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[deliverable/binutils-gdb.git] / bfd / elf32-i386.c
1 /* Intel 80386/80486-specific support for 32-bit ELF
2 Copyright 1993, 1994, 1995, 1996 Free Software Foundation, Inc.
3
4 This file is part of BFD, the Binary File Descriptor library.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
19
20 #include "bfd.h"
21 #include "sysdep.h"
22 #include "bfdlink.h"
23 #include "libbfd.h"
24 #include "elf-bfd.h"
25
26 static reloc_howto_type *elf_i386_reloc_type_lookup
27 PARAMS ((bfd *, bfd_reloc_code_real_type));
28 static void elf_i386_info_to_howto
29 PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
30 static void elf_i386_info_to_howto_rel
31 PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
32 static boolean elf_i386_check_relocs
33 PARAMS ((bfd *, struct bfd_link_info *, asection *,
34 const Elf_Internal_Rela *));
35 static boolean elf_i386_adjust_dynamic_symbol
36 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
37 static boolean elf_i386_size_dynamic_sections
38 PARAMS ((bfd *, struct bfd_link_info *));
39 static boolean elf_i386_relocate_section
40 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
41 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
42 static boolean elf_i386_finish_dynamic_symbol
43 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
44 Elf_Internal_Sym *));
45 static boolean elf_i386_finish_dynamic_sections
46 PARAMS ((bfd *, struct bfd_link_info *));
47
48 #define USE_REL 1 /* 386 uses REL relocations instead of RELA */
49
50 enum reloc_type
51 {
52 R_386_NONE = 0,
53 R_386_32,
54 R_386_PC32,
55 R_386_GOT32,
56 R_386_PLT32,
57 R_386_COPY,
58 R_386_GLOB_DAT,
59 R_386_JUMP_SLOT,
60 R_386_RELATIVE,
61 R_386_GOTOFF,
62 R_386_GOTPC,
63 R_386_max
64 };
65
66 #if 0
67 static CONST char *CONST reloc_type_names[] =
68 {
69 "R_386_NONE",
70 "R_386_32",
71 "R_386_PC32",
72 "R_386_GOT32",
73 "R_386_PLT32",
74 "R_386_COPY",
75 "R_386_GLOB_DAT",
76 "R_386_JUMP_SLOT",
77 "R_386_RELATIVE",
78 "R_386_GOTOFF",
79 "R_386_GOTPC",
80 };
81 #endif
82
83 static reloc_howto_type elf_howto_table[]=
84 {
85 HOWTO(R_386_NONE, 0,0, 0,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_NONE", true,0x00000000,0x00000000,false),
86 HOWTO(R_386_32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_32", true,0xffffffff,0xffffffff,false),
87 HOWTO(R_386_PC32, 0,2,32,true, 0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PC32", true,0xffffffff,0xffffffff,true),
88 HOWTO(R_386_GOT32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOT32", true,0xffffffff,0xffffffff,false),
89 HOWTO(R_386_PLT32, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PLT32", true,0xffffffff,0xffffffff,true),
90 HOWTO(R_386_COPY, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_COPY", true,0xffffffff,0xffffffff,false),
91 HOWTO(R_386_GLOB_DAT, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GLOB_DAT", true,0xffffffff,0xffffffff,false),
92 HOWTO(R_386_JUMP_SLOT, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_JUMP_SLOT",true,0xffffffff,0xffffffff,false),
93 HOWTO(R_386_RELATIVE, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_RELATIVE", true,0xffffffff,0xffffffff,false),
94 HOWTO(R_386_GOTOFF, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTOFF", true,0xffffffff,0xffffffff,false),
95 HOWTO(R_386_GOTPC, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTPC", true,0xffffffff,0xffffffff,true),
96 };
97
98 #ifdef DEBUG_GEN_RELOC
99 #define TRACE(str) fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
100 #else
101 #define TRACE(str)
102 #endif
103
104 static reloc_howto_type *
105 elf_i386_reloc_type_lookup (abfd, code)
106 bfd *abfd;
107 bfd_reloc_code_real_type code;
108 {
109 switch (code)
110 {
111 case BFD_RELOC_NONE:
112 TRACE ("BFD_RELOC_NONE");
113 return &elf_howto_table[ (int)R_386_NONE ];
114
115 case BFD_RELOC_32:
116 TRACE ("BFD_RELOC_32");
117 return &elf_howto_table[ (int)R_386_32 ];
118
119 case BFD_RELOC_32_PCREL:
120 TRACE ("BFD_RELOC_PC32");
121 return &elf_howto_table[ (int)R_386_PC32 ];
122
123 case BFD_RELOC_386_GOT32:
124 TRACE ("BFD_RELOC_386_GOT32");
125 return &elf_howto_table[ (int)R_386_GOT32 ];
126
127 case BFD_RELOC_386_PLT32:
128 TRACE ("BFD_RELOC_386_PLT32");
129 return &elf_howto_table[ (int)R_386_PLT32 ];
130
131 case BFD_RELOC_386_COPY:
132 TRACE ("BFD_RELOC_386_COPY");
133 return &elf_howto_table[ (int)R_386_COPY ];
134
135 case BFD_RELOC_386_GLOB_DAT:
136 TRACE ("BFD_RELOC_386_GLOB_DAT");
137 return &elf_howto_table[ (int)R_386_GLOB_DAT ];
138
139 case BFD_RELOC_386_JUMP_SLOT:
140 TRACE ("BFD_RELOC_386_JUMP_SLOT");
141 return &elf_howto_table[ (int)R_386_JUMP_SLOT ];
142
143 case BFD_RELOC_386_RELATIVE:
144 TRACE ("BFD_RELOC_386_RELATIVE");
145 return &elf_howto_table[ (int)R_386_RELATIVE ];
146
147 case BFD_RELOC_386_GOTOFF:
148 TRACE ("BFD_RELOC_386_GOTOFF");
149 return &elf_howto_table[ (int)R_386_GOTOFF ];
150
151 case BFD_RELOC_386_GOTPC:
152 TRACE ("BFD_RELOC_386_GOTPC");
153 return &elf_howto_table[ (int)R_386_GOTPC ];
154
155 default:
156 break;
157 }
158
159 TRACE ("Unknown");
160 return 0;
161 }
162
163 static void
164 elf_i386_info_to_howto (abfd, cache_ptr, dst)
165 bfd *abfd;
166 arelent *cache_ptr;
167 Elf32_Internal_Rela *dst;
168 {
169 BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
170
171 cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
172 }
173
174 static void
175 elf_i386_info_to_howto_rel (abfd, cache_ptr, dst)
176 bfd *abfd;
177 arelent *cache_ptr;
178 Elf32_Internal_Rel *dst;
179 {
180 BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
181
182 cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
183 }
184 \f
