anchor.diff:           task(1:5) == 'START')
   
          ! Call L-BFGS-B code
  -       call setulb(dim, approximation_size, point, &
  +       call setulb(dim_c, approximation_size_c, point, &
               lower_bounds, upper_bounds, bounds_control, &
               func_value, grad_value, &
  -            f_factor, g_tolerance, &
  +            f_factor, g_tolerance_c, &
               working_real_memory, working_int_memory, &
               task, print_control, &
               char_state, bool_state, int_state, real_state)
  
positive.code:        debug_c) &
         result(error_code_c) bind(c)
  
      use, intrinsic :: iso_c_binding
      implicit none
  
      ! Signature
  
negative.code:     ! Fortran versions of arguments
      procedure(objective_function_c), pointer :: func_p
      procedure(objective_gradient_c), pointer :: grad_p
      integer :: bounds_control(dim_c)
      real(dp) :: lower_bounds(dim_c), upper_bounds(dim_c), point(dim_c)
      ! Variables and memory for L-BFGS-B
  