Merging tags does not fast-forward with git 1.7.9

Merging tags does not fast-forward with git 1.7.9

[Domenico Andreoli]

Hi,

  with the recent changes in tag merging (I updated git to 1.7.9),
my usual "git merge v3.X-rcY" command does not fast-forward any more.
Of course the initial head is something like "v3.X-rcZ" without any
change so that it should (and usually did) fast-forward to the new head.

The editor is instead fired off and I have to fill the details of a
merge commit, diverging from mainline as soon as I save and exit.

Is there any simple and clear explanation for this? Thank you.

cheers,
Domenico

ps: I admit I didn't follow the details about tag signatures so probably
I missed something that I shouldn't.

Re: Merging tags does not fast-forward with git 1.7.9

[Dan Johnson]

On Thu, Feb 9, 2012 at 4:54 AM, Domenico Andreoli <cavokz@gmail.com> wrote:
> Hi,
>
>  with the recent changes in tag merging (I updated git to 1.7.9),
> my usual "git merge v3.X-rcY" command does not fast-forward any more.
> Of course the initial head is something like "v3.X-rcZ" without any
> change so that it should (and usually did) fast-forward to the new head.
>
> The editor is instead fired off and I have to fill the details of a
> merge commit, diverging from mainline as soon as I save and exit.
>
> Is there any simple and clear explanation for this? Thank you.

Someone else can explain what is going on more fully, but can you
report what happens when you run "git merge --ff-only v3.X-rcY"?

-- 
-Dan

Re: Merging tags does not fast-forward with git 1.7.9

[Domenico Andreoli]

On Thu, Feb 09, 2012 at 10:50:50AM -0500, Dan Johnson wrote:
> On Thu, Feb 9, 2012 at 4:54 AM, Domenico Andreoli <cavokz@gmail.com> wrote:
> >
> >   with the recent changes in tag merging (I updated git to 1.7.9),
> > my usual "git merge v3.X-rcY" command does not fast-forward any more.
> > Of course the initial head is something like "v3.X-rcZ" without any
> > change so that it should (and usually did) fast-forward to the new head.
> >
> > The editor is instead fired off and I have to fill the details of a
> > merge commit, diverging from mainline as soon as I save and exit.
> >
> > Is there any simple and clear explanation for this? Thank you.
> 
> Someone else can explain what is going on more fully, but can you
> report what happens when you run "git merge --ff-only v3.X-rcY"?

This is Debian unstable, out-of-the-box git package 1.7.9-1.

$ git reset --hard v3.3-rc2
HEAD is now at 62aa2b5 Linux 3.3-rc2
$ git merge --ff-only v3.3-rc3
fatal: Not possible to fast-forward, aborting.
$ 

Same for v3.3-rc1 -> v3.3-rc2.

Thanks,
Domenico

Re: Merging tags does not fast-forward with git 1.7.9

[Andreas Schwab]

Domenico Andreoli <cavokz@gmail.com> writes:

> This is Debian unstable, out-of-the-box git package 1.7.9-1.
>
> $ git reset --hard v3.3-rc2
> HEAD is now at 62aa2b5 Linux 3.3-rc2
> $ git merge --ff-only v3.3-rc3
> fatal: Not possible to fast-forward, aborting.
> $ 

Workaround:

$ git merge v3.3-rc3^{}
Updating 62aa2b5..d65b4e9
Fast-forward

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Merging tags does not fast-forward with git 1.7.9

[Carlos Martín Nieto]

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On Thu, 2012-02-09 at 10:54 +0100, Domenico Andreoli wrote:
> Hi,
> 
>   with the recent changes in tag merging (I updated git to 1.7.9),
> my usual "git merge v3.X-rcY" command does not fast-forward any more.
> Of course the initial head is something like "v3.X-rcZ" without any
> change so that it should (and usually did) fast-forward to the new head.
> 
> The editor is instead fired off and I have to fill the details of a
> merge commit, diverging from mainline as soon as I save and exit.
> 
> Is there any simple and clear explanation for this? Thank you.
> 
> cheers,
> Domenico
> 
> ps: I admit I didn't follow the details about tag signatures so probably
> I missed something that I shouldn't.

This was discussed recently

http://thread.gmane.org/gmane.comp.version-control.git/189825



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Re: Merging tags does not fast-forward with git 1.7.9

[Domenico Andreoli]

On Thu, Feb 09, 2012 at 05:06:41PM +0100, Carlos Martín Nieto wrote:
> On Thu, 2012-02-09 at 10:54 +0100, Domenico Andreoli wrote:
> > Hi,
> > 
> >   with the recent changes in tag merging (I updated git to 1.7.9),
> > my usual "git merge v3.X-rcY" command does not fast-forward any more.
> > Of course the initial head is something like "v3.X-rcZ" without any
> > change so that it should (and usually did) fast-forward to the new head.
> > 
> > The editor is instead fired off and I have to fill the details of a
> > merge commit, diverging from mainline as soon as I save and exit.
> > 
> > Is there any simple and clear explanation for this? Thank you.
> > 
> > cheers,
> > Domenico
> > 
> > ps: I admit I didn't follow the details about tag signatures so probably
> > I missed something that I shouldn't.
> 
> This was discussed recently
> 
> http://thread.gmane.org/gmane.comp.version-control.git/189825

The command I was looking for is:

  $ git merge --ff-only v3.X-rcY^0

thanks,
Domenico

Re: Merging tags does not fast-forward with git 1.7.9

[Junio C Hamano]

Domenico Andreoli <cavokz@gmail.com> writes:

>   with the recent changes in tag merging (I updated git to 1.7.9),
> my usual "git merge v3.X-rcY" command does not fast-forward any more.

Making "merge $tag" always record the signed tag information was the whole
point of the change in 1.7.9, so asking to merge a tag will *not* fast
forward by default anymore.  "git merge v3.X-rcY^0" is a usable workaround
in the meantime; we are also cooking a fix for a typical case where you
ask for "git merge --ff-only v3.X-rcY" explicitly. This errored out
incorrectly, which was discovered and fixed early this week and is cooking
in the 'next' branch. We would like to push it out as part of 1.7.9.1, and
we would need help testing it. The more people test it sooner, the likelier
people will see more solid 1.7.9.1 release sooner.

> The editor is instead fired off and I have to fill the details of a
> merge commit, diverging from mainline as soon as I save and exit.

Yes, that "diverging from mainline" is really bad, and that is why we need
the fix to honor "--ff-only" (which is the way to make sure you do not
diverge) tested quicly so that we can push 1.7.9.1 out.

Thanks.