2000-04-27 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 bfd_byte *dynver = NULL;
899 Elf_External_Versym *extversym = NULL;
900 Elf_External_Versym *ever;
901 Elf_External_Dyn *dynbuf = NULL;
902 struct elf_link_hash_entry *weaks;
903 Elf_External_Sym *esym;
904 Elf_External_Sym *esymend;
905 struct elf_backend_data *bed;
906 boolean dt_needed;
907
908 bed = get_elf_backend_data (abfd);
909 add_symbol_hook = bed->elf_add_symbol_hook;
910 collect = bed->collect;
911
912 if ((abfd->flags & DYNAMIC) == 0)
913 dynamic = false;
914 else
915 {
916 dynamic = true;
917
918 /* You can't use -r against a dynamic object. Also, there's no
919 hope of using a dynamic object which does not exactly match
920 the format of the output file. */
921 if (info->relocateable || info->hash->creator != abfd->xvec)
922 {
923 bfd_set_error (bfd_error_invalid_operation);
924 goto error_return;
925 }
926 }
927
928 /* As a GNU extension, any input sections which are named
929 .gnu.warning.SYMBOL are treated as warning symbols for the given
930 symbol. This differs from .gnu.warning sections, which generate
931 warnings when they are included in an output file. */
932 if (! info->shared)
933 {
934 asection *s;
935
936 for (s = abfd->sections; s != NULL; s = s->next)
937 {
938 const char *name;
939
940 name = bfd_get_section_name (abfd, s);
941 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
942 {
943 char *msg;
944 bfd_size_type sz;
945
946 name += sizeof ".gnu.warning." - 1;
947
948 /* If this is a shared object, then look up the symbol
949 in the hash table. If it is there, and it is already
950 been defined, then we will not be using the entry
951 from this shared object, so we don't need to warn.
952 FIXME: If we see the definition in a regular object
953 later on, we will warn, but we shouldn't. The only
954 fix is to keep track of what warnings we are supposed
955 to emit, and then handle them all at the end of the
956 link. */
957 if (dynamic && abfd->xvec == info->hash->creator)
958 {
959 struct elf_link_hash_entry *h;
960
961 h = elf_link_hash_lookup (elf_hash_table (info), name,
962 false, false, true);
963
964 /* FIXME: What about bfd_link_hash_common? */
965 if (h != NULL
966 && (h->root.type == bfd_link_hash_defined
967 || h->root.type == bfd_link_hash_defweak))
968 {
969 /* We don't want to issue this warning. Clobber
970 the section size so that the warning does not
971 get copied into the output file. */
972 s->_raw_size = 0;
973 continue;
974 }
975 }
976
977 sz = bfd_section_size (abfd, s);
978 msg = (char *) bfd_alloc (abfd, sz + 1);
979 if (msg == NULL)
980 goto error_return;
981
982 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
983 goto error_return;
984
985 msg[sz] = '\0';
986
987 if (! (_bfd_generic_link_add_one_symbol
988 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
989 false, collect, (struct bfd_link_hash_entry **) NULL)))
990 goto error_return;
991
992 if (! info->relocateable)
993 {
994 /* Clobber the section size so that the warning does
995 not get copied into the output file. */
996 s->_raw_size = 0;
997 }
998 }
999 }
1000 }
1001
1002 /* If this is a dynamic object, we always link against the .dynsym
1003 symbol table, not the .symtab symbol table. The dynamic linker
1004 will only see the .dynsym symbol table, so there is no reason to
1005 look at .symtab for a dynamic object. */
1006
1007 if (! dynamic || elf_dynsymtab (abfd) == 0)
1008 hdr = &elf_tdata (abfd)->symtab_hdr;
1009 else
1010 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1011
1012 if (dynamic)
1013 {
1014 /* Read in any version definitions. */
1015
1016 if (! _bfd_elf_slurp_version_tables (abfd))
1017 goto error_return;
1018
1019 /* Read in the symbol versions, but don't bother to convert them
1020 to internal format. */
1021 if (elf_dynversym (abfd) != 0)
1022 {
1023 Elf_Internal_Shdr *versymhdr;
1024
1025 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1026 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1027 if (extversym == NULL)
1028 goto error_return;
1029 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1030 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1031 != versymhdr->sh_size))
1032 goto error_return;
1033 }
1034 }
1035
1036 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1037
1038 /* The sh_info field of the symtab header tells us where the
1039 external symbols start. We don't care about the local symbols at
1040 this point. */
1041 if (elf_bad_symtab (abfd))
1042 {
1043 extsymcount = symcount;
1044 extsymoff = 0;
1045 }
1046 else
1047 {
1048 extsymcount = symcount - hdr->sh_info;
1049 extsymoff = hdr->sh_info;
1050 }
1051
1052 buf = ((Elf_External_Sym *)
1053 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1054 if (buf == NULL && extsymcount != 0)
1055 goto error_return;
1056
1057 /* We store a pointer to the hash table entry for each external
1058 symbol. */
1059 sym_hash = ((struct elf_link_hash_entry **)
1060 bfd_alloc (abfd,
1061 extsymcount * sizeof (struct elf_link_hash_entry *)));
1062 if (sym_hash == NULL)
1063 goto error_return;
1064 elf_sym_hashes (abfd) = sym_hash;
1065
1066 dt_needed = false;
1067
1068 if (! dynamic)
1069 {
1070 /* If we are creating a shared library, create all the dynamic
1071 sections immediately. We need to attach them to something,
1072 so we attach them to this BFD, provided it is the right
1073 format. FIXME: If there are no input BFD's of the same
1074 format as the output, we can't make a shared library. */
1075 if (info->shared
1076 && ! elf_hash_table (info)->dynamic_sections_created
1077 && abfd->xvec == info->hash->creator)
1078 {
1079 if (! elf_link_create_dynamic_sections (abfd, info))
1080 goto error_return;
1081 }
1082 }
1083 else
1084 {
1085 asection *s;
1086 boolean add_needed;
1087 const char *name;
1088 bfd_size_type oldsize;
1089 bfd_size_type strindex;
1090
1091 /* Find the name to use in a DT_NEEDED entry that refers to this
1092 object. If the object has a DT_SONAME entry, we use it.
1093 Otherwise, if the generic linker stuck something in
1094 elf_dt_name, we use that. Otherwise, we just use the file
1095 name. If the generic linker put a null string into
1096 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1097 there is a DT_SONAME entry. */
1098 add_needed = true;
1099 name = bfd_get_filename (abfd);
1100 if (elf_dt_name (abfd) != NULL)
1101 {
1102 name = elf_dt_name (abfd);
1103 if (*name == '\0')
1104 {
1105 if (elf_dt_soname (abfd) != NULL)
1106 dt_needed = true;
1107
1108 add_needed = false;
1109 }
1110 }
1111 s = bfd_get_section_by_name (abfd, ".dynamic");
1112 if (s != NULL)
1113 {
1114 Elf_External_Dyn *extdyn;
1115 Elf_External_Dyn *extdynend;
1116 int elfsec;
1117 unsigned long link;
1118 int rpath;
1119 int runpath;
1120
1121 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1122 if (dynbuf == NULL)
1123 goto error_return;
1124
1125 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1126 (file_ptr) 0, s->_raw_size))
1127 goto error_return;
1128
1129 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1130 if (elfsec == -1)
1131 goto error_return;
1132 link = elf_elfsections (abfd)[elfsec]->sh_link;
1133
1134 {
1135 /* The shared libraries distributed with hpux11 have a bogus
1136 sh_link field for the ".dynamic" section. This code detects
1137 when LINK refers to a section that is not a string table and
1138 tries to find the string table for the ".dynsym" section
1139 instead. */
1140 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1141 if (hdr->sh_type != SHT_STRTAB)
1142 {
1143 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1144 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1145 if (elfsec == -1)
1146 goto error_return;
1147 link = elf_elfsections (abfd)[elfsec]->sh_link;
1148 }
1149 }
1150
1151 extdyn = dynbuf;
1152 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1153 rpath = 0;
1154 runpath = 0;
1155 for (; extdyn < extdynend; extdyn++)
1156 {
1157 Elf_Internal_Dyn dyn;
1158
1159 elf_swap_dyn_in (abfd, extdyn, &dyn);
1160 if (dyn.d_tag == DT_SONAME)
1161 {
1162 name = bfd_elf_string_from_elf_section (abfd, link,
1163 dyn.d_un.d_val);
1164 if (name == NULL)
1165 goto error_return;
1166 }
1167 if (dyn.d_tag == DT_NEEDED)
1168 {
1169 struct bfd_link_needed_list *n, **pn;
1170 char *fnm, *anm;
1171
1172 n = ((struct bfd_link_needed_list *)
1173 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1174 fnm = bfd_elf_string_from_elf_section (abfd, link,
1175 dyn.d_un.d_val);
1176 if (n == NULL || fnm == NULL)
1177 goto error_return;
1178 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1179 if (anm == NULL)
1180 goto error_return;
1181 strcpy (anm, fnm);
1182 n->name = anm;
1183 n->by = abfd;
1184 n->next = NULL;
1185 for (pn = &elf_hash_table (info)->needed;
1186 *pn != NULL;
1187 pn = &(*pn)->next)
1188 ;
1189 *pn = n;
1190 }
1191 if (dyn.d_tag == DT_RUNPATH)
1192 {
1193 struct bfd_link_needed_list *n, **pn;
1194 char *fnm, *anm;
1195
1196 /* When we see DT_RPATH before DT_RUNPATH, we have
1197 to clear runpath. Do _NOT_ bfd_release, as that
1198 frees all more recently bfd_alloc'd blocks as
1199 well. */
1200 if (rpath && elf_hash_table (info)->runpath)
1201 elf_hash_table (info)->runpath = NULL;
1202
1203 n = ((struct bfd_link_needed_list *)
1204 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1205 fnm = bfd_elf_string_from_elf_section (abfd, link,
1206 dyn.d_un.d_val);
1207 if (n == NULL || fnm == NULL)
1208 goto error_return;
1209 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1210 if (anm == NULL)
1211 goto error_return;
1212 strcpy (anm, fnm);
1213 n->name = anm;
1214 n->by = abfd;
1215 n->next = NULL;
1216 for (pn = &elf_hash_table (info)->runpath;
1217 *pn != NULL;
1218 pn = &(*pn)->next)
1219 ;
1220 *pn = n;
1221 runpath = 1;
1222 rpath = 0;
1223 }
1224 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
1225 if (!runpath && dyn.d_tag == DT_RPATH)
1226 {
1227 struct bfd_link_needed_list *n, **pn;
1228 char *fnm, *anm;
1229
1230 n = ((struct bfd_link_needed_list *)
1231 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1232 fnm = bfd_elf_string_from_elf_section (abfd, link,
1233 dyn.d_un.d_val);
1234 if (n == NULL || fnm == NULL)
1235 goto error_return;
1236 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1237 if (anm == NULL)
1238 goto error_return;
1239 strcpy (anm, fnm);
1240 n->name = anm;
1241 n->by = abfd;
1242 n->next = NULL;
1243 for (pn = &elf_hash_table (info)->runpath;
1244 *pn != NULL;
1245 pn = &(*pn)->next)
1246 ;
1247 *pn = n;
1248 rpath = 1;
1249 }
1250 }
1251
1252 free (dynbuf);
1253 dynbuf = NULL;
1254 }
1255
1256 /* We do not want to include any of the sections in a dynamic
1257 object in the output file. We hack by simply clobbering the
1258 list of sections in the BFD. This could be handled more
1259 cleanly by, say, a new section flag; the existing
1260 SEC_NEVER_LOAD flag is not the one we want, because that one
1261 still implies that the section takes up space in the output
1262 file. */
1263 abfd->sections = NULL;
1264 abfd->section_count = 0;
1265
1266 /* If this is the first dynamic object found in the link, create
1267 the special sections required for dynamic linking. */
1268 if (! elf_hash_table (info)->dynamic_sections_created)
1269 {
1270 if (! elf_link_create_dynamic_sections (abfd, info))
1271 goto error_return;
1272 }
1273
1274 if (add_needed)
1275 {
1276 /* Add a DT_NEEDED entry for this dynamic object. */
1277 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1278 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1279 true, false);
1280 if (strindex == (bfd_size_type) -1)
1281 goto error_return;
1282
1283 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1284 {
1285 asection *sdyn;
1286 Elf_External_Dyn *dyncon, *dynconend;
1287
1288 /* The hash table size did not change, which means that
1289 the dynamic object name was already entered. If we
1290 have already included this dynamic object in the
1291 link, just ignore it. There is no reason to include
1292 a particular dynamic object more than once. */
1293 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1294 ".dynamic");
1295 BFD_ASSERT (sdyn != NULL);
1296
1297 dyncon = (Elf_External_Dyn *) sdyn->contents;
1298 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1299 sdyn->_raw_size);
1300 for (; dyncon < dynconend; dyncon++)
1301 {
1302 Elf_Internal_Dyn dyn;
1303
1304 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1305 &dyn);
1306 if (dyn.d_tag == DT_NEEDED
1307 && dyn.d_un.d_val == strindex)
1308 {
1309 if (buf != NULL)
1310 free (buf);
1311 if (extversym != NULL)
1312 free (extversym);
1313 return true;
1314 }
1315 }
1316 }
1317
1318 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1319 goto error_return;
1320 }
1321
1322 /* Save the SONAME, if there is one, because sometimes the
1323 linker emulation code will need to know it. */
1324 if (*name == '\0')
1325 name = bfd_get_filename (abfd);
1326 elf_dt_name (abfd) = name;
1327 }
1328
1329 if (bfd_seek (abfd,
1330 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1331 SEEK_SET) != 0
1332 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1333 != extsymcount * sizeof (Elf_External_Sym)))
1334 goto error_return;
1335
1336 weaks = NULL;
1337
1338 ever = extversym != NULL ? extversym + extsymoff : NULL;
1339 esymend = buf + extsymcount;
1340 for (esym = buf;
1341 esym < esymend;
1342 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1343 {
1344 Elf_Internal_Sym sym;
1345 int bind;
1346 bfd_vma value;
1347 asection *sec;
1348 flagword flags;
1349 const char *name;
1350 struct elf_link_hash_entry *h;
1351 boolean definition;
1352 boolean size_change_ok, type_change_ok;
1353 boolean new_weakdef;
1354 unsigned int old_alignment;
1355
1356 elf_swap_symbol_in (abfd, esym, &sym);
1357
1358 flags = BSF_NO_FLAGS;
1359 sec = NULL;
1360 value = sym.st_value;
1361 *sym_hash = NULL;
1362
1363 bind = ELF_ST_BIND (sym.st_info);
1364 if (bind == STB_LOCAL)
1365 {
1366 /* This should be impossible, since ELF requires that all
1367 global symbols follow all local symbols, and that sh_info
1368 point to the first global symbol. Unfortunatealy, Irix 5
1369 screws this up. */
1370 continue;
1371 }
1372 else if (bind == STB_GLOBAL)
1373 {
1374 if (sym.st_shndx != SHN_UNDEF
1375 && sym.st_shndx != SHN_COMMON)
1376 flags = BSF_GLOBAL;
1377 }
1378 else if (bind == STB_WEAK)
1379 flags = BSF_WEAK;
1380 else
1381 {
1382 /* Leave it up to the processor backend. */
1383 }
1384
1385 if (sym.st_shndx == SHN_UNDEF)
1386 sec = bfd_und_section_ptr;
1387 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1388 {
1389 sec = section_from_elf_index (abfd, sym.st_shndx);
1390 if (sec == NULL)
1391 sec = bfd_abs_section_ptr;
1392 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1393 value -= sec->vma;
1394 }
1395 else if (sym.st_shndx == SHN_ABS)
1396 sec = bfd_abs_section_ptr;
1397 else if (sym.st_shndx == SHN_COMMON)
1398 {
1399 sec = bfd_com_section_ptr;
1400 /* What ELF calls the size we call the value. What ELF
1401 calls the value we call the alignment. */
1402 value = sym.st_size;
1403 }
1404 else
1405 {
1406 /* Leave it up to the processor backend. */
1407 }
1408
1409 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1410 if (name == (const char *) NULL)
1411 goto error_return;
1412
1413 if (add_symbol_hook)
1414 {
1415 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1416 &value))
1417 goto error_return;
1418
1419 /* The hook function sets the name to NULL if this symbol
1420 should be skipped for some reason. */
1421 if (name == (const char *) NULL)
1422 continue;
1423 }
1424
1425 /* Sanity check that all possibilities were handled. */
1426 if (sec == (asection *) NULL)
1427 {
1428 bfd_set_error (bfd_error_bad_value);
1429 goto error_return;
1430 }
1431
1432 if (bfd_is_und_section (sec)
1433 || bfd_is_com_section (sec))
1434 definition = false;
1435 else
1436 definition = true;
1437
1438 size_change_ok = false;
1439 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1440 old_alignment = 0;
1441 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1442 {
1443 Elf_Internal_Versym iver;
1444 unsigned int vernum = 0;
1445 boolean override;
1446
1447 if (ever != NULL)
1448 {
1449 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1450 vernum = iver.vs_vers & VERSYM_VERSION;
1451
1452 /* If this is a hidden symbol, or if it is not version
1453 1, we append the version name to the symbol name.
1454 However, we do not modify a non-hidden absolute
1455 symbol, because it might be the version symbol
1456 itself. FIXME: What if it isn't? */
1457 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1458 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1459 {
1460 const char *verstr;
1461 int namelen, newlen;
1462 char *newname, *p;
1463
1464 if (sym.st_shndx != SHN_UNDEF)
1465 {
1466 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1467 {
1468 (*_bfd_error_handler)
1469 (_("%s: %s: invalid version %u (max %d)"),
1470 bfd_get_filename (abfd), name, vernum,
1471 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1472 bfd_set_error (bfd_error_bad_value);
1473 goto error_return;
1474 }
1475 else if (vernum > 1)
1476 verstr =
1477 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1478 else
1479 verstr = "";
1480 }
1481 else
1482 {
1483 /* We cannot simply test for the number of
1484 entries in the VERNEED section since the
1485 numbers for the needed versions do not start
1486 at 0. */
1487 Elf_Internal_Verneed *t;
1488
1489 verstr = NULL;
1490 for (t = elf_tdata (abfd)->verref;
1491 t != NULL;
1492 t = t->vn_nextref)
1493 {
1494 Elf_Internal_Vernaux *a;
1495
1496 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1497 {
1498 if (a->vna_other == vernum)
1499 {
1500 verstr = a->vna_nodename;
1501 break;
1502 }
1503 }
1504 if (a != NULL)
1505 break;
1506 }
1507 if (verstr == NULL)
1508 {
1509 (*_bfd_error_handler)
1510 (_("%s: %s: invalid needed version %d"),
1511 bfd_get_filename (abfd), name, vernum);
1512 bfd_set_error (bfd_error_bad_value);
1513 goto error_return;
1514 }
1515 }
1516
1517 namelen = strlen (name);
1518 newlen = namelen + strlen (verstr) + 2;
1519 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1520 ++newlen;
1521
1522 newname = (char *) bfd_alloc (abfd, newlen);
1523 if (newname == NULL)
1524 goto error_return;
1525 strcpy (newname, name);
1526 p = newname + namelen;
1527 *p++ = ELF_VER_CHR;
1528 /* If this is a defined non-hidden version symbol,
1529 we add another @ to the name. This indicates the
1530 default version of the symbol. */
1531 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1532 && sym.st_shndx != SHN_UNDEF)
1533 *p++ = ELF_VER_CHR;
1534 strcpy (p, verstr);
1535
1536 name = newname;
1537 }
1538 }
1539
1540 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1541 sym_hash, &override, &type_change_ok,
1542 &size_change_ok, dt_needed))
1543 goto error_return;
1544
1545 if (override)
1546 definition = false;
1547
1548 h = *sym_hash;
1549 while (h->root.type == bfd_link_hash_indirect
1550 || h->root.type == bfd_link_hash_warning)
1551 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1552
1553 /* Remember the old alignment if this is a common symbol, so
1554 that we don't reduce the alignment later on. We can't
1555 check later, because _bfd_generic_link_add_one_symbol
1556 will set a default for the alignment which we want to
1557 override. */
1558 if (h->root.type == bfd_link_hash_common)
1559 old_alignment = h->root.u.c.p->alignment_power;
1560
1561 if (elf_tdata (abfd)->verdef != NULL
1562 && ! override
1563 && vernum > 1
1564 && definition)
1565 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1566 }
1567
1568 if (! (_bfd_generic_link_add_one_symbol
1569 (info, abfd, name, flags, sec, value, (const char *) NULL,
1570 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1571 goto error_return;
1572
1573 h = *sym_hash;
1574 while (h->root.type == bfd_link_hash_indirect
1575 || h->root.type == bfd_link_hash_warning)
1576 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1577 *sym_hash = h;
1578
1579 new_weakdef = false;
1580 if (dynamic
1581 && definition
1582 && (flags & BSF_WEAK) != 0
1583 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1584 && info->hash->creator->flavour == bfd_target_elf_flavour
1585 && h->weakdef == NULL)
1586 {
1587 /* Keep a list of all weak defined non function symbols from
1588 a dynamic object, using the weakdef field. Later in this
1589 function we will set the weakdef field to the correct
1590 value. We only put non-function symbols from dynamic
1591 objects on this list, because that happens to be the only
1592 time we need to know the normal symbol corresponding to a
1593 weak symbol, and the information is time consuming to
1594 figure out. If the weakdef field is not already NULL,
1595 then this symbol was already defined by some previous
1596 dynamic object, and we will be using that previous
1597 definition anyhow. */
1598
1599 h->weakdef = weaks;
1600 weaks = h;
1601 new_weakdef = true;
1602 }
1603
1604 /* Set the alignment of a common symbol. */
1605 if (sym.st_shndx == SHN_COMMON
1606 && h->root.type == bfd_link_hash_common)
1607 {
1608 unsigned int align;
1609
1610 align = bfd_log2 (sym.st_value);
1611 if (align > old_alignment
1612 /* Permit an alignment power of zero if an alignment of one
1613 is specified and no other alignments have been specified. */
1614 || (sym.st_value == 1 && old_alignment == 0))
1615 h->root.u.c.p->alignment_power = align;
1616 }
1617
1618 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1619 {
1620 int old_flags;
1621 boolean dynsym;
1622 int new_flag;
1623
1624 /* Remember the symbol size and type. */
1625 if (sym.st_size != 0
1626 && (definition || h->size == 0))
1627 {
1628 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1629 (*_bfd_error_handler)
1630 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1631 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1632 bfd_get_filename (abfd));
1633
1634 h->size = sym.st_size;
1635 }
1636
1637 /* If this is a common symbol, then we always want H->SIZE
1638 to be the size of the common symbol. The code just above
1639 won't fix the size if a common symbol becomes larger. We
1640 don't warn about a size change here, because that is
1641 covered by --warn-common. */
1642 if (h->root.type == bfd_link_hash_common)
1643 h->size = h->root.u.c.size;
1644
1645 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1646 && (definition || h->type == STT_NOTYPE))
1647 {
1648 if (h->type != STT_NOTYPE
1649 && h->type != ELF_ST_TYPE (sym.st_info)
1650 && ! type_change_ok)
1651 (*_bfd_error_handler)
1652 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1653 name, h->type, ELF_ST_TYPE (sym.st_info),
1654 bfd_get_filename (abfd));
1655
1656 h->type = ELF_ST_TYPE (sym.st_info);
1657 }
1658
1659 /* If st_other has a processor-specific meaning, specific code
1660 might be needed here. */
1661 if (sym.st_other != 0)
1662 {
1663 /* Combine visibilities, using the most constraining one. */
1664 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1665 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1666
1667 if (symvis && (hvis > symvis || hvis == 0))
1668 h->other = sym.st_other;
1669
1670 /* If neither has visibility, use the st_other of the
1671 definition. This is an arbitrary choice, since the
1672 other bits have no general meaning. */
1673 if (!symvis && !hvis
1674 && (definition || h->other == 0))
1675 h->other = sym.st_other;
1676 }
1677
1678 /* Set a flag in the hash table entry indicating the type of
1679 reference or definition we just found. Keep a count of
1680 the number of dynamic symbols we find. A dynamic symbol
1681 is one which is referenced or defined by both a regular
1682 object and a shared object. */
1683 old_flags = h->elf_link_hash_flags;
1684 dynsym = false;
1685 if (! dynamic)
1686 {
1687 if (! definition)
1688 {
1689 new_flag = ELF_LINK_HASH_REF_REGULAR;
1690 if (bind != STB_WEAK)
1691 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1692 }
1693 else
1694 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1695 if (info->shared
1696 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1697 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1698 dynsym = true;
1699 }
1700 else
1701 {
1702 if (! definition)
1703 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1704 else
1705 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1706 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1707 | ELF_LINK_HASH_REF_REGULAR)) != 0
1708 || (h->weakdef != NULL
1709 && ! new_weakdef
1710 && h->weakdef->dynindx != -1))
1711 dynsym = true;
1712 }
1713
1714 h->elf_link_hash_flags |= new_flag;
1715
1716 /* If this symbol has a version, and it is the default
1717 version, we create an indirect symbol from the default
1718 name to the fully decorated name. This will cause
1719 external references which do not specify a version to be
1720 bound to this version of the symbol. */
1721 if (definition || h->root.type == bfd_link_hash_common)
1722 {
1723 char *p;
1724
1725 p = strchr (name, ELF_VER_CHR);
1726 if (p != NULL && p[1] == ELF_VER_CHR)
1727 {
1728 char *shortname;
1729 struct elf_link_hash_entry *hi;
1730 boolean override;
1731
1732 shortname = bfd_hash_allocate (&info->hash->table,
1733 p - name + 1);
1734 if (shortname == NULL)
1735 goto error_return;
1736 strncpy (shortname, name, p - name);
1737 shortname[p - name] = '\0';
1738
1739 /* We are going to create a new symbol. Merge it
1740 with any existing symbol with this name. For the
1741 purposes of the merge, act as though we were
1742 defining the symbol we just defined, although we
1743 actually going to define an indirect symbol. */
1744 type_change_ok = false;
1745 size_change_ok = false;
1746 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1747 &value, &hi, &override,
1748 &type_change_ok,
1749 &size_change_ok, dt_needed))
1750 goto error_return;
1751
1752 if (! override)
1753 {
1754 if (! (_bfd_generic_link_add_one_symbol
1755 (info, abfd, shortname, BSF_INDIRECT,
1756 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1757 collect, (struct bfd_link_hash_entry **) &hi)))
1758 goto error_return;
1759 }
1760 else
1761 {
1762 /* In this case the symbol named SHORTNAME is
1763 overriding the indirect symbol we want to
1764 add. We were planning on making SHORTNAME an
1765 indirect symbol referring to NAME. SHORTNAME
1766 is the name without a version. NAME is the
1767 fully versioned name, and it is the default
1768 version.
