Open Radar

 
09-Apr-2013 12:01 PM Kenny Bongort:
Summary:

We see many reports of a relatively common but hard-to-reproduce crash that comes from CLConnectionClient::sendCachedMessages(). Our automatic crash reporting system has collected 176,088 reports like the one attached since we started collecting them in October 2012.

Steps to Reproduce:

Use a CLLocationManager either to poll location or for significant location change notifications. In the latter case, this crash occurs much more frequently, but still not reliably enough to reproduce easily.

Regression:

Yes, this is a new bug since iOS 6.0. It affects every version of iOS 6.

Notes:

The crash ultimately comes from CFDictionaryCreateMutableCopy having an over-released CFDictionary argument. In cases where the pointer is a new object, we get a doesNotRecognizerSelector: exception, and the selector is "count".


09-Apr-2013 12:01 PM Kenny Bongort:
'Google-Search_2-5-1_2013-04-09_iOS-6-1_Top-Crash_07.mztlrpmu.zip_1.crash' and 'Google-Search_2-5-1_2013-04-09_iOS-6-1_Top-Crash_04.dblbycau.zip_1.crash' were successfully uploaded


17-Apr-2013 12:38 PM Apple Developer Bug Reporting Team :
Engineering has provided the following feedback regarding this issue:  

This race should only happen if you're in the habit of creating and destroying CLLocationManagers. Instead, please consider allocating only one (e.g. hang it off the app delegate instead of a view) and merely stopping it when you're done rather than destroying it.


17-Apr-2013 01:29 PM Kenny Bongort:
I am very nearly certain that we do not destroy CLLocationManagers; I even went as far as swizzling -[CLLocationManager dealloc] to stick in an assert. We do use a couple of CLLocationManager instances, and the UIWebView uses a third, but ours are managed by singletons that are never released, and the UIWebView doesn't appear to release its location manager either.