185 /* Functions for the i386 ELF linker. */
186
187 /* The name of the dynamic interpreter. This is put in the .interp
188 section. */
189
190 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
191
192 /* The size in bytes of an entry in the procedure linkage table. */
193
194 #define PLT_ENTRY_SIZE 16
195
196 /* The first entry in an absolute procedure linkage table looks like
197 this. See the SVR4 ABI i386 supplement to see how this works. */
198
199 static const bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
200 {
201 0xff, 0x35, /* pushl contents of address */
202 0, 0, 0, 0, /* replaced with address of .got + 4. */
203 0xff, 0x25, /* jmp indirect */
204 0, 0, 0, 0, /* replaced with address of .got + 8. */
205 0, 0, 0, 0 /* pad out to 16 bytes. */
206 };
207
208 /* Subsequent entries in an absolute procedure linkage table look like
209 this. */
210
211 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
212 {
213 0xff, 0x25, /* jmp indirect */
214 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
215 0x68, /* pushl immediate */
216 0, 0, 0, 0, /* replaced with offset into relocation table. */
217 0xe9, /* jmp relative */
218 0, 0, 0, 0 /* replaced with offset to start of .plt. */
219 };
220
221 /* The first entry in a PIC procedure linkage table look like this. */
222
223 static const bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
224 {
225 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
226 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
227 0, 0, 0, 0 /* pad out to 16 bytes. */
228 };
229
230 /* Subsequent entries in a PIC procedure linkage table look like this. */
231
232 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
233 {
234 0xff, 0xa3, /* jmp *offset(%ebx) */
235 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
236 0x68, /* pushl immediate */
237 0, 0, 0, 0, /* replaced with offset into relocation table. */
238 0xe9, /* jmp relative */
239 0, 0, 0, 0 /* replaced with offset to start of .plt. */
240 };
241
242 /* Look through the relocs for a section during the first phase, and
243 allocate space in the global offset table or procedure linkage
244 table. */
245
246 static boolean
247 elf_i386_check_relocs (abfd, info, sec, relocs)
248 bfd *abfd;
249 struct bfd_link_info *info;
250 asection *sec;
251 const Elf_Internal_Rela *relocs;
252 {
253 bfd *dynobj;
254 Elf_Internal_Shdr *symtab_hdr;
255 struct elf_link_hash_entry **sym_hashes;
256 bfd_vma *local_got_offsets;
257 const Elf_Internal_Rela *rel;
258 const Elf_Internal_Rela *rel_end;
259 asection *sgot;
260 asection *srelgot;
261 asection *sreloc;
262
263 if (info->relocateable)
264 return true;
265
266 dynobj = elf_hash_table (info)->dynobj;
267 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
268 sym_hashes = elf_sym_hashes (abfd);
269 local_got_offsets = elf_local_got_offsets (abfd);
270
271 sgot = NULL;
272 srelgot = NULL;
273 sreloc = NULL;
274
275 rel_end = relocs + sec->reloc_count;
276 for (rel = relocs; rel < rel_end; rel++)
277 {
278 unsigned long r_symndx;
279 struct elf_link_hash_entry *h;
280
281 r_symndx = ELF32_R_SYM (rel->r_info);
282
283 if (r_symndx < symtab_hdr->sh_info)
284 h = NULL;
285 else
286 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
287
288 /* Some relocs require a global offset table. */
289 if (dynobj == NULL)
290 {
291 switch (ELF32_R_TYPE (rel->r_info))
292 {
293 case R_386_GOT32:
294 case R_386_GOTOFF:
295 case R_386_GOTPC:
296 elf_hash_table (info)->dynobj = dynobj = abfd;
297 if (! _bfd_elf_create_got_section (dynobj, info))
298 return false;
299 break;
300
301 default:
302 break;
303 }
304 }
305
306 switch (ELF32_R_TYPE (rel->r_info))
307 {
308 case R_386_GOT32:
309 /* This symbol requires a global offset table entry. */
310
311 if (sgot == NULL)
312 {
313 sgot = bfd_get_section_by_name (dynobj, ".got");
314 BFD_ASSERT (sgot != NULL);
315 }
316
317 if (srelgot == NULL
318 && (h != NULL || info->shared))
319 {
320 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
321 if (srelgot == NULL)
322 {
323 srelgot = bfd_make_section (dynobj, ".rel.got");
324 if (srelgot == NULL
325 || ! bfd_set_section_flags (dynobj, srelgot,
326 (SEC_ALLOC
327 | SEC_LOAD
328 | SEC_HAS_CONTENTS
329 | SEC_IN_MEMORY
330 | SEC_READONLY))
331 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
332 return false;
333 }
334 }
335
336 if (h != NULL)
337 {
338 if (h->got_offset != (bfd_vma) -1)
339 {
340 /* We have already allocated space in the .got. */
341 break;
342 }
343 h->got_offset = sgot->_raw_size;
344
345 /* Make sure this symbol is output as a dynamic symbol. */
346 if (h->dynindx == -1)
347 {
348 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
349 return false;
350 }
351
352 srelgot->_raw_size += sizeof (Elf32_External_Rel);
353 }
354 else
355 {
356 /* This is a global offset table entry for a local
357 symbol. */
358 if (local_got_offsets == NULL)
359 {
360 size_t size;
361 register unsigned int i;
362
363 size = symtab_hdr->sh_info * sizeof (bfd_vma);
364 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
365 if (local_got_offsets == NULL)
366 return false;
367 elf_local_got_offsets (abfd) = local_got_offsets;
368 for (i = 0; i < symtab_hdr->sh_info; i++)
369 local_got_offsets[i] = (bfd_vma) -1;
370 }
371 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
372 {
373 /* We have already allocated space in the .got. */
374 break;
375 }
376 local_got_offsets[r_symndx] = sgot->_raw_size;
377
378 if (info->shared)
379 {
380 /* If we are generating a shared object, we need to
381 output a R_386_RELATIVE reloc so that the dynamic
382 linker can adjust this GOT entry. */
383 srelgot->_raw_size += sizeof (Elf32_External_Rel);
384 }
385 }
386
387 sgot->_raw_size += 4;
388
389 break;
390
391 case R_386_PLT32:
392 /* This symbol requires a procedure linkage table entry. We
393 actually build the entry in adjust_dynamic_symbol,
394 because this might be a case of linking PIC code without
395 linking in any dynamic objects, in which case we don't
396 need to generate a procedure linkage table after all. */
397
398 /* If this is a local symbol, we resolve it directly without
399 creating a procedure linkage table entry. */
400 if (h == NULL)
401 continue;
402
403 /* Make sure this symbol is output as a dynamic symbol. */
404 if (h->dynindx == -1)
405 {
406 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
407 return false;
408 }
409
410 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
411
412 break;
413
414 case R_386_32:
415 case R_386_PC32:
416 if (info->shared
417 && (sec->flags & SEC_ALLOC) != 0
418 && (ELF32_R_TYPE (rel->r_info) != R_386_PC32 || h != NULL))
419 {
420 /* When creating a shared object, we must copy these
421 reloc types into the output file. We create a reloc
422 section in dynobj and make room for this reloc. */
423 if (sreloc == NULL)
424 {
425 const char *name;
426
427 name = (bfd_elf_string_from_elf_section
428 (abfd,
429 elf_elfheader (abfd)->e_shstrndx,
430 elf_section_data (sec)->rel_hdr.sh_name));
431 if (name == NULL)
432 return false;
433
434 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
435 && strcmp (bfd_get_section_name (abfd, sec),
436 name + 4) == 0);
437
438 sreloc = bfd_get_section_by_name (dynobj, name);
439 if (sreloc == NULL)
440 {
441 sreloc = bfd_make_section (dynobj, name);
442 if (sreloc == NULL
443 || ! bfd_set_section_flags (dynobj, sreloc,
444 (SEC_ALLOC
445 | SEC_LOAD
446 | SEC_HAS_CONTENTS
447 | SEC_IN_MEMORY
448 | SEC_READONLY))
449 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
450 return false;
451 }
452 }
453
454 sreloc->_raw_size += sizeof (Elf32_External_Rel);
455 }
456
457 break;
458
459 default:
460 break;
461 }
462 }
463
464 return true;
465 }
466
467 /* Adjust a symbol defined by a dynamic object and referenced by a
468 regular object. The current definition is in some section of the
469 dynamic object, but we're not including those sections. We have to
470 change the definition to something the rest of the link can
471 understand. */
472
473 static boolean
474 elf_i386_adjust_dynamic_symbol (info, h)
475 struct bfd_link_info *info;
476 struct elf_link_hash_entry *h;
477 {
478 bfd *dynobj;
479 asection *s;
480 unsigned int power_of_two;
481
482 dynobj = elf_hash_table (info)->dynobj;
483
484 /* Make sure we know what is going on here. */
485 BFD_ASSERT (dynobj != NULL
486 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
487 || h->weakdef != NULL
488 || ((h->elf_link_hash_flags
489 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
490 && (h->elf_link_hash_flags
491 & ELF_LINK_HASH_REF_REGULAR) != 0
492 && (h->elf_link_hash_flags
493 & ELF_LINK_HASH_DEF_REGULAR) == 0)));
494
495 /* If this is a function, put it in the procedure linkage table. We
496 will fill in the contents of the procedure linkage table later,
497 when we know the address of the .got section. */
498 if (h->type == STT_FUNC
499 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
500 {
501 if (! elf_hash_table (info)->dynamic_sections_created)
502 {
503 /* This case can occur if we saw a PLT32 reloc in an input
504 file, but none of the input files were dynamic objects.
505 In such a case, we don't actually need to build a
506 procedure linkage table, and we can just do a PC32 reloc
507 instead. */
508 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
509 return true;
510 }
511
512 s = bfd_get_section_by_name (dynobj, ".plt");
513 BFD_ASSERT (s != NULL);
514
515 /* If this is the first .plt entry, make room for the special
516 first entry. */
517 if (s->_raw_size == 0)
518 s->_raw_size += PLT_ENTRY_SIZE;
519
520 /* If this symbol is not defined in a regular file, and we are
521 not generating a shared library, then set the symbol to this
522 location in the .plt. This is required to make function
523 pointers compare as equal between the normal executable and
524 the shared library. */
525 if (! info->shared
526 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
527 {
528 h->root.u.def.section = s;
529 h->root.u.def.value = s->_raw_size;
530 }
531
532 h->plt_offset = s->_raw_size;
533
534 /* Make room for this entry. */
535 s->_raw_size += PLT_ENTRY_SIZE;
536
537 /* We also need to make an entry in the .got.plt section, which
538 will be placed in the .got section by the linker script. */
539
540 s = bfd_get_section_by_name (dynobj, ".got.plt");
541 BFD_ASSERT (s != NULL);
542 s->_raw_size += 4;
543
544 /* We also need to make an entry in the .rel.plt section. */
545
546 s = bfd_get_section_by_name (dynobj, ".rel.plt");
547 BFD_ASSERT (s != NULL);
548 s->_raw_size += sizeof (Elf32_External_Rel);
549
550 return true;
551 }
552
553 /* If this is a weak symbol, and there is a real definition, the
554 processor independent code will have arranged for us to see the
555 real definition first, and we can just use the same value. */
556 if (h->weakdef != NULL)
557 {
558 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
559 || h->weakdef->root.type == bfd_link_hash_defweak);
560 h->root.u.def.section = h->weakdef->root.u.def.section;
561 h->root.u.def.value = h->weakdef->root.u.def.value;
562 return true;
563 }
564
565 /* This is a reference to a symbol defined by a dynamic object which
566 is not a function. */
567
568 /* If we are creating a shared library, we must presume that the
569 only references to the symbol are via the global offset table.
570 For such cases we need not do anything here; the relocations will
571 be handled correctly by relocate_section. */
572 if (info->shared)
573 return true;
574
575 /* We must allocate the symbol in our .dynbss section, which will
576 become part of the .bss section of the executable. There will be
577 an entry for this symbol in the .dynsym section. The dynamic
578 object will contain position independent code, so all references
579 from the dynamic object to this symbol will go through the global
580 offset table. The dynamic linker will use the .dynsym entry to
581 determine the address it must put in the global offset table, so
582 both the dynamic object and the regular object will refer to the
583 same memory location for the variable. */
584
585 s = bfd_get_section_by_name (dynobj, ".dynbss");
586 BFD_ASSERT (s != NULL);
587
588 /* If the symbol is currently defined in the .bss section of the
589 dynamic object, then it is OK to simply initialize it to zero.
590 If the symbol is in some other section, we must generate a
591 R_386_COPY reloc to tell the dynamic linker to copy the initial
592 value out of the dynamic object and into the runtime process
593 image. We need to remember the offset into the .rel.bss section
594 we are going to use. */
595 if ((h->root.u.def.section->flags & SEC_LOAD) != 0)
596 {
597 asection *srel;
598
599 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
600 BFD_ASSERT (srel != NULL);
601 srel->_raw_size += sizeof (Elf32_External_Rel);
602 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
603 }
604
605 /* We need to figure out the alignment required for this symbol. I
606 have no idea how ELF linkers handle this. */
607 power_of_two = bfd_log2 (h->size);
608 if (power_of_two > 3)
609 power_of_two = 3;
610
611 /* Apply the required alignment. */
612 s->_raw_size = BFD_ALIGN (s->_raw_size,
613 (bfd_size_type) (1 << power_of_two));
614 if (power_of_two > bfd_get_section_alignment (dynobj, s))
615 {
616 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
617 return false;
618 }
619
620 /* Define the symbol as being at this point in the section. */
621 h->root.u.def.section = s;
622 h->root.u.def.value = s->_raw_size;
623
624 /* Increment the section size to make room for the symbol. */
625 s->_raw_size += h->size;
626
627 return true;
628 }
629
630 /* Set the sizes of the dynamic sections. */
631
632 static boolean
633 elf_i386_size_dynamic_sections (output_bfd, info)
634 bfd *output_bfd;
635 struct bfd_link_info *info;
636 {
637 bfd *dynobj;
638 asection *s;
639 boolean plt;
640 boolean relocs;
641 boolean reltext;
642
643 dynobj = elf_hash_table (info)->dynobj;
644 BFD_ASSERT (dynobj != NULL);
645
646 if (elf_hash_table (info)->dynamic_sections_created)
647 {
648 /* Set the contents of the .interp section to the interpreter. */
649 if (! info->shared)
650 {
651 s = bfd_get_section_by_name (dynobj, ".interp");
652 BFD_ASSERT (s != NULL);
653 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
654 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
655 }
656 }
657 else
658 {
659 /* We may have created entries in the .rel.got section.
660 However, if we are not creating the dynamic sections, we will
661 not actually use these entries. Reset the size of .rel.got,
662 which will cause it to get stripped from the output file
663 below. */
664 s = bfd_get_section_by_name (dynobj, ".rel.got");
665 if (s != NULL)
666 s->_raw_size = 0;
667 }
668
669 /* The check_relocs and adjust_dynamic_symbol entry points have
670 determined the sizes of the various dynamic sections. Allocate
671 memory for them. */
672 plt = false;
673 relocs = false;
674 reltext = false;
675 for (s = dynobj->sections; s != NULL; s = s->next)
676 {
677 const char *name;
678 boolean strip;
679
680 if ((s->flags & SEC_IN_MEMORY) == 0)
681 continue;
682
683 /* It's OK to base decisions on the section name, because none
684 of the dynobj section names depend upon the input files. */
685 name = bfd_get_section_name (dynobj, s);
686
687 strip = false;
688
689 if (strcmp (name, ".plt") == 0)
690 {
691 if (s->_raw_size == 0)
692 {
693 /* Strip this section if we don't need it; see the
694 comment below. */
695 strip = true;
696 }
697 else
698 {
699 /* Remember whether there is a PLT. */
700 plt = true;
701 }
702 }
703 else if (strncmp (name, ".rel", 4) == 0)
704 {
705 if (s->_raw_size == 0)
706 {
707 /* If we don't need this section, strip it from the
708 output file. This is mostly to handle .rel.bss and
709 .rel.plt. We must create both sections in
710 create_dynamic_sections, because they must be created
711 before the linker maps input sections to output
712 sections. The linker does that before
713 adjust_dynamic_symbol is called, and it is that
714 function which decides whether anything needs to go
715 into these sections. */
716 strip = true;
717 }
718 else
719 {
720 asection *target;
721
722 /* Remember whether there are any reloc sections other
723 than .rel.plt. */
724 if (strcmp (name, ".rel.plt") != 0)
725 {
726 relocs = true;
727
728 /* If this relocation section applies to a read only
729 section, then we probably need a DT_TEXTREL
730 entry. The entries in the .rel.plt section
731 really apply to the .got section, which we
732 created ourselves and so know is not readonly. */
733 target = bfd_get_section_by_name (output_bfd, name + 4);
734 if (target != NULL
735 && (target->flags & SEC_READONLY) != 0)
736 reltext = true;
737 }
738
739 /* We use the reloc_count field as a counter if we need
740 to copy relocs into the output file. */
741 s->reloc_count = 0;
742 }
743 }
744 else if (strncmp (name, ".got", 4) != 0)
745 {
746 /* It's not one of our sections, so don't allocate space. */
747 continue;
748 }
749
750 if (strip)
751 {
752 asection **spp;
753
754 for (spp = &s->output_section->owner->sections;
755 *spp != s->output_section;
756 spp = &(*spp)->next)
757 ;
758 *spp = s->output_section->next;
759 --s->output_section->owner->section_count;
760
761 continue;
762 }
763
764 /* Allocate memory for the section contents. */
765 s->contents = (bfd_byte *) bfd_alloc (dynobj, s->_raw_size);
