diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py
index 4b6b7cf..fa43078 100755
--- a/Parser/asdl_c.py
+++ b/Parser/asdl_c.py
@@ -958,7 +958,7 @@
 {
     mod_ty res;
     init_types();
-    if (!PyObject_IsInstance(ast, mod_type)) {
+    if (!PyObject_IsInstance(ast, (PyObject*)mod_type)) {
         PyErr_SetString(PyExc_TypeError, "expected either Module, Interactive "
                         "or Expression node");
         return NULL;