And they even pass validation (though it turns out there's a bug in
glslangValidator regarding specialization constants with expressions (or
possibly spirv-val, but it seems to be the former as my bug report shows
signs of activity in that direction)).
https://github.com/KhronosGroup/glslang/issues/3748
They're currently wrong since they're meant to be for specialization
constants (and that whole system is currently broken anyway) but are
instead raw code expressions, but progress is progress.
It's nowhere near complete, but unary and binary expressions that are
marked as constant will not be subject to constant folding. This is
necessary for proper support of specialization constants.
I'm not sure I got all the checks right, but bsp_gbuf.geom passes the
validity (but failes due to not having implemented the application of
the qualifiers).
