* elflink.h (struct elf_assign_sym_version_info): Remove member
[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 struct bfd_elf_version_tree *verdefs;
31 };
32
33 static boolean elf_link_add_object_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_link_add_archive_symbols
36 PARAMS ((bfd *, struct bfd_link_info *));
37 static boolean elf_merge_symbol
38 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
39 asection **, bfd_vma *, struct elf_link_hash_entry **,
40 boolean *, boolean *, boolean *, boolean));
41 static boolean elf_export_symbol
42 PARAMS ((struct elf_link_hash_entry *, PTR));
43 static boolean elf_fix_symbol_flags
44 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
45 static boolean elf_adjust_dynamic_symbol
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_find_version_dependencies
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_link_assign_sym_version
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_collect_hash_codes
54 PARAMS ((struct elf_link_hash_entry *, PTR));
55 static boolean elf_link_read_relocs_from_section
56 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
57 static void elf_link_output_relocs
58 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
59 static boolean elf_link_size_reloc_section
60 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
61 static void elf_link_adjust_relocs
62 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
63 struct elf_link_hash_entry **));
64
65 /* Given an ELF BFD, add symbols to the global hash table as
66 appropriate. */
67
68 boolean
69 elf_bfd_link_add_symbols (abfd, info)
70 bfd *abfd;
71 struct bfd_link_info *info;
72 {
73 switch (bfd_get_format (abfd))
74 {
75 case bfd_object:
76 return elf_link_add_object_symbols (abfd, info);
77 case bfd_archive:
78 return elf_link_add_archive_symbols (abfd, info);
79 default:
80 bfd_set_error (bfd_error_wrong_format);
81 return false;
82 }
83 }
84 \f
85 /* Return true iff this is a non-common, definition of a non-function symbol. */
86 static boolean
87 is_global_data_symbol_definition (abfd, sym)
88 bfd * abfd ATTRIBUTE_UNUSED;
89 Elf_Internal_Sym * sym;
90 {
91 /* Local symbols do not count, but target specific ones might. */
92 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
93 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
94 return false;
95
96 /* Function symbols do not count. */
97 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
98 return false;
99
100 /* If the section is undefined, then so is the symbol. */
101 if (sym->st_shndx == SHN_UNDEF)
102 return false;
103
104 /* If the symbol is defined in the common section, then
105 it is a common definition and so does not count. */
106 if (sym->st_shndx == SHN_COMMON)
107 return false;
108
109 /* If the symbol is in a target specific section then we
110 must rely upon the backend to tell us what it is. */
111 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
112 /* FIXME - this function is not coded yet:
113
114 return _bfd_is_global_symbol_definition (abfd, sym);
115
116 Instead for now assume that the definition is not global,
117 Even if this is wrong, at least the linker will behave
118 in the same way that it used to do. */
119 return false;
120
121 return true;
122 }
123
124 /* Search the symbol table of the archive element of the archive ABFD
125 whose archive map contains a mention of SYMDEF, and determine if
126 the symbol is defined in this element. */
127 static boolean
128 elf_link_is_defined_archive_symbol (abfd, symdef)
129 bfd * abfd;
130 carsym * symdef;
131 {
132 Elf_Internal_Shdr * hdr;
133 Elf_External_Sym * esym;
134 Elf_External_Sym * esymend;
135 Elf_External_Sym * buf = NULL;
136 size_t symcount;
137 size_t extsymcount;
138 size_t extsymoff;
139 boolean result = false;
140
141 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
142 if (abfd == (bfd *) NULL)
143 return false;
144
145 if (! bfd_check_format (abfd, bfd_object))
146 return false;
147
148 /* If we have already included the element containing this symbol in the
149 link then we do not need to include it again. Just claim that any symbol
150 it contains is not a definition, so that our caller will not decide to
151 (re)include this element. */
152 if (abfd->archive_pass)
153 return false;
154
155 /* Select the appropriate symbol table. */
156 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
157 hdr = &elf_tdata (abfd)->symtab_hdr;
158 else
159 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
160
161 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
162
163 /* The sh_info field of the symtab header tells us where the
164 external symbols start. We don't care about the local symbols. */
165 if (elf_bad_symtab (abfd))
166 {
167 extsymcount = symcount;
168 extsymoff = 0;
169 }
170 else
171 {
172 extsymcount = symcount - hdr->sh_info;
173 extsymoff = hdr->sh_info;
174 }
175
176 buf = ((Elf_External_Sym *)
177 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
178 if (buf == NULL && extsymcount != 0)
179 return false;
180
181 /* Read in the symbol table.
182 FIXME: This ought to be cached somewhere. */
183 if (bfd_seek (abfd,
184 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
185 SEEK_SET) != 0
186 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
187 != extsymcount * sizeof (Elf_External_Sym)))
188 {
189 free (buf);
190 return false;
191 }
192
193 /* Scan the symbol table looking for SYMDEF. */
194 esymend = buf + extsymcount;
195 for (esym = buf;
196 esym < esymend;
197 esym++)
198 {
199 Elf_Internal_Sym sym;
200 const char * name;
201
202 elf_swap_symbol_in (abfd, esym, & sym);
203
204 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
205 if (name == (const char *) NULL)
206 break;
207
208 if (strcmp (name, symdef->name) == 0)
209 {
210 result = is_global_data_symbol_definition (abfd, & sym);
211 break;
212 }
213 }
214
215 free (buf);
216
217 return result;
218 }
219 \f
220 /* Add symbols from an ELF archive file to the linker hash table. We
221 don't use _bfd_generic_link_add_archive_symbols because of a
222 problem which arises on UnixWare. The UnixWare libc.so is an
223 archive which includes an entry libc.so.1 which defines a bunch of
224 symbols. The libc.so archive also includes a number of other
225 object files, which also define symbols, some of which are the same
226 as those defined in libc.so.1. Correct linking requires that we
227 consider each object file in turn, and include it if it defines any
228 symbols we need. _bfd_generic_link_add_archive_symbols does not do
229 this; it looks through the list of undefined symbols, and includes
230 any object file which defines them. When this algorithm is used on
231 UnixWare, it winds up pulling in libc.so.1 early and defining a
232 bunch of symbols. This means that some of the other objects in the
233 archive are not included in the link, which is incorrect since they
234 precede libc.so.1 in the archive.
235
236 Fortunately, ELF archive handling is simpler than that done by
237 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
238 oddities. In ELF, if we find a symbol in the archive map, and the
239 symbol is currently undefined, we know that we must pull in that
240 object file.
241
242 Unfortunately, we do have to make multiple passes over the symbol
243 table until nothing further is resolved. */
244
245 static boolean
246 elf_link_add_archive_symbols (abfd, info)
247 bfd *abfd;
248 struct bfd_link_info *info;
249 {
250 symindex c;
251 boolean *defined = NULL;
252 boolean *included = NULL;
253 carsym *symdefs;
254 boolean loop;
255
256 if (! bfd_has_map (abfd))
257 {
258 /* An empty archive is a special case. */
259 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
260 return true;
261 bfd_set_error (bfd_error_no_armap);
262 return false;
263 }
264
265 /* Keep track of all symbols we know to be already defined, and all
266 files we know to be already included. This is to speed up the
267 second and subsequent passes. */
268 c = bfd_ardata (abfd)->symdef_count;
269 if (c == 0)
270 return true;
271 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
272 included = (boolean *) bfd_malloc (c * sizeof (boolean));
273 if (defined == (boolean *) NULL || included == (boolean *) NULL)
274 goto error_return;
275 memset (defined, 0, c * sizeof (boolean));
276 memset (included, 0, c * sizeof (boolean));
277
278 symdefs = bfd_ardata (abfd)->symdefs;
279
280 do
281 {
282 file_ptr last;
283 symindex i;
284 carsym *symdef;
285 carsym *symdefend;
286
287 loop = false;
288 last = -1;
289
290 symdef = symdefs;
291 symdefend = symdef + c;
292 for (i = 0; symdef < symdefend; symdef++, i++)
293 {
294 struct elf_link_hash_entry *h;
295 bfd *element;
296 struct bfd_link_hash_entry *undefs_tail;
297 symindex mark;
298
299 if (defined[i] || included[i])
300 continue;
301 if (symdef->file_offset == last)
302 {
303 included[i] = true;
304 continue;
305 }
306
307 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
308 false, false, false);
309
310 if (h == NULL)
311 {
312 char *p, *copy;
313
314 /* If this is a default version (the name contains @@),
315 look up the symbol again without the version. The
316 effect is that references to the symbol without the
317 version will be matched by the default symbol in the
318 archive. */
319
320 p = strchr (symdef->name, ELF_VER_CHR);
321 if (p == NULL || p[1] != ELF_VER_CHR)
322 continue;
323
324 copy = bfd_alloc (abfd, p - symdef->name + 1);
325 if (copy == NULL)
326 goto error_return;
327 memcpy (copy, symdef->name, p - symdef->name);
328 copy[p - symdef->name] = '\0';
329
330 h = elf_link_hash_lookup (elf_hash_table (info), copy,
331 false, false, false);
332
333 bfd_release (abfd, copy);
334 }
335
336 if (h == NULL)
337 continue;
338
339 if (h->root.type == bfd_link_hash_common)
340 {
341 /* We currently have a common symbol. The archive map contains
342 a reference to this symbol, so we may want to include it. We
343 only want to include it however, if this archive element
344 contains a definition of the symbol, not just another common
345 declaration of it.
346
347 Unfortunately some archivers (including GNU ar) will put
348 declarations of common symbols into their archive maps, as
349 well as real definitions, so we cannot just go by the archive
350 map alone. Instead we must read in the element's symbol
351 table and check that to see what kind of symbol definition
352 this is. */
353 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
354 continue;
355 }
356 else if (h->root.type != bfd_link_hash_undefined)
357 {
358 if (h->root.type != bfd_link_hash_undefweak)
359 defined[i] = true;
360 continue;
361 }
362
363 /* We need to include this archive member. */
364 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
365 if (element == (bfd *) NULL)
366 goto error_return;
367
368 if (! bfd_check_format (element, bfd_object))
369 goto error_return;
370
371 /* Doublecheck that we have not included this object
372 already--it should be impossible, but there may be
373 something wrong with the archive. */
374 if (element->archive_pass != 0)
375 {
376 bfd_set_error (bfd_error_bad_value);
377 goto error_return;
378 }
379 element->archive_pass = 1;
380
381 undefs_tail = info->hash->undefs_tail;
382
383 if (! (*info->callbacks->add_archive_element) (info, element,
384 symdef->name))
385 goto error_return;
386 if (! elf_link_add_object_symbols (element, info))
387 goto error_return;
388
389 /* If there are any new undefined symbols, we need to make
390 another pass through the archive in order to see whether
391 they can be defined. FIXME: This isn't perfect, because
392 common symbols wind up on undefs_tail and because an
393 undefined symbol which is defined later on in this pass
394 does not require another pass. This isn't a bug, but it
395 does make the code less efficient than it could be. */
396 if (undefs_tail != info->hash->undefs_tail)
397 loop = true;
398
399 /* Look backward to mark all symbols from this object file
400 which we have already seen in this pass. */
401 mark = i;
402 do
403 {
404 included[mark] = true;
405 if (mark == 0)
406 break;
407 --mark;
408 }
409 while (symdefs[mark].file_offset == symdef->file_offset);
410
411 /* We mark subsequent symbols from this object file as we go
412 on through the loop. */
413 last = symdef->file_offset;
414 }
415 }
416 while (loop);
417
418 free (defined);
419 free (included);
420
421 return true;
422
423 error_return:
424 if (defined != (boolean *) NULL)
425 free (defined);
426 if (included != (boolean *) NULL)
427 free (included);
428 return false;
429 }
430
431 /* This function is called when we want to define a new symbol. It
432 handles the various cases which arise when we find a definition in
433 a dynamic object, or when there is already a definition in a
434 dynamic object. The new symbol is described by NAME, SYM, PSEC,
435 and PVALUE. We set SYM_HASH to the hash table entry. We set
436 OVERRIDE if the old symbol is overriding a new definition. We set
437 TYPE_CHANGE_OK if it is OK for the type to change. We set
438 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
439 change, we mean that we shouldn't warn if the type or size does
440 change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
441 a shared object. */
442
443 static boolean
444 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
445 override, type_change_ok, size_change_ok, dt_needed)
446 bfd *abfd;
447 struct bfd_link_info *info;
448 const char *name;
449 Elf_Internal_Sym *sym;
450 asection **psec;
451 bfd_vma *pvalue;
452 struct elf_link_hash_entry **sym_hash;
453 boolean *override;
454 boolean *type_change_ok;
455 boolean *size_change_ok;
456 boolean dt_needed;
457 {
458 asection *sec;
459 struct elf_link_hash_entry *h;
460 int bind;
461 bfd *oldbfd;
462 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
463
464 *override = false;
465
466 sec = *psec;
467 bind = ELF_ST_BIND (sym->st_info);
468
469 if (! bfd_is_und_section (sec))
470 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
471 else
472 h = ((struct elf_link_hash_entry *)
473 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
474 if (h == NULL)
475 return false;
476 *sym_hash = h;
477
478 /* This code is for coping with dynamic objects, and is only useful
479 if we are doing an ELF link. */
480 if (info->hash->creator != abfd->xvec)
481 return true;
482
483 /* For merging, we only care about real symbols. */
484
485 while (h->root.type == bfd_link_hash_indirect
486 || h->root.type == bfd_link_hash_warning)
487 h = (struct elf_link_hash_entry *) h->root.u.i.link;
488
489 /* If we just created the symbol, mark it as being an ELF symbol.
490 Other than that, there is nothing to do--there is no merge issue
491 with a newly defined symbol--so we just return. */
492
493 if (h->root.type == bfd_link_hash_new)
494 {
495 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
496 return true;
497 }
498
499 /* OLDBFD is a BFD associated with the existing symbol. */
500
501 switch (h->root.type)
502 {
503 default:
504 oldbfd = NULL;
505 break;
506
507 case bfd_link_hash_undefined:
508 case bfd_link_hash_undefweak:
509 oldbfd = h->root.u.undef.abfd;
510 break;
511
512 case bfd_link_hash_defined:
513 case bfd_link_hash_defweak:
514 oldbfd = h->root.u.def.section->owner;
515 break;
516
517 case bfd_link_hash_common:
518 oldbfd = h->root.u.c.p->section->owner;
519 break;
520 }
521
522 /* In cases involving weak versioned symbols, we may wind up trying
523 to merge a symbol with itself. Catch that here, to avoid the
524 confusion that results if we try to override a symbol with
525 itself. The additional tests catch cases like
526 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
527 dynamic object, which we do want to handle here. */
528 if (abfd == oldbfd
529 && ((abfd->flags & DYNAMIC) == 0
530 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
531 return true;
532
533 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
534 respectively, is from a dynamic object. */
535
536 if ((abfd->flags & DYNAMIC) != 0)
537 newdyn = true;
538 else
539 newdyn = false;
540
541 if (oldbfd != NULL)
542 olddyn = (oldbfd->flags & DYNAMIC) != 0;
543 else
544 {
545 asection *hsec;
546
547 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
548 indices used by MIPS ELF. */
549 switch (h->root.type)
550 {
551 default:
552 hsec = NULL;
553 break;
554
555 case bfd_link_hash_defined:
556 case bfd_link_hash_defweak:
557 hsec = h->root.u.def.section;
558 break;
559
560 case bfd_link_hash_common:
561 hsec = h->root.u.c.p->section;
562 break;
563 }
564
565 if (hsec == NULL)
566 olddyn = false;
567 else
568 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
569 }
570
571 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
572 respectively, appear to be a definition rather than reference. */
573
574 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
575 newdef = false;
576 else
577 newdef = true;
578
579 if (h->root.type == bfd_link_hash_undefined
580 || h->root.type == bfd_link_hash_undefweak
581 || h->root.type == bfd_link_hash_common)
582 olddef = false;
583 else
584 olddef = true;
585
586 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
587 symbol, respectively, appears to be a common symbol in a dynamic
588 object. If a symbol appears in an uninitialized section, and is
589 not weak, and is not a function, then it may be a common symbol
590 which was resolved when the dynamic object was created. We want
591 to treat such symbols specially, because they raise special
592 considerations when setting the symbol size: if the symbol
593 appears as a common symbol in a regular object, and the size in
594 the regular object is larger, we must make sure that we use the
595 larger size. This problematic case can always be avoided in C,
596 but it must be handled correctly when using Fortran shared
597 libraries.
598
599 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
600 likewise for OLDDYNCOMMON and OLDDEF.
601
602 Note that this test is just a heuristic, and that it is quite
603 possible to have an uninitialized symbol in a shared object which
604 is really a definition, rather than a common symbol. This could
605 lead to some minor confusion when the symbol really is a common
606 symbol in some regular object. However, I think it will be
607 harmless. */
608
609 if (newdyn
610 && newdef
611 && (sec->flags & SEC_ALLOC) != 0
612 && (sec->flags & SEC_LOAD) == 0
613 && sym->st_size > 0
614 && bind != STB_WEAK
615 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
616 newdyncommon = true;
617 else
618 newdyncommon = false;
619
620 if (olddyn
621 && olddef
622 && h->root.type == bfd_link_hash_defined
623 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
624 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
625 && (h->root.u.def.section->flags & SEC_LOAD) == 0
626 && h->size > 0
627 && h->type != STT_FUNC)
628 olddyncommon = true;
629 else
630 olddyncommon = false;
631
632 /* It's OK to change the type if either the existing symbol or the
633 new symbol is weak unless it comes from a DT_NEEDED entry of
634 a shared object, in which case, the DT_NEEDED entry may not be
635 required at the run time. */
636
637 if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
638 || h->root.type == bfd_link_hash_undefweak
639 || bind == STB_WEAK)
640 *type_change_ok = true;
641
642 /* It's OK to change the size if either the existing symbol or the
643 new symbol is weak, or if the old symbol is undefined. */
644
645 if (*type_change_ok
646 || h->root.type == bfd_link_hash_undefined)
647 *size_change_ok = true;
648
649 /* If both the old and the new symbols look like common symbols in a
650 dynamic object, set the size of the symbol to the larger of the
651 two. */
652
653 if (olddyncommon
654 && newdyncommon
655 && sym->st_size != h->size)
656 {
657 /* Since we think we have two common symbols, issue a multiple
658 common warning if desired. Note that we only warn if the
659 size is different. If the size is the same, we simply let
660 the old symbol override the new one as normally happens with
661 symbols defined in dynamic objects. */
662
663 if (! ((*info->callbacks->multiple_common)
664 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
665 h->size, abfd, bfd_link_hash_common, sym->st_size)))
666 return false;
667
668 if (sym->st_size > h->size)
669 h->size = sym->st_size;
670
671 *size_change_ok = true;
672 }
673
674 /* If we are looking at a dynamic object, and we have found a
675 definition, we need to see if the symbol was already defined by
676 some other object. If so, we want to use the existing
677 definition, and we do not want to report a multiple symbol
678 definition error; we do this by clobbering *PSEC to be
679 bfd_und_section_ptr.
680
681 We treat a common symbol as a definition if the symbol in the
682 shared library is a function, since common symbols always
683 represent variables; this can cause confusion in principle, but
684 any such confusion would seem to indicate an erroneous program or
685 shared library. We also permit a common symbol in a regular
686 object to override a weak symbol in a shared object.
687
688 We prefer a non-weak definition in a shared library to a weak
689 definition in the executable unless it comes from a DT_NEEDED
690 entry of a shared object, in which case, the DT_NEEDED entry
691 may not be required at the run time. */
692
693 if (newdyn
694 && newdef
695 && (olddef
696 || (h->root.type == bfd_link_hash_common
697 && (bind == STB_WEAK
698 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
699 && (h->root.type != bfd_link_hash_defweak
700 || dt_needed
701 || bind == STB_WEAK))
702 {
703 *override = true;
704 newdef = false;
705 newdyncommon = false;
706
707 *psec = sec = bfd_und_section_ptr;
708 *size_change_ok = true;
709
710 /* If we get here when the old symbol is a common symbol, then
711 we are explicitly letting it override a weak symbol or
712 function in a dynamic object, and we don't want to warn about
713 a type change. If the old symbol is a defined symbol, a type
714 change warning may still be appropriate. */
715
716 if (h->root.type == bfd_link_hash_common)
717 *type_change_ok = true;
718 }
719
720 /* Handle the special case of an old common symbol merging with a
721 new symbol which looks like a common symbol in a shared object.
722 We change *PSEC and *PVALUE to make the new symbol look like a
723 common symbol, and let _bfd_generic_link_add_one_symbol will do
724 the right thing. */
725
726 if (newdyncommon
727 && h->root.type == bfd_link_hash_common)
728 {
729 *override = true;
730 newdef = false;
731 newdyncommon = false;
732 *pvalue = sym->st_size;
733 *psec = sec = bfd_com_section_ptr;
734 *size_change_ok = true;
735 }
736
737 /* If the old symbol is from a dynamic object, and the new symbol is
738 a definition which is not from a dynamic object, then the new
739 symbol overrides the old symbol. Symbols from regular files
740 always take precedence over symbols from dynamic objects, even if
741 they are defined after the dynamic object in the link.
742
743 As above, we again permit a common symbol in a regular object to
744 override a definition in a shared object if the shared object
745 symbol is a function or is weak.
