| 1 | /* ELF linker support. |
| 2 | Copyright 1995 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of BFD, the Binary File Descriptor library. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | /* ELF linker code. */ |
| 20 | |
| 21 | static boolean elf_link_add_object_symbols |
| 22 | PARAMS ((bfd *, struct bfd_link_info *)); |
| 23 | static boolean elf_link_add_archive_symbols |
| 24 | PARAMS ((bfd *, struct bfd_link_info *)); |
| 25 | static Elf_Internal_Rela *elf_link_read_relocs |
| 26 | PARAMS ((bfd *, asection *, PTR, Elf_Internal_Rela *, boolean)); |
| 27 | static boolean elf_export_symbol |
| 28 | PARAMS ((struct elf_link_hash_entry *, PTR)); |
| 29 | static boolean elf_adjust_dynamic_symbol |
| 30 | PARAMS ((struct elf_link_hash_entry *, PTR)); |
| 31 | |
| 32 | /* This struct is used to pass information to routines called via |
| 33 | elf_link_hash_traverse which must return failure. */ |
| 34 | |
| 35 | struct elf_info_failed |
| 36 | { |
| 37 | boolean failed; |
| 38 | struct bfd_link_info *info; |
| 39 | }; |
| 40 | |
| 41 | /* Given an ELF BFD, add symbols to the global hash table as |
| 42 | appropriate. */ |
| 43 | |
| 44 | boolean |
| 45 | elf_bfd_link_add_symbols (abfd, info) |
| 46 | bfd *abfd; |
| 47 | struct bfd_link_info *info; |
| 48 | { |
| 49 | switch (bfd_get_format (abfd)) |
| 50 | { |
| 51 | case bfd_object: |
| 52 | return elf_link_add_object_symbols (abfd, info); |
| 53 | case bfd_archive: |
| 54 | return elf_link_add_archive_symbols (abfd, info); |
| 55 | default: |
| 56 | bfd_set_error (bfd_error_wrong_format); |
| 57 | return false; |
| 58 | } |
| 59 | } |
| 60 | |
| 61 | /* Add symbols from an ELF archive file to the linker hash table. We |
| 62 | don't use _bfd_generic_link_add_archive_symbols because of a |
| 63 | problem which arises on UnixWare. The UnixWare libc.so is an |
| 64 | archive which includes an entry libc.so.1 which defines a bunch of |
| 65 | symbols. The libc.so archive also includes a number of other |
| 66 | object files, which also define symbols, some of which are the same |
| 67 | as those defined in libc.so.1. Correct linking requires that we |
| 68 | consider each object file in turn, and include it if it defines any |
| 69 | symbols we need. _bfd_generic_link_add_archive_symbols does not do |
| 70 | this; it looks through the list of undefined symbols, and includes |
| 71 | any object file which defines them. When this algorithm is used on |
| 72 | UnixWare, it winds up pulling in libc.so.1 early and defining a |
| 73 | bunch of symbols. This means that some of the other objects in the |
| 74 | archive are not included in the link, which is incorrect since they |
| 75 | precede libc.so.1 in the archive. |
| 76 | |
| 77 | Fortunately, ELF archive handling is simpler than that done by |
| 78 | _bfd_generic_link_add_archive_symbols, which has to allow for a.out |
| 79 | oddities. In ELF, if we find a symbol in the archive map, and the |
| 80 | symbol is currently undefined, we know that we must pull in that |
| 81 | object file. |
| 82 | |
| 83 | Unfortunately, we do have to make multiple passes over the symbol |
| 84 | table until nothing further is resolved. */ |
| 85 | |
| 86 | static boolean |
| 87 | elf_link_add_archive_symbols (abfd, info) |
| 88 | bfd *abfd; |
| 89 | struct bfd_link_info *info; |
| 90 | { |
| 91 | symindex c; |
| 92 | boolean *defined = NULL; |
| 93 | boolean *included = NULL; |
| 94 | carsym *symdefs; |
| 95 | boolean loop; |
| 96 | |
| 97 | if (! bfd_has_map (abfd)) |
| 98 | { |
| 99 | /* An empty archive is a special case. */ |
| 100 | if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL) |
| 101 | return true; |
| 102 | bfd_set_error (bfd_error_no_armap); |
| 103 | return false; |
| 104 | } |
| 105 | |
| 106 | /* Keep track of all symbols we know to be already defined, and all |
| 107 | files we know to be already included. This is to speed up the |
| 108 | second and subsequent passes. */ |
| 109 | c = bfd_ardata (abfd)->symdef_count; |
| 110 | if (c == 0) |
| 111 | return true; |
| 112 | defined = (boolean *) malloc (c * sizeof (boolean)); |
| 113 | included = (boolean *) malloc (c * sizeof (boolean)); |
| 114 | if (defined == (boolean *) NULL || included == (boolean *) NULL) |
| 115 | { |
| 116 | bfd_set_error (bfd_error_no_memory); |
| 117 | goto error_return; |
| 118 | } |
| 119 | memset (defined, 0, c * sizeof (boolean)); |
| 120 | memset (included, 0, c * sizeof (boolean)); |
| 121 | |
| 122 | symdefs = bfd_ardata (abfd)->symdefs; |
| 123 | |
| 124 | do |
| 125 | { |
| 126 | file_ptr last; |
| 127 | symindex i; |
| 128 | carsym *symdef; |
| 129 | carsym *symdefend; |
| 130 | |
| 131 | loop = false; |
| 132 | last = -1; |
| 133 | |
| 134 | symdef = symdefs; |
| 135 | symdefend = symdef + c; |
| 136 | for (i = 0; symdef < symdefend; symdef++, i++) |
| 137 | { |
| 138 | struct elf_link_hash_entry *h; |
| 139 | bfd *element; |
| 140 | struct bfd_link_hash_entry *undefs_tail; |
| 141 | symindex mark; |
| 142 | |
| 143 | if (defined[i] || included[i]) |
| 144 | continue; |
| 145 | if (symdef->file_offset == last) |
| 146 | { |
| 147 | included[i] = true; |
| 148 | continue; |
| 149 | } |
| 150 | |
| 151 | h = elf_link_hash_lookup (elf_hash_table (info), symdef->name, |
| 152 | false, false, false); |
| 153 | if (h == (struct elf_link_hash_entry *) NULL) |
| 154 | continue; |
| 155 | if (h->root.type != bfd_link_hash_undefined) |
| 156 | { |
| 157 | defined[i] = true; |
| 158 | continue; |
| 159 | } |
| 160 | |
| 161 | /* We need to include this archive member. */ |
| 162 | |
| 163 | element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset); |
| 164 | if (element == (bfd *) NULL) |
| 165 | goto error_return; |
| 166 | |
| 167 | if (! bfd_check_format (element, bfd_object)) |
| 168 | goto error_return; |
| 169 | |
| 170 | /* Doublecheck that we have not included this object |
| 171 | already--it should be impossible, but there may be |
| 172 | something wrong with the archive. */ |
| 173 | if (element->archive_pass != 0) |
| 174 | { |
| 175 | bfd_set_error (bfd_error_bad_value); |
| 176 | goto error_return; |
| 177 | } |
| 178 | element->archive_pass = 1; |
| 179 | |
| 180 | undefs_tail = info->hash->undefs_tail; |
| 181 | |
| 182 | if (! (*info->callbacks->add_archive_element) (info, element, |
| 183 | symdef->name)) |
| 184 | goto error_return; |
| 185 | if (! elf_link_add_object_symbols (element, info)) |
| 186 | goto error_return; |
| 187 | |
| 188 | /* If there are any new undefined symbols, we need to make |
| 189 | another pass through the archive in order to see whether |
| 190 | they can be defined. FIXME: This isn't perfect, because |
| 191 | common symbols wind up on undefs_tail and because an |
| 192 | undefined symbol which is defined later on in this pass |
| 193 | does not require another pass. This isn't a bug, but it |
| 194 | does make the code less efficient than it could be. */ |
| 195 | if (undefs_tail != info->hash->undefs_tail) |
| 196 | loop = true; |
| 197 | |
| 198 | /* Look backward to mark all symbols from this object file |
| 199 | which we have already seen in this pass. */ |
| 200 | mark = i; |
| 201 | do |
| 202 | { |
| 203 | included[mark] = true; |
| 204 | if (mark == 0) |
| 205 | break; |
| 206 | --mark; |
| 207 | } |
| 208 | while (symdefs[mark].file_offset == symdef->file_offset); |
| 209 | |
| 210 | /* We mark subsequent symbols from this object file as we go |
| 211 | on through the loop. */ |
| 212 | last = symdef->file_offset; |
| 213 | } |
| 214 | } |
| 215 | while (loop); |
| 216 | |
| 217 | free (defined); |
| 218 | free (included); |
| 219 | |
| 220 | return true; |
| 221 | |
| 222 | error_return: |
| 223 | if (defined != (boolean *) NULL) |
| 224 | free (defined); |
| 225 | if (included != (boolean *) NULL) |
| 226 | free (included); |
| 227 | return false; |
| 228 | } |
| 229 | |
| 230 | /* Add symbols from an ELF object file to the linker hash table. */ |
| 231 | |
| 232 | static boolean |
| 233 | elf_link_add_object_symbols (abfd, info) |
| 234 | bfd *abfd; |
| 235 | struct bfd_link_info *info; |
| 236 | { |
| 237 | boolean (*add_symbol_hook) PARAMS ((bfd *, struct bfd_link_info *, |
| 238 | const Elf_Internal_Sym *, |
| 239 | const char **, flagword *, |
| 240 | asection **, bfd_vma *)); |
| 241 | boolean (*check_relocs) PARAMS ((bfd *, struct bfd_link_info *, |
| 242 | asection *, const Elf_Internal_Rela *)); |
| 243 | boolean collect; |
| 244 | Elf_Internal_Shdr *hdr; |
| 245 | size_t symcount; |
| 246 | size_t extsymcount; |
| 247 | size_t extsymoff; |
| 248 | Elf_External_Sym *buf = NULL; |
| 249 | struct elf_link_hash_entry **sym_hash; |
| 250 | boolean dynamic; |
| 251 | Elf_External_Dyn *dynbuf = NULL; |
| 252 | struct elf_link_hash_entry *weaks; |
| 253 | Elf_External_Sym *esym; |
| 254 | Elf_External_Sym *esymend; |
| 255 | |
| 256 | add_symbol_hook = get_elf_backend_data (abfd)->elf_add_symbol_hook; |
| 257 | collect = get_elf_backend_data (abfd)->collect; |
| 258 | |
| 259 | /* A stripped shared library might only have a dynamic symbol table, |
| 260 | not a regular symbol table. In that case we can still go ahead |
| 261 | and link using the dynamic symbol table. */ |
| 262 | if (elf_onesymtab (abfd) == 0 |
| 263 | && elf_dynsymtab (abfd) != 0) |
| 264 | { |
| 265 | elf_onesymtab (abfd) = elf_dynsymtab (abfd); |
| 266 | elf_tdata (abfd)->symtab_hdr = elf_tdata (abfd)->dynsymtab_hdr; |
| 267 | } |
| 268 | |
| 269 | hdr = &elf_tdata (abfd)->symtab_hdr; |
| 270 | symcount = hdr->sh_size / sizeof (Elf_External_Sym); |
| 271 | |
| 272 | /* The sh_info field of the symtab header tells us where the |
| 273 | external symbols start. We don't care about the local symbols at |
| 274 | this point. */ |
| 275 | if (elf_bad_symtab (abfd)) |
| 276 | { |
| 277 | extsymcount = symcount; |
| 278 | extsymoff = 0; |
| 279 | } |
| 280 | else |
| 281 | { |
| 282 | extsymcount = symcount - hdr->sh_info; |
| 283 | extsymoff = hdr->sh_info; |
| 284 | } |
| 285 | |
| 286 | buf = (Elf_External_Sym *) malloc (extsymcount * sizeof (Elf_External_Sym)); |
| 287 | if (buf == NULL && extsymcount != 0) |
| 288 | { |
| 289 | bfd_set_error (bfd_error_no_memory); |
| 290 | goto error_return; |
| 291 | } |
| 292 | |
| 293 | /* We store a pointer to the hash table entry for each external |
| 294 | symbol. */ |
| 295 | sym_hash = ((struct elf_link_hash_entry **) |
| 296 | bfd_alloc (abfd, |
| 297 | extsymcount * sizeof (struct elf_link_hash_entry *))); |
| 298 | if (sym_hash == NULL) |
| 299 | { |
| 300 | bfd_set_error (bfd_error_no_memory); |
| 301 | goto error_return; |
| 302 | } |
| 303 | elf_sym_hashes (abfd) = sym_hash; |
| 304 | |
| 305 | if (elf_elfheader (abfd)->e_type != ET_DYN) |
| 306 | { |
| 307 | dynamic = false; |
| 308 | |
| 309 | /* If we are creating a shared library, create all the dynamic |
| 310 | sections immediately. We need to attach them to something, |
| 311 | so we attach them to this BFD, provided it is the right |
| 312 | format. FIXME: If there are no input BFD's of the same |
| 313 | format as the output, we can't make a shared library. */ |
| 314 | if (info->shared |
| 315 | && ! elf_hash_table (info)->dynamic_sections_created |
| 316 | && abfd->xvec == info->hash->creator) |
| 317 | { |
| 318 | if (! elf_link_create_dynamic_sections (abfd, info)) |
| 319 | goto error_return; |
| 320 | } |
| 321 | } |
| 322 | else |
| 323 | { |
| 324 | asection *s; |
| 325 | boolean add_needed; |
| 326 | const char *name; |
| 327 | bfd_size_type oldsize; |
| 328 | bfd_size_type strindex; |
| 329 | |
| 330 | dynamic = true; |
| 331 | |
| 332 | /* You can't use -r against a dynamic object. Also, there's no |
| 333 | hope of using a dynamic object which does not exactly match |
| 334 | the format of the output file. */ |
| 335 | if (info->relocateable |
| 336 | || info->hash->creator != abfd->xvec) |
| 337 | { |
| 338 | bfd_set_error (bfd_error_invalid_operation); |
| 339 | goto error_return; |
| 340 | } |
| 341 | |
| 342 | /* Find the name to use in a DT_NEEDED entry that refers to this |
| 343 | object. If the object has a DT_SONAME entry, we use it. |
| 344 | Otherwise, if the generic linker stuck something in |
| 345 | elf_dt_needed_name, we use that. Otherwise, we just use the |
| 346 | file name. If the generic linker put a null string into |
| 347 | elf_dt_needed_name, we don't make a DT_NEEDED entry at all, |
| 348 | even if there is a DT_SONAME entry. */ |
| 349 | add_needed = true; |
| 350 | name = bfd_get_filename (abfd); |
| 351 | if (elf_dt_needed_name (abfd) != NULL) |
| 352 | { |
| 353 | name = elf_dt_needed_name (abfd); |
| 354 | if (*name == '\0') |
| 355 | add_needed = false; |
| 356 | } |
| 357 | s = bfd_get_section_by_name (abfd, ".dynamic"); |
| 358 | if (s != NULL) |
| 359 | { |
| 360 | Elf_External_Dyn *extdyn; |
| 361 | Elf_External_Dyn *extdynend; |
| 362 | int elfsec; |
| 363 | unsigned long link; |
| 364 | |
| 365 | dynbuf = (Elf_External_Dyn *) malloc ((size_t) s->_raw_size); |
| 366 | if (dynbuf == NULL) |
| 367 | { |
| 368 | bfd_set_error (bfd_error_no_memory); |
| 369 | goto error_return; |
| 370 | } |
| 371 | |
| 372 | if (! bfd_get_section_contents (abfd, s, (PTR) dynbuf, |
| 373 | (file_ptr) 0, s->_raw_size)) |
| 374 | goto error_return; |
| 375 | |
| 376 | elfsec = _bfd_elf_section_from_bfd_section (abfd, s); |
| 377 | if (elfsec == -1) |
| 378 | goto error_return; |
| 379 | link = elf_elfsections (abfd)[elfsec]->sh_link; |
| 380 | |
| 381 | extdyn = dynbuf; |
| 382 | extdynend = extdyn + s->_raw_size / sizeof (Elf_External_Dyn); |
| 383 | for (; extdyn < extdynend; extdyn++) |
| 384 | { |
| 385 | Elf_Internal_Dyn dyn; |
| 386 | |
| 387 | elf_swap_dyn_in (abfd, extdyn, &dyn); |
| 388 | if (add_needed && dyn.d_tag == DT_SONAME) |
| 389 | { |
| 390 | name = bfd_elf_string_from_elf_section (abfd, link, |
| 391 | dyn.d_un.d_val); |
| 392 | if (name == NULL) |
| 393 | goto error_return; |
| 394 | } |
| 395 | if (dyn.d_tag == DT_NEEDED) |
| 396 | { |
| 397 | struct bfd_elf_link_needed_list *n, **pn; |
| 398 | char *fnm, *anm; |
| 399 | |
| 400 | n = (struct bfd_elf_link_needed_list *) |
| 401 | bfd_alloc (abfd, |
| 402 | sizeof (struct bfd_elf_link_needed_list)); |
