ld/ldmain.c

   1 /* Main program of GNU linker.
   2    Copyright (C) 1991, 92, 93, 94 Free Software Foundation, Inc.
   3    Written by Steve Chamberlain steve@cygnus.com
   4
   5 This file is part of GLD, the Gnu Linker.
   6
   7 GLD is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GLD is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GLD; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21
  22 #include "bfd.h"
  23 #include "sysdep.h"
  24 #include <stdio.h>
  25 #include "libiberty.h"
  26 #include "progress.h"
  27 #include "bfdlink.h"
  28
  29 #include "config.h"
  30 #include "ld.h"
  31 #include "ldmain.h"
  32 #include "ldmisc.h"
  33 #include "ldwrite.h"
  34 #include "ldgram.h"
  35 #include "ldexp.h"
  36 #include "ldlang.h"
  37 #include "ldemul.h"
  38 #include "ldlex.h"
  39 #include "ldfile.h"
  40 #include "ldctor.h"
  41
  42 /* Somewhere above, sys/stat.h got included . . . . */
  43 #if !defined(S_ISDIR) && defined(S_IFDIR)
  44 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
  45 #endif
  46
  47 #include <string.h>
  48
  49 static char *get_emulation PARAMS ((int, char **));
  50 static void set_scripts_dir PARAMS ((void));
  51
  52 /* EXPORTS */
  53
  54 char *default_target;
  55 const char *output_filename = "a.out";
  56
  57 /* Name this program was invoked by.  */
  58 char *program_name;
  59
  60 /* The file that we're creating */
  61 bfd *output_bfd = 0;
  62
  63 /* Set by -G argument, for MIPS ECOFF target.  */
  64 int g_switch_value = 8;
  65
  66 /* Nonzero means print names of input files as processed.  */
  67 boolean trace_files;
  68
  69 /* Nonzero means same, but note open failures, too.  */
  70 boolean trace_file_tries;
  71
  72 /* Nonzero means version number was printed, so exit successfully
  73    instead of complaining if no input files are given.  */
  74 boolean version_printed;
  75
  76 /* Nonzero means link in every member of an archive.  */
  77 boolean whole_archive;
  78
  79 args_type command_line;
  80
  81 ld_config_type config;
  82
  83 static boolean check_for_scripts_dir PARAMS ((char *dir));
  84 static boolean add_archive_element PARAMS ((struct bfd_link_info *, bfd *,
  85                                             const char *));
  86 static boolean multiple_definition PARAMS ((struct bfd_link_info *,
  87                                             const char *,
  88                                             bfd *, asection *, bfd_vma,
  89                                             bfd *, asection *, bfd_vma));
  90 static boolean multiple_common PARAMS ((struct bfd_link_info *,
  91                                         const char *, bfd *,
  92                                         enum bfd_link_hash_type, bfd_vma,
  93                                         bfd *, enum bfd_link_hash_type,
  94                                         bfd_vma));
  95 static boolean add_to_set PARAMS ((struct bfd_link_info *,
  96                                    struct bfd_link_hash_entry *,
  97                                    bfd_reloc_code_real_type,
  98                                    bfd *, asection *, bfd_vma));
  99 static boolean constructor_callback PARAMS ((struct bfd_link_info *,
 100                                              boolean constructor,
 101                                              const char *name,
 102                                              bfd *, asection *, bfd_vma));
 103 static boolean warning_callback PARAMS ((struct bfd_link_info *,
 104                                          const char *));
 105 static boolean undefined_symbol PARAMS ((struct bfd_link_info *,
 106                                          const char *, bfd *,
 107                                          asection *, bfd_vma));
