ld/ldmain.c

   1 /* Main program of GNU linker.
   2    Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000
   3    Free Software Foundation, Inc.
   4    Written by Steve Chamberlain steve@cygnus.com
   5
   6 This file is part of GLD, the Gnu Linker.
   7
   8 GLD is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2, or (at your option)
  11 any later version.
  12
  13 GLD is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GLD; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  21 02111-1307, USA.  */
  22
  23 #include "bfd.h"
  24 #include "sysdep.h"
  25 #include <stdio.h>
  26 #include <ctype.h>
  27 #include "libiberty.h"
  28 #include "progress.h"
  29 #include "bfdlink.h"
  30 #include "filenames.h"
  31
  32 #include "ld.h"
  33 #include "ldmain.h"
  34 #include "ldmisc.h"
  35 #include "ldwrite.h"
  36 #include "ldgram.h"
  37 #include "ldexp.h"
  38 #include "ldlang.h"
  39 #include "ldlex.h"
  40 #include "ldfile.h"
  41 #include "ldemul.h"
  42 #include "ldctor.h"
  43
  44 /* Somewhere above, sys/stat.h got included . . . .  */
  45 #if !defined(S_ISDIR) && defined(S_IFDIR)
  46 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  47 #endif
  48
  49 #include <string.h>
  50
  51 #ifdef HAVE_SBRK
  52 #ifdef NEED_DECLARATION_SBRK
  53 extern PTR sbrk ();
  54 #endif
  55 #endif
  56
  57 static char *get_emulation PARAMS ((int, char **));
  58 static void set_scripts_dir PARAMS ((void));
  59
  60 /* EXPORTS */
  61
  62 char *default_target;
  63 const char *output_filename = "a.out";
  64
  65 /* Name this program was invoked by.  */
  66 char *program_name;
  67
  68 /* The file that we're creating.  */
  69 bfd *output_bfd = 0;
  70
  71 /* Set by -G argument, for MIPS ECOFF target.  */
  72 int g_switch_value = 8;
  73
  74 /* Nonzero means print names of input files as processed.  */
  75 boolean trace_files;
  76
  77 /* Nonzero means same, but note open failures, too.  */
  78 boolean trace_file_tries;
  79
  80 /* Nonzero means version number was printed, so exit successfully
  81    instead of complaining if no input files are given.  */
  82 boolean version_printed;
  83
  84 /* Nonzero means link in every member of an archive.  */
  85 boolean whole_archive;
  86
  87 /* True if we should demangle symbol names.  */
  88 boolean demangling;
  89
  90 args_type command_line;
  91
  92 ld_config_type config;
  93
  94 static void remove_output PARAMS ((void));
  95 static boolean check_for_scripts_dir PARAMS ((char *dir));
  96 static boolean add_archive_element PARAMS ((struct bfd_link_info *, bfd *,
  97                                             const char *));
  98 static boolean multiple_definition PARAMS ((struct bfd_link_info *,
  99                                             const char *,
 100                                             bfd *, asection *, bfd_vma,
 101                                             bfd *, asection *, bfd_vma));
 102 static boolean multiple_common PARAMS ((struct bfd_link_info *,
 103                                         const char *, bfd *,
 104                                         enum bfd_link_hash_type, bfd_vma,
 105                                         bfd *, enum bfd_link_hash_type,
 106                                         bfd_vma));
 107 static boolean add_to_set PARAMS ((struct bfd_link_info *,
 108                                    struct bfd_link_hash_entry *,
 109                                    bfd_reloc_code_real_type,
 110                                    bfd *, asection *, bfd_vma));
 111 static boolean constructor_callback PARAMS ((struct bfd_link_info *,
 112                                              boolean constructor,
 113                                              const char *name,
 114                                              bfd *, asection *, bfd_vma));
 115 static boolean warning_callback PARAMS ((struct bfd_link_info *,
 116                                          const char *, const char *, bfd *,
 117                                          asection *, bfd_vma));
 118 static void warning_find_reloc PARAMS ((bfd *, asection *, PTR));
 119 static boolean undefined_symbol PARAMS ((struct bfd_link_info *,
 120                                          const char *, bfd *,
 121                                          asection *, bfd_vma, boolean));
 122 static boolean reloc_overflow PARAMS ((struct bfd_link_info *, const char *,
 123                                        const char *, bfd_vma,
 124                                        bfd *, asection *, bfd_vma));
 125 static boolean reloc_dangerous PARAMS ((struct bfd_link_info *, const char *,
 126                                         bfd *, asection *, bfd_vma));
 127 static boolean unattached_reloc PARAMS ((struct bfd_link_info *,
 128                                          const char *, bfd *, asection *,
 129                                          bfd_vma));
 130 static boolean notice PARAMS ((struct bfd_link_info *, const char *,
 131                                bfd *, asection *, bfd_vma));
 132
 133 static struct bfd_link_callbacks link_callbacks = {
 134   add_archive_element,
 135   multiple_definition,
 136   multiple_common,
 137   add_to_set,
 138   constructor_callback,
 139   warning_callback,
 140   undefined_symbol,
 141   reloc_overflow,
 142   reloc_dangerous,
 143   unattached_reloc,
 144   notice
 145 };
 146
 147 struct bfd_link_info link_info;
 148 \f
 149 static void
 150 remove_output ()
 151 {
 152   if (output_filename)
 153     {
 154       if (output_bfd && output_bfd->iostream)
 155         fclose ((FILE *) (output_bfd->iostream));
 156       if (delete_output_file_on_failure)
 157         unlink (output_filename);
 158     }
 159 }
 160
 161 int
