How to use `update-file-autoloads'

[Klaus-Dieter Bauer]

Hello!

I have been trying to figure out the use of `update-file-autoloads', but I
cannot seem to find out how it works. Regardless of whether I pass it a
relative or an absolute file name, it will pass the absolute file name to
`autoload-file-load-name' which then enters and endless-loop (which I
confirmed to happen in the Cygwin version as well). The loop

    (while name
      (setq name (directory-file-name name))
      (push (file-name-nondirectory name) names)
      (setq name (file-name-directory name)))

will never finish, because (file-name-directory "/") evaluates to "/", thus
`name' never becomes nil. Run from the native Windows version the
corresponding behaviour is (file-name-directory "c:/") => "c:/".

Am I using `update-file-autoloads' wrong or is this a bug? Since I believe,
that a bug in `autoload.el' would quickly be noticed while building emacs
normally, I assume the first, which is why I did not want to send this as a
bug-report right away.

- Klaus