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// options.h -- handle command line options for gold  -*- C++ -*-

// Copyright 2006, 2007, 2008, 2009, 2010 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.

// General_options (from Command_line::options())

//   All the options (a.k.a. command-line flags)

// Input_argument (from Command_line::inputs())

//   The list of input files, including -l options.

// Command_line

//   Everything we get from the command line -- the General_options

//   plus the Input_arguments.

//

// There are also some smaller classes, such as

// Position_dependent_options which hold a subset of General_options

// that change as options are parsed (as opposed to the usual behavior

// of the last instance of that option specified on the commandline wins).

#ifndef GOLD_OPTIONS_H

#define GOLD_OPTIONS_H

#include <cstdlib>

#include <cstring>

#include <list>

#include <map>

#include <string>

#include <vector>

#include "elfcpp.h"

#include "script.h"

namespace gold

{

class Command_line;

class General_options;

class Search_directory;

class Input_file_group;

class Input_file_lib;

class Position_dependent_options;

class Target;

class Plugin_manager;

class Script_info;

// Incremental build action for a specific file, as selected by the user.

enum Incremental_disposition

{

  // Determine the status from the timestamp (default).

  INCREMENTAL_CHECK,

  // Assume the file changed from the previous build.

  INCREMENTAL_CHANGED,

  // Assume the file didn't change from the previous build.

  INCREMENTAL_UNCHANGED

};

// The nested namespace is to contain all the global variables and

// structs that need to be defined in the .h file, but do not need to

// be used outside this class.

namespace options

{

typedef std::vector<Search_directory> Dir_list;

typedef Unordered_set<std::string> String_set;

// These routines convert from a string option to various types.

// Each gives a fatal error if it cannot parse the argument.

extern void

parse_bool(const char* option_name, const char* arg, bool* retval);

extern void

parse_int(const char* option_name, const char* arg, int* retval);

extern void

parse_uint(const char* option_name, const char* arg, int* retval);

extern void

parse_uint64(const char* option_name, const char* arg, uint64_t* retval);

extern void

parse_double(const char* option_name, const char* arg, double* retval);

extern void

parse_string(const char* option_name, const char* arg, const char** retval);

extern void

parse_optional_string(const char* option_name, const char* arg,

                      const char** retval);

extern void

parse_dirlist(const char* option_name, const char* arg, Dir_list* retval);

extern void

parse_set(const char* option_name, const char* arg, String_set* retval);

extern void

parse_choices(const char* option_name, const char* arg, const char** retval,

              const char* choices[], int num_choices);

struct Struct_var;

// Most options have both a shortname (one letter) and a longname.

// This enum controls how many dashes are expected for longname access

// -- shortnames always use one dash.  Most longnames will accept

// either one dash or two; the only difference between ONE_DASH and

// TWO_DASHES is how we print the option in --help.  However, some

// longnames require two dashes, and some require only one.  The

// special value DASH_Z means that the option is preceded by "-z".

enum Dashes

{

  ONE_DASH, TWO_DASHES, EXACTLY_ONE_DASH, EXACTLY_TWO_DASHES, DASH_Z

};

// LONGNAME is the long-name of the option with dashes converted to

//    underscores, or else the short-name if the option has no long-name.

//    It is never the empty string.

// DASHES is an instance of the Dashes enum: ONE_DASH, TWO_DASHES, etc.

// SHORTNAME is the short-name of the option, as a char, or '\0' if the

//    option has no short-name.  If the option has no long-name, you

//    should specify the short-name in *both* VARNAME and here.

// DEFAULT_VALUE is the value of the option if not specified on the

//    commandline, as a string.

// HELPSTRING is the descriptive text used with the option via --help

// HELPARG is how you define the argument to the option.

//    --help output is "-shortname HELPARG, --longname HELPARG: HELPSTRING"

//    HELPARG should be NULL iff the option is a bool and takes no arg.

// OPTIONAL_ARG is true if this option takes an optional argument.  An

//    optional argument must be specifid as --OPTION=VALUE, not

//    --OPTION VALUE.

// READER provides parse_to_value, which is a function that will convert

//    a char* argument into the proper type and store it in some variable.

