[INFO] cloning repository https://github.com/daniel-j-anderson-dev/linked_lists_book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/daniel-j-anderson-dev/linked_lists_book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaniel-j-anderson-dev%2Flinked_lists_book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaniel-j-anderson-dev%2Flinked_lists_book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] df5e3098d35a90a0fabe5039f84ae0bb0c5de713
[INFO] checking daniel-j-anderson-dev/linked_lists_book against try#04ea1e1f1a12cfa912c228ca278237d92d0bb6df for pr-148477-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaniel-j-anderson-dev%2Flinked_lists_book" "/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/daniel-j-anderson-dev/linked_lists_book
[INFO] finished tweaking git repo https://github.com/daniel-j-anderson-dev/linked_lists_book
[INFO] tweaked toml for git repo https://github.com/daniel-j-anderson-dev/linked_lists_book written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/daniel-j-anderson-dev/linked_lists_book on toolchain 04ea1e1f1a12cfa912c228ca278237d92d0bb6df
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/daniel-j-anderson-dev/linked_lists_book 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" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "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
[ERROR] error running command: no output for 300 seconds
[INFO] checking daniel-j-anderson-dev/linked_lists_book against try#04ea1e1f1a12cfa912c228ca278237d92d0bb6df for pr-148477-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdaniel-j-anderson-dev%2Flinked_lists_book" "/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/daniel-j-anderson-dev/linked_lists_book
[INFO] finished tweaking git repo https://github.com/daniel-j-anderson-dev/linked_lists_book
[INFO] tweaked toml for git repo https://github.com/daniel-j-anderson-dev/linked_lists_book written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/daniel-j-anderson-dev/linked_lists_book on toolchain 04ea1e1f1a12cfa912c228ca278237d92d0bb6df
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/daniel-j-anderson-dev/linked_lists_book 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" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e08b5dc238aadfed6139fa6c6575996dbe5ba9de1920222875eceab1022d3c0f
[INFO] running `Command { std: "docker" "start" "-a" "e08b5dc238aadfed6139fa6c6575996dbe5ba9de1920222875eceab1022d3c0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e08b5dc238aadfed6139fa6c6575996dbe5ba9de1920222875eceab1022d3c0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e08b5dc238aadfed6139fa6c6575996dbe5ba9de1920222875eceab1022d3c0f", kill_on_drop: false }`
[INFO] [stdout] e08b5dc238aadfed6139fa6c6575996dbe5ba9de1920222875eceab1022d3c0f
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+04ea1e1f1a12cfa912c228ca278237d92d0bb6df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d6dd750420fa75473b6378d1675ec429617c2dc0144ada11aa6cfb6a8a2f5c92
[INFO] running `Command { std: "docker" "start" "-a" "d6dd750420fa75473b6378d1675ec429617c2dc0144ada11aa6cfb6a8a2f5c92", kill_on_drop: false }`
[INFO] [stderr]     Checking linked_lists_book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `List` is never constructed
[INFO] [stdout]  --> src/first.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub struct List<E> {
[INFO] [stdout]   |            ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Link` is never used
[INFO] [stdout]  --> src/first.rs:7:6
[INFO] [stdout]   |
[INFO] [stdout] 7 | enum Link<E> {
[INFO] [stdout]   |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Node` is never constructed
[INFO] [stdout]   --> src/first.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 | struct Node<E> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `push`, and `pop` are never used
[INFO] [stdout]   --> src/first.rs:18:18
[INFO] [stdout]    |
[INFO] [stdout] 17 | impl<E> List<E> {
[INFO] [stdout]    | --------------- associated items in this implementation
[INFO] [stdout] 18 |     pub const fn new() -> Self {
[INFO] [stdout]    |                  ^^^
[INFO] [stdout] ...
[INFO] [stdout] 22 |     pub fn push(&mut self, element: E) {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 36 |     pub fn pop(&mut self) -> Option<E> {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `List` is never constructed
[INFO] [stdout]  --> src/second.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub struct List<E> {
[INFO] [stdout]   |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `Link` is never used
[INFO] [stdout]  --> src/second.rs:7:6
[INFO] [stdout]   |
[INFO] [stdout] 7 | type Link<E> = Option<Box<Node<E>>>;
[INFO] [stdout]   |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Node` is never constructed
[INFO] [stdout]  --> src/second.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | struct Node<E> {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `push`, `pop`, `peek`, and `peek_mut` are never used
[INFO] [stdout]   --> src/second.rs:15:18
[INFO] [stdout]    |
[INFO] [stdout] 14 | impl<E> List<E> {
[INFO] [stdout]    | --------------- associated items in this implementation
[INFO] [stdout] 15 |     pub const fn new() -> Self {
[INFO] [stdout]    |                  ^^^
[INFO] [stdout] ...
[INFO] [stdout] 19 |     pub fn push(&mut self, element: E) {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 26 |     pub fn pop(&mut self) -> Option<E> {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     pub fn peek(&self) -> Option<&E> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 36 |     pub fn peek_mut(&mut self) -> Option<&mut E> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `iter` and `iter_mut` are never used
[INFO] [stdout]   --> src/second/iter.rs:12:12
[INFO] [stdout]    |
[INFO] [stdout] 11 | impl<E> List<E> {
[INFO] [stdout]    | --------------- methods in this implementation
[INFO] [stdout] 12 |     pub fn iter(&self) -> ReferenceIterator<'_, E> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 15 |     pub fn iter_mut(&mut self) -> MutableReferenceIterator<E> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ValueIterator` is never constructed
[INFO] [stdout]   --> src/second/iter.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 | pub struct ValueIterator<E>(List<E>);
[INFO] [stdout]    |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ReferenceIterator` is never constructed
[INFO] [stdout]   --> src/second/iter.rs:28:12
[INFO] [stdout]    |
[INFO] [stdout] 28 | pub struct ReferenceIterator<'a, E> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MutableReferenceIterator` is never constructed
[INFO] [stdout]   --> src/second/iter.rs:43:12
[INFO] [stdout]    |
[INFO] [stdout] 43 | pub struct MutableReferenceIterator<'a, E> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/second/iter.rs:15:21
[INFO] [stdout]    |
[INFO] [stdout] 15 |     pub fn iter_mut(&mut self) -> MutableReferenceIterator<E> {
[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] 15 |     pub fn iter_mut(&mut self) -> MutableReferenceIterator<'_, E> {
[INFO] [stdout]    |                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> src/second/iter.rs:15:21
[INFO] [stdout]    |
[INFO] [stdout] 15 |     pub fn iter_mut(&mut self) -> MutableReferenceIterator<E> {
[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] 15 |     pub fn iter_mut(&mut self) -> MutableReferenceIterator<'_, E> {
[INFO] [stdout]    |                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.21s
[INFO] running `Command { std: "docker" "inspect" "d6dd750420fa75473b6378d1675ec429617c2dc0144ada11aa6cfb6a8a2f5c92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6dd750420fa75473b6378d1675ec429617c2dc0144ada11aa6cfb6a8a2f5c92", kill_on_drop: false }`
[INFO] [stdout] d6dd750420fa75473b6378d1675ec429617c2dc0144ada11aa6cfb6a8a2f5c92
