[INFO] cloning repository https://github.com/fisherdarling/maze_project
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/fisherdarling/maze_project" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffisherdarling%2Fmaze_project", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffisherdarling%2Fmaze_project'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c83fd51e56f360143ddfa4fdd77e492e100b5b42
[INFO] testing fisherdarling/maze_project against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffisherdarling%2Fmaze_project" "/workspace/builds/worker-114/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-114/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/fisherdarling/maze_project 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 git repo https://github.com/fisherdarling/maze_project
[INFO] finished tweaking git repo https://github.com/fisherdarling/maze_project
[INFO] tweaked toml for git repo https://github.com/fisherdarling/maze_project written to /workspace/builds/worker-114/source/Cargo.toml
[INFO] crate git repo https://github.com/fisherdarling/maze_project 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-114/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-114/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] e9ffa5f5c5a8aeceed2b5d80219bc8b34686f8fb6cb09b750d98d02057b1c042
[INFO] running `Command { std: "docker" "start" "-a" "e9ffa5f5c5a8aeceed2b5d80219bc8b34686f8fb6cb09b750d98d02057b1c042", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e9ffa5f5c5a8aeceed2b5d80219bc8b34686f8fb6cb09b750d98d02057b1c042", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9ffa5f5c5a8aeceed2b5d80219bc8b34686f8fb6cb09b750d98d02057b1c042", kill_on_drop: false }`
[INFO] [stdout] e9ffa5f5c5a8aeceed2b5d80219bc8b34686f8fb6cb09b750d98d02057b1c042
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-114/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-114/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] df53cadbd7d7d205317c06db23483a37e6638c97ddd69fb9bca15df663cf607e
[INFO] running `Command { std: "docker" "start" "-a" "df53cadbd7d7d205317c06db23483a37e6638c97ddd69fb9bca15df663cf607e", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.6
[INFO] [stderr]    Compiling syn v1.0.8
[INFO] [stderr]    Compiling ordermap v0.3.5
[INFO] [stderr]    Compiling fixedbitset v0.1.9
[INFO] [stderr]    Compiling text_io v0.1.7
[INFO] [stderr]    Compiling petgraph v0.4.13
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling derive_more v0.99.2
[INFO] [stderr]    Compiling maze_project v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/bin/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(slice_concat_trait)]
[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 `maze_project` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "df53cadbd7d7d205317c06db23483a37e6638c97ddd69fb9bca15df663cf607e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "df53cadbd7d7d205317c06db23483a37e6638c97ddd69fb9bca15df663cf607e", kill_on_drop: false }`
[INFO] [stdout] df53cadbd7d7d205317c06db23483a37e6638c97ddd69fb9bca15df663cf607e