[libcxx-commits] [libcxx] [libc++] Implement LWG3990 for Clang (PR #128834)

[Nikolas Klauser via libcxx-commits]

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@@ -37,7 +37,7 @@
 "`LWG3973 <https://wg21.link/LWG3973>`__","Monadic operations should be ADL-proof","2023-11 (Kona)","","",""
 "`LWG3974 <https://wg21.link/LWG3974>`__","``mdspan::operator[]`` should not copy ``OtherIndexTypes``","2023-11 (Kona)","","",""
 "`LWG3987 <https://wg21.link/LWG3987>`__","Including ``<flat_foo>`` doesn't provide ``std::begin``/``end``","2023-11 (Kona)","","",""
-"`LWG3990 <https://wg21.link/LWG3990>`__","Program-defined specializations of ``std::tuple`` and ``std::variant`` can't be properly supported","2023-11 (Kona)","","",""
+"`LWG3990 <https://wg21.link/LWG3990>`__","Program-defined specializations of ``std::tuple`` and ``std::variant`` can't be properly supported","2023-11 (Kona)","|Partial|","21","Implemented for Clang only."
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philnik777 wrote:

Since it's IFNDR I don't think it makes sense to track this for Clang/GCC separately. We can only improve the QoI with Clang here at the moment and it's possible we will never be able to improve anything with GCC.

https://github.com/llvm/llvm-project/pull/128834