mt_state*  O_OBJECT
uint32_t   T_UV
uint64_t   T_UV

OUTPUT
O_OBJECT
  sv_setref_pv($arg, CLASS, (void*)$var);

INPUT
O_OBJECT
  if ( !sv_isobject($arg) || (SvTYPE(SvRV($arg)) != SVt_PVMG) ) {
    warn(\"${Package}::$func_name() -- $var is not a blessed SV reference\");
    XSRETURN_UNDEF;
  }
  $var = ($type)SvIV((SV*)SvRV($arg));
  *$var = *$var; /* tell the compiler that $var is not NULL */
