Index: lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPython.cpp
===================================================================
--- lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPython.cpp
+++ lldb/source/Plugins/ScriptInterpreter/Python/ScriptInterpreterPython.cpp
@@ -85,7 +85,7 @@
   return static_cast<ScriptInterpreterPythonImpl *>(script_interpreter);
 }
 
-static bool g_initialized = false;
+static std::atomic<bool> g_initialized(false);
 
 namespace {
 
@@ -3194,11 +3194,12 @@
 #endif
 
 void ScriptInterpreterPythonImpl::InitializePrivate() {
-  if (g_initialized)
+  bool initialized = false;
+  const bool exchanged =
+      g_initialized.compare_exchange_strong(initialized, true);
+  if (!exchanged)
     return;
 
-  g_initialized = true;
-
   LLDB_SCOPED_TIMER();
 
   // RAII-based initialization which correctly handles multiple-initialization,