2000-09-12 Jason Eckhardt <jle@cygnus.com>
[deliverable/binutils-gdb.git] / bfd / elflink.h
1 /* ELF linker support.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20 /* ELF linker code. */
21
22 /* This struct is used to pass information to routines called via
23 elf_link_hash_traverse which must return failure. */
24
25 struct elf_info_failed
26 {
27 boolean failed;
28 struct bfd_link_info *info;
29 };
30
31 static boolean elf_link_add_object_symbols
32 PARAMS ((bfd *, struct bfd_link_info *));
33 static boolean elf_link_add_archive_symbols
34 PARAMS ((bfd *, struct bfd_link_info *));
35 static boolean elf_merge_symbol
36 PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
37 asection **, bfd_vma *, struct elf_link_hash_entry **,
38 boolean *, boolean *, boolean *, boolean));
39 static boolean elf_export_symbol
40 PARAMS ((struct elf_link_hash_entry *, PTR));
41 static boolean elf_fix_symbol_flags
42 PARAMS ((struct elf_link_hash_entry *, struct elf_info_failed *));
43 static boolean elf_adjust_dynamic_symbol
44 PARAMS ((struct elf_link_hash_entry *, PTR));
45 static boolean elf_link_find_version_dependencies
46 PARAMS ((struct elf_link_hash_entry *, PTR));
47 static boolean elf_link_find_version_dependencies
48 PARAMS ((struct elf_link_hash_entry *, PTR));
49 static boolean elf_link_assign_sym_version
50 PARAMS ((struct elf_link_hash_entry *, PTR));
51 static boolean elf_collect_hash_codes
52 PARAMS ((struct elf_link_hash_entry *, PTR));
53 static boolean elf_link_read_relocs_from_section
54 PARAMS ((bfd *, Elf_Internal_Shdr *, PTR, Elf_Internal_Rela *));
55 static void elf_link_output_relocs
56 PARAMS ((bfd *, asection *, Elf_Internal_Shdr *, Elf_Internal_Rela *));
57 static boolean elf_link_size_reloc_section
58 PARAMS ((bfd *, Elf_Internal_Shdr *, asection *));
59 static void elf_link_adjust_relocs
60 PARAMS ((bfd *, Elf_Internal_Shdr *, unsigned int,
61 struct elf_link_hash_entry **));
62
63 /* Given an ELF BFD, add symbols to the global hash table as
64 appropriate. */
65
66 boolean
67 elf_bfd_link_add_symbols (abfd, info)
68 bfd *abfd;
69 struct bfd_link_info *info;
70 {
71 switch (bfd_get_format (abfd))
72 {
73 case bfd_object:
74 return elf_link_add_object_symbols (abfd, info);
75 case bfd_archive:
76 return elf_link_add_archive_symbols (abfd, info);
77 default:
78 bfd_set_error (bfd_error_wrong_format);
79 return false;
80 }
81 }
82 \f
83 /* Return true iff this is a non-common definition of a symbol. */
84 static boolean
85 is_global_symbol_definition (abfd, sym)
86 bfd * abfd ATTRIBUTE_UNUSED;
87 Elf_Internal_Sym * sym;
88 {
89 /* Local symbols do not count, but target specific ones might. */
90 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
91 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
92 return false;
93
94 /* If the section is undefined, then so is the symbol. */
95 if (sym->st_shndx == SHN_UNDEF)
96 return false;
97
98 /* If the symbol is defined in the common section, then
99 it is a common definition and so does not count. */
100 if (sym->st_shndx == SHN_COMMON)
101 return false;
102
103 /* If the symbol is in a target specific section then we
104 must rely upon the backend to tell us what it is. */
105 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
106 /* FIXME - this function is not coded yet:
107
108 return _bfd_is_global_symbol_definition (abfd, sym);
109
110 Instead for now assume that the definition is not global,
111 Even if this is wrong, at least the linker will behave
112 in the same way that it used to do. */
113 return false;
114
115 return true;
116 }
117
118
119 /* Search the symbol table of the archive element of the archive ABFD
120 whoes archove map contains a mention of SYMDEF, and determine if
121 the symbol is defined in this element. */
122 static boolean
123 elf_link_is_defined_archive_symbol (abfd, symdef)
124 bfd * abfd;
125 carsym * symdef;
126 {
127 Elf_Internal_Shdr * hdr;
128 Elf_External_Sym * esym;
129 Elf_External_Sym * esymend;
130 Elf_External_Sym * buf = NULL;
131 size_t symcount;
132 size_t extsymcount;
133 size_t extsymoff;
134 boolean result = false;
135
136 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
137 if (abfd == (bfd *) NULL)
138 return false;
139
140 if (! bfd_check_format (abfd, bfd_object))
141 return false;
142
143 /* If we have already included the element containing this symbol in the
144 link then we do not need to include it again. Just claim that any symbol
145 it contains is not a definition, so that our caller will not decide to
146 (re)include this element. */
147 if (abfd->archive_pass)
148 return false;
149
150 /* Select the appropriate symbol table. */
151 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
152 hdr = &elf_tdata (abfd)->symtab_hdr;
153 else
154 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
155
156 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
157
158 /* The sh_info field of the symtab header tells us where the
159 external symbols start. We don't care about the local symbols. */
160 if (elf_bad_symtab (abfd))
161 {
162 extsymcount = symcount;
163 extsymoff = 0;
164 }
165 else
166 {
167 extsymcount = symcount - hdr->sh_info;
168 extsymoff = hdr->sh_info;
169 }
170
171 buf = ((Elf_External_Sym *)
172 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
173 if (buf == NULL && extsymcount != 0)
174 return false;
175
176 /* Read in the symbol table.
177 FIXME: This ought to be cached somewhere. */
178 if (bfd_seek (abfd,
179 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
180 SEEK_SET) != 0
181 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
182 != extsymcount * sizeof (Elf_External_Sym)))
183 {
184 free (buf);
185 return false;
186 }
187
188 /* Scan the symbol table looking for SYMDEF. */
189 esymend = buf + extsymcount;
190 for (esym = buf;
191 esym < esymend;
192 esym++)
193 {
194 Elf_Internal_Sym sym;
195 const char * name;
196
197 elf_swap_symbol_in (abfd, esym, & sym);
198
199 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
200 if (name == (const char *) NULL)
201 break;
202
203 if (strcmp (name, symdef->name) == 0)
204 {
205 result = is_global_symbol_definition (abfd, & sym);
206 break;
207 }
208 }
209
210 free (buf);
211
212 return result;
213 }
214 \f
215
216 /* Add symbols from an ELF archive file to the linker hash table. We
217 don't use _bfd_generic_link_add_archive_symbols because of a
218 problem which arises on UnixWare. The UnixWare libc.so is an
219 archive which includes an entry libc.so.1 which defines a bunch of
220 symbols. The libc.so archive also includes a number of other
221 object files, which also define symbols, some of which are the same
222 as those defined in libc.so.1. Correct linking requires that we
223 consider each object file in turn, and include it if it defines any
224 symbols we need. _bfd_generic_link_add_archive_symbols does not do
225 this; it looks through the list of undefined symbols, and includes
226 any object file which defines them. When this algorithm is used on
227 UnixWare, it winds up pulling in libc.so.1 early and defining a
228 bunch of symbols. This means that some of the other objects in the
229 archive are not included in the link, which is incorrect since they
230 precede libc.so.1 in the archive.
231
232 Fortunately, ELF archive handling is simpler than that done by
233 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
234 oddities. In ELF, if we find a symbol in the archive map, and the
235 symbol is currently undefined, we know that we must pull in that
236 object file.
237
238 Unfortunately, we do have to make multiple passes over the symbol
239 table until nothing further is resolved. */
240
241 static boolean
242 elf_link_add_archive_symbols (abfd, info)
243 bfd *abfd;
244 struct bfd_link_info *info;
245 {
246 symindex c;
247 boolean *defined = NULL;
248 boolean *included = NULL;
249 carsym *symdefs;
250 boolean loop;
251
252 if (! bfd_has_map (abfd))
253 {
254 /* An empty archive is a special case. */
255 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
256 return true;
257 bfd_set_error (bfd_error_no_armap);
258 return false;
259 }
260
261 /* Keep track of all symbols we know to be already defined, and all
262 files we know to be already included. This is to speed up the
263 second and subsequent passes. */
264 c = bfd_ardata (abfd)->symdef_count;
265 if (c == 0)
266 return true;
267 defined = (boolean *) bfd_malloc (c * sizeof (boolean));
268 included = (boolean *) bfd_malloc (c * sizeof (boolean));
269 if (defined == (boolean *) NULL || included == (boolean *) NULL)
270 goto error_return;
271 memset (defined, 0, c * sizeof (boolean));
272 memset (included, 0, c * sizeof (boolean));
273
274 symdefs = bfd_ardata (abfd)->symdefs;
275
276 do
277 {
278 file_ptr last;
279 symindex i;
280 carsym *symdef;
281 carsym *symdefend;
282
283 loop = false;
284 last = -1;
285
286 symdef = symdefs;
287 symdefend = symdef + c;
288 for (i = 0; symdef < symdefend; symdef++, i++)
289 {
290 struct elf_link_hash_entry *h;
291 bfd *element;
292 struct bfd_link_hash_entry *undefs_tail;
293 symindex mark;
294
295 if (defined[i] || included[i])
296 continue;
297 if (symdef->file_offset == last)
298 {
299 included[i] = true;
300 continue;
301 }
302
303 h = elf_link_hash_lookup (elf_hash_table (info), symdef->name,
304 false, false, false);
305
306 if (h == NULL)
307 {
308 char *p, *copy;
309
310 /* If this is a default version (the name contains @@),
311 look up the symbol again without the version. The
312 effect is that references to the symbol without the
313 version will be matched by the default symbol in the
314 archive. */
315
316 p = strchr (symdef->name, ELF_VER_CHR);
317 if (p == NULL || p[1] != ELF_VER_CHR)
318 continue;
319
320 copy = bfd_alloc (abfd, p - symdef->name + 1);
321 if (copy == NULL)
322 goto error_return;
323 memcpy (copy, symdef->name, p - symdef->name);
324 copy[p - symdef->name] = '\0';
325
326 h = elf_link_hash_lookup (elf_hash_table (info), copy,
327 false, false, false);
328
329 bfd_release (abfd, copy);
330 }
331
332 if (h == NULL)
333 continue;
334
335 if (h->root.type == bfd_link_hash_common)
336 {
337 /* We currently have a common symbol. The archive map contains
338 a reference to this symbol, so we may want to include it. We
339 only want to include it however, if this archive element
340 contains a definition of the symbol, not just another common
341 declaration of it.
342
343 Unfortunately some archivers (including GNU ar) will put
344 declarations of common symbols into their archive maps, as
345 well as real definitions, so we cannot just go by the archive
346 map alone. Instead we must read in the element's symbol
347 table and check that to see what kind of symbol definition
348 this is. */
349 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
350 continue;
351 }
352 else if (h->root.type != bfd_link_hash_undefined)
353 {
354 if (h->root.type != bfd_link_hash_undefweak)
355 defined[i] = true;
356 continue;
357 }
358
359 /* We need to include this archive member. */
360 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
361 if (element == (bfd *) NULL)
362 goto error_return;
363
364 if (! bfd_check_format (element, bfd_object))
365 goto error_return;
366
367 /* Doublecheck that we have not included this object
368 already--it should be impossible, but there may be
369 something wrong with the archive. */
370 if (element->archive_pass != 0)
371 {
372 bfd_set_error (bfd_error_bad_value);
373 goto error_return;
374 }
375 element->archive_pass = 1;
376
377 undefs_tail = info->hash->undefs_tail;
378
379 if (! (*info->callbacks->add_archive_element) (info, element,
380 symdef->name))
381 goto error_return;
382 if (! elf_link_add_object_symbols (element, info))
383 goto error_return;
384
385 /* If there are any new undefined symbols, we need to make
386 another pass through the archive in order to see whether
387 they can be defined. FIXME: This isn't perfect, because
388 common symbols wind up on undefs_tail and because an
389 undefined symbol which is defined later on in this pass
390 does not require another pass. This isn't a bug, but it
391 does make the code less efficient than it could be. */
392 if (undefs_tail != info->hash->undefs_tail)
393 loop = true;
394
395 /* Look backward to mark all symbols from this object file
396 which we have already seen in this pass. */
397 mark = i;
398 do
399 {
400 included[mark] = true;
401 if (mark == 0)
402 break;
403 --mark;
404 }
405 while (symdefs[mark].file_offset == symdef->file_offset);
406
407 /* We mark subsequent symbols from this object file as we go
408 on through the loop. */
409 last = symdef->file_offset;
410 }
411 }
412 while (loop);
413
414 free (defined);
415 free (included);
416
417 return true;
418
419 error_return:
420 if (defined != (boolean *) NULL)
421 free (defined);
422 if (included != (boolean *) NULL)
423 free (included);
424 return false;
425 }
426
427 /* This function is called when we want to define a new symbol. It
428 handles the various cases which arise when we find a definition in
429 a dynamic object, or when there is already a definition in a
430 dynamic object. The new symbol is described by NAME, SYM, PSEC,
431 and PVALUE. We set SYM_HASH to the hash table entry. We set
432 OVERRIDE if the old symbol is overriding a new definition. We set
433 TYPE_CHANGE_OK if it is OK for the type to change. We set
434 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
435 change, we mean that we shouldn't warn if the type or size does
436 change. DT_NEEDED indicates if it comes from a DT_NEEDED entry of
437 a shared object. */
438
439 static boolean
440 elf_merge_symbol (abfd, info, name, sym, psec, pvalue, sym_hash,
441 override, type_change_ok, size_change_ok, dt_needed)
442 bfd *abfd;
443 struct bfd_link_info *info;
444 const char *name;
445 Elf_Internal_Sym *sym;
446 asection **psec;
447 bfd_vma *pvalue;
448 struct elf_link_hash_entry **sym_hash;
449 boolean *override;
450 boolean *type_change_ok;
451 boolean *size_change_ok;
452 boolean dt_needed;
453 {
454 asection *sec;
455 struct elf_link_hash_entry *h;
456 int bind;
457 bfd *oldbfd;
458 boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
459
460 *override = false;
461
462 sec = *psec;
463 bind = ELF_ST_BIND (sym->st_info);
464
465 if (! bfd_is_und_section (sec))
466 h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
467 else
468 h = ((struct elf_link_hash_entry *)
469 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
470 if (h == NULL)
471 return false;
472 *sym_hash = h;
473
474 /* This code is for coping with dynamic objects, and is only useful
475 if we are doing an ELF link. */
476 if (info->hash->creator != abfd->xvec)
477 return true;
478
479 /* For merging, we only care about real symbols. */
480
481 while (h->root.type == bfd_link_hash_indirect
482 || h->root.type == bfd_link_hash_warning)
483 h = (struct elf_link_hash_entry *) h->root.u.i.link;
484
485 /* If we just created the symbol, mark it as being an ELF symbol.
486 Other than that, there is nothing to do--there is no merge issue
487 with a newly defined symbol--so we just return. */
488
489 if (h->root.type == bfd_link_hash_new)
490 {
491 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
492 return true;
493 }
494
495 /* OLDBFD is a BFD associated with the existing symbol. */
496
497 switch (h->root.type)
498 {
499 default:
500 oldbfd = NULL;
501 break;
502
503 case bfd_link_hash_undefined:
504 case bfd_link_hash_undefweak:
505 oldbfd = h->root.u.undef.abfd;
506 break;
507
508 case bfd_link_hash_defined:
509 case bfd_link_hash_defweak:
510 oldbfd = h->root.u.def.section->owner;
511 break;
512
513 case bfd_link_hash_common:
514 oldbfd = h->root.u.c.p->section->owner;
515 break;
516 }
517
518 /* In cases involving weak versioned symbols, we may wind up trying
519 to merge a symbol with itself. Catch that here, to avoid the
520 confusion that results if we try to override a symbol with
521 itself. The additional tests catch cases like
522 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
523 dynamic object, which we do want to handle here. */
524 if (abfd == oldbfd
525 && ((abfd->flags & DYNAMIC) == 0
526 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0))
527 return true;
528
529 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
530 respectively, is from a dynamic object. */
531
532 if ((abfd->flags & DYNAMIC) != 0)
533 newdyn = true;
534 else
535 newdyn = false;
536
537 if (oldbfd != NULL)
538 olddyn = (oldbfd->flags & DYNAMIC) != 0;
539 else
540 {
541 asection *hsec;
542
543 /* This code handles the special SHN_MIPS_{TEXT,DATA} section
544 indices used by MIPS ELF. */
545 switch (h->root.type)
546 {
547 default:
548 hsec = NULL;
549 break;
550
551 case bfd_link_hash_defined:
552 case bfd_link_hash_defweak:
553 hsec = h->root.u.def.section;
554 break;
555
556 case bfd_link_hash_common:
557 hsec = h->root.u.c.p->section;
558 break;
559 }
560
561 if (hsec == NULL)
562 olddyn = false;
563 else
564 olddyn = (hsec->symbol->flags & BSF_DYNAMIC) != 0;
565 }
566
567 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
568 respectively, appear to be a definition rather than reference. */
569
570 if (bfd_is_und_section (sec) || bfd_is_com_section (sec))
571 newdef = false;
572 else
573 newdef = true;
574
575 if (h->root.type == bfd_link_hash_undefined
576 || h->root.type == bfd_link_hash_undefweak
577 || h->root.type == bfd_link_hash_common)
578 olddef = false;
579 else
580 olddef = true;
581
582 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
583 symbol, respectively, appears to be a common symbol in a dynamic
584 object. If a symbol appears in an uninitialized section, and is
585 not weak, and is not a function, then it may be a common symbol
586 which was resolved when the dynamic object was created. We want
587 to treat such symbols specially, because they raise special
588 considerations when setting the symbol size: if the symbol
589 appears as a common symbol in a regular object, and the size in
590 the regular object is larger, we must make sure that we use the
591 larger size. This problematic case can always be avoided in C,
592 but it must be handled correctly when using Fortran shared
593 libraries.
594
595 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
596 likewise for OLDDYNCOMMON and OLDDEF.
597
598 Note that this test is just a heuristic, and that it is quite
599 possible to have an uninitialized symbol in a shared object which
600 is really a definition, rather than a common symbol. This could
601 lead to some minor confusion when the symbol really is a common
602 symbol in some regular object. However, I think it will be
603 harmless. */
604
605 if (newdyn
606 && newdef
607 && (sec->flags & SEC_ALLOC) != 0
608 && (sec->flags & SEC_LOAD) == 0
609 && sym->st_size > 0
610 && bind != STB_WEAK
611 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
612 newdyncommon = true;
613 else
614 newdyncommon = false;
615
616 if (olddyn
617 && olddef
618 && h->root.type == bfd_link_hash_defined
619 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
620 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
621 && (h->root.u.def.section->flags & SEC_LOAD) == 0
622 && h->size > 0
623 && h->type != STT_FUNC)
624 olddyncommon = true;
625 else
626 olddyncommon = false;
627
628 /* It's OK to change the type if either the existing symbol or the
629 new symbol is weak unless it comes from a DT_NEEDED entry of
630 a shared object, in which case, the DT_NEEDED entry may not be
631 required at the run time. */
632
633 if ((! dt_needed && h->root.type == bfd_link_hash_defweak)
634 || h->root.type == bfd_link_hash_undefweak
635 || bind == STB_WEAK)
636 *type_change_ok = true;
637
638 /* It's OK to change the size if either the existing symbol or the
639 new symbol is weak, or if the old symbol is undefined. */
640
641 if (*type_change_ok
642 || h->root.type == bfd_link_hash_undefined)
643 *size_change_ok = true;
644
645 /* If both the old and the new symbols look like common symbols in a
646 dynamic object, set the size of the symbol to the larger of the
647 two. */
648
649 if (olddyncommon
650 && newdyncommon
651 && sym->st_size != h->size)
652 {
653 /* Since we think we have two common symbols, issue a multiple
654 common warning if desired. Note that we only warn if the
655 size is different. If the size is the same, we simply let
656 the old symbol override the new one as normally happens with
657 symbols defined in dynamic objects. */
658
659 if (! ((*info->callbacks->multiple_common)
660 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
661 h->size, abfd, bfd_link_hash_common, sym->st_size)))
662 return false;
663
664 if (sym->st_size > h->size)
665 h->size = sym->st_size;
666
667 *size_change_ok = true;
668 }
669
670 /* If we are looking at a dynamic object, and we have found a
671 definition, we need to see if the symbol was already defined by
672 some other object. If so, we want to use the existing
673 definition, and we do not want to report a multiple symbol
674 definition error; we do this by clobbering *PSEC to be
675 bfd_und_section_ptr.
676
677 We treat a common symbol as a definition if the symbol in the
678 shared library is a function, since common symbols always
679 represent variables; this can cause confusion in principle, but
680 any such confusion would seem to indicate an erroneous program or
681 shared library. We also permit a common symbol in a regular
682 object to override a weak symbol in a shared object.
683
684 We prefer a non-weak definition in a shared library to a weak
685 definition in the executable unless it comes from a DT_NEEDED
686 entry of a shared object, in which case, the DT_NEEDED entry
687 may not be required at the run time. */
688
689 if (newdyn
690 && newdef
691 && (olddef
692 || (h->root.type == bfd_link_hash_common
693 && (bind == STB_WEAK
694 || ELF_ST_TYPE (sym->st_info) == STT_FUNC)))
695 && (h->root.type != bfd_link_hash_defweak
696 || dt_needed
697 || bind == STB_WEAK))
698 {
699 *override = true;
700 newdef = false;
701 newdyncommon = false;
702
703 *psec = sec = bfd_und_section_ptr;
704 *size_change_ok = true;
705
706 /* If we get here when the old symbol is a common symbol, then
707 we are explicitly letting it override a weak symbol or
708 function in a dynamic object, and we don't want to warn about
709 a type change. If the old symbol is a defined symbol, a type
710 change warning may still be appropriate. */
711
712 if (h->root.type == bfd_link_hash_common)
713 *type_change_ok = true;
714 }
715
716 /* Handle the special case of an old common symbol merging with a
717 new symbol which looks like a common symbol in a shared object.
718 We change *PSEC and *PVALUE to make the new symbol look like a
719 common symbol, and let _bfd_generic_link_add_one_symbol will do
720 the right thing. */
721
722 if (newdyncommon
723 && h->root.type == bfd_link_hash_common)
724 {
725 *override = true;
726 newdef = false;
727 newdyncommon = false;
728 *pvalue = sym->st_size;
729 *psec = sec = bfd_com_section_ptr;
730 *size_change_ok = true;
731 }
732
733 /* If the old symbol is from a dynamic object, and the new symbol is
734 a definition which is not from a dynamic object, then the new
735 symbol overrides the old symbol. Symbols from regular files
736 always take precedence over symbols from dynamic objects, even if
737 they are defined after the dynamic object in the link.
738
739 As above, we again permit a common symbol in a regular object to
740 override a definition in a shared object if the shared object
741 symbol is a function or is weak.
742
743 As above, we permit a non-weak definition in a shared object to
744 override a weak definition in a regular object. */
745
746 if (! newdyn
747 && (newdef
748 || (bfd_is_com_section (sec)
749 && (h->root.type == bfd_link_hash_defweak
750 || h->type == STT_FUNC)))
751 && olddyn
752 && olddef
753 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
754 && (bind != STB_WEAK
755 || h->root.type == bfd_link_hash_defweak))
756 {
757 /* Change the hash table entry to undefined, and let
758 _bfd_generic_link_add_one_symbol do the right thing with the
759 new definition. */
760
761 h->root.type = bfd_link_hash_undefined;
762 h->root.u.undef.abfd = h->root.u.def.section->owner;
763 *size_change_ok = true;
764
765 olddef = false;
766 olddyncommon = false;
767
768 /* We again permit a type change when a common symbol may be
769 overriding a function. */
770
771 if (bfd_is_com_section (sec))
772 *type_change_ok = true;
773
774 /* This union may have been set to be non-NULL when this symbol
775 was seen in a dynamic object. We must force the union to be
776 NULL, so that it is correct for a regular symbol. */
777
778 h->verinfo.vertree = NULL;
779
780 /* In this special case, if H is the target of an indirection,
781 we want the caller to frob with H rather than with the
782 indirect symbol. That will permit the caller to redefine the
783 target of the indirection, rather than the indirect symbol
784 itself. FIXME: This will break the -y option if we store a
785 symbol with a different name. */
786 *sym_hash = h;
787 }
788
789 /* Handle the special case of a new common symbol merging with an
790 old symbol that looks like it might be a common symbol defined in
791 a shared object. Note that we have already handled the case in
792 which a new common symbol should simply override the definition
793 in the shared library. */
794
795 if (! newdyn
796 && bfd_is_com_section (sec)
797 && olddyncommon)
798 {
799 /* It would be best if we could set the hash table entry to a
800 common symbol, but we don't know what to use for the section
801 or the alignment. */
802 if (! ((*info->callbacks->multiple_common)
803 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
804 h->size, abfd, bfd_link_hash_common, sym->st_size)))
805 return false;
806
807 /* If the predumed common symbol in the dynamic object is
808 larger, pretend that the new symbol has its size. */
809
810 if (h->size > *pvalue)
811 *pvalue = h->size;
812
813 /* FIXME: We no longer know the alignment required by the symbol
814 in the dynamic object, so we just wind up using the one from
815 the regular object. */
816
817 olddef = false;
818 olddyncommon = false;
819
820 h->root.type = bfd_link_hash_undefined;
821 h->root.u.undef.abfd = h->root.u.def.section->owner;
822
823 *size_change_ok = true;
824 *type_change_ok = true;
825
826 h->verinfo.vertree = NULL;
827 }
828
829 /* Handle the special case of a weak definition in a regular object
830 followed by a non-weak definition in a shared object. In this
831 case, we prefer the definition in the shared object unless it
832 comes from a DT_NEEDED entry of a shared object, in which case,
833 the DT_NEEDED entry may not be required at the run time. */
834 if (olddef
835 && ! dt_needed
836 && h->root.type == bfd_link_hash_defweak
837 && newdef
838 && newdyn
839 && bind != STB_WEAK)
840 {
841 /* To make this work we have to frob the flags so that the rest
842 of the code does not think we are using the regular
843 definition. */
844 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
845 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
846 else if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0)
847 h->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
848 h->elf_link_hash_flags &= ~ (ELF_LINK_HASH_DEF_REGULAR
849 | ELF_LINK_HASH_DEF_DYNAMIC);
850
851 /* If H is the target of an indirection, we want the caller to
852 use H rather than the indirect symbol. Otherwise if we are
853 defining a new indirect symbol we will wind up attaching it
854 to the entry we are overriding. */
855 *sym_hash = h;
856 }
857
858 /* Handle the special case of a non-weak definition in a shared
859 object followed by a weak definition in a regular object. In
860 this case we prefer to definition in the shared object. To make
861 this work we have to tell the caller to not treat the new symbol
862 as a definition. */
863 if (olddef
864 && olddyn
865 && h->root.type != bfd_link_hash_defweak
866 && newdef
867 && ! newdyn
868 && bind == STB_WEAK)
869 *override = true;
870
871 return true;
872 }
873
874 /* Add symbols from an ELF object file to the linker hash table. */
875
876 static boolean
877 elf_link_add_object_symbols (abfd, info)
878 bfd *abfd;
879 struct bfd_link_info *info;
880 {
881 boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *,
882 const Elf_Internal_Sym *,
883 const char **, flagword *,
884 asection **, bfd_vma *));
885 boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *,
886 asection *, const Elf_Internal_Rela *));
887 boolean collect;
888 Elf_Internal_Shdr *hdr;
889 size_t symcount;
890 size_t extsymcount;
891 size_t extsymoff;
892 Elf_External_Sym *buf = NULL;
893 struct elf_link_hash_entry **sym_hash;
894 boolean dynamic;
895 bfd_byte *dynver = NULL;
896 Elf_External_Versym *extversym = NULL;
897 Elf_External_Versym *ever;
898 Elf_External_Dyn *dynbuf = NULL;
899 struct elf_link_hash_entry *weaks;
900 Elf_External_Sym *esym;
901 Elf_External_Sym *esymend;
902 struct elf_backend_data *bed;
903 boolean dt_needed;
904
905 bed = get_elf_backend_data (abfd);
906 add_symbol_hook = bed->elf_add_symbol_hook;
907 collect = bed->collect;
908
909 if ((abfd->flags & DYNAMIC) == 0)
910 dynamic = false;
911 else
912 {
913 dynamic = true;
914
915 /* You can't use -r against a dynamic object. Also, there's no
916 hope of using a dynamic object which does not exactly match
917 the format of the output file. */
918 if (info->relocateable || info->hash->creator != abfd->xvec)
919 {
920 bfd_set_error (bfd_error_invalid_operation);
921 goto error_return;
922 }
923 }
924
925 /* As a GNU extension, any input sections which are named
926 .gnu.warning.SYMBOL are treated as warning symbols for the given
927 symbol. This differs from .gnu.warning sections, which generate
928 warnings when they are included in an output file. */
929 if (! info->shared)
930 {
931 asection *s;
932
933 for (s = abfd->sections; s != NULL; s = s->next)
934 {
935 const char *name;
936
937 name = bfd_get_section_name (abfd, s);
938 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
939 {
940 char *msg;
941 bfd_size_type sz;
942
943 name += sizeof ".gnu.warning." - 1;
944
945 /* If this is a shared object, then look up the symbol
946 in the hash table. If it is there, and it is already
947 been defined, then we will not be using the entry
948 from this shared object, so we don't need to warn.
