I've been trying to create a couple of packages and I'm wondering
why one would use GNU_CONFIGURE vs. HAS_CONFIGURE.  I notice that the
with GNU_CONFIGURE=YES, the configure stage never does a good
config.guess, producing stuff like:  'i386--netbsdelf', while using
HAS_CONFIGURE=YES typically produces system types like:
'i386-unknown-netbsdelf1.6'... Now in practice the weak system guess
under GNU_CONFIGURE has not caused any problems for me so far, I'm just
wondering if someone can explain these two settings to me in 25 words or
less.  

Thanks!