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Date:   Wed, 23 Jan 2019 12:58:29 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     linux-kernel@vger.kernel.org,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Laura Abbott <labbott@redhat.com>,
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Subject: Re: [PATCH 1/3] treewide: Lift switch variables out of switches
Message-ID: <20190123115829.GA31385@kroah.com>
References: <20190123110349.35882-1-keescook@chromium.org>
 <20190123110349.35882-2-keescook@chromium.org>
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On Wed, Jan 23, 2019 at 03:03:47AM -0800, Kees Cook wrote:
> Variables declared in a switch statement before any case statements
> cannot be initialized, so move all instances out of the switches.
> After this, future always-initialized stack variables will work
> and not throw warnings like this:
> 
> fs/fcntl.c: In function ‘send_sigio_to_task’:
> fs/fcntl.c:738:13: warning: statement will never be executed [-Wswitch-unreachable]
>    siginfo_t si;
>              ^~

That's a pain, so this means we can't have any new variables in { }
scope except for at the top of a function?

That's going to be a hard thing to keep from happening over time, as
this is valid C :(

greg k-h