[INFO] cloning repository https://github.com/binarybana/sudok
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/binarybana/sudok" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinarybana%2Fsudok", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinarybana%2Fsudok'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f6fa2f047974a83bf7c71b7f6b7f5e986ce2fc7a
[INFO] documenting binarybana/sudok against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinarybana%2Fsudok" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/binarybana/sudok on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/binarybana/sudok
[INFO] finished tweaking git repo https://github.com/binarybana/sudok
[INFO] tweaked toml for git repo https://github.com/binarybana/sudok written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/binarybana/sudok already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rayon v0.9.0
[INFO] [stderr]   Downloaded rayon-core v1.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6b2a47c52e777f4286288337702ef650b5cacc65beaa43f2aa4c65c5f8c52934
[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" "6b2a47c52e777f4286288337702ef650b5cacc65beaa43f2aa4c65c5f8c52934", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b2a47c52e777f4286288337702ef650b5cacc65beaa43f2aa4c65c5f8c52934", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b2a47c52e777f4286288337702ef650b5cacc65beaa43f2aa4c65c5f8c52934", kill_on_drop: false }`
[INFO] [stdout] 6b2a47c52e777f4286288337702ef650b5cacc65beaa43f2aa4c65c5f8c52934
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7d2db839f6fcaf6645f49f3a7ae35d5cebf50011d609dfc619d5844ae44430f4
[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" "7d2db839f6fcaf6645f49f3a7ae35d5cebf50011d609dfc619d5844ae44430f4", kill_on_drop: false }`
[INFO] [stderr]    Compiling rayon-core v1.3.0
[INFO] [stderr]     Checking either v1.4.0
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking num_cpus v1.7.0
[INFO] [stderr]     Checking rand v0.3.18
[INFO] [stderr]     Checking aho-corasick v0.6.4
[INFO] [stderr]     Checking coco v0.1.1
[INFO] [stderr]     Checking regex v0.2.3
[INFO] [stderr]     Checking rayon v0.9.0
[INFO] [stderr]     Checking env_logger v0.4.3
[INFO] [stderr]  Documenting sudok v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(nll)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `sudok`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type bin --crate-name sudok src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-6ef9eccdb034052a.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-e33c602b229ad16f.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-e8073698be3683f7.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-ffa8c27918135542.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "7d2db839f6fcaf6645f49f3a7ae35d5cebf50011d609dfc619d5844ae44430f4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d2db839f6fcaf6645f49f3a7ae35d5cebf50011d609dfc619d5844ae44430f4", kill_on_drop: false }`
[INFO] [stdout] 7d2db839f6fcaf6645f49f3a7ae35d5cebf50011d609dfc619d5844ae44430f4