Auto merge of #912 - RalfJung:rustup, r=RalfJung

fix test failure due to my own lint

Author: bors

rust-version

@@ -1 +1 @@
-2111aed0a38c819acb140c7153e9366964a37f2f
+ef1ecbefb8719e408150738664d443a73f757ffd

tests/compile-fail/never_transmute_void.rs

@@ -2,7 +2,7 @@
 // compile-flags: -Zmiri-disable-validation
 
 #![feature(never_type)]
-#![allow(unused)]
+#![allow(unused, invalid_value)]
 
 enum Void {}