gistfile1.txt

@class Foo;
@interface Foo2 : NSObject
- (void) boo:(Foo*)foo;
@property (nonatomic, strong) Foo* foo;
@end

@interface Foo : NSObject
@property (nonatomic, strong) Foo2* foo2;
- (instancetype) initWithFoo2:(Foo2*)foo2;
- (void) boo:(void(^)())block foo2:(Foo2*)foo2;
@end

@implementation Foo

- (instancetype) initWithFoo2:(Foo2*)foo2
{
    if (self = [super init]) {
        self.foo2 = foo2;
    }
    return self;
}

- (void) boo
{
    [self.foo2 boo:self];
}

- (void) releaseFoo2
{
    self.foo2 = nil;
}

@end

@implementation Foo2

- (void) boo:(Foo*)foo
{
    self.foo = foo;
    __weak Foo2* wself = self;
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

        
      //  [wself boo];
        
        NSLog(@"%@", wself);
        [wself.foo releaseFoo2];
        NSLog(@"%@", wself);
        
    });
}

- (void) boo
{
    NSLog(@"%@", self);
    [self.foo releaseFoo2];
    NSLog(@"%@", self);
}

@end

@interface AppDelegate ()

@end

@implementation AppDelegate


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    Foo2* foo2 = [[Foo2 alloc] init];
    Foo* foo = [[Foo alloc] initWithFoo2:foo2];
    [foo boo];
    // Override point for customization after application launch.
    return YES;
}