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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id AC588C77B75 for ; Tue, 23 May 2023 11:56:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1q1Qc0-0000Be-Cb; Tue, 23 May 2023 07:55:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q1Qbz-0000BB-0L for qemu-devel@nongnu.org; Tue, 23 May 2023 07:55:31 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1q1Qbx-0005LS-3M for qemu-devel@nongnu.org; Tue, 23 May 2023 07:55:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684842926; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=2rMaZR8SqtuOVlr8iHVn3Ks0EuuKQVnHT9L8QCSJ1i8=; b=MgXAeSsg6QLnnWkoZelsSjtRwxJGhCBwy2bt2iTNIjKXJKdmRHWRZ6QJz7UVU6UAiSXcrF JLQRHo8GFD86ADhYJirwCMZbB4vLMPOhR77Ico8reuLkfVKuGfTF1rI3WXW3xIZFmM07Yk lAMiGzoyU9ay2KlPpW/EAsDMWNY8qt4= Received: from mail-ua1-f72.google.com (mail-ua1-f72.google.com [209.85.222.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-478-uQAOUJb_PvCqB4Wm7cdrBQ-1; Tue, 23 May 2023 07:55:25 -0400 X-MC-Unique: uQAOUJb_PvCqB4Wm7cdrBQ-1 Received: by mail-ua1-f72.google.com with SMTP id a1e0cc1a2514c-773260e46e3so2350121241.0 for ; Tue, 23 May 2023 04:55:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684842925; x=1687434925; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=2rMaZR8SqtuOVlr8iHVn3Ks0EuuKQVnHT9L8QCSJ1i8=; b=ObZMY1XO/l2OJVoAf215f9Has4s+tBshOk0cm+dl6m/Qjdz//i6DcGTtYOa28wZD0b H/Twp0my32NA7UkZIgRXlgTvgegzIWXvWK0vVLiXZUQHwKMKcz1mpPnelItHCcnU+PVe f4jK2yLALZYgVYv8X7qyCpMgSUXR3msXfQQA33xG7ZTt3y1546ClGgHArOp8huT5GxGz 4vLBRhZMSjgX3QIXxrsSgxq+ldXkNlgV6IglQzLsIdXCpNgppKBFAxkOz/P8HRUYVdKC 7b+WsT3syTv392Re7jHyjqqlxVj33jRUvpjDh8mh7Pis9w3ZOtMc7yjzVoWdfWt/P/A8 h2iA== X-Gm-Message-State: AC+VfDwClqqqRKpEyo/nyT5lxC3Tj9DA2/8a/2CinWrXPY3wg+IEfsW0 rDd9LUN1OpL7YmTsHlQQly9Ef/uoVgGlmflw+Vuy7UniHEYlLrsLK6ohl7t2i9RiMmYF8u5nvIw ZRo7HAuBSi75LuLU/LjoLacK/29C1sgg= X-Received: by 2002:a67:ea8b:0:b0:439:4a00:67f0 with SMTP id f11-20020a67ea8b000000b004394a0067f0mr1569482vso.11.1684842924974; Tue, 23 May 2023 04:55:24 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ4sY+hGlgqXdv0Ir0T8Xp/36Qq5XHNro5CRPiXDX95+xc+RRpaIfdK/pXQBHV8I2kXWCln00HlnLbx1LspAk4A= X-Received: by 2002:a67:ea8b:0:b0:439:4a00:67f0 with SMTP id f11-20020a67ea8b000000b004394a0067f0mr1569480vso.11.1684842924733; Tue, 23 May 2023 04:55:24 -0700 (PDT) MIME-Version: 1.0 References: <20230522080816.66320-1-pbonzini@redhat.com> In-Reply-To: From: Paolo Bonzini Date: Tue, 23 May 2023 13:55:13 +0200 Message-ID: Subject: Re: [PATCH] meson: remove -no-pie linker flag To: =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= Cc: qemu-devel@nongnu.org, vr_qemu@t-online.de, marcandre.lureau@redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=170.10.133.124; envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-124.mimecast.com 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, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, May 23, 2023 at 10:18=E2=80=AFAM Daniel P. Berrang=C3=A9 wrote: > > The issue is that Meson only has "enable PIE" or "leave PIE to the > > compiler default", while QEMU also has "disable PIE"---which is the > > messy one. > > Does QEMU actually need "disable PIE" ? It existed in configure of > course, is there a reason we need to continue to support it in meson ? We have "disable PIE" support because PIE has a performance cost, though that's mostly for 32-bit x86 processors. Other ISAs have instructions that help (like x86-64's RIP-relative addressing, aarch64's adr/adrp, or RISC-V's auipc) and then position-independent code becomes the natural one anyway. However, I am inclined to keep it also because "--disable-pie uses the compiler default, and who knows what your distro did" is less obvious than "--disable-pie disables PIE". Paolo