Function compiler_fixup

Lib/_osx_support.py:359–436

This function will strip '-isysroot PATH' and '-arch ARCH' from the compile flags if the user has specified one them in extra_compile_flags. This is needed because '-arch ARCH' adds another architecture to the build, without a way to remove an architecture. Furthermore GCC will

(compiler_so, cc_args)

def compiler_fixup(compiler_so, cc_args):
    """
    This function will strip '-isysroot PATH' and '-arch ARCH' from the
    compile flags if the user has specified one them in extra_compile_flags.

    This is needed because '-arch ARCH' adds another architecture to the
    build, without a way to remove an architecture. Furthermore GCC will
    barf if multiple '-isysroot' arguments are present.
    """
    stripArch = stripSysroot = False

    compiler_so = list(compiler_so)

    if not _supports_universal_builds():
        # OSX before 10.4.0, these don't support -arch and -isysroot at
        # all.
        stripArch = stripSysroot = True
    else:
        stripArch = '-arch' in cc_args
        stripSysroot = any(arg for arg in cc_args if arg.startswith('-isysroot'))

    if stripArch or 'ARCHFLAGS' in os.environ:
        while True:
            try:
                index = compiler_so.index('-arch')
                # Strip this argument and the next one:
                del compiler_so[index:index+2]
            except ValueError:
                break

    elif not _supports_arm64_builds():
        # Look for "-arch arm64" and drop that
        for idx in reversed(range(len(compiler_so))):
            if compiler_so[idx] == '-arch' and compiler_so[idx+1] == "arm64":
                del compiler_so[idx:idx+2]

    if 'ARCHFLAGS' in os.environ and not stripArch:
        # User specified different -arch flags in the environ,
        # see also distutils.sysconfig
        compiler_so = compiler_so + os.environ['ARCHFLAGS'].split()

    if stripSysroot:
        while True:
            indices = [i for i,x in enumerate(compiler_so) if x.startswith('-isysroot')]
            if not indices:
                break
            index = indices[0]
            if compiler_so[index] == '-isysroot':
                # Strip this argument and the next one:
                del compiler_so[index:index+2]
            else:
                # It's '-isysroot/some/path' in one arg
                del compiler_so[index:index+1]

    # Check if the SDK that is used during compilation actually exists,
    # the universal build requires the usage of a universal SDK and not all
    # users have that installed by default.
    sysroot = None