external SACargs is not yet supported.

types. These are used by the C interface to wrap/unwrap user
defined types into sacargs.

this makes it far more rebust to new node types in the fundef chain,
e.g., the funbundles introduced by sac4c

arguments in order to cater for ids in array arguments. 

by nested propergate withloops correctly.

the WL has propagate ops

the C interface

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.

without option -noprelude

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