diff --git a/libstdc++-v3/include/bits/stl_pair.h b/libstdc++-v3/include/bits/stl_pair.h index acd0c7b58f9..b81b479ad43 100644 --- a/libstdc++-v3/include/bits/stl_pair.h +++ b/libstdc++-v3/include/bits/stl_pair.h @@ -404,6 +404,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION return false; } + template + static constexpr bool + _S_const_assignable() + { + if constexpr (is_assignable_v) + return is_assignable_v; + return false; + } + template static constexpr bool _S_nothrow_assignable() @@ -468,8 +477,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION /// Copy assignment operator (const) constexpr const pair& operator=(const pair& __p) const - requires is_copy_assignable_v - && is_copy_assignable_v + requires (_S_const_assignable()) { first = __p.first; second = __p.second; @@ -479,8 +487,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION /// Move assignment operator (const) constexpr const pair& operator=(pair&& __p) const - requires is_assignable_v - && is_assignable_v + requires (_S_const_assignable()) { first = std::forward(__p.first); second = std::forward(__p.second); @@ -491,8 +498,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template constexpr const pair& operator=(const pair<_U1, _U2>& __p) const - requires is_assignable_v - && is_assignable_v + requires (_S_const_assignable()) { first = __p.first; second = __p.second; @@ -503,8 +509,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template constexpr const pair& operator=(pair<_U1, _U2>&& __p) const - requires is_assignable_v - && is_assignable_v + requires (_S_const_assignable<_U1, _U2>()) { first = std::forward<_U1>(__p.first); second = std::forward<_U2>(__p.second);