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From: Peter Maydell <peter.maydell@linaro.org>
Date: Sun, 30 Jun 2013 16:51:26 +0100
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Subject: Re: [Qemu-devel] [RFC PATCH 0/4] per-object libraries
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To: Michael Tokarev <mjt@tls.msk.ru>
Cc: Paolo Bonzini <pbonzini@redhat.com>, Anthony Liguori <aliguori@us.ibm.com>, =?UTF-8?Q?Andreas_F=C3=A4rber?= <afaerber@suse.de>, qemu-devel@nongnu.org

On 30 June 2013 16:36, Michael Tokarev <mjt@tls.msk.ru> wrote:
> I don't understand.  I for one like to see a plugins system used in qemu,
> and except of the build system everything else is easy (and even nice,
> there's even no need to load all plugins at startup as was initially
> suggested).  But for this to work, we really need to separate libs
> used only by plugins from the main lot, -- or else there's just no
> reason to build plugins in the first place.

So, why do we want to build things as plugins? Neither of the
cover letters to your two patch series nor Anthony's wiki page
on modules actually give the rationale.

I'd like to see the reasons why we want this feature clearly laid
out, because it is a big load of extra faff and potential portability
issues (surrounding dlopen, possible use of libtool, etc), as
well as being really easy to misunderstand as some kind of promise
of API/ABI stability or third-party extension functionality.[*]

[*] by which I mean that although everybody here proposing patches
is clear that that's out of scope, end users don't generally read
patches and rationale emails, and "we dlopen device models" looks
really really like a plugin ABI...

thanks
-- PMM