From patchwork Fri Oct 13 08:46:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manos Pitsidianakis X-Patchwork-Id: 1848152 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=linaro.org header.i=@linaro.org header.a=rsa-sha256 header.s=google header.b=w8vYQQBj; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4S6L6c0VgWz1yqn for ; Fri, 13 Oct 2023 19:59:36 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qrDtH-0008Ss-4L; Fri, 13 Oct 2023 04:51:27 -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 1qrDst-0007PN-4r for qemu-devel@nongnu.org; Fri, 13 Oct 2023 04:51:03 -0400 Received: from mail-lf1-x131.google.com ([2a00:1450:4864:20::131]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qrDsq-0001dV-LA for qemu-devel@nongnu.org; Fri, 13 Oct 2023 04:51:02 -0400 Received: by mail-lf1-x131.google.com with SMTP id 2adb3069b0e04-50337b43ee6so2508191e87.3 for ; Fri, 13 Oct 2023 01:51:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1697187059; x=1697791859; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=uJpxflpF0VSGP1lY+JunfkK8++cYRxJyDiFsuvVgAAM=; b=w8vYQQBjvulDyD9Wdu/YHa7fOllo/b7ichbXAt2D0QySO+PEad5d1Fp3bHXmfwgIh3 a6VUl78NPecSilVTl3MHX/eWI74iBAeRqmZIk10K13HARzlHB/WEgblTfW/GVcHRdTy5 hHQSeCdULHQpJR5RahsrVHhAcT1G9yGu5uCpAjPU5AVWFKe84IuiNJVSNiNiEMgyv7C9 WeHSJJ762l9r0fmZtUd4h9QLB49i2i3OgJzEeIjthGxlEHb/apedmjJTHKf/xtKrGTV3 8OhCSBHRGnsb7ytMfymadsaID95k43VuM3JRi7oPpWmAWEygUHWJE8Mxe5u7ripj3wNW mRkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697187059; x=1697791859; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=uJpxflpF0VSGP1lY+JunfkK8++cYRxJyDiFsuvVgAAM=; b=eBRwydM4AKMCyyMd7BUKItEaLSrd0hqly29xtlBsqi3O8mIM7gld7VJiOvYtLJLdYq uLEuJ8QEnBzepl9gzj/hXdTqbJ3VIkqvuXrEqhm/1MLLB3aTW0m7h8QSQqdmq5Zk2S/n Kvx+bFqroMV2qRjVzOpm8bOpNa0vCaDNXNTbmyCfrnZRbtcQGAgN8YPvhTkCbWRxKRyZ lPVmngLtOgfChmz1Wkv+/NqDuFTY48Agcw1NVwYkdiomVo7j2Y8dYptT6M2nsKcTcBdJ yaSdFRV9plzikrjcsIsKeRn6y/FOuVh+tLLtdLAJV+sg/9/mCjG0u43MyAl7HbWA7RJy Wu4Q== X-Gm-Message-State: AOJu0Yz8eExA/2I+1/jEPtIQVZFraLkcupswrouG+1tvqLza9w5OQh9M IZHZZxQ1uPVwhQv+3a1YDfYV43xqye1VnzUttl8= X-Google-Smtp-Source: AGHT+IGYxtapLYBLjPlYkh4BbnYViUKIPYbAbm3GGy9a4KuXIUIx3/vQ3ZzNLIe4OnJim6s4w5lnOQ== X-Received: by 2002:a19:4f43:0:b0:500:a240:7240 with SMTP id a3-20020a194f43000000b00500a2407240mr21866359lfk.52.1697187058681; Fri, 13 Oct 2023 01:50:58 -0700 (PDT) Received: from localhost.localdomain (adsl-170.109.242.226.tellas.gr. [109.242.226.170]) by smtp.gmail.com with ESMTPSA id v10-20020a5d678a000000b0032d9f32b96csm569185wru.62.2023.10.13.01.50.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 Oct 2023 01:50:58 -0700 (PDT) From: Emmanouil Pitsidianakis To: qemu-devel@nongnu.org Cc: Emmanouil Pitsidianakis , =?utf-8?q?Alex?= =?utf-8?q?_Benn=C3=A9e?= , =?utf-8?q?Daniel_P=2E_Be?= =?utf-8?q?rrang=C3=A9?= , Thomas Huth , Markus Armbruster , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Juan Quintela , Paolo Bonzini , =?utf-8?q?Marc-Andr=C3=A9_Lureau?= Subject: [RFC PATCH v3 78/78] meson.build: increase -Wimplicit-fallthrough to 5 Date: Fri, 13 Oct 2023 11:46:46 +0300 Message-Id: <80a212fc419991612ca732cb3ed1c923a079ec3b.1697186560.git.manos.pitsidianakis@linaro.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=2a00:1450:4864:20::131; envelope-from=manos.pitsidianakis@linaro.org; helo=mail-lf1-x131.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 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Make GCC's implicit fall-through static analysis stricter by requiring the use of the fallthrough attribute statement instead of comments. This makes the QEMU code style more consistent. Signed-off-by: Emmanouil Pitsidianakis --- docs/devel/style.rst | 23 +++++++++++++++++++++++ meson.build | 2 +- 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/docs/devel/style.rst b/docs/devel/style.rst index 2f68b50079..f473dd24e9 100644 --- a/docs/devel/style.rst +++ b/docs/devel/style.rst @@ -634,6 +634,29 @@ are still some caveats to beware of return g_steal_pointer(&foo); } +Implicit switch case fall-through +================================= + +The C language allows switch cases to "fall-through" when a "break" statement +is missing at the end of a case. This, however, introduces ambiguity in the +code, as it's not always clear if the missing break is intentional or a bug. + +As this behaviour allows for bugs we do not allow "implicit fall-through". + +In order to identify intentional fall-through cases, we have adopted a +pseudo-keyword macro 'fallthrough' which expands to gcc's extension +__attribute__((__fallthrough__)). `Statement Attributes +`_ + +All switch/case blocks must end in one of: + +.. code-block:: c + + break; + fallthrough; + continue; + goto