// A One_option struct initializes itself with the global list of options

// at constructor time, so be careful making one of these.

struct One_option

{

  std::string longname;

  Dashes dashes;

  char shortname;

  const char* default_value;

  const char* helpstring;

  const char* helparg;

  bool optional_arg;

  Struct_var* reader;

  One_option(const char* ln, Dashes d, char sn, const char* dv,

             const char* hs, const char* ha, bool oa, Struct_var* r)

    : longname(ln), dashes(d), shortname(sn), default_value(dv ? dv : ""),

      helpstring(hs), helparg(ha), optional_arg(oa), reader(r)

  {

    // In longname, we convert all underscores to dashes, since GNU

    // style uses dashes in option names.  longname is likely to have

    // underscores in it because it's also used to declare a C++

    // function.

    const char* pos = strchr(this->longname.c_str(), '_');

    for (; pos; pos = strchr(pos, '_'))

      this->longname[pos - this->longname.c_str()] = '-';

    // We only register ourselves if our helpstring is not NULL.  This

    // is to support the "no-VAR" boolean variables, which we

    // conditionally turn on by defining "no-VAR" help text.

    if (this->helpstring)

      this->register_option();

  }

  // This option takes an argument iff helparg is not NULL.

  bool

  takes_argument() const

  { return this->helparg != NULL; }

  // Whether the argument is optional.

  bool

  takes_optional_argument() const

  { return this->optional_arg; }

  // Register this option with the global list of options.

  void

  register_option();

  // Print this option to stdout (used with --help).

  void

  print() const;

};

// All options have a Struct_##varname that inherits from this and

// actually implements parse_to_value for that option.

struct Struct_var

{

  // OPTION: the name of the option as specified on the commandline,

  //    including leading dashes, and any text following the option:

  //    "-O", "--defsym=mysym=0x1000", etc.

  // ARG: the arg associated with this option, or NULL if the option

  //    takes no argument: "2", "mysym=0x1000", etc.

  // CMDLINE: the global Command_line object.  Used by DEFINE_special.

  // OPTIONS: the global General_options object.  Used by DEFINE_special.

  virtual void

  parse_to_value(const char* option, const char* arg,

                 Command_line* cmdline, General_options* options) = 0;

  virtual

  ~Struct_var()  // To make gcc happy.

  { }

};

// This is for "special" options that aren't of any predefined type.

struct Struct_special : public Struct_var

{

  // If you change this, change the parse-fn in DEFINE_special as well.

  typedef void (General_options::*Parse_function)(const char*, const char*,

                                                  Command_line*);

  Struct_special(const char* varname, Dashes dashes, char shortname,

                 Parse_function parse_function,

                 const char* helpstring, const char* helparg)

    : option(varname, dashes, shortname, "", helpstring, helparg, false, this),

      parse(parse_function)

  { }

  void parse_to_value(const char* option, const char* arg,

                      Command_line* cmdline, General_options* options)

  { (options->*(this->parse))(option, arg, cmdline); }

  One_option option;

  Parse_function parse;

};

}  // End namespace options.

// These are helper macros use by DEFINE_uint64/etc below.

// This macro is used inside the General_options_ class, so defines

// var() and set_var() as General_options methods.  Arguments as are

// for the constructor for One_option.  param_type__ is the same as

// type__ for built-in types, and "const type__ &" otherwise.

//

// When we define the linker command option "assert", the macro argument

// varname__ of DEFINE_var below will be replaced by "assert".  On Mac OSX

// assert.h is included implicitly by one of the library headers we use.  To

// avoid unintended macro substitution of "assert()", we need to enclose

// varname__ with parenthese.

#define DEFINE_var(varname__, dashes__, shortname__, default_value__,        \

                   default_value_as_string__, helpstring__, helparg__,       \

                   optional_arg__, type__, param_type__, parse_fn__)         \

 public:                                                                     \

  param_type__                                                               \

  (varname__)() const                                                        \

  { return this->varname__##_.value; }                                       \

                                                                             \

  bool                                                                       \

  user_set_##varname__() const                                               \

  { return this->varname__##_.user_set_via_option; }                         \

                                                                             \

  void                                                                       \

  set_user_set_##varname__()                                                 \

  { this->varname__##_.user_set_via_option = true; }                         \

                                                                             \

 private:                                                                    \

  struct Struct_##varname__ : public options::Struct_var                     \

  {                                                                          \

    Struct_##varname__()                                                     \

      : option(#varname__, dashes__, shortname__, default_value_as_string__, \

               helpstring__, helparg__, optional_arg__, this),               \

        user_set_via_option(false), value(default_value__)                   \

    { }                                                                      \

                                                                             \

    void                                                                     \

    parse_to_value(const char* option_name, const char* arg,                 \

                   Command_line*, General_options*)                          \

    {                                                                        \

      parse_fn__(option_name, arg, &this->value);                            \

      this->user_set_via_option = true;                                      \

    }                                                                        \

                                                                             \

    options::One_option option;                                              \

    bool user_set_via_option;                                                \

    type__ value;                                                            \

  };                                                                         \

  Struct_##varname__ varname__##_;                                           \

  void                                                                       \

  set_##varname__(param_type__ value)                                        \

  { this->varname__##_.value = value; }

// These macros allow for easy addition of a new commandline option.

// If no_helpstring__ is not NULL, then in addition to creating

// VARNAME, we also create an option called no-VARNAME (or, for a -z

// option, noVARNAME).

#define DEFINE_bool(varname__, dashes__, shortname__, default_value__,   \

                    helpstring__, no_helpstring__)                       \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,          \

             default_value__ ? "true" : "false", helpstring__, NULL,     \

             false, bool, bool, options::parse_bool)                     \

  struct Struct_no_##varname__ : public options::Struct_var              \

  {                                                                      \

    Struct_no_##varname__() : option((dashes__ == options::DASH_Z        \

                                      ? "no" #varname__                  \

                                      : "no-" #varname__),               \

                                     dashes__, '\0',                     \

                                     default_value__ ? "false" : "true", \

                                     no_helpstring__, NULL, false, this) \

    { }                                                                  \

                                                                         \

    void                                                                 \

    parse_to_value(const char*, const char*,                             \

                   Command_line*, General_options* options)              \

    {                                                                    \

      options->set_##varname__(false);                                   \

      options->set_user_set_##varname__();                               \

    }                                                                    \

                                                                         \

    options::One_option option;                                          \

  };                                                                     \

  Struct_no_##varname__ no_##varname__##_initializer_

#define DEFINE_enable(varname__, dashes__, shortname__, default_value__, \

                      helpstring__, no_helpstring__)                     \

  DEFINE_var(enable_##varname__, dashes__, shortname__, default_value__, \

             default_value__ ? "true" : "false", helpstring__, NULL,     \

             false, bool, bool, options::parse_bool)                     \

  struct Struct_disable_##varname__ : public options::Struct_var         \

  {                                                                      \

    Struct_disable_##varname__() : option("disable-" #varname__,         \

                                     dashes__, '\0',                     \

                                     default_value__ ? "false" : "true", \

                                     no_helpstring__, NULL, false, this) \

    { }                                                                  \

                                                                         \

    void                                                                 \

    parse_to_value(const char*, const char*,                             \

                   Command_line*, General_options* options)              \

    { options->set_enable_##varname__(false); }                          \

                                                                         \

    options::One_option option;                                          \

  };                                                                     \

  Struct_disable_##varname__ disable_##varname__##_initializer_

#define DEFINE_int(varname__, dashes__, shortname__, default_value__,   \

                   helpstring__, helparg__)                             \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,         \

             #default_value__, helpstring__, helparg__, false,          \

             int, int, options::parse_int)

#define DEFINE_uint(varname__, dashes__, shortname__, default_value__,  \

                   helpstring__, helparg__)                             \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,         \

             #default_value__, helpstring__, helparg__, false,          \

             int, int, options::parse_uint)

#define DEFINE_uint64(varname__, dashes__, shortname__, default_value__, \

                      helpstring__, helparg__)                           \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,          \

             #default_value__, helpstring__, helparg__, false,           \

             uint64_t, uint64_t, options::parse_uint64)

#define DEFINE_double(varname__, dashes__, shortname__, default_value__, \

                      helpstring__, helparg__)                           \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,          \

             #default_value__, helpstring__, helparg__, false,           \

             double, double, options::parse_double)

#define DEFINE_string(varname__, dashes__, shortname__, default_value__, \

                      helpstring__, helparg__)                           \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,          \

             default_value__, helpstring__, helparg__, false,            \

             const char*, const char*, options::parse_string)

// This is like DEFINE_string, but we convert each occurrence to a

// Search_directory and store it in a vector.  Thus we also have the

// add_to_VARNAME() method, to append to the vector.

