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[BrianMu]

I got a crash log from my user. The "top" part of the log looks like this:

Exception Type: EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x00000000
Crashed Thread: 0

Thread 0 Crashed:
0 libobjc.A.dylib 0x000026f6 objc_msgSend + 18
1 UIKit 0x0011928c -[UISegmentedControl dealloc] + 12
2 CoreFoundation 0x00038f30 -[NSObject release] + 24
3 UIKit 0x00095c4c -[UIBarButtonItem dealloc] + 64
4 CoreFoundation 0x00038f30 -[NSObject release] + 24
5 UIKit 0x0008ec7a -[UINavigationItem dealloc] + 86
6 CoreFoundation 0x00038f30 -[NSObject release] + 24
7 UIKit 0x0009596c -[UIViewController dealloc] + 484
8 myApp 0x000041f6 -[myAppListViewController dealloc]

If I am reading this correctly, it has crashed trying to send a dealloc message to a segmented control (presumably the one I have on my navigation bar).

The relevant part of the segment control creation is:

NSString *strT = [self.dateformatUse stringFromDate:[NSDate date]];
NSString *strToday = [[[NSString alloc] initWithString:strT]autorelease];
NSArray *arSegments = [[NSArray alloc] initWithObjects:@"<",strToday,@">",nil];
UISegmentedControl *segctrlT = [[UISegmentedControl alloc] initWithItems:arSegments];
[arSegments release];
// set various segment control attributes
self.navigationItem.titleView = segctrlT;
self.segctrlTitle = segctrlT;
[segctrlT release];

in ViewDidUnload I have:

self.segctrlTitle = nil;

in dealloc for the view controller I have

[self.segctrlTitle release];

I am figuring either I shouldn't release (or rather should use autorelease) the components I use to build the segmented control in the creation part, or I shouldn't be setting it to nil in my ViewDidUnload routine. The crash is very elusive, so doing a "fix" and then testing it doesn't really work. I was hoping someone would see what I am doing wrong.