[INFO] cloning repository https://github.com/HannanKan/rust-by-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/HannanKan/rust-by-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHannanKan%2Frust-by-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHannanKan%2Frust-by-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 46b99a616bf108e48d8f0b083ed0c5ff2be5a17d
[INFO] checking HannanKan/rust-by-example against 1.95.0 for pr-155915
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHannanKan%2Frust-by-example" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/HannanKan/rust-by-example
[INFO] finished tweaking git repo https://github.com/HannanKan/rust-by-example
[INFO] tweaked toml for git repo https://github.com/HannanKan/rust-by-example written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/HannanKan/rust-by-example 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/HannanKan/rust-by-example 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] e430916a8cf8862d853c2c6cbf437a1a30bec1b4392f6faa80c17b9c6b935ad1
[INFO] running `Command { std: "docker" "start" "-a" "e430916a8cf8862d853c2c6cbf437a1a30bec1b4392f6faa80c17b9c6b935ad1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e430916a8cf8862d853c2c6cbf437a1a30bec1b4392f6faa80c17b9c6b935ad1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e430916a8cf8862d853c2c6cbf437a1a30bec1b4392f6faa80c17b9c6b935ad1", kill_on_drop: false }`
[INFO] [stdout] e430916a8cf8862d853c2c6cbf437a1a30bec1b4392f6faa80c17b9c6b935ad1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 744a836da80e29253ecabb02835faa636e20e68ef56cb9a878bb5e8615170cb1
[INFO] running `Command { std: "docker" "start" "-a" "744a836da80e29253ecabb02835faa636e20e68ef56cb9a878bb5e8615170cb1", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-by-example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking yansi v0.5.1
[INFO] [stderr]     Checking diff v0.1.13
[INFO] [stderr]     Checking pretty_assertions v1.4.0
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/16_1_derive.rs:18:16
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Seconds(i32);
[INFO] [stdout]    |        ------- ^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/bin/16_7_clone.rs:7:13
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Pair(Box<i32>, Box<i32>);
[INFO] [stdout]   |        ---- ^^^^^^^^  ^^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        fields in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing these fields
[INFO] [stdout]   = note: `Pair` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Subtract` is never constructed
[INFO] [stdout]  --> src/bin/3_2_class_alias.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | enum VeryVerboseEnumOfThingsToDoWithNumbers {
[INFO] [stdout]   |      -------------------------------------- variant in this enum
[INFO] [stdout] 3 |     Add,
[INFO] [stdout] 4 |     Subtract,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `VeryVerboseEnumOfThingsToDoWithNumbers` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `name` and `age` are never read
[INFO] [stdout]  --> src/bin/3_1_struct.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Person {
[INFO] [stdout]   |        ------ fields in this struct
[INFO] [stdout] 3 |     name: String,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout] 4 |     age: u8,
[INFO] [stdout]   |     ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Person` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `combine_vecs_explicit_return_type` is never used
[INFO] [stdout]  --> src/bin/16_6_impl_trait.rs:6:4
[INFO] [stdout]   |
[INFO] [stdout] 6 | fn combine_vecs_explicit_return_type(
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` declarations without an explicit ABI are deprecated
[INFO] [stdout]  --> src/bin/20_8_external_programming_language_interface.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | extern {
[INFO] [stdout]   | ^^^^^^ help: explicitly specify the "C" ABI: `extern "C"`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(missing_abi)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `x` is never read
[INFO] [stdout]  --> src/bin/15_4_5_lifetime_trait.rs:4:6
[INFO] [stdout]   |
[INFO] [stdout] 3 |  struct Borrowed<'a> {
[INFO] [stdout]   |         -------- field in this struct
[INFO] [stdout] 4 |      x: &'a i32,
[INFO] [stdout]   |      ^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Borrowed` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/1_2_1_debug.rs:4:18
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Structure(i32);
[INFO] [stdout]   |        --------- ^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Structure` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/1_2_1_debug.rs:8:13
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Deep(Structure);
[INFO] [stdout]   |        ---- ^^^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Deep` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `number` is never read
[INFO] [stdout]   --> src/bin/18_2_1_unpacking_option.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 11 | struct PhoneNumber {
[INFO] [stdout]    |        ----------- field in this struct
[INFO] [stdout] 12 |     area_code: Option<u8>,
[INFO] [stdout] 13 |     number: u32,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `PhoneNumber` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `quotes`
[INFO] [stdout]   --> src/bin/19_3_String.rs:95:9
[INFO] [stdout]    |
[INFO] [stdout] 95 |     let quotes = br#"You can also use "fancier" formatting, \
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_quotes`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::str::from_utf8` with an invalid literal always return an error
[INFO] [stdout]    --> src/bin/19_3_String.rs:102:11
[INFO] [stdout]     |
[INFO] [stdout]  99 |     let shift_jis = b"\x82\xe6\x82\xa8\x82\xb1\x82"; // SHIFT-JIS 编码的 "ようこそ"
[INFO] [stdout]     |                     ------------------------------- the literal was valid UTF-8 up to the 0 bytes
[INFO] [stdout] ...