#define DEFINE_dirlist(varname__, dashes__, shortname__,                  \

                           helpstring__, helparg__)                       \

  DEFINE_var(varname__, dashes__, shortname__, ,                          \

             "", helpstring__, helparg__, false, options::Dir_list,       \

             const options::Dir_list&, options::parse_dirlist)            \

  void                                                                    \

  add_to_##varname__(const char* new_value)                               \

  { options::parse_dirlist(NULL, new_value, &this->varname__##_.value); } \

  void                                                                    \

  add_search_directory_to_##varname__(const Search_directory& dir)        \

  { this->varname__##_.value.push_back(dir); }

// This is like DEFINE_string, but we store a set of strings.

#define DEFINE_set(varname__, dashes__, shortname__,                      \

                   helpstring__, helparg__)                               \

  DEFINE_var(varname__, dashes__, shortname__, ,                          \

             "", helpstring__, helparg__, false, options::String_set,     \

             const options::String_set&, options::parse_set)              \

 public:                                                                  \

  bool                                                                    \

  any_##varname__() const                                                 \

  { return !this->varname__##_.value.empty(); }                           \

                                                                          \

  bool                                                                    \

  is_##varname__(const char* symbol) const                                \

  {                                                                       \

    return (!this->varname__##_.value.empty()                             \

            && (this->varname__##_.value.find(std::string(symbol))        \

                != this->varname__##_.value.end()));                      \

  }                                                                       \

                                                                          \

  options::String_set::const_iterator                                     \

  varname__##_begin() const                                               \

  { return this->varname__##_.value.begin(); }                            \

                                                                          \

  options::String_set::const_iterator                                     \

  varname__##_end() const                                                 \

  { return this->varname__##_.value.end(); }

// When you have a list of possible values (expressed as string)

// After helparg__ should come an initializer list, like

//   {"foo", "bar", "baz"}

#define DEFINE_enum(varname__, dashes__, shortname__, default_value__,   \

                    helpstring__, helparg__, ...)                        \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,          \

             default_value__, helpstring__, helparg__, false,            \

             const char*, const char*, parse_choices_##varname__)        \

 private:                                                                \

  static void parse_choices_##varname__(const char* option_name,         \

                                        const char* arg,                 \

                                        const char** retval) {           \

    const char* choices[] = __VA_ARGS__;                                 \

    options::parse_choices(option_name, arg, retval,                     \

                           choices, sizeof(choices) / sizeof(*choices)); \

  }

// This is like DEFINE_bool, but VARNAME is the name of a different

// option.  This option becomes an alias for that one.  INVERT is true

// if this option is an inversion of the other one.

#define DEFINE_bool_alias(option__, varname__, dashes__, shortname__,   \

                          helpstring__, no_helpstring__, invert__)      \

 private:                                                               \

  struct Struct_##option__ : public options::Struct_var                 \

  {                                                                     \

    Struct_##option__()                                                 \

      : option(#option__, dashes__, shortname__, "", helpstring__,      \

               NULL, false, this)                                       \

    { }                                                                 \

                                                                        \

    void                                                                \

    parse_to_value(const char*, const char*,                            \

                   Command_line*, General_options* options)             \

    {                                                                   \

      options->set_##varname__(!invert__);                              \

      options->set_user_set_##varname__();                              \

    }                                                                   \

                                                                        \

    options::One_option option;                                         \

  };                                                                    \

  Struct_##option__ option__##_;                                        \

                                                                        \

  struct Struct_no_##option__ : public options::Struct_var              \

  {                                                                     \

    Struct_no_##option__()                                              \

      : option((dashes__ == options::DASH_Z                             \

                ? "no" #option__                                        \

                : "no-" #option__),                                     \

               dashes__, '\0', "", no_helpstring__,                     \

               NULL, false, this)                                       \

    { }                                                                 \

                                                                        \

    void                                                                \

    parse_to_value(const char*, const char*,                            \

                   Command_line*, General_options* options)             \

    {                                                                   \

      options->set_##varname__(invert__);                               \

      options->set_user_set_##varname__();                              \

    }                                                                   \

                                                                        \

    options::One_option option;                                         \

  };                                                                    \

  Struct_no_##option__ no_##option__##_initializer_

// This is used for non-standard flags.  It defines no functions; it

// just calls General_options::parse_VARNAME whenever the flag is

// seen.  We declare parse_VARNAME as a static member of

// General_options; you are responsible for defining it there.

