mp_sum_b Subroutine

   SUBROUTINE mp_sum_b(msg, gid)
      !! Logical OR reduction
      !!
      !! MPI mapping
      !! mpi_allreduce

      LOGICAL, INTENT(INOUT)                             :: msg
         !! Datum to perform inclusive disjunction (input) and resultant inclusive disjunction (output)
      TYPE(mp_comm_type), INTENT(IN)                                :: gid
         !! Message passing environment identifier

      CHARACTER(LEN=*), PARAMETER :: routineN = 'mp_sum_b'

      INTEGER                                            :: handle, ierr, msglen

      CALL timeset(routineN, handle)
      ierr = 0
      msglen = 1
#if defined(__parallel)
      CALL mpi_allreduce(MPI_IN_PLACE, msg, msglen, MPI_LOGICAL, MPI_LOR, gid%handle, ierr)
      IF (ierr /= 0) CALL mp_stop(ierr, "mpi_allreduce @ "//routineN)
#else
      MARK_USED(msg)
      MARK_USED(gid)
#endif
      CALL timestop(handle)
   END SUBROUTINE mp_sum_b