diff --git a/src/libstd/num/f32.rs b/src/libstd/num/f32.rs
index b8a70d756ef..9d0b9c3bbb4 100644
--- a/src/libstd/num/f32.rs
+++ b/src/libstd/num/f32.rs
@@ -14,7 +14,6 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![allow(missing_docs)]
-#![allow(unsigned_negation)]
 
 use prelude::v1::*;