 162 main (argc, argv)
 163      int argc;
 164      char **argv;
 165 {
 166   char *emulation;
 167   long start_time = get_run_time ();
 168
 169 #if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
 170   setlocale (LC_MESSAGES, "");
 171 #endif
 172   bindtextdomain (PACKAGE, LOCALEDIR);
 173   textdomain (PACKAGE);
 174
 175   program_name = argv[0];
 176   xmalloc_set_program_name (program_name);
 177
 178   START_PROGRESS (program_name, 0);
 179
 180   bfd_init ();
 181
 182   bfd_set_error_program_name (program_name);
 183
 184   xatexit (remove_output);
 185
 186   /* Set the default BFD target based on the configured target.  Doing
 187      this permits the linker to be configured for a particular target,
 188      and linked against a shared BFD library which was configured for
 189      a different target.  The macro TARGET is defined by Makefile.  */
 190   if (! bfd_set_default_target (TARGET))
 191     {
 192       einfo (_("%X%P: can't set BFD default target to `%s': %E\n"), TARGET);
 193       xexit (1);
 194     }
 195
 196   /* Initialize the data about options.  */
 197   trace_files = trace_file_tries = version_printed = false;
 198   whole_archive = false;
 199   config.build_constructors = true;
 200   config.dynamic_link = false;
 201   config.has_shared = false;
 202   config.split_by_reloc = (unsigned) -1;
 203   config.split_by_file = (bfd_size_type) -1;
 204   command_line.force_common_definition = false;
 205   command_line.interpreter = NULL;
 206   command_line.rpath = NULL;
 207   command_line.warn_mismatch = true;
 208   command_line.check_section_addresses = true;
 209
 210   /* We initialize DEMANGLING based on the environment variable
 211      COLLECT_NO_DEMANGLE.  The gcc collect2 program will demangle the
 212      output of the linker, unless COLLECT_NO_DEMANGLE is set in the
 213      environment.  Acting the same way here lets us provide the same
 214      interface by default.  */
 215   demangling = getenv ("COLLECT_NO_DEMANGLE") == NULL;
 216
 217   link_info.callbacks = &link_callbacks;
 218   link_info.relocateable = false;
 219   link_info.emitrelocations = false;
 220   link_info.shared = false;
 221   link_info.symbolic = false;
 222   link_info.export_dynamic = false;
 223   link_info.static_link = false;
 224   link_info.traditional_format = false;
 225   link_info.optimize = false;
 226   link_info.no_undefined = false;
 227   link_info.allow_shlib_undefined = false;
 228   link_info.strip = strip_none;
 229   link_info.discard = discard_sec_merge;
 230   link_info.keep_memory = true;
 231   link_info.input_bfds = NULL;
 232   link_info.create_object_symbols_section = NULL;
 233   link_info.hash = NULL;
 234   link_info.keep_hash = NULL;
 235   link_info.notice_all = false;
 236   link_info.notice_hash = NULL;
 237   link_info.wrap_hash = NULL;
 238   link_info.mpc860c0 = 0;
 239   /* SVR4 linkers seem to set DT_INIT and DT_FINI based on magic _init
 240      and _fini symbols.  We are compatible.  */
 241   link_info.init_function = "_init";
 242   link_info.fini_function = "_fini";
 243   link_info.new_dtags = false;
 244   link_info.flags = (bfd_vma) 0;
 245   link_info.flags_1 = (bfd_vma) 0;
 246
 247   ldfile_add_arch ("");
 248
 249   config.make_executable = true;
 250   force_make_executable = false;
 251   config.magic_demand_paged = true;
 252   config.text_read_only = true;
 253
 254   emulation = get_emulation (argc, argv);
 255   ldemul_choose_mode (emulation);
 256   default_target = ldemul_choose_target ();
 257   lang_init ();
 258   ldemul_before_parse ();
 259   lang_has_input_file = false;
 260   parse_args (argc, argv);
 261
 262   ldemul_set_symbols ();
 263
 264   if (link_info.relocateable)
 265     {
 266       if (command_line.gc_sections)
 267         einfo ("%P%F: --gc-sections and -r may not be used together\n");
 268       if (link_info.mpc860c0)
 269         einfo (_("%P%F: -r and --mpc860c0 may not be used together\n"));
 270       else if (command_line.relax)
 271         einfo (_("%P%F: --relax and -r may not be used together\n"));
 272       if (link_info.shared)
 273         einfo (_("%P%F: -r and -shared may not be used together\n"));
 274     }
 275
 276   /* Treat ld -r -s as ld -r -S -x (i.e., strip all local symbols).  I
 277      don't see how else this can be handled, since in this case we
 278      must preserve all externally visible symbols.  */
 279   if (link_info.relocateable && link_info.strip == strip_all)
 280     {
 281       link_info.strip = strip_debugger;
 282       if (link_info.discard == discard_sec_merge)
 283         link_info.discard = discard_all;
 284     }
 285
 286   /* This essentially adds another -L directory so this must be done after
 287      the -L's in argv have been processed.  */
 288   set_scripts_dir ();
 289
 290   if (had_script == false)
 291     {
 292       /* Read the emulation's appropriate default script.  */
 293       int isfile;
 294       char *s = ldemul_get_script (&isfile);
 295
 296       if (isfile)
 297         ldfile_open_command_file (s);
 298       else
 299         {
 300           if (trace_file_tries)
 301             {
 302               info_msg (_("using internal linker script:\n"));
 303               info_msg ("==================================================\n");
 304               info_msg (s);
 305               info_msg ("\n==================================================\n");
 306             }
 307           lex_string = s;
 308           lex_redirect (s);
 309         }
 310       parser_input = input_script;
 311       yyparse ();
 312       lex_string = NULL;
 313     }
 314
 315   lang_final ();
 316
 317   if (lang_has_input_file == false)
 318     {
 319       if (version_printed)
