diff --git a/compiler-rt/lib/tsan/tests/rtl/tsan_bench.cpp b/compiler-rt/lib/tsan/tests/rtl/tsan_bench.cpp
--- a/compiler-rt/lib/tsan/tests/rtl/tsan_bench.cpp
+++ b/compiler-rt/lib/tsan/tests/rtl/tsan_bench.cpp
@@ -89,7 +89,7 @@
 }
 
 TEST(DISABLED_BENCH, MutexLocal) {
-  Mutex m;
+  UserMutex m;
   ScopedThread().Create(m);
   for (int i = 0; i < 50; i++) {
     ScopedThread t;
diff --git a/compiler-rt/lib/tsan/tests/rtl/tsan_mop.cpp b/compiler-rt/lib/tsan/tests/rtl/tsan_mop.cpp
--- a/compiler-rt/lib/tsan/tests/rtl/tsan_mop.cpp
+++ b/compiler-rt/lib/tsan/tests/rtl/tsan_mop.cpp
@@ -65,7 +65,7 @@
 }
 
 TEST(ThreadSanitizer, WriteThenLockedRead) {
-  Mutex m(Mutex::RW);
+  UserMutex m(UserMutex::RW);
   MainThread t0;
   t0.Create(m);
   MemLoc l;
@@ -84,7 +84,7 @@
 }
 
 TEST(ThreadSanitizer, LockedWriteThenRead) {
-  Mutex m(Mutex::RW);
+  UserMutex m(UserMutex::RW);
   MainThread t0;
   t0.Create(m);
   MemLoc l;
diff --git a/compiler-rt/lib/tsan/tests/rtl/tsan_mutex.cpp b/compiler-rt/lib/tsan/tests/rtl/tsan_mutex.cpp
--- a/compiler-rt/lib/tsan/tests/rtl/tsan_mutex.cpp
+++ b/compiler-rt/lib/tsan/tests/rtl/tsan_mutex.cpp
@@ -20,7 +20,7 @@
 
 TEST(ThreadSanitizer, BasicMutex) {
   ScopedThread t;
-  Mutex m;
+  UserMutex m;
   t.Create(m);
 
   t.Lock(m);
@@ -38,7 +38,7 @@
 
 TEST(ThreadSanitizer, BasicSpinMutex) {
   ScopedThread t;
-  Mutex m(Mutex::Spin);
+  UserMutex m(UserMutex::Spin);
   t.Create(m);
 
   t.Lock(m);
@@ -56,7 +56,7 @@
 
 TEST(ThreadSanitizer, BasicRwMutex) {
   ScopedThread t;
-  Mutex m(Mutex::RW);
+  UserMutex m(UserMutex::RW);
   t.Create(m);
 
   t.Lock(m);
@@ -92,7 +92,7 @@
 }
 
 TEST(ThreadSanitizer, Mutex) {
-  Mutex m;
+  UserMutex m;
   MainThread t0;
   t0.Create(m);
 
@@ -108,7 +108,7 @@
 }
 
 TEST(ThreadSanitizer, SpinMutex) {
-  Mutex m(Mutex::Spin);
+  UserMutex m(UserMutex::Spin);
   MainThread t0;
   t0.Create(m);
 
@@ -124,7 +124,7 @@
 }
 
 TEST(ThreadSanitizer, RwMutex) {
-  Mutex m(Mutex::RW);
+  UserMutex m(UserMutex::RW);
   MainThread t0;
   t0.Create(m);
 
@@ -150,7 +150,7 @@
 
 TEST(ThreadSanitizer, StaticMutex) {
   // Emulates statically initialized mutex.
-  Mutex m;
+  UserMutex m;
   m.StaticInit();
   {
     ScopedThread t1, t2;
diff --git a/compiler-rt/lib/tsan/tests/rtl/tsan_test_util.h b/compiler-rt/lib/tsan/tests/rtl/tsan_test_util.h
--- a/compiler-rt/lib/tsan/tests/rtl/tsan_test_util.h
+++ b/compiler-rt/lib/tsan/tests/rtl/tsan_test_util.h
@@ -28,7 +28,7 @@
   void operator = (const MemLoc&);
 };
 
-class Mutex {
+class UserMutex {
  public:
   enum Type {
     Normal,
@@ -40,8 +40,8 @@
 #endif
   };
 
