[INFO] cloning repository https://github.com/titi31/palindrome
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/titi31/palindrome" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiti31%2Fpalindrome", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiti31%2Fpalindrome'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4227ed2e396471d0f938003084eedfb85815def2
[INFO] checking titi31/palindrome against master#a836d9b6413d9d593be6c09463ff8c4c70e56599 for pr-84037
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiti31%2Fpalindrome" "/workspace/builds/worker-10/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/titi31/palindrome 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/titi31/palindrome
[INFO] finished tweaking git repo https://github.com/titi31/palindrome
[INFO] tweaked toml for git repo https://github.com/titi31/palindrome written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate git repo https://github.com/titi31/palindrome 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] ce16cff481a2293ea8cea1669c1a480097a793388ff34814d5113de9203b870c
[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" "ce16cff481a2293ea8cea1669c1a480097a793388ff34814d5113de9203b870c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ce16cff481a2293ea8cea1669c1a480097a793388ff34814d5113de9203b870c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ce16cff481a2293ea8cea1669c1a480097a793388ff34814d5113de9203b870c", kill_on_drop: false }`
[INFO] [stdout] ce16cff481a2293ea8cea1669c1a480097a793388ff34814d5113de9203b870c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] [stdout] 44b295332e029be8707def9921bc399730da805eeb08c6f9bdf7379f437cf1de
[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" "44b295332e029be8707def9921bc399730da805eeb08c6f9bdf7379f437cf1de", kill_on_drop: false }`
[INFO] [stderr]     Checking palindrome v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut listtrie:LinkedList<u32>=LinkedList::new();
[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/main.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let mut listtrie:LinkedList<u32>=LinkedList::new();
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.46s
[INFO] running `Command { std: "docker" "inspect" "44b295332e029be8707def9921bc399730da805eeb08c6f9bdf7379f437cf1de", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "44b295332e029be8707def9921bc399730da805eeb08c6f9bdf7379f437cf1de", kill_on_drop: false }`
[INFO] [stdout] 44b295332e029be8707def9921bc399730da805eeb08c6f9bdf7379f437cf1de