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diff --git a/src/boost/libs/hana/test/issues/github_331.cpp b/src/boost/libs/hana/test/issues/github_331.cpp
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+++ b/src/boost/libs/hana/test/issues/github_331.cpp
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+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <boost/hana/at.hpp>
+#include <boost/hana/bool.hpp>
+#include <boost/hana/first.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/pair.hpp>
+#include <boost/hana/second.hpp>
+#include <boost/hana/tuple.hpp>
+
+#include <type_traits>
+#include <utility>
+namespace hana = boost::hana;
+
+
+// In GitHub issue #331, we noticed that `first` and `second` could sometimes
+// return the wrong member in case of nested pairs. This is due to the way we
+// inherit from base classes to enable EBO. We also check for `basic_tuple`,
+// because both are implemented similarly.
+
+int main() {
+    {
+        using Nested = hana::pair<hana::int_<1>, hana::int_<2>>;
+        using Pair = hana::pair<hana::int_<0>, Nested>;
+        Pair pair{};
+
+        auto a = hana::first(pair);
+        static_assert(std::is_same<decltype(a), hana::int_<0>>{}, "");
+
+        auto b = hana::second(pair);
+        static_assert(std::is_same<decltype(b), Nested>{}, "");
+    }
+
+    {
+        using Nested = hana::basic_tuple<hana::int_<1>, hana::int_<2>>;
+        using Tuple = hana::basic_tuple<hana::int_<0>, Nested>;
+        Tuple tuple{};
+
+        auto a = hana::at_c<0>(tuple);
+        static_assert(std::is_same<decltype(a), hana::int_<0>>{}, "");
+
+        auto b = hana::at_c<1>(tuple);
+        static_assert(std::is_same<decltype(b), Nested>{}, "");
+    }
+
+    // Original test case submitted by Vittorio Romeo
+    {
+        hana::pair<hana::int_<1>, hana::bool_<false>> p{};
+        auto copy = hana::make_pair(hana::int_c<0>, p);
+        auto move = hana::make_pair(hana::int_c<0>, std::move(p));
+
+        copy = move; // copy assign
+        copy = std::move(move); // move assign
+    }
+}