SERVER-28839 Unbind the impl from the proxy before terminating the thread

1 files changed, 6 insertions, 0 deletions

diff --git a/src/mongo/scripting/mozjs/proxyscope.cpp b/src/mongo/scripting/mozjs/proxyscope.cpp
index 78bccb1871b..fec94a88a97 100644
--- a/src/mongo/scripting/mozjs/proxyscope.cpp
+++ b/src/mongo/scripting/mozjs/proxyscope.cpp
@@ -38,6 +38,7 @@
 #include "mongo/util/concurrency/idle_thread_block.h"
 #include "mongo/util/destructor_guard.h"
 #include "mongo/util/quick_exit.h"
+#include "mongo/util/scopeguard.h"
 
 namespace mongo {
 namespace mozjs {
@@ -338,6 +339,11 @@ void MozJSProxyScope::implThread(void* arg) {
         proxy->_status = exceptionToStatus();
     }
 
+    // This is mostly to silence coverity, so that it sees that the
+    // ProxyScope doesn't hold a reference to the ImplScope after it
+    // is deleted by the unique_ptr.
+    const auto unbindImplScope = MakeGuard([&proxy] { proxy->_implScope = nullptr; });
+
     while (true) {
         stdx::unique_lock<stdx::mutex> lk(proxy->_mutex);
         {