iphone ios XCode4如何偵錯工具忽然崩潰而找不到掛的代碼

XCode4設定不太一樣: 在Edit–>Scheme裡面 找到Arguments(在xcode 4.2中，在菜單 product->edit scheme中）

把下面3個值設定成YES

NSAutoreleaseFreedObjectCheckEnabled

NSZombieEnabled

NSDebugEnabled

另外轉載2篇調試EXC_BAD_ACCESS的好文http://blog.zol.com.cn/2387/article_2386505.html
http://www.cnblogs.com/likwo/archive/2011/02/28/1967066.html

老外也有這麼說的：I had similar issue; turns out I was
not retaining a UIButton properly. How I found the cause: - Enable zombies - Run the project with 'Allocations' instrument - Use the app to trigger the bug - Check that Instruments show message 'Zombie Messaged' on the timeline - There should be a link that
opens CALayer details: when it was allocated and deallocated - You are interested in the place where is was allocated, should be that aha!!! place in your code


我是用模擬器上 使用zombies，然後運行程式，崩潰的時候會有提示崩潰點，同時有代碼。
轉另一個人文章：

 方法一：

PAEHoldTranMainControl *control = [[PAEHoldTranMainControl alloc]init];

            [self.navigationController pushViewController:control animated:YES];

            [control release];

alloc了一個control,release,運行就崩潰了。而且沒有任何提示，console裡只顯示exc_bad_access

利用NSZombieEnabled參數，MallocStackLogging參數，顯示 -[CALayer release]: message sent to deallocated instance 0x13570810

折騰了半天，最後用如下方法定位問題：

開啟instrument-->ios simulator：

選擇all－－》 zombies運行，斷開時，查看stack trace，即可跟蹤

 

 方法二：例如console裡的輸出如下：

TestAPP[1472:207] *** -[NSObject release]: message sent to deallocated instance 0x6019170

在 gdb console 裡面， 運行 shell malloc_history <pid> <mem_address>

pid = process ID (e.g. 1472)

mem_address = memory address of instance (e.g. 0x6019170) 

即會出現調用棧