compile error: use of unstable library feature 'stdsimd' about ahash

[Amanieu]

This was stabilized in 1.72.

[bk2204]

I'd greatly appreciate it if we could solve this problem without bumping the MSRV. I try to provide support for older versions of Rust, and Debian stable offers 1.63, which I'd like to continue to target.

[matthiasg]

This still happens on M1 with rust 1.78.0 nightly. Is there something I am missing ?

[ozgrakkurt]

still doesn't compile on m1 with stable toolchain with this error

[alamb]

Proposed fix #196

[djc]

FWIW, I'm running into this too (when trying to upgrade ahash in hickory-dns on my M1 with Rust 1.67).

[alexeykhan]

Same for me here (M1):

• rust 1.77.0-nightly - works fine
• rust 1.78.0-nightly - error[E0635]: unknown feature stdsimd
  --> /Users/alexeykhan/.cargo/registry/src/index.crates.io-6f17d22bba15001f/ahash-0.7.7/src/lib.rs:33:42
  |
  33 | #![cfg_attr(feature = "stdsimd", feature(stdsimd))]
  | ^^^^^^^

For more information about this error, try rustc --explain E0635.
error: could not compile ahash (lib) due to 1 previous error
warning: build failed, waiting for other jobs to finish...

[Amanieu]

Are you using the latest version of ahash? Try cargo update.

[tkaitchuck]

@Amanieu It looks like this is caused by #183
Should I revert it or is there a better way?

[Amanieu]

These functions are stable, are you using an older version of rustc?

[Anton-4]

Oh right, I didn't think to check that. I'm on 1.71.1. Would it be possible to set the required minimum version with the rust-version field in the Cargo.toml? That should provide a nice error message in this case.

[tkaitchuck]

I am attempting to expand the presubmit checks to cover this #197
but so far it is still passing. What combination am I missing?

[alamb]

What combination am I missing?

I left a suggestion: #197 (comment)

[tkaitchuck]

@Anton-4 Can you clearify, you saw this when targeting aarch64-apple-darwin ? What args / rust flags were passed?

[Jefffrey]

For datafusion, the issue came from apache/arrow-datafusion#8743

Tagging @Ted-Jiang who reproduced the issue

An example of the dependency datafusion has:

https://github.com/apache/arrow-datafusion/blob/e7cc04db68a05ce9d002de7d0c1be2644bf69c0c/datafusion/common/Cargo.toml#L41-L43

• Located in a few other crates within datafusion too, but is essentially the same (version & features)

[Anton-4]

Can you clearify, you saw this when targeting aarch64-apple-darwin ?

Yes indeed, I'll set up a minimal github repo with a full reproduction.

[Anton-4]

Files for minimal repro:

// rust-toolchain.toml 
[toolchain]
channel = "1.71.1"

// Cargo.toml 
[package]
name = "temp2"
version = "0.1.0"
edition = "2021"

[dependencies]
ahash="=0.8.7"

// src/main.rs 
fn main() {
    println!("Hello, world!");
}

run with cargo build --target=aarch64-apple-darwin.
That produces the error for me on NixOS (x86_64 device) and also on macos 14 (m2 device).

[iesahin]

I have the same issue in https://github.com/iesahin/xvc/actions/runs/7798376079/job/21266895940#step:9:1

[Amanieu]

To anyone hitting this error on nightly: you need to update your nightly compiler.

[undenuicap]

1.78.0-nightly is latest and not working with it :-(