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