Re: Version control question.

[Ralf Baechle <ralf@linux-mips.org>]

On Fri, Aug 11, 2006 at 02:31:49PM -0700, Kaz Kylheku wrote:

> Is there any document that makes the linux-mips configuration management
> structure more obvious?

There is http://www.linux-mips.org/wiki/Git.  If that doesn't answer
your questions, let me know what you're missing and if I find the time
I'll add it.  Or just add it yourself to the wiki.

> I see that the 2.6.16 and 2.6.17 lines are in fact parallel branches, so
> that 2.6.16.27 is newer than 2.6.17.

Right.

> If something is broken in 2.6.17 but isn't in 2.6.16.27, what's the best
> way to find it?

You can use git bisect to do that on a clean that is unmodified tree:

$ git bisect start
$ git bisect bad linux-2.6.17
$ git bisect good linux-2.6.16.27

git will then checkout a tree that is about in the middle between the
good and bad version.  Build and test it, then either tell git

$ git bisect good

or

$ git bisect bad

depending on the outcome of your test.  Continue you've shurnk the
interval to a single version which is when git will tell you which
commit broke things.

Once you're finished you tell git to cleanup the tree from all the
bisecting stuff:

$ git bisect reset

> Just compare 2.6.16.27 to the closest parallel 2.6.17.x to see what the
> differences are?

git bisect is handy for finding a change even for relative beginners,
while starring at a diff is often much faster.  You can get a diff
between two tagged versions in git like:

$ git diff linux-2.6.16.27..linux-2.6.17

  Ralf