Thread by @ekuber

#RustConf 2022 is kicking off!

Thank you @nellshamrell for kicking off RustConf!

The Opening Keynote with @josh_triplett:
"Everything you want to know about the current and future state of the Rust project, team and community."

Josh went from presenting his first time about introducing `union`, to giving the "state of the union".

Damn, yes. I quite forget that `?` hasn't been there from the beginning 😅

Aside: shout out to @yaahc_ for her work on Error handling

@yaahc_ "Rust and The Community evolve *together*" — @josh_triplett

You can't goo too quickly or too slowly when stabilizing. You need to find a balance to avoid breakage or stifling progress.

blog.rust-lang.org/inside-rust/20…

Upcoming changes to make it clearer (and easier as possible) to figure out how contribute

Update on Rust governance: "We found some UB in our governance. We're working on new structures, and we want to enable smooth evolution over time."

RustConf PostConf UnConf happening tomorrow

@tmandry kicking his talk now
"Where did you goooo🎵"

Guest @RustConf appearance: @jckarter

@rustconf @jckarter "Stay curious. Openness is not about winning, it's about changing minds and allowing others to change yours. When you have a shared inspiration and move in sync, building something together becomes much easier." — @tmandry

@rustconf @jckarter @tmandry Inclusion is hard, but it is Rust's strength.

@rustconf @jckarter @tmandry It's ability to bring together seasoned and novice system programmers, both imperative and hardcore functional programmers, and enabling them to build things with a level of safety that wasn't possible before. Inclusion lies at the heart of that.

@rustconf @jckarter @tmandry *Editor's note: @tmandry dropping *the* quote of the conference one after another

@rustconf @jckarter @tmandry @tmandry slipping into our DMs: "Hey Rust? How are you doing?"

@rustconf @jckarter @tmandry "30% of people who tried to contribute, didn't succeed"

@rustconf

@rustconf "I want to make sure I'm engaging the more appropriate members of the audience"

@rustconf

@rustconf Now @mycoliza showing off github.com/tokio-rs/conso…, courtesy of Penumbra

@rustconf @mycoliza Julia Wang in the break out chat talking about trains is fascinating. Letting us know that trains are mandated to have three lights, and not two so they can be distinguished from cars from afar. So all trains have their two eyes and their third eye wide open.

@rustconf @sgrif showing off in the break out chat, letting us know that they've seen all the talks already (because that's how RustConf operates), and that Julia's closing talk is amazing. So make sure you don't miss it!

@rustconf Seriously, there are Software Engineers and Software *Engineers* 🚂

@rustconf @nick_r_cameron talking about async/await past present and future, who apparently doesn't have a single fun fact about himself, which I guess is a fun fact

@rustconf What makes Rust, Rust?

@rustconf "zero-cost abstractions"
take a shot 🥂

@rustconf > Wait, is this a fun fact or `fn` fact?

@rustconf > Nick really should present about past, present and future at the same time 🙂

@rustconf *Editor's note: @nick_r_cameron's next talk needs to be called "Everything everywhere all at once: async/await in Rust" 👀

@rustconf Chat side-channel: impl Future<Output = !>, and other types dreamed up by the utterly unhinged

@rustconf > I feel a GATs mention coming in hot
5 seconds later:

@rustconf (^ take another shot 🥂)

@rustconf Nick, paraphrased: "to make async/await from scratch, you first must invent IntoIterator"

@rustconf "The problem with poll", and other daytime comedies, coming soon 😅

@rustconf async/await's nemesis: borrowck and lifetimes.
Dropping a Future (or worse! mem::forget) gets us in trouble.
Cancellation has to be async too. async Drop is... tricky. But even if we had it, drop isn't guaranteed to run. We can't rely on destructor for soundness.

@rustconf Now, talking about rustc bootstrapping @joshuayn514, showing how every rustc version uses nightly features from the previous rustc version, which means that to build any given version you need to build version - 1 first. Carl Sagan apple pie, yet again.

@rustconf @joshuayn514 > will panic!("{:?}", return 42); panic or return?
If a tree falls in the woods, but there's no one to hear it, does it make a noise?

@rustconf (It returns)

@rustconf Why do we allow rustc to use nightly features? Well, we have full control of the codebase (which means we can be careful about reliance on nightly features) *and* we can dogfood them, to make them better before stabilization.

@rustconf "Compilers can be buggy"
No! That's not true! That's impossible!

@rustconf "The code compiles, but the binary does the wrong thing. That's called a miscompilation."

