Rollup merge of rust-lang#58218 - taiki-e:librustc_msan-2018, r=Centril

librustc_msan => 2018

Transitions `librustc_msan` to Rust 2018; cc rust-lang#58099

r? @Centril

Author: kennytm

src/librustc_msan/Cargo.toml

@@ -3,6 +3,7 @@ authors = ["The Rust Project Developers"]
 build = "build.rs"
 name = "rustc_msan"
 version = "0.0.0"
+edition = "2018"
 
 [lib]
 name = "rustc_msan"

src/librustc_msan/build.rs

@@ -1,6 +1,3 @@
-extern crate build_helper;
-extern crate cmake;
-
 use std::env;
 use build_helper::sanitizer_lib_boilerplate;
 

src/librustc_msan/lib.rs

@@ -1,8 +1,9 @@
 #![sanitizer_runtime]
-#![feature(nll)]
 #![feature(sanitizer_runtime)]
 #![feature(staged_api)]
 #![no_std]
 #![unstable(feature = "sanitizer_runtime_lib",
             reason = "internal implementation detail of sanitizers",
             issue = "0")]
+
+#![deny(rust_2018_idioms)]