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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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 /* Use sbrk() except on specific OS types */
  50 #if !defined(__amigados__) && !defined(WINDOWS_NT)
  51 #define HAVE_SBRK
  52 #endif
  53
  54 static char *get_emulation PARAMS ((int, char **));
  55 static void set_scripts_dir PARAMS ((void));
  56
  57 /* EXPORTS */
  58
  59 char *default_target;
  60 const char *output_filename = "a.out";
  61
  62 /* Name this program was invoked by.  */
  63 char *program_name;
  64
  65 /* The file that we're creating */
  66 bfd *output_bfd = 0;
  67
  68 /* Set by -G argument, for MIPS ECOFF target.  */
  69 int g_switch_value = 8;
  70
  71 /* Nonzero means print names of input files as processed.  */
  72 boolean trace_files;
  73
  74 /* Nonzero means same, but note open failures, too.  */
  75 boolean trace_file_tries;
  76
  77 /* Nonzero means version number was printed, so exit successfully
  78    instead of complaining if no input files are given.  */
  79 boolean version_printed;
  80
  81 /* Nonzero means link in every member of an archive.  */
  82 boolean whole_archive;
  83
  84 args_type command_line;
  85
  86 ld_config_type config;
  87
  88 static boolean check_for_scripts_dir PARAMS ((char *dir));
  89 static boolean add_archive_element PARAMS ((struct bfd_link_info *, bfd *,
  90                                             const char *));
  91 static boolean multiple_definition PARAMS ((struct bfd_link_info *,
  92                                             const char *,
  93                                             bfd *, asection *, bfd_vma,
  94                                             bfd *, asection *, bfd_vma));
  95 static boolean multiple_common PARAMS ((struct bfd_link_info *,
  96                                         const char *, bfd *,
  97                                         enum bfd_link_hash_type, bfd_vma,
  98                                         bfd *, enum bfd_link_hash_type,
  99                                         bfd_vma));
 100 static boolean add_to_set PARAMS ((struct bfd_link_info *,
 101                                    struct bfd_link_hash_entry *,
 102                                    bfd_reloc_code_real_type,
 103                                    bfd *, asection *, bfd_vma));
 104 static boolean constructor_callback PARAMS ((struct bfd_link_info *,
 105                                              boolean constructor,
 106                                              const char *name,
 107                                              bfd *, asection *, bfd_vma));
 108 static boolean warning_callback PARAMS ((struct bfd_link_info *,
 109                                          const char *));
 110 static boolean undefined_symbol PARAMS ((struct bfd_link_info *,
 111                                          const char *, bfd *,
 112                                          asection *, bfd_vma));
 113 static boolean reloc_overflow PARAMS ((struct bfd_link_info *, const char *,
 114                                        const char *, bfd_vma,
 115                                        bfd *, asection *, bfd_vma));
 116 static boolean reloc_dangerous PARAMS ((struct bfd_link_info *, const char *,
 117                                         bfd *, asection *, bfd_vma));
 118 static boolean unattached_reloc PARAMS ((struct bfd_link_info *,
 119                                          const char *, bfd *, asection *,
 120                                          bfd_vma));
 121 static boolean notice_ysym PARAMS ((struct bfd_link_info *, const char *,
 122                                     bfd *, asection *, bfd_vma));
