Bootstrap add glyphicon to input box

<html>
<head>
<title>Bootstrap Grid</title>
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css">

<!-- Optional theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap-theme.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<!-- Latest compiled and minified JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/js/bootstrap.min.js"></script>

</head>
<body>
<form class="form-inline" role="form">
 <div class="form-group has-feedback has-feedback-left">
    <label class="control-label">Email</label>
    <input type="text" class="form-control">
    <i class="glyphicon glyphicon-envelope form-control-feedback"></i>
  </div>
</form>

</body>
</html>