It is Sisyphean, but there also many synergies (I work on real-time computational imaging systems). And the specific things you mention were mostly not my work

It is Sisyphean, but there also many synergies (I work on real-time computational imaging systems). And the specific things you mention were mostly not my work (I made typeof in GCC more coherent, which helped getting it standardized). But yes, I have a semi-complete C compiler around and many unfinished GCC branches...