Thanks for working on this. A couple comments:
Currently, with gcl, sys-proclaim.lisp is made in one format
by "make sys-proclaim.lisp" and then overwritten in another
format by "make". I think you can just remove the line
$(EXECUTEGCL) '(progn $(LOADDEFSYSTEM) (compiler::emit-fn t) $(DEFSYSTEMCOMPILE) $(LOADMAKEPROCLAIM) (compiler::make-all-proclaims "*/*.fn" "*/*/*/*.fn"))' && \
from the $(BINARY_DIR)/maxima target.
It would be nice if all automatically generated files disappeared
with "make clean".
Dan