
2365 struct bfd_strtab_hash *dynstr;
2366 Elf_External_Sym esym;
2367 unsigned long dynstr_index;
2368 char *name;
2369
2370 /* See if the entry exists already. */
2371 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2372 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2373 return true;
2374
2375 entry = (struct elf_link_local_dynamic_entry *)
2376 bfd_alloc (input_bfd, sizeof (*entry));
2377 if (entry == NULL)
2378 return false;
2379
2380 /* Go find the symbol, so that we can find it's name. */
2381 if (bfd_seek (input_bfd,
2382 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2383 + input_indx * sizeof (Elf_External_Sym)),
2384 SEEK_SET) != 0
2385 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2386 != sizeof (Elf_External_Sym)))
2387 return false;
2388 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2389
2390 name = (bfd_elf_string_from_elf_section
2391 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2392 entry->isym.st_name));
2393
2394 dynstr = elf_hash_table (info)->dynstr;
2395 if (dynstr == NULL)
2396 {
2397 /* Create a strtab to hold the dynamic symbol names. */
2398 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2399 if (dynstr == NULL)
2400 return false;
2401 }
2402
2403 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2404 if (dynstr_index == (unsigned long) -1)
2405 return false;
2406 entry->isym.st_name = dynstr_index;
2407
2408 eht = elf_hash_table (info);
2409
2410 entry->next = eht->dynlocal;
2411 eht->dynlocal = entry;
2412 entry->input_bfd = input_bfd;
2413 entry->input_indx = input_indx;
2414 eht->dynsymcount++;
2415
2416 /* Whatever binding the symbol had before, it's now local. */
2417 entry->isym.st_info
2418 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2419
2420 /* The dynindx will be set at the end of size_dynamic_sections. */
2421
2422 return true;
2423 }
2424 \f
2425 /* Read and swap the relocs from the section indicated by SHDR. This
2426 may be either a REL or a RELA section. The relocations are
2427 translated into RELA relocations and stored in INTERNAL_RELOCS,
2428 which should have already been allocated to contain enough space.
2429 The EXTERNAL_RELOCS are a buffer where the external form of the
2430 relocations should be stored.
2431
2432 Returns false if something goes wrong. */
2433
2434 static boolean
2435 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2436 internal_relocs)
2437 bfd *abfd;
2438 Elf_Internal_Shdr *shdr;
2439 PTR external_relocs;
2440 Elf_Internal_Rela *internal_relocs;
2441 {
2442 struct elf_backend_data *bed;
2443
2444 /* If there aren't any relocations, that's OK. */
2445 if (!shdr)
2446 return true;
2447
2448 /* Position ourselves at the start of the section. */
2449 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2450 return false;
2451
2452 /* Read the relocations. */
2453 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2454 != shdr->sh_size)
2455 return false;
2456
2457 bed = get_elf_backend_data (abfd);
2458
2459 /* Convert the external relocations to the internal format. */
2460 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2461 {
2462 Elf_External_Rel *erel;
2463 Elf_External_Rel *erelend;
2464 Elf_Internal_Rela *irela;
2465 Elf_Internal_Rel *irel;
2466
2467 erel = (Elf_External_Rel *) external_relocs;
2468 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2469 irela = internal_relocs;
2470 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2471 * sizeof (Elf_Internal_Rel)));
2472 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2473 {
2474 unsigned char i;
2475
2476 if (bed->s->swap_reloc_in)
2477 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2478 else
2479 elf_swap_reloc_in (abfd, erel, irel);
2480
2481 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2482 {
2483 irela[i].r_offset = irel[i].r_offset;
2484 irela[i].r_info = irel[i].r_info;
2485 irela[i].r_addend = 0;
2486 }
2487 }
2488 }
2489 else
2490 {
2491 Elf_External_Rela *erela;
2492 Elf_External_Rela *erelaend;
2493 Elf_Internal_Rela *irela;
2494
2495 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2496
2497 erela = (Elf_External_Rela *) external_relocs;
2498 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2499 irela = internal_relocs;
2500 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2501 {
2502 if (bed->s->swap_reloca_in)
2503 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2504 else
2505 elf_swap_reloca_in (abfd, erela, irela);
2506 }
2507 }
2508
2509 return true;
2510 }
2511
2512 /* Read and swap the relocs for a section O. They may have been
2513 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2514 not NULL, they are used as buffers to read into. They are known to
2515 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2516 the return value is allocated using either malloc or bfd_alloc,
2517 according to the KEEP_MEMORY argument. If O has two relocation
2518 sections (both REL and RELA relocations), then the REL_HDR
2519 relocations will appear first in INTERNAL_RELOCS, followed by the
2520 REL_HDR2 relocations. */
2521
2522 Elf_Internal_Rela *
2523 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2524 keep_memory)
2525 bfd *abfd;
2526 asection *o;
2527 PTR external_relocs;
2528 Elf_Internal_Rela *internal_relocs;
2529 boolean keep_memory;
2530 {
2531 Elf_Internal_Shdr *rel_hdr;
2532 PTR alloc1 = NULL;
2533 Elf_Internal_Rela *alloc2 = NULL;
2534 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2535
2536 if (elf_section_data (o)->relocs != NULL)
2537 return elf_section_data (o)->relocs;
2538
2539 if (o->reloc_count == 0)
2540 return NULL;
2541
2542 rel_hdr = &elf_section_data (o)->rel_hdr;
2543
2544 if (internal_relocs == NULL)
2545 {
2546 size_t size;
2547
2548 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2549 * sizeof (Elf_Internal_Rela));
2550 if (keep_memory)
2551 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2552 else
2553 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2554 if (internal_relocs == NULL)
2555 goto error_return;
2556 }
2557
2558 if (external_relocs == NULL)
2559 {
2560 size_t size = (size_t) rel_hdr->sh_size;
2561
2562 if (elf_section_data (o)->rel_hdr2)
2563 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2564 alloc1 = (PTR) bfd_malloc (size);
2565 if (alloc1 == NULL)
2566 goto error_return;
2567 external_relocs = alloc1;
2568 }
2569
2570 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2571 external_relocs,
2572 internal_relocs))
2573 goto error_return;
2574 if (!elf_link_read_relocs_from_section
2575 (abfd,
2576 elf_section_data (o)->rel_hdr2,
2577 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2578 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2579 * bed->s->int_rels_per_ext_rel)))
2580 goto error_return;
2581
2582 /* Cache the results for next time, if we can. */
2583 if (keep_memory)
2584 elf_section_data (o)->relocs = internal_relocs;
2585
2586 if (alloc1 != NULL)
2587 free (alloc1);
2588
2589 /* Don't free alloc2, since if it was allocated we are passing it
2590 back (under the name of internal_relocs). */
2591
2592 return internal_relocs;
2593
2594 error_return:
2595 if (alloc1 != NULL)
2596 free (alloc1);
2597 if (alloc2 != NULL)
2598 free (alloc2);
2599 return NULL;
2600 }
2601 \f
2602 /* Record an assignment to a symbol made by a linker script. We need
2603 this in case some dynamic object refers to this symbol. */
2604
2605 /*ARGSUSED*/
2606 boolean
2607 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2608 bfd *output_bfd ATTRIBUTE_UNUSED;
2609 struct bfd_link_info *info;
2610 const char *name;
2611 boolean provide;
2612 {
2613 struct elf_link_hash_entry *h;
2614
2615 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2616 return true;
2617
2618 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2619 if (h == NULL)
2620 return false;
2621
2622 if (h->root.type == bfd_link_hash_new)
2623 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2624
2625 /* If this symbol is being provided by the linker script, and it is
2626 currently defined by a dynamic object, but not by a regular
2627 object, then mark it as undefined so that the generic linker will
2628 force the correct value. */
2629 if (provide
2630 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2631 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2632 h->root.type = bfd_link_hash_undefined;
2633
2634 /* If this symbol is not being provided by the linker script, and it is
2635 currently defined by a dynamic object, but not by a regular object,
2636 then clear out any version information because the symbol will not be
2637 associated with the dynamic object any more. */
2638 if (!provide
2639 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2640 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2641 h->verinfo.verdef = NULL;
2642
2643 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2644
2645 /* When possible, keep the original type of the symbol */
2646 if (h->type == STT_NOTYPE)
2647 h->type = STT_OBJECT;
2648
2649 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2650 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2651 || info->shared)
2652 && h->dynindx == -1)
2653 {
2654 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2655 return false;
2656
2657 /* If this is a weak defined symbol, and we know a corresponding
2658 real symbol from the same dynamic object, make sure the real
2659 symbol is also made into a dynamic symbol. */
2660 if (h->weakdef != NULL
2661 && h->weakdef->dynindx == -1)
2662 {
2663 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2664 return false;
2665 }
2666 }
2667
2668 return true;
2669 }
2670 \f
2671 /* This structure is used to pass information to
2672 elf_link_assign_sym_version. */
2673
2674 struct elf_assign_sym_version_info
2675 {
2676 /* Output BFD. */
2677 bfd *output_bfd;
2678 /* General link information. */
2679 struct bfd_link_info *info;
2680 /* Version tree. */
2681 struct bfd_elf_version_tree *verdefs;
2682 /* Whether we are exporting all dynamic symbols. */
2683 boolean export_dynamic;
2684 /* Whether we had a failure. */
2685 boolean failed;
2686 };
2687
2688 /* This structure is used to pass information to
2689 elf_link_find_version_dependencies. */
2690
2691 struct elf_find_verdep_info
2692 {
2693 /* Output BFD. */
2694 bfd *output_bfd;
2695 /* General link information. */
2696 struct bfd_link_info *info;
2697 /* The number of dependencies. */
2698 unsigned int vers;
2699 /* Whether we had a failure. */
2700 boolean failed;
2701 };
2702
2703 /* Array used to determine the number of hash table buckets to use
2704 based on the number of symbols there are. If there are fewer than
2705 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2706 fewer than 37 we use 17 buckets, and so forth. We never use more
2707 than 32771 buckets. */
2708
2709 static const size_t elf_buckets[] =
2710 {
2711 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2712 16411, 32771, 0
2713 };
2714
2715 /* Compute bucket count for hashing table. We do not use a static set
2716 of possible tables sizes anymore. Instead we determine for all
2717 possible reasonable sizes of the table the outcome (i.e., the
2718 number of collisions etc) and choose the best solution. The
2719 weighting functions are not too simple to allow the table to grow
2720 without bounds. Instead one of the weighting factors is the size.
2721 Therefore the result is always a good payoff between few collisions
2722 (= short chain lengths) and table size. */
2723 static size_t
2724 compute_bucket_count (info)
2725 struct bfd_link_info *info;
2726 {
2727 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2728 size_t best_size = 0;
2729 unsigned long int *hashcodes;
2730 unsigned long int *hashcodesp;
2731 unsigned long int i;
2732
2733 /* Compute the hash values for all exported symbols. At the same
2734 time store the values in an array so that we could use them for
2735 optimizations. */
2736 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2737 * sizeof (unsigned long int));
2738 if (hashcodes == NULL)
2739 return 0;
2740 hashcodesp = hashcodes;
2741
2742 /* Put all hash values in HASHCODES. */
2743 elf_link_hash_traverse (elf_hash_table (info),
2744 elf_collect_hash_codes, &hashcodesp);
2745
2746 /* We have a problem here. The following code to optimize the table
2747 size requires an integer type with more the 32 bits. If
2748 BFD_HOST_U_64_BIT is set we know about such a type. */
2749 #ifdef BFD_HOST_U_64_BIT
2750 if (info->optimize == true)
2751 {
2752 unsigned long int nsyms = hashcodesp - hashcodes;
2753 size_t minsize;
2754 size_t maxsize;
2755 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2756 unsigned long int *counts ;
2757
2758 /* Possible optimization parameters: if we have NSYMS symbols we say
2759 that the hashing table must at least have NSYMS/4 and at most
2760 2*NSYMS buckets. */
2761 minsize = nsyms / 4;
2762 if (minsize == 0)
2763 minsize = 1;
2764 best_size = maxsize = nsyms * 2;
2765
2766 /* Create array where we count the collisions in. We must use bfd_malloc
2767 since the size could be large. */
2768 counts = (unsigned long int *) bfd_malloc (maxsize
2769 * sizeof (unsigned long int));
2770 if (counts == NULL)
2771 {
2772 free (hashcodes);
2773 return 0;
2774 }
2775
2776 /* Compute the "optimal" size for the hash table. The criteria is a
2777 minimal chain length. The minor criteria is (of course) the size
2778 of the table. */
2779 for (i = minsize; i < maxsize; ++i)
2780 {
2781 /* Walk through the array of hashcodes and count the collisions. */
2782 BFD_HOST_U_64_BIT max;
2783 unsigned long int j;
2784 unsigned long int fact;
2785
2786 memset (counts, '\0', i * sizeof (unsigned long int));
2787
2788 /* Determine how often each hash bucket is used. */
2789 for (j = 0; j < nsyms; ++j)
2790 ++counts[hashcodes[j] % i];
2791
2792 /* For the weight function we need some information about the
2793 pagesize on the target. This is information need not be 100%
2794 accurate. Since this information is not available (so far) we
2795 define it here to a reasonable default value. If it is crucial
2796 to have a better value some day simply define this value. */
2797 # ifndef BFD_TARGET_PAGESIZE
2798 # define BFD_TARGET_PAGESIZE (4096)
2799 # endif
2800
2801 /* We in any case need 2 + NSYMS entries for the size values and
2802 the chains. */
2803 max = (2 + nsyms) * (ARCH_SIZE / 8);
2804
2805 # if 1
2806 /* Variant 1: optimize for short chains. We add the squares
2807 of all the chain lengths (which favous many small chain
2808 over a few long chains). */
2809 for (j = 0; j < i; ++j)
2810 max += counts[j] * counts[j];
2811
2812 /* This adds penalties for the overall size of the table. */
2813 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2814 max *= fact * fact;
2815 # else
2816 /* Variant 2: Optimize a lot more for small table. Here we
2817 also add squares of the size but we also add penalties for
2818 empty slots (the +1 term). */
2819 for (j = 0; j < i; ++j)
2820 max += (1 + counts[j]) * (1 + counts[j]);
2821
2822 /* The overall size of the table is considered, but not as
2823 strong as in variant 1, where it is squared. */
2824 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2825 max *= fact;
2826 # endif
2827
2828 /* Compare with current best results. */
2829 if (max < best_chlen)
2830 {
2831 best_chlen = max;
2832 best_size = i;
2833 }
2834 }
2835
2836 free (counts);
2837 }
2838 else
2839 #endif /* defined (BFD_HOST_U_64_BIT) */
2840 {
2841 /* This is the fallback solution if no 64bit type is available or if we
2842 are not supposed to spend much time on optimizations. We select the
2843 bucket count using a fixed set of numbers. */
2844 for (i = 0; elf_buckets[i] != 0; i++)
2845 {
2846 best_size = elf_buckets[i];
2847 if (dynsymcount < elf_buckets[i + 1])
2848 break;
2849 }
2850 }
2851
2852 /* Free the arrays we needed. */
2853 free (hashcodes);
2854
2855 return best_size;
2856 }
2857
2858 /* Set up the sizes and contents of the ELF dynamic sections. This is
2859 called by the ELF linker emulation before_allocation routine. We
2860 must set the sizes of the sections before the linker sets the
2861 addresses of the various sections. */
2862
2863 boolean
2864 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2865 export_dynamic, filter_shlib,
2866 auxiliary_filters, info, sinterpptr,
2867 verdefs)
2868 bfd *output_bfd;
2869 const char *soname;
2870 const char *rpath;
2871 boolean export_dynamic;
2872 const char *filter_shlib;
2873 const char * const *auxiliary_filters;
2874 struct bfd_link_info *info;
2875 asection **sinterpptr;
2876 struct bfd_elf_version_tree *verdefs;
2877 {
2878 bfd_size_type soname_indx;
2879 bfd *dynobj;
2880 struct elf_backend_data *bed;
2881 struct elf_assign_sym_version_info asvinfo;
2882
2883 *sinterpptr = NULL;
2884
2885 soname_indx = (bfd_size_type) -1;
2886
2887 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2888 return true;
2889
2890 /* The backend may have to create some sections regardless of whether
2891 we're dynamic or not. */
2892 bed = get_elf_backend_data (output_bfd);
2893 if (bed->elf_backend_always_size_sections
2894 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2895 return false;
2896
2897 dynobj = elf_hash_table (info)->dynobj;
2898
2899 /* If there were no dynamic objects in the link, there is nothing to
2900 do here. */
2901 if (dynobj == NULL)
2902 return true;
2903
2904 if (elf_hash_table (info)->dynamic_sections_created)
2905 {
2906 struct elf_info_failed eif;
2907 struct elf_link_hash_entry *h;
2908 asection *dynstr;
2909
2910 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2911 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2912
2913 if (soname != NULL)
2914 {
2915 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2916 soname, true, true);
2917 if (soname_indx == (bfd_size_type) -1
2918 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2919 return false;
2920 }
2921
2922 if (info->symbolic)
2923 {
2924 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2925 return false;
2926 info->flags |= DF_SYMBOLIC;
2927 }
2928
2929 if (rpath != NULL)
2930 {
2931 bfd_size_type indx;
2932
2933 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2934 true, true);
2935 if (indx == (bfd_size_type) -1
2936 || ! elf_add_dynamic_entry (info, DT_RPATH, indx)
2937 || (info->new_dtags
2938 && ! elf_add_dynamic_entry (info, DT_RUNPATH, indx)))
2939 return false;
2940 }
2941
2942 if (filter_shlib != NULL)
2943 {
2944 bfd_size_type indx;
2945
2946 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2947 filter_shlib, true, true);
2948 if (indx == (bfd_size_type) -1
