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Date: Sun, 21 Mar 2010 18:11:43 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] Re: [PATCH 0/9] Virtio cleanups
Message-ID: <20100321181143.GE4174@shareable.org>
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: qemu-devel@nongnu.org, Juan Quintela <quintela@redhat.com>

Michael S. Tsirkin wrote:
> That's version 1 of my patch. Version 2 removed even need for macro
> completely by moving allocations to the caller.

The downside of moving allocations are: (1) it's one more call in the
caller, to allocate the type, (2) it needs a virtual destructor for
each type to free the object, which can clutter the code if there is
no other reason for virtual destructors.

I don't think those are necessarily bad, but they can remove from the
neatness of existing code.  Personally I favour an occasional macro
using sizeof/offsetof/container_of if the result is a natural and
sensible API to all of its callers.

-- Jamie