Magento: Fatal error: Cannot override final method Mage_Core_Model_Abstract::clearInstance()

Fatal error: Cannot override final method Mage_Core_Model_Abstract::clearInstance() in app/code/core/Mage/Catalog/Model/Product.php on line 39

Mangeto报上面错误，很可能是apc配置问题。
找到apc.ini这个配置文件：

find / -name apc.ini

在该文件后面加一行：

apc.include_once_override=0