With -O2:
../rootston/desktop.c: In function ‘desktop_surface_at’:
../rootston/desktop.c:714:18: error: ‘roots_output’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if ((surface = layer_surface_at(roots_output,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
&roots_output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM],
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ox, oy, sx, sy))) {
~~~~~~~~~~~~~~~
3f6823092a