diff --git a/interop/src/cpp/DeserializerBase.h b/interop/src/cpp/DeserializerBase.h
index 7f62a8768b5b73acca635d776a24f49e0eb08eb2..2cc78c1c1f5f2f8062ced18672195992d8538a82 100644
--- a/interop/src/cpp/DeserializerBase.h
+++ b/interop/src/cpp/DeserializerBase.h
@@ -360,7 +360,7 @@ public:
     }
     fprintf(stderr, "Unsupported custom deserialization for %s\n", kind.c_str());
     auto tag = readTag();
-    assert(tag == INTEROP_TAG_UNDEFINED);
+    if (tag == INTEROP_TAG_UNDEFINED) INTEROP_FATAL("Undefined interop tag");
     // Skip updefined tag!.
     InteropCustomObject result;
     strcpy(result.kind, "Error");
diff --git a/interop/src/cpp/ets/convertors-ets.cc b/interop/src/cpp/ets/convertors-ets.cc
index d6f66171c61f3c7aac42a83ba8c2eaef3cdecde8..5967f0e0fb0e4de3f26edad66e0112d7fb915d76 100644
--- a/interop/src/cpp/ets/convertors-ets.cc
+++ b/interop/src/cpp/ets/convertors-ets.cc
@@ -56,7 +56,6 @@ static bool registerNatives(ets_env *env, const ets_class clazz, const std::vect
 
 bool registerAllModules(ets_env *env) {
     auto moduleNames = EtsExports::getInstance()->getModules();
-    ets_class defaultNativeModule = env->FindClass(nativeModule);
 
     for (auto it = moduleNames.begin(); it != moduleNames.end(); ++it) {
         std::string classpath = EtsExports::getInstance()->getClasspath(*it);