From c4777c309e70019082c0ba546ab84b9852f83f7c Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Tue, 24 Jan 2023 18:54:45 +0200
Subject: [PATCH] Avoid including <new> in core/launder.hpp when not C++17

---
 include/boost/core/launder.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/boost/core/launder.hpp b/include/boost/core/launder.hpp
index d32d5a0..850338e 100644
--- a/include/boost/core/launder.hpp
+++ b/include/boost/core/launder.hpp
@@ -17,7 +17,7 @@
 # endif
 #endif
 
-#if !defined(BOOST_CORE_HAS_BUILTIN_LAUNDER)
+#if (__cplusplus >= 201703L || (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)) && !defined(BOOST_CORE_HAS_BUILTIN_LAUNDER)
 # include <new>
 #endif
 
@@ -33,7 +33,7 @@ template<class T> T* launder( T* p )
     return __builtin_launder( p );
 }
 
-#elif defined(__cpp_lib_launder)
+#elif (__cplusplus >= 201703L || (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)) && defined(__cpp_lib_launder)
 
 template<class T> T* launder( T* p )
 {