[INFO] cloning repository EthanTheMaster/sudoku_solver
[INFO] running `"git" "clone" "--bare" "git://github.com/EthanTheMaster/sudoku_solver.git" "work/cache/sources/gh/EthanTheMaster/sudoku_solver"`
[INFO] [stderr] Cloning into bare repository 'work/cache/sources/gh/EthanTheMaster/sudoku_solver'...
[INFO] running `"git" "clone" "work/cache/sources/gh/EthanTheMaster/sudoku_solver" "work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver"`
[INFO] [stderr] Cloning into 'work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/EthanTheMaster/sudoku_solver" "work/ex/pr-61629/sources/try#e212b7d492c96d3837691ba29d32d5f468933fb8/gh/EthanTheMaster/sudoku_solver"`
[INFO] [stderr] Cloning into 'work/ex/pr-61629/sources/try#e212b7d492c96d3837691ba29d32d5f468933fb8/gh/EthanTheMaster/sudoku_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] f0d269d3d954a9b6c82d6d0856dd0175544949f6
[INFO] sha for GitHub repo EthanTheMaster/sudoku_solver: f0d269d3d954a9b6c82d6d0856dd0175544949f6
[INFO] validating manifest of EthanTheMaster/sudoku_solver on toolchain master#c8865d8e195813ade6b84434ac9f8850e7112d1a
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of EthanTheMaster/sudoku_solver on toolchain try#e212b7d492c96d3837691ba29d32d5f468933fb8
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e212b7d492c96d3837691ba29d32d5f468933fb8-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing EthanTheMaster/sudoku_solver
[INFO] finished frobbing EthanTheMaster/sudoku_solver
[INFO] frobbed toml for EthanTheMaster/sudoku_solver written to work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver/Cargo.toml
[INFO] started frobbing EthanTheMaster/sudoku_solver
[INFO] finished frobbing EthanTheMaster/sudoku_solver
[INFO] frobbed toml for EthanTheMaster/sudoku_solver written to work/ex/pr-61629/sources/try#e212b7d492c96d3837691ba29d32d5f468933fb8/gh/EthanTheMaster/sudoku_solver/Cargo.toml
[INFO] crate EthanTheMaster/sudoku_solver already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e212b7d492c96d3837691ba29d32d5f468933fb8-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing EthanTheMaster/sudoku_solver against master#c8865d8e195813ade6b84434ac9f8850e7112d1a for pr-61629
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-61629/worker-2/master#c8865d8e195813ade6b84434ac9f8850e7112d1a:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "build" "--frozen"`
[INFO] [stdout] eb950ebf1224771fe66291be948c24ee18041990296756e8e6b2b8ef3671fdf2
[INFO] running `"docker" "start" "-a" "eb950ebf1224771fe66291be948c24ee18041990296756e8e6b2b8ef3671fdf2"`
[INFO] [stderr]    Compiling sudoku_solver v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `operation`
[INFO] [stderr]   --> src/sudoku_solver_dancinglinks/mod.rs:96:32
[INFO] [stderr]    |
[INFO] [stderr] 96 |         if let NodeType::Field(operation, column_header_id) = node_type {
[INFO] [stderr]    |                                ^^^^^^^^^ help: consider prefixing with an underscore: `_operation`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:100:48
[INFO] [stderr]     |
[INFO] [stderr] 100 |                 NodeType::ColumnHeader(ref mut constraint, ref mut size) => {
[INFO] [stderr]     |                                                ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `operation`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:119:29
[INFO] [stderr]     |
[INFO] [stderr] 119 |             NodeType::Field(operation, column_header_id) => {
[INFO] [stderr]     |                             ^^^^^^^^^ help: consider prefixing with an underscore: `_operation`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:127:36
[INFO] [stderr]     |
[INFO] [stderr] 127 |             NodeType::ColumnHeader(constraint, size) => {
[INFO] [stderr]     |                                    ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:226:44
[INFO] [stderr]     |
[INFO] [stderr] 226 |                     NodeType::ColumnHeader(constraint, ref mut size) => {
[INFO] [stderr]     |                                            ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:269:44
[INFO] [stderr]     |
[INFO] [stderr] 269 |                     NodeType::ColumnHeader(constraint, ref mut size) => {
[INFO] [stderr]     |                                            ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `idx`
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:35:24
[INFO] [stderr]    |
[INFO] [stderr] 35 |             .filter(|&(idx, val)| {
[INFO] [stderr]    |                        ^^^ help: consider prefixing with an underscore: `_idx`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `val`
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:37:27
[INFO] [stderr]    |
[INFO] [stderr] 37 |             }).map(|(idx, val)| {
[INFO] [stderr]    |                           ^^^ help: consider prefixing with an underscore: `_val`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:34:13
