onig_name_to_backref_number(regex_t* reg, const UChar* name,
                            const UChar* name_end, OnigRegion* region)
{
  return ONIG_NO_SUPPORT_CONFIG;
}
onig_name_to_backref_number(regex_t* reg, const UChar* name,
                            const UChar* name_end, OnigRegion* region)
{
  return ONIG_NO_SUPPORT_CONFIG;
}