gold/options.h

   1 // options.h -- handle command line options for gold  -*- C++ -*-
   2
   3 // Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 // General_options (from Command_line::options())
  24 //   All the options (a.k.a. command-line flags)
  25 // Input_argument (from Command_line::inputs())
  26 //   The list of input files, including -l options.
  27 // Command_line
  28 //   Everything we get from the command line -- the General_options
  29 //   plus the Input_arguments.
  30 //
  31 // There are also some smaller classes, such as
  32 // Position_dependent_options which hold a subset of General_options
  33 // that change as options are parsed (as opposed to the usual behavior
  34 // of the last instance of that option specified on the commandline wins).
  35
  36 #ifndef GOLD_OPTIONS_H
  37 #define GOLD_OPTIONS_H
  38
  39 #include <cstdlib>
  40 #include <cstring>
  41 #include <list>
  42 #include <string>
  43 #include <vector>
  44
  45 #include "elfcpp.h"
  46 #include "script.h"
  47
  48 namespace gold
  49 {
  50
  51 class Command_line;
  52 class General_options;
  53 class Search_directory;
  54 class Input_file_group;
  55 class Position_dependent_options;
  56 class Target;
  57
  58 // The nested namespace is to contain all the global variables and
  59 // structs that need to be defined in the .h file, but do not need to
  60 // be used outside this class.
  61 namespace options
  62 {
  63 typedef std::vector<Search_directory> Dir_list;
  64 typedef Unordered_set<std::string> String_set;
  65
  66 // These routines convert from a string option to various types.
  67 // Each gives a fatal error if it cannot parse the argument.
  68
  69 extern void
  70 parse_bool(const char* option_name, const char* arg, bool* retval);
  71
  72 extern void
  73 parse_uint(const char* option_name, const char* arg, int* retval);
  74
  75 extern void
  76 parse_uint64(const char* option_name, const char* arg, uint64_t* retval);
  77
  78 extern void
  79 parse_double(const char* option_name, const char* arg, double* retval);
  80
  81 extern void
  82 parse_string(const char* option_name, const char* arg, const char** retval);
  83
  84 extern void
  85 parse_optional_string(const char* option_name, const char* arg,
  86                       const char** retval);
  87
  88 extern void
  89 parse_dirlist(const char* option_name, const char* arg, Dir_list* retval);
  90
  91 extern void
  92 parse_set(const char* option_name, const char* arg, String_set* retval);
  93
  94 extern void
  95 parse_choices(const char* option_name, const char* arg, const char** retval,
  96               const char* choices[], int num_choices);
  97
  98 struct Struct_var;
  99
 100 // Most options have both a shortname (one letter) and a longname.
 101 // This enum controls how many dashes are expected for longname access
 102 // -- shortnames always use one dash.  Most longnames will accept
 103 // either one dash or two; the only difference between ONE_DASH and
 104 // TWO_DASHES is how we print the option in --help.  However, some
 105 // longnames require two dashes, and some require only one.  The
 106 // special value DASH_Z means that the option is preceded by "-z".
 107 enum Dashes
 108 {
 109   ONE_DASH, TWO_DASHES, EXACTLY_ONE_DASH, EXACTLY_TWO_DASHES, DASH_Z
 110 };
 111
 112 // LONGNAME is the long-name of the option with dashes converted to
 113 //    underscores, or else the short-name if the option has no long-name.
 114 //    It is never the empty string.
 115 // DASHES is an instance of the Dashes enum: ONE_DASH, TWO_DASHES, etc.
 116 // SHORTNAME is the short-name of the option, as a char, or '\0' if the
 117 //    option has no short-name.  If the option has no long-name, you
 118 //    should specify the short-name in *both* VARNAME and here.
 119 // DEFAULT_VALUE is the value of the option if not specified on the
 120 //    commandline, as a string.
 121 // HELPSTRING is the descriptive text used with the option via --help
 122 // HELPARG is how you define the argument to the option.
 123 //    --help output is "-shortname HELPARG, --longname HELPARG: HELPSTRING"
 124 //    HELPARG should be NULL iff the option is a bool and takes no arg.
 125 // OPTIONAL_ARG is true if this option takes an optional argument.  An
 126 //    optional argument must be specifid as --OPTION=VALUE, not
 127 //    --OPTION VALUE.
 128 // READER provides parse_to_value, which is a function that will convert
 129 //    a char* argument into the proper type and store it in some variable.
 130 // A One_option struct initializes itself with the global list of options
 131 // at constructor time, so be careful making one of these.
 132 struct One_option
 133 {
 134   std::string longname;
 135   Dashes dashes;
 136   char shortname;
 137   const char* default_value;
 138   const char* helpstring;
 139   const char* helparg;
 140   bool optional_arg;
 141   Struct_var* reader;
 142
 143   One_option(const char* ln, Dashes d, char sn, const char* dv,
 144              const char* hs, const char* ha, bool oa, Struct_var* r)
 145     : longname(ln), dashes(d), shortname(sn), default_value(dv ? dv : ""),
 146       helpstring(hs), helparg(ha), optional_arg(oa), reader(r)
 147   {
 148     // In longname, we convert all underscores to dashes, since GNU
 149     // style uses dashes in option names.  longname is likely to have
 150     // underscores in it because it's also used to declare a C++
 151     // function.
 152     const char* pos = strchr(this->longname.c_str(), '_');
 153     for (; pos; pos = strchr(pos, '_'))
 154       this->longname[pos - this->longname.c_str()] = '-';
 155
 156     // We only register ourselves if our helpstring is not NULL.  This
 157     // is to support the "no-VAR" boolean variables, which we
 158     // conditionally turn on by defining "no-VAR" help text.
 159     if (this->helpstring)
 160       this->register_option();
 161   }
 162
 163   // This option takes an argument iff helparg is not NULL.
 164   bool
 165   takes_argument() const
 166   { return this->helparg != NULL; }
 167
 168   // Whether the argument is optional.
 169   bool
 170   takes_optional_argument() const
 171   { return this->optional_arg; }
 172
 173   // Register this option with the global list of options.
 174   void
 175   register_option();
 176
 177   // Print this option to stdout (used with --help).
 178   void
 179   print() const;
 180 };
 181
 182 // All options have a Struct_##varname that inherits from this and
 183 // actually implements parse_to_value for that option.
 184 struct Struct_var
 185 {
 186   // OPTION: the name of the option as specified on the commandline,
 187   //    including leading dashes, and any text following the option:
 188   //    "-O", "--defsym=mysym=0x1000", etc.
