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1 /* Main program of GNU linker.
2 Copyright 1991-2013 Free Software Foundation, Inc.
3 Written by Steve Chamberlain steve@cygnus.com
4
5 This file is part of the GNU Binutils.
6
7 This program 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 3 of the License, or
10 (at your option) any later version.
11
12 This program 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 this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
21
22 #include "sysdep.h"
23 #include "bfd.h"
24 #include "safe-ctype.h"
25 #include "libiberty.h"
26 #include "progress.h"
27 #include "bfdlink.h"
28 #include "filenames.h"
29
30 #include "ld.h"
31 #include "ldmain.h"
32 #include "ldmisc.h"
33 #include "ldwrite.h"
34 #include "ldexp.h"
35 #include "ldlang.h"
36 #include <ldgram.h>
37 #include "ldlex.h"
38 #include "ldfile.h"
39 #include "ldemul.h"
40 #include "ldctor.h"
41 #ifdef ENABLE_PLUGINS
42 #include "plugin.h"
43 #include "plugin-api.h"
44 #include "libbfd.h"
45 #endif /* ENABLE_PLUGINS */
46
47 /* Somewhere above, sys/stat.h got included. */
48 #if !defined(S_ISDIR) && defined(S_IFDIR)
49 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
50 #endif
51
52 #include <string.h>
53
54 #ifdef HAVE_SBRK
55 #if !HAVE_DECL_SBRK
56 extern void *sbrk ();
57 #endif
58 #endif
59
60 #ifndef TARGET_SYSTEM_ROOT
61 #define TARGET_SYSTEM_ROOT ""
62 #endif
63
64 /* EXPORTS */
65
66 FILE *saved_script_handle = NULL;
67 FILE *previous_script_handle = NULL;
68 bfd_boolean force_make_executable = FALSE;
69
70 char *default_target;
71 const char *output_filename = "a.out";
72
73 /* Name this program was invoked by. */
74 char *program_name;
75
76 /* The prefix for system library directories. */
77 const char *ld_sysroot;
78
79 /* The canonical representation of ld_sysroot. */
80 char * ld_canon_sysroot;
81 int ld_canon_sysroot_len;
82
83 /* Set by -G argument, for targets like MIPS ELF. */
84 int g_switch_value = 8;
85
86 /* Nonzero means print names of input files as processed. */
87 bfd_boolean trace_files;
88
89 /* Nonzero means report actions taken by the linker, and describe the linker script in use. */
90 bfd_boolean verbose;
91
92 /* Nonzero means version number was printed, so exit successfully
93 instead of complaining if no input files are given. */
94 bfd_boolean version_printed;
95
96 /* TRUE if we should demangle symbol names. */
97 bfd_boolean demangling;
98
99 args_type command_line;
100
101 ld_config_type config;
102
103 sort_type sort_section;
104
105 static const char *get_sysroot
106 (int, char **);
107 static char *get_emulation
108 (int, char **);
109 static bfd_boolean add_archive_element
110 (struct bfd_link_info *, bfd *, const char *, bfd **);
111 static bfd_boolean multiple_definition
112 (struct bfd_link_info *, struct bfd_link_hash_entry *,
113 bfd *, asection *, bfd_vma);
114 static bfd_boolean multiple_common
115 (struct bfd_link_info *, struct bfd_link_hash_entry *,
116 bfd *, enum bfd_link_hash_type, bfd_vma);
117 static bfd_boolean add_to_set
118 (struct bfd_link_info *, struct bfd_link_hash_entry *,
119 bfd_reloc_code_real_type, bfd *, asection *, bfd_vma);
120 static bfd_boolean constructor_callback
121 (struct bfd_link_info *, bfd_boolean, const char *, bfd *,
122 asection *, bfd_vma);
123 static bfd_boolean warning_callback
124 (struct bfd_link_info *, const char *, const char *, bfd *,
125 asection *, bfd_vma);
126 static void warning_find_reloc
127 (bfd *, asection *, void *);
128 static bfd_boolean undefined_symbol
129 (struct bfd_link_info *, const char *, bfd *, asection *, bfd_vma,
130 bfd_boolean);
131 static bfd_boolean reloc_overflow
132 (struct bfd_link_info *, struct bfd_link_hash_entry *, const char *,
133 const char *, bfd_vma, bfd *, asection *, bfd_vma);
134 static bfd_boolean reloc_dangerous
135 (struct bfd_link_info *, const char *, bfd *, asection *, bfd_vma);
136 static bfd_boolean unattached_reloc
137 (struct bfd_link_info *, const char *, bfd *, asection *, bfd_vma);
138 static bfd_boolean notice
139 (struct bfd_link_info *, struct bfd_link_hash_entry *,
140 bfd *, asection *, bfd_vma, flagword, const char *);
141
142 static struct bfd_link_callbacks link_callbacks =
143 {
144 add_archive_element,
145 multiple_definition,
146 multiple_common,
147 add_to_set,
148 constructor_callback,
149 warning_callback,
150 undefined_symbol,
151 reloc_overflow,
152 reloc_dangerous,
153 unattached_reloc,
154 notice,
155 einfo,
156 info_msg,
157 minfo,
158 ldlang_override_segment_assignment
159 };
160
161 static bfd_assert_handler_type default_bfd_assert_handler;
162
163 struct bfd_link_info link_info;
164 \f
165 static void
166 ld_cleanup (void)
167 {
168 bfd_cache_close_all ();
169 #ifdef ENABLE_PLUGINS
170 plugin_call_cleanup ();
171 #endif
172 if (output_filename && delete_output_file_on_failure)
173 unlink_if_ordinary (output_filename);
174 }
175
176 /* If there's a BFD assertion, we'll notice and exit with an error
177 unless otherwise instructed. */
178
179 static void
180 ld_bfd_assert_handler (const char *fmt, const char *bfdver,
181 const char *file, int line)
182 {
183 (*default_bfd_assert_handler) (fmt, bfdver, file, line);
184 config.make_executable = FALSE;
185 }
186
187 int
188 main (int argc, char **argv)
189 {
190 char *emulation;
191 long start_time = get_run_time ();
192 #ifdef HAVE_SBRK
193 char *start_sbrk = (char *) sbrk (0);
194 #endif
195
196 #if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
