Fix fallout from splitting ldbuildid.[ch] off elf32.em.
[deliverable/binutils-gdb.git] / ld / ldmain.c
1 /* Main program of GNU linker.
2 Copyright (C) 1991-2014 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 the only command line argument has been -v or --version or --verbose
382 then ignore any input files provided by linker scripts and exit now.
383 We do not want to create an output file when the linker is just invoked
384 to provide version information. */
385 if (argc == 2 && version_printed)
386 xexit (0);
387
388 if (!lang_has_input_file)
389 {
390 if (version_printed || command_line.print_output_format)
391 xexit (0);
392 einfo (_("%P%F: no input files\n"));
393 }
394
395 if (trace_files)
396 info_msg (_("%P: mode %s\n"), emulation);
397
398 ldemul_after_parse ();
399
400 if (config.map_filename)
401 {
402 if (strcmp (config.map_filename, "-") == 0)
403 {
404 config.map_file = stdout;
405 }
406 else
407 {
408 config.map_file = fopen (config.map_filename, FOPEN_WT);
409 if (config.map_file == (FILE *) NULL)
410 {
411 bfd_set_error (bfd_error_system_call);
412 einfo (_("%P%F: cannot open map file %s: %E\n"),
413 config.map_filename);
414 }
415 }
416 }
417
418 lang_process ();
419
420 /* Print error messages for any missing symbols, for any warning
421 symbols, and possibly multiple definitions. */
422 if (link_info.relocatable)
423 link_info.output_bfd->flags &= ~EXEC_P;
424 else
425 link_info.output_bfd->flags |= EXEC_P;
426
427 ldwrite ();
428
429 if (config.map_file != NULL)
430 lang_map ();
431 if (command_line.cref)
432 output_cref (config.map_file != NULL ? config.map_file : stdout);
433 if (nocrossref_list != NULL)
434 check_nocrossrefs ();
435
436 lang_finish ();
437
438 /* Even if we're producing relocatable output, some non-fatal errors should
439 be reported in the exit status. (What non-fatal errors, if any, do we
440 want to ignore for relocatable output?) */
441 if (!config.make_executable && !force_make_executable)
442 {
443 if (trace_files)
444 einfo (_("%P: link errors found, deleting executable `%s'\n"),
445 output_filename);
446
447 /* The file will be removed by ld_cleanup. */
448 xexit (1);
449 }
450 else
451 {
452 if (! bfd_close (link_info.output_bfd))
453 einfo (_("%F%B: final close failed: %E\n"), link_info.output_bfd);
454
455 /* If the --force-exe-suffix is enabled, and we're making an
456 executable file and it doesn't end in .exe, copy it to one
457 which does. */
458 if (! link_info.relocatable && command_line.force_exe_suffix)
459 {
460 int len = strlen (output_filename);
461
462 if (len < 4
463 || (strcasecmp (output_filename + len - 4, ".exe") != 0
464 && strcasecmp (output_filename + len - 4, ".dll") != 0))
465 {
466 FILE *src;
467 FILE *dst;
468 const int bsize = 4096;
469 char *buf = (char *) xmalloc (bsize);
470 int l;
471 char *dst_name = (char *) xmalloc (len + 5);
472
473 strcpy (dst_name, output_filename);
474 strcat (dst_name, ".exe");
475 src = fopen (output_filename, FOPEN_RB);
476 dst = fopen (dst_name, FOPEN_WB);
477
478 if (!src)
479 einfo (_("%X%P: unable to open for source of copy `%s'\n"),
480 output_filename);
481 if (!dst)
482 einfo (_("%X%P: unable to open for destination of copy `%s'\n"),
483 dst_name);
484 while ((l = fread (buf, 1, bsize, src)) > 0)
485 {
486 int done = fwrite (buf, 1, l, dst);
487
488 if (done != l)
489 einfo (_("%P: Error writing file `%s'\n"), dst_name);
490 }
491
492 fclose (src);
493 if (fclose (dst) == EOF)
494 einfo (_("%P: Error closing file `%s'\n"), dst_name);
495 free (dst_name);
496 free (buf);
497 }
498 }
499 }
500
501 END_PROGRESS (program_name);
502
503 if (config.stats)
504 {
505 #ifdef HAVE_SBRK
506 char *lim = (char *) sbrk (0);
507 #endif
508 long run_time = get_run_time () - start_time;
509
510 fflush (stdout);
