←back to thread

Why is the Rust compiler so slow?

(sharnoff.io)
302 points Bogdanp | 6 comments | 26 Jun 25 19:29 UTC | HN request time: 1.185s | source | bottom
Show context
AndyKelley ◴[26 Jun 25 20:16 UTC] No.44390865[source]▶
My homepage takes 73ms to rebuild: 17ms to recompile the static site generator, then 56ms to run it.

    andy@bark ~/d/andrewkelley.me (master)> zig build --watch -fincremental
    Build Summary: 3/3 steps succeeded
    install success
    └─ run exe compile success 57ms MaxRSS:3M
       └─ compile exe compile Debug native success 331ms
    Build Summary: 3/3 steps succeeded
    install success
    └─ run exe compile success 56ms MaxRSS:3M
       └─ compile exe compile Debug native success 17ms
    watching 75 directories, 1 processes
replies(8): >>44390894 #>>44390942 #>>44390948 #>>44391020 #>>44391060 #>>44391265 #>>44391881 #>>44393741 #
echelon ◴[26 Jun 25 20:20 UTC] No.44390894[source]▶
Zig is a small and simple language. It doesn't need a complicated compiler.

Rust is a large and robust language meant for serious systems programming. The scope of problems Rust addresses is large, and Rust seeks to be deployed to very large scale software problems.

These two are not the same and do not merit an apples to apples comparison.

edit: I made some changes to my phrasing. I described Zig as a "toy" language, which wasn't the right wording.

These languages are at different stages of maturity, have different levels of complexity, and have different customers. They shouldn't be measured against each other so superficially.

replies(2): >>44390901 #>>44391486 #
1. steveklabnik ◴[26 Jun 25 20:21 UTC] No.44390901[source]▶
Come on now. This isn't acceptable behavior.

(EDIT: The parent has since edited this comment to contain more than just "zig bad rust good", but I still think the combative-ness and insulting tone at the time I made this comment isn't cool.)

replies(1): >>44390989 #
2. echelon ◴[26 Jun 25 20:29 UTC] No.44390989[source]▶
> but I still think the combative-ness and insulting tone at the time I made this comment isn't cool

Respectfully, the parent only offers up a Zig compile time metric. That's it. That's the entire comment.

This HN post about Rust is now being dominated by a cheap shot Zig one liner humblebrag from the lead author of Zig.

I think this thread needs a little more nuance.

replies(2): >>44391139 #>>44394470 #
3. steveklabnik ◴[26 Jun 25 20:43 UTC] No.44391139[source]▶
FWIW, I think your revised comment is far better, even though I disagree with some of the framing, there's at least some substance there.

Being frustrated by perceived bad behavior doesn't mean responding with more bad behavior is a good way to improve the discourse, if that's your goal here.

replies(1): >>44391166 #
4. echelon ◴[26 Jun 25 20:45 UTC] No.44391166{3}[source]▶
You're 100% right, Steve. Thank you for your voice of moderation. You've been amazing to this community.
replies(1): >>44391261 #
5. steveklabnik ◴[26 Jun 25 20:55 UTC] No.44391261{4}[source]▶
It's all good. I'm very guilty of bad behavior myself a lot of the time. It's on all of us to give gentle nudges when we see each other getting out of line. I deserve to be told the same if you see me doing this too!
6. Mawr ◴[27 Jun 25 07:20 UTC] No.44394470[source]▶
> Respectfully, the parent only offers up a Zig compile time metric. That's it. That's the entire comment.

That's correct, but slinging cheap shots at each other is not how discussions on this site are supposed to be.

> I think this thread needs a little more nuance.

Yes, but your comment offers none.