* arguments can be repeated without ill effect.
*/
List<JsName> requiredOrder = new ArrayList<JsName>();
for (int i = 0; i < arguments.size(); i++) {
JsExpression e = arguments.get(i);
JsParameter p = callee.getParameters().get(i);
if (isVolatile(program, e, callee)) {
requiredOrder.add(p.getName());
}
}
// This would indicate that isVolatile changed its output between
// the if statement and the loop.