ld/ldmain.c

   1 /* Main program of GNU linker.
   2    Copyright (C) 1991, 1993, 1994 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 extern int main PARAMS ((int, char **));
 136
 137 int
 138 main (argc, argv)
 139      int argc;
 140      char **argv;
 141 {
 142   char *emulation;
 143   long start_time = get_run_time ();
 144
 145   program_name = argv[0];
 146
 147   bfd_init ();
 148
 149   /* Initialize the data about options.  */
 150   trace_files = trace_file_tries = version_printed = false;
 151   write_map = false;
 152   config.build_constructors = true;
 153   command_line.force_common_definition = false;
 154
 155   link_info.callbacks = &link_callbacks;
 156   link_info.relocateable = false;
 157   link_info.strip = strip_none;
 158   link_info.discard = discard_none;
 159   link_info.lprefix_len = 1;
 160   link_info.lprefix = "L";
 161   link_info.keep_memory = true;
 162   link_info.input_bfds = NULL;
 163   link_info.create_object_symbols_section = NULL;
 164   link_info.hash = NULL;
 165   link_info.keep_hash = NULL;
 166   link_info.notice_hash = NULL;
 167
 168   ldfile_add_arch ("");
 169
 170   config.make_executable = true;
 171   force_make_executable = false;
 172   config.magic_demand_paged = true;
 173   config.text_read_only = true;
 174   config.make_executable = true;
 175
 176   emulation = get_emulation (argc, argv);
 177   ldemul_choose_mode (emulation);
 178   default_target = ldemul_choose_target ();
 179   lang_init ();
 180   ldemul_before_parse ();
 181   lang_has_input_file = false;
 182   parse_args (argc, argv);
 183
 184   /* This essentially adds another -L directory so this must be done after
 185      the -L's in argv have been processed.  */
 186   set_scripts_dir ();
 187
 188   if (had_script == false)
 189     {
 190       /* Read the emulation's appropriate default script.  */
 191       int isfile;
 192       char *s = ldemul_get_script (&isfile);
 193
 194       if (isfile)
 195         {
 196           /* sizeof counts the terminating NUL.  */
 197           size_t size = strlen (s) + sizeof ("-T ");
 198           char *buf = (char *) ldmalloc(size);
 199           sprintf (buf, "-T %s", s);
 200           parse_line (buf, 0);
 201           free (buf);
 202         }
 203       else
 204         parse_line (s, 1);
 205     }
 206
 207   if (link_info.relocateable && command_line.relax)
 208     {
 209       einfo ("%P%F: -relax and -r may not be used together\n");
 210     }
 211   lang_final ();
 212
 213   if (lang_has_input_file == false)
 214     {
 215       if (version_printed)
 216         exit (0);
 217       einfo ("%P%F: no input files\n");
 218     }
 219
 220   if (trace_files)
 221     {
 222       info_msg ("%P: mode %s\n", emulation);
 223     }
 224
 225   ldemul_after_parse ();
 226
 227
 228   if (config.map_filename)
 229     {
 230       if (strcmp (config.map_filename, "-") == 0)
 231         {
 232           config.map_file = stdout;
 233         }
 234       else
 235         {
 236           config.map_file = fopen (config.map_filename, FOPEN_WT);
 237           if (config.map_file == (FILE *) NULL)
 238             {
 239               einfo ("%P%F: cannot open map file %s: %E\n",
 240                      config.map_filename);
 241             }
 242         }
 243     }
 244
 245
 246   lang_process ();
 247
 248   /* Print error messages for any missing symbols, for any warning
 249      symbols, and possibly multiple definitions */
 250
 251
 252   if (config.text_read_only)
 253     {
 254       /* Look for a text section and mark the readonly attribute in it */
 255       asection *found = bfd_get_section_by_name (output_bfd, ".text");
 256
 257       if (found != (asection *) NULL)
 258         {
 259           found->flags |= SEC_READONLY;
 260         }
 261     }
 262
 263   if (link_info.relocateable)
 264     output_bfd->flags &= ~EXEC_P;
