anchor.diff:              ! Deallocate hash table and set scalar attributes to 0.
   
               ! In/Out:
  -            !    ht: hash table.  On output all array attributes are deallocated
  +            !    ht: hash table.  On output all array attributes are deallocated/
               !        and all scalar attributes are set to 0.
   
               use checking, only: check_deallocate
  
positive.code: 
  !--- Allocation/deallocation ---
  
          subroutine alloc_hash_table(nslots, nentries, data_len, payload_len, max_free_reqd, seed, ht)
  
              ! Allocate hash table and initialise storage.
  
              ! In:
              !    nslots, nentries, data_len, payload_len, max_free_reqd, seed: see
              !        descriptions in hash_table_t.
              ! Out:
              !    ht: hash table.  On output all array attributes are allocated
              !        and all scalar attributes are set to their corresponding
  
negative.code:             use checking, only: check_allocate
  
              integer, intent(in) :: nslots, nentries, data_len, payload_len, max_free_reqd, seed
              integer, intent(in), optional, target :: data_label(:,:), payload(:,:)
              type(hash_table_t), intent(out) :: ht
  
              integer :: ierr
  