Crashing when deleting value with no child in Binary Tree

In my binary tree, I can delete values that have other values extending from it. If they don't, or if it is the only value, the program crashes. Not sure how to fix it. This is the deletion part of the code:

void delete_tree (binarytree *t, int x)
{
   binarytree temp;

   if (!is_empty(*t))
   {
       if (x == (*t)-> data)
       {
           if (((*t) -> left == NULL)&&((*t) -> right == NULL))
           {
               temp = (*t);
               (*t) = NULL;
               free (temp);
           }

           if (((*t) -> left != NULL)&&((*t)-> right == NULL))
           {
                temp = (*t);
                (*t) = (*t) -> left;
                free (temp);
           }
           if (((*t)-> left == NULL)&&((*t)-> right != NULL))
           {
               temp = (*t);
               (*t) = (*t) -> right;
               free (temp);
           }
           if (((*t) -> left != NULL)&&((*t) -> right != NULL))
           {
               temp = (*t)-> right;
                   while (temp -> left != NULL)
                       {
                           temp = (*t) -> left;
                       }

               temp -> left = (*t) ->left;
               temp = (*t);
               (*t) = (*t) -> right;
               free (temp);

           }

       }
       else {
            if ( x <= (*t) -> data)
                delete_tree(&(*t) -> left, x);

            else
                delete_tree(&(*t) -> right, x);
        }


   }
   else printf("No data found.\n");
}

Select allOpen in new window

I'm a noobie at programming so any help would be appreciated. :)