* elf32-i386.c (elf_howto_table): Comments.
[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, 2002
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 elf_i386_copy_indirect_symbol
48 PARAMS ((struct elf_link_hash_entry *, struct elf_link_hash_entry *));
49 static boolean elf_i386_check_relocs
50 PARAMS ((bfd *, struct bfd_link_info *, asection *,
51 const Elf_Internal_Rela *));
52 static asection *elf_i386_gc_mark_hook
53 PARAMS ((bfd *, struct bfd_link_info *, Elf_Internal_Rela *,
54 struct elf_link_hash_entry *, Elf_Internal_Sym *));
55 static boolean elf_i386_gc_sweep_hook
56 PARAMS ((bfd *, struct bfd_link_info *, asection *,
57 const Elf_Internal_Rela *));
58 static boolean elf_i386_adjust_dynamic_symbol
59 PARAMS ((struct bfd_link_info *, struct elf_link_hash_entry *));
60 static boolean allocate_dynrelocs
61 PARAMS ((struct elf_link_hash_entry *, PTR));
62 static boolean readonly_dynrelocs
63 PARAMS ((struct elf_link_hash_entry *, PTR));
64 static boolean elf_i386_fake_sections
65 PARAMS ((bfd *, Elf32_Internal_Shdr *, asection *));
66 static boolean elf_i386_size_dynamic_sections
67 PARAMS ((bfd *, struct bfd_link_info *));
68 static boolean elf_i386_relocate_section
69 PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
70 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
71 static boolean elf_i386_finish_dynamic_symbol
72 PARAMS ((bfd *, struct bfd_link_info *, struct elf_link_hash_entry *,
73 Elf_Internal_Sym *));
74 static enum elf_reloc_type_class elf_i386_reloc_type_class
75 PARAMS ((const Elf_Internal_Rela *));
76 static boolean elf_i386_finish_dynamic_sections
77 PARAMS ((bfd *, struct bfd_link_info *));
78
79 #define USE_REL 1 /* 386 uses REL relocations instead of RELA */
80
81 #include "elf/i386.h"
82
83 static reloc_howto_type elf_howto_table[]=
84 {
85 HOWTO(R_386_NONE, 0, 0, 0, false, 0, complain_overflow_bitfield,
86 bfd_elf_generic_reloc, "R_386_NONE",
87 true, 0x00000000, 0x00000000, false),
88 HOWTO(R_386_32, 0, 2, 32, false, 0, complain_overflow_bitfield,
89 bfd_elf_generic_reloc, "R_386_32",
90 true, 0xffffffff, 0xffffffff, false),
91 HOWTO(R_386_PC32, 0, 2, 32, true, 0, complain_overflow_bitfield,
92 bfd_elf_generic_reloc, "R_386_PC32",
93 true, 0xffffffff, 0xffffffff, true),
94 HOWTO(R_386_GOT32, 0, 2, 32, false, 0, complain_overflow_bitfield,
95 bfd_elf_generic_reloc, "R_386_GOT32",
96 true, 0xffffffff, 0xffffffff, false),
97 HOWTO(R_386_PLT32, 0, 2, 32, true, 0, complain_overflow_bitfield,
98 bfd_elf_generic_reloc, "R_386_PLT32",
99 true, 0xffffffff, 0xffffffff, true),
100 HOWTO(R_386_COPY, 0, 2, 32, false, 0, complain_overflow_bitfield,
101 bfd_elf_generic_reloc, "R_386_COPY",
102 true, 0xffffffff, 0xffffffff, false),
103 HOWTO(R_386_GLOB_DAT, 0, 2, 32, false, 0, complain_overflow_bitfield,
104 bfd_elf_generic_reloc, "R_386_GLOB_DAT",
105 true, 0xffffffff, 0xffffffff, false),
106 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, false, 0, complain_overflow_bitfield,
107 bfd_elf_generic_reloc, "R_386_JUMP_SLOT",
108 true, 0xffffffff, 0xffffffff, false),
109 HOWTO(R_386_RELATIVE, 0, 2, 32, false, 0, complain_overflow_bitfield,
110 bfd_elf_generic_reloc, "R_386_RELATIVE",
111 true, 0xffffffff, 0xffffffff, false),
112 HOWTO(R_386_GOTOFF, 0, 2, 32, false, 0, complain_overflow_bitfield,
113 bfd_elf_generic_reloc, "R_386_GOTOFF",
114 true, 0xffffffff, 0xffffffff, false),
115 HOWTO(R_386_GOTPC, 0, 2, 32, true, 0, complain_overflow_bitfield,
116 bfd_elf_generic_reloc, "R_386_GOTPC",
117 true, 0xffffffff, 0xffffffff, true),
118
119 /* We have a gap in the reloc numbers here.
120 R_386_standard counts the number up to this point, and
121 R_386_ext_offset is the value to subtract from a reloc type of
122 R_386_16 thru R_386_PC8 to form an index into this table. */
123 #define R_386_standard ((unsigned int) R_386_GOTPC + 1)
124 #define R_386_ext_offset ((unsigned int) R_386_16 - R_386_standard)
125
126 /* The remaining relocs are a GNU extension. */
127 HOWTO(R_386_16, 0, 1, 16, false, 0, complain_overflow_bitfield,
128 bfd_elf_generic_reloc, "R_386_16",
129 true, 0xffff, 0xffff, false),
130 HOWTO(R_386_PC16, 0, 1, 16, true, 0, complain_overflow_bitfield,
131 bfd_elf_generic_reloc, "R_386_PC16",
132 true, 0xffff, 0xffff, true),
133 HOWTO(R_386_8, 0, 0, 8, false, 0, complain_overflow_bitfield,
134 bfd_elf_generic_reloc, "R_386_8",
135 true, 0xff, 0xff, false),
136 HOWTO(R_386_PC8, 0, 0, 8, true, 0, complain_overflow_signed,
137 bfd_elf_generic_reloc, "R_386_PC8",
138 true, 0xff, 0xff, true),
139
140 /* Another gap. */
141 #define R_386_ext ((unsigned int) R_386_PC8 + 1 - R_386_ext_offset)
142 #define R_386_vt_offset ((unsigned int) R_386_GNU_VTINHERIT - R_386_ext)
143
144 /* GNU extension to record C++ vtable hierarchy. */
145 HOWTO (R_386_GNU_VTINHERIT, /* type */
146 0, /* rightshift */
147 2, /* size (0 = byte, 1 = short, 2 = long) */
148 0, /* bitsize */
149 false, /* pc_relative */
150 0, /* bitpos */
151 complain_overflow_dont, /* complain_on_overflow */
152 NULL, /* special_function */
153 "R_386_GNU_VTINHERIT", /* name */
154 false, /* partial_inplace */
155 0, /* src_mask */
156 0, /* dst_mask */
157 false), /* pcrel_offset */
158
159 /* GNU extension to record C++ vtable member usage. */
160 HOWTO (R_386_GNU_VTENTRY, /* type */
161 0, /* rightshift */
162 2, /* size (0 = byte, 1 = short, 2 = long) */
163 0, /* bitsize */
164 false, /* pc_relative */
165 0, /* bitpos */
166 complain_overflow_dont, /* complain_on_overflow */
167 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
168 "R_386_GNU_VTENTRY", /* name */
169 false, /* partial_inplace */
170 0, /* src_mask */
171 0, /* dst_mask */
172 false) /* pcrel_offset */
173
174 #define R_386_vt ((unsigned int) R_386_GNU_VTENTRY + 1 - R_386_vt_offset)
175
176 };
177
178 #ifdef DEBUG_GEN_RELOC
179 #define TRACE(str) fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
180 #else
181 #define TRACE(str)
182 #endif
183
184 static reloc_howto_type *
185 elf_i386_reloc_type_lookup (abfd, code)
186 bfd *abfd ATTRIBUTE_UNUSED;
187 bfd_reloc_code_real_type code;
188 {
189 switch (code)
190 {
191 case BFD_RELOC_NONE:
192 TRACE ("BFD_RELOC_NONE");
193 return &elf_howto_table[(unsigned int) R_386_NONE ];
194
195 case BFD_RELOC_32:
196 TRACE ("BFD_RELOC_32");
197 return &elf_howto_table[(unsigned int) R_386_32 ];
198
199 case BFD_RELOC_CTOR:
200 TRACE ("BFD_RELOC_CTOR");
201 return &elf_howto_table[(unsigned int) R_386_32 ];
202
203 case BFD_RELOC_32_PCREL:
204 TRACE ("BFD_RELOC_PC32");
205 return &elf_howto_table[(unsigned int) R_386_PC32 ];
206
207 case BFD_RELOC_386_GOT32:
208 TRACE ("BFD_RELOC_386_GOT32");
209 return &elf_howto_table[(unsigned int) R_386_GOT32 ];
210
211 case BFD_RELOC_386_PLT32:
212 TRACE ("BFD_RELOC_386_PLT32");
213 return &elf_howto_table[(unsigned int) R_386_PLT32 ];
214
215 case BFD_RELOC_386_COPY:
216 TRACE ("BFD_RELOC_386_COPY");
217 return &elf_howto_table[(unsigned int) R_386_COPY ];
218
219 case BFD_RELOC_386_GLOB_DAT:
220 TRACE ("BFD_RELOC_386_GLOB_DAT");
221 return &elf_howto_table[(unsigned int) R_386_GLOB_DAT ];
222
223 case BFD_RELOC_386_JUMP_SLOT:
224 TRACE ("BFD_RELOC_386_JUMP_SLOT");
225 return &elf_howto_table[(unsigned int) R_386_JUMP_SLOT ];
226
227 case BFD_RELOC_386_RELATIVE:
228 TRACE ("BFD_RELOC_386_RELATIVE");
229 return &elf_howto_table[(unsigned int) R_386_RELATIVE ];
230
231 case BFD_RELOC_386_GOTOFF:
232 TRACE ("BFD_RELOC_386_GOTOFF");
233 return &elf_howto_table[(unsigned int) R_386_GOTOFF ];
234
235 case BFD_RELOC_386_GOTPC:
236 TRACE ("BFD_RELOC_386_GOTPC");
237 return &elf_howto_table[(unsigned int) R_386_GOTPC ];
238
239 /* The remaining relocs are a GNU extension. */
240 case BFD_RELOC_16:
241 TRACE ("BFD_RELOC_16");
242 return &elf_howto_table[(unsigned int) R_386_16 - R_386_ext_offset];
243
244 case BFD_RELOC_16_PCREL:
245 TRACE ("BFD_RELOC_16_PCREL");
246 return &elf_howto_table[(unsigned int) R_386_PC16 - R_386_ext_offset];
247
248 case BFD_RELOC_8:
249 TRACE ("BFD_RELOC_8");
250 return &elf_howto_table[(unsigned int) R_386_8 - R_386_ext_offset];
251
252 case BFD_RELOC_8_PCREL:
253 TRACE ("BFD_RELOC_8_PCREL");
254 return &elf_howto_table[(unsigned int) R_386_PC8 - R_386_ext_offset];
255
256 case BFD_RELOC_VTABLE_INHERIT:
257 TRACE ("BFD_RELOC_VTABLE_INHERIT");
258 return &elf_howto_table[(unsigned int) R_386_GNU_VTINHERIT
259 - R_386_vt_offset];
260
261 case BFD_RELOC_VTABLE_ENTRY:
262 TRACE ("BFD_RELOC_VTABLE_ENTRY");
263 return &elf_howto_table[(unsigned int) R_386_GNU_VTENTRY
264 - R_386_vt_offset];
265
266 default:
267 break;
268 }
269
270 TRACE ("Unknown");
271 return 0;
272 }
273
274 static void
275 elf_i386_info_to_howto (abfd, cache_ptr, dst)
276 bfd *abfd ATTRIBUTE_UNUSED;
277 arelent *cache_ptr ATTRIBUTE_UNUSED;
278 Elf32_Internal_Rela *dst ATTRIBUTE_UNUSED;
279 {
280 abort ();
281 }
282
283 static void
284 elf_i386_info_to_howto_rel (abfd, cache_ptr, dst)
285 bfd *abfd ATTRIBUTE_UNUSED;
286 arelent *cache_ptr;
287 Elf32_Internal_Rel *dst;
288 {
289 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
290 unsigned int indx;
291
292 if ((indx = r_type) >= R_386_standard
293 && ((indx = r_type - R_386_ext_offset) - R_386_standard
294 >= R_386_ext - R_386_standard)
295 && ((indx = r_type - R_386_vt_offset) - R_386_ext
296 >= R_386_vt - R_386_ext))
297 {
298 (*_bfd_error_handler) (_("%s: invalid relocation type %d"),
299 bfd_archive_filename (abfd), (int) r_type);
300 indx = (unsigned int) R_386_NONE;
301 }
302 cache_ptr->howto = &elf_howto_table[indx];
303 }
304
305 /* Return whether a symbol name implies a local label. The UnixWare
306 2.1 cc generates temporary symbols that start with .X, so we
307 recognize them here. FIXME: do other SVR4 compilers also use .X?.
