When libwacom is configured disabled, this error appears:
../clutter/clutter/x11/clutter-input-device-xi2.c: In function ‘clutter_input_device_xi2_finalize’:
../clutter/clutter/x11/clutter-input-device-xi2.c:122:7: error: ‘device_xi2’ undeclared (first use in this function)
if (device_xi2->inhibit_pointer_query_timer)
Fix it with the "obvious" solution.
This code was added in c1303bd642e57d53ccbc8f6eb450c2a45bf4d3ef.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/611