diff --git a/cmds/idmap2/libidmap2/CommandLineOptions.cpp b/cmds/idmap2/libidmap2/CommandLineOptions.cpp
index 888b3a5..2da05b3 100644
--- a/cmds/idmap2/libidmap2/CommandLineOptions.cpp
+++ b/cmds/idmap2/libidmap2/CommandLineOptions.cpp
@@ -19,6 +19,7 @@
 #include <algorithm>
 #include <cassert>
 #include <iomanip>
+#include <iterator>
 #include <memory>
 #include <ostream>
 #include <set>