308 If so, we should move the .X recognition into
309 _bfd_elf_is_local_label_name. */
310
311 static boolean
312 elf_i386_is_local_label_name (abfd, name)
313 bfd *abfd;
314 const char *name;
315 {
316 if (name[0] == '.' && name[1] == 'X')
317 return true;
318
319 return _bfd_elf_is_local_label_name (abfd, name);
320 }
321 \f
322 /* Support for core dump NOTE sections. */
323 static boolean
324 elf_i386_grok_prstatus (abfd, note)
325 bfd *abfd;
326 Elf_Internal_Note *note;
327 {
328 int offset;
329 size_t raw_size;
330
331 switch (note->descsz)
332 {
333 default:
334 return false;
335
336 case 144: /* Linux/i386 */
337 /* pr_cursig */
338 elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12);
339
340 /* pr_pid */
341 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
342
343 /* pr_reg */
344 offset = 72;
345 raw_size = 68;
346
347 break;
348 }
349
350 /* Make a ".reg/999" section. */
351 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
352 raw_size, note->descpos + offset);
353 }
354
355 static boolean
356 elf_i386_grok_psinfo (abfd, note)
357 bfd *abfd;
358 Elf_Internal_Note *note;
359 {
360 switch (note->descsz)
361 {
362 default:
363 return false;
364
365 case 124: /* Linux/i386 elf_prpsinfo */
366 elf_tdata (abfd)->core_program
367 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
368 elf_tdata (abfd)->core_command
369 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
370 }
371
372 /* Note that for some reason, a spurious space is tacked
373 onto the end of the args in some (at least one anyway)
374 implementations, so strip it off if it exists. */
375
376 {
377 char *command = elf_tdata (abfd)->core_command;
378 int n = strlen (command);
379
380 if (0 < n && command[n - 1] == ' ')
381 command[n - 1] = '\0';
382 }
383
384 return true;
385 }
386 \f
387 /* Functions for the i386 ELF linker.
388
389 In order to gain some understanding of code in this file without
390 knowing all the intricate details of the linker, note the
391 following:
392
393 Functions named elf_i386_* are called by external routines, other
394 functions are only called locally. elf_i386_* functions appear
395 in this file more or less in the order in which they are called
396 from external routines. eg. elf_i386_check_relocs is called
397 early in the link process, elf_i386_finish_dynamic_sections is
398 one of the last functions. */
399
400
401 /* The name of the dynamic interpreter. This is put in the .interp
402 section. */
403
404 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
405
406 /* The size in bytes of an entry in the procedure linkage table. */
407
408 #define PLT_ENTRY_SIZE 16
409
410 /* The first entry in an absolute procedure linkage table looks like
411 this. See the SVR4 ABI i386 supplement to see how this works. */
412
413 static const bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
414 {
415 0xff, 0x35, /* pushl contents of address */
416 0, 0, 0, 0, /* replaced with address of .got + 4. */
417 0xff, 0x25, /* jmp indirect */
418 0, 0, 0, 0, /* replaced with address of .got + 8. */
419 0, 0, 0, 0 /* pad out to 16 bytes. */
420 };
421
422 /* Subsequent entries in an absolute procedure linkage table look like
423 this. */
424
425 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
426 {
427 0xff, 0x25, /* jmp indirect */
428 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
429 0x68, /* pushl immediate */
430 0, 0, 0, 0, /* replaced with offset into relocation table. */
431 0xe9, /* jmp relative */
432 0, 0, 0, 0 /* replaced with offset to start of .plt. */
433 };
434
435 /* The first entry in a PIC procedure linkage table look like this. */
436
437 static const bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
438 {
439 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
440 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
441 0, 0, 0, 0 /* pad out to 16 bytes. */
442 };
443
444 /* Subsequent entries in a PIC procedure linkage table look like this. */
445
446 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
447 {
448 0xff, 0xa3, /* jmp *offset(%ebx) */
449 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
450 0x68, /* pushl immediate */
451 0, 0, 0, 0, /* replaced with offset into relocation table. */
452 0xe9, /* jmp relative */
453 0, 0, 0, 0 /* replaced with offset to start of .plt. */
454 };
455
456 /* The i386 linker needs to keep track of the number of relocs that it
457 decides to copy as dynamic relocs in check_relocs for each symbol.
458 This is so that it can later discard them if they are found to be
459 unnecessary. We store the information in a field extending the
460 regular ELF linker hash table. */
461
462 struct elf_i386_dyn_relocs
463 {
464 struct elf_i386_dyn_relocs *next;
465
466 /* The input section of the reloc. */
467 asection *sec;
468
469 /* Total number of relocs copied for the input section. */
470 bfd_size_type count;
471
472 /* Number of pc-relative relocs copied for the input section. */
473 bfd_size_type pc_count;
474 };
475
476 /* i386 ELF linker hash entry. */
477
478 struct elf_i386_link_hash_entry
479 {
480 struct elf_link_hash_entry elf;
481
482 /* Track dynamic relocs copied for this symbol. */
483 struct elf_i386_dyn_relocs *dyn_relocs;
484 };
485
486 /* i386 ELF linker hash table. */
487
488 struct elf_i386_link_hash_table
489 {
490 struct elf_link_hash_table elf;
491
492 /* Short-cuts to get to dynamic linker sections. */
493 asection *sgot;
494 asection *sgotplt;
495 asection *srelgot;
496 asection *splt;
497 asection *srelplt;
498 asection *sdynbss;
499 asection *srelbss;
500
501 /* Small local sym to section mapping cache. */
502 struct sym_sec_cache sym_sec;
503 };
504
505 /* Get the i386 ELF linker hash table from a link_info structure. */
506
507 #define elf_i386_hash_table(p) \
508 ((struct elf_i386_link_hash_table *) ((p)->hash))
509
510 /* Create an entry in an i386 ELF linker hash table. */
511
512 static struct bfd_hash_entry *
513 link_hash_newfunc (entry, table, string)
514 struct bfd_hash_entry *entry;
515 struct bfd_hash_table *table;
516 const char *string;
517 {
518 /* Allocate the structure if it has not already been allocated by a
519 subclass. */
520 if (entry == NULL)
521 {
522 entry = bfd_hash_allocate (table,
523 sizeof (struct elf_i386_link_hash_entry));
524 if (entry == NULL)
525 return entry;
526 }
527
528 /* Call the allocation method of the superclass. */
529 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
530 if (entry != NULL)
531 {
532 struct elf_i386_link_hash_entry *eh;
533
534 eh = (struct elf_i386_link_hash_entry *) entry;
535 eh->dyn_relocs = NULL;
536 }
537
538 return entry;
539 }
540
541 /* Create an i386 ELF linker hash table. */
542
543 static struct bfd_link_hash_table *
544 elf_i386_link_hash_table_create (abfd)
545 bfd *abfd;
546 {
547 struct elf_i386_link_hash_table *ret;
548 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table);
549
550 ret = (struct elf_i386_link_hash_table *) bfd_malloc (amt);
551 if (ret == NULL)
552 return NULL;
553
554 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
555 {
556 free (ret);
557 return NULL;
558 }
559
560 ret->sgot = NULL;
561 ret->sgotplt = NULL;
562 ret->srelgot = NULL;
563 ret->splt = NULL;
564 ret->srelplt = NULL;
565 ret->sdynbss = NULL;
566 ret->srelbss = NULL;
567 ret->sym_sec.abfd = NULL;
568
569 return &ret->elf.root;
570 }
571
572 /* Create .got, .gotplt, and .rel.got sections in DYNOBJ, and set up
573 shortcuts to them in our hash table. */
574
575 static boolean
576 create_got_section (dynobj, info)
577 bfd *dynobj;
578 struct bfd_link_info *info;
579 {
580 struct elf_i386_link_hash_table *htab;
581
582 if (! _bfd_elf_create_got_section (dynobj, info))
583 return false;
584
585 htab = elf_i386_hash_table (info);
586 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
587 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
588 if (!htab->sgot || !htab->sgotplt)
589 abort ();
590
591 htab->srelgot = bfd_make_section (dynobj, ".rel.got");
592 if (htab->srelgot == NULL
593 || ! bfd_set_section_flags (dynobj, htab->srelgot,
594 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
595 | SEC_IN_MEMORY | SEC_LINKER_CREATED
596 | SEC_READONLY))
597 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2))
598 return false;
599 return true;
600 }
601
602 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and
603 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our
604 hash table. */
605
606 static boolean
607 elf_i386_create_dynamic_sections (dynobj, info)
608 bfd *dynobj;
609 struct bfd_link_info *info;
610 {
611 struct elf_i386_link_hash_table *htab;
612
613 htab = elf_i386_hash_table (info);
614 if (!htab->sgot && !create_got_section (dynobj, info))
615 return false;
616
617 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
618 return false;
619
620 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
621 htab->srelplt = bfd_get_section_by_name (dynobj, ".rel.plt");
622 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
623 if (!info->shared)
