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Date: Fri, 12 Aug 2016 10:01:26 +0800
From: Fam Zheng <famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4 1/9] util: Add UUID API
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To: Richard Henderson <rth@twiddle.net>
Cc: qemu-devel@nongnu.org, kwolf@redhat.com, qemu-block@nongnu.org, sw@weilnetz.de, jcody@redhat.com, mdroth@linux.vnet.ibm.com, armbru@redhat.com, pbonzini@redhat.com, mreitz@redhat.com

On Thu, 08/11 23:21, Richard Henderson wrote:
> On 08/11/2016 05:50 AM, Fam Zheng wrote:
> >+void qemu_uuid_bswap(QemuUUID *uuid)
> >+{
> >+    bswap32s((uint32_t *)&uuid->data[0]);
> >+    bswap16s((uint16_t *)&uuid->data[4]);
> >+    bswap16s((uint16_t *)&uuid->data[6]);
> >+}
> 
> You have alignment problems here too.  Perhaps you really did want
> to add uint32_t (and uint16_t?) as union members to QemuUUID.

But that may not be enough for embedded QemuUUID in a packed structure, such as
in block/vdi.c. So I'll also add an assertion here.

Fam