From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sipsolutions.net (s3.sipsolutions.net [168.119.38.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EDE45315D40; Thu, 9 Apr 2026 14:47:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=168.119.38.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775746075; cv=none; b=IQq+9eoY+2gWdC5PzIDXR8wesCGZEIav5IeU41aNZwNCqAk9peH/OI3epAPwv5x1DjFgSvzQ8aYFiszbQ61xahvfHhpIZPJnORdmL9MkNGyziVKHrPBZs7/xOvS5s4LP+nUqomi8l++bKmCRYu44+VvGHWoe5ZlddkAeKTjtQRQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775746075; c=relaxed/simple; bh=4qnlhWkrVAC2M+j7AtAL9W6fLDOd3C2x6KpG3K+AnaU=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=oJt49DHoFkk3oSg2Vea6lh9GZa0Ov0tricHM5f5OlznPc5gSIrff4cNPBtl9rpu2eNbrf7s6/DbvNDXEOgKi8BuVfePUmxTpEEtPUyuNe8ECuk9gBT8OqFLDIbaw0BwtSTh3Eig1A7FgPOVDfKtQFfdZcyszarurX27tp3NNzrQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sipsolutions.net; spf=pass smtp.mailfrom=sipsolutions.net; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b=JUcDj1so; arc=none smtp.client-ip=168.119.38.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b="JUcDj1so" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=vtWvECdJsOce5KQBkQ6BB16WnHR2lmUFEE8FNue2MfA=; t=1775746064; x=1776955664; b=JUcDj1so+5PMg8X/Ilo2vk9KWS1t9Snio50ZnblPUR+nmGX i6UY3K0mCsnoJmk7ZV5ZA61txcAa2LYLCXcJUfUAZjeQT9wiEP9xQaUF759a96X5JUIg//B/mNrdx /BIQqz/zng/os+ydUbK3I/C4HYo1XRGX2EJWHphf0Y5C8opROcL4gOv+eXvADA8WCB0/u7uTE67YU otT1CYg8Lz2eoL/shg+jU/CUJ1n2PTAptU7ICAnXIJWDJJXq2BIc/F2mb3BGX9CzdoZpnCCd2l5RU yJbOC2aFice2zXKmACNCA8bPj5TrETuR78ijaQCHVTHJBKtwgURN895JYIH6iONg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.98.2) (envelope-from ) id 1wAqfN-0000000G2eD-3CNn; Thu, 09 Apr 2026 16:47:33 +0200 Message-ID: <5cf1d83227fd5a6af784f0b11fcdebf9a0bc9f94.camel@sipsolutions.net> Subject: Re: [PATCH v3] gcov: Disable GCOV_PROFILE_ALL on 32-bit UML with Clang 20/21 From: Johannes Berg To: Kees Cook , Richard Weinberger Cc: kernel test robot , Nathan Chancellor , Anton Ivanov , Peter Oberparleiter , Nick Desaulniers , Bill Wendling , Justin Stitt , llvm@lists.linux.dev, linux-um@lists.infradead.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Date: Thu, 09 Apr 2026 16:47:32 +0200 In-Reply-To: <20260409052038.make.995-kees@kernel.org> References: <20260409052038.make.995-kees@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-malware-bazaar: not-scanned Hi, Maybe the subject should say "um:" instead of "gcov:" now? (I'm assuming you want us to apply it to uml tree.) > Prevent the bad combination by disabling UML's ARCH_HAS_GCOV_PROFILE_ALL > on 32-bit when using Clang 20.x or 21.x. You say 20.x or 21.x, > + # Clang 20 & 21 miscompute __builtin_object_size() under -fprofile-arcs > + # on 32-bit, causing spurious compile-time errors in check_copy_size(). > + select ARCH_HAS_GCOV_PROFILE_ALL if !(!64BIT && CLANG_VERSION >=3D 2000= 00 && CLANG_VERSION < 220100) and I see that 22.0 doesn't even exist, and maybe that's a general pattern, but it still looks confusing? Wouldn't it be better simpler to say < 220000? At least to me that more obviously is "up to 21.x". After all, 20.0 also didn't exist, and you did >=3D200000, not >200000 or >=3D200100? johannes