197 setlocale (LC_MESSAGES, "");
198 #endif
199 #if defined (HAVE_SETLOCALE)
200 setlocale (LC_CTYPE, "");
201 #endif
202 bindtextdomain (PACKAGE, LOCALEDIR);
203 textdomain (PACKAGE);
204
205 program_name = argv[0];
206 xmalloc_set_program_name (program_name);
207
208 START_PROGRESS (program_name, 0);
209
210 expandargv (&argc, &argv);
211
212 bfd_init ();
213
214 bfd_set_error_program_name (program_name);
215
216 /* We want to notice and fail on those nasty BFD assertions which are
217 likely to signal incorrect output being generated but otherwise may
218 leave no trace. */
219 default_bfd_assert_handler = bfd_set_assert_handler (ld_bfd_assert_handler);
220
221 xatexit (ld_cleanup);
222
223 /* Set up the sysroot directory. */
224 ld_sysroot = get_sysroot (argc, argv);
225 if (*ld_sysroot)
226 {
227 if (*TARGET_SYSTEM_ROOT == 0)
228 {
229 einfo ("%P%F: this linker was not configured to use sysroots\n");
230 ld_sysroot = "";
231 }
232 else
233 ld_canon_sysroot = lrealpath (ld_sysroot);
234 }
235 if (ld_canon_sysroot)
236 ld_canon_sysroot_len = strlen (ld_canon_sysroot);
237 else
238 ld_canon_sysroot_len = -1;
239
240 /* Set the default BFD target based on the configured target. Doing
241 this permits the linker to be configured for a particular target,
242 and linked against a shared BFD library which was configured for
243 a different target. The macro TARGET is defined by Makefile. */
244 if (! bfd_set_default_target (TARGET))
245 {
246 einfo (_("%X%P: can't set BFD default target to `%s': %E\n"), TARGET);
247 xexit (1);
248 }
249
250 #if YYDEBUG
251 {
252 extern int yydebug;
253 yydebug = 1;
254 }
255 #endif
256
257 config.build_constructors = TRUE;
258 config.rpath_separator = ':';
259 config.split_by_reloc = (unsigned) -1;
260 config.split_by_file = (bfd_size_type) -1;
261 config.make_executable = TRUE;
262 config.magic_demand_paged = TRUE;
263 config.text_read_only = TRUE;
264 link_info.disable_target_specific_optimizations = -1;
265
266 command_line.warn_mismatch = TRUE;
267 command_line.warn_search_mismatch = TRUE;
268 command_line.check_section_addresses = -1;
269
270 /* We initialize DEMANGLING based on the environment variable
271 COLLECT_NO_DEMANGLE. The gcc collect2 program will demangle the
272 output of the linker, unless COLLECT_NO_DEMANGLE is set in the
273 environment. Acting the same way here lets us provide the same
274 interface by default. */
275 demangling = getenv ("COLLECT_NO_DEMANGLE") == NULL;
276
277 link_info.allow_undefined_version = TRUE;
278 link_info.keep_memory = TRUE;
279 link_info.combreloc = TRUE;
280 link_info.strip_discarded = TRUE;
281 link_info.emit_hash = TRUE;
282 link_info.callbacks = &link_callbacks;
283 link_info.input_bfds_tail = &link_info.input_bfds;
284 /* SVR4 linkers seem to set DT_INIT and DT_FINI based on magic _init
285 and _fini symbols. We are compatible. */
286 link_info.init_function = "_init";
287 link_info.fini_function = "_fini";
288 link_info.relax_pass = 1;
289 link_info.pei386_auto_import = -1;
290 link_info.spare_dynamic_tags = 5;
291 link_info.path_separator = ':';
292
293 ldfile_add_arch ("");
294 emulation = get_emulation (argc, argv);
295 ldemul_choose_mode (emulation);
296 default_target = ldemul_choose_target (argc, argv);
297 config.maxpagesize = bfd_emul_get_maxpagesize (default_target);
298 config.commonpagesize = bfd_emul_get_commonpagesize (default_target);
299 lang_init ();
300 ldemul_before_parse ();
301 lang_has_input_file = FALSE;
302 parse_args (argc, argv);
303
304 if (config.hash_table_size != 0)
305 bfd_hash_set_default_size (config.hash_table_size);
306
307 #ifdef ENABLE_PLUGINS
308 /* Now all the plugin arguments have been gathered, we can load them. */
309 plugin_load_plugins ();
310 #endif /* ENABLE_PLUGINS */
311
312 ldemul_set_symbols ();
313
314 /* If we have not already opened and parsed a linker script,
315 try the default script from command line first. */
316 if (saved_script_handle == NULL
317 && command_line.default_script != NULL)
318 {
319 ldfile_open_command_file (command_line.default_script);
320 parser_input = input_script;
321 yyparse ();
322 }
323
324 /* If we have not already opened and parsed a linker script
325 read the emulation's appropriate default script. */
326 if (saved_script_handle == NULL)
327 {
328 int isfile;
329 char *s = ldemul_get_script (&isfile);
330
331 if (isfile)
332 ldfile_open_default_command_file (s);
333 else
334 {
335 lex_string = s;
336 lex_redirect (s, _("built in linker script"), 1);
337 }
338 parser_input = input_script;
339 yyparse ();
340 lex_string = NULL;
341 }
342
343 if (verbose)
344 {
345 if (saved_script_handle)
346 info_msg (_("using external linker script:"));
347 else
348 info_msg (_("using internal linker script:"));
349 info_msg ("\n==================================================\n");
350
351 if (saved_script_handle)
352 {
353 static const int ld_bufsz = 8193;
354 size_t n;
355 char *buf = (char *) xmalloc (ld_bufsz);
356
357 rewind (saved_script_handle);
358 while ((n = fread (buf, 1, ld_bufsz - 1, saved_script_handle)) > 0)
359 {
360 buf[n] = 0;
361 info_msg (buf);
362 }
363 rewind (saved_script_handle);
364 free (buf);
365 }
366 else
367 {
368 int isfile;
369
370 info_msg (ldemul_get_script (&isfile));
371 }
372
373 info_msg ("\n==================================================\n");
374 }
375
376 if (command_line.print_output_format)
377 info_msg ("%s\n", lang_get_output_target ());
378
