[INFO] updating cached repository https://github.com/green4free/binary_search_tree
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] c8a7034fe1006e71dc5ca5cccc0b05d7cfda50d9
[INFO] checking green4free/binary_search_tree against master#2748a9fd93dd1a00a4521f4f16de5befbf77f6cd for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgreen4free%2Fbinary_search_tree" "/workspace/builds/worker-4/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/green4free/binary_search_tree on toolchain 2748a9fd93dd1a00a4521f4f16de5befbf77f6cd
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/green4free/binary_search_tree
[INFO] finished tweaking git repo https://github.com/green4free/binary_search_tree
[INFO] tweaked toml for git repo https://github.com/green4free/binary_search_tree written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/green4free/binary_search_tree already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "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] dc916abbb62599f099c73378b3fc0e2b62284ecb4876773461490d710d7a27d2
[INFO] running `"docker" "start" "-a" "dc916abbb62599f099c73378b3fc0e2b62284ecb4876773461490d710d7a27d2"`
[INFO] [stderr]     Checking binary_search_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/main.rs:39:9
[INFO] [stderr]    |
[INFO] [stderr] 39 |             Cons(data, ref left, ref right) => 1 + left.len() + right.len(),
[INFO] [stderr]    |                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/main.rs:46:9
[INFO] [stderr]    |
[INFO] [stderr] 46 |             Cons(data, ref left, ref right) => {
[INFO] [stderr]    |                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/main.rs:39:9
[INFO] [stderr]    |
[INFO] [stderr] 39 |             Cons(data, ref left, ref right) => 1 + left.len() + right.len(),
[INFO] [stderr]    |                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `data`
[INFO] [stderr]   --> src/main.rs:46:9
[INFO] [stderr]    |
[INFO] [stderr] 46 |             Cons(data, ref left, ref right) => {
[INFO] [stderr]    |                  ^^^^ help: consider prefixing with an underscore: `_data`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.82s
[INFO] running `"docker" "inspect" "dc916abbb62599f099c73378b3fc0e2b62284ecb4876773461490d710d7a27d2"`
[INFO] running `"docker" "rm" "-f" "dc916abbb62599f099c73378b3fc0e2b62284ecb4876773461490d710d7a27d2"`
[INFO] [stdout] dc916abbb62599f099c73378b3fc0e2b62284ecb4876773461490d710d7a27d2