| // SPDX-License-Identifier: GPL-2.0 |
| //! This crate provides a [const function][const-functions] `build_error`, which will panic in |
| //! compile-time if executed in [const context][const-context], and will cause a build error |
| //! if not executed at compile time and the optimizer does not optimise away the call. |
| //! It is used by `build_assert!` in the kernel crate, allowing checking of |
| //! conditions that could be checked statically, but could not be enforced in |
| //! Rust yet (e.g. perform some checks in [const functions][const-functions], but those |
| //! functions could still be called in the runtime). |
| //! For details on constant evaluation in Rust, please see the [Reference][const-eval]. |
| //! [const-eval]: https://doc.rust-lang.org/reference/const_eval.html |
| //! [const-functions]: https://doc.rust-lang.org/reference/const_eval.html#const-functions |
| //! [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context |
| /// Panics if executed in [const context][const-context], or triggers a build error if not. |
| /// [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context |
| #[export_name = "rust_build_error"] |
| pub const fn build_error(msg: &'static str) -> ! { |