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Date: Thu, 15 Dec 2011 13:37:13 +0300
Message-ID: <CAMo8BfJMeVOCdM+iH4-ZYNMXDamyqeYjTzs8h-ZdPBWDBA-qgA@mail.gmail.com>
From: Max Filippov <jcmvbkbc@gmail.com>
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Subject: Re: [Qemu-devel] some questions about g_malloc in qemu
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To: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Zhi Hui Li <zhihuili@linux.vnet.ibm.com>, =?UTF-8?B?6Zmz6Z+L5Lu7?= <chenwj@iis.sinica.edu.tw>, Stefan Hajnoczi <stefanha@gmail.com>, QEMU-devel <qemu-devel@nongnu.org>, zhihuili@cn.ibm.com

>> >> =A0I found this in HACKING:
>> >>
>> >> =A0 Please note that NULL check for the g_malloc result is redundant =
and
>> >> =A0 that g_malloc() call with zero size is not allowed.
>> >
>> > So we have:
>> >
>> > 1. You should not request 0 bytes from g_malloc().
>>
>> I think this was related to qemu_malloc() and Anthony's sed run made it
>> refer to g_malloc(), even though it works just fine with 0 bytes. We
>> should probably remove this sentence.
>
> If you remove it then you can't interpret it the way I did. =A0It's not
> longer possible to say that g_malloc() never returns NULL. =A0You always
> have to qualify that with "unless you ask for 0 bytes". :)

I have a number of ELFs that result in ELF loader making zero-size malloc.
Previously I had to enable CONFIG_ZERO_MALLOC, now it just works.

--=20
Thanks.
-- Max