So all in all it seams as if there is a very old race condition here, which we "never" have seen yet. Moving the file to a different inode number fixes the test case, Git doesn't treat it as unchanged any more.Thanks a lot for investigating this! Would you mind posting the fix as patch?
That's ongoing. TC #3 and #4 are fixable, but #5 resists to be cured so far. I think we need a touch and sleep or so, more the next days (or weeks)
