include stdlib.h (to get at NULL)
/* -----------------------------------------------------------------------------
- $Id: Arena.c,v 1.3 2002/07/26 09:35:46 simonmar Exp $
+ $Id: Arena.c,v 1.4 2002/07/28 02:31:11 sof Exp $
(c) The University of Glasgow 2001
Arena allocation. Arenas provide fast memory allocation at the
which most allocations are small.
-------------------------------------------------------------------------- */
+#include <stdlib.h>
#include "Rts.h"
#include "RtsUtils.h"
#include "BlockAlloc.h"