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diff --git a/examples/AnnotateFunctions/AnnotateFunctions.cpp b/examples/AnnotateFunctions/AnnotateFunctions.cpp
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index 000000000000..375f18f8e09a
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+++ b/examples/AnnotateFunctions/AnnotateFunctions.cpp
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+//===- AnnotateFunctions.cpp ----------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Example clang plugin which adds an annotation to every function in
+// translation units that start with #pragma enable_annotate.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/FrontendPluginRegistry.h"
+#include "clang/AST/AST.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/LexDiagnostic.h"
+using namespace clang;
+
+namespace {
+
+static bool EnableAnnotate = false;
+static bool HandledDecl = false;
+
+class AnnotateFunctionsConsumer : public ASTConsumer {
+public:
+  bool HandleTopLevelDecl(DeclGroupRef DG) override {
+    HandledDecl = true;
+    if (!EnableAnnotate)
+      return true;
+    for (auto D : DG)
+      if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
+        FD->addAttr(AnnotateAttr::CreateImplicit(FD->getASTContext(),
+                                                 "example_annotation"));
+    return true;
+  }
+};
+
+class AnnotateFunctionsAction : public PluginASTAction {
+public:
+  std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
+                                                 llvm::StringRef) override {
+    return llvm::make_unique<AnnotateFunctionsConsumer>();
+  }
+
+  bool ParseArgs(const CompilerInstance &CI,
+                 const std::vector<std::string> &args) override {
+    return true;
+  }
+
+  PluginASTAction::ActionType getActionType() override {
+    return AddBeforeMainAction;
+  }
+};
+
+class PragmaAnnotateHandler : public PragmaHandler {
+public:
+  PragmaAnnotateHandler() : PragmaHandler("enable_annotate") { }
+
+  void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
+                    Token &PragmaTok) override {
+
+    Token Tok;
+    PP.LexUnexpandedToken(Tok);
+    if (Tok.isNot(tok::eod))
+      PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma";
+
+    if (HandledDecl) {
+      DiagnosticsEngine &D = PP.getDiagnostics();
+      unsigned ID = D.getCustomDiagID(
+        DiagnosticsEngine::Error,
+        "#pragma enable_annotate not allowed after declarations");
+      D.Report(PragmaTok.getLocation(), ID);
+    }
+
+    EnableAnnotate = true;
+  }
+};
+
+}
+
+static FrontendPluginRegistry::Add<AnnotateFunctionsAction>
+X("annotate-fns", "annotate functions");
+
+static PragmaHandlerRegistry::Add<PragmaAnnotateHandler>
+Y("enable_annotate","enable annotation");