Question

#include<stdio.h>
int* check(int,int);

int main()
{
    int *c,t = 2;
    c = check(10,20);
    printf("t = %d\n",t);
    printf("c = %d\n",*c);

    return 0;

}

int* check(int i,int j)
{
    int *p,*q;

    p = &i;
    q = &j;

    if(i>=45)
       return (p);
    else
       return (q);
}

I’m getting the output of code as :

t = 2
c = 2

why? because according to the concept the value returned to c is j address i.e. value of *c is 20 but as there is a printf statement preceding to the c’s printf statement, therefore, the value of the *c should have been some garbage value as stack is changed.

can anyone help me at this ? Please Help !!

Answer 1

It is the case of Dangling Pointer. Referencing Dangling pointers is Undefined when may give any unpredictable value.