Minor BSD fixes for Hugs Aug03

[Ross Paterson]

On Wed, Aug 27, 2003 at 11:21:26AM +0200, Volker Stolz wrote:
> The first patch to prelude.h avoids loads of gratuitious warnings about
> using malloc.h (which is deprecated).

Thanks -- I've applied a variant of this.

> The second patch to configure.in caters for FreeBSDs different pthread-flags.
> (Perhaps it's better to let the user supply the correct CFLAGS for threads?)

I don't know much about this, but on a quick look around it seems that
this situation is a real mess.  I've changed configure.in to use the
ACX_PTHREAD macro (from the GNU Autoconf Macro Archive).  I see it prefers
-kthread on FreeBSD, and hope that's OK.  It is also ignorant of -lc_r.
In any case, you can override it by setting PTHREAD_LIBS or PTHREAD_CFLAGS
in the environment of configure.

I've updated the tarball.