 265   else
 266     output_bfd->flags |= EXEC_P;
 267
 268   ldwrite ();
 269
 270   /* Even if we're producing relocateable output, some non-fatal errors should
 271      be reported in the exit status.  (What non-fatal errors, if any, do we
 272      want to ignore for relocateable output?)  */
 273
 274   if (config.make_executable == false && force_make_executable == false)
 275     {
 276       if (trace_files == true)
 277         {
 278           einfo ("%P: link errors found, deleting executable `%s'\n",
 279                  output_filename);
 280         }
 281
 282       if (output_bfd->iostream)
 283         fclose ((FILE *) (output_bfd->iostream));
 284
 285       unlink (output_filename);
 286       exit (1);
 287     }
 288   else
 289     {
 290       bfd_close (output_bfd);
 291     }
 292
 293   if (config.stats)
 294     {
 295       extern char **environ;
 296       char *lim = (char *) sbrk (0);
 297       long run_time = get_run_time () - start_time;
 298
 299       fprintf (stderr, "%s: total time in link: %d.%06d\n",
 300                program_name, run_time / 1000000, run_time % 1000000);
 301       fprintf (stderr, "%s: data size %ld\n", program_name,
 302                (long) (lim - (char *) &environ));
 303     }
 304
 305   exit (0);
 306   return 0;
 307 }
 308
 309 /* We need to find any explicitly given emulation in order to initialize the
 310    state that's needed by the lex&yacc argument parser (parse_args).  */
 311
 312 static char *
 313 get_emulation (argc, argv)
 314      int argc;
 315      char **argv;
 316 {
 317   char *emulation;
 318   int i;
 319
 320   emulation = (char *) getenv (EMULATION_ENVIRON);
 321   if (emulation == NULL)
 322     emulation = DEFAULT_EMULATION;
 323
 324   for (i = 1; i < argc; i++)
 325     {
 326       if (!strncmp (argv[i], "-m", 2))
 327         {
 328           if (argv[i][2] == '\0')
 329             {
 330               /* -m EMUL */
 331               if (i < argc - 1)
 332                 {
 333                   emulation = argv[i + 1];
 334                   i++;
 335                 }
 336               else
 337                 {
 338                   einfo("%P%F: missing argument to -m\n");
 339                 }
 340             }
 341           else if (strcmp (argv[i], "-mips1") == 0
 342                    || strcmp (argv[i], "-mips2") == 0
 343                    || strcmp (argv[i], "-mips3") == 0)
 344             {
 345               /* FIXME: The arguments -mips1, -mips2 and -mips3 are
 346                  passed to the linker by some MIPS compilers.  They
 347                  generally tell the linker to use a slightly different
 348                  library path.  Perhaps someday these should be
 349                  implemented as emulations; until then, we just ignore
 350                  the arguments and hope that nobody ever creates
 351                  emulations named ips1, ips2 or ips3.  */
 352             }
 353           else
 354             {
 355               /* -mEMUL */
 356               emulation = &argv[i][2];
 357             }
 358         }
 359     }
 360
 361   return emulation;
 362 }
 363
 364 /* If directory DIR contains an "ldscripts" subdirectory,
 365    add DIR to the library search path and return true,
 366    else return false.  */
 367
 368 static boolean
 369 check_for_scripts_dir (dir)
 370      char *dir;
 371 {
 372   size_t dirlen;
 373   char *buf;
 374   struct stat s;
 375   boolean res;
 376
 377   dirlen = strlen (dir);
 378   /* sizeof counts the terminating NUL.  */
 379   buf = (char *) ldmalloc (dirlen + sizeof("/ldscripts"));
 380   sprintf (buf, "%s/ldscripts", dir);
 381
 382   res = stat (buf, &s) == 0 && S_ISDIR (s.st_mode);
 383   free (buf);
 384   if (res)
 385     ldfile_add_library_path (dir);
 386   return res;
 387 }
 388
 389 /* Set the default directory for finding script files.
