remove unused variable
[deliverable/binutils-gdb.git] / bfd / elf32-i386.c
1 /* Intel 80386/80486-specific support for 32-bit ELF
2 Copyright 1993 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
19
20 #include "bfd.h"
21 #include "sysdep.h"
22 #include "bfdlink.h"
23 #include "libbfd.h"
24 #include "libelf.h"
25
26 static CONST struct reloc_howto_struct *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_create_dynamic_sections
33 PARAMS ((bfd *, struct bfd_link_info *));
34 static boolean elf_i386_create_got_section
35 PARAMS ((bfd *, struct bfd_link_info *));
36 static boolean elf_i386_check_relocs
37 PARAMS ((bfd *, struct bfd_link_info *, asection *,
38 const Elf_Internal_Rela *));
39 static boolean elf_i386_adjust_dynamic_symbol
40 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
41 static boolean elf_i386_size_dynamic_sections
42 PARAMS ((bfd *, struct bfd_link_info *));
43 static boolean elf_i386_relocate_section
44 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
45 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
46 static boolean elf_i386_finish_dynamic_symbol
47 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
48 Elf_Internal_Sym *));
49 static boolean elf_i386_finish_dynamic_sections
50 PARAMS ((bfd *, struct bfd_link_info *));
51
52 #define USE_REL 1 /* 386 uses REL relocations instead of RELA */
53
54 enum reloc_type
55 {
56 R_386_NONE = 0,
57 R_386_32,
58 R_386_PC32,
59 R_386_GOT32,
60 R_386_PLT32,
61 R_386_COPY,
62 R_386_GLOB_DAT,
63 R_386_JUMP_SLOT,
64 R_386_RELATIVE,
65 R_386_GOTOFF,
66 R_386_GOTPC,
67 R_386_max
68 };
69
70 #if 0
71 static CONST char *CONST reloc_type_names[] =
72 {
73 "R_386_NONE",
74 "R_386_32",
75 "R_386_PC32",
76 "R_386_GOT32",
77 "R_386_PLT32",
78 "R_386_COPY",
79 "R_386_GLOB_DAT",
80 "R_386_JUMP_SLOT",
81 "R_386_RELATIVE",
82 "R_386_GOTOFF",
83 "R_386_GOTPC",
84 };
85 #endif
86
87 static reloc_howto_type elf_howto_table[]=
88 {
89 HOWTO(R_386_NONE, 0,0, 0,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_NONE", true,0x00000000,0x00000000,false),
90 HOWTO(R_386_32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_32", true,0xffffffff,0xffffffff,false),
91 HOWTO(R_386_PC32, 0,2,32,true, 0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PC32", true,0xffffffff,0xffffffff,true),
92 HOWTO(R_386_GOT32, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOT32", true,0xffffffff,0xffffffff,false),
93 HOWTO(R_386_PLT32, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_PLT32", true,0xffffffff,0xffffffff,true),
94 HOWTO(R_386_COPY, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_COPY", true,0xffffffff,0xffffffff,false),
95 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),
96 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),
97 HOWTO(R_386_RELATIVE, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_RELATIVE", true,0xffffffff,0xffffffff,false),
98 HOWTO(R_386_GOTOFF, 0,2,32,false,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTOFF", true,0xffffffff,0xffffffff,false),
99 HOWTO(R_386_GOTPC, 0,2,32,true,0,complain_overflow_bitfield, bfd_elf_generic_reloc,"R_386_GOTPC", true,0xffffffff,0xffffffff,true),
100 };
101
102 #ifdef DEBUG_GEN_RELOC
103 #define TRACE(str) fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
104 #else
105 #define TRACE(str)
106 #endif
107
108 static CONST struct reloc_howto_struct *
109 elf_i386_reloc_type_lookup (abfd, code)
110 bfd *abfd;
111 bfd_reloc_code_real_type code;
112 {
113 switch (code)
114 {
115 case BFD_RELOC_NONE:
116 TRACE ("BFD_RELOC_NONE");
117 return &elf_howto_table[ (int)R_386_NONE ];
118
119 case BFD_RELOC_32:
120 TRACE ("BFD_RELOC_32");
121 return &elf_howto_table[ (int)R_386_32 ];
122
123 case BFD_RELOC_32_PCREL:
124 TRACE ("BFD_RELOC_PC32");
125 return &elf_howto_table[ (int)R_386_PC32 ];
126
127 case BFD_RELOC_386_GOT32:
128 TRACE ("BFD_RELOC_386_GOT32");
129 return &elf_howto_table[ (int)R_386_GOT32 ];
130
131 case BFD_RELOC_386_PLT32:
132 TRACE ("BFD_RELOC_386_PLT32");
133 return &elf_howto_table[ (int)R_386_PLT32 ];
134
135 case BFD_RELOC_386_COPY:
136 TRACE ("BFD_RELOC_386_COPY");
137 return &elf_howto_table[ (int)R_386_COPY ];
138
139 case BFD_RELOC_386_GLOB_DAT:
140 TRACE ("BFD_RELOC_386_GLOB_DAT");
141 return &elf_howto_table[ (int)R_386_GLOB_DAT ];
142
143 case BFD_RELOC_386_JUMP_SLOT:
144 TRACE ("BFD_RELOC_386_JUMP_SLOT");
145 return &elf_howto_table[ (int)R_386_JUMP_SLOT ];
146
147 case BFD_RELOC_386_RELATIVE:
148 TRACE ("BFD_RELOC_386_RELATIVE");
149 return &elf_howto_table[ (int)R_386_RELATIVE ];
150
151 case BFD_RELOC_386_GOTOFF:
152 TRACE ("BFD_RELOC_386_GOTOFF");
153 return &elf_howto_table[ (int)R_386_GOTOFF ];
154
155 case BFD_RELOC_386_GOTPC:
156 TRACE ("BFD_RELOC_386_GOTPC");
157 return &elf_howto_table[ (int)R_386_GOTPC ];
158
159 default:
160 break;
161 }
162
163 TRACE ("Unknown");
164 return 0;
165 }
166
167 static void
168 elf_i386_info_to_howto (abfd, cache_ptr, dst)
169 bfd *abfd;
170 arelent *cache_ptr;
171 Elf32_Internal_Rela *dst;
172 {
173 BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
174
175 cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
176 }
177
178 static void
179 elf_i386_info_to_howto_rel (abfd, cache_ptr, dst)
180 bfd *abfd;
181 arelent *cache_ptr;
182 Elf32_Internal_Rel *dst;
183 {
184 BFD_ASSERT (ELF32_R_TYPE(dst->r_info) < (unsigned int) R_386_max);
185
186 cache_ptr->howto = &elf_howto_table[ELF32_R_TYPE(dst->r_info)];
187 }
188 \f
189 /* Functions for the i386 ELF linker. */
190
191 /* The name of the dynamic interpreter. This is put in the .interp
192 section. */
193
194 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
195
196 /* The size in bytes of an entry in the procedure linkage table. */
197
198 #define PLT_ENTRY_SIZE 16
199
200 /* The first entry in an absolute procedure linkage table looks like
201 this. See the SVR4 ABI i386 supplement to see how this works. */
202
203 static bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
204 {
205 0xff, 0x35, /* pushl contents of address */
206 0, 0, 0, 0, /* replaced with address of .got + 4. */
207 0xff, 0x25, /* jmp indirect */
208 0, 0, 0, 0, /* replaced with address of .got + 8. */
209 0, 0, 0, 0 /* pad out to 16 bytes. */
210 };
211
212 /* Subsequent entries in an absolute procedure linkage table look like
213 this. */
214
