[INFO] cloning repository https://github.com/chrisp9/rust_exploration
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/chrisp9/rust_exploration" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 08c29e33beb024b8d3a51e551724e279bf8a4a9f
[INFO] testing chrisp9/rust_exploration against beta-2020-10-09 for beta-1.48-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration" "/workspace/builds/worker-13/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/chrisp9/rust_exploration on toolchain beta-2020-10-09
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/chrisp9/rust_exploration
[INFO] finished tweaking git repo https://github.com/chrisp9/rust_exploration
[INFO] tweaked toml for git repo https://github.com/chrisp9/rust_exploration written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/chrisp9/rust_exploration already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e5d496fb983085e5172295ad58c69fe7c9aacec5638c0b68749af07632d2d23c
[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" "e5d496fb983085e5172295ad58c69fe7c9aacec5638c0b68749af07632d2d23c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e5d496fb983085e5172295ad58c69fe7c9aacec5638c0b68749af07632d2d23c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5d496fb983085e5172295ad58c69fe7c9aacec5638c0b68749af07632d2d23c", kill_on_drop: false }`
[INFO] [stdout] e5d496fb983085e5172295ad58c69fe7c9aacec5638c0b68749af07632d2d23c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 904a648b33ce277af3ab391ac36c511fa609006aea3394c45859f47609fe0092
[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" "904a648b33ce277af3ab391ac36c511fa609006aea3394c45859f47609fe0092", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_exploration v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]    --> src/main.rs:177:45
[INFO] [stdout]     |
[INFO] [stdout] 177 |     let mut expensive_result = Cacher::new(|num| {
[INFO] [stdout]     |                                             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `equal_to_x`
[INFO] [stdout]    --> src/main.rs:212:9
[INFO] [stdout]     |
[INFO] [stdout] 212 |     let equal_to_x = |z : u32| z == x;
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_equal_to_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:213:9
[INFO] [stdout]     |
[INFO] [stdout] 213 |     let y = 4;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `res`
[INFO] [stdout]    --> src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let res: Vec<_> = v1.iter().map(|x| x + 1).collect();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_res`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]    --> src/main.rs:236:9
[INFO] [stdout]     |
[INFO] [stdout] 236 |     let total: i32 = v1_iter.sum();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let item = map.get(&key).unwrap();
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:296:9
[INFO] [stdout]     |
[INFO] [stdout] 296 |     let s3 = s1 + &s2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:306:9
[INFO] [stdout]     |
[INFO] [stdout] 306 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `third`
[INFO] [stdout]    --> src/main.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |     let third: &i32 = &v[2];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_third`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:372:9
[INFO] [stdout]     |
[INFO] [stdout] 372 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_string`
[INFO] [stdout]    --> src/main.rs:373:9
[INFO] [stdout]     |
[INFO] [stdout] 373 |     let some_string = Some("A string");
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:375:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |     let absent_number : Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rect3`
[INFO] [stdout]    --> src/main.rs:387:9
[INFO] [stdout]     |
[INFO] [stdout] 387 |     let rect3 = Rectangle {width: 60, height: 45};
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_rect3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Pair`
[INFO] [stdout]   --> src/main.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Pair<T> {
[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: `new`
[INFO] [stdout]   --> src/main.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `cmp_display`
[INFO] [stdout]   --> src/main.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn cmp_display(&self) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `User`
[INFO] [stdout]   --> src/main.rs:42:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | struct User {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Rectangle`
[INFO] [stdout]   --> src/main.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 | struct Rectangle {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `area`
[INFO] [stdout]   --> src/main.rs:55:8
[INFO] [stdout]    |
[INFO] [stdout] 55 |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `can_hold`
[INFO] [stdout]   --> src/main.rs:59:8
[INFO] [stdout]    |
[INFO] [stdout] 59 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `square`
[INFO] [stdout]   --> src/main.rs:63:8
[INFO] [stdout]    |
[INFO] [stdout] 63 |     fn square(size: u32) -> Rectangle {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `IpAddrKind`
[INFO] [stdout]   --> src/main.rs:68:6
[INFO] [stdout]    |
[INFO] [stdout] 68 | enum IpAddrKind {
[INFO] [stdout]    |      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alabama`
[INFO] [stdout]   --> src/main.rs:75:5
[INFO] [stdout]    |
[INFO] [stdout] 75 |     Alabama,
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alaska`
[INFO] [stdout]   --> src/main.rs:76:5
[INFO] [stdout]    |
[INFO] [stdout] 76 |     Alaska,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Coin`
[INFO] [stdout]   --> src/main.rs:80:6
[INFO] [stdout]    |
[INFO] [stdout] 80 | enum Coin {
[INFO] [stdout]    |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Message`
[INFO] [stdout]   --> src/main.rs:87:6
[INFO] [stdout]    |
[INFO] [stdout] 87 | enum Message {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `call`
[INFO] [stdout]   --> src/main.rs:95:8
[INFO] [stdout]    |
[INFO] [stdout] 95 |     fn call(&self) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `largest`
[INFO] [stdout]    --> src/main.rs:100:5
[INFO] [stdout]     |
[INFO] [stdout] 100 |  fn largest<T : PartialOrd>(list: &[T]) -> &T {
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Point`
[INFO] [stdout]    --> src/main.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | struct Point<T> {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `shoes_in_my_size`
[INFO] [stdout]    --> src/main.rs:123:4
[INFO] [stdout]     |
[INFO] [stdout] 123 | fn shoes_in_my_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]    --> src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `closure_capturing_context`
[INFO] [stdout]    --> src/main.rs:210:4
[INFO] [stdout]     |
[INFO] [stdout] 210 | fn closure_capturing_context() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterators`
[INFO] [stdout]    --> src/main.rs:217:4
[INFO] [stdout]     |
[INFO] [stdout] 217 | fn iterators() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterator_map`
[INFO] [stdout]    --> src/main.rs:226:4
[INFO] [stdout]     |
[INFO] [stdout] 226 | fn iterator_map() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterator_sum`
[INFO] [stdout]    --> src/main.rs:232:4
[INFO] [stdout]     |
[INFO] [stdout] 232 | fn iterator_sum() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `news_aggregate`
[INFO] [stdout]    --> src/main.rs:269:4
[INFO] [stdout]     |
[INFO] [stdout] 269 | fn news_aggregate() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `vector`
[INFO] [stdout]    --> src/main.rs:305:4
[INFO] [stdout]     |
[INFO] [stdout] 305 | fn vector() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]    --> src/main.rs:330:8
[INFO] [stdout]     |
[INFO] [stdout] 330 |     fn new() -> Counter {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `if_let`
[INFO] [stdout]    --> src/main.rs:351:4
[INFO] [stdout]     |
[INFO] [stdout] 351 | fn if_let() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `value_in_cents`
[INFO] [stdout]    --> src/main.rs:359:4
[INFO] [stdout]     |
[INFO] [stdout] 359 | fn value_in_cents(coin : Coin) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `option`
[INFO] [stdout]    --> src/main.rs:371:4
[INFO] [stdout]     |
[INFO] [stdout] 371 | fn option() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `messages`
[INFO] [stdout]    --> src/main.rs:378:4
[INFO] [stdout]     |
[INFO] [stdout] 378 | fn messages() {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rectangles`
[INFO] [stdout]    --> src/main.rs:383:4
[INFO] [stdout]     |
