[INFO] cloning repository https://github.com/bangbaoshi/skiplist-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/bangbaoshi/skiplist-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbangbaoshi%2Fskiplist-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbangbaoshi%2Fskiplist-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 85010f013b3b674a590402688b803af2aa662342
[INFO] checking bangbaoshi/skiplist-rs against master#a836d9b6413d9d593be6c09463ff8c4c70e56599 for pr-84037
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbangbaoshi%2Fskiplist-rs" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/bangbaoshi/skiplist-rs on toolchain a836d9b6413d9d593be6c09463ff8c4c70e56599
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a836d9b6413d9d593be6c09463ff8c4c70e56599" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/bangbaoshi/skiplist-rs
[INFO] finished tweaking git repo https://github.com/bangbaoshi/skiplist-rs
[INFO] tweaked toml for git repo https://github.com/bangbaoshi/skiplist-rs written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/bangbaoshi/skiplist-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a836d9b6413d9d593be6c09463ff8c4c70e56599" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a836d9b6413d9d593be6c09463ff8c4c70e56599" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6dbf1251db653a86a50aef7af21a27f381a2d4417cf4cc0da22e0d36c8ecfd20
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "6dbf1251db653a86a50aef7af21a27f381a2d4417cf4cc0da22e0d36c8ecfd20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6dbf1251db653a86a50aef7af21a27f381a2d4417cf4cc0da22e0d36c8ecfd20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6dbf1251db653a86a50aef7af21a27f381a2d4417cf4cc0da22e0d36c8ecfd20", kill_on_drop: false }`
[INFO] [stdout] 6dbf1251db653a86a50aef7af21a27f381a2d4417cf4cc0da22e0d36c8ecfd20
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a836d9b6413d9d593be6c09463ff8c4c70e56599" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 167b1a0da23c8e0eb0d4adc3b784678398bdff23112c4b062f8d71d8208e164a
[INFO] running `Command { std: "docker" "start" "-a" "167b1a0da23c8e0eb0d4adc3b784678398bdff23112c4b062f8d71d8208e164a", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.68
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking skiplist-rs v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cmp::Ordering`
[INFO] [stdout]  --> src/lib.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::cmp::Ordering;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::cmp::PartialEq`
[INFO] [stdout]  --> src/lib.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::cmp::PartialEq;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::LinkedList`
[INFO] [stdout]  --> src/lib.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::collections::LinkedList;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ops::FnMut`
[INFO] [stdout]  --> src/lib.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::ops::FnMut;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ptr::NonNull`
[INFO] [stdout]  --> src/lib.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::ptr::NonNull;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `core::fmt`
[INFO] [stdout]   --> src/lib.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use core::fmt;
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::cmp::Ordering`
[INFO] [stdout]  --> src/lib.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::cmp::Ordering;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::LinkedList`
[INFO] [stdout]  --> src/lib.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::collections::LinkedList;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ops::FnMut`
[INFO] [stdout]  --> src/lib.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::ops::FnMut;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ptr::NonNull`
[INFO] [stdout]  --> src/lib.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::ptr::NonNull;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::HashMap`
[INFO] [stdout]    --> src/lib.rs:406:9
[INFO] [stdout]     |
[INFO] [stdout] 406 |     use std::collections::HashMap;
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:33:21
[INFO] [stdout]    |
[INFO] [stdout] 33 |         if let Some(mut t) = self.find(&key) {
[INFO] [stdout]    |                     ----^
[INFO] [stdout]    |                     |
[INFO] [stdout]    |                     help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:33:21
[INFO] [stdout]    |
[INFO] [stdout] 33 |         if let Some(mut t) = self.find(&key) {
[INFO] [stdout]    |                     ----^
[INFO] [stdout]    |                     |
[INFO] [stdout]    |                     help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.10s
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "167b1a0da23c8e0eb0d4adc3b784678398bdff23112c4b062f8d71d8208e164a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "167b1a0da23c8e0eb0d4adc3b784678398bdff23112c4b062f8d71d8208e164a", kill_on_drop: false }`
[INFO] [stdout] 167b1a0da23c8e0eb0d4adc3b784678398bdff23112c4b062f8d71d8208e164a