2949 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2950 return false;
2951 }
2952
2953 if (auxiliary_filters != NULL)
2954 {
2955 const char * const *p;
2956
2957 for (p = auxiliary_filters; *p != NULL; p++)
2958 {
2959 bfd_size_type indx;
2960
2961 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2962 *p, true, true);
2963 if (indx == (bfd_size_type) -1
2964 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2965 return false;
2966 }
2967 }
2968
2969 eif.info = info;
2970 eif.failed = false;
2971
2972 /* If we are supposed to export all symbols into the dynamic symbol
2973 table (this is not the normal case), then do so. */
2974 if (export_dynamic)
2975 {
2976 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2977 (PTR) &eif);
2978 if (eif.failed)
2979 return false;
2980 }
2981
2982 /* Attach all the symbols to their version information. */
2983 asvinfo.output_bfd = output_bfd;
2984 asvinfo.info = info;
2985 asvinfo.verdefs = verdefs;
2986 asvinfo.export_dynamic = export_dynamic;
2987 asvinfo.failed = false;
2988
2989 elf_link_hash_traverse (elf_hash_table (info),
2990 elf_link_assign_sym_version,
2991 (PTR) &asvinfo);
2992 if (asvinfo.failed)
2993 return false;
2994
2995 /* Find all symbols which were defined in a dynamic object and make
2996 the backend pick a reasonable value for them. */
2997 elf_link_hash_traverse (elf_hash_table (info),
2998 elf_adjust_dynamic_symbol,
2999 (PTR) &eif);
3000 if (eif.failed)
3001 return false;
3002
3003 /* Add some entries to the .dynamic section. We fill in some of the
3004 values later, in elf_bfd_final_link, but we must add the entries
3005 now so that we know the final size of the .dynamic section. */
3006
3007 /* If there are initialization and/or finalization functions to
3008 call then add the corresponding DT_INIT/DT_FINI entries. */
3009 h = (info->init_function
3010 ? elf_link_hash_lookup (elf_hash_table (info),
3011 info->init_function, false,
3012 false, false)
3013 : NULL);
3014 if (h != NULL
3015 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3016 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3017 {
3018 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
3019 return false;
3020 }
3021 h = (info->fini_function
3022 ? elf_link_hash_lookup (elf_hash_table (info),
3023 info->fini_function, false,
3024 false, false)
3025 : NULL);
3026 if (h != NULL
3027 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3028 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3029 {
3030 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
3031 return false;
3032 }
3033
3034 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
3035 /* If .dynstr is excluded from the link, we don't want any of
3036 these tags. Strictly, we should be checking each section
3037 individually; This quick check covers for the case where
3038 someone does a /DISCARD/ : { *(*) }. */
3039 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
3040 {
3041 bfd_size_type strsize;
3042
3043 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3044 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
3045 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
3046 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
3047 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
3048 || ! elf_add_dynamic_entry (info, DT_SYMENT,
3049 sizeof (Elf_External_Sym)))
3050 return false;
3051 }
3052 }
3053
3054 /* The backend must work out the sizes of all the other dynamic
3055 sections. */
3056 if (bed->elf_backend_size_dynamic_sections
3057 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
3058 return false;
3059
3060 if (elf_hash_table (info)->dynamic_sections_created)
3061 {
3062 size_t dynsymcount;
3063 asection *s;
3064 size_t bucketcount = 0;
3065 size_t hash_entry_size;
3066
3067 /* Set up the version definition section. */
3068 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3069 BFD_ASSERT (s != NULL);
3070
3071 /* We may have created additional version definitions if we are
3072 just linking a regular application. */
3073 verdefs = asvinfo.verdefs;
3074
3075 if (verdefs == NULL)
3076 _bfd_strip_section_from_output (info, s);
3077 else
3078 {
3079 unsigned int cdefs;
3080 bfd_size_type size;
3081 struct bfd_elf_version_tree *t;
3082 bfd_byte *p;
3083 Elf_Internal_Verdef def;
3084 Elf_Internal_Verdaux defaux;
3085
3086 cdefs = 0;
3087 size = 0;
3088
3089 /* Make space for the base version. */
3090 size += sizeof (Elf_External_Verdef);
3091 size += sizeof (Elf_External_Verdaux);
3092 ++cdefs;
3093
3094 for (t = verdefs; t != NULL; t = t->next)
3095 {
3096 struct bfd_elf_version_deps *n;
3097
3098 size += sizeof (Elf_External_Verdef);
3099 size += sizeof (Elf_External_Verdaux);
3100 ++cdefs;
3101
3102 for (n = t->deps; n != NULL; n = n->next)
3103 size += sizeof (Elf_External_Verdaux);
3104 }
3105
3106 s->_raw_size = size;
3107 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3108 if (s->contents == NULL && s->_raw_size != 0)
3109 return false;
3110
3111 /* Fill in the version definition section. */
3112
3113 p = s->contents;
3114
3115 def.vd_version = VER_DEF_CURRENT;
3116 def.vd_flags = VER_FLG_BASE;
3117 def.vd_ndx = 1;
3118 def.vd_cnt = 1;
3119 def.vd_aux = sizeof (Elf_External_Verdef);
3120 def.vd_next = (sizeof (Elf_External_Verdef)
3121 + sizeof (Elf_External_Verdaux));
3122
3123 if (soname_indx != (bfd_size_type) -1)
3124 {
3125 def.vd_hash = bfd_elf_hash (soname);
3126 defaux.vda_name = soname_indx;
3127 }
3128 else
3129 {
3130 const char *name;
3131 bfd_size_type indx;
3132
3133 name = output_bfd->filename;
3134 def.vd_hash = bfd_elf_hash (name);
3135 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3136 name, true, false);
3137 if (indx == (bfd_size_type) -1)
3138 return false;
3139 defaux.vda_name = indx;
3140 }
3141 defaux.vda_next = 0;
3142
3143 _bfd_elf_swap_verdef_out (output_bfd, &def,
3144 (Elf_External_Verdef *)p);
3145 p += sizeof (Elf_External_Verdef);
3146 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3147 (Elf_External_Verdaux *) p);
3148 p += sizeof (Elf_External_Verdaux);
3149
3150 for (t = verdefs; t != NULL; t = t->next)
3151 {
3152 unsigned int cdeps;
3153 struct bfd_elf_version_deps *n;
3154 struct elf_link_hash_entry *h;
3155
3156 cdeps = 0;
3157 for (n = t->deps; n != NULL; n = n->next)
3158 ++cdeps;
3159
3160 /* Add a symbol representing this version. */
3161 h = NULL;
3162 if (! (_bfd_generic_link_add_one_symbol
3163 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3164 (bfd_vma) 0, (const char *) NULL, false,
3165 get_elf_backend_data (dynobj)->collect,
3166 (struct bfd_link_hash_entry **) &h)))
3167 return false;
3168 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3169 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3170 h->type = STT_OBJECT;
3171 h->verinfo.vertree = t;
3172
3173 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3174 return false;
3175
3176 def.vd_version = VER_DEF_CURRENT;
3177 def.vd_flags = 0;
3178 if (t->globals == NULL && t->locals == NULL && ! t->used)
3179 def.vd_flags |= VER_FLG_WEAK;
3180 def.vd_ndx = t->vernum + 1;
3181 def.vd_cnt = cdeps + 1;
3182 def.vd_hash = bfd_elf_hash (t->name);
3183 def.vd_aux = sizeof (Elf_External_Verdef);
3184 if (t->next != NULL)
3185 def.vd_next = (sizeof (Elf_External_Verdef)
3186 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3187 else
3188 def.vd_next = 0;
3189
3190 _bfd_elf_swap_verdef_out (output_bfd, &def,
3191 (Elf_External_Verdef *) p);
3192 p += sizeof (Elf_External_Verdef);
3193
3194 defaux.vda_name = h->dynstr_index;
3195 if (t->deps == NULL)
3196 defaux.vda_next = 0;
3197 else
3198 defaux.vda_next = sizeof (Elf_External_Verdaux);
3199 t->name_indx = defaux.vda_name;
3200
3201 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3202 (Elf_External_Verdaux *) p);
3203 p += sizeof (Elf_External_Verdaux);
3204
3205 for (n = t->deps; n != NULL; n = n->next)
3206 {
3207 if (n->version_needed == NULL)
3208 {
3209 /* This can happen if there was an error in the
3210 version script. */
3211 defaux.vda_name = 0;
3212 }
3213 else
3214 defaux.vda_name = n->version_needed->name_indx;
3215 if (n->next == NULL)
3216 defaux.vda_next = 0;
3217 else
3218 defaux.vda_next = sizeof (Elf_External_Verdaux);
3219
3220 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3221 (Elf_External_Verdaux *) p);
3222 p += sizeof (Elf_External_Verdaux);
3223 }
3224 }
3225
3226 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3227 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3228 return false;
3229
3230 elf_tdata (output_bfd)->cverdefs = cdefs;
3231 }
3232
3233 if (info->new_dtags && info->flags)
3234 {
3235 if (! elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
3236 return false;
3237 }
3238
3239 if (info->flags_1)
3240 {
3241 if (! info->shared)
3242 info->flags_1 &= ~ (DF_1_INITFIRST
3243 | DF_1_NODELETE
3244 | DF_1_NOOPEN);
3245 if (! elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
3246 return false;
3247 }
3248
3249 /* Work out the size of the version reference section. */
3250
3251 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3252 BFD_ASSERT (s != NULL);
3253 {
3254 struct elf_find_verdep_info sinfo;
3255
3256 sinfo.output_bfd = output_bfd;
3257 sinfo.info = info;
3258 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3259 if (sinfo.vers == 0)
3260 sinfo.vers = 1;
3261 sinfo.failed = false;
3262
3263 elf_link_hash_traverse (elf_hash_table (info),
3264 elf_link_find_version_dependencies,
3265 (PTR) &sinfo);
3266
3267 if (elf_tdata (output_bfd)->verref == NULL)
3268 _bfd_strip_section_from_output (info, s);
3269 else
3270 {
3271 Elf_Internal_Verneed *t;
3272 unsigned int size;
3273 unsigned int crefs;
3274 bfd_byte *p;
3275
3276 /* Build the version definition section. */
3277 size = 0;
3278 crefs = 0;
3279 for (t = elf_tdata (output_bfd)->verref;
3280 t != NULL;
3281 t = t->vn_nextref)
3282 {
3283 Elf_Internal_Vernaux *a;
3284
3285 size += sizeof (Elf_External_Verneed);
3286 ++crefs;
3287 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3288 size += sizeof (Elf_External_Vernaux);
3289 }
3290
3291 s->_raw_size = size;
3292 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3293 if (s->contents == NULL)
3294 return false;
3295
3296 p = s->contents;
3297 for (t = elf_tdata (output_bfd)->verref;
3298 t != NULL;
3299 t = t->vn_nextref)
3300 {
3301 unsigned int caux;
3302 Elf_Internal_Vernaux *a;
3303 bfd_size_type indx;
3304
3305 caux = 0;
3306 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3307 ++caux;
3308
3309 t->vn_version = VER_NEED_CURRENT;
3310 t->vn_cnt = caux;
3311 if (elf_dt_name (t->vn_bfd) != NULL)
3312 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3313 elf_dt_name (t->vn_bfd),
3314 true, false);
3315 else
3316 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3317 basename (t->vn_bfd->filename),
3318 true, false);
3319 if (indx == (bfd_size_type) -1)
3320 return false;
3321 t->vn_file = indx;
3322 t->vn_aux = sizeof (Elf_External_Verneed);
3323 if (t->vn_nextref == NULL)
3324 t->vn_next = 0;
3325 else
3326 t->vn_next = (sizeof (Elf_External_Verneed)
3327 + caux * sizeof (Elf_External_Vernaux));
3328
3329 _bfd_elf_swap_verneed_out (output_bfd, t,
3330 (Elf_External_Verneed *) p);
3331 p += sizeof (Elf_External_Verneed);
3332
3333 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3334 {
3335 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3336 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3337 a->vna_nodename, true, false);
3338 if (indx == (bfd_size_type) -1)
3339 return false;
3340 a->vna_name = indx;
3341 if (a->vna_nextptr == NULL)
3342 a->vna_next = 0;
3343 else
3344 a->vna_next = sizeof (Elf_External_Vernaux);
3345
3346 _bfd_elf_swap_vernaux_out (output_bfd, a,
3347 (Elf_External_Vernaux *) p);
3348 p += sizeof (Elf_External_Vernaux);
3349 }
3350 }
3351
3352 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3353 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3354 return false;
3355
3356 elf_tdata (output_bfd)->cverrefs = crefs;
3357 }
3358 }
3359
3360 /* Assign dynsym indicies. In a shared library we generate a
3361 section symbol for each output section, which come first.
3362 Next come all of the back-end allocated local dynamic syms,
3363 followed by the rest of the global symbols. */
3364
3365 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3366
3367 /* Work out the size of the symbol version section. */
3368 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3369 BFD_ASSERT (s != NULL);
3370 if (dynsymcount == 0
3371 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3372 {
3373 _bfd_strip_section_from_output (info, s);
3374 /* The DYNSYMCOUNT might have changed if we were going to
3375 output a dynamic symbol table entry for S. */
3376 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3377 }
3378 else
3379 {
3380 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3381 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3382 if (s->contents == NULL)
3383 return false;
3384
3385 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3386 return false;
3387 }
3388
3389 /* Set the size of the .dynsym and .hash sections. We counted
3390 the number of dynamic symbols in elf_link_add_object_symbols.
3391 We will build the contents of .dynsym and .hash when we build
3392 the final symbol table, because until then we do not know the
3393 correct value to give the symbols. We built the .dynstr
3394 section as we went along in elf_link_add_object_symbols. */
3395 s = bfd_get_section_by_name (dynobj, ".dynsym");
3396 BFD_ASSERT (s != NULL);
3397 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3398 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3399 if (s->contents == NULL && s->_raw_size != 0)
3400 return false;
3401
3402 if (dynsymcount != 0)
3403 {
3404 Elf_Internal_Sym isym;
3405
3406 /* The first entry in .dynsym is a dummy symbol. */
3407 isym.st_value = 0;
3408 isym.st_size = 0;
3409 isym.st_name = 0;
3410 isym.st_info = 0;
3411 isym.st_other = 0;
3412 isym.st_shndx = 0;
3413 elf_swap_symbol_out (output_bfd, &isym,
3414 (PTR) (Elf_External_Sym *) s->contents);
3415 }
3416
3417 /* Compute the size of the hashing table. As a side effect this
3418 computes the hash values for all the names we export. */
3419 bucketcount = compute_bucket_count (info);
3420
3421 s = bfd_get_section_by_name (dynobj, ".hash");
3422 BFD_ASSERT (s != NULL);
3423 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3424 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3425 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3426 if (s->contents == NULL)
3427 return false;
3428 memset (s->contents, 0, (size_t) s->_raw_size);
3429
3430 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3431 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3432 s->contents + hash_entry_size);
3433
3434 elf_hash_table (info)->bucketcount = bucketcount;
3435
3436 s = bfd_get_section_by_name (dynobj, ".dynstr");
3437 BFD_ASSERT (s != NULL);
3438 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3439
3440 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3441 return false;
3442 }
3443
3444 return true;
3445 }
3446 \f
3447 /* Fix up the flags for a symbol. This handles various cases which
3448 can only be fixed after all the input files are seen. This is
3449 currently called by both adjust_dynamic_symbol and
3450 assign_sym_version, which is unnecessary but perhaps more robust in
3451 the face of future changes. */
3452
3453 static boolean
3454 elf_fix_symbol_flags (h, eif)
3455 struct elf_link_hash_entry *h;
3456 struct elf_info_failed *eif;
3457 {
3458 /* If this symbol was mentioned in a non-ELF file, try to set
3459 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3460 permit a non-ELF file to correctly refer to a symbol defined in
3461 an ELF dynamic object. */
3462 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3463 {
3464 while (h->root.type == bfd_link_hash_indirect)
3465 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3466
3467 if (h->root.type != bfd_link_hash_defined
3468 && h->root.type != bfd_link_hash_defweak)
3469 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3470 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3471 else
3472 {
3473 if (h->root.u.def.section->owner != NULL
3474 && (bfd_get_flavour (h->root.u.def.section->owner)
3475 == bfd_target_elf_flavour))
3476 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3477 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3478 else
3479 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3480 }
3481
3482 if (h->dynindx == -1
3483 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3484 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3485 {
3486 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3487 {
3488 eif->failed = true;
3489 return false;
3490 }
3491 }
3492 }
3493 else
3494 {
3495 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3496 was first seen in a non-ELF file. Fortunately, if the symbol
3497 was first seen in an ELF file, we're probably OK unless the
3498 symbol was defined in a non-ELF file. Catch that case here.
3499 FIXME: We're still in trouble if the symbol was first seen in
3500 a dynamic object, and then later in a non-ELF regular object. */
3501 if ((h->root.type == bfd_link_hash_defined
3502 || h->root.type == bfd_link_hash_defweak)
3503 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3504 && (h->root.u.def.section->owner != NULL
3505 ? (bfd_get_flavour (h->root.u.def.section->owner)
3506 != bfd_target_elf_flavour)
3507 : (bfd_is_abs_section (h->root.u.def.section)
3508 && (h->elf_link_hash_flags
3509 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3510 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3511 }
3512
3513 /* If this is a final link, and the symbol was defined as a common
3514 symbol in a regular object file, and there was no definition in
3515 any dynamic object, then the linker will have allocated space for
3516 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3517 flag will not have been set. */
3518 if (h->root.type == bfd_link_hash_defined
3519 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3520 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3521 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3522 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3523 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3524
3525 /* If -Bsymbolic was used (which means to bind references to global
3526 symbols to the definition within the shared object), and this
3527 symbol was defined in a regular object, then it actually doesn't
3528 need a PLT entry, and we can accomplish that by forcing it local.
