anchor.diff:              j = i - 1
               tmp = rank(i)
               do while ( j >= 1 )
  -                if (arr(rank(j)) - arr(tmp) < tol) exit
  +                if (arr(rank(j)) - arr(tmp) < 0) exit
                   rank(j+1) = rank(j)
                   j = j - 1
               end do
  
positive.code:     ! [reply] - FM: I'm actually not sure I need this anymore, the dependency
      ! [reply] - FM: was removed a while ago. It might come in use in the future.
      ! [reply] - FM: What do you think?
      pure subroutine insertion_rank_int(arr, rank, tolerance)
  
          ! Rank an int array in increasing order using the insertion sort
          ! algorithm.
  
negative.code:         !    NOTE: rank must have at least the dimensions of arr on input.
  
          integer, intent(in) :: arr(:)
          integer, intent(inout) :: rank(:) ! inout to avoid automatic deallocation
                                            ! of an allocatable array on entry
  
          integer :: i, j, tmp
          real(p) :: tol
  
          forall (i=1:size(arr)) rank(i) = i
  
  