766 if (s->contents == NULL && s->_raw_size != 0)
767 return false;
768 }
769
770 if (elf_hash_table (info)->dynamic_sections_created)
771 {
772 /* Add some entries to the .dynamic section. We fill in the
773 values later, in elf_i386_finish_dynamic_sections, but we
774 must add the entries now so that we get the correct size for
775 the .dynamic section. The DT_DEBUG entry is filled in by the
776 dynamic linker and used by the debugger. */
777 if (! info->shared)
778 {
779 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
780 return false;
781 }
782
783 if (plt)
784 {
785 if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
786 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
787 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
788 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
789 return false;
790 }
791
792 if (relocs)
793 {
794 if (! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
795 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
796 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
797 sizeof (Elf32_External_Rel)))
798 return false;
799 }
800
801 if (reltext)
802 {
803 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
804 return false;
805 }
806 }
807
808 return true;
809 }
810
811 /* Relocate an i386 ELF section. */
812
813 static boolean
814 elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
815 contents, relocs, local_syms, local_sections)
816 bfd *output_bfd;
817 struct bfd_link_info *info;
818 bfd *input_bfd;
819 asection *input_section;
820 bfd_byte *contents;
821 Elf_Internal_Rela *relocs;
822 Elf_Internal_Sym *local_syms;
823 asection **local_sections;
824 {
825 bfd *dynobj;
826 Elf_Internal_Shdr *symtab_hdr;
827 struct elf_link_hash_entry **sym_hashes;
828 bfd_vma *local_got_offsets;
829 asection *sgot;
830 asection *splt;
831 asection *sreloc;
832 Elf_Internal_Rela *rel;
833 Elf_Internal_Rela *relend;
834
835 dynobj = elf_hash_table (info)->dynobj;
836 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
837 sym_hashes = elf_sym_hashes (input_bfd);
838 local_got_offsets = elf_local_got_offsets (input_bfd);
839
840 sgot = NULL;
841 splt = NULL;
842 sreloc = NULL;
843
844 rel = relocs;
845 relend = relocs + input_section->reloc_count;
846 for (; rel < relend; rel++)
847 {
848 int r_type;
849 reloc_howto_type *howto;
850 unsigned long r_symndx;
851 struct elf_link_hash_entry *h;
852 Elf_Internal_Sym *sym;
853 asection *sec;
854 bfd_vma relocation;
855 bfd_reloc_status_type r;
856
857 r_type = ELF32_R_TYPE (rel->r_info);
858 if (r_type < 0 || r_type >= (int) R_386_max)
859 {
860 bfd_set_error (bfd_error_bad_value);
861 return false;
862 }
863 howto = elf_howto_table + r_type;
864
865 r_symndx = ELF32_R_SYM (rel->r_info);
866
867 if (info->relocateable)
868 {
869 /* This is a relocateable link. We don't have to change
870 anything, unless the reloc is against a section symbol,
871 in which case we have to adjust according to where the
872 section symbol winds up in the output section. */
873 if (r_symndx < symtab_hdr->sh_info)
874 {
875 sym = local_syms + r_symndx;
876 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
877 {
878 bfd_vma val;
879
880 sec = local_sections[r_symndx];
881 val = bfd_get_32 (input_bfd, contents + rel->r_offset);
882 val += sec->output_offset + sym->st_value;
883 bfd_put_32 (input_bfd, val, contents + rel->r_offset);
884 }
885 }
886
887 continue;
888 }
889
890 /* This is a final link. */
891 h = NULL;
892 sym = NULL;
893 sec = NULL;
894 if (r_symndx < symtab_hdr->sh_info)
895 {
896 sym = local_syms + r_symndx;
897 sec = local_sections[r_symndx];
898 relocation = (sec->output_section->vma
899 + sec->output_offset
900 + sym->st_value);
901 }
902 else
903 {
904 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
905 while (h->root.type == bfd_link_hash_indirect
906 || h->root.type == bfd_link_hash_warning)
907 h = (struct elf_link_hash_entry *) h->root.u.i.link;
908 if (h->root.type == bfd_link_hash_defined
909 || h->root.type == bfd_link_hash_defweak)
910 {
911 sec = h->root.u.def.section;
912 if (r_type == R_386_GOTPC
913 || (r_type == R_386_PLT32
914 && h->plt_offset != (bfd_vma) -1)
915 || (r_type == R_386_GOT32
916 && elf_hash_table (info)->dynamic_sections_created
917 && (! info->shared
918 || ! info->symbolic
919 || (h->elf_link_hash_flags
920 & ELF_LINK_HASH_DEF_REGULAR) == 0))
921 || (info->shared
922 && (! info->symbolic
923 || (h->elf_link_hash_flags
924 & ELF_LINK_HASH_DEF_REGULAR) == 0)
925 && (r_type == R_386_32
926 || r_type == R_386_PC32)
927 && (input_section->flags & SEC_ALLOC) != 0))
928 {
929 /* In these cases, we don't need the relocation
930 value. We check specially because in some
931 obscure cases sec->output_section will be NULL. */
932 relocation = 0;
933 }
934 else
935 relocation = (h->root.u.def.value
936 + sec->output_section->vma
937 + sec->output_offset);
938 }
939 else if (h->root.type == bfd_link_hash_undefweak)
940 relocation = 0;
941 else if (info->shared && !info->symbolic)
942 relocation = 0;
943 else
944 {
945 if (! ((*info->callbacks->undefined_symbol)
946 (info, h->root.root.string, input_bfd,
947 input_section, rel->r_offset)))
948 return false;
949 relocation = 0;
950 }
951 }
952
953 switch (r_type)
954 {
955 case R_386_GOT32:
956 /* Relocation is to the entry for this symbol in the global
957 offset table. */
958 if (sgot == NULL)
959 {
960 sgot = bfd_get_section_by_name (dynobj, ".got");
961 BFD_ASSERT (sgot != NULL);
962 }
963
964 if (h != NULL)
965 {
966 bfd_vma off;
967
968 off = h->got_offset;
969 BFD_ASSERT (off != (bfd_vma) -1);
970
971 if (! elf_hash_table (info)->dynamic_sections_created
972 || (info->shared
973 && info->symbolic
974 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
975 {
976 /* This is actually a static link, or it is a
977 -Bsymbolic link and the symbol is defined
978 locally. We must initialize this entry in the
979 global offset table. Since the offset must
980 always be a multiple of 4, we use the least
981 significant bit to record whether we have
982 initialized it already.
