In file included from crash_on_invalid.cpp:5: ./crash_on_invalid.h:16:30: error: unknown template name 'GarbageCollectedFinalized' class Gamepad final : public GarbageCollectedFinalized, ^ ./crash_on_invalid.h:20:19: error: unknown type name 'WrapperTypeInfo' virtual const WrapperTypeInfo *wrapperTypeInfo() const {} ^ 2 errors generated.