From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <glibc-bugs-return-27024-listarch-glibc-bugs=sources.redhat.com@sourceware.org>
Received: (qmail 31166 invoked by alias); 6 Jan 2015 11:22:15 -0000
Mailing-List: contact glibc-bugs-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <glibc-bugs.sourceware.org>
List-Subscribe: <mailto:glibc-bugs-subscribe@sourceware.org>
List-Post: <mailto:glibc-bugs@sourceware.org>
List-Help: <mailto:glibc-bugs-help@sourceware.org>, <http://sourceware.org/lists.html#faqs>
Sender: glibc-bugs-owner@sourceware.org
Received: (qmail 31134 invoked by uid 48); 6 Jan 2015 11:22:11 -0000
From: "walter.mascarenhas at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug libc/17803] New: scalblnl differs from scabnl and ldexpl (with radix 2)
Date: Tue, 06 Jan 2015 11:22:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: glibc
X-Bugzilla-Component: libc
X-Bugzilla-Version: 2.19
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: walter.mascarenhas at gmail dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter cc attachments.created
Message-ID: <bug-17803-131@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2015-01/txt/msg00049.txt.bz2

https://sourceware.org/bugzilla/show_bug.cgi?id=17803

            Bug ID: 17803
           Summary: scalblnl differs from scabnl and ldexpl (with radix 2)
           Product: glibc
           Version: 2.19
            Status: NEW
          Severity: normal
          Priority: P2
         Component: libc
          Assignee: unassigned at sourceware dot org
          Reporter: walter.mascarenhas at gmail dot com
                CC: drepper.fsp at gmail dot com

Created attachment 8046
  --> https://sourceware.org/bugzilla/attachment.cgi?id=8046&action=edit
test case illustrating the problem

It would be convenient if the functions scalbnl, ldexpl (when the radix = 2)
and scalblnl delivered the same results when the exponents were within the
common range supported by these functions. However, when rounding to nearest,
scalblnl may deliver a result that differs from the one obtained by ldexpl and
scalbnl
(please see the enclosed main.cc file)

I do not have a copy of the ISO/IEC 60559 standard and therefore I cannot tell
whether this behavior is compatible with the standard. However, there is much
confusion this point in some webpages, and it would be nice if glibc's
documentation contained a detailed description of the outupt in all possible
cases.

-- 
You are receiving this mail because:
You are on the CC list for the bug.