[INFO] cloning repository https://github.com/kylehz/datastruct-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kylehz/datastruct-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkylehz%2Fdatastruct-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkylehz%2Fdatastruct-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a3f3651406dca899435da60d92024842face5a92
[INFO] checking kylehz/datastruct-rs against master#9fa580b1175018b0a276b0bc68f9827a106f7260 for pr-82565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkylehz%2Fdatastruct-rs" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kylehz/datastruct-rs on toolchain 9fa580b1175018b0a276b0bc68f9827a106f7260
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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-7/source/Cargo.toml
[INFO] crate git repo https://github.com/kylehz/datastruct-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d097d32535716f0d6a09f6f06223039c81ee609ba44b33ed356f0a433596e7f0
[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" "d097d32535716f0d6a09f6f06223039c81ee609ba44b33ed356f0a433596e7f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d097d32535716f0d6a09f6f06223039c81ee609ba44b33ed356f0a433596e7f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d097d32535716f0d6a09f6f06223039c81ee609ba44b33ed356f0a433596e7f0", kill_on_drop: false }`
[INFO] [stdout] d097d32535716f0d6a09f6f06223039c81ee609ba44b33ed356f0a433596e7f0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+9fa580b1175018b0a276b0bc68f9827a106f7260" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bb3a4e2ef7ef329af1e2ea07debc4f3987eca92f703d316d21f4443312c31b6f
[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" "bb3a4e2ef7ef329af1e2ea07debc4f3987eca92f703d316d21f4443312c31b6f", kill_on_drop: false }`
[INFO] [stderr]     Checking datastruct-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/vec_deque.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |         for i in 0..additional {
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/linked_list.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |         let mut node = Node::new(elem);
[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/linked_list.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut node = Node::new(elem);
[INFO] [stdout]    |             ----^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `len`
[INFO] [stdout]   --> src/linked_list.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     len: usize,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/vec_deque.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |         for i in 0..additional {
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/linked_list.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |         let mut node = Node::new(elem);
[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/linked_list.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut node = Node::new(elem);
[INFO] [stdout]    |             ----^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `len`
[INFO] [stdout]   --> src/linked_list.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     len: usize,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.60s
[INFO] running `Command { std: "docker" "inspect" "bb3a4e2ef7ef329af1e2ea07debc4f3987eca92f703d316d21f4443312c31b6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bb3a4e2ef7ef329af1e2ea07debc4f3987eca92f703d316d21f4443312c31b6f", kill_on_drop: false }`
[INFO] [stdout] bb3a4e2ef7ef329af1e2ea07debc4f3987eca92f703d316d21f4443312c31b6f