[INFO] fetching crate math 0.8.8...
[INFO] documenting math-0.8.8 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate math 0.8.8 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate math 0.8.8 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate math 0.8.8
[INFO] finished tweaking crates.io crate math 0.8.8
[INFO] tweaked toml for crates.io crate math 0.8.8 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a9d01c5e275a64b06aa2494ad50949721e219a7c019017246d78fca19a136fc5
[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" "a9d01c5e275a64b06aa2494ad50949721e219a7c019017246d78fca19a136fc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a9d01c5e275a64b06aa2494ad50949721e219a7c019017246d78fca19a136fc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a9d01c5e275a64b06aa2494ad50949721e219a7c019017246d78fca19a136fc5", kill_on_drop: false }`
[INFO] [stdout] a9d01c5e275a64b06aa2494ad50949721e219a7c019017246d78fca19a136fc5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 98f5a3804302b7125249e0b958248068fb1703a30f99e419dc28861d78b004ad
[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" "98f5a3804302b7125249e0b958248068fb1703a30f99e419dc28861d78b004ad", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]     Checking num-integer v0.1.43
[INFO] [stderr]     Checking num-complex v0.2.4
[INFO] [stderr]     Checking num-bigint v0.2.6
[INFO] [stderr]     Checking num-iter v0.1.41
[INFO] [stderr]     Checking num-rational v0.2.4
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]  Documenting math v0.8.8 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(bool_to_option)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `math`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name math 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 log=/opt/rustwide/target/debug/deps/liblog-4d9b6dc7228ae14f.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-587bf9e351ade784.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-c85954dc41156076.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-8d823b7f65145b73.rmeta --cap-lints=warn --crate-version 0.8.8` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "98f5a3804302b7125249e0b958248068fb1703a30f99e419dc28861d78b004ad", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98f5a3804302b7125249e0b958248068fb1703a30f99e419dc28861d78b004ad", kill_on_drop: false }`
[INFO] [stdout] 98f5a3804302b7125249e0b958248068fb1703a30f99e419dc28861d78b004ad