 108 static boolean reloc_overflow PARAMS ((struct bfd_link_info *, const char *,
 109                                        const char *, bfd_vma,
 110                                        bfd *, asection *, bfd_vma));
 111 static boolean reloc_dangerous PARAMS ((struct bfd_link_info *, const char *,
 112                                         bfd *, asection *, bfd_vma));
 113 static boolean unattached_reloc PARAMS ((struct bfd_link_info *,
 114                                          const char *, bfd *, asection *,
 115                                          bfd_vma));
 116 static boolean notice_ysym PARAMS ((struct bfd_link_info *, const char *,
 117                                     bfd *, asection *, bfd_vma));
 118
 119 static struct bfd_link_callbacks link_callbacks =
 120 {
 121   add_archive_element,
 122   multiple_definition,
 123   multiple_common,
 124   add_to_set,
 125   constructor_callback,
 126   warning_callback,
 127   undefined_symbol,
 128   reloc_overflow,
 129   reloc_dangerous,
 130   unattached_reloc,
 131   notice_ysym
 132 };
 133
 134 struct bfd_link_info link_info;
 135 \f
 136 static void
 137 remove_output ()
 138 {
 139   if (output_filename)
 140     {
 141       if (output_bfd && output_bfd->iostream)
 142         fclose((FILE *)(output_bfd->iostream));
 143       if (delete_output_file_on_failure)
 144         unlink (output_filename);
 145     }
 146 }
 147
 148 int
 149 main (argc, argv)
 150      int argc;
 151      char **argv;
 152 {
 153   char *emulation;
 154   long start_time = get_run_time ();
 155
 156   program_name = argv[0];
 157   xmalloc_set_program_name (program_name);
 158
 159   START_PROGRESS (program_name, 0);
 160
 161   bfd_init ();
 162
 163   xatexit (remove_output);
 164
 165   /* Initialize the data about options.  */
 166   trace_files = trace_file_tries = version_printed = false;
 167   whole_archive = false;
 168   config.traditional_format = false;
 169   config.build_constructors = true;
 170   config.dynamic_link = false;
 171   command_line.force_common_definition = false;
 172   command_line.interpreter = NULL;
 173   command_line.rpath = NULL;
 174
 175   link_info.callbacks = &link_callbacks;
 176   link_info.relocateable = false;
 177   link_info.shared = false;
 178   link_info.strip = strip_none;
 179   link_info.discard = discard_none;
 180   link_info.lprefix_len = 1;
 181   link_info.lprefix = "L";
 182   link_info.keep_memory = true;
 183   link_info.input_bfds = NULL;
 184   link_info.create_object_symbols_section = NULL;
 185   link_info.hash = NULL;
 186   link_info.keep_hash = NULL;
 187   link_info.notice_hash = NULL;
 188
 189   ldfile_add_arch ("");
 190
 191   config.make_executable = true;
 192   force_make_executable = false;
 193   config.magic_demand_paged = true;
 194   config.text_read_only = true;
 195   config.make_executable = true;
 196
 197   emulation = get_emulation (argc, argv);
 198   ldemul_choose_mode (emulation);
 199   default_target = ldemul_choose_target ();
 200   lang_init ();
 201   ldemul_before_parse ();
 202   lang_has_input_file = false;
 203   parse_args (argc, argv);
 204
 205   if (link_info.relocateable)
 206     {
 207       if (command_line.relax)
 208         einfo ("%P%F: -relax and -r may not be used together\n");
 209       if (config.dynamic_link)
 210         einfo ("%P%F: -r and -call_shared may not be used together\n");
 211       if (link_info.shared)
 212         einfo ("%P%F: -r and -shared may not be used together\n");
 213     }
 214
 215   /* Treat ld -r -s as ld -r -S -x (i.e., strip all local symbols).  I
 216      don't see how else this can be handled, since in this case we
 217      must preserve all externally visible symbols.  */
 218   if (link_info.relocateable && link_info.strip == strip_all)
 219     {
 220       link_info.strip = strip_debugger;
 221       if (link_info.discard == discard_none)
 222         link_info.discard = discard_all;
 223     }
 224
 225   /* This essentially adds another -L directory so this must be done after
 226      the -L's in argv have been processed.  */
 227   set_scripts_dir ();
 228
 229   if (had_script == false)
 230     {
 231       /* Read the emulation's appropriate default script.  */
 232       int isfile;
 233       char *s = ldemul_get_script (&isfile);
 234
 235       if (isfile)
 236         ldfile_open_command_file (s);
 237       else
 238         {
 239           if (trace_file_tries)
 240             {
 241               info_msg ("using internal linker script:\n");
 242               info_msg ("==================================================\n");
 243               info_msg (s);
 244               info_msg ("\n==================================================\n");
 245             }
 246           lex_redirect (s);
 247         }
 248       parser_input = input_script;
 249       yyparse ();
 250     }
 251
 252   lang_final ();
 253
 254   if (lang_has_input_file == false)
 255     {
 256       if (version_printed)
 257         xexit (0);
 258       einfo ("%P%F: no input files\n");
 259     }
 260
 261   if (trace_files)
 262     {
 263       info_msg ("%P: mode %s\n", emulation);
 264     }
 265
 266   ldemul_after_parse ();
 267
 268
 269   if (config.map_filename)
 270     {
 271       if (strcmp (config.map_filename, "-") == 0)
 272         {
 273           config.map_file = stdout;
 274         }
 275       else
 276         {
 277           config.map_file = fopen (config.map_filename, FOPEN_WT);
 278           if (config.map_file == (FILE *) NULL)
 279             {
 280               einfo ("%P%F: cannot open map file %s: %E\n",
 281                      config.map_filename);
 282             }
 283         }
 284     }
 285
 286
 287   lang_process ();
 288
 289   /* Print error messages for any missing symbols, for any warning
 290      symbols, and possibly multiple definitions */
 291
 292
 293   if (config.text_read_only)
 294     {
 295       /* Look for a text section and mark the readonly attribute in it */
 296       asection *found = bfd_get_section_by_name (output_bfd, ".text");
 297
 298       if (found != (asection *) NULL)
 299         {
 300           found->flags |= SEC_READONLY;
 301         }
 302     }
 303
 304   if (link_info.relocateable)
 305     output_bfd->flags &= ~EXEC_P;
 306   else
 307     output_bfd->flags |= EXEC_P;
 308
 309   ldwrite ();
 310
 311   /* Even if we're producing relocateable output, some non-fatal errors should
 312      be reported in the exit status.  (What non-fatal errors, if any, do we
 313      want to ignore for relocateable output?)  */
 314
 315   if (config.make_executable == false && force_make_executable == false)
 316     {
 317       if (trace_files == true)
 318         {
 319           einfo ("%P: link errors found, deleting executable `%s'\n",
 320                  output_filename);
 321         }
 322
 323       if (output_bfd->iostream)
 324         fclose ((FILE *) (output_bfd->iostream));
 325
 326       unlink (output_filename);
 327       xexit (1);
 328     }
 329   else
 330     {
 331       if (! bfd_close (output_bfd))
 332         einfo ("%F%B: final close failed: %E\n", output_bfd);
 333     }
 334
 335   END_PROGRESS (program_name);
 336
 337   if (config.stats)
 338     {
 339       extern char **environ;
 340       char *lim = (char *) sbrk (0);
 341       long run_time = get_run_time () - start_time;
 342
 343       fprintf (stderr, "%s: total time in link: %ld.%06ld\n",
 344                program_name, run_time / 1000000, run_time % 1000000);
 345       fprintf (stderr, "%s: data size %ld\n", program_name,
 346                (long) (lim - (char *) &environ));
 347     }
