error[E0635]: unknown feature `stdsimd`

[ArunGust]

unknown feature stdsimd : Got below after updating rust to new version rustc 1.78.0-nightly (f067fd608 2024-02-05)

error[E0635]: unknown feature stdsimd
--> C:\SYSTEM\RUST\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

[tusharmath]

Facing similar issue.

[tmpfs]

Same here on version 0.7.7, it's broken my crate's documentation build on docs.rs but works fine for me locally on Linux and MacOS, not sure why it's only broken in the docs.rs sandbox environment.

Here is the build log:

https://docs.rs/crate/sos-sdk/0.10.0/builds/1116456

[Kobzol]

This is caused by rust-lang/rust#117372. This problem in ahash was already fixed in #183, which was released in 0.8.7 (it just isn't visible as a GitHub release).

[RalfJung]

Fundamentally this is caused by logic in build.rs that auto-enables a nightly feature when it detects that it is built with a nightly rustc. Such logic is fragile and prone to errors as nightly features evolve before stabilization.

Crates should never automatically enable nightly features, this should generally be opt-in. If they try to do it automatically they need to be very careful and account for the fact that nightly features are not stable, and might look very different in future nightly versions.

I see aHash still does the same kind of auto-detection with the specialize feature. That's a similar issue just waiting to happen.

[humb1t]

Same for me

[mina86]

If you’re on 0.8 branch → update to 0.8.7. See #188.

However, I’m also picking up dependency on 0.7.7 through chain of older dependencies (borsh 0.9 → hashbrown 0.11 → ahash 0.7) which I can’t easily get rid of on my side. It’d be fantastic if we could get backport to 0.7 branch as well. I’ve commented that in #188.