diff -r d4de90a612f7 -r 58c497d0e44d mercurial/context.py
--- a/mercurial/context.py	Tue Feb 15 22:25:48 2011 +0100
+++ b/mercurial/context.py	Thu Feb 03 10:31:17 2011 +0100
@@ -722,7 +722,8 @@
 
     def tags(self):
         t = []
-        [t.extend(p.tags()) for p in self.parents()]
+        for p in self.parents():
+            t.extend(p.tags())
         return t
 
     def children(self):