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From: "marxin at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/107833] wrong code at -Os and above on
 x86_64-linux-gnu since r12-5138-ge82c382971664d6f
Date: Wed, 23 Nov 2022 14:17:49 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107833

--- Comment #3 from Martin Li=C5=A1ka <marxin at gcc dot gnu.org> ---
> Isn't there an uninitialized read from "i" here?

Yes ...

>  At least on the second
> time through the outer loop, if (a < h) is true since 1 < 0.
>=20
> >         c =3D *f;
> >       }
> >     for (h =3D 0; h < 3; h++) {
> >       if (d)
> >         break;
>=20
> d is nonzero so h will always be 0 in this function.

... but as you correctly said, it's never executed as 'a < h' is always fal=
se.

>=20
> >       i--;
> >       printf("0");
> >     }
> >   }
> >   return 0;
> > }
>=20
> Unless I'm missing something....=