* elf32-i386 (elf_i386_copy_indirect_symbol): New function.
[deliverable/binutils-gdb.git] / bfd / elf32-i386.c
1 /* Intel 80386/80486-specific support for 32-bit ELF
2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001
3 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26
27 static reloc_howto_type *elf_i386_reloc_type_lookup
28 PARAMS ((bfd *, bfd_reloc_code_real_type));
29 static void elf_i386_info_to_howto
30 PARAMS ((bfd *, arelent *, Elf32_Internal_Rela *));
31 static void elf_i386_info_to_howto_rel
32 PARAMS ((bfd *, arelent *, Elf32_Internal_Rel *));
33 static boolean elf_i386_is_local_label_name
34 PARAMS ((bfd *, const char *));
35 static boolean elf_i386_grok_prstatus
36 PARAMS ((bfd *abfd, Elf_Internal_Note *note));
37 static boolean elf_i386_grok_psinfo
38 PARAMS ((bfd *abfd, Elf_Internal_Note *note));
39 static struct bfd_hash_entry *link_hash_newfunc
40 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
41 static struct bfd_link_hash_table *elf_i386_link_hash_table_create
42 PARAMS ((bfd *));
43 static boolean create_got_section
44 PARAMS((bfd *, struct bfd_link_info *));
45 static boolean elf_i386_create_dynamic_sections
46 PARAMS((bfd *, struct bfd_link_info *));
47 static void
48 elf_i386_copy_indirect_symbol
49 PARAMS ((struct elf_link_hash_entry *, struct elf_link_hash_entry *));
50 static boolean elf_i386_check_relocs
51 PARAMS ((bfd *, struct bfd_link_info *, asection *,
52 const Elf_Internal_Rela *));
53 static asection *elf_i386_gc_mark_hook
54 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
55 struct elf_link_hash_entry *, Elf_Internal_Sym *));
56 static boolean elf_i386_gc_sweep_hook
57 PARAMS ((bfd *, struct bfd_link_info *, asection *,
58 const Elf_Internal_Rela *));
59 static boolean elf_i386_adjust_dynamic_symbol
60 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
61 static boolean allocate_dynrelocs
62 PARAMS ((struct elf_link_hash_entry *, PTR));
63 static boolean readonly_dynrelocs
64 PARAMS ((struct elf_link_hash_entry *, PTR));
65 static boolean elf_i386_fake_sections
66 PARAMS ((bfd *, Elf32_Internal_Shdr *, asection *));
67 static boolean elf_i386_size_dynamic_sections
68 PARAMS ((bfd *, struct bfd_link_info *));
69 static boolean elf_i386_relocate_section
70 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
71 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
72 static boolean elf_i386_finish_dynamic_symbol
73 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
74 Elf_Internal_Sym *));
75 static enum elf_reloc_type_class elf_i386_reloc_type_class
76 PARAMS ((const Elf_Internal_Rela *));
77 static boolean elf_i386_finish_dynamic_sections
78 PARAMS ((bfd *, struct bfd_link_info *));
79
80 #define USE_REL 1 /* 386 uses REL relocations instead of RELA */
81
82 #include "elf/i386.h"
83
84 static reloc_howto_type elf_howto_table[]=
85 {
86 HOWTO(R_386_NONE, 0, 0, 0, false, 0, complain_overflow_bitfield,
87 bfd_elf_generic_reloc, "R_386_NONE",
88 true, 0x00000000, 0x00000000, false),
89 HOWTO(R_386_32, 0, 2, 32, false, 0, complain_overflow_bitfield,
90 bfd_elf_generic_reloc, "R_386_32",
91 true, 0xffffffff, 0xffffffff, false),
92 HOWTO(R_386_PC32, 0, 2, 32, true, 0, complain_overflow_bitfield,
93 bfd_elf_generic_reloc, "R_386_PC32",
94 true, 0xffffffff, 0xffffffff, true),
95 HOWTO(R_386_GOT32, 0, 2, 32, false, 0, complain_overflow_bitfield,
96 bfd_elf_generic_reloc, "R_386_GOT32",
97 true, 0xffffffff, 0xffffffff, false),
98 HOWTO(R_386_PLT32, 0, 2, 32, true, 0, complain_overflow_bitfield,
99 bfd_elf_generic_reloc, "R_386_PLT32",
100 true, 0xffffffff, 0xffffffff, true),
101 HOWTO(R_386_COPY, 0, 2, 32, false, 0, complain_overflow_bitfield,
102 bfd_elf_generic_reloc, "R_386_COPY",
103 true, 0xffffffff, 0xffffffff, false),
104 HOWTO(R_386_GLOB_DAT, 0, 2, 32, false, 0, complain_overflow_bitfield,
105 bfd_elf_generic_reloc, "R_386_GLOB_DAT",
106 true, 0xffffffff, 0xffffffff, false),
107 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, false, 0, complain_overflow_bitfield,
108 bfd_elf_generic_reloc, "R_386_JUMP_SLOT",
109 true, 0xffffffff, 0xffffffff, false),
110 HOWTO(R_386_RELATIVE, 0, 2, 32, false, 0, complain_overflow_bitfield,
111 bfd_elf_generic_reloc, "R_386_RELATIVE",
112 true, 0xffffffff, 0xffffffff, false),
113 HOWTO(R_386_GOTOFF, 0, 2, 32, false, 0, complain_overflow_bitfield,
114 bfd_elf_generic_reloc, "R_386_GOTOFF",
115 true, 0xffffffff, 0xffffffff, false),
116 HOWTO(R_386_GOTPC, 0, 2, 32, true, 0, complain_overflow_bitfield,
117 bfd_elf_generic_reloc, "R_386_GOTPC",
118 true, 0xffffffff, 0xffffffff, true),
119
120 /* We have a gap in the reloc numbers here.
121 R_386_standard counts the number up to this point, and
122 R_386_ext_offset is the value to subtract from a reloc type of
123 R_386_16 thru R_386_PC8 to form an index into this table. */
124 #define R_386_standard ((unsigned int) R_386_GOTPC + 1)
125 #define R_386_ext_offset ((unsigned int) R_386_16 - R_386_standard)
126
127 /* The remaining relocs are a GNU extension. */
128 HOWTO(R_386_16, 0, 1, 16, false, 0, complain_overflow_bitfield,
129 bfd_elf_generic_reloc, "R_386_16",
130 true, 0xffff, 0xffff, false),
131 HOWTO(R_386_PC16, 0, 1, 16, true, 0, complain_overflow_bitfield,
132 bfd_elf_generic_reloc, "R_386_PC16",
133 true, 0xffff, 0xffff, true),
134 HOWTO(R_386_8, 0, 0, 8, false, 0, complain_overflow_bitfield,
135 bfd_elf_generic_reloc, "R_386_8",
136 true, 0xff, 0xff, false),
137 HOWTO(R_386_PC8, 0, 0, 8, true, 0, complain_overflow_signed,
138 bfd_elf_generic_reloc, "R_386_PC8",
139 true, 0xff, 0xff, true),
140
141 /* Another gap. */
142 #define R_386_ext ((unsigned int) R_386_PC8 + 1 - R_386_ext_offset)
143 #define R_386_vt_offset ((unsigned int) R_386_GNU_VTINHERIT - R_386_ext)
144
145 /* GNU extension to record C++ vtable hierarchy. */
146 HOWTO (R_386_GNU_VTINHERIT, /* type */
147 0, /* rightshift */
148 2, /* size (0 = byte, 1 = short, 2 = long) */
149 0, /* bitsize */
150 false, /* pc_relative */
151 0, /* bitpos */
152 complain_overflow_dont, /* complain_on_overflow */
153 NULL, /* special_function */
154 "R_386_GNU_VTINHERIT", /* name */
155 false, /* partial_inplace */
156 0, /* src_mask */
157 0, /* dst_mask */
158 false),
159
160 /* GNU extension to record C++ vtable member usage. */
161 HOWTO (R_386_GNU_VTENTRY, /* type */
162 0, /* rightshift */
163 2, /* size (0 = byte, 1 = short, 2 = long) */
164 0, /* bitsize */
165 false, /* pc_relative */
166 0, /* bitpos */
167 complain_overflow_dont, /* complain_on_overflow */
168 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
169 "R_386_GNU_VTENTRY", /* name */
170 false, /* partial_inplace */
171 0, /* src_mask */
172 0, /* dst_mask */
173 false)
174
175 #define R_386_vt ((unsigned int) R_386_GNU_VTENTRY + 1 - R_386_vt_offset)
176
177 };
178
179 #ifdef DEBUG_GEN_RELOC
180 #define TRACE(str) fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
181 #else
182 #define TRACE(str)
183 #endif
184
185 static reloc_howto_type *
186 elf_i386_reloc_type_lookup (abfd, code)
187 bfd *abfd ATTRIBUTE_UNUSED;
188 bfd_reloc_code_real_type code;
189 {
190 switch (code)
191 {
192 case BFD_RELOC_NONE:
193 TRACE ("BFD_RELOC_NONE");
194 return &elf_howto_table[(unsigned int) R_386_NONE ];
195
196 case BFD_RELOC_32:
197 TRACE ("BFD_RELOC_32");
198 return &elf_howto_table[(unsigned int) R_386_32 ];
199
200 case BFD_RELOC_CTOR:
201 TRACE ("BFD_RELOC_CTOR");
202 return &elf_howto_table[(unsigned int) R_386_32 ];
203
204 case BFD_RELOC_32_PCREL:
205 TRACE ("BFD_RELOC_PC32");
206 return &elf_howto_table[(unsigned int) R_386_PC32 ];
207
208 case BFD_RELOC_386_GOT32:
209 TRACE ("BFD_RELOC_386_GOT32");
210 return &elf_howto_table[(unsigned int) R_386_GOT32 ];
211
212 case BFD_RELOC_386_PLT32:
213 TRACE ("BFD_RELOC_386_PLT32");
214 return &elf_howto_table[(unsigned int) R_386_PLT32 ];
215
216 case BFD_RELOC_386_COPY:
217 TRACE ("BFD_RELOC_386_COPY");
218 return &elf_howto_table[(unsigned int) R_386_COPY ];
219
220 case BFD_RELOC_386_GLOB_DAT:
221 TRACE ("BFD_RELOC_386_GLOB_DAT");
222 return &elf_howto_table[(unsigned int) R_386_GLOB_DAT ];
223
224 case BFD_RELOC_386_JUMP_SLOT:
225 TRACE ("BFD_RELOC_386_JUMP_SLOT");
226 return &elf_howto_table[(unsigned int) R_386_JUMP_SLOT ];
227
228 case BFD_RELOC_386_RELATIVE:
229 TRACE ("BFD_RELOC_386_RELATIVE");
230 return &elf_howto_table[(unsigned int) R_386_RELATIVE ];
231
232 case BFD_RELOC_386_GOTOFF:
233 TRACE ("BFD_RELOC_386_GOTOFF");
234 return &elf_howto_table[(unsigned int) R_386_GOTOFF ];
235
236 case BFD_RELOC_386_GOTPC:
237 TRACE ("BFD_RELOC_386_GOTPC");
238 return &elf_howto_table[(unsigned int) R_386_GOTPC ];
239
240 /* The remaining relocs are a GNU extension. */
241 case BFD_RELOC_16:
242 TRACE ("BFD_RELOC_16");
243 return &elf_howto_table[(unsigned int) R_386_16 - R_386_ext_offset];
244
245 case BFD_RELOC_16_PCREL:
246 TRACE ("BFD_RELOC_16_PCREL");
247 return &elf_howto_table[(unsigned int) R_386_PC16 - R_386_ext_offset];
248
249 case BFD_RELOC_8:
250 TRACE ("BFD_RELOC_8");
251 return &elf_howto_table[(unsigned int) R_386_8 - R_386_ext_offset];
252
253 case BFD_RELOC_8_PCREL:
254 TRACE ("BFD_RELOC_8_PCREL");
255 return &elf_howto_table[(unsigned int) R_386_PC8 - R_386_ext_offset];
256
257 case BFD_RELOC_VTABLE_INHERIT:
258 TRACE ("BFD_RELOC_VTABLE_INHERIT");
259 return &elf_howto_table[(unsigned int) R_386_GNU_VTINHERIT
260 - R_386_vt_offset];
261
262 case BFD_RELOC_VTABLE_ENTRY:
263 TRACE ("BFD_RELOC_VTABLE_ENTRY");
264 return &elf_howto_table[(unsigned int) R_386_GNU_VTENTRY
265 - R_386_vt_offset];
266
267 default:
268 break;
269 }
270
271 TRACE ("Unknown");
272 return 0;
273 }
274
275 static void
276 elf_i386_info_to_howto (abfd, cache_ptr, dst)
277 bfd *abfd ATTRIBUTE_UNUSED;
278 arelent *cache_ptr ATTRIBUTE_UNUSED;
279 Elf32_Internal_Rela *dst ATTRIBUTE_UNUSED;
280 {
281 abort ();
282 }
283
284 static void
285 elf_i386_info_to_howto_rel (abfd, cache_ptr, dst)
286 bfd *abfd ATTRIBUTE_UNUSED;
287 arelent *cache_ptr;
288 Elf32_Internal_Rel *dst;
289 {
290 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
291 unsigned int indx;
292
293 if ((indx = r_type) >= R_386_standard
294 && ((indx = r_type - R_386_ext_offset) - R_386_standard
295 >= R_386_ext - R_386_standard)
296 && ((indx = r_type - R_386_vt_offset) - R_386_ext
297 >= R_386_vt - R_386_ext))
298 {
299 (*_bfd_error_handler) (_("%s: invalid relocation type %d"),
300 bfd_archive_filename (abfd), (int) r_type);
301 indx = (unsigned int) R_386_NONE;
302 }
303 cache_ptr->howto = &elf_howto_table[indx];
304 }
305
306 /* Return whether a symbol name implies a local label. The UnixWare
307 2.1 cc generates temporary symbols that start with .X, so we
308 recognize them here. FIXME: do other SVR4 compilers also use .X?.
309 If so, we should move the .X recognition into
310 _bfd_elf_is_local_label_name. */
311
312 static boolean
313 elf_i386_is_local_label_name (abfd, name)
314 bfd *abfd;
315 const char *name;
316 {
317 if (name[0] == '.' && name[1] == 'X')
318 return true;
319
320 return _bfd_elf_is_local_label_name (abfd, name);
321 }
322 \f
323 /* Support for core dump NOTE sections. */
324 static boolean
325 elf_i386_grok_prstatus (abfd, note)
326 bfd *abfd;
327 Elf_Internal_Note *note;
328 {
329 int offset;
330 size_t raw_size;
331
332 switch (note->descsz)
333 {
334 default:
335 return false;
336
337 case 144: /* Linux/i386 */
338 /* pr_cursig */
339 elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12);
340
341 /* pr_pid */
342 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
343
344 /* pr_reg */
345 offset = 72;
346 raw_size = 68;
347
348 break;
349 }
350
351 /* Make a ".reg/999" section. */
352 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
353 raw_size, note->descpos + offset);
354 }
355
356 static boolean
357 elf_i386_grok_psinfo (abfd, note)
358 bfd *abfd;
359 Elf_Internal_Note *note;
360 {
361 switch (note->descsz)
362 {
363 default:
364 return false;
365
366 case 128: /* Linux/MIPS elf_prpsinfo */
367 elf_tdata (abfd)->core_program
368 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
369 elf_tdata (abfd)->core_command
370 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
371 }
372
373 /* Note that for some reason, a spurious space is tacked
374 onto the end of the args in some (at least one anyway)
375 implementations, so strip it off if it exists. */
376
377 {
378 char *command = elf_tdata (abfd)->core_command;
379 int n = strlen (command);
380
381 if (0 < n && command[n - 1] == ' ')
382 command[n - 1] = '\0';
383 }
384
385 return true;
386 }
387 \f
388 /* Functions for the i386 ELF linker.
389
390 In order to gain some understanding of code in this file without
391 knowing all the intricate details of the linker, note the
392 following:
393
394 Functions named elf_i386_* are called by external routines, other
395 functions are only called locally. elf_i386_* functions appear
396 in this file more or less in the order in which they are called
397 from external routines. eg. elf_i386_check_relocs is called
398 early in the link process, elf_i386_finish_dynamic_sections is
399 one of the last functions. */
400
401
402 /* The name of the dynamic interpreter. This is put in the .interp
403 section. */
404
405 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
406
407 /* The size in bytes of an entry in the procedure linkage table. */
408
409 #define PLT_ENTRY_SIZE 16
410
411 /* The first entry in an absolute procedure linkage table looks like
412 this. See the SVR4 ABI i386 supplement to see how this works. */
413
414 static const bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
415 {
416 0xff, 0x35, /* pushl contents of address */
417 0, 0, 0, 0, /* replaced with address of .got + 4. */
418 0xff, 0x25, /* jmp indirect */
419 0, 0, 0, 0, /* replaced with address of .got + 8. */
420 0, 0, 0, 0 /* pad out to 16 bytes. */
421 };
422
423 /* Subsequent entries in an absolute procedure linkage table look like
424 this. */
425
426 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
427 {
428 0xff, 0x25, /* jmp indirect */
429 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
430 0x68, /* pushl immediate */
431 0, 0, 0, 0, /* replaced with offset into relocation table. */
432 0xe9, /* jmp relative */
433 0, 0, 0, 0 /* replaced with offset to start of .plt. */
434 };
435
436 /* The first entry in a PIC procedure linkage table look like this. */
437
438 static const bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
439 {
440 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
441 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
442 0, 0, 0, 0 /* pad out to 16 bytes. */
443 };
444
445 /* Subsequent entries in a PIC procedure linkage table look like this. */
446
447 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
448 {
449 0xff, 0xa3, /* jmp *offset(%ebx) */
450 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
451 0x68, /* pushl immediate */
452 0, 0, 0, 0, /* replaced with offset into relocation table. */
453 0xe9, /* jmp relative */
454 0, 0, 0, 0 /* replaced with offset to start of .plt. */
455 };
456
457 /* The i386 linker needs to keep track of the number of relocs that it
458 decides to copy as dynamic relocs in check_relocs for each symbol.
459 This is so that it can later discard them if they are found to be
460 unnecessary. We store the information in a field extending the
461 regular ELF linker hash table. */
462
463 struct elf_i386_dyn_relocs
464 {
465 struct elf_i386_dyn_relocs *next;
466
467 /* The input section of the reloc. */
468 asection *sec;
469
470 /* Total number of relocs copied for the input section. */
471 bfd_size_type count;
472
473 /* Number of pc-relative relocs copied for the input section. */
474 bfd_size_type pc_count;
475 };
476
477 /* i386 ELF linker hash entry. */
478
479 struct elf_i386_link_hash_entry
480 {
481 struct elf_link_hash_entry elf;
482
483 /* Track dynamic relocs copied for this symbol. */
484 struct elf_i386_dyn_relocs *dyn_relocs;
485 };
486
487 /* i386 ELF linker hash table. */
488
489 struct elf_i386_link_hash_table
490 {
491 struct elf_link_hash_table elf;
492
493 /* Short-cuts to get to dynamic linker sections. */
494 asection *sgot;
495 asection *sgotplt;
496 asection *srelgot;
497 asection *splt;
498 asection *srelplt;
499 asection *sdynbss;
500 asection *srelbss;
501 };
502
503 /* Get the i386 ELF linker hash table from a link_info structure. */
504
505 #define elf_i386_hash_table(p) \
506 ((struct elf_i386_link_hash_table *) ((p)->hash))
507
508 /* Create an entry in an i386 ELF linker hash table. */
509
510 static struct bfd_hash_entry *
511 link_hash_newfunc (entry, table, string)
512 struct bfd_hash_entry *entry;
513 struct bfd_hash_table *table;
514 const char *string;
515 {
516 /* Allocate the structure if it has not already been allocated by a
517 subclass. */
518 if (entry == NULL)
519 {
520 entry = bfd_hash_allocate (table,
521 sizeof (struct elf_i386_link_hash_entry));
522 if (entry == NULL)
523 return entry;
524 }
525
526 /* Call the allocation method of the superclass. */
527 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
528 if (entry != NULL)
529 {
530 struct elf_i386_link_hash_entry *eh;
531
532 eh = (struct elf_i386_link_hash_entry *) entry;
533 eh->dyn_relocs = NULL;
534 }
535
536 return entry;
537 }
538
539 /* Create an i386 ELF linker hash table. */
540
541 static struct bfd_link_hash_table *
542 elf_i386_link_hash_table_create (abfd)
543 bfd *abfd;
544 {
545 struct elf_i386_link_hash_table *ret;
546 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table);
547
548 ret = (struct elf_i386_link_hash_table *) bfd_alloc (abfd, amt);
549 if (ret == NULL)
550 return NULL;
551
552 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
553 {
554 bfd_release (abfd, ret);
555 return NULL;
556 }
557
558 ret->sgot = NULL;
559 ret->sgotplt = NULL;
560 ret->srelgot = NULL;
561 ret->splt = NULL;
562 ret->srelplt = NULL;
563 ret->sdynbss = NULL;
564 ret->srelbss = NULL;
565
566 return &ret->elf.root;
567 }
568
569 /* Create .got, .gotplt, and .rel.got sections in DYNOBJ, and set up
570 shortcuts to them in our hash table. */
571
572 static boolean
573 create_got_section (dynobj, info)
574 bfd *dynobj;
575 struct bfd_link_info *info;
576 {
577 struct elf_i386_link_hash_table *htab;
578
579 if (! _bfd_elf_create_got_section (dynobj, info))
580 return false;
581
582 htab = elf_i386_hash_table (info);
583 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
584 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
585 if (!htab->sgot || !htab->sgotplt)
586 abort ();
587
588 htab->srelgot = bfd_make_section (dynobj, ".rel.got");
589 if (htab->srelgot == NULL
590 || ! bfd_set_section_flags (dynobj, htab->srelgot,
591 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
592 | SEC_IN_MEMORY | SEC_LINKER_CREATED
593 | SEC_READONLY))
594 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2))
595 return false;
596 return true;
597 }
598
599 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and
600 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our
601 hash table. */
602
603 static boolean
604 elf_i386_create_dynamic_sections (dynobj, info)
605 bfd *dynobj;
606 struct bfd_link_info *info;
607 {
608 struct elf_i386_link_hash_table *htab;
609
610 htab = elf_i386_hash_table (info);
611 if (!htab->sgot && !create_got_section (dynobj, info))
612 return false;
613
614 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
615 return false;
616
617 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
618 htab->srelplt = bfd_get_section_by_name (dynobj, ".rel.plt");
619 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
620 if (!info->shared)
621 htab->srelbss = bfd_get_section_by_name (dynobj, ".rel.bss");
622
623 if (!htab->splt || !htab->srelplt || !htab->sdynbss
624 || (!info->shared && !htab->srelbss))
625 abort ();
626
627 return true;
628 }
629
630 /* Copy the extra info we tack onto an elf_link_hash_entry. */
631
632 void
633 elf_i386_copy_indirect_symbol (dir, ind)
634 struct elf_link_hash_entry *dir, *ind;
635 {
636 struct elf_i386_link_hash_entry *edir, *eind;
637
638 edir = (struct elf_i386_link_hash_entry *) dir;
639 eind = (struct elf_i386_link_hash_entry *) ind;
640
641 if (edir->dyn_relocs == NULL)
642 {
643 edir->dyn_relocs = eind->dyn_relocs;
644 eind->dyn_relocs = NULL;
645 }
646 else if (eind->dyn_relocs != NULL)
647 abort ();
648
649 _bfd_elf_link_hash_copy_indirect (dir, ind);
650 }
651
652 /* Look through the relocs for a section during the first phase, and
653 allocate space in the global offset table or procedure linkage
654 table. */
655
656 static boolean
657 elf_i386_check_relocs (abfd, info, sec, relocs)
658 bfd *abfd;
659 struct bfd_link_info *info;
660 asection *sec;
661 const Elf_Internal_Rela *relocs;
662 {
663 struct elf_i386_link_hash_table *htab;
664 bfd *dynobj;
665 Elf_Internal_Shdr *symtab_hdr;
666 struct elf_link_hash_entry **sym_hashes;
667 bfd_signed_vma *local_got_refcounts;
668 const Elf_Internal_Rela *rel;
669 const Elf_Internal_Rela *rel_end;
670 asection *sreloc;
671
672 if (info->relocateable)
673 return true;
674
675 htab = elf_i386_hash_table (info);
676 dynobj = htab->elf.dynobj;
677 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
678 sym_hashes = elf_sym_hashes (abfd);
679 local_got_refcounts = elf_local_got_refcounts (abfd);
680
681 sreloc = NULL;
682
683 rel_end = relocs + sec->reloc_count;
684 for (rel = relocs; rel < rel_end; rel++)
685 {
686 unsigned long r_symndx;
687 struct elf_link_hash_entry *h;
688
689 r_symndx = ELF32_R_SYM (rel->r_info);
690
691 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
692 {
693 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
694 bfd_archive_filename (abfd),
695 r_symndx);
696 return false;
697 }
698
699 if (r_symndx < symtab_hdr->sh_info)
700 h = NULL;
701 else
702 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
703
704 /* Some relocs require a global offset table. */
705 if (htab->sgot == NULL)
706 {
707 switch (ELF32_R_TYPE (rel->r_info))
708 {
709 case R_386_GOT32:
710 case R_386_GOTOFF:
711 case R_386_GOTPC:
712 if (dynobj == NULL)
713 htab->elf.dynobj = dynobj = abfd;
714 if (!create_got_section (dynobj, info))
715 return false;
716 break;
717
718 default:
719 break;
720 }
721 }
722
723 switch (ELF32_R_TYPE (rel->r_info))
724 {
725 case R_386_GOT32:
726 /* This symbol requires a global offset table entry. */
727 if (h != NULL)
728 {
729 if (h->got.refcount == -1)
730 h->got.refcount = 1;
731 else
732 h->got.refcount += 1;
733 }
734 else
735 {
736 /* This is a global offset table entry for a local symbol. */
737 if (local_got_refcounts == NULL)
738 {
739 bfd_size_type size;
740
741 size = symtab_hdr->sh_info;
742 size *= sizeof (bfd_signed_vma);
743 local_got_refcounts = ((bfd_signed_vma *)
744 bfd_zalloc (abfd, size));
745 if (local_got_refcounts == NULL)
746 return false;
747 elf_local_got_refcounts (abfd) = local_got_refcounts;
748 }
749 local_got_refcounts[r_symndx] += 1;
750 }
751 break;
752
753 case R_386_PLT32:
754 /* This symbol requires a procedure linkage table entry. We
755 actually build the entry in adjust_dynamic_symbol,
756 because this might be a case of linking PIC code which is
757 never referenced by a dynamic object, in which case we
758 don't need to generate a procedure linkage table entry
759 after all. */
760
761 /* If this is a local symbol, we resolve it directly without
762 creating a procedure linkage table entry. */
763 if (h == NULL)
764 continue;
765
766 if (h->plt.refcount == -1)
767 {
768 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
769 h->plt.refcount = 1;
770 }
771 else
772 h->plt.refcount += 1;
773 break;
774
775 case R_386_32:
776 case R_386_PC32:
777 if (h != NULL && !info->shared)
778 {
779 /* If this reloc is in a read-only section, we might
780 need a copy reloc. We can't check reliably at this
781 stage whether the section is read-only, as input
782 sections have not yet been mapped to output sections.
783 Tentatively set the flag for now, and correct in
784 adjust_dynamic_symbol. */
785 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
786
787 /* We may need a .plt entry if the function this reloc
788 refers to is in a shared lib. */
789 if (h->plt.refcount == -1)
790 h->plt.refcount = 1;
791 else
792 h->plt.refcount += 1;
793 }
794
795 /* If we are creating a shared library, and this is a reloc
796 against a global symbol, or a non PC relative reloc
797 against a local symbol, then we need to copy the reloc
798 into the shared library. However, if we are linking with
799 -Bsymbolic, we do not need to copy a reloc against a
800 global symbol which is defined in an object we are
801 including in the link (i.e., DEF_REGULAR is set). At
802 this point we have not seen all the input files, so it is
803 possible that DEF_REGULAR is not set now but will be set
804 later (it is never cleared). In case of a weak definition,
805 DEF_REGULAR may be cleared later by a strong definition in
806 a shared library. We account for that possibility below by
807 storing information in the relocs_copied field of the hash
808 table entry. A similar situation occurs when creating
809 shared libraries and symbol visibility changes render the
810 symbol local.
811
812 If on the other hand, we are creating an executable, we
813 may need to keep relocations for symbols satisfied by a
814 dynamic library if we manage to avoid copy relocs for the
815 symbol. */
816 if ((info->shared
817 && (sec->flags & SEC_ALLOC) != 0
818 && (ELF32_R_TYPE (rel->r_info) != R_386_PC32
819 || (h != NULL
820 && (! info->symbolic
821 || h->root.type == bfd_link_hash_defweak
822 || (h->elf_link_hash_flags
823 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
824 || (!info->shared
825 && (sec->flags & SEC_ALLOC) != 0
826 && h != NULL
827 && (h->root.type == bfd_link_hash_defweak
828 || (h->elf_link_hash_flags
829 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
830 {
831 /* We must copy these reloc types into the output file.
