[INFO] cloning repository https://github.com/brian-dawn/advent-of-code-2020
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/brian-dawn/advent-of-code-2020" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrian-dawn%2Fadvent-of-code-2020", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrian-dawn%2Fadvent-of-code-2020'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4c50fba034162becea25dae21e9c32def9ad47ac
[INFO] testing brian-dawn/advent-of-code-2020 against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrian-dawn%2Fadvent-of-code-2020" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/brian-dawn/advent-of-code-2020 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] removed /workspace/builds/worker-12/source/rust-toolchain
[INFO] started tweaking git repo https://github.com/brian-dawn/advent-of-code-2020
[INFO] finished tweaking git repo https://github.com/brian-dawn/advent-of-code-2020
[INFO] tweaked toml for git repo https://github.com/brian-dawn/advent-of-code-2020 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/brian-dawn/advent-of-code-2020 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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] b7c7157d1ed4d244a610f33a2f18eafc62959531ec4e3f309cf9ea1ff65ebb3d
[INFO] running `Command { std: "docker" "start" "-a" "b7c7157d1ed4d244a610f33a2f18eafc62959531ec4e3f309cf9ea1ff65ebb3d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b7c7157d1ed4d244a610f33a2f18eafc62959531ec4e3f309cf9ea1ff65ebb3d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b7c7157d1ed4d244a610f33a2f18eafc62959531ec4e3f309cf9ea1ff65ebb3d", kill_on_drop: false }`
[INFO] [stdout] b7c7157d1ed4d244a610f33a2f18eafc62959531ec4e3f309cf9ea1ff65ebb3d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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] 81b6022613eabf7ce737ef1c50fc1abb58d34bedb1eb7e11a6ac2ec579c00cf1
[INFO] running `Command { std: "docker" "start" "-a" "81b6022613eabf7ce737ef1c50fc1abb58d34bedb1eb7e11a6ac2ec579c00cf1", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling syn v1.0.53
[INFO] [stderr]    Compiling regex-syntax v0.6.21
[INFO] [stderr]    Compiling once_cell v1.5.2
[INFO] [stderr]    Compiling anyhow v1.0.34
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling aho-corasick v0.7.15
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling regex v1.4.2
[INFO] [stderr]    Compiling parse-display-derive v0.4.0
[INFO] [stderr]    Compiling parse-display v0.4.0
[INFO] [stderr]    Compiling advent-of-code-2020 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/bin/day6.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_fold_self)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `fold_first` found for struct `Map` in the current scope
[INFO] [stdout]   --> src/bin/day6.rs:36:18
[INFO] [stdout]    |
[INFO] [stdout] 36 |                 .fold_first(|acc, val| combine_fn(&acc, &val))
[INFO] [stdout]    |                  ^^^^^^^^^^ method not found in `Map<std::slice::Iter<'_, String>, [closure@src/bin/day6.rs:35:22: 35:65]>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `advent-of-code-2020` due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "81b6022613eabf7ce737ef1c50fc1abb58d34bedb1eb7e11a6ac2ec579c00cf1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "81b6022613eabf7ce737ef1c50fc1abb58d34bedb1eb7e11a6ac2ec579c00cf1", kill_on_drop: false }`
[INFO] [stdout] 81b6022613eabf7ce737ef1c50fc1abb58d34bedb1eb7e11a6ac2ec579c00cf1