From d6b970285b80efab57cfd5451f6c942518580435 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ion=20Gazta=C3=B1aga?= <igaztanaga@gmail.com>
Date: Mon, 15 Apr 2024 08:56:32 +0200
Subject: [PATCH 1/2] Add launcer helper

---
 include/boost/move/detail/launder.hpp    | 53 ++++++++++++++++++++++++
 include/boost/move/detail/workaround.hpp |  7 +++-
 2 files changed, 59 insertions(+), 1 deletion(-)
 create mode 100644 include/boost/move/detail/launder.hpp

diff --git a/include/boost/move/detail/launder.hpp b/include/boost/move/detail/launder.hpp
new file mode 100644
index 0000000..a6236de
--- /dev/null
+++ b/include/boost/move/detail/launder.hpp
@@ -0,0 +1,53 @@
+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2014-2015. Distributed under the Boost
+// Software License, Version 1.0. (See accompanying file
+// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/container for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+#ifndef BOOST_MOVE_DETAIL_LAUNDER_HPP
+#define BOOST_MOVE_DETAIL_LAUNDER_HPP
+
+#ifndef BOOST_CONFIG_HPP
+#  include <boost/config.hpp>
+#endif
+
+#if defined(BOOST_HAS_PRAGMA_ONCE)
+#  pragma once
+#endif
+
+#include <boost/move/detail/workaround.hpp>
+
+namespace boost {
+namespace move_detail {
+
+#if defined(BOOST_MOVE_HAS_BUILTIN_LAUNDER)
+
+template<class T>
+BOOST_MOVE_FORCEINLINE T* launder(T* p)
+{
+    return __builtin_launder( p );
+}
+
+#else
+
+template<class T>
+BOOST_MOVE_FORCEINLINE T* launder(T* p)
+{
+    return p;
+}
+
+#endif
+
+template<class T>
+BOOST_MOVE_FORCEINLINE T launder_cast(const volatile void* p)
+{
+   return (launder)((T)p);
+}
+
+}  //namespace move_detail {
+}  //namespace boost {
+
+#endif   //#ifndef BOOST_MOVE_DETAIL_LAUNDER_HPP
diff --git a/include/boost/move/detail/workaround.hpp b/include/boost/move/detail/workaround.hpp
index 5edfcee..f12e933 100644
--- a/include/boost/move/detail/workaround.hpp
+++ b/include/boost/move/detail/workaround.hpp
@@ -147,5 +147,10 @@ template<unsigned> struct static_assert_test {};
 #define BOOST_MOVE_INTRINSIC_CAST BOOST_MOVE_FORCEINLINE
 #endif
 
-#endif   //#ifndef BOOST_MOVE_DETAIL_WORKAROUND_HPP
+#if defined(__has_builtin)
+#if __has_builtin(__builtin_launder)
+   #define BOOST_MOVE_HAS_BUILTIN_LAUNDER
+#endif
+#endif
 
+#endif   //#ifndef BOOST_MOVE_DETAIL_WORKAROUND_HPP

From d0631eec745828207cf251232cef0d681cb758d8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ion=20Gazta=C3=B1aga?= <igaztanaga@gmail.com>
Date: Tue, 16 Apr 2024 14:42:42 +0200
Subject: [PATCH 2/2] Implement aligned_struct with __declspec(align(x)) for x
 = 8 as MSVC will not align the stack if a built-in type is used (like
 double).

---
 include/boost/move/detail/type_traits.hpp | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/boost/move/detail/type_traits.hpp b/include/boost/move/detail/type_traits.hpp
index 84dcbce..de8b2eb 100644
--- a/include/boost/move/detail/type_traits.hpp
+++ b/include/boost/move/detail/type_traits.hpp
@@ -1197,12 +1197,20 @@ struct aligned_struct;
 template <> struct aligned_struct<1> { char data; };
 template <> struct aligned_struct<2> { short data; };
 template <> struct aligned_struct<4> { int data; };
-template <> struct aligned_struct<8> { double data; };
+//8 byte alignment does not propely work in x86 if attribute is not used.
+//If a user declares a variable with 8 byte alignment, such as a double
+//the compiler will not realign the stack.
+// 
+//If _declspec(align) is used MSVC will realign the stack.
+//
+//Disabled specialization
+//template <> struct aligned_struct<8> { double data; };
 
 #define BOOST_MOVE_ALIGNED_STRUCT(x) \
   template <> struct aligned_struct<x> { \
     __declspec(align(x)) char data; \
   }
+BOOST_MOVE_ALIGNED_STRUCT(8);
 BOOST_MOVE_ALIGNED_STRUCT(16);
 BOOST_MOVE_ALIGNED_STRUCT(32);
 BOOST_MOVE_ALIGNED_STRUCT(64);