[INFO] updating cached repository https://github.com/howeih/Day-41-Union-Find
[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] 32bc36cc71e78ad0217c3dc428395f49b9f0fe15
[INFO] checking howeih/Day-41-Union-Find against master#c9edc02e8320a9e5799d185910ece7d491f524e6 for pr-64398
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhoweih%2FDay-41-Union-Find" "work/builds/worker-5/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/howeih/Day-41-Union-Find 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/howeih/Day-41-Union-Find
[INFO] finished tweaking git repo https://github.com/howeih/Day-41-Union-Find
[INFO] tweaked toml for git repo https://github.com/howeih/Day-41-Union-Find written to work/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/howeih/Day-41-Union-Find 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-5/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-5/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] 374859b09cf23d66cb3372c179e90ee5b070aca3965a7a484cb6dce80f0ea934
[INFO] running `"docker" "start" "-a" "374859b09cf23d66cb3372c179e90ee5b070aca3965a7a484cb6dce80f0ea934"`
[INFO] [stderr]     Checking union_find v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `std::iter::Iterator`
[INFO] [stderr]  --> src/main.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::iter::Iterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter::Iterator`
[INFO] [stderr]  --> src/main.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::iter::Iterator;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.09s
[INFO] running `"docker" "inspect" "374859b09cf23d66cb3372c179e90ee5b070aca3965a7a484cb6dce80f0ea934"`
[INFO] running `"docker" "rm" "-f" "374859b09cf23d66cb3372c179e90ee5b070aca3965a7a484cb6dce80f0ea934"`
[INFO] [stdout] 374859b09cf23d66cb3372c179e90ee5b070aca3965a7a484cb6dce80f0ea934