[INFO] fetching crate zekin_data_structure 1.0.0...
[INFO] documenting zekin_data_structure-1.0.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate zekin_data_structure 1.0.0 into /workspace/builds/worker-15/source
[INFO] validating manifest of crates.io crate zekin_data_structure 1.0.0 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate zekin_data_structure 1.0.0
[INFO] finished tweaking crates.io crate zekin_data_structure 1.0.0
[INFO] tweaked toml for crates.io crate zekin_data_structure 1.0.0 written to /workspace/builds/worker-15/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--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-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c9fe7b8971e34cd36f0652c8ebf36664de49c90179c21633e21b8cad32570426
[INFO] running `Command { std: "docker" "start" "-a" "c9fe7b8971e34cd36f0652c8ebf36664de49c90179c21633e21b8cad32570426", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c9fe7b8971e34cd36f0652c8ebf36664de49c90179c21633e21b8cad32570426", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9fe7b8971e34cd36f0652c8ebf36664de49c90179c21633e21b8cad32570426", kill_on_drop: false }`
[INFO] [stdout] c9fe7b8971e34cd36f0652c8ebf36664de49c90179c21633e21b8cad32570426
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-15/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 80e8eb5f4ca602960ae8fcbbaf984f989952bb300affb9b83193f5d9185be18a
[INFO] running `Command { std: "docker" "start" "-a" "80e8eb5f4ca602960ae8fcbbaf984f989952bb300affb9b83193f5d9185be18a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.80
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling bumpalo v3.9.1
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]     Checking itoa v1.0.2
[INFO] [stderr]    Compiling wasm-bindgen v0.2.80
[INFO] [stderr]     Checking ryu v1.0.10
[INFO] [stderr]     Checking scoped-tls v1.0.0
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]     Checking itertools v0.9.0
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling wasm-bindgen-test-macro v0.3.30
[INFO] [stderr]     Checking float-cmp v0.8.0
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.80
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.80
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.80
[INFO] [stderr]    Compiling getset v0.1.2
[INFO] [stderr]     Checking js-sys v0.3.57
[INFO] [stderr]     Checking console_error_panic_hook v0.1.7
[INFO] [stderr]     Checking wasm-bindgen-futures v0.4.30
[INFO] [stderr]     Checking wasm-bindgen-test v0.3.30
[INFO] [stderr]  Documenting zekin_data_structure v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:7:12
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(get_mut_unchecked)]
[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 document `zekin_data_structure`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type cdylib --crate-type rlib --crate-name zekin_data_structure src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=beb983ae222e8545 -L dependency=/opt/rustwide/target/debug/deps --extern float_cmp=/opt/rustwide/target/debug/deps/libfloat_cmp-e625786cb2b0e882.rmeta --extern getset=/opt/rustwide/target/debug/deps/libgetset-4b9d7471649c0d88.so --extern itertools=/opt/rustwide/target/debug/deps/libitertools-31732f101c7334d9.rmeta --extern js_sys=/opt/rustwide/target/debug/deps/libjs_sys-57550db2247f7884.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-17d88c7edd65f59e.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-5425aa8c5f005667.rmeta --extern wasm_bindgen=/opt/rustwide/target/debug/deps/libwasm_bindgen-fe12d4a862852fd8.rmeta --extern wasm_bindgen_test=/opt/rustwide/target/debug/deps/libwasm_bindgen_test-234ba70533c3f3f8.rmeta --cap-lints=warn --crate-version 1.0.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "80e8eb5f4ca602960ae8fcbbaf984f989952bb300affb9b83193f5d9185be18a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "80e8eb5f4ca602960ae8fcbbaf984f989952bb300affb9b83193f5d9185be18a", kill_on_drop: false }`
[INFO] [stdout] 80e8eb5f4ca602960ae8fcbbaf984f989952bb300affb9b83193f5d9185be18a