215 static bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
216 {
217 0xff, 0x25, /* jmp indirect */
218 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
219 0x68, /* pushl immediate */
220 0, 0, 0, 0, /* replaced with offset into relocation table. */
221 0xe9, /* jmp relative */
222 0, 0, 0, 0 /* replaced with offset to start of .plt. */
223 };
224
225 /* The first entry in a PIC procedure linkage table look like this. */
226
227 static bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
228 {
229 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
230 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
231 0, 0, 0, 0 /* pad out to 16 bytes. */
232 };
233
234 /* Subsequent entries in a PIC procedure linkage table look like this. */
235
236 static bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
237 {
238 0xff, 0xa3, /* jmp *offset(%ebx) */
239 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
240 0x68, /* pushl immediate */
241 0, 0, 0, 0, /* replaced with offset into relocation table. */
242 0xe9, /* jmp relative */
243 0, 0, 0, 0 /* replaced with offset to start of .plt. */
244 };
245
246 /* Create dynamic sections when linking against a dynamic object. */
247
248 static boolean
249 elf_i386_create_dynamic_sections (abfd, info)
250 bfd *abfd;
251 struct bfd_link_info *info;
252 {
253 flagword flags;
254 register asection *s;
255
256 /* We need to create .plt, .rel.plt, .got, .got.plt, .dynbss, and
257 .rel.bss sections. */
258
259 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
260
261 s = bfd_make_section (abfd, ".plt");
262 if (s == NULL
263 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY | SEC_CODE)
264 || ! bfd_set_section_alignment (abfd, s, 2))
265 return false;
266
267 s = bfd_make_section (abfd, ".rel.plt");
268 if (s == NULL
269 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
270 || ! bfd_set_section_alignment (abfd, s, 2))
271 return false;
272
273 if (! elf_i386_create_got_section (abfd, info))
274 return false;
275
276 /* The .dynbss section is a place to put symbols which are defined
277 by dynamic objects, are referenced by regular objects, and are
278 not functions. We must allocate space for them in the process
279 image and use a R_386_COPY reloc to tell the dynamic linker to
280 initialize them at run time. The linker script puts the .dynbss
281 section into the .bss section of the final image. */
282 s = bfd_make_section (abfd, ".dynbss");
283 if (s == NULL
284 || ! bfd_set_section_flags (abfd, s, SEC_ALLOC))
285 return false;
286
287 /* The .rel.bss section holds copy relocs. This section is not
288 normally needed. We need to create it here, though, so that the
289 linker will map it to an output section. We can't just create it
290 only if we need it, because we will not know whether we need it
291 until we have seen all the input files, and the first time the
292 main linker code calls BFD after examining all the input files
293 (size_dynamic_sections) the input sections have already been
294 mapped to the output sections. If the section turns out not to
295 be needed, we can discard it later. We will never need this
296 section when generating a shared object, since they do not use
297 copy relocs. */
298 if (! info->shared)
299 {
300 s = bfd_make_section (abfd, ".rel.bss");
301 if (s == NULL
302 || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)
303 || ! bfd_set_section_alignment (abfd, s, 2))
304 return false;
305 }
306
307 return true;
308 }
309
310 /* Create the .got section to hold the global offset table, and the
311 .got.plt section to hold procedure linkage table GOT entries. The
312 linker script will put .got.plt into the output .got section. */
313
314 static boolean
315 elf_i386_create_got_section (abfd, info)
316 bfd *abfd;
317 struct bfd_link_info *info;
318 {
319 flagword flags;
320 register asection *s;
321 struct elf_link_hash_entry *h;
322
323 /* This function may be called more than once. */
324 if (bfd_get_section_by_name (abfd, ".got") != NULL)
325 return true;
326
327 flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY;
328
329 s = bfd_make_section (abfd, ".got");
330 if (s == NULL
331 || ! bfd_set_section_flags (abfd, s, flags)
332 || ! bfd_set_section_alignment (abfd, s, 2))
333 return false;
334
335 s = bfd_make_section (abfd, ".got.plt");
336 if (s == NULL
337 || ! bfd_set_section_flags (abfd, s, flags)
338 || ! bfd_set_section_alignment (abfd, s, 2))
339 return false;
340
341 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the
342 .got.plt section, which will be placed at the start of the output
343 .got section. We don't do this in the linker script because we
344 don't want to define the symbol if we are not creating a global
345 offset table. */
346 h = NULL;
347 if (! (_bfd_generic_link_add_one_symbol
348 (info, abfd, "_GLOBAL_OFFSET_TABLE_", BSF_GLOBAL, s, (bfd_vma) 0,
349 (const char *) NULL, false, get_elf_backend_data (abfd)->collect,
350 (struct bfd_link_hash_entry **) &h)))
351 return false;
352 h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR;
353 h->type = STT_OBJECT;
354
355 if (info->shared
356 && ! bfd_elf32_link_record_dynamic_symbol (info, h))
357 return false;
358
359 /* The first three global offset table entries are reserved. */
360 s->_raw_size += 3 * 4;
361
362 return true;
363 }
364
365 /* Look through the relocs for a section during the first phase, and
366 allocate space in the global offset table or procedure linkage
367 table. */
368
369 static boolean
370 elf_i386_check_relocs (abfd, info, sec, relocs)
371 bfd *abfd;
372 struct bfd_link_info *info;
373 asection *sec;
374 const Elf_Internal_Rela *relocs;
375 {
376 bfd *dynobj;
377 Elf_Internal_Shdr *symtab_hdr;
378 struct elf_link_hash_entry **sym_hashes;
379 bfd_vma *local_got_offsets;
380 const Elf_Internal_Rela *rel;
381 const Elf_Internal_Rela *rel_end;
382 asection *sgot;
383 asection *srelgot;
384 asection *sreloc;
385
386 if (info->relocateable)
387 return true;
388
389 dynobj = elf_hash_table (info)->dynobj;
390 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
391 sym_hashes = elf_sym_hashes (abfd);
392 local_got_offsets = elf_local_got_offsets (abfd);
393
394 sgot = NULL;
395 srelgot = NULL;
396 sreloc = NULL;
397
398 rel_end = relocs + sec->reloc_count;
399 for (rel = relocs; rel < rel_end; rel++)
400 {
401 long r_symndx;
