diff --git a/src/main/scala/leon/purescala/PrettyPrinter.scala b/src/main/scala/leon/purescala/PrettyPrinter.scala
index a7ead369a606ce2fb51d82de4097cbfc723bfa73..32a56fcfcc9c483bf46f88534b34a3a6c968a950 100644
--- a/src/main/scala/leon/purescala/PrettyPrinter.scala
+++ b/src/main/scala/leon/purescala/PrettyPrinter.scala
@@ -527,7 +527,7 @@ class PrettyPrinter(opts: PrinterOptions,
             p"  $b"
 
           case None =>
-            p"???"
+            p"  ???"
         }
 
         p"""|