949 FIXME: If we see the definition in a regular object
950 later on, we will warn, but we shouldn't. The only
951 fix is to keep track of what warnings we are supposed
952 to emit, and then handle them all at the end of the
953 link. */
954 if (dynamic && abfd->xvec == info->hash->creator)
955 {
956 struct elf_link_hash_entry *h;
957
958 h = elf_link_hash_lookup (elf_hash_table (info), name,
959 false, false, true);
960
961 /* FIXME: What about bfd_link_hash_common? */
962 if (h != NULL
963 && (h->root.type == bfd_link_hash_defined
964 || h->root.type == bfd_link_hash_defweak))
965 {
966 /* We don't want to issue this warning. Clobber
967 the section size so that the warning does not
968 get copied into the output file. */
969 s->_raw_size = 0;
970 continue;
971 }
972 }
973
974 sz = bfd_section_size (abfd, s);
975 msg = (char *) bfd_alloc (abfd, sz + 1);
976 if (msg == NULL)
977 goto error_return;
978
979 if (! bfd_get_section_contents (abfd, s, msg, (file_ptr) 0, sz))
980 goto error_return;
981
982 msg[sz] = '\0';
983
984 if (! (_bfd_generic_link_add_one_symbol
985 (info, abfd, name, BSF_WARNING, s, (bfd_vma) 0, msg,
986 false, collect, (struct bfd_link_hash_entry **) NULL)))
987 goto error_return;
988
989 if (! info->relocateable)
990 {
991 /* Clobber the section size so that the warning does
992 not get copied into the output file. */
993 s->_raw_size = 0;
994 }
995 }
996 }
997 }
998
999 /* If this is a dynamic object, we always link against the .dynsym
1000 symbol table, not the .symtab symbol table. The dynamic linker
1001 will only see the .dynsym symbol table, so there is no reason to
1002 look at .symtab for a dynamic object. */
1003
1004 if (! dynamic || elf_dynsymtab (abfd) == 0)
1005 hdr = &elf_tdata (abfd)->symtab_hdr;
1006 else
1007 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1008
1009 if (dynamic)
1010 {
1011 /* Read in any version definitions. */
1012
1013 if (! _bfd_elf_slurp_version_tables (abfd))
1014 goto error_return;
1015
1016 /* Read in the symbol versions, but don't bother to convert them
1017 to internal format. */
1018 if (elf_dynversym (abfd) != 0)
1019 {
1020 Elf_Internal_Shdr *versymhdr;
1021
1022 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
1023 extversym = (Elf_External_Versym *) bfd_malloc (hdr->sh_size);
1024 if (extversym == NULL)
1025 goto error_return;
1026 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
1027 || (bfd_read ((PTR) extversym, 1, versymhdr->sh_size, abfd)
1028 != versymhdr->sh_size))
1029 goto error_return;
1030 }
1031 }
1032
1033 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1034
1035 /* The sh_info field of the symtab header tells us where the
1036 external symbols start. We don't care about the local symbols at
1037 this point. */
1038 if (elf_bad_symtab (abfd))
1039 {
1040 extsymcount = symcount;
1041 extsymoff = 0;
1042 }
1043 else
1044 {
1045 extsymcount = symcount - hdr->sh_info;
1046 extsymoff = hdr->sh_info;
1047 }
1048
1049 buf = ((Elf_External_Sym *)
1050 bfd_malloc (extsymcount * sizeof (Elf_External_Sym)));
1051 if (buf == NULL && extsymcount != 0)
1052 goto error_return;
1053
1054 /* We store a pointer to the hash table entry for each external
1055 symbol. */
1056 sym_hash = ((struct elf_link_hash_entry **)
1057 bfd_alloc (abfd,
1058 extsymcount * sizeof (struct elf_link_hash_entry *)));
1059 if (sym_hash == NULL)
1060 goto error_return;
1061 elf_sym_hashes (abfd) = sym_hash;
1062
1063 dt_needed = false;
1064
1065 if (! dynamic)
1066 {
1067 /* If we are creating a shared library, create all the dynamic
1068 sections immediately. We need to attach them to something,
1069 so we attach them to this BFD, provided it is the right
1070 format. FIXME: If there are no input BFD's of the same
1071 format as the output, we can't make a shared library. */
1072 if (info->shared
1073 && ! elf_hash_table (info)->dynamic_sections_created
1074 && abfd->xvec == info->hash->creator)
1075 {
1076 if (! elf_link_create_dynamic_sections (abfd, info))
1077 goto error_return;
1078 }
1079 }
1080 else
1081 {
1082 asection *s;
1083 boolean add_needed;
1084 const char *name;
1085 bfd_size_type oldsize;
1086 bfd_size_type strindex;
1087
1088 /* Find the name to use in a DT_NEEDED entry that refers to this
1089 object. If the object has a DT_SONAME entry, we use it.
1090 Otherwise, if the generic linker stuck something in
1091 elf_dt_name, we use that. Otherwise, we just use the file
1092 name. If the generic linker put a null string into
1093 elf_dt_name, we don't make a DT_NEEDED entry at all, even if
1094 there is a DT_SONAME entry. */
1095 add_needed = true;
1096 name = bfd_get_filename (abfd);
1097 if (elf_dt_name (abfd) != NULL)
1098 {
1099 name = elf_dt_name (abfd);
1100 if (*name == '\0')
1101 {
1102 if (elf_dt_soname (abfd) != NULL)
1103 dt_needed = true;
1104
1105 add_needed = false;
1106 }
1107 }
1108 s = bfd_get_section_by_name (abfd, ".dynamic");
1109 if (s != NULL)
1110 {
1111 Elf_External_Dyn *extdyn;
1112 Elf_External_Dyn *extdynend;
1113 int elfsec;
1114 unsigned long link;
1115 int rpath;
1116 int runpath;
1117
1118 dynbuf = (Elf_External_Dyn *) bfd_malloc ((size_t) s->_raw_size);
1119 if (dynbuf == NULL)
1120 goto error_return;
1121
1122 if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf,
1123 (file_ptr) 0, s->_raw_size))
1124 goto error_return;
1125
1126 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1127 if (elfsec == -1)
1128 goto error_return;
1129 link = elf_elfsections (abfd)[elfsec]->sh_link;
1130
1131 {
1132 /* The shared libraries distributed with hpux11 have a bogus
1133 sh_link field for the ".dynamic" section. This code detects
1134 when LINK refers to a section that is not a string table and
1135 tries to find the string table for the ".dynsym" section
1136 instead. */
1137 Elf_Internal_Shdr *hdr = elf_elfsections (abfd)[link];
1138 if (hdr->sh_type != SHT_STRTAB)
1139 {
1140 asection *s = bfd_get_section_by_name (abfd, ".dynsym");
1141 int elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
1142 if (elfsec == -1)
1143 goto error_return;
1144 link = elf_elfsections (abfd)[elfsec]->sh_link;
1145 }
1146 }
1147
1148 extdyn = dynbuf;
1149 extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn);
1150 rpath = 0;
1151 runpath = 0;
1152 for (; extdyn < extdynend; extdyn++)
1153 {
1154 Elf_Internal_Dyn dyn;
1155
1156 elf_swap_dyn_in (abfd, extdyn, &dyn);
1157 if (dyn.d_tag == DT_SONAME)
1158 {
1159 name = bfd_elf_string_from_elf_section (abfd, link,
1160 dyn.d_un.d_val);
1161 if (name == NULL)
1162 goto error_return;
1163 }
1164 if (dyn.d_tag == DT_NEEDED)
1165 {
1166 struct bfd_link_needed_list *n, **pn;
1167 char *fnm, *anm;
1168
1169 n = ((struct bfd_link_needed_list *)
1170 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1171 fnm = bfd_elf_string_from_elf_section (abfd, link,
1172 dyn.d_un.d_val);
1173 if (n == NULL || fnm == NULL)
1174 goto error_return;
1175 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1176 if (anm == NULL)
1177 goto error_return;
1178 strcpy (anm, fnm);
1179 n->name = anm;
1180 n->by = abfd;
1181 n->next = NULL;
1182 for (pn = &elf_hash_table (info)->needed;
1183 *pn != NULL;
1184 pn = &(*pn)->next)
1185 ;
1186 *pn = n;
1187 }
1188 if (dyn.d_tag == DT_RUNPATH)
1189 {
1190 struct bfd_link_needed_list *n, **pn;
1191 char *fnm, *anm;
1192
1193 /* When we see DT_RPATH before DT_RUNPATH, we have
1194 to free runpath. */
1195 if (rpath && elf_hash_table (info)->runpath)
1196 {
1197 struct bfd_link_needed_list *nn;
1198 for (n = elf_hash_table (info)->runpath;
1199 n != NULL; n = nn)
1200 {
1201 nn = n->next;
1202 bfd_release (abfd, n);
1203 }
1204 bfd_release (abfd, elf_hash_table (info)->runpath);
1205 elf_hash_table (info)->runpath = NULL;
1206 }
1207
1208 n = ((struct bfd_link_needed_list *)
1209 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1210 fnm = bfd_elf_string_from_elf_section (abfd, link,
1211 dyn.d_un.d_val);
1212 if (n == NULL || fnm == NULL)
1213 goto error_return;
1214 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1215 if (anm == NULL)
1216 goto error_return;
1217 strcpy (anm, fnm);
1218 n->name = anm;
1219 n->by = abfd;
1220 n->next = NULL;
1221 for (pn = &elf_hash_table (info)->runpath;
1222 *pn != NULL;
1223 pn = &(*pn)->next)
1224 ;
1225 *pn = n;
1226 runpath = 1;
1227 rpath = 0;
1228 }
1229 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
1230 if (!runpath && dyn.d_tag == DT_RPATH)
1231 {
1232 struct bfd_link_needed_list *n, **pn;
1233 char *fnm, *anm;
1234
1235 n = ((struct bfd_link_needed_list *)
1236 bfd_alloc (abfd, sizeof (struct bfd_link_needed_list)));
1237 fnm = bfd_elf_string_from_elf_section (abfd, link,
1238 dyn.d_un.d_val);
1239 if (n == NULL || fnm == NULL)
1240 goto error_return;
1241 anm = bfd_alloc (abfd, strlen (fnm) + 1);
1242 if (anm == NULL)
1243 goto error_return;
1244 strcpy (anm, fnm);
1245 n->name = anm;
1246 n->by = abfd;
1247 n->next = NULL;
1248 for (pn = &elf_hash_table (info)->runpath;
1249 *pn != NULL;
1250 pn = &(*pn)->next)
1251 ;
1252 *pn = n;
1253 rpath = 1;
1254 }
1255 }
1256
1257 free (dynbuf);
1258 dynbuf = NULL;
1259 }
1260
1261 /* We do not want to include any of the sections in a dynamic
1262 object in the output file. We hack by simply clobbering the
1263 list of sections in the BFD. This could be handled more
1264 cleanly by, say, a new section flag; the existing
1265 SEC_NEVER_LOAD flag is not the one we want, because that one
1266 still implies that the section takes up space in the output
1267 file. */
1268 abfd->sections = NULL;
1269 abfd->section_count = 0;
1270
1271 /* If this is the first dynamic object found in the link, create
1272 the special sections required for dynamic linking. */
1273 if (! elf_hash_table (info)->dynamic_sections_created)
1274 {
1275 if (! elf_link_create_dynamic_sections (abfd, info))
1276 goto error_return;
1277 }
1278
1279 if (add_needed)
1280 {
1281 /* Add a DT_NEEDED entry for this dynamic object. */
1282 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1283 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name,
1284 true, false);
1285 if (strindex == (bfd_size_type) -1)
1286 goto error_return;
1287
1288 if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1289 {
1290 asection *sdyn;
1291 Elf_External_Dyn *dyncon, *dynconend;
1292
1293 /* The hash table size did not change, which means that
1294 the dynamic object name was already entered. If we
1295 have already included this dynamic object in the
1296 link, just ignore it. There is no reason to include
1297 a particular dynamic object more than once. */
1298 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1299 ".dynamic");
1300 BFD_ASSERT (sdyn != NULL);
1301
1302 dyncon = (Elf_External_Dyn *) sdyn->contents;
1303 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1304 sdyn->_raw_size);
1305 for (; dyncon < dynconend; dyncon++)
1306 {
1307 Elf_Internal_Dyn dyn;
1308
1309 elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon,
1310 &dyn);
1311 if (dyn.d_tag == DT_NEEDED
1312 && dyn.d_un.d_val == strindex)
1313 {
1314 if (buf != NULL)
1315 free (buf);
1316 if (extversym != NULL)
1317 free (extversym);
1318 return true;
1319 }
1320 }
1321 }
1322
1323 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
1324 goto error_return;
1325 }
1326
1327 /* Save the SONAME, if there is one, because sometimes the
1328 linker emulation code will need to know it. */
1329 if (*name == '\0')
1330 name = bfd_get_filename (abfd);
1331 elf_dt_name (abfd) = name;
1332 }
1333
1334 if (bfd_seek (abfd,
1335 hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym),
1336 SEEK_SET) != 0
1337 || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd)
1338 != extsymcount * sizeof (Elf_External_Sym)))
1339 goto error_return;
1340
1341 weaks = NULL;
1342
1343 ever = extversym != NULL ? extversym + extsymoff : NULL;
1344 esymend = buf + extsymcount;
1345 for (esym = buf;
1346 esym < esymend;
1347 esym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
1348 {
1349 Elf_Internal_Sym sym;
1350 int bind;
1351 bfd_vma value;
1352 asection *sec;
1353 flagword flags;
1354 const char *name;
1355 struct elf_link_hash_entry *h;
1356 boolean definition;
1357 boolean size_change_ok, type_change_ok;
1358 boolean new_weakdef;
1359 unsigned int old_alignment;
1360
1361 elf_swap_symbol_in (abfd, esym, &sym);
1362
1363 flags = BSF_NO_FLAGS;
1364 sec = NULL;
1365 value = sym.st_value;
1366 *sym_hash = NULL;
1367
1368 bind = ELF_ST_BIND (sym.st_info);
1369 if (bind == STB_LOCAL)
1370 {
1371 /* This should be impossible, since ELF requires that all
1372 global symbols follow all local symbols, and that sh_info
1373 point to the first global symbol. Unfortunatealy, Irix 5
1374 screws this up. */
1375 continue;
1376 }
1377 else if (bind == STB_GLOBAL)
1378 {
1379 if (sym.st_shndx != SHN_UNDEF
1380 && sym.st_shndx != SHN_COMMON)
1381 flags = BSF_GLOBAL;
1382 else
1383 flags = 0;
1384 }
1385 else if (bind == STB_WEAK)
1386 flags = BSF_WEAK;
1387 else
1388 {
1389 /* Leave it up to the processor backend. */
1390 }
1391
1392 if (sym.st_shndx == SHN_UNDEF)
1393 sec = bfd_und_section_ptr;
1394 else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE)
1395 {
1396 sec = section_from_elf_index (abfd, sym.st_shndx);
1397 if (sec == NULL)
1398 sec = bfd_abs_section_ptr;
1399 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1400 value -= sec->vma;
1401 }
1402 else if (sym.st_shndx == SHN_ABS)
1403 sec = bfd_abs_section_ptr;
1404 else if (sym.st_shndx == SHN_COMMON)
1405 {
1406 sec = bfd_com_section_ptr;
1407 /* What ELF calls the size we call the value. What ELF
1408 calls the value we call the alignment. */
1409 value = sym.st_size;
1410 }
1411 else
1412 {
1413 /* Leave it up to the processor backend. */
1414 }
1415
1416 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name);
1417 if (name == (const char *) NULL)
1418 goto error_return;
1419
1420 if (add_symbol_hook)
1421 {
1422 if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec,
1423 &value))
1424 goto error_return;
1425
1426 /* The hook function sets the name to NULL if this symbol
1427 should be skipped for some reason. */
1428 if (name == (const char *) NULL)
1429 continue;
1430 }
1431
1432 /* Sanity check that all possibilities were handled. */
1433 if (sec == (asection *) NULL)
1434 {
1435 bfd_set_error (bfd_error_bad_value);
1436 goto error_return;
1437 }
1438
1439 if (bfd_is_und_section (sec)
1440 || bfd_is_com_section (sec))
1441 definition = false;
1442 else
1443 definition = true;
1444
1445 size_change_ok = false;
1446 type_change_ok = get_elf_backend_data (abfd)->type_change_ok;
1447 old_alignment = 0;
1448 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1449 {
1450 Elf_Internal_Versym iver;
1451 unsigned int vernum = 0;
1452 boolean override;
1453
1454 if (ever != NULL)
1455 {
1456 _bfd_elf_swap_versym_in (abfd, ever, &iver);
1457 vernum = iver.vs_vers & VERSYM_VERSION;
1458
1459 /* If this is a hidden symbol, or if it is not version
1460 1, we append the version name to the symbol name.
1461 However, we do not modify a non-hidden absolute
1462 symbol, because it might be the version symbol
1463 itself. FIXME: What if it isn't? */
1464 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
1465 || (vernum > 1 && ! bfd_is_abs_section (sec)))
1466 {
1467 const char *verstr;
1468 int namelen, newlen;
1469 char *newname, *p;
1470
1471 if (sym.st_shndx != SHN_UNDEF)
1472 {
1473 if (vernum > elf_tdata (abfd)->dynverdef_hdr.sh_info)
1474 {
1475 (*_bfd_error_handler)
1476 (_("%s: %s: invalid version %u (max %d)"),
1477 bfd_get_filename (abfd), name, vernum,
1478 elf_tdata (abfd)->dynverdef_hdr.sh_info);
1479 bfd_set_error (bfd_error_bad_value);
1480 goto error_return;
1481 }
1482 else if (vernum > 1)
1483 verstr =
1484 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
1485 else
1486 verstr = "";
1487 }
1488 else
1489 {
1490 /* We cannot simply test for the number of
1491 entries in the VERNEED section since the
1492 numbers for the needed versions do not start
1493 at 0. */
1494 Elf_Internal_Verneed *t;
1495
1496 verstr = NULL;
1497 for (t = elf_tdata (abfd)->verref;
1498 t != NULL;
1499 t = t->vn_nextref)
1500 {
1501 Elf_Internal_Vernaux *a;
1502
1503 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1504 {
1505 if (a->vna_other == vernum)
1506 {
1507 verstr = a->vna_nodename;
1508 break;
1509 }
1510 }
1511 if (a != NULL)
1512 break;
1513 }
1514 if (verstr == NULL)
1515 {
1516 (*_bfd_error_handler)
1517 (_("%s: %s: invalid needed version %d"),
1518 bfd_get_filename (abfd), name, vernum);
1519 bfd_set_error (bfd_error_bad_value);
1520 goto error_return;
1521 }
1522 }
1523
1524 namelen = strlen (name);
1525 newlen = namelen + strlen (verstr) + 2;
1526 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
1527 ++newlen;
1528
1529 newname = (char *) bfd_alloc (abfd, newlen);
1530 if (newname == NULL)
1531 goto error_return;
1532 strcpy (newname, name);
1533 p = newname + namelen;
1534 *p++ = ELF_VER_CHR;
1535 /* If this is a defined non-hidden version symbol,
1536 we add another @ to the name. This indicates the
1537 default version of the symbol. */
1538 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
1539 && sym.st_shndx != SHN_UNDEF)
1540 *p++ = ELF_VER_CHR;
1541 strcpy (p, verstr);
1542
1543 name = newname;
1544 }
1545 }
1546
1547 if (! elf_merge_symbol (abfd, info, name, &sym, &sec, &value,
1548 sym_hash, &override, &type_change_ok,
1549 &size_change_ok, dt_needed))
1550 goto error_return;
1551
1552 if (override)
1553 definition = false;
1554
1555 h = *sym_hash;
1556 while (h->root.type == bfd_link_hash_indirect
1557 || h->root.type == bfd_link_hash_warning)
1558 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1559
1560 /* Remember the old alignment if this is a common symbol, so
1561 that we don't reduce the alignment later on. We can't
1562 check later, because _bfd_generic_link_add_one_symbol
1563 will set a default for the alignment which we want to
1564 override. */
1565 if (h->root.type == bfd_link_hash_common)
1566 old_alignment = h->root.u.c.p->alignment_power;
1567
1568 if (elf_tdata (abfd)->verdef != NULL
1569 && ! override
1570 && vernum > 1
1571 && definition)
1572 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
1573 }
1574
1575 if (! (_bfd_generic_link_add_one_symbol
1576 (info, abfd, name, flags, sec, value, (const char *) NULL,
1577 false, collect, (struct bfd_link_hash_entry **) sym_hash)))
1578 goto error_return;
1579
1580 h = *sym_hash;
1581 while (h->root.type == bfd_link_hash_indirect
1582 || h->root.type == bfd_link_hash_warning)
1583 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1584 *sym_hash = h;
1585
1586 new_weakdef = false;
1587 if (dynamic
1588 && definition
1589 && (flags & BSF_WEAK) != 0
1590 && ELF_ST_TYPE (sym.st_info) != STT_FUNC
1591 && info->hash->creator->flavour == bfd_target_elf_flavour
1592 && h->weakdef == NULL)
1593 {
1594 /* Keep a list of all weak defined non function symbols from
1595 a dynamic object, using the weakdef field. Later in this
1596 function we will set the weakdef field to the correct
1597 value. We only put non-function symbols from dynamic
1598 objects on this list, because that happens to be the only
1599 time we need to know the normal symbol corresponding to a
1600 weak symbol, and the information is time consuming to
1601 figure out. If the weakdef field is not already NULL,
1602 then this symbol was already defined by some previous
1603 dynamic object, and we will be using that previous
1604 definition anyhow. */
1605
1606 h->weakdef = weaks;
1607 weaks = h;
1608 new_weakdef = true;
1609 }
1610
1611 /* Set the alignment of a common symbol. */
1612 if (sym.st_shndx == SHN_COMMON
1613 && h->root.type == bfd_link_hash_common)
1614 {
1615 unsigned int align;
1616
1617 align = bfd_log2 (sym.st_value);
1618 if (align > old_alignment
1619 /* Permit an alignment power of zero if an alignment of one
1620 is specified and no other alignments have been specified. */
1621 || (sym.st_value == 1 && old_alignment == 0))
1622 h->root.u.c.p->alignment_power = align;
1623 }
1624
1625 if (info->hash->creator->flavour == bfd_target_elf_flavour)
1626 {
1627 int old_flags;
1628 boolean dynsym;
1629 int new_flag;
1630
1631 /* Remember the symbol size and type. */
1632 if (sym.st_size != 0
1633 && (definition || h->size == 0))
1634 {
1635 if (h->size != 0 && h->size != sym.st_size && ! size_change_ok)
1636 (*_bfd_error_handler)
1637 (_("Warning: size of symbol `%s' changed from %lu to %lu in %s"),
1638 name, (unsigned long) h->size, (unsigned long) sym.st_size,
1639 bfd_get_filename (abfd));
1640
1641 h->size = sym.st_size;
1642 }
1643
1644 /* If this is a common symbol, then we always want H->SIZE
1645 to be the size of the common symbol. The code just above
1646 won't fix the size if a common symbol becomes larger. We
1647 don't warn about a size change here, because that is
1648 covered by --warn-common. */
1649 if (h->root.type == bfd_link_hash_common)
1650 h->size = h->root.u.c.size;
1651
1652 if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE
1653 && (definition || h->type == STT_NOTYPE))
1654 {
1655 if (h->type != STT_NOTYPE
1656 && h->type != ELF_ST_TYPE (sym.st_info)
1657 && ! type_change_ok)
1658 (*_bfd_error_handler)
1659 (_("Warning: type of symbol `%s' changed from %d to %d in %s"),
1660 name, h->type, ELF_ST_TYPE (sym.st_info),
1661 bfd_get_filename (abfd));
1662
1663 h->type = ELF_ST_TYPE (sym.st_info);
1664 }
1665
1666 /* If st_other has a processor-specific meaning, specific code
1667 might be needed here. */
1668 if (sym.st_other != 0)
1669 {
1670 /* Combine visibilities, using the most constraining one. */
1671 unsigned char hvis = ELF_ST_VISIBILITY (h->other);
1672 unsigned char symvis = ELF_ST_VISIBILITY (sym.st_other);
1673
1674 if (symvis && (hvis > symvis || hvis == 0))
1675 h->other = sym.st_other;
1676
1677 /* If neither has visibility, use the st_other of the
1678 definition. This is an arbitrary choice, since the
1679 other bits have no general meaning. */
1680 if (!symvis && !hvis
1681 && (definition || h->other == 0))
1682 h->other = sym.st_other;
1683 }
1684
1685 /* Set a flag in the hash table entry indicating the type of
1686 reference or definition we just found. Keep a count of
1687 the number of dynamic symbols we find. A dynamic symbol
1688 is one which is referenced or defined by both a regular
1689 object and a shared object. */
1690 old_flags = h->elf_link_hash_flags;
1691 dynsym = false;
1692 if (! dynamic)
1693 {
1694 if (! definition)
1695 {
1696 new_flag = ELF_LINK_HASH_REF_REGULAR;
1697 if (bind != STB_WEAK)
1698 new_flag |= ELF_LINK_HASH_REF_REGULAR_NONWEAK;
1699 }
1700 else
1701 new_flag = ELF_LINK_HASH_DEF_REGULAR;
1702 if (info->shared
1703 || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC
1704 | ELF_LINK_HASH_REF_DYNAMIC)) != 0)
1705 dynsym = true;
1706 }
1707 else
1708 {
1709 if (! definition)
1710 new_flag = ELF_LINK_HASH_REF_DYNAMIC;
1711 else
1712 new_flag = ELF_LINK_HASH_DEF_DYNAMIC;
1713 if ((old_flags & (ELF_LINK_HASH_DEF_REGULAR
1714 | ELF_LINK_HASH_REF_REGULAR)) != 0
1715 || (h->weakdef != NULL
1716 && ! new_weakdef
1717 && h->weakdef->dynindx != -1))
1718 dynsym = true;
1719 }
1720
1721 h->elf_link_hash_flags |= new_flag;
1722
1723 /* If this symbol has a version, and it is the default
1724 version, we create an indirect symbol from the default
1725 name to the fully decorated name. This will cause
1726 external references which do not specify a version to be
1727 bound to this version of the symbol. */
1728 if (definition)
1729 {
1730 char *p;
1731
1732 p = strchr (name, ELF_VER_CHR);
1733 if (p != NULL && p[1] == ELF_VER_CHR)
1734 {
1735 char *shortname;
1736 struct elf_link_hash_entry *hi;
1737 boolean override;
1738
1739 shortname = bfd_hash_allocate (&info->hash->table,
1740 p - name + 1);
1741 if (shortname == NULL)
1742 goto error_return;
1743 strncpy (shortname, name, p - name);
1744 shortname[p - name] = '\0';
1745
1746 /* We are going to create a new symbol. Merge it
1747 with any existing symbol with this name. For the
1748 purposes of the merge, act as though we were
1749 defining the symbol we just defined, although we
1750 actually going to define an indirect symbol. */
1751 type_change_ok = false;
1752 size_change_ok = false;
1753 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1754 &value, &hi, &override,
1755 &type_change_ok,
1756 &size_change_ok, dt_needed))
1757 goto error_return;
1758
1759 if (! override)
1760 {
1761 if (! (_bfd_generic_link_add_one_symbol
1762 (info, abfd, shortname, BSF_INDIRECT,
1763 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1764 collect, (struct bfd_link_hash_entry **) &hi)))
1765 goto error_return;
1766 }
1767 else
1768 {
1769 /* In this case the symbol named SHORTNAME is
1770 overriding the indirect symbol we want to
1771 add. We were planning on making SHORTNAME an
1772 indirect symbol referring to NAME. SHORTNAME
1773 is the name without a version. NAME is the
1774 fully versioned name, and it is the default
1775 version.
1776
1777 Overriding means that we already saw a
1778 definition for the symbol SHORTNAME in a
1779 regular object, and it is overriding the
1780 symbol defined in the dynamic object.