624 htab->srelbss = bfd_get_section_by_name (dynobj, ".rel.bss");
625
626 if (!htab->splt || !htab->srelplt || !htab->sdynbss
627 || (!info->shared && !htab->srelbss))
628 abort ();
629
630 return true;
631 }
632
633 /* Copy the extra info we tack onto an elf_link_hash_entry. */
634
635 static void
636 elf_i386_copy_indirect_symbol (dir, ind)
637 struct elf_link_hash_entry *dir, *ind;
638 {
639 struct elf_i386_link_hash_entry *edir, *eind;
640
641 edir = (struct elf_i386_link_hash_entry *) dir;
642 eind = (struct elf_i386_link_hash_entry *) ind;
643
644 if (eind->dyn_relocs != NULL)
645 {
646 if (edir->dyn_relocs != NULL)
647 {
648 struct elf_i386_dyn_relocs **pp;
649 struct elf_i386_dyn_relocs *p;
650
651 if (ind->root.type == bfd_link_hash_indirect)
652 abort ();
653
654 /* Add reloc counts against the weak sym to the strong sym
655 list. Merge any entries against the same section. */
656 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
657 {
658 struct elf_i386_dyn_relocs *q;
659
660 for (q = edir->dyn_relocs; q != NULL; q = q->next)
661 if (q->sec == p->sec)
662 {
663 q->pc_count += p->pc_count;
664 q->count += p->count;
665 *pp = p->next;
666 break;
667 }
668 if (q == NULL)
669 pp = &p->next;
670 }
671 *pp = edir->dyn_relocs;
672 }
673
674 edir->dyn_relocs = eind->dyn_relocs;
675 eind->dyn_relocs = NULL;
676 }
677
678 _bfd_elf_link_hash_copy_indirect (dir, ind);
679 }
680
681 /* Look through the relocs for a section during the first phase, and
682 calculate needed space in the global offset table, procedure linkage
683 table, and dynamic reloc sections. */
684
685 static boolean
686 elf_i386_check_relocs (abfd, info, sec, relocs)
687 bfd *abfd;
688 struct bfd_link_info *info;
689 asection *sec;
690 const Elf_Internal_Rela *relocs;
691 {
692 struct elf_i386_link_hash_table *htab;
693 Elf_Internal_Shdr *symtab_hdr;
694 struct elf_link_hash_entry **sym_hashes;
695 const Elf_Internal_Rela *rel;
696 const Elf_Internal_Rela *rel_end;
697 asection *sreloc;
698
699 if (info->relocateable)
700 return true;
701
702 htab = elf_i386_hash_table (info);
703 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
704 sym_hashes = elf_sym_hashes (abfd);
705
706 sreloc = NULL;
707
708 rel_end = relocs + sec->reloc_count;
709 for (rel = relocs; rel < rel_end; rel++)
710 {
711 unsigned long r_symndx;
712 struct elf_link_hash_entry *h;
713
714 r_symndx = ELF32_R_SYM (rel->r_info);
715
716 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
717 {
718 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
719 bfd_archive_filename (abfd),
720 r_symndx);
721 return false;
722 }
723
724 if (r_symndx < symtab_hdr->sh_info)
725 h = NULL;
726 else
727 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
728
729 switch (ELF32_R_TYPE (rel->r_info))
730 {
731 case R_386_GOT32:
732 /* This symbol requires a global offset table entry. */
733 if (h != NULL)
734 {
735 h->got.refcount += 1;
736 }
737 else
738 {
739 bfd_signed_vma *local_got_refcounts;
740
741 /* This is a global offset table entry for a local symbol. */
742 local_got_refcounts = elf_local_got_refcounts (abfd);
743 if (local_got_refcounts == NULL)
744 {
745 bfd_size_type size;
746
747 size = symtab_hdr->sh_info;
748 size *= sizeof (bfd_signed_vma);
749 local_got_refcounts = ((bfd_signed_vma *)
750 bfd_zalloc (abfd, size));
751 if (local_got_refcounts == NULL)
752 return false;
753 elf_local_got_refcounts (abfd) = local_got_refcounts;
754 }
755 local_got_refcounts[r_symndx] += 1;
756 }
757 /* Fall through */
758
759 case R_386_GOTOFF:
760 case R_386_GOTPC:
761 if (htab->sgot == NULL)
762 {
763 if (htab->elf.dynobj == NULL)
764 htab->elf.dynobj = abfd;
765 if (!create_got_section (htab->elf.dynobj, info))
766 return false;
767 }
768 break;
769
770 case R_386_PLT32:
771 /* This symbol requires a procedure linkage table entry. We
772 actually build the entry in adjust_dynamic_symbol,
773 because this might be a case of linking PIC code which is
774 never referenced by a dynamic object, in which case we
775 don't need to generate a procedure linkage table entry
776 after all. */
777
778 /* If this is a local symbol, we resolve it directly without
779 creating a procedure linkage table entry. */
780 if (h == NULL)
781 continue;
782
783 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
784 h->plt.refcount += 1;
785 break;
786
787 case R_386_32:
788 case R_386_PC32:
789 if (h != NULL && !info->shared)
790 {
791 /* If this reloc is in a read-only section, we might
792 need a copy reloc. We can't check reliably at this
793 stage whether the section is read-only, as input
794 sections have not yet been mapped to output sections.
795 Tentatively set the flag for now, and correct in
796 adjust_dynamic_symbol. */
797 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
798
799 /* We may need a .plt entry if the function this reloc
800 refers to is in a shared lib. */
801 h->plt.refcount += 1;
802 }
803
804 /* If we are creating a shared library, and this is a reloc
805 against a global symbol, or a non PC relative reloc
806 against a local symbol, then we need to copy the reloc
807 into the shared library. However, if we are linking with
808 -Bsymbolic, we do not need to copy a reloc against a
809 global symbol which is defined in an object we are
810 including in the link (i.e., DEF_REGULAR is set). At
811 this point we have not seen all the input files, so it is
812 possible that DEF_REGULAR is not set now but will be set
813 later (it is never cleared). In case of a weak definition,
814 DEF_REGULAR may be cleared later by a strong definition in
815 a shared library. We account for that possibility below by
816 storing information in the relocs_copied field of the hash
817 table entry. A similar situation occurs when creating
818 shared libraries and symbol visibility changes render the
819 symbol local.
820
821 If on the other hand, we are creating an executable, we
822 may need to keep relocations for symbols satisfied by a
823 dynamic library if we manage to avoid copy relocs for the
824 symbol. */
825 if ((info->shared
826 && (sec->flags & SEC_ALLOC) != 0
827 && (ELF32_R_TYPE (rel->r_info) != R_386_PC32
828 || (h != NULL
829 && (! info->symbolic
830 || h->root.type == bfd_link_hash_defweak
831 || (h->elf_link_hash_flags
832 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
833 || (!info->shared
834 && (sec->flags & SEC_ALLOC) != 0
835 && h != NULL
836 && (h->root.type == bfd_link_hash_defweak
837 || (h->elf_link_hash_flags
838 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
839 {
840 struct elf_i386_dyn_relocs *p;
841 struct elf_i386_dyn_relocs **head;
842
843 /* We must copy these reloc types into the output file.
844 Create a reloc section in dynobj and make room for
845 this reloc. */
846 if (sreloc == NULL)
847 {
848 const char *name;
849 bfd *dynobj;
850 unsigned int strndx = elf_elfheader (abfd)->e_shstrndx;
851 unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name;
852
853 name = bfd_elf_string_from_elf_section (abfd, strndx, shnam);
854 if (name == NULL)
855 return false;
856
857 if (strncmp (name, ".rel", 4) != 0
858 || strcmp (bfd_get_section_name (abfd, sec),
859 name + 4) != 0)
860 {
861 (*_bfd_error_handler)
862 (_("%s: bad relocation section name `%s\'"),
863 bfd_archive_filename (abfd), name);
864 }
865
866 if (htab->elf.dynobj == NULL)
867 htab->elf.dynobj = abfd;
868
869 dynobj = htab->elf.dynobj;
870 sreloc = bfd_get_section_by_name (dynobj, name);
871 if (sreloc == NULL)
872 {
873 flagword flags;
874
875 sreloc = bfd_make_section (dynobj, name);
876 flags = (SEC_HAS_CONTENTS | SEC_READONLY
877 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
878 if ((sec->flags & SEC_ALLOC) != 0)
879 flags |= SEC_ALLOC | SEC_LOAD;
880 if (sreloc == NULL
881 || ! bfd_set_section_flags (dynobj, sreloc, flags)
882 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
883 return false;
884 }
885 elf_section_data (sec)->sreloc = sreloc;
886 }
887
888 /* If this is a global symbol, we count the number of
889 relocations we need for this symbol. */
890 if (h != NULL)
891 {
892 head = &((struct elf_i386_link_hash_entry *) h)->dyn_relocs;
893 }
894 else
895 {
896 /* Track dynamic relocs needed for local syms too.
897 We really need local syms available to do this
898 easily. Oh well. */
899
900 asection *s;
901 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
902 sec, r_symndx);
903 if (s == NULL)
904 return false;
905
906 head = ((struct elf_i386_dyn_relocs **)
907 &elf_section_data (s)->local_dynrel);
908 }
909
910 p = *head;
911 if (p == NULL || p->sec != sec)
912 {
913 bfd_size_type amt = sizeof *p;
914 p = ((struct elf_i386_dyn_relocs *)
915 bfd_alloc (htab->elf.dynobj, amt));
916 if (p == NULL)
917 return false;
918 p->next = *head;
919 *head = p;
920 p->sec = sec;
921 p->count = 0;
922 p->pc_count = 0;
923 }
924
925 p->count += 1;
926 if (ELF32_R_TYPE (rel->r_info) == R_386_PC32)
927 p->pc_count += 1;
928 }
929 break;
930
931 /* This relocation describes the C++ object vtable hierarchy.
