--root seems to cancel out --keep-empty in git-rebase

As the subject says, these two commands give identical behaviour:

	git rebase --interactive --keep-empty --root

and:

	git rebase --interactive --root

I.e. --keep-empty has no effect when --root is specified.

Ideas for workaround welcome.

Regards
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Pierre Ossman           Software Development
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A: Because it messes up the order in which people normally read text.
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