[INFO] updating cached repository MainShayne233/concurrency_demo
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/MainShayne233/concurrency_demo
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/MainShayne233/concurrency_demo" "work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/gh/MainShayne233/concurrency_demo"`
[INFO] [stderr] Cloning into 'work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/gh/MainShayne233/concurrency_demo'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/MainShayne233/concurrency_demo" "work/ex/pr-58948/sources/try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b/gh/MainShayne233/concurrency_demo"`
[INFO] [stderr] Cloning into 'work/ex/pr-58948/sources/try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b/gh/MainShayne233/concurrency_demo'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 689590c7b95a3f35c83266973d5eac10ffd04d77
[INFO] sha for GitHub repo MainShayne233/concurrency_demo: 689590c7b95a3f35c83266973d5eac10ffd04d77
[INFO] validating manifest of MainShayne233/concurrency_demo on toolchain master#0f88167f89fffe321590c5148f21b7d51d44388d
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of MainShayne233/concurrency_demo on toolchain try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing MainShayne233/concurrency_demo
[INFO] finished frobbing MainShayne233/concurrency_demo
[INFO] frobbed toml for MainShayne233/concurrency_demo written to work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/gh/MainShayne233/concurrency_demo/Cargo.toml
[INFO] started frobbing MainShayne233/concurrency_demo
[INFO] finished frobbing MainShayne233/concurrency_demo
[INFO] frobbed toml for MainShayne233/concurrency_demo written to work/ex/pr-58948/sources/try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b/gh/MainShayne233/concurrency_demo/Cargo.toml
[INFO] crate MainShayne233/concurrency_demo already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking MainShayne233/concurrency_demo against master#0f88167f89fffe321590c5148f21b7d51d44388d for pr-58948
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58948/worker-3/master#0f88167f89fffe321590c5148f21b7d51d44388d:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/gh/MainShayne233/concurrency_demo:/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" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 57f7d54440334083bb46da8f276b29aaa2aacc76dac9e1d0d4f2ddd00fd9c18e
[INFO] running `"docker" "start" "-a" "57f7d54440334083bb46da8f276b29aaa2aacc76dac9e1d0d4f2ddd00fd9c18e"`
[INFO] [stderr]     Checking concurrency_demo v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: field is never used: `workers`
[INFO] [stderr]  --> src/lib.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     workers: Vec<Worker>,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `id`
[INFO] [stderr]   --> src/lib.rs:49:5
[INFO] [stderr]    |
[INFO] [stderr] 49 |     id: usize,
[INFO] [stderr]    |     ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `thread`
[INFO] [stderr]   --> src/lib.rs:50:5
[INFO] [stderr]    |
[INFO] [stderr] 50 |     thread: thread::JoinHandle<()>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `workers`
[INFO] [stderr]  --> src/lib.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     workers: Vec<Worker>,
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `id`
[INFO] [stderr]   --> src/lib.rs:49:5
[INFO] [stderr]    |
[INFO] [stderr] 49 |     id: usize,
[INFO] [stderr]    |     ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `thread`
[INFO] [stderr]   --> src/lib.rs:50:5
[INFO] [stderr]    |
[INFO] [stderr] 50 |     thread: thread::JoinHandle<()>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.47s
[INFO] running `"docker" "inspect" "57f7d54440334083bb46da8f276b29aaa2aacc76dac9e1d0d4f2ddd00fd9c18e"`
[INFO] running `"docker" "rm" "-f" "57f7d54440334083bb46da8f276b29aaa2aacc76dac9e1d0d4f2ddd00fd9c18e"`
[INFO] [stdout] 57f7d54440334083bb46da8f276b29aaa2aacc76dac9e1d0d4f2ddd00fd9c18e