932 Reconstruct it for later use during GC. */
933 case R_386_GNU_VTINHERIT:
934 if (!_bfd_elf32_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
935 return false;
936 break;
937
938 /* This relocation describes which C++ vtable entries are actually
939 used. Record for later use during GC. */
940 case R_386_GNU_VTENTRY:
941 if (!_bfd_elf32_gc_record_vtentry (abfd, sec, h, rel->r_offset))
942 return false;
943 break;
944
945 default:
946 break;
947 }
948 }
949
950 return true;
951 }
952
953 /* Return the section that should be marked against GC for a given
954 relocation. */
955
956 static asection *
957 elf_i386_gc_mark_hook (abfd, info, rel, h, sym)
958 bfd *abfd;
959 struct bfd_link_info *info ATTRIBUTE_UNUSED;
960 Elf_Internal_Rela *rel;
961 struct elf_link_hash_entry *h;
962 Elf_Internal_Sym *sym;
963 {
964 if (h != NULL)
965 {
966 switch (ELF32_R_TYPE (rel->r_info))
967 {
968 case R_386_GNU_VTINHERIT:
969 case R_386_GNU_VTENTRY:
970 break;
971
972 default:
973 switch (h->root.type)
974 {
975 case bfd_link_hash_defined:
976 case bfd_link_hash_defweak:
977 return h->root.u.def.section;
978
979 case bfd_link_hash_common:
980 return h->root.u.c.p->section;
981
982 default:
983 break;
984 }
985 }
986 }
987 else
988 {
989 return bfd_section_from_elf_index (abfd, sym->st_shndx);
990 }
991
992 return NULL;
993 }
994
995 /* Update the got entry reference counts for the section being removed. */
996
997 static boolean
998 elf_i386_gc_sweep_hook (abfd, info, sec, relocs)
999 bfd *abfd;
1000 struct bfd_link_info *info;
1001 asection *sec;
1002 const Elf_Internal_Rela *relocs;
1003 {
1004 Elf_Internal_Shdr *symtab_hdr;
1005 struct elf_link_hash_entry **sym_hashes;
1006 bfd_signed_vma *local_got_refcounts;
1007 const Elf_Internal_Rela *rel, *relend;
1008 unsigned long r_symndx;
1009 struct elf_link_hash_entry *h;
1010
1011 elf_section_data (sec)->local_dynrel = NULL;
1012
1013 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1014 sym_hashes = elf_sym_hashes (abfd);
1015 local_got_refcounts = elf_local_got_refcounts (abfd);
1016
1017 relend = relocs + sec->reloc_count;
1018 for (rel = relocs; rel < relend; rel++)
1019 switch (ELF32_R_TYPE (rel->r_info))
1020 {
1021 case R_386_GOT32:
1022 case R_386_GOTOFF:
1023 case R_386_GOTPC:
1024 r_symndx = ELF32_R_SYM (rel->r_info);
1025 if (r_symndx >= symtab_hdr->sh_info)
1026 {
1027 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1028 if (h->got.refcount > 0)
1029 h->got.refcount -= 1;
1030 }
1031 else if (local_got_refcounts != NULL)
1032 {
1033 if (local_got_refcounts[r_symndx] > 0)
1034 local_got_refcounts[r_symndx] -= 1;
1035 }
1036 break;
1037
1038 case R_386_32:
1039 case R_386_PC32:
1040 r_symndx = ELF32_R_SYM (rel->r_info);
1041 if (r_symndx >= symtab_hdr->sh_info)
1042 {
1043 struct elf_i386_link_hash_entry *eh;
1044 struct elf_i386_dyn_relocs **pp;
1045 struct elf_i386_dyn_relocs *p;
1046
1047 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1048
1049 if (!info->shared && h->plt.refcount > 0)
1050 h->plt.refcount -= 1;
1051
1052 eh = (struct elf_i386_link_hash_entry *) h;
1053
1054 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1055 if (p->sec == sec)
1056 {
1057 if (ELF32_R_TYPE (rel->r_info) == R_386_PC32)
1058 p->pc_count -= 1;
1059 p->count -= 1;
1060 if (p->count == 0)
1061 *pp = p->next;
1062 break;
1063 }
1064 }
1065 break;
1066
1067 case R_386_PLT32:
1068 r_symndx = ELF32_R_SYM (rel->r_info);
1069 if (r_symndx >= symtab_hdr->sh_info)
1070 {
1071 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1072 if (h->plt.refcount > 0)
1073 h->plt.refcount -= 1;
1074 }
1075 break;
1076
1077 default:
1078 break;
1079 }
1080
1081 return true;
1082 }
1083
1084 /* Adjust a symbol defined by a dynamic object and referenced by a
1085 regular object. The current definition is in some section of the
1086 dynamic object, but we're not including those sections. We have to
1087 change the definition to something the rest of the link can
1088 understand. */
1089
1090 static boolean
1091 elf_i386_adjust_dynamic_symbol (info, h)
1092 struct bfd_link_info *info;
1093 struct elf_link_hash_entry *h;
1094 {
1095 struct elf_i386_link_hash_table *htab;
1096 struct elf_i386_link_hash_entry * eh;
1097 struct elf_i386_dyn_relocs *p;
1098 asection *s;
1099 unsigned int power_of_two;
1100
1101 /* If this is a function, put it in the procedure linkage table. We
1102 will fill in the contents of the procedure linkage table later,
1103 when we know the address of the .got section. */
1104 if (h->type == STT_FUNC
1105 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1106 {
1107 if (h->plt.refcount <= 0
1108 || (! info->shared
1109 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0
1110 && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) == 0
1111 && h->root.type != bfd_link_hash_undefweak
1112 && h->root.type != bfd_link_hash_undefined))
1113 {
1114 /* This case can occur if we saw a PLT32 reloc in an input
1115 file, but the symbol was never referred to by a dynamic
1116 object, or if all references were garbage collected. In
1117 such a case, we don't actually need to build a procedure
1118 linkage table, and we can just do a PC32 reloc instead. */
1119 h->plt.offset = (bfd_vma) -1;
1120 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1121 }
1122
1123 return true;
1124 }
1125 else
1126 /* It's possible that we incorrectly decided a .plt reloc was
1127 needed for an R_386_PC32 reloc to a non-function sym in
1128 check_relocs. We can't decide accurately between function and
1129 non-function syms in check-relocs; Objects loaded later in
1130 the link may change h->type. So fix it now. */
1131 h->plt.offset = (bfd_vma) -1;
1132
1133 /* If this is a weak symbol, and there is a real definition, the
1134 processor independent code will have arranged for us to see the
1135 real definition first, and we can just use the same value. */
1136 if (h->weakdef != NULL)
1137 {
1138 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1139 || h->weakdef->root.type == bfd_link_hash_defweak);
1140 h->root.u.def.section = h->weakdef->root.u.def.section;
1141 h->root.u.def.value = h->weakdef->root.u.def.value;
1142 return true;
1143 }
1144
1145 /* This is a reference to a symbol defined by a dynamic object which
1146 is not a function. */
1147
1148 /* If we are creating a shared library, we must presume that the
1149 only references to the symbol are via the global offset table.
1150 For such cases we need not do anything here; the relocations will
1151 be handled correctly by relocate_section. */
1152 if (info->shared)
1153 return true;
1154
1155 /* If there are no references to this symbol that do not use the
1156 GOT, we don't need to generate a copy reloc. */
1157 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1158 return true;
1159
1160 /* If -z nocopyreloc was given, we won't generate them either. */
1161 if (info->nocopyreloc)
1162 {
1163 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1164 return true;
1165 }
1166
1167 eh = (struct elf_i386_link_hash_entry *) h;
1168 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1169 {
1170 s = p->sec->output_section;
1171 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1172 break;
1173 }
1174
1175 /* If we didn't find any dynamic relocs in read-only sections, then
1176 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1177 if (p == NULL)
1178 {
1179 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1180 return true;
1181 }
1182
1183 /* We must allocate the symbol in our .dynbss section, which will
1184 become part of the .bss section of the executable. There will be
1185 an entry for this symbol in the .dynsym section. The dynamic
1186 object will contain position independent code, so all references
1187 from the dynamic object to this symbol will go through the global
1188 offset table. The dynamic linker will use the .dynsym entry to
1189 determine the address it must put in the global offset table, so
1190 both the dynamic object and the regular object will refer to the
1191 same memory location for the variable. */
1192
1193 htab = elf_i386_hash_table (info);
1194
1195 /* We must generate a R_386_COPY reloc to tell the dynamic linker to
1196 copy the initial value out of the dynamic object and into the
1197 runtime process image. */
1198 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1199 {
1200 htab->srelbss->_raw_size += sizeof (Elf32_External_Rel);
1201 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1202 }
1203
1204 /* We need to figure out the alignment required for this symbol. I
1205 have no idea how ELF linkers handle this. */
1206 power_of_two = bfd_log2 (h->size);
1207 if (power_of_two > 3)
1208 power_of_two = 3;
1209
1210 /* Apply the required alignment. */
1211 s = htab->sdynbss;
1212 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1213 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1214 {
1215 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1216 return false;
1217 }
1218
1219 /* Define the symbol as being at this point in the section. */
1220 h->root.u.def.section = s;
1221 h->root.u.def.value = s->_raw_size;
1222
1223 /* Increment the section size to make room for the symbol. */
1224 s->_raw_size += h->size;
1225
1226 return true;
1227 }
1228
1229 /* This is the condition under which elf_i386_finish_dynamic_symbol
1230 will be called from elflink.h. If elflink.h doesn't call our
1231 finish_dynamic_symbol routine, we'll need to do something about
1232 initializing any .plt and .got entries in elf_i386_relocate_section. */
1233 #define WILL_CALL_FINISH_DYNAMIC_SYMBOL(DYN, INFO, H) \
1234 ((DYN) \
1235 && ((INFO)->shared \
1236 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0) \
1237 && ((H)->dynindx != -1 \
1238 || ((H)->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0))
1239
1240 /* Allocate space in .plt, .got and associated reloc sections for
1241 dynamic relocs. */
1242
1243 static boolean
1244 allocate_dynrelocs (h, inf)
1245 struct elf_link_hash_entry *h;
1246 PTR inf;
1247 {
1248 struct bfd_link_info *info;
1249 struct elf_i386_link_hash_table *htab;
1250 struct elf_i386_link_hash_entry *eh;
1251 struct elf_i386_dyn_relocs *p;
1252
1253 if (h->root.type == bfd_link_hash_indirect)
1254 return true;
1255
1256 if (h->root.type == bfd_link_hash_warning)
1257 /* When warning symbols are created, they **replace** the "real"
1258 entry in the hash table, thus we never get to see the real
1259 symbol in a hash traversal. So look at it now. */
1260 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1261
1262 info = (struct bfd_link_info *) inf;
1263 htab = elf_i386_hash_table (info);
1264
1265 if (htab->elf.dynamic_sections_created
1266 && h->plt.refcount > 0)
1267 {
1268 /* Make sure this symbol is output as a dynamic symbol.
