diff --git a/tests/Conformance.test.cpp b/tests/Conformance.test.cpp
index 7d5f41a1..c113ff78 100644
--- a/tests/Conformance.test.cpp
+++ b/tests/Conformance.test.cpp
@@ -1301,9 +1301,12 @@ TEST_CASE("UserdataApi")
     lua_State* L = globalState.get();
 
     // setup dtor for tag 42 (created later)
-    lua_setuserdatadtor(L, 42, [](lua_State* l, void* data) {
+    auto dtor = [](lua_State* l, void* data) {
         dtorhits += *(int*)data;
-    });
+    };
+    CHECK((void*)lua_getuserdatadtor(L, 42) == nullptr); // (void*) silences warning C4180 on VS 2017
+    lua_setuserdatadtor(L, 42, dtor);
+    CHECK((void*)lua_getuserdatadtor(L, 42) == dtor);    
 
     // light user data
     int lud;