I have an extension that is giving me an endless loop, and I can't figure out the cause. I tried to follow this (Fundamentals for debugging a Magento store) but can't understand how to do it ? Can anyone help me ?
Your question is a little broad, but in general.
Figure out which controller and action method corresponds to the URL that triggers an endless loop
Look at the controller action and figure out how it is calling code in your extension
Add a series of
exit(__FILE__ . '::' . __LINE__);lines until you pinpoint the section of code that's an endless loop.