 320         xexit (0);
 321       einfo (_("%P%F: no input files\n"));
 322     }
 323
 324   if (trace_files)
 325     {
 326       info_msg (_("%P: mode %s\n"), emulation);
 327     }
 328
 329   ldemul_after_parse ();
 330
 331   if (config.map_filename)
 332     {
 333       if (strcmp (config.map_filename, "-") == 0)
 334         {
 335           config.map_file = stdout;
 336         }
 337       else
 338         {
 339           config.map_file = fopen (config.map_filename, FOPEN_WT);
 340           if (config.map_file == (FILE *) NULL)
 341             {
 342               bfd_set_error (bfd_error_system_call);
 343               einfo (_("%P%F: cannot open map file %s: %E\n"),
 344                      config.map_filename);
 345             }
 346         }
 347     }
 348
 349   lang_process ();
 350
 351   /* Print error messages for any missing symbols, for any warning
 352      symbols, and possibly multiple definitions.  */
 353
 354   if (! link_info.relocateable)
 355     {
 356       /* Look for a text section and switch the readonly attribute in it.  */
 357       asection *found = bfd_get_section_by_name (output_bfd, ".text");
 358
 359       if (found != (asection *) NULL)
 360         {
 361           if (config.text_read_only)
 362             found->flags |= SEC_READONLY;
 363           else
 364             found->flags &= ~SEC_READONLY;
 365         }
 366     }
 367
 368   if (link_info.relocateable)
 369     output_bfd->flags &= ~EXEC_P;
 370   else
 371     output_bfd->flags |= EXEC_P;
 372
 373   ldwrite ();
 374
 375   if (config.map_file != NULL)
 376     lang_map ();
 377   if (command_line.cref)
 378     output_cref (config.map_file != NULL ? config.map_file : stdout);
 379   if (nocrossref_list != NULL)
 380     check_nocrossrefs ();
 381
 382   /* Even if we're producing relocateable output, some non-fatal errors should
 383      be reported in the exit status.  (What non-fatal errors, if any, do we
 384      want to ignore for relocateable output?)  */
 385
 386   if (config.make_executable == false && force_make_executable == false)
 387     {
 388       if (trace_files == true)
 389         {
 390           einfo (_("%P: link errors found, deleting executable `%s'\n"),
 391                  output_filename);
 392         }
 393
 394       /* The file will be removed by remove_output.  */
 395
 396       xexit (1);
 397     }
 398   else
 399     {
 400       if (! bfd_close (output_bfd))
 401         einfo (_("%F%B: final close failed: %E\n"), output_bfd);
 402
 403       /* If the --force-exe-suffix is enabled, and we're making an
 404          executable file and it doesn't end in .exe, copy it to one
 405          which does.  */
 406       if (! link_info.relocateable && command_line.force_exe_suffix)
 407         {
 408           int len = strlen (output_filename);
 409           if (len < 4
 410               || (strcasecmp (output_filename + len - 4, ".exe") != 0
 411                   && strcasecmp (output_filename + len - 4, ".dll") != 0))
 412             {
 413               FILE *src;
 414               FILE *dst;
 415               const int bsize = 4096;
 416               char *buf = xmalloc (bsize);
 417               int l;
 418               char *dst_name = xmalloc (len + 5);
 419               strcpy (dst_name, output_filename);
 420               strcat (dst_name, ".exe");
 421               src = fopen (output_filename, FOPEN_RB);
 422               dst = fopen (dst_name, FOPEN_WB);
 423
 424               if (!src)
 425                 einfo (_("%X%P: unable to open for source of copy `%s'\n"), output_filename);
 426               if (!dst)
 427                 einfo (_("%X%P: unable to open for destination of copy `%s'\n"), dst_name);
 428               while ((l = fread (buf, 1, bsize, src)) > 0)
 429                 {
 430                   int done = fwrite (buf, 1, l, dst);
 431                   if (done != l)
 432                     {
 433                       einfo (_("%P: Error writing file `%s'\n"), dst_name);
 434                     }
 435                 }
 436               fclose (src);
 437               if (fclose (dst) == EOF)
 438                 {
 439                   einfo (_("%P: Error closing file `%s'\n"), dst_name);
 440                 }
 441               free (dst_name);
 442               free (buf);
 443             }
 444         }
 445     }
 446
 447   END_PROGRESS (program_name);
 448
 449   if (config.stats)
 450     {
 451 #ifdef HAVE_SBRK
 452       char *lim = (char *) sbrk (0);
 453 #endif
 454       long run_time = get_run_time () - start_time;
 455
 456       fprintf (stderr, _("%s: total time in link: %ld.%06ld\n"),
 457                program_name, run_time / 1000000, run_time % 1000000);
 458 #ifdef HAVE_SBRK
 459       fprintf (stderr, _("%s: data size %ld\n"), program_name,
 460                (long) (lim - (char *) &environ));
 461 #endif
 462     }
 463
 464   /* Prevent remove_output from doing anything, after a successful link.  */
 465   output_filename = NULL;
 466
 467   xexit (0);
 468   return 0;
 469 }
 470
 471 /* We need to find any explicitly given emulation in order to initialize the
 472    state that's needed by the lex&yacc argument parser (parse_args).  */
 473
 474 static char *
 475 get_emulation (argc, argv)
 476      int argc;
 477      char **argv;
 478 {
 479   char *emulation;
 480   int i;
 481
 482   emulation = getenv (EMULATION_ENVIRON);
 483   if (emulation == NULL)
 484     emulation = DEFAULT_EMULATION;
 485
 486   for (i = 1; i < argc; i++)
 487     {
 488       if (!strncmp (argv[i], "-m", 2))
 489         {
 490           if (argv[i][2] == '\0')
 491             {
 492               /* -m EMUL */
 493               if (i < argc - 1)
