diff --git a/src/main/scala/leon/frontends/scalac/CodeExtraction.scala b/src/main/scala/leon/frontends/scalac/CodeExtraction.scala
index 0c81ec1d4f9a387355958f8700fabb8c4c55e43c..cc27bbc3b6c43418f40a065cdcba6ecfc984d374 100644
--- a/src/main/scala/leon/frontends/scalac/CodeExtraction.scala
+++ b/src/main/scala/leon/frontends/scalac/CodeExtraction.scala
@@ -1077,7 +1077,7 @@ trait CodeExtraction extends ASTExtractors {
 
           val closure = post.getType match {
             case BooleanType =>
-              val resId = FreshIdentifier("res", BooleanType).setPos(post).setOwner(currentFunDef)
+              val resId = FreshIdentifier("res", b.getType).setPos(post).setOwner(currentFunDef)
               Lambda(Seq(LeonValDef(resId)), post).setPos(post)
             case _ => post
           }