Index: lldb/trunk/packages/Python/lldbsuite/test/functionalities/thread/backtrace_all/ParallelTask.cpp
===================================================================
--- lldb/trunk/packages/Python/lldbsuite/test/functionalities/thread/backtrace_all/ParallelTask.cpp
+++ lldb/trunk/packages/Python/lldbsuite/test/functionalities/thread/backtrace_all/ParallelTask.cpp
@@ -2,6 +2,7 @@
 #include <thread>
 #include <vector>
 #include <queue>
+#include <functional>
 #include <future>
 #include <iostream>
 #include <cassert>