| 403 | fnm = bfd_elf_string_from_elf_section (abfd, link, |
| 404 | dyn.d_un.d_val); |
| 405 | if (n == NULL || fnm == NULL) |
| 406 | goto error_return; |
| 407 | anm = bfd_alloc (abfd, strlen (fnm) + 1); |
| 408 | if (anm == NULL) |
| 409 | goto error_return; |
| 410 | strcpy (anm, fnm); |
| 411 | n->name = anm; |
| 412 | n->by = abfd; |
| 413 | n->next = NULL; |
| 414 | for (pn = &elf_hash_table (info)->needed; |
| 415 | *pn != NULL; |
| 416 | pn = &(*pn)->next) |
| 417 | ; |
| 418 | *pn = n; |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | free (dynbuf); |
| 423 | dynbuf = NULL; |
| 424 | } |
| 425 | |
| 426 | /* We do not want to include any of the sections in a dynamic |
| 427 | object in the output file. We hack by simply clobbering the |
| 428 | list of sections in the BFD. This could be handled more |
| 429 | cleanly by, say, a new section flag; the existing |
| 430 | SEC_NEVER_LOAD flag is not the one we want, because that one |
| 431 | still implies that the section takes up space in the output |
| 432 | file. */ |
| 433 | abfd->sections = NULL; |
| 434 | |
| 435 | /* If this is the first dynamic object found in the link, create |
| 436 | the special sections required for dynamic linking. */ |
| 437 | if (! elf_hash_table (info)->dynamic_sections_created) |
| 438 | { |
| 439 | if (! elf_link_create_dynamic_sections (abfd, info)) |
| 440 | goto error_return; |
| 441 | } |
| 442 | |
| 443 | if (add_needed) |
| 444 | { |
| 445 | /* Add a DT_NEEDED entry for this dynamic object. */ |
| 446 | oldsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr); |
| 447 | strindex = _bfd_stringtab_add (elf_hash_table (info)->dynstr, name, |
| 448 | true, false); |
| 449 | if (strindex == (bfd_size_type) -1) |
| 450 | goto error_return; |
| 451 | |
| 452 | if (oldsize == _bfd_stringtab_size (elf_hash_table (info)->dynstr)) |
| 453 | { |
| 454 | asection *sdyn; |
| 455 | Elf_External_Dyn *dyncon, *dynconend; |
| 456 | |
| 457 | /* The hash table size did not change, which means that |
| 458 | the dynamic object name was already entered. If we |
| 459 | have already included this dynamic object in the |
| 460 | link, just ignore it. There is no reason to include |
| 461 | a particular dynamic object more than once. */ |
| 462 | sdyn = bfd_get_section_by_name (elf_hash_table (info)->dynobj, |
| 463 | ".dynamic"); |
| 464 | BFD_ASSERT (sdyn != NULL); |
| 465 | |
| 466 | dyncon = (Elf_External_Dyn *) sdyn->contents; |
| 467 | dynconend = (Elf_External_Dyn *) (sdyn->contents + |
| 468 | sdyn->_raw_size); |
| 469 | for (; dyncon < dynconend; dyncon++) |
| 470 | { |
| 471 | Elf_Internal_Dyn dyn; |
| 472 | |
| 473 | elf_swap_dyn_in (elf_hash_table (info)->dynobj, dyncon, |
| 474 | &dyn); |
| 475 | if (dyn.d_tag == DT_NEEDED |
| 476 | && dyn.d_un.d_val == strindex) |
| 477 | { |
| 478 | if (buf != NULL) |
| 479 | free (buf); |
| 480 | return true; |
| 481 | } |
| 482 | } |
| 483 | } |
| 484 | |
| 485 | if (! elf_add_dynamic_entry (info, DT_NEEDED, strindex)) |
| 486 | goto error_return; |
| 487 | } |
| 488 | } |
| 489 | |
| 490 | if (bfd_seek (abfd, |
| 491 | hdr->sh_offset + extsymoff * sizeof (Elf_External_Sym), |
| 492 | SEEK_SET) != 0 |
| 493 | || (bfd_read ((PTR) buf, sizeof (Elf_External_Sym), extsymcount, abfd) |
| 494 | != extsymcount * sizeof (Elf_External_Sym))) |
| 495 | goto error_return; |
| 496 | |
| 497 | weaks = NULL; |
| 498 | |
| 499 | esymend = buf + extsymcount; |
| 500 | for (esym = buf; esym < esymend; esym++, sym_hash++) |
| 501 | { |
| 502 | Elf_Internal_Sym sym; |
| 503 | int bind; |
| 504 | bfd_vma value; |
| 505 | asection *sec; |
| 506 | flagword flags; |
| 507 | const char *name; |
| 508 | struct elf_link_hash_entry *h = NULL; |
| 509 | boolean definition; |
| 510 | |
| 511 | elf_swap_symbol_in (abfd, esym, &sym); |
| 512 | |
| 513 | flags = BSF_NO_FLAGS; |
| 514 | sec = NULL; |
| 515 | value = sym.st_value; |
| 516 | *sym_hash = NULL; |
| 517 | |
| 518 | bind = ELF_ST_BIND (sym.st_info); |
| 519 | if (bind == STB_LOCAL) |
| 520 | { |
| 521 | /* This should be impossible, since ELF requires that all |
| 522 | global symbols follow all local symbols, and that sh_info |
| 523 | point to the first global symbol. Unfortunatealy, Irix 5 |
| 524 | screws this up. */ |
| 525 | continue; |
| 526 | } |
| 527 | else if (bind == STB_GLOBAL) |
| 528 | { |
| 529 | if (sym.st_shndx != SHN_UNDEF |
| 530 | && sym.st_shndx != SHN_COMMON) |
| 531 | flags = BSF_GLOBAL; |
| 532 | else |
| 533 | flags = 0; |
| 534 | } |
| 535 | else if (bind == STB_WEAK) |
| 536 | flags = BSF_WEAK; |
| 537 | else |
| 538 | { |
| 539 | /* Leave it up to the processor backend. */ |
| 540 | } |
| 541 | |
| 542 | if (sym.st_shndx == SHN_UNDEF) |
| 543 | sec = bfd_und_section_ptr; |
| 544 | else if (sym.st_shndx > 0 && sym.st_shndx < SHN_LORESERVE) |
| 545 | { |
| 546 | sec = section_from_elf_index (abfd, sym.st_shndx); |
| 547 | if (sec != NULL) |
| 548 | value -= sec->vma; |
| 549 | else |
| 550 | sec = bfd_abs_section_ptr; |
| 551 | } |
| 552 | else if (sym.st_shndx == SHN_ABS) |
| 553 | sec = bfd_abs_section_ptr; |
| 554 | else if (sym.st_shndx == SHN_COMMON) |
| 555 | { |
| 556 | sec = bfd_com_section_ptr; |
| 557 | /* What ELF calls the size we call the value. What ELF |
| 558 | calls the value we call the alignment. */ |
| 559 | value = sym.st_size; |
| 560 | } |
| 561 | else |
| 562 | { |
| 563 | /* Leave it up to the processor backend. */ |
| 564 | } |
| 565 | |
| 566 | name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link, sym.st_name); |
| 567 | if (name == (const char *) NULL) |
| 568 | goto error_return; |
| 569 | |
| 570 | if (add_symbol_hook) |
| 571 | { |
| 572 | if (! (*add_symbol_hook) (abfd, info, &sym, &name, &flags, &sec, |
| 573 | &value)) |
| 574 | goto error_return; |
| 575 | |
| 576 | /* The hook function sets the name to NULL if this symbol |
| 577 | should be skipped for some reason. */ |
| 578 | if (name == (const char *) NULL) |
| 579 | continue; |
| 580 | } |
| 581 | |
| 582 | /* Sanity check that all possibilities were handled. */ |
| 583 | if (sec == (asection *) NULL) |
| 584 | { |
| 585 | bfd_set_error (bfd_error_bad_value); |
| 586 | goto error_return; |
| 587 | } |
| 588 | |
| 589 | if (bfd_is_und_section (sec) |
| 590 | || bfd_is_com_section (sec)) |
| 591 | definition = false; |
| 592 | else |
| 593 | definition = true; |
| 594 | |
| 595 | if (info->hash->creator->flavour == bfd_target_elf_flavour) |
| 596 | { |
| 597 | /* We need to look up the symbol now in order to get some of |
| 598 | the dynamic object handling right. We pass the hash |
| 599 | table entry in to _bfd_generic_link_add_one_symbol so |
| 600 | that it does not have to look it up again. */ |
| 601 | h = elf_link_hash_lookup (elf_hash_table (info), name, |
| 602 | true, false, false); |
| 603 | if (h == NULL) |
| 604 | goto error_return; |
| 605 | *sym_hash = h; |
| 606 | |
| 607 | /* If we are looking at a dynamic object, and this is a |
| 608 | definition, we need to see if it has already been defined |
| 609 | by some other object. If it has, we want to use the |
| 610 | existing definition, and we do not want to report a |
| 611 | multiple symbol definition error; we do this by |
| 612 | clobbering sec to be bfd_und_section_ptr. */ |
| 613 | if (dynamic && definition) |
| 614 | { |
| 615 | if (h->root.type == bfd_link_hash_defined |
| 616 | || h->root.type == bfd_link_hash_defweak) |
| 617 | sec = bfd_und_section_ptr; |
| 618 | } |
| 619 | |
| 620 | /* Similarly, if we are not looking at a dynamic object, and |
| 621 | we have a definition, we want to override any definition |
| 622 | we may have from a dynamic object. Symbols from regular |
| 623 | files always take precedence over symbols from dynamic |
| 624 | objects, even if they are defined after the dynamic |
| 625 | object in the link. */ |
| 626 | if (! dynamic |
| 627 | && definition |
| 628 | && (h->root.type == bfd_link_hash_defined |
| 629 | || h->root.type == bfd_link_hash_defweak) |
| 630 | && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 |
| 631 | && (bfd_get_flavour (h->root.u.def.section->owner) |
| 632 | == bfd_target_elf_flavour) |
| 633 | && (elf_elfheader (h->root.u.def.section->owner)->e_type |
| 634 | == ET_DYN)) |
| 635 | { |
| 636 | /* Change the hash table entry to undefined, and let |
| 637 | _bfd_generic_link_add_one_symbol do the right thing |
| 638 | with the new definition. */ |
| 639 | h->root.type = bfd_link_hash_undefined; |
| 640 | h->root.u.undef.abfd = h->root.u.def.section->owner; |
| 641 | } |
| 642 | } |
| 643 | |
| 644 | if (! (_bfd_generic_link_add_one_symbol |
| 645 | (info, abfd, name, flags, sec, value, (const char *) NULL, |
| 646 | false, collect, (struct bfd_link_hash_entry **) sym_hash))) |
| 647 | goto error_return; |
| 648 | |
| 649 | if (dynamic |
| 650 | && definition |
| 651 | && (flags & BSF_WEAK) != 0 |
| 652 | && ELF_ST_TYPE (sym.st_info) != STT_FUNC |
| 653 | && info->hash->creator->flavour == bfd_target_elf_flavour |
| 654 | && (*sym_hash)->weakdef == NULL) |
| 655 | { |
| 656 | /* Keep a list of all weak defined non function symbols from |
| 657 | a dynamic object, using the weakdef field. Later in this |
| 658 | function we will set the weakdef field to the correct |
| 659 | value. We only put non-function symbols from dynamic |
| 660 | objects on this list, because that happens to be the only |
| 661 | time we need to know the normal symbol corresponding to a |
| 662 | weak symbol, and the information is time consuming to |
| 663 | figure out. If the weakdef field is not already NULL, |
| 664 | then this symbol was already defined by some previous |
| 665 | dynamic object, and we will be using that previous |
| 666 | definition anyhow. */ |
| 667 | |
| 668 | (*sym_hash)->weakdef = weaks; |
| 669 | weaks = *sym_hash; |
| 670 | } |
| 671 | |
| 672 | /* Get the alignment of a common symbol. */ |
| 673 | if (sym.st_shndx == SHN_COMMON |
| 674 | && (*sym_hash)->root.type == bfd_link_hash_common) |
| 675 | (*sym_hash)->root.u.c.p->alignment_power = bfd_log2 (sym.st_value); |
| 676 | |
| 677 | if (info->hash->creator->flavour == bfd_target_elf_flavour) |
| 678 | { |
| 679 | int old_flags; |
| 680 | boolean dynsym; |
| 681 | int new_flag; |
| 682 | |
| 683 | /* Remember the symbol size and type. */ |
| 684 | if (sym.st_size != 0) |
| 685 | { |
| 686 | /* FIXME: We should probably somehow give a warning if |
| 687 | the symbol size changes. */ |
| 688 | h->size = sym.st_size; |
| 689 | } |
| 690 | if (ELF_ST_TYPE (sym.st_info) != STT_NOTYPE) |
| 691 | { |
| 692 | /* FIXME: We should probably somehow give a warning if |
| 693 | the symbol type changes. */ |
| 694 | h->type = ELF_ST_TYPE (sym.st_info); |
| 695 | } |
| 696 | |
| 697 | /* Set a flag in the hash table entry indicating the type of |
| 698 | reference or definition we just found. Keep a count of |
| 699 | the number of dynamic symbols we find. A dynamic symbol |
| 700 | is one which is referenced or defined by both a regular |
| 701 | object and a shared object, or one which is referenced or |
| 702 | defined by more than one shared object. */ |
| 703 | old_flags = h->elf_link_hash_flags; |
| 704 | dynsym = false; |
| 705 | if (! dynamic) |
| 706 | { |
| 707 | if (! definition) |
| 708 | new_flag = ELF_LINK_HASH_REF_REGULAR; |
| 709 | else |
| 710 | new_flag = ELF_LINK_HASH_DEF_REGULAR; |
| 711 | if (info->shared |
| 712 | || (old_flags & (ELF_LINK_HASH_DEF_DYNAMIC |
| 713 | | ELF_LINK_HASH_REF_DYNAMIC)) != 0) |
| 714 | dynsym = true; |
| 715 | } |
| 716 | else |
| 717 | { |
| 718 | if (! definition) |
| 719 | new_flag = ELF_LINK_HASH_REF_DYNAMIC; |
| 720 | else |
| 721 | new_flag = ELF_LINK_HASH_DEF_DYNAMIC; |
| 722 | if ((old_flags & new_flag) != 0 |
| 723 | || (old_flags & (ELF_LINK_HASH_DEF_REGULAR |
| 724 | | ELF_LINK_HASH_REF_REGULAR)) != 0) |
| 725 | dynsym = true; |
| 726 | } |
| 727 | |
| 728 | h->elf_link_hash_flags |= new_flag; |
| 729 | if (dynsym && h->dynindx == -1) |
| 730 | { |
| 731 | if (! _bfd_elf_link_record_dynamic_symbol (info, h)) |
| 732 | goto error_return; |
| 733 | } |
| 734 | } |
| 735 | } |
| 736 | |
| 737 | /* Now set the weakdefs field correctly for all the weak defined |
| 738 | symbols we found. The only way to do this is to search all the |
| 739 | symbols. Since we only need the information for non functions in |
| 740 | dynamic objects, that's the only time we actually put anything on |
| 741 | the list WEAKS. We need this information so that if a regular |
| 742 | object refers to a symbol defined weakly in a dynamic object, the |
| 743 | real symbol in the dynamic object is also put in the dynamic |
| 744 | symbols; we also must arrange for both symbols to point to the |
| 745 | same memory location. We could handle the general case of symbol |
| 746 | aliasing, but a general symbol alias can only be generated in |
| 747 | assembler code, handling it correctly would be very time |
| 748 | consuming, and other ELF linkers don't handle general aliasing |
| 749 | either. */ |
| 750 | while (weaks != NULL) |
| 751 | { |
| 752 | struct elf_link_hash_entry *hlook; |
| 753 | asection *slook; |
| 754 | bfd_vma vlook; |
| 755 | struct elf_link_hash_entry **hpp; |
| 756 | struct elf_link_hash_entry **hppend; |
| 757 | |
| 758 | hlook = weaks; |
| 759 | weaks = hlook->weakdef; |
| 760 | hlook->weakdef = NULL; |
| 761 | |
| 762 | BFD_ASSERT (hlook->root.type == bfd_link_hash_defined |
| 763 | || hlook->root.type == bfd_link_hash_defweak |
| 764 | || hlook->root.type == bfd_link_hash_common |
| 765 | || hlook->root.type == bfd_link_hash_indirect); |
| 766 | slook = hlook->root.u.def.section; |
| 767 | vlook = hlook->root.u.def.value; |
| 768 | |
| 769 | hpp = elf_sym_hashes (abfd); |
| 770 | hppend = hpp + extsymcount; |
| 771 | for (; hpp < hppend; hpp++) |
| 772 | { |
| 773 | struct elf_link_hash_entry *h; |
| 774 | |
| 775 | h = *hpp; |
| 776 | if (h != NULL && h != hlook |
| 777 | && (h->root.type == bfd_link_hash_defined |
| 778 | || h->root.type == bfd_link_hash_defweak) |
| 779 | && h->root.u.def.section == slook |
| 780 | && h->root.u.def.value == vlook) |
| 781 | { |
| 782 | hlook->weakdef = h; |
| 783 | |
| 784 | /* If the weak definition is in the list of dynamic |