511 fprintf (stderr, _("%s: total time in link: %ld.%06ld\n"),
512 program_name, run_time / 1000000, run_time % 1000000);
513 #ifdef HAVE_SBRK
514 fprintf (stderr, _("%s: data size %ld\n"), program_name,
515 (long) (lim - start_sbrk));
516 #endif
517 fflush (stderr);
518 }
519
520 /* Prevent ld_cleanup from doing anything, after a successful link. */
521 output_filename = NULL;
522
523 xexit (0);
524 return 0;
525 }
526
527 /* If the configured sysroot is relocatable, try relocating it based on
528 default prefix FROM. Return the relocated directory if it exists,
529 otherwise return null. */
530
531 static char *
532 get_relative_sysroot (const char *from ATTRIBUTE_UNUSED)
533 {
534 #ifdef TARGET_SYSTEM_ROOT_RELOCATABLE
535 char *path;
536 struct stat s;
537
538 path = make_relative_prefix (program_name, from, TARGET_SYSTEM_ROOT);
539 if (path)
540 {
541 if (stat (path, &s) == 0 && S_ISDIR (s.st_mode))
542 return path;
543 free (path);
544 }
545 #endif
546 return 0;
547 }
548
549 /* Return the sysroot directory. Return "" if no sysroot is being used. */
550
551 static const char *
552 get_sysroot (int argc, char **argv)
553 {
554 int i;
555 const char *path;
556
557 for (i = 1; i < argc; i++)
558 if (CONST_STRNEQ (argv[i], "--sysroot="))
559 return argv[i] + strlen ("--sysroot=");
560
561 path = get_relative_sysroot (BINDIR);
562 if (path)
563 return path;
564
565 path = get_relative_sysroot (TOOLBINDIR);
566 if (path)
567 return path;
568
569 return TARGET_SYSTEM_ROOT;
570 }
571
572 /* We need to find any explicitly given emulation in order to initialize the
573 state that's needed by the lex&yacc argument parser (parse_args). */
574
575 static char *
576 get_emulation (int argc, char **argv)
577 {
578 char *emulation;
579 int i;
580
581 emulation = getenv (EMULATION_ENVIRON);
582 if (emulation == NULL)
583 emulation = DEFAULT_EMULATION;
584
585 for (i = 1; i < argc; i++)
586 {
587 if (CONST_STRNEQ (argv[i], "-m"))
588 {
589 if (argv[i][2] == '\0')
590 {
591 /* -m EMUL */
592 if (i < argc - 1)
593 {
594 emulation = argv[i + 1];
595 i++;
596 }
597 else
598 einfo (_("%P%F: missing argument to -m\n"));
599 }
600 else if (strcmp (argv[i], "-mips1") == 0
601 || strcmp (argv[i], "-mips2") == 0
602 || strcmp (argv[i], "-mips3") == 0
603 || strcmp (argv[i], "-mips4") == 0
604 || strcmp (argv[i], "-mips5") == 0
605 || strcmp (argv[i], "-mips32") == 0
606 || strcmp (argv[i], "-mips32r2") == 0
607 || strcmp (argv[i], "-mips64") == 0
608 || strcmp (argv[i], "-mips64r2") == 0)
609 {
610 /* FIXME: The arguments -mips1, -mips2, -mips3, etc. are
611 passed to the linker by some MIPS compilers. They
612 generally tell the linker to use a slightly different
613 library path. Perhaps someday these should be
614 implemented as emulations; until then, we just ignore
615 the arguments and hope that nobody ever creates
616 emulations named ips1, ips2 or ips3. */
617 }
618 else if (strcmp (argv[i], "-m486") == 0)
619 {
620 /* FIXME: The argument -m486 is passed to the linker on
621 some Linux systems. Hope that nobody creates an
622 emulation named 486. */
623 }
624 else
625 {
626 /* -mEMUL */
627 emulation = &argv[i][2];
628 }
629 }
630 }
631
632 return emulation;
633 }
634
635 void
636 add_ysym (const char *name)
637 {
638 if (link_info.notice_hash == NULL)
639 {
640 link_info.notice_hash =
641 (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table));
642 if (!bfd_hash_table_init_n (link_info.notice_hash,
643 bfd_hash_newfunc,
644 sizeof (struct bfd_hash_entry),
645 61))
646 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
647 }
648
649 if (bfd_hash_lookup (link_info.notice_hash, name, TRUE, TRUE) == NULL)
650 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
651 }
652
653 void
654 add_ignoresym (struct bfd_link_info *info, const char *name)
655 {
656 if (info->ignore_hash == NULL)
