diff --git a/src/main/scala/leon/purescala/PrettyPrinter.scala b/src/main/scala/leon/purescala/PrettyPrinter.scala
index cd1ac6709747585ae198e882dcd838e6d8d3ba76..89525002323d4093e961bc37476ad6d6e1299c5e 100644
--- a/src/main/scala/leon/purescala/PrettyPrinter.scala
+++ b/src/main/scala/leon/purescala/PrettyPrinter.scala
@@ -169,7 +169,7 @@ class PrettyPrinter(opts: PrinterOptions,
       case GenericValue(tp, id) => p"$tp#$id"
       case Tuple(exprs)         => p"($exprs)"
       case TupleSelect(t, i)    => p"$t._$i"
-      case NoTree(tpe)          => p"???[$tpe]"
+      case NoTree(tpe)          => p"<empty tree>[$tpe]"
       case Choose(pred)         => p"choose($pred)"
       case e @ Error(tpe, err)  => p"""error[$tpe]("$err")"""
       case AsInstanceOf(e, ct)  => p"""$e.asInstanceOf[$ct]"""
diff --git a/src/main/scala/leon/purescala/ScalaPrinter.scala b/src/main/scala/leon/purescala/ScalaPrinter.scala
index dc987ae49af6d26efb9c62b62dfd207c125e5f65..e030086b9ba4d0c73a3357878358ac58bb84f1fb 100644
--- a/src/main/scala/leon/purescala/ScalaPrinter.scala
+++ b/src/main/scala/leon/purescala/ScalaPrinter.scala
@@ -70,6 +70,8 @@ class ScalaPrinter(opts: PrinterOptions,
         p"""|forall(($args) =>
             |  $bd
             |)"""
+      case NoTree(tpe) =>
+        p"(_ : $tpe)"
       case _ =>
         super.pp(tree)
     }