[INFO] cloning repository https://github.com/xlkness/syntax
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/xlkness/syntax" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxlkness%2Fsyntax", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxlkness%2Fsyntax'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 49091f85a1d03ee73219d1d2fc3ad7a8e2531209
[INFO] checking xlkness/syntax against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxlkness%2Fsyntax" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/xlkness/syntax on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/xlkness/syntax
[INFO] finished tweaking git repo https://github.com/xlkness/syntax
[INFO] tweaked toml for git repo https://github.com/xlkness/syntax written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/xlkness/syntax already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cf6df9703fde7a6cffeca62863b58d9f6c7cd4a5a4431ec9d8be896f2665fa1f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "cf6df9703fde7a6cffeca62863b58d9f6c7cd4a5a4431ec9d8be896f2665fa1f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cf6df9703fde7a6cffeca62863b58d9f6c7cd4a5a4431ec9d8be896f2665fa1f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cf6df9703fde7a6cffeca62863b58d9f6c7cd4a5a4431ec9d8be896f2665fa1f", kill_on_drop: false }`
[INFO] [stdout] cf6df9703fde7a6cffeca62863b58d9f6c7cd4a5a4431ec9d8be896f2665fa1f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0dd33cfc13832ee55d0dfeff4d736abb1ddde736cfe3cf5985c37399feb2562c
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "0dd33cfc13832ee55d0dfeff4d736abb1ddde736cfe3cf5985c37399feb2562c", kill_on_drop: false }`
[INFO] [stderr]     Checking syntax v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::*`
[INFO] [stdout]  --> src/loop.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::*;
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::*`
[INFO] [stdout]  --> src/ownership.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::*;
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::*`
[INFO] [stdout]  --> src/loop.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::*;
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::*`
[INFO] [stdout]  --> src/ownership.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::*;
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |     let x = 5;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:34:10
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (a, b) = (1, 2);
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:34:13
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (a, b) = (1, 2);
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/main.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let c: i32 = 5;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `d` is assigned to, but never used
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let mut d = 5;
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: consider using `_d` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `d` is never read
[INFO] [stdout]   --> src/main.rs:42:5
[INFO] [stdout]    |
[INFO] [stdout] 42 |     d = 10;
[INFO] [stdout]    |     ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |     let e: i32;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/main.rs:67:9
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let f: fn(i32) -> i32 = plus_one;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f1`
[INFO] [stdout]   --> src/main.rs:69:9
[INFO] [stdout]    |
[INFO] [stdout] 69 |     let f1 = plus_one;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_f1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:72:9
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let x = true;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:73:9
[INFO] [stdout]    |
[INFO] [stdout] 73 |     let y: bool = false;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:75:9
[INFO] [stdout]    |
[INFO] [stdout] 75 |     let x = 'x';
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `two_hearts`
[INFO] [stdout]   --> src/main.rs:76:9
[INFO] [stdout]    |
[INFO] [stdout] 76 |     let two_hearts = '里';  // char is 4 bytes
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_two_hearts`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let x: i8 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:79:9
[INFO] [stdout]    |
[INFO] [stdout] 79 |     let x: i16 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let x: i32 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let x: i64 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:82:9
[INFO] [stdout]    |
[INFO] [stdout] 82 |     let x: u8 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 83 |     let x: u16 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:84:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |     let x: u32 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |     let x: u64 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let x: isize = 1;  // unfix size
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:87:9
[INFO] [stdout]    |
[INFO] [stdout] 87 |     let x: usize = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     let x: f32 = 1.0;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let x: f64 = 1.0;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:91:9
[INFO] [stdout]    |
[INFO] [stdout] 91 |     let a = [1,2,3];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut m = [1,2,3];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a_len`
[INFO] [stdout]   --> src/main.rs:94:9
[INFO] [stdout]    |
[INFO] [stdout] 94 |     let a_len = a.len();
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_a_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `complete`
[INFO] [stdout]   --> src/main.rs:98:9
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let complete = &a[..]; // a slice containing all of the elements in a
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_complete`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `middle`
[INFO] [stdout]   --> src/main.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |     let middle = &a[1..4];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_middle`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:102:9
[INFO] [stdout]     |
[INFO] [stdout] 102 |     let x = (1, "hello");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/case.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let y =
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]  --> src/ownership.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let v2 = v;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]  --> src/reference.rs:3:17
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |                 ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]  --> src/reference.rs:3:32
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |                                ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `answer`
[INFO] [stdout]   --> src/reference.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let answer = referencefoo(&v1, &v2);
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_answer`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |     let x = 5;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:34:10
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (a, b) = (1, 2);
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:34:13
