[libcxx-commits] [libcxx] [libc++] std::condition_variable_any overloads accepting std::stop_token don't register for stop callbacks (PR #77099)

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@@ -257,23 +258,38 @@ condition_variable_any::wait_for(_Lock& __lock, const chrono::duration<_Rep, _Pe
 
 template <class _Lock, class _Predicate>
 bool condition_variable_any::wait(_Lock& __lock, stop_token __stoken, _Predicate __pred) {
-  while (!__stoken.stop_requested()) {
+  shared_ptr<mutex> __mut = __mut_;
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huixie90 wrote:

I am not sure what we really want to take the copy of ownership of the mutex in these overloads. By taking the copy, it sometimes works and sometimes it does not . (If notified by the request_stop followed by the destructor call, it is UB on accessing the internal cv)

if we were allowed to break the ABI, we would bundle the cv and mutex  into the shared_ptr. but we are not.  I am not sure if we just not taking the copy at all and claim we don’t support destroy-while-waiting, rather than here sometimes it works and sometimes it doesn’t. 

https://github.com/llvm/llvm-project/pull/77099