[INFO] cloning repository https://github.com/frostRed/head_first_design_patterns_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/frostRed/head_first_design_patterns_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FfrostRed%2Fhead_first_design_patterns_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FfrostRed%2Fhead_first_design_patterns_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 779447adaf64ad62404312d51b8363b8602c3552
[INFO] documenting frostRed/head_first_design_patterns_rust 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%2FfrostRed%2Fhead_first_design_patterns_rust" "/workspace/builds/worker-10/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/frostRed/head_first_design_patterns_rust 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/frostRed/head_first_design_patterns_rust
[INFO] finished tweaking git repo https://github.com/frostRed/head_first_design_patterns_rust
[INFO] tweaked toml for git repo https://github.com/frostRed/head_first_design_patterns_rust written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate git repo https://github.com/frostRed/head_first_design_patterns_rust 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] fe45d7b126feec76efb8c8ccd162c7fbc4c918fc52eadb12b5aba293ee9d3b26
[INFO] running `Command { std: "docker" "start" "-a" "fe45d7b126feec76efb8c8ccd162c7fbc4c918fc52eadb12b5aba293ee9d3b26", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fe45d7b126feec76efb8c8ccd162c7fbc4c918fc52eadb12b5aba293ee9d3b26", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fe45d7b126feec76efb8c8ccd162c7fbc4c918fc52eadb12b5aba293ee9d3b26", kill_on_drop: false }`
[INFO] [stdout] fe45d7b126feec76efb8c8ccd162c7fbc4c918fc52eadb12b5aba293ee9d3b26
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] 6e17a09338c9fdd8e171ca21059c6feeb23b017a5d2bad0339585af4540e234d
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "6e17a09338c9fdd8e171ca21059c6feeb23b017a5d2bad0339585af4540e234d", kill_on_drop: false }`
[INFO] [stderr]  Documenting head_first_design_patterns v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary braces around block return value
[INFO] [stdout]   --> src/singleton.rs:50:49
[INFO] [stdout]    |
[INFO] [stdout] 50 |     pub static ref C: RwLock<ChocolateBoiler> = { RwLock::new(ChocolateBoiler::new()) };
[INFO] [stdout]    |                                                 ^^                                   ^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_braces)]` on by default
[INFO] [stdout] help: remove these braces
[INFO] [stdout]    |
[INFO] [stdout] 50 -     pub static ref C: RwLock<ChocolateBoiler> = { RwLock::new(ChocolateBoiler::new()) };
[INFO] [stdout] 50 +     pub static ref C: RwLock<ChocolateBoiler> = RwLock::new(ChocolateBoiler::new());
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_remove_item)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `vec_remove_item`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_remove_item)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `head_first_design_patterns`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name head_first_design_patterns src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=b76bcfbc43544893 -L dependency=/opt/rustwide/target/debug/deps --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-34beab4ed1f0a84e.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "6e17a09338c9fdd8e171ca21059c6feeb23b017a5d2bad0339585af4540e234d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e17a09338c9fdd8e171ca21059c6feeb23b017a5d2bad0339585af4540e234d", kill_on_drop: false }`
[INFO] [stdout] 6e17a09338c9fdd8e171ca21059c6feeb23b017a5d2bad0339585af4540e234d