[INFO] fetching crate learn_rust_bugs 0.1.0...
[INFO] building learn_rust_bugs-0.1.0 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate learn_rust_bugs 0.1.0 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate learn_rust_bugs 0.1.0 on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate learn_rust_bugs 0.1.0
[INFO] finished tweaking crates.io crate learn_rust_bugs 0.1.0
[INFO] tweaked toml for crates.io crate learn_rust_bugs 0.1.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate crates.io crate learn_rust_bugs 0.1.0 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a73c8f7a3d48b9ab5498125d77bd79b09fedf9d1687a36ca35bbca99acaac422
[INFO] running `Command { std: "docker" "start" "-a" "a73c8f7a3d48b9ab5498125d77bd79b09fedf9d1687a36ca35bbca99acaac422", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a73c8f7a3d48b9ab5498125d77bd79b09fedf9d1687a36ca35bbca99acaac422", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a73c8f7a3d48b9ab5498125d77bd79b09fedf9d1687a36ca35bbca99acaac422", kill_on_drop: false }`
[INFO] [stdout] a73c8f7a3d48b9ab5498125d77bd79b09fedf9d1687a36ca35bbca99acaac422
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6c70e2b0ffb409b3ecab0438636b74fca180b5a49653742d4c94dccd79a4574c
[INFO] running `Command { std: "docker" "start" "-a" "6c70e2b0ffb409b3ecab0438636b74fca180b5a49653742d4c94dccd79a4574c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling regex-syntax v0.6.28
[INFO] [stderr]    Compiling humantime v2.1.0
[INFO] [stderr]    Compiling termcolor v1.2.0
[INFO] [stderr]    Compiling aho-corasick v0.7.20
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling regex v1.7.1
[INFO] [stderr]    Compiling env_logger v0.9.3
[INFO] [stderr]    Compiling learn_rust_bugs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> src/locks.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> src/state_pattern/states.rs:6:27
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]   |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MyBox` is never constructed
[INFO] [stdout]  --> src/boxs/deref.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct MyBox<T>(T);
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]  --> src/boxs/deref.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | impl<T> MyBox<T> {
[INFO] [stdout]   | ---------------- associated function in this implementation
[INFO] [stdout] 6 |     fn new(x: T) -> MyBox<T> {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mybox_test` is never used
[INFO] [stdout]   --> src/boxs/deref.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn mybox_test() {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/boxs/linked_list.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]   |     ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `MessageSender` is never used
[INFO] [stdout]  --> src/boxs/refcells.rs:4:7
[INFO] [stdout]   |
[INFO] [stdout] 4 | trait MessageSender {
[INFO] [stdout]   |       ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `LimitChecker` is never constructed
[INFO] [stdout]  --> src/boxs/refcells.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct LimitChecker<'a, T>
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `set_value` are never used
[INFO] [stdout]   --> src/boxs/refcells.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 17 | / impl<'a, T> LimitChecker<'a, T>
[INFO] [stdout] 18 | | where
[INFO] [stdout] 19 | |     T: MessageSender,
[INFO] [stdout]    | |_____________________- associated items in this implementation
[INFO] [stdout] 20 |   {
[INFO] [stdout] 21 |       pub fn new(message_sender: &'a T, max: usize) -> LimitChecker<'a, T> {
[INFO] [stdout]    |              ^^^
[INFO] [stdout] ...