 123
 124 static struct bfd_link_callbacks link_callbacks =
 125 {
 126   add_archive_element,
 127   multiple_definition,
 128   multiple_common,
 129   add_to_set,
 130   constructor_callback,
 131   warning_callback,
 132   undefined_symbol,
 133   reloc_overflow,
 134   reloc_dangerous,
 135   unattached_reloc,
 136   notice_ysym
 137 };
 138
 139 struct bfd_link_info link_info;
 140 \f
 141 static void
 142 remove_output ()
 143 {
 144   if (output_filename)
 145     {
 146       if (output_bfd && output_bfd->iostream)
 147         fclose((FILE *)(output_bfd->iostream));
 148       if (delete_output_file_on_failure)
 149         unlink (output_filename);
 150     }
 151 }
 152
 153 int
 154 main (argc, argv)
 155      int argc;
 156      char **argv;
 157 {
 158   char *emulation;
 159   long start_time = get_run_time ();
 160
 161   program_name = argv[0];
 162   xmalloc_set_program_name (program_name);
 163
 164   START_PROGRESS (program_name, 0);
 165
 166   bfd_init ();
 167
 168   xatexit (remove_output);
 169
 170   /* Initialize the data about options.  */
 171   trace_files = trace_file_tries = version_printed = false;
 172   whole_archive = false;
 173   config.traditional_format = false;
 174   config.build_constructors = true;
 175   config.dynamic_link = false;
 176   command_line.force_common_definition = false;
 177   command_line.interpreter = NULL;
 178   command_line.rpath = NULL;
 179
 180   link_info.callbacks = &link_callbacks;
 181   link_info.relocateable = false;
 182   link_info.shared = false;
 183   link_info.symbolic = false;
 184   link_info.strip = strip_none;
 185   link_info.discard = discard_none;
 186   link_info.lprefix_len = 1;
 187   link_info.lprefix = "L";
 188   link_info.keep_memory = true;
 189   link_info.input_bfds = NULL;
 190   link_info.create_object_symbols_section = NULL;
 191   link_info.hash = NULL;
 192   link_info.keep_hash = NULL;
 193   link_info.notice_hash = NULL;
 194   link_info.subsystem = console;
 195   link_info.stack_heap_parameters.stack_defined = false;
 196   link_info.stack_heap_parameters.heap_defined  = false;
 197   link_info.stack_heap_parameters.stack_reserve = 0;
 198   link_info.stack_heap_parameters.stack_commit  = 0;
 199   link_info.stack_heap_parameters.heap_reserve  = 0;
 200   link_info.stack_heap_parameters.heap_commit   = 0;
 201
 202
 203   ldfile_add_arch ("");
 204
 205   config.make_executable = true;
 206   force_make_executable = false;
 207   config.magic_demand_paged = true;
 208   config.text_read_only = true;
 209   config.make_executable = true;
 210
 211   emulation = get_emulation (argc, argv);
 212   ldemul_choose_mode (emulation);
 213   default_target = ldemul_choose_target ();
 214   lang_init ();
 215   ldemul_before_parse ();
 216   lang_has_input_file = false;
 217   parse_args (argc, argv);
 218
 219   if (link_info.relocateable)
 220     {
 221       if (command_line.relax)
 222         einfo ("%P%F: -relax and -r may not be used together\n");
 223       if (link_info.shared)
 224         einfo ("%P%F: -r and -shared may not be used together\n");
 225     }
 226
 227   /* Treat ld -r -s as ld -r -S -x (i.e., strip all local symbols).  I
 228      don't see how else this can be handled, since in this case we
 229      must preserve all externally visible symbols.  */
 230   if (link_info.relocateable && link_info.strip == strip_all)
 231     {
 232       link_info.strip = strip_debugger;
 233       if (link_info.discard == discard_none)
 234         link_info.discard = discard_all;
 235     }
 236
 237   /* This essentially adds another -L directory so this must be done after
 238      the -L's in argv have been processed.  */
 239   set_scripts_dir ();
 240
 241   if (had_script == false)
