error #8127

[Ketson_Roberto]

Dear all,

I am having a problem while I am trying to run my program as debug. 

I am facing the following error: error #8127: A null argument is not permitted when calling a Fortran routine which has an explicit interface defined.    

I am not sure what is happening because in the release mode every thing work properly. 

Thank you all in advance!

[Steven_L_Intel1]

Without seeing source, it's hard to know exactly what is going on. But I can reproduce this error with the following source:

call sub (1,,2)
end
subroutine sub (a,b,c)
integer a,b,c
end subroutine sub

and compiling with /warn:interface, which is enabled in a Debug configuration. Are you using the ,, syntax in a call? Is that deliberate?

[Ketson_Roberto]

Thank you Steve the  /warn:interface option works well. And I am using the null option as the last dummy argument, but now almost everything is ok.

[Steven_L_Intel1]

Instead of the null option, use %VAL(0) - it will do the same thing and won't trigger the error. Ideally you'd be using explicit interfaces and OPTIONAL instead of that non-standard feature.

[Ketson_Roberto]

Thank you Steve I will try to do this on my code!

[Ketson_Roberto]

Steve, could you help me to understand this error:

error #6633: The type of the actual argument differs from the type of the dummy argument.   [DFIT_OPT]    

 SUBROUTINE PROBABILITY_DISTRIBUTION_BEST_FIT(IRV,SELECTED_CRV,DFIT_OPT)
        
!-----------------------------------------------------------------------
!   EXTERNAL VARIABLES
!
! FIT_OPTION  Integer that indicates fit option:
!                1 = Minimum squares differ. fit (minimizes CHI-SQUARES goodness_of_fit test)
!                2 = Minimum CDF difference  fit (minimizes KOLMOGOROV  goodness_of_fit test)
!         IRV  Interpolated random variable to be fitted
!         CRV  Continuous random variable resulting from the fit
!   DFIT_OPT  Options for analytical distribution fit
!-----------------------------------------------------------------------

    IMPLICIT NONE

!    INTEGER FIT_OPTION

    TYPE(INTERPOLATED_RANDOM_VARIABLE),INTENT(IN) :: IRV

    TYPE(        CONT_RANDOM_VARIABLE),INTENT(INOUT) :: SELECTED_CRV

    TYPE(RESP_DIST_FIT_OPTIONS),       INTENT(IN) :: DFIT_OPT

!-----------------------------------------------------------------------
!   INTERNAL VARIABLES
!
!       CRV  Vector of continuous random variables containing trial fitting results
!  GOF_TEST  Goodness of fit of trial results, the trial with best GOF result gets selected 
!-----------------------------------------------------------------------

    INTEGER        :: I = 1, N_TRIALS = 1

    TYPE(CONT_RANDOM_VARIABLE) :: CRV(DFIT_OPT%N_TRIALS)

    REAL*8 GOF_TEST(DFIT_OPT%N_TRIALS)

    GOF_TEST = 0.D0

    N_TRIALS = DFIT_OPT%N_TRIALS

    DO I=1, N_TRIALS
    
        CALL PROBABILITY_DISTRIBUTION_SINGLE_FIT(DFIT_OPT%TRIAL_DISTRIBUTION(I),DFIT_OPT,IRV,CRV(I)) !THE ERROR IS HERE

....

END MODULE CLASS_PROBABILITY_DISTRIBUTION_FIT

Then the subroutine is:

    SUBROUTINE PROBABILITY_DISTRIBUTION_SINGLE_FIT(FIT_CODE,DFIT_OPT,IRV,RESULT_CRV)

    USE STRAND_GLOBAL_VARIABLES
        
    USE CLASS_PROBABILITY_PAPER

    USE CLASS_PROBABILITY_DISTRIBUTION_FIT

    USE LINEAR_DISTRIBUTION_FIT

    USE NONLINEAR_DISTRIBUTION_FIT

!-----------------------------------------------------------------------
!   EXTERNAL VARIABLES
!
!    FIT_OPTION  Integer that indicates fit option:
!                    1 = Minimum squares differ. fit (minimizes CHI-SQUARES goodness_of_fit test)
!                    2 = Minimum CDF difference  fit (minimizes KOLMOGOROV  goodness_of_fit test)
!      FIT_CODE  Code of probability distribution to fit
!       DFIT_OPT  Options for analytical distribution fit
!            IRV  Interpolated random variable to be fitted
!     RESULT_CRV  Continuous random variable resulting from the fit
!      GOF_TEST  Goodness of fit of result
!-----------------------------------------------------------------------

    IMPLICIT NONE

    INTEGER,                           INTENT(IN) :: FIT_CODE
    
    TYPE(RESP_DIST_FIT_OPTIONS),       INTENT(IN) :: DFIT_OPT

    TYPE(INTERPOLATED_RANDOM_VARIABLE),INTENT(IN) :: IRV

    TYPE( CONT_RANDOM_VARIABLE),INTENT(INOUT) :: RESULT_CRV

...

END SUBROUTINE PROBABILITY_DISTRIBUTION_SINGLE_FIT

Thank you all!

[Steven_L_Intel1]

I don't see anything wrong with that code.  Try this - do a Build > Rebuild Solution and see if the error goes away.

[Ketson_Roberto]

I still have problem with null arguments and optional. Could you take a look?

This is the call procedure: 

CALL TIME_VARIANT_RELIABILITY_OLD(NRV,RP_SET,RP_TIME,RP_RESULT,XMDX(1:NRV), )

This is the subroutine:

SUBROUTINE TIME_VARIANT_RELIABILITY_OLD(NRV,RP_SET,RP_TIME,RP_RESULT,R_OUTCOME,RV_SET)

!-----------------------------------------------------------------------
!    EXTERNAL VARIABLES:
!    
!            NRV    Number of continuous random process
!         RP_SET    
!      R_OUTCOME    Outcome of resistance variables, generated by MCS or by FPI
!        RP_TIME    Vector of time variant reliability information
!      RP_RESULT Results of time variant reliability analysis
!         RV_SET Random variable set, optional, only needed for ENSEMBLE CROSSING RATE
!                                                       failure probability evaluation
!-----------------------------------------------------------------------

    IMPLICIT NONE

    INTEGER,                    INTENT(IN) :: NRV

    TYPE(RANDOM_PROCESS_SET),   INTENT(IN) :: RP_SET

    TYPE(RP_RELIABILITY_TIME),  INTENT(IN)    :: RP_TIME
    TYPE(RP_RELIABILITY_RESULT),INTENT(INOUT) :: RP_RESULT

    REAL(8),INTENT(IN) ::        R_OUTCOME(NRV)

    TYPE(RANDOM_VARIABLE_SET),INTENT(IN), OPTIONAL :: RV_SET

...

END SUBROUTINE TIME_VARIANT_RELIABILITY_OLD

This is the error:

error #8127: A null argument is not permitted when calling a Fortran routine which has an explicit interface defined.   [TIME_VARIANT_RELIABILITY_OLD]  

I cannot see where is the error. An interesting fact is that the release mode works properly, unlike the Debug mode. This error appear when I am in the Debug mode.

Thank you again.

Ketson Roberto

[Steven_L_Intel1]

If you want to use OPTIONAL, just leave off the last argument, don't use a comma with nothing after it. An explicit interface is required to be visible to the caller. Make sure that you test for presence of the optional argument with PRESENT() before using it.