 390    Libraries will be searched for here too, but that's ok.
 391    We look for the "ldscripts" directory in:
 392
 393    SCRIPTDIR (passed from Makefile)
 394    the dir where this program is (for using it from the build tree)
 395    the dir where this program is/../lib (for installing the tool suite elsewhere) */
 396
 397 static void
 398 set_scripts_dir ()
 399 {
 400   char *end, *dir;
 401   size_t dirlen;
 402
 403   if (check_for_scripts_dir (SCRIPTDIR))
 404     return;                     /* We've been installed normally.  */
 405
 406   /* Look for "ldscripts" in the dir where our binary is.  */
 407   end = strrchr (program_name, '/');
 408   if (end)
 409     {
 410       dirlen = end - program_name;
 411       /* Make a copy of program_name in dir.
 412          Leave room for later "/../lib".  */
 413       dir = (char *) ldmalloc (dirlen + 8);
 414       strncpy (dir, program_name, dirlen);
 415       dir[dirlen] = '\0';
 416     }
 417   else
 418     {
 419       dirlen = 1;
 420       dir = (char *) ldmalloc (dirlen + 8);
 421       strcpy (dir, ".");
 422     }
 423
 424   if (check_for_scripts_dir (dir))
 425     return;                     /* Don't free dir.  */
 426
 427   /* Look for "ldscripts" in <the dir where our binary is>/../lib.  */
 428   strcpy (dir + dirlen, "/../lib");
 429   if (check_for_scripts_dir (dir))
 430     return;
 431
 432   free (dir);                   /* Well, we tried.  */
 433 }
 434
 435 void
 436 add_ysym (name)
 437      const char *name;
 438 {
 439   if (link_info.notice_hash == (struct bfd_hash_table *) NULL)
 440     {
 441       link_info.notice_hash = ((struct bfd_hash_table *)
 442                                ldmalloc (sizeof (struct bfd_hash_table)));
 443       if (! bfd_hash_table_init_n (link_info.notice_hash,
 444                                    bfd_hash_newfunc,
 445                                    61))
 446         einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 447     }
 448
 449   if (bfd_hash_lookup (link_info.notice_hash, name, true, true)
 450       == (struct bfd_hash_entry *) NULL)
 451     einfo ("%P%F: bfd_hash_lookup failed: %E\n");
 452 }
 453
 454 /* Handle the -retain-symbols-file option.  */
 455
 456 void
 457 add_keepsyms_file (filename)
 458      const char *filename;
 459 {
 460   FILE *file;
 461   char *buf;
 462   size_t bufsize;
 463   int c;
 464
 465   if (link_info.strip == strip_some)
 466     einfo ("%X%P: error: duplicate retain-symbols-file\n");
 467
 468   file = fopen (filename, "r");
 469   if (file == (FILE *) NULL)
 470     {
 471       bfd_error = system_call_error;
 472       einfo ("%X%P: %s: %E", filename);
 473       return;
 474     }
 475
 476   link_info.keep_hash = ((struct bfd_hash_table *)
 477                          ldmalloc (sizeof (struct bfd_hash_table)));
 478   if (! bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc))
 479     einfo ("%P%F: bfd_hash_table_init failed: %E\n");
 480
 481   bufsize = 100;
 482   buf = (char *) ldmalloc (bufsize);
 483
 484   c = getc (file);
 485   while (c != EOF)
 486     {
 487       while (isspace (c))
 488         c = getc (file);
 489
 490       if (c != EOF)
 491         {
 492           size_t len = 0;
 493
 494           while (! isspace (c) && c != EOF)
 495             {
 496               buf[len] = c;
 497               ++len;
 498               if (len >= bufsize)
 499                 {
 500                   bufsize *= 2;
 501                   buf = ldrealloc (buf, bufsize);
 502                 }
 503               c = getc (file);
