diff --git a/src/lisp/lcp-test.lisp b/src/lisp/lcp-test.lisp
index bf88720c0..69e4b9662 100644
--- a/src/lisp/lcp-test.lisp
+++ b/src/lisp/lcp-test.lisp
@@ -964,4 +964,7 @@
       (single-member-test (member "CopyableClass2")
                           "object.member_ = member_;")
       (single-member-test (member "UnknownClass")
-                         "object.member_ = member_;"))))
+                          "object.member_ = member_;")
+      (undefine-cpp-types))))
+
+