diff --git a/src/script_opt/ProfileFunc.cc b/src/script_opt/ProfileFunc.cc
index f629c4c20d..f96545b254 100644
--- a/src/script_opt/ProfileFunc.cc
+++ b/src/script_opt/ProfileFunc.cc
@@ -1,6 +1,7 @@
 // See the file "COPYING" in the main distribution directory for copyright.
 
 #include <unistd.h>
+#include <cerrno>
 
 #include "zeek/script_opt/ProfileFunc.h"
 #include "zeek/Desc.h"