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From: Daniel Micay <danielmicay@gmail.com>
Date: Sat, 10 Mar 2018 18:44:35 -0500
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Subject: Re: [PATCH] drivers: net: wireless: ath: ath9: dfs: remove VLA usage
To: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Andreas Christoforou <andreaschristofo@gmail.com>,
        Kees Cook <keescook@chromium.org>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        QCA ath9k Development <ath9k-devel@qca.qualcomm.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        linux-wireless@vger.kernel.org, Netdev <netdev@vger.kernel.org>,
        kernel list <linux-kernel@vger.kernel.org>
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> Just wondering. Is this actually a VLA. FFT_NUM_SAMPLES was static const so
> not really going to show a lot of variation. This array will always have the
> same size on the stack.

The issue is that unlike in C++, a `static const` can't be used in a
constant expression in C. It's unclear why C is defined that way but
it's how it is and there isn't currently a GCC extension making more
things into constant expressions like C++.