[INFO] cloning repository https://github.com/shanlihou/rust_play
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/shanlihou/rust_play" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanlihou%2Frust_play", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanlihou%2Frust_play'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a1bfb70a5bbead0cbe7c4b7420ecd33e8c07d64e
[INFO] testing shanlihou/rust_play against 1.60.0 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanlihou%2Frust_play" "/workspace/builds/worker-27/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-27/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/shanlihou/rust_play on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/shanlihou/rust_play
[INFO] finished tweaking git repo https://github.com/shanlihou/rust_play
[INFO] tweaked toml for git repo https://github.com/shanlihou/rust_play written to /workspace/builds/worker-27/source/Cargo.toml
[INFO] crate git repo https://github.com/shanlihou/rust_play already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b3308fa9fa1a673a6deb353771007ff220b59641a9b9aac534915e073a6cec15
[INFO] running `Command { std: "docker" "start" "-a" "b3308fa9fa1a673a6deb353771007ff220b59641a9b9aac534915e073a6cec15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b3308fa9fa1a673a6deb353771007ff220b59641a9b9aac534915e073a6cec15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b3308fa9fa1a673a6deb353771007ff220b59641a9b9aac534915e073a6cec15", kill_on_drop: false }`
[INFO] [stdout] b3308fa9fa1a673a6deb353771007ff220b59641a9b9aac534915e073a6cec15
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1452cb72f402e147b1caf200008f984349f7cf8c6730573956f6f9fd5bd64b53
[INFO] running `Command { std: "docker" "start" "-a" "1452cb72f402e147b1caf200008f984349f7cf8c6730573956f6f9fd5bd64b53", kill_on_drop: false }`
[INFO] [stderr]    Compiling just_test v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::marker::Copy`
[INFO] [stdout]  --> src/question_30.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::marker::Copy;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]   --> src/question_30.rs:62:28
[INFO] [stdout]    |
[INFO] [stdout] 62 |                     if let Some(_cur) = cur_root {
[INFO] [stdout]    |                            ^^^^^^^^^^   -------- this expression has type `&Box<Node>`
[INFO] [stdout]    |                            |
[INFO] [stdout]    |                            expected struct `Box`, found enum `Option`
[INFO] [stdout]    |
[INFO] [stdout]    = note: expected struct `Box<Node>`
[INFO] [stdout]                 found enum `Option<_>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `just_test` due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "1452cb72f402e147b1caf200008f984349f7cf8c6730573956f6f9fd5bd64b53", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1452cb72f402e147b1caf200008f984349f7cf8c6730573956f6f9fd5bd64b53", kill_on_drop: false }`
[INFO] [stdout] 1452cb72f402e147b1caf200008f984349f7cf8c6730573956f6f9fd5bd64b53