[Feature Request] strong variant of box-cas!

[sorawee]

box-cas! is weak in a sense that there could be a spurious failure. It would be nice to have a strong variant that guarantees no failure in the standard library.

[samth]

I'm not sure this is a good idea. Most algorithms that use CAS are going to want to have some non-trivial backoff strategy, rather than just busy-looping.

[sorawee]

I will let other people who know about concurrency algorithm more than I do weigh in on this (@Bogdanp?), but it seems standard for languages to provide this function (e.g. C++, Rust). I myself simply try to fix bugs that occur due to unexpected spurious failure (see, e.g., emina/rosette#199) and think it would be nice if I don't have to manually loop by myself.

[samth]

Ah, I didn't realize you only wanted to avoid spurious failure. That seems reasonable to provide.