diff --git a/loopy/auto_test.py b/loopy/auto_test.py
index 6a4d559758bc1d7ca52e9dc4da1b7e503e22cc29..56ed87176f891d362ac0555024ef0d8098cd843e 100644
--- a/loopy/auto_test.py
+++ b/loopy/auto_test.py
@@ -518,9 +518,13 @@ def auto_test_vs_ref(
 
     args = None
     from loopy.kernel import kernel_state
+    from loopy.target.pyopencl import PyOpenCLTarget
     if test_knl.state not in [
             kernel_state.PREPROCESSED,
             kernel_state.SCHEDULED]:
+        if isinstance(test_knl.target, PyOpenCLTarget):
+            test_knl = test_knl.copy(target=PyOpenCLTarget(ctx.devices[0]))
+
         test_knl = lp.preprocess_kernel(test_knl)
 
     if not test_knl.schedule: