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From: Markus Armbruster <armbru@redhat.com>
References: <20171002152552.27999-1-armbru@redhat.com>
	<20171002152552.27999-16-armbru@redhat.com>
	<CAJ+F1CKSuJ2Zk6B4baESAdmM6RNeGFszJ1H41ZWxg+dXEcW7zQ@mail.gmail.com>
Date: Thu, 05 Oct 2017 06:29:39 +0200
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	(=?utf-8?Q?=22Marc-Andr=C3=A9?= Lureau"'s message of "Wed, 4 Oct 2017
	14:02:54 +0200")
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Subject: Re: [Qemu-devel] [RFC PATCH 15/32] tests/qapi-schema: Improve
 simple union coverage
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To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@gmail.com>
Cc: QEMU <qemu-devel@nongnu.org>, Michael Roth <mdroth@linux.vnet.ibm.com>

Marc-Andr=C3=A9 Lureau <marcandre.lureau@gmail.com> writes:

> On Mon, Oct 2, 2017 at 5:25 PM, Markus Armbruster <armbru@redhat.com> wro=
te:
>> This demonstrates a bug in the lowering of simple unions: if more than
>> one schema uses the same built-in type T for a simple union member,
>> they all generate the same q_obj_T_wrapper into their qapi-types.h.
>> They clash when you include more than one schema's qapi-types.h.
>
> Ah, I don't remember seeing that when I splitted the schema in my
> qapi-if / conditional series.

Simple union members of built-in type are rare.  I spotted the problem
with options, then realized it's already possible with simple unions.

> Could it happen with non-built-in types ?

Yes, but multiple q_obj_T_wrapper can clash only when their T also
clash.  Name your types more wisely then.

>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>
> Reviewed-by: Marc-Andr=C3=A9 Lureau <marcandre.lureau@redhat.com>

Thanks!