1769
1770 Overriding means that we already saw a
1771 definition for the symbol SHORTNAME in a
1772 regular object, and it is overriding the
1773 symbol defined in the dynamic object.
1774
1775 When this happens, we actually want to change
1776 NAME, the symbol we just added, to refer to
1777 SHORTNAME. This will cause references to
1778 NAME in the shared object to become
1779 references to SHORTNAME in the regular
1780 object. This is what we expect when we
1781 override a function in a shared object: that
1782 the references in the shared object will be
1783 mapped to the definition in the regular
1784 object. */
1785
1786 while (hi->root.type == bfd_link_hash_indirect
1787 || hi->root.type == bfd_link_hash_warning)
1788 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1789
1790 h->root.type = bfd_link_hash_indirect;
1791 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1792 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1793 {
1794 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1795 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1796 if (hi->elf_link_hash_flags
1797 & (ELF_LINK_HASH_REF_REGULAR
1798 | ELF_LINK_HASH_DEF_REGULAR))
1799 {
1800 if (! _bfd_elf_link_record_dynamic_symbol (info,
1801 hi))
1802 goto error_return;
1803 }
1804 }
1805
1806 /* Now set HI to H, so that the following code
1807 will set the other fields correctly. */
1808 hi = h;
1809 }
1810
1811 /* If there is a duplicate definition somewhere,
1812 then HI may not point to an indirect symbol. We
1813 will have reported an error to the user in that
1814 case. */
1815
1816 if (hi->root.type == bfd_link_hash_indirect)
1817 {
1818 struct elf_link_hash_entry *ht;
1819
1820 /* If the symbol became indirect, then we assume
1821 that we have not seen a definition before. */
1822 BFD_ASSERT ((hi->elf_link_hash_flags
1823 & (ELF_LINK_HASH_DEF_DYNAMIC
1824 | ELF_LINK_HASH_DEF_REGULAR))
1825 == 0);
1826
1827 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1828 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1829
1830 /* See if the new flags lead us to realize that
1831 the symbol must be dynamic. */
1832 if (! dynsym)
1833 {
1834 if (! dynamic)
1835 {
1836 if (info->shared
1837 || ((hi->elf_link_hash_flags
1838 & ELF_LINK_HASH_REF_DYNAMIC)
1839 != 0))
1840 dynsym = true;
1841 }
1842 else
1843 {
1844 if ((hi->elf_link_hash_flags
1845 & ELF_LINK_HASH_REF_REGULAR) != 0)
1846 dynsym = true;
1847 }
1848 }
1849 }
1850
1851 /* We also need to define an indirection from the
1852 nondefault version of the symbol. */
1853
1854 shortname = bfd_hash_allocate (&info->hash->table,
1855 strlen (name));
1856 if (shortname == NULL)
1857 goto error_return;
1858 strncpy (shortname, name, p - name);
1859 strcpy (shortname + (p - name), p + 1);
1860
1861 /* Once again, merge with any existing symbol. */
1862 type_change_ok = false;
1863 size_change_ok = false;
1864 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1865 &value, &hi, &override,
1866 &type_change_ok,
1867 &size_change_ok, dt_needed))
1868 goto error_return;
1869
1870 if (override)
1871 {
1872 /* Here SHORTNAME is a versioned name, so we
1873 don't expect to see the type of override we
1874 do in the case above. */
1875 (*_bfd_error_handler)
1876 (_("%s: warning: unexpected redefinition of `%s'"),
1877 bfd_get_filename (abfd), shortname);
1878 }
1879 else
1880 {
1881 if (! (_bfd_generic_link_add_one_symbol
1882 (info, abfd, shortname, BSF_INDIRECT,
1883 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1884 collect, (struct bfd_link_hash_entry **) &hi)))
1885 goto error_return;
1886
1887 /* If there is a duplicate definition somewhere,
1888 then HI may not point to an indirect symbol.
1889 We will have reported an error to the user in
1890 that case. */
1891
1892 if (hi->root.type == bfd_link_hash_indirect)
1893 {
1894 /* If the symbol became indirect, then we
1895 assume that we have not seen a definition
1896 before. */
1897 BFD_ASSERT ((hi->elf_link_hash_flags
1898 & (ELF_LINK_HASH_DEF_DYNAMIC
1899 | ELF_LINK_HASH_DEF_REGULAR))
1900 == 0);
1901
1902 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1903
1904 /* See if the new flags lead us to realize
1905 that the symbol must be dynamic. */
1906 if (! dynsym)
1907 {
1908 if (! dynamic)
1909 {
1910 if (info->shared
1911 || ((hi->elf_link_hash_flags
1912 & ELF_LINK_HASH_REF_DYNAMIC)
1913 != 0))
1914 dynsym = true;
1915 }
1916 else
1917 {
1918 if ((hi->elf_link_hash_flags
1919 & ELF_LINK_HASH_REF_REGULAR) != 0)
1920 dynsym = true;
1921 }
1922 }
1923 }
1924 }
1925 }
1926 }
1927
1928 if (dynsym && h->dynindx == -1)
1929 {
1930 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1931 goto error_return;
1932 if (h->weakdef != NULL
1933 && ! new_weakdef
1934 && h->weakdef->dynindx == -1)
1935 {
1936 if (! _bfd_elf_link_record_dynamic_symbol (info,
1937 h->weakdef))
1938 goto error_return;
1939 }
1940 }
1941 else if (dynsym && h->dynindx != -1)
1942 /* If the symbol already has a dynamic index, but
1943 visibility says it should not be visible, turn it into
1944 a local symbol. */
1945 switch (ELF_ST_VISIBILITY (h->other))
1946 {
1947 case STV_INTERNAL:
1948 case STV_HIDDEN:
1949 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1950 (*bed->elf_backend_hide_symbol) (info, h);
1951 break;
1952 }
1953
1954 if (dt_needed && definition
1955 && (h->elf_link_hash_flags
1956 & ELF_LINK_HASH_REF_REGULAR) != 0)
1957 {
1958 bfd_size_type oldsize;
1959 bfd_size_type strindex;
1960
1961 /* The symbol from a DT_NEEDED object is referenced from
1962 the regular object to create a dynamic executable. We
1963 have to make sure there is a DT_NEEDED entry for it. */
1964
1965 dt_needed = false;
1966 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1967 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
1968 elf_dt_soname (abfd),
1969 true, false);
1970 if (strindex == (bfd_size_type) -1)
1971 goto error_return;
1972
1973 if (oldsize
1974 == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1975 {
1976 asection *sdyn;
1977 Elf_External_Dyn *dyncon, *dynconend;
1978
1979 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1980 ".dynamic");
1981 BFD_ASSERT (sdyn != NULL);
1982
1983 dyncon = (Elf_External_Dyn *) sdyn->contents;
1984 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1985 sdyn->_raw_size);
1986 for (; dyncon < dynconend; dyncon++)
1987 {
1988 Elf_Internal_Dyn dyn;
1989
1990 elf_swap_dyn_in (elf_hash_table (info)->dynobj,
1991 dyncon, &dyn);
1992 BFD_ASSERT (dyn.d_tag != DT_NEEDED ||
1993 dyn.d_un.d_val != strindex);
1994 }
1995 }
1996
1997 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1998 goto error_return;
1999 }
2000 }
2001 }
2002
2003 /* Now set the weakdefs field correctly for all the weak defined
2004 symbols we found. The only way to do this is to search all the
2005 symbols. Since we only need the information for non functions in
2006 dynamic objects, that's the only time we actually put anything on
2007 the list WEAKS. We need this information so that if a regular
2008 object refers to a symbol defined weakly in a dynamic object, the
2009 real symbol in the dynamic object is also put in the dynamic
2010 symbols; we also must arrange for both symbols to point to the
2011 same memory location. We could handle the general case of symbol
2012 aliasing, but a general symbol alias can only be generated in
2013 assembler code, handling it correctly would be very time
2014 consuming, and other ELF linkers don't handle general aliasing
2015 either. */
2016 while (weaks != NULL)
2017 {
2018 struct elf_link_hash_entry *hlook;
2019 asection *slook;
2020 bfd_vma vlook;
2021 struct elf_link_hash_entry **hpp;
2022 struct elf_link_hash_entry **hppend;
2023
2024 hlook = weaks;
2025 weaks = hlook->weakdef;
2026 hlook->weakdef = NULL;
2027
2028 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
2029 || hlook->root.type == bfd_link_hash_defweak
2030 || hlook->root.type == bfd_link_hash_common
2031 || hlook->root.type == bfd_link_hash_indirect);
2032 slook = hlook->root.u.def.section;
2033 vlook = hlook->root.u.def.value;
2034
2035 hpp = elf_sym_hashes (abfd);
2036 hppend = hpp + extsymcount;
2037 for (; hpp < hppend; hpp++)
2038 {
2039 struct elf_link_hash_entry *h;
2040
2041 h = *hpp;
2042 if (h != NULL && h != hlook
2043 && h->root.type == bfd_link_hash_defined
2044 && h->root.u.def.section == slook
2045 && h->root.u.def.value == vlook)
2046 {
2047 hlook->weakdef = h;
2048
2049 /* If the weak definition is in the list of dynamic
2050 symbols, make sure the real definition is put there
2051 as well. */
2052 if (hlook->dynindx != -1
2053 && h->dynindx == -1)
2054 {
2055 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2056 goto error_return;
2057 }
2058
2059 /* If the real definition is in the list of dynamic
2060 symbols, make sure the weak definition is put there
2061 as well. If we don't do this, then the dynamic
2062 loader might not merge the entries for the real
2063 definition and the weak definition. */
2064 if (h->dynindx != -1
2065 && hlook->dynindx == -1)
2066 {
2067 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
2068 goto error_return;
2069 }
2070
2071 break;
2072 }
2073 }
2074 }
2075
2076 if (buf != NULL)
2077 {
2078 free (buf);
2079 buf = NULL;
2080 }
2081
2082 if (extversym != NULL)
2083 {
2084 free (extversym);
2085 extversym = NULL;
2086 }
2087
2088 /* If this object is the same format as the output object, and it is
2089 not a shared library, then let the backend look through the
2090 relocs.
2091
2092 This is required to build global offset table entries and to
2093 arrange for dynamic relocs. It is not required for the
2094 particular common case of linking non PIC code, even when linking
2095 against shared libraries, but unfortunately there is no way of
2096 knowing whether an object file has been compiled PIC or not.
2097 Looking through the relocs is not particularly time consuming.
2098 The problem is that we must either (1) keep the relocs in memory,
2099 which causes the linker to require additional runtime memory or
2100 (2) read the relocs twice from the input file, which wastes time.
2101 This would be a good case for using mmap.
2102
2103 I have no idea how to handle linking PIC code into a file of a
2104 different format. It probably can't be done. */
2105 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2106 if (! dynamic
2107 && abfd->xvec == info->hash->creator
2108 && check_relocs != NULL)
2109 {
2110 asection *o;
2111
2112 for (o = abfd->sections; o != NULL; o = o->next)
2113 {
2114 Elf_Internal_Rela *internal_relocs;
2115 boolean ok;
2116
2117 if ((o->flags & SEC_RELOC) == 0
2118 || o->reloc_count == 0
2119 || ((info->strip == strip_all || info->strip == strip_debugger)
2120 && (o->flags & SEC_DEBUGGING) != 0)
2121 || bfd_is_abs_section (o->output_section))
2122 continue;
2123
2124 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2125 (abfd, o, (PTR) NULL,
2126 (Elf_Internal_Rela *) NULL,
2127 info->keep_memory));
2128 if (internal_relocs == NULL)
2129 goto error_return;
2130
2131 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2132
2133 if (! info->keep_memory)
2134 free (internal_relocs);
2135
2136 if (! ok)
2137 goto error_return;
2138 }
2139 }
2140
2141 /* If this is a non-traditional, non-relocateable link, try to
2142 optimize the handling of the .stab/.stabstr sections. */
2143 if (! dynamic
2144 && ! info->relocateable
2145 && ! info->traditional_format
2146 && info->hash->creator->flavour == bfd_target_elf_flavour
2147 && (info->strip != strip_all && info->strip != strip_debugger))
2148 {
2149 asection *stab, *stabstr;
2150
2151 stab = bfd_get_section_by_name (abfd, ".stab");
2152 if (stab != NULL)
2153 {
2154 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2155
2156 if (stabstr != NULL)
2157 {
2158 struct bfd_elf_section_data *secdata;
2159
2160 secdata = elf_section_data (stab);
2161 if (! _bfd_link_section_stabs (abfd,
2162 &elf_hash_table (info)->stab_info,
2163 stab, stabstr,
2164 &secdata->stab_info))
2165 goto error_return;
2166 }
2167 }
2168 }
2169
2170 if (! info->relocateable && ! dynamic)
2171 {
2172 asection *s;
2173
2174 for (s = abfd->sections; s != NULL; s = s->next)
2175 if ((s->flags & SEC_MERGE)
2176 && ! _bfd_merge_section (abfd,
2177 &elf_hash_table (info)->merge_info,
2178 s, &elf_section_data (s)->merge_info))
2179 goto error_return;
2180 }
2181
2182 return true;
2183
2184 error_return:
2185 if (buf != NULL)
2186 free (buf);
2187 if (dynbuf != NULL)
2188 free (dynbuf);
2189 if (dynver != NULL)
2190 free (dynver);
2191 if (extversym != NULL)
2192 free (extversym);
2193 return false;
2194 }
2195
2196 /* Create some sections which will be filled in with dynamic linking
2197 information. ABFD is an input file which requires dynamic sections
2198 to be created. The dynamic sections take up virtual memory space
2199 when the final executable is run, so we need to create them before
2200 addresses are assigned to the output sections. We work out the
2201 actual contents and size of these sections later. */
2202
2203 boolean
2204 elf_link_create_dynamic_sections (abfd, info)
2205 bfd *abfd;
2206 struct bfd_link_info *info;
2207 {
2208 flagword flags;
2209 register asection *s;
2210 struct elf_link_hash_entry *h;
2211 struct elf_backend_data *bed;
2212
2213 if (elf_hash_table (info)->dynamic_sections_created)
2214 return true;
2215
2216 /* Make sure that all dynamic sections use the same input BFD. */
2217 if (elf_hash_table (info)->dynobj == NULL)
2218 elf_hash_table (info)->dynobj = abfd;
2219 else
2220 abfd = elf_hash_table (info)->dynobj;
2221
2222 /* Note that we set the SEC_IN_MEMORY flag for all of these
2223 sections. */
2224 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2225 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2226
2227 /* A dynamically linked executable has a .interp section, but a
2228 shared library does not. */
2229 if (! info->shared)
2230 {
2231 s = bfd_make_section (abfd, ".interp");
2232 if (s == NULL
2233 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2234 return false;
2235 }
2236
2237 /* Create sections to hold version informations. These are removed
2238 if they are not needed. */
2239 s = bfd_make_section (abfd, ".gnu.version_d");
2240 if (s == NULL
2241 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2242 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2243 return false;
2244
2245 s = bfd_make_section (abfd, ".gnu.version");
2246 if (s == NULL
2247 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2248 || ! bfd_set_section_alignment (abfd, s, 1))
2249 return false;
2250
2251 s = bfd_make_section (abfd, ".gnu.version_r");
2252 if (s == NULL
2253 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2254 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2255 return false;
2256
2257 s = bfd_make_section (abfd, ".dynsym");
2258 if (s == NULL
2259 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2260 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2261 return false;
2262
2263 s = bfd_make_section (abfd, ".dynstr");
2264 if (s == NULL
2265 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2266 return false;
2267
2268 /* Create a strtab to hold the dynamic symbol names. */
2269 if (elf_hash_table (info)->dynstr == NULL)
2270 {
2271 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2272 if (elf_hash_table (info)->dynstr == NULL)
2273 return false;
2274 }
2275
2276 s = bfd_make_section (abfd, ".dynamic");
2277 if (s == NULL
2278 || ! bfd_set_section_flags (abfd, s, flags)
2279 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2280 return false;
2281
2282 /* The special symbol _DYNAMIC is always set to the start of the
2283 .dynamic section. This call occurs before we have processed the
2284 symbols for any dynamic object, so we don't have to worry about
2285 overriding a dynamic definition. We could set _DYNAMIC in a
2286 linker script, but we only want to define it if we are, in fact,
2287 creating a .dynamic section. We don't want to define it if there
2288 is no .dynamic section, since on some ELF platforms the start up
2289 code examines it to decide how to initialize the process. */
2290 h = NULL;
2291 if (! (_bfd_generic_link_add_one_symbol
2292 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2293 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2294 (struct bfd_link_hash_entry **) &h)))
2295 return false;
2296 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2297 h->type = STT_OBJECT;
2298
2299 if (info->shared
2300 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2301 return false;
2302
2303 bed = get_elf_backend_data (abfd);
2304
2305 s = bfd_make_section (abfd, ".hash");
2306 if (s == NULL
2307 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2308 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2309 return false;
2310 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2311
2312 /* Let the backend create the rest of the sections. This lets the
2313 backend set the right flags. The backend will normally create
2314 the .got and .plt sections. */
2315 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2316 return false;
2317
2318 elf_hash_table (info)->dynamic_sections_created = true;
2319
2320 return true;
2321 }
2322
2323 /* Add an entry to the .dynamic table. */
2324
2325 boolean
2326 elf_add_dynamic_entry (info, tag, val)
2327 struct bfd_link_info *info;
2328 bfd_vma tag;
2329 bfd_vma val;
2330 {
2331 Elf_Internal_Dyn dyn;
2332 bfd *dynobj;
2333 asection *s;
2334 size_t newsize;
2335 bfd_byte *newcontents;
2336
2337 dynobj = elf_hash_table (info)->dynobj;
2338
2339 s = bfd_get_section_by_name (dynobj, ".dynamic");
2340 BFD_ASSERT (s != NULL);
2341
2342 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2343 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2344 if (newcontents == NULL)
2345 return false;
2346
2347 dyn.d_tag = tag;
2348 dyn.d_un.d_val = val;
2349 elf_swap_dyn_out (dynobj, &dyn,
2350 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2351
2352 s->_raw_size = newsize;
2353 s->contents = newcontents;
2354
2355 return true;
2356 }
2357
2358 /* Record a new local dynamic symbol. */
2359
2360 boolean
2361 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2362 struct bfd_link_info *info;
2363 bfd *input_bfd;
2364 long input_indx;
2365 {
2366 struct elf_link_local_dynamic_entry *entry;
2367 struct elf_link_hash_table *eht;
2368 struct bfd_strtab_hash *dynstr;
2369 Elf_External_Sym esym;
2370 unsigned long dynstr_index;
2371 char *name;
2372
2373 /* See if the entry exists already. */
2374 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2375 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2376 return true;
2377
2378 entry = (struct elf_link_local_dynamic_entry *)
2379 bfd_alloc (input_bfd, sizeof (*entry));
2380 if (entry == NULL)
2381 return false;
2382
2383 /* Go find the symbol, so that we can find it's name. */
2384 if (bfd_seek (input_bfd,
2385 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2386 + input_indx * sizeof (Elf_External_Sym)),
2387 SEEK_SET) != 0
2388 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2389 != sizeof (Elf_External_Sym)))
2390 return false;
2391 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2392
2393 name = (bfd_elf_string_from_elf_section
2394 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2395 entry->isym.st_name));
2396
2397 dynstr = elf_hash_table (info)->dynstr;
2398 if (dynstr == NULL)
2399 {
2400 /* Create a strtab to hold the dynamic symbol names. */
2401 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2402 if (dynstr == NULL)
2403 return false;
2404 }
2405
2406 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2407 if (dynstr_index == (unsigned long) -1)
2408 return false;
2409 entry->isym.st_name = dynstr_index;
2410
2411 eht = elf_hash_table (info);
2412
2413 entry->next = eht->dynlocal;
2414 eht->dynlocal = entry;
2415 entry->input_bfd = input_bfd;
2416 entry->input_indx = input_indx;
2417 eht->dynsymcount++;
2418
2419 /* Whatever binding the symbol had before, it's now local. */
2420 entry->isym.st_info
2421 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2422
2423 /* The dynindx will be set at the end of size_dynamic_sections. */
2424
2425 return true;
2426 }
2427 \f
2428 /* Read and swap the relocs from the section indicated by SHDR. This
2429 may be either a REL or a RELA section. The relocations are
2430 translated into RELA relocations and stored in INTERNAL_RELOCS,
2431 which should have already been allocated to contain enough space.
