Lessons Learned From Porting LibreOffice's Build System To Meson

on YouTube ↗47m

" summary

Port of LibreOffice’s build moves a 5.8M+ line C++ tree off bespoke GNU Make onto Meson/Ninja by scraping verbose compiler invocations to reproduce flags, reimplementing code generators as Python to avoid native build-time binaries, and onboarding dependencies via wrapdb (about 18 external dependencies needed to build core on Windows). Surprises include multiple XML parsers (yes, awk appears) and subtle undefined-behavior bugs that only surface after switching; result compiles and needs iterative debugging and polishing rather than instant drop-in replacement.

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" chapters (34)

1. 0:00Intro
2. 0:32More than just LO
3. 1:26Why Meson?
4. 1:43Let's look at an example
5. 3:46Suppose you want to use Abseil C++ containers
6. 4:31WrapDB web service Make downloading dependencies as easy as possible but do not mandate its use
7. 6:19LibreOffice is BIG
8. 7:16One of the largest open source C++ code bases in the world
9. 8:43Changing build systems is a major engineering challenge
10. 10:03Hofstadter's law applied to change management
11. 10:27A real world example
12. 11:21The silver lining
13. 11:39A real world comment
14. 12:15Main skills needed
15. 13:28A typical vintage build pipeline
16. 13:58What about documentation?
17. 14:55The most important guideline on trying to understand how existing build setups have been implemented
18. 15:17A simple example
19. 16:11A more complicated example
20. 16:35What to do instead?
21. 16:51Practical steps to take • Run Make (or equivalent) in verbose mode
22. 17:47Same for configuration headers
23. 18:39Example from LibreOffice
24. 20:30Codegen fun
25. 22:15A portability thing to consider
26. 25:04External dependencies
27. 25:53For LibreOffice
28. 26:24Contrast this to many modern languages
29. 27:10Developer training
30. 27:29Splitting the work
31. 28:14Automation
32. 30:22A LibreOffice example
33. 32:12A Godot example
34. 34:18What have we learned?

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