error[E0658]: inline-const is experimental --> $DIR/feature-gate-inline_const.rs:2:13 | LL | let _ = const { | ^^^^^ | = note: see issue #76001 for more information = help: add `#![feature(inline_const)]` to the crate attributes to enable = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0658`.