[INFO] [stdout] 383 | fn rectangles() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `build_user`
[INFO] [stdout]    --> src/main.rs:395:4
[INFO] [stdout]     |
[INFO] [stdout] 395 | fn build_user(email: String, username: String) -> User {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `coins`
[INFO] [stdout]    --> src/main.rs:404:4
[INFO] [stdout]     |
[INFO] [stdout] 404 | fn coins() {
[INFO] [stdout]     |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `slices`
[INFO] [stdout]    --> src/main.rs:409:4
[INFO] [stdout]     |
[INFO] [stdout] 409 | fn slices() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `takes_ownership`
[INFO] [stdout]    --> src/main.rs:419:4
[INFO] [stdout]     |
[INFO] [stdout] 419 | fn takes_ownership(some_string: String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `makes_copy`
[INFO] [stdout]    --> src/main.rs:423:4
[INFO] [stdout]     |
[INFO] [stdout] 423 | fn makes_copy(some_integer: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_word`
[INFO] [stdout]    --> src/main.rs:427:4
[INFO] [stdout]     |
[INFO] [stdout] 427 | fn first_word(s: &String) -> usize {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `guess_number`
[INFO] [stdout]    --> src/main.rs:440:4
[INFO] [stdout]     |
[INFO] [stdout] 440 | fn guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/main.rs:245:5
[INFO] [stdout]     |
[INFO] [stdout] 245 |     read_username_from_file();
[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: 51 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.93s
[INFO] running `Command { std: "docker" "inspect" "904a648b33ce277af3ab391ac36c511fa609006aea3394c45859f47609fe0092", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "904a648b33ce277af3ab391ac36c511fa609006aea3394c45859f47609fe0092", kill_on_drop: false }`
[INFO] [stdout] 904a648b33ce277af3ab391ac36c511fa609006aea3394c45859f47609fe0092
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen" "--no-run" "--message-format=json", 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] e5105c234e53d312e125896a560b5e85acd1e1b3b8a1247c581f50f9a04070f2
[INFO] running `Command { std: "docker" "start" "-a" "e5105c234e53d312e125896a560b5e85acd1e1b3b8a1247c581f50f9a04070f2", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_exploration v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]    --> src/main.rs:177:45
[INFO] [stdout]     |
[INFO] [stdout] 177 |     let mut expensive_result = Cacher::new(|num| {
[INFO] [stdout]     |                                             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `equal_to_x`
[INFO] [stdout]    --> src/main.rs:212:9
[INFO] [stdout]     |
[INFO] [stdout] 212 |     let equal_to_x = |z : u32| z == x;
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_equal_to_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:213:9
[INFO] [stdout]     |
[INFO] [stdout] 213 |     let y = 4;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `res`
[INFO] [stdout]    --> src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let res: Vec<_> = v1.iter().map(|x| x + 1).collect();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_res`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]    --> src/main.rs:236:9
[INFO] [stdout]     |
[INFO] [stdout] 236 |     let total: i32 = v1_iter.sum();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let item = map.get(&key).unwrap();
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:296:9
[INFO] [stdout]     |
[INFO] [stdout] 296 |     let s3 = s1 + &s2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:306:9
[INFO] [stdout]     |
[INFO] [stdout] 306 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `third`
[INFO] [stdout]    --> src/main.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |     let third: &i32 = &v[2];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_third`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:372:9
[INFO] [stdout]     |
[INFO] [stdout] 372 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_string`
[INFO] [stdout]    --> src/main.rs:373:9
[INFO] [stdout]     |
[INFO] [stdout] 373 |     let some_string = Some("A string");
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:375:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |     let absent_number : Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rect3`
[INFO] [stdout]    --> src/main.rs:387:9
[INFO] [stdout]     |