832 Create a reloc section in dynobj and make room for
833 this reloc. */
834 if (dynobj == NULL)
835 htab->elf.dynobj = dynobj = abfd;
836
837 if (sreloc == NULL)
838 {
839 const char *name;
840
841 name = (bfd_elf_string_from_elf_section
842 (abfd,
843 elf_elfheader (abfd)->e_shstrndx,
844 elf_section_data (sec)->rel_hdr.sh_name));
845 if (name == NULL)
846 return false;
847
848 if (strncmp (name, ".rel", 4) != 0
849 || strcmp (bfd_get_section_name (abfd, sec),
850 name + 4) != 0)
851 {
852 (*_bfd_error_handler)
853 (_("%s: bad relocation section name `%s\'"),
854 bfd_archive_filename (abfd), name);
855 }
856
857 sreloc = bfd_get_section_by_name (dynobj, name);
858 if (sreloc == NULL)
859 {
860 flagword flags;
861
862 sreloc = bfd_make_section (dynobj, name);
863 flags = (SEC_HAS_CONTENTS | SEC_READONLY
864 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
865 if ((sec->flags & SEC_ALLOC) != 0)
866 flags |= SEC_ALLOC | SEC_LOAD;
867 if (sreloc == NULL
868 || ! bfd_set_section_flags (dynobj, sreloc, flags)
869 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
870 return false;
871 }
872 elf_section_data (sec)->sreloc = sreloc;
873 }
874
875 /* If this is a global symbol, we count the number of
876 relocations we need for this symbol. */
877 if (h != NULL)
878 {
879 struct elf_i386_link_hash_entry *eh;
880 struct elf_i386_dyn_relocs *p;
881
882 eh = (struct elf_i386_link_hash_entry *) h;
883 p = eh->dyn_relocs;
884
885 if (p == NULL || p->sec != sec)
886 {
887 p = ((struct elf_i386_dyn_relocs *)
888 bfd_alloc (dynobj, (bfd_size_type) sizeof *p));
889 if (p == NULL)
890 return false;
891 p->next = eh->dyn_relocs;
892 eh->dyn_relocs = p;
893 p->sec = sec;
894 p->count = 0;
895 p->pc_count = 0;
896 }
897
898 p->count += 1;
899 if (ELF32_R_TYPE (rel->r_info) == R_386_PC32)
900 p->pc_count += 1;
901 }
902 else
903 {
904 /* Track dynamic relocs needed for local syms too. */
905 elf_section_data (sec)->local_dynrel += 1;
906 }
907 }
908
909 break;
910
911 /* This relocation describes the C++ object vtable hierarchy.
912 Reconstruct it for later use during GC. */
913 case R_386_GNU_VTINHERIT:
914 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
915 return false;
916 break;
917
918 /* This relocation describes which C++ vtable entries are actually
919 used. Record for later use during GC. */
920 case R_386_GNU_VTENTRY:
921 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
922 return false;
923 break;
924
925 default:
926 break;
927 }
928 }
929
930 return true;
931 }
932
933 /* Return the section that should be marked against GC for a given
934 relocation. */
935
936 static asection *
937 elf_i386_gc_mark_hook (abfd, info, rel, h, sym)
938 bfd *abfd;
939 struct bfd_link_info *info ATTRIBUTE_UNUSED;
940 Elf_Internal_Rela *rel;
941 struct elf_link_hash_entry *h;
942 Elf_Internal_Sym *sym;
943 {
944 if (h != NULL)
945 {
946 switch (ELF32_R_TYPE (rel->r_info))
947 {
948 case R_386_GNU_VTINHERIT:
949 case R_386_GNU_VTENTRY:
950 break;
951
952 default:
953 switch (h->root.type)
954 {
955 case bfd_link_hash_defined:
956 case bfd_link_hash_defweak:
957 return h->root.u.def.section;
958
959 case bfd_link_hash_common:
960 return h->root.u.c.p->section;
961
962 default:
963 break;
964 }
965 }
966 }
967 else
968 {
969 if (!(elf_bad_symtab (abfd)
970 && ELF_ST_BIND (sym->st_info) != STB_LOCAL)
971 && ! ((sym->st_shndx <= 0 || sym->st_shndx >= SHN_LORESERVE)
972 && sym->st_shndx != SHN_COMMON))
973 {
974 return bfd_section_from_elf_index (abfd, sym->st_shndx);
975 }
976 }
977
978 return NULL;
979 }
980
981 /* Update the got entry reference counts for the section being removed. */
982
983 static boolean
984 elf_i386_gc_sweep_hook (abfd, info, sec, relocs)
985 bfd *abfd;
986 struct bfd_link_info *info;
987 asection *sec;
988 const Elf_Internal_Rela *relocs;
989 {
990 Elf_Internal_Shdr *symtab_hdr;
991 struct elf_link_hash_entry **sym_hashes;
992 bfd_signed_vma *local_got_refcounts;
993 const Elf_Internal_Rela *rel, *relend;
994 unsigned long r_symndx;
995 struct elf_link_hash_entry *h;
996 bfd *dynobj;
997
998 elf_section_data (sec)->local_dynrel = 0;
999
1000 dynobj = elf_hash_table (info)->dynobj;
1001 if (dynobj == NULL)
1002 return true;
1003
1004 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1005 sym_hashes = elf_sym_hashes (abfd);
1006 local_got_refcounts = elf_local_got_refcounts (abfd);
1007
1008 relend = relocs + sec->reloc_count;
1009 for (rel = relocs; rel < relend; rel++)
1010 switch (ELF32_R_TYPE (rel->r_info))
1011 {
1012 case R_386_GOT32:
1013 case R_386_GOTOFF:
1014 case R_386_GOTPC:
1015 r_symndx = ELF32_R_SYM (rel->r_info);
1016 if (r_symndx >= symtab_hdr->sh_info)
1017 {
1018 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1019 if (h->got.refcount > 0)
1020 h->got.refcount -= 1;
1021 }
1022 else if (local_got_refcounts != NULL)
1023 {
1024 if (local_got_refcounts[r_symndx] > 0)
1025 local_got_refcounts[r_symndx] -= 1;
1026 }
1027 break;
1028
1029 case R_386_32:
1030 case R_386_PC32:
1031 r_symndx = ELF32_R_SYM (rel->r_info);
1032 if (r_symndx >= symtab_hdr->sh_info)
1033 {
1034 struct elf_i386_link_hash_entry *eh;
1035 struct elf_i386_dyn_relocs **pp;
1036 struct elf_i386_dyn_relocs *p;
1037
1038 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1039
1040 if (!info->shared && h->plt.refcount > 0)
1041 h->plt.refcount -= 1;
1042
1043 eh = (struct elf_i386_link_hash_entry *) h;
1044
1045 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1046 if (p->sec == sec)
1047 {
1048 if (ELF32_R_TYPE (rel->r_info) == R_386_PC32)
1049 p->pc_count -= 1;
1050 p->count -= 1;
1051 if (p->count == 0)
1052 *pp = p->next;
1053 break;
1054 }
1055 }
1056 break;
1057
1058 case R_386_PLT32:
1059 r_symndx = ELF32_R_SYM (rel->r_info);
1060 if (r_symndx >= symtab_hdr->sh_info)
1061 {
1062 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1063 if (h->plt.refcount > 0)
1064 h->plt.refcount -= 1;
1065 }
1066 break;
1067
1068 default:
1069 break;
1070 }
1071
1072 return true;
1073 }
1074
1075 /* Adjust a symbol defined by a dynamic object and referenced by a
1076 regular object. The current definition is in some section of the
1077 dynamic object, but we're not including those sections. We have to
1078 change the definition to something the rest of the link can
1079 understand. */
1080
1081 static boolean
1082 elf_i386_adjust_dynamic_symbol (info, h)
1083 struct bfd_link_info *info;
1084 struct elf_link_hash_entry *h;
1085 {
1086 struct elf_i386_link_hash_table *htab;
1087 bfd *dynobj;
1088 struct elf_i386_link_hash_entry * eh;
1089 struct elf_i386_dyn_relocs *p;
1090 asection *s;
1091 unsigned int power_of_two;
1092
1093 htab = elf_i386_hash_table (info);
1094 dynobj = htab->elf.dynobj;
1095
1096 /* If this is a function, put it in the procedure linkage table. We
1097 will fill in the contents of the procedure linkage table later,
1098 when we know the address of the .got section. */
1099 if (h->type == STT_FUNC
1100 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1101 {
1102 if (h->plt.refcount <= 0
1103 || (! info->shared
1104 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1105 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0))
1106 {
1107 /* This case can occur if we saw a PLT32 reloc in an input
1108 file, but the symbol was never referred to by a dynamic
1109 object, or if all references were garbage collected. In
1110 such a case, we don't actually need to build a procedure
1111 linkage table, and we can just do a PC32 reloc instead. */
1112 h->plt.refcount = (bfd_vma) -1;
1113 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1114 }
1115
1116 return true;
1117 }
1118 else
1119 /* It's possible that we incorrectly decided a .plt reloc was
1120 needed for an R_386_PC32 reloc to a non-function sym in
1121 check_relocs. We can't decide accurately between function and
1122 non-function syms in check-relocs; Objects loaded later in
1123 the link may change h->type. So fix it now. */
1124 h->plt.refcount = (bfd_vma) -1;
1125
1126 /* If this is a weak symbol, and there is a real definition, the
1127 processor independent code will have arranged for us to see the
1128 real definition first, and we can just use the same value. */
1129 if (h->weakdef != NULL)
1130 {
1131 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1132 || h->weakdef->root.type == bfd_link_hash_defweak);
1133 h->root.u.def.section = h->weakdef->root.u.def.section;
1134 h->root.u.def.value = h->weakdef->root.u.def.value;
1135 }
1136
1137 /* This is a reference to a symbol defined by a dynamic object which
1138 is not a function. */
1139
1140 /* If we are creating a shared library, we must presume that the
1141 only references to the symbol are via the global offset table.
