From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH 3/3] builtin/checkout: DWIM with -f -b
Date: Sun, 20 Jun 2010 17:16:05 -0400
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To: Junio C Hamano <gitster@pobox.com>
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On Sun, Jun 20, 2010 at 02:10:32PM -0700, Junio C Hamano wrote:

> FWIW, I often end up doing this when rebuilding 'pu' (and 'jch' that is
> used internally that keeps a version of 'next' with cleaner history).
> 
>     ... a script to regenerate jch on top of master (and pu on jch)
>     $ Meta/Reintegrate master..jch >Meta/redo-jch.sh
>     $ Meta/Reintegrate jch..pu >Meta/redo-pu.sh
> 
>     ... rewind and rebuild jch on top of updated master
>     $ git checkout -f -b jch master
>     ... error ... oops
>     $ git branch -f jch master
>     $ git checkout jch
>     $ Meta/redo-jch.sh
>     $ git diff next
>     ... no output---good.

I'm certainly sympathetic, but as I understand it, with this new patch
you are doing the equivalent of:

  git branch -f jch master
  git checkout -f jch

which is different than what you wrote above.  For your workflow, I
doubt it matters, but it is potentially destructive.

-Peff