diff --git a/gomock/controller.go b/gomock/controller.go
index 72a59db..528944c 100644
--- a/gomock/controller.go
+++ b/gomock/controller.go
@@ -19,6 +19,7 @@ import (
 	"fmt"
 	"reflect"
 	"runtime"
+	"runtime/debug"
 	"sync"
 )