diff --git a/artiq/test/lit/codegen/custom_comparison.py b/artiq/test/lit/codegen/custom_comparison.py
new file mode 100644
index 000000000..8a7a1d32b
--- /dev/null
+++ b/artiq/test/lit/codegen/custom_comparison.py
@@ -0,0 +1,13 @@
+# RUN: %python -m artiq.compiler.testbench.signature +diag %s >%t
+# RUN: OutputCheck %s --file-to-check=%t
+
+class Foo:
+    def __init__(self):
+        pass
+
+a = Foo()
+b = Foo()
+
+# CHECK-L: ${LINE:+1}: error: Custom object comparison is not supported
+a > b
+
diff --git a/artiq/test/lit/codegen/custom_inclusion.py b/artiq/test/lit/codegen/custom_inclusion.py
new file mode 100644
index 000000000..92cd1a772
--- /dev/null
+++ b/artiq/test/lit/codegen/custom_inclusion.py
@@ -0,0 +1,13 @@
+# RUN: %python -m artiq.compiler.testbench.signature +diag %s >%t
+# RUN: OutputCheck %s --file-to-check=%t
+
+class Foo:
+    def __init__(self):
+        pass
+
+a = Foo()
+b = Foo()
+
+# CHECK-L: ${LINE:+1}: error: Custom object inclusion test is not supported
+a in b
+