[INFO] fetching crate jn 0.1.0...
[INFO] testing jn-0.1.0 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate jn 0.1.0 into /workspace/builds/worker-53/source
[INFO] validating manifest of crates.io crate jn 0.1.0 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-53/source/rust-toolchain
[INFO] started tweaking crates.io crate jn 0.1.0
[INFO] finished tweaking crates.io crate jn 0.1.0
[INFO] tweaked toml for crates.io crate jn 0.1.0 written to /workspace/builds/worker-53/source/Cargo.toml
[INFO] crate crates.io crate jn 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded hostname v0.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-53/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-53/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2d43ad06db2828944d9b21c6f8a37a5725e0b120593891a39c0d313b0a68af28
[INFO] running `Command { std: "docker" "start" "-a" "2d43ad06db2828944d9b21c6f8a37a5725e0b120593891a39c0d313b0a68af28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2d43ad06db2828944d9b21c6f8a37a5725e0b120593891a39c0d313b0a68af28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2d43ad06db2828944d9b21c6f8a37a5725e0b120593891a39c0d313b0a68af28", kill_on_drop: false }`
[INFO] [stdout] 2d43ad06db2828944d9b21c6f8a37a5725e0b120593891a39c0d313b0a68af28
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-53/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-53/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7a541bc67c690415748a08f95bfe5130de2ab6db95ab5bb4d4827ff2a0edd199
[INFO] running `Command { std: "docker" "start" "-a" "7a541bc67c690415748a08f95bfe5130de2ab6db95ab5bb4d4827ff2a0edd199", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.14
[INFO] [stderr]    Compiling itoa v0.4.5
[INFO] [stderr]    Compiling match_cfg v0.1.0
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling num-integer v0.1.42
[INFO] [stderr]    Compiling dirs-sys v0.3.4
[INFO] [stderr]    Compiling hostname v0.3.0
[INFO] [stderr]    Compiling dirs v2.0.2
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling serde_json v1.0.48
[INFO] [stderr]    Compiling chrono v0.4.10
[INFO] [stderr]    Compiling jn v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(map_first_last)]
[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 `jn` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "7a541bc67c690415748a08f95bfe5130de2ab6db95ab5bb4d4827ff2a0edd199", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7a541bc67c690415748a08f95bfe5130de2ab6db95ab5bb4d4827ff2a0edd199", kill_on_drop: false }`
[INFO] [stdout] 7a541bc67c690415748a08f95bfe5130de2ab6db95ab5bb4d4827ff2a0edd199
