[INFO] cloning repository https://github.com/ykwmz/leetcode-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ykwmz/leetcode-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fykwmz%2Fleetcode-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fykwmz%2Fleetcode-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0be483a8c842282db44a51e04a97490245840e4f
[INFO] checking ykwmz/leetcode-rust against try#8de4b308b608cded0ebccf658a0fc719bce87d4e for pr-89056
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fykwmz%2Fleetcode-rust" "/workspace/builds/worker-82/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-82/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ykwmz/leetcode-rust on toolchain 8de4b308b608cded0ebccf658a0fc719bce87d4e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ykwmz/leetcode-rust
[INFO] finished tweaking git repo https://github.com/ykwmz/leetcode-rust
[INFO] tweaked toml for git repo https://github.com/ykwmz/leetcode-rust written to /workspace/builds/worker-82/source/Cargo.toml
[INFO] crate git repo https://github.com/ykwmz/leetcode-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "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-82/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-82/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e8f927999ebf18ddc6aa404afbad96fba8ebb0980c2ff111310d6b22b9c166af
[INFO] running `Command { std: "docker" "start" "-a" "e8f927999ebf18ddc6aa404afbad96fba8ebb0980c2ff111310d6b22b9c166af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e8f927999ebf18ddc6aa404afbad96fba8ebb0980c2ff111310d6b22b9c166af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e8f927999ebf18ddc6aa404afbad96fba8ebb0980c2ff111310d6b22b9c166af", kill_on_drop: false }`
[INFO] [stdout] e8f927999ebf18ddc6aa404afbad96fba8ebb0980c2ff111310d6b22b9c166af
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-82/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-82/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 86223300f6b3ba0fbdca865494da7d42ce00a0ffa046cc0d725f124db9a441b2
[INFO] running `Command { std: "docker" "start" "-a" "86223300f6b3ba0fbdca865494da7d42ce00a0ffa046cc0d725f124db9a441b2", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking leetcode v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/add_two_numbers.rs:11:7
[INFO] [stdout]    |
[INFO] [stdout] 11 |    fn new(val: i32) -> Self {
[INFO] [stdout]    |       ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_two_numbers`
[INFO] [stdout]   --> src/add_two_numbers.rs:22:4
[INFO] [stdout]    |
[INFO] [stdout] 22 | fn add_two_numbers(l1: Option<Box<ListNode>>, l2: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `length_of_longest_substring`
[INFO] [stdout]  --> src/length_of_longest_substring.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn length_of_longest_substring(s: String) -> i32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `find_median_sorted_arrays`
[INFO] [stdout]  --> src/find_median_sorted_arrays.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn find_median_sorted_arrays(nums1: Vec<i32>, nums2: Vec<i32>) -> f64 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `longest_palindrome`
[INFO] [stdout]  --> src/longest_palindrome.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn longest_palindrome(s: String) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `zigzag_convert`
[INFO] [stdout]  --> src/zigzag_convert.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn zigzag_convert(s: String, num_rows: i32) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `reverse`
[INFO] [stdout]  --> src/reverse_integer.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn reverse(x: i32) -> i32 {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `find_error_nums`
[INFO] [stdout]  --> src/find_error_nums.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn find_error_nums(nums: Vec<i32>) -> Vec<i32> {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `display_table`
[INFO] [stdout]  --> src/display_table.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | pub fn display_table(orders: Vec<Vec<String>>) -> Vec<Vec<String>> {
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `count_pairs`
[INFO] [stdout]  --> src/count_pairs.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn count_pairs(deliciousness: Vec<i32>) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `num_subarrays_with_sum`
[INFO] [stdout]  --> src/num_subarrays_with_sum.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn num_subarrays_with_sum(nums: Vec<i32>, goal: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `majority_element`
[INFO] [stdout]  --> src/majority_element.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub fn majority_element(nums: Vec<i32>) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `TimeMap`
[INFO] [stdout]   --> src/time_map.rs:20:8
[INFO] [stdout]    |
[INFO] [stdout] 20 | struct TimeMap {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/time_map.rs:32:8
[INFO] [stdout]    |
[INFO] [stdout] 32 |     fn new() -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `set`
[INFO] [stdout]   --> src/time_map.rs:38:8
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn set(&mut self, key: String, value: String, timestamp: i32) {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `get`
[INFO] [stdout]   --> src/time_map.rs:45:8
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn get(&self, key: String, timestamp: i32) -> String {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `maximum_element_after_decrementing_and_rearranging`
[INFO] [stdout]   --> src/maximum_element_after_decrementing_and_rearranging.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn maximum_element_after_decrementing_and_rearranging(arr: Vec<i32>) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `search`
