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README.OpenSource修改 Created-by: dragonswordy Commit-by: ljy9810 Merged-by: openharmony_ci Description: ### 一、内容说明(相关的Issue) https://gitcode.com/openharmony/third_party_rust_unicode-ident/issues/3 ### 二、建议测试周期和提测地址 建议测试完成时间:xxxx.xx.xx 投产上线时间:xxxx.xx.xx 提测地址:CI环境/压测环境 测试账号: ### 三、变更内容 * 3.1 关联PR列表 * 3.2 数据库和部署说明 1. 常规更新 2. 重启unicorn 3. 重启sidekiq 4. 迁移任务:是否有迁移任务,没有写 "无" 5. rake脚本:`bundle exec xxx RAILS_ENV = production`;没有写 "无" * 3.4 其他技术优化内容(做了什么,变更了什么) - 重构了 xxxx 代码 - xxxx 算法优化 * 3.5 废弃通知(什么字段、方法弃用?) * 3.6 后向不兼容变更(是否有无法向后兼容的变更?) ### 四、研发自测点(自测哪些?冒烟用例全部自测?) 自测测试结论: ### 五、测试关注点(需要提醒QA重点关注的、可能会忽略的地方) 检查点: | 需求名称 | 是否影响xx公共模块 | 是否需要xx功能 | 需求升级是否依赖其他子产品 | |------|------------|----------|---------------| | xxx | 否 | 需要 | 不需要 | | | | | | 接口测试: 性能测试: 并发测试: 其他: See merge request: openharmony/third_party_rust_memoffset!11
memoffset
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+)offset_of_union!for obtaining the offset of a member of a union.span_of!for obtaining the range that a field, or fields, span.
memoffset works under no_std environments.
If you're using a rustc version greater or equal to 1.77, this crate's offset_of!() macro simply forwards to core::mem::offset_of!().
Usage
Add the following dependency to your Cargo.toml:
[dependencies]
memoffset = "0.9"
These versions will compile fine with rustc versions greater or equal to 1.19.
Examples
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);
}
Usage in constants
memoffset has support for compile-time offset_of! on rust>=1.65.
On versions below 1.77, this is an incomplete implementation with one caveat:
Due to dependence on #![feature(const_refs_to_cell)], you cannot get the offset of a Cell field in a const-context.
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