diff --git a/AsyncDisplayKit/Private/ASWeakSet.m b/AsyncDisplayKit/Private/ASWeakSet.m
index a8b8ce1893..38fa1be051 100644
--- a/AsyncDisplayKit/Private/ASWeakSet.m
+++ b/AsyncDisplayKit/Private/ASWeakSet.m
@@ -26,7 +26,7 @@
 
 - (void)addObject:(id)object
 {
-  [_mapTable setObject:kCFNull forKey:object];
+  [_mapTable setObject:(NSNull *)kCFNull forKey:object];
 }
 
 - (void)removeObject:(id)object