 494                 {
 495                   emulation = argv[i + 1];
 496                   i++;
 497                 }
 498               else
 499                 {
 500                   einfo (_("%P%F: missing argument to -m\n"));
 501                 }
 502             }
 503           else if (strcmp (argv[i], "-mips1") == 0
 504                    || strcmp (argv[i], "-mips2") == 0
 505                    || strcmp (argv[i], "-mips3") == 0
 506                    || strcmp (argv[i], "-mips4") == 0
 507                    || strcmp (argv[i], "-mips5") == 0)
 508             {
 509               /* FIXME: The arguments -mips1, -mips2 and -mips3 are
 510                  passed to the linker by some MIPS compilers.  They
 511                  generally tell the linker to use a slightly different
 512                  library path.  Perhaps someday these should be
 513                  implemented as emulations; until then, we just ignore
 514                  the arguments and hope that nobody ever creates
 515                  emulations named ips1, ips2 or ips3.  */
 516             }
 517           else if (strcmp (argv[i], "-m486") == 0)
 518             {
 519               /* FIXME: The argument -m486 is passed to the linker on
 520                  some Linux systems.  Hope that nobody creates an
 521                  emulation named 486.  */
 522             }
 523           else
 524             {
 525               /* -mEMUL */
 526               emulation = &argv[i][2];
 527             }
 528         }
 529     }
 530
 531   return emulation;
 532 }
 533
 534 /* If directory DIR contains an "ldscripts" subdirectory,
 535    add DIR to the library search path and return true,
 536    else return false.  */
 537
 538 static boolean
 539 check_for_scripts_dir (dir)
 540      char *dir;
 541 {
 542   size_t dirlen;
 543   char *buf;
 544   struct stat s;
 545   boolean res;
 546
 547   dirlen = strlen (dir);
 548   /* sizeof counts the terminating NUL.  */
 549   buf = (char *) xmalloc (dirlen + sizeof ("/ldscripts"));
 550   sprintf (buf, "%s/ldscripts", dir);
 551
 552   res = stat (buf, &s) == 0 && S_ISDIR (s.st_mode);
 553   free (buf);
 554   if (res)
 555     ldfile_add_library_path (dir, false);
 556   return res;
 557 }
 558
 559 /* Set the default directory for finding script files.
 560    Libraries will be searched for here too, but that's ok.
 561    We look for the "ldscripts" directory in:
 562
 563    SCRIPTDIR (passed from Makefile)
 564    the dir where this program is (for using it from the build tree)
 565    the dir where this program is/../lib (for installing the tool suite elsewhere) */
 566
 567 static void
 568 set_scripts_dir ()
 569 {
 570   char *end, *dir;
 571   size_t dirlen;
 572
 573   if (check_for_scripts_dir (SCRIPTDIR))
 574     /* We've been installed normally.  */
 575     return;
 576
 577   /* Look for "ldscripts" in the dir where our binary is.  */
 578   end = strrchr (program_name, '/');
 579 #ifdef HAVE_DOS_BASED_FILE_SYSTEM
 580   {
 581     /* We could have \foo\bar, or /foo\bar.  */
 582     char *bslash = strrchr (program_name, '\\');
 583     if (end == NULL || (bslash != NULL && bslash > end))
 584       end = bslash;
 585   }
 586 #endif
 587
 588   if (end == NULL)
 589     {
 590       /* Don't look for ldscripts in the current directory.  There is
 591          too much potential for confusion.  */
 592       return;
 593     }
 594
 595   dirlen = end - program_name;
 596   /* Make a copy of program_name in dir.
 597      Leave room for later "/../lib".  */
 598   dir = (char *) xmalloc (dirlen + 8);
 599   strncpy (dir, program_name, dirlen);
 600   dir[dirlen] = '\0';
 601
 602   if (check_for_scripts_dir (dir))
 603     /* Don't free dir.  */
 604     return;
 605
 606   /* Look for "ldscripts" in <the dir where our binary is>/../lib.  */
 607   strcpy (dir + dirlen, "/../lib");
 608   if (check_for_scripts_dir (dir))
 609     return;
 610
 611   /* Well, we tried.  */
 612   free (dir);
 613 }
 614
 615 void
 616 add_ysym (name)
 617      const char *name;
 618 {
 619   if (link_info.notice_hash == (struct bfd_hash_table *) NULL)
 620     {
 621       link_info.notice_hash = ((struct bfd_hash_table *)
 622                                xmalloc (sizeof (struct bfd_hash_table)));
 623       if (! bfd_hash_table_init_n (link_info.notice_hash,
 624                                    bfd_hash_newfunc,
 625                                    61))
 626         einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
 627     }
 628
 629   if (bfd_hash_lookup (link_info.notice_hash, name, true, true)
 630       == (struct bfd_hash_entry *) NULL)
 631     einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
 632 }
 633
 634 /* Record a symbol to be wrapped, from the --wrap option.  */
 635
 636 void
 637 add_wrap (name)
 638      const char *name;
 639 {
 640   if (link_info.wrap_hash == NULL)
 641     {
 642       link_info.wrap_hash = ((struct bfd_hash_table *)
 643                              xmalloc (sizeof (struct bfd_hash_table)));
 644       if (! bfd_hash_table_init_n (link_info.wrap_hash,
 645                                    bfd_hash_newfunc,
 646                                    61))
 647         einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
 648     }
 649   if (bfd_hash_lookup (link_info.wrap_hash, name, true, true) == NULL)
 650     einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
 651 }
 652
 653 /* Handle the -retain-symbols-file option.  */
 654
 655 void
 656 add_keepsyms_file (filename)
 657      const char *filename;
 658 {
 659   FILE *file;
 660   char *buf;
 661   size_t bufsize;
 662   int c;
 663
 664   if (link_info.strip == strip_some)