3529 Likewise, if the symbol has hidden or internal visibility.
3530 FIXME: It might be that we also do not need a PLT for other
3531 non-hidden visibilities, but we would have to tell that to the
3532 backend specifically; we can't just clear PLT-related data here. */
3533 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3534 && eif->info->shared
3535 && (eif->info->symbolic
3536 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3537 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3538 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3539 {
3540 struct elf_backend_data *bed;
3541 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
3542 if (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3543 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3544 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3545 (*bed->elf_backend_hide_symbol) (eif->info, h);
3546 }
3547
3548 /* If this is a weak defined symbol in a dynamic object, and we know
3549 the real definition in the dynamic object, copy interesting flags
3550 over to the real definition. */
3551 if (h->weakdef != NULL)
3552 {
3553 struct elf_link_hash_entry *weakdef;
3554
3555 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3556 || h->root.type == bfd_link_hash_defweak);
3557 weakdef = h->weakdef;
3558 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3559 || weakdef->root.type == bfd_link_hash_defweak);
3560 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3561
3562 /* If the real definition is defined by a regular object file,
3563 don't do anything special. See the longer description in
3564 elf_adjust_dynamic_symbol, below. */
3565 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3566 h->weakdef = NULL;
3567 else
3568 weakdef->elf_link_hash_flags |=
3569 (h->elf_link_hash_flags
3570 & (ELF_LINK_HASH_REF_REGULAR
3571 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3572 | ELF_LINK_NON_GOT_REF));
3573 }
3574
3575 return true;
3576 }
3577
3578 /* Make the backend pick a good value for a dynamic symbol. This is
3579 called via elf_link_hash_traverse, and also calls itself
3580 recursively. */
3581
3582 static boolean
3583 elf_adjust_dynamic_symbol (h, data)
3584 struct elf_link_hash_entry *h;
3585 PTR data;
3586 {
3587 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3588 bfd *dynobj;
3589 struct elf_backend_data *bed;
3590
3591 /* Ignore indirect symbols. These are added by the versioning code. */
3592 if (h->root.type == bfd_link_hash_indirect)
3593 return true;
3594
3595 /* Fix the symbol flags. */
3596 if (! elf_fix_symbol_flags (h, eif))
3597 return false;
3598
3599 /* If this symbol does not require a PLT entry, and it is not
3600 defined by a dynamic object, or is not referenced by a regular
3601 object, ignore it. We do have to handle a weak defined symbol,
3602 even if no regular object refers to it, if we decided to add it
3603 to the dynamic symbol table. FIXME: Do we normally need to worry
3604 about symbols which are defined by one dynamic object and
3605 referenced by another one? */
3606 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3607 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3608 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3609 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3610 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3611 {
3612 h->plt.offset = (bfd_vma) -1;
3613 return true;
3614 }
3615
3616 /* If we've already adjusted this symbol, don't do it again. This
3617 can happen via a recursive call. */
3618 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3619 return true;
3620
3621 /* Don't look at this symbol again. Note that we must set this
3622 after checking the above conditions, because we may look at a
3623 symbol once, decide not to do anything, and then get called
3624 recursively later after REF_REGULAR is set below. */
3625 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3626
3627 /* If this is a weak definition, and we know a real definition, and
3628 the real symbol is not itself defined by a regular object file,
3629 then get a good value for the real definition. We handle the
3630 real symbol first, for the convenience of the backend routine.
3631
3632 Note that there is a confusing case here. If the real definition
3633 is defined by a regular object file, we don't get the real symbol
3634 from the dynamic object, but we do get the weak symbol. If the
3635 processor backend uses a COPY reloc, then if some routine in the
3636 dynamic object changes the real symbol, we will not see that
3637 change in the corresponding weak symbol. This is the way other
3638 ELF linkers work as well, and seems to be a result of the shared
3639 library model.
3640
3641 I will clarify this issue. Most SVR4 shared libraries define the
3642 variable _timezone and define timezone as a weak synonym. The
3643 tzset call changes _timezone. If you write
3644 extern int timezone;
3645 int _timezone = 5;
3646 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3647 you might expect that, since timezone is a synonym for _timezone,
3648 the same number will print both times. However, if the processor
3649 backend uses a COPY reloc, then actually timezone will be copied
3650 into your process image, and, since you define _timezone
3651 yourself, _timezone will not. Thus timezone and _timezone will
3652 wind up at different memory locations. The tzset call will set
3653 _timezone, leaving timezone unchanged. */
3654
3655 if (h->weakdef != NULL)
3656 {
3657 /* If we get to this point, we know there is an implicit
3658 reference by a regular object file via the weak symbol H.
3659 FIXME: Is this really true? What if the traversal finds
3660 H->WEAKDEF before it finds H? */
3661 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3662
3663 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3664 return false;
3665 }
3666
3667 /* If a symbol has no type and no size and does not require a PLT
3668 entry, then we are probably about to do the wrong thing here: we
3669 are probably going to create a COPY reloc for an empty object.
3670 This case can arise when a shared object is built with assembly
3671 code, and the assembly code fails to set the symbol type. */
3672 if (h->size == 0
3673 && h->type == STT_NOTYPE
3674 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3675 (*_bfd_error_handler)
3676 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3677 h->root.root.string);
3678
3679 dynobj = elf_hash_table (eif->info)->dynobj;
3680 bed = get_elf_backend_data (dynobj);
3681 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3682 {
3683 eif->failed = true;
3684 return false;
3685 }
3686
3687 return true;
3688 }
3689 \f
3690 /* This routine is used to export all defined symbols into the dynamic
3691 symbol table. It is called via elf_link_hash_traverse. */
3692
3693 static boolean
3694 elf_export_symbol (h, data)
3695 struct elf_link_hash_entry *h;
3696 PTR data;
3697 {
3698 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3699
3700 /* Ignore indirect symbols. These are added by the versioning code. */
3701 if (h->root.type == bfd_link_hash_indirect)
3702 return true;
3703
3704 if (h->dynindx == -1
3705 && (h->elf_link_hash_flags
3706 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3707 {
3708 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3709 {
3710 eif->failed = true;
3711 return false;
3712 }
3713 }
3714
3715 return true;
3716 }
3717 \f
3718 /* Look through the symbols which are defined in other shared
3719 libraries and referenced here. Update the list of version
3720 dependencies. This will be put into the .gnu.version_r section.
3721 This function is called via elf_link_hash_traverse. */
3722
3723 static boolean
3724 elf_link_find_version_dependencies (h, data)
3725 struct elf_link_hash_entry *h;
3726 PTR data;
3727 {
3728 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3729 Elf_Internal_Verneed *t;
3730 Elf_Internal_Vernaux *a;
3731
3732 /* We only care about symbols defined in shared objects with version
3733 information. */
3734 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3735 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3736 || h->dynindx == -1
3737 || h->verinfo.verdef == NULL)
3738 return true;
3739
3740 /* See if we already know about this version. */
3741 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3742 {
3743 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3744 continue;
3745
3746 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3747 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3748 return true;
3749
3750 break;
3751 }
3752
3753 /* This is a new version. Add it to tree we are building. */
3754
3755 if (t == NULL)
3756 {
3757 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3758 if (t == NULL)
3759 {
3760 rinfo->failed = true;
3761 return false;
3762 }
3763
3764 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3765 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3766 elf_tdata (rinfo->output_bfd)->verref = t;
3767 }
3768
3769 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3770
3771 /* Note that we are copying a string pointer here, and testing it
3772 above. If bfd_elf_string_from_elf_section is ever changed to
3773 discard the string data when low in memory, this will have to be
3774 fixed. */
3775 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3776
3777 a->vna_flags = h->verinfo.verdef->vd_flags;
3778 a->vna_nextptr = t->vn_auxptr;
3779
3780 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3781 ++rinfo->vers;
3782
3783 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3784
3785 t->vn_auxptr = a;
3786
3787 return true;
3788 }
3789
3790 /* Figure out appropriate versions for all the symbols. We may not
3791 have the version number script until we have read all of the input
3792 files, so until that point we don't know which symbols should be
3793 local. This function is called via elf_link_hash_traverse. */
3794
3795 static boolean
3796 elf_link_assign_sym_version (h, data)
3797 struct elf_link_hash_entry *h;
3798 PTR data;
3799 {
3800 struct elf_assign_sym_version_info *sinfo =
3801 (struct elf_assign_sym_version_info *) data;
3802 struct bfd_link_info *info = sinfo->info;
3803 struct elf_backend_data *bed;
3804 struct elf_info_failed eif;
3805 char *p;
3806
3807 /* Fix the symbol flags. */
3808 eif.failed = false;
3809 eif.info = info;
3810 if (! elf_fix_symbol_flags (h, &eif))
3811 {
3812 if (eif.failed)
3813 sinfo->failed = true;
3814 return false;
3815 }
3816
3817 /* We only need version numbers for symbols defined in regular
3818 objects. */
3819 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3820 return true;
3821
3822 bed = get_elf_backend_data (sinfo->output_bfd);
3823 p = strchr (h->root.root.string, ELF_VER_CHR);
3824 if (p != NULL && h->verinfo.vertree == NULL)
3825 {
3826 struct bfd_elf_version_tree *t;
3827 boolean hidden;
3828
3829 hidden = true;
3830
3831 /* There are two consecutive ELF_VER_CHR characters if this is
3832 not a hidden symbol. */
3833 ++p;
3834 if (*p == ELF_VER_CHR)
3835 {
3836 hidden = false;
3837 ++p;
3838 }
3839
3840 /* If there is no version string, we can just return out. */
3841 if (*p == '\0')
3842 {
3843 if (hidden)
3844 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3845 return true;
3846 }
3847
3848 /* Look for the version. If we find it, it is no longer weak. */
3849 for (t = sinfo->verdefs; t != NULL; t = t->next)
3850 {
3851 if (strcmp (t->name, p) == 0)
3852 {
3853 int len;
3854 char *alc;
3855 struct bfd_elf_version_expr *d;
3856
3857 len = p - h->root.root.string;
3858 alc = bfd_alloc (sinfo->output_bfd, len);
3859 if (alc == NULL)
3860 return false;
3861 strncpy (alc, h->root.root.string, len - 1);
3862 alc[len - 1] = '\0';
3863 if (alc[len - 2] == ELF_VER_CHR)
3864 alc[len - 2] = '\0';
3865
3866 h->verinfo.vertree = t;
3867 t->used = true;
3868 d = NULL;
3869
3870 if (t->globals != NULL)
3871 {
3872 for (d = t->globals; d != NULL; d = d->next)
3873 if ((*d->match) (d, alc))
3874 break;
3875 }
3876
3877 /* See if there is anything to force this symbol to
3878 local scope. */
3879 if (d == NULL && t->locals != NULL)
3880 {
3881 for (d = t->locals; d != NULL; d = d->next)
3882 {
3883 if ((*d->match) (d, alc))
3884 {
3885 if (h->dynindx != -1
3886 && info->shared
3887 && ! sinfo->export_dynamic)
3888 {
3889 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3890 (*bed->elf_backend_hide_symbol) (info, h);
3891 /* FIXME: The name of the symbol has
3892 already been recorded in the dynamic
3893 string table section. */
3894 }
3895
3896 break;
3897 }
3898 }
3899 }
3900
3901 bfd_release (sinfo->output_bfd, alc);
3902 break;
3903 }
3904 }
3905
3906 /* If we are building an application, we need to create a
3907 version node for this version. */
3908 if (t == NULL && ! info->shared)
3909 {
3910 struct bfd_elf_version_tree **pp;
3911 int version_index;
3912
3913 /* If we aren't going to export this symbol, we don't need
3914 to worry about it. */
3915 if (h->dynindx == -1)
3916 return true;
3917
3918 t = ((struct bfd_elf_version_tree *)
3919 bfd_alloc (sinfo->output_bfd, sizeof *t));
3920 if (t == NULL)
3921 {
3922 sinfo->failed = true;
3923 return false;
3924 }
3925
3926 t->next = NULL;
3927 t->name = p;
3928 t->globals = NULL;
3929 t->locals = NULL;
3930 t->deps = NULL;
3931 t->name_indx = (unsigned int) -1;
3932 t->used = true;
3933
3934 version_index = 1;
3935 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3936 ++version_index;
3937 t->vernum = version_index;
3938
3939 *pp = t;
3940
3941 h->verinfo.vertree = t;
3942 }
3943 else if (t == NULL)
3944 {
3945 /* We could not find the version for a symbol when
3946 generating a shared archive. Return an error. */
3947 (*_bfd_error_handler)
3948 (_("%s: undefined versioned symbol name %s"),
3949 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3950 bfd_set_error (bfd_error_bad_value);
3951 sinfo->failed = true;
3952 return false;
3953 }
3954
3955 if (hidden)
3956 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3957 }
3958
3959 /* If we don't have a version for this symbol, see if we can find
3960 something. */
3961 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3962 {
3963 struct bfd_elf_version_tree *t;
3964 struct bfd_elf_version_tree *deflt;
3965 struct bfd_elf_version_expr *d;
3966
3967 /* See if can find what version this symbol is in. If the
3968 symbol is supposed to be local, then don't actually register
3969 it. */
3970 deflt = NULL;
3971 for (t = sinfo->verdefs; t != NULL; t = t->next)
3972 {
3973 if (t->globals != NULL)
3974 {
3975 for (d = t->globals; d != NULL; d = d->next)
3976 {
3977 if ((*d->match) (d, h->root.root.string))
3978 {
3979 h->verinfo.vertree = t;
3980 break;
3981 }
3982 }
3983
3984 if (d != NULL)
3985 break;
3986 }
3987
3988 if (t->locals != NULL)
3989 {
3990 for (d = t->locals; d != NULL; d = d->next)
3991 {
3992 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3993 deflt = t;
3994 else if ((*d->match) (d, h->root.root.string))
3995 {
3996 h->verinfo.vertree = t;
3997 if (h->dynindx != -1
3998 && info->shared
3999 && ! sinfo->export_dynamic)
4000 {
4001 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4002 (*bed->elf_backend_hide_symbol) (info, h);
4003 /* FIXME: The name of the symbol has already
4004 been recorded in the dynamic string table
4005 section. */
4006 }
4007 break;
4008 }
4009 }
4010
4011 if (d != NULL)
4012 break;
4013 }
4014 }
4015
4016 if (deflt != NULL && h->verinfo.vertree == NULL)
4017 {
4018 h->verinfo.vertree = deflt;
4019 if (h->dynindx != -1
4020 && info->shared
4021 && ! sinfo->export_dynamic)
4022 {
4023 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4024 (*bed->elf_backend_hide_symbol) (info, h);
4025 /* FIXME: The name of the symbol has already been
4026 recorded in the dynamic string table section. */
4027 }
4028 }
4029 }
4030
4031 return true;
4032 }
4033 \f
4034 /* Final phase of ELF linker. */
4035
4036 /* A structure we use to avoid passing large numbers of arguments. */
4037
4038 struct elf_final_link_info
4039 {
4040 /* General link information. */
4041 struct bfd_link_info *info;
4042 /* Output BFD. */
4043 bfd *output_bfd;
4044 /* Symbol string table. */
4045 struct bfd_strtab_hash *symstrtab;
4046 /* .dynsym section. */
4047 asection *dynsym_sec;
4048 /* .hash section. */
4049 asection *hash_sec;
4050 /* symbol version section (.gnu.version). */
4051 asection *symver_sec;
4052 /* Buffer large enough to hold contents of any section. */
4053 bfd_byte *contents;
4054 /* Buffer large enough to hold external relocs of any section. */
4055 PTR external_relocs;
4056 /* Buffer large enough to hold internal relocs of any section. */
4057 Elf_Internal_Rela *internal_relocs;
4058 /* Buffer large enough to hold external local symbols of any input
4059 BFD. */
4060 Elf_External_Sym *external_syms;
4061 /* Buffer large enough to hold internal local symbols of any input
4062 BFD. */
4063 Elf_Internal_Sym *internal_syms;
4064 /* Array large enough to hold a symbol index for each local symbol
4065 of any input BFD. */
4066 long *indices;
4067 /* Array large enough to hold a section pointer for each local
4068 symbol of any input BFD. */
4069 asection **sections;
4070 /* Buffer to hold swapped out symbols. */
4071 Elf_External_Sym *symbuf;
4072 /* Number of swapped out symbols in buffer. */
4073 size_t symbuf_count;
4074 /* Number of symbols which fit in symbuf. */
4075 size_t symbuf_size;
4076 };
4077
4078 static boolean elf_link_output_sym
4079 PARAMS ((struct elf_final_link_info *, const char *,
4080 Elf_Internal_Sym *, asection *));
4081 static boolean elf_link_flush_output_syms
4082 PARAMS ((struct elf_final_link_info *));
4083 static boolean elf_link_output_extsym
4084 PARAMS ((struct elf_link_hash_entry *, PTR));
4085 static boolean elf_link_sec_merge_syms
4086 PARAMS ((struct elf_link_hash_entry *, PTR));
4087 static boolean elf_link_input_bfd
4088 PARAMS ((struct elf_final_link_info *, bfd *));
4089 static boolean elf_reloc_link_order
4090 PARAMS ((bfd *, struct bfd_link_info *, asection *,
4091 struct bfd_link_order *));
4092
4093 /* This struct is used to pass information to elf_link_output_extsym. */
4094
4095 struct elf_outext_info
4096 {
4097 boolean failed;
4098 boolean localsyms;
4099 struct elf_final_link_info *finfo;
4100 };
4101
4102 /* Compute the size of, and allocate space for, REL_HDR which is the
4103 section header for a section containing relocations for O. */
4104
4105 static boolean
4106 elf_link_size_reloc_section (abfd, rel_hdr, o)
4107 bfd *abfd;
4108 Elf_Internal_Shdr *rel_hdr;
4109 asection *o;
4110 {
4111 register struct elf_link_hash_entry **p, **pend;
4112 unsigned reloc_count;
4113
4114 /* Figure out how many relocations there will be. */
4115 if (rel_hdr == &elf_section_data (o)->rel_hdr)
4116 reloc_count = elf_section_data (o)->rel_count;
4117 else
4118 reloc_count = elf_section_data (o)->rel_count2;
4119
4120 /* That allows us to calculate the size of the section. */
