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/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 262a7d0..0db13b1 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -4566,7 +4566,7 @@
     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*/
@@ -9493,7 +9493,7 @@
     0,                  /* tp_print */
     0,                  /* tp_getattr */
     0,                  /* tp_setattr */
-    0,                  /* tp_compare */
+    0,                  /* tp_reserved */
     unicode_repr,           /* tp_repr */
     &unicode_as_number,         /* tp_as_number */
     &unicode_as_sequence,       /* tp_as_sequence */
@@ -9799,7 +9799,7 @@
     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 */