Volatile + relaxed atomic load/store

[rikyborg]

@alice

A special hardware memory location that's only ever accessed in a volatile manner is, in my book, quite different from a memory location that also has non-volatile accesses. (And creating a reference to it is essentially that.)

Yes, I understand and in general I agree. My point is that even if I structure my code like you suggested in the other thread thus avoiding ever creating a reference (which I'll try to do at some point!), the question of this thread still applies: how to get atomic semantics on top of volatile semantics?

@alice

The thing you're worried about is how the compiler will optimize code containing your writes. Inline assembly is as close to unoptimizable as you can get.

OK, makes sense. I'll try that, thanks!

Sorry for pressing, let me ask this again to make sure I understood you correctly:

@rikyborg

Do you mean one possible way is to use volatile-only operations (not atomic), put an unsafe impl Sync for VolatileCell {}, and assume this is not UB because I'm not using ordinary memory?