> I poked around in the source code a bit more
> and found that AC_CYGWIN does a AC_REQUIRE([AC_CANONICAL_HOST])
> and is getting called from my configure.in.
>
> Sure enough, that seemed to be the problem.
> I made the following modification and my
> script started working again.
As AC_CYGWIN says: it is obsolete; you should be using
AC_CANONICAL_HOST and then checking $host_os to detect
Cygwin (and the same goes for Mingw32 and EMX). So
AC_CYGWIN is perfectly justified in AC_REQUIRE'ing
AC_CANONICAL_HOST, because it can then check $host_os
and set CYGWIN accordingly.
