diff --git a/include/boost/memory_order.hpp b/include/boost/memory_order.hpp
index ba7d1cd..f3268e7 100644
--- a/include/boost/memory_order.hpp
+++ b/include/boost/memory_order.hpp
@@ -3,7 +3,7 @@
 //  Defines enum boost::memory_order per the C++0x working draft
 //
 //  Copyright (c) 2008, 2009 Peter Dimov
-//  Copyright (c) 2018 Andrey Semashev
+//  Copyright (c) 2018, 2025 Andrey Semashev
 //
 //  Distributed under the Boost Software License, Version 1.0.
 //  See accompanying file LICENSE_1_0.txt or copy at
@@ -15,7 +15,7 @@
 #include <boost/config.hpp>
 
 #if defined(BOOST_HAS_PRAGMA_ONCE)
-# pragma once
+#pragma once
 #endif
 
 namespace boost
@@ -42,8 +42,6 @@ namespace boost
 // efficiently in compare_exchange methods.
 //
 
-#if !defined(BOOST_NO_CXX11_SCOPED_ENUMS)
-
 enum class memory_order : unsigned int
 {
     relaxed = 0,
@@ -54,28 +52,12 @@ enum class memory_order : unsigned int
     seq_cst = 14 // acq_rel | 8
 };
 
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_relaxed = memory_order::relaxed;
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_consume = memory_order::consume;
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_acquire = memory_order::acquire;
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_release = memory_order::release;
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_acq_rel = memory_order::acq_rel;
-BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST memory_order memory_order_seq_cst = memory_order::seq_cst;
-
-#undef BOOST_MEMORY_ORDER_INLINE_VARIABLE
-
-#else // !defined(BOOST_NO_CXX11_SCOPED_ENUMS)
-
-enum memory_order
-{
-    memory_order_relaxed = 0,
-    memory_order_consume = 1,
-    memory_order_acquire = 2,
-    memory_order_release = 4,
-    memory_order_acq_rel = 6, // acquire | release
-    memory_order_seq_cst = 14 // acq_rel | 8
-};
-
-#endif // !defined(BOOST_NO_CXX11_SCOPED_ENUMS)
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_relaxed = memory_order::relaxed;
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_consume = memory_order::consume;
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_acquire = memory_order::acquire;
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_release = memory_order::release;
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_acq_rel = memory_order::acq_rel;
+BOOST_INLINE_VARIABLE constexpr memory_order memory_order_seq_cst = memory_order::seq_cst;
 
 } // namespace boost