/*---------A.h-----------*/
#ifndef _A_H
#define _A_H

#include "B.h"
typedef struct A A;
struct A
{
        B * b;
};
#endif

/*-------------B.h-------------*/
#ifndef _B_H
#define _B_H

#include "A.h"
typedef stuct B B;
struct B
{
        A * a;
};
#endif

/*-----------main.c------------*/
#include "A.h"
#include "B.h"

main()
{
        struct A alfa;
        struct B vita;
}