983
984 When doing a dynamic link, we create a .rel.got
985 relocation entry to initialize the value. This
986 is done in the finish_dynamic_symbol routine. */
987 if ((off & 1) != 0)
988 off &= ~1;
989 else
990 {
991 bfd_put_32 (output_bfd, relocation,
992 sgot->contents + off);
993 h->got_offset |= 1;
994 }
995 }
996
997 relocation = sgot->output_offset + off;
998 }
999 else
1000 {
1001 bfd_vma off;
1002
1003 BFD_ASSERT (local_got_offsets != NULL
1004 && local_got_offsets[r_symndx] != (bfd_vma) -1);
1005
1006 off = local_got_offsets[r_symndx];
1007
1008 /* The offset must always be a multiple of 4. We use
1009 the least significant bit to record whether we have
1010 already generated the necessary reloc. */
1011 if ((off & 1) != 0)
1012 off &= ~1;
1013 else
1014 {
1015 bfd_put_32 (output_bfd, relocation, sgot->contents + off);
1016
1017 if (info->shared)
1018 {
1019 asection *srelgot;
1020 Elf_Internal_Rel outrel;
1021
1022 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1023 BFD_ASSERT (srelgot != NULL);
1024
1025 outrel.r_offset = (sgot->output_section->vma
1026 + sgot->output_offset
1027 + off);
1028 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1029 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1030 (((Elf32_External_Rel *)
1031 srelgot->contents)
1032 + srelgot->reloc_count));
1033 ++srelgot->reloc_count;
1034 }
1035
1036 local_got_offsets[r_symndx] |= 1;
1037 }
1038
1039 relocation = sgot->output_offset + off;
1040 }
1041
1042 break;
1043
1044 case R_386_GOTOFF:
1045 /* Relocation is relative to the start of the global offset
1046 table. */
1047
1048 if (sgot == NULL)
1049 {
1050 sgot = bfd_get_section_by_name (dynobj, ".got");
1051 BFD_ASSERT (sgot != NULL);
1052 }
1053
1054 /* Note that sgot->output_offset is not involved in this
1055 calculation. We always want the start of .got. If we
1056 defined _GLOBAL_OFFSET_TABLE in a different way, as is
1057 permitted by the ABI, we might have to change this
1058 calculation. */
1059 relocation -= sgot->output_section->vma;
1060
1061 break;
1062
1063 case R_386_GOTPC:
1064 /* Use global offset table as symbol value. */
1065
1066 if (sgot == NULL)
1067 {
1068 sgot = bfd_get_section_by_name (dynobj, ".got");
1069 BFD_ASSERT (sgot != NULL);
1070 }
1071
1072 relocation = sgot->output_section->vma;
1073
1074 break;
1075
1076 case R_386_PLT32:
1077 /* Relocation is to the entry for this symbol in the
1078 procedure linkage table. */
1079
1080 /* Resolve a PLT32 reloc again a local symbol directly,
1081 without using the procedure linkage table. */
1082 if (h == NULL)
1083 break;
1084
1085 if (h->plt_offset == (bfd_vma) -1)
1086 {
1087 /* We didn't make a PLT entry for this symbol. This
1088 happens when statically linking PIC code, or when
1089 using -Bsymbolic. */
1090 break;
1091 }
1092
1093 if (splt == NULL)
1094 {
1095 splt = bfd_get_section_by_name (dynobj, ".plt");
1096 BFD_ASSERT (splt != NULL);
1097 }
1098
1099 relocation = (splt->output_section->vma
1100 + splt->output_offset
1101 + h->plt_offset);
1102
1103 break;
1104
1105 case R_386_32:
1106 case R_386_PC32:
1107 if (info->shared
1108 && (input_section->flags & SEC_ALLOC) != 0
1109 && (r_type != R_386_PC32
1110 || (h != NULL
1111 && (! info->symbolic
1112 || (h->elf_link_hash_flags
1113 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1114 {
1115 Elf_Internal_Rel outrel;
1116 boolean relocate;
1117
1118 /* When generating a shared object, these relocations
1119 are copied into the output file to be resolved at run
1120 time. */
1121
1122 if (sreloc == NULL)
1123 {
1124 const char *name;
1125
1126 name = (bfd_elf_string_from_elf_section
1127 (input_bfd,
1128 elf_elfheader (input_bfd)->e_shstrndx,
1129 elf_section_data (input_section)->rel_hdr.sh_name));
1130 if (name == NULL)
1131 return false;
1132
1133 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1134 && strcmp (bfd_get_section_name (input_bfd,
1135 input_section),
1136 name + 4) == 0);
1137
1138 sreloc = bfd_get_section_by_name (dynobj, name);
1139 BFD_ASSERT (sreloc != NULL);
1140 }
1141
1142 outrel.r_offset = (rel->r_offset
1143 + input_section->output_section->vma
1144 + input_section->output_offset);
1145 if (r_type == R_386_PC32)
1146 {
1147 BFD_ASSERT (h != NULL && h->dynindx != -1);
1148 relocate = false;
1149 outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_PC32);
1150 }
1151 else
1152 {
1153 if (h == NULL
1154 || (info->symbolic
1155 && (h->elf_link_hash_flags
1156 & ELF_LINK_HASH_DEF_REGULAR) != 0))
1157 {
1158 relocate = true;
1159 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1160 }
1161 else
1162 {
1163 BFD_ASSERT (h->dynindx != -1);
1164 relocate = false;
1165 outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_32);
1166 }
1167 }
1168
1169 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1170 (((Elf32_External_Rel *)
1171 sreloc->contents)
1172 + sreloc->reloc_count));
1173 ++sreloc->reloc_count;
1174
1175 /* If this reloc is against an external symbol, we do
1176 not want to fiddle with the addend. Otherwise, we
1177 need to include the symbol value so that it becomes
1178 an addend for the dynamic reloc. */
1179 if (! relocate)
1180 continue;
1181 }
1182
1183 break;
1184
1185 default:
1186 break;
1187 }
1188
1189 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1190 contents, rel->r_offset,
1191 relocation, (bfd_vma) 0);
1192
1193 if (r != bfd_reloc_ok)
1194 {
1195 switch (r)