657 {
658 info->ignore_hash = xmalloc (sizeof (struct bfd_hash_table));
659 if (! bfd_hash_table_init_n (info->ignore_hash,
660 bfd_hash_newfunc,
661 sizeof (struct bfd_hash_entry),
662 61))
663 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
664 }
665
666 if (bfd_hash_lookup (info->ignore_hash, name, TRUE, TRUE) == NULL)
667 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
668 }
669
670 /* Record a symbol to be wrapped, from the --wrap option. */
671
672 void
673 add_wrap (const char *name)
674 {
675 if (link_info.wrap_hash == NULL)
676 {
677 link_info.wrap_hash =
678 (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table));
679 if (!bfd_hash_table_init_n (link_info.wrap_hash,
680 bfd_hash_newfunc,
681 sizeof (struct bfd_hash_entry),
682 61))
683 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
684 }
685
686 if (bfd_hash_lookup (link_info.wrap_hash, name, TRUE, TRUE) == NULL)
687 einfo (_("%P%F: bfd_hash_lookup failed: %E\n"));
688 }
689
690 /* Handle the -retain-symbols-file option. */
691
692 void
693 add_keepsyms_file (const char *filename)
694 {
695 FILE *file;
696 char *buf;
697 size_t bufsize;
698 int c;
699
700 if (link_info.strip == strip_some)
701 einfo (_("%X%P: error: duplicate retain-symbols-file\n"));
702
703 file = fopen (filename, "r");
704 if (file == NULL)
705 {
706 bfd_set_error (bfd_error_system_call);
707 einfo ("%X%P: %s: %E\n", filename);
708 return;
709 }
710
711 link_info.keep_hash = (struct bfd_hash_table *)
712 xmalloc (sizeof (struct bfd_hash_table));
713 if (!bfd_hash_table_init (link_info.keep_hash, bfd_hash_newfunc,
714 sizeof (struct bfd_hash_entry)))
715 einfo (_("%P%F: bfd_hash_table_init failed: %E\n"));
716
717 bufsize = 100;
718 buf = (char *) xmalloc (bufsize);
719
720 c = getc (file);
721 while (c != EOF)
722 {
723 while (ISSPACE (c))
724 c = getc (file);
725
726 if (c != EOF)
727 {
728 size_t len = 0;
729
730 while (! ISSPACE (c) && c != EOF)
731 {
732 buf[len] = c;
733 ++len;
734 if (len >= bufsize)
735 {
736 bufsize *= 2;
737 buf = (char *) xrealloc (buf, bufsize);
738 }
739 c = getc (file);
740 }
741
742 buf[len] = '\0';
743
744 if (bfd_hash_lookup (link_info.keep_hash, buf, TRUE, TRUE) == NULL)
745 einfo (_("%P%F: bfd_hash_lookup for insertion failed: %E\n"));
746 }
747 }
748
749 if (link_info.strip != strip_none)
750 einfo (_("%P: `-retain-symbols-file' overrides `-s' and `-S'\n"));
751
752 free (buf);
753 link_info.strip = strip_some;
754 fclose (file);
755 }
756 \f
757 /* Callbacks from the BFD linker routines. */
758
759 /* This is called when BFD has decided to include an archive member in
760 a link. */
761
762 static bfd_boolean
763 add_archive_element (struct bfd_link_info *info,
764 bfd *abfd,
765 const char *name,
766 bfd **subsbfd ATTRIBUTE_UNUSED)
767 {
768 lang_input_statement_type *input;
769 lang_input_statement_type orig_input;
770
771 input = (lang_input_statement_type *)
772 xcalloc (1, sizeof (lang_input_statement_type));
773 input->filename = abfd->filename;
774 input->local_sym_name = abfd->filename;
775 input->the_bfd = abfd;
776
777 /* Save the original data for trace files/tries below, as plugins
778 (if enabled) may possibly alter it to point to a replacement
779 BFD, but we still want to output the original BFD filename. */
780 orig_input = *input;
781 #ifdef ENABLE_PLUGINS
782 if (plugin_active_plugins_p () && !no_more_claiming)
783 {
784 /* We must offer this archive member to the plugins to claim. */
785 const char *filename = (bfd_my_archive (abfd) != NULL
786 ? bfd_my_archive (abfd)->filename : abfd->filename);
787 int fd = open (filename, O_RDONLY | O_BINARY);
788 if (fd >= 0)
789 {
790 struct ld_plugin_input_file file;
791
792 /* Offset and filesize must refer to the individual archive
793 member, not the whole file, and must exclude the header.
