How to debug exc_bad_access in xcode 4.2

From: http://www.fengqijun.com/posts/open-nszombieenabled-help-diagnose-exc-bad-access

Enable nszombieenabled to debug exc_bad_access

In IOSProgramWhether you are a newbie or a cool man, you may encounter exc_bad_access. At this time, no information is displayed in your debug area to help you identify the problem. In this case, you need to enable nszombieenabled to provide more useful information.

In xcode 4.2, there are two methods to open nszombie.

Method 1: Add environment variables. In the menu, choose product> edit schema and run (app name). In environment variables under arguments, add nszombieenabled, the value is yes.

Method 2: Open diagnostics, select product> edit schema from the menu, select Run (app name), and enable zombie objects under memory management under diagnostics.

At this point, when running the program, it will show which instance has been release, and you will send a message to this object.