[INFO] cloning repository https://github.com/kotamat/rust_tutorial
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kotamat/rust_tutorial" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkotamat%2Frust_tutorial", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkotamat%2Frust_tutorial'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ac89668ec9338185ffb45e145974189fcddae5d7
[INFO] checking kotamat/rust_tutorial against try#3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkotamat%2Frust_tutorial" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kotamat/rust_tutorial on toolchain 3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/kotamat/rust_tutorial
[INFO] finished tweaking git repo https://github.com/kotamat/rust_tutorial
[INFO] tweaked toml for git repo https://github.com/kotamat/rust_tutorial written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/kotamat/rust_tutorial already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "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] c9ee0a6200b07ddd84ef65daf969b9b00fa18088c60bd1a4ac106afdfb162f50
[INFO] running `Command { std: "docker" "start" "-a" "c9ee0a6200b07ddd84ef65daf969b9b00fa18088c60bd1a4ac106afdfb162f50", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c9ee0a6200b07ddd84ef65daf969b9b00fa18088c60bd1a4ac106afdfb162f50", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9ee0a6200b07ddd84ef65daf969b9b00fa18088c60bd1a4ac106afdfb162f50", kill_on_drop: false }`
[INFO] [stdout] c9ee0a6200b07ddd84ef65daf969b9b00fa18088c60bd1a4ac106afdfb162f50
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+3e59a8c2f14152ccc92a6c079f592dc2dc6fa93f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 459c0005cf720eccd9fe5c0ae4fad43ff883e5c7d3d4e0554186d7866f6c88a5
[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" "459c0005cf720eccd9fe5c0ae4fad43ff883e5c7d3d4e0554186d7866f6c88a5", kill_on_drop: false }`
[INFO] [stderr]     Checking tests v0.1.0 (/opt/rustwide/workdir/tests)
[INFO] [stderr]     Checking restaurant v0.1.0 (/opt/rustwide/workdir/restaurant)
[INFO] [stderr]     Checking collections v0.1.0 (/opt/rustwide/workdir/collections)
[INFO] [stderr]     Checking functional_features v0.1.0 (/opt/rustwide/workdir/functional_features)
[INFO] [stderr]     Checking structs v0.1.0 (/opt/rustwide/workdir/structs)
[INFO] [stderr]     Checking rust_tutorial v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking function v0.1.0 (/opt/rustwide/workdir/function)
[INFO] [stderr]     Checking ownership v0.1.0 (/opt/rustwide/workdir/ownership)
[INFO] [stderr]     Checking enums v0.1.0 (/opt/rustwide/workdir/enums)
[INFO] [stderr]     Checking variable v0.1.0 (/opt/rustwide/workdir/variable)
[INFO] [stdout] warning: unused import: `std::collections::hash_map::RandomState`
[INFO] [stdout]  --> functional_features/src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::collections::hash_map::RandomState;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order1`
[INFO] [stdout]   --> restaurant/src/lib.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let order1 = Soup;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order2`
[INFO] [stdout]   --> restaurant/src/lib.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let order2 = Salad;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]  --> restaurant/src/lib.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn serve_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fix_incorrect_order`
[INFO] [stdout]   --> restaurant/src/lib.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn fix_incorrect_order() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cook_order`
[INFO] [stdout]   --> restaurant/src/lib.rs:15:8
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn cook_order() {}
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> restaurant/src/lib.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |         seasonal_fruit: String,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `user2`
[INFO] [stdout]   --> structs/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let user2 = User {
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_user2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `black`
[INFO] [stdout]   --> structs/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let black = Color(0, 0, 0);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_black`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `origin`
[INFO] [stdout]   --> structs/src/main.rs:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let origin = Point(0, 0, 0);
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_origin`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `email`
[INFO] [stdout]  --> structs/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     email: String,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `sign_in_count`
[INFO] [stdout]  --> structs/src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     sign_in_count: u64,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `active`
[INFO] [stdout]  --> structs/src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     active: bool,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking generics v0.1.0 (/opt/rustwide/workdir/generics)
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> tests/src/lib.rs:63:17
[INFO] [stdout]    |
[INFO] [stdout] 63 | pub fn greeting(name: &str) -> String {
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order1`
[INFO] [stdout]   --> restaurant/src/lib.rs:43:9
[INFO] [stdout]    |
[INFO] [stdout] 43 |     let order1 = Soup;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `order2`
[INFO] [stdout]   --> restaurant/src/lib.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |     let order2 = Salad;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_order2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `serve_order`
[INFO] [stdout]  --> restaurant/src/lib.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn serve_order() {}
[INFO] [stdout]   |    ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::hash::Hash`
[INFO] [stdout]  --> collections/src/hashmap.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::hash::Hash;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `fix_incorrect_order`
[INFO] [stdout]   --> restaurant/src/lib.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 |     fn fix_incorrect_order() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `cook_order`
[INFO] [stdout]   --> restaurant/src/lib.rs:15:8
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn cook_order() {}
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `seasonal_fruit`
[INFO] [stdout]   --> restaurant/src/lib.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |         seasonal_fruit: String,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two`
[INFO] [stdout]  --> tests/src/test_organization.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn add_two(a: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]   --> tests/src/lib.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     value: i32,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `user2`