 665     einfo (_("%X%P: error: duplicate retain-symbols-file\n"));
 666
 667   file = fopen (filename, "r");
 668   if (file == (FILE *) NULL)
 669     {
 670       bfd_set_error (bfd_error_system_call);
 671       einfo ("%X%P: %s: %E\n", filename);
 672       return;
 673     }
 674
 675   link_info.keep_hash = ((struct bfd_hash_table *)
 676                          xmalloc (sizeof (struct bfd_hash_table)));
 677   if (! bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc))
 678     einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
 679
 680   bufsize = 100;
 681   buf = (char *) xmalloc (bufsize);
 682
 683   c = getc (file);
 684   while (c != EOF)
 685     {
 686       while (isspace (c))
 687         c = getc (file);
 688
 689       if (c != EOF)
 690         {
 691           size_t len = 0;
 692
 693           while (! isspace (c) && c != EOF)
 694             {
 695               buf[len] = c;
 696               ++len;
 697               if (len >= bufsize)
 698                 {
 699                   bufsize *= 2;
 700                   buf = xrealloc (buf, bufsize);
 701                 }
 702               c = getc (file);
 703             }
 704
 705           buf[len] = '\0';
 706
 707           if (bfd_hash_lookup (link_info.keep_hash, buf, true, true)
 708               == (struct bfd_hash_entry *) NULL)
 709             einfo (_("%P%F: bfd_hash_lookup for insertion failed: %E\n"));
 710         }
 711     }
 712
 713   if (link_info.strip != strip_none)
 714     einfo (_("%P: `-retain-symbols-file' overrides `-s' and `-S'\n"));
 715
 716   link_info.strip = strip_some;
 717 }
 718 \f
 719 /* Callbacks from the BFD linker routines.  */
 720
 721 /* This is called when BFD has decided to include an archive member in
 722    a link.  */
 723
 724 static boolean
 725 add_archive_element (info, abfd, name)
 726      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 727      bfd *abfd;
 728      const char *name;
 729 {
 730   lang_input_statement_type *input;
 731
 732   input = ((lang_input_statement_type *)
 733            xmalloc (sizeof (lang_input_statement_type)));
 734   input->filename = abfd->filename;
 735   input->local_sym_name = abfd->filename;
 736   input->the_bfd = abfd;
 737   input->asymbols = NULL;
 738   input->next = NULL;
 739   input->just_syms_flag = false;
 740   input->loaded = false;
 741   input->search_dirs_flag = false;
 742
 743   /* FIXME: The following fields are not set: header.next,
 744      header.type, closed, passive_position, symbol_count,
 745      next_real_file, is_archive, target, real.  This bit of code is
 746      from the old decode_library_subfile function.  I don't know
 747      whether any of those fields matters.  */
 748
 749   ldlang_add_file (input);
 750
 751   if (config.map_file != (FILE *) NULL)
 752     {
 753       static boolean header_printed;
 754       struct bfd_link_hash_entry *h;
 755       bfd *from;
 756       int len;
 757
 758       h = bfd_link_hash_lookup (link_info.hash, name, false, false, true);
 759
 760       if (h == NULL)
 761         from = NULL;
 762       else
 763         {
 764           switch (h->type)
 765             {
 766             default:
 767               from = NULL;
 768               break;
 769
 770             case bfd_link_hash_defined:
 771             case bfd_link_hash_defweak:
 772               from = h->u.def.section->owner;
 773               break;
 774
 775             case bfd_link_hash_undefined:
 776             case bfd_link_hash_undefweak:
 777               from = h->u.undef.abfd;
 778               break;
 779
 780             case bfd_link_hash_common:
 781               from = h->u.c.p->section->owner;
 782               break;
 783             }
 784         }
 785
 786       if (! header_printed)
 787         {
 788           char buf[100];
 789
 790           sprintf (buf, "%-29s %s\n\n", _("Archive member included"),
 791                    _("because of file (symbol)"));
 792           minfo ("%s", buf);
 793           header_printed = true;
 794         }
 795
 796       if (bfd_my_archive (abfd) == NULL)
 797         {
 798           minfo ("%s", bfd_get_filename (abfd));
 799           len = strlen (bfd_get_filename (abfd));
 800         }
 801       else
 802         {
 803           minfo ("%s(%s)", bfd_get_filename (bfd_my_archive (abfd)),
 804                  bfd_get_filename (abfd));
 805           len = (strlen (bfd_get_filename (bfd_my_archive (abfd)))
 806                  + strlen (bfd_get_filename (abfd))
 807                  + 2);
 808         }
 809
 810       if (len >= 29)
 811         {
 812           print_nl ();
 813           len = 0;
 814         }
 815       while (len < 30)
 816         {
 817           print_space ();
 818           ++len;
 819         }
 820
 821       if (from != NULL)
 822         minfo ("%B ", from);
 823       if (h != NULL)
 824         minfo ("(%T)\n", h->root.string);
 825       else
 826         minfo ("(%s)\n", name);
 827     }
 828
 829   if (trace_files || trace_file_tries)
 830     info_msg ("%I\n", input);
 831
 832   return true;
 833 }
 834
 835 /* This is called when BFD has discovered a symbol which is defined
 836    multiple times.  */
 837
 838 static boolean
 839 multiple_definition (info, name, obfd, osec, oval, nbfd, nsec, nval)
 840      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 841      const char *name;
 842      bfd *obfd;
 843      asection *osec;
 844      bfd_vma oval;
 845      bfd *nbfd;
 846      asection *nsec;
 847      bfd_vma nval;
 848 {
 849   /* If either section has the output_section field set to
 850      bfd_abs_section_ptr, it means that the section is being
 851      discarded, and this is not really a multiple definition at all.