 242     {
 243       /* Read the emulation's appropriate default script.  */
 244       int isfile;
 245       char *s = ldemul_get_script (&isfile);
 246
 247       if (isfile)
 248         ldfile_open_command_file (s);
 249       else
 250         {
 251           if (trace_file_tries)
 252             {
 253               info_msg ("using internal linker script:\n");
 254               info_msg ("==================================================\n");
 255               info_msg (s);
 256               info_msg ("\n==================================================\n");
 257             }
 258           lex_redirect (s);
 259         }
 260       parser_input = input_script;
 261       yyparse ();
 262     }
 263
 264   lang_final ();
 265
 266   if (lang_has_input_file == false)
 267     {
 268       if (version_printed)
 269         xexit (0);
 270       einfo ("%P%F: no input files\n");
 271     }
 272
 273   if (trace_files)
 274     {
 275       info_msg ("%P: mode %s\n", emulation);
 276     }
 277
 278   ldemul_after_parse ();
 279
 280
 281   if (config.map_filename)
 282     {
 283       if (strcmp (config.map_filename, "-") == 0)
 284         {
 285           config.map_file = stdout;
 286         }
 287       else
 288         {
 289           config.map_file = fopen (config.map_filename, FOPEN_WT);
 290           if (config.map_file == (FILE *) NULL)
 291             {
 292               bfd_set_error (bfd_error_system_call);
 293               einfo ("%P%F: cannot open map file %s: %E\n",
 294                      config.map_filename);
 295             }
 296         }
 297     }
 298
 299
 300   lang_process ();
 301
 302   /* Print error messages for any missing symbols, for any warning
 303      symbols, and possibly multiple definitions */
 304
 305
 306   if (config.text_read_only)
 307     {
 308       /* Look for a text section and mark the readonly attribute in it */
 309       asection *found = bfd_get_section_by_name (output_bfd, ".text");
 310
 311       if (found != (asection *) NULL)
 312         {
 313           found->flags |= SEC_READONLY;
 314         }
 315     }
 316
 317   if (link_info.relocateable)
 318     output_bfd->flags &= ~EXEC_P;
 319   else
 320     output_bfd->flags |= EXEC_P;
 321
 322   ldwrite ();
 323
 324   /* Even if we're producing relocateable output, some non-fatal errors should
 325      be reported in the exit status.  (What non-fatal errors, if any, do we
 326      want to ignore for relocateable output?)  */
 327
 328   if (config.make_executable == false && force_make_executable == false)
 329     {
 330       if (trace_files == true)
 331         {
 332           einfo ("%P: link errors found, deleting executable `%s'\n",
 333                  output_filename);
 334         }
 335
 336       if (output_bfd->iostream)
 337         fclose ((FILE *) (output_bfd->iostream));
 338
 339       unlink (output_filename);
 340       xexit (1);
 341     }
 342   else
 343     {
 344       if (! bfd_close (output_bfd))
 345         einfo ("%F%B: final close failed: %E\n", output_bfd);
 346     }
 347
 348   END_PROGRESS (program_name);
 349
 350   if (config.stats)
 351     {
 352       extern char **environ;
 353 #ifdef HAVE_SBRK
 354       char *lim = (char *) sbrk (0);
 355 #endif
 356       long run_time = get_run_time () - start_time;
 357
 358       fprintf (stderr, "%s: total time in link: %ld.%06ld\n",
 359                program_name, run_time / 1000000, run_time % 1000000);
 360 #ifdef HAVE_SBRK
 361       fprintf (stderr, "%s: data size %ld\n", program_name,
 362                (long) (lim - (char *) &environ));
 363 #endif
 364     }
 365
 366   /* Prevent remove_output from doing anything, after a successful link.  */
