From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:35811)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <sw@weilnetz.de>) id 1YUAff-000807-TO
	for qemu-devel@nongnu.org; Sat, 07 Mar 2015 04:05:21 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <sw@weilnetz.de>) id 1YUAfZ-0000X3-R5
	for qemu-devel@nongnu.org; Sat, 07 Mar 2015 04:05:19 -0500
Received: from v220110690675601.yourvserver.net ([37.221.199.173]:49071)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <sw@weilnetz.de>) id 1YUAfZ-0000WJ-L8
	for qemu-devel@nongnu.org; Sat, 07 Mar 2015 04:05:13 -0500
Message-ID: <54FABF39.4020404@weilnetz.de>
Date: Sat, 07 Mar 2015 10:04:57 +0100
From: Stefan Weil <sw@weilnetz.de>
MIME-Version: 1.0
References: <CAJSP0QWdGTKYMLcyTWjUfAYA2R964T-ESkBpnVn4F-yVx2Nv6w@mail.gmail.com>
In-Reply-To: <CAJSP0QWdGTKYMLcyTWjUfAYA2R964T-ESkBpnVn4F-yVx2Nv6w@mail.gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] clang warnings too noisy
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Stefan Hajnoczi <stefanha@gmail.com>, Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-devel <qemu-devel@nongnu.org>

Am 06.03.2015 um 20:06 schrieb Stefan Hajnoczi:
> Hi Peter,
> You are rejecting pull requests that produce warnings under clang.
>
> clang 3.5.0 on Fedora 21 produces so much noise that it's extremely
> tedious and error-prone to try finding relevant new warnings.
>
> Are you using a different clang version which produces fewer warnings?
>
> Is anyone working on making QEMU build cleanly under clang?  Under gcc
> people regularly submit patches to keep the build clean (e.g. recent
> gcc 5 fixes).
>
> Currently I'm not happy wrangling with clang when very few people seem
> to use it or care enough to make QEMU build cleanly.
>

Compilation with different compilers is still very important to detect 
hidden bugs. Here is the latest example which I found because of your 
e-mail:

block/iscsi.c:1329:20: warning: comparison of array 'iscsi_url->user' 
not equal to a null pointer is always true [-Wtautological-pointer-compare]

The code is wrong (I'll send a patch), and the code where it was copied 
from is wrong, too (see https://github.com/sahlberg/libiscsi/pull/146).

I use clang on Mac from time to time and used it some time ago on Linux.

Regards
Stefan