aboutsummaryrefslogtreecommitdiff
path: root/gold/options.cc
blob: 8d18c11fbc2f758445263c7a84b1ce7220877f90 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
// options.c -- handle command line options for gold

// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.

// This file is part of gold.

// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.

#include "gold.h"

#include <cstdlib>
#include <cstring>
#include <vector>
#include <iostream>
#include <sys/stat.h>
#include "filenames.h"
#include "libiberty.h"
#include "demangle.h"
#include "../bfd/bfdver.h"

#include "debug.h"
#include "script.h"
#include "target-select.h"
#include "options.h"

namespace gold
{

General_options
Position_dependent_options::default_options_;

namespace options
{

// This global variable is set up as General_options is constructed.
static std::vector<const One_option*> registered_options;

// These are set up at the same time -- the variables that accept one
// dash, two, or require -z.  A single variable may be in more than
// one of thes data structures.
typedef Unordered_map<std::string, One_option*> Option_map;
static Option_map* long_options = NULL;
static One_option* short_options[128];

void
One_option::register_option()
{
  registered_options.push_back(this);

  // We can't make long_options a static Option_map because we can't
  // guarantee that will be initialized before register_option() is
  // first called.
  if (long_options == NULL)
    long_options = new Option_map;

  // TWO_DASHES means that two dashes are preferred, but one is ok too.
  if (!this->longname.empty())
    (*long_options)[this->longname] = this;

  const int shortname_as_int = static_cast<int>(this->shortname);
  gold_assert(shortname_as_int >= 0 && shortname_as_int < 128);
  if (this->shortname != '\0')
    short_options[shortname_as_int] = this;
}

void
One_option::print() const
{
  bool comma = false;
  printf("  ");
  int len = 2;
  if (this->shortname != '\0')
    {
      len += printf("-%c", this->shortname);
      if (this->helparg)
        {
          // -z takes long-names only.
          gold_assert(this->dashes != DASH_Z);
          len += printf(" %s", gettext(this->helparg));
        }
      comma = true;
    }
  if (!this->longname.empty()
      && !(this->longname[0] == this->shortname
	   && this->longname[1] == '\0'))
    {
      if (comma)
        len += printf(", ");
      switch (this->dashes)
        {
        case options::ONE_DASH: case options::EXACTLY_ONE_DASH:
          len += printf("-");
          break;
        case options::TWO_DASHES: case options::EXACTLY_TWO_DASHES:
          len += printf("--");
          break;
        case options::DASH_Z:
          len += printf("-z ");
          break;
        default:
          gold_unreachable();
        }
      len += printf("%s", this->longname.c_str());
      if (this->helparg)
        {
          // For most options, we print "--frob FOO".  But for -z
          // we print "-z frob=FOO".
          len += printf("%c%s", this->dashes == options::DASH_Z ? '=' : ' ',
                        gettext(this->helparg));
        }
    }

  if (len >= 30)
    {
      printf("\n");
      len = 0;
    }
  for (; len < 30; ++len)
    std::putchar(' ');

  // TODO: if we're boolean, add " (default)" when appropriate.
  printf("%s\n", gettext(this->helpstring));
}

void
help()
{
  printf(_("Usage: %s [options] file...\nOptions:\n"), gold::program_name);

  std::vector<const One_option*>::const_iterator it;
  for (it = registered_options.begin(); it != registered_options.end(); ++it)
    (*it)->print();

  // config.guess and libtool.m4 look in ld --help output for the
  // string "supported targets".
  printf(_("%s: supported targets:"), gold::program_name);
  std::vector<const char*> supported_names;
  gold::supported_target_names(&supported_names);
  for (std::vector<const char*>::const_iterator p = supported_names.begin();
       p != supported_names.end();
       ++p)
    printf(" %s", *p);
  printf("\n");

  // REPORT_BUGS_TO is defined in bfd/bfdver.h.
  const char* report = REPORT_BUGS_TO;
  if (*report != '\0')
    printf(_("Report bugs to %s\n"), report);
}

// For bool, arg will be NULL (boolean options take no argument);
// we always just set to true.
void
parse_bool(const char*, const char*, bool* retval)
{
  *retval = true;
}

void
parse_uint(const char* option_name, const char* arg, int* retval)
{
  char* endptr;
  *retval = strtol(arg, &endptr, 0);
  if (*endptr != '\0' || retval < 0)
    gold_fatal(_("%s: invalid option value (expected an integer): %s"),
               option_name, arg);
}

void
parse_uint64(const char* option_name, const char* arg, uint64_t *retval)
{
  char* endptr;
  *retval = strtoull(arg, &endptr, 0);
  if (*endptr != '\0')
    gold_fatal(_("%s: invalid option value (expected an integer): %s"),
               option_name, arg);
}

void
parse_double(const char* option_name, const char* arg, double* retval)
{
  char* endptr;
  *retval = strtod(arg, &endptr);
  if (*endptr != '\0')
    gold_fatal(_("%s: invalid option value "
		 "(expected a floating point number): %s"),
	       option_name, arg);
}

void
parse_string(const char* option_name, const char* arg, const char** retval)
{
  if (*arg == '\0')
    gold_fatal(_("%s: must take a non-empty argument"), option_name);
  *retval = arg;
}

void
parse_optional_string(const char*, const char* arg, const char** retval)
{
  *retval = arg;
}

void
parse_dirlist(const char*, const char* arg, Dir_list* retval)
{
  retval->push_back(Search_directory(arg, false));
}

void
parse_set(const char*, const char* arg, String_set* retval)
{
  retval->insert(std::string(arg));
}

void
parse_choices(const char* option_name, const char* arg, const char** retval,
              const char* choices[], int num_choices)
{
  for (int i = 0; i < num_choices; i++)
    if (strcmp(choices[i], arg) == 0)
      {
        *retval = arg;
        return;
      }

  // If we get here, the user did not enter a valid choice, so we die.
  std::string choices_list;
  for (int i = 0; i < num_choices; i++)
    {
      choices_list += choices[i];
      if (i != num_choices - 1)
        choices_list += ", ";
    }
  gold_fatal(_("%s: must take one of the following arguments: %s"),
             option_name, choices_list.c_str());
}

} // End namespace options.

// Define the handler for "special" options (set via DEFINE_special).

void
General_options::parse_help(const char*, const char*, Command_line*)
{
  options::help();
  ::exit(EXIT_SUCCESS);
}

void
General_options::parse_version(const char* opt, const char*, Command_line*)
{
  gold::print_version(opt[0] == '-' && opt[1] == 'v');
  ::exit(EXIT_SUCCESS);
}

void
General_options::parse_V(const char*, const char*, Command_line*)
{
  gold::print_version(true);
  printf(_("  Supported targets:\n"));
  std::vector<const char*> supported_names;
  gold::supported_target_names(&supported_names);
  for (std::vector<const char*>::const_iterator p = supported_names.begin();
       p != supported_names.end();
       ++p)
    printf("   %s\n", *p);
}

void
General_options::parse_defsym(const char*, const char* arg,
                              Command_line* cmdline)
{
  cmdline->script_options().define_symbol(arg);
}

void
General_options::parse_library(const char*, const char* arg,
                               Command_line* cmdline)
{
  Input_file_argument file(arg, true, "", false, *this);
  cmdline->inputs().add_file(file);
}

void
General_options::parse_R(const char* option, const char* arg,
                         Command_line* cmdline)
{
  struct stat s;
  if (::stat(arg, &s) != 0 || S_ISDIR(s.st_mode))
    this->add_to_rpath(arg);
  else
    this->parse_just_symbols(option, arg, cmdline);
}

void
General_options::parse_just_symbols(const char*, const char* arg,
                                    Command_line* cmdline)
{
  Input_file_argument file(arg, false, "", true, *this);
  cmdline->inputs().add_file(file);
}

void
General_options::parse_static(const char*, const char*, Command_line*)
{
  this->set_static(true);
}

void
General_options::parse_script(const char*, const char* arg,
                              Command_line* cmdline)
{
  if (!read_commandline_script(arg, cmdline))
    gold::gold_fatal(_("unable to parse script file %s"), arg);
}

void
General_options::parse_version_script(const char*, const char* arg,
                                      Command_line* cmdline)
{
  if (!read_version_script(arg, cmdline))
    gold::gold_fatal(_("unable to parse version script file %s"), arg);
}

void
General_options::parse_start_group(const char*, const char*,
                                   Command_line* cmdline)
{
  cmdline->inputs().start_group();
}

void
General_options::parse_end_group(const char*, const char*,
                                 Command_line* cmdline)
{
  cmdline->inputs().end_group();
}

} // End namespace gold.

namespace
{

void
usage()
{
  fprintf(stderr,
          _("%s: use the --help option for usage information\n"),
          gold::program_name);
  ::exit(EXIT_FAILURE);
}

void
usage(const char* msg, const char *opt)
{
  fprintf(stderr,
          _("%s: %s: %s\n"),
          gold::program_name, opt, msg);
  usage();
}

// Recognize input and output target names.  The GNU linker accepts
// these with --format and --oformat.  This code is intended to be
// minimally compatible.  In practice for an ELF target this would be
// the same target as the input files; that name always start with
// "elf".  Non-ELF targets would be "srec", "symbolsrec", "tekhex",
// "binary", "ihex".

gold::General_options::Object_format
string_to_object_format(const char* arg)
{
  if (strncmp(arg, "elf", 3) == 0)
    return gold::General_options::OBJECT_FORMAT_ELF;
  else if (strcmp(arg, "binary") == 0)
    return gold::General_options::OBJECT_FORMAT_BINARY;
  else
    {
      gold::gold_error(_("format '%s' not supported; treating as elf "
                         "(supported formats: elf, binary)"),
                       arg);
      return gold::General_options::OBJECT_FORMAT_ELF;
    }
}

// If the default sysroot is relocatable, try relocating it based on
// the prefix FROM.

char*
get_relative_sysroot(const char* from)
{
  char* path = make_relative_prefix(gold::program_name, from,
                                    TARGET_SYSTEM_ROOT);
  if (path != NULL)
    {
      struct stat s;
      if (::stat(path, &s) == 0 && S_ISDIR(s.st_mode))
        return path;
      free(path);
    }

  return NULL;
}

// Return the default sysroot.  This is set by the --with-sysroot
// option to configure.  Note we do not free the return value of
// get_relative_sysroot, which is a small memory leak, but is
// necessary since we store this pointer directly in General_options.

const char*
get_default_sysroot()
{
  const char* sysroot = TARGET_SYSTEM_ROOT;
  if (*sysroot == '\0')
    return NULL;

  if (TARGET_SYSTEM_ROOT_RELOCATABLE)
    {
      char* path = get_relative_sysroot(BINDIR);
      if (path == NULL)
        path = get_relative_sysroot(TOOLBINDIR);
      if (path != NULL)
        return path;
    }

  return sysroot;
}

// Parse a long option.  Such options have the form
// <-|--><option>[=arg].  If "=arg" is not present but the option
// takes an argument, the next word is taken to the be the argument.
// If equals_only is set, then only the <option>=<arg> form is
// accepted, not the <option><space><arg> form.  Returns a One_option
// struct or NULL if argv[i] cannot be parsed as a long option.  In
// the not-NULL case, *arg is set to the option's argument (NULL if
// the option takes no argument), and *i is advanced past this option.
// NOTE: it is safe for argv and arg to point to the same place.
gold::options::One_option*
parse_long_option(int argc, const char** argv, bool equals_only,
                  const char** arg, int* i)
{
  const char* const this_argv = argv[*i];

  const char* equals = strchr(this_argv, '=');
  const char* option_start = this_argv + strspn(this_argv, "-");
  std::string option(option_start,
                     equals ? equals - option_start : strlen(option_start));

  gold::options::Option_map::iterator it
      = gold::options::long_options->find(option);
  if (it == gold::options::long_options->end())
    return NULL;

  gold::options::One_option* retval = it->second;

  // If the dash-count doesn't match, we fail.
  if (this_argv[0] != '-')  // no dashes at all: had better be "-z <longopt>"
    {
      if (retval->dashes != gold::options::DASH_Z)
        return NULL;
    }
  else if (this_argv[1] != '-')   // one dash
    {
      if (retval->dashes != gold::options::ONE_DASH
          && retval->dashes != gold::options::EXACTLY_ONE_DASH
          && retval->dashes != gold::options::TWO_DASHES)
        return NULL;
    }
  else                            // two dashes (or more!)
    {
      if (retval->dashes != gold::options::TWO_DASHES
          && retval->dashes != gold::options::EXACTLY_TWO_DASHES
          && retval->dashes != gold::options::ONE_DASH)
        return NULL;
    }

  // Now that we know the option is good (or else bad in a way that
  // will cause us to die), increment i to point past this argv.
  ++(*i);

