diff --git a/rust-version b/rust-version
index 7a16560006..0c2bc318c6 100644
--- a/rust-version
+++ b/rust-version
@@ -1 +1 @@
-nightly-2018-12-21
+nightly-2018-12-22
diff --git a/tests/compile-fail/never_transmute_void.rs b/tests/compile-fail/never_transmute_void.rs
index fab4981047..5993cfad86 100644
--- a/tests/compile-fail/never_transmute_void.rs
+++ b/tests/compile-fail/never_transmute_void.rs
@@ -2,6 +2,7 @@
 // compile-flags: -Zmiri-disable-validation
 
 #![feature(never_type)]
+#![allow(unused)]
 
 enum Void {}