[INFO] updating cached repository https://github.com/Delorus/rust_learning
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 85e9ac89dac5dca12156acf98619a6a7add91951
[INFO] testing Delorus/rust_learning against 1.44.0 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FDelorus%2Frust_learning" "/workspace/builds/worker-12/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Delorus/rust_learning on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/Delorus/rust_learning
[INFO] finished tweaking git repo https://github.com/Delorus/rust_learning
[INFO] tweaked toml for git repo https://github.com/Delorus/rust_learning written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/Delorus/rust_learning already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b415adb9255eafd3c1de224880786adebfc85f65fa64aedb16f326ebfd43aa6b
[INFO] running `"docker" "start" "-a" "b415adb9255eafd3c1de224880786adebfc85f65fa64aedb16f326ebfd43aa6b"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling learning v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `std::rc::Rc`
[INFO] [stderr]  --> src/bin/multithreads.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use std::rc::Rc;
[INFO] [stderr]   |     ^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/bin/patterns.rs:19:10
[INFO] [stderr]    |
[INFO] [stderr] 19 |         1...5 => println!("one through five"),
[INFO] [stderr]    |          ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]    --> src/bin/patterns.rs:121:45
[INFO] [stderr]     |
[INFO] [stderr] 121 |         Message::Hello { id: id_variable @ 3...7 } => {
[INFO] [stderr]     |                                             ^^^ help: use `..=` for an inclusive range
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]    --> src/bin/patterns.rs:124:32
[INFO] [stderr]     |
[INFO] [stderr] 124 |         Message::Hello { id: 10...12 } => {
[INFO] [stderr]     |                                ^^^ help: use `..=` for an inclusive range
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `connect`
[INFO] [stderr]  --> src/bin/modules/network/mod.rs:1:4
[INFO] [stderr]   |
[INFO] [stderr] 1 | fn connect() {
[INFO] [stderr]   |    ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `use_module`
[INFO] [stderr]  --> src/bin/modules/network/mod.rs:5:4
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn use_module() {
[INFO] [stderr]   |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `connect`
[INFO] [stderr]   --> src/bin/modules/network/mod.rs:10:12
[INFO] [stderr]    |
[INFO] [stderr] 10 |     pub fn connect() {
[INFO] [stderr]    |            ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `use_pub_modules`
[INFO] [stderr]   --> src/bin/modules_main.rs:13:4
[INFO] [stderr]    |
[INFO] [stderr] 13 | fn use_pub_modules() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_new_thread`
[INFO] [stderr]   --> src/bin/multithreads.rs:10:4
[INFO] [stderr]    |
[INFO] [stderr] 10 | fn create_new_thread() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `wait_new_thread`
[INFO] [stderr]   --> src/bin/multithreads.rs:18:4
[INFO] [stderr]    |
[INFO] [stderr] 18 | fn wait_new_thread() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `move_closure_with_new_thread`
[INFO] [stderr]   --> src/bin/multithreads.rs:28:4
[INFO] [stderr]    |
[INFO] [stderr] 28 | fn move_closure_with_new_thread() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_channel`
[INFO] [stderr]   --> src/bin/multithreads.rs:38:4
[INFO] [stderr]    |
[INFO] [stderr] 38 | fn create_channel() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `sending_multiple_values_in_channels`
[INFO] [stderr]   --> src/bin/multithreads.rs:50:4
[INFO] [stderr]    |
[INFO] [stderr] 50 | fn sending_multiple_values_in_channels() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `mutex`
[INFO] [stderr]   --> src/bin/multithreads.rs:87:4
[INFO] [stderr]    |
[INFO] [stderr] 87 | fn mutex() {
[INFO] [stderr]    |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `weak_ref_cycle`
[INFO] [stderr]   --> src/bin/smart_ptr_cycle.rs:51:4
[INFO] [stderr]    |
[INFO] [stderr] 51 | fn weak_ref_cycle() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/multithreads.rs:25:5
[INFO] [stderr]    |
[INFO] [stderr] 25 |     handle.join();
