From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 15 Apr 2005 09:36:49 GMT
Subject: Re: Merge with git-pasky II.
Message-ID: <20050415093649.GA28077@elte.hu>
In-Reply-To: <1113556448.12012.269.camel@baythorne.infradead.org>


* David Woodhouse <dwmw2@infradead.org> wrote:

> Consider a simple repository which contains two files A and B. We 
> start off with the first version of each ('A1B1'), and the owner of 
> each file takes a branch and modifies their own file. There is 
> cross-pulling between the two, and then each modifies the _other's_ 
> file as well as their own...
> 
>    (A1B2)--(A2B2)--(A2'B3)
>     /  \   /            \
>    /    \ /              \
>  (A1B1)  X               (...)
>    \    / \              /
>     \  /   \            /
>    (A2B1)--(A2B2)--(A3B2')
> 
> Now, we're trying to merge the two branches. It appears that the most 
> useful common ancestor to use for a three-way merge of file A is the 
> version from tree 'A2B1', while the most useful common ancestor for 
> merging file B is that in 'A1B2'.

do such cases occur frequently? In the kernel at least it's not too 
typical. Would it be a problem to go for the simple solution of using 
(A1B1) as the common ancestor (based on the tree graph), and then to do 
a 3-way merge of all changes from that point on?

	Ingo