mercurial/revset.py

--- a/mercurial/revset.py	Mon Feb 10 22:56:10 2014 +0100
+++ b/mercurial/revset.py	Thu Feb 06 14:57:25 2014 -0800
@@ -334,7 +334,7 @@
         raise error.ParseError(_("~ expects a number"))
     ps = set()
     cl = repo.changelog
-    for r in getset(repo, cl, x):
+    for r in getset(repo, baseset(cl), x):
         for i in range(n):
             r = cl.parentrevs(r)[0]
         ps.add(r)