diff --git a/compiler/erg_compiler/build_hir.rs b/compiler/erg_compiler/build_hir.rs
index 483037a4..9fd70929 100644
--- a/compiler/erg_compiler/build_hir.rs
+++ b/compiler/erg_compiler/build_hir.rs
@@ -51,7 +51,7 @@ impl Runnable for HIRBuilder {
 
     fn clear(&mut self) {
         self.lowerer.clear();
-        self.ownership_checker = OwnershipChecker::new(self.cfg().copy());
+        // don't initialize the ownership checker
     }
 
     fn exec(&mut self) -> Result<i32, Self::Errs> {
diff --git a/compiler/erg_compiler/ownercheck.rs b/compiler/erg_compiler/ownercheck.rs
index 2b10822c..872bfb60 100644
--- a/compiler/erg_compiler/ownercheck.rs
+++ b/compiler/erg_compiler/ownercheck.rs
@@ -3,11 +3,11 @@ use std::mem;
 use erg_common::config::ErgConfig;
 use erg_common::dict::Dict;
 use erg_common::error::Location;
-use erg_common::log;
 use erg_common::set::Set;
 use erg_common::traits::{Locational, Stream};
 use erg_common::vis::Visibility;
 use erg_common::Str;
+use erg_common::{impl_display_from_debug, log};
 use erg_parser::ast::{ParamPattern, VarName};
 use Visibility::*;
 
@@ -29,6 +29,8 @@ struct LocalVars {
     dropped_vars: Dict<Str, Location>,
 }
 
+impl_display_from_debug!(LocalVars);
+
 /// Check code ownership.
 /// for example:
 /// * Check if moved variables are not used again.