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

[via cfe-commits]

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@@ -81,7 +81,7 @@ Parser::DeclGroupPtrTy Parser::ParseNamespace(DeclaratorContext Context,
 
   ParsedAttributes attrs(AttrFactory);
 
-  auto ReadAttributes = [&] {
+  auto ReadAttributes = [&](bool TrailingAttrs) {
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cor3ntin wrote:

Pre-existing, but why is this not using MaybeParseAttributes ? @AaronBallman 

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