 189   // ARG: the arg associated with this option, or NULL if the option
 190   //    takes no argument: "2", "mysym=0x1000", etc.
 191   // CMDLINE: the global Command_line object.  Used by DEFINE_special.
 192   // OPTIONS: the global General_options object.  Used by DEFINE_special.
 193   virtual void
 194   parse_to_value(const char* option, const char* arg,
 195                  Command_line* cmdline, General_options* options) = 0;
 196   virtual
 197   ~Struct_var()  // To make gcc happy.
 198   { }
 199 };
 200
 201 // This is for "special" options that aren't of any predefined type.
 202 struct Struct_special : public Struct_var
 203 {
 204   // If you change this, change the parse-fn in DEFINE_special as well.
 205   typedef void (General_options::*Parse_function)(const char*, const char*,
 206                                                   Command_line*);
 207   Struct_special(const char* varname, Dashes dashes, char shortname,
 208                  Parse_function parse_function,
 209                  const char* helpstring, const char* helparg)
 210     : option(varname, dashes, shortname, "", helpstring, helparg, false, this),
 211       parse(parse_function)
 212   { }
 213
 214   void parse_to_value(const char* option, const char* arg,
 215                       Command_line* cmdline, General_options* options)
 216   { (options->*(this->parse))(option, arg, cmdline); }
 217
 218   One_option option;
 219   Parse_function parse;
 220 };
 221
 222 }  // End namespace options.
 223
 224
 225 // These are helper macros use by DEFINE_uint64/etc below.
 226 // This macro is used inside the General_options_ class, so defines
 227 // var() and set_var() as General_options methods.  Arguments as are
 228 // for the constructor for One_option.  param_type__ is the same as
 229 // type__ for built-in types, and "const type__ &" otherwise.
 230 #define DEFINE_var(varname__, dashes__, shortname__, default_value__,        \
 231                    default_value_as_string__, helpstring__, helparg__,       \
 232                    optional_arg__, type__, param_type__, parse_fn__)         \
 233  public:                                                                     \
 234   param_type__                                                               \
 235   varname__() const                                                          \
 236   { return this->varname__##_.value; }                                       \
 237                                                                              \
 238   bool                                                                       \
 239   user_set_##varname__() const                                               \
 240   { return this->varname__##_.user_set_via_option; }                         \
 241                                                                              \
 242   void                                                                       \
 243   set_user_set_##varname__()                                                 \
 244   { this->varname__##_.user_set_via_option = true; }                         \
 245                                                                              \
 246  private:                                                                    \
 247   struct Struct_##varname__ : public options::Struct_var                     \
 248   {                                                                          \
 249     Struct_##varname__()                                                     \
 250       : option(#varname__, dashes__, shortname__, default_value_as_string__, \
 251                helpstring__, helparg__, optional_arg__, this),               \
 252         user_set_via_option(false), value(default_value__)                   \
 253     { }                                                                      \
 254                                                                              \
 255     void                                                                     \
 256     parse_to_value(const char* option_name, const char* arg,                 \
 257                    Command_line*, General_options*)                          \
 258     {                                                                        \
 259       parse_fn__(option_name, arg, &this->value);                            \
 260       this->user_set_via_option = true;                                      \
 261     }                                                                        \
 262                                                                              \
 263     options::One_option option;                                              \
 264     bool user_set_via_option;                                                \
 265     type__ value;                                                            \
 266   };                                                                         \
 267   Struct_##varname__ varname__##_;                                           \
 268   void                                                                       \
 269   set_##varname__(param_type__ value)                                        \
 270   { this->varname__##_.value = value; }
 271
 272 // These macros allow for easy addition of a new commandline option.
 273
 274 // If no_helpstring__ is not NULL, then in addition to creating
 275 // VARNAME, we also create an option called no-VARNAME (or, for a -z
 276 // option, noVARNAME).
 277 #define DEFINE_bool(varname__, dashes__, shortname__, default_value__,   \
 278                     helpstring__, no_helpstring__)                       \
 279   DEFINE_var(varname__, dashes__, shortname__, default_value__,          \
 280              default_value__ ? "true" : "false", helpstring__, NULL,     \
 281              false, bool, bool, options::parse_bool)                     \
 282   struct Struct_no_##varname__ : public options::Struct_var              \
 283   {                                                                      \
 284     Struct_no_##varname__() : option((dashes__ == options::DASH_Z        \
 285                                       ? "no" #varname__                  \
 286                                       : "no-" #varname__),               \
 287                                      dashes__, '\0',                     \
 288                                      default_value__ ? "false" : "true", \
 289                                      no_helpstring__, NULL, false, this) \
 290     { }                                                                  \
 291                                                                          \
 292     void                                                                 \
 293     parse_to_value(const char*, const char*,                             \
 294                    Command_line*, General_options* options)              \
 295     { options->set_##varname__(false); }                                 \
 296                                                                          \
 297     options::One_option option;                                          \
 298   };                                                                     \
 299   Struct_no_##varname__ no_##varname__##_initializer_
 300
 301 #define DEFINE_enable(varname__, dashes__, shortname__, default_value__, \
 302                       helpstring__, no_helpstring__)                     \
 303   DEFINE_var(enable_##varname__, dashes__, shortname__, default_value__, \
 304              default_value__ ? "true" : "false", helpstring__, NULL,     \
 305              false, bool, bool, options::parse_bool)                     \
 306   struct Struct_disable_##varname__ : public options::Struct_var         \
 307   {                                                                      \
 308     Struct_disable_##varname__() : option("disable-" #varname__,         \
 309                                      dashes__, '\0',                     \
 310                                      default_value__ ? "false" : "true", \
 311                                      no_helpstring__, NULL, false, this) \
 312     { }                                                                  \
 313                                                                          \
 314     void                                                                 \
 315     parse_to_value(const char*, const char*,                             \
 316                    Command_line*, General_options* options)              \
 317     { options->set_enable_##varname__(false); }                          \
 318                                                                          \
 319     options::One_option option;                                          \
 320   };                                                                     \
 321   Struct_disable_##varname__ disable_##varname__##_initializer_
 322
 323 #define DEFINE_uint(varname__, dashes__, shortname__, default_value__,  \
 324                    helpstring__, helparg__)                             \
 325   DEFINE_var(varname__, dashes__, shortname__, default_value__,         \
 326              #default_value__, helpstring__, helparg__, false,          \
 327              int, int, options::parse_uint)
 328
 329 #define DEFINE_uint64(varname__, dashes__, shortname__, default_value__, \
 330                       helpstring__, helparg__)                           \
 331   DEFINE_var(varname__, dashes__, shortname__, default_value__,          \
 332              #default_value__, helpstring__, helparg__, false,           \
 333              uint64_t, uint64_t, options::parse_uint64)
 334
 335 #define DEFINE_double(varname__, dashes__, shortname__, default_value__, \
 336                       helpstring__, helparg__)                           \
 337   DEFINE_var(varname__, dashes__, shortname__, default_value__,          \
 338              #default_value__, helpstring__, helparg__, false,           \
 339              double, double, options::parse_double)
 340
 341 #define DEFINE_string(varname__, dashes__, shortname__, default_value__, \
 342                       helpstring__, helparg__)                           \
 343   DEFINE_var(varname__, dashes__, shortname__, default_value__,          \
 344              default_value__, helpstring__, helparg__, false,            \
 345              const char*, const char*, options::parse_string)
 346
 347 // This is like DEFINE_string, but we convert each occurrence to a
 348 // Search_directory and store it in a vector.  Thus we also have the
 349 // add_to_VARNAME() method, to append to the vector.
 350 #define DEFINE_dirlist(varname__, dashes__, shortname__,                  \
 351                            helpstring__, helparg__)                       \
 352   DEFINE_var(varname__, dashes__, shortname__, ,                          \
 353              "", helpstring__, helparg__, false, options::Dir_list,       \
 354              const options::Dir_list&, options::parse_dirlist)            \
 355   void                                                                    \
 356   add_to_##varname__(const char* new_value)                               \
 357   { options::parse_dirlist(NULL, new_value, &this->varname__##_.value); } \
 358   void                                                                    \
 359   add_search_directory_to_##varname__(const Search_directory& dir)        \
 360   { this->varname__##_.value.push_back(dir); }
 361
 362 // This is like DEFINE_string, but we store a set of strings.
 363 #define DEFINE_set(varname__, dashes__, shortname__,                      \
 364                    helpstring__, helparg__)                               \
 365   DEFINE_var(varname__, dashes__, shortname__, ,                          \
 366              "", helpstring__, helparg__, false, options::String_set,     \
 367              const options::String_set&, options::parse_set)              \
 368  public:                                                                  \
 369   bool                                                                    \
 370   any_##varname__() const                                                 \
 371   { return !this->varname__##_.value.empty(); }                           \
 372                                                                           \
 373   bool                                                                    \
 374   is_##varname__(const char* symbol) const                                \
 375   {                                                                       \
 376     return (!this->varname__##_.value.empty()                             \
 377             && (this->varname__##_.value.find(std::string(symbol))        \
 378                 != this->varname__##_.value.end()));                      \
 379   }                                                                       \
 380                                                                           \
 381   options::String_set::const_iterator                                     \
 382   varname__##_begin() const                                               \
 383   { return this->varname__##_.value.begin(); }                            \
 384                                                                           \
 385   options::String_set::const_iterator                                     \
 386   varname__##_end() const                                                 \
 387   { return this->varname__##_.value.end(); }
 388
 389 // When you have a list of possible values (expressed as string)
 390 // After helparg__ should come an initializer list, like
 391 //   {"foo", "bar", "baz"}
 392 #define DEFINE_enum(varname__, dashes__, shortname__, default_value__,   \
 393                     helpstring__, helparg__, ...)                        \
 394   DEFINE_var(varname__, dashes__, shortname__, default_value__,          \
 395              default_value__, helpstring__, helparg__, false,            \
 396              const char*, const char*, parse_choices_##varname__)        \
 397  private:                                                                \
 398   static void parse_choices_##varname__(const char* option_name,         \
 399                                         const char* arg,                 \
 400                                         const char** retval) {           \
 401     const char* choices[] = __VA_ARGS__;                                 \
 402     options::parse_choices(option_name, arg, retval,                     \
 403                            choices, sizeof(choices) / sizeof(*choices)); \
 404   }
 405
 406 // This is like DEFINE_bool, but VARNAME is the name of a different
 407 // option.  This option becomes an alias for that one.  INVERT is true
 408 // if this option is an inversion of the other one.
 409 #define DEFINE_bool_alias(option__, varname__, dashes__, shortname__,   \
 410                           helpstring__, no_helpstring__, invert__)      \
 411  private:                                                               \
 412   struct Struct_##option__ : public options::Struct_var                 \
 413   {                                                                     \
 414     Struct_##option__()                                                 \
 415       : option(#option__, dashes__, shortname__, "", helpstring__,      \
 416                NULL, false, this)                                       \
 417     { }                                                                 \
 418                                                                         \
 419     void                                                                \
 420     parse_to_value(const char*, const char*,                            \
 421                    Command_line*, General_options* options)             \
 422     {                                                                   \
 423       options->set_##varname__(!invert__);                              \
 424       options->set_user_set_##varname__();                              \
 425     }                                                                   \
 426                                                                         \
 427     options::One_option option;                                         \
 428   };                                                                    \
 429   Struct_##option__ option__##_;                                        \
 430                                                                         \
 431   struct Struct_no_##option__ : public options::Struct_var              \
 432   {                                                                     \
 433     Struct_no_##option__()                                              \
 434       : option((dashes__ == options::DASH_Z                             \
 435                 ? "no" #option__                                        \
 436                 : "no-" #option__),                                     \
 437                dashes__, '\0', "", no_helpstring__,                     \
 438                NULL, false, this)                                       \
 439     { }                                                                 \
 440                                                                         \
 441     void                                                                \
 442     parse_to_value(const char*, const char*,                            \
 443                    Command_line*, General_options* options)             \
 444     {                                                                   \
 445       options->set_##varname__(invert__);                               \
 446       options->set_user_set_##varname__();                              \
 447     }                                                                   \
 448                                                                         \
 449     options::One_option option;                                         \
 450   };                                                                    \
 451   Struct_no_##option__ no_##option__##_initializer_
 452
 453 // This is used for non-standard flags.  It defines no functions; it
 454 // just calls General_options::parse_VARNAME whenever the flag is
 455 // seen.  We declare parse_VARNAME as a static member of
 456 // General_options; you are responsible for defining it there.
 457 // helparg__ should be NULL iff this special-option is a boolean.
 458 #define DEFINE_special(varname__, dashes__, shortname__,                \
 459                        helpstring__, helparg__)                         \
 460  private:                                                               \
 461   void parse_##varname__(const char* option, const char* arg,           \
 462                          Command_line* inputs);                         \
 463   struct Struct_##varname__ : public options::Struct_special            \
 464   {                                                                     \
 465     Struct_##varname__()                                                \
 466       : options::Struct_special(#varname__, dashes__, shortname__,      \
 467                                 &General_options::parse_##varname__,    \
 468                                 helpstring__, helparg__)                \
 469     { }                                                                 \
 470   };                                                                    \
 471   Struct_##varname__ varname__##_initializer_
 472
 473 // An option that takes an optional string argument.  If the option is
 474 // used with no argument, the value will be the default, and
 475 // user_set_via_option will be true.
