How to fix "user warning: ... cache.inc on line 109." from a Drupal site?

The following message is shown on everything page of a Drupal开发者_JAVA百科 site:

"user warning: in /var/www/html/.../includes/cache.inc on line 109"

Please advise how to fix (get rid of) it. Thanks!

Info: User saw that after he deleted a post.

For the 'how to fix it' part of the question, we need more info on the error (full message, error log entries).

As for the 'get rid of it' part, you could (and should, if it's a production site) adjust the error reporting settings to 'Write errors to the log' under 'admin/settings/error-reporting' to prevent screen output of errors to site users.