From 605421f4ebe37699e63eb5551c3dbc7887093e4f Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Sun, 1 Aug 2021 09:54:36 +0900
Subject: [PATCH] gcc 10.3.0 says "__VA_OPT__ is not available until C++2a"

---
 include/ruby/internal/config.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/ruby/internal/config.h b/include/ruby/internal/config.h
index 67d7e0156f..b26e7eea25 100644
--- a/include/ruby/internal/config.h
+++ b/include/ruby/internal/config.h
@@ -126,6 +126,12 @@
 #if ! defined(HAVE_VA_ARGS_MACRO)
 # undef HAVE___VA_OPT__
 
+#elif defined(__cplusplus)
+# if __cplusplus > 201703L
+#  define HAVE___VA_OPT__
+# else
+#  undef HAVE___VA_OPT__
+# endif
 #else
 # /* Idea taken from: https://stackoverflow.com/a/48045656 */
 # define RBIMPL_TEST3(q, w, e, ...) e