diff --git a/test/unit/arena_mt.c b/test/unit/arena_mt.c
index ffe4c79bf8859c9328fb775c873f4ec231ac17ad..baae0941c65d72923ddee627331a49d44d1692fb 100644
--- a/test/unit/arena_mt.c
+++ b/test/unit/arena_mt.c
@@ -7,7 +7,9 @@
 #include "unit.h"
 #include <trivia/util.h>
 #include <pthread.h>
+#ifdef TARGET_OS_FREEBSD
 #include <pthread_np.h>
+#endif
 
 struct slab_arena arena;
 struct quota quota;