commit | a347f248d286dd1743c719b31c3f26522d5821a6 | [log] [tgz] |
---|---|---|
author | Treehugger Robot <treehugger-gerrit@google.com> | Mon Dec 19 13:07:17 2022 +0000 |
committer | Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> | Mon Dec 19 13:07:17 2022 +0000 |
tree | 579e9f3356eaf9c19b7f8ebb8619cdb44bc97aa8 | |
parent | f2b9410a8415c62a6214ae6e0e1c2806862d742c [diff] | |
parent | 9713804664dbfecf14b1329382458f7a2d7a11f0 [diff] |
Merge "Upgrade memoffset to 0.7.1" am: 9713804664 Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/memoffset/+/2345764 Change-Id: Ie9592715d91205641d9a1eebc301e60c62e79f7a Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
C-Like offset_of
functionality for Rust structs.
Introduces the following macros:
offset_of!
for obtaining the offset of a member of a struct.offset_of_tuple!
for obtaining the offset of a member of a tuple. (Requires Rust 1.20+)span_of!
for obtaining the range that a field, or fields, span.memoffset
works under no_std
environments.
Add the following dependency to your Cargo.toml
:
[dependencies] memoffset = "0.7"
These versions will compile fine with rustc versions greater or equal to 1.19.
use memoffset::{offset_of, span_of}; #[repr(C, packed)] struct Foo { a: u32, b: u32, c: [u8; 5], d: u32, } fn main() { assert_eq!(offset_of!(Foo, b), 4); assert_eq!(offset_of!(Foo, d), 4+4+5); assert_eq!(span_of!(Foo, a), 0..4); assert_eq!(span_of!(Foo, a .. c), 0..8); assert_eq!(span_of!(Foo, a ..= c), 0..13); assert_eq!(span_of!(Foo, ..= d), 0..17); assert_eq!(span_of!(Foo, b ..), 4..17); }
memoffset
has experimental support for compile-time offset_of!
on a nightly compiler.
In order to use it, you must enable the unstable_const
crate feature and several compiler features.
Cargo.toml:
[dependencies.memoffset] version = "0.7" features = ["unstable_const"]
Your crate root: (lib.rs
/main.rs
)
#![feature(const_ptr_offset_from, const_refs_to_cell)]