1269 Undefined weak syms won't yet be marked as dynamic. */
1270 if (h->dynindx == -1
1271 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1272 {
1273 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1274 return false;
1275 }
1276
1277 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, info, h))
1278 {
1279 asection *s = htab->splt;
1280
1281 /* If this is the first .plt entry, make room for the special
1282 first entry. */
1283 if (s->_raw_size == 0)
1284 s->_raw_size += PLT_ENTRY_SIZE;
1285
1286 h->plt.offset = s->_raw_size;
1287
1288 /* If this symbol is not defined in a regular file, and we are
1289 not generating a shared library, then set the symbol to this
1290 location in the .plt. This is required to make function
1291 pointers compare as equal between the normal executable and
1292 the shared library. */
1293 if (! info->shared
1294 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1295 {
1296 h->root.u.def.section = s;
1297 h->root.u.def.value = h->plt.offset;
1298 }
1299
1300 /* Make room for this entry. */
1301 s->_raw_size += PLT_ENTRY_SIZE;
1302
1303 /* We also need to make an entry in the .got.plt section, which
1304 will be placed in the .got section by the linker script. */
1305 htab->sgotplt->_raw_size += 4;
1306
1307 /* We also need to make an entry in the .rel.plt section. */
1308 htab->srelplt->_raw_size += sizeof (Elf32_External_Rel);
1309 }
1310 else
1311 {
1312 h->plt.offset = (bfd_vma) -1;
1313 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1314 }
1315 }
1316 else
1317 {
1318 h->plt.offset = (bfd_vma) -1;
1319 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1320 }
1321
1322 if (h->got.refcount > 0)
1323 {
1324 asection *s;
1325 boolean dyn;
1326
1327 /* Make sure this symbol is output as a dynamic symbol.
1328 Undefined weak syms won't yet be marked as dynamic. */
1329 if (h->dynindx == -1
1330 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1331 {
1332 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1333 return false;
1334 }
1335
1336 s = htab->sgot;
1337 h->got.offset = s->_raw_size;
1338 s->_raw_size += 4;
1339 dyn = htab->elf.dynamic_sections_created;
1340 if (WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h))
1341 htab->srelgot->_raw_size += sizeof (Elf32_External_Rel);
1342 }
1343 else
1344 h->got.offset = (bfd_vma) -1;
1345
1346 eh = (struct elf_i386_link_hash_entry *) h;
1347 if (eh->dyn_relocs == NULL)
1348 return true;
1349
1350 /* In the shared -Bsymbolic case, discard space allocated for
1351 dynamic pc-relative relocs against symbols which turn out to be
1352 defined in regular objects. For the normal shared case, discard
1353 space for pc-relative relocs that have become local due to symbol
1354 visibility changes. */
1355
1356 if (info->shared)
1357 {
1358 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0
1359 && ((h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) != 0
1360 || info->symbolic))
1361 {
1362 struct elf_i386_dyn_relocs **pp;
1363
1364 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1365 {
1366 p->count -= p->pc_count;
1367 p->pc_count = 0;
1368 if (p->count == 0)
1369 *pp = p->next;
1370 else
1371 pp = &p->next;
1372 }
1373 }
1374 }
1375 else
1376 {
1377 /* For the non-shared case, discard space for relocs against
1378 symbols which turn out to need copy relocs or are not
1379 dynamic. */
1380
1381 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1382 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1383 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1384 || (htab->elf.dynamic_sections_created
1385 && (h->root.type == bfd_link_hash_undefweak
1386 || h->root.type == bfd_link_hash_undefined))))
1387 {
1388 /* Make sure this symbol is output as a dynamic symbol.
1389 Undefined weak syms won't yet be marked as dynamic. */
1390 if (h->dynindx == -1
1391 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1392 {
1393 if (! bfd_elf32_link_record_dynamic_symbol (info, h))
1394 return false;
1395 }
1396
1397 /* If that succeeded, we know we'll be keeping all the
1398 relocs. */
1399 if (h->dynindx != -1)
1400 goto keep;
1401 }
1402
1403 eh->dyn_relocs = NULL;
1404
1405 keep: ;
1406 }
1407
1408 /* Finally, allocate space. */
1409 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1410 {
1411 asection *sreloc = elf_section_data (p->sec)->sreloc;
1412 sreloc->_raw_size += p->count * sizeof (Elf32_External_Rel);
1413 }
1414
1415 return true;
1416 }
1417
1418 /* Find any dynamic relocs that apply to read-only sections. */
1419
1420 static boolean
1421 readonly_dynrelocs (h, inf)
1422 struct elf_link_hash_entry *h;
1423 PTR inf;
1424 {
1425 struct elf_i386_link_hash_entry *eh;
1426 struct elf_i386_dyn_relocs *p;
1427
1428 if (h->root.type == bfd_link_hash_warning)
1429 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1430
1431 eh = (struct elf_i386_link_hash_entry *) h;
1432 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1433 {
1434 asection *s = p->sec->output_section;
1435
1436 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1437 {
1438 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1439
1440 info->flags |= DF_TEXTREL;
1441
1442 /* Not an error, just cut short the traversal. */
1443 return false;
1444 }
1445 }
1446 return true;
1447 }
1448
1449 /* Set the sizes of the dynamic sections. */
1450
1451 static boolean
1452 elf_i386_size_dynamic_sections (output_bfd, info)
1453 bfd *output_bfd ATTRIBUTE_UNUSED;
1454 struct bfd_link_info *info;
1455 {
1456 struct elf_i386_link_hash_table *htab;
1457 bfd *dynobj;
1458 asection *s;
1459 boolean relocs;
1460 bfd *ibfd;
1461
1462 htab = elf_i386_hash_table (info);
1463 dynobj = htab->elf.dynobj;
1464 if (dynobj == NULL)
1465 abort ();
1466
1467 if (htab->elf.dynamic_sections_created)
1468 {
1469 /* Set the contents of the .interp section to the interpreter. */
1470 if (! info->shared)
1471 {
1472 s = bfd_get_section_by_name (dynobj, ".interp");
1473 if (s == NULL)
1474 abort ();
1475 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1476 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1477 }
1478 }
1479
1480 /* Set up .got offsets for local syms, and space for local dynamic
1481 relocs. */
1482 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1483 {
1484 bfd_signed_vma *local_got;
1485 bfd_signed_vma *end_local_got;
1486 bfd_size_type locsymcount;
1487 Elf_Internal_Shdr *symtab_hdr;
1488 asection *srel;
1489
1490 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1491 continue;
1492
1493 for (s = ibfd->sections; s != NULL; s = s->next)
1494 {
1495 struct elf_i386_dyn_relocs *p;
1496
1497 for (p = *((struct elf_i386_dyn_relocs **)
1498 &elf_section_data (s)->local_dynrel);
1499 p != NULL;
1500 p = p->next)
1501 {
1502 if (!bfd_is_abs_section (p->sec)
1503 && bfd_is_abs_section (p->sec->output_section))
1504 {
1505 /* Input section has been discarded, either because
1506 it is a copy of a linkonce section or due to
1507 linker script /DISCARD/, so we'll be discarding
1508 the relocs too. */
1509 }
1510 else if (p->count != 0)
1511 {
1512 srel = elf_section_data (p->sec)->sreloc;
1513 srel->_raw_size += p->count * sizeof (Elf32_External_Rel);
1514 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1515 info->flags |= DF_TEXTREL;
1516 }
1517 }
1518 }
1519
1520 local_got = elf_local_got_refcounts (ibfd);
1521 if (!local_got)
1522 continue;
1523
1524 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1525 locsymcount = symtab_hdr->sh_info;
1526 end_local_got = local_got + locsymcount;
1527 s = htab->sgot;
1528 srel = htab->srelgot;
1529 for (; local_got < end_local_got; ++local_got)
1530 {
1531 if (*local_got > 0)
1532 {
1533 *local_got = s->_raw_size;
1534 s->_raw_size += 4;
1535 if (info->shared)
1536 srel->_raw_size += sizeof (Elf32_External_Rel);
1537 }
1538 else
1539 *local_got = (bfd_vma) -1;
1540 }
1541 }
1542
1543 /* Allocate global sym .plt and .got entries, and space for global
1544 sym dynamic relocs. */
1545 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1546
1547 /* We now have determined the sizes of the various dynamic sections.
