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Date: Mon, 30 Nov 2009 16:01:19 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] Permit zero-sized qemu_malloc() & friends
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To: Markus Armbruster <armbru@redhat.com>
Cc: qemu-devel@nongnu.org

On 11/30/2009 03:55 PM, Markus Armbruster wrote:
> Commit a7d27b53 made zero-sized allocations a fatal error, deviating
> from ISO C's malloc()&  friends.  Revert that, but take care never to
> return a null pointer, like malloc()&  friends may do (it's
> implementation defined), because that's another source of bugs.
>
> Rationale: while zero-sized allocations might occasionally be a sign of
> something going wrong, they can also be perfectly legitimate.  The
> change broke such legitimate uses.  We've found and "fixed" at least one
> of them already (commit eb0b64f7, also reverted by this patch), and
> another one just popped up: the change broke qcow2 images with virtual
> disk size zero, i.e. images that don't hold real data but only VM state
> of snapshots.
>    

I strongly agree with this patch.  A consistent API improves quality, 
especially when it is also consistent with people's expectations.

-- 
error compiling committee.c: too many arguments to function