diff --git a/src/tencent_cos.h b/src/tencent_cos.h
index 94842ba..a74b23e 100644
--- a/src/tencent_cos.h
+++ b/src/tencent_cos.h
@@ -15,6 +15,7 @@ namespace module
 		// 通过 imodule 继承
 		virtual void regist_global(const char* name, sol::state* lua);
 		virtual void delete_global() { delete this; }
+		virtual void self_free() {}
 	};
 }