[clang] [Clang] disallow attributes after namespace identifier (PR #121614)

[via cfe-commits]

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@@ -100,7 +103,7 @@ Parser::DeclGroupPtrTy Parser::ParseNamespace(DeclaratorContext Context,
     } while (MoreToParse);
   };
 
-  ReadAttributes();
+  ReadAttributes(/*TrailingAttrs*/ false);
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cor3ntin wrote:

I would just call `CheckProhibitedCXX11Attribute` here

https://github.com/llvm/llvm-project/pull/121614