Greg,

I will not respond point by point, but the message here is: "CMake support is available and believed to be in good shape into master based on our manual tests and initial CI configuration exercising it, it will replace autotools+nmake soon, be ready for it and help polishing it". There will perhaps be areas where it will not do everything that existing build systems made, but existing build systems have also their flows that are not easily fixable. So be it. Having one single build system at the end of the process, and used in an idiomatic way (our autoconf system without automake is far from being idiomatic), is the main objective of this whole effort from my side.

CMake might not be completely ready for 3.5.0 for all imaginable platforms & configurations (we don't promise to support all platforms anyway. I don't believe we have a formal list of supported platforms by the way. I'd say what is tested on our CI is the practical definition of what is supported), and we won't defer indefinitely 3.5.0 if it doesn't work on some confs. That's why autoconf&nmake will only be removed in 3.6.0, and we have 3.5.x point releases to help address issues.

The release process  is described in HOWTO-RELEASE and it points to the mkgdaldist.sh script

You can generate a gdal-master.tar.gz with:

./mkgdaldist.sh master -branch master

No idea if the script works properly on non-Linux systems. You'll need some prerequisites for the script to run: Sphinx (pip install -r doc/requirements.txt) to generate man pages, swig

Or just clone the git repo and rm -rf autotest .git .github, and that will be very close to the final tarball, at least for the purpose of doing a CMake build

and try packaging this.

Even


Le 18/01/2022 à 14:06, Greg Troxel a écrit :
Even Rouault <even.roua...@spatialys.com> writes:

The new CMake build system
(https://gdal.org/development/rfc/rfc84_cmake.html) has made excellent
progress, and I believe that it should be in a production ready state
on time for GDAL 3.5.0 (~ May). It is already very close to it
according to a checklist I had created
(https://docs.google.com/spreadsheets/d/1SsUXiZxKim6jhLjlJFCRs1zwMvNpbJbBMB6yl0ms01c).
Do you mean that the master branch already has cmake support that you
believe 99% meets the requirements?

I think that establishing a date before the code meets requirement risks
a later decision to proceed anyway despite meeting the requirements.  So
I'd like to flip this around to the steps needed, with the autoconf
removal decision gated on packager testing.

Specifically:

   - Get master in a shape where the developers believe the requirements
     are met.  This includes build instructions, specifically about how
     to get the right RPATH behavior.  It's going to need testing
     building to a prefix other than /usr and specifically a prefix not
     in the default linker search path.

     I'm unclear on the plan for the test suite.  If running py-test in
     the tests directory against an installed build still works, that's
     fine -- I don't see a need to couple test improvements with the
     cmake conversion.

   - Produce an alpha tarball, following the same (documented) procedure
     that would be used for a relaase in an autoconf-removed world.  This
     is what packagers package, and users hand build.  Tarball creation
     should be documented and scripted, so this should be a combination
     of good testing and near-zero effort.

   - Call for packager and user testing of the alpha tarball.  Give them
     1 full month, because converting a packaging build from autoconf to
     cmake is not trivial, and because everything that depends on gdal
     needs testing too.  (In my case, the gdal build control files are
     much bigger than typical packages.)

     I expect to find problems, because I usually do on autoconf->cmake
     transitions, and often around RPATH handling.  But I will be happy
     to report 100% success if that's how it is.  And I'll try to do this
     sooner rather than later.

   - If there are any failures to meet requirements (including on systems
     where gdal does not have CI; that's the point of the call for
     testing), fix and release another alpha.  2 weeks is adequate
     testing time, if the failures were minor enough to not prevent
     getting to a working state.

   - Once the report/fix cycle ends, then the autoconf removal can
     proceed.

The above can be pipelined, if an alpha tarball can be produced that
90-95% meets requirements, enough that it's reasonable to do a draft
packaging conversion and end up with an installed gdal that one can
build a working qgis against.

Will this work for May?  I don't know, and I think the big questions are
when a believed-requirements-meeting alpha tarball can be produced, and
how many residual issues there are.  With a alpha in 2 weeks, the odds
are good.  With an alpha on April 1, I don't see how it can work.

Greg

--
http://www.spatialys.com
My software is free, but my time generally not.

_______________________________________________
gdal-dev mailing list
gdal-dev@lists.osgeo.org
https://lists.osgeo.org/mailman/listinfo/gdal-dev

Reply via email to