: If *this
does not have ownership of a stop state, returns false.
Otherwise, atomically determines whether the owned stop state
has received a stop request,
and if not, makes a stop request.
The determination and making of the stop request are an
atomic read-modify-write operation ([intro.races]
If the request was made,
the callbacks registered by associated stop_callback
are synchronously called.
If an invocation of a callback exits via an exception
is called ([except.terminate]
A stop request includes notifying all condition variables
of type condition_variable_any
temporarily registered during
an interruptible wait ([thread.condvarany.intwait]
— end note