Index: clang/tools/libclang/CIndex.cpp
===================================================================
--- clang/tools/libclang/CIndex.cpp
+++ clang/tools/libclang/CIndex.cpp
@@ -22,6 +22,7 @@
 #include "CursorVisitor.h"
 #include "clang-c/FatalErrorHandler.h"
 #include "clang/AST/Attr.h"
+#include "clang/AST/AttrVisitor.h"
 #include "clang/AST/DeclObjCCommon.h"
 #include "clang/AST/Mangle.h"
 #include "clang/AST/OpenMPClause.h"
@@ -523,6 +524,13 @@
     return false;
   }
 
+  if (clang_isAttribute(Cursor.kind)) {
+    if (const Attr *A = getCursorAttr(Cursor))
+      return Visit(A);
+
+    return false;
+  }
+
   if (clang_isTranslationUnit(Cursor.kind)) {
     CXTranslationUnit TU = getCursorTU(Cursor);
     ASTUnit *CXXUnit = cxtu::getASTUnit(TU);
@@ -2085,7 +2093,8 @@
         (SourceLocation::UIntTy)(uintptr_t)data[1]);
   }
 };
-class EnqueueVisitor : public ConstStmtVisitor<EnqueueVisitor, void> {
+class EnqueueVisitor : public ConstStmtVisitor<EnqueueVisitor, void>,
+                       public ConstAttrVisitor<EnqueueVisitor, void> {
   friend class OMPClauseEnqueue;
   VisitorWorkList &WL;
   CXCursor Parent;
@@ -2227,6 +2236,10 @@
   void VisitOMPTargetTeamsDistributeSimdDirective(
       const OMPTargetTeamsDistributeSimdDirective *D);
 
+  // Attributes
+  void VisitAnnotateAttr(const AnnotateAttr *A);
+  void VisitAnnotateTypeAttr(const AnnotateTypeAttr *A);
+
 private:
   void AddDeclarationNameInfo(const Stmt *S);
   void AddNestedNameSpecifierLoc(NestedNameSpecifierLoc Qualifier);
@@ -2238,6 +2251,8 @@
   void AddTypeLoc(TypeSourceInfo *TI);
   void EnqueueChildren(const Stmt *S);
   void EnqueueChildren(const OMPClause *S);
+  void EnqueueChildren(const AnnotateAttr *A);
+  void EnqueueChildren(const AnnotateTypeAttr *A);
 };
 } // namespace
 
@@ -2727,6 +2742,31 @@
   VisitorWorkList::iterator I = WL.begin() + size, E = WL.end();
   std::reverse(I, E);
 }
+// TODO these two methods are exactly the same. Can this be expressed better?
+void EnqueueVisitor::EnqueueChildren(const AnnotateAttr *A) {
+  unsigned size = WL.size();
+  for (const Expr *Arg : A->args()) {
+    VisitStmt(Arg);
+  }
+  if (size == WL.size())
+    return;
+  // Now reverse the entries we just added.  This will match the DFS
+  // ordering performed by the worklist.
+  VisitorWorkList::iterator I = WL.begin() + size, E = WL.end();
+  std::reverse(I, E);
+}
+void EnqueueVisitor::EnqueueChildren(const AnnotateTypeAttr *A) {
+  unsigned size = WL.size();
+  for (const Expr *Arg : A->args()) {
+    AddStmt(Arg);
+  }
+  if (size == WL.size())
+    return;
+  // Now reverse the entries we just added.  This will match the DFS
+  // ordering performed by the worklist.
+  VisitorWorkList::iterator I = WL.begin() + size, E = WL.end();
+  std::reverse(I, E);
+}
 void EnqueueVisitor::VisitAddrLabelExpr(const AddrLabelExpr *E) {
   WL.push_back(LabelRefVisit(E->getLabel(), E->getLabelLoc(), Parent));
 }
@@ -2999,7 +3039,7 @@
   // If the opaque value has a source expression, just transparently
   // visit that.  This is useful for (e.g.) pseudo-object expressions.
   if (Expr *SourceExpr = E->getSourceExpr())
-    return Visit(SourceExpr);
+    return ConstStmtVisitor::Visit(SourceExpr);
 }
 void EnqueueVisitor::VisitLambdaExpr(const LambdaExpr *E) {
   AddStmt(E->getBody());
@@ -3019,7 +3059,7 @@
 }
 void EnqueueVisitor::VisitPseudoObjectExpr(const PseudoObjectExpr *E) {
   // Treat the expression like its syntactic form.
-  Visit(E->getSyntacticForm());
+  ConstStmtVisitor::Visit(E->getSyntacticForm());
 }
 
