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/Modules/mmapmodule.c b/Modules/mmapmodule.c
index 6a2ebfd..034bd22 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -930,7 +930,7 @@
 	0,					/* tp_print */
 	0,					/* tp_getattr */
 	0,					/* tp_setattr */
-	0,					/* tp_compare */
+	0,					/* tp_reserved */
 	0,					/* tp_repr */
 	0,					/* tp_as_number */
 	&mmap_as_sequence,			/*tp_as_sequence*/