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From: Markus Armbruster <armbru@redhat.com>
References: <1453219845-30939-1-git-send-email-eblake@redhat.com>
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Date: Wed, 20 Jan 2016 20:03:17 +0100
In-Reply-To: <1453219845-30939-19-git-send-email-eblake@redhat.com> (Eric
	Blake's message of "Tue, 19 Jan 2016 09:10:26 -0700")
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Subject: Re: [Qemu-devel] [PATCH v9 18/37] qapi: Drop unused error argument
	for list and implicit struct
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To: Eric Blake <eblake@redhat.com>
Cc: Michael Roth <mdroth@linux.vnet.ibm.com>, Alexander Graf <agraf@suse.de>, qemu-devel@nongnu.org, "open list:sPAPR" <qemu-ppc@nongnu.org>, marcandre.lureau@redhat.com, David Gibson <david@gibson.dropbear.id.au>

Eric Blake <eblake@redhat.com> writes:

> No backend was setting an error when ending the visit of a list
> or implicit struct.

That's a lie: qmp_input_end_list() does.  But it shouldn't, as you
explain below.  Rephrase the commit message?

>                      Make the callers a bit easier to follow by
> making this a part of the contract, and removing the errp
> argument - callers can then unconditionally end an object as
> part of cleanup without having to think about whether a second
> error is dominated by a first, because there is no second error.
>
> The only addition of &error_abort in this patch, in the function
> qmp_input_end_list(), will never trigger unless a programming
> bug creates a push(struct)/pop(list) or push(list)/pop(struct)
> mismatch.
>
> A later patch will then tackle the larger task of splitting
> visit_end_struct(), which can indeed set an error (and that
> cleanup will also have the side-effect of removing the use of
> error_abort added here).
>
> Signed-off-by: Eric Blake <eblake@redhat.com>
> Reviewed-by: Marc-Andr=C3=A9 Lureau <marcandre.lureau@redhat.com>

Patch looks good.  I like the simplification.