Authcache Caching Cancelled due to php error I have authcache installed on my Drupal site that runs on commerce(not Kickstart)

On all the page I am getting 

Cache Status: "Caching CANCELED"
Message 1: "Canceled: PHP Error: "


I enabled database logging but I don't see any additional information there. 

My pages are rendered properly and there is no errors being displayed on the page. So I am curious about the source of PHP Error that Authcache keeps referring to.
Ironically there is an error in the error-reporting code of Authcache 7.x-2.0-beta2. Apply the patch from issue #2161095, after that the PHP error message will be displayed correctly by the debug widget.