Benjamin Peterson's patch to fix bug 3661, sys.call_tracing segfaults.
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 5c1a8e9..a8c19ee 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -166,6 +166,9 @@
             self.assert_(isinstance(v[3], int))
             self.assert_(isinstance(v[4], str))
 
+    def test_call_tracing(self):
+        self.assertRaises(TypeError, sys.call_tracing, type, 2)
+
     def test_dlopenflags(self):
         if hasattr(sys, "setdlopenflags"):
             self.assert_(hasattr(sys, "getdlopenflags"))