3 ms·

> Even if you do, you now have an effective comment that tells you where to look if you ever get suspicious behavior. By the time suspicious behavior happens,

> Even if you do, you now have an effective comment that tells you where to look if you ever get suspicious behavior. By the time suspicious behavior happens, isn’t it kind of a critical inflection point? For example, the news about react and next that came out. Once the code is deployed, re-deploying (especially with a systems language that quite possibly lives on an air-gapped system with a lot of rigor about updates) means you might as well have used C, the dollar cost is the same.

stouset 11mo ago
Are you with a straight face saying that occasionally having a safety bug in limited unsafe areas of Rust is functionally the same as having written the entire program in an unsafe language like C? One, the dollar cost is not the same. The baseline floor of quality will be higher for a Rust program vs. a C program given equal development effort. Second, the total possible footprint of entire classes of bugs is zero thanks to design features of Rust (the borrowck, sum types, data race prevention), except in a specifically delineated areas which often total zero in the vast majority of Rust programs.
- irishcoffee 11mo ago
  > The baseline floor of quality will be higher for a Rust program vs. a C program given equal development effort. Hmm, according to whom, exactly? > Second, the total possible footprint of entire classes of bugs is zero thanks to design features of Rust (the borrowck, sum types, data race prevention), except in a specifically delineated areas which often total zero in the vast majority of Rust programs. And yet somehow the internet went down because of a program written in rust that didn’t validate input.
  - kibwen 11mo ago
    > And yet somehow the internet went down because of a program written in rust that didn’t validate input. What? The Cloudflare bug was from a broken system configuration that eventually cascaded into (among other things) a Rust program with hardcoded limits that crashed loudly. In no way did that Rust program bring down the internet; it was the canary, not the gas leak. Anybody trying to blame Rust for that event has no idea what they're talking about.
  - nu11ptr 11mo ago
    > And yet somehow the internet went down because of a program written in rust that didn’t validate input. Tell me which magic language creates programs free of errors? It would have been better had it crashed and compromised memory integrity instead of an orderly panic due to an invariant the coder didn't anticipate? Type systems and memory safety are nice and highly valuable, but we all know as computer scientists we have yet to solve for logic errors.
  - bigstrat2003 11mo ago
    > Hmm, according to whom, exactly? Well, Google for one. https://security.googleblog.com/2025/11/rust-in-android-move-fast-fix-things.html https://security.googleblog.com/2025/11/rust-in-android-move... > And yet somehow the internet went down because of a program written in rust that didn’t validate input. You're ignoring other factors (it wasn't just Cloudflare's rust code that led to the issue), but even setting that aside your framing is not accurate. The rust program went down because the programmer made a choice that, given invalid input, it should crash. This could happen in every language ever made. It has nothing to do with rust.
    - disappoint 11mo ago
      > This could happen in every language ever made. It has nothing to do with rust. Except it does. This also has to do with culture. In Rust, I get the impression that one can set it up as roughly two communities. The first does not consider safety, security and correctness to be the responsibility of the language, instead they consider it their own responsibility. They merely appreciate it when the language helps with all that, and take precautions when the language hinders that. They try to be honest with themselves. The second community is careless, might make various unfounded claims and actions that sometimes border on cultish and gang mob behavior and beliefs, and can for instance spew unwrap() all over codebases even when not appropriate for that kind of project, or claim that a Rust project is memory safe even when unsafe Rust is used all over the place with lots of basic bugs and UB-inducing bugs in it. The second community is surprisingly large, and is severely detrimental to security, safety and correctness.
      - aw1621107 11mo ago
        I don't think you're actually disagreeing with the person you're responding to here. Even if you take your grouping as factual, there's nothing that limits said grouping to Rust programmers. Or in other words: > This could happen in every language ever made. It has nothing to do with rust.
        disappoint 11mo ago
  - SkiFire13 11mo ago
    > And yet somehow the internet went down because of a program written in rust that didn’t validate input. No, it _did validate_ the input, and since that was invalid it resulted in an error. People can yap about that unwrap all they want, but if the code just returned an error to the caller with `?` it would have resulted in a HTTP 500 error anyway.
    - irishcoffee 11mo ago