[INFO] [stderr]    |
[INFO] [stderr] 34 |         let mut blank_positions: Vec<usize> = self.board.iter().enumerate()
[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]     Finished dev [unoptimized + debuginfo] target(s) in 2.19s
[INFO] running `"docker" "inspect" "eb950ebf1224771fe66291be948c24ee18041990296756e8e6b2b8ef3671fdf2"`
[INFO] running `"docker" "rm" "-f" "eb950ebf1224771fe66291be948c24ee18041990296756e8e6b2b8ef3671fdf2"`
[INFO] [stdout] eb950ebf1224771fe66291be948c24ee18041990296756e8e6b2b8ef3671fdf2
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-61629/worker-2/master#c8865d8e195813ade6b84434ac9f8850e7112d1a:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "test" "--frozen" "--no-run"`
[INFO] [stdout] c1b72ae45b750889a16508cb96e566480c9cb4e97af7ae3006643a6ec8928c9d
[INFO] running `"docker" "start" "-a" "c1b72ae45b750889a16508cb96e566480c9cb4e97af7ae3006643a6ec8928c9d"`
[INFO] [stderr]    Compiling sudoku_solver v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `operation`
[INFO] [stderr]   --> src/sudoku_solver_dancinglinks/mod.rs:96:32
[INFO] [stderr]    |
[INFO] [stderr] 96 |         if let NodeType::Field(operation, column_header_id) = node_type {
[INFO] [stderr]    |                                ^^^^^^^^^ help: consider prefixing with an underscore: `_operation`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:100:48
[INFO] [stderr]     |
[INFO] [stderr] 100 |                 NodeType::ColumnHeader(ref mut constraint, ref mut size) => {
[INFO] [stderr]     |                                                ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `operation`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:119:29
[INFO] [stderr]     |
[INFO] [stderr] 119 |             NodeType::Field(operation, column_header_id) => {
[INFO] [stderr]     |                             ^^^^^^^^^ help: consider prefixing with an underscore: `_operation`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:127:36
[INFO] [stderr]     |
[INFO] [stderr] 127 |             NodeType::ColumnHeader(constraint, size) => {
[INFO] [stderr]     |                                    ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:226:44
[INFO] [stderr]     |
[INFO] [stderr] 226 |                     NodeType::ColumnHeader(constraint, ref mut size) => {
[INFO] [stderr]     |                                            ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `constraint`
[INFO] [stderr]    --> src/sudoku_solver_dancinglinks/mod.rs:269:44
[INFO] [stderr]     |
[INFO] [stderr] 269 |                     NodeType::ColumnHeader(constraint, ref mut size) => {
[INFO] [stderr]     |                                            ^^^^^^^^^^ help: consider prefixing with an underscore: `_constraint`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `idx`
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:35:24
[INFO] [stderr]    |
[INFO] [stderr] 35 |             .filter(|&(idx, val)| {
[INFO] [stderr]    |                        ^^^ help: consider prefixing with an underscore: `_idx`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `val`
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:37:27
[INFO] [stderr]    |
[INFO] [stderr] 37 |             }).map(|(idx, val)| {
[INFO] [stderr]    |                           ^^^ help: consider prefixing with an underscore: `_val`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/sudoku_solver_backtrack/mod.rs:34:13
[INFO] [stderr]    |
[INFO] [stderr] 34 |         let mut blank_positions: Vec<usize> = self.board.iter().enumerate()
[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]     Finished dev [unoptimized + debuginfo] target(s) in 0.93s
[INFO] running `"docker" "inspect" "c1b72ae45b750889a16508cb96e566480c9cb4e97af7ae3006643a6ec8928c9d"`
[INFO] running `"docker" "rm" "-f" "c1b72ae45b750889a16508cb96e566480c9cb4e97af7ae3006643a6ec8928c9d"`
[INFO] [stdout] c1b72ae45b750889a16508cb96e566480c9cb4e97af7ae3006643a6ec8928c9d
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-61629/worker-2/master#c8865d8e195813ade6b84434ac9f8850e7112d1a:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/gh/EthanTheMaster/sudoku_solver:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "test" "--frozen"`
[INFO] [stdout] e0a7decdd2dc15a03191617d2fbfde8d27cdcf79d5a1c8d944572f91f2b8c438
[INFO] running `"docker" "start" "-a" "e0a7decdd2dc15a03191617d2fbfde8d27cdcf79d5a1c8d944572f91f2b8c438"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/sudoku_solver-e7781a7e15885f25
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "e0a7decdd2dc15a03191617d2fbfde8d27cdcf79d5a1c8d944572f91f2b8c438"`
[INFO] running `"docker" "rm" "-f" "e0a7decdd2dc15a03191617d2fbfde8d27cdcf79d5a1c8d944572f91f2b8c438"`
[INFO] [stdout] e0a7decdd2dc15a03191617d2fbfde8d27cdcf79d5a1c8d944572f91f2b8c438