def __check_libfiles(self, shared: bool) -> None:
        """Use llvm-config's --libfiles to check if libraries exist."""
        mode = '--link-shared' if shared else '--link-static'

        # Set self.required to true to force an exception in get_config_value
        # if the returncode != 0
        restore = self.required
        self.required = True

        try:
            # It doesn't matter what the stage is, the caller needs to catch
            # the exception anyway.
            self.link_args = self.get_config_value(['--libfiles', mode], '')
        finally:
            self.required = restore
Use llvm-config's --libfiles to check if libraries exist.
mesonbuild/dependencies/dev.py