anchor.diff:  #endif
   
   #ifdef useExtSolver
  -  call Ext_solver(MPI_COMM_WORLD, hypre_A, hypre_grid, num_procs, &
  +  call Ext_solver(MPI_COMM_WORLD, hypre_A, hypre_grid, myid, num_procs, &
       ilower, iupper, etastar, &
       etanew, nx, ny, dt, maxits, eps, ierr)
   #endif
  
positive.code: 
  ! ---------------------------------------------------------------------------
  
  subroutine Ext_solver(MPI_COMM_WORLD, hypre_A, hypre_grid, num_procs, &
      ilower, iupper, etastar, &
      etanew, nx, ny, dt, maxits, eps, ierr)
    implicit none
  
negative.code:   integer,          intent(in)  :: MPI_COMM_WORLD
    integer*8,        intent(in)  :: hypre_A
    integer*8,        intent(in)  :: hypre_grid
    integer,          intent(in)  :: myid
    integer,          intent(in)  :: num_procs
    integer,          intent(in)  :: ilower(0:num_procs-1,2)
    integer,          intent(in)  :: iupper(0:num_procs-1,2)
  