[INFO] cloning repository https://github.com/T-parrish/rust_study_materials
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/T-parrish/rust_study_materials" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FT-parrish%2Frust_study_materials", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FT-parrish%2Frust_study_materials'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1be948677ac310df806a107da95fe50d0e209b71
[INFO] checking T-parrish/rust_study_materials against master#a609fb45efad59dfd459c76e50899be9f0583b5a for pr-80579
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FT-parrish%2Frust_study_materials" "/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/T-parrish/rust_study_materials on toolchain a609fb45efad59dfd459c76e50899be9f0583b5a
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a609fb45efad59dfd459c76e50899be9f0583b5a" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/T-parrish/rust_study_materials
[INFO] finished tweaking git repo https://github.com/T-parrish/rust_study_materials
[INFO] tweaked toml for git repo https://github.com/T-parrish/rust_study_materials written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/T-parrish/rust_study_materials already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a609fb45efad59dfd459c76e50899be9f0583b5a" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+a609fb45efad59dfd459c76e50899be9f0583b5a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] e55e6b03dfbcab08cee6955aaaf11e7de6b980e854fb71756cc2dbd603af4b5e
[INFO] running `Command { std: "docker" "start" "-a" "e55e6b03dfbcab08cee6955aaaf11e7de6b980e854fb71756cc2dbd603af4b5e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e55e6b03dfbcab08cee6955aaaf11e7de6b980e854fb71756cc2dbd603af4b5e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e55e6b03dfbcab08cee6955aaaf11e7de6b980e854fb71756cc2dbd603af4b5e", kill_on_drop: false }`
[INFO] [stdout] e55e6b03dfbcab08cee6955aaaf11e7de6b980e854fb71756cc2dbd603af4b5e
[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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+a609fb45efad59dfd459c76e50899be9f0583b5a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d61aa04fe5c6b6407d2a047c35aa5089a0511494e0e6566dd1f77f8818bf713b
[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" "d61aa04fe5c6b6407d2a047c35aa5089a0511494e0e6566dd1f77f8818bf713b", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking solved_problems v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/linked_list.rs:19:8
[INFO] [stdout]    |
[INFO] [stdout] 19 |     fn new() -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `push`
[INFO] [stdout]   --> src/linked_list.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fn push(&mut self, data: T) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `peek`
[INFO] [stdout]   --> src/linked_list.rs:42:8
[INFO] [stdout]    |
[INFO] [stdout] 42 |     fn peek(&self) -> Option<&T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `peek_mut`
[INFO] [stdout]   --> src/linked_list.rs:47:8
[INFO] [stdout]    |
[INFO] [stdout] 47 |     fn peek_mut(&mut self) -> Option<&mut T> {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `find`
[INFO] [stdout]   --> src/linked_list.rs:52:8
[INFO] [stdout]    |
[INFO] [stdout] 52 |     fn find(&mut self, target: T) -> Option<usize> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `into_iter`
[INFO] [stdout]    --> src/linked_list.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 |     fn into_iter(self) -> IntoIter<T> {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter`
[INFO] [stdout]    --> src/linked_list.rs:122:8
[INFO] [stdout]     |
[INFO] [stdout] 122 |     fn iter(&mut self) -> Iter<T> {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `iter_mut`
[INFO] [stdout]    --> src/linked_list.rs:147:8
[INFO] [stdout]     |
[INFO] [stdout] 147 |     fn iter_mut(&mut self) -> IterMut<T> {
[INFO] [stdout]     |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: bounds on generic parameters are not enforced in type aliases
[INFO] [stdout]   --> src/linked_list.rs:11:14
[INFO] [stdout]    |
[INFO] [stdout] 11 | type Link<T: PartialEq + Debug> = Option<Box<Node<T>>>;
[INFO] [stdout]    |              ^^^^^^^^^   ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(type_alias_bounds)]` on by default
[INFO] [stdout] help: the bound will not be checked when the type alias is used, and should be removed
[INFO] [stdout]    |
[INFO] [stdout] 11 | type Link<T> = Option<Box<Node<T>>>;
[INFO] [stdout]    |           --
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 9 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: bounds on generic parameters are not enforced in type aliases
[INFO] [stdout]   --> src/linked_list.rs:11:14
[INFO] [stdout]    |
[INFO] [stdout] 11 | type Link<T: PartialEq + Debug> = Option<Box<Node<T>>>;
[INFO] [stdout]    |              ^^^^^^^^^   ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(type_alias_bounds)]` on by default
[INFO] [stdout] help: the bound will not be checked when the type alias is used, and should be removed
[INFO] [stdout]    |
[INFO] [stdout] 11 | type Link<T> = Option<Box<Node<T>>>;
[INFO] [stdout]    |           --
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.24s
[INFO] running `Command { std: "docker" "inspect" "d61aa04fe5c6b6407d2a047c35aa5089a0511494e0e6566dd1f77f8818bf713b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d61aa04fe5c6b6407d2a047c35aa5089a0511494e0e6566dd1f77f8818bf713b", kill_on_drop: false }`
[INFO] [stdout] d61aa04fe5c6b6407d2a047c35aa5089a0511494e0e6566dd1f77f8818bf713b