 367   output_filename = NULL;
 368
 369   xexit (0);
 370   return 0;
 371 }
 372
 373 /* We need to find any explicitly given emulation in order to initialize the
 374    state that's needed by the lex&yacc argument parser (parse_args).  */
 375
 376 static char *
 377 get_emulation (argc, argv)
 378      int argc;
 379      char **argv;
 380 {
 381   char *emulation;
 382   int i;
 383
 384   emulation = (char *) getenv (EMULATION_ENVIRON);
 385   if (emulation == NULL)
 386     emulation = DEFAULT_EMULATION;
 387
 388   for (i = 1; i < argc; i++)
 389     {
 390       if (!strncmp (argv[i], "-m", 2))
 391         {
 392           if (argv[i][2] == '\0')
 393             {
 394               /* -m EMUL */
 395               if (i < argc - 1)
 396                 {
 397                   emulation = argv[i + 1];
 398                   i++;
 399                 }
 400               else
 401                 {
 402                   einfo("%P%F: missing argument to -m\n");
 403                 }
 404             }
 405           else if (strcmp (argv[i], "-mips1") == 0
 406                    || strcmp (argv[i], "-mips2") == 0
 407                    || strcmp (argv[i], "-mips3") == 0)
 408             {
 409               /* FIXME: The arguments -mips1, -mips2 and -mips3 are
 410                  passed to the linker by some MIPS compilers.  They
 411                  generally tell the linker to use a slightly different
 412                  library path.  Perhaps someday these should be
 413                  implemented as emulations; until then, we just ignore
 414                  the arguments and hope that nobody ever creates
 415                  emulations named ips1, ips2 or ips3.  */
 416             }
 417           else if (strcmp (argv[i], "-m486") == 0)
 418             {
 419               /* FIXME: The argument -m486 is passed to the linker on
 420                  some Linux systems.  Hope that nobody creates an
 421                  emulation named 486.  */
 422             }
 423           else
 424             {
 425               /* -mEMUL */
 426               emulation = &argv[i][2];
 427             }
 428         }
 429     }
 430
 431   return emulation;
 432 }
 433
 434 /* If directory DIR contains an "ldscripts" subdirectory,
 435    add DIR to the library search path and return true,
 436    else return false.  */
 437
 438 static boolean
 439 check_for_scripts_dir (dir)
 440      char *dir;
 441 {
 442   size_t dirlen;
 443   char *buf;
 444   struct stat s;
 445   boolean res;
 446
 447   dirlen = strlen (dir);
 448   /* sizeof counts the terminating NUL.  */
 449   buf = (char *) xmalloc (dirlen + sizeof("/ldscripts"));
 450   sprintf (buf, "%s/ldscripts", dir);
 451
 452   res = stat (buf, &s) == 0 && S_ISDIR (s.st_mode);
 453   free (buf);
 454   if (res)
 455     ldfile_add_library_path (dir, false);
 456   return res;
 457 }
 458
 459 /* Set the default directory for finding script files.
 460    Libraries will be searched for here too, but that's ok.
 461    We look for the "ldscripts" directory in:
 462
 463    SCRIPTDIR (passed from Makefile)
 464    the dir where this program is (for using it from the build tree)
 465    the dir where this program is/../lib (for installing the tool suite elsewhere) */
 466
 467 static void
 468 set_scripts_dir ()
 469 {
 470   char *end, *dir;
 471   size_t dirlen;
 472
 473   if (check_for_scripts_dir (SCRIPTDIR))
 474     return;                     /* We've been installed normally.  */
 475
 476   /* Look for "ldscripts" in the dir where our binary is.  */
 477   end = strrchr (program_name, '/');
 478   if (end)
 479     {
 480       dirlen = end - program_name;
 481       /* Make a copy of program_name in dir.
