[INFO] cloning repository https://github.com/alex-kattathra-johnson/rustlings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/alex-kattathra-johnson/rustlings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falex-kattathra-johnson%2Frustlings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falex-kattathra-johnson%2Frustlings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bd5909ccba73229a521eebef79d8166b7bcdc518
[INFO] checking alex-kattathra-johnson/rustlings against c60b92c03ca8a3b101eb9d57f51e2232690638c7 for pr-164148-crater-rollup
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falex-kattathra-johnson%2Frustlings" "/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/alex-kattathra-johnson/rustlings
[INFO] finished tweaking git repo https://github.com/alex-kattathra-johnson/rustlings
[INFO] tweaked toml for git repo https://github.com/alex-kattathra-johnson/rustlings written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/alex-kattathra-johnson/rustlings on toolchain c60b92c03ca8a3b101eb9d57f51e2232690638c7
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c60b92c03ca8a3b101eb9d57f51e2232690638c7" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c60b92c03ca8a3b101eb9d57f51e2232690638c7" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c60b92c03ca8a3b101eb9d57f51e2232690638c7" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:77db811e55d90add9212f6832c23229e3de5f1c1f9905e8cb07319ea15df73ac" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8
[INFO] running `Command { std: "docker" "start" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8" "/opt/rustwide/cargo-home/bin/cargo" "+c60b92c03ca8a3b101eb9d57f51e2232690638c7" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8" "/opt/rustwide/cargo-home/bin/cargo" "+c60b92c03ca8a3b101eb9d57f51e2232690638c7" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]     Checking exercises v0.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function `trim_me` is never used
[INFO] [stdout]  --> exercises/09_strings/strings3.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn trim_me(input: &str) -> &str {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `compose_me` is never used
[INFO] [stdout]  --> exercises/09_strings/strings3.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn compose_me(input: &str) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `replace_me` is never used
[INFO] [stdout]  --> exercises/09_strings/strings3.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn replace_me(input: &str) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vec_loop` is never used
[INFO] [stdout]  --> exercises/05_vecs/vecs2.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn vec_loop(input: &[i32]) -> Vec<i32> {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vec_map_example` is never used
[INFO] [stdout]   --> exercises/05_vecs/vecs2.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn vec_map_example(input: &[i32]) -> Vec<i32> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vec_map` is never used
[INFO] [stdout]   --> exercises/05_vecs/vecs2.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn vec_map(input: &[i32]) -> Vec<i32> {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `AppendBar` is never used
[INFO] [stdout]  --> solutions/15_traits/traits2.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait AppendBar {
[INFO] [stdout]   |       ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `foo_if_fizz` is never used
[INFO] [stdout]  --> solutions/03_if/if2.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn foo_if_fizz(fizzish: &str) -> &str {
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ColorRegularStruct` is never constructed
[INFO] [stdout]  --> exercises/07_structs/structs1.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct ColorRegularStruct {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ColorTupleStruct` is never constructed
[INFO] [stdout]  --> exercises/07_structs/structs1.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct ColorTupleStruct(u8, u8, u8);
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `UnitStruct` is never constructed
[INFO] [stdout]   --> exercises/07_structs/structs1.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct UnitStruct;
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Licensed` is never used
[INFO] [stdout]  --> solutions/15_traits/traits4.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Licensed {
[INFO] [stdout]   |       ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SomeSoftware` is never constructed
[INFO] [stdout]  --> solutions/15_traits/traits4.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct SomeSoftware;
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `OtherSoftware` is never constructed
[INFO] [stdout]  --> solutions/15_traits/traits4.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct OtherSoftware;
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `compare_license_types` is never used
[INFO] [stdout]   --> solutions/15_traits/traits4.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn compare_license_types(software1: impl Licensed, software2: impl Licensed) -> bool {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Package` is never constructed
[INFO] [stdout]  --> exercises/07_structs/structs3.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Package {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `is_international`, and `get_fees` are never used
[INFO] [stdout]   --> exercises/07_structs/structs3.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 11 | impl Package {
[INFO] [stdout]    | ------------ associated items in this implementation
