[INFO] cloning repository https://github.com/joshuacox1/exact-cover
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/joshuacox1/exact-cover" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoshuacox1%2Fexact-cover", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoshuacox1%2Fexact-cover'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0f435891e004c4cf6aba04ac7353e45601b68545
[INFO] testing joshuacox1/exact-cover against beta-2025-09-21 for beta-1.91-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoshuacox1%2Fexact-cover" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/joshuacox1/exact-cover
[INFO] finished tweaking git repo https://github.com/joshuacox1/exact-cover
[INFO] tweaked toml for git repo https://github.com/joshuacox1/exact-cover written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/joshuacox1/exact-cover on toolchain beta-2025-09-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/joshuacox1/exact-cover 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" "+beta-2025-09-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6bd047ba9991777a40c8a16d2bafc8a78578d58186ecfce480b80035eb49542a
[INFO] running `Command { std: "docker" "start" "-a" "6bd047ba9991777a40c8a16d2bafc8a78578d58186ecfce480b80035eb49542a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6bd047ba9991777a40c8a16d2bafc8a78578d58186ecfce480b80035eb49542a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6bd047ba9991777a40c8a16d2bafc8a78578d58186ecfce480b80035eb49542a", kill_on_drop: false }`
[INFO] [stdout] 6bd047ba9991777a40c8a16d2bafc8a78578d58186ecfce480b80035eb49542a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a9708aa94304277189e5781bdcac70267860bfa17c1f63cfac92172ea0266e77
[INFO] running `Command { std: "docker" "start" "-a" "a9708aa94304277189e5781bdcac70267860bfa17c1f63cfac92172ea0266e77", kill_on_drop: false }`
[INFO] [stderr]    Compiling either v1.15.0
[INFO] [stderr]    Compiling bumpalo v3.19.0
[INFO] [stderr]    Compiling arrayvec v0.7.6
[INFO] [stderr]    Compiling itertools v0.14.0
[INFO] [stderr]    Compiling exact_cover_solver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `ExactCoverSolver`
[INFO] [stdout]  --> src/solver/representable.rs:2:17
[INFO] [stdout]   |
[INFO] [stdout] 2 |     ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `arrayvec::ArrayVec`
[INFO] [stdout]  --> src/solver/solver.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use arrayvec::ArrayVec;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/solver/solver.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `ENTRY_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to upper camel case: `EntryIdx`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `COL_OR_ROW_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^ help: convert the identifier to upper camel case: `ColOrRowIdx`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `ExactCoverProblemError` and `SparseBinaryMatrix`
[INFO] [stdout]   --> src/solver/mod.rs:12:38
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub use problem::{ExactCoverProblem, ExactCoverProblemError,
[INFO] [stdout]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 13 | SparseBinaryMatrix};
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ExactCoverSolver`
[INFO] [stdout]  --> src/problems/n_queens.rs:7:21
[INFO] [stdout]   |
[INFO] [stdout] 7 |         ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover,
[INFO] [stdout]   |                     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `o_rows` and `empty_rows` are never read
[INFO] [stdout]   --> src/solver/solver.rs:59:5
[INFO] [stdout]    |
[INFO] [stdout] 54 | pub struct ExactCoverSolver {
[INFO] [stdout]    |            ---------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 59 |     o_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 64 |     empty_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ExactCoverSolver` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_COLS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:73:7
[INFO] [stdout]    |
[INFO] [stdout] 73 | const MAX_COLS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ROWS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:74:7
[INFO] [stdout]    |
[INFO] [stdout] 74 | const MAX_ROWS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ONES` is never used
[INFO] [stdout]   --> src/solver/solver.rs:75:7
[INFO] [stdout]    |
[INFO] [stdout] 75 | const MAX_ONES: usize = 65536 - MAX_COLS;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `ENTRY_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `COL_OR_ROW_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:346:27
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions {
[INFO] [stdout]     |                           ^^^^^^^^^     ^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions<'_> {
[INFO] [stdout]     |                                                  ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:351:23
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps {
[INFO] [stdout]     |                       ^^^^^^^^^     ^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                       |
[INFO] [stdout]     |                       the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps<'_> {
[INFO] [stdout]     |                                                ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Duration` and `Instant`
[INFO] [stdout]  --> src/main.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::time::{Duration, Instant};
[INFO] [stdout]   |                 ^^^^^^^^  ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `bumpalo::Bump`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use bumpalo::Bump;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::sleep`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::thread::sleep;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `SolverStep`
[INFO] [stdout]  --> src/main.rs:8:48
[INFO] [stdout]   |
[INFO] [stdout] 8 |     ExactCoverSolver, ExactCoverRepresentable, SolverStep
[INFO] [stdout]   |                                                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.22s
[INFO] running `Command { std: "docker" "inspect" "a9708aa94304277189e5781bdcac70267860bfa17c1f63cfac92172ea0266e77", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a9708aa94304277189e5781bdcac70267860bfa17c1f63cfac92172ea0266e77", kill_on_drop: false }`
[INFO] [stdout] a9708aa94304277189e5781bdcac70267860bfa17c1f63cfac92172ea0266e77
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 12753b0f90dddadbd09dd85e8d1a082e4c4def538254b4c91fc0a11d001be348
[INFO] running `Command { std: "docker" "start" "-a" "12753b0f90dddadbd09dd85e8d1a082e4c4def538254b4c91fc0a11d001be348", kill_on_drop: false }`
[INFO] [stdout] warning: unused import: `ExactCoverSolver`
[INFO] [stdout]  --> src/solver/representable.rs:2:17
[INFO] [stdout]   |
[INFO] [stdout] 2 |     ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `arrayvec::ArrayVec`
[INFO] [stdout]  --> src/solver/solver.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use arrayvec::ArrayVec;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/solver/solver.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `ENTRY_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to upper camel case: `EntryIdx`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `COL_OR_ROW_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^ help: convert the identifier to upper camel case: `ColOrRowIdx`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `ExactCoverProblemError` and `SparseBinaryMatrix`
[INFO] [stdout]   --> src/solver/mod.rs:12:38
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub use problem::{ExactCoverProblem, ExactCoverProblemError,
[INFO] [stdout]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 13 | SparseBinaryMatrix};
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ExactCoverSolver`
[INFO] [stdout]  --> src/problems/n_queens.rs:7:21
[INFO] [stdout]   |
[INFO] [stdout] 7 |         ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover,
[INFO] [stdout]   |                     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling exact_cover_solver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: fields `o_rows` and `empty_rows` are never read
[INFO] [stdout]   --> src/solver/solver.rs:59:5
[INFO] [stdout]    |
[INFO] [stdout] 54 | pub struct ExactCoverSolver {
[INFO] [stdout]    |            ---------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 59 |     o_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 64 |     empty_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ExactCoverSolver` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_COLS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:73:7
[INFO] [stdout]    |
[INFO] [stdout] 73 | const MAX_COLS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ROWS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:74:7
[INFO] [stdout]    |
[INFO] [stdout] 74 | const MAX_ROWS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ONES` is never used
[INFO] [stdout]   --> src/solver/solver.rs:75:7
[INFO] [stdout]    |
[INFO] [stdout] 75 | const MAX_ONES: usize = 65536 - MAX_COLS;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `ENTRY_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `COL_OR_ROW_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:346:27
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions {
[INFO] [stdout]     |                           ^^^^^^^^^     ^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions<'_> {
[INFO] [stdout]     |                                                  ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:351:23
