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Date: Mon, 11 Oct 2010 18:07:41 +0200
From: Stefan Weil <weil@mail.berlios.de>
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Subject: Re: [Qemu-devel] [PATCH 03/12] eepro100: initialize a variable in
	all	cases
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To: Markus Armbruster <armbru@redhat.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, qemu-devel <qemu-devel@nongnu.org>

Am 11.10.2010 16:53, schrieb Markus Armbruster:
> Blue Swirl <blauwirbel@gmail.com> writes:
>
>> Compiling with GCC 4.6.0 20100925 produced warnings:
>> /src/qemu/hw/eepro100.c: In function 'eepro100_read4':
>> /src/qemu/hw/eepro100.c:1351:14: error: 'val' may be used
>> uninitialized in this function [-Werror=uninitialized]
>> /src/qemu/hw/eepro100.c: In function 'eepro100_read2':
>> /src/qemu/hw/eepro100.c:1328:14: error: 'val' may be used
>> uninitialized in this function [-Werror=uninitialized]
>> /src/qemu/hw/eepro100.c: In function 'eepro100_read1':
>> /src/qemu/hw/eepro100.c:1285:13: error: 'val' may be used
>> uninitialized in this function [-Werror=uninitialized]
>>
>> Fix by initializing 'val' at start.
>
> I don't like sweeping bugs under the carpet like that. The initial
> value is used when and only when the emulation is buggy. We doubt it
> can happen. If we truly believe it can't happen, assert it. If we just
> doubt it, log it.

Markus, that patch would only be an intermediate solution
which helps to fix a certain class of compiler warnings.

I already promised to test the code with assertions
and started doing so (see my qemu repository
http://repo.or.cz/w/qemu/ar7.git/history/HEAD:/hw/eepro100.c).
Testing takes some time, so the intermediate solution
can be reasonable.

But nothing will be swept under the carpet!