> I don't think that that's true. I find the explanation given by "Some Were Meant for C" [1] far more plausible.

Kell's argument rests on the idea that C is doing something you can't do in safe languages. Mostly it says the safe languages are managed, and so they simply can't match C for what Kell describes as "communicativity" which we will see shortly isn't meaningfully true.

Now, one of the first examples Kell gives (from Duff's device) is something Dennis Ritchie thought was a huge mistake, the volatile qualifier. In C we can do MMIO the same way as in machine code, we refer to a volatile "object" that's actually not really in memory, the CPU fetches and stores will be issued and the MMIO happens. In a language like Rust this doesn't work, they have intrinsics which actually emit the same machine code, but there is no pretend object.

Kell, like many C programmers, thinks C is revealing an important truth here, but it's actually keeping up a damaging masquerade. That object is a lie, to the extent we write code which pretends it's real that code is misleading and sooner or later a maintenance programmer will believe the lie and cause problems. MMIO is similar to memory access not because of some "truth" but just because it was technically convenient.

[[ The other notable thing the volatile qualifier is (ab)used for is once again in MSVC. Microsoft semantics for volatile are atomic Acquire-release so you can use it for IPC and even within a concurrent program. That's not what it was for on Unix, it's not what the standard says it does, but it's how it happened to work on a single x86 CPU so that's what MSVC provides even today, and even on ARM if you accept the resulting performance penalty. ]]

But even outside of volatile, which again is definitely a bad idea, Kell says C is better than the safe languages because of communicativity, his next examples are just data in memory, but they are "foreign" to the software. C will be able to access this data as raw bytes.

If your experience of managed languages is, as Kells' seems to have been, a Lisp, then maybe the ability to access bytes of memory is remarkable. But you don't need Rust to do this from a safe language. C# isn't just safe it's a managed garbage collected language, yet it can do access to a byte slice just as well as C. Given a slice of bytes, step through it, one instruction at a time (with the size of an instruction to be established by a separate function) and ask a callback to look at those instructions. No problem in C#.

The false belief that everything is just C anyway causes significant grief. C programmers tend to see text and think this means C's weird NUL-termination rule applies. So given the string "microsoft.com\0bo-chicken.example.com" and asked whether it's exactly "microsoft.com" the C code says yes, opening a security vulnerability. This really happened, and yet of course C programmers insisted it's somebody else's fault. And that's key here, Kell's examples are "foreign" in the sense that they aren't from this C program. But these examples aren't structures from Java, or Scheme, or even Rust, they're just from a different C program. This "communicativity" is unimaginitive.

It reminds me of colonial Europeans passing judgement on the "savage" inhabitants of a place they've now decided belongs to them. Why don't these useless Indians have properly 0-byte terminated strings? And why are their symbol names so complicated? No no, this is all wrong, the correct way is the way I grew up with, and any alternative is not better, nor even just different, but necessarily wrong.

The "safety" Kell envisions for a hypothetical safer C implementation relies on saying that behaviours which have been passionately defended here by C programmers including yourself as needing to be defined are Undefined and so can safely be outlawed. Aliasing between types? Kell says you shouldn't expect that to work and so it shan't in his safe C.

Finally Kell comes back to is an assumption which is small in C but grew enormous in C++ about what we should do if the programs might be nonsense. Rice's Theorem says we can't necessarily decide if semantic properties hold for arbitrary programs. To defuse this problem we sometimes give up instead. Thus, a program to decide if another program is correct (such as a compiler) will have three possible results, Correct, Wrong and Not Sure. It's obvious what to do with the first two categories but that leaves us with Not Sure. In both C and C++ the answer is those programs go in the Correct bucket anyway and we cross our fingers.

Rust says no, all the "Not sure" programs go in the "Wrong" bucket and the programmer can just modify the program until it's Correct so we're fine. This is a pragmatic engineering response. Our dynamic analysis says this new bridge might literally explode, I think the analysis method may be wrong about that, but I can't prove it. Should we build the bridge anyway and see if it explodes? No! Design a bridge that passes analysis!

The Rust and C++ approaches have very different incentives for language designers. In Rust the incentive is to shrink that "No sure" pile, because it annoys programmers. Non-lexical lifetimes are an example of that shrinking process. A Rust program with NLL was always actually fine, but before the NLL change landed in the compiler it would be rejected because it was in the "Not sure" category. In C++ the incentive is to grow the "Not sure" category because every program we can convince ourselves might be correct is another C++ program in the Correct bucket. Some, perhaps many, perhaps even most are nonsense, but at least some of them are correct and we don't care to distinguish. The same tendency exits, to a lesser extent, in C itself.