-  explicit Mutex(Type type = Normal);
-  ~Mutex();
+  explicit UserMutex(Type type = Normal);
+  ~UserMutex();
 
   void Init();
   void StaticInit();  // Emulates static initialization (tsan invisible).
@@ -59,8 +59,8 @@
   bool alive_;
   const Type type_;
 
-  Mutex(const Mutex&);
-  void operator = (const Mutex&);
+  UserMutex(const UserMutex &);
+  void operator=(const UserMutex &);
 };
 
 // A thread is started in CTOR and joined in DTOR.
@@ -100,14 +100,14 @@
   void Call(void(*pc)());
   void Return();
 
-  void Create(const Mutex &m);
-  void Destroy(const Mutex &m);
-  void Lock(const Mutex &m);
-  bool TryLock(const Mutex &m);
-  void Unlock(const Mutex &m);
-  void ReadLock(const Mutex &m);
-  bool TryReadLock(const Mutex &m);
-  void ReadUnlock(const Mutex &m);
+  void Create(const UserMutex &m);
+  void Destroy(const UserMutex &m);
+  void Lock(const UserMutex &m);
+  bool TryLock(const UserMutex &m);
+  void Unlock(const UserMutex &m);
+  void ReadLock(const UserMutex &m);
+  bool TryReadLock(const UserMutex &m);
+  void ReadUnlock(const UserMutex &m);
 
   void Memcpy(void *dst, const void *src, int size, bool expect_race = false);
   void Memset(void *dst, int val, int size, bool expect_race = false);
diff --git a/compiler-rt/lib/tsan/tests/rtl/tsan_test_util_posix.cpp b/compiler-rt/lib/tsan/tests/rtl/tsan_test_util_posix.cpp
--- a/compiler-rt/lib/tsan/tests/rtl/tsan_test_util_posix.cpp
+++ b/compiler-rt/lib/tsan/tests/rtl/tsan_test_util_posix.cpp
@@ -90,16 +90,11 @@
 MemLoc::~MemLoc() {
 }
 
-Mutex::Mutex(Type type)
-  : alive_()
-  , type_(type) {
-}
+UserMutex::UserMutex(Type type) : alive_(), type_(type) {}
 
-Mutex::~Mutex() {
-  CHECK(!alive_);
-}
+UserMutex::~UserMutex() { CHECK(!alive_); }
 
-void Mutex::Init() {
+void UserMutex::Init() {
   CHECK(!alive_);
   alive_ = true;
   if (type_ == Normal)
@@ -114,7 +109,7 @@
     CHECK(0);
 }
 
-void Mutex::StaticInit() {
+void UserMutex::StaticInit() {
   CHECK(!alive_);
   CHECK(type_ == Normal);
   alive_ = true;
@@ -122,7 +117,7 @@
   memcpy(mtx_, &tmp, sizeof(tmp));
 }
 
-void Mutex::Destroy() {
+void UserMutex::Destroy() {
   CHECK(alive_);
   alive_ = false;
   if (type_ == Normal)
@@ -135,7 +130,7 @@
     CHECK_EQ(__interceptor_pthread_rwlock_destroy((pthread_rwlock_t*)mtx_), 0);
 }
 
-void Mutex::Lock() {
+void UserMutex::Lock() {
   CHECK(alive_);
   if (type_ == Normal)
     CHECK_EQ(__interceptor_pthread_mutex_lock((pthread_mutex_t*)mtx_), 0);
@@ -147,7 +142,7 @@
     CHECK_EQ(__interceptor_pthread_rwlock_wrlock((pthread_rwlock_t*)mtx_), 0);
 }
 
-bool Mutex::TryLock() {
+bool UserMutex::TryLock() {
   CHECK(alive_);
   if (type_ == Normal)
     return __interceptor_pthread_mutex_trylock((pthread_mutex_t*)mtx_) == 0;
@@ -160,7 +155,7 @@
   return false;
 }
 
-void Mutex::Unlock() {
+void UserMutex::Unlock() {
   CHECK(alive_);
   if (type_ == Normal)
     CHECK_EQ(__interceptor_pthread_mutex_unlock((pthread_mutex_t*)mtx_), 0);
@@ -172,19 +167,19 @@
     CHECK_EQ(__interceptor_pthread_rwlock_unlock((pthread_rwlock_t*)mtx_), 0);
 }
 
-void Mutex::ReadLock() {
+void UserMutex::ReadLock() {
   CHECK(alive_);
   CHECK(type_ == RW);
   CHECK_EQ(__interceptor_pthread_rwlock_rdlock((pthread_rwlock_t*)mtx_), 0);
 }
 