// helparg__ should be NULL iff this special-option is a boolean.

#define DEFINE_special(varname__, dashes__, shortname__,                \

                       helpstring__, helparg__)                         \

 private:                                                               \

  void parse_##varname__(const char* option, const char* arg,           \

                         Command_line* inputs);                         \

  struct Struct_##varname__ : public options::Struct_special            \

  {                                                                     \

    Struct_##varname__()                                                \

      : options::Struct_special(#varname__, dashes__, shortname__,      \

                                &General_options::parse_##varname__,    \

                                helpstring__, helparg__)                \

    { }                                                                 \

  };                                                                    \

  Struct_##varname__ varname__##_initializer_

// An option that takes an optional string argument.  If the option is

// used with no argument, the value will be the default, and

// user_set_via_option will be true.

#define DEFINE_optional_string(varname__, dashes__, shortname__,        \

                               default_value__,                         \

                               helpstring__, helparg__)                 \

  DEFINE_var(varname__, dashes__, shortname__, default_value__,         \

             default_value__, helpstring__, helparg__, true,            \

             const char*, const char*, options::parse_optional_string)

// A directory to search.  For each directory we record whether it is

// in the sysroot.  We need to know this so that, if a linker script

// is found within the sysroot, we will apply the sysroot to any files

// named by that script.

class Search_directory

{

 public:

  // We need a default constructor because we put this in a

  // std::vector.

  Search_directory()

    : name_(NULL), put_in_sysroot_(false), is_in_sysroot_(false)

  { }

  // This is the usual constructor.

  Search_directory(const char* name, bool put_in_sysroot)

    : name_(name), put_in_sysroot_(put_in_sysroot), is_in_sysroot_(false)

  {

    if (this->name_.empty())

      this->name_ = ".";

  }

  // This is called if we have a sysroot.  The sysroot is prefixed to

  // any entries for which put_in_sysroot_ is true.  is_in_sysroot_ is

  // set to true for any enries which are in the sysroot (this will

  // naturally include any entries for which put_in_sysroot_ is true).

  // SYSROOT is the sysroot, CANONICAL_SYSROOT is the result of

  // passing SYSROOT to lrealpath.

  void

  add_sysroot(const char* sysroot, const char* canonical_sysroot);

  // Get the directory name.

  const std::string&

  name() const

  { return this->name_; }

  // Return whether this directory is in the sysroot.

  bool

  is_in_sysroot() const

  { return this->is_in_sysroot_; }

  // Return whether this is considered a system directory.

  bool

  is_system_directory() const

  { return this->put_in_sysroot_ || this->is_in_sysroot_; }

 private:

  // The directory name.

  std::string name_;

  // True if the sysroot should be added as a prefix for this

  // directory (if there is a sysroot).  This is true for system

  // directories that we search by default.

  bool put_in_sysroot_;

  // True if this directory is in the sysroot (if there is a sysroot).

  // This is true if there is a sysroot and either 1) put_in_sysroot_

  // is true, or 2) the directory happens to be in the sysroot based

  // on a pathname comparison.

  bool is_in_sysroot_;

};

class General_options

{

 private:

  // NOTE: For every option that you add here, also consider if you

  // should add it to Position_dependent_options.

  DEFINE_special(help, options::TWO_DASHES, '\0',

                 N_("Report usage information"), NULL);

  DEFINE_special(version, options::TWO_DASHES, 'v',

                 N_("Report version information"), NULL);

  DEFINE_special(V, options::EXACTLY_ONE_DASH, '\0',

                 N_("Report version and target information"), NULL);

  // These options are sorted approximately so that for each letter in

  // the alphabet, we show the option whose shortname is that letter

  // (if any) and then every longname that starts with that letter (in

  // alphabetical order).  For both, lowercase sorts before uppercase.

  // The -z options come last.

  DEFINE_bool(add_needed, options::TWO_DASHES, '\0', false,

              N_("Not supported"),

              N_("Do not copy DT_NEEDED tags from shared libraries"));

  DEFINE_bool_alias(allow_multiple_definition, muldefs, options::TWO_DASHES,

                    '\0', N_("Allow multiple definitions of symbols"),

                    N_("Do not allow multiple definitions"), false);

  DEFINE_bool(allow_shlib_undefined, options::TWO_DASHES, '\0', false,

              N_("Allow unresolved references in shared libraries"),

              N_("Do not allow unresolved references in shared libraries"));

  DEFINE_bool(as_needed, options::TWO_DASHES, '\0', false,

              N_("Only set DT_NEEDED for shared libraries if used"),

              N_("Always DT_NEEDED for shared libraries"));

  DEFINE_enum(assert, options::ONE_DASH, '\0', NULL,

              N_("Ignored"), N_("[ignored]"),

              {"definitions", "nodefinitions", "nosymbolic", "pure-text"});

  // This should really be an "enum", but it's too easy for folks to

  // forget to update the list as they add new targets.  So we just

  // accept any string.  We'll fail later (when the string is parsed),

  // if the target isn't actually supported.

  DEFINE_string(format, options::TWO_DASHES, 'b', "elf",

                N_("Set input format"), ("[elf,binary]"));

  DEFINE_bool(Bdynamic, options::ONE_DASH, '\0', true,

              N_("-l searches for shared libraries"), NULL);

  DEFINE_bool_alias(Bstatic, Bdynamic, options::ONE_DASH, '\0',

                    N_("-l does not search for shared libraries"), NULL,

                    true);

  DEFINE_bool_alias(dy, Bdynamic, options::ONE_DASH, '\0',

                    N_("alias for -Bdynamic"), NULL, false);

  DEFINE_bool_alias(dn, Bdynamic, options::ONE_DASH, '\0',

                    N_("alias for -Bstatic"), NULL, true);

  DEFINE_bool(Bsymbolic, options::ONE_DASH, '\0', false,

              N_("Bind defined symbols locally"), NULL);

  DEFINE_bool(Bsymbolic_functions, options::ONE_DASH, '\0', false,

              N_("Bind defined function symbols locally"), NULL);

  DEFINE_optional_string(build_id, options::TWO_DASHES, '\0', "sha1",

                         N_("Generate build ID note"),

                         N_("[=STYLE]"));

  DEFINE_bool(check_sections, options::TWO_DASHES, '\0', true,

              N_("Check segment addresses for overlaps (default)"),

              N_("Do not check segment addresses for overlaps"));

#ifdef HAVE_ZLIB_H

  DEFINE_enum(compress_debug_sections, options::TWO_DASHES, '\0', "none",

              N_("Compress .debug_* sections in the output file"),

              ("[none,zlib]"),

              {"none", "zlib"});

#else

  DEFINE_enum(compress_debug_sections, options::TWO_DASHES, '\0', "none",

              N_("Compress .debug_* sections in the output file"),

              N_("[none]"),

              {"none"});

#endif

  DEFINE_bool(copy_dt_needed_entries, options::TWO_DASHES, '\0', false,

              N_("Not supported"),

              N_("Do not copy DT_NEEDED tags from shared libraries"));

  DEFINE_bool(cref, options::TWO_DASHES, '\0', false,

              N_("Output cross reference table"),

              N_("Do not output cross reference table"));

  DEFINE_bool(define_common, options::TWO_DASHES, 'd', false,

              N_("Define common symbols"),

              N_("Do not define common symbols"));

  DEFINE_bool(dc, options::ONE_DASH, '\0', false,

              N_("Alias for -d"), NULL);

  DEFINE_bool(dp, options::ONE_DASH, '\0', false,

              N_("Alias for -d"), NULL);

  DEFINE_string(debug, options::TWO_DASHES, '\0', "",

                N_("Turn on debugging"),

                N_("[all,files,script,task][,...]"));

  DEFINE_special(defsym, options::TWO_DASHES, '\0',

                 N_("Define a symbol"), N_("SYMBOL=EXPRESSION"));