diff -r c56b5b65430d -r 09d5681d5b72 mercurial/ancestor.py
--- a/mercurial/ancestor.py	Wed Nov 21 00:42:05 2012 +0100
+++ b/mercurial/ancestor.py	Wed Nov 28 10:35:12 2012 -0800
@@ -234,7 +234,7 @@
             thisvisit = basesvisit
             othervisit = revsvisit
         else:
-            # not an ancestor of a or b: ignore
+            # not an ancestor of revs or bases: ignore
             continue
 
         thisvisit.remove(curr)