#if defined ENABLE_RTL_CHECKING && (GCC_VERSION >= 2007)
#define REG_CHECK(RTX) __extension__ \
({ __typeof (RTX) const _rtx = (RTX); \
if (GET_CODE (_rtx) != REG) \
rtl_check_failed_code1 (_rtx, REG, __FILE__, __LINE__, \
__FUNCTION__); \
&_rtx->u.reg; })
#else /* not ENABLE_RTL_CHECKING */
#define REG_CHECK(RTX) (&(RTX)->u.reg)
#endif