[INFO] updating cached repository mmmpa/learning_rust_data_structure
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/mmmpa/learning_rust_data_structure
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/mmmpa/learning_rust_data_structure" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/mmmpa/learning_rust_data_structure"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/mmmpa/learning_rust_data_structure'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/mmmpa/learning_rust_data_structure" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/mmmpa/learning_rust_data_structure"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/mmmpa/learning_rust_data_structure'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 255d021cb8214c82ca6d6002070da8d59b5c87a3
[INFO] sha for GitHub repo mmmpa/learning_rust_data_structure: 255d021cb8214c82ca6d6002070da8d59b5c87a3
[INFO] validating manifest of mmmpa/learning_rust_data_structure on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of mmmpa/learning_rust_data_structure on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing mmmpa/learning_rust_data_structure
[INFO] finished frobbing mmmpa/learning_rust_data_structure
[INFO] frobbed toml for mmmpa/learning_rust_data_structure written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/mmmpa/learning_rust_data_structure/Cargo.toml
[INFO] started frobbing mmmpa/learning_rust_data_structure
[INFO] finished frobbing mmmpa/learning_rust_data_structure
[INFO] frobbed toml for mmmpa/learning_rust_data_structure written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/mmmpa/learning_rust_data_structure/Cargo.toml
[INFO] crate mmmpa/learning_rust_data_structure already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking mmmpa/learning_rust_data_structure against master#60960a260f7b5c695fd0717311d72ce62dd4eb43 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-3/master#60960a260f7b5c695fd0717311d72ce62dd4eb43:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/mmmpa/learning_rust_data_structure:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 4ab8003dd1d615bc83292a72d4f814e16c3ead94b6084ac12ea954bd5f71d965
[INFO] running `"docker" "start" "-a" "4ab8003dd1d615bc83292a72d4f814e16c3ead94b6084ac12ea954bd5f71d965"`
[INFO] [stderr]     Checking trees v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/binary_search_tree.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/parental_binary_search_tree.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/binary_search_tree.rs:62:18
[INFO] [stderr]    |
[INFO] [stderr] 62 |             Some(mut node) => {
[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: variable does not need to be mutable
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:63:18
[INFO] [stderr]    |
[INFO] [stderr] 63 |             Some(mut node) => {
[INFO] [stderr]    |                  ----^^^^
[INFO] [stderr]    |                  |
[INFO] [stderr]    |                  help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: type alias is never used: `Node`
[INFO] [stderr]  --> src/binary_search_tree.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | type Node<T> = Option<Rc<RefCell<NodeBody<T>>>>;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: type alias is never used: `Traced`
[INFO] [stderr]  --> src/binary_search_tree.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | type Traced<T> = Rc<RefCell<NodeBody<T>>>;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `BinarySearchTree`
[INFO] [stderr]   --> src/binary_search_tree.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | struct BinarySearchTree<T: Ord + Debug> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `NodeBody`
[INFO] [stderr]   --> src/binary_search_tree.rs:15:1
[INFO] [stderr]    |
[INFO] [stderr] 15 | struct NodeBody<T: Ord + Debug> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/binary_search_tree.rs:22:5
[INFO] [stderr]    |
[INFO] [stderr] 22 |     fn new(value: T) -> Node<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/binary_search_tree.rs:46:5
[INFO] [stderr]    |
[INFO] [stderr] 46 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `insert`
[INFO] [stderr]   --> src/binary_search_tree.rs:53:5
[INFO] [stderr]    |
[INFO] [stderr] 53 |     pub fn insert(&mut self, v: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `insert_support`
[INFO] [stderr]   --> src/binary_search_tree.rs:59:5
[INFO] [stderr]    |
[INFO] [stderr] 59 |     fn insert_support(&mut self, root: Node<T>, v: T) -> Node<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `trace`
