From fc40fbb93f0291861c7f78bb0eec0df3bdd94ff7 Mon Sep 17 00:00:00 2001
From: Sebastian Ullrich <sebasti@nullri.ch>
Date: Thu, 21 Mar 2019 17:45:49 +0100
Subject: [PATCH] chore(util/rb_tree): suppress warning from suppressing
 unknown warning

---
 src/util/rb_tree.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/util/rb_tree.h b/src/util/rb_tree.h
index bc380d583d..36d335213f 100644
--- a/src/util/rb_tree.h
+++ b/src/util/rb_tree.h
@@ -5,7 +5,9 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Author: Leonardo de Moura
 */
 #pragma once
+#if !defined(__has_warning) || __has_warning("-Wreturn-std-move")
 #pragma clang diagnostic ignored "-Wreturn-std-move"
+#endif
 #include <utility>
 #include <algorithm>
 #include "runtime/optional.h"