#![feature(assert_matches)]
#![feature(associated_type_bounds)]
#![feature(exhaustive_patterns)]
-#![feature(let_else)]
+#![cfg_attr(bootstrap, feature(let_else))]
#![feature(min_specialization)]
#![feature(never_type)]
#![feature(rustc_attrs)]
#![feature(step_trait)]
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
use std::iter::FromIterator;
use std::path::{Path, PathBuf};