check_WRITE_METADATA(const struct ofpact_metadata *a OVS_UNUSED,
                     const struct ofpact_check_params *cp OVS_UNUSED)
{
    return 0;
}
check_WRITE_METADATA(const struct ofpact_metadata *a OVS_UNUSED,
                     const struct ofpact_check_params *cp OVS_UNUSED)
{
    return 0;
}