[INFO] cloning repository https://github.com/flamingoodev/rust-learn
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/flamingoodev/rust-learn" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflamingoodev%2Frust-learn", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflamingoodev%2Frust-learn'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 65219f1c946c48481807a8ef23d1e2322cab63e8
[INFO] checking flamingoodev/rust-learn against try#4a04890980766cc79878135f5ade8c0c4321e943 for pr-65819
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflamingoodev%2Frust-learn" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/flamingoodev/rust-learn on toolchain 4a04890980766cc79878135f5ade8c0c4321e943
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4a04890980766cc79878135f5ade8c0c4321e943" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/flamingoodev/rust-learn
[INFO] finished tweaking git repo https://github.com/flamingoodev/rust-learn
[INFO] tweaked toml for git repo https://github.com/flamingoodev/rust-learn written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/flamingoodev/rust-learn already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4a04890980766cc79878135f5ade8c0c4321e943" "fetch" "--locked" "--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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rand_hc v0.2.0
[INFO] [stderr]   Downloaded rand_core v0.5.1
[INFO] [stderr]   Downloaded rand_chacha v0.2.2
[INFO] [stderr]   Downloaded ppv-lite86 v0.2.8
[INFO] [stderr]   Downloaded getrandom v0.1.14
[INFO] [stderr]   Downloaded wasi v0.9.0+wasi-snapshot-preview1
[INFO] [stderr]   Downloaded rand v0.7.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/jobserver:/tmp/crater-runner-fifo:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+4a04890980766cc79878135f5ade8c0c4321e943" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9be3a9874b65f0a3ec1a636c04d81b79aade675a91f5206603bb3e969d85f114
[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" "9be3a9874b65f0a3ec1a636c04d81b79aade675a91f5206603bb3e969d85f114", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9be3a9874b65f0a3ec1a636c04d81b79aade675a91f5206603bb3e969d85f114", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9be3a9874b65f0a3ec1a636c04d81b79aade675a91f5206603bb3e969d85f114", kill_on_drop: false }`
[INFO] [stdout] 9be3a9874b65f0a3ec1a636c04d81b79aade675a91f5206603bb3e969d85f114
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/jobserver:/tmp/crater-runner-fifo:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTUP_TOOLCHAIN=4a04890980766cc79878135f5ade8c0c4321e943" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/tmp/crater-runner-fifo/jobserver-crater-fwd" "/opt/rustwide/cargo-home/bin/cargo" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a43fb2853bbbb433ae6db1e5a7cd149b2669db08031026beaf6ee21637c60945
[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" "a43fb2853bbbb433ae6db1e5a7cd149b2669db08031026beaf6ee21637c60945", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]     Checking ppv-lite86 v0.2.8
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking rust-learn v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io::Error`
[INFO] [stdout]  --> src/syntax/t_command.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Command`, `Output`
[INFO] [stdout]  --> src/syntax/t_command.rs:2:20
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::process::{Command, Output};
[INFO] [stdout]   |                    ^^^^^^^  ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::mem::size_of_val`
[INFO] [stdout]  --> src/tests/t_tests.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::mem::size_of_val;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io::Error`
[INFO] [stdout]  --> src/syntax/t_command.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Output`
[INFO] [stdout]  --> src/syntax/t_command.rs:2:29
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::process::{Command, Output};
[INFO] [stdout]   |                             ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y1`
[INFO] [stdout]   --> src/syntax/t_smart_pointer.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let y1 = x.borrow_mut();
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_y1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let num = 42u32;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let num: u32 = 42;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let num = 0x2A; // 十六进制
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let num = 0o106; // 八进制
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]   --> src/syntax/t_type.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let num = 3.55f64;
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/syntax/t_type.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut mut_arr = [1, 2, 3];
[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: `if_let`
[INFO] [stdout]   --> src/collections/t_vector.rs:57:4
[INFO] [stdout]    |
[INFO] [stdout] 57 | fn if_let() -> u8 {
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/collections/t_vector.rs:56:8
[INFO] [stdout]    |
[INFO] [stdout] 56 | #[warn(dead_code)]
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `while_let`
[INFO] [stdout]   --> src/collections/t_vector.rs:72:4
[INFO] [stdout]    |
[INFO] [stdout] 72 | fn while_let() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/collections/t_vector.rs:71:8
[INFO] [stdout]    |
[INFO] [stdout] 71 | #[warn(dead_code)]
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `pri_print_role`
[INFO] [stdout]  --> src/routes/role.rs:8:4
[INFO] [stdout]   |
[INFO] [stdout] 8 | fn pri_print_role() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]  --> src/routes/role.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | #[warn(dead_code)]
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `pri_print_user`
[INFO] [stdout]  --> src/routes/user.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn pri_print_user() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_master_pointer`
