1 /* ELF linking support for BFD.
2    Copyright (C) 1995-2021 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 3 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., 51 Franklin Street - Fifth Floor, Boston,
19    MA 02110-1301, USA.  */
20 
21 #include "sysdep.h"
22 #include "bfd.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
29 #include "objalloc.h"
30 #if BFD_SUPPORTS_PLUGINS
31 #include "plugin-api.h"
32 #include "plugin.h"
33 #endif
34 
35 #include <limits.h>
36 #ifndef CHAR_BIT
37 #define CHAR_BIT 8
38 #endif
39 
40 /* This struct is used to pass information to routines called via
41    elf_link_hash_traverse which must return failure.  */
42 
43 struct elf_info_failed
44 {
45   struct bfd_link_info *info;
46   bool failed;
47 };
48 
49 /* This structure is used to pass information to
50    _bfd_elf_link_find_version_dependencies.  */
51 
52 struct elf_find_verdep_info
53 {
54   /* General link information.  */
55   struct bfd_link_info *info;
56   /* The number of dependencies.  */
57   unsigned int vers;
58   /* Whether we had a failure.  */
59   bool failed;
60 };
61 
62 static bool _bfd_elf_fix_symbol_flags
63   (struct elf_link_hash_entry *, struct elf_info_failed *);
64 
65 asection *
_bfd_elf_section_for_symbol(struct elf_reloc_cookie * cookie,unsigned long r_symndx,bool discard)66 _bfd_elf_section_for_symbol (struct elf_reloc_cookie *cookie,
67 			     unsigned long r_symndx,
68 			     bool discard)
69 {
70   if (r_symndx >= cookie->locsymcount
71       || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
72     {
73       struct elf_link_hash_entry *h;
74 
75       h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
76 
77       while (h->root.type == bfd_link_hash_indirect
78 	     || h->root.type == bfd_link_hash_warning)
79 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
80 
81       if ((h->root.type == bfd_link_hash_defined
82 	   || h->root.type == bfd_link_hash_defweak)
83 	   && discarded_section (h->root.u.def.section))
84 	return h->root.u.def.section;
85       else
86 	return NULL;
87     }
88   else
89     {
90       /* It's not a relocation against a global symbol,
91 	 but it could be a relocation against a local
92 	 symbol for a discarded section.  */
93       asection *isec;
94       Elf_Internal_Sym *isym;
95 
96       /* Need to: get the symbol; get the section.  */
97       isym = &cookie->locsyms[r_symndx];
98       isec = bfd_section_from_elf_index (cookie->abfd, isym->st_shndx);
99       if (isec != NULL
100 	  && discard ? discarded_section (isec) : 1)
101 	return isec;
102      }
103   return NULL;
104 }
105 
106 /* Define a symbol in a dynamic linkage section.  */
107 
108 struct elf_link_hash_entry *
_bfd_elf_define_linkage_sym(bfd * abfd,struct bfd_link_info * info,asection * sec,const char * name)109 _bfd_elf_define_linkage_sym (bfd *abfd,
110 			     struct bfd_link_info *info,
111 			     asection *sec,
112 			     const char *name)
113 {
114   struct elf_link_hash_entry *h;
115   struct bfd_link_hash_entry *bh;
116   const struct elf_backend_data *bed;
117 
118   h = elf_link_hash_lookup (elf_hash_table (info), name, false, false, false);
119   if (h != NULL)
120     {
121       /* Zap symbol defined in an as-needed lib that wasn't linked.
122 	 This is a symptom of a larger problem:  Absolute symbols
123 	 defined in shared libraries can't be overridden, because we
124 	 lose the link to the bfd which is via the symbol section.  */
125       h->root.type = bfd_link_hash_new;
126       bh = &h->root;
127     }
128   else
129     bh = NULL;
130 
131   bed = get_elf_backend_data (abfd);
132   if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
133 					 sec, 0, NULL, false, bed->collect,
134 					 &bh))
135     return NULL;
136   h = (struct elf_link_hash_entry *) bh;
137   BFD_ASSERT (h != NULL);
138   h->def_regular = 1;
139   h->non_elf = 0;
140   h->root.linker_def = 1;
141   h->type = STT_OBJECT;
142   if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
143     h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
144 
145   (*bed->elf_backend_hide_symbol) (info, h, true);
146   return h;
147 }
148 
149 bool
_bfd_elf_create_got_section(bfd * abfd,struct bfd_link_info * info)150 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
151 {
152   flagword flags;
153   asection *s;
154   struct elf_link_hash_entry *h;
155   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
156   struct elf_link_hash_table *htab = elf_hash_table (info);
157 
158   /* This function may be called more than once.  */
159   if (htab->sgot != NULL)
160     return true;
161 
162   flags = bed->dynamic_sec_flags;
163 
164   s = bfd_make_section_anyway_with_flags (abfd,
165 					  (bed->rela_plts_and_copies_p
166 					   ? ".rela.got" : ".rel.got"),
167 					  (bed->dynamic_sec_flags
168 					   | SEC_READONLY));
169   if (s == NULL
170       || !bfd_set_section_alignment (s, bed->s->log_file_align))
171     return false;
172   htab->srelgot = s;
173 
174   s = bfd_make_section_anyway_with_flags (abfd, ".got", flags);
175   if (s == NULL
176       || !bfd_set_section_alignment (s, bed->s->log_file_align))
177     return false;
178   htab->sgot = s;
179 
180   if (bed->want_got_plt)
181     {
182       s = bfd_make_section_anyway_with_flags (abfd, ".got.plt", flags);
183       if (s == NULL
184 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
185 	return false;
186       htab->sgotplt = s;
187     }
188 
189   /* The first bit of the global offset table is the header.  */
190   s->size += bed->got_header_size;
191 
192   if (bed->want_got_sym)
193     {
194       /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
195 	 (or .got.plt) section.  We don't do this in the linker script
196 	 because we don't want to define the symbol if we are not creating
197 	 a global offset table.  */
198       h = _bfd_elf_define_linkage_sym (abfd, info, s,
199 				       "_GLOBAL_OFFSET_TABLE_");
200       elf_hash_table (info)->hgot = h;
201       if (h == NULL)
202 	return false;
203     }
204 
205   return true;
206 }
207 
208 /* Create a strtab to hold the dynamic symbol names.  */
209 static bool
_bfd_elf_link_create_dynstrtab(bfd * abfd,struct bfd_link_info * info)210 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
211 {
212   struct elf_link_hash_table *hash_table;
213 
214   hash_table = elf_hash_table (info);
215   if (hash_table->dynobj == NULL)
216     {
217       /* We may not set dynobj, an input file holding linker created
218 	 dynamic sections to abfd, which may be a dynamic object with
219 	 its own dynamic sections.  We need to find a normal input file
220 	 to hold linker created sections if possible.  */
221       if ((abfd->flags & (DYNAMIC | BFD_PLUGIN)) != 0)
222 	{
223 	  bfd *ibfd;
224 	  asection *s;
225 	  for (ibfd = info->input_bfds; ibfd; ibfd = ibfd->link.next)
226 	    if ((ibfd->flags
227 		 & (DYNAMIC | BFD_LINKER_CREATED | BFD_PLUGIN)) == 0
228 		&& bfd_get_flavour (ibfd) == bfd_target_elf_flavour
229 		&& elf_object_id (ibfd) == elf_hash_table_id (hash_table)
230 		&& !((s = ibfd->sections) != NULL
231 		     && s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS))
232 	      {
233 		abfd = ibfd;
234 		break;
235 	      }
236 	}
237       hash_table->dynobj = abfd;
238     }
239 
240   if (hash_table->dynstr == NULL)
241     {
242       hash_table->dynstr = _bfd_elf_strtab_init ();
243       if (hash_table->dynstr == NULL)
244 	return false;
245     }
246   return true;
247 }
248 
249 /* Create some sections which will be filled in with dynamic linking
250    information.  ABFD is an input file which requires dynamic sections
251    to be created.  The dynamic sections take up virtual memory space
252    when the final executable is run, so we need to create them before
253    addresses are assigned to the output sections.  We work out the
254    actual contents and size of these sections later.  */
255 
256 bool
_bfd_elf_link_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)257 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
258 {
259   flagword flags;
260   asection *s;
261   const struct elf_backend_data *bed;
262   struct elf_link_hash_entry *h;
263 
264   if (! is_elf_hash_table (info->hash))
265     return false;
266 
267   if (elf_hash_table (info)->dynamic_sections_created)
268     return true;
269 
270   if (!_bfd_elf_link_create_dynstrtab (abfd, info))
271     return false;
272 
273   abfd = elf_hash_table (info)->dynobj;
274   bed = get_elf_backend_data (abfd);
275 
276   flags = bed->dynamic_sec_flags;
277 
278   /* A dynamically linked executable has a .interp section, but a
279      shared library does not.  */
280   if (bfd_link_executable (info) && !info->nointerp)
281     {
282       s = bfd_make_section_anyway_with_flags (abfd, ".interp",
283 					      flags | SEC_READONLY);
284       if (s == NULL)
285 	return false;
286     }
287 
288   /* Create sections to hold version informations.  These are removed
289      if they are not needed.  */
290   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version_d",
291 					  flags | SEC_READONLY);
292   if (s == NULL
293       || !bfd_set_section_alignment (s, bed->s->log_file_align))
294     return false;
295 
296   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version",
297 					  flags | SEC_READONLY);
298   if (s == NULL
299       || !bfd_set_section_alignment (s, 1))
300     return false;
301 
302   s = bfd_make_section_anyway_with_flags (abfd, ".gnu.version_r",
303 					  flags | SEC_READONLY);
304   if (s == NULL
305       || !bfd_set_section_alignment (s, bed->s->log_file_align))
306     return false;
307 
308   s = bfd_make_section_anyway_with_flags (abfd, ".dynsym",
309 					  flags | SEC_READONLY);
310   if (s == NULL
311       || !bfd_set_section_alignment (s, bed->s->log_file_align))
312     return false;
313   elf_hash_table (info)->dynsym = s;
314 
315   s = bfd_make_section_anyway_with_flags (abfd, ".dynstr",
316 					  flags | SEC_READONLY);
317   if (s == NULL)
318     return false;
319 
320   s = bfd_make_section_anyway_with_flags (abfd, ".dynamic", flags);
321   if (s == NULL
322       || !bfd_set_section_alignment (s, bed->s->log_file_align))
323     return false;
324 
325   /* The special symbol _DYNAMIC is always set to the start of the
326      .dynamic section.  We could set _DYNAMIC in a linker script, but we
327      only want to define it if we are, in fact, creating a .dynamic
328      section.  We don't want to define it if there is no .dynamic
329      section, since on some ELF platforms the start up code examines it
330      to decide how to initialize the process.  */
331   h = _bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC");
332   elf_hash_table (info)->hdynamic = h;
333   if (h == NULL)
334     return false;
335 
336   if (info->emit_hash)
337     {
338       s = bfd_make_section_anyway_with_flags (abfd, ".hash",
339 					      flags | SEC_READONLY);
340       if (s == NULL
341 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
342 	return false;
343       elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
344     }
345 
346   if (info->emit_gnu_hash && bed->record_xhash_symbol == NULL)
347     {
348       s = bfd_make_section_anyway_with_flags (abfd, ".gnu.hash",
349 					      flags | SEC_READONLY);
350       if (s == NULL
351 	  || !bfd_set_section_alignment (s, bed->s->log_file_align))
352 	return false;
353       /* For 64-bit ELF, .gnu.hash is a non-uniform entity size section:
354 	 4 32-bit words followed by variable count of 64-bit words, then
355 	 variable count of 32-bit words.  */
356       if (bed->s->arch_size == 64)
357 	elf_section_data (s)->this_hdr.sh_entsize = 0;
358       else
359 	elf_section_data (s)->this_hdr.sh_entsize = 4;
360     }
361 
362   /* Let the backend create the rest of the sections.  This lets the
363      backend set the right flags.  The backend will normally create
364      the .got and .plt sections.  */
365   if (bed->elf_backend_create_dynamic_sections == NULL
366       || ! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
367     return false;
368 
369   elf_hash_table (info)->dynamic_sections_created = true;
370 
371   return true;
372 }
373 
374 /* Create dynamic sections when linking against a dynamic object.  */
375 
376 bool
_bfd_elf_create_dynamic_sections(bfd * abfd,struct bfd_link_info * info)377 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
378 {
379   flagword flags, pltflags;
380   struct elf_link_hash_entry *h;
381   asection *s;
382   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
383   struct elf_link_hash_table *htab = elf_hash_table (info);
384 
385   /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
386      .rel[a].bss sections.  */
387   flags = bed->dynamic_sec_flags;
388 
389   pltflags = flags;
390   if (bed->plt_not_loaded)
391     /* We do not clear SEC_ALLOC here because we still want the OS to
392        allocate space for the section; it's just that there's nothing
393        to read in from the object file.  */
394     pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
395   else
396     pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
397   if (bed->plt_readonly)
398     pltflags |= SEC_READONLY;
399 
400   s = bfd_make_section_anyway_with_flags (abfd, ".plt", pltflags);
401   if (s == NULL
402       || !bfd_set_section_alignment (s, bed->plt_alignment))
403     return false;
404   htab->splt = s;
405 
406   /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
407      .plt section.  */
408   if (bed->want_plt_sym)
409     {
410       h = _bfd_elf_define_linkage_sym (abfd, info, s,
411 				       "_PROCEDURE_LINKAGE_TABLE_");
412       elf_hash_table (info)->hplt = h;
413       if (h == NULL)
414 	return false;
415     }
416 
417   s = bfd_make_section_anyway_with_flags (abfd,
418 					  (bed->rela_plts_and_copies_p
419 					   ? ".rela.plt" : ".rel.plt"),
420 					  flags | SEC_READONLY);
421   if (s == NULL
422       || !bfd_set_section_alignment (s, bed->s->log_file_align))
423     return false;
424   htab->srelplt = s;
425 
426   if (! _bfd_elf_create_got_section (abfd, info))
427     return false;
428 
429   if (bed->want_dynbss)
430     {
431       /* The .dynbss section is a place to put symbols which are defined
432 	 by dynamic objects, are referenced by regular objects, and are
433 	 not functions.  We must allocate space for them in the process
434 	 image and use a R_*_COPY reloc to tell the dynamic linker to
435 	 initialize them at run time.  The linker script puts the .dynbss
436 	 section into the .bss section of the final image.  */
437       s = bfd_make_section_anyway_with_flags (abfd, ".dynbss",
438 					      SEC_ALLOC | SEC_LINKER_CREATED);
439       if (s == NULL)
440 	return false;
441       htab->sdynbss = s;
442 
443       if (bed->want_dynrelro)
444 	{
445 	  /* Similarly, but for symbols that were originally in read-only
446 	     sections.  This section doesn't really need to have contents,
447 	     but make it like other .data.rel.ro sections.  */
448 	  s = bfd_make_section_anyway_with_flags (abfd, ".data.rel.ro",
449 						  flags);
450 	  if (s == NULL)
451 	    return false;
452 	  htab->sdynrelro = s;
453 	}
454 
455       /* The .rel[a].bss section holds copy relocs.  This section is not
456 	 normally needed.  We need to create it here, though, so that the
457 	 linker will map it to an output section.  We can't just create it
458 	 only if we need it, because we will not know whether we need it
459 	 until we have seen all the input files, and the first time the
460 	 main linker code calls BFD after examining all the input files
461 	 (size_dynamic_sections) the input sections have already been
462 	 mapped to the output sections.  If the section turns out not to
463 	 be needed, we can discard it later.  We will never need this
464 	 section when generating a shared object, since they do not use
465 	 copy relocs.  */
466       if (bfd_link_executable (info))
467 	{
468 	  s = bfd_make_section_anyway_with_flags (abfd,
469 						  (bed->rela_plts_and_copies_p
470 						   ? ".rela.bss" : ".rel.bss"),
471 						  flags | SEC_READONLY);
472 	  if (s == NULL
473 	      || !bfd_set_section_alignment (s, bed->s->log_file_align))
474 	    return false;
475 	  htab->srelbss = s;
476 
477 	  if (bed->want_dynrelro)
478 	    {
479 	      s = (bfd_make_section_anyway_with_flags
480 		   (abfd, (bed->rela_plts_and_copies_p
481 			   ? ".rela.data.rel.ro" : ".rel.data.rel.ro"),
482 		    flags | SEC_READONLY));
483 	      if (s == NULL
484 		  || !bfd_set_section_alignment (s, bed->s->log_file_align))
485 		return false;
486 	      htab->sreldynrelro = s;
487 	    }
488 	}
489     }
490 
491   return true;
492 }
493 
494 /* Record a new dynamic symbol.  We record the dynamic symbols as we
495    read the input files, since we need to have a list of all of them
496    before we can determine the final sizes of the output sections.
497    Note that we may actually call this function even though we are not
498    going to output any dynamic symbols; in some cases we know that a
499    symbol should be in the dynamic symbol table, but only if there is
500    one.  */
501 
502 bool
bfd_elf_link_record_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)503 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
504 				    struct elf_link_hash_entry *h)
505 {
506   if (h->dynindx == -1)
507     {
508       struct elf_strtab_hash *dynstr;
509       char *p;
510       const char *name;
511       size_t indx;
512 
513       if (h->root.type == bfd_link_hash_defined
514 	  || h->root.type == bfd_link_hash_defweak)
515 	{
516 	  /* An IR symbol should not be made dynamic.  */
517 	  if (h->root.u.def.section != NULL
518 	      && h->root.u.def.section->owner != NULL
519 	      && (h->root.u.def.section->owner->flags & BFD_PLUGIN) != 0)
520 	    return true;
521 	}
522 
523       /* XXX: The ABI draft says the linker must turn hidden and
524 	 internal symbols into STB_LOCAL symbols when producing the
525 	 DSO. However, if ld.so honors st_other in the dynamic table,
526 	 this would not be necessary.  */
527       switch (ELF_ST_VISIBILITY (h->other))
528 	{
529 	case STV_INTERNAL:
530 	case STV_HIDDEN:
531 	  if (h->root.type != bfd_link_hash_undefined
532 	      && h->root.type != bfd_link_hash_undefweak)
533 	    {
534 	      h->forced_local = 1;
535 	      if (!elf_hash_table (info)->is_relocatable_executable
536 		  || ((h->root.type == bfd_link_hash_defined
537 		       || h->root.type == bfd_link_hash_defweak)
538 		      && h->root.u.def.section->owner != NULL
539 		      && h->root.u.def.section->owner->no_export)
540 		  || (h->root.type == bfd_link_hash_common
541 		      && h->root.u.c.p->section->owner != NULL
542 		      && h->root.u.c.p->section->owner->no_export))
543 		return true;
544 	    }
545 
546 	default:
547 	  break;
548 	}
549 
550       h->dynindx = elf_hash_table (info)->dynsymcount;
551       ++elf_hash_table (info)->dynsymcount;
552 
553       dynstr = elf_hash_table (info)->dynstr;
554       if (dynstr == NULL)
555 	{
556 	  /* Create a strtab to hold the dynamic symbol names.  */
557 	  elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
558 	  if (dynstr == NULL)
559 	    return false;
560 	}
561 
562       /* We don't put any version information in the dynamic string
563 	 table.  */
564       name = h->root.root.string;
565       p = strchr (name, ELF_VER_CHR);
566       if (p != NULL)
567 	/* We know that the p points into writable memory.  In fact,
568 	   there are only a few symbols that have read-only names, being
569 	   those like _GLOBAL_OFFSET_TABLE_ that are created specially
570 	   by the backends.  Most symbols will have names pointing into
571 	   an ELF string table read from a file, or to objalloc memory.  */
572 	*p = 0;
573 
574       indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
575 
576       if (p != NULL)
577 	*p = ELF_VER_CHR;
578 
579       if (indx == (size_t) -1)
580 	return false;
581       h->dynstr_index = indx;
582     }
583 
584   return true;
585 }
586 
587 /* Mark a symbol dynamic.  */
588 
589 static void
bfd_elf_link_mark_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)590 bfd_elf_link_mark_dynamic_symbol (struct bfd_link_info *info,
591 				  struct elf_link_hash_entry *h,
592 				  Elf_Internal_Sym *sym)
593 {
594   struct bfd_elf_dynamic_list *d = info->dynamic_list;
595 
596   /* It may be called more than once on the same H.  */
597   if(h->dynamic || bfd_link_relocatable (info))
598     return;
599 
600   if ((info->dynamic_data
601        && (h->type == STT_OBJECT
602 	   || h->type == STT_COMMON
603 	   || (sym != NULL
604 	       && (ELF_ST_TYPE (sym->st_info) == STT_OBJECT
605 		   || ELF_ST_TYPE (sym->st_info) == STT_COMMON))))
606       || (d != NULL
607 	  && h->non_elf
608 	  && (*d->match) (&d->head, NULL, h->root.root.string)))
609     {
610       h->dynamic = 1;
611       /* NB: If a symbol is made dynamic by --dynamic-list, it has
612 	 non-IR reference.  */
613       h->root.non_ir_ref_dynamic = 1;
614     }
615 }
616 
617 /* Record an assignment to a symbol made by a linker script.  We need
618    this in case some dynamic object refers to this symbol.  */
619 
620 bool
bfd_elf_record_link_assignment(bfd * output_bfd,struct bfd_link_info * info,const char * name,bool provide,bool hidden)621 bfd_elf_record_link_assignment (bfd *output_bfd,
622 				struct bfd_link_info *info,
623 				const char *name,
624 				bool provide,
625 				bool hidden)
626 {
627   struct elf_link_hash_entry *h, *hv;
628   struct elf_link_hash_table *htab;
629   const struct elf_backend_data *bed;
630 
631   if (!is_elf_hash_table (info->hash))
632     return true;
633 
634   htab = elf_hash_table (info);
635   h = elf_link_hash_lookup (htab, name, !provide, true, false);
636   if (h == NULL)
637     return provide;
638 
639   if (h->root.type == bfd_link_hash_warning)
640     h = (struct elf_link_hash_entry *) h->root.u.i.link;
641 
642   if (h->versioned == unknown)
643     {
644       /* Set versioned if symbol version is unknown.  */
645       char *version = strrchr (name, ELF_VER_CHR);
646       if (version)
647 	{
648 	  if (version > name && version[-1] != ELF_VER_CHR)
649 	    h->versioned = versioned_hidden;
650 	  else
651 	    h->versioned = versioned;
652 	}
653     }
654 
655   /* Symbols defined in a linker script but not referenced anywhere
656      else will have non_elf set.  */
657   if (h->non_elf)
658     {
659       bfd_elf_link_mark_dynamic_symbol (info, h, NULL);
660       h->non_elf = 0;
661     }
662 
663   switch (h->root.type)
664     {
665     case bfd_link_hash_defined:
666     case bfd_link_hash_defweak:
667     case bfd_link_hash_common:
668       break;
669     case bfd_link_hash_undefweak:
670     case bfd_link_hash_undefined:
671       /* Since we're defining the symbol, don't let it seem to have not
672 	 been defined.  record_dynamic_symbol and size_dynamic_sections
673 	 may depend on this.  */
674       h->root.type = bfd_link_hash_new;
675       if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
676 	bfd_link_repair_undef_list (&htab->root);
677       break;
678     case bfd_link_hash_new:
679       break;
680     case bfd_link_hash_indirect:
681       /* We had a versioned symbol in a dynamic library.  We make the
682 	 the versioned symbol point to this one.  */
683       bed = get_elf_backend_data (output_bfd);
684       hv = h;
685       while (hv->root.type == bfd_link_hash_indirect
686 	     || hv->root.type == bfd_link_hash_warning)
687 	hv = (struct elf_link_hash_entry *) hv->root.u.i.link;
688       /* We don't need to update h->root.u since linker will set them
689 	 later.  */
690       h->root.type = bfd_link_hash_undefined;
691       hv->root.type = bfd_link_hash_indirect;
692       hv->root.u.i.link = (struct bfd_link_hash_entry *) h;
693       (*bed->elf_backend_copy_indirect_symbol) (info, h, hv);
694       break;
695     default:
696       BFD_FAIL ();
697       return false;
698     }
699 
700   /* If this symbol is being provided by the linker script, and it is
701      currently defined by a dynamic object, but not by a regular
702      object, then mark it as undefined so that the generic linker will
703      force the correct value.  */
704   if (provide
705       && h->def_dynamic
706       && !h->def_regular)
707     h->root.type = bfd_link_hash_undefined;
708 
709   /* If this symbol is currently defined by a dynamic object, but not
710      by a regular object, then clear out any version information because
711      the symbol will not be associated with the dynamic object any
712      more.  */
713   if (h->def_dynamic && !h->def_regular)
714     h->verinfo.verdef = NULL;
715 
716   /* Make sure this symbol is not garbage collected.  */
717   h->mark = 1;
718 
719   h->def_regular = 1;
720 
721   if (hidden)
722     {
723       bed = get_elf_backend_data (output_bfd);
724       if (ELF_ST_VISIBILITY (h->other) != STV_INTERNAL)
725 	h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
726       (*bed->elf_backend_hide_symbol) (info, h, true);
727     }
728 
729   /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
730      and executables.  */
731   if (!bfd_link_relocatable (info)
732       && h->dynindx != -1
733       && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
734 	  || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
735     h->forced_local = 1;
736 
737   if ((h->def_dynamic
738        || h->ref_dynamic
739        || bfd_link_dll (info)
740        || elf_hash_table (info)->is_relocatable_executable)
741       && !h->forced_local
742       && h->dynindx == -1)
743     {
744       if (! bfd_elf_link_record_dynamic_symbol (info, h))
745 	return false;
746 
747       /* If this is a weak defined symbol, and we know a corresponding
748 	 real symbol from the same dynamic object, make sure the real
749 	 symbol is also made into a dynamic symbol.  */
750       if (h->is_weakalias)
751 	{
752 	  struct elf_link_hash_entry *def = weakdef (h);
753 
754 	  if (def->dynindx == -1
755 	      && !bfd_elf_link_record_dynamic_symbol (info, def))
756 	    return false;
757 	}
758     }
759 
760   return true;
761 }
762 
763 /* Record a new local dynamic symbol.  Returns 0 on failure, 1 on
764    success, and 2 on a failure caused by attempting to record a symbol
765    in a discarded section, eg. a discarded link-once section symbol.  */
766 
767 int
bfd_elf_link_record_local_dynamic_symbol(struct bfd_link_info * info,bfd * input_bfd,long input_indx)768 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
769 					  bfd *input_bfd,
770 					  long input_indx)
771 {
772   size_t amt;
773   struct elf_link_local_dynamic_entry *entry;
774   struct elf_link_hash_table *eht;
775   struct elf_strtab_hash *dynstr;
776   size_t dynstr_index;
777   char *name;
778   Elf_External_Sym_Shndx eshndx;
779   char esym[sizeof (Elf64_External_Sym)];
780 
781   if (! is_elf_hash_table (info->hash))
782     return 0;
783 
784   /* See if the entry exists already.  */
785   for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
786     if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
787       return 1;
788 
789   amt = sizeof (*entry);
790   entry = (struct elf_link_local_dynamic_entry *) bfd_alloc (input_bfd, amt);
791   if (entry == NULL)
792     return 0;
793 
794   /* Go find the symbol, so that we can find it's name.  */
795   if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
796 			     1, input_indx, &entry->isym, esym, &eshndx))
797     {
798       bfd_release (input_bfd, entry);
799       return 0;
800     }
801 
802   if (entry->isym.st_shndx != SHN_UNDEF
803       && entry->isym.st_shndx < SHN_LORESERVE)
804     {
805       asection *s;
806 
807       s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
808       if (s == NULL || bfd_is_abs_section (s->output_section))
809 	{
810 	  /* We can still bfd_release here as nothing has done another
811 	     bfd_alloc.  We can't do this later in this function.  */
812 	  bfd_release (input_bfd, entry);
813 	  return 2;
814 	}
815     }
816 
817   name = (bfd_elf_string_from_elf_section
818 	  (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
819 	   entry->isym.st_name));
820 
821   dynstr = elf_hash_table (info)->dynstr;
822   if (dynstr == NULL)
823     {
824       /* Create a strtab to hold the dynamic symbol names.  */
825       elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
826       if (dynstr == NULL)
827 	return 0;
828     }
829 
830   dynstr_index = _bfd_elf_strtab_add (dynstr, name, false);
831   if (dynstr_index == (size_t) -1)
832     return 0;
833   entry->isym.st_name = dynstr_index;
834 
835   eht = elf_hash_table (info);
836 
837   entry->next = eht->dynlocal;
838   eht->dynlocal = entry;
839   entry->input_bfd = input_bfd;
840   entry->input_indx = input_indx;
841   eht->dynsymcount++;
842 
843   /* Whatever binding the symbol had before, it's now local.  */
844   entry->isym.st_info
845     = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
846 
847   /* The dynindx will be set at the end of size_dynamic_sections.  */
848 
849   return 1;
850 }
851 
852 /* Return the dynindex of a local dynamic symbol.  */
853 
854 long
_bfd_elf_link_lookup_local_dynindx(struct bfd_link_info * info,bfd * input_bfd,long input_indx)855 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
856 				    bfd *input_bfd,
857 				    long input_indx)
858 {
859   struct elf_link_local_dynamic_entry *e;
860 
861   for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
862     if (e->input_bfd == input_bfd && e->input_indx == input_indx)
863       return e->dynindx;
864   return -1;
865 }
866 
867 /* This function is used to renumber the dynamic symbols, if some of
868    them are removed because they are marked as local.  This is called
869    via elf_link_hash_traverse.  */
870 
871 static bool
elf_link_renumber_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)872 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
873 				      void *data)
874 {
875   size_t *count = (size_t *) data;
876 
877   if (h->forced_local)
878     return true;
879 
880   if (h->dynindx != -1)
881     h->dynindx = ++(*count);
882 
883   return true;
884 }
885 
886 
887 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
888    STB_LOCAL binding.  */
889 
890 static bool
elf_link_renumber_local_hash_table_dynsyms(struct elf_link_hash_entry * h,void * data)891 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
892 					    void *data)
893 {
894   size_t *count = (size_t *) data;
895 
896   if (!h->forced_local)
897     return true;
898 
899   if (h->dynindx != -1)
900     h->dynindx = ++(*count);
901 
902   return true;
903 }
904 
905 /* Return true if the dynamic symbol for a given section should be
906    omitted when creating a shared library.  */
907 bool
_bfd_elf_omit_section_dynsym_default(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info,asection * p)908 _bfd_elf_omit_section_dynsym_default (bfd *output_bfd ATTRIBUTE_UNUSED,
909 				      struct bfd_link_info *info,
910 				      asection *p)
911 {
912   struct elf_link_hash_table *htab;
913   asection *ip;
914 
915   switch (elf_section_data (p)->this_hdr.sh_type)
916     {
917     case SHT_PROGBITS:
918     case SHT_NOBITS:
919       /* If sh_type is yet undecided, assume it could be
920 	 SHT_PROGBITS/SHT_NOBITS.  */
921     case SHT_NULL:
922       htab = elf_hash_table (info);
923       if (htab->text_index_section != NULL)
924 	return p != htab->text_index_section && p != htab->data_index_section;
925 
926       return (htab->dynobj != NULL
927 	      && (ip = bfd_get_linker_section (htab->dynobj, p->name)) != NULL
928 	      && ip->output_section == p);
929 
930       /* There shouldn't be section relative relocations
931 	 against any other section.  */
932     default:
933       return true;
934     }
935 }
936 
937 bool
_bfd_elf_omit_section_dynsym_all(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,asection * p ATTRIBUTE_UNUSED)938 _bfd_elf_omit_section_dynsym_all
939     (bfd *output_bfd ATTRIBUTE_UNUSED,
940      struct bfd_link_info *info ATTRIBUTE_UNUSED,
941      asection *p ATTRIBUTE_UNUSED)
942 {
943   return true;
944 }
945 
946 /* Assign dynsym indices.  In a shared library we generate a section
947    symbol for each output section, which come first.  Next come symbols
948    which have been forced to local binding.  Then all of the back-end
949    allocated local dynamic syms, followed by the rest of the global
950    symbols.  If SECTION_SYM_COUNT is NULL, section dynindx is not set.
951    (This prevents the early call before elf_backend_init_index_section
952    and strip_excluded_output_sections setting dynindx for sections
953    that are stripped.)  */
954 
955 static unsigned long
_bfd_elf_link_renumber_dynsyms(bfd * output_bfd,struct bfd_link_info * info,unsigned long * section_sym_count)956 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
957 				struct bfd_link_info *info,
958 				unsigned long *section_sym_count)
959 {
960   unsigned long dynsymcount = 0;
961   bool do_sec = section_sym_count != NULL;
962 
963   if (bfd_link_pic (info)
964       || elf_hash_table (info)->is_relocatable_executable)
965     {
966       const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
967       asection *p;
968       for (p = output_bfd->sections; p ; p = p->next)
969 	if ((p->flags & SEC_EXCLUDE) == 0
970 	    && (p->flags & SEC_ALLOC) != 0
971 	    && elf_hash_table (info)->dynamic_relocs
972 	    && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
973 	  {
974 	    ++dynsymcount;
975 	    if (do_sec)
976 	      elf_section_data (p)->dynindx = dynsymcount;
977 	  }
978 	else if (do_sec)
979 	  elf_section_data (p)->dynindx = 0;
980     }
981   if (do_sec)
982     *section_sym_count = dynsymcount;
983 
984   elf_link_hash_traverse (elf_hash_table (info),
985 			  elf_link_renumber_local_hash_table_dynsyms,
986 			  &dynsymcount);
987 
988   if (elf_hash_table (info)->dynlocal)
989     {
990       struct elf_link_local_dynamic_entry *p;
991       for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
992 	p->dynindx = ++dynsymcount;
993     }
994   elf_hash_table (info)->local_dynsymcount = dynsymcount;
995 
996   elf_link_hash_traverse (elf_hash_table (info),
997 			  elf_link_renumber_hash_table_dynsyms,
998 			  &dynsymcount);
999 
1000   /* There is an unused NULL entry at the head of the table which we
1001      must account for in our count even if the table is empty since it
1002      is intended for the mandatory DT_SYMTAB tag (.dynsym section) in
1003      .dynamic section.  */
1004   dynsymcount++;
1005 
1006   elf_hash_table (info)->dynsymcount = dynsymcount;
1007   return dynsymcount;
1008 }
1009 
1010 /* Merge st_other field.  */
1011 
1012 static void
elf_merge_st_other(bfd * abfd,struct elf_link_hash_entry * h,unsigned int st_other,asection * sec,bool definition,bool dynamic)1013 elf_merge_st_other (bfd *abfd, struct elf_link_hash_entry *h,
1014 		    unsigned int st_other, asection *sec,
1015 		    bool definition, bool dynamic)
1016 {
1017   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1018 
1019   /* If st_other has a processor-specific meaning, specific
1020      code might be needed here.  */
1021   if (bed->elf_backend_merge_symbol_attribute)
1022     (*bed->elf_backend_merge_symbol_attribute) (h, st_other, definition,
1023 						dynamic);
1024 
1025   if (!dynamic)
1026     {
1027       unsigned symvis = ELF_ST_VISIBILITY (st_other);
1028       unsigned hvis = ELF_ST_VISIBILITY (h->other);
1029 
1030       /* Keep the most constraining visibility.  Leave the remainder
1031 	 of the st_other field to elf_backend_merge_symbol_attribute.  */
1032       if (symvis - 1 < hvis - 1)
1033 	h->other = symvis | (h->other & ~ELF_ST_VISIBILITY (-1));
1034     }
1035   else if (definition
1036 	   && ELF_ST_VISIBILITY (st_other) != STV_DEFAULT
1037 	   && (sec->flags & SEC_READONLY) == 0)
1038     h->protected_def = 1;
1039 }
1040 
1041 /* This function is called when we want to merge a new symbol with an
1042    existing symbol.  It handles the various cases which arise when we
1043    find a definition in a dynamic object, or when there is already a
1044    definition in a dynamic object.  The new symbol is described by
1045    NAME, SYM, PSEC, and PVALUE.  We set SYM_HASH to the hash table
1046    entry.  We set POLDBFD to the old symbol's BFD.  We set POLD_WEAK
1047    if the old symbol was weak.  We set POLD_ALIGNMENT to the alignment
1048    of an old common symbol.  We set OVERRIDE if the old symbol is
1049    overriding a new definition.  We set TYPE_CHANGE_OK if it is OK for
1050    the type to change.  We set SIZE_CHANGE_OK if it is OK for the size
1051    to change.  By OK to change, we mean that we shouldn't warn if the
1052    type or size does change.  */
1053 
1054 static bool
_bfd_elf_merge_symbol(bfd * abfd,struct bfd_link_info * info,const char * name,Elf_Internal_Sym * sym,asection ** psec,bfd_vma * pvalue,struct elf_link_hash_entry ** sym_hash,bfd ** poldbfd,bool * pold_weak,unsigned int * pold_alignment,bool * skip,bfd ** override,bool * type_change_ok,bool * size_change_ok,bool * matched)1055 _bfd_elf_merge_symbol (bfd *abfd,
1056 		       struct bfd_link_info *info,
1057 		       const char *name,
1058 		       Elf_Internal_Sym *sym,
1059 		       asection **psec,
1060 		       bfd_vma *pvalue,
1061 		       struct elf_link_hash_entry **sym_hash,
1062 		       bfd **poldbfd,
1063 		       bool *pold_weak,
1064 		       unsigned int *pold_alignment,
1065 		       bool *skip,
1066 		       bfd **override,
1067 		       bool *type_change_ok,
1068 		       bool *size_change_ok,
1069 		       bool *matched)
1070 {
1071   asection *sec, *oldsec;
1072   struct elf_link_hash_entry *h;
1073   struct elf_link_hash_entry *hi;
1074   struct elf_link_hash_entry *flip;
1075   int bind;
1076   bfd *oldbfd;
1077   bool newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
1078   bool newweak, oldweak, newfunc, oldfunc;
1079   const struct elf_backend_data *bed;
1080   char *new_version;
1081   bool default_sym = *matched;
1082 
1083   *skip = false;
1084   *override = NULL;
1085 
1086   sec = *psec;
1087   bind = ELF_ST_BIND (sym->st_info);
1088 
1089   if (! bfd_is_und_section (sec))
1090     h = elf_link_hash_lookup (elf_hash_table (info), name, true, false, false);
1091   else
1092     h = ((struct elf_link_hash_entry *)
1093 	 bfd_wrapped_link_hash_lookup (abfd, info, name, true, false, false));
1094   if (h == NULL)
1095     return false;
1096   *sym_hash = h;
1097 
1098   bed = get_elf_backend_data (abfd);
1099 
1100   /* NEW_VERSION is the symbol version of the new symbol.  */
1101   if (h->versioned != unversioned)
1102     {
1103       /* Symbol version is unknown or versioned.  */
1104       new_version = strrchr (name, ELF_VER_CHR);
1105       if (new_version)
1106 	{
1107 	  if (h->versioned == unknown)
1108 	    {
1109 	      if (new_version > name && new_version[-1] != ELF_VER_CHR)
1110 		h->versioned = versioned_hidden;
1111 	      else
1112 		h->versioned = versioned;
1113 	    }
1114 	  new_version += 1;
1115 	  if (new_version[0] == '\0')
1116 	    new_version = NULL;
1117 	}
1118       else
1119 	h->versioned = unversioned;
1120     }
1121   else
1122     new_version = NULL;
1123 
1124   /* For merging, we only care about real symbols.  But we need to make
1125      sure that indirect symbol dynamic flags are updated.  */
1126   hi = h;
1127   while (h->root.type == bfd_link_hash_indirect
1128 	 || h->root.type == bfd_link_hash_warning)
1129     h = (struct elf_link_hash_entry *) h->root.u.i.link;
1130 
1131   if (!*matched)
1132     {
1133       if (hi == h || h->root.type == bfd_link_hash_new)
1134 	*matched = true;
1135       else
1136 	{
1137 	  /* OLD_HIDDEN is true if the existing symbol is only visible
1138 	     to the symbol with the same symbol version.  NEW_HIDDEN is
1139 	     true if the new symbol is only visible to the symbol with
1140 	     the same symbol version.  */
1141 	  bool old_hidden = h->versioned == versioned_hidden;
1142 	  bool new_hidden = hi->versioned == versioned_hidden;
1143 	  if (!old_hidden && !new_hidden)
1144 	    /* The new symbol matches the existing symbol if both
1145 	       aren't hidden.  */
1146 	    *matched = true;
1147 	  else
1148 	    {
1149 	      /* OLD_VERSION is the symbol version of the existing
1150 		 symbol. */
1151 	      char *old_version;
1152 
1153 	      if (h->versioned >= versioned)
1154 		old_version = strrchr (h->root.root.string,
1155 				       ELF_VER_CHR) + 1;
1156 	      else
1157 		 old_version = NULL;
1158 
1159 	      /* The new symbol matches the existing symbol if they
1160 		 have the same symbol version.  */
1161 	      *matched = (old_version == new_version
1162 			  || (old_version != NULL
1163 			      && new_version != NULL
1164 			      && strcmp (old_version, new_version) == 0));
1165 	    }
1166 	}
1167     }
1168 
1169   /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
1170      existing symbol.  */
1171 
1172   oldbfd = NULL;
1173   oldsec = NULL;
1174   switch (h->root.type)
1175     {
1176     default:
1177       break;
1178 
1179     case bfd_link_hash_undefined:
1180     case bfd_link_hash_undefweak:
1181       oldbfd = h->root.u.undef.abfd;
1182       break;
1183 
1184     case bfd_link_hash_defined:
1185     case bfd_link_hash_defweak:
1186       oldbfd = h->root.u.def.section->owner;
1187       oldsec = h->root.u.def.section;
1188       break;
1189 
1190     case bfd_link_hash_common:
1191       oldbfd = h->root.u.c.p->section->owner;
1192       oldsec = h->root.u.c.p->section;
1193       if (pold_alignment)
1194 	*pold_alignment = h->root.u.c.p->alignment_power;
1195       break;
1196     }
1197   if (poldbfd && *poldbfd == NULL)
1198     *poldbfd = oldbfd;
1199 
1200   /* Differentiate strong and weak symbols.  */
1201   newweak = bind == STB_WEAK;
1202   oldweak = (h->root.type == bfd_link_hash_defweak
1203 	     || h->root.type == bfd_link_hash_undefweak);
1204   if (pold_weak)
1205     *pold_weak = oldweak;
1206 
1207   /* We have to check it for every instance since the first few may be
1208      references and not all compilers emit symbol type for undefined
1209      symbols.  */
1210   bfd_elf_link_mark_dynamic_symbol (info, h, sym);
1211 
1212   /* NEWDYN and OLDDYN indicate whether the new or old symbol,
1213      respectively, is from a dynamic object.  */
1214 
1215   newdyn = (abfd->flags & DYNAMIC) != 0;
1216 
1217   /* ref_dynamic_nonweak and dynamic_def flags track actual undefined
1218      syms and defined syms in dynamic libraries respectively.
1219      ref_dynamic on the other hand can be set for a symbol defined in
1220      a dynamic library, and def_dynamic may not be set;  When the
1221      definition in a dynamic lib is overridden by a definition in the
1222      executable use of the symbol in the dynamic lib becomes a
1223      reference to the executable symbol.  */
1224   if (newdyn)
1225     {
1226       if (bfd_is_und_section (sec))
1227 	{
1228 	  if (bind != STB_WEAK)
1229 	    {
1230 	      h->ref_dynamic_nonweak = 1;
1231 	      hi->ref_dynamic_nonweak = 1;
1232 	    }
1233 	}
1234       else
1235 	{
1236 	  /* Update the existing symbol only if they match. */
1237 	  if (*matched)
1238 	    h->dynamic_def = 1;
1239 	  hi->dynamic_def = 1;
1240 	}
1241     }
1242 
1243   /* If we just created the symbol, mark it as being an ELF symbol.
1244      Other than that, there is nothing to do--there is no merge issue
1245      with a newly defined symbol--so we just return.  */
1246 
1247   if (h->root.type == bfd_link_hash_new)
1248     {
1249       h->non_elf = 0;
1250       return true;
1251     }
1252 
1253   /* In cases involving weak versioned symbols, we may wind up trying
1254      to merge a symbol with itself.  Catch that here, to avoid the
1255      confusion that results if we try to override a symbol with
1256      itself.  The additional tests catch cases like
1257      _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
1258      dynamic object, which we do want to handle here.  */
1259   if (abfd == oldbfd
1260       && (newweak || oldweak)
1261       && ((abfd->flags & DYNAMIC) == 0
1262 	  || !h->def_regular))
1263     return true;
1264 
1265   olddyn = false;
1266   if (oldbfd != NULL)
1267     olddyn = (oldbfd->flags & DYNAMIC) != 0;
1268   else if (oldsec != NULL)
1269     {
1270       /* This handles the special SHN_MIPS_{TEXT,DATA} section
1271 	 indices used by MIPS ELF.  */
1272       olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
1273     }
1274 
1275   /* Handle a case where plugin_notice won't be called and thus won't
1276      set the non_ir_ref flags on the first pass over symbols.  */
1277   if (oldbfd != NULL
1278       && (oldbfd->flags & BFD_PLUGIN) != (abfd->flags & BFD_PLUGIN)
1279       && newdyn != olddyn)
1280     {
1281       h->root.non_ir_ref_dynamic = true;
1282       hi->root.non_ir_ref_dynamic = true;
1283     }
1284 
1285   /* NEWDEF and OLDDEF indicate whether the new or old symbol,
1286      respectively, appear to be a definition rather than reference.  */
1287 
1288   newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
1289 
1290   olddef = (h->root.type != bfd_link_hash_undefined
1291 	    && h->root.type != bfd_link_hash_undefweak
1292 	    && h->root.type != bfd_link_hash_common);
1293 
1294   /* NEWFUNC and OLDFUNC indicate whether the new or old symbol,
1295      respectively, appear to be a function.  */
1296 
1297   newfunc = (ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1298 	     && bed->is_function_type (ELF_ST_TYPE (sym->st_info)));
1299 
1300   oldfunc = (h->type != STT_NOTYPE
1301 	     && bed->is_function_type (h->type));
1302 
1303   if (!(newfunc && oldfunc)
1304       && ELF_ST_TYPE (sym->st_info) != h->type
1305       && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
1306       && h->type != STT_NOTYPE
1307       && (newdef || bfd_is_com_section (sec))
1308       && (olddef || h->root.type == bfd_link_hash_common))
1309     {
1310       /* If creating a default indirect symbol ("foo" or "foo@") from
1311 	 a dynamic versioned definition ("foo@@") skip doing so if
1312 	 there is an existing regular definition with a different
1313 	 type.  We don't want, for example, a "time" variable in the
1314 	 executable overriding a "time" function in a shared library.  */
1315       if (newdyn
1316 	  && !olddyn)
1317 	{
1318 	  *skip = true;
1319 	  return true;
1320 	}
1321 
1322       /* When adding a symbol from a regular object file after we have
1323 	 created indirect symbols, undo the indirection and any
1324 	 dynamic state.  */
1325       if (hi != h
1326 	  && !newdyn
1327 	  && olddyn)
1328 	{
1329 	  h = hi;
1330 	  (*bed->elf_backend_hide_symbol) (info, h, true);
1331 	  h->forced_local = 0;
1332 	  h->ref_dynamic = 0;
1333 	  h->def_dynamic = 0;
1334 	  h->dynamic_def = 0;
1335 	  if (h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1336 	    {
1337 	      h->root.type = bfd_link_hash_undefined;
1338 	      h->root.u.undef.abfd = abfd;
1339 	    }
1340 	  else
1341 	    {
1342 	      h->root.type = bfd_link_hash_new;
1343 	      h->root.u.undef.abfd = NULL;
1344 	    }
1345 	  return true;
1346 	}
1347     }
1348 
1349   /* Check TLS symbols.  We don't check undefined symbols introduced
1350      by "ld -u" which have no type (and oldbfd NULL), and we don't
1351      check symbols from plugins because they also have no type.  */
1352   if (oldbfd != NULL
1353       && (oldbfd->flags & BFD_PLUGIN) == 0
1354       && (abfd->flags & BFD_PLUGIN) == 0
1355       && ELF_ST_TYPE (sym->st_info) != h->type
1356       && (ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS))
1357     {
1358       bfd *ntbfd, *tbfd;
1359       bool ntdef, tdef;
1360       asection *ntsec, *tsec;
1361 
1362       if (h->type == STT_TLS)
1363 	{
1364 	  ntbfd = abfd;
1365 	  ntsec = sec;
1366 	  ntdef = newdef;
1367 	  tbfd = oldbfd;
1368 	  tsec = oldsec;
1369 	  tdef = olddef;
1370 	}
1371       else
1372 	{
1373 	  ntbfd = oldbfd;
1374 	  ntsec = oldsec;
1375 	  ntdef = olddef;
1376 	  tbfd = abfd;
1377 	  tsec = sec;
1378 	  tdef = newdef;
1379 	}
1380 
1381       if (tdef && ntdef)
1382 	_bfd_error_handler
1383 	  /* xgettext:c-format */
1384 	  (_("%s: TLS definition in %pB section %pA "
1385 	     "mismatches non-TLS definition in %pB section %pA"),
1386 	   h->root.root.string, tbfd, tsec, ntbfd, ntsec);
1387       else if (!tdef && !ntdef)
1388 	_bfd_error_handler
1389 	  /* xgettext:c-format */
1390 	  (_("%s: TLS reference in %pB "
1391 	     "mismatches non-TLS reference in %pB"),
1392 	   h->root.root.string, tbfd, ntbfd);
1393       else if (tdef)
1394 	_bfd_error_handler
1395 	  /* xgettext:c-format */
1396 	  (_("%s: TLS definition in %pB section %pA "
1397 	     "mismatches non-TLS reference in %pB"),
1398 	   h->root.root.string, tbfd, tsec, ntbfd);
1399       else
1400 	_bfd_error_handler
1401 	  /* xgettext:c-format */
1402 	  (_("%s: TLS reference in %pB "
1403 	     "mismatches non-TLS definition in %pB section %pA"),
1404 	   h->root.root.string, tbfd, ntbfd, ntsec);
1405 
1406       bfd_set_error (bfd_error_bad_value);
1407       return false;
1408     }
1409 
1410   /* If the old symbol has non-default visibility, we ignore the new
1411      definition from a dynamic object.  */
1412   if (newdyn
1413       && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1414       && !bfd_is_und_section (sec))
1415     {
1416       *skip = true;
1417       /* Make sure this symbol is dynamic.  */
1418       h->ref_dynamic = 1;
1419       hi->ref_dynamic = 1;
1420       /* A protected symbol has external availability. Make sure it is
1421 	 recorded as dynamic.
1422 
1423 	 FIXME: Should we check type and size for protected symbol?  */
1424       if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
1425 	return bfd_elf_link_record_dynamic_symbol (info, h);
1426       else
1427 	return true;
1428     }
1429   else if (!newdyn
1430 	   && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1431 	   && h->def_dynamic)
1432     {
1433       /* If the new symbol with non-default visibility comes from a
1434 	 relocatable file and the old definition comes from a dynamic
1435 	 object, we remove the old definition.  */
1436       if (hi->root.type == bfd_link_hash_indirect)
1437 	{
1438 	  /* Handle the case where the old dynamic definition is
1439 	     default versioned.  We need to copy the symbol info from
1440 	     the symbol with default version to the normal one if it
1441 	     was referenced before.  */
1442 	  if (h->ref_regular)
1443 	    {
1444 	      hi->root.type = h->root.type;
1445 	      h->root.type = bfd_link_hash_indirect;
1446 	      (*bed->elf_backend_copy_indirect_symbol) (info, hi, h);
1447 
1448 	      h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1449 	      if (ELF_ST_VISIBILITY (sym->st_other) != STV_PROTECTED)
1450 		{
1451 		  /* If the new symbol is hidden or internal, completely undo
1452 		     any dynamic link state.  */
1453 		  (*bed->elf_backend_hide_symbol) (info, h, true);
1454 		  h->forced_local = 0;
1455 		  h->ref_dynamic = 0;
1456 		}
1457 	      else
1458 		h->ref_dynamic = 1;
1459 
1460 	      h->def_dynamic = 0;
1461 	      /* FIXME: Should we check type and size for protected symbol?  */
1462 	      h->size = 0;
1463 	      h->type = 0;
1464 
1465 	      h = hi;
1466 	    }
1467 	  else
1468 	    h = hi;
1469 	}
1470 
1471       /* If the old symbol was undefined before, then it will still be
1472 	 on the undefs list.  If the new symbol is undefined or
1473 	 common, we can't make it bfd_link_hash_new here, because new
1474 	 undefined or common symbols will be added to the undefs list
1475 	 by _bfd_generic_link_add_one_symbol.  Symbols may not be
1476 	 added twice to the undefs list.  Also, if the new symbol is
1477 	 undefweak then we don't want to lose the strong undef.  */
1478       if (h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1479 	{
1480 	  h->root.type = bfd_link_hash_undefined;
1481 	  h->root.u.undef.abfd = abfd;
1482 	}
1483       else
1484 	{
1485 	  h->root.type = bfd_link_hash_new;
1486 	  h->root.u.undef.abfd = NULL;
1487 	}
1488 
1489       if (ELF_ST_VISIBILITY (sym->st_other) != STV_PROTECTED)
1490 	{
1491 	  /* If the new symbol is hidden or internal, completely undo
1492 	     any dynamic link state.  */
1493 	  (*bed->elf_backend_hide_symbol) (info, h, true);
1494 	  h->forced_local = 0;
1495 	  h->ref_dynamic = 0;
1496 	}
1497       else
1498 	h->ref_dynamic = 1;
1499       h->def_dynamic = 0;
1500       /* FIXME: Should we check type and size for protected symbol?  */
1501       h->size = 0;
1502       h->type = 0;
1503       return true;
1504     }
1505 
1506   /* If a new weak symbol definition comes from a regular file and the
1507      old symbol comes from a dynamic library, we treat the new one as
1508      strong.  Similarly, an old weak symbol definition from a regular
1509      file is treated as strong when the new symbol comes from a dynamic
1510      library.  Further, an old weak symbol from a dynamic library is
1511      treated as strong if the new symbol is from a dynamic library.
1512      This reflects the way glibc's ld.so works.
1513 
1514      Also allow a weak symbol to override a linker script symbol
1515      defined by an early pass over the script.  This is done so the
1516      linker knows the symbol is defined in an object file, for the
1517      DEFINED script function.
1518 
1519      Do this before setting *type_change_ok or *size_change_ok so that
1520      we warn properly when dynamic library symbols are overridden.  */
1521 
1522   if (newdef && !newdyn && (olddyn || h->root.ldscript_def))
1523     newweak = false;
1524   if (olddef && newdyn)
1525     oldweak = false;
1526 
1527   /* Allow changes between different types of function symbol.  */
1528   if (newfunc && oldfunc)
1529     *type_change_ok = true;
1530 
1531   /* It's OK to change the type if either the existing symbol or the
1532      new symbol is weak.  A type change is also OK if the old symbol
1533      is undefined and the new symbol is defined.  */
1534 
1535   if (oldweak
1536       || newweak
1537       || (newdef
1538 	  && h->root.type == bfd_link_hash_undefined))
1539     *type_change_ok = true;
1540 
1541   /* It's OK to change the size if either the existing symbol or the
1542      new symbol is weak, or if the old symbol is undefined.  */
1543 
1544   if (*type_change_ok
1545       || h->root.type == bfd_link_hash_undefined)
1546     *size_change_ok = true;
1547 
1548   /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1549      symbol, respectively, appears to be a common symbol in a dynamic
1550      object.  If a symbol appears in an uninitialized section, and is
1551      not weak, and is not a function, then it may be a common symbol
1552      which was resolved when the dynamic object was created.  We want
1553      to treat such symbols specially, because they raise special
1554      considerations when setting the symbol size: if the symbol
1555      appears as a common symbol in a regular object, and the size in
1556      the regular object is larger, we must make sure that we use the
1557      larger size.  This problematic case can always be avoided in C,
1558      but it must be handled correctly when using Fortran shared
1559      libraries.
1560 
1561      Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1562      likewise for OLDDYNCOMMON and OLDDEF.
1563 
1564      Note that this test is just a heuristic, and that it is quite
1565      possible to have an uninitialized symbol in a shared object which
1566      is really a definition, rather than a common symbol.  This could
1567      lead to some minor confusion when the symbol really is a common
1568      symbol in some regular object.  However, I think it will be
1569      harmless.  */
1570 
1571   if (newdyn
1572       && newdef
1573       && !newweak
1574       && (sec->flags & SEC_ALLOC) != 0
1575       && (sec->flags & SEC_LOAD) == 0
1576       && sym->st_size > 0
1577       && !newfunc)
1578     newdyncommon = true;
1579   else
1580     newdyncommon = false;
1581 
1582   if (olddyn
1583       && olddef
1584       && h->root.type == bfd_link_hash_defined
1585       && h->def_dynamic
1586       && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1587       && (h->root.u.def.section->flags & SEC_LOAD) == 0
1588       && h->size > 0
1589       && !oldfunc)
1590     olddyncommon = true;
1591   else
1592     olddyncommon = false;
1593 
1594   /* We now know everything about the old and new symbols.  We ask the
1595      backend to check if we can merge them.  */
1596   if (bed->merge_symbol != NULL)
1597     {
1598       if (!bed->merge_symbol (h, sym, psec, newdef, olddef, oldbfd, oldsec))
1599 	return false;
1600       sec = *psec;
1601     }
1602 
1603   /* There are multiple definitions of a normal symbol.  Skip the
1604      default symbol as well as definition from an IR object.  */
1605   if (olddef && !olddyn && !oldweak && newdef && !newdyn && !newweak
1606       && !default_sym && h->def_regular
1607       && !(oldbfd != NULL
1608 	   && (oldbfd->flags & BFD_PLUGIN) != 0
1609 	   && (abfd->flags & BFD_PLUGIN) == 0))
1610     {
1611       /* Handle a multiple definition.  */
1612       (*info->callbacks->multiple_definition) (info, &h->root,
1613 					       abfd, sec, *pvalue);
1614       *skip = true;
1615       return true;
1616     }
1617 
1618   /* If both the old and the new symbols look like common symbols in a
1619      dynamic object, set the size of the symbol to the larger of the
1620      two.  */
1621 
1622   if (olddyncommon
1623       && newdyncommon
1624       && sym->st_size != h->size)
1625     {
1626       /* Since we think we have two common symbols, issue a multiple
1627 	 common warning if desired.  Note that we only warn if the
1628 	 size is different.  If the size is the same, we simply let
1629 	 the old symbol override the new one as normally happens with
1630 	 symbols defined in dynamic objects.  */
1631 
1632       (*info->callbacks->multiple_common) (info, &h->root, abfd,
1633 					   bfd_link_hash_common, sym->st_size);
1634       if (sym->st_size > h->size)
1635 	h->size = sym->st_size;
1636 
1637       *size_change_ok = true;
1638     }
1639 
1640   /* If we are looking at a dynamic object, and we have found a
1641      definition, we need to see if the symbol was already defined by
1642      some other object.  If so, we want to use the existing
1643      definition, and we do not want to report a multiple symbol
1644      definition error; we do this by clobbering *PSEC to be
1645      bfd_und_section_ptr.
1646 
1647      We treat a common symbol as a definition if the symbol in the
1648      shared library is a function, since common symbols always
1649      represent variables; this can cause confusion in principle, but
1650      any such confusion would seem to indicate an erroneous program or
1651      shared library.  We also permit a common symbol in a regular
1652      object to override a weak symbol in a shared object.  */
1653 
1654   if (newdyn
1655       && newdef
1656       && (olddef
1657 	  || (h->root.type == bfd_link_hash_common
1658 	      && (newweak || newfunc))))
1659     {
1660       *override = abfd;
1661       newdef = false;
1662       newdyncommon = false;
1663 
1664       *psec = sec = bfd_und_section_ptr;
1665       *size_change_ok = true;
1666 
1667       /* If we get here when the old symbol is a common symbol, then
1668 	 we are explicitly letting it override a weak symbol or
1669 	 function in a dynamic object, and we don't want to warn about
1670 	 a type change.  If the old symbol is a defined symbol, a type
1671 	 change warning may still be appropriate.  */
1672 
1673       if (h->root.type == bfd_link_hash_common)
1674 	*type_change_ok = true;
1675     }
1676 
1677   /* Handle the special case of an old common symbol merging with a
1678      new symbol which looks like a common symbol in a shared object.
1679      We change *PSEC and *PVALUE to make the new symbol look like a
1680      common symbol, and let _bfd_generic_link_add_one_symbol do the
1681      right thing.  */
1682 
1683   if (newdyncommon
1684       && h->root.type == bfd_link_hash_common)
1685     {
1686       *override = oldbfd;
1687       newdef = false;
1688       newdyncommon = false;
1689       *pvalue = sym->st_size;
1690       *psec = sec = bed->common_section (oldsec);
1691       *size_change_ok = true;
1692     }
1693 
1694   /* Skip weak definitions of symbols that are already defined.  */
1695   if (newdef && olddef && newweak)
1696     {
1697       /* Don't skip new non-IR weak syms.  */
1698       if (!(oldbfd != NULL
1699 	    && (oldbfd->flags & BFD_PLUGIN) != 0
1700 	    && (abfd->flags & BFD_PLUGIN) == 0))
1701 	{
1702 	  newdef = false;
1703 	  *skip = true;
1704 	}
1705 
1706       /* Merge st_other.  If the symbol already has a dynamic index,
1707 	 but visibility says it should not be visible, turn it into a
1708 	 local symbol.  */
1709       elf_merge_st_other (abfd, h, sym->st_other, sec, newdef, newdyn);
1710       if (h->dynindx != -1)
1711 	switch (ELF_ST_VISIBILITY (h->other))
1712 	  {
1713 	  case STV_INTERNAL:
1714 	  case STV_HIDDEN:
1715 	    (*bed->elf_backend_hide_symbol) (info, h, true);
1716 	    break;
1717 	  }
1718     }
1719 
1720   /* If the old symbol is from a dynamic object, and the new symbol is
1721      a definition which is not from a dynamic object, then the new
1722      symbol overrides the old symbol.  Symbols from regular files
1723      always take precedence over symbols from dynamic objects, even if
1724      they are defined after the dynamic object in the link.
1725 
1726      As above, we again permit a common symbol in a regular object to
1727      override a definition in a shared object if the shared object
1728      symbol is a function or is weak.  */
1729 
1730   flip = NULL;
1731   if (!newdyn
1732       && (newdef
1733 	  || (bfd_is_com_section (sec)
1734 	      && (oldweak || oldfunc)))
1735       && olddyn
1736       && olddef
1737       && h->def_dynamic)
1738     {
1739       /* Change the hash table entry to undefined, and let
1740 	 _bfd_generic_link_add_one_symbol do the right thing with the
1741 	 new definition.  */
1742 
1743       h->root.type = bfd_link_hash_undefined;
1744       h->root.u.undef.abfd = h->root.u.def.section->owner;
1745       *size_change_ok = true;
1746 
1747       olddef = false;
1748       olddyncommon = false;
1749 
1750       /* We again permit a type change when a common symbol may be
1751 	 overriding a function.  */
1752 
1753       if (bfd_is_com_section (sec))
1754 	{
1755 	  if (oldfunc)
1756 	    {
1757 	      /* If a common symbol overrides a function, make sure
1758 		 that it isn't defined dynamically nor has type
1759 		 function.  */
1760 	      h->def_dynamic = 0;
1761 	      h->type = STT_NOTYPE;
1762 	    }
1763 	  *type_change_ok = true;
1764 	}
1765 
1766       if (hi->root.type == bfd_link_hash_indirect)
1767 	flip = hi;
1768       else
1769 	/* This union may have been set to be non-NULL when this symbol
1770 	   was seen in a dynamic object.  We must force the union to be
1771 	   NULL, so that it is correct for a regular symbol.  */
1772 	h->verinfo.vertree = NULL;
1773     }
1774 
1775   /* Handle the special case of a new common symbol merging with an
1776      old symbol that looks like it might be a common symbol defined in
1777      a shared object.  Note that we have already handled the case in
1778      which a new common symbol should simply override the definition
1779      in the shared library.  */
1780 
1781   if (! newdyn
1782       && bfd_is_com_section (sec)
1783       && olddyncommon)
1784     {
1785       /* It would be best if we could set the hash table entry to a
1786 	 common symbol, but we don't know what to use for the section
1787 	 or the alignment.  */
1788       (*info->callbacks->multiple_common) (info, &h->root, abfd,
1789 					   bfd_link_hash_common, sym->st_size);
1790 
1791       /* If the presumed common symbol in the dynamic object is
1792 	 larger, pretend that the new symbol has its size.  */
1793 
1794       if (h->size > *pvalue)
1795 	*pvalue = h->size;
1796 
1797       /* We need to remember the alignment required by the symbol
1798 	 in the dynamic object.  */
1799       BFD_ASSERT (pold_alignment);
1800       *pold_alignment = h->root.u.def.section->alignment_power;
1801 
1802       olddef = false;
1803       olddyncommon = false;
1804 
1805       h->root.type = bfd_link_hash_undefined;
1806       h->root.u.undef.abfd = h->root.u.def.section->owner;
1807 
1808       *size_change_ok = true;
1809       *type_change_ok = true;
1810 
1811       if (hi->root.type == bfd_link_hash_indirect)
1812 	flip = hi;
1813       else
1814 	h->verinfo.vertree = NULL;
1815     }
1816 
1817   if (flip != NULL)
1818     {
1819       /* Handle the case where we had a versioned symbol in a dynamic
1820 	 library and now find a definition in a normal object.  In this
1821 	 case, we make the versioned symbol point to the normal one.  */
1822       flip->root.type = h->root.type;
1823       flip->root.u.undef.abfd = h->root.u.undef.abfd;
1824       h->root.type = bfd_link_hash_indirect;
1825       h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1826       (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1827       if (h->def_dynamic)
1828 	{
1829 	  h->def_dynamic = 0;
1830 	  flip->ref_dynamic = 1;
1831 	}
1832     }
1833 
1834   return true;
1835 }
1836 
1837 /* This function is called to create an indirect symbol from the
1838    default for the symbol with the default version if needed. The
1839    symbol is described by H, NAME, SYM, SEC, and VALUE.  We
1840    set DYNSYM if the new indirect symbol is dynamic.  */
1841 
1842 static bool
_bfd_elf_add_default_symbol(bfd * abfd,struct bfd_link_info * info,struct elf_link_hash_entry * h,const char * name,Elf_Internal_Sym * sym,asection * sec,bfd_vma value,bfd ** poldbfd,bool * dynsym)1843 _bfd_elf_add_default_symbol (bfd *abfd,
1844 			     struct bfd_link_info *info,
1845 			     struct elf_link_hash_entry *h,
1846 			     const char *name,
1847 			     Elf_Internal_Sym *sym,
1848 			     asection *sec,
1849 			     bfd_vma value,
1850 			     bfd **poldbfd,
1851 			     bool *dynsym)
1852 {
1853   bool type_change_ok;
1854   bool size_change_ok;
1855   bool skip;
1856   char *shortname;
1857   struct elf_link_hash_entry *hi;
1858   struct bfd_link_hash_entry *bh;
1859   const struct elf_backend_data *bed;
1860   bool collect;
1861   bool dynamic;
1862   bfd *override;
1863   char *p;
1864   size_t len, shortlen;
1865   asection *tmp_sec;
1866   bool matched;
1867 
1868   if (h->versioned == unversioned || h->versioned == versioned_hidden)
1869     return true;
1870 
1871   /* If this symbol has a version, and it is the default version, we
1872      create an indirect symbol from the default name to the fully
1873      decorated name.  This will cause external references which do not
1874      specify a version to be bound to this version of the symbol.  */
1875   p = strchr (name, ELF_VER_CHR);
1876   if (h->versioned == unknown)
1877     {
1878       if (p == NULL)
1879 	{
1880 	  h->versioned = unversioned;
1881 	  return true;
1882 	}
1883       else
1884 	{
1885 	  if (p[1] != ELF_VER_CHR)
1886 	    {
1887 	      h->versioned = versioned_hidden;
1888 	      return true;
1889 	    }
1890 	  else
1891 	    h->versioned = versioned;
1892 	}
1893     }
1894   else
1895     {
1896       /* PR ld/19073: We may see an unversioned definition after the
1897 	 default version.  */
1898       if (p == NULL)
1899 	return true;
1900     }
1901 
1902   bed = get_elf_backend_data (abfd);
1903   collect = bed->collect;
1904   dynamic = (abfd->flags & DYNAMIC) != 0;
1905 
1906   shortlen = p - name;
1907   shortname = (char *) bfd_hash_allocate (&info->hash->table, shortlen + 1);
1908   if (shortname == NULL)
1909     return false;
1910   memcpy (shortname, name, shortlen);
1911   shortname[shortlen] = '\0';
1912 
1913   /* We are going to create a new symbol.  Merge it with any existing
1914      symbol with this name.  For the purposes of the merge, act as
1915      though we were defining the symbol we just defined, although we
1916      actually going to define an indirect symbol.  */
1917   type_change_ok = false;
1918   size_change_ok = false;
1919   matched = true;
1920   tmp_sec = sec;
1921   if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &tmp_sec, &value,
1922 			      &hi, poldbfd, NULL, NULL, &skip, &override,
1923 			      &type_change_ok, &size_change_ok, &matched))
1924     return false;
1925 
1926   if (skip)
1927     goto nondefault;
1928 
1929   if (hi->def_regular || ELF_COMMON_DEF_P (hi))
1930     {
1931       /* If the undecorated symbol will have a version added by a
1932 	 script different to H, then don't indirect to/from the
1933 	 undecorated symbol.  This isn't ideal because we may not yet
1934 	 have seen symbol versions, if given by a script on the
1935 	 command line rather than via --version-script.  */
1936       if (hi->verinfo.vertree == NULL && info->version_info != NULL)
1937 	{
1938 	  bool hide;
1939 
1940 	  hi->verinfo.vertree
1941 	    = bfd_find_version_for_sym (info->version_info,
1942 					hi->root.root.string, &hide);
1943 	  if (hi->verinfo.vertree != NULL && hide)
1944 	    {
1945 	      (*bed->elf_backend_hide_symbol) (info, hi, true);
1946 	      goto nondefault;
1947 	    }
1948 	}
1949       if (hi->verinfo.vertree != NULL
1950 	  && strcmp (p + 1 + (p[1] == '@'), hi->verinfo.vertree->name) != 0)
1951 	goto nondefault;
1952     }
1953 
1954   if (! override)
1955     {
1956       /* Add the default symbol if not performing a relocatable link.  */
1957       if (! bfd_link_relocatable (info))
1958 	{
1959 	  bh = &hi->root;
1960 	  if (bh->type == bfd_link_hash_defined
1961 	      && bh->u.def.section->owner != NULL
1962 	      && (bh->u.def.section->owner->flags & BFD_PLUGIN) != 0)
1963 	    {
1964 	      /* Mark the previous definition from IR object as
1965 		 undefined so that the generic linker will override
1966 		 it.  */
1967 	      bh->type = bfd_link_hash_undefined;
1968 	      bh->u.undef.abfd = bh->u.def.section->owner;
1969 	    }
1970 	  if (! (_bfd_generic_link_add_one_symbol
1971 		 (info, abfd, shortname, BSF_INDIRECT,
1972 		  bfd_ind_section_ptr,
1973 		  0, name, false, collect, &bh)))
1974 	    return false;
1975 	  hi = (struct elf_link_hash_entry *) bh;
1976 	}
1977     }
1978   else
1979     {
1980       /* In this case the symbol named SHORTNAME is overriding the
1981 	 indirect symbol we want to add.  We were planning on making
1982 	 SHORTNAME an indirect symbol referring to NAME.  SHORTNAME
1983 	 is the name without a version.  NAME is the fully versioned
1984 	 name, and it is the default version.
1985 
1986 	 Overriding means that we already saw a definition for the
1987 	 symbol SHORTNAME in a regular object, and it is overriding
1988 	 the symbol defined in the dynamic object.
