[INFO] cloning repository https://github.com/SpaceEraser/wordscapes_helper
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/SpaceEraser/wordscapes_helper" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpaceEraser%2Fwordscapes_helper", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpaceEraser%2Fwordscapes_helper'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] aa8b2695387692029f97d1445531d0b23cdcc35c
[INFO] documenting SpaceEraser/wordscapes_helper against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSpaceEraser%2Fwordscapes_helper" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/SpaceEraser/wordscapes_helper 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 git repo https://github.com/SpaceEraser/wordscapes_helper
[INFO] finished tweaking git repo https://github.com/SpaceEraser/wordscapes_helper
[INFO] tweaked toml for git repo https://github.com/SpaceEraser/wordscapes_helper written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/SpaceEraser/wordscapes_helper 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] c8f71cfe679e8721e24999972d95d70531884f226fd20217cb9d8d5855c44168
[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" "c8f71cfe679e8721e24999972d95d70531884f226fd20217cb9d8d5855c44168", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c8f71cfe679e8721e24999972d95d70531884f226fd20217cb9d8d5855c44168", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c8f71cfe679e8721e24999972d95d70531884f226fd20217cb9d8d5855c44168", kill_on_drop: false }`
[INFO] [stdout] c8f71cfe679e8721e24999972d95d70531884f226fd20217cb9d8d5855c44168
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5bc2c8cfe8134a45cda2fbd3d01bab6953453d439a75f47eba2bf31d6ecc885a
[INFO] running `Command { std: "docker" "start" "-a" "5bc2c8cfe8134a45cda2fbd3d01bab6953453d439a75f47eba2bf31d6ecc885a", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.36
[INFO] [stderr]     Checking fixedbitset v0.3.0
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]     Checking ndarray v0.13.1
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.67
[INFO] [stderr]    Compiling serde_derive v1.0.114
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.67
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.67
[INFO] [stderr]     Checking wasm-bindgen v0.2.67
[INFO] [stderr]     Checking console_error_panic_hook v0.1.6
[INFO] [stderr]     Checking serde v1.0.114
[INFO] [stderr]     Checking petgraph v0.5.1
[INFO] [stderr]     Checking bincode v1.3.1
[INFO] [stderr]     Checking wordscapes-helper v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]  Documenting wordscapes-helper v0.1.0 (/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(iterator_fold_self)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(move_ref_pattern)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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(iterator_fold_self)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(move_ref_pattern)]
[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] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `wordscapes-helper`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type cdylib --crate-type rlib --crate-name wordscapes_helper 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 bincode=/opt/rustwide/target/debug/deps/libbincode-60335869c9566abc.rmeta --extern console_error_panic_hook=/opt/rustwide/target/debug/deps/libconsole_error_panic_hook-2626fc9434ca0ce8.rmeta --extern fixedbitset=/opt/rustwide/target/debug/deps/libfixedbitset-c11f736149e00168.rmeta --extern ndarray=/opt/rustwide/target/debug/deps/libndarray-d9b97e39c2357e63.rmeta --extern petgraph=/opt/rustwide/target/debug/deps/libpetgraph-a06df1dc12ae124b.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-d3b28729235cbbaf.rmeta --extern wasm_bindgen=/opt/rustwide/target/debug/deps/libwasm_bindgen-e562b81103c07a65.rmeta --cap-lints=warn` (exit code: 1)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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: build failed
[INFO] running `Command { std: "docker" "inspect" "5bc2c8cfe8134a45cda2fbd3d01bab6953453d439a75f47eba2bf31d6ecc885a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5bc2c8cfe8134a45cda2fbd3d01bab6953453d439a75f47eba2bf31d6ecc885a", kill_on_drop: false }`
[INFO] [stdout] 5bc2c8cfe8134a45cda2fbd3d01bab6953453d439a75f47eba2bf31d6ecc885a