[INFO] updating cached repository https://github.com/Nalleyer/SudokuSolver
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/mnt/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4d0677b09b28157087276910f7ddd483eb583bd2
[INFO] checking Nalleyer/SudokuSolver against master#c9edc02e8320a9e5799d185910ece7d491f524e6 for pr-64398
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2FSudokuSolver" "work/builds/worker-5/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Nalleyer/SudokuSolver on toolchain c9edc02e8320a9e5799d185910ece7d491f524e6-alt
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/Nalleyer/SudokuSolver
[INFO] finished tweaking git repo https://github.com/Nalleyer/SudokuSolver
[INFO] tweaked toml for git repo https://github.com/Nalleyer/SudokuSolver written to work/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/Nalleyer/SudokuSolver already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-5/source:/opt/rustwide/workdir:ro,Z" "-v" "/mnt/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 0463844d87dfada9496088445a3285ede31ad85fba3540f981246c7925a8a660
[INFO] running `"docker" "start" "-a" "0463844d87dfada9496088445a3285ede31ad85fba3540f981246c7925a8a660"`
[INFO] [stderr]     Checking sudoku_solver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `View`
[INFO] [stderr]  --> src/solver.rs:1:36
[INFO] [stderr]   |
[INFO] [stderr] 1 | use crate::sudoku::{Sudoku, Value, View};
[INFO] [stderr]   |                                    ^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/solver.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::FromIterator`
[INFO] [stderr]  --> src/solver.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::iter::FromIterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `View`
[INFO] [stderr]  --> src/solver.rs:1:36
[INFO] [stderr]   |
[INFO] [stderr] 1 | use crate::sudoku::{Sudoku, Value, View};
[INFO] [stderr]   |                                    ^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/solver.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::FromIterator`
[INFO] [stderr]  --> src/solver.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::iter::FromIterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:164:13
[INFO] [stderr]     |
[INFO] [stderr] 164 |         let mut sdk = Sudoku::new(&s_str).unwrap();
[INFO] [stderr]     |             ----^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:165:13
[INFO] [stderr]     |
[INFO] [stderr] 165 |         let mut sdk2 = Sudoku::new(&s_str).unwrap();
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Value`
[INFO] [stderr]  --> src/bin/main.rs:5:37
[INFO] [stderr]   |
[INFO] [stderr] 5 | use sudoku_solver::{Solver, Sudoku, Value};
[INFO] [stderr]   |                                     ^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Value`
[INFO] [stderr]  --> src/bin/main.rs:5:37
[INFO] [stderr]   |
[INFO] [stderr] 5 | use sudoku_solver::{Solver, Sudoku, Value};
[INFO] [stderr]   |                                     ^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.40s
[INFO] running `"docker" "inspect" "0463844d87dfada9496088445a3285ede31ad85fba3540f981246c7925a8a660"`
[INFO] running `"docker" "rm" "-f" "0463844d87dfada9496088445a3285ede31ad85fba3540f981246c7925a8a660"`
[INFO] [stdout] 0463844d87dfada9496088445a3285ede31ad85fba3540f981246c7925a8a660