From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Denholm <nod.helm@gmail.com>
Subject: Re: [PATCH 1/9] Define a structure for object IDs.
Date: Mon, 05 May 2014 19:33:44 +1000
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References: <1399147942-165308-1-git-send-email-sandals@crustytoothpaste.net> <1399147942-165308-2-git-send-email-sandals@crustytoothpaste.net> <5365D91E.70207@alum.mit.edu> <536606AB.1020803@kdbg.org> <m2mwexke34.fsf@linux-m68k.org> <5366A09E.6030802@kdbg.org> <87ppjt6xjv.fsf@igel.home> <87lhugu7iw.fsf@fencepost.gnu.org> <87vbtk60lh.fsf@igel.home>
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Cc: Johannes Sixt <j6t@kdbg.org>,
	Michael Haggerty <mhagger@alum.mit.edu>,
	"brian m. carlson" <sandals@crustytoothpaste.net>,
	git@vger.kernel.org
To: Andreas Schwab <schwab@linux-m68k.org>, David Kastrup <dak@gnu.org>
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On 5 May 2014 19:23:06 GMT+10:00, Andreas Schwab <schwab@linux-m68k.org> wrote:
>David Kastrup <dak@gnu.org> writes:
>
>> It does not as far as I can see guarantee that a pointer to something
>> of the same type of its first member can be converted to a pointer to
>> a struct even if the struct only contains a member of such type.
>
>This sentence doesn't make any sense.  If you have an object of struct
>type then any pointer to the first member of the object can only be a
>pointer to the one and same object.

I think what David means is that a pointer to a wrapper
can be derefed into its internal, sure, but an object of
that internal type can't necessarily pretend to be a
wrapper.

That said, obviously I'm not David, so I could be wrong.
That's what I got from his statement, though.

Regards,
James Denholm.