402 struct elf_link_hash_entry *h;
403
404 r_symndx = ELF32_R_SYM (rel->r_info);
405
406 if (r_symndx < symtab_hdr->sh_info)
407 h = NULL;
408 else
409 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
410
411 /* Some relocs require a global offset table. */
412 if (dynobj == NULL)
413 {
414 switch (ELF32_R_TYPE (rel->r_info))
415 {
416 case R_386_GOT32:
417 case R_386_GOTOFF:
418 case R_386_GOTPC:
419 elf_hash_table (info)->dynobj = dynobj = abfd;
420 if (! elf_i386_create_got_section (dynobj, info))
421 return false;
422 break;
423
424 default:
425 break;
426 }
427 }
428
429 switch (ELF32_R_TYPE (rel->r_info))
430 {
431 case R_386_GOT32:
432 /* This symbol requires a global offset table entry. */
433
434 if (sgot == NULL)
435 {
436 sgot = bfd_get_section_by_name (dynobj, ".got");
437 BFD_ASSERT (sgot != NULL);
438 }
439
440 if (srelgot == NULL
441 && (h != NULL || info->shared))
442 {
443 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
444 if (srelgot == NULL)
445 {
446 srelgot = bfd_make_section (dynobj, ".rel.got");
447 if (srelgot == NULL
448 || ! bfd_set_section_flags (dynobj, srelgot,
449 (SEC_ALLOC
450 | SEC_LOAD
451 | SEC_HAS_CONTENTS
452 | SEC_IN_MEMORY
453 | SEC_READONLY))
454 || ! bfd_set_section_alignment (dynobj, srelgot, 2))
455 return false;
456 }
457 }
458
459 if (h != NULL)
460 {
461 if (h->got_offset != (bfd_vma) -1)
462 {
463 /* We have already allocated space in the .got. */
464 break;
465 }
466 h->got_offset = sgot->_raw_size;
467
468 /* Make sure this symbol is output as a dynamic symbol. */
469 if (h->dynindx == -1)
470 {
471 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
472 return false;
473 }
474
475 srelgot->_raw_size += sizeof (Elf32_External_Rel);
476 }
477 else
478 {
479 /* This is a global offset table entry for a local
480 symbol. */
481 if (local_got_offsets == NULL)
482 {
483 size_t size;
484 register int i;
485
486 size = symtab_hdr->sh_info * sizeof (bfd_vma);
487 local_got_offsets = (bfd_vma *) bfd_alloc (abfd, size);
488 if (local_got_offsets == NULL)
489 {
490 bfd_set_error (bfd_error_no_memory);
491 return false;
492 }
493 elf_local_got_offsets (abfd) = local_got_offsets;
494 for (i = 0; i < symtab_hdr->sh_info; i++)
495 local_got_offsets[i] = (bfd_vma) -1;
496 }
497 if (local_got_offsets[r_symndx] != (bfd_vma) -1)
498 {
499 /* We have already allocated space in the .got. */
500 break;
501 }
502 local_got_offsets[r_symndx] = sgot->_raw_size;
503
504 if (info->shared)
505 {
506 /* If we are generating a shared object, we need to
507 output a R_386_RELATIVE reloc so that the dynamic
508 linker can adjust this GOT entry. */
509 srelgot->_raw_size += sizeof (Elf32_External_Rel);
510 }
511 }
512
513 sgot->_raw_size += 4;
514
515 break;
516
517 case R_386_PLT32:
518 /* This symbol requires a procedure linkage table entry. We
519 actually build the entry in adjust_dynamic_symbol,
520 because this might be a case of linking PIC code without
521 linking in any dynamic objects, in which case we don't
522 need to generate a procedure linkage table after all. */
523
524 /* If this is a local symbol, we resolve it directly without
525 creating a procedure linkage table entry. */
526 if (h == NULL)
527 continue;
528
529 /* Make sure this symbol is output as a dynamic symbol. */
530 if (h->dynindx == -1)
531 {
532 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
533 return false;
534 }
535
536 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
537
538 break;
539
540 case R_386_32:
541 case R_386_PC32:
542 if (info->shared
543 && (sec->flags & SEC_ALLOC) != 0)
544 {
545 /* When creating a shared object, we must output a
546 R_386_RELATIVE reloc for this location. We create a
547 reloc section in dynobj and make room for this reloc. */
548 if (sreloc == NULL)
549 {
550 const char *name;
551
552 name = (elf_string_from_elf_section
553 (abfd,
554 elf_elfheader (abfd)->e_shstrndx,
555 elf_section_data (sec)->rel_hdr.sh_name));
556 if (name == NULL)
557 return false;
558
559 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
560 && strcmp (bfd_get_section_name (abfd, sec),
561 name + 4) == 0);
562
563 sreloc = bfd_get_section_by_name (dynobj, name);
564 if (sreloc == NULL)
565 {
566 sreloc = bfd_make_section (dynobj, name);
567 if (sreloc == NULL
568 || ! bfd_set_section_flags (dynobj, sreloc,
569 (SEC_ALLOC
570 | SEC_LOAD
571 | SEC_HAS_CONTENTS
572 | SEC_IN_MEMORY
573 | SEC_READONLY))
574 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
575 return false;
576 }
577 }
578
579 sreloc->_raw_size += sizeof (Elf32_External_Rel);
580 }
581
582 break;
583
584 default:
585 break;
586 }
587 }
588
589 return true;
590 }
591
592 /* Adjust a symbol defined by a dynamic object and referenced by a
593 regular object. The current definition is in some section of the
594 dynamic object, but we're not including those sections. We have to
595 change the definition to something the rest of the link can
596 understand. */
597
598 static boolean
599 elf_i386_adjust_dynamic_symbol (info, h)
600 struct bfd_link_info *info;
601 struct elf_link_hash_entry *h;
602 {
603 bfd *dynobj;
604 asection *s;
605 unsigned int power_of_two;
606
607 dynobj = elf_hash_table (info)->dynobj;
608
609 /* Make sure we know what is going on here. */
610 BFD_ASSERT (dynobj != NULL
611 && h->root.type == bfd_link_hash_defined
612 && (bfd_get_flavour (h->root.u.def.section->owner)
613 == bfd_target_elf_flavour)
614 && ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT)
615 || ((h->elf_link_hash_flags
616 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
617 && (h->elf_link_hash_flags
618 & ELF_LINK_HASH_REF_REGULAR) != 0
619 && (h->elf_link_hash_flags
620 & ELF_LINK_HASH_DEF_REGULAR) == 0
621 && (elf_elfheader (h->root.u.def.section->owner)->e_type
622 == ET_DYN)
623 && h->root.u.def.section->output_section == NULL)));
624
625 /* If this is a function, put it in the procedure linkage table. We
626 will fill in the contents of the procedure linkage table later,
627 when we know the address of the .got section. */
628 if (h->type == STT_FUNC
629 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
630 {
631 if (! elf_hash_table (info)->dynamic_sections_created)
632 {
633 /* This case can occur if we saw a PLT32 reloc in an input
634 file, but none of the input files were dynamic objects.
