From eeeada1c775ba6a9a6b5519cdec9bc54c7f4ddf7 Mon Sep 17 00:00:00 2001
From: Eric Fiselier <eric@efcs.ca>
Date: Sat, 13 Jun 2015 02:18:44 +0000
Subject: [PATCH] Enable __is_trivially* intrinsics for GCC 5.1

Until GCC 5.1 the __is_trivially* intrinsics were not provided. Enable use of
the builtins for GCC 5.1.

Also enable Reference qualified member functions for GCC 4.9 and greater.

This patch also defines _GNUC_VER to 0 when __GNUC__ is not defined because
libc++ assumes _GNUC_VER is always defined.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@239653 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/__config    |  2 ++
 include/type_traits | 15 +++++++++------
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/include/__config b/include/__config
index 97c66c85..79f34e44 100644
--- a/include/__config
+++ b/include/__config
@@ -17,6 +17,8 @@
 
 #ifdef __GNUC__
 #define _GNUC_VER (__GNUC__ * 100 + __GNUC_MINOR__)
+#else
+#define _GNUC_VER 0
 #endif
 
 #if !_WIN32
diff --git a/include/type_traits b/include/type_traits
index 760047ab..20dc1568 100644
--- a/include/type_traits
+++ b/include/type_traits
@@ -1789,7 +1789,8 @@ struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const volatil
     typedef _Rp (_FnType) (_Param..., ...);
 };
 
-#if __has_feature(cxx_reference_qualified_functions)
+#if __has_feature(cxx_reference_qualified_functions) || \
+    (defined(_GNUC_VER) && _GNUC_VER >= 409)
 
 template <class _Rp, class _Class, class ..._Param>
 struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param...) &, true, false>
@@ -1919,7 +1920,7 @@ struct __member_pointer_traits_imp<_Rp (_Class::*)(_Param..., ...) const volatil
     typedef _Rp (_FnType) (_Param..., ...);
 };
 
-#endif  // __has_feature(cxx_reference_qualified_functions)
+#endif  // __has_feature(cxx_reference_qualified_functions) || _GNUC_VER >= 409
 
 #else  // _LIBCPP_HAS_NO_VARIADICS
 
@@ -2691,7 +2692,7 @@ struct _LIBCPP_TYPE_VIS_ONLY is_move_constructible
 
 #ifndef _LIBCPP_HAS_NO_VARIADICS
 
-#if __has_feature(is_trivially_constructible)
+#if __has_feature(is_trivially_constructible) || _GNUC_VER >= 501
 
 template <class _Tp, class... _Args>
 struct _LIBCPP_TYPE_VIS_ONLY is_trivially_constructible
@@ -2750,7 +2751,7 @@ struct _LIBCPP_TYPE_VIS_ONLY is_trivially_constructible
 {
 };
 
-#if __has_feature(is_trivially_constructible)
+#if __has_feature(is_trivially_constructible) || _GNUC_VER >= 501
 
 template <class _Tp>
 struct _LIBCPP_TYPE_VIS_ONLY is_trivially_constructible<_Tp, __is_construct::__nat,
@@ -2838,7 +2839,7 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_trivially_move_constructibl
 
 // is_trivially_assignable
 
-#if __has_feature(is_trivially_assignable)
+#if __has_feature(is_trivially_assignable) || _GNUC_VER >= 501
 
 template <class _Tp, class _Arg>
 struct is_trivially_assignable
@@ -3276,6 +3277,8 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_standard_layout
 template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_trivially_copyable
 #if __has_feature(is_trivially_copyable)
     : public integral_constant<bool, __is_trivially_copyable(_Tp)>
+#elif _GNUC_VER >= 501
+    : public integral_constant<bool, !is_volatile<_Tp>::value && __is_trivially_copyable(_Tp)>
 #else
     : integral_constant<bool, is_scalar<typename remove_all_extents<_Tp>::type>::value>
 #endif
@@ -3284,7 +3287,7 @@ template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_trivially_copyable
 // is_trivial;
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_trivial
-#if __has_feature(is_trivial) || (_GNUC_VER >= 407)
+#if __has_feature(is_trivial) || _GNUC_VER >= 407
     : public integral_constant<bool, __is_trivial(_Tp)>
 #else
     : integral_constant<bool, is_trivially_copyable<_Tp>::value &&