1781
1782 When this happens, we actually want to change
1783 NAME, the symbol we just added, to refer to
1784 SHORTNAME. This will cause references to
1785 NAME in the shared object to become
1786 references to SHORTNAME in the regular
1787 object. This is what we expect when we
1788 override a function in a shared object: that
1789 the references in the shared object will be
1790 mapped to the definition in the regular
1791 object. */
1792
1793 while (hi->root.type == bfd_link_hash_indirect
1794 || hi->root.type == bfd_link_hash_warning)
1795 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1796
1797 h->root.type = bfd_link_hash_indirect;
1798 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1799 if (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC)
1800 {
1801 h->elf_link_hash_flags &=~ ELF_LINK_HASH_DEF_DYNAMIC;
1802 hi->elf_link_hash_flags |= ELF_LINK_HASH_REF_DYNAMIC;
1803 if (hi->elf_link_hash_flags
1804 & (ELF_LINK_HASH_REF_REGULAR
1805 | ELF_LINK_HASH_DEF_REGULAR))
1806 {
1807 if (! _bfd_elf_link_record_dynamic_symbol (info,
1808 hi))
1809 goto error_return;
1810 }
1811 }
1812
1813 /* Now set HI to H, so that the following code
1814 will set the other fields correctly. */
1815 hi = h;
1816 }
1817
1818 /* If there is a duplicate definition somewhere,
1819 then HI may not point to an indirect symbol. We
1820 will have reported an error to the user in that
1821 case. */
1822
1823 if (hi->root.type == bfd_link_hash_indirect)
1824 {
1825 struct elf_link_hash_entry *ht;
1826
1827 /* If the symbol became indirect, then we assume
1828 that we have not seen a definition before. */
1829 BFD_ASSERT ((hi->elf_link_hash_flags
1830 & (ELF_LINK_HASH_DEF_DYNAMIC
1831 | ELF_LINK_HASH_DEF_REGULAR))
1832 == 0);
1833
1834 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1835 (*bed->elf_backend_copy_indirect_symbol) (ht, hi);
1836
1837 /* See if the new flags lead us to realize that
1838 the symbol must be dynamic. */
1839 if (! dynsym)
1840 {
1841 if (! dynamic)
1842 {
1843 if (info->shared
1844 || ((hi->elf_link_hash_flags
1845 & ELF_LINK_HASH_REF_DYNAMIC)
1846 != 0))
1847 dynsym = true;
1848 }
1849 else
1850 {
1851 if ((hi->elf_link_hash_flags
1852 & ELF_LINK_HASH_REF_REGULAR) != 0)
1853 dynsym = true;
1854 }
1855 }
1856 }
1857
1858 /* We also need to define an indirection from the
1859 nondefault version of the symbol. */
1860
1861 shortname = bfd_hash_allocate (&info->hash->table,
1862 strlen (name));
1863 if (shortname == NULL)
1864 goto error_return;
1865 strncpy (shortname, name, p - name);
1866 strcpy (shortname + (p - name), p + 1);
1867
1868 /* Once again, merge with any existing symbol. */
1869 type_change_ok = false;
1870 size_change_ok = false;
1871 if (! elf_merge_symbol (abfd, info, shortname, &sym, &sec,
1872 &value, &hi, &override,
1873 &type_change_ok,
1874 &size_change_ok, dt_needed))
1875 goto error_return;
1876
1877 if (override)
1878 {
1879 /* Here SHORTNAME is a versioned name, so we
1880 don't expect to see the type of override we
1881 do in the case above. */
1882 (*_bfd_error_handler)
1883 (_("%s: warning: unexpected redefinition of `%s'"),
1884 bfd_get_filename (abfd), shortname);
1885 }
1886 else
1887 {
1888 if (! (_bfd_generic_link_add_one_symbol
1889 (info, abfd, shortname, BSF_INDIRECT,
1890 bfd_ind_section_ptr, (bfd_vma) 0, name, false,
1891 collect, (struct bfd_link_hash_entry **) &hi)))
1892 goto error_return;
1893
1894 /* If there is a duplicate definition somewhere,
1895 then HI may not point to an indirect symbol.
1896 We will have reported an error to the user in
1897 that case. */
1898
1899 if (hi->root.type == bfd_link_hash_indirect)
1900 {
1901 /* If the symbol became indirect, then we
1902 assume that we have not seen a definition
1903 before. */
1904 BFD_ASSERT ((hi->elf_link_hash_flags
1905 & (ELF_LINK_HASH_DEF_DYNAMIC
1906 | ELF_LINK_HASH_DEF_REGULAR))
1907 == 0);
1908
1909 (*bed->elf_backend_copy_indirect_symbol) (h, hi);
1910
1911 /* See if the new flags lead us to realize
1912 that the symbol must be dynamic. */
1913 if (! dynsym)
1914 {
1915 if (! dynamic)
1916 {
1917 if (info->shared
1918 || ((hi->elf_link_hash_flags
1919 & ELF_LINK_HASH_REF_DYNAMIC)
1920 != 0))
1921 dynsym = true;
1922 }
1923 else
1924 {
1925 if ((hi->elf_link_hash_flags
1926 & ELF_LINK_HASH_REF_REGULAR) != 0)
1927 dynsym = true;
1928 }
1929 }
1930 }
1931 }
1932 }
1933 }
1934
1935 if (dynsym && h->dynindx == -1)
1936 {
1937 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
1938 goto error_return;
1939 if (h->weakdef != NULL
1940 && ! new_weakdef
1941 && h->weakdef->dynindx == -1)
1942 {
1943 if (! _bfd_elf_link_record_dynamic_symbol (info,
1944 h->weakdef))
1945 goto error_return;
1946 }
1947 }
1948 else if (dynsym && h->dynindx != -1)
1949 /* If the symbol already has a dynamic index, but
1950 visibility says it should not be visible, turn it into
1951 a local symbol. */
1952 switch (ELF_ST_VISIBILITY (h->other))
1953 {
1954 case STV_INTERNAL:
1955 case STV_HIDDEN:
1956 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
1957 (*bed->elf_backend_hide_symbol) (info, h);
1958 break;
1959 }
1960
1961 if (dt_needed && definition
1962 && (h->elf_link_hash_flags
1963 & ELF_LINK_HASH_REF_REGULAR) != 0)
1964 {
1965 bfd_size_type oldsize;
1966 bfd_size_type strindex;
1967
1968 /* The symbol from a DT_NEEDED object is referenced from
1969 the regular object to create a dynamic executable. We
1970 have to make sure there is a DT_NEEDED entry for it. */
1971
1972 dt_needed = false;
1973 oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
1974 strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
1975 elf_dt_soname (abfd),
1976 true, false);
1977 if (strindex == (bfd_size_type) -1)
1978 goto error_return;
1979
1980 if (oldsize
1981 == _bfd_stringtab_size (elf_hash_table (info)->dynstr))
1982 {
1983 asection *sdyn;
1984 Elf_External_Dyn *dyncon, *dynconend;
1985
1986 sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
1987 ".dynamic");
1988 BFD_ASSERT (sdyn != NULL);
1989
1990 dyncon = (Elf_External_Dyn *) sdyn->contents;
1991 dynconend = (Elf_External_Dyn *) (sdyn->contents +
1992 sdyn->_raw_size);
1993 for (; dyncon < dynconend; dyncon++)
1994 {
1995 Elf_Internal_Dyn dyn;
1996
1997 elf_swap_dyn_in (elf_hash_table (info)->dynobj,
1998 dyncon, &dyn);
1999 BFD_ASSERT (dyn.d_tag != DT_NEEDED ||
2000 dyn.d_un.d_val != strindex);
2001 }
2002 }
2003
2004 if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2005 goto error_return;
2006 }
2007 }
2008 }
2009
2010 /* Now set the weakdefs field correctly for all the weak defined
2011 symbols we found. The only way to do this is to search all the
2012 symbols. Since we only need the information for non functions in
2013 dynamic objects, that's the only time we actually put anything on
2014 the list WEAKS. We need this information so that if a regular
2015 object refers to a symbol defined weakly in a dynamic object, the
2016 real symbol in the dynamic object is also put in the dynamic
2017 symbols; we also must arrange for both symbols to point to the
2018 same memory location. We could handle the general case of symbol
2019 aliasing, but a general symbol alias can only be generated in
2020 assembler code, handling it correctly would be very time
2021 consuming, and other ELF linkers don't handle general aliasing
2022 either. */
2023 while (weaks != NULL)
2024 {
2025 struct elf_link_hash_entry *hlook;
2026 asection *slook;
2027 bfd_vma vlook;
2028 struct elf_link_hash_entry **hpp;
2029 struct elf_link_hash_entry **hppend;
2030
2031 hlook = weaks;
2032 weaks = hlook->weakdef;
2033 hlook->weakdef = NULL;
2034
2035 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
2036 || hlook->root.type == bfd_link_hash_defweak
2037 || hlook->root.type == bfd_link_hash_common
2038 || hlook->root.type == bfd_link_hash_indirect);
2039 slook = hlook->root.u.def.section;
2040 vlook = hlook->root.u.def.value;
2041
2042 hpp = elf_sym_hashes (abfd);
2043 hppend = hpp + extsymcount;
2044 for (; hpp < hppend; hpp++)
2045 {
2046 struct elf_link_hash_entry *h;
2047
2048 h = *hpp;
2049 if (h != NULL && h != hlook
2050 && h->root.type == bfd_link_hash_defined
2051 && h->root.u.def.section == slook
2052 && h->root.u.def.value == vlook)
2053 {
2054 hlook->weakdef = h;
2055
2056 /* If the weak definition is in the list of dynamic
2057 symbols, make sure the real definition is put there
2058 as well. */
2059 if (hlook->dynindx != -1
2060 && h->dynindx == -1)
2061 {
2062 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2063 goto error_return;
2064 }
2065
2066 /* If the real definition is in the list of dynamic
2067 symbols, make sure the weak definition is put there
2068 as well. If we don't do this, then the dynamic
2069 loader might not merge the entries for the real
2070 definition and the weak definition. */
2071 if (h->dynindx != -1
2072 && hlook->dynindx == -1)
2073 {
2074 if (! _bfd_elf_link_record_dynamic_symbol (info, hlook))
2075 goto error_return;
2076 }
2077
2078 break;
2079 }
2080 }
2081 }
2082
2083 if (buf != NULL)
2084 {
2085 free (buf);
2086 buf = NULL;
2087 }
2088
2089 if (extversym != NULL)
2090 {
2091 free (extversym);
2092 extversym = NULL;
2093 }
2094
2095 /* If this object is the same format as the output object, and it is
2096 not a shared library, then let the backend look through the
2097 relocs.
2098
2099 This is required to build global offset table entries and to
2100 arrange for dynamic relocs. It is not required for the
2101 particular common case of linking non PIC code, even when linking
2102 against shared libraries, but unfortunately there is no way of
2103 knowing whether an object file has been compiled PIC or not.
2104 Looking through the relocs is not particularly time consuming.
2105 The problem is that we must either (1) keep the relocs in memory,
2106 which causes the linker to require additional runtime memory or
2107 (2) read the relocs twice from the input file, which wastes time.
2108 This would be a good case for using mmap.
2109
2110 I have no idea how to handle linking PIC code into a file of a
2111 different format. It probably can't be done. */
2112 check_relocs = get_elf_backend_data (abfd)->check_relocs;
2113 if (! dynamic
2114 && abfd->xvec == info->hash->creator
2115 && check_relocs != NULL)
2116 {
2117 asection *o;
2118
2119 for (o = abfd->sections; o != NULL; o = o->next)
2120 {
2121 Elf_Internal_Rela *internal_relocs;
2122 boolean ok;
2123
2124 if ((o->flags & SEC_RELOC) == 0
2125 || o->reloc_count == 0
2126 || ((info->strip == strip_all || info->strip == strip_debugger)
2127 && (o->flags & SEC_DEBUGGING) != 0)
2128 || bfd_is_abs_section (o->output_section))
2129 continue;
2130
2131 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
2132 (abfd, o, (PTR) NULL,
2133 (Elf_Internal_Rela *) NULL,
2134 info->keep_memory));
2135 if (internal_relocs == NULL)
2136 goto error_return;
2137
2138 ok = (*check_relocs) (abfd, info, o, internal_relocs);
2139
2140 if (! info->keep_memory)
2141 free (internal_relocs);
2142
2143 if (! ok)
2144 goto error_return;
2145 }
2146 }
2147
2148 /* If this is a non-traditional, non-relocateable link, try to
2149 optimize the handling of the .stab/.stabstr sections. */
2150 if (! dynamic
2151 && ! info->relocateable
2152 && ! info->traditional_format
2153 && info->hash->creator->flavour == bfd_target_elf_flavour
2154 && (info->strip != strip_all && info->strip != strip_debugger))
2155 {
2156 asection *stab, *stabstr;
2157
2158 stab = bfd_get_section_by_name (abfd, ".stab");
2159 if (stab != NULL)
2160 {
2161 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
2162
2163 if (stabstr != NULL)
2164 {
2165 struct bfd_elf_section_data *secdata;
2166
2167 secdata = elf_section_data (stab);
2168 if (! _bfd_link_section_stabs (abfd,
2169 &elf_hash_table (info)->stab_info,
2170 stab, stabstr,
2171 &secdata->stab_info))
2172 goto error_return;
2173 }
2174 }
2175 }
2176
2177 return true;
2178
2179 error_return:
2180 if (buf != NULL)
2181 free (buf);
2182 if (dynbuf != NULL)
2183 free (dynbuf);
2184 if (dynver != NULL)
2185 free (dynver);
2186 if (extversym != NULL)
2187 free (extversym);
2188 return false;
2189 }
2190
2191 /* Create some sections which will be filled in with dynamic linking
2192 information. ABFD is an input file which requires dynamic sections
2193 to be created. The dynamic sections take up virtual memory space
2194 when the final executable is run, so we need to create them before
2195 addresses are assigned to the output sections. We work out the
2196 actual contents and size of these sections later. */
2197
2198 boolean
2199 elf_link_create_dynamic_sections (abfd, info)
2200 bfd *abfd;
2201 struct bfd_link_info *info;
2202 {
2203 flagword flags;
2204 register asection *s;
2205 struct elf_link_hash_entry *h;
2206 struct elf_backend_data *bed;
2207
2208 if (elf_hash_table (info)->dynamic_sections_created)
2209 return true;
2210
2211 /* Make sure that all dynamic sections use the same input BFD. */
2212 if (elf_hash_table (info)->dynobj == NULL)
2213 elf_hash_table (info)->dynobj = abfd;
2214 else
2215 abfd = elf_hash_table (info)->dynobj;
2216
2217 /* Note that we set the SEC_IN_MEMORY flag for all of these
2218 sections. */
2219 flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
2220 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
2221
2222 /* A dynamically linked executable has a .interp section, but a
2223 shared library does not. */
2224 if (! info->shared)
2225 {
2226 s = bfd_make_section (abfd, ".interp");
2227 if (s == NULL
2228 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2229 return false;
2230 }
2231
2232 /* Create sections to hold version informations. These are removed
2233 if they are not needed. */
2234 s = bfd_make_section (abfd, ".gnu.version_d");
2235 if (s == NULL
2236 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2237 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2238 return false;
2239
2240 s = bfd_make_section (abfd, ".gnu.version");
2241 if (s == NULL
2242 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2243 || ! bfd_set_section_alignment (abfd, s, 1))
2244 return false;
2245
2246 s = bfd_make_section (abfd, ".gnu.version_r");
2247 if (s == NULL
2248 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2249 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2250 return false;
2251
2252 s = bfd_make_section (abfd, ".dynsym");
2253 if (s == NULL
2254 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2255 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2256 return false;
2257
2258 s = bfd_make_section (abfd, ".dynstr");
2259 if (s == NULL
2260 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY))
2261 return false;
2262
2263 /* Create a strtab to hold the dynamic symbol names. */
2264 if (elf_hash_table (info)->dynstr == NULL)
2265 {
2266 elf_hash_table (info)->dynstr = elf_stringtab_init ();
2267 if (elf_hash_table (info)->dynstr == NULL)
2268 return false;
2269 }
2270
2271 s = bfd_make_section (abfd, ".dynamic");
2272 if (s == NULL
2273 || ! bfd_set_section_flags (abfd, s, flags)
2274 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2275 return false;
2276
2277 /* The special symbol _DYNAMIC is always set to the start of the
2278 .dynamic section. This call occurs before we have processed the
2279 symbols for any dynamic object, so we don't have to worry about
2280 overriding a dynamic definition. We could set _DYNAMIC in a
2281 linker script, but we only want to define it if we are, in fact,
2282 creating a .dynamic section. We don't want to define it if there
2283 is no .dynamic section, since on some ELF platforms the start up
2284 code examines it to decide how to initialize the process. */
2285 h = NULL;
2286 if (! (_bfd_generic_link_add_one_symbol
2287 (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0,
2288 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
2289 (struct bfd_link_hash_entry **) &h)))
2290 return false;
2291 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2292 h->type = STT_OBJECT;
2293
2294 if (info->shared
2295 && ! _bfd_elf_link_record_dynamic_symbol (info, h))
2296 return false;
2297
2298 bed = get_elf_backend_data (abfd);
2299
2300 s = bfd_make_section (abfd, ".hash");
2301 if (s == NULL
2302 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
2303 || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN))
2304 return false;
2305 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
2306
2307 /* Let the backend create the rest of the sections. This lets the
2308 backend set the right flags. The backend will normally create
2309 the .got and .plt sections. */
2310 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
2311 return false;
2312
2313 elf_hash_table (info)->dynamic_sections_created = true;
2314
2315 return true;
2316 }
2317
2318 /* Add an entry to the .dynamic table. */
2319
2320 boolean
2321 elf_add_dynamic_entry (info, tag, val)
2322 struct bfd_link_info *info;
2323 bfd_vma tag;
2324 bfd_vma val;
2325 {
2326 Elf_Internal_Dyn dyn;
2327 bfd *dynobj;
2328 asection *s;
2329 size_t newsize;
2330 bfd_byte *newcontents;
2331
2332 dynobj = elf_hash_table (info)->dynobj;
2333
2334 s = bfd_get_section_by_name (dynobj, ".dynamic");
2335 BFD_ASSERT (s != NULL);
2336
2337 newsize = s->_raw_size + sizeof (Elf_External_Dyn);
2338 newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
2339 if (newcontents == NULL)
2340 return false;
2341
2342 dyn.d_tag = tag;
2343 dyn.d_un.d_val = val;
2344 elf_swap_dyn_out (dynobj, &dyn,
2345 (Elf_External_Dyn *) (newcontents + s->_raw_size));
2346
2347 s->_raw_size = newsize;
2348 s->contents = newcontents;
2349
2350 return true;
2351 }
2352
2353 /* Record a new local dynamic symbol. */
2354
2355 boolean
2356 elf_link_record_local_dynamic_symbol (info, input_bfd, input_indx)
2357 struct bfd_link_info *info;
2358 bfd *input_bfd;
2359 long input_indx;
2360 {
2361 struct elf_link_local_dynamic_entry *entry;
2362 struct elf_link_hash_table *eht;
2363 struct bfd_strtab_hash *dynstr;
2364 Elf_External_Sym esym;
2365 unsigned long dynstr_index;
2366 char *name;
2367
2368 /* See if the entry exists already. */
2369 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
2370 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
2371 return true;
2372
2373 entry = (struct elf_link_local_dynamic_entry *)
2374 bfd_alloc (input_bfd, sizeof (*entry));
2375 if (entry == NULL)
2376 return false;
2377
2378 /* Go find the symbol, so that we can find it's name. */
2379 if (bfd_seek (input_bfd,
2380 (elf_tdata (input_bfd)->symtab_hdr.sh_offset
2381 + input_indx * sizeof (Elf_External_Sym)),
2382 SEEK_SET) != 0
2383 || (bfd_read (&esym, sizeof (Elf_External_Sym), 1, input_bfd)
2384 != sizeof (Elf_External_Sym)))
2385 return false;
2386 elf_swap_symbol_in (input_bfd, &esym, &entry->isym);
2387
2388 name = (bfd_elf_string_from_elf_section
2389 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
2390 entry->isym.st_name));
2391
2392 dynstr = elf_hash_table (info)->dynstr;
2393 if (dynstr == NULL)
2394 {
2395 /* Create a strtab to hold the dynamic symbol names. */
2396 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_stringtab_init ();
2397 if (dynstr == NULL)
2398 return false;
2399 }
2400
2401 dynstr_index = _bfd_stringtab_add (dynstr, name, true, false);
2402 if (dynstr_index == (unsigned long) -1)
2403 return false;
2404 entry->isym.st_name = dynstr_index;
2405
2406 eht = elf_hash_table (info);
2407
2408 entry->next = eht->dynlocal;
2409 eht->dynlocal = entry;
2410 entry->input_bfd = input_bfd;
2411 entry->input_indx = input_indx;
2412 eht->dynsymcount++;
2413
2414 /* Whatever binding the symbol had before, it's now local. */
2415 entry->isym.st_info
2416 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
2417
2418 /* The dynindx will be set at the end of size_dynamic_sections. */
2419
2420 return true;
2421 }
2422 \f
2423
2424 /* Read and swap the relocs from the section indicated by SHDR. This
2425 may be either a REL or a RELA section. The relocations are
2426 translated into RELA relocations and stored in INTERNAL_RELOCS,
2427 which should have already been allocated to contain enough space.
2428 The EXTERNAL_RELOCS are a buffer where the external form of the
2429 relocations should be stored.
2430
2431 Returns false if something goes wrong. */
2432
2433 static boolean
2434 elf_link_read_relocs_from_section (abfd, shdr, external_relocs,
2435 internal_relocs)
2436 bfd *abfd;
2437 Elf_Internal_Shdr *shdr;
2438 PTR external_relocs;
2439 Elf_Internal_Rela *internal_relocs;
2440 {
2441 struct elf_backend_data *bed;
2442
2443 /* If there aren't any relocations, that's OK. */
2444 if (!shdr)
2445 return true;
2446
2447 /* Position ourselves at the start of the section. */
2448 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2449 return false;
2450
2451 /* Read the relocations. */
2452 if (bfd_read (external_relocs, 1, shdr->sh_size, abfd)
2453 != shdr->sh_size)
2454 return false;
2455
2456 bed = get_elf_backend_data (abfd);
2457
2458 /* Convert the external relocations to the internal format. */
2459 if (shdr->sh_entsize == sizeof (Elf_External_Rel))
2460 {
2461 Elf_External_Rel *erel;
2462 Elf_External_Rel *erelend;
2463 Elf_Internal_Rela *irela;
2464 Elf_Internal_Rel *irel;
2465
2466 erel = (Elf_External_Rel *) external_relocs;
2467 erelend = erel + shdr->sh_size / shdr->sh_entsize;
2468 irela = internal_relocs;
2469 irel = bfd_alloc (abfd, (bed->s->int_rels_per_ext_rel
2470 * sizeof (Elf_Internal_Rel)));
2471 for (; erel < erelend; erel++, irela += bed->s->int_rels_per_ext_rel)
2472 {
2473 unsigned char i;
2474
2475 if (bed->s->swap_reloc_in)
2476 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, irel);
2477 else
2478 elf_swap_reloc_in (abfd, erel, irel);
2479
2480 for (i = 0; i < bed->s->int_rels_per_ext_rel; ++i)
2481 {
2482 irela[i].r_offset = irel[i].r_offset;
2483 irela[i].r_info = irel[i].r_info;
2484 irela[i].r_addend = 0;
2485 }
2486 }
2487 }
2488 else
2489 {
2490 Elf_External_Rela *erela;
2491 Elf_External_Rela *erelaend;
2492 Elf_Internal_Rela *irela;
2493
2494 BFD_ASSERT (shdr->sh_entsize == sizeof (Elf_External_Rela));
2495
2496 erela = (Elf_External_Rela *) external_relocs;
2497 erelaend = erela + shdr->sh_size / shdr->sh_entsize;
2498 irela = internal_relocs;
2499 for (; erela < erelaend; erela++, irela += bed->s->int_rels_per_ext_rel)
2500 {
2501 if (bed->s->swap_reloca_in)
2502 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, irela);
2503 else
2504 elf_swap_reloca_in (abfd, erela, irela);
2505 }
2506 }
2507
2508 return true;
2509 }
2510
2511 /* Read and swap the relocs for a section O. They may have been
2512 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2513 not NULL, they are used as buffers to read into. They are known to
2514 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2515 the return value is allocated using either malloc or bfd_alloc,
2516 according to the KEEP_MEMORY argument. If O has two relocation
2517 sections (both REL and RELA relocations), then the REL_HDR
2518 relocations will appear first in INTERNAL_RELOCS, followed by the
2519 REL_HDR2 relocations. */
2520
2521 Elf_Internal_Rela *
2522 NAME(_bfd_elf,link_read_relocs) (abfd, o, external_relocs, internal_relocs,
2523 keep_memory)
2524 bfd *abfd;
2525 asection *o;
2526 PTR external_relocs;
2527 Elf_Internal_Rela *internal_relocs;
2528 boolean keep_memory;
2529 {
2530 Elf_Internal_Shdr *rel_hdr;
2531 PTR alloc1 = NULL;
2532 Elf_Internal_Rela *alloc2 = NULL;
2533 struct elf_backend_data *bed = get_elf_backend_data (abfd);
2534
2535 if (elf_section_data (o)->relocs != NULL)
2536 return elf_section_data (o)->relocs;
2537
2538 if (o->reloc_count == 0)
2539 return NULL;
2540
2541 rel_hdr = &elf_section_data (o)->rel_hdr;
2542
2543 if (internal_relocs == NULL)
2544 {
2545 size_t size;
2546
2547 size = (o->reloc_count * bed->s->int_rels_per_ext_rel
2548 * sizeof (Elf_Internal_Rela));
2549 if (keep_memory)
2550 internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2551 else
2552 internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2553 if (internal_relocs == NULL)
2554 goto error_return;
2555 }
2556
2557 if (external_relocs == NULL)
2558 {
2559 size_t size = (size_t) rel_hdr->sh_size;
2560
2561 if (elf_section_data (o)->rel_hdr2)
2562 size += (size_t) elf_section_data (o)->rel_hdr2->sh_size;
2563 alloc1 = (PTR) bfd_malloc (size);
2564 if (alloc1 == NULL)
2565 goto error_return;
2566 external_relocs = alloc1;
2567 }
2568
2569 if (!elf_link_read_relocs_from_section (abfd, rel_hdr,
2570 external_relocs,
2571 internal_relocs))
2572 goto error_return;
2573 if (!elf_link_read_relocs_from_section
2574 (abfd,
2575 elf_section_data (o)->rel_hdr2,
2576 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2577 internal_relocs + (rel_hdr->sh_size / rel_hdr->sh_entsize
2578 * bed->s->int_rels_per_ext_rel)))
2579 goto error_return;
2580
2581 /* Cache the results for next time, if we can. */
2582 if (keep_memory)
2583 elf_section_data (o)->relocs = internal_relocs;
2584
2585 if (alloc1 != NULL)
2586 free (alloc1);
2587
2588 /* Don't free alloc2, since if it was allocated we are passing it
2589 back (under the name of internal_relocs). */
2590
2591 return internal_relocs;
2592
2593 error_return:
2594 if (alloc1 != NULL)
2595 free (alloc1);
2596 if (alloc2 != NULL)
2597 free (alloc2);
2598 return NULL;
2599 }
2600 \f
2601
2602 /* Record an assignment to a symbol made by a linker script. We need
2603 this in case some dynamic object refers to this symbol. */
2604
2605 /*ARGSUSED*/
2606 boolean
2607 NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide)
2608 bfd *output_bfd ATTRIBUTE_UNUSED;
2609 struct bfd_link_info *info;
2610 const char *name;
2611 boolean provide;
2612 {
2613 struct elf_link_hash_entry *h;
2614
2615 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2616 return true;
2617
2618 h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false);
2619 if (h == NULL)
2620 return false;
2621
2622 if (h->root.type == bfd_link_hash_new)
2623 h->elf_link_hash_flags &=~ ELF_LINK_NON_ELF;
2624
2625 /* If this symbol is being provided by the linker script, and it is
2626 currently defined by a dynamic object, but not by a regular
2627 object, then mark it as undefined so that the generic linker will
2628 force the correct value. */
2629 if (provide
2630 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2631 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2632 h->root.type = bfd_link_hash_undefined;
2633
2634 /* If this symbol is not being provided by the linker script, and it is
2635 currently defined by a dynamic object, but not by a regular object,
2636 then clear out any version information because the symbol will not be
2637 associated with the dynamic object any more. */
2638 if (!provide
2639 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2640 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2641 h->verinfo.verdef = NULL;
2642
2643 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
2644
2645 /* When possible, keep the original type of the symbol */
2646 if (h->type == STT_NOTYPE)
2647 h->type = STT_OBJECT;
2648
2649 if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC
2650 | ELF_LINK_HASH_REF_DYNAMIC)) != 0
2651 || info->shared)
2652 && h->dynindx == -1)
2653 {
2654 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
2655 return false;
2656
2657 /* If this is a weak defined symbol, and we know a corresponding
2658 real symbol from the same dynamic object, make sure the real
2659 symbol is also made into a dynamic symbol. */
2660 if (h->weakdef != NULL
2661 && h->weakdef->dynindx == -1)
2662 {
2663 if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef))
2664 return false;
2665 }
2666 }
2667
2668 return true;
2669 }
2670 \f
2671 /* This structure is used to pass information to
2672 elf_link_assign_sym_version. */
2673
2674 struct elf_assign_sym_version_info
2675 {
2676 /* Output BFD. */
2677 bfd *output_bfd;
2678 /* General link information. */
2679 struct bfd_link_info *info;
2680 /* Version tree. */
2681 struct bfd_elf_version_tree *verdefs;
2682 /* Whether we are exporting all dynamic symbols. */
2683 boolean export_dynamic;
2684 /* Whether we had a failure. */
2685 boolean failed;
2686 };
2687
2688 /* This structure is used to pass information to
2689 elf_link_find_version_dependencies. */
2690
2691 struct elf_find_verdep_info
2692 {
2693 /* Output BFD. */
2694 bfd *output_bfd;
2695 /* General link information. */
2696 struct bfd_link_info *info;
2697 /* The number of dependencies. */
2698 unsigned int vers;
2699 /* Whether we had a failure. */
2700 boolean failed;
2701 };
2702
2703 /* Array used to determine the number of hash table buckets to use
2704 based on the number of symbols there are. If there are fewer than
2705 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
2706 fewer than 37 we use 17 buckets, and so forth. We never use more
2707 than 32771 buckets. */
2708
2709 static const size_t elf_buckets[] =
2710 {
2711 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
2712 16411, 32771, 0
2713 };
2714
2715 /* Compute bucket count for hashing table. We do not use a static set
2716 of possible tables sizes anymore. Instead we determine for all
2717 possible reasonable sizes of the table the outcome (i.e., the
2718 number of collisions etc) and choose the best solution. The
2719 weighting functions are not too simple to allow the table to grow
2720 without bounds. Instead one of the weighting factors is the size.