1142 For such cases we need not do anything here; the relocations will
1143 be handled correctly by relocate_section. */
1144 if (info->shared)
1145 return true;
1146
1147 /* If there are no references to this symbol that do not use the
1148 GOT, we don't need to generate a copy reloc. */
1149 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1150 return true;
1151
1152 eh = (struct elf_i386_link_hash_entry *) h;
1153 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1154 {
1155 s = p->sec->output_section;
1156 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1157 break;
1158 }
1159
1160 /* If we didn't find any dynamic relocs in read-only sections, then
1161 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1162 if (p == NULL)
1163 {
1164 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1165 return true;
1166 }
1167
1168 /* We must allocate the symbol in our .dynbss section, which will
1169 become part of the .bss section of the executable. There will be
1170 an entry for this symbol in the .dynsym section. The dynamic
1171 object will contain position independent code, so all references
1172 from the dynamic object to this symbol will go through the global
1173 offset table. The dynamic linker will use the .dynsym entry to
1174 determine the address it must put in the global offset table, so
1175 both the dynamic object and the regular object will refer to the
1176 same memory location for the variable. */
1177
1178 s = htab->sdynbss;
1179 if (s == NULL)
1180 abort ();
1181
1182 /* We must generate a R_386_COPY reloc to tell the dynamic linker to
1183 copy the initial value out of the dynamic object and into the
1184 runtime process image. We need to remember the offset into the
1185 .rel.bss section we are going to use. */
1186 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1187 {
1188 asection *srel;
1189
1190 srel = htab->srelbss;
1191 if (srel == NULL)
1192 abort ();
1193 srel->_raw_size += sizeof (Elf32_External_Rel);
1194 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1195 }
1196
1197 /* We need to figure out the alignment required for this symbol. I
1198 have no idea how ELF linkers handle this. */
1199 power_of_two = bfd_log2 (h->size);
1200 if (power_of_two > 3)
1201 power_of_two = 3;
1202
1203 /* Apply the required alignment. */
1204 s->_raw_size = BFD_ALIGN (s->_raw_size,
1205 (bfd_size_type) (1 << power_of_two));
1206 if (power_of_two > bfd_get_section_alignment (dynobj, s))
1207 {
1208 if (! bfd_set_section_alignment (dynobj, s, power_of_two))
1209 return false;
1210 }
1211
1212 /* Define the symbol as being at this point in the section. */
1213 h->root.u.def.section = s;
1214 h->root.u.def.value = s->_raw_size;
1215
1216 /* Increment the section size to make room for the symbol. */
1217 s->_raw_size += h->size;
1218
1219 return true;
1220 }
1221
1222 /* This is the condition under which elf_i386_finish_dynamic_symbol
1223 will be called from elflink.h. If elflink.h doesn't call our
1224 finish_dynamic_symbol routine, we'll need to do something about
1225 initializing any .plt and .got entries in elf_i386_relocate_section. */
1226 #define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, INFO, H) \
1227 ((DYN) \
1228 && ((INFO)->shared \
1229 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \
1230 && ((H)->dynindx != -1 \
1231 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0))
1232
1233 /* Allocate space in .plt, .got and associated reloc sections for
1234 dynamic relocs. */
1235
1236 static boolean
1237 allocate_dynrelocs (h, inf)
1238 struct elf_link_hash_entry *h;
1239 PTR inf;
1240 {
1241 struct bfd_link_info *info;
1242 struct elf_i386_link_hash_table *htab;
1243 asection *s;
1244 struct elf_i386_link_hash_entry *eh;
1245 struct elf_i386_dyn_relocs *p;
1246
1247 if (h->root.type == bfd_link_hash_indirect
1248 || h->root.type == bfd_link_hash_warning)
1249 return true;
1250
1251 info = (struct bfd_link_info *) inf;
1252 htab = elf_i386_hash_table (info);
1253
1254 if (htab->elf.dynamic_sections_created
1255 && h->plt.refcount > 0)
1256 {
1257 /* Make sure this symbol is output as a dynamic symbol.
1258 Undefined weak syms won't yet be marked as dynamic. */
1259 if (h->dynindx == -1
1260 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1261 {
1262 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1263 return false;
1264 }
1265
1266 s = htab->splt;
1267 if (s == NULL)
1268 abort ();
1269
1270 /* If this is the first .plt entry, make room for the special
1271 first entry. */
1272 if (s->_raw_size == 0)
1273 s->_raw_size += PLT_ENTRY_SIZE;
1274
1275 h->plt.offset = s->_raw_size;
1276
1277 /* If this symbol is not defined in a regular file, and we are
1278 not generating a shared library, then set the symbol to this
1279 location in the .plt. This is required to make function
1280 pointers compare as equal between the normal executable and
1281 the shared library. */
1282 if (! info->shared
1283 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1284 {
1285 h->root.u.def.section = s;
1286 h->root.u.def.value = h->plt.offset;
1287 }
1288
1289 /* Make room for this entry. */
1290 s->_raw_size += PLT_ENTRY_SIZE;
1291
1292 /* We also need to make an entry in the .got.plt section, which
1293 will be placed in the .got section by the linker script. */
1294 s = htab->sgotplt;
1295 if (s == NULL)
1296 abort ();
1297 s->_raw_size += 4;
1298
1299 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h))
1300 {
1301 /* We also need to make an entry in the .rel.plt section. */
1302 s = htab->srelplt;
1303 if (s == NULL)
1304 abort ();
1305 s->_raw_size += sizeof (Elf32_External_Rel);
1306 }
1307 }
1308 else
1309 {
1310 h->plt.offset = (bfd_vma) -1;
1311 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1312 }
1313
1314 if (h->got.refcount > 0)
1315 {
1316 boolean dyn;
1317
1318 /* Make sure this symbol is output as a dynamic symbol.
1319 Undefined weak syms won't yet be marked as dynamic. */
1320 if (h->dynindx == -1
1321 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1322 {
1323 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1324 return false;
1325 }
1326
1327 s = htab->sgot;
1328 h->got.offset = s->_raw_size;
1329 s->_raw_size += 4;
1330 dyn = htab->elf.dynamic_sections_created;
1331 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
1332 htab->srelgot->_raw_size += sizeof (Elf32_External_Rel);
1333 }
1334 else
1335 h->got.offset = (bfd_vma) -1;
1336
1337 eh = (struct elf_i386_link_hash_entry *) h;
1338 if (eh->dyn_relocs == NULL)
1339 return true;
1340
1341 /* In the shared -Bsymbolic case, discard space allocated for
1342 dynamic pc-relative relocs against symbols which turn out to be
1343 defined in regular objects. For the normal shared case, discard
1344 space for relocs that have become local due to symbol visibility
1345 changes. */
1346
1347 if (info->shared)
1348 {
1349 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1350 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1351 || info->symbolic))
1352 {
1353 struct elf_i386_dyn_relocs **pp;
1354
1355 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1356 {
1357 p->count -= p->pc_count;
1358 p->pc_count = 0;
1359 if (p->count == 0)
1360 *pp = p->next;
1361 else
1362 pp = &p->next;
1363 }
1364 }
1365 }
1366 else
1367 {
1368 /* For the non-shared case, discard space for relocs against
1369 symbols which turn out to need copy relocs or are not
1370 dynamic. */
1371
1372 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1373 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1374 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1375 || (htab->elf.dynamic_sections_created
1376 && (h->root.type == bfd_link_hash_undefweak
1377 || h->root.type == bfd_link_hash_undefined))))
1378 {
1379 /* Make sure this symbol is output as a dynamic symbol.
1380 Undefined weak syms won't yet be marked as dynamic. */
1381 if (h->dynindx == -1
1382 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1383 {
1384 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1385 return false;
1386 }
1387
1388 /* If that succeeded, we know we'll be keeping all the
1389 relocs. */
1390 if (h->dynindx != -1)
1391 goto keep;
1392 }
1393
1394 eh->dyn_relocs = NULL;
1395
1396 keep:
1397 }
1398
1399 /* Finally, allocate space. */
1400 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1401 {
1402 asection *sreloc = elf_section_data (p->sec)->sreloc;
1403 sreloc->_raw_size += p->count * sizeof (Elf32_External_Rel);
1404 }
1405
1406 return true;
1407 }
1408
1409 /* Find any dynamic relocs that apply to read-only sections. */
1410
1411 static boolean
1412 readonly_dynrelocs (h, inf)
1413 struct elf_link_hash_entry *h;
1414 PTR inf;
1415 {
1416 struct elf_i386_link_hash_entry *eh;
1417 struct elf_i386_dyn_relocs *p;
1418
1419 eh = (struct elf_i386_link_hash_entry *) h;
1420 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1421 {
1422 asection *s = p->sec->output_section;
1423
1424 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1425 {
1426 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1427
1428 info->flags |= DF_TEXTREL;
1429
1430 /* Not an error, just cut short the traversal. */
1431 return false;
1432 }
1433 }
1434 return true;
1435 }
1436
1437 /* Set the sizes of the dynamic sections. */
1438
1439 static boolean
1440 elf_i386_size_dynamic_sections (output_bfd, info)
1441 bfd *output_bfd ATTRIBUTE_UNUSED;
1442 struct bfd_link_info *info;
1443 {
1444 struct elf_i386_link_hash_table *htab;
1445 bfd *dynobj;
1446 asection *s;
1447 boolean relocs;
1448 bfd *ibfd;
1449
1450 htab = elf_i386_hash_table (info);
1451 dynobj = htab->elf.dynobj;
1452 if (dynobj == NULL)
1453 abort ();
1454
1455 if (htab->elf.dynamic_sections_created)
1456 {
1457 /* Set the contents of the .interp section to the interpreter. */
1458 if (! info->shared)
1459 {
1460 s = bfd_get_section_by_name (dynobj, ".interp");
1461 if (s == NULL)
1462 abort ();
1463 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1464 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1465 }
1466 }
1467
1468 /* Set up .got offsets for local syms, and space for local dynamic
1469 relocs. */
1470 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1471 {
1472 bfd_signed_vma *local_got;
1473 bfd_signed_vma *end_local_got;
1474 bfd_size_type locsymcount;
1475 Elf_Internal_Shdr *symtab_hdr;
1476 asection *srel;
1477
1478 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1479 continue;
1480
1481 for (s = ibfd->sections; s != NULL; s = s->next)
1482 {
1483 bfd_size_type count = elf_section_data (s)->local_dynrel;
1484
1485 if (count != 0)
1486 {
1487 srel = elf_section_data (s)->sreloc;
1488 srel->_raw_size += count * sizeof (Elf32_External_Rel);
1489 }
1490 }
1491
1492 local_got = elf_local_got_refcounts (ibfd);
1493 if (!local_got)
1494 continue;
1495
1496 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1497 locsymcount = symtab_hdr->sh_info;
1498 end_local_got = local_got + locsymcount;
1499 s = htab->sgot;
1500 srel = htab->srelgot;
1501 for (; local_got < end_local_got; ++local_got)
1502 {
1503 if (*local_got > 0)
1504 {
1505 *local_got = s->_raw_size;
1506 s->_raw_size += 4;
1507 if (info->shared)
1508 srel->_raw_size += sizeof (Elf32_External_Rel);
1509 }
1510 else
1511 *local_got = (bfd_vma) -1;
1512 }
1513 }
1514
1515 /* Allocate global sym .plt and .got entries, and space for global
1516 sym dynamic relocs. */
1517 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1518
1519 /* We now have determined the sizes of the various dynamic sections.
