[clang] [clang] Add formal linkage to textual AST dump (PR #194600)

[Aaron Ballman via cfe-commits]

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@@ -2295,6 +2318,11 @@ void TextNodeDumper::VisitTypedefDecl(const TypedefDecl *D) {
   dumpType(D->getUnderlyingType());
   if (D->isModulePrivate())
     OS << " __module_private__";
+
+  const TagDecl *TD = D->getUnderlyingType()->getAsTagDecl();
+  if (TD && TD->getTypedefNameForAnonDecl()) {
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AaronBallman wrote:

Do we need to do anything to handle `ObjCTypeParamDecl` -- do those even have the notion of linkage for anonymous decls? CC @rjmccall @ahatanak 

https://github.com/llvm/llvm-project/pull/194600