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From: "liuhongt 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: Mon, 18 Mar 2024 09:08:32 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114347

--- Comment #9 from Hongtao Liu <liuhongt at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #7)
> (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.
> > You'd need (int) (__bf16) 257.0bf16 to get 256 even with excess precisi=
on.
>=20
> Ah, -fexcess-precision=3D16 doesn't seem to be documented though (how does
> this influence long double handling then?)

Oh, I forgot to add that in invoke.texi.

-fexcess-precision=3D16 doesn't impact types with precision > 16. And it's =
not
compatible with -mfpmath=3D387.=