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Date: Tue, 19 May 2009 21:31:00 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [PATCH] fix qemu_malloc() error check for size==0
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To: malc <av1474@comtv.ru>, Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org

Eduardo Habkost wrote:
> I really hope you are not proposing to make qemu_realloc(p, 0) work but
> qemu_malloc(0) fail, because you would be breaking lots of
> realloc()/malloc() equivalency assumptions.

Careful.

realloc(p, 0) *always* frees p (or does nothing if p == NULL), on all
systems complying with ISO C, and always returns NULL.

malloc(0) on the other hand does not guarantee this,
so malloc(0) is *not* a substitute for realloc(NULL, 0).

-- Jamie