From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f65.google.com (mail-wm0-f65.google.com [74.125.82.65]) by dpdk.org (Postfix) with ESMTP id 87BD514EC for ; Tue, 31 Jul 2018 18:48:58 +0200 (CEST) Received: by mail-wm0-f65.google.com with SMTP id r24-v6so11529544wmh.0 for ; Tue, 31 Jul 2018 09:48:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=6wind-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=uL1VVgjjzSI+8IBoVSMPH3MJYL7NrD3FdohNXPllgYY=; b=yba7ubctbI9GHM4c+GlZxM6+t4evT7TwS9c1Khw2smqhrt2hE3Sz60gTD1t6G7HfVQ 9y3HUvWtieJd/qlgLqfsRqFaicbAgy/HAfADYhJlr2Dtsw1Ldf+mGNq0bjsNSDwyec91 ZoG3QaGJ4Ml06VZ7TweKwZxNYhM/ifjdaOsrTtSu6FrSxLtWgAR/0JAHR9X7BVrQOimj wXOv8d+toq9msl9zLEi9hE7UDhgUoaP84WraRKsBFoAWp83zDBDKULhLjAZRliRFoZzq JT2o/SA6yWwcSevbgtje0/OspqqCyLiB0sD/R+a0lQww4zTusXpeMdfn4T/iVt9aONhN hlkA== 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; bh=uL1VVgjjzSI+8IBoVSMPH3MJYL7NrD3FdohNXPllgYY=; b=dOXYOhHpBIYXQc9Wbi19v3ZUyms3+Z3x0mENR70wJ9WG4xVmUl+xWSlSUDst49pgNb Upw+XEQ9e77+lQlVDtZjkRnEPhO7zb2W3LxXOMswgbxEkxHfQyZMssyDL4zXICfUBoRW YD7JirnJpvagVNOAuj5Nuqd2y93luSHei0HAx6wHWCxLg5tMD9NVEav/5daJvKDxtFJ3 9S8vTncgzRH8MBXu/7piStgZkWGfGdWHC14gbLdZQLp1+o/wkAGIZZuJ1FoaSMm4QMsd RZgOo7mVXNOQEN70S06manrUoasdt/4VlKqA9/1kYd52eBbUY25kk8UVM6/tQLKiE9pJ ozPw== X-Gm-Message-State: AOUpUlHFh2kQRYHvwUYwsikuQ7KhZL82EKlcwKCncBsNn//t69WZnrbP CbLu9lXahk0TtztLsCHjUw+QgfkM9MhGTQ== X-Google-Smtp-Source: AAOMgpfdxNZhXR486usTCMYKUn76IbB3j9555XcfBupol6Mqh9QA0IFmsshb6caVJo+coV6rkQduZA== X-Received: by 2002:a1c:8893:: with SMTP id k141-v6mr339113wmd.36.1533055738237; Tue, 31 Jul 2018 09:48:58 -0700 (PDT) Received: from 6wind.com (host.78.145.23.62.rev.coltfrance.com. [62.23.145.78]) by smtp.gmail.com with ESMTPSA id d7-v6sm17234791wro.92.2018.07.31.09.48.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 31 Jul 2018 09:48:57 -0700 (PDT) Date: Tue, 31 Jul 2018 18:48:40 +0200 From: Adrien Mazarguil To: Stephen Hemminger Cc: dev@dpdk.org Message-ID: <20180731164840.GD5211@6wind.com> References: <20180731163059.27085-1-stephen@networkplumber.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180731163059.27085-1-stephen@networkplumber.org> Subject: Re: [dpdk-dev] [PATCH 0/5] remove usage of register keyword in C X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Jul 2018 16:48:58 -0000 On Tue, Jul 31, 2018 at 09:30:54AM -0700, Stephen Hemminger wrote: > Declaring variables as register in C is a leftover from an earlier > era (like cassette tape decks in cars). I don't agree here. It's a hint for compilers and developers that the address of such variables won't be needed (and cannot be taken) to enable whatever optimizations are possible knowing this. Somewhat like inline functions, it's not a forced optimization, just a useful hint that shouldn't hurt if used wisely. Besides, cassette decks are not dead yet :) -- Adrien Mazarguil 6WIND