Now declarations can be deferred too, thus things like generic/template
and inline functions should be possible. However, the most important
thing is this is a step towards a cleaner middle layer for compilation,
separating front-end language from back-end code-gen.
I plan to do this eventually for Ruamoko, but I need it to keep working
for now; it's rather nice having multiple languages. I expect this will
open up a lot of options for inlining, generic/template function
instantiation, etc. Right now, it's helping with specialization
constants in glsl.
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).
Attributes seem appropriate as GLSL's qualifiers affect variables rather
than types (since there's no typedef).
Not much is done with the attributes yet other than some basic error
checking (duplicates of non-layout attributes) and debug output, but
most (if not all) declarations get to the declaration code with
attributes intact.