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps {
[INFO] [stdout]     |                       ^^^^^^^^^     ^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                       |
[INFO] [stdout]     |                       the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps<'_> {
[INFO] [stdout]     |                                                ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Duration` and `Instant`
[INFO] [stdout]  --> src/main.rs:1:17
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::time::{Duration, Instant};
[INFO] [stdout]   |                 ^^^^^^^^  ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `bumpalo::Bump`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use bumpalo::Bump;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::thread::sleep`
[INFO] [stdout]  --> src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::thread::sleep;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `SolverStep`
[INFO] [stdout]  --> src/main.rs:8:48
[INFO] [stdout]   |
[INFO] [stdout] 8 |     ExactCoverSolver, ExactCoverRepresentable, SolverStep
[INFO] [stdout]   |                                                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ExactCoverSolver`
[INFO] [stdout]  --> src/solver/representable.rs:2:17
[INFO] [stdout]   |
[INFO] [stdout] 2 |     ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `arrayvec::ArrayVec`
[INFO] [stdout]  --> src/solver/solver.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use arrayvec::ArrayVec;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `itertools::Itertools`
[INFO] [stdout]  --> src/solver/solver.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use itertools::Itertools;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `ENTRY_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to upper camel case: `EntryIdx`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `COL_OR_ROW_IDX` should have an upper camel case name
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^ help: convert the identifier to upper camel case: `ColOrRowIdx`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `ExactCoverRepresentable` and `problems::NQueens`
[INFO] [stdout]  --> src/solver/tests/cases.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     problems::NQueens,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 8 |     solver::{ExactCover, ExactCoverSolver, ExactCoverRepresentable,
[INFO] [stdout]   |                                            ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ExactCoverProblemError`
[INFO] [stdout]   --> src/solver/mod.rs:12:38
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub use problem::{ExactCoverProblem, ExactCoverProblemError,
[INFO] [stdout]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `o_rows` and `empty_rows` are never read
[INFO] [stdout]   --> src/solver/solver.rs:59:5
[INFO] [stdout]    |
[INFO] [stdout] 54 | pub struct ExactCoverSolver {
[INFO] [stdout]    |            ---------------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 59 |     o_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 64 |     empty_rows: Vec<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ExactCoverSolver` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_COLS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:73:7
[INFO] [stdout]    |
[INFO] [stdout] 73 | const MAX_COLS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ROWS` is never used
[INFO] [stdout]   --> src/solver/solver.rs:74:7
[INFO] [stdout]    |
[INFO] [stdout] 74 | const MAX_ROWS: usize = 4096;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant `MAX_ONES` is never used
[INFO] [stdout]   --> src/solver/solver.rs:75:7
[INFO] [stdout]    |
[INFO] [stdout] 75 | const MAX_ONES: usize = 65536 - MAX_COLS;
[INFO] [stdout]    |       ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `ENTRY_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:83:6
[INFO] [stdout]    |
[INFO] [stdout] 83 | type ENTRY_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `COL_OR_ROW_IDX` is never used
[INFO] [stdout]   --> src/solver/solver.rs:84:6
[INFO] [stdout]    |
[INFO] [stdout] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stdout]    |      ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:346:27
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions {
[INFO] [stdout]     |                           ^^^^^^^^^     ^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                           |
[INFO] [stdout]     |                           the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 346 |     pub fn iter_solutions(&mut self) -> Solutions<'_> {
[INFO] [stdout]     |                                                  ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/solver/solver.rs:351:23
