[INFO] fetching crate hp-log 0.3.1...
[INFO] documenting hp-log-0.3.1 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate hp-log 0.3.1 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate hp-log 0.3.1 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 hp-log 0.3.1
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate hp-log 0.3.1
[INFO] tweaked toml for crates.io crate hp-log 0.3.1 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate crates.io crate hp-log 0.3.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "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-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] 78c885d03f340710e14061912d69e016e6f6af77f79c2a11043f075bd76d9502
[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" "78c885d03f340710e14061912d69e016e6f6af77f79c2a11043f075bd76d9502", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "78c885d03f340710e14061912d69e016e6f6af77f79c2a11043f075bd76d9502", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78c885d03f340710e14061912d69e016e6f6af77f79c2a11043f075bd76d9502", kill_on_drop: false }`
[INFO] [stdout] 78c885d03f340710e14061912d69e016e6f6af77f79c2a11043f075bd76d9502
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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] e650c440858f6dc50188cecf2421b21c5aa105fdc8c77392585a9f7ecf47bedb
[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" "e650c440858f6dc50188cecf2421b21c5aa105fdc8c77392585a9f7ecf47bedb", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.58
[INFO] [stderr]    Compiling syn v0.15.39
[INFO] [stderr]    Compiling serde v1.0.94
[INFO] [stderr]     Checking strfmt v0.1.6
[INFO] [stderr]     Checking log v0.4.6
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]     Checking time v0.1.42
[INFO] [stderr]    Compiling serde_derive v1.0.94
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]  Documenting hp-log v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:2
[INFO] [stdout]   |
[INFO] [stdout] 2 |  #![feature(rustc_private)]
[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 `hp-log`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name hp_log 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 lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-09be1e3f269d05b8.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-6a9f946ac7b23656.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-f2c3168e52cd61af.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-7d577c898540b653.so --extern strfmt=/opt/rustwide/target/debug/deps/libstrfmt-f02958c7c44e4088.rmeta --extern time=/opt/rustwide/target/debug/deps/libtime-46de7960c6a1a42f.rmeta --extern toml=/opt/rustwide/target/debug/deps/libtoml-1fb76bd77d6134a1.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "e650c440858f6dc50188cecf2421b21c5aa105fdc8c77392585a9f7ecf47bedb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e650c440858f6dc50188cecf2421b21c5aa105fdc8c77392585a9f7ecf47bedb", kill_on_drop: false }`
[INFO] [stdout] e650c440858f6dc50188cecf2421b21c5aa105fdc8c77392585a9f7ecf47bedb