bug#16451: build newest guile on FreeBSD error

[Mark H Weaver <mhw@netris.org>]

z_axis <z_axis@163.com> writes:

> hi,friends
> After `git clone git://git.sv.gnu.org/guile.git`, `./autogen` reports:
> m4: illegal option -- -
> usage: m4 [-d flags] [-t name] [-gs] [-D name[=value]]...
>        [-U name]... [-I dirname]... file...
>
> on my FreeBSD 9.1 box.

Following up on this: it turns out that the call to "m4 --version" in
autogen.sh is apparently the only problem here.

I suggested (on IRC) that he run "autoreconf -i --force --verbose" (the
only important thing in autogen.sh) and it seems to have worked properly
and created a working configure script.

Some other notes on FreeBSD, while the knowledge is fresh: On FreeBSD,
the "boehm-gc" package is compiled without threading support.  To
support threads, the "boehm-gc-threaded" package is needed, which
installs the library with a nonstandard name -lgc-threaded, so
BDW_GC_LIBS="-L/usr/local/lib -lgc-threaded" must be passed to
configure.

Maybe some of this should go into a README, but first I should ask:
z_axis: did these steps produce a working Guile on FreeBSD 9.1?

    Thanks,
      Mark