On Jan 15, 2014, at 1:56 AM, Kyle Sluder wrote: > On Jan 14, 2014, at 9:05 PM, Quincey Morris > <quinceymor...@rivergatesoftware.com> wrote: >> >> Second, I’ve noticed some very surprising behavior with weak references at >> dealloc time. If an object being deallocated has a weak reference to another >> object, and it was the only reference so that the other object is also due >> to be deallocated […]
That doesn't make sense. A weak reference can't be the only reference to an object. As I'm sure you know, objects are deallocated (and weak references nil'd) when the last *strong* reference is broken. Whatever the mysterious behavior is, I don't think it can be that. I suppose it could be that the object has a weak reference to itself and that could cause some sort of problem if a message were sent through that weak reference during -dealloc. I would expect that having a weak reference to self would be fairly common and that ARC would have to cope properly. Since the original crash was an access violation inside the runtime, I would suspect a memory smashing bug prior to the destruction of the OUIInspectorPane subclass instance. When ARC goes to unregister that instance's weak reference, it steps on a land mine that was laid previously. Since the crash seems not to happen at random, I guess the memory smashing was done shortly before this. (It's certainly possible for a corrupted data structure to not influence anything until a long time after the corruption has happened, but in that situation the crash is more likely to affect random other code.) So, I'd suspect the -dealloc of the OUIInspectorPane subclass, prior to the implicit call of super's -dealloc. Or the code which does the final release of that object which provokes the deallocation. Regards, Ken _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
