[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] checking scrogson/linked-list-rs against try#7c3a44cf5f95fa5cf164a312bdcf845157af7093 for pr-77325
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscrogson%2Flinked-list-rs" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scrogson/linked-list-rs on toolchain 7c3a44cf5f95fa5cf164a312bdcf845157af7093
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7c3a44cf5f95fa5cf164a312bdcf845157af7093" "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-8/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" "+7c3a44cf5f95fa5cf164a312bdcf845157af7093" "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-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+7c3a44cf5f95fa5cf164a312bdcf845157af7093" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8150fceab07f32c425666a171c0d92afca6130795daaf76beacad99d7c272edd
[INFO] running `Command { std: "docker" "start" "-a" "8150fceab07f32c425666a171c0d92afca6130795daaf76beacad99d7c272edd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8150fceab07f32c425666a171c0d92afca6130795daaf76beacad99d7c272edd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8150fceab07f32c425666a171c0d92afca6130795daaf76beacad99d7c272edd", kill_on_drop: false }`
[INFO] [stdout] 8150fceab07f32c425666a171c0d92afca6130795daaf76beacad99d7c272edd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+7c3a44cf5f95fa5cf164a312bdcf845157af7093" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 62e463353045f799c07baea3fd0af2a02175a85ee5fded482677a20e66bc0b09
[INFO] running `Command { std: "docker" "start" "-a" "62e463353045f799c07baea3fd0af2a02175a85ee5fded482677a20e66bc0b09", kill_on_drop: false }`
[INFO] [stderr]     Checking linked-list-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `tail`
[INFO] [stdout]  --> src/fourth.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     tail: Link<T>,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[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] 
[INFO] [stdout] warning: field is never read: `next`
[INFO] [stdout]   --> src/fourth.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     next: Link<T>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `prev`
[INFO] [stdout]   --> src/fourth.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     prev: Link<T>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `tail`
[INFO] [stdout]  --> src/fourth.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     tail: Link<T>,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[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] 
[INFO] [stdout] warning: field is never read: `next`
[INFO] [stdout]   --> src/fourth.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     next: Link<T>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `prev`
[INFO] [stdout]   --> src/fourth.rs:14:5
[INFO] [stdout]    |
[INFO] [stdout] 14 |     prev: Link<T>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.18s
[INFO] running `Command { std: "docker" "inspect" "62e463353045f799c07baea3fd0af2a02175a85ee5fded482677a20e66bc0b09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "62e463353045f799c07baea3fd0af2a02175a85ee5fded482677a20e66bc0b09", kill_on_drop: false }`
[INFO] [stdout] 62e463353045f799c07baea3fd0af2a02175a85ee5fded482677a20e66bc0b09