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From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 17 Dec 2021 06:25:51 -0800
Message-ID: <CAMe9rOoko55u3xqYhKp3HpWoB7o70-id1jC+huQxQxJRkMVYRQ@mail.gmail.com>
Subject: Re: [PATCH] middle-end/57245 - honor -frounding-math in real
 truncation
To: Jakub Jelinek <jakub@redhat.com>
Cc: Richard Biener <rguenther@suse.de>, GCC Patches <gcc-patches@gcc.gnu.org>, 
 "Joseph S. Myers" <joseph@codesourcery.com>
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On Thu, Oct 28, 2021 at 2:23 AM Jakub Jelinek via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> On Thu, Oct 28, 2021 at 10:11:36AM +0200, Richard Biener wrote:
> > 2021-10-27  Richard Biener  <rguenther@suse.de>
> >
> >       PR middle-end/57245
> >       * fold-const.c (fold_convert_const_real_from_real): Honor
> >       -frounding-math if the conversion is not exact.
> >       * simplify-rtx.c (simplify_const_unary_operation): Do not
> >       simplify FLOAT_TRUNCATE with sign dependent rounding.
> >
> >       * gcc.dg/torture/fp-double-convert-float-1.c: New testcase.
>
> LGTM, thanks.
>
>         Jakub
>

This miscompiled libm in glibc:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103735

-- 
H.J.