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Everything in C is undefined behavior

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Re: Everything in C is undefined behavior

#11
post #9

Anyone who uses the construction "C/C++" doesn't write modern C++, and probably isn't very familiar with the recent revisions despite TFA's claims of writing it every day for decades. Far from being just "C with classes", modern C++ is very different than C. The language is huge and complex, for sure, but nobody is forced to use all of it. No HN comment can possibly cover all the use cases of C++ but in general, unle…

> the upshot is you never need to deal with the Rust community In the end, everything comes down to culture war.

Perhaps we should rewrite our culture in Rust.

Re: Everything in C is undefined behavior

#14

Anyone who uses the construction "C/C++" doesn't write modern C++, and probably isn't very familiar with the recent revisions despite TFA's claims of writing it every day for decades. Far from being just "C with classes", modern C++ is very different than C. The language is huge and complex, for sure, but nobody is forced to use all of it. No HN comment can possibly cover all the use cases of C++ but in general, unle…

Although some people, like Bjarne Stroustrup, object to the term C/C++, it's a bit like Richard Stallman objecting to the term "Linux". The fact is it can mean "C or C++", and I wouldn't assume the author thinks they're the same, but they're talking about both of them together in the same sentence. This seems reasonable given this is about undefined behavior, and it's trivial to accidentally write UB-inducing code in C++ even with modern style (although I'd say you should catch most trivial cases with e.g. ubsan, and a lot of bad cases would be avoided with e.g. ranges, so I think the article is exaggerating the issue).

Re: Everything in C is undefined behavior

#15
> A problem with this is that in order to confirm the findings, you’ll need an expert human. But generally expert humans are busy doing other things.

The article suggests using LLMs to identify and fix UB. However as per the above, I think the issue is that we need more expert humans.

LLM generated code will eventually contain UB.

EDIT: added "eventually"

Re: Everything in C is undefined behavior

#19

Anyone who uses the construction "C/C++" doesn't write modern C++, and probably isn't very familiar with the recent revisions despite TFA's claims of writing it every day for decades. Far from being just "C with classes", modern C++ is very different than C. The language is huge and complex, for sure, but nobody is forced to use all of it. No HN comment can possibly cover all the use cases of C++ but in general, unle…

"C/C++" is still a useful term for the common C/C++ subset :)

As far as stdlib usage is concerned: that's just your opinion. The stdlib has a lot of footguns and terrible design decisions too, e.g. std::vector pulling in 20k lines of code into each compilation unit is simply bizarre.

Also:

- eschewing boomer loops in favor of ranges

Those "boomer loops" compile infinitely faster than the new ranges stuff (and they are arguably more readable too): https://aras-p.info/blog/2018/12/28/Modern-C-Lamentations/

- borrowing using spans and string views

Those are just as unsafe as raw pointers. It's not really "borrowing" when the referenced data can disappear while the "borrow" is active.

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