[INFO] [stdout] 387 |     let rect3 = Rectangle {width: 60, height: 45};
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_rect3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Pair`
[INFO] [stdout]   --> src/main.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Pair<T> {
[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: `new`
[INFO] [stdout]   --> src/main.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `cmp_display`
[INFO] [stdout]   --> src/main.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn cmp_display(&self) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `User`
[INFO] [stdout]   --> src/main.rs:42:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | struct User {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Rectangle`
[INFO] [stdout]   --> src/main.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 | struct Rectangle {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `area`
[INFO] [stdout]   --> src/main.rs:55:8
[INFO] [stdout]    |
[INFO] [stdout] 55 |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `can_hold`
[INFO] [stdout]   --> src/main.rs:59:8
[INFO] [stdout]    |
[INFO] [stdout] 59 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `square`
[INFO] [stdout]   --> src/main.rs:63:8
[INFO] [stdout]    |
[INFO] [stdout] 63 |     fn square(size: u32) -> Rectangle {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `IpAddrKind`
[INFO] [stdout]   --> src/main.rs:68:6
[INFO] [stdout]    |
[INFO] [stdout] 68 | enum IpAddrKind {
[INFO] [stdout]    |      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alabama`
[INFO] [stdout]   --> src/main.rs:75:5
[INFO] [stdout]    |
[INFO] [stdout] 75 |     Alabama,
[INFO] [stdout]    |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Alaska`
[INFO] [stdout]   --> src/main.rs:76:5
[INFO] [stdout]    |
[INFO] [stdout] 76 |     Alaska,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Coin`
[INFO] [stdout]   --> src/main.rs:80:6
[INFO] [stdout]    |
[INFO] [stdout] 80 | enum Coin {
[INFO] [stdout]    |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Message`
[INFO] [stdout]   --> src/main.rs:87:6
[INFO] [stdout]    |
[INFO] [stdout] 87 | enum Message {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `call`
[INFO] [stdout]   --> src/main.rs:95:8
[INFO] [stdout]    |
[INFO] [stdout] 95 |     fn call(&self) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `largest`
[INFO] [stdout]    --> src/main.rs:100:5
[INFO] [stdout]     |
[INFO] [stdout] 100 |  fn largest<T : PartialOrd>(list: &[T]) -> &T {
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Point`
[INFO] [stdout]    --> src/main.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | struct Point<T> {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stdout]    --> src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `closure_capturing_context`
[INFO] [stdout]    --> src/main.rs:210:4
[INFO] [stdout]     |
[INFO] [stdout] 210 | fn closure_capturing_context() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterators`
[INFO] [stdout]    --> src/main.rs:217:4
[INFO] [stdout]     |
[INFO] [stdout] 217 | fn iterators() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterator_map`
[INFO] [stdout]    --> src/main.rs:226:4
[INFO] [stdout]     |
[INFO] [stdout] 226 | fn iterator_map() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `iterator_sum`
[INFO] [stdout]    --> src/main.rs:232:4
[INFO] [stdout]     |
[INFO] [stdout] 232 | fn iterator_sum() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `news_aggregate`
[INFO] [stdout]    --> src/main.rs:269:4
[INFO] [stdout]     |
[INFO] [stdout] 269 | fn news_aggregate() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `vector`
[INFO] [stdout]    --> src/main.rs:305:4
[INFO] [stdout]     |
[INFO] [stdout] 305 | fn vector() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]    --> src/main.rs:330:8
[INFO] [stdout]     |
[INFO] [stdout] 330 |     fn new() -> Counter {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `if_let`
[INFO] [stdout]    --> src/main.rs:351:4
[INFO] [stdout]     |
[INFO] [stdout] 351 | fn if_let() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `value_in_cents`
[INFO] [stdout]    --> src/main.rs:359:4
[INFO] [stdout]     |
[INFO] [stdout] 359 | fn value_in_cents(coin : Coin) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `option`
[INFO] [stdout]    --> src/main.rs:371:4
