| The `issue` value is incorrect in a stability attribute. |
| |
| Erroneous code example: |
| |
| ```compile_fail,E0545 |
| #![feature(staged_api)] |
| #![allow(internal_features)] |
| #![stable(since = "1.0.0", feature = "test")] |
| |
| #[unstable(feature = "_unstable_fn", issue = "0")] // invalid |
| fn _unstable_fn() {} |
| |
| #[rustc_const_unstable(feature = "_unstable_const_fn", issue = "0")] // invalid |
| const fn _unstable_const_fn() {} |
| ``` |
| |
| To fix this issue, you need to provide a correct value in the `issue` field. |
| Example: |
| |
| ``` |
| #![feature(staged_api)] |
| #![allow(internal_features)] |
| #![stable(since = "1.0.0", feature = "test")] |
| |
| #[unstable(feature = "_unstable_fn", issue = "none")] // ok! |
| fn _unstable_fn() {} |
| |
| #[rustc_const_unstable(feature = "_unstable_const_fn", issue = "1")] // ok! |
| const fn _unstable_const_fn() {} |
| ``` |
| |
| See the [How Rust is Made and “Nightly Rust”][how-rust-made-nightly] appendix |
| of the Book and the [Stability attributes][stability-attributes] section of the |
| Rustc Dev Guide for more details. |
| |
| [how-rust-made-nightly]: https://doc.rust-lang.org/book/appendix-07-nightly-rust.html |
| [stability-attributes]: https://rustc-dev-guide.rust-lang.org/stability.html |
