diff --git a/Objects/abstract.c b/Objects/abstract.c
index 3315b0eb632..0ec6dee2cda 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2911,7 +2911,7 @@ PyObject_IsInstance(PyObject *inst, PyObject *cls)
 	PyObject *checker;
 
 	/* Quick test for an exact match */
-	if (Py_TYPE(inst) == cls)
+	if (Py_TYPE(inst) == (PyTypeObject *)cls)
 		return 1;
 
 	PyErr_Fetch(&t, &v, &tb);