 852      FIXME: It would be cleaner to somehow ignore symbols defined in
 853      sections which are being discarded.  */
 854   if ((osec->output_section != NULL
 855        && ! bfd_is_abs_section (osec)
 856        && bfd_is_abs_section (osec->output_section))
 857       || (nsec->output_section != NULL
 858           && ! bfd_is_abs_section (nsec)
 859           && bfd_is_abs_section (nsec->output_section)))
 860     return true;
 861
 862   einfo (_("%X%C: multiple definition of `%T'\n"),
 863          nbfd, nsec, nval, name);
 864   if (obfd != (bfd *) NULL)
 865     einfo (_("%D: first defined here\n"), obfd, osec, oval);
 866
 867   if (command_line.relax)
 868     {
 869       einfo (_("%P: Disabling relaxation: it will not work with multiple definitions\n"));
 870       command_line.relax = 0;
 871     }
 872
 873   return true;
 874 }
 875
 876 /* This is called when there is a definition of a common symbol, or
 877    when a common symbol is found for a symbol that is already defined,
 878    or when two common symbols are found.  We only do something if
 879    -warn-common was used.  */
 880
 881 static boolean
 882 multiple_common (info, name, obfd, otype, osize, nbfd, ntype, nsize)
 883      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 884      const char *name;
 885      bfd *obfd;
 886      enum bfd_link_hash_type otype;
 887      bfd_vma osize;
 888      bfd *nbfd;
 889      enum bfd_link_hash_type ntype;
 890      bfd_vma nsize;
 891 {
 892   if (! config.warn_common)
 893     return true;
 894
 895   if (ntype == bfd_link_hash_defined
 896       || ntype == bfd_link_hash_defweak
 897       || ntype == bfd_link_hash_indirect)
 898     {
 899       ASSERT (otype == bfd_link_hash_common);
 900       einfo (_("%B: warning: definition of `%T' overriding common\n"),
 901              nbfd, name);
 902       if (obfd != NULL)
 903         einfo (_("%B: warning: common is here\n"), obfd);
 904     }
 905   else if (otype == bfd_link_hash_defined
 906            || otype == bfd_link_hash_defweak
 907            || otype == bfd_link_hash_indirect)
 908     {
 909       ASSERT (ntype == bfd_link_hash_common);
 910       einfo (_("%B: warning: common of `%T' overridden by definition\n"),
 911              nbfd, name);
 912       if (obfd != NULL)
 913         einfo (_("%B: warning: defined here\n"), obfd);
 914     }
 915   else
 916     {
 917       ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
 918       if (osize > nsize)
 919         {
 920           einfo (_("%B: warning: common of `%T' overridden by larger common\n"),
 921                  nbfd, name);
 922           if (obfd != NULL)
 923             einfo (_("%B: warning: larger common is here\n"), obfd);
 924         }
 925       else if (nsize > osize)
 926         {
 927           einfo (_("%B: warning: common of `%T' overriding smaller common\n"),
 928                  nbfd, name);
 929           if (obfd != NULL)
 930             einfo (_("%B: warning: smaller common is here\n"), obfd);
 931         }
 932       else
 933         {
 934           einfo (_("%B: warning: multiple common of `%T'\n"), nbfd, name);
 935           if (obfd != NULL)
 936             einfo (_("%B: warning: previous common is here\n"), obfd);
 937         }
 938     }
 939
 940   return true;
 941 }
 942
 943 /* This is called when BFD has discovered a set element.  H is the
 944    entry in the linker hash table for the set.  SECTION and VALUE
 945    represent a value which should be added to the set.  */
 946
 947 static boolean
 948 add_to_set (info, h, reloc, abfd, section, value)
 949      struct bfd_link_info *info ATTRIBUTE_UNUSED;
 950      struct bfd_link_hash_entry *h;
 951      bfd_reloc_code_real_type reloc;
 952      bfd *abfd;
 953      asection *section;
 954      bfd_vma value;
 955 {
 956   if (config.warn_constructors)
 957     einfo (_("%P: warning: global constructor %s used\n"),
 958            h->root.string);
 959
 960   if (! config.build_constructors)
 961     return true;
 962
 963   ldctor_add_set_entry (h, reloc, (const char *) NULL, section, value);
 964
 965   if (h->type == bfd_link_hash_new)
 966     {
 967       h->type = bfd_link_hash_undefined;
 968       h->u.undef.abfd = abfd;
 969       /* We don't call bfd_link_add_undef to add this to the list of
 970          undefined symbols because we are going to define it
 971          ourselves.  */
 972     }
 973
 974   return true;
 975 }
 976
 977 /* This is called when BFD has discovered a constructor.  This is only
 978    called for some object file formats--those which do not handle
 979    constructors in some more clever fashion.  This is similar to
 980    adding an element to a set, but less general.  */
 981
 982 static boolean
 983 constructor_callback (info, constructor, name, abfd, section, value)
 984      struct bfd_link_info *info;
 985      boolean constructor;
 986      const char *name;
 987      bfd *abfd;
 988      asection *section;
 989      bfd_vma value;
 990 {
 991   char *s;
 992   struct bfd_link_hash_entry *h;
 993   char set_name[1 + sizeof "__CTOR_LIST__"];
 994
 995   if (config.warn_constructors)
 996     einfo (_("%P: warning: global constructor %s used\n"), name);
 997
 998   if (! config.build_constructors)
 999     return true;
1000
1001   /* Ensure that BFD_RELOC_CTOR exists now, so that we can give a
