diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 41a42cf2..36d67b0f 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -2949,6 +2949,11 @@ options_postprocess_mutate_invariant(struct options *options)
 static void
 options_postprocess_verify(const struct options *o)
 {
+#ifdef LIBRESSL_VERSION_NUMBER
+    msg(M_WARN, "WARNING: This OpenVPN was built against LibreSSL. "
+        "This might work, but is *not* supported and can break at any time.")
+#endif
+
     if (o->connection_list)
     {
         int i;