[INFO] fetching crate irclap 0.1.0...
[INFO] documenting irclap-0.1.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate irclap 0.1.0 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate irclap 0.1.0 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 irclap 0.1.0
[INFO] finished tweaking crates.io crate irclap 0.1.0
[INFO] tweaked toml for crates.io crate irclap 0.1.0 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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 tokio-mockstream v1.1.0
[INFO] [stderr]   Downloaded irc v0.13.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] dcf0986adc6377ad4d1f889920ee596837be0c0bbcdf54bc9606211c052684aa
[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" "dcf0986adc6377ad4d1f889920ee596837be0c0bbcdf54bc9606211c052684aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dcf0986adc6377ad4d1f889920ee596837be0c0bbcdf54bc9606211c052684aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dcf0986adc6377ad4d1f889920ee596837be0c0bbcdf54bc9606211c052684aa", kill_on_drop: false }`
[INFO] [stdout] dcf0986adc6377ad4d1f889920ee596837be0c0bbcdf54bc9606211c052684aa
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] 89d8a9c37af58c05707947c1a7455152df99fcad2521e29bbbe5da24b8cfe7b7
[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" "89d8a9c37af58c05707947c1a7455152df99fcad2521e29bbbe5da24b8cfe7b7", kill_on_drop: false }`
[INFO] [stderr]     Checking encoding_index_tests v0.1.4
[INFO] [stderr]     Checking bufstream v0.1.4
[INFO] [stderr]     Checking tokio-timer v0.1.2
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking tokio-tls v0.2.1
[INFO] [stderr]     Checking tokio-mockstream v1.1.0
[INFO] [stderr]     Checking encoding-index-tradchinese v1.20141219.5
[INFO] [stderr]     Checking encoding-index-korean v1.20141219.5
[INFO] [stderr]     Checking encoding-index-singlebyte v1.20141219.5
[INFO] [stderr]     Checking encoding-index-simpchinese v1.20141219.5
[INFO] [stderr]     Checking encoding-index-japanese v1.20141219.5
[INFO] [stderr]     Checking encoding v0.2.33
[INFO] [stderr]     Checking irc v0.13.6
[INFO] [stderr]  Documenting irclap v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #![feature(conservative_impl_trait)]
[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 `irclap`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name irclap src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern clap=/opt/rustwide/target/debug/deps/libclap-1c9c629b2fe91003.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-f6a782863e1804d0.rmeta --extern irc=/opt/rustwide/target/debug/deps/libirc-5863bb6bb3ee9d42.rmeta --extern tokio_core=/opt/rustwide/target/debug/deps/libtokio_core-ff03024f6ac3d463.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "89d8a9c37af58c05707947c1a7455152df99fcad2521e29bbbe5da24b8cfe7b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89d8a9c37af58c05707947c1a7455152df99fcad2521e29bbbe5da24b8cfe7b7", kill_on_drop: false }`
[INFO] [stdout] 89d8a9c37af58c05707947c1a7455152df99fcad2521e29bbbe5da24b8cfe7b7