1520 Allocate memory for them. */
1521 relocs = false;
1522 for (s = dynobj->sections; s != NULL; s = s->next)
1523 {
1524 if ((s->flags & SEC_LINKER_CREATED) == 0)
1525 continue;
1526
1527 if (s == htab->splt
1528 || s == htab->sgot
1529 || s == htab->sgotplt)
1530 {
1531 /* Strip this section if we don't need it; see the
1532 comment below. */
1533 }
1534 else if (strncmp (bfd_get_section_name (dynobj, s), ".rel", 4) == 0)
1535 {
1536 if (s->_raw_size == 0)
1537 {
1538 /* If we don't need this section, strip it from the
1539 output file. This is mostly to handle .rel.bss and
1540 .rel.plt. We must create both sections in
1541 create_dynamic_sections, because they must be created
1542 before the linker maps input sections to output
1543 sections. The linker does that before
1544 adjust_dynamic_symbol is called, and it is that
1545 function which decides whether anything needs to go
1546 into these sections. */
1547 }
1548 else
1549 {
1550 if (s != htab->srelplt)
1551 relocs = true;
1552
1553 /* We use the reloc_count field as a counter if we need
1554 to copy relocs into the output file. */
1555 s->reloc_count = 0;
1556 }
1557 }
1558 else
1559 {
1560 /* It's not one of our sections, so don't allocate space. */
1561 continue;
1562 }
1563
1564 if (s->_raw_size == 0)
1565 {
1566 _bfd_strip_section_from_output (info, s);
1567 continue;
1568 }
1569
1570 /* Allocate memory for the section contents. We use bfd_zalloc
1571 here in case unused entries are not reclaimed before the
1572 section's contents are written out. This should not happen,
1573 but this way if it does, we get a R_386_NONE reloc instead
1574 of garbage. */
1575 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1576 if (s->contents == NULL)
1577 return false;
1578 }
1579
1580 if (htab->elf.dynamic_sections_created)
1581 {
1582 /* Add some entries to the .dynamic section. We fill in the
1583 values later, in elf_i386_finish_dynamic_sections, but we
1584 must add the entries now so that we get the correct size for
1585 the .dynamic section. The DT_DEBUG entry is filled in by the
1586 dynamic linker and used by the debugger. */
1587 #define add_dynamic_entry(TAG, VAL) \
1588 bfd_elf32_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1589
1590 if (! info->shared)
1591 {
1592 if (!add_dynamic_entry (DT_DEBUG, 0))
1593 return false;
1594 }
1595
1596 if (htab->splt->_raw_size != 0)
1597 {
1598 if (!add_dynamic_entry (DT_PLTGOT, 0)
1599 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1600 || !add_dynamic_entry (DT_PLTREL, DT_REL)
1601 || !add_dynamic_entry (DT_JMPREL, 0))
1602 return false;
1603 }
1604
1605 if (relocs)
1606 {
1607 if (!add_dynamic_entry (DT_REL, 0)
1608 || !add_dynamic_entry (DT_RELSZ, 0)
1609 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel)))
1610 return false;
1611
1612 /* If any dynamic relocs apply to a read-only section,
1613 then we need a DT_TEXTREL entry. */
1614 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs, (PTR) info);
1615
1616 if ((info->flags & DF_TEXTREL) != 0)
1617 {
1618 if (!add_dynamic_entry (DT_TEXTREL, 0))
1619 return false;
1620 }
1621 }
1622 }
1623 #undef add_dynamic_entry
1624
1625 return true;
1626 }
1627
1628 /* Set the correct type for an x86 ELF section. We do this by the
1629 section name, which is a hack, but ought to work. */
1630
1631 static boolean
1632 elf_i386_fake_sections (abfd, hdr, sec)
1633 bfd *abfd ATTRIBUTE_UNUSED;
1634 Elf32_Internal_Shdr *hdr;
1635 asection *sec;
1636 {
1637 register const char *name;
1638
1639 name = bfd_get_section_name (abfd, sec);
1640
1641 /* This is an ugly, but unfortunately necessary hack that is
1642 needed when producing EFI binaries on x86. It tells
1643 elf.c:elf_fake_sections() not to consider ".reloc" as a section
1644 containing ELF relocation info. We need this hack in order to
1645 be able to generate ELF binaries that can be translated into
1646 EFI applications (which are essentially COFF objects). Those
1647 files contain a COFF ".reloc" section inside an ELFNN object,
1648 which would normally cause BFD to segfault because it would
1649 attempt to interpret this section as containing relocation
1650 entries for section "oc". With this hack enabled, ".reloc"
1651 will be treated as a normal data section, which will avoid the
1652 segfault. However, you won't be able to create an ELFNN binary
1653 with a section named "oc" that needs relocations, but that's
1654 the kind of ugly side-effects you get when detecting section
1655 types based on their names... In practice, this limitation is
1656 unlikely to bite. */
1657 if (strcmp (name, ".reloc") == 0)
1658 hdr->sh_type = SHT_PROGBITS;
1659
1660 return true;
1661 }
1662
1663 /* Relocate an i386 ELF section. */
1664
1665 static boolean
1666 elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
1667 contents, relocs, local_syms, local_sections)
1668 bfd *output_bfd;
1669 struct bfd_link_info *info;
1670 bfd *input_bfd;
1671 asection *input_section;
1672 bfd_byte *contents;
1673 Elf_Internal_Rela *relocs;
1674 Elf_Internal_Sym *local_syms;
1675 asection **local_sections;
1676 {
1677 struct elf_i386_link_hash_table *htab;
1678 bfd *dynobj;
1679 Elf_Internal_Shdr *symtab_hdr;
1680 struct elf_link_hash_entry **sym_hashes;
1681 bfd_vma *local_got_offsets;
1682 Elf_Internal_Rela *rel;
1683 Elf_Internal_Rela *relend;
1684
1685 htab = elf_i386_hash_table (info);
1686 dynobj = htab->elf.dynobj;
1687 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1688 sym_hashes = elf_sym_hashes (input_bfd);
1689 local_got_offsets = elf_local_got_offsets (input_bfd);
1690
1691 rel = relocs;
1692 relend = relocs + input_section->reloc_count;
1693 for (; rel < relend; rel++)
1694 {
1695 int r_type;
1696 reloc_howto_type *howto;
1697 unsigned long r_symndx;
1698 struct elf_link_hash_entry *h;
1699 Elf_Internal_Sym *sym;
1700 asection *sec;
1701 bfd_vma off;
1702 bfd_vma relocation;
1703 boolean unresolved_reloc;
1704 bfd_reloc_status_type r;
1705 unsigned int indx;
1706
1707 r_type = ELF32_R_TYPE (rel->r_info);
1708 if (r_type == (int) R_386_GNU_VTINHERIT
1709 || r_type == (int) R_386_GNU_VTENTRY)
1710 continue;
1711
1712 if ((indx = (unsigned) r_type) >= R_386_standard
1713 && ((indx = (unsigned) r_type - R_386_ext_offset) - R_386_standard
1714 >= R_386_ext - R_386_standard))
1715 {
1716 bfd_set_error (bfd_error_bad_value);
1717 return false;
1718 }
1719 howto = elf_howto_table + indx;
1720
1721 r_symndx = ELF32_R_SYM (rel->r_info);
1722
1723 if (info->relocateable)
1724 {
1725 /* This is a relocateable link. We don't have to change
1726 anything, unless the reloc is against a section symbol,
1727 in which case we have to adjust according to where the
1728 section symbol winds up in the output section. */
1729 if (r_symndx < symtab_hdr->sh_info)
1730 {
1731 sym = local_syms + r_symndx;
1732 if (ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1733 {
1734 bfd_vma val;
1735
1736 sec = local_sections[r_symndx];
1737 val = bfd_get_32 (input_bfd, contents + rel->r_offset);
1738 val += sec->output_offset + sym->st_value;
1739 bfd_put_32 (input_bfd, val, contents + rel->r_offset);
1740 }
1741 }
1742
1743 continue;
1744 }
1745
1746 /* This is a final link. */
1747 h = NULL;
1748 sym = NULL;
1749 sec = NULL;
1750 unresolved_reloc = false;
1751 if (r_symndx < symtab_hdr->sh_info)
1752 {
1753 sym = local_syms + r_symndx;
1754 sec = local_sections[r_symndx];
1755 relocation = (sec->output_section->vma
1756 + sec->output_offset
1757 + sym->st_value);
1758 }
1759 else
1760 {
1761 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1762 while (h->root.type == bfd_link_hash_indirect
1763 || h->root.type == bfd_link_hash_warning)
1764 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1765
1766 relocation = 0;
1767 if (h->root.type == bfd_link_hash_defined
1768 || h->root.type == bfd_link_hash_defweak)
1769 {
1770 sec = h->root.u.def.section;
1771 if (sec->output_section == NULL)
1772 /* Set a flag that will be cleared later if we find a
1773 relocation value for this symbol. output_section
1774 is typically NULL for symbols satisfied by a shared
1775 library. */
1776 unresolved_reloc = true;
1777 else
1778 relocation = (h->root.u.def.value
1779 + sec->output_section->vma
1780 + sec->output_offset);
1781 }
1782 else if (h->root.type == bfd_link_hash_undefweak)
1783 ;
1784 else if (info->shared
1785 && (!info->symbolic || info->allow_shlib_undefined)
1786 && !info->no_undefined
1787 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1788 ;
1789 else
1790 {
1791 if (! ((*info->callbacks->undefined_symbol)
1792 (info, h->root.root.string, input_bfd,
1793 input_section, rel->r_offset,
1794 (!info->shared || info->no_undefined
1795 || ELF_ST_VISIBILITY (h->other)))))
1796 return false;
1797 }
1798 }
1799
1800 switch (r_type)
1801 {
1802 case R_386_GOT32:
1803 /* Relocation is to the entry for this symbol in the global
1804 offset table. */
1805 if (htab->sgot == NULL)
1806 abort ();
1807
1808 if (h != NULL)
1809 {
1810 boolean dyn;
1811
1812 off = h->got.offset;
1813 dyn = htab->elf.dynamic_sections_created;
1814 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)
1815 || (info->shared
1816 && (info->symbolic
1817 || h->dynindx == -1
1818 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
1819 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1820 {
1821 /* This is actually a static link, or it is a
1822 -Bsymbolic link and the symbol is defined
1823 locally, or the symbol was forced to be local
1824 because of a version file. We must initialize
1825 this entry in the global offset table. Since the
1826 offset must always be a multiple of 4, we use the
1827 least significant bit to record whether we have
1828 initialized it already.
