[INFO] updating cached repository https://github.com/Razakhel/rs-ds
[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] 7fad62cad817e09dbf5244be8a21479d641ec05a
[INFO] checking Razakhel/rs-ds against try#1a608893c03d7722effeb0058e82770bd36b4b3c for pr-66504-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FRazakhel%2Frs-ds" "/workspace/builds/worker-0/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Razakhel/rs-ds on toolchain 1a608893c03d7722effeb0058e82770bd36b4b3c
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/Razakhel/rs-ds
[INFO] finished tweaking git repo https://github.com/Razakhel/rs-ds
[INFO] tweaked toml for git repo https://github.com/Razakhel/rs-ds written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/Razakhel/rs-ds already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "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] 18db026f2ab2c0f431ea7eae2a1f531ea15507187a47aa7201d56bc2f3d3dafd
[INFO] running `"docker" "start" "-a" "18db026f2ab2c0f431ea7eae2a1f531ea15507187a47aa7201d56bc2f3d3dafd"`
[INFO] [stderr]     Checking rs-ds v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: method is never used: `peek`
[INFO] [stderr]   --> src/linked_list.rs:38:3
[INFO] [stderr]    |
[INFO] [stderr] 38 |   pub fn peek(&self) -> Option<&T> {
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `peek_mut`
[INFO] [stderr]   --> src/linked_list.rs:44:3
[INFO] [stderr]    |
[INFO] [stderr] 44 |   pub fn peek_mut(&mut self) -> Option<&mut T> {
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `into_iter`
[INFO] [stderr]   --> src/linked_list.rs:50:3
[INFO] [stderr]    |
[INFO] [stderr] 50 |   pub fn into_iter(self) -> IntoIter<T> {
[INFO] [stderr]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.34s
[INFO] running `"docker" "inspect" "18db026f2ab2c0f431ea7eae2a1f531ea15507187a47aa7201d56bc2f3d3dafd"`
[INFO] running `"docker" "rm" "-f" "18db026f2ab2c0f431ea7eae2a1f531ea15507187a47aa7201d56bc2f3d3dafd"`
[INFO] [stdout] 18db026f2ab2c0f431ea7eae2a1f531ea15507187a47aa7201d56bc2f3d3dafd