Use type-checked ref assignment in UConverter

Author: nikic

ext/intl/converter/converter.c

@@ -63,9 +63,6 @@ static inline void php_converter_throw_failure(php_converter_object *objval, UEr
 
 /* {{{ php_converter_default_callback */
 static void php_converter_default_callback(zval *return_value, zval *zobj, zend_long reason, zval *error) {
-	ZVAL_DEREF(error);
-	zval_ptr_dtor(error);
-	ZVAL_LONG(error, U_ZERO_ERROR);
 	/* Basic functionality so children can call parent::toUCallback() */
 	switch (reason) {
 		case UCNV_UNASSIGNED:
@@ -81,7 +78,7 @@ static void php_converter_default_callback(zval *return_value, zval *zobj, zend_
 				chars[0] = 0x1A;
 				chars[1] = 0;
 				chars_len = 1;
-                ZVAL_LONG(error, U_INVALID_STATE_ERROR);
+				ZEND_TRY_ASSIGN_REF_LONG(error, U_INVALID_STATE_ERROR);
                 RETVAL_STRINGL(chars, chars_len);
                 return;
             }
@@ -99,8 +96,8 @@ static void php_converter_default_callback(zval *return_value, zval *zobj, zend_
 				chars[0] = 0x1A;
 				chars[1] = 0;
 				chars_len = 1;
-            	ZVAL_LONG(error, uerror);
 			}
+			ZEND_TRY_ASSIGN_REF_LONG(error, uerror);
 			RETVAL_STRINGL(chars, chars_len);
 		}
 	}