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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/110228] [13/14 Regression] llvm-16 miscompiled due
 to an maybe uninitialized variable
Date: Sat, 01 Jul 2023 21:50:23 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110228

--- Comment #23 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #22)
> (In reply to Zhendong Su from comment #21)
> > Another very likely related reproducer.
> Yes:
>   <bb 3> [local count: 82077551]:
>   a.0_1 =3D a;
>   _27 =3D a.0_1 =3D=3D 0;
>   _5 =3D (int) _27;
>   _28 =3D _5 | i_14;
>   pretmp_45 =3D b;
> ...
>   <bb 7> [local count: 200189151]:
>   # i_14 =3D PHI <i_19(D)(2), i_13(6)>

I wonder if ccp1 in this case could cause the 1 to proped out of the loop. =
and
maybe we need some more isolation going on when it comes to using uninitial=
ized
variables ...=