[Mesa-dev] [PATCH v2] st: require compatible driver in autotools

[Emil Velikov]

On Wed, 24 Apr 2019 at 13:09, Emil Velikov <emil.l.velikov at gmail.com> wrote:
>
> On Tue, 23 Apr 2019 at 23:10, Alyssa Ross <hi at alyssa.is> wrote:
> >
> > > Off the top of my head - none of the VL code should be build when we
> > > have only a swrast driver.
> > > Can you try and kill that bug, or shall I?
> >
> > Isn't that what this patch does?
> >
> > If there's only swrast, this patch prevents enabling any of the state
> > trackers, so need_gallium_vl won't be set, and VL won't be built.
>
> How about instead of tracking each driver and combination do somethings like:
>
> if no_gallium_drivers or gallium_drivers=swrast; then
>  all_vl_state_trackers=off
>
Having a closer look such code exists already at [1]

if test -n "$with_gallium_drivers" -a "x$with_gallium_drivers" != xswrast; then
    if test "x$enable_xvmc" = xauto -a "x$have_xvmc_platform" = xyes; then
        PKG_CHECK_EXISTS([xvmc >= $XVMC_REQUIRED], [enable_xvmc=yes],
[enable_xvmc=no])
    fi
...
fi

Thus auto-detection will disable xvmc and other VL state-trackers,
when no gallium drivers or swrast only is set.
Thus the NEED_GALLIUM_VL_WINSYS shortly afterwords is set to
no/disabled, and vl_winsys_dri.c et al is not build.

A random old checkout commit 7be26976b8e8bc34fa7d55550014197ed2af488f
seems happy with the following:

mkdir aa; cd aa;
../autogen.sh      --enable-autotools \
     --with-platforms=x11 \
     --with-dri-drivers= \
     --with-gallium-drivers=swrast \
     --disable-glx \
     --disable-dri3 \
     --disable-gbm

Am I missing something?
-Emil

[1] https://cgit.freedesktop.org/mesa/mesa/tree/configure.ac?h=19.0&id=d41acb4c9e46306e3e9cebe9c23de77c6f26ff93#n2322