[INFO] cloning repository https://github.com/hfcredidio/aoc_2020
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/hfcredidio/aoc_2020" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhfcredidio%2Faoc_2020", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhfcredidio%2Faoc_2020'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6d383047782ceea59e53e308037e610f7737b7ca
[INFO] testing hfcredidio/aoc_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%2Fhfcredidio%2Faoc_2020" "/workspace/builds/worker-91/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-91/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/hfcredidio/aoc_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] started tweaking git repo https://github.com/hfcredidio/aoc_2020
[INFO] finished tweaking git repo https://github.com/hfcredidio/aoc_2020
[INFO] tweaked toml for git repo https://github.com/hfcredidio/aoc_2020 written to /workspace/builds/worker-91/source/Cargo.toml
[INFO] crate git repo https://github.com/hfcredidio/aoc_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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-91/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-91/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] b9706976e4b6c3a22a46a0a4bc745c916fc7c316649095a5bd9aa4fdcf5ce297
[INFO] running `Command { std: "docker" "start" "-a" "b9706976e4b6c3a22a46a0a4bc745c916fc7c316649095a5bd9aa4fdcf5ce297", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b9706976e4b6c3a22a46a0a4bc745c916fc7c316649095a5bd9aa4fdcf5ce297", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9706976e4b6c3a22a46a0a4bc745c916fc7c316649095a5bd9aa4fdcf5ce297", kill_on_drop: false }`
[INFO] [stdout] b9706976e4b6c3a22a46a0a4bc745c916fc7c316649095a5bd9aa4fdcf5ce297
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-91/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-91/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] f1a59eab9000938ebfcde78c5ed0c27c712af9e53e20113095886b0c935a6f2b
[INFO] running `Command { std: "docker" "start" "-a" "f1a59eab9000938ebfcde78c5ed0c27c712af9e53e20113095886b0c935a6f2b", kill_on_drop: false }`
[INFO] [stderr]    Compiling aoc_2020 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(iterator_fold_self)]
[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(peekable_next_if)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `fold_first` found for struct `Filter` in the current scope
[INFO] [stdout]   --> src/day16.rs:98:10
[INFO] [stdout]    |
[INFO] [stdout] 98 |         .fold_first(|acc, fields| {
[INFO] [stdout]    |          ^^^^^^^^^^ method not found in `Filter<Map<std::slice::Iter<'_, Vec<u64>>, [closure@src/day16.rs:91:14: 96:10]>, [closure@src/day16.rs:97:17: 97:76]>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `fold_first` found for struct `Map` in the current scope
[INFO] [stdout]   --> src/day6.rs:13:10
[INFO] [stdout]    |
[INFO] [stdout] 13 |         .fold_first(|acc, x| acc.intersection(&x).copied().collect())
[INFO] [stdout]    |          ^^^^^^^^^^ method not found in `Map<std::str::Lines<'_>, for<'r> fn(&'r str) -> HashSet<char> {unique_chars}>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 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 `aoc_2020` due to 5 previous errors
[INFO] running `Command { std: "docker" "inspect" "f1a59eab9000938ebfcde78c5ed0c27c712af9e53e20113095886b0c935a6f2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f1a59eab9000938ebfcde78c5ed0c27c712af9e53e20113095886b0c935a6f2b", kill_on_drop: false }`
[INFO] [stdout] f1a59eab9000938ebfcde78c5ed0c27c712af9e53e20113095886b0c935a6f2b