2432 The EXTERNAL_RELOCS are a buffer where the external form of the
2433 relocations should be stored.
2434
2435 Returns false if something goes wrong. */
2436
2437 static boolean
2438 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2439 internal_relocs)
2440 bfd *abfd;
2441 Elf_Internal_Shdr *shdr;
2442 PTR external_relocs;
2443 Elf_Internal_Rela *internal_relocs;
2444 {
2445 struct elf_backend_data *bed;
2446
2447 /* If there aren't any relocations, that's OK. */
2448 if (!shdr)
2449 return true;
2450
2451 /* Position ourselves at the start of the section. */
2452 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2453 return false;
2454
2455 /* Read the relocations. */
2456 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2457 != shdr->sh_size)
2458 return false;
2459
2460 bed = get_elf_backend_data (abfd);
2461
2462 /* Convert the external relocations to the internal format. */
2463 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2464 {
2465 Elf_External_Rel *erel;
2466 Elf_External_Rel *erelend;
2467 Elf_Internal_Rela *irela;
2468 Elf_Internal_Rel *irel;
2469
2470 erel = (Elf_External_Rel *) external_relocs;
2471 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2472 irela = internal_relocs;
2473 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2474 * sizeof (Elf_Internal_Rel)));
2475 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2476 {
2477 unsigned char i;
2478
2479 if (bed->s->swap_reloc_in)
2480 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2481 else
2482 elf_swap_reloc_in (abfd, erel, irel);
2483
2484 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2485 {
2486 irela[i].r_offset = irel[i].r_offset;
2487 irela[i].r_info = irel[i].r_info;
2488 irela[i].r_addend = 0;
2489 }
2490 }
2491 }
2492 else
2493 {
2494 Elf_External_Rela *erela;
2495 Elf_External_Rela *erelaend;
2496 Elf_Internal_Rela *irela;
2497
2498 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2499
2500 erela = (Elf_External_Rela *) external_relocs;
2501 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2502 irela = internal_relocs;
2503 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2504 {
2505 if (bed->s->swap_reloca_in)
2506 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2507 else
2508 elf_swap_reloca_in (abfd, erela, irela);
2509 }
2510 }
2511
2512 return true;
2513 }
2514
2515 /* Read and swap the relocs for a section O. They may have been
2516 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2517 not NULL, they are used as buffers to read into. They are known to
2518 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2519 the return value is allocated using either malloc or bfd_alloc,
2520 according to the KEEP_MEMORY argument. If O has two relocation
2521 sections (both REL and RELA relocations), then the REL_HDR
2522 relocations will appear first in INTERNAL_RELOCS, followed by the
2523 REL_HDR2 relocations. */
2524
2525 Elf_Internal_Rela *
2526 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2527 keep_memory)
2528 bfd *abfd;
2529 asection *o;
2530 PTR external_relocs;
2531 Elf_Internal_Rela *internal_relocs;
2532 boolean keep_memory;
2533 {
2534 Elf_Internal_Shdr *rel_hdr;
2535 PTR alloc1 = NULL;
2536 Elf_Internal_Rela *alloc2 = NULL;
2537 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2538
2539 if (elf_section_data (o)->relocs != NULL)
2540 return elf_section_data (o)->relocs;
2541
2542 if (o->reloc_count == 0)
2543 return NULL;
2544
2545 rel_hdr = &elf_section_data (o)->rel_hdr;
2546
2547 if (internal_relocs == NULL)
2548 {
2549 size_t size;
2550
2551 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2552 * sizeof (Elf_Internal_Rela));
2553 if (keep_memory)
2554 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2555 else
2556 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2557 if (internal_relocs == NULL)
2558 goto error_return;
2559 }
2560
2561 if (external_relocs == NULL)
2562 {
2563 size_t size = (size_t) rel_hdr->sh_size;
2564
2565 if (elf_section_data (o)->rel_hdr2)
2566 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2567 alloc1 = (PTR) bfd_malloc (size);
2568 if (alloc1 == NULL)
2569 goto error_return;
2570 external_relocs = alloc1;
2571 }
2572
2573 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2574 external_relocs,
2575 internal_relocs))
2576 goto error_return;
2577 if (!elf_link_read_relocs_from_section
2578 (abfd,
2579 elf_section_data (o)->rel_hdr2,
2580 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2581 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2582 * bed->s->int_rels_per_ext_rel)))
2583 goto error_return;
2584
2585 /* Cache the results for next time, if we can. */
2586 if (keep_memory)
2587 elf_section_data (o)->relocs = internal_relocs;
2588
2589 if (alloc1 != NULL)
2590 free (alloc1);
2591
2592 /* Don't free alloc2, since if it was allocated we are passing it
2593 back (under the name of internal_relocs). */
2594
2595 return internal_relocs;
2596
2597 error_return:
2598 if (alloc1 != NULL)
2599 free (alloc1);
2600 if (alloc2 != NULL)
2601 free (alloc2);
2602 return NULL;
2603 }
2604 \f
2605 /* Record an assignment to a symbol made by a linker script. We need
2606 this in case some dynamic object refers to this symbol. */
2607
2608 /*ARGSUSED*/
2609 boolean
2610 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2611 bfd *output_bfd ATTRIBUTE_UNUSED;
2612 struct bfd_link_info *info;
2613 const char *name;
2614 boolean provide;
2615 {
2616 struct elf_link_hash_entry *h;
2617
2618 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2619 return true;
2620
2621 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2622 if (h == NULL)
2623 return false;
2624
2625 if (h->root.type == bfd_link_hash_new)
2626 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2627
2628 /* If this symbol is being provided by the linker script, and it is
2629 currently defined by a dynamic object, but not by a regular
2630 object, then mark it as undefined so that the generic linker will
2631 force the correct value. */
2632 if (provide
2633 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2634 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2635 h->root.type = bfd_link_hash_undefined;
2636
2637 /* If this symbol is not being provided by the linker script, and it is
2638 currently defined by a dynamic object, but not by a regular object,
2639 then clear out any version information because the symbol will not be
2640 associated with the dynamic object any more. */
2641 if (!provide
2642 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2643 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2644 h->verinfo.verdef = NULL;
2645
2646 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2647
2648 /* When possible, keep the original type of the symbol */
2649 if (h->type == STT_NOTYPE)
2650 h->type = STT_OBJECT;
2651
2652 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2653 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2654 || info->shared)
2655 && h->dynindx == -1)
2656 {
2657 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2658 return false;
2659
2660 /* If this is a weak defined symbol, and we know a corresponding
2661 real symbol from the same dynamic object, make sure the real
2662 symbol is also made into a dynamic symbol. */
2663 if (h->weakdef != NULL
2664 && h->weakdef->dynindx == -1)
2665 {
2666 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2667 return false;
2668 }
2669 }
2670
2671 return true;
2672 }
2673 \f
2674 /* This structure is used to pass information to
2675 elf_link_assign_sym_version. */
2676
2677 struct elf_assign_sym_version_info
2678 {
2679 /* Output BFD. */
2680 bfd *output_bfd;
2681 /* General link information. */
2682 struct bfd_link_info *info;
2683 /* Version tree. */
2684 struct bfd_elf_version_tree *verdefs;
2685 /* Whether we are exporting all dynamic symbols. */
2686 boolean export_dynamic;
2687 /* Whether we had a failure. */
2688 boolean failed;
2689 };
2690
2691 /* This structure is used to pass information to
2692 elf_link_find_version_dependencies. */
2693
2694 struct elf_find_verdep_info
2695 {
2696 /* Output BFD. */
2697 bfd *output_bfd;
2698 /* General link information. */
2699 struct bfd_link_info *info;
2700 /* The number of dependencies. */
2701 unsigned int vers;
2702 /* Whether we had a failure. */
2703 boolean failed;
2704 };
2705
2706 /* Array used to determine the number of hash table buckets to use
2707 based on the number of symbols there are. If there are fewer than
2708 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2709 fewer than 37 we use 17 buckets, and so forth. We never use more
2710 than 32771 buckets. */
2711
2712 static const size_t elf_buckets[] =
2713 {
2714 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2715 16411, 32771, 0
2716 };
2717
2718 /* Compute bucket count for hashing table. We do not use a static set
2719 of possible tables sizes anymore. Instead we determine for all
2720 possible reasonable sizes of the table the outcome (i.e., the
2721 number of collisions etc) and choose the best solution. The
2722 weighting functions are not too simple to allow the table to grow
2723 without bounds. Instead one of the weighting factors is the size.
2724 Therefore the result is always a good payoff between few collisions
2725 (= short chain lengths) and table size. */
2726 static size_t
2727 compute_bucket_count (info)
2728 struct bfd_link_info *info;
2729 {
2730 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2731 size_t best_size = 0;
2732 unsigned long int *hashcodes;
2733 unsigned long int *hashcodesp;
2734 unsigned long int i;
2735
2736 /* Compute the hash values for all exported symbols. At the same
2737 time store the values in an array so that we could use them for
2738 optimizations. */
2739 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2740 * sizeof (unsigned long int));
2741 if (hashcodes == NULL)
2742 return 0;
2743 hashcodesp = hashcodes;
2744
2745 /* Put all hash values in HASHCODES. */
2746 elf_link_hash_traverse (elf_hash_table (info),
2747 elf_collect_hash_codes, &hashcodesp);
2748
2749 /* We have a problem here. The following code to optimize the table
2750 size requires an integer type with more the 32 bits. If
2751 BFD_HOST_U_64_BIT is set we know about such a type. */
2752 #ifdef BFD_HOST_U_64_BIT
2753 if (info->optimize == true)
2754 {
2755 unsigned long int nsyms = hashcodesp - hashcodes;
2756 size_t minsize;
2757 size_t maxsize;
2758 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2759 unsigned long int *counts ;
2760
2761 /* Possible optimization parameters: if we have NSYMS symbols we say
2762 that the hashing table must at least have NSYMS/4 and at most
2763 2*NSYMS buckets. */
2764 minsize = nsyms / 4;
2765 if (minsize == 0)
2766 minsize = 1;
2767 best_size = maxsize = nsyms * 2;
2768
2769 /* Create array where we count the collisions in. We must use bfd_malloc
2770 since the size could be large. */
2771 counts = (unsigned long int *) bfd_malloc (maxsize
2772 * sizeof (unsigned long int));
2773 if (counts == NULL)
2774 {
2775 free (hashcodes);
2776 return 0;
2777 }
2778
2779 /* Compute the "optimal" size for the hash table. The criteria is a
2780 minimal chain length. The minor criteria is (of course) the size
2781 of the table. */
2782 for (i = minsize; i < maxsize; ++i)
2783 {
2784 /* Walk through the array of hashcodes and count the collisions. */
2785 BFD_HOST_U_64_BIT max;
2786 unsigned long int j;
2787 unsigned long int fact;
2788
2789 memset (counts, '\0', i * sizeof (unsigned long int));
2790
2791 /* Determine how often each hash bucket is used. */
2792 for (j = 0; j < nsyms; ++j)
2793 ++counts[hashcodes[j] % i];
2794
2795 /* For the weight function we need some information about the
2796 pagesize on the target. This is information need not be 100%
2797 accurate. Since this information is not available (so far) we
2798 define it here to a reasonable default value. If it is crucial
2799 to have a better value some day simply define this value. */
2800 # ifndef BFD_TARGET_PAGESIZE
2801 # define BFD_TARGET_PAGESIZE (4096)
2802 # endif
2803
2804 /* We in any case need 2 + NSYMS entries for the size values and
2805 the chains. */
2806 max = (2 + nsyms) * (ARCH_SIZE / 8);
2807
2808 # if 1
2809 /* Variant 1: optimize for short chains. We add the squares
2810 of all the chain lengths (which favous many small chain
2811 over a few long chains). */
2812 for (j = 0; j < i; ++j)
2813 max += counts[j] * counts[j];
2814
2815 /* This adds penalties for the overall size of the table. */
2816 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2817 max *= fact * fact;
2818 # else
2819 /* Variant 2: Optimize a lot more for small table. Here we
2820 also add squares of the size but we also add penalties for
2821 empty slots (the +1 term). */
2822 for (j = 0; j < i; ++j)
2823 max += (1 + counts[j]) * (1 + counts[j]);
2824
2825 /* The overall size of the table is considered, but not as
2826 strong as in variant 1, where it is squared. */
2827 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2828 max *= fact;
2829 # endif
2830
2831 /* Compare with current best results. */
2832 if (max < best_chlen)
2833 {
2834 best_chlen = max;
2835 best_size = i;
2836 }
2837 }
2838
2839 free (counts);
2840 }
2841 else
2842 #endif /* defined (BFD_HOST_U_64_BIT) */
2843 {
2844 /* This is the fallback solution if no 64bit type is available or if we
2845 are not supposed to spend much time on optimizations. We select the
2846 bucket count using a fixed set of numbers. */
2847 for (i = 0; elf_buckets[i] != 0; i++)
2848 {
2849 best_size = elf_buckets[i];
2850 if (dynsymcount < elf_buckets[i + 1])
2851 break;
2852 }
2853 }
2854
2855 /* Free the arrays we needed. */
2856 free (hashcodes);
2857
2858 return best_size;
2859 }
2860
2861 /* Set up the sizes and contents of the ELF dynamic sections. This is
2862 called by the ELF linker emulation before_allocation routine. We
2863 must set the sizes of the sections before the linker sets the
2864 addresses of the various sections. */
2865
2866 boolean
2867 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2868 export_dynamic, filter_shlib,
2869 auxiliary_filters, info, sinterpptr,
2870 verdefs)
2871 bfd *output_bfd;
2872 const char *soname;
2873 const char *rpath;
2874 boolean export_dynamic;
2875 const char *filter_shlib;
2876 const char * const *auxiliary_filters;
2877 struct bfd_link_info *info;
2878 asection **sinterpptr;
2879 struct bfd_elf_version_tree *verdefs;
2880 {
2881 bfd_size_type soname_indx;
2882 bfd *dynobj;
2883 struct elf_backend_data *bed;
2884 struct elf_assign_sym_version_info asvinfo;
2885
2886 *sinterpptr = NULL;
2887
2888 soname_indx = (bfd_size_type) -1;
2889
2890 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2891 return true;
2892
2893 /* The backend may have to create some sections regardless of whether
2894 we're dynamic or not. */
2895 bed = get_elf_backend_data (output_bfd);
2896 if (bed->elf_backend_always_size_sections
2897 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2898 return false;
2899
2900 dynobj = elf_hash_table (info)->dynobj;
2901
2902 /* If there were no dynamic objects in the link, there is nothing to
2903 do here. */
2904 if (dynobj == NULL)
2905 return true;
2906
2907 if (elf_hash_table (info)->dynamic_sections_created)
2908 {
2909 struct elf_info_failed eif;
2910 struct elf_link_hash_entry *h;
2911 asection *dynstr;
2912
2913 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2914 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2915
2916 if (soname != NULL)
2917 {
2918 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2919 soname, true, true);
2920 if (soname_indx == (bfd_size_type) -1
2921 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2922 return false;
2923 }
2924
2925 if (info->symbolic)
2926 {
2927 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2928 return false;
2929 info->flags |= DF_SYMBOLIC;
2930 }
2931
2932 if (rpath != NULL)
2933 {
2934 bfd_size_type indx;
2935
2936 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2937 true, true);
2938 if (indx == (bfd_size_type) -1
2939 || ! elf_add_dynamic_entry (info, DT_RPATH, indx)
2940 || (info->new_dtags
2941 && ! elf_add_dynamic_entry (info, DT_RUNPATH, indx)))
2942 return false;
2943 }
2944
2945 if (filter_shlib != NULL)
2946 {
2947 bfd_size_type indx;
2948
2949 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2950 filter_shlib, true, true);
2951 if (indx == (bfd_size_type) -1
2952 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2953 return false;
2954 }
2955
2956 if (auxiliary_filters != NULL)
2957 {
2958 const char * const *p;
2959
2960 for (p = auxiliary_filters; *p != NULL; p++)
2961 {
2962 bfd_size_type indx;
2963
2964 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2965 *p, true, true);
2966 if (indx == (bfd_size_type) -1
2967 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2968 return false;
2969 }
2970 }
2971
2972 eif.info = info;
2973 eif.failed = false;
2974
2975 /* If we are supposed to export all symbols into the dynamic symbol
2976 table (this is not the normal case), then do so. */
2977 if (export_dynamic)
2978 {
2979 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2980 (PTR) &eif);
2981 if (eif.failed)
2982 return false;
2983 }
2984
2985 /* Attach all the symbols to their version information. */
2986 asvinfo.output_bfd = output_bfd;
2987 asvinfo.info = info;
2988 asvinfo.verdefs = verdefs;
2989 asvinfo.export_dynamic = export_dynamic;
2990 asvinfo.failed = false;
2991
2992 elf_link_hash_traverse (elf_hash_table (info),
2993 elf_link_assign_sym_version,
2994 (PTR) &asvinfo);
2995 if (asvinfo.failed)
2996 return false;
2997
2998 /* Find all symbols which were defined in a dynamic object and make
2999 the backend pick a reasonable value for them. */
3000 elf_link_hash_traverse (elf_hash_table (info),
3001 elf_adjust_dynamic_symbol,
3002 (PTR) &eif);
3003 if (eif.failed)
3004 return false;
3005
3006 /* Add some entries to the .dynamic section. We fill in some of the
3007 values later, in elf_bfd_final_link, but we must add the entries
3008 now so that we know the final size of the .dynamic section. */
3009
3010 /* If there are initialization and/or finalization functions to
3011 call then add the corresponding DT_INIT/DT_FINI entries. */
3012 h = (info->init_function
3013 ? elf_link_hash_lookup (elf_hash_table (info),
3014 info->init_function, false,
3015 false, false)
3016 : NULL);
3017 if (h != NULL
3018 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3019 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3020 {
3021 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
3022 return false;
3023 }
3024 h = (info->fini_function
3025 ? elf_link_hash_lookup (elf_hash_table (info),
3026 info->fini_function, false,
3027 false, false)
3028 : NULL);
3029 if (h != NULL
3030 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3031 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3032 {
3033 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
3034 return false;
3035 }
3036
3037 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
3038 /* If .dynstr is excluded from the link, we don't want any of
3039 these tags. Strictly, we should be checking each section
3040 individually; This quick check covers for the case where
3041 someone does a /DISCARD/ : { *(*) }. */
3042 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
3043 {
3044 bfd_size_type strsize;
3045
3046 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3047 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
3048 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
3049 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
3050 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
3051 || ! elf_add_dynamic_entry (info, DT_SYMENT,
3052 sizeof (Elf_External_Sym)))
3053 return false;
3054 }
3055 }
3056
3057 /* The backend must work out the sizes of all the other dynamic
3058 sections. */
3059 if (bed->elf_backend_size_dynamic_sections
3060 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
3061 return false;
3062
3063 if (elf_hash_table (info)->dynamic_sections_created)
3064 {
3065 size_t dynsymcount;
3066 asection *s;
3067 size_t bucketcount = 0;
3068 size_t hash_entry_size;
3069
3070 /* Set up the version definition section. */
3071 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3072 BFD_ASSERT (s != NULL);
3073
3074 /* We may have created additional version definitions if we are
3075 just linking a regular application. */
3076 verdefs = asvinfo.verdefs;
3077
3078 if (verdefs == NULL)
3079 _bfd_strip_section_from_output (info, s);
3080 else
3081 {
3082 unsigned int cdefs;
3083 bfd_size_type size;
3084 struct bfd_elf_version_tree *t;
3085 bfd_byte *p;
3086 Elf_Internal_Verdef def;
3087 Elf_Internal_Verdaux defaux;
3088
3089 cdefs = 0;
3090 size = 0;
3091
3092 /* Make space for the base version. */
3093 size += sizeof (Elf_External_Verdef);
3094 size += sizeof (Elf_External_Verdaux);
3095 ++cdefs;
3096
3097 for (t = verdefs; t != NULL; t = t->next)
3098 {
3099 struct bfd_elf_version_deps *n;
3100
3101 size += sizeof (Elf_External_Verdef);
3102 size += sizeof (Elf_External_Verdaux);
3103 ++cdefs;
3104
3105 for (n = t->deps; n != NULL; n = n->next)
3106 size += sizeof (Elf_External_Verdaux);
3107 }
3108
3109 s->_raw_size = size;
3110 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3111 if (s->contents == NULL && s->_raw_size != 0)
3112 return false;
3113
3114 /* Fill in the version definition section. */
3115
3116 p = s->contents;
3117
3118 def.vd_version = VER_DEF_CURRENT;
3119 def.vd_flags = VER_FLG_BASE;
3120 def.vd_ndx = 1;
3121 def.vd_cnt = 1;
3122 def.vd_aux = sizeof (Elf_External_Verdef);
3123 def.vd_next = (sizeof (Elf_External_Verdef)
3124 + sizeof (Elf_External_Verdaux));
3125
3126 if (soname_indx != (bfd_size_type) -1)
3127 {
3128 def.vd_hash = bfd_elf_hash (soname);
3129 defaux.vda_name = soname_indx;
3130 }
3131 else
3132 {
3133 const char *name;
3134 bfd_size_type indx;
3135
3136 name = output_bfd->filename;
3137 def.vd_hash = bfd_elf_hash (name);
3138 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3139 name, true, false);
3140 if (indx == (bfd_size_type) -1)
3141 return false;
3142 defaux.vda_name = indx;
3143 }
3144 defaux.vda_next = 0;
3145
3146 _bfd_elf_swap_verdef_out (output_bfd, &def,
3147 (Elf_External_Verdef *)p);
3148 p += sizeof (Elf_External_Verdef);
3149 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3150 (Elf_External_Verdaux *) p);
3151 p += sizeof (Elf_External_Verdaux);
3152
3153 for (t = verdefs; t != NULL; t = t->next)
3154 {
3155 unsigned int cdeps;
3156 struct bfd_elf_version_deps *n;
3157 struct elf_link_hash_entry *h;
3158
3159 cdeps = 0;
3160 for (n = t->deps; n != NULL; n = n->next)
3161 ++cdeps;
3162
3163 /* Add a symbol representing this version. */
3164 h = NULL;
3165 if (! (_bfd_generic_link_add_one_symbol
3166 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3167 (bfd_vma) 0, (const char *) NULL, false,
3168 get_elf_backend_data (dynobj)->collect,
3169 (struct bfd_link_hash_entry **) &h)))
3170 return false;
3171 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3172 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3173 h->type = STT_OBJECT;
3174 h->verinfo.vertree = t;
3175
3176 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3177 return false;
3178
3179 def.vd_version = VER_DEF_CURRENT;
3180 def.vd_flags = 0;
3181 if (t->globals == NULL && t->locals == NULL && ! t->used)
3182 def.vd_flags |= VER_FLG_WEAK;
3183 def.vd_ndx = t->vernum + 1;
3184 def.vd_cnt = cdeps + 1;
3185 def.vd_hash = bfd_elf_hash (t->name);
3186 def.vd_aux = sizeof (Elf_External_Verdef);
3187 if (t->next != NULL)
3188 def.vd_next = (sizeof (Elf_External_Verdef)
3189 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3190 else
3191 def.vd_next = 0;
3192
3193 _bfd_elf_swap_verdef_out (output_bfd, &def,
3194 (Elf_External_Verdef *) p);
3195 p += sizeof (Elf_External_Verdef);
3196
3197 defaux.vda_name = h->dynstr_index;
3198 if (t->deps == NULL)
3199 defaux.vda_next = 0;
3200 else
3201 defaux.vda_next = sizeof (Elf_External_Verdaux);
3202 t->name_indx = defaux.vda_name;
3203
3204 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3205 (Elf_External_Verdaux *) p);
3206 p += sizeof (Elf_External_Verdaux);
3207
3208 for (n = t->deps; n != NULL; n = n->next)
3209 {
3210 if (n->version_needed == NULL)
3211 {
3212 /* This can happen if there was an error in the
3213 version script. */
3214 defaux.vda_name = 0;
3215 }
3216 else
3217 defaux.vda_name = n->version_needed->name_indx;
3218 if (n->next == NULL)
3219 defaux.vda_next = 0;
3220 else
3221 defaux.vda_next = sizeof (Elf_External_Verdaux);
3222
3223 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3224 (Elf_External_Verdaux *) p);
3225 p += sizeof (Elf_External_Verdaux);
3226 }
3227 }
3228
3229 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3230 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3231 return false;
3232
3233 elf_tdata (output_bfd)->cverdefs = cdefs;
3234 }
3235
3236 if (info->new_dtags && info->flags)
3237 {
3238 if (! elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
3239 return false;
3240 }
3241
3242 if (info->flags_1)
3243 {
3244 if (! info->shared)
3245 info->flags_1 &= ~ (DF_1_INITFIRST
3246 | DF_1_NODELETE
3247 | DF_1_NOOPEN);
3248 if (! elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
3249 return false;
3250 }
3251
3252 /* Work out the size of the version reference section. */
3253
3254 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3255 BFD_ASSERT (s != NULL);
3256 {
3257 struct elf_find_verdep_info sinfo;
3258
3259 sinfo.output_bfd = output_bfd;
3260 sinfo.info = info;
3261 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3262 if (sinfo.vers == 0)
3263 sinfo.vers = 1;
3264 sinfo.failed = false;
3265
3266 elf_link_hash_traverse (elf_hash_table (info),
3267 elf_link_find_version_dependencies,
3268 (PTR) &sinfo);
3269
3270 if (elf_tdata (output_bfd)->verref == NULL)
3271 _bfd_strip_section_from_output (info, s);
3272 else
3273 {
3274 Elf_Internal_Verneed *t;
3275 unsigned int size;
3276 unsigned int crefs;
3277 bfd_byte *p;
3278
3279 /* Build the version definition section. */
3280 size = 0;
3281 crefs = 0;
3282 for (t = elf_tdata (output_bfd)->verref;
3283 t != NULL;
3284 t = t->vn_nextref)
3285 {
3286 Elf_Internal_Vernaux *a;
3287
3288 size += sizeof (Elf_External_Verneed);
3289 ++crefs;
3290 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3291 size += sizeof (Elf_External_Vernaux);
3292 }
3293
3294 s->_raw_size = size;
3295 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3296 if (s->contents == NULL)
3297 return false;
3298
3299 p = s->contents;
3300 for (t = elf_tdata (output_bfd)->verref;
3301 t != NULL;
3302 t = t->vn_nextref)
3303 {
3304 unsigned int caux;
3305 Elf_Internal_Vernaux *a;
3306 bfd_size_type indx;
3307
3308 caux = 0;
3309 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3310 ++caux;
3311
3312 t->vn_version = VER_NEED_CURRENT;
3313 t->vn_cnt = caux;
3314 if (elf_dt_name (t->vn_bfd) != NULL)
3315 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3316 elf_dt_name (t->vn_bfd),
3317 true, false);
3318 else
3319 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3320 t->vn_bfd->filename, true, false);
3321 if (indx == (bfd_size_type) -1)
3322 return false;
3323 t->vn_file = indx;
3324 t->vn_aux = sizeof (Elf_External_Verneed);
3325 if (t->vn_nextref == NULL)
3326 t->vn_next = 0;
3327 else
3328 t->vn_next = (sizeof (Elf_External_Verneed)
3329 + caux * sizeof (Elf_External_Vernaux));
3330
3331 _bfd_elf_swap_verneed_out (output_bfd, t,
3332 (Elf_External_Verneed *) p);
3333 p += sizeof (Elf_External_Verneed);
3334
3335 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3336 {
3337 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3338 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3339 a->vna_nodename, true, false);
3340 if (indx == (bfd_size_type) -1)
3341 return false;
3342 a->vna_name = indx;
3343 if (a->vna_nextptr == NULL)
3344 a->vna_next = 0;
3345 else
3346 a->vna_next = sizeof (Elf_External_Vernaux);
3347
3348 _bfd_elf_swap_vernaux_out (output_bfd, a,
3349 (Elf_External_Vernaux *) p);
3350 p += sizeof (Elf_External_Vernaux);
3351 }
3352 }
3353
3354 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3355 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3356 return false;
3357
3358 elf_tdata (output_bfd)->cverrefs = crefs;
3359 }
3360 }
3361
3362 /* Assign dynsym indicies. In a shared library we generate a
3363 section symbol for each output section, which come first.
