elf32.em revision 68778
1# $FreeBSD: head/contrib/binutils/ld/emultempl/elf32.em 68778 2000-11-15 21:26:21Z obrien $ 2# This shell script emits a C file. -*- C -*- 3# It does some substitutions. 4# This file is now misnamed, because it supports both 32 bit and 64 bit 5# ELF emulations. 6test -z "${ELFSIZE}" && ELFSIZE=32 7cat >e${EMULATION_NAME}.c <<EOF 8/* This file is is generated by a shell script. DO NOT EDIT! */ 9 10/* ${ELFSIZE} bit ELF emulation code for ${EMULATION_NAME} 11 Copyright (C) 1991, 93, 94, 95, 96, 97, 98, 99, 2000 12 Free Software Foundation, Inc. 13 Written by Steve Chamberlain <sac@cygnus.com> 14 ELF support by Ian Lance Taylor <ian@cygnus.com> 15 16This file is part of GLD, the Gnu Linker. 17 18This program is free software; you can redistribute it and/or modify 19it under the terms of the GNU General Public License as published by 20the Free Software Foundation; either version 2 of the License, or 21(at your option) any later version. 22 23This program is distributed in the hope that it will be useful, 24but WITHOUT ANY WARRANTY; without even the implied warranty of 25MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 26GNU General Public License for more details. 27 28You should have received a copy of the GNU General Public License 29along with this program; if not, write to the Free Software 30Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 31 32#define TARGET_IS_${EMULATION_NAME} 33 34#include "bfd.h" 35#include "sysdep.h" 36 37#include <ctype.h> 38 39#include "bfdlink.h" 40 41#include "ld.h" 42#include "ldmain.h" 43#include "ldemul.h" 44#include "ldfile.h" 45#include "ldmisc.h" 46#include "ldexp.h" 47#include "ldlang.h" 48#include "ldgram.h" 49 50static void gld${EMULATION_NAME}_before_parse PARAMS ((void)); 51static boolean gld${EMULATION_NAME}_open_dynamic_archive 52 PARAMS ((const char *, search_dirs_type *, lang_input_statement_type *)); 53static void gld${EMULATION_NAME}_after_open PARAMS ((void)); 54static void gld${EMULATION_NAME}_check_needed 55 PARAMS ((lang_input_statement_type *)); 56static void gld${EMULATION_NAME}_stat_needed 57 PARAMS ((lang_input_statement_type *)); 58static boolean gld${EMULATION_NAME}_search_needed 59 PARAMS ((const char *, const char *, int)); 60static boolean gld${EMULATION_NAME}_try_needed PARAMS ((const char *, int)); 61static void gld${EMULATION_NAME}_vercheck 62 PARAMS ((lang_input_statement_type *)); 63static void gld${EMULATION_NAME}_before_allocation PARAMS ((void)); 64static void gld${EMULATION_NAME}_find_statement_assignment 65 PARAMS ((lang_statement_union_type *)); 66static void gld${EMULATION_NAME}_find_exp_assignment PARAMS ((etree_type *)); 67static lang_output_section_statement_type *output_rel_find PARAMS ((void)); 68static boolean gld${EMULATION_NAME}_place_orphan 69 PARAMS ((lang_input_statement_type *, asection *)); 70static char *gld${EMULATION_NAME}_get_script PARAMS ((int *isfile)); 71 72static void 73gld${EMULATION_NAME}_before_parse() 74{ 75 ldfile_output_architecture = bfd_arch_`echo ${ARCH} | sed -e 's/:.*//'`; 76 config.dynamic_link = ${DYNAMIC_LINK-true}; 77 config.has_shared = `if test -n "$GENERATE_SHLIB_SCRIPT" ; then echo true ; else echo false ; fi`; 78} 79 80/* Try to open a dynamic archive. This is where we know that ELF 81 dynamic libraries have an extension of .so (or .sl on oddball systems 82 like hpux). */ 83 84static boolean 85gld${EMULATION_NAME}_open_dynamic_archive (arch, search, entry) 86 const char *arch; 87 search_dirs_type *search; 88 lang_input_statement_type *entry; 89{ 90 const char *filename; 91 char *string; 92 93 if (! entry->is_archive) 94 return false; 95 96 filename = entry->filename; 97 98 /* This allocates a few bytes too many when EXTRA_SHLIB_EXTENSION 99 is defined, but it does not seem worth the headache to optimize 100 away those two bytes of space. */ 101 string = (char *) xmalloc (strlen (search->name) 102 + strlen (filename) 103 + strlen (arch) 104#ifdef EXTRA_SHLIB_EXTENSION 105 + strlen (EXTRA_SHLIB_EXTENSION) 106#endif 107 + sizeof "/lib.so"); 108 109 sprintf (string, "%s/lib%s%s.so", search->name, filename, arch); 110 111#ifdef EXTRA_SHLIB_EXTENSION 112 /* Try the .so extension first. If that fails build a new filename 113 using EXTRA_SHLIB_EXTENSION. */ 114 if (! ldfile_try_open_bfd (string, entry)) 115 sprintf (string, "%s/lib%s%s%s", search->name, 116 filename, arch, EXTRA_SHLIB_EXTENSION); 117#endif 118 119 if (! ldfile_try_open_bfd (string, entry)) 120 { 121 free (string); 122 return false; 123 } 124 125 entry->filename = string; 126 127 /* We have found a dynamic object to include in the link. The ELF 128 backend linker will create a DT_NEEDED entry in the .dynamic 129 section naming this file. If this file includes a DT_SONAME 130 entry, it will be used. Otherwise, the ELF linker will just use 131 the name of the file. For an archive found by searching, like 132 this one, the DT_NEEDED entry should consist of just the name of 133 the file, without the path information used to find it. Note 134 that we only need to do this if we have a dynamic object; an 135 archive will never be referenced by a DT_NEEDED entry. 