[INFO] cloning repository https://github.com/a74946443/learn_rust
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/a74946443/learn_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fa74946443%2Flearn_rust"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fa74946443%2Flearn_rust'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] d4214616a24e50a567a83e50cca030906d5f2a9f
[INFO] checking a74946443/learn_rust against try#e4dba30b9b475d8750370c4dfb49b6541990904d for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fa74946443%2Flearn_rust" "/workspace/builds/worker-10/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/a74946443/learn_rust on toolchain e4dba30b9b475d8750370c4dfb49b6541990904d
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "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 /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate git repo https://github.com/a74946443/learn_rust already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded simple_redis v0.3.44
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=0" "-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" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 33238cb54e936e6ee1ed0cfc0a6d6d3e1e79da5bdad83b715d4f3329637bd0c5
[INFO] running `"docker" "start" "-a" "33238cb54e936e6ee1ed0cfc0a6d6d3e1e79da5bdad83b715d4f3329637bd0c5"`
[INFO] [stderr]     Checking smallvec v0.6.10
[INFO] [stderr]    Compiling redis v0.8.0
[INFO] [stderr]     Checking unicode-normalization v0.1.8
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking url v1.7.2
[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] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "33238cb54e936e6ee1ed0cfc0a6d6d3e1e79da5bdad83b715d4f3329637bd0c5"`
[INFO] running `"docker" "rm" "-f" "33238cb54e936e6ee1ed0cfc0a6d6d3e1e79da5bdad83b715d4f3329637bd0c5"`
[INFO] [stdout] 33238cb54e936e6ee1ed0cfc0a6d6d3e1e79da5bdad83b715d4f3329637bd0c5