635 In such a case, we don't actually need to build a
636 procedure linkage table, and we can just do a PC32 reloc
637 instead. */
638 BFD_ASSERT ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0);
639 return true;
640 }
641
642 s = bfd_get_section_by_name (dynobj, ".plt");
643 BFD_ASSERT (s != NULL);
644
645 /* If this is the first .plt entry, make room for the special
646 first entry. */
647 if (s->_raw_size == 0)
648 s->_raw_size += PLT_ENTRY_SIZE;
649
650 /* Set the symbol to this location in the .plt. */
651 h->root.u.def.section = s;
652 h->root.u.def.value = s->_raw_size;
653
654 h->plt_offset = s->_raw_size;
655
656 /* Make room for this entry. */
657 s->_raw_size += PLT_ENTRY_SIZE;
658
659 /* We also need to make an entry in the .got.plt section, which
660 will be placed in the .got section by the linker script. */
661
662 s = bfd_get_section_by_name (dynobj, ".got.plt");
663 BFD_ASSERT (s != NULL);
664 s->_raw_size += 4;
665
666 /* We also need to make an entry in the .rel.plt section. */
667
668 s = bfd_get_section_by_name (dynobj, ".rel.plt");
669 BFD_ASSERT (s != NULL);
670 s->_raw_size += sizeof (Elf32_External_Rel);
671
672 return true;
673 }
674
675 /* If this is a weak symbol, and there is a real definition, the
676 processor independent code will have arranged for us to see the
677 real definition first, and we can just use the same value. */
678 if (h->weakdef != NULL)
679 {
680 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined);
681 h->root.u.def.section = h->weakdef->root.u.def.section;
682 h->root.u.def.value = h->weakdef->root.u.def.value;
683 return true;
684 }
685
686 /* This is a reference to a symbol defined by a dynamic object which
687 is not a function. */
688
689 /* If we are creating a shared library, we must presume that the
690 only references to the symbol are via the global offset table.
691 For such cases we need not do anything here; the relocations will
692 be handled correctly by relocate_section. */
693 if (info->shared)
694 return true;
695
696 /* We must allocate the symbol in our .dynbss section, which will
697 become part of the .bss section of the executable. There will be
698 an entry for this symbol in the .dynsym section. The dynamic
699 object will contain position independent code, so all references
700 from the dynamic object to this symbol will go through the global
701 offset table. The dynamic linker will use the .dynsym entry to
702 determine the address it must put in the global offset table, so
703 both the dynamic object and the regular object will refer to the
704 same memory location for the variable. */
705
706 s = bfd_get_section_by_name (dynobj, ".dynbss");
707 BFD_ASSERT (s != NULL);
708
709 /* If the symbol is currently defined in the .bss section of the
710 dynamic object, then it is OK to simply initialize it to zero.
711 If the symbol is in some other section, we must generate a
712 R_386_COPY reloc to tell the dynamic linker to copy the initial
713 value out of the dynamic object and into the runtime process
714 image. We need to remember the offset into the .rel.bss section
715 we are going to use. */
716 if ((h->root.u.def.section->flags & SEC_LOAD) != 0)
717 {
718 asection *srel;
719
720 srel = bfd_get_section_by_name (dynobj, ".rel.bss");
721 BFD_ASSERT (srel != NULL);
722 srel->_raw_size += sizeof (Elf32_External_Rel);
723 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
724 }
725
726 /* We need to figure out the alignment required for this symbol. I
727 have no idea how ELF linkers handle this. */
728 power_of_two = bfd_log2 (h->size);
729 if (power_of_two > 3)
730 power_of_two = 3;
731
732 /* Apply the required alignment. */
733 s->_raw_size = BFD_ALIGN (s->_raw_size,
734 (bfd_size_type) (1 << power_of_two));
735 if (power_of_two > bfd_get_section_alignment (dynobj, s))
736 {
737 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
738 return false;
739 }
740
741 /* Define the symbol as being at this point in the section. */
742 h->root.u.def.section = s;
743 h->root.u.def.value = s->_raw_size;
744
745 /* Increment the section size to make room for the symbol. */
746 s->_raw_size += h->size;
747
748 return true;
749 }
750
751 /* Set the sizes of the dynamic sections. */
752
753 static boolean
754 elf_i386_size_dynamic_sections (output_bfd, info)
755 bfd *output_bfd;
756 struct bfd_link_info *info;
757 {
758 bfd *dynobj;
759 asection *s;
760 boolean plt;
761 boolean relocs;
762 boolean reltext;
763
764 dynobj = elf_hash_table (info)->dynobj;
765 BFD_ASSERT (dynobj != NULL);
766
767 if (elf_hash_table (info)->dynamic_sections_created)
768 {
769 /* Set the contents of the .interp section to the interpreter. */
770 if (! info->shared)
771 {
772 s = bfd_get_section_by_name (dynobj, ".interp");
773 BFD_ASSERT (s != NULL);
774 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
775 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
776 }
777 }
778 else
779 {
780 /* We may have created entries in the .rel.got section.
