compiling with simd-accel feature is broken due to removal of stdsimd feature in nightly breaking the packed_simd crate

[R-Goc]

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• I have a different issue.

What version of ripgrep are you using?

14.1

How did you install ripgrep?

Cargo
cargo +nightly install --force --profile "release" --features 'simd-accel' ripgrep

What operating system are you using ripgrep on?

Windows, though it affects all systems

Describe your bug.

The crate fails to compile with feature 'simd-accel' due to feature stdsimd being removed which broke packed_simd crate used for the 'simd-accel' feature. No impact on ripgrep otherwise. Only compiling with the feature isn't possible.
The commit that broke packed-simd is: rust-lang/rust@ea37e80
Relevant tracking issues: rust-lang/rust#27731 and rust-lang/rust#48556

What are the steps to reproduce the behavior?

Installing or compiling ripgrep with 'simd-accel' for example with:
cargo +nightly install --force --profile "release" --features 'simd-accel' ripgrep
target-cpu=native also has to be set.

What is the actual behavior?

cargo +nightly install --force --profile "release" --features 'simd-accel' ripgrep
Updating crates.io index
Installing ripgrep v14.1.0
Updating crates.io index
Downloaded packed_simd v0.3.9
Downloaded num-traits v0.2.18
Downloaded 2 crates (150.3 KB) in 0.58s
Compiling memchr v2.7.1
Compiling winapi v0.3.9
Compiling libm v0.2.8
Compiling regex-syntax v0.8.2
Compiling autocfg v1.1.0
Compiling packed_simd v0.3.9
Compiling log v0.4.20
Compiling cfg-if v1.0.0
Compiling serde v1.0.196
Compiling crossbeam-utils v0.8.19
Compiling num-traits v0.2.18
Compiling aho-corasick v1.1.2
Compiling grep-matcher v0.1.7
Compiling serde_json v1.0.113
Compiling itoa v1.0.10
Compiling ryu v1.0.16
Compiling memmap2 v0.9.4
Compiling crossbeam-epoch v0.9.18
Compiling anyhow v1.0.79
Compiling winapi-util v0.1.6
Compiling crossbeam-deque v0.8.5
Compiling ripgrep v14.1.0
Compiling termcolor v1.4.1
Compiling same-file v1.0.6
Compiling walkdir v2.4.0
Compiling textwrap v0.16.0
Compiling lexopt v0.3.0
Compiling regex-automata v0.4.5
error[E0635]: unknown feature stdsimd
--> .cargo\registry\src\index.crates.io-6f17d22bba15001f\packed_simd-0.3.9\src\lib.rs:219:5
|
219 | stdsimd,
| ^^^^^^^

For more information about this error, try rustc --explain E0635.
error: could not compile packed_simd (lib) due to 1 previous error

What is the expected behavior?

should compile with the feature enabled.

[BurntSushi]

I don't think this needs to be tracked here. It's a nightly feature anyway and will get fixed once packed_simd is fixed.