How to dereference the pointer returned by a function?

#include <stdio.h>

int *sum_returning_pointer(int *x, int *y)
{
    // Call be reference
    int z = (*x) + (*y);
    return &z;
}

void main(int *argc, char *argv[])
{
    int a = 1, b = 2;
    int *p = sum_returning_pointer(&a, &b);
    printf("Sum = %d\n", *p);
}

With the above function i'm trying to add up the two numbers which are passed as a reference to the called function and returning pointer pointing to the variable where sum is stored. But i'm getting weird error saying.

Error has occured.
Segmentation Fault.

What does this error mean? How can i achieve a solution ? Why does this error occurs ?

In main function z is not accessible that's why it is showing undefined behavior. You can declare z as a global variable like

#include <stdio.h>
int z =0;
int * sum_returning_pointer(int *x, int *y)
{
// Call be reference
z = (*x) + (*y);
 return &z;
 }

  void main(int *argc, char *argv[])
  {

   int a = 1, b = 2;
   int *p = sum_returning_pointer(&a, &b);
   printf("Sum = %d\n", *p);
   }