Fatal error: Uncaught Error: Call to undefined function json_encode() in /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/functions.php:3877
Stack trace:
#0 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/widgets/class-wp-widget-text.php(58): wp_json_encode()
#1 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/class-wp-widget.php(252): WP_Widget_Text->_register_one()
#2 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/class-wp-widget-factory.php(102): WP_Widget->_register()
#3 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/class-wp-hook.php(287): WP_Widget_Factory->_register_widgets()
#4 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/class-wp-hook.php(311): WP_Hook->apply_filters()
#5 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/plugin.php(478): WP_Hook->do_action()
#6 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/widgets.php(1765): do_action()
#7 /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/class-wp-hook.php(287): wp_widgets_init()
#8 /var/www/home/denkyu.co.jp in /var/www/home/denkyu.co.jp/html/wordpress/wp-includes/functions.php on line 3877