我在切换wp_debug后得到这个
Notice: Undefined index: enabled in /home/bhrmwgng/public_html/metasyfe.com/wp-content/plugins/above-the-fold-optimization/includes/localizejs.class.php on line 123
Warning: Cannot modify header information - headers already sent by (output started at /home/bhrmwgng/public_html/metasyfe.com/wp-content/plugins/above-the-fold-optimization/includes/localizejs.class.php:123) in /home/bhrmwgng/public_html/metasyfe.com/wp-includes/pluggable.php on line 1207
从WordPress 2.5版本开始，将WP_DEBUG设置为true也会将错误报告级别提高到E_ALL，并在使用弃用的函数或文件时激活警告;否则，WordPress将错误报告级别设置为E_ALL ^ E_NOTICE ^ E_USER_NOTICE。
这会导致这些不是错误的消息，显示Notice和Warning级别。
见:http://php.net/manual/es/function.error-reporting.php