[INFO] updating cached repository Flecheck/Sudoku
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Flecheck/Sudoku
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Flecheck/Sudoku" "work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Flecheck/Sudoku" "work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/Flecheck/Sudoku"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/Flecheck/Sudoku'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b4d750cdaf93f8ab6a4f354cec2008b75ebcf1b5
[INFO] sha for GitHub repo Flecheck/Sudoku: b4d750cdaf93f8ab6a4f354cec2008b75ebcf1b5
[INFO] validating manifest of Flecheck/Sudoku on toolchain master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of Flecheck/Sudoku on toolchain try#7fea0229842e79db1159ea58ad9a653b288efee9
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing Flecheck/Sudoku
[INFO] finished frobbing Flecheck/Sudoku
[INFO] frobbed toml for Flecheck/Sudoku written to work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku/Cargo.toml
[INFO] started frobbing Flecheck/Sudoku
[INFO] finished frobbing Flecheck/Sudoku
[INFO] frobbed toml for Flecheck/Sudoku written to work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/Flecheck/Sudoku/Cargo.toml
[INFO] crate Flecheck/Sudoku has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing Flecheck/Sudoku against master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54 for pr-57967
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-6/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku:/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" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "build" "--frozen"`
[INFO] [stdout] 0e5d312cf63d278d54938eefb3af87b266e653240e51951a11e9115fc951accf
[INFO] running `"docker" "start" "-a" "0e5d312cf63d278d54938eefb3af87b266e653240e51951a11e9115fc951accf"`
[INFO] [stderr]    Compiling indexmap v0.4.1
[INFO] [stderr]    Compiling priority-queue v0.5.1
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::time::Duration`
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 | use std::time::Duration;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::time::Instant`
[INFO] [stderr]   --> src/main.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 | use std::time::Instant;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:43:9
[INFO] [stderr]    |
[INFO] [stderr] 43 |         writeln!(stdout, "{}", res);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_must_use)] on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.27s
[INFO] running `"docker" "inspect" "0e5d312cf63d278d54938eefb3af87b266e653240e51951a11e9115fc951accf"`
[INFO] running `"docker" "rm" "-f" "0e5d312cf63d278d54938eefb3af87b266e653240e51951a11e9115fc951accf"`
[INFO] [stdout] 0e5d312cf63d278d54938eefb3af87b266e653240e51951a11e9115fc951accf
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-6/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku:/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" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "test" "--frozen" "--no-run"`
[INFO] [stdout] e34f08e8d3ac67c580a0f9f922fce12ccdbddc5616f30f67201a3a2ffefa4b95
[INFO] running `"docker" "start" "-a" "e34f08e8d3ac67c580a0f9f922fce12ccdbddc5616f30f67201a3a2ffefa4b95"`
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::time::Duration`
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 | use std::time::Duration;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::time::Instant`
[INFO] [stderr]   --> src/main.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 | use std::time::Instant;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:43:9
[INFO] [stderr]    |
[INFO] [stderr] 43 |         writeln!(stdout, "{}", res);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_must_use)] on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.05s
[INFO] running `"docker" "inspect" "e34f08e8d3ac67c580a0f9f922fce12ccdbddc5616f30f67201a3a2ffefa4b95"`
[INFO] running `"docker" "rm" "-f" "e34f08e8d3ac67c580a0f9f922fce12ccdbddc5616f30f67201a3a2ffefa4b95"`
[INFO] [stdout] e34f08e8d3ac67c580a0f9f922fce12ccdbddc5616f30f67201a3a2ffefa4b95
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-6/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/Flecheck/Sudoku:/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" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "test" "--frozen"`
[INFO] [stdout] a854ea5e5752c33086cde353882b384a77f41473b2e0ce49b4e8677841a1bec2
[INFO] running `"docker" "start" "-a" "a854ea5e5752c33086cde353882b384a77f41473b2e0ce49b4e8677841a1bec2"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/sudoku-34aed7377a45008f
[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" "a854ea5e5752c33086cde353882b384a77f41473b2e0ce49b4e8677841a1bec2"`
[INFO] running `"docker" "rm" "-f" "a854ea5e5752c33086cde353882b384a77f41473b2e0ce49b4e8677841a1bec2"`
[INFO] [stdout] a854ea5e5752c33086cde353882b384a77f41473b2e0ce49b4e8677841a1bec2