Re: [boost] [timer] conflict between tools/inspect and libs/timer

Subject: Re: [boost] [timer] conflict between tools/inspect and libs/timer
From: Peter Dimov (lists_at_[hidden])
Date: 2013-12-28 08:50:32

Beman Dawes wrote:
> Critical changes on develop dating from February were never merged to 
> trunk, and I set the git merge point I missed them.

To avoid such (and other) surprises, what I did was ensure that develop and 
master are identical before doing the first merge.

    git diff --name-status master..develop

gave me an overview on where the two branches differ; the same command 
without --name-status goes into more detail.

(In principle, we all have kept our trunk and release branches in sync, so 
the above ought to have yielded nothing. In practice, however, all libraries 
likely had differences because (1) we sometimes forget to merge, (2) 
sometimes other people changed trunk and didn't merge and we didn't know, 
and (3) Stephen Kelly's Boost-wide changes were only on trunk.)

I then proceeded to identify the commits causing each change. I don't 
remember how exactly I did that, probably by using git log on the modified 
files and by looking at the commit history on Github.

After that, I applied each missing commit using git cherry-pick <sha>. That 
is, if a commit on develop was not present on master, I applied it to master 
with git cherry-pick; and if a commit on master was missing on develop 
(things like that do happen occasionally), I applied it on develop. I tried 
to do this in chronological order, which minimizes conflicts.

What made it more interesting for me is that I sometimes didn't want a 
commit to be part of the initial state, so I reverted it using git revert 
instead of applying it to the other branch using git cherry-pick; but this 
should probably not be needed most of the time.

The final result of all that cherry picking should be a state in which git 
diff master..develop doesn't report any differences. Once there, things are 
a simple "git merge" away.

It's probably too late now for all that explanation, but I already wrote it. 
:-)

> It may take a few days to figure out the best way to fix that.

The first thing I would try is git cherry-pick the missing commits into 
master.