3364 Next come all of the back-end allocated local dynamic syms,
3365 followed by the rest of the global symbols. */
3366
3367 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3368
3369 /* Work out the size of the symbol version section. */
3370 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3371 BFD_ASSERT (s != NULL);
3372 if (dynsymcount == 0
3373 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3374 {
3375 _bfd_strip_section_from_output (info, s);
3376 /* The DYNSYMCOUNT might have changed if we were going to
3377 output a dynamic symbol table entry for S. */
3378 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3379 }
3380 else
3381 {
3382 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3383 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3384 if (s->contents == NULL)
3385 return false;
3386
3387 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3388 return false;
3389 }
3390
3391 /* Set the size of the .dynsym and .hash sections. We counted
3392 the number of dynamic symbols in elf_link_add_object_symbols.
3393 We will build the contents of .dynsym and .hash when we build
3394 the final symbol table, because until then we do not know the
3395 correct value to give the symbols. We built the .dynstr
3396 section as we went along in elf_link_add_object_symbols. */
3397 s = bfd_get_section_by_name (dynobj, ".dynsym");
3398 BFD_ASSERT (s != NULL);
3399 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3400 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3401 if (s->contents == NULL && s->_raw_size != 0)
3402 return false;
3403
3404 if (dynsymcount != 0)
3405 {
3406 Elf_Internal_Sym isym;
3407
3408 /* The first entry in .dynsym is a dummy symbol. */
3409 isym.st_value = 0;
3410 isym.st_size = 0;
3411 isym.st_name = 0;
3412 isym.st_info = 0;
3413 isym.st_other = 0;
3414 isym.st_shndx = 0;
3415 elf_swap_symbol_out (output_bfd, &isym,
3416 (PTR) (Elf_External_Sym *) s->contents);
3417 }
3418
3419 /* Compute the size of the hashing table. As a side effect this
3420 computes the hash values for all the names we export. */
3421 bucketcount = compute_bucket_count (info);
3422
3423 s = bfd_get_section_by_name (dynobj, ".hash");
3424 BFD_ASSERT (s != NULL);
3425 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3426 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3427 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3428 if (s->contents == NULL)
3429 return false;
3430 memset (s->contents, 0, (size_t) s->_raw_size);
3431
3432 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3433 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3434 s->contents + hash_entry_size);
3435
3436 elf_hash_table (info)->bucketcount = bucketcount;
3437
3438 s = bfd_get_section_by_name (dynobj, ".dynstr");
3439 BFD_ASSERT (s != NULL);
3440 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3441
3442 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3443 return false;
3444 }
3445
3446 return true;
3447 }
3448 \f
3449 /* Fix up the flags for a symbol. This handles various cases which
3450 can only be fixed after all the input files are seen. This is
3451 currently called by both adjust_dynamic_symbol and
3452 assign_sym_version, which is unnecessary but perhaps more robust in
3453 the face of future changes. */
3454
3455 static boolean
3456 elf_fix_symbol_flags (h, eif)
3457 struct elf_link_hash_entry *h;
3458 struct elf_info_failed *eif;
3459 {
3460 /* If this symbol was mentioned in a non-ELF file, try to set
3461 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3462 permit a non-ELF file to correctly refer to a symbol defined in
3463 an ELF dynamic object. */
3464 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3465 {
3466 while (h->root.type == bfd_link_hash_indirect)
3467 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3468
3469 if (h->root.type != bfd_link_hash_defined
3470 && h->root.type != bfd_link_hash_defweak)
3471 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3472 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3473 else
3474 {
3475 if (h->root.u.def.section->owner != NULL
3476 && (bfd_get_flavour (h->root.u.def.section->owner)
3477 == bfd_target_elf_flavour))
3478 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3479 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3480 else
3481 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3482 }
3483
3484 if (h->dynindx == -1
3485 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3486 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3487 {
3488 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3489 {
3490 eif->failed = true;
3491 return false;
3492 }
3493 }
3494 }
3495 else
3496 {
3497 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3498 was first seen in a non-ELF file. Fortunately, if the symbol
3499 was first seen in an ELF file, we're probably OK unless the
3500 symbol was defined in a non-ELF file. Catch that case here.
3501 FIXME: We're still in trouble if the symbol was first seen in
3502 a dynamic object, and then later in a non-ELF regular object. */
3503 if ((h->root.type == bfd_link_hash_defined
3504 || h->root.type == bfd_link_hash_defweak)
3505 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3506 && (h->root.u.def.section->owner != NULL
3507 ? (bfd_get_flavour (h->root.u.def.section->owner)
3508 != bfd_target_elf_flavour)
3509 : (bfd_is_abs_section (h->root.u.def.section)
3510 && (h->elf_link_hash_flags
3511 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3512 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3513 }
3514
3515 /* If this is a final link, and the symbol was defined as a common
3516 symbol in a regular object file, and there was no definition in
3517 any dynamic object, then the linker will have allocated space for
3518 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3519 flag will not have been set. */
3520 if (h->root.type == bfd_link_hash_defined
3521 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3522 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3523 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3524 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3525 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3526
3527 /* If -Bsymbolic was used (which means to bind references to global
3528 symbols to the definition within the shared object), and this
3529 symbol was defined in a regular object, then it actually doesn't
3530 need a PLT entry, and we can accomplish that by forcing it local.
3531 Likewise, if the symbol has hidden or internal visibility.
3532 FIXME: It might be that we also do not need a PLT for other
3533 non-hidden visibilities, but we would have to tell that to the
3534 backend specifically; we can't just clear PLT-related data here. */
3535 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3536 && eif->info->shared
3537 && (eif->info->symbolic
3538 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3539 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3540 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3541 {
3542 struct elf_backend_data *bed;
3543 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
3544 if (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3545 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3546 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3547 (*bed->elf_backend_hide_symbol) (eif->info, h);
3548 }
3549
3550 /* If this is a weak defined symbol in a dynamic object, and we know
3551 the real definition in the dynamic object, copy interesting flags
3552 over to the real definition. */
3553 if (h->weakdef != NULL)
3554 {
3555 struct elf_link_hash_entry *weakdef;
3556
3557 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3558 || h->root.type == bfd_link_hash_defweak);
3559 weakdef = h->weakdef;
3560 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3561 || weakdef->root.type == bfd_link_hash_defweak);
3562 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3563
3564 /* If the real definition is defined by a regular object file,
3565 don't do anything special. See the longer description in
3566 elf_adjust_dynamic_symbol, below. */
3567 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3568 h->weakdef = NULL;
3569 else
3570 weakdef->elf_link_hash_flags |=
3571 (h->elf_link_hash_flags
3572 & (ELF_LINK_HASH_REF_REGULAR
3573 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3574 | ELF_LINK_NON_GOT_REF));
3575 }
3576
3577 return true;
3578 }
3579
3580 /* Make the backend pick a good value for a dynamic symbol. This is
3581 called via elf_link_hash_traverse, and also calls itself
3582 recursively. */
3583
3584 static boolean
3585 elf_adjust_dynamic_symbol (h, data)
3586 struct elf_link_hash_entry *h;
3587 PTR data;
3588 {
3589 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3590 bfd *dynobj;
3591 struct elf_backend_data *bed;
3592
3593 /* Ignore indirect symbols. These are added by the versioning code. */
3594 if (h->root.type == bfd_link_hash_indirect)
3595 return true;
3596
3597 /* Fix the symbol flags. */
3598 if (! elf_fix_symbol_flags (h, eif))
3599 return false;
3600
3601 /* If this symbol does not require a PLT entry, and it is not
3602 defined by a dynamic object, or is not referenced by a regular
3603 object, ignore it. We do have to handle a weak defined symbol,
3604 even if no regular object refers to it, if we decided to add it
3605 to the dynamic symbol table. FIXME: Do we normally need to worry
3606 about symbols which are defined by one dynamic object and
3607 referenced by another one? */
3608 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3609 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3610 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3611 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3612 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3613 {
3614 h->plt.offset = (bfd_vma) -1;
3615 return true;
3616 }
3617
3618 /* If we've already adjusted this symbol, don't do it again. This
3619 can happen via a recursive call. */
3620 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3621 return true;
3622
3623 /* Don't look at this symbol again. Note that we must set this
3624 after checking the above conditions, because we may look at a
3625 symbol once, decide not to do anything, and then get called
3626 recursively later after REF_REGULAR is set below. */
3627 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3628
3629 /* If this is a weak definition, and we know a real definition, and
3630 the real symbol is not itself defined by a regular object file,
3631 then get a good value for the real definition. We handle the
3632 real symbol first, for the convenience of the backend routine.
3633
3634 Note that there is a confusing case here. If the real definition
3635 is defined by a regular object file, we don't get the real symbol
3636 from the dynamic object, but we do get the weak symbol. If the
3637 processor backend uses a COPY reloc, then if some routine in the
3638 dynamic object changes the real symbol, we will not see that
3639 change in the corresponding weak symbol. This is the way other
3640 ELF linkers work as well, and seems to be a result of the shared
3641 library model.
3642
3643 I will clarify this issue. Most SVR4 shared libraries define the
3644 variable _timezone and define timezone as a weak synonym. The
3645 tzset call changes _timezone. If you write
3646 extern int timezone;
3647 int _timezone = 5;
3648 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3649 you might expect that, since timezone is a synonym for _timezone,
3650 the same number will print both times. However, if the processor
3651 backend uses a COPY reloc, then actually timezone will be copied
3652 into your process image, and, since you define _timezone
3653 yourself, _timezone will not. Thus timezone and _timezone will
3654 wind up at different memory locations. The tzset call will set
3655 _timezone, leaving timezone unchanged. */
3656
3657 if (h->weakdef != NULL)
3658 {
3659 /* If we get to this point, we know there is an implicit
3660 reference by a regular object file via the weak symbol H.
3661 FIXME: Is this really true? What if the traversal finds
3662 H->WEAKDEF before it finds H? */
3663 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3664
3665 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3666 return false;
3667 }
3668
3669 /* If a symbol has no type and no size and does not require a PLT
3670 entry, then we are probably about to do the wrong thing here: we
3671 are probably going to create a COPY reloc for an empty object.
3672 This case can arise when a shared object is built with assembly
3673 code, and the assembly code fails to set the symbol type. */
3674 if (h->size == 0
3675 && h->type == STT_NOTYPE
3676 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3677 (*_bfd_error_handler)
3678 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3679 h->root.root.string);
3680
3681 dynobj = elf_hash_table (eif->info)->dynobj;
3682 bed = get_elf_backend_data (dynobj);
3683 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3684 {
3685 eif->failed = true;
3686 return false;
3687 }
3688
3689 return true;
3690 }
3691 \f
3692 /* This routine is used to export all defined symbols into the dynamic
3693 symbol table. It is called via elf_link_hash_traverse. */
3694
3695 static boolean
3696 elf_export_symbol (h, data)
3697 struct elf_link_hash_entry *h;
3698 PTR data;
3699 {
3700 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3701
3702 /* Ignore indirect symbols. These are added by the versioning code. */
3703 if (h->root.type == bfd_link_hash_indirect)
3704 return true;
3705
3706 if (h->dynindx == -1
3707 && (h->elf_link_hash_flags
3708 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3709 {
3710 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3711 {
3712 eif->failed = true;
3713 return false;
3714 }
3715 }
3716
3717 return true;
3718 }
3719 \f
3720 /* Look through the symbols which are defined in other shared
3721 libraries and referenced here. Update the list of version
3722 dependencies. This will be put into the .gnu.version_r section.
3723 This function is called via elf_link_hash_traverse. */
3724
3725 static boolean
3726 elf_link_find_version_dependencies (h, data)
3727 struct elf_link_hash_entry *h;
3728 PTR data;
3729 {
3730 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3731 Elf_Internal_Verneed *t;
3732 Elf_Internal_Vernaux *a;
3733
3734 /* We only care about symbols defined in shared objects with version
3735 information. */
3736 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3737 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3738 || h->dynindx == -1
3739 || h->verinfo.verdef == NULL)
3740 return true;
3741
3742 /* See if we already know about this version. */
3743 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3744 {
3745 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3746 continue;
3747
3748 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3749 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3750 return true;
3751
3752 break;
3753 }
3754
3755 /* This is a new version. Add it to tree we are building. */
3756
3757 if (t == NULL)
3758 {
3759 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3760 if (t == NULL)
3761 {
3762 rinfo->failed = true;
3763 return false;
3764 }
3765
3766 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3767 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3768 elf_tdata (rinfo->output_bfd)->verref = t;
3769 }
3770
3771 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3772
3773 /* Note that we are copying a string pointer here, and testing it
3774 above. If bfd_elf_string_from_elf_section is ever changed to
3775 discard the string data when low in memory, this will have to be
3776 fixed. */
3777 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3778
3779 a->vna_flags = h->verinfo.verdef->vd_flags;
3780 a->vna_nextptr = t->vn_auxptr;
3781
3782 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3783 ++rinfo->vers;
3784
3785 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3786
3787 t->vn_auxptr = a;
3788
3789 return true;
3790 }
3791
3792 /* Figure out appropriate versions for all the symbols. We may not
3793 have the version number script until we have read all of the input
3794 files, so until that point we don't know which symbols should be
3795 local. This function is called via elf_link_hash_traverse. */
3796
3797 static boolean
3798 elf_link_assign_sym_version (h, data)
3799 struct elf_link_hash_entry *h;
3800 PTR data;
3801 {
3802 struct elf_assign_sym_version_info *sinfo =
3803 (struct elf_assign_sym_version_info *) data;
3804 struct bfd_link_info *info = sinfo->info;
3805 struct elf_backend_data *bed;
3806 struct elf_info_failed eif;
3807 char *p;
3808
3809 /* Fix the symbol flags. */
3810 eif.failed = false;
3811 eif.info = info;
3812 if (! elf_fix_symbol_flags (h, &eif))
3813 {
3814 if (eif.failed)
3815 sinfo->failed = true;
3816 return false;
3817 }
3818
3819 /* We only need version numbers for symbols defined in regular
3820 objects. */
3821 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3822 return true;
3823
3824 bed = get_elf_backend_data (sinfo->output_bfd);
3825 p = strchr (h->root.root.string, ELF_VER_CHR);
3826 if (p != NULL && h->verinfo.vertree == NULL)
3827 {
3828 struct bfd_elf_version_tree *t;
3829 boolean hidden;
3830
3831 hidden = true;
3832
3833 /* There are two consecutive ELF_VER_CHR characters if this is
3834 not a hidden symbol. */
3835 ++p;
3836 if (*p == ELF_VER_CHR)
3837 {
3838 hidden = false;
3839 ++p;
3840 }
3841
3842 /* If there is no version string, we can just return out. */
3843 if (*p == '\0')
3844 {
3845 if (hidden)
3846 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3847 return true;
3848 }
3849
3850 /* Look for the version. If we find it, it is no longer weak. */
3851 for (t = sinfo->verdefs; t != NULL; t = t->next)
3852 {
3853 if (strcmp (t->name, p) == 0)
3854 {
3855 int len;
3856 char *alc;
3857 struct bfd_elf_version_expr *d;
3858
3859 len = p - h->root.root.string;
3860 alc = bfd_alloc (sinfo->output_bfd, len);
3861 if (alc == NULL)
3862 return false;
3863 strncpy (alc, h->root.root.string, len - 1);
3864 alc[len - 1] = '\0';
3865 if (alc[len - 2] == ELF_VER_CHR)
3866 alc[len - 2] = '\0';
3867
3868 h->verinfo.vertree = t;
3869 t->used = true;
3870 d = NULL;
3871
3872 if (t->globals != NULL)
3873 {
3874 for (d = t->globals; d != NULL; d = d->next)
3875 if ((*d->match) (d, alc))
3876 break;
3877 }
3878
3879 /* See if there is anything to force this symbol to
3880 local scope. */
3881 if (d == NULL && t->locals != NULL)
3882 {
3883 for (d = t->locals; d != NULL; d = d->next)
3884 {
3885 if ((*d->match) (d, alc))
3886 {
3887 if (h->dynindx != -1
3888 && info->shared
3889 && ! sinfo->export_dynamic)
3890 {
3891 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3892 (*bed->elf_backend_hide_symbol) (info, h);
3893 /* FIXME: The name of the symbol has
3894 already been recorded in the dynamic
3895 string table section. */
3896 }
3897
3898 break;
3899 }
3900 }
3901 }
3902
3903 bfd_release (sinfo->output_bfd, alc);
3904 break;
3905 }
3906 }
3907
3908 /* If we are building an application, we need to create a
3909 version node for this version. */
3910 if (t == NULL && ! info->shared)
3911 {
3912 struct bfd_elf_version_tree **pp;
3913 int version_index;
3914
3915 /* If we aren't going to export this symbol, we don't need
3916 to worry about it. */
3917 if (h->dynindx == -1)
3918 return true;
3919
3920 t = ((struct bfd_elf_version_tree *)
3921 bfd_alloc (sinfo->output_bfd, sizeof *t));
3922 if (t == NULL)
3923 {
3924 sinfo->failed = true;
3925 return false;
3926 }
3927
3928 t->next = NULL;
3929 t->name = p;
3930 t->globals = NULL;
3931 t->locals = NULL;
3932 t->deps = NULL;
3933 t->name_indx = (unsigned int) -1;
3934 t->used = true;
3935
3936 version_index = 1;
3937 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3938 ++version_index;
3939 t->vernum = version_index;
3940
3941 *pp = t;
3942
3943 h->verinfo.vertree = t;
3944 }
3945 else if (t == NULL)
3946 {
3947 /* We could not find the version for a symbol when
3948 generating a shared archive. Return an error. */
3949 (*_bfd_error_handler)
3950 (_("%s: undefined versioned symbol name %s"),
3951 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3952 bfd_set_error (bfd_error_bad_value);
3953 sinfo->failed = true;
3954 return false;
3955 }
3956
3957 if (hidden)
3958 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3959 }
3960
3961 /* If we don't have a version for this symbol, see if we can find
3962 something. */
3963 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3964 {
3965 struct bfd_elf_version_tree *t;
3966 struct bfd_elf_version_tree *deflt;
3967 struct bfd_elf_version_expr *d;
3968
3969 /* See if can find what version this symbol is in. If the
3970 symbol is supposed to be local, then don't actually register
3971 it. */
3972 deflt = NULL;
3973 for (t = sinfo->verdefs; t != NULL; t = t->next)
3974 {
3975 if (t->globals != NULL)
3976 {
3977 for (d = t->globals; d != NULL; d = d->next)
3978 {
3979 if ((*d->match) (d, h->root.root.string))
3980 {
3981 h->verinfo.vertree = t;
3982 break;
3983 }
3984 }
3985
3986 if (d != NULL)
3987 break;
3988 }
3989
3990 if (t->locals != NULL)
3991 {
3992 for (d = t->locals; d != NULL; d = d->next)
3993 {
3994 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3995 deflt = t;
3996 else if ((*d->match) (d, h->root.root.string))
3997 {
3998 h->verinfo.vertree = t;
3999 if (h->dynindx != -1
4000 && info->shared
4001 && ! sinfo->export_dynamic)
4002 {
4003 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4004 (*bed->elf_backend_hide_symbol) (info, h);
4005 /* FIXME: The name of the symbol has already
4006 been recorded in the dynamic string table
4007 section. */
4008 }
4009 break;
4010 }
4011 }
4012
4013 if (d != NULL)
4014 break;
4015 }
4016 }
4017
4018 if (deflt != NULL && h->verinfo.vertree == NULL)
4019 {
4020 h->verinfo.vertree = deflt;
4021 if (h->dynindx != -1
4022 && info->shared
4023 && ! sinfo->export_dynamic)
4024 {
4025 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4026 (*bed->elf_backend_hide_symbol) (info, h);
4027 /* FIXME: The name of the symbol has already been
