rust-lang/rust on Hacker News

…like a segfault out of nowhere in safe Rust? The issue is still open after two years by the way: https://github.com/rust-lang/rust/issues/107975

comment by tw061023 · 2025-07-25 · in New Aarch64 Back End

…its various soundness holes as bugs that need to be fixed. It's just that some of them, like https://github.com/rust-lang/rust/issues/25860 (which I assume you're referring to), need major refactors of certain parts of the compiler in…

comment by ameliaquining · 2025-07-24 · in There is no memory safety without thread safety

…but that is opt-in, while it is always on for Rust. And there is newer UB as well in Rust stdlib https://github.com/rust-lang/rust/pull/139553

comment by hamcocar · 2025-07-10 · in Tree Borrows

…the libraries you use do not have UB. If you have no unsafe, but your library does, you can get UB. https://github.com/rust-lang/rust/pull/139553 This is why it may be a good idea to run MIRI on your Rust code, even when it has no unsafe,…

comment by gronpi · 2025-07-10 · in Tree Borrows

One example of MIRI not being guaranteed to handle all cases. https://github.com/rust-lang/rust/pull/139553#issuecomment-2... The above issue was part of diagnosing UB in Rust stdlib.

comment by gronpi · 2025-07-10 · in Tree Borrows

…in Rust for mutable references. And the rules of Rust have tripped up even senior Rust developers. https://github.com/rust-lang/rust/commit/71f5cfb21f3fd2f1740... Without MIRI, a lot of Rust developers would be lost, as they do not even…

comment by gronpi · 2025-07-10 · in Tree Borrows

https://github.com/rust-lang/rust/issues/143714

comment by josephg · 2025-07-10 · in # [derive(Clone)] Is Broken

…about 5% performance improvement in terms of runtimes[0], though the data is obviously very old. https://github.com/rust-lang/rust/issues/54878#issuecomment-...

comment by ivanbakel · 2025-07-09 · in Tree Borrows

…Borrows. [1] https://github.com/Voultapher/sort-research-rs/blob/main/wri... Miri column [2] https://github.com/rust-lang/rust/blob/6b3ae3f6e45a33c2d95fa...

comment by Voultapher · 2025-07-09 · in Tree Borrows

Would you mind filing a ticket on GitHub.com/rust-lang/rust with that exact request? (I'm on the go and am not logged on GitHub on this device and wouldn't want this feedback to be lost). This should be relatively easy to add and I agree…

comment by estebank · 2025-07-09 · in # [derive(Clone)] Is Broken

…use `unsafe`, not only is Rust's borrow checker not formally verified, there are soundness holes ( https://github.com/rust-lang/rust/issues?q=is%3Aopen%20is%3A... ). However, in theory it's possible to formally prove that a subset of Rust…

comment by armchairhacker · 2025-07-07 · in My first verified imperative program

…indicative, the submitter posted an update about how it was fixed. This may be a better example. https://github.com/rust-lang/rust/issues/132064 >cargo check with 1.82: 6m 19s >cargo check with 1.81: 1m 22s It may be difficult to fix.…

comment by resurrectedcyb · 2025-07-07 · in Building the Rust Compiler with GCC

…compile times of some practical Rust projects after they upgraded compiler version, for instance in https://github.com/rust-lang/rust/issues/75992 . It would be good if there was a formal description of at least one borrow checking…

comment by resurrectedcyb · 2025-07-07 · in Building the Rust Compiler with GCC

…to compile, borrow checker or not. https://play.rust-lang.org/?version=stable&mode=release&edit... https://github.com/rust-lang/rust/issues/75992 Some people used async in ways that surfaced these problems. Upgraded rustc, then the project…

comment by resurrectedcyb · 2025-07-07 · in Building the Rust Compiler with GCC

…evil_lincoln is doing, you have to understand very old Rust. Here's the commit that introduced it: https://github.com/rust-lang/rust/commit/664b0ad3fcead4fe4d2... fn evil_lincoln() { let evil <- log "lincoln"; } log was a keyword to print…

comment by steveklabnik · 2025-06-27 · in Weird Expressions in Rust

…macro invocations so that they get executed only once if the item they annotate hasn't changed: https://github.com/rust-lang/rust/pull/129102 There are multiple caveats on providing this to users (we can't assume that macro invocations are…

comment by estebank · 2025-06-27 · in Why is the Rust compiler so slow?

