Re: [Boost-users] [Statechart] Why does this state machine enter unstable state only in debug mode?

Finally I found the cause: This issue is caused by the "Windows procedure can be reentrant" but the process_event can't. When I call MciWndPlay in the windows procedure another msg is generated by this call and windows try to process this new message in the same Windows procedure call, this cause the fsm entered a unstable state.

Right, process_event is not reentrant. In a scenario where you'd wish it was, asynchronous_state_machine is most likely the better choice than state_machine. Regards, -- Andreas Huber When replying by private email, please remove the words spam and trap from the address shown in the header.