PHP Errors and Warnings

There’s no configuration option, as with WP_DEBUG set, WordPress sets the error reporting level to E_ALL & ~E_DEPRECATED & ~E_STRICT. This means all warnings and errors except strict errors and PHP deprecated functions (not WordPress ones) will be reported.

But note that you can disable the on-screen display, and log to a file instead. Please see https://wordpress.org/support/article/debugging-in-wordpress/

And, of course, you have PHP’s native error_log() function, the verbosity of which can be tweaked to your heart’s desire: https://www.php.net/manual/en/errorfunc.constants.php

If you really want to control the WP_DEBUG out level, you’d probably have to write a little mu-plugin.

UPDATE:

The WordPress debugging support article linked above has this on logging to file:

Note that this allows you to write to log file using PHP’s built in error_log() function, which can be useful for instance when debugging Ajax events.

So logging to file uses PHP’s built-in error_log() function — but I’m not sure if it’ll respect your server’s configured PHP error reporting level, or it’ll still use E_ALL & ~E_DEPRECATED & ~E_STRICT. (Alexa, add that to my weekend TO DOs 😀 )

• This reply was modified 3 years ago by George Appiah.