1 files changed, 4 insertions, 2 deletions
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index a2cefe488c6..24892dfcc8f 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -45,18 +45,20 @@
 #![feature(const_fn)]
 #![feature(core_intrinsics)]
 #![feature(drain_filter)]
-#![feature(dyn_trait)]
 #![feature(entry_or_default)]
+#![cfg_attr(stage0, feature(dyn_trait))]
 #![feature(from_ref)]
 #![feature(fs_read_write)]
 #![cfg_attr(windows, feature(libc))]
 #![feature(macro_lifetime_matcher)]
 #![feature(macro_vis_matcher)]
+#![feature(never_type)]
 #![feature(exhaustive_patterns)]
 #![feature(non_exhaustive)]
 #![feature(nonzero)]
 #![feature(proc_macro_internals)]
 #![feature(quote)]
+#![feature(optin_builtin_traits)]
 #![feature(refcell_replace_swap)]
 #![feature(rustc_diagnostic_macros)]
 #![feature(slice_patterns)]
@@ -80,7 +82,7 @@ extern crate graphviz;
 #[macro_use] extern crate lazy_static;
 #[cfg(windows)]
 extern crate libc;
-extern crate rustc_back;
+extern crate rustc_target;
 #[macro_use] extern crate rustc_data_structures;
 extern crate serialize;
 extern crate rustc_const_math;