[PATCH xserver] meson: Don't use '' in link_with, ever

[Jon Turney]

On 23/10/2017 21:21, Lyude Paul wrote:
> String arguments as elements in the array passed to the link_with
> argument in meson's executable() functions are not valid and will end up
> causing the build file generation to file. This actually ended up
> exposing a bug in meson that caused it not to report where in the
> meson.build file it was failing:
> 
> https://github.com/mesonbuild/meson/pull/2527
> 
> The proper way to have a variable that can contain either an empty link
> target or an actual link target is:
> 
> some_target = []
> if some_cond
>      some_target = static_library(...)
> endif
> 
> This way if some_cond is False, some_target gets set to [], gets passed
> to executable() in the link_with array, and then gets removed by array
> flattening.
> 
> This also unbreaks Xwayland builds with -Dglx=false, the thing that
> originally made me notice this.
> 
> Signed-off-by: Lyude Paul <lyude at redhat.com>
> ---
>   glx/meson.build    | 2 +-
>   hw/dmx/meson.build | 2 +-
>   meson.build        | 4 ++--
>   3 files changed, 4 insertions(+), 4 deletions(-)

Reviewed-by: Jon Turney <jon.turney at dronecode.org.uk>