[INFO] fetching crate ak 0.1.1...
[INFO] testing ak-0.1.1 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate ak 0.1.1 into /workspace/builds/worker-48/source
[INFO] validating manifest of crates.io crate ak 0.1.1 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ak 0.1.1
[INFO] finished tweaking crates.io crate ak 0.1.1
[INFO] tweaked toml for crates.io crate ak 0.1.1 written to /workspace/builds/worker-48/source/Cargo.toml
[INFO] crate crates.io crate ak 0.1.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-48/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-48/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7b769137789323ba3d2239411f974f66eaf7d11d2cb69cb61308519da24ae553
[INFO] running `Command { std: "docker" "start" "-a" "7b769137789323ba3d2239411f974f66eaf7d11d2cb69cb61308519da24ae553", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7b769137789323ba3d2239411f974f66eaf7d11d2cb69cb61308519da24ae553", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7b769137789323ba3d2239411f974f66eaf7d11d2cb69cb61308519da24ae553", kill_on_drop: false }`
[INFO] [stdout] 7b769137789323ba3d2239411f974f66eaf7d11d2cb69cb61308519da24ae553
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-48/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-48/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 21031e4ea9f7157be10663c8ece9d51e9aa1f0216a8d164443333df263413ee0
[INFO] running `Command { std: "docker" "start" "-a" "21031e4ea9f7157be10663c8ece9d51e9aa1f0216a8d164443333df263413ee0", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.5
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]    Compiling libc v0.2.62
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling slab v0.4.2
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling pin-utils v0.1.0-alpha.4
[INFO] [stderr]    Compiling ak-rt v0.1.0
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling num_cpus v1.10.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling proc-macro-hack v0.5.10
[INFO] [stderr]    Compiling ak-codegen v0.1.0
[INFO] [stderr]    Compiling async-trait v0.1.13
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/ak-codegen-0.1.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_syntax)]
[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 `ak-codegen` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "21031e4ea9f7157be10663c8ece9d51e9aa1f0216a8d164443333df263413ee0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21031e4ea9f7157be10663c8ece9d51e9aa1f0216a8d164443333df263413ee0", kill_on_drop: false }`
[INFO] [stdout] 21031e4ea9f7157be10663c8ece9d51e9aa1f0216a8d164443333df263413ee0