Issue #1445: Fix a SystemError when accessing the ``cell_contents``
attribute of an empty cell object.  Now a ValueError is raised.
diff --git a/Lib/test/test_funcattrs.py b/Lib/test/test_funcattrs.py
index 7a083b7..a32be38 100644
--- a/Lib/test/test_funcattrs.py
+++ b/Lib/test/test_funcattrs.py
@@ -242,6 +242,17 @@
     verify(c[0].__class__.__name__ == "cell") # don't have a type object handy
     cantset(f, "func_closure", c)
 
+def test_empty_cell():
+    def f(): print a
+    try:
+        f.func_closure[0].cell_contents
+    except ValueError:
+        pass
+    else:
+        raise TestFailed, "shouldn't be able to read an empty cell"
+
+    a = 12
+
 def test_func_doc():
     def f(): pass
     verify(f.__doc__ is None)
@@ -385,6 +396,7 @@
 
 def testmore():
     test_func_closure()
+    test_empty_cell()
     test_func_doc()
     test_func_globals()
     test_func_name()