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Subject: [Bug c++/105534] -Wmaybe-uninitialized cases shouldn't suppress
 -Wuninitialized warnings
Date: Mon, 09 May 2022 13:51:28 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105534

--- Comment #4 from Mathias Stearn <redbeard0531 at gmail dot com> ---
(In reply to Richard Biener from comment #2)
> Note there's
>=20
>   _2 =3D value_1(D) * x_2;
>=20
> where _2 might be effectively uninitialized iff x_2 is not zero.  When x_2
> is zero then _2 has a well-defined value.

Not according to the C++ standard. http://eel.is/c++draft/basic.indet seems
pretty clear that unless x_2 is std::byte (which doesn't support
multiplication) or an "unsigned ordinary character type", then that is UB.=
=20

FWIW I still think I'd expect the warning on "unsigned char x, y; y =3D x *=
 0;",
but I would definitiely expect the warning for int.=