[INFO] cloning repository https://github.com/dancixx/rust-course
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dancixx/rust-course" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdancixx%2Frust-course", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdancixx%2Frust-course'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ac45b3a13906280cf9deb850cea863ebb2ea63bf
[INFO] checking dancixx/rust-course against 1.95.0 for pr-155915
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdancixx%2Frust-course" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/dancixx/rust-course
[INFO] finished tweaking git repo https://github.com/dancixx/rust-course
[INFO] tweaked toml for git repo https://github.com/dancixx/rust-course written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/dancixx/rust-course on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/dancixx/rust-course 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" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded parking_lot_core v0.9.6
[INFO] [stderr]   Downloaded proc-macro2 v1.0.50
[INFO] [stderr]   Downloaded tokio v1.24.2
[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ebf25099f875f1cd69374433620352979f3b288c07c8a9a0d7ad0c7112ce2694
[INFO] running `Command { std: "docker" "start" "-a" "ebf25099f875f1cd69374433620352979f3b288c07c8a9a0d7ad0c7112ce2694", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ebf25099f875f1cd69374433620352979f3b288c07c8a9a0d7ad0c7112ce2694", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ebf25099f875f1cd69374433620352979f3b288c07c8a9a0d7ad0c7112ce2694", kill_on_drop: false }`
[INFO] [stdout] ebf25099f875f1cd69374433620352979f3b288c07c8a9a0d7ad0c7112ce2694
[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" "-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7633c13e4a9add7cd2c21c60174d7b6d89217d4b4459c9b8585e3aa855def47e
[INFO] running `Command { std: "docker" "start" "-a" "7633c13e4a9add7cd2c21c60174d7b6d89217d4b4459c9b8585e3aa855def47e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling proc-macro2 v1.0.50
[INFO] [stderr]    Compiling parking_lot_core v0.9.6
[INFO] [stderr]    Compiling syn v1.0.107
[INFO] [stderr]    Compiling tokio v1.24.2
[INFO] [stderr]    Compiling quote v1.0.23
[INFO] [stderr]     Checking num_cpus v1.15.0
[INFO] [stderr]     Checking signal-hook-registry v1.4.0
[INFO] [stderr]     Checking mio v0.8.5
[INFO] [stderr]     Checking socket2 v0.4.7
[INFO] [stderr]     Checking parking_lot v0.12.1
[INFO] [stderr]    Compiling tokio-macros v1.8.2
[INFO] [stderr]     Checking rust-course v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `Equation` is never constructed
[INFO] [stdout]  --> src/exercises/fromstr_trait_impl.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Equation {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ParseEquationError` is never constructed
[INFO] [stdout]  --> src/exercises/fromstr_trait_impl.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | struct ParseEquationError;
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `sum` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:30:4
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn sum(s: &str) -> usize {
[INFO] [stdout]    |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_equation` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn test_equation(s: &str) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:53:8
[INFO] [stdout]    |
[INFO] [stdout] 53 | pub fn run() {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_async_multithread` is never used
[INFO] [stdout]  --> src/exercises/multithreading.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn run_async_multithread() {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_sync` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub fn run_sync() {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_local_storage` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:44:8
[INFO] [stdout]    |
[INFO] [stdout] 44 | pub fn run_local_storage() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_atomic` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:72:8
[INFO] [stdout]    |
[INFO] [stdout] 72 | pub fn run_atomic() {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_tls_atomic` is never used
[INFO] [stdout]    --> src/exercises/multithreading.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 | pub fn run_tls_atomic() {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeCell` is never constructed
[INFO] [stdout]  --> src/interior_mutability.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct NodeCell<'a> {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_cell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn add_one_cell(node: &NodeCell) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 | pub fn cell() {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeRefCell` is never constructed
[INFO] [stdout]   --> src/interior_mutability.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | struct NodeRefCell<'a> {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_refcell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:52:4
[INFO] [stdout]    |
[INFO] [stdout] 52 | fn add_one_refcell(node: &NodeRefCell) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `refcell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn refcell() {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeRwLock` is never constructed
[INFO] [stdout]   --> src/interior_mutability.rs:88:8
[INFO] [stdout]    |
[INFO] [stdout] 88 | struct NodeRwLock {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_rw_lock` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:92:4
[INFO] [stdout]    |
[INFO] [stdout] 92 | fn add_one_rw_lock(node: &NodeRwLock) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rw_lock` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | pub fn rw_lock() {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeMutex` is never constructed
[INFO] [stdout]    --> src/interior_mutability.rs:147:8
[INFO] [stdout]     |
[INFO] [stdout] 147 | struct NodeMutex {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_mutex` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:151:4
[INFO] [stdout]     |
[INFO] [stdout] 151 | fn add_one_mutex(node: &NodeMutex) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mutex` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:170:8
[INFO] [stdout]     |
[INFO] [stdout] 170 | pub fn mutex() {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SUV` is never constructed
[INFO] [stdout]  --> src/dyn_trait.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct SUV;
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `WaterCapable` is never used
[INFO] [stdout]   --> src/dyn_trait.rs:13:7
[INFO] [stdout]    |
[INFO] [stdout] 13 | trait WaterCapable {
[INFO] [stdout]    |       ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Amphibious` is never used
[INFO] [stdout]   --> src/dyn_trait.rs:19:7
[INFO] [stdout]    |
[INFO] [stdout] 19 | trait Amphibious: LandCapable + WaterCapable {}
