diff --git a/src/lj_arch.h b/src/lj_arch.h
index fe55815736..c8d7138e0e 100644
--- a/src/lj_arch.h
+++ b/src/lj_arch.h
@@ -74,7 +74,7 @@
        defined(__NetBSD__) || defined(__OpenBSD__) || \
        defined(__DragonFly__)) && !defined(__ORBIS__)
 #define LUAJIT_OS	LUAJIT_OS_BSD
-#elif (defined(__sun__) && defined(__svr4__))
+#elif (defined(__sun__) && defined(__svr4__)) || defined(__HAIKU__)
 #define LUAJIT_OS	LUAJIT_OS_POSIX
 #elif defined(__CYGWIN__)
 #define LJ_TARGET_CYGWIN	1