[INFO] fetching crate pebble 0.8.5...
[INFO] documenting pebble-0.8.5 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate pebble 0.8.5 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate pebble 0.8.5 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 pebble 0.8.5
[INFO] finished tweaking crates.io crate pebble 0.8.5
[INFO] tweaked toml for crates.io crate pebble 0.8.5 written to /workspace/builds/worker-4/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] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 6c2959f147b54740603a8b4f5dae9b3927841db8a015afafb55f7958efb99b3f
[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" "6c2959f147b54740603a8b4f5dae9b3927841db8a015afafb55f7958efb99b3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6c2959f147b54740603a8b4f5dae9b3927841db8a015afafb55f7958efb99b3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c2959f147b54740603a8b4f5dae9b3927841db8a015afafb55f7958efb99b3f", kill_on_drop: false }`
[INFO] [stdout] 6c2959f147b54740603a8b4f5dae9b3927841db8a015afafb55f7958efb99b3f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 318b8ce29f6ddbfa8087e4ae3a655fe4f1b796807097a9572259028561b9a96f
[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" "318b8ce29f6ddbfa8087e4ae3a655fe4f1b796807097a9572259028561b9a96f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking recipe-reader v0.9.11
[INFO] [stderr]     Checking lzf v0.3.1
[INFO] [stderr]  Documenting pebble v0.8.5 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(vec_remove_item)]
[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 `pebble`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type bin --crate-name pebble src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern ansi_term=/opt/rustwide/target/debug/deps/libansi_term-f020df4822bb9875.rmeta --extern lzf=/opt/rustwide/target/debug/deps/liblzf-f17a1193dd0faa95.rmeta --extern recipe_reader=/opt/rustwide/target/debug/deps/librecipe_reader-5628ab21107591ef.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-eb6cdf579abc545a.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-5f078a3096470b53.so --extern toml=/opt/rustwide/target/debug/deps/libtoml-cfd7d42b77a0a6c4.rmeta --cap-lints=warn --crate-version 0.8.5` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "318b8ce29f6ddbfa8087e4ae3a655fe4f1b796807097a9572259028561b9a96f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "318b8ce29f6ddbfa8087e4ae3a655fe4f1b796807097a9572259028561b9a96f", kill_on_drop: false }`
[INFO] [stdout] 318b8ce29f6ddbfa8087e4ae3a655fe4f1b796807097a9572259028561b9a96f
