error[E0658]: `log_syntax!` is not stable enough for use and is subject to change (see issue #29598) --> $DIR/feature-gate-log_syntax.rs:12:5 | LL | log_syntax!() //~ ERROR `log_syntax!` is not stable enough | ^^^^^^^^^^^^^ | = help: add #![feature(log_syntax)] to the crate attributes to enable error: aborting due to previous error For more information about this error, try `rustc --explain E0658`.