Dec 17 15:08:24.419 INFO checking snoyberg/rush-crash-course-tokio-exercise-2 against master#96d1334e567237b1507cd277938e7ae2de75ff51 for pr-54252
Dec 17 15:08:24.419 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-54252/worker-6/master#96d1334e567237b1507cd277938e7ae2de75ff51:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-54252/sources/master#96d1334e567237b1507cd277938e7ae2de75ff51/gh/snoyberg/rush-crash-course-tokio-exercise-2:/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" "+96d1334e567237b1507cd277938e7ae2de75ff51-alt" "check" "--frozen" "--all" "--all-targets"`
Dec 17 15:08:24.848 INFO [stdout] d91356d59f38b14da60c69ca79b7f8424bb5b725eceaf2871691b982e0aa3282
Dec 17 15:08:24.850 INFO running `"docker" "start" "-a" "d91356d59f38b14da60c69ca79b7f8424bb5b725eceaf2871691b982e0aa3282"`
Dec 17 15:08:26.445 INFO [stderr]     Checking tokio-threadpool v0.1.9
Dec 17 15:08:27.858 INFO [stderr]     Checking tokio-fs v0.1.4
Dec 17 15:08:28.398 INFO [stderr]     Checking tokio v0.1.13
Dec 17 15:08:29.326 INFO [stderr]     Checking exercise2 v0.1.0 (/opt/crater/workdir)
Dec 17 15:08:29.796 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.50s
Dec 17 15:08:30.575 INFO running `"docker" "inspect" "d91356d59f38b14da60c69ca79b7f8424bb5b725eceaf2871691b982e0aa3282"`
Dec 17 15:08:30.868 INFO running `"docker" "rm" "-f" "d91356d59f38b14da60c69ca79b7f8424bb5b725eceaf2871691b982e0aa3282"`
Dec 17 15:08:31.164 INFO [stdout] d91356d59f38b14da60c69ca79b7f8424bb5b725eceaf2871691b982e0aa3282