diff --git a/src/Bundle.js b/src/Bundle.js
index 92efc0b..0334611 100644
--- a/src/Bundle.js
+++ b/src/Bundle.js
@@ -207,7 +207,7 @@ export default class Bundle {
 
 		this.orderedModules.forEach( module => {
 			module.reassignments.forEach( name => {
-				isReassignedVarDeclaration[ module.exports.lookup( name ) ] = true;
+				isReassignedVarDeclaration[ module.locals.lookup( name ).name ] = true;
 			});
 		});
 
diff --git a/src/Module.js b/src/Module.js
index e7a7ec1..e526c52 100644
--- a/src/Module.js
+++ b/src/Module.js
@@ -279,10 +279,6 @@ export default class Module {
 					}
 				});
 			});
-
-			keys( statement.modifies ).forEach( name => {
-				( this.modifications[ name ] || ( this.modifications[ name ] = [] ) ).push( statement );
-			});
 		});
 
 		// discover variables that are reassigned inside function