794 Fortunately for us, that is how the data is stored in the
795 origin field of the bfd and in the arelt_data. */
796 file.name = filename;
797 file.offset = abfd->origin;
798 file.filesize = arelt_size (abfd);
799 file.fd = fd;
800 plugin_maybe_claim (&file, input);
801 if (input->flags.claimed)
802 {
803 input->flags.claim_archive = TRUE;
804 *subsbfd = input->the_bfd;
805 }
806 }
807 }
808 #endif /* ENABLE_PLUGINS */
809
810 ldlang_add_file (input);
811
812 if (config.map_file != NULL)
813 {
814 static bfd_boolean header_printed;
815 struct bfd_link_hash_entry *h;
816 bfd *from;
817 int len;
818
819 h = bfd_link_hash_lookup (info->hash, name, FALSE, FALSE, TRUE);
820
821 if (h == NULL)
822 from = NULL;
823 else
824 {
825 switch (h->type)
826 {
827 default:
828 from = NULL;
829 break;
830
831 case bfd_link_hash_defined:
832 case bfd_link_hash_defweak:
833 from = h->u.def.section->owner;
834 break;
835
836 case bfd_link_hash_undefined:
837 case bfd_link_hash_undefweak:
838 from = h->u.undef.abfd;
839 break;
840
841 case bfd_link_hash_common:
842 from = h->u.c.p->section->owner;
843 break;
844 }
845 }
846
847 if (! header_printed)
848 {
849 char buf[100];
850
851 sprintf (buf, _("Archive member included "
852 "to satisfy reference by file (symbol)\n\n"));
853 minfo ("%s", buf);
854 header_printed = TRUE;
855 }
856
857 if (bfd_my_archive (abfd) == NULL)
858 {
859 minfo ("%s", bfd_get_filename (abfd));
860 len = strlen (bfd_get_filename (abfd));
861 }
862 else
863 {
864 minfo ("%s(%s)", bfd_get_filename (bfd_my_archive (abfd)),
865 bfd_get_filename (abfd));
866 len = (strlen (bfd_get_filename (bfd_my_archive (abfd)))
867 + strlen (bfd_get_filename (abfd))
868 + 2);
869 }
870
871 if (len >= 29)
872 {
873 print_nl ();
874 len = 0;
875 }
876 while (len < 30)
877 {
878 print_space ();
879 ++len;
880 }
881
882 if (from != NULL)
883 minfo ("%B ", from);
884 if (h != NULL)
885 minfo ("(%T)\n", h->root.string);
886 else
887 minfo ("(%s)\n", name);
888 }
889
890 if (trace_files || verbose)
891 info_msg ("%I\n", &orig_input);
892 return TRUE;
893 }
894
895 /* This is called when BFD has discovered a symbol which is defined
896 multiple times. */
897
898 static bfd_boolean
899 multiple_definition (struct bfd_link_info *info,
900 struct bfd_link_hash_entry *h,
901 bfd *nbfd,
902 asection *nsec,
903 bfd_vma nval)
904 {
905 const char *name;
906 bfd *obfd;
907 asection *osec;
908 bfd_vma oval;
909
910 if (info->allow_multiple_definition)
911 return TRUE;
912
913 switch (h->type)
914 {
915 case bfd_link_hash_defined:
916 osec = h->u.def.section;
917 oval = h->u.def.value;
918 obfd = h->u.def.section->owner;
919 break;
920 case bfd_link_hash_indirect:
921 osec = bfd_ind_section_ptr;
922 oval = 0;
923 obfd = NULL;
924 break;
925 default:
926 abort ();
927 }
928
929 /* Ignore a redefinition of an absolute symbol to the
930 same value; it's harmless. */
931 if (h->type == bfd_link_hash_defined
932 && bfd_is_abs_section (osec)
933 && bfd_is_abs_section (nsec)
934 && nval == oval)
935 return TRUE;
936
937 /* If either section has the output_section field set to
938 bfd_abs_section_ptr, it means that the section is being
939 discarded, and this is not really a multiple definition at all.
