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I stopped everything and started writing C again

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Re: I stopped everything and started writing C again

#341

Post by BlackFly »

mrheosuper wrote: post #304
jpc0 wrote: post #295

Earlier quoted context omitted.

What is your current language of choice, both C and C++ have the same problems as what you just described. Regarding ownership transfer it is even worse in C, what if you forget, after moving an object out of a variable, to set that variable to NULL, then free that variable, that's a use after free. At least in C++ you have move semantics although it is still error prone. In rust it's a compiler error. Copy and Clone…

Well, i dont use C++ much(i'm FW engineer, most of my stuff is in C). The std in C is simple and explicit. For Ex: I can make an educated guess how memcpy() work by looking at its signature. It takes pointer to src and destination, and size, so i can guess it does not allocate any new memory(or if it has, it has to be some kind of optimization reason). Another example is strstr(), it returns pointer to a piece of mem…

You can surmise the behavior from the signature of clone in the same way that you can memcpy(), it returns an owned type so it will allocate. If you want to match the signature of memcpy then you don't want the allocation and you can instead call clone_from() which takes a mutable borrow of something you had to allocate.

> piece of memory i provided to it, so i can safely do some pointer math with the return value.

Except pointer math is never going to be safe in C, a particular case might be bugfree but it is not safe. Moreover, nothing in the C language says that the provenance of the output pointer matches the provenance of the input pointer (it could take a reference to a pointer from some other thread while that other thread is freeing that memory). In rust you will pass a pointer and get a pointer back with the same lifetime, then you can safely use the pointer in that lifetime bound: the provenance is part of the signature. So in this case, you are incorrectly assuming things from the C signature while the corresponding rust signature definitively tells you.

So yeah, if you learn more about rust then you will see that in fact it tells you more than the corresponding C signatures.

Re: I stopped everything and started writing C again

#342

Post by randomNumber7 »

relistan wrote: post #317
TinkersW wrote: post #70

Earlier quoted context omitted.

Eh Segfaults are like the easiest error to debug, they almost always tell you exactly where the problem is.

Except when they don’t. I’m debugging something right now that runs fine under debugging conditions and crashes with a segfault in real life. It’s not randomized memory (messed with that), it’s likely some race where the timing is changed by the debugger.

AdressSanitizer is an absolute gamechanger and should amost always spare you the effort of the nightmare debugging of undefined behaviour.

Re: I stopped everything and started writing C again

#343

Post by cassepipe »

I did come back to C after some years. I liked it because it made me suffer but in the I prevailed so I felt good about it. Now that I am back at it I remember all the pain of trying to enforce abstractions at compile-time with the C preprocessor. I am now considering Zig or suicide.

Re: I stopped everything and started writing C again

#344

Post by pansa2 »

hgs3 wrote: post #187
lqet wrote: post #11

I fully understand that sentiment. For several years now, I have also felt the strong urge to develop something in pure C. My main language is C++, but I have noticed over and over again that I really enjoy using the old C libraries - the interfaces are just so simple and basic, there is no fluff. When I develop methods in pure C, I always enjoy that I can concentrate 100% on algorithmic aspects instead of architectu…

Agreed. C, Go, Python, and Lua are my go-to languages because of their simplicity. It's unfortunate, but in my opinion, most mainstream languages are needlessly complex. In my experience, whether it's software architecture or programming language design, it's easy to make things complicated, but it takes vision and discipline to keep them simple.

> C, Go, Python, and Lua are my go-to languages because of their simplicity

One of these things is not like the others! Python's complexity has been increasing rapidly (e.g. walrus operator, match statement, increasingly baroque type hints) - has this put you off the language at all?

Re: I stopped everything and started writing C again

#345

Post by seba_dos1 »

kstrauser wrote: post #144
kelnos wrote: post #127

I'm kinda in the opposite camp. After doing a bunch of VB in my tweens and teens, I learned Java, C, and C++ in college, settling on mostly C for personal and professional projects. I became a core developer of Xfce and worked on that for 5 years. Then I moved into backend development, where I was doing all Java, Scala, and Python. It was... dare I say... easy! Sure, these kinds of languages bring with them other pro…

I think Rust is harder to learn , but once you grok it, I don't think it's harder to use , or at least to use correctly. It's hard to write correct C because the standard tooling doesn't give you much help beyond `-Wall`. Rust's normal error messages are delightfully helpful. For example, I just wrote some bad code and got: --> src/main.rs:45:34 | 45 | actions.append(&mut func(opt.selected)); | ---- ^^^^^^^^^^^^ expe…

> It's hard to write correct C because the standard tooling doesn't give you much help beyond `-Wall`

I won't disagree that correct C is harder to write, but it's not 2005 anymore and standard tooling gives you access to things like asan, msan, ubsan, tsan, clang-tidy...

Re: I stopped everything and started writing C again

#346

Post by pansa2 »

Klonoar wrote: post #325
BigJono wrote: post #240

Earlier quoted context omitted.

You come off as incredibly arrogant too, you just don't realise it because you have the current mainstream opinion and the safety of a crowd. Do you know how fucking obnoxious it is when 200 people like you come into every thread to tell 10 C or Javascript developers that they can't be trusted with the languages and environments they've been using for decades? There are MILLIONS of successful projects across those tw…

Nobody is telling JS developers that Rust will save them, chill.

But you'll be called things like "catastrophically unprofessional" [1] if you choose JavaScript over TypeScript, or dynamically-typed Python over MyPy.

[1] https://www.reddit.com/r/Python/comments/1iqytkf/python_type...

Re: I stopped everything and started writing C again

#349

Post by surajrmal »

ChrisMarshallNY wrote: post #340
kelnos wrote: post #227

Earlier quoted context omitted.

Sure, that's a pretty common pattern in use in C to this day. It's a useful pattern, but it's still all manual. Forget to fill in a function pointer in a struct? Crash. At least with C++ it will fail to compile if you don't implement a method that you have to implement.

> still all manual That pretty much is the definition of C. It was designed to be a system language, that was "one step beyond" (my own Madness reference) the assembler. It's a dangerous tool, and should be wielded by experts. The same goes for all kinds of similar stuff. And "experts" is kind of a darwinian thing. There's not really that many folks that can successfully wield it in large quantities (a certain cranky…

I've never met an expert who writes c well all of the time, so I have been led to believe it's simply not possible. Folks with 20+ years of experience will still regularly write a use after free but which is not caught until it hits production. I'm not sure I've actually seen C code free of concurrency bugs. If it's possible it takes years of battle hardening with no feature work. Humans are prone to make mistakes and we need to use as many tools as possible to help us avoid making those mistakes. They are recently looking into introducing thread annotations for locks in the Linux kernel and I expect them to find lots of real bugs lurking in otherwise well maintained subsystems. I've rewritten swaths of code into rust and always seen it find a bug in the original code's design that we were lucky to never run into.

Re: I stopped everything and started writing C again

#350

Post by pabs3 »

swiftcoder wrote: post #314
pabs3 wrote: post #275

Earlier quoted context omitted.

You might want to reconsider use of rust-analyzer, it isn't safe to use on code you haven't written yourself. https://rust-analyzer.github.io/book/security.html

> it isn't safe to use on code you haven't written yourself Neither is cargo (nor npm, nor any other package manager, for that matter). I'm not sure what value being that paranoid is buying you in the long run.

Package managers are for running other people's code, I would not expect the same of static analysis tools, especially since they are of use while auditing other people's code before building/running it.
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