2721 Therefore the result is always a good payoff between few collisions
2722 (= short chain lengths) and table size. */
2723 static size_t
2724 compute_bucket_count (info)
2725 struct bfd_link_info *info;
2726 {
2727 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
2728 size_t best_size = 0;
2729 unsigned long int *hashcodes;
2730 unsigned long int *hashcodesp;
2731 unsigned long int i;
2732
2733 /* Compute the hash values for all exported symbols. At the same
2734 time store the values in an array so that we could use them for
2735 optimizations. */
2736 hashcodes = (unsigned long int *) bfd_malloc (dynsymcount
2737 * sizeof (unsigned long int));
2738 if (hashcodes == NULL)
2739 return 0;
2740 hashcodesp = hashcodes;
2741
2742 /* Put all hash values in HASHCODES. */
2743 elf_link_hash_traverse (elf_hash_table (info),
2744 elf_collect_hash_codes, &hashcodesp);
2745
2746 /* We have a problem here. The following code to optimize the table
2747 size requires an integer type with more the 32 bits. If
2748 BFD_HOST_U_64_BIT is set we know about such a type. */
2749 #ifdef BFD_HOST_U_64_BIT
2750 if (info->optimize == true)
2751 {
2752 unsigned long int nsyms = hashcodesp - hashcodes;
2753 size_t minsize;
2754 size_t maxsize;
2755 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
2756 unsigned long int *counts ;
2757
2758 /* Possible optimization parameters: if we have NSYMS symbols we say
2759 that the hashing table must at least have NSYMS/4 and at most
2760 2*NSYMS buckets. */
2761 minsize = nsyms / 4;
2762 if (minsize == 0)
2763 minsize = 1;
2764 best_size = maxsize = nsyms * 2;
2765
2766 /* Create array where we count the collisions in. We must use bfd_malloc
2767 since the size could be large. */
2768 counts = (unsigned long int *) bfd_malloc (maxsize
2769 * sizeof (unsigned long int));
2770 if (counts == NULL)
2771 {
2772 free (hashcodes);
2773 return 0;
2774 }
2775
2776 /* Compute the "optimal" size for the hash table. The criteria is a
2777 minimal chain length. The minor criteria is (of course) the size
2778 of the table. */
2779 for (i = minsize; i < maxsize; ++i)
2780 {
2781 /* Walk through the array of hashcodes and count the collisions. */
2782 BFD_HOST_U_64_BIT max;
2783 unsigned long int j;
2784 unsigned long int fact;
2785
2786 memset (counts, '\0', i * sizeof (unsigned long int));
2787
2788 /* Determine how often each hash bucket is used. */
2789 for (j = 0; j < nsyms; ++j)
2790 ++counts[hashcodes[j] % i];
2791
2792 /* For the weight function we need some information about the
2793 pagesize on the target. This is information need not be 100%
2794 accurate. Since this information is not available (so far) we
2795 define it here to a reasonable default value. If it is crucial
2796 to have a better value some day simply define this value. */
2797 # ifndef BFD_TARGET_PAGESIZE
2798 # define BFD_TARGET_PAGESIZE (4096)
2799 # endif
2800
2801 /* We in any case need 2 + NSYMS entries for the size values and
2802 the chains. */
2803 max = (2 + nsyms) * (ARCH_SIZE / 8);
2804
2805 # if 1
2806 /* Variant 1: optimize for short chains. We add the squares
2807 of all the chain lengths (which favous many small chain
2808 over a few long chains). */
2809 for (j = 0; j < i; ++j)
2810 max += counts[j] * counts[j];
2811
2812 /* This adds penalties for the overall size of the table. */
2813 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2814 max *= fact * fact;
2815 # else
2816 /* Variant 2: Optimize a lot more for small table. Here we
2817 also add squares of the size but we also add penalties for
2818 empty slots (the +1 term). */
2819 for (j = 0; j < i; ++j)
2820 max += (1 + counts[j]) * (1 + counts[j]);
2821
2822 /* The overall size of the table is considered, but not as
2823 strong as in variant 1, where it is squared. */
2824 fact = i / (BFD_TARGET_PAGESIZE / (ARCH_SIZE / 8)) + 1;
2825 max *= fact;
2826 # endif
2827
2828 /* Compare with current best results. */
2829 if (max < best_chlen)
2830 {
2831 best_chlen = max;
2832 best_size = i;
2833 }
2834 }
2835
2836 free (counts);
2837 }
2838 else
2839 #endif /* defined (BFD_HOST_U_64_BIT) */
2840 {
2841 /* This is the fallback solution if no 64bit type is available or if we
2842 are not supposed to spend much time on optimizations. We select the
2843 bucket count using a fixed set of numbers. */
2844 for (i = 0; elf_buckets[i] != 0; i++)
2845 {
2846 best_size = elf_buckets[i];
2847 if (dynsymcount < elf_buckets[i + 1])
2848 break;
2849 }
2850 }
2851
2852 /* Free the arrays we needed. */
2853 free (hashcodes);
2854
2855 return best_size;
2856 }
2857
2858 /* Set up the sizes and contents of the ELF dynamic sections. This is
2859 called by the ELF linker emulation before_allocation routine. We
2860 must set the sizes of the sections before the linker sets the
2861 addresses of the various sections. */
2862
2863 boolean
2864 NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath,
2865 export_dynamic, filter_shlib,
2866 auxiliary_filters, info, sinterpptr,
2867 verdefs)
2868 bfd *output_bfd;
2869 const char *soname;
2870 const char *rpath;
2871 boolean export_dynamic;
2872 const char *filter_shlib;
2873 const char * const *auxiliary_filters;
2874 struct bfd_link_info *info;
2875 asection **sinterpptr;
2876 struct bfd_elf_version_tree *verdefs;
2877 {
2878 bfd_size_type soname_indx;
2879 bfd *dynobj;
2880 struct elf_backend_data *bed;
2881 struct elf_assign_sym_version_info asvinfo;
2882
2883 *sinterpptr = NULL;
2884
2885 soname_indx = (bfd_size_type) -1;
2886
2887 if (info->hash->creator->flavour != bfd_target_elf_flavour)
2888 return true;
2889
2890 /* The backend may have to create some sections regardless of whether
2891 we're dynamic or not. */
2892 bed = get_elf_backend_data (output_bfd);
2893 if (bed->elf_backend_always_size_sections
2894 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
2895 return false;
2896
2897 dynobj = elf_hash_table (info)->dynobj;
2898
2899 /* If there were no dynamic objects in the link, there is nothing to
2900 do here. */
2901 if (dynobj == NULL)
2902 return true;
2903
2904 if (elf_hash_table (info)->dynamic_sections_created)
2905 {
2906 struct elf_info_failed eif;
2907 struct elf_link_hash_entry *h;
2908 bfd_size_type strsize;
2909
2910 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
2911 BFD_ASSERT (*sinterpptr != NULL || info->shared);
2912
2913 if (soname != NULL)
2914 {
2915 soname_indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2916 soname, true, true);
2917 if (soname_indx == (bfd_size_type) -1
2918 || ! elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
2919 return false;
2920 }
2921
2922 if (info->symbolic)
2923 {
2924 if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
2925 return false;
2926 info->flags |= DF_SYMBOLIC;
2927 }
2928
2929 if (rpath != NULL)
2930 {
2931 bfd_size_type indx;
2932
2933 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath,
2934 true, true);
2935 if (indx == (bfd_size_type) -1
2936 || ! elf_add_dynamic_entry (info, DT_RPATH, indx)
2937 || (info->new_dtags
2938 && ! elf_add_dynamic_entry (info, DT_RUNPATH, indx)))
2939 return false;
2940 }
2941
2942 if (filter_shlib != NULL)
2943 {
2944 bfd_size_type indx;
2945
2946 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2947 filter_shlib, true, true);
2948 if (indx == (bfd_size_type) -1
2949 || ! elf_add_dynamic_entry (info, DT_FILTER, indx))
2950 return false;
2951 }
2952
2953 if (auxiliary_filters != NULL)
2954 {
2955 const char * const *p;
2956
2957 for (p = auxiliary_filters; *p != NULL; p++)
2958 {
2959 bfd_size_type indx;
2960
2961 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
2962 *p, true, true);
2963 if (indx == (bfd_size_type) -1
2964 || ! elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
2965 return false;
2966 }
2967 }
2968
2969 /* If we are supposed to export all symbols into the dynamic symbol
2970 table (this is not the normal case), then do so. */
2971 if (export_dynamic)
2972 {
2973 struct elf_info_failed eif;
2974
2975 eif.failed = false;
2976 eif.info = info;
2977 elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol,
2978 (PTR) &eif);
2979 if (eif.failed)
2980 return false;
2981 }
2982
2983 /* Attach all the symbols to their version information. */
2984 asvinfo.output_bfd = output_bfd;
2985 asvinfo.info = info;
2986 asvinfo.verdefs = verdefs;
2987 asvinfo.export_dynamic = export_dynamic;
2988 asvinfo.failed = false;
2989
2990 elf_link_hash_traverse (elf_hash_table (info),
2991 elf_link_assign_sym_version,
2992 (PTR) &asvinfo);
2993 if (asvinfo.failed)
2994 return false;
2995
2996 /* Find all symbols which were defined in a dynamic object and make
2997 the backend pick a reasonable value for them. */
2998 eif.failed = false;
2999 eif.info = info;
3000 elf_link_hash_traverse (elf_hash_table (info),
3001 elf_adjust_dynamic_symbol,
3002 (PTR) &eif);
3003 if (eif.failed)
3004 return false;
3005
3006 /* Add some entries to the .dynamic section. We fill in some of the
3007 values later, in elf_bfd_final_link, but we must add the entries
3008 now so that we know the final size of the .dynamic section. */
3009
3010 /* If there are initialization and/or finalization functions to
3011 call then add the corresponding DT_INIT/DT_FINI entries. */
3012 h = (info->init_function
3013 ? elf_link_hash_lookup (elf_hash_table (info),
3014 info->init_function, false,
3015 false, false)
3016 : NULL);
3017 if (h != NULL
3018 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3019 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3020 {
3021 if (! elf_add_dynamic_entry (info, DT_INIT, 0))
3022 return false;
3023 }
3024 h = (info->fini_function
3025 ? elf_link_hash_lookup (elf_hash_table (info),
3026 info->fini_function, false,
3027 false, false)
3028 : NULL);
3029 if (h != NULL
3030 && (h->elf_link_hash_flags & (ELF_LINK_HASH_REF_REGULAR
3031 | ELF_LINK_HASH_DEF_REGULAR)) != 0)
3032 {
3033 if (! elf_add_dynamic_entry (info, DT_FINI, 0))
3034 return false;
3035 }
3036
3037 strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3038 if (! elf_add_dynamic_entry (info, DT_HASH, 0)
3039 || ! elf_add_dynamic_entry (info, DT_STRTAB, 0)
3040 || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0)
3041 || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize)
3042 || ! elf_add_dynamic_entry (info, DT_SYMENT,
3043 sizeof (Elf_External_Sym)))
3044 return false;
3045 }
3046
3047 /* The backend must work out the sizes of all the other dynamic
3048 sections. */
3049 if (bed->elf_backend_size_dynamic_sections
3050 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
3051 return false;
3052
3053 if (elf_hash_table (info)->dynamic_sections_created)
3054 {
3055 size_t dynsymcount;
3056 asection *s;
3057 size_t bucketcount = 0;
3058 Elf_Internal_Sym isym;
3059 size_t hash_entry_size;
3060
3061 /* Set up the version definition section. */
3062 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3063 BFD_ASSERT (s != NULL);
3064
3065 /* We may have created additional version definitions if we are
3066 just linking a regular application. */
3067 verdefs = asvinfo.verdefs;
3068
3069 if (verdefs == NULL)
3070 _bfd_strip_section_from_output (info, s);
3071 else
3072 {
3073 unsigned int cdefs;
3074 bfd_size_type size;
3075 struct bfd_elf_version_tree *t;
3076 bfd_byte *p;
3077 Elf_Internal_Verdef def;
3078 Elf_Internal_Verdaux defaux;
3079
3080 cdefs = 0;
3081 size = 0;
3082
3083 /* Make space for the base version. */
3084 size += sizeof (Elf_External_Verdef);
3085 size += sizeof (Elf_External_Verdaux);
3086 ++cdefs;
3087
3088 for (t = verdefs; t != NULL; t = t->next)
3089 {
3090 struct bfd_elf_version_deps *n;
3091
3092 size += sizeof (Elf_External_Verdef);
3093 size += sizeof (Elf_External_Verdaux);
3094 ++cdefs;
3095
3096 for (n = t->deps; n != NULL; n = n->next)
3097 size += sizeof (Elf_External_Verdaux);
3098 }
3099
3100 s->_raw_size = size;
3101 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3102 if (s->contents == NULL && s->_raw_size != 0)
3103 return false;
3104
3105 /* Fill in the version definition section. */
3106
3107 p = s->contents;
3108
3109 def.vd_version = VER_DEF_CURRENT;
3110 def.vd_flags = VER_FLG_BASE;
3111 def.vd_ndx = 1;
3112 def.vd_cnt = 1;
3113 def.vd_aux = sizeof (Elf_External_Verdef);
3114 def.vd_next = (sizeof (Elf_External_Verdef)
3115 + sizeof (Elf_External_Verdaux));
3116
3117 if (soname_indx != (bfd_size_type) -1)
3118 {
3119 def.vd_hash = bfd_elf_hash (soname);
3120 defaux.vda_name = soname_indx;
3121 }
3122 else
3123 {
3124 const char *name;
3125 bfd_size_type indx;
3126
3127 name = output_bfd->filename;
3128 def.vd_hash = bfd_elf_hash (name);
3129 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3130 name, true, false);
3131 if (indx == (bfd_size_type) -1)
3132 return false;
3133 defaux.vda_name = indx;
3134 }
3135 defaux.vda_next = 0;
3136
3137 _bfd_elf_swap_verdef_out (output_bfd, &def,
3138 (Elf_External_Verdef *)p);
3139 p += sizeof (Elf_External_Verdef);
3140 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3141 (Elf_External_Verdaux *) p);
3142 p += sizeof (Elf_External_Verdaux);
3143
3144 for (t = verdefs; t != NULL; t = t->next)
3145 {
3146 unsigned int cdeps;
3147 struct bfd_elf_version_deps *n;
3148 struct elf_link_hash_entry *h;
3149
3150 cdeps = 0;
3151 for (n = t->deps; n != NULL; n = n->next)
3152 ++cdeps;
3153
3154 /* Add a symbol representing this version. */
3155 h = NULL;
3156 if (! (_bfd_generic_link_add_one_symbol
3157 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
3158 (bfd_vma) 0, (const char *) NULL, false,
3159 get_elf_backend_data (dynobj)->collect,
3160 (struct bfd_link_hash_entry **) &h)))
3161 return false;
3162 h->elf_link_hash_flags &= ~ ELF_LINK_NON_ELF;
3163 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3164 h->type = STT_OBJECT;
3165 h->verinfo.vertree = t;
3166
3167 if (! _bfd_elf_link_record_dynamic_symbol (info, h))
3168 return false;
3169
3170 def.vd_version = VER_DEF_CURRENT;
3171 def.vd_flags = 0;
3172 if (t->globals == NULL && t->locals == NULL && ! t->used)
3173 def.vd_flags |= VER_FLG_WEAK;
3174 def.vd_ndx = t->vernum + 1;
3175 def.vd_cnt = cdeps + 1;
3176 def.vd_hash = bfd_elf_hash (t->name);
3177 def.vd_aux = sizeof (Elf_External_Verdef);
3178 if (t->next != NULL)
3179 def.vd_next = (sizeof (Elf_External_Verdef)
3180 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
3181 else
3182 def.vd_next = 0;
3183
3184 _bfd_elf_swap_verdef_out (output_bfd, &def,
3185 (Elf_External_Verdef *) p);
3186 p += sizeof (Elf_External_Verdef);
3187
3188 defaux.vda_name = h->dynstr_index;
3189 if (t->deps == NULL)
3190 defaux.vda_next = 0;
3191 else
3192 defaux.vda_next = sizeof (Elf_External_Verdaux);
3193 t->name_indx = defaux.vda_name;
3194
3195 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3196 (Elf_External_Verdaux *) p);
3197 p += sizeof (Elf_External_Verdaux);
3198
3199 for (n = t->deps; n != NULL; n = n->next)
3200 {
3201 if (n->version_needed == NULL)
3202 {
3203 /* This can happen if there was an error in the
3204 version script. */
3205 defaux.vda_name = 0;
3206 }
3207 else
3208 defaux.vda_name = n->version_needed->name_indx;
3209 if (n->next == NULL)
3210 defaux.vda_next = 0;
3211 else
3212 defaux.vda_next = sizeof (Elf_External_Verdaux);
3213
3214 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
3215 (Elf_External_Verdaux *) p);
3216 p += sizeof (Elf_External_Verdaux);
3217 }
3218 }
3219
3220 if (! elf_add_dynamic_entry (info, DT_VERDEF, 0)
3221 || ! elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
3222 return false;
3223
3224 elf_tdata (output_bfd)->cverdefs = cdefs;
3225 }
3226
3227 if (info->new_dtags && info->flags)
3228 {
3229 if (! elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
3230 return false;
3231 }
3232
3233 if (info->flags_1)
3234 {
3235 if (! info->shared)
3236 info->flags_1 &= ~ (DF_1_INITFIRST
3237 | DF_1_NODELETE
3238 | DF_1_NOOPEN);
3239 if (! elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
3240 return false;
3241 }
3242
3243 /* Work out the size of the version reference section. */
3244
3245 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3246 BFD_ASSERT (s != NULL);
3247 {
3248 struct elf_find_verdep_info sinfo;
3249
3250 sinfo.output_bfd = output_bfd;
3251 sinfo.info = info;
3252 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
3253 if (sinfo.vers == 0)
3254 sinfo.vers = 1;
3255 sinfo.failed = false;
3256
3257 elf_link_hash_traverse (elf_hash_table (info),
3258 elf_link_find_version_dependencies,
3259 (PTR) &sinfo);
3260
3261 if (elf_tdata (output_bfd)->verref == NULL)
3262 _bfd_strip_section_from_output (info, s);
3263 else
3264 {
3265 Elf_Internal_Verneed *t;
3266 unsigned int size;
3267 unsigned int crefs;
3268 bfd_byte *p;
3269
3270 /* Build the version definition section. */
3271 size = 0;
3272 crefs = 0;
3273 for (t = elf_tdata (output_bfd)->verref;
3274 t != NULL;
3275 t = t->vn_nextref)
3276 {
3277 Elf_Internal_Vernaux *a;
3278
3279 size += sizeof (Elf_External_Verneed);
3280 ++crefs;
3281 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3282 size += sizeof (Elf_External_Vernaux);
3283 }
3284
3285 s->_raw_size = size;
3286 s->contents = (bfd_byte *) bfd_alloc (output_bfd, size);
3287 if (s->contents == NULL)
3288 return false;
3289
3290 p = s->contents;
3291 for (t = elf_tdata (output_bfd)->verref;
3292 t != NULL;
3293 t = t->vn_nextref)
3294 {
3295 unsigned int caux;
3296 Elf_Internal_Vernaux *a;
3297 bfd_size_type indx;
3298
3299 caux = 0;
3300 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3301 ++caux;
3302
3303 t->vn_version = VER_NEED_CURRENT;
3304 t->vn_cnt = caux;
3305 if (elf_dt_name (t->vn_bfd) != NULL)
3306 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3307 elf_dt_name (t->vn_bfd),
3308 true, false);
3309 else
3310 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3311 t->vn_bfd->filename, true, false);
3312 if (indx == (bfd_size_type) -1)
3313 return false;
3314 t->vn_file = indx;
3315 t->vn_aux = sizeof (Elf_External_Verneed);
3316 if (t->vn_nextref == NULL)
3317 t->vn_next = 0;
3318 else
3319 t->vn_next = (sizeof (Elf_External_Verneed)
3320 + caux * sizeof (Elf_External_Vernaux));
3321
3322 _bfd_elf_swap_verneed_out (output_bfd, t,
3323 (Elf_External_Verneed *) p);
3324 p += sizeof (Elf_External_Verneed);
3325
3326 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3327 {
3328 a->vna_hash = bfd_elf_hash (a->vna_nodename);
3329 indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr,
3330 a->vna_nodename, true, false);
3331 if (indx == (bfd_size_type) -1)
3332 return false;
3333 a->vna_name = indx;
3334 if (a->vna_nextptr == NULL)
3335 a->vna_next = 0;
3336 else
3337 a->vna_next = sizeof (Elf_External_Vernaux);
3338
3339 _bfd_elf_swap_vernaux_out (output_bfd, a,
3340 (Elf_External_Vernaux *) p);
3341 p += sizeof (Elf_External_Vernaux);
3342 }
3343 }
3344
3345 if (! elf_add_dynamic_entry (info, DT_VERNEED, 0)
3346 || ! elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
3347 return false;
3348
3349 elf_tdata (output_bfd)->cverrefs = crefs;
3350 }
3351 }
3352
3353 /* Assign dynsym indicies. In a shared library we generate a
3354 section symbol for each output section, which come first.
3355 Next come all of the back-end allocated local dynamic syms,
3356 followed by the rest of the global symbols. */
3357
3358 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3359
3360 /* Work out the size of the symbol version section. */
3361 s = bfd_get_section_by_name (dynobj, ".gnu.version");
3362 BFD_ASSERT (s != NULL);
3363 if (dynsymcount == 0
3364 || (verdefs == NULL && elf_tdata (output_bfd)->verref == NULL))
3365 {
3366 _bfd_strip_section_from_output (info, s);
3367 /* The DYNSYMCOUNT might have changed if we were going to
3368 output a dynamic symbol table entry for S. */
3369 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info);
3370 }
3371 else
3372 {
3373 s->_raw_size = dynsymcount * sizeof (Elf_External_Versym);
3374 s->contents = (bfd_byte *) bfd_zalloc (output_bfd, s->_raw_size);
3375 if (s->contents == NULL)
3376 return false;
3377
3378 if (! elf_add_dynamic_entry (info, DT_VERSYM, 0))
3379 return false;
3380 }
3381
3382 /* Set the size of the .dynsym and .hash sections. We counted
3383 the number of dynamic symbols in elf_link_add_object_symbols.
3384 We will build the contents of .dynsym and .hash when we build
3385 the final symbol table, because until then we do not know the
3386 correct value to give the symbols. We built the .dynstr
3387 section as we went along in elf_link_add_object_symbols. */
3388 s = bfd_get_section_by_name (dynobj, ".dynsym");
3389 BFD_ASSERT (s != NULL);
3390 s->_raw_size = dynsymcount * sizeof (Elf_External_Sym);
3391 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3392 if (s->contents == NULL && s->_raw_size != 0)
3393 return false;
3394
3395 /* The first entry in .dynsym is a dummy symbol. */
3396 isym.st_value = 0;
3397 isym.st_size = 0;
3398 isym.st_name = 0;
3399 isym.st_info = 0;
3400 isym.st_other = 0;
3401 isym.st_shndx = 0;
3402 elf_swap_symbol_out (output_bfd, &isym,
3403 (PTR) (Elf_External_Sym *) s->contents);
3404
3405 /* Compute the size of the hashing table. As a side effect this
3406 computes the hash values for all the names we export. */
3407 bucketcount = compute_bucket_count (info);
3408
3409 s = bfd_get_section_by_name (dynobj, ".hash");
3410 BFD_ASSERT (s != NULL);
3411 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
3412 s->_raw_size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
3413 s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size);
3414 if (s->contents == NULL)
3415 return false;
3416 memset (s->contents, 0, (size_t) s->_raw_size);
3417
3418 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
3419 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
3420 s->contents + hash_entry_size);
3421
3422 elf_hash_table (info)->bucketcount = bucketcount;
3423
3424 s = bfd_get_section_by_name (dynobj, ".dynstr");
3425 BFD_ASSERT (s != NULL);
3426 s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr);
3427
3428 if (! elf_add_dynamic_entry (info, DT_NULL, 0))
3429 return false;
3430 }
3431
3432 return true;
3433 }
3434 \f
3435 /* Fix up the flags for a symbol. This handles various cases which
3436 can only be fixed after all the input files are seen. This is
3437 currently called by both adjust_dynamic_symbol and
3438 assign_sym_version, which is unnecessary but perhaps more robust in
3439 the face of future changes. */
3440
3441 static boolean
3442 elf_fix_symbol_flags (h, eif)
3443 struct elf_link_hash_entry *h;
3444 struct elf_info_failed *eif;
3445 {
3446 /* If this symbol was mentioned in a non-ELF file, try to set
3447 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
3448 permit a non-ELF file to correctly refer to a symbol defined in
3449 an ELF dynamic object. */
3450 if ((h->elf_link_hash_flags & ELF_LINK_NON_ELF) != 0)
3451 {
3452 while (h->root.type == bfd_link_hash_indirect)
3453 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3454
3455 if (h->root.type != bfd_link_hash_defined
3456 && h->root.type != bfd_link_hash_defweak)
3457 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3458 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3459 else
3460 {
3461 if (h->root.u.def.section->owner != NULL
3462 && (bfd_get_flavour (h->root.u.def.section->owner)
3463 == bfd_target_elf_flavour))
3464 h->elf_link_hash_flags |= (ELF_LINK_HASH_REF_REGULAR
3465 | ELF_LINK_HASH_REF_REGULAR_NONWEAK);
3466 else
3467 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3468 }
3469
3470 if (h->dynindx == -1
3471 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
3472 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0))
3473 {
3474 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3475 {
3476 eif->failed = true;
3477 return false;
3478 }
3479 }
3480 }
3481 else
3482 {
3483 /* Unfortunately, ELF_LINK_NON_ELF is only correct if the symbol
3484 was first seen in a non-ELF file. Fortunately, if the symbol
3485 was first seen in an ELF file, we're probably OK unless the
3486 symbol was defined in a non-ELF file. Catch that case here.
