On Sun, May 19, 2019 at 01:00:45PM -0700, Andrew Pinski wrote:
> On Sun, May 19, 2019 at 12:54 PM Segher Boessenkool
> <seg...@kernel.crashing.org> wrote:
> >
> > On Sun, May 19, 2019 at 03:21:01PM -0400, Marek Polacek wrote:
> > > On Sun, May 19, 2019 at 03:11:08AM -0500, Segher Boessenkool wrote:
> > > > On Sun, May 19, 2019 at 09:35:45AM +0200, Martin Liška wrote:
> > > > > Do we really need a commit integer numbers after the transition? I
> > > > > know
> > > > > we're used to it.
> > > > > But git commit hash provides that same.
> > > >
> > > > Revision numbers are nice short text strings, and from a revision number
> > > > you can see approximately when it happened, and from two revision
> > > > numbers
> > > > on the same branch you can trivially tell which one is older. Those are
> > > > nice features. But we can live without it, IMO.
> > >
> > > Since I do many bisections a day, losing this capability would be Very
> > > Bad.
> > > Without it, there's no range, and without a range, there's nothing to
> > > _bisect_.
> > >
> > > I bisect by hand, so if I have cc1plus.250000 (good) and cc1plus.260000
> > > (bad),
> > > I know the commit I'm looking for is within that range, and I can easily
> > > split
> > > the range, and it's at most log n steps. Whereas if we had e.g.
> > > cc1plus.de28b0
> > > and cc1plus.a9bd4d, I couldn't do it anymore.
> >
> > Git can bisect automatically just fine, there is no upside to doing things
> > manually. In git there are various handy ways of referring to commits; you
> > can say master@{3 days ago} for example, or zut@{31} to get the 31st
> > commit back on branch "zut", etc. See "man gitrevisions".
>
> Well one thing is if you have prebuilt cc1/cc1plus. So it is not
> really doing a manual bisect per-say but rather it is doing a manual
> bisect using prebuilt binaries and knowing which one comes before
> which one.
Exactly, we have many TBs of prebuilt binaries.
> One way is store the binaries based on the date that commit happened
> instead. This is a bit more complex but still doable.
Yeah, I guess we'll have to do something like that, then. :/
--
Marek Polacek • Red Hat, Inc. • 300 A St, Boston, MA