[INFO] [stdout] 29 |       pub fn set_value(&mut self, value: usize) {
[INFO] [stdout]    |              ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value`, `parent`, and `children` are never read
[INFO] [stdout]  --> src/boxs/trees.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Node {
[INFO] [stdout]   |            ---- fields in this struct
[INFO] [stdout] 6 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 7 |     parent: RefCell<Weak<Node>>,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 8 |     children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `tree_test` is never used
[INFO] [stdout]   --> src/boxs/trees.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn tree_test() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `state` is never read
[INFO] [stdout]  --> src/state_pattern.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Post {
[INFO] [stdout]   |        ---- field in this struct
[INFO] [stdout] 4 |     state: Option<Box<dyn states::State>>,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `add_text`, `request_review`, `approve`, and `content` are never used
[INFO] [stdout]   --> src/state_pattern.rs:9:12
[INFO] [stdout]    |
[INFO] [stdout] 8  | impl Post {
[INFO] [stdout]    | --------- associated items in this implementation
[INFO] [stdout] 9  |     pub fn new() -> Post {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 15 |     pub fn add_text(&mut self, msg: &str) {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 18 |     pub fn request_review(&mut self) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 21 |     pub fn approve(&mut self) {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 24 |     pub fn content(&self) -> &str {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `request_review`, `approve`, and `content` are never used
[INFO] [stdout]  --> src/state_pattern/states.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub trait State {
[INFO] [stdout]   |           ----- methods in this trait
[INFO] [stdout] 4 |     fn request_review(self: Box<Self>) -> Box<dyn State>;
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout] 5 |     fn approve(self: Box<Self>) -> Box<dyn State>;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 6 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: static `COUNT` is never used
[INFO] [stdout]   --> src/unsafes.rs:47:12
[INFO] [stdout]    |
[INFO] [stdout] 47 | static mut COUNT: u32 = 0;
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.21s
[INFO] running `Command { std: "docker" "inspect" "6c70e2b0ffb409b3ecab0438636b74fca180b5a49653742d4c94dccd79a4574c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c70e2b0ffb409b3ecab0438636b74fca180b5a49653742d4c94dccd79a4574c", kill_on_drop: false }`
[INFO] [stdout] 6c70e2b0ffb409b3ecab0438636b74fca180b5a49653742d4c94dccd79a4574c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 175594b34ae23217980623b6e5d16659a74e914e0f57cc8e5da2ab4a19da07b9
[INFO] running `Command { std: "docker" "start" "-a" "175594b34ae23217980623b6e5d16659a74e914e0f57cc8e5da2ab4a19da07b9", kill_on_drop: false }`
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> src/locks.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> src/state_pattern/states.rs:6:27
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]   |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MyBox` is never constructed
[INFO] [stdout]  --> src/boxs/deref.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct MyBox<T>(T);
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]  --> src/boxs/deref.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | impl<T> MyBox<T> {
[INFO] [stdout]   | ---------------- associated function in this implementation
[INFO] [stdout] 6 |     fn new(x: T) -> MyBox<T> {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mybox_test` is never used
[INFO] [stdout]   --> src/boxs/deref.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn mybox_test() {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/boxs/linked_list.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]   |     ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `MessageSender` is never used
[INFO] [stdout]  --> src/boxs/refcells.rs:4:7
[INFO] [stdout]   |
[INFO] [stdout] 4 | trait MessageSender {
[INFO] [stdout]   |       ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `LimitChecker` is never constructed
[INFO] [stdout]  --> src/boxs/refcells.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct LimitChecker<'a, T>
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `set_value` are never used
[INFO] [stdout]   --> src/boxs/refcells.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 17 | / impl<'a, T> LimitChecker<'a, T>
[INFO] [stdout] 18 | | where
[INFO] [stdout] 19 | |     T: MessageSender,
[INFO] [stdout]    | |_____________________- associated items in this implementation
[INFO] [stdout] 20 |   {
[INFO] [stdout] 21 |       pub fn new(message_sender: &'a T, max: usize) -> LimitChecker<'a, T> {
[INFO] [stdout]    |              ^^^
[INFO] [stdout] ...