746
747 As above, we permit a non-weak definition in a shared object to
748 override a weak definition in a regular object. */
749
750 if (! newdyn
751 && (newdef
752 || (bfd_is_com_section (sec)
753 && (h->root.type == bfd_link_hash_defweak
754 || h->type == STT_FUNC)))
755 && olddyn
756 && olddef
757 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
758 && (bind != STB_WEAK
759 || h->root.type == bfd_link_hash_defweak))
760 {
761 /* Change the hash table entry to undefined, and let
762 _bfd_generic_link_add_one_symbol do the right thing with the
763 new definition. */
764
765 h->root.type = bfd_link_hash_undefined;
766 h->root.u.undef.abfd = h->root.u.def.section->owner;
767 *size_change_ok = true;
768
769 olddef = false;
770 olddyncommon = false;
771
772 /* We again permit a type change when a common symbol may be
773 overriding a function. */
774
775 if (bfd_is_com_section (sec))
776 *type_change_ok = true;
777
778 /* This union may have been set to be non-NULL when this symbol
779 was seen in a dynamic object. We must force the union to be
780 NULL, so that it is correct for a regular symbol. */
781
782 h->verinfo.vertree = NULL;
783
784 /* In this special case, if H is the target of an indirection,
785 we want the caller to frob with H rather than with the
786 indirect symbol. That will permit the caller to redefine the
787 target of the indirection, rather than the indirect symbol
788 itself. FIXME: This will break the -y option if we store a
789 symbol with a different name. */
790 *sym_hash = h;
791 }
792
793 /* Handle the special case of a new common symbol merging with an
794 old symbol that looks like it might be a common symbol defined in
795 a shared object. Note that we have already handled the case in
796 which a new common symbol should simply override the definition
797 in the shared library. */
798
799 if (! newdyn
800 && bfd_is_com_section (sec)
801 && olddyncommon)
802 {
803 /* It would be best if we could set the hash table entry to a
804 common symbol, but we don't know what to use for the section
805 or the alignment. */
806 if (! ((*info->callbacks->multiple_common)
807 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
808 h->size, abfd, bfd_link_hash_common, sym->st_size)))
809 return false;
810
811 /* If the predumed common symbol in the dynamic object is
812 larger, pretend that the new symbol has its size. */
813
814 if (h->size > *pvalue)
815 *pvalue = h->size;
816
817 /* FIXME: We no longer know the alignment required by the symbol
818 in the dynamic object, so we just wind up using the one from
819 the regular object. */
820
821 olddef = false;
822 olddyncommon = false;
823
824 h->root.type = bfd_link_hash_undefined;
825 h->root.u.undef.abfd = h->root.u.def.section->owner;
826
827 *size_change_ok = true;
828 *type_change_ok = true;
829
830 h->verinfo.vertree = NULL;
831 }
832
833 /* Handle the special case of a weak definition in a regular object
834 followed by a non-weak definition in a shared object. In this
835 case, we prefer the definition in the shared object unless it
836 comes from a DT_NEEDED entry of a shared object, in which case,
837 the DT_NEEDED entry may not be required at the run time. */
838 if (olddef
839 && ! dt_needed
840 && h->root.type == bfd_link_hash_defweak
841 && newdef
842 && newdyn
843 && bind != STB_WEAK)
844 {
845 /* To make this work we have to frob the flags so that the rest
846 of the code does not think we are using the regular
847 definition. */
848 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
849 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
850 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
851 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
852 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
853 | ELF_LINK_HASH_DEF_DYNAMIC);
854
855 /* If H is the target of an indirection, we want the caller to
856 use H rather than the indirect symbol. Otherwise if we are
857 defining a new indirect symbol we will wind up attaching it
858 to the entry we are overriding. */
859 *sym_hash = h;
860 }
861
862 /* Handle the special case of a non-weak definition in a shared
863 object followed by a weak definition in a regular object. In
864 this case we prefer to definition in the shared object. To make
865 this work we have to tell the caller to not treat the new symbol
866 as a definition. */
867 if (olddef
868 && olddyn
869 && h->root.type != bfd_link_hash_defweak
870 && newdef
871 && ! newdyn
872 && bind == STB_WEAK)
873 *override = true;
874
875 return true;
876 }
877
878 /* Add symbols from an ELF object file to the linker hash table. */
879
880 static boolean
881 elf_link_add_object_symbols (abfd, info)
882 bfd *abfd;
883 struct bfd_link_info *info;
884 {
885 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
886 const Elf_Internal_Sym *,
887 const char **, flagword *,
888 asection **, bfd_vma *));
889 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
890 asection *, const Elf_Internal_Rela *));
891 boolean collect;
892 Elf_Internal_Shdr *hdr;
893 size_t symcount;
894 size_t extsymcount;
895 size_t extsymoff;
896 Elf_External_Sym *buf = NULL;
897 struct elf_link_hash_entry **sym_hash;
898 boolean dynamic;
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 (versymhdr->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 = basename (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 (extversym != NULL)
2190 free (extversym);
2191 return false;
2192 }
2193
2194 /* Create some sections which will be filled in with dynamic linking
2195 information. ABFD is an input file which requires dynamic sections
2196 to be created. The dynamic sections take up virtual memory space
2197 when the final executable is run, so we need to create them before
2198 addresses are assigned to the output sections. We work out the
2199 actual contents and size of these sections later. */
2200
2201 boolean
2202 elf_link_create_dynamic_sections (abfd, info)
2203 bfd *abfd;
2204 struct bfd_link_info *info;
2205 {
2206 flagword flags;
2207 register asection *s;
2208 struct elf_link_hash_entry *h;
2209 struct elf_backend_data *bed;
2210
2211 if (elf_hash_table (info)->dynamic_sections_created)
2212 return true;
2213
2214 /* Make sure that all dynamic sections use the same input BFD. */
2215 if (elf_hash_table (info)->dynobj == NULL)
2216 elf_hash_table (info)->dynobj = abfd;
2217 else
2218 abfd = elf_hash_table (info)->dynobj;
2219
2220 /* Note that we set the SEC_IN_MEMORY flag for all of these
2221 sections. */
2222 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2223 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2224
2225 /* A dynamically linked executable has a .interp section, but a
2226 shared library does not. */
2227 if (! info->shared)
2228 {
2229 s = bfd_make_section (abfd, ".interp");
2230 if (s == NULL
2231 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2232 return false;
2233 }
2234
2235 /* Create sections to hold version informations. These are removed
2236 if they are not needed. */
2237 s = bfd_make_section (abfd, ".gnu.version_d");
2238 if (s == NULL
2239 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2240 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2241 return false;
2242
2243 s = bfd_make_section (abfd, ".gnu.version");
2244 if (s == NULL
2245 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2246 || ! bfd_set_section_alignment (abfd, s, 1))
2247 return false;
2248
2249 s = bfd_make_section (abfd, ".gnu.version_r");
2250 if (s == NULL
2251 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2252 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2253 return false;
2254
2255 s = bfd_make_section (abfd, ".dynsym");
2256 if (s == NULL
2257 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2258 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2259 return false;
2260
2261 s = bfd_make_section (abfd, ".dynstr");
2262 if (s == NULL
2263 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2264 return false;
2265
2266 /* Create a strtab to hold the dynamic symbol names. */
2267 if (elf_hash_table (info)->dynstr == NULL)
2268 {
2269 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2270 if (elf_hash_table (info)->dynstr == NULL)
2271 return false;
2272 }
2273
2274 s = bfd_make_section (abfd, ".dynamic");
2275 if (s == NULL
2276 || ! bfd_set_section_flags (abfd, s, flags)
2277 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2278 return false;
2279
2280 /* The special symbol _DYNAMIC is always set to the start of the
2281 .dynamic section. This call occurs before we have processed the
2282 symbols for any dynamic object, so we don't have to worry about
2283 overriding a dynamic definition. We could set _DYNAMIC in a
2284 linker script, but we only want to define it if we are, in fact,
2285 creating a .dynamic section. We don't want to define it if there
2286 is no .dynamic section, since on some ELF platforms the start up
2287 code examines it to decide how to initialize the process. */
2288 h = NULL;
2289 if (! (_bfd_generic_link_add_one_symbol
2290 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2291 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2292 (struct bfd_link_hash_entry **) &h)))
2293 return false;
2294 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2295 h->type = STT_OBJECT;
2296
2297 if (info->shared
2298 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2299 return false;
2300
2301 bed = get_elf_backend_data (abfd);
2302
2303 s = bfd_make_section (abfd, ".hash");
2304 if (s == NULL
2305 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2306 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2307 return false;
2308 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2309
2310 /* Let the backend create the rest of the sections. This lets the
2311 backend set the right flags. The backend will normally create
2312 the .got and .plt sections. */
2313 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2314 return false;
2315
2316 elf_hash_table (info)->dynamic_sections_created = true;
2317
2318 return true;
2319 }
2320
2321 /* Add an entry to the .dynamic table. */
2322
2323 boolean
2324 elf_add_dynamic_entry (info, tag, val)
2325 struct bfd_link_info *info;
2326 bfd_vma tag;
2327 bfd_vma val;
2328 {
2329 Elf_Internal_Dyn dyn;
2330 bfd *dynobj;
2331 asection *s;
2332 size_t newsize;
2333 bfd_byte *newcontents;
2334
2335 dynobj = elf_hash_table (info)->dynobj;
2336
2337 s = bfd_get_section_by_name (dynobj, ".dynamic");
2338 BFD_ASSERT (s != NULL);
2339
2340 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2341 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2342 if (newcontents == NULL)
2343 return false;
2344
2345 dyn.d_tag = tag;
2346 dyn.d_un.d_val = val;
2347 elf_swap_dyn_out (dynobj, &dyn,
2348 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2349
2350 s->_raw_size = newsize;
2351 s->contents = newcontents;
2352
2353 return true;
2354 }
2355
2356 /* Record a new local dynamic symbol. */
2357
2358 boolean
2359 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2360 struct bfd_link_info *info;
2361 bfd *input_bfd;
2362 long input_indx;
2363 {
2364 struct elf_link_local_dynamic_entry *entry;
2365 struct elf_link_hash_table *eht;
2366 struct bfd_strtab_hash *dynstr;
2367 Elf_External_Sym esym;
2368 unsigned long dynstr_index;
2369 char *name;
2370
2371 /* See if the entry exists already. */
2372 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2373 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2374 return true;
2375
2376 entry = (struct elf_link_local_dynamic_entry *)
2377 bfd_alloc (input_bfd, sizeof (*entry));
2378 if (entry == NULL)
2379 return false;
2380
2381 /* Go find the symbol, so that we can find it's name. */
2382 if (bfd_seek (input_bfd,
2383 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2384 + input_indx * sizeof (Elf_External_Sym)),
2385 SEEK_SET) != 0
2386 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2387 != sizeof (Elf_External_Sym)))
2388 return false;
2389 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2390
2391 name = (bfd_elf_string_from_elf_section
2392 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2393 entry->isym.st_name));
2394
2395 dynstr = elf_hash_table (info)->dynstr;
2396 if (dynstr == NULL)
2397 {
2398 /* Create a strtab to hold the dynamic symbol names. */
2399 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2400 if (dynstr == NULL)
2401 return false;
2402 }
2403
2404 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2405 if (dynstr_index == (unsigned long) -1)
2406 return false;
2407 entry->isym.st_name = dynstr_index;
2408
2409 eht = elf_hash_table (info);
2410
2411 entry->next = eht->dynlocal;
2412 eht->dynlocal = entry;
2413 entry->input_bfd = input_bfd;
2414 entry->input_indx = input_indx;
2415 eht->dynsymcount++;
2416
2417 /* Whatever binding the symbol had before, it's now local. */
2418 entry->isym.st_info
2419 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2420
2421 /* The dynindx will be set at the end of size_dynamic_sections. */
2422
2423 return true;
2424 }
2425 \f
2426 /* Read and swap the relocs from the section indicated by SHDR. This
2427 may be either a REL or a RELA section. The relocations are
2428 translated into RELA relocations and stored in INTERNAL_RELOCS,
2429 which should have already been allocated to contain enough space.
2430 The EXTERNAL_RELOCS are a buffer where the external form of the
2431 relocations should be stored.
2432
2433 Returns false if something goes wrong. */
2434
2435 static boolean
2436 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2437 internal_relocs)
2438 bfd *abfd;
2439 Elf_Internal_Shdr *shdr;
2440 PTR external_relocs;
2441 Elf_Internal_Rela *internal_relocs;
2442 {
2443 struct elf_backend_data *bed;
2444
2445 /* If there aren't any relocations, that's OK. */
2446 if (!shdr)
2447 return true;
2448
2449 /* Position ourselves at the start of the section. */
2450 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2451 return false;
2452
2453 /* Read the relocations. */
2454 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2455 != shdr->sh_size)
2456 return false;
2457
2458 bed = get_elf_backend_data (abfd);
2459
2460 /* Convert the external relocations to the internal format. */
2461 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2462 {
2463 Elf_External_Rel *erel;
2464 Elf_External_Rel *erelend;
2465 Elf_Internal_Rela *irela;
2466 Elf_Internal_Rel *irel;
2467
2468 erel = (Elf_External_Rel *) external_relocs;
2469 erelend = erel + NUM_SHDR_ENTRIES (shdr);
2470 irela = internal_relocs;
2471 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2472 * sizeof (Elf_Internal_Rel)));
2473 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2474 {
2475 unsigned int i;
2476
2477 if (bed->s->swap_reloc_in)
2478 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2479 else
2480 elf_swap_reloc_in (abfd, erel, irel);
2481
2482 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2483 {
2484 irela[i].r_offset = irel[i].r_offset;
2485 irela[i].r_info = irel[i].r_info;
2486 irela[i].r_addend = 0;
2487 }
2488 }
2489 }
2490 else
2491 {
2492 Elf_External_Rela *erela;
2493 Elf_External_Rela *erelaend;
2494 Elf_Internal_Rela *irela;
2495
2496 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2497
2498 erela = (Elf_External_Rela *) external_relocs;
2499 erelaend = erela + NUM_SHDR_ENTRIES (shdr);
2500 irela = internal_relocs;
2501 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2502 {
2503 if (bed->s->swap_reloca_in)
2504 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2505 else
2506 elf_swap_reloca_in (abfd, erela, irela);
2507 }
2508 }
2509
2510 return true;
2511 }
2512
2513 /* Read and swap the relocs for a section O. They may have been
2514 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2515 not NULL, they are used as buffers to read into. They are known to
2516 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2517 the return value is allocated using either malloc or bfd_alloc,
2518 according to the KEEP_MEMORY argument. If O has two relocation
2519 sections (both REL and RELA relocations), then the REL_HDR
2520 relocations will appear first in INTERNAL_RELOCS, followed by the
2521 REL_HDR2 relocations. */
2522
2523 Elf_Internal_Rela *
2524 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2525 keep_memory)
2526 bfd *abfd;
2527 asection *o;
2528 PTR external_relocs;
2529 Elf_Internal_Rela *internal_relocs;
2530 boolean keep_memory;
2531 {
2532 Elf_Internal_Shdr *rel_hdr;
2533 PTR alloc1 = NULL;
2534 Elf_Internal_Rela *alloc2 = NULL;
2535 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2536
2537 if (elf_section_data (o)->relocs != NULL)
2538 return elf_section_data (o)->relocs;
2539
2540 if (o->reloc_count == 0)
2541 return NULL;
2542
2543 rel_hdr = &elf_section_data (o)->rel_hdr;
2544
2545 if (internal_relocs == NULL)
2546 {
2547 size_t size;
2548
2549 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2550 * sizeof (Elf_Internal_Rela));
2551 if (keep_memory)
2552 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2553 else
2554 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2555 if (internal_relocs == NULL)
2556 goto error_return;
2557 }
2558
2559 if (external_relocs == NULL)
2560 {
2561 size_t size = (size_t) rel_hdr->sh_size;
2562
2563 if (elf_section_data (o)->rel_hdr2)
2564 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2565 alloc1 = (PTR) bfd_malloc (size);
2566 if (alloc1 == NULL)
2567 goto error_return;
2568 external_relocs = alloc1;
2569 }
2570
2571 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2572 external_relocs,
2573 internal_relocs))
2574 goto error_return;
2575 if (!elf_link_read_relocs_from_section
2576 (abfd,
2577 elf_section_data (o)->rel_hdr2,
2578 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2579 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2580 * bed->s->int_rels_per_ext_rel)))
2581 goto error_return;
2582
2583 /* Cache the results for next time, if we can. */
2584 if (keep_memory)
2585 elf_section_data (o)->relocs = internal_relocs;
2586
2587 if (alloc1 != NULL)
2588 free (alloc1);
2589
2590 /* Don't free alloc2, since if it was allocated we are passing it
2591 back (under the name of internal_relocs). */
2592
2593 return internal_relocs;
2594
2595 error_return:
2596 if (alloc1 != NULL)
2597 free (alloc1);
2598 if (alloc2 != NULL)
2599 free (alloc2);
2600 return NULL;
2601 }
2602 \f
2603 /* Record an assignment to a symbol made by a linker script. We need
2604 this in case some dynamic object refers to this symbol. */
2605
2606 /*ARGSUSED*/
2607 boolean
2608 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2609 bfd *output_bfd ATTRIBUTE_UNUSED;
2610 struct bfd_link_info *info;
2611 const char *name;
2612 boolean provide;
2613 {
2614 struct elf_link_hash_entry *h;
2615
2616 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2617 return true;
2618
2619 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2620 if (h == NULL)
2621 return false;
2622
2623 if (h->root.type == bfd_link_hash_new)
2624 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2625
2626 /* If this symbol is being provided by the linker script, and it is
2627 currently defined by a dynamic object, but not by a regular
2628 object, then mark it as undefined so that the generic linker will
2629 force the correct value. */
2630 if (provide
2631 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2632 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2633 h->root.type = bfd_link_hash_undefined;
2634
2635 /* If this symbol is not being provided by the linker script, and it is
2636 currently defined by a dynamic object, but not by a regular object,
2637 then clear out any version information because the symbol will not be
2638 associated with the dynamic object any more. */
2639 if (!provide
2640 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2641 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2642 h->verinfo.verdef = NULL;
2643
2644 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2645
2646 /* When possible, keep the original type of the symbol */
2647 if (h->type == STT_NOTYPE)
2648 h->type = STT_OBJECT;
2649
2650 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2651 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2652 || info->shared)
2653 && h->dynindx == -1)
2654 {
2655 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2656 return false;
2657
2658 /* If this is a weak defined symbol, and we know a corresponding
2659 real symbol from the same dynamic object, make sure the real
2660 symbol is also made into a dynamic symbol. */
2661 if (h->weakdef != NULL
2662 && h->weakdef->dynindx == -1)
2663 {
2664 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2665 return false;
2666 }
2667 }
2668
2669 return true;
2670 }
2671 \f
2672 /* This structure is used to pass information to
2673 elf_link_assign_sym_version. */
2674
2675 struct elf_assign_sym_version_info
2676 {
2677 /* Output BFD. */
2678 bfd *output_bfd;
2679 /* General link information. */
2680 struct bfd_link_info *info;
2681 /* Version tree. */
2682 struct bfd_elf_version_tree *verdefs;
2683 /* Whether we had a failure. */
2684 boolean failed;
2685 };
2686
2687 /* This structure is used to pass information to
2688 elf_link_find_version_dependencies. */
2689
2690 struct elf_find_verdep_info
2691 {
2692 /* Output BFD. */
2693 bfd *output_bfd;
2694 /* General link information. */
2695 struct bfd_link_info *info;
2696 /* The number of dependencies. */
2697 unsigned int vers;
2698 /* Whether we had a failure. */
2699 boolean failed;
2700 };
2701
2702 /* Array used to determine the number of hash table buckets to use
2703 based on the number of symbols there are. If there are fewer than
2704 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2705 fewer than 37 we use 17 buckets, and so forth. We never use more
2706 than 32771 buckets. */
2707
2708 static const size_t elf_buckets[] =
2709 {
2710 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2711 16411, 32771, 0
2712 };
2713
2714 /* Compute bucket count for hashing table. We do not use a static set
2715 of possible tables sizes anymore. Instead we determine for all
2716 possible reasonable sizes of the table the outcome (i.e., the
2717 number of collisions etc) and choose the best solution. The
2718 weighting functions are not too simple to allow the table to grow
2719 without bounds. Instead one of the weighting factors is the size.
