diff --git a/include/utils/RefBase.h b/include/utils/RefBase.h
index f8c3216..ca17082 100644
--- a/include/utils/RefBase.h
+++ b/include/utils/RefBase.h
@@ -119,6 +119,7 @@
     // used to override the RefBase destruction.
     class Destroyer {
         friend class RefBase;
+        friend class weakref_type;
     public:
         virtual ~Destroyer();
     private: