hugs w/ cygwin

FYI, hugs builds cleanly with two cygwin installs I've tested on here: an older one w/ gcc-2.95 and one w/ gcc-3.2 (from a clean cygwin install done on 29/07/03). The reported behaviour suggests a C compiler making life too hard for the conservative GC; one way to find out is to cut back on the use of -O2. Re: Registry gibberish -- this was due to unhygienic macro usage in opts.c. Fixed now. --sigbjorn