def _cc_feature_configuration(feature_configuration):
    """Returns the C++ feature configuration nested inside the given Swift feature configuration.

    Args:
        feature_configuration: The Swift feature configuration, as returned from
            `swift_common.configure_features`.

    Returns:
        A C++ `FeatureConfiguration` value (see `cc_common` for more information).
    """
    return feature_configuration.cc_feature_configuration