[libcxx-commits] [libcxx] [libcxx] improves diagnostics for containers with bad value types (PR #106296)

[Christopher Di Bella via libcxx-commits]

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@@ -1024,6 +1029,15 @@ template <class _Key,
           class _Pred  = equal_to<_Key>,
           class _Alloc = allocator<pair<const _Key, _Tp> > >
 class _LIBCPP_TEMPLATE_VIS unordered_map {
+  // TODO(#106635): replace with _LIBCPP_CHECK_CONTAINER_VALUE_TYPE_REQUIREMENTS
+  // Remember to remove relevant headers when this is completed.
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cjdb wrote:

I think MS/STL is allowing these as an extension? The linked wording from #106635 already prohibits `unordered_map<int, int&>`. We weren't catching it before, and have been Hyrum's Law'd.

https://github.com/llvm/llvm-project/pull/106296