[INFO] [stdout] 12 |     fn new(sender_country: String, recipient_country: String, weight_in_grams: u32) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 27 |     fn is_international(&self) -> bool {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 32 |     fn get_fees(&self, cents_per_gram: u32) -> u32 {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fill_vec` is never used
[INFO] [stdout]  --> exercises/06_move_semantics/move_semantics1.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `calculate_price_of_apples` is never used
[INFO] [stdout]  --> solutions/quizzes/quiz1.rs:6:4
[INFO] [stdout]   |
[INFO] [stdout] 6 | fn calculate_price_of_apples(n_apples: u64) -> u64 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `generate_nametag_text` is never used
[INFO] [stdout]  --> exercises/13_error_handling/errors1.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn generate_nametag_text(name: String) -> Result<String, String> {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `power_of_2` is never used
[INFO] [stdout]  --> exercises/17_tests/tests2.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn power_of_2(n: u8) -> u64 {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fill_vec` is never used
[INFO] [stdout]  --> exercises/06_move_semantics/move_semantics3.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn fill_vec(mut vec: Vec<i32>) -> Vec<i32> {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Wrapper` is never constructed
[INFO] [stdout]  --> exercises/14_generics/generics2.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Wrapper<T> {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]  --> exercises/14_generics/generics2.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | impl<T> Wrapper<T> {
[INFO] [stdout]   | ------------------ associated function in this implementation
[INFO] [stdout] 9 |     fn new(value: T) -> Self {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ops::Mul`
[INFO] [stdout]  --> exercises/23_conversions/as_ref_mut.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::ops::Mul;
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `DivisionError` is never used
[INFO] [stdout]  --> solutions/18_iterators/iterators3.rs:2:6
[INFO] [stdout]   |
[INFO] [stdout] 2 | enum DivisionError {
[INFO] [stdout]   |      ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `divide` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators3.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn divide(a: i64, b: i64) -> Result<i64, DivisionError> {
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `result_with_list` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators3.rs:27:4
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn result_with_list() -> Result<Vec<i64>, DivisionError> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `list_of_results` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators3.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn list_of_results() -> Vec<Result<i64, DivisionError>> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `placeholder` is never used
[INFO] [stdout]  --> exercises/09_strings/strings4.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn placeholder() {}
[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 `Progress` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:10:6
[INFO] [stdout]    |
[INFO] [stdout] 10 | enum Progress {
[INFO] [stdout]    |      ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_for` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:16:4
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn count_for(map: &HashMap<String, Progress>, value: Progress) -> usize {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_iterator` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:26:4
[INFO] [stdout]    |
[INFO] [stdout] 26 | fn count_iterator(map: &HashMap<String, Progress>, value: Progress) -> usize {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_collection_for` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:32:4
[INFO] [stdout]    |
[INFO] [stdout] 32 | fn count_collection_for(collection: &[HashMap<String, Progress>], value: Progress) -> usize {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_collection_iterator` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn count_collection_iterator(collection: &[HashMap<String, Progress>], value: Progress) -> usize {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_collection_iterator_flat` is never used
[INFO] [stdout]   --> solutions/18_iterators/iterators5.rs:53:4
[INFO] [stdout]    |
[INFO] [stdout] 53 | fn count_collection_iterator_flat(
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Fruit` is never used
[INFO] [stdout]   --> exercises/11_hashmaps/hashmaps2.rs:14:6
[INFO] [stdout]    |
[INFO] [stdout] 14 | enum Fruit {
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fruit_basket` is never used
[INFO] [stdout]   --> exercises/11_hashmaps/hashmaps2.rs:22:4
[INFO] [stdout]    |
[INFO] [stdout] 22 | fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `details` is never used
[INFO] [stdout]   --> solutions/19_smart_pointers/rc1.rs:25:8
[INFO] [stdout]    |
[INFO] [stdout] 24 | impl Planet {
[INFO] [stdout]    | ----------- method in this implementation
[INFO] [stdout] 25 |     fn details(&self) {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Queue` is never constructed
[INFO] [stdout]  --> exercises/20_threads/threads3.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Queue {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]  --> exercises/20_threads/threads3.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | impl Queue {
[INFO] [stdout]   | ---------- associated function in this implementation