940 FIXME: It would be cleaner to somehow ignore symbols defined in
941 sections which are being discarded. */
942 if ((osec->output_section != NULL
943 && ! bfd_is_abs_section (osec)
944 && bfd_is_abs_section (osec->output_section))
945 || (nsec->output_section != NULL
946 && ! bfd_is_abs_section (nsec)
947 && bfd_is_abs_section (nsec->output_section)))
948 return TRUE;
949
950 name = h->root.string;
951 if (nbfd == NULL)
952 {
953 nbfd = obfd;
954 nsec = osec;
955 nval = oval;
956 obfd = NULL;
957 }
958 einfo (_("%X%C: multiple definition of `%T'\n"),
959 nbfd, nsec, nval, name);
960 if (obfd != NULL)
961 einfo (_("%D: first defined here\n"), obfd, osec, oval);
962
963 if (RELAXATION_ENABLED_BY_USER)
964 {
965 einfo (_("%P: Disabling relaxation: it will not work with multiple definitions\n"));
966 DISABLE_RELAXATION;
967 }
968
969 return TRUE;
970 }
971
972 /* This is called when there is a definition of a common symbol, or
973 when a common symbol is found for a symbol that is already defined,
974 or when two common symbols are found. We only do something if
975 -warn-common was used. */
976
977 static bfd_boolean
978 multiple_common (struct bfd_link_info *info ATTRIBUTE_UNUSED,
979 struct bfd_link_hash_entry *h,
980 bfd *nbfd,
981 enum bfd_link_hash_type ntype,
982 bfd_vma nsize)
983 {
984 const char *name;
985 bfd *obfd;
986 enum bfd_link_hash_type otype;
987 bfd_vma osize;
988
989 if (!config.warn_common)
990 return TRUE;
991
992 name = h->root.string;
993 otype = h->type;
994 if (otype == bfd_link_hash_common)
995 {
996 obfd = h->u.c.p->section->owner;
997 osize = h->u.c.size;
998 }
999 else if (otype == bfd_link_hash_defined
1000 || otype == bfd_link_hash_defweak)
1001 {
1002 obfd = h->u.def.section->owner;
1003 osize = 0;
1004 }
1005 else
1006 {
1007 /* FIXME: It would nice if we could report the BFD which defined
1008 an indirect symbol, but we don't have anywhere to store the
1009 information. */
1010 obfd = NULL;
1011 osize = 0;
1012 }
1013
1014 if (ntype == bfd_link_hash_defined
1015 || ntype == bfd_link_hash_defweak
1016 || ntype == bfd_link_hash_indirect)
1017 {
1018 ASSERT (otype == bfd_link_hash_common);
1019 einfo (_("%B: warning: definition of `%T' overriding common\n"),
1020 nbfd, name);
1021 if (obfd != NULL)
1022 einfo (_("%B: warning: common is here\n"), obfd);
1023 }
1024 else if (otype == bfd_link_hash_defined
1025 || otype == bfd_link_hash_defweak
1026 || otype == bfd_link_hash_indirect)
1027 {
1028 ASSERT (ntype == bfd_link_hash_common);
1029 einfo (_("%B: warning: common of `%T' overridden by definition\n"),
1030 nbfd, name);
1031 if (obfd != NULL)
1032 einfo (_("%B: warning: defined here\n"), obfd);
1033 }
1034 else
1035 {
1036 ASSERT (otype == bfd_link_hash_common && ntype == bfd_link_hash_common);
1037 if (osize > nsize)
1038 {
1039 einfo (_("%B: warning: common of `%T' overridden by larger common\n"),
1040 nbfd, name);
1041 if (obfd != NULL)
1042 einfo (_("%B: warning: larger common is here\n"), obfd);
1043 }
1044 else if (nsize > osize)
1045 {
1046 einfo (_("%B: warning: common of `%T' overriding smaller common\n"),
1047 nbfd, name);
1048 if (obfd != NULL)
1049 einfo (_("%B: warning: smaller common is here\n"), obfd);
1050 }
1051 else
1052 {
1053 einfo (_("%B: warning: multiple common of `%T'\n"), nbfd, name);
1054 if (obfd != NULL)
1055 einfo (_("%B: warning: previous common is here\n"), obfd);
1056 }
1057 }
1058
1059 return TRUE;
1060 }
1061
1062 /* This is called when BFD has discovered a set element. H is the
1063 entry in the linker hash table for the set. SECTION and VALUE
1064 represent a value which should be added to the set. */
1065
1066 static bfd_boolean
1067 add_to_set (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1068 struct bfd_link_hash_entry *h,
1069 bfd_reloc_code_real_type reloc,
1070 bfd *abfd,
1071 asection *section,
1072 bfd_vma value)
1073 {
1074 if (config.warn_constructors)
1075 einfo (_("%P: warning: global constructor %s used\n"),
1076 h->root.string);
1077
1078 if (! config.build_constructors)
1079 return TRUE;
1080
