[clang] [clang] Reject __super when preceded by a scope specifier (PR #221492)

[Shafik Yaghmour via cfe-commits]

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@@ -21,6 +21,13 @@ struct Base1 {
   typedef int XXX;
 };
 
+struct InvalidGlobalQualifier : Base1 {
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shafik wrote:

Normally we wrap regression tests in a namespace named after the issues number e.g in this case `namespace GH212988`

https://github.com/llvm/llvm-project/pull/221492