diff --git a/lib.rs b/lib.rs
index 5656588..2ee7bea 100644
--- a/lib.rs
+++ b/lib.rs
@@ -46,8 +46,8 @@
 #![deny(warnings)]
 #![forbid(unsafe_code)]
 
-#![feature(i128_type)]
 #![cfg_attr(stage0, feature(slice_patterns))]
+#![cfg_attr(stage0, feature(i128_type))]
 #![feature(try_from)]
 
 // See librustc_cratesio_shim/Cargo.toml for a comment explaining this.
diff --git a/tests/ieee.rs b/tests/ieee.rs
index ff46ee7..627d797 100644
--- a/tests/ieee.rs
+++ b/tests/ieee.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![feature(i128_type)]
+#![cfg_attr(stage0, feature(i128_type))]
 
 #[macro_use]
 extern crate rustc_apfloat;