[PATCH] make sure compiler supports warning flags

[Artem Bityutskiy]

On Wed, 2009-02-25 at 18:38 -0500, Mike Frysinger wrote:
> Some compilers (like gcc-3.3) don't support all the newer -W flags that we
> are using.  So import the compiler check found in the kernel and test each
> flag we add.  The := is important so we only do the compiler tests once
> per `make` rather than every time we compile a file.
> 
> Signed-off-by: Mike Frysinger <vapier at gentoo.org>

Looks fine for me, but I cannot really review this, so lets wait a
little, and if there are no complaints I'll push it. Thanks!

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)