2720 Therefore the result is always a good payoff between few collisions
2721 (= short chain lengths) and table size. */
2722 static size_t
2723 compute_bucket_count (info)
2724 struct bfd_link_info *info;
2725 {
2726 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2727 size_t best_size = 0;
2728 unsigned long int *hashcodes;
2729 unsigned long int *hashcodesp;
2730 unsigned long int i;
2731
2732 /* Compute the hash values for all exported symbols. At the same
2733 time store the values in an array so that we could use them for
2734 optimizations. */
2735 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2736 * sizeof (unsigned long int));
2737 if (hashcodes == NULL)
2738 return 0;
2739 hashcodesp = hashcodes;
2740
2741 /* Put all hash values in HASHCODES. */
2742 elf_link_hash_traverse (elf_hash_table (info),
2743 elf_collect_hash_codes, &hashcodesp);
2744
2745 /* We have a problem here. The following code to optimize the table
2746 size requires an integer type with more the 32 bits. If
2747 BFD_HOST_U_64_BIT is set we know about such a type. */
2748 #ifdef BFD_HOST_U_64_BIT
2749 if (info->optimize == true)
2750 {
2751 unsigned long int nsyms = hashcodesp - hashcodes;
2752 size_t minsize;
2753 size_t maxsize;
2754 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2755 unsigned long int *counts ;
2756
2757 /* Possible optimization parameters: if we have NSYMS symbols we say
2758 that the hashing table must at least have NSYMS/4 and at most
2759 2*NSYMS buckets. */
2760 minsize = nsyms / 4;
2761 if (minsize == 0)
2762 minsize = 1;
2763 best_size = maxsize = nsyms * 2;
2764
2765 /* Create array where we count the collisions in. We must use bfd_malloc
2766 since the size could be large. */
2767 counts = (unsigned long int *) bfd_malloc (maxsize
2768 * sizeof (unsigned long int));
2769 if (counts == NULL)
2770 {
2771 free (hashcodes);
2772 return 0;
2773 }
2774
2775 /* Compute the "optimal" size for the hash table. The criteria is a
2776 minimal chain length. The minor criteria is (of course) the size
2777 of the table. */
2778 for (i = minsize; i < maxsize; ++i)
2779 {
2780 /* Walk through the array of hashcodes and count the collisions. */
2781 BFD_HOST_U_64_BIT max;
2782 unsigned long int j;
2783 unsigned long int fact;
2784
2785 memset (counts, '\0', i * sizeof (unsigned long int));
2786
2787 /* Determine how often each hash bucket is used. */
2788 for (j = 0; j < nsyms; ++j)
2789 ++counts[hashcodes[j] % i];
2790
2791 /* For the weight function we need some information about the
2792 pagesize on the target. This is information need not be 100%
2793 accurate. Since this information is not available (so far) we
2794 define it here to a reasonable default value. If it is crucial
2795 to have a better value some day simply define this value. */
2796 # ifndef BFD_TARGET_PAGESIZE
2797 # define BFD_TARGET_PAGESIZE (4096)
2798 # endif
2799
2800 /* We in any case need 2 + NSYMS entries for the size values and
2801 the chains. */
2802 max = (2 + nsyms) * (ARCH_SIZE / 8);
2803
2804 # if 1
2805 /* Variant 1: optimize for short chains. We add the squares
2806 of all the chain lengths (which favous many small chain
2807 over a few long chains). */
2808 for (j = 0; j < i; ++j)
2809 max += counts[j] * counts[j];
2810
2811 /* This adds penalties for the overall size of the table. */
2812 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2813 max *= fact * fact;
2814 # else
2815 /* Variant 2: Optimize a lot more for small table. Here we
2816 also add squares of the size but we also add penalties for
2817 empty slots (the +1 term). */
2818 for (j = 0; j < i; ++j)
2819 max += (1 + counts[j]) * (1 + counts[j]);
2820
2821 /* The overall size of the table is considered, but not as
2822 strong as in variant 1, where it is squared. */
2823 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2824 max *= fact;
2825 # endif
2826
2827 /* Compare with current best results. */
2828 if (max < best_chlen)
2829 {
2830 best_chlen = max;
2831 best_size = i;
2832 }
2833 }
2834
2835 free (counts);
2836 }
2837 else
2838 #endif /* defined (BFD_HOST_U_64_BIT) */
2839 {
2840 /* This is the fallback solution if no 64bit type is available or if we
2841 are not supposed to spend much time on optimizations. We select the
2842 bucket count using a fixed set of numbers. */
2843 for (i = 0; elf_buckets[i] != 0; i++)
2844 {
2845 best_size = elf_buckets[i];
2846 if (dynsymcount < elf_buckets[i + 1])
2847 break;
2848 }
2849 }
2850
2851 /* Free the arrays we needed. */
2852 free (hashcodes);
2853
2854 return best_size;
2855 }
2856
2857 /* Set up the sizes and contents of the ELF dynamic sections. This is
2858 called by the ELF linker emulation before_allocation routine. We
2859 must set the sizes of the sections before the linker sets the
2860 addresses of the various sections. */
2861
2862 boolean
2863 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2864 filter_shlib,
2865 auxiliary_filters, info, sinterpptr,
2866 verdefs)
2867 bfd *output_bfd;
2868 const char *soname;
2869 const char *rpath;
2870 const char *filter_shlib;
2871 const char * const *auxiliary_filters;
2872 struct bfd_link_info *info;
2873 asection **sinterpptr;
2874 struct bfd_elf_version_tree *verdefs;
2875 {
2876 bfd_size_type soname_indx;
2877 bfd *dynobj;
2878 struct elf_backend_data *bed;
2879 struct elf_assign_sym_version_info asvinfo;
2880
2881 *sinterpptr = NULL;
2882
2883 soname_indx = (bfd_size_type) -1;
2884
2885 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2886 return true;
2887
2888 /* The backend may have to create some sections regardless of whether
2889 we're dynamic or not. */
2890 bed = get_elf_backend_data (output_bfd);
2891 if (bed->elf_backend_always_size_sections
2892 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2893 return false;
2894
2895 dynobj = elf_hash_table (info)->dynobj;
2896
2897 /* If there were no dynamic objects in the link, there is nothing to
2898 do here. */
2899 if (dynobj == NULL)
2900 return true;
2901
2902 if (elf_hash_table (info)->dynamic_sections_created)
2903 {
2904 struct elf_info_failed eif;
2905 struct elf_link_hash_entry *h;
2906 asection *dynstr;
2907
2908 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2909 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2910
2911 if (soname != NULL)
2912 {
2913 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2914 soname, true, true);
2915 if (soname_indx == (bfd_size_type) -1
2916 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2917 return false;
2918 }
2919
2920 if (info->symbolic)
2921 {
2922 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2923 return false;
2924 info->flags |= DF_SYMBOLIC;
2925 }
2926
2927 if (rpath != NULL)
2928 {
2929 bfd_size_type indx;
2930
2931 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2932 true, true);
2933 if (indx == (bfd_size_type) -1
2934 || ! elf_add_dynamic_entry (info, DT_RPATH, indx)
2935 || (info->new_dtags
2936 && ! elf_add_dynamic_entry (info, DT_RUNPATH, indx)))
2937 return false;
2938 }
2939
2940 if (filter_shlib != NULL)
2941 {
2942 bfd_size_type indx;
2943
2944 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2945 filter_shlib, true, true);
2946 if (indx == (bfd_size_type) -1
2947 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2948 return false;
2949 }
2950
2951 if (auxiliary_filters != NULL)
2952 {
2953 const char * const *p;
2954
2955 for (p = auxiliary_filters; *p != NULL; p++)
2956 {
2957 bfd_size_type indx;
2958
2959 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2960 *p, true, true);
2961 if (indx == (bfd_size_type) -1
2962 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2963 return false;
2964 }
2965 }
2966
2967 eif.info = info;
2968 eif.verdefs = verdefs;
2969 eif.failed = false;
2970
2971 /* If we are supposed to export all symbols into the dynamic symbol
2972 table (this is not the normal case), then do so. */
2973 if (info->export_dynamic)
2974 {
2975 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2976 (PTR) &eif);
2977 if (eif.failed)
2978 return false;
2979 }
2980
2981 /* Attach all the symbols to their version information. */
2982 asvinfo.output_bfd = output_bfd;
2983 asvinfo.info = info;
2984 asvinfo.verdefs = verdefs;
2985 asvinfo.failed = false;
2986
2987 elf_link_hash_traverse (elf_hash_table (info),
2988 elf_link_assign_sym_version,
2989 (PTR) &asvinfo);
2990 if (asvinfo.failed)
2991 return false;
2992
2993 /* Find all symbols which were defined in a dynamic object and make
2994 the backend pick a reasonable value for them. */
2995 elf_link_hash_traverse (elf_hash_table (info),
2996 elf_adjust_dynamic_symbol,
2997 (PTR) &eif);
2998 if (eif.failed)
2999 return false;
3000
3001 /* Add some entries to the .dynamic section. We fill in some of the
3002 values later, in elf_bfd_final_link, but we must add the entries
3003 now so that we know the final size of the .dynamic section. */
3004
3005 /* If there are initialization and/or finalization functions to
3006 call then add the corresponding DT_INIT/DT_FINI entries. */
3007 h = (info->init_function
3008 ? elf_link_hash_lookup (elf_hash_table (info),
3009 info->init_function, false,
3010 false, false)
3011 : NULL);
3012 if (h != NULL
3013 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3014 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3015 {
3016 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
3017 return false;
3018 }
3019 h = (info->fini_function
3020 ? elf_link_hash_lookup (elf_hash_table (info),
3021 info->fini_function, false,
3022 false, false)
3023 : NULL);
3024 if (h != NULL
3025 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3026 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3027 {
3028 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
3029 return false;
3030 }
3031
3032 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
3033 /* If .dynstr is excluded from the link, we don't want any of
3034 these tags. Strictly, we should be checking each section
3035 individually; This quick check covers for the case where
3036 someone does a /DISCARD/ : { *(*) }. */
3037 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
3038 {
3039 bfd_size_type strsize;
3040
3041 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3042 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
3043 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
3044 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
3045 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
3046 || ! elf_add_dynamic_entry (info, DT_SYMENT,
3047 sizeof (Elf_External_Sym)))
3048 return false;
3049 }
3050 }
3051
3052 /* The backend must work out the sizes of all the other dynamic
3053 sections. */
3054 if (bed->elf_backend_size_dynamic_sections
3055 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
3056 return false;
3057
3058 if (elf_hash_table (info)->dynamic_sections_created)
3059 {
3060 size_t dynsymcount;
3061 asection *s;
3062 size_t bucketcount = 0;
3063 size_t hash_entry_size;
3064
3065 /* Set up the version definition section. */
3066 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3067 BFD_ASSERT (s != NULL);
3068
3069 /* We may have created additional version definitions if we are
3070 just linking a regular application. */
3071 verdefs = asvinfo.verdefs;
3072
3073 if (verdefs == NULL)
3074 _bfd_strip_section_from_output (info, s);
3075 else
3076 {
3077 unsigned int cdefs;
3078 bfd_size_type size;
3079 struct bfd_elf_version_tree *t;
3080 bfd_byte *p;
3081 Elf_Internal_Verdef def;
3082 Elf_Internal_Verdaux defaux;
3083
3084 cdefs = 0;
3085 size = 0;
3086
3087 /* Make space for the base version. */
3088 size += sizeof (Elf_External_Verdef);
3089 size += sizeof (Elf_External_Verdaux);
3090 ++cdefs;
3091
3092 for (t = verdefs; t != NULL; t = t->next)
3093 {
3094 struct bfd_elf_version_deps *n;
3095
3096 size += sizeof (Elf_External_Verdef);
3097 size += sizeof (Elf_External_Verdaux);
3098 ++cdefs;
3099
3100 for (n = t->deps; n != NULL; n = n->next)
3101 size += sizeof (Elf_External_Verdaux);
3102 }
3103
3104 s->_raw_size = size;
3105 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3106 if (s->contents == NULL && s->_raw_size != 0)
3107 return false;
3108
3109 /* Fill in the version definition section. */
3110
3111 p = s->contents;
3112
3113 def.vd_version = VER_DEF_CURRENT;
3114 def.vd_flags = VER_FLG_BASE;
3115 def.vd_ndx = 1;
3116 def.vd_cnt = 1;
3117 def.vd_aux = sizeof (Elf_External_Verdef);
3118 def.vd_next = (sizeof (Elf_External_Verdef)
3119 + sizeof (Elf_External_Verdaux));
3120
3121 if (soname_indx != (bfd_size_type) -1)
3122 {
3123 def.vd_hash = bfd_elf_hash (soname);
3124 defaux.vda_name = soname_indx;
3125 }
3126 else
3127 {
3128 const char *name;
3129 bfd_size_type indx;
3130
3131 name = basename (output_bfd->filename);
3132 def.vd_hash = bfd_elf_hash (name);
3133 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3134 name, true, false);
3135 if (indx == (bfd_size_type) -1)
3136 return false;
3137 defaux.vda_name = indx;
3138 }
3139 defaux.vda_next = 0;
3140
3141 _bfd_elf_swap_verdef_out (output_bfd, &def,
3142 (Elf_External_Verdef *)p);
3143 p += sizeof (Elf_External_Verdef);
3144 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3145 (Elf_External_Verdaux *) p);
3146 p += sizeof (Elf_External_Verdaux);
3147
3148 for (t = verdefs; t != NULL; t = t->next)
3149 {
3150 unsigned int cdeps;
3151 struct bfd_elf_version_deps *n;
3152 struct elf_link_hash_entry *h;
3153
3154 cdeps = 0;
3155 for (n = t->deps; n != NULL; n = n->next)
3156 ++cdeps;
3157
3158 /* Add a symbol representing this version. */
3159 h = NULL;
3160 if (! (_bfd_generic_link_add_one_symbol
3161 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3162 (bfd_vma) 0, (const char *) NULL, false,
3163 get_elf_backend_data (dynobj)->collect,
3164 (struct bfd_link_hash_entry **) &h)))
3165 return false;
3166 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3167 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3168 h->type = STT_OBJECT;
3169 h->verinfo.vertree = t;
3170
3171 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3172 return false;
3173
3174 def.vd_version = VER_DEF_CURRENT;
3175 def.vd_flags = 0;
3176 if (t->globals == NULL && t->locals == NULL && ! t->used)
3177 def.vd_flags |= VER_FLG_WEAK;
3178 def.vd_ndx = t->vernum + 1;
3179 def.vd_cnt = cdeps + 1;
3180 def.vd_hash = bfd_elf_hash (t->name);
3181 def.vd_aux = sizeof (Elf_External_Verdef);
3182 if (t->next != NULL)
3183 def.vd_next = (sizeof (Elf_External_Verdef)
3184 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3185 else
3186 def.vd_next = 0;
3187
3188 _bfd_elf_swap_verdef_out (output_bfd, &def,
3189 (Elf_External_Verdef *) p);
3190 p += sizeof (Elf_External_Verdef);
3191
3192 defaux.vda_name = h->dynstr_index;
3193 if (t->deps == NULL)
3194 defaux.vda_next = 0;
3195 else
3196 defaux.vda_next = sizeof (Elf_External_Verdaux);
3197 t->name_indx = defaux.vda_name;
3198
3199 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3200 (Elf_External_Verdaux *) p);
3201 p += sizeof (Elf_External_Verdaux);
3202
3203 for (n = t->deps; n != NULL; n = n->next)
3204 {
3205 if (n->version_needed == NULL)
3206 {
3207 /* This can happen if there was an error in the
3208 version script. */
3209 defaux.vda_name = 0;
3210 }
3211 else
3212 defaux.vda_name = n->version_needed->name_indx;
3213 if (n->next == NULL)
3214 defaux.vda_next = 0;
3215 else
3216 defaux.vda_next = sizeof (Elf_External_Verdaux);
3217
3218 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3219 (Elf_External_Verdaux *) p);
3220 p += sizeof (Elf_External_Verdaux);
3221 }
3222 }
3223
3224 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3225 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3226 return false;
3227
3228 elf_tdata (output_bfd)->cverdefs = cdefs;
3229 }
3230
3231 if (info->new_dtags && info->flags)
3232 {
3233 if (! elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
3234 return false;
3235 }
3236
3237 if (info->flags_1)
3238 {
3239 if (! info->shared)
3240 info->flags_1 &= ~ (DF_1_INITFIRST
3241 | DF_1_NODELETE
3242 | DF_1_NOOPEN);
3243 if (! elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
3244 return false;
3245 }
3246
3247 /* Work out the size of the version reference section. */
3248
3249 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3250 BFD_ASSERT (s != NULL);
3251 {
3252 struct elf_find_verdep_info sinfo;
3253
3254 sinfo.output_bfd = output_bfd;
3255 sinfo.info = info;
3256 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3257 if (sinfo.vers == 0)
3258 sinfo.vers = 1;
3259 sinfo.failed = false;
3260
3261 elf_link_hash_traverse (elf_hash_table (info),
3262 elf_link_find_version_dependencies,
3263 (PTR) &sinfo);
3264
3265 if (elf_tdata (output_bfd)->verref == NULL)
3266 _bfd_strip_section_from_output (info, s);
3267 else
3268 {
3269 Elf_Internal_Verneed *t;
3270 unsigned int size;
3271 unsigned int crefs;
3272 bfd_byte *p;
3273
3274 /* Build the version definition section. */
3275 size = 0;
3276 crefs = 0;
3277 for (t = elf_tdata (output_bfd)->verref;
3278 t != NULL;
3279 t = t->vn_nextref)
3280 {
3281 Elf_Internal_Vernaux *a;
3282
3283 size += sizeof (Elf_External_Verneed);
3284 ++crefs;
3285 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3286 size += sizeof (Elf_External_Vernaux);
3287 }
3288
3289 s->_raw_size = size;
3290 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3291 if (s->contents == NULL)
3292 return false;
3293
3294 p = s->contents;
3295 for (t = elf_tdata (output_bfd)->verref;
3296 t != NULL;
3297 t = t->vn_nextref)
3298 {
3299 unsigned int caux;
3300 Elf_Internal_Vernaux *a;
3301 bfd_size_type indx;
3302
3303 caux = 0;
3304 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3305 ++caux;
3306
3307 t->vn_version = VER_NEED_CURRENT;
3308 t->vn_cnt = caux;
3309 if (elf_dt_name (t->vn_bfd) != NULL)
3310 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3311 elf_dt_name (t->vn_bfd),
3312 true, false);
3313 else
3314 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3315 basename (t->vn_bfd->filename),
3316 true, false);
3317 if (indx == (bfd_size_type) -1)
3318 return false;
3319 t->vn_file = indx;
3320 t->vn_aux = sizeof (Elf_External_Verneed);
3321 if (t->vn_nextref == NULL)
3322 t->vn_next = 0;
3323 else
3324 t->vn_next = (sizeof (Elf_External_Verneed)
3325 + caux * sizeof (Elf_External_Vernaux));
3326
3327 _bfd_elf_swap_verneed_out (output_bfd, t,
3328 (Elf_External_Verneed *) p);
3329 p += sizeof (Elf_External_Verneed);
3330
3331 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3332 {
3333 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3334 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3335 a->vna_nodename, true, false);
3336 if (indx == (bfd_size_type) -1)
3337 return false;
3338 a->vna_name = indx;
3339 if (a->vna_nextptr == NULL)
3340 a->vna_next = 0;
3341 else
3342 a->vna_next = sizeof (Elf_External_Vernaux);
3343
3344 _bfd_elf_swap_vernaux_out (output_bfd, a,
3345 (Elf_External_Vernaux *) p);
3346 p += sizeof (Elf_External_Vernaux);
3347 }
3348 }
3349
3350 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3351 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3352 return false;
3353
3354 elf_tdata (output_bfd)->cverrefs = crefs;
3355 }
3356 }
3357
3358 /* Assign dynsym indicies. In a shared library we generate a
3359 section symbol for each output section, which come first.
3360 Next come all of the back-end allocated local dynamic syms,
3361 followed by the rest of the global symbols. */
3362
3363 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3364
3365 /* Work out the size of the symbol version section. */
3366 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3367 BFD_ASSERT (s != NULL);
3368 if (dynsymcount == 0
3369 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3370 {
3371 _bfd_strip_section_from_output (info, s);
3372 /* The DYNSYMCOUNT might have changed if we were going to
3373 output a dynamic symbol table entry for S. */
3374 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3375 }
3376 else
3377 {
3378 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3379 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3380 if (s->contents == NULL)
3381 return false;
3382
3383 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3384 return false;
3385 }
3386
3387 /* Set the size of the .dynsym and .hash sections. We counted
3388 the number of dynamic symbols in elf_link_add_object_symbols.
3389 We will build the contents of .dynsym and .hash when we build
3390 the final symbol table, because until then we do not know the
3391 correct value to give the symbols. We built the .dynstr
3392 section as we went along in elf_link_add_object_symbols. */
3393 s = bfd_get_section_by_name (dynobj, ".dynsym");
3394 BFD_ASSERT (s != NULL);
3395 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3396 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3397 if (s->contents == NULL && s->_raw_size != 0)
3398 return false;
3399
3400 if (dynsymcount != 0)
3401 {
3402 Elf_Internal_Sym isym;
3403
3404 /* The first entry in .dynsym is a dummy symbol. */
3405 isym.st_value = 0;
3406 isym.st_size = 0;
3407 isym.st_name = 0;
3408 isym.st_info = 0;
3409 isym.st_other = 0;
3410 isym.st_shndx = 0;
3411 elf_swap_symbol_out (output_bfd, &isym,
3412 (PTR) (Elf_External_Sym *) s->contents);
3413 }
3414
3415 /* Compute the size of the hashing table. As a side effect this
3416 computes the hash values for all the names we export. */
3417 bucketcount = compute_bucket_count (info);
3418
3419 s = bfd_get_section_by_name (dynobj, ".hash");
3420 BFD_ASSERT (s != NULL);
3421 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3422 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3423 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3424 if (s->contents == NULL)
3425 return false;
3426 memset (s->contents, 0, (size_t) s->_raw_size);
3427
3428 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3429 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3430 s->contents + hash_entry_size);
3431
3432 elf_hash_table (info)->bucketcount = bucketcount;
3433
3434 s = bfd_get_section_by_name (dynobj, ".dynstr");
3435 BFD_ASSERT (s != NULL);
3436 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3437
3438 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3439 return false;
3440 }
3441
3442 return true;
3443 }
3444 \f
3445 /* Fix up the flags for a symbol. This handles various cases which
3446 can only be fixed after all the input files are seen. This is
3447 currently called by both adjust_dynamic_symbol and
3448 assign_sym_version, which is unnecessary but perhaps more robust in
3449 the face of future changes. */
3450
3451 static boolean
3452 elf_fix_symbol_flags (h, eif)
3453 struct elf_link_hash_entry *h;
3454 struct elf_info_failed *eif;
3455 {
3456 /* If this symbol was mentioned in a non-ELF file, try to set
3457 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3458 permit a non-ELF file to correctly refer to a symbol defined in
3459 an ELF dynamic object. */
3460 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3461 {
3462 while (h->root.type == bfd_link_hash_indirect)
3463 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3464
3465 if (h->root.type != bfd_link_hash_defined
3466 && h->root.type != bfd_link_hash_defweak)
3467 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3468 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3469 else
3470 {
3471 if (h->root.u.def.section->owner != NULL
3472 && (bfd_get_flavour (h->root.u.def.section->owner)
3473 == bfd_target_elf_flavour))
3474 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3475 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3476 else
3477 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3478 }
3479
3480 if (h->dynindx == -1
3481 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3482 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3483 {
3484 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3485 {
3486 eif->failed = true;
3487 return false;
3488 }
3489 }
3490 }
3491 else
3492 {
3493 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3494 was first seen in a non-ELF file. Fortunately, if the symbol
3495 was first seen in an ELF file, we're probably OK unless the
3496 symbol was defined in a non-ELF file. Catch that case here.
3497 FIXME: We're still in trouble if the symbol was first seen in
3498 a dynamic object, and then later in a non-ELF regular object. */
3499 if ((h->root.type == bfd_link_hash_defined
3500 || h->root.type == bfd_link_hash_defweak)
3501 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3502 && (h->root.u.def.section->owner != NULL
3503 ? (bfd_get_flavour (h->root.u.def.section->owner)
3504 != bfd_target_elf_flavour)
3505 : (bfd_is_abs_section (h->root.u.def.section)
3506 && (h->elf_link_hash_flags
3507 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3508 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3509 }
3510
3511 /* If this is a final link, and the symbol was defined as a common
3512 symbol in a regular object file, and there was no definition in
3513 any dynamic object, then the linker will have allocated space for
3514 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3515 flag will not have been set. */
3516 if (h->root.type == bfd_link_hash_defined
3517 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3518 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3519 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3520 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3521 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3522
3523 /* If -Bsymbolic was used (which means to bind references to global
3524 symbols to the definition within the shared object), and this
3525 symbol was defined in a regular object, then it actually doesn't
3526 need a PLT entry, and we can accomplish that by forcing it local.