136 137 FIXME: This approach--using bfd_elf_set_dt_needed_name--is not 138 very pretty. I haven't been able to think of anything that is 139 pretty, though. */ 140 if (bfd_check_format (entry->the_bfd, bfd_object) 141 && (entry->the_bfd->flags & DYNAMIC) != 0) 142 { 143 char *needed_name; 144 145 ASSERT (entry->is_archive && entry->search_dirs_flag); 146 147 /* Rather than duplicating the logic above. Just use the 148 filename we recorded earlier. 149 150 First strip off everything before the last '/'. */ 151 filename = strrchr (entry->filename, '/'); 152 filename++; 153 154 needed_name = (char *) xmalloc (strlen (filename) + 1); 155 strcpy (needed_name, filename); 156 bfd_elf_set_dt_needed_name (entry->the_bfd, needed_name); 157 } 158 159 return true; 160} 161 162EOF 163if [ "x${host}" = "x${target}" ] ; then 164 case " ${EMULATION_LIBPATH} " in 165 *" ${EMULATION_NAME} "*) 166 case ${target} in 167 *-*-freebsd*) 168 cat >>e${EMULATION_NAME}.c <<EOF 169/* 170 * Read the system search path the FreeBSD way rather than like Linux. 171 */ 172#include <elf.h> 173 174static boolean gld${EMULATION_NAME}_check_ld_elf_hints 175 PARAMS ((const char *, int)); 176 177static boolean 178gld${EMULATION_NAME}_check_ld_elf_hints (name, force) 179 const char *name; 180 int force; 181{ 182 static boolean initialized; 183 static char *ld_elf_hints; 184 185 if (! initialized) 186 { 187 FILE *f; 188 189 f = fopen (_PATH_ELF_HINTS, FOPEN_RB); 190 if (f != NULL) 191 { 192 struct elfhints_hdr hdr; 193 194 if (fread(&hdr, 1, sizeof(hdr), f) == sizeof(hdr) && 195 hdr.magic == ELFHINTS_MAGIC && 196 hdr.version == 1) 197 { 198 if (fseek(f, hdr.strtab + hdr.dirlist, SEEK_SET) != -1) 199 { 200 char *b; 201 202 b = (char *) xmalloc (hdr.dirlistlen + 1); 203 if (fread(b, 1, hdr.dirlistlen + 1, f) != 204 hdr.dirlistlen + 1) 205 { 206 free(b); 207 } 208 else 209 { 210 ld_elf_hints = b; 211 } 212 } 213 } 214 fclose (f); 215 } 216 217 initialized = true; 218 } 219 220 if (ld_elf_hints == NULL) 221 return false; 222 223 return gld${EMULATION_NAME}_search_needed (ld_elf_hints, name, force); 224} 225EOF 226 ;; 227 228 *linux*|*Linux*|*LINUX*) 229 cat >>e${EMULATION_NAME}.c <<EOF 230 231/* For a native linker, check the file /etc/ld.so.conf for directories 232 in which we may find shared libraries. /etc/ld.so.conf is really 233 only meaningful on Linux. */ 234 235static boolean gld${EMULATION_NAME}_check_ld_so_conf 236 PARAMS ((const char *, int)); 237 238static boolean 239gld${EMULATION_NAME}_check_ld_so_conf (name, force) 240 const char *name; 241 int force; 242{ 243 static boolean initialized; 244 static char *ld_so_conf; 245 246 if (! initialized) 247 { 248 FILE *f; 249 250 f = fopen ("/etc/ld.so.conf", FOPEN_RT); 251 if (f != NULL) 252 { 253 char *b; 254 size_t len, alloc; 255 int c; 256 257 len = 0; 258 alloc = 100; 259 b = (char *) xmalloc (alloc); 260 261 while ((c = getc (f)) != EOF) 262 { 263 if (len + 1 >= alloc) 264 { 265 alloc *= 2; 266 b = (char *) xrealloc (b, alloc); 267 } 268 if (c != ':' 269 && c != ' ' 270 && c != '\t' 271 && c != '\n' 272 && c != ',') 273 { 274 b[len] = c; 275 ++len; 276 } 277 else 278 { 279 if (len > 0 && b[len - 1] != ':') 280 { 281 b[len] = ':'; 282 ++len; 283 } 284 } 285 } 286 287 if (len > 0 && b[len - 1] == ':') 288 --len; 289 290 if (len > 0) 291 b[len] = '\0'; 292 else 293 { 294 free (b); 295 b = NULL; 296 } 297 298 fclose (f); 299 300 ld_so_conf = b; 301 } 302 303 initialized = true; 304 } 305 306 if (ld_so_conf == NULL) 307 return false; 308 309 return gld${EMULATION_NAME}_search_needed (ld_so_conf, name, force); 310} 311 312EOF 313 ;; 314 esac 315 esac 316fi 317cat >>e${EMULATION_NAME}.c <<EOF 318 319/* These variables are required to pass information back and forth 320 between after_open and check_needed and stat_needed and vercheck. */ 321 322static struct bfd_link_needed_list *global_needed; 323static struct stat global_stat; 324static boolean global_found; 325static struct bfd_link_needed_list *global_vercheck_needed; 326static boolean global_vercheck_failed; 327 328/* This is called after all the input files have been opened. */ 329 330static void 331gld${EMULATION_NAME}_after_open () 332{ 333 struct bfd_link_needed_list *needed, *l; 334 335 /* We only need to worry about this when doing a final link. */ 336 if (link_info.relocateable || link_info.shared) 337 return; 338 339 /* Get the list of files which appear in DT_NEEDED entries in 340 dynamic objects included in the link (often there will be none). 