From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 52A571101 for ; Thu, 28 Jul 2022 10:05:28 +0000 (UTC) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id B201235312; Thu, 28 Jul 2022 10:05:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1659002719; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=I4L3qc5+151HmmRgPtNa+xmMNqlZi95xVHkUHYV5uRo=; b=aYeJGV4wYLD8CmxhgkbWsJEdn9HsfBe7MX+7DSe3AF3YRhu1L4xhBOpnvoXbdSEw5Q+NnS Vxpl33lvejau2J9C/3PSb1CXCqc8r8V2uZuTUwStWJAgi0ZA3nmsWxwaxURC8Bd4yDAOql i82QsQyq8nUZRjRUOvPUnYalr2ZQ214= Received: from suse.cz (unknown [10.100.208.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 0F63B2C142; Thu, 28 Jul 2022 10:05:18 +0000 (UTC) Date: Thu, 28 Jul 2022 12:05:18 +0200 From: Petr Mladek To: Nathan Chancellor Cc: Justin Stitt , ndesaulniers@google.com, andriy.shevchenko@linux.intel.com, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, rostedt@goodmis.org, senozhatsky@chromium.org, trix@redhat.com Subject: Re: [PATCH v4] lib/test_printf.c: fix clang -Wformat warnings Message-ID: References: <20220718230626.1029318-1-justinstitt@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed 2022-07-27 12:39:32, Nathan Chancellor wrote: > Hi Petr, > > On Tue, Jul 19, 2022 at 02:17:47PM +0200, Petr Mladek wrote: > > On Mon 2022-07-18 16:06:26, Justin Stitt wrote: > > > see warnings: > > > | lib/test_printf.c:157:52: error: format specifies type 'unsigned char' > > > | but the argument has type 'int' [-Werror,-Wformat] > > > test("0|1|1|128|255", > > > | "%hhu|%hhu|%hhu|%hhu|%hhu", 0, 1, 257, 128, -1); > > > - > > > | lib/test_printf.c:158:55: error: format specifies type 'char' but the > > > | argument has type 'int' [-Werror,-Wformat] test("0|1|1|-128|-1", > > > | "%hhd|%hhd|%hhd|%hhd|%hhd", 0, 1, 257, 128, -1); > > > - > > > | lib/test_printf.c:159:41: error: format specifies type 'unsigned > > > short' > > > | but the argument has type 'int' [-Werror,-Wformat] > > > | test("2015122420151225", "%ho%ho%#ho", 1037, 5282, -11627); > > > > > > There's an ongoing movement to eventually enable the -Wformat flag for > > > clang. Previous patches have targeted incorrect usage of > > > format specifiers. In this case, however, the "incorrect" format > > > specifiers are intrinsically part of the test cases. Hence, fixing them > > > would be misaligned with their intended purpose. My proposed fix is to > > > simply disable the warnings so that one day a clean build of the kernel > > > with clang (and -Wformat enabled) would be possible. It would also keep > > > us in the green for alot of the CI bots. > > > > > > Link: https://github.com/ClangBuiltLinux/linux/issues/378 > > > Suggested-by: Nathan Chancellor > > > Suggested-by: Nick Desaulniers > > > Signed-off-by: Justin Stitt > > > > Looks good to me: > > > > Reviewed-by: Petr Mladek > > Would you be able to take this for 5.20 or should we ask Andrew to pick > it up? It seems you two seem to split applying patches to this file and > we are trying to get -Wformat enabled for clang in 5.20. I take most vsprintf-related patches via the printk git tree last few years. Anyway, I have just committed the patch into printk/linux.git, branch for-5.20. Best Regards, Petr