[libcxx-commits] [libcxx] [libc++] Fix `optional<T>::transform` into `optional<T&>` (PR #221506)

[A. Jiang via libcxx-commits]

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frederick-vs-ja wrote:

Would you mind to refer the issue using https://llvm.org/PR220332 in the comments?

https://github.com/llvm/llvm-project/pull/221506