diff --git a/pack.c b/pack.c
index c91531f58d..a4e0882869 100644
--- a/pack.c
+++ b/pack.c
@@ -15,6 +15,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <float.h>
+#include "vm_core.h"
 #include "builtin.h"
 
 /*