[INFO] fetching crate immutable 0.1.1...
[INFO] checking immutable-0.1.1 against master#4fa76a4a7742bb9c1febe33019f5a9e7e4839a65 for pr-83744
[INFO] extracting crate immutable 0.1.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate immutable 0.1.1 on toolchain 4fa76a4a7742bb9c1febe33019f5a9e7e4839a65
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate immutable 0.1.1
[INFO] finished tweaking crates.io crate immutable 0.1.1
[INFO] tweaked toml for crates.io crate immutable 0.1.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e2eef7c961515f4f968ffe0630f7b77d085ca17981b6232a587af4e59e6f80af
[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" "e2eef7c961515f4f968ffe0630f7b77d085ca17981b6232a587af4e59e6f80af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e2eef7c961515f4f968ffe0630f7b77d085ca17981b6232a587af4e59e6f80af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2eef7c961515f4f968ffe0630f7b77d085ca17981b6232a587af4e59e6f80af", kill_on_drop: false }`
[INFO] [stdout] e2eef7c961515f4f968ffe0630f7b77d085ca17981b6232a587af4e59e6f80af
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=forbid" "-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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "check" "--frozen" "--all" "--all-targets" "--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] 4b2bee09361e421fd08691c90b7d9971086a1f4ab722702f798c80f7dbeee913
[INFO] running `Command { std: "docker" "start" "-a" "4b2bee09361e421fd08691c90b7d9971086a1f4ab722702f798c80f7dbeee913", kill_on_drop: false }`
[INFO] [stderr]     Checking immutable v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::vec::IntoIter`
[INFO] [stdout]  --> src/list.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::vec::IntoIter;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::vec::IntoIter`
[INFO] [stdout]  --> src/list.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::vec::IntoIter;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused attribute
[INFO] [stdout]  --> src/list.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #[macro_escape]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_attributes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused attribute
[INFO] [stdout]   --> src/tree/binary_tree.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #[macro_escape]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused attribute
[INFO] [stdout]  --> src/list.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #[macro_escape]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_attributes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused attribute
[INFO] [stdout]   --> src/tree/binary_tree.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #[macro_escape]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.56s
[INFO] running `Command { std: "docker" "inspect" "4b2bee09361e421fd08691c90b7d9971086a1f4ab722702f798c80f7dbeee913", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b2bee09361e421fd08691c90b7d9971086a1f4ab722702f798c80f7dbeee913", kill_on_drop: false }`
[INFO] [stdout] 4b2bee09361e421fd08691c90b7d9971086a1f4ab722702f798c80f7dbeee913