This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: Fix log10 (1) in round-downward mode (bug 16977)
- From: Andreas Jaeger <aj at suse dot com>
- To: "Joseph S. Myers" <joseph at codesourcery dot com>, libc-alpha at sourceware dot org
- Date: Fri, 23 May 2014 09:17:09 +0200
- Subject: Re: Fix log10 (1) in round-downward mode (bug 16977)
- Authentication-results: sourceware.org; auth=none
- References: <Pine dot LNX dot 4 dot 64 dot 1405230054590 dot 10376 at digraph dot polyomino dot org dot uk>
On 05/23/2014 02:55 AM, Joseph S. Myers wrote:
> As with various other issues of this kind, bug 16977 is log10 (1)
> wrongly returning -0 rather than +0 in round-downward mode because of
> an implementation effectively in terms of log1p (x - 1). This patch
> fixes the issue in the same way used for log.
>
> Tested x86_64 and x86 and ulps updated accordingly. Also tested for
> mips64 to confirm a fix was needed for ldbl-128 and to validate that
> fix (also applied to ldbl-128ibm since that version of logl is
> essentially the same as the ldbl-128 one).
Thanks,
Andreas
--
Andreas Jaeger aj@{suse.com,opensuse.org} Twitter: jaegerandi
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn,Jennifer Guild,Felix Imendörffer,HRB16746 (AG Nürnberg)
GPG fingerprint = 93A3 365E CE47 B889 DF7F FED1 389A 563C C272 A126