[INFO] [stdout]   --> structs/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let user2 = User {
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_user2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `black`
[INFO] [stdout]   --> structs/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let black = Color(0, 0, 0);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_black`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `origin`
[INFO] [stdout]   --> structs/src/main.rs:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let origin = Point(0, 0, 0);
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_origin`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `row`
[INFO] [stdout]   --> collections/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let row: Vec<SpreadsheetCell> = vec![
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_row`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> collections/src/strings.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let s = format!("{}-{}-{}", s1, s2, s3);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: cannot borrow `hash` as mutable because it is also borrowed as immutable
[INFO] [stdout]   --> collections/src/hashmap.rs:48:13
[INFO] [stdout]    |
[INFO] [stdout] 47 |         if let Some(value) = hash.get(i) {
[INFO] [stdout]    |                              ---- immutable borrow occurs here
[INFO] [stdout] 48 |             hash.insert(*i, value + 1);
[INFO] [stdout]    |             ^^^^            ----- immutable borrow later used here
[INFO] [stdout]    |             |
[INFO] [stdout]    |             mutable borrow occurs here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mutable_borrow_reservation_conflict)]` on by default
[INFO] [stdout]    = warning: this borrowing pattern was not meant to be accepted, and may become a hard error in the future
[INFO] [stdout]    = note: for more information, see issue #59159 <https://github.com/rust-lang/rust/issues/59159>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `email`
[INFO] [stdout]  --> structs/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     email: String,
[INFO] [stdout]   |     ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::hash::Hash`
[INFO] [stdout]  --> collections/src/hashmap.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::hash::Hash;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `sign_in_count`
[INFO] [stdout]  --> structs/src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     sign_in_count: u64,
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `active`
[INFO] [stdout]  --> structs/src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     active: bool,
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking errors v0.1.0 (/opt/rustwide/workdir/errors)
[INFO] [stdout] warning: function is never used: `iterator`
[INFO] [stdout]  --> functional_features/src/iterators.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn iterator() {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `shoes_in_size`
[INFO] [stdout]   --> functional_features/src/iterators.rs:14:4
[INFO] [stdout]    |
[INFO] [stdout] 14 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> functional_features/src/iterators.rs:63:8
[INFO] [stdout]    |
[INFO] [stdout] 63 |     fn new() -> Counter {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout`
[INFO] [stdout]   --> functional_features/src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn generate_workout(intensity: u32, random_number: u32) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout_with_closure`
[INFO] [stdout]   --> functional_features/src/main.rs:43:4
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn generate_workout_with_closure(intensity: u32, random_number: u32) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]   --> functional_features/src/main.rs:63:4
[INFO] [stdout]    |
[INFO] [stdout] 63 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Cacher`
[INFO] [stdout]   --> functional_features/src/main.rs:70:8
[INFO] [stdout]    |
[INFO] [stdout] 70 | struct Cacher<T, U>
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> functional_features/src/main.rs:84:8
[INFO] [stdout]    |
[INFO] [stdout] 84 |     fn new(calculation: T) -> Cacher<T, U> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `value`
[INFO] [stdout]   --> functional_features/src/main.rs:91:8
[INFO] [stdout]    |
[INFO] [stdout] 91 |     fn value(&mut self, arg: U) -> U {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout_with_struct`
[INFO] [stdout]    --> functional_features/src/main.rs:103:4
[INFO] [stdout]     |
[INFO] [stdout] 103 | fn generate_workout_with_struct(inversity: u32, random_number: u32) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::hash_map::RandomState`
[INFO] [stdout]  --> functional_features/src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::collections::hash_map::RandomState;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `name`
[INFO] [stdout]   --> tests/src/lib.rs:63:17
[INFO] [stdout]    |
[INFO] [stdout] 63 | pub fn greeting(name: &str) -> String {
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_name`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0502]: cannot borrow `s` as mutable because it is also borrowed as immutable
[INFO] [stdout]   --> ownership/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let word = first_word(&s);
[INFO] [stdout]    |                           -- immutable borrow occurs here
[INFO] [stdout] 24 |     s.clear();
[INFO] [stdout]    |     ^^^^^^^^^ mutable borrow occurs here
[INFO] [stdout] 25 |     println!("the first word is: {}", word);
[INFO] [stdout]    |                                       ---- immutable borrow later used here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two`
[INFO] [stdout]  --> tests/src/test_organization.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn add_two(a: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `internal_adder`
[INFO] [stdout]  --> tests/src/test_organization.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn internal_adder(a: i32, b: i32) -> i32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `can_hold`
[INFO] [stdout]   --> tests/src/lib.rs:58:8
[INFO] [stdout]    |
[INFO] [stdout] 58 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `value`
[INFO] [stdout]   --> tests/src/lib.rs:69:5
[INFO] [stdout]    |
[INFO] [stdout] 69 |     value: i32,
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> functional_features/src/improve_io.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     run(config);
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Map` that must be used
[INFO] [stdout]  --> functional_features/src/iterators.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     v1.iter().map(|x| x + 1);
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: iterators are lazy and do nothing unless consumed
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0502`.
