QtCS2016 Managing Qt Branches

Managing Qt's Branches

Number of existing branches (5.6LTS, 5.7.,5.8 dev) causes a number of problems

• Strain on COIN which also has release branches
• Merging becomes increasingly difficult
• Hard to manage for individual developers

Branches

• Close 5.7 after 5.7.1. We then have LTS, stable, dev.
• After 5.7 is closed and sanity bot is upgraded (to handle cherry-picking), go into cherrypicking mode for 5.6
• Cherry-picking technicalities need to be figured out: Let sanity bot verify source ("cherrypicked from") the SHA1
• In the future, exact time for closing stable branches will be discussed for each one individually

Submit Policy

Target which branch?

• Long Term Support:

Initially equal to stable, increasingly strict over time: Fix only severe issues, avoid regressions.

* Bugs: For example, P2 for the first year, P1 for year 2, rest Security. Try to further objectify that: Jedrzei + Friedemann
* Tests: Fix/stabilize tests itself, add tests
* No performance improvements unless really significant (relevant/reduces O(n))
* Upgrading 3rd party (including WebEngine) 
* Support new OS versions unless introducing new platforms, no rewrite of QPA
* No cleanups, positively: -> dev

To aid customers with issues, patches for issues in LTS to be locally applied can be provided, but the fixes will be pushed to higher versions of Qt.