def __init__(
        self,
        _platform=None,
        _tools=None,
        toolpath=None,
        variables=None,
        parse_flags=None,
        **kw
    ):
        """Create a new MacEnvironment instance."""

        PosixEnvironment.__init__(
            self,
            _platform,
            _tools,
            toolpath,
            variables,
            parse_flags,
            **kw
        )

        if any("-m64" in s for s in self['CXXFLAGS']):
            self['CXXFLAGS'].remove('-m64')
            self['LINKFLAGS'].remove('-m64')
        if any("-m32" in s for s in self['CXXFLAGS']):
            self['CXXFLAGS'].remove('-m32')
            self['LINKFLAGS'].remove('-m32')

        self['CXXFLAGS'].append('-arch')
        self['CXXFLAGS'].append('x86_64')

        # if compiled from sources, additionnal libs are in /usr/local/lib       
        self['LINKFLAGS'].append('-L/usr/local/lib')
        self['LINKFLAGS'].append('-arch')
        self['LINKFLAGS'].append('x86_64')

        self['BOOST_PREFIX'] = {}
        self['BOOST_PREFIX']['release'] = os.environ.get('FREELAN_RELEASE_BOOST_PREFIX')
        self['BOOST_PREFIX']['debug'] = os.environ.get('FREELAN_DEBUG_BOOST_PREFIX', self['BOOST_PREFIX']['release'])
        self['BOOST_SUFFIX'] = {}
        self['BOOST_SUFFIX']['release'] = os.environ.get('FREELAN_RELEASE_BOOST_SUFFIX')
        self['BOOST_SUFFIX']['debug'] = os.environ.get('FREELAN_DEBUG_BOOST_SUFFIX', self['BOOST_SUFFIX']['release'])
    def __init__(
        self,
        _platform=None,
        _tools=None,
        toolpath=None,
        variables=None,
        parse_flags=None,
        **kw
    ):
        """Create a new MacEnvironment instance."""

        PosixEnvironment.__init__(
            self,
            _platform,
            _tools,
            toolpath,
            variables,
            parse_flags,
            **kw
        )

        if any("-m64" in s for s in self['CXXFLAGS']):
            self['CXXFLAGS'].remove('-m64')
            self['LINKFLAGS'].remove('-m64')
        if any("-m32" in s for s in self['CXXFLAGS']):
            self['CXXFLAGS'].remove('-m32')
            self['LINKFLAGS'].remove('-m32')

        self['CXXFLAGS'].append('-arch')
        self['CXXFLAGS'].append('i386')
        self['CXXFLAGS'].append('-arch')
        self['CXXFLAGS'].append('x86_64')

        # if compiled from sources, additionnal libs are in /usr/local/lib       
        self['LINKFLAGS'].append('-L/usr/local/lib')
        self['LINKFLAGS'].append('-arch')
        self['LINKFLAGS'].append('i386')
        self['LINKFLAGS'].append('-arch')
        self['LINKFLAGS'].append('x86_64')