def _unix_args_to_native(cls, args: T.List[str], info: MachineInfo) -> T.List[str]:
        "Always returns a copy that can be independently mutated"
        patched_args: T.List[str] = []
        for arg in args:
            added = 0
            for ptrn in ccomp_args_to_wul:
                if re.match(ptrn, arg):
                    patched_args.append('-WUl,' + arg)
                    added = 1
            if not added:
                patched_args.append(arg)
        return patched_args
Always returns a copy that can be independently mutated
mesonbuild/compilers/mixins/compcert.py