3487 FIXME: We're still in trouble if the symbol was first seen in
3488 a dynamic object, and then later in a non-ELF regular object. */
3489 if ((h->root.type == bfd_link_hash_defined
3490 || h->root.type == bfd_link_hash_defweak)
3491 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3492 && (h->root.u.def.section->owner != NULL
3493 ? (bfd_get_flavour (h->root.u.def.section->owner)
3494 != bfd_target_elf_flavour)
3495 : (bfd_is_abs_section (h->root.u.def.section)
3496 && (h->elf_link_hash_flags
3497 & ELF_LINK_HASH_DEF_DYNAMIC) == 0)))
3498 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3499 }
3500
3501 /* If this is a final link, and the symbol was defined as a common
3502 symbol in a regular object file, and there was no definition in
3503 any dynamic object, then the linker will have allocated space for
3504 the symbol in a common section but the ELF_LINK_HASH_DEF_REGULAR
3505 flag will not have been set. */
3506 if (h->root.type == bfd_link_hash_defined
3507 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
3508 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
3509 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3510 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3511 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
3512
3513 /* If -Bsymbolic was used (which means to bind references to global
3514 symbols to the definition within the shared object), and this
3515 symbol was defined in a regular object, then it actually doesn't
3516 need a PLT entry. Likewise, if the symbol has any kind of
3517 visibility (internal, hidden, or protected), it doesn't need a
3518 PLT. */
3519 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0
3520 && eif->info->shared
3521 && (eif->info->symbolic || ELF_ST_VISIBILITY (h->other))
3522 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3523 {
3524 h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT;
3525 h->plt.offset = (bfd_vma) -1;
3526 }
3527
3528 /* If this is a weak defined symbol in a dynamic object, and we know
3529 the real definition in the dynamic object, copy interesting flags
3530 over to the real definition. */
3531 if (h->weakdef != NULL)
3532 {
3533 struct elf_link_hash_entry *weakdef;
3534
3535 BFD_ASSERT (h->root.type == bfd_link_hash_defined
3536 || h->root.type == bfd_link_hash_defweak);
3537 weakdef = h->weakdef;
3538 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
3539 || weakdef->root.type == bfd_link_hash_defweak);
3540 BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC);
3541
3542 /* If the real definition is defined by a regular object file,
3543 don't do anything special. See the longer description in
3544 elf_adjust_dynamic_symbol, below. */
3545 if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0)
3546 h->weakdef = NULL;
3547 else
3548 weakdef->elf_link_hash_flags |=
3549 (h->elf_link_hash_flags
3550 & (ELF_LINK_HASH_REF_REGULAR
3551 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
3552 | ELF_LINK_NON_GOT_REF));
3553 }
3554
3555 return true;
3556 }
3557
3558 /* Make the backend pick a good value for a dynamic symbol. This is
3559 called via elf_link_hash_traverse, and also calls itself
3560 recursively. */
3561
3562 static boolean
3563 elf_adjust_dynamic_symbol (h, data)
3564 struct elf_link_hash_entry *h;
3565 PTR data;
3566 {
3567 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3568 bfd *dynobj;
3569 struct elf_backend_data *bed;
3570
3571 /* Ignore indirect symbols. These are added by the versioning code. */
3572 if (h->root.type == bfd_link_hash_indirect)
3573 return true;
3574
3575 /* Fix the symbol flags. */
3576 if (! elf_fix_symbol_flags (h, eif))
3577 return false;
3578
3579 /* If this symbol does not require a PLT entry, and it is not
3580 defined by a dynamic object, or is not referenced by a regular
3581 object, ignore it. We do have to handle a weak defined symbol,
3582 even if no regular object refers to it, if we decided to add it
3583 to the dynamic symbol table. FIXME: Do we normally need to worry
3584 about symbols which are defined by one dynamic object and
3585 referenced by another one? */
3586 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0
3587 && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3588 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3589 || ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0
3590 && (h->weakdef == NULL || h->weakdef->dynindx == -1))))
3591 {
3592 h->plt.offset = (bfd_vma) -1;
3593 return true;
3594 }
3595
3596 /* If we've already adjusted this symbol, don't do it again. This
3597 can happen via a recursive call. */
3598 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
3599 return true;
3600
3601 /* Don't look at this symbol again. Note that we must set this
3602 after checking the above conditions, because we may look at a
3603 symbol once, decide not to do anything, and then get called
3604 recursively later after REF_REGULAR is set below. */
3605 h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED;
3606
3607 /* If this is a weak definition, and we know a real definition, and
3608 the real symbol is not itself defined by a regular object file,
3609 then get a good value for the real definition. We handle the
3610 real symbol first, for the convenience of the backend routine.
3611
3612 Note that there is a confusing case here. If the real definition
3613 is defined by a regular object file, we don't get the real symbol
3614 from the dynamic object, but we do get the weak symbol. If the
3615 processor backend uses a COPY reloc, then if some routine in the
3616 dynamic object changes the real symbol, we will not see that
3617 change in the corresponding weak symbol. This is the way other
3618 ELF linkers work as well, and seems to be a result of the shared
3619 library model.
3620
3621 I will clarify this issue. Most SVR4 shared libraries define the
3622 variable _timezone and define timezone as a weak synonym. The
3623 tzset call changes _timezone. If you write
3624 extern int timezone;
3625 int _timezone = 5;
3626 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3627 you might expect that, since timezone is a synonym for _timezone,
3628 the same number will print both times. However, if the processor
3629 backend uses a COPY reloc, then actually timezone will be copied
3630 into your process image, and, since you define _timezone
3631 yourself, _timezone will not. Thus timezone and _timezone will
3632 wind up at different memory locations. The tzset call will set
3633 _timezone, leaving timezone unchanged. */
3634
3635 if (h->weakdef != NULL)
3636 {
3637 /* If we get to this point, we know there is an implicit
3638 reference by a regular object file via the weak symbol H.
3639 FIXME: Is this really true? What if the traversal finds
3640 H->WEAKDEF before it finds H? */
3641 h->weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR;
3642
3643 if (! elf_adjust_dynamic_symbol (h->weakdef, (PTR) eif))
3644 return false;
3645 }
3646
3647 /* If a symbol has no type and no size and does not require a PLT
3648 entry, then we are probably about to do the wrong thing here: we
3649 are probably going to create a COPY reloc for an empty object.
3650 This case can arise when a shared object is built with assembly
3651 code, and the assembly code fails to set the symbol type. */
3652 if (h->size == 0
3653 && h->type == STT_NOTYPE
3654 && (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0)
3655 (*_bfd_error_handler)
3656 (_("warning: type and size of dynamic symbol `%s' are not defined"),
3657 h->root.root.string);
3658
3659 dynobj = elf_hash_table (eif->info)->dynobj;
3660 bed = get_elf_backend_data (dynobj);
3661 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3662 {
3663 eif->failed = true;
3664 return false;
3665 }
3666
3667 return true;
3668 }
3669 \f
3670 /* This routine is used to export all defined symbols into the dynamic
3671 symbol table. It is called via elf_link_hash_traverse. */
3672
3673 static boolean
3674 elf_export_symbol (h, data)
3675 struct elf_link_hash_entry *h;
3676 PTR data;
3677 {
3678 struct elf_info_failed *eif = (struct elf_info_failed *) data;
3679
3680 /* Ignore indirect symbols. These are added by the versioning code. */
3681 if (h->root.type == bfd_link_hash_indirect)
3682 return true;
3683
3684 if (h->dynindx == -1
3685 && (h->elf_link_hash_flags
3686 & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0)
3687 {
3688 if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h))
3689 {
3690 eif->failed = true;
3691 return false;
3692 }
3693 }
3694
3695 return true;
3696 }
3697 \f
3698 /* Look through the symbols which are defined in other shared
3699 libraries and referenced here. Update the list of version
3700 dependencies. This will be put into the .gnu.version_r section.
3701 This function is called via elf_link_hash_traverse. */
3702
3703 static boolean
3704 elf_link_find_version_dependencies (h, data)
3705 struct elf_link_hash_entry *h;
3706 PTR data;
3707 {
3708 struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
3709 Elf_Internal_Verneed *t;
3710 Elf_Internal_Vernaux *a;
3711
3712 /* We only care about symbols defined in shared objects with version
3713 information. */
3714 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
3715 || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
3716 || h->dynindx == -1
3717 || h->verinfo.verdef == NULL)
3718 return true;
3719
3720 /* See if we already know about this version. */
3721 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
3722 {
3723 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
3724 continue;
3725
3726 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3727 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
3728 return true;
3729
3730 break;
3731 }
3732
3733 /* This is a new version. Add it to tree we are building. */
3734
3735 if (t == NULL)
3736 {
3737 t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->output_bfd, sizeof *t);
3738 if (t == NULL)
3739 {
3740 rinfo->failed = true;
3741 return false;
3742 }
3743
3744 t->vn_bfd = h->verinfo.verdef->vd_bfd;
3745 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
3746 elf_tdata (rinfo->output_bfd)->verref = t;
3747 }
3748
3749 a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->output_bfd, sizeof *a);
3750
3751 /* Note that we are copying a string pointer here, and testing it
3752 above. If bfd_elf_string_from_elf_section is ever changed to
3753 discard the string data when low in memory, this will have to be
3754 fixed. */
3755 a->vna_nodename = h->verinfo.verdef->vd_nodename;
3756
3757 a->vna_flags = h->verinfo.verdef->vd_flags;
3758 a->vna_nextptr = t->vn_auxptr;
3759
3760 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
3761 ++rinfo->vers;
3762
3763 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
3764
3765 t->vn_auxptr = a;
3766
3767 return true;
3768 }
3769
3770 /* Figure out appropriate versions for all the symbols. We may not
3771 have the version number script until we have read all of the input
3772 files, so until that point we don't know which symbols should be
3773 local. This function is called via elf_link_hash_traverse. */
3774
3775 static boolean
3776 elf_link_assign_sym_version (h, data)
3777 struct elf_link_hash_entry *h;
3778 PTR data;
3779 {
3780 struct elf_assign_sym_version_info *sinfo =
3781 (struct elf_assign_sym_version_info *) data;
3782 struct bfd_link_info *info = sinfo->info;
3783 struct elf_backend_data *bed;
3784 struct elf_info_failed eif;
3785 char *p;
3786
3787 /* Fix the symbol flags. */
3788 eif.failed = false;
3789 eif.info = info;
3790 if (! elf_fix_symbol_flags (h, &eif))
3791 {
3792 if (eif.failed)
3793 sinfo->failed = true;
3794 return false;
3795 }
3796
3797 /* We only need version numbers for symbols defined in regular
3798 objects. */
3799 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3800 return true;
3801
3802 bed = get_elf_backend_data (sinfo->output_bfd);
3803 p = strchr (h->root.root.string, ELF_VER_CHR);
3804 if (p != NULL && h->verinfo.vertree == NULL)
3805 {
3806 struct bfd_elf_version_tree *t;
3807 boolean hidden;
3808
3809 hidden = true;
3810
3811 /* There are two consecutive ELF_VER_CHR characters if this is
3812 not a hidden symbol. */
3813 ++p;
3814 if (*p == ELF_VER_CHR)
3815 {
3816 hidden = false;
3817 ++p;
3818 }
3819
3820 /* If there is no version string, we can just return out. */
3821 if (*p == '\0')
3822 {
3823 if (hidden)
3824 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3825 return true;
3826 }
3827
3828 /* Look for the version. If we find it, it is no longer weak. */
3829 for (t = sinfo->verdefs; t != NULL; t = t->next)
3830 {
3831 if (strcmp (t->name, p) == 0)
3832 {
3833 int len;
3834 char *alc;
3835 struct bfd_elf_version_expr *d;
3836
3837 len = p - h->root.root.string;
3838 alc = bfd_alloc (sinfo->output_bfd, len);
3839 if (alc == NULL)
3840 return false;
3841 strncpy (alc, h->root.root.string, len - 1);
3842 alc[len - 1] = '\0';
3843 if (alc[len - 2] == ELF_VER_CHR)
3844 alc[len - 2] = '\0';
3845
3846 h->verinfo.vertree = t;
3847 t->used = true;
3848 d = NULL;
3849
3850 if (t->globals != NULL)
3851 {
3852 for (d = t->globals; d != NULL; d = d->next)
3853 if ((*d->match) (d, alc))
3854 break;
3855 }
3856
3857 /* See if there is anything to force this symbol to
3858 local scope. */
3859 if (d == NULL && t->locals != NULL)
3860 {
3861 for (d = t->locals; d != NULL; d = d->next)
3862 {
3863 if ((*d->match) (d, alc))
3864 {
3865 if (h->dynindx != -1
3866 && info->shared
3867 && ! sinfo->export_dynamic)
3868 {
3869 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3870 (*bed->elf_backend_hide_symbol) (info, h);
3871 /* FIXME: The name of the symbol has
3872 already been recorded in the dynamic
3873 string table section. */
3874 }
3875
3876 break;
3877 }
3878 }
3879 }
3880
3881 bfd_release (sinfo->output_bfd, alc);
3882 break;
3883 }
3884 }
3885
3886 /* If we are building an application, we need to create a
3887 version node for this version. */
3888 if (t == NULL && ! info->shared)
3889 {
3890 struct bfd_elf_version_tree **pp;
3891 int version_index;
3892
3893 /* If we aren't going to export this symbol, we don't need
3894 to worry about it. */
3895 if (h->dynindx == -1)
3896 return true;
3897
3898 t = ((struct bfd_elf_version_tree *)
3899 bfd_alloc (sinfo->output_bfd, sizeof *t));
3900 if (t == NULL)
3901 {
3902 sinfo->failed = true;
3903 return false;
3904 }
3905
3906 t->next = NULL;
3907 t->name = p;
3908 t->globals = NULL;
3909 t->locals = NULL;
3910 t->deps = NULL;
3911 t->name_indx = (unsigned int) -1;
3912 t->used = true;
3913
3914 version_index = 1;
3915 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
3916 ++version_index;
3917 t->vernum = version_index;
3918
3919 *pp = t;
3920
3921 h->verinfo.vertree = t;
3922 }
3923 else if (t == NULL)
3924 {
3925 /* We could not find the version for a symbol when
3926 generating a shared archive. Return an error. */
3927 (*_bfd_error_handler)
3928 (_("%s: undefined versioned symbol name %s"),
3929 bfd_get_filename (sinfo->output_bfd), h->root.root.string);
3930 bfd_set_error (bfd_error_bad_value);
3931 sinfo->failed = true;
3932 return false;
3933 }
3934
3935 if (hidden)
3936 h->elf_link_hash_flags |= ELF_LINK_HIDDEN;
3937 }
3938
3939 /* If we don't have a version for this symbol, see if we can find
3940 something. */
3941 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
3942 {
3943 struct bfd_elf_version_tree *t;
3944 struct bfd_elf_version_tree *deflt;
3945 struct bfd_elf_version_expr *d;
3946
3947 /* See if can find what version this symbol is in. If the
3948 symbol is supposed to be local, then don't actually register
3949 it. */
3950 deflt = NULL;
3951 for (t = sinfo->verdefs; t != NULL; t = t->next)
3952 {
3953 if (t->globals != NULL)
3954 {
3955 for (d = t->globals; d != NULL; d = d->next)
3956 {
3957 if ((*d->match) (d, h->root.root.string))
3958 {
3959 h->verinfo.vertree = t;
3960 break;
3961 }
3962 }
3963
3964 if (d != NULL)
3965 break;
3966 }
3967
3968 if (t->locals != NULL)
3969 {
3970 for (d = t->locals; d != NULL; d = d->next)
3971 {
3972 if (d->pattern[0] == '*' && d->pattern[1] == '\0')
3973 deflt = t;
3974 else if ((*d->match) (d, h->root.root.string))
3975 {
3976 h->verinfo.vertree = t;
3977 if (h->dynindx != -1
3978 && info->shared
3979 && ! sinfo->export_dynamic)
3980 {
3981 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
3982 (*bed->elf_backend_hide_symbol) (info, h);
3983 /* FIXME: The name of the symbol has already
3984 been recorded in the dynamic string table
3985 section. */
3986 }
3987 break;
3988 }
3989 }
3990
3991 if (d != NULL)
3992 break;
3993 }
3994 }
3995
3996 if (deflt != NULL && h->verinfo.vertree == NULL)
3997 {
3998 h->verinfo.vertree = deflt;
3999 if (h->dynindx != -1
4000 && info->shared
4001 && ! sinfo->export_dynamic)
4002 {
4003 h->elf_link_hash_flags |= ELF_LINK_FORCED_LOCAL;
4004 (*bed->elf_backend_hide_symbol) (info, h);
4005 /* FIXME: The name of the symbol has already been
4006 recorded in the dynamic string table section. */
4007 }
4008 }
4009 }
4010
4011 return true;
4012 }
4013 \f
4014 /* Final phase of ELF linker. */
4015
4016 /* A structure we use to avoid passing large numbers of arguments. */
4017
4018 struct elf_final_link_info
4019 {
4020 /* General link information. */
4021 struct bfd_link_info *info;
4022 /* Output BFD. */
4023 bfd *output_bfd;
4024 /* Symbol string table. */
4025 struct bfd_strtab_hash *symstrtab;
4026 /* .dynsym section. */
4027 asection *dynsym_sec;
4028 /* .hash section. */
4029 asection *hash_sec;
4030 /* symbol version section (.gnu.version). */
4031 asection *symver_sec;
4032 /* Buffer large enough to hold contents of any section. */
4033 bfd_byte *contents;
4034 /* Buffer large enough to hold external relocs of any section. */
4035 PTR external_relocs;
4036 /* Buffer large enough to hold internal relocs of any section. */
4037 Elf_Internal_Rela *internal_relocs;
4038 /* Buffer large enough to hold external local symbols of any input
4039 BFD. */
4040 Elf_External_Sym *external_syms;
4041 /* Buffer large enough to hold internal local symbols of any input
4042 BFD. */
4043 Elf_Internal_Sym *internal_syms;
4044 /* Array large enough to hold a symbol index for each local symbol
4045 of any input BFD. */
4046 long *indices;
4047 /* Array large enough to hold a section pointer for each local
4048 symbol of any input BFD. */
4049 asection **sections;
4050 /* Buffer to hold swapped out symbols. */
4051 Elf_External_Sym *symbuf;
4052 /* Number of swapped out symbols in buffer. */
4053 size_t symbuf_count;
4054 /* Number of symbols which fit in symbuf. */
4055 size_t symbuf_size;
4056 };
4057
4058 static boolean elf_link_output_sym
4059 PARAMS ((struct elf_final_link_info *, const char *,
4060 Elf_Internal_Sym *, asection *));
4061 static boolean elf_link_flush_output_syms
4062 PARAMS ((struct elf_final_link_info *));
4063 static boolean elf_link_output_extsym
4064 PARAMS ((struct elf_link_hash_entry *, PTR));
4065 static boolean elf_link_input_bfd
4066 PARAMS ((struct elf_final_link_info *, bfd *));
4067 static boolean elf_reloc_link_order
4068 PARAMS ((bfd *, struct bfd_link_info *, asection *,
4069 struct bfd_link_order *));
4070
4071 /* This struct is used to pass information to elf_link_output_extsym. */
4072
4073 struct elf_outext_info
4074 {
4075 boolean failed;
4076 boolean localsyms;
4077 struct elf_final_link_info *finfo;
4078 };
4079
4080 /* Compute the size of, and allocate space for, REL_HDR which is the
4081 section header for a section containing relocations for O. */
4082
4083 static boolean
4084 elf_link_size_reloc_section (abfd, rel_hdr, o)
4085 bfd *abfd;
4086 Elf_Internal_Shdr *rel_hdr;
4087 asection *o;
4088 {
4089 register struct elf_link_hash_entry **p, **pend;
4090 unsigned reloc_count;
4091
4092 /* Figure out how many relocations there will be. */
4093 if (rel_hdr == &elf_section_data (o)->rel_hdr)
4094 reloc_count = elf_section_data (o)->rel_count;
4095 else
4096 reloc_count = elf_section_data (o)->rel_count2;
4097
4098 /* That allows us to calculate the size of the section. */
4099 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
4100
4101 /* The contents field must last into write_object_contents, so we
4102 allocate it with bfd_alloc rather than malloc. Also since we
4103 cannot be sure that the contents will actually be filled in,
4104 we zero the allocated space. */
4105 rel_hdr->contents = (PTR) bfd_zalloc (abfd, rel_hdr->sh_size);
4106 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
4107 return false;
4108
4109 /* We only allocate one set of hash entries, so we only do it the
4110 first time we are called. */
4111 if (elf_section_data (o)->rel_hashes == NULL)
4112 {
4113 p = ((struct elf_link_hash_entry **)
4114 bfd_malloc (o->reloc_count
4115 * sizeof (struct elf_link_hash_entry *)));
4116 if (p == NULL && o->reloc_count != 0)
4117 return false;
4118
4119 elf_section_data (o)->rel_hashes = p;
4120 pend = p + o->reloc_count;
4121 for (; p < pend; p++)
4122 *p = NULL;
4123 }
4124
4125 return true;
4126 }
4127
4128 /* When performing a relocateable link, the input relocations are
4129 preserved. But, if they reference global symbols, the indices
4130 referenced must be updated. Update all the relocations in
4131 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
4132
4133 static void
4134 elf_link_adjust_relocs (abfd, rel_hdr, count, rel_hash)
4135 bfd *abfd;
4136 Elf_Internal_Shdr *rel_hdr;
4137 unsigned int count;
4138 struct elf_link_hash_entry **rel_hash;
4139 {
4140 unsigned int i;
4141 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4142
4143 for (i = 0; i < count; i++, rel_hash++)
4144 {
4145 if (*rel_hash == NULL)
4146 continue;
4147
4148 BFD_ASSERT ((*rel_hash)->indx >= 0);
4149
4150 if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
4151 {
4152 Elf_External_Rel *erel;
4153 Elf_Internal_Rel irel;
4154
4155 erel = (Elf_External_Rel *) rel_hdr->contents + i;
4156 if (bed->s->swap_reloc_in)
4157 (*bed->s->swap_reloc_in) (abfd, (bfd_byte *) erel, &irel);
4158 else
4159 elf_swap_reloc_in (abfd, erel, &irel);
4160 irel.r_info = ELF_R_INFO ((*rel_hash)->indx,
4161 ELF_R_TYPE (irel.r_info));
4162 if (bed->s->swap_reloc_out)
4163 (*bed->s->swap_reloc_out) (abfd, &irel, (bfd_byte *) erel);
4164 else
4165 elf_swap_reloc_out (abfd, &irel, erel);
4166 }
4167 else
4168 {
4169 Elf_External_Rela *erela;
4170 Elf_Internal_Rela irela;
4171
4172 BFD_ASSERT (rel_hdr->sh_entsize
4173 == sizeof (Elf_External_Rela));
4174
4175 erela = (Elf_External_Rela *) rel_hdr->contents + i;
4176 if (bed->s->swap_reloca_in)
4177 (*bed->s->swap_reloca_in) (abfd, (bfd_byte *) erela, &irela);
4178 else
4179 elf_swap_reloca_in (abfd, erela, &irela);
4180 irela.r_info = ELF_R_INFO ((*rel_hash)->indx,
4181 ELF_R_TYPE (irela.r_info));
4182 if (bed->s->swap_reloca_out)
4183 (*bed->s->swap_reloca_out) (abfd, &irela, (bfd_byte *) erela);
4184 else
4185 elf_swap_reloca_out (abfd, &irela, erela);
4186 }
4187 }
4188 }
4189
4190 /* Do the final step of an ELF link. */
4191
4192 boolean
4193 elf_bfd_final_link (abfd, info)
4194 bfd *abfd;
4195 struct bfd_link_info *info;
4196 {
4197 boolean dynamic;
4198 bfd *dynobj;
4199 struct elf_final_link_info finfo;
4200 register asection *o;
4201 register struct bfd_link_order *p;
4202 register bfd *sub;
4203 size_t max_contents_size;
4204 size_t max_external_reloc_size;
4205 size_t max_internal_reloc_count;
4206 size_t max_sym_count;
4207 file_ptr off;
4208 Elf_Internal_Sym elfsym;
4209 unsigned int i;
4210 Elf_Internal_Shdr *symtab_hdr;
4211 Elf_Internal_Shdr *symstrtab_hdr;
4212 struct elf_backend_data *bed = get_elf_backend_data (abfd);
4213 struct elf_outext_info eoinfo;
4214
4215 if (info->shared)
4216 abfd->flags |= DYNAMIC;
4217
4218 dynamic = elf_hash_table (info)->dynamic_sections_created;
4219 dynobj = elf_hash_table (info)->dynobj;
4220
4221 finfo.info = info;
4222 finfo.output_bfd = abfd;
4223 finfo.symstrtab = elf_stringtab_init ();
4224 if (finfo.symstrtab == NULL)
4225 return false;
4226
4227 if (! dynamic)
4228 {
4229 finfo.dynsym_sec = NULL;
4230 finfo.hash_sec = NULL;
4231 finfo.symver_sec = NULL;
4232 }
4233 else
4234 {
4235 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
4236 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
4237 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
4238 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
4239 /* Note that it is OK if symver_sec is NULL. */
4240 }
4241
4242 finfo.contents = NULL;
4243 finfo.external_relocs = NULL;
4244 finfo.internal_relocs = NULL;
4245 finfo.external_syms = NULL;
4246 finfo.internal_syms = NULL;
4247 finfo.indices = NULL;
4248 finfo.sections = NULL;
4249 finfo.symbuf = NULL;
4250 finfo.symbuf_count = 0;
4251
4252 /* Count up the number of relocations we will output for each output
4253 section, so that we know the sizes of the reloc sections. We
4254 also figure out some maximum sizes. */
4255 max_contents_size = 0;
4256 max_external_reloc_size = 0;
4257 max_internal_reloc_count = 0;
4258 max_sym_count = 0;
4259 for (o = abfd->sections; o != (asection *) NULL; o = o->next)
4260 {
4261 o->reloc_count = 0;
4262
4263 for (p = o->link_order_head; p != NULL; p = p->next)
4264 {
4265 if (p->type == bfd_section_reloc_link_order
4266 || p->type == bfd_symbol_reloc_link_order)
4267 ++o->reloc_count;
4268 else if (p->type == bfd_indirect_link_order)
4269 {
4270 asection *sec;
4271
4272 sec = p->u.indirect.section;
4273
4274 /* Mark all sections which are to be included in the
4275 link. This will normally be every section. We need
4276 to do this so that we can identify any sections which
4277 the linker has decided to not include. */
4278 sec->linker_mark = true;
4279
4280 if (info->relocateable || info->emitrelocations)
4281 o->reloc_count += sec->reloc_count;
4282
4283 if (sec->_raw_size > max_contents_size)
4284 max_contents_size = sec->_raw_size;
4285 if (sec->_cooked_size > max_contents_size)
4286 max_contents_size = sec->_cooked_size;
4287
4288 /* We are interested in just local symbols, not all
4289 symbols. */
4290 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
4291 && (sec->owner->flags & DYNAMIC) == 0)
4292 {
4293 size_t sym_count;
4294
4295 if (elf_bad_symtab (sec->owner))
4296 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
4297 / sizeof (Elf_External_Sym));
4298 else
4299 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
4300
4301 if (sym_count > max_sym_count)
4302 max_sym_count = sym_count;
4303
4304 if ((sec->flags & SEC_RELOC) != 0)
4305 {
4306 size_t ext_size;
4307
4308 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
4309 if (ext_size > max_external_reloc_size)
4310 max_external_reloc_size = ext_size;
4311 if (sec->reloc_count > max_internal_reloc_count)
4312 max_internal_reloc_count = sec->reloc_count;
4313 }
4314 }
4315 }
4316 }
4317
4318 if (o->reloc_count > 0)
4319 o->flags |= SEC_RELOC;
4320 else
4321 {
4322 /* Explicitly clear the SEC_RELOC flag. The linker tends to
4323 set it (this is probably a bug) and if it is set
4324 assign_section_numbers will create a reloc section. */
4325 o->flags &=~ SEC_RELOC;
4326 }
4327
4328 /* If the SEC_ALLOC flag is not set, force the section VMA to
4329 zero. This is done in elf_fake_sections as well, but forcing
4330 the VMA to 0 here will ensure that relocs against these
4331 sections are handled correctly. */
4332 if ((o->flags & SEC_ALLOC) == 0
4333 && ! o->user_set_vma)
4334 o->vma = 0;
4335 }
4336
4337 /* Figure out the file positions for everything but the symbol table
4338 and the relocs. We set symcount to force assign_section_numbers
4339 to create a symbol table. */
4340 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
4341 BFD_ASSERT (! abfd->output_has_begun);
4342 if (! _bfd_elf_compute_section_file_positions (abfd, info))
4343 goto error_return;
4344
4345 /* Figure out how many relocations we will have in each section.
