[libcxx-commits] [libcxx] [libcxx] implement LWG4148: unique_ptr::operator* should not allow dangling references (PR #128213)

[A. Jiang via libcxx-commits]

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@@ -261,7 +261,10 @@ class _LIBCPP_UNIQUE_PTR_TRIVIAL_ABI _LIBCPP_TEMPLATE_VIS unique_ptr {
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 __add_lvalue_reference_t<_Tp> operator*() const
-      _NOEXCEPT_(_NOEXCEPT_(*std::declval<pointer>())) {
+      _NOEXCEPT_(_NOEXCEPT_(*std::declval<pointer>()))
+    // TODO: use reference_converts_from_temporary_v once implemented.
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frederick-vs-ja wrote:

But `reference_converts_from_temporary_v` shouldn't be available before C++23. If you decide to add the `static_assert` in old modes, it may be more consistent (and less verbose) to solely use the intrinsic.

https://github.com/llvm/llvm-project/pull/128213