diff --git a/Include/intobject.h b/Include/intobject.h
index 558bd76e640..d9fd68f3eee 100644
--- a/Include/intobject.h
+++ b/Include/intobject.h
@@ -63,6 +63,7 @@ extern DL_IMPORT(PyTypeObject) PyInt_Type;
 
 extern PyObject *PyInt_FromLong Py_PROTO((long));
 extern long PyInt_AsLong Py_PROTO((PyObject *));
+extern long PyInt_GetMax Py_PROTO((void));
 
 
 /*