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Date: Fri, 27 Jun 2008 09:58:16 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Benny Halevy <bhalevy@panasas.com>
Cc: Greg KH <greg@kroah.com>, linux-kernel@vger.kernel.org,
       Benny Halevy <bhalevy@panasas.com>
Subject: Re: [PATCH] usb: fix uninitialized variables in keyspan_pda
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On Fri, 27 Jun 2008 10:58:54 +0300
Benny Halevy <bhalevy@panasas.com> wrote:

> The compiler (gcc 4.3.0) warns that status might be used uninitialized
> in keyspan_pda_tiocmget and keyspan_pda_tiocmset.
> 
> It is technically correct and therefore this patch initializes
> status to 0 in both cases.
> 
> Note that keyspan_pda_get_modem_info sets *value only when
> usb_control_msg returns rc > 0, otherwise it must
> return an error rc < 0, and it must never return rc == 0, hence
> a WARN_ON(rc == 0) was added in case usb_control_msg ever return 0.

That seems like overkill - and by forcing status to 0 you will hide
future gcc error catches. Far better to change the two callers to test
for > 0 not >= 0 surely ?

Alan