4346 Just using RELOC_COUNT isn't good enough since that doesn't
4347 maintain a separate value for REL vs. RELA relocations. */
4348 if (info->relocateable || info->emitrelocations)
4349 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4350 for (o = sub->sections; o != NULL; o = o->next)
4351 {
4352 asection *output_section;
4353
4354 if (! o->linker_mark)
4355 {
4356 /* This section was omitted from the link. */
4357 continue;
4358 }
4359
4360 output_section = o->output_section;
4361
4362 if (output_section != NULL
4363 && (o->flags & SEC_RELOC) != 0)
4364 {
4365 struct bfd_elf_section_data *esdi
4366 = elf_section_data (o);
4367 struct bfd_elf_section_data *esdo
4368 = elf_section_data (output_section);
4369 unsigned int *rel_count;
4370 unsigned int *rel_count2;
4371
4372 /* We must be careful to add the relocation froms the
4373 input section to the right output count. */
4374 if (esdi->rel_hdr.sh_entsize == esdo->rel_hdr.sh_entsize)
4375 {
4376 rel_count = &esdo->rel_count;
4377 rel_count2 = &esdo->rel_count2;
4378 }
4379 else
4380 {
4381 rel_count = &esdo->rel_count2;
4382 rel_count2 = &esdo->rel_count;
4383 }
4384
4385 *rel_count += (esdi->rel_hdr.sh_size
4386 / esdi->rel_hdr.sh_entsize);
4387 if (esdi->rel_hdr2)
4388 *rel_count2 += (esdi->rel_hdr2->sh_size
4389 / esdi->rel_hdr2->sh_entsize);
4390 }
4391 }
4392
4393 /* That created the reloc sections. Set their sizes, and assign
4394 them file positions, and allocate some buffers. */
4395 for (o = abfd->sections; o != NULL; o = o->next)
4396 {
4397 if ((o->flags & SEC_RELOC) != 0)
4398 {
4399 if (!elf_link_size_reloc_section (abfd,
4400 &elf_section_data (o)->rel_hdr,
4401 o))
4402 goto error_return;
4403
4404 if (elf_section_data (o)->rel_hdr2
4405 && !elf_link_size_reloc_section (abfd,
4406 elf_section_data (o)->rel_hdr2,
4407 o))
4408 goto error_return;
4409 }
4410
4411 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
4412 to count upwards while actually outputting the relocations. */
4413 elf_section_data (o)->rel_count = 0;
4414 elf_section_data (o)->rel_count2 = 0;
4415 }
4416
4417 _bfd_elf_assign_file_positions_for_relocs (abfd);
4418
4419 /* We have now assigned file positions for all the sections except
4420 .symtab and .strtab. We start the .symtab section at the current
4421 file position, and write directly to it. We build the .strtab
4422 section in memory. */
4423 bfd_get_symcount (abfd) = 0;
4424 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
4425 /* sh_name is set in prep_headers. */
4426 symtab_hdr->sh_type = SHT_SYMTAB;
4427 symtab_hdr->sh_flags = 0;
4428 symtab_hdr->sh_addr = 0;
4429 symtab_hdr->sh_size = 0;
4430 symtab_hdr->sh_entsize = sizeof (Elf_External_Sym);
4431 /* sh_link is set in assign_section_numbers. */
4432 /* sh_info is set below. */
4433 /* sh_offset is set just below. */
4434 symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */
4435
4436 off = elf_tdata (abfd)->next_file_pos;
4437 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
4438
4439 /* Note that at this point elf_tdata (abfd)->next_file_pos is
4440 incorrect. We do not yet know the size of the .symtab section.
4441 We correct next_file_pos below, after we do know the size. */
4442
4443 /* Allocate a buffer to hold swapped out symbols. This is to avoid
4444 continuously seeking to the right position in the file. */
4445 if (! info->keep_memory || max_sym_count < 20)
4446 finfo.symbuf_size = 20;
4447 else
4448 finfo.symbuf_size = max_sym_count;
4449 finfo.symbuf = ((Elf_External_Sym *)
4450 bfd_malloc (finfo.symbuf_size * sizeof (Elf_External_Sym)));
4451 if (finfo.symbuf == NULL)
4452 goto error_return;
4453
4454 /* Start writing out the symbol table. The first symbol is always a
4455 dummy symbol. */
4456 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4457 {
4458 elfsym.st_value = 0;
4459 elfsym.st_size = 0;
4460 elfsym.st_info = 0;
4461 elfsym.st_other = 0;
4462 elfsym.st_shndx = SHN_UNDEF;
4463 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4464 &elfsym, bfd_und_section_ptr))
4465 goto error_return;
4466 }
4467
4468 #if 0
4469 /* Some standard ELF linkers do this, but we don't because it causes
4470 bootstrap comparison failures. */
4471 /* Output a file symbol for the output file as the second symbol.
4472 We output this even if we are discarding local symbols, although
4473 I'm not sure if this is correct. */
4474 elfsym.st_value = 0;
4475 elfsym.st_size = 0;
4476 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
4477 elfsym.st_other = 0;
4478 elfsym.st_shndx = SHN_ABS;
4479 if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd),
4480 &elfsym, bfd_abs_section_ptr))
4481 goto error_return;
4482 #endif
4483
4484 /* Output a symbol for each section. We output these even if we are
4485 discarding local symbols, since they are used for relocs. These
4486 symbols have no names. We store the index of each one in the
4487 index field of the section, so that we can find it again when
4488 outputting relocs. */
4489 if (info->strip != strip_all || info->relocateable || info->emitrelocations)
4490 {
4491 elfsym.st_size = 0;
4492 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4493 elfsym.st_other = 0;
4494 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4495 {
4496 o = section_from_elf_index (abfd, i);
4497 if (o != NULL)
4498 o->target_index = bfd_get_symcount (abfd);
4499 elfsym.st_shndx = i;
4500 if (info->relocateable || o == NULL)
4501 elfsym.st_value = 0;
4502 else
4503 elfsym.st_value = o->vma;
4504 if (! elf_link_output_sym (&finfo, (const char *) NULL,
4505 &elfsym, o))
4506 goto error_return;
4507 }
4508 }
4509
4510 /* Allocate some memory to hold information read in from the input
4511 files. */
4512 finfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
4513 finfo.external_relocs = (PTR) bfd_malloc (max_external_reloc_size);
4514 finfo.internal_relocs = ((Elf_Internal_Rela *)
4515 bfd_malloc (max_internal_reloc_count
4516 * sizeof (Elf_Internal_Rela)
4517 * bed->s->int_rels_per_ext_rel));
4518 finfo.external_syms = ((Elf_External_Sym *)
4519 bfd_malloc (max_sym_count
4520 * sizeof (Elf_External_Sym)));
4521 finfo.internal_syms = ((Elf_Internal_Sym *)
4522 bfd_malloc (max_sym_count
4523 * sizeof (Elf_Internal_Sym)));
4524 finfo.indices = (long *) bfd_malloc (max_sym_count * sizeof (long));
4525 finfo.sections = ((asection **)
4526 bfd_malloc (max_sym_count * sizeof (asection *)));
4527 if ((finfo.contents == NULL && max_contents_size != 0)
4528 || (finfo.external_relocs == NULL && max_external_reloc_size != 0)
4529 || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0)
4530 || (finfo.external_syms == NULL && max_sym_count != 0)
4531 || (finfo.internal_syms == NULL && max_sym_count != 0)
4532 || (finfo.indices == NULL && max_sym_count != 0)
4533 || (finfo.sections == NULL && max_sym_count != 0))
4534 goto error_return;
4535
4536 /* Since ELF permits relocations to be against local symbols, we
4537 must have the local symbols available when we do the relocations.
4538 Since we would rather only read the local symbols once, and we
4539 would rather not keep them in memory, we handle all the
4540 relocations for a single input file at the same time.
4541
4542 Unfortunately, there is no way to know the total number of local
4543 symbols until we have seen all of them, and the local symbol
4544 indices precede the global symbol indices. This means that when
4545 we are generating relocateable output, and we see a reloc against
4546 a global symbol, we can not know the symbol index until we have
4547 finished examining all the local symbols to see which ones we are
4548 going to output. To deal with this, we keep the relocations in
4549 memory, and don't output them until the end of the link. This is
4550 an unfortunate waste of memory, but I don't see a good way around
4551 it. Fortunately, it only happens when performing a relocateable
4552 link, which is not the common case. FIXME: If keep_memory is set
4553 we could write the relocs out and then read them again; I don't
4554 know how bad the memory loss will be. */
4555
4556 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
4557 sub->output_has_begun = false;
4558 for (o = abfd->sections; o != NULL; o = o->next)
4559 {
4560 for (p = o->link_order_head; p != NULL; p = p->next)
4561 {
4562 if (p->type == bfd_indirect_link_order
4563 && (bfd_get_flavour (p->u.indirect.section->owner)
4564 == bfd_target_elf_flavour))
4565 {
4566 sub = p->u.indirect.section->owner;
4567 if (! sub->output_has_begun)
4568 {
4569 if (! elf_link_input_bfd (&finfo, sub))
4570 goto error_return;
4571 sub->output_has_begun = true;
4572 }
4573 }
4574 else if (p->type == bfd_section_reloc_link_order
4575 || p->type == bfd_symbol_reloc_link_order)
4576 {
4577 if (! elf_reloc_link_order (abfd, info, o, p))
4578 goto error_return;
4579 }
4580 else
4581 {
4582 if (! _bfd_default_link_order (abfd, info, o, p))
4583 goto error_return;
4584 }
4585 }
4586 }
4587
4588 /* That wrote out all the local symbols. Finish up the symbol table
4589 with the global symbols. Even if we want to strip everything we
4590 can, we still need to deal with those global symbols that got
4591 converted to local in a version script. */
4592
4593 if (info->shared)
4594 {
4595 /* Output any global symbols that got converted to local in a
4596 version script. We do this in a separate step since ELF
4597 requires all local symbols to appear prior to any global
4598 symbols. FIXME: We should only do this if some global
4599 symbols were, in fact, converted to become local. FIXME:
4600 Will this work correctly with the Irix 5 linker? */
4601 eoinfo.failed = false;
4602 eoinfo.finfo = &finfo;
4603 eoinfo.localsyms = true;
4604 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4605 (PTR) &eoinfo);
4606 if (eoinfo.failed)
4607 return false;
4608 }
4609
4610 /* The sh_info field records the index of the first non local symbol. */
4611 symtab_hdr->sh_info = bfd_get_symcount (abfd);
4612
4613 if (dynamic)
4614 {
4615 Elf_Internal_Sym sym;
4616 Elf_External_Sym *dynsym =
4617 (Elf_External_Sym *)finfo.dynsym_sec->contents;
4618 long last_local = 0;
4619
4620 /* Write out the section symbols for the output sections. */
4621 if (info->shared)
4622 {
4623 asection *s;
4624
4625 sym.st_size = 0;
4626 sym.st_name = 0;
4627 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
4628 sym.st_other = 0;
4629
4630 for (s = abfd->sections; s != NULL; s = s->next)
4631 {
4632 int indx;
4633 indx = elf_section_data (s)->this_idx;
4634 BFD_ASSERT (indx > 0);
4635 sym.st_shndx = indx;
4636 sym.st_value = s->vma;
4637
4638 elf_swap_symbol_out (abfd, &sym,
4639 dynsym + elf_section_data (s)->dynindx);
4640 }
4641
4642 last_local = bfd_count_sections (abfd);
4643 }
4644
4645 /* Write out the local dynsyms. */
4646 if (elf_hash_table (info)->dynlocal)
4647 {
4648 struct elf_link_local_dynamic_entry *e;
4649 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
4650 {
4651 asection *s;
4652
4653 sym.st_size = e->isym.st_size;
4654 sym.st_other = e->isym.st_other;
4655
4656 /* Copy the internal symbol as is.
4657 Note that we saved a word of storage and overwrote
4658 the original st_name with the dynstr_index. */
4659 sym = e->isym;
4660
4661 if (e->isym.st_shndx > 0 && e->isym.st_shndx < SHN_LORESERVE)
4662 {
4663 s = bfd_section_from_elf_index (e->input_bfd,
4664 e->isym.st_shndx);
4665
4666 sym.st_shndx =
4667 elf_section_data (s->output_section)->this_idx;
4668 sym.st_value = (s->output_section->vma
4669 + s->output_offset
4670 + e->isym.st_value);
4671 }
4672
4673 if (last_local < e->dynindx)
4674 last_local = e->dynindx;
4675
4676 elf_swap_symbol_out (abfd, &sym, dynsym + e->dynindx);
4677 }
4678 }
4679
4680 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
4681 last_local + 1;
4682 }
4683
4684 /* We get the global symbols from the hash table. */
4685 eoinfo.failed = false;
4686 eoinfo.localsyms = false;
4687 eoinfo.finfo = &finfo;
4688 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
4689 (PTR) &eoinfo);
4690 if (eoinfo.failed)
4691 return false;
4692
4693 /* If backend needs to output some symbols not present in the hash
4694 table, do it now. */
4695 if (bed->elf_backend_output_arch_syms)
4696 {
4697 if (! (*bed->elf_backend_output_arch_syms)
4698 (abfd, info, (PTR) &finfo,
4699 (boolean (*) PARAMS ((PTR, const char *,
4700 Elf_Internal_Sym *, asection *)))
4701 elf_link_output_sym))
4702 return false;
4703 }
4704
4705 /* Flush all symbols to the file. */
4706 if (! elf_link_flush_output_syms (&finfo))
4707 return false;
4708
4709 /* Now we know the size of the symtab section. */
4710 off += symtab_hdr->sh_size;
4711
4712 /* Finish up and write out the symbol string table (.strtab)
4713 section. */
4714 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
4715 /* sh_name was set in prep_headers. */
4716 symstrtab_hdr->sh_type = SHT_STRTAB;
4717 symstrtab_hdr->sh_flags = 0;
4718 symstrtab_hdr->sh_addr = 0;
4719 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
4720 symstrtab_hdr->sh_entsize = 0;
4721 symstrtab_hdr->sh_link = 0;
4722 symstrtab_hdr->sh_info = 0;
4723 /* sh_offset is set just below. */
4724 symstrtab_hdr->sh_addralign = 1;
4725
4726 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true);
4727 elf_tdata (abfd)->next_file_pos = off;
4728
4729 if (bfd_get_symcount (abfd) > 0)
4730 {
4731 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
4732 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
4733 return false;
4734 }
4735
4736 /* Adjust the relocs to have the correct symbol indices. */
4737 for (o = abfd->sections; o != NULL; o = o->next)
4738 {
4739 if ((o->flags & SEC_RELOC) == 0)
4740 continue;
4741
4742 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
4743 elf_section_data (o)->rel_count,
4744 elf_section_data (o)->rel_hashes);
4745 if (elf_section_data (o)->rel_hdr2 != NULL)
4746 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
4747 elf_section_data (o)->rel_count2,
4748 (elf_section_data (o)->rel_hashes
4749 + elf_section_data (o)->rel_count));
4750
4751 /* Set the reloc_count field to 0 to prevent write_relocs from
4752 trying to swap the relocs out itself. */
4753 o->reloc_count = 0;
4754 }
4755
4756 /* If we are linking against a dynamic object, or generating a
4757 shared library, finish up the dynamic linking information. */
4758 if (dynamic)
4759 {
4760 Elf_External_Dyn *dyncon, *dynconend;
4761
4762 /* Fix up .dynamic entries. */
4763 o = bfd_get_section_by_name (dynobj, ".dynamic");
4764 BFD_ASSERT (o != NULL);
4765
4766 dyncon = (Elf_External_Dyn *) o->contents;
4767 dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size);
4768 for (; dyncon < dynconend; dyncon++)
4769 {
4770 Elf_Internal_Dyn dyn;
4771 const char *name;
4772 unsigned int type;
4773
4774 elf_swap_dyn_in (dynobj, dyncon, &dyn);
4775
4776 switch (dyn.d_tag)
4777 {
4778 default:
4779 break;
4780 case DT_INIT:
4781 name = info->init_function;
4782 goto get_sym;
4783 case DT_FINI:
4784 name = info->fini_function;
4785 get_sym:
4786 {
4787 struct elf_link_hash_entry *h;
4788
4789 h = elf_link_hash_lookup (elf_hash_table (info), name,
4790 false, false, true);
4791 if (h != NULL
4792 && (h->root.type == bfd_link_hash_defined
4793 || h->root.type == bfd_link_hash_defweak))
4794 {
4795 dyn.d_un.d_val = h->root.u.def.value;
4796 o = h->root.u.def.section;
4797 if (o->output_section != NULL)
4798 dyn.d_un.d_val += (o->output_section->vma
4799 + o->output_offset);
4800 else
4801 {
4802 /* The symbol is imported from another shared
4803 library and does not apply to this one. */
4804 dyn.d_un.d_val = 0;
4805 }
4806
4807 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4808 }
4809 }
4810 break;
4811
4812 case DT_HASH:
4813 name = ".hash";
4814 goto get_vma;
4815 case DT_STRTAB:
4816 name = ".dynstr";
4817 goto get_vma;
4818 case DT_SYMTAB:
4819 name = ".dynsym";
4820 goto get_vma;
4821 case DT_VERDEF:
4822 name = ".gnu.version_d";
4823 goto get_vma;
4824 case DT_VERNEED:
4825 name = ".gnu.version_r";
4826 goto get_vma;
4827 case DT_VERSYM:
4828 name = ".gnu.version";
4829 get_vma:
4830 o = bfd_get_section_by_name (abfd, name);
4831 BFD_ASSERT (o != NULL);
4832 dyn.d_un.d_ptr = o->vma;
4833 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4834 break;
4835
4836 case DT_REL:
4837 case DT_RELA:
4838 case DT_RELSZ:
4839 case DT_RELASZ:
4840 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
4841 type = SHT_REL;
4842 else
4843 type = SHT_RELA;
4844 dyn.d_un.d_val = 0;
4845 for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++)
4846 {
4847 Elf_Internal_Shdr *hdr;
4848
4849 hdr = elf_elfsections (abfd)[i];
4850 if (hdr->sh_type == type
4851 && (hdr->sh_flags & SHF_ALLOC) != 0)
4852 {
4853 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
4854 dyn.d_un.d_val += hdr->sh_size;
4855 else
4856 {
4857 if (dyn.d_un.d_val == 0
4858 || hdr->sh_addr < dyn.d_un.d_val)
4859 dyn.d_un.d_val = hdr->sh_addr;
4860 }
4861 }
4862 }
4863 elf_swap_dyn_out (dynobj, &dyn, dyncon);
4864 break;
4865 }
4866 }
4867 }
4868
4869 /* If we have created any dynamic sections, then output them. */
4870 if (dynobj != NULL)
4871 {
4872 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
4873 goto error_return;
4874
4875 for (o = dynobj->sections; o != NULL; o = o->next)
4876 {
4877 if ((o->flags & SEC_HAS_CONTENTS) == 0
4878 || o->_raw_size == 0)
4879 continue;
4880 if ((o->flags & SEC_LINKER_CREATED) == 0)
4881 {
4882 /* At this point, we are only interested in sections
4883 created by elf_link_create_dynamic_sections. */
4884 continue;
4885 }
4886 if ((elf_section_data (o->output_section)->this_hdr.sh_type
4887 != SHT_STRTAB)
4888 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
4889 {
4890 if (! bfd_set_section_contents (abfd, o->output_section,
4891 o->contents, o->output_offset,
4892 o->_raw_size))
4893 goto error_return;
4894 }
4895 else
4896 {
4897 file_ptr off;
4898
4899 /* The contents of the .dynstr section are actually in a
4900 stringtab. */
4901 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
4902 if (bfd_seek (abfd, off, SEEK_SET) != 0
4903 || ! _bfd_stringtab_emit (abfd,
4904 elf_hash_table (info)->dynstr))
4905 goto error_return;
4906 }
4907 }
4908 }
4909
4910 /* If we have optimized stabs strings, output them. */
4911 if (elf_hash_table (info)->stab_info != NULL)
4912 {
4913 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
4914 goto error_return;
4915 }
4916
4917 if (finfo.symstrtab != NULL)
4918 _bfd_stringtab_free (finfo.symstrtab);
4919 if (finfo.contents != NULL)
4920 free (finfo.contents);
4921 if (finfo.external_relocs != NULL)
4922 free (finfo.external_relocs);
4923 if (finfo.internal_relocs != NULL)
4924 free (finfo.internal_relocs);
4925 if (finfo.external_syms != NULL)
4926 free (finfo.external_syms);
4927 if (finfo.internal_syms != NULL)
4928 free (finfo.internal_syms);
4929 if (finfo.indices != NULL)
4930 free (finfo.indices);
4931 if (finfo.sections != NULL)
4932 free (finfo.sections);
4933 if (finfo.symbuf != NULL)
4934 free (finfo.symbuf);
4935 for (o = abfd->sections; o != NULL; o = o->next)
4936 {
4937 if ((o->flags & SEC_RELOC) != 0
4938 && elf_section_data (o)->rel_hashes != NULL)
4939 free (elf_section_data (o)->rel_hashes);
4940 }
4941
4942 elf_tdata (abfd)->linker = true;
4943
4944 return true;
4945
4946 error_return:
4947 if (finfo.symstrtab != NULL)
4948 _bfd_stringtab_free (finfo.symstrtab);
4949 if (finfo.contents != NULL)
4950 free (finfo.contents);
4951 if (finfo.external_relocs != NULL)
4952 free (finfo.external_relocs);
4953 if (finfo.internal_relocs != NULL)
4954 free (finfo.internal_relocs);
4955 if (finfo.external_syms != NULL)
4956 free (finfo.external_syms);
4957 if (finfo.internal_syms != NULL)
4958 free (finfo.internal_syms);
4959 if (finfo.indices != NULL)
4960 free (finfo.indices);
4961 if (finfo.sections != NULL)
4962 free (finfo.sections);
4963 if (finfo.symbuf != NULL)
4964 free (finfo.symbuf);
4965 for (o = abfd->sections; o != NULL; o = o->next)
4966 {
4967 if ((o->flags & SEC_RELOC) != 0
4968 && elf_section_data (o)->rel_hashes != NULL)
4969 free (elf_section_data (o)->rel_hashes);
4970 }
4971
4972 return false;
4973 }
4974
4975 /* Add a symbol to the output symbol table. */
4976
4977 static boolean
4978 elf_link_output_sym (finfo, name, elfsym, input_sec)
4979 struct elf_final_link_info *finfo;
4980 const char *name;
4981 Elf_Internal_Sym *elfsym;
4982 asection *input_sec;
4983 {
4984 boolean (*output_symbol_hook) PARAMS ((bfd *,
4985 struct bfd_link_info *info,
4986 const char *,
4987 Elf_Internal_Sym *,
4988 asection *));
4989
4990 output_symbol_hook = get_elf_backend_data (finfo->output_bfd)->
4991 elf_backend_link_output_symbol_hook;
4992 if (output_symbol_hook != NULL)
4993 {
4994 if (! ((*output_symbol_hook)
4995 (finfo->output_bfd, finfo->info, name, elfsym, input_sec)))
4996 return false;
4997 }
4998
4999 if (name == (const char *) NULL || *name == '\0')
5000 elfsym->st_name = 0;
5001 else if (input_sec->flags & SEC_EXCLUDE)
5002 elfsym->st_name = 0;
5003 else
5004 {
5005 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
5006 name, true,
5007 false);
5008 if (elfsym->st_name == (unsigned long) -1)
5009 return false;
5010 }
5011
5012 if (finfo->symbuf_count >= finfo->symbuf_size)
5013 {
5014 if (! elf_link_flush_output_syms (finfo))
5015 return false;
5016 }
5017
5018 elf_swap_symbol_out (finfo->output_bfd, elfsym,
5019 (PTR) (finfo->symbuf + finfo->symbuf_count));
5020 ++finfo->symbuf_count;
5021
5022 ++ bfd_get_symcount (finfo->output_bfd);
5023
5024 return true;
5025 }
5026
5027 /* Flush the output symbols to the file. */
5028
5029 static boolean
5030 elf_link_flush_output_syms (finfo)
5031 struct elf_final_link_info *finfo;
5032 {
5033 if (finfo->symbuf_count > 0)
5034 {
5035 Elf_Internal_Shdr *symtab;
5036
5037 symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr;
5038
5039 if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size,
5040 SEEK_SET) != 0
5041 || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count,
5042 sizeof (Elf_External_Sym), finfo->output_bfd)
5043 != finfo->symbuf_count * sizeof (Elf_External_Sym)))
5044 return false;
5045
5046 symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym);
5047
5048 finfo->symbuf_count = 0;
5049 }
5050
5051 return true;
5052 }
5053
5054 /* Add an external symbol to the symbol table. This is called from
5055 the hash table traversal routine. When generating a shared object,
5056 we go through the symbol table twice. The first time we output
5057 anything that might have been forced to local scope in a version
5058 script. The second time we output the symbols that are still
5059 global symbols. */
5060
5061 static boolean
5062 elf_link_output_extsym (h, data)
5063 struct elf_link_hash_entry *h;
5064 PTR data;
5065 {
5066 struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
5067 struct elf_final_link_info *finfo = eoinfo->finfo;
5068 boolean strip;
5069 Elf_Internal_Sym sym;
5070 asection *input_sec;
5071
5072 /* Decide whether to output this symbol in this pass. */
5073 if (eoinfo->localsyms)
5074 {
5075 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5076 return true;
5077 }
5078 else
5079 {
5080 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5081 return true;
5082 }
5083
5084 /* If we are not creating a shared library, and this symbol is
5085 referenced by a shared library but is not defined anywhere, then
5086 warn that it is undefined. If we do not do this, the runtime
5087 linker will complain that the symbol is undefined when the
5088 program is run. We don't have to worry about symbols that are
5089 referenced by regular files, because we will already have issued
5090 warnings for them. */
5091 if (! finfo->info->relocateable
5092 && ! (finfo->info->shared
5093 && !finfo->info->no_undefined)
5094 && h->root.type == bfd_link_hash_undefined
5095 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0
5096 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5097 {
5098 if (! ((*finfo->info->callbacks->undefined_symbol)
5099 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
5100 (asection *) NULL, 0, true)))
5101 {
5102 eoinfo->failed = true;
5103 return false;
5104 }
5105 }
5106
5107 /* We don't want to output symbols that have never been mentioned by
5108 a regular file, or that we have been told to strip. However, if
5109 h->indx is set to -2, the symbol is used by a reloc and we must
5110 output it. */
5111 if (h->indx == -2)
5112 strip = false;
5113 else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
5114 || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0)
5115 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0
5116 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)
5117 strip = true;
5118 else if (finfo->info->strip == strip_all
5119 || (finfo->info->strip == strip_some
5120 && bfd_hash_lookup (finfo->info->keep_hash,
5121 h->root.root.string,
5122 false, false) == NULL))
5123 strip = true;
5124 else
5125 strip = false;
5126
5127 /* If we're stripping it, and it's not a dynamic symbol, there's
5128 nothing else to do unless it is a forced local symbol. */
5129 if (strip
5130 && h->dynindx == -1
5131 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
5132 return true;
5133
5134 sym.st_value = 0;
5135 sym.st_size = h->size;
5136 sym.st_other = h->other;
5137 if ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5138 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
5139 else if (h->root.type == bfd_link_hash_undefweak
5140 || h->root.type == bfd_link_hash_defweak)
5141 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
5142 else
5143 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
5144
5145 switch (h->root.type)
5146 {
5147 default:
5148 case bfd_link_hash_new:
5149 abort ();
5150 return false;
5151
5152 case bfd_link_hash_undefined:
5153 input_sec = bfd_und_section_ptr;
5154 sym.st_shndx = SHN_UNDEF;
5155 break;
5156
5157 case bfd_link_hash_undefweak:
5158 input_sec = bfd_und_section_ptr;
5159 sym.st_shndx = SHN_UNDEF;
5160 break;
5161
5162 case bfd_link_hash_defined:
5163 case bfd_link_hash_defweak:
5164 {
5165 input_sec = h->root.u.def.section;
5166 if (input_sec->output_section != NULL)
5167 {
5168 sym.st_shndx =
5169 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
5170 input_sec->output_section);
5171 if (sym.st_shndx == (unsigned short) -1)
5172 {
5173 (*_bfd_error_handler)
5174 (_("%s: could not find output section %s for input section %s"),
5175 bfd_get_filename (finfo->output_bfd),
5176 input_sec->output_section->name,
5177 input_sec->name);
5178 eoinfo->failed = true;
5179 return false;
5180 }
5181
5182 /* ELF symbols in relocateable files are section relative,
5183 but in nonrelocateable files they are virtual
5184 addresses. */
5185 sym.st_value = h->root.u.def.value + input_sec->output_offset;
5186 if (! finfo->info->relocateable)
5187 sym.st_value += input_sec->output_section->vma;
5188 }
5189 else
5190 {
5191 BFD_ASSERT (input_sec->owner == NULL
5192 || (input_sec->owner->flags & DYNAMIC) != 0);
5193 sym.st_shndx = SHN_UNDEF;
5194 input_sec = bfd_und_section_ptr;
5195 }
5196 }
5197 break;
5198
5199 case bfd_link_hash_common:
5200 input_sec = h->root.u.c.p->section;
5201 sym.st_shndx = SHN_COMMON;
5202 sym.st_value = 1 << h->root.u.c.p->alignment_power;
5203 break;
5204
5205 case bfd_link_hash_indirect:
5206 /* These symbols are created by symbol versioning. They point
5207 to the decorated version of the name. For example, if the
5208 symbol foo@@GNU_1.2 is the default, which should be used when
5209 foo is used with no version, then we add an indirect symbol
5210 foo which points to foo@@GNU_1.2. We ignore these symbols,
5211 since the indirected symbol is already in the hash table. */
5212 return true;
5213
5214 case bfd_link_hash_warning:
5215 /* We can't represent these symbols in ELF, although a warning
5216 symbol may have come from a .gnu.warning.SYMBOL section. We
5217 just put the target symbol in the hash table. If the target
5218 symbol does not really exist, don't do anything. */
5219 if (h->root.u.i.link->type == bfd_link_hash_new)
5220 return true;
5221 return (elf_link_output_extsym
5222 ((struct elf_link_hash_entry *) h->root.u.i.link, data));
5223 }
5224
5225 /* Give the processor backend a chance to tweak the symbol value,
5226 and also to finish up anything that needs to be done for this
5227 symbol. */
5228 if ((h->dynindx != -1
5229 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0)
5230 && elf_hash_table (finfo->info)->dynamic_sections_created)
5231 {
5232 struct elf_backend_data *bed;
5233
5234 bed = get_elf_backend_data (finfo->output_bfd);
5235 if (! ((*bed->elf_backend_finish_dynamic_symbol)
5236 (finfo->output_bfd, finfo->info, h, &sym)))
5237 {
5238 eoinfo->failed = true;
5239 return false;
5240 }
5241 }
5242
5243 /* If we are marking the symbol as undefined, and there are no
5244 non-weak references to this symbol from a regular object, then
5245 mark the symbol as weak undefined; if there are non-weak
5246 references, mark the symbol as strong. We can't do this earlier,
5247 because it might not be marked as undefined until the
5248 finish_dynamic_symbol routine gets through with it. */
5249 if (sym.st_shndx == SHN_UNDEF
5250 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) != 0
5251 && (ELF_ST_BIND(sym.st_info) == STB_GLOBAL
5252 || ELF_ST_BIND(sym.st_info) == STB_WEAK))
5253 {
5254 int bindtype;
5255
5256 if ((h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR_NONWEAK) != 0)
5257 bindtype = STB_GLOBAL;
5258 else
5259 bindtype = STB_WEAK;
5260 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
5261 }
5262
5263 /* If a symbol is not defined locally, we clear the visibility
5264 field. */
5265 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5266 sym.st_other ^= ELF_ST_VISIBILITY(sym.st_other);
5267
5268 /* If this symbol should be put in the .dynsym section, then put it
5269 there now. We have already know the symbol index. We also fill
5270 in the entry in the .hash section. */
5271 if (h->dynindx != -1
5272 && elf_hash_table (finfo->info)->dynamic_sections_created)
5273 {
5274 size_t bucketcount;
5275 size_t bucket;
5276 size_t hash_entry_size;
5277 bfd_byte *bucketpos;
5278 bfd_vma chain;
5279
5280 sym.st_name = h->dynstr_index;
5281
5282 elf_swap_symbol_out (finfo->output_bfd, &sym,
5283 (PTR) (((Elf_External_Sym *)
5284 finfo->dynsym_sec->contents)
5285 + h->dynindx));
5286
5287 bucketcount = elf_hash_table (finfo->info)->bucketcount;
5288 bucket = h->elf_hash_value % bucketcount;
5289 hash_entry_size
5290 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
5291 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
5292 + (bucket + 2) * hash_entry_size);
5293 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
5294 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
5295 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
5296 ((bfd_byte *) finfo->hash_sec->contents
5297 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
5298
5299 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
5300 {
5301 Elf_Internal_Versym iversym;
5302
5303 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
5304 {
5305 if (h->verinfo.verdef == NULL)
5306 iversym.vs_vers = 0;
5307 else
5308 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
5309 }
5310 else
5311 {
5312 if (h->verinfo.vertree == NULL)
5313 iversym.vs_vers = 1;
5314 else
5315 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
5316 }
5317
5318 if ((h->elf_link_hash_flags & ELF_LINK_HIDDEN) != 0)
5319 iversym.vs_vers |= VERSYM_HIDDEN;
5320
5321 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym,
5322 (((Elf_External_Versym *)
5323 finfo->symver_sec->contents)
5324 + h->dynindx));
5325 }
5326 }
5327
5328 /* If we're stripping it, then it was just a dynamic symbol, and
5329 there's nothing else to do. */
5330 if (strip)
5331 return true;
5332
5333 h->indx = bfd_get_symcount (finfo->output_bfd);
5334
5335 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec))
5336 {
5337 eoinfo->failed = true;
5338 return false;
5339 }
5340
5341 return true;
5342 }
5343
5344 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
5345 originated from the section given by INPUT_REL_HDR) to the
5346 OUTPUT_BFD. */
5347
5348 static void
5349 elf_link_output_relocs (output_bfd, input_section, input_rel_hdr,
5350 internal_relocs)
5351 bfd *output_bfd;
5352 asection *input_section;
5353 Elf_Internal_Shdr *input_rel_hdr;
5354 Elf_Internal_Rela *internal_relocs;
5355 {
5356 Elf_Internal_Rela *irela;
5357 Elf_Internal_Rela *irelaend;
5358 Elf_Internal_Shdr *output_rel_hdr;
5359 asection *output_section;
5360 unsigned int *rel_countp = NULL;
5361 struct elf_backend_data *bed;
5362
5363 output_section = input_section->output_section;
5364 output_rel_hdr = NULL;
5365
5366 if (elf_section_data (output_section)->rel_hdr.sh_entsize
5367 == input_rel_hdr->sh_entsize)
5368 {
5369 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
5370 rel_countp = &elf_section_data (output_section)->rel_count;
5371 }
5372 else if (elf_section_data (output_section)->rel_hdr2
5373 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
5374 == input_rel_hdr->sh_entsize))
5375 {
5376 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
5377 rel_countp = &elf_section_data (output_section)->rel_count2;
5378 }
5379
5380 BFD_ASSERT (output_rel_hdr != NULL);
5381
5382 bed = get_elf_backend_data (output_bfd);
5383 irela = internal_relocs;
5384 irelaend = irela + input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5385 if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel))
5386 {
5387 Elf_External_Rel *erel;
5388
5389 erel = ((Elf_External_Rel *) output_rel_hdr->contents + *rel_countp);
5390 for (; irela < irelaend; irela++, erel++)
5391 {
5392 Elf_Internal_Rel irel;
5393
5394 irel.r_offset = irela->r_offset;
5395 irel.r_info = irela->r_info;
5396 BFD_ASSERT (irela->r_addend == 0);
5397 if (bed->s->swap_reloc_out)
5398 (*bed->s->swap_reloc_out) (output_bfd, &irel, (PTR) erel);
5399 else
5400 elf_swap_reloc_out (output_bfd, &irel, erel);
5401 }
5402 }
5403 else
5404 {
5405 Elf_External_Rela *erela;
5406
5407 BFD_ASSERT (input_rel_hdr->sh_entsize
5408 == sizeof (Elf_External_Rela));
5409 erela = ((Elf_External_Rela *) output_rel_hdr->contents + *rel_countp);
5410 for (; irela < irelaend; irela++, erela++)
5411 if (bed->s->swap_reloca_out)
5412 (*bed->s->swap_reloca_out) (output_bfd, irela, (PTR) erela);
5413 else
5414 elf_swap_reloca_out (output_bfd, irela, erela);
5415 }
5416
5417 /* Bump the counter, so that we know where to add the next set of
5418 relocations. */
5419 *rel_countp += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5420 }
5421
5422 /* Link an input file into the linker output file. This function
5423 handles all the sections and relocations of the input file at once.