1989 
1990 	 When this happens, we actually want to change NAME, the
1991 	 symbol we just added, to refer to SHORTNAME.  This will cause
1992 	 references to NAME in the shared object to become references
1993 	 to SHORTNAME in the regular object.  This is what we expect
1994 	 when we override a function in a shared object: that the
1995 	 references in the shared object will be mapped to the
1996 	 definition in the regular object.  */
1997 
1998       while (hi->root.type == bfd_link_hash_indirect
1999 	     || hi->root.type == bfd_link_hash_warning)
2000 	hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
2001 
2002       h->root.type = bfd_link_hash_indirect;
2003       h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
2004       if (h->def_dynamic)
2005 	{
2006 	  h->def_dynamic = 0;
2007 	  hi->ref_dynamic = 1;
2008 	  if (hi->ref_regular
2009 	      || hi->def_regular)
2010 	    {
2011 	      if (! bfd_elf_link_record_dynamic_symbol (info, hi))
2012 		return false;
2013 	    }
2014 	}
2015 
2016       /* Now set HI to H, so that the following code will set the
2017 	 other fields correctly.  */
2018       hi = h;
2019     }
2020 
2021   /* Check if HI is a warning symbol.  */
2022   if (hi->root.type == bfd_link_hash_warning)
2023     hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
2024 
2025   /* If there is a duplicate definition somewhere, then HI may not
2026      point to an indirect symbol.  We will have reported an error to
2027      the user in that case.  */
2028 
2029   if (hi->root.type == bfd_link_hash_indirect)
2030     {
2031       struct elf_link_hash_entry *ht;
2032 
2033       ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
2034       (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
2035 
2036       /* If we first saw a reference to SHORTNAME with non-default
2037 	 visibility, merge that visibility to the @@VER symbol.  */
2038       elf_merge_st_other (abfd, ht, hi->other, sec, true, dynamic);
2039 
2040       /* A reference to the SHORTNAME symbol from a dynamic library
2041 	 will be satisfied by the versioned symbol at runtime.  In
2042 	 effect, we have a reference to the versioned symbol.  */
2043       ht->ref_dynamic_nonweak |= hi->ref_dynamic_nonweak;
2044       hi->dynamic_def |= ht->dynamic_def;
2045 
2046       /* See if the new flags lead us to realize that the symbol must
2047 	 be dynamic.  */
2048       if (! *dynsym)
2049 	{
2050 	  if (! dynamic)
2051 	    {
2052 	      if (! bfd_link_executable (info)
2053 		  || hi->def_dynamic
2054 		  || hi->ref_dynamic)
2055 		*dynsym = true;
2056 	    }
2057 	  else
2058 	    {
2059 	      if (hi->ref_regular)
2060 		*dynsym = true;
2061 	    }
2062 	}
2063     }
2064 
2065   /* We also need to define an indirection from the nondefault version
2066      of the symbol.  */
2067 
2068  nondefault:
2069   len = strlen (name);
2070   shortname = (char *) bfd_hash_allocate (&info->hash->table, len);
2071   if (shortname == NULL)
2072     return false;
2073   memcpy (shortname, name, shortlen);
2074   memcpy (shortname + shortlen, p + 1, len - shortlen);
2075 
2076   /* Once again, merge with any existing symbol.  */
2077   type_change_ok = false;
2078   size_change_ok = false;
2079   tmp_sec = sec;
2080   if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &tmp_sec, &value,
2081 			      &hi, poldbfd, NULL, NULL, &skip, &override,
2082 			      &type_change_ok, &size_change_ok, &matched))
2083     return false;
2084 
2085   if (skip)
2086     {
2087       if (!dynamic
2088 	  && h->root.type == bfd_link_hash_defweak
2089 	  && hi->root.type == bfd_link_hash_defined)
2090 	{
2091 	  /* We are handling a weak sym@@ver and attempting to define
2092 	     a weak sym@ver, but _bfd_elf_merge_symbol said to skip the
2093 	     new weak sym@ver because there is already a strong sym@ver.
2094 	     However, sym@ver and sym@@ver are really the same symbol.
2095 	     The existing strong sym@ver ought to override sym@@ver.  */
2096 	  h->root.type = bfd_link_hash_defined;
2097 	  h->root.u.def.section = hi->root.u.def.section;
2098 	  h->root.u.def.value = hi->root.u.def.value;
2099 	  hi->root.type = bfd_link_hash_indirect;
2100 	  hi->root.u.i.link = &h->root;
2101 	}
2102       else
2103 	return true;
2104     }
2105   else if (override)
2106     {
2107       /* Here SHORTNAME is a versioned name, so we don't expect to see
2108 	 the type of override we do in the case above unless it is
2109 	 overridden by a versioned definition.  */
2110       if (hi->root.type != bfd_link_hash_defined
2111 	  && hi->root.type != bfd_link_hash_defweak)
2112 	_bfd_error_handler
2113 	  /* xgettext:c-format */
2114 	  (_("%pB: unexpected redefinition of indirect versioned symbol `%s'"),
2115 	   abfd, shortname);
2116       return true;
2117     }
2118   else
2119     {
2120       bh = &hi->root;
2121       if (! (_bfd_generic_link_add_one_symbol
2122 	     (info, abfd, shortname, BSF_INDIRECT,
2123 	      bfd_ind_section_ptr, 0, name, false, collect, &bh)))
2124 	return false;
2125       hi = (struct elf_link_hash_entry *) bh;
2126     }
2127 
2128   /* If there is a duplicate definition somewhere, then HI may not
2129      point to an indirect symbol.  We will have reported an error
2130      to the user in that case.  */
2131   if (hi->root.type == bfd_link_hash_indirect)
2132     {
2133       (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
2134       h->ref_dynamic_nonweak |= hi->ref_dynamic_nonweak;
2135       hi->dynamic_def |= h->dynamic_def;
2136 
2137       /* If we first saw a reference to @VER symbol with
2138 	 non-default visibility, merge that visibility to the
2139 	 @@VER symbol.  */
2140       elf_merge_st_other (abfd, h, hi->other, sec, true, dynamic);
2141 
2142       /* See if the new flags lead us to realize that the symbol
2143 	 must be dynamic.  */
2144       if (! *dynsym)
2145 	{
2146 	  if (! dynamic)
2147 	    {
2148 	      if (! bfd_link_executable (info)
2149 		  || hi->ref_dynamic)
2150 		*dynsym = true;
2151 	    }
2152 	  else
2153 	    {
2154 	      if (hi->ref_regular)
2155 		*dynsym = true;
2156 	    }
2157 	}
2158     }
2159 
2160   return true;
2161 }
2162 
2163 /* This routine is used to export all defined symbols into the dynamic
2164    symbol table.  It is called via elf_link_hash_traverse.  */
2165 
2166 static bool
_bfd_elf_export_symbol(struct elf_link_hash_entry * h,void * data)2167 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
2168 {
2169   struct elf_info_failed *eif = (struct elf_info_failed *) data;
2170 
2171   /* Ignore indirect symbols.  These are added by the versioning code.  */
2172   if (h->root.type == bfd_link_hash_indirect)
2173     return true;
2174 
2175   /* Ignore this if we won't export it.  */
2176   if (!eif->info->export_dynamic && !h->dynamic)
2177     return true;
2178 
2179   if (h->dynindx == -1
2180       && (h->def_regular || h->ref_regular)
2181       && ! bfd_hide_sym_by_version (eif->info->version_info,
2182 				    h->root.root.string))
2183     {
2184       if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2185 	{
2186 	  eif->failed = true;
2187 	  return false;
2188 	}
2189     }
2190 
2191   return true;
2192 }
2193 
2194 /* Look through the symbols which are defined in other shared
2195    libraries and referenced here.  Update the list of version
2196    dependencies.  This will be put into the .gnu.version_r section.
2197    This function is called via elf_link_hash_traverse.  */
2198 
2199 static bool
_bfd_elf_link_find_version_dependencies(struct elf_link_hash_entry * h,void * data)2200 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
2201 					 void *data)
2202 {
2203   struct elf_find_verdep_info *rinfo = (struct elf_find_verdep_info *) data;
2204   Elf_Internal_Verneed *t;
2205   Elf_Internal_Vernaux *a;
2206   size_t amt;
2207 
2208   /* We only care about symbols defined in shared objects with version
2209      information.  */
2210   if (!h->def_dynamic
2211       || h->def_regular
2212       || h->dynindx == -1
2213       || h->verinfo.verdef == NULL
2214       || (elf_dyn_lib_class (h->verinfo.verdef->vd_bfd)
2215 	  & (DYN_AS_NEEDED | DYN_DT_NEEDED | DYN_NO_NEEDED)))
2216     return true;
2217 
2218   /* See if we already know about this version.  */
2219   for (t = elf_tdata (rinfo->info->output_bfd)->verref;
2220        t != NULL;
2221        t = t->vn_nextref)
2222     {
2223       if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
2224 	continue;
2225 
2226       for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
2227 	if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
2228 	  return true;
2229 
2230       break;
2231     }
2232 
2233   /* This is a new version.  Add it to tree we are building.  */
2234 
2235   if (t == NULL)
2236     {
2237       amt = sizeof *t;
2238       t = (Elf_Internal_Verneed *) bfd_zalloc (rinfo->info->output_bfd, amt);
2239       if (t == NULL)
2240 	{
2241 	  rinfo->failed = true;
2242 	  return false;
2243 	}
2244 
2245       t->vn_bfd = h->verinfo.verdef->vd_bfd;
2246       t->vn_nextref = elf_tdata (rinfo->info->output_bfd)->verref;
2247       elf_tdata (rinfo->info->output_bfd)->verref = t;
2248     }
2249 
2250   amt = sizeof *a;
2251   a = (Elf_Internal_Vernaux *) bfd_zalloc (rinfo->info->output_bfd, amt);
2252   if (a == NULL)
2253     {
2254       rinfo->failed = true;
2255       return false;
2256     }
2257 
2258   /* Note that we are copying a string pointer here, and testing it
2259      above.  If bfd_elf_string_from_elf_section is ever changed to
2260      discard the string data when low in memory, this will have to be
2261      fixed.  */
2262   a->vna_nodename = h->verinfo.verdef->vd_nodename;
2263 
2264   a->vna_flags = h->verinfo.verdef->vd_flags;
2265   a->vna_nextptr = t->vn_auxptr;
2266 
2267   h->verinfo.verdef->vd_exp_refno = rinfo->vers;
2268   ++rinfo->vers;
2269 
2270   a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
2271 
2272   t->vn_auxptr = a;
2273 
2274   return true;
2275 }
2276 
2277 /* Return TRUE and set *HIDE to TRUE if the versioned symbol is
2278    hidden.  Set *T_P to NULL if there is no match.  */
2279 
2280 static bool
_bfd_elf_link_hide_versioned_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,const char * version_p,struct bfd_elf_version_tree ** t_p,bool * hide)2281 _bfd_elf_link_hide_versioned_symbol (struct bfd_link_info *info,
2282 				     struct elf_link_hash_entry *h,
2283 				     const char *version_p,
2284 				     struct bfd_elf_version_tree **t_p,
2285 				     bool *hide)
2286 {
2287   struct bfd_elf_version_tree *t;
2288 
2289   /* Look for the version.  If we find it, it is no longer weak.  */
2290   for (t = info->version_info; t != NULL; t = t->next)
2291     {
2292       if (strcmp (t->name, version_p) == 0)
2293 	{
2294 	  size_t len;
2295 	  char *alc;
2296 	  struct bfd_elf_version_expr *d;
2297 
2298 	  len = version_p - h->root.root.string;
2299 	  alc = (char *) bfd_malloc (len);
2300 	  if (alc == NULL)
2301 	    return false;
2302 	  memcpy (alc, h->root.root.string, len - 1);
2303 	  alc[len - 1] = '\0';
2304 	  if (alc[len - 2] == ELF_VER_CHR)
2305 	    alc[len - 2] = '\0';
2306 
2307 	  h->verinfo.vertree = t;
2308 	  t->used = true;
2309 	  d = NULL;
2310 
2311 	  if (t->globals.list != NULL)
2312 	    d = (*t->match) (&t->globals, NULL, alc);
2313 
2314 	  /* See if there is anything to force this symbol to
2315 	     local scope.  */
2316 	  if (d == NULL && t->locals.list != NULL)
2317 	    {
2318 	      d = (*t->match) (&t->locals, NULL, alc);
2319 	      if (d != NULL
2320 		  && h->dynindx != -1
2321 		  && ! info->export_dynamic)
2322 		*hide = true;
2323 	    }
2324 
2325 	  free (alc);
2326 	  break;
2327 	}
2328     }
2329 
2330   *t_p = t;
2331 
2332   return true;
2333 }
2334 
2335 /* Return TRUE if the symbol H is hidden by version script.  */
2336 
2337 bool
_bfd_elf_link_hide_sym_by_version(struct bfd_link_info * info,struct elf_link_hash_entry * h)2338 _bfd_elf_link_hide_sym_by_version (struct bfd_link_info *info,
2339 				   struct elf_link_hash_entry *h)
2340 {
2341   const char *p;
2342   bool hide = false;
2343   const struct elf_backend_data *bed
2344     = get_elf_backend_data (info->output_bfd);
2345 
2346   /* Version script only hides symbols defined in regular objects.  */
2347   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
2348     return true;
2349 
2350   p = strchr (h->root.root.string, ELF_VER_CHR);
2351   if (p != NULL && h->verinfo.vertree == NULL)
2352     {
2353       struct bfd_elf_version_tree *t;
2354 
2355       ++p;
2356       if (*p == ELF_VER_CHR)
2357 	++p;
2358 
2359       if (*p != '\0'
2360 	  && _bfd_elf_link_hide_versioned_symbol (info, h, p, &t, &hide)
2361 	  && hide)
2362 	{
2363 	  if (hide)
2364 	    (*bed->elf_backend_hide_symbol) (info, h, true);
2365 	  return true;
2366 	}
2367     }
2368 
2369   /* If we don't have a version for this symbol, see if we can find
2370      something.  */
2371   if (h->verinfo.vertree == NULL && info->version_info != NULL)
2372     {
2373       h->verinfo.vertree
2374 	= bfd_find_version_for_sym (info->version_info,
2375 				    h->root.root.string, &hide);
2376       if (h->verinfo.vertree != NULL && hide)
2377 	{
2378 	  (*bed->elf_backend_hide_symbol) (info, h, true);
2379 	  return true;
2380 	}
2381     }
2382 
2383   return false;
2384 }
2385 
2386 /* Figure out appropriate versions for all the symbols.  We may not
2387    have the version number script until we have read all of the input
2388    files, so until that point we don't know which symbols should be
2389    local.  This function is called via elf_link_hash_traverse.  */
2390 
2391 static bool
_bfd_elf_link_assign_sym_version(struct elf_link_hash_entry * h,void * data)2392 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
2393 {
2394   struct elf_info_failed *sinfo;
2395   struct bfd_link_info *info;
2396   const struct elf_backend_data *bed;
2397   struct elf_info_failed eif;
2398   char *p;
2399   bool hide;
2400 
2401   sinfo = (struct elf_info_failed *) data;
2402   info = sinfo->info;
2403 
2404   /* Fix the symbol flags.  */
2405   eif.failed = false;
2406   eif.info = info;
2407   if (! _bfd_elf_fix_symbol_flags (h, &eif))
2408     {
2409       if (eif.failed)
2410 	sinfo->failed = true;
2411       return false;
2412     }
2413 
2414   bed = get_elf_backend_data (info->output_bfd);
2415 
2416   /* We only need version numbers for symbols defined in regular
2417      objects.  */
2418   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
2419     {
2420       /* Hide symbols defined in discarded input sections.  */
2421       if ((h->root.type == bfd_link_hash_defined
2422 	   || h->root.type == bfd_link_hash_defweak)
2423 	  && discarded_section (h->root.u.def.section))
2424 	(*bed->elf_backend_hide_symbol) (info, h, true);
2425       return true;
2426     }
2427 
2428   hide = false;
2429   p = strchr (h->root.root.string, ELF_VER_CHR);
2430   if (p != NULL && h->verinfo.vertree == NULL)
2431     {
2432       struct bfd_elf_version_tree *t;
2433 
2434       ++p;
2435       if (*p == ELF_VER_CHR)
2436 	++p;
2437 
2438       /* If there is no version string, we can just return out.  */
2439       if (*p == '\0')
2440 	return true;
2441 
2442       if (!_bfd_elf_link_hide_versioned_symbol (info, h, p, &t, &hide))
2443 	{
2444 	  sinfo->failed = true;
2445 	  return false;
2446 	}
2447 
2448       if (hide)
2449 	(*bed->elf_backend_hide_symbol) (info, h, true);
2450 
2451       /* If we are building an application, we need to create a
2452 	 version node for this version.  */
2453       if (t == NULL && bfd_link_executable (info))
2454 	{
2455 	  struct bfd_elf_version_tree **pp;
2456 	  int version_index;
2457 
2458 	  /* If we aren't going to export this symbol, we don't need
2459 	     to worry about it.  */
2460 	  if (h->dynindx == -1)
2461 	    return true;
2462 
2463 	  t = (struct bfd_elf_version_tree *) bfd_zalloc (info->output_bfd,
2464 							  sizeof *t);
2465 	  if (t == NULL)
2466 	    {
2467 	      sinfo->failed = true;
2468 	      return false;
2469 	    }
2470 
2471 	  t->name = p;
2472 	  t->name_indx = (unsigned int) -1;
2473 	  t->used = true;
2474 
2475 	  version_index = 1;
2476 	  /* Don't count anonymous version tag.  */
2477 	  if (sinfo->info->version_info != NULL
2478 	      && sinfo->info->version_info->vernum == 0)
2479 	    version_index = 0;
2480 	  for (pp = &sinfo->info->version_info;
2481 	       *pp != NULL;
2482 	       pp = &(*pp)->next)
2483 	    ++version_index;
2484 	  t->vernum = version_index;
2485 
2486 	  *pp = t;
2487 
2488 	  h->verinfo.vertree = t;
2489 	}
2490       else if (t == NULL)
2491 	{
2492 	  /* We could not find the version for a symbol when
2493 	     generating a shared archive.  Return an error.  */
2494 	  _bfd_error_handler
2495 	    /* xgettext:c-format */
2496 	    (_("%pB: version node not found for symbol %s"),
2497 	     info->output_bfd, h->root.root.string);
2498 	  bfd_set_error (bfd_error_bad_value);
2499 	  sinfo->failed = true;
2500 	  return false;
2501 	}
2502     }
2503 
2504   /* If we don't have a version for this symbol, see if we can find
2505      something.  */
2506   if (!hide
2507       && h->verinfo.vertree == NULL
2508       && sinfo->info->version_info != NULL)
2509     {
2510       h->verinfo.vertree
2511 	= bfd_find_version_for_sym (sinfo->info->version_info,
2512 				    h->root.root.string, &hide);
2513       if (h->verinfo.vertree != NULL && hide)
2514 	(*bed->elf_backend_hide_symbol) (info, h, true);
2515     }
2516 
2517   return true;
2518 }
2519 
2520 /* Read and swap the relocs from the section indicated by SHDR.  This
2521    may be either a REL or a RELA section.  The relocations are
2522    translated into RELA relocations and stored in INTERNAL_RELOCS,
2523    which should have already been allocated to contain enough space.
2524    The EXTERNAL_RELOCS are a buffer where the external form of the
2525    relocations should be stored.
2526 
2527    Returns FALSE if something goes wrong.  */
2528 
2529 static bool
elf_link_read_relocs_from_section(bfd * abfd,asection * sec,Elf_Internal_Shdr * shdr,void * external_relocs,Elf_Internal_Rela * internal_relocs)2530 elf_link_read_relocs_from_section (bfd *abfd,
2531 				   asection *sec,
2532 				   Elf_Internal_Shdr *shdr,
2533 				   void *external_relocs,
2534 				   Elf_Internal_Rela *internal_relocs)
2535 {
2536   const struct elf_backend_data *bed;
2537   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
2538   const bfd_byte *erela;
2539   const bfd_byte *erelaend;
2540   Elf_Internal_Rela *irela;
2541   Elf_Internal_Shdr *symtab_hdr;
2542   size_t nsyms;
2543 
2544   /* Position ourselves at the start of the section.  */
2545   if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
2546     return false;
2547 
2548   /* Read the relocations.  */
2549   if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
2550     return false;
2551 
2552   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
2553   nsyms = NUM_SHDR_ENTRIES (symtab_hdr);
2554 
2555   bed = get_elf_backend_data (abfd);
2556 
2557   /* Convert the external relocations to the internal format.  */
2558   if (shdr->sh_entsize == bed->s->sizeof_rel)
2559     swap_in = bed->s->swap_reloc_in;
2560   else if (shdr->sh_entsize == bed->s->sizeof_rela)
2561     swap_in = bed->s->swap_reloca_in;
2562   else
2563     {
2564       bfd_set_error (bfd_error_wrong_format);
2565       return false;
2566     }
2567 
2568   erela = (const bfd_byte *) external_relocs;
2569   /* Setting erelaend like this and comparing with <= handles case of
2570      a fuzzed object with sh_size not a multiple of sh_entsize.  */
2571   erelaend = erela + shdr->sh_size - shdr->sh_entsize;
2572   irela = internal_relocs;
2573   while (erela <= erelaend)
2574     {
2575       bfd_vma r_symndx;
2576 
2577       (*swap_in) (abfd, erela, irela);
2578       r_symndx = ELF32_R_SYM (irela->r_info);
2579       if (bed->s->arch_size == 64)
2580 	r_symndx >>= 24;
2581       if (nsyms > 0)
2582 	{
2583 	  if ((size_t) r_symndx >= nsyms)
2584 	    {
2585 	      _bfd_error_handler
2586 		/* xgettext:c-format */
2587 		(_("%pB: bad reloc symbol index (%#" PRIx64 " >= %#lx)"
2588 		   " for offset %#" PRIx64 " in section `%pA'"),
2589 		 abfd, (uint64_t) r_symndx, (unsigned long) nsyms,
2590 		 (uint64_t) irela->r_offset, sec);
2591 	      bfd_set_error (bfd_error_bad_value);
2592 	      return false;
2593 	    }
2594 	}
2595       else if (r_symndx != STN_UNDEF)
2596 	{
2597 	  _bfd_error_handler
2598 	    /* xgettext:c-format */
2599 	    (_("%pB: non-zero symbol index (%#" PRIx64 ")"
2600 	       " for offset %#" PRIx64 " in section `%pA'"
2601 	       " when the object file has no symbol table"),
2602 	     abfd, (uint64_t) r_symndx,
2603 	     (uint64_t) irela->r_offset, sec);
2604 	  bfd_set_error (bfd_error_bad_value);
2605 	  return false;
2606 	}
2607       irela += bed->s->int_rels_per_ext_rel;
2608       erela += shdr->sh_entsize;
2609     }
2610 
2611   return true;
2612 }
2613 
2614 /* Read and swap the relocs for a section O.  They may have been
2615    cached.  If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2616    not NULL, they are used as buffers to read into.  They are known to
2617    be large enough.  If the INTERNAL_RELOCS relocs argument is NULL,
2618    the return value is allocated using either malloc or bfd_alloc,
2619    according to the KEEP_MEMORY argument.  If O has two relocation
2620    sections (both REL and RELA relocations), then the REL_HDR
2621    relocations will appear first in INTERNAL_RELOCS, followed by the
2622    RELA_HDR relocations.  */
2623 
2624 Elf_Internal_Rela *
_bfd_elf_link_read_relocs(bfd * abfd,asection * o,void * external_relocs,Elf_Internal_Rela * internal_relocs,bool keep_memory)2625 _bfd_elf_link_read_relocs (bfd *abfd,
2626 			   asection *o,
2627 			   void *external_relocs,
2628 			   Elf_Internal_Rela *internal_relocs,
2629 			   bool keep_memory)
2630 {
2631   void *alloc1 = NULL;
2632   Elf_Internal_Rela *alloc2 = NULL;
2633   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2634   struct bfd_elf_section_data *esdo = elf_section_data (o);
2635   Elf_Internal_Rela *internal_rela_relocs;
2636 
2637   if (esdo->relocs != NULL)
2638     return esdo->relocs;
2639 
2640   if (o->reloc_count == 0)
2641     return NULL;
2642 
2643   if (internal_relocs == NULL)
2644     {
2645       bfd_size_type size;
2646 
2647       size = (bfd_size_type) o->reloc_count * sizeof (Elf_Internal_Rela);
2648       if (keep_memory)
2649 	internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_alloc (abfd, size);
2650       else
2651 	internal_relocs = alloc2 = (Elf_Internal_Rela *) bfd_malloc (size);
2652       if (internal_relocs == NULL)
2653 	goto error_return;
2654     }
2655 
2656   if (external_relocs == NULL)
2657     {
2658       bfd_size_type size = 0;
2659 
2660       if (esdo->rel.hdr)
2661 	size += esdo->rel.hdr->sh_size;
2662       if (esdo->rela.hdr)
2663 	size += esdo->rela.hdr->sh_size;
2664 
2665       alloc1 = bfd_malloc (size);
2666       if (alloc1 == NULL)
2667 	goto error_return;
2668       external_relocs = alloc1;
2669     }
2670 
2671   internal_rela_relocs = internal_relocs;
2672   if (esdo->rel.hdr)
2673     {
2674       if (!elf_link_read_relocs_from_section (abfd, o, esdo->rel.hdr,
2675 					      external_relocs,
2676 					      internal_relocs))
2677 	goto error_return;
2678       external_relocs = (((bfd_byte *) external_relocs)
2679 			 + esdo->rel.hdr->sh_size);
2680       internal_rela_relocs += (NUM_SHDR_ENTRIES (esdo->rel.hdr)
2681 			       * bed->s->int_rels_per_ext_rel);
2682     }
2683 
2684   if (esdo->rela.hdr
2685       && (!elf_link_read_relocs_from_section (abfd, o, esdo->rela.hdr,
2686 					      external_relocs,
2687 					      internal_rela_relocs)))
2688     goto error_return;
2689 
2690   /* Cache the results for next time, if we can.  */
2691   if (keep_memory)
2692     esdo->relocs = internal_relocs;
2693 
2694   free (alloc1);
2695 
2696   /* Don't free alloc2, since if it was allocated we are passing it
2697      back (under the name of internal_relocs).  */
2698 
2699   return internal_relocs;
2700 
2701  error_return:
2702   free (alloc1);
2703   if (alloc2 != NULL)
2704     {
2705       if (keep_memory)
2706 	bfd_release (abfd, alloc2);
2707       else
2708 	free (alloc2);
2709     }
2710   return NULL;
2711 }
2712 
2713 /* Compute the size of, and allocate space for, REL_HDR which is the
2714    section header for a section containing relocations for O.  */
2715 
2716 static bool
_bfd_elf_link_size_reloc_section(bfd * abfd,struct bfd_elf_section_reloc_data * reldata)2717 _bfd_elf_link_size_reloc_section (bfd *abfd,
2718 				  struct bfd_elf_section_reloc_data *reldata)
2719 {
2720   Elf_Internal_Shdr *rel_hdr = reldata->hdr;
2721 
2722   /* That allows us to calculate the size of the section.  */
2723   rel_hdr->sh_size = rel_hdr->sh_entsize * reldata->count;
2724 
2725   /* The contents field must last into write_object_contents, so we
2726      allocate it with bfd_alloc rather than malloc.  Also since we
2727      cannot be sure that the contents will actually be filled in,
2728      we zero the allocated space.  */
2729   rel_hdr->contents = (unsigned char *) bfd_zalloc (abfd, rel_hdr->sh_size);
2730   if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2731     return false;
2732 
2733   if (reldata->hashes == NULL && reldata->count)
2734     {
2735       struct elf_link_hash_entry **p;
2736 
2737       p = ((struct elf_link_hash_entry **)
2738 	   bfd_zmalloc (reldata->count * sizeof (*p)));
2739       if (p == NULL)
2740 	return false;
2741 
2742       reldata->hashes = p;
2743     }
2744 
2745   return true;
2746 }
2747 
2748 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2749    originated from the section given by INPUT_REL_HDR) to the
2750    OUTPUT_BFD.  */
2751 
2752 bool
_bfd_elf_link_output_relocs(bfd * output_bfd,asection * input_section,Elf_Internal_Shdr * input_rel_hdr,Elf_Internal_Rela * internal_relocs,struct elf_link_hash_entry ** rel_hash ATTRIBUTE_UNUSED)2753 _bfd_elf_link_output_relocs (bfd *output_bfd,
2754 			     asection *input_section,
2755 			     Elf_Internal_Shdr *input_rel_hdr,
2756 			     Elf_Internal_Rela *internal_relocs,
2757 			     struct elf_link_hash_entry **rel_hash
2758 			       ATTRIBUTE_UNUSED)
2759 {
2760   Elf_Internal_Rela *irela;
2761   Elf_Internal_Rela *irelaend;
2762   bfd_byte *erel;
2763   struct bfd_elf_section_reloc_data *output_reldata;
2764   asection *output_section;
2765   const struct elf_backend_data *bed;
2766   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2767   struct bfd_elf_section_data *esdo;
2768 
2769   output_section = input_section->output_section;
2770 
2771   bed = get_elf_backend_data (output_bfd);
2772   esdo = elf_section_data (output_section);
2773   if (esdo->rel.hdr && esdo->rel.hdr->sh_entsize == input_rel_hdr->sh_entsize)
2774     {
2775       output_reldata = &esdo->rel;
2776       swap_out = bed->s->swap_reloc_out;
2777     }
2778   else if (esdo->rela.hdr
2779 	   && esdo->rela.hdr->sh_entsize == input_rel_hdr->sh_entsize)
2780     {
2781       output_reldata = &esdo->rela;
2782       swap_out = bed->s->swap_reloca_out;
2783     }
2784   else
2785     {
2786       _bfd_error_handler
2787 	/* xgettext:c-format */
2788 	(_("%pB: relocation size mismatch in %pB section %pA"),
2789 	 output_bfd, input_section->owner, input_section);
2790       bfd_set_error (bfd_error_wrong_format);
2791       return false;
2792     }
2793 
2794   erel = output_reldata->hdr->contents;
2795   erel += output_reldata->count * input_rel_hdr->sh_entsize;
2796   irela = internal_relocs;
2797   irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2798 		      * bed->s->int_rels_per_ext_rel);
2799   while (irela < irelaend)
2800     {
2801       (*swap_out) (output_bfd, irela, erel);
2802       irela += bed->s->int_rels_per_ext_rel;
2803       erel += input_rel_hdr->sh_entsize;
2804     }
2805 
2806   /* Bump the counter, so that we know where to add the next set of
2807      relocations.  */
2808   output_reldata->count += NUM_SHDR_ENTRIES (input_rel_hdr);
2809 
2810   return true;
2811 }
2812 
2813 /* Make weak undefined symbols in PIE dynamic.  */
2814 
2815 bool
_bfd_elf_link_hash_fixup_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)2816 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2817 				 struct elf_link_hash_entry *h)
2818 {
2819   if (bfd_link_pie (info)
2820       && h->dynindx == -1
2821       && h->root.type == bfd_link_hash_undefweak)
2822     return bfd_elf_link_record_dynamic_symbol (info, h);
2823 
2824   return true;
2825 }
2826 
2827 /* Fix up the flags for a symbol.  This handles various cases which
2828    can only be fixed after all the input files are seen.  This is
2829    currently called by both adjust_dynamic_symbol and
2830    assign_sym_version, which is unnecessary but perhaps more robust in
2831    the face of future changes.  */
2832 
2833 static bool
_bfd_elf_fix_symbol_flags(struct elf_link_hash_entry * h,struct elf_info_failed * eif)2834 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2835 			   struct elf_info_failed *eif)
2836 {
2837   const struct elf_backend_data *bed;
2838 
2839   /* If this symbol was mentioned in a non-ELF file, try to set
2840      DEF_REGULAR and REF_REGULAR correctly.  This is the only way to
2841      permit a non-ELF file to correctly refer to a symbol defined in
2842      an ELF dynamic object.  */
2843   if (h->non_elf)
2844     {
2845       while (h->root.type == bfd_link_hash_indirect)
2846 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
2847 
2848       if (h->root.type != bfd_link_hash_defined
2849 	  && h->root.type != bfd_link_hash_defweak)
2850 	{
2851 	  h->ref_regular = 1;
2852 	  h->ref_regular_nonweak = 1;
2853 	}
2854       else
2855 	{
2856 	  if (h->root.u.def.section->owner != NULL
2857 	      && (bfd_get_flavour (h->root.u.def.section->owner)
2858 		  == bfd_target_elf_flavour))
2859 	    {
2860 	      h->ref_regular = 1;
2861 	      h->ref_regular_nonweak = 1;
2862 	    }
2863 	  else
2864 	    h->def_regular = 1;
2865 	}
2866 
2867       if (h->dynindx == -1
2868 	  && (h->def_dynamic
2869 	      || h->ref_dynamic))
2870 	{
2871 	  if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2872 	    {
2873 	      eif->failed = true;
2874 	      return false;
2875 	    }
2876 	}
2877     }
2878   else
2879     {
2880       /* Unfortunately, NON_ELF is only correct if the symbol
2881 	 was first seen in a non-ELF file.  Fortunately, if the symbol
2882 	 was first seen in an ELF file, we're probably OK unless the
2883 	 symbol was defined in a non-ELF file.  Catch that case here.
2884 	 FIXME: We're still in trouble if the symbol was first seen in
2885 	 a dynamic object, and then later in a non-ELF regular object.  */
2886       if ((h->root.type == bfd_link_hash_defined
2887 	   || h->root.type == bfd_link_hash_defweak)
2888 	  && !h->def_regular
2889 	  && (h->root.u.def.section->owner != NULL
2890 	      ? (bfd_get_flavour (h->root.u.def.section->owner)
2891 		 != bfd_target_elf_flavour)
2892 	      : (bfd_is_abs_section (h->root.u.def.section)
2893 		 && !h->def_dynamic)))
2894 	h->def_regular = 1;
2895     }
2896 
2897   /* Backend specific symbol fixup.  */
2898   bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2899   if (bed->elf_backend_fixup_symbol
2900       && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
2901     return false;
2902 
2903   /* If this is a final link, and the symbol was defined as a common
2904      symbol in a regular object file, and there was no definition in
2905      any dynamic object, then the linker will have allocated space for
2906      the symbol in a common section but the DEF_REGULAR
2907      flag will not have been set.  */
2908   if (h->root.type == bfd_link_hash_defined
2909       && !h->def_regular
2910       && h->ref_regular
2911       && !h->def_dynamic
2912       && (h->root.u.def.section->owner->flags & (DYNAMIC | BFD_PLUGIN)) == 0)
2913     h->def_regular = 1;
2914 
2915   /* Symbols defined in discarded sections shouldn't be dynamic.  */
2916   if (h->root.type == bfd_link_hash_undefined && h->indx == -3)
2917     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
2918 
2919   /* If a weak undefined symbol has non-default visibility, we also
2920      hide it from the dynamic linker.  */
2921   else if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2922 	   && h->root.type == bfd_link_hash_undefweak)
2923     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
2924 
2925   /* A hidden versioned symbol in executable should be forced local if
2926      it is is locally defined, not referenced by shared library and not
2927      exported.  */
2928   else if (bfd_link_executable (eif->info)
2929 	   && h->versioned == versioned_hidden
2930 	   && !eif->info->export_dynamic
2931 	   && !h->dynamic
2932 	   && !h->ref_dynamic
2933 	   && h->def_regular)
2934     (*bed->elf_backend_hide_symbol) (eif->info, h, true);
2935 
2936   /* If -Bsymbolic was used (which means to bind references to global
2937      symbols to the definition within the shared object), and this
2938      symbol was defined in a regular object, then it actually doesn't
2939      need a PLT entry.  Likewise, if the symbol has non-default
2940      visibility.  If the symbol has hidden or internal visibility, we
2941      will force it local.  */
2942   else if (h->needs_plt
2943 	   && bfd_link_pic (eif->info)
2944 	   && is_elf_hash_table (eif->info->hash)
2945 	   && (SYMBOLIC_BIND (eif->info, h)
2946 	       || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2947 	   && h->def_regular)
2948     {
2949       bool force_local;
2950 
2951       force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2952 		     || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2953       (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2954     }
2955 
2956   /* If this is a weak defined symbol in a dynamic object, and we know
2957      the real definition in the dynamic object, copy interesting flags
2958      over to the real definition.  */
2959   if (h->is_weakalias)
2960     {
2961       struct elf_link_hash_entry *def = weakdef (h);
2962 
2963       /* If the real definition is defined by a regular object file,
2964 	 don't do anything special.  See the longer description in
2965 	 _bfd_elf_adjust_dynamic_symbol, below.  If the def is not
2966 	 bfd_link_hash_defined as it was when put on the alias list
2967 	 then it must have originally been a versioned symbol (for
2968 	 which a non-versioned indirect symbol is created) and later
2969 	 a definition for the non-versioned symbol is found.  In that
2970 	 case the indirection is flipped with the versioned symbol
2971 	 becoming an indirect pointing at the non-versioned symbol.
2972 	 Thus, not an alias any more.  */
2973       if (def->def_regular
2974 	  || def->root.type != bfd_link_hash_defined)
2975 	{
2976 	  h = def;
2977 	  while ((h = h->u.alias) != def)
2978 	    h->is_weakalias = 0;
2979 	}
2980       else
2981 	{
2982 	  while (h->root.type == bfd_link_hash_indirect)
2983 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
2984 	  BFD_ASSERT (h->root.type == bfd_link_hash_defined
2985 		      || h->root.type == bfd_link_hash_defweak);
2986 	  BFD_ASSERT (def->def_dynamic);
2987 	  (*bed->elf_backend_copy_indirect_symbol) (eif->info, def, h);
2988 	}
2989     }
2990 
2991   return true;
2992 }
2993 
2994 /* Make the backend pick a good value for a dynamic symbol.  This is
2995    called via elf_link_hash_traverse, and also calls itself
2996    recursively.  */
2997 
2998 static bool
_bfd_elf_adjust_dynamic_symbol(struct elf_link_hash_entry * h,void * data)2999 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
3000 {
3001   struct elf_info_failed *eif = (struct elf_info_failed *) data;
3002   struct elf_link_hash_table *htab;
3003   const struct elf_backend_data *bed;
3004 
3005   if (! is_elf_hash_table (eif->info->hash))
3006     return false;
3007 
3008   /* Ignore indirect symbols.  These are added by the versioning code.  */
3009   if (h->root.type == bfd_link_hash_indirect)
3010     return true;
3011 
3012   /* Fix the symbol flags.  */
3013   if (! _bfd_elf_fix_symbol_flags (h, eif))
3014     return false;
3015 
3016   htab = elf_hash_table (eif->info);
3017   bed = get_elf_backend_data (htab->dynobj);
3018 
3019   if (h->root.type == bfd_link_hash_undefweak)
3020     {
3021       if (eif->info->dynamic_undefined_weak == 0)
3022 	(*bed->elf_backend_hide_symbol) (eif->info, h, true);
3023       else if (eif->info->dynamic_undefined_weak > 0
3024 	       && h->ref_regular
3025 	       && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
3026 	       && !bfd_hide_sym_by_version (eif->info->version_info,
3027 					    h->root.root.string))
3028 	{
3029 	  if (!bfd_elf_link_record_dynamic_symbol (eif->info, h))
3030 	    {
3031 	      eif->failed = true;
3032 	      return false;
3033 	    }
3034 	}
3035     }
3036 
3037   /* If this symbol does not require a PLT entry, and it is not
3038      defined by a dynamic object, or is not referenced by a regular
3039      object, ignore it.  We do have to handle a weak defined symbol,
3040      even if no regular object refers to it, if we decided to add it
3041      to the dynamic symbol table.  FIXME: Do we normally need to worry
3042      about symbols which are defined by one dynamic object and
3043      referenced by another one?  */
3044   if (!h->needs_plt
3045       && h->type != STT_GNU_IFUNC
3046       && (h->def_regular
3047 	  || !h->def_dynamic
3048 	  || (!h->ref_regular
3049 	      && (!h->is_weakalias || weakdef (h)->dynindx == -1))))
3050     {
3051       h->plt = elf_hash_table (eif->info)->init_plt_offset;
3052       return true;
3053     }
3054 
3055   /* If we've already adjusted this symbol, don't do it again.  This
3056      can happen via a recursive call.  */
3057   if (h->dynamic_adjusted)
3058     return true;
3059 
3060   /* Don't look at this symbol again.  Note that we must set this
3061      after checking the above conditions, because we may look at a
3062      symbol once, decide not to do anything, and then get called
3063      recursively later after REF_REGULAR is set below.  */
3064   h->dynamic_adjusted = 1;
3065 
3066   /* If this is a weak definition, and we know a real definition, and
3067      the real symbol is not itself defined by a regular object file,
3068      then get a good value for the real definition.  We handle the
3069      real symbol first, for the convenience of the backend routine.
3070 
3071      Note that there is a confusing case here.  If the real definition
3072      is defined by a regular object file, we don't get the real symbol
3073      from the dynamic object, but we do get the weak symbol.  If the
3074      processor backend uses a COPY reloc, then if some routine in the
3075      dynamic object changes the real symbol, we will not see that
3076      change in the corresponding weak symbol.  This is the way other
3077      ELF linkers work as well, and seems to be a result of the shared
3078      library model.
3079 
3080      I will clarify this issue.  Most SVR4 shared libraries define the
3081      variable _timezone and define timezone as a weak synonym.  The
3082      tzset call changes _timezone.  If you write
3083        extern int timezone;
3084        int _timezone = 5;
3085        int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
3086      you might expect that, since timezone is a synonym for _timezone,
3087      the same number will print both times.  However, if the processor
3088      backend uses a COPY reloc, then actually timezone will be copied
3089      into your process image, and, since you define _timezone
3090      yourself, _timezone will not.  Thus timezone and _timezone will
3091      wind up at different memory locations.  The tzset call will set
3092      _timezone, leaving timezone unchanged.  */
3093 
3094   if (h->is_weakalias)
3095     {
3096       struct elf_link_hash_entry *def = weakdef (h);
3097 
3098       /* If we get to this point, there is an implicit reference to
3099 	 the alias by a regular object file via the weak symbol H.  */
3100       def->ref_regular = 1;
3101 
3102       /* Ensure that the backend adjust_dynamic_symbol function sees
3103 	 the strong alias before H by recursively calling ourselves.  */
3104       if (!_bfd_elf_adjust_dynamic_symbol (def, eif))
3105 	return false;
3106     }
3107 
3108   /* If a symbol has no type and no size and does not require a PLT
3109      entry, then we are probably about to do the wrong thing here: we
3110      are probably going to create a COPY reloc for an empty object.
3111      This case can arise when a shared object is built with assembly
3112      code, and the assembly code fails to set the symbol type.  */
3113   if (h->size == 0
3114       && h->type == STT_NOTYPE
3115       && !h->needs_plt)
3116     _bfd_error_handler
3117       (_("warning: type and size of dynamic symbol `%s' are not defined"),
3118        h->root.root.string);
3119 
3120   if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
3121     {
3122       eif->failed = true;
3123       return false;
3124     }
3125 
3126   return true;
3127 }
3128 
3129 /* Adjust the dynamic symbol, H, for copy in the dynamic bss section,
3130    DYNBSS.  */
3131 
3132 bool
_bfd_elf_adjust_dynamic_copy(struct bfd_link_info * info,struct elf_link_hash_entry * h,asection * dynbss)3133 _bfd_elf_adjust_dynamic_copy (struct bfd_link_info *info,
3134 			      struct elf_link_hash_entry *h,
3135 			      asection *dynbss)
3136 {
3137   unsigned int power_of_two;
3138   bfd_vma mask;
3139   asection *sec = h->root.u.def.section;
3140 
3141   /* The section alignment of the definition is the maximum alignment
3142      requirement of symbols defined in the section.  Since we don't
3143      know the symbol alignment requirement, we start with the
3144      maximum alignment and check low bits of the symbol address
3145      for the minimum alignment.  */
3146   power_of_two = bfd_section_alignment (sec);
3147   mask = ((bfd_vma) 1 << power_of_two) - 1;
3148   while ((h->root.u.def.value & mask) != 0)
3149     {
3150        mask >>= 1;
3151        --power_of_two;
3152     }
3153 
3154   if (power_of_two > bfd_section_alignment (dynbss))
3155     {
3156       /* Adjust the section alignment if needed.  */
3157       if (!bfd_set_section_alignment (dynbss, power_of_two))
3158 	return false;
3159     }
3160 
3161   /* We make sure that the symbol will be aligned properly.  */
3162   dynbss->size = BFD_ALIGN (dynbss->size, mask + 1);
3163 
3164   /* Define the symbol as being at this point in DYNBSS.  */
3165   h->root.u.def.section = dynbss;
3166   h->root.u.def.value = dynbss->size;
3167 
3168   /* Increment the size of DYNBSS to make room for the symbol.  */
3169   dynbss->size += h->size;
3170 
3171   /* No error if extern_protected_data is true.  */
3172   if (h->protected_def
3173       && (!info->extern_protected_data
3174 	  || (info->extern_protected_data < 0
3175 	      && !get_elf_backend_data (dynbss->owner)->extern_protected_data)))
3176     info->callbacks->einfo
3177       (_("%P: copy reloc against protected `%pT' is dangerous\n"),
3178        h->root.root.string);
3179 
3180   return true;
3181 }
3182 
3183 /* Adjust all external symbols pointing into SEC_MERGE sections
3184    to reflect the object merging within the sections.  */
3185 
3186 static bool
_bfd_elf_link_sec_merge_syms(struct elf_link_hash_entry * h,void * data)3187 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
3188 {
3189   asection *sec;
3190 
3191   if ((h->root.type == bfd_link_hash_defined
3192        || h->root.type == bfd_link_hash_defweak)
3193       && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
3194       && sec->sec_info_type == SEC_INFO_TYPE_MERGE)
3195     {
3196       bfd *output_bfd = (bfd *) data;
3197 
3198       h->root.u.def.value =
3199 	_bfd_merged_section_offset (output_bfd,
3200 				    &h->root.u.def.section,
3201 				    elf_section_data (sec)->sec_info,
3202 				    h->root.u.def.value);
3203     }
3204 
3205   return true;
3206 }
3207 
3208 /* Returns false if the symbol referred to by H should be considered
3209    to resolve local to the current module, and true if it should be
3210    considered to bind dynamically.  */
3211 
3212 bool
_bfd_elf_dynamic_symbol_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bool not_local_protected)3213 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
3214 			   struct bfd_link_info *info,
3215 			   bool not_local_protected)
3216 {
3217   bool binding_stays_local_p;
3218   const struct elf_backend_data *bed;
3219   struct elf_link_hash_table *hash_table;
3220 
3221   if (h == NULL)
3222     return false;
3223 
3224   while (h->root.type == bfd_link_hash_indirect
3225 	 || h->root.type == bfd_link_hash_warning)
3226     h = (struct elf_link_hash_entry *) h->root.u.i.link;
3227 
3228   /* If it was forced local, then clearly it's not dynamic.  */
3229   if (h->dynindx == -1)
3230     return false;
3231   if (h->forced_local)
3232     return false;
3233 
3234   /* Identify the cases where name binding rules say that a
3235      visible symbol resolves locally.  */
3236   binding_stays_local_p = (bfd_link_executable (info)
3237 			   || SYMBOLIC_BIND (info, h));
3238 
3239   switch (ELF_ST_VISIBILITY (h->other))
3240     {
3241     case STV_INTERNAL:
3242     case STV_HIDDEN:
3243       return false;
3244 
3245     case STV_PROTECTED:
3246       hash_table = elf_hash_table (info);
3247       if (!is_elf_hash_table (&hash_table->root))
3248 	return false;
3249 
3250       bed = get_elf_backend_data (hash_table->dynobj);
3251 
3252       /* Proper resolution for function pointer equality may require
3253 	 that these symbols perhaps be resolved dynamically, even though
3254 	 we should be resolving them to the current module.  */
3255       if (!not_local_protected || !bed->is_function_type (h->type))
3256 	binding_stays_local_p = true;
3257       break;
3258 
3259     default:
3260       break;
3261     }
3262 
3263   /* If it isn't defined locally, then clearly it's dynamic.  */
3264   if (!h->def_regular && !ELF_COMMON_DEF_P (h))
3265     return true;
3266 
3267   /* Otherwise, the symbol is dynamic if binding rules don't tell
3268      us that it remains local.  */
3269   return !binding_stays_local_p;
3270 }
3271 
3272 /* Return true if the symbol referred to by H should be considered
3273    to resolve local to the current module, and false otherwise.  Differs
3274    from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
3275    undefined symbols.  The two functions are virtually identical except
3276    for the place where dynindx == -1 is tested.  If that test is true,
3277    _bfd_elf_dynamic_symbol_p will say the symbol is local, while
3278    _bfd_elf_symbol_refs_local_p will say the symbol is local only for
3279    defined symbols.
3280    It might seem that _bfd_elf_dynamic_symbol_p could be rewritten as
3281    !_bfd_elf_symbol_refs_local_p, except that targets differ in their
3282    treatment of undefined weak symbols.  For those that do not make
3283    undefined weak symbols dynamic, both functions may return false.  */
3284 
3285 bool
_bfd_elf_symbol_refs_local_p(struct elf_link_hash_entry * h,struct bfd_link_info * info,bool local_protected)3286 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
3287 			      struct bfd_link_info *info,
3288 			      bool local_protected)
3289 {
3290   const struct elf_backend_data *bed;
3291   struct elf_link_hash_table *hash_table;
3292 
3293   /* If it's a local sym, of course we resolve locally.  */
3294   if (h == NULL)
3295     return true;
3296 
3297   /* STV_HIDDEN or STV_INTERNAL ones must be local.  */
3298   if (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
3299       || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL)
3300     return true;
3301 
3302   /* Forced local symbols resolve locally.  */
3303   if (h->forced_local)
3304     return true;
3305 
3306   /* Common symbols that become definitions don't get the DEF_REGULAR
3307      flag set, so test it first, and don't bail out.  */
3308   if (ELF_COMMON_DEF_P (h))
3309     /* Do nothing.  */;
3310   /* If we don't have a definition in a regular file, then we can't
3311      resolve locally.  The sym is either undefined or dynamic.  */
3312   else if (!h->def_regular)
3313     return false;
3314 
3315   /* Non-dynamic symbols resolve locally.  */
3316   if (h->dynindx == -1)
3317     return true;
3318 
3319   /* At this point, we know the symbol is defined and dynamic.  In an
3320      executable it must resolve locally, likewise when building symbolic
3321      shared libraries.  */
3322   if (bfd_link_executable (info) || SYMBOLIC_BIND (info, h))
3323     return true;
3324 
3325   /* Now deal with defined dynamic symbols in shared libraries.  Ones
3326      with default visibility might not resolve locally.  */
3327   if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
3328     return false;
3329 
3330   hash_table = elf_hash_table (info);
3331   if (!is_elf_hash_table (&hash_table->root))
3332     return true;
3333 
3334   bed = get_elf_backend_data (hash_table->dynobj);
3335 
3336   /* If extern_protected_data is false, STV_PROTECTED non-function
3337      symbols are local.  */
3338   if ((!info->extern_protected_data
3339        || (info->extern_protected_data < 0
3340 	   && !bed->extern_protected_data))
3341       && !bed->is_function_type (h->type))
3342     return true;
3343 
3344   /* Function pointer equality tests may require that STV_PROTECTED
3345      symbols be treated as dynamic symbols.  If the address of a
3346      function not defined in an executable is set to that function's
3347      plt entry in the executable, then the address of the function in
3348      a shared library must also be the plt entry in the executable.  */
3349   return local_protected;
3350 }
3351 
3352 /* Caches some TLS segment info, and ensures that the TLS segment vma is
3353    aligned.  Returns the first TLS output section.  */
3354 
3355 struct bfd_section *
_bfd_elf_tls_setup(bfd * obfd,struct bfd_link_info * info)3356 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
3357 {
3358   struct bfd_section *sec, *tls;
3359   unsigned int align = 0;
3360 
3361   for (sec = obfd->sections; sec != NULL; sec = sec->next)
3362     if ((sec->flags & SEC_THREAD_LOCAL) != 0)
3363       break;
3364   tls = sec;
3365 
3366   for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
3367     if (sec->alignment_power > align)
3368       align = sec->alignment_power;
3369 
3370   elf_hash_table (info)->tls_sec = tls;
3371 
3372   /* Ensure the alignment of the first section (usually .tdata) is the largest
3373      alignment, so that the tls segment starts aligned.  */
3374   if (tls != NULL)
3375     tls->alignment_power = align;
3376 
3377   return tls;
3378 }
3379 
3380 /* Return TRUE iff this is a non-common, definition of a non-function symbol.  */
3381 static bool
is_global_data_symbol_definition(bfd * abfd ATTRIBUTE_UNUSED,Elf_Internal_Sym * sym)3382 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
3383 				  Elf_Internal_Sym *sym)
3384 {
3385   const struct elf_backend_data *bed;
3386 
3387   /* Local symbols do not count, but target specific ones might.  */
3388   if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
3389       && ELF_ST_BIND (sym->st_info) < STB_LOOS)
3390     return false;
3391 
3392   bed = get_elf_backend_data (abfd);
3393   /* Function symbols do not count.  */
3394   if (bed->is_function_type (ELF_ST_TYPE (sym->st_info)))
3395     return false;
3396 
3397   /* If the section is undefined, then so is the symbol.  */
3398   if (sym->st_shndx == SHN_UNDEF)
3399     return false;
3400 
3401   /* If the symbol is defined in the common section, then
3402      it is a common definition and so does not count.  */
3403   if (bed->common_definition (sym))
3404     return false;
3405 
3406   /* If the symbol is in a target specific section then we
3407      must rely upon the backend to tell us what it is.  */
3408   if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
3409     /* FIXME - this function is not coded yet:
3410 
3411        return _bfd_is_global_symbol_definition (abfd, sym);
3412 
3413        Instead for now assume that the definition is not global,
3414        Even if this is wrong, at least the linker will behave
3415        in the same way that it used to do.  */
3416     return false;
3417 
3418   return true;
3419 }
3420 
3421 /* Search the symbol table of the archive element of the archive ABFD
3422    whose archive map contains a mention of SYMDEF, and determine if
3423    the symbol is defined in this element.  */
3424 static bool
elf_link_is_defined_archive_symbol(bfd * abfd,carsym * symdef)3425 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
3426 {
3427   Elf_Internal_Shdr * hdr;
3428   size_t symcount;
3429   size_t extsymcount;
3430   size_t extsymoff;
3431   Elf_Internal_Sym *isymbuf;
3432   Elf_Internal_Sym *isym;
3433   Elf_Internal_Sym *isymend;
3434   bool result;
3435 
3436   abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
3437   if (abfd == NULL)
3438     return false;
3439 
3440   if (! bfd_check_format (abfd, bfd_object))
3441     return false;
3442 
3443   /* Select the appropriate symbol table.  If we don't know if the
3444      object file is an IR object, give linker LTO plugin a chance to
3445      get the correct symbol table.  */
3446   if (abfd->plugin_format == bfd_plugin_yes
3447 #if BFD_SUPPORTS_PLUGINS
3448       || (abfd->plugin_format == bfd_plugin_unknown
3449 	  && bfd_link_plugin_object_p (abfd))
3450 #endif
3451       )
3452     {
3453       /* Use the IR symbol table if the object has been claimed by
3454 	 plugin.  */
3455       abfd = abfd->plugin_dummy_bfd;
3456       hdr = &elf_tdata (abfd)->symtab_hdr;
3457     }
3458   else if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
3459     hdr = &elf_tdata (abfd)->symtab_hdr;
3460   else
3461     hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3462 
3463   symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
3464 
3465   /* The sh_info field of the symtab header tells us where the
3466      external symbols start.  We don't care about the local symbols.  */
3467   if (elf_bad_symtab (abfd))
3468     {
3469       extsymcount = symcount;
3470       extsymoff = 0;
3471     }
3472   else
3473     {
3474       extsymcount = symcount - hdr->sh_info;
3475       extsymoff = hdr->sh_info;
3476     }
3477 
3478   if (extsymcount == 0)
3479     return false;
3480 
3481   /* Read in the symbol table.  */
3482   isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3483 				  NULL, NULL, NULL);
3484   if (isymbuf == NULL)
3485     return false;
3486 
3487   /* Scan the symbol table looking for SYMDEF.  */
3488   result = false;
3489   for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
3490     {
3491       const char *name;
3492 
3493       name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3494 					      isym->st_name);
3495       if (name == NULL)
3496 	break;
3497 
3498       if (strcmp (name, symdef->name) == 0)
3499 	{
3500 	  result = is_global_data_symbol_definition (abfd, isym);
3501 	  break;
3502 	}
3503     }
3504 
3505   free (isymbuf);
3506 
3507   return result;
3508 }
3509 
3510 /* Add an entry to the .dynamic table.  */
3511 
3512 bool
_bfd_elf_add_dynamic_entry(struct bfd_link_info * info,bfd_vma tag,bfd_vma val)3513 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
3514 			    bfd_vma tag,
3515 			    bfd_vma val)
3516 {
3517   struct elf_link_hash_table *hash_table;
3518   const struct elf_backend_data *bed;
3519   asection *s;
3520   bfd_size_type newsize;
3521   bfd_byte *newcontents;
3522   Elf_Internal_Dyn dyn;
3523 
3524   hash_table = elf_hash_table (info);
3525   if (! is_elf_hash_table (&hash_table->root))
3526     return false;
3527 
3528   if (tag == DT_RELA || tag == DT_REL)
3529     hash_table->dynamic_relocs = true;
3530 
3531   bed = get_elf_backend_data (hash_table->dynobj);
3532   s = bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3533   BFD_ASSERT (s != NULL);
3534 
3535   newsize = s->size + bed->s->sizeof_dyn;
3536   newcontents = (bfd_byte *) bfd_realloc (s->contents, newsize);
3537   if (newcontents == NULL)
3538     return false;
3539 
3540   dyn.d_tag = tag;
3541   dyn.d_un.d_val = val;
3542   bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
3543 
3544   s->size = newsize;
3545   s->contents = newcontents;
3546 
3547   return true;
3548 }
3549 
3550 /* Strip zero-sized dynamic sections.  */
3551 
3552 bool
_bfd_elf_strip_zero_sized_dynamic_sections(struct bfd_link_info * info)3553 _bfd_elf_strip_zero_sized_dynamic_sections (struct bfd_link_info *info)
3554 {
3555   struct elf_link_hash_table *hash_table;
3556   const struct elf_backend_data *bed;
3557   asection *s, *sdynamic, **pp;
3558   asection *rela_dyn, *rel_dyn;
3559   Elf_Internal_Dyn dyn;
3560   bfd_byte *extdyn, *next;
3561   void (*swap_dyn_in) (bfd *, const void *, Elf_Internal_Dyn *);
3562   bool strip_zero_sized;
3563   bool strip_zero_sized_plt;
3564 
3565   if (bfd_link_relocatable (info))
3566     return true;
3567 
3568   hash_table = elf_hash_table (info);
3569   if (!is_elf_hash_table (&hash_table->root))
3570     return false;
3571 
3572   if (!hash_table->dynobj)
3573     return true;
3574 
3575   sdynamic= bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3576   if (!sdynamic)
3577     return true;
3578 
3579   bed = get_elf_backend_data (hash_table->dynobj);
3580   swap_dyn_in = bed->s->swap_dyn_in;
3581 
3582   strip_zero_sized = false;
3583   strip_zero_sized_plt = false;
3584 
3585   /* Strip zero-sized dynamic sections.  */
3586   rela_dyn = bfd_get_section_by_name (info->output_bfd, ".rela.dyn");
3587   rel_dyn = bfd_get_section_by_name (info->output_bfd, ".rel.dyn");
3588   for (pp = &info->output_bfd->sections; (s = *pp) != NULL;)
3589     if (s->size == 0
3590 	&& (s == rela_dyn
3591 	    || s == rel_dyn
3592 	    || s == hash_table->srelplt->output_section
3593 	    || s == hash_table->splt->output_section))
3594       {
3595 	*pp = s->next;
3596 	info->output_bfd->section_count--;
3597 	strip_zero_sized = true;
3598 	if (s == rela_dyn)
3599 	  s = rela_dyn;
3600 	if (s == rel_dyn)
3601 	  s = rel_dyn;
3602 	else if (s == hash_table->splt->output_section)
3603 	  {
3604 	    s = hash_table->splt;
3605 	    strip_zero_sized_plt = true;
3606 	  }
3607 	else
3608 	  s = hash_table->srelplt;
3609 	s->flags |= SEC_EXCLUDE;
3610 	s->output_section = bfd_abs_section_ptr;
3611       }
3612     else
3613       pp = &s->next;
3614 
3615   if (strip_zero_sized_plt)
3616     for (extdyn = sdynamic->contents;
3617 	 extdyn < sdynamic->contents + sdynamic->size;
3618 	 extdyn = next)
3619       {
3620 	next = extdyn + bed->s->sizeof_dyn;
3621 	swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3622 	switch (dyn.d_tag)
3623 	  {
3624 	  default:
3625 	    break;
3626 	  case DT_JMPREL:
3627 	  case DT_PLTRELSZ:
3628 	  case DT_PLTREL:
3629 	    /* Strip DT_PLTRELSZ, DT_JMPREL and DT_PLTREL entries if
3630 	       the procedure linkage table (the .plt section) has been
3631 	       removed.  */
3632 	    memmove (extdyn, next,
3633 		     sdynamic->size - (next - sdynamic->contents));
3634 	    next = extdyn;
3635 	  }
3636       }
3637 
3638   if (strip_zero_sized)
3639     {
3640       /* Regenerate program headers.  */
3641       elf_seg_map (info->output_bfd) = NULL;
3642       return _bfd_elf_map_sections_to_segments (info->output_bfd, info);
3643     }
3644 
3645   return true;
3646 }
3647 
3648 /* Add a DT_NEEDED entry for this dynamic object.  Returns -1 on error,
3649    1 if a DT_NEEDED tag already exists, and 0 on success.  */
3650 
3651 int
bfd_elf_add_dt_needed_tag(bfd * abfd,struct bfd_link_info * info)3652 bfd_elf_add_dt_needed_tag (bfd *abfd, struct bfd_link_info *info)
3653 {
3654   struct elf_link_hash_table *hash_table;
3655   size_t strindex;
3656   const char *soname;
3657 
3658   if (!_bfd_elf_link_create_dynstrtab (abfd, info))
3659     return -1;
3660 
3661   hash_table = elf_hash_table (info);
3662   soname = elf_dt_name (abfd);
3663   strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, false);
3664   if (strindex == (size_t) -1)
3665     return -1;
3666 
3667   if (_bfd_elf_strtab_refcount (hash_table->dynstr, strindex) != 1)
3668     {
3669       asection *sdyn;
3670       const struct elf_backend_data *bed;
3671       bfd_byte *extdyn;
3672 
3673       bed = get_elf_backend_data (hash_table->dynobj);
3674       sdyn = bfd_get_linker_section (hash_table->dynobj, ".dynamic");
3675       if (sdyn != NULL)
3676 	for (extdyn = sdyn->contents;
3677 	     extdyn < sdyn->contents + sdyn->size;
3678 	     extdyn += bed->s->sizeof_dyn)
3679 	  {
3680 	    Elf_Internal_Dyn dyn;
3681 
3682 	    bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
3683 	    if (dyn.d_tag == DT_NEEDED
3684 		&& dyn.d_un.d_val == strindex)
3685 	      {
3686 		_bfd_elf_strtab_delref (hash_table->dynstr, strindex);
3687 		return 1;
3688 	      }
3689 	  }
3690     }
3691 
3692   if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
3693     return -1;
3694 
3695   if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
3696     return -1;
3697 
3698   return 0;
3699 }
3700 
3701 /* Return true if SONAME is on the needed list between NEEDED and STOP
3702    (or the end of list if STOP is NULL), and needed by a library that
3703    will be loaded.  */
3704 
3705 static bool
on_needed_list(const char * soname,struct bfd_link_needed_list * needed,struct bfd_link_needed_list * stop)3706 on_needed_list (const char *soname,
3707 		struct bfd_link_needed_list *needed,
3708 		struct bfd_link_needed_list *stop)
3709 {
3710   struct bfd_link_needed_list *look;
3711   for (look = needed; look != stop; look = look->next)
3712     if (strcmp (soname, look->name) == 0
3713 	&& ((elf_dyn_lib_class (look->by) & DYN_AS_NEEDED) == 0
3714 	    /* If needed by a library that itself is not directly
3715 	       needed, recursively check whether that library is
3716 	       indirectly needed.  Since we add DT_NEEDED entries to
3717 	       the end of the list, library dependencies appear after
3718 	       the library.  Therefore search prior to the current
3719 	       LOOK, preventing possible infinite recursion.  */
3720 	    || on_needed_list (elf_dt_name (look->by), needed, look)))
3721       return true;
3722 
3723   return false;
3724 }
3725 
3726 /* Sort symbol by value, section, size, and type.  */
3727 static int
elf_sort_symbol(const void * arg1,const void * arg2)3728 elf_sort_symbol (const void *arg1, const void *arg2)
3729 {
3730   const struct elf_link_hash_entry *h1;
3731   const struct elf_link_hash_entry *h2;
3732   bfd_signed_vma vdiff;
3733   int sdiff;
3734   const char *n1;
3735   const char *n2;
3736 
3737   h1 = *(const struct elf_link_hash_entry **) arg1;
3738   h2 = *(const struct elf_link_hash_entry **) arg2;
3739   vdiff = h1->root.u.def.value - h2->root.u.def.value;
3740   if (vdiff != 0)
3741     return vdiff > 0 ? 1 : -1;
3742 
3743   sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
3744   if (sdiff != 0)
3745     return sdiff;
3746 
3747   /* Sort so that sized symbols are selected over zero size symbols.  */
3748   vdiff = h1->size - h2->size;
3749   if (vdiff != 0)
3750     return vdiff > 0 ? 1 : -1;
3751 
3752   /* Sort so that STT_OBJECT is selected over STT_NOTYPE.  */
3753   if (h1->type != h2->type)
3754     return h1->type - h2->type;
3755 
3756   /* If symbols are properly sized and typed, and multiple strong
3757      aliases are not defined in a shared library by the user we
3758      shouldn't get here.  Unfortunately linker script symbols like
3759      __bss_start sometimes match a user symbol defined at the start of
3760      .bss without proper size and type.  We'd like to preference the
3761      user symbol over reserved system symbols.  Sort on leading
3762      underscores.  */
3763   n1 = h1->root.root.string;
3764   n2 = h2->root.root.string;
3765   while (*n1 == *n2)
3766     {
3767       if (*n1 == 0)
3768 	break;
3769       ++n1;
3770       ++n2;
3771     }
3772   if (*n1 == '_')
3773     return -1;
3774   if (*n2 == '_')
3775     return 1;
3776 
3777   /* Final sort on name selects user symbols like '_u' over reserved
3778      system symbols like '_Z' and also will avoid qsort instability.  */
3779   return *n1 - *n2;
3780 }
3781 
3782 /* This function is used to adjust offsets into .dynstr for
3783    dynamic symbols.  This is called via elf_link_hash_traverse.  */
3784 
3785 static bool
elf_adjust_dynstr_offsets(struct elf_link_hash_entry * h,void * data)3786 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
3787 {
3788   struct elf_strtab_hash *dynstr = (struct elf_strtab_hash *) data;
3789 
3790   if (h->dynindx != -1)
3791     h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
3792   return true;
3793 }
3794 
3795 /* Assign string offsets in .dynstr, update all structures referencing
3796    them.  */
3797 
3798 static bool
elf_finalize_dynstr(bfd * output_bfd,struct bfd_link_info * info)3799 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
3800 {
3801   struct elf_link_hash_table *hash_table = elf_hash_table (info);
3802   struct elf_link_local_dynamic_entry *entry;
3803   struct elf_strtab_hash *dynstr = hash_table->dynstr;
3804   bfd *dynobj = hash_table->dynobj;
3805   asection *sdyn;
3806   bfd_size_type size;
3807   const struct elf_backend_data *bed;
3808   bfd_byte *extdyn;
3809 
3810   _bfd_elf_strtab_finalize (dynstr);
3811   size = _bfd_elf_strtab_size (dynstr);
3812 
3813   /* Allow the linker to examine the dynsymtab now it's fully populated.  */
3814 
3815   if (info->callbacks->examine_strtab)
3816     info->callbacks->examine_strtab (dynstr);
3817 
3818   bed = get_elf_backend_data (dynobj);
3819   sdyn = bfd_get_linker_section (dynobj, ".dynamic");
3820   BFD_ASSERT (sdyn != NULL);
3821 
3822   /* Update all .dynamic entries referencing .dynstr strings.  */
3823   for (extdyn = sdyn->contents;
3824        extdyn < sdyn->contents + sdyn->size;
3825        extdyn += bed->s->sizeof_dyn)
3826     {
3827       Elf_Internal_Dyn dyn;
3828 
3829       bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
3830       switch (dyn.d_tag)
3831 	{
3832 	case DT_STRSZ:
3833 	  dyn.d_un.d_val = size;
3834 	  break;
3835 	case DT_NEEDED:
3836 	case DT_SONAME:
3837 	case DT_RPATH:
3838 	case DT_RUNPATH:
3839 	case DT_FILTER:
3840 	case DT_AUXILIARY:
3841 	case DT_AUDIT:
3842 	case DT_DEPAUDIT:
3843 	  dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
3844 	  break;
3845 	default:
3846 	  continue;
3847 	}
3848       bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
3849     }
3850 
3851   /* Now update local dynamic symbols.  */
3852   for (entry = hash_table->dynlocal; entry ; entry = entry->next)
3853     entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
3854 						  entry->isym.st_name);
3855 
3856   /* And the rest of dynamic symbols.  */
3857   elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
3858 
3859   /* Adjust version definitions.  */
3860   if (elf_tdata (output_bfd)->cverdefs)
3861     {
3862       asection *s;
3863       bfd_byte *p;
3864       size_t i;
3865       Elf_Internal_Verdef def;
3866       Elf_Internal_Verdaux defaux;
3867 
3868       s = bfd_get_linker_section (dynobj, ".gnu.version_d");
3869       p = s->contents;
3870       do
3871 	{
3872 	  _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3873 				   &def);
3874 	  p += sizeof (Elf_External_Verdef);
3875 	  if (def.vd_aux != sizeof (Elf_External_Verdef))
3876 	    continue;
3877 	  for (i = 0; i < def.vd_cnt; ++i)
3878 	    {
3879 	      _bfd_elf_swap_verdaux_in (output_bfd,
3880 					(Elf_External_Verdaux *) p, &defaux);
3881 	      defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3882 							defaux.vda_name);
3883 	      _bfd_elf_swap_verdaux_out (output_bfd,
3884 					 &defaux, (Elf_External_Verdaux *) p);
3885 	      p += sizeof (Elf_External_Verdaux);
3886 	    }
3887 	}
3888       while (def.vd_next);
3889     }
3890 
3891   /* Adjust version references.  */
3892   if (elf_tdata (output_bfd)->verref)
3893     {
3894       asection *s;
3895       bfd_byte *p;
3896       size_t i;
3897       Elf_Internal_Verneed need;
3898       Elf_Internal_Vernaux needaux;
3899 
3900       s = bfd_get_linker_section (dynobj, ".gnu.version_r");
3901       p = s->contents;
3902       do
3903 	{
3904 	  _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3905 				    &need);
3906 	  need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3907 	  _bfd_elf_swap_verneed_out (output_bfd, &need,
3908 				     (Elf_External_Verneed *) p);
3909 	  p += sizeof (Elf_External_Verneed);
3910 	  for (i = 0; i < need.vn_cnt; ++i)
3911 	    {
3912 	      _bfd_elf_swap_vernaux_in (output_bfd,
3913 					(Elf_External_Vernaux *) p, &needaux);
3914 	      needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3915 							 needaux.vna_name);
3916 	      _bfd_elf_swap_vernaux_out (output_bfd,
3917 					 &needaux,
3918 					 (Elf_External_Vernaux *) p);
3919 	      p += sizeof (Elf_External_Vernaux);
3920 	    }
3921 	}
3922       while (need.vn_next);
3923     }
3924 
3925   return true;
3926 }
3927 
3928 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3929    The default is to only match when the INPUT and OUTPUT are exactly
3930    the same target.  */
3931 
3932 bool
_bfd_elf_default_relocs_compatible(const bfd_target * input,const bfd_target * output)3933 _bfd_elf_default_relocs_compatible (const bfd_target *input,
3934 				    const bfd_target *output)
3935 {
3936   return input == output;
3937 }
3938 
3939 /* Return TRUE iff relocations for INPUT are compatible with OUTPUT.