4028 recorded in the dynamic string table section. */
4029 }
4030 }
4031 }
4032
4033 return true;
4034 }
4035 \f
4036 /* Final phase of ELF linker. */
4037
4038 /* A structure we use to avoid passing large numbers of arguments. */
4039
4040 struct elf_final_link_info
4041 {
4042 /* General link information. */
4043 struct bfd_link_info *info;
4044 /* Output BFD. */
4045 bfd *output_bfd;
4046 /* Symbol string table. */
4047 struct bfd_strtab_hash *symstrtab;
4048 /* .dynsym section. */
4049 asection *dynsym_sec;
4050 /* .hash section. */
4051 asection *hash_sec;
4052 /* symbol version section (.gnu.version). */
4053 asection *symver_sec;
4054 /* Buffer large enough to hold contents of any section. */
4055 bfd_byte *contents;
4056 /* Buffer large enough to hold external relocs of any section. */
4057 PTR external_relocs;
4058 /* Buffer large enough to hold internal relocs of any section. */
4059 Elf_Internal_Rela *internal_relocs;
4060 /* Buffer large enough to hold external local symbols of any input
4061 BFD. */
4062 Elf_External_Sym *external_syms;
4063 /* Buffer large enough to hold internal local symbols of any input
4064 BFD. */
4065 Elf_Internal_Sym *internal_syms;
4066 /* Array large enough to hold a symbol index for each local symbol
4067 of any input BFD. */
4068 long *indices;
4069 /* Array large enough to hold a section pointer for each local
4070 symbol of any input BFD. */
4071 asection **sections;
4072 /* Buffer to hold swapped out symbols. */
4073 Elf_External_Sym *symbuf;
4074 /* Number of swapped out symbols in buffer. */
4075 size_t symbuf_count;
4076 /* Number of symbols which fit in symbuf. */
4077 size_t symbuf_size;
4078 };
4079
4080 static boolean elf_link_output_sym
4081 PARAMS ((struct elf_final_link_info *, const char *,
4082 Elf_Internal_Sym *, asection *));
4083 static boolean elf_link_flush_output_syms
4084 PARAMS ((struct elf_final_link_info *));
4085 static boolean elf_link_output_extsym
4086 PARAMS ((struct elf_link_hash_entry *, PTR));
4087 static boolean elf_link_sec_merge_syms
4088 PARAMS ((struct elf_link_hash_entry *, PTR));
4089 static boolean elf_link_input_bfd
4090 PARAMS ((struct elf_final_link_info *, bfd *));
4091 static boolean elf_reloc_link_order
4092 PARAMS ((bfd *, struct bfd_link_info *, asection *,
4093 struct bfd_link_order *));
4094
4095 /* This struct is used to pass information to elf_link_output_extsym. */
4096
4097 struct elf_outext_info
4098 {
4099 boolean failed;
4100 boolean localsyms;
4101 struct elf_final_link_info *finfo;
4102 };
4103
4104 /* Compute the size of, and allocate space for, REL_HDR which is the
4105 section header for a section containing relocations for O. */
4106
4107 static boolean
4108 elf_link_size_reloc_section (abfd, rel_hdr, o)
4109 bfd *abfd;
4110 Elf_Internal_Shdr *rel_hdr;
4111 asection *o;
4112 {
4113 register struct elf_link_hash_entry **p, **pend;
4114 unsigned reloc_count;
4115
4116 /* Figure out how many relocations there will be. */
4117 if (rel_hdr == &elf_section_data (o)->rel_hdr)
4118 reloc_count = elf_section_data (o)->rel_count;
4119 else
4120 reloc_count = elf_section_data (o)->rel_count2;
4121
4122 /* That allows us to calculate the size of the section. */
4123 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
4124
4125 /* The contents field must last into write_object_contents, so we
4126 allocate it with bfd_alloc rather than malloc. Also since we
4127 cannot be sure that the contents will actually be filled in,
4128 we zero the allocated space. */
4129 rel_hdr->contents = (PTR) bfd_zalloc (abfd, rel_hdr->sh_size);
4130 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
4131 return false;
4132
4133 /* We only allocate one set of hash entries, so we only do it the
4134 first time we are called. */
4135 if (elf_section_data (o)->rel_hashes == NULL)
4136 {
4137 p = ((struct elf_link_hash_entry **)
4138 bfd_malloc (o->reloc_count
4139 * sizeof (struct elf_link_hash_entry *)));
4140 if (p == NULL && o->reloc_count != 0)
4141 return false;
4142
4143 elf_section_data (o)->rel_hashes = p;
4144 pend = p + o->reloc_count;
4145 for (; p < pend; p++)
4146 *p = NULL;
4147 }
4148
4149 return true;
4150 }
4151
4152 /* When performing a relocateable link, the input relocations are
4153 preserved. But, if they reference global symbols, the indices
4154 referenced must be updated. Update all the relocations in
4155 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4156
4157 static void
4158 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4159 bfd *abfd;
4160 Elf_Internal_Shdr *rel_hdr;
4161 unsigned int count;
4162 struct elf_link_hash_entry **rel_hash;
4163 {
4164 unsigned int i;
4165 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4166
4167 for (i = 0; i < count; i++, rel_hash++)
4168 {
4169 if (*rel_hash == NULL)
4170 continue;
4171
4172 BFD_ASSERT ((*rel_hash)->indx >= 0);
4173
4174 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4175 {
4176 Elf_External_Rel *erel;
4177 Elf_Internal_Rel irel;
4178
4179 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4180 if (bed->s->swap_reloc_in)
4181 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, &irel);
4182 else
4183 elf_swap_reloc_in (abfd, erel, &irel);
4184 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
4185 ELF_R_TYPE (irel.r_info));
4186 if (bed->s->swap_reloc_out)
4187 (*bed->s->swap_reloc_out) (abfd, &irel, (bfd_byte *) erel);
4188 else
4189 elf_swap_reloc_out (abfd, &irel, erel);
4190 }
4191 else
4192 {
4193 Elf_External_Rela *erela;
4194 Elf_Internal_Rela irela;
4195
4196 BFD_ASSERT (rel_hdr->sh_entsize
4197 == sizeof (Elf_External_Rela));
4198
4199 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4200 if (bed->s->swap_reloca_in)
4201 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, &irela);
4202 else
4203 elf_swap_reloca_in (abfd, erela, &irela);
4204 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4205 ELF_R_TYPE (irela.r_info));
4206 if (bed->s->swap_reloca_out)
4207 (*bed->s->swap_reloca_out) (abfd, &irela, (bfd_byte *) erela);
4208 else
4209 elf_swap_reloca_out (abfd, &irela, erela);
4210 }
4211 }
4212 }
4213
4214 /* Do the final step of an ELF link. */
4215
4216 boolean
4217 elf_bfd_final_link (abfd, info)
4218 bfd *abfd;
4219 struct bfd_link_info *info;
4220 {
4221 boolean dynamic;
4222 bfd *dynobj;
4223 struct elf_final_link_info finfo;
4224 register asection *o;
4225 register struct bfd_link_order *p;
4226 register bfd *sub;
4227 size_t max_contents_size;
4228 size_t max_external_reloc_size;
4229 size_t max_internal_reloc_count;
4230 size_t max_sym_count;
4231 file_ptr off;
4232 Elf_Internal_Sym elfsym;
4233 unsigned int i;
4234 Elf_Internal_Shdr *symtab_hdr;
4235 Elf_Internal_Shdr *symstrtab_hdr;
4236 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4237 struct elf_outext_info eoinfo;
4238 boolean merged;
4239
4240 if (info->shared)
4241 abfd->flags |= DYNAMIC;
4242
4243 dynamic = elf_hash_table (info)->dynamic_sections_created;
4244 dynobj = elf_hash_table (info)->dynobj;
4245
4246 finfo.info = info;
4247 finfo.output_bfd = abfd;
4248 finfo.symstrtab = elf_stringtab_init ();
4249 if (finfo.symstrtab == NULL)
4250 return false;
4251
4252 if (! dynamic)
4253 {
4254 finfo.dynsym_sec = NULL;
4255 finfo.hash_sec = NULL;
4256 finfo.symver_sec = NULL;
4257 }
4258 else
4259 {
4260 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4261 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4262 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4263 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4264 /* Note that it is OK if symver_sec is NULL. */
4265 }
4266
4267 finfo.contents = NULL;
4268 finfo.external_relocs = NULL;
4269 finfo.internal_relocs = NULL;
4270 finfo.external_syms = NULL;
4271 finfo.internal_syms = NULL;
4272 finfo.indices = NULL;
4273 finfo.sections = NULL;
4274 finfo.symbuf = NULL;
4275 finfo.symbuf_count = 0;
4276
4277 /* Count up the number of relocations we will output for each output
4278 section, so that we know the sizes of the reloc sections. We
4279 also figure out some maximum sizes. */
4280 max_contents_size = 0;
4281 max_external_reloc_size = 0;
4282 max_internal_reloc_count = 0;
4283 max_sym_count = 0;
4284 merged = false;
4285 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4286 {
4287 o->reloc_count = 0;
4288
4289 for (p = o->link_order_head; p != NULL; p = p->next)
4290 {
4291 if (p->type == bfd_section_reloc_link_order
4292 || p->type == bfd_symbol_reloc_link_order)
4293 ++o->reloc_count;
4294 else if (p->type == bfd_indirect_link_order)
4295 {
4296 asection *sec;
4297
4298 sec = p->u.indirect.section;
4299
4300 /* Mark all sections which are to be included in the
4301 link. This will normally be every section. We need
4302 to do this so that we can identify any sections which
4303 the linker has decided to not include. */
4304 sec->linker_mark = true;
4305
4306 if (sec->flags & SEC_MERGE)
4307 merged = true;
4308
4309 if (info->relocateable || info->emitrelocations)
4310 o->reloc_count += sec->reloc_count;
4311
4312 if (sec->_raw_size > max_contents_size)
4313 max_contents_size = sec->_raw_size;
4314 if (sec->_cooked_size > max_contents_size)
4315 max_contents_size = sec->_cooked_size;
4316
4317 /* We are interested in just local symbols, not all
4318 symbols. */
4319 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4320 && (sec->owner->flags & DYNAMIC) == 0)
4321 {
4322 size_t sym_count;
4323
4324 if (elf_bad_symtab (sec->owner))
4325 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4326 / sizeof (Elf_External_Sym));
4327 else
4328 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4329
4330 if (sym_count > max_sym_count)
4331 max_sym_count = sym_count;
4332
4333 if ((sec->flags & SEC_RELOC) != 0)
4334 {
4335 size_t ext_size;
4336
4337 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4338 if (ext_size > max_external_reloc_size)
4339 max_external_reloc_size = ext_size;
4340 if (sec->reloc_count > max_internal_reloc_count)
4341 max_internal_reloc_count = sec->reloc_count;
4342 }
4343 }
4344 }
4345 }
4346
4347 if (o->reloc_count > 0)
4348 o->flags |= SEC_RELOC;
4349 else
4350 {
4351 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4352 set it (this is probably a bug) and if it is set
4353 assign_section_numbers will create a reloc section. */
4354 o->flags &=~ SEC_RELOC;
4355 }
4356
4357 /* If the SEC_ALLOC flag is not set, force the section VMA to
4358 zero. This is done in elf_fake_sections as well, but forcing
4359 the VMA to 0 here will ensure that relocs against these
4360 sections are handled correctly. */
4361 if ((o->flags & SEC_ALLOC) == 0
4362 && ! o->user_set_vma)
4363 o->vma = 0;
4364 }
4365
4366 if (! info->relocateable && merged)
4367 elf_link_hash_traverse (elf_hash_table (info),
4368 elf_link_sec_merge_syms, (PTR) abfd);
4369
4370 /* Figure out the file positions for everything but the symbol table
4371 and the relocs. We set symcount to force assign_section_numbers
4372 to create a symbol table. */
4373 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4374 BFD_ASSERT (! abfd->output_has_begun);
4375 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4376 goto error_return;
4377
4378 /* Figure out how many relocations we will have in each section.
4379 Just using RELOC_COUNT isn't good enough since that doesn't
4380 maintain a separate value for REL vs. RELA relocations. */
4381 if (info->relocateable || info->emitrelocations)
4382 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4383 for (o = sub->sections; o != NULL; o = o->next)
4384 {
4385 asection *output_section;
4386
4387 if (! o->linker_mark)
4388 {
4389 /* This section was omitted from the link. */
4390 continue;
4391 }
4392
4393 output_section = o->output_section;
4394
4395 if (output_section != NULL
4396 && (o->flags & SEC_RELOC) != 0)
4397 {
4398 struct bfd_elf_section_data *esdi
4399 = elf_section_data (o);
4400 struct bfd_elf_section_data *esdo
4401 = elf_section_data (output_section);
4402 unsigned int *rel_count;
4403 unsigned int *rel_count2;
4404
4405 /* We must be careful to add the relocation froms the
4406 input section to the right output count. */
4407 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4408 {
4409 rel_count = &esdo->rel_count;
4410 rel_count2 = &esdo->rel_count2;
4411 }
4412 else
4413 {
4414 rel_count = &esdo->rel_count2;
4415 rel_count2 = &esdo->rel_count;
4416 }
4417
4418 *rel_count += (esdi->rel_hdr.sh_size
4419 / esdi->rel_hdr.sh_entsize);
4420 if (esdi->rel_hdr2)
4421 *rel_count2 += (esdi->rel_hdr2->sh_size
4422 / esdi->rel_hdr2->sh_entsize);
4423 }
4424 }
4425
4426 /* That created the reloc sections. Set their sizes, and assign
4427 them file positions, and allocate some buffers. */
4428 for (o = abfd->sections; o != NULL; o = o->next)
4429 {
4430 if ((o->flags & SEC_RELOC) != 0)
4431 {
4432 if (!elf_link_size_reloc_section (abfd,
4433 &elf_section_data (o)->rel_hdr,
4434 o))
4435 goto error_return;
4436
4437 if (elf_section_data (o)->rel_hdr2
4438 && !elf_link_size_reloc_section (abfd,
4439 elf_section_data (o)->rel_hdr2,
4440 o))
4441 goto error_return;
4442 }
4443
4444 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4445 to count upwards while actually outputting the relocations. */
4446 elf_section_data (o)->rel_count = 0;
4447 elf_section_data (o)->rel_count2 = 0;
4448 }
4449
4450 _bfd_elf_assign_file_positions_for_relocs (abfd);
4451
4452 /* We have now assigned file positions for all the sections except
4453 .symtab and .strtab. We start the .symtab section at the current
4454 file position, and write directly to it. We build the .strtab
4455 section in memory. */
4456 bfd_get_symcount (abfd) = 0;
4457 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4458 /* sh_name is set in prep_headers. */
4459 symtab_hdr->sh_type = SHT_SYMTAB;
4460 symtab_hdr->sh_flags = 0;
4461 symtab_hdr->sh_addr = 0;
4462 symtab_hdr->sh_size = 0;
4463 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4464 /* sh_link is set in assign_section_numbers. */
4465 /* sh_info is set below. */
4466 /* sh_offset is set just below. */
4467 symtab_hdr->sh_addralign = bed->s->file_align;
4468
4469 off = elf_tdata (abfd)->next_file_pos;
4470 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4471
4472 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4473 incorrect. We do not yet know the size of the .symtab section.
4474 We correct next_file_pos below, after we do know the size. */
4475
4476 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4477 continuously seeking to the right position in the file. */
4478 if (! info->keep_memory || max_sym_count < 20)
4479 finfo.symbuf_size = 20;
4480 else
4481 finfo.symbuf_size = max_sym_count;
4482 finfo.symbuf = ((Elf_External_Sym *)
4483 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4484 if (finfo.symbuf == NULL)
4485 goto error_return;
4486
4487 /* Start writing out the symbol table. The first symbol is always a
4488 dummy symbol. */
4489 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4490 {
4491 elfsym.st_value = 0;
4492 elfsym.st_size = 0;
4493 elfsym.st_info = 0;
4494 elfsym.st_other = 0;
4495 elfsym.st_shndx = SHN_UNDEF;
4496 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4497 &elfsym, bfd_und_section_ptr))
4498 goto error_return;
4499 }
4500
4501 #if 0
4502 /* Some standard ELF linkers do this, but we don't because it causes
4503 bootstrap comparison failures. */
4504 /* Output a file symbol for the output file as the second symbol.
4505 We output this even if we are discarding local symbols, although
4506 I'm not sure if this is correct. */
4507 elfsym.st_value = 0;
4508 elfsym.st_size = 0;
4509 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4510 elfsym.st_other = 0;
4511 elfsym.st_shndx = SHN_ABS;
4512 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4513 &elfsym, bfd_abs_section_ptr))
4514 goto error_return;
4515 #endif
4516
4517 /* Output a symbol for each section. We output these even if we are
4518 discarding local symbols, since they are used for relocs. These
4519 symbols have no names. We store the index of each one in the
4520 index field of the section, so that we can find it again when
4521 outputting relocs. */
4522 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4523 {
4524 elfsym.st_size = 0;
4525 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4526 elfsym.st_other = 0;
4527 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4528 {
4529 o = section_from_elf_index (abfd, i);
4530 if (o != NULL)
4531 o->target_index = bfd_get_symcount (abfd);
4532 elfsym.st_shndx = i;
4533 if (info->relocateable || o == NULL)
4534 elfsym.st_value = 0;
4535 else
4536 elfsym.st_value = o->vma;
4537 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4538 &elfsym, o))
4539 goto error_return;
4540 }
4541 }
4542
4543 /* Allocate some memory to hold information read in from the input
4544 files. */
4545 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4546 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4547 finfo.internal_relocs = ((Elf_Internal_Rela *)
4548 bfd_malloc (max_internal_reloc_count
4549 * sizeof (Elf_Internal_Rela)
4550 * bed->s->int_rels_per_ext_rel));
4551 finfo.external_syms = ((Elf_External_Sym *)
4552 bfd_malloc (max_sym_count
4553 * sizeof (Elf_External_Sym)));
4554 finfo.internal_syms = ((Elf_Internal_Sym *)
4555 bfd_malloc (max_sym_count
4556 * sizeof (Elf_Internal_Sym)));
4557 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4558 finfo.sections = ((asection **)
4559 bfd_malloc (max_sym_count * sizeof (asection *)));
4560 if ((finfo.contents == NULL && max_contents_size != 0)
4561 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4562 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4563 || (finfo.external_syms == NULL && max_sym_count != 0)
4564 || (finfo.internal_syms == NULL && max_sym_count != 0)
4565 || (finfo.indices == NULL && max_sym_count != 0)
4566 || (finfo.sections == NULL && max_sym_count != 0))
4567 goto error_return;
4568
4569 /* Since ELF permits relocations to be against local symbols, we
4570 must have the local symbols available when we do the relocations.
4571 Since we would rather only read the local symbols once, and we
4572 would rather not keep them in memory, we handle all the
4573 relocations for a single input file at the same time.
4574
4575 Unfortunately, there is no way to know the total number of local
4576 symbols until we have seen all of them, and the local symbol
4577 indices precede the global symbol indices. This means that when
4578 we are generating relocateable output, and we see a reloc against
4579 a global symbol, we can not know the symbol index until we have
4580 finished examining all the local symbols to see which ones we are
4581 going to output. To deal with this, we keep the relocations in
4582 memory, and don't output them until the end of the link. This is
4583 an unfortunate waste of memory, but I don't see a good way around
4584 it. Fortunately, it only happens when performing a relocateable
4585 link, which is not the common case. FIXME: If keep_memory is set
4586 we could write the relocs out and then read them again; I don't
4587 know how bad the memory loss will be. */
4588
4589 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4590 sub->output_has_begun = false;
4591 for (o = abfd->sections; o != NULL; o = o->next)
4592 {
4593 for (p = o->link_order_head; p != NULL; p = p->next)
4594 {
4595 if (p->type == bfd_indirect_link_order
4596 && (bfd_get_flavour (p->u.indirect.section->owner)
4597 == bfd_target_elf_flavour))
4598 {
4599 sub = p->u.indirect.section->owner;
4600 if (! sub->output_has_begun)
4601 {
4602 if (! elf_link_input_bfd (&finfo, sub))
4603 goto error_return;
4604 sub->output_has_begun = true;
4605 }
4606 }
4607 else if (p->type == bfd_section_reloc_link_order
4608 || p->type == bfd_symbol_reloc_link_order)
4609 {
4610 if (! elf_reloc_link_order (abfd, info, o, p))
4611 goto error_return;
4612 }
4613 else
4614 {
4615 if (! _bfd_default_link_order (abfd, info, o, p))
4616 goto error_return;
4617 }
4618 }
4619 }
4620
4621 /* That wrote out all the local symbols. Finish up the symbol table
4622 with the global symbols. Even if we want to strip everything we
4623 can, we still need to deal with those global symbols that got
4624 converted to local in a version script. */
4625
4626 if (info->shared)
4627 {
4628 /* Output any global symbols that got converted to local in a
4629 version script. We do this in a separate step since ELF
4630 requires all local symbols to appear prior to any global
4631 symbols. FIXME: We should only do this if some global
4632 symbols were, in fact, converted to become local. FIXME:
4633 Will this work correctly with the Irix 5 linker? */
4634 eoinfo.failed = false;
4635 eoinfo.finfo = &finfo;
4636 eoinfo.localsyms = true;
4637 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4638 (PTR) &eoinfo);
4639 if (eoinfo.failed)
4640 return false;
4641 }
4642
4643 /* The sh_info field records the index of the first non local symbol. */
4644 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4645
4646 if (dynamic
4647 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
4648 {
4649 Elf_Internal_Sym sym;
4650 Elf_External_Sym *dynsym =
4651 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4652 long last_local = 0;
4653
4654 /* Write out the section symbols for the output sections. */
4655 if (info->shared)
4656 {
4657 asection *s;
4658
4659 sym.st_size = 0;
4660 sym.st_name = 0;
4661 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4662 sym.st_other = 0;
4663
4664 for (s = abfd->sections; s != NULL; s = s->next)
4665 {
4666 int indx;
4667 indx = elf_section_data (s)->this_idx;
4668 BFD_ASSERT (indx > 0);
4669 sym.st_shndx = indx;
4670 sym.st_value = s->vma;
4671
4672 elf_swap_symbol_out (abfd, &sym,
4673 dynsym + elf_section_data (s)->dynindx);
4674 }
4675
4676 last_local = bfd_count_sections (abfd);
4677 }
4678
4679 /* Write out the local dynsyms. */
4680 if (elf_hash_table (info)->dynlocal)
4681 {
4682 struct elf_link_local_dynamic_entry *e;
4683 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4684 {
4685 asection *s;
4686
4687 sym.st_size = e->isym.st_size;
4688 sym.st_other = e->isym.st_other;
4689
4690 /* Copy the internal symbol as is.