1081 ldctor_add_set_entry (h, reloc, NULL, section, value);
1082
1083 if (h->type == bfd_link_hash_new)
1084 {
1085 h->type = bfd_link_hash_undefined;
1086 h->u.undef.abfd = abfd;
1087 /* We don't call bfd_link_add_undef to add this to the list of
1088 undefined symbols because we are going to define it
1089 ourselves. */
1090 }
1091
1092 return TRUE;
1093 }
1094
1095 /* This is called when BFD has discovered a constructor. This is only
1096 called for some object file formats--those which do not handle
1097 constructors in some more clever fashion. This is similar to
1098 adding an element to a set, but less general. */
1099
1100 static bfd_boolean
1101 constructor_callback (struct bfd_link_info *info,
1102 bfd_boolean constructor,
1103 const char *name,
1104 bfd *abfd,
1105 asection *section,
1106 bfd_vma value)
1107 {
1108 char *s;
1109 struct bfd_link_hash_entry *h;
1110 char set_name[1 + sizeof "__CTOR_LIST__"];
1111
1112 if (config.warn_constructors)
1113 einfo (_("%P: warning: global constructor %s used\n"), name);
1114
1115 if (! config.build_constructors)
1116 return TRUE;
1117
1118 /* Ensure that BFD_RELOC_CTOR exists now, so that we can give a
1119 useful error message. */
1120 if (bfd_reloc_type_lookup (info->output_bfd, BFD_RELOC_CTOR) == NULL
1121 && (info->relocatable
1122 || bfd_reloc_type_lookup (abfd, BFD_RELOC_CTOR) == NULL))
1123 einfo (_("%P%F: BFD backend error: BFD_RELOC_CTOR unsupported\n"));
1124
1125 s = set_name;
1126 if (bfd_get_symbol_leading_char (abfd) != '\0')
1127 *s++ = bfd_get_symbol_leading_char (abfd);
1128 if (constructor)
1129 strcpy (s, "__CTOR_LIST__");
1130 else
1131 strcpy (s, "__DTOR_LIST__");
1132
1133 h = bfd_link_hash_lookup (info->hash, set_name, TRUE, TRUE, TRUE);
1134 if (h == (struct bfd_link_hash_entry *) NULL)
1135 einfo (_("%P%F: bfd_link_hash_lookup failed: %E\n"));
1136 if (h->type == bfd_link_hash_new)
1137 {
1138 h->type = bfd_link_hash_undefined;
1139 h->u.undef.abfd = abfd;
1140 /* We don't call bfd_link_add_undef to add this to the list of
1141 undefined symbols because we are going to define it
1142 ourselves. */
1143 }
1144
1145 ldctor_add_set_entry (h, BFD_RELOC_CTOR, name, section, value);
1146 return TRUE;
1147 }
1148
1149 /* A structure used by warning_callback to pass information through
1150 bfd_map_over_sections. */
1151
1152 struct warning_callback_info
1153 {
1154 bfd_boolean found;
1155 const char *warning;
1156 const char *symbol;
1157 asymbol **asymbols;
1158 };
1159
1160 /* Look through the relocs to see if we can find a plausible address
1161 for SYMBOL in ABFD. Return TRUE if found. Otherwise return FALSE. */
1162
1163 static bfd_boolean
1164 symbol_warning (const char *warning, const char *symbol, bfd *abfd)
1165 {
1166 struct warning_callback_info cinfo;
1167
1168 if (!bfd_generic_link_read_symbols (abfd))
1169 einfo (_("%B%F: could not read symbols: %E\n"), abfd);
1170
1171 cinfo.found = FALSE;
1172 cinfo.warning = warning;
1173 cinfo.symbol = symbol;
1174 cinfo.asymbols = bfd_get_outsymbols (abfd);
1175 bfd_map_over_sections (abfd, warning_find_reloc, &cinfo);
1176 return cinfo.found;
1177 }
1178
1179 /* This is called when there is a reference to a warning symbol. */
1180
1181 static bfd_boolean
1182 warning_callback (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1183 const char *warning,
1184 const char *symbol,
1185 bfd *abfd,
1186 asection *section,
1187 bfd_vma address)
1188 {
1189 /* This is a hack to support warn_multiple_gp. FIXME: This should
1190 have a cleaner interface, but what? */
1191 if (! config.warn_multiple_gp
1192 && strcmp (warning, "using multiple gp values") == 0)
1193 return TRUE;
1194
1195 if (section != NULL)
1196 einfo ("%C: %s%s\n", abfd, section, address, _("warning: "), warning);
1197 else if (abfd == NULL)
1198 einfo ("%P: %s%s\n", _("warning: "), warning);
1199 else if (symbol == NULL)
1200 einfo ("%B: %s%s\n", abfd, _("warning: "), warning);
1201 else if (! symbol_warning (warning, symbol, abfd))
1202 {
1203 bfd *b;
1204 /* Search all input files for a reference to SYMBOL. */
