Merge branch 'develop' into feature/max-align

include/boost/core/alignof.hpp

@@ -0,0 +1,57 @@
+#ifndef BOOST_CORE_MAX_ALIGN_HPP_INCLUDED
+#define BOOST_CORE_MAX_ALIGN_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//  Copyright 2023 Peter Dimov
+//  Distributed under the Boost Software License, Version 1.0.
+//  https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <cstddef>
+
+#if !defined(BOOST_NO_CXX11_ALIGNOF)
+
+#define BOOST_CORE_ALIGNOF alignof
+
+#elif defined(__GNUC__)
+
+#define BOOST_CORE_ALIGNOF __alignof__
+
+#elif defined(_MSC_VER)
+
+#define BOOST_CORE_ALIGNOF __alignof
+
+#else
+
+namespace boost
+{
+namespace core
+{
+namespace detail
+{
+
+template<class T> struct alignof_helper
+{
+    char x;
+    T t;
+};
+
+} // namespace detail
+} // namespace core
+} // namespace boost
+
+#if defined(__GNUC__)
+// ignoring -Wvariadic-macros with #pragma doesn't work under GCC
+# pragma GCC system_header
+#endif
+
+#define BOOST_CORE_ALIGNOF(...) offsetof( ::boost::core::detail::alignof_helper<__VA_ARGS__>, t );
+
+#endif
+
+#endif  // #ifndef BOOST_CORE_MAX_ALIGN_HPP_INCLUDED