Is the msvc vcbuild.bat version of Chicken the only one that relies on
CHICKEN_HOME? If so, I suggest it be depreciated for all other
installations. If we've gone to the trouble of hardwiring a bunch of
directories for csc.exe, I don't see why CHICKEN_HOME should have the
right to mess them up. Unless I'm missing something about how
CHICKEN_HOME is actually used by people. In the sources, it looks like
a hack to allow vcbuild.bat to install in a flat directory when everyone
else has a hierarchical directory structure.