[libcxx-commits] [libcxx] [libc++] Fix bug where optional<T&> couldn't be constructed from a monadic operation (PR #203462)

[A. Jiang via libcxx-commits]

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@@ -104,6 +104,14 @@ constexpr bool test() {
     }) == i);
   }
 
+  {
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frederick-vs-ja wrote:

We need to include `<concepts>` in this file, which is necessary for Clang module builds.
It's a bit surprising that we didn't verify type sameness in this file before. Perhaps we should consistently added type sameness verification in a future PR.

https://github.com/llvm/llvm-project/pull/203462