commit e4495877dd08b4d0568bb8a75ae5c69b3d91ff60
author Raymond Hettinger <python@rcn.com> Tue Dec 15 00:42:30 2015 -0800
committer Raymond Hettinger <python@rcn.com> Tue Dec 15 00:42:30 2015 -0800
tree 92647049484165899a897f5ee561dbdd6e5991f2
parent f4f67e52b4bdab792e111ba024ddd223f24909df

Minor tweek.  Counting down rather than up reduces register pressure.

Objects/setobject.c

diff --git a/Objects/setobject.c b/Objects/setobject.c
index 4723b58..45aa200 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -678,7 +678,7 @@
         size_t newmask = (size_t)so->mask;
         so->fill = other->used;
         so->used = other->used;
-        for (i = 0; i <= other->mask; i++, other_entry++) {
+        for (i = other->mask + 1; i > 0 ; i--, other_entry++) {
             key = other_entry->key;
             if (key != NULL && key != dummy) {
                 Py_INCREF(key);