current_user_can(‘manage_options’) causes white screen of death?

Setting display_errors to 1 has let me determine that for some reason wp-includes/pluggable.php was not included while running the plugin, so wp_get_current_user() function was missing. Although I didn’t find the reason of malfunction, thanks to answer to this question I hardcoded plugin by setting following at the beginning:

if(!function_exists('wp_get_current_user')) {
    include(ABSPATH . "wp-includes/pluggable.php");
}

Now everything works fine.