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. Developer is responsible for doing the cherrypicking
• 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 (5.6) Branch

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 make that more objective: 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.

Resulted in QUIP 5 (reviewed here)