[INFO] fetching crate polars_arrow_rvsry99dx 0.17.1...
[INFO] documenting polars_arrow_rvsry99dx-0.17.1 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate polars_arrow_rvsry99dx 0.17.1 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate polars_arrow_rvsry99dx 0.17.1 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 polars_arrow_rvsry99dx 0.17.1
[INFO] finished tweaking crates.io crate polars_arrow_rvsry99dx 0.17.1
[INFO] tweaked toml for crates.io crate polars_arrow_rvsry99dx 0.17.1 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate crates.io crate polars_arrow_rvsry99dx 0.17.1 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]     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 flatbuffers v0.6.1
[INFO] [stderr]   Downloaded packed_simd v0.3.3
[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] 8c3645525bd6d52fee6d50005b192462731ca01316f6b87e673c7a3170f27f1a
[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" "8c3645525bd6d52fee6d50005b192462731ca01316f6b87e673c7a3170f27f1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8c3645525bd6d52fee6d50005b192462731ca01316f6b87e673c7a3170f27f1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8c3645525bd6d52fee6d50005b192462731ca01316f6b87e673c7a3170f27f1a", kill_on_drop: false }`
[INFO] [stdout] 8c3645525bd6d52fee6d50005b192462731ca01316f6b87e673c7a3170f27f1a
[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] 5f4c8110adeb49ed50b0043242b7ed3bec93976e61c6c3e2b4af31a4910d6aed
[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" "5f4c8110adeb49ed50b0043242b7ed3bec93976e61c6c3e2b4af31a4910d6aed", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]    Compiling serde_json v1.0.55
[INFO] [stderr]    Compiling num-iter v0.1.41
[INFO] [stderr]     Checking flatbuffers v0.6.1
[INFO] [stderr]     Checking csv-core v0.1.10
[INFO] [stderr]     Checking dirs v1.0.5
[INFO] [stderr]     Checking num-complex v0.2.4
[INFO] [stderr]     Checking num-bigint v0.2.6
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]     Checking term v0.5.2
[INFO] [stderr]     Checking num-rational v0.2.4
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]     Checking bstr v0.2.13
[INFO] [stderr]     Checking csv v1.1.3
[INFO] [stderr]     Checking prettytable-rs v0.8.0
[INFO] [stderr]  Documenting polars_arrow_rvsry99dx v0.17.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:24:1
[INFO] [stdout]    |
[INFO] [stdout] 24 | #![feature(specialization)]
[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 `polars_arrow_rvsry99dx`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name polars_arrow_rvsry99dx src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="prettyprint"' --cfg 'feature="prettytable-rs"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern chrono=/opt/rustwide/target/debug/deps/libchrono-cf2b1f80ebca89c9.rmeta --extern csv=/opt/rustwide/target/debug/deps/libcsv-7677cf38b1055590.rmeta --extern flatbuffers=/opt/rustwide/target/debug/deps/libflatbuffers-de71eab29ee1604f.rmeta --extern hex=/opt/rustwide/target/debug/deps/libhex-b38b297ae8f34fd9.rmeta --extern indexmap=/opt/rustwide/target/debug/deps/libindexmap-9686da486af0b939.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-db88f49d9e5662e7.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-31b2b71a52eed8f8.rmeta --extern prettytable=/opt/rustwide/target/debug/deps/libprettytable-de162436da675495.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-c38880f5f03aa648.rmeta --extern regex=/opt/rustwide/target/debug/deps/libregex-c251ca4f1be2ef5d.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-533eeada33a5936c.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-99ab08bdefc991cc.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-1eb74cb1e239d133.rmeta --cap-lints=warn --crate-version 0.17.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "5f4c8110adeb49ed50b0043242b7ed3bec93976e61c6c3e2b4af31a4910d6aed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f4c8110adeb49ed50b0043242b7ed3bec93976e61c6c3e2b4af31a4910d6aed", kill_on_drop: false }`
[INFO] [stdout] 5f4c8110adeb49ed50b0043242b7ed3bec93976e61c6c3e2b4af31a4910d6aed