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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/31/25 10:31, Alice Ryhl wrote: > I do agree that this behavior has a lot of potential to surprise > users, but I don't think it's incorrect per se. It was done > intentionally for Condvar, and it's not unsound. Just surprising. Yes, I agree that it is not unsound.` For conditional variables, wait() is clearly going to release the mutex to wait for someone else so the surprise factor is much less. Having it return a new guard would be closer to std::sync::Condvar::wait, but it'd add churn and I'm not sure how much you all care about consistency with std. std has the extra constraint of poisoned locks so it doesn't really have a choice. Paolo > Of course, that doesn't mean we can't change it. Condvar could be > updated to use ownership in that way, and doing say may be a good > idea.