 void EnqueueVisitor::VisitOMPExecutableDirective(
@@ -3329,9 +3369,32 @@
   VisitOMPLoopDirective(D);
 }
 
+void EnqueueVisitor::VisitAnnotateAttr(const AnnotateAttr *A) {
+  EnqueueChildren(A);
+}
+
+void EnqueueVisitor::VisitAnnotateTypeAttr(const AnnotateTypeAttr *A) {
+  EnqueueChildren(A);
+}
+
 void CursorVisitor::EnqueueWorkList(VisitorWorkList &WL, const Stmt *S) {
   EnqueueVisitor(WL, MakeCXCursor(S, StmtParent, TU, RegionOfInterest))
-      .Visit(S);
+      .ConstStmtVisitor::Visit(S);
+}
+
+void CursorVisitor::EnqueueWorkList(VisitorWorkList &WL, const Attr *A) {
+  // Parent is the attribute itself when this is indirectly called from
+  // VisitChildren. Because we need to make a CXCursor for A, we need *its*
+  // parent.
+  auto AttrCursor = Parent;
+
+  // Get the attribute's parent as stored in
+  // cxcursor::MakeCXCursor(const Attr *A, const Decl *Parent, CXTranslationUnit
+  // TU)
+  const Decl *AttrParent = static_cast<const Decl *>(AttrCursor.data[1]);
+
+  EnqueueVisitor(WL, MakeCXCursor(A, AttrParent, TU))
+      .ConstAttrVisitor::Visit(A);
 }
 
 bool CursorVisitor::IsInRegionOfInterest(CXCursor C) {
@@ -3596,6 +3659,22 @@
   return result;
 }
 
+bool CursorVisitor::Visit(const Attr *A) {
+  VisitorWorkList *WL = nullptr;
+  if (!WorkListFreeList.empty()) {
+    WL = WorkListFreeList.back();
+    WL->clear();
+    WorkListFreeList.pop_back();
+  } else {
+    WL = new VisitorWorkList();
+    WorkListCache.push_back(WL);
+  }
+  EnqueueWorkList(*WL, A);
+  bool result = RunVisitorWorkList(*WL);
+  WorkListFreeList.push_back(WL);
+  return result;
+}
+
 namespace {
 typedef SmallVector<SourceRange, 4> RefNamePieces;
 RefNamePieces buildPieces(unsigned NameFlags, bool IsMemberRefExpr,
Index: clang/tools/libclang/CursorVisitor.h
===================================================================
--- clang/tools/libclang/CursorVisitor.h
+++ clang/tools/libclang/CursorVisitor.h
@@ -276,7 +276,9 @@
   bool IsInRegionOfInterest(CXCursor C);
   bool RunVisitorWorkList(VisitorWorkList &WL);
   void EnqueueWorkList(VisitorWorkList &WL, const Stmt *S);
+  void EnqueueWorkList(VisitorWorkList &WL, const Attr *A);
   LLVM_ATTRIBUTE_NOINLINE bool Visit(const Stmt *S);
+  LLVM_ATTRIBUTE_NOINLINE bool Visit(const Attr *A);
 
 private:
   std::optional<bool> handleDeclForVisitation(const Decl *D);