 348
 349   /* Prevent remove_output from doing anything, after a successful link.  */
 350   output_filename = NULL;
 351
 352   xexit (0);
 353   return 0;
 354 }
 355
 356 /* We need to find any explicitly given emulation in order to initialize the
 357    state that's needed by the lex&yacc argument parser (parse_args).  */
 358
 359 static char *
 360 get_emulation (argc, argv)
 361      int argc;
 362      char **argv;
 363 {
 364   char *emulation;
 365   int i;
 366
 367   emulation = (char *) getenv (EMULATION_ENVIRON);
 368   if (emulation == NULL)
 369     emulation = DEFAULT_EMULATION;
 370
 371   for (i = 1; i < argc; i++)
 372     {
 373       if (!strncmp (argv[i], "-m", 2))
 374         {
 375           if (argv[i][2] == '\0')
 376             {
 377               /* -m EMUL */
 378               if (i < argc - 1)
 379                 {
 380                   emulation = argv[i + 1];
 381                   i++;
 382                 }
 383               else
 384                 {
 385                   einfo("%P%F: missing argument to -m\n");
 386                 }
 387             }
 388           else if (strcmp (argv[i], "-mips1") == 0
 389                    || strcmp (argv[i], "-mips2") == 0
 390                    || strcmp (argv[i], "-mips3") == 0)
 391             {
 392               /* FIXME: The arguments -mips1, -mips2 and -mips3 are
 393                  passed to the linker by some MIPS compilers.  They
 394                  generally tell the linker to use a slightly different
 395                  library path.  Perhaps someday these should be
 396                  implemented as emulations; until then, we just ignore
 397                  the arguments and hope that nobody ever creates
 398                  emulations named ips1, ips2 or ips3.  */
 399             }
 400           else if (strcmp (argv[i], "-m486") == 0)
 401             {
 402               /* FIXME: The argument -m486 is passed to the linker on
 403                  some Linux systems.  Hope that nobody creates an
 404                  emulation named 486.  */
 405             }
 406           else
 407             {
 408               /* -mEMUL */
 409               emulation = &argv[i][2];
 410             }
 411         }
 412     }
 413
 414   return emulation;
 415 }
 416
 417 /* If directory DIR contains an "ldscripts" subdirectory,
 418    add DIR to the library search path and return true,
 419    else return false.  */
 420
 421 static boolean
 422 check_for_scripts_dir (dir)
 423      char *dir;
 424 {
 425   size_t dirlen;
 426   char *buf;
 427   struct stat s;
 428   boolean res;
 429
 430   dirlen = strlen (dir);
 431   /* sizeof counts the terminating NUL.  */
 432   buf = (char *) xmalloc (dirlen + sizeof("/ldscripts"));
 433   sprintf (buf, "%s/ldscripts", dir);
 434
 435   res = stat (buf, &s) == 0 && S_ISDIR (s.st_mode);
 436   free (buf);
 437   if (res)
 438     ldfile_add_library_path (dir, false);
 439   return res;
 440 }
 441
 442 /* Set the default directory for finding script files.
 443    Libraries will be searched for here too, but that's ok.
 444    We look for the "ldscripts" directory in:
 445
 446    SCRIPTDIR (passed from Makefile)
 447    the dir where this program is (for using it from the build tree)
 448    the dir where this program is/../lib (for installing the tool suite elsewhere) */
 449
 450 static void
 451 set_scripts_dir ()
 452 {
 453   char *end, *dir;
 454   size_t dirlen;
 455
 456   if (check_for_scripts_dir (SCRIPTDIR))
 457     return;                     /* We've been installed normally.  */
 458
 459   /* Look for "ldscripts" in the dir where our binary is.  */
 460   end = strrchr (program_name, '/');
 461   if (end)
 462     {
 463       dirlen = end - program_name;
 464       /* Make a copy of program_name in dir.
 465          Leave room for later "/../lib".  */
 466       dir = (char *) xmalloc (dirlen + 8);
 467       strncpy (dir, program_name, dirlen);
 468       dir[dirlen] = '\0';
 469     }
 470   else
 471     {
 472       dirlen = 1;
 473       dir = (char *) xmalloc (dirlen + 8);
 474       strcpy (dir, ".");
 475     }
 476
 477   if (check_for_scripts_dir (dir))
 478     return;                     /* Don't free dir.  */
 479
 480   /* Look for "ldscripts" in <the dir where our binary is>/../lib.  */
 481   strcpy (dir + dirlen, "/../lib");
 482   if (check_for_scripts_dir (dir))
 483     return;
 484
 485   free (dir);                   /* Well, we tried.  */
 486 }
 487
 488 void
 489 add_ysym (name)
 490      const char *name;
 491 {
 492   if (link_info.notice_hash == (struct bfd_hash_table *) NULL)
 493     {
 494       link_info.notice_hash = ((struct bfd_hash_table *)
 495                                xmalloc (sizeof (struct bfd_hash_table)));
 496       if (! bfd_hash_table_init_n (link_info.notice_hash,
 497                                    bfd_hash_newfunc,
 498                                    61))
 499         einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 500     }
 501
 502   if (bfd_hash_lookup (link_info.notice_hash, name, true, true)
 503       == (struct bfd_hash_entry *) NULL)
 504     einfo ("%P%F: bfd_hash_lookup failed: %E\n");
 505 }
 506
 507 /* Handle the -retain-symbols-file option.  */
 508
 509 void
 510 add_keepsyms_file (filename)
 511      const char *filename;
 512 {
 513   FILE *file;
 514   char *buf;
 515   size_t bufsize;
 516   int c;
 517
 518   if (link_info.strip == strip_some)
 519     einfo ("%X%P: error: duplicate retain-symbols-file\n");
 520
 521   file = fopen (filename, "r");
 522   if (file == (FILE *) NULL)
 523     {
 524       bfd_set_error (bfd_error_system_call);
 525       einfo ("%X%P: %s: %E", filename);
 526       return;
 527     }
 528
 529   link_info.keep_hash = ((struct bfd_hash_table *)
 530                          xmalloc (sizeof (struct bfd_hash_table)));
 531   if (! bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc))
 532     einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 533
 534   bufsize = 100;
 535   buf = (char *) xmalloc (bufsize);
 536
 537   c = getc (file);
 538   while (c != EOF)
 539     {
 540       while (isspace (c))
 541         c = getc (file);
 542
 543       if (c != EOF)
 544         {
 545           size_t len = 0;
 546
 547           while (! isspace (c) && c != EOF)
 548             {
 549               buf[len] = c;
 550               ++len;
 551               if (len >= bufsize)
 552                 {
 553                   bufsize *= 2;
 554                   buf = xrealloc (buf, bufsize);
 555                 }
 556               c = getc (file);
 557             }
 558
 559           buf[len] = '\0';
 560
 561           if (bfd_hash_lookup (link_info.keep_hash, buf, true, true)
 562               == (struct bfd_hash_entry *) NULL)
 563             einfo ("%P%F: bfd_hash_lookup for insertion failed: %E");
 564         }
 565     }
 566
 567   if (link_info.strip != strip_none)
 568     einfo ("%P: `-retain-symbols-file' overrides `-s' and `-S'\n");
 569
 570   link_info.strip = strip_some;
 571 }
 572 \f
 573 /* Callbacks from the BFD linker routines.  */
 574
 575 /* This is called when BFD has decided to include an archive member in
 576    a link.  */
 577
 578 /*ARGSUSED*/
 579 static boolean
 580 add_archive_element (info, abfd, name)
 581      struct bfd_link_info *info;
 582      bfd *abfd;
 583      const char *name;
 584 {
 585   lang_input_statement_type *input;
 586
 587   input = ((lang_input_statement_type *)
 588            xmalloc ((bfd_size_type) sizeof (lang_input_statement_type)));
 589   input->filename = abfd->filename;
 590   input->local_sym_name = abfd->filename;
 591   input->the_bfd = abfd;
 592   input->asymbols = NULL;
