[clang] [Clang] Implement CWG2918 'Consideration of constraints for address of overloaded function' (PR #127773)

[Younan Zhang via cfe-commits]

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@@ -60,6 +60,90 @@ struct S {
 #endif
 } // namespace cwg2917
 
+namespace cwg2918 { // cwg2918: 21
+
+#if __cplusplus >= 202002L
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zyn0217 wrote:

Done. Now it tests `Example3` in C++11 onwards
(Example 1 contains constraint expressions so it needs c++20)

https://github.com/llvm/llvm-project/pull/127773