 476 #define DEFINE_optional_string(varname__, dashes__, shortname__,        \
 477                                default_value__,                         \
 478                                helpstring__, helparg__)                 \
 479   DEFINE_var(varname__, dashes__, shortname__, default_value__,         \
 480              default_value__, helpstring__, helparg__, true,            \
 481              const char*, const char*, options::parse_optional_string)
 482
 483 // A directory to search.  For each directory we record whether it is
 484 // in the sysroot.  We need to know this so that, if a linker script
 485 // is found within the sysroot, we will apply the sysroot to any files
 486 // named by that script.
 487
 488 class Search_directory
 489 {
 490  public:
 491   // We need a default constructor because we put this in a
 492   // std::vector.
 493   Search_directory()
 494     : name_(NULL), put_in_sysroot_(false), is_in_sysroot_(false)
 495   { }
 496
 497   // This is the usual constructor.
 498   Search_directory(const char* name, bool put_in_sysroot)
 499     : name_(name), put_in_sysroot_(put_in_sysroot), is_in_sysroot_(false)
 500   {
 501     if (this->name_.empty())
 502       this->name_ = ".";
 503   }
 504
 505   // This is called if we have a sysroot.  The sysroot is prefixed to
 506   // any entries for which put_in_sysroot_ is true.  is_in_sysroot_ is
 507   // set to true for any enries which are in the sysroot (this will
 508   // naturally include any entries for which put_in_sysroot_ is true).
 509   // SYSROOT is the sysroot, CANONICAL_SYSROOT is the result of
 510   // passing SYSROOT to lrealpath.
 511   void
 512   add_sysroot(const char* sysroot, const char* canonical_sysroot);
 513
 514   // Get the directory name.
 515   const std::string&
 516   name() const
 517   { return this->name_; }
 518
 519   // Return whether this directory is in the sysroot.
 520   bool
 521   is_in_sysroot() const
 522   { return this->is_in_sysroot_; }
 523
 524  private:
 525   std::string name_;
 526   bool put_in_sysroot_;
 527   bool is_in_sysroot_;
 528 };
 529
 530 class General_options
 531 {
 532  private:
 533   // NOTE: For every option that you add here, also consider if you
 534   // should add it to Position_dependent_options.
 535   DEFINE_special(help, options::TWO_DASHES, '\0',
 536                  N_("Report usage information"), NULL);
 537   DEFINE_special(version, options::TWO_DASHES, 'v',
 538                  N_("Report version information"), NULL);
 539   DEFINE_special(V, options::EXACTLY_ONE_DASH, '\0',
 540                  N_("Report version and target information"), NULL);
 541
 542   // These options are sorted approximately so that for each letter in
 543   // the alphabet, we show the option whose shortname is that letter
 544   // (if any) and then every longname that starts with that letter (in
 545   // alphabetical order).  For both, lowercase sorts before uppercase.
 546   // The -z options come last.
 547
 548   DEFINE_bool(allow_shlib_undefined, options::TWO_DASHES, '\0', false,
 549               N_("Allow unresolved references in shared libraries"),
 550               N_("Do not allow unresolved references in shared libraries"));
 551
 552   DEFINE_bool(as_needed, options::TWO_DASHES, '\0', false,
 553               N_("Only set DT_NEEDED for dynamic libs if used"),
 554               N_("Always DT_NEEDED for dynamic libs"));
 555
 556   // This should really be an "enum", but it's too easy for folks to
 557   // forget to update the list as they add new targets.  So we just
 558   // accept any string.  We'll fail later (when the string is parsed),
 559   // if the target isn't actually supported.
 560   DEFINE_string(format, options::TWO_DASHES, 'b', "elf",
 561                 N_("Set input format"), ("[elf,binary]"));
 562
 563   DEFINE_bool(Bdynamic, options::ONE_DASH, '\0', true,
 564               N_("-l searches for shared libraries"), NULL);
 565   DEFINE_bool_alias(Bstatic, Bdynamic, options::ONE_DASH, '\0',
 566                     N_("-l does not search for shared libraries"), NULL,
 567                     true);
 568
 569   DEFINE_bool(Bsymbolic, options::ONE_DASH, '\0', false,
 570               N_("Bind defined symbols locally"), NULL);
 571
 572   DEFINE_bool(Bsymbolic_functions, options::ONE_DASH, '\0', false,
 573               N_("Bind defined function symbols locally"), NULL);
 574
 575   DEFINE_optional_string(build_id, options::TWO_DASHES, '\0', "sha1",
 576                          N_("Generate build ID note"),
 577                          N_("[=STYLE]"));
 578
 579   DEFINE_bool(check_sections, options::TWO_DASHES, '\0', true,
 580               N_("Check segment addresses for overlaps (default)"),
 581               N_("Do not check segment addresses for overlaps"));
 582
 583 #ifdef HAVE_ZLIB_H
 584   DEFINE_enum(compress_debug_sections, options::TWO_DASHES, '\0', "none",
 585               N_("Compress .debug_* sections in the output file"),
 586               ("[none,zlib]"),
 587               {"none", "zlib"});
 588 #else
 589   DEFINE_enum(compress_debug_sections, options::TWO_DASHES, '\0', "none",
 590               N_("Compress .debug_* sections in the output file"),
 591               N_("[none]"),
 592               {"none"});
 593 #endif
 594
 595   DEFINE_bool(define_common, options::TWO_DASHES, 'd', false,
 596               N_("Define common symbols"),
 597               N_("Do not define common symbols"));
 598   DEFINE_bool(dc, options::ONE_DASH, '\0', false,
 599               N_("Alias for -d"), NULL);
 600   DEFINE_bool(dp, options::ONE_DASH, '\0', false,
 601               N_("Alias for -d"), NULL);
 602
 603   DEFINE_string(debug, options::TWO_DASHES, '\0', "",
 604                 N_("Turn on debugging"),
 605                 N_("[all,files,script,task][,...]"));
 606
 607   DEFINE_special(defsym, options::TWO_DASHES, '\0',
 608                  N_("Define a symbol"), N_("SYMBOL=EXPRESSION"));
 609
 610   DEFINE_optional_string(demangle, options::TWO_DASHES, '\0', NULL,
 611                          N_("Demangle C++ symbols in log messages"),
 612                          N_("[=STYLE]"));
 613
 614   DEFINE_bool(no_demangle, options::TWO_DASHES, '\0', false,
 615               N_("Do not demangle C++ symbols in log messages"),
 616               NULL);
 617
 618   DEFINE_bool(detect_odr_violations, options::TWO_DASHES, '\0', false,
 619               N_("Try to detect violations of the One Definition Rule"),
 620               NULL);
 621
 622   DEFINE_string(entry, options::TWO_DASHES, 'e', NULL,
 623                 N_("Set program start address"), N_("ADDRESS"));
 624
 625   DEFINE_bool(export_dynamic, options::TWO_DASHES, 'E', false,
 626               N_("Export all dynamic symbols"), NULL);
 627
 628   DEFINE_bool(eh_frame_hdr, options::TWO_DASHES, '\0', false,
 629               N_("Create exception frame header"), NULL);
 630
 631   DEFINE_bool(fatal_warnings, options::TWO_DASHES, '\0', false,
 632               N_("Treat warnings as errors"),
 633               N_("Do not treat warnings as errors"));
 634
 635   DEFINE_string(soname, options::ONE_DASH, 'h', NULL,
 636                 N_("Set shared library name"), N_("FILENAME"));
 637
 638   DEFINE_double(hash_bucket_empty_fraction, options::TWO_DASHES, '\0', 0.0,
 639                 N_("Min fraction of empty buckets in dynamic hash"),
 640                 N_("FRACTION"));
 641
 642   DEFINE_enum(hash_style, options::TWO_DASHES, '\0', "sysv",
 643               N_("Dynamic hash style"), N_("[sysv,gnu,both]"),
 644               {"sysv", "gnu", "both"});
 645
 646   DEFINE_string(dynamic_linker, options::TWO_DASHES, 'I', NULL,
 647                 N_("Set dynamic linker path"), N_("PROGRAM"));
 648
 649   DEFINE_special(just_symbols, options::TWO_DASHES, '\0',
 650                  N_("Read only symbol values from FILE"), N_("FILE"));
 651
 652   DEFINE_special(library, options::TWO_DASHES, 'l',
 653                  N_("Search for library LIBNAME"), N_("LIBNAME"));
 654
 655   DEFINE_dirlist(library_path, options::TWO_DASHES, 'L',
 656                  N_("Add directory to search path"), N_("DIR"));
 657
 658   DEFINE_string(m, options::EXACTLY_ONE_DASH, 'm', "",
 659                 N_("Ignored for compatibility"), N_("EMULATION"));
 660
 661   DEFINE_bool(print_map, options::TWO_DASHES, 'M', false,
 662               N_("Write map file on standard output"), NULL);
 663   DEFINE_string(Map, options::ONE_DASH, '\0', NULL, N_("Write map file"),
 664                 N_("MAPFILENAME"));
 665
 666   DEFINE_bool(nmagic, options::TWO_DASHES, 'n', false,
 667               N_("Do not page align data"), NULL);
 668   DEFINE_bool(omagic, options::EXACTLY_TWO_DASHES, 'N', false,
 669               N_("Do not page align data, do not make text readonly"),
 670               N_("Page align data, make text readonly"));
 671
 672   DEFINE_enable(new_dtags, options::EXACTLY_TWO_DASHES, '\0', false,
 673                 N_("Enable use of DT_RUNPATH and DT_FLAGS"),
 674                 N_("Disable use of DT_RUNPATH and DT_FLAGS"));
 675
 676   DEFINE_bool(noinhibit_exec, options::TWO_DASHES, '\0', false,
 677               N_("Create an output file even if errors occur"), NULL);
 678
 679   DEFINE_bool_alias(no_undefined, defs, options::TWO_DASHES, '\0',
 680                     N_("Report undefined symbols (even with --shared)"),
 681                     NULL, false);
 682
 683   DEFINE_string(output, options::TWO_DASHES, 'o', "a.out",
 684                 N_("Set output file name"), N_("FILE"));
 685
 686   DEFINE_uint(optimize, options::EXACTLY_ONE_DASH, 'O', 0,
 687               N_("Optimize output file size"), N_("LEVEL"));
 688
 689   DEFINE_string(oformat, options::EXACTLY_TWO_DASHES, '\0', "elf",
 690                 N_("Set output format"), N_("[binary]"));
 691
 692   DEFINE_bool(preread_archive_symbols, options::TWO_DASHES, '\0', false,
 693               N_("Preread archive symbols when multi-threaded"), NULL);
 694   DEFINE_string(print_symbol_counts, options::TWO_DASHES, '\0', NULL,
 695                 N_("Print symbols defined and used for each input"),
 696                 N_("FILENAME"));
 697
 698   DEFINE_bool(Qy, options::EXACTLY_ONE_DASH, '\0', false,
 699               N_("Ignored for SVR4 compatibility"), NULL);
 700
 701   DEFINE_bool(emit_relocs, options::TWO_DASHES, 'q', false,
 702               N_("Generate relocations in output"), NULL);
 703
 704   DEFINE_bool(relocatable, options::EXACTLY_ONE_DASH, 'r', false,
 705               N_("Generate relocatable output"), NULL);
 706
 707   DEFINE_bool(relax, options::TWO_DASHES, '\0', false,
 708               N_("Relax branches on certain targets"), NULL);
 709
 710   // -R really means -rpath, but can mean --just-symbols for
 711   // compatibility with GNU ld.  -rpath is always -rpath, so we list
 712   // it separately.
 713   DEFINE_special(R, options::EXACTLY_ONE_DASH, 'R',
 714                  N_("Add DIR to runtime search path"), N_("DIR"));
 715
 716   DEFINE_dirlist(rpath, options::ONE_DASH, '\0',
 717                  N_("Add DIR to runtime search path"), N_("DIR"));
 718
 719   DEFINE_dirlist(rpath_link, options::TWO_DASHES, '\0',
 720                  N_("Add DIR to link time shared library search path"),
 721                  N_("DIR"));
 722
 723   DEFINE_bool(strip_all, options::TWO_DASHES, 's', false,
 724               N_("Strip all symbols"), NULL);
 725   DEFINE_bool(strip_debug, options::TWO_DASHES, 'S', false,
 726               N_("Strip debugging information"), NULL);
 727   DEFINE_bool(strip_debug_non_line, options::TWO_DASHES, '\0', false,
 728               N_("Emit only debug line number information"), NULL);
 729   DEFINE_bool(strip_debug_gdb, options::TWO_DASHES, '\0', false,
 730               N_("Strip debug symbols that are unused by gdb "
 731                  "(at least versions <= 6.7)"), NULL);
 732
 733   DEFINE_bool(shared, options::ONE_DASH, '\0', false,
 734               N_("Generate shared library"), NULL);
 735
 736   // This is not actually special in any way, but I need to give it
 737   // a non-standard accessor-function name because 'static' is a keyword.
 738   DEFINE_special(static, options::ONE_DASH, '\0',
 739                  N_("Do not link against shared libraries"), NULL);
 740
 741   DEFINE_bool(stats, options::TWO_DASHES, '\0', false,
 742               N_("Print resource usage statistics"), NULL);
 743
 744   DEFINE_string(sysroot, options::TWO_DASHES, '\0', "",
 745                 N_("Set target system root directory"), N_("DIR"));
 746
 747   DEFINE_bool(trace, options::TWO_DASHES, 't', false,
 748               N_("Print the name of each input file"), NULL);
 749
 750   DEFINE_special(script, options::TWO_DASHES, 'T',
 751                  N_("Read linker script"), N_("FILE"));
 752
 753   DEFINE_bool(threads, options::TWO_DASHES, '\0', false,
 754               N_("Run the linker multi-threaded"),
 755               N_("Do not run the linker multi-threaded"));
 756   DEFINE_uint(thread_count, options::TWO_DASHES, '\0', 0,
 757               N_("Number of threads to use"), N_("COUNT"));
 758   DEFINE_uint(thread_count_initial, options::TWO_DASHES, '\0', 0,
 759               N_("Number of threads to use in initial pass"), N_("COUNT"));
 760   DEFINE_uint(thread_count_middle, options::TWO_DASHES, '\0', 0,
 761               N_("Number of threads to use in middle pass"), N_("COUNT"));
 762   DEFINE_uint(thread_count_final, options::TWO_DASHES, '\0', 0,
 763               N_("Number of threads to use in final pass"), N_("COUNT"));
 764
 765   DEFINE_uint64(Tbss, options::ONE_DASH, '\0', -1U,
 766                 N_("Set the address of the bss segment"), N_("ADDRESS"));
 767   DEFINE_uint64(Tdata, options::ONE_DASH, '\0', -1U,
 768                 N_("Set the address of the data segment"), N_("ADDRESS"));
 769   DEFINE_uint64(Ttext, options::ONE_DASH, '\0', -1U,
 770                 N_("Set the address of the text segment"), N_("ADDRESS"));
 771
 772   DEFINE_set(undefined, options::TWO_DASHES, 'u',
 773              N_("Create undefined reference to SYMBOL"), N_("SYMBOL"));
 774
 775   DEFINE_bool(verbose, options::TWO_DASHES, '\0', false,
 776               N_("Synonym for --debug=files"), NULL);
 777
 778   DEFINE_special(version_script, options::TWO_DASHES, '\0',
 779                  N_("Read version script"), N_("FILE"));
 780
 781   DEFINE_bool(whole_archive, options::TWO_DASHES, '\0', false,
 782               N_("Include all archive contents"),
 783               N_("Include only needed archive contents"));
 784
 785   DEFINE_set(wrap, options::TWO_DASHES, '\0',
 786              N_("Use wrapper functions for SYMBOL"), N_("SYMBOL"));
 787
 788   DEFINE_set(trace_symbol, options::TWO_DASHES, 'y',
 789              N_("Trace references to symbol"), N_("SYMBOL"));
 790
 791   DEFINE_string(Y, options::EXACTLY_ONE_DASH, 'Y', "",
 792                 N_("Default search path for Solaris compatibility"),
 793                 N_("PATH"));
 794
 795   DEFINE_special(start_group, options::TWO_DASHES, '(',
 796                  N_("Start a library search group"), NULL);
 797   DEFINE_special(end_group, options::TWO_DASHES, ')',
 798                  N_("End a library search group"), NULL);
 799
 800   // The -z options.
 801
 802   DEFINE_bool(combreloc, options::DASH_Z, '\0', true,
 803               N_("Sort dynamic relocs"),
 804               N_("Do not sort dynamic relocs"));
 805   DEFINE_uint64(common_page_size, options::DASH_Z, '\0', 0,
 806                 N_("Set common page size to SIZE"), N_("SIZE"));
 807   DEFINE_bool(defs, options::DASH_Z, '\0', false,
 808               N_("Report undefined symbols (even with --shared)"),
 809               NULL);
 810   DEFINE_bool(execstack, options::DASH_Z, '\0', false,
 811               N_("Mark output as requiring executable stack"), NULL);
 812   DEFINE_uint64(max_page_size, options::DASH_Z, '\0', 0,
 813                 N_("Set maximum page size to SIZE"), N_("SIZE"));
 814   DEFINE_bool(noexecstack, options::DASH_Z, '\0', false,
 815               N_("Mark output as not requiring executable stack"), NULL);
 816   DEFINE_bool(initfirst, options::DASH_Z, '\0', false,
 817               N_("Mark DSO to be initialized first at runtime"),
 818               NULL);
 819   DEFINE_bool(interpose, options::DASH_Z, '\0', false,
 820               N_("Mark object to interpose all DSOs but executable"),
 821               NULL);
 822   DEFINE_bool(loadfltr, options::DASH_Z, '\0', false,
 823               N_("Mark object requiring immediate process"),
 824               NULL);
 825   DEFINE_bool(nodefaultlib, options::DASH_Z, '\0', false,
 826               N_("Mark object not to use default search paths"),
 827               NULL);
 828   DEFINE_bool(nodelete, options::DASH_Z, '\0', false,
 829               N_("Mark DSO non-deletable at runtime"),
 830               NULL);
 831   DEFINE_bool(nodlopen, options::DASH_Z, '\0', false,
 832               N_("Mark DSO not available to dlopen"),
 833               NULL);
 834   DEFINE_bool(nodump, options::DASH_Z, '\0', false,
 835               N_("Mark DSO not available to dldump"),
 836               NULL);
 837   DEFINE_bool(relro, options::DASH_Z, '\0', false,
 838               N_("Where possible mark variables read-only after relocation"),
 839               N_("Don't mark variables read-only after relocation"));
 840
 841  public:
 842   typedef options::Dir_list Dir_list;
 843
 844   General_options();
 845
 846   // Does post-processing on flags, making sure they all have
 847   // non-conflicting values.  Also converts some flags from their
 848   // "standard" types (string, etc), to another type (enum, DirList),
 849   // which can be accessed via a separate method.  Dies if it notices
 850   // any problems.
 851   void finalize();
 852
 853   // The macro defines output() (based on --output), but that's a
 854   // generic name.  Provide this alternative name, which is clearer.
