I have specified the Subroutine. But the compiler remaind me that the Subroutine is Undefined.
subroutine check_indomain_particles
!$acc routine seq ......
subroutine step
!$acc routine seq
!include 'common.2D'
use common2D
interface
subroutine ac
!$acc routine seq
use common2D
end subroutine ac
subroutine check_limits_2D
!$acc routine seq
use common2D
end subroutine check_limits_2D
subroutine check_indomain_particles
!$acc routine seq
use common2D
end subroutine check_indomain_particles.......
Error: nvlink error : Undefined reference to ‘check_indomain_particles_’ in ‘obj\Release\sourcefile\step_symplectic_2D.o’