4121 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
4122
4123 /* The contents field must last into write_object_contents, so we
4124 allocate it with bfd_alloc rather than malloc. Also since we
4125 cannot be sure that the contents will actually be filled in,
4126 we zero the allocated space. */
4127 rel_hdr->contents = (PTR) bfd_zalloc (abfd, rel_hdr->sh_size);
4128 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
4129 return false;
4130
4131 /* We only allocate one set of hash entries, so we only do it the
4132 first time we are called. */
4133 if (elf_section_data (o)->rel_hashes == NULL)
4134 {
4135 p = ((struct elf_link_hash_entry **)
4136 bfd_malloc (o->reloc_count
4137 * sizeof (struct elf_link_hash_entry *)));
4138 if (p == NULL && o->reloc_count != 0)
4139 return false;
4140
4141 elf_section_data (o)->rel_hashes = p;
4142 pend = p + o->reloc_count;
4143 for (; p < pend; p++)
4144 *p = NULL;
4145 }
4146
4147 return true;
4148 }
4149
4150 /* When performing a relocateable link, the input relocations are
4151 preserved. But, if they reference global symbols, the indices
4152 referenced must be updated. Update all the relocations in
4153 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4154
4155 static void
4156 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4157 bfd *abfd;
4158 Elf_Internal_Shdr *rel_hdr;
4159 unsigned int count;
4160 struct elf_link_hash_entry **rel_hash;
4161 {
4162 unsigned int i;
4163 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4164
4165 for (i = 0; i < count; i++, rel_hash++)
4166 {
4167 if (*rel_hash == NULL)
4168 continue;
4169
4170 BFD_ASSERT ((*rel_hash)->indx >= 0);
4171
4172 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4173 {
4174 Elf_External_Rel *erel;
4175 Elf_Internal_Rel irel;
4176
4177 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4178 if (bed->s->swap_reloc_in)
4179 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, &irel);
4180 else
4181 elf_swap_reloc_in (abfd, erel, &irel);
4182 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
4183 ELF_R_TYPE (irel.r_info));
4184 if (bed->s->swap_reloc_out)
4185 (*bed->s->swap_reloc_out) (abfd, &irel, (bfd_byte *) erel);
4186 else
4187 elf_swap_reloc_out (abfd, &irel, erel);
4188 }
4189 else
4190 {
4191 Elf_External_Rela *erela;
4192 Elf_Internal_Rela irela;
4193
4194 BFD_ASSERT (rel_hdr->sh_entsize
4195 == sizeof (Elf_External_Rela));
4196
4197 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4198 if (bed->s->swap_reloca_in)
4199 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, &irela);
4200 else
4201 elf_swap_reloca_in (abfd, erela, &irela);
4202 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4203 ELF_R_TYPE (irela.r_info));
4204 if (bed->s->swap_reloca_out)
4205 (*bed->s->swap_reloca_out) (abfd, &irela, (bfd_byte *) erela);
4206 else
4207 elf_swap_reloca_out (abfd, &irela, erela);
4208 }
4209 }
4210 }
4211
4212 /* Do the final step of an ELF link. */
4213
4214 boolean
4215 elf_bfd_final_link (abfd, info)
4216 bfd *abfd;
4217 struct bfd_link_info *info;
4218 {
4219 boolean dynamic;
4220 bfd *dynobj;
4221 struct elf_final_link_info finfo;
4222 register asection *o;
4223 register struct bfd_link_order *p;
4224 register bfd *sub;
4225 size_t max_contents_size;
4226 size_t max_external_reloc_size;
4227 size_t max_internal_reloc_count;
4228 size_t max_sym_count;
4229 file_ptr off;
4230 Elf_Internal_Sym elfsym;
4231 unsigned int i;
4232 Elf_Internal_Shdr *symtab_hdr;
4233 Elf_Internal_Shdr *symstrtab_hdr;
4234 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4235 struct elf_outext_info eoinfo;
4236 boolean merged;
4237
4238 if (info->shared)
4239 abfd->flags |= DYNAMIC;
4240
4241 dynamic = elf_hash_table (info)->dynamic_sections_created;
4242 dynobj = elf_hash_table (info)->dynobj;
4243
4244 finfo.info = info;
4245 finfo.output_bfd = abfd;
4246 finfo.symstrtab = elf_stringtab_init ();
4247 if (finfo.symstrtab == NULL)
4248 return false;
4249
4250 if (! dynamic)
4251 {
4252 finfo.dynsym_sec = NULL;
4253 finfo.hash_sec = NULL;
4254 finfo.symver_sec = NULL;
4255 }
4256 else
4257 {
4258 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4259 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4260 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4261 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4262 /* Note that it is OK if symver_sec is NULL. */
4263 }
4264
4265 finfo.contents = NULL;
4266 finfo.external_relocs = NULL;
4267 finfo.internal_relocs = NULL;
4268 finfo.external_syms = NULL;
4269 finfo.internal_syms = NULL;
4270 finfo.indices = NULL;
4271 finfo.sections = NULL;
4272 finfo.symbuf = NULL;
4273 finfo.symbuf_count = 0;
4274
4275 /* Count up the number of relocations we will output for each output
4276 section, so that we know the sizes of the reloc sections. We
4277 also figure out some maximum sizes. */
4278 max_contents_size = 0;
4279 max_external_reloc_size = 0;
4280 max_internal_reloc_count = 0;
4281 max_sym_count = 0;
4282 merged = false;
4283 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4284 {
4285 o->reloc_count = 0;
4286
4287 for (p = o->link_order_head; p != NULL; p = p->next)
4288 {
4289 if (p->type == bfd_section_reloc_link_order
4290 || p->type == bfd_symbol_reloc_link_order)
4291 ++o->reloc_count;
4292 else if (p->type == bfd_indirect_link_order)
4293 {
4294 asection *sec;
4295
4296 sec = p->u.indirect.section;
4297
4298 /* Mark all sections which are to be included in the
4299 link. This will normally be every section. We need
4300 to do this so that we can identify any sections which
4301 the linker has decided to not include. */
4302 sec->linker_mark = true;
4303
4304 if (sec->flags & SEC_MERGE)
4305 merged = true;
4306
4307 if (info->relocateable || info->emitrelocations)
4308 o->reloc_count += sec->reloc_count;
4309
4310 if (sec->_raw_size > max_contents_size)
4311 max_contents_size = sec->_raw_size;
4312 if (sec->_cooked_size > max_contents_size)
4313 max_contents_size = sec->_cooked_size;
4314
4315 /* We are interested in just local symbols, not all
4316 symbols. */
4317 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4318 && (sec->owner->flags & DYNAMIC) == 0)
4319 {
4320 size_t sym_count;
4321
4322 if (elf_bad_symtab (sec->owner))
4323 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4324 / sizeof (Elf_External_Sym));
4325 else
4326 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4327
4328 if (sym_count > max_sym_count)
4329 max_sym_count = sym_count;
4330
4331 if ((sec->flags & SEC_RELOC) != 0)
4332 {
4333 size_t ext_size;
4334
4335 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4336 if (ext_size > max_external_reloc_size)
4337 max_external_reloc_size = ext_size;
4338 if (sec->reloc_count > max_internal_reloc_count)
4339 max_internal_reloc_count = sec->reloc_count;
4340 }
4341 }
4342 }
4343 }
4344
4345 if (o->reloc_count > 0)
4346 o->flags |= SEC_RELOC;
4347 else
4348 {
4349 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4350 set it (this is probably a bug) and if it is set
4351 assign_section_numbers will create a reloc section. */
4352 o->flags &=~ SEC_RELOC;
4353 }
4354
4355 /* If the SEC_ALLOC flag is not set, force the section VMA to
4356 zero. This is done in elf_fake_sections as well, but forcing
4357 the VMA to 0 here will ensure that relocs against these
4358 sections are handled correctly. */
4359 if ((o->flags & SEC_ALLOC) == 0
4360 && ! o->user_set_vma)
4361 o->vma = 0;
4362 }
4363
4364 if (! info->relocateable && merged)
4365 elf_link_hash_traverse (elf_hash_table (info),
4366 elf_link_sec_merge_syms, (PTR) abfd);
4367
4368 /* Figure out the file positions for everything but the symbol table
4369 and the relocs. We set symcount to force assign_section_numbers
4370 to create a symbol table. */
4371 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4372 BFD_ASSERT (! abfd->output_has_begun);
4373 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4374 goto error_return;
4375
4376 /* Figure out how many relocations we will have in each section.
4377 Just using RELOC_COUNT isn't good enough since that doesn't
4378 maintain a separate value for REL vs. RELA relocations. */
4379 if (info->relocateable || info->emitrelocations)
4380 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4381 for (o = sub->sections; o != NULL; o = o->next)
4382 {
4383 asection *output_section;
4384
4385 if (! o->linker_mark)
4386 {
4387 /* This section was omitted from the link. */
4388 continue;
4389 }
4390
4391 output_section = o->output_section;
4392
4393 if (output_section != NULL
4394 && (o->flags & SEC_RELOC) != 0)
4395 {
4396 struct bfd_elf_section_data *esdi
4397 = elf_section_data (o);
4398 struct bfd_elf_section_data *esdo
4399 = elf_section_data (output_section);
4400 unsigned int *rel_count;
4401 unsigned int *rel_count2;
4402
4403 /* We must be careful to add the relocation froms the
4404 input section to the right output count. */
4405 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4406 {
4407 rel_count = &esdo->rel_count;
4408 rel_count2 = &esdo->rel_count2;
4409 }
4410 else
4411 {
4412 rel_count = &esdo->rel_count2;
4413 rel_count2 = &esdo->rel_count;
4414 }
4415
4416 *rel_count += (esdi->rel_hdr.sh_size
4417 / esdi->rel_hdr.sh_entsize);
4418 if (esdi->rel_hdr2)
4419 *rel_count2 += (esdi->rel_hdr2->sh_size
4420 / esdi->rel_hdr2->sh_entsize);
4421 }
4422 }
4423
4424 /* That created the reloc sections. Set their sizes, and assign
4425 them file positions, and allocate some buffers. */
4426 for (o = abfd->sections; o != NULL; o = o->next)
4427 {
4428 if ((o->flags & SEC_RELOC) != 0)
4429 {
4430 if (!elf_link_size_reloc_section (abfd,
4431 &elf_section_data (o)->rel_hdr,
4432 o))
4433 goto error_return;
4434
4435 if (elf_section_data (o)->rel_hdr2
4436 && !elf_link_size_reloc_section (abfd,
4437 elf_section_data (o)->rel_hdr2,
4438 o))
4439 goto error_return;
4440 }
4441
4442 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4443 to count upwards while actually outputting the relocations. */
4444 elf_section_data (o)->rel_count = 0;
4445 elf_section_data (o)->rel_count2 = 0;
4446 }
4447
4448 _bfd_elf_assign_file_positions_for_relocs (abfd);
4449
4450 /* We have now assigned file positions for all the sections except
4451 .symtab and .strtab. We start the .symtab section at the current
4452 file position, and write directly to it. We build the .strtab
4453 section in memory. */
4454 bfd_get_symcount (abfd) = 0;
4455 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4456 /* sh_name is set in prep_headers. */
4457 symtab_hdr->sh_type = SHT_SYMTAB;
4458 symtab_hdr->sh_flags = 0;
4459 symtab_hdr->sh_addr = 0;
4460 symtab_hdr->sh_size = 0;
4461 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4462 /* sh_link is set in assign_section_numbers. */
4463 /* sh_info is set below. */
4464 /* sh_offset is set just below. */
4465 symtab_hdr->sh_addralign = bed->s->file_align;
4466
4467 off = elf_tdata (abfd)->next_file_pos;
4468 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4469
4470 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4471 incorrect. We do not yet know the size of the .symtab section.
4472 We correct next_file_pos below, after we do know the size. */
4473
4474 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4475 continuously seeking to the right position in the file. */
4476 if (! info->keep_memory || max_sym_count < 20)
4477 finfo.symbuf_size = 20;
4478 else
4479 finfo.symbuf_size = max_sym_count;
4480 finfo.symbuf = ((Elf_External_Sym *)
4481 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4482 if (finfo.symbuf == NULL)
4483 goto error_return;
4484
4485 /* Start writing out the symbol table. The first symbol is always a
4486 dummy symbol. */
4487 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4488 {
4489 elfsym.st_value = 0;
4490 elfsym.st_size = 0;
4491 elfsym.st_info = 0;
4492 elfsym.st_other = 0;
4493 elfsym.st_shndx = SHN_UNDEF;
4494 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4495 &elfsym, bfd_und_section_ptr))
4496 goto error_return;
4497 }
4498
4499 #if 0
4500 /* Some standard ELF linkers do this, but we don't because it causes
4501 bootstrap comparison failures. */
4502 /* Output a file symbol for the output file as the second symbol.
4503 We output this even if we are discarding local symbols, although
4504 I'm not sure if this is correct. */
4505 elfsym.st_value = 0;
4506 elfsym.st_size = 0;
4507 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4508 elfsym.st_other = 0;
4509 elfsym.st_shndx = SHN_ABS;
4510 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4511 &elfsym, bfd_abs_section_ptr))
4512 goto error_return;
4513 #endif
4514
4515 /* Output a symbol for each section. We output these even if we are
4516 discarding local symbols, since they are used for relocs. These
4517 symbols have no names. We store the index of each one in the
4518 index field of the section, so that we can find it again when
4519 outputting relocs. */
4520 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4521 {
4522 elfsym.st_size = 0;
4523 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4524 elfsym.st_other = 0;
4525 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4526 {
4527 o = section_from_elf_index (abfd, i);
4528 if (o != NULL)
4529 o->target_index = bfd_get_symcount (abfd);
4530 elfsym.st_shndx = i;
4531 if (info->relocateable || o == NULL)
4532 elfsym.st_value = 0;
4533 else
4534 elfsym.st_value = o->vma;
4535 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4536 &elfsym, o))
4537 goto error_return;
4538 }
4539 }
4540
4541 /* Allocate some memory to hold information read in from the input
4542 files. */
4543 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4544 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4545 finfo.internal_relocs = ((Elf_Internal_Rela *)
4546 bfd_malloc (max_internal_reloc_count
4547 * sizeof (Elf_Internal_Rela)
4548 * bed->s->int_rels_per_ext_rel));
4549 finfo.external_syms = ((Elf_External_Sym *)
4550 bfd_malloc (max_sym_count
4551 * sizeof (Elf_External_Sym)));
4552 finfo.internal_syms = ((Elf_Internal_Sym *)
4553 bfd_malloc (max_sym_count
4554 * sizeof (Elf_Internal_Sym)));
4555 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4556 finfo.sections = ((asection **)
4557 bfd_malloc (max_sym_count * sizeof (asection *)));
4558 if ((finfo.contents == NULL && max_contents_size != 0)
4559 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4560 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4561 || (finfo.external_syms == NULL && max_sym_count != 0)
4562 || (finfo.internal_syms == NULL && max_sym_count != 0)
4563 || (finfo.indices == NULL && max_sym_count != 0)
4564 || (finfo.sections == NULL && max_sym_count != 0))
4565 goto error_return;
4566
4567 /* Since ELF permits relocations to be against local symbols, we
4568 must have the local symbols available when we do the relocations.
4569 Since we would rather only read the local symbols once, and we
4570 would rather not keep them in memory, we handle all the
4571 relocations for a single input file at the same time.
4572
4573 Unfortunately, there is no way to know the total number of local
4574 symbols until we have seen all of them, and the local symbol
4575 indices precede the global symbol indices. This means that when
4576 we are generating relocateable output, and we see a reloc against
4577 a global symbol, we can not know the symbol index until we have
4578 finished examining all the local symbols to see which ones we are
4579 going to output. To deal with this, we keep the relocations in
4580 memory, and don't output them until the end of the link. This is
4581 an unfortunate waste of memory, but I don't see a good way around
4582 it. Fortunately, it only happens when performing a relocateable
4583 link, which is not the common case. FIXME: If keep_memory is set
4584 we could write the relocs out and then read them again; I don't
4585 know how bad the memory loss will be. */
4586
4587 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4588 sub->output_has_begun = false;
4589 for (o = abfd->sections; o != NULL; o = o->next)
4590 {
4591 for (p = o->link_order_head; p != NULL; p = p->next)
4592 {
4593 if (p->type == bfd_indirect_link_order
4594 && (bfd_get_flavour (p->u.indirect.section->owner)
4595 == bfd_target_elf_flavour))
4596 {
4597 sub = p->u.indirect.section->owner;
4598 if (! sub->output_has_begun)
4599 {
4600 if (! elf_link_input_bfd (&finfo, sub))
4601 goto error_return;
4602 sub->output_has_begun = true;
4603 }
4604 }
4605 else if (p->type == bfd_section_reloc_link_order
4606 || p->type == bfd_symbol_reloc_link_order)
4607 {
4608 if (! elf_reloc_link_order (abfd, info, o, p))
4609 goto error_return;
4610 }
4611 else
4612 {
4613 if (! _bfd_default_link_order (abfd, info, o, p))
4614 goto error_return;
4615 }
4616 }
4617 }
4618
4619 /* That wrote out all the local symbols. Finish up the symbol table
4620 with the global symbols. Even if we want to strip everything we
4621 can, we still need to deal with those global symbols that got
4622 converted to local in a version script. */
4623
4624 if (info->shared)
4625 {
4626 /* Output any global symbols that got converted to local in a
4627 version script. We do this in a separate step since ELF
4628 requires all local symbols to appear prior to any global
4629 symbols. FIXME: We should only do this if some global
4630 symbols were, in fact, converted to become local. FIXME:
4631 Will this work correctly with the Irix 5 linker? */
4632 eoinfo.failed = false;
4633 eoinfo.finfo = &finfo;
4634 eoinfo.localsyms = true;
4635 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4636 (PTR) &eoinfo);
4637 if (eoinfo.failed)
4638 return false;
4639 }
4640
4641 /* The sh_info field records the index of the first non local symbol. */
4642 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4643
4644 if (dynamic
4645 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
4646 {
4647 Elf_Internal_Sym sym;
4648 Elf_External_Sym *dynsym =
4649 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4650 long last_local = 0;
4651
4652 /* Write out the section symbols for the output sections. */
4653 if (info->shared)
4654 {
4655 asection *s;
4656
4657 sym.st_size = 0;
4658 sym.st_name = 0;
4659 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4660 sym.st_other = 0;
4661
4662 for (s = abfd->sections; s != NULL; s = s->next)
4663 {
4664 int indx;
4665 indx = elf_section_data (s)->this_idx;
4666 BFD_ASSERT (indx > 0);
4667 sym.st_shndx = indx;
4668 sym.st_value = s->vma;
4669
4670 elf_swap_symbol_out (abfd, &sym,
4671 dynsym + elf_section_data (s)->dynindx);
4672 }
4673
4674 last_local = bfd_count_sections (abfd);
4675 }
4676
4677 /* Write out the local dynsyms. */
4678 if (elf_hash_table (info)->dynlocal)
4679 {
4680 struct elf_link_local_dynamic_entry *e;
4681 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4682 {
4683 asection *s;
4684
4685 sym.st_size = e->isym.st_size;
4686 sym.st_other = e->isym.st_other;
4687
4688 /* Copy the internal symbol as is.
