Remove lint annotations in specific crates that are already enforced by rustbuild

Remove some random unnecessary lint `allow`s

3 files changed, 6 insertions, 3 deletions

diff --git a/src/bootstrap/bin/main.rs b/src/bootstrap/bin/main.rs
index 0732cb83f39..da35c971f97 100644
--- a/src/bootstrap/bin/main.rs
+++ b/src/bootstrap/bin/main.rs
@@ -5,7 +5,8 @@
 //! parent directory, and otherwise documentation can be found throughout the `build`
 //! directory in each respective module.
 
-#![deny(warnings)]
+// NO-RUSTC-WRAPPER
+#![deny(warnings, rust_2018_idioms)]
 
 use std::env;
 
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index a9225f2870f..3888d0ef627 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -15,7 +15,8 @@
 //! switching compilers for the bootstrap and for build scripts will probably
 //! never get replaced.
 
-#![deny(warnings)]
+// NO-RUSTC-WRAPPER
+#![deny(warnings, rust_2018_idioms)]
 
 use std::env;
 use std::ffi::OsString;
diff --git a/src/bootstrap/bin/rustdoc.rs b/src/bootstrap/bin/rustdoc.rs
index 1c9f6e1ab28..057daaf2dc4 100644
--- a/src/bootstrap/bin/rustdoc.rs
+++ b/src/bootstrap/bin/rustdoc.rs
@@ -2,7 +2,8 @@
 //!
 //! See comments in `src/bootstrap/rustc.rs` for more information.
 
-#![deny(warnings)]
+// NO-RUSTC-WRAPPER
+#![deny(warnings, rust_2018_idioms)]
 
 use std::env;
 use std::process::Command;