…at https://en.wikipedia.org/wiki/Python_License . Similarly, the reference Rust implementation ( https://github.com/rust-lang/rust ) is licensed under Apache 2.0 and MIT licenses. In what sense is FOSS software a kind of non-FOSS software?

comment by zahlman · 2025-06-26 · in Memory safety is table stakes

Even 'git status' gets slow on large repositories (or slow hosts). git status takes 643ms for github.com/rust-lang/rust

comment by WhyNotHugo · 2025-06-24 · in Starship: A minimal, fast, and customizable prompt for any shell

▲ 4

Naked functions are now stable in Rust 1.88

story by jag729 · 2025-06-23 · 0 comments

…in a well-designed way, or removed -- the current status is very unsatisfying and prone to bugs." https://github.com/rust-lang/rust/issues/48055#issuecomment-...

comment by kibwen · 2025-06-13 · in Rust compiler performance

…development might have otherwise dictated. FWIW while it was a factor it was just one of a number: https://github.com/rust-lang/rust/issues/36963#issuecomment-... And jemalloc was only removed two years after that issue was opened:…

comment by masklinn · 2025-06-13 · in Jemalloc Postmortem

OK, parser then: https://github.com/rust-lang/rust/tree/1.87.0/compiler/rustc... (main logic seems to be in expr.rs) vs https://github.com/ziglang/zig/blob/0.14.1/lib/std/zig/Parse... Again, for those who wish to form their own opinions.

comment by AndyKelley · 2025-06-12 · in Rust compiler performance

…in both Go and Rust: [Go] https://github.com/golang/go/blob/f18d046568496dd331657df4ba... [Rust] https://github.com/rust-lang/rust/blob/40daf23eeb711dadf140b... While Go leans on the enum value produced by `range` to act as the language's…

comment by 9rx · 2025-06-10 · in Go is a good fit for agents

…support for infinite loops without guaranteed forward progress, allowing this to be fixed: https://github.com/rust-lang/rust/issues/28728

comment by kibwen · 2025-06-07 · in Low-Level Optimization with Zig

…v.Close()`? In almost all cases, `close(2)` errors can be safely ignored. Rust also does this: https://github.com/rust-lang/rust/blob/792fc2b033aea7ea7b766...

comment by database64128 · 2025-06-04 · in (On | No) Syntactic Support for Error Handling

…hours ago. The entire error message was literally "operation not supported on this platform". Yeay. https://github.com/rust-lang/rust/issues/141854 > I'll also note that this was quite annoying to debug since the error message in its…

comment by timhh · 2025-06-01 · in Why Use Structured Errors in Rust Applications?

It’s coming soonish! There’s an accepted RFC that’s getting close to being ready to stabilize https://github.com/rust-lang/rust/issues/132162

comment by steveklabnik · 2025-05-31 · in C++ to Rust Phrasebook

…very descriptive of what this does since the operations themselves are algebraic. Also this comment https://github.com/rust-lang/rust/issues/136469#issuecomment... > > On that note I added an unresolved question for naming since algebraic…

comment by nextaccountic · 2025-05-31 · in Beware of Fast-Math

I helped design an API for "algebraic operations" in Rust: < https://github.com/rust-lang/rust/issues/136469 >, which are coming along nicely. These operations are 1. Localized, not a function-wide or program-wide flag. 2. Completely safe,…

comment by orlp · 2025-05-31 · in Beware of Fast-Math

…use unsafe Yes it does, it uses 'stdout.write_all', which ultimately uses unsafe to call libc.write https://github.com/rust-lang/rust/blob/d76fe154029e03aeb64af... The "unsafe" in uutils is just better hidden. I personally like my…

comment by TheDong · 2025-05-27 · in Yes-rs: A fast, memory-safe rewrite of the classic Unix yes command

…trick ? Edit: If I had read the next paragraph, I'd have learn about [1] before commenting [1] https://github.com/rust-lang/rust/issues/140167

comment by smallpipe · 2025-05-22 · in Improving performance of rav1d video decoder

The associated issue for comparing two u16s is interesting. https://github.com/rust-lang/rust/issues/140167

comment by mmastrac · 2025-05-22 · in Improving performance of rav1d video decoder

…loop, can quickly balloon from O(N) to O(scary). https://github.com/PSeitz/lz4_flex/issues/147 https://github.com/rust-lang/rust/issues/117545 If I'm reading that log-log plot right, that looks like a significantly worse than 100x slowdown…

comment by MaulingMonkey · 2025-05-21 · in Writing into Uninitialized Buffers in Rust

