HTTP 500

A minha pagina está a devolver erro HTTP 500 e o debug dá estes pormenores:

Parse error: syntax error, unexpected 'if' (T_IF) in /home/x02v9k5h/casaavo.com/wp-includes/functions.php on line 8228

Fatal error: Uncaught Error: Call to undefined function wp_die() in /home/x02v9k5h/casaavo.com/wp-includes/class-wp-fatal-error-handler.php:233 Stack trace: #0 /home/x02v9k5h/casaavo.com/wp-includes/class-wp-fatal-error-handler.php(152): WP_Fatal_Error_Handler->display_default_error_template(Array, false) #1 /home/x02v9k5h/casaavo.com/wp-includes/class-wp-fatal-error-handler.php(57): WP_Fatal_Error_Handler->display_error_template(Array, false) #2 [internal function]: WP_Fatal_Error_Handler->handle() #3 {main} thrown in /home/x02v9k5h/casaavo.com/wp-includes/class-wp-fatal-error-handler.php on line 233

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