fix: bug at toLCNF

src/Lean/Compiler/LCNF.lean

@@ -440,7 +440,7 @@ where
         visitLet body (xs.push value)
       else
         let type' ← liftMetaM <| toLCNFType type
-        let value' ← visitChild value
+        let value' ← visit value
         let x ← mkLetDecl binderName type value type' value'
         visitLet body (xs.push x)
     | _ =>

tests/lean/run/lcnf2.lean

@@ -33,3 +33,10 @@ noncomputable abbrev TupleN : (n : Fin 1) → TupleNTyp n.val
 
 set_option pp.proofs true
 #eval Compiler.compile #[``TupleN]
+
+
+def userControlled (a b : Nat) :=
+  let f := fun _ => a
+  f () + b
+
+#eval Compiler.compile #[``userControlled]