[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: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/bin/multithreads.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     handle.join();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `or_match`
[INFO] [stderr]  --> src/bin/patterns.rs:5:4
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn or_match() {
[INFO] [stderr]   |    ^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `range_match`
[INFO] [stderr]   --> src/bin/patterns.rs:15:4
[INFO] [stderr]    |
[INFO] [stderr] 15 | fn range_match() {
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `destruct`
[INFO] [stderr]   --> src/bin/patterns.rs:29:4
[INFO] [stderr]    |
[INFO] [stderr] 29 | fn destruct() {
[INFO] [stderr]    |    ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Message`
[INFO] [stderr]   --> src/bin/patterns.rs:51:6
[INFO] [stderr]    |
[INFO] [stderr] 51 | enum Message {
[INFO] [stderr]    |      ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `destruct_enum`
[INFO] [stderr]   --> src/bin/patterns.rs:58:4
[INFO] [stderr]    |
[INFO] [stderr] 58 | fn destruct_enum() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `ignore_several_value`
[INFO] [stderr]   --> src/bin/patterns.rs:81:4
[INFO] [stderr]    |
[INFO] [stderr] 81 | fn ignore_several_value() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `match_guard`
[INFO] [stderr]    --> src/bin/patterns.rs:103:4
[INFO] [stderr]     |
[INFO] [stderr] 103 | fn match_guard() {
[INFO] [stderr]     |    ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `binding_in_match`
[INFO] [stderr]    --> src/bin/patterns.rs:113:4
[INFO] [stderr]     |
[INFO] [stderr] 113 | fn binding_in_match() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Guess`
[INFO] [stderr]   --> src/bin/tests.rs:60:8
[INFO] [stderr]    |
[INFO] [stderr] 60 | struct Guess {
[INFO] [stderr]    |        ^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/bin/tests.rs:65:5
[INFO] [stderr]    |
[INFO] [stderr] 65 |     pub fn new(value: u32) -> Guess {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_user`
[INFO] [stderr]   --> src/bin/structures.rs:13:4
[INFO] [stderr]    |
[INFO] [stderr] 13 | fn create_user() {
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:64:9
[INFO] [stderr]    |
[INFO] [stderr] 64 |     let c = CustomSmartPointer { data: String::from("some data") };
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_user_from_another`
[INFO] [stderr]   --> src/bin/structures.rs:28:4
[INFO] [stderr]    |
[INFO] [stderr] 28 | fn create_user_from_another() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Point`
[INFO] [stderr]   --> src/bin/structures.rs:44:8
[INFO] [stderr]    |
[INFO] [stderr] 44 | struct Point(i32, i32);
[INFO] [stderr]    |        ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:79:9
[INFO] [stderr]    |
[INFO] [stderr] 79 |     let b = Tree::Cons(3, a.clone());
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `named_tuple`
[INFO] [stderr]   --> src/bin/structures.rs:46:4
[INFO] [stderr]    |
[INFO] [stderr] 46 | fn named_tuple() {
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:82:13
[INFO] [stderr]    |
[INFO] [stderr] 82 |         let c = Tree::Cons(4, a.clone());
[INFO] [stderr]    |             ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `z`
[INFO] [stderr]   --> src/bin/data_types.rs:31:9
[INFO] [stderr]    |
[INFO] [stderr] 31 |     let z = x as u32 + y;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `mutable_var`
[INFO] [stderr]  --> src/bin/variables.rs:5:4
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn mutable_var() {
[INFO] [stderr]   |    ^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0308]: mismatched types
[INFO] [stderr]   --> src/bin/state_pattern.rs:47:41
[INFO] [stderr]    |
[INFO] [stderr] 47 |         pub fn request_preview(self) -> PendingReviewPost {
[INFO] [stderr]    |                ---------------          ^^^^^^^^^^^^^^^^^ expected struct `blog::PendingReviewPost`, found `()`
[INFO] [stderr]    |                |
[INFO] [stderr]    |                implicitly returns `()` as its body has no tail or `return` expression
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `constant`
[INFO] [stderr]   --> src/bin/variables.rs:13:4
[INFO] [stderr]    |
[INFO] [stderr] 13 | fn constant() {
[INFO] [stderr]    |    ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `const_in_func`
[INFO] [stderr]   --> src/bin/variables.rs:20:4
[INFO] [stderr]    |
[INFO] [stderr] 20 | fn const_in_func() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: constant item is never used: `MAX_POINTS`
[INFO] [stderr]   --> src/bin/variables.rs:24:1
[INFO] [stderr]    |
[INFO] [stderr] 24 | const MAX_POINTS: u32 = 200_000;
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `multiple_vars`
[INFO] [stderr]   --> src/bin/variables.rs:26:4
[INFO] [stderr]    |
[INFO] [stderr] 26 | fn multiple_vars() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `cast_to_unsigned`
[INFO] [stderr]  --> src/bin/data_types.rs:5:4
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn cast_to_unsigned() {
[INFO] [stderr]   |    ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `representation_of_number`
[INFO] [stderr]   --> src/bin/data_types.rs:10:4
[INFO] [stderr]    |
[INFO] [stderr] 10 | fn representation_of_number() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `implicit_cast`
[INFO] [stderr]   --> src/bin/data_types.rs:27:4
[INFO] [stderr]    |
[INFO] [stderr] 27 | fn implicit_cast() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `std_f32`
[INFO] [stderr]   --> src/bin/data_types.rs:34:4
[INFO] [stderr]    |
[INFO] [stderr] 34 | fn std_f32() {
[INFO] [stderr]    |    ^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `logic_op`
[INFO] [stderr]   --> src/bin/data_types.rs:71:4
[INFO] [stderr]    |
[INFO] [stderr] 71 | fn logic_op() {
[INFO] [stderr]    |    ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `chars`
[INFO] [stderr]   --> src/bin/data_types.rs:87:4
[INFO] [stderr]    |
[INFO] [stderr] 87 | fn chars() {
[INFO] [stderr]    |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `tuples`
[INFO] [stderr]   --> src/bin/data_types.rs:97:4
[INFO] [stderr]    |
[INFO] [stderr] 97 | fn tuples() {
[INFO] [stderr]    |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `box_pointer`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:11:4
[INFO] [stderr]    |
[INFO] [stderr] 11 | fn box_pointer() {
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `List`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:16:6
[INFO] [stderr]    |
[INFO] [stderr] 16 | enum List {
[INFO] [stderr]    |      ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `cons_list`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:21:4
[INFO] [stderr]    |
[INFO] [stderr] 21 | fn cons_list() -> List {
[INFO] [stderr]    |    ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `deref_smart_pointers`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:43:4
[INFO] [stderr]    |
[INFO] [stderr] 43 | fn deref_smart_pointers() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `data`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:54:5
[INFO] [stderr]    |
[INFO] [stderr] 54 |     data: String,
[INFO] [stderr]    |     ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `drop_custom_smart_ptr`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:63:4
[INFO] [stderr]    |
[INFO] [stderr] 63 | fn drop_custom_smart_ptr() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Tree`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:69:6
[INFO] [stderr]    |
[INFO] [stderr] 69 | enum Tree {
[INFO] [stderr]    |      ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `cons_tree`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:74:4
[INFO] [stderr]    |
[INFO] [stderr] 74 | fn cons_tree() {
[INFO] [stderr]    |    ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `immutably_borrows`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:88:4
[INFO] [stderr]    |
[INFO] [stderr] 88 | fn immutably_borrows(a: &i32) {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `mutably_borrows`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:92:4
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn mutably_borrows(b: &mut i32) {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `demo`
[INFO] [stderr]   --> src/bin/smart_ponter.rs:96:4
[INFO] [stderr]    |
[INFO] [stderr] 96 | fn demo(r: &RefCell<i32>) {
[INFO] [stderr]    |    ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `runtime_borrow_with_refcell`
[INFO] [stderr]    --> src/bin/smart_ponter.rs:102:4
[INFO] [stderr]     |
[INFO] [stderr] 102 | fn runtime_borrow_with_refcell() {
[INFO] [stderr]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0308`.