1196 {
1197 default:
1198 case bfd_reloc_outofrange:
1199 abort ();
1200 case bfd_reloc_overflow:
1201 {
1202 const char *name;
1203
1204 if (h != NULL)
1205 name = h->root.root.string;
1206 else
1207 {
1208 name = bfd_elf_string_from_elf_section (input_bfd,
1209 symtab_hdr->sh_link,
1210 sym->st_name);
1211 if (name == NULL)
1212 return false;
1213 if (*name == '\0')
1214 name = bfd_section_name (input_bfd, sec);
1215 }
1216 if (! ((*info->callbacks->reloc_overflow)
1217 (info, name, howto->name, (bfd_vma) 0,
1218 input_bfd, input_section, rel->r_offset)))
1219 return false;
1220 }
1221 break;
1222 }
1223 }
1224 }
1225
1226 return true;
1227 }
1228
1229 /* Finish up dynamic symbol handling. We set the contents of various
1230 dynamic sections here. */
1231
1232 static boolean
1233 elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
1234 bfd *output_bfd;
1235 struct bfd_link_info *info;
1236 struct elf_link_hash_entry *h;
1237 Elf_Internal_Sym *sym;
1238 {
1239 bfd *dynobj;
1240
1241 dynobj = elf_hash_table (info)->dynobj;
1242
1243 if (h->plt_offset != (bfd_vma) -1)
1244 {
1245 asection *splt;
1246 asection *sgot;
1247 asection *srel;
1248 bfd_vma plt_index;
1249 bfd_vma got_offset;
1250 Elf_Internal_Rel rel;
1251
1252 /* This symbol has an entry in the procedure linkage table. Set
1253 it up. */
1254
1255 BFD_ASSERT (h->dynindx != -1);
1256
1257 splt = bfd_get_section_by_name (dynobj, ".plt");
1258 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1259 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
1260 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
1261
1262 /* Get the index in the procedure linkage table which
1263 corresponds to this symbol. This is the index of this symbol
1264 in all the symbols for which we are making plt entries. The
1265 first entry in the procedure linkage table is reserved. */
1266 plt_index = h->plt_offset / PLT_ENTRY_SIZE - 1;
1267
1268 /* Get the offset into the .got table of the entry that
1269 corresponds to this function. Each .got entry is 4 bytes.
1270 The first three are reserved. */
1271 got_offset = (plt_index + 3) * 4;
1272
1273 /* Fill in the entry in the procedure linkage table. */
1274 if (! info->shared)
1275 {
1276 memcpy (splt->contents + h->plt_offset, elf_i386_plt_entry,
1277 PLT_ENTRY_SIZE);
1278 bfd_put_32 (output_bfd,
1279 (sgot->output_section->vma
1280 + sgot->output_offset
1281 + got_offset),
1282 splt->contents + h->plt_offset + 2);
1283 }
1284 else
1285 {
1286 memcpy (splt->contents + h->plt_offset, elf_i386_pic_plt_entry,
1287 PLT_ENTRY_SIZE);
1288 bfd_put_32 (output_bfd, got_offset,
1289 splt->contents + h->plt_offset + 2);
1290 }
1291
1292 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
1293 splt->contents + h->plt_offset + 7);
1294 bfd_put_32 (output_bfd, - (h->plt_offset + PLT_ENTRY_SIZE),
1295 splt->contents + h->plt_offset + 12);
1296
1297 /* Fill in the entry in the global offset table. */
1298 bfd_put_32 (output_bfd,
1299 (splt->output_section->vma
1300 + splt->output_offset
1301 + h->plt_offset
1302 + 6),
1303 sgot->contents + got_offset);
1304
1305 /* Fill in the entry in the .rel.plt section. */
1306 rel.r_offset = (sgot->output_section->vma
1307 + sgot->output_offset
1308 + got_offset);
1309 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
1310 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1311 ((Elf32_External_Rel *) srel->contents
1312 + plt_index));
1313
1314 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1315 {
1316 /* Mark the symbol as undefined, rather than as defined in
1317 the .plt section. Leave the value alone. */
1318 sym->st_shndx = SHN_UNDEF;
1319 }
1320 }
1321
1322 if (h->got_offset != (bfd_vma) -1)
1323 {
1324 asection *sgot;
1325 asection *srel;
1326 Elf_Internal_Rel rel;
1327
1328 /* This symbol has an entry in the global offset table. Set it
1329 up. */
1330
1331 BFD_ASSERT (h->dynindx != -1);
1332
1333 sgot = bfd_get_section_by_name (dynobj, ".got");
1334 srel = bfd_get_section_by_name (dynobj, ".rel.got");
1335 BFD_ASSERT (sgot != NULL && srel != NULL);
1336
1337 rel.r_offset = (sgot->output_section->vma
1338 + sgot->output_offset
1339 + (h->got_offset &~ 1));
1340
1341 /* If this is a -Bsymbolic link, and the symbol is defined
1342 locally, we just want to emit a RELATIVE reloc. The entry in
1343 the global offset table will already have been initialized in
1344 the relocate_section function. */
1345 if (info->shared
1346 && info->symbolic
1347 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
1348 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1349 else
1350 {
1351 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got_offset);
1352 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
1353 }
1354
1355 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1356 ((Elf32_External_Rel *) srel->contents
1357 + srel->reloc_count));
1358 ++srel->reloc_count;
1359 }
1360
1361 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
1362 {
1363 asection *s;
1364 Elf_Internal_Rel rel;
1365
1366 /* This symbol needs a copy reloc. Set it up. */
1367
1368 BFD_ASSERT (h->dynindx != -1
1369 && (h->root.type == bfd_link_hash_defined
1370 || h->root.type == bfd_link_hash_defweak));
1371
1372 s = bfd_get_section_by_name (h->root.u.def.section->owner,
1373 ".rel.bss");
1374 BFD_ASSERT (s != NULL);
1375
1376 rel.r_offset = (h->root.u.def.value
1377 + h->root.u.def.section->output_section->vma