4691 Note that we saved a word of storage and overwrote
4692 the original st_name with the dynstr_index. */
4693 sym = e->isym;
4694
4695 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4696 {
4697 s = bfd_section_from_elf_index (e->input_bfd,
4698 e->isym.st_shndx);
4699
4700 sym.st_shndx =
4701 elf_section_data (s->output_section)->this_idx;
4702 sym.st_value = (s->output_section->vma
4703 + s->output_offset
4704 + e->isym.st_value);
4705 }
4706
4707 if (last_local < e->dynindx)
4708 last_local = e->dynindx;
4709
4710 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4711 }
4712 }
4713
4714 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4715 last_local + 1;
4716 }
4717
4718 /* We get the global symbols from the hash table. */
4719 eoinfo.failed = false;
4720 eoinfo.localsyms = false;
4721 eoinfo.finfo = &finfo;
4722 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4723 (PTR) &eoinfo);
4724 if (eoinfo.failed)
4725 return false;
4726
4727 /* If backend needs to output some symbols not present in the hash
4728 table, do it now. */
4729 if (bed->elf_backend_output_arch_syms)
4730 {
4731 if (! (*bed->elf_backend_output_arch_syms)
4732 (abfd, info, (PTR) &finfo,
4733 (boolean (*) PARAMS ((PTR, const char *,
4734 Elf_Internal_Sym *, asection *)))
4735 elf_link_output_sym))
4736 return false;
4737 }
4738
4739 /* Flush all symbols to the file. */
4740 if (! elf_link_flush_output_syms (&finfo))
4741 return false;
4742
4743 /* Now we know the size of the symtab section. */
4744 off += symtab_hdr->sh_size;
4745
4746 /* Finish up and write out the symbol string table (.strtab)
4747 section. */
4748 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4749 /* sh_name was set in prep_headers. */
4750 symstrtab_hdr->sh_type = SHT_STRTAB;
4751 symstrtab_hdr->sh_flags = 0;
4752 symstrtab_hdr->sh_addr = 0;
4753 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4754 symstrtab_hdr->sh_entsize = 0;
4755 symstrtab_hdr->sh_link = 0;
4756 symstrtab_hdr->sh_info = 0;
4757 /* sh_offset is set just below. */
4758 symstrtab_hdr->sh_addralign = 1;
4759
4760 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4761 elf_tdata (abfd)->next_file_pos = off;
4762
4763 if (bfd_get_symcount (abfd) > 0)
4764 {
4765 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4766 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4767 return false;
4768 }
4769
4770 /* Adjust the relocs to have the correct symbol indices. */
4771 for (o = abfd->sections; o != NULL; o = o->next)
4772 {
4773 if ((o->flags & SEC_RELOC) == 0)
4774 continue;
4775
4776 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4777 elf_section_data (o)->rel_count,
4778 elf_section_data (o)->rel_hashes);
4779 if (elf_section_data (o)->rel_hdr2 != NULL)
4780 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4781 elf_section_data (o)->rel_count2,
4782 (elf_section_data (o)->rel_hashes
4783 + elf_section_data (o)->rel_count));
4784
4785 /* Set the reloc_count field to 0 to prevent write_relocs from
4786 trying to swap the relocs out itself. */
4787 o->reloc_count = 0;
4788 }
4789
4790 /* If we are linking against a dynamic object, or generating a
4791 shared library, finish up the dynamic linking information. */
4792 if (dynamic)
4793 {
4794 Elf_External_Dyn *dyncon, *dynconend;
4795
4796 /* Fix up .dynamic entries. */
4797 o = bfd_get_section_by_name (dynobj, ".dynamic");
4798 BFD_ASSERT (o != NULL);
4799
4800 dyncon = (Elf_External_Dyn *) o->contents;
4801 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4802 for (; dyncon < dynconend; dyncon++)
4803 {
4804 Elf_Internal_Dyn dyn;
4805 const char *name;
4806 unsigned int type;
4807
4808 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4809
4810 switch (dyn.d_tag)
4811 {
4812 default:
4813 break;
4814 case DT_INIT:
4815 name = info->init_function;
4816 goto get_sym;
4817 case DT_FINI:
4818 name = info->fini_function;
4819 get_sym:
4820 {
4821 struct elf_link_hash_entry *h;
4822
4823 h = elf_link_hash_lookup (elf_hash_table (info), name,
4824 false, false, true);
4825 if (h != NULL
4826 && (h->root.type == bfd_link_hash_defined
4827 || h->root.type == bfd_link_hash_defweak))
4828 {
4829 dyn.d_un.d_val = h->root.u.def.value;
4830 o = h->root.u.def.section;
4831 if (o->output_section != NULL)
4832 dyn.d_un.d_val += (o->output_section->vma
4833 + o->output_offset);
4834 else
4835 {
4836 /* The symbol is imported from another shared
4837 library and does not apply to this one. */
4838 dyn.d_un.d_val = 0;
4839 }
4840
4841 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4842 }
4843 }
4844 break;
4845
4846 case DT_HASH:
4847 name = ".hash";
4848 goto get_vma;
4849 case DT_STRTAB:
4850 name = ".dynstr";
4851 goto get_vma;
4852 case DT_SYMTAB:
4853 name = ".dynsym";
4854 goto get_vma;
4855 case DT_VERDEF:
4856 name = ".gnu.version_d";
4857 goto get_vma;
4858 case DT_VERNEED:
4859 name = ".gnu.version_r";
4860 goto get_vma;
4861 case DT_VERSYM:
4862 name = ".gnu.version";
4863 get_vma:
4864 o = bfd_get_section_by_name (abfd, name);
4865 BFD_ASSERT (o != NULL);
4866 dyn.d_un.d_ptr = o->vma;
4867 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4868 break;
4869
4870 case DT_REL:
4871 case DT_RELA:
4872 case DT_RELSZ:
4873 case DT_RELASZ:
4874 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4875 type = SHT_REL;
4876 else
4877 type = SHT_RELA;
4878 dyn.d_un.d_val = 0;
4879 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4880 {
4881 Elf_Internal_Shdr *hdr;
4882
4883 hdr = elf_elfsections (abfd)[i];
4884 if (hdr->sh_type == type
4885 && (hdr->sh_flags & SHF_ALLOC) != 0)
4886 {
4887 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4888 dyn.d_un.d_val += hdr->sh_size;
4889 else
4890 {
4891 if (dyn.d_un.d_val == 0
4892 || hdr->sh_addr < dyn.d_un.d_val)
4893 dyn.d_un.d_val = hdr->sh_addr;
4894 }
4895 }
4896 }
4897 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4898 break;
4899 }
4900 }
4901 }
4902
4903 /* If we have created any dynamic sections, then output them. */
4904 if (dynobj != NULL)
4905 {
4906 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4907 goto error_return;
4908
4909 for (o = dynobj->sections; o != NULL; o = o->next)
4910 {
4911 if ((o->flags & SEC_HAS_CONTENTS) == 0
4912 || o->_raw_size == 0
4913 || o->output_section == bfd_abs_section_ptr)
4914 continue;
4915 if ((o->flags & SEC_LINKER_CREATED) == 0)
4916 {
4917 /* At this point, we are only interested in sections
4918 created by elf_link_create_dynamic_sections. */
4919 continue;
4920 }
4921 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4922 != SHT_STRTAB)
4923 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4924 {
4925 if (! bfd_set_section_contents (abfd, o->output_section,
4926 o->contents, o->output_offset,
4927 o->_raw_size))
4928 goto error_return;
4929 }
4930 else
4931 {
4932 file_ptr off;
4933
4934 /* The contents of the .dynstr section are actually in a
4935 stringtab. */
4936 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4937 if (bfd_seek (abfd, off, SEEK_SET) != 0
4938 || ! _bfd_stringtab_emit (abfd,
4939 elf_hash_table (info)->dynstr))
4940 goto error_return;
4941 }
4942 }
4943 }
4944
4945 /* If we have optimized stabs strings, output them. */
4946 if (elf_hash_table (info)->stab_info != NULL)
4947 {
4948 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4949 goto error_return;
4950 }
4951
4952 if (finfo.symstrtab != NULL)
4953 _bfd_stringtab_free (finfo.symstrtab);
4954 if (finfo.contents != NULL)
4955 free (finfo.contents);
4956 if (finfo.external_relocs != NULL)
4957 free (finfo.external_relocs);
4958 if (finfo.internal_relocs != NULL)
4959 free (finfo.internal_relocs);
4960 if (finfo.external_syms != NULL)
4961 free (finfo.external_syms);
4962 if (finfo.internal_syms != NULL)
4963 free (finfo.internal_syms);
4964 if (finfo.indices != NULL)
4965 free (finfo.indices);
4966 if (finfo.sections != NULL)
4967 free (finfo.sections);
4968 if (finfo.symbuf != NULL)
4969 free (finfo.symbuf);
4970 for (o = abfd->sections; o != NULL; o = o->next)
4971 {
4972 if ((o->flags & SEC_RELOC) != 0
4973 && elf_section_data (o)->rel_hashes != NULL)
4974 free (elf_section_data (o)->rel_hashes);
4975 }
4976
4977 elf_tdata (abfd)->linker = true;
4978
4979 return true;
4980
4981 error_return:
4982 if (finfo.symstrtab != NULL)
4983 _bfd_stringtab_free (finfo.symstrtab);
4984 if (finfo.contents != NULL)
4985 free (finfo.contents);
4986 if (finfo.external_relocs != NULL)
4987 free (finfo.external_relocs);
4988 if (finfo.internal_relocs != NULL)
4989 free (finfo.internal_relocs);
4990 if (finfo.external_syms != NULL)
4991 free (finfo.external_syms);
4992 if (finfo.internal_syms != NULL)
4993 free (finfo.internal_syms);
4994 if (finfo.indices != NULL)
4995 free (finfo.indices);
4996 if (finfo.sections != NULL)
4997 free (finfo.sections);
4998 if (finfo.symbuf != NULL)
4999 free (finfo.symbuf);
5000 for (o = abfd->sections; o != NULL; o = o->next)
5001 {
5002 if ((o->flags & SEC_RELOC) != 0
5003 && elf_section_data (o)->rel_hashes != NULL)
5004 free (elf_section_data (o)->rel_hashes);
5005 }
5006
5007 return false;
5008 }
5009
5010 /* Add a symbol to the output symbol table. */
5011
5012 static boolean
5013 elf_link_output_sym (finfo, name, elfsym, input_sec)
5014 struct elf_final_link_info *finfo;
5015 const char *name;
5016 Elf_Internal_Sym *elfsym;
5017 asection *input_sec;
5018 {
5019 boolean (*output_symbol_hook) PARAMS ((bfd *,
5020 struct bfd_link_info *info,
5021 const char *,
5022 Elf_Internal_Sym *,
5023 asection *));
5024
5025 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
5026 elf_backend_link_output_symbol_hook;
5027 if (output_symbol_hook != NULL)
5028 {
5029 if (! ((*output_symbol_hook)
5030 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
5031 return false;
5032 }
5033
5034 if (name == (const char *) NULL || *name == '\0')
5035 elfsym->st_name = 0;
5036 else if (input_sec->flags & SEC_EXCLUDE)
5037 elfsym->st_name = 0;
5038 else
5039 {
5040 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5041 name, true,
5042 false);
5043 if (elfsym->st_name == (unsigned long) -1)
5044 return false;
5045 }
5046
5047 if (finfo->symbuf_count >= finfo->symbuf_size)
5048 {
5049 if (! elf_link_flush_output_syms (finfo))
5050 return false;
5051 }
5052
5053 elf_swap_symbol_out (finfo->output_bfd, elfsym,
5054 (PTR) (finfo->symbuf + finfo->symbuf_count));
5055 ++finfo->symbuf_count;
5056
5057 ++ bfd_get_symcount (finfo->output_bfd);
5058
5059 return true;
5060 }
5061
5062 /* Flush the output symbols to the file. */
5063
5064 static boolean
5065 elf_link_flush_output_syms (finfo)
5066 struct elf_final_link_info *finfo;
5067 {
5068 if (finfo->symbuf_count > 0)
5069 {
5070 Elf_Internal_Shdr *symtab;
5071
5072 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5073
5074 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
5075 SEEK_SET) != 0
5076 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
5077 sizeof (Elf_External_Sym), finfo->output_bfd)
5078 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
5079 return false;
5080
5081 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
5082
5083 finfo->symbuf_count = 0;
5084 }
5085
5086 return true;
5087 }
5088
5089 /* Adjust all external symbols pointing into SEC_MERGE sections
5090 to reflect the object merging within the sections. */
5091
5092 static boolean
5093 elf_link_sec_merge_syms (h, data)
5094 struct elf_link_hash_entry *h;
5095 PTR data;
5096 {
5097 asection *sec;
5098
5099 if ((h->root.type == bfd_link_hash_defined
5100 || h->root.type == bfd_link_hash_defweak)
5101 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
5102 && elf_section_data (sec)->merge_info)
5103 {
5104 bfd *output_bfd = (bfd *) data;
5105
5106 h->root.u.def.value =
5107 _bfd_merged_section_offset (output_bfd,
5108 &h->root.u.def.section,
5109 elf_section_data (sec)->merge_info,
5110 h->root.u.def.value, (bfd_vma) 0);
5111 }
5112
5113 return true;
5114 }
5115
5116 /* Add an external symbol to the symbol table. This is called from
5117 the hash table traversal routine. When generating a shared object,
5118 we go through the symbol table twice. The first time we output
5119 anything that might have been forced to local scope in a version
5120 script. The second time we output the symbols that are still
5121 global symbols. */
5122
5123 static boolean
5124 elf_link_output_extsym (h, data)
5125 struct elf_link_hash_entry *h;
5126 PTR data;
5127 {
5128 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
5129 struct elf_final_link_info *finfo = eoinfo->finfo;
5130 boolean strip;
5131 Elf_Internal_Sym sym;
5132 asection *input_sec;
5133
5134 /* Decide whether to output this symbol in this pass. */
5135 if (eoinfo->localsyms)
5136 {
5137 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5138 return true;
5139 }
5140 else
5141 {
5142 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5143 return true;
5144 }
5145
5146 /* If we are not creating a shared library, and this symbol is
5147 referenced by a shared library but is not defined anywhere, then
5148 warn that it is undefined. If we do not do this, the runtime
5149 linker will complain that the symbol is undefined when the
5150 program is run. We don't have to worry about symbols that are
5151 referenced by regular files, because we will already have issued
5152 warnings for them. */
5153 if (! finfo->info->relocateable
5154 && ! finfo->info->allow_shlib_undefined
5155 && ! (finfo->info->shared
5156 && !finfo->info->no_undefined)
5157 && h->root.type == bfd_link_hash_undefined
5158 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
5159 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5160 {
5161 if (! ((*finfo->info->callbacks->undefined_symbol)
5162 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
5163 (asection *) NULL, 0, true)))
5164 {
5165 eoinfo->failed = true;
5166 return false;
5167 }
5168 }
5169
5170 /* We don't want to output symbols that have never been mentioned by
5171 a regular file, or that we have been told to strip. However, if
5172 h->indx is set to -2, the symbol is used by a reloc and we must
5173 output it. */
5174 if (h->indx == -2)
5175 strip = false;
5176 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
5177 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
5178 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
5179 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5180 strip = true;
5181 else if (finfo->info->strip == strip_all
5182 || (finfo->info->strip == strip_some
5183 && bfd_hash_lookup (finfo->info->keep_hash,
5184 h->root.root.string,
5185 false, false) == NULL))
5186 strip = true;
5187 else
5188 strip = false;
5189
5190 /* If we're stripping it, and it's not a dynamic symbol, there's
5191 nothing else to do unless it is a forced local symbol. */
5192 if (strip
5193 && h->dynindx == -1
5194 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5195 return true;
5196
5197 sym.st_value = 0;
5198 sym.st_size = h->size;
5199 sym.st_other = h->other;
5200 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5201 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5202 else if (h->root.type == bfd_link_hash_undefweak
5203 || h->root.type == bfd_link_hash_defweak)
5204 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5205 else
5206 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5207
5208 switch (h->root.type)
5209 {
5210 default:
5211 case bfd_link_hash_new:
5212 abort ();
5213 return false;
5214
5215 case bfd_link_hash_undefined:
5216 input_sec = bfd_und_section_ptr;
5217 sym.st_shndx = SHN_UNDEF;
5218 break;
5219
5220 case bfd_link_hash_undefweak:
5221 input_sec = bfd_und_section_ptr;
5222 sym.st_shndx = SHN_UNDEF;
5223 break;
5224
5225 case bfd_link_hash_defined:
5226 case bfd_link_hash_defweak:
5227 {
5228 input_sec = h->root.u.def.section;
5229 if (input_sec->output_section != NULL)
5230 {
5231 sym.st_shndx =
5232 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5233 input_sec->output_section);
5234 if (sym.st_shndx == (unsigned short) -1)
5235 {
5236 (*_bfd_error_handler)
5237 (_("%s: could not find output section %s for input section %s"),
5238 bfd_get_filename (finfo->output_bfd),
5239 input_sec->output_section->name,
5240 input_sec->name);
5241 eoinfo->failed = true;
5242 return false;
5243 }
5244
5245 /* ELF symbols in relocateable files are section relative,
5246 but in nonrelocateable files they are virtual
5247 addresses. */
5248 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5249 if (! finfo->info->relocateable)
5250 sym.st_value += input_sec->output_section->vma;
5251 }
5252 else
5253 {
5254 BFD_ASSERT (input_sec->owner == NULL
5255 || (input_sec->owner->flags & DYNAMIC) != 0);
5256 sym.st_shndx = SHN_UNDEF;
5257 input_sec = bfd_und_section_ptr;
5258 }
5259 }
5260 break;
5261
5262 case bfd_link_hash_common:
5263 input_sec = h->root.u.c.p->section;
5264 sym.st_shndx = SHN_COMMON;
5265 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5266 break;
5267
5268 case bfd_link_hash_indirect:
5269 /* These symbols are created by symbol versioning. They point
5270 to the decorated version of the name. For example, if the
5271 symbol foo@@GNU_1.2 is the default, which should be used when
5272 foo is used with no version, then we add an indirect symbol
5273 foo which points to foo@@GNU_1.2. We ignore these symbols,
5274 since the indirected symbol is already in the hash table. */
5275 return true;
5276
5277 case bfd_link_hash_warning:
5278 /* We can't represent these symbols in ELF, although a warning
5279 symbol may have come from a .gnu.warning.SYMBOL section. We
5280 just put the target symbol in the hash table. If the target
5281 symbol does not really exist, don't do anything. */
5282 if (h->root.u.i.link->type == bfd_link_hash_new)
5283 return true;
5284 return (elf_link_output_extsym
5285 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5286 }
5287
5288 /* Give the processor backend a chance to tweak the symbol value,
5289 and also to finish up anything that needs to be done for this
5290 symbol. */
5291 if ((h->dynindx != -1
5292 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5293 && elf_hash_table (finfo->info)->dynamic_sections_created)
5294 {
5295 struct elf_backend_data *bed;
5296
5297 bed = get_elf_backend_data (finfo->output_bfd);
5298 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5299 (finfo->output_bfd, finfo->info, h, &sym)))
5300 {
5301 eoinfo->failed = true;
5302 return false;
5303 }
5304 }
5305
5306 /* If we are marking the symbol as undefined, and there are no
5307 non-weak references to this symbol from a regular object, then
5308 mark the symbol as weak undefined; if there are non-weak
5309 references, mark the symbol as strong. We can't do this earlier,
5310 because it might not be marked as undefined until the
5311 finish_dynamic_symbol routine gets through with it. */
5312 if (sym.st_shndx == SHN_UNDEF
5313 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5314 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5315 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5316 {
5317 int bindtype;
5318
5319 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5320 bindtype = STB_GLOBAL;
5321 else
5322 bindtype = STB_WEAK;
5323 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5324 }
5325
5326 /* If a symbol is not defined locally, we clear the visibility
5327 field. */
5328 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5329 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5330
5331 /* If this symbol should be put in the .dynsym section, then put it
5332 there now. We have already know the symbol index. We also fill
5333 in the entry in the .hash section. */
5334 if (h->dynindx != -1
5335 && elf_hash_table (finfo->info)->dynamic_sections_created)
5336 {
5337 size_t bucketcount;
5338 size_t bucket;
5339 size_t hash_entry_size;
5340 bfd_byte *bucketpos;
5341 bfd_vma chain;
5342
5343 sym.st_name = h->dynstr_index;
5344
5345 elf_swap_symbol_out (finfo->output_bfd, &sym,
5346 (PTR) (((Elf_External_Sym *)
5347 finfo->dynsym_sec->contents)
5348 + h->dynindx));
5349
5350 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5351 bucket = h->elf_hash_value % bucketcount;
5352 hash_entry_size
5353 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5354 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5355 + (bucket + 2) * hash_entry_size);
5356 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5357 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5358 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5359 ((bfd_byte *) finfo->hash_sec->contents
5360 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5361
5362 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5363 {
5364 Elf_Internal_Versym iversym;
5365
5366 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5367 {
5368 if (h->verinfo.verdef == NULL)
5369 iversym.vs_vers = 0;
5370 else
5371 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5372 }
5373 else
5374 {
5375 if (h->verinfo.vertree == NULL)
5376 iversym.vs_vers = 1;
5377 else
5378 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5379 }
5380
5381 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5382 iversym.vs_vers |= VERSYM_HIDDEN;
5383
5384 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5385 (((Elf_External_Versym *)
5386 finfo->symver_sec->contents)
5387 + h->dynindx));
5388 }
5389 }
5390
5391 /* If we're stripping it, then it was just a dynamic symbol, and
5392 there's nothing else to do. */
5393 if (strip)
5394 return true;
5395
5396 h->indx = bfd_get_symcount (finfo->output_bfd);
5397
5398 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5399 {
5400 eoinfo->failed = true;
5401 return false;
5402 }
5403
5404 return true;
5405 }
5406
5407 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5408 originated from the section given by INPUT_REL_HDR) to the
5409 OUTPUT_BFD. */
5410
5411 static void
5412 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5413 internal_relocs)
5414 bfd *output_bfd;
5415 asection *input_section;
5416 Elf_Internal_Shdr *input_rel_hdr;
5417 Elf_Internal_Rela *internal_relocs;
5418 {
5419 Elf_Internal_Rela *irela;
5420 Elf_Internal_Rela *irelaend;
5421 Elf_Internal_Shdr *output_rel_hdr;
5422 asection *output_section;
5423 unsigned int *rel_countp = NULL;
5424 struct elf_backend_data *bed;
5425
5426 output_section = input_section->output_section;
5427 output_rel_hdr = NULL;
5428
5429 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5430 == input_rel_hdr->sh_entsize)
5431 {
5432 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5433 rel_countp = &elf_section_data (output_section)->rel_count;
5434 }
5435 else if (elf_section_data (output_section)->rel_hdr2
5436 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5437 == input_rel_hdr->sh_entsize))
5438 {
5439 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5440 rel_countp = &elf_section_data (output_section)->rel_count2;
5441 }
5442
5443 BFD_ASSERT (output_rel_hdr != NULL);
5444
5445 bed = get_elf_backend_data (output_bfd);
5446 irela = internal_relocs;
5447 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5448 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5449 {
5450 Elf_External_Rel *erel;
5451
5452 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5453 for (; irela < irelaend; irela++, erel++)
5454 {
5455 Elf_Internal_Rel irel;
5456
5457 irel.r_offset = irela->r_offset;
5458 irel.r_info = irela->r_info;
5459 BFD_ASSERT (irela->r_addend == 0);
5460 if (bed->s->swap_reloc_out)
5461 (*bed->s->swap_reloc_out) (output_bfd, &irel, (PTR) erel);
5462 else
5463 elf_swap_reloc_out (output_bfd, &irel, erel);
5464 }
5465 }
5466 else
5467 {
5468 Elf_External_Rela *erela;
5469
5470 BFD_ASSERT (input_rel_hdr->sh_entsize
5471 == sizeof (Elf_External_Rela));
5472 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5473 for (; irela < irelaend; irela++, erela++)
5474 if (bed->s->swap_reloca_out)
5475 (*bed->s->swap_reloca_out) (output_bfd, irela, (PTR) erela);
5476 else
5477 elf_swap_reloca_out (output_bfd, irela, erela);
5478 }
5479
5480 /* Bump the counter, so that we know where to add the next set of
5481 relocations. */
5482 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5483 }
5484
5485 /* Link an input file into the linker output file. This function
5486 handles all the sections and relocations of the input file at once.
