diff --git a/extensions/openpower-pels/mtms.hpp b/extensions/openpower-pels/mtms.hpp
index 928fb74..ce157a7 100644
--- a/extensions/openpower-pels/mtms.hpp
+++ b/extensions/openpower-pels/mtms.hpp
@@ -2,6 +2,7 @@
 
 #include "stream.hpp"
 
+#include <array>
 #include <string>
 
 namespace openpower