[INFO] [stdout]     |
[INFO] [stdout] 371 | fn option() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `messages`
[INFO] [stdout]    --> src/main.rs:378:4
[INFO] [stdout]     |
[INFO] [stdout] 378 | fn messages() {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `rectangles`
[INFO] [stdout]    --> src/main.rs:383:4
[INFO] [stdout]     |
[INFO] [stdout] 383 | fn rectangles() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `build_user`
[INFO] [stdout]    --> src/main.rs:395:4
[INFO] [stdout]     |
[INFO] [stdout] 395 | fn build_user(email: String, username: String) -> User {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `coins`
[INFO] [stdout]    --> src/main.rs:404:4
[INFO] [stdout]     |
[INFO] [stdout] 404 | fn coins() {
[INFO] [stdout]     |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `slices`
[INFO] [stdout]    --> src/main.rs:409:4
[INFO] [stdout]     |
[INFO] [stdout] 409 | fn slices() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `takes_ownership`
[INFO] [stdout]    --> src/main.rs:419:4
[INFO] [stdout]     |
[INFO] [stdout] 419 | fn takes_ownership(some_string: String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `makes_copy`
[INFO] [stdout]    --> src/main.rs:423:4
[INFO] [stdout]     |
[INFO] [stdout] 423 | fn makes_copy(some_integer: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `first_word`
[INFO] [stdout]    --> src/main.rs:427:4
[INFO] [stdout]     |
[INFO] [stdout] 427 | fn first_word(s: &String) -> usize {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `guess_number`
[INFO] [stdout]    --> src/main.rs:440:4
[INFO] [stdout]     |
[INFO] [stdout] 440 | fn guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/main.rs:245:5
[INFO] [stdout]     |
[INFO] [stdout] 245 |     read_username_from_file();
[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: 50 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.52s
[INFO] running `Command { std: "docker" "inspect" "e5105c234e53d312e125896a560b5e85acd1e1b3b8a1247c581f50f9a04070f2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5105c234e53d312e125896a560b5e85acd1e1b3b8a1247c581f50f9a04070f2", kill_on_drop: false }`
[INFO] [stdout] e5105c234e53d312e125896a560b5e85acd1e1b3b8a1247c581f50f9a04070f2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=warn" "-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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 3fc9c5dde6e12b936bae5dd392114f1fe8fd02e2ada26f8ec713efb71ec31d8c
[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" "3fc9c5dde6e12b936bae5dd392114f1fe8fd02e2ada26f8ec713efb71ec31d8c", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unused variable: `num`
[INFO] [stdout] running 1 test
[INFO] [stderr]    --> src/main.rs:177:45
[INFO] [stdout] test filters_by_size ... ok
[INFO] [stderr]     |
[INFO] [stdout] 
[INFO] [stderr] 177 |     let mut expensive_result = Cacher::new(|num| {
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stderr]     |                                             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `equal_to_x`
[INFO] [stderr]    --> src/main.rs:212:9
[INFO] [stderr]     |
[INFO] [stderr] 212 |     let equal_to_x = |z : u32| z == x;
[INFO] [stderr]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_equal_to_x`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]    --> src/main.rs:213:9
[INFO] [stderr]     |
[INFO] [stderr] 213 |     let y = 4;
[INFO] [stderr]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `res`
[INFO] [stderr]    --> src/main.rs:229:9
[INFO] [stderr]     |
[INFO] [stderr] 229 |     let res: Vec<_> = v1.iter().map(|x| x + 1).collect();
[INFO] [stderr]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_res`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `total`
[INFO] [stderr]    --> src/main.rs:236:9
[INFO] [stderr]     |
[INFO] [stderr] 236 |     let total: i32 = v1_iter.sum();
[INFO] [stderr]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `item`
[INFO] [stderr]    --> src/main.rs:289:9
[INFO] [stderr]     |
[INFO] [stderr] 289 |     let item = map.get(&key).unwrap();
[INFO] [stderr]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s3`
[INFO] [stderr]    --> src/main.rs:296:9
[INFO] [stderr]     |
[INFO] [stderr] 296 |     let s3 = s1 + &s2;
[INFO] [stderr]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `v`
[INFO] [stderr]    --> src/main.rs:306:9
