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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-30 18:31:44 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-30 18:31:44 +0000 |
| commit | c23a457e72abe608715ac76f076f47dc42af07a5 (patch) | |
| tree | 2772049aaf84b5c9d0ed12ec8d86812f7a7904b6 /library/core/src/num/nonzero.rs | |
| parent | Releasing progress-linux version 1.73.0+dfsg1-1~progress7.99u1. (diff) | |
| download | rustc-c23a457e72abe608715ac76f076f47dc42af07a5.tar.xz rustc-c23a457e72abe608715ac76f076f47dc42af07a5.zip | |
Merging upstream version 1.74.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'library/core/src/num/nonzero.rs')
| -rw-r--r-- | library/core/src/num/nonzero.rs | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs index 5939dedbd..7f8d673c1 100644 --- a/library/core/src/num/nonzero.rs +++ b/library/core/src/num/nonzero.rs @@ -41,6 +41,20 @@ macro_rules! nonzero_integers { /// with the exception that `0` is not a valid instance. #[doc = concat!("`Option<", stringify!($Ty), ">` is guaranteed to be compatible with `", stringify!($Int), "`,")] /// including in FFI. + /// + /// Thanks to the [null pointer optimization], + #[doc = concat!("`", stringify!($Ty), "` and `Option<", stringify!($Ty), ">`")] + /// are guaranteed to have the same size and alignment: + /// + /// ``` + /// # use std::mem::{size_of, align_of}; + #[doc = concat!("use std::num::", stringify!($Ty), ";")] + /// + #[doc = concat!("assert_eq!(size_of::<", stringify!($Ty), ">(), size_of::<Option<", stringify!($Ty), ">>());")] + #[doc = concat!("assert_eq!(align_of::<", stringify!($Ty), ">(), align_of::<Option<", stringify!($Ty), ">>());")] + /// ``` + /// + /// [null pointer optimization]: crate::option#representation #[$stability] #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)] #[repr(transparent)] |