[INFO] cloning repository https://github.com/maomingan/rust_practice
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/maomingan/rust_practice" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmaomingan%2Frust_practice", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmaomingan%2Frust_practice'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9504945cfb8e9f2f8875a21467c5cc553d75ca81
[INFO] checking maomingan/rust_practice against master#4b596bbd847672da87763b76171687d3544863c2 for pr-144544
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmaomingan%2Frust_practice" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/maomingan/rust_practice
[INFO] finished tweaking git repo https://github.com/maomingan/rust_practice
[INFO] tweaked toml for git repo https://github.com/maomingan/rust_practice written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/maomingan/rust_practice on toolchain 4b596bbd847672da87763b76171687d3544863c2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4b596bbd847672da87763b76171687d3544863c2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/maomingan/rust_practice already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4b596bbd847672da87763b76171687d3544863c2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4b596bbd847672da87763b76171687d3544863c2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2adbd79081284162fe47494d23ea3243ecfe00a8afba3ea7597b55c5f9e9c52a
[INFO] running `Command { std: "docker" "start" "-a" "2adbd79081284162fe47494d23ea3243ecfe00a8afba3ea7597b55c5f9e9c52a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2adbd79081284162fe47494d23ea3243ecfe00a8afba3ea7597b55c5f9e9c52a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2adbd79081284162fe47494d23ea3243ecfe00a8afba3ea7597b55c5f9e9c52a", kill_on_drop: false }`
[INFO] [stdout] 2adbd79081284162fe47494d23ea3243ecfe00a8afba3ea7597b55c5f9e9c52a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+4b596bbd847672da87763b76171687d3544863c2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cc4219b44c008d936b6c5995839c032dadeaa60fe148ccf8f2bad191b1010699
[INFO] running `Command { std: "docker" "start" "-a" "cc4219b44c008d936b6c5995839c032dadeaa60fe148ccf8f2bad191b1010699", kill_on_drop: false }`
[INFO] [stderr]     Checking rust_practice v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `variables::variables`
[INFO] [stdout]  --> src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use variables::variables;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `datatype::datatype`
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use datatype::datatype;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_i`
[INFO] [stdout]  --> src/datatype.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let number_i = 23; // 有符号整形，可以表示负数
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_i`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_u`
[INFO] [stdout]  --> src/datatype.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let number_u: u32 = 23; // 无符号整形，只能表示正数
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_f`
[INFO] [stdout]  --> src/datatype.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let number_f = 0.2; // 双精度浮点
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_f32`
[INFO] [stdout]  --> src/datatype.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let number_f32: f32 = 0.2;  // 单精度浮点
[INFO] [stdout]   |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_f32`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/datatype.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let b = false;  // 布尔
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/datatype.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let c = 'Z';    // char，四字节，单引号
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> src/datatype.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let s = "Z";    // 字符串
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `s` is never read
[INFO] [stdout]  --> src/refstring.rs:3:13
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let mut s = "a";
[INFO] [stdout]   |             ^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]  --> src/refstring.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let s2 = s;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ss2`
[INFO] [stdout]   --> src/refstring.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let ss2 = ss.clone();
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_ss2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let word = first_word(&my_string[0..6]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let word = first_word(&my_string[..]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let word = first_word(&my_string);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let word = first_word(&my_string_literal[0..6]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let word = first_word(&my_string_literal[..]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `variables::variables`
[INFO] [stdout]  --> src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use variables::variables;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `datatype::datatype`
[INFO] [stdout]   --> src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 | use datatype::datatype;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `variables` is never used
[INFO] [stdout]  --> src/variables.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn variables() {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `datatype` is never used
[INFO] [stdout]  --> src/datatype.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn datatype() {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_if` is never used
[INFO] [stdout]  --> src/control.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn control_if(number: i32){
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_if_let` is never used
[INFO] [stdout]   --> src/control.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub fn control_if_let(b: bool) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_loop` is never used
[INFO] [stdout]   --> src/control.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn control_loop () {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_while` is never used
[INFO] [stdout]   --> src/control.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub fn control_while () {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_for` is never used
[INFO] [stdout]   --> src/control.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | pub fn control_for () {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `in_params` is never used
[INFO] [stdout]  --> src/func.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn in_params(x: i32, y: i32) {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `return_result` is never used
[INFO] [stdout]  --> src/func.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn return_result(x: i32, y: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `ref_test` is never used
[INFO] [stdout]  --> src/refstring.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn ref_test () {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_string` is never used
[INFO] [stdout]   --> src/refstring.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn test_string(str: String){
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_slice` is never used
[INFO] [stdout]   --> src/slice.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub fn test_slice () {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `first_word` is never used
[INFO] [stdout]   --> src/slice.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn first_word(s: &str) -> &str {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]  --> src/struct_demo.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test` is never used
