[INFO] fetching crate automatic-relations 0.2.1...
[INFO] documenting automatic-relations-0.2.1 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate automatic-relations 0.2.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate automatic-relations 0.2.1 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 automatic-relations 0.2.1
[INFO] finished tweaking crates.io crate automatic-relations 0.2.1
[INFO] tweaked toml for crates.io crate automatic-relations 0.2.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate automatic-relations 0.2.1 already has a lockfile, it will not be regenerated
[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-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] 9f536ce9fb9d7ea2c5ddd0fdf3ed422a601a459a9a9d282ec884a7361386e2f5
[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" "9f536ce9fb9d7ea2c5ddd0fdf3ed422a601a459a9a9d282ec884a7361386e2f5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9f536ce9fb9d7ea2c5ddd0fdf3ed422a601a459a9a9d282ec884a7361386e2f5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f536ce9fb9d7ea2c5ddd0fdf3ed422a601a459a9a9d282ec884a7361386e2f5", kill_on_drop: false }`
[INFO] [stdout] 9f536ce9fb9d7ea2c5ddd0fdf3ed422a601a459a9a9d282ec884a7361386e2f5
[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] f7397d76fdc824c640eec09a09c1fe6228045f77af5431f1826fd7fb83360faa
[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" "f7397d76fdc824c640eec09a09c1fe6228045f77af5431f1826fd7fb83360faa", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.76
[INFO] [stderr]     Checking immutable-map v0.1.2
[INFO] [stderr]     Checking union-find v0.3.2
[INFO] [stderr]     Checking once_cell v1.4.1
[INFO] [stderr]     Checking crossbeam-utils v0.7.2
[INFO] [stderr]     Checking crossbeam-channel v0.4.3
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking terms v0.1.3
[INFO] [stderr]     Checking tree-automata v0.1.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/tree-automata-0.1.2/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(trait_alias)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tree-automata`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "f7397d76fdc824c640eec09a09c1fe6228045f77af5431f1826fd7fb83360faa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7397d76fdc824c640eec09a09c1fe6228045f77af5431f1826fd7fb83360faa", kill_on_drop: false }`
[INFO] [stdout] f7397d76fdc824c640eec09a09c1fe6228045f77af5431f1826fd7fb83360faa
