GCC generates the wrong instructions when I write a function which returns a reference to a local variable?

Question

Even I have similar problem:

int (*pfun)(void);
int *pInt = 0;
void fun1()
{
    int i = 5; /* Local to fun1*/

    printf("Outer function");
    pInt = &i; /* As I know address of local variable is valid till function execution */

    int fun2()
    {
      printf("innerfunction");
      printf("%d", *pInt);
    }
    /* fun2 address assign to pfun so that It can be called even after completion of fun1 */
    pfun = fun2;
}

int main()
{
    fun1();
    pfun();
    return 0;
}

Can someone please explain ? I am getting *pInt value 5.

Answer 1

The compiler has generated the right instructions. What you are doing is not defined by the C standard, so the compiler is free to do whatever it pleases. In this case it seems that GCC pleases to return a null pointer, probably so that your program will fail as fast as possible.