diff -r 39f519be5e65 -r 56e15db9109f mercurial/subrepo.py
--- a/mercurial/subrepo.py	Wed Apr 15 11:23:26 2015 -0400
+++ b/mercurial/subrepo.py	Wed Apr 15 11:49:44 2015 -0400
@@ -959,6 +959,13 @@
         """
         return self._repo.wvfs
 
+    @propertycache
+    def _relpath(self):
+        """return path to this subrepository as seen from outermost repository
+        """
+        # Keep consistent dir separators by avoiding vfs.join(self._path)
+        return reporelpath(self._repo)
+
 class svnsubrepo(abstractsubrepo):
     def __init__(self, ctx, path, state):
         super(svnsubrepo, self).__init__(ctx, path)