diff --git a/ext/phar/phar_object.c b/ext/phar/phar_object.c
index 17000ca3c0f17..9bae92f004b6e 100644
--- a/ext/phar/phar_object.c
+++ b/ext/phar/phar_object.c
@@ -1828,7 +1828,7 @@ PHP_METHOD(Phar, buildFromIterator)
 	zend_string *base = ZSTR_EMPTY_ALLOC();
 	struct _phar_t pass;
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS(), "O|S!", &obj, zend_ce_traversable, &base) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS(), "O|P!", &obj, zend_ce_traversable, &base) == FAILURE) {
 		RETURN_THROWS();
 	}