3527 Likewise, if the symbol has hidden or internal visibility.
3528 FIXME: It might be that we also do not need a PLT for other
3529 non-hidden visibilities, but we would have to tell that to the
3530 backend specifically; we can't just clear PLT-related data here. */
3531 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3532 && eif->info->shared
3533 && (eif->info->symbolic
3534 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3535 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3536 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3537 {
3538 struct elf_backend_data *bed;
3539 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
3540 if (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
3541 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
3542 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3543 (*bed->elf_backend_hide_symbol) (eif->info, h);
3544 }
3545
3546 /* If this is a weak defined symbol in a dynamic object, and we know
3547 the real definition in the dynamic object, copy interesting flags
3548 over to the real definition. */
3549 if (h->weakdef != NULL)
3550 {
3551 struct elf_link_hash_entry *weakdef;
3552
3553 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3554 || h->root.type == bfd_link_hash_defweak);
3555 weakdef = h->weakdef;
3556 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3557 || weakdef->root.type == bfd_link_hash_defweak);
3558 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3559
3560 /* If the real definition is defined by a regular object file,
3561 don't do anything special. See the longer description in
3562 elf_adjust_dynamic_symbol, below. */
3563 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3564 h->weakdef = NULL;
3565 else
3566 weakdef->elf_link_hash_flags |=
3567 (h->elf_link_hash_flags
3568 & (ELF_LINK_HASH_REF_REGULAR
3569 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3570 | ELF_LINK_NON_GOT_REF));
3571 }
3572
3573 return true;
3574 }
3575
3576 /* Make the backend pick a good value for a dynamic symbol. This is
3577 called via elf_link_hash_traverse, and also calls itself
3578 recursively. */
3579
3580 static boolean
3581 elf_adjust_dynamic_symbol (h, data)
3582 struct elf_link_hash_entry *h;
3583 PTR data;
3584 {
3585 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3586 bfd *dynobj;
3587 struct elf_backend_data *bed;
3588
3589 /* Ignore indirect symbols. These are added by the versioning code. */
3590 if (h->root.type == bfd_link_hash_indirect)
3591 return true;
3592
3593 /* Fix the symbol flags. */
3594 if (! elf_fix_symbol_flags (h, eif))
3595 return false;
3596
3597 /* If this symbol does not require a PLT entry, and it is not
3598 defined by a dynamic object, or is not referenced by a regular
3599 object, ignore it. We do have to handle a weak defined symbol,
3600 even if no regular object refers to it, if we decided to add it
3601 to the dynamic symbol table. FIXME: Do we normally need to worry
3602 about symbols which are defined by one dynamic object and
3603 referenced by another one? */
3604 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3605 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3606 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3607 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3608 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3609 {
3610 h->plt.offset = (bfd_vma) -1;
3611 return true;
3612 }
3613
3614 /* If we've already adjusted this symbol, don't do it again. This
3615 can happen via a recursive call. */
3616 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3617 return true;
3618
3619 /* Don't look at this symbol again. Note that we must set this
3620 after checking the above conditions, because we may look at a
3621 symbol once, decide not to do anything, and then get called
3622 recursively later after REF_REGULAR is set below. */
3623 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3624
3625 /* If this is a weak definition, and we know a real definition, and
3626 the real symbol is not itself defined by a regular object file,
3627 then get a good value for the real definition. We handle the
3628 real symbol first, for the convenience of the backend routine.
3629
3630 Note that there is a confusing case here. If the real definition
3631 is defined by a regular object file, we don't get the real symbol
3632 from the dynamic object, but we do get the weak symbol. If the
3633 processor backend uses a COPY reloc, then if some routine in the
3634 dynamic object changes the real symbol, we will not see that
3635 change in the corresponding weak symbol. This is the way other
3636 ELF linkers work as well, and seems to be a result of the shared
3637 library model.
3638
3639 I will clarify this issue. Most SVR4 shared libraries define the
3640 variable _timezone and define timezone as a weak synonym. The
3641 tzset call changes _timezone. If you write
3642 extern int timezone;
3643 int _timezone = 5;
3644 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3645 you might expect that, since timezone is a synonym for _timezone,
3646 the same number will print both times. However, if the processor
3647 backend uses a COPY reloc, then actually timezone will be copied
3648 into your process image, and, since you define _timezone
3649 yourself, _timezone will not. Thus timezone and _timezone will
3650 wind up at different memory locations. The tzset call will set
3651 _timezone, leaving timezone unchanged. */
3652
3653 if (h->weakdef != NULL)
3654 {
3655 /* If we get to this point, we know there is an implicit
3656 reference by a regular object file via the weak symbol H.
3657 FIXME: Is this really true? What if the traversal finds
3658 H->WEAKDEF before it finds H? */
3659 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3660
3661 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3662 return false;
3663 }
3664
3665 /* If a symbol has no type and no size and does not require a PLT
3666 entry, then we are probably about to do the wrong thing here: we
3667 are probably going to create a COPY reloc for an empty object.
3668 This case can arise when a shared object is built with assembly
3669 code, and the assembly code fails to set the symbol type. */
3670 if (h->size == 0
3671 && h->type == STT_NOTYPE
3672 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3673 (*_bfd_error_handler)
3674 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3675 h->root.root.string);
3676
3677 dynobj = elf_hash_table (eif->info)->dynobj;
3678 bed = get_elf_backend_data (dynobj);
3679 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3680 {
3681 eif->failed = true;
3682 return false;
3683 }
3684
3685 return true;
3686 }
3687 \f
3688 /* This routine is used to export all defined symbols into the dynamic
3689 symbol table. It is called via elf_link_hash_traverse. */
3690
3691 static boolean
3692 elf_export_symbol (h, data)
3693 struct elf_link_hash_entry *h;
3694 PTR data;
3695 {
3696 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3697
3698 /* Ignore indirect symbols. These are added by the versioning code. */
3699 if (h->root.type == bfd_link_hash_indirect)
3700 return true;
3701
3702 if (h->dynindx == -1
3703 && (h->elf_link_hash_flags
3704 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3705 {
3706 struct bfd_elf_version_tree *t;
3707 struct bfd_elf_version_expr *d;
3708
3709 for (t = eif->verdefs; t != NULL; t = t->next)
3710 {
3711 if (t->globals != NULL)
3712 {
3713 for (d = t->globals; d != NULL; d = d->next)
3714 {
3715 if ((*d->match) (d, h->root.root.string))
3716 goto doit;
3717 }
3718 }
3719
3720 if (t->locals != NULL)
3721 {
3722 for (d = t->locals ; d != NULL; d = d->next)
3723 {
3724 if ((*d->match) (d, h->root.root.string))
3725 return true;
3726 }
3727 }
3728 }
3729
3730 if (!eif->verdefs)
3731 {
3732 doit:
3733 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3734 {
3735 eif->failed = true;
3736 return false;
3737 }
3738 }
3739 }
3740
3741 return true;
3742 }
3743 \f
3744 /* Look through the symbols which are defined in other shared
3745 libraries and referenced here. Update the list of version
3746 dependencies. This will be put into the .gnu.version_r section.
3747 This function is called via elf_link_hash_traverse. */
3748
3749 static boolean
3750 elf_link_find_version_dependencies (h, data)
3751 struct elf_link_hash_entry *h;
3752 PTR data;
3753 {
3754 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3755 Elf_Internal_Verneed *t;
3756 Elf_Internal_Vernaux *a;
3757
3758 /* We only care about symbols defined in shared objects with version
3759 information. */
3760 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3761 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3762 || h->dynindx == -1
3763 || h->verinfo.verdef == NULL)
3764 return true;
3765
3766 /* See if we already know about this version. */
3767 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3768 {
3769 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3770 continue;
3771
3772 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3773 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3774 return true;
3775
3776 break;
3777 }
3778
3779 /* This is a new version. Add it to tree we are building. */
3780
3781 if (t == NULL)
3782 {
3783 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3784 if (t == NULL)
3785 {
3786 rinfo->failed = true;
3787 return false;
3788 }
3789
3790 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3791 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3792 elf_tdata (rinfo->output_bfd)->verref = t;
3793 }
3794
3795 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3796
3797 /* Note that we are copying a string pointer here, and testing it
3798 above. If bfd_elf_string_from_elf_section is ever changed to
3799 discard the string data when low in memory, this will have to be
3800 fixed. */
3801 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3802
3803 a->vna_flags = h->verinfo.verdef->vd_flags;
3804 a->vna_nextptr = t->vn_auxptr;
3805
3806 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3807 ++rinfo->vers;
3808
3809 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3810
3811 t->vn_auxptr = a;
3812
3813 return true;
3814 }
3815
3816 /* Figure out appropriate versions for all the symbols. We may not
3817 have the version number script until we have read all of the input
3818 files, so until that point we don't know which symbols should be
3819 local. This function is called via elf_link_hash_traverse. */
3820
3821 static boolean
3822 elf_link_assign_sym_version (h, data)
3823 struct elf_link_hash_entry *h;
3824 PTR data;
3825 {
3826 struct elf_assign_sym_version_info *sinfo =
3827 (struct elf_assign_sym_version_info *) data;
3828 struct bfd_link_info *info = sinfo->info;
3829 struct elf_backend_data *bed;
3830 struct elf_info_failed eif;
3831 char *p;
3832
3833 /* Fix the symbol flags. */
3834 eif.failed = false;
3835 eif.info = info;
3836 if (! elf_fix_symbol_flags (h, &eif))
3837 {
3838 if (eif.failed)
3839 sinfo->failed = true;
3840 return false;
3841 }
3842
3843 /* We only need version numbers for symbols defined in regular
3844 objects. */
3845 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3846 return true;
3847
3848 bed = get_elf_backend_data (sinfo->output_bfd);
3849 p = strchr (h->root.root.string, ELF_VER_CHR);
3850 if (p != NULL && h->verinfo.vertree == NULL)
3851 {
3852 struct bfd_elf_version_tree *t;
3853 boolean hidden;
3854
3855 hidden = true;
3856
3857 /* There are two consecutive ELF_VER_CHR characters if this is
3858 not a hidden symbol. */
3859 ++p;
3860 if (*p == ELF_VER_CHR)
3861 {
3862 hidden = false;
3863 ++p;
3864 }
3865
3866 /* If there is no version string, we can just return out. */
3867 if (*p == '\0')
3868 {
3869 if (hidden)
3870 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3871 return true;
3872 }
3873
3874 /* Look for the version. If we find it, it is no longer weak. */
3875 for (t = sinfo->verdefs; t != NULL; t = t->next)
3876 {
3877 if (strcmp (t->name, p) == 0)
3878 {
3879 int len;
3880 char *alc;
3881 struct bfd_elf_version_expr *d;
3882
3883 len = p - h->root.root.string;
3884 alc = bfd_alloc (sinfo->output_bfd, len);
3885 if (alc == NULL)
3886 return false;
3887 strncpy (alc, h->root.root.string, len - 1);
3888 alc[len - 1] = '\0';
3889 if (alc[len - 2] == ELF_VER_CHR)
3890 alc[len - 2] = '\0';
3891
3892 h->verinfo.vertree = t;
3893 t->used = true;
3894 d = NULL;
3895
3896 if (t->globals != NULL)
3897 {
3898 for (d = t->globals; d != NULL; d = d->next)
3899 if ((*d->match) (d, alc))
3900 break;
3901 }
3902
3903 /* See if there is anything to force this symbol to
3904 local scope. */
3905 if (d == NULL && t->locals != NULL)
3906 {
3907 for (d = t->locals; d != NULL; d = d->next)
3908 {
3909 if ((*d->match) (d, alc))
3910 {
3911 if (h->dynindx != -1
3912 && info->shared
3913 && ! info->export_dynamic)
3914 {
3915 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3916 (*bed->elf_backend_hide_symbol) (info, h);
3917 /* FIXME: The name of the symbol has
3918 already been recorded in the dynamic
3919 string table section. */
3920 }
3921
3922 break;
3923 }
3924 }
3925 }
3926
3927 bfd_release (sinfo->output_bfd, alc);
3928 break;
3929 }
3930 }
3931
3932 /* If we are building an application, we need to create a
3933 version node for this version. */
3934 if (t == NULL && ! info->shared)
3935 {
3936 struct bfd_elf_version_tree **pp;
3937 int version_index;
3938
3939 /* If we aren't going to export this symbol, we don't need
3940 to worry about it. */
3941 if (h->dynindx == -1)
3942 return true;
3943
3944 t = ((struct bfd_elf_version_tree *)
3945 bfd_alloc (sinfo->output_bfd, sizeof *t));
3946 if (t == NULL)
3947 {
3948 sinfo->failed = true;
3949 return false;
3950 }
3951
3952 t->next = NULL;
3953 t->name = p;
3954 t->globals = NULL;
3955 t->locals = NULL;
3956 t->deps = NULL;
3957 t->name_indx = (unsigned int) -1;
3958 t->used = true;
3959
3960 version_index = 1;
3961 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3962 ++version_index;
3963 t->vernum = version_index;
3964
3965 *pp = t;
3966
3967 h->verinfo.vertree = t;
3968 }
3969 else if (t == NULL)
3970 {
3971 /* We could not find the version for a symbol when
3972 generating a shared archive. Return an error. */
3973 (*_bfd_error_handler)
3974 (_("%s: undefined versioned symbol name %s"),
3975 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3976 bfd_set_error (bfd_error_bad_value);
3977 sinfo->failed = true;
3978 return false;
3979 }
3980
3981 if (hidden)
3982 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3983 }
3984
3985 /* If we don't have a version for this symbol, see if we can find
3986 something. */
3987 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3988 {
3989 struct bfd_elf_version_tree *t;
3990 struct bfd_elf_version_tree *deflt;
3991 struct bfd_elf_version_expr *d;
3992
3993 /* See if can find what version this symbol is in. If the
3994 symbol is supposed to be local, then don't actually register
3995 it. */
3996 deflt = NULL;
3997 for (t = sinfo->verdefs; t != NULL; t = t->next)
3998 {
3999 if (t->globals != NULL)
4000 {
4001 for (d = t->globals; d != NULL; d = d->next)
4002 {
4003 if ((*d->match) (d, h->root.root.string))
4004 {
4005 h->verinfo.vertree = t;
4006 break;
4007 }
4008 }
4009
4010 if (d != NULL)
4011 break;
4012 }
4013
4014 if (t->locals != NULL)
4015 {
4016 for (d = t->locals; d != NULL; d = d->next)
4017 {
4018 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
4019 deflt = t;
4020 else if ((*d->match) (d, h->root.root.string))
4021 {
4022 h->verinfo.vertree = t;
4023 if (h->dynindx != -1
4024 && info->shared
4025 && ! info->export_dynamic)
4026 {
4027 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4028 (*bed->elf_backend_hide_symbol) (info, h);
4029 /* FIXME: The name of the symbol has already
4030 been recorded in the dynamic string table
4031 section. */
4032 }
4033 break;
4034 }
4035 }
4036
4037 if (d != NULL)
4038 break;
4039 }
4040 }
4041
4042 if (deflt != NULL && h->verinfo.vertree == NULL)
4043 {
4044 h->verinfo.vertree = deflt;
4045 if (h->dynindx != -1
4046 && info->shared
4047 && ! info->export_dynamic)
4048 {
4049 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4050 (*bed->elf_backend_hide_symbol) (info, h);
4051 /* FIXME: The name of the symbol has already been
4052 recorded in the dynamic string table section. */
4053 }
4054 }
4055 }
4056
4057 return true;
4058 }
4059 \f
4060 /* Final phase of ELF linker. */
4061
4062 /* A structure we use to avoid passing large numbers of arguments. */
4063
4064 struct elf_final_link_info
4065 {
4066 /* General link information. */
4067 struct bfd_link_info *info;
4068 /* Output BFD. */
4069 bfd *output_bfd;
4070 /* Symbol string table. */
4071 struct bfd_strtab_hash *symstrtab;
4072 /* .dynsym section. */
4073 asection *dynsym_sec;
4074 /* .hash section. */
4075 asection *hash_sec;
4076 /* symbol version section (.gnu.version). */
4077 asection *symver_sec;
4078 /* Buffer large enough to hold contents of any section. */
4079 bfd_byte *contents;
4080 /* Buffer large enough to hold external relocs of any section. */
4081 PTR external_relocs;
4082 /* Buffer large enough to hold internal relocs of any section. */
4083 Elf_Internal_Rela *internal_relocs;
4084 /* Buffer large enough to hold external local symbols of any input
4085 BFD. */
4086 Elf_External_Sym *external_syms;
4087 /* Buffer large enough to hold internal local symbols of any input
4088 BFD. */
4089 Elf_Internal_Sym *internal_syms;
4090 /* Array large enough to hold a symbol index for each local symbol
4091 of any input BFD. */
4092 long *indices;
4093 /* Array large enough to hold a section pointer for each local
4094 symbol of any input BFD. */
4095 asection **sections;
4096 /* Buffer to hold swapped out symbols. */
4097 Elf_External_Sym *symbuf;
4098 /* Number of swapped out symbols in buffer. */
4099 size_t symbuf_count;
4100 /* Number of symbols which fit in symbuf. */
4101 size_t symbuf_size;
4102 };
4103
4104 static boolean elf_link_output_sym
4105 PARAMS ((struct elf_final_link_info *, const char *,
4106 Elf_Internal_Sym *, asection *));
4107 static boolean elf_link_flush_output_syms
4108 PARAMS ((struct elf_final_link_info *));
4109 static boolean elf_link_output_extsym
4110 PARAMS ((struct elf_link_hash_entry *, PTR));
4111 static boolean elf_link_sec_merge_syms
4112 PARAMS ((struct elf_link_hash_entry *, PTR));
4113 static boolean elf_link_input_bfd
4114 PARAMS ((struct elf_final_link_info *, bfd *));
4115 static boolean elf_reloc_link_order
4116 PARAMS ((bfd *, struct bfd_link_info *, asection *,
4117 struct bfd_link_order *));
4118
4119 /* This struct is used to pass information to elf_link_output_extsym. */
4120
4121 struct elf_outext_info
4122 {
4123 boolean failed;
4124 boolean localsyms;
4125 struct elf_final_link_info *finfo;
4126 };
4127
4128 /* Compute the size of, and allocate space for, REL_HDR which is the
4129 section header for a section containing relocations for O. */
4130
4131 static boolean
4132 elf_link_size_reloc_section (abfd, rel_hdr, o)
4133 bfd *abfd;
4134 Elf_Internal_Shdr *rel_hdr;
4135 asection *o;
4136 {
4137 unsigned reloc_count;
4138
4139 /* Figure out how many relocations there will be. */
4140 if (rel_hdr == &elf_section_data (o)->rel_hdr)
4141 reloc_count = elf_section_data (o)->rel_count;
4142 else
4143 reloc_count = elf_section_data (o)->rel_count2;
4144
4145 /* That allows us to calculate the size of the section. */
4146 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
4147
4148 /* The contents field must last into write_object_contents, so we
4149 allocate it with bfd_alloc rather than malloc. Also since we
4150 cannot be sure that the contents will actually be filled in,
4151 we zero the allocated space. */
4152 rel_hdr->contents = (PTR) bfd_zalloc (abfd, rel_hdr->sh_size);
4153 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
4154 return false;
4155
4156 /* We only allocate one set of hash entries, so we only do it the
4157 first time we are called. */
4158 if (elf_section_data (o)->rel_hashes == NULL)
4159 {
4160 struct elf_link_hash_entry **p;
4161
4162 p = ((struct elf_link_hash_entry **)
4163 bfd_zmalloc (o->reloc_count
4164 * sizeof (struct elf_link_hash_entry *)));
4165 if (p == NULL && o->reloc_count != 0)
4166 return false;
4167
4168 elf_section_data (o)->rel_hashes = p;
4169 }
4170
4171 return true;
4172 }
4173
4174 /* When performing a relocateable link, the input relocations are
4175 preserved. But, if they reference global symbols, the indices
4176 referenced must be updated. Update all the relocations in
4177 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4178
4179 static void
4180 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4181 bfd *abfd;
4182 Elf_Internal_Shdr *rel_hdr;
4183 unsigned int count;
4184 struct elf_link_hash_entry **rel_hash;
4185 {
4186 unsigned int i;
4187 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4188 Elf_Internal_Rel *irel;
4189 Elf_Internal_Rela *irela;
4190
4191 irel = (Elf_Internal_Rel *) bfd_zmalloc (sizeof (Elf_Internal_Rel)
4192 * bed->s->int_rels_per_ext_rel);
4193 if (irel == NULL)
4194 {
4195 (*_bfd_error_handler) (_("Error: out of memory"));
4196 abort ();
4197 }
4198
4199 irela = (Elf_Internal_Rela *) bfd_zmalloc (sizeof (Elf_Internal_Rela)
4200 * bed->s->int_rels_per_ext_rel);
4201 if (irela == NULL)
4202 {
4203 (*_bfd_error_handler) (_("Error: out of memory"));
4204 abort ();
4205 }
4206
4207 for (i = 0; i < count; i++, rel_hash++)
4208 {
4209 if (*rel_hash == NULL)
4210 continue;
4211
4212 BFD_ASSERT ((*rel_hash)->indx >= 0);
4213
4214 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4215 {
4216 Elf_External_Rel *erel;
4217 unsigned int j;
4218
4219 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4220 if (bed->s->swap_reloc_in)
4221 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
4222 else
4223 elf_swap_reloc_in (abfd, erel, irel);
4224
4225 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
4226 irel[j].r_info = ELF_R_INFO ((*rel_hash)->indx,
4227 ELF_R_TYPE (irel[j].r_info));
4228
4229 if (bed->s->swap_reloc_out)
4230 (*bed->s->swap_reloc_out) (abfd, irel, (bfd_byte *) erel);
4231 else
4232 elf_swap_reloc_out (abfd, irel, erel);
4233 }
4234 else
4235 {
4236 Elf_External_Rela *erela;
4237 unsigned int j;
4238
4239 BFD_ASSERT (rel_hdr->sh_entsize
4240 == sizeof (Elf_External_Rela));
4241
4242 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4243 if (bed->s->swap_reloca_in)
4244 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
4245 else
4246 elf_swap_reloca_in (abfd, erela, irela);
4247
4248 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
4249 irela[j].r_info = ELF_R_INFO ((*rel_hash)->indx,
4250 ELF_R_TYPE (irela[j].r_info));
4251
4252 if (bed->s->swap_reloca_out)
4253 (*bed->s->swap_reloca_out) (abfd, irela, (bfd_byte *) erela);
4254 else
4255 elf_swap_reloca_out (abfd, irela, erela);
4256 }
4257 }
4258
4259 free (irel);
4260 free (irela);
4261 }
4262
4263 /* Do the final step of an ELF link. */
4264
4265 boolean
4266 elf_bfd_final_link (abfd, info)
4267 bfd *abfd;
4268 struct bfd_link_info *info;
4269 {
4270 boolean dynamic;
4271 bfd *dynobj;
4272 struct elf_final_link_info finfo;
4273 register asection *o;
4274 register struct bfd_link_order *p;
4275 register bfd *sub;
4276 size_t max_contents_size;
4277 size_t max_external_reloc_size;
4278 size_t max_internal_reloc_count;
4279 size_t max_sym_count;
4280 file_ptr off;
4281 Elf_Internal_Sym elfsym;
4282 unsigned int i;
4283 Elf_Internal_Shdr *symtab_hdr;
4284 Elf_Internal_Shdr *symstrtab_hdr;
4285 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4286 struct elf_outext_info eoinfo;
4287 boolean merged;
4288
4289 if (info->shared)
4290 abfd->flags |= DYNAMIC;
4291
4292 dynamic = elf_hash_table (info)->dynamic_sections_created;
4293 dynobj = elf_hash_table (info)->dynobj;
4294
4295 finfo.info = info;
4296 finfo.output_bfd = abfd;
4297 finfo.symstrtab = elf_stringtab_init ();
4298 if (finfo.symstrtab == NULL)
4299 return false;
4300
4301 if (! dynamic)
4302 {
4303 finfo.dynsym_sec = NULL;
4304 finfo.hash_sec = NULL;
4305 finfo.symver_sec = NULL;
4306 }
4307 else
4308 {
4309 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4310 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4311 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4312 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4313 /* Note that it is OK if symver_sec is NULL. */
4314 }
4315
4316 finfo.contents = NULL;
4317 finfo.external_relocs = NULL;
4318 finfo.internal_relocs = NULL;
4319 finfo.external_syms = NULL;
4320 finfo.internal_syms = NULL;
4321 finfo.indices = NULL;
4322 finfo.sections = NULL;
4323 finfo.symbuf = NULL;
4324 finfo.symbuf_count = 0;
4325
4326 /* Count up the number of relocations we will output for each output
4327 section, so that we know the sizes of the reloc sections. We
4328 also figure out some maximum sizes. */
4329 max_contents_size = 0;
4330 max_external_reloc_size = 0;
4331 max_internal_reloc_count = 0;
4332 max_sym_count = 0;
4333 merged = false;
4334 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4335 {
4336 o->reloc_count = 0;
4337
4338 for (p = o->link_order_head; p != NULL; p = p->next)
4339 {
4340 if (p->type == bfd_section_reloc_link_order
4341 || p->type == bfd_symbol_reloc_link_order)
4342 ++o->reloc_count;
4343 else if (p->type == bfd_indirect_link_order)
4344 {
4345 asection *sec;
4346
4347 sec = p->u.indirect.section;
4348
4349 /* Mark all sections which are to be included in the
4350 link. This will normally be every section. We need
4351 to do this so that we can identify any sections which
4352 the linker has decided to not include. */
4353 sec->linker_mark = true;
4354
4355 if (sec->flags & SEC_MERGE)
4356 merged = true;
4357
4358 if (info->relocateable || info->emitrelocations)
4359 o->reloc_count += sec->reloc_count;
4360
4361 if (sec->_raw_size > max_contents_size)
4362 max_contents_size = sec->_raw_size;
4363 if (sec->_cooked_size > max_contents_size)
4364 max_contents_size = sec->_cooked_size;
4365
4366 /* We are interested in just local symbols, not all
4367 symbols. */
4368 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4369 && (sec->owner->flags & DYNAMIC) == 0)
4370 {
4371 size_t sym_count;
4372
4373 if (elf_bad_symtab (sec->owner))
4374 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4375 / sizeof (Elf_External_Sym));
4376 else
4377 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4378
4379 if (sym_count > max_sym_count)
4380 max_sym_count = sym_count;
4381
4382 if ((sec->flags & SEC_RELOC) != 0)
4383 {
4384 size_t ext_size;
4385
4386 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4387 if (ext_size > max_external_reloc_size)
4388 max_external_reloc_size = ext_size;
4389 if (sec->reloc_count > max_internal_reloc_count)
4390 max_internal_reloc_count = sec->reloc_count;
4391 }
4392 }
4393 }
4394 }
4395
4396 if (o->reloc_count > 0)
4397 o->flags |= SEC_RELOC;
4398 else
4399 {
4400 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4401 set it (this is probably a bug) and if it is set
4402 assign_section_numbers will create a reloc section. */
4403 o->flags &=~ SEC_RELOC;
4404 }
4405
4406 /* If the SEC_ALLOC flag is not set, force the section VMA to
4407 zero. This is done in elf_fake_sections as well, but forcing
4408 the VMA to 0 here will ensure that relocs against these
4409 sections are handled correctly. */
4410 if ((o->flags & SEC_ALLOC) == 0
4411 && ! o->user_set_vma)
4412 o->vma = 0;
4413 }
4414
4415 if (! info->relocateable && merged)
4416 elf_link_hash_traverse (elf_hash_table (info),
4417 elf_link_sec_merge_syms, (PTR) abfd);
4418
4419 /* Figure out the file positions for everything but the symbol table
4420 and the relocs. We set symcount to force assign_section_numbers
4421 to create a symbol table. */
4422 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4423 BFD_ASSERT (! abfd->output_has_begun);
4424 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4425 goto error_return;
4426
4427 /* Figure out how many relocations we will have in each section.
