From 59780ba08eac8112c1e0906afff9c122a74b648b Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Sat, 11 Sep 2021 18:00:29 +0300
Subject: [PATCH] Only assert when C++14

---
 include/boost/variant2/variant.hpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/boost/variant2/variant.hpp b/include/boost/variant2/variant.hpp
index debd0bf..2aeb7b2 100644
--- a/include/boost/variant2/variant.hpp
+++ b/include/boost/variant2/variant.hpp
@@ -371,8 +371,12 @@ template<std::size_t I, class... T> constexpr variant_alternative_t<I, variant<T
 {
     static_assert( I < sizeof...(T), "Index out of bounds" );
 
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
     BOOST_ASSERT( v.index() == I );
 
+#endif
+
     return v._get_impl( mp11::mp_size_t<I>() );
 }
 
@@ -380,8 +384,12 @@ template<std::size_t I, class... T> constexpr variant_alternative_t<I, variant<T
 {
     static_assert( I < sizeof...(T), "Index out of bounds" );
 
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
     BOOST_ASSERT( v.index() == I );
 
+#endif
+
     return std::move( v._get_impl( mp11::mp_size_t<I>() ) );
 }
 
@@ -389,8 +397,12 @@ template<std::size_t I, class... T> constexpr variant_alternative_t<I, variant<T
 {
     static_assert( I < sizeof...(T), "Index out of bounds" );
 
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
     BOOST_ASSERT( v.index() == I );
 
+#endif
+
     return v._get_impl( mp11::mp_size_t<I>() );
 }
 
@@ -398,8 +410,12 @@ template<std::size_t I, class... T> constexpr variant_alternative_t<I, variant<T
 {
     static_assert( I < sizeof...(T), "Index out of bounds" );
 
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
     BOOST_ASSERT( v.index() == I );
 
+#endif
+
     return std::move( v._get_impl( mp11::mp_size_t<I>() ) );
 }