Re: [Gnu-arch-users] tla undo feature request

[Tom Lord]

    > From: Robert Collins <address@hidden>
    >> It's fairly trivial.

    >> The big thing is that when comparing signatures for equality you have
    >> to be prepared for one of them to have mode info and the other not to.
    >> In that case, you have to compare them while ignoring the mode info.

    >> Should be, like, an O(10) line patch

    > And there should be similar things already - the dev_t and some other
    > thing we excluded from the signatures way back when.

It's not quite the same as the dev_t and ctime cases which is why I
didn't put this in when fixing rwa's thing.   With those, you're just
stripping a field out of some old inode sigs, after which they look
exactly (bitwise) like current inode sigs.   With modes, you've got 
old inode sigs that lack the field and you need to compare them
against sigatures that have them.

I've been assuming that having people _not_ have to rebuild old
revlibs was desirable here.   Of course, that leaves some old
revisions at slight risk.

The alternative would be to just put in modes and let people have to
rebuild old revlibs and project trees.

-t