[Development] QtCS2019 Notes from "Branch Policy" discussion

[Filippo Cucchetto]

> Sounds nice, but the reality is that this has not been the case.
> Forward-merging hasn't worked without a fair bit of hand-holding; one big
> difference is that forward-merging is a centralized process, so the
> hand-holidng had to be done by the merge master who has nothing to do with
> either the code that’s being modified, or the patch that caused conflicts.
> And nobody wants to be the merge-master.
>
> And who does backwad merges? the CI automatically? Indeed backward merges
don't suffer for conflicts

Also (as people confirmed during the discussion at CS) the forward merging
> process causes significant delays. Fixing a bug in 5.15 that you would like
> to modify to use modern C++, or refactor whatever smelly code you might
> have run into, in dev means that you spend weeks on a simple bug fix;
> merging it into 5.15; waiting for forward merging (and potentially
> integrations) to succeed; adjusting the merged change in dev; merging into
> dev.
>
I don't get this one because even if you push your fix directly to dev you
still need to test your fix in previous branches. Furthermore if your fix
used a modern C++ syntax chances are that you cannot backport to previous
branches. Thus you still need to code the fix for 5.15 C++ syntax, test it
in dev, test it in 5.15, integrate in both and then eventually make another
commit on dev for porting your fix to new modern c++ syntax.
Supposing to have a bot for auto forward merges (as i understood you're
supposing to have for backward merges) i don't see any difference.


> This kills the motivation to do necessary refacorings and structural code
> improvements, which is not good for the project.
>
Probably. At the same time i've the fear that might increase sloppyness in
backporting.


>
>
> Cheers,
> Volker
>
>
Thank you for the explanations

-- 
Filippo Cucchetto
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