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]    --> functional_features/src/main.rs:128:9
[INFO] [stdout]     |
[INFO] [stdout] 128 |     let v1 = c.value(1);
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> functional_features/src/main.rs:137:9
[INFO] [stdout]     |
[INFO] [stdout] 137 |     let y = 4;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ownership` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let home = IpAddr {
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `row`
[INFO] [stdout]   --> collections/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let row: Vec<SpreadsheetCell> = vec![
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_row`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> collections/src/strings.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let s = format!("{}-{}-{}", s1, s2, s3);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let home = IpAddr2::V4("127.0.0.1".to_string());
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |     let home = IpAddr3::V4(127, 0, 0, 1);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loopback`
[INFO] [stdout]   --> enums/src/main.rs:32:9
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let loopback = IpAddr3::V6("::1".to_string());
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loopback`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six`
[INFO] [stdout]   --> enums/src/matches.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let six = plus_one(Some(5));
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_six`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `none`
[INFO] [stdout]   --> enums/src/matches.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let none = plus_one(None);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_none`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alaska`
[INFO] [stdout]  --> enums/src/matches.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     Alaska,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterator`
[INFO] [stdout]  --> functional_features/src/iterators.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn iterator() {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout`
[INFO] [stdout]   --> functional_features/src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn generate_workout(intensity: u32, random_number: u32) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Penny`
[INFO] [stdout]  --> enums/src/matches.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Penny,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout_with_closure`
[INFO] [stdout]   --> functional_features/src/main.rs:43:4
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn generate_workout_with_closure(intensity: u32, random_number: u32) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]   --> functional_features/src/main.rs:63:4
[INFO] [stdout]    |
[INFO] [stdout] 63 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `generate_workout_with_struct`
[INFO] [stdout]    --> functional_features/src/main.rs:103:4
[INFO] [stdout]     |
[INFO] [stdout] 103 | fn generate_workout_with_struct(inversity: u32, random_number: u32) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nickel`
[INFO] [stdout]  --> enums/src/matches.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     Nickel,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Dime`
[INFO] [stdout]   --> enums/src/matches.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Dime,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `V6`
[INFO] [stdout]  --> enums/src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     V6,
[INFO] [stdout]   |     ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `kind`
[INFO] [stdout]   --> enums/src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     kind: IpAddrKind,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `address`
[INFO] [stdout]   --> enums/src/main.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     address: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `V6`
[INFO] [stdout]   --> enums/src/main.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     V6(String),
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: cannot borrow `hash` as mutable because it is also borrowed as immutable
[INFO] [stdout]   --> collections/src/hashmap.rs:48:13
[INFO] [stdout]    |
[INFO] [stdout] 47 |         if let Some(value) = hash.get(i) {
[INFO] [stdout]    |                              ---- immutable borrow occurs here
[INFO] [stdout] 48 |             hash.insert(*i, value + 1);
[INFO] [stdout]    |             ^^^^            ----- immutable borrow later used here
[INFO] [stdout]    |             |
[INFO] [stdout]    |             mutable borrow occurs here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mutable_borrow_reservation_conflict)]` on by default
[INFO] [stdout]    = warning: this borrowing pattern was not meant to be accepted, and may become a hard error in the future
[INFO] [stdout]    = note: for more information, see issue #59159 <https://github.com/rust-lang/rust/issues/59159>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> functional_features/src/improve_io.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     run(config);
[INFO] [stdout]    |     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Map` that must be used
[INFO] [stdout]  --> functional_features/src/iterators.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     v1.iter().map(|x| x + 1);
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: iterators are lazy and do nothing unless consumed
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 14 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Error`
