[libcxx-commits] [libcxx] [libc++] LWG 3821 uses_allocator_construction_args should have overload for pair-like (PR #66939)

[Louis Dionne via libcxx-commits]

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@@ -139,23 +157,33 @@ template <class _Tp>
 inline constexpr bool __convertible_to_const_pair_ref =
     decltype(__uses_allocator_detail::__convertible_to_const_pair_ref_impl<_Tp>(0))::value;
 
+#  if _LIBCPP_STD_VER >= 23
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ldionne wrote:

Can you explain why we need to do something different in C++23 and before? i.e. maybe point me to the that changed in the spec between C++20 and C++23, since I couldn't see it when looking at the LWG issue.

https://github.com/llvm/llvm-project/pull/66939