the WL has propagate ops

the C interface

Removed all reminders to efence.

see how this impacts compiler performance, as all object files are
compiled twice now. As the C compiler usually is not the bottleneck, we
should be fine.

fixed a bug when compiling void functions

layout of modules. To use this new compiler, you need a matching stdlib,
i.e., revision 1042 or newer.

wrapping/unwrapping/typechecks and defines the SACarg type.

without option -noprelude

code can not lead to further optimization potential.
Furthermore, I added STAT_WHY which prints why a function is
reoptimized.

which is needed when compiling prelude itself (whas automagically
before) and handy when debugging small programs.