GNU configure --options. It's not always obvious exactly what is
intended, but this merits investigation.
-=item make clean
-
-Currently, B<make clean> isn't all that useful, though
-B<make realclean> and B<make distclean> are. This needs a bit of
-thought and documentation before it gets cleaned up.
-
=item Try gcc if cc fails
Currently, we just give up.