C++ Under the Hood: Internal Class Mechanisms

on YouTube ↗58m

" summary

Concrete demos of how objects get built and torn down: vtable pointer setup during inside‑out construction and outside‑in destruction, and why destructors reassign vtables. Shows how member‑function pointers use compiler thunks for polymorphic dispatch and how member‑data pointers store offsets (null can be nonzero). Live code sketches implement a multicolumn sort using captured member‑data pointers, and a stack‑frame walkthrough explains base pointer links and backtraces on x86. Slides and working examples available; explanations are implementation‑level and practical.

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" chapters (19)

1. 0:00Introduction to C++ under the hood
2. 1:03Why internals matter
3. 3:13ISA vs HAS-A inheritance
4. 3:56Constructors, destructors, vtables
5. 9:19Destructing objects outside-in
6. 11:33Data and function pointers
7. 13:00Function pointers in C
8. 15:49C++ sort with function pointers
9. 16:30Member function pointers
10. 21:36Member data pointers
11. 23:47Null in C++
12. 27:20Sorting with member pointers & lambdas
13. 30:14Memory footprint & vtables
14. 38:56Stack frames & base pointers
15. 45:38Function return & cleanup
16. 46:00Q&A session part one
17. 50:15Q&A session part two
18. 53:51Q&A session part three
19. 55:44Q&A session part four

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