Re: [Qemu-devel] [PATCH] configure: Fix build for some versions of glibc (9pfs)

[Serge Hallyn <serge.hallyn@canonical.com>]

Quoting Stefano Stabellini (stefano.stabellini@eu.citrix.com):
> On Thu, 7 Jun 2012, Stefan Weil wrote:
> > Some versions declare open_by_handle_at, but don't define AT_EMPTY_PATH.
> > Extend the check in configure to test both preconditions.
> > 
> > Signed-off-by: Stefan Weil <sw@weilnetz.de>
> 
> It works for me. Also I think it is a better fix than the original
> patch.

Well, it works in that it allows compilation to proceed.  It results
in ./libhw64/9pfs/virtio-9p-handle.o not being built, since AT_EMPTY_PATH
can't be found through /usr/include/fcntl.h, even though it can in
/usr/include/linux/fcntl.h.  I guess that is, unfortunately, the right
thing to do.

Oh hey, I think I've found the bug in the debian package causing
that problem.  Grr.

> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Acked-by: Serge Hallyn <serge.hallyn@ubuntu.com>

thanks,
-serge

> 
> >  configure |    4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/configure b/configure
> > index 799ad0f..f737f6c 100755
> > --- a/configure
> > +++ b/configure
> > @@ -2816,7 +2816,11 @@ fi
> >  open_by_hande_at=no
> >  cat > $TMPC << EOF
> >  #include <fcntl.h>
> > +#if !defined(AT_EMPTY_PATH)
> > +# error missing definition
> > +#else
> >  int main(void) { struct file_handle fh; return open_by_handle_at(0, &fh, 0); }
> > +#endif
> >  EOF
> >  if compile_prog "" "" ; then
> >      open_by_handle_at=yes
> > -- 
> > 1.7.10
> >