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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/110251] [14 Regression] Hang at -O3 on
 x86_64-linux-gnu
Date: Thu, 15 Jun 2023 04:32:37 +0000
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X-Bugzilla-Component: tree-optimization
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X-Bugzilla-Keywords: compile-time-hog
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110251

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Looks like it is uninitialized variable related.
Here is one which shows that:
```
int a, b;
char c;
int d(int e) {
  int t =3D 0;
  if (e >=3D 'a')
    return e;
  return t;
}
int f(unsigned short e) {
  int t2;
  for (; e; a++)
    e &=3D e - 1;
  return t2;
}
void g() {
  for (; c < 1;)
    ;
  for (; f(c - 1); b =3D d(c))
    ;
}
```

If you initialize t2 to either 1 or 0, GCC will not hang.=