anchor.diff:              do icycle = 1, qmc_in%ncycles
   
                   ! Zero spawning arrays.
  -                qmc_spawn%sdata = 0_int_s
  +                spawn%sdata = 0_int_s
   
                   ! Number of spawning attempts that will be made.
                   nattempts = int(nparticles)
  
positive.code: 
  contains
  
      subroutine init_simple_fciqmc(sys, qmc_in, reference, restart, ndets, dets, ref_det, psip_list)
  
          ! Initialisation for the simple fciqmc algorithm.
          ! Setup the list of determinants in the space, calculate the relevant
  
negative.code:                     if (use_sparse_hamil) then
                          associate(hstart=>hamil_csr%row_ptr(idet), hend=>hamil_csr%row_ptr(idet+1)-1)
                              do ipart = 1, abs(psip_list%walker_population(1,idet))
                                  call attempt_spawn(rng, spawn, qmc_in%tau, idet, &
                                                     psip_list%walker_population(1,idet), hamil_csr%mat(hstart:hend), &
                                                     hamil_csr%col_ind(hstart:hend))
                              end do
                          end associate
                      else
                          do ipart = 1, abs(psip_list%walker_population(1,idet))
                              call attempt_spawn(rng, spawn, qmc_in%tau, idet, psip_list%walker_population(1,idet), hamil(:,idet))
                          end do
                      end if
  
  