[INFO] updating cached repository https://github.com/IanWhitney/rusty_twins
[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] d715a848839745ee8b56274b90a5c878d74680d4
[INFO] checking IanWhitney/rusty_twins against master#c9edc02e8320a9e5799d185910ece7d491f524e6 for pr-64398
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2FIanWhitney%2Frusty_twins" "work/builds/worker-3/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/IanWhitney/rusty_twins 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/IanWhitney/rusty_twins
[INFO] finished tweaking git repo https://github.com/IanWhitney/rusty_twins
[INFO] tweaked toml for git repo https://github.com/IanWhitney/rusty_twins written to work/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/IanWhitney/rusty_twins 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] [stderr] error: the lock file /mnt/big/crater/work/builds/worker-3/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+c9edc02e8320a9e5799d185910ece7d491f524e6-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[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-3/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-3/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] 3a2b09e4eb4c4033b27bd962b0b9c6cea5183747932508a4c51197e977a92fb2
[INFO] running `"docker" "start" "-a" "3a2b09e4eb4c4033b27bd962b0b9c6cea5183747932508a4c51197e977a92fb2"`
[INFO] [stderr]     Checking csv v0.14.7
[INFO] [stderr]     Checking rusty_twins v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `rustc_serialize::Decodable`
[INFO] [stderr]  --> src/game.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use rustc_serialize::Decodable;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:69:13
[INFO] [stderr]    |
[INFO] [stderr] 69 |             wtr.write(vec!["id", "opponent", "date", "attendee_id"].into_iter());
[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] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:89:5
[INFO] [stderr]    |
[INFO] [stderr] 89 |     fs::copy("./data/ngames.csv", "./data/games.csv");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:90:5
[INFO] [stderr]    |
[INFO] [stderr] 90 |     fs::remove_file("./data/ngames.csv");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `rustc_serialize::Decodable`
[INFO] [stderr]  --> src/game.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use rustc_serialize::Decodable;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:69:13
[INFO] [stderr]    |
[INFO] [stderr] 69 |             wtr.write(vec!["id", "opponent", "date", "attendee_id"].into_iter());
[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] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:89:5
[INFO] [stderr]    |
[INFO] [stderr] 89 |     fs::copy("./data/ngames.csv", "./data/games.csv");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:90:5
[INFO] [stderr]    |
[INFO] [stderr] 90 |     fs::remove_file("./data/ngames.csv");
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.98s
[INFO] running `"docker" "inspect" "3a2b09e4eb4c4033b27bd962b0b9c6cea5183747932508a4c51197e977a92fb2"`
[INFO] running `"docker" "rm" "-f" "3a2b09e4eb4c4033b27bd962b0b9c6cea5183747932508a4c51197e977a92fb2"`
[INFO] [stdout] 3a2b09e4eb4c4033b27bd962b0b9c6cea5183747932508a4c51197e977a92fb2