1548 Allocate memory for them. */
1549 relocs = false;
1550 for (s = dynobj->sections; s != NULL; s = s->next)
1551 {
1552 if ((s->flags & SEC_LINKER_CREATED) == 0)
1553 continue;
1554
1555 if (s == htab->splt
1556 || s == htab->sgot
1557 || s == htab->sgotplt)
1558 {
1559 /* Strip this section if we don't need it; see the
1560 comment below. */
1561 }
1562 else if (strncmp (bfd_get_section_name (dynobj, s), ".rel", 4) == 0)
1563 {
1564 if (s->_raw_size != 0 && s != htab->srelplt)
1565 relocs = true;
1566
1567 /* We use the reloc_count field as a counter if we need
1568 to copy relocs into the output file. */
1569 s->reloc_count = 0;
1570 }
1571 else
1572 {
1573 /* It's not one of our sections, so don't allocate space. */
1574 continue;
1575 }
1576
1577 if (s->_raw_size == 0)
1578 {
1579 /* If we don't need this section, strip it from the
1580 output file. This is mostly to handle .rel.bss and
1581 .rel.plt. We must create both sections in
1582 create_dynamic_sections, because they must be created
1583 before the linker maps input sections to output
1584 sections. The linker does that before
1585 adjust_dynamic_symbol is called, and it is that
1586 function which decides whether anything needs to go
1587 into these sections. */
1588
1589 _bfd_strip_section_from_output (info, s);
1590 continue;
1591 }
1592
1593 /* Allocate memory for the section contents. We use bfd_zalloc
1594 here in case unused entries are not reclaimed before the
1595 section's contents are written out. This should not happen,
1596 but this way if it does, we get a R_386_NONE reloc instead
1597 of garbage. */
1598 s->contents = (bfd_byte *) bfd_zalloc (dynobj, s->_raw_size);
1599 if (s->contents == NULL)
1600 return false;
1601 }
1602
1603 if (htab->elf.dynamic_sections_created)
1604 {
1605 /* Add some entries to the .dynamic section. We fill in the
1606 values later, in elf_i386_finish_dynamic_sections, but we
1607 must add the entries now so that we get the correct size for
1608 the .dynamic section. The DT_DEBUG entry is filled in by the
1609 dynamic linker and used by the debugger. */
1610 #define add_dynamic_entry(TAG, VAL) \
1611 bfd_elf32_add_dynamic_entry (info, (bfd_vma) (TAG), (bfd_vma) (VAL))
1612
1613 if (! info->shared)
1614 {
1615 if (!add_dynamic_entry (DT_DEBUG, 0))
1616 return false;
1617 }
1618
1619 if (htab->splt->_raw_size != 0)
1620 {
1621 if (!add_dynamic_entry (DT_PLTGOT, 0)
1622 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1623 || !add_dynamic_entry (DT_PLTREL, DT_REL)
1624 || !add_dynamic_entry (DT_JMPREL, 0))
1625 return false;
1626 }
1627
1628 if (relocs)
1629 {
1630 if (!add_dynamic_entry (DT_REL, 0)
1631 || !add_dynamic_entry (DT_RELSZ, 0)
1632 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel)))
1633 return false;
1634
1635 /* If any dynamic relocs apply to a read-only section,
1636 then we need a DT_TEXTREL entry. */
1637 if ((info->flags & DF_TEXTREL) == 0)
1638 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1639 (PTR) info);
1640
1641 if ((info->flags & DF_TEXTREL) != 0)
1642 {
1643 if (!add_dynamic_entry (DT_TEXTREL, 0))
1644 return false;
1645 }
1646 }
1647 }
1648 #undef add_dynamic_entry
1649
1650 return true;
1651 }
1652
1653 /* Set the correct type for an x86 ELF section. We do this by the
1654 section name, which is a hack, but ought to work. */
1655
1656 static boolean
1657 elf_i386_fake_sections (abfd, hdr, sec)
1658 bfd *abfd ATTRIBUTE_UNUSED;
1659 Elf32_Internal_Shdr *hdr;
1660 asection *sec;
1661 {
1662 register const char *name;
1663
1664 name = bfd_get_section_name (abfd, sec);
1665
1666 /* This is an ugly, but unfortunately necessary hack that is
1667 needed when producing EFI binaries on x86. It tells
1668 elf.c:elf_fake_sections() not to consider ".reloc" as a section
1669 containing ELF relocation info. We need this hack in order to
1670 be able to generate ELF binaries that can be translated into
1671 EFI applications (which are essentially COFF objects). Those
1672 files contain a COFF ".reloc" section inside an ELFNN object,
1673 which would normally cause BFD to segfault because it would
1674 attempt to interpret this section as containing relocation
1675 entries for section "oc". With this hack enabled, ".reloc"
1676 will be treated as a normal data section, which will avoid the
1677 segfault. However, you won't be able to create an ELFNN binary
1678 with a section named "oc" that needs relocations, but that's
1679 the kind of ugly side-effects you get when detecting section
1680 types based on their names... In practice, this limitation is
1681 unlikely to bite. */
1682 if (strcmp (name, ".reloc") == 0)
1683 hdr->sh_type = SHT_PROGBITS;
1684
1685 return true;
1686 }
1687
1688 /* Relocate an i386 ELF section. */
1689
1690 static boolean
1691 elf_i386_relocate_section (output_bfd, info, input_bfd, input_section,
1692 contents, relocs, local_syms, local_sections)
1693 bfd *output_bfd;
1694 struct bfd_link_info *info;
1695 bfd *input_bfd;
1696 asection *input_section;
1697 bfd_byte *contents;
1698 Elf_Internal_Rela *relocs;
1699 Elf_Internal_Sym *local_syms;
1700 asection **local_sections;
1701 {
1702 struct elf_i386_link_hash_table *htab;
1703 Elf_Internal_Shdr *symtab_hdr;
1704 struct elf_link_hash_entry **sym_hashes;
1705 bfd_vma *local_got_offsets;
1706 Elf_Internal_Rela *rel;
1707 Elf_Internal_Rela *relend;
1708
1709 htab = elf_i386_hash_table (info);
1710 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
1711 sym_hashes = elf_sym_hashes (input_bfd);
1712 local_got_offsets = elf_local_got_offsets (input_bfd);
1713
1714 rel = relocs;
1715 relend = relocs + input_section->reloc_count;
1716 for (; rel < relend; rel++)
1717 {
1718 int r_type;
1719 reloc_howto_type *howto;
1720 unsigned long r_symndx;
1721 struct elf_link_hash_entry *h;
1722 Elf_Internal_Sym *sym;
1723 asection *sec;
1724 bfd_vma off;
1725 bfd_vma relocation;
1726 boolean unresolved_reloc;
1727 boolean overflow;
1728 bfd_reloc_status_type r;
1729 unsigned int indx;
1730
1731 r_type = ELF32_R_TYPE (rel->r_info);
1732 if (r_type == (int) R_386_GNU_VTINHERIT
1733 || r_type == (int) R_386_GNU_VTENTRY)
1734 continue;
1735
1736 if ((indx = (unsigned) r_type) >= R_386_standard
1737 && ((indx = (unsigned) r_type - R_386_ext_offset) - R_386_standard
1738 >= R_386_ext - R_386_standard))
1739 {
1740 bfd_set_error (bfd_error_bad_value);
1741 return false;
1742 }
1743 howto = elf_howto_table + indx;
1744
1745 r_symndx = ELF32_R_SYM (rel->r_info);
1746
1747 if (info->relocateable)
1748 {
1749 bfd_vma val;
1750 bfd_vma addend;
1751 bfd_byte *where;
1752
1753 /* This is a relocatable link. We don't have to change
1754 anything, unless the reloc is against a section symbol,
1755 in which case we have to adjust according to where the
1756 section symbol winds up in the output section. */
1757 if (r_symndx >= symtab_hdr->sh_info)
1758 continue;
1759
1760 sym = local_syms + r_symndx;
1761 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
1762 continue;
1763
1764 sec = local_sections[r_symndx];
1765 val = sec->output_offset;
1766 if (val == 0)
1767 continue;
1768
1769 where = contents + rel->r_offset;
1770 switch (howto->size)
1771 {
1772 case 0:
1773 addend = bfd_get_8 (input_bfd, where);
1774 if (howto->pc_relative)
1775 addend = (addend ^ 0x80) - 0x80;
1776 val += addend;
1777 bfd_put_8 (input_bfd, val, where);
1778 if (howto->pc_relative)
1779 val += 0x80;
1780 if (val > 0xff)
1781 {
1782 h = NULL;
1783 r = bfd_reloc_overflow;
1784 goto overflow_error;
1785 }
1786 break;
1787 case 1:
1788 addend = bfd_get_16 (input_bfd, where);
1789 if (howto->pc_relative)
1790 addend = (addend ^ 0x8000) - 0x8000;
1791 val += addend;
1792 bfd_put_16 (input_bfd, val, where);
1793 if (howto->pc_relative)
1794 val += 0x8000;
1795 if (output_bfd->arch_info->mach != bfd_mach_i386_i8086
1796 && val > 0xffff)
1797 {
1798 h = NULL;
1799 r = bfd_reloc_overflow;
1800 goto overflow_error;
1801 }
1802 break;
1803 case 2:
1804 val += bfd_get_32 (input_bfd, where);
1805 bfd_put_32 (input_bfd, val, where);
1806 break;
1807 default:
1808 abort ();
1809 }
1810 continue;
1811 }
1812
1813 /* This is a final link. */
1814 h = NULL;
1815 sym = NULL;
1816 sec = NULL;
1817 unresolved_reloc = false;
1818 overflow = false;
1819 if (r_symndx < symtab_hdr->sh_info)
1820 {
1821 sym = local_syms + r_symndx;
1822 sec = local_sections[r_symndx];
1823 relocation = (sec->output_section->vma
1824 + sec->output_offset
1825 + sym->st_value);
1826 if ((sec->flags & SEC_MERGE)
1827 && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
1828 {
1829 asection *msec;
1830 bfd_vma addend;
1831 bfd_byte *where = contents + rel->r_offset;
1832
1833 switch (howto->size)
1834 {
1835 case 0:
1836 addend = bfd_get_8 (input_bfd, where);
1837 if (howto->pc_relative)
1838 {
1839 addend = (addend ^ 0x80) - 0x80;
1840 addend += 1;
1841 }
1842 break;
1843 case 1:
1844 addend = bfd_get_16 (input_bfd, where);
1845 if (howto->pc_relative)
1846 {
1847 addend = (addend ^ 0x8000) - 0x8000;
1848 addend += 2;
1849 }
1850 break;
1851 case 2:
1852 addend = bfd_get_32 (input_bfd, where);
1853 if (howto->pc_relative)
1854 {
1855 addend = (addend ^ 0x80000000) - 0x80000000;
1856 addend += 4;
1857 }
1858 break;
1859 default:
1860 abort ();
1861 }
1862
1863 msec = sec;
1864 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
1865 addend -= relocation;
1866 addend += msec->output_section->vma + msec->output_offset;
1867
1868 switch (howto->size)
1869 {
1870 case 0:
1871 if (howto->pc_relative)
1872 addend -= 1;
1873 bfd_put_8 (input_bfd, addend, where);
1874 if (howto->pc_relative)
1875 addend += 0x80;
1876 overflow = addend > 0xff;
1877 break;
1878 case 1:
1879 if (howto->pc_relative)
1880 addend -= 2;
1881 bfd_put_16 (input_bfd, addend, where);
1882 if (howto->pc_relative)
1883 addend += 0x8000;
1884 if (output_bfd->arch_info->mach != bfd_mach_i386_i8086)
1885 overflow = addend > 0xffff;
1886 break;
1887 case 2:
1888 if (howto->pc_relative)
1889 addend -= 4;
1890 bfd_put_32 (input_bfd, addend, where);
1891 break;
1892 }
1893 }
1894 }
1895 else
1896 {
1897 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1898 while (h->root.type == bfd_link_hash_indirect
1899 || h->root.type == bfd_link_hash_warning)
1900 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1901
1902 relocation = 0;
1903 if (h->root.type == bfd_link_hash_defined
1904 || h->root.type == bfd_link_hash_defweak)
1905 {
1906 sec = h->root.u.def.section;
1907 if (sec->output_section == NULL)
1908 /* Set a flag that will be cleared later if we find a
1909 relocation value for this symbol. output_section
1910 is typically NULL for symbols satisfied by a shared
1911 library. */
1912 unresolved_reloc = true;
1913 else
1914 relocation = (h->root.u.def.value
1915 + sec->output_section->vma
1916 + sec->output_offset);
1917 }
1918 else if (h->root.type == bfd_link_hash_undefweak)
1919 ;
1920 else if (info->shared
1921 && (!info->symbolic || info->allow_shlib_undefined)
1922 && !info->no_undefined
1923 && ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
1924 ;
1925 else
1926 {
1927 if (! ((*info->callbacks->undefined_symbol)
1928 (info, h->root.root.string, input_bfd,
1929 input_section, rel->r_offset,
1930 (!info->shared || info->no_undefined
1931 || ELF_ST_VISIBILITY (h->other)))))
1932 return false;
1933 }
1934 }
1935
1936 switch (r_type)
1937 {
1938 case R_386_GOT32:
1939 /* Relocation is to the entry for this symbol in the global
1940 offset table. */
1941 if (htab->sgot == NULL)
1942 abort ();
1943
1944 if (h != NULL)
1945 {
1946 boolean dyn;
1947
1948 off = h->got.offset;
1949 dyn = htab->elf.dynamic_sections_created;
1950 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info, h)
1951 || (info->shared
1952 && (info->symbolic
1953 || h->dynindx == -1
1954 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
1955 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR)))
1956 {
1957 /* This is actually a static link, or it is a
1958 -Bsymbolic link and the symbol is defined
1959 locally, or the symbol was forced to be local
1960 because of a version file. We must initialize
1961 this entry in the global offset table. Since the
1962 offset must always be a multiple of 4, we use the
1963 least significant bit to record whether we have
1964 initialized it already.
