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=-14.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 25E55C4360C for ; Thu, 26 Sep 2019 16:24:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E53B921D56 for ; Thu, 26 Sep 2019 16:24:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="V1V+3mtP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727485AbfIZQY5 (ORCPT ); Thu, 26 Sep 2019 12:24:57 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:36720 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727426AbfIZQY4 (ORCPT ); Thu, 26 Sep 2019 12:24:56 -0400 Received: by mail-wm1-f68.google.com with SMTP id m18so3264766wmc.1 for ; Thu, 26 Sep 2019 09:24:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2nru33jX5uOHTAnOwLDnlw05X11ddri3AYOGkrr2Jgw=; b=V1V+3mtP4Mr4m1w6tfMRbEe9Ot6If7Ve01XI2YG4LZeIr9POGflhogI5MiaFDd+OTC gb8KPbGdy7b/A35QAk4fvXuCzB/GnS3FL9lkD0hlAe6PEzNZx4SpDwynLfg7+NPHmlMt ZN7IRg8XP3Ln2EO9I4oLGYs6OjlH2hDIxZEZZD8f3COYXFxmpjYDstW5vNK3G8sJA2X9 ARQ5J8yGrbqaxrI8A5HmRdJDuZqX3dAfsuPBC0V+ws5m5a2ph9pO41VUHFAAv9H/gY3a qVbYreAXZVhNLlQUp2UGxcrvyxqemO0mWdozn0/WEv/124DO4O2TNRv+Rcpr5cYfPZVU EWlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2nru33jX5uOHTAnOwLDnlw05X11ddri3AYOGkrr2Jgw=; b=R5mNG5ufPERp+/QHXjNbbQjaZeBDITYLdObuRPO22HTyuLpBeRkUxOsUcD8p9ws/IO fkhhEUPCc4HBaxmGnSo2uOOkY6lpbzYKumlBv6OSLc5zCQCK41h1AYFL3f1+s7wadw9p /SNWiG+0JyUUhQg5eHQKMvfg5ezgXAYiFwQMnVddt0352+cE23eCXXKCmFWuD6h9dC+6 oRT4f6WsE93IJ1Yjb9crzFn3d2JafviSwf1iQ4S+XmDzaBFyI7pae4txTFxgXtdEite+ Pc6Fj6Nw9COPqggm+YXni7q4McGwak93dgn+pc2rVWsuMGJ8p8G4FbT1YPKu2lPs3q2a wbRA== X-Gm-Message-State: APjAAAVMWbfU5uOZQ+6KtXVo0uhQQVc8j3sZvpO2Rm9FwmkQyrJ1SBK9 f+YEeF8M43KRGNsqhtthCNg= X-Google-Smtp-Source: APXvYqwaeWWyc+5+I6rQCqh8o9AxGdr9DXIEJ1q4zyd710j8awNFMljewcJbtzhvMqUo+yVe/31u8Q== X-Received: by 2002:a1c:a404:: with SMTP id n4mr3688226wme.41.1569515094418; Thu, 26 Sep 2019 09:24:54 -0700 (PDT) Received: from localhost.localdomain ([2a01:4f8:222:2f1b::2]) by smtp.gmail.com with ESMTPSA id t6sm5820701wmf.8.2019.09.26.09.24.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Sep 2019 09:24:53 -0700 (PDT) From: Nathan Chancellor To: Steven Rostedt , Ingo Molnar Cc: linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, David Bolvansky , Nathan Chancellor , Nick Desaulniers Subject: [PATCH v2] tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro Date: Thu, 26 Sep 2019 09:22:59 -0700 Message-Id: <20190926162258.466321-1-natechancellor@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190925172915.576755-1-natechancellor@gmail.com> References: <20190925172915.576755-1-natechancellor@gmail.com> MIME-Version: 1.0 X-Patchwork-Bot: notify Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After r372664 in clang, the IF_ASSIGN macro causes a couple hundred warnings along the lines of: kernel/trace/trace_output.c:1331:2: warning: converting the enum constant to a boolean [-Wint-in-bool-context] kernel/trace/trace.h:409:3: note: expanded from macro 'trace_assign_type' IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, ^ kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN' WARN_ON(id && (entry)->type != id); \ ^ 264 warnings generated. This warning can catch issues with constructs like: if (state == A || B) where the developer really meant: if (state == A || state == B) This is currently the only occurrence of the warning in the kernel tree across defconfig, allyesconfig, allmodconfig for arm32, arm64, and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix the warnings and find potential issues in the future. Link: https://github.com/llvm/llvm-project/commit/28b38c277a2941e9e891b2db30652cfd962f070b Link: https://github.com/ClangBuiltLinux/linux/issues/686 Reviewed-by: Nick Desaulniers Signed-off-by: Nathan Chancellor --- v1 -> v2: * Update commit message to give context behind the warning and explain this is currently the only occurrence of this warning in the tree. * Add Nick's Reviewed-by tag. kernel/trace/trace.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 26b0a08f3c7d..f801d154ff6a 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -365,11 +365,11 @@ static inline struct trace_array *top_trace_array(void) __builtin_types_compatible_p(typeof(var), type *) #undef IF_ASSIGN -#define IF_ASSIGN(var, entry, etype, id) \ - if (FTRACE_CMP_TYPE(var, etype)) { \ - var = (typeof(var))(entry); \ - WARN_ON(id && (entry)->type != id); \ - break; \ +#define IF_ASSIGN(var, entry, etype, id) \ + if (FTRACE_CMP_TYPE(var, etype)) { \ + var = (typeof(var))(entry); \ + WARN_ON(id != 0 && (entry)->type != id); \ + break; \ } /* Will cause compile errors if type is not found. */ -- 2.23.0