NSZombie Enabled, MallocStackLogging - iphone

Question

I am testing an EXE_BAD_ACCESS error. I have set NSZombieEnabled, MallocStackLogging, MallocStackLoggingNoCompact to YES. now in the debugger I get this message when I run my app in the debug mode from the device I could see this:
iota(3586) malloc: recording malloc stacks to disk using standard recorder
iota(3586) malloc: stack logs being written into /private/var/mobile/Applications/8E21A85B-369E-4487-962B-1550E56602DC/tmp/stack-logs.3586.iota.index
iota(3586) malloc: Please issue: cp /private/var/mobile/Applications/8E21A85B-369E-4487-962B-1550E56602DC/tmp/stack-logs.3586.iota.suRQjy.link /tmp/
and when I am about to hit the error I get,
2011-02-14 14:29:44.350 iota[3586:307] *** -[CFString autorelease]: message sent to deallocated instance 0x81eab70
Finally when I give the command in debugger to see the stack trace
(gdb) shell malloc_history 3586 0x81eab70
I get
malloc_history cannot examine process 3586 because the process does not exist.
Can anyone tell me what I am doing wrong, before the error is about the occur , I set
set env MallocStackLogging 1 in the debugger too
Thanks in Advance

Answer 1

You might not be able to look at the malloc_history because you're running this on the device. I had the same error and Instruments was also freezing or not starting my application.
But - if I ran in the iOS simulator and then configured the allocations tool to handle zombies (this option wasn't available on the device) then I can see pretty quickly the object which was prematurely released.

Answer 2

From what I understand you are releasing manually a string that is already on the autorelease Pool.
All strings created with
[NSString stringWithFormat:#"some %#", #"text"];
And
[NSString stringWithString:#"some text"];
must not be manually released.