Now I'm not so sure this is only a problem with my system.
If I build the Lunar image locally, I can use it normally and tests pass.
If I build the Mantic image locally (from this MP), I see the error I mentioned above.
I also tried building the images and running the tests on diglett, which doesn't use ZFS on the root partition. There, I see everything succeed (including the Mantic image).
So there's really some strange interaction going on between docker, ZFS and the Mantic image, but I haven't had the time to dig more into this problem. Either way, I believe it's worth spending a bit more time investigating things just to make sure that we're not shipping broken images out there.
Same comment from the squid MP applies here:
Now I'm not so sure this is only a problem with my system.
If I build the Lunar image locally, I can use it normally and tests pass.
If I build the Mantic image locally (from this MP), I see the error I mentioned above.
I also tried building the images and running the tests on diglett, which doesn't use ZFS on the root partition. There, I see everything succeed (including the Mantic image).
So there's really some strange interaction going on between docker, ZFS and the Mantic image, but I haven't had the time to dig more into this problem. Either way, I believe it's worth spending a bit more time investigating things just to make sure that we're not shipping broken images out there.