781 However, if we are not creating the dynamic sections, we will
782 not actually use these entries. Reset the size of .rel.got,
783 which will cause it to get stripped from the output file
784 below. */
785 s = bfd_get_section_by_name (dynobj, ".rel.got");
786 if (s != NULL)
787 s->_raw_size = 0;
788 }
789
790 /* The check_relocs and adjust_dynamic_symbol entry points have
791 determined the sizes of the various dynamic sections. Allocate
792 memory for them. */
793 plt = false;
794 relocs = false;
795 reltext = false;
796 for (s = dynobj->sections; s != NULL; s = s->next)
797 {
798 const char *name;
799 boolean strip;
800
801 if ((s->flags & SEC_IN_MEMORY) == 0)
802 continue;
803
804 /* It's OK to base decisions on the section name, because none
805 of the dynobj section names depend upon the input files. */
806 name = bfd_get_section_name (dynobj, s);
807
808 strip = false;
809
810 if (strcmp (name, ".plt") == 0)
811 {
812 if (s->_raw_size == 0)
813 {
814 /* Strip this section if we don't need it; see the
815 comment below. */
816 strip = true;
817 }
818 else
819 {
820 /* Remember whether there is a PLT. */
821 plt = true;
822 }
823 }
824 else if (strncmp (name, ".rel", 4) == 0)
825 {
826 if (s->_raw_size == 0)
827 {
828 /* If we don't need this section, strip it from the
829 output file. This is mostly to handle .rel.bss and
830 .rel.plt. We must create both sections in
831 create_dynamic_sections, because they must be created
832 before the linker maps input sections to output
833 sections. The linker does that before
834 adjust_dynamic_symbol is called, and it is that
835 function which decides whether anything needs to go
836 into these sections. */
837 strip = true;
838 }
839 else
840 {
841 asection *target;
842
843 /* Remember whether there are any reloc sections other
844 than .rel.plt. */
845 if (strcmp (name, ".rel.plt") != 0)
846 relocs = true;
847
848 /* If this relocation section applies to a read only
849 section, then we probably need a DT_TEXTREL entry. */
850 target = bfd_get_section_by_name (output_bfd, name + 4);
851 if (target != NULL
852 && (target->flags & SEC_READONLY) != 0)
853 reltext = true;
854
855 /* We use the reloc_count field as a counter if we need
856 to copy relocs into the output file. */
857 s->reloc_count = 0;
858 }
859 }
860 else if (strncmp (name, ".got", 4) != 0)
861 {
862 /* It's not one of our sections, so don't allocate space. */
863 continue;
864 }
865
866 if (strip)
867 {
868 asection **spp;
869
870 for (spp = &s->output_section->owner->sections;
871 *spp != s->output_section;
872 spp = &(*spp)->next)
873 ;
874 *spp = s->output_section->next;
875 --s->output_section->owner->section_count;
876
877 continue;
878 }
879
880 /* Allocate memory for the section contents. */
881 s->contents = (bfd_byte *) bfd_alloc (dynobj, s->_raw_size);
882 if (s->contents == NULL && s->_raw_size != 0)
883 {
884 bfd_set_error (bfd_error_no_memory);
885 return false;
886 }
887 }
888
889 if (elf_hash_table (info)->dynamic_sections_created)
890 {
891 /* Add some entries to the .dynamic section. We fill in the
892 values later, in elf_i386_finish_dynamic_sections, but we
893 must add the entries now so that we get the correct size for
894 the .dynamic section. The DT_DEBUG entry is filled in by the
895 dynamic linker and used by the debugger. */
896 if (! info->shared)
897 {
898 if (! bfd_elf32_add_dynamic_entry (info, DT_DEBUG, 0))
899 return false;
900 }
901
902 if (plt)
903 {
904 if (! bfd_elf32_add_dynamic_entry (info, DT_PLTGOT, 0)
905 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTRELSZ, 0)
906 || ! bfd_elf32_add_dynamic_entry (info, DT_PLTREL, DT_REL)
907 || ! bfd_elf32_add_dynamic_entry (info, DT_JMPREL, 0))
908 return false;
909 }
910
911 if (relocs)
912 {
913 if (! bfd_elf32_add_dynamic_entry (info, DT_REL, 0)
914 || ! bfd_elf32_add_dynamic_entry (info, DT_RELSZ, 0)
915 || ! bfd_elf32_add_dynamic_entry (info, DT_RELENT,
916 sizeof (Elf32_External_Rel)))
917 return false;
918 }
919
920 if (reltext)
921 {
922 if (! bfd_elf32_add_dynamic_entry (info, DT_TEXTREL, 0))
923 return false;
924 }
925 }
926
927 return true;
928 }
929
930 /* Relocate an i386 ELF section. */
931
932 static boolean
933 elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
934 contents, relocs, local_syms, local_sections)
935 bfd *output_bfd;
936 struct bfd_link_info *info;
937 bfd *input_bfd;
938 asection *input_section;
939 bfd_byte *contents;
940 Elf_Internal_Rela *relocs;
941 Elf_Internal_Sym *local_syms;
942 asection **local_sections;
943 {
944 bfd *dynobj;
945 Elf_Internal_Shdr *symtab_hdr;
946 struct elf_link_hash_entry **sym_hashes;
947 bfd_vma *local_got_offsets;
948 asection *sgot;
949 asection *splt;
950 asection *sreloc;
951 Elf_Internal_Rela *rel;
952 Elf_Internal_Rela *relend;
953
954 dynobj = elf_hash_table (info)->dynobj;
955 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
956 sym_hashes = elf_sym_hashes (input_bfd);
957 local_got_offsets = elf_local_got_offsets (input_bfd);
958
959 sgot = NULL;
960 splt = NULL;
961 sreloc = NULL;
962
963 rel = relocs;
964 relend = relocs + input_section->reloc_count;
965 for (; rel < relend; rel++)
966 {
967 int r_type;
968 const reloc_howto_type *howto;
969 long r_symndx;
970 struct elf_link_hash_entry *h;
971 Elf_Internal_Sym *sym;
972 asection *sec;
973 bfd_vma relocation;
974 bfd_reloc_status_type r;
975
976 r_type = ELF32_R_TYPE (rel->r_info);
977 if (r_type < 0 || r_type >= (int) R_386_max)
978 {
979 bfd_set_error (bfd_error_bad_value);
980 return false;
981 }
982 howto = elf_howto_table + r_type;
983
984 r_symndx = ELF32_R_SYM (rel->r_info);
985
986 if (info->relocateable)
987 {
988 /* This is a relocateable link. We don't have to change
989 anything, unless the reloc is against a section symbol,
