[INFO] updating cached repository https://github.com/hnefatl/rust-linked-lists
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/mnt/big/crater/work/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] fc93bdcc2983f22ccbacc827da29434854e1c82f
[INFO] checking hnefatl/rust-linked-lists against master#4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb for pr-64672
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhnefatl%2Frust-linked-lists" "work/builds/worker-0/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/hnefatl/rust-linked-lists on toolchain 4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/hnefatl/rust-linked-lists
[INFO] finished tweaking git repo https://github.com/hnefatl/rust-linked-lists
[INFO] tweaked toml for git repo https://github.com/hnefatl/rust-linked-lists written to work/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/hnefatl/rust-linked-lists already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-0/source:/opt/rustwide/workdir:ro,Z" "-v" "/mnt/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "+4ff32c07da9d97e6dc315a4a5c9ffbb797cb27bb" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] c1efa2f07cf566760f47c146fb615a982e63b39f278477f4e76ce7a824746907
[INFO] running `"docker" "start" "-a" "c1efa2f07cf566760f47c146fb615a982e63b39f278477f4e76ce7a824746907"`
[INFO] [stderr]    Compiling getrandom v0.1.9
[INFO] [stderr]    Compiling strum_macros v0.15.0
[INFO] [stderr]     Checking rand_core v0.5.0
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]     Checking linked-lists v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/singlelinked.rs:15:5
[INFO] [stderr]    |
[INFO] [stderr] 15 |     pub fn new() -> SingleLinked<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `traverse_with`
[INFO] [stderr]   --> src/singlelinked.rs:21:5
[INFO] [stderr]    |
[INFO] [stderr] 21 |     fn traverse_with<F>(&mut self, f: F) where F: Fn(&mut T, &mut Node<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `traverse_with`
[INFO] [stderr]   --> src/singlelinked.rs:21:5
[INFO] [stderr]    |
[INFO] [stderr] 21 |     fn traverse_with<F>(&mut self, f: F) where F: Fn(&mut T, &mut Node<T>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 9.46s
[INFO] running `"docker" "inspect" "c1efa2f07cf566760f47c146fb615a982e63b39f278477f4e76ce7a824746907"`
[INFO] running `"docker" "rm" "-f" "c1efa2f07cf566760f47c146fb615a982e63b39f278477f4e76ce7a824746907"`
[INFO] [stdout] c1efa2f07cf566760f47c146fb615a982e63b39f278477f4e76ce7a824746907