[INFO] cloning repository https://github.com/sebm/checkers
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sebm/checkers" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebm%2Fcheckers", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebm%2Fcheckers'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 07cce72a883f38ab9297467b91354fdcaacf8298
[INFO] checking sebm/checkers against master#c919f490bbcd2b29b74016101f7ec71aaa24bdbb for pr-79073
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsebm%2Fcheckers" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sebm/checkers on toolchain c919f490bbcd2b29b74016101f7ec71aaa24bdbb
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c919f490bbcd2b29b74016101f7ec71aaa24bdbb" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sebm/checkers
[INFO] finished tweaking git repo https://github.com/sebm/checkers
[INFO] tweaked toml for git repo https://github.com/sebm/checkers written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/sebm/checkers already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+c919f490bbcd2b29b74016101f7ec71aaa24bdbb" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+c919f490bbcd2b29b74016101f7ec71aaa24bdbb" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e90707eefbaaa5c393bcc291fa2fb15065d96fa03923d4a9652be0a678c36bbd
[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" "e90707eefbaaa5c393bcc291fa2fb15065d96fa03923d4a9652be0a678c36bbd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e90707eefbaaa5c393bcc291fa2fb15065d96fa03923d4a9652be0a678c36bbd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e90707eefbaaa5c393bcc291fa2fb15065d96fa03923d4a9652be0a678c36bbd", kill_on_drop: false }`
[INFO] [stdout] e90707eefbaaa5c393bcc291fa2fb15065d96fa03923d4a9652be0a678c36bbd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+c919f490bbcd2b29b74016101f7ec71aaa24bdbb" "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] 88a12896346c32c5fe65b6006f586322f2348e31fad5955993de8bff4acf5f90
[INFO] running `Command { std: "docker" "start" "-a" "88a12896346c32c5fe65b6006f586322f2348e31fad5955993de8bff4acf5f90", kill_on_drop: false }`
[INFO] [stderr]     Checking checkers v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `initial_board`
[INFO] [stdout]  --> src/main.rs:4:26
[INFO] [stdout]   |
[INFO] [stdout] 4 | use board::{BoardSquare, initial_board, draw_board};
[INFO] [stdout]   |                          ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `initial_board`
[INFO] [stdout]  --> src/main.rs:4:26
[INFO] [stdout]   |
[INFO] [stdout] 4 | use board::{BoardSquare, initial_board, draw_board};
[INFO] [stdout]   |                          ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `initial_board`
[INFO] [stdout]   --> src/board.rs:26:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | pub fn initial_board() -> [[BoardSquare; 8]; 8] {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `initial_board`
[INFO] [stdout]   --> src/board.rs:26:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | pub fn initial_board() -> [[BoardSquare; 8]; 8] {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.73s
[INFO] running `Command { std: "docker" "inspect" "88a12896346c32c5fe65b6006f586322f2348e31fad5955993de8bff4acf5f90", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "88a12896346c32c5fe65b6006f586322f2348e31fad5955993de8bff4acf5f90", kill_on_drop: false }`
[INFO] [stdout] 88a12896346c32c5fe65b6006f586322f2348e31fad5955993de8bff4acf5f90