Update to boost v1.64.0

boost/variant/polymorphic_get.hpp

@@ -3,7 +3,7 @@
 // See http://www.boost.org for updates, documentation, and revision history.
 //-----------------------------------------------------------------------------
 //
-// Copyright (c) 2013-2015 Antony Polukhin
+// Copyright (c) 2013-2017 Antony Polukhin
 //
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
@@ -113,13 +113,15 @@ public: // visitor interfaces
     template <typename U>
     pointer operator()(U& operand) const BOOST_NOEXCEPT
     {
+        typedef typename boost::remove_reference<Base>::type base_t;
         typedef boost::integral_constant<
             bool,
-            boost::mpl::or_<
-                boost::is_base_of<Base, U>,
-                boost::is_same<Base, U>,
-                boost::is_same<typename boost::remove_cv<Base>::type, U >
-            >::value
+            (
+                boost::is_base_of<base_t, U>::value &&
+                (boost::is_const<base_t>::value || !boost::is_const<U>::value)
+            )
+            || boost::is_same<base_t, U>::value
+            || boost::is_same<typename boost::remove_cv<base_t>::type, U >::value
         > tag_t;
 
         return this_type::get(operand, tag_t());

boost/variant/recursive_wrapper_fwd.hpp

@@ -4,7 +4,7 @@
 //-----------------------------------------------------------------------------
 //
 // Copyright (c) 2002 Eric Friedman, Itay Maman
-// Copyright (c) 2016 Antony Polukhin
+// Copyright (c) 2016-2017 Antony Polukhin
 //
 // Portions Copyright (C) 2002 David Abrahams
 //
@@ -20,6 +20,7 @@
 #include <boost/mpl/aux_/lambda_support.hpp>
 #include <boost/type_traits/integral_constant.hpp>
 #include <boost/type_traits/is_constructible.hpp>
+#include <boost/type_traits/is_nothrow_move_constructible.hpp>
 
 namespace boost {
 
@@ -65,6 +66,9 @@ template <class T, class U> struct is_constructible<recursive_wrapper<T>, const
 template <class T, class U> struct is_constructible<recursive_wrapper<T>, recursive_wrapper<U>& >       : boost::false_type{};
 template <class T, class U> struct is_constructible<recursive_wrapper<T>, const recursive_wrapper<U>& > : boost::false_type{};
 
+// recursive_wrapper is not nothrow move constructible, because it's constructor does dynamic memory allocation.
+// This specialisation is required to workaround GCC6 issue: https://svn.boost.org/trac/boost/ticket/12680
+template <class T> struct is_nothrow_move_constructible<recursive_wrapper<T> > : boost::false_type{};
 
 ///////////////////////////////////////////////////////////////////////////////
 // metafunction is_recursive_wrapper (modeled on code by David Abrahams)

boost/variant/variant.hpp

@@ -1756,10 +1756,12 @@ public: // structors, cont.
 
     template <typename T>
     variant(const T& operand,
-        typename boost::enable_if<mpl::and_<
-            mpl::not_< boost::is_same<T, variant> >,
-            boost::detail::variant::is_variant_constructible_from<const T&, internal_types>
-        > >::type* = 0)
+        typename boost::enable_if<mpl::or_<
+            mpl::and_<
+                mpl::not_< boost::is_same<T, variant> >,
+                boost::detail::variant::is_variant_constructible_from<const T&, internal_types>
+            >, 
+            boost::is_same<T, boost::recursive_variant_> > >::type* = 0)
     {
         convert_construct(operand, 1L);
     }
@@ -1767,11 +1769,13 @@ public: // structors, cont.
     template <typename T>
     variant(
           T& operand
-        , typename boost::enable_if<mpl::and_<
-            mpl::not_< is_const<T> >,
-            mpl::not_< boost::is_same<T, variant> >,
-            boost::detail::variant::is_variant_constructible_from<T&, internal_types>
-        > >::type* = 0
+        , typename boost::enable_if<mpl::or_<
+            mpl::and_<
+                mpl::not_< is_const<T> >,
+                mpl::not_< boost::is_same<T, variant> >,
+                boost::detail::variant::is_variant_constructible_from<T&, internal_types>
+            >,
+            boost::is_same<T, boost::recursive_variant_> > >::type* = 0
         )
     {
         convert_construct(operand, 1L);
@@ -1780,12 +1784,14 @@ public: // structors, cont.
 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
     template <class T>
     variant(T&& operand,
-        typename boost::enable_if<mpl::and_<
-            boost::is_rvalue_reference<T&&>,
-            mpl::not_< boost::is_const<T> >,
-            mpl::not_< boost::is_same<T, variant> >,
-            boost::detail::variant::is_variant_constructible_from<T&&, internal_types>
-        > >::type* = 0)
+        typename boost::enable_if<mpl::or_<
+            mpl::and_<
+                boost::is_rvalue_reference<T&&>,
+                mpl::not_< boost::is_const<T> >,
+                mpl::not_< boost::is_same<T, variant> >,
+                boost::detail::variant::is_variant_constructible_from<T&&, internal_types>
+            >,
+            boost::is_same<T, boost::recursive_variant_> > >::type* = 0)
     {
         convert_construct( detail::variant::move(operand), 1L);
     }

boost/variant/variant_fwd.hpp

@@ -59,7 +59,7 @@
     GCC before 4.0 had no variadic tempaltes; 
     GCC 4.6 has incomplete implementation of variadic templates.
 
-    MSVC2013 has variadic templates, but they have issues.
+    MSVC2015 Update 1 has variadic templates, but they have issues.
 
     NOTE: Clang compiler defines __GNUC__
 */