 855   const char*
 856   output_file_name() const
 857   { return this->output(); }
 858
 859   // This is not defined via a flag, but combines flags to say whether
 860   // the output is position-independent or not.
 861   bool
 862   output_is_position_independent() const
 863   { return this->shared(); }
 864
 865   // This would normally be static(), and defined automatically, but
 866   // since static is a keyword, we need to come up with our own name.
 867   bool
 868   is_static() const
 869   { return static_; }
 870
 871   // In addition to getting the input and output formats as a string
 872   // (via format() and oformat()), we also give access as an enum.
 873   enum Object_format
 874   {
 875     // Ordinary ELF.
 876     OBJECT_FORMAT_ELF,
 877     // Straight binary format.
 878     OBJECT_FORMAT_BINARY
 879   };
 880
 881   // Note: these functions are not very fast.
 882   Object_format format_enum() const;
 883   Object_format oformat_enum() const;
 884
 885   // These are the best way to get access to the execstack state,
 886   // not execstack() and noexecstack() which are hard to use properly.
 887   bool
 888   is_execstack_set() const
 889   { return this->execstack_status_ != EXECSTACK_FROM_INPUT; }
 890
 891   bool
 892   is_stack_executable() const
 893   { return this->execstack_status_ == EXECSTACK_YES; }
 894
 895   // The --demangle option takes an optional string, and there is also
 896   // a --no-demangle option.  This is the best way to decide whether
 897   // to demangle or not.
 898   bool
 899   do_demangle() const
 900   { return this->do_demangle_; }
 901
 902  private:
 903   // Don't copy this structure.
 904   General_options(const General_options&);
 905   General_options& operator=(const General_options&);
 906
 907   // Whether to mark the stack as executable.
 908   enum Execstack
 909   {
 910     // Not set on command line.
 911     EXECSTACK_FROM_INPUT,
 912     // Mark the stack as executable (-z execstack).
 913     EXECSTACK_YES,
 914     // Mark the stack as not executable (-z noexecstack).
 915     EXECSTACK_NO
 916   };
 917
 918   void
 919   set_execstack_status(Execstack value)
 920   { this->execstack_status_ = value; }
 921
 922   void
 923   set_do_demangle(bool value)
 924   { this->do_demangle_ = value; }
 925
 926   void
 927   set_static(bool value)
 928   { static_ = value; }
 929
 930   // These are called by finalize() to set up the search-path correctly.
 931   void
 932   add_to_library_path_with_sysroot(const char* arg)
 933   { this->add_search_directory_to_library_path(Search_directory(arg, true)); }
 934
 935   // Apply any sysroot to the directory lists.
 936   void
 937   add_sysroot();
 938
 939   // Whether to mark the stack as executable.
 940   Execstack execstack_status_;
 941   // Whether to do a static link.
 942   bool static_;
 943   // Whether to do demangling.
 944   bool do_demangle_;
 945 };
 946
 947 // The position-dependent options.  We use this to store the state of
 948 // the commandline at a particular point in parsing for later
 949 // reference.  For instance, if we see "ld --whole-archive foo.a
 950 // --no-whole-archive," we want to store the whole-archive option with
 951 // foo.a, so when the time comes to parse foo.a we know we should do
 952 // it in whole-archive mode.  We could store all of General_options,
 953 // but that's big, so we just pick the subset of flags that actually
 954 // change in a position-dependent way.
 955
 956 #define DEFINE_posdep(varname__, type__)        \
 957  public:                                        \
 958   type__                                        \
 959   varname__() const                             \
 960   { return this->varname__##_; }                \
 961                                                 \
 962   void                                          \
 963   set_##varname__(type__ value)                 \
 964   { this->varname__##_ = value; }               \
 965  private:                                       \
 966   type__ varname__##_
 967
 968 class Position_dependent_options
 969 {
 970  public:
 971   Position_dependent_options(const General_options& options
 972                              = Position_dependent_options::default_options_)
 973   { copy_from_options(options); }
 974
 975   void copy_from_options(const General_options& options)
 976   {
 977     this->set_as_needed(options.as_needed());
 978     this->set_Bdynamic(options.Bdynamic());
 979     this->set_format_enum(options.format_enum());
 980     this->set_whole_archive(options.whole_archive());
 981   }
 982
 983   DEFINE_posdep(as_needed, bool);
 984   DEFINE_posdep(Bdynamic, bool);
 985   DEFINE_posdep(format_enum, General_options::Object_format);
 986   DEFINE_posdep(whole_archive, bool);
 987
 988  private:
 989   // This is a General_options with everything set to its default
 990   // value.  A Position_dependent_options created with no argument
 991   // will take its values from here.
 992   static General_options default_options_;
 993 };
 994
 995
 996 // A single file or library argument from the command line.
 997
 998 class Input_file_argument
 999 {
1000  public:
1001   // name: file name or library name
1002   // is_lib: true if name is a library name: that is, emits the leading
1003   //         "lib" and trailing ".so"/".a" from the name
1004   // extra_search_path: an extra directory to look for the file, prior
1005   //         to checking the normal library search path.  If this is "",
1006   //         then no extra directory is added.
1007   // just_symbols: whether this file only defines symbols.
1008   // options: The position dependent options at this point in the
1009   //         command line, such as --whole-archive.
1010   Input_file_argument()
1011     : name_(), is_lib_(false), extra_search_path_(""), just_symbols_(false),
1012       options_()
1013   { }
1014
1015   Input_file_argument(const char* name, bool is_lib,
1016                       const char* extra_search_path,
1017                       bool just_symbols,
1018                       const Position_dependent_options& options)
1019     : name_(name), is_lib_(is_lib), extra_search_path_(extra_search_path),
1020       just_symbols_(just_symbols), options_(options)
1021   { }
1022
1023   // You can also pass in a General_options instance instead of a
1024   // Position_dependent_options.  In that case, we extract the
1025   // position-independent vars from the General_options and only store
1026   // those.
1027   Input_file_argument(const char* name, bool is_lib,
1028                       const char* extra_search_path,
1029                       bool just_symbols,
1030                       const General_options& options)
1031     : name_(name), is_lib_(is_lib), extra_search_path_(extra_search_path),
1032       just_symbols_(just_symbols), options_(options)
1033   { }
1034
1035   const char*
1036   name() const
1037   { return this->name_.c_str(); }
1038
1039   const Position_dependent_options&
1040   options() const
1041   { return this->options_; }
1042
1043   bool
1044   is_lib() const
1045   { return this->is_lib_; }
1046
1047   const char*
1048   extra_search_path() const
1049   {
1050     return (this->extra_search_path_.empty()
1051             ? NULL
1052             : this->extra_search_path_.c_str());
1053   }
1054
1055   // Return whether we should only read symbols from this file.