  // Figure out the option's argument, if any.
  if (!retval->takes_argument())
    {
      if (equals)
        usage(_("unexpected argument"), this_argv);
      else
        *arg = NULL;
    }
  else
    {
      if (equals)
        *arg = equals + 1;
      else if (retval->takes_optional_argument())
	*arg = retval->default_value;
      else if (*i < argc && !equals_only)
        *arg = argv[(*i)++];
      else
        usage(_("missing argument"), this_argv);
    }

  return retval;
}

// Parse a short option.  Such options have the form -<option>[arg].
// If "arg" is not present but the option takes an argument, the next
// word is taken to the be the argument.  If the option does not take
// an argument, it may be followed by another short option.  Returns a
// One_option struct or NULL if argv[i] cannot be parsed as a short
// option.  In the not-NULL case, *arg is set to the option's argument
// (NULL if the option takes no argument), and *i is advanced past
// this option.  This function keeps *i the same if we parsed a short
// option that does not take an argument, that looks to be followed by
// another short option in the same word.
gold::options::One_option*
parse_short_option(int argc, const char** argv, int pos_in_argv_i,
                   const char** arg, int* i)
{
  const char* const this_argv = argv[*i];

  if (this_argv[0] != '-')
    return NULL;

  // We handle -z as a special case.
  static gold::options::One_option dash_z("", gold::options::DASH_Z,
                                          'z', "", "-z", "Z-OPTION", false,
					  NULL);
  gold::options::One_option* retval = NULL;
  if (this_argv[pos_in_argv_i] == 'z')
    retval = &dash_z;
  else
    {
      const int char_as_int = static_cast<int>(this_argv[pos_in_argv_i]);
      if (char_as_int > 0 && char_as_int < 128)
        retval = gold::options::short_options[char_as_int];
    }

  if (retval == NULL)
    return NULL;

  // Figure out the option's argument, if any.
  if (!retval->takes_argument())
    {
      *arg = NULL;
      // We only advance past this argument if it's the only one in argv.
      if (this_argv[pos_in_argv_i + 1] == '\0')
        ++(*i);
    }
  else
    {
      // If we take an argument, we'll eat up this entire argv entry.
      ++(*i);
      if (this_argv[pos_in_argv_i + 1] != '\0')
        *arg = this_argv + pos_in_argv_i + 1;
      else if (retval->takes_optional_argument())
	*arg = retval->default_value;
      else if (*i < argc)
        *arg = argv[(*i)++];
      else
        usage(_("missing argument"), this_argv);
    }

  // If we're a -z option, we need to parse our argument as a
  // long-option, e.g. "-z stacksize=8192".
  if (retval == &dash_z)
    {
      int dummy_i = 0;
      const char* dash_z_arg = *arg;
      retval = parse_long_option(1, arg, true, arg, &dummy_i);
      if (retval == NULL)
        usage(_("unknown -z option"), dash_z_arg);
    }

  return retval;
}

} // End anonymous namespace.

namespace gold
{

General_options::General_options()
  : execstack_status_(General_options::EXECSTACK_FROM_INPUT), static_(false),
    do_demangle_(false)
{
}

General_options::Object_format
General_options::format_enum() const
{
  return string_to_object_format(this->format());
}

General_options::Object_format
General_options::oformat_enum() const
{
  return string_to_object_format(this->oformat());
}

// Add the sysroot, if any, to the search paths.

void
General_options::add_sysroot()
{
  if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
    {
      this->set_sysroot(get_default_sysroot());
      if (this->sysroot() == NULL || this->sysroot()[0] == '\0')
        return;
    }

  char* canonical_sysroot = lrealpath(this->sysroot());

  for (Dir_list::iterator p = this->library_path_.value.begin();
       p != this->library_path_.value.end();
       ++p)
    p->add_sysroot(this->sysroot(), canonical_sysroot);

  free(canonical_sysroot);
}

// Set up variables and other state that isn't set up automatically by
// the parse routine, and ensure options don't contradict each other
// and are otherwise kosher.

void
General_options::finalize()
{
  // Normalize the strip modifiers.  They have a total order:
  // strip_all > strip_debug > strip_debug_gdb.  If one is true, set
  // all beneath it to true as well.
  if (this->strip_all())
    this->set_strip_debug(true);
  if (this->strip_debug())
    this->set_strip_debug_gdb(true);

  // If the user specifies both -s and -r, convert the -s to -S.
  // -r requires us to keep externally visible symbols!
  if (this->strip_all() && this->relocatable())
    {
      this->set_strip_all(false);
      gold_assert(this->strip_debug());
    }

