diff --git a/loopy/codegen/loop.py b/loopy/codegen/loop.py
index 941d5930978edbc985232fa4161e4bb9061672e1..1a132049731cd094ba5665857f1afa4f9b04684a 100644
--- a/loopy/codegen/loop.py
+++ b/loopy/codegen/loop.py
@@ -90,7 +90,7 @@ def get_slab_decomposition(kernel, iname):
                         iname_rel_aff(space,
                             iname, "<=", upper_bound_aff-upper_incr)))
         else:
-            lower_slab = None
+            upper_slab = None
 
         slabs = []