--- a/ipc/ipdl/test/cxx/TestBadActor.h
+++ b/ipc/ipdl/test/cxx/TestBadActor.h
@@ -29,35 +29,35 @@ protected:
   {
     if (AbnormalShutdown != why)
       fail("unexpected destruction");
     passed("ok");
     QuitParent();
   }
 
   virtual PTestBadActorSubParent*
-  AllocPTestBadActorSubParent();
+  AllocPTestBadActorSubParent() override;
 
   virtual bool
-  DeallocPTestBadActorSubParent(PTestBadActorSubParent* actor) {
+  DeallocPTestBadActorSubParent(PTestBadActorSubParent* actor) override {
     delete actor;
     return true;
   }
 };
 
 class TestBadActorSubParent
   : public PTestBadActorSubParent
 {
 public:
   TestBadActorSubParent() { }
   virtual ~TestBadActorSubParent() { }
 
 protected:
   virtual void ActorDestroy(ActorDestroyReason why) override {}
-  virtual bool RecvPing();
+  virtual bool RecvPing() override;
 };
 
 class TestBadActorChild
   : public PTestBadActorChild
 {
 public:
   TestBadActorChild() { }
   virtual ~TestBadActorChild() { }

--- a/ipc/ipdl/test/cxx/TestEndpointOpens.h
+++ b/ipc/ipdl/test/cxx/TestEndpointOpens.h
@@ -25,17 +25,17 @@ public:
   virtual ~TestEndpointOpensParent() {}
 
   static bool RunTestInProcesses() { return true; }
   static bool RunTestInThreads() { return false; }
 
   void Main();
 
 protected:
-  virtual bool RecvStartSubprotocol(mozilla::ipc::Endpoint<PTestEndpointOpensOpenedParent>&& endpoint);
+  virtual bool RecvStartSubprotocol(mozilla::ipc::Endpoint<PTestEndpointOpensOpenedParent>&& endpoint) override;
 
   virtual void ActorDestroy(ActorDestroyReason why) override;
 };
 
 } // namespace _ipdltest
 
 namespace _ipdltest2 {
 

--- a/ipc/ipdl/test/cxx/TestHangs.h
+++ b/ipc/ipdl/test/cxx/TestHangs.h
@@ -23,17 +23,17 @@ public:
     //                  clear how that should work in threads.
     static bool RunTestInThreads() { return false; }
 
     void Main();
 
 protected:
     virtual bool ShouldContinueFromReplyTimeout() override;
 
-    virtual bool RecvNonce() {
+    virtual bool RecvNonce() override {
         return true;
     }
 
     virtual bool AnswerStackFrame() override;
 
     virtual void ActorDestroy(ActorDestroyReason why) override
     {
         if (AbnormalShutdown != why)

--- a/ipc/ipdl/test/cxx/TestShutdown.h
+++ b/ipc/ipdl/test/cxx/TestShutdown.h
@@ -192,17 +192,17 @@ public:
     {
     }
     virtual ~TestShutdownChild()
     {
     }
 
 protected:
     virtual bool
-    RecvStart();
+    RecvStart() override;
 
     virtual PTestShutdownSubChild*
     AllocPTestShutdownSubChild(
         const bool& expectCrash) override
     {
         return new TestShutdownSubChild(expectCrash);
     }
 

--- a/ipc/ipdl/test/cxx/TestUrgency.h
+++ b/ipc/ipdl/test/cxx/TestUrgency.h
@@ -17,22 +17,22 @@ public:
     TestUrgencyParent();
     virtual ~TestUrgencyParent();
 
     static bool RunTestInProcesses() { return true; }
     static bool RunTestInThreads() { return false; }
 
     void Main();
 
-    bool RecvTest1(uint32_t *value);
-    bool RecvTest2();
-    bool RecvTest3(uint32_t *value);
+    bool RecvTest1(uint32_t *value) override;
+    bool RecvTest2() override;
+    bool RecvTest3(uint32_t *value) override;
     bool RecvTest4_Begin();
     bool RecvTest4_NestedSync();
-    bool RecvFinalTest_Begin();
+    bool RecvFinalTest_Begin() override;
 
     bool ShouldContinueFromReplyTimeout() override
     {
       return false;
     }
     virtual void ActorDestroy(ActorDestroyReason why) override
     {
         passed("ok");
@@ -46,19 +46,19 @@ private:
 
 class TestUrgencyChild :
     public PTestUrgencyChild
 {
 public:
     TestUrgencyChild();
     virtual ~TestUrgencyChild();
 
-    bool RecvStart();
-    bool RecvReply1(uint32_t *reply);
-    bool RecvReply2(uint32_t *reply);
+    bool RecvStart() override;
+    bool RecvReply1(uint32_t *reply) override;
+    bool RecvReply2(uint32_t *reply) override;
 
     virtual void ActorDestroy(ActorDestroyReason why) override
     {
         QuitChild();
     }
 
 private:
     uint32_t test_;

--- a/ipc/ipdl/test/cxx/TestUrgentHangs.h
+++ b/ipc/ipdl/test/cxx/TestUrgentHangs.h
@@ -19,19 +19,19 @@ public:
 
     static bool RunTestInProcesses() { return true; }
     static bool RunTestInThreads() { return false; }
 
     void Main();
     void SecondStage();
     void ThirdStage();
 
-    bool RecvTest1_2();
-    bool RecvTestInner();
-    bool RecvTestInnerUrgent();
+    bool RecvTest1_2() override;
+    bool RecvTestInner() override;
+    bool RecvTestInnerUrgent() override;
 
     bool ShouldContinueFromReplyTimeout() override
     {
       return false;
     }
     virtual void ActorDestroy(ActorDestroyReason why) override
     {
 	if (mInnerCount != 1) {
@@ -51,24 +51,24 @@ private:
 
 class TestUrgentHangsChild :
     public PTestUrgentHangsChild
 {
 public:
     TestUrgentHangsChild();
     virtual ~TestUrgentHangsChild();
 
-    bool RecvTest1_1();
-    bool RecvTest1_3();
-    bool RecvTest2();
-    bool RecvTest3();
-    bool RecvTest4();
-    bool RecvTest4_1();
-    bool RecvTest5();
-    bool RecvTest5_1();
+    bool RecvTest1_1() override;
+    bool RecvTest1_3() override;
+    bool RecvTest2() override;
+    bool RecvTest3() override;
+    bool RecvTest4() override;
+    bool RecvTest4_1() override;
+    bool RecvTest5() override;
+    bool RecvTest5_1() override;
 
     virtual void ActorDestroy(ActorDestroyReason why) override
     {
         QuitChild();
     }
 };