[INFO] cloning repository https://github.com/scrogson/linked-list-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/scrogson/linked-list-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscrogson%2Flinked-list-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscrogson%2Flinked-list-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f4a8134bc9afc1068719ca9e77705406fbb2f8fc
[INFO] testing scrogson/linked-list-rs against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscrogson%2Flinked-list-rs" "/workspace/builds/worker-77/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-77/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scrogson/linked-list-rs on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scrogson/linked-list-rs
[INFO] finished tweaking git repo https://github.com/scrogson/linked-list-rs
[INFO] tweaked toml for git repo https://github.com/scrogson/linked-list-rs written to /workspace/builds/worker-77/source/Cargo.toml
[INFO] crate git repo https://github.com/scrogson/linked-list-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--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-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e88b7053042920d9ece21d2257089c8e691a153f1b885b96b99c77c961bd4651
[INFO] running `Command { std: "docker" "start" "-a" "e88b7053042920d9ece21d2257089c8e691a153f1b885b96b99c77c961bd4651", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e88b7053042920d9ece21d2257089c8e691a153f1b885b96b99c77c961bd4651", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e88b7053042920d9ece21d2257089c8e691a153f1b885b96b99c77c961bd4651", kill_on_drop: false }`
[INFO] [stdout] e88b7053042920d9ece21d2257089c8e691a153f1b885b96b99c77c961bd4651
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 085562e45c63435dec0259a4fbbd392bcfa788a7e5f889302eced9310c6f9d1b
[INFO] running `Command { std: "docker" "start" "-a" "085562e45c63435dec0259a4fbbd392bcfa788a7e5f889302eced9310c6f9d1b", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling linked-list-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `elem`
[INFO] [stdout]   --> src/fourth.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     elem: T,
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.07s
[INFO] running `Command { std: "docker" "inspect" "085562e45c63435dec0259a4fbbd392bcfa788a7e5f889302eced9310c6f9d1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "085562e45c63435dec0259a4fbbd392bcfa788a7e5f889302eced9310c6f9d1b", kill_on_drop: false }`
[INFO] [stdout] 085562e45c63435dec0259a4fbbd392bcfa788a7e5f889302eced9310c6f9d1b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 16ce42b6f99d22a2906a7e358ba02a8e93c5a78c3518df0ebf79d23e2db2b701
[INFO] running `Command { std: "docker" "start" "-a" "16ce42b6f99d22a2906a7e358ba02a8e93c5a78c3518df0ebf79d23e2db2b701", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stdout] warning: field is never read: `elem`
[INFO] [stdout]   --> src/fourth.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     elem: T,
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling linked-list-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `elem`
[INFO] [stdout]   --> src/fourth.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     elem: T,
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `Command { std: "docker" "inspect" "16ce42b6f99d22a2906a7e358ba02a8e93c5a78c3518df0ebf79d23e2db2b701", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "16ce42b6f99d22a2906a7e358ba02a8e93c5a78c3518df0ebf79d23e2db2b701", kill_on_drop: false }`
[INFO] [stdout] 16ce42b6f99d22a2906a7e358ba02a8e93c5a78c3518df0ebf79d23e2db2b701
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-77/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] c8ec50bb2ebdd8d366e9e81d8ff0a58ffd1c2626351c7f84a75d5d45becbc221
[INFO] running `Command { std: "docker" "start" "-a" "c8ec50bb2ebdd8d366e9e81d8ff0a58ffd1c2626351c7f84a75d5d45becbc221", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: field is never read: `elem`
[INFO] [stderr]   --> src/fourth.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     elem: T,
[INFO] [stderr]    |     ^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `linked-list-rs` (lib) generated 1 warning
[INFO] [stderr] warning: `linked-list-rs` (lib test) generated 1 warning (1 duplicate)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 3.15s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/linked_list_rs-7e8fb85b41fdf6a8)
[INFO] [stdout] 
[INFO] [stdout] running 8 tests
[INFO] [stdout] test second::tests::basics ... ok
[INFO] [stdout] test second::tests::peek ... ok
[INFO] [stdout] test second::tests::into_iter ... ok
[INFO] [stdout] test first::tests::basics ... ok
[INFO] [stdout] test second::tests::iter_mut ... ok
[INFO] [stdout] test third::tests::iter ... ok
[INFO] [stdout] test third::tests::basics ... ok
[INFO] [stdout] test second::tests::iter ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 8 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.02s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests linked-list-rs
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "c8ec50bb2ebdd8d366e9e81d8ff0a58ffd1c2626351c7f84a75d5d45becbc221", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c8ec50bb2ebdd8d366e9e81d8ff0a58ffd1c2626351c7f84a75d5d45becbc221", kill_on_drop: false }`
[INFO] [stdout] c8ec50bb2ebdd8d366e9e81d8ff0a58ffd1c2626351c7f84a75d5d45becbc221