title: I get Thread 1: signal SIGABRT and my IOS App crashes
body: <p>I am working on an IOS App on Swift and its connected to Firebase.  Once I reach a specific page in the run mode, my app crashes and I get this error message without any details.  Please help</p>
  
  <p>I do not have any errors with my Outlets and I have tried debugging with break points but it still takes my to the AppDelegate with this error without details.  I am clueless.  Before it used to work the code should be fine and data were being inputted to the DB but something happened since I have created the login page.</p>
  
  <pre><code>//  LoginViewController.swift
  //  Together
  
  
  import UIKit
  import Firebase
  
  
  class LoginViewController: UIViewController {
  
      @IBOutlet weak var usernameTxt: UITextField!        
      @IBOutlet weak var passTxt: UITextField!        
      @IBAction func userLoginBtn(_ sender: Any) {
  
          var pass = passTxt.text
  
          Auth.auth().signIn(withEmail: usernameTxt.text!, password: passTxt.text!){
              (user, error) in
              if error == nil{
                  self.performSegue(withIdentifier: "loginToHome", sender: self)}
              else{
                  let alertController = UIAlertController(title: "Error", message: error?.localizedDescription, preferredStyle: .alert)
  
                  let defaultAction = UIAlertAction(title: "Ok", style: .cancel, handler: nil)
  
                  alertController.addAction(defaultAction)
                  self.present(alertController, animated: true, completion: nil)
  
              }            
          }            
      }
  
      override func viewDidLoad() {
          super.viewDidLoad()
  
  
      }
  
  }
  </code></pre>