Potentially dangerous behavior of git gc

Hi,

I encountered an issue with git gc.

Consider the following scenario. Repo A is using repo B as an alternate object database through the .git/objects/info/alternates mechanism. B is at /some_path/B. A has some references, including HEAD that are pointing at objects that are in fact in the object database of B.

For some reasons, paths are modified on the machine, so that B gets moved at /some_new_path/B.

Obviously A cannot find its objects anymore and its alternate info should be updated.

Suppose that now one runs git gc on A.

Correctly git gc complains about the broken alternate link. And then complains again as it cannot find some objects.

However, rather than trying to preserve the repo integrity, it then _removes_ all the references pointing to non existing objects.

With this when the alternate info of A is finally updated, A is broken, missing many references and not having a head anymore.

Would it be better to have git gc not to take dangerous actions on potentially problematic repos?

Thanks

Sergio