[INFO] cloning repository https://github.com/ParkinWu/search_tree
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ParkinWu/search_tree" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FParkinWu%2Fsearch_tree"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FParkinWu%2Fsearch_tree'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 1150f31d3a8e45ad85e0cf6389803ddb6d371521
[INFO] checking ParkinWu/search_tree against master#2748a9fd93dd1a00a4521f4f16de5befbf77f6cd for pr-62262-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FParkinWu%2Fsearch_tree" "/workspace/builds/worker-11/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-11/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ParkinWu/search_tree on toolchain 2748a9fd93dd1a00a4521f4f16de5befbf77f6cd
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/ParkinWu/search_tree
[INFO] finished tweaking git repo https://github.com/ParkinWu/search_tree
[INFO] tweaked toml for git repo https://github.com/ParkinWu/search_tree written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate git repo https://github.com/ParkinWu/search_tree already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] error: the lock file /workspace/builds/worker-11/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "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] 785d7cac7cbd2ee69a3962a687bf1bf4c03e9591515c9f2c51a7f05771531245
[INFO] running `"docker" "start" "-a" "785d7cac7cbd2ee69a3962a687bf1bf4c03e9591515c9f2c51a7f05771531245"`
[INFO] [stderr]     Checking binary_tree v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `Formatter`
[INFO] [stderr]  --> src/main.rs:4:24
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::fmt::{ Debug, Formatter};
[INFO] [stderr]   |                        ^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `take_next`
[INFO] [stderr]   --> src/main.rs:58:5
[INFO] [stderr]    |
[INFO] [stderr] 58 |     fn take_next(&mut self) -> Option<Box<Self>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `pop_back`
[INFO] [stderr]   --> src/main.rs:90:5
[INFO] [stderr]    |
[INFO] [stderr] 90 |     fn pop_back(&mut self) -> Option<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push_front`
[INFO] [stderr]    --> src/main.rs:103:5
[INFO] [stderr]     |
[INFO] [stderr] 103 |     fn push_front(&mut self, elem: T) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `pop_front`
[INFO] [stderr]    --> src/main.rs:113:5
[INFO] [stderr]     |
[INFO] [stderr] 113 |     fn pop_front(&mut self) -> Option<T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter`
[INFO] [stderr]    --> src/main.rs:127:5
[INFO] [stderr]     |
[INFO] [stderr] 127 |     fn iter(&self) -> Iter<T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `tail`
[INFO] [stderr]    --> src/main.rs:161:5
[INFO] [stderr]     |
[INFO] [stderr] 161 |     tail: &'a Raw<T>,
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Formatter`
[INFO] [stderr]  --> src/main.rs:4:24
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::fmt::{ Debug, Formatter};
[INFO] [stderr]   |                        ^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter`
[INFO] [stderr]    --> src/main.rs:127:5
[INFO] [stderr]     |
[INFO] [stderr] 127 |     fn iter(&self) -> Iter<T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `tail`
[INFO] [stderr]    --> src/main.rs:161:5
[INFO] [stderr]     |
[INFO] [stderr] 161 |     tail: &'a Raw<T>,
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.38s
[INFO] running `"docker" "inspect" "785d7cac7cbd2ee69a3962a687bf1bf4c03e9591515c9f2c51a7f05771531245"`
[INFO] running `"docker" "rm" "-f" "785d7cac7cbd2ee69a3962a687bf1bf4c03e9591515c9f2c51a7f05771531245"`
[INFO] [stdout] 785d7cac7cbd2ee69a3962a687bf1bf4c03e9591515c9f2c51a7f05771531245