diff -r c91e7f707562 Objects/typeobject.c
--- a/Objects/typeobject.c	Tue Jul 09 00:49:03 2013 +0200
+++ b/Objects/typeobject.c	Tue Jul 09 01:58:56 2013 +0200
@@ -5279,7 +5279,7 @@ slot_tp_str(PyObject *self)
         Py_DECREF(func);
         return res;
     }
-    else {
+    else if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
         /* PyObject *ress; */
         PyErr_Clear();
         res = slot_tp_repr(self);
@@ -5296,6 +5296,9 @@ slot_tp_str(PyObject *self)
         return ress;
         */
     }
+    else {
+        return NULL;
+    }
 }
 
 static Py_hash_t