diff --git a/waroot/waroot.go b/waroot/waroot.go
index a5df45dd544da68783b3ba1371e3aac73fb3ca11..ac687e8e8be156a0169b6250c07817aa38fcc0b3 100644
--- a/waroot/waroot.go
+++ b/waroot/waroot.go
@@ -118,6 +118,7 @@ var stdPkgs = []string{
 	"image/color/palette",
 	"io",
 	"math",
+	"math/big",
 	"math/bits",
 	"os",
 	"reflect",