diff --git a/newlib/libc/stdlib/arc4random.c b/newlib/libc/stdlib/arc4random.c
index 146e1762c..0eeaa2ccd 100644
--- a/newlib/libc/stdlib/arc4random.c
+++ b/newlib/libc/stdlib/arc4random.c
@@ -194,20 +194,17 @@ arc4random_buf(void *buf, size_t n)
 	_ARC4_UNLOCK();
 }
 
+#ifdef __CYGWIN__
+/* Exported functions removed from OpenBSD in the meantime.  Keep them,
+   but make them non-functional.  They don't return a value anyway. */
 void
 arc4random_stir(void)
 {
-        _ARC4_LOCK();
-	_rs_stir();
-	_ARC4_UNLOCK();
 }
 
 void
 arc4random_addrandom(u_char *dat, int datlen)
 {
-	_ARC4_LOCK();
-	if (!rs)
-		_rs_stir();
-	_rs_rekey(dat, datlen);
-	_ARC4_UNLOCK();
 }
+
+#endif /* __CYGWIN__ */