diff --git a/.travis.yml b/.travis.yml
index b2ced15..9a48e0b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -153,4 +153,5 @@ script:
 after_script:
   - echo "Standard Output: $(cat stdout.txt)"
   - echo "Standard Error : $(cat stderr.txt)"
+  - [ "0" = "$(wl -l stderr.txt)" ] || exit 2