[INFO] updating cached repository https://github.com/a74946443/learn_rust
[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] [stderr] From https://github.com/a74946443/learn_rust
[INFO] [stderr]    6f43739..5b88aab  master     -> master
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 5b88aabe91a7638056c6b80642b641e10911a8c8
[INFO] checking a74946443/learn_rust against try#00e4530a79c42b21a6ca2ac1edb597c90d21f89f for pr-64672
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fa74946443%2Flearn_rust" "work/builds/worker-4/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/a74946443/learn_rust on toolchain 00e4530a79c42b21a6ca2ac1edb597c90d21f89f
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+00e4530a79c42b21a6ca2ac1edb597c90d21f89f" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/a74946443/learn_rust
[INFO] finished tweaking git repo https://github.com/a74946443/learn_rust
[INFO] tweaked toml for git repo https://github.com/a74946443/learn_rust written to work/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/a74946443/learn_rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+00e4530a79c42b21a6ca2ac1edb597c90d21f89f" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-4/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" "+00e4530a79c42b21a6ca2ac1edb597c90d21f89f" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 134b5aac917bafba9e899648701b2cd9ea4200d3c95463c4f540552c6200ec52
[INFO] running `"docker" "start" "-a" "134b5aac917bafba9e899648701b2cd9ea4200d3c95463c4f540552c6200ec52"`
[INFO] [stderr]     Checking simple_redis v0.3.44
[INFO] [stderr]     Checking learn_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0432]: unresolved import `learn_rust::exercise::length_of_longest_substring::substring`
[INFO] [stderr]   --> tests/exercise.rs:16:9
[INFO] [stderr]    |
[INFO] [stderr] 16 |     use learn_rust::exercise::length_of_longest_substring::substring;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no `substring` in `exercise::length_of_longest_substring`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0432`.
[INFO] [stderr] error: could not compile `learn_rust`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "134b5aac917bafba9e899648701b2cd9ea4200d3c95463c4f540552c6200ec52"`
[INFO] running `"docker" "rm" "-f" "134b5aac917bafba9e899648701b2cd9ea4200d3c95463c4f540552c6200ec52"`
[INFO] [stdout] 134b5aac917bafba9e899648701b2cd9ea4200d3c95463c4f540552c6200ec52