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From: Tom Tromey <tromey@redhat.com>
To: Pedro Alves <palves@redhat.com>
Cc: Doug Evans <dje@google.com>, 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>	<4F8ECE4F.1070004@redhat.com>
Date: Wed, 18 Apr 2012 14:38:00 -0000
In-Reply-To: <4F8ECE4F.1070004@redhat.com> (Pedro Alves's message of "Wed, 18	Apr 2012 15:23:11 +0100")
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>>>>> "Pedro" == Pedro Alves <palves@redhat.com> writes:

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

If you initialize the object it can end up in a read-only section, so
writes to it will SEGV.

In this particular case I don't see that this would help a lot, since
the object is just a sentinel.  But, it wouldn't hurt and maybe it would
catch some really unusual bug.

Tom