diff --git a/lib/ace/mode/css_worker.js b/lib/ace/mode/css_worker.js
index e5ef2eb1..20a4c5e1 100644
--- a/lib/ace/mode/css_worker.js
+++ b/lib/ace/mode/css_worker.js
@@ -76,6 +76,8 @@ oop.inherits(Worker, Mirror);
 
     this.onUpdate = function() {
         var value = this.doc.getValue();
+        if (!value)
+            return this.sender.emit("csslint", []);
         var infoRules = this.infoRules;
 
         var result = CSSLint.verify(value, this.ruleset);