diff --git a/src/buffered-process.coffee b/src/buffered-process.coffee
index 8ca9f7d8b..24638082e 100644
--- a/src/buffered-process.coffee
+++ b/src/buffered-process.coffee
@@ -154,3 +154,5 @@ class BufferedProcess
       @killOnWindows()
     else
       @killProcess()
+
+    undefined