<!DOCTYPE html>
<title>CSS Values and Units Test: attr</title>
<meta name="assert" content="Test attr use after free crash">
<link rel="help" href="https://crbug.com/365802556">
<head>
    <style>
        #div {
            --prop: attr(data-foo type(<ident>));
        }
    </style>
</head>
<body>
    <div id="div" data-foo="aaa123\aaa123aaa">Content</div>
</body>
<script>
    var elem = document.getElementById("div");
    getComputedStyle(elem).getPropertyValue("--prop");
</script>