[INFO] cloning repository https://github.com/twitchax/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/twitchax/sudoku_solver" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftwitchax%2Fsudoku_solver", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftwitchax%2Fsudoku_solver'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dde99062fe11ecedc05036db3ef7b0ea0cef930c
[INFO] testing twitchax/sudoku_solver against 1.60.0 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftwitchax%2Fsudoku_solver" "/workspace/builds/worker-43/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-43/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/twitchax/sudoku_solver on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/twitchax/sudoku_solver
[INFO] finished tweaking git repo https://github.com/twitchax/sudoku_solver
[INFO] tweaked toml for git repo https://github.com/twitchax/sudoku_solver written to /workspace/builds/worker-43/source/Cargo.toml
[INFO] crate git repo https://github.com/twitchax/sudoku_solver already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded simple_logger v1.6.0
[INFO] [stderr]   Downloaded core_affinity v0.5.10
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-43/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-43/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3f7640e605295e6743a6a07d2fe3d1f353dcea73fe849bb071484c57799d99cd
[INFO] running `Command { std: "docker" "start" "-a" "3f7640e605295e6743a6a07d2fe3d1f353dcea73fe849bb071484c57799d99cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3f7640e605295e6743a6a07d2fe3d1f353dcea73fe849bb071484c57799d99cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3f7640e605295e6743a6a07d2fe3d1f353dcea73fe849bb071484c57799d99cd", kill_on_drop: false }`
[INFO] [stdout] 3f7640e605295e6743a6a07d2fe3d1f353dcea73fe849bb071484c57799d99cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-43/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-43/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a84cadb2686d73ac01c341a138148b11a522feb14bb5d9f4c24b438bff25774b
[INFO] running `Command { std: "docker" "start" "-a" "a84cadb2686d73ac01c341a138148b11a522feb14bb5d9f4c24b438bff25774b", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling libc v0.2.72
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling once_cell v1.4.1
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling time v0.1.43
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling colored v1.9.3
[INFO] [stderr]    Compiling core_affinity v0.5.10
[INFO] [stderr]    Compiling chrono v0.4.13
[INFO] [stderr]    Compiling crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling crossbeam-channel v0.4.2
[INFO] [stderr]    Compiling crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling simple_logger v1.6.0
[INFO] [stderr]    Compiling crossbeam v0.7.3
[INFO] [stderr]    Compiling sudoku_solver v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `num_workers`
[INFO] [stdout]   --> src/beggar_pool.rs:28:5
[INFO] [stdout]    |
[INFO] [stdout] 28 |     num_workers: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] note: `BeggarPool` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   --> src/beggar_pool.rs:23:10
[INFO] [stdout]    |
[INFO] [stdout] 23 | #[derive(Clone)]
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout]    = note: this warning originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(test)]
[INFO] [stdout]   |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `sudoku_solver` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "a84cadb2686d73ac01c341a138148b11a522feb14bb5d9f4c24b438bff25774b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a84cadb2686d73ac01c341a138148b11a522feb14bb5d9f4c24b438bff25774b", kill_on_drop: false }`
[INFO] [stdout] a84cadb2686d73ac01c341a138148b11a522feb14bb5d9f4c24b438bff25774b