ZEND_SEND_BY_REF  850 Zend/zend_compile.h 	CHECK_ARG_SEND_TYPE(zf, arg_num, ZEND_SEND_BY_REF)
ZEND_SEND_BY_REF  853 Zend/zend_compile.h 	CHECK_ARG_SEND_TYPE(zf, arg_num, ZEND_SEND_BY_REF|ZEND_SEND_PREFER_REF)
ZEND_SEND_BY_REF 2522 ext/reflection/php_reflection.c 	RETVAL_BOOL(param->arg_info->pass_by_reference != ZEND_SEND_BY_REF);