diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index 1138258..e8881dc 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -234,7 +234,7 @@
 #include "testcapi_long.h"
 
 static PyObject *
-test_longlong_api(PyObject* self)
+test_longlong_api(PyObject* self, PyObject *args)
 {
 	return TESTNAME(raise_test_longlong_error);
 }