strange behavior of a mixed C/fortran code on a sun4m

[Maxime baudin <baudin@cnam.fr>]

Hi,
Here is a really strange behavior of function call
on a sun4m sparc


I must precise that this problem does not appear
on our i386 PC or Alpha (running linux too)

I have a main programme written in C
It calls a Fortran function 

The programme must simply calculate the exponantial of a complex
value.

The strange behavior is in the argument "pass"
The call is :

b = f77exp_(&a)

In the Fortran function I have :
complex*16 function F77EXP(ARGUMENT)

where ARGUMENT should be the address of 'a'

unfortunately, ARGUMENT got 'b' address and return 'a' address !!



STRANGE !

here is the code, an the compilation lign :

/* appelc.c */
#include <stdio.h>
#include <stdlib.h>

typedef double real8;
typedef struct complexe16
{
    real8               partie_reelle;
    real8               partie_imaginaire;
} struct_complexe16;

typedef struct_complexe16   complex16;

complex16 f77exp_(complex16 *argument);

int
main()
{
        complex16               a;
        complex16               b;

        a.partie_reelle = 1;
        a.partie_imaginaire = 1;
        a = f77exp_(&b);

        printf("%d %d\n", b.partie_reelle, b.partie_imaginaire);
        return(0);
}


/* exp.f */

      complex*16 function F77EXP(ARGUMENT)

      implicit none

      complex*16 ARGUMENT

      write(*,*) ARGUMENT
      F77EXP = exp(ARGUMENT)

      return

      end function



/* compilation ligns */
g77 -g -c appelc.c
g77 -g -c exp.f
g77 -g -o crashtest exp.o appelc.o



If someone can explain this to me....
-- 
Baudin Maxime - Laboratoire électronique et communication - CNAM, Paris
Le paradis c'est rempli de gens qui pendant l'éternité entière, vont se
raconter des souvenirs de leurs vies. L'enfer c'est pareil...
sauf qu'en plus chacun apporte ses diapos.