Created attachment 13081 [details]
testcase

(In reply to comment #0)
> The attached test code using a generic interface block produces wrong output
> when compiled with gfortran, and works fine with pgf90.

I think both compilers are right; or to be more precise: The program is wrong/undefined.

If one removes the INTERFACE blocks and puts the subroutines into below a CONTAINS in the main program, gfortran gives the following error:


      call adsorb(tsl, gamm, adwat, wsc, dime = ns, mode = 1)
                 1
Error: Type/rank mismatch in argument 'te' at (1)

The actual argument "tsl" is REAL, DIMENSION(10);
the dummy argument "te" is REAL, INTENT(IN)  :: gam, te

Analogously for gam(m) and adwat/adsor.

Thus: The compiler expects in the main program that it has to pass an array, but the routine only accepts a single real.

What happens in your program is now highly platform and compiler dependent:
pgf90 seems to set all values to "0.5104298" (but I wouldn't rely on this happening all the times), gfortran has seemingly "0.5104298" in adwat(10) only. (The rest is uninitialized.) And ifort/g95 have for the whole array adwat(:) uninitialized values.

By the way, NAG f95 detects the interface/procedure mismatch also for the original program as the interface and the subroutines are in the same file. This same-file error detection is also planed for gfortran.

(In reply to comment #2)
> (In reply to comment #0)

> By the way, NAG f95 detects the interface/procedure mismatch also for the
> original program as the interface and the subroutines are in the same file.
> This same-file error detection is also planed for gfortran.
> 

K'aro Deji,

Or, more succinctly, the array in the interface is assumed shape, dimension (:), whereas you have an automatic array in the subroutine.

Change to

   SUBROUTINE adsorb2(te, gam, adsor, scl, dqdt, dime, mode)

      IMPLICIT NONE

      INTEGER, INTENT(IN) :: mode, dime
      REAL, INTENT(IN), DIMENSION(:)  :: gam, te
      REAL, INTENT(OUT), DIMENSION(:) :: adsor
      REAL, DIMENSION(:), OPTIONAL    :: dqdt, scl
      REAL, DIMENSION(dime) :: kstar, param
      REAL :: rhog, rgasv

and your program will work fine.

As Tobias says, we will be adding the means to diagnose this, just as soon as yours truly gets some time:)

I would strongly recommend that your regroup your subroutiens and the interface into a module, thusly:

module adsorbers
  interface adsorb
    module procedure adsorb, adsorb2
  end interface adsorb
contains

   SUBROUTINE adsorb2(te, gam, adsor, scl, dqdt, dime, mode)

      IMPLICIT NONE

      INTEGER, INTENT(IN) :: mode, dime
      REAL, INTENT(IN), DIMENSION(:)  :: gam, te
      REAL, INTENT(OUT), DIMENSION(:) :: adsor
      REAL, DIMENSION(:), OPTIONAL    :: dqdt, scl
      REAL, DIMENSION(dime) :: kstar, param
      REAL :: rhog, rgasv
      REAL, PARAMETER :: as = 1.7E4, mi = 2.84E-7, ko = 7.54E-9, re = 0.4734

      rhog  = 1650.0
      rgasv = 0.461510E+03

      kstar = ko * exp(2697.2 / te)
      param = kstar * gam * rgasv * te
      adsor = rhog * as * mi * (param / (1.0 + param))**re

      if (mode == 2) return

      scl = re * adsor / ((1.0 + param) * gam)

      if (mode == 1) return

       dqdt = re * adsor * (te-2697.2) / ((1.0 + param)*te*te)

      RETURN
   END SUBROUTINE adsorb2

   SUBROUTINE adsorb(te, gam, adsor, scl, dqdt, dime, mode)

      IMPLICIT NONE

      INTEGER, INTENT(IN) :: mode, dime
      REAL, INTENT(IN)  :: gam, te
      REAL, INTENT(OUT) :: adsor
      REAL, OPTIONAL    :: dqdt, scl
      REAL :: kstar, param
      REAL :: rhog, rgasv
      REAL, PARAMETER :: as = 1.7E4, mi = 2.84E-7, ko = 7.54E-9, re = 0.4734

      rhog  = 1650.0
      rgasv = 0.461510E+03

      kstar = ko * exp(2697.2 / te)
      param = kstar * gam * rgasv * te
      adsor = rhog * as * mi * (param / (1.0 + param))**re

      if (mode == 2) return

      scl = re * adsor / ((1.0 + param) * gam)

      if (mode == 1) return

       dqdt = re * adsor * (te-2697.2) / ((1.0 + param)*te*te)

      RETURN

   END SUBROUTINE adsorb
end module adsorbers

   PROGRAM adsorb_test 
      use adsorbers
      IMPLICIT NONE

      REAL, DIMENSION(10)   :: tsl, gamm, adwat, wsc
      INTEGER :: dime, mode, ns, k
      REAL    :: gams, ts, adwatg

      ns = 10
      do k = 1,ns
         tsl(k)  = 180.0
         gamm(k) = 1.50E-6
      enddo
      gams = gamm(1)
      ts   = tsl(1)

      call adsorb(ts, gams, adwatg, dime = 1, mode = 2)
      call adsorb(tsl, gamm, adwat, wsc, dime = ns, mode = 1)

      do k = 1,ns
         write(*,*) tsl(k), gamm(k), adwat(k)
      enddo
      write (*,*) "---------"
      write(*,*) ts, gams, adwatg

      stop
   END PROGRAM adsorb_test


Odabo

Paul

(In reply to comment #3)
> (In reply to comment #2)
> > (In reply to comment #0)
> 
> > By the way, NAG f95 detects the interface/procedure mismatch also for the
> > original program as the interface and the subroutines are in the same file.
> > This same-file error detection is also planed for gfortran.
> > 
> 
> K'aro Deji,
> 
> Or, more succinctly, the array in the interface is assumed shape, dimension
> (:), whereas you have an automatic array in the subroutine.
> 
> Change to
> 
Effecting the change Paul suggested fixed it for me, Thanks all. The interface and the subroutine are in different files in the original code.

Deji