1965
1966 When doing a dynamic link, we create a .rel.got
1967 relocation entry to initialize the value. This
1968 is done in the finish_dynamic_symbol routine. */
1969 if ((off & 1) != 0)
1970 off &= ~1;
1971 else
1972 {
1973 bfd_put_32 (output_bfd, relocation,
1974 htab->sgot->contents + off);
1975 h->got.offset |= 1;
1976 }
1977 }
1978 else
1979 unresolved_reloc = false;
1980 }
1981 else
1982 {
1983 if (local_got_offsets == NULL)
1984 abort ();
1985
1986 off = local_got_offsets[r_symndx];
1987
1988 /* The offset must always be a multiple of 4. We use
1989 the least significant bit to record whether we have
1990 already generated the necessary reloc. */
1991 if ((off & 1) != 0)
1992 off &= ~1;
1993 else
1994 {
1995 bfd_put_32 (output_bfd, relocation,
1996 htab->sgot->contents + off);
1997
1998 if (info->shared)
1999 {
2000 asection *srelgot;
2001 Elf_Internal_Rel outrel;
2002 Elf32_External_Rel *loc;
2003
2004 srelgot = htab->srelgot;
2005 if (srelgot == NULL)
2006 abort ();
2007
2008 outrel.r_offset = (htab->sgot->output_section->vma
2009 + htab->sgot->output_offset
2010 + off);
2011 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2012 loc = (Elf32_External_Rel *) srelgot->contents;
2013 loc += srelgot->reloc_count++;
2014 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2015 }
2016
2017 local_got_offsets[r_symndx] |= 1;
2018 }
2019 }
2020
2021 if (off >= (bfd_vma) -2)
2022 abort ();
2023
2024 relocation = htab->sgot->output_offset + off;
2025 break;
2026
2027 case R_386_GOTOFF:
2028 /* Relocation is relative to the start of the global offset
2029 table. */
2030
2031 /* Note that sgot->output_offset is not involved in this
2032 calculation. We always want the start of .got. If we
2033 defined _GLOBAL_OFFSET_TABLE in a different way, as is
2034 permitted by the ABI, we might have to change this
2035 calculation. */
2036 relocation -= htab->sgot->output_section->vma;
2037 break;
2038
2039 case R_386_GOTPC:
2040 /* Use global offset table as symbol value. */
2041 relocation = htab->sgot->output_section->vma;
2042 unresolved_reloc = false;
2043 break;
2044
2045 case R_386_PLT32:
2046 /* Relocation is to the entry for this symbol in the
2047 procedure linkage table. */
2048
2049 /* Resolve a PLT32 reloc against a local symbol directly,
2050 without using the procedure linkage table. */
2051 if (h == NULL)
2052 break;
2053
2054 if (h->plt.offset == (bfd_vma) -1
2055 || htab->splt == NULL)
2056 {
2057 /* We didn't make a PLT entry for this symbol. This
2058 happens when statically linking PIC code, or when
2059 using -Bsymbolic. */
2060 break;
2061 }
2062
2063 relocation = (htab->splt->output_section->vma
2064 + htab->splt->output_offset
2065 + h->plt.offset);
2066 unresolved_reloc = false;
2067 break;
2068
2069 case R_386_32:
2070 case R_386_PC32:
2071 /* r_symndx will be zero only for relocs against symbols
2072 from removed linkonce sections, or sections discarded by
2073 a linker script. */
2074 if (r_symndx == 0
2075 || (input_section->flags & SEC_ALLOC) == 0)
2076 break;
2077
2078 if ((info->shared
2079 && (r_type != R_386_PC32
2080 || (h != NULL
2081 && h->dynindx != -1
2082 && (! info->symbolic
2083 || (h->elf_link_hash_flags
2084 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
2085 || (!info->shared
2086 && h != NULL
2087 && h->dynindx != -1
2088 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
2089 && (((h->elf_link_hash_flags
2090 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2091 && (h->elf_link_hash_flags
2092 & ELF_LINK_HASH_DEF_REGULAR) == 0)
2093 || h->root.type == bfd_link_hash_undefweak
2094 || h->root.type == bfd_link_hash_undefined)))
2095 {
2096 Elf_Internal_Rel outrel;
2097 boolean skip, relocate;
2098 asection *sreloc;
2099 Elf32_External_Rel *loc;
2100
2101 /* When generating a shared object, these relocations
2102 are copied into the output file to be resolved at run
2103 time. */
2104
2105 skip = false;
2106 relocate = false;
2107
2108 outrel.r_offset =
2109 _bfd_elf_section_offset (output_bfd, info, input_section,
2110 rel->r_offset);
2111 if (outrel.r_offset == (bfd_vma) -1)
2112 skip = true;
2113 else if (outrel.r_offset == (bfd_vma) -2)
2114 skip = true, relocate = true;
2115 outrel.r_offset += (input_section->output_section->vma
2116 + input_section->output_offset);
2117
2118 if (skip)
2119 memset (&outrel, 0, sizeof outrel);
2120 else if (h != NULL
2121 && h->dynindx != -1
2122 && (r_type == R_386_PC32
2123 || !info->shared
2124 || !info->symbolic
2125 || (h->elf_link_hash_flags
2126 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2127 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
2128 else
2129 {
2130 /* This symbol is local, or marked to become local. */
2131 relocate = true;
2132 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2133 }
2134
2135 sreloc = elf_section_data (input_section)->sreloc;
2136 if (sreloc == NULL)
2137 abort ();
2138
2139 loc = (Elf32_External_Rel *) sreloc->contents;
2140 loc += sreloc->reloc_count++;
2141 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2142
2143 /* If this reloc is against an external symbol, we do
2144 not want to fiddle with the addend. Otherwise, we
2145 need to include the symbol value so that it becomes
2146 an addend for the dynamic reloc. */
2147 if (! relocate)
2148 continue;
2149 }
2150 break;
2151
2152 default:
2153 break;
2154 }
2155
2156 /* FIXME: Why do we allow debugging sections to escape this error?
2157 More importantly, why do we not emit dynamic relocs for
2158 R_386_32 above in debugging sections (which are ! SEC_ALLOC)?
2159 If we had emitted the dynamic reloc, we could remove the
2160 fudge here. */
2161 if (unresolved_reloc
2162 && !(info->shared
2163 && (input_section->flags & SEC_DEBUGGING) != 0
2164 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2165 (*_bfd_error_handler)
2166 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2167 bfd_archive_filename (input_bfd),
2168 bfd_get_section_name (input_bfd, input_section),
2169 (long) rel->r_offset,
2170 h->root.root.string);
2171
2172 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2173 contents, rel->r_offset,
2174 relocation, (bfd_vma) 0);
2175 if (overflow && r == bfd_reloc_ok)
2176 r = bfd_reloc_overflow;
2177
2178 overflow_error:
2179 if (r != bfd_reloc_ok)
2180 {
2181 const char *name;
2182
2183 if (h != NULL)
2184 name = h->root.root.string;
2185 else
2186 {
2187 name = bfd_elf_string_from_elf_section (input_bfd,
2188 symtab_hdr->sh_link,
2189 sym->st_name);
2190 if (name == NULL)
2191 return false;
2192 if (*name == '\0')
2193 name = bfd_section_name (input_bfd, sec);
2194 }
2195
2196 if (r == bfd_reloc_overflow)
2197 {
2198 if (! ((*info->callbacks->reloc_overflow)
2199 (info, name, howto->name, (bfd_vma) 0,
2200 input_bfd, input_section, rel->r_offset)))
2201 return false;
2202 }
2203 else
2204 {
2205 (*_bfd_error_handler)
2206 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2207 bfd_archive_filename (input_bfd),
2208 bfd_get_section_name (input_bfd, input_section),
2209 (long) rel->r_offset, name, (int) r);
2210 return false;
2211 }
2212 }
2213 }
2214
2215 return true;
2216 }
2217
2218 /* Finish up dynamic symbol handling. We set the contents of various
2219 dynamic sections here. */
2220
2221 static boolean
2222 elf_i386_finish_dynamic_symbol (output_bfd, info, h, sym)
2223 bfd *output_bfd;
2224 struct bfd_link_info *info;
2225 struct elf_link_hash_entry *h;
2226 Elf_Internal_Sym *sym;
2227 {
2228 struct elf_i386_link_hash_table *htab;
2229
2230 htab = elf_i386_hash_table (info);
2231
2232 if (h->plt.offset != (bfd_vma) -1)
2233 {
2234 bfd_vma plt_index;
2235 bfd_vma got_offset;
2236 Elf_Internal_Rel rel;
2237 Elf32_External_Rel *loc;
2238
2239 /* This symbol has an entry in the procedure linkage table. Set
2240 it up. */
2241
2242 if (h->dynindx == -1
2243 || htab->splt == NULL
2244 || htab->sgotplt == NULL
2245 || htab->srelplt == NULL)
2246 abort ();
2247
2248 /* Get the index in the procedure linkage table which
2249 corresponds to this symbol. This is the index of this symbol
2250 in all the symbols for which we are making plt entries. The
2251 first entry in the procedure linkage table is reserved. */
2252 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2253
2254 /* Get the offset into the .got table of the entry that
2255 corresponds to this function. Each .got entry is 4 bytes.
