diff --git a/cmds/idmap2/libidmap2/CommandLineOptions.cpp b/cmds/idmap2/libidmap2/CommandLineOptions.cpp
index 5b0ae92..8129d99 100644
--- a/cmds/idmap2/libidmap2/CommandLineOptions.cpp
+++ b/cmds/idmap2/libidmap2/CommandLineOptions.cpp
@@ -17,6 +17,7 @@
 #include "idmap2/CommandLineOptions.h"
 
 #include <algorithm>
+#include <cassert>
 #include <iomanip>
 #include <iostream>
 #include <memory>
diff --git a/cmds/idmap2/libidmap2/Idmap.cpp b/cmds/idmap2/libidmap2/Idmap.cpp
index 6515d55..06650f6 100644
--- a/cmds/idmap2/libidmap2/Idmap.cpp
+++ b/cmds/idmap2/libidmap2/Idmap.cpp
@@ -17,6 +17,7 @@
 #include "idmap2/Idmap.h"
 
 #include <algorithm>
+#include <cassert>
 #include <iostream>
 #include <iterator>
 #include <limits>