 504             }
 505
 506           buf[len] = '\0';
 507
 508           if (bfd_hash_lookup (link_info.keep_hash, buf, true, true)
 509               == (struct bfd_hash_entry *) NULL)
 510             einfo ("%P%F: bfd_hash_lookup for insertion failed: %E");
 511         }
 512     }
 513
 514   if (link_info.strip != strip_none)
 515     einfo ("%P: `-retain-symbols-file' overrides `-s' and `-S'\n");
 516
 517   link_info.strip = strip_some;
 518 }
 519 \f
 520 /* Callbacks from the BFD linker routines.  */
 521
 522 /* This is called when BFD has decided to include an archive member in
 523    a link.  */
 524
 525 /*ARGSUSED*/
 526 static boolean
 527 add_archive_element (info, abfd, name)
 528      struct bfd_link_info *info;
 529      bfd *abfd;
 530      const char *name;
 531 {
 532   lang_input_statement_type *input;
 533
 534   input = ((lang_input_statement_type *)
 535            ldmalloc ((bfd_size_type) sizeof (lang_input_statement_type)));
 536   input->filename = abfd->filename;
 537   input->local_sym_name = abfd->filename;
 538   input->the_bfd = abfd;
 539   input->asymbols = NULL;
 540   input->subfiles = NULL;
 541   input->next = NULL;
 542   input->just_syms_flag = false;
 543   input->loaded = false;
 544   input->chain = NULL;
 545
 546   /* FIXME: This is wrong.  It should point to an entry for the
 547      archive itself.  However, it doesn't seem to matter.  */
 548   input->superfile = NULL;
 549
 550   /* FIXME: The following fields are not set: header.next,
 551      header.type, closed, passive_position, symbol_count, total_size,
 552      next_real_file, is_archive, search_dirs_flag, target, real,
 553      common_section, common_output_section, complained.  This bit of
 554      code is from the old decode_library_subfile function.  I don't
 555      know whether any of those fields matters.  */
 556
 557   ldlang_add_file (input);
 558
 559   if (write_map)
 560     info_msg ("%s needed due to %T\n", abfd->filename, name);
 561
 562   if (trace_files || trace_file_tries)
 563     info_msg ("%I\n", input);
 564
 565   return true;
 566 }
 567
 568 /* This is called when BFD has discovered a symbol which is defined
 569    multiple times.  */
 570
 571 /*ARGSUSED*/
 572 static boolean
 573 multiple_definition (info, name, obfd, osec, oval, nbfd, nsec, nval)
 574      struct bfd_link_info *info;
 575      const char *name;
 576      bfd *obfd;
 577      asection *osec;
 578      bfd_vma oval;
 579      bfd *nbfd;
 580      asection *nsec;
 581      bfd_vma nval;
 582 {
 583   einfo ("%X%C: multiple definition of `%T'\n",
 584          nbfd, nsec, nval, name);
 585   if (obfd != (bfd *) NULL)
 586     einfo ("%C: first defined here\n", obfd, osec, oval);
 587   return true;
 588 }
 589
 590 /* This is called when there is a definition of a common symbol, or
 591    when a common symbol is found for a symbol that is already defined,
 592    or when two common symbols are found.  We only do something if
 593    -warn-common was used.  */
 594
 595 /*ARGSUSED*/
 596 static boolean
 597 multiple_common (info, name, obfd, otype, osize, nbfd, ntype, nsize)
 598      struct bfd_link_info *info;
 599      const char *name;
 600      bfd *obfd;
 601      enum bfd_link_hash_type otype;
 602      bfd_vma osize;
 603      bfd *nbfd;
 604      enum bfd_link_hash_type ntype;
 605      bfd_vma nsize;
 606 {
 607   if (! config.warn_common)
 608     return true;
 609
 610   if (ntype == bfd_link_hash_defined)
 611     {
 612       ASSERT (otype == bfd_link_hash_common);
