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From: "marxin at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/109031] csmith: possible bad code with -O2
 -fno-strict-aliasing since r13-254-gdd3c7873a61019e9
Date: Thu, 09 Mar 2023 10:35:08 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109031

--- Comment #27 from Martin Li=C5=A1ka <marxin at gcc dot gnu.org> ---
Polished a bit more into:

unsigned char f =3D 0;

int main() {
  unsigned g =3D 0;

  unsigned *p1 =3D &g;
  unsigned char *p2 =3D &f;

  do {
    (*p1)++;
    (*p2)--;
  } while (f);

  __builtin_printf ("g=3D%u\n", g);
  if (g !=3D 256)
    __builtin_abort();
  return 0;
}=