[clang] [Parser][BoundsSafety] Print attribute as macro if it's system defined (PR #107619)

[Yeoul Na via cfe-commits]

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@@ -1105,16 +1120,16 @@ enum AttributeDeclKind {
 
 inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &DB,
                                              const ParsedAttr &At) {
-  DB.AddTaggedVal(reinterpret_cast<uint64_t>(At.getAttrName()),
+  const IdentifierInfo *AttrName =
+      At.printAsMacro() ? At.getMacroIdentifier() : At.getAttrName();
+  DB.AddTaggedVal(reinterpret_cast<uint64_t>(AttrName),
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rapidsna wrote:

@erichkeane Currently, a note is emitted to show the line where it's expanded from that includes the original attribute spelling:  https://github.com/llvm/llvm-project/pull/107619/files#diff-3d962c5c4f372776e40887d273f9404efe3cd306f9915505d8566b791021914bR49

Not sure how I can suppress the follow-on note that lists macro expansions, but I can try the `ak_attr` approach as @AaronBallman suggested. 

https://github.com/llvm/llvm-project/pull/107619