From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fout-b1-smtp.messagingengine.com (fout-b1-smtp.messagingengine.com [202.12.124.144]) (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 8B562BA45 for ; Sun, 8 Jun 2025 08:32:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.12.124.144 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749371532; cv=none; b=lggXsqoJidCiljxOrUxjExUPzcp6qPk9zdjRNZaX7puNIr7AoR7kLl6u2F2IRajGlqixj9CVvzGP9+cHIfs+S6z91oJWC1qqBFVodCzrGV4CFWllYoW6mXZ3uxO0GfHHLxNszB/vF/OU27NNBZLhAIwxDaKerjcO5JxsG9CGS6M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749371532; c=relaxed/simple; bh=I3KsMDwr5qvkZ4rDykXuWvFT+KsLZrNF+UPrBdhe35g=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=GPL4tWn4imwP631dqDmgeJnnfJ+bVuAKrDaIj4b5vTtDLiidzt3sC5oeDPUN3s4A9de64VbbNKOr/yT/p4OYEzKXbC80UkOzbqiaWIHaGzCVyg7ak6L+NyzXA9h4BIP6D/7+5UQ78wks6y3R8FYCDGLZnpb7UQXOglyUjpOi4Oc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org; spf=none smtp.mailfrom=linux-m68k.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=m3hsCSS/; arc=none smtp.client-ip=202.12.124.144 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux-m68k.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="m3hsCSS/" Received: from phl-compute-02.internal (phl-compute-02.phl.internal [10.202.2.42]) by mailfout.stl.internal (Postfix) with ESMTP id 6C08B11400AC; Sun, 8 Jun 2025 04:32:08 -0400 (EDT) Received: from phl-mailfrontend-02 ([10.202.2.163]) by phl-compute-02.internal (MEProxy); Sun, 08 Jun 2025 04:32:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t= 1749371528; x=1749457928; bh=mZgu0Rm94Z01tFsvuUU3DItJrThYzWjRwqJ DNhTfGCc=; b=m3hsCSS/I1/rfvttRsMmxQIcA1bTYr+sFUhmhOhD8DKwFkHpZwT 3d621oVGwDq9+lbfU0RkTd+izF11/GQIp7eGrBOnzF7lMWQD5w/rrbZgFTpomZdJ LWTh21iq4cwbfZqStSmF2iYn8zMLwajEudbK01JNRsLhxghu+8lbIPYnoJtIjEN5 9JS+Jz8kRDvchr9k+1bTw1ww7dP3MSXSiNkvzFl9Q0NP/UIpfBUYfmJTzRXrRrzF kqJ3hq/WgVs5bTy2sDfrm4AfbSgMX6TOQoxlu6ujVPsYS6usWqMiwuiovO5KvwI7 QuoW89onxOwqxLoZpVXj0QTlcYgjAk1oxVg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddugdejieduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdggtfgfnhhsuhgsshgtrhhisggvpdfu rfetoffkrfgpnffqhgenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnh htshculddquddttddmnecujfgurhepfffhvfevufgjkfhfgggtsehttdertddttddvnecu hfhrohhmpefhihhnnhcuvfhhrghinhcuoehfthhhrghinheslhhinhhugidqmheikehkrd horhhgqeenucggtffrrghtthgvrhhnpeefieehjedvtefgiedtudethfekieelhfevhefg vddtkeekvdekhefftdekvedvueenucffohhmrghinhepkhgvrhhnvghlrdhorhhgnecuve hluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepfhhthhgrihhn sehlihhnuhigqdhmieekkhdrohhrghdpnhgspghrtghpthhtohephedpmhhouggvpehsmh htphhouhhtpdhrtghpthhtohepghgvrhhgsehlihhnuhigqdhmieekkhdrohhrghdprhgt phhtthhopegurghnihgvlhestdigtdhfrdgtohhmpdhrtghpthhtohepghgvvghrtheslh hinhhugidqmheikehkrdhorhhgpdhrtghpthhtoheplhhinhhugidqmheikehksehlihhs thhsrdhlihhnuhigqdhmieekkhdrohhrghdprhgtphhtthhopehlihhnuhigqdhkvghrnh gvlhesvhhgvghrrdhkvghrnhgvlhdrohhrgh X-ME-Proxy: Feedback-ID: i58a146ae:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sun, 8 Jun 2025 04:32:04 -0400 (EDT) Date: Sun, 8 Jun 2025 18:32:52 +1000 (AEST) From: Finn Thain To: Greg Ungerer cc: Daniel Palmer , geert@linux-m68k.org, linux-m68k@lists.linux-m68k.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] m68k: Enable dead code elimination In-Reply-To: <42674c5a-42fe-4846-bf90-340310393fea@linux-m68k.org> Message-ID: <5bc4ad99-3432-c7e1-32a7-e9f9db86f94a@linux-m68k.org> References: <20250416114240.2929832-1-daniel@0x0f.com> <42674c5a-42fe-4846-bf90-340310393fea@linux-m68k.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii On Tue, 29 Apr 2025, Greg Ungerer wrote: > On 29/4/25 10:04, Daniel Palmer wrote: > > > > On Mon, 28 Apr 2025 at 08:37, Greg Ungerer wrote: > >> I notice that some other architectures (arm and powerpc) have version > >> checks on gcc or ld in the config. Do you know if there is any > >> version limitations for m68k here? > > > > I'm not sure about that. I'll try to work out why they have the checks > > and see if that affects m68k too. I'm using GCC13 so probably new > > enough that most things work. > > FWIW, the oldest toolchain I had lying around was based on gcc 8.3.0 and > binutils 2.32. This patch worked fine on that. > I was going to try the patch with gcc-6.4.0 but apparently that's too old to build stock linux-6.15 (see below). Documentation/admin-guide/README.rst says I should have "at least gcc 5.1". Anyway, I think this patch should not cause any unpleasant surprises, given that "make oldconfig" says dead code elimination is EXPERIMENTAL. CC mm/vmscan.o In file included from :0:0: mm/vmscan.c: In function 'read_ctrl_pos': ././include/linux/compiler_types.h:557:38: error: call to '__compiletime_assert_469' declared with attribute error: min(tier, 4U - 1) signedness error _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ ././include/linux/compiler_types.h:538:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ ././include/linux/compiler_types.h:557:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ ./include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ ./include/linux/minmax.h:93:2: note: in expansion of macro 'BUILD_BUG_ON_MSG' BUILD_BUG_ON_MSG(!__types_ok(ux, uy), \ ^~~~~~~~~~~~~~~~ ./include/linux/minmax.h:98:2: note: in expansion of macro '__careful_cmp_once' __careful_cmp_once(op, x, y, __UNIQUE_ID(x_), __UNIQUE_ID(y_)) ^~~~~~~~~~~~~~~~~~ ./include/linux/minmax.h:105:19: note: in expansion of macro '__careful_cmp' #define min(x, y) __careful_cmp(min, x, y) ^~~~~~~~~~~~~ mm/vmscan.c:3166:37: note: in expansion of macro 'min' for (i = tier % MAX_NR_TIERS; i <= min(tier, MAX_NR_TIERS - 1); i++) { ^~~ make[4]: *** [scripts/Makefile.build:203: mm/vmscan.o] Error 1 make[3]: *** [scripts/Makefile.build:461: mm] Error 2 make[2]: *** [Makefile:2003: .] Error 2 make[1]: *** [/home/fthain/src/kernel.org/linux/Makefile:369: __build_one_by_one] Error 2