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Date: Wed, 20 May 2009 10:00:57 +0200
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [PATCH] Make qemu_alloc()/qemu_realloc() return NULL for size==0
	(was Re: [Qemu-devel] [PATCH] fix qemu_malloc() error check
	for	size==0)
References: <1242678676-19439-1-git-send-email-ehabkost@redhat.com>	<Pine.LNX.4.64.0905190148200.3344@linmac.oyster.ru>	<20090518221705.GO2079@blackpad>	<Pine.LNX.4.64.0905190410290.3632@linmac.oyster.ru>	<8763fxvbfk.fsf@pike.pond.sub.org>	<Pine.LNX.4.64.0905191635360.2165@linmac.oyster.ru>	<20090519140201.GB4254@blackpad>	<Pine.LNX.4.64.0905191830460.4014@linmac.oyster.ru>	<20090519144424.GD4254@blackpad>	<Pine.LNX.4.64.0905191852030.4108@linmac.oyster.ru>	<20090519164440.GH4254@blackpad>
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To: malc <av1474@comtv.ru>
Cc: qemu-devel@nongnu.org, Eduardo Habkost <ehabkost@redhat.com>, Markus Armbruster <armbru@redhat.com>

malc schrieb:
> Thanks for an attempt, but i don't like it either, since it sortof
> breaks the (unspoken?) qemu_malloc/realloc contract that those will
> never return NULL. I've commited the thing i had in mind.

I don't know of such a contract. If you want to have it, you should add
a comment which specifies what is guaranteed and what not. And best post
the patch to the list first this time.

Btw, even with your patch realloc(ptr, 0) with ptr != NULL still can
return NULL. And if you now go ahead and forbid size = 0 entirely, I'm
almost sure we have a regression as I didn't do the original patch to
allow this just for fun but because it's used...

Kevin