[INFO] fetching crate zekin_data_structure 1.0.0...
[INFO] testing zekin_data_structure-1.0.0 against 1.60.0 for beta-1.61-1
[INFO] extracting crate zekin_data_structure 1.0.0 into /workspace/builds/worker-44/source
[INFO] validating manifest of crates.io crate zekin_data_structure 1.0.0 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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-44/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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-44/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-44/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 619d10cab159719e2210d7d9d677fbedee60be0ad5ea0b59086232c5ac5535b2
[INFO] running `Command { std: "docker" "start" "-a" "619d10cab159719e2210d7d9d677fbedee60be0ad5ea0b59086232c5ac5535b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "619d10cab159719e2210d7d9d677fbedee60be0ad5ea0b59086232c5ac5535b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "619d10cab159719e2210d7d9d677fbedee60be0ad5ea0b59086232c5ac5535b2", kill_on_drop: false }`
[INFO] [stdout] 619d10cab159719e2210d7d9d677fbedee60be0ad5ea0b59086232c5ac5535b2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-44/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-44/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" "RUSTFLAGS=--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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 777966e0fc87a6fd8c3fad8d479a9f796bf76103296875dfd5510b49a7ac39ec
[INFO] running `Command { std: "docker" "start" "-a" "777966e0fc87a6fd8c3fad8d479a9f796bf76103296875dfd5510b49a7ac39ec", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.80
[INFO] [stderr]    Compiling log v0.4.16
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]    Compiling bumpalo v3.9.1
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling serde_json v1.0.79
[INFO] [stderr]    Compiling ryu v1.0.9
[INFO] [stderr]    Compiling wasm-bindgen v0.2.80
[INFO] [stderr]    Compiling itoa v1.0.1
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling scoped-tls v1.0.0
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling wasm-bindgen-test-macro v0.3.30
[INFO] [stderr]    Compiling float-cmp v0.8.0
[INFO] [stderr]    Compiling wasm-bindgen-backend v0.2.80
[INFO] [stderr]    Compiling wasm-bindgen-macro-support v0.2.80
[INFO] [stderr]    Compiling getset v0.1.2
[INFO] [stderr]    Compiling wasm-bindgen-macro v0.2.80
[INFO] [stderr]    Compiling js-sys v0.3.57
[INFO] [stderr]    Compiling console_error_panic_hook v0.1.7
[INFO] [stderr]    Compiling wasm-bindgen-futures v0.4.30
[INFO] [stderr]    Compiling wasm-bindgen-test v0.3.30
[INFO] [stderr]    Compiling 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 compile `zekin_data_structure` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "777966e0fc87a6fd8c3fad8d479a9f796bf76103296875dfd5510b49a7ac39ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "777966e0fc87a6fd8c3fad8d479a9f796bf76103296875dfd5510b49a7ac39ec", kill_on_drop: false }`
[INFO] [stdout] 777966e0fc87a6fd8c3fad8d479a9f796bf76103296875dfd5510b49a7ac39ec