//@ aux-build:unstable_feature.rs //@ revisions: pass fail //@[pass] check-pass #![cfg_attr(pass, feature(feat_bar))] extern crate unstable_feature; use unstable_feature::{Foo, Bar}; /// #[feature(..)] is required to use unstable impl. fn main() { Bar::foo(); //[fail]~^ ERROR: use of unstable library feature `feat_bar` [E0658] }