[gentoo-portage-dev] version management for eclasses

[Amit Dor-Shifer]

I've been through the list, and also read GLEP #33, in search for 
recommended practices regarding eclasses. 

the way I understand it, when an eclass is modified to accomodate a new 
ebuild, old ebuilds are broken. Specifically, downgrading with those 
broken ebuilds is no longer possible, as the eclass code they used to 
execute is no longer available.

So, basically, downgrade is possible only while dependent eclasses 
haven't changed. And AFAIK, portage doesn't test whether inherited 
eclasses were modified since the ebuild was signed. This means that 
there's also no traceability: old ebuilds cannot say "When I was in 
business, my inherited eclass was THIS".

I'm wondering how do others address the downgrade issue.

Thanks,
Amit