Now I'm confused, because you said all that you did was replace the symlink from a real directory to u:/ram, so I'd thought you were using the same tar version between these two tests ?
Yes, I'm a terrible tester. I used the old tar for the directory test and the new one for the ramdisk test.
I've attached the two patches I can see from an older tar.
Thanks! Now I see the situation is even funnier. The patches are actually unrelated to our MiNT problem, both of them are applied in 1.14 which is... broken (but in a different way, complaining about offests or what). Then 1.15 seems to be working OK (warnings about ownership but -- works). So the latest 1.2x contains a regression and/or feature which harms our poor FreeMiNT filesystem.