[INFO] cloning repository https://github.com/Nalleyer/SudokuSolver
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Nalleyer/SudokuSolver" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2FSudokuSolver", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2FSudokuSolver'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4d0677b09b28157087276910f7ddd483eb583bd2
[INFO] checking Nalleyer/SudokuSolver/4d0677b09b28157087276910f7ddd483eb583bd2 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2FSudokuSolver" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Nalleyer/SudokuSolver on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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 /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Nalleyer/SudokuSolver 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" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c0282770afe831c6a483cccc72ce7596d2819781c0b65189baa668913f9f2493
[INFO] running `Command { std: "docker" "start" "-a" "c0282770afe831c6a483cccc72ce7596d2819781c0b65189baa668913f9f2493", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c0282770afe831c6a483cccc72ce7596d2819781c0b65189baa668913f9f2493", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c0282770afe831c6a483cccc72ce7596d2819781c0b65189baa668913f9f2493", kill_on_drop: false }`
[INFO] [stdout] c0282770afe831c6a483cccc72ce7596d2819781c0b65189baa668913f9f2493
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8c05f0636e9b627b9455220529403ffc79d96bced04d84e2d83883487b477ca5
[INFO] running `Command { std: "docker" "start" "-a" "8c05f0636e9b627b9455220529403ffc79d96bced04d84e2d83883487b477ca5", kill_on_drop: false }`
[INFO] [stderr]     Checking sudoku_solver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `View`
[INFO] [stdout]  --> src/solver.rs:1:36
[INFO] [stdout]   |
[INFO] [stdout] 1 | use crate::sudoku::{Sudoku, Value, View};
[INFO] [stdout]   |                                    ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/solver.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter::FromIterator`
[INFO] [stdout]  --> src/solver.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::iter::FromIterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `View`
[INFO] [stdout]  --> src/solver.rs:1:36
[INFO] [stdout]   |
[INFO] [stdout] 1 | use crate::sudoku::{Sudoku, Value, View};
[INFO] [stdout]   |                                    ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashSet`
[INFO] [stdout]  --> src/solver.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::collections::HashSet;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter::FromIterator`
[INFO] [stdout]  --> src/solver.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::iter::FromIterator;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/solver.rs:164:13
[INFO] [stdout]     |
[INFO] [stdout] 164 |         let mut sdk = Sudoku::new(&s_str).unwrap();
[INFO] [stdout]     |             ----^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/solver.rs:165:13
[INFO] [stdout]     |
[INFO] [stdout] 165 |         let mut sdk2 = Sudoku::new(&s_str).unwrap();
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Value`
[INFO] [stdout]  --> src/bin/main.rs:5:37
[INFO] [stdout]   |
[INFO] [stdout] 5 | use sudoku_solver::{Solver, Sudoku, Value};
[INFO] [stdout]   |                                     ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Value`
[INFO] [stdout]  --> src/bin/main.rs:5:37
[INFO] [stdout]   |
[INFO] [stdout] 5 | use sudoku_solver::{Solver, Sudoku, Value};
[INFO] [stdout]   |                                     ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.52s
[INFO] running `Command { std: "docker" "inspect" "8c05f0636e9b627b9455220529403ffc79d96bced04d84e2d83883487b477ca5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8c05f0636e9b627b9455220529403ffc79d96bced04d84e2d83883487b477ca5", kill_on_drop: false }`
[INFO] [stdout] 8c05f0636e9b627b9455220529403ffc79d96bced04d84e2d83883487b477ca5