diff --git a/Include/intobject.h b/Include/intobject.h
index d9fd68f..cd66f75 100644
--- a/Include/intobject.h
+++ b/Include/intobject.h
@@ -83,7 +83,7 @@
 #define Py_True ((PyObject *) &_Py_TrueStruct)
 
 /* Macro, trading safety for speed */
-#define PyInt_AS_LONG(op) ((op)->ob_ival)
+#define PyInt_AS_LONG(op) (((PyIntObject *)(op))->ob_ival)
 
 #ifdef __cplusplus
 }