[INFO] updating cached repository sebm/checkers
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/sebm/checkers
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/sebm/checkers" "work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/sebm/checkers" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sebm/checkers"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sebm/checkers'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 07cce72a883f38ab9297467b91354fdcaacf8298
[INFO] sha for GitHub repo sebm/checkers: 07cce72a883f38ab9297467b91354fdcaacf8298
[INFO] validating manifest of sebm/checkers on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of sebm/checkers on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing sebm/checkers
[INFO] finished frobbing sebm/checkers
[INFO] frobbed toml for sebm/checkers written to work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers/Cargo.toml
[INFO] started frobbing sebm/checkers
[INFO] finished frobbing sebm/checkers
[INFO] frobbed toml for sebm/checkers written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/sebm/checkers/Cargo.toml
[INFO] crate sebm/checkers already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing sebm/checkers against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers:/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=warn" "-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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 34c777ddfbb4539e734895ff1a9d15d3dfa805a59105ffe3b6cdc2d395809bf7
[INFO] running `"docker" "start" "-a" "34c777ddfbb4539e734895ff1a9d15d3dfa805a59105ffe3b6cdc2d395809bf7"`
[INFO] [stderr]    Compiling checkers v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `initial_board`
[INFO] [stderr]  --> src/main.rs:4:26
[INFO] [stderr]   |
[INFO] [stderr] 4 | use board::{BoardSquare, initial_board, draw_board};
[INFO] [stderr]   |                          ^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `initial_board`
[INFO] [stderr]   --> src/board.rs:26:1
[INFO] [stderr]    |
[INFO] [stderr] 26 | pub fn initial_board() -> [[BoardSquare; 8]; 8] {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.35s
[INFO] running `"docker" "inspect" "34c777ddfbb4539e734895ff1a9d15d3dfa805a59105ffe3b6cdc2d395809bf7"`
[INFO] running `"docker" "rm" "-f" "34c777ddfbb4539e734895ff1a9d15d3dfa805a59105ffe3b6cdc2d395809bf7"`
[INFO] [stdout] 34c777ddfbb4539e734895ff1a9d15d3dfa805a59105ffe3b6cdc2d395809bf7
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers:/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=warn" "-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" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 417d17a7c4ebf77fbce340a95d52868d77890f9a2432da2423b4df7449c7ccee
[INFO] running `"docker" "start" "-a" "417d17a7c4ebf77fbce340a95d52868d77890f9a2432da2423b4df7449c7ccee"`
[INFO] [stderr]    Compiling checkers v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `initial_board`
[INFO] [stderr]  --> src/main.rs:4:26
[INFO] [stderr]   |
[INFO] [stderr] 4 | use board::{BoardSquare, initial_board, draw_board};
[INFO] [stderr]   |                          ^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `initial_board`
[INFO] [stderr]   --> src/board.rs:26:1
[INFO] [stderr]    |
[INFO] [stderr] 26 | pub fn initial_board() -> [[BoardSquare; 8]; 8] {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.83s
[INFO] running `"docker" "inspect" "417d17a7c4ebf77fbce340a95d52868d77890f9a2432da2423b4df7449c7ccee"`
[INFO] running `"docker" "rm" "-f" "417d17a7c4ebf77fbce340a95d52868d77890f9a2432da2423b4df7449c7ccee"`
[INFO] [stdout] 417d17a7c4ebf77fbce340a95d52868d77890f9a2432da2423b4df7449c7ccee
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/sebm/checkers:/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=warn" "-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" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] 8f0012e5fe630a202eabbf4455dbbe90115edffc6d593be25812bbbc6be91a94
[INFO] running `"docker" "start" "-a" "8f0012e5fe630a202eabbf4455dbbe90115edffc6d593be25812bbbc6be91a94"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/checkers-5e6b5c1f936a71b6
[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" "8f0012e5fe630a202eabbf4455dbbe90115edffc6d593be25812bbbc6be91a94"`
[INFO] running `"docker" "rm" "-f" "8f0012e5fe630a202eabbf4455dbbe90115edffc6d593be25812bbbc6be91a94"`
[INFO] [stdout] 8f0012e5fe630a202eabbf4455dbbe90115edffc6d593be25812bbbc6be91a94