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps {
[INFO] [stdout]     |                       ^^^^^^^^^     ^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                       |
[INFO] [stdout]     |                       the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 351 |     pub fn iter_steps(&mut self) -> SolverSteps<'_> {
[INFO] [stdout]     |                                                ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 1.24s
[INFO] running `Command { std: "docker" "inspect" "12753b0f90dddadbd09dd85e8d1a082e4c4def538254b4c91fc0a11d001be348", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "12753b0f90dddadbd09dd85e8d1a082e4c4def538254b4c91fc0a11d001be348", kill_on_drop: false }`
[INFO] [stdout] 12753b0f90dddadbd09dd85e8d1a082e4c4def538254b4c91fc0a11d001be348
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] ce02119dd4e80cc2dc0c908ceab5b870ac87d1278fd81e3855a0f42683b55a55
[INFO] running `Command { std: "docker" "start" "-a" "ce02119dd4e80cc2dc0c908ceab5b870ac87d1278fd81e3855a0f42683b55a55", kill_on_drop: false }`
[INFO] [stderr] warning: unused import: `ExactCoverSolver`
[INFO] [stderr]  --> src/solver/representable.rs:2:17
[INFO] [stderr]   |
[INFO] [stderr] 2 |     ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover
[INFO] [stderr]   |                 ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `arrayvec::ArrayVec`
[INFO] [stderr]  --> src/solver/solver.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use arrayvec::ArrayVec;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `itertools::Itertools`
[INFO] [stderr]  --> src/solver/solver.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use itertools::Itertools;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: type `ENTRY_IDX` should have an upper camel case name
[INFO] [stderr]   --> src/solver/solver.rs:83:6
[INFO] [stderr]    |
[INFO] [stderr] 83 | type ENTRY_IDX = u16;
[INFO] [stderr]    |      ^^^^^^^^^ help: convert the identifier to upper camel case: `EntryIdx`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(non_camel_case_types)]` (part of `#[warn(nonstandard_style)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: type `COL_OR_ROW_IDX` should have an upper camel case name
[INFO] [stderr]   --> src/solver/solver.rs:84:6
[INFO] [stderr]    |
[INFO] [stderr] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stderr]    |      ^^^^^^^^^^^^^^ help: convert the identifier to upper camel case: `ColOrRowIdx`
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `ExactCoverProblemError` and `SparseBinaryMatrix`
[INFO] [stderr]   --> src/solver/mod.rs:12:38
[INFO] [stderr]    |
[INFO] [stderr] 12 | pub use problem::{ExactCoverProblem, ExactCoverProblemError,
[INFO] [stderr]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 13 | SparseBinaryMatrix};
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `ExactCoverSolver`
[INFO] [stderr]  --> src/problems/n_queens.rs:7:21
[INFO] [stderr]   |
[INFO] [stderr] 7 |         ExactCover, ExactCoverSolver, ExactCoverProblem, PartialCover,
[INFO] [stderr]   |                     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: fields `o_rows` and `empty_rows` are never read
[INFO] [stderr]   --> src/solver/solver.rs:59:5
[INFO] [stderr]    |
[INFO] [stderr] 54 | pub struct ExactCoverSolver {
[INFO] [stderr]    |            ---------------- fields in this struct
[INFO] [stderr] ...
[INFO] [stderr] 59 |     o_rows: Vec<usize>,
[INFO] [stderr]    |     ^^^^^^
[INFO] [stderr] ...
[INFO] [stderr] 64 |     empty_rows: Vec<usize>,
[INFO] [stderr]    |     ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `ExactCoverSolver` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stderr]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant `MAX_COLS` is never used
[INFO] [stderr]   --> src/solver/solver.rs:73:7
[INFO] [stderr]    |
[INFO] [stderr] 73 | const MAX_COLS: usize = 4096;
[INFO] [stderr]    |       ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant `MAX_ROWS` is never used
[INFO] [stderr]   --> src/solver/solver.rs:74:7
[INFO] [stderr]    |
[INFO] [stderr] 74 | const MAX_ROWS: usize = 4096;
[INFO] [stderr]    |       ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant `MAX_ONES` is never used
[INFO] [stderr]   --> src/solver/solver.rs:75:7
[INFO] [stderr]    |
[INFO] [stderr] 75 | const MAX_ONES: usize = 65536 - MAX_COLS;
[INFO] [stderr]    |       ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: type alias `ENTRY_IDX` is never used
[INFO] [stderr]   --> src/solver/solver.rs:83:6
[INFO] [stderr]    |
[INFO] [stderr] 83 | type ENTRY_IDX = u16;
[INFO] [stderr]    |      ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: type alias `COL_OR_ROW_IDX` is never used
[INFO] [stderr]   --> src/solver/solver.rs:84:6