 482          Leave room for later "/../lib".  */
 483       dir = (char *) xmalloc (dirlen + 8);
 484       strncpy (dir, program_name, dirlen);
 485       dir[dirlen] = '\0';
 486     }
 487   else
 488     {
 489       dirlen = 1;
 490       dir = (char *) xmalloc (dirlen + 8);
 491       strcpy (dir, ".");
 492     }
 493
 494   if (check_for_scripts_dir (dir))
 495     return;                     /* Don't free dir.  */
 496
 497   /* Look for "ldscripts" in <the dir where our binary is>/../lib.  */
 498   strcpy (dir + dirlen, "/../lib");
 499   if (check_for_scripts_dir (dir))
 500     return;
 501
 502   free (dir);                   /* Well, we tried.  */
 503 }
 504
 505 void
 506 add_ysym (name)
 507      const char *name;
 508 {
 509   if (link_info.notice_hash == (struct bfd_hash_table *) NULL)
 510     {
 511       link_info.notice_hash = ((struct bfd_hash_table *)
 512                                xmalloc (sizeof (struct bfd_hash_table)));
 513       if (! bfd_hash_table_init_n (link_info.notice_hash,
 514                                    bfd_hash_newfunc,
 515                                    61))
 516         einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 517     }
 518
 519   if (bfd_hash_lookup (link_info.notice_hash, name, true, true)
 520       == (struct bfd_hash_entry *) NULL)
 521     einfo ("%P%F: bfd_hash_lookup failed: %E\n");
 522 }
 523
 524 /* Handle the -retain-symbols-file option.  */
 525
 526 void
 527 add_keepsyms_file (filename)
 528      const char *filename;
 529 {
 530   FILE *file;
 531   char *buf;
 532   size_t bufsize;
 533   int c;
 534
 535   if (link_info.strip == strip_some)
 536     einfo ("%X%P: error: duplicate retain-symbols-file\n");
 537
 538   file = fopen (filename, "r");
 539   if (file == (FILE *) NULL)
 540     {
 541       bfd_set_error (bfd_error_system_call);
 542       einfo ("%X%P: %s: %E", filename);
 543       return;
 544     }
 545
 546   link_info.keep_hash = ((struct bfd_hash_table *)
 547                          xmalloc (sizeof (struct bfd_hash_table)));
 548   if (! bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc))
 549     einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 550
 551   bufsize = 100;
 552   buf = (char *) xmalloc (bufsize);
 553
 554   c = getc (file);
 555   while (c != EOF)
 556     {
 557       while (isspace (c))
 558         c = getc (file);
 559
 560       if (c != EOF)
 561         {
 562           size_t len = 0;
 563
 564           while (! isspace (c) && c != EOF)
 565             {
 566               buf[len] = c;
 567               ++len;
 568               if (len >= bufsize)
 569                 {
 570                   bufsize *= 2;
 571                   buf = xrealloc (buf, bufsize);
 572                 }
 573               c = getc (file);
 574             }
 575
 576           buf[len] = '\0';
 577
 578           if (bfd_hash_lookup (link_info.keep_hash, buf, true, true)
 579               == (struct bfd_hash_entry *) NULL)
 580             einfo ("%P%F: bfd_hash_lookup for insertion failed: %E");
 581         }
 582     }
 583
 584   if (link_info.strip != strip_none)
 585     einfo ("%P: `-retain-symbols-file' overrides `-s' and `-S'\n");
 586
 587   link_info.strip = strip_some;
 588 }
 589 \f
 590 /* Callbacks from the BFD linker routines.  */
 591
 592 /* This is called when BFD has decided to include an archive member in
 593    a link.  */
 594
 595 /*ARGSUSED*/
 596 static boolean
 597 add_archive_element (info, abfd, name)
 598      struct bfd_link_info *info;
 599      bfd *abfd;
 600      const char *name;
 601 {
 602   lang_input_statement_type *input;
 603
 604   input = ((lang_input_statement_type *)
 605            xmalloc ((bfd_size_type) sizeof (lang_input_statement_type)));
 606   input->filename = abfd->filename;
 607   input->local_sym_name = abfd->filename;
 608   input->the_bfd = abfd;
 609   input->asymbols = NULL;