4689 Note that we saved a word of storage and overwrote
4690 the original st_name with the dynstr_index. */
4691 sym = e->isym;
4692
4693 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4694 {
4695 s = bfd_section_from_elf_index (e->input_bfd,
4696 e->isym.st_shndx);
4697
4698 sym.st_shndx =
4699 elf_section_data (s->output_section)->this_idx;
4700 sym.st_value = (s->output_section->vma
4701 + s->output_offset
4702 + e->isym.st_value);
4703 }
4704
4705 if (last_local < e->dynindx)
4706 last_local = e->dynindx;
4707
4708 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4709 }
4710 }
4711
4712 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4713 last_local + 1;
4714 }
4715
4716 /* We get the global symbols from the hash table. */
4717 eoinfo.failed = false;
4718 eoinfo.localsyms = false;
4719 eoinfo.finfo = &finfo;
4720 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4721 (PTR) &eoinfo);
4722 if (eoinfo.failed)
4723 return false;
4724
4725 /* If backend needs to output some symbols not present in the hash
4726 table, do it now. */
4727 if (bed->elf_backend_output_arch_syms)
4728 {
4729 if (! (*bed->elf_backend_output_arch_syms)
4730 (abfd, info, (PTR) &finfo,
4731 (boolean (*) PARAMS ((PTR, const char *,
4732 Elf_Internal_Sym *, asection *)))
4733 elf_link_output_sym))
4734 return false;
4735 }
4736
4737 /* Flush all symbols to the file. */
4738 if (! elf_link_flush_output_syms (&finfo))
4739 return false;
4740
4741 /* Now we know the size of the symtab section. */
4742 off += symtab_hdr->sh_size;
4743
4744 /* Finish up and write out the symbol string table (.strtab)
4745 section. */
4746 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4747 /* sh_name was set in prep_headers. */
4748 symstrtab_hdr->sh_type = SHT_STRTAB;
4749 symstrtab_hdr->sh_flags = 0;
4750 symstrtab_hdr->sh_addr = 0;
4751 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4752 symstrtab_hdr->sh_entsize = 0;
4753 symstrtab_hdr->sh_link = 0;
4754 symstrtab_hdr->sh_info = 0;
4755 /* sh_offset is set just below. */
4756 symstrtab_hdr->sh_addralign = 1;
4757
4758 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4759 elf_tdata (abfd)->next_file_pos = off;
4760
4761 if (bfd_get_symcount (abfd) > 0)
4762 {
4763 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4764 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4765 return false;
4766 }
4767
4768 /* Adjust the relocs to have the correct symbol indices. */
4769 for (o = abfd->sections; o != NULL; o = o->next)
4770 {
4771 if ((o->flags & SEC_RELOC) == 0)
4772 continue;
4773
4774 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4775 elf_section_data (o)->rel_count,
4776 elf_section_data (o)->rel_hashes);
4777 if (elf_section_data (o)->rel_hdr2 != NULL)
4778 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4779 elf_section_data (o)->rel_count2,
4780 (elf_section_data (o)->rel_hashes
4781 + elf_section_data (o)->rel_count));
4782
4783 /* Set the reloc_count field to 0 to prevent write_relocs from
4784 trying to swap the relocs out itself. */
4785 o->reloc_count = 0;
4786 }
4787
4788 /* If we are linking against a dynamic object, or generating a
4789 shared library, finish up the dynamic linking information. */
4790 if (dynamic)
4791 {
4792 Elf_External_Dyn *dyncon, *dynconend;
4793
4794 /* Fix up .dynamic entries. */
4795 o = bfd_get_section_by_name (dynobj, ".dynamic");
4796 BFD_ASSERT (o != NULL);
4797
4798 dyncon = (Elf_External_Dyn *) o->contents;
4799 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4800 for (; dyncon < dynconend; dyncon++)
4801 {
4802 Elf_Internal_Dyn dyn;
4803 const char *name;
4804 unsigned int type;
4805
4806 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4807
4808 switch (dyn.d_tag)
4809 {
4810 default:
4811 break;
4812 case DT_INIT:
4813 name = info->init_function;
4814 goto get_sym;
4815 case DT_FINI:
4816 name = info->fini_function;
4817 get_sym:
4818 {
4819 struct elf_link_hash_entry *h;
4820
4821 h = elf_link_hash_lookup (elf_hash_table (info), name,
4822 false, false, true);
4823 if (h != NULL
4824 && (h->root.type == bfd_link_hash_defined
4825 || h->root.type == bfd_link_hash_defweak))
4826 {
4827 dyn.d_un.d_val = h->root.u.def.value;
4828 o = h->root.u.def.section;
4829 if (o->output_section != NULL)
4830 dyn.d_un.d_val += (o->output_section->vma
4831 + o->output_offset);
4832 else
4833 {
4834 /* The symbol is imported from another shared
4835 library and does not apply to this one. */
4836 dyn.d_un.d_val = 0;
4837 }
4838
4839 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4840 }
4841 }
4842 break;
4843
4844 case DT_HASH:
4845 name = ".hash";
4846 goto get_vma;
4847 case DT_STRTAB:
4848 name = ".dynstr";
4849 goto get_vma;
4850 case DT_SYMTAB:
4851 name = ".dynsym";
4852 goto get_vma;
4853 case DT_VERDEF:
4854 name = ".gnu.version_d";
4855 goto get_vma;
4856 case DT_VERNEED:
4857 name = ".gnu.version_r";
4858 goto get_vma;
4859 case DT_VERSYM:
4860 name = ".gnu.version";
4861 get_vma:
4862 o = bfd_get_section_by_name (abfd, name);
4863 BFD_ASSERT (o != NULL);
4864 dyn.d_un.d_ptr = o->vma;
4865 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4866 break;
4867
4868 case DT_REL:
4869 case DT_RELA:
4870 case DT_RELSZ:
4871 case DT_RELASZ:
4872 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4873 type = SHT_REL;
4874 else
4875 type = SHT_RELA;
4876 dyn.d_un.d_val = 0;
4877 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4878 {
4879 Elf_Internal_Shdr *hdr;
4880
4881 hdr = elf_elfsections (abfd)[i];
4882 if (hdr->sh_type == type
4883 && (hdr->sh_flags & SHF_ALLOC) != 0)
4884 {
4885 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4886 dyn.d_un.d_val += hdr->sh_size;
4887 else
4888 {
4889 if (dyn.d_un.d_val == 0
4890 || hdr->sh_addr < dyn.d_un.d_val)
4891 dyn.d_un.d_val = hdr->sh_addr;
4892 }
4893 }
4894 }
4895 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4896 break;
4897 }
4898 }
4899 }
4900
4901 /* If we have created any dynamic sections, then output them. */
4902 if (dynobj != NULL)
4903 {
4904 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4905 goto error_return;
4906
4907 for (o = dynobj->sections; o != NULL; o = o->next)
4908 {
4909 if ((o->flags & SEC_HAS_CONTENTS) == 0
4910 || o->_raw_size == 0
4911 || o->output_section == bfd_abs_section_ptr)
4912 continue;
4913 if ((o->flags & SEC_LINKER_CREATED) == 0)
4914 {
4915 /* At this point, we are only interested in sections
4916 created by elf_link_create_dynamic_sections. */
4917 continue;
4918 }
4919 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4920 != SHT_STRTAB)
4921 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4922 {
4923 if (! bfd_set_section_contents (abfd, o->output_section,
4924 o->contents, o->output_offset,
4925 o->_raw_size))
4926 goto error_return;
4927 }
4928 else
4929 {
4930 file_ptr off;
4931
4932 /* The contents of the .dynstr section are actually in a
4933 stringtab. */
4934 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4935 if (bfd_seek (abfd, off, SEEK_SET) != 0
4936 || ! _bfd_stringtab_emit (abfd,
4937 elf_hash_table (info)->dynstr))
4938 goto error_return;
4939 }
4940 }
4941 }
4942
4943 /* If we have optimized stabs strings, output them. */
4944 if (elf_hash_table (info)->stab_info != NULL)
4945 {
4946 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4947 goto error_return;
4948 }
4949
4950 if (finfo.symstrtab != NULL)
4951 _bfd_stringtab_free (finfo.symstrtab);
4952 if (finfo.contents != NULL)
4953 free (finfo.contents);
4954 if (finfo.external_relocs != NULL)
4955 free (finfo.external_relocs);
4956 if (finfo.internal_relocs != NULL)
4957 free (finfo.internal_relocs);
4958 if (finfo.external_syms != NULL)
4959 free (finfo.external_syms);
4960 if (finfo.internal_syms != NULL)
4961 free (finfo.internal_syms);
4962 if (finfo.indices != NULL)
4963 free (finfo.indices);
4964 if (finfo.sections != NULL)
4965 free (finfo.sections);
4966 if (finfo.symbuf != NULL)
4967 free (finfo.symbuf);
4968 for (o = abfd->sections; o != NULL; o = o->next)
4969 {
4970 if ((o->flags & SEC_RELOC) != 0
4971 && elf_section_data (o)->rel_hashes != NULL)
4972 free (elf_section_data (o)->rel_hashes);
4973 }
4974
4975 elf_tdata (abfd)->linker = true;
4976
4977 return true;
4978
4979 error_return:
4980 if (finfo.symstrtab != NULL)
4981 _bfd_stringtab_free (finfo.symstrtab);
4982 if (finfo.contents != NULL)
4983 free (finfo.contents);
4984 if (finfo.external_relocs != NULL)
4985 free (finfo.external_relocs);
4986 if (finfo.internal_relocs != NULL)
4987 free (finfo.internal_relocs);
4988 if (finfo.external_syms != NULL)
4989 free (finfo.external_syms);
4990 if (finfo.internal_syms != NULL)
4991 free (finfo.internal_syms);
4992 if (finfo.indices != NULL)
4993 free (finfo.indices);
4994 if (finfo.sections != NULL)
4995 free (finfo.sections);
4996 if (finfo.symbuf != NULL)
4997 free (finfo.symbuf);
4998 for (o = abfd->sections; o != NULL; o = o->next)
4999 {
5000 if ((o->flags & SEC_RELOC) != 0
5001 && elf_section_data (o)->rel_hashes != NULL)
5002 free (elf_section_data (o)->rel_hashes);
5003 }
5004
5005 return false;
5006 }
5007
5008 /* Add a symbol to the output symbol table. */
5009
5010 static boolean
5011 elf_link_output_sym (finfo, name, elfsym, input_sec)
5012 struct elf_final_link_info *finfo;
5013 const char *name;
5014 Elf_Internal_Sym *elfsym;
5015 asection *input_sec;
5016 {
5017 boolean (*output_symbol_hook) PARAMS ((bfd *,
5018 struct bfd_link_info *info,
5019 const char *,
5020 Elf_Internal_Sym *,
5021 asection *));
5022
5023 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
5024 elf_backend_link_output_symbol_hook;
5025 if (output_symbol_hook != NULL)
5026 {
5027 if (! ((*output_symbol_hook)
5028 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
5029 return false;
5030 }
5031
5032 if (name == (const char *) NULL || *name == '\0')
5033 elfsym->st_name = 0;
5034 else if (input_sec->flags & SEC_EXCLUDE)
5035 elfsym->st_name = 0;
5036 else
5037 {
5038 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5039 name, true,
5040 false);
5041 if (elfsym->st_name == (unsigned long) -1)
5042 return false;
5043 }
5044
5045 if (finfo->symbuf_count >= finfo->symbuf_size)
5046 {
5047 if (! elf_link_flush_output_syms (finfo))
5048 return false;
5049 }
5050
5051 elf_swap_symbol_out (finfo->output_bfd, elfsym,
5052 (PTR) (finfo->symbuf + finfo->symbuf_count));
5053 ++finfo->symbuf_count;
5054
5055 ++ bfd_get_symcount (finfo->output_bfd);
5056
5057 return true;
5058 }
5059
5060 /* Flush the output symbols to the file. */
5061
5062 static boolean
5063 elf_link_flush_output_syms (finfo)
5064 struct elf_final_link_info *finfo;
5065 {
5066 if (finfo->symbuf_count > 0)
5067 {
5068 Elf_Internal_Shdr *symtab;
5069
5070 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5071
5072 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
5073 SEEK_SET) != 0
5074 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
5075 sizeof (Elf_External_Sym), finfo->output_bfd)
5076 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
5077 return false;
5078
5079 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
5080
5081 finfo->symbuf_count = 0;
5082 }
5083
5084 return true;
5085 }
5086
5087 /* Adjust all external symbols pointing into SEC_MERGE sections
5088 to reflect the object merging within the sections. */
5089
5090 static boolean
5091 elf_link_sec_merge_syms (h, data)
5092 struct elf_link_hash_entry *h;
5093 PTR data;
5094 {
5095 asection *sec;
5096
5097 if ((h->root.type == bfd_link_hash_defined
5098 || h->root.type == bfd_link_hash_defweak)
5099 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
5100 && elf_section_data (sec)->merge_info)
5101 {
5102 bfd *output_bfd = (bfd *) data;
5103
5104 h->root.u.def.value =
5105 _bfd_merged_section_offset (output_bfd,
5106 &h->root.u.def.section,
5107 elf_section_data (sec)->merge_info,
5108 h->root.u.def.value, (bfd_vma) 0);
5109 }
5110
5111 return true;
5112 }
5113
5114 /* Add an external symbol to the symbol table. This is called from
5115 the hash table traversal routine. When generating a shared object,
5116 we go through the symbol table twice. The first time we output
5117 anything that might have been forced to local scope in a version
5118 script. The second time we output the symbols that are still
5119 global symbols. */
5120
5121 static boolean
5122 elf_link_output_extsym (h, data)
5123 struct elf_link_hash_entry *h;
5124 PTR data;
5125 {
5126 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
5127 struct elf_final_link_info *finfo = eoinfo->finfo;
5128 boolean strip;
5129 Elf_Internal_Sym sym;
5130 asection *input_sec;
5131
5132 /* Decide whether to output this symbol in this pass. */
5133 if (eoinfo->localsyms)
5134 {
5135 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5136 return true;
5137 }
5138 else
5139 {
5140 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5141 return true;
5142 }
5143
5144 /* If we are not creating a shared library, and this symbol is
5145 referenced by a shared library but is not defined anywhere, then
5146 warn that it is undefined. If we do not do this, the runtime
5147 linker will complain that the symbol is undefined when the
5148 program is run. We don't have to worry about symbols that are
5149 referenced by regular files, because we will already have issued
5150 warnings for them. */
5151 if (! finfo->info->relocateable
5152 && ! finfo->info->allow_shlib_undefined
5153 && ! (finfo->info->shared
5154 && !finfo->info->no_undefined)
5155 && h->root.type == bfd_link_hash_undefined
5156 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
5157 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5158 {
5159 if (! ((*finfo->info->callbacks->undefined_symbol)
5160 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
5161 (asection *) NULL, 0, true)))
5162 {
5163 eoinfo->failed = true;
5164 return false;
5165 }
5166 }
5167
5168 /* We don't want to output symbols that have never been mentioned by
5169 a regular file, or that we have been told to strip. However, if
5170 h->indx is set to -2, the symbol is used by a reloc and we must
5171 output it. */
5172 if (h->indx == -2)
5173 strip = false;
5174 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
5175 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
5176 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
5177 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5178 strip = true;
5179 else if (finfo->info->strip == strip_all
5180 || (finfo->info->strip == strip_some
5181 && bfd_hash_lookup (finfo->info->keep_hash,
5182 h->root.root.string,
5183 false, false) == NULL))
5184 strip = true;
5185 else
5186 strip = false;
5187
5188 /* If we're stripping it, and it's not a dynamic symbol, there's
5189 nothing else to do unless it is a forced local symbol. */
5190 if (strip
5191 && h->dynindx == -1
5192 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5193 return true;
5194
5195 sym.st_value = 0;
5196 sym.st_size = h->size;
5197 sym.st_other = h->other;
5198 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5199 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5200 else if (h->root.type == bfd_link_hash_undefweak
5201 || h->root.type == bfd_link_hash_defweak)
5202 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5203 else
5204 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5205
5206 switch (h->root.type)
5207 {
5208 default:
5209 case bfd_link_hash_new:
5210 abort ();
5211 return false;
5212
5213 case bfd_link_hash_undefined:
5214 input_sec = bfd_und_section_ptr;
5215 sym.st_shndx = SHN_UNDEF;
5216 break;
5217
5218 case bfd_link_hash_undefweak:
5219 input_sec = bfd_und_section_ptr;
5220 sym.st_shndx = SHN_UNDEF;
5221 break;
5222
5223 case bfd_link_hash_defined:
5224 case bfd_link_hash_defweak:
5225 {
5226 input_sec = h->root.u.def.section;
5227 if (input_sec->output_section != NULL)
5228 {
5229 sym.st_shndx =
5230 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5231 input_sec->output_section);
5232 if (sym.st_shndx == (unsigned short) -1)
5233 {
5234 (*_bfd_error_handler)
5235 (_("%s: could not find output section %s for input section %s"),
5236 bfd_get_filename (finfo->output_bfd),
5237 input_sec->output_section->name,
5238 input_sec->name);
5239 eoinfo->failed = true;
5240 return false;
5241 }
5242
5243 /* ELF symbols in relocateable files are section relative,
5244 but in nonrelocateable files they are virtual
5245 addresses. */
5246 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5247 if (! finfo->info->relocateable)
5248 sym.st_value += input_sec->output_section->vma;
5249 }
5250 else
5251 {
5252 BFD_ASSERT (input_sec->owner == NULL
5253 || (input_sec->owner->flags & DYNAMIC) != 0);
5254 sym.st_shndx = SHN_UNDEF;
5255 input_sec = bfd_und_section_ptr;
5256 }
5257 }
5258 break;
5259
5260 case bfd_link_hash_common:
5261 input_sec = h->root.u.c.p->section;
5262 sym.st_shndx = SHN_COMMON;