341 For each such file, we want to track down the corresponding 342 library, and include the symbol table in the link. This is what 343 the runtime dynamic linker will do. Tracking the files down here 344 permits one dynamic object to include another without requiring 345 special action by the person doing the link. Note that the 346 needed list can actually grow while we are stepping through this 347 loop. */ 348 needed = bfd_elf_get_needed_list (output_bfd, &link_info); 349 for (l = needed; l != NULL; l = l->next) 350 { 351 struct bfd_link_needed_list *ll; 352 int force; 353 354 /* If we've already seen this file, skip it. */ 355 for (ll = needed; ll != l; ll = ll->next) 356 if (strcmp (ll->name, l->name) == 0) 357 break; 358 if (ll != l) 359 continue; 360 361 /* See if this file was included in the link explicitly. */ 362 global_needed = l; 363 global_found = false; 364 lang_for_each_input_file (gld${EMULATION_NAME}_check_needed); 365 if (global_found) 366 continue; 367 368 /* We need to find this file and include the symbol table. We 369 want to search for the file in the same way that the dynamic 370 linker will search. That means that we want to use 371 rpath_link, rpath, then the environment variable 372 LD_LIBRARY_PATH (native only), then the linker script 373 LIB_SEARCH_DIRS. We do not search using the -L arguments. 374 375 We search twice. The first time, we skip objects which may 376 introduce version mismatches. The second time, we force 377 their use. See gld${EMULATION_NAME}_vercheck comment. */ 378 for (force = 0; force < 2; force++) 379 { 380 const char *lib_path; 381 size_t len; 382 search_dirs_type *search; 383 384 if (gld${EMULATION_NAME}_search_needed (command_line.rpath_link, 385 l->name, force)) 386 break; 387 if (gld${EMULATION_NAME}_search_needed (command_line.rpath, 388 l->name, force)) 389 break; 390 if (command_line.rpath_link == NULL 391 && command_line.rpath == NULL) 392 { 393 lib_path = (const char *) getenv ("LD_RUN_PATH"); 394 if (gld${EMULATION_NAME}_search_needed (lib_path, l->name, 395 force)) 396 break; 397 } 398EOF 399if [ "x${host}" = "x${target}" ] ; then 400 case " ${EMULATION_LIBPATH} " in 401 *" ${EMULATION_NAME} "*) 402cat >>e${EMULATION_NAME}.c <<EOF 403 lib_path = (const char *) getenv ("LD_LIBRARY_PATH"); 404 if (gld${EMULATION_NAME}_search_needed (lib_path, l->name, force)) 405 break; 406EOF 407 ;; 408 esac 409fi 410cat >>e${EMULATION_NAME}.c <<EOF 411 len = strlen (l->name); 412 for (search = search_head; search != NULL; search = search->next) 413 { 414 char *filename; 415 416 if (search->cmdline) 417 continue; 418 filename = (char *) xmalloc (strlen (search->name) + len + 2); 419 sprintf (filename, "%s/%s", search->name, l->name); 420 if (gld${EMULATION_NAME}_try_needed (filename, force)) 421 break; 422 free (filename); 423 } 424 if (search != NULL) 425 break; 426EOF 427if [ "x${host}" = "x${target}" ] ; then 428 case " ${EMULATION_LIBPATH} " in 429 *" ${EMULATION_NAME} "*) 430 case ${target} in 431 *-*-freebsd*) 432 cat >>e${EMULATION_NAME}.c <<EOF 433 if (gld${EMULATION_NAME}_check_ld_elf_hints (l->name, force)) 434 break; 435EOF 436 ;; 437 *linux*|*Linux*|*LINUX*) 438 cat >>e${EMULATION_NAME}.c <<EOF 439 if (gld${EMULATION_NAME}_check_ld_so_conf (l->name, force)) 440 break; 441EOF 442 ;; 443 esac 444 ;; 445 esac 446fi 447cat >>e${EMULATION_NAME}.c <<EOF 448 } 449 450 if (force < 2) 451 continue; 452 453 einfo ("%P: warning: %s, needed by %B, not found (try using -rpath or -rpath-link)\n", 454 l->name, l->by); 455 } 456} 457 458/* Search for a needed file in a path. */ 459 460static boolean 461gld${EMULATION_NAME}_search_needed (path, name, force) 462 const char *path; 463 const char *name; 464 int force; 465{ 466 const char *s; 467 size_t len; 468 469 if (path == NULL || *path == '\0') 470 return false; 471 len = strlen (name); 472 while (1) 473 { 474 char *filename, *sset; 475 476 s = strchr (path, ':'); 477 if (s == NULL) 478 s = path + strlen (path); 479 480 filename = (char *) xmalloc (s - path + len + 2); 481 if (s == path) 482 sset = filename; 483 else 484 { 485 memcpy (filename, path, s - path); 486 filename[s - path] = '/'; 487 sset = filename + (s - path) + 1; 488 } 489 strcpy (sset, name); 490 491 if (gld${EMULATION_NAME}_try_needed (filename, force)) 492 return true; 493 494 free (filename); 495 496 if (*s == '\0') 497 break; 498 path = s + 1; 499 } 500 501 return false; 502} 503 504/* This function is called for each possible name for a dynamic object 505 named by a DT_NEEDED entry. The FORCE parameter indicates whether 506 to skip the check for a conflicting version. */ 507 508static boolean 509gld${EMULATION_NAME}_try_needed (name, force) 510 const char *name; 511 int force; 512{ 513 bfd *abfd; 514 515 abfd = bfd_openr (name, bfd_get_target (output_bfd)); 516 if (abfd == NULL) 517 return false; 518 if (! bfd_check_format (abfd, bfd_object)) 519 { 520 (void) bfd_close (abfd); 521 return false; 522 } 523 if ((bfd_get_file_flags (abfd) & DYNAMIC) == 0) 524 { 525 (void) bfd_close (abfd); 526 return false; 527 } 528 529 /* Check whether this object would include any conflicting library 530 versions. If FORCE is set, then we skip this check; we use this 531 the second time around, if we couldn't find any compatible 532 instance of the shared library. */ 533 534 if (! force) 535 { 536 struct bfd_link_needed_list *needed; 537 538 if (! bfd_elf_get_bfd_needed_list (abfd, &needed)) 539 einfo ("%F%P:%B: bfd_elf_get_bfd_needed_list failed: %E\n", abfd); 540 541 if (needed != NULL) 542 { 543 global_vercheck_needed = needed; 544 global_vercheck_failed = false; 545 lang_for_each_input_file (gld${EMULATION_NAME}_vercheck); 546 if (global_vercheck_failed) 547 { 548 (void) bfd_close (abfd); 549 /* Return false to force the caller to move on to try 550 another file on the search path. */ 551 return false; 552 } 553 554 /* But wait! It gets much worse. On Linux, if a shared 555 library does not use libc at all, we are supposed to skip 556 it the first time around in case we encounter a shared 557 library later on with the same name which does use the 558 version of libc that we want. This is much too horrible 559 to use on any system other than Linux. */ 560 561EOF 562case ${target} in 563 *-*-linux-gnu*) 564 cat >>e${EMULATION_NAME}.c <<EOF 565 { 566 struct bfd_link_needed_list *l; 567 568 for (l = needed; l != NULL; l = l->next) 569 if (strncmp (l->name, "libc.so", 7) == 0) 570 break; 571 if (l == NULL) 572 { 573 (void) bfd_close (abfd); 574 return false; 575 } 576 } 577 578EOF 579 ;; 580esac 581cat >>e${EMULATION_NAME}.c <<EOF 582 } 583 } 584 585 /* We've found a dynamic object matching the DT_NEEDED entry. */ 586 587 /* We have already checked that there is no other input file of the 588 same name. We must now check again that we are not including the 589 same file twice. We need to do this because on many systems 590 libc.so is a symlink to, e.g., libc.so.1. The SONAME entry will 591 reference libc.so.1. If we have already included libc.so, we 592 don't want to include libc.so.1 if they are the same file, and we 593 can only check that using stat. */ 594 595 if (bfd_stat (abfd, &global_stat) != 0) 596 einfo ("%F%P:%B: bfd_stat failed: %E\n", abfd); 597 global_found = false; 598 lang_for_each_input_file (gld${EMULATION_NAME}_stat_needed); 599 if (global_found) 600 { 601 /* Return true to indicate that we found the file, even though 602 we aren't going to do anything with it. */ 603 return true; 604 } 605 606 /* Tell the ELF backend that don't want the output file to have a 607 DT_NEEDED entry for this file. */ 608 bfd_elf_set_dt_needed_name (abfd, ""); 609 610 /* Add this file into the symbol table. */ 611 if (! bfd_link_add_symbols (abfd, &link_info)) 612 einfo ("%F%B: could not read symbols: %E\n", abfd); 613 614 return true; 615} 616 617/* See if an input file matches a DT_NEEDED entry by name. */ 618 619static void 620gld${EMULATION_NAME}_check_needed (s) 621 lang_input_statement_type *s; 622{ 623 if (global_found) 624 return; 625 626 if (s->filename != NULL 627 && strcmp (s->filename, global_needed->name) == 0) 628 { 629 global_found = true; 630 return; 631 } 632 633 if (s->the_bfd != NULL) 634 { 635 const char *soname; 636 637 soname = bfd_elf_get_dt_soname (s->the_bfd); 638 if (soname != NULL 639 && strcmp (soname, global_needed->name) == 0) 640 { 641 global_found = true; 642 return; 643 } 644 } 645 646 if (s->search_dirs_flag 647 && s->filename != NULL 648 && strchr (global_needed->name, '/') == NULL) 649 { 650 const char *f; 651 652 f = strrchr (s->filename, '/'); 653 if (f != NULL 654 && strcmp (f + 1, global_needed->name) == 0) 655 { 656 global_found = true; 657 return; 658 } 659 } 660} 661 662/* See if an input file matches a DT_NEEDED entry by running stat on 663 the file. */ 664 665static void 666gld${EMULATION_NAME}_stat_needed (s) 667 lang_input_statement_type *s; 668{ 669 struct stat st; 670 const char *suffix; 671 const char *soname; 672 const char *f; 673 674 if (global_found) 675 return; 676 if (s->the_bfd == NULL) 677 return; 678 679 if (bfd_stat (s->the_bfd, &st) != 0) 680 { 681 einfo ("%P:%B: bfd_stat failed: %E\n", s->the_bfd); 682 return; 683 } 684 685 if (st.st_dev == global_stat.st_dev 686 && st.st_ino == global_stat.st_ino) 687 { 688 global_found = true; 689 return; 690 } 691 692 /* We issue a warning if it looks like we are including two 693 different versions of the same shared library. For example, 694 there may be a problem if -lc picks up libc.so.6 but some other 695 shared library has a DT_NEEDED entry of libc.so.5. This is a 696 hueristic test, and it will only work if the name looks like 697 NAME.so.VERSION. FIXME: Depending on file names is error-prone. 698 If we really want to issue warnings about mixing version numbers 699 of shared libraries, we need to find a better way. */ 700 701 if (strchr (global_needed->name, '/') != NULL) 702 return; 703 suffix = strstr (global_needed->name, ".so."); 704 if (suffix == NULL) 705 return; 706 suffix += sizeof ".so." - 1; 707 708 soname = bfd_elf_get_dt_soname (s->the_bfd); 709 if (soname == NULL) 710 soname = s->filename; 711 712 f = strrchr (soname, '/'); 713 if (f != NULL) 714 ++f; 715 else 716 f = soname; 717 718 if (strncmp (f, global_needed->name, suffix - global_needed->name) == 0) 719 einfo ("%P: warning: %s, needed by %B, may conflict with %s\n", 720 global_needed->name, global_needed->by, f); 721} 722 723/* On Linux, it's possible to have different versions of the same 724 shared library linked against different versions of libc. The 725 dynamic linker somehow tags which libc version to use in 726 /etc/ld.so.cache, and, based on the libc that it sees in the 727 executable, chooses which version of the shared library to use. 728 729 We try to do a similar check here by checking whether this shared 730 library needs any other shared libraries which may conflict with 731 libraries we have already included in the link. If it does, we 732 skip it, and try to find another shared library farther on down the 733 link path. 734 735 This is called via lang_for_each_input_file. 736 GLOBAL_VERCHECK_NEEDED is the list of objects needed by the object 737 which we ar checking. This sets GLOBAL_VERCHECK_FAILED if we find 738 a conflicting version. */ 739 740static void 741gld${EMULATION_NAME}_vercheck (s) 742 lang_input_statement_type *s; 743{ 744 const char *soname, *f; 745 struct bfd_link_needed_list *l; 746 747 if (global_vercheck_failed) 748 return; 749 if (s->the_bfd == NULL 750 || (bfd_get_file_flags (s->the_bfd) & DYNAMIC) == 0) 751 return; 752 753 soname = bfd_elf_get_dt_soname (s->the_bfd); 754 if (soname == NULL) 755 soname = bfd_get_filename (s->the_bfd); 756 757 f = strrchr (soname, '/'); 758 if (f != NULL) 759 ++f; 760 else 761 f = soname; 762 763 for (l = global_vercheck_needed; l != NULL; l = l->next) 764 { 765 const char *suffix; 766 767 if (strcmp (f, l->name) == 0) 768 { 769 /* Probably can't happen, but it's an easy check. */ 770 continue; 771 } 772 773 if (strchr (l->name, '/') != NULL) 774 continue; 775 776 suffix = strstr (l->name, ".so."); 777 if (suffix == NULL) 778 continue; 779 780 suffix += sizeof ".so." - 1; 781 782 if (strncmp (f, l->name, suffix - l->name) == 0) 783 { 784 /* Here we know that S is a dynamic object FOO.SO.VER1, and 785 the object we are considering needs a dynamic object 786 FOO.SO.VER2, and VER1 and VER2 are different. This 787 appears to be a version mismatch, so we tell the caller 788 to try a different version of this library. */ 789 global_vercheck_failed = true; 790 return; 791 } 792 } 793} 794 795/* This is called after the sections have been attached to output 796 sections, but before any sizes or addresses have been set. */ 797 798static void 799gld${EMULATION_NAME}_before_allocation () 800{ 801 const char *rpath; 802 asection *sinterp; 803 804 /* If we are going to make any variable assignments, we need to let 805 the ELF backend know about them in case the variables are 806 referred to by dynamic objects. */ 807 lang_for_each_statement (gld${EMULATION_NAME}_find_statement_assignment); 808 809 /* Let the ELF backend work out the sizes of any sections required 810 by dynamic linking. */ 811 rpath = command_line.rpath; 812 if (rpath == NULL) 813 rpath = (const char *) getenv ("LD_RUN_PATH"); 814 if (! (bfd_elf${ELFSIZE}_size_dynamic_sections 815 (output_bfd, command_line.soname, rpath, 816 command_line.export_dynamic, command_line.filter_shlib, 817 (const char * const *) command_line.auxiliary_filters, 818 &link_info, &sinterp, lang_elf_version_info))) 819 einfo ("%P%F: failed to set dynamic section sizes: %E\n"); 820 821 /* Let the user override the dynamic linker we are using. */ 822 if (command_line.interpreter != NULL 823 && sinterp != NULL) 824 { 825 sinterp->contents = (bfd_byte *) command_line.interpreter; 826 sinterp->_raw_size = strlen (command_line.interpreter) + 1; 827 } 828 829 /* Look for any sections named .gnu.warning. As a GNU extensions, 830 we treat such sections as containing warning messages. We print 831 out the warning message, and then zero out the section size so 832 that it does not get copied into the output file. */ 833 834 { 835 LANG_FOR_EACH_INPUT_STATEMENT (is) 836 { 837 asection *s; 838 bfd_size_type sz; 839 char *msg; 840 boolean ret; 841 842 if (is->just_syms_flag) 843 continue; 844 845 s = bfd_get_section_by_name (is->the_bfd, ".gnu.warning"); 846 if (s == NULL) 847 continue; 848 849 sz = bfd_section_size (is->the_bfd, s); 850 msg = xmalloc ((size_t) sz + 1); 851 if (! bfd_get_section_contents (is->the_bfd, s, msg, (file_ptr) 0, sz)) 852 einfo ("%F%B: Can't read contents of section .gnu.warning: %E\n", 853 is->the_bfd); 854 msg[sz] = '\0'; 855 ret = link_info.callbacks->warning (&link_info, msg, 856 (const char *) NULL, 857 is->the_bfd, (asection *) NULL, 858 (bfd_vma) 0); 859 ASSERT (ret); 860 free (msg); 861 862 /* Clobber the section size, so that we don't waste copying the 863 warning into the output file. */ 864 s->_raw_size = 0; 865 } 866 } 867} 868 869/* This is called by the before_allocation routine via 870 lang_for_each_statement. It locates any assignment statements, and 871 tells the ELF backend about them, in case they are assignments to 872 symbols which are referred to by dynamic objects. */ 873 874static void 875gld${EMULATION_NAME}_find_statement_assignment (s) 876 lang_statement_union_type *s; 877{ 878 if (s->header.type == lang_assignment_statement_enum) 879 gld${EMULATION_NAME}_find_exp_assignment (s->assignment_statement.exp); 880} 881 882/* Look through an expression for an assignment statement. */ 883 884static void 885gld${EMULATION_NAME}_find_exp_assignment (exp) 886 etree_type *exp; 887{ 888 struct bfd_link_hash_entry *h; 889 890 switch (exp->type.node_class) 891 { 892 case etree_provide: 893 h = bfd_link_hash_lookup (link_info.hash, exp->assign.dst, 894 false, false, false); 895 if (h == NULL) 896 break; 897 898 /* We call record_link_assignment even if the symbol is defined. 899 This is because if it is defined by a dynamic object, we 900 actually want to use the value defined by the linker script, 901 not the value from the dynamic object (because we are setting 902 symbols like etext). If the symbol is defined by a regular 903 object, then, as it happens, calling record_link_assignment 904 will do no harm. */ 905 906 /* Fall through. */ 907 case etree_assign: 908 if (strcmp (exp->assign.dst, ".") != 0) 909 { 910 if (! (bfd_elf${ELFSIZE}_record_link_assignment 911 (output_bfd, &link_info, exp->assign.dst, 912 exp->type.node_class == etree_provide ? true : false))) 913 einfo ("%P%F: failed to record assignment to %s: %E\n", 914 exp->assign.dst); 915 } 916 gld${EMULATION_NAME}_find_exp_assignment (exp->assign.src); 917 break; 918 919 case etree_binary: 920 gld${EMULATION_NAME}_find_exp_assignment (exp->binary.lhs); 921 gld${EMULATION_NAME}_find_exp_assignment (exp->binary.rhs); 922 break; 923 924 case etree_trinary: 925 gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.cond); 926 gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.lhs); 927 gld${EMULATION_NAME}_find_exp_assignment (exp->trinary.rhs); 928 break; 929 930 case etree_unary: 931 gld${EMULATION_NAME}_find_exp_assignment (exp->unary.child); 932 break; 933 934 default: 935 break; 936 } 937} 938 939/* A variant of lang_output_section_find. Used by place_orphan. */ 940 941static lang_output_section_statement_type * 942output_rel_find () 943{ 944 lang_statement_union_type *u; 945 lang_output_section_statement_type *lookup; 946 947 for (u = lang_output_section_statement.head; 948 u != (lang_statement_union_type *) NULL; 949 u = lookup->next) 950 { 951 lookup = &u->output_section_statement; 952 if (strncmp (".rel", lookup->name, 4) == 0 953 && lookup->bfd_section != NULL 954 && (lookup->bfd_section->flags & SEC_ALLOC) != 0) 955 { 956 return lookup; 957 } 958 } 959 return (lang_output_section_statement_type *) NULL; 960} 961 962/* Place an orphan section. We use this to put random SHF_ALLOC 963 sections in the right segment. */ 964 965struct orphan_save { 966 lang_output_section_statement_type *os; 967 asection **section; 968 lang_statement_union_type **stmt; 969}; 970 971static boolean 972gld${EMULATION_NAME}_place_orphan (file, s) 973 lang_input_statement_type *file; 974 asection *s; 975{ 976 static struct orphan_save hold_text; 977 static struct orphan_save hold_rodata; 978 static struct orphan_save hold_data; 979 static struct orphan_save hold_bss; 980 static struct orphan_save hold_rel; 981 static struct orphan_save hold_interp; 982 struct orphan_save *place; 983 lang_statement_list_type *old; 984 lang_statement_list_type add; 985 etree_type *address; 986 const char *secname; 987 const char *outsecname; 988 const char *ps = NULL; 989 lang_output_section_statement_type *os; 990 991 secname = bfd_get_section_name (s->owner, s); 992 993 /* Look through the script to see where to place this section. */ 994 os = lang_output_section_find (secname); 995 996 if (os != NULL 997 && os->bfd_section != NULL 998 && ((s->flags ^ os->bfd_section->flags) & (SEC_LOAD | SEC_ALLOC)) == 0) 999 { 1000 /* We have already placed a section with this name. */ 1001 wild_doit (&os->children, s, os, file); 1002 return true; 1003 } 1004 1005 if (hold_text.os == NULL) 1006 hold_text.os = lang_output_section_find (".text"); 1007 1008 /* If this is a final link, then always put .gnu.warning.SYMBOL 1009 sections into the .text section to get them out of the way. */ 1010 if (! link_info.shared 1011 && ! link_info.relocateable 1012 && strncmp (secname, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0 1013 && hold_text.os != NULL) 1014 { 1015 wild_doit (&hold_text.os->children, s, hold_text.os, file); 1016 return true; 1017 } 1018 1019 /* Decide which segment the section should go in based on the 1020 section name and section flags. We put loadable .note sections 1021 right after the .interp section, so that the PT_NOTE segment is 1022 stored right after the program headers where the OS can read it 1023 in the first page. */ 1024#define HAVE_SECTION(hold, name) \ 1025(hold.os != NULL || (hold.os = lang_output_section_find (name)) != NULL) 1026 1027 if (s->flags & SEC_EXCLUDE) 1028 return false; 1029 1030 place = NULL; 1031 if ((s->flags & SEC_ALLOC) == 0) 1032 ; 1033 else if ((s->flags & SEC_LOAD) != 0 1034 && strncmp (secname, ".note", 4) == 0 1035 && HAVE_SECTION (hold_interp, ".interp")) 1036 place = &hold_interp; 1037 else if ((s->flags & SEC_HAS_CONTENTS) == 0 1038 && HAVE_SECTION (hold_bss, ".bss")) 1039 place = &hold_bss; 1040 else if ((s->flags & SEC_READONLY) == 0 1041 && HAVE_SECTION (hold_data, ".data")) 1042 place = &hold_data; 1043 else if (strncmp (secname, ".rel", 4) == 0 1044 && (hold_rel.os != NULL 1045 || (hold_rel.os = output_rel_find ()) != NULL)) 1046 place = &hold_rel; 1047 else if ((s->flags & (SEC_CODE | SEC_READONLY)) == SEC_READONLY 1048 && HAVE_SECTION (hold_rodata, ".rodata")) 1049 place = &hold_rodata; 1050 else if ((s->flags & (SEC_CODE | SEC_READONLY)) == (SEC_CODE | SEC_READONLY) 1051 && hold_text.os != NULL) 1052 place = &hold_text; 1053 1054#undef HAVE_SECTION 1055 1056 /* Choose a unique name for the section. This will be needed if the 1057 same section name appears in the input file with different 1058 loadable or allocateable characteristics. */ 1059 outsecname = secname; 1060 if (bfd_get_section_by_name (output_bfd, outsecname) != NULL) 1061 { 1062 unsigned int len; 1063 char *newname; 1064 unsigned int i; 1065 1066 len = strlen (outsecname); 1067 newname = xmalloc (len + 5); 1068 strcpy (newname, outsecname); 1069 i = 0; 1070 do 1071 { 1072 sprintf (newname + len, "%d", i); 1073 ++i; 1074 } 1075 while (bfd_get_section_by_name (output_bfd, newname) != NULL); 1076 1077 outsecname = newname; 1078 } 1079 1080 /* Start building a list of statements for this section. 1081 First save the current statement pointer. */ 1082 old = stat_ptr; 1083 1084 /* If we have found an appropriate place for the output section 1085 statements for this orphan, add them to our own private list, 1086 inserting them later into the global statement list. */ 1087 if (place != NULL) 1088 { 1089 stat_ptr = &add; 1090 lang_list_init (stat_ptr); 1091 } 1092 1093 if (config.build_constructors) 1094 { 1095 /* If the name of the section is representable in C, then create 1096 symbols to mark the start and the end of the section. */ 1097 for (ps = outsecname; *ps != '\0'; ps++) 1098 if (! isalnum ((unsigned char) *ps) && *ps != '_') 1099 break; 1100 if (*ps == '\0') 1101 { 1102 char *symname; 1103 etree_type *e_align; 1104 1105 symname = (char *) xmalloc (ps - outsecname + sizeof "__start_"); 1106 sprintf (symname, "__start_%s", outsecname); 1107 e_align = exp_unop (ALIGN_K, 1108 exp_intop ((bfd_vma) 1 << s->alignment_power)); 1109 lang_add_assignment (exp_assop ('=', symname, e_align)); 1110 } 1111 } 1112 1113 if (link_info.relocateable || (s->flags & (SEC_LOAD | SEC_ALLOC)) == 0) 1114 address = exp_intop ((bfd_vma) 0); 1115 else 1116 address = NULL; 1117 1118 os = lang_enter_output_section_statement (outsecname, address, 0, 1119 (bfd_vma) 0, 1120 (etree_type *) NULL, 1121 (etree_type *) NULL, 1122 (etree_type *) NULL); 1123 1124 wild_doit (&os->children, s, os, file); 1125 1126 lang_leave_output_section_statement 1127 ((bfd_vma) 0, "*default*", 1128 (struct lang_output_section_phdr_list *) NULL, "*default*"); 1129 1130 if (config.build_constructors && *ps == '\0') 1131 { 1132 char *symname; 1133 1134 /* lang_leave_ouput_section_statement resets stat_ptr. Put 1135 stat_ptr back where we want it. */ 1136 if (place != NULL) 1137 stat_ptr = &add; 1138 1139 symname = (char *) xmalloc (ps - outsecname + sizeof "__stop_"); 1140 sprintf (symname, "__stop_%s", outsecname); 1141 lang_add_assignment (exp_assop ('=', symname, 1142 exp_nameop (NAME, "."))); 1143 } 1144 1145 /* Restore the global list pointer. */ 1146 stat_ptr = old; 1147 1148 if (place != NULL) 1149 { 1150 asection *snew, **pps; 1151 1152 snew = os->bfd_section; 1153 if (place->section != NULL 1154 || (place->os->bfd_section != NULL 1155 && place->os->bfd_section != snew)) 1156 { 1157 /* Shuffle the section to make the output file look neater. 