[INFO] [stdout]    |       ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Hovercraft` is never constructed
[INFO] [stdout]   --> src/dyn_trait.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Hovercraft;
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:138:5
[INFO] [stdout]     |
[INFO] [stdout] 138 |     t1.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 138 |     let _ = t1.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:139:5
[INFO] [stdout]     |
[INFO] [stdout] 139 |     t2.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 139 |     let _ = t2.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:196:5
[INFO] [stdout]     |
[INFO] [stdout] 196 |     t1.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 196 |     let _ = t1.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:197:5
[INFO] [stdout]     |
[INFO] [stdout] 197 |     t2.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 197 |     let _ = t2.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Equation` is never constructed
[INFO] [stdout]  --> src/exercises/fromstr_trait_impl.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct Equation {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ParseEquationError` is never constructed
[INFO] [stdout]  --> src/exercises/fromstr_trait_impl.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 | struct ParseEquationError;
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `sum` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:30:4
[INFO] [stdout]    |
[INFO] [stdout] 30 | fn sum(s: &str) -> usize {
[INFO] [stdout]    |    ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_equation` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn test_equation(s: &str) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run` is never used
[INFO] [stdout]   --> src/exercises/fromstr_trait_impl.rs:53:8
[INFO] [stdout]    |
[INFO] [stdout] 53 | pub fn run() {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_async_multithread` is never used
[INFO] [stdout]  --> src/exercises/multithreading.rs:6:8
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub fn run_async_multithread() {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_sync` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub fn run_sync() {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_local_storage` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:44:8
[INFO] [stdout]    |
[INFO] [stdout] 44 | pub fn run_local_storage() {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_atomic` is never used
[INFO] [stdout]   --> src/exercises/multithreading.rs:72:8
[INFO] [stdout]    |
[INFO] [stdout] 72 | pub fn run_atomic() {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `run_tls_atomic` is never used
[INFO] [stdout]    --> src/exercises/multithreading.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 | pub fn run_tls_atomic() {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeCell` is never constructed
[INFO] [stdout]  --> src/interior_mutability.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct NodeCell<'a> {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_cell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn add_one_cell(node: &NodeCell) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 | pub fn cell() {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeRefCell` is never constructed
[INFO] [stdout]   --> src/interior_mutability.rs:48:8
[INFO] [stdout]    |
[INFO] [stdout] 48 | struct NodeRefCell<'a> {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_refcell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:52:4
[INFO] [stdout]    |
[INFO] [stdout] 52 | fn add_one_refcell(node: &NodeRefCell) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `refcell` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:64:8
[INFO] [stdout]    |
[INFO] [stdout] 64 | pub fn refcell() {
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeRwLock` is never constructed
[INFO] [stdout]   --> src/interior_mutability.rs:88:8
[INFO] [stdout]    |
[INFO] [stdout] 88 | struct NodeRwLock {
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_rw_lock` is never used
[INFO] [stdout]   --> src/interior_mutability.rs:92:4
[INFO] [stdout]    |
[INFO] [stdout] 92 | fn add_one_rw_lock(node: &NodeRwLock) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rw_lock` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | pub fn rw_lock() {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `NodeMutex` is never constructed
[INFO] [stdout]    --> src/interior_mutability.rs:147:8
[INFO] [stdout]     |
[INFO] [stdout] 147 | struct NodeMutex {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `add_one_mutex` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:151:4
[INFO] [stdout]     |
[INFO] [stdout] 151 | fn add_one_mutex(node: &NodeMutex) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mutex` is never used
[INFO] [stdout]    --> src/interior_mutability.rs:170:8
[INFO] [stdout]     |
[INFO] [stdout] 170 | pub fn mutex() {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SUV` is never constructed
[INFO] [stdout]  --> src/dyn_trait.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct SUV;
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `WaterCapable` is never used
[INFO] [stdout]   --> src/dyn_trait.rs:13:7
[INFO] [stdout]    |
[INFO] [stdout] 13 | trait WaterCapable {
[INFO] [stdout]    |       ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Amphibious` is never used
[INFO] [stdout]   --> src/dyn_trait.rs:19:7
[INFO] [stdout]    |
[INFO] [stdout] 19 | trait Amphibious: LandCapable + WaterCapable {}
[INFO] [stdout]    |       ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Hovercraft` is never constructed
[INFO] [stdout]   --> src/dyn_trait.rs:21:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | struct Hovercraft;
[INFO] [stdout]    |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:138:5
[INFO] [stdout]     |
[INFO] [stdout] 138 |     t1.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 138 |     let _ = t1.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:139:5
[INFO] [stdout]     |
[INFO] [stdout] 139 |     t2.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 139 |     let _ = t2.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:196:5
[INFO] [stdout]     |
[INFO] [stdout] 196 |     t1.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 196 |     let _ = t1.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/interior_mutability.rs:197:5
[INFO] [stdout]     |
[INFO] [stdout] 197 |     t2.join();
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 197 |     let _ = t2.join();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 11.61s
[INFO] running `Command { std: "docker" "inspect" "7633c13e4a9add7cd2c21c60174d7b6d89217d4b4459c9b8585e3aa855def47e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7633c13e4a9add7cd2c21c60174d7b6d89217d4b4459c9b8585e3aa855def47e", kill_on_drop: false }`
[INFO] [stdout] 7633c13e4a9add7cd2c21c60174d7b6d89217d4b4459c9b8585e3aa855def47e
