I recently was nominated co-maintainer of this GPL library https://github.com/coq-community/corn
It does not use a copyright transfer agreement, historical authors are listed as copyright holders by their names at the beginning of each file, in the GPL license notice, as in this file https://github.com/coq-community/corn/blob/master/reals/Cesaro.v
My question is : must I ask permission to all these authors (there are 19) when I fix a bug, develop, or even delete parts of their code ?
This is a git repository so nothing is lost. Any user has access to all previous versions, knows exactly who wrote each line of code and when, so it looks in agreement with the modified works in the GPL :
For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.
It also looks compliant with section 5. Conveying Modified Source Versions.
It this interpretation of the GPL correct, or is this library frozen until the 19 of them give me written permission to modify their code ? This will never happen, some of them no longer respond about this project.
Edit: my modifications are not private. I plan to push them publicly in the github repo, so they will become the first version that people see when they open the repo.