      So it validated in the input and failed in an unsafe way. Is that what you’re saying? Instead of rejecting the input and failing in a safe way. My only point was, the language doesn’t matter. It could have been written in brainfuck. I’m bitching about the rust evangelism, obviously. Neat language, protects against NPEs et. al. It isn’t a magic bullet and it never was.
      - SkiFire13 11mo ago
        > So it validated in the input and failed in an unsafe way. Is that what you’re saying? Instead of rejecting the input and failing in a safe way. It rejected the input and "failed" in a loud way (showing an error) for the user, as opposed to not rejecting the invalid input and continuing anyway in a degraded/invalid state, which would instead have allowed users to continue browsing but would not have worked properly for some other purposes (e.g. it probably would not have continued blocking malicious/bad scraper requests). Neither is ideal, though of course depending on your priorities one might be better than the other. > My only point was, the language doesn’t matter. It could have been written in brainfuck. Yeah I definitely agree. My point was that the error was also somewhere else, since an internally-controlled input was invalid.
mh2266 11mo ago
This just skips the: > First, if you aren't writing device drivers/kernels or something very low level there is a high probability your program will have zero unsafe usages in it. from the original comment. Meanwhile all C code is implicitly “unsafe”. Rust at least makes it explicit! But even if you ignore memory safety issues bypassed by unsafe, Rust forces you to handle errors, it doesn’t let you blow up on null pointers with no compiler protection, it allows you to represent your data exhaustively with sum types, etc etc etc
- irishcoffee 11mo ago
  Isn’t rust proffered up as a systems language? One that begged to be accepted into the Linux kernel? Don’t device drivers live in the Linux kernel tree? So, unsafe code is generally approved in device driver code? Why not just use C at that point?
  - stouset 11mo ago
    I am quite certain that someone who has been on HN as long as you have is capable of understanding the difference between 0% compiler-enforced memory safety in a language with very weak type safety guarantees and 95%+ of code regions even in the worst case of low-level driver code that performs DMA with strong type safety guarantees.
    - disappoint 11mo ago
      Please explain the differences in typical aliasing rules between C and Rust. And please explain posts like https://chadaustin.me/2024/10/intrusive-linked-list-in-rust/ https://chadaustin.me/2024/10/intrusive-linked-list-in-rust/ https://news.ycombinator.com/item?id=41947921 https://news.ycombinator.com/item?id=41947921 https://lucumr.pocoo.org/2022/1/30/unsafe-rust/ https://lucumr.pocoo.org/2022/1/30/unsafe-rust/
      - stouset 11mo ago
        Is three random people saying unsafe Rust is hard supposed to make us forget about C’s legendary problems with UB, nil pointers, memory management bugs, and staggering number of CVEs? You have zero sense of perspective. Even if we accept the premise that unsafe Rust is harder than C (which frankly is ludicrous on the face of it) we’re talking about a tiny fraction of the overall code of Rust programs in the wild. You have to pay careful attention to C’s issues virtually every single line of code. With all due respect this may be the singular dumbest argument I’ve ever had the displeasure of participating in on Hacker News.
nu11ptr 11mo ago
> might as well have used C, the dollar cost is the same. When your unsafe area is small, you put a LOT of thought/testing into those small blocks. You write SAFETY comments explaining WHY it is safe (as you start with the assumption there will be dragons there). You get lots of eyeballs on them, you use automated tools like miri to test them. So no, not even in the same stratosphere as "might as well have used C". Your probability of success vastly higher. A good Rust programmer uses unsafe judiciously, where as a C programmer barely blinks as they need ensure every single snippet of their code is safe, which in a large program, is an impossible task. As an aside, having written a lot of C, the ecosystem and modern constructs available in Rust make writing large scale programs much easier, and that isn't even considering the memory safety aspect I discuss above.
- disappoint 11mo ago
  SAFETY comments do not magically make unsafe Rust correct nor safe. And Miri cannot catch everything, and is magnitudes slower than regular program running. https://github.com/rust-lang/rust/commit/71f5cfb21f3fd2f1740bced061c66ff112fec259 https://github.com/rust-lang/rust/commit/71f5cfb21f3fd2f1740... https://materialize.com/blog/rust-concurrency-bug-unbounded-channels/ https://materialize.com/blog/rust-concurrency-bug-unbounded-...
  - aw1621107 11mo ago
    I think you might be misreading GP's comment. They are not claiming that SAFETY comments and MIRI guarantee correctness/safety; those are just being used as examples of the extra effort that can be and are expended on the relatively few unsafe blocks in your codebase, resulting in "your probability of success [being] vastly higher" compared to "might as well have used C".
    - disappoint 11mo ago
      [flagged]

