From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: [PATCH] add receive.denyNonFastforwards config variable
Date: Wed, 20 Sep 2006 23:43:29 -0700
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To: Jeff King <peff@peff.net>
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	message of "Thu, 21 Sep 2006 01:52:53 -0400")
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Jeff King <peff@peff.net> writes:

>>     X - a - b - c - Y
>>   /           /
>> o - d - e - f
>
> In your example, git-merge-base X Y returns X. In fact, I could only get
> one merge base out of git-merge-base --all. I tried looking in the tests
> to find a case that produced multiple merge bases, but I was unable to
> find one. Is there an example floating around somewhere?

There are quite a few in git.git itself.  In the recent history,
this counts 42, the answer to everything.

#!/bin/sh
LF='
'
git rev-list --parents master..next |
while read it p1 p2 octo
do
	case "$p2" in '') continue ;; esac
        mb=`git merge-base --all "$p1" "$p2"`
	case "$mb" in ?*"$LF"?*) echo "$p1 $p2" : $mb ;;
        esac
done