[clang] [clang] Implement CWG2877 "Type-only lookup for using-enum-declarator" (PR #95399)

[Vlad Serebrennikov via cfe-commits]

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@@ -241,6 +238,13 @@ TPLa<int> a;
 
 } // namespace Thirteen
 
+namespace Fourteen {
+template<typename T>
+int A = T();
+
+using enum A<int>; // expected-error {{A is not an enumerated type}}
+} // namespace Fourteen
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Endilll wrote:

Yes. If you look at the rest of the file, you'll see tests `One` through `Thirteen`.

https://github.com/llvm/llvm-project/pull/95399