1829
1830 When doing a dynamic link, we create a .rel.got
1831 relocation entry to initialize the value. This
1832 is done in the finish_dynamic_symbol routine. */
1833 if ((off & 1) != 0)
1834 off &= ~1;
1835 else
1836 {
1837 bfd_put_32 (output_bfd, relocation,
1838 htab->sgot->contents + off);
1839 h->got.offset |= 1;
1840 }
1841 }
1842 else
1843 unresolved_reloc = false;
1844 }
1845 else
1846 {
1847 if (local_got_offsets == NULL)
1848 abort ();
1849
1850 off = local_got_offsets[r_symndx];
1851
1852 /* The offset must always be a multiple of 4. We use
1853 the least significant bit to record whether we have
1854 already generated the necessary reloc. */
1855 if ((off & 1) != 0)
1856 off &= ~1;
1857 else
1858 {
1859 bfd_put_32 (output_bfd, relocation,
1860 htab->sgot->contents + off);
1861
1862 if (info->shared)
1863 {
1864 asection *srelgot;
1865 Elf_Internal_Rel outrel;
1866
1867 srelgot = htab->srelgot;
1868 if (srelgot == NULL)
1869 abort ();
1870
1871 outrel.r_offset = (htab->sgot->output_section->vma
1872 + htab->sgot->output_offset
1873 + off);
1874 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
1875 bfd_elf32_swap_reloc_out (output_bfd, &outrel,
1876 (((Elf32_External_Rel *)
1877 srelgot->contents)
1878 + srelgot->reloc_count));
1879 ++srelgot->reloc_count;
1880 }
1881
1882 local_got_offsets[r_symndx] |= 1;
1883 }
1884 }
1885
1886 if (off >= (bfd_vma) -2)
1887 abort ();
1888
1889 relocation = htab->sgot->output_offset + off;
1890 break;
1891
1892 case R_386_GOTOFF:
1893 /* Relocation is relative to the start of the global offset
1894 table. */
1895
1896 /* Note that sgot->output_offset is not involved in this
1897 calculation. We always want the start of .got. If we
1898 defined _GLOBAL_OFFSET_TABLE in a different way, as is
1899 permitted by the ABI, we might have to change this
1900 calculation. */
1901 relocation -= htab->sgot->output_section->vma;
1902 break;
1903
1904 case R_386_GOTPC:
1905 /* Use global offset table as symbol value. */
1906 relocation = htab->sgot->output_section->vma;
1907 unresolved_reloc = false;
1908 break;
1909
1910 case R_386_PLT32:
1911 /* Relocation is to the entry for this symbol in the
1912 procedure linkage table. */
1913
1914 /* Resolve a PLT32 reloc against a local symbol directly,
1915 without using the procedure linkage table. */
1916 if (h == NULL)
1917 break;
1918
1919 if (h->plt.offset == (bfd_vma) -1
1920 || htab->splt == NULL)
1921 {
1922 /* We didn't make a PLT entry for this symbol. This
1923 happens when statically linking PIC code, or when
1924 using -Bsymbolic. */
1925 break;
1926 }
1927
1928 relocation = (htab->splt->output_section->vma
1929 + htab->splt->output_offset
1930 + h->plt.offset);
1931 unresolved_reloc = false;
1932 break;
1933
1934 case R_386_32:
1935 case R_386_PC32:
1936 if ((info->shared
1937 && (input_section->flags & SEC_ALLOC) != 0
1938 && (r_type != R_386_PC32
1939 || (h != NULL
1940 && h->dynindx != -1
1941 && (! info->symbolic
1942 || (h->elf_link_hash_flags
1943 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1944 || (!info->shared
1945 && (input_section->flags & SEC_ALLOC) != 0
1946 && h != NULL
1947 && h->dynindx != -1
1948 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1949 && (((h->elf_link_hash_flags
1950 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1951 && (h->elf_link_hash_flags
1952 & ELF_LINK_HASH_DEF_REGULAR) == 0)
1953 || h->root.type == bfd_link_hash_undefweak
1954 || h->root.type == bfd_link_hash_undefined)))
1955 {
1956 Elf_Internal_Rel outrel;
1957 boolean skip, relocate;
1958 asection *sreloc;
1959 Elf32_External_Rel *loc;
1960
1961 /* When generating a shared object, these relocations
1962 are copied into the output file to be resolved at run
1963 time. */
1964
1965 skip = false;
1966
1967 if (elf_section_data (input_section)->stab_info == NULL)
1968 outrel.r_offset = rel->r_offset;
1969 else
1970 {
1971 off = (_bfd_stab_section_offset
1972 (output_bfd, htab->elf.stab_info, input_section,
1973 &elf_section_data (input_section)->stab_info,
1974 rel->r_offset));
1975 if (off == (bfd_vma) -1)
1976 skip = true;
1977 outrel.r_offset = off;
1978 }
1979
1980 outrel.r_offset += (input_section->output_section->vma
1981 + input_section->output_offset);
1982
1983 if (skip)
1984 {
1985 memset (&outrel, 0, sizeof outrel);
1986 relocate = false;
1987 }
1988 else if (h != NULL
1989 && h->dynindx != -1
1990 && (r_type == R_386_PC32
1991 || !info->shared
1992 || !info->symbolic
1993 || (h->elf_link_hash_flags
1994 & ELF_LINK_HASH_DEF_REGULAR) == 0))
1995
1996 {
1997 relocate = false;
1998 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
1999 }
2000 else
2001 {
2002 /* This symbol is local, or marked to become local. */
2003 relocate = true;
2004 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2005 }
2006
2007 sreloc = elf_section_data (input_section)->sreloc;
2008 if (sreloc == NULL)
2009 abort ();
2010
2011 loc = ((Elf32_External_Rel *) sreloc->contents
2012 + sreloc->reloc_count);
2013 sreloc->reloc_count += 1;
2014 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2015
2016 /* If this reloc is against an external symbol, we do
2017 not want to fiddle with the addend. Otherwise, we
2018 need to include the symbol value so that it becomes
2019 an addend for the dynamic reloc. */
2020 if (! relocate)
2021 continue;
2022 }
2023
2024 break;
2025
2026 default:
2027 break;
2028 }
2029
2030 /* FIXME: Why do we allow debugging sections to escape this error?
2031 More importantly, why do we not emit dynamic relocs for
2032 R_386_32 above in debugging sections (which are ! SEC_ALLOC)?
2033 If we had emitted the dynamic reloc, we could remove the
2034 fudge here. */
2035 if (unresolved_reloc
2036 && !(info->shared
2037 && (input_section->flags & SEC_DEBUGGING) != 0
2038 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2039 (*_bfd_error_handler)
2040 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2041 bfd_archive_filename (input_bfd),
2042 bfd_get_section_name (input_bfd, input_section),
2043 (long) rel->r_offset,
2044 h->root.root.string);
2045
2046 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2047 contents, rel->r_offset,
2048 relocation, (bfd_vma) 0);
2049
2050 switch (r)
2051 {
2052 case bfd_reloc_ok:
2053 break;
2054
2055 case bfd_reloc_overflow:
2056 {
2057 const char *name;
2058
2059 if (h != NULL)
2060 name = h->root.root.string;
2061 else
2062 {
2063 name = bfd_elf_string_from_elf_section (input_bfd,
2064 symtab_hdr->sh_link,
2065 sym->st_name);
2066 if (name == NULL)
2067 return false;
2068 if (*name == '\0')
2069 name = bfd_section_name (input_bfd, sec);
2070 }
2071 if (! ((*info->callbacks->reloc_overflow)
2072 (info, name, howto->name, (bfd_vma) 0,
2073 input_bfd, input_section, rel->r_offset)))
2074 return false;
2075 }
2076 break;
2077
2078 default:
2079 case bfd_reloc_outofrange:
2080 abort ();
2081 break;
2082 }
2083 }
2084
2085 return true;
2086 }
2087
2088 /* Finish up dynamic symbol handling. We set the contents of various
2089 dynamic sections here. */
2090
2091 static boolean
2092 elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
2093 bfd *output_bfd;
2094 struct bfd_link_info *info;
2095 struct elf_link_hash_entry *h;
2096 Elf_Internal_Sym *sym;
2097 {
2098 struct elf_i386_link_hash_table *htab;
2099 bfd *dynobj;
2100
2101 htab = elf_i386_hash_table (info);
2102 dynobj = htab->elf.dynobj;
2103
2104 if (h->plt.offset != (bfd_vma) -1)
2105 {
2106 bfd_vma plt_index;
2107 bfd_vma got_offset;
2108 Elf_Internal_Rel rel;
2109
2110 /* This symbol has an entry in the procedure linkage table. Set
2111 it up. */
2112
2113 if (h->dynindx == -1
2114 || htab->splt == NULL
2115 || htab->sgotplt == NULL
2116 || htab->srelplt == NULL)
2117 abort ();
2118
2119 /* Get the index in the procedure linkage table which
2120 corresponds to this symbol. This is the index of this symbol
2121 in all the symbols for which we are making plt entries. The
2122 first entry in the procedure linkage table is reserved. */
2123 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2124
2125 /* Get the offset into the .got table of the entry that
2126 corresponds to this function. Each .got entry is 4 bytes.
