fix export * case

src/Module.js

@@ -233,6 +233,7 @@ export default class Module {
 			}
 
 			else if ( statement.isReexportDeclaration ) {
+				if ( statement.node.specifiers ) {
 					statement.node.specifiers.forEach( specifier => {
 						let reexport;
 
@@ -247,6 +248,7 @@ export default class Module {
 						addDependency( strongDependencies, reexport );
 					});
 				}
+			}
 
 			else {
 				keys( statement.stronglyDependsOn ).forEach( name => {