[INFO] [stdout]  --> src/search.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn search(nums: Vec<i32>, target: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `max_sub_array`
[INFO] [stdout]  --> src/max_sub_array.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn max_sub_array(nums: Vec<i32>) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `group_anagrams`
[INFO] [stdout]  --> src/group_anagrams.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub fn group_anagrams(strs: Vec<String>) -> Vec<Vec<String>> {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `max_frequency`
[INFO] [stdout]   --> src/max_frequency.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn max_frequency(nums: Vec<i32>, k: i32) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `min_pair_sum`
[INFO] [stdout]   --> src/min_pair_sum.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn min_pair_sum(nums: Vec<i32>) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `is_covered`
[INFO] [stdout]  --> src/is_covered.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | pub fn is_covered(ranges: Vec<Vec<i32>>, left: i32, right: i32) -> bool {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `min_operations`
[INFO] [stdout]   --> src/min_operations.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn min_operations(target: Vec<i32>, arr: Vec<i32>) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]   --> src/find_second_minimum_value.rs:17:10
[INFO] [stdout]    |
[INFO] [stdout] 17 |   pub fn new(val: i32) -> Self {
[INFO] [stdout]    |          ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `find_second_minimum_value`
[INFO] [stdout]   --> src/find_second_minimum_value.rs:30:8
[INFO] [stdout]    |
[INFO] [stdout] 30 | pub fn find_second_minimum_value(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `title_to_number`
[INFO] [stdout]   --> src/title_to_number.rs:19:8
[INFO] [stdout]    |
[INFO] [stdout] 19 | pub fn title_to_number(column_title: String) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `k_weakest_rows`
[INFO] [stdout]  --> src/k_weakest_rows.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | pub fn k_weakest_rows(mat: Vec<Vec<i32>>, k: i32) -> Vec<i32> {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `tribonacci`
[INFO] [stdout]  --> src/tribonacci.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub fn tribonacci(n: i32) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `number_of_arithmetic_slices`
[INFO] [stdout]  --> src/number_of_arithmetic_slices.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | pub fn number_of_arithmetic_slices(nums: Vec<i32>) -> i32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `longest_palindrome_subseq`
[INFO] [stdout]   --> src/longest_palindrome_subseq.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn longest_palindrome_subseq(s: String) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `check_record`
[INFO] [stdout]   --> src/check_record.rs:15:8
[INFO] [stdout]    |
[INFO] [stdout] 15 | pub fn check_record(s: String) -> bool {
[INFO] [stdout]    |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `reverse_vowels`
[INFO] [stdout]  --> src/reverse_vowels.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub fn reverse_vowels(mut s: String) -> String {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `reverse_str`
[INFO] [stdout]  --> src/reverse_str.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn reverse_str(s: String, k: i32) -> String {
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `compress`
[INFO] [stdout]   --> src/compress.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 | pub fn compress(chars: &mut Vec<char>) -> i32 {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `running_sum`
[INFO] [stdout]  --> src/running_sum.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub fn running_sum(nums: Vec<i32>) -> Vec<i32> {
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:15:17
[INFO] [stdout]    |
[INFO] [stdout] 15 |                 &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 15 |                 let _ = &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:20:17
[INFO] [stdout]    |
[INFO] [stdout] 20 |                 &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 20 |                 let _ = &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:24:17
[INFO] [stdout]    |
[INFO] [stdout] 24 |                 &s_bytes[len-l..len].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 24 |                 let _ = &s_bytes[len-l..len].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 39 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:15:17
[INFO] [stdout]    |
[INFO] [stdout] 15 |                 &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 15 |                 let _ = &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:20:17
[INFO] [stdout]    |
[INFO] [stdout] 20 |                 &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 20 |                 let _ = &s_bytes[len-l..len-l+key].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/reverse_str.rs:24:17
[INFO] [stdout]    |
[INFO] [stdout] 24 |                 &s_bytes[len-l..len].reverse();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 24 |                 let _ = &s_bytes[len-l..len].reverse();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 05s
[INFO] running `Command { std: "docker" "inspect" "86223300f6b3ba0fbdca865494da7d42ce00a0ffa046cc0d725f124db9a441b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "86223300f6b3ba0fbdca865494da7d42ce00a0ffa046cc0d725f124db9a441b2", kill_on_drop: false }`
[INFO] [stdout] 86223300f6b3ba0fbdca865494da7d42ce00a0ffa046cc0d725f124db9a441b2