[INFO] cloning repository jonstites/algorithms
[INFO] running `"git" "clone" "--bare" "git://github.com/jonstites/algorithms.git" "work/cache/sources/gh/jonstites/algorithms"`
[INFO] [stderr] Cloning into bare repository 'work/cache/sources/gh/jonstites/algorithms'...
[INFO] running `"git" "clone" "work/cache/sources/gh/jonstites/algorithms" "work/ex/pr-62008/sources/master#848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1/gh/jonstites/algorithms"`
[INFO] [stderr] Cloning into 'work/ex/pr-62008/sources/master#848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1/gh/jonstites/algorithms'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/jonstites/algorithms" "work/ex/pr-62008/sources/try#8f81d0bf6baf07b92f1246696722485c4ca0b049/gh/jonstites/algorithms"`
[INFO] [stderr] Cloning into 'work/ex/pr-62008/sources/try#8f81d0bf6baf07b92f1246696722485c4ca0b049/gh/jonstites/algorithms'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 43b44b5150b0c9c35d737331583bd90d02c94b98
[INFO] sha for GitHub repo jonstites/algorithms: 43b44b5150b0c9c35d737331583bd90d02c94b98
[INFO] validating manifest of jonstites/algorithms on toolchain master#848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1
[INFO] running `"/mnt/big/ec2-user/crater/work/local/cargo-home/bin/cargo" "+848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of jonstites/algorithms on toolchain try#8f81d0bf6baf07b92f1246696722485c4ca0b049
[INFO] running `"/mnt/big/ec2-user/crater/work/local/cargo-home/bin/cargo" "+8f81d0bf6baf07b92f1246696722485c4ca0b049-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing jonstites/algorithms
[INFO] finished frobbing jonstites/algorithms
[INFO] frobbed toml for jonstites/algorithms written to work/ex/pr-62008/sources/master#848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1/gh/jonstites/algorithms/Cargo.toml
[INFO] started frobbing jonstites/algorithms
[INFO] finished frobbing jonstites/algorithms
[INFO] frobbed toml for jonstites/algorithms written to work/ex/pr-62008/sources/try#8f81d0bf6baf07b92f1246696722485c4ca0b049/gh/jonstites/algorithms/Cargo.toml
[INFO] crate jonstites/algorithms already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/ec2-user/crater/work/local/cargo-home/bin/cargo" "+848e0a23f34aaab3e4a974b031c86ef2a4e4fcc1-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/ec2-user/crater/work/local/cargo-home/bin/cargo" "+8f81d0bf6baf07b92f1246696722485c4ca0b049-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking jonstites/algorithms against try#8f81d0bf6baf07b92f1246696722485c4ca0b049 for pr-62008
[INFO] running `"docker" "create" "-v" "/mnt/big/ec2-user/crater/work/local/target-dirs/pr-62008/worker-2/try#8f81d0bf6baf07b92f1246696722485c4ca0b049:/opt/crater/target:rw,Z" "-v" "/mnt/big/ec2-user/crater/work/ex/pr-62008/sources/try#8f81d0bf6baf07b92f1246696722485c4ca0b049/gh/jonstites/algorithms:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/ec2-user/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/ec2-user/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" "+8f81d0bf6baf07b92f1246696722485c4ca0b049-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 02815e7f3c3efa740f7d1902a2f9a0acdb111c5df3320810f526042589a894ab
[INFO] running `"docker" "start" "-a" "02815e7f3c3efa740f7d1902a2f9a0acdb111c5df3320810f526042589a894ab"`
[INFO] [stderr]     Checking algorithms v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `std::iter`
[INFO] [stderr]    --> src/lib.rs:365:9
[INFO] [stderr]     |
[INFO] [stderr] 365 |     use std::iter;
[INFO] [stderr]     |         ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::iter`
[INFO] [stderr]    --> src/lib.rs:365:9
[INFO] [stderr]     |
[INFO] [stderr] 365 |     use std::iter;
[INFO] [stderr]     |         ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `head`
[INFO] [stderr]    --> src/lib.rs:272:17
[INFO] [stderr]     |
[INFO] [stderr] 272 |             let head = match self.to_head() {
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_head`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `nodes`
[INFO] [stderr]    --> src/data.rs:501:13
[INFO] [stderr]     |
[INFO] [stderr] 501 |             nodes: Vec<T>,
[INFO] [stderr]     |             ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `head`
[INFO] [stderr]    --> src/lib.rs:272:17
[INFO] [stderr]     |
[INFO] [stderr] 272 |             let head = match self.to_head() {
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_head`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `nodes`
[INFO] [stderr]    --> src/data.rs:501:13
[INFO] [stderr]     |
[INFO] [stderr] 501 |             nodes: Vec<T>,
[INFO] [stderr]     |             ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/lib.rs:347:13
[INFO] [stderr]     |
[INFO] [stderr] 347 |             graph.add_edge(a, b);
[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/lib.rs:352:13
[INFO] [stderr]     |
[INFO] [stderr] 352 |             graph.add_edge(c, d);
[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/lib.rs:353:13
[INFO] [stderr]     |
[INFO] [stderr] 353 |             graph.add_edge(d, c);
[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 1.40s
[INFO] running `"docker" "inspect" "02815e7f3c3efa740f7d1902a2f9a0acdb111c5df3320810f526042589a894ab"`
[INFO] running `"docker" "rm" "-f" "02815e7f3c3efa740f7d1902a2f9a0acdb111c5df3320810f526042589a894ab"`
[INFO] [stdout] 02815e7f3c3efa740f7d1902a2f9a0acdb111c5df3320810f526042589a894ab