[libcxx-commits] [libcxx] [libc++] Make sure that __desugars_to isn't tripped up by reference_wrapper and cv-refs (PR #132092)

[Louis Dionne via libcxx-commits]

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@@ -52,6 +52,24 @@ struct __totally_ordered_less_tag {};
 template <class _CanonicalTag, class _Operation, class... _Args>
 inline const bool __desugars_to_v = false;
 
+// For the purpose of determining whether something desugars to something else,
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ldionne wrote:

There is a subtlety here. This patch only disregards the cv-ref qualifiers on the operation itself, which would be `std::less` in this case. It does not disregard the cv-ref qualifiers on the arguments that are passed to the function.

https://github.com/llvm/llvm-project/pull/132092