[INFO] [stderr]   --> src/binary_search_tree.rs:76:5
[INFO] [stderr]    |
[INFO] [stderr] 76 |     fn trace(&self) -> Vec<Traced<T>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `trace_support`
[INFO] [stderr]   --> src/binary_search_tree.rs:82:5
[INFO] [stderr]    |
[INFO] [stderr] 82 |     fn trace_support(&self, root: &Node<T>, result: &mut Vec<Traced<T>>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: type alias is never used: `Node`
[INFO] [stderr]  --> src/parental_binary_search_tree.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | type Node<T> = Option<Rc<RefCell<NodeBody<T>>>>;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: type alias is never used: `Traced`
[INFO] [stderr]  --> src/parental_binary_search_tree.rs:7:1
[INFO] [stderr]   |
[INFO] [stderr] 7 | type Traced<T> = Rc<RefCell<NodeBody<T>>>;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `BinarySearchTree`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | struct BinarySearchTree<T: Ord + Debug> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `NodeBody`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:15:1
[INFO] [stderr]    |
[INFO] [stderr] 15 | struct NodeBody<T: Ord + Debug> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:23:5
[INFO] [stderr]    |
[INFO] [stderr] 23 |     fn new(value: T, parent: Node<T>) -> Node<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:47:5
[INFO] [stderr]    |
[INFO] [stderr] 47 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `insert`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:54:5
[INFO] [stderr]    |
[INFO] [stderr] 54 |     pub fn insert(&mut self, v: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `insert_support`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:60:5
[INFO] [stderr]    |
[INFO] [stderr] 60 |     fn insert_support(&mut self, root: Node<T>, v: T, p: Node<T>) -> Node<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `trace`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:78:5
[INFO] [stderr]    |
[INFO] [stderr] 78 |     fn trace(&self) -> Vec<Traced<T>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `trace_support`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:84:5
[INFO] [stderr]    |
[INFO] [stderr] 84 |     fn trace_support(&self, root: &Node<T>, result: &mut Vec<Traced<T>>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `TestContainer`
[INFO] [stderr]   --> src/main.rs:12:1
[INFO] [stderr]    |
[INFO] [stderr] 12 | struct TestContainer {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `TestRc`
[INFO] [stderr]   --> src/main.rs:17:1
[INFO] [stderr]    |
[INFO] [stderr] 17 | struct TestRc {
[INFO] [stderr]    | ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Test`
[INFO] [stderr]   --> src/main.rs:22:1
[INFO] [stderr]    |
[INFO] [stderr] 22 | struct Test {
[INFO] [stderr]    | ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/binary_search_tree.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `core::borrow::BorrowMut`
[INFO] [stderr]  --> src/parental_binary_search_tree.rs:4:5
[INFO] [stderr]   |
[INFO] [stderr] 4 | use core::borrow::BorrowMut;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:40:9
[INFO] [stderr]    |
[INFO] [stderr] 40 |     let mut raw_box = Rc::new(Test { value: None });
[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: variable does not need to be mutable
[INFO] [stderr]   --> src/binary_search_tree.rs:62:18
[INFO] [stderr]    |
[INFO] [stderr] 62 |             Some(mut node) => {
[INFO] [stderr]    |                  ----^^^^
[INFO] [stderr]    |                  |
[INFO] [stderr]    |                  help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:63:18
[INFO] [stderr]    |
[INFO] [stderr] 63 |             Some(mut node) => {
[INFO] [stderr]    |                  ----^^^^
[INFO] [stderr]    |                  |
[INFO] [stderr]    |                  help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `parent`
[INFO] [stderr]   --> src/parental_binary_search_tree.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 |     parent: Node<T>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `TestRc`
[INFO] [stderr]   --> src/main.rs:17:1
[INFO] [stderr]    |
[INFO] [stderr] 17 | struct TestRc {
[INFO] [stderr]    | ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.86s
[INFO] running `"docker" "inspect" "4ab8003dd1d615bc83292a72d4f814e16c3ead94b6084ac12ea954bd5f71d965"`
[INFO] running `"docker" "rm" "-f" "4ab8003dd1d615bc83292a72d4f814e16c3ead94b6084ac12ea954bd5f71d965"`
[INFO] [stdout] 4ab8003dd1d615bc83292a72d4f814e16c3ead94b6084ac12ea954bd5f71d965