[INFO] fetching crate maybe_utf8 0.2.3...
[INFO] documenting maybe_utf8-0.2.3 against beta-2020-10-09 for beta-1.48-rustdoc-1
[INFO] extracting crate maybe_utf8 0.2.3 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate maybe_utf8 0.2.3 on toolchain beta-2020-10-09
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate maybe_utf8 0.2.3
[INFO] finished tweaking crates.io crate maybe_utf8 0.2.3
[INFO] tweaked toml for crates.io crate maybe_utf8 0.2.3 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "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" "+beta-2020-10-09" "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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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-2020-10-09" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 57883bddc04b1d0c2be20cebad801772e726e16b978acc52b1c580bae51b710b
[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" "57883bddc04b1d0c2be20cebad801772e726e16b978acc52b1c580bae51b710b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "57883bddc04b1d0c2be20cebad801772e726e16b978acc52b1c580bae51b710b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "57883bddc04b1d0c2be20cebad801772e726e16b978acc52b1c580bae51b710b", kill_on_drop: false }`
[INFO] [stdout] 57883bddc04b1d0c2be20cebad801772e726e16b978acc52b1c580bae51b710b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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-2020-10-09" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0fe913ab9f519c9ff0caa183225d9468f02cd540bb80d15a4e6c8d9e251fd0de
[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" "0fe913ab9f519c9ff0caa183225d9468f02cd540bb80d15a4e6c8d9e251fd0de", kill_on_drop: false }`
[INFO] [stderr]  Documenting maybe_utf8 v0.2.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `std::borrow::IntoCow`
[INFO] [stdout]   --> lib.rs:66:19
[INFO] [stdout]    |
[INFO] [stdout] 66 | use std::borrow::{IntoCow, Cow, ToOwned};
[INFO] [stdout]    |                   ^^^^^^^ no `IntoCow` in `borrow`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> lib.rs:63:1
[INFO] [stdout]    |
[INFO] [stdout] 63 | #![feature(core)]
[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] Some errors have detailed explanations: E0432, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `maybe_utf8`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name maybe_utf8 lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --cap-lints=warn --crate-version 0.2.3` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "0fe913ab9f519c9ff0caa183225d9468f02cd540bb80d15a4e6c8d9e251fd0de", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0fe913ab9f519c9ff0caa183225d9468f02cd540bb80d15a4e6c8d9e251fd0de", kill_on_drop: false }`
[INFO] [stdout] 0fe913ab9f519c9ff0caa183225d9468f02cd540bb80d15a4e6c8d9e251fd0de