3940    This version is used when different targets for the same architecture
3941    are virtually identical.  */
3942 
3943 bool
_bfd_elf_relocs_compatible(const bfd_target * input,const bfd_target * output)3944 _bfd_elf_relocs_compatible (const bfd_target *input,
3945 			    const bfd_target *output)
3946 {
3947   const struct elf_backend_data *obed, *ibed;
3948 
3949   if (input == output)
3950     return true;
3951 
3952   ibed = xvec_get_elf_backend_data (input);
3953   obed = xvec_get_elf_backend_data (output);
3954 
3955   if (ibed->arch != obed->arch)
3956     return false;
3957 
3958   /* If both backends are using this function, deem them compatible.  */
3959   return ibed->relocs_compatible == obed->relocs_compatible;
3960 }
3961 
3962 /* Make a special call to the linker "notice" function to tell it that
3963    we are about to handle an as-needed lib, or have finished
3964    processing the lib.  */
3965 
3966 bool
_bfd_elf_notice_as_needed(bfd * ibfd,struct bfd_link_info * info,enum notice_asneeded_action act)3967 _bfd_elf_notice_as_needed (bfd *ibfd,
3968 			   struct bfd_link_info *info,
3969 			   enum notice_asneeded_action act)
3970 {
3971   return (*info->callbacks->notice) (info, NULL, NULL, ibfd, NULL, act, 0);
3972 }
3973 
3974 /* Check relocations an ELF object file.  */
3975 
3976 bool
_bfd_elf_link_check_relocs(bfd * abfd,struct bfd_link_info * info)3977 _bfd_elf_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
3978 {
3979   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
3980   struct elf_link_hash_table *htab = elf_hash_table (info);
3981 
3982   /* If this object is the same format as the output object, and it is
3983      not a shared library, then let the backend look through the
3984      relocs.
3985 
3986      This is required to build global offset table entries and to
3987      arrange for dynamic relocs.  It is not required for the
3988      particular common case of linking non PIC code, even when linking
3989      against shared libraries, but unfortunately there is no way of
3990      knowing whether an object file has been compiled PIC or not.
3991      Looking through the relocs is not particularly time consuming.
3992      The problem is that we must either (1) keep the relocs in memory,
3993      which causes the linker to require additional runtime memory or
3994      (2) read the relocs twice from the input file, which wastes time.
3995      This would be a good case for using mmap.
3996 
3997      I have no idea how to handle linking PIC code into a file of a
3998      different format.  It probably can't be done.  */
3999   if ((abfd->flags & DYNAMIC) == 0
4000       && is_elf_hash_table (&htab->root)
4001       && bed->check_relocs != NULL
4002       && elf_object_id (abfd) == elf_hash_table_id (htab)
4003       && (*bed->relocs_compatible) (abfd->xvec, info->output_bfd->xvec))
4004     {
4005       asection *o;
4006 
4007       for (o = abfd->sections; o != NULL; o = o->next)
4008 	{
4009 	  Elf_Internal_Rela *internal_relocs;
4010 	  bool ok;
4011 
4012 	  /* Don't check relocations in excluded sections.  Don't do
4013 	     anything special with non-loaded, non-alloced sections.
4014 	     In particular, any relocs in such sections should not
4015 	     affect GOT and PLT reference counting (ie.  we don't
4016 	     allow them to create GOT or PLT entries), there's no
4017 	     possibility or desire to optimize TLS relocs, and
4018 	     there's not much point in propagating relocs to shared
4019 	     libs that the dynamic linker won't relocate.  */
4020 	  if ((o->flags & SEC_ALLOC) == 0
4021 	      || (o->flags & SEC_RELOC) == 0
4022 	      || (o->flags & SEC_EXCLUDE) != 0
4023 	      || o->reloc_count == 0
4024 	      || ((info->strip == strip_all || info->strip == strip_debugger)
4025 		  && (o->flags & SEC_DEBUGGING) != 0)
4026 	      || bfd_is_abs_section (o->output_section))
4027 	    continue;
4028 
4029 	  internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4030 						       info->keep_memory);
4031 	  if (internal_relocs == NULL)
4032 	    return false;
4033 
4034 	  ok = (*bed->check_relocs) (abfd, info, o, internal_relocs);
4035 
4036 	  if (elf_section_data (o)->relocs != internal_relocs)
4037 	    free (internal_relocs);
4038 
4039 	  if (! ok)
4040 	    return false;
4041 	}
4042     }
4043 
4044   return true;
4045 }
4046 
4047 /* Add symbols from an ELF object file to the linker hash table.  */
4048 
4049 static bool
elf_link_add_object_symbols(bfd * abfd,struct bfd_link_info * info)4050 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
4051 {
4052   Elf_Internal_Ehdr *ehdr;
4053   Elf_Internal_Shdr *hdr;
4054   size_t symcount;
4055   size_t extsymcount;
4056   size_t extsymoff;
4057   struct elf_link_hash_entry **sym_hash;
4058   bool dynamic;
4059   Elf_External_Versym *extversym = NULL;
4060   Elf_External_Versym *extversym_end = NULL;
4061   Elf_External_Versym *ever;
4062   struct elf_link_hash_entry *weaks;
4063   struct elf_link_hash_entry **nondeflt_vers = NULL;
4064   size_t nondeflt_vers_cnt = 0;
4065   Elf_Internal_Sym *isymbuf = NULL;
4066   Elf_Internal_Sym *isym;
4067   Elf_Internal_Sym *isymend;
4068   const struct elf_backend_data *bed;
4069   bool add_needed;
4070   struct elf_link_hash_table *htab;
4071   void *alloc_mark = NULL;
4072   struct bfd_hash_entry **old_table = NULL;
4073   unsigned int old_size = 0;
4074   unsigned int old_count = 0;
4075   void *old_tab = NULL;
4076   void *old_ent;
4077   struct bfd_link_hash_entry *old_undefs = NULL;
4078   struct bfd_link_hash_entry *old_undefs_tail = NULL;
4079   void *old_strtab = NULL;
4080   size_t tabsize = 0;
4081   asection *s;
4082   bool just_syms;
4083 
4084   htab = elf_hash_table (info);
4085   bed = get_elf_backend_data (abfd);
4086 
4087   if ((abfd->flags & DYNAMIC) == 0)
4088     dynamic = false;
4089   else
4090     {
4091       dynamic = true;
4092 
4093       /* You can't use -r against a dynamic object.  Also, there's no
4094 	 hope of using a dynamic object which does not exactly match
4095 	 the format of the output file.  */
4096       if (bfd_link_relocatable (info)
4097 	  || !is_elf_hash_table (&htab->root)
4098 	  || info->output_bfd->xvec != abfd->xvec)
4099 	{
4100 	  if (bfd_link_relocatable (info))
4101 	    bfd_set_error (bfd_error_invalid_operation);
4102 	  else
4103 	    bfd_set_error (bfd_error_wrong_format);
4104 	  goto error_return;
4105 	}
4106     }
4107 
4108   ehdr = elf_elfheader (abfd);
4109   if (info->warn_alternate_em
4110       && bed->elf_machine_code != ehdr->e_machine
4111       && ((bed->elf_machine_alt1 != 0
4112 	   && ehdr->e_machine == bed->elf_machine_alt1)
4113 	  || (bed->elf_machine_alt2 != 0
4114 	      && ehdr->e_machine == bed->elf_machine_alt2)))
4115     _bfd_error_handler
4116       /* xgettext:c-format */
4117       (_("alternate ELF machine code found (%d) in %pB, expecting %d"),
4118        ehdr->e_machine, abfd, bed->elf_machine_code);
4119 
4120   /* As a GNU extension, any input sections which are named
4121      .gnu.warning.SYMBOL are treated as warning symbols for the given
4122      symbol.  This differs from .gnu.warning sections, which generate
4123      warnings when they are included in an output file.  */
4124   /* PR 12761: Also generate this warning when building shared libraries.  */
4125   for (s = abfd->sections; s != NULL; s = s->next)
4126     {
4127       const char *name;
4128 
4129       name = bfd_section_name (s);
4130       if (startswith (name, ".gnu.warning."))
4131 	{
4132 	  char *msg;
4133 	  bfd_size_type sz;
4134 
4135 	  name += sizeof ".gnu.warning." - 1;
4136 
4137 	  /* If this is a shared object, then look up the symbol
4138 	     in the hash table.  If it is there, and it is already
4139 	     been defined, then we will not be using the entry
4140 	     from this shared object, so we don't need to warn.
4141 	     FIXME: If we see the definition in a regular object
4142 	     later on, we will warn, but we shouldn't.  The only
4143 	     fix is to keep track of what warnings we are supposed
4144 	     to emit, and then handle them all at the end of the
4145 	     link.  */
4146 	  if (dynamic)
4147 	    {
4148 	      struct elf_link_hash_entry *h;
4149 
4150 	      h = elf_link_hash_lookup (htab, name, false, false, true);
4151 
4152 	      /* FIXME: What about bfd_link_hash_common?  */
4153 	      if (h != NULL
4154 		  && (h->root.type == bfd_link_hash_defined
4155 		      || h->root.type == bfd_link_hash_defweak))
4156 		continue;
4157 	    }
4158 
4159 	  sz = s->size;
4160 	  msg = (char *) bfd_alloc (abfd, sz + 1);
4161 	  if (msg == NULL)
4162 	    goto error_return;
4163 
4164 	  if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
4165 	    goto error_return;
4166 
4167 	  msg[sz] = '\0';
4168 
4169 	  if (! (_bfd_generic_link_add_one_symbol
4170 		 (info, abfd, name, BSF_WARNING, s, 0, msg,
4171 		  false, bed->collect, NULL)))
4172 	    goto error_return;
4173 
4174 	  if (bfd_link_executable (info))
4175 	    {
4176 	      /* Clobber the section size so that the warning does
4177 		 not get copied into the output file.  */
4178 	      s->size = 0;
4179 
4180 	      /* Also set SEC_EXCLUDE, so that symbols defined in
4181 		 the warning section don't get copied to the output.  */
4182 	      s->flags |= SEC_EXCLUDE;
4183 	    }
4184 	}
4185     }
4186 
4187   just_syms = ((s = abfd->sections) != NULL
4188 	       && s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS);
4189 
4190   add_needed = true;
4191   if (! dynamic)
4192     {
4193       /* If we are creating a shared library, create all the dynamic
4194 	 sections immediately.  We need to attach them to something,
4195 	 so we attach them to this BFD, provided it is the right
4196 	 format and is not from ld --just-symbols.  Always create the
4197 	 dynamic sections for -E/--dynamic-list.  FIXME: If there
4198 	 are no input BFD's of the same format as the output, we can't
4199 	 make a shared library.  */
4200       if (!just_syms
4201 	  && (bfd_link_pic (info)
4202 	      || (!bfd_link_relocatable (info)
4203 		  && info->nointerp
4204 		  && (info->export_dynamic || info->dynamic)))
4205 	  && is_elf_hash_table (&htab->root)
4206 	  && info->output_bfd->xvec == abfd->xvec
4207 	  && !htab->dynamic_sections_created)
4208 	{
4209 	  if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
4210 	    goto error_return;
4211 	}
4212     }
4213   else if (!is_elf_hash_table (&htab->root))
4214     goto error_return;
4215   else
4216     {
4217       const char *soname = NULL;
4218       char *audit = NULL;
4219       struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
4220       const Elf_Internal_Phdr *phdr;
4221       struct elf_link_loaded_list *loaded_lib;
4222 
4223       /* ld --just-symbols and dynamic objects don't mix very well.
4224 	 ld shouldn't allow it.  */
4225       if (just_syms)
4226 	abort ();
4227 
4228       /* If this dynamic lib was specified on the command line with
4229 	 --as-needed in effect, then we don't want to add a DT_NEEDED
4230 	 tag unless the lib is actually used.  Similary for libs brought
4231 	 in by another lib's DT_NEEDED.  When --no-add-needed is used
4232 	 on a dynamic lib, we don't want to add a DT_NEEDED entry for
4233 	 any dynamic library in DT_NEEDED tags in the dynamic lib at
4234 	 all.  */
4235       add_needed = (elf_dyn_lib_class (abfd)
4236 		    & (DYN_AS_NEEDED | DYN_DT_NEEDED
4237 		       | DYN_NO_NEEDED)) == 0;
4238 
4239       s = bfd_get_section_by_name (abfd, ".dynamic");
4240       if (s != NULL)
4241 	{
4242 	  bfd_byte *dynbuf;
4243 	  bfd_byte *extdyn;
4244 	  unsigned int elfsec;
4245 	  unsigned long shlink;
4246 
4247 	  if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
4248 	    {
4249 	    error_free_dyn:
4250 	      free (dynbuf);
4251 	      goto error_return;
4252 	    }
4253 
4254 	  elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
4255 	  if (elfsec == SHN_BAD)
4256 	    goto error_free_dyn;
4257 	  shlink = elf_elfsections (abfd)[elfsec]->sh_link;
4258 
4259 	  for (extdyn = dynbuf;
4260 	       extdyn <= dynbuf + s->size - bed->s->sizeof_dyn;
4261 	       extdyn += bed->s->sizeof_dyn)
4262 	    {
4263 	      Elf_Internal_Dyn dyn;
4264 
4265 	      bed->s->swap_dyn_in (abfd, extdyn, &dyn);
4266 	      if (dyn.d_tag == DT_SONAME)
4267 		{
4268 		  unsigned int tagv = dyn.d_un.d_val;
4269 		  soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4270 		  if (soname == NULL)
4271 		    goto error_free_dyn;
4272 		}
4273 	      if (dyn.d_tag == DT_NEEDED)
4274 		{
4275 		  struct bfd_link_needed_list *n, **pn;
4276 		  char *fnm, *anm;
4277 		  unsigned int tagv = dyn.d_un.d_val;
4278 		  size_t amt = sizeof (struct bfd_link_needed_list);
4279 
4280 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4281 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4282 		  if (n == NULL || fnm == NULL)
4283 		    goto error_free_dyn;
4284 		  amt = strlen (fnm) + 1;
4285 		  anm = (char *) bfd_alloc (abfd, amt);
4286 		  if (anm == NULL)
4287 		    goto error_free_dyn;
4288 		  memcpy (anm, fnm, amt);
4289 		  n->name = anm;
4290 		  n->by = abfd;
4291 		  n->next = NULL;
4292 		  for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
4293 		    ;
4294 		  *pn = n;
4295 		}
4296 	      if (dyn.d_tag == DT_RUNPATH)
4297 		{
4298 		  struct bfd_link_needed_list *n, **pn;
4299 		  char *fnm, *anm;
4300 		  unsigned int tagv = dyn.d_un.d_val;
4301 		  size_t amt = sizeof (struct bfd_link_needed_list);
4302 
4303 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4304 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4305 		  if (n == NULL || fnm == NULL)
4306 		    goto error_free_dyn;
4307 		  amt = strlen (fnm) + 1;
4308 		  anm = (char *) bfd_alloc (abfd, amt);
4309 		  if (anm == NULL)
4310 		    goto error_free_dyn;
4311 		  memcpy (anm, fnm, amt);
4312 		  n->name = anm;
4313 		  n->by = abfd;
4314 		  n->next = NULL;
4315 		  for (pn = & runpath;
4316 		       *pn != NULL;
4317 		       pn = &(*pn)->next)
4318 		    ;
4319 		  *pn = n;
4320 		}
4321 	      /* Ignore DT_RPATH if we have seen DT_RUNPATH.  */
4322 	      if (!runpath && dyn.d_tag == DT_RPATH)
4323 		{
4324 		  struct bfd_link_needed_list *n, **pn;
4325 		  char *fnm, *anm;
4326 		  unsigned int tagv = dyn.d_un.d_val;
4327 		  size_t amt = sizeof (struct bfd_link_needed_list);
4328 
4329 		  n = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
4330 		  fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4331 		  if (n == NULL || fnm == NULL)
4332 		    goto error_free_dyn;
4333 		  amt = strlen (fnm) + 1;
4334 		  anm = (char *) bfd_alloc (abfd, amt);
4335 		  if (anm == NULL)
4336 		    goto error_free_dyn;
4337 		  memcpy (anm, fnm, amt);
4338 		  n->name = anm;
4339 		  n->by = abfd;
4340 		  n->next = NULL;
4341 		  for (pn = & rpath;
4342 		       *pn != NULL;
4343 		       pn = &(*pn)->next)
4344 		    ;
4345 		  *pn = n;
4346 		}
4347 	      if (dyn.d_tag == DT_AUDIT)
4348 		{
4349 		  unsigned int tagv = dyn.d_un.d_val;
4350 		  audit = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
4351 		}
4352 	      if (dyn.d_tag == DT_FLAGS_1)
4353 		elf_tdata (abfd)->is_pie = (dyn.d_un.d_val & DF_1_PIE) != 0;
4354 	    }
4355 
4356 	  free (dynbuf);
4357 	}
4358 
4359       /* DT_RUNPATH overrides DT_RPATH.  Do _NOT_ bfd_release, as that
4360 	 frees all more recently bfd_alloc'd blocks as well.  */
4361       if (runpath)
4362 	rpath = runpath;
4363 
4364       if (rpath)
4365 	{
4366 	  struct bfd_link_needed_list **pn;
4367 	  for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
4368 	    ;
4369 	  *pn = rpath;
4370 	}
4371 
4372       /* If we have a PT_GNU_RELRO program header, mark as read-only
4373 	 all sections contained fully therein.  This makes relro
4374 	 shared library sections appear as they will at run-time.  */
4375       phdr = elf_tdata (abfd)->phdr + elf_elfheader (abfd)->e_phnum;
4376       while (phdr-- > elf_tdata (abfd)->phdr)
4377 	if (phdr->p_type == PT_GNU_RELRO)
4378 	  {
4379 	    for (s = abfd->sections; s != NULL; s = s->next)
4380 	      {
4381 		unsigned int opb = bfd_octets_per_byte (abfd, s);
4382 
4383 		if ((s->flags & SEC_ALLOC) != 0
4384 		    && s->vma * opb >= phdr->p_vaddr
4385 		    && s->vma * opb + s->size <= phdr->p_vaddr + phdr->p_memsz)
4386 		  s->flags |= SEC_READONLY;
4387 	      }
4388 	    break;
4389 	  }
4390 
4391       /* We do not want to include any of the sections in a dynamic
4392 	 object in the output file.  We hack by simply clobbering the
4393 	 list of sections in the BFD.  This could be handled more
4394 	 cleanly by, say, a new section flag; the existing
4395 	 SEC_NEVER_LOAD flag is not the one we want, because that one
4396 	 still implies that the section takes up space in the output
4397 	 file.  */
4398       bfd_section_list_clear (abfd);
4399 
4400       /* Find the name to use in a DT_NEEDED entry that refers to this
4401 	 object.  If the object has a DT_SONAME entry, we use it.
4402 	 Otherwise, if the generic linker stuck something in
4403 	 elf_dt_name, we use that.  Otherwise, we just use the file
4404 	 name.  */
4405       if (soname == NULL || *soname == '\0')
4406 	{
4407 	  soname = elf_dt_name (abfd);
4408 	  if (soname == NULL || *soname == '\0')
4409 	    soname = bfd_get_filename (abfd);
4410 	}
4411 
4412       /* Save the SONAME because sometimes the linker emulation code
4413 	 will need to know it.  */
4414       elf_dt_name (abfd) = soname;
4415 
4416       /* If we have already included this dynamic object in the
4417 	 link, just ignore it.  There is no reason to include a
4418 	 particular dynamic object more than once.  */
4419       for (loaded_lib = htab->dyn_loaded;
4420 	   loaded_lib != NULL;
4421 	   loaded_lib = loaded_lib->next)
4422 	{
4423 	  if (strcmp (elf_dt_name (loaded_lib->abfd), soname) == 0)
4424 	    return true;
4425 	}
4426 
4427       /* Create dynamic sections for backends that require that be done
4428 	 before setup_gnu_properties.  */
4429       if (add_needed
4430 	  && !_bfd_elf_link_create_dynamic_sections (abfd, info))
4431 	return false;
4432 
4433       /* Save the DT_AUDIT entry for the linker emulation code. */
4434       elf_dt_audit (abfd) = audit;
4435     }
4436 
4437   /* If this is a dynamic object, we always link against the .dynsym
4438      symbol table, not the .symtab symbol table.  The dynamic linker
4439      will only see the .dynsym symbol table, so there is no reason to
4440      look at .symtab for a dynamic object.  */
4441 
4442   if (! dynamic || elf_dynsymtab (abfd) == 0)
4443     hdr = &elf_tdata (abfd)->symtab_hdr;
4444   else
4445     hdr = &elf_tdata (abfd)->dynsymtab_hdr;
4446 
4447   symcount = hdr->sh_size / bed->s->sizeof_sym;
4448 
4449   /* The sh_info field of the symtab header tells us where the
4450      external symbols start.  We don't care about the local symbols at
4451      this point.  */
4452   if (elf_bad_symtab (abfd))
4453     {
4454       extsymcount = symcount;
4455       extsymoff = 0;
4456     }
4457   else
4458     {
4459       extsymcount = symcount - hdr->sh_info;
4460       extsymoff = hdr->sh_info;
4461     }
4462 
4463   sym_hash = elf_sym_hashes (abfd);
4464   if (extsymcount != 0)
4465     {
4466       isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
4467 				      NULL, NULL, NULL);
4468       if (isymbuf == NULL)
4469 	goto error_return;
4470 
4471       if (sym_hash == NULL)
4472 	{
4473 	  /* We store a pointer to the hash table entry for each
4474 	     external symbol.  */
4475 	  size_t amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4476 	  sym_hash = (struct elf_link_hash_entry **) bfd_zalloc (abfd, amt);
4477 	  if (sym_hash == NULL)
4478 	    goto error_free_sym;
4479 	  elf_sym_hashes (abfd) = sym_hash;
4480 	}
4481     }
4482 
4483   if (dynamic)
4484     {
4485       /* Read in any version definitions.  */
4486       if (!_bfd_elf_slurp_version_tables (abfd,
4487 					  info->default_imported_symver))
4488 	goto error_free_sym;
4489 
4490       /* Read in the symbol versions, but don't bother to convert them
4491 	 to internal format.  */
4492       if (elf_dynversym (abfd) != 0)
4493 	{
4494 	  Elf_Internal_Shdr *versymhdr = &elf_tdata (abfd)->dynversym_hdr;
4495 	  bfd_size_type amt = versymhdr->sh_size;
4496 
4497 	  if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0)
4498 	    goto error_free_sym;
4499 	  extversym = (Elf_External_Versym *)
4500 	    _bfd_malloc_and_read (abfd, amt, amt);
4501 	  if (extversym == NULL)
4502 	    goto error_free_sym;
4503 	  extversym_end = extversym + amt / sizeof (*extversym);
4504 	}
4505     }
4506 
4507   /* If we are loading an as-needed shared lib, save the symbol table
4508      state before we start adding symbols.  If the lib turns out
4509      to be unneeded, restore the state.  */
4510   if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4511     {
4512       unsigned int i;
4513       size_t entsize;
4514 
4515       for (entsize = 0, i = 0; i < htab->root.table.size; i++)
4516 	{
4517 	  struct bfd_hash_entry *p;
4518 	  struct elf_link_hash_entry *h;
4519 
4520 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4521 	    {
4522 	      h = (struct elf_link_hash_entry *) p;
4523 	      entsize += htab->root.table.entsize;
4524 	      if (h->root.type == bfd_link_hash_warning)
4525 		{
4526 		  entsize += htab->root.table.entsize;
4527 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
4528 		}
4529 	      if (h->root.type == bfd_link_hash_common)
4530 		entsize += sizeof (*h->root.u.c.p);
4531 	    }
4532 	}
4533 
4534       tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
4535       old_tab = bfd_malloc (tabsize + entsize);
4536       if (old_tab == NULL)
4537 	goto error_free_vers;
4538 
4539       /* Remember the current objalloc pointer, so that all mem for
4540 	 symbols added can later be reclaimed.  */
4541       alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
4542       if (alloc_mark == NULL)
4543 	goto error_free_vers;
4544 
4545       /* Make a special call to the linker "notice" function to
4546 	 tell it that we are about to handle an as-needed lib.  */
4547       if (!(*bed->notice_as_needed) (abfd, info, notice_as_needed))
4548 	goto error_free_vers;
4549 
4550       /* Clone the symbol table.  Remember some pointers into the
4551 	 symbol table, and dynamic symbol count.  */
4552       old_ent = (char *) old_tab + tabsize;
4553       memcpy (old_tab, htab->root.table.table, tabsize);
4554       old_undefs = htab->root.undefs;
4555       old_undefs_tail = htab->root.undefs_tail;
4556       old_table = htab->root.table.table;
4557       old_size = htab->root.table.size;
4558       old_count = htab->root.table.count;
4559       old_strtab = NULL;
4560       if (htab->dynstr != NULL)
4561 	{
4562 	  old_strtab = _bfd_elf_strtab_save (htab->dynstr);
4563 	  if (old_strtab == NULL)
4564 	    goto error_free_vers;
4565 	}
4566 
4567       for (i = 0; i < htab->root.table.size; i++)
4568 	{
4569 	  struct bfd_hash_entry *p;
4570 	  struct elf_link_hash_entry *h;
4571 
4572 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4573 	    {
4574 	      h = (struct elf_link_hash_entry *) p;
4575 	      memcpy (old_ent, h, htab->root.table.entsize);
4576 	      old_ent = (char *) old_ent + htab->root.table.entsize;
4577 	      if (h->root.type == bfd_link_hash_warning)
4578 		{
4579 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
4580 		  memcpy (old_ent, h, htab->root.table.entsize);
4581 		  old_ent = (char *) old_ent + htab->root.table.entsize;
4582 		}
4583 	      if (h->root.type == bfd_link_hash_common)
4584 		{
4585 		  memcpy (old_ent, h->root.u.c.p, sizeof (*h->root.u.c.p));
4586 		  old_ent = (char *) old_ent + sizeof (*h->root.u.c.p);
4587 		}
4588 	    }
4589 	}
4590     }
4591 
4592   weaks = NULL;
4593   if (extversym == NULL)
4594     ever = NULL;
4595   else if (extversym + extsymoff < extversym_end)
4596     ever = extversym + extsymoff;
4597   else
4598     {
4599       /* xgettext:c-format */
4600       _bfd_error_handler (_("%pB: invalid version offset %lx (max %lx)"),
4601 			  abfd, (long) extsymoff,
4602 			  (long) (extversym_end - extversym) / sizeof (* extversym));
4603       bfd_set_error (bfd_error_bad_value);
4604       goto error_free_vers;
4605     }
4606 
4607   if (!bfd_link_relocatable (info)
4608       && abfd->lto_slim_object)
4609     {
4610       _bfd_error_handler
4611 	(_("%pB: plugin needed to handle lto object"), abfd);
4612     }
4613 
4614   for (isym = isymbuf, isymend = isymbuf + extsymcount;
4615        isym < isymend;
4616        isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
4617     {
4618       int bind;
4619       bfd_vma value;
4620       asection *sec, *new_sec;
4621       flagword flags;
4622       const char *name;
4623       struct elf_link_hash_entry *h;
4624       struct elf_link_hash_entry *hi;
4625       bool definition;
4626       bool size_change_ok;
4627       bool type_change_ok;
4628       bool new_weak;
4629       bool old_weak;
4630       bfd *override;
4631       bool common;
4632       bool discarded;
4633       unsigned int old_alignment;
4634       unsigned int shindex;
4635       bfd *old_bfd;
4636       bool matched;
4637 
4638       override = NULL;
4639 
4640       flags = BSF_NO_FLAGS;
4641       sec = NULL;
4642       value = isym->st_value;
4643       common = bed->common_definition (isym);
4644       if (common && info->inhibit_common_definition)
4645 	{
4646 	  /* Treat common symbol as undefined for --no-define-common.  */
4647 	  isym->st_shndx = SHN_UNDEF;
4648 	  common = false;
4649 	}
4650       discarded = false;
4651 
4652       bind = ELF_ST_BIND (isym->st_info);
4653       switch (bind)
4654 	{
4655 	case STB_LOCAL:
4656 	  /* This should be impossible, since ELF requires that all
4657 	     global symbols follow all local symbols, and that sh_info
4658 	     point to the first global symbol.  Unfortunately, Irix 5
4659 	     screws this up.  */
4660 	  if (elf_bad_symtab (abfd))
4661 	    continue;
4662 
4663 	  /* If we aren't prepared to handle locals within the globals
4664 	     then we'll likely segfault on a NULL symbol hash if the
4665 	     symbol is ever referenced in relocations.  */
4666 	  shindex = elf_elfheader (abfd)->e_shstrndx;
4667 	  name = bfd_elf_string_from_elf_section (abfd, shindex, hdr->sh_name);
4668 	  _bfd_error_handler (_("%pB: %s local symbol at index %lu"
4669 				" (>= sh_info of %lu)"),
4670 			      abfd, name, (long) (isym - isymbuf + extsymoff),
4671 			      (long) extsymoff);
4672 
4673 	  /* Dynamic object relocations are not processed by ld, so
4674 	     ld won't run into the problem mentioned above.  */
4675 	  if (dynamic)
4676 	    continue;
4677 	  bfd_set_error (bfd_error_bad_value);
4678 	  goto error_free_vers;
4679 
4680 	case STB_GLOBAL:
4681 	  if (isym->st_shndx != SHN_UNDEF && !common)
4682 	    flags = BSF_GLOBAL;
4683 	  break;
4684 
4685 	case STB_WEAK:
4686 	  flags = BSF_WEAK;
4687 	  break;
4688 
4689 	case STB_GNU_UNIQUE:
4690 	  flags = BSF_GNU_UNIQUE;
4691 	  break;
4692 
4693 	default:
4694 	  /* Leave it up to the processor backend.  */
4695 	  break;
4696 	}
4697 
4698       if (isym->st_shndx == SHN_UNDEF)
4699 	sec = bfd_und_section_ptr;
4700       else if (isym->st_shndx == SHN_ABS)
4701 	sec = bfd_abs_section_ptr;
4702       else if (isym->st_shndx == SHN_COMMON)
4703 	{
4704 	  sec = bfd_com_section_ptr;
4705 	  /* What ELF calls the size we call the value.  What ELF
4706 	     calls the value we call the alignment.  */
4707 	  value = isym->st_size;
4708 	}
4709       else
4710 	{
4711 	  sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
4712 	  if (sec == NULL)
4713 	    sec = bfd_abs_section_ptr;
4714 	  else if (discarded_section (sec))
4715 	    {
4716 	      /* Symbols from discarded section are undefined.  We keep
4717 		 its visibility.  */
4718 	      sec = bfd_und_section_ptr;
4719 	      discarded = true;
4720 	      isym->st_shndx = SHN_UNDEF;
4721 	    }
4722 	  else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
4723 	    value -= sec->vma;
4724 	}
4725 
4726       name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
4727 					      isym->st_name);
4728       if (name == NULL)
4729 	goto error_free_vers;
4730 
4731       if (isym->st_shndx == SHN_COMMON
4732 	  && (abfd->flags & BFD_PLUGIN) != 0)
4733 	{
4734 	  asection *xc = bfd_get_section_by_name (abfd, "COMMON");
4735 
4736 	  if (xc == NULL)
4737 	    {
4738 	      flagword sflags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP
4739 				 | SEC_EXCLUDE);
4740 	      xc = bfd_make_section_with_flags (abfd, "COMMON", sflags);
4741 	      if (xc == NULL)
4742 		goto error_free_vers;
4743 	    }
4744 	  sec = xc;
4745 	}
4746       else if (isym->st_shndx == SHN_COMMON
4747 	       && ELF_ST_TYPE (isym->st_info) == STT_TLS
4748 	       && !bfd_link_relocatable (info))
4749 	{
4750 	  asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
4751 
4752 	  if (tcomm == NULL)
4753 	    {
4754 	      flagword sflags = (SEC_ALLOC | SEC_THREAD_LOCAL | SEC_IS_COMMON
4755 				 | SEC_LINKER_CREATED);
4756 	      tcomm = bfd_make_section_with_flags (abfd, ".tcommon", sflags);
4757 	      if (tcomm == NULL)
4758 		goto error_free_vers;
4759 	    }
4760 	  sec = tcomm;
4761 	}
4762       else if (bed->elf_add_symbol_hook)
4763 	{
4764 	  if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
4765 					     &sec, &value))
4766 	    goto error_free_vers;
4767 
4768 	  /* The hook function sets the name to NULL if this symbol
4769 	     should be skipped for some reason.  */
4770 	  if (name == NULL)
4771 	    continue;
4772 	}
4773 
4774       /* Sanity check that all possibilities were handled.  */
4775       if (sec == NULL)
4776 	abort ();
4777 
4778       /* Silently discard TLS symbols from --just-syms.  There's
4779 	 no way to combine a static TLS block with a new TLS block
4780 	 for this executable.  */
4781       if (ELF_ST_TYPE (isym->st_info) == STT_TLS
4782 	  && sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
4783 	continue;
4784 
4785       if (bfd_is_und_section (sec)
4786 	  || bfd_is_com_section (sec))
4787 	definition = false;
4788       else
4789 	definition = true;
4790 
4791       size_change_ok = false;
4792       type_change_ok = bed->type_change_ok;
4793       old_weak = false;
4794       matched = false;
4795       old_alignment = 0;
4796       old_bfd = NULL;
4797       new_sec = sec;
4798 
4799       if (is_elf_hash_table (&htab->root))
4800 	{
4801 	  Elf_Internal_Versym iver;
4802 	  unsigned int vernum = 0;
4803 	  bool skip;
4804 
4805 	  if (ever == NULL)
4806 	    {
4807 	      if (info->default_imported_symver)
4808 		/* Use the default symbol version created earlier.  */
4809 		iver.vs_vers = elf_tdata (abfd)->cverdefs;
4810 	      else
4811 		iver.vs_vers = 0;
4812 	    }
4813 	  else if (ever >= extversym_end)
4814 	    {
4815 	      /* xgettext:c-format */
4816 	      _bfd_error_handler (_("%pB: not enough version information"),
4817 				  abfd);
4818 	      bfd_set_error (bfd_error_bad_value);
4819 	      goto error_free_vers;
4820 	    }
4821 	  else
4822 	    _bfd_elf_swap_versym_in (abfd, ever, &iver);
4823 
4824 	  vernum = iver.vs_vers & VERSYM_VERSION;
4825 
4826 	  /* If this is a hidden symbol, or if it is not version
4827 	     1, we append the version name to the symbol name.
4828 	     However, we do not modify a non-hidden absolute symbol
4829 	     if it is not a function, because it might be the version
4830 	     symbol itself.  FIXME: What if it isn't?  */
4831 	  if ((iver.vs_vers & VERSYM_HIDDEN) != 0
4832 	      || (vernum > 1
4833 		  && (!bfd_is_abs_section (sec)
4834 		      || bed->is_function_type (ELF_ST_TYPE (isym->st_info)))))
4835 	    {
4836 	      const char *verstr;
4837 	      size_t namelen, verlen, newlen;
4838 	      char *newname, *p;
4839 
4840 	      if (isym->st_shndx != SHN_UNDEF)
4841 		{
4842 		  if (vernum > elf_tdata (abfd)->cverdefs)
4843 		    verstr = NULL;
4844 		  else if (vernum > 1)
4845 		    verstr =
4846 		      elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
4847 		  else
4848 		    verstr = "";
4849 
4850 		  if (verstr == NULL)
4851 		    {
4852 		      _bfd_error_handler
4853 			/* xgettext:c-format */
4854 			(_("%pB: %s: invalid version %u (max %d)"),
4855 			 abfd, name, vernum,
4856 			 elf_tdata (abfd)->cverdefs);
4857 		      bfd_set_error (bfd_error_bad_value);
4858 		      goto error_free_vers;
4859 		    }
4860 		}
4861 	      else
4862 		{
4863 		  /* We cannot simply test for the number of
4864 		     entries in the VERNEED section since the
4865 		     numbers for the needed versions do not start
4866 		     at 0.  */
4867 		  Elf_Internal_Verneed *t;
4868 
4869 		  verstr = NULL;
4870 		  for (t = elf_tdata (abfd)->verref;
4871 		       t != NULL;
4872 		       t = t->vn_nextref)
4873 		    {
4874 		      Elf_Internal_Vernaux *a;
4875 
4876 		      for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
4877 			{
4878 			  if (a->vna_other == vernum)
4879 			    {
4880 			      verstr = a->vna_nodename;
4881 			      break;
4882 			    }
4883 			}
4884 		      if (a != NULL)
4885 			break;
4886 		    }
4887 		  if (verstr == NULL)
4888 		    {
4889 		      _bfd_error_handler
4890 			/* xgettext:c-format */
4891 			(_("%pB: %s: invalid needed version %d"),
4892 			 abfd, name, vernum);
4893 		      bfd_set_error (bfd_error_bad_value);
4894 		      goto error_free_vers;
4895 		    }
4896 		}
4897 
4898 	      namelen = strlen (name);
4899 	      verlen = strlen (verstr);
4900 	      newlen = namelen + verlen + 2;
4901 	      if ((iver.vs_vers & VERSYM_HIDDEN) == 0
4902 		  && isym->st_shndx != SHN_UNDEF)
4903 		++newlen;
4904 
4905 	      newname = (char *) bfd_hash_allocate (&htab->root.table, newlen);
4906 	      if (newname == NULL)
4907 		goto error_free_vers;
4908 	      memcpy (newname, name, namelen);
4909 	      p = newname + namelen;
4910 	      *p++ = ELF_VER_CHR;
4911 	      /* If this is a defined non-hidden version symbol,
4912 		 we add another @ to the name.  This indicates the
4913 		 default version of the symbol.  */
4914 	      if ((iver.vs_vers & VERSYM_HIDDEN) == 0
4915 		  && isym->st_shndx != SHN_UNDEF)
4916 		*p++ = ELF_VER_CHR;
4917 	      memcpy (p, verstr, verlen + 1);
4918 
4919 	      name = newname;
4920 	    }
4921 
4922 	  /* If this symbol has default visibility and the user has
4923 	     requested we not re-export it, then mark it as hidden.  */
4924 	  if (!bfd_is_und_section (sec)
4925 	      && !dynamic
4926 	      && abfd->no_export
4927 	      && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
4928 	    isym->st_other = (STV_HIDDEN
4929 			      | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
4930 
4931 	  if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec, &value,
4932 				      sym_hash, &old_bfd, &old_weak,
4933 				      &old_alignment, &skip, &override,
4934 				      &type_change_ok, &size_change_ok,
4935 				      &matched))
4936 	    goto error_free_vers;
4937 
4938 	  if (skip)
4939 	    continue;
4940 
4941 	  /* Override a definition only if the new symbol matches the
4942 	     existing one.  */
4943 	  if (override && matched)
4944 	    definition = false;
4945 
4946 	  h = *sym_hash;
4947 	  while (h->root.type == bfd_link_hash_indirect
4948 		 || h->root.type == bfd_link_hash_warning)
4949 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
4950 
4951 	  if (elf_tdata (abfd)->verdef != NULL
4952 	      && vernum > 1
4953 	      && definition)
4954 	    h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
4955 	}
4956 
4957       if (! (_bfd_generic_link_add_one_symbol
4958 	     (info, override ? override : abfd, name, flags, sec, value,
4959 	      NULL, false, bed->collect,
4960 	      (struct bfd_link_hash_entry **) sym_hash)))
4961 	goto error_free_vers;
4962 
4963       h = *sym_hash;
4964       /* We need to make sure that indirect symbol dynamic flags are
4965 	 updated.  */
4966       hi = h;
4967       while (h->root.type == bfd_link_hash_indirect
4968 	     || h->root.type == bfd_link_hash_warning)
4969 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
4970 
4971       *sym_hash = h;
4972 
4973       /* Setting the index to -3 tells elf_link_output_extsym that
4974 	 this symbol is defined in a discarded section.  */
4975       if (discarded && is_elf_hash_table (&htab->root))
4976 	h->indx = -3;
4977 
4978       new_weak = (flags & BSF_WEAK) != 0;
4979       if (dynamic
4980 	  && definition
4981 	  && new_weak
4982 	  && !bed->is_function_type (ELF_ST_TYPE (isym->st_info))
4983 	  && is_elf_hash_table (&htab->root)
4984 	  && h->u.alias == NULL)
4985 	{
4986 	  /* Keep a list of all weak defined non function symbols from
4987 	     a dynamic object, using the alias field.  Later in this
4988 	     function we will set the alias field to the correct
4989 	     value.  We only put non-function symbols from dynamic
4990 	     objects on this list, because that happens to be the only
4991 	     time we need to know the normal symbol corresponding to a
4992 	     weak symbol, and the information is time consuming to
4993 	     figure out.  If the alias field is not already NULL,
4994 	     then this symbol was already defined by some previous
4995 	     dynamic object, and we will be using that previous
4996 	     definition anyhow.  */
4997 
4998 	  h->u.alias = weaks;
4999 	  weaks = h;
5000 	}
5001 
5002       /* Set the alignment of a common symbol.  */
5003       if ((common || bfd_is_com_section (sec))
5004 	  && h->root.type == bfd_link_hash_common)
5005 	{
5006 	  unsigned int align;
5007 
5008 	  if (common)
5009 	    align = bfd_log2 (isym->st_value);
5010 	  else
5011 	    {
5012 	      /* The new symbol is a common symbol in a shared object.
5013 		 We need to get the alignment from the section.  */
5014 	      align = new_sec->alignment_power;
5015 	    }
5016 	  if (align > old_alignment)
5017 	    h->root.u.c.p->alignment_power = align;
5018 	  else
5019 	    h->root.u.c.p->alignment_power = old_alignment;
5020 	}
5021 
5022       if (is_elf_hash_table (&htab->root))
5023 	{
5024 	  /* Set a flag in the hash table entry indicating the type of
5025 	     reference or definition we just found.  A dynamic symbol
5026 	     is one which is referenced or defined by both a regular
5027 	     object and a shared object.  */
5028 	  bool dynsym = false;
5029 
5030 	  /* Plugin symbols aren't normal.  Don't set def/ref flags.  */
5031 	  if ((abfd->flags & BFD_PLUGIN) != 0)
5032 	    {
5033 	      /* Except for this flag to track nonweak references.  */
5034 	      if (!definition
5035 		  && bind != STB_WEAK)
5036 		h->ref_ir_nonweak = 1;
5037 	    }
5038 	  else if (!dynamic)
5039 	    {
5040 	      if (! definition)
5041 		{
5042 		  h->ref_regular = 1;
5043 		  if (bind != STB_WEAK)
5044 		    h->ref_regular_nonweak = 1;
5045 		}
5046 	      else
5047 		{
5048 		  h->def_regular = 1;
5049 		  if (h->def_dynamic)
5050 		    {
5051 		      h->def_dynamic = 0;
5052 		      h->ref_dynamic = 1;
5053 		    }
5054 		}
5055 	    }
5056 	  else
5057 	    {
5058 	      if (! definition)
5059 		{
5060 		  h->ref_dynamic = 1;
5061 		  hi->ref_dynamic = 1;
5062 		}
5063 	      else
5064 		{
5065 		  h->def_dynamic = 1;
5066 		  hi->def_dynamic = 1;
5067 		}
5068 	    }
5069 
5070 	  /* If an indirect symbol has been forced local, don't
5071 	     make the real symbol dynamic.  */
5072 	  if (h != hi && hi->forced_local)
5073 	    ;
5074 	  else if (!dynamic)
5075 	    {
5076 	      if (bfd_link_dll (info)
5077 		  || h->def_dynamic
5078 		  || h->ref_dynamic)
5079 		dynsym = true;
5080 	    }
5081 	  else
5082 	    {
5083 	      if (h->def_regular
5084 		  || h->ref_regular
5085 		  || (h->is_weakalias
5086 		      && weakdef (h)->dynindx != -1))
5087 		dynsym = true;
5088 	    }
5089 
5090 	  /* Check to see if we need to add an indirect symbol for
5091 	     the default name.  */
5092 	  if ((definition
5093 	       || (!override && h->root.type == bfd_link_hash_common))
5094 	      && !(hi != h
5095 		   && hi->versioned == versioned_hidden))
5096 	    if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
5097 					      sec, value, &old_bfd, &dynsym))
5098 	      goto error_free_vers;
5099 
5100 	  /* Check the alignment when a common symbol is involved. This
5101 	     can change when a common symbol is overridden by a normal
5102 	     definition or a common symbol is ignored due to the old
5103 	     normal definition. We need to make sure the maximum
5104 	     alignment is maintained.  */
5105 	  if ((old_alignment || common)
5106 	      && h->root.type != bfd_link_hash_common)
5107 	    {
5108 	      unsigned int common_align;
5109 	      unsigned int normal_align;
5110 	      unsigned int symbol_align;
5111 	      bfd *normal_bfd;
5112 	      bfd *common_bfd;
5113 
5114 	      BFD_ASSERT (h->root.type == bfd_link_hash_defined
5115 			  || h->root.type == bfd_link_hash_defweak);
5116 
5117 	      symbol_align = ffs (h->root.u.def.value) - 1;
5118 	      if (h->root.u.def.section->owner != NULL
5119 		  && (h->root.u.def.section->owner->flags
5120 		       & (DYNAMIC | BFD_PLUGIN)) == 0)
5121 		{
5122 		  normal_align = h->root.u.def.section->alignment_power;
5123 		  if (normal_align > symbol_align)
5124 		    normal_align = symbol_align;
5125 		}
5126 	      else
5127 		normal_align = symbol_align;
5128 
5129 	      if (old_alignment)
5130 		{
5131 		  common_align = old_alignment;
5132 		  common_bfd = old_bfd;
5133 		  normal_bfd = abfd;
5134 		}
5135 	      else
5136 		{
5137 		  common_align = bfd_log2 (isym->st_value);
5138 		  common_bfd = abfd;
5139 		  normal_bfd = old_bfd;
5140 		}
5141 
5142 	      if (normal_align < common_align)
5143 		{
5144 		  /* PR binutils/2735 */
5145 		  if (normal_bfd == NULL)
5146 		    _bfd_error_handler
5147 		      /* xgettext:c-format */
5148 		      (_("warning: alignment %u of common symbol `%s' in %pB is"
5149 			 " greater than the alignment (%u) of its section %pA"),
5150 		       1 << common_align, name, common_bfd,
5151 		       1 << normal_align, h->root.u.def.section);
5152 		  else
5153 		    _bfd_error_handler
5154 		      /* xgettext:c-format */
5155 		      (_("warning: alignment %u of symbol `%s' in %pB"
5156 			 " is smaller than %u in %pB"),
5157 		       1 << normal_align, name, normal_bfd,
5158 		       1 << common_align, common_bfd);
5159 		}
5160 	    }
5161 
5162 	  /* Remember the symbol size if it isn't undefined.  */
5163 	  if (isym->st_size != 0
5164 	      && isym->st_shndx != SHN_UNDEF
5165 	      && (definition || h->size == 0))
5166 	    {
5167 	      if (h->size != 0
5168 		  && h->size != isym->st_size
5169 		  && ! size_change_ok)
5170 		_bfd_error_handler
5171 		  /* xgettext:c-format */
5172 		  (_("warning: size of symbol `%s' changed"
5173 		     " from %" PRIu64 " in %pB to %" PRIu64 " in %pB"),
5174 		   name, (uint64_t) h->size, old_bfd,
5175 		   (uint64_t) isym->st_size, abfd);
5176 
5177 	      h->size = isym->st_size;
5178 	    }
5179 
5180 	  /* If this is a common symbol, then we always want H->SIZE
5181 	     to be the size of the common symbol.  The code just above
5182 	     won't fix the size if a common symbol becomes larger.  We
5183 	     don't warn about a size change here, because that is
5184 	     covered by --warn-common.  Allow changes between different
5185 	     function types.  */
5186 	  if (h->root.type == bfd_link_hash_common)
5187 	    h->size = h->root.u.c.size;
5188 
5189 	  if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
5190 	      && ((definition && !new_weak)
5191 		  || (old_weak && h->root.type == bfd_link_hash_common)
5192 		  || h->type == STT_NOTYPE))
5193 	    {
5194 	      unsigned int type = ELF_ST_TYPE (isym->st_info);
5195 
5196 	      /* Turn an IFUNC symbol from a DSO into a normal FUNC
5197 		 symbol.  */
5198 	      if (type == STT_GNU_IFUNC
5199 		  && (abfd->flags & DYNAMIC) != 0)
5200 		type = STT_FUNC;
5201 
5202 	      if (h->type != type)
5203 		{
5204 		  if (h->type != STT_NOTYPE && ! type_change_ok)
5205 		    /* xgettext:c-format */
5206 		    _bfd_error_handler
5207 		      (_("warning: type of symbol `%s' changed"
5208 			 " from %d to %d in %pB"),
5209 		       name, h->type, type, abfd);
5210 
5211 		  h->type = type;
5212 		}
5213 	    }
5214 
5215 	  /* Merge st_other field.  */
5216 	  elf_merge_st_other (abfd, h, isym->st_other, sec,
5217 			      definition, dynamic);
5218 
5219 	  /* We don't want to make debug symbol dynamic.  */
5220 	  if (definition
5221 	      && (sec->flags & SEC_DEBUGGING)
5222 	      && !bfd_link_relocatable (info))
5223 	    dynsym = false;
5224 
5225 	  /* Nor should we make plugin symbols dynamic.  */
5226 	  if ((abfd->flags & BFD_PLUGIN) != 0)
5227 	    dynsym = false;
5228 
5229 	  if (definition)
5230 	    {
5231 	      h->target_internal = isym->st_target_internal;
5232 	      h->unique_global = (flags & BSF_GNU_UNIQUE) != 0;
5233 	    }
5234 
5235 	  if (definition && !dynamic)
5236 	    {
5237 	      char *p = strchr (name, ELF_VER_CHR);
5238 	      if (p != NULL && p[1] != ELF_VER_CHR)
5239 		{
5240 		  /* Queue non-default versions so that .symver x, x@FOO
5241 		     aliases can be checked.  */
5242 		  if (!nondeflt_vers)
5243 		    {
5244 		      size_t amt = ((isymend - isym + 1)
5245 				    * sizeof (struct elf_link_hash_entry *));
5246 		      nondeflt_vers
5247 			= (struct elf_link_hash_entry **) bfd_malloc (amt);
5248 		      if (!nondeflt_vers)
5249 			goto error_free_vers;
5250 		    }
5251 		  nondeflt_vers[nondeflt_vers_cnt++] = h;
5252 		}
5253 	    }
5254 
5255 	  if (dynsym && h->dynindx == -1)
5256 	    {
5257 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
5258 		goto error_free_vers;
5259 	      if (h->is_weakalias
5260 		  && weakdef (h)->dynindx == -1)
5261 		{
5262 		  if (!bfd_elf_link_record_dynamic_symbol (info, weakdef (h)))
5263 		    goto error_free_vers;
5264 		}
5265 	    }
5266 	  else if (h->dynindx != -1)
5267 	    /* If the symbol already has a dynamic index, but
5268 	       visibility says it should not be visible, turn it into
5269 	       a local symbol.  */
5270 	    switch (ELF_ST_VISIBILITY (h->other))
5271 	      {
5272 	      case STV_INTERNAL:
5273 	      case STV_HIDDEN:
5274 		(*bed->elf_backend_hide_symbol) (info, h, true);
5275 		dynsym = false;
5276 		break;
5277 	      }
5278 
5279 	  if (!add_needed
5280 	      && matched
5281 	      && definition
5282 	      && h->root.type != bfd_link_hash_indirect
5283 	      && ((dynsym
5284 		   && h->ref_regular_nonweak)
5285 		  || (old_bfd != NULL
5286 		      && (old_bfd->flags & BFD_PLUGIN) != 0
5287 		      && h->ref_ir_nonweak
5288 		      && !info->lto_all_symbols_read)
5289 		  || (h->ref_dynamic_nonweak
5290 		      && (elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0
5291 		      && !on_needed_list (elf_dt_name (abfd),
5292 					  htab->needed, NULL))))
5293 	    {
5294 	      const char *soname = elf_dt_name (abfd);
5295 
5296 	      info->callbacks->minfo ("%!", soname, old_bfd,
5297 				      h->root.root.string);
5298 
5299 	      /* A symbol from a library loaded via DT_NEEDED of some
5300 		 other library is referenced by a regular object.
5301 		 Add a DT_NEEDED entry for it.  Issue an error if
5302 		 --no-add-needed is used and the reference was not
5303 		 a weak one.  */
5304 	      if (old_bfd != NULL
5305 		  && (elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
5306 		{
5307 		  _bfd_error_handler
5308 		    /* xgettext:c-format */
5309 		    (_("%pB: undefined reference to symbol '%s'"),
5310 		     old_bfd, name);
5311 		  bfd_set_error (bfd_error_missing_dso);
5312 		  goto error_free_vers;
5313 		}
5314 
5315 	      elf_dyn_lib_class (abfd) = (enum dynamic_lib_link_class)
5316 		(elf_dyn_lib_class (abfd) & ~DYN_AS_NEEDED);
5317 
5318 	      /* Create dynamic sections for backends that require
5319 		 that be done before setup_gnu_properties.  */
5320 	      if (!_bfd_elf_link_create_dynamic_sections (abfd, info))
5321 		return false;
5322 	      add_needed = true;
5323 	    }
5324 	}
5325     }
5326 
5327   if (info->lto_plugin_active
5328       && !bfd_link_relocatable (info)
5329       && (abfd->flags & BFD_PLUGIN) == 0
5330       && !just_syms
5331       && extsymcount)
5332     {
5333       int r_sym_shift;
5334 
5335       if (bed->s->arch_size == 32)
5336 	r_sym_shift = 8;
5337       else
5338 	r_sym_shift = 32;
5339 
5340       /* If linker plugin is enabled, set non_ir_ref_regular on symbols
5341 	 referenced in regular objects so that linker plugin will get
5342 	 the correct symbol resolution.  */
5343 
5344       sym_hash = elf_sym_hashes (abfd);
5345       for (s = abfd->sections; s != NULL; s = s->next)
5346 	{
5347 	  Elf_Internal_Rela *internal_relocs;
5348 	  Elf_Internal_Rela *rel, *relend;
5349 
5350 	  /* Don't check relocations in excluded sections.  */
5351 	  if ((s->flags & SEC_RELOC) == 0
5352 	      || s->reloc_count == 0
5353 	      || (s->flags & SEC_EXCLUDE) != 0
5354 	      || ((info->strip == strip_all
5355 		   || info->strip == strip_debugger)
5356 		  && (s->flags & SEC_DEBUGGING) != 0))
5357 	    continue;
5358 
5359 	  internal_relocs = _bfd_elf_link_read_relocs (abfd, s, NULL,
5360 						       NULL,
5361 						       info->keep_memory);
5362 	  if (internal_relocs == NULL)
5363 	    goto error_free_vers;
5364 
5365 	  rel = internal_relocs;
5366 	  relend = rel + s->reloc_count;
5367 	  for ( ; rel < relend; rel++)
5368 	    {
5369 	      unsigned long r_symndx = rel->r_info >> r_sym_shift;
5370 	      struct elf_link_hash_entry *h;
5371 
5372 	      /* Skip local symbols.  */
5373 	      if (r_symndx < extsymoff)
5374 		continue;
5375 
5376 	      h = sym_hash[r_symndx - extsymoff];
5377 	      if (h != NULL)
5378 		h->root.non_ir_ref_regular = 1;
5379 	    }
5380 
5381 	  if (elf_section_data (s)->relocs != internal_relocs)
5382 	    free (internal_relocs);
5383 	}
5384     }
5385 
5386   free (extversym);
5387   extversym = NULL;
5388   free (isymbuf);
5389   isymbuf = NULL;
5390 
5391   if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
5392     {
5393       unsigned int i;
5394 
5395       /* Restore the symbol table.  */
5396       old_ent = (char *) old_tab + tabsize;
5397       memset (elf_sym_hashes (abfd), 0,
5398 	      extsymcount * sizeof (struct elf_link_hash_entry *));
5399       htab->root.table.table = old_table;
5400       htab->root.table.size = old_size;
5401       htab->root.table.count = old_count;
5402       memcpy (htab->root.table.table, old_tab, tabsize);
5403       htab->root.undefs = old_undefs;
5404       htab->root.undefs_tail = old_undefs_tail;
5405       if (htab->dynstr != NULL)
5406 	_bfd_elf_strtab_restore (htab->dynstr, old_strtab);
5407       free (old_strtab);
5408       old_strtab = NULL;
5409       for (i = 0; i < htab->root.table.size; i++)
5410 	{
5411 	  struct bfd_hash_entry *p;
5412 	  struct elf_link_hash_entry *h;
5413 	  unsigned int non_ir_ref_dynamic;
5414 
5415 	  for (p = htab->root.table.table[i]; p != NULL; p = p->next)
5416 	    {
5417 	      /* Preserve non_ir_ref_dynamic so that this symbol
5418 		 will be exported when the dynamic lib becomes needed
5419 		 in the second pass.  */
5420 	      h = (struct elf_link_hash_entry *) p;
5421 	      if (h->root.type == bfd_link_hash_warning)
5422 		h = (struct elf_link_hash_entry *) h->root.u.i.link;
5423 	      non_ir_ref_dynamic = h->root.non_ir_ref_dynamic;
5424 
5425 	      h = (struct elf_link_hash_entry *) p;
5426 	      memcpy (h, old_ent, htab->root.table.entsize);
5427 	      old_ent = (char *) old_ent + htab->root.table.entsize;
5428 	      if (h->root.type == bfd_link_hash_warning)
5429 		{
5430 		  h = (struct elf_link_hash_entry *) h->root.u.i.link;
5431 		  memcpy (h, old_ent, htab->root.table.entsize);
5432 		  old_ent = (char *) old_ent + htab->root.table.entsize;
5433 		}
5434 	      if (h->root.type == bfd_link_hash_common)
5435 		{
5436 		  memcpy (h->root.u.c.p, old_ent, sizeof (*h->root.u.c.p));
5437 		  old_ent = (char *) old_ent + sizeof (*h->root.u.c.p);
5438 		}
5439 	      h->root.non_ir_ref_dynamic = non_ir_ref_dynamic;
5440 	    }
5441 	}
5442 
5443       /* Make a special call to the linker "notice" function to
5444 	 tell it that symbols added for crefs may need to be removed.  */
5445       if (!(*bed->notice_as_needed) (abfd, info, notice_not_needed))
5446 	goto error_free_vers;
5447 
5448       free (old_tab);
5449       objalloc_free_block ((struct objalloc *) htab->root.table.memory,
5450 			   alloc_mark);
5451       free (nondeflt_vers);
5452       return true;
5453     }
5454 
5455   if (old_tab != NULL)
5456     {
5457       if (!(*bed->notice_as_needed) (abfd, info, notice_needed))
5458 	goto error_free_vers;
5459       free (old_tab);
5460       old_tab = NULL;
5461     }
5462 
5463   /* Now that all the symbols from this input file are created, if
5464      not performing a relocatable link, handle .symver foo, foo@BAR
5465      such that any relocs against foo become foo@BAR.  */
5466   if (!bfd_link_relocatable (info) && nondeflt_vers != NULL)
5467     {
5468       size_t cnt, symidx;
5469 
5470       for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
5471 	{
5472 	  struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
5473 	  char *shortname, *p;
5474 	  size_t amt;
5475 
5476 	  p = strchr (h->root.root.string, ELF_VER_CHR);
5477 	  if (p == NULL
5478 	      || (h->root.type != bfd_link_hash_defined
5479 		  && h->root.type != bfd_link_hash_defweak))
5480 	    continue;
5481 
5482 	  amt = p - h->root.root.string;
5483 	  shortname = (char *) bfd_malloc (amt + 1);
5484 	  if (!shortname)
5485 	    goto error_free_vers;
5486 	  memcpy (shortname, h->root.root.string, amt);
5487 	  shortname[amt] = '\0';
5488 
5489 	  hi = (struct elf_link_hash_entry *)
5490 	       bfd_link_hash_lookup (&htab->root, shortname,
5491 				     false, false, false);
5492 	  if (hi != NULL
5493 	      && hi->root.type == h->root.type
5494 	      && hi->root.u.def.value == h->root.u.def.value
5495 	      && hi->root.u.def.section == h->root.u.def.section)
5496 	    {
5497 	      (*bed->elf_backend_hide_symbol) (info, hi, true);
5498 	      hi->root.type = bfd_link_hash_indirect;
5499 	      hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
5500 	      (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
5501 	      sym_hash = elf_sym_hashes (abfd);
5502 	      if (sym_hash)
5503 		for (symidx = 0; symidx < extsymcount; ++symidx)
5504 		  if (sym_hash[symidx] == hi)
5505 		    {
5506 		      sym_hash[symidx] = h;
5507 		      break;
5508 		    }
5509 	    }
5510 	  free (shortname);
5511 	}
5512       free (nondeflt_vers);
5513       nondeflt_vers = NULL;
5514     }
5515 
5516   /* Now set the alias field correctly for all the weak defined
5517      symbols we found.  The only way to do this is to search all the
5518      symbols.  Since we only need the information for non functions in
5519      dynamic objects, that's the only time we actually put anything on
5520      the list WEAKS.  We need this information so that if a regular
5521      object refers to a symbol defined weakly in a dynamic object, the
5522      real symbol in the dynamic object is also put in the dynamic
5523      symbols; we also must arrange for both symbols to point to the
5524      same memory location.  We could handle the general case of symbol
5525      aliasing, but a general symbol alias can only be generated in
5526      assembler code, handling it correctly would be very time
5527      consuming, and other ELF linkers don't handle general aliasing
5528      either.  */
5529   if (weaks != NULL)
5530     {
5531       struct elf_link_hash_entry **hpp;
5532       struct elf_link_hash_entry **hppend;
5533       struct elf_link_hash_entry **sorted_sym_hash;
5534       struct elf_link_hash_entry *h;
5535       size_t sym_count, amt;
5536 
5537       /* Since we have to search the whole symbol list for each weak
5538 	 defined symbol, search time for N weak defined symbols will be
5539 	 O(N^2). Binary search will cut it down to O(NlogN).  */
5540       amt = extsymcount * sizeof (*sorted_sym_hash);
5541       sorted_sym_hash = bfd_malloc (amt);
5542       if (sorted_sym_hash == NULL)
5543 	goto error_return;
5544       sym_hash = sorted_sym_hash;
5545       hpp = elf_sym_hashes (abfd);
5546       hppend = hpp + extsymcount;
5547       sym_count = 0;
5548       for (; hpp < hppend; hpp++)
5549 	{
5550 	  h = *hpp;
5551 	  if (h != NULL
5552 	      && h->root.type == bfd_link_hash_defined
5553 	      && !bed->is_function_type (h->type))
5554 	    {
5555 	      *sym_hash = h;
5556 	      sym_hash++;
5557 	      sym_count++;
5558 	    }
5559 	}
5560 
5561       qsort (sorted_sym_hash, sym_count, sizeof (*sorted_sym_hash),
5562 	     elf_sort_symbol);
5563 
5564       while (weaks != NULL)
5565 	{
5566 	  struct elf_link_hash_entry *hlook;
5567 	  asection *slook;
5568 	  bfd_vma vlook;
5569 	  size_t i, j, idx = 0;
5570 
5571 	  hlook = weaks;
5572 	  weaks = hlook->u.alias;
5573 	  hlook->u.alias = NULL;
5574 
5575 	  if (hlook->root.type != bfd_link_hash_defined
5576 	      && hlook->root.type != bfd_link_hash_defweak)
5577 	    continue;
5578 
5579 	  slook = hlook->root.u.def.section;
5580 	  vlook = hlook->root.u.def.value;
5581 
5582 	  i = 0;
5583 	  j = sym_count;
5584 	  while (i != j)
5585 	    {
5586 	      bfd_signed_vma vdiff;
5587 	      idx = (i + j) / 2;
5588 	      h = sorted_sym_hash[idx];
5589 	      vdiff = vlook - h->root.u.def.value;
5590 	      if (vdiff < 0)
5591 		j = idx;
5592 	      else if (vdiff > 0)
5593 		i = idx + 1;
5594 	      else
5595 		{
5596 		  int sdiff = slook->id - h->root.u.def.section->id;
5597 		  if (sdiff < 0)
5598 		    j = idx;
5599 		  else if (sdiff > 0)
5600 		    i = idx + 1;
5601 		  else
5602 		    break;
5603 		}
5604 	    }
5605 
5606 	  /* We didn't find a value/section match.  */
5607 	  if (i == j)
5608 	    continue;
5609 
5610 	  /* With multiple aliases, or when the weak symbol is already
5611 	     strongly defined, we have multiple matching symbols and
5612 	     the binary search above may land on any of them.  Step
5613 	     one past the matching symbol(s).  */
5614 	  while (++idx != j)
5615 	    {
5616 	      h = sorted_sym_hash[idx];
5617 	      if (h->root.u.def.section != slook
5618 		  || h->root.u.def.value != vlook)
5619 		break;
5620 	    }
5621 
5622 	  /* Now look back over the aliases.  Since we sorted by size
5623 	     as well as value and section, we'll choose the one with
5624 	     the largest size.  */
5625 	  while (idx-- != i)
5626 	    {
5627 	      h = sorted_sym_hash[idx];
5628 
5629 	      /* Stop if value or section doesn't match.  */
5630 	      if (h->root.u.def.section != slook
5631 		  || h->root.u.def.value != vlook)
5632 		break;
5633 	      else if (h != hlook)
5634 		{
5635 		  struct elf_link_hash_entry *t;
5636 
5637 		  hlook->u.alias = h;
5638 		  hlook->is_weakalias = 1;
5639 		  t = h;
5640 		  if (t->u.alias != NULL)
5641 		    while (t->u.alias != h)
5642 		      t = t->u.alias;
5643 		  t->u.alias = hlook;
5644 
5645 		  /* If the weak definition is in the list of dynamic
5646 		     symbols, make sure the real definition is put
5647 		     there as well.  */
5648 		  if (hlook->dynindx != -1 && h->dynindx == -1)
5649 		    {
5650 		      if (! bfd_elf_link_record_dynamic_symbol (info, h))
5651 			{
5652 			err_free_sym_hash:
5653 			  free (sorted_sym_hash);
5654 			  goto error_return;
5655 			}
5656 		    }
5657 
5658 		  /* If the real definition is in the list of dynamic
5659 		     symbols, make sure the weak definition is put
5660 		     there as well.  If we don't do this, then the
5661 		     dynamic loader might not merge the entries for the
5662 		     real definition and the weak definition.  */
5663 		  if (h->dynindx != -1 && hlook->dynindx == -1)
5664 		    {
5665 		      if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
5666 			goto err_free_sym_hash;
5667 		    }
5668 		  break;
5669 		}
5670 	    }
5671 	}
5672 
5673       free (sorted_sym_hash);
5674     }
5675 
5676   if (bed->check_directives
5677       && !(*bed->check_directives) (abfd, info))
5678     return false;
5679 
5680   /* If this is a non-traditional link, try to optimize the handling
5681      of the .stab/.stabstr sections.  */
5682   if (! dynamic
5683       && ! info->traditional_format
5684       && is_elf_hash_table (&htab->root)
5685       && (info->strip != strip_all && info->strip != strip_debugger))
5686     {
5687       asection *stabstr;
5688 
5689       stabstr = bfd_get_section_by_name (abfd, ".stabstr");
5690       if (stabstr != NULL)
5691 	{
5692 	  bfd_size_type string_offset = 0;
5693 	  asection *stab;
5694 
5695 	  for (stab = abfd->sections; stab; stab = stab->next)
5696 	    if (startswith (stab->name, ".stab")
5697 		&& (!stab->name[5] ||
5698 		    (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
5699 		&& (stab->flags & SEC_MERGE) == 0
5700 		&& !bfd_is_abs_section (stab->output_section))
5701 	      {
5702 		struct bfd_elf_section_data *secdata;
5703 
5704 		secdata = elf_section_data (stab);
5705 		if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
5706 					       stabstr, &secdata->sec_info,
5707 					       &string_offset))
5708 		  goto error_return;
5709 		if (secdata->sec_info)
5710 		  stab->sec_info_type = SEC_INFO_TYPE_STABS;
5711 	    }
5712 	}
5713     }
5714 
5715   if (dynamic && add_needed)
5716     {
5717       /* Add this bfd to the loaded list.  */
5718       struct elf_link_loaded_list *n;
5719 
5720       n = (struct elf_link_loaded_list *) bfd_alloc (abfd, sizeof (*n));
5721       if (n == NULL)
5722 	goto error_return;
5723       n->abfd = abfd;
5724       n->next = htab->dyn_loaded;
5725       htab->dyn_loaded = n;
5726     }
5727   if (dynamic && !add_needed
5728       && (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) != 0)
5729     elf_dyn_lib_class (abfd) |= DYN_NO_NEEDED;
5730 
5731   return true;
5732 
5733  error_free_vers:
5734   free (old_tab);
5735   free (old_strtab);
5736   free (nondeflt_vers);
5737   free (extversym);
5738  error_free_sym:
5739   free (isymbuf);
5740  error_return:
5741   return false;
5742 }
5743 
5744 /* Return the linker hash table entry of a symbol that might be
5745    satisfied by an archive symbol.  Return -1 on error.  */
5746 
5747 struct bfd_link_hash_entry *
_bfd_elf_archive_symbol_lookup(bfd * abfd,struct bfd_link_info * info,const char * name)5748 _bfd_elf_archive_symbol_lookup (bfd *abfd,
5749 				struct bfd_link_info *info,
5750 				const char *name)
5751 {
5752   struct bfd_link_hash_entry *h;
5753   char *p, *copy;
5754   size_t len, first;
5755 
5756   h = bfd_link_hash_lookup (info->hash, name, false, false, true);
5757   if (h != NULL)
5758     return h;
5759 
5760   /* If this is a default version (the name contains @@), look up the
5761      symbol again with only one `@' as well as without the version.
5762      The effect is that references to the symbol with and without the
5763      version will be matched by the default symbol in the archive.  */
5764 
5765   p = strchr (name, ELF_VER_CHR);
5766   if (p == NULL || p[1] != ELF_VER_CHR)
5767     return h;
5768 
5769   /* First check with only one `@'.  */
5770   len = strlen (name);
5771   copy = (char *) bfd_alloc (abfd, len);
5772   if (copy == NULL)
5773     return (struct bfd_link_hash_entry *) -1;
5774 
5775   first = p - name + 1;
5776   memcpy (copy, name, first);
5777   memcpy (copy + first, name + first + 1, len - first);
5778 
5779   h = bfd_link_hash_lookup (info->hash, copy, false, false, true);
5780   if (h == NULL)
5781     {
5782       /* We also need to check references to the symbol without the
5783 	 version.  */
5784       copy[first - 1] = '\0';
5785       h = bfd_link_hash_lookup (info->hash, copy, false, false, true);
5786     }
5787 
5788   bfd_release (abfd, copy);
5789   return h;
5790 }
5791 
5792 /* Add symbols from an ELF archive file to the linker hash table.  We
5793    don't use _bfd_generic_link_add_archive_symbols because we need to
5794    handle versioned symbols.
5795 
5796    Fortunately, ELF archive handling is simpler than that done by
5797    _bfd_generic_link_add_archive_symbols, which has to allow for a.out
5798    oddities.  In ELF, if we find a symbol in the archive map, and the
5799    symbol is currently undefined, we know that we must pull in that
5800    object file.
