Crash on Sierra?

[MrNoodle]

Crash on Sierra?

[MrNoodle]

Looking at it more closely, I'm guessing what used to be a deadlock is now detected and an exception is thrown instead. Seems that -cleanupMulti, which does a dispatch_sync() is being called indirectly via -setState: from various dispatch_async() blocks.

[MrNoodle]

So, with my limited knowledge of the code, I'm thinking that the dispatch_sync() call in -cleanupMulti can be removed. Everywhere that I can tell that it's called, it's being called on the queue (either via dispatch_async() or via a dispatch_source cancel handler. If that seems correct to you then I can make the change (or you could do it yourself since it's pretty easy).

[andypotion]

@MrNoodle is right. Code was deadlocking before but Sierra throws out an exception. The fix was to either get rid of the dispatch_sync call or change it to dispatch_async. I've gone with the latter to be more cautious in case there were other things still in the queue. Fix has been pushed to the v4.x-beta branch