[INFO] updating cached repository https://github.com/slavovojacek/8QP_rust
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d954f74f594f63fe348d514e1cdd08ecc3d3580f
[INFO] testing slavovojacek/8QP_rust against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fslavovojacek%2F8QP_rust" "work/builds/worker-2/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/slavovojacek/8QP_rust on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/slavovojacek/8QP_rust
[INFO] finished tweaking git repo https://github.com/slavovojacek/8QP_rust
[INFO] tweaked toml for git repo https://github.com/slavovojacek/8QP_rust written to work/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/slavovojacek/8QP_rust already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] d3a9366de0f3d54ac970b40c54f226a2bb8be548e92f6fd0158b28a7c152acff
[INFO] running `"docker" "start" "-a" "d3a9366de0f3d54ac970b40c54f226a2bb8be548e92f6fd0158b28a7c152acff"`
[INFO] [stderr]    Compiling eight_queen_problem v0.1.0 (/opt/rustwide/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 0.76s
[INFO] running `"docker" "inspect" "d3a9366de0f3d54ac970b40c54f226a2bb8be548e92f6fd0158b28a7c152acff"`
[INFO] running `"docker" "rm" "-f" "d3a9366de0f3d54ac970b40c54f226a2bb8be548e92f6fd0158b28a7c152acff"`
[INFO] [stdout] d3a9366de0f3d54ac970b40c54f226a2bb8be548e92f6fd0158b28a7c152acff
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 1ccd00ff2ef67338cb2422b23d2386fa32ea170580366128d757e6f9dbea365b
[INFO] running `"docker" "start" "-a" "1ccd00ff2ef67338cb2422b23d2386fa32ea170580366128d757e6f9dbea365b"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling eight_queen_problem v0.1.0 (/opt/rustwide/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 2.02s
[INFO] running `"docker" "inspect" "1ccd00ff2ef67338cb2422b23d2386fa32ea170580366128d757e6f9dbea365b"`
[INFO] running `"docker" "rm" "-f" "1ccd00ff2ef67338cb2422b23d2386fa32ea170580366128d757e6f9dbea365b"`
[INFO] [stdout] 1ccd00ff2ef67338cb2422b23d2386fa32ea170580366128d757e6f9dbea365b
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen"`
[INFO] [stdout] a4f5f40f246abe03751214d1bda907c743355bf0d2283f3e14584713c651dbca
[INFO] running `"docker" "start" "-a" "a4f5f40f246abe03751214d1bda907c743355bf0d2283f3e14584713c651dbca"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/eight_queen_problem-a7e31c26d429e0e2
[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" "a4f5f40f246abe03751214d1bda907c743355bf0d2283f3e14584713c651dbca"`
[INFO] running `"docker" "rm" "-f" "a4f5f40f246abe03751214d1bda907c743355bf0d2283f3e14584713c651dbca"`
[INFO] [stdout] a4f5f40f246abe03751214d1bda907c743355bf0d2283f3e14584713c651dbca