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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 A33AAC43461 for ; Tue, 15 Sep 2020 20:53:03 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1751220771 for ; Tue, 15 Sep 2020 20:53:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="dF7CHAkz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1751220771 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:35602 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kIHwj-0004t4-VE for qemu-devel@archiver.kernel.org; Tue, 15 Sep 2020 16:53:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38926) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kIHvg-00046I-4t for qemu-devel@nongnu.org; Tue, 15 Sep 2020 16:51:56 -0400 Received: from mail-pg1-x544.google.com ([2607:f8b0:4864:20::544]:42996) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kIHve-0006PH-1c for qemu-devel@nongnu.org; Tue, 15 Sep 2020 16:51:55 -0400 Received: by mail-pg1-x544.google.com with SMTP id k14so2616293pgi.9 for ; Tue, 15 Sep 2020 13:51:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=54knxFfGr2vNzIjyA68twv7T9N8v2Y6Mav8bQQB0eVM=; b=dF7CHAkzfOx3+Zegyno5pwpzNfyKEHcBm5rJQ/4rW6Mjji11RIkHqEJShXte9tWcrc dFQnTRMZNZOEOdHhG0Lod69HXWuiqc8AWxM7gKGsmwcoyEMZbxypvlvGoGLpRp5sx3NP JPFd7lMfpb0TBAe+MYWwbIxlO5ZIAPVZW73h/2XTk1kT2vpcc1aKmHzLvT2vx0WlFJ4d mXNNRwI0N29IU4MoZFo9TUARIwmr2E+6Opcuhft5MyJsnR3hBO1Xy+EzjffR8kZpqrIL iRVoSHaFN18rLZBDyb43ImFzokc6UGts39kJQmBizpvviHpzMAHVY8U29VP+sGULq97Z wQDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=54knxFfGr2vNzIjyA68twv7T9N8v2Y6Mav8bQQB0eVM=; b=Oo6m+jgfEglp7Q5KAq1lY84DxzmsJpQaJQpW4LfCLXy7A/2QqW+MRpLA2YZH3JV2Ab WxHp/BJdyCK/cNyrw0wmxqANauv5MdIrIgA4KQfxuyADj2Rw4OpXjvmkig9F4kDIJbKJ j3C75K1fYFypLTDlZJl5rzoSNmRo8U//6Ls7hv/XY5tQP7fGgtV0HZagplVy1VmzZYQU HioDuJ+pzkFDzuAMVcqApK81XJ4kx9IhfYf0YATfUo3OMm5m6nvRDl7atLuC5hNSRdw1 pIHd3EDMC2FYmMq3bHG5z0QcrKgyBU8LqixlB+Rby7zLhhwrMAFLHzmpg/CL5z8RSchv wJGQ== X-Gm-Message-State: AOAM532riXNq91I8TgwPyOi0VUr809yi3zGbV7AHzCf2X/oNTwWd51lp Uysi8ggNVym1iT6qQ0vKpvaC5g== X-Google-Smtp-Source: ABdhPJzI9GuhsoApHII13KLDLFWyklxbMiyWK20jjz0E9M1wPKwu+bIsvMhcJPBx/N0lMupaDkxfJw== X-Received: by 2002:aa7:9850:0:b029:142:2501:34f0 with SMTP id n16-20020aa798500000b0290142250134f0mr3488691pfq.73.1600203112584; Tue, 15 Sep 2020 13:51:52 -0700 (PDT) Received: from [192.168.1.11] ([71.212.141.89]) by smtp.gmail.com with ESMTPSA id s8sm370781pjm.7.2020.09.15.13.51.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 15 Sep 2020 13:51:50 -0700 (PDT) Subject: Re: [PATCH 1/5] qom: Allow objects to be allocated with increased alignment To: Eduardo Habkost References: <20200915174635.2333553-1-richard.henderson@linaro.org> <20200915174635.2333553-2-richard.henderson@linaro.org> <20200915180736.GB7594@habkost.net> <6d6a80bf-a542-6818-1638-0318f4aab336@linaro.org> <20200915201901.GD7594@habkost.net> From: Richard Henderson Message-ID: <74c1e091-63c4-9ea0-c515-ad977ffa1d98@linaro.org> Date: Tue, 15 Sep 2020 13:51:48 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200915201901.GD7594@habkost.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::544; envelope-from=richard.henderson@linaro.org; helo=mail-pg1-x544.google.com X-detected-operating-system: by eggs.gnu.org: No matching host in p0f cache. That's all we know. X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , =?UTF-8?Q?Daniel_P=2e_Berrang=c3=a9?= , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 9/15/20 1:19 PM, Eduardo Habkost wrote: > Once we move to C11, we can just use max_align_t. Yes. > While we don't move to C11, why not just use > __alignof__(union { long l; void *p; double d; long double ld;}) > ? For i386, this is 4. r~