| 785 | symbols, make sure the real definition is put there |
| 786 | as well. */ |
| 787 | if (hlook->dynindx != -1 |
| 788 | && h->dynindx == -1) |
| 789 | { |
| 790 | if (! _bfd_elf_link_record_dynamic_symbol (info, h)) |
| 791 | goto error_return; |
| 792 | } |
| 793 | |
| 794 | break; |
| 795 | } |
| 796 | } |
| 797 | } |
| 798 | |
| 799 | if (buf != NULL) |
| 800 | { |
| 801 | free (buf); |
| 802 | buf = NULL; |
| 803 | } |
| 804 | |
| 805 | /* If this object is the same format as the output object, and it is |
| 806 | not a shared library, then let the backend look through the |
| 807 | relocs. |
| 808 | |
| 809 | This is required to build global offset table entries and to |
| 810 | arrange for dynamic relocs. It is not required for the |
| 811 | particular common case of linking non PIC code, even when linking |
| 812 | against shared libraries, but unfortunately there is no way of |
| 813 | knowing whether an object file has been compiled PIC or not. |
| 814 | Looking through the relocs is not particularly time consuming. |
| 815 | The problem is that we must either (1) keep the relocs in memory, |
| 816 | which causes the linker to require additional runtime memory or |
| 817 | (2) read the relocs twice from the input file, which wastes time. |
| 818 | This would be a good case for using mmap. |
| 819 | |
| 820 | I have no idea how to handle linking PIC code into a file of a |
| 821 | different format. It probably can't be done. */ |
| 822 | check_relocs = get_elf_backend_data (abfd)->check_relocs; |
| 823 | if (! dynamic |
| 824 | && abfd->xvec == info->hash->creator |
| 825 | && check_relocs != NULL) |
| 826 | { |
| 827 | asection *o; |
| 828 | |
| 829 | for (o = abfd->sections; o != NULL; o = o->next) |
| 830 | { |
| 831 | Elf_Internal_Rela *internal_relocs; |
| 832 | boolean ok; |
| 833 | |
| 834 | if ((o->flags & SEC_RELOC) == 0 |
| 835 | || o->reloc_count == 0) |
| 836 | continue; |
| 837 | |
| 838 | /* I believe we can ignore the relocs for any section which |
| 839 | does not form part of the final process image, such as a |
| 840 | debugging section. */ |
| 841 | if ((o->flags & SEC_ALLOC) == 0) |
| 842 | continue; |
| 843 | |
| 844 | internal_relocs = elf_link_read_relocs (abfd, o, (PTR) NULL, |
| 845 | (Elf_Internal_Rela *) NULL, |
| 846 | info->keep_memory); |
| 847 | if (internal_relocs == NULL) |
| 848 | goto error_return; |
| 849 | |
| 850 | ok = (*check_relocs) (abfd, info, o, internal_relocs); |
| 851 | |
| 852 | if (! info->keep_memory) |
| 853 | free (internal_relocs); |
| 854 | |
| 855 | if (! ok) |
| 856 | goto error_return; |
| 857 | } |
| 858 | } |
| 859 | |
| 860 | return true; |
| 861 | |
| 862 | error_return: |
| 863 | if (buf != NULL) |
| 864 | free (buf); |
| 865 | if (dynbuf != NULL) |
| 866 | free (dynbuf); |
| 867 | return false; |
| 868 | } |
| 869 | |
| 870 | /* Create some sections which will be filled in with dynamic linking |
| 871 | information. ABFD is an input file which requires dynamic sections |
| 872 | to be created. The dynamic sections take up virtual memory space |
| 873 | when the final executable is run, so we need to create them before |
| 874 | addresses are assigned to the output sections. We work out the |
| 875 | actual contents and size of these sections later. */ |
| 876 | |
| 877 | boolean |
| 878 | elf_link_create_dynamic_sections (abfd, info) |
| 879 | bfd *abfd; |
| 880 | struct bfd_link_info *info; |
| 881 | { |
| 882 | flagword flags; |
| 883 | register asection *s; |
| 884 | struct elf_link_hash_entry *h; |
| 885 | struct elf_backend_data *bed; |
| 886 | |
| 887 | if (elf_hash_table (info)->dynamic_sections_created) |
| 888 | return true; |
| 889 | |
| 890 | /* Make sure that all dynamic sections use the same input BFD. */ |
| 891 | if (elf_hash_table (info)->dynobj == NULL) |
| 892 | elf_hash_table (info)->dynobj = abfd; |
| 893 | else |
| 894 | abfd = elf_hash_table (info)->dynobj; |
| 895 | |
| 896 | /* Note that we set the SEC_IN_MEMORY flag for all of these |
| 897 | sections. */ |
| 898 | flags = SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY; |
| 899 | |
| 900 | /* A dynamically linked executable has a .interp section, but a |
| 901 | shared library does not. */ |
| 902 | if (! info->shared) |
| 903 | { |
| 904 | s = bfd_make_section (abfd, ".interp"); |
| 905 | if (s == NULL |
| 906 | || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)) |
| 907 | return false; |
| 908 | } |
| 909 | |
| 910 | s = bfd_make_section (abfd, ".dynsym"); |
| 911 | if (s == NULL |
| 912 | || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY) |
| 913 | || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN)) |
| 914 | return false; |
| 915 | |
| 916 | s = bfd_make_section (abfd, ".dynstr"); |
| 917 | if (s == NULL |
| 918 | || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY)) |
| 919 | return false; |
| 920 | |
| 921 | /* Create a strtab to hold the dynamic symbol names. */ |
| 922 | if (elf_hash_table (info)->dynstr == NULL) |
| 923 | { |
| 924 | elf_hash_table (info)->dynstr = elf_stringtab_init (); |
| 925 | if (elf_hash_table (info)->dynstr == NULL) |
| 926 | return false; |
| 927 | } |
| 928 | |
| 929 | s = bfd_make_section (abfd, ".dynamic"); |
| 930 | if (s == NULL |
| 931 | || ! bfd_set_section_flags (abfd, s, flags) |
| 932 | || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN)) |
| 933 | return false; |
| 934 | |
| 935 | /* The special symbol _DYNAMIC is always set to the start of the |
| 936 | .dynamic section. This call occurs before we have processed the |
| 937 | symbols for any dynamic object, so we don't have to worry about |
| 938 | overriding a dynamic definition. We could set _DYNAMIC in a |
| 939 | linker script, but we only want to define it if we are, in fact, |
| 940 | creating a .dynamic section. We don't want to define it if there |
| 941 | is no .dynamic section, since on some ELF platforms the start up |
| 942 | code examines it to decide how to initialize the process. */ |
| 943 | h = NULL; |
| 944 | if (! (_bfd_generic_link_add_one_symbol |
| 945 | (info, abfd, "_DYNAMIC", BSF_GLOBAL, s, (bfd_vma) 0, |
| 946 | (const char *) NULL, false, get_elf_backend_data (abfd)->collect, |
| 947 | (struct bfd_link_hash_entry **) &h))) |
| 948 | return false; |
| 949 | h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR; |
| 950 | h->type = STT_OBJECT; |
| 951 | |
| 952 | if (info->shared |
| 953 | && ! _bfd_elf_link_record_dynamic_symbol (info, h)) |
| 954 | return false; |
| 955 | |
| 956 | s = bfd_make_section (abfd, ".hash"); |
| 957 | if (s == NULL |
| 958 | || ! bfd_set_section_flags (abfd, s, flags | SEC_READONLY) |
| 959 | || ! bfd_set_section_alignment (abfd, s, LOG_FILE_ALIGN)) |
| 960 | return false; |
| 961 | |
| 962 | /* Let the backend create the rest of the sections. This lets the |
| 963 | backend set the right flags. The backend will normally create |
| 964 | the .got and .plt sections. */ |
| 965 | bed = get_elf_backend_data (abfd); |
| 966 | if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info)) |
| 967 | return false; |
| 968 | |
| 969 | elf_hash_table (info)->dynamic_sections_created = true; |
| 970 | |
| 971 | return true; |
| 972 | } |
| 973 | |
| 974 | /* Add an entry to the .dynamic table. */ |
| 975 | |
| 976 | boolean |
| 977 | elf_add_dynamic_entry (info, tag, val) |
| 978 | struct bfd_link_info *info; |
| 979 | bfd_vma tag; |
| 980 | bfd_vma val; |
| 981 | { |
| 982 | Elf_Internal_Dyn dyn; |
| 983 | bfd *dynobj; |
| 984 | asection *s; |
| 985 | size_t newsize; |
| 986 | bfd_byte *newcontents; |
| 987 | |
| 988 | dynobj = elf_hash_table (info)->dynobj; |
| 989 | |
| 990 | s = bfd_get_section_by_name (dynobj, ".dynamic"); |
| 991 | BFD_ASSERT (s != NULL); |
| 992 | |
| 993 | newsize = s->_raw_size + sizeof (Elf_External_Dyn); |
| 994 | if (s->contents == NULL) |
| 995 | newcontents = (bfd_byte *) malloc (newsize); |
| 996 | else |
| 997 | newcontents = (bfd_byte *) realloc (s->contents, newsize); |
| 998 | if (newcontents == NULL) |
| 999 | { |
| 1000 | bfd_set_error (bfd_error_no_memory); |
| 1001 | return false; |
| 1002 | } |
| 1003 | |
| 1004 | dyn.d_tag = tag; |
| 1005 | dyn.d_un.d_val = val; |
| 1006 | elf_swap_dyn_out (dynobj, &dyn, |
| 1007 | (Elf_External_Dyn *) (newcontents + s->_raw_size)); |
| 1008 | |
| 1009 | s->_raw_size = newsize; |
| 1010 | s->contents = newcontents; |
| 1011 | |
| 1012 | return true; |
| 1013 | } |
| 1014 | |
| 1015 | /* Read and swap the relocs for a section. They may have been cached. |
| 1016 | If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are not NULL, |
| 1017 | they are used as buffers to read into. They are known to be large |
| 1018 | enough. If the INTERNAL_RELOCS relocs argument is NULL, the return |
| 1019 | value is allocated using either malloc or bfd_alloc, according to |
| 1020 | the KEEP_MEMORY argument. */ |
| 1021 | |
| 1022 | static Elf_Internal_Rela * |
| 1023 | elf_link_read_relocs (abfd, o, external_relocs, internal_relocs, keep_memory) |
| 1024 | bfd *abfd; |
| 1025 | asection *o; |
| 1026 | PTR external_relocs; |
| 1027 | Elf_Internal_Rela *internal_relocs; |
| 1028 | boolean keep_memory; |
| 1029 | { |
| 1030 | Elf_Internal_Shdr *rel_hdr; |
| 1031 | PTR alloc1 = NULL; |
| 1032 | Elf_Internal_Rela *alloc2 = NULL; |
| 1033 | |
| 1034 | if (elf_section_data (o)->relocs != NULL) |
| 1035 | return elf_section_data (o)->relocs; |
| 1036 | |
| 1037 | if (o->reloc_count == 0) |
| 1038 | return NULL; |
| 1039 | |
| 1040 | rel_hdr = &elf_section_data (o)->rel_hdr; |
| 1041 | |
| 1042 | if (internal_relocs == NULL) |
| 1043 | { |
| 1044 | size_t size; |
| 1045 | |
| 1046 | size = o->reloc_count * sizeof (Elf_Internal_Rela); |
| 1047 | if (keep_memory) |
| 1048 | internal_relocs = (Elf_Internal_Rela *) bfd_alloc (abfd, size); |
| 1049 | else |
| 1050 | internal_relocs = alloc2 = (Elf_Internal_Rela *) malloc (size); |
| 1051 | if (internal_relocs == NULL) |
| 1052 | { |
| 1053 | bfd_set_error (bfd_error_no_memory); |
| 1054 | goto error_return; |
| 1055 | } |
| 1056 | } |
| 1057 | |
| 1058 | if (external_relocs == NULL) |
| 1059 | { |
| 1060 | alloc1 = (PTR) malloc ((size_t) rel_hdr->sh_size); |
| 1061 | if (alloc1 == NULL) |
| 1062 | { |
| 1063 | bfd_set_error (bfd_error_no_memory); |
| 1064 | goto error_return; |
| 1065 | } |
| 1066 | external_relocs = alloc1; |
| 1067 | } |
| 1068 | |
| 1069 | if ((bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0) |
| 1070 | || (bfd_read (external_relocs, 1, rel_hdr->sh_size, abfd) |
| 1071 | != rel_hdr->sh_size)) |
| 1072 | goto error_return; |
| 1073 | |
| 1074 | /* Swap in the relocs. For convenience, we always produce an |
| 1075 | Elf_Internal_Rela array; if the relocs are Rel, we set the addend |
| 1076 | to 0. */ |
| 1077 | if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel)) |
| 1078 | { |
| 1079 | Elf_External_Rel *erel; |
| 1080 | Elf_External_Rel *erelend; |
| 1081 | Elf_Internal_Rela *irela; |
| 1082 | |
| 1083 | erel = (Elf_External_Rel *) external_relocs; |
| 1084 | erelend = erel + o->reloc_count; |
| 1085 | irela = internal_relocs; |
| 1086 | for (; erel < erelend; erel++, irela++) |
| 1087 | { |
| 1088 | Elf_Internal_Rel irel; |
| 1089 | |
| 1090 | elf_swap_reloc_in (abfd, erel, &irel); |
| 1091 | irela->r_offset = irel.r_offset; |
| 1092 | irela->r_info = irel.r_info; |
| 1093 | irela->r_addend = 0; |
| 1094 | } |
| 1095 | } |
| 1096 | else |
| 1097 | { |
| 1098 | Elf_External_Rela *erela; |
| 1099 | Elf_External_Rela *erelaend; |
| 1100 | Elf_Internal_Rela *irela; |
| 1101 | |
| 1102 | BFD_ASSERT (rel_hdr->sh_entsize == sizeof (Elf_External_Rela)); |
| 1103 | |
| 1104 | erela = (Elf_External_Rela *) external_relocs; |
| 1105 | erelaend = erela + o->reloc_count; |
| 1106 | irela = internal_relocs; |
| 1107 | for (; erela < erelaend; erela++, irela++) |
| 1108 | elf_swap_reloca_in (abfd, erela, irela); |
| 1109 | } |
| 1110 | |
| 1111 | /* Cache the results for next time, if we can. */ |
| 1112 | if (keep_memory) |
| 1113 | elf_section_data (o)->relocs = internal_relocs; |
| 1114 | |
| 1115 | if (alloc1 != NULL) |
| 1116 | free (alloc1); |
| 1117 | |
| 1118 | /* Don't free alloc2, since if it was allocated we are passing it |
| 1119 | back (under the name of internal_relocs). */ |
| 1120 | |
| 1121 | return internal_relocs; |
| 1122 | |
| 1123 | error_return: |
| 1124 | if (alloc1 != NULL) |
| 1125 | free (alloc1); |
| 1126 | if (alloc2 != NULL) |
| 1127 | free (alloc2); |
| 1128 | return NULL; |
| 1129 | } |
| 1130 | |
| 1131 | /* Record an assignment to a symbol made by a linker script. We need |
| 1132 | this in case some dynamic object refers to this symbol. */ |
| 1133 | |
| 1134 | /*ARGSUSED*/ |
| 1135 | boolean |
| 1136 | NAME(bfd_elf,record_link_assignment) (output_bfd, info, name, provide) |
| 1137 | bfd *output_bfd; |
| 1138 | struct bfd_link_info *info; |
| 1139 | const char *name; |
| 1140 | boolean provide; |
| 1141 | { |
| 1142 | struct elf_link_hash_entry *h; |
| 1143 | |
| 1144 | if (info->hash->creator->flavour != bfd_target_elf_flavour) |
| 1145 | return true; |
| 1146 | |
| 1147 | h = elf_link_hash_lookup (elf_hash_table (info), name, true, true, false); |
| 1148 | if (h == NULL) |
| 1149 | return false; |
| 1150 | |
| 1151 | /* If this symbol is being provided by the linker script, and it is |
| 1152 | currently defined by a dynamic object, but not by a regular |
| 1153 | object, then mark it as undefined so that the generic linker will |
| 1154 | force the correct value. */ |
| 1155 | if (provide |
| 1156 | && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 |
| 1157 | && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0) |
| 1158 | h->root.type = bfd_link_hash_undefined; |
| 1159 | |
| 1160 | h->elf_link_hash_flags |= ELF_LINK_HASH_DEF_REGULAR; |
| 1161 | h->type = STT_OBJECT; |
| 1162 | |
| 1163 | if (((h->elf_link_hash_flags & (ELF_LINK_HASH_DEF_DYNAMIC |
| 1164 | | ELF_LINK_HASH_REF_DYNAMIC)) != 0 |
| 1165 | || info->shared) |
| 1166 | && h->dynindx == -1) |
| 1167 | { |
| 1168 | if (! _bfd_elf_link_record_dynamic_symbol (info, h)) |
| 1169 | return false; |
| 1170 | |
| 1171 | /* If this is a weak defined symbol, and we know a corresponding |
| 1172 | real symbol from the same dynamic object, make sure the real |
| 1173 | symbol is also made into a dynamic symbol. */ |
| 1174 | if (h->weakdef != NULL |
| 1175 | && h->weakdef->dynindx == -1) |
| 1176 | { |
| 1177 | if (! _bfd_elf_link_record_dynamic_symbol (info, h->weakdef)) |
| 1178 | return false; |
| 1179 | } |
| 1180 | } |
| 1181 | |
| 1182 | return true; |
| 1183 | } |
| 1184 | |
| 1185 | /* Array used to determine the number of hash table buckets to use |
| 1186 | based on the number of symbols there are. If there are fewer than |
| 1187 | 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets, |
| 1188 | fewer than 37 we use 17 buckets, and so forth. We never use more |
| 1189 | than 521 buckets. */ |
| 1190 | |
| 1191 | static const size_t elf_buckets[] = |
| 1192 | { |
| 1193 | 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 0 |
| 1194 | }; |
| 1195 | |
| 1196 | /* Set up the sizes and contents of the ELF dynamic sections. This is |
| 1197 | called by the ELF linker emulation before_allocation routine. We |
| 1198 | must set the sizes of the sections before the linker sets the |
| 1199 | addresses of the various sections. */ |
| 1200 | |
| 1201 | boolean |
| 1202 | NAME(bfd_elf,size_dynamic_sections) (output_bfd, soname, rpath, |
| 1203 | export_dynamic, info, sinterpptr) |
| 1204 | bfd *output_bfd; |
| 1205 | const char *soname; |
| 1206 | const char *rpath; |
| 1207 | boolean export_dynamic; |
| 1208 | struct bfd_link_info *info; |
| 1209 | asection **sinterpptr; |
| 1210 | { |
| 1211 | bfd *dynobj; |
| 1212 | struct elf_backend_data *bed; |
| 1213 | |
| 1214 | *sinterpptr = NULL; |
| 1215 | |
| 1216 | if (info->hash->creator->flavour != bfd_target_elf_flavour) |
| 1217 | return true; |
| 1218 | |
| 1219 | dynobj = elf_hash_table (info)->dynobj; |
| 1220 | |
| 1221 | /* If there were no dynamic objects in the link, there is nothing to |
| 1222 | do here. */ |
| 1223 | if (dynobj == NULL) |
| 1224 | return true; |
| 1225 | |
| 1226 | /* If we are supposed to export all symbols into the dynamic symbol |
| 1227 | table (this is not the normal case), then do so. */ |
| 1228 | if (export_dynamic) |
| 1229 | { |
| 1230 | struct elf_info_failed eif; |
| 1231 | |
| 1232 | eif.failed = false; |
| 1233 | eif.info = info; |
| 1234 | elf_link_hash_traverse (elf_hash_table (info), elf_export_symbol, |
| 1235 | (PTR) &eif); |
| 1236 | if (eif.failed) |
| 1237 | return false; |
| 1238 | } |
| 1239 | |
| 1240 | if (elf_hash_table (info)->dynamic_sections_created) |
| 1241 | { |
| 1242 | struct elf_info_failed eif; |
| 1243 | bfd_size_type strsize; |
| 1244 | |
| 1245 | *sinterpptr = bfd_get_section_by_name (dynobj, ".interp"); |
| 1246 | BFD_ASSERT (*sinterpptr != NULL || info->shared); |
| 1247 | |
| 1248 | if (soname != NULL) |
| 1249 | { |
| 1250 | bfd_size_type indx; |
| 1251 | |
| 1252 | indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, soname, |
| 1253 | true, true); |
| 1254 | if (indx == (bfd_size_type) -1 |
| 1255 | || ! elf_add_dynamic_entry (info, DT_SONAME, indx)) |
| 1256 | return false; |
| 1257 | } |
| 1258 | |
| 1259 | if (info->symbolic) |
| 1260 | { |
| 1261 | if (! elf_add_dynamic_entry (info, DT_SYMBOLIC, 0)) |
| 1262 | return false; |
| 1263 | } |
| 1264 | |
| 1265 | if (rpath != NULL) |
| 1266 | { |
| 1267 | bfd_size_type indx; |
| 1268 | |
| 1269 | indx = _bfd_stringtab_add (elf_hash_table (info)->dynstr, rpath, |
| 1270 | true, true); |
| 1271 | if (indx == (bfd_size_type) -1 |
| 1272 | || ! elf_add_dynamic_entry (info, DT_RPATH, indx)) |
| 1273 | return false; |
| 1274 | } |
| 1275 | |
| 1276 | /* Find all symbols which were defined in a dynamic object and make |
| 1277 | the backend pick a reasonable value for them. */ |
| 1278 | eif.failed = false; |
| 1279 | eif.info = info; |
| 1280 | elf_link_hash_traverse (elf_hash_table (info), |
| 1281 | elf_adjust_dynamic_symbol, |
| 1282 | (PTR) &eif); |
| 1283 | if (eif.failed) |
| 1284 | return false; |
| 1285 | |
| 1286 | /* Add some entries to the .dynamic section. We fill in some of the |
| 1287 | values later, in elf_bfd_final_link, but we must add the entries |
| 1288 | now so that we know the final size of the .dynamic section. */ |
| 1289 | if (elf_link_hash_lookup (elf_hash_table (info), "_init", false, |
| 1290 | false, false) != NULL) |
| 1291 | { |
| 1292 | if (! elf_add_dynamic_entry (info, DT_INIT, 0)) |
| 1293 | return false; |
| 1294 | } |
| 1295 | if (elf_link_hash_lookup (elf_hash_table (info), "_fini", false, |
| 1296 | false, false) != NULL) |
| 1297 | { |
| 1298 | if (! elf_add_dynamic_entry (info, DT_FINI, 0)) |
| 1299 | return false; |
| 1300 | } |
| 1301 | strsize = _bfd_stringtab_size (elf_hash_table (info)->dynstr); |
| 1302 | if (! elf_add_dynamic_entry (info, DT_HASH, 0) |
| 1303 | || ! elf_add_dynamic_entry (info, DT_STRTAB, 0) |
| 1304 | || ! elf_add_dynamic_entry (info, DT_SYMTAB, 0) |
| 1305 | || ! elf_add_dynamic_entry (info, DT_STRSZ, strsize) |
| 1306 | || ! elf_add_dynamic_entry (info, DT_SYMENT, |
| 1307 | sizeof (Elf_External_Sym))) |
| 1308 | return false; |
| 1309 | } |
| 1310 | |
| 1311 | /* The backend must work out the sizes of all the other dynamic |
| 1312 | sections. */ |
| 1313 | bed = get_elf_backend_data (output_bfd); |
| 1314 | if (! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info)) |
| 1315 | return false; |
| 1316 | |
| 1317 | if (elf_hash_table (info)->dynamic_sections_created) |
| 1318 | { |
| 1319 | size_t dynsymcount; |
| 1320 | asection *s; |
| 1321 | size_t i; |
| 1322 | size_t bucketcount = 0; |
| 1323 | Elf_Internal_Sym isym; |
| 1324 | |
| 1325 | /* Set the size of the .dynsym and .hash sections. We counted |
| 1326 | the number of dynamic symbols in elf_link_add_object_symbols. |
| 1327 | We will build the contents of .dynsym and .hash when we build |
| 1328 | the final symbol table, because until then we do not know the |
| 1329 | correct value to give the symbols. We built the .dynstr |
| 1330 | section as we went along in elf_link_add_object_symbols. */ |
| 1331 | dynsymcount = elf_hash_table (info)->dynsymcount; |
| 1332 | s = bfd_get_section_by_name (dynobj, ".dynsym"); |
| 1333 | BFD_ASSERT (s != NULL); |
| 1334 | s->_raw_size = dynsymcount * sizeof (Elf_External_Sym); |
| 1335 | s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size); |
| 1336 | if (s->contents == NULL && s->_raw_size != 0) |
| 1337 | { |
| 1338 | bfd_set_error (bfd_error_no_memory); |
| 1339 | return false; |
| 1340 | } |
| 1341 | |
| 1342 | /* The first entry in .dynsym is a dummy symbol. */ |
| 1343 | isym.st_value = 0; |
| 1344 | isym.st_size = 0; |
| 1345 | isym.st_name = 0; |
| 1346 | isym.st_info = 0; |
| 1347 | isym.st_other = 0; |
| 1348 | isym.st_shndx = 0; |
| 1349 | elf_swap_symbol_out (output_bfd, &isym, |
| 1350 | (PTR) (Elf_External_Sym *) s->contents); |
| 1351 | |
| 1352 | for (i = 0; elf_buckets[i] != 0; i++) |
| 1353 | { |
| 1354 | bucketcount = elf_buckets[i]; |
| 1355 | if (dynsymcount < elf_buckets[i + 1]) |
| 1356 | break; |
| 1357 | } |
| 1358 | |
| 1359 | s = bfd_get_section_by_name (dynobj, ".hash"); |
| 1360 | BFD_ASSERT (s != NULL); |
| 1361 | s->_raw_size = (2 + bucketcount + dynsymcount) * (ARCH_SIZE / 8); |
| 1362 | s->contents = (bfd_byte *) bfd_alloc (output_bfd, s->_raw_size); |
| 1363 | if (s->contents == NULL) |
| 1364 | { |
| 1365 | bfd_set_error (bfd_error_no_memory); |
| 1366 | return false; |
| 1367 | } |
| 1368 | memset (s->contents, 0, (size_t) s->_raw_size); |
| 1369 | |
| 1370 | put_word (output_bfd, bucketcount, s->contents); |
| 1371 | put_word (output_bfd, dynsymcount, s->contents + (ARCH_SIZE / 8)); |
| 1372 | |
| 1373 | elf_hash_table (info)->bucketcount = bucketcount; |
| 1374 | |
| 1375 | s = bfd_get_section_by_name (dynobj, ".dynstr"); |
| 1376 | BFD_ASSERT (s != NULL); |
| 1377 | s->_raw_size = _bfd_stringtab_size (elf_hash_table (info)->dynstr); |
| 1378 | |
| 1379 | if (! elf_add_dynamic_entry (info, DT_NULL, 0)) |
| 1380 | return false; |
| 1381 | } |
| 1382 | |
| 1383 | return true; |
| 1384 | } |
| 1385 | |
| 1386 | /* This routine is used to export all defined symbols into the dynamic |
| 1387 | symbol table. It is called via elf_link_hash_traverse. */ |
| 1388 | |
| 1389 | static boolean |
| 1390 | elf_export_symbol (h, data) |
| 1391 | struct elf_link_hash_entry *h; |
| 1392 | PTR data; |
| 1393 | { |
| 1394 | struct elf_info_failed *eif = (struct elf_info_failed *) data; |
| 1395 | |
| 1396 | if (h->dynindx == -1 |
| 1397 | && (h->elf_link_hash_flags |
| 1398 | & (ELF_LINK_HASH_DEF_REGULAR | ELF_LINK_HASH_REF_REGULAR)) != 0) |
| 1399 | { |
| 1400 | if (! _bfd_elf_link_record_dynamic_symbol (eif->info, h)) |
| 1401 | { |
| 1402 | eif->failed = true; |
| 1403 | return false; |
| 1404 | } |
| 1405 | } |
| 1406 | |
| 1407 | return true; |
| 1408 | } |
| 1409 | |
| 1410 | /* Make the backend pick a good value for a dynamic symbol. This is |
| 1411 | called via elf_link_hash_traverse, and also calls itself |
| 1412 | recursively. */ |
| 1413 | |
| 1414 | static boolean |
| 1415 | elf_adjust_dynamic_symbol (h, data) |
| 1416 | struct elf_link_hash_entry *h; |
| 1417 | PTR data; |
| 1418 | { |
| 1419 | struct elf_info_failed *eif = (struct elf_info_failed *) data; |
| 1420 | bfd *dynobj; |
| 1421 | struct elf_backend_data *bed; |
| 1422 | |
| 1423 | /* If -Bsymbolic was used (which means to bind references to global |
| 1424 | symbols to the definition within the shared object), and this |
| 1425 | symbol was defined in a regular object, then it actually doesn't |
| 1426 | need a PLT entry. */ |
| 1427 | if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0 |
| 1428 | && eif->info->shared |
| 1429 | && eif->info->symbolic |
| 1430 | && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0) |
| 1431 | h->elf_link_hash_flags &=~ ELF_LINK_HASH_NEEDS_PLT; |
| 1432 | |
| 1433 | /* If this symbol does not require a PLT entry, and it is not |
| 1434 | defined by a dynamic object, or is not referenced by a regular |
| 1435 | object, ignore it. FIXME: Do we need to worry about symbols |
| 1436 | which are defined by one dynamic object and referenced by another |
| 1437 | one? */ |
| 1438 | if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) == 0 |
| 1439 | && ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0 |
| 1440 | || (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) == 0 |
| 1441 | || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0)) |
| 1442 | return true; |
| 1443 | |
| 1444 | /* If we've already adjusted this symbol, don't do it again. This |
| 1445 | can happen via a recursive call. */ |
| 1446 | if ((h->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0) |
| 1447 | return true; |
| 1448 | |
| 1449 | /* Don't look at this symbol again. Note that we must set this |
| 1450 | after checking the above conditions, because we may look at a |
| 1451 | symbol once, decide not to do anything, and then get called |
| 1452 | recursively later after REF_REGULAR is set below. */ |
| 1453 | h->elf_link_hash_flags |= ELF_LINK_HASH_DYNAMIC_ADJUSTED; |
| 1454 | |
| 1455 | /* If this is a weak definition, and we know a real definition, and |
| 1456 | the real symbol is not itself defined by a regular object file, |
| 1457 | then get a good value for the real definition. We handle the |
| 1458 | real symbol first, for the convenience of the backend routine. |
| 1459 | |
| 1460 | Note that there is a confusing case here. If the real definition |
| 1461 | is defined by a regular object file, we don't get the real symbol |
| 1462 | from the dynamic object, but we do get the weak symbol. If the |
| 1463 | processor backend uses a COPY reloc, then if some routine in the |
| 1464 | dynamic object changes the real symbol, we will not see that |
| 1465 | change in the corresponding weak symbol. This is the way other |
| 1466 | ELF linkers work as well, and seems to be a result of the shared |
| 1467 | library model. |
| 1468 | |
| 1469 | I will clarify this issue. Most SVR4 shared libraries define the |
| 1470 | variable _timezone and define timezone as a weak synonym. The |
| 1471 | tzset call changes _timezone. If you write |
| 1472 | extern int timezone; |
| 1473 | int _timezone = 5; |
| 1474 | int main () { tzset (); printf ("%d %d\n", timezone, _timezone); } |
| 1475 | you might expect that, since timezone is a synonym for _timezone, |
| 1476 | the same number will print both times. However, if the processor |
| 1477 | backend uses a COPY reloc, then actually timezone will be copied |
| 1478 | into your process image, and, since you define _timezone |
| 1479 | yourself, _timezone will not. Thus timezone and _timezone will |
| 1480 | wind up at different memory locations. The tzset call will set |
| 1481 | _timezone, leaving timezone unchanged. */ |
| 1482 | |
| 1483 | if (h->weakdef != NULL) |
| 1484 | { |
| 1485 | struct elf_link_hash_entry *weakdef; |
| 1486 | |
| 1487 | BFD_ASSERT (h->root.type == bfd_link_hash_defined |
| 1488 | || h->root.type == bfd_link_hash_defweak); |
| 1489 | weakdef = h->weakdef; |
| 1490 | BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined |
| 1491 | || weakdef->root.type == bfd_link_hash_defweak); |
| 1492 | BFD_ASSERT (weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC); |
| 1493 | if ((weakdef->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) != 0) |
| 1494 | { |
| 1495 | /* This symbol is defined by a regular object file, so we |
| 1496 | will not do anything special. Clear weakdef for the |
| 1497 | convenience of the processor backend. */ |
| 1498 | h->weakdef = NULL; |
| 1499 | } |
| 1500 | else |
| 1501 | { |
| 1502 | /* There is an implicit reference by a regular object file |
| 1503 | via the weak symbol. */ |
| 1504 | weakdef->elf_link_hash_flags |= ELF_LINK_HASH_REF_REGULAR; |
| 1505 | if (! elf_adjust_dynamic_symbol (weakdef, (PTR) eif)) |
| 1506 | return false; |
| 1507 | } |
| 1508 | } |
| 1509 | |
| 1510 | dynobj = elf_hash_table (eif->info)->dynobj; |
| 1511 | bed = get_elf_backend_data (dynobj); |
| 1512 | if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h)) |
| 1513 | { |
| 1514 | eif->failed = true; |
| 1515 | return false; |
| 1516 | } |
| 1517 | |