379 lang_final ();
380
381 if (!lang_has_input_file)
382 {
383 if (version_printed || command_line.print_output_format)
384 xexit (0);
385 einfo (_("%P%F: no input files\n"));
386 }
387
388 if (trace_files)
389 info_msg (_("%P: mode %s\n"), emulation);
390
391 ldemul_after_parse ();
392
393 if (config.map_filename)
394 {
395 if (strcmp (config.map_filename, "-") == 0)
396 {
397 config.map_file = stdout;
398 }
399 else
400 {
401 config.map_file = fopen (config.map_filename, FOPEN_WT);
402 if (config.map_file == (FILE *) NULL)
403 {
404 bfd_set_error (bfd_error_system_call);
405 einfo (_("%P%F: cannot open map file %s: %E\n"),
406 config.map_filename);
407 }
408 }
409 }
410
411 lang_process ();
412
413 /* Print error messages for any missing symbols, for any warning
414 symbols, and possibly multiple definitions. */
415 if (link_info.relocatable)
416 link_info.output_bfd->flags &= ~EXEC_P;
417 else
418 link_info.output_bfd->flags |= EXEC_P;
419
420 ldwrite ();
421
422 if (config.map_file != NULL)
423 lang_map ();
424 if (command_line.cref)
425 output_cref (config.map_file != NULL ? config.map_file : stdout);
426 if (nocrossref_list != NULL)
427 check_nocrossrefs ();
428
429 lang_finish ();
430
431 /* Even if we're producing relocatable output, some non-fatal errors should
432 be reported in the exit status. (What non-fatal errors, if any, do we
433 want to ignore for relocatable output?) */
434 if (!config.make_executable && !force_make_executable)
435 {
436 if (trace_files)
437 einfo (_("%P: link errors found, deleting executable `%s'\n"),
438 output_filename);
439
440 /* The file will be removed by ld_cleanup. */
441 xexit (1);
442 }
443 else
444 {
445 if (! bfd_close (link_info.output_bfd))
446 einfo (_("%F%B: final close failed: %E\n"), link_info.output_bfd);
447
448 /* If the --force-exe-suffix is enabled, and we're making an
449 executable file and it doesn't end in .exe, copy it to one
450 which does. */
451 if (! link_info.relocatable && command_line.force_exe_suffix)
452 {
453 int len = strlen (output_filename);
454
455 if (len < 4
456 || (strcasecmp (output_filename + len - 4, ".exe") != 0
457 && strcasecmp (output_filename + len - 4, ".dll") != 0))
458 {
459 FILE *src;
460 FILE *dst;
461 const int bsize = 4096;
462 char *buf = (char *) xmalloc (bsize);
463 int l;
464 char *dst_name = (char *) xmalloc (len + 5);
465
466 strcpy (dst_name, output_filename);
467 strcat (dst_name, ".exe");
468 src = fopen (output_filename, FOPEN_RB);
469 dst = fopen (dst_name, FOPEN_WB);
470
471 if (!src)
472 einfo (_("%X%P: unable to open for source of copy `%s'\n"),
473 output_filename);
474 if (!dst)
475 einfo (_("%X%P: unable to open for destination of copy `%s'\n"),
476 dst_name);
477 while ((l = fread (buf, 1, bsize, src)) > 0)
478 {
479 int done = fwrite (buf, 1, l, dst);
480
481 if (done != l)
482 einfo (_("%P: Error writing file `%s'\n"), dst_name);
483 }
484
485 fclose (src);
486 if (fclose (dst) == EOF)
487 einfo (_("%P: Error closing file `%s'\n"), dst_name);
488 free (dst_name);
489 free (buf);
490 }
491 }
492 }
493
494 END_PROGRESS (program_name);
495
496 if (config.stats)
497 {
498 #ifdef HAVE_SBRK
499 char *lim = (char *) sbrk (0);
500 #endif
501 long run_time = get_run_time () - start_time;
502
503 fflush (stdout);
504 fprintf (stderr, _("%s: total time in link: %ld.%06ld\n"),
505 program_name, run_time / 1000000, run_time % 1000000);
506 #ifdef HAVE_SBRK
507 fprintf (stderr, _("%s: data size %ld\n"), program_name,
508 (long) (lim - start_sbrk));
509 #endif
510 fflush (stderr);
511 }
512
513 /* Prevent ld_cleanup from doing anything, after a successful link. */
514 output_filename = NULL;
515
516 xexit (0);
517 return 0;
518 }
519
520 /* If the configured sysroot is relocatable, try relocating it based on
521 default prefix FROM. Return the relocated directory if it exists,
522 otherwise return null. */
523
524 static char *
525 get_relative_sysroot (const char *from ATTRIBUTE_UNUSED)
526 {
527 #ifdef TARGET_SYSTEM_ROOT_RELOCATABLE
528 char *path;
529 struct stat s;
530
531 path = make_relative_prefix (program_name, from, TARGET_SYSTEM_ROOT);
532 if (path)
533 {
534 if (stat (path, &s) == 0 && S_ISDIR (s.st_mode))
535 return path;
536 free (path);
537 }
538 #endif
539 return 0;
540 }
541
542 /* Return the sysroot directory. Return "" if no sysroot is being used. */
543
544 static const char *
545 get_sysroot (int argc, char **argv)
546 {
547 int i;
548 const char *path;
549
550 for (i = 1; i < argc; i++)
551 if (CONST_STRNEQ (argv[i], "--sysroot="))
552 return argv[i] + strlen ("--sysroot=");
553
554 path = get_relative_sysroot (BINDIR);
555 if (path)
556 return path;
557
558 path = get_relative_sysroot (TOOLBINDIR);
559 if (path)
560 return path;
561
562 return TARGET_SYSTEM_ROOT;
563 }
564
565 /* We need to find any explicitly given emulation in order to initialize the
566 state that's needed by the lex&yacc argument parser (parse_args). */
567
568 static char *
569 get_emulation (int argc, char **argv)
570 {
571 char *emulation;
572 int i;
573
574 emulation = getenv (EMULATION_ENVIRON);
575 if (emulation == NULL)
576 emulation = DEFAULT_EMULATION;
577
578 for (i = 1; i < argc; i++)
579 {
580 if (CONST_STRNEQ (argv[i], "-m"))
581 {
582 if (argv[i][2] == '\0')
583 {
584 /* -m EMUL */
585 if (i < argc - 1)
586 {
587 emulation = argv[i + 1];
588 i++;
589 }
590 else
591 einfo (_("%P%F: missing argument to -m\n"));
592 }
593 else if (strcmp (argv[i], "-mips1") == 0
