[INFO] cloning repository https://github.com/dionysusliu/rust-skip-list
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dionysusliu/rust-skip-list" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdionysusliu%2Frust-skip-list", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdionysusliu%2Frust-skip-list'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0eb6b7ec35fbe2f08e97b5816ba058475ec07d36
[INFO] checking dionysusliu/rust-skip-list against try#44e31dee3cf6f37b4f652572897bb0eb25c477ee for pr-139763
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdionysusliu%2Frust-skip-list" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dionysusliu/rust-skip-list on toolchain 44e31dee3cf6f37b4f652572897bb0eb25c477ee
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/dionysusliu/rust-skip-list
[INFO] finished tweaking git repo https://github.com/dionysusliu/rust-skip-list
[INFO] tweaked toml for git repo https://github.com/dionysusliu/rust-skip-list written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/dionysusliu/rust-skip-list already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] dd5776d7ca5dc23213277fbd170ab9e2905e2b16caf17d4723ffff0d1b24d123
[INFO] running `Command { std: "docker" "start" "-a" "dd5776d7ca5dc23213277fbd170ab9e2905e2b16caf17d4723ffff0d1b24d123", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dd5776d7ca5dc23213277fbd170ab9e2905e2b16caf17d4723ffff0d1b24d123", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dd5776d7ca5dc23213277fbd170ab9e2905e2b16caf17d4723ffff0d1b24d123", kill_on_drop: false }`
[INFO] [stdout] dd5776d7ca5dc23213277fbd170ab9e2905e2b16caf17d4723ffff0d1b24d123
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3aba65f975339d05a19ac242fd113be95ebaa4db6f346f12e2c7fbf20f81ae3d
[INFO] running `Command { std: "docker" "start" "-a" "3aba65f975339d05a19ac242fd113be95ebaa4db6f346f12e2c7fbf20f81ae3d", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.94
[INFO] [stderr]    Compiling unicode-ident v1.0.18
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling libc v0.2.170
[INFO] [stderr]    Compiling crossbeam-utils v0.8.21
[INFO] [stderr]     Checking byteorder v1.5.0
[INFO] [stderr]    Compiling serde v1.0.219
[INFO] [stderr]    Compiling autocfg v1.4.0
[INFO] [stderr]    Compiling serde_json v1.0.140
[INFO] [stderr]    Compiling rayon-core v1.12.1
[INFO] [stderr]     Checking either v1.15.0
[INFO] [stderr]     Checking memchr v2.7.4
[INFO] [stderr]     Checking clap_lex v0.7.4
[INFO] [stderr]     Checking plotters-backend v0.3.7
[INFO] [stderr]     Checking anstyle v1.0.10
[INFO] [stderr]     Checking regex-syntax v0.8.5
[INFO] [stderr]     Checking half v2.4.1
[INFO] [stderr]     Checking itoa v1.0.15
[INFO] [stderr]     Checking ciborium-io v0.2.2
[INFO] [stderr]     Checking ryu v1.0.20
[INFO] [stderr]     Checking itertools v0.10.5
[INFO] [stderr]     Checking same-file v1.0.6
[INFO] [stderr]     Checking cast v0.3.0
[INFO] [stderr]     Checking walkdir v2.5.0
[INFO] [stderr]     Checking anes v0.1.6
[INFO] [stderr]     Checking once_cell v1.21.1
[INFO] [stderr]     Checking ciborium-ll v0.2.2
[INFO] [stderr]     Checking oorandom v11.1.5
[INFO] [stderr]     Checking clap_builder v4.5.32
[INFO] [stderr]     Checking plotters-svg v0.3.7
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stderr]     Checking regex-automata v0.4.9
[INFO] [stderr]    Compiling quote v1.0.39
[INFO] [stderr]     Checking crossbeam-epoch v0.9.18
[INFO] [stderr]    Compiling syn v2.0.99
[INFO] [stderr]     Checking crossbeam-deque v0.8.6
[INFO] [stderr]     Checking getrandom v0.2.15
[INFO] [stderr]     Checking is-terminal v0.4.16
[INFO] [stderr]     Checking plotters v0.3.7
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking criterion-plot v0.5.0
[INFO] [stderr]     Checking clap v4.5.32
[INFO] [stderr]     Checking rayon v1.10.0
[INFO] [stderr]     Checking regex v1.11.1
[INFO] [stderr]    Compiling zerocopy-derive v0.7.35
[INFO] [stderr]    Compiling serde_derive v1.0.219
[INFO] [stderr]     Checking zerocopy v0.7.35
[INFO] [stderr]     Checking ppv-lite86 v0.2.20
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking skip_list v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `random`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::{random, Rng};
[INFO] [stdout]   |            ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Ref`
[INFO] [stdout]  --> src/lib.rs:2:17
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::{Ref, RefCell};
[INFO] [stdout]   |                 ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `lvl` is never read
[INFO] [stdout]    --> src/lib.rs:187:25
[INFO] [stdout]     |
[INFO] [stdout] 187 |                         lvl -= 1;
[INFO] [stdout]     |                         ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ciborium v0.2.2
[INFO] [stderr]     Checking tinytemplate v1.2.1
[INFO] [stderr]     Checking criterion v0.5.1
[INFO] [stdout] warning: unused import: `MAX_LEVEL`
[INFO] [stdout]  --> benches/skiplist_bench.rs:2:27
[INFO] [stdout]   |
[INFO] [stdout] 2 | use skip_list::{SkipList, MAX_LEVEL}; // adjust the name based on your crate name
[INFO] [stdout]   |                           ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bench_contains` is never used
[INFO] [stdout]   --> benches/skiplist_bench.rs:31:4
[INFO] [stdout]    |
[INFO] [stdout] 31 | fn bench_contains(c: &mut Criterion) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bench_iteration` is never used
[INFO] [stdout]   --> benches/skiplist_bench.rs:54:4
[INFO] [stdout]    |
[INFO] [stdout] 54 | fn bench_iteration(c: &mut Criterion) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bench_seek` is never used
[INFO] [stdout]   --> benches/skiplist_bench.rs:78:4
[INFO] [stdout]    |
[INFO] [stdout] 78 | fn bench_seek(c: &mut Criterion) {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `bench_compare_btreemap` is never used
[INFO] [stdout]    --> benches/skiplist_bench.rs:100:4
[INFO] [stdout]     |
[INFO] [stdout] 100 | fn bench_compare_btreemap(c: &mut Criterion) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `random`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::{random, Rng};
[INFO] [stdout]   |            ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Ref`
[INFO] [stdout]  --> src/lib.rs:2:17
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::{Ref, RefCell};
[INFO] [stdout]   |                 ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `lvl` is never read
[INFO] [stdout]    --> src/lib.rs:187:25
[INFO] [stdout]     |
[INFO] [stdout] 187 |                         lvl -= 1;
[INFO] [stdout]     |                         ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 16.96s
[INFO] running `Command { std: "docker" "inspect" "3aba65f975339d05a19ac242fd113be95ebaa4db6f346f12e2c7fbf20f81ae3d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3aba65f975339d05a19ac242fd113be95ebaa4db6f346f12e2c7fbf20f81ae3d", kill_on_drop: false }`
[INFO] [stdout] 3aba65f975339d05a19ac242fd113be95ebaa4db6f346f12e2c7fbf20f81ae3d