[INFO] cloning repository https://github.com/aPere3/playgrust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/aPere3/playgrust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FaPere3%2Fplaygrust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FaPere3%2Fplaygrust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 13d1f4b7ee8a915dde19a6a33183494012a6f538
[INFO] testing aPere3/playgrust against 1.47.0 for beta-1.48-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FaPere3%2Fplaygrust" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/aPere3/playgrust on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/aPere3/playgrust
[INFO] finished tweaking git repo https://github.com/aPere3/playgrust
[INFO] tweaked toml for git repo https://github.com/aPere3/playgrust written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/aPere3/playgrust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5ef8811d2b538fa41200d376d87634dc484303fbc39728d8aa28997f9045171c
[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" "5ef8811d2b538fa41200d376d87634dc484303fbc39728d8aa28997f9045171c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5ef8811d2b538fa41200d376d87634dc484303fbc39728d8aa28997f9045171c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ef8811d2b538fa41200d376d87634dc484303fbc39728d8aa28997f9045171c", kill_on_drop: false }`
[INFO] [stdout] 5ef8811d2b538fa41200d376d87634dc484303fbc39728d8aa28997f9045171c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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=warn" "-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" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6196484be2651a50a87874ab33968d44d2270af3e4f812f423d6577b91d30077
[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" "6196484be2651a50a87874ab33968d44d2270af3e4f812f423d6577b91d30077", kill_on_drop: false }`
[INFO] [stderr]    Compiling playgrust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Eq` is imported redundantly
[INFO] [stdout]     --> src/rust_book/mod.rs:1082:13
[INFO] [stdout]      |
[INFO] [stdout] 1082 |         use std::cmp::Eq;
[INFO] [stdout]      |             ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:802:17
[INFO] [stdout]     |
[INFO] [stdout] 802 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:819:17
[INFO] [stdout]     |
[INFO] [stdout] 819 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:836:17
[INFO] [stdout]     |
[INFO] [stdout] 836 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> src/rust_book/mod.rs:847:17
[INFO] [stdout]     |
[INFO] [stdout] 847 |             let f: Result<&str, &str> = Result::Err("Failure").unwrap();
[INFO] [stdout]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> src/rust_book/mod.rs:850:17
[INFO] [stdout]     |
[INFO] [stdout] 850 |             let f: Result<&str, &str> = Result::Err("Failure").expect("The program failed");
[INFO] [stdout]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]     --> src/rust_book/mod.rs:1275:17
[INFO] [stdout]      |
[INFO] [stdout] 1275 |             let a = MySmartPointer(String::from("Hey guys"));
[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/rust_book/mod.rs:1317:13
[INFO] [stdout]      |
[INFO] [stdout] 1317 |         let b = List3::Cons(3, Rc::clone(&a));
[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/rust_book/mod.rs:1320:17
[INFO] [stdout]      |
[INFO] [stdout] 1320 |             let c = List3::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: value assigned to `max_index` is never read
[INFO] [stdout]    --> src/rust_book/mod.rs:958:21
[INFO] [stdout]     |
[INFO] [stdout] 958 |                 let mut max_index = 0;
[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: variable does not need to be mutable
[INFO] [stdout]     --> src/rust_book/mod.rs:1182:13
[INFO] [stdout]      |
[INFO] [stdout] 1182 |         let mut a = MyIterableArray::new();
[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: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.74s
[INFO] running `Command { std: "docker" "inspect" "6196484be2651a50a87874ab33968d44d2270af3e4f812f423d6577b91d30077", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6196484be2651a50a87874ab33968d44d2270af3e4f812f423d6577b91d30077", kill_on_drop: false }`
[INFO] [stdout] 6196484be2651a50a87874ab33968d44d2270af3e4f812f423d6577b91d30077
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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=warn" "-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" "+1.47.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f061664e2e3e25f1d1296791787a2b39139dafbc01392dfdcf7e9bed63331738
[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" "f061664e2e3e25f1d1296791787a2b39139dafbc01392dfdcf7e9bed63331738", kill_on_drop: false }`
