diff --git a/googlemock/src/gmock-spec-builders.cc b/googlemock/src/gmock-spec-builders.cc
index de894716..fb67ab09 100644
--- a/googlemock/src/gmock-spec-builders.cc
+++ b/googlemock/src/gmock-spec-builders.cc
@@ -490,6 +490,7 @@ class MockObjectRegistry {
   // failure, unless the user explicitly asked us to ignore it.
   ~MockObjectRegistry() {
     if (!GMOCK_FLAG_GET(catch_leaked_mocks)) return;
+    internal::MutexLock l(&internal::g_gmock_mutex);
 
     int leaked_count = 0;
     for (StateMap::const_iterator it = states_.begin(); it != states_.end();