Disallow keyword arguments for type constructors that don't use them.
(fixes bug #1119418)
diff --git a/Objects/sliceobject.c b/Objects/sliceobject.c
index c37af2b..f5ed898 100644
--- a/Objects/sliceobject.c
+++ b/Objects/sliceobject.c
@@ -174,6 +174,9 @@
 
 	start = stop = step = NULL;
 
+	if (!_PyArg_NoKeywords("slice()", kw))
+		return NULL;
+
 	if (!PyArg_UnpackTuple(args, "slice", 1, 3, &start, &stop, &step))
 		return NULL;