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From: Spiros Bousbouras <spibou@gmail.com>
Newsgroups: comp.compilers
Subject: Re: binary search debugging of compilers
Date: Thu, 18 May 2023 10:50:24 -0000 (UTC)
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On Wed, 17 May 2023 10:55:27 -0400
Russ Cox <rsc@swtch.com> wrote:
> When BitKeeper came along, we added this:
>
>        --longest        Restrict  the  deltas  to  those  on  the longest line
>                         between the two range endpoints.  Unlike a range, the
>                         lower bound is included in the output.
>
> because BitKeeper history is a lattice, not a straight line.  So your
> test points became
>
>         bk changes -nd:REV: > REVS
>
> and binary search over those.  That gets you the longest "straight" line
> in the graph.

Any partial ordering can be extended to a total ordering. Why can't you
just do that instead of using  'the longest "straight" line' ?