[INFO] [stderr]    |
[INFO] [stderr] 84 | type COL_OR_ROW_IDX = u16;
[INFO] [stderr]    |      ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stderr]    --> src/solver/solver.rs:346:27
[INFO] [stderr]     |
[INFO] [stderr] 346 |     pub fn iter_solutions(&mut self) -> Solutions {
[INFO] [stderr]     |                           ^^^^^^^^^     ^^^^^^^^^ the same lifetime is hidden here
[INFO] [stderr]     |                           |
[INFO] [stderr]     |                           the lifetime is elided here
[INFO] [stderr]     |
[INFO] [stderr]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stderr]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stderr] help: use `'_` for type paths
[INFO] [stderr]     |
[INFO] [stderr] 346 |     pub fn iter_solutions(&mut self) -> Solutions<'_> {
[INFO] [stderr]     |                                                  ++++
[INFO] [stderr] 
[INFO] [stderr] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stderr]    --> src/solver/solver.rs:351:23
[INFO] [stderr]     |
[INFO] [stderr] 351 |     pub fn iter_steps(&mut self) -> SolverSteps {
[INFO] [stderr]     |                       ^^^^^^^^^     ^^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stderr]     |                       |
[INFO] [stderr]     |                       the lifetime is elided here
[INFO] [stderr]     |
[INFO] [stderr]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stderr] help: use `'_` for type paths
[INFO] [stderr]     |
[INFO] [stderr] 351 |     pub fn iter_steps(&mut self) -> SolverSteps<'_> {
[INFO] [stderr]     |                                                ++++
[INFO] [stderr] 
[INFO] [stderr] warning: `exact_cover_solver` (lib) generated 15 warnings (run `cargo fix --lib -p exact_cover_solver` to apply 7 suggestions)
[INFO] [stderr] warning: unused imports: `Duration` and `Instant`
[INFO] [stderr]  --> src/main.rs:1:17
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::time::{Duration, Instant};
[INFO] [stderr]   |                 ^^^^^^^^  ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `bumpalo::Bump`
[INFO] [stderr]  --> src/main.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use bumpalo::Bump;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::thread::sleep`
[INFO] [stderr]  --> src/main.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::thread::sleep;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `itertools::Itertools`
[INFO] [stderr]  --> src/main.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use itertools::Itertools;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `SolverStep`
[INFO] [stderr]  --> src/main.rs:8:48
[INFO] [stderr]   |
[INFO] [stderr] 8 |     ExactCoverSolver, ExactCoverRepresentable, SolverStep
[INFO] [stderr]   |                                                ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `exact_cover_solver` (bin "exact_cover_solver" test) generated 5 warnings (run `cargo fix --bin "exact_cover_solver" --tests` to apply 5 suggestions)
[INFO] [stderr] warning: unused imports: `ExactCoverRepresentable` and `problems::NQueens`
[INFO] [stderr]  --> src/solver/tests/cases.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     problems::NQueens,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 8 |     solver::{ExactCover, ExactCoverSolver, ExactCoverRepresentable,
[INFO] [stderr]   |                                            ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `ExactCoverProblemError`
[INFO] [stderr]   --> src/solver/mod.rs:12:38
[INFO] [stderr]    |
[INFO] [stderr] 12 | pub use problem::{ExactCoverProblem, ExactCoverProblemError,
[INFO] [stderr]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `exact_cover_solver` (lib test) generated 15 warnings (13 duplicates) (run `cargo fix --lib -p exact_cover_solver --tests` to apply 2 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/exact_cover_solver-1f33b69d6a1ef2d7)
[INFO] [stdout] 
[INFO] [stdout] running 15 tests
[INFO] [stdout] test problems::n_queens::test::n_queens_0_equal_to_brute_force ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_2_equal_to_brute_force ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_1_equal_to_brute_force ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_4_equal_to_brute_force ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_3_equal_to_brute_force ... ok
[INFO] [stdout] test solver::tests::cases::check_solutions_knuth_simple ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_5_equal_to_brute_force ... ok
[INFO] [stdout] test solver::tests::cases::check_solutions_zero_by_zero ... ok
[INFO] [stdout] test solver::tests::cases::check_solutions_zero_rows_three_cols_all_secondary ... ok
[INFO] [stdout] test solver::tests::cases::check_solutions_zero_rows_three_cols ... ok
