OSX: sound/notificaiton dispatch suddenly crashes the application

[on3iro]

Somehow something major changed in how the app is compiled on OSX. Somehow it always crashes when the onTimerEnd() callback is called for an interval.

I already had a deeper look into this. I am not quite why it happens, but the issue seems to be caused by a weird interaction of three things:

1. running the server as a daemon
2. running the server code inside a tokio runtime
3. making OS-calls (e.g. for sound playback or notification display)

None of these three things seems to cause issues on its own - they all seem to work fine, as soon as I leave one of the three out of the equation. (so no daemon -> tokio + sound works fine, no tokio -> daemon + sound works fine, no sound/notification -> no crash)

Maybe there is something inherently wrong with the way my server is structured. I will have to take a deeper look into server-side tokio code and how it handles blocking and threads.