error: attribute should be applied to a function definition --> $DIR/issue-68060.rs:4:13 | LL | #[target_feature(enable = "")] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ... LL | |_| (), | ------ not a function definition error: the feature named `` is not valid for this target --> $DIR/issue-68060.rs:4:30 | LL | #[target_feature(enable = "")] | ^^^^^^^^^^^ `` is not valid for this target error[E0658]: `#[track_caller]` on closures is currently unstable --> $DIR/issue-68060.rs:8:13 | LL | #[track_caller] | ^^^^^^^^^^^^^^^ | = note: see issue #87417 for more information = help: add `#![feature(closure_track_caller)]` to the crate attributes to enable error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0658`.