objective-c – iOS,Objective c在一开始就抛出异常

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    // Override point for customization after application launch.
    self.viewController = [[[ViewController alloc] initWithNibName:@"ViewController" bundle:nil] autorelease];
    self.window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];  throw exception on this line
    return YES;
}

例外情况如下：

Thread 1: Program received signal: "SIGABRT"

当main.m上显示实际异常时(我没有创建它也看不到它)：

int main(int argc,char *argv[])
{
    @autoreleasepool {
        return UIApplicationMain(argc,argv,nil,NSStringFromClass([AppDelegate class]));
    }
}

谢谢！