-bool Mutex::TryReadLock() {
+bool UserMutex::TryReadLock() {
   CHECK(alive_);
   CHECK(type_ == RW);
   return __interceptor_pthread_rwlock_tryrdlock((pthread_rwlock_t*)mtx_) ==  0;
 }
 
-void Mutex::ReadUnlock() {
+void UserMutex::ReadUnlock() {
   CHECK(alive_);
   CHECK(type_ == RW);
   CHECK_EQ(__interceptor_pthread_rwlock_unlock((pthread_rwlock_t*)mtx_), 0);
@@ -310,28 +305,28 @@
     __tsan_func_exit();
     break;
   case Event::MUTEX_CREATE:
-    static_cast<Mutex*>(ev->ptr)->Init();
+    static_cast<UserMutex *>(ev->ptr)->Init();
     break;
   case Event::MUTEX_DESTROY:
-    static_cast<Mutex*>(ev->ptr)->Destroy();
+    static_cast<UserMutex *>(ev->ptr)->Destroy();
     break;
   case Event::MUTEX_LOCK:
-    static_cast<Mutex*>(ev->ptr)->Lock();
+    static_cast<UserMutex *>(ev->ptr)->Lock();
     break;
   case Event::MUTEX_TRYLOCK:
-    ev->res = static_cast<Mutex*>(ev->ptr)->TryLock();
+    ev->res = static_cast<UserMutex *>(ev->ptr)->TryLock();
     break;
   case Event::MUTEX_UNLOCK:
-    static_cast<Mutex*>(ev->ptr)->Unlock();
+    static_cast<UserMutex *>(ev->ptr)->Unlock();
     break;
   case Event::MUTEX_READLOCK:
-    static_cast<Mutex*>(ev->ptr)->ReadLock();
+    static_cast<UserMutex *>(ev->ptr)->ReadLock();
     break;
   case Event::MUTEX_TRYREADLOCK:
-    ev->res = static_cast<Mutex*>(ev->ptr)->TryReadLock();
+    ev->res = static_cast<UserMutex *>(ev->ptr)->TryReadLock();
     break;
   case Event::MUTEX_READUNLOCK:
-    static_cast<Mutex*>(ev->ptr)->ReadUnlock();
+    static_cast<UserMutex *>(ev->ptr)->ReadUnlock();
     break;
   case Event::MEMCPY:
     __interceptor_memcpy(ev->ptr, (void*)ev->arg, ev->arg2);
@@ -440,44 +435,44 @@
   impl_->send(&event);
 }
 
-void ScopedThread::Create(const Mutex &m) {
+void ScopedThread::Create(const UserMutex &m) {
   Event event(Event::MUTEX_CREATE, &m);
   impl_->send(&event);
 }
 
-void ScopedThread::Destroy(const Mutex &m) {
+void ScopedThread::Destroy(const UserMutex &m) {
   Event event(Event::MUTEX_DESTROY, &m);
   impl_->send(&event);
 }
 
-void ScopedThread::Lock(const Mutex &m) {
+void ScopedThread::Lock(const UserMutex &m) {
   Event event(Event::MUTEX_LOCK, &m);
   impl_->send(&event);
 }
 
-bool ScopedThread::TryLock(const Mutex &m) {
+bool ScopedThread::TryLock(const UserMutex &m) {
   Event event(Event::MUTEX_TRYLOCK, &m);
   impl_->send(&event);
   return event.res;
 }
 
-void ScopedThread::Unlock(const Mutex &m) {
+void ScopedThread::Unlock(const UserMutex &m) {
   Event event(Event::MUTEX_UNLOCK, &m);
   impl_->send(&event);
 }
 
-void ScopedThread::ReadLock(const Mutex &m) {
+void ScopedThread::ReadLock(const UserMutex &m) {
   Event event(Event::MUTEX_READLOCK, &m);
   impl_->send(&event);
 }
 
-bool ScopedThread::TryReadLock(const Mutex &m) {
+bool ScopedThread::TryReadLock(const UserMutex &m) {
   Event event(Event::MUTEX_TRYREADLOCK, &m);
   impl_->send(&event);
   return event.res;
 }
 
-void ScopedThread::ReadUnlock(const Mutex &m) {
+void ScopedThread::ReadUnlock(const UserMutex &m) {
   Event event(Event::MUTEX_READUNLOCK, &m);
   impl_->send(&event);
 }