[Development] Qt modules, API changes and Qt 6

[Jedrzej Nowacki]

On Sunday, January 27, 2019 11:47:04 AM CET Harri Porten wrote:
> On Sat, 26 Jan 2019, Olivier Goffart wrote:
> > I think the "monorepo" is clearly a good approach. And git is evolving
> > with
> > shadow clones and partial checkout. LLVM/Clang recently choose the
> > monorepo
> > approach as it moves to git.
> > 
> > Of one problem is that this will make CI integration slower because each
> > CI
> > run now have to test both qtbase and qtdeclarative tests.
> 
> I've started to develop sympathy for "monorepos" during the last years. To
> counter often expressed fears like excessive build and test times one has
> to point out:
> 
> Bigger (or even single) repositories do NOT mean
> 
>    - monolithic builds and test runs
>    - monolithic packaging
> 
> Developers and packagers are free to model logical segements according to
> their needs.
> 
> Harri.

Hi,
 
  Personally, I also do like the idea of monolithic repo, while keeping 
modularization on the logical / build level. In our current state I see two 
major problems:
- our build is quite monolithic in practice. For example qtbase always needs 
to be build. CI currently caches builds on repository level (caches results of 
make install) with monolithic repository the optimization would need to be 
reconstructed on the build level. Conceptually it is good, but someone would 
need to do the work.
- as a consequence of a partial build, the repository may be in a broken 
state, for example not compiling. It can be solved by time based world 
rebuilding and tagging known good revisions, but some policies would need to 
be created.

Cheers,
  Jędrek