[INFO] cloning repository https://github.com/sumit03guha/rust-learnings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sumit03guha/rust-learnings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsumit03guha%2Frust-learnings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsumit03guha%2Frust-learnings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fdf791ec8f54e8682682ba7818e16862db9f0b27
[INFO] testing sumit03guha/rust-learnings against try#b83b707f97d809763b7861afa7638871f3339a33 for pr-145838-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsumit03guha%2Frust-learnings" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/sumit03guha/rust-learnings
[INFO] finished tweaking git repo https://github.com/sumit03guha/rust-learnings
[INFO] tweaked toml for git repo https://github.com/sumit03guha/rust-learnings written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/sumit03guha/rust-learnings on toolchain b83b707f97d809763b7861afa7638871f3339a33
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b83b707f97d809763b7861afa7638871f3339a33" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/sumit03guha/rust-learnings 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" "+b83b707f97d809763b7861afa7638871f3339a33" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+b83b707f97d809763b7861afa7638871f3339a33" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3e90db2d611ecbda52f09fdcce566b7eaad5db7d370b3e0607b37a25cc58505b
[INFO] running `Command { std: "docker" "start" "-a" "3e90db2d611ecbda52f09fdcce566b7eaad5db7d370b3e0607b37a25cc58505b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3e90db2d611ecbda52f09fdcce566b7eaad5db7d370b3e0607b37a25cc58505b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3e90db2d611ecbda52f09fdcce566b7eaad5db7d370b3e0607b37a25cc58505b", kill_on_drop: false }`
[INFO] [stdout] 3e90db2d611ecbda52f09fdcce566b7eaad5db7d370b3e0607b37a25cc58505b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+b83b707f97d809763b7861afa7638871f3339a33" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f6118e927fc7025871e64073b07ab723b5caa6f6e88cc8d2908fc0f47b18d665
[INFO] running `Command { std: "docker" "start" "-a" "f6118e927fc7025871e64073b07ab723b5caa6f6e88cc8d2908fc0f47b18d665", kill_on_drop: false }`
[INFO] [stderr]    Compiling mutex v0.1.0 (/opt/rustwide/workdir/mutex)
[INFO] [stderr]    Compiling rusty v0.1.0 (/opt/rustwide/workdir/rusty)
[INFO] [stderr]    Compiling closures v0.1.0 (/opt/rustwide/workdir/closures)
[INFO] [stderr]    Compiling adv_types v0.1.0 (/opt/rustwide/workdir/adv_types)
[INFO] [stderr]    Compiling iterator v0.1.0 (/opt/rustwide/workdir/iterator)
[INFO] [stderr]    Compiling threads v0.1.0 (/opt/rustwide/workdir/threads)
[INFO] [stderr]    Compiling blog_post_sans_oops v0.1.0 (/opt/rustwide/workdir/blog_post_sans_oops)
[INFO] [stderr]    Compiling cons_list v0.1.0 (/opt/rustwide/workdir/cons_list)
[INFO] [stderr]    Compiling adv_traits v0.1.0 (/opt/rustwide/workdir/adv_traits)
[INFO] [stderr]    Compiling gui v0.1.0 (/opt/rustwide/workdir/gui)
[INFO] [stderr]    Compiling weak_refs v0.1.0 (/opt/rustwide/workdir/weak_refs)
[INFO] [stderr]    Compiling playground v0.1.0 (/opt/rustwide/workdir/playground)
[INFO] [stderr]    Compiling boks v0.1.0 (/opt/rustwide/workdir/boks)
[INFO] [stderr]    Compiling blog_post v0.1.0 (/opt/rustwide/workdir/blog_post)
[INFO] [stderr]    Compiling lurklurk v0.1.0 (/opt/rustwide/workdir/lurklurk)
[INFO] [stderr]    Compiling not_so_safe v0.1.0 (/opt/rustwide/workdir/not_so_safe)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> adv_types/src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let x: &str = "hello";
[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] warning: struct `MyBox` is never constructed
[INFO] [stdout]  --> rusty/src/main.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | struct MyBox(i32);
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Cons` and `Nil`
[INFO] [stdout]  --> boks/src/main.rs:6:19
[INFO] [stdout]   |
[INFO] [stdout] 6 | use crate::List::{Cons, Nil};
[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 variable: `v2`
[INFO] [stdout]   --> iterator/src/main.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let v2 = v1_iter.map(closure).collect::<Vec<i32>>();
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `name` is never read
[INFO] [stdout]  --> rusty/src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Person {
[INFO] [stdout]   |        ------ field in this struct
[INFO] [stdout] 6 |     name:String,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `get_name` is never used
[INFO] [stdout]   --> rusty/src/main.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | trait Getter {
[INFO] [stdout]    |       ------ method in this trait
[INFO] [stdout] ...
[INFO] [stdout] 13 |     fn get_name(&self) -> &str;
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `set_name` is never used
[INFO] [stdout]   --> rusty/src/main.rs:19:8
[INFO] [stdout]    |
[INFO] [stdout] 16 | trait Setter {
[INFO] [stdout]    |       ------ method in this trait
[INFO] [stdout] ...