594 || strcmp (argv[i], "-mips2") == 0
595 || strcmp (argv[i], "-mips3") == 0
596 || strcmp (argv[i], "-mips4") == 0
597 || strcmp (argv[i], "-mips5") == 0
598 || strcmp (argv[i], "-mips32") == 0
599 || strcmp (argv[i], "-mips32r2") == 0
600 || strcmp (argv[i], "-mips64") == 0
601 || strcmp (argv[i], "-mips64r2") == 0)
602 {
603 /* FIXME: The arguments -mips1, -mips2, -mips3, etc. are
604 passed to the linker by some MIPS compilers. They
605 generally tell the linker to use a slightly different
606 library path. Perhaps someday these should be
607 implemented as emulations; until then, we just ignore
608 the arguments and hope that nobody ever creates
609 emulations named ips1, ips2 or ips3. */
610 }
611 else if (strcmp (argv[i], "-m486") == 0)
612 {
613 /* FIXME: The argument -m486 is passed to the linker on
614 some Linux systems. Hope that nobody creates an
615 emulation named 486. */
616 }
617 else
618 {
619 /* -mEMUL */
620 emulation = &argv[i][2];
621 }
622 }
623 }
624
625 return emulation;
626 }
627
628 void
629 add_ysym (const char *name)
630 {
631 if (link_info.notice_hash == NULL)
632 {
633 link_info.notice_hash =
634 (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table));
635 if (!bfd_hash_table_init_n (link_info.notice_hash,
636 bfd_hash_newfunc,
637 sizeof (struct bfd_hash_entry),
638 61))
639 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
640 }
641
642 if (bfd_hash_lookup (link_info.notice_hash, name, TRUE, TRUE) == NULL)
643 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
644 }
645
646 void
647 add_ignoresym (struct bfd_link_info *info, const char *name)
648 {
649 if (info->ignore_hash == NULL)
650 {
651 info->ignore_hash = xmalloc (sizeof (struct bfd_hash_table));
652 if (! bfd_hash_table_init_n (info->ignore_hash,
653 bfd_hash_newfunc,
654 sizeof (struct bfd_hash_entry),
655 61))
656 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
657 }
658
659 if (bfd_hash_lookup (info->ignore_hash, name, TRUE, TRUE) == NULL)
660 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
661 }
662
663 /* Record a symbol to be wrapped, from the --wrap option. */
664
665 void
666 add_wrap (const char *name)
667 {
668 if (link_info.wrap_hash == NULL)
669 {
670 link_info.wrap_hash =
671 (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table));
672 if (!bfd_hash_table_init_n (link_info.wrap_hash,
673 bfd_hash_newfunc,
674 sizeof (struct bfd_hash_entry),
675 61))
676 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
677 }
678
679 if (bfd_hash_lookup (link_info.wrap_hash, name, TRUE, TRUE) == NULL)
680 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
681 }
682
683 /* Handle the -retain-symbols-file option. */
684
685 void
686 add_keepsyms_file (const char *filename)
687 {
688 FILE *file;
689 char *buf;
690 size_t bufsize;
691 int c;
692
693 if (link_info.strip == strip_some)
694 einfo (_("%X%P: error: duplicate retain-symbols-file\n"));
695
696 file = fopen (filename, "r");
697 if (file == NULL)
698 {
699 bfd_set_error (bfd_error_system_call);
700 einfo ("%X%P: %s: %E\n", filename);
701 return;
702 }
703
704 link_info.keep_hash = (struct bfd_hash_table *)
705 xmalloc (sizeof (struct bfd_hash_table));
706 if (!bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc,
707 sizeof (struct bfd_hash_entry)))
708 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
709
710 bufsize = 100;
711 buf = (char *) xmalloc (bufsize);
712
713 c = getc (file);
714 while (c != EOF)
715 {
716 while (ISSPACE (c))
717 c = getc (file);
718
719 if (c != EOF)
720 {
721 size_t len = 0;
722
723 while (! ISSPACE (c) && c != EOF)
724 {
725 buf[len] = c;
726 ++len;
727 if (len >= bufsize)
728 {
729 bufsize *= 2;
730 buf = (char *) xrealloc (buf, bufsize);
731 }
732 c = getc (file);
733 }
734
735 buf[len] = '\0';
736
737 if (bfd_hash_lookup (link_info.keep_hash, buf, TRUE, TRUE) == NULL)
738 einfo (_("%P%F: bfd_hash_lookup for insertion failed: %E\n"));
739 }
740 }
741
742 if (link_info.strip != strip_none)
743 einfo (_("%P: `-retain-symbols-file' overrides `-s' and `-S'\n"));
744
745 free (buf);
746 link_info.strip = strip_some;
747 fclose (file);
748 }
749 \f
750 /* Callbacks from the BFD linker routines. */
751
752 /* This is called when BFD has decided to include an archive member in
753 a link. */
754
755 static bfd_boolean
756 add_archive_element (struct bfd_link_info *info,
757 bfd *abfd,
758 const char *name,
759 bfd **subsbfd ATTRIBUTE_UNUSED)
760 {
761 lang_input_statement_type *input;
762 lang_input_statement_type orig_input;
763
764 input = (lang_input_statement_type *)
765 xcalloc (1, sizeof (lang_input_statement_type));
766 input->filename = abfd->filename;
767 input->local_sym_name = abfd->filename;
768 input->the_bfd = abfd;
769
770 /* Save the original data for trace files/tries below, as plugins
771 (if enabled) may possibly alter it to point to a replacement
772 BFD, but we still want to output the original BFD filename. */
773 orig_input = *input;
774 #ifdef ENABLE_PLUGINS
775 if (plugin_active_plugins_p () && !no_more_claiming)
776 {
777 /* We must offer this archive member to the plugins to claim. */
778 const char *filename = (bfd_my_archive (abfd) != NULL
779 ? bfd_my_archive (abfd)->filename : abfd->filename);
780 int fd = open (filename, O_RDONLY | O_BINARY);
781 if (fd >= 0)
782 {
783 struct ld_plugin_input_file file;
784
785 /* Offset and filesize must refer to the individual archive
786 member, not the whole file, and must exclude the header.
