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From: "aldyh at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/101912] -Wmaybe-uninitialized false alarm in
 tzdb localtime.c
Date: Tue, 30 Nov 2021 16:02:39 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101912

--- Comment #3 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---

>               && !(leapcnt =3D=3D 0
>                    || (prevcorr < corr
>                        ? corr =3D=3D prevcorr + 1
>                        : (corr =3D=3D prevcorr
>                           || corr =3D=3D prevcorr - 1)))))
>=20

I guess the question is whether language rules allow us to read prevcorr wh=
en
leapcnt=3D=3D 0?

Like we're doing here:

> and after ifcombine we have:
>=20
>   <bb 4> [local count: 996582262]:
>   _1 =3D corr_14 =3D=3D 1;
>   _2 =3D leapcnt_5 !=3D 0;
>   _3 =3D _1 & _2;
>   _19 =3D prevcorr_4 !=3D 1;
>   _16 =3D _3 & _19;
>   _21 =3D prevcorr_4 !=3D 2;
>   _18 =3D _16 & _21;
>   if (_18 !=3D 0)
>     goto <bb 7>; [1.21%]
>   else
>     goto <bb 5>; [98.79%]=