1002      useful error message.  */
1003   if (bfd_reloc_type_lookup (output_bfd, BFD_RELOC_CTOR) == NULL
1004       && (link_info.relocateable
1005           || bfd_reloc_type_lookup (abfd, BFD_RELOC_CTOR) == NULL))
1006     einfo (_("%P%F: BFD backend error: BFD_RELOC_CTOR unsupported\n"));
1007
1008   s = set_name;
1009   if (bfd_get_symbol_leading_char (abfd) != '\0')
1010     *s++ = bfd_get_symbol_leading_char (abfd);
1011   if (constructor)
1012     strcpy (s, "__CTOR_LIST__");
1013   else
1014     strcpy (s, "__DTOR_LIST__");
1015
1016   h = bfd_link_hash_lookup (info->hash, set_name, true, true, true);
1017   if (h == (struct bfd_link_hash_entry *) NULL)
1018     einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
1019   if (h->type == bfd_link_hash_new)
1020     {
1021       h->type = bfd_link_hash_undefined;
1022       h->u.undef.abfd = abfd;
1023       /* We don't call bfd_link_add_undef to add this to the list of
1024          undefined symbols because we are going to define it
1025          ourselves.  */
1026     }
1027
1028   ldctor_add_set_entry (h, BFD_RELOC_CTOR, name, section, value);
1029   return true;
1030 }
1031
1032 /* A structure used by warning_callback to pass information through
1033    bfd_map_over_sections.  */
1034
1035 struct warning_callback_info {
1036   boolean found;
1037   const char *warning;
1038   const char *symbol;
1039   asymbol **asymbols;
1040 };
1041
1042 /* This is called when there is a reference to a warning symbol.  */
1043
1044 static boolean
1045 warning_callback (info, warning, symbol, abfd, section, address)
1046      struct bfd_link_info *info ATTRIBUTE_UNUSED;
1047      const char *warning;
1048      const char *symbol;
1049      bfd *abfd;
1050      asection *section;
1051      bfd_vma address;
1052 {
1053   /* This is a hack to support warn_multiple_gp.  FIXME: This should
1054      have a cleaner interface, but what?  */
1055   if (! config.warn_multiple_gp
1056       && strcmp (warning, "using multiple gp values") == 0)
1057     return true;
1058
1059   if (section != NULL)
1060     einfo ("%C: %s\n", abfd, section, address, warning);
1061   else if (abfd == NULL)
1062     einfo ("%P: %s\n", warning);
1063   else if (symbol == NULL)
1064     einfo ("%B: %s\n", abfd, warning);
1065   else
1066     {
1067       lang_input_statement_type *entry;
1068       asymbol **asymbols;
1069       struct warning_callback_info info;
1070
1071       /* Look through the relocs to see if we can find a plausible
1072          address.  */
1073
1074       entry = (lang_input_statement_type *) abfd->usrdata;
1075       if (entry != NULL && entry->asymbols != NULL)
1076         asymbols = entry->asymbols;
1077       else
1078         {
1079           long symsize;
1080           long symbol_count;
1081
1082           symsize = bfd_get_symtab_upper_bound (abfd);
1083           if (symsize < 0)
1084             einfo (_("%B%F: could not read symbols: %E\n"), abfd);
1085           asymbols = (asymbol **) xmalloc (symsize);
1086           symbol_count = bfd_canonicalize_symtab (abfd, asymbols);
1087           if (symbol_count < 0)
1088             einfo (_("%B%F: could not read symbols: %E\n"), abfd);
1089           if (entry != NULL)
1090             {
1091               entry->asymbols = asymbols;
1092               entry->symbol_count = symbol_count;
1093             }
1094         }
1095
1096       info.found = false;
1097       info.warning = warning;
1098       info.symbol = symbol;
1099       info.asymbols = asymbols;
1100       bfd_map_over_sections (abfd, warning_find_reloc, (PTR) &info);
1101
1102       if (! info.found)
1103         einfo ("%B: %s\n", abfd, warning);
1104
1105       if (entry == NULL)
1106         free (asymbols);
1107     }
1108
1109   return true;
1110 }
1111
1112 /* This is called by warning_callback for each section.  It checks the
1113    relocs of the section to see if it can find a reference to the
1114    symbol which triggered the warning.  If it can, it uses the reloc
1115    to give an error message with a file and line number.  */
1116
1117 static void
1118 warning_find_reloc (abfd, sec, iarg)
1119      bfd *abfd;
1120      asection *sec;
1121      PTR iarg;
1122 {
1123   struct warning_callback_info *info = (struct warning_callback_info *) iarg;
1124   long relsize;
1125   arelent **relpp;
1126   long relcount;
1127   arelent **p, **pend;
1128
1129   if (info->found)
1130     return;
1131
1132   relsize = bfd_get_reloc_upper_bound (abfd, sec);
1133   if (relsize < 0)
1134     einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1135   if (relsize == 0)
1136     return;
1137
1138   relpp = (arelent **) xmalloc (relsize);
1139   relcount = bfd_canonicalize_reloc (abfd, sec, relpp, info->asymbols);
1140   if (relcount < 0)
1141     einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1142
1143   p = relpp;
1144   pend = p + relcount;
1145   for (; p < pend && *p != NULL; p++)
1146     {
1147       arelent *q = *p;
1148
1149       if (q->sym_ptr_ptr != NULL
1150           && *q->sym_ptr_ptr != NULL
1151           && strcmp (bfd_asymbol_name (*q->sym_ptr_ptr), info->symbol) == 0)
1152         {
1153           /* We found a reloc for the symbol we are looking for.  */
1154           einfo ("%C: %s\n", abfd, sec, q->address, info->warning);
1155           info->found = true;
1156           break;