2127 The first three are reserved. */
2128 got_offset = (plt_index + 3) * 4;
2129
2130 /* Fill in the entry in the procedure linkage table. */
2131 if (! info->shared)
2132 {
2133 memcpy (htab->splt->contents + h->plt.offset, elf_i386_plt_entry,
2134 PLT_ENTRY_SIZE);
2135 bfd_put_32 (output_bfd,
2136 (htab->sgotplt->output_section->vma
2137 + htab->sgotplt->output_offset
2138 + got_offset),
2139 htab->splt->contents + h->plt.offset + 2);
2140 }
2141 else
2142 {
2143 memcpy (htab->splt->contents + h->plt.offset, elf_i386_pic_plt_entry,
2144 PLT_ENTRY_SIZE);
2145 bfd_put_32 (output_bfd, got_offset,
2146 htab->splt->contents + h->plt.offset + 2);
2147 }
2148
2149 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
2150 htab->splt->contents + h->plt.offset + 7);
2151 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2152 htab->splt->contents + h->plt.offset + 12);
2153
2154 /* Fill in the entry in the global offset table. */
2155 bfd_put_32 (output_bfd,
2156 (htab->splt->output_section->vma
2157 + htab->splt->output_offset
2158 + h->plt.offset
2159 + 6),
2160 htab->sgotplt->contents + got_offset);
2161
2162 /* Fill in the entry in the .rel.plt section. */
2163 rel.r_offset = (htab->sgotplt->output_section->vma
2164 + htab->sgotplt->output_offset
2165 + got_offset);
2166 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
2167 bfd_elf32_swap_reloc_out (output_bfd, &rel,
2168 ((Elf32_External_Rel *) htab->srelplt->contents
2169 + plt_index));
2170
2171 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2172 {
2173 /* Mark the symbol as undefined, rather than as defined in
2174 the .plt section. Leave the value alone. */
2175 sym->st_shndx = SHN_UNDEF;
2176 }
2177 }
2178
2179 if (h->got.offset != (bfd_vma) -1)
2180 {
2181 Elf_Internal_Rel rel;
2182
2183 /* This symbol has an entry in the global offset table. Set it
2184 up. */
2185
2186 if (htab->sgot == NULL || htab->srelgot == NULL)
2187 abort ();
2188
2189 rel.r_offset = (htab->sgot->output_section->vma
2190 + htab->sgot->output_offset
2191 + (h->got.offset & ~(bfd_vma) 1));
2192
2193 /* If this is a static link, or it is a -Bsymbolic link and the
2194 symbol is defined locally or was forced to be local because
2195 of a version file, we just want to emit a RELATIVE reloc.
2196 The entry in the global offset table will already have been
2197 initialized in the relocate_section function. */
2198 if (info->shared
2199 && (info->symbolic
2200 || h->dynindx == -1
2201 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
2202 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
2203 {
2204 BFD_ASSERT((h->got.offset & 1) != 0);
2205 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2206 }
2207 else
2208 {
2209 BFD_ASSERT((h->got.offset & 1) == 0);
2210 bfd_put_32 (output_bfd, (bfd_vma) 0,
2211 htab->sgot->contents + h->got.offset);
2212 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
2213 }
2214
2215 bfd_elf32_swap_reloc_out (output_bfd, &rel,
2216 ((Elf32_External_Rel *) htab->srelgot->contents
2217 + htab->srelgot->reloc_count));
2218 ++htab->srelgot->reloc_count;
2219 }
2220
2221 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2222 {
2223 Elf_Internal_Rel rel;
2224
2225 /* This symbol needs a copy reloc. Set it up. */
2226
2227 if (h->dynindx == -1
2228 || (h->root.type != bfd_link_hash_defined
2229 && h->root.type != bfd_link_hash_defweak)
2230 || htab->srelbss == NULL)
2231 abort ();
2232
2233 rel.r_offset = (h->root.u.def.value
2234 + h->root.u.def.section->output_section->vma
2235 + h->root.u.def.section->output_offset);
2236 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
2237 bfd_elf32_swap_reloc_out (output_bfd, &rel,
2238 ((Elf32_External_Rel *) htab->srelbss->contents
2239 + htab->srelbss->reloc_count));
2240 ++htab->srelbss->reloc_count;
2241 }
2242
2243 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2244 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2245 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2246 sym->st_shndx = SHN_ABS;
2247
2248 return true;
2249 }
2250
2251 /* Used to decide how to sort relocs in an optimal manner for the
2252 dynamic linker, before writing them out. */
2253
2254 static enum elf_reloc_type_class
2255 elf_i386_reloc_type_class (rela)
2256 const Elf_Internal_Rela *rela;
2257 {
2258 switch ((int) ELF32_R_TYPE (rela->r_info))
2259 {
2260 case R_386_RELATIVE:
2261 return reloc_class_relative;
2262 case R_386_JUMP_SLOT:
2263 return reloc_class_plt;
2264 case R_386_COPY:
2265 return reloc_class_copy;
2266 default:
2267 return reloc_class_normal;
2268 }
2269 }
2270
2271 /* Finish up the dynamic sections. */
2272
2273 static boolean
2274 elf_i386_finish_dynamic_sections (output_bfd, info)
2275 bfd *output_bfd;
2276 struct bfd_link_info *info;
2277 {
2278 struct elf_i386_link_hash_table *htab;
2279 bfd *dynobj;
2280 asection *sdyn;
2281
2282 htab = elf_i386_hash_table (info);
2283 dynobj = htab->elf.dynobj;
2284 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2285
2286 if (htab->elf.dynamic_sections_created)
2287 {
2288 Elf32_External_Dyn *dyncon, *dynconend;
2289
2290 if (sdyn == NULL || htab->sgot == NULL)
2291 abort ();
2292
2293 dyncon = (Elf32_External_Dyn *) sdyn->contents;
2294 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2295 for (; dyncon < dynconend; dyncon++)
2296 {
2297 Elf_Internal_Dyn dyn;
2298
2299 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
2300
2301 switch (dyn.d_tag)
2302 {
2303 default:
2304 break;
2305
2306 case DT_PLTGOT:
2307 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2308 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
2309 break;
2310
2311 case DT_JMPREL:
2312 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2313 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
2314 break;
2315
2316 case DT_PLTRELSZ:
2317 if (htab->srelplt->output_section->_cooked_size != 0)
2318 dyn.d_un.d_val = htab->srelplt->output_section->_cooked_size;
2319 else
2320 dyn.d_un.d_val = htab->srelplt->output_section->_raw_size;
2321 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
2322 break;
2323
2324 case DT_RELSZ:
2325 /* My reading of the SVR4 ABI indicates that the
2326 procedure linkage table relocs (DT_JMPREL) should be
2327 included in the overall relocs (DT_REL). This is
2328 what Solaris does. However, UnixWare can not handle
2329 that case. Therefore, we override the DT_RELSZ entry
2330 here to make it not include the JMPREL relocs. Since
2331 the linker script arranges for .rel.plt to follow all
2332 other relocation sections, we don't have to worry
2333 about changing the DT_REL entry. */
2334 if (htab->srelplt != NULL)
2335 {
2336 if (htab->srelplt->output_section->_cooked_size != 0)
2337 dyn.d_un.d_val -= htab->srelplt->output_section->_cooked_size;
2338 else
2339 dyn.d_un.d_val -= htab->srelplt->output_section->_raw_size;
2340 }
2341 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
2342 break;
2343 }
2344 }
2345
2346 /* Fill in the first entry in the procedure linkage table. */
2347 if (htab->splt && htab->splt->_raw_size > 0)
2348 {
2349 if (info->shared)
2350 memcpy (htab->splt->contents,
2351 elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
2352 else
2353 {
2354 memcpy (htab->splt->contents,
2355 elf_i386_plt0_entry, PLT_ENTRY_SIZE);
2356 bfd_put_32 (output_bfd,
2357 (htab->sgotplt->output_section->vma
2358 + htab->sgotplt->output_offset
2359 + 4),
2360 htab->splt->contents + 2);
2361 bfd_put_32 (output_bfd,
2362 (htab->sgotplt->output_section->vma
2363 + htab->sgotplt->output_offset
2364 + 8),
2365 htab->splt->contents + 8);
2366 }
2367
2368 /* UnixWare sets the entsize of .plt to 4, although that doesn't
2369 really seem like the right value. */
2370 elf_section_data (htab->splt->output_section)
2371 ->this_hdr.sh_entsize = 4;
2372 }
2373 }
2374
2375 if (htab->sgotplt)
2376 {
2377 /* Fill in the first three entries in the global offset table. */
2378 if (htab->sgotplt->_raw_size > 0)
2379 {
2380 bfd_put_32 (output_bfd,
2381 (sdyn == NULL ? (bfd_vma) 0
2382 : sdyn->output_section->vma + sdyn->output_offset),
2383 htab->sgotplt->contents);
2384 bfd_put_32 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 4);
2385 bfd_put_32 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 8);
2386 }
2387
2388 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4;
2389 }
2390 return true;
2391 }
2392
2393 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
2394 #define TARGET_LITTLE_NAME "elf32-i386"
2395 #define ELF_ARCH bfd_arch_i386
2396 #define ELF_MACHINE_CODE EM_386
2397 #define ELF_MAXPAGESIZE 0x1000
2398
2399 #define elf_backend_can_gc_sections 1
2400 #define elf_backend_want_got_plt 1
2401 #define elf_backend_plt_readonly 1
2402 #define elf_backend_want_plt_sym 0
2403 #define elf_backend_got_header_size 12
2404 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2405
2406 #define elf_info_to_howto elf_i386_info_to_howto
2407 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
2408
2409 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
2410 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
2411 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
2412
2413 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol
2414 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol
2415 #define elf_backend_check_relocs elf_i386_check_relocs
2416 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections
2417 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections
2418 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol
2419 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
2420 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
2421 #define elf_backend_relocate_section elf_i386_relocate_section
2422 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections
2423 #define elf_backend_fake_sections elf_i386_fake_sections
2424 #define elf_backend_grok_prstatus elf_i386_grok_prstatus
2425 #define elf_backend_grok_psinfo elf_i386_grok_psinfo
2426 #define elf_backend_reloc_type_class elf_i386_reloc_type_class
2427
2428 #include "elf32-target.h"
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