[INFO] updating cached repository howeih/Day-41-Union-Find
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/howeih/Day-41-Union-Find
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/howeih/Day-41-Union-Find" "work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/howeih/Day-41-Union-Find"`
[INFO] [stderr] Cloning into 'work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/howeih/Day-41-Union-Find'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/howeih/Day-41-Union-Find" "work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/howeih/Day-41-Union-Find"`
[INFO] [stderr] Cloning into 'work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/howeih/Day-41-Union-Find'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 32bc36cc71e78ad0217c3dc428395f49b9f0fe15
[INFO] sha for GitHub repo howeih/Day-41-Union-Find: 32bc36cc71e78ad0217c3dc428395f49b9f0fe15
[INFO] validating manifest of howeih/Day-41-Union-Find on toolchain master#452087b4bf18cece2d52d7cd8c9147195e5404bf
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of howeih/Day-41-Union-Find on toolchain try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing howeih/Day-41-Union-Find
[INFO] finished frobbing howeih/Day-41-Union-Find
[INFO] frobbed toml for howeih/Day-41-Union-Find written to work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/howeih/Day-41-Union-Find/Cargo.toml
[INFO] started frobbing howeih/Day-41-Union-Find
[INFO] finished frobbing howeih/Day-41-Union-Find
[INFO] frobbed toml for howeih/Day-41-Union-Find written to work/ex/pr-63247/sources/try#757dacae0a9f1b46b3ab58a1f1232332e8fc7dab/gh/howeih/Day-41-Union-Find/Cargo.toml
[INFO] crate howeih/Day-41-Union-Find already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+757dacae0a9f1b46b3ab58a1f1232332e8fc7dab-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking howeih/Day-41-Union-Find against master#452087b4bf18cece2d52d7cd8c9147195e5404bf for pr-63247
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63247/worker-0/master#452087b4bf18cece2d52d7cd8c9147195e5404bf:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63247/sources/master#452087b4bf18cece2d52d7cd8c9147195e5404bf/gh/howeih/Day-41-Union-Find:/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" "+452087b4bf18cece2d52d7cd8c9147195e5404bf-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 0494fc863e5bc2e63cd9e6860c11f2ad289ca291ce20f35f363570fb0be45bd4
[INFO] running `"docker" "start" "-a" "0494fc863e5bc2e63cd9e6860c11f2ad289ca291ce20f35f363570fb0be45bd4"`
[INFO] [stderr]     Checking union_find v0.1.0 (/opt/crater/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 0.26s
[INFO] running `"docker" "inspect" "0494fc863e5bc2e63cd9e6860c11f2ad289ca291ce20f35f363570fb0be45bd4"`
[INFO] running `"docker" "rm" "-f" "0494fc863e5bc2e63cd9e6860c11f2ad289ca291ce20f35f363570fb0be45bd4"`
[INFO] [stdout] 0494fc863e5bc2e63cd9e6860c11f2ad289ca291ce20f35f363570fb0be45bd4