Issue 5794: fix cPickle's unpickling of recursive tuples.
diff --git a/Lib/test/test_cpickle.py b/Lib/test/test_cpickle.py
index 0541873..c240669 100644
--- a/Lib/test/test_cpickle.py
+++ b/Lib/test/test_cpickle.py
@@ -65,6 +65,11 @@
                           AbstractPickleTests.test_recursive_list,
                           self)
 
+    def test_recursive_tuple(self):
+        self.assertRaises(ValueError,
+                          AbstractPickleTests.test_recursive_tuple,
+                          self)
+
     def test_recursive_inst(self):
         self.assertRaises(ValueError,
                           AbstractPickleTests.test_recursive_inst,