| 1518 | return true; |
| 1519 | } |
| 1520 | \f |
| 1521 | /* Final phase of ELF linker. */ |
| 1522 | |
| 1523 | /* A structure we use to avoid passing large numbers of arguments. */ |
| 1524 | |
| 1525 | struct elf_final_link_info |
| 1526 | { |
| 1527 | /* General link information. */ |
| 1528 | struct bfd_link_info *info; |
| 1529 | /* Output BFD. */ |
| 1530 | bfd *output_bfd; |
| 1531 | /* Symbol string table. */ |
| 1532 | struct bfd_strtab_hash *symstrtab; |
| 1533 | /* .dynsym section. */ |
| 1534 | asection *dynsym_sec; |
| 1535 | /* .hash section. */ |
| 1536 | asection *hash_sec; |
| 1537 | /* Buffer large enough to hold contents of any section. */ |
| 1538 | bfd_byte *contents; |
| 1539 | /* Buffer large enough to hold external relocs of any section. */ |
| 1540 | PTR external_relocs; |
| 1541 | /* Buffer large enough to hold internal relocs of any section. */ |
| 1542 | Elf_Internal_Rela *internal_relocs; |
| 1543 | /* Buffer large enough to hold external local symbols of any input |
| 1544 | BFD. */ |
| 1545 | Elf_External_Sym *external_syms; |
| 1546 | /* Buffer large enough to hold internal local symbols of any input |
| 1547 | BFD. */ |
| 1548 | Elf_Internal_Sym *internal_syms; |
| 1549 | /* Array large enough to hold a symbol index for each local symbol |
| 1550 | of any input BFD. */ |
| 1551 | long *indices; |
| 1552 | /* Array large enough to hold a section pointer for each local |
| 1553 | symbol of any input BFD. */ |
| 1554 | asection **sections; |
| 1555 | /* Buffer to hold swapped out symbols. */ |
| 1556 | Elf_External_Sym *symbuf; |
| 1557 | /* Number of swapped out symbols in buffer. */ |
| 1558 | size_t symbuf_count; |
| 1559 | /* Number of symbols which fit in symbuf. */ |
| 1560 | size_t symbuf_size; |
| 1561 | }; |
| 1562 | |
| 1563 | static boolean elf_link_output_sym |
| 1564 | PARAMS ((struct elf_final_link_info *, const char *, |
| 1565 | Elf_Internal_Sym *, asection *)); |
| 1566 | static boolean elf_link_flush_output_syms |
| 1567 | PARAMS ((struct elf_final_link_info *)); |
| 1568 | static boolean elf_link_output_extsym |
| 1569 | PARAMS ((struct elf_link_hash_entry *, PTR)); |
| 1570 | static boolean elf_link_input_bfd |
| 1571 | PARAMS ((struct elf_final_link_info *, bfd *)); |
| 1572 | static boolean elf_reloc_link_order |
| 1573 | PARAMS ((bfd *, struct bfd_link_info *, asection *, |
| 1574 | struct bfd_link_order *)); |
| 1575 | |
| 1576 | /* This struct is used to pass information to routines called via |
| 1577 | elf_link_hash_traverse which must return failure. */ |
| 1578 | |
| 1579 | struct elf_finfo_failed |
| 1580 | { |
| 1581 | boolean failed; |
| 1582 | struct elf_final_link_info *finfo; |
| 1583 | }; |
| 1584 | |
| 1585 | /* Do the final step of an ELF link. */ |
| 1586 | |
| 1587 | boolean |
| 1588 | elf_bfd_final_link (abfd, info) |
| 1589 | bfd *abfd; |
| 1590 | struct bfd_link_info *info; |
| 1591 | { |
| 1592 | boolean dynamic; |
| 1593 | bfd *dynobj; |
| 1594 | struct elf_final_link_info finfo; |
| 1595 | register asection *o; |
| 1596 | register struct bfd_link_order *p; |
| 1597 | register bfd *sub; |
| 1598 | size_t max_contents_size; |
| 1599 | size_t max_external_reloc_size; |
| 1600 | size_t max_internal_reloc_count; |
| 1601 | size_t max_sym_count; |
| 1602 | file_ptr off; |
| 1603 | Elf_Internal_Sym elfsym; |
| 1604 | unsigned int i; |
| 1605 | Elf_Internal_Shdr *symtab_hdr; |
| 1606 | Elf_Internal_Shdr *symstrtab_hdr; |
| 1607 | struct elf_backend_data *bed = get_elf_backend_data (abfd); |
| 1608 | struct elf_finfo_failed eif; |
| 1609 | |
| 1610 | if (info->shared) |
| 1611 | abfd->flags |= DYNAMIC; |
| 1612 | |
| 1613 | dynamic = elf_hash_table (info)->dynamic_sections_created; |
| 1614 | dynobj = elf_hash_table (info)->dynobj; |
| 1615 | |
| 1616 | finfo.info = info; |
| 1617 | finfo.output_bfd = abfd; |
| 1618 | finfo.symstrtab = elf_stringtab_init (); |
| 1619 | if (finfo.symstrtab == NULL) |
| 1620 | return false; |
| 1621 | if (! dynamic) |
| 1622 | { |
| 1623 | finfo.dynsym_sec = NULL; |
| 1624 | finfo.hash_sec = NULL; |
| 1625 | } |
| 1626 | else |
| 1627 | { |
| 1628 | finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym"); |
| 1629 | finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash"); |
| 1630 | BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL); |
| 1631 | } |
| 1632 | finfo.contents = NULL; |
| 1633 | finfo.external_relocs = NULL; |
| 1634 | finfo.internal_relocs = NULL; |
| 1635 | finfo.external_syms = NULL; |
| 1636 | finfo.internal_syms = NULL; |
| 1637 | finfo.indices = NULL; |
| 1638 | finfo.sections = NULL; |
| 1639 | finfo.symbuf = NULL; |
| 1640 | finfo.symbuf_count = 0; |
| 1641 | |
| 1642 | /* Count up the number of relocations we will output for each output |
| 1643 | section, so that we know the sizes of the reloc sections. We |
| 1644 | also figure out some maximum sizes. */ |
| 1645 | max_contents_size = 0; |
| 1646 | max_external_reloc_size = 0; |
| 1647 | max_internal_reloc_count = 0; |
| 1648 | max_sym_count = 0; |
| 1649 | for (o = abfd->sections; o != (asection *) NULL; o = o->next) |
| 1650 | { |
| 1651 | o->reloc_count = 0; |
| 1652 | |
| 1653 | for (p = o->link_order_head; p != NULL; p = p->next) |
| 1654 | { |
| 1655 | if (p->type == bfd_section_reloc_link_order |
| 1656 | || p->type == bfd_symbol_reloc_link_order) |
| 1657 | ++o->reloc_count; |
| 1658 | else if (p->type == bfd_indirect_link_order) |
| 1659 | { |
| 1660 | asection *sec; |
| 1661 | |
| 1662 | sec = p->u.indirect.section; |
| 1663 | |
| 1664 | if (info->relocateable) |
| 1665 | o->reloc_count += sec->reloc_count; |
| 1666 | |
| 1667 | if (sec->_raw_size > max_contents_size) |
| 1668 | max_contents_size = sec->_raw_size; |
| 1669 | if (sec->_cooked_size > max_contents_size) |
| 1670 | max_contents_size = sec->_cooked_size; |
| 1671 | |
| 1672 | /* We are interested in just local symbols, not all |
| 1673 | symbols. */ |
| 1674 | if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour) |
| 1675 | { |
| 1676 | size_t sym_count; |
| 1677 | |
| 1678 | if (elf_bad_symtab (sec->owner)) |
| 1679 | sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size |
| 1680 | / sizeof (Elf_External_Sym)); |
| 1681 | else |
| 1682 | sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info; |
| 1683 | |
| 1684 | if (sym_count > max_sym_count) |
| 1685 | max_sym_count = sym_count; |
| 1686 | |
| 1687 | if ((sec->flags & SEC_RELOC) != 0) |
| 1688 | { |
| 1689 | size_t ext_size; |
| 1690 | |
| 1691 | ext_size = elf_section_data (sec)->rel_hdr.sh_size; |
| 1692 | if (ext_size > max_external_reloc_size) |
| 1693 | max_external_reloc_size = ext_size; |
| 1694 | if (sec->reloc_count > max_internal_reloc_count) |
| 1695 | max_internal_reloc_count = sec->reloc_count; |
| 1696 | } |
| 1697 | } |
| 1698 | } |
| 1699 | } |
| 1700 | |
| 1701 | if (o->reloc_count > 0) |
| 1702 | o->flags |= SEC_RELOC; |
| 1703 | else |
| 1704 | { |
| 1705 | /* Explicitly clear the SEC_RELOC flag. The linker tends to |
| 1706 | set it (this is probably a bug) and if it is set |
| 1707 | assign_section_numbers will create a reloc section. */ |
| 1708 | o->flags &=~ SEC_RELOC; |
| 1709 | } |
| 1710 | |
| 1711 | /* If the SEC_ALLOC flag is not set, force the section VMA to |
| 1712 | zero. This is done in elf_fake_sections as well, but forcing |
| 1713 | the VMA to 0 here will ensure that relocs against these |
| 1714 | sections are handled correctly. */ |
| 1715 | if ((o->flags & SEC_ALLOC) == 0) |
| 1716 | o->vma = 0; |
| 1717 | } |
| 1718 | |
| 1719 | /* Figure out the file positions for everything but the symbol table |
| 1720 | and the relocs. We set symcount to force assign_section_numbers |
| 1721 | to create a symbol table. */ |
| 1722 | abfd->symcount = info->strip == strip_all ? 0 : 1; |
| 1723 | BFD_ASSERT (! abfd->output_has_begun); |
| 1724 | if (! _bfd_elf_compute_section_file_positions (abfd, info)) |
| 1725 | goto error_return; |
| 1726 | |
| 1727 | /* That created the reloc sections. Set their sizes, and assign |
| 1728 | them file positions, and allocate some buffers. */ |
| 1729 | for (o = abfd->sections; o != NULL; o = o->next) |
| 1730 | { |
| 1731 | if ((o->flags & SEC_RELOC) != 0) |
| 1732 | { |
| 1733 | Elf_Internal_Shdr *rel_hdr; |
| 1734 | register struct elf_link_hash_entry **p, **pend; |
| 1735 | |
| 1736 | rel_hdr = &elf_section_data (o)->rel_hdr; |
| 1737 | |
| 1738 | rel_hdr->sh_size = rel_hdr->sh_entsize * o->reloc_count; |
| 1739 | |
| 1740 | /* The contents field must last into write_object_contents, |
| 1741 | so we allocate it with bfd_alloc rather than malloc. */ |
| 1742 | rel_hdr->contents = (PTR) bfd_alloc (abfd, rel_hdr->sh_size); |
| 1743 | if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0) |
| 1744 | { |
| 1745 | bfd_set_error (bfd_error_no_memory); |
| 1746 | goto error_return; |
| 1747 | } |
| 1748 | |
| 1749 | p = ((struct elf_link_hash_entry **) |
| 1750 | malloc (o->reloc_count |
| 1751 | * sizeof (struct elf_link_hash_entry *))); |
| 1752 | if (p == NULL && o->reloc_count != 0) |
| 1753 | { |
| 1754 | bfd_set_error (bfd_error_no_memory); |
| 1755 | goto error_return; |
| 1756 | } |
| 1757 | elf_section_data (o)->rel_hashes = p; |
| 1758 | pend = p + o->reloc_count; |
| 1759 | for (; p < pend; p++) |
| 1760 | *p = NULL; |
| 1761 | |
| 1762 | /* Use the reloc_count field as an index when outputting the |
| 1763 | relocs. */ |
| 1764 | o->reloc_count = 0; |
| 1765 | } |
| 1766 | } |
| 1767 | |
| 1768 | _bfd_elf_assign_file_positions_for_relocs (abfd); |
| 1769 | |
| 1770 | /* We have now assigned file positions for all the sections except |
| 1771 | .symtab and .strtab. We start the .symtab section at the current |
| 1772 | file position, and write directly to it. We build the .strtab |
| 1773 | section in memory. When we add .dynsym support, we will build |
| 1774 | that in memory as well (.dynsym is smaller than .symtab). */ |
| 1775 | abfd->symcount = 0; |
| 1776 | symtab_hdr = &elf_tdata (abfd)->symtab_hdr; |
| 1777 | /* sh_name is set in prep_headers. */ |
| 1778 | symtab_hdr->sh_type = SHT_SYMTAB; |
| 1779 | symtab_hdr->sh_flags = 0; |
| 1780 | symtab_hdr->sh_addr = 0; |
| 1781 | symtab_hdr->sh_size = 0; |
| 1782 | symtab_hdr->sh_entsize = sizeof (Elf_External_Sym); |
| 1783 | /* sh_link is set in assign_section_numbers. */ |
| 1784 | /* sh_info is set below. */ |
| 1785 | /* sh_offset is set just below. */ |
| 1786 | symtab_hdr->sh_addralign = 4; /* FIXME: system dependent? */ |
| 1787 | |
| 1788 | off = elf_tdata (abfd)->next_file_pos; |
| 1789 | off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, true); |
| 1790 | |
| 1791 | /* Note that at this point elf_tdata (abfd)->next_file_pos is |
| 1792 | incorrect. We do not yet know the size of the .symtab section. |
| 1793 | We correct next_file_pos below, after we do know the size. */ |
| 1794 | |
| 1795 | /* Allocate a buffer to hold swapped out symbols. This is to avoid |
| 1796 | continuously seeking to the right position in the file. */ |
| 1797 | if (! info->keep_memory || max_sym_count < 20) |
| 1798 | finfo.symbuf_size = 20; |
| 1799 | else |
| 1800 | finfo.symbuf_size = max_sym_count; |
| 1801 | finfo.symbuf = ((Elf_External_Sym *) |
| 1802 | malloc (finfo.symbuf_size * sizeof (Elf_External_Sym))); |
| 1803 | if (finfo.symbuf == NULL) |
| 1804 | { |
| 1805 | bfd_set_error (bfd_error_no_memory); |
| 1806 | goto error_return; |
| 1807 | } |
| 1808 | |
| 1809 | /* Start writing out the symbol table. The first symbol is always a |
| 1810 | dummy symbol. */ |
| 1811 | elfsym.st_value = 0; |
| 1812 | elfsym.st_size = 0; |
| 1813 | elfsym.st_info = 0; |
| 1814 | elfsym.st_other = 0; |
| 1815 | elfsym.st_shndx = SHN_UNDEF; |
| 1816 | if (! elf_link_output_sym (&finfo, (const char *) NULL, |
| 1817 | &elfsym, bfd_und_section_ptr)) |
| 1818 | goto error_return; |
| 1819 | |
| 1820 | #if 0 |
| 1821 | /* Some standard ELF linkers do this, but we don't because it causes |
| 1822 | bootstrap comparison failures. */ |
| 1823 | /* Output a file symbol for the output file as the second symbol. |
| 1824 | We output this even if we are discarding local symbols, although |
| 1825 | I'm not sure if this is correct. */ |
| 1826 | elfsym.st_value = 0; |
| 1827 | elfsym.st_size = 0; |
| 1828 | elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_FILE); |
| 1829 | elfsym.st_other = 0; |
| 1830 | elfsym.st_shndx = SHN_ABS; |
| 1831 | if (! elf_link_output_sym (&finfo, bfd_get_filename (abfd), |
| 1832 | &elfsym, bfd_abs_section_ptr)) |
| 1833 | goto error_return; |
| 1834 | #endif |
| 1835 | |
| 1836 | /* Output a symbol for each section. We output these even if we are |
| 1837 | discarding local symbols, since they are used for relocs. These |
| 1838 | symbols have no names. We store the index of each one in the |
| 1839 | index field of the section, so that we can find it again when |
| 1840 | outputting relocs. */ |
| 1841 | elfsym.st_value = 0; |
| 1842 | elfsym.st_size = 0; |
| 1843 | elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION); |
| 1844 | elfsym.st_other = 0; |
| 1845 | for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++) |
| 1846 | { |
| 1847 | o = section_from_elf_index (abfd, i); |
| 1848 | if (o != NULL) |
| 1849 | o->target_index = abfd->symcount; |
| 1850 | elfsym.st_shndx = i; |
| 1851 | if (! elf_link_output_sym (&finfo, (const char *) NULL, |
| 1852 | &elfsym, o)) |
| 1853 | goto error_return; |
| 1854 | } |
| 1855 | |
| 1856 | /* Allocate some memory to hold information read in from the input |
| 1857 | files. */ |
| 1858 | finfo.contents = (bfd_byte *) malloc (max_contents_size); |
| 1859 | finfo.external_relocs = (PTR) malloc (max_external_reloc_size); |
| 1860 | finfo.internal_relocs = ((Elf_Internal_Rela *) |
| 1861 | malloc (max_internal_reloc_count |
| 1862 | * sizeof (Elf_Internal_Rela))); |
| 1863 | finfo.external_syms = ((Elf_External_Sym *) |
| 1864 | malloc (max_sym_count * sizeof (Elf_External_Sym))); |
| 1865 | finfo.internal_syms = ((Elf_Internal_Sym *) |
| 1866 | malloc (max_sym_count * sizeof (Elf_Internal_Sym))); |
| 1867 | finfo.indices = (long *) malloc (max_sym_count * sizeof (long)); |
| 1868 | finfo.sections = (asection **) malloc (max_sym_count * sizeof (asection *)); |