 593   input->next = NULL;
 594   input->just_syms_flag = false;
 595   input->loaded = false;
 596   input->search_dirs_flag = false;
 597
 598   /* FIXME: The following fields are not set: header.next,
 599      header.type, closed, passive_position, symbol_count,
 600      next_real_file, is_archive, target, real, common_section,
 601      common_output_section, complained.  This bit of code is from the
 602      old decode_library_subfile function.  I don't know whether any of
 603      those fields matters.  */
 604
 605   ldlang_add_file (input);
 606
 607   if (config.map_file != (FILE *) NULL)
 608     minfo ("%s needed due to %T\n", abfd->filename, name);
 609
 610   if (trace_files || trace_file_tries)
 611     info_msg ("%I\n", input);
 612
 613   return true;
 614 }
 615
 616 /* This is called when BFD has discovered a symbol which is defined
 617    multiple times.  */
 618
 619 /*ARGSUSED*/
 620 static boolean
 621 multiple_definition (info, name, obfd, osec, oval, nbfd, nsec, nval)
 622      struct bfd_link_info *info;
 623      const char *name;
 624      bfd *obfd;
 625      asection *osec;
 626      bfd_vma oval;
 627      bfd *nbfd;
 628      asection *nsec;
 629      bfd_vma nval;
 630 {
 631   einfo ("%X%C: multiple definition of `%T'\n",
 632          nbfd, nsec, nval, name);
 633   if (obfd != (bfd *) NULL)
 634     einfo ("%D: first defined here\n", obfd, osec, oval);
 635   return true;
 636 }
 637
 638 /* This is called when there is a definition of a common symbol, or
 639    when a common symbol is found for a symbol that is already defined,
 640    or when two common symbols are found.  We only do something if
 641    -warn-common was used.  */
 642
 643 /*ARGSUSED*/
 644 static boolean
 645 multiple_common (info, name, obfd, otype, osize, nbfd, ntype, nsize)
 646      struct bfd_link_info *info;
 647      const char *name;
 648      bfd *obfd;
 649      enum bfd_link_hash_type otype;
 650      bfd_vma osize;
 651      bfd *nbfd;
 652      enum bfd_link_hash_type ntype;
 653      bfd_vma nsize;
 654 {
 655   if (! config.warn_common)
 656     return true;
 657
 658   if (ntype == bfd_link_hash_defined
 659       || ntype == bfd_link_hash_defweak
 660       || ntype == bfd_link_hash_indirect)
 661     {
 662       ASSERT (otype == bfd_link_hash_common);
 663       einfo ("%B: warning: definition of `%T' overriding common\n",
 664              nbfd, name);
 665       if (obfd != NULL)
 666         einfo ("%B: warning: common is here\n", obfd);
 667     }
 668   else if (otype == bfd_link_hash_defined
 669            || otype == bfd_link_hash_defweak
 670            || otype == bfd_link_hash_indirect)
 671     {
 672       ASSERT (ntype == bfd_link_hash_common);
 673       einfo ("%B: warning: common of `%T' overridden by definition\n",
 674              nbfd, name);
 675       if (obfd != NULL)
 676         einfo ("%B: warning: defined here\n", obfd);
 677     }
 678   else
 679     {
 680       ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
 681       if (osize > nsize)
 682         {
 683           einfo ("%B: warning: common of `%T' overridden by larger common\n",
 684                  nbfd, name);
 685           if (obfd != NULL)
 686             einfo ("%B: warning: larger common is here\n", obfd);
 687         }
 688       else if (nsize > osize)
 689         {
 690           einfo ("%B: warning: common of `%T' overriding smaller common\n",
 691                  nbfd, name);
 692           if (obfd != NULL)
 693             einfo ("%B: warning: smaller common is here\n", obfd);
 694         }
 695       else
 696         {
 697           einfo ("%B: warning: multiple common of `%T'\n", nbfd, name);
 698           if (obfd != NULL)
 699             einfo ("%B: warning: previous common is here\n", obfd);
 700         }
 701     }
 702
 703   return true;
 704 }
 705
 706 /* This is called when BFD has discovered a set element.  H is the
