xdebug-fatalhandler.php

<?php
register_shutdown_function('handleShutdown');

function handleShutdown() {
    $lastError = error_get_last();

    if (null !== $lastError) {
        switch ($lastError['type']) {
            case E_ERROR:
            case E_PARSE:
            case E_CORE_ERROR:
            case E_CORE_WARNING:
            case E_COMPILE_ERROR:
            case E_COMPILE_WARNING:
                echo 'A fatal error occurred, stopping script execution';
                xdebug_break(); // This will trigger the debugger
                break;
        }
    }
}