 613       einfo ("%B: warning: definition of `%T' overriding common\n",
 614              nbfd, name);
 615       einfo ("%B: warning: common is here\n", obfd);
 616     }
 617   else if (otype == bfd_link_hash_defined)
 618     {
 619       ASSERT (ntype == bfd_link_hash_common);
 620       einfo ("%B: warning: common of `%T' overridden by definition\n",
 621              nbfd, name);
 622       einfo ("%B: warning: defined here\n", obfd);
 623     }
 624   else
 625     {
 626       ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
 627       if (osize > nsize)
 628         {
 629           einfo ("%B: warning: common of `%T' overridden by larger common\n",
 630                  nbfd, name);
 631           einfo ("%B: warning: larger common is here\n", obfd);
 632         }
 633       else if (nsize > osize)
 634         {
 635           einfo ("%B: warning: common of `%T' overriding smaller common\n",
 636                  nbfd, name);
 637           einfo ("%B: warning: smaller common is here\n", obfd);
 638         }
 639       else
 640         {
 641           einfo ("%B: warning: multiple common of `%T'\n", nbfd, name);
 642           einfo ("%B: warning: previous common is here\n", obfd);
 643         }
 644     }
 645
 646   return true;
 647 }
 648
 649 /* This is called when BFD has discovered a set element.  H is the
 650    entry in the linker hash table for the set.  SECTION and VALUE
 651    represent a value which should be added to the set.  */
 652
 653 /*ARGSUSED*/
 654 static boolean
 655 add_to_set (info, h, bitsize, abfd, section, value)
 656      struct bfd_link_info *info;
 657      struct bfd_link_hash_entry *h;
 658      unsigned int bitsize;
 659      bfd *abfd;
 660      asection *section;
 661      bfd_vma value;
 662 {
 663   ldctor_add_set_entry (h, bitsize, section, value);
 664   return true;
 665 }
 666
 667 /* This is called when BFD has discovered a constructor.  This is only
 668    called for some object file formats--those which do not handle
 669    constructors in some more clever fashion.  This is similar to
 670    adding an element to a set, but less general.  */
 671
 672 static boolean
 673 constructor_callback (info, constructor, bitsize, name, abfd, section, value)
 674      struct bfd_link_info *info;
 675      boolean constructor;
 676      unsigned int bitsize;
 677      const char *name;
 678      bfd *abfd;
 679      asection *section;
 680      bfd_vma value;
 681 {
 682   char *set_name;
 683   char *s;
 684   struct bfd_link_hash_entry *h;
 685
 686   if (! config.build_constructors)
 687     return true;
 688
 689   set_name = (char *) alloca (1 + sizeof "__CTOR_LIST__");
 690   s = set_name;
 691   if (bfd_get_symbol_leading_char (abfd) != '\0')
 692     *s++ = bfd_get_symbol_leading_char (abfd);
 693   if (constructor)
 694     strcpy (s, "__CTOR_LIST__");
 695   else
 696     strcpy (s, "__DTOR_LIST__");
 697
 698   if (write_map)
 699     info_msg ("Adding %s to constructor/destructor set %s\n", name, set_name);
 700
 701   h = bfd_link_hash_lookup (info->hash, set_name, true, true, true);
 702   if (h == (struct bfd_link_hash_entry *) NULL)
 703     einfo ("%P%F: bfd_link_hash_lookup failed: %E");
 704   if (h->type == bfd_link_hash_new)
 705     {
 706       h->type = bfd_link_hash_undefined;
 707       h->u.undef.abfd = abfd;
 708       /* We don't call bfd_link_add_undef to add this to the list of
 709          undefined symbols because we are going to define it
 710          ourselves.  */
 711     }
 712
 713   ldctor_add_set_entry (h, bitsize, section, value);
 714   return true;