NOOOOOOOooooo000OOOO!!1

@rustconf Shout out to @pietroalbini's "Shipping a compiler every 6 weeks" talk
pietroalbini.org/blog/shipping-…

@rustconf "Reflection on trusting trust"
cs.cmu.edu/~rdriley/487/p…

Take a shot 🥂

@rustconf I forgot to mention earlier, but `#[yeet]`
areweyeetyet.rs

@rustconf "Our trust chain is... a bit... long"

@rustconf >> What's see plus plus?
> bifocals

@rustconf @joshuayn514 wrapping up talking about his *huge* effort to excise the need for python (x[dot]py is the entry point) for building rustc

@rustconf Honestly, it's amazing how consistently *good* RustConf is. And the discord channel is always so much fun.

@rustconf @Gankra_ is directly responsible for one of std's CVE
"What if we pretended unsafe code was nice, and then it was?"

@rustconf Of course, Aria's best known of the Rustonomicon and Learning Rust with Too Many Lists, but hasn't worked on Rust for a while. But *then* got annoyed with strict provenance.

doc.rust-lang.org/nomicon/
rust-unofficial.github.io/too-many-lists/

@rustconf So now we're stuck with no escape, the doors are locked: @Gankra_'s gonna explain memory models to us.

*Editor's note: May God have mercy on all of us.

@rustconf

@rustconf This tree house is memory. It is (Hellraiser's) Pinhead's. This tree house is bad, but it could be worse. Oh, it is worse, it's taller so we take longer to climb it. Well, it could be worse. Oh, it's worse, it's on terrible clip art fire.

@rustconf

@rustconf I have *no* idea what this part of the thread looks like without context. This is wild, y'all! Analogies on analogies on analogies! Super technical concepts! Advanced knowledge on memory models! Cache locality! (Take a drink 🥂)

@rustconf > `Pin<Head>`

@rustconf > Pinhead working on a new Configuration Management solution called Lament — @theomn

@rustconf (provenance!!) take a shot 🥂

@rustconf >> Wait, so who is Pinhead? I've never heard of Pinhead before. Is this some media I'm not familiar with?
> hellraiser / the hellbound heart
> its an old horror movie character
> The *one true* original pointer

*me, turns to dust at hellraiser being old*

@rustconf There's Miri, which runs your program in a fully sandboxed environment and keeps track of everything, which catches incorrect memory accesses. And we have CHERI which takes this concept to the hardware.

@rustconf But we gotta go fast!

@rustconf The full RustConf Discord experience

@rustconf > We sell UB at cost and make our money off pointer alignment sales — @mgattozzi

@rustconf "CHERI has perfect provenance tracking. Except for time travelers." — @Gankra_

@rustconf The temporal component rears its ugly head.

*Editor's note: this feels to me as an ad for generational arenas

@rustconf We're gonna talk about transcending reality. — @Gankra_

@rustconf @Gankra_ > 🏳️‍⚧️ clones

@rustconf Philosophical issues:
- use-after-free-via-trascendence
- CHERI really cares about all the bits in the pointer, so ptr -> int -> ptr can't work

@rustconf CHERI has a solution: use an existing ptr to use its provenance for an int that you're turning into a new ptr. Pretend that we have to do this. Because it cleans up the ptr -> int -> ptr hole when tracking pointers. Everything stays the same, but now we're being clear.

@rustconf So the final result is the same, but now Miri and CHERI can make sense of things, and help you check your code.

@rustconf

@rustconf I'd put the whole talk here, but seriously, go watch it when available.
All these APIs are unstable in std, but they are also available from crates.io/crates/sptr which polyfills all of them (the code is a few lines, nothing more), so you can use them today.

@rustconf > are we seriously sponsored by a company named "hrt"?
> this fits our community so well

@sgrif: "when is postfix unsafe coming, haha"
@josh_triplett: "We've talked a lot about postfix operators. We're seriously considering it for a lot of existing keywords, but likely not for unsafe."

@sgrif @josh_triplett @josh_triplett: "@Gankra_ has proposed postfix dereference operator, which would help a lot with pointers."
@sgrif: "that was a very detailed and thoughtful answer to my joke question"

@sgrif @josh_triplett @Gankra_ @sgrif: "here are some giveaways, react to this comment with any emoji for a chance to win"

* emoji counter starts moving like a plane on freefall *

Now, after a cute dog, @mgattozzi talking about github.com/rust-lang/rust…

The word `u8` has lost all meaning

Now, @AliceICecile to convince you that your open source project needs a project manager

Get other people to do your job for you. Make yourself not the single point of failure.

I'm gonna have to stop the live tweeting sadly, due to timezones. I can't wait to see the rest.
The slides for @Gankra_'s talk are available at gankra.github.io/talks/strict-p…

I hope this was useful/enjoyable to you all!

🚍

BTW, shout out to goose.rs for knowing it's audience

So after I went to bed, I got pinged on discord because I got quoted by @_lrlna 😅

https://twitter.com/ekuber/status/1493985407670837256

I have to say, I love the aesthetic of the slides. If the stream still exists tomorrow I'll watch it delayed, otherwise I'll be eagerly waiting to the uploads.