diff --git a/com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/nodes/AttributesAccessNodes.java b/com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/nodes/AttributesAccessNodes.java
index 8ab5b1bf94c0021383fd00353586c3ba21292309..1ce91a921d39bd1c33dc932b7a4d26dfccfb24e5 100644
--- a/com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/nodes/AttributesAccessNodes.java
+++ b/com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/nodes/AttributesAccessNodes.java
@@ -130,7 +130,7 @@ public final class AttributesAccessNodes {
                 copyRegAttributes = CopyOfRegAttributesNode.create();
             }
             copyRegAttributes.execute(x, y);
-            return null;
+            return RNull.instance;
         }
 
         @Fallback