diff --git a/openbsd-compat/openbsd-compat.h
b/openbsd-compat/openbsd-compat.h
index 6c73e5b5..c7af0135 100644
--- a/openbsd-compat/openbsd-compat.h
+++ b/openbsd-compat/openbsd-compat.h
@@ -122,7 +122,7 @@ int getpeereid(int , uid_t *, gid_t *);
unsigned int arc4random(void);
#endif
-#if defined(HAVE_ARC4RANDOM_STIR)
+#if !defined(HAVE_ARC4RANDOM_STIR)
void arc4random_stir(void);
#elif defined(HAVE_ARC4RANDOM) || defined(LIBRESSL_VERSION_NUMBER)
/* Recent system/libressl implementation; no need for explicit stir */