990 in which case we have to adjust according to where the
991 section symbol winds up in the output section. */
992 if (r_symndx < symtab_hdr->sh_info)
993 {
994 sym = local_syms + r_symndx;
995 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
996 {
997 bfd_vma val;
998
999 sec = local_sections[r_symndx];
1000 val = bfd_get_32 (input_bfd, contents + rel->r_offset);
1001 val += sec->output_offset + sym->st_value;
1002 bfd_put_32 (input_bfd, val, contents + rel->r_offset);
1003 }
1004 }
1005
1006 continue;
1007 }
1008
1009 /* This is a final link. */
1010 h = NULL;
1011 sym = NULL;
1012 sec = NULL;
1013 if (r_symndx < symtab_hdr->sh_info)
1014 {
1015 sym = local_syms + r_symndx;
1016 sec = local_sections[r_symndx];
1017 relocation = (sec->output_section->vma
1018 + sec->output_offset
1019 + sym->st_value);
1020 }
1021 else
1022 {
1023 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1024 if (h->root.type == bfd_link_hash_defined)
1025 {
1026 sec = h->root.u.def.section;
1027 relocation = (h->root.u.def.value
1028 + sec->output_section->vma
1029 + sec->output_offset);
1030 }
1031 else if (h->root.type == bfd_link_hash_weak)
1032 relocation = 0;
1033 else if (info->shared)
1034 relocation = 0;
1035 else
1036 {
1037 if (! ((*info->callbacks->undefined_symbol)
1038 (info, h->root.root.string, input_bfd,
1039 input_section, rel->r_offset)))
1040 return false;
1041 relocation = 0;
1042 }
1043 }
1044
1045 switch (r_type)
1046 {
1047 case R_386_GOT32:
1048 /* Relocation is to the entry for this symbol in the global
1049 offset table. */
1050 if (sgot == NULL)
1051 {
1052 sgot = bfd_get_section_by_name (dynobj, ".got");
1053 BFD_ASSERT (sgot != NULL);
1054 }
1055
1056 if (h != NULL)
1057 {
1058 bfd_vma off;
1059
1060 off = h->got_offset;
1061 BFD_ASSERT (off != (bfd_vma) -1);
1062
1063 if (! elf_hash_table (info)->dynamic_sections_created)
1064 {
1065 /* This is actually a static link. We must
1066 initialize this entry in the global offset table.
1067 Since the offset must always be a multiple of 4,
1068 we use the least significant bit to record
1069 whether we have initialized it already.
1070
1071 When doing a dynamic link, we create a .rel.got
1072 relocation entry to initialize the value. This
1073 is done in the finish_dynamic_symbol routine. */
1074 if ((off & 1) != 0)
1075 off &= ~1;
1076 else
1077 {
1078 bfd_put_32 (output_bfd, relocation,
1079 sgot->contents + off);
1080 h->got_offset |= 1;
1081 }
1082 }
1083
1084 relocation = sgot->output_offset + off;
1085 }
1086 else
1087 {
1088 bfd_vma off;
1089
1090 BFD_ASSERT (local_got_offsets != NULL
1091 && local_got_offsets[r_symndx] != (bfd_vma) -1);
1092
1093 off = local_got_offsets[r_symndx];
1094
1095 /* The offset must always be a multiple of 4. We use
1096 the least significant bit to record whether we have
1097 already generated the necessary reloc. */
1098 if ((off & 1) != 0)
1099 off &= ~1;
1100 else
1101 {
1102 bfd_put_32 (output_bfd, relocation, sgot->contents + off);
1103
1104 if (info->shared)
1105 {
1106 asection *srelgot;
1107 Elf_Internal_Rel outrel;
1108
1109 srelgot = bfd_get_section_by_name (dynobj, ".rel.got");
1110 BFD_ASSERT (srelgot != NULL);
1111
1112 outrel.r_offset = (sgot->output_section->vma
1113 + sgot->output_offset
1114 + off);
1115 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1116 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1117 (((Elf32_External_Rel *)
1118 srelgot->contents)
1119 + srelgot->reloc_count));
1120 ++srelgot->reloc_count;
1121 }
1122
1123 local_got_offsets[r_symndx] |= 1;
1124 }
1125
1126 relocation = sgot->output_offset + off;
1127 }
1128
1129 break;
1130
1131 case R_386_GOTOFF:
1132 /* Relocation is relative to the start of the global offset
1133 table. */
1134
1135 if (sgot == NULL)
1136 {
1137 sgot = bfd_get_section_by_name (dynobj, ".got");
1138 BFD_ASSERT (sgot != NULL);
1139 }
1140
1141 /* Note that sgot->output_offset is not involved in this
1142 calculation. We always want the start of .got. If we
1143 defined _GLOBAL_OFFSET_TABLE in a different way, as is
1144 permitted by the ABI, we might have to change this
1145 calculation. */
1146 relocation -= sgot->output_section->vma;
1147
1148 break;
1149
1150 case R_386_GOTPC:
1151 /* Use global offset table as symbol value. */
1152
1153 if (sgot == NULL)
1154 {
1155 sgot = bfd_get_section_by_name (dynobj, ".got");
1156 BFD_ASSERT (sgot != NULL);
1157 }
1158
1159 relocation = sgot->output_section->vma;
1160
1161 break;
1162
1163 case R_386_PLT32:
1164 /* Relocation is to the entry for this symbol in the
1165 procedure linkage table. */
1166
1167 /* Resolve a PLT32 reloc again a local symbol directly,
1168 without using the procedure linkage table. */
1169 if (h == NULL)
1170 break;
1171
1172 if (h->plt_offset == (bfd_vma) -1)
1173 {
1174 /* We didn't make a PLT entry for this symbol. This
1175 happens when statically linking PIC code. */
1176 break;
1177 }
1178
1179 if (splt == NULL)
1180 {
1181 splt = bfd_get_section_by_name (dynobj, ".plt");
1182 BFD_ASSERT (splt != NULL);
1183 }
1184
1185 relocation = (splt->output_section->vma
1186 + splt->output_offset
1187 + h->plt_offset);
1188
1189 break;
1190
1191 case R_386_32:
1192 case R_386_PC32:
1193 if (info->shared
1194 && (input_section->flags & SEC_ALLOC) != 0)
1195 {
1196 Elf_Internal_Rel outrel;
1197
1198 /* When generating a shared object, these relocations
1199 are copied into the output file to be resolved at run
1200 time. */
1201
1202 if (sreloc == NULL)
1203 {
1204 const char *name;
1205
1206 name = (elf_string_from_elf_section
1207 (input_bfd,
1208 elf_elfheader (input_bfd)->e_shstrndx,
1209 elf_section_data (input_section)->rel_hdr.sh_name));
1210 if (name == NULL)
1211 return false;
1212
1213 BFD_ASSERT (strncmp (name, ".rel", 4) == 0
1214 && strcmp (bfd_get_section_name (input_bfd,
