diff --git a/source/adios2/toolkit/derived/Expression.cpp b/source/adios2/toolkit/derived/Expression.cpp
index df6c254b6c..744adfdc7f 100644
--- a/source/adios2/toolkit/derived/Expression.cpp
+++ b/source/adios2/toolkit/derived/Expression.cpp
@@ -6,6 +6,8 @@
 #include "adios2/helper/adiosLog.h"
 #include "parser/ASTDriver.h"
 
+#include <functional>
+
 namespace adios2
 {
 namespace detail
diff --git a/source/adios2/toolkit/derived/Function.tcc b/source/adios2/toolkit/derived/Function.tcc
index 0c6a2f0cf4..36d9ad483a 100644
--- a/source/adios2/toolkit/derived/Function.tcc
+++ b/source/adios2/toolkit/derived/Function.tcc
@@ -3,8 +3,10 @@
 
 #include "Function.h"
 #include "adios2/helper/adiosLog.h"
+
 #include <algorithm>
 #include <cstring>
+#include <functional>
 #include <iostream>
 #include <numeric>