From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <joseph_myers@mentor.com>
Received: from esa1.mentor.iphmx.com (esa1.mentor.iphmx.com [68.232.129.153])
 by sourceware.org (Postfix) with ESMTPS id AC3CE393FC2A
 for <newlib@sourceware.org>; Tue, 17 Mar 2020 01:30:31 +0000 (GMT)
IronPort-SDR: Nj1q1kmmyGDeWQqfQUbrv7ohZY5VYdHvAu1uAT/xhKFNWPKAzjjKTbcm8BKa95DjihXZYKU/LV
 bRDJEWPdqzaiYVkr1mQBCGA48KIjyVB4EcaA/9yzRFjl1RIGJM/97ptsAvoqC+wLwSg4uw4fz/
 TEpL0b2+Jo2HIRvsLd8Oq86VAFXVOrArjoCn24n4H1lKEiqo3+5N7IlkfLWtNvY2g1B/As0VGI
 KZtQdg+sIhlyaaR7pxgk0HCF2B+7/vRgOF0Q+67sB/avWwoW+pXjjfShTrWIQrWFKkpLApFB0W
 vh4=
X-IronPort-AV: E=Sophos;i="5.70,562,1574150400"; d="scan'208";a="48740405"
Received: from orw-gwy-01-in.mentorg.com ([192.94.38.165])
 by esa1.mentor.iphmx.com with ESMTP; 16 Mar 2020 17:30:30 -0800
IronPort-SDR: ncJUh/zDFxCUjh3h/chJX0USHQL5/rbCBxs9GK90OgOQ2U92eauT8YSFRSximQ0W13NM8DFr7H
 ZI8UUgejlaItAdTyUcKLkR3iL3ThnaKUKZAmjoLcyrCLTOGhalSB5vvxsf7V6vIhL2LpJSw46t
 5OC5EpLmQY0JjQS/x0P2p6OS4p7RIPOMa/kqM937sytgGfhgV2263RdU9dT9KG6L1fGEo3JXWg
 0O6XlSFZkHOCYo9LEMlkQmN8Mm5SbVsJX6//lSN5dQXbEe8uqkoZOd/OrS/D1hOe2D6B2N5i6E
 FGQ=
Date: Tue, 17 Mar 2020 01:30:25 +0000
From: Joseph Myers <joseph@codesourcery.com>
X-X-Sender: jsm28@digraph.polyomino.org.uk
To: Keith Packard <keithp@keithp.com>
CC: <newlib@sourceware.org>, Fabian Schriever <fabian.schriever@gtd-gmbh.de>
Subject: Re: [PATCH] Fix truncf for sNaN input
In-Reply-To: <87wo7km63l.fsf@keithp.com>
Message-ID: <alpine.DEB.2.21.2003170129100.20933@digraph.polyomino.org.uk>
References: <20200311095805.582-1-fabian.schriever@gtd-gmbh.de>
 <87zhcmr52d.fsf@keithp.com>
 <alpine.DEB.2.21.2003112145291.30536@digraph.polyomino.org.uk>
 <87sgieqzub.fsf@keithp.com>
 <alpine.DEB.2.21.2003112310490.30536@digraph.polyomino.org.uk>
 <87wo7km63l.fsf@keithp.com>
User-Agent: Alpine 2.21 (DEB 202 2017-01-01)
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
X-Originating-IP: [137.202.0.90]
X-ClientProxiedBy: svr-ies-mbx-06.mgc.mentorg.com (139.181.222.6) To
 SVR-IES-MBX-03.mgc.mentorg.com (139.181.222.3)
X-Spam-Status: No, score=0.3 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,
 KAM_DMARC_STATUS, SPF_HELO_NONE,
 SPF_PASS autolearn=no autolearn_force=no version=3.4.2
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
 server2.sourceware.org
X-BeenThere: newlib@sourceware.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Newlib mailing list <newlib.sourceware.org>
List-Unsubscribe: <http://sourceware.org/mailman/options/newlib>,
 <mailto:newlib-request@sourceware.org?subject=unsubscribe>
List-Archive: <http://sourceware.org/pipermail/newlib/>
List-Post: <mailto:newlib@sourceware.org>
List-Help: <mailto:newlib-request@sourceware.org?subject=help>
List-Subscribe: <http://sourceware.org/mailman/listinfo/newlib>,
 <mailto:newlib-request@sourceware.org?subject=subscribe>
X-List-Received-Date: Tue, 17 Mar 2020 01:30:32 -0000

On Mon, 16 Mar 2020, Keith Packard via Newlib wrote:

> I was concerned with what NaN values are delivered from a NaN
> operand, given the POSIX specification which says that the operand
> itself shall be delivered if it is a NaN.

I don't think POSIX specifications should be trusted for how functions 
should behave with sNaN inputs.  Rather, prefer the specifications from TS 
18661-1 (or the latest C2x draft which has TS 18661-1 integrated).

-- 
Joseph S. Myers
joseph@codesourcery.com