From: Arnd Bergmann <arnd@arndb.de>
To: Frantisek Hrbata <fhrbata@redhat.com>
Subject: Re: [RFC PATCH 3/4] gcov: compile specific gcov implementation based on gcc version
Date: Sun, 25 Aug 2013 20:29:45 +0200
User-Agent: KMail/1.12.2 (Linux/3.8.0-22-generic; KDE/4.3.2; x86_64; ; )
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>,
        linux-kernel@vger.kernel.org, jstancek@redhat.com,
        keescook@chromium.org, rusty@rustcorp.com.au,
        linux-arch@vger.kernel.org, mgahagan@redhat.com, agospoda@redhat.com
References: <1377247176-13537-1-git-send-email-fhrbata@redhat.com> <52177DE8.6090704@linux.vnet.ibm.com> <20130824194413.GB2365@localhost.localdomain>
In-Reply-To: <20130824194413.GB2365@localhost.localdomain>
MIME-Version: 1.0
Content-Type: Text/Plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
Message-Id: <201308252029.45375.arnd@arndb.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1397
Lines: 23

On Saturday 24 August 2013, Frantisek Hrbata wrote:
> If I understand it correctly, this would mean that you will be able to use only
> one implementation of gcov format at the time. Meaning you will be able to get
> coverage data for module, but not for kernel if it was compiled with different
> gcc(gcda format). This is probably ok if you work only on your module, but I'm
> not sure this is generally the right approach. In this case I would probably
> rather see some support for more gcov formats at the same time(e.g. set of
> callback operations per gcov version). Again I'm probably missing something, but
> I still cannot see reason why to add such feature. If you want gcov support just
> compile your kernel and modules with the same gcc version(gcda format). But if
> this is really needed maybe it would be better to consider some parallel support
> for more gcov formats based on the gcov_info version.

The kernel is always built with exactly one version, including all the modules.
I don't see any reason whatsoever to support externally built modules with gcov,
in particular when they are not built with the system compiler.

	Arnd
--
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/