diff --git a/kernel/driver.cc b/kernel/driver.cc
index 9acc58dc4..76c11853e 100644
--- a/kernel/driver.cc
+++ b/kernel/driver.cc
@@ -20,6 +20,7 @@
 #include "kernel/yosys.h"
 #include "kernel/hashlib.h"
 #include "libs/sha1/sha1.h"
+#define CXXOPTS_VECTOR_DELIMITER '\0'
 #include "libs/cxxopts/include/cxxopts.hpp"
 #include <iostream>