1205 for (b = info->input_bfds; b; b = b->link_next)
1206 if (b != abfd && symbol_warning (warning, symbol, b))
1207 return TRUE;
1208 einfo ("%B: %s%s\n", abfd, _("warning: "), warning);
1209 }
1210
1211 return TRUE;
1212 }
1213
1214 /* This is called by warning_callback for each section. It checks the
1215 relocs of the section to see if it can find a reference to the
1216 symbol which triggered the warning. If it can, it uses the reloc
1217 to give an error message with a file and line number. */
1218
1219 static void
1220 warning_find_reloc (bfd *abfd, asection *sec, void *iarg)
1221 {
1222 struct warning_callback_info *info = (struct warning_callback_info *) iarg;
1223 long relsize;
1224 arelent **relpp;
1225 long relcount;
1226 arelent **p, **pend;
1227
1228 if (info->found)
1229 return;
1230
1231 relsize = bfd_get_reloc_upper_bound (abfd, sec);
1232 if (relsize < 0)
1233 einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1234 if (relsize == 0)
1235 return;
1236
1237 relpp = (arelent **) xmalloc (relsize);
1238 relcount = bfd_canonicalize_reloc (abfd, sec, relpp, info->asymbols);
1239 if (relcount < 0)
1240 einfo (_("%B%F: could not read relocs: %E\n"), abfd);
1241
1242 p = relpp;
1243 pend = p + relcount;
1244 for (; p < pend && *p != NULL; p++)
1245 {
1246 arelent *q = *p;
1247
1248 if (q->sym_ptr_ptr != NULL
1249 && *q->sym_ptr_ptr != NULL
1250 && strcmp (bfd_asymbol_name (*q->sym_ptr_ptr), info->symbol) == 0)
1251 {
1252 /* We found a reloc for the symbol we are looking for. */
1253 einfo ("%C: %s%s\n", abfd, sec, q->address, _("warning: "),
1254 info->warning);
1255 info->found = TRUE;
1256 break;
1257 }
1258 }
1259
1260 free (relpp);
1261 }
1262
1263 /* This is called when an undefined symbol is found. */
1264
1265 static bfd_boolean
1266 undefined_symbol (struct bfd_link_info *info,
1267 const char *name,
1268 bfd *abfd,
1269 asection *section,
1270 bfd_vma address,
1271 bfd_boolean error)
1272 {
1273 static char *error_name;
1274 static unsigned int error_count;
1275
1276 #define MAX_ERRORS_IN_A_ROW 5
1277
1278 if (info->ignore_hash != NULL
1279 && bfd_hash_lookup (info->ignore_hash, name, FALSE, FALSE) != NULL)
1280 return TRUE;
1281
1282 if (config.warn_once)
1283 {
1284 /* Only warn once about a particular undefined symbol. */
1285 add_ignoresym (info, name);
1286 }
1287
1288 /* We never print more than a reasonable number of errors in a row
1289 for a single symbol. */
1290 if (error_name != NULL
1291 && strcmp (name, error_name) == 0)
1292 ++error_count;
1293 else
1294 {
1295 error_count = 0;
1296 if (error_name != NULL)
1297 free (error_name);
1298 error_name = xstrdup (name);
1299 }
1300
1301 if (section != NULL)
1302 {
1303 if (error_count < MAX_ERRORS_IN_A_ROW)
1304 {
1305 if (error)
1306 einfo (_("%X%C: undefined reference to `%T'\n"),
1307 abfd, section, address, name);
1308 else
1309 einfo (_("%C: warning: undefined reference to `%T'\n"),
1310 abfd, section, address, name);
1311 }
1312 else if (error_count == MAX_ERRORS_IN_A_ROW)
1313 {
1314 if (error)
1315 einfo (_("%X%D: more undefined references to `%T' follow\n"),
1316 abfd, section, address, name);
1317 else
1318 einfo (_("%D: warning: more undefined references to `%T' follow\n"),
1319 abfd, section, address, name);
1320 }
1321 else if (error)
1322 einfo ("%X");
1323 }
1324 else
1325 {
1326 if (error_count < MAX_ERRORS_IN_A_ROW)
1327 {
1328 if (error)
1329 einfo (_("%X%B: undefined reference to `%T'\n"),
1330 abfd, name);
1331 else
1332 einfo (_("%B: warning: undefined reference to `%T'\n"),
1333 abfd, name);
1334 }
1335 else if (error_count == MAX_ERRORS_IN_A_ROW)
1336 {
1337 if (error)
1338 einfo (_("%X%B: more undefined references to `%T' follow\n"),
1339 abfd, name);
1340 else
1341 einfo (_("%B: warning: more undefined references to `%T' follow\n"),
1342 abfd, name);
1343 }
1344 else if (error)
1345 einfo ("%X");
1346 }
1347
1348 return TRUE;
1349 }
1350
1351 /* Counter to limit the number of relocation overflow error messages
1352 to print. Errors are printed as it is decremented. When it's