1378 + h->root.u.def.section->output_offset);
1379 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
1380 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1381 ((Elf32_External_Rel *) s->contents
1382 + s->reloc_count));
1383 ++s->reloc_count;
1384 }
1385
1386 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
1387 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
1388 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
1389 sym->st_shndx = SHN_ABS;
1390
1391 return true;
1392 }
1393
1394 /* Finish up the dynamic sections. */
1395
1396 static boolean
1397 elf_i386_finish_dynamic_sections (output_bfd, info)
1398 bfd *output_bfd;
1399 struct bfd_link_info *info;
1400 {
1401 bfd *dynobj;
1402 asection *sgot;
1403 asection *sdyn;
1404
1405 dynobj = elf_hash_table (info)->dynobj;
1406
1407 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1408 BFD_ASSERT (sgot != NULL);
1409 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
1410
1411 if (elf_hash_table (info)->dynamic_sections_created)
1412 {
1413 asection *splt;
1414 Elf32_External_Dyn *dyncon, *dynconend;
1415
1416 splt = bfd_get_section_by_name (dynobj, ".plt");
1417 BFD_ASSERT (splt != NULL && sdyn != NULL);
1418
1419 dyncon = (Elf32_External_Dyn *) sdyn->contents;
1420 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
1421 for (; dyncon < dynconend; dyncon++)
1422 {
1423 Elf_Internal_Dyn dyn;
1424 const char *name;
1425 asection *s;
1426
1427 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
1428
1429 switch (dyn.d_tag)
1430 {
1431 default:
1432 break;
1433
1434 case DT_PLTGOT:
1435 name = ".got";
1436 goto get_vma;
1437 case DT_JMPREL:
1438 name = ".rel.plt";
1439 get_vma:
1440 s = bfd_get_section_by_name (output_bfd, name);
1441 BFD_ASSERT (s != NULL);
1442 dyn.d_un.d_ptr = s->vma;
1443 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1444 break;
1445
1446 case DT_PLTRELSZ:
1447 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
1448 BFD_ASSERT (s != NULL);
1449 if (s->_cooked_size != 0)
1450 dyn.d_un.d_val = s->_cooked_size;
1451 else
1452 dyn.d_un.d_val = s->_raw_size;
1453 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1454 break;
1455
1456 case DT_RELSZ:
1457 /* My reading of the SVR4 ABI indicates that the
1458 procedure linkage table relocs (DT_JMPREL) should be
1459 included in the overall relocs (DT_REL). This is
1460 what Solaris does. However, UnixWare can not handle
1461 that case. Therefore, we override the DT_RELSZ entry
1462 here to make it not include the JMPREL relocs. Since
1463 the linker script arranges for .rel.plt to follow all
1464 other relocation sections, we don't have to worry
1465 about changing the DT_REL entry. */
1466 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
1467 if (s != NULL)
1468 {
1469 if (s->_cooked_size != 0)
1470 dyn.d_un.d_val -= s->_cooked_size;
1471 else
1472 dyn.d_un.d_val -= s->_raw_size;
1473 }
1474 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1475 break;
1476 }
1477 }
1478
1479 /* Fill in the first entry in the procedure linkage table. */
1480 if (splt->_raw_size > 0)
1481 {
1482 if (info->shared)
1483 memcpy (splt->contents, elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
1484 else
1485 {
1486 memcpy (splt->contents, elf_i386_plt0_entry, PLT_ENTRY_SIZE);
1487 bfd_put_32 (output_bfd,
1488 sgot->output_section->vma + sgot->output_offset + 4,
1489 splt->contents + 2);
1490 bfd_put_32 (output_bfd,
1491 sgot->output_section->vma + sgot->output_offset + 8,
1492 splt->contents + 8);
1493 }
1494 }
1495
1496 /* UnixWare sets the entsize of .plt to 4, although that doesn't
1497 really seem like the right value. */
1498 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
1499 }
1500
1501 /* Fill in the first three entries in the global offset table. */
1502 if (sgot->_raw_size > 0)
1503 {
1504 if (sdyn == NULL)
1505 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
1506 else
1507 bfd_put_32 (output_bfd,
1508 sdyn->output_section->vma + sdyn->output_offset,
1509 sgot->contents);
1510 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
1511 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
1512 }
1513
1514 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
1515
1516 return true;
1517 }
1518
1519 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
1520 #define TARGET_LITTLE_NAME "elf32-i386"
1521 #define ELF_ARCH bfd_arch_i386
1522 #define ELF_MACHINE_CODE EM_386
1523 #define elf_info_to_howto elf_i386_info_to_howto
1524 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
1525 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
1526 #define ELF_MAXPAGESIZE 0x1000
1527 #define elf_backend_create_dynamic_sections \
1528 _bfd_elf_create_dynamic_sections
1529 #define elf_backend_check_relocs elf_i386_check_relocs
1530 #define elf_backend_adjust_dynamic_symbol \
1531 elf_i386_adjust_dynamic_symbol
1532 #define elf_backend_size_dynamic_sections \
1533 elf_i386_size_dynamic_sections
1534 #define elf_backend_relocate_section elf_i386_relocate_section
1535 #define elf_backend_finish_dynamic_symbol \
1536 elf_i386_finish_dynamic_symbol
1537 #define elf_backend_finish_dynamic_sections \
1538 elf_i386_finish_dynamic_sections
1539 #define elf_backend_want_got_plt 1
1540 #define elf_backend_plt_readonly 1
1541 #define elf_backend_want_plt_sym 0
1542
1543 #include "elf32-target.h"
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