Re: [Qemu-devel] [PATCH] net: add mmsghdr struct check for L2TPV3

[Peter Maydell]

On 1 July 2014 13:23,  <address@hidden> wrote:
> From: Gonglei <address@hidden>
>
> because mmsghdr struct is introduced on Linux kernel 3.3+.
> add check for mmsghdr, it only gets built on hosts that
> support mmsghdr.

> +l2tpv3="yes"
>  pixman=""
>  sdl=""
>  sdlabi="1.2"
> @@ -1712,6 +1713,21 @@ else
>  fi
>
>  ##########################################
> +# L2TPV3 probe
> +
> +if test "$l2tpv3" != "no" ; then

When can this "if" ever be false? There's no command line
to enable/disable, so you might as well just always run
the compile_prog test and set l2tpv3 to yes or no here
(and then you don't need the initialization above).

> +  cat > $TMPC << EOF
> +#include <sys/socket.h>
> +int main(void) { return sizeof(struct mmsghdr); }
> +EOF
> +  if compile_prog "" "" ; then
> +    l2tpv3=yes
> +  else
> +    l2tpv3=no
> +  fi
> +fi

thanks
-- PMM