1 files changed, 1 insertions, 1 deletions
diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc
index bb4b5c5dab..25c0b9ea8e 100644
--- a/runtime/base/mutex.cc
+++ b/runtime/base/mutex.cc
@@ -94,7 +94,7 @@ std::set<BaseMutex*>* all_mutexes_;
 
 class ScopedAllMutexesLock {
  public:
-  ScopedAllMutexesLock(const BaseMutex* mutex) : mutex_(mutex) {
+  explicit ScopedAllMutexesLock(const BaseMutex* mutex) : mutex_(mutex) {
     while (!all_mutexes_guard_.CompareAndSwap(0, reinterpret_cast<int32_t>(mutex))) {
       NanoSleep(100);
     }