Issue #1717: rename tp_compare to tp_reserved.  I'll change the
type of tp_compare in a separate commit, for ease of reversion
should things go wrong.
diff --git a/Python/traceback.c b/Python/traceback.c
index 42bbd53..e77b1b2 100644
--- a/Python/traceback.c
+++ b/Python/traceback.c
@@ -72,7 +72,7 @@
 	0,		/*tp_print*/
 	0,    /*tp_getattr*/
 	0,		/*tp_setattr*/
-	0,		/*tp_compare*/
+	0,		/*tp_reserved*/
 	0,		/*tp_repr*/
 	0,		/*tp_as_number*/
 	0,		/*tp_as_sequence*/