[INFO] fetching crate polars 0.4.0...
[INFO] documenting polars-0.4.0 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate polars 0.4.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate polars 0.4.0 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate polars 0.4.0
[INFO] finished tweaking crates.io crate polars 0.4.0
[INFO] tweaked toml for crates.io crate polars 0.4.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 97cca44c9377aab2a403adea86f5cfbb5e11d79fa088abc52f5cd485e6e819a3
[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" "97cca44c9377aab2a403adea86f5cfbb5e11d79fa088abc52f5cd485e6e819a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "97cca44c9377aab2a403adea86f5cfbb5e11d79fa088abc52f5cd485e6e819a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "97cca44c9377aab2a403adea86f5cfbb5e11d79fa088abc52f5cd485e6e819a3", kill_on_drop: false }`
[INFO] [stdout] 97cca44c9377aab2a403adea86f5cfbb5e11d79fa088abc52f5cd485e6e819a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8d9cabbdf57faa27f344662ce8a2ef9d815d47445f403aa9c3219d59e8c7f4c1
[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" "8d9cabbdf57faa27f344662ce8a2ef9d815d47445f403aa9c3219d59e8c7f4c1", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling once_cell v1.4.1
[INFO] [stderr]     Checking unsafe_unwrap v0.1.0
[INFO] [stderr]     Checking flatbuffers v0.6.1
[INFO] [stderr]     Checking regex-automata v0.1.9
[INFO] [stderr]     Checking term v0.5.2
[INFO] [stderr]     Checking num-complex v0.2.4
[INFO] [stderr]     Checking num-bigint v0.2.6
[INFO] [stderr]     Checking chrono v0.4.15
[INFO] [stderr]    Compiling thiserror-impl v1.0.20
[INFO] [stderr]    Compiling enum_dispatch v0.3.2
[INFO] [stderr]     Checking prettytable-rs v0.8.0
[INFO] [stderr]     Checking num-rational v0.2.4
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]     Checking thiserror v1.0.20
[INFO] [stderr]     Checking bstr v0.2.13
[INFO] [stderr]     Checking serde_json v1.0.57
[INFO] [stderr]     Checking csv v1.1.3
[INFO] [stderr]     Checking arrow v1.0.1
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/arrow-1.0.1/src/lib.rs:24:1
[INFO] [stdout]    |
[INFO] [stdout] 24 | #![feature(specialization)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `arrow`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "8d9cabbdf57faa27f344662ce8a2ef9d815d47445f403aa9c3219d59e8c7f4c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d9cabbdf57faa27f344662ce8a2ef9d815d47445f403aa9c3219d59e8c7f4c1", kill_on_drop: false }`
[INFO] [stdout] 8d9cabbdf57faa27f344662ce8a2ef9d815d47445f403aa9c3219d59e8c7f4c1