[INFO] updating cached repository slavovojacek/8QP_rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/slavovojacek/8QP_rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/slavovojacek/8QP_rust" "work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/slavovojacek/8QP_rust" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/slavovojacek/8QP_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/slavovojacek/8QP_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d954f74f594f63fe348d514e1cdd08ecc3d3580f
[INFO] sha for GitHub repo slavovojacek/8QP_rust: d954f74f594f63fe348d514e1cdd08ecc3d3580f
[INFO] validating manifest of slavovojacek/8QP_rust 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 slavovojacek/8QP_rust 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 slavovojacek/8QP_rust
[INFO] finished frobbing slavovojacek/8QP_rust
[INFO] frobbed toml for slavovojacek/8QP_rust written to work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust/Cargo.toml
[INFO] started frobbing slavovojacek/8QP_rust
[INFO] finished frobbing slavovojacek/8QP_rust
[INFO] frobbed toml for slavovojacek/8QP_rust written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/slavovojacek/8QP_rust/Cargo.toml
[INFO] crate slavovojacek/8QP_rust 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] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing slavovojacek/8QP_rust 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-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust:/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] d2ec9a334e40fa6a67aceb7e48a3686771028fade0ab9fd3ad6a52dfe1e40a70
[INFO] running `"docker" "start" "-a" "d2ec9a334e40fa6a67aceb7e48a3686771028fade0ab9fd3ad6a52dfe1e40a70"`
[INFO] [stderr]    Compiling eight_queen_problem v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: value assigned to `empty_squares` is never read
[INFO] [stderr]   --> src/main.rs:20:13
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let mut empty_squares: Vec<Position> = Vec::new();
[INFO] [stderr]    |             ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r`
[INFO] [stderr]    --> src/main.rs:113:33
[INFO] [stderr]     |
[INFO] [stderr] 113 | fn fill_col(board: &mut Board, (r, c): Position) -> Result<(), Position> {
[INFO] [stderr]     |                                 ^ help: consider prefixing with an underscore: `_r`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.68s
[INFO] running `"docker" "inspect" "d2ec9a334e40fa6a67aceb7e48a3686771028fade0ab9fd3ad6a52dfe1e40a70"`
[INFO] running `"docker" "rm" "-f" "d2ec9a334e40fa6a67aceb7e48a3686771028fade0ab9fd3ad6a52dfe1e40a70"`
[INFO] [stdout] d2ec9a334e40fa6a67aceb7e48a3686771028fade0ab9fd3ad6a52dfe1e40a70
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust:/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] bef1dc7427b62007c11bd7fb2024eb1db2900621c8e2d33c82aa6017f1f913c9
[INFO] running `"docker" "start" "-a" "bef1dc7427b62007c11bd7fb2024eb1db2900621c8e2d33c82aa6017f1f913c9"`
[INFO] [stderr]    Compiling eight_queen_problem v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: value assigned to `empty_squares` is never read
[INFO] [stderr]   --> src/main.rs:20:13
[INFO] [stderr]    |
[INFO] [stderr] 20 |     let mut empty_squares: Vec<Position> = Vec::new();
[INFO] [stderr]    |             ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr]    = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r`
[INFO] [stderr]    --> src/main.rs:113:33
[INFO] [stderr]     |
[INFO] [stderr] 113 | fn fill_col(board: &mut Board, (r, c): Position) -> Result<(), Position> {
[INFO] [stderr]     |                                 ^ help: consider prefixing with an underscore: `_r`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.69s
[INFO] running `"docker" "inspect" "bef1dc7427b62007c11bd7fb2024eb1db2900621c8e2d33c82aa6017f1f913c9"`
[INFO] running `"docker" "rm" "-f" "bef1dc7427b62007c11bd7fb2024eb1db2900621c8e2d33c82aa6017f1f913c9"`
[INFO] [stdout] bef1dc7427b62007c11bd7fb2024eb1db2900621c8e2d33c82aa6017f1f913c9
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/slavovojacek/8QP_rust:/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] 59fa664e88b5693223c77e2b0426b2120185d745b6812d46a0f9d43ac0341632
[INFO] running `"docker" "start" "-a" "59fa664e88b5693223c77e2b0426b2120185d745b6812d46a0f9d43ac0341632"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/eight_queen_problem-bd7ab4cc4a522d1a
[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" "59fa664e88b5693223c77e2b0426b2120185d745b6812d46a0f9d43ac0341632"`
[INFO] running `"docker" "rm" "-f" "59fa664e88b5693223c77e2b0426b2120185d745b6812d46a0f9d43ac0341632"`
[INFO] [stdout] 59fa664e88b5693223c77e2b0426b2120185d745b6812d46a0f9d43ac0341632