[INFO] cloning repository chc4/minesweeper
[INFO] running `"git" "clone" "--bare" "git://github.com/chc4/minesweeper.git" "work/cache/sources/gh/chc4/minesweeper"`
[INFO] [stderr] Cloning into bare repository 'work/cache/sources/gh/chc4/minesweeper'...
[INFO] running `"git" "clone" "work/cache/sources/gh/chc4/minesweeper" "work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/gh/chc4/minesweeper"`
[INFO] [stderr] Cloning into 'work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/gh/chc4/minesweeper'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/chc4/minesweeper" "work/ex/pr-58899/sources/try#290ac7b29f41ff9fa5232f9a1116ea71a3501063/gh/chc4/minesweeper"`
[INFO] [stderr] Cloning into 'work/ex/pr-58899/sources/try#290ac7b29f41ff9fa5232f9a1116ea71a3501063/gh/chc4/minesweeper'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] ce5b54dc6901a490016be5f90e230e990ddbb2cd
[INFO] sha for GitHub repo chc4/minesweeper: ce5b54dc6901a490016be5f90e230e990ddbb2cd
[INFO] validating manifest of chc4/minesweeper on toolchain master#c0086b9e8972fef9fd4af24bae20d45021ed06c6
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of chc4/minesweeper on toolchain try#290ac7b29f41ff9fa5232f9a1116ea71a3501063
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+290ac7b29f41ff9fa5232f9a1116ea71a3501063-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing chc4/minesweeper
[INFO] finished frobbing chc4/minesweeper
[INFO] frobbed toml for chc4/minesweeper written to work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/gh/chc4/minesweeper/Cargo.toml
[INFO] started frobbing chc4/minesweeper
[INFO] finished frobbing chc4/minesweeper
[INFO] frobbed toml for chc4/minesweeper written to work/ex/pr-58899/sources/try#290ac7b29f41ff9fa5232f9a1116ea71a3501063/gh/chc4/minesweeper/Cargo.toml
[INFO] crate chc4/minesweeper has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+290ac7b29f41ff9fa5232f9a1116ea71a3501063-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking chc4/minesweeper against master#c0086b9e8972fef9fd4af24bae20d45021ed06c6 for pr-58899
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58899/worker-7/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58899/sources/master#c0086b9e8972fef9fd4af24bae20d45021ed06c6/gh/chc4/minesweeper:/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" "+c0086b9e8972fef9fd4af24bae20d45021ed06c6-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] ca7ad85fccb6be1bc22fef83856c39d5999599595f05ad0061a1ea3ecb17a658
[INFO] running `"docker" "start" "-a" "ca7ad85fccb6be1bc22fef83856c39d5999599595f05ad0061a1ea3ecb17a658"`
[INFO] [stderr]     Checking minesweeper v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::io`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::io;
[INFO] [stderr]   |     ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::io`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::io;
[INFO] [stderr]   |     ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `stdin`
[INFO] [stderr]    --> src/main.rs:183:9
[INFO] [stderr]     |
[INFO] [stderr] 183 |     let stdin = std::io::stdin();
[INFO] [stderr]     |         ^^^^^ help: consider prefixing with an underscore: `_stdin`
[INFO] [stderr] warning: unused variable: `stdin`
[INFO] [stderr]    --> src/main.rs:183:9
[INFO] [stderr]     |
[INFO] [stderr] 183 |     let stdin = std::io::stdin();
[INFO] [stderr]     |         ^^^^^ help: consider prefixing with an underscore: `_stdin`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]   --> src/main.rs:56:13
[INFO] [stderr]    |
[INFO] [stderr] 56 |         for i in 0..y {
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_i`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/main.rs:58:17
[INFO] [stderr]    |
[INFO] [stderr] 58 |             for j in 0..x {
[INFO] [stderr]    |                 ^ help: consider prefixing with an underscore: `_j`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `count`
[INFO] [stderr]    --> src/main.rs:108:36
[INFO] [stderr]     |
[INFO] [stderr] 108 |         if let Slot::Empty(visible,count) = slot {
[INFO] [stderr]     |                                    ^^^^^ help: consider prefixing with an underscore: `_count`
[INFO] [stderr] 
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]   --> src/main.rs:56:13
[INFO] [stderr]    |
[INFO] [stderr] 56 |         for i in 0..y {
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_i`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `j`
[INFO] [stderr]   --> src/main.rs:58:17
[INFO] [stderr]    |
[INFO] [stderr] 58 |             for j in 0..x {
[INFO] [stderr]    |                 ^ help: consider prefixing with an underscore: `_j`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `count`
[INFO] [stderr]    --> src/main.rs:108:36
[INFO] [stderr]     |
[INFO] [stderr] 108 |         if let Slot::Empty(visible,count) = slot {
[INFO] [stderr]     |                                    ^^^^^ help: consider prefixing with an underscore: `_count`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:30:9
[INFO] [stderr]    |
[INFO] [stderr] 30 |     let mut stdin = std::io::stdin();
[INFO] [stderr]    |         ----^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:30:9
[INFO] [stderr]    |
[INFO] [stderr] 30 |     let mut stdin = std::io::stdin();
[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]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.77s
[INFO] running `"docker" "inspect" "ca7ad85fccb6be1bc22fef83856c39d5999599595f05ad0061a1ea3ecb17a658"`
[INFO] running `"docker" "rm" "-f" "ca7ad85fccb6be1bc22fef83856c39d5999599595f05ad0061a1ea3ecb17a658"`
[INFO] [stdout] ca7ad85fccb6be1bc22fef83856c39d5999599595f05ad0061a1ea3ecb17a658