[INFO] [stdout] test solver::problem::test::test_ordered_points_rows ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_6_equal_to_brute_force ... ok
[INFO] [stdout] test solver::tests::cases::check_solutions_three_rows_zero_cols ... FAILED
[INFO] [stdout] test problems::n_queens::test::n_queens_7_equal_to_brute_force ... ok
[INFO] [stdout] test problems::n_queens::test::n_queens_8_equal_to_brute_force ... ok
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- solver::tests::cases::check_solutions_three_rows_zero_cols stdout ----
[INFO] [stdout] 
[INFO] [stdout] thread 'solver::tests::cases::check_solutions_three_rows_zero_cols' (36) panicked at src/solver/problem.rs:79:9:
[INFO] [stdout] attempt to subtract with overflow
[INFO] [stdout] stack backtrace:
[INFO] [stdout]    0:     0x62f3751d96d2 - std::backtrace_rs::backtrace::libunwind::trace::hcab59e1e990fdc24
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
[INFO] [stdout]    1:     0x62f3751d96d2 - std::backtrace_rs::backtrace::trace_unsynchronized::he24cc57f3d2f47b7
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
[INFO] [stdout]    2:     0x62f3751d96d2 - std::sys::backtrace::_print_fmt::hf8d65ede198eeb54
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/backtrace.rs:66:9
[INFO] [stdout]    3:     0x62f3751d96d2 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h67edf0e4d33c343c
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/backtrace.rs:39:26
[INFO] [stdout]    4:     0x62f3751e995f - core::fmt::rt::Argument::fmt::hef94184842aeafdd
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/fmt/rt.rs:173:76
[INFO] [stdout]    5:     0x62f3751e995f - core::fmt::write::hcf0c66b48a8fa606
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/fmt/mod.rs:1468:25
[INFO] [stdout]    6:     0x62f3751a6c41 - std::io::default_write_fmt::h69967ac0ba93195f
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/io/mod.rs:639:11
[INFO] [stdout]    7:     0x62f3751a6c41 - std::io::Write::write_fmt::h8db9396209deaa1c
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/io/mod.rs:1954:13
[INFO] [stdout]    8:     0x62f3751b2ca2 - std::sys::backtrace::BacktraceLock::print::h07e5435aa717b414
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/backtrace.rs:42:9
[INFO] [stdout]    9:     0x62f3751b77ef - std::panicking::default_hook::{{closure}}::h91001850288db5f7
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:301:27
[INFO] [stdout]   10:     0x62f3751b7681 - std::panicking::default_hook::h2346dbb704ef5512
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:325:9
[INFO] [stdout]   11:     0x62f3751759fe - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h18383b2e29377420
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/alloc/src/boxed.rs:1999:9
[INFO] [stdout]   12:     0x62f3751759fe - test::test_main_with_exit_callback::{{closure}}::h272d7ef99aef06dc
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:145:21
[INFO] [stdout]   13:     0x62f3751b7eaf - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h6dba6e441651a0d1
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/alloc/src/boxed.rs:1999:9
[INFO] [stdout]   14:     0x62f3751b7eaf - std::panicking::panic_with_hook::hd2b063a6090d23a4
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:842:13
[INFO] [stdout]   15:     0x62f3751b7cd6 - std::panicking::panic_handler::{{closure}}::he666d95f139a333e
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:700:13
[INFO] [stdout]   16:     0x62f3751b2dd9 - std::sys::backtrace::__rust_end_short_backtrace::h631ad224854ebee5
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/backtrace.rs:174:18
[INFO] [stdout]   17:     0x62f37519b11d - __rustc[1d67440d6e82e4f]::rust_begin_unwind
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:698:5
[INFO] [stdout]   18:     0x62f3751f1320 - core::panicking::panic_fmt::h420ddb7fd73daf53
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/panicking.rs:75:14
[INFO] [stdout]   19:     0x62f3751f0f07 - core::panicking::panic_const::panic_const_sub_overflow::hbe2f8b42373cfcaa
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/panicking.rs:175:17
[INFO] [stdout]   20:     0x62f37514e0e1 - exact_cover_solver::solver::problem::ExactCoverProblem::primary_columns::h92729cd629e27c74
[INFO] [stdout]                                at /opt/rustwide/workdir/src/solver/problem.rs:79:9
[INFO] [stdout]   21:     0x62f37514c587 - exact_cover_solver::solver::solver::ExactCoverSolver::new::h65448cfba6a2ca09
[INFO] [stdout]                                at /opt/rustwide/workdir/src/solver/solver.rs:112:36
[INFO] [stdout]   22:     0x62f37514bd39 - exact_cover_solver::solver::tests::cases::TestCase::assert_solution_match::hd449800bbf4a633c
[INFO] [stdout]                                at /opt/rustwide/workdir/src/solver/tests/cases.rs:17:27
[INFO] [stdout]   23:     0x62f37514b6db - exact_cover_solver::solver::tests::cases::check_solutions_three_rows_zero_cols::h0b5ffe0b5a8a61a6
[INFO] [stdout]                                at /opt/rustwide/workdir/src/solver/tests/cases.rs:117:76
[INFO] [stdout]   24:     0x62f37514b6f7 - exact_cover_solver::solver::tests::cases::check_solutions_three_rows_zero_cols::{{closure}}::h11a049735d4d36f1
[INFO] [stdout]                                at /opt/rustwide/workdir/src/solver/tests/cases.rs:117:50
[INFO] [stdout]   25:     0x62f375143d56 - core::ops::function::FnOnce::call_once::h00f1ffef935d21c2
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   26:     0x62f3751757bb - core::ops::function::FnOnce::call_once::h70887edf07a630ba
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   27:     0x62f3751757bb - test::__rust_begin_short_backtrace::h27763c4cbbdb8601
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:663:18
[INFO] [stdout]   28:     0x62f37518b425 - test::run_test_in_process::{{closure}}::h4dc8bc6d5e3924d3
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:686:74
[INFO] [stdout]   29:     0x62f37518b425 - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::h75905e8ffe81974f
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/panic/unwind_safe.rs:274:9
[INFO] [stdout]   30:     0x62f37518b425 - std::panicking::catch_unwind::do_call::h0bc60366ba66eba5
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:590:40
[INFO] [stdout]   31:     0x62f37518b425 - std::panicking::catch_unwind::hae1ec7bf94407afa
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:553:19
[INFO] [stdout]   32:     0x62f37518b425 - std::panic::catch_unwind::h0f4ff4773d84d3cd
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panic.rs:359:14
[INFO] [stdout]   33:     0x62f37518b425 - test::run_test_in_process::h03fbc77ae48b3f10
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:686:27
[INFO] [stdout]   34:     0x62f37518b425 - test::run_test::{{closure}}::h83476a9c453dc4d3
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:607:43
[INFO] [stdout]   35:     0x62f375161c14 - test::run_test::{{closure}}::h515482ad1e7fe7de
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/test/src/lib.rs:637:41
[INFO] [stdout]   36:     0x62f375161c14 - std::sys::backtrace::__rust_begin_short_backtrace::hed09f6ac5fe9d647
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/backtrace.rs:158:18
[INFO] [stdout]   37:     0x62f3751654da - std::thread::Builder::spawn_unchecked_::{{closure}}::{{closure}}::h988e2cd969319888
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/thread/mod.rs:559:17
[INFO] [stdout]   38:     0x62f3751654da - <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once::hd70e28dc46ec20be
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/panic/unwind_safe.rs:274:9
[INFO] [stdout]   39:     0x62f3751654da - std::panicking::catch_unwind::do_call::hdc29e11311eb7655
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:590:40
[INFO] [stdout]   40:     0x62f3751654da - std::panicking::catch_unwind::h9e402d6a96fef41c
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panicking.rs:553:19
[INFO] [stdout]   41:     0x62f3751654da - std::panic::catch_unwind::h9213c0c54aec70e0
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/panic.rs:359:14
[INFO] [stdout]   42:     0x62f3751654da - std::thread::Builder::spawn_unchecked_::{{closure}}::h6262965869ed2b87
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/thread/mod.rs:557:30
[INFO] [stdout]   43:     0x62f3751654da - core::ops::function::FnOnce::call_once{{vtable.shim}}::h05c05ed02619e462
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/core/src/ops/function.rs:250:5
[INFO] [stdout]   44:     0x62f3751adf3f - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h2044e71c41d3958a
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/alloc/src/boxed.rs:1985:9
[INFO] [stdout]   45:     0x62f3751adf3f - std::sys::thread::unix::Thread::new::thread_start::hf277835320aa8e5a
[INFO] [stdout]                                at /rustc/bb624dcb4c8ab987e10c0808d92d76f3b84dd117/library/std/src/sys/thread/unix.rs:126:17
[INFO] [stdout]   46:     0x7f44cfeb6aa4 - <unknown>
[INFO] [stdout]   47:     0x7f44cff43a34 - clone
[INFO] [stdout]   48:                0x0 - <unknown>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     solver::tests::cases::check_solutions_three_rows_zero_cols
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 14 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.66s
[INFO] [stdout] 
[INFO] [stderr] error: test failed, to rerun pass `--lib`
[INFO] running `Command { std: "docker" "inspect" "ce02119dd4e80cc2dc0c908ceab5b870ac87d1278fd81e3855a0f42683b55a55", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ce02119dd4e80cc2dc0c908ceab5b870ac87d1278fd81e3855a0f42683b55a55", kill_on_drop: false }`
[INFO] [stdout] ce02119dd4e80cc2dc0c908ceab5b870ac87d1278fd81e3855a0f42683b55a55
