Binary compatibility 100

on YouTube ↗01h 02m

" summary

Defines BC vs SC, shows concrete break examples (adding a defaulted arg breaks BC; adding an overload breaks SC when callers take addresses), and explains practical tools: removed API TU files plus CMake-generated macros to hide old symbols, PIMPL and reserved fields for layout, inline move via swap, and virtual hooks. Demonstrates a working, cross‑platform rolling binary compatibility window used in Qt, warns that wholesale exported classes and added virtuals remain the biggest blockers, and points to slides for code-level details.

AI-written summary · about

" chapters (10)

1. 0:00Introduction and scope
2. 2:34Motivating example
3. 6:57Defining compatibility
4. 13:35ABI and versions
5. 16:44Symbol visibility
6. 22:30Class exporting strategies
7. 27:00KDE BC resources
8. 31:24Core compatibility techniques
9. 40:23Cheating with binary compatibility
10. 49:42Q&A and advanced inlining

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