A question on pre-reqs for patch application

Hi there,

Recently we had an issue with pre-reqs for patch application.  Let's assume we have a patch and it needs a few pre-reqs.  Unfortunately those pre-reqs also need pre-pre-reqs, AND very unfortunately those pre-pre-reqs needs ...  you get the idea.  So where is the limits and what is the correct way to handle this kind of situation?

Thanks,

Ning