787 Fortunately for us, that is how the data is stored in the
788 origin field of the bfd and in the arelt_data. */
789 file.name = filename;
790 file.offset = abfd->origin;
791 file.filesize = arelt_size (abfd);
792 file.fd = fd;
793 plugin_maybe_claim (&file, input);
794 if (input->flags.claimed)
795 {
796 input->flags.claim_archive = TRUE;
797 *subsbfd = input->the_bfd;
798 }
799 }
800 }
801 #endif /* ENABLE_PLUGINS */
802
803 ldlang_add_file (input);
804
805 if (config.map_file != NULL)
806 {
807 static bfd_boolean header_printed;
808 struct bfd_link_hash_entry *h;
809 bfd *from;
810 int len;
811
812 h = bfd_link_hash_lookup (info->hash, name, FALSE, FALSE, TRUE);
813
814 if (h == NULL)
815 from = NULL;
816 else
817 {
818 switch (h->type)
819 {
820 default:
821 from = NULL;
822 break;
823
824 case bfd_link_hash_defined:
825 case bfd_link_hash_defweak:
826 from = h->u.def.section->owner;
827 break;
828
829 case bfd_link_hash_undefined:
830 case bfd_link_hash_undefweak:
831 from = h->u.undef.abfd;
832 break;
833
834 case bfd_link_hash_common:
835 from = h->u.c.p->section->owner;
836 break;
837 }
838 }
839
840 if (! header_printed)
841 {
842 char buf[100];
843
844 sprintf (buf, _("Archive member included "
845 "to satisfy reference by file (symbol)\n\n"));
846 minfo ("%s", buf);
847 header_printed = TRUE;
848 }
849
850 if (bfd_my_archive (abfd) == NULL)
851 {
852 minfo ("%s", bfd_get_filename (abfd));
853 len = strlen (bfd_get_filename (abfd));
854 }
855 else
856 {
857 minfo ("%s(%s)", bfd_get_filename (bfd_my_archive (abfd)),
858 bfd_get_filename (abfd));
859 len = (strlen (bfd_get_filename (bfd_my_archive (abfd)))
860 + strlen (bfd_get_filename (abfd))
861 + 2);
862 }
863
864 if (len >= 29)
865 {
866 print_nl ();
867 len = 0;
868 }
869 while (len < 30)
870 {
871 print_space ();
872 ++len;
873 }
874
875 if (from != NULL)
876 minfo ("%B ", from);
877 if (h != NULL)
878 minfo ("(%T)\n", h->root.string);
879 else
880 minfo ("(%s)\n", name);
881 }
882
883 if (trace_files || verbose)
884 info_msg ("%I\n", &orig_input);
885 return TRUE;
886 }
887
888 /* This is called when BFD has discovered a symbol which is defined
889 multiple times. */
890
891 static bfd_boolean
892 multiple_definition (struct bfd_link_info *info,
893 struct bfd_link_hash_entry *h,
894 bfd *nbfd,
895 asection *nsec,
896 bfd_vma nval)
897 {
898 const char *name;
899 bfd *obfd;
900 asection *osec;
901 bfd_vma oval;
902
903 if (info->allow_multiple_definition)
904 return TRUE;
905
906 switch (h->type)
907 {
908 case bfd_link_hash_defined:
909 osec = h->u.def.section;
910 oval = h->u.def.value;
911 obfd = h->u.def.section->owner;
912 break;
913 case bfd_link_hash_indirect:
914 osec = bfd_ind_section_ptr;
915 oval = 0;
916 obfd = NULL;
917 break;
918 default:
919 abort ();
920 }
921
922 /* Ignore a redefinition of an absolute symbol to the
923 same value; it's harmless. */
924 if (h->type == bfd_link_hash_defined
925 && bfd_is_abs_section (osec)
926 && bfd_is_abs_section (nsec)
927 && nval == oval)
928 return TRUE;
929
930 /* If either section has the output_section field set to
931 bfd_abs_section_ptr, it means that the section is being
932 discarded, and this is not really a multiple definition at all.
