[clang] [Clang] add fix-it hints for unknown attributes (PR #141305)

[Oleksandr T. via cfe-commits]

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@@ -7867,15 +7867,16 @@ void Sema::checkUnusedDeclAttributes(Declarator &D) {
 
 void Sema::DiagnoseUnknownAttribute(const ParsedAttr &AL) {
   std::string NormalizedFullName = '\'' + AL.getNormalizedFullName() + '\'';
+  SourceRange NR = AL.getNormalizedRange();
+  SourceLocation Loc = NR.getBegin();
+
   if (auto CorrectedFullName =
           AL.getCorrectedFullName(Context.getTargetInfo(), getLangOpts())) {
-    Diag(AL.getNormalizedRange().getBegin(),
-         diag::warn_unknown_attribute_ignored_suggestion)
-        << NormalizedFullName << *CorrectedFullName << AL.getNormalizedRange();
+    Diag(Loc, diag::warn_unknown_attribute_ignored_suggestion)
+        << NormalizedFullName << *CorrectedFullName
+        << FixItHint::CreateReplacement(NR, *CorrectedFullName) << NR;
   } else {
-    Diag(AL.getNormalizedRange().getBegin(),
-         diag::warn_unknown_attribute_ignored)
-        << NormalizedFullName << AL.getNormalizedRange();
+    Diag(Loc, diag::warn_unknown_attribute_ignored) << NormalizedFullName << NR;
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a-tarasyuk wrote:

@AaronBallman, thanks for the feedback. I replaced diag::warn_unknown_attribute_ignored with `DiagnoseUnknownAttribute` for known cases. Since this general message is used in many places, it might be worth reviewing all cases to see where it would be appropriate to use `DiagnoseUnknownAttribute` instead. If any additinal cases should be covered, I’d appreciate it if you could point them out — I’ll be happy to investigate., thanks.



https://github.com/llvm/llvm-project/pull/141305