[INFO] [stderr] error: could not compile `learning`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] warning: method is never used: `square`
[INFO] [stderr]   --> src/bin/methods.rs:12:5
[INFO] [stderr]    |
[INFO] [stderr] 12 |     fn square(size: u32) -> Rectangle {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `longest`
[INFO] [stderr]  --> src/bin/lifetime.rs:7:4
[INFO] [stderr]   |
[INFO] [stderr] 7 | fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
[INFO] [stderr]   |    ^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `can_hold`
[INFO] [stderr]   --> src/bin/methods.rs:34:5
[INFO] [stderr]    |
[INFO] [stderr] 34 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `ImportantExcerpt`
[INFO] [stderr]   --> src/bin/lifetime.rs:26:8
[INFO] [stderr]    |
[INFO] [stderr] 26 | struct ImportantExcerpt<'a> {
[INFO] [stderr]    |        ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `lifetime_in_struct`
[INFO] [stderr]   --> src/bin/lifetime.rs:30:4
[INFO] [stderr]    |
[INFO] [stderr] 30 | fn lifetime_in_struct() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `longest_with_an_announcement`
[INFO] [stderr]   --> src/bin/lifetime.rs:42:4
[INFO] [stderr]    |
[INFO] [stderr] 42 | fn longest_with_an_announcement<'a, T>(x: &'a str, y: &'a str, ann: T) -> &'a str
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/bin/collections.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let mut v = vec![1, 2, 3, 4, 5];
[INFO] [stderr]    |         ----^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_vector`
[INFO] [stderr]  --> src/bin/collections.rs:7:4
[INFO] [stderr]   |
[INFO] [stderr] 7 | fn create_vector() {
[INFO] [stderr]   |    ^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `get_value`
[INFO] [stderr]   --> src/bin/collections.rs:16:4
[INFO] [stderr]    |
[INFO] [stderr] 16 | fn get_value() {
[INFO] [stderr]    |    ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `create_hash_map`
[INFO] [stderr]   --> src/bin/collections.rs:24:4
[INFO] [stderr]    |
[INFO] [stderr] 24 | fn create_hash_map() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `get_stats`
[INFO] [stderr]   --> src/bin/collections.rs:31:4
[INFO] [stderr]    |
[INFO] [stderr] 31 | fn get_stats() {
[INFO] [stderr]    |    ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `stats`
[INFO] [stderr]   --> src/bin/collections.rs:38:4
[INFO] [stderr]    |
[INFO] [stderr] 38 | fn stats(v: &Vec<i32>) -> (f64, i32, i32) {
[INFO] [stderr]    |    ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `total`
[INFO] [stderr]   --> src/bin/iterators.rs:10:9
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let total: i32 = v_iter.sum();
[INFO] [stderr]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `iter_terminated`
[INFO] [stderr]  --> src/bin/iterators.rs:5:4
[INFO] [stderr]   |
[INFO] [stderr] 5 | fn iter_terminated() {
[INFO] [stderr]   |    ^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `iter_adaptors`
[INFO] [stderr]   --> src/bin/iterators.rs:13:4
[INFO] [stderr]    |
[INFO] [stderr] 13 | fn iter_adaptors() {
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 11 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 5 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 15 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 3 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 8 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "b415adb9255eafd3c1de224880786adebfc85f65fa64aedb16f326ebfd43aa6b"`
[INFO] running `"docker" "rm" "-f" "b415adb9255eafd3c1de224880786adebfc85f65fa64aedb16f326ebfd43aa6b"`
[INFO] [stdout] b415adb9255eafd3c1de224880786adebfc85f65fa64aedb16f326ebfd43aa6b