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ExtUtils::CppGuess(3) User Contributed Perl Documentation ExtUtils::CppGuess(3)

NAME

ExtUtils::CppGuess - guess C++ compiler and flags

SYNOPSIS

With Extutils::MakeMaker:

    use ExtUtils::CppGuess;
    my $guess = ExtUtils::CppGuess->new;
    WriteMakefile
      ( # MakeMaker args,
        $guess->makemaker_options,
        );

With Module::Build:

    my $guess = ExtUtils::CppGuess->new;
    my $build = Module::Build->new
      ( # Module::Build arguments
        $guess->module_build_options,
        );
    $build->create_build_script;

DESCRIPTION

"ExtUtils::CppGuess" attempts to guess the system's C++ compiler that is compatible with the C compiler that your perl was built with.

It can generate the necessary options to the Module::Build constructor or to ExtUtils::MakeMaker's "WriteMakefile" function.

ENVIRONMENT

As of 0.24, the environment variable "CXX" defines the obvious value, and will be used instead of any detection. Supplied arguments to "new" will still win.

METHODS

new

Creates a new "ExtUtils::CppGuess" object. Takes the path to the C compiler as the "cc" argument, but falls back to the value of $Config{cc}, which should be what you want anyway.

You can specify "extra_compiler_flags" and "extra_linker_flags" (as strings) which will be merged in with the auto-detected ones.

module_build_options

Returns the correct options to the constructor of "Module::Build". These are:

    extra_compiler_flags
    extra_linker_flags
    config => { cc => ... }, # as of 0.15

Please note the above may have problems on Perl <= 5.8 with ExtUtils::CBuilder <= 0.280230 due to a Perl RE issue.

makemaker_options

Returns the correct options to the "WriteMakefile" function of "ExtUtils::MakeMaker". These are:

    CCFLAGS
    dynamic_lib => { OTHERLDFLAGS => ... }
    CC # as of 0.15

If you specify the extra compiler or linker flags in the constructor, they'll be merged into "CCFLAGS" or "OTHERLDFLAGS" respectively.

is_gcc

Returns true if the detected compiler is in the gcc family.

is_msvc

Returns true if the detected compiler is in the MS VC family.

is_clang

Returns true if the detected compiler is in the Clang family.

is_sunstudio

Returns true if the detected compiler is in the Sun Studio family.

add_extra_compiler_flags

Takes a string as argument that is added to the string of extra compiler flags.

add_extra_linker_flags

Takes a string as argument that is added to the string of extra linker flags.

compiler_command

Returns the string that can be passed to "system" to execute the compiler. Will include the flags returned as the Module::Build "extra_compiler_flags".

Added in 0.13.

linker_flags

The same as returned as the Module::Build "extra_linker_flags".

Added in 0.13.

iostream_fname

Returns the filename to "#include" to get iostream capability.

This can be used a bit creatively to be portable in one's XS files, as the tests for this module need to be:

  # in Makefile.PL:
  $guess->add_extra_compiler_flags(
    '-DINCLUDE_DOT=' .
    ($guess->iostream_fname =~ /\./ ? 1 : 0)
  );
  // in your .xs file:
  #if INCLUDE_DOT
  #include <string.h>
  #else
  #include <string>
  #endif

Added in 0.15.

cpp_flavor_defs

Returns the text for a header that "#define"s "__INLINE_CPP_STANDARD_HEADERS" and "__INLINE_CPP_NAMESPACE_STD" if the standard headers and namespace are available. This is determined by trying to compile C++ with "#define <iostream>" - if it succeeds, the symbols will be defined, else commented.

Added in 0.15.

cpp_standard_flag

  $guess->cpp_standard_flag( $standard_name )

Given a string $standard_name that is currently one of

  • "C++98"
  • "C++11"
  • "C++14"
  • "C++17"
  • "C++20"
  • "C++23"

returns a string with a flag that can be used to tell the compiler to support that version of the C++ standard or dies if version is not supported.

Added in version v0.22.

AUTHOR

Mattia Barbon <mbarbon@cpan.org>

Steffen Mueller <smueller@cpan.org>

Tobias Leich <froggs@cpan.org>

COPYRIGHT AND LICENSE

Copyright 2010, 2011 by Mattia Barbon.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

2024-03-08 perl v5.40.0