Hi, I observe a deadlock from time to time using the msvc + microsoft std library and recently asked a question about std::shared_mutex in their dev forum: https://developercommunity.visualstudio.com/t/std::shared_mutex-deadlock/10299619#T-ND10299805 Now I would like to know if the gnu std library exhibits the same behaviour. (I just could not test the code on Linux yet.) In short: Thread C tries(!) to write access (lock via scoped_lock or unique_lock) while Thread B already has(!) it shared locked - read access (via std::shared_lock). Meanwhile Thread A is also trying(!) to read access (via std::shared_lock) the shared_mutex. In order: Thread B: std::shared_lock _(mutex); // ok - acquired and now waiting for Thread A to finish Thread C: std::scoped_lock _(mutex); // ok - stuck for now Thread A: std::shared_lock _(mutex); // failure - stuck as well -> Thread C should be stuck but Thread A should be able to acquire the shared lock and continue but it is stuck as well. Thank you.
