Programmatic UISearchDisplayController retain issue

gistfile1.m

#import <UIKit/UIKit.h>

@interface ExampleViewController : UIViewController
@end

#pragma mark -

@implementation ExampleViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    UISearchBar *searchBar = [UISearchBar new];

    // from the discussion section of -[UIViewController searchDisplayController]:
    //
    //   > This property reflects the value of the searchDisplayController outlet
    //   > that you set in Interface Builder. If you create your search display
    //   > controller programmatically, **this property is set automatically by
    //   > the search display controller when it is initialized.**
    //
    // (emphasis mine)
    id sdc = [[UISearchDisplayController alloc] initWithSearchBar:searchBar contentsController:self];

    // passes
    NSAssert(sdc == self.searchDisplayController,
             @"Creating a search display controller programmatically should automatically set self.searchDisplayController");
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear:animated];

    // fails
    NSAssert(self.searchDisplayController != nil,
             @"Should still have the search display controller initialized in -viewDidLoad");
}

@end

// Console
// 2012-11-26 16:57:04.356 ExampleApp[37806:c07] *** Assertion failure in -[ExampleViewController viewDidAppear:], /Users/andrew/ExampleApp/Source/ExampleViewController:
// 2012-11-26 16:57:04.358 ExampleApp[37806:c07] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Should still have the search display controller initialized in -viewDidLoad'