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/_sre.c b/Modules/_sre.c
index 823dc50..45b92f3 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -2625,7 +2625,7 @@
     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 */
@@ -3635,7 +3635,7 @@
     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 */
@@ -3819,7 +3819,7 @@
     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 */