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POChanges to reference counting in iOS 7?
 

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  1. POChanges to reference counting in iOS 7?
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    <p>I'm currently working on fixing some iOS 7 display issues on a legacy app which was not built with ARC, and have run into some inconsistent behaviour with the <code>dealloc</code> method between iOS versions 6 &amp; 7. I can't find any other mention of these changes in any documentation or community discussions, so I wonder if anyone here could shed some light on what's happening here?</p> <p>My previous code, (which works in iOS6, looks like this):</p> <pre><code>@interface MyViewController() @property (retain) AdHandler *adHandler; @end @implementation MyViewController @synthesize adHandler = _adHandler; - (id) initWithAdHandler:(AdHandler*)anAdHandler { self = [super init]; _adHandler = [anAdHandler retain]; return self; } - (void)dealloc { [super dealloc]; [_adHandler release]; _adHandler = nil; } ... @end </code></pre> <p>When stepping through the code in iOS 6, I've found that after the <code>dealloc</code> statement, <code>[_adHandler retainCount]</code> is still positive, and the object is still available.</p> <p>In iOS 7 however, after the <code>dealloc</code> statement, <code>retainCount</code> has somehow hit zero, and the <code>_adHandler</code> object has been <code>dealloc</code>'d, and therefore my call to <code>release</code> causes an <code>EXC_BAD_ACCESS</code>.</p> <p>I can fix this simply by moving my <code>[adHandler release]</code> call to before the <code>dealloc</code> call, but my question is why is this happening? Why is <code>dealloc</code> releasing objects that it has no responsibility for? Is there any documentation anywhere on why dealloc behaviour has changed in this way?</p>
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    1. USmajackson
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    1. CO[**Never** use `retainCount`.](http://whentouseretaincount.com)
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      1. POChanges to reference counting in iOS 7?
      1. USDavid Rönnqvist
    2. COWhen you implement `-dealloc` in a non-ARC app, `[super dealloc]` should be the last statement, not the first.
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      1. POChanges to reference counting in iOS 7?
      1. USbneely
    3. COIf you use instruments, you can find out exactly where retain/release/autoreleases are happening on your objects
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      1. POChanges to reference counting in iOS 7?
      1. USMike Pollard
 

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