run error sends me to code I didn't write

Question

Whenever I click a certain button, the app always dies and I'm sent to:

int main(int argc, char *argv[])
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    THIS LINE ==> int retVal = UIApplicationMain(argc, argv, nil, nil);
    [pool release];
    return retVal;
}

For those who are familiar, you know that I didn't write this code. I don't know how to find out where my error is!

Also, the output shows this:

2011-10-27 21:03:17.690 My Program[55441:207] Unbalanced calls to begin/end appearance transitions for <UITabBarController: 0x68181f0>.
(lldb) 

I don't know where to look short of commenting out code line by line until I find the issue. Any suggestions?

Answer 1

on the button click a new UIView is pushed into the Window. That view's .xib had linkage that was bad (linked to an IBOutlet that didn't exist in code anymore because it was renamed).

I set up the correct linkage in Interface Builder and I no longer got the error. I wish xcode would at least tell you there's a problem with one of your .xib files.

PART 2

Shortly after that fix I was getting this error again. After searching the web for a bit, I found that it could be related to a memory leak so I ran the Project->Analyze tool. When I fixed Xcode's suggestions, everything ran fine.

Answer 2

You are likely running the fact that Xcode 4.2 does not show stack traces most of the time. Check this SO post.

Xcode 4.2 debug doesn't symbolicate stack call