[INFO] [stdout] 29 |       pub fn set_value(&mut self, value: usize) {
[INFO] [stdout]    |              ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value`, `parent`, and `children` are never read
[INFO] [stdout]  --> src/boxs/trees.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Node {
[INFO] [stdout]   |            ---- fields in this struct
[INFO] [stdout] 6 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 7 |     parent: RefCell<Weak<Node>>,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 8 |     children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `tree_test` is never used
[INFO] [stdout]   --> src/boxs/trees.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn tree_test() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `state` is never read
[INFO] [stdout]  --> src/state_pattern.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Post {
[INFO] [stdout]   |        ---- field in this struct
[INFO] [stdout] 4 |     state: Option<Box<dyn states::State>>,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `add_text`, `request_review`, `approve`, and `content` are never used
[INFO] [stdout]   --> src/state_pattern.rs:9:12
[INFO] [stdout]    |
[INFO] [stdout] 8  | impl Post {
[INFO] [stdout]    | --------- associated items in this implementation
[INFO] [stdout] 9  |     pub fn new() -> Post {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 15 |     pub fn add_text(&mut self, msg: &str) {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 18 |     pub fn request_review(&mut self) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 21 |     pub fn approve(&mut self) {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 24 |     pub fn content(&self) -> &str {
[INFO] [stdout]    |            ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling learn_rust_bugs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: methods `request_review`, `approve`, and `content` are never used
[INFO] [stdout]  --> src/state_pattern/states.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub trait State {
[INFO] [stdout]   |           ----- methods in this trait
[INFO] [stdout] 4 |     fn request_review(self: Box<Self>) -> Box<dyn State>;
[INFO] [stdout]   |        ^^^^^^^^^^^^^^
[INFO] [stdout] 5 |     fn approve(self: Box<Self>) -> Box<dyn State>;
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 6 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: static `COUNT` is never used
[INFO] [stdout]   --> src/unsafes.rs:47:12
[INFO] [stdout]    |
[INFO] [stdout] 47 | static mut COUNT: u32 = 0;
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::rc::Rc`
[INFO] [stdout]  --> src/locks.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::rc::Rc;
[INFO] [stdout]   |     ^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `point`
[INFO] [stdout]  --> tests/integration_test.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let point = Point::new(1, 2);
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_point`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> src/state_pattern/states.rs:6:27
[INFO] [stdout]   |
[INFO] [stdout] 6 |     fn content<'a>(&self, post: &'a Post) -> &'a str {
[INFO] [stdout]   |                           ^^^^ help: if this is intentional, prefix it with an underscore: `_post`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `MyBox` is never constructed
[INFO] [stdout]  --> src/boxs/deref.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct MyBox<T>(T);
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]  --> src/boxs/deref.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | impl<T> MyBox<T> {
[INFO] [stdout]   | ---------------- associated function in this implementation
[INFO] [stdout] 6 |     fn new(x: T) -> MyBox<T> {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mybox_test` is never used
[INFO] [stdout]   --> src/boxs/deref.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn mybox_test() {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/boxs/linked_list.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]   |     ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 8 |     Cons((), ()),
[INFO] [stdout]   |          ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value`, `parent`, and `children` are never read
[INFO] [stdout]  --> src/boxs/trees.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Node {
[INFO] [stdout]   |            ---- fields in this struct
[INFO] [stdout] 6 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 7 |     parent: RefCell<Weak<Node>>,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 8 |     children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `tree_test` is never used
[INFO] [stdout]   --> src/boxs/trees.rs:11:4
[INFO] [stdout]    |
[INFO] [stdout] 11 | fn tree_test() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: static `COUNT` is never used
[INFO] [stdout]   --> src/unsafes.rs:47:12
[INFO] [stdout]    |
[INFO] [stdout] 47 | static mut COUNT: u32 = 0;
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.23s
[INFO] running `Command { std: "docker" "inspect" "175594b34ae23217980623b6e5d16659a74e914e0f57cc8e5da2ab4a19da07b9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "175594b34ae23217980623b6e5d16659a74e914e0f57cc8e5da2ab4a19da07b9", kill_on_drop: false }`
[INFO] [stdout] 175594b34ae23217980623b6e5d16659a74e914e0f57cc8e5da2ab4a19da07b9