> It is extremely difficult for programmer-users to report bugs against the Windows API (we're supposed to direct you to Feedback Hub, but you may as well transmit your message into deep space). I've filed OS-49268777 "SRWLOCK can deadlock after an exclusive owner has released ownership and several reader threads are attempting to acquire shared ownership together" with a slightly reduced repro.
> Thanks for doing your homework and creating a self-contained repro, plus pre-emptively exonerating the STL. I've filed this OS bug as a special favor - bug reports are usually off-topic for r/cpp. The microsoft/STL GitHub repo is the proper channel for reporting STL misbehavior; it would have been acceptable here even though the root cause is in the Windows API because this situation is so rare. If you see STL misbehavior but it's clearly due to a compiler bug, reporting compiler bugs directly to VS Developer Community is the proper thing to do.