diff --git a/pymtl3/passes/testcases/test_cases.py b/pymtl3/passes/testcases/test_cases.py
index fd5603399..8c6351d62 100644
--- a/pymtl3/passes/testcases/test_cases.py
+++ b/pymtl3/passes/testcases/test_cases.py
@@ -3378,7 +3378,8 @@ class ExtSliceComp( Component ):
     def construct( s ):
       @update
       def upblk():
-        42[ 1:2:3, 2:4:6 ]
+        a = None
+        a[ 1:2:3, 2:4:6 ]
   DUT = ExtSliceComp
 
 class CaseAddComponentComp: