Dec 19 09:35:21.801 INFO checking ryota-sakamoto/rust_study against master#d99a320cba42f661aebfa1293b7b2ec3603dda75 for pr-56955
Dec 19 09:35:21.801 INFO running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-56955/worker-6/master#d99a320cba42f661aebfa1293b7b2ec3603dda75:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/gh/ryota-sakamoto/rust_study:/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" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "check" "--frozen" "--all" "--all-targets"`
Dec 19 09:35:22.296 INFO [stdout] 1b362c5da18139c0d2da18c3e18246dcdb2d229370b4ef80ccbc7e3f2207081f
Dec 19 09:35:22.298 INFO running `"docker" "start" "-a" "1b362c5da18139c0d2da18c3e18246dcdb2d229370b4ef80ccbc7e3f2207081f"`
Dec 19 09:35:24.072 INFO [stderr]     Checking rust_test v0.1.0 (/opt/crater/workdir)
Dec 19 09:35:24.376 INFO [stderr] warning: unused macro definition
Dec 19 09:35:24.376 INFO [stderr]   --> src/list.rs:53:1
Dec 19 09:35:24.376 INFO [stderr]    |
Dec 19 09:35:24.376 INFO [stderr] 53 | / macro_rules! list {
Dec 19 09:35:24.376 INFO [stderr] 54 | |     ($($n: expr),*) => {
Dec 19 09:35:24.376 INFO [stderr] 55 | |         {
Dec 19 09:35:24.376 INFO [stderr] 56 | |             let mut list = List::empty_list();
Dec 19 09:35:24.376 INFO [stderr] ...  |
Dec 19 09:35:24.376 INFO [stderr] 74 | |     };
Dec 19 09:35:24.376 INFO [stderr] 75 | | }
Dec 19 09:35:24.376 INFO [stderr]    | |_^
Dec 19 09:35:24.376 INFO [stderr]    |
Dec 19 09:35:24.376 INFO [stderr]    = note: #[warn(unused_macros)] on by default
Dec 19 09:35:24.376 INFO [stderr] 
Dec 19 09:35:24.378 INFO [stderr] warning: unused macro definition
Dec 19 09:35:24.378 INFO [stderr]   --> src/list.rs:53:1
Dec 19 09:35:24.378 INFO [stderr]    |
Dec 19 09:35:24.378 INFO [stderr] 53 | / macro_rules! list {
Dec 19 09:35:24.378 INFO [stderr] 54 | |     ($($n: expr),*) => {
Dec 19 09:35:24.378 INFO [stderr] 55 | |         {
Dec 19 09:35:24.378 INFO [stderr] 56 | |             let mut list = List::empty_list();
Dec 19 09:35:24.378 INFO [stderr] ...  |
Dec 19 09:35:24.378 INFO [stderr] 74 | |     };
Dec 19 09:35:24.378 INFO [stderr] 75 | | }
Dec 19 09:35:24.378 INFO [stderr]    | |_^
Dec 19 09:35:24.378 INFO [stderr]    |
Dec 19 09:35:24.378 INFO [stderr]    = note: #[warn(unused_macros)] on by default
Dec 19 09:35:24.378 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: function is never used: `call`
Dec 19 09:35:24.456 INFO [stderr]  --> src/module.rs:1:1
Dec 19 09:35:24.456 INFO [stderr]   |
Dec 19 09:35:24.456 INFO [stderr] 1 | pub fn call() {
Dec 19 09:35:24.456 INFO [stderr]   | ^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr]   |
Dec 19 09:35:24.456 INFO [stderr]   = note: #[warn(dead_code)] on by default
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: enum is never used: `List`
Dec 19 09:35:24.456 INFO [stderr]  --> src/list.rs:4:1
Dec 19 09:35:24.456 INFO [stderr]   |
Dec 19 09:35:24.456 INFO [stderr] 4 | pub enum List<T: Debug> {
Dec 19 09:35:24.456 INFO [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: method is never used: `empty_list`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:13:5
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 13 |     pub fn empty_list() -> List<T> {
Dec 19 09:35:24.456 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: method is never used: `prepend`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:17:5
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 17 |     pub fn prepend(self, t: T) -> Self {
Dec 19 09:35:24.456 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: method is never used: `head`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:24:5
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 24 |     pub fn head(&self) -> &T {
Dec 19 09:35:24.456 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: method is never used: `last`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:31:5
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 31 |     pub fn last(&self) -> &T {
Dec 19 09:35:24.456 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: method is never used: `is_empty`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:44:5
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 44 |     fn is_empty(&self) -> bool {
Dec 19 09:35:24.456 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.456 INFO [stderr] warning: function is never used: `tailrec`
Dec 19 09:35:24.456 INFO [stderr]   --> src/list.rs:87:1
Dec 19 09:35:24.456 INFO [stderr]    |
Dec 19 09:35:24.456 INFO [stderr] 87 | fn tailrec<T: Debug>(list: &List<T>) {
Dec 19 09:35:24.456 INFO [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.456 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: function is never used: `call`
Dec 19 09:35:24.469 INFO [stderr]  --> src/module.rs:1:1
Dec 19 09:35:24.469 INFO [stderr]   |
Dec 19 09:35:24.469 INFO [stderr] 1 | pub fn call() {
Dec 19 09:35:24.469 INFO [stderr]   | ^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr]   |
Dec 19 09:35:24.469 INFO [stderr]   = note: #[warn(dead_code)] on by default
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: enum is never used: `List`
Dec 19 09:35:24.469 INFO [stderr]  --> src/list.rs:4:1
Dec 19 09:35:24.469 INFO [stderr]   |
Dec 19 09:35:24.469 INFO [stderr] 4 | pub enum List<T: Debug> {
Dec 19 09:35:24.469 INFO [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: method is never used: `empty_list`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:13:5
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 13 |     pub fn empty_list() -> List<T> {
Dec 19 09:35:24.469 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: method is never used: `prepend`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:17:5
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 17 |     pub fn prepend(self, t: T) -> Self {
Dec 19 09:35:24.469 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: method is never used: `head`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:24:5
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 24 |     pub fn head(&self) -> &T {
Dec 19 09:35:24.469 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: method is never used: `last`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:31:5
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 31 |     pub fn last(&self) -> &T {
Dec 19 09:35:24.469 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: method is never used: `is_empty`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:44:5
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 44 |     fn is_empty(&self) -> bool {
Dec 19 09:35:24.469 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: function is never used: `tailrec`
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:87:1
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 87 | fn tailrec<T: Debug>(list: &List<T>) {
Dec 19 09:35:24.469 INFO [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr] 
Dec 19 09:35:24.469 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.469 INFO [stderr]   --> src/list.rs:27:26
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.469 INFO [stderr] 27 |             &List::List {head: ref head, tail: _} => head,
Dec 19 09:35:24.469 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.469 INFO [stderr]    |                          |
Dec 19 09:35:24.469 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.469 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr]    = note: #[warn(non_shorthand_field_patterns)] on by default
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:34:26
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                          |
Dec 19 09:35:24.470 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:34:42
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                                          -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                                          |
Dec 19 09:35:24.470 INFO [stderr]    |                                          help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:27:26
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 27 |             &List::List {head: ref head, tail: _} => head,
Dec 19 09:35:24.470 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                          |
Dec 19 09:35:24.470 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr]    = note: #[warn(non_shorthand_field_patterns)] on by default
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:90:22
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                      -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                      |
Dec 19 09:35:24.470 INFO [stderr]    |                      help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:34:26
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                          |
Dec 19 09:35:24.470 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:90:38
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:34:42
Dec 19 09:35:24.470 INFO [stderr]    |                                      -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                                      |
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr]    |                                      help: remove this
Dec 19 09:35:24.470 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                                          -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                                          |
Dec 19 09:35:24.470 INFO [stderr]    |                                          help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:90:22
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                      -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                      |
Dec 19 09:35:24.470 INFO [stderr]    |                      help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.470 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.470 INFO [stderr]   --> src/list.rs:90:38
Dec 19 09:35:24.470 INFO [stderr]    |
Dec 19 09:35:24.470 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.470 INFO [stderr]    |                                      -----^^^^^^^^^
Dec 19 09:35:24.470 INFO [stderr]    |                                      |
Dec 19 09:35:24.470 INFO [stderr]    |                                      help: remove this
Dec 19 09:35:24.470 INFO [stderr] 
Dec 19 09:35:24.696 INFO [stderr] warning: unused macro definition
Dec 19 09:35:24.696 INFO [stderr]   --> src/list.rs:53:1
Dec 19 09:35:24.696 INFO [stderr]    |
Dec 19 09:35:24.696 INFO [stderr] 53 | / macro_rules! list {
Dec 19 09:35:24.696 INFO [stderr] 54 | |     ($($n: expr),*) => {
Dec 19 09:35:24.696 INFO [stderr] 55 | |         {
Dec 19 09:35:24.696 INFO [stderr] 56 | |             let mut list = List::empty_list();
Dec 19 09:35:24.696 INFO [stderr] ...  |
Dec 19 09:35:24.696 INFO [stderr] 74 | |     };
Dec 19 09:35:24.696 INFO [stderr] 75 | | }
Dec 19 09:35:24.696 INFO [stderr]    | |_^
Dec 19 09:35:24.696 INFO [stderr]    |
Dec 19 09:35:24.696 INFO [stderr]    = note: #[warn(unused_macros)] on by default
Dec 19 09:35:24.696 INFO [stderr] 
Dec 19 09:35:24.814 INFO [stderr] warning: unused macro definition
Dec 19 09:35:24.814 INFO [stderr]   --> src/list.rs:53:1
Dec 19 09:35:24.814 INFO [stderr]    |
Dec 19 09:35:24.814 INFO [stderr] 53 | / macro_rules! list {
Dec 19 09:35:24.814 INFO [stderr] 54 | |     ($($n: expr),*) => {
Dec 19 09:35:24.814 INFO [stderr] 55 | |         {
Dec 19 09:35:24.814 INFO [stderr] 56 | |             let mut list = List::empty_list();
Dec 19 09:35:24.814 INFO [stderr] ...  |
Dec 19 09:35:24.814 INFO [stderr] 74 | |     };
Dec 19 09:35:24.815 INFO [stderr] 75 | | }
Dec 19 09:35:24.815 INFO [stderr]    | |_^
Dec 19 09:35:24.815 INFO [stderr]    |
Dec 19 09:35:24.815 INFO [stderr]    = note: #[warn(unused_macros)] on by default
Dec 19 09:35:24.815 INFO [stderr] 
Dec 19 09:35:24.866 INFO [stderr] warning: method is never used: `head`
Dec 19 09:35:24.867 INFO [stderr]   --> src/list.rs:24:5
Dec 19 09:35:24.867 INFO [stderr]    |
Dec 19 09:35:24.867 INFO [stderr] 24 |     pub fn head(&self) -> &T {
Dec 19 09:35:24.867 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.867 INFO [stderr]    |
Dec 19 09:35:24.867 INFO [stderr]    = note: #[warn(dead_code)] on by default
Dec 19 09:35:24.867 INFO [stderr] 
Dec 19 09:35:24.867 INFO [stderr] warning: method is never used: `last`
Dec 19 09:35:24.867 INFO [stderr]   --> src/list.rs:31:5
Dec 19 09:35:24.867 INFO [stderr]    |
Dec 19 09:35:24.867 INFO [stderr] 31 |     pub fn last(&self) -> &T {
Dec 19 09:35:24.867 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.867 INFO [stderr] 
Dec 19 09:35:24.867 INFO [stderr] warning: method is never used: `is_empty`
Dec 19 09:35:24.867 INFO [stderr]   --> src/list.rs:44:5
Dec 19 09:35:24.867 INFO [stderr]    |
Dec 19 09:35:24.867 INFO [stderr] 44 |     fn is_empty(&self) -> bool {
Dec 19 09:35:24.867 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.867 INFO [stderr] 
Dec 19 09:35:24.910 INFO [stderr] warning: function is never used: `tailrec`
Dec 19 09:35:24.910 INFO [stderr]   --> src/list.rs:87:1
Dec 19 09:35:24.910 INFO [stderr]    |
Dec 19 09:35:24.910 INFO [stderr] 87 | fn tailrec<T: Debug>(list: &List<T>) {
Dec 19 09:35:24.910 INFO [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.910 INFO [stderr] 
Dec 19 09:35:24.910 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.910 INFO [stderr]   --> src/list.rs:27:26
Dec 19 09:35:24.910 INFO [stderr]    |
Dec 19 09:35:24.910 INFO [stderr] 27 |             &List::List {head: ref head, tail: _} => head,
Dec 19 09:35:24.910 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.910 INFO [stderr]    |                          |
Dec 19 09:35:24.910 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.910 INFO [stderr]    |
Dec 19 09:35:24.910 INFO [stderr]    = note: #[warn(non_shorthand_field_patterns)] on by default
Dec 19 09:35:24.910 INFO [stderr] 
Dec 19 09:35:24.910 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.910 INFO [stderr]   --> src/list.rs:34:26
Dec 19 09:35:24.910 INFO [stderr]    |
Dec 19 09:35:24.910 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.910 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.910 INFO [stderr]    |                          |
Dec 19 09:35:24.910 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.910 INFO [stderr] 
Dec 19 09:35:24.911 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.911 INFO [stderr]   --> src/list.rs:34:42
Dec 19 09:35:24.911 INFO [stderr]    |
Dec 19 09:35:24.911 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.911 INFO [stderr]    |                                          -----^^^^^^^^^
Dec 19 09:35:24.911 INFO [stderr]    |                                          |
Dec 19 09:35:24.911 INFO [stderr]    |                                          help: remove this
Dec 19 09:35:24.911 INFO [stderr] 
