From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F4218C282D7 for ; Sat, 2 Feb 2019 16:36:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD9ED20823 for ; Sat, 2 Feb 2019 16:36:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SZN/bb0H" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726429AbfBBQgt (ORCPT ); Sat, 2 Feb 2019 11:36:49 -0500 Received: from mail-wr1-f67.google.com ([209.85.221.67]:33006 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725828AbfBBQgt (ORCPT ); Sat, 2 Feb 2019 11:36:49 -0500 Received: by mail-wr1-f67.google.com with SMTP id a16so4671947wrv.0 for ; Sat, 02 Feb 2019 08:36:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=nXLI8J5mAYp38Uy55BxCgwyVS0uxNhpnnCfoO+B+9ro=; b=SZN/bb0HNhPZmNuCmr6xLE8mg6Vbifn4+dOzkzx9sPsJ7JsWF4WgK9LpvUWT9Bi6DK 9ejnopo8mfcfXGwx5GZcCJ+KdCzudj9WUjlfjiDagxVv0pZgzc+T2P9drRr3B23Vu6eg dkFhoqebTgFRZQPB5T//pj1fVqaGUtl6sQIROGglOo1DtJ1BXZy2Mn42baQuKmi+csuy lgUmYJH7xCL5PUQCAfBoLY0yh9cs81CxU1mcyse1U/KrRiNtvw2SrmklBdc+ePnm5srN pSGqccDA6kul3FgeKtCkGfvQ5Zwz1SBVTQVI8lcwEILg1sAjFumLgIsLOHzNfte5HzGZ lIHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=nXLI8J5mAYp38Uy55BxCgwyVS0uxNhpnnCfoO+B+9ro=; b=iPEuTcqiTsqmRs1CrvxlAXhMh87nA3Vs8g1nkKB9v0wW878DwAUY5O8E6hDF5ilMxO PPC6Cnth2KaWrk1p0jRvEe3XSAm9pVJNdcLMDYHpJyyr0pNwe+C4ThhFc3xyxilV1myz avJPUymnUYBlE1YxMY1HrbOy+9ZUR9bZpR+vwtN7Il94lV8ndTwY0e103pA+qkZmWJz/ KAbDGTssQWgtnLRmNmmh7rlj0nFSettJRN3eZ4hVvxtdC2bYkVf5LWX4fhr6dPftPUwL I68Q/jMKcCbgszdkrk8o/7h0B81qKdqQ6ZaCHAndXreYkMqBwyQUTsgrgo9c2Oo84nJR L07Q== X-Gm-Message-State: AJcUukcCaFqmDUbECfvp32gaU3Vh3T2IY/4f80ExHmpXcIAwJtQNV6Fw ZgXtsJ1LQj5OmFyMpKxoYQ== X-Google-Smtp-Source: ALg8bN4x9hydasl3iGZMt9bjU3sQS1lejsX8LIKm2Oobdb1qzb9EMHSaOX6kIs62spl7lESqhW6TBw== X-Received: by 2002:adf:9061:: with SMTP id h88mr42632146wrh.65.1549125407331; Sat, 02 Feb 2019 08:36:47 -0800 (PST) Received: from avx2 ([46.53.245.251]) by smtp.gmail.com with ESMTPSA id z11sm6885423wmb.45.2019.02.02.08.36.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 02 Feb 2019 08:36:46 -0800 (PST) Date: Sat, 2 Feb 2019 19:36:44 +0300 From: Alexey Dobriyan To: Masahiro Yamada Cc: Andrew Morton , Zhang Yanmin , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] linux/kernel.h: use 'short' to define USHRT_MAX, SHRT_MAX, SHRT_MIN Message-ID: <20190202163644.GB28518@avx2> References: <1549123585-13800-1-git-send-email-yamada.masahiro@socionext.com> <20190202163105.GA28518@avx2> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190202163105.GA28518@avx2> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 02, 2019 at 07:31:05PM +0300, Alexey Dobriyan wrote: > On Sun, Feb 03, 2019 at 01:06:24AM +0900, Masahiro Yamada wrote: > > The log of commit 44f564a4bf6a ("ipc: add definitions of USHORT_MAX > > and others") did not explain why it used (s16) and (u16) instead of > > (short) and (unsigned short). > > > > Let's use (short) and (unsigned short), which is more sensible, and > > more consistent with the other MAX/MIN defines. > > > > As you see in include/uapi/asm-generic/int-ll64.h, s16/u16 are > > typedef'ed as signed/unsigned short. So, this commit does not have > > a functional change. > > > -#define USHRT_MAX ((u16)(~0U)) > > -#define SHRT_MAX ((s16)(USHRT_MAX>>1)) > > -#define SHRT_MIN ((s16)(-SHRT_MAX - 1)) > > +#define USHRT_MAX ((unsigned short)(~0U)) > ^ ^ > +---+ > unnecessary () > > +#define SHRT_MAX ((short)(USHRT_MAX>>1)) > > +#define SHRT_MIN ((short)(-SHRT_MAX - 1)) > > "short" and "unsigned short" are probably the most useless C types. > I doubt their usage should be promoted. OTOH, U16_MAX etc exist and cast to u16, so using "short" would be the right thing to do.