[INFO] cloning repository https://github.com/sweepline/knights_tour
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sweepline/knights_tour" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweepline%2Fknights_tour", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweepline%2Fknights_tour'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4be8192e111ab2cd27ca12f45c5bba32e185b38d
[INFO] checking sweepline/knights_tour against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsweepline%2Fknights_tour" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sweepline/knights_tour on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sweepline/knights_tour
[INFO] finished tweaking git repo https://github.com/sweepline/knights_tour
[INFO] tweaked toml for git repo https://github.com/sweepline/knights_tour written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/sweepline/knights_tour already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "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-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 07ae02807fbf68ccf5de6e9213eb6c17b8b92dfecf2c549e8ace8086124df0c2
[INFO] running `Command { std: "docker" "start" "-a" "07ae02807fbf68ccf5de6e9213eb6c17b8b92dfecf2c549e8ace8086124df0c2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "07ae02807fbf68ccf5de6e9213eb6c17b8b92dfecf2c549e8ace8086124df0c2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "07ae02807fbf68ccf5de6e9213eb6c17b8b92dfecf2c549e8ace8086124df0c2", kill_on_drop: false }`
[INFO] [stdout] 07ae02807fbf68ccf5de6e9213eb6c17b8b92dfecf2c549e8ace8086124df0c2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b4f70a0277d185c06109faddd156e5755d9ac4b3ee7f9dc4f8395e6152018808
[INFO] running `Command { std: "docker" "start" "-a" "b4f70a0277d185c06109faddd156e5755d9ac4b3ee7f9dc4f8395e6152018808", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.15
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling libc v0.2.140
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling rayon-core v1.11.0
[INFO] [stderr]     Checking either v1.8.1
[INFO] [stderr]    Compiling memoffset v0.8.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.14
[INFO] [stderr]     Checking crossbeam-channel v0.5.7
[INFO] [stderr]     Checking num_cpus v1.15.0
[INFO] [stderr]     Checking crossbeam-deque v0.8.3
[INFO] [stderr]     Checking rayon v1.7.0
[INFO] [stderr]     Checking knights_tour v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `print_board` is never used
[INFO] [stdout]    --> src/main.rs:263:4
[INFO] [stdout]     |
[INFO] [stdout] 263 | fn print_board(pos: &u8, visited: &Visited) {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_board` is never used
[INFO] [stdout]    --> src/main.rs:263:4
[INFO] [stdout]     |
[INFO] [stdout] 263 | fn print_board(pos: &u8, visited: &Visited) {
[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] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.77s
[INFO] running `Command { std: "docker" "inspect" "b4f70a0277d185c06109faddd156e5755d9ac4b3ee7f9dc4f8395e6152018808", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b4f70a0277d185c06109faddd156e5755d9ac4b3ee7f9dc4f8395e6152018808", kill_on_drop: false }`
[INFO] [stdout] b4f70a0277d185c06109faddd156e5755d9ac4b3ee7f9dc4f8395e6152018808