From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 4390 invoked from network); 16 May 2020 21:07:07 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 16 May 2020 21:07:07 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 003A69C5EE; Sun, 17 May 2020 07:07:04 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 93B869C5E5; Sun, 17 May 2020 07:06:33 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id E18F09C5E5; Sun, 17 May 2020 07:06:29 +1000 (AEST) X-Greylist: delayed 1856 seconds by postgrey-1.36 at minnie.tuhs.org; Sun, 17 May 2020 07:06:28 AEST Received: from anduin.eldar.org (anduin.eldar.org [24.106.248.90]) by minnie.tuhs.org (Postfix) with ESMTPS id 6E0419C5E4 for ; Sun, 17 May 2020 07:06:28 +1000 (AEST) Received: from anduin.eldar.org (IDENT:brad@localhost [127.0.0.1]) by anduin.eldar.org (8.15.2/8.13.8) with ESMTPS id 04GKZPeG018178 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sat, 16 May 2020 16:35:25 -0400 (EDT) Received: (from brad@localhost) by anduin.eldar.org (8.15.2/8.13.8/Submit) id 04GKZOUQ011095; Sat, 16 May 2020 16:35:24 -0400 (EDT) From: Brad Spencer To: Paul Winalski In-Reply-To: (message from Paul Winalski on Sat, 16 May 2020 12:31:06 -0400) Date: Sat, 16 May 2020 16:35:24 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.4.3 (anduin.eldar.org [127.0.0.1]); Sat, 16 May 2020 16:35:25 -0400 (EDT) Subject: Re: [TUHS] v7 K&R C X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: tuhs@minnie.tuhs.org Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Paul Winalski writes: > On 5/15/20, Warner Losh wrote: >> >> arm has been the biggest outlier in terms of unsigned char. In FreeBSD, >> this has been the second largest source of bugs with the platform... the >> OABI weird alignment requirements being the first (thankfully behind us)... > > Why did the implementers of the Unix ABI for ARM decide to have char > be unsigned? Was there an architectural reason for it? > > -Paul W. My understanding is that it is a lot more efficient to use unsigned char on arm. You can make gcc, for example, deal with this, but it costs. I remember having to tell gcc to deal with it when I ported the Doom engine to a StrongARM processor device under NetBSD many years ago. I mostly remember the code running well enough, but it was larger. -- Brad Spencer - brad@anduin.eldar.org - KC8VKS - http://anduin.eldar.org