From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hx4M8-0002IT-Or for barebox@lists.infradead.org; Mon, 12 Aug 2019 07:03:02 +0000 Date: Mon, 12 Aug 2019 09:02:59 +0200 From: Sascha Hauer Message-ID: <20190812070259.smq4wxhsxqlxdt4e@pengutronix.de> References: <20190807164808.15228-1-yamada.masahiro@socionext.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190807164808.15228-1-yamada.masahiro@socionext.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] kbuild: use -fmacro-prefix-map to make __FILE__ a relative path To: Masahiro Yamada Cc: barebox@lists.infradead.org On Thu, Aug 08, 2019 at 01:48:08AM +0900, Masahiro Yamada wrote: > Linux commit a73619a845d5625079cc1b3b820f44c899618388 > > The __FILE__ macro is used everywhere in the kernel to locate the file > printing the log message, such as WARN_ON(), etc. If the kernel is > built out of tree, this can be a long absolute path, like this: > > WARNING: CPU: 1 PID: 1 at /path/to/build/directory/arch/arm64/kernel/foo.c:... > > This is because Kbuild runs in the objtree instead of the srctree, > then __FILE__ is expanded to a file path prefixed with $(srctree)/. > > Commit 9da0763bdd82 ("kbuild: Use relative path when building in a > subdir of the source tree") improved this to some extent; $(srctree) > becomes ".." if the objtree is a child of the srctree. > > For other cases of out-of-tree build, __FILE__ is still the absolute > path. It also means the kernel image depends on where it was built. > > A brand-new option from GCC, -fmacro-prefix-map, solves this problem. > If your compiler supports it, __FILE__ is the relative path from the > srctree regardless of O= option. This provides more readable log and > more reproducible builds. > > Please note __FILE__ is always an absolute path for external modules. > > Signed-off-by: Masahiro Yamada > --- > Makefile | 3 +++ > 1 file changed, 3 insertions(+) Applied, thanks Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox