diff --git a/test/scoped_set_thread_name_posix.cc b/test/scoped_set_thread_name_posix.cc
index 4720bc00..92c61bbf 100644
--- a/test/scoped_set_thread_name_posix.cc
+++ b/test/scoped_set_thread_name_posix.cc
@@ -17,6 +17,7 @@
 #include <errno.h>
 #include <pthread.h>
 
+#include <ostream>
 #include <string>
 
 #include "base/check.h"