 610   input->next = NULL;
 611   input->just_syms_flag = false;
 612   input->loaded = false;
 613   input->search_dirs_flag = false;
 614
 615   /* FIXME: The following fields are not set: header.next,
 616      header.type, closed, passive_position, symbol_count,
 617      next_real_file, is_archive, target, real, common_section,
 618      common_output_section, complained.  This bit of code is from the
 619      old decode_library_subfile function.  I don't know whether any of
 620      those fields matters.  */
 621
 622   ldlang_add_file (input);
 623
 624   if (config.map_file != (FILE *) NULL)
 625     minfo ("%s needed due to %T\n", abfd->filename, name);
 626
 627   if (trace_files || trace_file_tries)
 628     info_msg ("%I\n", input);
 629
 630   return true;
 631 }
 632
 633 /* This is called when BFD has discovered a symbol which is defined
 634    multiple times.  */
 635
 636 /*ARGSUSED*/
 637 static boolean
 638 multiple_definition (info, name, obfd, osec, oval, nbfd, nsec, nval)
 639      struct bfd_link_info *info;
 640      const char *name;
 641      bfd *obfd;
 642      asection *osec;
 643      bfd_vma oval;
 644      bfd *nbfd;
 645      asection *nsec;
 646      bfd_vma nval;
 647 {
 648   einfo ("%X%C: multiple definition of `%T'\n",
 649          nbfd, nsec, nval, name);
 650   if (obfd != (bfd *) NULL)
 651     einfo ("%D: first defined here\n", obfd, osec, oval);
 652   return true;
 653 }
 654
 655 /* This is called when there is a definition of a common symbol, or
 656    when a common symbol is found for a symbol that is already defined,
 657    or when two common symbols are found.  We only do something if
 658    -warn-common was used.  */
 659
 660 /*ARGSUSED*/
 661 static boolean
 662 multiple_common (info, name, obfd, otype, osize, nbfd, ntype, nsize)
 663      struct bfd_link_info *info;
 664      const char *name;
 665      bfd *obfd;
 666      enum bfd_link_hash_type otype;
 667      bfd_vma osize;
 668      bfd *nbfd;
 669      enum bfd_link_hash_type ntype;
 670      bfd_vma nsize;
 671 {
 672   if (! config.warn_common)
 673     return true;
 674
 675   if (ntype == bfd_link_hash_defined
 676       || ntype == bfd_link_hash_defweak
 677       || ntype == bfd_link_hash_indirect)
 678     {
 679       ASSERT (otype == bfd_link_hash_common);
 680       einfo ("%B: warning: definition of `%T' overriding common\n",
 681              nbfd, name);
 682       if (obfd != NULL)
 683         einfo ("%B: warning: common is here\n", obfd);
 684     }
 685   else if (otype == bfd_link_hash_defined
 686            || otype == bfd_link_hash_defweak
 687            || otype == bfd_link_hash_indirect)
 688     {
 689       ASSERT (ntype == bfd_link_hash_common);
 690       einfo ("%B: warning: common of `%T' overridden by definition\n",
 691              nbfd, name);
 692       if (obfd != NULL)
 693         einfo ("%B: warning: defined here\n", obfd);
 694     }
 695   else
 696     {
 697       ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
 698       if (osize > nsize)
 699         {
 700           einfo ("%B: warning: common of `%T' overridden by larger common\n",
 701                  nbfd, name);
 702           if (obfd != NULL)
 703             einfo ("%B: warning: larger common is here\n", obfd);
 704         }
 705       else if (nsize > osize)
 706         {
 707           einfo ("%B: warning: common of `%T' overriding smaller common\n",
 708                  nbfd, name);
 709           if (obfd != NULL)
 710             einfo ("%B: warning: smaller common is here\n", obfd);
 711         }
 712       else
 713         {
 714           einfo ("%B: warning: multiple common of `%T'\n", nbfd, name);
 715           if (obfd != NULL)
 716             einfo ("%B: warning: previous common is here\n", obfd);
 717         }
 718     }
 719
 720   return true;
 721 }
 722
 723 /* This is called when BFD has discovered a set element.  H is the