[INFO] [stdout]  --> src/smartpointer/t_smart_pointer.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn test_master_pointer() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `math`
[INFO] [stdout]  --> src/syntax/t_closure.rs:5:4
[INFO] [stdout]   |
[INFO] [stdout] 5 | fn math<F: Fn() -> i32>(op: F) -> i32 {
[INFO] [stdout]   |    ^^^^
[INFO] [stdout]   |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]  --> src/syntax/t_closure.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | #[warn(dead_code)]
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `two_times_impl`
[INFO] [stdout]   --> src/syntax/t_closure.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn two_times_impl() -> impl Fn(i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/syntax/t_closure.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | #[warn(dead_code)]
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `math`
[INFO] [stdout]  --> src/syntax/t_function.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn math(op: fn(i32, i32) -> i32, a: i32, b: i32) -> i32 {
[INFO] [stdout]   |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `sum`
[INFO] [stdout]  --> src/syntax/t_function.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn sum(a: i32, b: i32) -> i32 {
[INFO] [stdout]   |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `product`
[INFO] [stdout]   --> src/syntax/t_function.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn product(a: i32, b: i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `mat`
[INFO] [stdout]   --> src/syntax/t_function.rs:16:4
[INFO] [stdout]    |
[INFO] [stdout] 16 | fn mat(op: fn(i32, i32) -> i32, a: i32, b: i32) -> i32 {
[INFO] [stdout]    |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `hello`
[INFO] [stdout]   --> src/syntax/t_function.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn hello() {
[INFO] [stdout]    |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `init_len`
[INFO] [stdout]   --> src/syntax/t_function.rs:24:10
[INFO] [stdout]    |
[INFO] [stdout] 24 | const fn init_len() -> usize {
[INFO] [stdout]    |          ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `square`
[INFO] [stdout]   --> src/syntax/t_generic.rs:27:4
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn square<T: Mul + Mul<Output = T>>(x: T, y: T) -> T {
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `square1`
[INFO] [stdout]   --> src/syntax/t_generic.rs:31:4
[INFO] [stdout]    |
[INFO] [stdout] 31 | fn square1<T: Mul<T, Output = T>>(x: T, y: T) -> T {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Test`
[INFO] [stdout]  --> src/syntax/t_size.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Test<'a> {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `abs_sum`
[INFO] [stdout]   --> src/syntax/t_smart_pointer.rs:84:4
[INFO] [stdout]    |
[INFO] [stdout] 84 | fn abs_sum(ns: &[i32]) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `t_type`
[INFO] [stdout]  --> src/syntax/t_type.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn t_type() {
[INFO] [stdout]   |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 28 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y1`
[INFO] [stdout]   --> src/syntax/t_smart_pointer.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let y1 = x.borrow_mut();
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_y1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let num = 42u32;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let num: u32 = 42;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let num = 0x2A; // 十六进制
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/syntax/t_type.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let num = 0o106; // 八进制
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]   --> src/syntax/t_type.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let num = 3.55f64;
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: taking a reference to a function item does not give a function pointer
[INFO] [stdout]   --> src/syntax/t_function.rs:49:32
[INFO] [stdout]    |
[INFO] [stdout] 49 |     let addr = format!("{:p}", &fn_ptr);
[INFO] [stdout]    |                                ^^^^^^^ help: cast `hello` to obtain a function pointer: `hello as fn()`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(function_item_references)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/syntax/t_string.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |     let mut x = 'T';
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/syntax/t_type.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let mut mut_arr = [1, 2, 3];
[INFO] [stdout]    |         ----^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `pri_print_role`
[INFO] [stdout]  --> src/routes/role.rs:8:4
[INFO] [stdout]   |
[INFO] [stdout] 8 | fn pri_print_role() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]  --> src/routes/role.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | #[warn(dead_code)]
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `pri_print_user`
[INFO] [stdout]  --> src/routes/user.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn pri_print_user() {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Test`
[INFO] [stdout]  --> src/syntax/t_size.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Test<'a> {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `abs_sum`
[INFO] [stdout]   --> src/syntax/t_smart_pointer.rs:84:4
[INFO] [stdout]    |
[INFO] [stdout] 84 | fn abs_sum(ns: &[i32]) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 15 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.51s
[INFO] running `Command { std: "docker" "inspect" "a43fb2853bbbb433ae6db1e5a7cd149b2669db08031026beaf6ee21637c60945", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a43fb2853bbbb433ae6db1e5a7cd149b2669db08031026beaf6ee21637c60945", kill_on_drop: false }`
[INFO] [stdout] a43fb2853bbbb433ae6db1e5a7cd149b2669db08031026beaf6ee21637c60945