[INFO] [stdout] 102 |     match str::from_utf8(shift_jis) {
[INFO] [stdout]     |           ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(invalid_from_utf8)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/16_1_derive.rs:18:16
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Seconds(i32);
[INFO] [stdout]    |        ------- ^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        field in this struct
[INFO] [stdout]    |
[INFO] [stdout]    = help: consider removing this field
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `r#try`: use the `?` operator instead
[INFO] [stdout]   --> src/bin/18_3_4_try.rs:19:24
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let first_number = r#try!(first_number_str.parse::<i32>());
[INFO] [stdout]    |                        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated macro `r#try`: use the `?` operator instead
[INFO] [stdout]   --> src/bin/18_3_4_try.rs:20:25
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let second_number = r#try!(second_number_str.parse::<i32>());
[INFO] [stdout]    |                         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/15_4_6_lifetime_constraint.rs:4:23
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Ref<'a, T: 'a>(&'a T);
[INFO] [stdout]   |        ---            ^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Ref` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `display`
[INFO] [stdout]  --> src/bin/20_3_path.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let display = path.display();
[INFO] [stdout]   |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_display`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Person` is never used
[INFO] [stdout]  --> src/bin/16_8_parent_trait.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Person {
[INFO] [stdout]   |       ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Student` is never used
[INFO] [stdout]  --> src/bin/16_8_parent_trait.rs:7:7
[INFO] [stdout]   |
[INFO] [stdout] 7 | trait Student: Person {
[INFO] [stdout]   |       ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Programmer` is never used
[INFO] [stdout]   --> src/bin/16_8_parent_trait.rs:11:7
[INFO] [stdout]    |
[INFO] [stdout] 11 | trait Programmer {
[INFO] [stdout]    |       ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `CompSciStudent` is never used
[INFO] [stdout]   --> src/bin/16_8_parent_trait.rs:17:7
[INFO] [stdout]    |
[INFO] [stdout] 17 | trait CompSciStudent: Programmer + Student {
[INFO] [stdout]    |       ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `comp_sci_student_greeting` is never used
[INFO] [stdout]   --> src/bin/16_8_parent_trait.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn comp_sci_student_greeting(student: &dyn CompSciStudent) -> String {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/bin/7_expression.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         2 * x;
[INFO] [stdout]    |         ^^^^^ the arithmetic operation produces a value
[INFO] [stdout]    |
[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] 14 |         let _ = 2 * x;
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `my_string`
[INFO] [stdout]   --> src/bin/6_1_From_to.rs:20:9
[INFO] [stdout]    |
[INFO] [stdout] 20 |     let my_string = String::from(my_str);
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_my_string`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]  --> src/bin/6_1_From_to.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Number {
[INFO] [stdout]   |        ------ field in this struct
[INFO] [stdout] 5 |     value: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Number` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused label
[INFO] [stdout]  --> src/bin/8_2_1_nestloop_tag.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |         'inner: loop {
[INFO] [stdout]   |         ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_labels)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> src/bin/16_7_clone.rs:7:13
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct Pair(Box<i32>, Box<i32>);
[INFO] [stdout]   |        ---- ^^^^^^^^  ^^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        fields in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing these fields
[INFO] [stdout]   = note: `Pair` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: irrefutable `if let` pattern
[INFO] [stdout]   --> src/bin/8_6_if_let.rs:97:8
[INFO] [stdout]    |
[INFO] [stdout] 97 |     if let Foo1::Bar = a1 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this pattern will always match, so the `if let` is useless
[INFO] [stdout]    = help: consider replacing the `if let` with a `let`
[INFO] [stdout]    = note: `#[warn(irrefutable_let_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt`
[INFO] [stdout]  --> src/bin/6_3_ToString_FromStr.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fmt;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/15_4_4_lifetime_struct.rs:4:21
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Borrowed<'a>(&'a i32);
[INFO] [stdout]   |        --------     ^^^^^^^
[INFO] [stdout]   |        |
[INFO] [stdout]   |        field in this struct
[INFO] [stdout]   |
[INFO] [stdout]   = help: consider removing this field
[INFO] [stdout]   = note: `Borrowed` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `x` and `y` are never read
[INFO] [stdout]   --> src/bin/15_4_4_lifetime_struct.rs:9:5
[INFO] [stdout]    |
[INFO] [stdout]  8 | struct NamedBorrowed<'a> {
[INFO] [stdout]    |        ------------- fields in this struct
[INFO] [stdout]  9 |     x: &'a i32,
[INFO] [stdout]    |     ^
[INFO] [stdout] 10 |     y: &'a i32,
[INFO] [stdout]    |     ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `NamedBorrowed` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/15_4_4_lifetime_struct.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     Num(i32),
[INFO] [stdout]    |     --- ^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Either` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 16 -     Num(i32),
[INFO] [stdout] 16 +     Num(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/15_4_4_lifetime_struct.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     Ref(&'a i32),
[INFO] [stdout]    |     --- ^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Either` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 17 -     Ref(&'a i32),
[INFO] [stdout] 17 +     Ref(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/bin/9_4_diverging_func.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(never_type)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable statement
[INFO] [stdout]   --> src/bin/9_4_diverging_func.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let x: ! = panic!("This call never returns.");
[INFO] [stdout]    |                ---------------------------------- any code following this expression is unreachable
[INFO] [stdout] 25 |     println!("You will never see this line!");
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unreachable statement
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> tests/21_1_unit_test.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]   --> tests/21_1_unit_test.rs:56:9
[INFO] [stdout]    |
[INFO] [stdout] 56 |     use super::*;
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/bin/9_4_diverging_func.rs:24:9
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let x: ! = panic!("This call never returns.");
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-by-example` (bin "9_4_diverging_func" test) due to 1 previous error; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "744a836da80e29253ecabb02835faa636e20e68ef56cb9a878bb5e8615170cb1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "744a836da80e29253ecabb02835faa636e20e68ef56cb9a878bb5e8615170cb1", kill_on_drop: false }`
[INFO] [stdout] 744a836da80e29253ecabb02835faa636e20e68ef56cb9a878bb5e8615170cb1
