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Re:The x86 architecture is the weirdo, part 2 by zozbot234 on Friday April 22, 2022 @11:16AM (#31122641)
Rust has atomic types that can observe races. Such "racy" code is useful because some concurrent code doesn't need the strictest guarantees (sequential consistency). Though, compared to C, Rust does not use the "Consume" memory ordering because so far it has turned out to be ill-defined.
Re:The x86 architecture is the weirdo, part 2 by titzer on Friday April 22, 2022 @11:39AM (#31122967)
AFAICT those can't observe OOO of CPUs, just nondeterminism from interleavings different threads. I.e. they will give you sequential consistency unless you have other, worse races.
Re:The x86 architecture is the weirdo, part 2 by zozbot234 on Friday April 22, 2022 @11:53AM (#31123213)
Sequential consistency is absolutely optional, there are several other possible memory orderings that are far weaker. When programs involve multiple atomic locations concurrently, atomicity is only preserved at each separate location.