[INFO] updating cached repository https://github.com/brinchj/rust-sudoku-fun
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/mnt/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] 849f6a4ac8d2168e7a273a5b1bbee70e6837cb2d
[INFO] checking brinchj/rust-sudoku-fun against master#c9edc02e8320a9e5799d185910ece7d491f524e6 for pr-64398
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrinchj%2Frust-sudoku-fun" "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/brinchj/rust-sudoku-fun on toolchain c9edc02e8320a9e5799d185910ece7d491f524e6-alt
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/brinchj/rust-sudoku-fun
[INFO] finished tweaking git repo https://github.com/brinchj/rust-sudoku-fun
[INFO] tweaked toml for git repo https://github.com/brinchj/rust-sudoku-fun written to work/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/brinchj/rust-sudoku-fun already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-2/source:/opt/rustwide/workdir:ro,Z" "-v" "/mnt/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/mnt/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=forbid" "-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" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] d1f47f577cc5adff17f7dc0cb21b5a8d7faec8031db7bf47bd3ff7e69611ab42
[INFO] running `"docker" "start" "-a" "d1f47f577cc5adff17f7dc0cb21b5a8d7faec8031db7bf47bd3ff7e69611ab42"`
[INFO] [stderr]     Checking backtrace v0.1.8
[INFO] [stderr]     Checking debugtrace v0.1.0
[INFO] [stderr]     Checking chomp v0.3.1
[INFO] [stderr]     Checking sudokusolver v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: the feature `iterator_step_by` has been stable since 1.28.0 and no longer requires an attribute to enable
[INFO] [stderr]  --> src/lib.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(iterator_step_by)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(stable_features)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: the feature `iterator_step_by` has been stable since 1.28.0 and no longer requires an attribute to enable
[INFO] [stderr]  --> src/lib.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(iterator_step_by)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(stable_features)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/main.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `#[macro_use]` import
[INFO] [stderr]  --> src/main.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #[macro_use]
[INFO] [stderr]   | ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: the feature `iterator_step_by` has been stable since 1.28.0 and no longer requires an attribute to enable
[INFO] [stderr]  --> src/main.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(iterator_step_by)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(stable_features)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: the feature `iterator_step_by` has been stable since 1.28.0 and no longer requires an attribute to enable
[INFO] [stderr]  --> src/main.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(iterator_step_by)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(stable_features)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.66s
[INFO] running `"docker" "inspect" "d1f47f577cc5adff17f7dc0cb21b5a8d7faec8031db7bf47bd3ff7e69611ab42"`
[INFO] running `"docker" "rm" "-f" "d1f47f577cc5adff17f7dc0cb21b5a8d7faec8031db7bf47bd3ff7e69611ab42"`
[INFO] [stdout] d1f47f577cc5adff17f7dc0cb21b5a8d7faec8031db7bf47bd3ff7e69611ab42