[INFO] fetching crate abci2 0.1.2...
[INFO] documenting abci2-0.1.2 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate abci2 0.1.2 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate abci2 0.1.2 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 abci2 0.1.2
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate abci2 0.1.2
[INFO] tweaked toml for crates.io crate abci2 0.1.2 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate crates.io crate abci2 0.1.2 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-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] c520ef48249db8c6dbdd841b07b1b6f43b011c10cb7fa3a9e478710786a11048
[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" "c520ef48249db8c6dbdd841b07b1b6f43b011c10cb7fa3a9e478710786a11048", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c520ef48249db8c6dbdd841b07b1b6f43b011c10cb7fa3a9e478710786a11048", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c520ef48249db8c6dbdd841b07b1b6f43b011c10cb7fa3a9e478710786a11048", kill_on_drop: false }`
[INFO] [stdout] c520ef48249db8c6dbdd841b07b1b6f43b011c10cb7fa3a9e478710786a11048
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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] 90c726e60d0399126a54fa9038d3f230c41b19dd9a7078c799a0d98cfd9190b3
[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" "90c726e60d0399126a54fa9038d3f230c41b19dd9a7078c799a0d98cfd9190b3", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling protobuf v2.10.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]     Checking backtrace v0.3.41
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]     Checking failure v0.1.6
[INFO] [stderr]  Documenting abci2 v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(trait_alias)]
[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 `abci2`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name abci2 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 failure=/opt/rustwide/target/debug/deps/libfailure-a9608394d6a637d3.rmeta --extern protobuf=/opt/rustwide/target/debug/deps/libprotobuf-e4f31d10944fd90a.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "90c726e60d0399126a54fa9038d3f230c41b19dd9a7078c799a0d98cfd9190b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "90c726e60d0399126a54fa9038d3f230c41b19dd9a7078c799a0d98cfd9190b3", kill_on_drop: false }`
[INFO] [stdout] 90c726e60d0399126a54fa9038d3f230c41b19dd9a7078c799a0d98cfd9190b3