由于php，奇怪的502 Bad Gateway错误

Question

奇怪的是，我的网站因为我在chrome.php上的php脚本错误导致502错误：

/ * index.php * /

include('code/include/langue.php');

/ * langue.php * /

if($l == 'en'){
    define("lg_slogan", "Discover and share Drum & Bass, Dubstep and Dub tracks.");
    define("lg_keywords", "drum&bass, drum, bass, drum & bass, dub, dubstep, break, breakbeat, electro, bass music, playlist, free");
    define("lg_name", "Name");
    define("lg_password", "Password");
    define("lg_keepSessionActive", "Keep me logged in");
    define("lg_login", "Login");
    define("lg_subscribe", "Subscribe");
...

}

else{   // français
    define("lg_slogan", "Découvrez et partagez des tracks Drum & Bass, Dubstep et Dub.");
    define("lg_keywords", "drum&bass, drum, bass, drum & bass, dub, dubstep, break, breakbeat, electro, bass music, playlist, gratuit");
    define("lg_name", "Nom");
    define("lg_password", "Mot de passe");
...

}

$const = get_defined_constants(true);

foreach($const['user'] as $key => $value){
    setcookie($key, $value, time()+14400);
}

当我在index.php中评论include时，502错误消失！

502错误是服务器错误，不是吗？