Why is my unwind segue crashing my app?
<p>I am trying to create an unwind segue that takes me back two viewControllers, and I thought I had everything set up correctly, but it crashes with no error printed when I perform the segue...</p>

<p>Here's what I've done:</p>

<p>In the DESTINATION viewController, we'll call it VC1 (bottom of the stack) I created this action:</p>

<pre><code>@IBAction func unwind(segue:UIStoryboardSegue){}
</code></pre>

<p>In the interface builder I hooked up VC3 (the third view controller up) to the unwind segue via the exit button and named it "unwind".</p>

<p>I call perform for segue like so:</p>

<pre><code>performSegue(withIdentifier: "unwind", sender: self)
</code></pre>

<p>Here is the view controllers and segue identifier</p>

<p><a href="https://imgur.com/a/gJPYQ" rel="nofollow noreferrer">http://imgur.com/a/gJPYQ</a></p>

<p>The "Delete Trip" button calls the segue AFTER all the other logic has been taken care of.</p>

<p>As soon as that is called, my app crashes with no error message and shows me the AppDelegate screen. What's going on?</p>