5424 This is so that we only have to read the local symbols once, and
5425 don't have to keep them in memory. */
5426
5427 static boolean
5428 elf_link_input_bfd (finfo, input_bfd)
5429 struct elf_final_link_info *finfo;
5430 bfd *input_bfd;
5431 {
5432 boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *,
5433 bfd *, asection *, bfd_byte *,
5434 Elf_Internal_Rela *,
5435 Elf_Internal_Sym *, asection **));
5436 bfd *output_bfd;
5437 Elf_Internal_Shdr *symtab_hdr;
5438 size_t locsymcount;
5439 size_t extsymoff;
5440 Elf_External_Sym *external_syms;
5441 Elf_External_Sym *esym;
5442 Elf_External_Sym *esymend;
5443 Elf_Internal_Sym *isym;
5444 long *pindex;
5445 asection **ppsection;
5446 asection *o;
5447 struct elf_backend_data *bed;
5448
5449 output_bfd = finfo->output_bfd;
5450 bed = get_elf_backend_data (output_bfd);
5451 relocate_section = bed->elf_backend_relocate_section;
5452
5453 /* If this is a dynamic object, we don't want to do anything here:
5454 we don't want the local symbols, and we don't want the section
5455 contents. */
5456 if ((input_bfd->flags & DYNAMIC) != 0)
5457 return true;
5458
5459 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
5460 if (elf_bad_symtab (input_bfd))
5461 {
5462 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
5463 extsymoff = 0;
5464 }
5465 else
5466 {
5467 locsymcount = symtab_hdr->sh_info;
5468 extsymoff = symtab_hdr->sh_info;
5469 }
5470
5471 /* Read the local symbols. */
5472 if (symtab_hdr->contents != NULL)
5473 external_syms = (Elf_External_Sym *) symtab_hdr->contents;
5474 else if (locsymcount == 0)
5475 external_syms = NULL;
5476 else
5477 {
5478 external_syms = finfo->external_syms;
5479 if (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
5480 || (bfd_read (external_syms, sizeof (Elf_External_Sym),
5481 locsymcount, input_bfd)
5482 != locsymcount * sizeof (Elf_External_Sym)))
5483 return false;
5484 }
5485
5486 /* Swap in the local symbols and write out the ones which we know
5487 are going into the output file. */
5488 esym = external_syms;
5489 esymend = esym + locsymcount;
5490 isym = finfo->internal_syms;
5491 pindex = finfo->indices;
5492 ppsection = finfo->sections;
5493 for (; esym < esymend; esym++, isym++, pindex++, ppsection++)
5494 {
5495 asection *isec;
5496 const char *name;
5497 Elf_Internal_Sym osym;
5498
5499 elf_swap_symbol_in (input_bfd, esym, isym);
5500 *pindex = -1;
5501
5502 if (elf_bad_symtab (input_bfd))
5503 {
5504 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
5505 {
5506 *ppsection = NULL;
5507 continue;
5508 }
5509 }
5510
5511 if (isym->st_shndx == SHN_UNDEF)
5512 isec = bfd_und_section_ptr;
5513 else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE)
5514 isec = section_from_elf_index (input_bfd, isym->st_shndx);
5515 else if (isym->st_shndx == SHN_ABS)
5516 isec = bfd_abs_section_ptr;
5517 else if (isym->st_shndx == SHN_COMMON)
5518 isec = bfd_com_section_ptr;
5519 else
5520 {
5521 /* Who knows? */
5522 isec = NULL;
5523 }
5524
5525 *ppsection = isec;
5526
5527 /* Don't output the first, undefined, symbol. */
5528 if (esym == external_syms)
5529 continue;
5530
5531 /* If we are stripping all symbols, we don't want to output this
5532 one. */
5533 if (finfo->info->strip == strip_all)
5534 continue;
5535
5536 /* We never output section symbols. Instead, we use the section
5537 symbol of the corresponding section in the output file. */
5538 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5539 continue;
5540
5541 /* If we are discarding all local symbols, we don't want to
5542 output this one. If we are generating a relocateable output
5543 file, then some of the local symbols may be required by
5544 relocs; we output them below as we discover that they are
5545 needed. */
5546 if (finfo->info->discard == discard_all)
5547 continue;
5548
5549 /* If this symbol is defined in a section which we are
5550 discarding, we don't need to keep it, but note that
5551 linker_mark is only reliable for sections that have contents.
5552 For the benefit of the MIPS ELF linker, we check SEC_EXCLUDE
5553 as well as linker_mark. */
5554 if (isym->st_shndx > 0
5555 && isym->st_shndx < SHN_LORESERVE
5556 && isec != NULL
5557 && ((! isec->linker_mark && (isec->flags & SEC_HAS_CONTENTS) != 0)
5558 || (! finfo->info->relocateable
5559 && (isec->flags & SEC_EXCLUDE) != 0)))
5560 continue;
5561
5562 /* Get the name of the symbol. */
5563 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
5564 isym->st_name);
5565 if (name == NULL)
5566 return false;
5567
5568 /* See if we are discarding symbols with this name. */
5569 if ((finfo->info->strip == strip_some
5570 && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false)
5571 == NULL))
5572 || (finfo->info->discard == discard_l
5573 && bfd_is_local_label_name (input_bfd, name)))
5574 continue;
5575
5576 /* If we get here, we are going to output this symbol. */
5577
5578 osym = *isym;
5579
5580 /* Adjust the section index for the output file. */
5581 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
5582 isec->output_section);
5583 if (osym.st_shndx == (unsigned short) -1)
5584 return false;
5585
5586 *pindex = bfd_get_symcount (output_bfd);
5587
5588 /* ELF symbols in relocateable files are section relative, but
5589 in executable files they are virtual addresses. Note that
5590 this code assumes that all ELF sections have an associated
5591 BFD section with a reasonable value for output_offset; below
5592 we assume that they also have a reasonable value for
5593 output_section. Any special sections must be set up to meet
5594 these requirements. */
5595 osym.st_value += isec->output_offset;
5596 if (! finfo->info->relocateable)
5597 osym.st_value += isec->output_section->vma;
5598
5599 if (! elf_link_output_sym (finfo, name, &osym, isec))
5600 return false;
5601 }
5602
5603 /* Relocate the contents of each section. */
5604 for (o = input_bfd->sections; o != NULL; o = o->next)
5605 {
5606 bfd_byte *contents;
5607
5608 if (! o->linker_mark)
5609 {
5610 /* This section was omitted from the link. */
5611 continue;
5612 }
5613
5614 if ((o->flags & SEC_HAS_CONTENTS) == 0
5615 || (o->_raw_size == 0 && (o->flags & SEC_RELOC) == 0))
5616 continue;
5617
5618 if ((o->flags & SEC_LINKER_CREATED) != 0)
5619 {
5620 /* Section was created by elf_link_create_dynamic_sections
5621 or somesuch. */
5622 continue;
5623 }
5624
5625 /* Get the contents of the section. They have been cached by a
5626 relaxation routine. Note that o is a section in an input
5627 file, so the contents field will not have been set by any of
5628 the routines which work on output files. */
5629 if (elf_section_data (o)->this_hdr.contents != NULL)
5630 contents = elf_section_data (o)->this_hdr.contents;
5631 else
5632 {
5633 contents = finfo->contents;
5634 if (! bfd_get_section_contents (input_bfd, o, contents,
5635 (file_ptr) 0, o->_raw_size))
5636 return false;
5637 }
5638
5639 if ((o->flags & SEC_RELOC) != 0)
5640 {
5641 Elf_Internal_Rela *internal_relocs;
5642
5643 /* Get the swapped relocs. */
5644 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
5645 (input_bfd, o, finfo->external_relocs,
5646 finfo->internal_relocs, false));
5647 if (internal_relocs == NULL
5648 && o->reloc_count > 0)
5649 return false;
5650
5651 /* Relocate the section by invoking a back end routine.
5652
5653 The back end routine is responsible for adjusting the
5654 section contents as necessary, and (if using Rela relocs
5655 and generating a relocateable output file) adjusting the
5656 reloc addend as necessary.
5657
5658 The back end routine does not have to worry about setting
5659 the reloc address or the reloc symbol index.
5660
5661 The back end routine is given a pointer to the swapped in
5662 internal symbols, and can access the hash table entries
5663 for the external symbols via elf_sym_hashes (input_bfd).
5664
5665 When generating relocateable output, the back end routine
5666 must handle STB_LOCAL/STT_SECTION symbols specially. The
5667 output symbol is going to be a section symbol
5668 corresponding to the output section, which will require
5669 the addend to be adjusted. */
5670
5671 if (! (*relocate_section) (output_bfd, finfo->info,
5672 input_bfd, o, contents,
5673 internal_relocs,
5674 finfo->internal_syms,
5675 finfo->sections))
5676 return false;
5677
5678 if (finfo->info->relocateable || finfo->info->emitrelocations)
5679 {
5680 Elf_Internal_Rela *irela;
5681 Elf_Internal_Rela *irelaend;
5682 struct elf_link_hash_entry **rel_hash;
5683 Elf_Internal_Shdr *input_rel_hdr;
5684
5685 /* Adjust the reloc addresses and symbol indices. */
5686
5687 irela = internal_relocs;
5688 irelaend =
5689 irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
5690 rel_hash = (elf_section_data (o->output_section)->rel_hashes
5691 + elf_section_data (o->output_section)->rel_count
5692 + elf_section_data (o->output_section)->rel_count2);
5693 for (; irela < irelaend; irela++, rel_hash++)
5694 {
5695 unsigned long r_symndx;
5696 Elf_Internal_Sym *isym;
5697 asection *sec;
5698
5699 irela->r_offset += o->output_offset;
5700
5701 /* Relocs in an executable have to be virtual addresses. */
5702 if (finfo->info->emitrelocations)
5703 irela->r_offset += o->output_section->vma;
5704
5705 r_symndx = ELF_R_SYM (irela->r_info);
5706
5707 if (r_symndx == 0)
5708 continue;
5709
5710 if (r_symndx >= locsymcount
5711 || (elf_bad_symtab (input_bfd)
5712 && finfo->sections[r_symndx] == NULL))
5713 {
5714 struct elf_link_hash_entry *rh;
5715 long indx;
5716
5717 /* This is a reloc against a global symbol. We
5718 have not yet output all the local symbols, so
5719 we do not know the symbol index of any global
5720 symbol. We set the rel_hash entry for this
5721 reloc to point to the global hash table entry
5722 for this symbol. The symbol index is then
5723 set at the end of elf_bfd_final_link. */
5724 indx = r_symndx - extsymoff;
5725 rh = elf_sym_hashes (input_bfd)[indx];
5726 while (rh->root.type == bfd_link_hash_indirect
5727 || rh->root.type == bfd_link_hash_warning)
5728 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
5729
5730 /* Setting the index to -2 tells
5731 elf_link_output_extsym that this symbol is
5732 used by a reloc. */
5733 BFD_ASSERT (rh->indx < 0);
5734 rh->indx = -2;
5735
5736 *rel_hash = rh;
5737
5738 continue;
5739 }
5740
5741 /* This is a reloc against a local symbol. */
5742
5743 *rel_hash = NULL;
5744 isym = finfo->internal_syms + r_symndx;
5745 sec = finfo->sections[r_symndx];
5746 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
5747 {
5748 /* I suppose the backend ought to fill in the
5749 section of any STT_SECTION symbol against a
5750 processor specific section. If we have
5751 discarded a section, the output_section will
5752 be the absolute section. */
5753 if (sec != NULL
5754 && (bfd_is_abs_section (sec)
5755 || (sec->output_section != NULL
5756 && bfd_is_abs_section (sec->output_section))))
5757 r_symndx = 0;
5758 else if (sec == NULL || sec->owner == NULL)
5759 {
5760 bfd_set_error (bfd_error_bad_value);
5761 return false;
5762 }
5763 else
5764 {
5765 r_symndx = sec->output_section->target_index;
5766 BFD_ASSERT (r_symndx != 0);
5767 }
5768 }
5769 else
5770 {
5771 if (finfo->indices[r_symndx] == -1)
5772 {
5773 unsigned long link;
5774 const char *name;
5775 asection *osec;
5776
5777 if (finfo->info->strip == strip_all)
5778 {
5779 /* You can't do ld -r -s. */
5780 bfd_set_error (bfd_error_invalid_operation);
5781 return false;
5782 }
5783
5784 /* This symbol was skipped earlier, but
5785 since it is needed by a reloc, we
5786 must output it now. */
5787 link = symtab_hdr->sh_link;
5788 name = bfd_elf_string_from_elf_section (input_bfd,
5789 link,
5790 isym->st_name);
5791 if (name == NULL)
5792 return false;
5793
5794 osec = sec->output_section;
5795 isym->st_shndx =
5796 _bfd_elf_section_from_bfd_section (output_bfd,
5797 osec);
5798 if (isym->st_shndx == (unsigned short) -1)
5799 return false;
5800
5801 isym->st_value += sec->output_offset;
5802 if (! finfo->info->relocateable)
5803 isym->st_value += osec->vma;
5804
5805 finfo->indices[r_symndx] = bfd_get_symcount (output_bfd);
5806
5807 if (! elf_link_output_sym (finfo, name, isym, sec))
5808 return false;
5809 }
5810
5811 r_symndx = finfo->indices[r_symndx];
5812 }
5813
5814 irela->r_info = ELF_R_INFO (r_symndx,
5815 ELF_R_TYPE (irela->r_info));
5816 }
5817
5818 /* Swap out the relocs. */
5819 input_rel_hdr = &elf_section_data (o)->rel_hdr;
5820 elf_link_output_relocs (output_bfd, o,
5821 input_rel_hdr,
5822 internal_relocs);
5823 internal_relocs
5824 += input_rel_hdr->sh_size / input_rel_hdr->sh_entsize;
5825 input_rel_hdr = elf_section_data (o)->rel_hdr2;
5826 if (input_rel_hdr)
5827 elf_link_output_relocs (output_bfd, o,
5828 input_rel_hdr,
5829 internal_relocs);
5830 }
5831 }
5832
5833 /* Write out the modified section contents. */
5834 if (elf_section_data (o)->stab_info == NULL)
5835 {
5836 if (! (o->flags & SEC_EXCLUDE) &&
5837 ! bfd_set_section_contents (output_bfd, o->output_section,
5838 contents, o->output_offset,
5839 (o->_cooked_size != 0
5840 ? o->_cooked_size
5841 : o->_raw_size)))
5842 return false;
5843 }
5844 else
5845 {
5846 if (! (_bfd_write_section_stabs
5847 (output_bfd, &elf_hash_table (finfo->info)->stab_info,
5848 o, &elf_section_data (o)->stab_info, contents)))
5849 return false;
5850 }
5851 }
5852
5853 return true;
5854 }
5855
5856 /* Generate a reloc when linking an ELF file. This is a reloc
5857 requested by the linker, and does come from any input file. This
5858 is used to build constructor and destructor tables when linking
5859 with -Ur. */
5860
5861 static boolean
5862 elf_reloc_link_order (output_bfd, info, output_section, link_order)
5863 bfd *output_bfd;
5864 struct bfd_link_info *info;
5865 asection *output_section;
5866 struct bfd_link_order *link_order;
5867 {
5868 reloc_howto_type *howto;
5869 long indx;
5870 bfd_vma offset;
5871 bfd_vma addend;
5872 struct elf_link_hash_entry **rel_hash_ptr;
5873 Elf_Internal_Shdr *rel_hdr;
5874 struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
5875
5876 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
5877 if (howto == NULL)
5878 {
5879 bfd_set_error (bfd_error_bad_value);
5880 return false;
5881 }
5882
5883 addend = link_order->u.reloc.p->addend;
5884
5885 /* Figure out the symbol index. */
5886 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
5887 + elf_section_data (output_section)->rel_count
5888 + elf_section_data (output_section)->rel_count2);
5889 if (link_order->type == bfd_section_reloc_link_order)
5890 {
5891 indx = link_order->u.reloc.p->u.section->target_index;
5892 BFD_ASSERT (indx != 0);
5893 *rel_hash_ptr = NULL;
5894 }
5895 else
5896 {
5897 struct elf_link_hash_entry *h;
5898
5899 /* Treat a reloc against a defined symbol as though it were
5900 actually against the section. */
5901 h = ((struct elf_link_hash_entry *)
5902 bfd_wrapped_link_hash_lookup (output_bfd, info,
5903 link_order->u.reloc.p->u.name,
5904 false, false, true));
5905 if (h != NULL
5906 && (h->root.type == bfd_link_hash_defined
5907 || h->root.type == bfd_link_hash_defweak))
5908 {
5909 asection *section;
5910
5911 section = h->root.u.def.section;
5912 indx = section->output_section->target_index;
5913 *rel_hash_ptr = NULL;
5914 /* It seems that we ought to add the symbol value to the
5915 addend here, but in practice it has already been added
5916 because it was passed to constructor_callback. */
5917 addend += section->output_section->vma + section->output_offset;
5918 }
5919 else if (h != NULL)
5920 {
5921 /* Setting the index to -2 tells elf_link_output_extsym that
5922 this symbol is used by a reloc. */
5923 h->indx = -2;
5924 *rel_hash_ptr = h;
5925 indx = 0;
5926 }
5927 else
5928 {
5929 if (! ((*info->callbacks->unattached_reloc)
5930 (info, link_order->u.reloc.p->u.name, (bfd *) NULL,
5931 (asection *) NULL, (bfd_vma) 0)))
5932 return false;
5933 indx = 0;
5934 }
5935 }
5936
5937 /* If this is an inplace reloc, we must write the addend into the
5938 object file. */
5939 if (howto->partial_inplace && addend != 0)
5940 {
5941 bfd_size_type size;
5942 bfd_reloc_status_type rstat;
5943 bfd_byte *buf;
5944 boolean ok;
5945
5946 size = bfd_get_reloc_size (howto);
5947 buf = (bfd_byte *) bfd_zmalloc (size);
5948 if (buf == (bfd_byte *) NULL)
5949 return false;
5950 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
5951 switch (rstat)
5952 {
5953 case bfd_reloc_ok:
5954 break;
5955 default:
5956 case bfd_reloc_outofrange:
5957 abort ();
5958 case bfd_reloc_overflow:
5959 if (! ((*info->callbacks->reloc_overflow)
5960 (info,
5961 (link_order->type == bfd_section_reloc_link_order
5962 ? bfd_section_name (output_bfd,
5963 link_order->u.reloc.p->u.section)
5964 : link_order->u.reloc.p->u.name),
5965 howto->name, addend, (bfd *) NULL, (asection *) NULL,
5966 (bfd_vma) 0)))
5967 {
5968 free (buf);
5969 return false;
5970 }
5971 break;
5972 }
5973 ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf,
5974 (file_ptr) link_order->offset, size);
5975 free (buf);
5976 if (! ok)
5977 return false;
5978 }
5979
5980 /* The address of a reloc is relative to the section in a
5981 relocateable file, and is a virtual address in an executable
5982 file. */
5983 offset = link_order->offset;
5984 if (! info->relocateable)
5985 offset += output_section->vma;
5986
5987 rel_hdr = &elf_section_data (output_section)->rel_hdr;
5988
5989 if (rel_hdr->sh_type == SHT_REL)
5990 {
5991 Elf_Internal_Rel irel;
5992 Elf_External_Rel *erel;
5993
5994 irel.r_offset = offset;
5995 irel.r_info = ELF_R_INFO (indx, howto->type);
5996 erel = ((Elf_External_Rel *) rel_hdr->contents
5997 + elf_section_data (output_section)->rel_count);
5998 if (bed->s->swap_reloc_out)
5999 (*bed->s->swap_reloc_out) (output_bfd, &irel, (bfd_byte *) erel);
6000 else
6001 elf_swap_reloc_out (output_bfd, &irel, erel);
6002 }
6003 else
6004 {
6005 Elf_Internal_Rela irela;
6006 Elf_External_Rela *erela;
6007
6008 irela.r_offset = offset;
6009 irela.r_info = ELF_R_INFO (indx, howto->type);
6010 irela.r_addend = addend;
6011 erela = ((Elf_External_Rela *) rel_hdr->contents
6012 + elf_section_data (output_section)->rel_count);
6013 if (bed->s->swap_reloca_out)
6014 (*bed->s->swap_reloca_out) (output_bfd, &irela, (bfd_byte *) erela);
6015 else
6016 elf_swap_reloca_out (output_bfd, &irela, erela);
6017 }
6018
6019 ++elf_section_data (output_section)->rel_count;
6020
6021 return true;
6022 }
6023
6024 \f
6025 /* Allocate a pointer to live in a linker created section. */
6026
6027 boolean
6028 elf_create_pointer_linker_section (abfd, info, lsect, h, rel)
6029 bfd *abfd;
6030 struct bfd_link_info *info;
6031 elf_linker_section_t *lsect;
6032 struct elf_link_hash_entry *h;
6033 const Elf_Internal_Rela *rel;
6034 {
6035 elf_linker_section_pointers_t **ptr_linker_section_ptr = NULL;
6036 elf_linker_section_pointers_t *linker_section_ptr;
6037 unsigned long r_symndx = ELF_R_SYM (rel->r_info);;
6038
6039 BFD_ASSERT (lsect != NULL);
6040
6041 /* Is this a global symbol? */
6042 if (h != NULL)
6043 {
6044 /* Has this symbol already been allocated, if so, our work is done */
6045 if (_bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6046 rel->r_addend,
6047 lsect->which))
6048 return true;
6049
6050 ptr_linker_section_ptr = &h->linker_section_pointer;
6051 /* Make sure this symbol is output as a dynamic symbol. */
6052 if (h->dynindx == -1)
6053 {
6054 if (! elf_link_record_dynamic_symbol (info, h))
6055 return false;
6056 }
6057
6058 if (lsect->rel_section)
6059 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6060 }
6061
6062 else /* Allocation of a pointer to a local symbol */
6063 {
6064 elf_linker_section_pointers_t **ptr = elf_local_ptr_offsets (abfd);
6065
6066 /* Allocate a table to hold the local symbols if first time */
6067 if (!ptr)
6068 {
6069 unsigned int num_symbols = elf_tdata (abfd)->symtab_hdr.sh_info;
6070 register unsigned int i;
6071
6072 ptr = (elf_linker_section_pointers_t **)
6073 bfd_alloc (abfd, num_symbols * sizeof (elf_linker_section_pointers_t *));
6074
6075 if (!ptr)
6076 return false;
6077
6078 elf_local_ptr_offsets (abfd) = ptr;
6079 for (i = 0; i < num_symbols; i++)
6080 ptr[i] = (elf_linker_section_pointers_t *)0;
6081 }
6082
6083 /* Has this symbol already been allocated, if so, our work is done */
6084 if (_bfd_elf_find_pointer_linker_section (ptr[r_symndx],
6085 rel->r_addend,
6086 lsect->which))
6087 return true;
6088
6089 ptr_linker_section_ptr = &ptr[r_symndx];
6090
6091 if (info->shared)
6092 {
6093 /* If we are generating a shared object, we need to
6094 output a R_<xxx>_RELATIVE reloc so that the
6095 dynamic linker can adjust this GOT entry. */
6096 BFD_ASSERT (lsect->rel_section != NULL);
6097 lsect->rel_section->_raw_size += sizeof (Elf_External_Rela);
6098 }
6099 }
6100
6101 /* Allocate space for a pointer in the linker section, and allocate a new pointer record
6102 from internal memory. */
6103 BFD_ASSERT (ptr_linker_section_ptr != NULL);
6104 linker_section_ptr = (elf_linker_section_pointers_t *)
6105 bfd_alloc (abfd, sizeof (elf_linker_section_pointers_t));
6106
6107 if (!linker_section_ptr)
6108 return false;
6109
6110 linker_section_ptr->next = *ptr_linker_section_ptr;
6111 linker_section_ptr->addend = rel->r_addend;
6112 linker_section_ptr->which = lsect->which;
6113 linker_section_ptr->written_address_p = false;
6114 *ptr_linker_section_ptr = linker_section_ptr;
6115
6116 #if 0
6117 if (lsect->hole_size && lsect->hole_offset < lsect->max_hole_offset)
6118 {
6119 linker_section_ptr->offset = lsect->section->_raw_size - lsect->hole_size + (ARCH_SIZE / 8);
6120 lsect->hole_offset += ARCH_SIZE / 8;
6121 lsect->sym_offset += ARCH_SIZE / 8;
6122 if (lsect->sym_hash) /* Bump up symbol value if needed */
6123 {
6124 lsect->sym_hash->root.u.def.value += ARCH_SIZE / 8;
6125 #ifdef DEBUG
6126 fprintf (stderr, "Bump up %s by %ld, current value = %ld\n",
6127 lsect->sym_hash->root.root.string,
6128 (long)ARCH_SIZE / 8,
6129 (long)lsect->sym_hash->root.u.def.value);
6130 #endif
6131 }
6132 }
6133 else
6134 #endif
6135 linker_section_ptr->offset = lsect->section->_raw_size;
6136
6137 lsect->section->_raw_size += ARCH_SIZE / 8;
6138
6139 #ifdef DEBUG
6140 fprintf (stderr, "Create pointer in linker section %s, offset = %ld, section size = %ld\n",
6141 lsect->name, (long)linker_section_ptr->offset, (long)lsect->section->_raw_size);
6142 #endif
6143
6144 return true;
6145 }
6146
6147 \f
6148 #if ARCH_SIZE==64
6149 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_64 (BFD, VAL, ADDR)
6150 #endif
6151 #if ARCH_SIZE==32
6152 #define bfd_put_ptr(BFD,VAL,ADDR) bfd_put_32 (BFD, VAL, ADDR)
6153 #endif
6154
6155 /* Fill in the address for a pointer generated in alinker section. */
6156
6157 bfd_vma
6158 elf_finish_pointer_linker_section (output_bfd, input_bfd, info, lsect, h, relocation, rel, relative_reloc)
6159 bfd *output_bfd;
6160 bfd *input_bfd;
6161 struct bfd_link_info *info;
6162 elf_linker_section_t *lsect;
6163 struct elf_link_hash_entry *h;
6164 bfd_vma relocation;
6165 const Elf_Internal_Rela *rel;
6166 int relative_reloc;
6167 {
6168 elf_linker_section_pointers_t *linker_section_ptr;
6169
6170 BFD_ASSERT (lsect != NULL);
6171
6172 if (h != NULL) /* global symbol */
6173 {
6174 linker_section_ptr = _bfd_elf_find_pointer_linker_section (h->linker_section_pointer,
6175 rel->r_addend,
6176 lsect->which);
6177
6178 BFD_ASSERT (linker_section_ptr != NULL);
6179
6180 if (! elf_hash_table (info)->dynamic_sections_created
6181 || (info->shared
6182 && info->symbolic
6183 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
6184 {
6185 /* This is actually a static link, or it is a
6186 -Bsymbolic link and the symbol is defined
6187 locally. We must initialize this entry in the
6188 global section.