[INFO] [stderr]     |
[INFO] [stderr] 306 |     let v: Vec<i32> = Vec::new();
[INFO] [stderr]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `third`
[INFO] [stderr]    --> src/main.rs:309:9
[INFO] [stderr]     |
[INFO] [stderr] 309 |     let third: &i32 = &v[2];
[INFO] [stderr]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_third`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `some_number`
[INFO] [stderr]    --> src/main.rs:372:9
[INFO] [stderr]     |
[INFO] [stderr] 372 |     let some_number = Some(5);
[INFO] [stderr]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `some_string`
[INFO] [stderr]    --> src/main.rs:373:9
[INFO] [stderr]     |
[INFO] [stderr] 373 |     let some_string = Some("A string");
[INFO] [stderr]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_string`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `absent_number`
[INFO] [stderr]    --> src/main.rs:375:9
[INFO] [stderr]     |
[INFO] [stderr] 375 |     let absent_number : Option<i32> = None;
[INFO] [stderr]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `rect3`
[INFO] [stderr]    --> src/main.rs:387:9
[INFO] [stderr]     |
[INFO] [stderr] 387 |     let rect3 = Rectangle {width: 60, height: 45};
[INFO] [stderr]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_rect3`
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Pair`
[INFO] [stderr]   --> src/main.rs:18:8
[INFO] [stderr]    |
[INFO] [stderr] 18 | struct Pair<T> {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `new`
[INFO] [stderr]   --> src/main.rs:24:8
[INFO] [stderr]    |
[INFO] [stderr] 24 |     fn new(x: T, y: T) -> Self {
[INFO] [stderr]    |        ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `cmp_display`
[INFO] [stderr]   --> src/main.rs:33:8
[INFO] [stderr]    |
[INFO] [stderr] 33 |     fn cmp_display(&self) {
[INFO] [stderr]    |        ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `User`
[INFO] [stderr]   --> src/main.rs:42:8
[INFO] [stderr]    |
[INFO] [stderr] 42 | struct User {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Rectangle`
[INFO] [stderr]   --> src/main.rs:49:8
[INFO] [stderr]    |
[INFO] [stderr] 49 | struct Rectangle {
[INFO] [stderr]    |        ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `area`
[INFO] [stderr]   --> src/main.rs:55:8
[INFO] [stderr]    |
[INFO] [stderr] 55 |     fn area(&self) -> u32 {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `can_hold`
[INFO] [stderr]   --> src/main.rs:59:8
[INFO] [stderr]    |
[INFO] [stderr] 59 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stderr]    |        ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `square`
[INFO] [stderr]   --> src/main.rs:63:8
[INFO] [stderr]    |
[INFO] [stderr] 63 |     fn square(size: u32) -> Rectangle {
[INFO] [stderr]    |        ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `IpAddrKind`
[INFO] [stderr]   --> src/main.rs:68:6
[INFO] [stderr]    |
[INFO] [stderr] 68 | enum IpAddrKind {
[INFO] [stderr]    |      ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Alabama`
[INFO] [stderr]   --> src/main.rs:75:5
[INFO] [stderr]    |
[INFO] [stderr] 75 |     Alabama,
[INFO] [stderr]    |     ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `Alaska`
[INFO] [stderr]   --> src/main.rs:76:5
[INFO] [stderr]    |
[INFO] [stderr] 76 |     Alaska,
[INFO] [stderr]    |     ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Coin`
[INFO] [stderr]   --> src/main.rs:80:6
[INFO] [stderr]    |
[INFO] [stderr] 80 | enum Coin {
[INFO] [stderr]    |      ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Message`
[INFO] [stderr]   --> src/main.rs:87:6
[INFO] [stderr]    |
[INFO] [stderr] 87 | enum Message {
[INFO] [stderr]    |      ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `call`
[INFO] [stderr]   --> src/main.rs:95:8
[INFO] [stderr]    |
[INFO] [stderr] 95 |     fn call(&self) {
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `largest`
[INFO] [stderr]    --> src/main.rs:100:5
[INFO] [stderr]     |
[INFO] [stderr] 100 |  fn largest<T : PartialOrd>(list: &[T]) -> &T {
[INFO] [stderr]     |     ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Point`
[INFO] [stderr]    --> src/main.rs:112:8
[INFO] [stderr]     |
[INFO] [stderr] 112 | struct Point<T> {
[INFO] [stderr]     |        ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `simulated_expensive_calculation`
