On Mon, Mar 19, 2018 at 2:43 AM, David Laight [off-list ref] wrote:

Is it necessary to have the full checks for old versions of gcc?

Even -Wvla could be predicated on very recent gcc - since we aren't
worried about whether gcc decides to generate a vla, but whether
the source requests one.

You are correct. We could just ignore the issue with old gcc versions,
and disable -Wvla rather than worry about it.

                  Linus