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 ABBF1C4332F for ; Fri, 10 Nov 2023 11:29:20 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r1PgR-0003JY-1m; Fri, 10 Nov 2023 06:28:19 -0500 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 1r1PgL-0003Io-2E for qemu-devel@nongnu.org; Fri, 10 Nov 2023 06:28:14 -0500 Received: from mail-lj1-x22c.google.com ([2a00:1450:4864:20::22c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1r1PgH-00066r-5r for qemu-devel@nongnu.org; Fri, 10 Nov 2023 06:28:12 -0500 Received: by mail-lj1-x22c.google.com with SMTP id 38308e7fff4ca-2c509f2c46cso26265931fa.1 for ; Fri, 10 Nov 2023 03:28:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1699615684; x=1700220484; darn=nongnu.org; h=content-transfer-encoding:mime-version:message-id:in-reply-to :references:user-agent:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to; bh=x2cJf8U8zq+7Qc886E7RORcVF/kML0kHxdy9k4APJtU=; b=lVBjluGrZXpb6ZIladq35o4iVt0n7YXmJnNcOpJp+2rvMpABEri9gY6qawKFTEI6Ya ylwKm8nGjZJnjww90KwOn85W9doAFghVfr/BAhuzyBaXUqsyBlgaG+zOLe/1dIFPhn5v 9SxFUWgye0mN6GMBheqpZOs2kM2lzCOIrpZrPqsbOqvIr2ixtqhdnA4tyn//DEtsxVVv tfppk6RycTJ1AeNukvgciFOho8BPKTZl7kO8tAcX27cj0RMg0OoEL5ljty7dhjuY7QZX wao85Ck6EaWmwceI9kA4NPp2GjZw++hon+MRlWfypvtkqRkCiFPRtLghcNRozYR1Awua w4mg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699615684; x=1700220484; h=content-transfer-encoding:mime-version:message-id:in-reply-to :references:user-agent:subject:cc:to:from:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=x2cJf8U8zq+7Qc886E7RORcVF/kML0kHxdy9k4APJtU=; b=F0le31Mn7emZfIwiILZ9Lm6ocbjHSEd0orSEJMQ5RvGVZa6VGiwzUvnjVhOIzSYZnI bHo1ykr9Ma4C+fZbx6ugofAbIdQ+2g2abk7kmgeJQ7KqjvEfRlMyUppTUgtY7MMhLYvX m2mN36DErvf2ts1wKp1wvoCVyVs6t5hHmiZfpcwVfp4o/HrleVmju3anRyBEPiORcvot wpox6DEEBrmXRxE8EDjISA6MdUqm+toQSfojc+lz1ABQxWqMyfapJTivzS7GoOTtUlG3 nIo96G3bw/sNvAUaNjpdTruKFSa29HsmLVAjLxcWfgO+zRQwfHuNydhsemFgXEHCZwbT oM5Q== X-Gm-Message-State: AOJu0Yxyi8sLxQjUleywMtaMFLdt61kVWl4V944wRkIUcye0KRA7Ufyg Z00RUY/WFQP24MIQobJglzEXZg== X-Google-Smtp-Source: AGHT+IEiFxW3X7KRfu9WIpr3bMT8fcKpdAkVBcwny1Vh6H3hpRmcwL8h8kl8KY6lpzxxTr01XRTVxw== X-Received: by 2002:a05:651c:a0f:b0:2c8:3571:b08c with SMTP id k15-20020a05651c0a0f00b002c83571b08cmr384477ljq.53.1699615684521; Fri, 10 Nov 2023 03:28:04 -0800 (PST) Received: from meli.delivery (adsl-109.37.6.163.tellas.gr. [37.6.163.109]) by smtp.gmail.com with ESMTPSA id u8-20020a05600c138800b004075d5664basm4975761wmf.8.2023.11.10.03.28.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Nov 2023 03:28:04 -0800 (PST) Date: Fri, 10 Nov 2023 13:25:56 +0200 From: Manos Pitsidianakis To: "Daniel P. Berrang=?UTF-8?B?w6k=?= " Cc: Peter Maydell , qemu-devel@nongnu.org, Paolo Bonzini , Gerd Hoffmann , Marc-Andr=?UTF-8?B?w6kg?=Lureau , qemu-arm@nongnu.org Subject: Re: [PATCH 2/2] Add warn_unused_result attr to AUD_register_card User-Agent: meli 0.8.2 References: <4b040fc18cb0e563e92ce084ca18b89a050a8aaa.1699606819.git.manos.pitsidianakis@linaro.org> <3wmne.fhuf28sb5yfg@linaro.org> In-Reply-To: Message-ID: <3wnuq.xckj65oye27@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=utf-8; format=flowed Received-SPF: pass client-ip=2a00:1450:4864:20::22c; envelope-from=manos.pitsidianakis@linaro.org; helo=mail-lj1-x22c.google.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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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 Fri, 10 Nov 2023 13:20, "Daniel P. Berrangé" wrote: >Your approach to the problem: > > if (!AUD_register_card("OMAP EAC", &s->codec.card, &error_fatal)) { > exit(1); > } > >is adding dead-code because the exit(1) will never be reachable. So while >it lets you squelch the unused result warning, it is verbose and misleading >to anyone who sees it. > >Perhaps a more viable option is to pull in gnulib's ignore_value macro > > #define ignore_value(x) \ > (__extension__ ({ __typeof__ (x) __x = (x); (void) __x; })) > >and then we would have just this: > > ignore_value(AUD_register_card("OMAP EAC", &s->codec.card, &error_fatal)); Good suggestion, thanks! And to be fair, I did put a comment directly above that line to explain the unreachable code path. :) + /* + * We pass error_fatal so on error QEMU will exit(). But we check the + * return value to make the warn_unused_result compiler warning go away. + */