LayerMask sets Raycast.hit to 0

Any idea why when I add a layer mask it is setting my RaycastHit to 0? It's basically going through everything despite the layermask being set to only one layer.

Any help is greatly appreciated. Thank you.

 #pragma strict
 
 private var hitInfo : RaycastHit;
 
 private var tr : Transform;
 
 var mask : LayerMask = -1;
 
 
 
 function Awake () {
     tr = transform;
     
 
 
 }
 function Update () {
 
     // Cast a ray to find out the end point of the laser
 
     hitInfo = RaycastHit();
     
     Physics.Raycast (tr.position, tr.forward, hitInfo, mask.value);
     
     Debug.Log(hitInfo.distance);
     
 
 
 }
 
 function GetHitInfo () : RaycastHit {
     return hitInfo;
     
 }