#include <stdio.h>

int* f(int x) {
  int *p;
  if (x) {
    int y = 3;
    p = &y; /* ok */
    printf ("y=%d and *p=%d\n", y, *p);
  } /* ok, but p now dangling */
  printf ("*p=%d\n", *p);
  /* y = 4 does not compile */

  *p = 7; /* could CRASH but probably not */
  printf ("*p=%d\n", *p);
  return p; /* uh-oh, but no crash yet */
}

void g(int *p) { 
  *p = 123;
  f(123);  // now just to demonstrate the stack 
  printf ("in g: *p=%d\n", *p);
}

int main(int argc, char **argv) {
  g(f(7)); /* HOPEFULLY YOU CRASH (but maybe not) */
}