…the bug in question, it has been quite "popular" for about 5 years now, and is actively tracked : https://github.com/rust-lang/rust/issues/110338 . Nothing really weird. Just async hitting the limits of the current rust design.

comment by bsaul · 2025-05-16 · in Java at 30: Interview with James Gosling

i didn't "find" it. As i said, it's a well known one : https://github.com/rust-lang/rust/issues/110338 Simply using axum with code using multiple layers of async was enough. But then again, it looked like this bug (the error message is the…

comment by bsaul · 2025-05-16 · in Java at 30: Interview with James Gosling

…how useful those were. EDIT: okay, so I'm doing some digging: error codes were added before 1.0... https://github.com/rust-lang/rust/commit/0e80dbe59ea986ea53c... > This implements the minimal scaffolding that allows mapping diagnostic…

comment by steveklabnik · 2025-05-16 · in Evolution of Rust Compiler Errors

…under -used in Rust, not overused. If that does become a problem, there are also techniques like https://github.com/rust-lang/rust/issues/68262 too.

comment by steveklabnik · 2025-05-10 · in Rust’s dependencies are starting to worry me

…https://github.com/geiger-rs/cargo-geiger . The Rust compiler has some unsoundness issues such as https://github.com/rust-lang/rust/issues/84366 . Those would need fixing or linter coverage.

comment by mleonhard · 2025-05-10 · in Rust’s dependencies are starting to worry me

Rust had something similar: https://github.com/rust-lang/rust/issues/13871

comment by kevinmgranger · 2025-05-02 · in Don't watermark your legal PDFs with purple dragons in suits

▲ 2

Tracking Issue for experimental yeet expressions (feature(yeet_expr))

story by _alternator_ · 2025-04-30 · 0 comments

…s.rust-lang.org/t/expose-llvms-or-disjoint-i... - https://github.com/rust-lang/libs-team/issues/373 - https://github.com/rust-lang/rust/pull/124601 Which ultimately culminated in an opinion that should sound familiar -…

comment by alion02 · 2025-04-30 · in Performance optimization is hard because it's fundamentally a brute-force task

https://github.com/rust-lang/rust/issues/28728

comment by gavinhoward · 2025-04-26 · in Exploiting Undefined Behavior in C/C++ Programs: The Performance Impact [pdf]

▲ 1

Rust Let-Chains Stabilized

story by dabinat · 2025-04-23 · 0 comments

…and needs to be qualified. You probably noticed, but it should become a thing in RFC 3591: https://github.com/rust-lang/rust/issues/134691 So it does kind of work on current nightly: #![feature(import_trait_associated_functions)] use…

comment by higherhalf · 2025-04-21 · in Pipelining might be my favorite programming language feature

…in the README seems to be outdated, there's more up-to-date progress on reproducible rustc at https://github.com/rust-lang/rust/issues/129080

comment by csense · 2025-04-20 · in Bootstrapping Rustc from Source

…blog post to compare modern typestate patterns to the historical built-in typestate mechanism. https://github.com/rust-lang/rust/issues/2178

comment by zokier · 2025-04-20 · in Pretty State Machine Patterns in Rust (2016)

…append .patch or .diff to any PR or commit URL, and you'll get back a git-formatted patch or diff. https://github.com/rust-lang/rust/pull/139966 https://github.com/rust-lang/rust/pull/139966.patch https://github.com/rust-lang/rust/pull/1399…

comment by tomjakubowski · 2025-04-18 · in Shell-secrets – GPG-encrypted environment variables

…is immediate: ```rs fn main() { loop {} } ``` I think this can even cause Undefined Behavior :) https://github.com/rust-lang/rust/issues/28728

comment by LoganDark · 2025-04-16 · in How to Optimize Rust for Slowness: Inspired by New Turing Machine Results

…to the world should have been used instead. Very very old Rust had "crate files" which were this https://github.com/rust-lang/rust/blob/a8eeec1dbd7e06bc811e5... .rc standing for "rust crate" There's pros and cons here. I'm of two minds.

comment by steveklabnik · 2025-04-15 · in Two Years of Rust

…is how you signal to the compiler that “atomically writing two values at once” might happen). https://github.com/rust-lang/rust/pull/68491

comment by Georgelemental · 2025-04-10 · in A surprising enum size optimization in the Rust compiler