[libcxx] [llvm] [RFC][libc++] Reworks clang-tidy selection. (PR #81362)

[Louis Dionne via llvm-commits]

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@@ -0,0 +1,15 @@
+# The LLVM Version number information
+
+if(NOT DEFINED LLVM_VERSION_MAJOR)
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ldionne wrote:

I think this is worthwhile as its own change, and in particular we could probably derive `_LIBCPP_VERSION` from it, which would simplify the job of the release manager.

https://github.com/llvm/llvm-project/pull/81362