5801 
5802    Unfortunately, we do have to make multiple passes over the symbol
5803    table until nothing further is resolved.  */
5804 
5805 static bool
elf_link_add_archive_symbols(bfd * abfd,struct bfd_link_info * info)5806 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
5807 {
5808   symindex c;
5809   unsigned char *included = NULL;
5810   carsym *symdefs;
5811   bool loop;
5812   size_t amt;
5813   const struct elf_backend_data *bed;
5814   struct bfd_link_hash_entry * (*archive_symbol_lookup)
5815     (bfd *, struct bfd_link_info *, const char *);
5816 
5817   if (! bfd_has_map (abfd))
5818     {
5819       /* An empty archive is a special case.  */
5820       if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
5821 	return true;
5822       bfd_set_error (bfd_error_no_armap);
5823       return false;
5824     }
5825 
5826   /* Keep track of all symbols we know to be already defined, and all
5827      files we know to be already included.  This is to speed up the
5828      second and subsequent passes.  */
5829   c = bfd_ardata (abfd)->symdef_count;
5830   if (c == 0)
5831     return true;
5832   amt = c * sizeof (*included);
5833   included = (unsigned char *) bfd_zmalloc (amt);
5834   if (included == NULL)
5835     return false;
5836 
5837   symdefs = bfd_ardata (abfd)->symdefs;
5838   bed = get_elf_backend_data (abfd);
5839   archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
5840 
5841   do
5842     {
5843       file_ptr last;
5844       symindex i;
5845       carsym *symdef;
5846       carsym *symdefend;
5847 
5848       loop = false;
5849       last = -1;
5850 
5851       symdef = symdefs;
5852       symdefend = symdef + c;
5853       for (i = 0; symdef < symdefend; symdef++, i++)
5854 	{
5855 	  struct bfd_link_hash_entry *h;
5856 	  bfd *element;
5857 	  struct bfd_link_hash_entry *undefs_tail;
5858 	  symindex mark;
5859 
5860 	  if (included[i])
5861 	    continue;
5862 	  if (symdef->file_offset == last)
5863 	    {
5864 	      included[i] = true;
5865 	      continue;
5866 	    }
5867 
5868 	  h = archive_symbol_lookup (abfd, info, symdef->name);
5869 	  if (h == (struct bfd_link_hash_entry *) -1)
5870 	    goto error_return;
5871 
5872 	  if (h == NULL)
5873 	    continue;
5874 
5875 	  if (h->type == bfd_link_hash_undefined)
5876 	    {
5877 	      /* If the archive element has already been loaded then one
5878 		 of the symbols defined by that element might have been
5879 		 made undefined due to being in a discarded section.  */
5880 	      if (is_elf_hash_table (info->hash)
5881 		  && ((struct elf_link_hash_entry *) h)->indx == -3)
5882 		continue;
5883 	    }
5884 	  else if (h->type == bfd_link_hash_common)
5885 	    {
5886 	      /* We currently have a common symbol.  The archive map contains
5887 		 a reference to this symbol, so we may want to include it.  We
5888 		 only want to include it however, if this archive element
5889 		 contains a definition of the symbol, not just another common
5890 		 declaration of it.
5891 
5892 		 Unfortunately some archivers (including GNU ar) will put
5893 		 declarations of common symbols into their archive maps, as
5894 		 well as real definitions, so we cannot just go by the archive
5895 		 map alone.  Instead we must read in the element's symbol
5896 		 table and check that to see what kind of symbol definition
5897 		 this is.  */
5898 	      if (! elf_link_is_defined_archive_symbol (abfd, symdef))
5899 		continue;
5900 	    }
5901 	  else
5902 	    {
5903 	      if (h->type != bfd_link_hash_undefweak)
5904 		/* Symbol must be defined.  Don't check it again.  */
5905 		included[i] = true;
5906 	      continue;
5907 	    }
5908 
5909 	  /* We need to include this archive member.  */
5910 	  element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
5911 	  if (element == NULL)
5912 	    goto error_return;
5913 
5914 	  if (! bfd_check_format (element, bfd_object))
5915 	    goto error_return;
5916 
5917 	  undefs_tail = info->hash->undefs_tail;
5918 
5919 	  if (!(*info->callbacks
5920 		->add_archive_element) (info, element, symdef->name, &element))
5921 	    continue;
5922 	  if (!bfd_link_add_symbols (element, info))
5923 	    goto error_return;
5924 
5925 	  /* If there are any new undefined symbols, we need to make
5926 	     another pass through the archive in order to see whether
5927 	     they can be defined.  FIXME: This isn't perfect, because
5928 	     common symbols wind up on undefs_tail and because an
5929 	     undefined symbol which is defined later on in this pass
5930 	     does not require another pass.  This isn't a bug, but it
5931 	     does make the code less efficient than it could be.  */
5932 	  if (undefs_tail != info->hash->undefs_tail)
5933 	    loop = true;
5934 
5935 	  /* Look backward to mark all symbols from this object file
5936 	     which we have already seen in this pass.  */
5937 	  mark = i;
5938 	  do
5939 	    {
5940 	      included[mark] = true;
5941 	      if (mark == 0)
5942 		break;
5943 	      --mark;
5944 	    }
5945 	  while (symdefs[mark].file_offset == symdef->file_offset);
5946 
5947 	  /* We mark subsequent symbols from this object file as we go
5948 	     on through the loop.  */
5949 	  last = symdef->file_offset;
5950 	}
5951     }
5952   while (loop);
5953 
5954   free (included);
5955   return true;
5956 
5957  error_return:
5958   free (included);
5959   return false;
5960 }
5961 
5962 /* Given an ELF BFD, add symbols to the global hash table as
5963    appropriate.  */
5964 
5965 bool
bfd_elf_link_add_symbols(bfd * abfd,struct bfd_link_info * info)5966 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
5967 {
5968   switch (bfd_get_format (abfd))
5969     {
5970     case bfd_object:
5971       return elf_link_add_object_symbols (abfd, info);
5972     case bfd_archive:
5973       return elf_link_add_archive_symbols (abfd, info);
5974     default:
5975       bfd_set_error (bfd_error_wrong_format);
5976       return false;
5977     }
5978 }
5979 
5980 struct hash_codes_info
5981 {
5982   unsigned long *hashcodes;
5983   bool error;
5984 };
5985 
5986 /* This function will be called though elf_link_hash_traverse to store
5987    all hash value of the exported symbols in an array.  */
5988 
5989 static bool
elf_collect_hash_codes(struct elf_link_hash_entry * h,void * data)5990 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
5991 {
5992   struct hash_codes_info *inf = (struct hash_codes_info *) data;
5993   const char *name;
5994   unsigned long ha;
5995   char *alc = NULL;
5996 
5997   /* Ignore indirect symbols.  These are added by the versioning code.  */
5998   if (h->dynindx == -1)
5999     return true;
6000 
6001   name = h->root.root.string;
6002   if (h->versioned >= versioned)
6003     {
6004       char *p = strchr (name, ELF_VER_CHR);
6005       if (p != NULL)
6006 	{
6007 	  alc = (char *) bfd_malloc (p - name + 1);
6008 	  if (alc == NULL)
6009 	    {
6010 	      inf->error = true;
6011 	      return false;
6012 	    }
6013 	  memcpy (alc, name, p - name);
6014 	  alc[p - name] = '\0';
6015 	  name = alc;
6016 	}
6017     }
6018 
6019   /* Compute the hash value.  */
6020   ha = bfd_elf_hash (name);
6021 
6022   /* Store the found hash value in the array given as the argument.  */
6023   *(inf->hashcodes)++ = ha;
6024 
6025   /* And store it in the struct so that we can put it in the hash table
6026      later.  */
6027   h->u.elf_hash_value = ha;
6028 
6029   free (alc);
6030   return true;
6031 }
6032 
6033 struct collect_gnu_hash_codes
6034 {
6035   bfd *output_bfd;
6036   const struct elf_backend_data *bed;
6037   unsigned long int nsyms;
6038   unsigned long int maskbits;
6039   unsigned long int *hashcodes;
6040   unsigned long int *hashval;
6041   unsigned long int *indx;
6042   unsigned long int *counts;
6043   bfd_vma *bitmask;
6044   bfd_byte *contents;
6045   bfd_size_type xlat;
6046   long int min_dynindx;
6047   unsigned long int bucketcount;
6048   unsigned long int symindx;
6049   long int local_indx;
6050   long int shift1, shift2;
6051   unsigned long int mask;
6052   bool error;
6053 };
6054 
6055 /* This function will be called though elf_link_hash_traverse to store
6056    all hash value of the exported symbols in an array.  */
6057 
6058 static bool
elf_collect_gnu_hash_codes(struct elf_link_hash_entry * h,void * data)6059 elf_collect_gnu_hash_codes (struct elf_link_hash_entry *h, void *data)
6060 {
6061   struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
6062   const char *name;
6063   unsigned long ha;
6064   char *alc = NULL;
6065 
6066   /* Ignore indirect symbols.  These are added by the versioning code.  */
6067   if (h->dynindx == -1)
6068     return true;
6069 
6070   /* Ignore also local symbols and undefined symbols.  */
6071   if (! (*s->bed->elf_hash_symbol) (h))
6072     return true;
6073 
6074   name = h->root.root.string;
6075   if (h->versioned >= versioned)
6076     {
6077       char *p = strchr (name, ELF_VER_CHR);
6078       if (p != NULL)
6079 	{
6080 	  alc = (char *) bfd_malloc (p - name + 1);
6081 	  if (alc == NULL)
6082 	    {
6083 	      s->error = true;
6084 	      return false;
6085 	    }
6086 	  memcpy (alc, name, p - name);
6087 	  alc[p - name] = '\0';
6088 	  name = alc;
6089 	}
6090     }
6091 
6092   /* Compute the hash value.  */
6093   ha = bfd_elf_gnu_hash (name);
6094 
6095   /* Store the found hash value in the array for compute_bucket_count,
6096      and also for .dynsym reordering purposes.  */
6097   s->hashcodes[s->nsyms] = ha;
6098   s->hashval[h->dynindx] = ha;
6099   ++s->nsyms;
6100   if (s->min_dynindx < 0 || s->min_dynindx > h->dynindx)
6101     s->min_dynindx = h->dynindx;
6102 
6103   free (alc);
6104   return true;
6105 }
6106 
6107 /* This function will be called though elf_link_hash_traverse to do
6108    final dynamic symbol renumbering in case of .gnu.hash.
6109    If using .MIPS.xhash, invoke record_xhash_symbol to add symbol index
6110    to the translation table.  */
6111 
6112 static bool
elf_gnu_hash_process_symidx(struct elf_link_hash_entry * h,void * data)6113 elf_gnu_hash_process_symidx (struct elf_link_hash_entry *h, void *data)
6114 {
6115   struct collect_gnu_hash_codes *s = (struct collect_gnu_hash_codes *) data;
6116   unsigned long int bucket;
6117   unsigned long int val;
6118 
6119   /* Ignore indirect symbols.  */
6120   if (h->dynindx == -1)
6121     return true;
6122 
6123   /* Ignore also local symbols and undefined symbols.  */
6124   if (! (*s->bed->elf_hash_symbol) (h))
6125     {
6126       if (h->dynindx >= s->min_dynindx)
6127 	{
6128 	  if (s->bed->record_xhash_symbol != NULL)
6129 	    {
6130 	      (*s->bed->record_xhash_symbol) (h, 0);
6131 	      s->local_indx++;
6132 	    }
6133 	  else
6134 	    h->dynindx = s->local_indx++;
6135 	}
6136       return true;
6137     }
6138 
6139   bucket = s->hashval[h->dynindx] % s->bucketcount;
6140   val = (s->hashval[h->dynindx] >> s->shift1)
6141 	& ((s->maskbits >> s->shift1) - 1);
6142   s->bitmask[val] |= ((bfd_vma) 1) << (s->hashval[h->dynindx] & s->mask);
6143   s->bitmask[val]
6144     |= ((bfd_vma) 1) << ((s->hashval[h->dynindx] >> s->shift2) & s->mask);
6145   val = s->hashval[h->dynindx] & ~(unsigned long int) 1;
6146   if (s->counts[bucket] == 1)
6147     /* Last element terminates the chain.  */
6148     val |= 1;
6149   bfd_put_32 (s->output_bfd, val,
6150 	      s->contents + (s->indx[bucket] - s->symindx) * 4);
6151   --s->counts[bucket];
6152   if (s->bed->record_xhash_symbol != NULL)
6153     {
6154       bfd_vma xlat_loc = s->xlat + (s->indx[bucket]++ - s->symindx) * 4;
6155 
6156       (*s->bed->record_xhash_symbol) (h, xlat_loc);
6157     }
6158   else
6159     h->dynindx = s->indx[bucket]++;
6160   return true;
6161 }
6162 
6163 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section.  */
6164 
6165 bool
_bfd_elf_hash_symbol(struct elf_link_hash_entry * h)6166 _bfd_elf_hash_symbol (struct elf_link_hash_entry *h)
6167 {
6168   return !(h->forced_local
6169 	   || h->root.type == bfd_link_hash_undefined
6170 	   || h->root.type == bfd_link_hash_undefweak
6171 	   || ((h->root.type == bfd_link_hash_defined
6172 		|| h->root.type == bfd_link_hash_defweak)
6173 	       && h->root.u.def.section->output_section == NULL));
6174 }
6175 
6176 /* Array used to determine the number of hash table buckets to use
6177    based on the number of symbols there are.  If there are fewer than
6178    3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
6179    fewer than 37 we use 17 buckets, and so forth.  We never use more
6180    than 32771 buckets.  */
6181 
6182 static const size_t elf_buckets[] =
6183 {
6184   1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
6185   16411, 32771, 0
6186 };
6187 
6188 /* Compute bucket count for hashing table.  We do not use a static set
6189    of possible tables sizes anymore.  Instead we determine for all
6190    possible reasonable sizes of the table the outcome (i.e., the
6191    number of collisions etc) and choose the best solution.  The
6192    weighting functions are not too simple to allow the table to grow
6193    without bounds.  Instead one of the weighting factors is the size.
6194    Therefore the result is always a good payoff between few collisions
6195    (= short chain lengths) and table size.  */
6196 static size_t
compute_bucket_count(struct bfd_link_info * info ATTRIBUTE_UNUSED,unsigned long int * hashcodes ATTRIBUTE_UNUSED,unsigned long int nsyms,int gnu_hash)6197 compute_bucket_count (struct bfd_link_info *info ATTRIBUTE_UNUSED,
6198 		      unsigned long int *hashcodes ATTRIBUTE_UNUSED,
6199 		      unsigned long int nsyms,
6200 		      int gnu_hash)
6201 {
6202   size_t best_size = 0;
6203   unsigned long int i;
6204 
6205   /* We have a problem here.  The following code to optimize the table
6206      size requires an integer type with more the 32 bits.  If
6207      BFD_HOST_U_64_BIT is set we know about such a type.  */
6208 #ifdef BFD_HOST_U_64_BIT
6209   if (info->optimize)
6210     {
6211       size_t minsize;
6212       size_t maxsize;
6213       BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
6214       bfd *dynobj = elf_hash_table (info)->dynobj;
6215       size_t dynsymcount = elf_hash_table (info)->dynsymcount;
6216       const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
6217       unsigned long int *counts;
6218       bfd_size_type amt;
6219       unsigned int no_improvement_count = 0;
6220 
6221       /* Possible optimization parameters: if we have NSYMS symbols we say
6222 	 that the hashing table must at least have NSYMS/4 and at most
6223 	 2*NSYMS buckets.  */
6224       minsize = nsyms / 4;
6225       if (minsize == 0)
6226 	minsize = 1;
6227       best_size = maxsize = nsyms * 2;
6228       if (gnu_hash)
6229 	{
6230 	  if (minsize < 2)
6231 	    minsize = 2;
6232 	  if ((best_size & 31) == 0)
6233 	    ++best_size;
6234 	}
6235 
6236       /* Create array where we count the collisions in.  We must use bfd_malloc
6237 	 since the size could be large.  */
6238       amt = maxsize;
6239       amt *= sizeof (unsigned long int);
6240       counts = (unsigned long int *) bfd_malloc (amt);
6241       if (counts == NULL)
6242 	return 0;
6243 
6244       /* Compute the "optimal" size for the hash table.  The criteria is a
6245 	 minimal chain length.  The minor criteria is (of course) the size
6246 	 of the table.  */
6247       for (i = minsize; i < maxsize; ++i)
6248 	{
6249 	  /* Walk through the array of hashcodes and count the collisions.  */
6250 	  BFD_HOST_U_64_BIT max;
6251 	  unsigned long int j;
6252 	  unsigned long int fact;
6253 
6254 	  if (gnu_hash && (i & 31) == 0)
6255 	    continue;
6256 
6257 	  memset (counts, '\0', i * sizeof (unsigned long int));
6258 
6259 	  /* Determine how often each hash bucket is used.  */
6260 	  for (j = 0; j < nsyms; ++j)
6261 	    ++counts[hashcodes[j] % i];
6262 
6263 	  /* For the weight function we need some information about the
6264 	     pagesize on the target.  This is information need not be 100%
6265 	     accurate.  Since this information is not available (so far) we
6266 	     define it here to a reasonable default value.  If it is crucial
6267 	     to have a better value some day simply define this value.  */
6268 # ifndef BFD_TARGET_PAGESIZE
6269 #  define BFD_TARGET_PAGESIZE	(4096)
6270 # endif
6271 
6272 	  /* We in any case need 2 + DYNSYMCOUNT entries for the size values
6273 	     and the chains.  */
6274 	  max = (2 + dynsymcount) * bed->s->sizeof_hash_entry;
6275 
6276 # if 1
6277 	  /* Variant 1: optimize for short chains.  We add the squares
6278 	     of all the chain lengths (which favors many small chain
6279 	     over a few long chains).  */
6280 	  for (j = 0; j < i; ++j)
6281 	    max += counts[j] * counts[j];
6282 
6283 	  /* This adds penalties for the overall size of the table.  */
6284 	  fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
6285 	  max *= fact * fact;
6286 # else
6287 	  /* Variant 2: Optimize a lot more for small table.  Here we
6288 	     also add squares of the size but we also add penalties for
6289 	     empty slots (the +1 term).  */
6290 	  for (j = 0; j < i; ++j)
6291 	    max += (1 + counts[j]) * (1 + counts[j]);
6292 
6293 	  /* The overall size of the table is considered, but not as
6294 	     strong as in variant 1, where it is squared.  */
6295 	  fact = i / (BFD_TARGET_PAGESIZE / bed->s->sizeof_hash_entry) + 1;
6296 	  max *= fact;
6297 # endif
6298 
6299 	  /* Compare with current best results.  */
6300 	  if (max < best_chlen)
6301 	    {
6302 	      best_chlen = max;
6303 	      best_size = i;
6304 	      no_improvement_count = 0;
6305 	    }
6306 	  /* PR 11843: Avoid futile long searches for the best bucket size
6307 	     when there are a large number of symbols.  */
6308 	  else if (++no_improvement_count == 100)
6309 	    break;
6310 	}
6311 
6312       free (counts);
6313     }
6314   else
6315 #endif /* defined (BFD_HOST_U_64_BIT) */
6316     {
6317       /* This is the fallback solution if no 64bit type is available or if we
6318 	 are not supposed to spend much time on optimizations.  We select the
6319 	 bucket count using a fixed set of numbers.  */
6320       for (i = 0; elf_buckets[i] != 0; i++)
6321 	{
6322 	  best_size = elf_buckets[i];
6323 	  if (nsyms < elf_buckets[i + 1])
6324 	    break;
6325 	}
6326       if (gnu_hash && best_size < 2)
6327 	best_size = 2;
6328     }
6329 
6330   return best_size;
6331 }
6332 
6333 /* Size any SHT_GROUP section for ld -r.  */
6334 
6335 bool
_bfd_elf_size_group_sections(struct bfd_link_info * info)6336 _bfd_elf_size_group_sections (struct bfd_link_info *info)
6337 {
6338   bfd *ibfd;
6339   asection *s;
6340 
6341   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
6342     if (bfd_get_flavour (ibfd) == bfd_target_elf_flavour
6343 	&& (s = ibfd->sections) != NULL
6344 	&& s->sec_info_type != SEC_INFO_TYPE_JUST_SYMS
6345 	&& !_bfd_elf_fixup_group_sections (ibfd, bfd_abs_section_ptr))
6346       return false;
6347   return true;
6348 }
6349 
6350 /* Set a default stack segment size.  The value in INFO wins.  If it
6351    is unset, LEGACY_SYMBOL's value is used, and if that symbol is
6352    undefined it is initialized.  */
6353 
6354 bool
bfd_elf_stack_segment_size(bfd * output_bfd,struct bfd_link_info * info,const char * legacy_symbol,bfd_vma default_size)6355 bfd_elf_stack_segment_size (bfd *output_bfd,
6356 			    struct bfd_link_info *info,
6357 			    const char *legacy_symbol,
6358 			    bfd_vma default_size)
6359 {
6360   struct elf_link_hash_entry *h = NULL;
6361 
6362   /* Look for legacy symbol.  */
6363   if (legacy_symbol)
6364     h = elf_link_hash_lookup (elf_hash_table (info), legacy_symbol,
6365 			      false, false, false);
6366   if (h && (h->root.type == bfd_link_hash_defined
6367 	    || h->root.type == bfd_link_hash_defweak)
6368       && h->def_regular
6369       && (h->type == STT_NOTYPE || h->type == STT_OBJECT))
6370     {
6371       /* The symbol has no type if specified on the command line.  */
6372       h->type = STT_OBJECT;
6373       if (info->stacksize)
6374 	/* xgettext:c-format */
6375 	_bfd_error_handler (_("%pB: stack size specified and %s set"),
6376 			    output_bfd, legacy_symbol);
6377       else if (h->root.u.def.section != bfd_abs_section_ptr)
6378 	/* xgettext:c-format */
6379 	_bfd_error_handler (_("%pB: %s not absolute"),
6380 			    output_bfd, legacy_symbol);
6381       else
6382 	info->stacksize = h->root.u.def.value;
6383     }
6384 
6385   if (!info->stacksize)
6386     /* If the user didn't set a size, or explicitly inhibit the
6387        size, set it now.  */
6388     info->stacksize = default_size;
6389 
6390   /* Provide the legacy symbol, if it is referenced.  */
6391   if (h && (h->root.type == bfd_link_hash_undefined
6392 	    || h->root.type == bfd_link_hash_undefweak))
6393     {
6394       struct bfd_link_hash_entry *bh = NULL;
6395 
6396       if (!(_bfd_generic_link_add_one_symbol
6397 	    (info, output_bfd, legacy_symbol,
6398 	     BSF_GLOBAL, bfd_abs_section_ptr,
6399 	     info->stacksize >= 0 ? info->stacksize : 0,
6400 	     NULL, false, get_elf_backend_data (output_bfd)->collect, &bh)))
6401 	return false;
6402 
6403       h = (struct elf_link_hash_entry *) bh;
6404       h->def_regular = 1;
6405       h->type = STT_OBJECT;
6406     }
6407 
6408   return true;
6409 }
6410 
6411 /* Sweep symbols in swept sections.  Called via elf_link_hash_traverse.  */
6412 
6413 struct elf_gc_sweep_symbol_info
6414 {
6415   struct bfd_link_info *info;
6416   void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
6417 		       bool);
6418 };
6419 
6420 static bool
elf_gc_sweep_symbol(struct elf_link_hash_entry * h,void * data)6421 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
6422 {
6423   if (!h->mark
6424       && (((h->root.type == bfd_link_hash_defined
6425 	    || h->root.type == bfd_link_hash_defweak)
6426 	   && !((h->def_regular || ELF_COMMON_DEF_P (h))
6427 		&& h->root.u.def.section->gc_mark))
6428 	  || h->root.type == bfd_link_hash_undefined
6429 	  || h->root.type == bfd_link_hash_undefweak))
6430     {
6431       struct elf_gc_sweep_symbol_info *inf;
6432 
6433       inf = (struct elf_gc_sweep_symbol_info *) data;
6434       (*inf->hide_symbol) (inf->info, h, true);
6435       h->def_regular = 0;
6436       h->ref_regular = 0;
6437       h->ref_regular_nonweak = 0;
6438     }
6439 
6440   return true;
6441 }
6442 
6443 /* Set up the sizes and contents of the ELF dynamic sections.  This is
6444    called by the ELF linker emulation before_allocation routine.  We
6445    must set the sizes of the sections before the linker sets the
6446    addresses of the various sections.  */
6447 
6448 bool
bfd_elf_size_dynamic_sections(bfd * output_bfd,const char * soname,const char * rpath,const char * filter_shlib,const char * audit,const char * depaudit,const char * const * auxiliary_filters,struct bfd_link_info * info,asection ** sinterpptr)6449 bfd_elf_size_dynamic_sections (bfd *output_bfd,
6450 			       const char *soname,
6451 			       const char *rpath,
6452 			       const char *filter_shlib,
6453 			       const char *audit,
6454 			       const char *depaudit,
6455 			       const char * const *auxiliary_filters,
6456 			       struct bfd_link_info *info,
6457 			       asection **sinterpptr)
6458 {
6459   bfd *dynobj;
6460   const struct elf_backend_data *bed;
6461 
6462   *sinterpptr = NULL;
6463 
6464   if (!is_elf_hash_table (info->hash))
6465     return true;
6466 
6467   dynobj = elf_hash_table (info)->dynobj;
6468 
6469   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
6470     {
6471       struct bfd_elf_version_tree *verdefs;
6472       struct elf_info_failed asvinfo;
6473       struct bfd_elf_version_tree *t;
6474       struct bfd_elf_version_expr *d;
6475       asection *s;
6476       size_t soname_indx;
6477 
6478       /* If we are supposed to export all symbols into the dynamic symbol
6479 	 table (this is not the normal case), then do so.  */
6480       if (info->export_dynamic
6481 	  || (bfd_link_executable (info) && info->dynamic))
6482 	{
6483 	  struct elf_info_failed eif;
6484 
6485 	  eif.info = info;
6486 	  eif.failed = false;
6487 	  elf_link_hash_traverse (elf_hash_table (info),
6488 				  _bfd_elf_export_symbol,
6489 				  &eif);
6490 	  if (eif.failed)
6491 	    return false;
6492 	}
6493 
6494       if (soname != NULL)
6495 	{
6496 	  soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6497 					     soname, true);
6498 	  if (soname_indx == (size_t) -1
6499 	      || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
6500 	    return false;
6501 	}
6502       else
6503 	soname_indx = (size_t) -1;
6504 
6505       /* Make all global versions with definition.  */
6506       for (t = info->version_info; t != NULL; t = t->next)
6507 	for (d = t->globals.list; d != NULL; d = d->next)
6508 	  if (!d->symver && d->literal)
6509 	    {
6510 	      const char *verstr, *name;
6511 	      size_t namelen, verlen, newlen;
6512 	      char *newname, *p, leading_char;
6513 	      struct elf_link_hash_entry *newh;
6514 
6515 	      leading_char = bfd_get_symbol_leading_char (output_bfd);
6516 	      name = d->pattern;
6517 	      namelen = strlen (name) + (leading_char != '\0');
6518 	      verstr = t->name;
6519 	      verlen = strlen (verstr);
6520 	      newlen = namelen + verlen + 3;
6521 
6522 	      newname = (char *) bfd_malloc (newlen);
6523 	      if (newname == NULL)
6524 		return false;
6525 	      newname[0] = leading_char;
6526 	      memcpy (newname + (leading_char != '\0'), name, namelen);
6527 
6528 	      /* Check the hidden versioned definition.  */
6529 	      p = newname + namelen;
6530 	      *p++ = ELF_VER_CHR;
6531 	      memcpy (p, verstr, verlen + 1);
6532 	      newh = elf_link_hash_lookup (elf_hash_table (info),
6533 					   newname, false, false,
6534 					   false);
6535 	      if (newh == NULL
6536 		  || (newh->root.type != bfd_link_hash_defined
6537 		      && newh->root.type != bfd_link_hash_defweak))
6538 		{
6539 		  /* Check the default versioned definition.  */
6540 		  *p++ = ELF_VER_CHR;
6541 		  memcpy (p, verstr, verlen + 1);
6542 		  newh = elf_link_hash_lookup (elf_hash_table (info),
6543 					       newname, false, false,
6544 					       false);
6545 		}
6546 	      free (newname);
6547 
6548 	      /* Mark this version if there is a definition and it is
6549 		 not defined in a shared object.  */
6550 	      if (newh != NULL
6551 		  && !newh->def_dynamic
6552 		  && (newh->root.type == bfd_link_hash_defined
6553 		      || newh->root.type == bfd_link_hash_defweak))
6554 		d->symver = 1;
6555 	    }
6556 
6557       /* Attach all the symbols to their version information.  */
6558       asvinfo.info = info;
6559       asvinfo.failed = false;
6560 
6561       elf_link_hash_traverse (elf_hash_table (info),
6562 			      _bfd_elf_link_assign_sym_version,
6563 			      &asvinfo);
6564       if (asvinfo.failed)
6565 	return false;
6566 
6567       if (!info->allow_undefined_version)
6568 	{
6569 	  /* Check if all global versions have a definition.  */
6570 	  bool all_defined = true;
6571 	  for (t = info->version_info; t != NULL; t = t->next)
6572 	    for (d = t->globals.list; d != NULL; d = d->next)
6573 	      if (d->literal && !d->symver && !d->script)
6574 		{
6575 		  _bfd_error_handler
6576 		    (_("%s: undefined version: %s"),
6577 		     d->pattern, t->name);
6578 		  all_defined = false;
6579 		}
6580 
6581 	  if (!all_defined)
6582 	    {
6583 	      bfd_set_error (bfd_error_bad_value);
6584 	      return false;
6585 	    }
6586 	}
6587 
6588       /* Set up the version definition section.  */
6589       s = bfd_get_linker_section (dynobj, ".gnu.version_d");
6590       BFD_ASSERT (s != NULL);
6591 
6592       /* We may have created additional version definitions if we are
6593 	 just linking a regular application.  */
6594       verdefs = info->version_info;
6595 
6596       /* Skip anonymous version tag.  */
6597       if (verdefs != NULL && verdefs->vernum == 0)
6598 	verdefs = verdefs->next;
6599 
6600       if (verdefs == NULL && !info->create_default_symver)
6601 	s->flags |= SEC_EXCLUDE;
6602       else
6603 	{
6604 	  unsigned int cdefs;
6605 	  bfd_size_type size;
6606 	  bfd_byte *p;
6607 	  Elf_Internal_Verdef def;
6608 	  Elf_Internal_Verdaux defaux;
6609 	  struct bfd_link_hash_entry *bh;
6610 	  struct elf_link_hash_entry *h;
6611 	  const char *name;
6612 
6613 	  cdefs = 0;
6614 	  size = 0;
6615 
6616 	  /* Make space for the base version.  */
6617 	  size += sizeof (Elf_External_Verdef);
6618 	  size += sizeof (Elf_External_Verdaux);
6619 	  ++cdefs;
6620 
6621 	  /* Make space for the default version.  */
6622 	  if (info->create_default_symver)
6623 	    {
6624 	      size += sizeof (Elf_External_Verdef);
6625 	      ++cdefs;
6626 	    }
6627 
6628 	  for (t = verdefs; t != NULL; t = t->next)
6629 	    {
6630 	      struct bfd_elf_version_deps *n;
6631 
6632 	      /* Don't emit base version twice.  */
6633 	      if (t->vernum == 0)
6634 		continue;
6635 
6636 	      size += sizeof (Elf_External_Verdef);
6637 	      size += sizeof (Elf_External_Verdaux);
6638 	      ++cdefs;
6639 
6640 	      for (n = t->deps; n != NULL; n = n->next)
6641 		size += sizeof (Elf_External_Verdaux);
6642 	    }
6643 
6644 	  s->size = size;
6645 	  s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
6646 	  if (s->contents == NULL && s->size != 0)
6647 	    return false;
6648 
6649 	  /* Fill in the version definition section.  */
6650 
6651 	  p = s->contents;
6652 
6653 	  def.vd_version = VER_DEF_CURRENT;
6654 	  def.vd_flags = VER_FLG_BASE;
6655 	  def.vd_ndx = 1;
6656 	  def.vd_cnt = 1;
6657 	  if (info->create_default_symver)
6658 	    {
6659 	      def.vd_aux = 2 * sizeof (Elf_External_Verdef);
6660 	      def.vd_next = sizeof (Elf_External_Verdef);
6661 	    }
6662 	  else
6663 	    {
6664 	      def.vd_aux = sizeof (Elf_External_Verdef);
6665 	      def.vd_next = (sizeof (Elf_External_Verdef)
6666 			     + sizeof (Elf_External_Verdaux));
6667 	    }
6668 
6669 	  if (soname_indx != (size_t) -1)
6670 	    {
6671 	      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6672 				      soname_indx);
6673 	      def.vd_hash = bfd_elf_hash (soname);
6674 	      defaux.vda_name = soname_indx;
6675 	      name = soname;
6676 	    }
6677 	  else
6678 	    {
6679 	      size_t indx;
6680 
6681 	      name = lbasename (bfd_get_filename (output_bfd));
6682 	      def.vd_hash = bfd_elf_hash (name);
6683 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6684 					  name, false);
6685 	      if (indx == (size_t) -1)
6686 		return false;
6687 	      defaux.vda_name = indx;
6688 	    }
6689 	  defaux.vda_next = 0;
6690 
6691 	  _bfd_elf_swap_verdef_out (output_bfd, &def,
6692 				    (Elf_External_Verdef *) p);
6693 	  p += sizeof (Elf_External_Verdef);
6694 	  if (info->create_default_symver)
6695 	    {
6696 	      /* Add a symbol representing this version.  */
6697 	      bh = NULL;
6698 	      if (! (_bfd_generic_link_add_one_symbol
6699 		     (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
6700 		      0, NULL, false,
6701 		      get_elf_backend_data (dynobj)->collect, &bh)))
6702 		return false;
6703 	      h = (struct elf_link_hash_entry *) bh;
6704 	      h->non_elf = 0;
6705 	      h->def_regular = 1;
6706 	      h->type = STT_OBJECT;
6707 	      h->verinfo.vertree = NULL;
6708 
6709 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
6710 		return false;
6711 
6712 	      /* Create a duplicate of the base version with the same
6713 		 aux block, but different flags.  */
6714 	      def.vd_flags = 0;
6715 	      def.vd_ndx = 2;
6716 	      def.vd_aux = sizeof (Elf_External_Verdef);
6717 	      if (verdefs)
6718 		def.vd_next = (sizeof (Elf_External_Verdef)
6719 			       + sizeof (Elf_External_Verdaux));
6720 	      else
6721 		def.vd_next = 0;
6722 	      _bfd_elf_swap_verdef_out (output_bfd, &def,
6723 					(Elf_External_Verdef *) p);
6724 	      p += sizeof (Elf_External_Verdef);
6725 	    }
6726 	  _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6727 				     (Elf_External_Verdaux *) p);
6728 	  p += sizeof (Elf_External_Verdaux);
6729 
6730 	  for (t = verdefs; t != NULL; t = t->next)
6731 	    {
6732 	      unsigned int cdeps;
6733 	      struct bfd_elf_version_deps *n;
6734 
6735 	      /* Don't emit the base version twice.  */
6736 	      if (t->vernum == 0)
6737 		continue;
6738 
6739 	      cdeps = 0;
6740 	      for (n = t->deps; n != NULL; n = n->next)
6741 		++cdeps;
6742 
6743 	      /* Add a symbol representing this version.  */
6744 	      bh = NULL;
6745 	      if (! (_bfd_generic_link_add_one_symbol
6746 		     (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
6747 		      0, NULL, false,
6748 		      get_elf_backend_data (dynobj)->collect, &bh)))
6749 		return false;
6750 	      h = (struct elf_link_hash_entry *) bh;
6751 	      h->non_elf = 0;
6752 	      h->def_regular = 1;
6753 	      h->type = STT_OBJECT;
6754 	      h->verinfo.vertree = t;
6755 
6756 	      if (! bfd_elf_link_record_dynamic_symbol (info, h))
6757 		return false;
6758 
6759 	      def.vd_version = VER_DEF_CURRENT;
6760 	      def.vd_flags = 0;
6761 	      if (t->globals.list == NULL
6762 		  && t->locals.list == NULL
6763 		  && ! t->used)
6764 		def.vd_flags |= VER_FLG_WEAK;
6765 	      def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
6766 	      def.vd_cnt = cdeps + 1;
6767 	      def.vd_hash = bfd_elf_hash (t->name);
6768 	      def.vd_aux = sizeof (Elf_External_Verdef);
6769 	      def.vd_next = 0;
6770 
6771 	      /* If a basever node is next, it *must* be the last node in
6772 		 the chain, otherwise Verdef construction breaks.  */
6773 	      if (t->next != NULL && t->next->vernum == 0)
6774 		BFD_ASSERT (t->next->next == NULL);
6775 
6776 	      if (t->next != NULL && t->next->vernum != 0)
6777 		def.vd_next = (sizeof (Elf_External_Verdef)
6778 			       + (cdeps + 1) * sizeof (Elf_External_Verdaux));
6779 
6780 	      _bfd_elf_swap_verdef_out (output_bfd, &def,
6781 					(Elf_External_Verdef *) p);
6782 	      p += sizeof (Elf_External_Verdef);
6783 
6784 	      defaux.vda_name = h->dynstr_index;
6785 	      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6786 				      h->dynstr_index);
6787 	      defaux.vda_next = 0;
6788 	      if (t->deps != NULL)
6789 		defaux.vda_next = sizeof (Elf_External_Verdaux);
6790 	      t->name_indx = defaux.vda_name;
6791 
6792 	      _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6793 					 (Elf_External_Verdaux *) p);
6794 	      p += sizeof (Elf_External_Verdaux);
6795 
6796 	      for (n = t->deps; n != NULL; n = n->next)
6797 		{
6798 		  if (n->version_needed == NULL)
6799 		    {
6800 		      /* This can happen if there was an error in the
6801 			 version script.  */
6802 		      defaux.vda_name = 0;
6803 		    }
6804 		  else
6805 		    {
6806 		      defaux.vda_name = n->version_needed->name_indx;
6807 		      _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
6808 					      defaux.vda_name);
6809 		    }
6810 		  if (n->next == NULL)
6811 		    defaux.vda_next = 0;
6812 		  else
6813 		    defaux.vda_next = sizeof (Elf_External_Verdaux);
6814 
6815 		  _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
6816 					     (Elf_External_Verdaux *) p);
6817 		  p += sizeof (Elf_External_Verdaux);
6818 		}
6819 	    }
6820 
6821 	  elf_tdata (output_bfd)->cverdefs = cdefs;
6822 	}
6823     }
6824 
6825   bed = get_elf_backend_data (output_bfd);
6826 
6827   if (info->gc_sections && bed->can_gc_sections)
6828     {
6829       struct elf_gc_sweep_symbol_info sweep_info;
6830 
6831       /* Remove the symbols that were in the swept sections from the
6832 	 dynamic symbol table.  */
6833       sweep_info.info = info;
6834       sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
6835       elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
6836 			      &sweep_info);
6837     }
6838 
6839   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
6840     {
6841       asection *s;
6842       struct elf_find_verdep_info sinfo;
6843 
6844       /* Work out the size of the version reference section.  */
6845 
6846       s = bfd_get_linker_section (dynobj, ".gnu.version_r");
6847       BFD_ASSERT (s != NULL);
6848 
6849       sinfo.info = info;
6850       sinfo.vers = elf_tdata (output_bfd)->cverdefs;
6851       if (sinfo.vers == 0)
6852 	sinfo.vers = 1;
6853       sinfo.failed = false;
6854 
6855       elf_link_hash_traverse (elf_hash_table (info),
6856 			      _bfd_elf_link_find_version_dependencies,
6857 			      &sinfo);
6858       if (sinfo.failed)
6859 	return false;
6860 
6861       if (elf_tdata (output_bfd)->verref == NULL)
6862 	s->flags |= SEC_EXCLUDE;
6863       else
6864 	{
6865 	  Elf_Internal_Verneed *vn;
6866 	  unsigned int size;
6867 	  unsigned int crefs;
6868 	  bfd_byte *p;
6869 
6870 	  /* Build the version dependency section.  */
6871 	  size = 0;
6872 	  crefs = 0;
6873 	  for (vn = elf_tdata (output_bfd)->verref;
6874 	       vn != NULL;
6875 	       vn = vn->vn_nextref)
6876 	    {
6877 	      Elf_Internal_Vernaux *a;
6878 
6879 	      size += sizeof (Elf_External_Verneed);
6880 	      ++crefs;
6881 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
6882 		size += sizeof (Elf_External_Vernaux);
6883 	    }
6884 
6885 	  s->size = size;
6886 	  s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
6887 	  if (s->contents == NULL)
6888 	    return false;
6889 
6890 	  p = s->contents;
6891 	  for (vn = elf_tdata (output_bfd)->verref;
6892 	       vn != NULL;
6893 	       vn = vn->vn_nextref)
6894 	    {
6895 	      unsigned int caux;
6896 	      Elf_Internal_Vernaux *a;
6897 	      size_t indx;
6898 
6899 	      caux = 0;
6900 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
6901 		++caux;
6902 
6903 	      vn->vn_version = VER_NEED_CURRENT;
6904 	      vn->vn_cnt = caux;
6905 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6906 					  elf_dt_name (vn->vn_bfd) != NULL
6907 					  ? elf_dt_name (vn->vn_bfd)
6908 					  : lbasename (bfd_get_filename
6909 						       (vn->vn_bfd)),
6910 					  false);
6911 	      if (indx == (size_t) -1)
6912 		return false;
6913 	      vn->vn_file = indx;
6914 	      vn->vn_aux = sizeof (Elf_External_Verneed);
6915 	      if (vn->vn_nextref == NULL)
6916 		vn->vn_next = 0;
6917 	      else
6918 		vn->vn_next = (sizeof (Elf_External_Verneed)
6919 			       + caux * sizeof (Elf_External_Vernaux));
6920 
6921 	      _bfd_elf_swap_verneed_out (output_bfd, vn,
6922 					 (Elf_External_Verneed *) p);
6923 	      p += sizeof (Elf_External_Verneed);
6924 
6925 	      for (a = vn->vn_auxptr; a != NULL; a = a->vna_nextptr)
6926 		{
6927 		  a->vna_hash = bfd_elf_hash (a->vna_nodename);
6928 		  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
6929 					      a->vna_nodename, false);
6930 		  if (indx == (size_t) -1)
6931 		    return false;
6932 		  a->vna_name = indx;
6933 		  if (a->vna_nextptr == NULL)
6934 		    a->vna_next = 0;
6935 		  else
6936 		    a->vna_next = sizeof (Elf_External_Vernaux);
6937 
6938 		  _bfd_elf_swap_vernaux_out (output_bfd, a,
6939 					     (Elf_External_Vernaux *) p);
6940 		  p += sizeof (Elf_External_Vernaux);
6941 		}
6942 	    }
6943 
6944 	  elf_tdata (output_bfd)->cverrefs = crefs;
6945 	}
6946     }
6947 
6948   /* Any syms created from now on start with -1 in
6949      got.refcount/offset and plt.refcount/offset.  */
6950   elf_hash_table (info)->init_got_refcount
6951     = elf_hash_table (info)->init_got_offset;
6952   elf_hash_table (info)->init_plt_refcount
6953     = elf_hash_table (info)->init_plt_offset;
6954 
6955   if (bfd_link_relocatable (info)
6956       && !_bfd_elf_size_group_sections (info))
6957     return false;
6958 
6959   /* The backend may have to create some sections regardless of whether
6960      we're dynamic or not.  */
6961   if (bed->elf_backend_always_size_sections
6962       && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
6963     return false;
6964 
6965   /* Determine any GNU_STACK segment requirements, after the backend
6966      has had a chance to set a default segment size.  */
6967   if (info->execstack)
6968     elf_stack_flags (output_bfd) = PF_R | PF_W | PF_X;
6969   else if (info->noexecstack)
6970     elf_stack_flags (output_bfd) = PF_R | PF_W;
6971   else
6972     {
6973       bfd *inputobj;
6974       asection *notesec = NULL;
6975       int exec = 0;
6976 
6977       for (inputobj = info->input_bfds;
6978 	   inputobj;
6979 	   inputobj = inputobj->link.next)
6980 	{
6981 	  asection *s;
6982 
6983 	  if (inputobj->flags
6984 	      & (DYNAMIC | EXEC_P | BFD_PLUGIN | BFD_LINKER_CREATED))
6985 	    continue;
6986 	  s = inputobj->sections;
6987 	  if (s == NULL || s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
6988 	    continue;
6989 
6990 	  s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
6991 	  if (s)
6992 	    {
6993 	      if (s->flags & SEC_CODE)
6994 		exec = PF_X;
6995 	      notesec = s;
6996 	    }
6997 	  else if (bed->default_execstack)
6998 	    exec = PF_X;
6999 	}
7000       if (notesec || info->stacksize > 0)
7001 	elf_stack_flags (output_bfd) = PF_R | PF_W | exec;
7002       if (notesec && exec && bfd_link_relocatable (info)
7003 	  && notesec->output_section != bfd_abs_section_ptr)
7004 	notesec->output_section->flags |= SEC_CODE;
7005     }
7006 
7007   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
7008     {
7009       struct elf_info_failed eif;
7010       struct elf_link_hash_entry *h;
7011       asection *dynstr;
7012       asection *s;
7013 
7014       *sinterpptr = bfd_get_linker_section (dynobj, ".interp");
7015       BFD_ASSERT (*sinterpptr != NULL || !bfd_link_executable (info) || info->nointerp);
7016 
7017       if (info->symbolic)
7018 	{
7019 	  if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
7020 	    return false;
7021 	  info->flags |= DF_SYMBOLIC;
7022 	}
7023 
7024       if (rpath != NULL)
7025 	{
7026 	  size_t indx;
7027 	  bfd_vma tag;
7028 
7029 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
7030 				      true);
7031 	  if (indx == (size_t) -1)
7032 	    return false;
7033 
7034 	  tag = info->new_dtags ? DT_RUNPATH : DT_RPATH;
7035 	  if (!_bfd_elf_add_dynamic_entry (info, tag, indx))
7036 	    return false;
7037 	}
7038 
7039       if (filter_shlib != NULL)
7040 	{
7041 	  size_t indx;
7042 
7043 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7044 				      filter_shlib, true);
7045 	  if (indx == (size_t) -1
7046 	      || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
7047 	    return false;
7048 	}
7049 
7050       if (auxiliary_filters != NULL)
7051 	{
7052 	  const char * const *p;
7053 
7054 	  for (p = auxiliary_filters; *p != NULL; p++)
7055 	    {
7056 	      size_t indx;
7057 
7058 	      indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
7059 					  *p, true);
7060 	      if (indx == (size_t) -1
7061 		  || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
7062 		return false;
7063 	    }
7064 	}
7065 
7066       if (audit != NULL)
7067 	{
7068 	  size_t indx;
7069 
7070 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, audit,
7071 				      true);
7072 	  if (indx == (size_t) -1
7073 	      || !_bfd_elf_add_dynamic_entry (info, DT_AUDIT, indx))
7074 	    return false;
7075 	}
7076 
7077       if (depaudit != NULL)
7078 	{
7079 	  size_t indx;
7080 
7081 	  indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, depaudit,
7082 				      true);
7083 	  if (indx == (size_t) -1
7084 	      || !_bfd_elf_add_dynamic_entry (info, DT_DEPAUDIT, indx))
7085 	    return false;
7086 	}
7087 
7088       eif.info = info;
7089       eif.failed = false;
7090 
7091       /* Find all symbols which were defined in a dynamic object and make
7092 	 the backend pick a reasonable value for them.  */
7093       elf_link_hash_traverse (elf_hash_table (info),
7094 			      _bfd_elf_adjust_dynamic_symbol,
7095 			      &eif);
7096       if (eif.failed)
7097 	return false;
7098 
7099       /* Add some entries to the .dynamic section.  We fill in some of the
7100 	 values later, in bfd_elf_final_link, but we must add the entries
7101 	 now so that we know the final size of the .dynamic section.  */
7102 
7103       /* If there are initialization and/or finalization functions to
7104 	 call then add the corresponding DT_INIT/DT_FINI entries.  */
7105       h = (info->init_function
7106 	   ? elf_link_hash_lookup (elf_hash_table (info),
7107 				   info->init_function, false,
7108 				   false, false)
7109 	   : NULL);
7110       if (h != NULL
7111 	  && (h->ref_regular
7112 	      || h->def_regular))
7113 	{
7114 	  if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
7115 	    return false;
7116 	}
7117       h = (info->fini_function
7118 	   ? elf_link_hash_lookup (elf_hash_table (info),
7119 				   info->fini_function, false,
7120 				   false, false)
7121 	   : NULL);
7122       if (h != NULL
7123 	  && (h->ref_regular
7124 	      || h->def_regular))
7125 	{
7126 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
7127 	    return false;
7128 	}
7129 
7130       s = bfd_get_section_by_name (output_bfd, ".preinit_array");
7131       if (s != NULL && s->linker_has_input)
7132 	{
7133 	  /* DT_PREINIT_ARRAY is not allowed in shared library.  */
7134 	  if (! bfd_link_executable (info))
7135 	    {
7136 	      bfd *sub;
7137 	      asection *o;
7138 
7139 	      for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
7140 		if (bfd_get_flavour (sub) == bfd_target_elf_flavour
7141 		    && (o = sub->sections) != NULL
7142 		    && o->sec_info_type != SEC_INFO_TYPE_JUST_SYMS)
7143 		  for (o = sub->sections; o != NULL; o = o->next)
7144 		    if (elf_section_data (o)->this_hdr.sh_type
7145 			== SHT_PREINIT_ARRAY)
7146 		      {
7147 			_bfd_error_handler
7148 			  (_("%pB: .preinit_array section is not allowed in DSO"),
7149 			   sub);
7150 			break;
7151 		      }
7152 
7153 	      bfd_set_error (bfd_error_nonrepresentable_section);
7154 	      return false;
7155 	    }
7156 
7157 	  if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
7158 	      || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
7159 	    return false;
7160 	}
7161       s = bfd_get_section_by_name (output_bfd, ".init_array");
7162       if (s != NULL && s->linker_has_input)
7163 	{
7164 	  if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
7165 	      || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
7166 	    return false;
7167 	}
7168       s = bfd_get_section_by_name (output_bfd, ".fini_array");
7169       if (s != NULL && s->linker_has_input)
7170 	{
7171 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
7172 	      || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
7173 	    return false;
7174 	}
7175 
7176       dynstr = bfd_get_linker_section (dynobj, ".dynstr");
7177       /* If .dynstr is excluded from the link, we don't want any of
7178 	 these tags.  Strictly, we should be checking each section
7179 	 individually;  This quick check covers for the case where
7180 	 someone does a /DISCARD/ : { *(*) }.  */
7181       if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
7182 	{
7183 	  bfd_size_type strsize;
7184 
7185 	  strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
7186 	  if ((info->emit_hash
7187 	       && !_bfd_elf_add_dynamic_entry (info, DT_HASH, 0))
7188 	      || (info->emit_gnu_hash
7189 		  && (bed->record_xhash_symbol == NULL
7190 		      && !_bfd_elf_add_dynamic_entry (info, DT_GNU_HASH, 0)))
7191 	      || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
7192 	      || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
7193 	      || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
7194 	      || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
7195 					      bed->s->sizeof_sym)
7196 	      || (info->gnu_flags_1
7197 		  && !_bfd_elf_add_dynamic_entry (info, DT_GNU_FLAGS_1,
7198 						  info->gnu_flags_1)))
7199 	    return false;
7200 	}
7201     }
7202 
7203   if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
7204     return false;
7205 
7206   /* The backend must work out the sizes of all the other dynamic
7207      sections.  */
7208   if (dynobj != NULL
7209       && bed->elf_backend_size_dynamic_sections != NULL
7210       && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
7211     return false;
7212 
7213   if (dynobj != NULL && elf_hash_table (info)->dynamic_sections_created)
7214     {
7215       if (elf_tdata (output_bfd)->cverdefs)
7216 	{
7217 	  unsigned int crefs = elf_tdata (output_bfd)->cverdefs;
7218 
7219 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
7220 	      || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, crefs))
7221 	    return false;
7222 	}
7223 
7224       if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
7225 	{
7226 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
7227 	    return false;
7228 	}
7229       else if (info->flags & DF_BIND_NOW)
7230 	{
7231 	  if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
7232 	    return false;
7233 	}
7234 
7235       if (info->flags_1)
7236 	{
7237 	  if (bfd_link_executable (info))
7238 	    info->flags_1 &= ~ (DF_1_INITFIRST
7239 				| DF_1_NODELETE
7240 				| DF_1_NOOPEN);
7241 	  if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
7242 	    return false;
7243 	}
7244 
7245       if (elf_tdata (output_bfd)->cverrefs)
7246 	{
7247 	  unsigned int crefs = elf_tdata (output_bfd)->cverrefs;
7248 
7249 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
7250 	      || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
7251 	    return false;
7252 	}
7253 
7254       if ((elf_tdata (output_bfd)->cverrefs == 0
7255 	   && elf_tdata (output_bfd)->cverdefs == 0)
7256 	  || _bfd_elf_link_renumber_dynsyms (output_bfd, info, NULL) <= 1)
7257 	{
7258 	  asection *s;
7259 
7260 	  s = bfd_get_linker_section (dynobj, ".gnu.version");
7261 	  s->flags |= SEC_EXCLUDE;
7262 	}
7263     }
7264   return true;
7265 }
7266 
7267 /* Find the first non-excluded output section.  We'll use its
7268    section symbol for some emitted relocs.  */
7269 void
_bfd_elf_init_1_index_section(bfd * output_bfd,struct bfd_link_info * info)7270 _bfd_elf_init_1_index_section (bfd *output_bfd, struct bfd_link_info *info)
7271 {
7272   asection *s;
7273   asection *found = NULL;
7274 
7275   for (s = output_bfd->sections; s != NULL; s = s->next)
7276     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7277 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7278       {
7279 	found = s;
7280 	if ((s->flags & SEC_THREAD_LOCAL) == 0)
7281 	  break;
7282       }
7283   elf_hash_table (info)->text_index_section = found;
7284 }
7285 
7286 /* Find two non-excluded output sections, one for code, one for data.
7287    We'll use their section symbols for some emitted relocs.  */
7288 void
_bfd_elf_init_2_index_sections(bfd * output_bfd,struct bfd_link_info * info)7289 _bfd_elf_init_2_index_sections (bfd *output_bfd, struct bfd_link_info *info)
7290 {
7291   asection *s;
7292   asection *found = NULL;
7293 
7294   /* Data first, since setting text_index_section changes
7295      _bfd_elf_omit_section_dynsym_default.  */
7296   for (s = output_bfd->sections; s != NULL; s = s->next)
7297     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7298 	&& !(s->flags & SEC_READONLY)
7299 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7300       {
7301 	found = s;
7302 	if ((s->flags & SEC_THREAD_LOCAL) == 0)
7303 	  break;
7304       }
7305   elf_hash_table (info)->data_index_section = found;
7306 
7307   for (s = output_bfd->sections; s != NULL; s = s->next)
7308     if ((s->flags & (SEC_EXCLUDE | SEC_ALLOC)) == SEC_ALLOC
7309 	&& (s->flags & SEC_READONLY)
7310 	&& !_bfd_elf_omit_section_dynsym_default (output_bfd, info, s))
7311       {
7312 	found = s;
7313 	break;
7314       }
7315   elf_hash_table (info)->text_index_section = found;
7316 }
7317 
7318 #define GNU_HASH_SECTION_NAME(bed)			    \
7319   (bed)->record_xhash_symbol != NULL ? ".MIPS.xhash" : ".gnu.hash"
7320 
7321 bool
bfd_elf_size_dynsym_hash_dynstr(bfd * output_bfd,struct bfd_link_info * info)7322 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
7323 {
7324   const struct elf_backend_data *bed;
7325   unsigned long section_sym_count;
7326   bfd_size_type dynsymcount = 0;
7327 
7328   if (!is_elf_hash_table (info->hash))
7329     return true;
7330 
7331   bed = get_elf_backend_data (output_bfd);
7332   (*bed->elf_backend_init_index_section) (output_bfd, info);
7333 
7334   /* Assign dynsym indices.  In a shared library we generate a section
7335      symbol for each output section, which come first.  Next come all
7336      of the back-end allocated local dynamic syms, followed by the rest
7337      of the global symbols.
7338 
7339      This is usually not needed for static binaries, however backends
7340      can request to always do it, e.g. the MIPS backend uses dynamic
7341      symbol counts to lay out GOT, which will be produced in the
7342      presence of GOT relocations even in static binaries (holding fixed
7343      data in that case, to satisfy those relocations).  */
7344 
7345   if (elf_hash_table (info)->dynamic_sections_created
7346       || bed->always_renumber_dynsyms)
7347     dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
7348 						  &section_sym_count);
7349 
7350   if (elf_hash_table (info)->dynamic_sections_created)
7351     {
7352       bfd *dynobj;
7353       asection *s;
7354       unsigned int dtagcount;
7355 
7356       dynobj = elf_hash_table (info)->dynobj;
7357 
7358       /* Work out the size of the symbol version section.  */
7359       s = bfd_get_linker_section (dynobj, ".gnu.version");
7360       BFD_ASSERT (s != NULL);
7361       if ((s->flags & SEC_EXCLUDE) == 0)
7362 	{
7363 	  s->size = dynsymcount * sizeof (Elf_External_Versym);
7364 	  s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7365 	  if (s->contents == NULL)
7366 	    return false;
7367 
7368 	  if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
7369 	    return false;
7370 	}
7371 
7372       /* Set the size of the .dynsym and .hash sections.  We counted
7373 	 the number of dynamic symbols in elf_link_add_object_symbols.
7374 	 We will build the contents of .dynsym and .hash when we build
7375 	 the final symbol table, because until then we do not know the
7376 	 correct value to give the symbols.  We built the .dynstr
7377 	 section as we went along in elf_link_add_object_symbols.  */
7378       s = elf_hash_table (info)->dynsym;
7379       BFD_ASSERT (s != NULL);
7380       s->size = dynsymcount * bed->s->sizeof_sym;
7381 
7382       s->contents = (unsigned char *) bfd_alloc (output_bfd, s->size);
7383       if (s->contents == NULL)
7384 	return false;
7385 
7386       /* The first entry in .dynsym is a dummy symbol.  Clear all the
7387 	 section syms, in case we don't output them all.  */
7388       ++section_sym_count;
7389       memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
7390 
7391       elf_hash_table (info)->bucketcount = 0;
7392 
7393       /* Compute the size of the hashing table.  As a side effect this
7394 	 computes the hash values for all the names we export.  */
7395       if (info->emit_hash)
7396 	{
7397 	  unsigned long int *hashcodes;
7398 	  struct hash_codes_info hashinf;
7399 	  bfd_size_type amt;
7400 	  unsigned long int nsyms;
7401 	  size_t bucketcount;
7402 	  size_t hash_entry_size;
7403 
7404 	  /* Compute the hash values for all exported symbols.  At the same
7405 	     time store the values in an array so that we could use them for
7406 	     optimizations.  */
7407 	  amt = dynsymcount * sizeof (unsigned long int);
7408 	  hashcodes = (unsigned long int *) bfd_malloc (amt);
7409 	  if (hashcodes == NULL)
7410 	    return false;
7411 	  hashinf.hashcodes = hashcodes;
7412 	  hashinf.error = false;
7413 
7414 	  /* Put all hash values in HASHCODES.  */
7415 	  elf_link_hash_traverse (elf_hash_table (info),
7416 				  elf_collect_hash_codes, &hashinf);
7417 	  if (hashinf.error)
7418 	    {
7419 	      free (hashcodes);
7420 	      return false;
7421 	    }
7422 
7423 	  nsyms = hashinf.hashcodes - hashcodes;
7424 	  bucketcount
7425 	    = compute_bucket_count (info, hashcodes, nsyms, 0);
7426 	  free (hashcodes);
7427 
7428 	  if (bucketcount == 0 && nsyms > 0)
7429 	    return false;
7430 
7431 	  elf_hash_table (info)->bucketcount = bucketcount;
7432 
7433 	  s = bfd_get_linker_section (dynobj, ".hash");
7434 	  BFD_ASSERT (s != NULL);
7435 	  hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
7436 	  s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
7437 	  s->contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7438 	  if (s->contents == NULL)
7439 	    return false;
7440 
7441 	  bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
7442 	  bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
7443 		   s->contents + hash_entry_size);
7444 	}
7445 
7446       if (info->emit_gnu_hash)
7447 	{
7448 	  size_t i, cnt;
7449 	  unsigned char *contents;
7450 	  struct collect_gnu_hash_codes cinfo;
7451 	  bfd_size_type amt;
7452 	  size_t bucketcount;
7453 
7454 	  memset (&cinfo, 0, sizeof (cinfo));
7455 
7456 	  /* Compute the hash values for all exported symbols.  At the same
7457 	     time store the values in an array so that we could use them for
7458 	     optimizations.  */
7459 	  amt = dynsymcount * 2 * sizeof (unsigned long int);
7460 	  cinfo.hashcodes = (long unsigned int *) bfd_malloc (amt);
7461 	  if (cinfo.hashcodes == NULL)
7462 	    return false;
7463 
7464 	  cinfo.hashval = cinfo.hashcodes + dynsymcount;
7465 	  cinfo.min_dynindx = -1;
7466 	  cinfo.output_bfd = output_bfd;
7467 	  cinfo.bed = bed;
7468 
7469 	  /* Put all hash values in HASHCODES.  */
7470 	  elf_link_hash_traverse (elf_hash_table (info),
7471 				  elf_collect_gnu_hash_codes, &cinfo);
7472 	  if (cinfo.error)
7473 	    {
7474 	      free (cinfo.hashcodes);
7475 	      return false;
7476 	    }
7477 
7478 	  bucketcount
7479 	    = compute_bucket_count (info, cinfo.hashcodes, cinfo.nsyms, 1);
7480 
7481 	  if (bucketcount == 0)
7482 	    {
7483 	      free (cinfo.hashcodes);
7484 	      return false;
7485 	    }
7486 
7487 	  s = bfd_get_linker_section (dynobj, GNU_HASH_SECTION_NAME (bed));
7488 	  BFD_ASSERT (s != NULL);
7489 
7490 	  if (cinfo.nsyms == 0)
7491 	    {
7492 	      /* Empty .gnu.hash or .MIPS.xhash section is special.  */
7493 	      BFD_ASSERT (cinfo.min_dynindx == -1);
7494 	      free (cinfo.hashcodes);
7495 	      s->size = 5 * 4 + bed->s->arch_size / 8;
7496 	      contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7497 	      if (contents == NULL)
7498 		return false;
7499 	      s->contents = contents;
7500 	      /* 1 empty bucket.  */
7501 	      bfd_put_32 (output_bfd, 1, contents);
7502 	      /* SYMIDX above the special symbol 0.  */
7503 	      bfd_put_32 (output_bfd, 1, contents + 4);
7504 	      /* Just one word for bitmask.  */
7505 	      bfd_put_32 (output_bfd, 1, contents + 8);
7506 	      /* Only hash fn bloom filter.  */
7507 	      bfd_put_32 (output_bfd, 0, contents + 12);
7508 	      /* No hashes are valid - empty bitmask.  */
7509 	      bfd_put (bed->s->arch_size, output_bfd, 0, contents + 16);
7510 	      /* No hashes in the only bucket.  */
7511 	      bfd_put_32 (output_bfd, 0,
7512 			  contents + 16 + bed->s->arch_size / 8);
7513 	    }
7514 	  else
7515 	    {
7516 	      unsigned long int maskwords, maskbitslog2, x;
7517 	      BFD_ASSERT (cinfo.min_dynindx != -1);
7518 
7519 	      x = cinfo.nsyms;
7520 	      maskbitslog2 = 1;
7521 	      while ((x >>= 1) != 0)
7522 		++maskbitslog2;
7523 	      if (maskbitslog2 < 3)
7524 		maskbitslog2 = 5;
7525 	      else if ((1 << (maskbitslog2 - 2)) & cinfo.nsyms)
7526 		maskbitslog2 = maskbitslog2 + 3;
7527 	      else
7528 		maskbitslog2 = maskbitslog2 + 2;
7529 	      if (bed->s->arch_size == 64)
7530 		{
7531 		  if (maskbitslog2 == 5)
7532 		    maskbitslog2 = 6;
7533 		  cinfo.shift1 = 6;
7534 		}
7535 	      else
7536 		cinfo.shift1 = 5;
7537 	      cinfo.mask = (1 << cinfo.shift1) - 1;
7538 	      cinfo.shift2 = maskbitslog2;
7539 	      cinfo.maskbits = 1 << maskbitslog2;
7540 	      maskwords = 1 << (maskbitslog2 - cinfo.shift1);
7541 	      amt = bucketcount * sizeof (unsigned long int) * 2;
7542 	      amt += maskwords * sizeof (bfd_vma);
7543 	      cinfo.bitmask = (bfd_vma *) bfd_malloc (amt);
7544 	      if (cinfo.bitmask == NULL)
7545 		{
7546 		  free (cinfo.hashcodes);
7547 		  return false;
7548 		}
7549 
7550 	      cinfo.counts = (long unsigned int *) (cinfo.bitmask + maskwords);
7551 	      cinfo.indx = cinfo.counts + bucketcount;
7552 	      cinfo.symindx = dynsymcount - cinfo.nsyms;
7553 	      memset (cinfo.bitmask, 0, maskwords * sizeof (bfd_vma));
7554 
7555 	      /* Determine how often each hash bucket is used.  */
7556 	      memset (cinfo.counts, 0, bucketcount * sizeof (cinfo.counts[0]));
7557 	      for (i = 0; i < cinfo.nsyms; ++i)
7558 		++cinfo.counts[cinfo.hashcodes[i] % bucketcount];
7559 
7560 	      for (i = 0, cnt = cinfo.symindx; i < bucketcount; ++i)
7561 		if (cinfo.counts[i] != 0)
7562 		  {
7563 		    cinfo.indx[i] = cnt;
7564 		    cnt += cinfo.counts[i];
7565 		  }
7566 	      BFD_ASSERT (cnt == dynsymcount);
7567 	      cinfo.bucketcount = bucketcount;
7568 	      cinfo.local_indx = cinfo.min_dynindx;
7569 
7570 	      s->size = (4 + bucketcount + cinfo.nsyms) * 4;
7571 	      s->size += cinfo.maskbits / 8;
7572 	      if (bed->record_xhash_symbol != NULL)
7573 		s->size += cinfo.nsyms * 4;
7574 	      contents = (unsigned char *) bfd_zalloc (output_bfd, s->size);
7575 	      if (contents == NULL)
7576 		{
7577 		  free (cinfo.bitmask);
7578 		  free (cinfo.hashcodes);
7579 		  return false;
7580 		}
7581 
7582 	      s->contents = contents;
7583 	      bfd_put_32 (output_bfd, bucketcount, contents);
7584 	      bfd_put_32 (output_bfd, cinfo.symindx, contents + 4);
7585 	      bfd_put_32 (output_bfd, maskwords, contents + 8);
7586 	      bfd_put_32 (output_bfd, cinfo.shift2, contents + 12);
7587 	      contents += 16 + cinfo.maskbits / 8;
7588 
7589 	      for (i = 0; i < bucketcount; ++i)
7590 		{
7591 		  if (cinfo.counts[i] == 0)
7592 		    bfd_put_32 (output_bfd, 0, contents);
7593 		  else
7594 		    bfd_put_32 (output_bfd, cinfo.indx[i], contents);
7595 		  contents += 4;
7596 		}
7597 
7598 	      cinfo.contents = contents;
7599 
7600 	      cinfo.xlat = contents + cinfo.nsyms * 4 - s->contents;
7601 	      /* Renumber dynamic symbols, if populating .gnu.hash section.
7602 		 If using .MIPS.xhash, populate the translation table.  */
7603 	      elf_link_hash_traverse (elf_hash_table (info),
7604 				      elf_gnu_hash_process_symidx, &cinfo);
7605 
7606 	      contents = s->contents + 16;
7607 	      for (i = 0; i < maskwords; ++i)
7608 		{
7609 		  bfd_put (bed->s->arch_size, output_bfd, cinfo.bitmask[i],
7610 			   contents);
7611 		  contents += bed->s->arch_size / 8;
7612 		}
7613 
7614 	      free (cinfo.bitmask);
7615 	      free (cinfo.hashcodes);
7616 	    }
7617 	}
7618 
7619       s = bfd_get_linker_section (dynobj, ".dynstr");
7620       BFD_ASSERT (s != NULL);
7621 
7622       elf_finalize_dynstr (output_bfd, info);
7623 
7624       s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
7625 
7626       for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
7627 	if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
7628 	  return false;
7629     }
7630 
7631   return true;
7632 }
7633 
7634 /* Make sure sec_info_type is cleared if sec_info is cleared too.  */
7635 
7636 static void
merge_sections_remove_hook(bfd * abfd ATTRIBUTE_UNUSED,asection * sec)7637 merge_sections_remove_hook (bfd *abfd ATTRIBUTE_UNUSED,
7638 			    asection *sec)
7639 {
7640   BFD_ASSERT (sec->sec_info_type == SEC_INFO_TYPE_MERGE);
7641   sec->sec_info_type = SEC_INFO_TYPE_NONE;
7642 }
7643 
7644 /* Finish SHF_MERGE section merging.  */
7645 
7646 bool
_bfd_elf_merge_sections(bfd * obfd,struct bfd_link_info * info)7647 _bfd_elf_merge_sections (bfd *obfd, struct bfd_link_info *info)
7648 {
7649   bfd *ibfd;
7650   asection *sec;
7651 
7652   if (!is_elf_hash_table (info->hash))
7653     return false;
7654 
7655   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
7656     if ((ibfd->flags & DYNAMIC) == 0
7657 	&& bfd_get_flavour (ibfd) == bfd_target_elf_flavour
7658 	&& (elf_elfheader (ibfd)->e_ident[EI_CLASS]
7659 	    == get_elf_backend_data (obfd)->s->elfclass))
7660       for (sec = ibfd->sections; sec != NULL; sec = sec->next)
7661 	if ((sec->flags & SEC_MERGE) != 0
7662 	    && !bfd_is_abs_section (sec->output_section))
7663 	  {
7664 	    struct bfd_elf_section_data *secdata;
7665 
7666 	    secdata = elf_section_data (sec);
7667 	    if (! _bfd_add_merge_section (obfd,
7668 					  &elf_hash_table (info)->merge_info,
7669 					  sec, &secdata->sec_info))
7670 	      return false;
7671 	    else if (secdata->sec_info)
7672 	      sec->sec_info_type = SEC_INFO_TYPE_MERGE;
7673 	  }
7674 
7675   if (elf_hash_table (info)->merge_info != NULL)
7676     _bfd_merge_sections (obfd, info, elf_hash_table (info)->merge_info,
7677 			 merge_sections_remove_hook);
7678   return true;
7679 }
7680 
7681 /* Create an entry in an ELF linker hash table.  */
7682 
7683 struct bfd_hash_entry *
_bfd_elf_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)7684 _bfd_elf_link_hash_newfunc (struct bfd_hash_entry *entry,
7685 			    struct bfd_hash_table *table,
7686 			    const char *string)
7687 {
7688   /* Allocate the structure if it has not already been allocated by a
7689      subclass.  */
7690   if (entry == NULL)
7691     {
7692       entry = (struct bfd_hash_entry *)
7693 	bfd_hash_allocate (table, sizeof (struct elf_link_hash_entry));
7694       if (entry == NULL)
7695 	return entry;
7696     }
7697 
7698   /* Call the allocation method of the superclass.  */
7699   entry = _bfd_link_hash_newfunc (entry, table, string);
7700   if (entry != NULL)
7701     {
7702       struct elf_link_hash_entry *ret = (struct elf_link_hash_entry *) entry;
7703       struct elf_link_hash_table *htab = (struct elf_link_hash_table *) table;
7704 
7705       /* Set local fields.  */
7706       ret->indx = -1;
7707       ret->dynindx = -1;
7708       ret->got = htab->init_got_refcount;
7709       ret->plt = htab->init_plt_refcount;
7710       memset (&ret->size, 0, (sizeof (struct elf_link_hash_entry)
7711 			      - offsetof (struct elf_link_hash_entry, size)));
7712       /* Assume that we have been called by a non-ELF symbol reader.
7713 	 This flag is then reset by the code which reads an ELF input
7714 	 file.  This ensures that a symbol created by a non-ELF symbol
7715 	 reader will have the flag set correctly.  */
7716       ret->non_elf = 1;
7717     }
7718 
7719   return entry;
7720 }
7721 
7722 /* Copy data from an indirect symbol to its direct symbol, hiding the
7723    old indirect symbol.  Also used for copying flags to a weakdef.  */
7724 
7725 void
_bfd_elf_link_hash_copy_indirect(struct bfd_link_info * info,struct elf_link_hash_entry * dir,struct elf_link_hash_entry * ind)7726 _bfd_elf_link_hash_copy_indirect (struct bfd_link_info *info,
7727 				  struct elf_link_hash_entry *dir,
7728 				  struct elf_link_hash_entry *ind)
7729 {
7730   struct elf_link_hash_table *htab;
7731 
7732   if (ind->dyn_relocs != NULL)
7733     {
7734       if (dir->dyn_relocs != NULL)
7735 	{
7736 	  struct elf_dyn_relocs **pp;
7737 	  struct elf_dyn_relocs *p;
7738 
7739 	  /* Add reloc counts against the indirect sym to the direct sym
7740 	     list.  Merge any entries against the same section.  */
7741 	  for (pp = &ind->dyn_relocs; (p = *pp) != NULL; )
7742 	    {
7743 	      struct elf_dyn_relocs *q;
7744 
7745 	      for (q = dir->dyn_relocs; q != NULL; q = q->next)
7746 		if (q->sec == p->sec)
7747 		  {
7748 		    q->pc_count += p->pc_count;
7749 		    q->count += p->count;
7750 		    *pp = p->next;
7751 		    break;
7752 		  }
7753 	      if (q == NULL)
7754 		pp = &p->next;
7755 	    }
7756 	  *pp = dir->dyn_relocs;
7757 	}
7758 
7759       dir->dyn_relocs = ind->dyn_relocs;
7760       ind->dyn_relocs = NULL;
7761     }
7762 
7763   /* Copy down any references that we may have already seen to the
7764      symbol which just became indirect.  */
7765 
7766   if (dir->versioned != versioned_hidden)
7767     dir->ref_dynamic |= ind->ref_dynamic;
7768   dir->ref_regular |= ind->ref_regular;
7769   dir->ref_regular_nonweak |= ind->ref_regular_nonweak;
7770   dir->non_got_ref |= ind->non_got_ref;
7771   dir->needs_plt |= ind->needs_plt;
7772   dir->pointer_equality_needed |= ind->pointer_equality_needed;
7773 
7774   if (ind->root.type != bfd_link_hash_indirect)
7775     return;
7776 
7777   /* Copy over the global and procedure linkage table refcount entries.
