Well, my point here is that if we want to see GHC branch into other fields (mine being safety critical), and actually see the code generated by GHC be what's really running (rather than once-removed in the form of an EDSL), some changes will have to be made.
Is JHC not suitable in this case? It won't compile all of
Haskell but it does some to be doing the right things as
regards a pluggable RTS.
I think it's fair to say at this point that GHC can compile
all the Haskell we want and that new Haskell pieces will come
to GHC before anything else gets them. So going with a totally
new system, front-to-back, is not really desirable when all
you want is a new RTS; however, I don't think GHC was designed
to be a "Haskell compiler superserver".
--
Jason Dusek