 707    entry in the linker hash table for the set.  SECTION and VALUE
 708    represent a value which should be added to the set.  */
 709
 710 /*ARGSUSED*/
 711 static boolean
 712 add_to_set (info, h, reloc, abfd, section, value)
 713      struct bfd_link_info *info;
 714      struct bfd_link_hash_entry *h;
 715      bfd_reloc_code_real_type reloc;
 716      bfd *abfd;
 717      asection *section;
 718      bfd_vma value;
 719 {
 720   if (! config.build_constructors)
 721     return true;
 722
 723   ldctor_add_set_entry (h, reloc, section, value);
 724
 725   if (h->type == bfd_link_hash_new)
 726     {
 727       h->type = bfd_link_hash_undefined;
 728       h->u.undef.abfd = abfd;
 729       /* We don't call bfd_link_add_undef to add this to the list of
 730          undefined symbols because we are going to define it
 731          ourselves.  */
 732     }
 733
 734   return true;
 735 }
 736
 737 /* This is called when BFD has discovered a constructor.  This is only
 738    called for some object file formats--those which do not handle
 739    constructors in some more clever fashion.  This is similar to
 740    adding an element to a set, but less general.  */
 741
 742 static boolean
 743 constructor_callback (info, constructor, name, abfd, section, value)
 744      struct bfd_link_info *info;
 745      boolean constructor;
 746      const char *name;
 747      bfd *abfd;
 748      asection *section;
 749      bfd_vma value;
 750 {
 751   char *set_name;
 752   char *s;
 753   struct bfd_link_hash_entry *h;
 754
 755   if (! config.build_constructors)
 756     return true;
 757
 758   /* Ensure that BFD_RELOC_CTOR exists now, so that we can give a
 759      useful error message.  */
 760   if (bfd_reloc_type_lookup (output_bfd, BFD_RELOC_CTOR) == NULL)
 761     einfo ("%P%F: BFD backend error: BFD_RELOC_CTOR unsupported");
 762
 763   set_name = (char *) alloca (1 + sizeof "__CTOR_LIST__");
 764   s = set_name;
 765   if (bfd_get_symbol_leading_char (abfd) != '\0')
 766     *s++ = bfd_get_symbol_leading_char (abfd);
 767   if (constructor)
 768     strcpy (s, "__CTOR_LIST__");
 769   else
 770     strcpy (s, "__DTOR_LIST__");
 771
 772   if (config.map_file != (FILE *) NULL)
 773     fprintf (config.map_file,
 774              "Adding %s to constructor/destructor set %s\n", name, set_name);
 775
 776   h = bfd_link_hash_lookup (info->hash, set_name, true, true, true);
 777   if (h == (struct bfd_link_hash_entry *) NULL)
 778     einfo ("%P%F: bfd_link_hash_lookup failed: %E");
 779   if (h->type == bfd_link_hash_new)
 780     {
 781       h->type = bfd_link_hash_undefined;
 782       h->u.undef.abfd = abfd;
 783       /* We don't call bfd_link_add_undef to add this to the list of
 784          undefined symbols because we are going to define it
 785          ourselves.  */
 786     }
 787
 788   ldctor_add_set_entry (h, BFD_RELOC_CTOR, section, value);
 789   return true;
 790 }
 791
 792 /* This is called when there is a reference to a warning symbol.  */
 793
 794 /*ARGSUSED*/
 795 static boolean
 796 warning_callback (info, warning)
 797      struct bfd_link_info *info;
 798      const char *warning;
 799 {
 800   einfo ("%P: %s\n", warning);
 801   return true;
 802 }
 803
 804 /* This is called when an undefined symbol is found.  */
 805
 806 /*ARGSUSED*/
 807 static boolean
 808 undefined_symbol (info, name, abfd, section, address)
 809      struct bfd_link_info *info;
 810      const char *name;
 811      bfd *abfd;
 812      asection *section;
 813      bfd_vma address;
 814 {
 815   static char *error_name;
 816   static unsigned int error_count;
 817
 818 #define MAX_ERRORS_IN_A_ROW 5
 819
 820   if (config.warn_once)
 821     {
 822       static struct bfd_hash_table *hash;
 823
 824       /* Only warn once about a particular undefined symbol.  */
 825
 826       if (hash == NULL)
 827         {
 828           hash = ((struct bfd_hash_table *)
 829                   xmalloc (sizeof (struct bfd_hash_table)));