7778      These may have been already set up by a check_relocs routine.  */
7779   htab = elf_hash_table (info);
7780   if (ind->got.refcount > htab->init_got_refcount.refcount)
7781     {
7782       if (dir->got.refcount < 0)
7783 	dir->got.refcount = 0;
7784       dir->got.refcount += ind->got.refcount;
7785       ind->got.refcount = htab->init_got_refcount.refcount;
7786     }
7787 
7788   if (ind->plt.refcount > htab->init_plt_refcount.refcount)
7789     {
7790       if (dir->plt.refcount < 0)
7791 	dir->plt.refcount = 0;
7792       dir->plt.refcount += ind->plt.refcount;
7793       ind->plt.refcount = htab->init_plt_refcount.refcount;
7794     }
7795 
7796   if (ind->dynindx != -1)
7797     {
7798       if (dir->dynindx != -1)
7799 	_bfd_elf_strtab_delref (htab->dynstr, dir->dynstr_index);
7800       dir->dynindx = ind->dynindx;
7801       dir->dynstr_index = ind->dynstr_index;
7802       ind->dynindx = -1;
7803       ind->dynstr_index = 0;
7804     }
7805 }
7806 
7807 void
_bfd_elf_link_hash_hide_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h,bool force_local)7808 _bfd_elf_link_hash_hide_symbol (struct bfd_link_info *info,
7809 				struct elf_link_hash_entry *h,
7810 				bool force_local)
7811 {
7812   /* STT_GNU_IFUNC symbol must go through PLT.  */
7813   if (h->type != STT_GNU_IFUNC)
7814     {
7815       h->plt = elf_hash_table (info)->init_plt_offset;
7816       h->needs_plt = 0;
7817     }
7818   if (force_local)
7819     {
7820       h->forced_local = 1;
7821       if (h->dynindx != -1)
7822 	{
7823 	  _bfd_elf_strtab_delref (elf_hash_table (info)->dynstr,
7824 				  h->dynstr_index);
7825 	  h->dynindx = -1;
7826 	  h->dynstr_index = 0;
7827 	}
7828     }
7829 }
7830 
7831 /* Hide a symbol. */
7832 
7833 void
_bfd_elf_link_hide_symbol(bfd * output_bfd,struct bfd_link_info * info,struct bfd_link_hash_entry * h)7834 _bfd_elf_link_hide_symbol (bfd *output_bfd,
7835 			   struct bfd_link_info *info,
7836 			   struct bfd_link_hash_entry *h)
7837 {
7838   if (is_elf_hash_table (info->hash))
7839     {
7840       const struct elf_backend_data *bed
7841 	= get_elf_backend_data (output_bfd);
7842       struct elf_link_hash_entry *eh
7843 	= (struct elf_link_hash_entry *) h;
7844       bed->elf_backend_hide_symbol (info, eh, true);
7845       eh->def_dynamic = 0;
7846       eh->ref_dynamic = 0;
7847       eh->dynamic_def = 0;
7848     }
7849 }
7850 
7851 /* Initialize an ELF linker hash table.  *TABLE has been zeroed by our
7852    caller.  */
7853 
7854 bool
_bfd_elf_link_hash_table_init(struct elf_link_hash_table * table,bfd * abfd,struct bfd_hash_entry * (* newfunc)(struct bfd_hash_entry *,struct bfd_hash_table *,const char *),unsigned int entsize,enum elf_target_id target_id)7855 _bfd_elf_link_hash_table_init
7856   (struct elf_link_hash_table *table,
7857    bfd *abfd,
7858    struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
7859 				      struct bfd_hash_table *,
7860 				      const char *),
7861    unsigned int entsize,
7862    enum elf_target_id target_id)
7863 {
7864   bool ret;
7865   int can_refcount = get_elf_backend_data (abfd)->can_refcount;
7866 
7867   table->init_got_refcount.refcount = can_refcount - 1;
7868   table->init_plt_refcount.refcount = can_refcount - 1;
7869   table->init_got_offset.offset = -(bfd_vma) 1;
7870   table->init_plt_offset.offset = -(bfd_vma) 1;
7871   /* The first dynamic symbol is a dummy.  */
7872   table->dynsymcount = 1;
7873 
7874   ret = _bfd_link_hash_table_init (&table->root, abfd, newfunc, entsize);
7875 
7876   table->root.type = bfd_link_elf_hash_table;
7877   table->hash_table_id = target_id;
7878   table->target_os = get_elf_backend_data (abfd)->target_os;
7879 
7880   return ret;
7881 }
7882 
7883 /* Create an ELF linker hash table.  */
7884 
7885 struct bfd_link_hash_table *
_bfd_elf_link_hash_table_create(bfd * abfd)7886 _bfd_elf_link_hash_table_create (bfd *abfd)
7887 {
7888   struct elf_link_hash_table *ret;
7889   size_t amt = sizeof (struct elf_link_hash_table);
7890 
7891   ret = (struct elf_link_hash_table *) bfd_zmalloc (amt);
7892   if (ret == NULL)
7893     return NULL;
7894 
7895   if (! _bfd_elf_link_hash_table_init (ret, abfd, _bfd_elf_link_hash_newfunc,
7896 				       sizeof (struct elf_link_hash_entry),
7897 				       GENERIC_ELF_DATA))
7898     {
7899       free (ret);
7900       return NULL;
7901     }
7902   ret->root.hash_table_free = _bfd_elf_link_hash_table_free;
7903 
7904   return &ret->root;
7905 }
7906 
7907 /* Destroy an ELF linker hash table.  */
7908 
7909 void
_bfd_elf_link_hash_table_free(bfd * obfd)7910 _bfd_elf_link_hash_table_free (bfd *obfd)
7911 {
7912   struct elf_link_hash_table *htab;
7913 
7914   htab = (struct elf_link_hash_table *) obfd->link.hash;
7915   if (htab->dynstr != NULL)
7916     _bfd_elf_strtab_free (htab->dynstr);
7917   _bfd_merge_sections_free (htab->merge_info);
7918   _bfd_generic_link_hash_table_free (obfd);
7919 }
7920 
7921 /* This is a hook for the ELF emulation code in the generic linker to
7922    tell the backend linker what file name to use for the DT_NEEDED
7923    entry for a dynamic object.  */
7924 
7925 void
bfd_elf_set_dt_needed_name(bfd * abfd,const char * name)7926 bfd_elf_set_dt_needed_name (bfd *abfd, const char *name)
7927 {
7928   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
7929       && bfd_get_format (abfd) == bfd_object)
7930     elf_dt_name (abfd) = name;
7931 }
7932 
7933 int
bfd_elf_get_dyn_lib_class(bfd * abfd)7934 bfd_elf_get_dyn_lib_class (bfd *abfd)
7935 {
7936   int lib_class;
7937   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
7938       && bfd_get_format (abfd) == bfd_object)
7939     lib_class = elf_dyn_lib_class (abfd);
7940   else
7941     lib_class = 0;
7942   return lib_class;
7943 }
7944 
7945 void
bfd_elf_set_dyn_lib_class(bfd * abfd,enum dynamic_lib_link_class lib_class)7946 bfd_elf_set_dyn_lib_class (bfd *abfd, enum dynamic_lib_link_class lib_class)
7947 {
7948   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
7949       && bfd_get_format (abfd) == bfd_object)
7950     elf_dyn_lib_class (abfd) = lib_class;
7951 }
7952 
7953 /* Get the list of DT_NEEDED entries for a link.  This is a hook for
7954    the linker ELF emulation code.  */
7955 
7956 struct bfd_link_needed_list *
bfd_elf_get_needed_list(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)7957 bfd_elf_get_needed_list (bfd *abfd ATTRIBUTE_UNUSED,
7958 			 struct bfd_link_info *info)
7959 {
7960   if (! is_elf_hash_table (info->hash))
7961     return NULL;
7962   return elf_hash_table (info)->needed;
7963 }
7964 
7965 /* Get the list of DT_RPATH/DT_RUNPATH entries for a link.  This is a
7966    hook for the linker ELF emulation code.  */
7967 
7968 struct bfd_link_needed_list *
bfd_elf_get_runpath_list(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)7969 bfd_elf_get_runpath_list (bfd *abfd ATTRIBUTE_UNUSED,
7970 			  struct bfd_link_info *info)
7971 {
7972   if (! is_elf_hash_table (info->hash))
7973     return NULL;
7974   return elf_hash_table (info)->runpath;
7975 }
7976 
7977 /* Get the name actually used for a dynamic object for a link.  This
7978    is the SONAME entry if there is one.  Otherwise, it is the string
7979    passed to bfd_elf_set_dt_needed_name, or it is the filename.  */
7980 
7981 const char *
bfd_elf_get_dt_soname(bfd * abfd)7982 bfd_elf_get_dt_soname (bfd *abfd)
7983 {
7984   if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
7985       && bfd_get_format (abfd) == bfd_object)
7986     return elf_dt_name (abfd);
7987   return NULL;
7988 }
7989 
7990 /* Get the list of DT_NEEDED entries from a BFD.  This is a hook for
7991    the ELF linker emulation code.  */
7992 
7993 bool
bfd_elf_get_bfd_needed_list(bfd * abfd,struct bfd_link_needed_list ** pneeded)7994 bfd_elf_get_bfd_needed_list (bfd *abfd,
7995 			     struct bfd_link_needed_list **pneeded)
7996 {
7997   asection *s;
7998   bfd_byte *dynbuf = NULL;
7999   unsigned int elfsec;
8000   unsigned long shlink;
8001   bfd_byte *extdyn, *extdynend;
8002   size_t extdynsize;
8003   void (*swap_dyn_in) (bfd *, const void *, Elf_Internal_Dyn *);
8004 
8005   *pneeded = NULL;
8006 
8007   if (bfd_get_flavour (abfd) != bfd_target_elf_flavour
8008       || bfd_get_format (abfd) != bfd_object)
8009     return true;
8010 
8011   s = bfd_get_section_by_name (abfd, ".dynamic");
8012   if (s == NULL || s->size == 0)
8013     return true;
8014 
8015   if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
8016     goto error_return;
8017 
8018   elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
8019   if (elfsec == SHN_BAD)
8020     goto error_return;
8021 
8022   shlink = elf_elfsections (abfd)[elfsec]->sh_link;
8023 
8024   extdynsize = get_elf_backend_data (abfd)->s->sizeof_dyn;
8025   swap_dyn_in = get_elf_backend_data (abfd)->s->swap_dyn_in;
8026 
8027   extdyn = dynbuf;
8028   extdynend = extdyn + s->size;
8029   for (; extdyn < extdynend; extdyn += extdynsize)
8030     {
8031       Elf_Internal_Dyn dyn;
8032 
8033       (*swap_dyn_in) (abfd, extdyn, &dyn);
8034 
8035       if (dyn.d_tag == DT_NULL)
8036 	break;
8037 
8038       if (dyn.d_tag == DT_NEEDED)
8039 	{
8040 	  const char *string;
8041 	  struct bfd_link_needed_list *l;
8042 	  unsigned int tagv = dyn.d_un.d_val;
8043 	  size_t amt;
8044 
8045 	  string = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
8046 	  if (string == NULL)
8047 	    goto error_return;
8048 
8049 	  amt = sizeof *l;
8050 	  l = (struct bfd_link_needed_list *) bfd_alloc (abfd, amt);
8051 	  if (l == NULL)
8052 	    goto error_return;
8053 
8054 	  l->by = abfd;
8055 	  l->name = string;
8056 	  l->next = *pneeded;
8057 	  *pneeded = l;
8058 	}
8059     }
8060 
8061   free (dynbuf);
8062 
8063   return true;
8064 
8065  error_return:
8066   free (dynbuf);
8067   return false;
8068 }
8069 
8070 struct elf_symbuf_symbol
8071 {
8072   unsigned long st_name;	/* Symbol name, index in string tbl */
8073   unsigned char st_info;	/* Type and binding attributes */
8074   unsigned char st_other;	/* Visibilty, and target specific */
8075 };
8076 
8077 struct elf_symbuf_head
8078 {
8079   struct elf_symbuf_symbol *ssym;
8080   size_t count;
8081   unsigned int st_shndx;
8082 };
8083 
8084 struct elf_symbol
8085 {
8086   union
8087     {
8088       Elf_Internal_Sym *isym;
8089       struct elf_symbuf_symbol *ssym;
8090       void *p;
8091     } u;
8092   const char *name;
8093 };
8094 
8095 /* Sort references to symbols by ascending section number.  */
8096 
8097 static int
elf_sort_elf_symbol(const void * arg1,const void * arg2)8098 elf_sort_elf_symbol (const void *arg1, const void *arg2)
8099 {
8100   const Elf_Internal_Sym *s1 = *(const Elf_Internal_Sym **) arg1;
8101   const Elf_Internal_Sym *s2 = *(const Elf_Internal_Sym **) arg2;
8102 
8103   if (s1->st_shndx != s2->st_shndx)
8104     return s1->st_shndx > s2->st_shndx ? 1 : -1;
8105   /* Final sort by the address of the sym in the symbuf ensures
8106      a stable sort.  */
8107   if (s1 != s2)
8108     return s1 > s2 ? 1 : -1;
8109   return 0;
8110 }
8111 
8112 static int
elf_sym_name_compare(const void * arg1,const void * arg2)8113 elf_sym_name_compare (const void *arg1, const void *arg2)
8114 {
8115   const struct elf_symbol *s1 = (const struct elf_symbol *) arg1;
8116   const struct elf_symbol *s2 = (const struct elf_symbol *) arg2;
8117   int ret = strcmp (s1->name, s2->name);
8118   if (ret != 0)
8119     return ret;
8120   if (s1->u.p != s2->u.p)
8121     return s1->u.p > s2->u.p ? 1 : -1;
8122   return 0;
8123 }
8124 
8125 static struct elf_symbuf_head *
elf_create_symbuf(size_t symcount,Elf_Internal_Sym * isymbuf)8126 elf_create_symbuf (size_t symcount, Elf_Internal_Sym *isymbuf)
8127 {
8128   Elf_Internal_Sym **ind, **indbufend, **indbuf;
8129   struct elf_symbuf_symbol *ssym;
8130   struct elf_symbuf_head *ssymbuf, *ssymhead;
8131   size_t i, shndx_count, total_size, amt;
8132 
8133   amt = symcount * sizeof (*indbuf);
8134   indbuf = (Elf_Internal_Sym **) bfd_malloc (amt);
8135   if (indbuf == NULL)
8136     return NULL;
8137 
8138   for (ind = indbuf, i = 0; i < symcount; i++)
8139     if (isymbuf[i].st_shndx != SHN_UNDEF)
8140       *ind++ = &isymbuf[i];
8141   indbufend = ind;
8142 
8143   qsort (indbuf, indbufend - indbuf, sizeof (Elf_Internal_Sym *),
8144 	 elf_sort_elf_symbol);
8145 
8146   shndx_count = 0;
8147   if (indbufend > indbuf)
8148     for (ind = indbuf, shndx_count++; ind < indbufend - 1; ind++)
8149       if (ind[0]->st_shndx != ind[1]->st_shndx)
8150 	shndx_count++;
8151 
8152   total_size = ((shndx_count + 1) * sizeof (*ssymbuf)
8153 		+ (indbufend - indbuf) * sizeof (*ssym));
8154   ssymbuf = (struct elf_symbuf_head *) bfd_malloc (total_size);
8155   if (ssymbuf == NULL)
8156     {
8157       free (indbuf);
8158       return NULL;
8159     }
8160 
8161   ssym = (struct elf_symbuf_symbol *) (ssymbuf + shndx_count + 1);
8162   ssymbuf->ssym = NULL;
8163   ssymbuf->count = shndx_count;
8164   ssymbuf->st_shndx = 0;
8165   for (ssymhead = ssymbuf, ind = indbuf; ind < indbufend; ssym++, ind++)
8166     {
8167       if (ind == indbuf || ssymhead->st_shndx != (*ind)->st_shndx)
8168 	{
8169 	  ssymhead++;
8170 	  ssymhead->ssym = ssym;
8171 	  ssymhead->count = 0;
8172 	  ssymhead->st_shndx = (*ind)->st_shndx;
8173 	}
8174       ssym->st_name = (*ind)->st_name;
8175       ssym->st_info = (*ind)->st_info;
8176       ssym->st_other = (*ind)->st_other;
8177       ssymhead->count++;
8178     }
8179   BFD_ASSERT ((size_t) (ssymhead - ssymbuf) == shndx_count
8180 	      && (((bfd_hostptr_t) ssym - (bfd_hostptr_t) ssymbuf)
8181 		  == total_size));
8182 
8183   free (indbuf);
8184   return ssymbuf;
8185 }
8186 
8187 /* Check if 2 sections define the same set of local and global
8188    symbols.  */
8189 
8190 static bool
bfd_elf_match_symbols_in_sections(asection * sec1,asection * sec2,struct bfd_link_info * info)8191 bfd_elf_match_symbols_in_sections (asection *sec1, asection *sec2,
8192 				   struct bfd_link_info *info)
8193 {
8194   bfd *bfd1, *bfd2;
8195   const struct elf_backend_data *bed1, *bed2;
8196   Elf_Internal_Shdr *hdr1, *hdr2;
8197   size_t symcount1, symcount2;
8198   Elf_Internal_Sym *isymbuf1, *isymbuf2;
8199   struct elf_symbuf_head *ssymbuf1, *ssymbuf2;
8200   Elf_Internal_Sym *isym, *isymend;
8201   struct elf_symbol *symtable1 = NULL, *symtable2 = NULL;
8202   size_t count1, count2, sec_count1, sec_count2, i;
8203   unsigned int shndx1, shndx2;
8204   bool result;
8205   bool ignore_section_symbol_p;
8206 
8207   bfd1 = sec1->owner;
8208   bfd2 = sec2->owner;
8209 
8210   /* Both sections have to be in ELF.  */
8211   if (bfd_get_flavour (bfd1) != bfd_target_elf_flavour
8212       || bfd_get_flavour (bfd2) != bfd_target_elf_flavour)
8213     return false;
8214 
8215   if (elf_section_type (sec1) != elf_section_type (sec2))
8216     return false;
8217 
8218   shndx1 = _bfd_elf_section_from_bfd_section (bfd1, sec1);
8219   shndx2 = _bfd_elf_section_from_bfd_section (bfd2, sec2);
8220   if (shndx1 == SHN_BAD || shndx2 == SHN_BAD)
8221     return false;
8222 
8223   bed1 = get_elf_backend_data (bfd1);
8224   bed2 = get_elf_backend_data (bfd2);
8225   hdr1 = &elf_tdata (bfd1)->symtab_hdr;
8226   symcount1 = hdr1->sh_size / bed1->s->sizeof_sym;
8227   hdr2 = &elf_tdata (bfd2)->symtab_hdr;
8228   symcount2 = hdr2->sh_size / bed2->s->sizeof_sym;
8229 
8230   if (symcount1 == 0 || symcount2 == 0)
8231     return false;
8232 
8233   result = false;
8234   isymbuf1 = NULL;
8235   isymbuf2 = NULL;
8236   ssymbuf1 = (struct elf_symbuf_head *) elf_tdata (bfd1)->symbuf;
8237   ssymbuf2 = (struct elf_symbuf_head *) elf_tdata (bfd2)->symbuf;
8238 
8239   /* Ignore section symbols only when matching non-debugging sections
8240      or linkonce section with comdat section.  */
8241   ignore_section_symbol_p
8242     = ((sec1->flags & SEC_DEBUGGING) == 0
8243        || ((elf_section_flags (sec1) & SHF_GROUP)
8244 	   != (elf_section_flags (sec2) & SHF_GROUP)));
8245 
8246   if (ssymbuf1 == NULL)
8247     {
8248       isymbuf1 = bfd_elf_get_elf_syms (bfd1, hdr1, symcount1, 0,
8249 				       NULL, NULL, NULL);
8250       if (isymbuf1 == NULL)
8251 	goto done;
8252 
8253       if (info != NULL && !info->reduce_memory_overheads)
8254 	{
8255 	  ssymbuf1 = elf_create_symbuf (symcount1, isymbuf1);
8256 	  elf_tdata (bfd1)->symbuf = ssymbuf1;
8257 	}
8258     }
8259 
8260   if (ssymbuf1 == NULL || ssymbuf2 == NULL)
8261     {
8262       isymbuf2 = bfd_elf_get_elf_syms (bfd2, hdr2, symcount2, 0,
8263 				       NULL, NULL, NULL);
8264       if (isymbuf2 == NULL)
8265 	goto done;
8266 
8267       if (ssymbuf1 != NULL && info != NULL && !info->reduce_memory_overheads)
8268 	{
8269 	  ssymbuf2 = elf_create_symbuf (symcount2, isymbuf2);
8270 	  elf_tdata (bfd2)->symbuf = ssymbuf2;
8271 	}
8272     }
8273 
8274   if (ssymbuf1 != NULL && ssymbuf2 != NULL)
8275     {
8276       /* Optimized faster version.  */
8277       size_t lo, hi, mid;
8278       struct elf_symbol *symp;
8279       struct elf_symbuf_symbol *ssym, *ssymend;
8280 
8281       lo = 0;
8282       hi = ssymbuf1->count;
8283       ssymbuf1++;
8284       count1 = 0;
8285       sec_count1 = 0;
8286       while (lo < hi)
8287 	{
8288 	  mid = (lo + hi) / 2;
8289 	  if (shndx1 < ssymbuf1[mid].st_shndx)
8290 	    hi = mid;
8291 	  else if (shndx1 > ssymbuf1[mid].st_shndx)
8292 	    lo = mid + 1;
8293 	  else
8294 	    {
8295 	      count1 = ssymbuf1[mid].count;
8296 	      ssymbuf1 += mid;
8297 	      break;
8298 	    }
8299 	}
8300       if (ignore_section_symbol_p)
8301 	{
8302 	  for (i = 0; i < count1; i++)
8303 	    if (ELF_ST_TYPE (ssymbuf1->ssym[i].st_info) == STT_SECTION)
8304 	      sec_count1++;
8305 	  count1 -= sec_count1;
8306 	}
8307 
8308       lo = 0;
8309       hi = ssymbuf2->count;
8310       ssymbuf2++;
8311       count2 = 0;
8312       sec_count2 = 0;
8313       while (lo < hi)
8314 	{
8315 	  mid = (lo + hi) / 2;
8316 	  if (shndx2 < ssymbuf2[mid].st_shndx)
8317 	    hi = mid;
8318 	  else if (shndx2 > ssymbuf2[mid].st_shndx)
8319 	    lo = mid + 1;
8320 	  else
8321 	    {
8322 	      count2 = ssymbuf2[mid].count;
8323 	      ssymbuf2 += mid;
8324 	      break;
8325 	    }
8326 	}
8327       if (ignore_section_symbol_p)
8328 	{
8329 	  for (i = 0; i < count2; i++)
8330 	    if (ELF_ST_TYPE (ssymbuf2->ssym[i].st_info) == STT_SECTION)
8331 	      sec_count2++;
8332 	  count2 -= sec_count2;
8333 	}
8334 
8335       if (count1 == 0 || count2 == 0 || count1 != count2)
8336 	goto done;
8337 
8338       symtable1
8339 	= (struct elf_symbol *) bfd_malloc (count1 * sizeof (*symtable1));
8340       symtable2
8341 	= (struct elf_symbol *) bfd_malloc (count2 * sizeof (*symtable2));
8342       if (symtable1 == NULL || symtable2 == NULL)
8343 	goto done;
8344 
8345       symp = symtable1;
8346       for (ssym = ssymbuf1->ssym, ssymend = ssym + count1 + sec_count1;
8347 	   ssym < ssymend; ssym++)
8348 	if (sec_count1 == 0
8349 	    || ELF_ST_TYPE (ssym->st_info) != STT_SECTION)
8350 	  {
8351 	    symp->u.ssym = ssym;
8352 	    symp->name = bfd_elf_string_from_elf_section (bfd1,
8353 							  hdr1->sh_link,
8354 							  ssym->st_name);
8355 	    symp++;
8356 	  }
8357 
8358       symp = symtable2;
8359       for (ssym = ssymbuf2->ssym, ssymend = ssym + count2 + sec_count2;
8360 	   ssym < ssymend; ssym++)
8361 	if (sec_count2 == 0
8362 	    || ELF_ST_TYPE (ssym->st_info) != STT_SECTION)
8363 	  {
8364 	    symp->u.ssym = ssym;
8365 	    symp->name = bfd_elf_string_from_elf_section (bfd2,
8366 							  hdr2->sh_link,
8367 							  ssym->st_name);
8368 	    symp++;
8369 	  }
8370 
8371       /* Sort symbol by name.  */
8372       qsort (symtable1, count1, sizeof (struct elf_symbol),
8373 	     elf_sym_name_compare);
8374       qsort (symtable2, count1, sizeof (struct elf_symbol),
8375 	     elf_sym_name_compare);
8376 
8377       for (i = 0; i < count1; i++)
8378 	/* Two symbols must have the same binding, type and name.  */
8379 	if (symtable1 [i].u.ssym->st_info != symtable2 [i].u.ssym->st_info
8380 	    || symtable1 [i].u.ssym->st_other != symtable2 [i].u.ssym->st_other
8381 	    || strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
8382 	  goto done;
8383 
8384       result = true;
8385       goto done;
8386     }
8387 
8388   symtable1 = (struct elf_symbol *)
8389       bfd_malloc (symcount1 * sizeof (struct elf_symbol));
8390   symtable2 = (struct elf_symbol *)
8391       bfd_malloc (symcount2 * sizeof (struct elf_symbol));
8392   if (symtable1 == NULL || symtable2 == NULL)
8393     goto done;
8394 
8395   /* Count definitions in the section.  */
8396   count1 = 0;
8397   for (isym = isymbuf1, isymend = isym + symcount1; isym < isymend; isym++)
8398     if (isym->st_shndx == shndx1
8399 	&& (!ignore_section_symbol_p
8400 	    || ELF_ST_TYPE (isym->st_info) != STT_SECTION))
8401       symtable1[count1++].u.isym = isym;
8402 
8403   count2 = 0;
8404   for (isym = isymbuf2, isymend = isym + symcount2; isym < isymend; isym++)
8405     if (isym->st_shndx == shndx2
8406 	&& (!ignore_section_symbol_p
8407 	    || ELF_ST_TYPE (isym->st_info) != STT_SECTION))
8408       symtable2[count2++].u.isym = isym;
8409 
8410   if (count1 == 0 || count2 == 0 || count1 != count2)
8411     goto done;
8412 
8413   for (i = 0; i < count1; i++)
8414     symtable1[i].name
8415       = bfd_elf_string_from_elf_section (bfd1, hdr1->sh_link,
8416 					 symtable1[i].u.isym->st_name);
8417 
8418   for (i = 0; i < count2; i++)
8419     symtable2[i].name
8420       = bfd_elf_string_from_elf_section (bfd2, hdr2->sh_link,
8421 					 symtable2[i].u.isym->st_name);
8422 
8423   /* Sort symbol by name.  */
8424   qsort (symtable1, count1, sizeof (struct elf_symbol),
8425 	 elf_sym_name_compare);
8426   qsort (symtable2, count1, sizeof (struct elf_symbol),
8427 	 elf_sym_name_compare);
8428 
8429   for (i = 0; i < count1; i++)
8430     /* Two symbols must have the same binding, type and name.  */
8431     if (symtable1 [i].u.isym->st_info != symtable2 [i].u.isym->st_info
8432 	|| symtable1 [i].u.isym->st_other != symtable2 [i].u.isym->st_other
8433 	|| strcmp (symtable1 [i].name, symtable2 [i].name) != 0)
8434       goto done;
8435 
8436   result = true;
8437 
8438  done:
8439   free (symtable1);
8440   free (symtable2);
8441   free (isymbuf1);
8442   free (isymbuf2);
8443 
8444   return result;
8445 }
8446 
8447 /* Return TRUE if 2 section types are compatible.  */
8448 
8449 bool
_bfd_elf_match_sections_by_type(bfd * abfd,const asection * asec,bfd * bbfd,const asection * bsec)8450 _bfd_elf_match_sections_by_type (bfd *abfd, const asection *asec,
8451 				 bfd *bbfd, const asection *bsec)
8452 {
8453   if (asec == NULL
8454       || bsec == NULL
8455       || abfd->xvec->flavour != bfd_target_elf_flavour
8456       || bbfd->xvec->flavour != bfd_target_elf_flavour)
8457     return true;
8458 
8459   return elf_section_type (asec) == elf_section_type (bsec);
8460 }
8461 
8462 /* Final phase of ELF linker.  */
8463 
8464 /* A structure we use to avoid passing large numbers of arguments.  */
8465 
8466 struct elf_final_link_info
8467 {
8468   /* General link information.  */
8469   struct bfd_link_info *info;
8470   /* Output BFD.  */
8471   bfd *output_bfd;
8472   /* Symbol string table.  */
8473   struct elf_strtab_hash *symstrtab;
8474   /* .hash section.  */
8475   asection *hash_sec;
8476   /* symbol version section (.gnu.version).  */
8477   asection *symver_sec;
8478   /* Buffer large enough to hold contents of any section.  */
8479   bfd_byte *contents;
8480   /* Buffer large enough to hold external relocs of any section.  */
8481   void *external_relocs;
8482   /* Buffer large enough to hold internal relocs of any section.  */
8483   Elf_Internal_Rela *internal_relocs;
8484   /* Buffer large enough to hold external local symbols of any input
8485      BFD.  */
8486   bfd_byte *external_syms;
8487   /* And a buffer for symbol section indices.  */
8488   Elf_External_Sym_Shndx *locsym_shndx;
8489   /* Buffer large enough to hold internal local symbols of any input
8490      BFD.  */
8491   Elf_Internal_Sym *internal_syms;
8492   /* Array large enough to hold a symbol index for each local symbol
8493      of any input BFD.  */
8494   long *indices;
8495   /* Array large enough to hold a section pointer for each local
8496      symbol of any input BFD.  */
8497   asection **sections;
8498   /* Buffer for SHT_SYMTAB_SHNDX section.  */
8499   Elf_External_Sym_Shndx *symshndxbuf;
8500   /* Number of STT_FILE syms seen.  */
8501   size_t filesym_count;
8502   /* Local symbol hash table.  */
8503   struct bfd_hash_table local_hash_table;
8504 };
8505 
8506 struct local_hash_entry
8507 {
8508   /* Base hash table entry structure.  */
8509   struct bfd_hash_entry root;
8510   /* Size of the local symbol name.  */
8511   size_t size;
8512   /* Number of the duplicated local symbol names.  */
8513   long count;
8514 };
8515 
8516 /* Create an entry in the local symbol hash table.  */
8517 
8518 static struct bfd_hash_entry *
local_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)8519 local_hash_newfunc (struct bfd_hash_entry *entry,
8520 		    struct bfd_hash_table *table,
8521 		    const char *string)
8522 {
8523 
8524   /* Allocate the structure if it has not already been allocated by a
8525      subclass.  */
8526   if (entry == NULL)
8527     {
8528       entry = bfd_hash_allocate (table,
8529 				 sizeof (struct local_hash_entry));
8530       if (entry == NULL)
8531         return entry;
8532     }
8533 
8534   /* Call the allocation method of the superclass.  */
8535   entry = bfd_hash_newfunc (entry, table, string);
8536   if (entry != NULL)
8537     {
8538       ((struct local_hash_entry *) entry)->count = 0;
8539       ((struct local_hash_entry *) entry)->size = 0;
8540     }
8541 
8542   return entry;
8543 }
8544 
8545 /* This struct is used to pass information to elf_link_output_extsym.  */
8546 
8547 struct elf_outext_info
8548 {
8549   bool failed;
8550   bool localsyms;
8551   bool file_sym_done;
8552   struct elf_final_link_info *flinfo;
8553 };
8554 
8555 
8556 /* Support for evaluating a complex relocation.
8557 
8558    Complex relocations are generalized, self-describing relocations.  The
8559    implementation of them consists of two parts: complex symbols, and the
8560    relocations themselves.
8561 
8562    The relocations use a reserved elf-wide relocation type code (R_RELC
8563    external / BFD_RELOC_RELC internal) and an encoding of relocation field
8564    information (start bit, end bit, word width, etc) into the addend.  This
8565    information is extracted from CGEN-generated operand tables within gas.
8566 
8567    Complex symbols are mangled symbols (STT_RELC external / BSF_RELC
8568    internal) representing prefix-notation expressions, including but not
8569    limited to those sorts of expressions normally encoded as addends in the
8570    addend field.  The symbol mangling format is:
8571 
8572    <node> := <literal>
8573 	  |  <unary-operator> ':' <node>
8574 	  |  <binary-operator> ':' <node> ':' <node>
8575 	  ;
8576 
8577    <literal> := 's' <digits=N> ':' <N character symbol name>
8578 	     |  'S' <digits=N> ':' <N character section name>
8579 	     |  '#' <hexdigits>
8580 	     ;
8581 
8582    <binary-operator> := as in C
8583    <unary-operator> := as in C, plus "0-" for unambiguous negation.  */
8584 
8585 static void
set_symbol_value(bfd * bfd_with_globals,Elf_Internal_Sym * isymbuf,size_t locsymcount,size_t symidx,bfd_vma val)8586 set_symbol_value (bfd *bfd_with_globals,
8587 		  Elf_Internal_Sym *isymbuf,
8588 		  size_t locsymcount,
8589 		  size_t symidx,
8590 		  bfd_vma val)
8591 {
8592   struct elf_link_hash_entry **sym_hashes;
8593   struct elf_link_hash_entry *h;
8594   size_t extsymoff = locsymcount;
8595 
8596   if (symidx < locsymcount)
8597     {
8598       Elf_Internal_Sym *sym;
8599 
8600       sym = isymbuf + symidx;
8601       if (ELF_ST_BIND (sym->st_info) == STB_LOCAL)
8602 	{
8603 	  /* It is a local symbol: move it to the
8604 	     "absolute" section and give it a value.  */
8605 	  sym->st_shndx = SHN_ABS;
8606 	  sym->st_value = val;
8607 	  return;
8608 	}
8609       BFD_ASSERT (elf_bad_symtab (bfd_with_globals));
8610       extsymoff = 0;
8611     }
8612 
8613   /* It is a global symbol: set its link type
8614      to "defined" and give it a value.  */
8615 
8616   sym_hashes = elf_sym_hashes (bfd_with_globals);
8617   h = sym_hashes [symidx - extsymoff];
8618   while (h->root.type == bfd_link_hash_indirect
8619 	 || h->root.type == bfd_link_hash_warning)
8620     h = (struct elf_link_hash_entry *) h->root.u.i.link;
8621   h->root.type = bfd_link_hash_defined;
8622   h->root.u.def.value = val;
8623   h->root.u.def.section = bfd_abs_section_ptr;
8624 }
8625 
8626 static bool
resolve_symbol(const char * name,bfd * input_bfd,struct elf_final_link_info * flinfo,bfd_vma * result,Elf_Internal_Sym * isymbuf,size_t locsymcount)8627 resolve_symbol (const char *name,
8628 		bfd *input_bfd,
8629 		struct elf_final_link_info *flinfo,
8630 		bfd_vma *result,
8631 		Elf_Internal_Sym *isymbuf,
8632 		size_t locsymcount)
8633 {
8634   Elf_Internal_Sym *sym;
8635   struct bfd_link_hash_entry *global_entry;
8636   const char *candidate = NULL;
8637   Elf_Internal_Shdr *symtab_hdr;
8638   size_t i;
8639 
8640   symtab_hdr = & elf_tdata (input_bfd)->symtab_hdr;
8641 
8642   for (i = 0; i < locsymcount; ++ i)
8643     {
8644       sym = isymbuf + i;
8645 
8646       if (ELF_ST_BIND (sym->st_info) != STB_LOCAL)
8647 	continue;
8648 
8649       candidate = bfd_elf_string_from_elf_section (input_bfd,
8650 						   symtab_hdr->sh_link,
8651 						   sym->st_name);
8652 #ifdef DEBUG
8653       printf ("Comparing string: '%s' vs. '%s' = 0x%lx\n",
8654 	      name, candidate, (unsigned long) sym->st_value);
8655 #endif
8656       if (candidate && strcmp (candidate, name) == 0)
8657 	{
8658 	  asection *sec = flinfo->sections [i];
8659 
8660 	  *result = _bfd_elf_rel_local_sym (input_bfd, sym, &sec, 0);
8661 	  *result += sec->output_offset + sec->output_section->vma;
8662 #ifdef DEBUG
8663 	  printf ("Found symbol with value %8.8lx\n",
8664 		  (unsigned long) *result);
8665 #endif
8666 	  return true;
8667 	}
8668     }
8669 
8670   /* Hmm, haven't found it yet. perhaps it is a global.  */
8671   global_entry = bfd_link_hash_lookup (flinfo->info->hash, name,
8672 				       false, false, true);
8673   if (!global_entry)
8674     return false;
8675 
8676   if (global_entry->type == bfd_link_hash_defined
8677       || global_entry->type == bfd_link_hash_defweak)
8678     {
8679       *result = (global_entry->u.def.value
8680 		 + global_entry->u.def.section->output_section->vma
8681 		 + global_entry->u.def.section->output_offset);
8682 #ifdef DEBUG
8683       printf ("Found GLOBAL symbol '%s' with value %8.8lx\n",
8684 	      global_entry->root.string, (unsigned long) *result);
8685 #endif
8686       return true;
8687     }
8688 
8689   return false;
8690 }
8691 
8692 /* Looks up NAME in SECTIONS.  If found sets RESULT to NAME's address (in
8693    bytes) and returns TRUE, otherwise returns FALSE.  Accepts pseudo-section
8694    names like "foo.end" which is the end address of section "foo".  */
8695 
8696 static bool
resolve_section(const char * name,asection * sections,bfd_vma * result,bfd * abfd)8697 resolve_section (const char *name,
8698 		 asection *sections,
8699 		 bfd_vma *result,
8700 		 bfd * abfd)
8701 {
8702   asection *curr;
8703   unsigned int len;
8704 
8705   for (curr = sections; curr; curr = curr->next)
8706     if (strcmp (curr->name, name) == 0)
8707       {
8708 	*result = curr->vma;
8709 	return true;
8710       }
8711 
8712   /* Hmm. still haven't found it. try pseudo-section names.  */
8713   /* FIXME: This could be coded more efficiently...  */
8714   for (curr = sections; curr; curr = curr->next)
8715     {
8716       len = strlen (curr->name);
8717       if (len > strlen (name))
8718 	continue;
8719 
8720       if (strncmp (curr->name, name, len) == 0)
8721 	{
8722 	  if (startswith (name + len, ".end"))
8723 	    {
8724 	      *result = (curr->vma
8725 			 + curr->size / bfd_octets_per_byte (abfd, curr));
8726 	      return true;
8727 	    }
8728 
8729 	  /* Insert more pseudo-section names here, if you like.  */
8730 	}
8731     }
8732 
8733   return false;
8734 }
8735 
8736 static void
undefined_reference(const char * reftype,const char * name)8737 undefined_reference (const char *reftype, const char *name)
8738 {
8739   /* xgettext:c-format */
8740   _bfd_error_handler (_("undefined %s reference in complex symbol: %s"),
8741 		      reftype, name);
8742   bfd_set_error (bfd_error_bad_value);
8743 }
8744 
8745 static bool
eval_symbol(bfd_vma * result,const char ** symp,bfd * input_bfd,struct elf_final_link_info * flinfo,bfd_vma dot,Elf_Internal_Sym * isymbuf,size_t locsymcount,int signed_p)8746 eval_symbol (bfd_vma *result,
8747 	     const char **symp,
8748 	     bfd *input_bfd,
8749 	     struct elf_final_link_info *flinfo,
8750 	     bfd_vma dot,
8751 	     Elf_Internal_Sym *isymbuf,
8752 	     size_t locsymcount,
8753 	     int signed_p)
8754 {
8755   size_t len;
8756   size_t symlen;
8757   bfd_vma a;
8758   bfd_vma b;
8759   char symbuf[4096];
8760   const char *sym = *symp;
8761   const char *symend;
8762   bool symbol_is_section = false;
8763 
8764   len = strlen (sym);
8765   symend = sym + len;
8766 
8767   if (len < 1 || len > sizeof (symbuf))
8768     {
8769       bfd_set_error (bfd_error_invalid_operation);
8770       return false;
8771     }
8772 
8773   switch (* sym)
8774     {
8775     case '.':
8776       *result = dot;
8777       *symp = sym + 1;
8778       return true;
8779 
8780     case '#':
8781       ++sym;
8782       *result = strtoul (sym, (char **) symp, 16);
8783       return true;
8784 
8785     case 'S':
8786       symbol_is_section = true;
8787       /* Fall through.  */
8788     case 's':
8789       ++sym;
8790       symlen = strtol (sym, (char **) symp, 10);
8791       sym = *symp + 1; /* Skip the trailing ':'.  */
8792 
8793       if (symend < sym || symlen + 1 > sizeof (symbuf))
8794 	{
8795 	  bfd_set_error (bfd_error_invalid_operation);
8796 	  return false;
8797 	}
8798 
8799       memcpy (symbuf, sym, symlen);
8800       symbuf[symlen] = '\0';
8801       *symp = sym + symlen;
8802 
8803       /* Is it always possible, with complex symbols, that gas "mis-guessed"
8804 	 the symbol as a section, or vice-versa. so we're pretty liberal in our
8805 	 interpretation here; section means "try section first", not "must be a
8806 	 section", and likewise with symbol.  */
8807 
8808       if (symbol_is_section)
8809 	{
8810 	  if (!resolve_section (symbuf, flinfo->output_bfd->sections, result, input_bfd)
8811 	      && !resolve_symbol (symbuf, input_bfd, flinfo, result,
8812 				  isymbuf, locsymcount))
8813 	    {
8814 	      undefined_reference ("section", symbuf);
8815 	      return false;
8816 	    }
8817 	}
8818       else
8819 	{
8820 	  if (!resolve_symbol (symbuf, input_bfd, flinfo, result,
8821 			       isymbuf, locsymcount)
8822 	      && !resolve_section (symbuf, flinfo->output_bfd->sections,
8823 				   result, input_bfd))
8824 	    {
8825 	      undefined_reference ("symbol", symbuf);
8826 	      return false;
8827 	    }
8828 	}
8829 
8830       return true;
8831 
8832       /* All that remains are operators.  */
8833 
8834 #define UNARY_OP(op)						\
8835   if (startswith (sym, #op))					\
8836     {								\
8837       sym += strlen (#op);					\
8838       if (*sym == ':')						\
8839 	++sym;							\
8840       *symp = sym;						\
8841       if (!eval_symbol (&a, symp, input_bfd, flinfo, dot,	\
8842 			isymbuf, locsymcount, signed_p))	\
8843 	return false;						\
8844       if (signed_p)						\
8845 	*result = op ((bfd_signed_vma) a);			\
8846       else							\
8847 	*result = op a;						\
8848       return true;						\
8849     }
8850 
8851 #define BINARY_OP_HEAD(op)					\
8852   if (startswith (sym, #op))					\
8853     {								\
8854       sym += strlen (#op);					\
8855       if (*sym == ':')						\
8856 	++sym;							\
8857       *symp = sym;						\
8858       if (!eval_symbol (&a, symp, input_bfd, flinfo, dot,	\
8859 			isymbuf, locsymcount, signed_p))	\
8860 	return false;						\
8861       ++*symp;							\
8862       if (!eval_symbol (&b, symp, input_bfd, flinfo, dot,	\
8863 			isymbuf, locsymcount, signed_p))	\
8864 	return false;
8865 #define BINARY_OP_TAIL(op)					\
8866       if (signed_p)						\
8867 	*result = ((bfd_signed_vma) a) op ((bfd_signed_vma) b);	\
8868       else							\
8869 	*result = a op b;					\
8870       return true;						\
8871     }
8872 #define BINARY_OP(op) BINARY_OP_HEAD(op) BINARY_OP_TAIL(op)
8873 
8874     default:
8875       UNARY_OP  (0-);
8876       BINARY_OP_HEAD (<<);
8877       if (b >= sizeof (a) * CHAR_BIT)
8878 	{
8879 	  *result = 0;
8880 	  return true;
8881 	}
8882       signed_p = 0;
8883       BINARY_OP_TAIL (<<);
8884       BINARY_OP_HEAD (>>);
8885       if (b >= sizeof (a) * CHAR_BIT)
8886 	{
8887 	  *result = signed_p && (bfd_signed_vma) a < 0 ? -1 : 0;
8888 	  return true;
8889 	}
8890       BINARY_OP_TAIL (>>);
8891       BINARY_OP (==);
8892       BINARY_OP (!=);
8893       BINARY_OP (<=);
8894       BINARY_OP (>=);
8895       BINARY_OP (&&);
8896       BINARY_OP (||);
8897       UNARY_OP  (~);
8898       UNARY_OP  (!);
8899       BINARY_OP (*);
8900       BINARY_OP_HEAD (/);
8901       if (b == 0)
8902 	{
8903 	  _bfd_error_handler (_("division by zero"));
8904 	  bfd_set_error (bfd_error_bad_value);
8905 	  return false;
8906 	}
8907       BINARY_OP_TAIL (/);
8908       BINARY_OP_HEAD (%);
8909       if (b == 0)
8910 	{
8911 	  _bfd_error_handler (_("division by zero"));
8912 	  bfd_set_error (bfd_error_bad_value);
8913 	  return false;
8914 	}
8915       BINARY_OP_TAIL (%);
8916       BINARY_OP (^);
8917       BINARY_OP (|);
8918       BINARY_OP (&);
8919       BINARY_OP (+);
8920       BINARY_OP (-);
8921       BINARY_OP (<);
8922       BINARY_OP (>);
8923 #undef UNARY_OP
8924 #undef BINARY_OP
8925       _bfd_error_handler (_("unknown operator '%c' in complex symbol"), * sym);
8926       bfd_set_error (bfd_error_invalid_operation);
8927       return false;
8928     }
8929 }
8930 
8931 static void
put_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_vma x,bfd_byte * location)8932 put_value (bfd_vma size,
8933 	   unsigned long chunksz,
8934 	   bfd *input_bfd,
8935 	   bfd_vma x,
8936 	   bfd_byte *location)
8937 {
8938   location += (size - chunksz);
8939 
8940   for (; size; size -= chunksz, location -= chunksz)
8941     {
8942       switch (chunksz)
8943 	{
8944 	case 1:
8945 	  bfd_put_8 (input_bfd, x, location);
8946 	  x >>= 8;
8947 	  break;
8948 	case 2:
8949 	  bfd_put_16 (input_bfd, x, location);
8950 	  x >>= 16;
8951 	  break;
8952 	case 4:
8953 	  bfd_put_32 (input_bfd, x, location);
8954 	  /* Computed this way because x >>= 32 is undefined if x is a 32-bit value.  */
8955 	  x >>= 16;
8956 	  x >>= 16;
8957 	  break;
8958 #ifdef BFD64
8959 	case 8:
8960 	  bfd_put_64 (input_bfd, x, location);
8961 	  /* Computed this way because x >>= 64 is undefined if x is a 64-bit value.  */
8962 	  x >>= 32;
8963 	  x >>= 32;
8964 	  break;
8965 #endif
8966 	default:
8967 	  abort ();
8968 	  break;
8969 	}
8970     }
8971 }
8972 
8973 static bfd_vma
get_value(bfd_vma size,unsigned long chunksz,bfd * input_bfd,bfd_byte * location)8974 get_value (bfd_vma size,
8975 	   unsigned long chunksz,
8976 	   bfd *input_bfd,
8977 	   bfd_byte *location)
8978 {
8979   int shift;
8980   bfd_vma x = 0;
8981 
8982   /* Sanity checks.  */
8983   BFD_ASSERT (chunksz <= sizeof (x)
8984 	      && size >= chunksz
8985 	      && chunksz != 0
8986 	      && (size % chunksz) == 0
8987 	      && input_bfd != NULL
8988 	      && location != NULL);
8989 
8990   if (chunksz == sizeof (x))
8991     {
8992       BFD_ASSERT (size == chunksz);
8993 
8994       /* Make sure that we do not perform an undefined shift operation.
8995 	 We know that size == chunksz so there will only be one iteration
8996 	 of the loop below.  */
8997       shift = 0;
8998     }
8999   else
9000     shift = 8 * chunksz;
9001 
9002   for (; size; size -= chunksz, location += chunksz)
9003     {
9004       switch (chunksz)
9005 	{
9006 	case 1:
9007 	  x = (x << shift) | bfd_get_8 (input_bfd, location);
9008 	  break;
9009 	case 2:
9010 	  x = (x << shift) | bfd_get_16 (input_bfd, location);
9011 	  break;
9012 	case 4:
9013 	  x = (x << shift) | bfd_get_32 (input_bfd, location);
9014 	  break;
9015 #ifdef BFD64
9016 	case 8:
9017 	  x = (x << shift) | bfd_get_64 (input_bfd, location);
9018 	  break;
9019 #endif
9020 	default:
9021 	  abort ();
9022 	}
9023     }
9024   return x;
9025 }
9026 
9027 static void
decode_complex_addend(unsigned long * start,unsigned long * oplen,unsigned long * len,unsigned long * wordsz,unsigned long * chunksz,unsigned long * lsb0_p,unsigned long * signed_p,unsigned long * trunc_p,unsigned long encoded)9028 decode_complex_addend (unsigned long *start,   /* in bits */
9029 		       unsigned long *oplen,   /* in bits */
9030 		       unsigned long *len,     /* in bits */
9031 		       unsigned long *wordsz,  /* in bytes */
9032 		       unsigned long *chunksz, /* in bytes */
9033 		       unsigned long *lsb0_p,
9034 		       unsigned long *signed_p,
9035 		       unsigned long *trunc_p,
9036 		       unsigned long encoded)
9037 {
9038   * start     =	 encoded	& 0x3F;
9039   * len	      = (encoded >>  6) & 0x3F;
9040   * oplen     = (encoded >> 12) & 0x3F;
9041   * wordsz    = (encoded >> 18) & 0xF;
9042   * chunksz   = (encoded >> 22) & 0xF;
9043   * lsb0_p    = (encoded >> 27) & 1;
9044   * signed_p  = (encoded >> 28) & 1;
9045   * trunc_p   = (encoded >> 29) & 1;
9046 }
9047 
9048 bfd_reloc_status_type
bfd_elf_perform_complex_relocation(bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * rel,bfd_vma relocation)9049 bfd_elf_perform_complex_relocation (bfd *input_bfd,
9050 				    asection *input_section,
9051 				    bfd_byte *contents,
9052 				    Elf_Internal_Rela *rel,
9053 				    bfd_vma relocation)
9054 {
9055   bfd_vma shift, x, mask;
9056   unsigned long start, oplen, len, wordsz, chunksz, lsb0_p, signed_p, trunc_p;
9057   bfd_reloc_status_type r;
9058   bfd_size_type octets;
9059 
9060   /*  Perform this reloc, since it is complex.
9061       (this is not to say that it necessarily refers to a complex
9062       symbol; merely that it is a self-describing CGEN based reloc.
9063       i.e. the addend has the complete reloc information (bit start, end,
9064       word size, etc) encoded within it.).  */
9065 
9066   decode_complex_addend (&start, &oplen, &len, &wordsz,
9067 			 &chunksz, &lsb0_p, &signed_p,
9068 			 &trunc_p, rel->r_addend);
9069 
9070   mask = (((1L << (len - 1)) - 1) << 1) | 1;
9071 
9072   if (lsb0_p)
9073     shift = (start + 1) - len;
9074   else
9075     shift = (8 * wordsz) - (start + len);
9076 
9077   octets = rel->r_offset * bfd_octets_per_byte (input_bfd, input_section);
9078   x = get_value (wordsz, chunksz, input_bfd, contents + octets);
9079 
9080 #ifdef DEBUG
9081   printf ("Doing complex reloc: "
9082 	  "lsb0? %ld, signed? %ld, trunc? %ld, wordsz %ld, "
9083 	  "chunksz %ld, start %ld, len %ld, oplen %ld\n"
9084 	  "    dest: %8.8lx, mask: %8.8lx, reloc: %8.8lx\n",
9085 	  lsb0_p, signed_p, trunc_p, wordsz, chunksz, start, len,
9086 	  oplen, (unsigned long) x, (unsigned long) mask,
9087 	  (unsigned long) relocation);
9088 #endif
9089 
9090   r = bfd_reloc_ok;
9091   if (! trunc_p)
9092     /* Now do an overflow check.  */
9093     r = bfd_check_overflow ((signed_p
9094 			     ? complain_overflow_signed
9095 			     : complain_overflow_unsigned),
9096 			    len, 0, (8 * wordsz),
9097 			    relocation);
9098 
9099   /* Do the deed.  */
9100   x = (x & ~(mask << shift)) | ((relocation & mask) << shift);
9101 
9102 #ifdef DEBUG
9103   printf ("           relocation: %8.8lx\n"
9104 	  "         shifted mask: %8.8lx\n"
9105 	  " shifted/masked reloc: %8.8lx\n"
9106 	  "               result: %8.8lx\n",
9107 	  (unsigned long) relocation, (unsigned long) (mask << shift),
9108 	  (unsigned long) ((relocation & mask) << shift), (unsigned long) x);
9109 #endif
9110   put_value (wordsz, chunksz, input_bfd, x, contents + octets);
9111   return r;
9112 }
9113 
9114 /* Functions to read r_offset from external (target order) reloc
9115    entry.  Faster than bfd_getl32 et al, because we let the compiler
9116    know the value is aligned.  */
9117 
9118 static bfd_vma
ext32l_r_offset(const void * p)9119 ext32l_r_offset (const void *p)
9120 {
9121   union aligned32
9122   {
9123     uint32_t v;
9124     unsigned char c[4];
9125   };
9126   const union aligned32 *a
9127     = (const union aligned32 *) &((const Elf32_External_Rel *) p)->r_offset;
9128 
9129   uint32_t aval = (  (uint32_t) a->c[0]
9130 		   | (uint32_t) a->c[1] << 8
9131 		   | (uint32_t) a->c[2] << 16
9132 		   | (uint32_t) a->c[3] << 24);
9133   return aval;
9134 }
9135 
9136 static bfd_vma
ext32b_r_offset(const void * p)9137 ext32b_r_offset (const void *p)
9138 {
9139   union aligned32
9140   {
9141     uint32_t v;
9142     unsigned char c[4];
9143   };
9144   const union aligned32 *a
9145     = (const union aligned32 *) &((const Elf32_External_Rel *) p)->r_offset;
9146 
9147   uint32_t aval = (  (uint32_t) a->c[0] << 24
9148 		   | (uint32_t) a->c[1] << 16
9149 		   | (uint32_t) a->c[2] << 8
9150 		   | (uint32_t) a->c[3]);
9151   return aval;
9152 }
9153 
9154 #ifdef BFD_HOST_64_BIT
9155 static bfd_vma
ext64l_r_offset(const void * p)9156 ext64l_r_offset (const void *p)
9157 {
9158   union aligned64
9159   {
9160     uint64_t v;
9161     unsigned char c[8];
9162   };
9163   const union aligned64 *a
9164     = (const union aligned64 *) &((const Elf64_External_Rel *) p)->r_offset;
9165 
9166   uint64_t aval = (  (uint64_t) a->c[0]
9167 		   | (uint64_t) a->c[1] << 8
9168 		   | (uint64_t) a->c[2] << 16
9169 		   | (uint64_t) a->c[3] << 24
9170 		   | (uint64_t) a->c[4] << 32
9171 		   | (uint64_t) a->c[5] << 40
9172 		   | (uint64_t) a->c[6] << 48
9173 		   | (uint64_t) a->c[7] << 56);
9174   return aval;
9175 }
9176 
9177 static bfd_vma
ext64b_r_offset(const void * p)9178 ext64b_r_offset (const void *p)
9179 {
9180   union aligned64
9181   {
9182     uint64_t v;
9183     unsigned char c[8];
9184   };
9185   const union aligned64 *a
9186     = (const union aligned64 *) &((const Elf64_External_Rel *) p)->r_offset;
9187 
9188   uint64_t aval = (  (uint64_t) a->c[0] << 56
9189 		   | (uint64_t) a->c[1] << 48
9190 		   | (uint64_t) a->c[2] << 40
9191 		   | (uint64_t) a->c[3] << 32
9192 		   | (uint64_t) a->c[4] << 24
9193 		   | (uint64_t) a->c[5] << 16
9194 		   | (uint64_t) a->c[6] << 8
9195 		   | (uint64_t) a->c[7]);
9196   return aval;
9197 }
9198 #endif
9199 
9200 /* When performing a relocatable link, the input relocations are
9201    preserved.  But, if they reference global symbols, the indices
9202    referenced must be updated.  Update all the relocations found in
9203    RELDATA.  */
9204 
9205 static bool
elf_link_adjust_relocs(bfd * abfd,asection * sec,struct bfd_elf_section_reloc_data * reldata,bool sort,struct bfd_link_info * info)9206 elf_link_adjust_relocs (bfd *abfd,
9207 			asection *sec,
9208 			struct bfd_elf_section_reloc_data *reldata,
9209 			bool sort,
9210 			struct bfd_link_info *info)
9211 {
9212   unsigned int i;
9213   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9214   bfd_byte *erela;
9215   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
9216   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
9217   bfd_vma r_type_mask;
9218   int r_sym_shift;
9219   unsigned int count = reldata->count;
9220   struct elf_link_hash_entry **rel_hash = reldata->hashes;
9221 
9222   if (reldata->hdr->sh_entsize == bed->s->sizeof_rel)
9223     {
9224       swap_in = bed->s->swap_reloc_in;
9225       swap_out = bed->s->swap_reloc_out;
9226     }
9227   else if (reldata->hdr->sh_entsize == bed->s->sizeof_rela)
9228     {
9229       swap_in = bed->s->swap_reloca_in;
9230       swap_out = bed->s->swap_reloca_out;
9231     }
9232   else
9233     abort ();
9234 
9235   if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
9236     abort ();
9237 
9238   if (bed->s->arch_size == 32)
9239     {
9240       r_type_mask = 0xff;
9241       r_sym_shift = 8;
9242     }
9243   else
9244     {
9245       r_type_mask = 0xffffffff;
9246       r_sym_shift = 32;
9247     }
9248 
9249   erela = reldata->hdr->contents;
9250   for (i = 0; i < count; i++, rel_hash++, erela += reldata->hdr->sh_entsize)
9251     {
9252       Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
9253       unsigned int j;
9254 
9255       if (*rel_hash == NULL)
9256 	continue;
9257 
9258       if ((*rel_hash)->indx == -2
9259 	  && info->gc_sections
9260 	  && ! info->gc_keep_exported)
9261 	{
9262 	  /* PR 21524: Let the user know if a symbol was removed by garbage collection.  */
9263 	  _bfd_error_handler (_("%pB:%pA: error: relocation references symbol %s which was removed by garbage collection"),
9264 			      abfd, sec,
9265 			      (*rel_hash)->root.root.string);
9266 	  _bfd_error_handler (_("%pB:%pA: error: try relinking with --gc-keep-exported enabled"),
9267 			      abfd, sec);
9268 	  bfd_set_error (bfd_error_invalid_operation);
9269 	  return false;
9270 	}
9271       BFD_ASSERT ((*rel_hash)->indx >= 0);
9272 
9273       (*swap_in) (abfd, erela, irela);
9274       for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
9275 	irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
9276 			   | (irela[j].r_info & r_type_mask));
9277       (*swap_out) (abfd, irela, erela);
9278     }
9279 
9280   if (bed->elf_backend_update_relocs)
9281     (*bed->elf_backend_update_relocs) (sec, reldata);
9282 
9283   if (sort && count != 0)
9284     {
9285       bfd_vma (*ext_r_off) (const void *);
9286       bfd_vma r_off;
9287       size_t elt_size;
9288       bfd_byte *base, *end, *p, *loc;
9289       bfd_byte *buf = NULL;
9290 
9291       if (bed->s->arch_size == 32)
9292 	{
9293 	  if (abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)
9294 	    ext_r_off = ext32l_r_offset;
9295 	  else if (abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
9296 	    ext_r_off = ext32b_r_offset;
9297 	  else
9298 	    abort ();
9299 	}
9300       else
9301 	{
9302 #ifdef BFD_HOST_64_BIT
9303 	  if (abfd->xvec->header_byteorder == BFD_ENDIAN_LITTLE)
9304 	    ext_r_off = ext64l_r_offset;
9305 	  else if (abfd->xvec->header_byteorder == BFD_ENDIAN_BIG)
9306 	    ext_r_off = ext64b_r_offset;
9307 	  else
9308 #endif
9309 	    abort ();
9310 	}
9311 
9312       /*  Must use a stable sort here.  A modified insertion sort,
9313 	  since the relocs are mostly sorted already.  */
9314       elt_size = reldata->hdr->sh_entsize;
9315       base = reldata->hdr->contents;
9316       end = base + count * elt_size;
9317       if (elt_size > sizeof (Elf64_External_Rela))
9318 	abort ();
9319 
9320       /* Ensure the first element is lowest.  This acts as a sentinel,
9321 	 speeding the main loop below.  */
9322       r_off = (*ext_r_off) (base);
9323       for (p = loc = base; (p += elt_size) < end; )
9324 	{
9325 	  bfd_vma r_off2 = (*ext_r_off) (p);
9326 	  if (r_off > r_off2)
9327 	    {
9328 	      r_off = r_off2;
9329 	      loc = p;
9330 	    }
9331 	}
9332       if (loc != base)
9333 	{
9334 	  /* Don't just swap *base and *loc as that changes the order
9335 	     of the original base[0] and base[1] if they happen to
9336 	     have the same r_offset.  */
9337 	  bfd_byte onebuf[sizeof (Elf64_External_Rela)];
9338 	  memcpy (onebuf, loc, elt_size);
9339 	  memmove (base + elt_size, base, loc - base);
9340 	  memcpy (base, onebuf, elt_size);
9341 	}
9342 
9343       for (p = base + elt_size; (p += elt_size) < end; )
9344 	{
9345 	  /* base to p is sorted, *p is next to insert.  */
9346 	  r_off = (*ext_r_off) (p);
9347 	  /* Search the sorted region for location to insert.  */
9348 	  loc = p - elt_size;
9349 	  while (r_off < (*ext_r_off) (loc))
9350 	    loc -= elt_size;
9351 	  loc += elt_size;
9352 	  if (loc != p)
9353 	    {
9354 	      /* Chances are there is a run of relocs to insert here,
9355 		 from one of more input files.  Files are not always
9356 		 linked in order due to the way elf_link_input_bfd is
9357 		 called.  See pr17666.  */
9358 	      size_t sortlen = p - loc;
9359 	      bfd_vma r_off2 = (*ext_r_off) (loc);
9360 	      size_t runlen = elt_size;
9361 	      size_t buf_size = 96 * 1024;
9362 	      while (p + runlen < end
9363 		     && (sortlen <= buf_size
9364 			 || runlen + elt_size <= buf_size)
9365 		     && r_off2 > (*ext_r_off) (p + runlen))
9366 		runlen += elt_size;
9367 	      if (buf == NULL)
9368 		{
9369 		  buf = bfd_malloc (buf_size);
9370 		  if (buf == NULL)
9371 		    return false;
9372 		}
9373 	      if (runlen < sortlen)
9374 		{
9375 		  memcpy (buf, p, runlen);
9376 		  memmove (loc + runlen, loc, sortlen);
9377 		  memcpy (loc, buf, runlen);
9378 		}
9379 	      else
9380 		{
9381 		  memcpy (buf, loc, sortlen);
9382 		  memmove (loc, p, runlen);
9383 		  memcpy (loc + runlen, buf, sortlen);
9384 		}
9385 	      p += runlen - elt_size;
9386 	    }
9387 	}
9388       /* Hashes are no longer valid.  */
9389       free (reldata->hashes);
9390       reldata->hashes = NULL;
9391       free (buf);
9392     }
9393   return true;
9394 }
9395 
9396 struct elf_link_sort_rela
9397 {
9398   union {
9399     bfd_vma offset;
9400     bfd_vma sym_mask;
9401   } u;
9402   enum elf_reloc_type_class type;
9403   /* We use this as an array of size int_rels_per_ext_rel.  */
9404   Elf_Internal_Rela rela[1];
9405 };
9406 
9407 /* qsort stability here and for cmp2 is only an issue if multiple
9408    dynamic relocations are emitted at the same address.  But targets
9409    that apply a series of dynamic relocations each operating on the
9410    result of the prior relocation can't use -z combreloc as
9411    implemented anyway.  Such schemes tend to be broken by sorting on
9412    symbol index.  That leaves dynamic NONE relocs as the only other
9413    case where ld might emit multiple relocs at the same address, and
9414    those are only emitted due to target bugs.  */
9415 
9416 static int
elf_link_sort_cmp1(const void * A,const void * B)9417 elf_link_sort_cmp1 (const void *A, const void *B)
9418 {
9419   const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
9420   const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
9421   int relativea, relativeb;
9422 
9423   relativea = a->type == reloc_class_relative;
9424   relativeb = b->type == reloc_class_relative;
9425 
9426   if (relativea < relativeb)
9427     return 1;
9428   if (relativea > relativeb)
9429     return -1;
9430   if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
9431     return -1;
9432   if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
9433     return 1;
9434   if (a->rela->r_offset < b->rela->r_offset)
9435     return -1;
9436   if (a->rela->r_offset > b->rela->r_offset)
9437     return 1;
9438   return 0;
9439 }
9440 
9441 static int
elf_link_sort_cmp2(const void * A,const void * B)9442 elf_link_sort_cmp2 (const void *A, const void *B)
9443 {
9444   const struct elf_link_sort_rela *a = (const struct elf_link_sort_rela *) A;
9445   const struct elf_link_sort_rela *b = (const struct elf_link_sort_rela *) B;
9446 
9447   if (a->type < b->type)
9448     return -1;
9449   if (a->type > b->type)
9450     return 1;
9451   if (a->u.offset < b->u.offset)
9452     return -1;
9453   if (a->u.offset > b->u.offset)
9454     return 1;
9455   if (a->rela->r_offset < b->rela->r_offset)
9456     return -1;
9457   if (a->rela->r_offset > b->rela->r_offset)
9458     return 1;
9459   return 0;
9460 }
9461 
9462 static size_t
elf_link_sort_relocs(bfd * abfd,struct bfd_link_info * info,asection ** psec)9463 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
9464 {
9465   asection *dynamic_relocs;
9466   asection *rela_dyn;
9467   asection *rel_dyn;
9468   bfd_size_type count, size;
9469   size_t i, ret, sort_elt, ext_size;
9470   bfd_byte *sort, *s_non_relative, *p;
9471   struct elf_link_sort_rela *sq;
9472   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9473   int i2e = bed->s->int_rels_per_ext_rel;
9474   unsigned int opb = bfd_octets_per_byte (abfd, NULL);
9475   void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
9476   void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
9477   struct bfd_link_order *lo;
9478   bfd_vma r_sym_mask;
9479   bool use_rela;
9480 
9481   /* Find a dynamic reloc section.  */
9482   rela_dyn = bfd_get_section_by_name (abfd, ".rela.dyn");
9483   rel_dyn  = bfd_get_section_by_name (abfd, ".rel.dyn");
9484   if (rela_dyn != NULL && rela_dyn->size > 0
9485       && rel_dyn != NULL && rel_dyn->size > 0)
9486     {
9487       bool use_rela_initialised = false;
9488 
9489       /* This is just here to stop gcc from complaining.
9490 	 Its initialization checking code is not perfect.  */
9491       use_rela = true;
9492 
9493       /* Both sections are present.  Examine the sizes
9494 	 of the indirect sections to help us choose.  */
9495       for (lo = rela_dyn->map_head.link_order; lo != NULL; lo = lo->next)
9496 	if (lo->type == bfd_indirect_link_order)
9497 	  {
9498 	    asection *o = lo->u.indirect.section;
9499 
9500 	    if ((o->size % bed->s->sizeof_rela) == 0)
9501 	      {
9502 		if ((o->size % bed->s->sizeof_rel) == 0)
9503 		  /* Section size is divisible by both rel and rela sizes.
9504 		     It is of no help to us.  */
9505 		  ;
9506 		else
9507 		  {
9508 		    /* Section size is only divisible by rela.  */
9509 		    if (use_rela_initialised && !use_rela)
9510 		      {
9511 			_bfd_error_handler (_("%pB: unable to sort relocs - "
9512 					      "they are in more than one size"),
9513 					    abfd);
9514 			bfd_set_error (bfd_error_invalid_operation);
9515 			return 0;
9516 		      }
9517 		    else
9518 		      {
9519 			use_rela = true;
9520 			use_rela_initialised = true;
9521 		      }
9522 		  }
9523 	      }
9524 	    else if ((o->size % bed->s->sizeof_rel) == 0)
9525 	      {
9526 		/* Section size is only divisible by rel.  */
9527 		if (use_rela_initialised && use_rela)
9528 		  {
9529 		    _bfd_error_handler (_("%pB: unable to sort relocs - "
9530 					  "they are in more than one size"),
9531 					abfd);
9532 		    bfd_set_error (bfd_error_invalid_operation);
9533 		    return 0;
9534 		  }
9535 		else
9536 		  {
9537 		    use_rela = false;
9538 		    use_rela_initialised = true;
9539 		  }
9540 	      }
9541 	    else
9542 	      {
9543 		/* The section size is not divisible by either -
9544 		   something is wrong.  */
9545 		_bfd_error_handler (_("%pB: unable to sort relocs - "
9546 				      "they are of an unknown size"), abfd);
9547 		bfd_set_error (bfd_error_invalid_operation);
9548 		return 0;
9549 	      }
9550 	  }
9551 
9552       for (lo = rel_dyn->map_head.link_order; lo != NULL; lo = lo->next)
9553 	if (lo->type == bfd_indirect_link_order)
9554 	  {
9555 	    asection *o = lo->u.indirect.section;
9556 
9557 	    if ((o->size % bed->s->sizeof_rela) == 0)
9558 	      {
9559 		if ((o->size % bed->s->sizeof_rel) == 0)
9560 		  /* Section size is divisible by both rel and rela sizes.