5487 This is so that we only have to read the local symbols once, and
5488 don't have to keep them in memory. */
5489
5490 static boolean
5491 elf_link_input_bfd (finfo, input_bfd)
5492 struct elf_final_link_info *finfo;
5493 bfd *input_bfd;
5494 {
5495 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5496 bfd *, asection *, bfd_byte *,
5497 Elf_Internal_Rela *,
5498 Elf_Internal_Sym *, asection **));
5499 bfd *output_bfd;
5500 Elf_Internal_Shdr *symtab_hdr;
5501 size_t locsymcount;
5502 size_t extsymoff;
5503 Elf_External_Sym *external_syms;
5504 Elf_External_Sym *esym;
5505 Elf_External_Sym *esymend;
5506 Elf_Internal_Sym *isym;
5507 long *pindex;
5508 asection **ppsection;
5509 asection *o;
5510 struct elf_backend_data *bed;
5511
5512 output_bfd = finfo->output_bfd;
5513 bed = get_elf_backend_data (output_bfd);
5514 relocate_section = bed->elf_backend_relocate_section;
5515
5516 /* If this is a dynamic object, we don't want to do anything here:
5517 we don't want the local symbols, and we don't want the section
5518 contents. */
5519 if ((input_bfd->flags & DYNAMIC) != 0)
5520 return true;
5521
5522 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5523 if (elf_bad_symtab (input_bfd))
5524 {
5525 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5526 extsymoff = 0;
5527 }
5528 else
5529 {
5530 locsymcount = symtab_hdr->sh_info;
5531 extsymoff = symtab_hdr->sh_info;
5532 }
5533
5534 /* Read the local symbols. */
5535 if (symtab_hdr->contents != NULL)
5536 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5537 else if (locsymcount == 0)
5538 external_syms = NULL;
5539 else
5540 {
5541 external_syms = finfo->external_syms;
5542 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5543 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5544 locsymcount, input_bfd)
5545 != locsymcount * sizeof (Elf_External_Sym)))
5546 return false;
5547 }
5548
5549 /* Swap in the local symbols and write out the ones which we know
5550 are going into the output file. */
5551 esym = external_syms;
5552 esymend = esym + locsymcount;
5553 isym = finfo->internal_syms;
5554 pindex = finfo->indices;
5555 ppsection = finfo->sections;
5556 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5557 {
5558 asection *isec;
5559 const char *name;
5560 Elf_Internal_Sym osym;
5561
5562 elf_swap_symbol_in (input_bfd, esym, isym);
5563 *pindex = -1;
5564
5565 if (elf_bad_symtab (input_bfd))
5566 {
5567 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5568 {
5569 *ppsection = NULL;
5570 continue;
5571 }
5572 }
5573
5574 name = NULL;
5575 if (isym->st_shndx == SHN_UNDEF)
5576 {
5577 isec = bfd_und_section_ptr;
5578 name = isec->name;
5579 }
5580 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5581 {
5582 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5583 if (isec && elf_section_data (isec)->merge_info
5584 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
5585 isym->st_value =
5586 _bfd_merged_section_offset (output_bfd, &isec,
5587 elf_section_data (isec)->merge_info,
5588 isym->st_value, (bfd_vma) 0);
5589 }
5590 else if (isym->st_shndx == SHN_ABS)
5591 {
5592 isec = bfd_abs_section_ptr;
5593 name = isec->name;
5594 }
5595 else if (isym->st_shndx == SHN_COMMON)
5596 {
5597 isec = bfd_com_section_ptr;
5598 name = isec->name;
5599 }
5600 else
5601 {
5602 /* Who knows? */
5603 isec = NULL;
5604 }
5605
5606 *ppsection = isec;
5607
5608 /* Don't output the first, undefined, symbol. */
5609 if (esym == external_syms)
5610 continue;
5611
5612 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5613 {
5614 asection *ksec;
5615
5616 /* Save away all section symbol values. */
5617 if (isec != NULL)
5618 {
5619 if (name)
5620 {
5621 if (isec->symbol->value != isym->st_value)
5622 (*_bfd_error_handler)
5623 (_("%s: invalid section symbol index 0x%x (%s) ingored"),
5624 bfd_get_filename (input_bfd), isym->st_shndx,
5625 name);
5626 continue;
5627 }
5628 isec->symbol->value = isym->st_value;
5629 }
5630
5631 /* If this is a discarded link-once section symbol, update
5632 it's value to that of the kept section symbol. The
5633 linker will keep the first of any matching link-once
5634 sections, so we should have already seen it's section
5635 symbol. I trust no-one will have the bright idea of
5636 re-ordering the bfd list... */
5637 if (isec != NULL
5638 && (bfd_get_section_flags (input_bfd, isec) & SEC_LINK_ONCE) != 0
5639 && (ksec = isec->kept_section) != NULL)
5640 {
5641 isym->st_value = ksec->symbol->value;
5642
5643 /* That put the value right, but the section info is all
5644 wrong. I hope this works. */
5645 isec->output_offset = ksec->output_offset;
5646 isec->output_section = ksec->output_section;
5647 }
5648
5649 /* We never output section symbols. Instead, we use the
5650 section symbol of the corresponding section in the output
5651 file. */
5652 continue;
5653 }
5654
5655 /* If we are stripping all symbols, we don't want to output this
5656 one. */
5657 if (finfo->info->strip == strip_all)
5658 continue;
5659
5660 /* If we are discarding all local symbols, we don't want to
5661 output this one. If we are generating a relocateable output
5662 file, then some of the local symbols may be required by
5663 relocs; we output them below as we discover that they are
5664 needed. */
5665 if (finfo->info->discard == discard_all)
5666 continue;
5667
5668 /* If this symbol is defined in a section which we are
5669 discarding, we don't need to keep it, but note that
5670 linker_mark is only reliable for sections that have contents.
5671 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5672 as well as linker_mark. */
5673 if (isym->st_shndx > 0
5674 && isym->st_shndx < SHN_LORESERVE
5675 && isec != NULL
5676 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5677 || (! finfo->info->relocateable
5678 && (isec->flags & SEC_EXCLUDE) != 0)))
5679 continue;
5680
5681 /* Get the name of the symbol. */
5682 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5683 isym->st_name);
5684 if (name == NULL)
5685 return false;
5686
5687 /* See if we are discarding symbols with this name. */
5688 if ((finfo->info->strip == strip_some
5689 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5690 == NULL))
5691 || (((finfo->info->discard == discard_sec_merge
5692 && (isec->flags & SEC_MERGE) && ! finfo->info->relocateable)
5693 || finfo->info->discard == discard_l)
5694 && bfd_is_local_label_name (input_bfd, name)))
5695 continue;
5696
5697 /* If we get here, we are going to output this symbol. */
5698
5699 osym = *isym;
5700
5701 /* Adjust the section index for the output file. */
5702 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5703 isec->output_section);
5704 if (osym.st_shndx == (unsigned short) -1)
5705 return false;
5706
5707 *pindex = bfd_get_symcount (output_bfd);
5708
5709 /* ELF symbols in relocateable files are section relative, but
5710 in executable files they are virtual addresses. Note that
5711 this code assumes that all ELF sections have an associated
5712 BFD section with a reasonable value for output_offset; below
5713 we assume that they also have a reasonable value for
5714 output_section. Any special sections must be set up to meet
5715 these requirements. */
5716 osym.st_value += isec->output_offset;
5717 if (! finfo->info->relocateable)
5718 osym.st_value += isec->output_section->vma;
5719
5720 if (! elf_link_output_sym (finfo, name, &osym, isec))
5721 return false;
5722 }
5723
5724 /* Relocate the contents of each section. */
5725 for (o = input_bfd->sections; o != NULL; o = o->next)
5726 {
5727 bfd_byte *contents;
5728
5729 if (! o->linker_mark)
5730 {
5731 /* This section was omitted from the link. */
5732 continue;
5733 }
5734
5735 if ((o->flags & SEC_HAS_CONTENTS) == 0
5736 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5737 continue;
5738
5739 if ((o->flags & SEC_LINKER_CREATED) != 0)
5740 {
5741 /* Section was created by elf_link_create_dynamic_sections
5742 or somesuch. */
5743 continue;
5744 }
5745
5746 /* Get the contents of the section. They have been cached by a
5747 relaxation routine. Note that o is a section in an input
5748 file, so the contents field will not have been set by any of
5749 the routines which work on output files. */
5750 if (elf_section_data (o)->this_hdr.contents != NULL)
5751 contents = elf_section_data (o)->this_hdr.contents;
5752 else
5753 {
5754 contents = finfo->contents;
5755 if (! bfd_get_section_contents (input_bfd, o, contents,
5756 (file_ptr) 0, o->_raw_size))
5757 return false;
5758 }
5759
5760 if ((o->flags & SEC_RELOC) != 0)
5761 {
5762 Elf_Internal_Rela *internal_relocs;
5763
5764 /* Get the swapped relocs. */
5765 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5766 (input_bfd, o, finfo->external_relocs,
5767 finfo->internal_relocs, false));
5768 if (internal_relocs == NULL
5769 && o->reloc_count > 0)
5770 return false;
5771
5772 /* Relocate the section by invoking a back end routine.
5773
5774 The back end routine is responsible for adjusting the
5775 section contents as necessary, and (if using Rela relocs
5776 and generating a relocateable output file) adjusting the
5777 reloc addend as necessary.
5778
5779 The back end routine does not have to worry about setting
5780 the reloc address or the reloc symbol index.
5781
5782 The back end routine is given a pointer to the swapped in
5783 internal symbols, and can access the hash table entries
5784 for the external symbols via elf_sym_hashes (input_bfd).
5785
5786 When generating relocateable output, the back end routine
5787 must handle STB_LOCAL/STT_SECTION symbols specially. The
5788 output symbol is going to be a section symbol
5789 corresponding to the output section, which will require
5790 the addend to be adjusted. */
5791
5792 if (! (*relocate_section) (output_bfd, finfo->info,
5793 input_bfd, o, contents,
5794 internal_relocs,
5795 finfo->internal_syms,
5796 finfo->sections))
5797 return false;
5798
5799 if (finfo->info->relocateable || finfo->info->emitrelocations)
5800 {
5801 Elf_Internal_Rela *irela;
5802 Elf_Internal_Rela *irelaend;
5803 struct elf_link_hash_entry **rel_hash;
5804 Elf_Internal_Shdr *input_rel_hdr;
5805
5806 /* Adjust the reloc addresses and symbol indices. */
5807
5808 irela = internal_relocs;
5809 irelaend =
5810 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5811 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5812 + elf_section_data (o->output_section)->rel_count
5813 + elf_section_data (o->output_section)->rel_count2);
5814 for (; irela < irelaend; irela++, rel_hash++)
5815 {
5816 unsigned long r_symndx;
5817 Elf_Internal_Sym *isym;
5818 asection *sec;
5819
5820 irela->r_offset += o->output_offset;
5821
5822 /* Relocs in an executable have to be virtual addresses. */
5823 if (finfo->info->emitrelocations)
5824 irela->r_offset += o->output_section->vma;
5825
5826 r_symndx = ELF_R_SYM (irela->r_info);
5827
5828 if (r_symndx == 0)
5829 continue;
5830
5831 if (r_symndx >= locsymcount
5832 || (elf_bad_symtab (input_bfd)
5833 && finfo->sections[r_symndx] == NULL))
5834 {
5835 struct elf_link_hash_entry *rh;
5836 long indx;
5837
5838 /* This is a reloc against a global symbol. We
5839 have not yet output all the local symbols, so
5840 we do not know the symbol index of any global
5841 symbol. We set the rel_hash entry for this
5842 reloc to point to the global hash table entry
5843 for this symbol. The symbol index is then
5844 set at the end of elf_bfd_final_link. */
5845 indx = r_symndx - extsymoff;
5846 rh = elf_sym_hashes (input_bfd)[indx];
5847 while (rh->root.type == bfd_link_hash_indirect
5848 || rh->root.type == bfd_link_hash_warning)
5849 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5850
5851 /* Setting the index to -2 tells
5852 elf_link_output_extsym that this symbol is
5853 used by a reloc. */
5854 BFD_ASSERT (rh->indx < 0);
5855 rh->indx = -2;
5856
5857 *rel_hash = rh;
5858
5859 continue;
5860 }
5861
5862 /* This is a reloc against a local symbol. */
5863
5864 *rel_hash = NULL;
5865 isym = finfo->internal_syms + r_symndx;
5866 sec = finfo->sections[r_symndx];
5867 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5868 {
5869 /* I suppose the backend ought to fill in the
5870 section of any STT_SECTION symbol against a
5871 processor specific section. If we have
5872 discarded a section, the output_section will
5873 be the absolute section. */
5874 if (sec != NULL
5875 && (bfd_is_abs_section (sec)
5876 || (sec->output_section != NULL
5877 && bfd_is_abs_section (sec->output_section))))
5878 r_symndx = 0;
5879 else if (sec == NULL || sec->owner == NULL)
5880 {
5881 bfd_set_error (bfd_error_bad_value);
5882 return false;
5883 }
5884 else
5885 {
5886 r_symndx = sec->output_section->target_index;
5887 BFD_ASSERT (r_symndx != 0);
5888 }
5889 }
5890 else
5891 {
5892 if (finfo->indices[r_symndx] == -1)
5893 {
5894 unsigned long link;
5895 const char *name;
5896 asection *osec;
5897
5898 if (finfo->info->strip == strip_all)
5899 {
5900 /* You can't do ld -r -s. */
5901 bfd_set_error (bfd_error_invalid_operation);
5902 return false;
5903 }
5904
5905 /* This symbol was skipped earlier, but
5906 since it is needed by a reloc, we
5907 must output it now. */
5908 link = symtab_hdr->sh_link;
5909 name = bfd_elf_string_from_elf_section (input_bfd,
5910 link,
5911 isym->st_name);
5912 if (name == NULL)
5913 return false;
5914
5915 osec = sec->output_section;
5916 isym->st_shndx =
5917 _bfd_elf_section_from_bfd_section (output_bfd,
5918 osec);
5919 if (isym->st_shndx == (unsigned short) -1)
5920 return false;
5921
5922 isym->st_value += sec->output_offset;
5923 if (! finfo->info->relocateable)
5924 isym->st_value += osec->vma;
5925
5926 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5927
5928 if (! elf_link_output_sym (finfo, name, isym, sec))
5929 return false;
5930 }
5931
5932 r_symndx = finfo->indices[r_symndx];
5933 }
5934
5935 irela->r_info = ELF_R_INFO (r_symndx,
5936 ELF_R_TYPE (irela->r_info));
5937 }
5938
5939 /* Swap out the relocs. */
5940 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5941 elf_link_output_relocs (output_bfd, o,
5942 input_rel_hdr,
5943 internal_relocs);
5944 internal_relocs
5945 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5946 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5947 if (input_rel_hdr)
5948 elf_link_output_relocs (output_bfd, o,
5949 input_rel_hdr,
5950 internal_relocs);
5951 }
5952 }
5953
5954 /* Write out the modified section contents. */
5955 if (elf_section_data (o)->stab_info)
5956 {
5957 if (! (_bfd_write_section_stabs
5958 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5959 o, &elf_section_data (o)->stab_info, contents)))
5960 return false;
5961 }
5962 else if (elf_section_data (o)->merge_info)
5963 {
5964 if (! (_bfd_write_merged_section
5965 (output_bfd, o, elf_section_data (o)->merge_info)))
5966 return false;
5967 }
5968 else
5969 {
5970 if (! (o->flags & SEC_EXCLUDE) &&
5971 ! bfd_set_section_contents (output_bfd, o->output_section,
5972 contents, o->output_offset,
5973 (o->_cooked_size != 0
5974 ? o->_cooked_size
5975 : o->_raw_size)))
5976 return false;
5977 }
5978 }
5979
5980 return true;
5981 }
5982
5983 /* Generate a reloc when linking an ELF file. This is a reloc
5984 requested by the linker, and does come from any input file. This
5985 is used to build constructor and destructor tables when linking
5986 with -Ur. */
5987
5988 static boolean
5989 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5990 bfd *output_bfd;
5991 struct bfd_link_info *info;
5992 asection *output_section;
5993 struct bfd_link_order *link_order;
5994 {
5995 reloc_howto_type *howto;
5996 long indx;
5997 bfd_vma offset;
5998 bfd_vma addend;
5999 struct elf_link_hash_entry **rel_hash_ptr;
6000 Elf_Internal_Shdr *rel_hdr;
6001 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
6002
6003 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
6004 if (howto == NULL)
6005 {
6006 bfd_set_error (bfd_error_bad_value);
6007 return false;
6008 }
6009
6010 addend = link_order->u.reloc.p->addend;
6011
6012 /* Figure out the symbol index. */
6013 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
6014 + elf_section_data (output_section)->rel_count
6015 + elf_section_data (output_section)->rel_count2);
6016 if (link_order->type == bfd_section_reloc_link_order)
6017 {
6018 indx = link_order->u.reloc.p->u.section->target_index;
6019 BFD_ASSERT (indx != 0);
6020 *rel_hash_ptr = NULL;
6021 }
6022 else
6023 {
6024 struct elf_link_hash_entry *h;
6025
6026 /* Treat a reloc against a defined symbol as though it were
6027 actually against the section. */
6028 h = ((struct elf_link_hash_entry *)
6029 bfd_wrapped_link_hash_lookup (output_bfd, info,
6030 link_order->u.reloc.p->u.name,
6031 false, false, true));
6032 if (h != NULL
6033 && (h->root.type == bfd_link_hash_defined
6034 || h->root.type == bfd_link_hash_defweak))
6035 {
6036 asection *section;
6037
6038 section = h->root.u.def.section;
6039 indx = section->output_section->target_index;
6040 *rel_hash_ptr = NULL;
6041 /* It seems that we ought to add the symbol value to the
6042 addend here, but in practice it has already been added
6043 because it was passed to constructor_callback. */
6044 addend += section->output_section->vma + section->output_offset;
6045 }
6046 else if (h != NULL)
6047 {
6048 /* Setting the index to -2 tells elf_link_output_extsym that
6049 this symbol is used by a reloc. */
6050 h->indx = -2;
6051 *rel_hash_ptr = h;
6052 indx = 0;
6053 }
6054 else
6055 {
6056 if (! ((*info->callbacks->unattached_reloc)
6057 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
6058 (asection *) NULL, (bfd_vma) 0)))
6059 return false;
6060 indx = 0;
6061 }
6062 }
6063
6064 /* If this is an inplace reloc, we must write the addend into the
6065 object file. */
6066 if (howto->partial_inplace && addend != 0)
6067 {
6068 bfd_size_type size;
6069 bfd_reloc_status_type rstat;
6070 bfd_byte *buf;
6071 boolean ok;
6072
6073 size = bfd_get_reloc_size (howto);
6074 buf = (bfd_byte *) bfd_zmalloc (size);
6075 if (buf == (bfd_byte *) NULL)
6076 return false;
6077 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
6078 switch (rstat)
6079 {
6080 case bfd_reloc_ok:
6081 break;
6082 default:
6083 case bfd_reloc_outofrange:
6084 abort ();
6085 case bfd_reloc_overflow:
6086 if (! ((*info->callbacks->reloc_overflow)
6087 (info,
6088 (link_order->type == bfd_section_reloc_link_order
6089 ? bfd_section_name (output_bfd,
6090 link_order->u.reloc.p->u.section)
6091 : link_order->u.reloc.p->u.name),
6092 howto->name, addend, (bfd *) NULL, (asection *) NULL,
6093 (bfd_vma) 0)))
6094 {
6095 free (buf);
6096 return false;
6097 }
6098 break;
6099 }
6100 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
6101 (file_ptr) link_order->offset, size);
6102 free (buf);
6103 if (! ok)
6104 return false;
6105 }
6106
6107 /* The address of a reloc is relative to the section in a
6108 relocateable file, and is a virtual address in an executable
6109 file. */
6110 offset = link_order->offset;
6111 if (! info->relocateable)
6112 offset += output_section->vma;
6113
6114 rel_hdr = &elf_section_data (output_section)->rel_hdr;
6115
6116 if (rel_hdr->sh_type == SHT_REL)
6117 {
6118 Elf_Internal_Rel irel;
6119 Elf_External_Rel *erel;
6120
6121 irel.r_offset = offset;
6122 irel.r_info = ELF_R_INFO (indx, howto->type);
6123 erel = ((Elf_External_Rel *) rel_hdr->contents
6124 + elf_section_data (output_section)->rel_count);
6125 if (bed->s->swap_reloc_out)
6126 (*bed->s->swap_reloc_out) (output_bfd, &irel, (bfd_byte *) erel);
6127 else
6128 elf_swap_reloc_out (output_bfd, &irel, erel);
6129 }
6130 else
6131 {
6132 Elf_Internal_Rela irela;
6133 Elf_External_Rela *erela;
6134
6135 irela.r_offset = offset;
6136 irela.r_info = ELF_R_INFO (indx, howto->type);
6137 irela.r_addend = addend;
6138 erela = ((Elf_External_Rela *) rel_hdr->contents
6139 + elf_section_data (output_section)->rel_count);
6140 if (bed->s->swap_reloca_out)
6141 (*bed->s->swap_reloca_out) (output_bfd, &irela, (bfd_byte *) erela);
6142 else
6143 elf_swap_reloca_out (output_bfd, &irela, erela);
6144 }
6145
6146 ++elf_section_data (output_section)->rel_count;
6147
6148 return true;
6149 }
6150 \f
6151 /* Allocate a pointer to live in a linker created section. */
6152
6153 boolean
6154 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6155 bfd *abfd;
6156 struct bfd_link_info *info;
6157 elf_linker_section_t *lsect;
6158 struct elf_link_hash_entry *h;
6159 const Elf_Internal_Rela *rel;
6160 {
6161 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6162 elf_linker_section_pointers_t *linker_section_ptr;
6163 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6164
6165 BFD_ASSERT (lsect != NULL);
6166
6167 /* Is this a global symbol? */
6168 if (h != NULL)
6169 {
6170 /* Has this symbol already been allocated, if so, our work is done */
6171 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6172 rel->r_addend,
6173 lsect->which))
6174 return true;
6175
6176 ptr_linker_section_ptr = &h->linker_section_pointer;
6177 /* Make sure this symbol is output as a dynamic symbol. */
6178 if (h->dynindx == -1)
6179 {
6180 if (! elf_link_record_dynamic_symbol (info, h))
6181 return false;
6182 }
6183
6184 if (lsect->rel_section)
6185 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6186 }
6187
6188 else /* Allocation of a pointer to a local symbol */
6189 {
6190 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6191
6192 /* Allocate a table to hold the local symbols if first time */
6193 if (!ptr)
6194 {
6195 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6196 register unsigned int i;
6197
6198 ptr = (elf_linker_section_pointers_t **)
6199 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6200
6201 if (!ptr)
6202 return false;
6203
6204 elf_local_ptr_offsets (abfd) = ptr;
6205 for (i = 0; i < num_symbols; i++)
6206 ptr[i] = (elf_linker_section_pointers_t *)0;
6207 }
6208
6209 /* Has this symbol already been allocated, if so, our work is done */
6210 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6211 rel->r_addend,
6212 lsect->which))
6213 return true;
6214
6215 ptr_linker_section_ptr = &ptr[r_symndx];
6216
6217 if (info->shared)
6218 {
6219 /* If we are generating a shared object, we need to
6220 output a R_<xxx>_RELATIVE reloc so that the
6221 dynamic linker can adjust this GOT entry. */
6222 BFD_ASSERT (lsect->rel_section != NULL);
6223 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6224 }
6225 }
6226
6227 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6228 from internal memory. */
6229 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6230 linker_section_ptr = (elf_linker_section_pointers_t *)
6231 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6232
6233 if (!linker_section_ptr)
6234 return false;
6235
6236 linker_section_ptr->next = *ptr_linker_section_ptr;
6237 linker_section_ptr->addend = rel->r_addend;
6238 linker_section_ptr->which = lsect->which;
6239 linker_section_ptr->written_address_p = false;
6240 *ptr_linker_section_ptr = linker_section_ptr;
6241
6242 #if 0
6243 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6244 {
6245 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6246 lsect->hole_offset += ARCH_SIZE / 8;
6247 lsect->sym_offset += ARCH_SIZE / 8;
6248 if (lsect->sym_hash) /* Bump up symbol value if needed */
6249 {
6250 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6251 #ifdef DEBUG
6252 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6253 lsect->sym_hash->root.root.string,
6254 (long)ARCH_SIZE / 8,
6255 (long)lsect->sym_hash->root.u.def.value);
6256 #endif
6257 }
6258 }
6259 else
6260 #endif
6261 linker_section_ptr->offset = lsect->section->_raw_size;
6262
6263 lsect->section->_raw_size += ARCH_SIZE / 8;
6264
6265 #ifdef DEBUG
6266 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6267 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6268 #endif
6269
6270 return true;
6271 }
6272 \f
6273 #if ARCH_SIZE==64
6274 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6275 #endif
6276 #if ARCH_SIZE==32
6277 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6278 #endif
6279
6280 /* Fill in the address for a pointer generated in alinker section. */
6281
6282 bfd_vma
6283 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6284 bfd *output_bfd;
6285 bfd *input_bfd;
6286 struct bfd_link_info *info;
6287 elf_linker_section_t *lsect;
6288 struct elf_link_hash_entry *h;
6289 bfd_vma relocation;
6290 const Elf_Internal_Rela *rel;
6291 int relative_reloc;
6292 {
6293 elf_linker_section_pointers_t *linker_section_ptr;
6294
6295 BFD_ASSERT (lsect != NULL);
6296
6297 if (h != NULL) /* global symbol */
6298 {
6299 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6300 rel->r_addend,
6301 lsect->which);
6302
6303 BFD_ASSERT (linker_section_ptr != NULL);
6304
6305 if (! elf_hash_table (info)->dynamic_sections_created
6306 || (info->shared
6307 && info->symbolic
6308 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6309 {
6310 /* This is actually a static link, or it is a
6311 -Bsymbolic link and the symbol is defined
6312 locally. We must initialize this entry in the
6313 global section.
