1! { dg-do compile } 2! { dg-options "-O1" } 3SUBROUTINE check_for_overlap (cell_length) 4 REAL, DIMENSION(1:3), INTENT(IN), OPTIONAL :: cell_length 5 REAL, DIMENSION(1:3) :: abc, box_length 6 7 IF (PRESENT(cell_length)) THEN 8 box_length(1:3)=abc(1:3) 9 ENDIF 10END SUBROUTINE check_for_overlap 11