overly strict semantics

Posted Jan 15, 2026 0:18 UTC (Thu) by milesrout (subscriber, #126894)
In reply to: overly strict semantics by joib
Parent article: READ_ONCE(), WRITE_ONCE(), but not for Rust

The worst part of the design is _Atomic/std::atomic. Atomic operations are atomic *operations, the operations are atomic. There is nothing inherently atomic or non-atomic about the operands themselves. The operator overloading is also a plain bad idea.

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overly strict semantics

Posted Jan 15, 2026 15:40 UTC (Thu) by bertschingert (subscriber, #160729) [Link]

The GCC atomic intrinsics seem to get this right. I'm not sure if there's a portable way to do atomic operations on regular int types, though.

OTOH, what I like about the Rust (and C/C++11?) atomics is that the type system prevents accidentally introducing data races because you can't do a non-atomic load/store to an atomic type -- at least without unsafe code. Given that the article mentions there are cases in C where READ_ONCE() and WRITE_ONCE() should have been used, but weren't, this seems to be a real risk.