4428 Just using RELOC_COUNT isn't good enough since that doesn't
4429 maintain a separate value for REL vs. RELA relocations. */
4430 if (info->relocateable || info->emitrelocations)
4431 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4432 for (o = sub->sections; o != NULL; o = o->next)
4433 {
4434 asection *output_section;
4435
4436 if (! o->linker_mark)
4437 {
4438 /* This section was omitted from the link. */
4439 continue;
4440 }
4441
4442 output_section = o->output_section;
4443
4444 if (output_section != NULL
4445 && (o->flags & SEC_RELOC) != 0)
4446 {
4447 struct bfd_elf_section_data *esdi
4448 = elf_section_data (o);
4449 struct bfd_elf_section_data *esdo
4450 = elf_section_data (output_section);
4451 unsigned int *rel_count;
4452 unsigned int *rel_count2;
4453
4454 /* We must be careful to add the relocation froms the
4455 input section to the right output count. */
4456 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4457 {
4458 rel_count = &esdo->rel_count;
4459 rel_count2 = &esdo->rel_count2;
4460 }
4461 else
4462 {
4463 rel_count = &esdo->rel_count2;
4464 rel_count2 = &esdo->rel_count;
4465 }
4466
4467 *rel_count += NUM_SHDR_ENTRIES (& esdi->rel_hdr);
4468 if (esdi->rel_hdr2)
4469 *rel_count2 += NUM_SHDR_ENTRIES (esdi->rel_hdr2);
4470 }
4471 }
4472
4473 /* That created the reloc sections. Set their sizes, and assign
4474 them file positions, and allocate some buffers. */
4475 for (o = abfd->sections; o != NULL; o = o->next)
4476 {
4477 if ((o->flags & SEC_RELOC) != 0)
4478 {
4479 if (!elf_link_size_reloc_section (abfd,
4480 &elf_section_data (o)->rel_hdr,
4481 o))
4482 goto error_return;
4483
4484 if (elf_section_data (o)->rel_hdr2
4485 && !elf_link_size_reloc_section (abfd,
4486 elf_section_data (o)->rel_hdr2,
4487 o))
4488 goto error_return;
4489 }
4490
4491 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4492 to count upwards while actually outputting the relocations. */
4493 elf_section_data (o)->rel_count = 0;
4494 elf_section_data (o)->rel_count2 = 0;
4495 }
4496
4497 _bfd_elf_assign_file_positions_for_relocs (abfd);
4498
4499 /* We have now assigned file positions for all the sections except
4500 .symtab and .strtab. We start the .symtab section at the current
4501 file position, and write directly to it. We build the .strtab
4502 section in memory. */
4503 bfd_get_symcount (abfd) = 0;
4504 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4505 /* sh_name is set in prep_headers. */
4506 symtab_hdr->sh_type = SHT_SYMTAB;
4507 symtab_hdr->sh_flags = 0;
4508 symtab_hdr->sh_addr = 0;
4509 symtab_hdr->sh_size = 0;
4510 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4511 /* sh_link is set in assign_section_numbers. */
4512 /* sh_info is set below. */
4513 /* sh_offset is set just below. */
4514 symtab_hdr->sh_addralign = bed->s->file_align;
4515
4516 off = elf_tdata (abfd)->next_file_pos;
4517 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4518
4519 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4520 incorrect. We do not yet know the size of the .symtab section.
4521 We correct next_file_pos below, after we do know the size. */
4522
4523 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4524 continuously seeking to the right position in the file. */
4525 if (! info->keep_memory || max_sym_count < 20)
4526 finfo.symbuf_size = 20;
4527 else
4528 finfo.symbuf_size = max_sym_count;
4529 finfo.symbuf = ((Elf_External_Sym *)
4530 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4531 if (finfo.symbuf == NULL)
4532 goto error_return;
4533
4534 /* Start writing out the symbol table. The first symbol is always a
4535 dummy symbol. */
4536 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4537 {
4538 elfsym.st_value = 0;
4539 elfsym.st_size = 0;
4540 elfsym.st_info = 0;
4541 elfsym.st_other = 0;
4542 elfsym.st_shndx = SHN_UNDEF;
4543 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4544 &elfsym, bfd_und_section_ptr))
4545 goto error_return;
4546 }
4547
4548 #if 0
4549 /* Some standard ELF linkers do this, but we don't because it causes
4550 bootstrap comparison failures. */
4551 /* Output a file symbol for the output file as the second symbol.
4552 We output this even if we are discarding local symbols, although
4553 I'm not sure if this is correct. */
4554 elfsym.st_value = 0;
4555 elfsym.st_size = 0;
4556 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4557 elfsym.st_other = 0;
4558 elfsym.st_shndx = SHN_ABS;
4559 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4560 &elfsym, bfd_abs_section_ptr))
4561 goto error_return;
4562 #endif
4563
4564 /* Output a symbol for each section. We output these even if we are
4565 discarding local symbols, since they are used for relocs. These
4566 symbols have no names. We store the index of each one in the
4567 index field of the section, so that we can find it again when
4568 outputting relocs. */
4569 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4570 {
4571 elfsym.st_size = 0;
4572 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4573 elfsym.st_other = 0;
4574 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4575 {
4576 o = section_from_elf_index (abfd, i);
4577 if (o != NULL)
4578 o->target_index = bfd_get_symcount (abfd);
4579 elfsym.st_shndx = i;
4580 if (info->relocateable || o == NULL)
4581 elfsym.st_value = 0;
4582 else
4583 elfsym.st_value = o->vma;
4584 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4585 &elfsym, o))
4586 goto error_return;
4587 }
4588 }
4589
4590 /* Allocate some memory to hold information read in from the input
4591 files. */
4592 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4593 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4594 finfo.internal_relocs = ((Elf_Internal_Rela *)
4595 bfd_malloc (max_internal_reloc_count
4596 * sizeof (Elf_Internal_Rela)
4597 * bed->s->int_rels_per_ext_rel));
4598 finfo.external_syms = ((Elf_External_Sym *)
4599 bfd_malloc (max_sym_count
4600 * sizeof (Elf_External_Sym)));
4601 finfo.internal_syms = ((Elf_Internal_Sym *)
4602 bfd_malloc (max_sym_count
4603 * sizeof (Elf_Internal_Sym)));
4604 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4605 finfo.sections = ((asection **)
4606 bfd_malloc (max_sym_count * sizeof (asection *)));
4607 if ((finfo.contents == NULL && max_contents_size != 0)
4608 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4609 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4610 || (finfo.external_syms == NULL && max_sym_count != 0)
4611 || (finfo.internal_syms == NULL && max_sym_count != 0)
4612 || (finfo.indices == NULL && max_sym_count != 0)
4613 || (finfo.sections == NULL && max_sym_count != 0))
4614 goto error_return;
4615
4616 /* Since ELF permits relocations to be against local symbols, we
4617 must have the local symbols available when we do the relocations.
4618 Since we would rather only read the local symbols once, and we
4619 would rather not keep them in memory, we handle all the
4620 relocations for a single input file at the same time.
4621
4622 Unfortunately, there is no way to know the total number of local
4623 symbols until we have seen all of them, and the local symbol
4624 indices precede the global symbol indices. This means that when
4625 we are generating relocateable output, and we see a reloc against
4626 a global symbol, we can not know the symbol index until we have
4627 finished examining all the local symbols to see which ones we are
4628 going to output. To deal with this, we keep the relocations in
4629 memory, and don't output them until the end of the link. This is
4630 an unfortunate waste of memory, but I don't see a good way around
4631 it. Fortunately, it only happens when performing a relocateable
4632 link, which is not the common case. FIXME: If keep_memory is set
4633 we could write the relocs out and then read them again; I don't
4634 know how bad the memory loss will be. */
4635
4636 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4637 sub->output_has_begun = false;
4638 for (o = abfd->sections; o != NULL; o = o->next)
4639 {
4640 for (p = o->link_order_head; p != NULL; p = p->next)
4641 {
4642 if (p->type == bfd_indirect_link_order
4643 && (bfd_get_flavour (p->u.indirect.section->owner)
4644 == bfd_target_elf_flavour))
4645 {
4646 sub = p->u.indirect.section->owner;
4647 if (! sub->output_has_begun)
4648 {
4649 if (! elf_link_input_bfd (&finfo, sub))
4650 goto error_return;
4651 sub->output_has_begun = true;
4652 }
4653 }
4654 else if (p->type == bfd_section_reloc_link_order
4655 || p->type == bfd_symbol_reloc_link_order)
4656 {
4657 if (! elf_reloc_link_order (abfd, info, o, p))
4658 goto error_return;
4659 }
4660 else
4661 {
4662 if (! _bfd_default_link_order (abfd, info, o, p))
4663 goto error_return;
4664 }
4665 }
4666 }
4667
4668 /* That wrote out all the local symbols. Finish up the symbol table
4669 with the global symbols. Even if we want to strip everything we
4670 can, we still need to deal with those global symbols that got
4671 converted to local in a version script. */
4672
4673 if (info->shared)
4674 {
4675 /* Output any global symbols that got converted to local in a
4676 version script. We do this in a separate step since ELF
4677 requires all local symbols to appear prior to any global
4678 symbols. FIXME: We should only do this if some global
4679 symbols were, in fact, converted to become local. FIXME:
4680 Will this work correctly with the Irix 5 linker? */
4681 eoinfo.failed = false;
4682 eoinfo.finfo = &finfo;
4683 eoinfo.localsyms = true;
4684 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4685 (PTR) &eoinfo);
4686 if (eoinfo.failed)
4687 return false;
4688 }
4689
4690 /* The sh_info field records the index of the first non local symbol. */
4691 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4692
4693 if (dynamic
4694 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
4695 {
4696 Elf_Internal_Sym sym;
4697 Elf_External_Sym *dynsym =
4698 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4699 long last_local = 0;
4700
4701 /* Write out the section symbols for the output sections. */
4702 if (info->shared)
4703 {
4704 asection *s;
4705
4706 sym.st_size = 0;
4707 sym.st_name = 0;
4708 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4709 sym.st_other = 0;
4710
4711 for (s = abfd->sections; s != NULL; s = s->next)
4712 {
4713 int indx;
4714 indx = elf_section_data (s)->this_idx;
4715 BFD_ASSERT (indx > 0);
4716 sym.st_shndx = indx;
4717 sym.st_value = s->vma;
4718
4719 elf_swap_symbol_out (abfd, &sym,
4720 dynsym + elf_section_data (s)->dynindx);
4721 }
4722
4723 last_local = bfd_count_sections (abfd);
4724 }
4725
4726 /* Write out the local dynsyms. */
4727 if (elf_hash_table (info)->dynlocal)
4728 {
4729 struct elf_link_local_dynamic_entry *e;
4730 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4731 {
4732 asection *s;
4733
4734 sym.st_size = e->isym.st_size;
4735 sym.st_other = e->isym.st_other;
4736
4737 /* Copy the internal symbol as is.
4738 Note that we saved a word of storage and overwrote
4739 the original st_name with the dynstr_index. */
4740 sym = e->isym;
4741
4742 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4743 {
4744 s = bfd_section_from_elf_index (e->input_bfd,
4745 e->isym.st_shndx);
4746
4747 sym.st_shndx =
4748 elf_section_data (s->output_section)->this_idx;
4749 sym.st_value = (s->output_section->vma
4750 + s->output_offset
4751 + e->isym.st_value);
4752 }
4753
4754 if (last_local < e->dynindx)
4755 last_local = e->dynindx;
4756
4757 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4758 }
4759 }
4760
4761 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4762 last_local + 1;
4763 }
4764
4765 /* We get the global symbols from the hash table. */
4766 eoinfo.failed = false;
4767 eoinfo.localsyms = false;
4768 eoinfo.finfo = &finfo;
4769 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4770 (PTR) &eoinfo);
4771 if (eoinfo.failed)
4772 return false;
4773
4774 /* If backend needs to output some symbols not present in the hash
4775 table, do it now. */
4776 if (bed->elf_backend_output_arch_syms)
4777 {
4778 if (! (*bed->elf_backend_output_arch_syms)
4779 (abfd, info, (PTR) &finfo,
4780 (boolean (*) PARAMS ((PTR, const char *,
4781 Elf_Internal_Sym *, asection *)))
4782 elf_link_output_sym))
4783 return false;
4784 }
4785
4786 /* Flush all symbols to the file. */
4787 if (! elf_link_flush_output_syms (&finfo))
4788 return false;
4789
4790 /* Now we know the size of the symtab section. */
4791 off += symtab_hdr->sh_size;
4792
4793 /* Finish up and write out the symbol string table (.strtab)
4794 section. */
4795 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4796 /* sh_name was set in prep_headers. */
4797 symstrtab_hdr->sh_type = SHT_STRTAB;
4798 symstrtab_hdr->sh_flags = 0;
4799 symstrtab_hdr->sh_addr = 0;
4800 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4801 symstrtab_hdr->sh_entsize = 0;
4802 symstrtab_hdr->sh_link = 0;
4803 symstrtab_hdr->sh_info = 0;
4804 /* sh_offset is set just below. */
4805 symstrtab_hdr->sh_addralign = 1;
4806
4807 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4808 elf_tdata (abfd)->next_file_pos = off;
4809
4810 if (bfd_get_symcount (abfd) > 0)
4811 {
4812 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4813 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4814 return false;
4815 }
4816
4817 /* Adjust the relocs to have the correct symbol indices. */
4818 for (o = abfd->sections; o != NULL; o = o->next)
4819 {
4820 if ((o->flags & SEC_RELOC) == 0)
4821 continue;
4822
4823 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4824 elf_section_data (o)->rel_count,
4825 elf_section_data (o)->rel_hashes);
4826 if (elf_section_data (o)->rel_hdr2 != NULL)
4827 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4828 elf_section_data (o)->rel_count2,
4829 (elf_section_data (o)->rel_hashes
4830 + elf_section_data (o)->rel_count));
4831
4832 /* Set the reloc_count field to 0 to prevent write_relocs from
4833 trying to swap the relocs out itself. */
4834 o->reloc_count = 0;
4835 }
4836
4837 /* If we are linking against a dynamic object, or generating a
4838 shared library, finish up the dynamic linking information. */
4839 if (dynamic)
4840 {
4841 Elf_External_Dyn *dyncon, *dynconend;
4842
4843 /* Fix up .dynamic entries. */
4844 o = bfd_get_section_by_name (dynobj, ".dynamic");
4845 BFD_ASSERT (o != NULL);
4846
4847 dyncon = (Elf_External_Dyn *) o->contents;
4848 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4849 for (; dyncon < dynconend; dyncon++)
4850 {
4851 Elf_Internal_Dyn dyn;
4852 const char *name;
4853 unsigned int type;
4854
4855 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4856
4857 switch (dyn.d_tag)
4858 {
4859 default:
4860 break;
4861 case DT_INIT:
4862 name = info->init_function;
4863 goto get_sym;
4864 case DT_FINI:
4865 name = info->fini_function;
4866 get_sym:
4867 {
4868 struct elf_link_hash_entry *h;
4869
4870 h = elf_link_hash_lookup (elf_hash_table (info), name,
4871 false, false, true);
4872 if (h != NULL
4873 && (h->root.type == bfd_link_hash_defined
4874 || h->root.type == bfd_link_hash_defweak))
4875 {
4876 dyn.d_un.d_val = h->root.u.def.value;
4877 o = h->root.u.def.section;
4878 if (o->output_section != NULL)
4879 dyn.d_un.d_val += (o->output_section->vma
4880 + o->output_offset);
4881 else
4882 {
4883 /* The symbol is imported from another shared
4884 library and does not apply to this one. */
4885 dyn.d_un.d_val = 0;
4886 }
4887
4888 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4889 }
4890 }
4891 break;
4892
4893 case DT_HASH:
4894 name = ".hash";
4895 goto get_vma;
4896 case DT_STRTAB:
4897 name = ".dynstr";
4898 goto get_vma;
4899 case DT_SYMTAB:
4900 name = ".dynsym";
4901 goto get_vma;
4902 case DT_VERDEF:
4903 name = ".gnu.version_d";
4904 goto get_vma;
4905 case DT_VERNEED:
4906 name = ".gnu.version_r";
4907 goto get_vma;
4908 case DT_VERSYM:
4909 name = ".gnu.version";
4910 get_vma:
4911 o = bfd_get_section_by_name (abfd, name);
4912 BFD_ASSERT (o != NULL);
4913 dyn.d_un.d_ptr = o->vma;
4914 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4915 break;
4916
4917 case DT_REL:
4918 case DT_RELA:
4919 case DT_RELSZ:
4920 case DT_RELASZ:
4921 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4922 type = SHT_REL;
4923 else
4924 type = SHT_RELA;
4925 dyn.d_un.d_val = 0;
4926 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4927 {
4928 Elf_Internal_Shdr *hdr;
4929
4930 hdr = elf_elfsections (abfd)[i];
4931 if (hdr->sh_type == type
4932 && (hdr->sh_flags & SHF_ALLOC) != 0)
4933 {
4934 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4935 dyn.d_un.d_val += hdr->sh_size;
4936 else
4937 {
4938 if (dyn.d_un.d_val == 0
4939 || hdr->sh_addr < dyn.d_un.d_val)
4940 dyn.d_un.d_val = hdr->sh_addr;
4941 }
4942 }
4943 }
4944 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4945 break;
4946 }
4947 }
4948 }
4949
4950 /* If we have created any dynamic sections, then output them. */
4951 if (dynobj != NULL)
4952 {
4953 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4954 goto error_return;
4955
4956 for (o = dynobj->sections; o != NULL; o = o->next)
4957 {
4958 if ((o->flags & SEC_HAS_CONTENTS) == 0
4959 || o->_raw_size == 0
4960 || o->output_section == bfd_abs_section_ptr)
4961 continue;
4962 if ((o->flags & SEC_LINKER_CREATED) == 0)
4963 {
4964 /* At this point, we are only interested in sections
4965 created by elf_link_create_dynamic_sections. */
4966 continue;
4967 }
4968 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4969 != SHT_STRTAB)
4970 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4971 {
4972 if (! bfd_set_section_contents (abfd, o->output_section,
4973 o->contents, o->output_offset,
4974 o->_raw_size))
4975 goto error_return;
4976 }
4977 else
4978 {
4979 file_ptr off;
4980
4981 /* The contents of the .dynstr section are actually in a
4982 stringtab. */
4983 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4984 if (bfd_seek (abfd, off, SEEK_SET) != 0
4985 || ! _bfd_stringtab_emit (abfd,
4986 elf_hash_table (info)->dynstr))
4987 goto error_return;
4988 }
4989 }
4990 }
4991
4992 /* If we have optimized stabs strings, output them. */
4993 if (elf_hash_table (info)->stab_info != NULL)
4994 {
4995 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4996 goto error_return;
4997 }
4998
4999 if (finfo.symstrtab != NULL)
5000 _bfd_stringtab_free (finfo.symstrtab);
5001 if (finfo.contents != NULL)
5002 free (finfo.contents);
5003 if (finfo.external_relocs != NULL)
5004 free (finfo.external_relocs);
5005 if (finfo.internal_relocs != NULL)
5006 free (finfo.internal_relocs);
5007 if (finfo.external_syms != NULL)
5008 free (finfo.external_syms);
5009 if (finfo.internal_syms != NULL)
5010 free (finfo.internal_syms);
5011 if (finfo.indices != NULL)
5012 free (finfo.indices);
5013 if (finfo.sections != NULL)
5014 free (finfo.sections);
5015 if (finfo.symbuf != NULL)
5016 free (finfo.symbuf);
5017 for (o = abfd->sections; o != NULL; o = o->next)
5018 {
5019 if ((o->flags & SEC_RELOC) != 0
5020 && elf_section_data (o)->rel_hashes != NULL)
5021 free (elf_section_data (o)->rel_hashes);
5022 }
5023
5024 elf_tdata (abfd)->linker = true;
5025
5026 return true;
5027
5028 error_return:
5029 if (finfo.symstrtab != NULL)
5030 _bfd_stringtab_free (finfo.symstrtab);
5031 if (finfo.contents != NULL)
5032 free (finfo.contents);
5033 if (finfo.external_relocs != NULL)
5034 free (finfo.external_relocs);
5035 if (finfo.internal_relocs != NULL)
5036 free (finfo.internal_relocs);
5037 if (finfo.external_syms != NULL)
5038 free (finfo.external_syms);
5039 if (finfo.internal_syms != NULL)
5040 free (finfo.internal_syms);
5041 if (finfo.indices != NULL)
5042 free (finfo.indices);
5043 if (finfo.sections != NULL)
5044 free (finfo.sections);
5045 if (finfo.symbuf != NULL)
5046 free (finfo.symbuf);
5047 for (o = abfd->sections; o != NULL; o = o->next)
5048 {
5049 if ((o->flags & SEC_RELOC) != 0
5050 && elf_section_data (o)->rel_hashes != NULL)
5051 free (elf_section_data (o)->rel_hashes);
5052 }
5053
5054 return false;
5055 }
5056
5057 /* Add a symbol to the output symbol table. */
5058
5059 static boolean
5060 elf_link_output_sym (finfo, name, elfsym, input_sec)
5061 struct elf_final_link_info *finfo;
5062 const char *name;
5063 Elf_Internal_Sym *elfsym;
5064 asection *input_sec;
5065 {
5066 boolean (*output_symbol_hook) PARAMS ((bfd *,
5067 struct bfd_link_info *info,
5068 const char *,
5069 Elf_Internal_Sym *,
5070 asection *));
5071
5072 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
5073 elf_backend_link_output_symbol_hook;
5074 if (output_symbol_hook != NULL)
5075 {
5076 if (! ((*output_symbol_hook)