[INFO] [stdout] 19 |     fn set_name(&mut self, name: &str);
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Colour` is never used
[INFO] [stdout]   --> rusty/src/main.rs:42:6
[INFO] [stdout]    |
[INFO] [stdout] 42 | enum Colour {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_colour` is never used
[INFO] [stdout]   --> rusty/src/main.rs:48:4
[INFO] [stdout]    |
[INFO] [stdout] 48 | fn print_colour(input_colour: &Colour) {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> iterator/src/main.rs:2:9
[INFO] [stdout]   |
[INFO] [stdout] 2 |     let mut array_of_str: Vec<String> = vec![String::from("a"),String::from("b"),String::from("c")];
[INFO] [stdout]   |         ----^^^^^^^^^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> iterator/src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let mut array_iter = array_of_str.iter();
[INFO] [stdout]   |         ----^^^^^^^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `List` is never used
[INFO] [stdout]  --> boks/src/main.rs:1:6
[INFO] [stdout]   |
[INFO] [stdout] 1 | enum List {
[INFO] [stdout]   |      ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `first`
[INFO] [stdout]   --> playground/src/main.rs:32:9
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let first = &mut data;
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_first`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `second`
[INFO] [stdout]   --> playground/src/main.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let second = &mut data;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_second`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `score`
[INFO] [stdout]   --> playground/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let score = &scores[0];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_score`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> playground/src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |     let y = &x;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> playground/src/main.rs:46:9
[INFO] [stdout]    |
[INFO] [stdout] 46 |     let z = &mut x;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> iterator/src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |         drop(element)
[INFO] [stdout]    |         ^^^^^-------^
[INFO] [stdout]    |              |
[INFO] [stdout]    |              argument has type `&String`
[INFO] [stdout]    |
[INFO] [stdout]    = note: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> closures/src/main.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let a = String::from("s");
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]  --> closures/src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Rectangle {
[INFO] [stdout]   |        --------- field in this struct
[INFO] [stdout] 3 |     width: u32,
[INFO] [stdout] 4 |     height: u32,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Rectangle` 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: `screens`
[INFO] [stdout]   --> gui/src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let screens = Screens {
[INFO] [stdout]    |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_screens`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `collections` is never read
[INFO] [stdout]   --> gui/src/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout]  9 | struct Screens<T: Draw> {
[INFO] [stdout]    |        ------- field in this struct
[INFO] [stdout] 10 |     collections: Vec<T>,
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `draw` is never used
[INFO] [stdout]   --> gui/src/main.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | / impl<T> Screens<T>
[INFO] [stdout] 14 | | where
[INFO] [stdout] 15 | |     T: Draw,
[INFO] [stdout]    | |____________- method in this implementation
[INFO] [stdout] 16 |   {
[INFO] [stdout] 17 |       fn draw(&self) {
[INFO] [stdout]    |          ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `width`, `height`, and `label` are never read
[INFO] [stdout]   --> gui/src/main.rs:42:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     struct Button {
[INFO] [stdout]    |            ------ fields in this struct
[INFO] [stdout] 42 |         width: u32,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 43 |         height: u32,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout] 44 |         label: String,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `width`, `height`, and `label` are never read
[INFO] [stdout]   --> gui/src/main.rs:48:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |     struct InputBox {
[INFO] [stdout]    |            -------- fields in this struct
[INFO] [stdout] 48 |         width: u32,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 49 |         height: u32,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout] 50 |         label: String,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `upgraded`
[INFO] [stdout]   --> weak_refs/src/main.rs:32:13
[INFO] [stdout]    |
[INFO] [stdout] 32 |         let upgraded = leaf.parent.borrow().upgrade();
[INFO] [stdout]    |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_upgraded`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `back_strong`
[INFO] [stdout]   --> weak_refs/src/main.rs:51:9
[INFO] [stdout]    |
[INFO] [stdout] 51 |     let back_strong = weak_pointer.borrow().upgrade().unwrap();
[INFO] [stdout]    |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_back_strong`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `cons_list`
[INFO] [stdout]  --> cons_list/src/main.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let cons_list = Cons(1, Box::new(Cons(2, Box::new(Cons(3, Box::new(Nil))))));
[INFO] [stdout]   |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_cons_list`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `children` are never read
[INFO] [stdout]  --> weak_refs/src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | struct Node {
[INFO] [stdout]   |        ---- fields in this struct
[INFO] [stdout] 5 |     value:i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 6 |     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]   = 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]  --> cons_list/src/main.rs:2:10
[INFO] [stdout]   |
[INFO] [stdout] 2 |     Cons(i32, Box<ConsList>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[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] 2 -     Cons(i32, Box<ConsList>),
[INFO] [stdout] 2 +     Cons((), ()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary `unsafe` block
[INFO] [stdout]  --> not_so_safe/src/main.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     unsafe {
[INFO] [stdout]   |     ^^^^^^ unnecessary `unsafe` block
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_unsafe)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `post`
[INFO] [stdout]  --> blog_post/src/main.rs:5:27
[INFO] [stdout]   |
[INFO] [stdout] 5 |     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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `reject` is never used
[INFO] [stdout]  --> blog_post/src/main.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait State {
[INFO] [stdout]   |       ----- method in this trait
[INFO] [stdout] ...
