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Add an AtomicCell abstraction #62577
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(rust_highfive has picked a reviewer for you, use r? to override) |
@@ -271,6 +322,8 @@ cfg_if! { | |||
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pub use std::sync::atomic::{AtomicBool, AtomicUsize, AtomicU32, AtomicU64}; | |||
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pub use crossbeam_utils::atomic::AtomicCell; |
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I don't get why you define the struct AtomicCell
above but then use it from the crossbeam_utils? Are they different? What is the purpose of including AtomicCell from crossbeam_utils here?
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In general, this code defines a unified set of structures related to multi-threadiness(?) with a caveat - the definitions are different for parallel_compiler
cfg.
If you expand the omitted lines in the diff, you can see that the pub struct AtomicCell<T: Copy>(Cell<T>);
(which is mainly a wrapper around Cell<T>
, which isn't really atomic nor should it be in single-threaded case) is defined manually in the #[cfg(not(parallel_compiler))]
branch.
Otherwise, if we build a parallel compiler, we just re-export crossbeam_utils::atomic::AtomicCell
instead.
@bors r+ |
📌 Commit 498bdc9 has been approved by |
Add an AtomicCell abstraction Split out from rust-lang#61923.
Rollup of 5 pull requests Successful merges: - #62577 (Add an AtomicCell abstraction) - #62585 (Make struct_tail normalize when possible) - #62604 (Handle errors during error recovery gracefully) - #62636 (rustbuild: Improve assert about building tools once) - #62651 (Make some rustc macros more hygienic) Failed merges: r? @ghost
Split out from #61923.