anchor.diff:           associated(intersections(1)%first, root1) .AND. &
            associated(intersections(1)%second, root2))
       call print_status(name, case_id, case_success, success)
  -    deallocate(intersections)
       num_intersections = 0
   
       ! CASE 4: Parallel lines that **do** intersect.
  
positive.code:          associated(intersections(1)%first, first) .AND. &
           associated(intersections(1)%second, second))
      call print_status(name, case_id, case_success, success)
      deallocate(intersections)
      num_intersections = 0
  
      ! CASE 3: An intersection after one subdivision.
  
negative.code:          associated(intersections(1)%first, first) .AND. &
           associated(intersections(1)%second, second))
      call print_status(name, case_id, case_success, success)
      num_intersections = 0
  
      ! CASE 2: Lines that **do not** intersect.
  