diff -r 127281884959 -r 08e1baf924ca mercurial/copies.py
--- a/mercurial/copies.py	Wed Apr 22 00:56:06 2009 +0200
+++ b/mercurial/copies.py	Wed Apr 22 00:57:28 2009 +0200
@@ -160,12 +160,12 @@
     for f in u2:
         checkcopies(f, m2, m1)
 
-    diverge2 = {}
+    diverge2 = set()
     for of, fl in diverge.items():
         if len(fl) == 1:
             del diverge[of] # not actually divergent
         else:
-            diverge2.update(dict.fromkeys(fl)) # reverse map for below
+            diverge2.update(fl) # reverse map for below
 
     if fullcopy:
         repo.ui.debug(_("  all copies found (* = to merge, ! = divergent):\n"))