1 error[E0658]: `concat_idents` is not stable enough for use and is subject to change (see issue #29599)
2 --> $DIR/feature-gate-concat_idents3.rs:17:20
4 LL | assert_eq!(10, concat_idents!(X, Y_1)); //~ ERROR `concat_idents` is not stable
5 | ^^^^^^^^^^^^^^^^^^^^^^
7 = help: add #![feature(concat_idents)] to the crate attributes to enable
9 error[E0658]: `concat_idents` is not stable enough for use and is subject to change (see issue #29599)
10 --> $DIR/feature-gate-concat_idents3.rs:18:20
12 LL | assert_eq!(20, concat_idents!(X, Y_2)); //~ ERROR `concat_idents` is not stable
13 | ^^^^^^^^^^^^^^^^^^^^^^
15 = help: add #![feature(concat_idents)] to the crate attributes to enable
17 error: aborting due to 2 previous errors
19 For more information about this error, try `rustc --explain E0658`.