 715 }
 716
 717 /* This is called when there is a reference to a warning symbol.  */
 718
 719 /*ARGSUSED*/
 720 static boolean
 721 warning_callback (info, warning)
 722      struct bfd_link_info *info;
 723      const char *warning;
 724 {
 725   einfo ("%P: %s\n", warning);
 726   return true;
 727 }
 728
 729 /* This is called when an undefined symbol is found.  */
 730
 731 /*ARGSUSED*/
 732 static boolean
 733 undefined_symbol (info, name, abfd, section, address)
 734      struct bfd_link_info *info;
 735      const char *name;
 736      bfd *abfd;
 737      asection *section;
 738      bfd_vma address;
 739 {
 740   static char *error_name;
 741   static unsigned int error_count;
 742
 743 #define MAX_ERRORS_IN_A_ROW 5
 744
 745   /* We never print more than a reasonable number of errors in a row
 746      for a single symbol.  */
 747   if (error_name != (char *) NULL
 748       && strcmp (name, error_name) == 0)
 749     ++error_count;
 750   else
 751     {
 752       error_count = 0;
 753       if (error_name != (char *) NULL)
 754         free (error_name);
 755       error_name = buystring (name);
 756     }
 757
 758   if (error_count < MAX_ERRORS_IN_A_ROW)
 759     einfo ("%X%C: undefined reference to `%T'\n",
 760            abfd, section, address, name);
 761   else if (error_count == MAX_ERRORS_IN_A_ROW)
 762     einfo ("%C: more undefined references to `%T' follow\n",
 763            abfd, section, address, name);
 764
 765   return true;
 766 }
 767
 768 /* This is called when a reloc overflows.  */
 769
 770 /*ARGSUSED*/
 771 static boolean
 772 reloc_overflow (info, name, reloc_name, addend, abfd, section, address)
 773      struct bfd_link_info *info;
 774      const char *name;
 775      const char *reloc_name;
 776      bfd_vma addend;
 777      bfd *abfd;
 778      asection *section;
 779      bfd_vma address;
 780 {
 781   einfo ("%X%C: relocation truncated to fit: %s %T", abfd, section,
 782          address, reloc_name, name);
 783   if (addend != 0)
 784     einfo ("+%v", addend);
 785   einfo ("\n");
 786   return true;
 787 }
 788
 789 /* This is called when a dangerous relocation is made.  */
 790
 791 /*ARGSUSED*/
 792 static boolean
 793 reloc_dangerous (info, message, abfd, section, address)
 794      struct bfd_link_info *info;
 795      const char *message;
 796      bfd *abfd;
 797      asection *section;
 798      bfd_vma address;
 799 {
 800   einfo ("%X%C: dangerous relocation: %s\n", abfd, section, address, message);
 801   return true;
 802 }
 803
 804 /* This is called when a reloc is being generated attached to a symbol
 805    that is not being output.  */
 806
 807 /*ARGSUSED*/
 808 static boolean
 809 unattached_reloc (info, name, abfd, section, address)
 810      struct bfd_link_info *info;
 811      const char *name;
 812      bfd *abfd;
 813      asection *section;
 814      bfd_vma address;
 815 {
 816   einfo ("%X%C: reloc refers to symbol `%T' which is not being output\n",
 817          abfd, section, address, name);
 818   return true;
 819 }
 820
 821 /* This is called when a symbol in notice_hash is found.  Symbols are
 822    put in notice_hash using the -y option.  */
 823
 824 /*ARGSUSED*/
 825 static boolean
 826 notice_ysym (info, name, abfd, section, value)
 827      struct bfd_link_info *info;
 828      const char *name;
 829      bfd *abfd;
 830      asection *section;
 831      bfd_vma value;
 832 {
 833   einfo ("%B: %s %s\n", abfd,
 834          section != &bfd_und_section ? "definition of" : "reference to",
 835          name);
 836   return true;
 837 }