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Uninitialized memory: Unsafe Rust is too hard

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Re: Uninitialized memory: Unsafe Rust is too hard

#11

Post by ccleve »

sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

Why was this downvoted? Rust may be the "most loved" language, but after a few weeks with it, I don't love it. We've got to face the reality that it makes simple things way too complicated.

In fairness, I have found the compiler errors to be extremely helpful. They often tell me exactly what to fix. But honestly, they shouldn't have to do that. The syntax should have been obvious from the beginning, as it is in most programming languages.

Re: Uninitialized memory: Unsafe Rust is too hard

#12

Post by TheCycoONE »

sharikous wrote: post #6

What is the reason for the rule objects have to be always in a good state even inside unsafe?

Because the compiler makes assumptions on the valid layouts of a type, e.g. packing Option in a single byte. Prior to 2018 it was assumed the UB was only on read like C but that turned out not to be the case. To avoid this the type has to reflect that it might be uninitialized - hence the transparent MaybeUnit wrapper.

Re: Uninitialized memory: Unsafe Rust is too hard

#13

Post by notpopcorn »

> So we use a &'static str here instead of a C string so there are some changes to the C code.

> [..]

> So why does this type not support zero initialization? What do we have to change? Can zeroed not be used at all? Some of you might think that the answer is #[repr(C)] on the struct to force a C layout but that won't solve the problem.

The type of the first field was switched to a type (&str) that specifically promises it is never null. If the original type (a pointer) was kept, or a Option was used, mem::zero would've worked fine.

Re: Uninitialized memory: Unsafe Rust is too hard

#14

Post by eminence32 »

sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

I suspect you might start to receive a bunch of replies from people with the opposite experience (replies from people who find the syntax easy to read, and the compiler errors clear and understandable). I would like to attempt to preempt that by noting that it's totally reasonable for two people to feel drastically different things about a programming language. Neither view is more correct than the other.

That said, I am curious why different people have these different feelings. One aspect is likely rooted in the fact all of our brains are different. But I also wonder if first impressions play a big role here. A good example of a cryptic rust error is the `expected type Foo, but found type Foo` error message which is very inscrutable, especially to a new users. There are also some lifetime errors that can be hard to understand.

I wonder if someone encounters these type of messages very early on in their learning experiences, the unpleasantness of having to decipher them colors the rest of their learning experiences.

Re: Uninitialized memory: Unsafe Rust is too hard

#15

Post by creata »

ccleve wrote: post #11
sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

Why was this downvoted? Rust may be the "most loved" language, but after a few weeks with it, I don't love it. We've got to face the reality that it makes simple things way too complicated. In fairness, I have found the compiler errors to be extremely helpful. They often tell me exactly what to fix. But honestly, they shouldn't have to do that. The syntax should have been obvious from the beginning, as it is in most…

What syntax "should have been obvious from the beginning"? I always felt like most things in Rust are around as simple as they could be, for the things the language is trying to do.

Re: Uninitialized memory: Unsafe Rust is too hard

#16

Post by Tozen »

sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

I believe that different programming languages resonate better with some more than others. Often it's a matter of preferences, comfort, perceived usability, and previous experiences.

So, it's quite possible for various people to feel more comfortable using Golang than Rust, and the opposite can be true as well, where using Rust is preferred over Golang. At the end of the day, it will usually come down to individual or corporate priorities.

Another of the newer languages that fall into a similar usage space would be Vlang (https://github.com/vlang/v). It being debatably easier to learn and use, in the context of languages that more easily interact with C.

Re: Uninitialized memory: Unsafe Rust is too hard

#17

Post by howinteresting »

ccleve wrote: post #11
sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

Why was this downvoted? Rust may be the "most loved" language, but after a few weeks with it, I don't love it. We've got to face the reality that it makes simple things way too complicated. In fairness, I have found the compiler errors to be extremely helpful. They often tell me exactly what to fix. But honestly, they shouldn't have to do that. The syntax should have been obvious from the beginning, as it is in most…

Rust also makes complicated things really simple, which is why it's been the most loved for many years in a row.

Re: Uninitialized memory: Unsafe Rust is too hard

#18

Post by wyldfire »

jcranmer wrote: post #5

In C, when you declare 'struct role r' (not as a static variable), it is not zeroed. The immediate Rust equivalent would be to use std::mem::uninitialized(), not std::mem::zeroed.

But an idiom from C which might inspire some unsafe rust is to memset a struct to zero after declaration in order to guarantee that all fields are initialized before anything would access them.

Re: Uninitialized memory: Unsafe Rust is too hard

#19

Post by scrubs »

sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

Agree. I don't need to get 10 Phds figuring out Rust. At this point in my career distributed algos/systems are much more interesting to understand and implement. And writing those in a way that are bindable to multiple clients means staying close to C/Zig/C++.

Over the years the following C++ aspects have and continue to drive me nuts. On a scale of (Sarcasm coming next) 10:

* (7/10) build time, and dependency management with the 81 million tools, formats, approaches to deal with this.

* (1/10) 21 page error sets resulting from single word typos in templated code: even Egyptologists ask how do we put up with that? At least we have nice rocks to look at. Yah, they have rocks. How come we don't have rocks?

* (1/10) Code decl duplication between .h/.cpp

* (1/10) Long, pointless C++ errors. if you have an orthodox background the guilt trip C++ lays on for mismatched function calls is legion; you really feel it. It tells you such-n-such function could not be matched ... but look at the 42 million function calls you could have made ... should have made ... and it's killing me you didn't make; you seeing the effort I'm putting into this? It's killing me ... I just need the cop to say it straight: you screwed up. Ticket. See in court. Have a nice day. I prefer one liners.

I'm in no rush to waste time on Rust. I'd rather stick to GO where I can, Zig when I can. At the office we're 65% C++, 25% C. Stack overflows, memory corruptions do occur periodically; I've sorted several of those out. But the new code is C++ which makes heavy use of STL. Much better. There is growing adoption in GO and Rust, but the vast amount of C/C++ code means the apple will not fall too far from the tree.

Re: Uninitialized memory: Unsafe Rust is too hard

#20

Post by Arch-TK »

sidkshatriya wrote: post #10
sAbakumoff wrote: post #7

I am under the impression that even _safe_ Rust is really hard to learn. Several years ago I started with GoLang and it was so easy to start programming even advanced things almost instantly..Rust drives me crazy. The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful.

> I am under the impression that even _safe_ Rust is really hard to learn. [...] > The syntax seems overcomplicated, the compiler errors are cryptic, the IDE is not helpful. Yes, Rust is hard to learn. Rust does _seem_ over-complicated. However I like to compare Rust to exercise. You need to do a bit of it before you start reaping the benefits of it. If you suspend your judgement for a bit and try to write some Rust,…

>It would have been able to very difficult for me to understand the codebase if it were written in C/C++!

I find rust and modern C++ codebases equally hard to understand. How can you be so sure that the reason you find it easier to understand is not simply because you know rust better than C or C++?

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