[INFO] [stdout]  --> errors/src/main.rs:4:15
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::{Error, ErrorKind, Read};
[INFO] [stdout]   |               ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::panic::panic_any`
[INFO] [stdout]  --> errors/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::panic::panic_any;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     let f = match f {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let f = File::open(file_name).unwrap_or_else(|error| {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |     let f = File::open("unwrap.txt").unwrap();
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> errors/src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let mut secret_number: i32 = 0;
[INFO] [stdout]    |         ----^^^^^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file`
[INFO] [stdout]   --> errors/src/main.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file2`
[INFO] [stdout]   --> errors/src/main.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn read_username_from_file2() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file3`
[INFO] [stdout]   --> errors/src/main.rs:43:4
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn read_username_from_file3() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `backtrace`
[INFO] [stdout]   --> errors/src/main.rs:51:4
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn backtrace() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_or_create`
[INFO] [stdout]   --> errors/src/main.rs:56:4
[INFO] [stdout]    |
[INFO] [stdout] 56 | fn file_read_or_create() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_or_create_closure`
[INFO] [stdout]   --> errors/src/main.rs:72:4
[INFO] [stdout]    |
[INFO] [stdout] 72 | fn file_read_or_create_closure() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_unwrap`
[INFO] [stdout]   --> errors/src/main.rs:84:4
[INFO] [stdout]    |
[INFO] [stdout] 84 | fn file_read_unwrap() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::largest`
[INFO] [stdout]  --> generics/src/lifetime.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use crate::largest;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::largest`
[INFO] [stdout]  --> generics/src/lifetime.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use crate::largest;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Error`
[INFO] [stdout]  --> errors/src/main.rs:4:15
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::{Error, ErrorKind, Read};
[INFO] [stdout]   |               ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::panic::panic_any`
[INFO] [stdout]  --> errors/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::panic::panic_any;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     let f = match f {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:74:9
[INFO] [stdout]    |
[INFO] [stdout] 74 |     let f = File::open(file_name).unwrap_or_else(|error| {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> errors/src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |     let f = File::open("unwrap.txt").unwrap();
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let home = IpAddr {
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let home = IpAddr2::V4("127.0.0.1".to_string());
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]   --> enums/src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |     let home = IpAddr3::V4(127, 0, 0, 1);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loopback`
[INFO] [stdout]   --> enums/src/main.rs:32:9
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let loopback = IpAddr3::V6("::1".to_string());
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loopback`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six`
[INFO] [stdout]   --> enums/src/matches.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let six = plus_one(Some(5));
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_six`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `none`
[INFO] [stdout]   --> enums/src/matches.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let none = plus_one(None);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_none`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alaska`
[INFO] [stdout]  --> enums/src/matches.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     Alaska,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Penny`
[INFO] [stdout]  --> enums/src/matches.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Penny,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nickel`
[INFO] [stdout]  --> enums/src/matches.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     Nickel,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Dime`
[INFO] [stdout]   --> enums/src/matches.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     Dime,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `V6`
[INFO] [stdout]  --> enums/src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     V6,
[INFO] [stdout]   |     ^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `kind`
[INFO] [stdout]   --> enums/src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     kind: IpAddrKind,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `address`
[INFO] [stdout]   --> enums/src/main.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     address: String,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `V6`
[INFO] [stdout]   --> enums/src/main.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     V6(String),
[INFO] [stdout]    |     ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> errors/src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let mut secret_number: i32 = 0;
