diff --git a/python/dune/codegen/pdelab/tensors.py b/python/dune/codegen/pdelab/tensors.py
index 26ef137dd96297f8608522c7e634d8c06bed8748..5a7f48c23aeb8b5451be30a493a5a2312d273dee 100644
--- a/python/dune/codegen/pdelab/tensors.py
+++ b/python/dune/codegen/pdelab/tensors.py
@@ -17,7 +17,7 @@ import itertools as it
 
 
 def define_determinant(name, matrix, shape, visitor):
-    temporary_variable(name)
+    temporary_variable(name, managed=True)
 
     assert len(shape) == 2 and shape[0] == shape[1]
     dim = shape[0]
@@ -46,7 +46,7 @@ def define_determinant(name, matrix, shape, visitor):
 def define_determinant_inverse(name, matrix, shape, visitor):
     det = name_determinant(matrix, shape, visitor)
 
-    temporary_variable(name)
+    temporary_variable(name, managed=True)
 
     instruction(expression=prim.Quotient(1, prim.Variable(det)),
                 assignee=prim.Variable(name),