933 FIXME: It would be cleaner to somehow ignore symbols defined in
934 sections which are being discarded. */
935 if ((osec->output_section != NULL
936 && ! bfd_is_abs_section (osec)
937 && bfd_is_abs_section (osec->output_section))
938 || (nsec->output_section != NULL
939 && ! bfd_is_abs_section (nsec)
940 && bfd_is_abs_section (nsec->output_section)))
941 return TRUE;
942
943 name = h->root.string;
944 if (nbfd == NULL)
945 {
946 nbfd = obfd;
947 nsec = osec;
948 nval = oval;
949 obfd = NULL;
950 }
951 einfo (_("%X%C: multiple definition of `%T'\n"),
952 nbfd, nsec, nval, name);
953 if (obfd != NULL)
954 einfo (_("%D: first defined here\n"), obfd, osec, oval);
955
956 if (RELAXATION_ENABLED_BY_USER)
957 {
958 einfo (_("%P: Disabling relaxation: it will not work with multiple definitions\n"));
959 DISABLE_RELAXATION;
960 }
961
962 return TRUE;
963 }
964
965 /* This is called when there is a definition of a common symbol, or
966 when a common symbol is found for a symbol that is already defined,
967 or when two common symbols are found. We only do something if
968 -warn-common was used. */
969
970 static bfd_boolean
971 multiple_common (struct bfd_link_info *info ATTRIBUTE_UNUSED,
972 struct bfd_link_hash_entry *h,
973 bfd *nbfd,
974 enum bfd_link_hash_type ntype,
975 bfd_vma nsize)
976 {
977 const char *name;
978 bfd *obfd;
979 enum bfd_link_hash_type otype;
980 bfd_vma osize;
981
982 if (!config.warn_common)
983 return TRUE;
984
985 name = h->root.string;
986 otype = h->type;
987 if (otype == bfd_link_hash_common)
988 {
989 obfd = h->u.c.p->section->owner;
990 osize = h->u.c.size;
991 }
992 else if (otype == bfd_link_hash_defined
993 || otype == bfd_link_hash_defweak)
994 {
995 obfd = h->u.def.section->owner;
996 osize = 0;
997 }
998 else
999 {
1000 /* FIXME: It would nice if we could report the BFD which defined
1001 an indirect symbol, but we don't have anywhere to store the
1002 information. */
1003 obfd = NULL;
1004 osize = 0;
1005 }
1006
1007 if (ntype == bfd_link_hash_defined
1008 || ntype == bfd_link_hash_defweak
1009 || ntype == bfd_link_hash_indirect)
1010 {
1011 ASSERT (otype == bfd_link_hash_common);
1012 einfo (_("%B: warning: definition of `%T' overriding common\n"),
1013 nbfd, name);
1014 if (obfd != NULL)
1015 einfo (_("%B: warning: common is here\n"), obfd);
1016 }
1017 else if (otype == bfd_link_hash_defined
1018 || otype == bfd_link_hash_defweak
1019 || otype == bfd_link_hash_indirect)
1020 {
1021 ASSERT (ntype == bfd_link_hash_common);
1022 einfo (_("%B: warning: common of `%T' overridden by definition\n"),
1023 nbfd, name);
1024 if (obfd != NULL)
1025 einfo (_("%B: warning: defined here\n"), obfd);
1026 }
1027 else
1028 {
1029 ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
1030 if (osize > nsize)
1031 {
1032 einfo (_("%B: warning: common of `%T' overridden by larger common\n"),
1033 nbfd, name);
1034 if (obfd != NULL)
1035 einfo (_("%B: warning: larger common is here\n"), obfd);
1036 }
1037 else if (nsize > osize)
1038 {
1039 einfo (_("%B: warning: common of `%T' overriding smaller common\n"),
1040 nbfd, name);
1041 if (obfd != NULL)
1042 einfo (_("%B: warning: smaller common is here\n"), obfd);
1043 }
1044 else
1045 {
1046 einfo (_("%B: warning: multiple common of `%T'\n"), nbfd, name);
1047 if (obfd != NULL)
1048 einfo (_("%B: warning: previous common is here\n"), obfd);
1049 }
1050 }
1051
1052 return TRUE;
1053 }
1054
1055 /* This is called when BFD has discovered a set element. H is the
1056 entry in the linker hash table for the set. SECTION and VALUE
1057 represent a value which should be added to the set. */
1058
1059 static bfd_boolean
1060 add_to_set (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1061 struct bfd_link_hash_entry *h,
1062 bfd_reloc_code_real_type reloc,
1063 bfd *abfd,
1064 asection *section,
1065 bfd_vma value)
1066 {
1067 if (config.warn_constructors)
1068 einfo (_("%P: warning: global constructor %s used\n"),
1069 h->root.string);
1070
1071 if (! config.build_constructors)
1072 return TRUE;
1073
1074 ldctor_add_set_entry (h, reloc, NULL, section, value);
1075
1076 if (h->type == bfd_link_hash_new)
1077 {
1078 h->type = bfd_link_hash_undefined;
1079 h->u.undef.abfd = abfd;
1080 /* We don't call bfd_link_add_undef to add this to the list of
1081 undefined symbols because we are going to define it
1082 ourselves. */
1083 }
1084
1085 return TRUE;
1086 }
1087
1088 /* This is called when BFD has discovered a constructor. This is only
1089 called for some object file formats--those which do not handle
1090 constructors in some more clever fashion. This is similar to
1091 adding an element to a set, but less general. */
1092
1093 static bfd_boolean
1094 constructor_callback (struct bfd_link_info *info,
1095 bfd_boolean constructor,
1096 const char *name,
1097 bfd *abfd,
1098 asection *section,
1099 bfd_vma value)
1100 {
1101 char *s;
1102 struct bfd_link_hash_entry *h;
1103 char set_name[1 + sizeof "__CTOR_LIST__"];
1104
1105 if (config.warn_constructors)
1106 einfo (_("%P: warning: global constructor %s used\n"), name);
1107
1108 if (! config.build_constructors)
1109 return TRUE;
1110
1111 /* Ensure that BFD_RELOC_CTOR exists now, so that we can give a
1112 useful error message. */
1113 if (bfd_reloc_type_lookup (info->output_bfd, BFD_RELOC_CTOR) == NULL
1114 && (info->relocatable
1115 || bfd_reloc_type_lookup (abfd, BFD_RELOC_CTOR) == NULL))
1116 einfo (_("%P%F: BFD backend error: BFD_RELOC_CTOR unsupported\n"));
1117
1118 s = set_name;
1119 if (bfd_get_symbol_leading_char (abfd) != '\0')
1120 *s++ = bfd_get_symbol_leading_char (abfd);
1121 if (constructor)
1122 strcpy (s, "__CTOR_LIST__");
1123 else
1124 strcpy (s, "__DTOR_LIST__");
1125
1126 h = bfd_link_hash_lookup (info->hash, set_name, TRUE, TRUE, TRUE);
1127 if (h == (struct bfd_link_hash_entry *) NULL)
1128 einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
1129 if (h->type == bfd_link_hash_new)
1130 {
1131 h->type = bfd_link_hash_undefined;
1132 h->u.undef.abfd = abfd;
1133 /* We don't call bfd_link_add_undef to add this to the list of
1134 undefined symbols because we are going to define it
1135 ourselves. */
1136 }
1137
1138 ldctor_add_set_entry (h, BFD_RELOC_CTOR, name, section, value);
1139 return TRUE;
1140 }
1141
1142 /* A structure used by warning_callback to pass information through
1143 bfd_map_over_sections. */
1144
1145 struct warning_callback_info
1146 {
1147 bfd_boolean found;
1148 const char *warning;
1149 const char *symbol;
1150 asymbol **asymbols;
1151 };
1152
1153 /* This is called when there is a reference to a warning symbol. */
1154
1155 static bfd_boolean
1156 warning_callback (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1157 const char *warning,
1158 const char *symbol,
1159 bfd *abfd,
1160 asection *section,
1161 bfd_vma address)
1162 {
1163 /* This is a hack to support warn_multiple_gp. FIXME: This should
1164 have a cleaner interface, but what? */
1165 if (! config.warn_multiple_gp
1166 && strcmp (warning, "using multiple gp values") == 0)
1167 return TRUE;
1168
1169 if (section != NULL)
1170 einfo ("%C: %s%s\n", abfd, section, address, _("warning: "), warning);
1171 else if (abfd == NULL)
1172 einfo ("%P: %s%s\n", _("warning: "), warning);
1173 else if (symbol == NULL)
1174 einfo ("%B: %s%s\n", abfd, _("warning: "), warning);
1175 else
1176 {
1177 struct warning_callback_info cinfo;
1178
1179 /* Look through the relocs to see if we can find a plausible
1180 address. */
1181
1182 if (!bfd_generic_link_read_symbols (abfd))
1183 einfo (_("%B%F: could not read symbols: %E\n"), abfd);
1184
1185 cinfo.found = FALSE;
1186 cinfo.warning = warning;
1187 cinfo.symbol = symbol;
1188 cinfo.asymbols = bfd_get_outsymbols (abfd);
1189 bfd_map_over_sections (abfd, warning_find_reloc, &cinfo);
1190
1191 if (! cinfo.found)
1192 einfo ("%B: %s%s\n", abfd, _("warning: "), warning);
1193 }
1194
1195 return TRUE;
1196 }
1197
1198 /* This is called by warning_callback for each section. It checks the
1199 relocs of the section to see if it can find a reference to the
1200 symbol which triggered the warning. If it can, it uses the reloc
1201 to give an error message with a file and line number. */
1202
1203 static void
1204 warning_find_reloc (bfd *abfd, asection *sec, void *iarg)
1205 {
1206 struct warning_callback_info *info = (struct warning_callback_info *) iarg;
1207 long relsize;
1208 arelent **relpp;
1209 long relcount;
1210 arelent **p, **pend;
1211
1212 if (info->found)
1213 return;
1214
1215 relsize = bfd_get_reloc_upper_bound (abfd, sec);
1216 if (relsize < 0)
1217 einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1218 if (relsize == 0)
1219 return;
1220
1221 relpp = (arelent **) xmalloc (relsize);
1222 relcount = bfd_canonicalize_reloc (abfd, sec, relpp, info->asymbols);
1223 if (relcount < 0)
1224 einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1225
1226 p = relpp;
1227 pend = p + relcount;
1228 for (; p < pend && *p != NULL; p++)
1229 {
1230 arelent *q = *p;
1231
1232 if (q->sym_ptr_ptr != NULL
1233 && *q->sym_ptr_ptr != NULL
1234 && strcmp (bfd_asymbol_name (*q->sym_ptr_ptr), info->symbol) == 0)
1235 {
1236 /* We found a reloc for the symbol we are looking for. */
1237 einfo ("%C: %s%s\n", abfd, sec, q->address, _("warning: "),
1238 info->warning);
1239 info->found = TRUE;
1240 break;
1241 }
1242 }
1243
1244 free (relpp);
1245 }
1246
1247 /* This is called when an undefined symbol is found. */
1248
1249 static bfd_boolean
1250 undefined_symbol (struct bfd_link_info *info,
1251 const char *name,
1252 bfd *abfd,
1253 asection *section,
1254 bfd_vma address,
1255 bfd_boolean error)
1256 {
1257 static char *error_name;
1258 static unsigned int error_count;
1259
1260 #define MAX_ERRORS_IN_A_ROW 5
1261
1262 if (info->ignore_hash != NULL
1263 && bfd_hash_lookup (info->ignore_hash, name, FALSE, FALSE) != NULL)
1264 return TRUE;
1265
1266 if (config.warn_once)
1267 {
1268 /* Only warn once about a particular undefined symbol. */
1269 add_ignoresym (info, name);
1270 }
1271
1272 /* We never print more than a reasonable number of errors in a row
1273 for a single symbol. */
1274 if (error_name != NULL
1275 && strcmp (name, error_name) == 0)
1276 ++error_count;
1277 else
1278 {
1279 error_count = 0;
1280 if (error_name != NULL)
1281 free (error_name);
1282 error_name = xstrdup (name);
1283 }
1284
1285 if (section != NULL)
1286 {
1287 if (error_count < MAX_ERRORS_IN_A_ROW)
1288 {
1289 if (error)
1290 einfo (_("%X%C: undefined reference to `%T'\n"),
1291 abfd, section, address, name);