| 1869 | if ((finfo.contents == NULL && max_contents_size != 0) |
| 1870 | || (finfo.external_relocs == NULL && max_external_reloc_size != 0) |
| 1871 | || (finfo.internal_relocs == NULL && max_internal_reloc_count != 0) |
| 1872 | || (finfo.external_syms == NULL && max_sym_count != 0) |
| 1873 | || (finfo.internal_syms == NULL && max_sym_count != 0) |
| 1874 | || (finfo.indices == NULL && max_sym_count != 0) |
| 1875 | || (finfo.sections == NULL && max_sym_count != 0)) |
| 1876 | { |
| 1877 | bfd_set_error (bfd_error_no_memory); |
| 1878 | goto error_return; |
| 1879 | } |
| 1880 | |
| 1881 | /* Since ELF permits relocations to be against local symbols, we |
| 1882 | must have the local symbols available when we do the relocations. |
| 1883 | Since we would rather only read the local symbols once, and we |
| 1884 | would rather not keep them in memory, we handle all the |
| 1885 | relocations for a single input file at the same time. |
| 1886 | |
| 1887 | Unfortunately, there is no way to know the total number of local |
| 1888 | symbols until we have seen all of them, and the local symbol |
| 1889 | indices precede the global symbol indices. This means that when |
| 1890 | we are generating relocateable output, and we see a reloc against |
| 1891 | a global symbol, we can not know the symbol index until we have |
| 1892 | finished examining all the local symbols to see which ones we are |
| 1893 | going to output. To deal with this, we keep the relocations in |
| 1894 | memory, and don't output them until the end of the link. This is |
| 1895 | an unfortunate waste of memory, but I don't see a good way around |
| 1896 | it. Fortunately, it only happens when performing a relocateable |
| 1897 | link, which is not the common case. FIXME: If keep_memory is set |
| 1898 | we could write the relocs out and then read them again; I don't |
| 1899 | know how bad the memory loss will be. */ |
| 1900 | |
| 1901 | for (sub = info->input_bfds; sub != NULL; sub = sub->next) |
| 1902 | sub->output_has_begun = false; |
| 1903 | for (o = abfd->sections; o != NULL; o = o->next) |
| 1904 | { |
| 1905 | for (p = o->link_order_head; p != NULL; p = p->next) |
| 1906 | { |
| 1907 | if (p->type == bfd_indirect_link_order |
| 1908 | && (bfd_get_flavour (p->u.indirect.section->owner) |
| 1909 | == bfd_target_elf_flavour)) |
| 1910 | { |
| 1911 | sub = p->u.indirect.section->owner; |
| 1912 | if (! sub->output_has_begun) |
| 1913 | { |
| 1914 | if (! elf_link_input_bfd (&finfo, sub)) |
| 1915 | goto error_return; |
| 1916 | sub->output_has_begun = true; |
| 1917 | } |
| 1918 | } |
| 1919 | else if (p->type == bfd_section_reloc_link_order |
| 1920 | || p->type == bfd_symbol_reloc_link_order) |
| 1921 | { |
| 1922 | if (! elf_reloc_link_order (abfd, info, o, p)) |
| 1923 | goto error_return; |
| 1924 | } |
| 1925 | else |
| 1926 | { |
| 1927 | if (! _bfd_default_link_order (abfd, info, o, p)) |
| 1928 | goto error_return; |
| 1929 | } |
| 1930 | } |
| 1931 | } |
| 1932 | |
| 1933 | /* That wrote out all the local symbols. Finish up the symbol table |
| 1934 | with the global symbols. */ |
| 1935 | |
| 1936 | /* The sh_info field records the index of the first non local |
| 1937 | symbol. */ |
| 1938 | symtab_hdr->sh_info = abfd->symcount; |
| 1939 | if (dynamic) |
| 1940 | elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info = 1; |
| 1941 | |
| 1942 | /* We get the global symbols from the hash table. */ |
| 1943 | eif.failed = false; |
| 1944 | eif.finfo = &finfo; |
| 1945 | elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym, |
| 1946 | (PTR) &eif); |
| 1947 | if (eif.failed) |
| 1948 | return false; |
| 1949 | |
| 1950 | /* Flush all symbols to the file. */ |
| 1951 | if (! elf_link_flush_output_syms (&finfo)) |
| 1952 | return false; |
| 1953 | |
| 1954 | /* Now we know the size of the symtab section. */ |
| 1955 | off += symtab_hdr->sh_size; |
| 1956 | |
| 1957 | /* Finish up and write out the symbol string table (.strtab) |
| 1958 | section. */ |
| 1959 | symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr; |
| 1960 | /* sh_name was set in prep_headers. */ |
| 1961 | symstrtab_hdr->sh_type = SHT_STRTAB; |
| 1962 | symstrtab_hdr->sh_flags = 0; |
| 1963 | symstrtab_hdr->sh_addr = 0; |
| 1964 | symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab); |
| 1965 | symstrtab_hdr->sh_entsize = 0; |
| 1966 | symstrtab_hdr->sh_link = 0; |
| 1967 | symstrtab_hdr->sh_info = 0; |
| 1968 | /* sh_offset is set just below. */ |
| 1969 | symstrtab_hdr->sh_addralign = 1; |
| 1970 | |
| 1971 | off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, true); |
| 1972 | elf_tdata (abfd)->next_file_pos = off; |
| 1973 | |
| 1974 | if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0 |
| 1975 | || ! _bfd_stringtab_emit (abfd, finfo.symstrtab)) |
| 1976 | return false; |
| 1977 | |
| 1978 | /* Adjust the relocs to have the correct symbol indices. */ |
| 1979 | for (o = abfd->sections; o != NULL; o = o->next) |
| 1980 | { |
| 1981 | struct elf_link_hash_entry **rel_hash; |
| 1982 | Elf_Internal_Shdr *rel_hdr; |
| 1983 | |
| 1984 | if ((o->flags & SEC_RELOC) == 0) |
| 1985 | continue; |
| 1986 | |
| 1987 | rel_hash = elf_section_data (o)->rel_hashes; |
| 1988 | rel_hdr = &elf_section_data (o)->rel_hdr; |
| 1989 | for (i = 0; i < o->reloc_count; i++, rel_hash++) |
| 1990 | { |
| 1991 | if (*rel_hash == NULL) |
| 1992 | continue; |
| 1993 | |
| 1994 | BFD_ASSERT ((*rel_hash)->indx >= 0); |
| 1995 | |
| 1996 | if (rel_hdr->sh_entsize == sizeof (Elf_External_Rel)) |
| 1997 | { |
| 1998 | Elf_External_Rel *erel; |
| 1999 | Elf_Internal_Rel irel; |
| 2000 | |
| 2001 | erel = (Elf_External_Rel *) rel_hdr->contents + i; |
| 2002 | elf_swap_reloc_in (abfd, erel, &irel); |
| 2003 | irel.r_info = ELF_R_INFO ((*rel_hash)->indx, |
| 2004 | ELF_R_TYPE (irel.r_info)); |
| 2005 | elf_swap_reloc_out (abfd, &irel, erel); |
| 2006 | } |
| 2007 | else |
| 2008 | { |
| 2009 | Elf_External_Rela *erela; |
| 2010 | Elf_Internal_Rela irela; |
| 2011 | |
| 2012 | BFD_ASSERT (rel_hdr->sh_entsize |
| 2013 | == sizeof (Elf_External_Rela)); |
| 2014 | |
| 2015 | erela = (Elf_External_Rela *) rel_hdr->contents + i; |
| 2016 | elf_swap_reloca_in (abfd, erela, &irela); |
| 2017 | irela.r_info = ELF_R_INFO ((*rel_hash)->indx, |
| 2018 | ELF_R_TYPE (irela.r_info)); |
| 2019 | elf_swap_reloca_out (abfd, &irela, erela); |
| 2020 | } |
| 2021 | } |
| 2022 | |
| 2023 | /* Set the reloc_count field to 0 to prevent write_relocs from |
| 2024 | trying to swap the relocs out itself. */ |
| 2025 | o->reloc_count = 0; |
| 2026 | } |
| 2027 | |
| 2028 | /* If we are linking against a dynamic object, or generating a |
| 2029 | shared library, finish up the dynamic linking information. */ |
| 2030 | if (dynamic) |
| 2031 | { |
| 2032 | Elf_External_Dyn *dyncon, *dynconend; |
| 2033 | |
| 2034 | /* Fix up .dynamic entries. */ |
| 2035 | o = bfd_get_section_by_name (dynobj, ".dynamic"); |
| 2036 | BFD_ASSERT (o != NULL); |
| 2037 | |
| 2038 | dyncon = (Elf_External_Dyn *) o->contents; |
| 2039 | dynconend = (Elf_External_Dyn *) (o->contents + o->_raw_size); |
| 2040 | for (; dyncon < dynconend; dyncon++) |
| 2041 | { |
| 2042 | Elf_Internal_Dyn dyn; |
| 2043 | const char *name; |
| 2044 | unsigned int type; |
| 2045 | |
| 2046 | elf_swap_dyn_in (dynobj, dyncon, &dyn); |
| 2047 | |
| 2048 | switch (dyn.d_tag) |
| 2049 | { |
| 2050 | default: |
| 2051 | break; |
| 2052 | |
| 2053 | /* SVR4 linkers seem to set DT_INIT and DT_FINI based on |
| 2054 | magic _init and _fini symbols. This is pretty ugly, |
| 2055 | but we are compatible. */ |
| 2056 | case DT_INIT: |
| 2057 | name = "_init"; |
| 2058 | goto get_sym; |
| 2059 | case DT_FINI: |
| 2060 | name = "_fini"; |
| 2061 | get_sym: |
| 2062 | { |
| 2063 | struct elf_link_hash_entry *h; |
| 2064 | |
| 2065 | h = elf_link_hash_lookup (elf_hash_table (info), name, |
| 2066 | false, false, true); |
| 2067 | BFD_ASSERT (h != NULL); |
| 2068 | if (h->root.type == bfd_link_hash_defined |
| 2069 | || h->root.type == bfd_link_hash_defweak) |
| 2070 | { |
| 2071 | dyn.d_un.d_val = h->root.u.def.value; |
| 2072 | o = h->root.u.def.section; |
| 2073 | if (o->output_section != NULL) |
| 2074 | dyn.d_un.d_val += (o->output_section->vma |
| 2075 | + o->output_offset); |
| 2076 | else |
| 2077 | /* The symbol is imported from another shared |
| 2078 | library and does not apply to this one. */ |
| 2079 | dyn.d_un.d_val = 0; |
| 2080 | } |
| 2081 | elf_swap_dyn_out (dynobj, &dyn, dyncon); |
| 2082 | } |
| 2083 | break; |
| 2084 | |
| 2085 | case DT_HASH: |
| 2086 | name = ".hash"; |
| 2087 | goto get_vma; |
| 2088 | case DT_STRTAB: |
| 2089 | name = ".dynstr"; |
| 2090 | goto get_vma; |
| 2091 | case DT_SYMTAB: |
| 2092 | name = ".dynsym"; |
| 2093 | get_vma: |
| 2094 | o = bfd_get_section_by_name (abfd, name); |
| 2095 | BFD_ASSERT (o != NULL); |
| 2096 | dyn.d_un.d_ptr = o->vma; |
| 2097 | elf_swap_dyn_out (dynobj, &dyn, dyncon); |
| 2098 | break; |
| 2099 | |
| 2100 | case DT_REL: |
| 2101 | case DT_RELA: |
| 2102 | case DT_RELSZ: |
| 2103 | case DT_RELASZ: |
| 2104 | if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ) |
| 2105 | type = SHT_REL; |
| 2106 | else |
| 2107 | type = SHT_RELA; |
| 2108 | dyn.d_un.d_val = 0; |
| 2109 | for (i = 1; i < elf_elfheader (abfd)->e_shnum; i++) |
| 2110 | { |
| 2111 | Elf_Internal_Shdr *hdr; |
| 2112 | |
| 2113 | hdr = elf_elfsections (abfd)[i]; |
| 2114 | if (hdr->sh_type == type |
| 2115 | && (hdr->sh_flags & SHF_ALLOC) != 0) |
| 2116 | { |
| 2117 | if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ) |
| 2118 | dyn.d_un.d_val += hdr->sh_size; |
| 2119 | else |
| 2120 | { |
| 2121 | if (dyn.d_un.d_val == 0 |
| 2122 | || hdr->sh_addr < dyn.d_un.d_val) |
| 2123 | dyn.d_un.d_val = hdr->sh_addr; |
| 2124 | } |
| 2125 | } |
| 2126 | } |
| 2127 | elf_swap_dyn_out (dynobj, &dyn, dyncon); |
| 2128 | break; |
| 2129 | } |
| 2130 | } |
| 2131 | } |
| 2132 | |
| 2133 | /* If we have created any dynamic sections, then output them. */ |
| 2134 | if (dynobj != NULL) |
| 2135 | { |
| 2136 | if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info)) |
| 2137 | goto error_return; |
| 2138 | |
| 2139 | for (o = dynobj->sections; o != NULL; o = o->next) |
| 2140 | { |
| 2141 | if ((o->flags & SEC_HAS_CONTENTS) == 0 |
| 2142 | || o->_raw_size == 0) |
| 2143 | continue; |
| 2144 | if ((o->flags & SEC_IN_MEMORY) == 0) |
| 2145 | { |
| 2146 | /* At this point, we are only interested in sections |
| 2147 | created by elf_link_create_dynamic_sections. FIXME: |
| 2148 | This test is fragile. */ |
| 2149 | continue; |
| 2150 | } |
| 2151 | if ((elf_section_data (o->output_section)->this_hdr.sh_type |
| 2152 | != SHT_STRTAB) |
| 2153 | || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0) |
| 2154 | { |
| 2155 | if (! bfd_set_section_contents (abfd, o->output_section, |
| 2156 | o->contents, o->output_offset, |
| 2157 | o->_raw_size)) |
| 2158 | goto error_return; |
| 2159 | } |
| 2160 | else |
| 2161 | { |
| 2162 | file_ptr off; |
| 2163 | |
| 2164 | /* The contents of the .dynstr section are actually in a |
| 2165 | stringtab. */ |
| 2166 | off = elf_section_data (o->output_section)->this_hdr.sh_offset; |
| 2167 | if (bfd_seek (abfd, off, SEEK_SET) != 0 |
| 2168 | || ! _bfd_stringtab_emit (abfd, |
| 2169 | elf_hash_table (info)->dynstr)) |
| 2170 | goto error_return; |
| 2171 | } |
| 2172 | } |
| 2173 | } |
| 2174 | |
| 2175 | if (finfo.symstrtab != NULL) |
| 2176 | _bfd_stringtab_free (finfo.symstrtab); |
| 2177 | if (finfo.contents != NULL) |
| 2178 | free (finfo.contents); |
| 2179 | if (finfo.external_relocs != NULL) |
| 2180 | free (finfo.external_relocs); |
| 2181 | if (finfo.internal_relocs != NULL) |
| 2182 | free (finfo.internal_relocs); |
| 2183 | if (finfo.external_syms != NULL) |
| 2184 | free (finfo.external_syms); |
| 2185 | if (finfo.internal_syms != NULL) |
| 2186 | free (finfo.internal_syms); |
| 2187 | if (finfo.indices != NULL) |
| 2188 | free (finfo.indices); |
| 2189 | if (finfo.sections != NULL) |
| 2190 | free (finfo.sections); |
| 2191 | if (finfo.symbuf != NULL) |
| 2192 | free (finfo.symbuf); |
| 2193 | for (o = abfd->sections; o != NULL; o = o->next) |
| 2194 | { |
| 2195 | if ((o->flags & SEC_RELOC) != 0 |
| 2196 | && elf_section_data (o)->rel_hashes != NULL) |
| 2197 | free (elf_section_data (o)->rel_hashes); |
| 2198 | } |
| 2199 | |
| 2200 | elf_tdata (abfd)->linker = true; |
| 2201 | |
| 2202 | return true; |
| 2203 | |
| 2204 | error_return: |
| 2205 | if (finfo.symstrtab != NULL) |
| 2206 | _bfd_stringtab_free (finfo.symstrtab); |
| 2207 | if (finfo.contents != NULL) |
| 2208 | free (finfo.contents); |
| 2209 | if (finfo.external_relocs != NULL) |
| 2210 | free (finfo.external_relocs); |
| 2211 | if (finfo.internal_relocs != NULL) |
| 2212 | free (finfo.internal_relocs); |
| 2213 | if (finfo.external_syms != NULL) |
| 2214 | free (finfo.external_syms); |
| 2215 | if (finfo.internal_syms != NULL) |
| 2216 | free (finfo.internal_syms); |
| 2217 | if (finfo.indices != NULL) |
| 2218 | free (finfo.indices); |
| 2219 | if (finfo.sections != NULL) |
| 2220 | free (finfo.sections); |
| 2221 | if (finfo.symbuf != NULL) |
| 2222 | free (finfo.symbuf); |
| 2223 | for (o = abfd->sections; o != NULL; o = o->next) |
| 2224 | { |
| 2225 | if ((o->flags & SEC_RELOC) != 0 |
| 2226 | && elf_section_data (o)->rel_hashes != NULL) |
| 2227 | free (elf_section_data (o)->rel_hashes); |
| 2228 | } |
| 2229 | |
| 2230 | return false; |
| 2231 | } |
| 2232 | |
| 2233 | /* Add a symbol to the output symbol table. */ |
| 2234 | |
| 2235 | static boolean |
| 2236 | elf_link_output_sym (finfo, name, elfsym, input_sec) |
| 2237 | struct elf_final_link_info *finfo; |
| 2238 | const char *name; |
| 2239 | Elf_Internal_Sym *elfsym; |
| 2240 | asection *input_sec; |
| 2241 | { |
| 2242 | boolean (*output_symbol_hook) PARAMS ((bfd *, |
| 2243 | struct bfd_link_info *info, |
| 2244 | const char *, |
| 2245 | Elf_Internal_Sym *, |
| 2246 | asection *)); |
| 2247 | |
| 2248 | output_symbol_hook = get_elf_backend_data (finfo->output_bfd)-> |
| 2249 | elf_backend_link_output_symbol_hook; |
| 2250 | if (output_symbol_hook != NULL) |
