[INFO] updating cached repository ErikPartridge/sudoku-generator
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/ErikPartridge/sudoku-generator
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/ErikPartridge/sudoku-generator" "work/ex/pr-62181/sources/master#6ea4036cd20a4b1ab1d56e555108c21735ff6946/gh/ErikPartridge/sudoku-generator"`
[INFO] [stderr] Cloning into 'work/ex/pr-62181/sources/master#6ea4036cd20a4b1ab1d56e555108c21735ff6946/gh/ErikPartridge/sudoku-generator'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/ErikPartridge/sudoku-generator" "work/ex/pr-62181/sources/try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc/gh/ErikPartridge/sudoku-generator"`
[INFO] [stderr] Cloning into 'work/ex/pr-62181/sources/try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc/gh/ErikPartridge/sudoku-generator'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] abf3fb1b85c4b234c8d333af646357ec631d53d2
[INFO] sha for GitHub repo ErikPartridge/sudoku-generator: abf3fb1b85c4b234c8d333af646357ec631d53d2
[INFO] validating manifest of ErikPartridge/sudoku-generator on toolchain master#6ea4036cd20a4b1ab1d56e555108c21735ff6946
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+6ea4036cd20a4b1ab1d56e555108c21735ff6946-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of ErikPartridge/sudoku-generator on toolchain try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+003a7b6b5753e8509fdfe7949d4f0873ba71e4fc-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing ErikPartridge/sudoku-generator
[INFO] finished frobbing ErikPartridge/sudoku-generator
[INFO] frobbed toml for ErikPartridge/sudoku-generator written to work/ex/pr-62181/sources/master#6ea4036cd20a4b1ab1d56e555108c21735ff6946/gh/ErikPartridge/sudoku-generator/Cargo.toml
[INFO] started frobbing ErikPartridge/sudoku-generator
[INFO] finished frobbing ErikPartridge/sudoku-generator
[INFO] frobbed toml for ErikPartridge/sudoku-generator written to work/ex/pr-62181/sources/try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc/gh/ErikPartridge/sudoku-generator/Cargo.toml
[INFO] crate ErikPartridge/sudoku-generator already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+6ea4036cd20a4b1ab1d56e555108c21735ff6946-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+003a7b6b5753e8509fdfe7949d4f0873ba71e4fc-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking ErikPartridge/sudoku-generator against try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc for pr-62181
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-62181/worker-7/try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-62181/sources/try#003a7b6b5753e8509fdfe7949d4f0873ba71e4fc/gh/ErikPartridge/sudoku-generator:/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" "+003a7b6b5753e8509fdfe7949d4f0873ba71e4fc-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 6b4f45a9bbc92cc79b8ebb933096d8fc79600e59c45c4b70c93b8519d62954f7
[INFO] running `"docker" "start" "-a" "6b4f45a9bbc92cc79b8ebb933096d8fc79600e59c45c4b70c93b8519d62954f7"`
[INFO] [stderr]     Checking sudoku-generator v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `freedom::Freedom`
[INFO] [stderr]  --> src/main.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use freedom::Freedom;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `problem::Problem`
[INFO] [stderr]  --> src/main.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use problem::Problem;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/freedom.rs:28:9
[INFO] [stderr]    |
[INFO] [stderr] 28 |     for j in 0..3 {
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_j`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ORDER`
[INFO] [stderr]  --> src/freedom.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | const ORDER: u8 = 3;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `DIM`
[INFO] [stderr]  --> src/freedom.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | const DIM: u8 = ORDER * ORDER;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ELEMENTS`
[INFO] [stderr]  --> src/freedom.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | const ELEMENTS: u8 = DIM * DIM;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ALL_VALUES`
[INFO] [stderr]  --> src/freedom.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | const ALL_VALUES: u16 = (1 << DIM) - 1;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Freedom`