1292 else
1293 einfo (_("%C: warning: undefined reference to `%T'\n"),
1294 abfd, section, address, name);
1295 }
1296 else if (error_count == MAX_ERRORS_IN_A_ROW)
1297 {
1298 if (error)
1299 einfo (_("%X%D: more undefined references to `%T' follow\n"),
1300 abfd, section, address, name);
1301 else
1302 einfo (_("%D: warning: more undefined references to `%T' follow\n"),
1303 abfd, section, address, name);
1304 }
1305 else if (error)
1306 einfo ("%X");
1307 }
1308 else
1309 {
1310 if (error_count < MAX_ERRORS_IN_A_ROW)
1311 {
1312 if (error)
1313 einfo (_("%X%B: undefined reference to `%T'\n"),
1314 abfd, name);
1315 else
1316 einfo (_("%B: warning: undefined reference to `%T'\n"),
1317 abfd, name);
1318 }
1319 else if (error_count == MAX_ERRORS_IN_A_ROW)
1320 {
1321 if (error)
1322 einfo (_("%X%B: more undefined references to `%T' follow\n"),
1323 abfd, name);
1324 else
1325 einfo (_("%B: warning: more undefined references to `%T' follow\n"),
1326 abfd, name);
1327 }
1328 else if (error)
1329 einfo ("%X");
1330 }
1331
1332 return TRUE;
1333 }
1334
1335 /* Counter to limit the number of relocation overflow error messages
1336 to print. Errors are printed as it is decremented. When it's
1337 called and the counter is zero, a final message is printed
1338 indicating more relocations were omitted. When it gets to -1, no
1339 such errors are printed. If it's initially set to a value less
1340 than -1, all such errors will be printed (--verbose does this). */
1341
1342 int overflow_cutoff_limit = 10;
1343
1344 /* This is called when a reloc overflows. */
1345
1346 static bfd_boolean
1347 reloc_overflow (struct bfd_link_info *info,
1348 struct bfd_link_hash_entry *entry,
1349 const char *name,
1350 const char *reloc_name,
1351 bfd_vma addend,
1352 bfd *abfd,
1353 asection *section,
1354 bfd_vma address)
1355 {
1356 if (overflow_cutoff_limit == -1)
1357 return TRUE;
1358
1359 einfo ("%X%H:", abfd, section, address);
1360
1361 if (overflow_cutoff_limit >= 0
1362 && overflow_cutoff_limit-- == 0)
1363 {
1364 einfo (_(" additional relocation overflows omitted from the output\n"));
1365 return TRUE;
1366 }
1367
1368 if (entry)
1369 {
1370 while (entry->type == bfd_link_hash_indirect
1371 || entry->type == bfd_link_hash_warning)
1372 entry = entry->u.i.link;
1373 switch (entry->type)
1374 {
1375 case bfd_link_hash_undefined:
1376 case bfd_link_hash_undefweak:
1377 einfo (_(" relocation truncated to fit: %s against undefined symbol `%T'"),
1378 reloc_name, entry->root.string);
1379 break;
1380 case bfd_link_hash_defined:
1381 case bfd_link_hash_defweak:
1382 einfo (_(" relocation truncated to fit: %s against symbol `%T' defined in %A section in %B"),
1383 reloc_name, entry->root.string,
1384 entry->u.def.section,
1385 entry->u.def.section == bfd_abs_section_ptr
1386 ? info->output_bfd : entry->u.def.section->owner);
1387 break;
1388 default:
1389 abort ();
1390 break;
1391 }
1392 }
1393 else
1394 einfo (_(" relocation truncated to fit: %s against `%T'"),
1395 reloc_name, name);
1396 if (addend != 0)
1397 einfo ("+%v", addend);
1398 einfo ("\n");
1399 return TRUE;
1400 }
1401
1402 /* This is called when a dangerous relocation is made. */
1403
1404 static bfd_boolean
1405 reloc_dangerous (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1406 const char *message,
1407 bfd *abfd,
1408 asection *section,
1409 bfd_vma address)
1410 {
1411 einfo (_("%X%H: dangerous relocation: %s\n"),
1412 abfd, section, address, message);
1413 return TRUE;
1414 }
1415
1416 /* This is called when a reloc is being generated attached to a symbol
1417 that is not being output. */
1418
1419 static bfd_boolean
1420 unattached_reloc (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1421 const char *name,
1422 bfd *abfd,
1423 asection *section,
1424 bfd_vma address)
1425 {
1426 einfo (_("%X%H: reloc refers to symbol `%T' which is not being output\n"),
1427 abfd, section, address, name);
1428 return TRUE;
1429 }
1430
1431 /* This is called if link_info.notice_all is set, or when a symbol in
1432 link_info.notice_hash is found. Symbols are put in notice_hash
1433 using the -y option, while notice_all is set if the --cref option
1434 has been supplied, or if there are any NOCROSSREFS sections in the
1435 linker script; and if plugins are active, since they need to monitor
1436 all references from non-IR files. */
1437
1438 static bfd_boolean
1439 notice (struct bfd_link_info *info,
1440 struct bfd_link_hash_entry *h,
1441 bfd *abfd,
1442 asection *section,
1443 bfd_vma value,
1444 flagword flags ATTRIBUTE_UNUSED,
1445 const char *string ATTRIBUTE_UNUSED)
1446 {
1447 const char *name;
1448
1449 if (h == NULL)
1450 {
1451 if (command_line.cref || nocrossref_list != NULL)
1452 return handle_asneeded_cref (abfd, (enum notice_asneeded_action) value);
1453 return TRUE;
1454 }
1455
1456 name = h->root.string;
1457 if (info->notice_hash != NULL
1458 && bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL)
1459 {
1460 if (bfd_is_und_section (section))
1461 einfo ("%B: reference to %s\n", abfd, name);
1462 else
1463 einfo ("%B: definition of %s\n", abfd, name);
1464 }
1465
1466 if (command_line.cref || nocrossref_list != NULL)
1467 add_cref (name, abfd, section, value);
1468
1469 return TRUE;
1470 }