1215 input_section),
1216 name + 4) == 0);
1217
1218 sreloc = bfd_get_section_by_name (dynobj, name);
1219 BFD_ASSERT (sreloc != NULL);
1220 }
1221
1222 outrel.r_offset = (rel->r_offset
1223 + input_section->output_section->vma
1224 + input_section->output_offset);
1225 if (r_type == R_386_PC32)
1226 {
1227 BFD_ASSERT (h != NULL && h->dynindx != -1);
1228 outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_PC32);
1229 }
1230 else
1231 {
1232 if (h == NULL)
1233 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1234 else
1235 {
1236 BFD_ASSERT (h->dynindx != (bfd_vma) -1);
1237 outrel.r_info = ELF32_R_INFO (h->dynindx, R_386_32);
1238 }
1239 }
1240
1241 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1242 (((Elf32_External_Rel *)
1243 sreloc->contents)
1244 + sreloc->reloc_count));
1245 ++sreloc->reloc_count;
1246
1247 /* If this reloc is against an external symbol, we do
1248 not want to fiddle with the addend. Otherwise, we
1249 need to include the symbol value so that it becomes
1250 an addend for the dynamic reloc. */
1251 if (h != NULL)
1252 continue;
1253 }
1254
1255 break;
1256
1257 default:
1258 break;
1259 }
1260
1261 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
1262 contents, rel->r_offset,
1263 relocation, (bfd_vma) 0);
1264
1265 if (r != bfd_reloc_ok)
1266 {
1267 switch (r)
1268 {
1269 default:
1270 case bfd_reloc_outofrange:
1271 abort ();
1272 case bfd_reloc_overflow:
1273 {
1274 const char *name;
1275
1276 if (h != NULL)
1277 name = h->root.root.string;
1278 else
1279 {
1280 name = elf_string_from_elf_section (input_bfd,
1281 symtab_hdr->sh_link,
1282 sym->st_name);
1283 if (name == NULL)
1284 return false;
1285 if (*name == '\0')
1286 name = bfd_section_name (input_bfd, sec);
1287 }
1288 if (! ((*info->callbacks->reloc_overflow)
1289 (info, name, howto->name, (bfd_vma) 0,
1290 input_bfd, input_section, rel->r_offset)))
1291 return false;
1292 }
1293 break;
1294 }
1295 }
1296 }
1297
1298 return true;
1299 }
1300
1301 /* Finish up dynamic symbol handling. We set the contents of various
1302 dynamic sections here. */
1303
1304 static boolean
1305 elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
1306 bfd *output_bfd;
1307 struct bfd_link_info *info;
1308 struct elf_link_hash_entry *h;
1309 Elf_Internal_Sym *sym;
1310 {
1311 bfd *dynobj;
1312
1313 dynobj = elf_hash_table (info)->dynobj;
1314
1315 if (h->plt_offset != (bfd_vma) -1)
1316 {
1317 asection *splt;
1318 asection *sgot;
1319 asection *srel;
1320 bfd_vma plt_index;
1321 bfd_vma got_offset;
1322 Elf_Internal_Rel rel;
1323
1324 /* This symbol has an entry in the procedure linkage table. Set
1325 it up. */
1326
1327 BFD_ASSERT (h->dynindx != -1);
1328
1329 splt = bfd_get_section_by_name (dynobj, ".plt");
1330 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1331 srel = bfd_get_section_by_name (dynobj, ".rel.plt");
1332 BFD_ASSERT (splt != NULL && sgot != NULL && srel != NULL);
1333
1334 /* Get the index in the procedure linkage table which
1335 corresponds to this symbol. This is the index of this symbol
1336 in all the symbols for which we are making plt entries. The
1337 first entry in the procedure linkage table is reserved. */
1338 plt_index = h->plt_offset / PLT_ENTRY_SIZE - 1;
1339
1340 /* Get the offset into the .got table of the entry that
1341 corresponds to this function. Each .got entry is 4 bytes.
1342 The first three are reserved. */
1343 got_offset = (plt_index + 3) * 4;
1344
1345 /* Fill in the entry in the procedure linkage table. */
1346 if (! info->shared)
1347 {
1348 memcpy (splt->contents + h->plt_offset, elf_i386_plt_entry,
1349 PLT_ENTRY_SIZE);
1350 bfd_put_32 (output_bfd,
1351 (sgot->output_section->vma
1352 + sgot->output_offset
1353 + got_offset),
1354 splt->contents + h->plt_offset + 2);
1355 }
1356 else
1357 {
1358 memcpy (splt->contents + h->plt_offset, elf_i386_pic_plt_entry,
1359 PLT_ENTRY_SIZE);
1360 bfd_put_32 (output_bfd, got_offset,
1361 splt->contents + h->plt_offset + 2);
1362 }
1363
1364 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
1365 splt->contents + h->plt_offset + 7);
1366 bfd_put_32 (output_bfd, - (h->plt_offset + PLT_ENTRY_SIZE),
1367 splt->contents + h->plt_offset + 12);
1368
1369 /* Fill in the entry in the global offset table. */
1370 bfd_put_32 (output_bfd,
1371 (splt->output_section->vma
1372 + splt->output_offset
1373 + h->plt_offset
1374 + 6),
1375 sgot->contents + got_offset);
1376
1377 /* Fill in the entry in the .rel.plt section. */
1378 rel.r_offset = (sgot->output_section->vma
1379 + sgot->output_offset
1380 + got_offset);
1381 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
1382 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1383 ((Elf32_External_Rel *) srel->contents
1384 + plt_index));
1385
1386 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1387 {
1388 /* Mark the symbol as undefined, rather than as defined in
1389 the .plt section. Leave the value alone. */
1390 sym->st_shndx = SHN_UNDEF;
1391 }
1392 }
1393
1394 if (h->got_offset != (bfd_vma) -1)
1395 {
1396 asection *sgot;
1397 asection *srel;
1398 Elf_Internal_Rel rel;
1399
1400 /* This symbol has an entry in the global offset table. Set it
1401 up. */
1402
1403 BFD_ASSERT (h->dynindx != -1);
1404
1405 sgot = bfd_get_section_by_name (dynobj, ".got");
1406 srel = bfd_get_section_by_name (dynobj, ".rel.got");
1407 BFD_ASSERT (sgot != NULL && srel != NULL);
1408
1409 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + h->got_offset);
1410
1411 rel.r_offset = (sgot->output_section->vma
1412 + sgot->output_offset
1413 + h->got_offset);
1414 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
1415 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1416 ((Elf32_External_Rel *) srel->contents
1417 + srel->reloc_count));