2256 The first three are reserved. */
2257 got_offset = (plt_index + 3) * 4;
2258
2259 /* Fill in the entry in the procedure linkage table. */
2260 if (! info->shared)
2261 {
2262 memcpy (htab->splt->contents + h->plt.offset, elf_i386_plt_entry,
2263 PLT_ENTRY_SIZE);
2264 bfd_put_32 (output_bfd,
2265 (htab->sgotplt->output_section->vma
2266 + htab->sgotplt->output_offset
2267 + got_offset),
2268 htab->splt->contents + h->plt.offset + 2);
2269 }
2270 else
2271 {
2272 memcpy (htab->splt->contents + h->plt.offset, elf_i386_pic_plt_entry,
2273 PLT_ENTRY_SIZE);
2274 bfd_put_32 (output_bfd, got_offset,
2275 htab->splt->contents + h->plt.offset + 2);
2276 }
2277
2278 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
2279 htab->splt->contents + h->plt.offset + 7);
2280 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
2281 htab->splt->contents + h->plt.offset + 12);
2282
2283 /* Fill in the entry in the global offset table. */
2284 bfd_put_32 (output_bfd,
2285 (htab->splt->output_section->vma
2286 + htab->splt->output_offset
2287 + h->plt.offset
2288 + 6),
2289 htab->sgotplt->contents + got_offset);
2290
2291 /* Fill in the entry in the .rel.plt section. */
2292 rel.r_offset = (htab->sgotplt->output_section->vma
2293 + htab->sgotplt->output_offset
2294 + got_offset);
2295 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
2296 loc = (Elf32_External_Rel *) htab->srelplt->contents + plt_index;
2297 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
2298
2299 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
2300 {
2301 /* Mark the symbol as undefined, rather than as defined in
2302 the .plt section. Leave the value alone. This is a clue
2303 for the dynamic linker, to make function pointer
2304 comparisons work between an application and shared
2305 library. */
2306 sym->st_shndx = SHN_UNDEF;
2307 }
2308 }
2309
2310 if (h->got.offset != (bfd_vma) -1)
2311 {
2312 Elf_Internal_Rel rel;
2313 Elf32_External_Rel *loc;
2314
2315 /* This symbol has an entry in the global offset table. Set it
2316 up. */
2317
2318 if (htab->sgot == NULL || htab->srelgot == NULL)
2319 abort ();
2320
2321 rel.r_offset = (htab->sgot->output_section->vma
2322 + htab->sgot->output_offset
2323 + (h->got.offset & ~(bfd_vma) 1));
2324
2325 /* If this is a static link, or it is a -Bsymbolic link and the
2326 symbol is defined locally or was forced to be local because
2327 of a version file, we just want to emit a RELATIVE reloc.
2328 The entry in the global offset table will already have been
2329 initialized in the relocate_section function. */
2330 if (info->shared
2331 && (info->symbolic
2332 || h->dynindx == -1
2333 || (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL))
2334 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR))
2335 {
2336 BFD_ASSERT((h->got.offset & 1) != 0);
2337 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2338 }
2339 else
2340 {
2341 BFD_ASSERT((h->got.offset & 1) == 0);
2342 bfd_put_32 (output_bfd, (bfd_vma) 0,
2343 htab->sgot->contents + h->got.offset);
2344 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
2345 }
2346
2347 loc = (Elf32_External_Rel *) htab->srelgot->contents;
2348 loc += htab->srelgot->reloc_count++;
2349 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
2350 }
2351
2352 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
2353 {
2354 Elf_Internal_Rel rel;
2355 Elf32_External_Rel *loc;
2356
2357 /* This symbol needs a copy reloc. Set it up. */
2358
2359 if (h->dynindx == -1
2360 || (h->root.type != bfd_link_hash_defined
2361 && h->root.type != bfd_link_hash_defweak)
2362 || htab->srelbss == NULL)
2363 abort ();
2364
2365 rel.r_offset = (h->root.u.def.value
2366 + h->root.u.def.section->output_section->vma
2367 + h->root.u.def.section->output_offset);
2368 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
2369 loc = (Elf32_External_Rel *) htab->srelbss->contents;
2370 loc += htab->srelbss->reloc_count++;
2371 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
2372 }
2373
2374 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
2375 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
2376 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
2377 sym->st_shndx = SHN_ABS;
2378
2379 return true;
2380 }
2381
2382 /* Used to decide how to sort relocs in an optimal manner for the
2383 dynamic linker, before writing them out. */
2384
2385 static enum elf_reloc_type_class
2386 elf_i386_reloc_type_class (rela)
2387 const Elf_Internal_Rela *rela;
2388 {
2389 switch ((int) ELF32_R_TYPE (rela->r_info))
2390 {
2391 case R_386_RELATIVE:
2392 return reloc_class_relative;
2393 case R_386_JUMP_SLOT:
2394 return reloc_class_plt;
2395 case R_386_COPY:
2396 return reloc_class_copy;
2397 default:
2398 return reloc_class_normal;
2399 }
2400 }
2401
2402 /* Finish up the dynamic sections. */
2403
2404 static boolean
2405 elf_i386_finish_dynamic_sections (output_bfd, info)
2406 bfd *output_bfd;
2407 struct bfd_link_info *info;
2408 {
2409 struct elf_i386_link_hash_table *htab;
2410 bfd *dynobj;
2411 asection *sdyn;
2412
2413 htab = elf_i386_hash_table (info);
2414 dynobj = htab->elf.dynobj;
2415 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2416
2417 if (htab->elf.dynamic_sections_created)
2418 {
2419 Elf32_External_Dyn *dyncon, *dynconend;
2420
2421 if (sdyn == NULL || htab->sgot == NULL)
2422 abort ();
2423
2424 dyncon = (Elf32_External_Dyn *) sdyn->contents;
2425 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
2426 for (; dyncon < dynconend; dyncon++)
2427 {
2428 Elf_Internal_Dyn dyn;
2429 asection *s;
2430
2431 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
2432
2433 switch (dyn.d_tag)
2434 {
2435 default:
2436 continue;
2437
2438 case DT_PLTGOT:
2439 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
2440 break;
2441
2442 case DT_JMPREL:
2443 dyn.d_un.d_ptr = htab->srelplt->output_section->vma;
2444 break;
2445
2446 case DT_PLTRELSZ:
2447 s = htab->srelplt->output_section;
2448 if (s->_cooked_size != 0)
2449 dyn.d_un.d_val = s->_cooked_size;
2450 else
2451 dyn.d_un.d_val = s->_raw_size;
2452 break;
2453
2454 case DT_RELSZ:
2455 /* My reading of the SVR4 ABI indicates that the
2456 procedure linkage table relocs (DT_JMPREL) should be
2457 included in the overall relocs (DT_REL). This is
2458 what Solaris does. However, UnixWare can not handle
2459 that case. Therefore, we override the DT_RELSZ entry
2460 here to make it not include the JMPREL relocs. Since
2461 the linker script arranges for .rel.plt to follow all
2462 other relocation sections, we don't have to worry
2463 about changing the DT_REL entry. */
2464 if (htab->srelplt != NULL)
2465 {
2466 s = htab->srelplt->output_section;
2467 if (s->_cooked_size != 0)
2468 dyn.d_un.d_val -= s->_cooked_size;
2469 else
2470 dyn.d_un.d_val -= s->_raw_size;
2471 }
2472 break;
2473 }
2474
2475 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
2476 }
2477
2478 /* Fill in the first entry in the procedure linkage table. */
2479 if (htab->splt && htab->splt->_raw_size > 0)
2480 {
2481 if (info->shared)
2482 memcpy (htab->splt->contents,
2483 elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
2484 else
2485 {
2486 memcpy (htab->splt->contents,
2487 elf_i386_plt0_entry, PLT_ENTRY_SIZE);
2488 bfd_put_32 (output_bfd,
2489 (htab->sgotplt->output_section->vma
2490 + htab->sgotplt->output_offset
2491 + 4),
2492 htab->splt->contents + 2);
2493 bfd_put_32 (output_bfd,
2494 (htab->sgotplt->output_section->vma
2495 + htab->sgotplt->output_offset
2496 + 8),
2497 htab->splt->contents + 8);
2498 }
2499
2500 /* UnixWare sets the entsize of .plt to 4, although that doesn't
2501 really seem like the right value. */
2502 elf_section_data (htab->splt->output_section)
2503 ->this_hdr.sh_entsize = 4;
2504 }
2505 }
2506
2507 if (htab->sgotplt)
2508 {
2509 /* Fill in the first three entries in the global offset table. */
2510 if (htab->sgotplt->_raw_size > 0)
2511 {
2512 bfd_put_32 (output_bfd,
2513 (sdyn == NULL ? (bfd_vma) 0
2514 : sdyn->output_section->vma + sdyn->output_offset),
2515 htab->sgotplt->contents);
2516 bfd_put_32 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 4);
2517 bfd_put_32 (output_bfd, (bfd_vma) 0, htab->sgotplt->contents + 8);
2518 }
2519
2520 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4;
2521 }
2522 return true;
2523 }
2524
2525 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
2526 #define TARGET_LITTLE_NAME "elf32-i386"
2527 #define ELF_ARCH bfd_arch_i386
2528 #define ELF_MACHINE_CODE EM_386
2529 #define ELF_MAXPAGESIZE 0x1000
2530
2531 #define elf_backend_can_gc_sections 1
2532 #define elf_backend_can_refcount 1
2533 #define elf_backend_want_got_plt 1
2534 #define elf_backend_plt_readonly 1
2535 #define elf_backend_want_plt_sym 0
2536 #define elf_backend_got_header_size 12
2537 #define elf_backend_plt_header_size PLT_ENTRY_SIZE
2538
2539 #define elf_info_to_howto elf_i386_info_to_howto
2540 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
2541
2542 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
2543 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
2544 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
2545
2546 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol
2547 #define elf_backend_check_relocs elf_i386_check_relocs
2548 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol
2549 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections
2550 #define elf_backend_fake_sections elf_i386_fake_sections
2551 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections
2552 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol
2553 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
2554 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
2555 #define elf_backend_grok_prstatus elf_i386_grok_prstatus
2556 #define elf_backend_grok_psinfo elf_i386_grok_psinfo
2557 #define elf_backend_reloc_type_class elf_i386_reloc_type_class
2558 #define elf_backend_relocate_section elf_i386_relocate_section
2559 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections
2560
2561 #include "elf32-target.h"