#![deny(warnings)]
#![forbid(unsafe_code)]
-#![feature(const_fn)]
#![feature(i128_type)]
#![feature(slice_patterns)]
#![feature(try_from)]
+#![cfg_attr(stage0, feature(const_fn))]
+#![cfg_attr(not(stage0), feature(const_min_value))]
+#![cfg_attr(not(stage0), feature(const_max_value))]
+
#[macro_use]
extern crate rustc_bitflags;