From d29bb4b7c4b97e7255856666f70f10dbeeb26beb Mon Sep 17 00:00:00 2001
From: Marshall Clow <mclow.lists@gmail.com>
Date: Mon, 8 Jul 2013 20:05:31 +0000
Subject: [PATCH] Implement n3545 for c++14

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185856 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/type_traits                                     | 4 ++++
 test/utilities/meta/meta.hel/integral_constant.pass.cpp | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/include/type_traits b/include/type_traits
index 450b5928..dd84abf2 100644
--- a/include/type_traits
+++ b/include/type_traits
@@ -236,6 +236,10 @@ struct _LIBCPP_TYPE_VIS integral_constant
     typedef integral_constant type;
     _LIBCPP_INLINE_VISIBILITY
         _LIBCPP_CONSTEXPR operator value_type() const {return value;}
+#if _LIBCPP_STD_VER > 11
+    _LIBCPP_INLINE_VISIBILITY
+         constexpr value_type operator ()() const {return value;}
+#endif
 };
 
 template <class _Tp, _Tp __v>
diff --git a/test/utilities/meta/meta.hel/integral_constant.pass.cpp b/test/utilities/meta/meta.hel/integral_constant.pass.cpp
index 7f9e2769..92d13c55 100644
--- a/test/utilities/meta/meta.hel/integral_constant.pass.cpp
+++ b/test/utilities/meta/meta.hel/integral_constant.pass.cpp
@@ -26,6 +26,11 @@ int main()
     assert(_5() == 5);
 #endif
 
+#if _LIBCPP_STD_VER > 11
+	static_assert ( _5{}() == 5, "" );
+	static_assert ( std::true_type{}(), "" );
+#endif
+
     static_assert(std::false_type::value == false, "");
     static_assert((std::is_same<std::false_type::value_type, bool>::value), "");
     static_assert((std::is_same<std::false_type::type, std::false_type>::value), "");