[INFO] [stdout]  --> src/struct_demo.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub fn test () {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cal_area` is never used
[INFO] [stdout]   --> src/struct_demo.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn cal_area (rectangle: &Rectangle) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test2` is never used
[INFO] [stdout]   --> src/struct_demo.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn test2 () {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cal_area` is never used
[INFO] [stdout]   --> src/struct_demo.rs:32:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 32 |     fn cal_area (&self) -> u32 {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test3` is never used
[INFO] [stdout]   --> src/struct_demo.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | pub fn test3 () {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `can_hold` is never used
[INFO] [stdout]   --> src/struct_demo.rs:56:8
[INFO] [stdout]    |
[INFO] [stdout] 55 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 56 |     fn can_hold (&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_i`
[INFO] [stdout]  --> src/datatype.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let number_i = 23; // 有符号整形，可以表示负数
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_i`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_u`
[INFO] [stdout]  --> src/datatype.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let number_u: u32 = 23; // 无符号整形，只能表示正数
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_f`
[INFO] [stdout]  --> src/datatype.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let number_f = 0.2; // 双精度浮点
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `number_f32`
[INFO] [stdout]  --> src/datatype.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let number_f32: f32 = 0.2;  // 单精度浮点
[INFO] [stdout]   |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_number_f32`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]  --> src/datatype.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let b = false;  // 布尔
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/datatype.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let c = 'Z';    // char，四字节，单引号
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> src/datatype.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let s = "Z";    // 字符串
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `s` is never read
[INFO] [stdout]  --> src/refstring.rs:3:13
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let mut s = "a";
[INFO] [stdout]   |             ^
[INFO] [stdout]   |
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s2`
[INFO] [stdout]  --> src/refstring.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let s2 = s;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_s2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ss2`
[INFO] [stdout]   --> src/refstring.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     let ss2 = ss.clone();
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_ss2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let word = first_word(&my_string[0..6]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let word = first_word(&my_string[..]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let word = first_word(&my_string);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let word = first_word(&my_string_literal[0..6]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/slice.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let word = first_word(&my_string_literal[..]);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `variables` is never used
[INFO] [stdout]  --> src/variables.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn variables() {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `datatype` is never used
[INFO] [stdout]  --> src/datatype.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn datatype() {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_if` is never used
[INFO] [stdout]  --> src/control.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn control_if(number: i32){
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_if_let` is never used
[INFO] [stdout]   --> src/control.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub fn control_if_let(b: bool) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_loop` is never used
[INFO] [stdout]   --> src/control.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn control_loop () {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_while` is never used
[INFO] [stdout]   --> src/control.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 | pub fn control_while () {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `control_for` is never used
[INFO] [stdout]   --> src/control.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | pub fn control_for () {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `in_params` is never used
[INFO] [stdout]  --> src/func.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn in_params(x: i32, y: i32) {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `return_result` is never used
[INFO] [stdout]  --> src/func.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn return_result(x: i32, y: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `ref_test` is never used
[INFO] [stdout]  --> src/refstring.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn ref_test () {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_string` is never used
[INFO] [stdout]   --> src/refstring.rs:19:4
[INFO] [stdout]    |
[INFO] [stdout] 19 | fn test_string(str: String){
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_slice` is never used
[INFO] [stdout]   --> src/slice.rs:12:8
[INFO] [stdout]    |
[INFO] [stdout] 12 | pub fn test_slice () {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `first_word` is never used
[INFO] [stdout]   --> src/slice.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn first_word(s: &str) -> &str {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]  --> src/struct_demo.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Rectangle {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test` is never used
[INFO] [stdout]  --> src/struct_demo.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub fn test () {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cal_area` is never used
[INFO] [stdout]   --> src/struct_demo.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn cal_area (rectangle: &Rectangle) -> u32 {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test2` is never used
[INFO] [stdout]   --> src/struct_demo.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | pub fn test2 () {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cal_area` is never used
[INFO] [stdout]   --> src/struct_demo.rs:32:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 32 |     fn cal_area (&self) -> u32 {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test3` is never used
[INFO] [stdout]   --> src/struct_demo.rs:37:8
[INFO] [stdout]    |
[INFO] [stdout] 37 | pub fn test3 () {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `can_hold` is never used
[INFO] [stdout]   --> src/struct_demo.rs:56:8
[INFO] [stdout]    |
[INFO] [stdout] 55 | impl Rectangle {
[INFO] [stdout]    | -------------- method in this implementation
[INFO] [stdout] 56 |     fn can_hold (&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.29s
[INFO] running `Command { std: "docker" "inspect" "cc4219b44c008d936b6c5995839c032dadeaa60fe148ccf8f2bad191b1010699", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cc4219b44c008d936b6c5995839c032dadeaa60fe148ccf8f2bad191b1010699", kill_on_drop: false }`
[INFO] [stdout] cc4219b44c008d936b6c5995839c032dadeaa60fe148ccf8f2bad191b1010699