6314
6315 When doing a dynamic link, we create a .rela.<xxx>
6316 relocation entry to initialize the value. This
6317 is done in the finish_dynamic_symbol routine. */
6318 if (!linker_section_ptr->written_address_p)
6319 {
6320 linker_section_ptr->written_address_p = true;
6321 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6322 lsect->section->contents + linker_section_ptr->offset);
6323 }
6324 }
6325 }
6326 else /* local symbol */
6327 {
6328 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6329 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6330 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6331 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6332 rel->r_addend,
6333 lsect->which);
6334
6335 BFD_ASSERT (linker_section_ptr != NULL);
6336
6337 /* Write out pointer if it hasn't been rewritten out before */
6338 if (!linker_section_ptr->written_address_p)
6339 {
6340 linker_section_ptr->written_address_p = true;
6341 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6342 lsect->section->contents + linker_section_ptr->offset);
6343
6344 if (info->shared)
6345 {
6346 asection *srel = lsect->rel_section;
6347 Elf_Internal_Rela outrel;
6348
6349 /* We need to generate a relative reloc for the dynamic linker. */
6350 if (!srel)
6351 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6352 lsect->rel_name);
6353
6354 BFD_ASSERT (srel != NULL);
6355
6356 outrel.r_offset = (lsect->section->output_section->vma
6357 + lsect->section->output_offset
6358 + linker_section_ptr->offset);
6359 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6360 outrel.r_addend = 0;
6361 elf_swap_reloca_out (output_bfd, &outrel,
6362 (((Elf_External_Rela *)
6363 lsect->section->contents)
6364 + elf_section_data (lsect->section)->rel_count));
6365 ++elf_section_data (lsect->section)->rel_count;
6366 }
6367 }
6368 }
6369
6370 relocation = (lsect->section->output_offset
6371 + linker_section_ptr->offset
6372 - lsect->hole_offset
6373 - lsect->sym_offset);
6374
6375 #ifdef DEBUG
6376 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6377 lsect->name, (long)relocation, (long)relocation);
6378 #endif
6379
6380 /* Subtract out the addend, because it will get added back in by the normal
6381 processing. */
6382 return relocation - linker_section_ptr->addend;
6383 }
6384 \f
6385 /* Garbage collect unused sections. */
6386
6387 static boolean elf_gc_mark
6388 PARAMS ((struct bfd_link_info *info, asection *sec,
6389 asection * (*gc_mark_hook)
6390 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6391 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6392
6393 static boolean elf_gc_sweep
6394 PARAMS ((struct bfd_link_info *info,
6395 boolean (*gc_sweep_hook)
6396 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6397 const Elf_Internal_Rela *relocs))));
6398
6399 static boolean elf_gc_sweep_symbol
6400 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6401
6402 static boolean elf_gc_allocate_got_offsets
6403 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6404
6405 static boolean elf_gc_propagate_vtable_entries_used
6406 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6407
6408 static boolean elf_gc_smash_unused_vtentry_relocs
6409 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6410
6411 /* The mark phase of garbage collection. For a given section, mark
6412 it, and all the sections which define symbols to which it refers. */
6413
6414 static boolean
6415 elf_gc_mark (info, sec, gc_mark_hook)
6416 struct bfd_link_info *info;
6417 asection *sec;
6418 asection * (*gc_mark_hook)
6419 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6420 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6421 {
6422 boolean ret = true;
6423
6424 sec->gc_mark = 1;
6425
6426 /* Look through the section relocs. */
6427
6428 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6429 {
6430 Elf_Internal_Rela *relstart, *rel, *relend;
6431 Elf_Internal_Shdr *symtab_hdr;
6432 struct elf_link_hash_entry **sym_hashes;
6433 size_t nlocsyms;
6434 size_t extsymoff;
6435 Elf_External_Sym *locsyms, *freesyms = NULL;
6436 bfd *input_bfd = sec->owner;
6437 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6438
6439 /* GCFIXME: how to arrange so that relocs and symbols are not
6440 reread continually? */
6441
6442 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6443 sym_hashes = elf_sym_hashes (input_bfd);
6444
6445 /* Read the local symbols. */
6446 if (elf_bad_symtab (input_bfd))
6447 {
6448 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6449 extsymoff = 0;
6450 }
6451 else
6452 extsymoff = nlocsyms = symtab_hdr->sh_info;
6453 if (symtab_hdr->contents)
6454 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6455 else if (nlocsyms == 0)
6456 locsyms = NULL;
6457 else
6458 {
6459 locsyms = freesyms =
6460 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6461 if (freesyms == NULL
6462 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6463 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6464 nlocsyms, input_bfd)
6465 != nlocsyms * sizeof (Elf_External_Sym)))
6466 {
6467 ret = false;
6468 goto out1;
6469 }
6470 }
6471
6472 /* Read the relocations. */
6473 relstart = (NAME(_bfd_elf,link_read_relocs)
6474 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6475 info->keep_memory));
6476 if (relstart == NULL)
6477 {
6478 ret = false;
6479 goto out1;
6480 }
6481 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6482
6483 for (rel = relstart; rel < relend; rel++)
6484 {
6485 unsigned long r_symndx;
6486 asection *rsec;
6487 struct elf_link_hash_entry *h;
6488 Elf_Internal_Sym s;
6489
6490 r_symndx = ELF_R_SYM (rel->r_info);
6491 if (r_symndx == 0)
6492 continue;
6493
6494 if (elf_bad_symtab (sec->owner))
6495 {
6496 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6497 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6498 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6499 else
6500 {
6501 h = sym_hashes[r_symndx - extsymoff];
6502 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6503 }
6504 }
6505 else if (r_symndx >= nlocsyms)
6506 {
6507 h = sym_hashes[r_symndx - extsymoff];
6508 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6509 }
6510 else
6511 {
6512 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6513 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6514 }
6515
6516 if (rsec && !rsec->gc_mark)
6517 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6518 {
6519 ret = false;
6520 goto out2;
6521 }
6522 }
6523
6524 out2:
6525 if (!info->keep_memory)
6526 free (relstart);
6527 out1:
6528 if (freesyms)
6529 free (freesyms);
6530 }
6531
6532 return ret;
6533 }
6534
6535 /* The sweep phase of garbage collection. Remove all garbage sections. */
6536
6537 static boolean
6538 elf_gc_sweep (info, gc_sweep_hook)
6539 struct bfd_link_info *info;
6540 boolean (*gc_sweep_hook)
6541 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6542 const Elf_Internal_Rela *relocs));
6543 {
6544 bfd *sub;
6545
6546 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6547 {
6548 asection *o;
6549
6550 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6551 continue;
6552
6553 for (o = sub->sections; o != NULL; o = o->next)
6554 {
6555 /* Keep special sections. Keep .debug sections. */
6556 if ((o->flags & SEC_LINKER_CREATED)
6557 || (o->flags & SEC_DEBUGGING))
6558 o->gc_mark = 1;
6559
6560 if (o->gc_mark)
6561 continue;
6562
6563 /* Skip sweeping sections already excluded. */
6564 if (o->flags & SEC_EXCLUDE)
6565 continue;
6566
6567 /* Since this is early in the link process, it is simple
6568 to remove a section from the output. */
6569 o->flags |= SEC_EXCLUDE;
6570
6571 /* But we also have to update some of the relocation
6572 info we collected before. */
6573 if (gc_sweep_hook
6574 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6575 {
6576 Elf_Internal_Rela *internal_relocs;
6577 boolean r;
6578
6579 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6580 (o->owner, o, NULL, NULL, info->keep_memory));
6581 if (internal_relocs == NULL)
6582 return false;
6583
6584 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
6585
6586 if (!info->keep_memory)
6587 free (internal_relocs);
6588
6589 if (!r)
6590 return false;
6591 }
6592 }
6593 }
6594
6595 /* Remove the symbols that were in the swept sections from the dynamic
6596 symbol table. GCFIXME: Anyone know how to get them out of the
6597 static symbol table as well? */
6598 {
6599 int i = 0;
6600
6601 elf_link_hash_traverse (elf_hash_table (info),
6602 elf_gc_sweep_symbol,
6603 (PTR) &i);
6604
6605 elf_hash_table (info)->dynsymcount = i;
6606 }
6607
6608 return true;
6609 }
6610
6611 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6612
6613 static boolean
6614 elf_gc_sweep_symbol (h, idxptr)
6615 struct elf_link_hash_entry *h;
6616 PTR idxptr;
6617 {
6618 int *idx = (int *) idxptr;
6619
6620 if (h->dynindx != -1
6621 && ((h->root.type != bfd_link_hash_defined
6622 && h->root.type != bfd_link_hash_defweak)
6623 || h->root.u.def.section->gc_mark))
6624 h->dynindx = (*idx)++;
6625
6626 return true;
6627 }
6628
6629 /* Propogate collected vtable information. This is called through
6630 elf_link_hash_traverse. */
6631
6632 static boolean
6633 elf_gc_propagate_vtable_entries_used (h, okp)
6634 struct elf_link_hash_entry *h;
6635 PTR okp;
6636 {
6637 /* Those that are not vtables. */
6638 if (h->vtable_parent == NULL)
6639 return true;
6640
6641 /* Those vtables that do not have parents, we cannot merge. */
6642 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6643 return true;
6644
6645 /* If we've already been done, exit. */
6646 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6647 return true;
6648
6649 /* Make sure the parent's table is up to date. */
6650 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6651
6652 if (h->vtable_entries_used == NULL)
6653 {
6654 /* None of this table's entries were referenced. Re-use the
6655 parent's table. */
6656 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6657 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6658 }
6659 else
6660 {
6661 size_t n;
6662 boolean *cu, *pu;
6663
6664 /* Or the parent's entries into ours. */
6665 cu = h->vtable_entries_used;
6666 cu[-1] = true;
6667 pu = h->vtable_parent->vtable_entries_used;
6668 if (pu != NULL)
6669 {
6670 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6671 while (--n != 0)
6672 {
6673 if (*pu) *cu = true;
6674 pu++, cu++;
6675 }
6676 }
6677 }
6678
6679 return true;
6680 }
6681
6682 static boolean
6683 elf_gc_smash_unused_vtentry_relocs (h, okp)
6684 struct elf_link_hash_entry *h;
6685 PTR okp;
6686 {
6687 asection *sec;
6688 bfd_vma hstart, hend;
6689 Elf_Internal_Rela *relstart, *relend, *rel;
6690 struct elf_backend_data *bed;
6691
6692 /* Take care of both those symbols that do not describe vtables as
6693 well as those that are not loaded. */
6694 if (h->vtable_parent == NULL)
6695 return true;
6696
6697 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6698 || h->root.type == bfd_link_hash_defweak);
6699
6700 sec = h->root.u.def.section;
6701 hstart = h->root.u.def.value;
6702 hend = hstart + h->size;
6703
6704 relstart = (NAME(_bfd_elf,link_read_relocs)
6705 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6706 if (!relstart)
6707 return *(boolean *)okp = false;
6708 bed = get_elf_backend_data (sec->owner);
6709 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6710
6711 for (rel = relstart; rel < relend; ++rel)
6712 if (rel->r_offset >= hstart && rel->r_offset < hend)
6713 {
6714 /* If the entry is in use, do nothing. */
6715 if (h->vtable_entries_used
6716 && (rel->r_offset - hstart) < h->vtable_entries_size)
6717 {
6718 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6719 if (h->vtable_entries_used[entry])
6720 continue;
6721 }
6722 /* Otherwise, kill it. */
6723 rel->r_offset = rel->r_info = rel->r_addend = 0;
6724 }
6725
6726 return true;
6727 }
6728
6729 /* Do mark and sweep of unused sections. */
6730
6731 boolean
6732 elf_gc_sections (abfd, info)
6733 bfd *abfd;
6734 struct bfd_link_info *info;
6735 {
6736 boolean ok = true;
6737 bfd *sub;
6738 asection * (*gc_mark_hook)
6739 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6740 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6741
6742 if (!get_elf_backend_data (abfd)->can_gc_sections
6743 || info->relocateable || info->emitrelocations
6744 || elf_hash_table (info)->dynamic_sections_created)
6745 return true;
6746
6747 /* Apply transitive closure to the vtable entry usage info. */
6748 elf_link_hash_traverse (elf_hash_table (info),
6749 elf_gc_propagate_vtable_entries_used,
6750 (PTR) &ok);
6751 if (!ok)
6752 return false;
6753
6754 /* Kill the vtable relocations that were not used. */
6755 elf_link_hash_traverse (elf_hash_table (info),
6756 elf_gc_smash_unused_vtentry_relocs,
6757 (PTR) &ok);
6758 if (!ok)
6759 return false;
6760
6761 /* Grovel through relocs to find out who stays ... */
6762
6763 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6764 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6765 {
6766 asection *o;
6767
6768 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6769 continue;
6770
6771 for (o = sub->sections; o != NULL; o = o->next)
6772 {
6773 if (o->flags & SEC_KEEP)
6774 if (!elf_gc_mark (info, o, gc_mark_hook))
6775 return false;
6776 }
6777 }
6778
6779 /* ... and mark SEC_EXCLUDE for those that go. */
6780 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6781 return false;
6782
6783 return true;
6784 }
6785 \f
6786 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6787
6788 boolean
6789 elf_gc_record_vtinherit (abfd, sec, h, offset)
6790 bfd *abfd;
6791 asection *sec;
6792 struct elf_link_hash_entry *h;
6793 bfd_vma offset;
6794 {
6795 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6796 struct elf_link_hash_entry **search, *child;
6797 bfd_size_type extsymcount;
6798
6799 /* The sh_info field of the symtab header tells us where the
6800 external symbols start. We don't care about the local symbols at
6801 this point. */
6802 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6803 if (!elf_bad_symtab (abfd))
6804 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6805
6806 sym_hashes = elf_sym_hashes (abfd);
6807 sym_hashes_end = sym_hashes + extsymcount;
6808
6809 /* Hunt down the child symbol, which is in this section at the same
6810 offset as the relocation. */
6811 for (search = sym_hashes; search != sym_hashes_end; ++search)
6812 {
6813 if ((child = *search) != NULL
6814 && (child->root.type == bfd_link_hash_defined
6815 || child->root.type == bfd_link_hash_defweak)
6816 && child->root.u.def.section == sec
6817 && child->root.u.def.value == offset)
6818 goto win;
6819 }
6820
6821 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6822 bfd_get_filename (abfd), sec->name,
6823 (unsigned long)offset);
6824 bfd_set_error (bfd_error_invalid_operation);
6825 return false;
6826
6827 win:
6828 if (!h)
6829 {
6830 /* This *should* only be the absolute section. It could potentially
6831 be that someone has defined a non-global vtable though, which
6832 would be bad. It isn't worth paging in the local symbols to be
6833 sure though; that case should simply be handled by the assembler. */
6834
6835 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6836 }
6837 else
6838 child->vtable_parent = h;
6839
6840 return true;
6841 }
6842
6843 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6844
6845 boolean
6846 elf_gc_record_vtentry (abfd, sec, h, addend)
6847 bfd *abfd ATTRIBUTE_UNUSED;
6848 asection *sec ATTRIBUTE_UNUSED;
6849 struct elf_link_hash_entry *h;
6850 bfd_vma addend;
6851 {
6852 if (addend >= h->vtable_entries_size)
6853 {
6854 size_t size, bytes;
6855 boolean *ptr = h->vtable_entries_used;
6856
6857 /* While the symbol is undefined, we have to be prepared to handle
6858 a zero size. */
6859 if (h->root.type == bfd_link_hash_undefined)
6860 size = addend;
6861 else
6862 {
6863 size = h->size;
6864 if (size < addend)
6865 {
6866 /* Oops! We've got a reference past the defined end of
6867 the table. This is probably a bug -- shall we warn? */
6868 size = addend;
6869 }
6870 }
6871
6872 /* Allocate one extra entry for use as a "done" flag for the
6873 consolidation pass. */
6874 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6875
6876 if (ptr)
6877 {
6878 ptr = bfd_realloc (ptr - 1, bytes);
6879
6880 if (ptr != NULL)
6881 {
6882 size_t oldbytes;
6883
6884 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6885 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6886 }
6887 }
6888 else
6889 ptr = bfd_zmalloc (bytes);
6890
6891 if (ptr == NULL)
6892 return false;
6893
6894 /* And arrange for that done flag to be at index -1. */
6895 h->vtable_entries_used = ptr + 1;
6896 h->vtable_entries_size = size;
6897 }
6898
6899 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6900
6901 return true;
6902 }
6903
6904 /* And an accompanying bit to work out final got entry offsets once
6905 we're done. Should be called from final_link. */
6906
6907 boolean
6908 elf_gc_common_finalize_got_offsets (abfd, info)
6909 bfd *abfd;
6910 struct bfd_link_info *info;
6911 {
6912 bfd *i;
6913 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6914 bfd_vma gotoff;
6915
6916 /* The GOT offset is relative to the .got section, but the GOT header is
6917 put into the .got.plt section, if the backend uses it. */
6918 if (bed->want_got_plt)
6919 gotoff = 0;
6920 else
6921 gotoff = bed->got_header_size;
6922
6923 /* Do the local .got entries first. */
6924 for (i = info->input_bfds; i; i = i->link_next)
6925 {
6926 bfd_signed_vma *local_got;
6927 bfd_size_type j, locsymcount;
6928 Elf_Internal_Shdr *symtab_hdr;
6929
6930 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6931 continue;
6932
6933 local_got = elf_local_got_refcounts (i);
6934 if (!local_got)
6935 continue;
6936
6937 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6938 if (elf_bad_symtab (i))
6939 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6940 else
6941 locsymcount = symtab_hdr->sh_info;
6942
6943 for (j = 0; j < locsymcount; ++j)
6944 {
6945 if (local_got[j] > 0)
6946 {
6947 local_got[j] = gotoff;
6948 gotoff += ARCH_SIZE / 8;
6949 }
6950 else
6951 local_got[j] = (bfd_vma) -1;
6952 }
6953 }
6954
6955 /* Then the global .got entries. .plt refcounts are handled by
6956 adjust_dynamic_symbol */
6957 elf_link_hash_traverse (elf_hash_table (info),
6958 elf_gc_allocate_got_offsets,
6959 (PTR) &gotoff);
6960 return true;
6961 }
6962
6963 /* We need a special top-level link routine to convert got reference counts
6964 to real got offsets. */
6965
6966 static boolean
6967 elf_gc_allocate_got_offsets (h, offarg)
6968 struct elf_link_hash_entry *h;
6969 PTR offarg;
6970 {
6971 bfd_vma *off = (bfd_vma *) offarg;
6972
6973 if (h->got.refcount > 0)
6974 {
6975 h->got.offset = off[0];
6976 off[0] += ARCH_SIZE / 8;
6977 }
6978 else
6979 h->got.offset = (bfd_vma) -1;
6980
6981 return true;
6982 }
6983
6984 /* Many folk need no more in the way of final link than this, once
6985 got entry reference counting is enabled. */
6986
6987 boolean
6988 elf_gc_common_final_link (abfd, info)
6989 bfd *abfd;
6990 struct bfd_link_info *info;
6991 {
6992 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6993 return false;
6994
6995 /* Invoke the regular ELF backend linker to do all the work. */
6996 return elf_bfd_final_link (abfd, info);
6997 }
6998
6999 /* This function will be called though elf_link_hash_traverse to store
7000 all hash value of the exported symbols in an array. */
7001
7002 static boolean
7003 elf_collect_hash_codes (h, data)
7004 struct elf_link_hash_entry *h;
7005 PTR data;
7006 {
7007 unsigned long **valuep = (unsigned long **) data;
7008 const char *name;
7009 char *p;
7010 unsigned long ha;
7011 char *alc = NULL;
7012
7013 /* Ignore indirect symbols. These are added by the versioning code. */
7014 if (h->dynindx == -1)
7015 return true;
7016
7017 name = h->root.root.string;
7018 p = strchr (name, ELF_VER_CHR);
7019 if (p != NULL)
7020 {
7021 alc = bfd_malloc (p - name + 1);
7022 memcpy (alc, name, p - name);
7023 alc[p - name] = '\0';
7024 name = alc;
7025 }
7026
7027 /* Compute the hash value. */
7028 ha = bfd_elf_hash (name);
7029
7030 /* Store the found hash value in the array given as the argument. */
7031 *(*valuep)++ = ha;
7032
7033 /* And store it in the struct so that we can put it in the hash table
7034 later. */
7035 h->elf_hash_value = ha;
7036
7037 if (alc != NULL)
7038 free (alc);
7039
7040 return true;
7041 }
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