rust/kernel/static_assert.rs

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 //! Static assert.
   4
   5 /// Static assert (i.e. compile-time assert).
   6 ///
   7 /// Similar to C11 [`_Static_assert`] and C++11 [`static_assert`].
   8 ///
   9 /// The feature may be added to Rust in the future: see [RFC 2790].
  10 ///
  11 /// [`_Static_assert`]: https://en.cppreference.com/w/c/language/_Static_assert
  12 /// [`static_assert`]: https://en.cppreference.com/w/cpp/language/static_assert
  13 /// [RFC 2790]: https://github.com/rust-lang/rfcs/issues/2790
  14 ///
  15 /// # Examples
  16 ///
  17 /// ```
  18 /// static_assert!(42 > 24);
  19 /// static_assert!(core::mem::size_of::<u8>() == 1);
  20 ///
  21 /// const X: &[u8] = b"bar";
  22 /// static_assert!(X[1] == b'a');
  23 ///
  24 /// const fn f(x: i32) -> i32 {
  25 ///     x + 2
  26 /// }
  27 /// static_assert!(f(40) == 42);
  28 /// ```
  29 #[macro_export]
  30 macro_rules! static_assert {
  31     ($condition:expr) => {
  32         const _: () = core::assert!($condition);
  33     };
  34 }