Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754634AbaAATdm (ORCPT ); Wed, 1 Jan 2014 14:33:42 -0500 Received: from mail-ea0-f180.google.com ([209.85.215.180]:53031 "EHLO mail-ea0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752993AbaAATdk (ORCPT ); Wed, 1 Jan 2014 14:33:40 -0500 MIME-Version: 1.0 In-Reply-To: <20140101114244.GB3372@free.fr> References: <1387481759-14535-3-git-send-email-keescook@chromium.org> <20140101114244.GB3372@free.fr> Date: Wed, 1 Jan 2014 11:33:38 -0800 X-Google-Sender-Auth: KGBsK15o7NtsiLF5RwvXiahoqF0 Message-ID: Subject: Re: [patch core/stackprotector] stackprotector: Fix build when compiler lacks support From: Linus Torvalds To: "Yann E. MORIN" Cc: Kees Cook , David Rientjes , Ingo Molnar , Peter Zijlstra , Andrew Morton , Russell King - ARM Linux , Ralf Baechle , Thomas Gleixner , "H. Peter Anvin" , LKML , Arjan van de Ven , James Hogan , Michal Marek , Paul Mundt , Shawn Guo , Stephen Rothwell , linux-kbuild , Sam Ravnborg , "linux-tip-commits@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1569 Lines: 43 On Wed, Jan 1, 2014 at 3:42 AM, Yann E. MORIN wrote: > > On 2013-12-31 16:16 -0800, Linus Torvalds spake thusly: >> >> What we really really want to do is to have some way to add config >> options based on shell scripts and compiler support. That would also >> get rid of a lot of Makefile trickery etc. >> >> Then we could just make CC_STACKPROTECTOR_STRONG depend on >> CC_SUPPORTS_STACKPROTECTOR_STRONG or whatever. > > Sam Ravnborg suggested somethink along those lines back in July: > http://marc.info/?l=linux-kbuild&m=137399785206527&w=2 > and a tentative implementation: > http://marc.info/?l=linux-kbuild&m=137409581406434&w=2 Ack. Looks good to me. I've wanted this for a long time for other reasons, we should finally just do it. That said, we should make sure that the shell execution thing gets access to $(CC) etc variables that we have in > Basically, that would give something like: > > config CC_SUPPORTS_STACKPROTECTOR_STRONG > bool > option exec="some/script/to/test-gcc -fstack-protector-strong" For the compiler options, it would hopefully be sufficient to just do something like config CC_SUPPORTS_STACKPROTECTOR_STRONG bool option exec="$CC -fstack-protector-strong -c empty.c" or something like that. No? Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/