Crash issue for [NSString stringWithFormat:]

Question

I submitted my application to apple for review.Apple rejected and gave me the following crash report.

Thread 0 Crashed:
1   Foundation                      0x3595dd04 _NSDescriptionWithLocaleFunc + 44
2   CoreFoundation                  0x36ae696e __CFStringAppendFormatCore + 7998
3   CoreFoundation                  0x36a611d8 _CFStringCreateWithFormatAndArgumentsAux + 68
4   Foundation                      0x3595dc2e +[NSString stringWithFormat:] + 54
5   WIPTime                         0x0001572e -[NSDate(TKCategory) reportHeader] + 66
6   WIPTime                         0x0006bd9e -[ReportDelegate tableView:cellForRowAtIndexPath:] + 474
7   UIKit                           0x36de009c -[UITableView(UITableViewInternal) _createPreparedCellForGlobalRow:withIndexPath:] + 540
8   UIKit                           0x36ddf17a -[UITableView(_UITableViewPrivate) _updateVisibleCellsNow:] + 1070
9   UIKit                           0x36dde904 -[UITableView layoutSubviews] + 200
10  UIKit                           0x36d830d8 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 176
11  CoreFoundation                  0x36a651f4 -[NSObject performSelector:withObject:] + 36
12  QuartzCore                      0x36241a9e -[CALayer layoutSublayers] + 210
13  QuartzCore                      0x362416b6 CA::Layer::layout_if_needed(CA::Transaction*) + 210
14  QuartzCore                      0x3624583c CA::Context::commit_transaction(CA::Transaction*) + 220
15  QuartzCore                      0x36245578 CA::Transaction::commit() + 308
16  QuartzCore                      0x3623d4b2 CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 50
17  CoreFoundation                  0x36adab14 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 12
18  CoreFoundation                  0x36ad8d50 __CFRunLoopDoObservers + 252
19  CoreFoundation                  0x36ad90aa __CFRunLoopRun + 754
20  CoreFoundation                  0x36a5c49e CFRunLoopRunSpecific + 294
21  CoreFoundation                  0x36a5c366 CFRunLoopRunInMode + 98
22  GraphicsServices                0x30b3e432 GSEventRunModal + 130
23  UIKit                           0x36dade76 UIApplicationMain + 1074
24  WIPTime                         0x00003032 main + 42
25  WIPTime                         0x00002ffc start + 32

the implementation for the reportHeader is following :

  -(NSString *) reportHeader
    {
    NSString *realWorld=[self dateDescriptionRealWorld];
    NSString *year=[self yearString];
    NSString *weekDay=[self weekdayString];
    NSString *returnString=[NSString stringWithFormat:@"%@ %@ %@",weekDay,realWorld,year];

    return returnString;
    }

Utility methods that are used within the method is following:

-(NSString *) dateDescriptionRealWorld
{

    return [NSString stringWithFormat:@"%@ %@",[self dayString],[self monthStringWithCod]];
}

- (NSString*) monthString{
    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];  
    [dateFormatter setDateFormat:@"MMMM"];
    return [dateFormatter stringFromDate:self];
}

- (NSString*) yearString{
    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];  
    [dateFormatter setDateFormat:@"yyyy"];
    return [dateFormatter stringFromDate:self];
}

- (NSString*) dayString{
    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];  
    [dateFormatter setDateFormat:@"dd"];
    return [dateFormatter stringFromDate:self];
}

- (int) weekday{

    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *comps = [gregorian components:(NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit | NSWeekdayCalendarUnit) fromDate:self];
    int weekday = [comps weekday];
    [gregorian release];
    return weekday;
}

-(NSString *) weekdayString
{
    NSDate *date=self;
    int weekday=[date weekday];
    if (weekday ==0) {
        return @"Sat";
    }
    else if(weekday ==1)
    {
        return @"Sun";
    }
    else if(weekday ==2)
    {
        return @"Mon";

    }
    else if(weekday ==3)
    {
        return @"Tue";

    }
    else if(weekday ==4)
    {
        return @"Wed";

    }
    else if(weekday ==5)
    {
        return @"Thu";

    }
    else if(weekday ==5)
    {
        return @"Fri";

    }

}

Answer 1

Where does the variable realWorld come into the picture? I suspect it's an class field that you assign the result of calling dateDescriptionRealWorld, but never retain. That's just a guess, though, based on incomplete information.

Answer 2

A few thoughts... You should use switch/case and a default case instead of if/else. Also, you are naming your methods incorrectly. Instead of a weekday method, you should name it after what it does and returns, like, weekdayFormatted. In addition, you should probably not be alloc'ing a new dateFormatter in every method but use one NSDateFormatter in your class, and set its format in each of these methods.

I suggest removing all your methods and put the formatting inside your reportHeader method, to clean it up. You are alloc'ing quite a bit and although you use autorelease, you are relying on it too much to clean up otherwise perhaps unwise memory management.

That may not be too "practical" quick fix for you but those are the things that I see which could lead to better memory management.

Also - @Aadihira has a great question and you should show the monthStringWithCod method as well.