 830           if (! bfd_hash_table_init (hash, bfd_hash_newfunc))
 831             einfo ("%F%P: bfd_hash_table_init failed: %E\n");
 832         }
 833
 834       if (bfd_hash_lookup (hash, name, false, false) != NULL)
 835         return true;
 836
 837       if (bfd_hash_lookup (hash, name, true, true) == NULL)
 838         einfo ("%F%P: bfd_hash_lookup failed: %E\n");
 839     }
 840
 841   /* We never print more than a reasonable number of errors in a row
 842      for a single symbol.  */
 843   if (error_name != (char *) NULL
 844       && strcmp (name, error_name) == 0)
 845     ++error_count;
 846   else
 847     {
 848       error_count = 0;
 849       if (error_name != (char *) NULL)
 850         free (error_name);
 851       error_name = buystring (name);
 852     }
 853
 854   if (section != NULL)
 855     {
 856       if (error_count < MAX_ERRORS_IN_A_ROW)
 857         einfo ("%X%C: undefined reference to `%T'\n",
 858                abfd, section, address, name);
 859       else if (error_count == MAX_ERRORS_IN_A_ROW)
 860         einfo ("%D: more undefined references to `%T' follow\n",
 861                abfd, section, address, name);
 862     }
 863   else
 864     {
 865       if (error_count < MAX_ERRORS_IN_A_ROW)
 866         einfo ("%X%B: undefined reference to `%T'\n",
 867                abfd, name);
 868       else if (error_count == MAX_ERRORS_IN_A_ROW)
 869         einfo ("%B: more undefined references to `%T' follow\n",
 870                abfd, name);
 871     }
 872
 873   return true;
 874 }
 875
 876 /* This is called when a reloc overflows.  */
 877
 878 /*ARGSUSED*/
 879 static boolean
 880 reloc_overflow (info, name, reloc_name, addend, abfd, section, address)
 881      struct bfd_link_info *info;
 882      const char *name;
 883      const char *reloc_name;
 884      bfd_vma addend;
 885      bfd *abfd;
 886      asection *section;
 887      bfd_vma address;
 888 {
 889   if (abfd == (bfd *) NULL)
 890     einfo ("%P%X: generated");
 891   else
 892     einfo ("%X%C:", abfd, section, address);
 893   einfo (" relocation truncated to fit: %s %T", reloc_name, name);
 894   if (addend != 0)
 895     einfo ("+%v", addend);
 896   einfo ("\n");
 897   return true;
 898 }
 899
 900 /* This is called when a dangerous relocation is made.  */
 901
 902 /*ARGSUSED*/
 903 static boolean
 904 reloc_dangerous (info, message, abfd, section, address)
 905      struct bfd_link_info *info;
 906      const char *message;
 907      bfd *abfd;
 908      asection *section;
 909      bfd_vma address;
 910 {
 911   if (abfd == (bfd *) NULL)
 912     einfo ("%P%X: generated");
 913   else
 914     einfo ("%X%C:", abfd, section, address);
 915   einfo ("dangerous relocation: %s\n", message);
 916   return true;
 917 }
 918
 919 /* This is called when a reloc is being generated attached to a symbol
 920    that is not being output.  */
 921
 922 /*ARGSUSED*/
 923 static boolean
 924 unattached_reloc (info, name, abfd, section, address)
 925      struct bfd_link_info *info;
 926      const char *name;
 927      bfd *abfd;
 928      asection *section;
 929      bfd_vma address;
 930 {
 931   if (abfd == (bfd *) NULL)
 932     einfo ("%P%X: generated");
 933   else
 934     einfo ("%X%C:", abfd, section, address);
 935   einfo (" reloc refers to symbol `%T' which is not being output\n", name);
 936   return true;
 937 }
 938
 939 /* This is called when a symbol in notice_hash is found.  Symbols are
 940    put in notice_hash using the -y option.  */
 941
 942 /*ARGSUSED*/
 943 static boolean
 944 notice_ysym (info, name, abfd, section, value)
 945      struct bfd_link_info *info;
 946      const char *name;
 947      bfd *abfd;
 948      asection *section;
 949      bfd_vma value;
 950 {
 951   einfo ("%B: %s %s\n", abfd,
 952          bfd_is_und_section (section) ? "reference to" : "definition of",
 953          name);
 954   return true;
 955 }