[INFO] updating cached repository fchiba/rust_sudoku_solver
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/fchiba/rust_sudoku_solver
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/fchiba/rust_sudoku_solver" "work/ex/clippy-test-run/sources/stable/gh/fchiba/rust_sudoku_solver"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/fchiba/rust_sudoku_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/fchiba/rust_sudoku_solver" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/fchiba/rust_sudoku_solver"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/fchiba/rust_sudoku_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4c12dd18ecca2c74c359b7d95bb634feb0d84c50
[INFO] sha for GitHub repo fchiba/rust_sudoku_solver: 4c12dd18ecca2c74c359b7d95bb634feb0d84c50
[INFO] validating manifest of fchiba/rust_sudoku_solver on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of fchiba/rust_sudoku_solver on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing fchiba/rust_sudoku_solver
[INFO] finished frobbing fchiba/rust_sudoku_solver
[INFO] frobbed toml for fchiba/rust_sudoku_solver written to work/ex/clippy-test-run/sources/stable/gh/fchiba/rust_sudoku_solver/Cargo.toml
[INFO] started frobbing fchiba/rust_sudoku_solver
[INFO] finished frobbing fchiba/rust_sudoku_solver
[INFO] frobbed toml for fchiba/rust_sudoku_solver written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/fchiba/rust_sudoku_solver/Cargo.toml
[INFO] crate fchiba/rust_sudoku_solver has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting fchiba/rust_sudoku_solver against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-6/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/gh/fchiba/rust_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" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 8a8c690c8349911009ae9874e3d8453469bb617a7adf34dcd41a027f9a865c03
[INFO] running `"docker" "start" "-a" "8a8c690c8349911009ae9874e3d8453469bb617a7adf34dcd41a027f9a865c03"`
[INFO] [stderr]     Checking sudokurust v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: using `println!("")`
[INFO] [stderr]    --> src/main.rs:155:9
[INFO] [stderr]     |
[INFO] [stderr] 155 |         println!("")
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: replace it with: `println!()`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::println_empty_string)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#println_empty_string
[INFO] [stderr] 
[INFO] [stderr] warning: using `println!("")`
[INFO] [stderr]    --> src/main.rs:155:9
[INFO] [stderr]     |
[INFO] [stderr] 155 |         println!("")
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: replace it with: `println!()`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::println_empty_string)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#println_empty_string
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/main.rs:43:9
[INFO] [stderr]    |
[INFO] [stderr] 43 | /         if let &None = num {
[INFO] [stderr] 44 | |             // filter candidates
[INFO] [stderr] 45 | |             let nums : Vec<usize> = candidates[idx].iter().enumerate().filter_map(|(num,val)| if *val {Some(num)} else {None}).collect();
[INFO] [stderr] 46 | |             
[INFO] [stderr] ...  |
[INFO] [stderr] 98 | |             }
[INFO] [stderr] 99 | |         }
[INFO] [stderr]    | |_________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 43 |         if let None = *num {
[INFO] [stderr]    |                ^^^^   ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/main.rs:147:24
[INFO] [stderr]     |
[INFO] [stderr] 147 | fn print_board(board : &Board) {
[INFO] [stderr]     |                        ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/main.rs:162:9
[INFO] [stderr]     |
[INFO] [stderr] 162 | /         if let &Some(number) = num {
[INFO] [stderr] 163 | |             put_number(idx, number, &mut candidates)
[INFO] [stderr] 164 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 162 |         if let Some(number) = *num {
[INFO] [stderr]     |                ^^^^^^^^^^^^   ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: length comparison to zero
[INFO] [stderr]    --> src/main.rs:169:12
[INFO] [stderr]     |
[INFO] [stderr] 169 |         if founds.len() == 0 {
[INFO] [stderr]     |            ^^^^^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `founds.is_empty()`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/main.rs:43:9
[INFO] [stderr]    |
[INFO] [stderr] 43 | /         if let &None = num {
[INFO] [stderr] 44 | |             // filter candidates
[INFO] [stderr] 45 | |             let nums : Vec<usize> = candidates[idx].iter().enumerate().filter_map(|(num,val)| if *val {Some(num)} else {None}).collect();
[INFO] [stderr] 46 | |             
[INFO] [stderr] ...  |
[INFO] [stderr] 98 | |             }
[INFO] [stderr] 99 | |         }
[INFO] [stderr]    | |_________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 43 |         if let None = *num {
[INFO] [stderr]    |                ^^^^   ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/main.rs:147:24
[INFO] [stderr]     |
[INFO] [stderr] 147 | fn print_board(board : &Board) {
[INFO] [stderr]     |                        ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/main.rs:162:9
[INFO] [stderr]     |
[INFO] [stderr] 162 | /         if let &Some(number) = num {
[INFO] [stderr] 163 | |             put_number(idx, number, &mut candidates)
[INFO] [stderr] 164 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 162 |         if let Some(number) = *num {
[INFO] [stderr]     |                ^^^^^^^^^^^^   ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: length comparison to zero
[INFO] [stderr]    --> src/main.rs:169:12
[INFO] [stderr]     |
[INFO] [stderr] 169 |         if founds.len() == 0 {
[INFO] [stderr]     |            ^^^^^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `founds.is_empty()`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.91s
[INFO] running `"docker" "inspect" "8a8c690c8349911009ae9874e3d8453469bb617a7adf34dcd41a027f9a865c03"`
[INFO] running `"docker" "rm" "-f" "8a8c690c8349911009ae9874e3d8453469bb617a7adf34dcd41a027f9a865c03"`
[INFO] [stdout] 8a8c690c8349911009ae9874e3d8453469bb617a7adf34dcd41a027f9a865c03