  // For us, -dc and -dp are synonyms for --define-common.
  if (this->dc())
    this->set_define_common(true);
  if (this->dp())
    this->set_define_common(true);

  // We also set --define-common if we're not relocatable, as long as
  // the user didn't explicitly ask for something different.
  if (!this->user_set_define_common())
    this->set_define_common(!this->relocatable());

  // execstack_status_ is a three-state variable; update it based on
  // -z [no]execstack.
  if (this->execstack())
    this->set_execstack_status(EXECSTACK_YES);
  else if (this->noexecstack())
    this->set_execstack_status(EXECSTACK_NO);

  // Handle the optional argument for --demangle.
  if (this->user_set_demangle())
    {
      this->set_do_demangle(true);
      const char* style = this->demangle();
      if (*style != '\0')
	{
	  enum demangling_styles style_code;

	  style_code = cplus_demangle_name_to_style(style);
	  if (style_code == unknown_demangling)
	    gold_fatal("unknown demangling style '%s'", style);
	  cplus_demangle_set_style(style_code);
	}
    }
  else if (this->user_set_no_demangle())
    this->set_do_demangle(false);
  else
    {
      // Testing COLLECT_NO_DEMANGLE makes our default demangling
      // behaviour identical to that of gcc's linker wrapper.
      this->set_do_demangle(getenv("COLLECT_NO_DEMANGLE") == NULL);
    }

  // If --thread_count is specified, it applies to
  // --thread-count-{initial,middle,final}, though it doesn't override
  // them.
  if (this->thread_count() > 0 && this->thread_count_initial() == 0)
    this->set_thread_count_initial(this->thread_count());
  if (this->thread_count() > 0 && this->thread_count_middle() == 0)
    this->set_thread_count_middle(this->thread_count());
  if (this->thread_count() > 0 && this->thread_count_final() == 0)
    this->set_thread_count_final(this->thread_count());

  // Let's warn if you set the thread-count but we're going to ignore it.
#ifndef ENABLE_THREADS
  if (this->threads())
    {
      gold_warning(_("ignoring --threads: "
		     "%s was compiled without thread support"),
		   program_name);
      this->set_threads(false);
    }
  if (this->thread_count() > 0 || this->thread_count_initial() > 0
      || this->thread_count_middle() > 0 || this->thread_count_final() > 0)
    gold_warning(_("ignoring --thread-count: "
                   "%s was compiled without thread support"),
                 program_name);
#endif

  if (this->user_set_Y())
    {
      std::string s = this->Y();
      if (s.compare(0, 2, "P,") == 0)
	s.erase(0, 2);

      size_t pos = 0;
      size_t next_pos;
      do
	{
	  next_pos = s.find(':', pos);
	  size_t len = (next_pos == std::string::npos
			? next_pos
			: next_pos - pos);
	  if (len != 0)
	    this->add_to_library_path_with_sysroot(s.substr(pos, len).c_str());
	  pos = next_pos + 1;
	}
      while (next_pos != std::string::npos);
    }
  else
    {
      // Even if they don't specify it, we add -L /lib and -L /usr/lib.
      // FIXME: We should only do this when configured in native mode.
      this->add_to_library_path_with_sysroot("/lib");
      this->add_to_library_path_with_sysroot("/usr/lib");
    }

  // Normalize library_path() by adding the sysroot to all directories
  // in the path, as appropriate.
  this->add_sysroot();

  // Now that we've normalized the options, check for contradictory ones.
  if (this->shared() && this->relocatable())
    gold_fatal(_("-shared and -r are incompatible"));

  if (this->oformat_enum() != General_options::OBJECT_FORMAT_ELF
      && (this->shared() || this->relocatable()))
    gold_fatal(_("binary output format not compatible with -shared or -r"));

  if (this->user_set_hash_bucket_empty_fraction()
      && (this->hash_bucket_empty_fraction() < 0.0
	  || this->hash_bucket_empty_fraction() >= 1.0))
    gold_fatal(_("--hash-bucket-empty-fraction value %g out of range "
		 "[0.0, 1.0)"),
	       this->hash_bucket_empty_fraction());

  // FIXME: we can/should be doing a lot more sanity checking here.
}

// Search_directory methods.

