FreeBSD port (36): config support

[Bruno Haible]

Roland McGrath writes:
> Is there any special reason you are using libc.so.6 as the soname?
> That seems odd for a port that isn't ABI-compatible with GNU/Linux
> (and hasn't recently had a previous libc.so.5).

I wanted to avoid clashing with FreeBSD's BSD libc, which is currently
called libc.so.4 and (as I understand it) might be called libc.so.5 in
FreeBSD 5.0.

If the soname really is irrelevant, I'll use libc.so.1. That will
avoid clashing with FreeBSD 5.0 libc as well :-)

> I think we should also have a line:
> 
> .*-.*-freebsd.*-gnu.*		DEFAULT			GLIBC_2.3
> 
> since there has never been a prior ABI for your port to be compatible with,
> right?

The oldest_abi setting that I have in
sysdeps/unix/bsd/bsd4.4/freebsd/configure.in appears to have the same
effect:

======================================================================
# Don't bother with backward compatibility with glibc versions < 2.2.6.
if test "$oldest_abi" = default; then
  oldest_abi=2.2.6
fi
======================================================================

Is anything wrong with that?

Bruno