| 2251 | { |
| 2252 | if (! ((*output_symbol_hook) |
| 2253 | (finfo->output_bfd, finfo->info, name, elfsym, input_sec))) |
| 2254 | return false; |
| 2255 | } |
| 2256 | |
| 2257 | if (name == (const char *) NULL || *name == '\0') |
| 2258 | elfsym->st_name = 0; |
| 2259 | else |
| 2260 | { |
| 2261 | elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab, |
| 2262 | name, true, |
| 2263 | false); |
| 2264 | if (elfsym->st_name == (unsigned long) -1) |
| 2265 | return false; |
| 2266 | } |
| 2267 | |
| 2268 | if (finfo->symbuf_count >= finfo->symbuf_size) |
| 2269 | { |
| 2270 | if (! elf_link_flush_output_syms (finfo)) |
| 2271 | return false; |
| 2272 | } |
| 2273 | |
| 2274 | elf_swap_symbol_out (finfo->output_bfd, elfsym, |
| 2275 | (PTR) (finfo->symbuf + finfo->symbuf_count)); |
| 2276 | ++finfo->symbuf_count; |
| 2277 | |
| 2278 | ++finfo->output_bfd->symcount; |
| 2279 | |
| 2280 | return true; |
| 2281 | } |
| 2282 | |
| 2283 | /* Flush the output symbols to the file. */ |
| 2284 | |
| 2285 | static boolean |
| 2286 | elf_link_flush_output_syms (finfo) |
| 2287 | struct elf_final_link_info *finfo; |
| 2288 | { |
| 2289 | Elf_Internal_Shdr *symtab; |
| 2290 | |
| 2291 | symtab = &elf_tdata (finfo->output_bfd)->symtab_hdr; |
| 2292 | |
| 2293 | if (bfd_seek (finfo->output_bfd, symtab->sh_offset + symtab->sh_size, |
| 2294 | SEEK_SET) != 0 |
| 2295 | || (bfd_write ((PTR) finfo->symbuf, finfo->symbuf_count, |
| 2296 | sizeof (Elf_External_Sym), finfo->output_bfd) |
| 2297 | != finfo->symbuf_count * sizeof (Elf_External_Sym))) |
| 2298 | return false; |
| 2299 | |
| 2300 | symtab->sh_size += finfo->symbuf_count * sizeof (Elf_External_Sym); |
| 2301 | |
| 2302 | finfo->symbuf_count = 0; |
| 2303 | |
| 2304 | return true; |
| 2305 | } |
| 2306 | |
| 2307 | /* Add an external symbol to the symbol table. This is called from |
| 2308 | the hash table traversal routine. */ |
| 2309 | |
| 2310 | static boolean |
| 2311 | elf_link_output_extsym (h, data) |
| 2312 | struct elf_link_hash_entry *h; |
| 2313 | PTR data; |
| 2314 | { |
| 2315 | struct elf_finfo_failed *eif = (struct elf_finfo_failed *) data; |
| 2316 | struct elf_final_link_info *finfo = eif->finfo; |
| 2317 | boolean strip; |
| 2318 | Elf_Internal_Sym sym; |
| 2319 | asection *input_sec; |
| 2320 | |
| 2321 | /* If we are not creating a shared library, and this symbol is |
| 2322 | referenced by a shared library but is not defined anywhere, then |
| 2323 | warn that it is undefined. If we do not do this, the runtime |
| 2324 | linker will complain that the symbol is undefined when the |
| 2325 | program is run. We don't have to worry about symbols that are |
| 2326 | referenced by regular files, because we will already have issued |
| 2327 | warnings for them. */ |
| 2328 | if (! finfo->info->relocateable |
| 2329 | && ! finfo->info->shared |
| 2330 | && h->root.type == bfd_link_hash_undefined |
| 2331 | && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0 |
| 2332 | && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0) |
| 2333 | { |
| 2334 | if (! ((*finfo->info->callbacks->undefined_symbol) |
| 2335 | (finfo->info, h->root.root.string, h->root.u.undef.abfd, |
| 2336 | (asection *) NULL, 0))) |
| 2337 | { |
| 2338 | eif->failed = true; |
| 2339 | return false; |
| 2340 | } |
| 2341 | } |
| 2342 | |
| 2343 | /* We don't want to output symbols that have never been mentioned by |
| 2344 | a regular file, or that we have been told to strip. However, if |
| 2345 | h->indx is set to -2, the symbol is used by a reloc and we must |
| 2346 | output it. */ |
| 2347 | if (h->indx == -2) |
| 2348 | strip = false; |
| 2349 | else if (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0 |
| 2350 | || (h->elf_link_hash_flags & ELF_LINK_HASH_REF_DYNAMIC) != 0) |
| 2351 | && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0 |
| 2352 | && (h->elf_link_hash_flags & ELF_LINK_HASH_REF_REGULAR) == 0) |
| 2353 | strip = true; |
| 2354 | else if (finfo->info->strip == strip_all |
| 2355 | || (finfo->info->strip == strip_some |
| 2356 | && bfd_hash_lookup (finfo->info->keep_hash, |
| 2357 | h->root.root.string, |
| 2358 | false, false) == NULL)) |
| 2359 | strip = true; |
| 2360 | else |
| 2361 | strip = false; |
| 2362 | |
| 2363 | /* If we're stripping it, and it's not a dynamic symbol, there's |
| 2364 | nothing else to do. */ |
| 2365 | if (strip && h->dynindx == -1) |
| 2366 | return true; |
| 2367 | |
| 2368 | sym.st_value = 0; |
| 2369 | sym.st_size = h->size; |
| 2370 | sym.st_other = 0; |
| 2371 | if (h->root.type == bfd_link_hash_undefweak |
| 2372 | || h->root.type == bfd_link_hash_defweak) |
| 2373 | sym.st_info = ELF_ST_INFO (STB_WEAK, h->type); |
| 2374 | else |
| 2375 | sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type); |
| 2376 | |
| 2377 | switch (h->root.type) |
| 2378 | { |
| 2379 | default: |
| 2380 | case bfd_link_hash_new: |
| 2381 | abort (); |
| 2382 | return false; |
| 2383 | |
| 2384 | case bfd_link_hash_undefined: |
| 2385 | input_sec = bfd_und_section_ptr; |
| 2386 | sym.st_shndx = SHN_UNDEF; |
| 2387 | break; |
| 2388 | |
| 2389 | case bfd_link_hash_undefweak: |
| 2390 | input_sec = bfd_und_section_ptr; |
| 2391 | sym.st_shndx = SHN_UNDEF; |
| 2392 | break; |
| 2393 | |
| 2394 | case bfd_link_hash_defined: |
| 2395 | case bfd_link_hash_defweak: |
| 2396 | { |
| 2397 | input_sec = h->root.u.def.section; |
| 2398 | if (input_sec->output_section != NULL) |
| 2399 | { |
| 2400 | sym.st_shndx = |
| 2401 | _bfd_elf_section_from_bfd_section (finfo->output_bfd, |
| 2402 | input_sec->output_section); |
| 2403 | if (sym.st_shndx == (unsigned short) -1) |
| 2404 | { |
| 2405 | eif->failed = true; |
| 2406 | return false; |
| 2407 | } |
| 2408 | |
| 2409 | /* ELF symbols in relocateable files are section relative, |
| 2410 | but in nonrelocateable files they are virtual |
| 2411 | addresses. */ |
| 2412 | sym.st_value = h->root.u.def.value + input_sec->output_offset; |
| 2413 | if (! finfo->info->relocateable) |
| 2414 | sym.st_value += input_sec->output_section->vma; |
| 2415 | } |
| 2416 | else |
| 2417 | { |
| 2418 | BFD_ASSERT ((bfd_get_flavour (input_sec->owner) |
| 2419 | == bfd_target_elf_flavour) |
| 2420 | && elf_elfheader (input_sec->owner)->e_type == ET_DYN); |
| 2421 | sym.st_shndx = SHN_UNDEF; |
| 2422 | input_sec = bfd_und_section_ptr; |
| 2423 | } |
| 2424 | } |
| 2425 | break; |
| 2426 | |
| 2427 | case bfd_link_hash_common: |
| 2428 | input_sec = bfd_com_section_ptr; |
| 2429 | sym.st_shndx = SHN_COMMON; |
| 2430 | sym.st_value = 1 << h->root.u.c.p->alignment_power; |
| 2431 | break; |
| 2432 | |
| 2433 | case bfd_link_hash_indirect: |
| 2434 | case bfd_link_hash_warning: |
| 2435 | /* I have no idea how these should be handled. */ |
| 2436 | return true; |
| 2437 | } |
| 2438 | |
| 2439 | /* If this symbol should be put in the .dynsym section, then put it |
| 2440 | there now. We have already know the symbol index. We also fill |
| 2441 | in the entry in the .hash section. */ |
| 2442 | if (h->dynindx != -1 |
| 2443 | && elf_hash_table (finfo->info)->dynamic_sections_created) |
| 2444 | { |
| 2445 | struct elf_backend_data *bed; |
| 2446 | size_t bucketcount; |
| 2447 | size_t bucket; |
| 2448 | bfd_byte *bucketpos; |
| 2449 | bfd_vma chain; |
| 2450 | |
| 2451 | sym.st_name = h->dynstr_index; |
| 2452 | |
| 2453 | /* Give the processor backend a chance to tweak the symbol |
| 2454 | value, and also to finish up anything that needs to be done |
| 2455 | for this symbol. */ |
| 2456 | bed = get_elf_backend_data (finfo->output_bfd); |
| 2457 | if (! ((*bed->elf_backend_finish_dynamic_symbol) |
| 2458 | (finfo->output_bfd, finfo->info, h, &sym))) |
| 2459 | { |
| 2460 | eif->failed = true; |
| 2461 | return false; |
| 2462 | } |
| 2463 | |
| 2464 | elf_swap_symbol_out (finfo->output_bfd, &sym, |
| 2465 | (PTR) (((Elf_External_Sym *) |
| 2466 | finfo->dynsym_sec->contents) |
| 2467 | + h->dynindx)); |
| 2468 | |
| 2469 | bucketcount = elf_hash_table (finfo->info)->bucketcount; |
| 2470 | bucket = (bfd_elf_hash ((const unsigned char *) h->root.root.string) |
| 2471 | % bucketcount); |
| 2472 | bucketpos = ((bfd_byte *) finfo->hash_sec->contents |
| 2473 | + (bucket + 2) * (ARCH_SIZE / 8)); |
| 2474 | chain = get_word (finfo->output_bfd, bucketpos); |
| 2475 | put_word (finfo->output_bfd, h->dynindx, bucketpos); |
| 2476 | put_word (finfo->output_bfd, chain, |
| 2477 | ((bfd_byte *) finfo->hash_sec->contents |
| 2478 | + (bucketcount + 2 + h->dynindx) * (ARCH_SIZE / 8))); |
| 2479 | } |
| 2480 | |
| 2481 | /* If we're stripping it, then it was just a dynamic symbol, and |
| 2482 | there's nothing else to do. */ |
| 2483 | if (strip) |
| 2484 | return true; |
| 2485 | |
| 2486 | h->indx = finfo->output_bfd->symcount; |
| 2487 | |
| 2488 | if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec)) |
| 2489 | { |
| 2490 | eif->failed = true; |
| 2491 | return false; |
| 2492 | } |
| 2493 | |
| 2494 | return true; |
| 2495 | } |
| 2496 | |
| 2497 | /* Link an input file into the linker output file. This function |
| 2498 | handles all the sections and relocations of the input file at once. |
| 2499 | This is so that we only have to read the local symbols once, and |
| 2500 | don't have to keep them in memory. */ |
| 2501 | |
| 2502 | static boolean |
| 2503 | elf_link_input_bfd (finfo, input_bfd) |
| 2504 | struct elf_final_link_info *finfo; |
| 2505 | bfd *input_bfd; |
| 2506 | { |
| 2507 | boolean (*relocate_section) PARAMS ((bfd *, struct bfd_link_info *, |
| 2508 | bfd *, asection *, bfd_byte *, |
| 2509 | Elf_Internal_Rela *, |
| 2510 | Elf_Internal_Sym *, asection **)); |
| 2511 | bfd *output_bfd; |
| 2512 | Elf_Internal_Shdr *symtab_hdr; |
| 2513 | size_t locsymcount; |
| 2514 | size_t extsymoff; |
| 2515 | Elf_External_Sym *esym; |
| 2516 | Elf_External_Sym *esymend; |
| 2517 | Elf_Internal_Sym *isym; |
| 2518 | long *pindex; |
| 2519 | asection **ppsection; |
| 2520 | asection *o; |
| 2521 | |
| 2522 | output_bfd = finfo->output_bfd; |
| 2523 | relocate_section = |
| 2524 | get_elf_backend_data (output_bfd)->elf_backend_relocate_section; |
| 2525 | |
| 2526 | /* If this is a dynamic object, we don't want to do anything here: |
| 2527 | we don't want the local symbols, and we don't want the section |
| 2528 | contents. */ |
| 2529 | if (elf_elfheader (input_bfd)->e_type == ET_DYN) |
| 2530 | return true; |
| 2531 | |
| 2532 | symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr; |
| 2533 | if (elf_bad_symtab (input_bfd)) |
| 2534 | { |
| 2535 | locsymcount = symtab_hdr->sh_size / sizeof (Elf_External_Sym); |
| 2536 | extsymoff = 0; |
| 2537 | } |
| 2538 | else |
| 2539 | { |
| 2540 | locsymcount = symtab_hdr->sh_info; |
| 2541 | extsymoff = symtab_hdr->sh_info; |
| 2542 | } |
| 2543 | |
| 2544 | /* Read the local symbols. */ |
| 2545 | if (locsymcount > 0 |
| 2546 | && (bfd_seek (input_bfd, symtab_hdr->sh_offset, SEEK_SET) != 0 |
| 2547 | || (bfd_read (finfo->external_syms, sizeof (Elf_External_Sym), |
| 2548 | locsymcount, input_bfd) |
| 2549 | != locsymcount * sizeof (Elf_External_Sym)))) |
| 2550 | return false; |
| 2551 | |
| 2552 | /* Swap in the local symbols and write out the ones which we know |
| 2553 | are going into the output file. */ |
| 2554 | esym = finfo->external_syms; |
| 2555 | esymend = esym + locsymcount; |
| 2556 | isym = finfo->internal_syms; |
| 2557 | pindex = finfo->indices; |
| 2558 | ppsection = finfo->sections; |
| 2559 | for (; esym < esymend; esym++, isym++, pindex++, ppsection++) |
| 2560 | { |
| 2561 | asection *isec; |
| 2562 | const char *name; |
| 2563 | Elf_Internal_Sym osym; |
| 2564 | |
| 2565 | elf_swap_symbol_in (input_bfd, esym, isym); |
| 2566 | *pindex = -1; |
| 2567 | |
| 2568 | if (elf_bad_symtab (input_bfd)) |
| 2569 | { |
| 2570 | if (ELF_ST_BIND (isym->st_info) != STB_LOCAL) |
| 2571 | { |
| 2572 | *ppsection = NULL; |
| 2573 | continue; |
| 2574 | } |
| 2575 | } |
| 2576 | |
| 2577 | if (isym->st_shndx == SHN_UNDEF) |
| 2578 | isec = bfd_und_section_ptr; |
| 2579 | else if (isym->st_shndx > 0 && isym->st_shndx < SHN_LORESERVE) |
| 2580 | isec = section_from_elf_index (input_bfd, isym->st_shndx); |
| 2581 | else if (isym->st_shndx == SHN_ABS) |
| 2582 | isec = bfd_abs_section_ptr; |
| 2583 | else if (isym->st_shndx == SHN_COMMON) |
| 2584 | isec = bfd_com_section_ptr; |
| 2585 | else |
| 2586 | { |
| 2587 | /* Who knows? */ |
| 2588 | isec = NULL; |
| 2589 | } |
| 2590 | |
| 2591 | *ppsection = isec; |
| 2592 | |
| 2593 | /* Don't output the first, undefined, symbol. */ |
| 2594 | if (esym == finfo->external_syms) |
| 2595 | continue; |
| 2596 | |
| 2597 | /* If we are stripping all symbols, we don't want to output this |
| 2598 | one. */ |
| 2599 | if (finfo->info->strip == strip_all) |
| 2600 | continue; |
| 2601 | |
| 2602 | /* We never output section symbols. Instead, we use the section |
| 2603 | symbol of the corresponding section in the output file. */ |
| 2604 | if (ELF_ST_TYPE (isym->st_info) == STT_SECTION) |
| 2605 | continue; |
| 2606 | |
| 2607 | /* If we are discarding all local symbols, we don't want to |
| 2608 | output this one. If we are generating a relocateable output |
| 2609 | file, then some of the local symbols may be required by |
| 2610 | relocs; we output them below as we discover that they are |
| 2611 | needed. */ |
| 2612 | if (finfo->info->discard == discard_all) |
| 2613 | continue; |
| 2614 | |
| 2615 | /* Get the name of the symbol. */ |
| 2616 | name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link, |
| 2617 | isym->st_name); |
| 2618 | if (name == NULL) |
| 2619 | return false; |
| 2620 | |
| 2621 | /* See if we are discarding symbols with this name. */ |
| 2622 | if ((finfo->info->strip == strip_some |
| 2623 | && (bfd_hash_lookup (finfo->info->keep_hash, name, false, false) |
| 2624 | == NULL)) |
| 2625 | || (finfo->info->discard == discard_l |
| 2626 | && strncmp (name, finfo->info->lprefix, |
| 2627 | finfo->info->lprefix_len) == 0)) |
| 2628 | continue; |
| 2629 | |
| 2630 | /* If we get here, we are going to output this symbol. */ |
| 2631 | |
| 2632 | osym = *isym; |
| 2633 | |
| 2634 | /* Adjust the section index for the output file. */ |