1353 called and the counter is zero, a final message is printed
1354 indicating more relocations were omitted. When it gets to -1, no
1355 such errors are printed. If it's initially set to a value less
1356 than -1, all such errors will be printed (--verbose does this). */
1357
1358 int overflow_cutoff_limit = 10;
1359
1360 /* This is called when a reloc overflows. */
1361
1362 static bfd_boolean
1363 reloc_overflow (struct bfd_link_info *info,
1364 struct bfd_link_hash_entry *entry,
1365 const char *name,
1366 const char *reloc_name,
1367 bfd_vma addend,
1368 bfd *abfd,
1369 asection *section,
1370 bfd_vma address)
1371 {
1372 if (overflow_cutoff_limit == -1)
1373 return TRUE;
1374
1375 einfo ("%X%H:", abfd, section, address);
1376
1377 if (overflow_cutoff_limit >= 0
1378 && overflow_cutoff_limit-- == 0)
1379 {
1380 einfo (_(" additional relocation overflows omitted from the output\n"));
1381 return TRUE;
1382 }
1383
1384 if (entry)
1385 {
1386 while (entry->type == bfd_link_hash_indirect
1387 || entry->type == bfd_link_hash_warning)
1388 entry = entry->u.i.link;
1389 switch (entry->type)
1390 {
1391 case bfd_link_hash_undefined:
1392 case bfd_link_hash_undefweak:
1393 einfo (_(" relocation truncated to fit: %s against undefined symbol `%T'"),
1394 reloc_name, entry->root.string);
1395 break;
1396 case bfd_link_hash_defined:
1397 case bfd_link_hash_defweak:
1398 einfo (_(" relocation truncated to fit: %s against symbol `%T' defined in %A section in %B"),
1399 reloc_name, entry->root.string,
1400 entry->u.def.section,
1401 entry->u.def.section == bfd_abs_section_ptr
1402 ? info->output_bfd : entry->u.def.section->owner);
1403 break;
1404 default:
1405 abort ();
1406 break;
1407 }
1408 }
1409 else
1410 einfo (_(" relocation truncated to fit: %s against `%T'"),
1411 reloc_name, name);
1412 if (addend != 0)
1413 einfo ("+%v", addend);
1414 einfo ("\n");
1415 return TRUE;
1416 }
1417
1418 /* This is called when a dangerous relocation is made. */
1419
1420 static bfd_boolean
1421 reloc_dangerous (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1422 const char *message,
1423 bfd *abfd,
1424 asection *section,
1425 bfd_vma address)
1426 {
1427 einfo (_("%X%H: dangerous relocation: %s\n"),
1428 abfd, section, address, message);
1429 return TRUE;
1430 }
1431
1432 /* This is called when a reloc is being generated attached to a symbol
1433 that is not being output. */
1434
1435 static bfd_boolean
1436 unattached_reloc (struct bfd_link_info *info ATTRIBUTE_UNUSED,
1437 const char *name,
1438 bfd *abfd,
1439 asection *section,
1440 bfd_vma address)
1441 {
1442 einfo (_("%X%H: reloc refers to symbol `%T' which is not being output\n"),
1443 abfd, section, address, name);
1444 return TRUE;
1445 }
1446
1447 /* This is called if link_info.notice_all is set, or when a symbol in
1448 link_info.notice_hash is found. Symbols are put in notice_hash
1449 using the -y option, while notice_all is set if the --cref option
1450 has been supplied, or if there are any NOCROSSREFS sections in the
1451 linker script; and if plugins are active, since they need to monitor
1452 all references from non-IR files. */
1453
1454 static bfd_boolean
1455 notice (struct bfd_link_info *info,
1456 struct bfd_link_hash_entry *h,
1457 bfd *abfd,
1458 asection *section,
1459 bfd_vma value,
1460 flagword flags ATTRIBUTE_UNUSED,
1461 const char *string ATTRIBUTE_UNUSED)
1462 {
1463 const char *name;
1464
1465 if (h == NULL)
1466 {
1467 if (command_line.cref || nocrossref_list != NULL)
1468 return handle_asneeded_cref (abfd, (enum notice_asneeded_action) value);
1469 return TRUE;
1470 }
1471
1472 name = h->root.string;
1473 if (info->notice_hash != NULL
1474 && bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL)
1475 {
1476 if (bfd_is_und_section (section))
1477 einfo ("%B: reference to %s\n", abfd, name);
1478 else
1479 einfo ("%B: definition of %s\n", abfd, name);
1480 }
1481
1482 if (command_line.cref || nocrossref_list != NULL)
1483 add_cref (name, abfd, section, value);
1484
1485 return TRUE;
1486 }
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