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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/110903] [14 Regression] Dead Code Elimination
 Regression since r14-1597-g64d90d06d2d
Date: Fri, 04 Aug 2023 17:58:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110903

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note the original testcase has some obvious use of an uninitialized variabl=
e.
Anyways here is a fixed up testcase which does not have that uninitialized
variable and GCC 13 was able to optimize away the call to foo still:
```
void foo(void);
static signed char b, c;
static short e, f;
static int g =3D 41317;
static int(a)(int h, int i) { return h + i; }
static int(d)(int h, int i) { return i ? h : 0; }
short t =3D 10;
int main() {
    {
        signed char j;
        short k =3D t;
        for (; g >=3D 10; g =3D (short)g) {
            _Bool l =3D 1;
            int m =3D 0;
            j =3D 8 * k;
            k =3D j <=3D 0;
            f =3D c + 3;
            for (; c < 2; c =3D f) {
                signed char n =3D 4073709551615;
                if (!(((m) >=3D 0) && ((m) <=3D 0))) {
                    __builtin_unreachable();
                }
                if (g)
                    ;
                else {
                    if ((m =3D k, (b =3D a(d(l, k), e) && n) || l) < k) foo=
();
                    e =3D l =3D 0;
                }
            }
        }
    }
}
```=