6189
6190 When doing a dynamic link, we create a .rela.<xxx>
6191 relocation entry to initialize the value. This
6192 is done in the finish_dynamic_symbol routine. */
6193 if (!linker_section_ptr->written_address_p)
6194 {
6195 linker_section_ptr->written_address_p = true;
6196 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6197 lsect->section->contents + linker_section_ptr->offset);
6198 }
6199 }
6200 }
6201 else /* local symbol */
6202 {
6203 unsigned long r_symndx = ELF_R_SYM (rel->r_info);
6204 BFD_ASSERT (elf_local_ptr_offsets (input_bfd) != NULL);
6205 BFD_ASSERT (elf_local_ptr_offsets (input_bfd)[r_symndx] != NULL);
6206 linker_section_ptr = _bfd_elf_find_pointer_linker_section (elf_local_ptr_offsets (input_bfd)[r_symndx],
6207 rel->r_addend,
6208 lsect->which);
6209
6210 BFD_ASSERT (linker_section_ptr != NULL);
6211
6212 /* Write out pointer if it hasn't been rewritten out before */
6213 if (!linker_section_ptr->written_address_p)
6214 {
6215 linker_section_ptr->written_address_p = true;
6216 bfd_put_ptr (output_bfd, relocation + linker_section_ptr->addend,
6217 lsect->section->contents + linker_section_ptr->offset);
6218
6219 if (info->shared)
6220 {
6221 asection *srel = lsect->rel_section;
6222 Elf_Internal_Rela outrel;
6223
6224 /* We need to generate a relative reloc for the dynamic linker. */
6225 if (!srel)
6226 lsect->rel_section = srel = bfd_get_section_by_name (elf_hash_table (info)->dynobj,
6227 lsect->rel_name);
6228
6229 BFD_ASSERT (srel != NULL);
6230
6231 outrel.r_offset = (lsect->section->output_section->vma
6232 + lsect->section->output_offset
6233 + linker_section_ptr->offset);
6234 outrel.r_info = ELF_R_INFO (0, relative_reloc);
6235 outrel.r_addend = 0;
6236 elf_swap_reloca_out (output_bfd, &outrel,
6237 (((Elf_External_Rela *)
6238 lsect->section->contents)
6239 + elf_section_data (lsect->section)->rel_count));
6240 ++elf_section_data (lsect->section)->rel_count;
6241 }
6242 }
6243 }
6244
6245 relocation = (lsect->section->output_offset
6246 + linker_section_ptr->offset
6247 - lsect->hole_offset
6248 - lsect->sym_offset);
6249
6250 #ifdef DEBUG
6251 fprintf (stderr, "Finish pointer in linker section %s, offset = %ld (0x%lx)\n",
6252 lsect->name, (long)relocation, (long)relocation);
6253 #endif
6254
6255 /* Subtract out the addend, because it will get added back in by the normal
6256 processing. */
6257 return relocation - linker_section_ptr->addend;
6258 }
6259 \f
6260 /* Garbage collect unused sections. */
6261
6262 static boolean elf_gc_mark
6263 PARAMS ((struct bfd_link_info *info, asection *sec,
6264 asection * (*gc_mark_hook)
6265 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6266 struct elf_link_hash_entry *, Elf_Internal_Sym *))));
6267
6268 static boolean elf_gc_sweep
6269 PARAMS ((struct bfd_link_info *info,
6270 boolean (*gc_sweep_hook)
6271 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6272 const Elf_Internal_Rela *relocs))));
6273
6274 static boolean elf_gc_sweep_symbol
6275 PARAMS ((struct elf_link_hash_entry *h, PTR idxptr));
6276
6277 static boolean elf_gc_allocate_got_offsets
6278 PARAMS ((struct elf_link_hash_entry *h, PTR offarg));
6279
6280 static boolean elf_gc_propagate_vtable_entries_used
6281 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6282
6283 static boolean elf_gc_smash_unused_vtentry_relocs
6284 PARAMS ((struct elf_link_hash_entry *h, PTR dummy));
6285
6286 /* The mark phase of garbage collection. For a given section, mark
6287 it, and all the sections which define symbols to which it refers. */
6288
6289 static boolean
6290 elf_gc_mark (info, sec, gc_mark_hook)
6291 struct bfd_link_info *info;
6292 asection *sec;
6293 asection * (*gc_mark_hook)
6294 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
6295 struct elf_link_hash_entry *, Elf_Internal_Sym *));
6296 {
6297 boolean ret = true;
6298
6299 sec->gc_mark = 1;
6300
6301 /* Look through the section relocs. */
6302
6303 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
6304 {
6305 Elf_Internal_Rela *relstart, *rel, *relend;
6306 Elf_Internal_Shdr *symtab_hdr;
6307 struct elf_link_hash_entry **sym_hashes;
6308 size_t nlocsyms;
6309 size_t extsymoff;
6310 Elf_External_Sym *locsyms, *freesyms = NULL;
6311 bfd *input_bfd = sec->owner;
6312 struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
6313
6314 /* GCFIXME: how to arrange so that relocs and symbols are not
6315 reread continually? */
6316
6317 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6318 sym_hashes = elf_sym_hashes (input_bfd);
6319
6320 /* Read the local symbols. */
6321 if (elf_bad_symtab (input_bfd))
6322 {
6323 nlocsyms = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6324 extsymoff = 0;
6325 }
6326 else
6327 extsymoff = nlocsyms = symtab_hdr->sh_info;
6328 if (symtab_hdr->contents)
6329 locsyms = (Elf_External_Sym *) symtab_hdr->contents;
6330 else if (nlocsyms == 0)
6331 locsyms = NULL;
6332 else
6333 {
6334 locsyms = freesyms =
6335 bfd_malloc (nlocsyms * sizeof (Elf_External_Sym));
6336 if (freesyms == NULL
6337 || bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0
6338 || (bfd_read (locsyms, sizeof (Elf_External_Sym),
6339 nlocsyms, input_bfd)
6340 != nlocsyms * sizeof (Elf_External_Sym)))
6341 {
6342 ret = false;
6343 goto out1;
6344 }
6345 }
6346
6347 /* Read the relocations. */
6348 relstart = (NAME(_bfd_elf,link_read_relocs)
6349 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL,
6350 info->keep_memory));
6351 if (relstart == NULL)
6352 {
6353 ret = false;
6354 goto out1;
6355 }
6356 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6357
6358 for (rel = relstart; rel < relend; rel++)
6359 {
6360 unsigned long r_symndx;
6361 asection *rsec;
6362 struct elf_link_hash_entry *h;
6363 Elf_Internal_Sym s;
6364
6365 r_symndx = ELF_R_SYM (rel->r_info);
6366 if (r_symndx == 0)
6367 continue;
6368
6369 if (elf_bad_symtab (sec->owner))
6370 {
6371 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6372 if (ELF_ST_BIND (s.st_info) == STB_LOCAL)
6373 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6374 else
6375 {
6376 h = sym_hashes[r_symndx - extsymoff];
6377 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6378 }
6379 }
6380 else if (r_symndx >= nlocsyms)
6381 {
6382 h = sym_hashes[r_symndx - extsymoff];
6383 rsec = (*gc_mark_hook)(sec->owner, info, rel, h, NULL);
6384 }
6385 else
6386 {
6387 elf_swap_symbol_in (input_bfd, &locsyms[r_symndx], &s);
6388 rsec = (*gc_mark_hook)(sec->owner, info, rel, NULL, &s);
6389 }
6390
6391 if (rsec && !rsec->gc_mark)
6392 if (!elf_gc_mark (info, rsec, gc_mark_hook))
6393 {
6394 ret = false;
6395 goto out2;
6396 }
6397 }
6398
6399 out2:
6400 if (!info->keep_memory)
6401 free (relstart);
6402 out1:
6403 if (freesyms)
6404 free (freesyms);
6405 }
6406
6407 return ret;
6408 }
6409
6410 /* The sweep phase of garbage collection. Remove all garbage sections. */
6411
6412 static boolean
6413 elf_gc_sweep (info, gc_sweep_hook)
6414 struct bfd_link_info *info;
6415 boolean (*gc_sweep_hook)
6416 PARAMS ((bfd *abfd, struct bfd_link_info *info, asection *o,
6417 const Elf_Internal_Rela *relocs));
6418 {
6419 bfd *sub;
6420
6421 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6422 {
6423 asection *o;
6424
6425 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6426 continue;
6427
6428 for (o = sub->sections; o != NULL; o = o->next)
6429 {
6430 /* Keep special sections. Keep .debug sections. */
6431 if ((o->flags & SEC_LINKER_CREATED)
6432 || (o->flags & SEC_DEBUGGING))
6433 o->gc_mark = 1;
6434
6435 if (o->gc_mark)
6436 continue;
6437
6438 /* Skip sweeping sections already excluded. */
6439 if (o->flags & SEC_EXCLUDE)
6440 continue;
6441
6442 /* Since this is early in the link process, it is simple
6443 to remove a section from the output. */
6444 o->flags |= SEC_EXCLUDE;
6445
6446 /* But we also have to update some of the relocation
6447 info we collected before. */
6448 if (gc_sweep_hook
6449 && (o->flags & SEC_RELOC) && o->reloc_count > 0)
6450 {
6451 Elf_Internal_Rela *internal_relocs;
6452 boolean r;
6453
6454 internal_relocs = (NAME(_bfd_elf,link_read_relocs)
6455 (o->owner, o, NULL, NULL, info->keep_memory));
6456 if (internal_relocs == NULL)
6457 return false;
6458
6459 r = (*gc_sweep_hook)(o->owner, info, o, internal_relocs);
6460
6461 if (!info->keep_memory)
6462 free (internal_relocs);
6463
6464 if (!r)
6465 return false;
6466 }
6467 }
6468 }
6469
6470 /* Remove the symbols that were in the swept sections from the dynamic
6471 symbol table. GCFIXME: Anyone know how to get them out of the
6472 static symbol table as well? */
6473 {
6474 int i = 0;
6475
6476 elf_link_hash_traverse (elf_hash_table (info),
6477 elf_gc_sweep_symbol,
6478 (PTR) &i);
6479
6480 elf_hash_table (info)->dynsymcount = i;
6481 }
6482
6483 return true;
6484 }
6485
6486 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
6487
6488 static boolean
6489 elf_gc_sweep_symbol (h, idxptr)
6490 struct elf_link_hash_entry *h;
6491 PTR idxptr;
6492 {
6493 int *idx = (int *) idxptr;
6494
6495 if (h->dynindx != -1
6496 && ((h->root.type != bfd_link_hash_defined
6497 && h->root.type != bfd_link_hash_defweak)
6498 || h->root.u.def.section->gc_mark))
6499 h->dynindx = (*idx)++;
6500
6501 return true;
6502 }
6503
6504 /* Propogate collected vtable information. This is called through
6505 elf_link_hash_traverse. */
6506
6507 static boolean
6508 elf_gc_propagate_vtable_entries_used (h, okp)
6509 struct elf_link_hash_entry *h;
6510 PTR okp;
6511 {
6512 /* Those that are not vtables. */
6513 if (h->vtable_parent == NULL)
6514 return true;
6515
6516 /* Those vtables that do not have parents, we cannot merge. */
6517 if (h->vtable_parent == (struct elf_link_hash_entry *) -1)
6518 return true;
6519
6520 /* If we've already been done, exit. */
6521 if (h->vtable_entries_used && h->vtable_entries_used[-1])
6522 return true;
6523
6524 /* Make sure the parent's table is up to date. */
6525 elf_gc_propagate_vtable_entries_used (h->vtable_parent, okp);
6526
6527 if (h->vtable_entries_used == NULL)
6528 {
6529 /* None of this table's entries were referenced. Re-use the
6530 parent's table. */
6531 h->vtable_entries_used = h->vtable_parent->vtable_entries_used;
6532 h->vtable_entries_size = h->vtable_parent->vtable_entries_size;
6533 }
6534 else
6535 {
6536 size_t n;
6537 boolean *cu, *pu;
6538
6539 /* Or the parent's entries into ours. */
6540 cu = h->vtable_entries_used;
6541 cu[-1] = true;
6542 pu = h->vtable_parent->vtable_entries_used;
6543 if (pu != NULL)
6544 {
6545 n = h->vtable_parent->vtable_entries_size / FILE_ALIGN;
6546 while (--n != 0)
6547 {
6548 if (*pu) *cu = true;
6549 pu++, cu++;
6550 }
6551 }
6552 }
6553
6554 return true;
6555 }
6556
6557 static boolean
6558 elf_gc_smash_unused_vtentry_relocs (h, okp)
6559 struct elf_link_hash_entry *h;
6560 PTR okp;
6561 {
6562 asection *sec;
6563 bfd_vma hstart, hend;
6564 Elf_Internal_Rela *relstart, *relend, *rel;
6565 struct elf_backend_data *bed;
6566
6567 /* Take care of both those symbols that do not describe vtables as
6568 well as those that are not loaded. */
6569 if (h->vtable_parent == NULL)
6570 return true;
6571
6572 BFD_ASSERT (h->root.type == bfd_link_hash_defined
6573 || h->root.type == bfd_link_hash_defweak);
6574
6575 sec = h->root.u.def.section;
6576 hstart = h->root.u.def.value;
6577 hend = hstart + h->size;
6578
6579 relstart = (NAME(_bfd_elf,link_read_relocs)
6580 (sec->owner, sec, NULL, (Elf_Internal_Rela *) NULL, true));
6581 if (!relstart)
6582 return *(boolean *)okp = false;
6583 bed = get_elf_backend_data (sec->owner);
6584 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
6585
6586 for (rel = relstart; rel < relend; ++rel)
6587 if (rel->r_offset >= hstart && rel->r_offset < hend)
6588 {
6589 /* If the entry is in use, do nothing. */
6590 if (h->vtable_entries_used
6591 && (rel->r_offset - hstart) < h->vtable_entries_size)
6592 {
6593 bfd_vma entry = (rel->r_offset - hstart) / FILE_ALIGN;
6594 if (h->vtable_entries_used[entry])
6595 continue;
6596 }
6597 /* Otherwise, kill it. */
6598 rel->r_offset = rel->r_info = rel->r_addend = 0;
6599 }
6600
6601 return true;
6602 }
6603
6604 /* Do mark and sweep of unused sections. */
6605
6606 boolean
6607 elf_gc_sections (abfd, info)
6608 bfd *abfd;
6609 struct bfd_link_info *info;
6610 {
6611 boolean ok = true;
6612 bfd *sub;
6613 asection * (*gc_mark_hook)
6614 PARAMS ((bfd *abfd, struct bfd_link_info *, Elf_Internal_Rela *,
6615 struct elf_link_hash_entry *h, Elf_Internal_Sym *));
6616
6617 if (!get_elf_backend_data (abfd)->can_gc_sections
6618 || info->relocateable || info->emitrelocations
6619 || elf_hash_table (info)->dynamic_sections_created)
6620 return true;
6621
6622 /* Apply transitive closure to the vtable entry usage info. */
6623 elf_link_hash_traverse (elf_hash_table (info),
6624 elf_gc_propagate_vtable_entries_used,
6625 (PTR) &ok);
6626 if (!ok)
6627 return false;
6628
6629 /* Kill the vtable relocations that were not used. */
6630 elf_link_hash_traverse (elf_hash_table (info),
6631 elf_gc_smash_unused_vtentry_relocs,
6632 (PTR) &ok);
6633 if (!ok)
6634 return false;
6635
6636 /* Grovel through relocs to find out who stays ... */
6637
6638 gc_mark_hook = get_elf_backend_data (abfd)->gc_mark_hook;
6639 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
6640 {
6641 asection *o;
6642
6643 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
6644 continue;
6645
6646 for (o = sub->sections; o != NULL; o = o->next)
6647 {
6648 if (o->flags & SEC_KEEP)
6649 if (!elf_gc_mark (info, o, gc_mark_hook))
6650 return false;
6651 }
6652 }
6653
6654 /* ... and mark SEC_EXCLUDE for those that go. */
6655 if (!elf_gc_sweep(info, get_elf_backend_data (abfd)->gc_sweep_hook))
6656 return false;
6657
6658 return true;
6659 }
6660 \f
6661 /* Called from check_relocs to record the existance of a VTINHERIT reloc. */
6662
6663 boolean
6664 elf_gc_record_vtinherit (abfd, sec, h, offset)
6665 bfd *abfd;
6666 asection *sec;
6667 struct elf_link_hash_entry *h;
6668 bfd_vma offset;
6669 {
6670 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
6671 struct elf_link_hash_entry **search, *child;
6672 bfd_size_type extsymcount;
6673
6674 /* The sh_info field of the symtab header tells us where the
6675 external symbols start. We don't care about the local symbols at
6676 this point. */
6677 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size/sizeof (Elf_External_Sym);
6678 if (!elf_bad_symtab (abfd))
6679 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
6680
6681 sym_hashes = elf_sym_hashes (abfd);
6682 sym_hashes_end = sym_hashes + extsymcount;
6683
6684 /* Hunt down the child symbol, which is in this section at the same
6685 offset as the relocation. */
6686 for (search = sym_hashes; search != sym_hashes_end; ++search)
6687 {
6688 if ((child = *search) != NULL
6689 && (child->root.type == bfd_link_hash_defined
6690 || child->root.type == bfd_link_hash_defweak)
6691 && child->root.u.def.section == sec
6692 && child->root.u.def.value == offset)
6693 goto win;
6694 }
6695
6696 (*_bfd_error_handler) ("%s: %s+%lu: No symbol found for INHERIT",
6697 bfd_get_filename (abfd), sec->name,
6698 (unsigned long)offset);
6699 bfd_set_error (bfd_error_invalid_operation);
6700 return false;
6701
6702 win:
6703 if (!h)
6704 {
6705 /* This *should* only be the absolute section. It could potentially
6706 be that someone has defined a non-global vtable though, which
6707 would be bad. It isn't worth paging in the local symbols to be
6708 sure though; that case should simply be handled by the assembler. */
6709
6710 child->vtable_parent = (struct elf_link_hash_entry *) -1;
6711 }
6712 else
6713 child->vtable_parent = h;
6714
6715 return true;
6716 }
6717
6718 /* Called from check_relocs to record the existance of a VTENTRY reloc. */
6719
6720 boolean
6721 elf_gc_record_vtentry (abfd, sec, h, addend)
6722 bfd *abfd ATTRIBUTE_UNUSED;
6723 asection *sec ATTRIBUTE_UNUSED;
6724 struct elf_link_hash_entry *h;
6725 bfd_vma addend;
6726 {
6727 if (addend >= h->vtable_entries_size)
6728 {
6729 size_t size, bytes;
6730 boolean *ptr = h->vtable_entries_used;
6731
6732 /* While the symbol is undefined, we have to be prepared to handle
6733 a zero size. */
6734 if (h->root.type == bfd_link_hash_undefined)
6735 size = addend;
6736 else
6737 {
6738 size = h->size;
6739 if (size < addend)
6740 {
6741 /* Oops! We've got a reference past the defined end of
6742 the table. This is probably a bug -- shall we warn? */
6743 size = addend;
6744 }
6745 }
6746
6747 /* Allocate one extra entry for use as a "done" flag for the
6748 consolidation pass. */
6749 bytes = (size / FILE_ALIGN + 1) * sizeof (boolean);
6750
6751 if (ptr)
6752 {
6753 ptr = bfd_realloc (ptr - 1, bytes);
6754
6755 if (ptr != NULL)
6756 {
6757 size_t oldbytes;
6758
6759 oldbytes = (h->vtable_entries_size/FILE_ALIGN + 1) * sizeof (boolean);
6760 memset (((char *)ptr) + oldbytes, 0, bytes - oldbytes);
6761 }
6762 }
6763 else
6764 ptr = bfd_zmalloc (bytes);
6765
6766 if (ptr == NULL)
6767 return false;
6768
6769 /* And arrange for that done flag to be at index -1. */
6770 h->vtable_entries_used = ptr + 1;
6771 h->vtable_entries_size = size;
6772 }
6773
6774 h->vtable_entries_used[addend / FILE_ALIGN] = true;
6775
6776 return true;
6777 }
6778
6779 /* And an accompanying bit to work out final got entry offsets once
6780 we're done. Should be called from final_link. */
6781
6782 boolean
6783 elf_gc_common_finalize_got_offsets (abfd, info)
6784 bfd *abfd;
6785 struct bfd_link_info *info;
6786 {
6787 bfd *i;
6788 struct elf_backend_data *bed = get_elf_backend_data (abfd);
6789 bfd_vma gotoff;
6790
6791 /* The GOT offset is relative to the .got section, but the GOT header is
6792 put into the .got.plt section, if the backend uses it. */
6793 if (bed->want_got_plt)
6794 gotoff = 0;
6795 else
6796 gotoff = bed->got_header_size;
6797
6798 /* Do the local .got entries first. */
6799 for (i = info->input_bfds; i; i = i->link_next)
6800 {
6801 bfd_signed_vma *local_got;
6802 bfd_size_type j, locsymcount;
6803 Elf_Internal_Shdr *symtab_hdr;
6804
6805 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
6806 continue;
6807
6808 local_got = elf_local_got_refcounts (i);
6809 if (!local_got)
6810 continue;
6811
6812 symtab_hdr = &elf_tdata (i)->symtab_hdr;
6813 if (elf_bad_symtab (i))
6814 locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym);
6815 else
6816 locsymcount = symtab_hdr->sh_info;
6817
6818 for (j = 0; j < locsymcount; ++j)
6819 {
6820 if (local_got[j] > 0)
6821 {
6822 local_got[j] = gotoff;
6823 gotoff += ARCH_SIZE / 8;
6824 }
6825 else
6826 local_got[j] = (bfd_vma) -1;
6827 }
6828 }
6829
6830 /* Then the global .got entries. .plt refcounts are handled by
6831 adjust_dynamic_symbol */
6832 elf_link_hash_traverse (elf_hash_table (info),
6833 elf_gc_allocate_got_offsets,
6834 (PTR) &gotoff);
6835 return true;
6836 }
6837
6838 /* We need a special top-level link routine to convert got reference counts
6839 to real got offsets. */
6840
6841 static boolean
6842 elf_gc_allocate_got_offsets (h, offarg)
6843 struct elf_link_hash_entry *h;
6844 PTR offarg;
6845 {
6846 bfd_vma *off = (bfd_vma *) offarg;
6847
6848 if (h->got.refcount > 0)
6849 {
6850 h->got.offset = off[0];
6851 off[0] += ARCH_SIZE / 8;
6852 }
6853 else
6854 h->got.offset = (bfd_vma) -1;
6855
6856 return true;
6857 }
6858
6859 /* Many folk need no more in the way of final link than this, once
6860 got entry reference counting is enabled. */
6861
6862 boolean
6863 elf_gc_common_final_link (abfd, info)
6864 bfd *abfd;
6865 struct bfd_link_info *info;
6866 {
6867 if (!elf_gc_common_finalize_got_offsets (abfd, info))
6868 return false;
6869
6870 /* Invoke the regular ELF backend linker to do all the work. */
6871 return elf_bfd_final_link (abfd, info);
6872 }
6873
6874 /* This function will be called though elf_link_hash_traverse to store
6875 all hash value of the exported symbols in an array. */
6876
6877 static boolean
6878 elf_collect_hash_codes (h, data)
6879 struct elf_link_hash_entry *h;
6880 PTR data;
6881 {
6882 unsigned long **valuep = (unsigned long **) data;
6883 const char *name;
6884 char *p;
6885 unsigned long ha;
6886 char *alc = NULL;
6887
6888 /* Ignore indirect symbols. These are added by the versioning code. */
6889 if (h->dynindx == -1)
6890 return true;
6891
6892 name = h->root.root.string;
6893 p = strchr (name, ELF_VER_CHR);
6894 if (p != NULL)
6895 {
6896 alc = bfd_malloc (p - name + 1);
6897 memcpy (alc, name, p - name);
6898 alc[p - name] = '\0';
6899 name = alc;
6900 }
6901
6902 /* Compute the hash value. */
6903 ha = bfd_elf_hash (name);
6904
6905 /* Store the found hash value in the array given as the argument. */
6906 *(*valuep)++ = ha;
6907
6908 /* And store it in the struct so that we can put it in the hash table
6909 later. */
6910 h->elf_hash_value = ha;
6911
6912 if (alc != NULL)
6913 free (alc);
6914
6915 return true;
6916 }
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