diff --git a/src/brpc/serialized_response.h b/src/brpc/serialized_response.h
index 4e7d86e..3b33cb2 100644
--- a/src/brpc/serialized_response.h
+++ b/src/brpc/serialized_response.h
@@ -53,7 +53,7 @@ public:
     void Clear() override;
     bool IsInitialized() const override;
     int ByteSize() const;
-    int GetCachedSize() const override { return (int)_serialized.size(); }
+    int GetCachedSize() const PB_422_OVERRIDE { return (int)_serialized.size(); }
     butil::IOBuf& serialized_data() { return _serialized; }
     const butil::IOBuf& serialized_data() const { return _serialized; }
 
@@ -71,7 +71,7 @@ private:
     void MergeFrom(const SerializedResponse& from);
     void SharedCtor();
     void SharedDtor();
-    void SetCachedSize(int size) const override;
+    void SetCachedSize(int size) const PB_422_OVERRIDE;
   
 private:
     butil::IOBuf _serialized;