[INFO] cloning repository https://github.com/andreluecke/adventofcode2020
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/andreluecke/adventofcode2020" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandreluecke%2Fadventofcode2020", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandreluecke%2Fadventofcode2020'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 761237756b80ec65e2b39a0edc177f0e6cd0578f
[INFO] testing andreluecke/adventofcode2020 against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandreluecke%2Fadventofcode2020" "/workspace/builds/worker-72/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-72/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/andreluecke/adventofcode2020 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/andreluecke/adventofcode2020
[INFO] finished tweaking git repo https://github.com/andreluecke/adventofcode2020
[INFO] tweaked toml for git repo https://github.com/andreluecke/adventofcode2020 written to /workspace/builds/worker-72/source/Cargo.toml
[INFO] crate git repo https://github.com/andreluecke/adventofcode2020 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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 reduce v0.1.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/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" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2d8f578e81d024cea3e68b9e430dcded5fce853bab3b2ab8ce54260d2cc6ce4b
[INFO] running `Command { std: "docker" "start" "-a" "2d8f578e81d024cea3e68b9e430dcded5fce853bab3b2ab8ce54260d2cc6ce4b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2d8f578e81d024cea3e68b9e430dcded5fce853bab3b2ab8ce54260d2cc6ce4b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2d8f578e81d024cea3e68b9e430dcded5fce853bab3b2ab8ce54260d2cc6ce4b", kill_on_drop: false }`
[INFO] [stdout] 2d8f578e81d024cea3e68b9e430dcded5fce853bab3b2ab8ce54260d2cc6ce4b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-72/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" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5ddf8534a83db1047ebae00696a5650fe4564d2d3c12c1ea57dad4020e98f32a
[INFO] running `Command { std: "docker" "start" "-a" "5ddf8534a83db1047ebae00696a5650fe4564d2d3c12c1ea57dad4020e98f32a", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling regex-syntax v0.6.21
[INFO] [stderr]    Compiling bit-vec v0.6.3
[INFO] [stderr]    Compiling reduce v0.1.3
[INFO] [stderr]    Compiling thread_local v1.0.1
[INFO] [stderr]    Compiling aho-corasick v0.7.15
[INFO] [stderr]    Compiling regex v1.4.2
[INFO] [stderr]    Compiling adventofcode2020 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(option_result_contains)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(iter_advance_by)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(str_split_once)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `adventofcode2020` due to 4 previous errors
[INFO] running `Command { std: "docker" "inspect" "5ddf8534a83db1047ebae00696a5650fe4564d2d3c12c1ea57dad4020e98f32a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ddf8534a83db1047ebae00696a5650fe4564d2d3c12c1ea57dad4020e98f32a", kill_on_drop: false }`
[INFO] [stdout] 5ddf8534a83db1047ebae00696a5650fe4564d2d3c12c1ea57dad4020e98f32a