5077 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
5078 return false;
5079 }
5080
5081 if (name == (const char *) NULL || *name == '\0')
5082 elfsym->st_name = 0;
5083 else if (input_sec->flags & SEC_EXCLUDE)
5084 elfsym->st_name = 0;
5085 else
5086 {
5087 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5088 name, true,
5089 false);
5090 if (elfsym->st_name == (unsigned long) -1)
5091 return false;
5092 }
5093
5094 if (finfo->symbuf_count >= finfo->symbuf_size)
5095 {
5096 if (! elf_link_flush_output_syms (finfo))
5097 return false;
5098 }
5099
5100 elf_swap_symbol_out (finfo->output_bfd, elfsym,
5101 (PTR) (finfo->symbuf + finfo->symbuf_count));
5102 ++finfo->symbuf_count;
5103
5104 ++ bfd_get_symcount (finfo->output_bfd);
5105
5106 return true;
5107 }
5108
5109 /* Flush the output symbols to the file. */
5110
5111 static boolean
5112 elf_link_flush_output_syms (finfo)
5113 struct elf_final_link_info *finfo;
5114 {
5115 if (finfo->symbuf_count > 0)
5116 {
5117 Elf_Internal_Shdr *symtab;
5118
5119 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5120
5121 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
5122 SEEK_SET) != 0
5123 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
5124 sizeof (Elf_External_Sym), finfo->output_bfd)
5125 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
5126 return false;
5127
5128 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
5129
5130 finfo->symbuf_count = 0;
5131 }
5132
5133 return true;
5134 }
5135
5136 /* Adjust all external symbols pointing into SEC_MERGE sections
5137 to reflect the object merging within the sections. */
5138
5139 static boolean
5140 elf_link_sec_merge_syms (h, data)
5141 struct elf_link_hash_entry *h;
5142 PTR data;
5143 {
5144 asection *sec;
5145
5146 if ((h->root.type == bfd_link_hash_defined
5147 || h->root.type == bfd_link_hash_defweak)
5148 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
5149 && elf_section_data (sec)->merge_info)
5150 {
5151 bfd *output_bfd = (bfd *) data;
5152
5153 h->root.u.def.value =
5154 _bfd_merged_section_offset (output_bfd,
5155 &h->root.u.def.section,
5156 elf_section_data (sec)->merge_info,
5157 h->root.u.def.value, (bfd_vma) 0);
5158 }
5159
5160 return true;
5161 }
5162
5163 /* Add an external symbol to the symbol table. This is called from
5164 the hash table traversal routine. When generating a shared object,
5165 we go through the symbol table twice. The first time we output
5166 anything that might have been forced to local scope in a version
5167 script. The second time we output the symbols that are still
5168 global symbols. */
5169
5170 static boolean
5171 elf_link_output_extsym (h, data)
5172 struct elf_link_hash_entry *h;
5173 PTR data;
5174 {
5175 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
5176 struct elf_final_link_info *finfo = eoinfo->finfo;
5177 boolean strip;
5178 Elf_Internal_Sym sym;
5179 asection *input_sec;
5180
5181 /* Decide whether to output this symbol in this pass. */
5182 if (eoinfo->localsyms)
5183 {
5184 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5185 return true;
5186 }
5187 else
5188 {
5189 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5190 return true;
5191 }
5192
5193 /* If we are not creating a shared library, and this symbol is
5194 referenced by a shared library but is not defined anywhere, then
5195 warn that it is undefined. If we do not do this, the runtime
5196 linker will complain that the symbol is undefined when the
5197 program is run. We don't have to worry about symbols that are
5198 referenced by regular files, because we will already have issued
5199 warnings for them. */
5200 if (! finfo->info->relocateable
5201 && ! finfo->info->allow_shlib_undefined
5202 && ! (finfo->info->shared
5203 && !finfo->info->no_undefined)
5204 && h->root.type == bfd_link_hash_undefined
5205 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
5206 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5207 {
5208 if (! ((*finfo->info->callbacks->undefined_symbol)
5209 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
5210 (asection *) NULL, 0, true)))
5211 {
5212 eoinfo->failed = true;
5213 return false;
5214 }
5215 }
5216
5217 /* We don't want to output symbols that have never been mentioned by
5218 a regular file, or that we have been told to strip. However, if
5219 h->indx is set to -2, the symbol is used by a reloc and we must
5220 output it. */
5221 if (h->indx == -2)
5222 strip = false;
5223 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
5224 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
5225 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
5226 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5227 strip = true;
5228 else if (finfo->info->strip == strip_all
5229 || (finfo->info->strip == strip_some
5230 && bfd_hash_lookup (finfo->info->keep_hash,
5231 h->root.root.string,
5232 false, false) == NULL))
5233 strip = true;
5234 else
5235 strip = false;
5236
5237 /* If we're stripping it, and it's not a dynamic symbol, there's
5238 nothing else to do unless it is a forced local symbol. */
5239 if (strip
5240 && h->dynindx == -1
5241 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5242 return true;
5243
5244 sym.st_value = 0;
5245 sym.st_size = h->size;
5246 sym.st_other = h->other;
5247 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5248 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5249 else if (h->root.type == bfd_link_hash_undefweak
5250 || h->root.type == bfd_link_hash_defweak)
5251 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5252 else
5253 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5254
5255 switch (h->root.type)
5256 {
5257 default:
5258 case bfd_link_hash_new:
5259 abort ();
5260 return false;
5261
5262 case bfd_link_hash_undefined:
5263 input_sec = bfd_und_section_ptr;
5264 sym.st_shndx = SHN_UNDEF;
5265 break;
5266
5267 case bfd_link_hash_undefweak:
5268 input_sec = bfd_und_section_ptr;
5269 sym.st_shndx = SHN_UNDEF;
5270 break;
5271
5272 case bfd_link_hash_defined:
5273 case bfd_link_hash_defweak:
5274 {
5275 input_sec = h->root.u.def.section;
5276 if (input_sec->output_section != NULL)
5277 {
5278 sym.st_shndx =
5279 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5280 input_sec->output_section);
5281 if (sym.st_shndx == (unsigned short) -1)
5282 {
5283 (*_bfd_error_handler)
5284 (_("%s: could not find output section %s for input section %s"),
5285 bfd_get_filename (finfo->output_bfd),
5286 input_sec->output_section->name,
5287 input_sec->name);
5288 eoinfo->failed = true;
5289 return false;
5290 }
5291
5292 /* ELF symbols in relocateable files are section relative,
5293 but in nonrelocateable files they are virtual
5294 addresses. */
5295 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5296 if (! finfo->info->relocateable)
5297 sym.st_value += input_sec->output_section->vma;
5298 }
5299 else
5300 {
5301 BFD_ASSERT (input_sec->owner == NULL
5302 || (input_sec->owner->flags & DYNAMIC) != 0);
5303 sym.st_shndx = SHN_UNDEF;
5304 input_sec = bfd_und_section_ptr;
5305 }
5306 }
5307 break;
5308
5309 case bfd_link_hash_common:
5310 input_sec = h->root.u.c.p->section;
5311 sym.st_shndx = SHN_COMMON;
5312 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5313 break;
5314
5315 case bfd_link_hash_indirect:
5316 /* These symbols are created by symbol versioning. They point
5317 to the decorated version of the name. For example, if the
5318 symbol foo@@GNU_1.2 is the default, which should be used when
5319 foo is used with no version, then we add an indirect symbol
5320 foo which points to foo@@GNU_1.2. We ignore these symbols,
5321 since the indirected symbol is already in the hash table. */
5322 return true;
5323
5324 case bfd_link_hash_warning:
5325 /* We can't represent these symbols in ELF, although a warning
5326 symbol may have come from a .gnu.warning.SYMBOL section. We
5327 just put the target symbol in the hash table. If the target
5328 symbol does not really exist, don't do anything. */
5329 if (h->root.u.i.link->type == bfd_link_hash_new)
5330 return true;
5331 return (elf_link_output_extsym
5332 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5333 }
5334
5335 /* Give the processor backend a chance to tweak the symbol value,
5336 and also to finish up anything that needs to be done for this
5337 symbol. */
5338 if ((h->dynindx != -1
5339 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5340 && elf_hash_table (finfo->info)->dynamic_sections_created)
5341 {
5342 struct elf_backend_data *bed;
5343
5344 bed = get_elf_backend_data (finfo->output_bfd);
5345 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5346 (finfo->output_bfd, finfo->info, h, &sym)))
5347 {
5348 eoinfo->failed = true;
5349 return false;
5350 }
5351 }
5352
5353 /* If we are marking the symbol as undefined, and there are no
5354 non-weak references to this symbol from a regular object, then
5355 mark the symbol as weak undefined; if there are non-weak
5356 references, mark the symbol as strong. We can't do this earlier,
5357 because it might not be marked as undefined until the
5358 finish_dynamic_symbol routine gets through with it. */
5359 if (sym.st_shndx == SHN_UNDEF
5360 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5361 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5362 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5363 {
5364 int bindtype;
5365
5366 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5367 bindtype = STB_GLOBAL;
5368 else
5369 bindtype = STB_WEAK;
5370 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5371 }
5372
5373 /* If a symbol is not defined locally, we clear the visibility
5374 field. */
5375 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5376 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5377
5378 /* If this symbol should be put in the .dynsym section, then put it
5379 there now. We have already know the symbol index. We also fill
5380 in the entry in the .hash section. */
5381 if (h->dynindx != -1
5382 && elf_hash_table (finfo->info)->dynamic_sections_created)
5383 {
5384 size_t bucketcount;
5385 size_t bucket;
5386 size_t hash_entry_size;
5387 bfd_byte *bucketpos;
5388 bfd_vma chain;
5389
5390 sym.st_name = h->dynstr_index;
5391
5392 elf_swap_symbol_out (finfo->output_bfd, &sym,
5393 (PTR) (((Elf_External_Sym *)
5394 finfo->dynsym_sec->contents)
5395 + h->dynindx));
5396
5397 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5398 bucket = h->elf_hash_value % bucketcount;
5399 hash_entry_size
5400 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5401 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5402 + (bucket + 2) * hash_entry_size);
5403 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5404 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5405 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5406 ((bfd_byte *) finfo->hash_sec->contents
5407 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5408
5409 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5410 {
5411 Elf_Internal_Versym iversym;
5412
5413 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5414 {
5415 if (h->verinfo.verdef == NULL)
5416 iversym.vs_vers = 0;
5417 else
5418 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5419 }
5420 else
5421 {
5422 if (h->verinfo.vertree == NULL)
5423 iversym.vs_vers = 1;
5424 else
5425 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5426 }
5427
5428 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5429 iversym.vs_vers |= VERSYM_HIDDEN;
5430
5431 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5432 (((Elf_External_Versym *)
5433 finfo->symver_sec->contents)
5434 + h->dynindx));
5435 }
5436 }
5437
5438 /* If we're stripping it, then it was just a dynamic symbol, and
5439 there's nothing else to do. */
5440 if (strip)
5441 return true;
5442
5443 h->indx = bfd_get_symcount (finfo->output_bfd);
5444
5445 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5446 {
5447 eoinfo->failed = true;
5448 return false;
5449 }
5450
5451 return true;
5452 }
5453
5454 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5455 originated from the section given by INPUT_REL_HDR) to the
5456 OUTPUT_BFD. */
5457
5458 static void
5459 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5460 internal_relocs)
5461 bfd *output_bfd;
5462 asection *input_section;
5463 Elf_Internal_Shdr *input_rel_hdr;
5464 Elf_Internal_Rela *internal_relocs;
5465 {
5466 Elf_Internal_Rela *irela;
5467 Elf_Internal_Rela *irelaend;
5468 Elf_Internal_Shdr *output_rel_hdr;
5469 asection *output_section;
5470 unsigned int *rel_countp = NULL;
5471 struct elf_backend_data *bed;
5472
5473 output_section = input_section->output_section;
5474 output_rel_hdr = NULL;
5475
5476 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5477 == input_rel_hdr->sh_entsize)
5478 {
5479 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5480 rel_countp = &elf_section_data (output_section)->rel_count;
5481 }
5482 else if (elf_section_data (output_section)->rel_hdr2
5483 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5484 == input_rel_hdr->sh_entsize))
5485 {
5486 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5487 rel_countp = &elf_section_data (output_section)->rel_count2;
5488 }
5489
5490 BFD_ASSERT (output_rel_hdr != NULL);
5491
5492 bed = get_elf_backend_data (output_bfd);
5493 irela = internal_relocs;
5494 irelaend = irela + NUM_SHDR_ENTRIES (input_rel_hdr)
5495 * bed->s->int_rels_per_ext_rel;
5496
5497 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5498 {
5499 Elf_External_Rel *erel;
5500 Elf_Internal_Rel *irel;
5501
5502 irel = (Elf_Internal_Rel *) bfd_zmalloc (bed->s->int_rels_per_ext_rel
5503 * sizeof (Elf_Internal_Rel));
5504 if (irel == NULL)
5505 {
5506 (*_bfd_error_handler) (_("Error: out of memory"));
5507 abort ();
5508 }
5509
5510 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5511 for (; irela < irelaend; irela += bed->s->int_rels_per_ext_rel, erel++)
5512 {
5513 unsigned int i;
5514
5515 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
5516 {
5517 irel[i].r_offset = irela[i].r_offset;
5518 irel[i].r_info = irela[i].r_info;
5519 BFD_ASSERT (irela[i].r_addend == 0);
5520 }
5521
5522 if (bed->s->swap_reloc_out)
5523 (*bed->s->swap_reloc_out) (output_bfd, irel, (PTR) erel);
5524 else
5525 elf_swap_reloc_out (output_bfd, irel, erel);
5526 }
5527
5528 free (irel);
5529 }
5530 else
5531 {
5532 Elf_External_Rela *erela;
5533
5534 BFD_ASSERT (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rela));
5535
5536 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5537 for (; irela < irelaend; irela += bed->s->int_rels_per_ext_rel, erela++)
5538 if (bed->s->swap_reloca_out)
5539 (*bed->s->swap_reloca_out) (output_bfd, irela, (PTR) erela);
5540 else
5541 elf_swap_reloca_out (output_bfd, irela, erela);
5542 }
5543
5544 /* Bump the counter, so that we know where to add the next set of
5545 relocations. */
5546 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
5547 }
5548
5549 /* Link an input file into the linker output file. This function
5550 handles all the sections and relocations of the input file at once.
5551 This is so that we only have to read the local symbols once, and
5552 don't have to keep them in memory. */
5553
5554 static boolean
5555 elf_link_input_bfd (finfo, input_bfd)
5556 struct elf_final_link_info *finfo;
5557 bfd *input_bfd;
5558 {
5559 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5560 bfd *, asection *, bfd_byte *,
5561 Elf_Internal_Rela *,
5562 Elf_Internal_Sym *, asection **));
5563 bfd *output_bfd;
5564 Elf_Internal_Shdr *symtab_hdr;
5565 size_t locsymcount;
5566 size_t extsymoff;
5567 Elf_External_Sym *external_syms;
5568 Elf_External_Sym *esym;
5569 Elf_External_Sym *esymend;
5570 Elf_Internal_Sym *isym;
5571 long *pindex;
5572 asection **ppsection;
5573 asection *o;
5574 struct elf_backend_data *bed;
5575
5576 output_bfd = finfo->output_bfd;
5577 bed = get_elf_backend_data (output_bfd);
5578 relocate_section = bed->elf_backend_relocate_section;
5579
5580 /* If this is a dynamic object, we don't want to do anything here:
5581 we don't want the local symbols, and we don't want the section
5582 contents. */
5583 if ((input_bfd->flags & DYNAMIC) != 0)
5584 return true;
5585
5586 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5587 if (elf_bad_symtab (input_bfd))
5588 {
5589 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5590 extsymoff = 0;
5591 }
5592 else
5593 {
5594 locsymcount = symtab_hdr->sh_info;
5595 extsymoff = symtab_hdr->sh_info;
5596 }
5597
5598 /* Read the local symbols. */
5599 if (symtab_hdr->contents != NULL)
5600 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5601 else if (locsymcount == 0)
5602 external_syms = NULL;
5603 else
5604 {
5605 external_syms = finfo->external_syms;
5606 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5607 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5608 locsymcount, input_bfd)
5609 != locsymcount * sizeof (Elf_External_Sym)))
5610 return false;
5611 }
5612
5613 /* Swap in the local symbols and write out the ones which we know
5614 are going into the output file. */
5615 esym = external_syms;
5616 esymend = esym + locsymcount;
5617 isym = finfo->internal_syms;
5618 pindex = finfo->indices;
5619 ppsection = finfo->sections;
5620 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5621 {
5622 asection *isec;
5623 const char *name;
5624 Elf_Internal_Sym osym;
5625
5626 elf_swap_symbol_in (input_bfd, esym, isym);
5627 *pindex = -1;
5628
5629 if (elf_bad_symtab (input_bfd))
5630 {
5631 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5632 {
5633 *ppsection = NULL;
5634 continue;
5635 }
5636 }
5637
5638 name = NULL;
5639 if (isym->st_shndx == SHN_UNDEF)
5640 {
5641 isec = bfd_und_section_ptr;
5642 name = isec->name;
5643 }
5644 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5645 {
5646 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5647 if (isec && elf_section_data (isec)->merge_info
5648 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
5649 isym->st_value =
5650 _bfd_merged_section_offset (output_bfd, &isec,
5651 elf_section_data (isec)->merge_info,
5652 isym->st_value, (bfd_vma) 0);
5653 }
5654 else if (isym->st_shndx == SHN_ABS)
5655 {
5656 isec = bfd_abs_section_ptr;
5657 name = isec->name;
5658 }
5659 else if (isym->st_shndx == SHN_COMMON)
5660 {
5661 isec = bfd_com_section_ptr;
5662 name = isec->name;
5663 }
5664 else
5665 {
5666 /* Who knows? */
5667 isec = NULL;
5668 }
5669
5670 *ppsection = isec;
5671
5672 /* Don't output the first, undefined, symbol. */
5673 if (esym == external_syms)
5674 continue;
5675
5676 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5677 {
5678 asection *ksec;
5679
5680 /* Save away all section symbol values. */
5681 if (isec != NULL)
5682 {
5683 if (name)
5684 {
5685 if (isec->symbol->value != isym->st_value)
5686 (*_bfd_error_handler)
5687 (_("%s: invalid section symbol index 0x%x (%s) ingored"),
5688 bfd_get_filename (input_bfd), isym->st_shndx,
5689 name);
5690 continue;
5691 }
5692 isec->symbol->value = isym->st_value;
5693 }
5694
5695 /* If this is a discarded link-once section symbol, update
5696 it's value to that of the kept section symbol. The
5697 linker will keep the first of any matching link-once
5698 sections, so we should have already seen it's section
5699 symbol. I trust no-one will have the bright idea of
5700 re-ordering the bfd list... */
5701 if (isec != NULL
5702 && (bfd_get_section_flags (input_bfd, isec) & SEC_LINK_ONCE) != 0
5703 && (ksec = isec->kept_section) != NULL)
5704 {
5705 isym->st_value = ksec->symbol->value;
5706
5707 /* That put the value right, but the section info is all
5708 wrong. I hope this works. */
5709 isec->output_offset = ksec->output_offset;
5710 isec->output_section = ksec->output_section;
5711 }
5712
5713 /* We never output section symbols. Instead, we use the
5714 section symbol of the corresponding section in the output
5715 file. */
5716 continue;
5717 }
5718
5719 /* If we are stripping all symbols, we don't want to output this
5720 one. */
5721 if (finfo->info->strip == strip_all)
5722 continue;
5723
5724 /* If we are discarding all local symbols, we don't want to
5725 output this one. If we are generating a relocateable output
5726 file, then some of the local symbols may be required by
5727 relocs; we output them below as we discover that they are
5728 needed. */
5729 if (finfo->info->discard == discard_all)
5730 continue;
5731
5732 /* If this symbol is defined in a section which we are
5733 discarding, we don't need to keep it, but note that
5734 linker_mark is only reliable for sections that have contents.
