From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-patches-return-90035-listarch-gdb-patches=sources.redhat.com@sourceware.org>
Received: (qmail 21989 invoked by alias); 18 Apr 2012 14:23:59 -0000
Received: (qmail 21966 invoked by uid 22791); 18 Apr 2012 14:23:58 -0000
X-SWARE-Spam-Status: No, hits=-7.3 required=5.0	tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,SPF_HELO_PASS,T_RP_MATCHES_RCVD
X-Spam-Check-By: sourceware.org
Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 18 Apr 2012 14:23:36 +0000
Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11])	by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q3IENEnm026414	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK);	Wed, 18 Apr 2012 10:23:14 -0400
Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1])	by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id q3IENCH3018501;	Wed, 18 Apr 2012 10:23:13 -0400
Message-ID: <4F8ECE4F.1070004@redhat.com>
Date: Wed, 18 Apr 2012 14:25:00 -0000
From: Pedro Alves <palves@redhat.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:11.0) Gecko/20120329 Thunderbird/11.0.1
MIME-Version: 1.0
To: Doug Evans <dje@google.com>
CC: Joel Brobecker <brobecker@adacore.com>,        gdb-patches <gdb-patches@sourceware.org>
Subject: Re: [RFA] Ensure result of make_cleanup is never NULL.
References: <m3bomszayu.fsf@annie.sebabeach.org> <20120416144011.GH2852@adacore.com> <4F8C3350.1030601@redhat.com> <CADPb22SfUk5s9JSSBvUTWVyhoiEqO4Gi+VNO-9MwH6rqW8qQ3g@mail.gmail.com> <CADPb22Qbp=7zsRFe=by5O3zV8VBaecYhwMjGHWA9Z_jCoTSjtQ@mail.gmail.com> <CADPb22S_CJ-in8Hw9+LPU=ZYw=0tv-VTxGC-116gJL6YsUdpqQ@mail.gmail.com> <4F8E88E3.1010900@redhat.com> <CADPb22QzKuaftpP8B-ivGqUY6iOfXU5A==sqHoM9pHs=rJqd4w@mail.gmail.com>
In-Reply-To: <CADPb22QzKuaftpP8B-ivGqUY6iOfXU5A==sqHoM9pHs=rJqd4w@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb-patches.sourceware.org>
List-Subscribe: <mailto:gdb-patches-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb-patches/>
List-Post: <mailto:gdb-patches@sourceware.org>
List-Help: <mailto:gdb-patches-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: gdb-patches-owner@sourceware.org
X-SW-Source: 2012-04/txt/msg00570.txt.bz2

On 04/18/2012 03:02 PM, Doug Evans wrote:

> On Wed, Apr 18, 2012 at 2:26 AM, Pedro Alves <palves@redhat.com> wrote:
>> On 04/18/2012 01:43 AM, Doug Evans wrote:
>>
>>> btw, I thought about making cleanup_sentinel const here, for a bit of
>>> extra robustness.
>>
>>
>> Won't that mean you'd need to cast the constness out in most, if
>> not all places that use it?


Well, aren't all places using the sentinel, using it throught the macro?
What does this make more robust?

> 
> --- cleanups.c= 2012-04-17 12:02:38.000000000 -0700
> +++ cleanups.c  2012-04-18 06:59:46.000000000 -0700
> @@ -50,10 +50,10 @@ struct cleanup
>       [though this won't catch errors that a value of, say,
>       ((struct cleanup *) -1) will]
>     - displays as something useful when printed in gdb.  */
> -static struct cleanup cleanup_sentinel;
> +static const struct cleanup cleanup_sentinel;
> 
>  /* Handy macro to use when referring to cleanup_sentinel.  */
> -#define CLEANUP_SENTINEL (&cleanup_sentinel)
> +#define CLEANUP_SENTINEL ((struct cleanup *) &cleanup_sentinel)
> 
>  /* Chain of cleanup actions established with make_cleanup,
>     to be executed if an error happens.  */



-- 
Pedro Alves