From 03bff14498de17523a4348d1c9dce05d40a13d07 Mon Sep 17 00:00:00 2001
From: jzmaddock <jzmaddock@gmail.com>
Date: Sun, 27 Apr 2014 16:51:19 +0100
Subject: [PATCH] Updated fix for
 https://svn.boost.org/trac/boost/ticket/9910#comment:2 C++11 version of
 is_convertible does not need a check for is_abstract.

---
 include/boost/type_traits/is_convertible.hpp | 7 +++++--
 test/is_convertible_test.cpp                 | 6 ++++--
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/include/boost/type_traits/is_convertible.hpp b/include/boost/type_traits/is_convertible.hpp
index 1f083a7..a844cec 100644
--- a/include/boost/type_traits/is_convertible.hpp
+++ b/include/boost/type_traits/is_convertible.hpp
@@ -56,7 +56,9 @@ namespace detail {
 
 #if !defined(BOOST_NO_SFINAE_EXPR) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 
-   // This is a C++11 conforming version:
+   // This is a C++11 conforming version, place this first and use it wherever possible:
+
+#  define BOOST_TT_CXX11_IS_CONVERTIBLE
 
    template <class A, class B, class C>
    struct or_helper
@@ -416,7 +418,8 @@ struct is_convertible_impl_dispatch_base
    typedef is_convertible_impl_select< 
       ::boost::is_arithmetic<From>::value, 
       ::boost::is_arithmetic<To>::value,
-#ifndef BOOST_NO_IS_ABSTRACT
+#if !defined(BOOST_NO_IS_ABSTRACT) && !defined(BOOST_TT_CXX11_IS_CONVERTIBLE)
+      // We need to filter out abstract types, only if we don't have a strictly conforming C++11 version:
       ::boost::is_abstract<To>::value
 #else
       false
diff --git a/test/is_convertible_test.cpp b/test/is_convertible_test.cpp
index 9bcc3e0..3872e99 100644
--- a/test/is_convertible_test.cpp
+++ b/test/is_convertible_test.cpp
@@ -56,7 +56,7 @@ struct bug_5271b
 
 #endif
 
-#if ((!defined(BOOST_NO_SFINAE_EXPR) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)) || defined(BOOST_IS_CONVERTIBLE)) && !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
+#if (defined(BOOST_TT_CXX11_IS_CONVERTIBLE) || defined(BOOST_IS_CONVERTIBLE)) && !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
 struct bug9910
 {
    bug9910() = default;
@@ -206,11 +206,13 @@ BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible<int, bug_5271a>::value), fal
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible<int, bug_5271b>::value), true);
 #endif
 
-#if ((!defined(BOOST_NO_SFINAE_EXPR) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)) || defined(BOOST_IS_CONVERTIBLE)) && !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
+#if (defined(BOOST_TT_CXX11_IS_CONVERTIBLE) || defined(BOOST_IS_CONVERTIBLE)) && !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
 #ifndef _MSC_VER
 // MSVC gives the wrong answer here, see https://connect.microsoft.com/VisualStudio/feedback/details/858956/std-is-convertible-returns-incorrect-value
 BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible<Ref_bug9910, bug9910>::value), false);
 #endif
+// From https://svn.boost.org/trac/boost/ticket/9910#comment:2:
+BOOST_CHECK_INTEGRAL_CONSTANT((::tt::is_convertible<int, incomplete_type[]>::value), false);
 #endif
 
 TT_TEST_END