[INFO] updating cached repository https://github.com/kylehz/datastruct-rs
[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] a3f3651406dca899435da60d92024842face5a92
[INFO] checking kylehz/datastruct-rs against try#ea663bba38739867a4b75ac820991b4f5d093c3b for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkylehz%2Fdatastruct-rs" "/workspace/builds/worker-3/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kylehz/datastruct-rs on toolchain ea663bba38739867a4b75ac820991b4f5d093c3b
[INFO] running `"/workspace/cargo-home/bin/cargo" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/kylehz/datastruct-rs
[INFO] finished tweaking git repo https://github.com/kylehz/datastruct-rs
[INFO] tweaked toml for git repo https://github.com/kylehz/datastruct-rs written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/kylehz/datastruct-rs already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+ea663bba38739867a4b75ac820991b4f5d093c3b" "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] cd66901c16e29a887d8ae8d1e80c2da92ddb84fee43705a4a41bac1534c2a3cf
[INFO] running `"docker" "start" "-a" "cd66901c16e29a887d8ae8d1e80c2da92ddb84fee43705a4a41bac1534c2a3cf"`
[INFO] [stderr]     Checking datastruct-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]   --> src/vec_deque.rs:26:13
[INFO] [stderr]    |
[INFO] [stderr] 26 |         for i in 0..additional {
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_i`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/linked_list.rs:40:13
[INFO] [stderr]    |
[INFO] [stderr] 40 |         let mut node = Node::new(elem);
[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/linked_list.rs:75:13
[INFO] [stderr]    |
[INFO] [stderr] 75 |         let mut node = Node::new(elem);
[INFO] [stderr]    |             ----^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `len`
[INFO] [stderr]   --> src/linked_list.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     len: usize,
[INFO] [stderr]    |     ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]   --> src/vec_deque.rs:26:13
[INFO] [stderr]    |
[INFO] [stderr] 26 |         for i in 0..additional {
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_i`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/linked_list.rs:40:13
[INFO] [stderr]    |
[INFO] [stderr] 40 |         let mut node = Node::new(elem);
[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/linked_list.rs:75:13
[INFO] [stderr]    |
[INFO] [stderr] 75 |         let mut node = Node::new(elem);
[INFO] [stderr]    |             ----^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `len`
[INFO] [stderr]   --> src/linked_list.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     len: usize,
[INFO] [stderr]    |     ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.35s
[INFO] running `"docker" "inspect" "cd66901c16e29a887d8ae8d1e80c2da92ddb84fee43705a4a41bac1534c2a3cf"`
[INFO] running `"docker" "rm" "-f" "cd66901c16e29a887d8ae8d1e80c2da92ddb84fee43705a4a41bac1534c2a3cf"`
[INFO] [stdout] cd66901c16e29a887d8ae8d1e80c2da92ddb84fee43705a4a41bac1534c2a3cf