[Bakhbergen]

Dear Fortran Users,

I need to create and use dynamic-link library (DLL) for Fortran application using Compaq Visual Fortran 6.6. The following code works just fine:

###########################################
PROGRAM AMAIN1
IMPLICIT NONE
REAL(8):: A,B,S
A = 1D0
B = 2D0
CALL SUBRO1(A,B,S)
PRINT*, 'S = ', S
END PROGRAM AMAIN1
###########################################
SUBROUTINE SUBRO1(A,B,S)
!DEC$ ATTRIBUTES DLLEXPORT :: SUBRO1
IMPLICIT NONE
REAL(8):: A,B,S
S = A + B
RETURN
END SUBROUTINE SUBRO1
###########################################
The result is correct:
S = 3.00000000000000
Press any key to continue
###########################################

However, if I implement the same algorithm using the module, I get inconsistent result (i.e. zero):

###########################################
PROGRAM AMAIN2
USE MODUL2
IMPLICIT NONE
A = 1D0
B = 2D0
CALL SUBRO2
PRINT*, 'S = ', S
END PROGRAM AMAIN2
###########################################
MODULE MODUL2
IMPLICIT NONE
REAL(8):: A,B,S
END MODULE MODUL2
###########################################
SUBROUTINE SUBRO2
!DEC$ ATTRIBUTES DLLEXPORT :: SUBRO2
USE MODUL2
IMPLICIT NONE
S = A + B
RETURN
END SUBROUTINE SUBRO2
###########################################
The result is incorrect:
S = 0.000000000000000E+000
Press any key to continue
###########################################

As can be seen above, DLL contains only subprogram in both cases (SUBRO1 and SUBRO2, respectively). I have built DLL and LIB files from the visual development environment. The second case (with the use of module) represents the structure of my large source-code so I need to resolve this issue. Any advice would be greatly appreciated.