1 files changed, 2 insertions, 0 deletions
diff --git a/hash.cxx b/hash.cxx
index e1e24af9..24ce92d5 100644
--- a/hash.cxx
+++ b/hash.cxx
@@ -19,6 +19,8 @@
 #include "session.h"
 #include "hash.h"
 #include "util.h"
+
+#include <cstdlib>
 #include <sstream>
 #include <iomanip>
 #include <cerrno>