diff --git a/examples/advection.py b/examples/advection.py
index 0a4e17890..13a9e9dc9 100755
--- a/examples/advection.py
+++ b/examples/advection.py
@@ -190,6 +190,7 @@ def main():
     u = pt.make_placeholder(name="u", shape=(dg_ops.nelements, dg_ops.nnodes),
                             dtype=np.float64)
     result = op.apply(u)
+    result = pt.transform.deduplicate(result)
 
     prog = pt.generate_loopy(result, cl_device=queue.device)
     print(prog.program)
diff --git a/pytato/analysis/__init__.py b/pytato/analysis/__init__.py
index 6cbc70620..1213d49af 100644
--- a/pytato/analysis/__init__.py
+++ b/pytato/analysis/__init__.py
@@ -358,16 +358,16 @@ def map_concatenate(self, expr: Concatenate) -> list[ArrayOrNames]:
     def map_einsum(self, expr: Einsum) -> list[ArrayOrNames]:
         return self._get_preds_from_shape(expr.shape) + list(expr.args)
 
+    def map_loopy_call(self, expr: LoopyCall) -> list[ArrayOrNames]:
+        return [ary for ary in expr.bindings.values() if isinstance(ary, Array)]
+
     def map_loopy_call_result(self, expr: NamedArray) -> list[ArrayOrNames]:
         from pytato.loopy import LoopyCall, LoopyCallResult
         assert isinstance(expr, LoopyCallResult)
         assert isinstance(expr._container, LoopyCall)
-        return (
-            self._get_preds_from_shape(expr.shape)
-            + [
-                ary
-                for ary in expr._container.bindings.values()
-                if isinstance(ary, Array)])
+        return [
+            *self._get_preds_from_shape(expr.shape),
+            expr._container]
 
     def _map_index_base(self, expr: IndexBase) -> list[ArrayOrNames]:
         return (
diff --git a/pytato/loopy.py b/pytato/loopy.py
index 9fdb1c338..dbe018d14 100644
--- a/pytato/loopy.py
+++ b/pytato/loopy.py
@@ -96,7 +96,7 @@
 """
 
 
-@array_dataclass()
+@array_dataclass(hash=False)
 class LoopyCall(AbstractResultWithNamedArrays):
     """
     An array expression node representing a call to an entrypoint in a
diff --git a/pytato/transform/__init__.py b/pytato/transform/__init__.py
index 75b7a60f1..aa3bd2838 100644
--- a/pytato/transform/__init__.py
+++ b/pytato/transform/__init__.py
@@ -435,7 +435,7 @@ class CachedMapper(Mapper[ResultT, FunctionResultT, P]):
     """
     def __init__(
             self,
-            err_on_collision: bool = False,
+            err_on_collision: bool = __debug__,
             _cache:
                 CachedMapperCache[ArrayOrNames, ResultT, P] | None = None,
             _function_cache:
@@ -661,8 +661,8 @@ class TransformMapper(CachedMapper[ArrayOrNames, FunctionDefinition, []]):
     """
     def __init__(
             self,
-            err_on_collision: bool = False,
-            err_on_created_duplicate: bool = False,
+            err_on_collision: bool = __debug__,
+            err_on_created_duplicate: bool = __debug__,
             _cache: TransformMapperCache[ArrayOrNames, []] | None = None,
             _function_cache: TransformMapperCache[FunctionDefinition, []] | None = None
             ) -> None:
@@ -756,8 +756,8 @@ class TransformMapperWithExtraArgs(
     """
     def __init__(
             self,
-            err_on_collision: bool = False,
-            err_on_created_duplicate: bool = False,
+            err_on_collision: bool = __debug__,
+            err_on_created_duplicate: bool = __debug__,
             _cache: TransformMapperCache[ArrayOrNames, P] | None = None,
             _function_cache:
                 TransformMapperCache[FunctionDefinition, P] | None = None
@@ -1931,8 +1931,8 @@ def __init__(
             self,
             nsuccessors: Mapping[Array, int],
             _cache: MPMSMaterializerCache | None = None):
-        err_on_collision = False
-        err_on_created_duplicate = False
+        err_on_collision = __debug__
+        err_on_created_duplicate = __debug__
 
         if _cache is None:
             _cache = MPMSMaterializerCache(
diff --git a/test/test_codegen.py b/test/test_codegen.py
index 49bc41bb0..23a5b0f6e 100755
--- a/test/test_codegen.py
+++ b/test/test_codegen.py
@@ -2137,7 +2137,9 @@ def test_zeros_like(ctx_factory):
     assert isinstance(zero, pt.Array)
     assert isinstance(one, pt.Array)
 
-    prg = pt.generate_loopy({"zero": zero, "one": one})
+    prg = pt.generate_loopy(
+        pt.transform.deduplicate(
+            pt.make_dict_of_named_arrays({"zero": zero, "one": one})))
     _, pt_out = prg(cq, x=x_in)
     np.testing.assert_allclose(pt_out["zero"], 0)
     np.testing.assert_allclose(pt_out["one"], 1)