5263 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5264 break;
5265
5266 case bfd_link_hash_indirect:
5267 /* These symbols are created by symbol versioning. They point
5268 to the decorated version of the name. For example, if the
5269 symbol foo@@GNU_1.2 is the default, which should be used when
5270 foo is used with no version, then we add an indirect symbol
5271 foo which points to foo@@GNU_1.2. We ignore these symbols,
5272 since the indirected symbol is already in the hash table. */
5273 return true;
5274
5275 case bfd_link_hash_warning:
5276 /* We can't represent these symbols in ELF, although a warning
5277 symbol may have come from a .gnu.warning.SYMBOL section. We
5278 just put the target symbol in the hash table. If the target
5279 symbol does not really exist, don't do anything. */
5280 if (h->root.u.i.link->type == bfd_link_hash_new)
5281 return true;
5282 return (elf_link_output_extsym
5283 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5284 }
5285
5286 /* Give the processor backend a chance to tweak the symbol value,
5287 and also to finish up anything that needs to be done for this
5288 symbol. */
5289 if ((h->dynindx != -1
5290 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5291 && elf_hash_table (finfo->info)->dynamic_sections_created)
5292 {
5293 struct elf_backend_data *bed;
5294
5295 bed = get_elf_backend_data (finfo->output_bfd);
5296 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5297 (finfo->output_bfd, finfo->info, h, &sym)))
5298 {
5299 eoinfo->failed = true;
5300 return false;
5301 }
5302 }
5303
5304 /* If we are marking the symbol as undefined, and there are no
5305 non-weak references to this symbol from a regular object, then
5306 mark the symbol as weak undefined; if there are non-weak
5307 references, mark the symbol as strong. We can't do this earlier,
5308 because it might not be marked as undefined until the
5309 finish_dynamic_symbol routine gets through with it. */
5310 if (sym.st_shndx == SHN_UNDEF
5311 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5312 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5313 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5314 {
5315 int bindtype;
5316
5317 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5318 bindtype = STB_GLOBAL;
5319 else
5320 bindtype = STB_WEAK;
5321 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5322 }
5323
5324 /* If a symbol is not defined locally, we clear the visibility
5325 field. */
5326 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5327 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5328
5329 /* If this symbol should be put in the .dynsym section, then put it
5330 there now. We have already know the symbol index. We also fill
5331 in the entry in the .hash section. */
5332 if (h->dynindx != -1
5333 && elf_hash_table (finfo->info)->dynamic_sections_created)
5334 {
5335 size_t bucketcount;
5336 size_t bucket;
5337 size_t hash_entry_size;
5338 bfd_byte *bucketpos;
5339 bfd_vma chain;
5340
5341 sym.st_name = h->dynstr_index;
5342
5343 elf_swap_symbol_out (finfo->output_bfd, &sym,
5344 (PTR) (((Elf_External_Sym *)
5345 finfo->dynsym_sec->contents)
5346 + h->dynindx));
5347
5348 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5349 bucket = h->elf_hash_value % bucketcount;
5350 hash_entry_size
5351 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5352 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5353 + (bucket + 2) * hash_entry_size);
5354 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5355 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5356 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5357 ((bfd_byte *) finfo->hash_sec->contents
5358 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5359
5360 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5361 {
5362 Elf_Internal_Versym iversym;
5363
5364 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5365 {
5366 if (h->verinfo.verdef == NULL)
5367 iversym.vs_vers = 0;
5368 else
5369 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5370 }
5371 else
5372 {
5373 if (h->verinfo.vertree == NULL)
5374 iversym.vs_vers = 1;
5375 else
5376 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5377 }
5378
5379 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5380 iversym.vs_vers |= VERSYM_HIDDEN;
5381
5382 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5383 (((Elf_External_Versym *)
5384 finfo->symver_sec->contents)
5385 + h->dynindx));
5386 }
5387 }
5388
5389 /* If we're stripping it, then it was just a dynamic symbol, and
5390 there's nothing else to do. */
5391 if (strip)
5392 return true;
5393
5394 h->indx = bfd_get_symcount (finfo->output_bfd);
5395
5396 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5397 {
5398 eoinfo->failed = true;
5399 return false;
5400 }
5401
5402 return true;
5403 }
5404
5405 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5406 originated from the section given by INPUT_REL_HDR) to the
5407 OUTPUT_BFD. */
5408
5409 static void
5410 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5411 internal_relocs)
5412 bfd *output_bfd;
5413 asection *input_section;
5414 Elf_Internal_Shdr *input_rel_hdr;
5415 Elf_Internal_Rela *internal_relocs;
5416 {
5417 Elf_Internal_Rela *irela;
5418 Elf_Internal_Rela *irelaend;
5419 Elf_Internal_Shdr *output_rel_hdr;
5420 asection *output_section;
5421 unsigned int *rel_countp = NULL;
5422 struct elf_backend_data *bed;
5423
5424 output_section = input_section->output_section;
5425 output_rel_hdr = NULL;
5426
5427 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5428 == input_rel_hdr->sh_entsize)
5429 {
5430 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5431 rel_countp = &elf_section_data (output_section)->rel_count;
5432 }
5433 else if (elf_section_data (output_section)->rel_hdr2
5434 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5435 == input_rel_hdr->sh_entsize))
5436 {
5437 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5438 rel_countp = &elf_section_data (output_section)->rel_count2;
5439 }
5440
5441 BFD_ASSERT (output_rel_hdr != NULL);
5442
5443 bed = get_elf_backend_data (output_bfd);
5444 irela = internal_relocs;
5445 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5446 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5447 {
5448 Elf_External_Rel *erel;
5449
5450 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5451 for (; irela < irelaend; irela++, erel++)
5452 {
5453 Elf_Internal_Rel irel;
5454
5455 irel.r_offset = irela->r_offset;
5456 irel.r_info = irela->r_info;
5457 BFD_ASSERT (irela->r_addend == 0);
5458 if (bed->s->swap_reloc_out)
5459 (*bed->s->swap_reloc_out) (output_bfd, &irel, (PTR) erel);
5460 else
5461 elf_swap_reloc_out (output_bfd, &irel, erel);
5462 }
5463 }
5464 else
5465 {
5466 Elf_External_Rela *erela;
5467
5468 BFD_ASSERT (input_rel_hdr->sh_entsize
5469 == sizeof (Elf_External_Rela));
5470 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5471 for (; irela < irelaend; irela++, erela++)
5472 if (bed->s->swap_reloca_out)
5473 (*bed->s->swap_reloca_out) (output_bfd, irela, (PTR) erela);
5474 else
5475 elf_swap_reloca_out (output_bfd, irela, erela);
5476 }
5477
5478 /* Bump the counter, so that we know where to add the next set of
5479 relocations. */
5480 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5481 }
5482
5483 /* Link an input file into the linker output file. This function
5484 handles all the sections and relocations of the input file at once.
5485 This is so that we only have to read the local symbols once, and
5486 don't have to keep them in memory. */
5487
5488 static boolean
5489 elf_link_input_bfd (finfo, input_bfd)
5490 struct elf_final_link_info *finfo;
5491 bfd *input_bfd;
5492 {
5493 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5494 bfd *, asection *, bfd_byte *,
5495 Elf_Internal_Rela *,
5496 Elf_Internal_Sym *, asection **));
5497 bfd *output_bfd;
5498 Elf_Internal_Shdr *symtab_hdr;
5499 size_t locsymcount;
5500 size_t extsymoff;
5501 Elf_External_Sym *external_syms;
5502 Elf_External_Sym *esym;
5503 Elf_External_Sym *esymend;
5504 Elf_Internal_Sym *isym;
5505 long *pindex;
5506 asection **ppsection;
5507 asection *o;
5508 struct elf_backend_data *bed;
5509
5510 output_bfd = finfo->output_bfd;
5511 bed = get_elf_backend_data (output_bfd);
5512 relocate_section = bed->elf_backend_relocate_section;
5513
5514 /* If this is a dynamic object, we don't want to do anything here:
5515 we don't want the local symbols, and we don't want the section
5516 contents. */
5517 if ((input_bfd->flags & DYNAMIC) != 0)
5518 return true;
5519
5520 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5521 if (elf_bad_symtab (input_bfd))
5522 {
5523 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5524 extsymoff = 0;
5525 }
5526 else
5527 {
5528 locsymcount = symtab_hdr->sh_info;
5529 extsymoff = symtab_hdr->sh_info;
5530 }
5531
5532 /* Read the local symbols. */
5533 if (symtab_hdr->contents != NULL)
5534 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5535 else if (locsymcount == 0)
5536 external_syms = NULL;
5537 else
5538 {
5539 external_syms = finfo->external_syms;
5540 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5541 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5542 locsymcount, input_bfd)
5543 != locsymcount * sizeof (Elf_External_Sym)))
5544 return false;
5545 }
5546
5547 /* Swap in the local symbols and write out the ones which we know
5548 are going into the output file. */
5549 esym = external_syms;
5550 esymend = esym + locsymcount;
5551 isym = finfo->internal_syms;
5552 pindex = finfo->indices;
5553 ppsection = finfo->sections;
5554 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5555 {
5556 asection *isec;
5557 const char *name;
5558 Elf_Internal_Sym osym;
5559
5560 elf_swap_symbol_in (input_bfd, esym, isym);
5561 *pindex = -1;
5562
5563 if (elf_bad_symtab (input_bfd))
5564 {
5565 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5566 {
5567 *ppsection = NULL;
5568 continue;
5569 }
5570 }
5571
5572 name = NULL;
5573 if (isym->st_shndx == SHN_UNDEF)
5574 {
5575 isec = bfd_und_section_ptr;
5576 name = isec->name;
5577 }
5578 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5579 {
5580 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5581 if (isec && elf_section_data (isec)->merge_info
5582 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
5583 isym->st_value =
5584 _bfd_merged_section_offset (output_bfd, &isec,
5585 elf_section_data (isec)->merge_info,
5586 isym->st_value, (bfd_vma) 0);
5587 }
5588 else if (isym->st_shndx == SHN_ABS)
5589 {
5590 isec = bfd_abs_section_ptr;
5591 name = isec->name;
5592 }
5593 else if (isym->st_shndx == SHN_COMMON)
5594 {
5595 isec = bfd_com_section_ptr;
5596 name = isec->name;
5597 }
5598 else
5599 {
5600 /* Who knows? */
5601 isec = NULL;
5602 }
5603
5604 *ppsection = isec;
5605
5606 /* Don't output the first, undefined, symbol. */
5607 if (esym == external_syms)
5608 continue;
5609
5610 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5611 {
5612 asection *ksec;
5613
5614 /* Save away all section symbol values. */
5615 if (isec != NULL)
5616 {
5617 if (name)
5618 {
5619 if (isec->symbol->value != isym->st_value)
5620 (*_bfd_error_handler)
5621 (_("%s: invalid section symbol index 0x%x (%s) ingored"),
5622 bfd_get_filename (input_bfd), isym->st_shndx,
5623 name);
5624 continue;
5625 }
5626 isec->symbol->value = isym->st_value;
5627 }
5628
5629 /* If this is a discarded link-once section symbol, update
5630 it's value to that of the kept section symbol. The
5631 linker will keep the first of any matching link-once
5632 sections, so we should have already seen it's section
5633 symbol. I trust no-one will have the bright idea of
5634 re-ordering the bfd list... */
5635 if (isec != NULL
5636 && (bfd_get_section_flags (input_bfd, isec) & SEC_LINK_ONCE) != 0
5637 && (ksec = isec->kept_section) != NULL)
5638 {
5639 isym->st_value = ksec->symbol->value;
5640
5641 /* That put the value right, but the section info is all
5642 wrong. I hope this works. */
5643 isec->output_offset = ksec->output_offset;
5644 isec->output_section = ksec->output_section;
5645 }
5646
5647 /* We never output section symbols. Instead, we use the
5648 section symbol of the corresponding section in the output
5649 file. */
5650 continue;
5651 }
5652
5653 /* If we are stripping all symbols, we don't want to output this
5654 one. */
5655 if (finfo->info->strip == strip_all)
5656 continue;
5657
5658 /* If we are discarding all local symbols, we don't want to
5659 output this one. If we are generating a relocateable output
5660 file, then some of the local symbols may be required by
5661 relocs; we output them below as we discover that they are
5662 needed. */
5663 if (finfo->info->discard == discard_all)
5664 continue;
5665
5666 /* If this symbol is defined in a section which we are
5667 discarding, we don't need to keep it, but note that
5668 linker_mark is only reliable for sections that have contents.
5669 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5670 as well as linker_mark. */
5671 if (isym->st_shndx > 0
5672 && isym->st_shndx < SHN_LORESERVE
5673 && isec != NULL
5674 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5675 || (! finfo->info->relocateable
5676 && (isec->flags & SEC_EXCLUDE) != 0)))
5677 continue;
5678
5679 /* Get the name of the symbol. */
5680 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5681 isym->st_name);
5682 if (name == NULL)
5683 return false;
5684
5685 /* See if we are discarding symbols with this name. */
5686 if ((finfo->info->strip == strip_some
5687 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5688 == NULL))
5689 || (((finfo->info->discard == discard_sec_merge
5690 && (isec->flags & SEC_MERGE) && ! finfo->info->relocateable)
5691 || finfo->info->discard == discard_l)
5692 && bfd_is_local_label_name (input_bfd, name)))
5693 continue;
5694
5695 /* If we get here, we are going to output this symbol. */
5696
5697 osym = *isym;
5698
5699 /* Adjust the section index for the output file. */
5700 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5701 isec->output_section);
5702 if (osym.st_shndx == (unsigned short) -1)
5703 return false;
5704
5705 *pindex = bfd_get_symcount (output_bfd);
5706
5707 /* ELF symbols in relocateable files are section relative, but
5708 in executable files they are virtual addresses. Note that
5709 this code assumes that all ELF sections have an associated
5710 BFD section with a reasonable value for output_offset; below
5711 we assume that they also have a reasonable value for
5712 output_section. Any special sections must be set up to meet
5713 these requirements. */
5714 osym.st_value += isec->output_offset;
5715 if (! finfo->info->relocateable)
5716 osym.st_value += isec->output_section->vma;
5717
5718 if (! elf_link_output_sym (finfo, name, &osym, isec))
5719 return false;
5720 }
5721
5722 /* Relocate the contents of each section. */
5723 for (o = input_bfd->sections; o != NULL; o = o->next)
5724 {
5725 bfd_byte *contents;
5726
5727 if (! o->linker_mark)
5728 {
5729 /* This section was omitted from the link. */
5730 continue;
5731 }
5732
5733 if ((o->flags & SEC_HAS_CONTENTS) == 0
5734 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5735 continue;
5736
5737 if ((o->flags & SEC_LINKER_CREATED) != 0)
5738 {
5739 /* Section was created by elf_link_create_dynamic_sections
5740 or somesuch. */
5741 continue;
5742 }
5743
5744 /* Get the contents of the section. They have been cached by a
5745 relaxation routine. Note that o is a section in an input
5746 file, so the contents field will not have been set by any of
5747 the routines which work on output files. */
5748 if (elf_section_data (o)->this_hdr.contents != NULL)
5749 contents = elf_section_data (o)->this_hdr.contents;
5750 else
5751 {
5752 contents = finfo->contents;
5753 if (! bfd_get_section_contents (input_bfd, o, contents,
5754 (file_ptr) 0, o->_raw_size))
5755 return false;
5756 }
5757
5758 if ((o->flags & SEC_RELOC) != 0)
5759 {
5760 Elf_Internal_Rela *internal_relocs;
5761
5762 /* Get the swapped relocs. */
5763 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5764 (input_bfd, o, finfo->external_relocs,
5765 finfo->internal_relocs, false));
5766 if (internal_relocs == NULL
5767 && o->reloc_count > 0)
5768 return false;
5769
5770 /* Relocate the section by invoking a back end routine.
5771
5772 The back end routine is responsible for adjusting the
5773 section contents as necessary, and (if using Rela relocs
5774 and generating a relocateable output file) adjusting the
5775 reloc addend as necessary.
5776
5777 The back end routine does not have to worry about setting
5778 the reloc address or the reloc symbol index.
5779
5780 The back end routine is given a pointer to the swapped in
5781 internal symbols, and can access the hash table entries
5782 for the external symbols via elf_sym_hashes (input_bfd).
5783
5784 When generating relocateable output, the back end routine
5785 must handle STB_LOCAL/STT_SECTION symbols specially. The
5786 output symbol is going to be a section symbol
5787 corresponding to the output section, which will require
5788 the addend to be adjusted. */
5789
5790 if (! (*relocate_section) (output_bfd, finfo->info,
5791 input_bfd, o, contents,
5792 internal_relocs,
5793 finfo->internal_syms,
5794 finfo->sections))
5795 return false;
5796
5797 if (finfo->info->relocateable || finfo->info->emitrelocations)
5798 {
5799 Elf_Internal_Rela *irela;
5800 Elf_Internal_Rela *irelaend;
5801 struct elf_link_hash_entry **rel_hash;
5802 Elf_Internal_Shdr *input_rel_hdr;
5803
5804 /* Adjust the reloc addresses and symbol indices. */
5805
5806 irela = internal_relocs;
5807 irelaend =
5808 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5809 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5810 + elf_section_data (o->output_section)->rel_count
5811 + elf_section_data (o->output_section)->rel_count2);
5812 for (; irela < irelaend; irela++, rel_hash++)
5813 {
5814 unsigned long r_symndx;
5815 Elf_Internal_Sym *isym;
5816 asection *sec;
5817
5818 irela->r_offset += o->output_offset;
5819
5820 /* Relocs in an executable have to be virtual addresses. */
5821 if (finfo->info->emitrelocations)
5822 irela->r_offset += o->output_section->vma;
5823
5824 r_symndx = ELF_R_SYM (irela->r_info);
5825
5826 if (r_symndx == 0)
5827 continue;
5828
5829 if (r_symndx >= locsymcount
5830 || (elf_bad_symtab (input_bfd)
5831 && finfo->sections[r_symndx] == NULL))
5832 {
5833 struct elf_link_hash_entry *rh;
5834 long indx;
5835
5836 /* This is a reloc against a global symbol. We
5837 have not yet output all the local symbols, so
5838 we do not know the symbol index of any global
5839 symbol. We set the rel_hash entry for this
5840 reloc to point to the global hash table entry
5841 for this symbol. The symbol index is then
5842 set at the end of elf_bfd_final_link. */
5843 indx = r_symndx - extsymoff;
5844 rh = elf_sym_hashes (input_bfd)[indx];
5845 while (rh->root.type == bfd_link_hash_indirect
5846 || rh->root.type == bfd_link_hash_warning)
5847 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5848
5849 /* Setting the index to -2 tells
5850 elf_link_output_extsym that this symbol is
5851 used by a reloc. */
5852 BFD_ASSERT (rh->indx < 0);
5853 rh->indx = -2;
5854
5855 *rel_hash = rh;
5856
5857 continue;
5858 }
5859
5860 /* This is a reloc against a local symbol. */
5861
5862 *rel_hash = NULL;
5863 isym = finfo->internal_syms + r_symndx;
5864 sec = finfo->sections[r_symndx];
5865 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5866 {
5867 /* I suppose the backend ought to fill in the
5868 section of any STT_SECTION symbol against a
5869 processor specific section. If we have
5870 discarded a section, the output_section will
5871 be the absolute section. */
5872 if (sec != NULL
5873 && (bfd_is_abs_section (sec)
5874 || (sec->output_section != NULL
5875 && bfd_is_abs_section (sec->output_section))))
5876 r_symndx = 0;
5877 else if (sec == NULL || sec->owner == NULL)
5878 {
5879 bfd_set_error (bfd_error_bad_value);
5880 return false;
5881 }
5882 else
5883 {
5884 r_symndx = sec->output_section->target_index;
5885 BFD_ASSERT (r_symndx != 0);
5886 }
5887 }
5888 else
5889 {
5890 if (finfo->indices[r_symndx] == -1)
5891 {
5892 unsigned long link;
5893 const char *name;
5894 asection *osec;
5895
5896 if (finfo->info->strip == strip_all)
5897 {
5898 /* You can't do ld -r -s. */
5899 bfd_set_error (bfd_error_invalid_operation);
5900 return false;
5901 }
5902
5903 /* This symbol was skipped earlier, but
5904 since it is needed by a reloc, we
5905 must output it now. */
5906 link = symtab_hdr->sh_link;
5907 name = bfd_elf_string_from_elf_section (input_bfd,
5908 link,
5909 isym->st_name);
5910 if (name == NULL)
5911 return false;
5912
5913 osec = sec->output_section;
5914 isym->st_shndx =
5915 _bfd_elf_section_from_bfd_section (output_bfd,
5916 osec);
5917 if (isym->st_shndx == (unsigned short) -1)
5918 return false;
5919
5920 isym->st_value += sec->output_offset;
5921 if (! finfo->info->relocateable)
5922 isym->st_value += osec->vma;
5923
5924 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5925
5926 if (! elf_link_output_sym (finfo, name, isym, sec))
5927 return false;
5928 }
5929
5930 r_symndx = finfo->indices[r_symndx];
5931 }
5932
5933 irela->r_info = ELF_R_INFO (r_symndx,
5934 ELF_R_TYPE (irela->r_info));
5935 }
5936
5937 /* Swap out the relocs. */
5938 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5939 elf_link_output_relocs (output_bfd, o,
5940 input_rel_hdr,
5941 internal_relocs);
5942 internal_relocs
5943 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5944 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5945 if (input_rel_hdr)
5946 elf_link_output_relocs (output_bfd, o,
5947 input_rel_hdr,
5948 internal_relocs);
5949 }
5950 }
5951
5952 /* Write out the modified section contents. */
5953 if (elf_section_data (o)->stab_info)
5954 {
5955 if (! (_bfd_write_section_stabs
5956 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5957 o, &elf_section_data (o)->stab_info, contents)))
5958 return false;
5959 }
5960 else if (elf_section_data (o)->merge_info)
5961 {
5962 if (! (_bfd_write_merged_section
5963 (output_bfd, o, elf_section_data (o)->merge_info)))
5964 return false;
5965 }
5966 else
5967 {
5968 if (! (o->flags & SEC_EXCLUDE) &&
5969 ! bfd_set_section_contents (output_bfd, o->output_section,
5970 contents, o->output_offset,
5971 (o->_cooked_size != 0
5972 ? o->_cooked_size
5973 : o->_raw_size)))
5974 return false;
5975 }
5976 }
5977
5978 return true;
5979 }
5980
5981 /* Generate a reloc when linking an ELF file. This is a reloc
5982 requested by the linker, and does come from any input file. This
5983 is used to build constructor and destructor tables when linking
5984 with -Ur. */
5985
5986 static boolean
5987 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5988 bfd *output_bfd;
5989 struct bfd_link_info *info;
5990 asection *output_section;
5991 struct bfd_link_order *link_order;
5992 {
5993 reloc_howto_type *howto;
5994 long indx;
5995 bfd_vma offset;
5996 bfd_vma addend;
5997 struct elf_link_hash_entry **rel_hash_ptr;
5998 Elf_Internal_Shdr *rel_hdr;
5999 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
6000
6001 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
6002 if (howto == NULL)
6003 {
6004 bfd_set_error (bfd_error_bad_value);
6005 return false;
6006 }
6007
6008 addend = link_order->u.reloc.p->addend;
6009
6010 /* Figure out the symbol index. */
6011 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
6012 + elf_section_data (output_section)->rel_count
6013 + elf_section_data (output_section)->rel_count2);
6014 if (link_order->type == bfd_section_reloc_link_order)
6015 {
6016 indx = link_order->u.reloc.p->u.section->target_index;
6017 BFD_ASSERT (indx != 0);
6018 *rel_hash_ptr = NULL;
6019 }
6020 else
6021 {
6022 struct elf_link_hash_entry *h;
6023
6024 /* Treat a reloc against a defined symbol as though it were
6025 actually against the section. */
6026 h = ((struct elf_link_hash_entry *)
6027 bfd_wrapped_link_hash_lookup (output_bfd, info,
6028 link_order->u.reloc.p->u.name,
6029 false, false, true));
6030 if (h != NULL
6031 && (h->root.type == bfd_link_hash_defined
6032 || h->root.type == bfd_link_hash_defweak))
6033 {
6034 asection *section;
6035
6036 section = h->root.u.def.section;
6037 indx = section->output_section->target_index;
6038 *rel_hash_ptr = NULL;
6039 /* It seems that we ought to add the symbol value to the
6040 addend here, but in practice it has already been added
6041 because it was passed to constructor_callback. */
6042 addend += section->output_section->vma + section->output_offset;
6043 }
6044 else if (h != NULL)
6045 {
6046 /* Setting the index to -2 tells elf_link_output_extsym that
6047 this symbol is used by a reloc. */
6048 h->indx = -2;
6049 *rel_hash_ptr = h;
6050 indx = 0;
6051 }
6052 else
6053 {
6054 if (! ((*info->callbacks->unattached_reloc)
6055 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
6056 (asection *) NULL, (bfd_vma) 0)))
6057 return false;
6058 indx = 0;
6059 }
6060 }
6061
6062 /* If this is an inplace reloc, we must write the addend into the
6063 object file. */
6064 if (howto->partial_inplace && addend != 0)
6065 {
6066 bfd_size_type size;
6067 bfd_reloc_status_type rstat;
6068 bfd_byte *buf;
6069 boolean ok;
6070
6071 size = bfd_get_reloc_size (howto);
6072 buf = (bfd_byte *) bfd_zmalloc (size);
6073 if (buf == (bfd_byte *) NULL)
6074 return false;
6075 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
6076 switch (rstat)
6077 {
6078 case bfd_reloc_ok:
6079 break;
6080 default:
6081 case bfd_reloc_outofrange:
6082 abort ();
6083 case bfd_reloc_overflow:
6084 if (! ((*info->callbacks->reloc_overflow)
6085 (info,
6086 (link_order->type == bfd_section_reloc_link_order
6087 ? bfd_section_name (output_bfd,
6088 link_order->u.reloc.p->u.section)
6089 : link_order->u.reloc.p->u.name),
6090 howto->name, addend, (bfd *) NULL, (asection *) NULL,
6091 (bfd_vma) 0)))
6092 {
6093 free (buf);
6094 return false;
6095 }
6096 break;
6097 }
6098 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
6099 (file_ptr) link_order->offset, size);
6100 free (buf);
6101 if (! ok)
6102 return false;
6103 }
6104
6105 /* The address of a reloc is relative to the section in a
6106 relocateable file, and is a virtual address in an executable
6107 file. */
6108 offset = link_order->offset;
6109 if (! info->relocateable)
6110 offset += output_section->vma;
6111
6112 rel_hdr = &elf_section_data (output_section)->rel_hdr;
6113
6114 if (rel_hdr->sh_type == SHT_REL)
6115 {
6116 Elf_Internal_Rel irel;
6117 Elf_External_Rel *erel;
6118
6119 irel.r_offset = offset;
6120 irel.r_info = ELF_R_INFO (indx, howto->type);
6121 erel = ((Elf_External_Rel *) rel_hdr->contents
6122 + elf_section_data (output_section)->rel_count);
6123 if (bed->s->swap_reloc_out)
6124 (*bed->s->swap_reloc_out) (output_bfd, &irel, (bfd_byte *) erel);
6125 else
6126 elf_swap_reloc_out (output_bfd, &irel, erel);
6127 }
6128 else
6129 {
6130 Elf_Internal_Rela irela;
6131 Elf_External_Rela *erela;
6132
6133 irela.r_offset = offset;
6134 irela.r_info = ELF_R_INFO (indx, howto->type);
6135 irela.r_addend = addend;
6136 erela = ((Elf_External_Rela *) rel_hdr->contents
6137 + elf_section_data (output_section)->rel_count);
6138 if (bed->s->swap_reloca_out)
6139 (*bed->s->swap_reloca_out) (output_bfd, &irela, (bfd_byte *) erela);
6140 else
6141 elf_swap_reloca_out (output_bfd, &irela, erela);
6142 }
6143
6144 ++elf_section_data (output_section)->rel_count;
6145
6146 return true;
6147 }
6148 \f
6149 /* Allocate a pointer to live in a linker created section. */
6150
6151 boolean
6152 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6153 bfd *abfd;
6154 struct bfd_link_info *info;
6155 elf_linker_section_t *lsect;
6156 struct elf_link_hash_entry *h;
6157 const Elf_Internal_Rela *rel;
6158 {
6159 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6160 elf_linker_section_pointers_t *linker_section_ptr;
6161 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6162
6163 BFD_ASSERT (lsect != NULL);
6164
6165 /* Is this a global symbol? */
6166 if (h != NULL)
6167 {
6168 /* Has this symbol already been allocated, if so, our work is done */
6169 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6170 rel->r_addend,
6171 lsect->which))
6172 return true;
6173
6174 ptr_linker_section_ptr = &h->linker_section_pointer;
6175 /* Make sure this symbol is output as a dynamic symbol. */
6176 if (h->dynindx == -1)
6177 {
6178 if (! elf_link_record_dynamic_symbol (info, h))
6179 return false;
6180 }
6181
6182 if (lsect->rel_section)
6183 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6184 }
6185
6186 else /* Allocation of a pointer to a local symbol */
6187 {
6188 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6189
6190 /* Allocate a table to hold the local symbols if first time */
6191 if (!ptr)
6192 {
6193 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6194 register unsigned int i;
6195
6196 ptr = (elf_linker_section_pointers_t **)
6197 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6198
6199 if (!ptr)
6200 return false;
6201
6202 elf_local_ptr_offsets (abfd) = ptr;
6203 for (i = 0; i < num_symbols; i++)
6204 ptr[i] = (elf_linker_section_pointers_t *)0;
6205 }
6206
6207 /* Has this symbol already been allocated, if so, our work is done */
6208 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6209 rel->r_addend,
6210 lsect->which))
6211 return true;
6212
6213 ptr_linker_section_ptr = &ptr[r_symndx];
6214
6215 if (info->shared)
6216 {
6217 /* If we are generating a shared object, we need to
6218 output a R_<xxx>_RELATIVE reloc so that the
6219 dynamic linker can adjust this GOT entry. */
6220 BFD_ASSERT (lsect->rel_section != NULL);
6221 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6222 }
6223 }
6224
6225 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6226 from internal memory. */
6227 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6228 linker_section_ptr = (elf_linker_section_pointers_t *)
6229 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6230
6231 if (!linker_section_ptr)
6232 return false;
6233
6234 linker_section_ptr->next = *ptr_linker_section_ptr;
6235 linker_section_ptr->addend = rel->r_addend;
6236 linker_section_ptr->which = lsect->which;
6237 linker_section_ptr->written_address_p = false;
6238 *ptr_linker_section_ptr = linker_section_ptr;
6239
6240 #if 0
6241 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6242 {
6243 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6244 lsect->hole_offset += ARCH_SIZE / 8;
6245 lsect->sym_offset += ARCH_SIZE / 8;
6246 if (lsect->sym_hash) /* Bump up symbol value if needed */
6247 {
6248 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6249 #ifdef DEBUG
6250 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6251 lsect->sym_hash->root.root.string,
6252 (long)ARCH_SIZE / 8,
6253 (long)lsect->sym_hash->root.u.def.value);
6254 #endif
6255 }
6256 }
6257 else
6258 #endif
6259 linker_section_ptr->offset = lsect->section->_raw_size;
6260
6261 lsect->section->_raw_size += ARCH_SIZE / 8;
6262
6263 #ifdef DEBUG
6264 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6265 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6266 #endif
6267
6268 return true;
6269 }
6270 \f
6271 #if ARCH_SIZE==64
6272 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6273 #endif
6274 #if ARCH_SIZE==32
6275 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6276 #endif
6277
6278 /* Fill in the address for a pointer generated in alinker section. */
6279
6280 bfd_vma
6281 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6282 bfd *output_bfd;
6283 bfd *input_bfd;
6284 struct bfd_link_info *info;
6285 elf_linker_section_t *lsect;
6286 struct elf_link_hash_entry *h;
6287 bfd_vma relocation;
6288 const Elf_Internal_Rela *rel;
6289 int relative_reloc;
6290 {
6291 elf_linker_section_pointers_t *linker_section_ptr;
6292
6293 BFD_ASSERT (lsect != NULL);
6294
6295 if (h != NULL) /* global symbol */
6296 {
6297 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6298 rel->r_addend,
6299 lsect->which);
6300
6301 BFD_ASSERT (linker_section_ptr != NULL);
6302
6303 if (! elf_hash_table (info)->dynamic_sections_created
6304 || (info->shared
6305 && info->symbolic
6306 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6307 {
6308 /* This is actually a static link, or it is a
6309 -Bsymbolic link and the symbol is defined
6310 locally. We must initialize this entry in the
6311 global section.