1157         }
1158     }
1159
1160   free (relpp);
1161 }
1162
1163 /* This is called when an undefined symbol is found.  */
1164
1165 static boolean
1166 undefined_symbol (info, name, abfd, section, address, fatal)
1167      struct bfd_link_info *info ATTRIBUTE_UNUSED;
1168      const char *name;
1169      bfd *abfd;
1170      asection *section;
1171      bfd_vma address;
1172      boolean fatal ATTRIBUTE_UNUSED;
1173 {
1174   static char *error_name;
1175   static unsigned int error_count;
1176
1177 #define MAX_ERRORS_IN_A_ROW 5
1178
1179   if (config.warn_once)
1180     {
1181       static struct bfd_hash_table *hash;
1182
1183       /* Only warn once about a particular undefined symbol.  */
1184
1185       if (hash == NULL)
1186         {
1187           hash = ((struct bfd_hash_table *)
1188                   xmalloc (sizeof (struct bfd_hash_table)));
1189           if (! bfd_hash_table_init (hash, bfd_hash_newfunc))
1190             einfo (_("%F%P: bfd_hash_table_init failed: %E\n"));
1191         }
1192
1193       if (bfd_hash_lookup (hash, name, false, false) != NULL)
1194         return true;
1195
1196       if (bfd_hash_lookup (hash, name, true, true) == NULL)
1197         einfo (_("%F%P: bfd_hash_lookup failed: %E\n"));
1198     }
1199
1200   /* We never print more than a reasonable number of errors in a row
1201      for a single symbol.  */
1202   if (error_name != (char *) NULL
1203       && strcmp (name, error_name) == 0)
1204     ++error_count;
1205   else
1206     {
1207       error_count = 0;
1208       if (error_name != (char *) NULL)
1209         free (error_name);
1210       error_name = xstrdup (name);
1211     }
1212
1213   if (section != NULL)
1214     {
1215       if (error_count < MAX_ERRORS_IN_A_ROW)
1216         {
1217           einfo (_("%C: undefined reference to `%T'\n"),
1218                  abfd, section, address, name);
1219           if (fatal)
1220             einfo ("%X");
1221         }
1222       else if (error_count == MAX_ERRORS_IN_A_ROW)
1223         einfo (_("%D: more undefined references to `%T' follow\n"),
1224                abfd, section, address, name);
1225     }
1226   else
1227     {
1228       if (error_count < MAX_ERRORS_IN_A_ROW)
1229         {
1230           einfo (_("%B: undefined reference to `%T'\n"),
1231                  abfd, name);
1232           if (fatal)
1233             einfo ("%X");
1234         }
1235       else if (error_count == MAX_ERRORS_IN_A_ROW)
1236         einfo (_("%B: more undefined references to `%T' follow\n"),
1237                abfd, name);
1238     }
1239
1240   return true;
1241 }
1242
1243 /* This is called when a reloc overflows.  */
1244
1245 static boolean
1246 reloc_overflow (info, name, reloc_name, addend, abfd, section, address)
1247      struct bfd_link_info *info ATTRIBUTE_UNUSED;
1248      const char *name;
1249      const char *reloc_name;
1250      bfd_vma addend;
1251      bfd *abfd;
1252      asection *section;
1253      bfd_vma address;
1254 {
1255   if (abfd == (bfd *) NULL)
1256     einfo (_("%P%X: generated"));
1257   else
1258     einfo ("%X%C:", abfd, section, address);
1259   einfo (_(" relocation truncated to fit: %s %T"), reloc_name, name);
1260   if (addend != 0)
1261     einfo ("+%v", addend);
1262   einfo ("\n");
1263   return true;
1264 }
1265
1266 /* This is called when a dangerous relocation is made.  */
1267
1268 static boolean
1269 reloc_dangerous (info, message, abfd, section, address)
1270      struct bfd_link_info *info ATTRIBUTE_UNUSED;
1271      const char *message;
1272      bfd *abfd;
1273      asection *section;
1274      bfd_vma address;
1275 {
1276   if (abfd == (bfd *) NULL)
1277     einfo (_("%P%X: generated"));
1278   else
1279     einfo ("%X%C:", abfd, section, address);
1280   einfo (_("dangerous relocation: %s\n"), message);
1281   return true;
1282 }
1283
1284 /* This is called when a reloc is being generated attached to a symbol
1285    that is not being output.  */
1286
1287 static boolean
1288 unattached_reloc (info, name, abfd, section, address)
1289      struct bfd_link_info *info ATTRIBUTE_UNUSED;
1290      const char *name;
1291      bfd *abfd;
1292      asection *section;
1293      bfd_vma address;
1294 {
1295   if (abfd == (bfd *) NULL)
1296     einfo (_("%P%X: generated"));
1297   else
1298     einfo ("%X%C:", abfd, section, address);
1299   einfo (_(" reloc refers to symbol `%T' which is not being output\n"), name);
1300   return true;
1301 }
1302
1303 /* This is called if link_info.notice_all is set, or when a symbol in
1304    link_info.notice_hash is found.  Symbols are put in notice_hash
1305    using the -y option.  */
1306
1307 static boolean
1308 notice (info, name, abfd, section, value)
1309      struct bfd_link_info *info;
1310      const char *name;
1311      bfd *abfd;
1312      asection *section;
1313      bfd_vma value;
1314 {
1315   if (! info->notice_all
1316       || (info->notice_hash != NULL
1317           && bfd_hash_lookup (info->notice_hash, name, false, false) != NULL))
1318     {
1319       if (bfd_is_und_section (section))
1320         einfo ("%B: reference to %s\n", abfd, name);
1321       else
1322         einfo ("%B: definition of %s\n", abfd, name);
1323     }
1324
1325   if (command_line.cref || nocrossref_list != NULL)
1326     add_cref (name, abfd, section, value);
1327
1328   return true;
1329 }