Avoid unnecessary synchronization in `{force,deref}_mut`

matklad / once_cell

Rust library for single assignment cells and lazy statics without macros

Apache License 2.0

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Avoid unnecessary synchronization in `{force,deref}_mut` #231

Closed danielhenrymantilla closed 1 year ago

danielhenrymantilla commented 1 year ago

DerefMut was not delegating to force_mut() (contary to the by-ref APIs);
Lazy::force_mut was not taking advantage of exclusive-mutability access, and instead paying shared-mutability access. Mainly, in the sync case, it involved atomic operations which are now skipped.

Fixes #226

matklad commented 1 year ago

Could you bump a patch version in Cargo.toml and add a short note to the Changelog?

matklad commented 1 year ago

bors d+

bors[bot] commented 1 year ago

:v: danielhenrymantilla can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

danielhenrymantilla commented 1 year ago

@matklad I won't approve the PR myself since I have also taken the liberty to add a Cargo.lock.msrv check (while also updating it), which you may want to review 🙂

(I'll admit I could have opened another PR for that xtask tweak commit; I'm taking a shortcut here)

matklad commented 1 year ago

bors r+

bors[bot] commented 1 year ago

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Rust