1418 ++srel->reloc_count;
1419 }
1420
1421 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
1422 {
1423 asection *s;
1424 Elf_Internal_Rel rel;
1425
1426 /* This symbol needs a copy reloc. Set it up. */
1427
1428 BFD_ASSERT (h->dynindx != -1
1429 && h->root.type == bfd_link_hash_defined);
1430
1431 s = bfd_get_section_by_name (h->root.u.def.section->owner,
1432 ".rel.bss");
1433 BFD_ASSERT (s != NULL);
1434
1435 rel.r_offset = (h->root.u.def.value
1436 + h->root.u.def.section->output_section->vma
1437 + h->root.u.def.section->output_offset);
1438 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
1439 bfd_elf32_swap_reloc_out (output_bfd, &rel,
1440 ((Elf32_External_Rel *) s->contents
1441 + s->reloc_count));
1442 ++s->reloc_count;
1443 }
1444
1445 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
1446 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
1447 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
1448 sym->st_shndx = SHN_ABS;
1449
1450 return true;
1451 }
1452
1453 /* Finish up the dynamic sections. */
1454
1455 static boolean
1456 elf_i386_finish_dynamic_sections (output_bfd, info)
1457 bfd *output_bfd;
1458 struct bfd_link_info *info;
1459 {
1460 bfd *dynobj;
1461 asection *sgot;
1462 asection *sdyn;
1463
1464 dynobj = elf_hash_table (info)->dynobj;
1465
1466 sgot = bfd_get_section_by_name (dynobj, ".got.plt");
1467 BFD_ASSERT (sgot != NULL);
1468 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
1469
1470 if (elf_hash_table (info)->dynamic_sections_created)
1471 {
1472 asection *splt;
1473 Elf32_External_Dyn *dyncon, *dynconend;
1474
1475 splt = bfd_get_section_by_name (dynobj, ".plt");
1476 BFD_ASSERT (splt != NULL && sdyn != NULL);
1477
1478 dyncon = (Elf32_External_Dyn *) sdyn->contents;
1479 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
1480 for (; dyncon < dynconend; dyncon++)
1481 {
1482 Elf_Internal_Dyn dyn;
1483 const char *name;
1484 asection *s;
1485
1486 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
1487
1488 switch (dyn.d_tag)
1489 {
1490 default:
1491 break;
1492
1493 case DT_PLTGOT:
1494 name = ".got";
1495 goto get_vma;
1496 case DT_JMPREL:
1497 name = ".rel.plt";
1498 get_vma:
1499 s = bfd_get_section_by_name (output_bfd, name);
1500 BFD_ASSERT (s != NULL);
1501 dyn.d_un.d_ptr = s->vma;
1502 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1503 break;
1504
1505 case DT_PLTRELSZ:
1506 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
1507 BFD_ASSERT (s != NULL);
1508 if (s->_cooked_size != 0)
1509 dyn.d_un.d_val = s->_cooked_size;
1510 else
1511 dyn.d_un.d_val = s->_raw_size;
1512 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1513 break;
1514
1515 case DT_RELSZ:
1516 /* My reading of the SVR4 ABI indicates that the
1517 procedure linkage table relocs (DT_JMPREL) should be
1518 included in the overall relocs (DT_REL). This is
1519 what Solaris does. However, UnixWare can not handle
1520 that case. Therefore, we override the DT_RELSZ entry
1521 here to make it not include the JMPREL relocs. Since
1522 the linker script arranges for .rel.plt to follow all
1523 other relocation sections, we don't have to worry
1524 about changing the DT_REL entry. */
1525 s = bfd_get_section_by_name (output_bfd, ".rel.plt");
1526 if (s != NULL)
1527 {
1528 if (s->_cooked_size != 0)
1529 dyn.d_un.d_val -= s->_cooked_size;
1530 else
1531 dyn.d_un.d_val -= s->_raw_size;
1532 }
1533 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
1534 break;
1535 }
1536 }
1537
1538 /* Fill in the first entry in the procedure linkage table. */
1539 if (splt->_raw_size > 0)
1540 {
1541 if (info->shared)
1542 memcpy (splt->contents, elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
1543 else
1544 {
1545 memcpy (splt->contents, elf_i386_plt0_entry, PLT_ENTRY_SIZE);
1546 bfd_put_32 (output_bfd,
1547 sgot->output_section->vma + sgot->output_offset + 4,
1548 splt->contents + 2);
1549 bfd_put_32 (output_bfd,
1550 sgot->output_section->vma + sgot->output_offset + 8,
1551 splt->contents + 8);
1552 }
1553 }
1554
1555 /* UnixWare sets the entsize of .plt to 4, although that doesn't
1556 really seem like the right value. */
1557 elf_section_data (splt->output_section)->this_hdr.sh_entsize = 4;
1558 }
1559
1560 /* Fill in the first three entries in the global offset table. */
1561 if (sgot->_raw_size > 0)
1562 {
1563 if (sdyn == NULL)
1564 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents);
1565 else
1566 bfd_put_32 (output_bfd,
1567 sdyn->output_section->vma + sdyn->output_offset,
1568 sgot->contents);
1569 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 4);
1570 bfd_put_32 (output_bfd, (bfd_vma) 0, sgot->contents + 8);
1571 }
1572
1573 elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4;
1574
1575 return true;
1576 }
1577
1578 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
1579 #define TARGET_LITTLE_NAME "elf32-i386"
1580 #define ELF_ARCH bfd_arch_i386
1581 #define ELF_MACHINE_CODE EM_386
1582 #define elf_info_to_howto elf_i386_info_to_howto
1583 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
1584 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
1585 #define ELF_MAXPAGESIZE 0x1000
1586 #define elf_backend_create_dynamic_sections \
1587 elf_i386_create_dynamic_sections
1588 #define elf_backend_check_relocs elf_i386_check_relocs
1589 #define elf_backend_adjust_dynamic_symbol \
1590 elf_i386_adjust_dynamic_symbol
1591 #define elf_backend_size_dynamic_sections \
1592 elf_i386_size_dynamic_sections
1593 #define elf_backend_relocate_section elf_i386_relocate_section
1594 #define elf_backend_finish_dynamic_symbol \
1595 elf_i386_finish_dynamic_symbol
1596 #define elf_backend_finish_dynamic_sections \
1597 elf_i386_finish_dynamic_sections
1598
1599 #include "elf32-target.h"
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