self is dereffed (and passed as first arg), so it's known to be good.
func is returned from PyArg_ParseTuple and also dereffed.

Reported by Klocwork, #30 (self one at least).
diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index ee9a633..640b70f 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -2104,8 +2104,8 @@
 	data = PyMem_NEW(PythonCmd_ClientData, 1);
 	if (!data)
 		return PyErr_NoMemory();
-	Py_XINCREF(self);
-	Py_XINCREF(func);
+	Py_INCREF(self);
+	Py_INCREF(func);
 	data->self = selfptr;
 	data->func = func;