[INFO] fetching crate rust-ukf 0.1.0...
[INFO] testing rust-ukf-0.1.0 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate rust-ukf 0.1.0 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate rust-ukf 0.1.0
[INFO] finished tweaking crates.io crate rust-ukf 0.1.0
[INFO] tweaked toml for crates.io crate rust-ukf 0.1.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate rust-ukf 0.1.0 on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate rust-ukf 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a6c271ee825bb400d2f8b3e7baebf2b81a154f0f60f0272b0f59d5ee13a9a8c8
[INFO] running `Command { std: "docker" "start" "-a" "a6c271ee825bb400d2f8b3e7baebf2b81a154f0f60f0272b0f59d5ee13a9a8c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a6c271ee825bb400d2f8b3e7baebf2b81a154f0f60f0272b0f59d5ee13a9a8c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a6c271ee825bb400d2f8b3e7baebf2b81a154f0f60f0272b0f59d5ee13a9a8c8", kill_on_drop: false }`
[INFO] [stdout] a6c271ee825bb400d2f8b3e7baebf2b81a154f0f60f0272b0f59d5ee13a9a8c8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 13f886f755c08bf3dce17a0b8ae84a40f45d936a78fba5137dcd27b52004e0bb
[INFO] running `Command { std: "docker" "start" "-a" "13f886f755c08bf3dce17a0b8ae84a40f45d936a78fba5137dcd27b52004e0bb", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.43
[INFO] [stderr]    Compiling unicode-ident v1.0.3
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling syn v1.0.99
[INFO] [stderr]    Compiling bytemuck v1.12.1
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]    Compiling paste v1.0.9
[INFO] [stderr]    Compiling rawpointer v0.2.1
[INFO] [stderr]    Compiling matrixmultiply v0.3.2
[INFO] [stderr]    Compiling safe_arch v0.6.0
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling num-rational v0.4.1
[INFO] [stderr]    Compiling wide v0.7.4
[INFO] [stderr]    Compiling num-complex v0.4.2
[INFO] [stderr]    Compiling approx v0.5.1
[INFO] [stderr]    Compiling simba v0.7.2
[INFO] [stderr]    Compiling nalgebra-macros v0.1.0
[INFO] [stderr]    Compiling nalgebra v0.30.1
[INFO] [stderr]    Compiling rust-ukf v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | #![feature(generic_const_exprs)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `generic_const_exprs` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]   --> src/lib.rs:14:12
[INFO] [stdout]    |
[INFO] [stdout] 14 | #![feature(generic_const_exprs)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #76560 <https://github.com/rust-lang/rust/issues/76560> for more information
[INFO] [stdout]    = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-ukf` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "13f886f755c08bf3dce17a0b8ae84a40f45d936a78fba5137dcd27b52004e0bb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "13f886f755c08bf3dce17a0b8ae84a40f45d936a78fba5137dcd27b52004e0bb", kill_on_drop: false }`
[INFO] [stdout] 13f886f755c08bf3dce17a0b8ae84a40f45d936a78fba5137dcd27b52004e0bb
