[INFO] cloning repository https://github.com/adi-p/sudoku-solver
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/adi-p/sudoku-solver" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadi-p%2Fsudoku-solver", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadi-p%2Fsudoku-solver'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5f73248b95cb19579fe0053f6e865788ec012add
[INFO] checking adi-p/sudoku-solver against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fadi-p%2Fsudoku-solver" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/adi-p/sudoku-solver on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/adi-p/sudoku-solver
[INFO] finished tweaking git repo https://github.com/adi-p/sudoku-solver
[INFO] tweaked toml for git repo https://github.com/adi-p/sudoku-solver written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/adi-p/sudoku-solver already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b633fbdcd1d78acf74608144498bff4ce0760ed9118b1a5b887bf68a78b150a5
[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" "b633fbdcd1d78acf74608144498bff4ce0760ed9118b1a5b887bf68a78b150a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b633fbdcd1d78acf74608144498bff4ce0760ed9118b1a5b887bf68a78b150a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b633fbdcd1d78acf74608144498bff4ce0760ed9118b1a5b887bf68a78b150a5", kill_on_drop: false }`
[INFO] [stdout] b633fbdcd1d78acf74608144498bff4ce0760ed9118b1a5b887bf68a78b150a5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 37ca27076ed697ef878e25b9638b4131bd3dc5dab3422912bef5c6ad92091c0d
[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" "37ca27076ed697ef878e25b9638b4131bd3dc5dab3422912bef5c6ad92091c0d", kill_on_drop: false }`
[INFO] [stderr]     Checking sudoku-solver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct is never constructed: `Square`
[INFO] [stdout]  --> src/main.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct Square {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Constraint`
[INFO] [stdout]  --> src/main.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Constraint {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Square`
[INFO] [stdout]  --> src/main.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct Square {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Constraint`
[INFO] [stdout]  --> src/main.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Constraint {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.27s
[INFO] running `Command { std: "docker" "inspect" "37ca27076ed697ef878e25b9638b4131bd3dc5dab3422912bef5c6ad92091c0d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37ca27076ed697ef878e25b9638b4131bd3dc5dab3422912bef5c6ad92091c0d", kill_on_drop: false }`
[INFO] [stdout] 37ca27076ed697ef878e25b9638b4131bd3dc5dab3422912bef5c6ad92091c0d