diff --git a/lib/spack/spack/__init__.py b/lib/spack/spack/__init__.py
index aee11f061f326b263099a4f13797c916a56c105b..9108e1d0e333d13af55555a4a72416718bbff668 100644
--- a/lib/spack/spack/__init__.py
+++ b/lib/spack/spack/__init__.py
@@ -136,9 +136,7 @@
     # don't add a second username if it's already unique by user.
     if not _tmp_user in path:
         tmp_dirs.append(join_path(path, '%u', 'spack-stage'))
-
-for path in _tmp_candidates:
-    if not path in tmp_dirs:
+    else:
         tmp_dirs.append(join_path(path, 'spack-stage'))
 
 # Whether spack should allow installation of unsafe versions of