diff --git a/src/runtime/thread.cpp b/src/runtime/thread.cpp
index 6aab3fbc6d17..cd53bae6adfd 100644
--- a/src/runtime/thread.cpp
+++ b/src/runtime/thread.cpp
@@ -9,6 +9,9 @@ Author: Leonardo de Moura
 #include <iostream>
 #ifdef LEAN_WINDOWS
 #include <windows.h>
+# ifdef LEAN_AUTO_THREAD_FINALIZATION
+#include <pthread.h>
+# endif
 #else
 #include <pthread.h>
 #endif