[Python-Dev] cpython (2.7): - Issue #17086: Backport the patches from the 3.3 branch to cross-build

[Antoine Pitrou]

Le Thu, 7 Feb 2013 20:02:39 +1000,
Nick Coghlan <ncoghlan at gmail.com> a écrit :
> On 7 Feb 2013 19:13, "Antoine Pitrou" <solipsis at pitrou.net> wrote:
> >
> > Le Wed, 6 Feb 2013 16:08:39 -0500,
> > Barry Warsaw <barry at python.org> a écrit :
> > > On Feb 06, 2013, at 02:38 PM, Antoine Pitrou wrote:
> > >
> > > >Le Mon, 04 Feb 2013 21:04:39 +0100,
> > > >Matthias Klose <doko at ubuntu.com> a écrit :
> > > >> So what I do understand, build-related issues like an arm64 or
> > > >> mingw32 port are ok for 2.7, if they are stable on the trunk,
> > > >> and communicated on python-dev?
> > > >
> > > >Making Python build on a new platform is, AFAICT, considered a
> > > >new feature, not a bugfix. For example, we support new MSVC
> > > >versions in the main development branch, not in bugfix branches.
> > >
> > > Except that 2.7 is an exception to that since it's the last of the
> > > Python 2 series, and has a much longer lifespan than normal
> > > releases.  I'm pretty sure we agreed that there would be some
> > > exceptions for issues like new platforms for 2.7.
> >
> > Well, apparently we didn't make such an exception for MSVC :-)
> 
> Python 2.7 still runs on Windows just fine, and changing the C
> runtime used is *not* purely a change to the build process (it
> effectively breaks the ABI).

There is a difference between supporting several MSVCs and changing the
MSVC used for the official binary builds. People did ask us to support
newer MSVCs.

> I'm not sure how you see that decision being remotely related to
> Benjamin's decision to allow the cross-compilation patches.

I was merely replying to the idea that "we allow new build features in
2.7". Non-trivial build patches have a tendency to produce unexpected
breakage (for the record, the initial cross-compiling commits on 3.x
brought a lot of breakage at first). Our build system is complicated
and *very* poorly documented, I am surprised you think it is a good
idea to accept large changes in bugfix releases.

I'm still of the advice that non-trivial build enhancements shouldn't be
treated differently from any new feature. Patches for bugfix branches
can be maintained externally, as they already are (e.g. by Linux
distributions).


(btw, nothing to do with this discussion, Nick, but it appears your
RHEL buildbot is offline)

Regards

Antoine.