[INFO] updating cached repository https://github.com/bon-chi/tower_of_hanoi_in_rust
[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] 6db73d2b8c4a3dffb5c55025cbf3bd44d5188ab2
[INFO] checking bon-chi/tower_of_hanoi_in_rust against try#e4dba30b9b475d8750370c4dfb49b6541990904d for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbon-chi%2Ftower_of_hanoi_in_rust" "/workspace/builds/worker-6/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/bon-chi/tower_of_hanoi_in_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/bon-chi/tower_of_hanoi_in_rust
[INFO] finished tweaking git repo https://github.com/bon-chi/tower_of_hanoi_in_rust
[INFO] tweaked toml for git repo https://github.com/bon-chi/tower_of_hanoi_in_rust written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/bon-chi/tower_of_hanoi_in_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] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] 5848dc254ccccbd8182146904ec738dc0046cf7f6052c69f8419e812f23fcc66
[INFO] running `"docker" "start" "-a" "5848dc254ccccbd8182146904ec738dc0046cf7f6052c69f8419e812f23fcc66"`
[INFO] [stderr]     Checking tower_of_hanoi_in_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:22:9
[INFO] [stderr]    |
[INFO] [stderr] 22 |     let mut new_stream: &mut Vec<i32> = &mut hanoi_stream(n - 1, h1);
[INFO] [stderr]    |         ----^^^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:22:9
[INFO] [stderr]    |
[INFO] [stderr] 22 |     let mut new_stream: &mut Vec<i32> = &mut hanoi_stream(n - 1, h1);
[INFO] [stderr]    |         ----^^^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.66s
[INFO] running `"docker" "inspect" "5848dc254ccccbd8182146904ec738dc0046cf7f6052c69f8419e812f23fcc66"`
[INFO] running `"docker" "rm" "-f" "5848dc254ccccbd8182146904ec738dc0046cf7f6052c69f8419e812f23fcc66"`
[INFO] [stdout] 5848dc254ccccbd8182146904ec738dc0046cf7f6052c69f8419e812f23fcc66