From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: [RFC][PATCH v2 1/1] Add IOREQ_TYPE_VMWARE_PORT
Date: Fri, 3 Oct 2014 10:51:52 +0100
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To: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>, Keir Fraser <keir@xen.org>, Jan Beulich <jbeulich@suse.com>, Don Slutz <dslutz@verizon.com>, xen-devel@lists.xen.org
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On Fri, 2014-10-03 at 10:47 +0100, Stefano Stabellini wrote:
> The issue with a union is compatibility with older QEMU versions: we can
> introduce the union and retain compatibility only if we use anonymous
> unions.  However I seem to recall Jan arguing against anonymous unions
> in public interfaces in past.

The canonical headers in xen/include/public are supposed to be strict
ANSI C and anonymous unions are a gcc extension.

However no-one is obliged to use this copy and several projects
(including Linux, *BSD and others) take copies and modify them to suite
their local coding styles/conventions etc. That could include using
anonymous unions if that is preferable. I'm not sure if that helps you
here though (since the issue AIUI is with existing qemu releases...)

Ian.