5735 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5736 as well as linker_mark. */
5737 if (isym->st_shndx > 0
5738 && isym->st_shndx < SHN_LORESERVE
5739 && isec != NULL
5740 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5741 || (! finfo->info->relocateable
5742 && (isec->flags & SEC_EXCLUDE) != 0)))
5743 continue;
5744
5745 /* Get the name of the symbol. */
5746 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5747 isym->st_name);
5748 if (name == NULL)
5749 return false;
5750
5751 /* See if we are discarding symbols with this name. */
5752 if ((finfo->info->strip == strip_some
5753 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5754 == NULL))
5755 || (((finfo->info->discard == discard_sec_merge
5756 && (isec->flags & SEC_MERGE) && ! finfo->info->relocateable)
5757 || finfo->info->discard == discard_l)
5758 && bfd_is_local_label_name (input_bfd, name)))
5759 continue;
5760
5761 /* If we get here, we are going to output this symbol. */
5762
5763 osym = *isym;
5764
5765 /* Adjust the section index for the output file. */
5766 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5767 isec->output_section);
5768 if (osym.st_shndx == (unsigned short) -1)
5769 return false;
5770
5771 *pindex = bfd_get_symcount (output_bfd);
5772
5773 /* ELF symbols in relocateable files are section relative, but
5774 in executable files they are virtual addresses. Note that
5775 this code assumes that all ELF sections have an associated
5776 BFD section with a reasonable value for output_offset; below
5777 we assume that they also have a reasonable value for
5778 output_section. Any special sections must be set up to meet
5779 these requirements. */
5780 osym.st_value += isec->output_offset;
5781 if (! finfo->info->relocateable)
5782 osym.st_value += isec->output_section->vma;
5783
5784 if (! elf_link_output_sym (finfo, name, &osym, isec))
5785 return false;
5786 }
5787
5788 /* Relocate the contents of each section. */
5789 for (o = input_bfd->sections; o != NULL; o = o->next)
5790 {
5791 bfd_byte *contents;
5792
5793 if (! o->linker_mark)
5794 {
5795 /* This section was omitted from the link. */
5796 continue;
5797 }
5798
5799 if ((o->flags & SEC_HAS_CONTENTS) == 0
5800 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5801 continue;
5802
5803 if ((o->flags & SEC_LINKER_CREATED) != 0)
5804 {
5805 /* Section was created by elf_link_create_dynamic_sections
5806 or somesuch. */
5807 continue;
5808 }
5809
5810 /* Get the contents of the section. They have been cached by a
5811 relaxation routine. Note that o is a section in an input
5812 file, so the contents field will not have been set by any of
5813 the routines which work on output files. */
5814 if (elf_section_data (o)->this_hdr.contents != NULL)
5815 contents = elf_section_data (o)->this_hdr.contents;
5816 else
5817 {
5818 contents = finfo->contents;
5819 if (! bfd_get_section_contents (input_bfd, o, contents,
5820 (file_ptr) 0, o->_raw_size))
5821 return false;
5822 }
5823
5824 if ((o->flags & SEC_RELOC) != 0)
5825 {
5826 Elf_Internal_Rela *internal_relocs;
5827
5828 /* Get the swapped relocs. */
5829 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5830 (input_bfd, o, finfo->external_relocs,
5831 finfo->internal_relocs, false));
5832 if (internal_relocs == NULL
5833 && o->reloc_count > 0)
5834 return false;
5835
5836 /* Relocate the section by invoking a back end routine.
5837
5838 The back end routine is responsible for adjusting the
5839 section contents as necessary, and (if using Rela relocs
5840 and generating a relocateable output file) adjusting the
5841 reloc addend as necessary.
5842
5843 The back end routine does not have to worry about setting
5844 the reloc address or the reloc symbol index.
5845
5846 The back end routine is given a pointer to the swapped in
5847 internal symbols, and can access the hash table entries
5848 for the external symbols via elf_sym_hashes (input_bfd).
5849
5850 When generating relocateable output, the back end routine
5851 must handle STB_LOCAL/STT_SECTION symbols specially. The
5852 output symbol is going to be a section symbol
5853 corresponding to the output section, which will require
5854 the addend to be adjusted. */
5855
5856 if (! (*relocate_section) (output_bfd, finfo->info,
5857 input_bfd, o, contents,
5858 internal_relocs,
5859 finfo->internal_syms,
5860 finfo->sections))
5861 return false;
5862
5863 if (finfo->info->relocateable || finfo->info->emitrelocations)
5864 {
5865 Elf_Internal_Rela *irela;
5866 Elf_Internal_Rela *irelaend;
5867 struct elf_link_hash_entry **rel_hash;
5868 Elf_Internal_Shdr *input_rel_hdr;
5869 unsigned int next_erel;
5870
5871 /* Adjust the reloc addresses and symbol indices. */
5872
5873 irela = internal_relocs;
5874 irelaend = irela
5875 + o->reloc_count * bed->s->int_rels_per_ext_rel;
5876 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5877 + elf_section_data (o->output_section)->rel_count
5878 + elf_section_data (o->output_section)->rel_count2);
5879 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
5880 {
5881 unsigned long r_symndx;
5882 Elf_Internal_Sym *isym;
5883 asection *sec;
5884
5885 if (next_erel == bed->s->int_rels_per_ext_rel)
5886 {
5887 rel_hash++;
5888 next_erel = 0;
5889 }
5890
5891 irela->r_offset += o->output_offset;
5892
5893 /* Relocs in an executable have to be virtual addresses. */
5894 if (finfo->info->emitrelocations)
5895 irela->r_offset += o->output_section->vma;
5896
5897 r_symndx = ELF_R_SYM (irela->r_info);
5898
5899 if (r_symndx == 0)
5900 continue;
5901
5902 if (r_symndx >= locsymcount
5903 || (elf_bad_symtab (input_bfd)
5904 && finfo->sections[r_symndx] == NULL))
5905 {
5906 struct elf_link_hash_entry *rh;
5907 unsigned long indx;
5908
5909 /* This is a reloc against a global symbol. We
5910 have not yet output all the local symbols, so
5911 we do not know the symbol index of any global
5912 symbol. We set the rel_hash entry for this
5913 reloc to point to the global hash table entry
5914 for this symbol. The symbol index is then
5915 set at the end of elf_bfd_final_link. */
5916 indx = r_symndx - extsymoff;
5917 rh = elf_sym_hashes (input_bfd)[indx];
5918 while (rh->root.type == bfd_link_hash_indirect
5919 || rh->root.type == bfd_link_hash_warning)
5920 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5921
5922 /* Setting the index to -2 tells
5923 elf_link_output_extsym that this symbol is
5924 used by a reloc. */
5925 BFD_ASSERT (rh->indx < 0);
5926 rh->indx = -2;
5927
5928 *rel_hash = rh;
5929
5930 continue;
5931 }
5932
5933 /* This is a reloc against a local symbol. */
5934
5935 *rel_hash = NULL;
5936 isym = finfo->internal_syms + r_symndx;
5937 sec = finfo->sections[r_symndx];
5938 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5939 {
5940 /* I suppose the backend ought to fill in the
5941 section of any STT_SECTION symbol against a
5942 processor specific section. If we have
5943 discarded a section, the output_section will
5944 be the absolute section. */
5945 if (sec != NULL
5946 && (bfd_is_abs_section (sec)
5947 || (sec->output_section != NULL
5948 && bfd_is_abs_section (sec->output_section))))
5949 r_symndx = 0;
5950 else if (sec == NULL || sec->owner == NULL)
5951 {
5952 bfd_set_error (bfd_error_bad_value);
5953 return false;
5954 }
5955 else
5956 {
5957 r_symndx = sec->output_section->target_index;
5958 BFD_ASSERT (r_symndx != 0);
5959 }
5960 }
5961 else
5962 {
5963 if (finfo->indices[r_symndx] == -1)
5964 {
5965 unsigned long link;
5966 const char *name;
5967 asection *osec;
5968
5969 if (finfo->info->strip == strip_all)
5970 {
5971 /* You can't do ld -r -s. */
5972 bfd_set_error (bfd_error_invalid_operation);
5973 return false;
5974 }
5975
5976 /* This symbol was skipped earlier, but
5977 since it is needed by a reloc, we
5978 must output it now. */
5979 link = symtab_hdr->sh_link;
5980 name = bfd_elf_string_from_elf_section (input_bfd,
5981 link,
5982 isym->st_name);
5983 if (name == NULL)
5984 return false;
5985
5986 osec = sec->output_section;
5987 isym->st_shndx =
5988 _bfd_elf_section_from_bfd_section (output_bfd,
5989 osec);
5990 if (isym->st_shndx == (unsigned short) -1)
5991 return false;
5992
5993 isym->st_value += sec->output_offset;
5994 if (! finfo->info->relocateable)
5995 isym->st_value += osec->vma;
5996
5997 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5998
5999 if (! elf_link_output_sym (finfo, name, isym, sec))
6000 return false;
6001 }
6002
6003 r_symndx = finfo->indices[r_symndx];
6004 }
6005
6006 irela->r_info = ELF_R_INFO (r_symndx,
6007 ELF_R_TYPE (irela->r_info));
6008 }
6009
6010 /* Swap out the relocs. */
6011 input_rel_hdr = &elf_section_data (o)->rel_hdr;
6012 elf_link_output_relocs (output_bfd, o,
6013 input_rel_hdr,
6014 internal_relocs);
6015 internal_relocs += NUM_SHDR_ENTRIES (input_rel_hdr)
6016 * bed->s->int_rels_per_ext_rel;
6017 input_rel_hdr = elf_section_data (o)->rel_hdr2;
6018 if (input_rel_hdr)
6019 elf_link_output_relocs (output_bfd, o,
6020 input_rel_hdr,
6021 internal_relocs);
6022 }
6023 }
6024
6025 /* Write out the modified section contents. */
6026 if (elf_section_data (o)->stab_info)
6027 {
6028 if (! (_bfd_write_section_stabs
6029 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
6030 o, &elf_section_data (o)->stab_info, contents)))
6031 return false;
6032 }
6033 else if (elf_section_data (o)->merge_info)
6034 {
6035 if (! (_bfd_write_merged_section
6036 (output_bfd, o, elf_section_data (o)->merge_info)))
6037 return false;
6038 }
6039 else
6040 {
6041 if (! (o->flags & SEC_EXCLUDE) &&
6042 ! bfd_set_section_contents (output_bfd, o->output_section,
6043 contents, o->output_offset,
6044 (o->_cooked_size != 0
6045 ? o->_cooked_size
6046 : o->_raw_size)))
6047 return false;
6048 }
6049 }
6050
6051 return true;
6052 }
6053
6054 /* Generate a reloc when linking an ELF file. This is a reloc
6055 requested by the linker, and does come from any input file. This
6056 is used to build constructor and destructor tables when linking
6057 with -Ur. */
6058
6059 static boolean
6060 elf_reloc_link_order (output_bfd, info, output_section, link_order)
6061 bfd *output_bfd;
6062 struct bfd_link_info *info;
6063 asection *output_section;
6064 struct bfd_link_order *link_order;
6065 {
6066 reloc_howto_type *howto;
6067 long indx;
6068 bfd_vma offset;
6069 bfd_vma addend;
6070 struct elf_link_hash_entry **rel_hash_ptr;
6071 Elf_Internal_Shdr *rel_hdr;
6072 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
6073
6074 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
6075 if (howto == NULL)
6076 {
6077 bfd_set_error (bfd_error_bad_value);
6078 return false;
6079 }
6080
6081 addend = link_order->u.reloc.p->addend;
6082
6083 /* Figure out the symbol index. */
6084 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
6085 + elf_section_data (output_section)->rel_count
6086 + elf_section_data (output_section)->rel_count2);
6087 if (link_order->type == bfd_section_reloc_link_order)
6088 {
6089 indx = link_order->u.reloc.p->u.section->target_index;
6090 BFD_ASSERT (indx != 0);
6091 *rel_hash_ptr = NULL;
6092 }
6093 else
6094 {
6095 struct elf_link_hash_entry *h;
6096
6097 /* Treat a reloc against a defined symbol as though it were
6098 actually against the section. */
6099 h = ((struct elf_link_hash_entry *)
6100 bfd_wrapped_link_hash_lookup (output_bfd, info,
6101 link_order->u.reloc.p->u.name,
6102 false, false, true));
6103 if (h != NULL
6104 && (h->root.type == bfd_link_hash_defined
6105 || h->root.type == bfd_link_hash_defweak))
6106 {
6107 asection *section;
6108
6109 section = h->root.u.def.section;
6110 indx = section->output_section->target_index;
6111 *rel_hash_ptr = NULL;
6112 /* It seems that we ought to add the symbol value to the
6113 addend here, but in practice it has already been added
6114 because it was passed to constructor_callback. */
6115 addend += section->output_section->vma + section->output_offset;
6116 }
6117 else if (h != NULL)
6118 {
6119 /* Setting the index to -2 tells elf_link_output_extsym that
6120 this symbol is used by a reloc. */
6121 h->indx = -2;
6122 *rel_hash_ptr = h;
6123 indx = 0;
6124 }
6125 else
6126 {
6127 if (! ((*info->callbacks->unattached_reloc)
6128 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
6129 (asection *) NULL, (bfd_vma) 0)))
6130 return false;
6131 indx = 0;
6132 }
6133 }
6134
6135 /* If this is an inplace reloc, we must write the addend into the
6136 object file. */
6137 if (howto->partial_inplace && addend != 0)
6138 {
6139 bfd_size_type size;
6140 bfd_reloc_status_type rstat;
6141 bfd_byte *buf;
6142 boolean ok;
6143
6144 size = bfd_get_reloc_size (howto);
6145 buf = (bfd_byte *) bfd_zmalloc (size);
6146 if (buf == (bfd_byte *) NULL)
6147 return false;
6148 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
6149 switch (rstat)
6150 {
6151 case bfd_reloc_ok:
6152 break;
6153 default:
6154 case bfd_reloc_outofrange:
6155 abort ();
6156 case bfd_reloc_overflow:
6157 if (! ((*info->callbacks->reloc_overflow)
6158 (info,
6159 (link_order->type == bfd_section_reloc_link_order
6160 ? bfd_section_name (output_bfd,
6161 link_order->u.reloc.p->u.section)
6162 : link_order->u.reloc.p->u.name),
6163 howto->name, addend, (bfd *) NULL, (asection *) NULL,
6164 (bfd_vma) 0)))
6165 {
6166 free (buf);
6167 return false;
6168 }
6169 break;
6170 }
6171 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
6172 (file_ptr) link_order->offset, size);
6173 free (buf);
6174 if (! ok)
6175 return false;
6176 }
6177
6178 /* The address of a reloc is relative to the section in a
6179 relocateable file, and is a virtual address in an executable
6180 file. */
6181 offset = link_order->offset;
6182 if (! info->relocateable)
6183 offset += output_section->vma;
6184
6185 rel_hdr = &elf_section_data (output_section)->rel_hdr;
6186
6187 if (rel_hdr->sh_type == SHT_REL)
6188 {
6189 Elf_Internal_Rel *irel;
6190 Elf_External_Rel *erel;
6191 unsigned int i;
6192
6193 irel = (Elf_Internal_Rel *) bfd_zmalloc (bed->s->int_rels_per_ext_rel
6194 * sizeof (Elf_Internal_Rel));
6195 if (irel == NULL)
6196 return false;
6197
6198 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
6199 irel[i].r_offset = offset;
6200 irel[0].r_info = ELF_R_INFO (indx, howto->type);
6201
6202 erel = ((Elf_External_Rel *) rel_hdr->contents
6203 + elf_section_data (output_section)->rel_count);
6204
6205 if (bed->s->swap_reloc_out)
6206 (*bed->s->swap_reloc_out) (output_bfd, irel, (bfd_byte *) erel);
6207 else
6208 elf_swap_reloc_out (output_bfd, irel, erel);
6209
6210 free (irel);
6211 }
6212 else
6213 {
6214 Elf_Internal_Rela *irela;
6215 Elf_External_Rela *erela;
6216 unsigned int i;
6217
6218 irela = (Elf_Internal_Rela *) bfd_zmalloc (bed->s->int_rels_per_ext_rel
6219 * sizeof (Elf_Internal_Rela));
6220 if (irela == NULL)
6221 return false;
6222
6223 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
6224 irela[i].r_offset = offset;
6225 irela[0].r_info = ELF_R_INFO (indx, howto->type);
6226 irela[0].r_addend = addend;
6227
6228 erela = ((Elf_External_Rela *) rel_hdr->contents
6229 + elf_section_data (output_section)->rel_count);
6230
6231 if (bed->s->swap_reloca_out)
6232 (*bed->s->swap_reloca_out) (output_bfd, irela, (bfd_byte *) erela);
6233 else
6234 elf_swap_reloca_out (output_bfd, irela, erela);
6235 }
6236
6237 ++elf_section_data (output_section)->rel_count;
6238
6239 return true;
6240 }
6241 \f
6242 /* Allocate a pointer to live in a linker created section. */
6243
6244 boolean
6245 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6246 bfd *abfd;
6247 struct bfd_link_info *info;
6248 elf_linker_section_t *lsect;
6249 struct elf_link_hash_entry *h;
6250 const Elf_Internal_Rela *rel;
6251 {
6252 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6253 elf_linker_section_pointers_t *linker_section_ptr;
6254 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6255
6256 BFD_ASSERT (lsect != NULL);
6257
6258 /* Is this a global symbol? */
6259 if (h != NULL)
6260 {
6261 /* Has this symbol already been allocated, if so, our work is done */
6262 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6263 rel->r_addend,
6264 lsect->which))
6265 return true;
6266
6267 ptr_linker_section_ptr = &h->linker_section_pointer;
6268 /* Make sure this symbol is output as a dynamic symbol. */
6269 if (h->dynindx == -1)
6270 {
6271 if (! elf_link_record_dynamic_symbol (info, h))
6272 return false;
6273 }
6274
6275 if (lsect->rel_section)
6276 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6277 }
6278
6279 else /* Allocation of a pointer to a local symbol */
6280 {
6281 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6282
6283 /* Allocate a table to hold the local symbols if first time */
6284 if (!ptr)
6285 {
6286 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6287 register unsigned int i;
6288
6289 ptr = (elf_linker_section_pointers_t **)
6290 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6291
6292 if (!ptr)
6293 return false;
6294
6295 elf_local_ptr_offsets (abfd) = ptr;
6296 for (i = 0; i < num_symbols; i++)
6297 ptr[i] = (elf_linker_section_pointers_t *)0;
6298 }
6299
6300 /* Has this symbol already been allocated, if so, our work is done */
6301 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6302 rel->r_addend,
6303 lsect->which))
6304 return true;
6305
6306 ptr_linker_section_ptr = &ptr[r_symndx];
6307
6308 if (info->shared)
6309 {
6310 /* If we are generating a shared object, we need to
6311 output a R_<xxx>_RELATIVE reloc so that the
6312 dynamic linker can adjust this GOT entry. */
6313 BFD_ASSERT (lsect->rel_section != NULL);
6314 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6315 }
6316 }
6317
6318 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6319 from internal memory. */
6320 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6321 linker_section_ptr = (elf_linker_section_pointers_t *)
6322 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6323
6324 if (!linker_section_ptr)
6325 return false;
6326
6327 linker_section_ptr->next = *ptr_linker_section_ptr;
6328 linker_section_ptr->addend = rel->r_addend;
6329 linker_section_ptr->which = lsect->which;
6330 linker_section_ptr->written_address_p = false;
6331 *ptr_linker_section_ptr = linker_section_ptr;
6332
6333 #if 0
6334 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6335 {
6336 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6337 lsect->hole_offset += ARCH_SIZE / 8;
6338 lsect->sym_offset += ARCH_SIZE / 8;
6339 if (lsect->sym_hash) /* Bump up symbol value if needed */
6340 {
6341 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6342 #ifdef DEBUG
6343 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6344 lsect->sym_hash->root.root.string,
6345 (long)ARCH_SIZE / 8,
6346 (long)lsect->sym_hash->root.u.def.value);
6347 #endif
6348 }
6349 }
6350 else
6351 #endif
6352 linker_section_ptr->offset = lsect->section->_raw_size;
6353
6354 lsect->section->_raw_size += ARCH_SIZE / 8;
6355
6356 #ifdef DEBUG
6357 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6358 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6359 #endif
6360
6361 return true;
6362 }
6363 \f
6364 #if ARCH_SIZE==64
6365 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6366 #endif
6367 #if ARCH_SIZE==32
6368 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6369 #endif
6370
6371 /* Fill in the address for a pointer generated in a linker section. */
6372
6373 bfd_vma
6374 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6375 bfd *output_bfd;
6376 bfd *input_bfd;
6377 struct bfd_link_info *info;
6378 elf_linker_section_t *lsect;
6379 struct elf_link_hash_entry *h;
6380 bfd_vma relocation;
6381 const Elf_Internal_Rela *rel;
6382 int relative_reloc;
6383 {
6384 elf_linker_section_pointers_t *linker_section_ptr;
6385
6386 BFD_ASSERT (lsect != NULL);
6387
6388 if (h != NULL) /* global symbol */
6389 {
6390 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6391 rel->r_addend,
6392 lsect->which);
6393
6394 BFD_ASSERT (linker_section_ptr != NULL);
6395
6396 if (! elf_hash_table (info)->dynamic_sections_created
6397 || (info->shared
6398 && info->symbolic
6399 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6400 {
6401 /* This is actually a static link, or it is a
6402 -Bsymbolic link and the symbol is defined
6403 locally. We must initialize this entry in the
6404 global section.
6405
6406 When doing a dynamic link, we create a .rela.<xxx>
6407 relocation entry to initialize the value. This
6408 is done in the finish_dynamic_symbol routine. */
6409 if (!linker_section_ptr->written_address_p)
6410 {
6411 linker_section_ptr->written_address_p = true;
6412 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6413 lsect->section->contents + linker_section_ptr->offset);
6414 }
6415 }
6416 }
6417 else /* local symbol */
6418 {
6419 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6420 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6421 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6422 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6423 rel->r_addend,
6424 lsect->which);
6425
6426 BFD_ASSERT (linker_section_ptr != NULL);
6427
6428 /* Write out pointer if it hasn't been rewritten out before */
6429 if (!linker_section_ptr->written_address_p)
6430 {
6431 linker_section_ptr->written_address_p = true;
6432 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6433 lsect->section->contents + linker_section_ptr->offset);
6434
6435 if (info->shared)
6436 {
6437 asection *srel = lsect->rel_section;
6438 Elf_Internal_Rela *outrel;
6439 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
6440 unsigned int i;
6441
6442 outrel = (Elf_Internal_Rela *) bfd_zmalloc (sizeof (Elf_Internal_Rela)
6443 * bed->s->int_rels_per_ext_rel);
6444 if (outrel == NULL)
6445 {
6446 (*_bfd_error_handler) (_("Error: out of memory"));
6447 return 0;
6448 }
6449
6450 /* We need to generate a relative reloc for the dynamic linker. */
6451 if (!srel)
6452 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6453 lsect->rel_name);
6454
6455 BFD_ASSERT (srel != NULL);
6456
6457 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
6458 outrel[i].r_offset = (lsect->section->output_section->vma
6459 + lsect->section->output_offset
6460 + linker_section_ptr->offset);
6461 outrel[0].r_info = ELF_R_INFO (0, relative_reloc);
6462 outrel[0].r_addend = 0;
6463 elf_swap_reloca_out (output_bfd, outrel,
6464 (((Elf_External_Rela *)
6465 lsect->section->contents)
6466 + elf_section_data (lsect->section)->rel_count));
6467 ++elf_section_data (lsect->section)->rel_count;
6468
6469 free (outrel);
6470 }
6471 }
6472 }
6473
6474 relocation = (lsect->section->output_offset
6475 + linker_section_ptr->offset
6476 - lsect->hole_offset
6477 - lsect->sym_offset);
6478
6479 #ifdef DEBUG
6480 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6481 lsect->name, (long)relocation, (long)relocation);
6482 #endif
6483
6484 /* Subtract out the addend, because it will get added back in by the normal
6485 processing. */
6486 return relocation - linker_section_ptr->addend;
6487 }
6488 \f
6489 /* Garbage collect unused sections. */
6490
6491 static boolean elf_gc_mark
6492 PARAMS ((struct bfd_link_info *info, asection *sec,
6493 asection * (*gc_mark_hook)
6494 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6495 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6496
6497 static boolean elf_gc_sweep
6498 PARAMS ((struct bfd_link_info *info,
6499 boolean (*gc_sweep_hook)
6500 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6501 const Elf_Internal_Rela *relocs))));
6502
6503 static boolean elf_gc_sweep_symbol
6504 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6505
6506 static boolean elf_gc_allocate_got_offsets
6507 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6508
6509 static boolean elf_gc_propagate_vtable_entries_used
6510 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6511
6512 static boolean elf_gc_smash_unused_vtentry_relocs
6513 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6514
6515 /* The mark phase of garbage collection. For a given section, mark
6516 it, and all the sections which define symbols to which it refers. */
6517
6518 static boolean
6519 elf_gc_mark (info, sec, gc_mark_hook)
6520 struct bfd_link_info *info;
6521 asection *sec;
6522 asection * (*gc_mark_hook)
6523 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6524 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6525 {
6526 boolean ret = true;
6527
6528 sec->gc_mark = 1;
6529
6530 /* Look through the section relocs. */
6531
6532 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6533 {
6534 Elf_Internal_Rela *relstart, *rel, *relend;
6535 Elf_Internal_Shdr *symtab_hdr;
6536 struct elf_link_hash_entry **sym_hashes;
6537 size_t nlocsyms;
6538 size_t extsymoff;
6539 Elf_External_Sym *locsyms, *freesyms = NULL;
6540 bfd *input_bfd = sec->owner;
6541 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6542
6543 /* GCFIXME: how to arrange so that relocs and symbols are not
6544 reread continually? */
6545
6546 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6547 sym_hashes = elf_sym_hashes (input_bfd);
6548
6549 /* Read the local symbols. */
6550 if (elf_bad_symtab (input_bfd))
6551 {
6552 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6553 extsymoff = 0;
6554 }
6555 else
6556 extsymoff = nlocsyms = symtab_hdr->sh_info;
6557 if (symtab_hdr->contents)
6558 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6559 else if (nlocsyms == 0)
6560 locsyms = NULL;
6561 else
6562 {
6563 locsyms = freesyms =
6564 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6565 if (freesyms == NULL
6566 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6567 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6568 nlocsyms, input_bfd)
6569 != nlocsyms * sizeof (Elf_External_Sym)))
6570 {
6571 ret = false;
6572 goto out1;
6573 }
6574 }
6575
6576 /* Read the relocations. */
6577 relstart = (NAME(_bfd_elf,link_read_relocs)
6578 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6579 info->keep_memory));
6580 if (relstart == NULL)
6581 {
6582 ret = false;
6583 goto out1;
6584 }
6585 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6586
6587 for (rel = relstart; rel < relend; rel++)
6588 {
6589 unsigned long r_symndx;
6590 asection *rsec;
6591 struct elf_link_hash_entry *h;
6592 Elf_Internal_Sym s;
6593
6594 r_symndx = ELF_R_SYM (rel->r_info);
6595 if (r_symndx == 0)
6596 continue;
6597
6598 if (elf_bad_symtab (sec->owner))
6599 {
6600 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6601 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6602 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6603 else
6604 {
6605 h = sym_hashes[r_symndx - extsymoff];
6606 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6607 }
6608 }
6609 else if (r_symndx >= nlocsyms)
6610 {
6611 h = sym_hashes[r_symndx - extsymoff];
6612 rsec = (*gc_mark_hook) (sec->owner, info, rel, h, NULL);
6613 }
6614 else
6615 {
6616 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6617 rsec = (*gc_mark_hook) (sec->owner, info, rel, NULL, &s);
6618 }
6619
6620 if (rsec && !rsec->gc_mark)
6621 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6622 {
6623 ret = false;
6624 goto out2;
6625 }
6626 }
6627
6628 out2:
6629 if (!info->keep_memory)
6630 free (relstart);
6631 out1:
6632 if (freesyms)
6633 free (freesyms);
6634 }
6635
6636 return ret;
6637 }
6638
6639 /* The sweep phase of garbage collection. Remove all garbage sections. */
6640
6641 static boolean
6642 elf_gc_sweep (info, gc_sweep_hook)
6643 struct bfd_link_info *info;
6644 boolean (*gc_sweep_hook)
6645 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6646 const Elf_Internal_Rela *relocs));
6647 {
6648 bfd *sub;
6649
6650 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6651 {
6652 asection *o;
6653
6654 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6655 continue;
6656
6657 for (o = sub->sections; o != NULL; o = o->next)
6658 {
6659 /* Keep special sections. Keep .debug sections. */
6660 if ((o->flags & SEC_LINKER_CREATED)
6661 || (o->flags & SEC_DEBUGGING))
6662 o->gc_mark = 1;
6663
6664 if (o->gc_mark)
6665 continue;
6666
6667 /* Skip sweeping sections already excluded. */
6668 if (o->flags & SEC_EXCLUDE)
6669 continue;
6670
6671 /* Since this is early in the link process, it is simple
6672 to remove a section from the output. */
6673 o->flags |= SEC_EXCLUDE;
6674
6675 /* But we also have to update some of the relocation
6676 info we collected before. */
6677 if (gc_sweep_hook
6678 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6679 {
6680 Elf_Internal_Rela *internal_relocs;
6681 boolean r;
6682
6683 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6684 (o->owner, o, NULL, NULL, info->keep_memory));
6685 if (internal_relocs == NULL)
6686 return false;
6687
6688 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
6689
6690 if (!info->keep_memory)
6691 free (internal_relocs);
6692
6693 if (!r)
6694 return false;
6695 }
6696 }
6697 }
6698
6699 /* Remove the symbols that were in the swept sections from the dynamic
6700 symbol table. GCFIXME: Anyone know how to get them out of the
6701 static symbol table as well? */
6702 {
6703 int i = 0;
6704
6705 elf_link_hash_traverse (elf_hash_table (info),
6706 elf_gc_sweep_symbol,
6707 (PTR) &i);
6708
6709 elf_hash_table (info)->dynsymcount = i;
6710 }
6711
6712 return true;
6713 }
6714
6715 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6716
6717 static boolean
6718 elf_gc_sweep_symbol (h, idxptr)
6719 struct elf_link_hash_entry *h;
6720 PTR idxptr;
6721 {
6722 int *idx = (int *) idxptr;
6723
6724 if (h->dynindx != -1
6725 && ((h->root.type != bfd_link_hash_defined
6726 && h->root.type != bfd_link_hash_defweak)
6727 || h->root.u.def.section->gc_mark))
6728 h->dynindx = (*idx)++;
6729
6730 return true;
6731 }
6732
6733 /* Propogate collected vtable information. This is called through
6734 elf_link_hash_traverse. */
6735
6736 static boolean
6737 elf_gc_propagate_vtable_entries_used (h, okp)
6738 struct elf_link_hash_entry *h;
6739 PTR okp;
6740 {
6741 /* Those that are not vtables. */
6742 if (h->vtable_parent == NULL)
6743 return true;
6744
6745 /* Those vtables that do not have parents, we cannot merge. */
6746 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6747 return true;
6748
6749 /* If we've already been done, exit. */
6750 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6751 return true;
6752
6753 /* Make sure the parent's table is up to date. */
6754 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6755
6756 if (h->vtable_entries_used == NULL)
6757 {
6758 /* None of this table's entries were referenced. Re-use the
6759 parent's table. */
6760 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6761 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6762 }
6763 else
6764 {
6765 size_t n;
6766 boolean *cu, *pu;
6767
6768
6769 /* Or the parent's entries into ours. */
6770 cu = h->vtable_entries_used;
6771 cu[-1] = true;
6772 pu = h->vtable_parent->vtable_entries_used;
6773 if (pu != NULL)
6774 {
6775 asection *sec = h->root.u.def.section;
6776 struct elf_backend_data *bed = get_elf_backend_data (sec->owner);
6777 int file_align = bed->s->file_align;
6778
6779 n = h->vtable_parent->vtable_entries_size / file_align;
6780 while (--n != 0)
6781 {
6782 if (*pu) *cu = true;
6783 pu++, cu++;
6784 }
6785 }
6786 }
6787
6788 return true;
6789 }
6790
6791 static boolean
6792 elf_gc_smash_unused_vtentry_relocs (h, okp)
6793 struct elf_link_hash_entry *h;
6794 PTR okp;
6795 {
6796 asection *sec;
6797 bfd_vma hstart, hend;
6798 Elf_Internal_Rela *relstart, *relend, *rel;
6799 struct elf_backend_data *bed;
6800 int file_align;
6801
6802 /* Take care of both those symbols that do not describe vtables as
6803 well as those that are not loaded. */
6804 if (h->vtable_parent == NULL)
6805 return true;
6806
6807 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6808 || h->root.type == bfd_link_hash_defweak);
6809
6810 sec = h->root.u.def.section;
6811 hstart = h->root.u.def.value;
6812 hend = hstart + h->size;
6813
6814 relstart = (NAME(_bfd_elf,link_read_relocs)
6815 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6816 if (!relstart)
6817 return *(boolean *)okp = false;
6818 bed = get_elf_backend_data (sec->owner);
6819 file_align = bed->s->file_align;
6820
6821 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6822
6823 for (rel = relstart; rel < relend; ++rel)
6824 if (rel->r_offset >= hstart && rel->r_offset < hend)
6825 {
6826 /* If the entry is in use, do nothing. */
6827 if (h->vtable_entries_used
6828 && (rel->r_offset - hstart) < h->vtable_entries_size)
6829 {
6830 bfd_vma entry = (rel->r_offset - hstart) / file_align;
6831 if (h->vtable_entries_used[entry])
6832 continue;
6833 }
6834 /* Otherwise, kill it. */
6835 rel->r_offset = rel->r_info = rel->r_addend = 0;
6836 }
6837
6838 return true;
6839 }
6840
6841 /* Do mark and sweep of unused sections. */
6842
6843 boolean
6844 elf_gc_sections (abfd, info)
6845 bfd *abfd;
6846 struct bfd_link_info *info;
6847 {
6848 boolean ok = true;
6849 bfd *sub;
6850 asection * (*gc_mark_hook)
6851 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6852 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6853
6854 if (!get_elf_backend_data (abfd)->can_gc_sections
6855 || info->relocateable || info->emitrelocations
6856 || elf_hash_table (info)->dynamic_sections_created)
6857 return true;
6858
6859 /* Apply transitive closure to the vtable entry usage info. */
6860 elf_link_hash_traverse (elf_hash_table (info),
6861 elf_gc_propagate_vtable_entries_used,
6862 (PTR) &ok);
6863 if (!ok)
6864 return false;
6865
6866 /* Kill the vtable relocations that were not used. */
6867 elf_link_hash_traverse (elf_hash_table (info),
6868 elf_gc_smash_unused_vtentry_relocs,
6869 (PTR) &ok);
6870 if (!ok)
6871 return false;
6872
6873 /* Grovel through relocs to find out who stays ... */
6874
6875 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6876 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6877 {
6878 asection *o;
6879
6880 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6881 continue;
6882
6883 for (o = sub->sections; o != NULL; o = o->next)
6884 {
6885 if (o->flags & SEC_KEEP)
6886 if (!elf_gc_mark (info, o, gc_mark_hook))
6887 return false;
6888 }
6889 }
6890
6891 /* ... and mark SEC_EXCLUDE for those that go. */
6892 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6893 return false;
6894
6895 return true;
6896 }
6897 \f
6898 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6899
6900 boolean
6901 elf_gc_record_vtinherit (abfd, sec, h, offset)
6902 bfd *abfd;
6903 asection *sec;
6904 struct elf_link_hash_entry *h;
6905 bfd_vma offset;
6906 {
6907 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6908 struct elf_link_hash_entry **search, *child;
6909 bfd_size_type extsymcount;
6910
6911 /* The sh_info field of the symtab header tells us where the
6912 external symbols start. We don't care about the local symbols at
6913 this point. */
6914 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6915 if (!elf_bad_symtab (abfd))
6916 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6917
6918 sym_hashes = elf_sym_hashes (abfd);
6919 sym_hashes_end = sym_hashes + extsymcount;
6920
6921 /* Hunt down the child symbol, which is in this section at the same
6922 offset as the relocation. */
6923 for (search = sym_hashes; search != sym_hashes_end; ++search)
6924 {
6925 if ((child = *search) != NULL
6926 && (child->root.type == bfd_link_hash_defined
6927 || child->root.type == bfd_link_hash_defweak)
6928 && child->root.u.def.section == sec
6929 && child->root.u.def.value == offset)
6930 goto win;
6931 }
6932
6933 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6934 bfd_get_filename (abfd), sec->name,
6935 (unsigned long)offset);
6936 bfd_set_error (bfd_error_invalid_operation);
6937 return false;
6938
6939 win:
6940 if (!h)
6941 {
6942 /* This *should* only be the absolute section. It could potentially
6943 be that someone has defined a non-global vtable though, which
6944 would be bad. It isn't worth paging in the local symbols to be
6945 sure though; that case should simply be handled by the assembler. */
6946
6947 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6948 }
6949 else
6950 child->vtable_parent = h;
6951
6952 return true;
6953 }
6954
6955 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6956
6957 boolean
6958 elf_gc_record_vtentry (abfd, sec, h, addend)
6959 bfd *abfd ATTRIBUTE_UNUSED;
6960 asection *sec ATTRIBUTE_UNUSED;
6961 struct elf_link_hash_entry *h;
6962 bfd_vma addend;
6963 {
6964 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6965 int file_align = bed->s->file_align;
6966
6967 if (addend >= h->vtable_entries_size)
6968 {
6969 size_t size, bytes;
6970 boolean *ptr = h->vtable_entries_used;
6971
6972 /* While the symbol is undefined, we have to be prepared to handle
6973 a zero size. */
6974 if (h->root.type == bfd_link_hash_undefined)
6975 size = addend;
6976 else
6977 {
6978 size = h->size;
6979 if (size < addend)
6980 {
6981 /* Oops! We've got a reference past the defined end of
6982 the table. This is probably a bug -- shall we warn? */
6983 size = addend;
6984 }
6985 }
6986
6987 /* Allocate one extra entry for use as a "done" flag for the
6988 consolidation pass. */
6989 bytes = (size / file_align + 1) * sizeof (boolean);
6990
6991 if (ptr)
6992 {
6993 ptr = bfd_realloc (ptr - 1, bytes);
6994
6995 if (ptr != NULL)
6996 {
6997 size_t oldbytes;
6998
6999 oldbytes = (h->vtable_entries_size/file_align + 1) * sizeof (boolean);
7000 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
7001 }
7002 }
7003 else
7004 ptr = bfd_zmalloc (bytes);
7005
7006 if (ptr == NULL)
7007 return false;
7008
7009 /* And arrange for that done flag to be at index -1. */
7010 h->vtable_entries_used = ptr + 1;
7011 h->vtable_entries_size = size;
7012 }
7013
7014 h->vtable_entries_used[addend / file_align] = true;
7015
7016 return true;
7017 }
7018
7019 /* And an accompanying bit to work out final got entry offsets once
7020 we're done. Should be called from final_link. */
7021
7022 boolean
7023 elf_gc_common_finalize_got_offsets (abfd, info)
7024 bfd *abfd;
7025 struct bfd_link_info *info;
7026 {
7027 bfd *i;
7028 struct elf_backend_data *bed = get_elf_backend_data (abfd);
7029 bfd_vma gotoff;
7030
7031 /* The GOT offset is relative to the .got section, but the GOT header is
7032 put into the .got.plt section, if the backend uses it. */
7033 if (bed->want_got_plt)
7034 gotoff = 0;
7035 else
7036 gotoff = bed->got_header_size;
7037
7038 /* Do the local .got entries first. */
7039 for (i = info->input_bfds; i; i = i->link_next)
7040 {
7041 bfd_signed_vma *local_got;
7042 bfd_size_type j, locsymcount;
7043 Elf_Internal_Shdr *symtab_hdr;
7044
7045 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
7046 continue;
7047
7048 local_got = elf_local_got_refcounts (i);
7049 if (!local_got)
7050 continue;
7051
7052 symtab_hdr = &elf_tdata (i)->symtab_hdr;
7053 if (elf_bad_symtab (i))
7054 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
7055 else
7056 locsymcount = symtab_hdr->sh_info;
7057
7058 for (j = 0; j < locsymcount; ++j)
7059 {
7060 if (local_got[j] > 0)
7061 {
7062 local_got[j] = gotoff;
7063 gotoff += ARCH_SIZE / 8;
7064 }
7065 else
7066 local_got[j] = (bfd_vma) -1;
7067 }
7068 }
7069
7070 /* Then the global .got entries. .plt refcounts are handled by
7071 adjust_dynamic_symbol */
7072 elf_link_hash_traverse (elf_hash_table (info),
7073 elf_gc_allocate_got_offsets,
7074 (PTR) &gotoff);
7075 return true;
7076 }
7077
7078 /* We need a special top-level link routine to convert got reference counts
7079 to real got offsets. */
7080
7081 static boolean
7082 elf_gc_allocate_got_offsets (h, offarg)
7083 struct elf_link_hash_entry *h;
7084 PTR offarg;
7085 {
7086 bfd_vma *off = (bfd_vma *) offarg;
7087
7088 if (h->got.refcount > 0)
7089 {
7090 h->got.offset = off[0];
7091 off[0] += ARCH_SIZE / 8;
7092 }
7093 else
7094 h->got.offset = (bfd_vma) -1;
7095
7096 return true;
7097 }
7098
7099 /* Many folk need no more in the way of final link than this, once
7100 got entry reference counting is enabled. */
7101
7102 boolean
7103 elf_gc_common_final_link (abfd, info)
7104 bfd *abfd;
7105 struct bfd_link_info *info;
7106 {
7107 if (!elf_gc_common_finalize_got_offsets (abfd, info))
7108 return false;
7109
7110 /* Invoke the regular ELF backend linker to do all the work. */
7111 return elf_bfd_final_link (abfd, info);
7112 }
7113
7114 /* This function will be called though elf_link_hash_traverse to store
7115 all hash value of the exported symbols in an array. */
7116
7117 static boolean
7118 elf_collect_hash_codes (h, data)
7119 struct elf_link_hash_entry *h;
7120 PTR data;
7121 {
7122 unsigned long **valuep = (unsigned long **) data;
7123 const char *name;
7124 char *p;
7125 unsigned long ha;
7126 char *alc = NULL;
7127
7128 /* Ignore indirect symbols. These are added by the versioning code. */
7129 if (h->dynindx == -1)
7130 return true;
7131
7132 name = h->root.root.string;
7133 p = strchr (name, ELF_VER_CHR);
7134 if (p != NULL)
7135 {
7136 alc = bfd_malloc (p - name + 1);
7137 memcpy (alc, name, p - name);
7138 alc[p - name] = '\0';
7139 name = alc;
7140 }
7141
7142 /* Compute the hash value. */
7143 ha = bfd_elf_hash (name);
7144
7145 /* Store the found hash value in the array given as the argument. */
7146 *(*valuep)++ = ha;
7147
7148 /* And store it in the struct so that we can put it in the hash table
7149 later. */
7150 h->elf_hash_value = ha;
7151
7152 if (alc != NULL)
7153 free (alc);
7154
7155 return true;
7156 }
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