[INFO] cloning repository https://github.com/SeokminHong/too-many-lists
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/SeokminHong/too-many-lists" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSeokminHong%2Ftoo-many-lists", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSeokminHong%2Ftoo-many-lists'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1cc9327d4484d31746558ea2a0ed64ef38ef13a3
[INFO] checking SeokminHong/too-many-lists against try#0611f7de057c584b8771102fde7aed6c70c71d3b for pr-146440
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSeokminHong%2Ftoo-many-lists" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/SeokminHong/too-many-lists
[INFO] finished tweaking git repo https://github.com/SeokminHong/too-many-lists
[INFO] tweaked toml for git repo https://github.com/SeokminHong/too-many-lists written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/SeokminHong/too-many-lists on toolchain 0611f7de057c584b8771102fde7aed6c70c71d3b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/SeokminHong/too-many-lists 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" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 44ce74035299c26942f4f06478a794fb9bb3dbceb17f4b3ca3167be634504f3f
[INFO] running `Command { std: "docker" "start" "-a" "44ce74035299c26942f4f06478a794fb9bb3dbceb17f4b3ca3167be634504f3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "44ce74035299c26942f4f06478a794fb9bb3dbceb17f4b3ca3167be634504f3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "44ce74035299c26942f4f06478a794fb9bb3dbceb17f4b3ca3167be634504f3f", kill_on_drop: false }`
[INFO] [stdout] 44ce74035299c26942f4f06478a794fb9bb3dbceb17f4b3ca3167be634504f3f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9d690b9c5a7b3348221c7b282957439983b9c173706d5cad38aca0a364959356
[INFO] running `Command { std: "docker" "start" "-a" "9d690b9c5a7b3348221c7b282957439983b9c173706d5cad38aca0a364959356", kill_on_drop: false }`
[INFO] [stderr]     Checking too-many-lists v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: struct `IntoIter` is never constructed
[INFO] [stdout]  --> src/second.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub struct IntoIter<T>(List<T>);
[INFO] [stdout]   |            ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `pub` struct has private fields, no public constructor, and is not otherwise reachable through the external API, so consider providing a public constructor or removing it
[INFO] [stdout]   = note: `#[deny(unused_unconstructable_pub_struct)]` (part of `#[deny(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/second.rs:1:24
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub struct IntoIter<T>(List<T>);
[INFO] [stdout]   |            --------    ^^^^^^^
[INFO] [stdout]   |            |
[INFO] [stdout]   |            field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/fourth.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     pub fn peek_front(&self) -> Option<Ref<T>> {
[INFO] [stdout]    |                       ^^^^^            ^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                       |
[INFO] [stdout]    |                       the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 65 |     pub fn peek_front(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]    |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: struct `IntoIter` is never constructed
[INFO] [stdout]  --> src/second.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub struct IntoIter<T>(List<T>);
[INFO] [stdout]   |            ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: this `pub` struct has private fields, no public constructor, and is not otherwise reachable through the external API, so consider providing a public constructor or removing it
[INFO] [stdout]   = note: `#[deny(unused_unconstructable_pub_struct)]` (part of `#[deny(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/second.rs:1:24
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub struct IntoIter<T>(List<T>);
[INFO] [stdout]   |            --------    ^^^^^^^
[INFO] [stdout]   |            |
[INFO] [stdout]   |            field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `too-many-lists` (lib test) due to 1 previous error; 2 warnings emitted
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/fourth.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     pub fn peek_front(&self) -> Option<Ref<T>> {
[INFO] [stdout]    |                       ^^^^^            ^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                       |
[INFO] [stdout]    |                       the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 65 |     pub fn peek_front(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]    |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `too-many-lists` (lib) due to 1 previous error; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "9d690b9c5a7b3348221c7b282957439983b9c173706d5cad38aca0a364959356", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9d690b9c5a7b3348221c7b282957439983b9c173706d5cad38aca0a364959356", kill_on_drop: false }`
[INFO] [stdout] 9d690b9c5a7b3348221c7b282957439983b9c173706d5cad38aca0a364959356
