regression: `#![feature]` may not be used on the beta release channel

[BoxyUwU]

• https://crater-reports.s3.amazonaws.com/beta-1.88-1/beta-2025-05-26/gh/daniestevez.qsdr/log.txt

[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/git/checkouts/futuresdr-f0f4c1cb7e3a1548/0caf989/crates/futuredsp/src/lib.rs:5:35
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![cfg_attr(not(RUSTC_IS_STABLE), feature(core_intrinsics))]
[INFO] [stdout]   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^

cc @jdonszelmann does this have anything to do with ur attribute handling stuff potentially

[bjorn3]

This crate literally only enables RUSTC_IS_STABLE when on the stable channel. If you are on the beta channel it will set RUSTC_IS_BETA instead, thus causing it to use nightly features 🤦

[apiraino]

This crate literally only enables RUSTC_IS_STABLE when on the stable channel. If you are on the beta channel it will set RUSTC_IS_BETA instead, thus causing it to use nightly features 🤦

I wonder why was this crate included in the test suite 🤔

[workingjubilee]

Because we did not deliberately exclude it. It should probably be added to the crater exclusions.

[BoxyUwU]

Yeah we crater everything by default, this crate should be excluded