Question

Instruments detect a memory leak:

(Leaked Object= "__NSCFString")

This is my code:

-(NSArray*)loadAllPages{
    NSManagedObjectContext *context = [self managedObjectContext];
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription
                                   entityForName:@"Page" inManagedObjectContext:context];
    [fetchRequest setEntity:entity];
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc]
                                        initWithKey:@"date" ascending:YES];
    [fetchRequest setSortDescriptors:[NSArray arrayWithObject:sortDescriptor]];
    [sortDescriptor release];

    NSError *error = nil;
    myArray = [[NSArray alloc ]initWithArray:[[context executeFetchRequest:fetchRequest error:&error]autorelease]];

    [fetchRequest release];
    if (myArray == nil)
        NSLog(@"%@",error);
    return myArray;
}

The line where leak is pointed at is initialization of myArray.
If I do not return myArray, this leak doesn’t occur, so this is strange for me.

Answer 1

In this line

myArray = [[NSArray alloc ]initWithArray:[[context executeFetchRequest:fetchRequest error:&error]autorelease]];

the square brackets are slightly wrong.
The autorelease is sent to the result of [context executeFetchRequest:...], not to the allocated array.

[context executeFetchRequest:...] returns an autoreleased array. Sending autorelease to that array is an error. And myArray is allocated, but not released in your code.

The Xcode static analyzer also reports this as an error:

I assume that you meant

myArray = [[[NSArray alloc] initWithArray:[context executeFetchRequest:fetchRequest error:&error]] autorelease];

which would result in an autoreleased array myArray.