[INFO] cloning repository https://github.com/Alt-64/advent2021
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Alt-64/advent2021" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAlt-64%2Fadvent2021", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAlt-64%2Fadvent2021'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] abab97c90e342c043aab4f11fa5b809d1bbe8558
[INFO] documenting Alt-64/advent2021 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAlt-64%2Fadvent2021" "/workspace/builds/worker-36/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-36/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Alt-64/advent2021 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Alt-64/advent2021
[INFO] finished tweaking git repo https://github.com/Alt-64/advent2021
[INFO] tweaked toml for git repo https://github.com/Alt-64/advent2021 written to /workspace/builds/worker-36/source/Cargo.toml
[INFO] crate git repo https://github.com/Alt-64/advent2021 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "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 test-case v1.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6af9ce2c93e9c2570ea12a08eee0d2aef6b62924eb9cfce0cbc9bcd82b9fd986
[INFO] running `Command { std: "docker" "start" "-a" "6af9ce2c93e9c2570ea12a08eee0d2aef6b62924eb9cfce0cbc9bcd82b9fd986", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6af9ce2c93e9c2570ea12a08eee0d2aef6b62924eb9cfce0cbc9bcd82b9fd986", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6af9ce2c93e9c2570ea12a08eee0d2aef6b62924eb9cfce0cbc9bcd82b9fd986", kill_on_drop: false }`
[INFO] [stdout] 6af9ce2c93e9c2570ea12a08eee0d2aef6b62924eb9cfce0cbc9bcd82b9fd986
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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" "RUSTDOCFLAGS=--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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c81cbf521c023afcbc6a4cdca960e25ad22a8f79860bb827303ce0aeee9c43b6
[INFO] running `Command { std: "docker" "start" "-a" "c81cbf521c023afcbc6a4cdca960e25ad22a8f79860bb827303ce0aeee9c43b6", kill_on_drop: false }`
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.3
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]  Documenting advent2021 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(custom_test_frameworks)]
[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(iterator_try_reduce)]
[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(hash_drain_filter)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(array_zip)]
[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:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(slice_as_chunks)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(let_chains)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 7 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 document `advent2021`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2021 --crate-type bin --crate-name advent2021 src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=2828fedca5765487 -L dependency=/opt/rustwide/target/debug/deps --extern bitflags=/opt/rustwide/target/debug/deps/libbitflags-22d7f70832a3b85e.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-ce054685ebb35006.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "c81cbf521c023afcbc6a4cdca960e25ad22a8f79860bb827303ce0aeee9c43b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c81cbf521c023afcbc6a4cdca960e25ad22a8f79860bb827303ce0aeee9c43b6", kill_on_drop: false }`
[INFO] [stdout] c81cbf521c023afcbc6a4cdca960e25ad22a8f79860bb827303ce0aeee9c43b6