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From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 3 Sep 2018 13:24:16 +0100
Message-ID: <CAFEAcA8HATZQqawAX3=OPmas6uzp0UAciK7QXo=uuRbCfvUjaQ@mail.gmail.com>
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Subject: Re: [Qemu-devel] [RFC 1/6] Add bpf support to qemu
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To: =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= <berrange@redhat.com>
Cc: Sameeh Jubran <sameeh@daynix.com>, Yan Vugenfirer <yan@daynix.com>, Jason Wang <jasowang@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>

On 3 September 2018 at 12:59, Daniel P. Berrang=C3=A9 <berrange@redhat.com>=
 wrote:

>>  ##########################################
>> +# check for usable bpf system call
>> +if test "$bpf" =3D "yes"; then
>
> if test "x$bpf" !=3D "xno"; then

We don't use the leading-x thingy elsewhere in configure,
why is this condition special?
(We can assume we don't have a broken shell, and we
know that $bpf won't be a string starting with a hyphen.)

thanks
-- PMM