[Bug tree-optimization/65752] Too strong optimizations int -> pointer casts

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65752

--- Comment #56 from Richard Biener <rguenth at gcc dot gnu.org> ---
Testcase from PR82177:

#include <stdio.h>
#include <stdint.h>

void f(int*, int*);

int main()
{
  int a=0, y[1], x = 0;
  uintptr_t pi = (uintptr_t) &x;
  uintptr_t yi = (uintptr_t) (y+1);
  uintptr_t n = pi != yi;

  if (n) {
    a = 100;
    pi = yi;
  }

  if (n) {
    a = 100;
    pi = (uintptr_t) y;
  }

  *(int *)pi = 15;

  printf("a=%d x=%d\n", a, x);

  f(&x,y);

  return 0;
}