Deprecating volatile

on YouTube ↗01h 01m

" summary

Argues for deprecating many volatile uses in C and C++, documents actual edits accepted for C++20 (language and library papers split), shows LLVM semantics where volatility is an instruction property not a type property, and gives concrete examples that will appear in the standard (volatile bitfields, unions, structured bindings). Proposes deprecated volatile compound assignments and removing top-level volatile qualifiers, plans a replacement that treats volatile as instruction property and notes which changes land in C++20 versus those deferred.

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" chapters (47)

1. 0:00Introduction
2. 1:05How did this get started
3. 4:13Motivation examples
4. 4:30Example
5. 8:45What does it do
6. 10:15Another example
7. 10:54Toplevel volatile qualified
8. 12:42Constructor volatile
9. 13:16Load volatile
10. 14:36What does volatile mean
11. 15:01Knowing your own ignorance
12. 15:12Volatile optimizer
13. 16:06Memory can tear
14. 17:03Is it guarantees instruction ordering
15. 17:57Is it guarantees synchronization
16. 18:55Early unix
17. 19:05Early C
18. 22:13Volatile
19. 25:43Documentation
20. 26:42Models
21. 27:07Variables
22. 28:53Semantic similarities
23. 29:26Threads
24. 29:55Atomicity
25. 30:11Standards
26. 30:31Poetry
27. 31:09Abstract
28. 38:21What do compilers do
29. 39:44What do optimizers do
30. 40:48Target specific semantics
31. 41:16Side effects of volatile operations
32. 41:34Explicit dereferencing
33. 43:01CV
34. 43:31Corner cases
35. 44:26Do not break good code
36. 45:00Remove confusion
37. 45:16Remove useless abstractions
38. 45:34No replacement for volatile
39. 46:05Remove complexity from the language
40. 46:35Make volatile useful
41. 48:51Remove truly useless
42. 49:10Remove cons
43. 49:46Volatile load and volatile stores
44. 52:13Structured bindings
45. 53:20Final paper
46. 53:35National body
47. 54:00Examples

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