// This is called if we have a sysroot.  Apply the sysroot if
// appropriate.  Record whether the directory is in the sysroot.

void
Search_directory::add_sysroot(const char* sysroot,
                              const char* canonical_sysroot)
{
  gold_assert(*sysroot != '\0');
  if (this->put_in_sysroot_)
    {
      if (!IS_DIR_SEPARATOR(this->name_[0])
          && !IS_DIR_SEPARATOR(sysroot[strlen(sysroot) - 1]))
        this->name_ = '/' + this->name_;
      this->name_ = sysroot + this->name_;
      this->is_in_sysroot_ = true;
    }
  else
    {
      // Check whether this entry is in the sysroot.  To do this
      // correctly, we need to use canonical names.  Otherwise we will
      // get confused by the ../../.. paths that gcc tends to use.
      char* canonical_name = lrealpath(this->name_.c_str());
      int canonical_name_len = strlen(canonical_name);
      int canonical_sysroot_len = strlen(canonical_sysroot);
      if (canonical_name_len > canonical_sysroot_len
          && IS_DIR_SEPARATOR(canonical_name[canonical_sysroot_len]))
        {
          canonical_name[canonical_sysroot_len] = '\0';
          if (FILENAME_CMP(canonical_name, canonical_sysroot) == 0)
            this->is_in_sysroot_ = true;
        }
      free(canonical_name);
    }
}

// Input_arguments methods.

// Add a file to the list.

void
Input_arguments::add_file(const Input_file_argument& file)
{
  if (!this->in_group_)
    this->input_argument_list_.push_back(Input_argument(file));
  else
    {
      gold_assert(!this->input_argument_list_.empty());
      gold_assert(this->input_argument_list_.back().is_group());
      this->input_argument_list_.back().group()->add_file(file);
    }
}

// Start a group.

void
Input_arguments::start_group()
{
  if (this->in_group_)
    gold_fatal(_("May not nest groups"));
  Input_file_group* group = new Input_file_group();
  this->input_argument_list_.push_back(Input_argument(group));
  this->in_group_ = true;
}

// End a group.

void
Input_arguments::end_group()
{
  if (!this->in_group_)
    gold_fatal(_("Group end without group start"));
  this->in_group_ = false;
}

// Command_line options.

Command_line::Command_line()
{
}

// Process the command line options.  For process_one_option, i is the
// index of argv to process next, and must be an option (that is,
// start with a dash).  The return value is the index of the next
// option to process (i+1 or i+2, or argc to indicate processing is
// done).  no_more_options is set to true if (and when) "--" is seen
// as an option.

int
Command_line::process_one_option(int argc, const char** argv, int i,
                                 bool* no_more_options)
{
  gold_assert(argv[i][0] == '-' && !(*no_more_options));

  // If we are reading "--", then just set no_more_options and return.
  if (argv[i][1] == '-' && argv[i][2] == '\0')
    {
      *no_more_options = true;
      return i + 1;
    }

  int new_i = i;
  options::One_option* option = NULL;
  const char* arg = NULL;

  // First, try to process argv as a long option.
  option = parse_long_option(argc, argv, false, &arg, &new_i);
  if (option)
    {
      option->reader->parse_to_value(argv[i], arg, this, &this->options_);
      return new_i;
    }

  // Now, try to process argv as a short option.  Since several short
  // options can be combined in one argv, we may have to parse a lot
  // until we're done reading this argv.
  int pos_in_argv_i = 1;
  while (new_i == i)
    {
      option = parse_short_option(argc, argv, pos_in_argv_i, &arg, &new_i);
      if (!option)
        break;
      option->reader->parse_to_value(argv[i], arg, this, &this->options_);
      ++pos_in_argv_i;
    }
  if (option)
    return new_i;

  // I guess it's neither a long option nor a short option.
  usage(_("unknown option"), argv[i]);
  return argc;
}


void
Command_line::process(int argc, const char** argv)
{
  bool no_more_options = false;
  int i = 0;
  while (i < argc)
    {
      this->position_options_.copy_from_options(this->options());
      if (no_more_options || argv[i][0] != '-')
        {
          Input_file_argument file(argv[i], false, "", false,
                                   this->position_options_);
          this->inputs_.add_file(file);
          ++i;
        }
      else
        i = process_one_option(argc, argv, i, &no_more_options);
    }

  if (this->inputs_.in_group())
    {
      fprintf(stderr, _("%s: missing group end\n"), program_name);
      usage();
    }

  // Normalize the options and ensure they don't contradict each other.
  this->options_.finalize();
}

} // End namespace gold.