[INFO] [stderr]  --> src/freedom.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | pub struct Freedom {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `singleton`
[INFO] [stderr]   --> src/freedom.rs:11:1
[INFO] [stderr]    |
[INFO] [stderr] 11 | fn singleton(v: u16) -> u16 {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `freedom_eliminate`
[INFO] [stderr]   --> src/freedom.rs:16:1
[INFO] [stderr]    |
[INFO] [stderr] 16 | fn freedom_eliminate(f: &Freedom, col: u16, row: u16, value: u16) -> Freedom {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_freedom`
[INFO] [stderr]   --> src/freedom.rs:38:1
[INFO] [stderr]    |
[INFO] [stderr] 38 | fn create_freedom(problem: &Problem) -> Freedom {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `sanity_check`
[INFO] [stderr]   --> src/freedom.rs:52:1
[INFO] [stderr]    |
[INFO] [stderr] 52 | fn sanity_check(problem: &Problem, freedom: &Freedom) -> bool {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `search_least_free`
[INFO] [stderr]   --> src/freedom.rs:63:1
[INFO] [stderr]    |
[INFO] [stderr] 63 | fn search_least_free(problem: &Problem, freedom: &Freedom) -> u16 {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Problem`
[INFO] [stderr]  --> src/problem.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | pub struct Problem {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `freedom::Freedom`
[INFO] [stderr]  --> src/main.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use freedom::Freedom;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `problem::Problem`
[INFO] [stderr]  --> src/main.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use problem::Problem;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/freedom.rs:28:9
[INFO] [stderr]    |
[INFO] [stderr] 28 |     for j in 0..3 {
[INFO] [stderr]    |         ^ help: consider prefixing with an underscore: `_j`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ORDER`
[INFO] [stderr]  --> src/freedom.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | const ORDER: u8 = 3;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `DIM`
[INFO] [stderr]  --> src/freedom.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | const DIM: u8 = ORDER * ORDER;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ELEMENTS`
[INFO] [stderr]  --> src/freedom.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | const ELEMENTS: u8 = DIM * DIM;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `ALL_VALUES`
[INFO] [stderr]  --> src/freedom.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | const ALL_VALUES: u16 = (1 << DIM) - 1;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Freedom`
[INFO] [stderr]  --> src/freedom.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | pub struct Freedom {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `singleton`
[INFO] [stderr]   --> src/freedom.rs:11:1
[INFO] [stderr]    |
[INFO] [stderr] 11 | fn singleton(v: u16) -> u16 {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `freedom_eliminate`
[INFO] [stderr]   --> src/freedom.rs:16:1
[INFO] [stderr]    |
[INFO] [stderr] 16 | fn freedom_eliminate(f: &Freedom, col: u16, row: u16, value: u16) -> Freedom {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_freedom`
[INFO] [stderr]   --> src/freedom.rs:38:1
[INFO] [stderr]    |
[INFO] [stderr] 38 | fn create_freedom(problem: &Problem) -> Freedom {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `sanity_check`
[INFO] [stderr]   --> src/freedom.rs:52:1
[INFO] [stderr]    |
[INFO] [stderr] 52 | fn sanity_check(problem: &Problem, freedom: &Freedom) -> bool {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `search_least_free`
[INFO] [stderr]   --> src/freedom.rs:63:1
[INFO] [stderr]    |
[INFO] [stderr] 63 | fn search_least_free(problem: &Problem, freedom: &Freedom) -> u16 {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Problem`
[INFO] [stderr]  --> src/problem.rs:1:1
[INFO] [stderr]   |
[INFO] [stderr] 1 | pub struct Problem {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.10s
[INFO] running `"docker" "inspect" "6b4f45a9bbc92cc79b8ebb933096d8fc79600e59c45c4b70c93b8519d62954f7"`
[INFO] running `"docker" "rm" "-f" "6b4f45a9bbc92cc79b8ebb933096d8fc79600e59c45c4b70c93b8519d62954f7"`
[INFO] [stdout] 6b4f45a9bbc92cc79b8ebb933096d8fc79600e59c45c4b70c93b8519d62954f7