In order to compile the hcode (the HexenC *.hc files) into the progs.dat
files, you need the hcc program (the hcode compiler). You can find the
sources for this utility either in hexen2source-1.5.6, or in the uhexen2
svn, on the Hammer of Thyrion downloads page.

In order to compile the original hexen2 hcode, don't use the -oi and -on
command line switches of hcc for compatibility with old saved games.  If
you use the -oi and -on optimizations, loading old saves make the engine
to emit warnings at runtime. They are actually harmless, but annoying...

$  hcc				# this compiles progs.dat
$  hcc -name progs2.src		# this compiles progs2.dat

In order to compile the mission pack, hexenworld or siege hcode, do:

$  hcc -oi -on