9561 		     It is of no help to us.  */
9562 		  ;
9563 		else
9564 		  {
9565 		    /* Section size is only divisible by rela.  */
9566 		    if (use_rela_initialised && !use_rela)
9567 		      {
9568 			_bfd_error_handler (_("%pB: unable to sort relocs - "
9569 					      "they are in more than one size"),
9570 					    abfd);
9571 			bfd_set_error (bfd_error_invalid_operation);
9572 			return 0;
9573 		      }
9574 		    else
9575 		      {
9576 			use_rela = true;
9577 			use_rela_initialised = true;
9578 		      }
9579 		  }
9580 	      }
9581 	    else if ((o->size % bed->s->sizeof_rel) == 0)
9582 	      {
9583 		/* Section size is only divisible by rel.  */
9584 		if (use_rela_initialised && use_rela)
9585 		  {
9586 		    _bfd_error_handler (_("%pB: unable to sort relocs - "
9587 					  "they are in more than one size"),
9588 					abfd);
9589 		    bfd_set_error (bfd_error_invalid_operation);
9590 		    return 0;
9591 		  }
9592 		else
9593 		  {
9594 		    use_rela = false;
9595 		    use_rela_initialised = true;
9596 		  }
9597 	      }
9598 	    else
9599 	      {
9600 		/* The section size is not divisible by either -
9601 		   something is wrong.  */
9602 		_bfd_error_handler (_("%pB: unable to sort relocs - "
9603 				      "they are of an unknown size"), abfd);
9604 		bfd_set_error (bfd_error_invalid_operation);
9605 		return 0;
9606 	      }
9607 	  }
9608 
9609       if (! use_rela_initialised)
9610 	/* Make a guess.  */
9611 	use_rela = true;
9612     }
9613   else if (rela_dyn != NULL && rela_dyn->size > 0)
9614     use_rela = true;
9615   else if (rel_dyn != NULL && rel_dyn->size > 0)
9616     use_rela = false;
9617   else
9618     return 0;
9619 
9620   if (use_rela)
9621     {
9622       dynamic_relocs = rela_dyn;
9623       ext_size = bed->s->sizeof_rela;
9624       swap_in = bed->s->swap_reloca_in;
9625       swap_out = bed->s->swap_reloca_out;
9626     }
9627   else
9628     {
9629       dynamic_relocs = rel_dyn;
9630       ext_size = bed->s->sizeof_rel;
9631       swap_in = bed->s->swap_reloc_in;
9632       swap_out = bed->s->swap_reloc_out;
9633     }
9634 
9635   size = 0;
9636   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
9637     if (lo->type == bfd_indirect_link_order)
9638       size += lo->u.indirect.section->size;
9639 
9640   if (size != dynamic_relocs->size)
9641     return 0;
9642 
9643   sort_elt = (sizeof (struct elf_link_sort_rela)
9644 	      + (i2e - 1) * sizeof (Elf_Internal_Rela));
9645 
9646   count = dynamic_relocs->size / ext_size;
9647   if (count == 0)
9648     return 0;
9649   sort = (bfd_byte *) bfd_zmalloc (sort_elt * count);
9650 
9651   if (sort == NULL)
9652     {
9653       (*info->callbacks->warning)
9654 	(info, _("not enough memory to sort relocations"), 0, abfd, 0, 0);
9655       return 0;
9656     }
9657 
9658   if (bed->s->arch_size == 32)
9659     r_sym_mask = ~(bfd_vma) 0xff;
9660   else
9661     r_sym_mask = ~(bfd_vma) 0xffffffff;
9662 
9663   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
9664     if (lo->type == bfd_indirect_link_order)
9665       {
9666 	bfd_byte *erel, *erelend;
9667 	asection *o = lo->u.indirect.section;
9668 
9669 	if (o->contents == NULL && o->size != 0)
9670 	  {
9671 	    /* This is a reloc section that is being handled as a normal
9672 	       section.  See bfd_section_from_shdr.  We can't combine
9673 	       relocs in this case.  */
9674 	    free (sort);
9675 	    return 0;
9676 	  }
9677 	erel = o->contents;
9678 	erelend = o->contents + o->size;
9679 	p = sort + o->output_offset * opb / ext_size * sort_elt;
9680 
9681 	while (erel < erelend)
9682 	  {
9683 	    struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
9684 
9685 	    (*swap_in) (abfd, erel, s->rela);
9686 	    s->type = (*bed->elf_backend_reloc_type_class) (info, o, s->rela);
9687 	    s->u.sym_mask = r_sym_mask;
9688 	    p += sort_elt;
9689 	    erel += ext_size;
9690 	  }
9691       }
9692 
9693   qsort (sort, count, sort_elt, elf_link_sort_cmp1);
9694 
9695   for (i = 0, p = sort; i < count; i++, p += sort_elt)
9696     {
9697       struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
9698       if (s->type != reloc_class_relative)
9699 	break;
9700     }
9701   ret = i;
9702   s_non_relative = p;
9703 
9704   sq = (struct elf_link_sort_rela *) s_non_relative;
9705   for (; i < count; i++, p += sort_elt)
9706     {
9707       struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
9708       if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
9709 	sq = sp;
9710       sp->u.offset = sq->rela->r_offset;
9711     }
9712 
9713   qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
9714 
9715   struct elf_link_hash_table *htab = elf_hash_table (info);
9716   if (htab->srelplt && htab->srelplt->output_section == dynamic_relocs)
9717     {
9718       /* We have plt relocs in .rela.dyn.  */
9719       sq = (struct elf_link_sort_rela *) sort;
9720       for (i = 0; i < count; i++)
9721 	if (sq[count - i - 1].type != reloc_class_plt)
9722 	  break;
9723       if (i != 0 && htab->srelplt->size == i * ext_size)
9724 	{
9725 	  struct bfd_link_order **plo;
9726 	  /* Put srelplt link_order last.  This is so the output_offset
9727 	     set in the next loop is correct for DT_JMPREL.  */
9728 	  for (plo = &dynamic_relocs->map_head.link_order; *plo != NULL; )
9729 	    if ((*plo)->type == bfd_indirect_link_order
9730 		&& (*plo)->u.indirect.section == htab->srelplt)
9731 	      {
9732 		lo = *plo;
9733 		*plo = lo->next;
9734 	      }
9735 	    else
9736 	      plo = &(*plo)->next;
9737 	  *plo = lo;
9738 	  lo->next = NULL;
9739 	  dynamic_relocs->map_tail.link_order = lo;
9740 	}
9741     }
9742 
9743   p = sort;
9744   for (lo = dynamic_relocs->map_head.link_order; lo != NULL; lo = lo->next)
9745     if (lo->type == bfd_indirect_link_order)
9746       {
9747 	bfd_byte *erel, *erelend;
9748 	asection *o = lo->u.indirect.section;
9749 
9750 	erel = o->contents;
9751 	erelend = o->contents + o->size;
9752 	o->output_offset = (p - sort) / sort_elt * ext_size / opb;
9753 	while (erel < erelend)
9754 	  {
9755 	    struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
9756 	    (*swap_out) (abfd, s->rela, erel);
9757 	    p += sort_elt;
9758 	    erel += ext_size;
9759 	  }
9760       }
9761 
9762   free (sort);
9763   *psec = dynamic_relocs;
9764   return ret;
9765 }
9766 
9767 /* Add a symbol to the output symbol string table.  */
9768 
9769 static int
elf_link_output_symstrtab(void * finf,const char * name,Elf_Internal_Sym * elfsym,asection * input_sec,struct elf_link_hash_entry * h)9770 elf_link_output_symstrtab (void *finf,
9771 			   const char *name,
9772 			   Elf_Internal_Sym *elfsym,
9773 			   asection *input_sec,
9774 			   struct elf_link_hash_entry *h)
9775 {
9776   struct elf_final_link_info *flinfo = finf;
9777   int (*output_symbol_hook)
9778     (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
9779      struct elf_link_hash_entry *);
9780   struct elf_link_hash_table *hash_table;
9781   const struct elf_backend_data *bed;
9782   bfd_size_type strtabsize;
9783 
9784   BFD_ASSERT (elf_onesymtab (flinfo->output_bfd));
9785 
9786   bed = get_elf_backend_data (flinfo->output_bfd);
9787   output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
9788   if (output_symbol_hook != NULL)
9789     {
9790       int ret = (*output_symbol_hook) (flinfo->info, name, elfsym, input_sec, h);
9791       if (ret != 1)
9792 	return ret;
9793     }
9794 
9795   if (ELF_ST_TYPE (elfsym->st_info) == STT_GNU_IFUNC)
9796     elf_tdata (flinfo->output_bfd)->has_gnu_osabi |= elf_gnu_osabi_ifunc;
9797   if (ELF_ST_BIND (elfsym->st_info) == STB_GNU_UNIQUE)
9798     elf_tdata (flinfo->output_bfd)->has_gnu_osabi |= elf_gnu_osabi_unique;
9799 
9800   if (name == NULL
9801       || *name == '\0'
9802       || (input_sec->flags & SEC_EXCLUDE))
9803     elfsym->st_name = (unsigned long) -1;
9804   else
9805     {
9806       /* Call _bfd_elf_strtab_offset after _bfd_elf_strtab_finalize
9807 	 to get the final offset for st_name.  */
9808       char *versioned_name = (char *) name;
9809       if (h != NULL)
9810 	{
9811 	  if (h->versioned == versioned && h->def_dynamic)
9812 	    {
9813 	      /* Keep only one '@' for versioned symbols defined in
9814 	         shared objects.  */
9815 	      char *version = strrchr (name, ELF_VER_CHR);
9816 	      char *base_end = strchr (name, ELF_VER_CHR);
9817 	      if (version != base_end)
9818 		{
9819 		  size_t base_len;
9820 		  size_t len = strlen (name);
9821 		  versioned_name = bfd_alloc (flinfo->output_bfd, len);
9822 		  if (versioned_name == NULL)
9823 		    return 0;
9824 		  base_len = base_end - name;
9825 		  memcpy (versioned_name, name, base_len);
9826 		  memcpy (versioned_name + base_len, version,
9827 			  len - base_len);
9828 		}
9829 	    }
9830 	}
9831       else if (flinfo->info->unique_symbol
9832 	       && ELF_ST_BIND (elfsym->st_info) == STB_LOCAL)
9833 	{
9834 	  struct local_hash_entry *lh;
9835 	  size_t count_len;
9836 	  size_t base_len;
9837 	  char buf[30];
9838 	  switch (ELF_ST_TYPE (elfsym->st_info))
9839 	    {
9840 	    case STT_FILE:
9841 	    case STT_SECTION:
9842 	      break;
9843 	    default:
9844 	      lh = (struct local_hash_entry *) bfd_hash_lookup
9845 		     (&flinfo->local_hash_table, name, true, false);
9846 	      if (lh == NULL)
9847 		return 0;
9848 	      /* Always append ".COUNT" to local symbols to avoid
9849 		 potential conflicts with local symbol "XXX.COUNT".  */
9850 	      sprintf (buf, "%lx", lh->count);
9851 	      base_len = lh->size;
9852 	      if (!base_len)
9853 		{
9854 		  base_len = strlen (name);
9855 		  lh->size = base_len;
9856 		}
9857 	      count_len = strlen (buf);
9858 	      versioned_name = bfd_alloc (flinfo->output_bfd,
9859 					  base_len + count_len + 2);
9860 	      if (versioned_name == NULL)
9861 		return 0;
9862 	      memcpy (versioned_name, name, base_len);
9863 	      versioned_name[base_len] = '.';
9864 	      memcpy (versioned_name + base_len + 1, buf,
9865 		      count_len + 1);
9866 	      lh->count++;
9867 	      break;
9868 	    }
9869 	}
9870       elfsym->st_name
9871 	= (unsigned long) _bfd_elf_strtab_add (flinfo->symstrtab,
9872 					       versioned_name, false);
9873       if (elfsym->st_name == (unsigned long) -1)
9874 	return 0;
9875     }
9876 
9877   hash_table = elf_hash_table (flinfo->info);
9878   strtabsize = hash_table->strtabsize;
9879   if (strtabsize <= hash_table->strtabcount)
9880     {
9881       strtabsize += strtabsize;
9882       hash_table->strtabsize = strtabsize;
9883       strtabsize *= sizeof (*hash_table->strtab);
9884       hash_table->strtab
9885 	= (struct elf_sym_strtab *) bfd_realloc (hash_table->strtab,
9886 						 strtabsize);
9887       if (hash_table->strtab == NULL)
9888 	return 0;
9889     }
9890   hash_table->strtab[hash_table->strtabcount].sym = *elfsym;
9891   hash_table->strtab[hash_table->strtabcount].dest_index
9892     = hash_table->strtabcount;
9893   hash_table->strtab[hash_table->strtabcount].destshndx_index
9894     = flinfo->symshndxbuf ? bfd_get_symcount (flinfo->output_bfd) : 0;
9895 
9896   flinfo->output_bfd->symcount += 1;
9897   hash_table->strtabcount += 1;
9898 
9899   return 1;
9900 }
9901 
9902 /* Swap symbols out to the symbol table and flush the output symbols to
9903    the file.  */
9904 
9905 static bool
elf_link_swap_symbols_out(struct elf_final_link_info * flinfo)9906 elf_link_swap_symbols_out (struct elf_final_link_info *flinfo)
9907 {
9908   struct elf_link_hash_table *hash_table = elf_hash_table (flinfo->info);
9909   size_t amt;
9910   size_t i;
9911   const struct elf_backend_data *bed;
9912   bfd_byte *symbuf;
9913   Elf_Internal_Shdr *hdr;
9914   file_ptr pos;
9915   bool ret;
9916 
9917   if (!hash_table->strtabcount)
9918     return true;
9919 
9920   BFD_ASSERT (elf_onesymtab (flinfo->output_bfd));
9921 
9922   bed = get_elf_backend_data (flinfo->output_bfd);
9923 
9924   amt = bed->s->sizeof_sym * hash_table->strtabcount;
9925   symbuf = (bfd_byte *) bfd_malloc (amt);
9926   if (symbuf == NULL)
9927     return false;
9928 
9929   if (flinfo->symshndxbuf)
9930     {
9931       amt = sizeof (Elf_External_Sym_Shndx);
9932       amt *= bfd_get_symcount (flinfo->output_bfd);
9933       flinfo->symshndxbuf = (Elf_External_Sym_Shndx *) bfd_zmalloc (amt);
9934       if (flinfo->symshndxbuf == NULL)
9935 	{
9936 	  free (symbuf);
9937 	  return false;
9938 	}
9939     }
9940 
9941   /* Now swap out the symbols.  */
9942   for (i = 0; i < hash_table->strtabcount; i++)
9943     {
9944       struct elf_sym_strtab *elfsym = &hash_table->strtab[i];
9945       if (elfsym->sym.st_name == (unsigned long) -1)
9946 	elfsym->sym.st_name = 0;
9947       else
9948 	elfsym->sym.st_name
9949 	  = (unsigned long) _bfd_elf_strtab_offset (flinfo->symstrtab,
9950 						    elfsym->sym.st_name);
9951 
9952       /* Inform the linker of the addition of this symbol.  */
9953 
9954       if (flinfo->info->callbacks->ctf_new_symbol)
9955 	flinfo->info->callbacks->ctf_new_symbol (elfsym->dest_index,
9956 						 &elfsym->sym);
9957 
9958       bed->s->swap_symbol_out (flinfo->output_bfd, &elfsym->sym,
9959 			       ((bfd_byte *) symbuf
9960 				+ (elfsym->dest_index
9961 				   * bed->s->sizeof_sym)),
9962 			       (flinfo->symshndxbuf
9963 				+ elfsym->destshndx_index));
9964     }
9965 
9966   hdr = &elf_tdata (flinfo->output_bfd)->symtab_hdr;
9967   pos = hdr->sh_offset + hdr->sh_size;
9968   amt = hash_table->strtabcount * bed->s->sizeof_sym;
9969   if (bfd_seek (flinfo->output_bfd, pos, SEEK_SET) == 0
9970       && bfd_bwrite (symbuf, amt, flinfo->output_bfd) == amt)
9971     {
9972       hdr->sh_size += amt;
9973       ret = true;
9974     }
9975   else
9976     ret = false;
9977 
9978   free (symbuf);
9979 
9980   free (hash_table->strtab);
9981   hash_table->strtab = NULL;
9982 
9983   return ret;
9984 }
9985 
9986 /* Return TRUE if the dynamic symbol SYM in ABFD is supported.  */
9987 
9988 static bool
check_dynsym(bfd * abfd,Elf_Internal_Sym * sym)9989 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
9990 {
9991   if (sym->st_shndx >= (SHN_LORESERVE & 0xffff)
9992       && sym->st_shndx < SHN_LORESERVE)
9993     {
9994       /* The gABI doesn't support dynamic symbols in output sections
9995 	 beyond 64k.  */
9996       _bfd_error_handler
9997 	/* xgettext:c-format */
9998 	(_("%pB: too many sections: %d (>= %d)"),
9999 	 abfd, bfd_count_sections (abfd), SHN_LORESERVE & 0xffff);
10000       bfd_set_error (bfd_error_nonrepresentable_section);
10001       return false;
10002     }
10003   return true;
10004 }
10005 
10006 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
10007    allowing an unsatisfied unversioned symbol in the DSO to match a
10008    versioned symbol that would normally require an explicit version.
10009    We also handle the case that a DSO references a hidden symbol
10010    which may be satisfied by a versioned symbol in another DSO.  */
10011 
10012 static bool
elf_link_check_versioned_symbol(struct bfd_link_info * info,const struct elf_backend_data * bed,struct elf_link_hash_entry * h)10013 elf_link_check_versioned_symbol (struct bfd_link_info *info,
10014 				 const struct elf_backend_data *bed,
10015 				 struct elf_link_hash_entry *h)
10016 {
10017   bfd *abfd;
10018   struct elf_link_loaded_list *loaded;
10019 
10020   if (!is_elf_hash_table (info->hash))
10021     return false;
10022 
10023   /* Check indirect symbol.  */
10024   while (h->root.type == bfd_link_hash_indirect)
10025     h = (struct elf_link_hash_entry *) h->root.u.i.link;
10026 
10027   switch (h->root.type)
10028     {
10029     default:
10030       abfd = NULL;
10031       break;
10032 
10033     case bfd_link_hash_undefined:
10034     case bfd_link_hash_undefweak:
10035       abfd = h->root.u.undef.abfd;
10036       if (abfd == NULL
10037 	  || (abfd->flags & DYNAMIC) == 0
10038 	  || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
10039 	return false;
10040       break;
10041 
10042     case bfd_link_hash_defined:
10043     case bfd_link_hash_defweak:
10044       abfd = h->root.u.def.section->owner;
10045       break;
10046 
10047     case bfd_link_hash_common:
10048       abfd = h->root.u.c.p->section->owner;
10049       break;
10050     }
10051   BFD_ASSERT (abfd != NULL);
10052 
10053   for (loaded = elf_hash_table (info)->dyn_loaded;
10054        loaded != NULL;
10055        loaded = loaded->next)
10056     {
10057       bfd *input;
10058       Elf_Internal_Shdr *hdr;
10059       size_t symcount;
10060       size_t extsymcount;
10061       size_t extsymoff;
10062       Elf_Internal_Shdr *versymhdr;
10063       Elf_Internal_Sym *isym;
10064       Elf_Internal_Sym *isymend;
10065       Elf_Internal_Sym *isymbuf;
10066       Elf_External_Versym *ever;
10067       Elf_External_Versym *extversym;
10068 
10069       input = loaded->abfd;
10070 
10071       /* We check each DSO for a possible hidden versioned definition.  */
10072       if (input == abfd
10073 	  || elf_dynversym (input) == 0)
10074 	continue;
10075 
10076       hdr = &elf_tdata (input)->dynsymtab_hdr;
10077 
10078       symcount = hdr->sh_size / bed->s->sizeof_sym;
10079       if (elf_bad_symtab (input))
10080 	{
10081 	  extsymcount = symcount;
10082 	  extsymoff = 0;
10083 	}
10084       else
10085 	{
10086 	  extsymcount = symcount - hdr->sh_info;
10087 	  extsymoff = hdr->sh_info;
10088 	}
10089 
10090       if (extsymcount == 0)
10091 	continue;
10092 
10093       isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
10094 				      NULL, NULL, NULL);
10095       if (isymbuf == NULL)
10096 	return false;
10097 
10098       /* Read in any version definitions.  */
10099       versymhdr = &elf_tdata (input)->dynversym_hdr;
10100       if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
10101 	  || (extversym = (Elf_External_Versym *)
10102 	      _bfd_malloc_and_read (input, versymhdr->sh_size,
10103 				    versymhdr->sh_size)) == NULL)
10104 	{
10105 	  free (isymbuf);
10106 	  return false;
10107 	}
10108 
10109       ever = extversym + extsymoff;
10110       isymend = isymbuf + extsymcount;
10111       for (isym = isymbuf; isym < isymend; isym++, ever++)
10112 	{
10113 	  const char *name;
10114 	  Elf_Internal_Versym iver;
10115 	  unsigned short version_index;
10116 
10117 	  if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
10118 	      || isym->st_shndx == SHN_UNDEF)
10119 	    continue;
10120 
10121 	  name = bfd_elf_string_from_elf_section (input,
10122 						  hdr->sh_link,
10123 						  isym->st_name);
10124 	  if (strcmp (name, h->root.root.string) != 0)
10125 	    continue;
10126 
10127 	  _bfd_elf_swap_versym_in (input, ever, &iver);
10128 
10129 	  if ((iver.vs_vers & VERSYM_HIDDEN) == 0
10130 	      && !(h->def_regular
10131 		   && h->forced_local))
10132 	    {
10133 	      /* If we have a non-hidden versioned sym, then it should
10134 		 have provided a definition for the undefined sym unless
10135 		 it is defined in a non-shared object and forced local.
10136 	       */
10137 	      abort ();
10138 	    }
10139 
10140 	  version_index = iver.vs_vers & VERSYM_VERSION;
10141 	  if (version_index == 1 || version_index == 2)
10142 	    {
10143 	      /* This is the base or first version.  We can use it.  */
10144 	      free (extversym);
10145 	      free (isymbuf);
10146 	      return true;
10147 	    }
10148 	}
10149 
10150       free (extversym);
10151       free (isymbuf);
10152     }
10153 
10154   return false;
10155 }
10156 
10157 /* Convert ELF common symbol TYPE.  */
10158 
10159 static int
elf_link_convert_common_type(struct bfd_link_info * info,int type)10160 elf_link_convert_common_type (struct bfd_link_info *info, int type)
10161 {
10162   /* Commom symbol can only appear in relocatable link.  */
10163   if (!bfd_link_relocatable (info))
10164     abort ();
10165   switch (info->elf_stt_common)
10166     {
10167     case unchanged:
10168       break;
10169     case elf_stt_common:
10170       type = STT_COMMON;
10171       break;
10172     case no_elf_stt_common:
10173       type = STT_OBJECT;
10174       break;
10175     }
10176   return type;
10177 }
10178 
10179 /* Add an external symbol to the symbol table.  This is called from
10180    the hash table traversal routine.  When generating a shared object,
10181    we go through the symbol table twice.  The first time we output
10182    anything that might have been forced to local scope in a version
10183    script.  The second time we output the symbols that are still
10184    global symbols.  */
10185 
10186 static bool
elf_link_output_extsym(struct bfd_hash_entry * bh,void * data)10187 elf_link_output_extsym (struct bfd_hash_entry *bh, void *data)
10188 {
10189   struct elf_link_hash_entry *h = (struct elf_link_hash_entry *) bh;
10190   struct elf_outext_info *eoinfo = (struct elf_outext_info *) data;
10191   struct elf_final_link_info *flinfo = eoinfo->flinfo;
10192   bool strip;
10193   Elf_Internal_Sym sym;
10194   asection *input_sec;
10195   const struct elf_backend_data *bed;
10196   long indx;
10197   int ret;
10198   unsigned int type;
10199 
10200   if (h->root.type == bfd_link_hash_warning)
10201     {
10202       h = (struct elf_link_hash_entry *) h->root.u.i.link;
10203       if (h->root.type == bfd_link_hash_new)
10204 	return true;
10205     }
10206 
10207   /* Decide whether to output this symbol in this pass.  */
10208   if (eoinfo->localsyms)
10209     {
10210       if (!h->forced_local)
10211 	return true;
10212     }
10213   else
10214     {
10215       if (h->forced_local)
10216 	return true;
10217     }
10218 
10219   bed = get_elf_backend_data (flinfo->output_bfd);
10220 
10221   if (h->root.type == bfd_link_hash_undefined)
10222     {
10223       /* If we have an undefined symbol reference here then it must have
10224 	 come from a shared library that is being linked in.  (Undefined
10225 	 references in regular files have already been handled unless
10226 	 they are in unreferenced sections which are removed by garbage
10227 	 collection).  */
10228       bool ignore_undef = false;
10229 
10230       /* Some symbols may be special in that the fact that they're
10231 	 undefined can be safely ignored - let backend determine that.  */
10232       if (bed->elf_backend_ignore_undef_symbol)
10233 	ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
10234 
10235       /* If we are reporting errors for this situation then do so now.  */
10236       if (!ignore_undef
10237 	  && h->ref_dynamic_nonweak
10238 	  && (!h->ref_regular || flinfo->info->gc_sections)
10239 	  && !elf_link_check_versioned_symbol (flinfo->info, bed, h)
10240 	  && flinfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
10241 	{
10242 	  flinfo->info->callbacks->undefined_symbol
10243 	    (flinfo->info, h->root.root.string,
10244 	     h->ref_regular ? NULL : h->root.u.undef.abfd, NULL, 0,
10245 	     flinfo->info->unresolved_syms_in_shared_libs == RM_DIAGNOSE
10246 	     && !flinfo->info->warn_unresolved_syms);
10247 	}
10248 
10249       /* Strip a global symbol defined in a discarded section.  */
10250       if (h->indx == -3)
10251 	return true;
10252     }
10253 
10254   /* We should also warn if a forced local symbol is referenced from
10255      shared libraries.  */
10256   if (bfd_link_executable (flinfo->info)
10257       && h->forced_local
10258       && h->ref_dynamic
10259       && h->def_regular
10260       && !h->dynamic_def
10261       && h->ref_dynamic_nonweak
10262       && !elf_link_check_versioned_symbol (flinfo->info, bed, h))
10263     {
10264       bfd *def_bfd;
10265       const char *msg;
10266       struct elf_link_hash_entry *hi = h;
10267 
10268       /* Check indirect symbol.  */
10269       while (hi->root.type == bfd_link_hash_indirect)
10270 	hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
10271 
10272       if (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL)
10273 	/* xgettext:c-format */
10274 	msg = _("%pB: internal symbol `%s' in %pB is referenced by DSO");
10275       else if (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN)
10276 	/* xgettext:c-format */
10277 	msg = _("%pB: hidden symbol `%s' in %pB is referenced by DSO");
10278       else
10279 	/* xgettext:c-format */
10280 	msg = _("%pB: local symbol `%s' in %pB is referenced by DSO");
10281       def_bfd = flinfo->output_bfd;
10282       if (hi->root.u.def.section != bfd_abs_section_ptr)
10283 	def_bfd = hi->root.u.def.section->owner;
10284       _bfd_error_handler (msg, flinfo->output_bfd,
10285 			  h->root.root.string, def_bfd);
10286       bfd_set_error (bfd_error_bad_value);
10287       eoinfo->failed = true;
10288       return false;
10289     }
10290 
10291   /* We don't want to output symbols that have never been mentioned by
10292      a regular file, or that we have been told to strip.  However, if
10293      h->indx is set to -2, the symbol is used by a reloc and we must
10294      output it.  */
10295   strip = false;
10296   if (h->indx == -2)
10297     ;
10298   else if ((h->def_dynamic
10299 	    || h->ref_dynamic
10300 	    || h->root.type == bfd_link_hash_new)
10301 	   && !h->def_regular
10302 	   && !h->ref_regular)
10303     strip = true;
10304   else if (flinfo->info->strip == strip_all)
10305     strip = true;
10306   else if (flinfo->info->strip == strip_some
10307 	   && bfd_hash_lookup (flinfo->info->keep_hash,
10308 			       h->root.root.string, false, false) == NULL)
10309     strip = true;
10310   else if ((h->root.type == bfd_link_hash_defined
10311 	    || h->root.type == bfd_link_hash_defweak)
10312 	   && ((flinfo->info->strip_discarded
10313 		&& discarded_section (h->root.u.def.section))
10314 	       || ((h->root.u.def.section->flags & SEC_LINKER_CREATED) == 0
10315 		   && h->root.u.def.section->owner != NULL
10316 		   && (h->root.u.def.section->owner->flags & BFD_PLUGIN) != 0)))
10317     strip = true;
10318   else if ((h->root.type == bfd_link_hash_undefined
10319 	    || h->root.type == bfd_link_hash_undefweak)
10320 	   && h->root.u.undef.abfd != NULL
10321 	   && (h->root.u.undef.abfd->flags & BFD_PLUGIN) != 0)
10322     strip = true;
10323 
10324   type = h->type;
10325 
10326   /* If we're stripping it, and it's not a dynamic symbol, there's
10327      nothing else to do.   However, if it is a forced local symbol or
10328      an ifunc symbol we need to give the backend finish_dynamic_symbol
10329      function a chance to make it dynamic.  */
10330   if (strip
10331       && h->dynindx == -1
10332       && type != STT_GNU_IFUNC
10333       && !h->forced_local)
10334     return true;
10335 
10336   sym.st_value = 0;
10337   sym.st_size = h->size;
10338   sym.st_other = h->other;
10339   switch (h->root.type)
10340     {
10341     default:
10342     case bfd_link_hash_new:
10343     case bfd_link_hash_warning:
10344       abort ();
10345       return false;
10346 
10347     case bfd_link_hash_undefined:
10348     case bfd_link_hash_undefweak:
10349       input_sec = bfd_und_section_ptr;
10350       sym.st_shndx = SHN_UNDEF;
10351       break;
10352 
10353     case bfd_link_hash_defined:
10354     case bfd_link_hash_defweak:
10355       {
10356 	input_sec = h->root.u.def.section;
10357 	if (input_sec->output_section != NULL)
10358 	  {
10359 	    sym.st_shndx =
10360 	      _bfd_elf_section_from_bfd_section (flinfo->output_bfd,
10361 						 input_sec->output_section);
10362 	    if (sym.st_shndx == SHN_BAD)
10363 	      {
10364 		_bfd_error_handler
10365 		  /* xgettext:c-format */
10366 		  (_("%pB: could not find output section %pA for input section %pA"),
10367 		   flinfo->output_bfd, input_sec->output_section, input_sec);
10368 		bfd_set_error (bfd_error_nonrepresentable_section);
10369 		eoinfo->failed = true;
10370 		return false;
10371 	      }
10372 
10373 	    /* ELF symbols in relocatable files are section relative,
10374 	       but in nonrelocatable files they are virtual
10375 	       addresses.  */
10376 	    sym.st_value = h->root.u.def.value + input_sec->output_offset;
10377 	    if (!bfd_link_relocatable (flinfo->info))
10378 	      {
10379 		sym.st_value += input_sec->output_section->vma;
10380 		if (h->type == STT_TLS)
10381 		  {
10382 		    asection *tls_sec = elf_hash_table (flinfo->info)->tls_sec;
10383 		    if (tls_sec != NULL)
10384 		      sym.st_value -= tls_sec->vma;
10385 		  }
10386 	      }
10387 	  }
10388 	else
10389 	  {
10390 	    BFD_ASSERT (input_sec->owner == NULL
10391 			|| (input_sec->owner->flags & DYNAMIC) != 0);
10392 	    sym.st_shndx = SHN_UNDEF;
10393 	    input_sec = bfd_und_section_ptr;
10394 	  }
10395       }
10396       break;
10397 
10398     case bfd_link_hash_common:
10399       input_sec = h->root.u.c.p->section;
10400       sym.st_shndx = bed->common_section_index (input_sec);
10401       sym.st_value = 1 << h->root.u.c.p->alignment_power;
10402       break;
10403 
10404     case bfd_link_hash_indirect:
10405       /* These symbols are created by symbol versioning.  They point
10406 	 to the decorated version of the name.  For example, if the
10407 	 symbol foo@@GNU_1.2 is the default, which should be used when
10408 	 foo is used with no version, then we add an indirect symbol
10409 	 foo which points to foo@@GNU_1.2.  We ignore these symbols,
10410 	 since the indirected symbol is already in the hash table.  */
10411       return true;
10412     }
10413 
10414   if (type == STT_COMMON || type == STT_OBJECT)
10415     switch (h->root.type)
10416       {
10417       case bfd_link_hash_common:
10418 	type = elf_link_convert_common_type (flinfo->info, type);
10419 	break;
10420       case bfd_link_hash_defined:
10421       case bfd_link_hash_defweak:
10422 	if (bed->common_definition (&sym))
10423 	  type = elf_link_convert_common_type (flinfo->info, type);
10424 	else
10425 	  type = STT_OBJECT;
10426 	break;
10427       case bfd_link_hash_undefined:
10428       case bfd_link_hash_undefweak:
10429 	break;
10430       default:
10431 	abort ();
10432       }
10433 
10434   if (h->forced_local)
10435     {
10436       sym.st_info = ELF_ST_INFO (STB_LOCAL, type);
10437       /* Turn off visibility on local symbol.  */
10438       sym.st_other &= ~ELF_ST_VISIBILITY (-1);
10439     }
10440   /* Set STB_GNU_UNIQUE only if symbol is defined in regular object.  */
10441   else if (h->unique_global && h->def_regular)
10442     sym.st_info = ELF_ST_INFO (STB_GNU_UNIQUE, type);
10443   else if (h->root.type == bfd_link_hash_undefweak
10444 	   || h->root.type == bfd_link_hash_defweak)
10445     sym.st_info = ELF_ST_INFO (STB_WEAK, type);
10446   else
10447     sym.st_info = ELF_ST_INFO (STB_GLOBAL, type);
10448   sym.st_target_internal = h->target_internal;
10449 
10450   /* Give the processor backend a chance to tweak the symbol value,
10451      and also to finish up anything that needs to be done for this
10452      symbol.  FIXME: Not calling elf_backend_finish_dynamic_symbol for
10453      forced local syms when non-shared is due to a historical quirk.
10454      STT_GNU_IFUNC symbol must go through PLT.  */
10455   if ((h->type == STT_GNU_IFUNC
10456        && h->def_regular
10457        && !bfd_link_relocatable (flinfo->info))
10458       || ((h->dynindx != -1
10459 	   || h->forced_local)
10460 	  && ((bfd_link_pic (flinfo->info)
10461 	       && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
10462 		   || h->root.type != bfd_link_hash_undefweak))
10463 	      || !h->forced_local)
10464 	  && elf_hash_table (flinfo->info)->dynamic_sections_created))
10465     {
10466       if (! ((*bed->elf_backend_finish_dynamic_symbol)
10467 	     (flinfo->output_bfd, flinfo->info, h, &sym)))
10468 	{
10469 	  eoinfo->failed = true;
10470 	  return false;
10471 	}
10472     }
10473 
10474   /* If we are marking the symbol as undefined, and there are no
10475      non-weak references to this symbol from a regular object, then
10476      mark the symbol as weak undefined; if there are non-weak
10477      references, mark the symbol as strong.  We can't do this earlier,
10478      because it might not be marked as undefined until the
10479      finish_dynamic_symbol routine gets through with it.  */
10480   if (sym.st_shndx == SHN_UNDEF
10481       && h->ref_regular
10482       && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
10483 	  || ELF_ST_BIND (sym.st_info) == STB_WEAK))
10484     {
10485       int bindtype;
10486       type = ELF_ST_TYPE (sym.st_info);
10487 
10488       /* Turn an undefined IFUNC symbol into a normal FUNC symbol. */
10489       if (type == STT_GNU_IFUNC)
10490 	type = STT_FUNC;
10491 
10492       if (h->ref_regular_nonweak)
10493 	bindtype = STB_GLOBAL;
10494       else
10495 	bindtype = STB_WEAK;
10496       sym.st_info = ELF_ST_INFO (bindtype, type);
10497     }
10498 
10499   /* If this is a symbol defined in a dynamic library, don't use the
10500      symbol size from the dynamic library.  Relinking an executable
10501      against a new library may introduce gratuitous changes in the
10502      executable's symbols if we keep the size.  */
10503   if (sym.st_shndx == SHN_UNDEF
10504       && !h->def_regular
10505       && h->def_dynamic)
10506     sym.st_size = 0;
10507 
10508   /* If a non-weak symbol with non-default visibility is not defined
10509      locally, it is a fatal error.  */
10510   if (!bfd_link_relocatable (flinfo->info)
10511       && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
10512       && ELF_ST_BIND (sym.st_info) != STB_WEAK
10513       && h->root.type == bfd_link_hash_undefined
10514       && !h->def_regular)
10515     {
10516       const char *msg;
10517 
10518       if (ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED)
10519 	/* xgettext:c-format */
10520 	msg = _("%pB: protected symbol `%s' isn't defined");
10521       else if (ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL)
10522 	/* xgettext:c-format */
10523 	msg = _("%pB: internal symbol `%s' isn't defined");
10524       else
10525 	/* xgettext:c-format */
10526 	msg = _("%pB: hidden symbol `%s' isn't defined");
10527       _bfd_error_handler (msg, flinfo->output_bfd, h->root.root.string);
10528       bfd_set_error (bfd_error_bad_value);
10529       eoinfo->failed = true;
10530       return false;
10531     }
10532 
10533   /* If this symbol should be put in the .dynsym section, then put it
10534      there now.  We already know the symbol index.  We also fill in
10535      the entry in the .hash section.  */
10536   if (h->dynindx != -1
10537       && elf_hash_table (flinfo->info)->dynamic_sections_created
10538       && elf_hash_table (flinfo->info)->dynsym != NULL
10539       && !discarded_section (elf_hash_table (flinfo->info)->dynsym))
10540     {
10541       bfd_byte *esym;
10542 
10543       /* Since there is no version information in the dynamic string,
10544 	 if there is no version info in symbol version section, we will
10545 	 have a run-time problem if not linking executable, referenced
10546 	 by shared library, or not bound locally.  */
10547       if (h->verinfo.verdef == NULL
10548 	  && (!bfd_link_executable (flinfo->info)
10549 	      || h->ref_dynamic
10550 	      || !h->def_regular))
10551 	{
10552 	  char *p = strrchr (h->root.root.string, ELF_VER_CHR);
10553 
10554 	  if (p && p [1] != '\0')
10555 	    {
10556 	      _bfd_error_handler
10557 		/* xgettext:c-format */
10558 		(_("%pB: no symbol version section for versioned symbol `%s'"),
10559 		 flinfo->output_bfd, h->root.root.string);
10560 	      eoinfo->failed = true;
10561 	      return false;
10562 	    }
10563 	}
10564 
10565       sym.st_name = h->dynstr_index;
10566       esym = (elf_hash_table (flinfo->info)->dynsym->contents
10567 	      + h->dynindx * bed->s->sizeof_sym);
10568       if (!check_dynsym (flinfo->output_bfd, &sym))
10569 	{
10570 	  eoinfo->failed = true;
10571 	  return false;
10572 	}
10573 
10574       /* Inform the linker of the addition of this symbol.  */
10575 
10576       if (flinfo->info->callbacks->ctf_new_dynsym)
10577 	flinfo->info->callbacks->ctf_new_dynsym (h->dynindx, &sym);
10578 
10579       bed->s->swap_symbol_out (flinfo->output_bfd, &sym, esym, 0);
10580 
10581       if (flinfo->hash_sec != NULL)
10582 	{
10583 	  size_t hash_entry_size;
10584 	  bfd_byte *bucketpos;
10585 	  bfd_vma chain;
10586 	  size_t bucketcount;
10587 	  size_t bucket;
10588 
10589 	  bucketcount = elf_hash_table (flinfo->info)->bucketcount;
10590 	  bucket = h->u.elf_hash_value % bucketcount;
10591 
10592 	  hash_entry_size
10593 	    = elf_section_data (flinfo->hash_sec)->this_hdr.sh_entsize;
10594 	  bucketpos = ((bfd_byte *) flinfo->hash_sec->contents
10595 		       + (bucket + 2) * hash_entry_size);
10596 	  chain = bfd_get (8 * hash_entry_size, flinfo->output_bfd, bucketpos);
10597 	  bfd_put (8 * hash_entry_size, flinfo->output_bfd, h->dynindx,
10598 		   bucketpos);
10599 	  bfd_put (8 * hash_entry_size, flinfo->output_bfd, chain,
10600 		   ((bfd_byte *) flinfo->hash_sec->contents
10601 		    + (bucketcount + 2 + h->dynindx) * hash_entry_size));
10602 	}
10603 
10604       if (flinfo->symver_sec != NULL && flinfo->symver_sec->contents != NULL)
10605 	{
10606 	  Elf_Internal_Versym iversym;
10607 	  Elf_External_Versym *eversym;
10608 
10609 	  if (!h->def_regular && !ELF_COMMON_DEF_P (h))
10610 	    {
10611 	      if (h->verinfo.verdef == NULL
10612 		  || (elf_dyn_lib_class (h->verinfo.verdef->vd_bfd)
10613 		      & (DYN_AS_NEEDED | DYN_DT_NEEDED | DYN_NO_NEEDED)))
10614 		iversym.vs_vers = 1;
10615 	      else
10616 		iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
10617 	    }
10618 	  else
10619 	    {
10620 	      if (h->verinfo.vertree == NULL)
10621 		iversym.vs_vers = 1;
10622 	      else
10623 		iversym.vs_vers = h->verinfo.vertree->vernum + 1;
10624 	      if (flinfo->info->create_default_symver)
10625 		iversym.vs_vers++;
10626 	    }
10627 
10628 	  /* Turn on VERSYM_HIDDEN only if the hidden versioned symbol is
10629 	     defined locally.  */
10630 	  if (h->versioned == versioned_hidden && h->def_regular)
10631 	    iversym.vs_vers |= VERSYM_HIDDEN;
10632 
10633 	  eversym = (Elf_External_Versym *) flinfo->symver_sec->contents;
10634 	  eversym += h->dynindx;
10635 	  _bfd_elf_swap_versym_out (flinfo->output_bfd, &iversym, eversym);
10636 	}
10637     }
10638 
10639   /* If the symbol is undefined, and we didn't output it to .dynsym,
10640      strip it from .symtab too.  Obviously we can't do this for
10641      relocatable output or when needed for --emit-relocs.  */
10642   else if (input_sec == bfd_und_section_ptr
10643 	   && h->indx != -2
10644 	   /* PR 22319 Do not strip global undefined symbols marked as being needed.  */
10645 	   && (h->mark != 1 || ELF_ST_BIND (sym.st_info) != STB_GLOBAL)
10646 	   && !bfd_link_relocatable (flinfo->info))
10647     return true;
10648 
10649   /* Also strip others that we couldn't earlier due to dynamic symbol
10650      processing.  */
10651   if (strip)
10652     return true;
10653   if ((input_sec->flags & SEC_EXCLUDE) != 0)
10654     return true;
10655 
10656   /* Output a FILE symbol so that following locals are not associated
10657      with the wrong input file.  We need one for forced local symbols
10658      if we've seen more than one FILE symbol or when we have exactly
10659      one FILE symbol but global symbols are present in a file other
10660      than the one with the FILE symbol.  We also need one if linker
10661      defined symbols are present.  In practice these conditions are
10662      always met, so just emit the FILE symbol unconditionally.  */
10663   if (eoinfo->localsyms
10664       && !eoinfo->file_sym_done
10665       && eoinfo->flinfo->filesym_count != 0)
10666     {
10667       Elf_Internal_Sym fsym;
10668 
10669       memset (&fsym, 0, sizeof (fsym));
10670       fsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
10671       fsym.st_shndx = SHN_ABS;
10672       if (!elf_link_output_symstrtab (eoinfo->flinfo, NULL, &fsym,
10673 				      bfd_und_section_ptr, NULL))
10674 	return false;
10675 
10676       eoinfo->file_sym_done = true;
10677     }
10678 
10679   indx = bfd_get_symcount (flinfo->output_bfd);
10680   ret = elf_link_output_symstrtab (flinfo, h->root.root.string, &sym,
10681 				   input_sec, h);
10682   if (ret == 0)
10683     {
10684       eoinfo->failed = true;
10685       return false;
10686     }
10687   else if (ret == 1)
10688     h->indx = indx;
10689   else if (h->indx == -2)
10690     abort();
10691 
10692   return true;
10693 }
10694 
10695 /* Return TRUE if special handling is done for relocs in SEC against
10696    symbols defined in discarded sections.  */
10697 
10698 static bool
elf_section_ignore_discarded_relocs(asection * sec)10699 elf_section_ignore_discarded_relocs (asection *sec)
10700 {
10701   const struct elf_backend_data *bed;
10702 
10703   switch (sec->sec_info_type)
10704     {
10705     case SEC_INFO_TYPE_STABS:
10706     case SEC_INFO_TYPE_EH_FRAME:
10707     case SEC_INFO_TYPE_EH_FRAME_ENTRY:
10708       return true;
10709     default:
10710       break;
10711     }
10712 
10713   bed = get_elf_backend_data (sec->owner);
10714   if (bed->elf_backend_ignore_discarded_relocs != NULL
10715       && (*bed->elf_backend_ignore_discarded_relocs) (sec))
10716     return true;
10717 
10718   return false;
10719 }
10720 
10721 /* Return a mask saying how ld should treat relocations in SEC against
10722    symbols defined in discarded sections.  If this function returns
10723    COMPLAIN set, ld will issue a warning message.  If this function
10724    returns PRETEND set, and the discarded section was link-once and the
10725    same size as the kept link-once section, ld will pretend that the
10726    symbol was actually defined in the kept section.  Otherwise ld will
10727    zero the reloc (at least that is the intent, but some cooperation by
10728    the target dependent code is needed, particularly for REL targets).  */
10729 
10730 unsigned int
_bfd_elf_default_action_discarded(asection * sec)10731 _bfd_elf_default_action_discarded (asection *sec)
10732 {
10733   if (sec->flags & SEC_DEBUGGING)
10734     return PRETEND;
10735 
10736   if (strcmp (".eh_frame", sec->name) == 0)
10737     return 0;
10738 
10739   if (strcmp (".gcc_except_table", sec->name) == 0)
10740     return 0;
10741 
10742   return COMPLAIN | PRETEND;
10743 }
10744 
10745 /* Find a match between a section and a member of a section group.  */
10746 
10747 static asection *
match_group_member(asection * sec,asection * group,struct bfd_link_info * info)10748 match_group_member (asection *sec, asection *group,
10749 		    struct bfd_link_info *info)
10750 {
10751   asection *first = elf_next_in_group (group);
10752   asection *s = first;
10753 
10754   while (s != NULL)
10755     {
10756       if (bfd_elf_match_symbols_in_sections (s, sec, info))
10757 	return s;
10758 
10759       s = elf_next_in_group (s);
10760       if (s == first)
10761 	break;
10762     }
10763 
10764   return NULL;
10765 }
10766 
10767 /* Check if the kept section of a discarded section SEC can be used
10768    to replace it.  Return the replacement if it is OK.  Otherwise return
10769    NULL.  */
10770 
10771 asection *
_bfd_elf_check_kept_section(asection * sec,struct bfd_link_info * info)10772 _bfd_elf_check_kept_section (asection *sec, struct bfd_link_info *info)
10773 {
10774   asection *kept;
10775 
10776   kept = sec->kept_section;
10777   if (kept != NULL)
10778     {
10779       if ((kept->flags & SEC_GROUP) != 0)
10780 	kept = match_group_member (sec, kept, info);
10781       if (kept != NULL)
10782 	{
10783 	  if ((sec->rawsize != 0 ? sec->rawsize : sec->size)
10784 	      != (kept->rawsize != 0 ? kept->rawsize : kept->size))
10785 	    kept = NULL;
10786 	  else
10787 	    {
10788 	      /* Get the real kept section.  */
10789 	      asection *next;
10790 	      for (next = kept->kept_section;
10791 		   next != NULL;
10792 		   next = next->kept_section)
10793 		kept = next;
10794 	    }
10795 	}
10796       sec->kept_section = kept;
10797     }
10798   return kept;
10799 }
10800 
10801 /* Link an input file into the linker output file.  This function
10802    handles all the sections and relocations of the input file at once.
10803    This is so that we only have to read the local symbols once, and
10804    don't have to keep them in memory.  */
10805 
10806 static bool
elf_link_input_bfd(struct elf_final_link_info * flinfo,bfd * input_bfd)10807 elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd)
10808 {
10809   int (*relocate_section)
10810     (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
10811      Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
10812   bfd *output_bfd;
10813   Elf_Internal_Shdr *symtab_hdr;
10814   size_t locsymcount;
10815   size_t extsymoff;
10816   Elf_Internal_Sym *isymbuf;
10817   Elf_Internal_Sym *isym;
10818   Elf_Internal_Sym *isymend;
10819   long *pindex;
10820   asection **ppsection;
10821   asection *o;
10822   const struct elf_backend_data *bed;
10823   struct elf_link_hash_entry **sym_hashes;
10824   bfd_size_type address_size;
10825   bfd_vma r_type_mask;
10826   int r_sym_shift;
10827   bool have_file_sym = false;
10828 
10829   output_bfd = flinfo->output_bfd;
10830   bed = get_elf_backend_data (output_bfd);
10831   relocate_section = bed->elf_backend_relocate_section;
10832 
10833   /* If this is a dynamic object, we don't want to do anything here:
10834      we don't want the local symbols, and we don't want the section
10835      contents.  */
10836   if ((input_bfd->flags & DYNAMIC) != 0)
10837     return true;
10838 
10839   symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
10840   if (elf_bad_symtab (input_bfd))
10841     {
10842       locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
10843       extsymoff = 0;
10844     }
10845   else
10846     {
10847       locsymcount = symtab_hdr->sh_info;
10848       extsymoff = symtab_hdr->sh_info;
10849     }
10850 
10851   /* Enable GNU OSABI features in the output BFD that are used in the input
10852      BFD.  */
10853   if (bed->elf_osabi == ELFOSABI_NONE
10854       || bed->elf_osabi == ELFOSABI_GNU
10855       || bed->elf_osabi == ELFOSABI_FREEBSD)
10856     elf_tdata (output_bfd)->has_gnu_osabi
10857       |= (elf_tdata (input_bfd)->has_gnu_osabi
10858 	  & (bfd_link_relocatable (flinfo->info)
10859 	     ? -1 : ~elf_gnu_osabi_retain));
10860 
10861   /* Read the local symbols.  */
10862   isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
10863   if (isymbuf == NULL && locsymcount != 0)
10864     {
10865       isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
10866 				      flinfo->internal_syms,
10867 				      flinfo->external_syms,
10868 				      flinfo->locsym_shndx);
10869       if (isymbuf == NULL)
10870 	return false;
10871     }
10872 
10873   /* Find local symbol sections and adjust values of symbols in
10874      SEC_MERGE sections.  Write out those local symbols we know are
10875      going into the output file.  */
10876   isymend = isymbuf + locsymcount;
10877   for (isym = isymbuf, pindex = flinfo->indices, ppsection = flinfo->sections;
10878        isym < isymend;
10879        isym++, pindex++, ppsection++)
10880     {
10881       asection *isec;
10882       const char *name;
10883       Elf_Internal_Sym osym;
10884       long indx;
10885       int ret;
10886 
10887       *pindex = -1;
10888 
10889       if (elf_bad_symtab (input_bfd))
10890 	{
10891 	  if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
10892 	    {
10893 	      *ppsection = NULL;
10894 	      continue;
10895 	    }
10896 	}
10897 
10898       if (isym->st_shndx == SHN_UNDEF)
10899 	isec = bfd_und_section_ptr;
10900       else if (isym->st_shndx == SHN_ABS)
10901 	isec = bfd_abs_section_ptr;
10902       else if (isym->st_shndx == SHN_COMMON)
10903 	isec = bfd_com_section_ptr;
10904       else
10905 	{
10906 	  isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
10907 	  if (isec == NULL)
10908 	    {
10909 	      /* Don't attempt to output symbols with st_shnx in the
10910 		 reserved range other than SHN_ABS and SHN_COMMON.  */
10911 	      isec = bfd_und_section_ptr;
10912 	    }
10913 	  else if (isec->sec_info_type == SEC_INFO_TYPE_MERGE
10914 		   && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
10915 	    isym->st_value =
10916 	      _bfd_merged_section_offset (output_bfd, &isec,
10917 					  elf_section_data (isec)->sec_info,
10918 					  isym->st_value);
10919 	}
10920 
10921       *ppsection = isec;
10922 
10923       /* Don't output the first, undefined, symbol.  In fact, don't
10924 	 output any undefined local symbol.  */
10925       if (isec == bfd_und_section_ptr)
10926 	continue;
10927 
10928       if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
10929 	{
10930 	  /* We never output section symbols.  Instead, we use the
10931 	     section symbol of the corresponding section in the output
10932 	     file.  */
10933 	  continue;
10934 	}
10935 
10936       /* If we are stripping all symbols, we don't want to output this
10937 	 one.  */
10938       if (flinfo->info->strip == strip_all)
10939 	continue;
10940 
10941       /* If we are discarding all local symbols, we don't want to
10942 	 output this one.  If we are generating a relocatable output
10943 	 file, then some of the local symbols may be required by
10944 	 relocs; we output them below as we discover that they are
10945 	 needed.  */
10946       if (flinfo->info->discard == discard_all)
10947 	continue;
10948 
10949       /* If this symbol is defined in a section which we are
10950 	 discarding, we don't need to keep it.  */
10951       if (isym->st_shndx != SHN_UNDEF
10952 	  && isym->st_shndx < SHN_LORESERVE
10953 	  && isec->output_section == NULL
10954 	  && flinfo->info->non_contiguous_regions
10955 	  && flinfo->info->non_contiguous_regions_warnings)
10956 	{
10957 	  _bfd_error_handler (_("warning: --enable-non-contiguous-regions "
10958 				"discards section `%s' from '%s'\n"),
10959 			      isec->name, bfd_get_filename (isec->owner));
10960 	  continue;
10961 	}
10962 
10963       if (isym->st_shndx != SHN_UNDEF
10964 	  && isym->st_shndx < SHN_LORESERVE
10965 	  && bfd_section_removed_from_list (output_bfd,
10966 					    isec->output_section))
10967 	continue;
10968 
10969       /* Get the name of the symbol.  */
10970       name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
10971 					      isym->st_name);
10972       if (name == NULL)
10973 	return false;
10974 
10975       /* See if we are discarding symbols with this name.  */
10976       if ((flinfo->info->strip == strip_some
10977 	   && (bfd_hash_lookup (flinfo->info->keep_hash, name, false, false)
10978 	       == NULL))
10979 	  || (((flinfo->info->discard == discard_sec_merge
10980 		&& (isec->flags & SEC_MERGE)
10981 		&& !bfd_link_relocatable (flinfo->info))
10982 	       || flinfo->info->discard == discard_l)
10983 	      && bfd_is_local_label_name (input_bfd, name)))
10984 	continue;
10985 
10986       if (ELF_ST_TYPE (isym->st_info) == STT_FILE)
10987 	{
10988 	  if (input_bfd->lto_output)
10989 	    /* -flto puts a temp file name here.  This means builds
10990 	       are not reproducible.  Discard the symbol.  */
10991 	    continue;
10992 	  have_file_sym = true;
10993 	  flinfo->filesym_count += 1;
10994 	}
10995       if (!have_file_sym)
10996 	{
10997 	  /* In the absence of debug info, bfd_find_nearest_line uses
10998 	     FILE symbols to determine the source file for local
10999 	     function symbols.  Provide a FILE symbol here if input
11000 	     files lack such, so that their symbols won't be
11001 	     associated with a previous input file.  It's not the
11002 	     source file, but the best we can do.  */
11003 	  const char *filename;
11004 	  have_file_sym = true;
11005 	  flinfo->filesym_count += 1;
11006 	  memset (&osym, 0, sizeof (osym));
11007 	  osym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE);
11008 	  osym.st_shndx = SHN_ABS;
11009 	  if (input_bfd->lto_output)
11010 	    filename = NULL;
11011 	  else
11012 	    filename = lbasename (bfd_get_filename (input_bfd));
11013 	  if (!elf_link_output_symstrtab (flinfo, filename, &osym,
11014 					  bfd_abs_section_ptr, NULL))
11015 	    return false;
11016 	}
11017 
11018       osym = *isym;
11019 
11020       /* Adjust the section index for the output file.  */
11021       osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
11022 							 isec->output_section);
11023       if (osym.st_shndx == SHN_BAD)
11024 	return false;
11025 
11026       /* ELF symbols in relocatable files are section relative, but
11027 	 in executable files they are virtual addresses.  Note that
11028 	 this code assumes that all ELF sections have an associated
11029 	 BFD section with a reasonable value for output_offset; below
11030 	 we assume that they also have a reasonable value for
11031 	 output_section.  Any special sections must be set up to meet
11032 	 these requirements.  */
11033       osym.st_value += isec->output_offset;
11034       if (!bfd_link_relocatable (flinfo->info))
11035 	{
11036 	  osym.st_value += isec->output_section->vma;
11037 	  if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
11038 	    {
11039 	      /* STT_TLS symbols are relative to PT_TLS segment base.  */
11040 	      if (elf_hash_table (flinfo->info)->tls_sec != NULL)
11041 		osym.st_value -= elf_hash_table (flinfo->info)->tls_sec->vma;
11042 	      else
11043 		osym.st_info = ELF_ST_INFO (ELF_ST_BIND (osym.st_info),
11044 					    STT_NOTYPE);
11045 	    }
11046 	}
11047 
11048       indx = bfd_get_symcount (output_bfd);
11049       ret = elf_link_output_symstrtab (flinfo, name, &osym, isec, NULL);
11050       if (ret == 0)
11051 	return false;
11052       else if (ret == 1)
11053 	*pindex = indx;
11054     }
11055 
11056   if (bed->s->arch_size == 32)
11057     {
11058       r_type_mask = 0xff;
11059       r_sym_shift = 8;
11060       address_size = 4;
11061     }
11062   else
11063     {
11064       r_type_mask = 0xffffffff;
11065       r_sym_shift = 32;
11066       address_size = 8;
11067     }
11068 
11069   /* Relocate the contents of each section.  */
11070   sym_hashes = elf_sym_hashes (input_bfd);
11071   for (o = input_bfd->sections; o != NULL; o = o->next)
11072     {
11073       bfd_byte *contents;
11074 
11075       if (! o->linker_mark)
11076 	{
11077 	  /* This section was omitted from the link.  */
11078 	  continue;
11079 	}
11080 
11081       if (!flinfo->info->resolve_section_groups
11082 	  && (o->flags & (SEC_LINKER_CREATED | SEC_GROUP)) == SEC_GROUP)
11083 	{
11084 	  /* Deal with the group signature symbol.  */
11085 	  struct bfd_elf_section_data *sec_data = elf_section_data (o);
11086 	  unsigned long symndx = sec_data->this_hdr.sh_info;
11087 	  asection *osec = o->output_section;
11088 
11089 	  BFD_ASSERT (bfd_link_relocatable (flinfo->info));
11090 	  if (symndx >= locsymcount
11091 	      || (elf_bad_symtab (input_bfd)
11092 		  && flinfo->sections[symndx] == NULL))
11093 	    {
11094 	      struct elf_link_hash_entry *h = sym_hashes[symndx - extsymoff];
11095 	      while (h->root.type == bfd_link_hash_indirect
11096 		     || h->root.type == bfd_link_hash_warning)
11097 		h = (struct elf_link_hash_entry *) h->root.u.i.link;
11098 	      /* Arrange for symbol to be output.  */
11099 	      h->indx = -2;
11100 	      elf_section_data (osec)->this_hdr.sh_info = -2;
11101 	    }
11102 	  else if (ELF_ST_TYPE (isymbuf[symndx].st_info) == STT_SECTION)
11103 	    {
11104 	      /* We'll use the output section target_index.  */
11105 	      asection *sec = flinfo->sections[symndx]->output_section;
11106 	      elf_section_data (osec)->this_hdr.sh_info = sec->target_index;
11107 	    }
11108 	  else
11109 	    {
11110 	      if (flinfo->indices[symndx] == -1)
11111 		{
11112 		  /* Otherwise output the local symbol now.  */
11113 		  Elf_Internal_Sym sym = isymbuf[symndx];
11114 		  asection *sec = flinfo->sections[symndx]->output_section;
11115 		  const char *name;
11116 		  long indx;
11117 		  int ret;
11118 
11119 		  name = bfd_elf_string_from_elf_section (input_bfd,
11120 							  symtab_hdr->sh_link,
11121 							  sym.st_name);
11122 		  if (name == NULL)
11123 		    return false;
11124 
11125 		  sym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
11126 								    sec);
11127 		  if (sym.st_shndx == SHN_BAD)
11128 		    return false;
11129 
11130 		  sym.st_value += o->output_offset;
11131 
11132 		  indx = bfd_get_symcount (output_bfd);
11133 		  ret = elf_link_output_symstrtab (flinfo, name, &sym, o,
11134 						   NULL);
11135 		  if (ret == 0)
11136 		    return false;
11137 		  else if (ret == 1)
11138 		    flinfo->indices[symndx] = indx;
11139 		  else
11140 		    abort ();
11141 		}
11142 	      elf_section_data (osec)->this_hdr.sh_info
11143 		= flinfo->indices[symndx];
11144 	    }
11145 	}
11146 
11147       if ((o->flags & SEC_HAS_CONTENTS) == 0
11148 	  || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
11149 	continue;
11150 
11151       if ((o->flags & SEC_LINKER_CREATED) != 0)
11152 	{
11153 	  /* Section was created by _bfd_elf_link_create_dynamic_sections
11154 	     or somesuch.  */
11155 	  continue;
11156 	}
11157 
11158       /* Get the contents of the section.  They have been cached by a
11159 	 relaxation routine.  Note that o is a section in an input
11160 	 file, so the contents field will not have been set by any of
11161 	 the routines which work on output files.  */
11162       if (elf_section_data (o)->this_hdr.contents != NULL)
11163 	{
11164 	  contents = elf_section_data (o)->this_hdr.contents;
11165 	  if (bed->caches_rawsize
11166 	      && o->rawsize != 0
11167 	      && o->rawsize < o->size)
11168 	    {
11169 	      memcpy (flinfo->contents, contents, o->rawsize);
11170 	      contents = flinfo->contents;
11171 	    }
11172 	}
11173       else
11174 	{
11175 	  contents = flinfo->contents;
11176 	  if (! bfd_get_full_section_contents (input_bfd, o, &contents))
11177 	    return false;
11178 	}
11179 
11180       if ((o->flags & SEC_RELOC) != 0)
11181 	{
11182 	  Elf_Internal_Rela *internal_relocs;
11183 	  Elf_Internal_Rela *rel, *relend;
11184 	  int action_discarded;
11185 	  int ret;
11186 
11187 	  /* Get the swapped relocs.  */
11188 	  internal_relocs
11189 	    = _bfd_elf_link_read_relocs (input_bfd, o, flinfo->external_relocs,
11190 					 flinfo->internal_relocs, false);
11191 	  if (internal_relocs == NULL
11192 	      && o->reloc_count > 0)
11193 	    return false;
11194 
11195 	  /* We need to reverse-copy input .ctors/.dtors sections if
11196 	     they are placed in .init_array/.finit_array for output.  */
11197 	  if (o->size > address_size
11198 	      && ((startswith (o->name, ".ctors")
11199 		   && strcmp (o->output_section->name,
11200 			      ".init_array") == 0)
11201 		  || (startswith (o->name, ".dtors")
11202 		      && strcmp (o->output_section->name,
11203 				 ".fini_array") == 0))
11204 	      && (o->name[6] == 0 || o->name[6] == '.'))
11205 	    {
11206 	      if (o->size * bed->s->int_rels_per_ext_rel
11207 		  != o->reloc_count * address_size)
11208 		{
11209 		  _bfd_error_handler
11210 		    /* xgettext:c-format */
11211 		    (_("error: %pB: size of section %pA is not "
11212 		       "multiple of address size"),
11213 		     input_bfd, o);
11214 		  bfd_set_error (bfd_error_bad_value);
11215 		  return false;
11216 		}
11217 	      o->flags |= SEC_ELF_REVERSE_COPY;
11218 	    }
11219 
11220 	  action_discarded = -1;
11221 	  if (!elf_section_ignore_discarded_relocs (o))
11222 	    action_discarded = (*bed->action_discarded) (o);
11223 
11224 	  /* Run through the relocs evaluating complex reloc symbols and
11225 	     looking for relocs against symbols from discarded sections
11226 	     or section symbols from removed link-once sections.
11227 	     Complain about relocs against discarded sections.  Zero
11228 	     relocs against removed link-once sections.  */
11229 
11230 	  rel = internal_relocs;
11231 	  relend = rel + o->reloc_count;
11232 	  for ( ; rel < relend; rel++)
11233 	    {
11234 	      unsigned long r_symndx = rel->r_info >> r_sym_shift;
11235 	      unsigned int s_type;
11236 	      asection **ps, *sec;
11237 	      struct elf_link_hash_entry *h = NULL;
11238 	      const char *sym_name;
11239 
11240 	      if (r_symndx == STN_UNDEF)
11241 		continue;
11242 
11243 	      if (r_symndx >= locsymcount
11244 		  || (elf_bad_symtab (input_bfd)
11245 		      && flinfo->sections[r_symndx] == NULL))
11246 		{
11247 		  h = sym_hashes[r_symndx - extsymoff];
11248 
11249 		  /* Badly formatted input files can contain relocs that
11250 		     reference non-existant symbols.  Check here so that
11251 		     we do not seg fault.  */
11252 		  if (h == NULL)
11253 		    {
11254 		      _bfd_error_handler
11255 			/* xgettext:c-format */
11256 			(_("error: %pB contains a reloc (%#" PRIx64 ") for section %pA "
11257 			   "that references a non-existent global symbol"),
11258 			 input_bfd, (uint64_t) rel->r_info, o);
11259 		      bfd_set_error (bfd_error_bad_value);
11260 		      return false;
11261 		    }
11262 
11263 		  while (h->root.type == bfd_link_hash_indirect
11264 			 || h->root.type == bfd_link_hash_warning)
11265 		    h = (struct elf_link_hash_entry *) h->root.u.i.link;
11266 
11267 		  s_type = h->type;
11268 
11269 		  /* If a plugin symbol is referenced from a non-IR file,
11270 		     mark the symbol as undefined.  Note that the
11271 		     linker may attach linker created dynamic sections
11272 		     to the plugin bfd.  Symbols defined in linker
11273 		     created sections are not plugin symbols.  */
11274 		  if ((h->root.non_ir_ref_regular
11275 		       || h->root.non_ir_ref_dynamic)
11276 		      && (h->root.type == bfd_link_hash_defined
11277 			  || h->root.type == bfd_link_hash_defweak)
11278 		      && (h->root.u.def.section->flags
11279 			  & SEC_LINKER_CREATED) == 0
11280 		      && h->root.u.def.section->owner != NULL
11281 		      && (h->root.u.def.section->owner->flags
11282 			  & BFD_PLUGIN) != 0)
11283 		    {
11284 		      h->root.type = bfd_link_hash_undefined;
11285 		      h->root.u.undef.abfd = h->root.u.def.section->owner;
11286 		    }
11287 
11288 		  ps = NULL;
11289 		  if (h->root.type == bfd_link_hash_defined
11290 		      || h->root.type == bfd_link_hash_defweak)
11291 		    ps = &h->root.u.def.section;
11292 
11293 		  sym_name = h->root.root.string;
11294 		}
11295 	      else
11296 		{
11297 		  Elf_Internal_Sym *sym = isymbuf + r_symndx;
11298 
11299 		  s_type = ELF_ST_TYPE (sym->st_info);
11300 		  ps = &flinfo->sections[r_symndx];
11301 		  sym_name = bfd_elf_sym_name (input_bfd, symtab_hdr,
11302 					       sym, *ps);
11303 		}
11304 
11305 	      if ((s_type == STT_RELC || s_type == STT_SRELC)
11306 		  && !bfd_link_relocatable (flinfo->info))
11307 		{
11308 		  bfd_vma val;
11309 		  bfd_vma dot = (rel->r_offset
11310 				 + o->output_offset + o->output_section->vma);
11311 #ifdef DEBUG
11312 		  printf ("Encountered a complex symbol!");
11313 		  printf (" (input_bfd %s, section %s, reloc %ld\n",
11314 			  bfd_get_filename (input_bfd), o->name,
11315 			  (long) (rel - internal_relocs));
11316 		  printf (" symbol: idx  %8.8lx, name %s\n",
11317 			  r_symndx, sym_name);
11318 		  printf (" reloc : info %8.8lx, addr %8.8lx\n",
11319 			  (unsigned long) rel->r_info,
11320 			  (unsigned long) rel->r_offset);
11321 #endif
11322 		  if (!eval_symbol (&val, &sym_name, input_bfd, flinfo, dot,
11323 				    isymbuf, locsymcount, s_type == STT_SRELC))
11324 		    return false;
11325 
11326 		  /* Symbol evaluated OK.  Update to absolute value.  */
11327 		  set_symbol_value (input_bfd, isymbuf, locsymcount,
11328 				    r_symndx, val);
11329 		  continue;
11330 		}
11331 
11332 	      if (action_discarded != -1 && ps != NULL)
11333 		{
11334 		  /* Complain if the definition comes from a
11335 		     discarded section.  */
11336 		  if ((sec = *ps) != NULL && discarded_section (sec))
11337 		    {
11338 		      BFD_ASSERT (r_symndx != STN_UNDEF);
11339 		      if (action_discarded & COMPLAIN)
11340 			(*flinfo->info->callbacks->einfo)
11341 			  /* xgettext:c-format */
11342 			  (_("%X`%s' referenced in section `%pA' of %pB: "
11343 			     "defined in discarded section `%pA' of %pB\n"),
11344 			   sym_name, o, input_bfd, sec, sec->owner);
11345 
11346 		      /* Try to do the best we can to support buggy old
11347 			 versions of gcc.  Pretend that the symbol is
11348 			 really defined in the kept linkonce section.
11349 			 FIXME: This is quite broken.  Modifying the
11350 			 symbol here means we will be changing all later
11351 			 uses of the symbol, not just in this section.  */
11352 		      if (action_discarded & PRETEND)
11353 			{
11354 			  asection *kept;
11355 
11356 			  kept = _bfd_elf_check_kept_section (sec,
11357 							      flinfo->info);
11358 			  if (kept != NULL)
11359 			    {
11360 			      *ps = kept;
11361 			      continue;
11362 			    }
11363 			}
11364 		    }
11365 		}
11366 	    }
11367 
11368 	  /* Relocate the section by invoking a back end routine.
11369 
11370 	     The back end routine is responsible for adjusting the
11371 	     section contents as necessary, and (if using Rela relocs
11372 	     and generating a relocatable output file) adjusting the
11373 	     reloc addend as necessary.
11374 
11375 	     The back end routine does not have to worry about setting
11376 	     the reloc address or the reloc symbol index.
11377 
11378 	     The back end routine is given a pointer to the swapped in
11379 	     internal symbols, and can access the hash table entries
11380 	     for the external symbols via elf_sym_hashes (input_bfd).
11381 
11382 	     When generating relocatable output, the back end routine
11383 	     must handle STB_LOCAL/STT_SECTION symbols specially.  The
11384 	     output symbol is going to be a section symbol
11385 	     corresponding to the output section, which will require
11386 	     the addend to be adjusted.  */
11387 
11388 	  ret = (*relocate_section) (output_bfd, flinfo->info,
11389 				     input_bfd, o, contents,
11390 				     internal_relocs,
11391 				     isymbuf,
11392 				     flinfo->sections);
11393 	  if (!ret)
11394 	    return false;
11395 
11396 	  if (ret == 2
11397 	      || bfd_link_relocatable (flinfo->info)
11398 	      || flinfo->info->emitrelocations)
11399 	    {
11400 	      Elf_Internal_Rela *irela;
11401 	      Elf_Internal_Rela *irelaend, *irelamid;
11402 	      bfd_vma last_offset;
11403 	      struct elf_link_hash_entry **rel_hash;
11404 	      struct elf_link_hash_entry **rel_hash_list, **rela_hash_list;
11405 	      Elf_Internal_Shdr *input_rel_hdr, *input_rela_hdr;
11406 	      unsigned int next_erel;
11407 	      bool rela_normal;
11408 	      struct bfd_elf_section_data *esdi, *esdo;
11409 
11410 	      esdi = elf_section_data (o);
11411 	      esdo = elf_section_data (o->output_section);
11412 	      rela_normal = false;
11413 
11414 	      /* Adjust the reloc addresses and symbol indices.  */
11415 
11416 	      irela = internal_relocs;
11417 	      irelaend = irela + o->reloc_count;
11418 	      rel_hash = esdo->rel.hashes + esdo->rel.count;
11419 	      /* We start processing the REL relocs, if any.  When we reach
11420 		 IRELAMID in the loop, we switch to the RELA relocs.  */
11421 	      irelamid = irela;
11422 	      if (esdi->rel.hdr != NULL)
11423 		irelamid += (NUM_SHDR_ENTRIES (esdi->rel.hdr)
11424 			     * bed->s->int_rels_per_ext_rel);
11425 	      rel_hash_list = rel_hash;
11426 	      rela_hash_list = NULL;
11427 	      last_offset = o->output_offset;
11428 	      if (!bfd_link_relocatable (flinfo->info))
11429 		last_offset += o->output_section->vma;
11430 	      for (next_erel = 0; irela < irelaend; irela++, next_erel++)
11431 		{
11432 		  unsigned long r_symndx;
11433 		  asection *sec;
11434 		  Elf_Internal_Sym sym;
11435 
11436 		  if (next_erel == bed->s->int_rels_per_ext_rel)
11437 		    {
11438 		      rel_hash++;
11439 		      next_erel = 0;
11440 		    }
11441 
11442 		  if (irela == irelamid)
11443 		    {
11444 		      rel_hash = esdo->rela.hashes + esdo->rela.count;
11445 		      rela_hash_list = rel_hash;
11446 		      rela_normal = bed->rela_normal;
11447 		    }
11448 
11449 		  irela->r_offset = _bfd_elf_section_offset (output_bfd,
11450 							     flinfo->info, o,
11451 							     irela->r_offset);
11452 		  if (irela->r_offset >= (bfd_vma) -2)
11453 		    {
11454 		      /* This is a reloc for a deleted entry or somesuch.
