| error[E0658]: declaration of a non-standard `#[main]` function may change over time, for now a top-level `fn main()` is required | |
| --> $DIR/feature-gate-main.rs:2:1 | |
| | | |
| LL | fn foo() {} | |
| | ^^^^^^^^^^^ | |
| | | |
| = note: see issue #29634 <https://github.com/rust-lang/rust/issues/29634> for more information | |
| = help: add `#![feature(main)]` to the crate attributes to enable | |
| error: aborting due to previous error | |
| For more information about this error, try `rustc --explain E0658`. |