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (a, b) = (1, 2);
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/main.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let c: i32 = 5;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `d` is assigned to, but never used
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let mut d = 5;
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: consider using `_d` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `d` is never read
[INFO] [stdout]   --> src/main.rs:42:5
[INFO] [stdout]    |
[INFO] [stdout] 42 |     d = 10;
[INFO] [stdout]    |     ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]    = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |     let e: i32;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/main.rs:67:9
[INFO] [stdout]    |
[INFO] [stdout] 67 |     let f: fn(i32) -> i32 = plus_one;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f1`
[INFO] [stdout]   --> src/main.rs:69:9
[INFO] [stdout]    |
[INFO] [stdout] 69 |     let f1 = plus_one;
[INFO] [stdout]    |         ^^ help: if this is intentional, prefix it with an underscore: `_f1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:72:9
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let x = true;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:73:9
[INFO] [stdout]    |
[INFO] [stdout] 73 |     let y: bool = false;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:75:9
[INFO] [stdout]    |
[INFO] [stdout] 75 |     let x = 'x';
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `two_hearts`
[INFO] [stdout]   --> src/main.rs:76:9
[INFO] [stdout]    |
[INFO] [stdout] 76 |     let two_hearts = '里';  // char is 4 bytes
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_two_hearts`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let x: i8 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:79:9
[INFO] [stdout]    |
[INFO] [stdout] 79 |     let x: i16 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:80:9
[INFO] [stdout]    |
[INFO] [stdout] 80 |     let x: i32 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let x: i64 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut m = [1,2,3];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:82:9
[INFO] [stdout]    |
[INFO] [stdout] 82 |     let x: u8 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 83 |     let x: u16 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:84:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |     let x: u32 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |     let x: u64 = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let x: isize = 1;  // unfix size
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:87:9
[INFO] [stdout]    |
[INFO] [stdout] 87 |     let x: usize = 1;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     let x: f32 = 1.0;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:89:9
[INFO] [stdout]    |
[INFO] [stdout] 89 |     let x: f64 = 1.0;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:91:9
[INFO] [stdout]    |
[INFO] [stdout] 91 |     let a = [1,2,3];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut m = [1,2,3];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a_len`
[INFO] [stdout]   --> src/main.rs:94:9
[INFO] [stdout]    |
[INFO] [stdout] 94 |     let a_len = a.len();
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_a_len`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `complete`
[INFO] [stdout]   --> src/main.rs:98:9
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let complete = &a[..]; // a slice containing all of the elements in a
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_complete`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `middle`
[INFO] [stdout]   --> src/main.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |     let middle = &a[1..4];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_middle`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]    --> src/main.rs:102:9
[INFO] [stdout]     |
[INFO] [stdout] 102 |     let x = (1, "hello");
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/case.rs:13:9
[INFO] [stdout]    |
[INFO] [stdout] 13 |     let y =
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]  --> src/ownership.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let v2 = v;
[INFO] [stdout]   |         ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v1`
[INFO] [stdout]  --> src/reference.rs:3:17
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |                 ^^ help: if this is intentional, prefix it with an underscore: `_v1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v2`
[INFO] [stdout]  --> src/reference.rs:3:32
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |                                ^^ help: if this is intentional, prefix it with an underscore: `_v2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `answer`
[INFO] [stdout]   --> src/reference.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let answer = referencefoo(&v1, &v2);
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_answer`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `case`
[INFO] [stdout]  --> src/case.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn case() {
[INFO] [stdout]   |    ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `referencefoo`
[INFO] [stdout]  --> src/reference.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `reference`
[INFO] [stdout]  --> src/reference.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn reference() {
[INFO] [stdout]   |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_one`
[INFO] [stdout]   --> src/main.rs:17:4
[INFO] [stdout]    |
[INFO] [stdout] 17 | fn add_one(x: i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `diverges`
[INFO] [stdout]   --> src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn diverges() -> ! {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut m = [1,2,3];
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 44 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `case`
[INFO] [stdout]  --> src/case.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn case() {
[INFO] [stdout]   |    ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `referencefoo`
[INFO] [stdout]  --> src/reference.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn referencefoo(v1: &Vec<i32>, v2: &Vec<i32>) -> i32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `reference`
[INFO] [stdout]  --> src/reference.rs:7:4
[INFO] [stdout]   |
[INFO] [stdout] 7 | fn reference() {
[INFO] [stdout]   |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `add_one`
[INFO] [stdout]   --> src/main.rs:17:4
[INFO] [stdout]    |
[INFO] [stdout] 17 | fn add_one(x: i32) -> i32 {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `diverges`
[INFO] [stdout]   --> src/main.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn diverges() -> ! {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 44 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.62s
[INFO] running `Command { std: "docker" "inspect" "0dd33cfc13832ee55d0dfeff4d736abb1ddde736cfe3cf5985c37399feb2562c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0dd33cfc13832ee55d0dfeff4d736abb1ddde736cfe3cf5985c37399feb2562c", kill_on_drop: false }`
[INFO] [stdout] 0dd33cfc13832ee55d0dfeff4d736abb1ddde736cfe3cf5985c37399feb2562c