11455 			 Turn it into an R_*_NONE reloc, at the same
11456 			 offset as the last reloc.  elf_eh_frame.c and
11457 			 bfd_elf_discard_info rely on reloc offsets
11458 			 being ordered.  */
11459 		      irela->r_offset = last_offset;
11460 		      irela->r_info = 0;
11461 		      irela->r_addend = 0;
11462 		      continue;
11463 		    }
11464 
11465 		  irela->r_offset += o->output_offset;
11466 
11467 		  /* Relocs in an executable have to be virtual addresses.  */
11468 		  if (!bfd_link_relocatable (flinfo->info))
11469 		    irela->r_offset += o->output_section->vma;
11470 
11471 		  last_offset = irela->r_offset;
11472 
11473 		  r_symndx = irela->r_info >> r_sym_shift;
11474 		  if (r_symndx == STN_UNDEF)
11475 		    continue;
11476 
11477 		  if (r_symndx >= locsymcount
11478 		      || (elf_bad_symtab (input_bfd)
11479 			  && flinfo->sections[r_symndx] == NULL))
11480 		    {
11481 		      struct elf_link_hash_entry *rh;
11482 		      unsigned long indx;
11483 
11484 		      /* This is a reloc against a global symbol.  We
11485 			 have not yet output all the local symbols, so
11486 			 we do not know the symbol index of any global
11487 			 symbol.  We set the rel_hash entry for this
11488 			 reloc to point to the global hash table entry
11489 			 for this symbol.  The symbol index is then
11490 			 set at the end of bfd_elf_final_link.  */
11491 		      indx = r_symndx - extsymoff;
11492 		      rh = elf_sym_hashes (input_bfd)[indx];
11493 		      while (rh->root.type == bfd_link_hash_indirect
11494 			     || rh->root.type == bfd_link_hash_warning)
11495 			rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
11496 
11497 		      /* Setting the index to -2 tells
11498 			 elf_link_output_extsym that this symbol is
11499 			 used by a reloc.  */
11500 		      BFD_ASSERT (rh->indx < 0);
11501 		      rh->indx = -2;
11502 		      *rel_hash = rh;
11503 
11504 		      continue;
11505 		    }
11506 
11507 		  /* This is a reloc against a local symbol.  */
11508 
11509 		  *rel_hash = NULL;
11510 		  sym = isymbuf[r_symndx];
11511 		  sec = flinfo->sections[r_symndx];
11512 		  if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
11513 		    {
11514 		      /* I suppose the backend ought to fill in the
11515 			 section of any STT_SECTION symbol against a
11516 			 processor specific section.  */
11517 		      r_symndx = STN_UNDEF;
11518 		      if (bfd_is_abs_section (sec))
11519 			;
11520 		      else if (sec == NULL || sec->owner == NULL)
11521 			{
11522 			  bfd_set_error (bfd_error_bad_value);
11523 			  return false;
11524 			}
11525 		      else
11526 			{
11527 			  asection *osec = sec->output_section;
11528 
11529 			  /* If we have discarded a section, the output
11530 			     section will be the absolute section.  In
11531 			     case of discarded SEC_MERGE sections, use
11532 			     the kept section.  relocate_section should
11533 			     have already handled discarded linkonce
11534 			     sections.  */
11535 			  if (bfd_is_abs_section (osec)
11536 			      && sec->kept_section != NULL
11537 			      && sec->kept_section->output_section != NULL)
11538 			    {
11539 			      osec = sec->kept_section->output_section;
11540 			      irela->r_addend -= osec->vma;
11541 			    }
11542 
11543 			  if (!bfd_is_abs_section (osec))
11544 			    {
11545 			      r_symndx = osec->target_index;
11546 			      if (r_symndx == STN_UNDEF)
11547 				{
11548 				  irela->r_addend += osec->vma;
11549 				  osec = _bfd_nearby_section (output_bfd, osec,
11550 							      osec->vma);
11551 				  irela->r_addend -= osec->vma;
11552 				  r_symndx = osec->target_index;
11553 				}
11554 			    }
11555 			}
11556 
11557 		      /* Adjust the addend according to where the
11558 			 section winds up in the output section.  */
11559 		      if (rela_normal)
11560 			irela->r_addend += sec->output_offset;
11561 		    }
11562 		  else
11563 		    {
11564 		      if (flinfo->indices[r_symndx] == -1)
11565 			{
11566 			  unsigned long shlink;
11567 			  const char *name;
11568 			  asection *osec;
11569 			  long indx;
11570 
11571 			  if (flinfo->info->strip == strip_all)
11572 			    {
11573 			      /* You can't do ld -r -s.  */
11574 			      bfd_set_error (bfd_error_invalid_operation);
11575 			      return false;
11576 			    }
11577 
11578 			  /* This symbol was skipped earlier, but
11579 			     since it is needed by a reloc, we
11580 			     must output it now.  */
11581 			  shlink = symtab_hdr->sh_link;
11582 			  name = (bfd_elf_string_from_elf_section
11583 				  (input_bfd, shlink, sym.st_name));
11584 			  if (name == NULL)
11585 			    return false;
11586 
11587 			  osec = sec->output_section;
11588 			  sym.st_shndx =
11589 			    _bfd_elf_section_from_bfd_section (output_bfd,
11590 							       osec);
11591 			  if (sym.st_shndx == SHN_BAD)
11592 			    return false;
11593 
11594 			  sym.st_value += sec->output_offset;
11595 			  if (!bfd_link_relocatable (flinfo->info))
11596 			    {
11597 			      sym.st_value += osec->vma;
11598 			      if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
11599 				{
11600 				  struct elf_link_hash_table *htab
11601 				    = elf_hash_table (flinfo->info);
11602 
11603 				  /* STT_TLS symbols are relative to PT_TLS
11604 				     segment base.  */
11605 				  if (htab->tls_sec != NULL)
11606 				    sym.st_value -= htab->tls_sec->vma;
11607 				  else
11608 				    sym.st_info
11609 				      = ELF_ST_INFO (ELF_ST_BIND (sym.st_info),
11610 						     STT_NOTYPE);
11611 				}
11612 			    }
11613 
11614 			  indx = bfd_get_symcount (output_bfd);
11615 			  ret = elf_link_output_symstrtab (flinfo, name,
11616 							   &sym, sec,
11617 							   NULL);
11618 			  if (ret == 0)
11619 			    return false;
11620 			  else if (ret == 1)
11621 			    flinfo->indices[r_symndx] = indx;
11622 			  else
11623 			    abort ();
11624 			}
11625 
11626 		      r_symndx = flinfo->indices[r_symndx];
11627 		    }
11628 
11629 		  irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
11630 				   | (irela->r_info & r_type_mask));
11631 		}
11632 
11633 	      /* Swap out the relocs.  */
11634 	      input_rel_hdr = esdi->rel.hdr;
11635 	      if (input_rel_hdr && input_rel_hdr->sh_size != 0)
11636 		{
11637 		  if (!bed->elf_backend_emit_relocs (output_bfd, o,
11638 						     input_rel_hdr,
11639 						     internal_relocs,
11640 						     rel_hash_list))
11641 		    return false;
11642 		  internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
11643 				      * bed->s->int_rels_per_ext_rel);
11644 		  rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
11645 		}
11646 
11647 	      input_rela_hdr = esdi->rela.hdr;
11648 	      if (input_rela_hdr && input_rela_hdr->sh_size != 0)
11649 		{
11650 		  if (!bed->elf_backend_emit_relocs (output_bfd, o,
11651 						     input_rela_hdr,
11652 						     internal_relocs,
11653 						     rela_hash_list))
11654 		    return false;
11655 		}
11656 	    }
11657 	}
11658 
11659       /* Write out the modified section contents.  */
11660       if (bed->elf_backend_write_section
11661 	  && (*bed->elf_backend_write_section) (output_bfd, flinfo->info, o,
11662 						contents))
11663 	{
11664 	  /* Section written out.  */
11665 	}
11666       else switch (o->sec_info_type)
11667 	{
11668 	case SEC_INFO_TYPE_STABS:
11669 	  if (! (_bfd_write_section_stabs
11670 		 (output_bfd,
11671 		  &elf_hash_table (flinfo->info)->stab_info,
11672 		  o, &elf_section_data (o)->sec_info, contents)))
11673 	    return false;
11674 	  break;
11675 	case SEC_INFO_TYPE_MERGE:
11676 	  if (! _bfd_write_merged_section (output_bfd, o,
11677 					   elf_section_data (o)->sec_info))
11678 	    return false;
11679 	  break;
11680 	case SEC_INFO_TYPE_EH_FRAME:
11681 	  {
11682 	    if (! _bfd_elf_write_section_eh_frame (output_bfd, flinfo->info,
11683 						   o, contents))
11684 	      return false;
11685 	  }
11686 	  break;
11687 	case SEC_INFO_TYPE_EH_FRAME_ENTRY:
11688 	  {
11689 	    if (! _bfd_elf_write_section_eh_frame_entry (output_bfd,
11690 							 flinfo->info,
11691 							 o, contents))
11692 	      return false;
11693 	  }
11694 	  break;
11695 	default:
11696 	  {
11697 	    if (! (o->flags & SEC_EXCLUDE))
11698 	      {
11699 		file_ptr offset = (file_ptr) o->output_offset;
11700 		bfd_size_type todo = o->size;
11701 
11702 		offset *= bfd_octets_per_byte (output_bfd, o);
11703 
11704 		if ((o->flags & SEC_ELF_REVERSE_COPY))
11705 		  {
11706 		    /* Reverse-copy input section to output.  */
11707 		    do
11708 		      {
11709 			todo -= address_size;
11710 			if (! bfd_set_section_contents (output_bfd,
11711 							o->output_section,
11712 							contents + todo,
11713 							offset,
11714 							address_size))
11715 			  return false;
11716 			if (todo == 0)
11717 			  break;
11718 			offset += address_size;
11719 		      }
11720 		    while (1);
11721 		  }
11722 		else if (! bfd_set_section_contents (output_bfd,
11723 						     o->output_section,
11724 						     contents,
11725 						     offset, todo))
11726 		  return false;
11727 	      }
11728 	  }
11729 	  break;
11730 	}
11731     }
11732 
11733   return true;
11734 }
11735 
11736 /* Generate a reloc when linking an ELF file.  This is a reloc
11737    requested by the linker, and does not come from any input file.  This
11738    is used to build constructor and destructor tables when linking
11739    with -Ur.  */
11740 
11741 static bool
elf_reloc_link_order(bfd * output_bfd,struct bfd_link_info * info,asection * output_section,struct bfd_link_order * link_order)11742 elf_reloc_link_order (bfd *output_bfd,
11743 		      struct bfd_link_info *info,
11744 		      asection *output_section,
11745 		      struct bfd_link_order *link_order)
11746 {
11747   reloc_howto_type *howto;
11748   long indx;
11749   bfd_vma offset;
11750   bfd_vma addend;
11751   struct bfd_elf_section_reloc_data *reldata;
11752   struct elf_link_hash_entry **rel_hash_ptr;
11753   Elf_Internal_Shdr *rel_hdr;
11754   const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
11755   Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
11756   bfd_byte *erel;
11757   unsigned int i;
11758   struct bfd_elf_section_data *esdo = elf_section_data (output_section);
11759 
11760   howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
11761   if (howto == NULL)
11762     {
11763       bfd_set_error (bfd_error_bad_value);
11764       return false;
11765     }
11766 
11767   addend = link_order->u.reloc.p->addend;
11768 
11769   if (esdo->rel.hdr)
11770     reldata = &esdo->rel;
11771   else if (esdo->rela.hdr)
11772     reldata = &esdo->rela;
11773   else
11774     {
11775       reldata = NULL;
11776       BFD_ASSERT (0);
11777     }
11778 
11779   /* Figure out the symbol index.  */
11780   rel_hash_ptr = reldata->hashes + reldata->count;
11781   if (link_order->type == bfd_section_reloc_link_order)
11782     {
11783       indx = link_order->u.reloc.p->u.section->target_index;
11784       BFD_ASSERT (indx != 0);
11785       *rel_hash_ptr = NULL;
11786     }
11787   else
11788     {
11789       struct elf_link_hash_entry *h;
11790 
11791       /* Treat a reloc against a defined symbol as though it were
11792 	 actually against the section.  */
11793       h = ((struct elf_link_hash_entry *)
11794 	   bfd_wrapped_link_hash_lookup (output_bfd, info,
11795 					 link_order->u.reloc.p->u.name,
11796 					 false, false, true));
11797       if (h != NULL
11798 	  && (h->root.type == bfd_link_hash_defined
11799 	      || h->root.type == bfd_link_hash_defweak))
11800 	{
11801 	  asection *section;
11802 
11803 	  section = h->root.u.def.section;
11804 	  indx = section->output_section->target_index;
11805 	  *rel_hash_ptr = NULL;
11806 	  /* It seems that we ought to add the symbol value to the
11807 	     addend here, but in practice it has already been added
11808 	     because it was passed to constructor_callback.  */
11809 	  addend += section->output_section->vma + section->output_offset;
11810 	}
11811       else if (h != NULL)
11812 	{
11813 	  /* Setting the index to -2 tells elf_link_output_extsym that
11814 	     this symbol is used by a reloc.  */
11815 	  h->indx = -2;
11816 	  *rel_hash_ptr = h;
11817 	  indx = 0;
11818 	}
11819       else
11820 	{
11821 	  (*info->callbacks->unattached_reloc)
11822 	    (info, link_order->u.reloc.p->u.name, NULL, NULL, 0);
11823 	  indx = 0;
11824 	}
11825     }
11826 
11827   /* If this is an inplace reloc, we must write the addend into the
11828      object file.  */
11829   if (howto->partial_inplace && addend != 0)
11830     {
11831       bfd_size_type size;
11832       bfd_reloc_status_type rstat;
11833       bfd_byte *buf;
11834       bool ok;
11835       const char *sym_name;
11836       bfd_size_type octets;
11837 
11838       size = (bfd_size_type) bfd_get_reloc_size (howto);
11839       buf = (bfd_byte *) bfd_zmalloc (size);
11840       if (buf == NULL && size != 0)
11841 	return false;
11842       rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
11843       switch (rstat)
11844 	{
11845 	case bfd_reloc_ok:
11846 	  break;
11847 
11848 	default:
11849 	case bfd_reloc_outofrange:
11850 	  abort ();
11851 
11852 	case bfd_reloc_overflow:
11853 	  if (link_order->type == bfd_section_reloc_link_order)
11854 	    sym_name = bfd_section_name (link_order->u.reloc.p->u.section);
11855 	  else
11856 	    sym_name = link_order->u.reloc.p->u.name;
11857 	  (*info->callbacks->reloc_overflow) (info, NULL, sym_name,
11858 					      howto->name, addend, NULL, NULL,
11859 					      (bfd_vma) 0);
11860 	  break;
11861 	}
11862 
11863       octets = link_order->offset * bfd_octets_per_byte (output_bfd,
11864 							 output_section);
11865       ok = bfd_set_section_contents (output_bfd, output_section, buf,
11866 				     octets, size);
11867       free (buf);
11868       if (! ok)
11869 	return false;
11870     }
11871 
11872   /* The address of a reloc is relative to the section in a
11873      relocatable file, and is a virtual address in an executable
11874      file.  */
11875   offset = link_order->offset;
11876   if (! bfd_link_relocatable (info))
11877     offset += output_section->vma;
11878 
11879   for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
11880     {
11881       irel[i].r_offset = offset;
11882       irel[i].r_info = 0;
11883       irel[i].r_addend = 0;
11884     }
11885   if (bed->s->arch_size == 32)
11886     irel[0].r_info = ELF32_R_INFO (indx, howto->type);
11887   else
11888     irel[0].r_info = ELF64_R_INFO (indx, howto->type);
11889 
11890   rel_hdr = reldata->hdr;
11891   erel = rel_hdr->contents;
11892   if (rel_hdr->sh_type == SHT_REL)
11893     {
11894       erel += reldata->count * bed->s->sizeof_rel;
11895       (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
11896     }
11897   else
11898     {
11899       irel[0].r_addend = addend;
11900       erel += reldata->count * bed->s->sizeof_rela;
11901       (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
11902     }
11903 
11904   ++reldata->count;
11905 
11906   return true;
11907 }
11908 
11909 /* Generate an import library in INFO->implib_bfd from symbols in ABFD.
11910    Returns TRUE upon success, FALSE otherwise.  */
11911 
11912 static bool
elf_output_implib(bfd * abfd,struct bfd_link_info * info)11913 elf_output_implib (bfd *abfd, struct bfd_link_info *info)
11914 {
11915   bool ret = false;
11916   bfd *implib_bfd;
11917   const struct elf_backend_data *bed;
11918   flagword flags;
11919   enum bfd_architecture arch;
11920   unsigned int mach;
11921   asymbol **sympp = NULL;
11922   long symsize;
11923   long symcount;
11924   long src_count;
11925   elf_symbol_type *osymbuf;
11926   size_t amt;
11927 
11928   implib_bfd = info->out_implib_bfd;
11929   bed = get_elf_backend_data (abfd);
11930 
11931   if (!bfd_set_format (implib_bfd, bfd_object))
11932     return false;
11933 
11934   /* Use flag from executable but make it a relocatable object.  */
11935   flags = bfd_get_file_flags (abfd);
11936   flags &= ~HAS_RELOC;
11937   if (!bfd_set_start_address (implib_bfd, 0)
11938       || !bfd_set_file_flags (implib_bfd, flags & ~EXEC_P))
11939     return false;
11940 
11941   /* Copy architecture of output file to import library file.  */
11942   arch = bfd_get_arch (abfd);
11943   mach = bfd_get_mach (abfd);
11944   if (!bfd_set_arch_mach (implib_bfd, arch, mach)
11945       && (abfd->target_defaulted
11946 	  || bfd_get_arch (abfd) != bfd_get_arch (implib_bfd)))
11947     return false;
11948 
11949   /* Get symbol table size.  */
11950   symsize = bfd_get_symtab_upper_bound (abfd);
11951   if (symsize < 0)
11952     return false;
11953 
11954   /* Read in the symbol table.  */
11955   sympp = (asymbol **) bfd_malloc (symsize);
11956   if (sympp == NULL)
11957     return false;
11958 
11959   symcount = bfd_canonicalize_symtab (abfd, sympp);
11960   if (symcount < 0)
11961     goto free_sym_buf;
11962 
11963   /* Allow the BFD backend to copy any private header data it
11964      understands from the output BFD to the import library BFD.  */
11965   if (! bfd_copy_private_header_data (abfd, implib_bfd))
11966     goto free_sym_buf;
11967 
11968   /* Filter symbols to appear in the import library.  */
11969   if (bed->elf_backend_filter_implib_symbols)
11970     symcount = bed->elf_backend_filter_implib_symbols (abfd, info, sympp,
11971 						       symcount);
11972   else
11973     symcount = _bfd_elf_filter_global_symbols (abfd, info, sympp, symcount);
11974   if (symcount == 0)
11975     {
11976       bfd_set_error (bfd_error_no_symbols);
11977       _bfd_error_handler (_("%pB: no symbol found for import library"),
11978 			  implib_bfd);
11979       goto free_sym_buf;
11980     }
11981 
11982 
11983   /* Make symbols absolute.  */
11984   amt = symcount * sizeof (*osymbuf);
11985   osymbuf = (elf_symbol_type *) bfd_alloc (implib_bfd, amt);
11986   if (osymbuf == NULL)
11987     goto free_sym_buf;
11988 
11989   for (src_count = 0; src_count < symcount; src_count++)
11990     {
11991       memcpy (&osymbuf[src_count], (elf_symbol_type *) sympp[src_count],
11992 	      sizeof (*osymbuf));
11993       osymbuf[src_count].symbol.section = bfd_abs_section_ptr;
11994       osymbuf[src_count].internal_elf_sym.st_shndx = SHN_ABS;
11995       osymbuf[src_count].symbol.value += sympp[src_count]->section->vma;
11996       osymbuf[src_count].internal_elf_sym.st_value =
11997 	osymbuf[src_count].symbol.value;
11998       sympp[src_count] = &osymbuf[src_count].symbol;
11999     }
12000 
12001   bfd_set_symtab (implib_bfd, sympp, symcount);
12002 
12003   /* Allow the BFD backend to copy any private data it understands
12004      from the output BFD to the import library BFD.  This is done last
12005      to permit the routine to look at the filtered symbol table.  */
12006   if (! bfd_copy_private_bfd_data (abfd, implib_bfd))
12007     goto free_sym_buf;
12008 
12009   if (!bfd_close (implib_bfd))
12010     goto free_sym_buf;
12011 
12012   ret = true;
12013 
12014  free_sym_buf:
12015   free (sympp);
12016   return ret;
12017 }
12018 
12019 static void
elf_final_link_free(bfd * obfd,struct elf_final_link_info * flinfo)12020 elf_final_link_free (bfd *obfd, struct elf_final_link_info *flinfo)
12021 {
12022   asection *o;
12023 
12024   if (flinfo->symstrtab != NULL)
12025     _bfd_elf_strtab_free (flinfo->symstrtab);
12026   free (flinfo->contents);
12027   free (flinfo->external_relocs);
12028   free (flinfo->internal_relocs);
12029   free (flinfo->external_syms);
12030   free (flinfo->locsym_shndx);
12031   free (flinfo->internal_syms);
12032   free (flinfo->indices);
12033   free (flinfo->sections);
12034   if (flinfo->symshndxbuf != (Elf_External_Sym_Shndx *) -1)
12035     free (flinfo->symshndxbuf);
12036   for (o = obfd->sections; o != NULL; o = o->next)
12037     {
12038       struct bfd_elf_section_data *esdo = elf_section_data (o);
12039       free (esdo->rel.hashes);
12040       free (esdo->rela.hashes);
12041     }
12042 }
12043 
12044 /* Do the final step of an ELF link.  */
12045 
12046 bool
bfd_elf_final_link(bfd * abfd,struct bfd_link_info * info)12047 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
12048 {
12049   bool dynamic;
12050   bool emit_relocs;
12051   bfd *dynobj;
12052   struct elf_final_link_info flinfo;
12053   asection *o;
12054   struct bfd_link_order *p;
12055   bfd *sub;
12056   bfd_size_type max_contents_size;
12057   bfd_size_type max_external_reloc_size;
12058   bfd_size_type max_internal_reloc_count;
12059   bfd_size_type max_sym_count;
12060   bfd_size_type max_sym_shndx_count;
12061   Elf_Internal_Sym elfsym;
12062   unsigned int i;
12063   Elf_Internal_Shdr *symtab_hdr;
12064   Elf_Internal_Shdr *symtab_shndx_hdr;
12065   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
12066   struct elf_outext_info eoinfo;
12067   bool merged;
12068   size_t relativecount = 0;
12069   asection *reldyn = 0;
12070   bfd_size_type amt;
12071   asection *attr_section = NULL;
12072   bfd_vma attr_size = 0;
12073   const char *std_attrs_section;
12074   struct elf_link_hash_table *htab = elf_hash_table (info);
12075   bool sections_removed;
12076   bool ret;
12077 
12078   if (!is_elf_hash_table (&htab->root))
12079     return false;
12080 
12081   if (bfd_link_pic (info))
12082     abfd->flags |= DYNAMIC;
12083 
12084   dynamic = htab->dynamic_sections_created;
12085   dynobj = htab->dynobj;
12086 
12087   emit_relocs = (bfd_link_relocatable (info)
12088 		 || info->emitrelocations);
12089 
12090   memset (&flinfo, 0, sizeof (flinfo));
12091   flinfo.info = info;
12092   flinfo.output_bfd = abfd;
12093   flinfo.symstrtab = _bfd_elf_strtab_init ();
12094   if (flinfo.symstrtab == NULL)
12095     return false;
12096 
12097   if (! dynamic)
12098     {
12099       flinfo.hash_sec = NULL;
12100       flinfo.symver_sec = NULL;
12101     }
12102   else
12103     {
12104       flinfo.hash_sec = bfd_get_linker_section (dynobj, ".hash");
12105       /* Note that dynsym_sec can be NULL (on VMS).  */
12106       flinfo.symver_sec = bfd_get_linker_section (dynobj, ".gnu.version");
12107       /* Note that it is OK if symver_sec is NULL.  */
12108     }
12109 
12110   if (info->unique_symbol
12111       && !bfd_hash_table_init (&flinfo.local_hash_table,
12112 			       local_hash_newfunc,
12113 			       sizeof (struct local_hash_entry)))
12114     return false;
12115 
12116   /* The object attributes have been merged.  Remove the input
12117      sections from the link, and set the contents of the output
12118      section.  */
12119   sections_removed = false;
12120   std_attrs_section = get_elf_backend_data (abfd)->obj_attrs_section;
12121   for (o = abfd->sections; o != NULL; o = o->next)
12122     {
12123       bool remove_section = false;
12124 
12125       if ((std_attrs_section && strcmp (o->name, std_attrs_section) == 0)
12126 	  || strcmp (o->name, ".gnu.attributes") == 0)
12127 	{
12128 	  for (p = o->map_head.link_order; p != NULL; p = p->next)
12129 	    {
12130 	      asection *input_section;
12131 
12132 	      if (p->type != bfd_indirect_link_order)
12133 		continue;
12134 	      input_section = p->u.indirect.section;
12135 	      /* Hack: reset the SEC_HAS_CONTENTS flag so that
12136 		 elf_link_input_bfd ignores this section.  */
12137 	      input_section->flags &= ~SEC_HAS_CONTENTS;
12138 	    }
12139 
12140 	  attr_size = bfd_elf_obj_attr_size (abfd);
12141 	  bfd_set_section_size (o, attr_size);
12142 	  /* Skip this section later on.  */
12143 	  o->map_head.link_order = NULL;
12144 	  if (attr_size)
12145 	    attr_section = o;
12146 	  else
12147 	    remove_section = true;
12148 	}
12149       else if ((o->flags & SEC_GROUP) != 0 && o->size == 0)
12150 	{
12151 	  /* Remove empty group section from linker output.  */
12152 	  remove_section = true;
12153 	}
12154       if (remove_section)
12155 	{
12156 	  o->flags |= SEC_EXCLUDE;
12157 	  bfd_section_list_remove (abfd, o);
12158 	  abfd->section_count--;
12159 	  sections_removed = true;
12160 	}
12161     }
12162   if (sections_removed)
12163     _bfd_fix_excluded_sec_syms (abfd, info);
12164 
12165   /* Count up the number of relocations we will output for each output
12166      section, so that we know the sizes of the reloc sections.  We
12167      also figure out some maximum sizes.  */
12168   max_contents_size = 0;
12169   max_external_reloc_size = 0;
12170   max_internal_reloc_count = 0;
12171   max_sym_count = 0;
12172   max_sym_shndx_count = 0;
12173   merged = false;
12174   for (o = abfd->sections; o != NULL; o = o->next)
12175     {
12176       struct bfd_elf_section_data *esdo = elf_section_data (o);
12177       o->reloc_count = 0;
12178 
12179       for (p = o->map_head.link_order; p != NULL; p = p->next)
12180 	{
12181 	  unsigned int reloc_count = 0;
12182 	  unsigned int additional_reloc_count = 0;
12183 	  struct bfd_elf_section_data *esdi = NULL;
12184 
12185 	  if (p->type == bfd_section_reloc_link_order
12186 	      || p->type == bfd_symbol_reloc_link_order)
12187 	    reloc_count = 1;
12188 	  else if (p->type == bfd_indirect_link_order)
12189 	    {
12190 	      asection *sec;
12191 
12192 	      sec = p->u.indirect.section;
12193 
12194 	      /* Mark all sections which are to be included in the
12195 		 link.  This will normally be every section.  We need
12196 		 to do this so that we can identify any sections which
12197 		 the linker has decided to not include.  */
12198 	      sec->linker_mark = true;
12199 
12200 	      if (sec->flags & SEC_MERGE)
12201 		merged = true;
12202 
12203 	      if (sec->rawsize > max_contents_size)
12204 		max_contents_size = sec->rawsize;
12205 	      if (sec->size > max_contents_size)
12206 		max_contents_size = sec->size;
12207 
12208 	      if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
12209 		  && (sec->owner->flags & DYNAMIC) == 0)
12210 		{
12211 		  size_t sym_count;
12212 
12213 		  /* We are interested in just local symbols, not all
12214 		     symbols.  */
12215 		  if (elf_bad_symtab (sec->owner))
12216 		    sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
12217 				 / bed->s->sizeof_sym);
12218 		  else
12219 		    sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
12220 
12221 		  if (sym_count > max_sym_count)
12222 		    max_sym_count = sym_count;
12223 
12224 		  if (sym_count > max_sym_shndx_count
12225 		      && elf_symtab_shndx_list (sec->owner) != NULL)
12226 		    max_sym_shndx_count = sym_count;
12227 
12228 		  if (esdo->this_hdr.sh_type == SHT_REL
12229 		      || esdo->this_hdr.sh_type == SHT_RELA)
12230 		    /* Some backends use reloc_count in relocation sections
12231 		       to count particular types of relocs.  Of course,
12232 		       reloc sections themselves can't have relocations.  */
12233 		    ;
12234 		  else if (emit_relocs)
12235 		    {
12236 		      reloc_count = sec->reloc_count;
12237 		      if (bed->elf_backend_count_additional_relocs)
12238 			{
12239 			  int c;
12240 			  c = (*bed->elf_backend_count_additional_relocs) (sec);
12241 			  additional_reloc_count += c;
12242 			}
12243 		    }
12244 		  else if (bed->elf_backend_count_relocs)
12245 		    reloc_count = (*bed->elf_backend_count_relocs) (info, sec);
12246 
12247 		  esdi = elf_section_data (sec);
12248 
12249 		  if ((sec->flags & SEC_RELOC) != 0)
12250 		    {
12251 		      size_t ext_size = 0;
12252 
12253 		      if (esdi->rel.hdr != NULL)
12254 			ext_size = esdi->rel.hdr->sh_size;
12255 		      if (esdi->rela.hdr != NULL)
12256 			ext_size += esdi->rela.hdr->sh_size;
12257 
12258 		      if (ext_size > max_external_reloc_size)
12259 			max_external_reloc_size = ext_size;
12260 		      if (sec->reloc_count > max_internal_reloc_count)
12261 			max_internal_reloc_count = sec->reloc_count;
12262 		    }
12263 		}
12264 	    }
12265 
12266 	  if (reloc_count == 0)
12267 	    continue;
12268 
12269 	  reloc_count += additional_reloc_count;
12270 	  o->reloc_count += reloc_count;
12271 
12272 	  if (p->type == bfd_indirect_link_order && emit_relocs)
12273 	    {
12274 	      if (esdi->rel.hdr)
12275 		{
12276 		  esdo->rel.count += NUM_SHDR_ENTRIES (esdi->rel.hdr);
12277 		  esdo->rel.count += additional_reloc_count;
12278 		}
12279 	      if (esdi->rela.hdr)
12280 		{
12281 		  esdo->rela.count += NUM_SHDR_ENTRIES (esdi->rela.hdr);
12282 		  esdo->rela.count += additional_reloc_count;
12283 		}
12284 	    }
12285 	  else
12286 	    {
12287 	      if (o->use_rela_p)
12288 		esdo->rela.count += reloc_count;
12289 	      else
12290 		esdo->rel.count += reloc_count;
12291 	    }
12292 	}
12293 
12294       if (o->reloc_count > 0)
12295 	o->flags |= SEC_RELOC;
12296       else
12297 	{
12298 	  /* Explicitly clear the SEC_RELOC flag.  The linker tends to
12299 	     set it (this is probably a bug) and if it is set
12300 	     assign_section_numbers will create a reloc section.  */
12301 	  o->flags &=~ SEC_RELOC;
12302 	}
12303 
12304       /* If the SEC_ALLOC flag is not set, force the section VMA to
12305 	 zero.  This is done in elf_fake_sections as well, but forcing
12306 	 the VMA to 0 here will ensure that relocs against these
12307 	 sections are handled correctly.  */
12308       if ((o->flags & SEC_ALLOC) == 0
12309 	  && ! o->user_set_vma)
12310 	o->vma = 0;
12311     }
12312 
12313   if (! bfd_link_relocatable (info) && merged)
12314     elf_link_hash_traverse (htab, _bfd_elf_link_sec_merge_syms, abfd);
12315 
12316   /* Figure out the file positions for everything but the symbol table
12317      and the relocs.  We set symcount to force assign_section_numbers
12318      to create a symbol table.  */
12319   abfd->symcount = info->strip != strip_all || emit_relocs;
12320   BFD_ASSERT (! abfd->output_has_begun);
12321   if (! _bfd_elf_compute_section_file_positions (abfd, info))
12322     goto error_return;
12323 
12324   /* Set sizes, and assign file positions for reloc sections.  */
12325   for (o = abfd->sections; o != NULL; o = o->next)
12326     {
12327       struct bfd_elf_section_data *esdo = elf_section_data (o);
12328       if ((o->flags & SEC_RELOC) != 0)
12329 	{
12330 	  if (esdo->rel.hdr
12331 	      && !(_bfd_elf_link_size_reloc_section (abfd, &esdo->rel)))
12332 	    goto error_return;
12333 
12334 	  if (esdo->rela.hdr
12335 	      && !(_bfd_elf_link_size_reloc_section (abfd, &esdo->rela)))
12336 	    goto error_return;
12337 	}
12338 
12339       /* _bfd_elf_compute_section_file_positions makes temporary use
12340 	 of target_index.  Reset it.  */
12341       o->target_index = 0;
12342 
12343       /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
12344 	 to count upwards while actually outputting the relocations.  */
12345       esdo->rel.count = 0;
12346       esdo->rela.count = 0;
12347 
12348       if ((esdo->this_hdr.sh_offset == (file_ptr) -1)
12349 	  && !bfd_section_is_ctf (o))
12350 	{
12351 	  /* Cache the section contents so that they can be compressed
12352 	     later.  Use bfd_malloc since it will be freed by
12353 	     bfd_compress_section_contents.  */
12354 	  unsigned char *contents = esdo->this_hdr.contents;
12355 	  if ((o->flags & SEC_ELF_COMPRESS) == 0 || contents != NULL)
12356 	    abort ();
12357 	  contents
12358 	    = (unsigned char *) bfd_malloc (esdo->this_hdr.sh_size);
12359 	  if (contents == NULL)
12360 	    goto error_return;
12361 	  esdo->this_hdr.contents = contents;
12362 	}
12363     }
12364 
12365   /* We have now assigned file positions for all the sections except .symtab,
12366      .strtab, and non-loaded reloc and compressed debugging sections.  We start
12367      the .symtab section at the current file position, and write directly to it.
12368      We build the .strtab section in memory.  */
12369   abfd->symcount = 0;
12370   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
12371   /* sh_name is set in prep_headers.  */
12372   symtab_hdr->sh_type = SHT_SYMTAB;
12373   /* sh_flags, sh_addr and sh_size all start off zero.  */
12374   symtab_hdr->sh_entsize = bed->s->sizeof_sym;
12375   /* sh_link is set in assign_section_numbers.  */
12376   /* sh_info is set below.  */
12377   /* sh_offset is set just below.  */
12378   symtab_hdr->sh_addralign = (bfd_vma) 1 << bed->s->log_file_align;
12379 
12380   if (max_sym_count < 20)
12381     max_sym_count = 20;
12382   htab->strtabsize = max_sym_count;
12383   amt = max_sym_count * sizeof (struct elf_sym_strtab);
12384   htab->strtab = (struct elf_sym_strtab *) bfd_malloc (amt);
12385   if (htab->strtab == NULL)
12386     goto error_return;
12387   /* The real buffer will be allocated in elf_link_swap_symbols_out.  */
12388   flinfo.symshndxbuf
12389     = (elf_numsections (abfd) > (SHN_LORESERVE & 0xFFFF)
12390        ? (Elf_External_Sym_Shndx *) -1 : NULL);
12391 
12392   if (info->strip != strip_all || emit_relocs)
12393     {
12394       file_ptr off = elf_next_file_pos (abfd);
12395 
12396       _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true);
12397 
12398       /* Note that at this point elf_next_file_pos (abfd) is
12399 	 incorrect.  We do not yet know the size of the .symtab section.
12400 	 We correct next_file_pos below, after we do know the size.  */
12401 
12402       /* Start writing out the symbol table.  The first symbol is always a
12403 	 dummy symbol.  */
12404       elfsym.st_value = 0;
12405       elfsym.st_size = 0;
12406       elfsym.st_info = 0;
12407       elfsym.st_other = 0;
12408       elfsym.st_shndx = SHN_UNDEF;
12409       elfsym.st_target_internal = 0;
12410       if (elf_link_output_symstrtab (&flinfo, NULL, &elfsym,
12411 				     bfd_und_section_ptr, NULL) != 1)
12412 	goto error_return;
12413 
12414       /* Output a symbol for each section if asked or they are used for
12415 	 relocs.  These symbols usually have no names.  We store the
12416 	 index of each one in the index field of the section, so that
12417 	 we can find it again when outputting relocs.  */
12418 
12419       if (bfd_keep_unused_section_symbols (abfd) || emit_relocs)
12420 	{
12421 	  bool name_local_sections
12422 	    = (bed->elf_backend_name_local_section_symbols
12423 	       && bed->elf_backend_name_local_section_symbols (abfd));
12424 	  const char *name = NULL;
12425 
12426 	  elfsym.st_size = 0;
12427 	  elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
12428 	  elfsym.st_other = 0;
12429 	  elfsym.st_value = 0;
12430 	  elfsym.st_target_internal = 0;
12431 	  for (i = 1; i < elf_numsections (abfd); i++)
12432 	    {
12433 	      o = bfd_section_from_elf_index (abfd, i);
12434 	      if (o != NULL)
12435 		{
12436 		  o->target_index = bfd_get_symcount (abfd);
12437 		  elfsym.st_shndx = i;
12438 		  if (!bfd_link_relocatable (info))
12439 		    elfsym.st_value = o->vma;
12440 		  if (name_local_sections)
12441 		    name = o->name;
12442 		  if (elf_link_output_symstrtab (&flinfo, name, &elfsym, o,
12443 						 NULL) != 1)
12444 		    goto error_return;
12445 		}
12446 	    }
12447 	}
12448     }
12449 
12450   /* On some targets like Irix 5 the symbol split between local and global
12451      ones recorded in the sh_info field needs to be done between section
12452      and all other symbols.  */
12453   if (bed->elf_backend_elfsym_local_is_section
12454       && bed->elf_backend_elfsym_local_is_section (abfd))
12455     symtab_hdr->sh_info = bfd_get_symcount (abfd);
12456 
12457   /* Allocate some memory to hold information read in from the input
12458      files.  */
12459   if (max_contents_size != 0)
12460     {
12461       flinfo.contents = (bfd_byte *) bfd_malloc (max_contents_size);
12462       if (flinfo.contents == NULL)
12463 	goto error_return;
12464     }
12465 
12466   if (max_external_reloc_size != 0)
12467     {
12468       flinfo.external_relocs = bfd_malloc (max_external_reloc_size);
12469       if (flinfo.external_relocs == NULL)
12470 	goto error_return;
12471     }
12472 
12473   if (max_internal_reloc_count != 0)
12474     {
12475       amt = max_internal_reloc_count * sizeof (Elf_Internal_Rela);
12476       flinfo.internal_relocs = (Elf_Internal_Rela *) bfd_malloc (amt);
12477       if (flinfo.internal_relocs == NULL)
12478 	goto error_return;
12479     }
12480 
12481   if (max_sym_count != 0)
12482     {
12483       amt = max_sym_count * bed->s->sizeof_sym;
12484       flinfo.external_syms = (bfd_byte *) bfd_malloc (amt);
12485       if (flinfo.external_syms == NULL)
12486 	goto error_return;
12487 
12488       amt = max_sym_count * sizeof (Elf_Internal_Sym);
12489       flinfo.internal_syms = (Elf_Internal_Sym *) bfd_malloc (amt);
12490       if (flinfo.internal_syms == NULL)
12491 	goto error_return;
12492 
12493       amt = max_sym_count * sizeof (long);
12494       flinfo.indices = (long int *) bfd_malloc (amt);
12495       if (flinfo.indices == NULL)
12496 	goto error_return;
12497 
12498       amt = max_sym_count * sizeof (asection *);
12499       flinfo.sections = (asection **) bfd_malloc (amt);
12500       if (flinfo.sections == NULL)
12501 	goto error_return;
12502     }
12503 
12504   if (max_sym_shndx_count != 0)
12505     {
12506       amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
12507       flinfo.locsym_shndx = (Elf_External_Sym_Shndx *) bfd_malloc (amt);
12508       if (flinfo.locsym_shndx == NULL)
12509 	goto error_return;
12510     }
12511 
12512   if (htab->tls_sec)
12513     {
12514       bfd_vma base, end = 0;  /* Both bytes.  */
12515       asection *sec;
12516 
12517       for (sec = htab->tls_sec;
12518 	   sec && (sec->flags & SEC_THREAD_LOCAL);
12519 	   sec = sec->next)
12520 	{
12521 	  bfd_size_type size = sec->size;
12522 	  unsigned int opb = bfd_octets_per_byte (abfd, sec);
12523 
12524 	  if (size == 0
12525 	      && (sec->flags & SEC_HAS_CONTENTS) == 0)
12526 	    {
12527 	      struct bfd_link_order *ord = sec->map_tail.link_order;
12528 
12529 	      if (ord != NULL)
12530 		size = ord->offset * opb + ord->size;
12531 	    }
12532 	  end = sec->vma + size / opb;
12533 	}
12534       base = htab->tls_sec->vma;
12535       /* Only align end of TLS section if static TLS doesn't have special
12536 	 alignment requirements.  */
12537       if (bed->static_tls_alignment == 1)
12538 	end = align_power (end, htab->tls_sec->alignment_power);
12539       htab->tls_size = end - base;
12540     }
12541 
12542   if (!_bfd_elf_fixup_eh_frame_hdr (info))
12543     return false;
12544 
12545   /* Since ELF permits relocations to be against local symbols, we
12546      must have the local symbols available when we do the relocations.
12547      Since we would rather only read the local symbols once, and we
12548      would rather not keep them in memory, we handle all the
12549      relocations for a single input file at the same time.
12550 
12551      Unfortunately, there is no way to know the total number of local
12552      symbols until we have seen all of them, and the local symbol
12553      indices precede the global symbol indices.  This means that when
12554      we are generating relocatable output, and we see a reloc against
12555      a global symbol, we can not know the symbol index until we have
12556      finished examining all the local symbols to see which ones we are
12557      going to output.  To deal with this, we keep the relocations in
12558      memory, and don't output them until the end of the link.  This is
12559      an unfortunate waste of memory, but I don't see a good way around
12560      it.  Fortunately, it only happens when performing a relocatable
12561      link, which is not the common case.  FIXME: If keep_memory is set
12562      we could write the relocs out and then read them again; I don't
12563      know how bad the memory loss will be.  */
12564 
12565   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
12566     sub->output_has_begun = false;
12567   for (o = abfd->sections; o != NULL; o = o->next)
12568     {
12569       for (p = o->map_head.link_order; p != NULL; p = p->next)
12570 	{
12571 	  if (p->type == bfd_indirect_link_order
12572 	      && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
12573 		  == bfd_target_elf_flavour)
12574 	      && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
12575 	    {
12576 	      if (! sub->output_has_begun)
12577 		{
12578 		  if (! elf_link_input_bfd (&flinfo, sub))
12579 		    goto error_return;
12580 		  sub->output_has_begun = true;
12581 		}
12582 	    }
12583 	  else if (p->type == bfd_section_reloc_link_order
12584 		   || p->type == bfd_symbol_reloc_link_order)
12585 	    {
12586 	      if (! elf_reloc_link_order (abfd, info, o, p))
12587 		goto error_return;
12588 	    }
12589 	  else
12590 	    {
12591 	      if (! _bfd_default_link_order (abfd, info, o, p))
12592 		{
12593 		  if (p->type == bfd_indirect_link_order
12594 		      && (bfd_get_flavour (sub)
12595 			  == bfd_target_elf_flavour)
12596 		      && (elf_elfheader (sub)->e_ident[EI_CLASS]
12597 			  != bed->s->elfclass))
12598 		    {
12599 		      const char *iclass, *oclass;
12600 
12601 		      switch (bed->s->elfclass)
12602 			{
12603 			case ELFCLASS64: oclass = "ELFCLASS64"; break;
12604 			case ELFCLASS32: oclass = "ELFCLASS32"; break;
12605 			case ELFCLASSNONE: oclass = "ELFCLASSNONE"; break;
12606 			default: abort ();
12607 			}
12608 
12609 		      switch (elf_elfheader (sub)->e_ident[EI_CLASS])
12610 			{
12611 			case ELFCLASS64: iclass = "ELFCLASS64"; break;
12612 			case ELFCLASS32: iclass = "ELFCLASS32"; break;
12613 			case ELFCLASSNONE: iclass = "ELFCLASSNONE"; break;
12614 			default: abort ();
12615 			}
12616 
12617 		      bfd_set_error (bfd_error_wrong_format);
12618 		      _bfd_error_handler
12619 			/* xgettext:c-format */
12620 			(_("%pB: file class %s incompatible with %s"),
12621 			 sub, iclass, oclass);
12622 		    }
12623 
12624 		  goto error_return;
12625 		}
12626 	    }
12627 	}
12628     }
12629 
12630   /* Free symbol buffer if needed.  */
12631   if (!info->reduce_memory_overheads)
12632     {
12633       for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
12634 	if (bfd_get_flavour (sub) == bfd_target_elf_flavour)
12635 	  {
12636 	    free (elf_tdata (sub)->symbuf);
12637 	    elf_tdata (sub)->symbuf = NULL;
12638 	  }
12639     }
12640 
12641   ret = true;
12642 
12643   /* Output any global symbols that got converted to local in a
12644      version script or due to symbol visibility.  We do this in a
12645      separate step since ELF requires all local symbols to appear
12646      prior to any global symbols.  FIXME: We should only do this if
12647      some global symbols were, in fact, converted to become local.
12648      FIXME: Will this work correctly with the Irix 5 linker?  */
12649   eoinfo.failed = false;
12650   eoinfo.flinfo = &flinfo;
12651   eoinfo.localsyms = true;
12652   eoinfo.file_sym_done = false;
12653   bfd_hash_traverse (&info->hash->table, elf_link_output_extsym, &eoinfo);
12654   if (eoinfo.failed)
12655     {
12656       ret = false;
12657       goto return_local_hash_table;
12658     }
12659 
12660   /* If backend needs to output some local symbols not present in the hash
12661      table, do it now.  */
12662   if (bed->elf_backend_output_arch_local_syms
12663       && (info->strip != strip_all || emit_relocs))
12664     {
12665       if (! ((*bed->elf_backend_output_arch_local_syms)
12666 	     (abfd, info, &flinfo, elf_link_output_symstrtab)))
12667 	{
12668 	  ret = false;
12669 	  goto return_local_hash_table;
12670 	}
12671     }
12672 
12673   /* That wrote out all the local symbols.  Finish up the symbol table
12674      with the global symbols. Even if we want to strip everything we
12675      can, we still need to deal with those global symbols that got
12676      converted to local in a version script.  */
12677 
12678   /* The sh_info field records the index of the first non local symbol.  */
12679   if (!symtab_hdr->sh_info)
12680     symtab_hdr->sh_info = bfd_get_symcount (abfd);
12681 
12682   if (dynamic
12683       && htab->dynsym != NULL
12684       && htab->dynsym->output_section != bfd_abs_section_ptr)
12685     {
12686       Elf_Internal_Sym sym;
12687       bfd_byte *dynsym = htab->dynsym->contents;
12688 
12689       o = htab->dynsym->output_section;
12690       elf_section_data (o)->this_hdr.sh_info = htab->local_dynsymcount + 1;
12691 
12692       /* Write out the section symbols for the output sections.  */
12693       if (bfd_link_pic (info)
12694 	  || htab->is_relocatable_executable)
12695 	{
12696 	  asection *s;
12697 
12698 	  sym.st_size = 0;
12699 	  sym.st_name = 0;
12700 	  sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
12701 	  sym.st_other = 0;
12702 	  sym.st_target_internal = 0;
12703 
12704 	  for (s = abfd->sections; s != NULL; s = s->next)
12705 	    {
12706 	      int indx;
12707 	      bfd_byte *dest;
12708 	      long dynindx;
12709 
12710 	      dynindx = elf_section_data (s)->dynindx;
12711 	      if (dynindx <= 0)
12712 		continue;
12713 	      indx = elf_section_data (s)->this_idx;
12714 	      BFD_ASSERT (indx > 0);
12715 	      sym.st_shndx = indx;
12716 	      if (! check_dynsym (abfd, &sym))
12717 		{
12718 		  ret = false;
12719 		  goto return_local_hash_table;
12720 		}
12721 	      sym.st_value = s->vma;
12722 	      dest = dynsym + dynindx * bed->s->sizeof_sym;
12723 
12724 	      /* Inform the linker of the addition of this symbol.  */
12725 
12726 	      if (info->callbacks->ctf_new_dynsym)
12727 		info->callbacks->ctf_new_dynsym (dynindx, &sym);
12728 
12729 	      bed->s->swap_symbol_out (abfd, &sym, dest, 0);
12730 	    }
12731 	}
12732 
12733       /* Write out the local dynsyms.  */
12734       if (htab->dynlocal)
12735 	{
12736 	  struct elf_link_local_dynamic_entry *e;
12737 	  for (e = htab->dynlocal; e ; e = e->next)
12738 	    {
12739 	      asection *s;
12740 	      bfd_byte *dest;
12741 
12742 	      /* Copy the internal symbol and turn off visibility.
12743 		 Note that we saved a word of storage and overwrote
12744 		 the original st_name with the dynstr_index.  */
12745 	      sym = e->isym;
12746 	      sym.st_other &= ~ELF_ST_VISIBILITY (-1);
12747 	      sym.st_shndx = SHN_UNDEF;
12748 
12749 	      s = bfd_section_from_elf_index (e->input_bfd,
12750 					      e->isym.st_shndx);
12751 	      if (s != NULL
12752 		  && s->output_section != NULL
12753 		  && elf_section_data (s->output_section) != NULL)
12754 		{
12755 		  sym.st_shndx =
12756 		    elf_section_data (s->output_section)->this_idx;
12757 		  if (! check_dynsym (abfd, &sym))
12758 		    {
12759 		      ret = false;
12760 		      goto return_local_hash_table;
12761 		    }
12762 		  sym.st_value = (s->output_section->vma
12763 				  + s->output_offset
12764 				  + e->isym.st_value);
12765 		}
12766 
12767 	      /* Inform the linker of the addition of this symbol.  */
12768 
12769 	      if (info->callbacks->ctf_new_dynsym)
12770 		info->callbacks->ctf_new_dynsym (e->dynindx, &sym);
12771 
12772 	      dest = dynsym + e->dynindx * bed->s->sizeof_sym;
12773 	      bed->s->swap_symbol_out (abfd, &sym, dest, 0);
12774 	    }
12775 	}
12776     }
12777 
12778   /* We get the global symbols from the hash table.  */
12779   eoinfo.failed = false;
12780   eoinfo.localsyms = false;
12781   eoinfo.flinfo = &flinfo;
12782   bfd_hash_traverse (&info->hash->table, elf_link_output_extsym, &eoinfo);
12783   if (eoinfo.failed)
12784     {
12785       ret = false;
12786       goto return_local_hash_table;
12787     }
12788 
12789   /* If backend needs to output some symbols not present in the hash
12790      table, do it now.  */
12791   if (bed->elf_backend_output_arch_syms
12792       && (info->strip != strip_all || emit_relocs))
12793     {
12794       if (! ((*bed->elf_backend_output_arch_syms)
12795 	     (abfd, info, &flinfo, elf_link_output_symstrtab)))
12796 	{
12797 	  ret = false;
12798 	  goto return_local_hash_table;
12799 	}
12800     }
12801 
12802   /* Finalize the .strtab section.  */
12803   _bfd_elf_strtab_finalize (flinfo.symstrtab);
12804 
12805   /* Swap out the .strtab section. */
12806   if (!elf_link_swap_symbols_out (&flinfo))
12807     {
12808       ret = false;
12809       goto return_local_hash_table;
12810     }
12811 
12812   /* Now we know the size of the symtab section.  */
12813   if (bfd_get_symcount (abfd) > 0)
12814     {
12815       /* Finish up and write out the symbol string table (.strtab)
12816 	 section.  */
12817       Elf_Internal_Shdr *symstrtab_hdr = NULL;
12818       file_ptr off = symtab_hdr->sh_offset + symtab_hdr->sh_size;
12819 
12820       if (elf_symtab_shndx_list (abfd))
12821 	{
12822 	  symtab_shndx_hdr = & elf_symtab_shndx_list (abfd)->hdr;
12823 
12824 	  if (symtab_shndx_hdr != NULL && symtab_shndx_hdr->sh_name != 0)
12825 	    {
12826 	      symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
12827 	      symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
12828 	      symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
12829 	      amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
12830 	      symtab_shndx_hdr->sh_size = amt;
12831 
12832 	      off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
12833 							       off, true);
12834 
12835 	      if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
12836 		  || (bfd_bwrite (flinfo.symshndxbuf, amt, abfd) != amt))
12837 		{
12838 		  ret = false;
12839 		  goto return_local_hash_table;
12840 		}
12841 	    }
12842 	}
12843 
12844       symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
12845       /* sh_name was set in prep_headers.  */
12846       symstrtab_hdr->sh_type = SHT_STRTAB;
12847       symstrtab_hdr->sh_flags = bed->elf_strtab_flags;
12848       symstrtab_hdr->sh_addr = 0;
12849       symstrtab_hdr->sh_size = _bfd_elf_strtab_size (flinfo.symstrtab);
12850       symstrtab_hdr->sh_entsize = 0;
12851       symstrtab_hdr->sh_link = 0;
12852       symstrtab_hdr->sh_info = 0;
12853       /* sh_offset is set just below.  */
12854       symstrtab_hdr->sh_addralign = 1;
12855 
12856       off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr,
12857 						       off, true);
12858       elf_next_file_pos (abfd) = off;
12859 
12860       if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
12861 	  || ! _bfd_elf_strtab_emit (abfd, flinfo.symstrtab))
12862 	{
12863 	  ret = false;
12864 	  goto return_local_hash_table;
12865 	}
12866     }
12867 
12868   if (info->out_implib_bfd && !elf_output_implib (abfd, info))
12869     {
12870       _bfd_error_handler (_("%pB: failed to generate import library"),
12871 			  info->out_implib_bfd);
12872       ret = false;
12873       goto return_local_hash_table;
12874     }
12875 
12876   /* Adjust the relocs to have the correct symbol indices.  */
12877   for (o = abfd->sections; o != NULL; o = o->next)
12878     {
12879       struct bfd_elf_section_data *esdo = elf_section_data (o);
12880       bool sort;
12881 
12882       if ((o->flags & SEC_RELOC) == 0)
12883 	continue;
12884 
12885       sort = bed->sort_relocs_p == NULL || (*bed->sort_relocs_p) (o);
12886       if (esdo->rel.hdr != NULL
12887 	  && !elf_link_adjust_relocs (abfd, o, &esdo->rel, sort, info))
12888 	{
12889 	  ret = false;
12890 	  goto return_local_hash_table;
12891 	}
12892       if (esdo->rela.hdr != NULL
12893 	  && !elf_link_adjust_relocs (abfd, o, &esdo->rela, sort, info))
12894 	{
12895 	  ret = false;
12896 	  goto return_local_hash_table;
12897 	}
12898 
12899       /* Set the reloc_count field to 0 to prevent write_relocs from
12900 	 trying to swap the relocs out itself.  */
12901       o->reloc_count = 0;
12902     }
12903 
12904   if (dynamic && info->combreloc && dynobj != NULL)
12905     relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
12906 
12907   /* If we are linking against a dynamic object, or generating a
12908      shared library, finish up the dynamic linking information.  */
12909   if (dynamic)
12910     {
12911       bfd_byte *dyncon, *dynconend;
12912 
12913       /* Fix up .dynamic entries.  */
12914       o = bfd_get_linker_section (dynobj, ".dynamic");
12915       BFD_ASSERT (o != NULL);
12916 
12917       dyncon = o->contents;
12918       dynconend = o->contents + o->size;
12919       for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
12920 	{
12921 	  Elf_Internal_Dyn dyn;
12922 	  const char *name;
12923 	  unsigned int type;
12924 	  bfd_size_type sh_size;
12925 	  bfd_vma sh_addr;
12926 
12927 	  bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
12928 
12929 	  switch (dyn.d_tag)
12930 	    {
12931 	    default:
12932 	      continue;
12933 	    case DT_NULL:
12934 	      if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
12935 		{
12936 		  switch (elf_section_data (reldyn)->this_hdr.sh_type)
12937 		    {
12938 		    case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
12939 		    case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
12940 		    default: continue;
12941 		    }
12942 		  dyn.d_un.d_val = relativecount;
12943 		  relativecount = 0;
12944 		  break;
12945 		}
12946 	      continue;
12947 
12948 	    case DT_INIT:
12949 	      name = info->init_function;
12950 	      goto get_sym;
12951 	    case DT_FINI:
12952 	      name = info->fini_function;
12953 	    get_sym:
12954 	      {
12955 		struct elf_link_hash_entry *h;
12956 
12957 		h = elf_link_hash_lookup (htab, name, false, false, true);
12958 		if (h != NULL
12959 		    && (h->root.type == bfd_link_hash_defined
12960 			|| h->root.type == bfd_link_hash_defweak))
12961 		  {
12962 		    dyn.d_un.d_ptr = h->root.u.def.value;
12963 		    o = h->root.u.def.section;
12964 		    if (o->output_section != NULL)
12965 		      dyn.d_un.d_ptr += (o->output_section->vma
12966 					 + o->output_offset);
12967 		    else
12968 		      {
12969 			/* The symbol is imported from another shared
12970 			   library and does not apply to this one.  */
12971 			dyn.d_un.d_ptr = 0;
12972 		      }
12973 		    break;
12974 		  }
12975 	      }
12976 	      continue;
12977 
12978 	    case DT_PREINIT_ARRAYSZ:
12979 	      name = ".preinit_array";
12980 	      goto get_out_size;
12981 	    case DT_INIT_ARRAYSZ:
12982 	      name = ".init_array";
12983 	      goto get_out_size;
12984 	    case DT_FINI_ARRAYSZ:
12985 	      name = ".fini_array";
12986 	    get_out_size:
12987 	      o = bfd_get_section_by_name (abfd, name);
12988 	      if (o == NULL)
12989 		{
12990 		  _bfd_error_handler
12991 		    (_("could not find section %s"), name);
12992 		  goto error_return;
12993 		}
12994 	      if (o->size == 0)
12995 		_bfd_error_handler
12996 		  (_("warning: %s section has zero size"), name);
12997 	      dyn.d_un.d_val = o->size;
12998 	      break;
12999 
13000 	    case DT_PREINIT_ARRAY:
13001 	      name = ".preinit_array";
13002 	      goto get_out_vma;
13003 	    case DT_INIT_ARRAY:
13004 	      name = ".init_array";
13005 	      goto get_out_vma;
13006 	    case DT_FINI_ARRAY:
13007 	      name = ".fini_array";
13008 	    get_out_vma:
13009 	      o = bfd_get_section_by_name (abfd, name);
13010 	      goto do_vma;
13011 
13012 	    case DT_HASH:
13013 	      name = ".hash";
13014 	      goto get_vma;
13015 	    case DT_GNU_HASH:
13016 	      name = ".gnu.hash";
13017 	      goto get_vma;
13018 	    case DT_STRTAB:
13019 	      name = ".dynstr";
13020 	      goto get_vma;
13021 	    case DT_SYMTAB:
13022 	      name = ".dynsym";
13023 	      goto get_vma;
13024 	    case DT_VERDEF:
13025 	      name = ".gnu.version_d";
13026 	      goto get_vma;
13027 	    case DT_VERNEED:
13028 	      name = ".gnu.version_r";
13029 	      goto get_vma;
13030 	    case DT_VERSYM:
13031 	      name = ".gnu.version";
13032 	    get_vma:
13033 	      o = bfd_get_linker_section (dynobj, name);
13034 	    do_vma:
13035 	      if (o == NULL || bfd_is_abs_section (o->output_section))
13036 		{
13037 		  _bfd_error_handler
13038 		    (_("could not find section %s"), name);
13039 		  goto error_return;
13040 		}
13041 	      if (elf_section_data (o->output_section)->this_hdr.sh_type == SHT_NOTE)
13042 		{
13043 		  _bfd_error_handler
13044 		    (_("warning: section '%s' is being made into a note"), name);
13045 		  bfd_set_error (bfd_error_nonrepresentable_section);
13046 		  goto error_return;
13047 		}
13048 	      dyn.d_un.d_ptr = o->output_section->vma + o->output_offset;
13049 	      break;
13050 
13051 	    case DT_REL:
13052 	    case DT_RELA:
13053 	    case DT_RELSZ:
13054 	    case DT_RELASZ:
13055 	      if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
13056 		type = SHT_REL;
13057 	      else
13058 		type = SHT_RELA;
13059 	      sh_size = 0;
13060 	      sh_addr = 0;
13061 	      for (i = 1; i < elf_numsections (abfd); i++)
13062 		{
13063 		  Elf_Internal_Shdr *hdr;
13064 
13065 		  hdr = elf_elfsections (abfd)[i];
13066 		  if (hdr->sh_type == type
13067 		      && (hdr->sh_flags & SHF_ALLOC) != 0)
13068 		    {
13069 		      sh_size += hdr->sh_size;
13070 		      if (sh_addr == 0
13071 			  || sh_addr > hdr->sh_addr)
13072 			sh_addr = hdr->sh_addr;
13073 		    }
13074 		}
13075 
13076 	      if (bed->dtrel_excludes_plt && htab->srelplt != NULL)
13077 		{
13078 		  unsigned int opb = bfd_octets_per_byte (abfd, o);
13079 
13080 		  /* Don't count procedure linkage table relocs in the
13081 		     overall reloc count.  */
13082 		  sh_size -= htab->srelplt->size;
13083 		  if (sh_size == 0)
13084 		    /* If the size is zero, make the address zero too.