1158 This is really only cosmetic. */ 1159 if (place->section == NULL) 1160 { 1161#if 0 1162 /* Finding the end of the list is a little tricky. We 1163 make a wild stab at it by comparing section flags. */ 1164 flagword first_flags = place->os->bfd_section->flags; 1165 for (pps = &place->os->bfd_section->next; 1166 *pps != NULL && (*pps)->flags == first_flags; 1167 pps = &(*pps)->next) 1168 ; 1169 place->section = pps; 1170#else 1171 /* Put orphans after the first section on the list. */ 1172 place->section = &place->os->bfd_section->next; 1173#endif 1174 } 1175 1176 /* Unlink the section. */ 1177 for (pps = &output_bfd->sections; *pps != snew; pps = &(*pps)->next) 1178 ; 1179 *pps = snew->next; 1180 1181 /* Now tack it on to the "place->os" section list. */ 1182 snew->next = *place->section; 1183 *place->section = snew; 1184 } 1185 place->section = &snew->next; /* Save the end of this list. */ 1186 1187 if (add.head != NULL) 1188 { 1189 /* We try to put the output statements in some sort of 1190 reasonable order here, because they determine the final 1191 load addresses of the orphan sections. */ 1192 if (place->stmt == NULL) 1193 { 1194 /* Put the new statement list right at the head. */ 1195 *add.tail = place->os->header.next; 1196 place->os->header.next = add.head; 1197 } 1198 else 1199 { 1200 /* Put it after the last orphan statement we added. */ 1201 *add.tail = *place->stmt; 1202 *place->stmt = add.head; 1203 } 1204 1205 /* Fix the global list pointer if we happened to tack our 1206 new list at the tail. */ 1207 if (*old->tail == add.head) 1208 old->tail = add.tail; 1209 1210 /* Save the end of this list. */ 1211 place->stmt = add.tail; 1212 } 1213 } 1214 1215 return true; 1216} 1217 1218static char * 1219gld${EMULATION_NAME}_get_script(isfile) 1220 int *isfile; 1221EOF 1222 1223if test -n "$COMPILE_IN" 1224then 1225# Scripts compiled in. 1226 1227# sed commands to quote an ld script as a C string. 1228sc="-f stringify.sed" 1229 1230cat >>e${EMULATION_NAME}.c <<EOF 1231{ 1232 *isfile = 0; 1233 1234 if (link_info.relocateable == true && config.build_constructors == true) 1235 return 1236EOF 1237sed $sc ldscripts/${EMULATION_NAME}.xu >> e${EMULATION_NAME}.c 1238echo ' ; else if (link_info.relocateable == true) return' >> e${EMULATION_NAME}.c 1239sed $sc ldscripts/${EMULATION_NAME}.xr >> e${EMULATION_NAME}.c 1240echo ' ; else if (!config.text_read_only) return' >> e${EMULATION_NAME}.c 1241sed $sc ldscripts/${EMULATION_NAME}.xbn >> e${EMULATION_NAME}.c 1242echo ' ; else if (!config.magic_demand_paged) return' >> e${EMULATION_NAME}.c 1243sed $sc ldscripts/${EMULATION_NAME}.xn >> e${EMULATION_NAME}.c 1244 1245if test -n "$GENERATE_SHLIB_SCRIPT" ; then 1246echo ' ; else if (link_info.shared) return' >> e${EMULATION_NAME}.c 1247sed $sc ldscripts/${EMULATION_NAME}.xs >> e${EMULATION_NAME}.c 1248fi 1249 1250echo ' ; else return' >> e${EMULATION_NAME}.c 1251sed $sc ldscripts/${EMULATION_NAME}.x >> e${EMULATION_NAME}.c 1252echo '; }' >> e${EMULATION_NAME}.c 1253 1254else 1255# Scripts read from the filesystem. 1256 1257cat >>e${EMULATION_NAME}.c <<EOF 1258{ 1259 *isfile = 1; 1260 1261 if (link_info.relocateable == true && config.build_constructors == true) 1262 return "ldscripts/${EMULATION_NAME}.xu"; 1263 else if (link_info.relocateable == true) 1264 return "ldscripts/${EMULATION_NAME}.xr"; 1265 else if (!config.text_read_only) 1266 return "ldscripts/${EMULATION_NAME}.xbn"; 1267 else if (!config.magic_demand_paged) 1268 return "ldscripts/${EMULATION_NAME}.xn"; 1269 else if (link_info.shared) 1270 return "ldscripts/${EMULATION_NAME}.xs"; 1271 else 1272 return "ldscripts/${EMULATION_NAME}.x"; 1273} 1274EOF 1275 1276fi 1277 1278if test -n "$PARSE_AND_LIST_ARGS" ; then 1279cat >>e${EMULATION_NAME}.c <<EOF 1280static int gld_${EMULATION_NAME}_parse_args PARAMS ((int, char **)); 1281static void gld_${EMULATION_NAME}_list_options PARAMS ((FILE * file)); 1282 1283 $PARSE_AND_LIST_ARGS 1284EOF 1285else 1286 1287cat >>e${EMULATION_NAME}.c <<EOF 1288#define gld_${EMULATION_NAME}_parse_args NULL 1289#define gld_${EMULATION_NAME}_list_options NULL 1290EOF 1291 1292fi 1293 1294cat >>e${EMULATION_NAME}.c <<EOF 1295 1296struct ld_emulation_xfer_struct ld_${EMULATION_NAME}_emulation = 1297{ 1298 gld${EMULATION_NAME}_before_parse, 1299 syslib_default, 1300 hll_default, 1301 after_parse_default, 1302 gld${EMULATION_NAME}_after_open, 1303 after_allocation_default, 1304 set_output_arch_default, 1305 ldemul_default_target, 1306 gld${EMULATION_NAME}_before_allocation, 1307 gld${EMULATION_NAME}_get_script, 1308 "${EMULATION_NAME}", 1309 "${OUTPUT_FORMAT}", 1310 NULL, /* finish */ 1311 NULL, /* create output section statements */ 1312 gld${EMULATION_NAME}_open_dynamic_archive, 1313 gld${EMULATION_NAME}_place_orphan, 1314 NULL, /* set_symbols */ 1315 gld_${EMULATION_NAME}_parse_args, 1316 NULL, /* unrecognized_file */ 1317 gld_${EMULATION_NAME}_list_options, 1318 NULL, /* recognized_file */ 1319 NULL /* find_potential_libraries */ 1320}; 1321EOF 1322