Why is ARC complaining about dispatch_queue_create and dispatch_release in iOS 6?
automatic-ref-counting, grand-central-dispatch, ios, memory-management
Solution
In iOS 6 you can cmd+click dispatch_queue_t and see this:
/*
* By default, dispatch objects are declared as Objective-C types when building
* with an Objective-C compiler. This allows them to participate in ARC, in RR
* management by the Blocks runtime and in leaks checking by the static
* analyzer, and enables them to be added to Cocoa collections.
* See <os/object.h> for details.
*/
So simply use strong in the property (unless the queue is referenced elsewhere and you really want a weak reference).
Before iOS 6 you have to do memory management yourself using dispatch_retain and dispatch_release. Doing this in iOS 6 will throw a compiler error.
Problem
I declared a property to reference a GCD queue: ``` @property (assign) dispatch_queue_t backgroundQueue; ``` In the init method of a class I create a serial queue: ``` backgroundQueue = dispatch_queue_create("com.company.app", DISPATCH_QUEUE_SERIAL); ``` ARC complains: "Assigning retained object to unsafe_unretained variable; object will be released after assignment" Must I use __bridge_transfer? In -dealloc I am releasing the queue: ``` dispatch_release(backgroundQueue); ``` Again, ARC complains: "ARC forbids explicit message send of 'release'" I find this confusing because this is a C function call and thought queues are C objects for which I must take care of memory management myself! Since when does ARC handle the C-objects for me?