Dec 19 09:35:24.911 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.911 INFO [stderr]   --> src/list.rs:90:22
Dec 19 09:35:24.911 INFO [stderr]    |
Dec 19 09:35:24.911 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.911 INFO [stderr]    |                      -----^^^^^^^^^
Dec 19 09:35:24.911 INFO [stderr]    |                      |
Dec 19 09:35:24.911 INFO [stderr]    |                      help: remove this
Dec 19 09:35:24.911 INFO [stderr] 
Dec 19 09:35:24.911 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.911 INFO [stderr]   --> src/list.rs:90:38
Dec 19 09:35:24.911 INFO [stderr]    |
Dec 19 09:35:24.911 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.911 INFO [stderr]    |                                      -----^^^^^^^^^
Dec 19 09:35:24.911 INFO [stderr]    |                                      |
Dec 19 09:35:24.911 INFO [stderr]    |                                      help: remove this
Dec 19 09:35:24.911 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: method is never used: `head`
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:24:5
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 24 |     pub fn head(&self) -> &T {
Dec 19 09:35:24.956 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr]    = note: #[warn(dead_code)] on by default
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: method is never used: `last`
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:31:5
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 31 |     pub fn last(&self) -> &T {
Dec 19 09:35:24.956 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: method is never used: `is_empty`
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:44:5
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 44 |     fn is_empty(&self) -> bool {
Dec 19 09:35:24.956 INFO [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: function is never used: `tailrec`
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:87:1
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 87 | fn tailrec<T: Debug>(list: &List<T>) {
Dec 19 09:35:24.956 INFO [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:27:26
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 27 |             &List::List {head: ref head, tail: _} => head,
Dec 19 09:35:24.956 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr]    |                          |
Dec 19 09:35:24.956 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr]    = note: #[warn(non_shorthand_field_patterns)] on by default
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:34:26
Dec 19 09:35:24.956 INFO [stderr]    |
Dec 19 09:35:24.956 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.956 INFO [stderr]    |                          -----^^^^^^^^^
Dec 19 09:35:24.956 INFO [stderr]    |                          |
Dec 19 09:35:24.956 INFO [stderr]    |                          help: remove this
Dec 19 09:35:24.956 INFO [stderr] 
Dec 19 09:35:24.956 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.956 INFO [stderr]   --> src/list.rs:34:42
Dec 19 09:35:24.957 INFO [stderr]    |
Dec 19 09:35:24.957 INFO [stderr] 34 |             &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.957 INFO [stderr]    |                                          -----^^^^^^^^^
Dec 19 09:35:24.957 INFO [stderr]    |                                          |
Dec 19 09:35:24.957 INFO [stderr]    |                                          help: remove this
Dec 19 09:35:24.957 INFO [stderr] 
Dec 19 09:35:24.968 INFO [stderr] warning: the `head:` in this pattern is redundant
Dec 19 09:35:24.968 INFO [stderr]   --> src/list.rs:90:22
Dec 19 09:35:24.968 INFO [stderr]    |
Dec 19 09:35:24.968 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.968 INFO [stderr]    |                      -----^^^^^^^^^
Dec 19 09:35:24.968 INFO [stderr]    |                      |
Dec 19 09:35:24.968 INFO [stderr]    |                      help: remove this
Dec 19 09:35:24.968 INFO [stderr] 
Dec 19 09:35:24.968 INFO [stderr] warning: the `tail:` in this pattern is redundant
Dec 19 09:35:24.968 INFO [stderr]   --> src/list.rs:90:38
Dec 19 09:35:24.968 INFO [stderr]    |
Dec 19 09:35:24.968 INFO [stderr] 90 |         &List::List {head: ref head, tail: ref tail} => {
Dec 19 09:35:24.968 INFO [stderr]    |                                      -----^^^^^^^^^
Dec 19 09:35:24.968 INFO [stderr]    |                                      |
Dec 19 09:35:24.968 INFO [stderr]    |                                      help: remove this
Dec 19 09:35:24.968 INFO [stderr] 
Dec 19 09:35:25.024 INFO [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.01s
Dec 19 09:35:25.977 INFO running `"docker" "inspect" "1b362c5da18139c0d2da18c3e18246dcdb2d229370b4ef80ccbc7e3f2207081f"`
Dec 19 09:35:26.349 INFO running `"docker" "rm" "-f" "1b362c5da18139c0d2da18c3e18246dcdb2d229370b4ef80ccbc7e3f2207081f"`
Dec 19 09:35:26.624 INFO [stdout] 1b362c5da18139c0d2da18c3e18246dcdb2d229370b4ef80ccbc7e3f2207081f