| 2635 | osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd, |
| 2636 | isec->output_section); |
| 2637 | if (osym.st_shndx == (unsigned short) -1) |
| 2638 | return false; |
| 2639 | |
| 2640 | *pindex = output_bfd->symcount; |
| 2641 | |
| 2642 | /* ELF symbols in relocateable files are section relative, but |
| 2643 | in executable files they are virtual addresses. Note that |
| 2644 | this code assumes that all ELF sections have an associated |
| 2645 | BFD section with a reasonable value for output_offset; below |
| 2646 | we assume that they also have a reasonable value for |
| 2647 | output_section. Any special sections must be set up to meet |
| 2648 | these requirements. */ |
| 2649 | osym.st_value += isec->output_offset; |
| 2650 | if (! finfo->info->relocateable) |
| 2651 | osym.st_value += isec->output_section->vma; |
| 2652 | |
| 2653 | if (! elf_link_output_sym (finfo, name, &osym, isec)) |
| 2654 | return false; |
| 2655 | } |
| 2656 | |
| 2657 | /* Relocate the contents of each section. */ |
| 2658 | for (o = input_bfd->sections; o != NULL; o = o->next) |
| 2659 | { |
| 2660 | if ((o->flags & SEC_HAS_CONTENTS) == 0) |
| 2661 | continue; |
| 2662 | |
| 2663 | if ((o->flags & SEC_IN_MEMORY) != 0 |
| 2664 | && input_bfd == elf_hash_table (finfo->info)->dynobj) |
| 2665 | { |
| 2666 | /* Section was created by elf_link_create_dynamic_sections. |
| 2667 | FIXME: This test is fragile. */ |
| 2668 | continue; |
| 2669 | } |
| 2670 | |
| 2671 | /* Read the contents of the section. */ |
| 2672 | if (! bfd_get_section_contents (input_bfd, o, finfo->contents, |
| 2673 | (file_ptr) 0, o->_raw_size)) |
| 2674 | return false; |
| 2675 | |
| 2676 | if ((o->flags & SEC_RELOC) != 0) |
| 2677 | { |
| 2678 | Elf_Internal_Rela *internal_relocs; |
| 2679 | |
| 2680 | /* Get the swapped relocs. */ |
| 2681 | internal_relocs = elf_link_read_relocs (input_bfd, o, |
| 2682 | finfo->external_relocs, |
| 2683 | finfo->internal_relocs, |
| 2684 | false); |
| 2685 | if (internal_relocs == NULL |
| 2686 | && o->reloc_count > 0) |
| 2687 | return false; |
| 2688 | |
| 2689 | /* Relocate the section by invoking a back end routine. |
| 2690 | |
| 2691 | The back end routine is responsible for adjusting the |
| 2692 | section contents as necessary, and (if using Rela relocs |
| 2693 | and generating a relocateable output file) adjusting the |
| 2694 | reloc addend as necessary. |
| 2695 | |
| 2696 | The back end routine does not have to worry about setting |
| 2697 | the reloc address or the reloc symbol index. |
| 2698 | |
| 2699 | The back end routine is given a pointer to the swapped in |
| 2700 | internal symbols, and can access the hash table entries |
| 2701 | for the external symbols via elf_sym_hashes (input_bfd). |
| 2702 | |
| 2703 | When generating relocateable output, the back end routine |
| 2704 | must handle STB_LOCAL/STT_SECTION symbols specially. The |
| 2705 | output symbol is going to be a section symbol |
| 2706 | corresponding to the output section, which will require |
| 2707 | the addend to be adjusted. */ |
| 2708 | |
| 2709 | if (! (*relocate_section) (output_bfd, finfo->info, |
| 2710 | input_bfd, o, |
| 2711 | finfo->contents, |
| 2712 | internal_relocs, |
| 2713 | finfo->internal_syms, |
| 2714 | finfo->sections)) |
| 2715 | return false; |
| 2716 | |
| 2717 | if (finfo->info->relocateable) |
| 2718 | { |
| 2719 | Elf_Internal_Rela *irela; |
| 2720 | Elf_Internal_Rela *irelaend; |
| 2721 | struct elf_link_hash_entry **rel_hash; |
| 2722 | Elf_Internal_Shdr *input_rel_hdr; |
| 2723 | Elf_Internal_Shdr *output_rel_hdr; |
| 2724 | |
| 2725 | /* Adjust the reloc addresses and symbol indices. */ |
| 2726 | |
| 2727 | irela = internal_relocs; |
| 2728 | irelaend = irela + o->reloc_count; |
| 2729 | rel_hash = (elf_section_data (o->output_section)->rel_hashes |
| 2730 | + o->output_section->reloc_count); |
| 2731 | for (; irela < irelaend; irela++, rel_hash++) |
| 2732 | { |
| 2733 | long r_symndx; |
| 2734 | Elf_Internal_Sym *isym; |
| 2735 | asection *sec; |
| 2736 | |
| 2737 | irela->r_offset += o->output_offset; |
| 2738 | |
| 2739 | r_symndx = ELF_R_SYM (irela->r_info); |
| 2740 | |
| 2741 | if (r_symndx == 0) |
| 2742 | continue; |
| 2743 | |
| 2744 | if (r_symndx >= locsymcount |
| 2745 | || (elf_bad_symtab (input_bfd) |
| 2746 | && finfo->sections[r_symndx] == NULL)) |
| 2747 | { |
| 2748 | long indx; |
| 2749 | |
| 2750 | /* This is a reloc against a global symbol. We |
| 2751 | have not yet output all the local symbols, so |
| 2752 | we do not know the symbol index of any global |
| 2753 | symbol. We set the rel_hash entry for this |
| 2754 | reloc to point to the global hash table entry |
| 2755 | for this symbol. The symbol index is then |
| 2756 | set at the end of elf_bfd_final_link. */ |
| 2757 | indx = r_symndx - extsymoff; |
| 2758 | *rel_hash = elf_sym_hashes (input_bfd)[indx]; |
| 2759 | |
| 2760 | /* Setting the index to -2 tells |
| 2761 | elf_link_output_extsym that this symbol is |
| 2762 | used by a reloc. */ |
| 2763 | BFD_ASSERT ((*rel_hash)->indx < 0); |
| 2764 | (*rel_hash)->indx = -2; |
| 2765 | |
| 2766 | continue; |
| 2767 | } |
| 2768 | |
| 2769 | /* This is a reloc against a local symbol. */ |
| 2770 | |
| 2771 | *rel_hash = NULL; |
| 2772 | isym = finfo->internal_syms + r_symndx; |
| 2773 | sec = finfo->sections[r_symndx]; |
| 2774 | if (ELF_ST_TYPE (isym->st_info) == STT_SECTION) |
| 2775 | { |
| 2776 | /* I suppose the backend ought to fill in the |
| 2777 | section of any STT_SECTION symbol against a |
| 2778 | processor specific section. */ |
| 2779 | if (sec != NULL && bfd_is_abs_section (sec)) |
| 2780 | r_symndx = 0; |
| 2781 | else if (sec == NULL || sec->owner == NULL) |
| 2782 | { |
| 2783 | bfd_set_error (bfd_error_bad_value); |
| 2784 | return false; |
| 2785 | } |
| 2786 | else |
| 2787 | { |
| 2788 | r_symndx = sec->output_section->target_index; |
| 2789 | BFD_ASSERT (r_symndx != 0); |
| 2790 | } |
| 2791 | } |
| 2792 | else |
| 2793 | { |
| 2794 | if (finfo->indices[r_symndx] == -1) |
| 2795 | { |
| 2796 | unsigned long link; |
| 2797 | const char *name; |
| 2798 | asection *osec; |
| 2799 | |
| 2800 | if (finfo->info->strip == strip_all) |
| 2801 | { |
| 2802 | /* You can't do ld -r -s. */ |
| 2803 | bfd_set_error (bfd_error_invalid_operation); |
| 2804 | return false; |
| 2805 | } |
| 2806 | |
| 2807 | /* This symbol was skipped earlier, but |
| 2808 | since it is needed by a reloc, we |
| 2809 | must output it now. */ |
| 2810 | link = symtab_hdr->sh_link; |
| 2811 | name = bfd_elf_string_from_elf_section (input_bfd, |
| 2812 | link, |
| 2813 | isym->st_name); |
| 2814 | if (name == NULL) |
| 2815 | return false; |
| 2816 | |
| 2817 | osec = sec->output_section; |
| 2818 | isym->st_shndx = |
| 2819 | _bfd_elf_section_from_bfd_section (output_bfd, |
| 2820 | osec); |
| 2821 | if (isym->st_shndx == (unsigned short) -1) |
| 2822 | return false; |
| 2823 | |
| 2824 | isym->st_value += sec->output_offset; |
| 2825 | if (! finfo->info->relocateable) |
| 2826 | isym->st_value += osec->vma; |
| 2827 | |
| 2828 | finfo->indices[r_symndx] = output_bfd->symcount; |
| 2829 | |
| 2830 | if (! elf_link_output_sym (finfo, name, isym, sec)) |
| 2831 | return false; |
| 2832 | } |
| 2833 | |
| 2834 | r_symndx = finfo->indices[r_symndx]; |
| 2835 | } |
| 2836 | |
| 2837 | irela->r_info = ELF_R_INFO (r_symndx, |
| 2838 | ELF_R_TYPE (irela->r_info)); |
| 2839 | } |
| 2840 | |
| 2841 | /* Swap out the relocs. */ |
| 2842 | input_rel_hdr = &elf_section_data (o)->rel_hdr; |
| 2843 | output_rel_hdr = &elf_section_data (o->output_section)->rel_hdr; |
| 2844 | BFD_ASSERT (output_rel_hdr->sh_entsize |
| 2845 | == input_rel_hdr->sh_entsize); |
| 2846 | irela = internal_relocs; |
| 2847 | irelaend = irela + o->reloc_count; |
| 2848 | if (input_rel_hdr->sh_entsize == sizeof (Elf_External_Rel)) |
| 2849 | { |
| 2850 | Elf_External_Rel *erel; |
| 2851 | |
| 2852 | erel = ((Elf_External_Rel *) output_rel_hdr->contents |
| 2853 | + o->output_section->reloc_count); |
| 2854 | for (; irela < irelaend; irela++, erel++) |
| 2855 | { |
| 2856 | Elf_Internal_Rel irel; |
| 2857 | |
| 2858 | irel.r_offset = irela->r_offset; |
| 2859 | irel.r_info = irela->r_info; |
| 2860 | BFD_ASSERT (irela->r_addend == 0); |
| 2861 | elf_swap_reloc_out (output_bfd, &irel, erel); |
| 2862 | } |
| 2863 | } |
| 2864 | else |
| 2865 | { |
| 2866 | Elf_External_Rela *erela; |
| 2867 | |
| 2868 | BFD_ASSERT (input_rel_hdr->sh_entsize |
| 2869 | == sizeof (Elf_External_Rela)); |
| 2870 | erela = ((Elf_External_Rela *) output_rel_hdr->contents |
| 2871 | + o->output_section->reloc_count); |
| 2872 | for (; irela < irelaend; irela++, erela++) |
| 2873 | elf_swap_reloca_out (output_bfd, irela, erela); |
| 2874 | } |
| 2875 | |
| 2876 | o->output_section->reloc_count += o->reloc_count; |
| 2877 | } |
| 2878 | } |
| 2879 | |
| 2880 | /* Write out the modified section contents. */ |
| 2881 | if (! bfd_set_section_contents (output_bfd, o->output_section, |
| 2882 | finfo->contents, o->output_offset, |
| 2883 | (o->_cooked_size != 0 |
| 2884 | ? o->_cooked_size |
| 2885 | : o->_raw_size))) |
| 2886 | return false; |
| 2887 | } |
| 2888 | |
| 2889 | return true; |
| 2890 | } |
| 2891 | |
| 2892 | /* Generate a reloc when linking an ELF file. This is a reloc |
| 2893 | requested by the linker, and does come from any input file. This |
| 2894 | is used to build constructor and destructor tables when linking |
| 2895 | with -Ur. */ |
| 2896 | |
| 2897 | static boolean |
| 2898 | elf_reloc_link_order (output_bfd, info, output_section, link_order) |
| 2899 | bfd *output_bfd; |
| 2900 | struct bfd_link_info *info; |
| 2901 | asection *output_section; |
| 2902 | struct bfd_link_order *link_order; |
| 2903 | { |
| 2904 | reloc_howto_type *howto; |
| 2905 | long indx; |
| 2906 | bfd_vma offset; |
| 2907 | struct elf_link_hash_entry **rel_hash_ptr; |
| 2908 | Elf_Internal_Shdr *rel_hdr; |
| 2909 | |
| 2910 | howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc); |
| 2911 | if (howto == NULL) |
| 2912 | { |
| 2913 | bfd_set_error (bfd_error_bad_value); |
| 2914 | return false; |
| 2915 | } |
| 2916 | |
| 2917 | /* If this is an inplace reloc, we must write the addend into the |
| 2918 | object file. */ |
| 2919 | if (howto->partial_inplace |
| 2920 | && link_order->u.reloc.p->addend != 0) |
| 2921 | { |
| 2922 | bfd_size_type size; |
| 2923 | bfd_reloc_status_type rstat; |
| 2924 | bfd_byte *buf; |
| 2925 | boolean ok; |
| 2926 | |
| 2927 | size = bfd_get_reloc_size (howto); |
| 2928 | buf = (bfd_byte *) bfd_zmalloc (size); |
| 2929 | if (buf == (bfd_byte *) NULL) |
| 2930 | { |
| 2931 | bfd_set_error (bfd_error_no_memory); |
| 2932 | return false; |
| 2933 | } |
| 2934 | rstat = _bfd_relocate_contents (howto, output_bfd, |
| 2935 | link_order->u.reloc.p->addend, buf); |
| 2936 | switch (rstat) |
| 2937 | { |
| 2938 | case bfd_reloc_ok: |
| 2939 | break; |
| 2940 | default: |
| 2941 | case bfd_reloc_outofrange: |
| 2942 | abort (); |
| 2943 | case bfd_reloc_overflow: |
| 2944 | if (! ((*info->callbacks->reloc_overflow) |
| 2945 | (info, |
| 2946 | (link_order->type == bfd_section_reloc_link_order |
| 2947 | ? bfd_section_name (output_bfd, |
| 2948 | link_order->u.reloc.p->u.section) |
| 2949 | : link_order->u.reloc.p->u.name), |
| 2950 | howto->name, link_order->u.reloc.p->addend, |
| 2951 | (bfd *) NULL, (asection *) NULL, (bfd_vma) 0))) |
| 2952 | { |
| 2953 | free (buf); |
| 2954 | return false; |
| 2955 | } |
| 2956 | break; |
| 2957 | } |
| 2958 | ok = bfd_set_section_contents (output_bfd, output_section, (PTR) buf, |
| 2959 | (file_ptr) link_order->offset, size); |
| 2960 | free (buf); |
| 2961 | if (! ok) |
| 2962 | return false; |
| 2963 | } |
| 2964 | |
| 2965 | /* Figure out the symbol index. */ |
| 2966 | rel_hash_ptr = (elf_section_data (output_section)->rel_hashes |
| 2967 | + output_section->reloc_count); |
| 2968 | if (link_order->type == bfd_section_reloc_link_order) |
| 2969 | { |
| 2970 | indx = link_order->u.reloc.p->u.section->target_index; |
| 2971 | BFD_ASSERT (indx != 0); |
| 2972 | *rel_hash_ptr = NULL; |
| 2973 | } |
| 2974 | else |
| 2975 | { |
| 2976 | struct elf_link_hash_entry *h; |
| 2977 | |
| 2978 | h = elf_link_hash_lookup (elf_hash_table (info), |
| 2979 | link_order->u.reloc.p->u.name, |
| 2980 | false, false, true); |
| 2981 | if (h != NULL) |
| 2982 | { |
| 2983 | /* Setting the index to -2 tells elf_link_output_extsym that |
| 2984 | this symbol is used by a reloc. */ |
| 2985 | h->indx = -2; |
| 2986 | *rel_hash_ptr = h; |
| 2987 | indx = 0; |
| 2988 | } |
| 2989 | else |
| 2990 | { |
| 2991 | if (! ((*info->callbacks->unattached_reloc) |
| 2992 | (info, link_order->u.reloc.p->u.name, (bfd *) NULL, |
| 2993 | (asection *) NULL, (bfd_vma) 0))) |
| 2994 | return false; |
| 2995 | indx = 0; |
| 2996 | } |
| 2997 | } |
| 2998 | |
| 2999 | /* The address of a reloc is relative to the section in a |
| 3000 | relocateable file, and is a virtual address in an executable |
| 3001 | file. */ |
| 3002 | offset = link_order->offset; |
| 3003 | if (! info->relocateable) |
| 3004 | offset += output_section->vma; |
| 3005 | |
| 3006 | rel_hdr = &elf_section_data (output_section)->rel_hdr; |
| 3007 | |
| 3008 | if (rel_hdr->sh_type == SHT_REL) |
| 3009 | { |
| 3010 | Elf_Internal_Rel irel; |
| 3011 | Elf_External_Rel *erel; |
| 3012 | |
| 3013 | irel.r_offset = offset; |
| 3014 | irel.r_info = ELF_R_INFO (indx, howto->type); |
| 3015 | erel = ((Elf_External_Rel *) rel_hdr->contents |
| 3016 | + output_section->reloc_count); |
| 3017 | elf_swap_reloc_out (output_bfd, &irel, erel); |
| 3018 | } |
| 3019 | else |
| 3020 | { |
| 3021 | Elf_Internal_Rela irela; |
| 3022 | Elf_External_Rela *erela; |
| 3023 | |
| 3024 | irela.r_offset = offset; |
| 3025 | irela.r_info = ELF_R_INFO (indx, howto->type); |
| 3026 | irela.r_addend = link_order->u.reloc.p->addend; |
| 3027 | erela = ((Elf_External_Rela *) rel_hdr->contents |
| 3028 | + output_section->reloc_count); |
| 3029 | elf_swap_reloca_out (output_bfd, &irela, erela); |
| 3030 | } |
| 3031 | |
| 3032 | ++output_section->reloc_count; |
| 3033 | |
| 3034 | return true; |
| 3035 | } |
| 3036 | |