[INFO] [stdout] 9 |     fn new() -> Self {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `send_tx` is never used
[INFO] [stdout]   --> exercises/20_threads/threads3.rs:17:4
[INFO] [stdout]    |
[INFO] [stdout] 17 | fn send_tx(q: Queue, tx: mpsc::Sender<u32>) {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `AppendBar` is never used
[INFO] [stdout]  --> exercises/15_traits/traits2.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait AppendBar {
[INFO] [stdout]   |       ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: useless conversion to the same type: `&str` strings4_sol
[INFO] [stdout]   --> solutions/09_strings/strings4.rs:25:18
[INFO] [stdout]    |
[INFO] [stdout] 25 |     string_slice("nice weather".into());
[INFO] [stdout]    |                  ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this method call relies on the `impl<T> Into<T> for T` blanket implementation and type inference, which is a semver hazard as a new `impl Into<_>` that affects your type might be added in the future causing type inference errors
[INFO] [stdout]    = note: `#[deny(self_type_conversion)]` on by default
[INFO] [stdout] help: consider removing the conversion call
[INFO] [stdout]    |
[INFO] [stdout] 25 -     string_slice("nice weather".into());
[INFO] [stdout] 25 +     string_slice("nice weather");
[INFO] [stdout]    |
[INFO] [stdout] help: you can use the fully-qualified path to avoid triggering this lint
[INFO] [stdout]    |
[INFO] [stdout] 25 -     string_slice("nice weather".into());
[INFO] [stdout] 25 +     string_slice(<&str as Into<_>>::into("nice weather"));
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `exercises` (bin "strings4_sol") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: function `array_and_vec` is never used
[INFO] [stdout]  --> solutions/05_vecs/vecs1.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn array_and_vec() -> ([i32; 4], Vec<i32>) {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Licensed` is never used
[INFO] [stdout]  --> exercises/15_traits/traits4.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Licensed {
[INFO] [stdout]   |       ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SomeSoftware` is never constructed
[INFO] [stdout]  --> exercises/15_traits/traits4.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct SomeSoftware;
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `OtherSoftware` is never constructed
[INFO] [stdout]  --> exercises/15_traits/traits4.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct OtherSoftware;
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `compare_license_types` is never used
[INFO] [stdout]   --> exercises/15_traits/traits4.rs:14:4
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn compare_license_types(software1: impl Licensed, software2: impl Licensed) -> bool {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `CreationError` is never used
[INFO] [stdout]   --> solutions/13_error_handling/errors6.rs:10:6
[INFO] [stdout]    |
[INFO] [stdout] 10 | enum CreationError {
[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 `ParsePosNonzeroError` is never used
[INFO] [stdout]   --> solutions/13_error_handling/errors6.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 | enum ParsePosNonzeroError {
[INFO] [stdout]    |      ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated functions `from_creation` and `from_parse_int` are never used
[INFO] [stdout]   --> solutions/13_error_handling/errors6.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | impl ParsePosNonzeroError {
[INFO] [stdout]    | ------------------------- associated functions in this implementation
[INFO] [stdout] 23 |     fn from_creation(err: CreationError) -> Self {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 27 |     fn from_parse_int(err: ParseIntError) -> Self {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `PositiveNonzeroInteger` is never constructed
[INFO] [stdout]   --> solutions/13_error_handling/errors6.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 | struct PositiveNonzeroInteger(u64);
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated functions `new` and `parse` are never used
[INFO] [stdout]   --> solutions/13_error_handling/errors6.rs:36:8
[INFO] [stdout]    |
[INFO] [stdout] 35 | impl PositiveNonzeroInteger {
[INFO] [stdout]    | --------------------------- associated functions in this implementation
[INFO] [stdout] 36 |     fn new(value: i64) -> Result<Self, CreationError> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 44 |     fn parse(s: &str) -> Result<Self, ParsePosNonzeroError> {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `byte_counter` is never used
[INFO] [stdout]  --> solutions/23_conversions/as_ref_mut.rs:6:4
[INFO] [stdout]   |
[INFO] [stdout] 6 | fn byte_counter<T: AsRef<str>>(arg: T) -> usize {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `char_counter` is never used
[INFO] [stdout]   --> solutions/23_conversions/as_ref_mut.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn char_counter<T: AsRef<str>>(arg: T) -> usize {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `num_sq` is never used
[INFO] [stdout]   --> solutions/23_conversions/as_ref_mut.rs:16:4
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn num_sq<T: AsMut<u32>>(arg: &mut T) {
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `abs_all` is never used
[INFO] [stdout]  --> solutions/19_smart_pointers/cow1.rs:8:4
[INFO] [stdout]   |
[INFO] [stdout] 8 | fn abs_all(input: &mut Cow<[i32]>) {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8", kill_on_drop: false }`
[INFO] [stdout] b555ba336025b21a39848456d4272817a00db3cf1d630f4c66cf1155010f48c8
