diff --git a/basis/listener/listener.factor b/basis/listener/listener.factor
index d96e0df6c1..68777f2f73 100644
--- a/basis/listener/listener.factor
+++ b/basis/listener/listener.factor
@@ -62,6 +62,8 @@ SYMBOL: max-stack-items
 
 SYMBOL: error-summary?
 
+t error-summary? set-global
+
 <PRIVATE
 
 : title. ( string -- )