--- a/mercurial/fileset.py	Tue Jan 15 02:59:12 2013 +0100
+++ b/mercurial/fileset.py	Wed Dec 12 02:38:14 2012 +0100
@@ -373,7 +373,7 @@
     # i18n: "subrepo" is a keyword
     getargs(x, 0, 1, _("subrepo takes at most one argument"))
     ctx = mctx.ctx
-    sstate = ctx.substate
+    sstate = sorted(ctx.substate)
     if x:
         pat = getstring(x, _("subrepo requires a pattern or no arguments"))