error[E0658]: #[optimize] attribute is an unstable feature (see issue #54882) --> $DIR/feature-gate-optimize_attribute.rs:7:1 | LL | #[optimize(size)] | ^^^^^^^^^^^^^^^^^ | = help: add #![feature(optimize_attribute)] to the crate attributes to enable error[E0658]: #[optimize] attribute is an unstable feature (see issue #54882) --> $DIR/feature-gate-optimize_attribute.rs:10:1 | LL | #[optimize(speed)] | ^^^^^^^^^^^^^^^^^^ | = help: add #![feature(optimize_attribute)] to the crate attributes to enable error[E0658]: #[optimize] attribute is an unstable feature (see issue #54882) --> $DIR/feature-gate-optimize_attribute.rs:13:1 | LL | #[optimize(banana)] | ^^^^^^^^^^^^^^^^^^^ | = help: add #![feature(optimize_attribute)] to the crate attributes to enable error[E0658]: #[optimize] attribute is an unstable feature (see issue #54882) --> $DIR/feature-gate-optimize_attribute.rs:4:1 | LL | #[optimize(size)] | ^^^^^^^^^^^^^^^^^ | = help: add #![feature(optimize_attribute)] to the crate attributes to enable error[E0658]: #[optimize] attribute is an unstable feature (see issue #54882) --> $DIR/feature-gate-optimize_attribute.rs:2:1 | LL | #![optimize(speed)] | ^^^^^^^^^^^^^^^^^^^ | = help: add #![feature(optimize_attribute)] to the crate attributes to enable error[E0722]: invalid argument --> $DIR/feature-gate-optimize_attribute.rs:13:12 | LL | #[optimize(banana)] | ^^^^^^ error: aborting due to 6 previous errors Some errors occurred: E0658, E0722. For more information about an error, try `rustc --explain E0658`.