diff --git a/ext/gmp/tests/gmp_dynamic_property.phpt b/ext/gmp/tests/gmp_dynamic_property.phpt
index 547fe51a7f6a3..ff3d4ac94e012 100644
--- a/ext/gmp/tests/gmp_dynamic_property.phpt
+++ b/ext/gmp/tests/gmp_dynamic_property.phpt
@@ -5,7 +5,7 @@ gmp
 --FILE--
 <?php
 
-$g = new GMP();
+$g = gmp_init(0);
 $g->{1} = 123;
 
 $serialized = serialize($g);