+# ifdef FREEBSD
+# define OS_TYPE "FREEBSD"
+# ifndef GC_FREEBSD_THREADS
+# define MPROTECT_VDB
+# endif
+# define SIG_SUSPEND SIGTSTP
+# define SIG_THR_RESTART SIGCONT
+# define NEED_FIND_LIMIT
+# define FREEBSD_STACKBOTTOM
+# ifdef __ELF__
+# define DYNAMIC_LOADING
+# endif
+ extern char etext[];
+ extern char * GC_FreeBSDGetDataStart();
+# define DATASTART GC_FreeBSDGetDataStart(0x1000, &etext)
+# endif