Re: Moving to git

[Jeff Law <law at redhat dot com>]

On 08/24/2015 09:43 AM, Jakub Jelinek wrote:
> On Mon, Aug 24, 2015 at 09:34:41AM -0600, Jeff Law wrote:
> > On 08/24/2015 02:17 AM, Jakub Jelinek wrote:
> > > On Thu, Aug 20, 2015 at 04:09:39PM -0400, Jason Merrill wrote:
> > > > On 08/20/2015 02:23 PM, Jeff Law wrote:
> > > > > I suspect Jakub will strongly want to see some kind commit hook to
> > > > > associate something similar to an SVN id to each git commit to support
> > > > > his workflow where the SVN ids are  associated with the compiler
> > > > > binaries he keeps around for very fast bisection.  I think when we
> > > > > talked about it last year, he just needs an increasing # for each
> > > > > commit, presumably starting with whatever the last SVN ID is when we
> > > > > make the change.
> > > >
> > > > Jakub: How about using git bisect instead, and identify the compiler
> > > > binaries with the git commit sha1?
> > >
> > > That is really not useful.  While you speed it bisection somewhat by avoiding
> > > network traffic and communication with a server, there is still significant
> > > time spent on actually building the compiler.
> > I thought the suggestion was to use the git hash to identify the builds you
> > save.
> >
> > So you'd use git bisect merely to get the hash id.  Once you've got the git
> > hash, you can then use that to find the right cc1/cc1plus/f95 that you'd
> > previously built.
> >
> > It's not perfect (since you can't just look git hashes and know which one is
> > newer).
>
> But then you are forced to use git bisect all the time, because the hashes
> don't tell you anything.
True.

> Most often even before writing a script I try a couple of compiler versions
> by hand if I have some extra info (this used to work a 3 years ago, broke in
> the last couple of days, etc.).
A map of key hashes would probably be helpful with this kind of thing. 
Major releases, key branch->trunk merge points and the like.

It'd still be somewhat worse usability wise for you, but it ought to be 
manageable.

ANd like I said before, I'd support a git-hook which bumped some kind of 
index at each commit for your workflow.


> Perhaps I could touch the cc1.sha1hash files with timestamps corresponding to
> the date/time of the commit, and keep them sorted in some file manager by
> timestamps, still it would be worse usability wise.
> Not to mention we should keep the existing r123456 comments in bugzilla
> working, and I'm not convinced keeping a SVN version of the repository
> (frozen) for that purpose is the best idea.
I'd like to keep the old ones working, but new references should 
probably be using the hash id and commit name.

As for how to best keep the old r123456 links working, I don't know. 
Presumably those could be mapped behind the scenes to a git id.

Jeff