Script makes my unity Crash

I am new to unity and don't know if this script is good, it's bits and bobs of other scripts it give me no errors though but every time I press play my unity crashes. I am hoping someone could tell me why that is or hint to a reason why it might be and btw I know this code is terrble but I am just a beginner.

 using UnityEngine;
 using System.Collections;
 
 public class terrainGenerator : MonoBehaviour {
 
     //Raycast
     bool foundhit = false;
     RaycastHit hit = new RaycastHit();
     public Transform cube;
     public float raycastDist = 10;
     public string tagCheck = "Edge";
     public bool checkAllTags = false;
 
     //block placement
     public bool running = false;
     public float speed = 4;
     Ray ray;
     
     
     //spawning
     public GameObject[] obj;
     public float spawnMin = 1;
     public float spawnMax = 2;
     
     // Use this for initialization
     void Awake ()
     {
         spawn();
         running = true;
         while (running == true)
            
 
            if(Physics.Raycast(transform.position, transform.forward, raycastDist))
            {
                foundhit = true;
            }
            if(foundhit == true)
            {
                if(Physics.Raycast(transform.position, transform.forward, raycastDist))
                {
                    
                }
            }
        }
 
 
     void spawn()
     {
         Instantiate(obj[Random.Range(0, obj.GetLength(0))], transform.position, Quaternion.identity);
         Invoke("spawn", Random.Range(spawnMin, spawnMax));
     } 
 }