 724    entry in the linker hash table for the set.  SECTION and VALUE
 725    represent a value which should be added to the set.  */
 726
 727 /*ARGSUSED*/
 728 static boolean
 729 add_to_set (info, h, reloc, abfd, section, value)
 730      struct bfd_link_info *info;
 731      struct bfd_link_hash_entry *h;
 732      bfd_reloc_code_real_type reloc;
 733      bfd *abfd;
 734      asection *section;
 735      bfd_vma value;
 736 {
 737   if (! config.build_constructors)
 738     return true;
 739
 740   ldctor_add_set_entry (h, reloc, section, value);
 741
 742   if (h->type == bfd_link_hash_new)
 743     {
 744       h->type = bfd_link_hash_undefined;
 745       h->u.undef.abfd = abfd;
 746       /* We don't call bfd_link_add_undef to add this to the list of
 747          undefined symbols because we are going to define it
 748          ourselves.  */
 749     }
 750
 751   return true;
 752 }
 753
 754 /* This is called when BFD has discovered a constructor.  This is only
 755    called for some object file formats--those which do not handle
 756    constructors in some more clever fashion.  This is similar to
 757    adding an element to a set, but less general.  */
 758
 759 static boolean
 760 constructor_callback (info, constructor, name, abfd, section, value)
 761      struct bfd_link_info *info;
 762      boolean constructor;
 763      const char *name;
 764      bfd *abfd;
 765      asection *section;
 766      bfd_vma value;
 767 {
 768   char *set_name;
 769   char *s;
 770   struct bfd_link_hash_entry *h;
 771
 772   if (! config.build_constructors)
 773     return true;
 774
 775   /* Ensure that BFD_RELOC_CTOR exists now, so that we can give a
 776      useful error message.  */
 777   if (bfd_reloc_type_lookup (output_bfd, BFD_RELOC_CTOR) == NULL)
 778     einfo ("%P%F: BFD backend error: BFD_RELOC_CTOR unsupported");
 779
 780   set_name = (char *) alloca (1 + sizeof "__CTOR_LIST__");
 781   s = set_name;
 782   if (bfd_get_symbol_leading_char (abfd) != '\0')
 783     *s++ = bfd_get_symbol_leading_char (abfd);
 784   if (constructor)
 785     strcpy (s, "__CTOR_LIST__");
 786   else
 787     strcpy (s, "__DTOR_LIST__");
 788
 789   if (config.map_file != (FILE *) NULL)
 790     fprintf (config.map_file,
 791              "Adding %s to constructor/destructor set %s\n", name, set_name);
 792
 793   h = bfd_link_hash_lookup (info->hash, set_name, true, true, true);
 794   if (h == (struct bfd_link_hash_entry *) NULL)
 795     einfo ("%P%F: bfd_link_hash_lookup failed: %E");
 796   if (h->type == bfd_link_hash_new)
 797     {
 798       h->type = bfd_link_hash_undefined;
 799       h->u.undef.abfd = abfd;
 800       /* We don't call bfd_link_add_undef to add this to the list of
 801          undefined symbols because we are going to define it
 802          ourselves.  */
 803     }
 804
 805   ldctor_add_set_entry (h, BFD_RELOC_CTOR, section, value);
 806   return true;
 807 }
 808
 809 /* This is called when there is a reference to a warning symbol.  */
 810
 811 /*ARGSUSED*/
 812 static boolean
 813 warning_callback (info, warning)
 814      struct bfd_link_info *info;
 815      const char *warning;
 816 {
 817   einfo ("%P: %s\n", warning);
 818   return true;
 819 }
 820
 821 /* This is called when an undefined symbol is found.  */
 822
 823 /*ARGSUSED*/
 824 static boolean
 825 undefined_symbol (info, name, abfd, section, address)
 826      struct bfd_link_info *info;
 827      const char *name;
 828      bfd *abfd;
 829      asection *section;
 830      bfd_vma address;
 831 {
 832   static char *error_name;
 833   static unsigned int error_count;
 834
 835 #define MAX_ERRORS_IN_A_ROW 5
 836
 837   if (config.warn_once)
 838     {
 839       static struct bfd_hash_table *hash;
 840
 841       /* Only warn once about a particular undefined symbol.  */
 842
 843       if (hash == NULL)
 844         {
 845           hash = ((struct bfd_hash_table *)
 846                   xmalloc (sizeof (struct bfd_hash_table)));
 847           if (! bfd_hash_table_init (hash, bfd_hash_newfunc))
 848             einfo ("%F%P: bfd_hash_table_init failed: %E\n");
 849         }
 850
 851       if (bfd_hash_lookup (hash, name, false, false) != NULL)
 852         return true;
 853
 854       if (bfd_hash_lookup (hash, name, true, true) == NULL)
 855         einfo ("%F%P: bfd_hash_lookup failed: %E\n");
 856     }
 857
 858   /* We never print more than a reasonable number of errors in a row
 859      for a single symbol.  */
 860   if (error_name != (char *) NULL
 861       && strcmp (name, error_name) == 0)
 862     ++error_count;
 863   else
 864     {
 865       error_count = 0;
 866       if (error_name != (char *) NULL)
 867         free (error_name);
 868       error_name = buystring (name);
 869     }
 870
 871   if (section != NULL)
 872     {
 873       if (error_count < MAX_ERRORS_IN_A_ROW)
 874         einfo ("%X%C: undefined reference to `%T'\n",
 875                abfd, section, address, name);
 876       else if (error_count == MAX_ERRORS_IN_A_ROW)
 877         einfo ("%D: more undefined references to `%T' follow\n",
 878                abfd, section, address, name);
 879     }
 880   else
 881     {
 882       if (error_count < MAX_ERRORS_IN_A_ROW)
 883         einfo ("%X%B: undefined reference to `%T'\n",
 884                abfd, name);
 885       else if (error_count == MAX_ERRORS_IN_A_ROW)
 886         einfo ("%B: more undefined references to `%T' follow\n",
 887                abfd, name);
 888     }
 889
 890   return true;
 891 }
 892
 893 /* This is called when a reloc overflows.  */
 894
 895 /*ARGSUSED*/
 896 static boolean
 897 reloc_overflow (info, name, reloc_name, addend, abfd, section, address)
 898      struct bfd_link_info *info;
 899      const char *name;
 900      const char *reloc_name;
 901      bfd_vma addend;
 902      bfd *abfd;
 903      asection *section;
 904      bfd_vma address;
 905 {
 906   if (abfd == (bfd *) NULL)
 907     einfo ("%P%X: generated");
 908   else
 909     einfo ("%X%C:", abfd, section, address);
 910   einfo (" relocation truncated to fit: %s %T", reloc_name, name);
 911   if (addend != 0)
 912     einfo ("+%v", addend);
 913   einfo ("\n");
 914   return true;
 915 }
 916
 917 /* This is called when a dangerous relocation is made.  */
 918
 919 /*ARGSUSED*/
 920 static boolean
 921 reloc_dangerous (info, message, abfd, section, address)
 922      struct bfd_link_info *info;
 923      const char *message;
 924      bfd *abfd;
 925      asection *section;
 926      bfd_vma address;
 927 {
 928   if (abfd == (bfd *) NULL)
 929     einfo ("%P%X: generated");
 930   else
 931     einfo ("%X%C:", abfd, section, address);
 932   einfo ("dangerous relocation: %s\n", message);
 933   return true;
 934 }
 935
 936 /* This is called when a reloc is being generated attached to a symbol
 937    that is not being output.  */
 938
 939 /*ARGSUSED*/
 940 static boolean
 941 unattached_reloc (info, name, abfd, section, address)
 942      struct bfd_link_info *info;
 943      const char *name;
 944      bfd *abfd;
 945      asection *section;
 946      bfd_vma address;
 947 {
 948   if (abfd == (bfd *) NULL)
 949     einfo ("%P%X: generated");
 950   else
 951     einfo ("%X%C:", abfd, section, address);
 952   einfo (" reloc refers to symbol `%T' which is not being output\n", name);
 953   return true;
 954 }
 955
 956 /* This is called when a symbol in notice_hash is found.  Symbols are
 957    put in notice_hash using the -y option.  */
 958
 959 /*ARGSUSED*/
 960 static boolean
 961 notice_ysym (info, name, abfd, section, value)
 962      struct bfd_link_info *info;
 963      const char *name;
 964      bfd *abfd;
 965      asection *section;
 966      bfd_vma value;
 967 {
 968   einfo ("%B: %s %s\n", abfd,
 969          bfd_is_und_section (section) ? "reference to" : "definition of",
 970          name);
 971   return true;
 972 }