multi_index/detail/define_if_constexpr_macro.hpp

0001 /* Copyright 2003-2022 Joaquin M Lopez Munoz.
0002  * Distributed under the Boost Software License, Version 1.0.
0003  * (See accompanying file LICENSE_1_0.txt or copy at
0004  * http://www.boost.org/LICENSE_1_0.txt)
0005  *
0006  * See http://www.boost.org/libs/multi_index for library home page.
0007  */
0008
0009 #if !defined(BOOST_CONFIG_HPP)
0010 #error <boost/config.hpp> must be included before this header
0011 #endif
0012
0013 #if !defined(BOOST_MULTI_INDEX_DETAIL_UNDEF_IF_CONSTEXPR_MACRO)
0014
0015 #if !defined(BOOST_NO_CXX17_IF_CONSTEXPR)
0016 #define BOOST_MULTI_INDEX_IF_CONSTEXPR if constexpr
0017 #else
0018 #define BOOST_MULTI_INDEX_IF_CONSTEXPR if
0019 #if defined(BOOST_MSVC)
0020 #define BOOST_MULTI_INDEX_DETAIL_C4127_DISABLED
0021 #pragma warning(push)
0022 #pragma warning(disable:4127) /* conditional expression is constant */
0023 #endif
0024 #endif
0025
0026 #else
0027
0028 #undef BOOST_MULTI_INDEX_IF_CONSTEXPR
0029 #if defined(BOOST_MULTI_INDEX_DETAIL_C4127_DISABLED)
0030 #pragma warning(pop)
0031 #undef BOOST_MULTI_INDEX_DETAIL_C4127_DISABLED
0032 #endif
0033
0034 #endif