在pushViewController中再present一个UINavigationController, dismiss之后会报内存泄露。

[smoothdvd]

[self.closestViewController.navigationController pushViewController:detailVC animated:YES];

then in detailVC:

SigninViewController *signinVC = [[SigninViewController alloc] init];
signinVC.delegate = self;
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:signinVC];
[self presentViewController:nav animated:YES completion:nil];

If I call dismiss in signInVC:

[self dismissViewControllerAnimated:YES completion:nil];

modal viewcontroller closed and will report memory leak:

[Zepo]

那就是你的 SigninViewController 没释放，在这个场景下本应该释放的吧