6312
6313 When doing a dynamic link, we create a .rela.<xxx>
6314 relocation entry to initialize the value. This
6315 is done in the finish_dynamic_symbol routine. */
6316 if (!linker_section_ptr->written_address_p)
6317 {
6318 linker_section_ptr->written_address_p = true;
6319 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6320 lsect->section->contents + linker_section_ptr->offset);
6321 }
6322 }
6323 }
6324 else /* local symbol */
6325 {
6326 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6327 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6328 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6329 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6330 rel->r_addend,
6331 lsect->which);
6332
6333 BFD_ASSERT (linker_section_ptr != NULL);
6334
6335 /* Write out pointer if it hasn't been rewritten out before */
6336 if (!linker_section_ptr->written_address_p)
6337 {
6338 linker_section_ptr->written_address_p = true;
6339 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6340 lsect->section->contents + linker_section_ptr->offset);
6341
6342 if (info->shared)
6343 {
6344 asection *srel = lsect->rel_section;
6345 Elf_Internal_Rela outrel;
6346
6347 /* We need to generate a relative reloc for the dynamic linker. */
6348 if (!srel)
6349 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6350 lsect->rel_name);
6351
6352 BFD_ASSERT (srel != NULL);
6353
6354 outrel.r_offset = (lsect->section->output_section->vma
6355 + lsect->section->output_offset
6356 + linker_section_ptr->offset);
6357 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6358 outrel.r_addend = 0;
6359 elf_swap_reloca_out (output_bfd, &outrel,
6360 (((Elf_External_Rela *)
6361 lsect->section->contents)
6362 + elf_section_data (lsect->section)->rel_count));
6363 ++elf_section_data (lsect->section)->rel_count;
6364 }
6365 }
6366 }
6367
6368 relocation = (lsect->section->output_offset
6369 + linker_section_ptr->offset
6370 - lsect->hole_offset
6371 - lsect->sym_offset);
6372
6373 #ifdef DEBUG
6374 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6375 lsect->name, (long)relocation, (long)relocation);
6376 #endif
6377
6378 /* Subtract out the addend, because it will get added back in by the normal
6379 processing. */
6380 return relocation - linker_section_ptr->addend;
6381 }
6382 \f
6383 /* Garbage collect unused sections. */
6384
6385 static boolean elf_gc_mark
6386 PARAMS ((struct bfd_link_info *info, asection *sec,
6387 asection * (*gc_mark_hook)
6388 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6389 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6390
6391 static boolean elf_gc_sweep
6392 PARAMS ((struct bfd_link_info *info,
6393 boolean (*gc_sweep_hook)
6394 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6395 const Elf_Internal_Rela *relocs))));
6396
6397 static boolean elf_gc_sweep_symbol
6398 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6399
6400 static boolean elf_gc_allocate_got_offsets
6401 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6402
6403 static boolean elf_gc_propagate_vtable_entries_used
6404 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6405
6406 static boolean elf_gc_smash_unused_vtentry_relocs
6407 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6408
6409 /* The mark phase of garbage collection. For a given section, mark
6410 it, and all the sections which define symbols to which it refers. */
6411
6412 static boolean
6413 elf_gc_mark (info, sec, gc_mark_hook)
6414 struct bfd_link_info *info;
6415 asection *sec;
6416 asection * (*gc_mark_hook)
6417 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6418 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6419 {
6420 boolean ret = true;
6421
6422 sec->gc_mark = 1;
6423
6424 /* Look through the section relocs. */
6425
6426 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6427 {
6428 Elf_Internal_Rela *relstart, *rel, *relend;
6429 Elf_Internal_Shdr *symtab_hdr;
6430 struct elf_link_hash_entry **sym_hashes;
6431 size_t nlocsyms;
6432 size_t extsymoff;
6433 Elf_External_Sym *locsyms, *freesyms = NULL;
6434 bfd *input_bfd = sec->owner;
6435 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6436
6437 /* GCFIXME: how to arrange so that relocs and symbols are not
6438 reread continually? */
6439
6440 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6441 sym_hashes = elf_sym_hashes (input_bfd);
6442
6443 /* Read the local symbols. */
6444 if (elf_bad_symtab (input_bfd))
6445 {
6446 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6447 extsymoff = 0;
6448 }
6449 else
6450 extsymoff = nlocsyms = symtab_hdr->sh_info;
6451 if (symtab_hdr->contents)
6452 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6453 else if (nlocsyms == 0)
6454 locsyms = NULL;
6455 else
6456 {
6457 locsyms = freesyms =
6458 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6459 if (freesyms == NULL
6460 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6461 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6462 nlocsyms, input_bfd)
6463 != nlocsyms * sizeof (Elf_External_Sym)))
6464 {
6465 ret = false;
6466 goto out1;
6467 }
6468 }
6469
6470 /* Read the relocations. */
6471 relstart = (NAME(_bfd_elf,link_read_relocs)
6472 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6473 info->keep_memory));
6474 if (relstart == NULL)
6475 {
6476 ret = false;
6477 goto out1;
6478 }
6479 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6480
6481 for (rel = relstart; rel < relend; rel++)
6482 {
6483 unsigned long r_symndx;
6484 asection *rsec;
6485 struct elf_link_hash_entry *h;
6486 Elf_Internal_Sym s;
6487
6488 r_symndx = ELF_R_SYM (rel->r_info);
6489 if (r_symndx == 0)
6490 continue;
6491
6492 if (elf_bad_symtab (sec->owner))
6493 {
6494 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6495 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6496 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6497 else
6498 {
6499 h = sym_hashes[r_symndx - extsymoff];
6500 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6501 }
6502 }
6503 else if (r_symndx >= nlocsyms)
6504 {
6505 h = sym_hashes[r_symndx - extsymoff];
6506 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6507 }
6508 else
6509 {
6510 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6511 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6512 }
6513
6514 if (rsec && !rsec->gc_mark)
6515 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6516 {
6517 ret = false;
6518 goto out2;
6519 }
6520 }
6521
6522 out2:
6523 if (!info->keep_memory)
6524 free (relstart);
6525 out1:
6526 if (freesyms)
6527 free (freesyms);
6528 }
6529
6530 return ret;
6531 }
6532
6533 /* The sweep phase of garbage collection. Remove all garbage sections. */
6534
6535 static boolean
6536 elf_gc_sweep (info, gc_sweep_hook)
6537 struct bfd_link_info *info;
6538 boolean (*gc_sweep_hook)
6539 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6540 const Elf_Internal_Rela *relocs));
6541 {
6542 bfd *sub;
6543
6544 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6545 {
6546 asection *o;
6547
6548 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6549 continue;
6550
6551 for (o = sub->sections; o != NULL; o = o->next)
6552 {
6553 /* Keep special sections. Keep .debug sections. */
6554 if ((o->flags & SEC_LINKER_CREATED)
6555 || (o->flags & SEC_DEBUGGING))
6556 o->gc_mark = 1;
6557
6558 if (o->gc_mark)
6559 continue;
6560
6561 /* Skip sweeping sections already excluded. */
6562 if (o->flags & SEC_EXCLUDE)
6563 continue;
6564
6565 /* Since this is early in the link process, it is simple
6566 to remove a section from the output. */
6567 o->flags |= SEC_EXCLUDE;
6568
6569 /* But we also have to update some of the relocation
6570 info we collected before. */
6571 if (gc_sweep_hook
6572 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6573 {
6574 Elf_Internal_Rela *internal_relocs;
6575 boolean r;
6576
6577 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6578 (o->owner, o, NULL, NULL, info->keep_memory));
6579 if (internal_relocs == NULL)
6580 return false;
6581
6582 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
6583
6584 if (!info->keep_memory)
6585 free (internal_relocs);
6586
6587 if (!r)
6588 return false;
6589 }
6590 }
6591 }
6592
6593 /* Remove the symbols that were in the swept sections from the dynamic
6594 symbol table. GCFIXME: Anyone know how to get them out of the
6595 static symbol table as well? */
6596 {
6597 int i = 0;
6598
6599 elf_link_hash_traverse (elf_hash_table (info),
6600 elf_gc_sweep_symbol,
6601 (PTR) &i);
6602
6603 elf_hash_table (info)->dynsymcount = i;
6604 }
6605
6606 return true;
6607 }
6608
6609 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6610
6611 static boolean
6612 elf_gc_sweep_symbol (h, idxptr)
6613 struct elf_link_hash_entry *h;
6614 PTR idxptr;
6615 {
6616 int *idx = (int *) idxptr;
6617
6618 if (h->dynindx != -1
6619 && ((h->root.type != bfd_link_hash_defined
6620 && h->root.type != bfd_link_hash_defweak)
6621 || h->root.u.def.section->gc_mark))
6622 h->dynindx = (*idx)++;
6623
6624 return true;
6625 }
6626
6627 /* Propogate collected vtable information. This is called through
6628 elf_link_hash_traverse. */
6629
6630 static boolean
6631 elf_gc_propagate_vtable_entries_used (h, okp)
6632 struct elf_link_hash_entry *h;
6633 PTR okp;
6634 {
6635 /* Those that are not vtables. */
6636 if (h->vtable_parent == NULL)
6637 return true;
6638
6639 /* Those vtables that do not have parents, we cannot merge. */
6640 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6641 return true;
6642
6643 /* If we've already been done, exit. */
6644 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6645 return true;
6646
6647 /* Make sure the parent's table is up to date. */
6648 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6649
6650 if (h->vtable_entries_used == NULL)
6651 {
6652 /* None of this table's entries were referenced. Re-use the
6653 parent's table. */
6654 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6655 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6656 }
6657 else
6658 {
6659 size_t n;
6660 boolean *cu, *pu;
6661
6662 /* Or the parent's entries into ours. */
6663 cu = h->vtable_entries_used;
6664 cu[-1] = true;
6665 pu = h->vtable_parent->vtable_entries_used;
6666 if (pu != NULL)
6667 {
6668 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6669 while (--n != 0)
6670 {
6671 if (*pu) *cu = true;
6672 pu++, cu++;
6673 }
6674 }
6675 }
6676
6677 return true;
6678 }
6679
6680 static boolean
6681 elf_gc_smash_unused_vtentry_relocs (h, okp)
6682 struct elf_link_hash_entry *h;
6683 PTR okp;
6684 {
6685 asection *sec;
6686 bfd_vma hstart, hend;
6687 Elf_Internal_Rela *relstart, *relend, *rel;
6688 struct elf_backend_data *bed;
6689
6690 /* Take care of both those symbols that do not describe vtables as
6691 well as those that are not loaded. */
6692 if (h->vtable_parent == NULL)
6693 return true;
6694
6695 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6696 || h->root.type == bfd_link_hash_defweak);
6697
6698 sec = h->root.u.def.section;
6699 hstart = h->root.u.def.value;
6700 hend = hstart + h->size;
6701
6702 relstart = (NAME(_bfd_elf,link_read_relocs)
6703 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6704 if (!relstart)
6705 return *(boolean *)okp = false;
6706 bed = get_elf_backend_data (sec->owner);
6707 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6708
6709 for (rel = relstart; rel < relend; ++rel)
6710 if (rel->r_offset >= hstart && rel->r_offset < hend)
6711 {
6712 /* If the entry is in use, do nothing. */
6713 if (h->vtable_entries_used
6714 && (rel->r_offset - hstart) < h->vtable_entries_size)
6715 {
6716 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6717 if (h->vtable_entries_used[entry])
6718 continue;
6719 }
6720 /* Otherwise, kill it. */
6721 rel->r_offset = rel->r_info = rel->r_addend = 0;
6722 }
6723
6724 return true;
6725 }
6726
6727 /* Do mark and sweep of unused sections. */
6728
6729 boolean
6730 elf_gc_sections (abfd, info)
6731 bfd *abfd;
6732 struct bfd_link_info *info;
6733 {
6734 boolean ok = true;
6735 bfd *sub;
6736 asection * (*gc_mark_hook)
6737 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6738 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6739
6740 if (!get_elf_backend_data (abfd)->can_gc_sections
6741 || info->relocateable || info->emitrelocations
6742 || elf_hash_table (info)->dynamic_sections_created)
6743 return true;
6744
6745 /* Apply transitive closure to the vtable entry usage info. */
6746 elf_link_hash_traverse (elf_hash_table (info),
6747 elf_gc_propagate_vtable_entries_used,
6748 (PTR) &ok);
6749 if (!ok)
6750 return false;
6751
6752 /* Kill the vtable relocations that were not used. */
6753 elf_link_hash_traverse (elf_hash_table (info),
6754 elf_gc_smash_unused_vtentry_relocs,
6755 (PTR) &ok);
6756 if (!ok)
6757 return false;
6758
6759 /* Grovel through relocs to find out who stays ... */
6760
6761 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6762 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6763 {
6764 asection *o;
6765
6766 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6767 continue;
6768
6769 for (o = sub->sections; o != NULL; o = o->next)
6770 {
6771 if (o->flags & SEC_KEEP)
6772 if (!elf_gc_mark (info, o, gc_mark_hook))
6773 return false;
6774 }
6775 }
6776
6777 /* ... and mark SEC_EXCLUDE for those that go. */
6778 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6779 return false;
6780
6781 return true;
6782 }
6783 \f
6784 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6785
6786 boolean
6787 elf_gc_record_vtinherit (abfd, sec, h, offset)
6788 bfd *abfd;
6789 asection *sec;
6790 struct elf_link_hash_entry *h;
6791 bfd_vma offset;
6792 {
6793 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6794 struct elf_link_hash_entry **search, *child;
6795 bfd_size_type extsymcount;
6796
6797 /* The sh_info field of the symtab header tells us where the
6798 external symbols start. We don't care about the local symbols at
6799 this point. */
6800 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6801 if (!elf_bad_symtab (abfd))
6802 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6803
6804 sym_hashes = elf_sym_hashes (abfd);
6805 sym_hashes_end = sym_hashes + extsymcount;
6806
6807 /* Hunt down the child symbol, which is in this section at the same
6808 offset as the relocation. */
6809 for (search = sym_hashes; search != sym_hashes_end; ++search)
6810 {
6811 if ((child = *search) != NULL
6812 && (child->root.type == bfd_link_hash_defined
6813 || child->root.type == bfd_link_hash_defweak)
6814 && child->root.u.def.section == sec
6815 && child->root.u.def.value == offset)
6816 goto win;
6817 }
6818
6819 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6820 bfd_get_filename (abfd), sec->name,
6821 (unsigned long)offset);
6822 bfd_set_error (bfd_error_invalid_operation);
6823 return false;
6824
6825 win:
6826 if (!h)
6827 {
6828 /* This *should* only be the absolute section. It could potentially
6829 be that someone has defined a non-global vtable though, which
6830 would be bad. It isn't worth paging in the local symbols to be
6831 sure though; that case should simply be handled by the assembler. */
6832
6833 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6834 }
6835 else
6836 child->vtable_parent = h;
6837
6838 return true;
6839 }
6840
6841 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6842
6843 boolean
6844 elf_gc_record_vtentry (abfd, sec, h, addend)
6845 bfd *abfd ATTRIBUTE_UNUSED;
6846 asection *sec ATTRIBUTE_UNUSED;
6847 struct elf_link_hash_entry *h;
6848 bfd_vma addend;
6849 {
6850 if (addend >= h->vtable_entries_size)
6851 {
6852 size_t size, bytes;
6853 boolean *ptr = h->vtable_entries_used;
6854
6855 /* While the symbol is undefined, we have to be prepared to handle
6856 a zero size. */
6857 if (h->root.type == bfd_link_hash_undefined)
6858 size = addend;
6859 else
6860 {
6861 size = h->size;
6862 if (size < addend)
6863 {
6864 /* Oops! We've got a reference past the defined end of
6865 the table. This is probably a bug -- shall we warn? */
6866 size = addend;
6867 }
6868 }
6869
6870 /* Allocate one extra entry for use as a "done" flag for the
6871 consolidation pass. */
6872 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6873
6874 if (ptr)
6875 {
6876 ptr = bfd_realloc (ptr - 1, bytes);
6877
6878 if (ptr != NULL)
6879 {
6880 size_t oldbytes;
6881
6882 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6883 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6884 }
6885 }
6886 else
6887 ptr = bfd_zmalloc (bytes);
6888
6889 if (ptr == NULL)
6890 return false;
6891
6892 /* And arrange for that done flag to be at index -1. */
6893 h->vtable_entries_used = ptr + 1;
6894 h->vtable_entries_size = size;
6895 }
6896
6897 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6898
6899 return true;
6900 }
6901
6902 /* And an accompanying bit to work out final got entry offsets once
6903 we're done. Should be called from final_link. */
6904
6905 boolean
6906 elf_gc_common_finalize_got_offsets (abfd, info)
6907 bfd *abfd;
6908 struct bfd_link_info *info;
6909 {
6910 bfd *i;
6911 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6912 bfd_vma gotoff;
6913
6914 /* The GOT offset is relative to the .got section, but the GOT header is
6915 put into the .got.plt section, if the backend uses it. */
6916 if (bed->want_got_plt)
6917 gotoff = 0;
6918 else
6919 gotoff = bed->got_header_size;
6920
6921 /* Do the local .got entries first. */
6922 for (i = info->input_bfds; i; i = i->link_next)
6923 {
6924 bfd_signed_vma *local_got;
6925 bfd_size_type j, locsymcount;
6926 Elf_Internal_Shdr *symtab_hdr;
6927
6928 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6929 continue;
6930
6931 local_got = elf_local_got_refcounts (i);
6932 if (!local_got)
6933 continue;
6934
6935 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6936 if (elf_bad_symtab (i))
6937 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6938 else
6939 locsymcount = symtab_hdr->sh_info;
6940
6941 for (j = 0; j < locsymcount; ++j)
6942 {
6943 if (local_got[j] > 0)
6944 {
6945 local_got[j] = gotoff;
6946 gotoff += ARCH_SIZE / 8;
6947 }
6948 else
6949 local_got[j] = (bfd_vma) -1;
6950 }
6951 }
6952
6953 /* Then the global .got entries. .plt refcounts are handled by
6954 adjust_dynamic_symbol */
6955 elf_link_hash_traverse (elf_hash_table (info),
6956 elf_gc_allocate_got_offsets,
6957 (PTR) &gotoff);
6958 return true;
6959 }
6960
6961 /* We need a special top-level link routine to convert got reference counts
6962 to real got offsets. */
6963
6964 static boolean
6965 elf_gc_allocate_got_offsets (h, offarg)
6966 struct elf_link_hash_entry *h;
6967 PTR offarg;
6968 {
6969 bfd_vma *off = (bfd_vma *) offarg;
6970
6971 if (h->got.refcount > 0)
6972 {
6973 h->got.offset = off[0];
6974 off[0] += ARCH_SIZE / 8;
6975 }
6976 else
6977 h->got.offset = (bfd_vma) -1;
6978
6979 return true;
6980 }
6981
6982 /* Many folk need no more in the way of final link than this, once
6983 got entry reference counting is enabled. */
6984
6985 boolean
6986 elf_gc_common_final_link (abfd, info)
6987 bfd *abfd;
6988 struct bfd_link_info *info;
6989 {
6990 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6991 return false;
6992
6993 /* Invoke the regular ELF backend linker to do all the work. */
6994 return elf_bfd_final_link (abfd, info);
6995 }
6996
6997 /* This function will be called though elf_link_hash_traverse to store
6998 all hash value of the exported symbols in an array. */
6999
7000 static boolean
7001 elf_collect_hash_codes (h, data)
7002 struct elf_link_hash_entry *h;
7003 PTR data;
7004 {
7005 unsigned long **valuep = (unsigned long **) data;
7006 const char *name;
7007 char *p;
7008 unsigned long ha;
7009 char *alc = NULL;
7010
7011 /* Ignore indirect symbols. These are added by the versioning code. */
7012 if (h->dynindx == -1)
7013 return true;
7014
7015 name = h->root.root.string;
7016 p = strchr (name, ELF_VER_CHR);
7017 if (p != NULL)
7018 {
7019 alc = bfd_malloc (p - name + 1);
7020 memcpy (alc, name, p - name);
7021 alc[p - name] = '\0';
7022 name = alc;
7023 }
7024
7025 /* Compute the hash value. */
7026 ha = bfd_elf_hash (name);
7027
7028 /* Store the found hash value in the array given as the argument. */
7029 *(*valuep)++ = ha;
7030
7031 /* And store it in the struct so that we can put it in the hash table
7032 later. */
7033 h->elf_hash_value = ha;
7034
7035 if (alc != NULL)
7036 free (alc);
7037
7038 return true;
7039 }
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