[INFO] cloning repository https://github.com/hootisman/rust-data-structs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/hootisman/rust-data-structs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhootisman%2Frust-data-structs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhootisman%2Frust-data-structs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 58232689a22180832a0b50e3507bbb526a5e85ca
[INFO] checking hootisman/rust-data-structs against try#dd2d87b6cc31907ae305875eb6be399783dc0256 for pr-143929
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhootisman%2Frust-data-structs" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/hootisman/rust-data-structs
[INFO] finished tweaking git repo https://github.com/hootisman/rust-data-structs
[INFO] tweaked toml for git repo https://github.com/hootisman/rust-data-structs written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/hootisman/rust-data-structs on toolchain dd2d87b6cc31907ae305875eb6be399783dc0256
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+dd2d87b6cc31907ae305875eb6be399783dc0256" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/hootisman/rust-data-structs 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" "+dd2d87b6cc31907ae305875eb6be399783dc0256" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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:e8955075918b6d00525c617f7c34ee2595c70db70b3cf844dc875e4d3604499b" "/opt/rustwide/cargo-home/bin/cargo" "+dd2d87b6cc31907ae305875eb6be399783dc0256" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5ff3cf8ce5f2131c78d2b25308c697c750fd012f054187f4ad11b9ae77473f6e
[INFO] running `Command { std: "docker" "start" "-a" "5ff3cf8ce5f2131c78d2b25308c697c750fd012f054187f4ad11b9ae77473f6e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5ff3cf8ce5f2131c78d2b25308c697c750fd012f054187f4ad11b9ae77473f6e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ff3cf8ce5f2131c78d2b25308c697c750fd012f054187f4ad11b9ae77473f6e", kill_on_drop: false }`
[INFO] [stdout] 5ff3cf8ce5f2131c78d2b25308c697c750fd012f054187f4ad11b9ae77473f6e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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:e8955075918b6d00525c617f7c34ee2595c70db70b3cf844dc875e4d3604499b" "/opt/rustwide/cargo-home/bin/cargo" "+dd2d87b6cc31907ae305875eb6be399783dc0256" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a98b11b5dd35bbec71e78ebe9e976c46796f5e38e7000feb7cbc29276167fdb9
[INFO] running `Command { std: "docker" "start" "-a" "a98b11b5dd35bbec71e78ebe9e976c46796f5e38e7000feb7cbc29276167fdb9", kill_on_drop: false }`
[INFO] [stderr]     Checking rustdatastructs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `list1`
[INFO] [stdout]   --> src/main.rs:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let list1: List = List::new();
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_list1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `list1`
[INFO] [stdout]   --> src/main.rs:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let list1: List = List::new();
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_list1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:20:10
[INFO] [stdout]    |
[INFO] [stdout] 20 |     Some(Box<Node>),
[INFO] [stdout]    |     ---- ^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 20 -     Some(Box<Node>),
[INFO] [stdout] 20 +     Some(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `next` are never read
[INFO] [stdout]   --> src/main.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | struct Node {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 23 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 24 |     next: Link,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:20:10
[INFO] [stdout]    |
[INFO] [stdout] 20 |     Some(Box<Node>),
[INFO] [stdout]    |     ---- ^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 20 -     Some(Box<Node>),
[INFO] [stdout] 20 +     Some(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `next` are never read
[INFO] [stdout]   --> src/main.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 22 | struct Node {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 23 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 24 |     next: Link,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.05s
[INFO] running `Command { std: "docker" "inspect" "a98b11b5dd35bbec71e78ebe9e976c46796f5e38e7000feb7cbc29276167fdb9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a98b11b5dd35bbec71e78ebe9e976c46796f5e38e7000feb7cbc29276167fdb9", kill_on_drop: false }`
[INFO] [stdout] a98b11b5dd35bbec71e78ebe9e976c46796f5e38e7000feb7cbc29276167fdb9