[INFO] [stdout] 4 |     fn reject(self: Box<Self>) -> Box<dyn State>;
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rct v0.1.0 (/opt/rustwide/workdir/rct)
[INFO] [stderr]    Compiling smart_pointers v0.1.0 (/opt/rustwide/workdir/smart_pointers)
[INFO] [stderr]    Compiling ref_cell v0.1.0 (/opt/rustwide/workdir/ref_cell)
[INFO] [stderr]    Compiling weak v0.1.0 (/opt/rustwide/workdir/weak)
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> rct/src/main.rs:17:13
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let b = Cons(3, Rc::clone(&a));
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> rct/src/main.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let c = Cons(4, Rc::clone(&a));
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]  --> rct/src/main.rs:5:10
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Cons(i32, Rc<List>),
[INFO] [stdout]   |     ---- ^^^  ^^^^^^^^
[INFO] [stdout]   |     |
[INFO] [stdout]   |     fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[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] 5 -     Cons(i32, Rc<List>),
[INFO] [stdout] 5 +     Cons((), ()),
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `borrow::BorrowMut`
[INFO] [stdout]  --> weak/src/main.rs:1:27
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{rc::{Rc, Weak}, borrow::BorrowMut, cell::RefCell};
[INFO] [stdout]   |                           ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling channels v0.1.0 (/opt/rustwide/workdir/channels)
[INFO] [stderr]    Compiling drop v0.1.0 (/opt/rustwide/workdir/drop)
[INFO] [stderr]    Compiling play v0.1.0 (/opt/rustwide/workdir/play)
[INFO] [stdout] warning: unused variable: `msg`
[INFO] [stdout]  --> ref_cell/src/lib.rs:2:20
[INFO] [stdout]   |
[INFO] [stdout] 2 |     fn send(&self, msg: &str) {}
[INFO] [stdout]   |                    ^^^ help: if this is intentional, prefix it with an underscore: `_msg`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Messenger` is never used
[INFO] [stdout]  --> ref_cell/src/lib.rs:1:7
[INFO] [stdout]   |
[INFO] [stdout] 1 | trait Messenger {
[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 `Limiter` is never constructed
[INFO] [stdout]  --> ref_cell/src/lib.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Limiter<'a, T: Messenger> {
[INFO] [stdout]   |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new` and `set_value` are never used
[INFO] [stdout]   --> ref_cell/src/lib.rs:15:8
[INFO] [stdout]    |
[INFO] [stdout] 11 | / impl<'a, T> Limiter<'a, T>
[INFO] [stdout] 12 | | where 
[INFO] [stdout] 13 | |     T: Messenger
[INFO] [stdout]    | |________________- associated items in this implementation
[INFO] [stdout] 14 |   {
[INFO] [stdout] 15 |       fn new(messenger: &T, max_value: usize) -> Limiter<T> {
[INFO] [stdout]    |          ^^^
[INFO] [stdout] ...
[INFO] [stdout] 23 |       fn set_value(&self, value: usize) {
[INFO] [stdout]    |          ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]   --> ref_cell/src/lib.rs:15:23
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn new(messenger: &T, max_value: usize) -> Limiter<T> {
[INFO] [stdout]    |                       ^^                       ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]    |                       |
[INFO] [stdout]    |                       the lifetime is elided here
[INFO] [stdout]    |
[INFO] [stdout]    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]    |
[INFO] [stdout] 15 |     fn new(messenger: &T, max_value: usize) -> Limiter<'_, T> {
[INFO] [stdout]    |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rc_ref`
[INFO] [stdout]   --> drop/src/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let rc_ref = &_reference_to_another_mydrop;
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_rc_ref`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `add_to_it`
[INFO] [stdout]   --> play/src/main.rs:32:9
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let add_to_it = |x: i32| -> i32 {
[INFO] [stdout]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_add_to_it`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]  --> play/src/main.rs:2:8
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Shoe {
[INFO] [stdout]   |        ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_size` is never used
[INFO] [stdout]  --> play/src/main.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn shoes_in_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `abs` found for struct `Rc<{integer}>` in the current scope
[INFO] [stdout]   --> smart_pointers/src/main.rs:66:21
[INFO] [stdout]    |
[INFO] [stdout] 66 |     let val2 = *val.abs();
[INFO] [stdout]    |                     ^^^ method not found in `Rc<{integer}>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0599`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `smart_pointers` (bin "smart_pointers") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "f6118e927fc7025871e64073b07ab723b5caa6f6e88cc8d2908fc0f47b18d665", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f6118e927fc7025871e64073b07ab723b5caa6f6e88cc8d2908fc0f47b18d665", kill_on_drop: false }`
[INFO] [stdout] f6118e927fc7025871e64073b07ab723b5caa6f6e88cc8d2908fc0f47b18d665