stouset 11mo ago

Are you with a straight face saying that occasionally having a safety bug in limited unsafe areas of Rust is functionally the same as having written the entire program in an unsafe language like C? One, the dollar cost is not the same. The baseline floor of quality will be higher for a Rust program vs. a C program given equal development effort. Second, the total possible footprint of entire classes of bugs is zero thanks to design features of Rust (the borrowck, sum types, data race prevention), except in a specifically delineated areas which often total zero in the vast majority of Rust programs.

irishcoffee 11mo ago
> The baseline floor of quality will be higher for a Rust program vs. a C program given equal development effort. Hmm, according to whom, exactly? > Second, the total possible footprint of entire classes of bugs is zero thanks to design features of Rust (the borrowck, sum types, data race prevention), except in a specifically delineated areas which often total zero in the vast majority of Rust programs. And yet somehow the internet went down because of a program written in rust that didn’t validate input.
- kibwen 11mo ago
  > And yet somehow the internet went down because of a program written in rust that didn’t validate input. What? The Cloudflare bug was from a broken system configuration that eventually cascaded into (among other things) a Rust program with hardcoded limits that crashed loudly. In no way did that Rust program bring down the internet; it was the canary, not the gas leak. Anybody trying to blame Rust for that event has no idea what they're talking about.
- nu11ptr 11mo ago
  > And yet somehow the internet went down because of a program written in rust that didn’t validate input. Tell me which magic language creates programs free of errors? It would have been better had it crashed and compromised memory integrity instead of an orderly panic due to an invariant the coder didn't anticipate? Type systems and memory safety are nice and highly valuable, but we all know as computer scientists we have yet to solve for logic errors.
- bigstrat2003 11mo ago
  > Hmm, according to whom, exactly? Well, Google for one. https://security.googleblog.com/2025/11/rust-in-android-move-fast-fix-things.html https://security.googleblog.com/2025/11/rust-in-android-move... > And yet somehow the internet went down because of a program written in rust that didn’t validate input. You're ignoring other factors (it wasn't just Cloudflare's rust code that led to the issue), but even setting that aside your framing is not accurate. The rust program went down because the programmer made a choice that, given invalid input, it should crash. This could happen in every language ever made. It has nothing to do with rust.
  - disappoint 11mo ago
    > This could happen in every language ever made. It has nothing to do with rust. Except it does. This also has to do with culture. In Rust, I get the impression that one can set it up as roughly two communities. The first does not consider safety, security and correctness to be the responsibility of the language, instead they consider it their own responsibility. They merely appreciate it when the language helps with all that, and take precautions when the language hinders that. They try to be honest with themselves. The second community is careless, might make various unfounded claims and actions that sometimes border on cultish and gang mob behavior and beliefs, and can for instance spew unwrap() all over codebases even when not appropriate for that kind of project, or claim that a Rust project is memory safe even when unsafe Rust is used all over the place with lots of basic bugs and UB-inducing bugs in it. The second community is surprisingly large, and is severely detrimental to security, safety and correctness.
    - aw1621107 11mo ago
      I don't think you're actually disagreeing with the person you're responding to here. Even if you take your grouping as factual, there's nothing that limits said grouping to Rust programmers. Or in other words: > This could happen in every language ever made. It has nothing to do with rust.
      - disappoint 11mo ago
- SkiFire13 11mo ago
  > And yet somehow the internet went down because of a program written in rust that didn’t validate input. No, it _did validate_ the input, and since that was invalid it resulted in an error. People can yap about that unwrap all they want, but if the code just returned an error to the caller with `?` it would have resulted in a HTTP 500 error anyway.
  - irishcoffee 11mo ago
    So it validated in the input and failed in an unsafe way. Is that what you’re saying? Instead of rejecting the input and failing in a safe way. My only point was, the language doesn’t matter. It could have been written in brainfuck. I’m bitching about the rust evangelism, obviously. Neat language, protects against NPEs et. al. It isn’t a magic bullet and it never was.
    - SkiFire13 11mo ago
      > So it validated in the input and failed in an unsafe way. Is that what you’re saying? Instead of rejecting the input and failing in a safe way. It rejected the input and "failed" in a loud way (showing an error) for the user, as opposed to not rejecting the invalid input and continuing anyway in a degraded/invalid state, which would instead have allowed users to continue browsing but would not have worked properly for some other purposes (e.g. it probably would not have continued blocking malicious/bad scraper requests). Neither is ideal, though of course depending on your priorities one might be better than the other. > My only point was, the language doesn’t matter. It could have been written in brainfuck. Yeah I definitely agree. My point was that the error was also somewhere else, since an internally-controlled input was invalid.

