[INFO] fetching crate fart-cli 0.4.0...
[INFO] documenting fart-cli-0.4.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate fart-cli 0.4.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate fart-cli 0.4.0 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 crates.io crate fart-cli 0.4.0
[INFO] finished tweaking crates.io crate fart-cli 0.4.0
[INFO] tweaked toml for crates.io crate fart-cli 0.4.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate fart-cli 0.4.0 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 tide v0.4.0
[INFO] [stderr]   Downloaded async-std 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] d73bdff4e5a70cd03cacedd0169c48d1396aa044d012876a72f639aee9608f44
[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" "d73bdff4e5a70cd03cacedd0169c48d1396aa044d012876a72f639aee9608f44", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d73bdff4e5a70cd03cacedd0169c48d1396aa044d012876a72f639aee9608f44", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d73bdff4e5a70cd03cacedd0169c48d1396aa044d012876a72f639aee9608f44", kill_on_drop: false }`
[INFO] [stdout] d73bdff4e5a70cd03cacedd0169c48d1396aa044d012876a72f639aee9608f44
[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] 09616bd417b6b224aaf7691d4742d3678385d80be57600f763553f882a81d0be
[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" "09616bd417b6b224aaf7691d4742d3678385d80be57600f763553f882a81d0be", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking once_cell v1.2.0
[INFO] [stderr]     Checking same-file v1.0.5
[INFO] [stderr]     Checking data-encoding v2.1.2
[INFO] [stderr]     Checking route-recognizer v0.1.13
[INFO] [stderr]     Checking async-task v1.0.0
[INFO] [stderr]     Checking inotify-sys v0.1.3
[INFO] [stderr]     Checking atty v0.2.13
[INFO] [stderr]     Checking filetime v0.2.8
[INFO] [stderr]    Compiling hyper v0.12.35
[INFO] [stderr]     Checking want v0.2.0
[INFO] [stderr]     Checking futures-cpupool v0.1.8
[INFO] [stderr]     Checking tokio-io v0.1.12
[INFO] [stderr]     Checking http v0.1.21
[INFO] [stderr]     Checking mio-extras v2.0.6
[INFO] [stderr]     Checking error-chain v0.12.1
[INFO] [stderr]     Checking walkdir v2.2.9
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking parking_lot v0.9.0
[INFO] [stderr]     Checking inotify v0.6.1
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking tokio-threadpool v0.1.17
[INFO] [stderr]     Checking notify v4.0.14
[INFO] [stderr]     Checking tokio-reactor v0.1.11
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]     Checking tokio-tcp v0.1.3
[INFO] [stderr]     Checking broadcaster v0.2.6
[INFO] [stderr]     Checking h2 v0.1.26
[INFO] [stderr]     Checking http-body v0.1.0
[INFO] [stderr]     Checking async-std v1.3.0
[INFO] [stderr]    Compiling proc-macro-error v0.2.6
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling proc-macro-hack v0.5.11
[INFO] [stderr]    Compiling serde_derive v1.0.104
[INFO] [stderr]    Compiling structopt-derive v0.3.5
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]     Checking failure v0.1.6
[INFO] [stderr]    Compiling futures-macro v0.3.1
[INFO] [stderr]     Checking structopt v0.3.5
[INFO] [stderr]     Checking futures-util v0.3.1
[INFO] [stderr]     Checking serde v1.0.104
[INFO] [stderr]     Checking futures-executor v0.3.1
[INFO] [stderr]     Checking futures v0.3.1
[INFO] [stderr]     Checking http-service v0.4.0
[INFO] [stderr]     Checking http-service-hyper v0.4.1
[INFO] [stderr]     Checking serde_json v1.0.44
[INFO] [stderr]     Checking serde_qs v0.5.2
[INFO] [stderr]     Checking tide v0.4.0
[INFO] [stderr]  Documenting fart-cli v0.4.0 (/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(async_closure)]
[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 `fart-cli`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name fart 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 async_std=/opt/rustwide/target/debug/deps/libasync_std-9fa6975cbfd850a2.rmeta --extern bytes=/opt/rustwide/target/debug/deps/libbytes-de51493f3ad5e5ad.rmeta --extern chrono=/opt/rustwide/target/debug/deps/libchrono-62f9ecf24b9f8047.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-33e97f8dcef89fa6.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-55fc73bee632c288.rmeta --extern http_service=/opt/rustwide/target/debug/deps/libhttp_service-72d316e72e06385e.rmeta --extern notify=/opt/rustwide/target/debug/deps/libnotify-d2458b55eb40716d.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-3cb8675be060ab34.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-b0739305cebe59b6.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-d566dcf6a7fa36f7.rmeta --extern tide=/opt/rustwide/target/debug/deps/libtide-70f106dba47098f5.rmeta --cap-lints=warn --crate-version 0.4.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "09616bd417b6b224aaf7691d4742d3678385d80be57600f763553f882a81d0be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "09616bd417b6b224aaf7691d4742d3678385d80be57600f763553f882a81d0be", kill_on_drop: false }`
[INFO] [stdout] 09616bd417b6b224aaf7691d4742d3678385d80be57600f763553f882a81d0be