diff --git a/eo/test/mpi/t-mpi-parallelApply.cpp b/eo/test/mpi/t-mpi-parallelApply.cpp
index 04985b3f7..6cda89907 100644
--- a/eo/test/mpi/t-mpi-parallelApply.cpp
+++ b/eo/test/mpi/t-mpi-parallelApply.cpp
@@ -46,6 +46,7 @@ Authors:
 # include "t-mpi-common.h"
 
 # include <iostream>
+# include <cstdlib>
 
 # include <vector>
 using namespace std;
diff --git a/eo/test/mpi/t-mpi-wrapper.cpp b/eo/test/mpi/t-mpi-wrapper.cpp
index 7da45ad4e..cedc717fe 100644
--- a/eo/test/mpi/t-mpi-wrapper.cpp
+++ b/eo/test/mpi/t-mpi-wrapper.cpp
@@ -36,6 +36,7 @@ Authors:
 # include "t-mpi-common.h"
 
 # include <iostream>
+# include <cstdlib>
 
 # include <vector>
 using namespace std;