[INFO] [stdout]    |         ----^^^^^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file`
[INFO] [stdout]   --> errors/src/main.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn read_username_from_file() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file2`
[INFO] [stdout]   --> errors/src/main.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn read_username_from_file2() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `read_username_from_file3`
[INFO] [stdout]   --> errors/src/main.rs:43:4
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn read_username_from_file3() -> Result<String, io::Error> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> generics/src/lifetime.rs:63:26
[INFO] [stdout]    |
[INFO] [stdout] 63 | fn pick1<'a>(x: &'a str, y: &str) -> &'a str {
[INFO] [stdout]    |                          ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `backtrace`
[INFO] [stdout]   --> errors/src/main.rs:51:4
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn backtrace() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_or_create`
[INFO] [stdout]   --> errors/src/main.rs:56:4
[INFO] [stdout]    |
[INFO] [stdout] 56 | fn file_read_or_create() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_or_create_closure`
[INFO] [stdout]   --> errors/src/main.rs:72:4
[INFO] [stdout]    |
[INFO] [stdout] 72 | fn file_read_or_create_closure() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> generics/src/traits.rs:73:24
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `file_read_unwrap`
[INFO] [stdout]   --> errors/src/main.rs:84:4
[INFO] [stdout]    |
[INFO] [stdout] 84 | fn file_read_unwrap() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> generics/src/traits.rs:73:31
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_word`
[INFO] [stdout]   --> generics/src/lifetime.rs:95:4
[INFO] [stdout]    |
[INFO] [stdout] 95 | fn first_word(s: &str) -> &str {
[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: `level`
[INFO] [stdout]    --> generics/src/lifetime.rs:116:8
[INFO] [stdout]     |
[INFO] [stdout] 116 |     fn level(&self) -> i32 {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `announce_and_return_part`
[INFO] [stdout]    --> generics/src/lifetime.rs:121:8
[INFO] [stdout]     |
[INFO] [stdout] 121 |     fn announce_and_return_part(&self, announcement: &str) -> &str {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `longest_with_an_announcement`
[INFO] [stdout]    --> generics/src/lifetime.rs:129:4
[INFO] [stdout]     |
[INFO] [stdout] 129 | fn longest_with_an_announcement<'a, T>(x: &'a str, y: &'a str, ann: T) -> &'a str
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify2`
[INFO] [stdout]   --> generics/src/traits.rs:69:4
[INFO] [stdout]    |
[INFO] [stdout] 69 | fn notify2<T: Summary>(item: &T) {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function`
[INFO] [stdout]   --> generics/src/traits.rs:73:4
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> generics/src/lifetime.rs:63:26
[INFO] [stdout]    |
[INFO] [stdout] 63 | fn pick1<'a>(x: &'a str, y: &str) -> &'a str {
[INFO] [stdout]    |                          ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> generics/src/traits.rs:73:24
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> generics/src/traits.rs:73:31
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |                               ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0502]: cannot borrow `s` as mutable because it is also borrowed as immutable
[INFO] [stdout]   --> ownership/src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let word = first_word(&s);
[INFO] [stdout]    |                           -- immutable borrow occurs here
[INFO] [stdout] 24 |     s.clear();
[INFO] [stdout]    |     ^^^^^^^^^ mutable borrow occurs here
[INFO] [stdout] 25 |     println!("the first word is: {}", word);
[INFO] [stdout]    |                                       ---- immutable borrow later used here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0502`.
[INFO] [stdout] 
[INFO] [stdout] warning: 14 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_word`
[INFO] [stdout]   --> generics/src/lifetime.rs:95:4
[INFO] [stdout]    |
[INFO] [stdout] 95 | fn first_word(s: &str) -> &str {
[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: `level`
[INFO] [stdout]    --> generics/src/lifetime.rs:116:8
[INFO] [stdout]     |
[INFO] [stdout] 116 |     fn level(&self) -> i32 {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `announce_and_return_part`
[INFO] [stdout]    --> generics/src/lifetime.rs:121:8
[INFO] [stdout]     |
[INFO] [stdout] 121 |     fn announce_and_return_part(&self, announcement: &str) -> &str {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `longest_with_an_announcement`
[INFO] [stdout]    --> generics/src/lifetime.rs:129:4
[INFO] [stdout]     |
[INFO] [stdout] 129 | fn longest_with_an_announcement<'a, T>(x: &'a str, y: &'a str, ann: T) -> &'a str
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `notify2`
[INFO] [stdout]   --> generics/src/traits.rs:69:4
[INFO] [stdout]    |
[INFO] [stdout] 69 | fn notify2<T: Summary>(item: &T) {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `some_function`
[INFO] [stdout]   --> generics/src/traits.rs:73:4
[INFO] [stdout]    |
[INFO] [stdout] 73 | fn some_function<T, U>(t: &T, u: &U)
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "459c0005cf720eccd9fe5c0ae4fad43ff883e5c7d3d4e0554186d7866f6c88a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "459c0005cf720eccd9fe5c0ae4fad43ff883e5c7d3d4e0554186d7866f6c88a5", kill_on_drop: false }`
[INFO] [stdout] 459c0005cf720eccd9fe5c0ae4fad43ff883e5c7d3d4e0554186d7866f6c88a5