mh2266 11mo ago

This just skips the: > First, if you aren't writing device drivers/kernels or something very low level there is a high probability your program will have zero unsafe usages in it. from the original comment. Meanwhile all C code is implicitly “unsafe”. Rust at least makes it explicit! But even if you ignore memory safety issues bypassed by unsafe, Rust forces you to handle errors, it doesn’t let you blow up on null pointers with no compiler protection, it allows you to represent your data exhaustively with sum types, etc etc etc

irishcoffee 11mo ago
Isn’t rust proffered up as a systems language? One that begged to be accepted into the Linux kernel? Don’t device drivers live in the Linux kernel tree? So, unsafe code is generally approved in device driver code? Why not just use C at that point?
- stouset 11mo ago
  I am quite certain that someone who has been on HN as long as you have is capable of understanding the difference between 0% compiler-enforced memory safety in a language with very weak type safety guarantees and 95%+ of code regions even in the worst case of low-level driver code that performs DMA with strong type safety guarantees.
  - disappoint 11mo ago
    Please explain the differences in typical aliasing rules between C and Rust. And please explain posts like https://chadaustin.me/2024/10/intrusive-linked-list-in-rust/ https://chadaustin.me/2024/10/intrusive-linked-list-in-rust/ https://news.ycombinator.com/item?id=41947921 https://news.ycombinator.com/item?id=41947921 https://lucumr.pocoo.org/2022/1/30/unsafe-rust/ https://lucumr.pocoo.org/2022/1/30/unsafe-rust/
    - stouset 11mo ago
      Is three random people saying unsafe Rust is hard supposed to make us forget about C’s legendary problems with UB, nil pointers, memory management bugs, and staggering number of CVEs? You have zero sense of perspective. Even if we accept the premise that unsafe Rust is harder than C (which frankly is ludicrous on the face of it) we’re talking about a tiny fraction of the overall code of Rust programs in the wild. You have to pay careful attention to C’s issues virtually every single line of code. With all due respect this may be the singular dumbest argument I’ve ever had the displeasure of participating in on Hacker News.

nu11ptr 11mo ago

> might as well have used C, the dollar cost is the same. When your unsafe area is small, you put a LOT of thought/testing into those small blocks. You write SAFETY comments explaining WHY it is safe (as you start with the assumption there will be dragons there). You get lots of eyeballs on them, you use automated tools like miri to test them. So no, not even in the same stratosphere as "might as well have used C". Your probability of success vastly higher. A good Rust programmer uses unsafe judiciously, where as a C programmer barely blinks as they need ensure every single snippet of their code is safe, which in a large program, is an impossible task. As an aside, having written a lot of C, the ecosystem and modern constructs available in Rust make writing large scale programs much easier, and that isn't even considering the memory safety aspect I discuss above.

disappoint 11mo ago
SAFETY comments do not magically make unsafe Rust correct nor safe. And Miri cannot catch everything, and is magnitudes slower than regular program running. https://github.com/rust-lang/rust/commit/71f5cfb21f3fd2f1740bced061c66ff112fec259 https://github.com/rust-lang/rust/commit/71f5cfb21f3fd2f1740... https://materialize.com/blog/rust-concurrency-bug-unbounded-channels/ https://materialize.com/blog/rust-concurrency-bug-unbounded-...
- aw1621107 11mo ago
  I think you might be misreading GP's comment. They are not claiming that SAFETY comments and MIRI guarantee correctness/safety; those are just being used as examples of the extra effort that can be and are expended on the relatively few unsafe blocks in your codebase, resulting in "your probability of success [being] vastly higher" compared to "might as well have used C".
  - disappoint 11mo ago
    [flagged]