[clang] [Clang] Implement CWG2517 Useless restriction on use of parameter in constraint-expression (PR #132919)

[via cfe-commits]

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@@ -32,6 +32,26 @@ enum E2 : S<E2>::I { e };
 #endif
 } // namespace cwg2516
 
+namespace cwg2517 { // cwg2517: 23
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cor3ntin wrote:

Surely you mean 21?

https://github.com/llvm/llvm-project/pull/132919