[INFO] [stderr]    --> src/main.rs:204:4
[INFO] [stderr]     |
[INFO] [stderr] 204 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `closure_capturing_context`
[INFO] [stderr]    --> src/main.rs:210:4
[INFO] [stderr]     |
[INFO] [stderr] 210 | fn closure_capturing_context() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `iterators`
[INFO] [stderr]    --> src/main.rs:217:4
[INFO] [stderr]     |
[INFO] [stderr] 217 | fn iterators() {
[INFO] [stderr]     |    ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `iterator_map`
[INFO] [stderr]    --> src/main.rs:226:4
[INFO] [stderr]     |
[INFO] [stderr] 226 | fn iterator_map() {
[INFO] [stderr]     |    ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `iterator_sum`
[INFO] [stderr]    --> src/main.rs:232:4
[INFO] [stderr]     |
[INFO] [stderr] 232 | fn iterator_sum() {
[INFO] [stderr]     |    ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `news_aggregate`
[INFO] [stderr]    --> src/main.rs:269:4
[INFO] [stderr]     |
[INFO] [stderr] 269 | fn news_aggregate() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `vector`
[INFO] [stderr]    --> src/main.rs:305:4
[INFO] [stderr]     |
[INFO] [stderr] 305 | fn vector() {
[INFO] [stderr]     |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `new`
[INFO] [stderr]    --> src/main.rs:330:8
[INFO] [stderr]     |
[INFO] [stderr] 330 |     fn new() -> Counter {
[INFO] [stderr]     |        ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `if_let`
[INFO] [stderr]    --> src/main.rs:351:4
[INFO] [stderr]     |
[INFO] [stderr] 351 | fn if_let() {
[INFO] [stderr]     |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `value_in_cents`
[INFO] [stderr]    --> src/main.rs:359:4
[INFO] [stderr]     |
[INFO] [stderr] 359 | fn value_in_cents(coin : Coin) -> u32 {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `option`
[INFO] [stderr]    --> src/main.rs:371:4
[INFO] [stderr]     |
[INFO] [stderr] 371 | fn option() {
[INFO] [stderr]     |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `messages`
[INFO] [stderr]    --> src/main.rs:378:4
[INFO] [stderr]     |
[INFO] [stderr] 378 | fn messages() {
[INFO] [stderr]     |    ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `rectangles`
[INFO] [stderr]    --> src/main.rs:383:4
[INFO] [stderr]     |
[INFO] [stderr] 383 | fn rectangles() {
[INFO] [stderr]     |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `build_user`
[INFO] [stderr]    --> src/main.rs:395:4
[INFO] [stderr]     |
[INFO] [stderr] 395 | fn build_user(email: String, username: String) -> User {
[INFO] [stderr]     |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `coins`
[INFO] [stderr]    --> src/main.rs:404:4
[INFO] [stderr]     |
[INFO] [stderr] 404 | fn coins() {
[INFO] [stderr]     |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `slices`
[INFO] [stderr]    --> src/main.rs:409:4
[INFO] [stderr]     |
[INFO] [stderr] 409 | fn slices() {
[INFO] [stderr]     |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `takes_ownership`
[INFO] [stderr]    --> src/main.rs:419:4
[INFO] [stderr]     |
[INFO] [stderr] 419 | fn takes_ownership(some_string: String) {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `makes_copy`
[INFO] [stderr]    --> src/main.rs:423:4
[INFO] [stderr]     |
[INFO] [stderr] 423 | fn makes_copy(some_integer: i32) {
[INFO] [stderr]     |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `first_word`
[INFO] [stderr]    --> src/main.rs:427:4
[INFO] [stderr]     |
[INFO] [stderr] 427 | fn first_word(s: &String) -> usize {
[INFO] [stderr]     |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `guess_number`
[INFO] [stderr]    --> src/main.rs:440:4
[INFO] [stderr]     |
[INFO] [stderr] 440 | fn guess_number() {
[INFO] [stderr]     |    ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]    --> src/main.rs:245:5
[INFO] [stderr]     |
[INFO] [stderr] 245 |     read_username_from_file();
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 50 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/rust_exploration-2741ce1110f44956
[INFO] running `Command { std: "docker" "inspect" "3fc9c5dde6e12b936bae5dd392114f1fe8fd02e2ada26f8ec713efb71ec31d8c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3fc9c5dde6e12b936bae5dd392114f1fe8fd02e2ada26f8ec713efb71ec31d8c", kill_on_drop: false }`
[INFO] [stdout] 3fc9c5dde6e12b936bae5dd392114f1fe8fd02e2ada26f8ec713efb71ec31d8c
