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Comment by deafpolygon | Hacker News Reader

Five years later...

"Welp, back to C because AMD's performance is overtaking ours."

Ada/SPARK is a strong typed C with visibility done correctly. (you know the "private" notion in C++ ... and sane scoping using semantic grade packages) All checks in Ada/SPARK can be removed so essentially you end up, in production, with code as performant as C.

This is only true if your C code is as correct as your Ada/SPARK code. Incorrect software can run faster than correct software...

So true! A loop that crash at the first iteration of a zillion is quick as electricity in a NOR gate.

I'm following the work of the rust compiler team these days, they're trying to leverage all rust frontend guarantees to perform better optimisations.

AMD drivers are crap though, it's not an old joke it's current, for the last 6months AMD drivers are riddle with driver timeout ( Timeout Detection and Recovery ), chrome hw acceleration not working, bsod, black screen etc ... really that bad.

https://www.reddit.com/r/Amd/comments/xvtn2u/amd_your_driver...

Truth is to have good drivers you need a lot of people and $$$, Nvidia has the upper hand on that.

AMD drivers on Linux have been getting better. Though don’t I run a bleeding edge card …

YMMV! As an non-power, graphics-wise, Linux user (that is, no 3d), my experience has been better with AMD than Nvidia (owned multiple Nvidia cards and a modern AMD one).

In daily usage, I think I've found one issue with the AMD card, and a couple with the Nvidia card. What's worrying is that when filing bugs while using an Nvidia card, devs both times gave the pseudo-automated answer "we can't solve that, Nvidia drivers are closed source", which was wrong in one case.

In Windows, I've used all the cards for gaming only, and never had any issues.

Agreed that YMMV, I have heard about these issues in that reddit thread about NVIDIA cards as well and have experienced the hardware acceleration bug for example.

This is about firmware, nothing to do with the performance of GPUs...

Firmware and drivers have a massive impact on the performance of GPUs. It's not just hardware.

The article states they had no performance hit from switching to SPARK.

It’s rare to see a thread where everyone is simultaneously correct but talking past each other.

None of you are mistaken.

I noticed this happening and just stopped replying :p

This is for _security_.

https://www.slideshare.net/AdaCore/securing-the-future-of-sa...

Yes, and security has a large performance impact.

Just look at the performance costs of bounds-checking array access in C++ code.

Or more macro, the performance impacs of AV tools or Windows Defender on your system

Wouldn’t the performance costs of bounds checking on arrays be the same if the computer was doing it or if your code was doing it?

By that logic C/C++ doing no bounds checking speeds your code up?

Well, yes, it does. Whether or not that’s a good tradeoff is a different question.

Yes, which is why compiling on different optimization settings will have bounds checking on or off in C++

> Wouldn’t the performance costs of bounds checking on arrays be the same if the computer was doing it or if your code was doing it?

It depends. The C programmer can choose to do the bounds checking in a for loop by just checking once before the loop begins, or once per iteration even if an array is accessed multiple times in the loop, or the safe language might have more overhead than a simple if statement in the C code. This can, of course, go the opposite direction (the safe language has verified the loop bounds, but the C programmer is checking before every array access). It's a battle between the C programmer and the designer and/or implementer of the safe language.

One of the reasons I like C is it gives you more control. This can be a good or a bad thing. This can lead to some really performant code you couldn't do in most languages or it can lead to some gnarly security problems. Maybe both in the same spot of code.

I use C to write mostly pet projects at home. I use it at work without having a choice in the matter.

>Just look at the performance costs of bounds-checking array access in C++ code.

If your compiler can prove you dont need bounds-checking it will remove the check and the performance would be the same. Hence, if your program has been proven to have no runtime errors you dont need them.

> If your compiler can prove you dont need bounds-checking it will remove the check and the performance would be the same

and in practice that is a very big "if"

> Yes, and security has a large performance impact.

Not necessarily. The linked blog talks about SPARK which is about running your code through theorem provers to mathematically formally verify that your code does the correct thing _in all instances_.

Once you have passed this level of verification - you can disable assertions and checks in the release version of the application (whilst of course - having the option of keeping them enabled in development releases).

Did you read the article? They said there was no performance hit.

"Did you read the article?" is a particularly unhelpful comment when the linked article has been hugged to death, and the real article is behind a sign in wall.

Well sometimes people don't. I know I've done this on occasion. Just read the title and dive in with my own opinion.

Yup. I don't think HN can avoid this at scale, though. It's been a problem on sites like this since early in the days of Slashdot.

The fundamental problem is that the voting and karma system actively incentivizes this kind of behavior. No amount of "did you read the article?" comments can counteract that force. All they do is increase the noise level even further.

I read it using the archive.org link. Should people comment without having read the article and knowing what it claims?

> "Did you read the article?" is a particularly unhelpful comment when the linked article has been hugged to death, and the real article is behind a sign in wall.

As is making assumptious comment without reading the article, especially when the comment may be wrong. I think it's not only unhelpful, but actually harmful, because other people, who also jump straight to comment section, may form an opinion based on misinformation. Also, timbit42 did provide us with what they read in the linked content; unless they added it with an edit.

Are you kidding? Asking if people read the article is more helpful when there's an unusually large number of people that haven't.

And if they need help accessing it, help can be arranged.

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