error[E0658]: use of unstable library feature 'function' --> $DIR/internal-unstable-thread-local.rs:19:32 | LL | thread_local!(static BAR: () = internal_unstable::unstable()); //~ ERROR use of unstable | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = help: add #![feature(function)] to the crate attributes to enable error: aborting due to previous error For more information about this error, try `rustc --explain E0658`.