Const vs. constexpr vs. consteval vs. constinit in C++20

Re:Const vs. constexpr vs. consteval vs. constinit in C++20 by JonChesterfield on Tuesday November 29, 2022 @08:30AM (#33787306)

I thought the C11 memory model was considered correct, possibly modulo 'consume' which seems to be ignored. The implementation in terms of types instead of operations has a performance cost but otherwise works. What glaring flaws do you have in mind?

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Re:Const vs. constexpr vs. consteval vs. constinit in C++20 by cyber_kinetist on Tuesday November 29, 2022 @12:10PM (#33790221)

Well, not exactly “glaring” (unless you are a PL expert), but for instance there’s a paper that was referenced in that Rustonomicon link:

https://fzn.fr/readings/c11comp.pdf

And also

https://plv.mpi-sws.org/scfix/paper.pdf

Though maybe these issues were fixed in C++20 (which I only learned till recently that they’ve revised their memory model there!)

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Re:Const vs. constexpr vs. consteval vs. constinit in C++20 by JonChesterfield on Tuesday November 29, 2022 @07:23PM (#33795289)

Nice references. Going to take me a while to make sense of them. A superficial interpretation is one says relaxed doesn't work and the other says sequentially consistent doesn't work. Not great news tbh, hopefully it'll look better on closer examination.

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