diff --git a/src/library/compiler/ir_interpreter.cpp b/src/library/compiler/ir_interpreter.cpp
index 90578a44e0a6..7c1b7d0ffc14 100644
--- a/src/library/compiler/ir_interpreter.cpp
+++ b/src/library/compiler/ir_interpreter.cpp
@@ -682,7 +682,7 @@ class interpreter {
                     break;
                 }
                 case fn_body_kind::Del: // delete object of unique reference
-                    lean_free_object(var(fn_body_del_var(b)).m_obj);
+                    lean_free_token(var(fn_body_del_var(b)).m_obj);
                     b = fn_body_del_cont(b);
                     break;
                 case fn_body_kind::MData: // metadata; no-op