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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/114347] wrong constant folding when casting __bf16
 to int
Date: Wed, 20 Mar 2024 06:19:17 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114347

--- Comment #11 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Paul Eggert from comment #10)
> (In reply to Jakub Jelinek from comment #6)
> > You can use -fexcess-precision=3D16 if you don't want treating _Float16=
 and
> > __bf16 as having excess precision.  With excess precision, I think the =
above
> > behavior is correct.
>=20
> So the constant 257.0bf16 has a value that the type __bf16 cannot represe=
nt?
> Although the C standard allows this sort of thing, it doesn't sound wise.

This is also true for similar case for 32bit x86 (without using SSE) and
constants ending in f or other floating point constants. Just folks hit it
there as much as that is not used as much either.=