[INFO] fetching crate cow_vec_item 0.5.1...
[INFO] testing cow_vec_item-0.5.1 against beta-2022-02-22 for beta-1.60-1
[INFO] extracting crate cow_vec_item 0.5.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate cow_vec_item 0.5.1 on toolchain beta-2022-02-22
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-02-22" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cow_vec_item 0.5.1
[INFO] finished tweaking crates.io crate cow_vec_item 0.5.1
[INFO] tweaked toml for crates.io crate cow_vec_item 0.5.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-02-22" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-02-22" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2ec90db58325a1b51ce836b36aec791473af0e59c5e0ddafa593aa6efe99818e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2ec90db58325a1b51ce836b36aec791473af0e59c5e0ddafa593aa6efe99818e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2ec90db58325a1b51ce836b36aec791473af0e59c5e0ddafa593aa6efe99818e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ec90db58325a1b51ce836b36aec791473af0e59c5e0ddafa593aa6efe99818e", kill_on_drop: false }`
[INFO] [stdout] 2ec90db58325a1b51ce836b36aec791473af0e59c5e0ddafa593aa6efe99818e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c6f907627c48f3a29829f73565b9976d7bcb77e4cb8a8cb55a6a76e6b24eae1d
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c6f907627c48f3a29829f73565b9976d7bcb77e4cb8a8cb55a6a76e6b24eae1d", kill_on_drop: false }`
[INFO] [stderr]    Compiling cow_vec_item v0.5.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.17s
[INFO] running `Command { std: "docker" "inspect" "c6f907627c48f3a29829f73565b9976d7bcb77e4cb8a8cb55a6a76e6b24eae1d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6f907627c48f3a29829f73565b9976d7bcb77e4cb8a8cb55a6a76e6b24eae1d", kill_on_drop: false }`
[INFO] [stdout] c6f907627c48f3a29829f73565b9976d7bcb77e4cb8a8cb55a6a76e6b24eae1d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1122d4ee5d36e0502d5c7ec004b249986d0237bf551cc3f629d28fe219854597
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "1122d4ee5d36e0502d5c7ec004b249986d0237bf551cc3f629d28fe219854597", kill_on_drop: false }`
[INFO] [stderr]    Compiling cow_vec_item v0.5.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:3:27
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![cfg_attr(test, feature(test))]
[INFO] [stdout]   |                           ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `cow_vec_item` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "1122d4ee5d36e0502d5c7ec004b249986d0237bf551cc3f629d28fe219854597", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1122d4ee5d36e0502d5c7ec004b249986d0237bf551cc3f629d28fe219854597", kill_on_drop: false }`
[INFO] [stdout] 1122d4ee5d36e0502d5c7ec004b249986d0237bf551cc3f629d28fe219854597