The example included below "Why C and C++ Differ" is UB in both C and C++ (and says nothing about "why" C & C++ differ). The article isn't overall wrong but that bit is just...
(Feels a bit like LLM junk, but honestly not sure.)
I just watched video[0] that argues if you can consteval something, then it must be free of UB, which seems compelling, at least for these lower level helpers.
Unfortunately, it seems memcpy is not constexpr, so cannot be used like this, but std::bit_cast actually works[1] as constexpr, so I think in C++ that would now be the most preferred use. It won't allow the union either.
Despite the fact they're two different languages, people are often taught as though it's basically just a subset relationship and then they carry this through into the actual software they write.
Because neither of these are memory safe languages, you are required to ensure you've made no mistakes or else anything might happen.
(Feels a bit like LLM junk, but honestly not sure.)
Feels like LLM to me. I looked at some of the rest of the article and... pretty much certain now.
Shouldn't the code return 3 in the base case and 4 if the check for 2 was assumed to always hold ?
Unfortunately, it seems memcpy is not constexpr, so cannot be used like this, but std::bit_cast actually works[1] as constexpr, so I think in C++ that would now be the most preferred use. It won't allow the union either.
[0] https://www.youtube.com/watch?v=-LAXqqqX274 [1] https://godbolt.org/z/xGzjTMGvv
I can't downvote posts yet, but if you have the ability, consider it. This is clearly LLM slop without human review.
What's so genuine about this?
Because neither of these are memory safe languages, you are required to ensure you've made no mistakes or else anything might happen.
> and most blog posts on the topic get it wrong.
This smells like Claudism/LLMish.
https://stackoverflow.com/questions/53401654/why-was-stdbit-...
https://en.cppreference.com/cpp/language/reinterpret_cast
EDIT: If you’re able to use C++20 then clearly bit_cast is better.