From 62541cdfd05dc49b6ea7cd88bec7b4eff6c47c53 Mon Sep 17 00:00:00 2001
From: Adam Mitz <mitza@objectcomputing.com>
Date: Fri, 26 Apr 2019 12:08:15 -0500
Subject: [PATCH] Make sure mutable_variant_object's templated constructor
 doesn't get called to make a copy. Issue seen on GCC 7 -std=c++1z Fix by
 Kevin Heifner

---
 include/fc/variant_object.hpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/fc/variant_object.hpp b/include/fc/variant_object.hpp
index f27e9e70c..c07b1f10e 100644
--- a/include/fc/variant_object.hpp
+++ b/include/fc/variant_object.hpp
@@ -193,7 +193,9 @@ namespace fc
       ///@}
 
 
-      template<typename T>
+      template<typename T,
+               typename = std::enable_if_t<!std::is_base_of<mutable_variant_object,
+                                                            std::decay_t<T>>::value>>
       explicit mutable_variant_object( T&& v )
       :_key_value( new std::vector<entry>() )
       {