Some fortran subroutines don't use IMPLICIT NONE

[edwardhartnett]

We have code like this:

SUBROUTINE BAOPEN(LU,CFN,IRET)
  USE BACIO_MODULE
  CHARACTER CFN*(*)
  CHARACTER(80) CMSG
  integer(kind=8) IB,JB,NB,KA

  IF(LU.LT.001.OR.LU.GT.FDDIM) THEN
     IRET=6
     RETURN
  ENDIF

  IRET=BACIOL(BACIO_OPENRW,IB,JB,1,NB,KA,FD(LU),CFN,A)
END SUBROUTINE BAOPEN

Note that there is no IMPLICIT NONE, the variable CMSG is never used, and the variables LU, IRET, and A are never defined.

Also note that the INTENT for LU, CFN, and IRET can be declared but isn't.

IMPLICIT NONE is a great thing for every fortran program and subprogram. We need to use it everywhere we can.