13085 		       This is to avoid a glibc bug.  If the backend
13086 		       emits DT_RELA/DT_RELASZ even when DT_RELASZ is
13087 		       zero, then we'll put DT_RELA at the end of
13088 		       DT_JMPREL.  glibc will interpret the end of
13089 		       DT_RELA matching the end of DT_JMPREL as the
13090 		       case where DT_RELA includes DT_JMPREL, and for
13091 		       LD_BIND_NOW will decide that processing DT_RELA
13092 		       will process the PLT relocs too.  Net result:
13093 		       No PLT relocs applied.  */
13094 		    sh_addr = 0;
13095 
13096 		  /* If .rela.plt is the first .rela section, exclude
13097 		     it from DT_RELA.  */
13098 		  else if (sh_addr == (htab->srelplt->output_section->vma
13099 				       + htab->srelplt->output_offset) * opb)
13100 		    sh_addr += htab->srelplt->size;
13101 		}
13102 
13103 	      if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
13104 		dyn.d_un.d_val = sh_size;
13105 	      else
13106 		dyn.d_un.d_ptr = sh_addr;
13107 	      break;
13108 	    }
13109 	  bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
13110 	}
13111     }
13112 
13113   /* If we have created any dynamic sections, then output them.  */
13114   if (dynobj != NULL)
13115     {
13116       if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
13117 	goto error_return;
13118 
13119       /* Check for DT_TEXTREL (late, in case the backend removes it).  */
13120       if (bfd_link_textrel_check (info)
13121 	  && (o = bfd_get_linker_section (dynobj, ".dynamic")) != NULL)
13122 	{
13123 	  bfd_byte *dyncon, *dynconend;
13124 
13125 	  dyncon = o->contents;
13126 	  dynconend = o->contents + o->size;
13127 	  for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
13128 	    {
13129 	      Elf_Internal_Dyn dyn;
13130 
13131 	      bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
13132 
13133 	      if (dyn.d_tag == DT_TEXTREL)
13134 		{
13135 		  if (info->textrel_check == textrel_check_error)
13136 		    info->callbacks->einfo
13137 		      (_("%P%X: read-only segment has dynamic relocations\n"));
13138 		  else if (bfd_link_dll (info))
13139 		    info->callbacks->einfo
13140 		      (_("%P: warning: creating DT_TEXTREL in a shared object\n"));
13141 		  else if (bfd_link_pde (info))
13142 		    info->callbacks->einfo
13143 		      (_("%P: warning: creating DT_TEXTREL in a PDE\n"));
13144 		  else
13145 		    info->callbacks->einfo
13146 		      (_("%P: warning: creating DT_TEXTREL in a PIE\n"));
13147 		  break;
13148 		}
13149 	    }
13150 	}
13151 
13152       for (o = dynobj->sections; o != NULL; o = o->next)
13153 	{
13154 	  if ((o->flags & SEC_HAS_CONTENTS) == 0
13155 	      || o->size == 0
13156 	      || o->output_section == bfd_abs_section_ptr)
13157 	    continue;
13158 	  if ((o->flags & SEC_LINKER_CREATED) == 0)
13159 	    {
13160 	      /* At this point, we are only interested in sections
13161 		 created by _bfd_elf_link_create_dynamic_sections.  */
13162 	      continue;
13163 	    }
13164 	  if (htab->stab_info.stabstr == o)
13165 	    continue;
13166 	  if (htab->eh_info.hdr_sec == o)
13167 	    continue;
13168 	  if (strcmp (o->name, ".dynstr") != 0)
13169 	    {
13170 	      bfd_size_type octets = ((file_ptr) o->output_offset
13171 				      * bfd_octets_per_byte (abfd, o));
13172 	      if (!bfd_set_section_contents (abfd, o->output_section,
13173 					     o->contents, octets, o->size))
13174 		goto error_return;
13175 	    }
13176 	  else
13177 	    {
13178 	      /* The contents of the .dynstr section are actually in a
13179 		 stringtab.  */
13180 	      file_ptr off;
13181 
13182 	      off = elf_section_data (o->output_section)->this_hdr.sh_offset;
13183 	      if (bfd_seek (abfd, off, SEEK_SET) != 0
13184 		  || !_bfd_elf_strtab_emit (abfd, htab->dynstr))
13185 		goto error_return;
13186 	    }
13187 	}
13188     }
13189 
13190   if (!info->resolve_section_groups)
13191     {
13192       bool failed = false;
13193 
13194       BFD_ASSERT (bfd_link_relocatable (info));
13195       bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
13196       if (failed)
13197 	goto error_return;
13198     }
13199 
13200   /* If we have optimized stabs strings, output them.  */
13201   if (htab->stab_info.stabstr != NULL)
13202     {
13203       if (!_bfd_write_stab_strings (abfd, &htab->stab_info))
13204 	goto error_return;
13205     }
13206 
13207   if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
13208     goto error_return;
13209 
13210   if (info->callbacks->emit_ctf)
13211       info->callbacks->emit_ctf ();
13212 
13213   elf_final_link_free (abfd, &flinfo);
13214 
13215   if (attr_section)
13216     {
13217       bfd_byte *contents = (bfd_byte *) bfd_malloc (attr_size);
13218       if (contents == NULL)
13219 	{
13220 	  /* Bail out and fail.  */
13221 	  ret = false;
13222 	  goto return_local_hash_table;
13223 	}
13224       bfd_elf_set_obj_attr_contents (abfd, contents, attr_size);
13225       bfd_set_section_contents (abfd, attr_section, contents, 0, attr_size);
13226       free (contents);
13227     }
13228 
13229  return_local_hash_table:
13230   if (info->unique_symbol)
13231     bfd_hash_table_free (&flinfo.local_hash_table);
13232   return ret;
13233 
13234  error_return:
13235   elf_final_link_free (abfd, &flinfo);
13236   ret = false;
13237   goto return_local_hash_table;
13238 }
13239 
13240 /* Initialize COOKIE for input bfd ABFD.  */
13241 
13242 static bool
init_reloc_cookie(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,bfd * abfd)13243 init_reloc_cookie (struct elf_reloc_cookie *cookie,
13244 		   struct bfd_link_info *info, bfd *abfd)
13245 {
13246   Elf_Internal_Shdr *symtab_hdr;
13247   const struct elf_backend_data *bed;
13248 
13249   bed = get_elf_backend_data (abfd);
13250   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
13251 
13252   cookie->abfd = abfd;
13253   cookie->sym_hashes = elf_sym_hashes (abfd);
13254   cookie->bad_symtab = elf_bad_symtab (abfd);
13255   if (cookie->bad_symtab)
13256     {
13257       cookie->locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
13258       cookie->extsymoff = 0;
13259     }
13260   else
13261     {
13262       cookie->locsymcount = symtab_hdr->sh_info;
13263       cookie->extsymoff = symtab_hdr->sh_info;
13264     }
13265 
13266   if (bed->s->arch_size == 32)
13267     cookie->r_sym_shift = 8;
13268   else
13269     cookie->r_sym_shift = 32;
13270 
13271   cookie->locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
13272   if (cookie->locsyms == NULL && cookie->locsymcount != 0)
13273     {
13274       cookie->locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
13275 					      cookie->locsymcount, 0,
13276 					      NULL, NULL, NULL);
13277       if (cookie->locsyms == NULL)
13278 	{
13279 	  info->callbacks->einfo (_("%P%X: can not read symbols: %E\n"));
13280 	  return false;
13281 	}
13282       if (info->keep_memory)
13283 	symtab_hdr->contents = (bfd_byte *) cookie->locsyms;
13284     }
13285   return true;
13286 }
13287 
13288 /* Free the memory allocated by init_reloc_cookie, if appropriate.  */
13289 
13290 static void
fini_reloc_cookie(struct elf_reloc_cookie * cookie,bfd * abfd)13291 fini_reloc_cookie (struct elf_reloc_cookie *cookie, bfd *abfd)
13292 {
13293   Elf_Internal_Shdr *symtab_hdr;
13294 
13295   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
13296   if (symtab_hdr->contents != (unsigned char *) cookie->locsyms)
13297     free (cookie->locsyms);
13298 }
13299 
13300 /* Initialize the relocation information in COOKIE for input section SEC
13301    of input bfd ABFD.  */
13302 
13303 static bool
init_reloc_cookie_rels(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,bfd * abfd,asection * sec)13304 init_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
13305 			struct bfd_link_info *info, bfd *abfd,
13306 			asection *sec)
13307 {
13308   if (sec->reloc_count == 0)
13309     {
13310       cookie->rels = NULL;
13311       cookie->relend = NULL;
13312     }
13313   else
13314     {
13315       cookie->rels = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
13316 						info->keep_memory);
13317       if (cookie->rels == NULL)
13318 	return false;
13319       cookie->rel = cookie->rels;
13320       cookie->relend = cookie->rels + sec->reloc_count;
13321     }
13322   cookie->rel = cookie->rels;
13323   return true;
13324 }
13325 
13326 /* Free the memory allocated by init_reloc_cookie_rels,
13327    if appropriate.  */
13328 
13329 static void
fini_reloc_cookie_rels(struct elf_reloc_cookie * cookie,asection * sec)13330 fini_reloc_cookie_rels (struct elf_reloc_cookie *cookie,
13331 			asection *sec)
13332 {
13333   if (elf_section_data (sec)->relocs != cookie->rels)
13334     free (cookie->rels);
13335 }
13336 
13337 /* Initialize the whole of COOKIE for input section SEC.  */
13338 
13339 static bool
init_reloc_cookie_for_section(struct elf_reloc_cookie * cookie,struct bfd_link_info * info,asection * sec)13340 init_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
13341 			       struct bfd_link_info *info,
13342 			       asection *sec)
13343 {
13344   if (!init_reloc_cookie (cookie, info, sec->owner))
13345     goto error1;
13346   if (!init_reloc_cookie_rels (cookie, info, sec->owner, sec))
13347     goto error2;
13348   return true;
13349 
13350  error2:
13351   fini_reloc_cookie (cookie, sec->owner);
13352  error1:
13353   return false;
13354 }
13355 
13356 /* Free the memory allocated by init_reloc_cookie_for_section,
13357    if appropriate.  */
13358 
13359 static void
fini_reloc_cookie_for_section(struct elf_reloc_cookie * cookie,asection * sec)13360 fini_reloc_cookie_for_section (struct elf_reloc_cookie *cookie,
13361 			       asection *sec)
13362 {
13363   fini_reloc_cookie_rels (cookie, sec);
13364   fini_reloc_cookie (cookie, sec->owner);
13365 }
13366 
13367 /* Garbage collect unused sections.  */
13368 
13369 /* Default gc_mark_hook.  */
13370 
13371 asection *
_bfd_elf_gc_mark_hook(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)13372 _bfd_elf_gc_mark_hook (asection *sec,
13373 		       struct bfd_link_info *info ATTRIBUTE_UNUSED,
13374 		       Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
13375 		       struct elf_link_hash_entry *h,
13376 		       Elf_Internal_Sym *sym)
13377 {
13378   if (h != NULL)
13379     {
13380       switch (h->root.type)
13381 	{
13382 	case bfd_link_hash_defined:
13383 	case bfd_link_hash_defweak:
13384 	  return h->root.u.def.section;
13385 
13386 	case bfd_link_hash_common:
13387 	  return h->root.u.c.p->section;
13388 
13389 	default:
13390 	  break;
13391 	}
13392     }
13393   else
13394     return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
13395 
13396   return NULL;
13397 }
13398 
13399 /* Return the debug definition section.  */
13400 
13401 static asection *
elf_gc_mark_debug_section(asection * sec ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)13402 elf_gc_mark_debug_section (asection *sec ATTRIBUTE_UNUSED,
13403 			   struct bfd_link_info *info ATTRIBUTE_UNUSED,
13404 			   Elf_Internal_Rela *rel ATTRIBUTE_UNUSED,
13405 			   struct elf_link_hash_entry *h,
13406 			   Elf_Internal_Sym *sym)
13407 {
13408   if (h != NULL)
13409     {
13410       /* Return the global debug definition section.  */
13411       if ((h->root.type == bfd_link_hash_defined
13412 	   || h->root.type == bfd_link_hash_defweak)
13413 	  && (h->root.u.def.section->flags & SEC_DEBUGGING) != 0)
13414 	return h->root.u.def.section;
13415     }
13416   else
13417     {
13418       /* Return the local debug definition section.  */
13419       asection *isec = bfd_section_from_elf_index (sec->owner,
13420 						   sym->st_shndx);
13421       if ((isec->flags & SEC_DEBUGGING) != 0)
13422 	return isec;
13423     }
13424 
13425   return NULL;
13426 }
13427 
13428 /* COOKIE->rel describes a relocation against section SEC, which is
13429    a section we've decided to keep.  Return the section that contains
13430    the relocation symbol, or NULL if no section contains it.  */
13431 
13432 asection *
_bfd_elf_gc_mark_rsec(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook,struct elf_reloc_cookie * cookie,bool * start_stop)13433 _bfd_elf_gc_mark_rsec (struct bfd_link_info *info, asection *sec,
13434 		       elf_gc_mark_hook_fn gc_mark_hook,
13435 		       struct elf_reloc_cookie *cookie,
13436 		       bool *start_stop)
13437 {
13438   unsigned long r_symndx;
13439   struct elf_link_hash_entry *h, *hw;
13440 
13441   r_symndx = cookie->rel->r_info >> cookie->r_sym_shift;
13442   if (r_symndx == STN_UNDEF)
13443     return NULL;
13444 
13445   if (r_symndx >= cookie->locsymcount
13446       || ELF_ST_BIND (cookie->locsyms[r_symndx].st_info) != STB_LOCAL)
13447     {
13448       bool was_marked;
13449 
13450       h = cookie->sym_hashes[r_symndx - cookie->extsymoff];
13451       if (h == NULL)
13452 	{
13453 	  info->callbacks->einfo (_("%F%P: corrupt input: %pB\n"),
13454 				  sec->owner);
13455 	  return NULL;
13456 	}
13457       while (h->root.type == bfd_link_hash_indirect
13458 	     || h->root.type == bfd_link_hash_warning)
13459 	h = (struct elf_link_hash_entry *) h->root.u.i.link;
13460 
13461       was_marked = h->mark;
13462       h->mark = 1;
13463       /* Keep all aliases of the symbol too.  If an object symbol
13464 	 needs to be copied into .dynbss then all of its aliases
13465 	 should be present as dynamic symbols, not just the one used
13466 	 on the copy relocation.  */
13467       hw = h;
13468       while (hw->is_weakalias)
13469 	{
13470 	  hw = hw->u.alias;
13471 	  hw->mark = 1;
13472 	}
13473 
13474       if (!was_marked && h->start_stop && !h->root.ldscript_def)
13475 	{
13476 	  if (info->start_stop_gc)
13477 	    return NULL;
13478 
13479 	  /* To work around a glibc bug, mark XXX input sections
13480 	     when there is a reference to __start_XXX or __stop_XXX
13481 	     symbols.  */
13482 	  else if (start_stop != NULL)
13483 	    {
13484 	      asection *s = h->u2.start_stop_section;
13485 	      *start_stop = true;
13486 	      return s;
13487 	    }
13488 	}
13489 
13490       return (*gc_mark_hook) (sec, info, cookie->rel, h, NULL);
13491     }
13492 
13493   return (*gc_mark_hook) (sec, info, cookie->rel, NULL,
13494 			  &cookie->locsyms[r_symndx]);
13495 }
13496 
13497 /* COOKIE->rel describes a relocation against section SEC, which is
13498    a section we've decided to keep.  Mark the section that contains
13499    the relocation symbol.  */
13500 
13501 bool
_bfd_elf_gc_mark_reloc(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook,struct elf_reloc_cookie * cookie)13502 _bfd_elf_gc_mark_reloc (struct bfd_link_info *info,
13503 			asection *sec,
13504 			elf_gc_mark_hook_fn gc_mark_hook,
13505 			struct elf_reloc_cookie *cookie)
13506 {
13507   asection *rsec;
13508   bool start_stop = false;
13509 
13510   rsec = _bfd_elf_gc_mark_rsec (info, sec, gc_mark_hook, cookie, &start_stop);
13511   while (rsec != NULL)
13512     {
13513       if (!rsec->gc_mark)
13514 	{
13515 	  if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour
13516 	      || (rsec->owner->flags & DYNAMIC) != 0)
13517 	    rsec->gc_mark = 1;
13518 	  else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
13519 	    return false;
13520 	}
13521       if (!start_stop)
13522 	break;
13523       rsec = bfd_get_next_section_by_name (rsec->owner, rsec);
13524     }
13525   return true;
13526 }
13527 
13528 /* The mark phase of garbage collection.  For a given section, mark
13529    it and any sections in this section's group, and all the sections
13530    which define symbols to which it refers.  */
13531 
13532 bool
_bfd_elf_gc_mark(struct bfd_link_info * info,asection * sec,elf_gc_mark_hook_fn gc_mark_hook)13533 _bfd_elf_gc_mark (struct bfd_link_info *info,
13534 		  asection *sec,
13535 		  elf_gc_mark_hook_fn gc_mark_hook)
13536 {
13537   bool ret;
13538   asection *group_sec, *eh_frame;
13539 
13540   sec->gc_mark = 1;
13541 
13542   /* Mark all the sections in the group.  */
13543   group_sec = elf_section_data (sec)->next_in_group;
13544   if (group_sec && !group_sec->gc_mark)
13545     if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
13546       return false;
13547 
13548   /* Look through the section relocs.  */
13549   ret = true;
13550   eh_frame = elf_eh_frame_section (sec->owner);
13551   if ((sec->flags & SEC_RELOC) != 0
13552       && sec->reloc_count > 0
13553       && sec != eh_frame)
13554     {
13555       struct elf_reloc_cookie cookie;
13556 
13557       if (!init_reloc_cookie_for_section (&cookie, info, sec))
13558 	ret = false;
13559       else
13560 	{
13561 	  for (; cookie.rel < cookie.relend; cookie.rel++)
13562 	    if (!_bfd_elf_gc_mark_reloc (info, sec, gc_mark_hook, &cookie))
13563 	      {
13564 		ret = false;
13565 		break;
13566 	      }
13567 	  fini_reloc_cookie_for_section (&cookie, sec);
13568 	}
13569     }
13570 
13571   if (ret && eh_frame && elf_fde_list (sec))
13572     {
13573       struct elf_reloc_cookie cookie;
13574 
13575       if (!init_reloc_cookie_for_section (&cookie, info, eh_frame))
13576 	ret = false;
13577       else
13578 	{
13579 	  if (!_bfd_elf_gc_mark_fdes (info, sec, eh_frame,
13580 				      gc_mark_hook, &cookie))
13581 	    ret = false;
13582 	  fini_reloc_cookie_for_section (&cookie, eh_frame);
13583 	}
13584     }
13585 
13586   eh_frame = elf_section_eh_frame_entry (sec);
13587   if (ret && eh_frame && !eh_frame->gc_mark)
13588     if (!_bfd_elf_gc_mark (info, eh_frame, gc_mark_hook))
13589       ret = false;
13590 
13591   return ret;
13592 }
13593 
13594 /* Scan and mark sections in a special or debug section group.  */
13595 
13596 static void
_bfd_elf_gc_mark_debug_special_section_group(asection * grp)13597 _bfd_elf_gc_mark_debug_special_section_group (asection *grp)
13598 {
13599   /* Point to first section of section group.  */
13600   asection *ssec;
13601   /* Used to iterate the section group.  */
13602   asection *msec;
13603 
13604   bool is_special_grp = true;
13605   bool is_debug_grp = true;
13606 
13607   /* First scan to see if group contains any section other than debug
13608      and special section.  */
13609   ssec = msec = elf_next_in_group (grp);
13610   do
13611     {
13612       if ((msec->flags & SEC_DEBUGGING) == 0)
13613 	is_debug_grp = false;
13614 
13615       if ((msec->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) != 0)
13616 	is_special_grp = false;
13617 
13618       msec = elf_next_in_group (msec);
13619     }
13620   while (msec != ssec);
13621 
13622   /* If this is a pure debug section group or pure special section group,
13623      keep all sections in this group.  */
13624   if (is_debug_grp || is_special_grp)
13625     {
13626       do
13627 	{
13628 	  msec->gc_mark = 1;
13629 	  msec = elf_next_in_group (msec);
13630 	}
13631       while (msec != ssec);
13632     }
13633 }
13634 
13635 /* Keep debug and special sections.  */
13636 
13637 bool
_bfd_elf_gc_mark_extra_sections(struct bfd_link_info * info,elf_gc_mark_hook_fn mark_hook)13638 _bfd_elf_gc_mark_extra_sections (struct bfd_link_info *info,
13639 				 elf_gc_mark_hook_fn mark_hook)
13640 {
13641   bfd *ibfd;
13642 
13643   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
13644     {
13645       asection *isec;
13646       bool some_kept;
13647       bool debug_frag_seen;
13648       bool has_kept_debug_info;
13649 
13650       if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
13651 	continue;
13652       isec = ibfd->sections;
13653       if (isec == NULL || isec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
13654 	continue;
13655 
13656       /* Ensure all linker created sections are kept,
13657 	 see if any other section is already marked,
13658 	 and note if we have any fragmented debug sections.  */
13659       debug_frag_seen = some_kept = has_kept_debug_info = false;
13660       for (isec = ibfd->sections; isec != NULL; isec = isec->next)
13661 	{
13662 	  if ((isec->flags & SEC_LINKER_CREATED) != 0)
13663 	    isec->gc_mark = 1;
13664 	  else if (isec->gc_mark
13665 		   && (isec->flags & SEC_ALLOC) != 0
13666 		   && elf_section_type (isec) != SHT_NOTE)
13667 	    some_kept = true;
13668 	  else
13669 	    {
13670 	      /* Since all sections, except for backend specific ones,
13671 		 have been garbage collected, call mark_hook on this
13672 		 section if any of its linked-to sections is marked.  */
13673 	      asection *linked_to_sec;
13674 	      for (linked_to_sec = elf_linked_to_section (isec);
13675 		   linked_to_sec != NULL && !linked_to_sec->linker_mark;
13676 		   linked_to_sec = elf_linked_to_section (linked_to_sec))
13677 		{
13678 		  if (linked_to_sec->gc_mark)
13679 		    {
13680 		      if (!_bfd_elf_gc_mark (info, isec, mark_hook))
13681 			return false;
13682 		      break;
13683 		    }
13684 		  linked_to_sec->linker_mark = 1;
13685 		}
13686 	      for (linked_to_sec = elf_linked_to_section (isec);
13687 		   linked_to_sec != NULL && linked_to_sec->linker_mark;
13688 		   linked_to_sec = elf_linked_to_section (linked_to_sec))
13689 		linked_to_sec->linker_mark = 0;
13690 	    }
13691 
13692 	  if (!debug_frag_seen
13693 	      && (isec->flags & SEC_DEBUGGING)
13694 	      && startswith (isec->name, ".debug_line."))
13695 	    debug_frag_seen = true;
13696 	  else if (strcmp (bfd_section_name (isec),
13697 			   "__patchable_function_entries") == 0
13698 		   && elf_linked_to_section (isec) == NULL)
13699 	      info->callbacks->einfo (_("%F%P: %pB(%pA): error: "
13700 					"need linked-to section "
13701 					"for --gc-sections\n"),
13702 				      isec->owner, isec);
13703 	}
13704 
13705       /* If no non-note alloc section in this file will be kept, then
13706 	 we can toss out the debug and special sections.  */
13707       if (!some_kept)
13708 	continue;
13709 
13710       /* Keep debug and special sections like .comment when they are
13711 	 not part of a group.  Also keep section groups that contain
13712 	 just debug sections or special sections.  NB: Sections with
13713 	 linked-to section has been handled above.  */
13714       for (isec = ibfd->sections; isec != NULL; isec = isec->next)
13715 	{
13716 	  if ((isec->flags & SEC_GROUP) != 0)
13717 	    _bfd_elf_gc_mark_debug_special_section_group (isec);
13718 	  else if (((isec->flags & SEC_DEBUGGING) != 0
13719 		    || (isec->flags & (SEC_ALLOC | SEC_LOAD | SEC_RELOC)) == 0)
13720 		   && elf_next_in_group (isec) == NULL
13721 		   && elf_linked_to_section (isec) == NULL)
13722 	    isec->gc_mark = 1;
13723 	  if (isec->gc_mark && (isec->flags & SEC_DEBUGGING) != 0)
13724 	    has_kept_debug_info = true;
13725 	}
13726 
13727       /* Look for CODE sections which are going to be discarded,
13728 	 and find and discard any fragmented debug sections which
13729 	 are associated with that code section.  */
13730       if (debug_frag_seen)
13731 	for (isec = ibfd->sections; isec != NULL; isec = isec->next)
13732 	  if ((isec->flags & SEC_CODE) != 0
13733 	      && isec->gc_mark == 0)
13734 	    {
13735 	      unsigned int ilen;
13736 	      asection *dsec;
13737 
13738 	      ilen = strlen (isec->name);
13739 
13740 	      /* Association is determined by the name of the debug
13741 		 section containing the name of the code section as
13742 		 a suffix.  For example .debug_line.text.foo is a
13743 		 debug section associated with .text.foo.  */
13744 	      for (dsec = ibfd->sections; dsec != NULL; dsec = dsec->next)
13745 		{
13746 		  unsigned int dlen;
13747 
13748 		  if (dsec->gc_mark == 0
13749 		      || (dsec->flags & SEC_DEBUGGING) == 0)
13750 		    continue;
13751 
13752 		  dlen = strlen (dsec->name);
13753 
13754 		  if (dlen > ilen
13755 		      && strncmp (dsec->name + (dlen - ilen),
13756 				  isec->name, ilen) == 0)
13757 		    dsec->gc_mark = 0;
13758 		}
13759 	  }
13760 
13761       /* Mark debug sections referenced by kept debug sections.  */
13762       if (has_kept_debug_info)
13763 	for (isec = ibfd->sections; isec != NULL; isec = isec->next)
13764 	  if (isec->gc_mark
13765 	      && (isec->flags & SEC_DEBUGGING) != 0)
13766 	    if (!_bfd_elf_gc_mark (info, isec,
13767 				   elf_gc_mark_debug_section))
13768 	      return false;
13769     }
13770   return true;
13771 }
13772 
13773 static bool
elf_gc_sweep(bfd * abfd,struct bfd_link_info * info)13774 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
13775 {
13776   bfd *sub;
13777   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
13778 
13779   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
13780     {
13781       asection *o;
13782 
13783       if (bfd_get_flavour (sub) != bfd_target_elf_flavour
13784 	  || elf_object_id (sub) != elf_hash_table_id (elf_hash_table (info))
13785 	  || !(*bed->relocs_compatible) (sub->xvec, abfd->xvec))
13786 	continue;
13787       o = sub->sections;
13788       if (o == NULL || o->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
13789 	continue;
13790 
13791       for (o = sub->sections; o != NULL; o = o->next)
13792 	{
13793 	  /* When any section in a section group is kept, we keep all
13794 	     sections in the section group.  If the first member of
13795 	     the section group is excluded, we will also exclude the
13796 	     group section.  */
13797 	  if (o->flags & SEC_GROUP)
13798 	    {
13799 	      asection *first = elf_next_in_group (o);
13800 	      o->gc_mark = first->gc_mark;
13801 	    }
13802 
13803 	  if (o->gc_mark)
13804 	    continue;
13805 
13806 	  /* Skip sweeping sections already excluded.  */
13807 	  if (o->flags & SEC_EXCLUDE)
13808 	    continue;
13809 
13810 	  /* Since this is early in the link process, it is simple
13811 	     to remove a section from the output.  */
13812 	  o->flags |= SEC_EXCLUDE;
13813 
13814 	  if (info->print_gc_sections && o->size != 0)
13815 	    /* xgettext:c-format */
13816 	    _bfd_error_handler (_("removing unused section '%pA' in file '%pB'"),
13817 				o, sub);
13818 	}
13819     }
13820 
13821   return true;
13822 }
13823 
13824 /* Propagate collected vtable information.  This is called through
13825    elf_link_hash_traverse.  */
13826 
13827 static bool
elf_gc_propagate_vtable_entries_used(struct elf_link_hash_entry * h,void * okp)13828 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
13829 {
13830   /* Those that are not vtables.  */
13831   if (h->start_stop
13832       || h->u2.vtable == NULL
13833       || h->u2.vtable->parent == NULL)
13834     return true;
13835 
13836   /* Those vtables that do not have parents, we cannot merge.  */
13837   if (h->u2.vtable->parent == (struct elf_link_hash_entry *) -1)
13838     return true;
13839 
13840   /* If we've already been done, exit.  */
13841   if (h->u2.vtable->used && h->u2.vtable->used[-1])
13842     return true;
13843 
13844   /* Make sure the parent's table is up to date.  */
13845   elf_gc_propagate_vtable_entries_used (h->u2.vtable->parent, okp);
13846 
13847   if (h->u2.vtable->used == NULL)
13848     {
13849       /* None of this table's entries were referenced.  Re-use the
13850 	 parent's table.  */
13851       h->u2.vtable->used = h->u2.vtable->parent->u2.vtable->used;
13852       h->u2.vtable->size = h->u2.vtable->parent->u2.vtable->size;
13853     }
13854   else
13855     {
13856       size_t n;
13857       bool *cu, *pu;
13858 
13859       /* Or the parent's entries into ours.  */
13860       cu = h->u2.vtable->used;
13861       cu[-1] = true;
13862       pu = h->u2.vtable->parent->u2.vtable->used;
13863       if (pu != NULL)
13864 	{
13865 	  const struct elf_backend_data *bed;
13866 	  unsigned int log_file_align;
13867 
13868 	  bed = get_elf_backend_data (h->root.u.def.section->owner);
13869 	  log_file_align = bed->s->log_file_align;
13870 	  n = h->u2.vtable->parent->u2.vtable->size >> log_file_align;
13871 	  while (n--)
13872 	    {
13873 	      if (*pu)
13874 		*cu = true;
13875 	      pu++;
13876 	      cu++;
13877 	    }
13878 	}
13879     }
13880 
13881   return true;
13882 }
13883 
13884 static bool
elf_gc_smash_unused_vtentry_relocs(struct elf_link_hash_entry * h,void * okp)13885 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
13886 {
13887   asection *sec;
13888   bfd_vma hstart, hend;
13889   Elf_Internal_Rela *relstart, *relend, *rel;
13890   const struct elf_backend_data *bed;
13891   unsigned int log_file_align;
13892 
13893   /* Take care of both those symbols that do not describe vtables as
13894      well as those that are not loaded.  */
13895   if (h->start_stop
13896       || h->u2.vtable == NULL
13897       || h->u2.vtable->parent == NULL)
13898     return true;
13899 
13900   BFD_ASSERT (h->root.type == bfd_link_hash_defined
13901 	      || h->root.type == bfd_link_hash_defweak);
13902 
13903   sec = h->root.u.def.section;
13904   hstart = h->root.u.def.value;
13905   hend = hstart + h->size;
13906 
13907   relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, true);
13908   if (!relstart)
13909     return *(bool *) okp = false;
13910   bed = get_elf_backend_data (sec->owner);
13911   log_file_align = bed->s->log_file_align;
13912 
13913   relend = relstart + sec->reloc_count;
13914 
13915   for (rel = relstart; rel < relend; ++rel)
13916     if (rel->r_offset >= hstart && rel->r_offset < hend)
13917       {
13918 	/* If the entry is in use, do nothing.  */
13919 	if (h->u2.vtable->used
13920 	    && (rel->r_offset - hstart) < h->u2.vtable->size)
13921 	  {
13922 	    bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
13923 	    if (h->u2.vtable->used[entry])
13924 	      continue;
13925 	  }
13926 	/* Otherwise, kill it.  */
13927 	rel->r_offset = rel->r_info = rel->r_addend = 0;
13928       }
13929 
13930   return true;
13931 }
13932 
13933 /* Mark sections containing dynamically referenced symbols.  When
13934    building shared libraries, we must assume that any visible symbol is
13935    referenced.  */
13936 
13937 bool
bfd_elf_gc_mark_dynamic_ref_symbol(struct elf_link_hash_entry * h,void * inf)13938 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
13939 {
13940   struct bfd_link_info *info = (struct bfd_link_info *) inf;
13941   struct bfd_elf_dynamic_list *d = info->dynamic_list;
13942 
13943   if ((h->root.type == bfd_link_hash_defined
13944        || h->root.type == bfd_link_hash_defweak)
13945       && (!h->start_stop
13946 	  || h->root.ldscript_def
13947 	  || !info->start_stop_gc)
13948       && ((h->ref_dynamic && !h->forced_local)
13949 	  || ((h->def_regular || ELF_COMMON_DEF_P (h))
13950 	      && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
13951 	      && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN
13952 	      && (!bfd_link_executable (info)
13953 		  || info->gc_keep_exported
13954 		  || info->export_dynamic
13955 		  || (h->dynamic
13956 		      && d != NULL
13957 		      && (*d->match) (&d->head, NULL, h->root.root.string)))
13958 	      && (h->versioned >= versioned
13959 		  || !bfd_hide_sym_by_version (info->version_info,
13960 					       h->root.root.string)))))
13961     h->root.u.def.section->flags |= SEC_KEEP;
13962 
13963   return true;
13964 }
13965 
13966 /* Keep all sections containing symbols undefined on the command-line,
13967    and the section containing the entry symbol.  */
13968 
13969 void
_bfd_elf_gc_keep(struct bfd_link_info * info)13970 _bfd_elf_gc_keep (struct bfd_link_info *info)
13971 {
13972   struct bfd_sym_chain *sym;
13973 
13974   for (sym = info->gc_sym_list; sym != NULL; sym = sym->next)
13975     {
13976       struct elf_link_hash_entry *h;
13977 
13978       h = elf_link_hash_lookup (elf_hash_table (info), sym->name,
13979 				false, false, false);
13980 
13981       if (h != NULL
13982 	  && (h->root.type == bfd_link_hash_defined
13983 	      || h->root.type == bfd_link_hash_defweak)
13984 	  && !bfd_is_const_section (h->root.u.def.section))
13985 	h->root.u.def.section->flags |= SEC_KEEP;
13986     }
13987 }
13988 
13989 bool
bfd_elf_parse_eh_frame_entries(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)13990 bfd_elf_parse_eh_frame_entries (bfd *abfd ATTRIBUTE_UNUSED,
13991 				struct bfd_link_info *info)
13992 {
13993   bfd *ibfd = info->input_bfds;
13994 
13995   for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next)
13996     {
13997       asection *sec;
13998       struct elf_reloc_cookie cookie;
13999 
14000       if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
14001 	continue;
14002       sec = ibfd->sections;
14003       if (sec == NULL || sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14004 	continue;
14005 
14006       if (!init_reloc_cookie (&cookie, info, ibfd))
14007 	return false;
14008 
14009       for (sec = ibfd->sections; sec; sec = sec->next)
14010 	{
14011 	  if (startswith (bfd_section_name (sec), ".eh_frame_entry")
14012 	      && init_reloc_cookie_rels (&cookie, info, ibfd, sec))
14013 	    {
14014 	      _bfd_elf_parse_eh_frame_entry (info, sec, &cookie);
14015 	      fini_reloc_cookie_rels (&cookie, sec);
14016 	    }
14017 	}
14018     }
14019   return true;
14020 }
14021 
14022 /* Do mark and sweep of unused sections.  */
14023 
14024 bool
bfd_elf_gc_sections(bfd * abfd,struct bfd_link_info * info)14025 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
14026 {
14027   bool ok = true;
14028   bfd *sub;
14029   elf_gc_mark_hook_fn gc_mark_hook;
14030   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14031   struct elf_link_hash_table *htab;
14032 
14033   if (!bed->can_gc_sections
14034       || !is_elf_hash_table (info->hash))
14035     {
14036       _bfd_error_handler(_("warning: gc-sections option ignored"));
14037       return true;
14038     }
14039 
14040   bed->gc_keep (info);
14041   htab = elf_hash_table (info);
14042 
14043   /* Try to parse each bfd's .eh_frame section.  Point elf_eh_frame_section
14044      at the .eh_frame section if we can mark the FDEs individually.  */
14045   for (sub = info->input_bfds;
14046        info->eh_frame_hdr_type != COMPACT_EH_HDR && sub != NULL;
14047        sub = sub->link.next)
14048     {
14049       asection *sec;
14050       struct elf_reloc_cookie cookie;
14051 
14052       sec = sub->sections;
14053       if (sec == NULL || sec->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14054 	continue;
14055       sec = bfd_get_section_by_name (sub, ".eh_frame");
14056       while (sec && init_reloc_cookie_for_section (&cookie, info, sec))
14057 	{
14058 	  _bfd_elf_parse_eh_frame (sub, info, sec, &cookie);
14059 	  if (elf_section_data (sec)->sec_info
14060 	      && (sec->flags & SEC_LINKER_CREATED) == 0)
14061 	    elf_eh_frame_section (sub) = sec;
14062 	  fini_reloc_cookie_for_section (&cookie, sec);
14063 	  sec = bfd_get_next_section_by_name (NULL, sec);
14064 	}
14065     }
14066 
14067   /* Apply transitive closure to the vtable entry usage info.  */
14068   elf_link_hash_traverse (htab, elf_gc_propagate_vtable_entries_used, &ok);
14069   if (!ok)
14070     return false;
14071 
14072   /* Kill the vtable relocations that were not used.  */
14073   elf_link_hash_traverse (htab, elf_gc_smash_unused_vtentry_relocs, &ok);
14074   if (!ok)
14075     return false;
14076 
14077   /* Mark dynamically referenced symbols.  */
14078   if (htab->dynamic_sections_created || info->gc_keep_exported)
14079     elf_link_hash_traverse (htab, bed->gc_mark_dynamic_ref, info);
14080 
14081   /* Grovel through relocs to find out who stays ...  */
14082   gc_mark_hook = bed->gc_mark_hook;
14083   for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
14084     {
14085       asection *o;
14086 
14087       if (bfd_get_flavour (sub) != bfd_target_elf_flavour
14088 	  || elf_object_id (sub) != elf_hash_table_id (htab)
14089 	  || !(*bed->relocs_compatible) (sub->xvec, abfd->xvec))
14090 	continue;
14091 
14092       o = sub->sections;
14093       if (o == NULL || o->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14094 	continue;
14095 
14096       /* Start at sections marked with SEC_KEEP (ref _bfd_elf_gc_keep).
14097 	 Also treat note sections as a root, if the section is not part
14098 	 of a group.  We must keep all PREINIT_ARRAY, INIT_ARRAY as
14099 	 well as FINI_ARRAY sections for ld -r.  */
14100       for (o = sub->sections; o != NULL; o = o->next)
14101 	if (!o->gc_mark
14102 	    && (o->flags & SEC_EXCLUDE) == 0
14103 	    && ((o->flags & SEC_KEEP) != 0
14104 		|| (bfd_link_relocatable (info)
14105 		    && ((elf_section_data (o)->this_hdr.sh_type
14106 			 == SHT_PREINIT_ARRAY)
14107 			|| (elf_section_data (o)->this_hdr.sh_type
14108 			    == SHT_INIT_ARRAY)
14109 			|| (elf_section_data (o)->this_hdr.sh_type
14110 			    == SHT_FINI_ARRAY)))
14111 		|| (elf_section_data (o)->this_hdr.sh_type == SHT_NOTE
14112 		    && elf_next_in_group (o) == NULL
14113 		    && elf_linked_to_section (o) == NULL)
14114 		|| ((elf_tdata (sub)->has_gnu_osabi & elf_gnu_osabi_retain)
14115 		    && (elf_section_flags (o) & SHF_GNU_RETAIN))))
14116 	  {
14117 	    if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
14118 	      return false;
14119 	  }
14120     }
14121 
14122   /* Allow the backend to mark additional target specific sections.  */
14123   bed->gc_mark_extra_sections (info, gc_mark_hook);
14124 
14125   /* ... and mark SEC_EXCLUDE for those that go.  */
14126   return elf_gc_sweep (abfd, info);
14127 }
14128 
14129 /* Called from check_relocs to record the existence of a VTINHERIT reloc.  */
14130 
14131 bool
bfd_elf_gc_record_vtinherit(bfd * abfd,asection * sec,struct elf_link_hash_entry * h,bfd_vma offset)14132 bfd_elf_gc_record_vtinherit (bfd *abfd,
14133 			     asection *sec,
14134 			     struct elf_link_hash_entry *h,
14135 			     bfd_vma offset)
14136 {
14137   struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
14138   struct elf_link_hash_entry **search, *child;
14139   size_t extsymcount;
14140   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14141 
14142   /* The sh_info field of the symtab header tells us where the
14143      external symbols start.  We don't care about the local symbols at
14144      this point.  */
14145   extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
14146   if (!elf_bad_symtab (abfd))
14147     extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
14148 
14149   sym_hashes = elf_sym_hashes (abfd);
14150   sym_hashes_end = sym_hashes + extsymcount;
14151 
14152   /* Hunt down the child symbol, which is in this section at the same
14153      offset as the relocation.  */
14154   for (search = sym_hashes; search != sym_hashes_end; ++search)
14155     {
14156       if ((child = *search) != NULL
14157 	  && (child->root.type == bfd_link_hash_defined
14158 	      || child->root.type == bfd_link_hash_defweak)
14159 	  && child->root.u.def.section == sec
14160 	  && child->root.u.def.value == offset)
14161 	goto win;
14162     }
14163 
14164   /* xgettext:c-format */
14165   _bfd_error_handler (_("%pB: %pA+%#" PRIx64 ": no symbol found for INHERIT"),
14166 		      abfd, sec, (uint64_t) offset);
14167   bfd_set_error (bfd_error_invalid_operation);
14168   return false;
14169 
14170  win:
14171   if (!child->u2.vtable)
14172     {
14173       child->u2.vtable = ((struct elf_link_virtual_table_entry *)
14174 			  bfd_zalloc (abfd, sizeof (*child->u2.vtable)));
14175       if (!child->u2.vtable)
14176 	return false;
14177     }
14178   if (!h)
14179     {
14180       /* This *should* only be the absolute section.  It could potentially
14181 	 be that someone has defined a non-global vtable though, which
14182 	 would be bad.  It isn't worth paging in the local symbols to be
14183 	 sure though; that case should simply be handled by the assembler.  */
14184 
14185       child->u2.vtable->parent = (struct elf_link_hash_entry *) -1;
14186     }
14187   else
14188     child->u2.vtable->parent = h;
14189 
14190   return true;
14191 }
14192 
14193 /* Called from check_relocs to record the existence of a VTENTRY reloc.  */
14194 
14195 bool
bfd_elf_gc_record_vtentry(bfd * abfd,asection * sec,struct elf_link_hash_entry * h,bfd_vma addend)14196 bfd_elf_gc_record_vtentry (bfd *abfd, asection *sec,
14197 			   struct elf_link_hash_entry *h,
14198 			   bfd_vma addend)
14199 {
14200   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14201   unsigned int log_file_align = bed->s->log_file_align;
14202 
14203   if (!h)
14204     {
14205       /* xgettext:c-format */
14206       _bfd_error_handler (_("%pB: section '%pA': corrupt VTENTRY entry"),
14207 			  abfd, sec);
14208       bfd_set_error (bfd_error_bad_value);
14209       return false;
14210     }
14211 
14212   if (!h->u2.vtable)
14213     {
14214       h->u2.vtable = ((struct elf_link_virtual_table_entry *)
14215 		      bfd_zalloc (abfd, sizeof (*h->u2.vtable)));
14216       if (!h->u2.vtable)
14217 	return false;
14218     }
14219 
14220   if (addend >= h->u2.vtable->size)
14221     {
14222       size_t size, bytes, file_align;
14223       bool *ptr = h->u2.vtable->used;
14224 
14225       /* While the symbol is undefined, we have to be prepared to handle
14226 	 a zero size.  */
14227       file_align = 1 << log_file_align;
14228       if (h->root.type == bfd_link_hash_undefined)
14229 	size = addend + file_align;
14230       else
14231 	{
14232 	  size = h->size;
14233 	  if (addend >= size)
14234 	    {
14235 	      /* Oops!  We've got a reference past the defined end of
14236 		 the table.  This is probably a bug -- shall we warn?  */
14237 	      size = addend + file_align;
14238 	    }
14239 	}
14240       size = (size + file_align - 1) & -file_align;
14241 
14242       /* Allocate one extra entry for use as a "done" flag for the
14243 	 consolidation pass.  */
14244       bytes = ((size >> log_file_align) + 1) * sizeof (bool);
14245 
14246       if (ptr)
14247 	{
14248 	  ptr = (bool *) bfd_realloc (ptr - 1, bytes);
14249 
14250 	  if (ptr != NULL)
14251 	    {
14252 	      size_t oldbytes;
14253 
14254 	      oldbytes = (((h->u2.vtable->size >> log_file_align) + 1)
14255 			  * sizeof (bool));
14256 	      memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
14257 	    }
14258 	}
14259       else
14260 	ptr = (bool *) bfd_zmalloc (bytes);
14261 
14262       if (ptr == NULL)
14263 	return false;
14264 
14265       /* And arrange for that done flag to be at index -1.  */
14266       h->u2.vtable->used = ptr + 1;
14267       h->u2.vtable->size = size;
14268     }
14269 
14270   h->u2.vtable->used[addend >> log_file_align] = true;
14271 
14272   return true;
14273 }
14274 
14275 /* Map an ELF section header flag to its corresponding string.  */
14276 typedef struct
14277 {
14278   char *flag_name;
14279   flagword flag_value;
14280 } elf_flags_to_name_table;
14281 
14282 static const elf_flags_to_name_table elf_flags_to_names [] =
14283 {
14284   { "SHF_WRITE", SHF_WRITE },
14285   { "SHF_ALLOC", SHF_ALLOC },
14286   { "SHF_EXECINSTR", SHF_EXECINSTR },
14287   { "SHF_MERGE", SHF_MERGE },
14288   { "SHF_STRINGS", SHF_STRINGS },
14289   { "SHF_INFO_LINK", SHF_INFO_LINK},
14290   { "SHF_LINK_ORDER", SHF_LINK_ORDER},
14291   { "SHF_OS_NONCONFORMING", SHF_OS_NONCONFORMING},
14292   { "SHF_GROUP", SHF_GROUP },
14293   { "SHF_TLS", SHF_TLS },
14294   { "SHF_MASKOS", SHF_MASKOS },
14295   { "SHF_EXCLUDE", SHF_EXCLUDE },
14296 };
14297 
14298 /* Returns TRUE if the section is to be included, otherwise FALSE.  */
14299 bool
bfd_elf_lookup_section_flags(struct bfd_link_info * info,struct flag_info * flaginfo,asection * section)14300 bfd_elf_lookup_section_flags (struct bfd_link_info *info,
14301 			      struct flag_info *flaginfo,
14302 			      asection *section)
14303 {
14304   const bfd_vma sh_flags = elf_section_flags (section);
14305 
14306   if (!flaginfo->flags_initialized)
14307     {
14308       bfd *obfd = info->output_bfd;
14309       const struct elf_backend_data *bed = get_elf_backend_data (obfd);
14310       struct flag_info_list *tf = flaginfo->flag_list;
14311       int with_hex = 0;
14312       int without_hex = 0;
14313 
14314       for (tf = flaginfo->flag_list; tf != NULL; tf = tf->next)
14315 	{
14316 	  unsigned i;
14317 	  flagword (*lookup) (char *);
14318 
14319 	  lookup = bed->elf_backend_lookup_section_flags_hook;
14320 	  if (lookup != NULL)
14321 	    {
14322 	      flagword hexval = (*lookup) ((char *) tf->name);
14323 
14324 	      if (hexval != 0)
14325 		{
14326 		  if (tf->with == with_flags)
14327 		    with_hex |= hexval;
14328 		  else if (tf->with == without_flags)
14329 		    without_hex |= hexval;
14330 		  tf->valid = true;
14331 		  continue;
14332 		}
14333 	    }
14334 	  for (i = 0; i < ARRAY_SIZE (elf_flags_to_names); ++i)
14335 	    {
14336 	      if (strcmp (tf->name, elf_flags_to_names[i].flag_name) == 0)
14337 		{
14338 		  if (tf->with == with_flags)
14339 		    with_hex |= elf_flags_to_names[i].flag_value;
14340 		  else if (tf->with == without_flags)
14341 		    without_hex |= elf_flags_to_names[i].flag_value;
14342 		  tf->valid = true;
14343 		  break;
14344 		}
14345 	    }
14346 	  if (!tf->valid)
14347 	    {
14348 	      info->callbacks->einfo
14349 		(_("unrecognized INPUT_SECTION_FLAG %s\n"), tf->name);
14350 	      return false;
14351 	    }
14352 	}
14353       flaginfo->flags_initialized = true;
14354       flaginfo->only_with_flags |= with_hex;
14355       flaginfo->not_with_flags |= without_hex;
14356     }
14357 
14358   if ((flaginfo->only_with_flags & sh_flags) != flaginfo->only_with_flags)
14359     return false;
14360 
14361   if ((flaginfo->not_with_flags & sh_flags) != 0)
14362     return false;
14363 
14364   return true;
14365 }
14366 
14367 struct alloc_got_off_arg {
14368   bfd_vma gotoff;
14369   struct bfd_link_info *info;
14370 };
14371 
14372 /* We need a special top-level link routine to convert got reference counts
14373    to real got offsets.  */
14374 
14375 static bool
elf_gc_allocate_got_offsets(struct elf_link_hash_entry * h,void * arg)14376 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
14377 {
14378   struct alloc_got_off_arg *gofarg = (struct alloc_got_off_arg *) arg;
14379   bfd *obfd = gofarg->info->output_bfd;
14380   const struct elf_backend_data *bed = get_elf_backend_data (obfd);
14381 
14382   if (h->got.refcount > 0)
14383     {
14384       h->got.offset = gofarg->gotoff;
14385       gofarg->gotoff += bed->got_elt_size (obfd, gofarg->info, h, NULL, 0);
14386     }
14387   else
14388     h->got.offset = (bfd_vma) -1;
14389 
14390   return true;
14391 }
14392 
14393 /* And an accompanying bit to work out final got entry offsets once
14394    we're done.  Should be called from final_link.  */
14395 
14396 bool
bfd_elf_gc_common_finalize_got_offsets(bfd * abfd,struct bfd_link_info * info)14397 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
14398 					struct bfd_link_info *info)
14399 {
14400   bfd *i;
14401   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14402   bfd_vma gotoff;
14403   struct alloc_got_off_arg gofarg;
14404 
14405   BFD_ASSERT (abfd == info->output_bfd);
14406 
14407   if (! is_elf_hash_table (info->hash))
14408     return false;
14409 
14410   /* The GOT offset is relative to the .got section, but the GOT header is
14411      put into the .got.plt section, if the backend uses it.  */
14412   if (bed->want_got_plt)
14413     gotoff = 0;
14414   else
14415     gotoff = bed->got_header_size;
14416 
14417   /* Do the local .got entries first.  */
14418   for (i = info->input_bfds; i; i = i->link.next)
14419     {
14420       bfd_signed_vma *local_got;
14421       size_t j, locsymcount;
14422       Elf_Internal_Shdr *symtab_hdr;
14423 
14424       if (bfd_get_flavour (i) != bfd_target_elf_flavour)
14425 	continue;
14426 
14427       local_got = elf_local_got_refcounts (i);
14428       if (!local_got)
14429 	continue;
14430 
14431       symtab_hdr = &elf_tdata (i)->symtab_hdr;
14432       if (elf_bad_symtab (i))
14433 	locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
14434       else
14435 	locsymcount = symtab_hdr->sh_info;
14436 
14437       for (j = 0; j < locsymcount; ++j)
14438 	{
14439 	  if (local_got[j] > 0)
14440 	    {
14441 	      local_got[j] = gotoff;
14442 	      gotoff += bed->got_elt_size (abfd, info, NULL, i, j);
14443 	    }
14444 	  else
14445 	    local_got[j] = (bfd_vma) -1;
14446 	}
14447     }
14448 
14449   /* Then the global .got entries.  .plt refcounts are handled by
14450      adjust_dynamic_symbol  */
14451   gofarg.gotoff = gotoff;
14452   gofarg.info = info;
14453   elf_link_hash_traverse (elf_hash_table (info),
14454 			  elf_gc_allocate_got_offsets,
14455 			  &gofarg);
14456   return true;
14457 }
14458 
14459 /* Many folk need no more in the way of final link than this, once
14460    got entry reference counting is enabled.  */
14461 
14462 bool
bfd_elf_gc_common_final_link(bfd * abfd,struct bfd_link_info * info)14463 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
14464 {
14465   if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
14466     return false;
14467 
14468   /* Invoke the regular ELF backend linker to do all the work.  */
14469   return bfd_elf_final_link (abfd, info);
14470 }
14471 
14472 bool
bfd_elf_reloc_symbol_deleted_p(bfd_vma offset,void * cookie)14473 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
14474 {
14475   struct elf_reloc_cookie *rcookie = (struct elf_reloc_cookie *) cookie;
14476 
14477   if (rcookie->bad_symtab)
14478     rcookie->rel = rcookie->rels;
14479 
14480   for (; rcookie->rel < rcookie->relend; rcookie->rel++)
14481     {
14482       unsigned long r_symndx;
14483 
14484       if (! rcookie->bad_symtab)
14485 	if (rcookie->rel->r_offset > offset)
14486 	  return false;
14487       if (rcookie->rel->r_offset != offset)
14488 	continue;
14489 
14490       r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
14491       if (r_symndx == STN_UNDEF)
14492 	return true;
14493 
14494       if (r_symndx >= rcookie->locsymcount
14495 	  || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
14496 	{
14497 	  struct elf_link_hash_entry *h;
14498 
14499 	  h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
14500 
14501 	  while (h->root.type == bfd_link_hash_indirect
14502 		 || h->root.type == bfd_link_hash_warning)
14503 	    h = (struct elf_link_hash_entry *) h->root.u.i.link;
14504 
14505 	  if ((h->root.type == bfd_link_hash_defined
14506 	       || h->root.type == bfd_link_hash_defweak)
14507 	      && (h->root.u.def.section->owner != rcookie->abfd
14508 		  || h->root.u.def.section->kept_section != NULL
14509 		  || discarded_section (h->root.u.def.section)))
14510 	    return true;
14511 	}
14512       else
14513 	{
14514 	  /* It's not a relocation against a global symbol,
14515 	     but it could be a relocation against a local
14516 	     symbol for a discarded section.  */
14517 	  asection *isec;
14518 	  Elf_Internal_Sym *isym;
14519 
14520 	  /* Need to: get the symbol; get the section.  */
14521 	  isym = &rcookie->locsyms[r_symndx];
14522 	  isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
14523 	  if (isec != NULL
14524 	      && (isec->kept_section != NULL
14525 		  || discarded_section (isec)))
14526 	    return true;
14527 	}
14528       return false;
14529     }
14530   return false;
14531 }
14532 
14533 /* Discard unneeded references to discarded sections.
14534    Returns -1 on error, 1 if any section's size was changed, 0 if
14535    nothing changed.  This function assumes that the relocations are in
14536    sorted order, which is true for all known assemblers.  */
14537 
14538 int
bfd_elf_discard_info(bfd * output_bfd,struct bfd_link_info * info)14539 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
14540 {
14541   struct elf_reloc_cookie cookie;
14542   asection *o;
14543   bfd *abfd;
14544   int changed = 0;
14545 
14546   if (info->traditional_format
14547       || !is_elf_hash_table (info->hash))
14548     return 0;
14549 
14550   o = bfd_get_section_by_name (output_bfd, ".stab");
14551   if (o != NULL)
14552     {
14553       asection *i;
14554 
14555       for (i = o->map_head.s; i != NULL; i = i->map_head.s)
14556 	{
14557 	  if (i->size == 0
14558 	      || i->reloc_count == 0
14559 	      || i->sec_info_type != SEC_INFO_TYPE_STABS)
14560 	    continue;
14561 
14562 	  abfd = i->owner;
14563 	  if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
14564 	    continue;
14565 
14566 	  if (!init_reloc_cookie_for_section (&cookie, info, i))
14567 	    return -1;
14568 
14569 	  if (_bfd_discard_section_stabs (abfd, i,
14570 					  elf_section_data (i)->sec_info,
14571 					  bfd_elf_reloc_symbol_deleted_p,
14572 					  &cookie))
14573 	    changed = 1;
14574 
14575 	  fini_reloc_cookie_for_section (&cookie, i);
14576 	}
14577     }
14578 
14579   o = NULL;
14580   if (info->eh_frame_hdr_type != COMPACT_EH_HDR)
14581     o = bfd_get_section_by_name (output_bfd, ".eh_frame");
14582   if (o != NULL)
14583     {
14584       asection *i;
14585       int eh_changed = 0;
14586       unsigned int eh_alignment;  /* Octets.  */
14587 
14588       for (i = o->map_head.s; i != NULL; i = i->map_head.s)
14589 	{
14590 	  if (i->size == 0)
14591 	    continue;
14592 
14593 	  abfd = i->owner;
14594 	  if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
14595 	    continue;
14596 
14597 	  if (!init_reloc_cookie_for_section (&cookie, info, i))
14598 	    return -1;
14599 
14600 	  _bfd_elf_parse_eh_frame (abfd, info, i, &cookie);
14601 	  if (_bfd_elf_discard_section_eh_frame (abfd, info, i,
14602 						 bfd_elf_reloc_symbol_deleted_p,
14603 						 &cookie))
14604 	    {
14605 	      eh_changed = 1;
14606 	      if (i->size != i->rawsize)
14607 		changed = 1;
14608 	    }
14609 
14610 	  fini_reloc_cookie_for_section (&cookie, i);
14611 	}
14612 
14613       eh_alignment = ((1 << o->alignment_power)
14614 		      * bfd_octets_per_byte (output_bfd, o));
14615       /* Skip over zero terminator, and prevent empty sections from
14616 	 adding alignment padding at the end.  */
14617       for (i = o->map_tail.s; i != NULL; i = i->map_tail.s)
14618 	if (i->size == 0)
14619 	  i->flags |= SEC_EXCLUDE;
14620 	else if (i->size > 4)
14621 	  break;
14622       /* The last non-empty eh_frame section doesn't need padding.  */
14623       if (i != NULL)
14624 	i = i->map_tail.s;
14625       /* Any prior sections must pad the last FDE out to the output
14626 	 section alignment.  Otherwise we might have zero padding
14627 	 between sections, which would be seen as a terminator.  */
14628       for (; i != NULL; i = i->map_tail.s)
14629 	if (i->size == 4)
14630 	  /* All but the last zero terminator should have been removed.  */
14631 	  BFD_FAIL ();
14632 	else
14633 	  {
14634 	    bfd_size_type size
14635 	      = (i->size + eh_alignment - 1) & -eh_alignment;
14636 	    if (i->size != size)
14637 	      {
14638 		i->size = size;
14639 		changed = 1;
14640 		eh_changed = 1;
14641 	      }
14642 	  }
14643       if (eh_changed)
14644 	elf_link_hash_traverse (elf_hash_table (info),
14645 				_bfd_elf_adjust_eh_frame_global_symbol, NULL);
14646     }
14647 
14648   for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link.next)
14649     {
14650       const struct elf_backend_data *bed;
14651       asection *s;
14652 
14653       if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
14654 	continue;
14655       s = abfd->sections;
14656       if (s == NULL || s->sec_info_type == SEC_INFO_TYPE_JUST_SYMS)
14657 	continue;
14658 
14659       bed = get_elf_backend_data (abfd);
14660 
14661       if (bed->elf_backend_discard_info != NULL)
14662 	{
14663 	  if (!init_reloc_cookie (&cookie, info, abfd))
14664 	    return -1;
14665 
14666 	  if ((*bed->elf_backend_discard_info) (abfd, &cookie, info))
14667 	    changed = 1;
14668 
14669 	  fini_reloc_cookie (&cookie, abfd);
14670 	}
14671     }
14672 
14673   if (info->eh_frame_hdr_type == COMPACT_EH_HDR)
14674     _bfd_elf_end_eh_frame_parsing (info);
14675 
14676   if (info->eh_frame_hdr_type
14677       && !bfd_link_relocatable (info)
14678       && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
14679     changed = 1;
14680 
14681   return changed;
14682 }
14683 
14684 bool
_bfd_elf_section_already_linked(bfd * abfd,asection * sec,struct bfd_link_info * info)14685 _bfd_elf_section_already_linked (bfd *abfd,
14686 				 asection *sec,
14687 				 struct bfd_link_info *info)
14688 {
14689   flagword flags;
14690   const char *name, *key;
14691   struct bfd_section_already_linked *l;
14692   struct bfd_section_already_linked_hash_entry *already_linked_list;
14693 
14694   if (sec->output_section == bfd_abs_section_ptr)
14695     return false;
14696 
14697   flags = sec->flags;
14698 
14699   /* Return if it isn't a linkonce section.  A comdat group section
14700      also has SEC_LINK_ONCE set.  */
14701   if ((flags & SEC_LINK_ONCE) == 0)
14702     return false;
14703 
14704   /* Don't put group member sections on our list of already linked
14705      sections.  They are handled as a group via their group section.  */
14706   if (elf_sec_group (sec) != NULL)
14707     return false;
14708 
14709   /* For a SHT_GROUP section, use the group signature as the key.  */
14710   name = sec->name;
14711   if ((flags & SEC_GROUP) != 0
14712       && elf_next_in_group (sec) != NULL
14713       && elf_group_name (elf_next_in_group (sec)) != NULL)
14714     key = elf_group_name (elf_next_in_group (sec));
14715   else
14716     {
14717       /* Otherwise we should have a .gnu.linkonce.<type>.<key> section.  */
14718       if (startswith (name, ".gnu.linkonce.")
14719 	  && (key = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
14720 	key++;
14721       else
14722 	/* Must be a user linkonce section that doesn't follow gcc's
14723 	   naming convention.  In this case we won't be matching
14724 	   single member groups.  */
14725 	key = name;
14726     }
14727 
14728   already_linked_list = bfd_section_already_linked_table_lookup (key);
14729 
14730   for (l = already_linked_list->entry; l != NULL; l = l->next)
14731     {
14732       /* We may have 2 different types of sections on the list: group
14733 	 sections with a signature of <key> (<key> is some string),
14734 	 and linkonce sections named .gnu.linkonce.<type>.<key>.
14735 	 Match like sections.  LTO plugin sections are an exception.
14736 	 They are always named .gnu.linkonce.t.<key> and match either
14737 	 type of section.  */
14738       if (((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
14739 	   && ((flags & SEC_GROUP) != 0
14740 	       || strcmp (name, l->sec->name) == 0))
14741 	  || (l->sec->owner->flags & BFD_PLUGIN) != 0
14742 	  || (sec->owner->flags & BFD_PLUGIN) != 0)
14743 	{
14744 	  /* The section has already been linked.  See if we should
14745 	     issue a warning.  */
14746 	  if (!_bfd_handle_already_linked (sec, l, info))
14747 	    return false;
14748 
14749 	  if (flags & SEC_GROUP)
14750 	    {
14751 	      asection *first = elf_next_in_group (sec);
14752 	      asection *s = first;
14753 
14754 	      while (s != NULL)
14755 		{
14756 		  s->output_section = bfd_abs_section_ptr;
14757 		  /* Record which group discards it.  */
14758 		  s->kept_section = l->sec;
14759 		  s = elf_next_in_group (s);
14760 		  /* These lists are circular.  */
14761 		  if (s == first)
14762 		    break;
14763 		}
14764 	    }
14765 
14766 	  return true;
14767 	}
14768     }
14769 
14770   /* A single member comdat group section may be discarded by a
14771      linkonce section and vice versa.  */
14772   if ((flags & SEC_GROUP) != 0)
14773     {
14774       asection *first = elf_next_in_group (sec);
14775 
14776       if (first != NULL && elf_next_in_group (first) == first)
14777 	/* Check this single member group against linkonce sections.  */
14778 	for (l = already_linked_list->entry; l != NULL; l = l->next)
14779 	  if ((l->sec->flags & SEC_GROUP) == 0
14780 	      && bfd_elf_match_symbols_in_sections (l->sec, first, info))
14781 	    {
14782 	      first->output_section = bfd_abs_section_ptr;
14783 	      first->kept_section = l->sec;
14784 	      sec->output_section = bfd_abs_section_ptr;
14785 	      break;
14786 	    }
14787     }
14788   else
14789     /* Check this linkonce section against single member groups.  */
14790     for (l = already_linked_list->entry; l != NULL; l = l->next)
14791       if (l->sec->flags & SEC_GROUP)
14792 	{
14793 	  asection *first = elf_next_in_group (l->sec);
14794 
14795 	  if (first != NULL
14796 	      && elf_next_in_group (first) == first
14797 	      && bfd_elf_match_symbols_in_sections (first, sec, info))
14798 	    {
14799 	      sec->output_section = bfd_abs_section_ptr;
14800 	      sec->kept_section = first;
14801 	      break;
14802 	    }
14803 	}
14804 
14805   /* Do not complain on unresolved relocations in `.gnu.linkonce.r.F'
14806      referencing its discarded `.gnu.linkonce.t.F' counterpart - g++-3.4
14807      specific as g++-4.x is using COMDAT groups (without the `.gnu.linkonce'
14808      prefix) instead.  `.gnu.linkonce.r.*' were the `.rodata' part of its
14809      matching `.gnu.linkonce.t.*'.  If `.gnu.linkonce.r.F' is not discarded
14810      but its `.gnu.linkonce.t.F' is discarded means we chose one-only
14811      `.gnu.linkonce.t.F' section from a different bfd not requiring any
14812      `.gnu.linkonce.r.F'.  Thus `.gnu.linkonce.r.F' should be discarded.
14813      The reverse order cannot happen as there is never a bfd with only the
14814      `.gnu.linkonce.r.F' section.  The order of sections in a bfd does not
14815      matter as here were are looking only for cross-bfd sections.  */
14816 
14817   if ((flags & SEC_GROUP) == 0 && startswith (name, ".gnu.linkonce.r."))
14818     for (l = already_linked_list->entry; l != NULL; l = l->next)
14819       if ((l->sec->flags & SEC_GROUP) == 0
14820 	  && startswith (l->sec->name, ".gnu.linkonce.t."))
14821 	{
14822 	  if (abfd != l->sec->owner)
14823 	    sec->output_section = bfd_abs_section_ptr;
14824 	  break;
14825 	}
14826 
14827   /* This is the first section with this name.  Record it.  */
14828   if (!bfd_section_already_linked_table_insert (already_linked_list, sec))
14829     info->callbacks->einfo (_("%F%P: already_linked_table: %E\n"));
14830   return sec->output_section == bfd_abs_section_ptr;
14831 }
14832 
14833 bool
_bfd_elf_common_definition(Elf_Internal_Sym * sym)14834 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
14835 {
14836   return sym->st_shndx == SHN_COMMON;
14837 }
14838 
14839 unsigned int
_bfd_elf_common_section_index(asection * sec ATTRIBUTE_UNUSED)14840 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
14841 {
14842   return SHN_COMMON;
14843 }
14844 
14845 asection *
_bfd_elf_common_section(asection * sec ATTRIBUTE_UNUSED)14846 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
14847 {
14848   return bfd_com_section_ptr;
14849 }
14850 
14851 bfd_vma
_bfd_elf_default_got_elt_size(bfd * abfd,struct bfd_link_info * info ATTRIBUTE_UNUSED,struct elf_link_hash_entry * h ATTRIBUTE_UNUSED,bfd * ibfd ATTRIBUTE_UNUSED,unsigned long symndx ATTRIBUTE_UNUSED)14852 _bfd_elf_default_got_elt_size (bfd *abfd,
14853 			       struct bfd_link_info *info ATTRIBUTE_UNUSED,
14854 			       struct elf_link_hash_entry *h ATTRIBUTE_UNUSED,
14855 			       bfd *ibfd ATTRIBUTE_UNUSED,
14856 			       unsigned long symndx ATTRIBUTE_UNUSED)
14857 {
14858   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14859   return bed->s->arch_size / 8;
14860 }
14861 
14862 /* Routines to support the creation of dynamic relocs.  */
14863 
14864 /* Returns the name of the dynamic reloc section associated with SEC.  */
14865 
14866 static const char *
get_dynamic_reloc_section_name(bfd * abfd,asection * sec,bool is_rela)14867 get_dynamic_reloc_section_name (bfd *       abfd,
14868 				asection *  sec,
14869 				bool is_rela)
14870 {
14871   char *name;
14872   const char *old_name = bfd_section_name (sec);
14873   const char *prefix = is_rela ? ".rela" : ".rel";
14874 
14875   if (old_name == NULL)
14876     return NULL;
14877 
14878   name = bfd_alloc (abfd, strlen (prefix) + strlen (old_name) + 1);
14879   sprintf (name, "%s%s", prefix, old_name);
14880 
14881   return name;
14882 }
14883 
14884 /* Returns the dynamic reloc section associated with SEC.
14885    If necessary compute the name of the dynamic reloc section based
14886    on SEC's name (looked up in ABFD's string table) and the setting
14887    of IS_RELA.  */
14888 
14889 asection *
_bfd_elf_get_dynamic_reloc_section(bfd * abfd,asection * sec,bool is_rela)14890 _bfd_elf_get_dynamic_reloc_section (bfd *abfd,
14891 				    asection *sec,
14892 				    bool is_rela)
14893 {
14894   asection *reloc_sec = elf_section_data (sec)->sreloc;
14895 
14896   if (reloc_sec == NULL)
14897     {
14898       const char *name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
14899 
14900       if (name != NULL)
14901 	{
14902 	  reloc_sec = bfd_get_linker_section (abfd, name);
14903 
14904 	  if (reloc_sec != NULL)
14905 	    elf_section_data (sec)->sreloc = reloc_sec;
14906 	}
14907     }
14908 
14909   return reloc_sec;
14910 }
14911 
14912 /* Returns the dynamic reloc section associated with SEC.  If the
14913    section does not exist it is created and attached to the DYNOBJ
14914    bfd and stored in the SRELOC field of SEC's elf_section_data
14915    structure.
14916 
14917    ALIGNMENT is the alignment for the newly created section and
14918    IS_RELA defines whether the name should be .rela.<SEC's name>
14919    or .rel.<SEC's name>.  The section name is looked up in the
14920    string table associated with ABFD.  */
14921 
14922 asection *
_bfd_elf_make_dynamic_reloc_section(asection * sec,bfd * dynobj,unsigned int alignment,bfd * abfd,bool is_rela)14923 _bfd_elf_make_dynamic_reloc_section (asection *sec,
14924 				     bfd *dynobj,
14925 				     unsigned int alignment,
14926 				     bfd *abfd,
14927 				     bool is_rela)
14928 {
14929   asection * reloc_sec = elf_section_data (sec)->sreloc;
14930 
14931   if (reloc_sec == NULL)
14932     {
14933       const char * name = get_dynamic_reloc_section_name (abfd, sec, is_rela);
14934 
14935       if (name == NULL)
14936 	return NULL;
14937 
14938       reloc_sec = bfd_get_linker_section (dynobj, name);
14939 
14940       if (reloc_sec == NULL)
14941 	{
14942 	  flagword flags = (SEC_HAS_CONTENTS | SEC_READONLY
14943 			    | SEC_IN_MEMORY | SEC_LINKER_CREATED);
14944 	  if ((sec->flags & SEC_ALLOC) != 0)
14945 	    flags |= SEC_ALLOC | SEC_LOAD;
14946 
14947 	  reloc_sec = bfd_make_section_anyway_with_flags (dynobj, name, flags);
14948 	  if (reloc_sec != NULL)
14949 	    {
14950 	      /* _bfd_elf_get_sec_type_attr chooses a section type by
14951 		 name.  Override as it may be wrong, eg. for a user
14952 		 section named "auto" we'll get ".relauto" which is
14953 		 seen to be a .rela section.  */
14954 	      elf_section_type (reloc_sec) = is_rela ? SHT_RELA : SHT_REL;
14955 	      if (!bfd_set_section_alignment (reloc_sec, alignment))
14956 		reloc_sec = NULL;
14957 	    }
14958 	}
14959 
14960       elf_section_data (sec)->sreloc = reloc_sec;
14961     }
14962 
14963   return reloc_sec;
14964 }
14965 
14966 /* Copy the ELF symbol type and other attributes for a linker script
14967    assignment from HSRC to HDEST.  Generally this should be treated as
14968    if we found a strong non-dynamic definition for HDEST (except that
14969    ld ignores multiple definition errors).  */
14970 void
_bfd_elf_copy_link_hash_symbol_type(bfd * abfd,struct bfd_link_hash_entry * hdest,struct bfd_link_hash_entry * hsrc)14971 _bfd_elf_copy_link_hash_symbol_type (bfd *abfd,
14972 				     struct bfd_link_hash_entry *hdest,
14973 				     struct bfd_link_hash_entry *hsrc)
14974 {
14975   struct elf_link_hash_entry *ehdest = (struct elf_link_hash_entry *) hdest;
14976   struct elf_link_hash_entry *ehsrc = (struct elf_link_hash_entry *) hsrc;
14977   Elf_Internal_Sym isym;
14978 
14979   ehdest->type = ehsrc->type;
14980   ehdest->target_internal = ehsrc->target_internal;
14981 
14982   isym.st_other = ehsrc->other;
14983   elf_merge_st_other (abfd, ehdest, isym.st_other, NULL, true, false);
14984 }
14985 
14986 /* Append a RELA relocation REL to section S in BFD.  */
14987 
14988 void
elf_append_rela(bfd * abfd,asection * s,Elf_Internal_Rela * rel)14989 elf_append_rela (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
14990 {
14991   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
14992   bfd_byte *loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rela);
14993   BFD_ASSERT (loc + bed->s->sizeof_rela <= s->contents + s->size);
14994   bed->s->swap_reloca_out (abfd, rel, loc);
14995 }
14996 
14997 /* Append a REL relocation REL to section S in BFD.  */
14998 
14999 void
elf_append_rel(bfd * abfd,asection * s,Elf_Internal_Rela * rel)15000 elf_append_rel (bfd *abfd, asection *s, Elf_Internal_Rela *rel)
15001 {
15002   const struct elf_backend_data *bed = get_elf_backend_data (abfd);
15003   bfd_byte *loc = s->contents + (s->reloc_count++ * bed->s->sizeof_rel);
15004   BFD_ASSERT (loc + bed->s->sizeof_rel <= s->contents + s->size);
15005   bed->s->swap_reloc_out (abfd, rel, loc);
15006 }
15007 
15008 /* Define __start, __stop, .startof. or .sizeof. symbol.  */
15009 
15010 struct bfd_link_hash_entry *
bfd_elf_define_start_stop(struct bfd_link_info * info,const char * symbol,asection * sec)15011 bfd_elf_define_start_stop (struct bfd_link_info *info,
15012 			   const char *symbol, asection *sec)
15013 {
15014   struct elf_link_hash_entry *h;
15015 
15016   h = elf_link_hash_lookup (elf_hash_table (info), symbol,
15017 			    false, false, true);
15018   /* NB: Common symbols will be turned into definition later.  */
15019   if (h != NULL
15020       && !h->root.ldscript_def
15021       && (h->root.type == bfd_link_hash_undefined
15022 	  || h->root.type == bfd_link_hash_undefweak
15023 	  || ((h->ref_regular || h->def_dynamic)
15024 	      && !h->def_regular
15025 	      && h->root.type != bfd_link_hash_common)))
15026     {
15027       bool was_dynamic = h->ref_dynamic || h->def_dynamic;
15028       h->verinfo.verdef = NULL;
15029       h->root.type = bfd_link_hash_defined;
15030       h->root.u.def.section = sec;
15031       h->root.u.def.value = 0;
15032       h->def_regular = 1;
15033       h->def_dynamic = 0;
15034       h->start_stop = 1;
15035       h->u2.start_stop_section = sec;
15036       if (symbol[0] == '.')
15037 	{
15038 	  /* .startof. and .sizeof. symbols are local.  */
15039 	  const struct elf_backend_data *bed;
15040 	  bed = get_elf_backend_data (info->output_bfd);
15041 	  (*bed->elf_backend_hide_symbol) (info, h, true);
15042 	}
15043       else
15044 	{
15045 	  if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
15046 	    h->other = ((h->other & ~ELF_ST_VISIBILITY (-1))
15047 			| info->start_stop_visibility);
15048 	  if (was_dynamic)
15049 	    bfd_elf_link_record_dynamic_symbol (info, h);
15050 	}
15051       return &h->root;
15052     }
15053   return NULL;
15054 }
15055 
15056 /* Find dynamic relocs for H that apply to read-only sections.  */
15057 
15058 asection *
_bfd_elf_readonly_dynrelocs(struct elf_link_hash_entry * h)15059 _bfd_elf_readonly_dynrelocs (struct elf_link_hash_entry *h)
15060 {
15061   struct elf_dyn_relocs *p;
15062 
15063   for (p = h->dyn_relocs; p != NULL; p = p->next)
15064     {
15065       asection *s = p->sec->output_section;
15066 
15067       if (s != NULL && (s->flags & SEC_READONLY) != 0)
15068 	return p->sec;
15069     }
15070   return NULL;
15071 }
15072 
15073 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
15074    read-only sections.  */
15075 
15076 bool
_bfd_elf_maybe_set_textrel(struct elf_link_hash_entry * h,void * inf)15077 _bfd_elf_maybe_set_textrel (struct elf_link_hash_entry *h, void *inf)
15078 {
15079   asection *sec;
15080 
15081   if (h->root.type == bfd_link_hash_indirect)
15082     return true;
15083 
15084   sec = _bfd_elf_readonly_dynrelocs (h);
15085   if (sec != NULL)
15086     {
15087       struct bfd_link_info *info = (struct bfd_link_info *) inf;
15088 
15089       info->flags |= DF_TEXTREL;
15090       /* xgettext:c-format */
15091       info->callbacks->minfo (_("%pB: dynamic relocation against `%pT' "
15092 				"in read-only section `%pA'\n"),
15093 			      sec->owner, h->root.root.string, sec);
15094 
15095       if (bfd_link_textrel_check (info))
15096 	/* xgettext:c-format */
15097 	info->callbacks->einfo (_("%P: %pB: warning: relocation against `%s' "
15098 				  "in read-only section `%pA'\n"),
15099 				sec->owner, h->root.root.string, sec);
15100 
15101       /* Not an error, just cut short the traversal.  */
15102       return false;
15103     }
15104   return true;
15105 }
15106 
15107 /* Add dynamic tags.  */
15108 
15109 bool
_bfd_elf_add_dynamic_tags(bfd * output_bfd,struct bfd_link_info * info,bool need_dynamic_reloc)15110 _bfd_elf_add_dynamic_tags (bfd *output_bfd, struct bfd_link_info *info,
15111 			   bool need_dynamic_reloc)
15112 {
15113   struct elf_link_hash_table *htab = elf_hash_table (info);
15114 
15115   if (htab->dynamic_sections_created)
15116     {
15117       /* Add some entries to the .dynamic section.  We fill in the
15118 	 values later, in finish_dynamic_sections, but we must add
15119 	 the entries now so that we get the correct size for the
15120 	 .dynamic section.  The DT_DEBUG entry is filled in by the
15121 	 dynamic linker and used by the debugger.  */
15122 #define add_dynamic_entry(TAG, VAL) \
15123   _bfd_elf_add_dynamic_entry (info, TAG, VAL)
15124 
15125       const struct elf_backend_data *bed
15126 	= get_elf_backend_data (output_bfd);
15127 
15128       if (bfd_link_executable (info))
15129 	{
15130 	  if (!add_dynamic_entry (DT_DEBUG, 0))
15131 	    return false;
15132 	}
15133 
15134       if (htab->dt_pltgot_required || htab->splt->size != 0)
15135 	{
15136 	  /* DT_PLTGOT is used by prelink even if there is no PLT
15137 	     relocation.  */
15138 	  if (!add_dynamic_entry (DT_PLTGOT, 0))
15139 	    return false;
15140 	}
15141 
15142       if (htab->dt_jmprel_required || htab->srelplt->size != 0)
15143 	{
15144 	  if (!add_dynamic_entry (DT_PLTRELSZ, 0)
15145 	      || !add_dynamic_entry (DT_PLTREL,
15146 				     (bed->rela_plts_and_copies_p
15147 				      ? DT_RELA : DT_REL))
15148 	      || !add_dynamic_entry (DT_JMPREL, 0))
15149 	    return false;
15150 	}
15151 
15152       if (htab->tlsdesc_plt
15153 	  && (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
15154 	      || !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
15155 	return false;
15156 
15157       if (need_dynamic_reloc)
15158 	{
15159 	  if (bed->rela_plts_and_copies_p)
15160 	    {
15161 	      if (!add_dynamic_entry (DT_RELA, 0)
15162 		  || !add_dynamic_entry (DT_RELASZ, 0)
15163 		  || !add_dynamic_entry (DT_RELAENT,
15164 					 bed->s->sizeof_rela))
15165 		return false;
15166 	    }
15167 	  else
15168 	    {
15169 	      if (!add_dynamic_entry (DT_REL, 0)
15170 		  || !add_dynamic_entry (DT_RELSZ, 0)
15171 		  || !add_dynamic_entry (DT_RELENT,
15172 					 bed->s->sizeof_rel))
15173 		return false;
15174 	    }
15175 
15176 	  /* If any dynamic relocs apply to a read-only section,
15177 	     then we need a DT_TEXTREL entry.  */
15178 	  if ((info->flags & DF_TEXTREL) == 0)
15179 	    elf_link_hash_traverse (htab, _bfd_elf_maybe_set_textrel,
15180 				    info);
15181 
15182 	  if ((info->flags & DF_TEXTREL) != 0)
15183 	    {
15184 	      if (htab->ifunc_resolvers)
15185 		info->callbacks->einfo
15186 		  (_("%P: warning: GNU indirect functions with DT_TEXTREL "
15187 		     "may result in a segfault at runtime; recompile with %s\n"),
15188 		   bfd_link_dll (info) ? "-fPIC" : "-fPIE");
15189 
15190 	      if (!add_dynamic_entry (DT_TEXTREL, 0))
15191 		return false;
15192 	    }
15193 	}
15194     }
15195 #undef add_dynamic_entry
15196 
15197   return true;
15198 }
15199