Since cygwin has pushed up its libtool to 2.2.6 and Guile uses libtool 1.5.x, this mismatch can cause a compilation failure.

To work around this, you can try the following

I have attached 5 small patches configure.in.patch, Makefile.am.patch, guile.c.patch, srfi-14.c.patch and posix.c.patch.

The first three do the upgrade to libtool 2.2.6.  The last two fix totally harmless pedantic errors that could safely be ignored were it not for the -Werror.

$ tar xzvf guile-1.8.5.tar.gz
$ cd guile-1.8.5
$ cp ../Makefile.am.patch ../configure.in.patch .
$ patch < Makefile.am.patch
$ patch < configure.in.patch
$ cd libguile
$ cp ../../srfi-14.c.patch ../../posix.c.patch ../../guile.c.patch .
$ patch < srfi-14.c.patch 
$ patch < posix.c.patch
$ patch < guile.c.patch
$ cd ..
$ libtoolize
$ aclocal
$ autoconf
$ ./configure && make

The shell scripts that call the standalone tests in "make check" hang for some reason.  Also, you still get the "freeze on ^D in the REPL" bug that has been a longstanding cygwin mis-feature.

Thanks,

Mike Gran