1056   bool
1057   just_symbols() const
1058   { return this->just_symbols_; }
1059
1060   // Return whether this file may require a search using the -L
1061   // options.
1062   bool
1063   may_need_search() const
1064   { return this->is_lib_ || !this->extra_search_path_.empty(); }
1065
1066  private:
1067   // We use std::string, not const char*, here for convenience when
1068   // using script files, so that we do not have to preserve the string
1069   // in that case.
1070   std::string name_;
1071   bool is_lib_;
1072   std::string extra_search_path_;
1073   bool just_symbols_;
1074   Position_dependent_options options_;
1075 };
1076
1077 // A file or library, or a group, from the command line.
1078
1079 class Input_argument
1080 {
1081  public:
1082   // Create a file or library argument.
1083   explicit Input_argument(Input_file_argument file)
1084     : is_file_(true), file_(file), group_(NULL)
1085   { }
1086
1087   // Create a group argument.
1088   explicit Input_argument(Input_file_group* group)
1089     : is_file_(false), group_(group)
1090   { }
1091
1092   // Return whether this is a file.
1093   bool
1094   is_file() const
1095   { return this->is_file_; }
1096
1097   // Return whether this is a group.
1098   bool
1099   is_group() const
1100   { return !this->is_file_; }
1101
1102   // Return the information about the file.
1103   const Input_file_argument&
1104   file() const
1105   {
1106     gold_assert(this->is_file_);
1107     return this->file_;
1108   }
1109
1110   // Return the information about the group.
1111   const Input_file_group*
1112   group() const
1113   {
1114     gold_assert(!this->is_file_);
1115     return this->group_;
1116   }
1117
1118   Input_file_group*
1119   group()
1120   {
1121     gold_assert(!this->is_file_);
1122     return this->group_;
1123   }
1124
1125  private:
1126   bool is_file_;
1127   Input_file_argument file_;
1128   Input_file_group* group_;
1129 };
1130
1131 // A group from the command line.  This is a set of arguments within
1132 // --start-group ... --end-group.
1133
1134 class Input_file_group
1135 {
1136  public:
1137   typedef std::vector<Input_argument> Files;
1138   typedef Files::const_iterator const_iterator;
1139
1140   Input_file_group()
1141     : files_()
1142   { }
1143
1144   // Add a file to the end of the group.
1145   void
1146   add_file(const Input_file_argument& arg)
1147   { this->files_.push_back(Input_argument(arg)); }
1148
1149   // Iterators to iterate over the group contents.
1150
1151   const_iterator
1152   begin() const
1153   { return this->files_.begin(); }
1154
1155   const_iterator
1156   end() const
1157   { return this->files_.end(); }
1158
1159  private:
1160   Files files_;
1161 };
1162
1163 // A list of files from the command line or a script.
1164
1165 class Input_arguments
1166 {
1167  public:
1168   typedef std::vector<Input_argument> Input_argument_list;
1169   typedef Input_argument_list::const_iterator const_iterator;
1170
1171   Input_arguments()
1172     : input_argument_list_(), in_group_(false)
1173   { }
1174
1175   // Add a file.
1176   void
1177   add_file(const Input_file_argument& arg);
1178
1179   // Start a group (the --start-group option).
1180   void
1181   start_group();
1182
1183   // End a group (the --end-group option).
1184   void
1185   end_group();
1186
1187   // Return whether we are currently in a group.
1188   bool
1189   in_group() const
1190   { return this->in_group_; }
1191
1192   // The number of entries in the list.
1193   int
1194   size() const
1195   { return this->input_argument_list_.size(); }
1196
1197   // Iterators to iterate over the list of input files.
1198
1199   const_iterator
1200   begin() const
1201   { return this->input_argument_list_.begin(); }
1202
1203   const_iterator
1204   end() const
1205   { return this->input_argument_list_.end(); }
1206
1207   // Return whether the list is empty.
1208   bool
1209   empty() const
1210   { return this->input_argument_list_.empty(); }
1211
1212  private:
1213   Input_argument_list input_argument_list_;
1214   bool in_group_;
1215 };
1216
1217
1218 // All the information read from the command line.  These are held in
1219 // three separate structs: one to hold the options (--foo), one to
1220 // hold the filenames listed on the commandline, and one to hold
1221 // linker script information.  This third is not a subset of the other
1222 // two because linker scripts can be specified either as options (via
1223 // -T) or as a file.
1224
1225 class Command_line
1226 {
1227  public:
1228   typedef Input_arguments::const_iterator const_iterator;
1229
1230   Command_line();
1231
1232   // Process the command line options.  This will exit with an
1233   // appropriate error message if an unrecognized option is seen.
1234   void
1235   process(int argc, const char** argv);
1236
1237   // Process one command-line option.  This takes the index of argv to
1238   // process, and returns the index for the next option.  no_more_options
1239   // is set to true if argv[i] is "--".
1240   int
1241   process_one_option(int argc, const char** argv, int i,
1242                      bool* no_more_options);
1243
1244   // Get the general options.
1245   const General_options&
1246   options() const
1247   { return this->options_; }
1248
1249   // Get the position dependent options.
1250   const Position_dependent_options&
1251   position_dependent_options() const
1252   { return this->position_options_; }
1253
1254   // Get the linker-script options.
1255   Script_options&
1256   script_options()
1257   { return this->script_options_; }
1258
1259   // Get the version-script options: a convenience routine.
1260   const Version_script_info&
1261   version_script() const
1262   { return *this->script_options_.version_script_info(); }
1263
1264   // Get the input files.
1265   Input_arguments&
1266   inputs()
1267   { return this->inputs_; }
1268
1269   // The number of input files.
1270   int
1271   number_of_input_files() const
1272   { return this->inputs_.size(); }
1273
1274   // Iterators to iterate over the list of input files.
1275
1276   const_iterator
1277   begin() const
1278   { return this->inputs_.begin(); }
1279
1280   const_iterator
1281   end() const
1282   { return this->inputs_.end(); }
1283
1284  private:
1285   Command_line(const Command_line&);
1286   Command_line& operator=(const Command_line&);
1287
1288   General_options options_;
1289   Position_dependent_options position_options_;
1290   Script_options script_options_;
1291   Input_arguments inputs_;
1292 };
1293
1294 } // End namespace gold.
1295
1296 #endif // !defined(GOLD_OPTIONS_H)