Why PHP error reporting not working?

A user tries to enable PHP error reporting for PHP code troubleshooting. From the phpinfo.php page, seems the local values are correct.

display_errors On
display_startup_errors On
error_log php_error.log
error_reporting E_ALL

Create a test script test.php like the following:

<?php
echo zzzzzxzzzzxd('test');
?>

Since the faked function zzzzzxzzzzxd doesn't exit at all, it should trigger a fatal error when visiting http://youdomain.com/testing.php. However, there is no outputting any error on web browser, neither on the local VirtualHost PHP error logs.

What could be possibly wrong?

After checking the phpinfo page, we can see error_log global value showing as 32767 and local value showing as E_ALL. Further check the global php.ini, error_reporting = E_ALL. User has a local override in .htaccess as php_value error_reporting E_ALL.

The error reporting syntax in .htaccess php_value override is incorrect. If it is set in php.ini, it should be error_reporting = E_ALL, but if it is override in apache conf or .htaccess, error_reporting should be an integer instead of ASCII character. Such incorrect syntax will lead to 500 error for the site.

The corrrect override syntax should be:

php_value error_reporting 32767

Here 32767 in apache conf or .htaccess means E_ALL in php.ini. After the above change, php error reporting works fine and php fatal error shows in both browser and php error log.