diff --git a/src/lib/diff/gen-node.hpp b/src/lib/diff/gen-node.hpp
index e14944585..3ad0a574a 100644
--- a/src/lib/diff/gen-node.hpp
+++ b/src/lib/diff/gen-node.hpp
@@ -844,7 +844,7 @@ namespace diff{
   inline GenNode
   Rec::buildAttribute (string const& key, X&& payload)
   {
-    return GenNode(key, payload);
+    return GenNode(key, std::forward<X>(payload));
   }