diff --git a/compiler2/ttcn3/Ttcnstuff.cc b/compiler2/ttcn3/Ttcnstuff.cc
index 5e067ab648c2e381023ba49b94c90913f374805f..d198034b9ab844b610a6ad521fd904087918b197 100644
--- a/compiler2/ttcn3/Ttcnstuff.cc
+++ b/compiler2/ttcn3/Ttcnstuff.cc
@@ -29,6 +29,7 @@
 #include "../../common/path.h"
 #include "../../common/userinfo.h"
 #include "../../common/version_internal.h"
+#include <stdlib.h>
 
 // implemented in coding_attrib_p.y
 extern Ttcn::ExtensionAttributes * parse_extattributes(