[INFO] [stderr]    Compiling playgrust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Eq` is imported redundantly
[INFO] [stdout]     --> src/rust_book/mod.rs:1082:13
[INFO] [stdout]      |
[INFO] [stdout] 1082 |         use std::cmp::Eq;
[INFO] [stdout]      |             ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:802:17
[INFO] [stdout]     |
[INFO] [stdout] 802 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:819:17
[INFO] [stdout]     |
[INFO] [stdout] 819 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `message`
[INFO] [stdout]    --> src/rust_book/mod.rs:836:17
[INFO] [stdout]     |
[INFO] [stdout] 836 |             Err(message) => {
[INFO] [stdout]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> src/rust_book/mod.rs:847:17
[INFO] [stdout]     |
[INFO] [stdout] 847 |             let f: Result<&str, &str> = Result::Err("Failure").unwrap();
[INFO] [stdout]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]    --> src/rust_book/mod.rs:850:17
[INFO] [stdout]     |
[INFO] [stdout] 850 |             let f: Result<&str, &str> = Result::Err("Failure").expect("The program failed");
[INFO] [stdout]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]     --> src/rust_book/mod.rs:1275:17
[INFO] [stdout]      |
[INFO] [stdout] 1275 |             let a = MySmartPointer(String::from("Hey guys"));
[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/rust_book/mod.rs:1317:13
[INFO] [stdout]      |
[INFO] [stdout] 1317 |         let b = List3::Cons(3, Rc::clone(&a));
[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/rust_book/mod.rs:1320:17
[INFO] [stdout]      |
[INFO] [stdout] 1320 |             let c = List3::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: value assigned to `max_index` is never read
[INFO] [stdout]    --> src/rust_book/mod.rs:958:21
[INFO] [stdout]     |
[INFO] [stdout] 958 |                 let mut max_index = 0;
[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: variable does not need to be mutable
[INFO] [stdout]     --> src/rust_book/mod.rs:1182:13
[INFO] [stdout]      |
[INFO] [stdout] 1182 |         let mut a = MyIterableArray::new();
[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: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.64s
[INFO] running `Command { std: "docker" "inspect" "f061664e2e3e25f1d1296791787a2b39139dafbc01392dfdcf7e9bed63331738", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f061664e2e3e25f1d1296791787a2b39139dafbc01392dfdcf7e9bed63331738", kill_on_drop: false }`
[INFO] [stdout] f061664e2e3e25f1d1296791787a2b39139dafbc01392dfdcf7e9bed63331738
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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=warn" "-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" "+1.47.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 5d2a6c29a9bc9609eb6ff79ec14611f8f70131d30578f0dfb2e4b54c9d0261aa
[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" "5d2a6c29a9bc9609eb6ff79ec14611f8f70131d30578f0dfb2e4b54c9d0261aa", kill_on_drop: false }`
[INFO] [stderr] warning: the item `Eq` is imported redundantly
[INFO] [stderr]     --> src/rust_book/mod.rs:1082:13
[INFO] [stderr]      |
[INFO] [stderr] 1082 |         use std::cmp::Eq;
[INFO] [stderr]      |             ^^^^^^^^^^^^
[INFO] [stderr]      |
[INFO] [stderr]      = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `message`
[INFO] [stderr]    --> src/rust_book/mod.rs:802:17
[INFO] [stderr]     |
[INFO] [stderr] 802 |             Err(message) => {
[INFO] [stderr]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `message`
[INFO] [stderr]    --> src/rust_book/mod.rs:819:17
[INFO] [stderr]     |
[INFO] [stderr] 819 |             Err(message) => {
[INFO] [stderr]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `message`
[INFO] [stderr]    --> src/rust_book/mod.rs:836:17
[INFO] [stderr]     |
[INFO] [stderr] 836 |             Err(message) => {
[INFO] [stderr]     |                 ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_message`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]    --> src/rust_book/mod.rs:847:17
[INFO] [stderr]     |
[INFO] [stderr] 847 |             let f: Result<&str, &str> = Result::Err("Failure").unwrap();
[INFO] [stderr]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]    --> src/rust_book/mod.rs:850:17
[INFO] [stderr]     |
[INFO] [stderr] 850 |             let f: Result<&str, &str> = Result::Err("Failure").expect("The program failed");
[INFO] [stderr]     |                 ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]     --> src/rust_book/mod.rs:1275:17
[INFO] [stderr]      |
[INFO] [stderr] 1275 |             let a = MySmartPointer(String::from("Hey guys"));
[INFO] [stderr]      |                 ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]     --> src/rust_book/mod.rs:1317:13
[INFO] [stderr]      |
[INFO] [stderr] 1317 |         let b = List3::Cons(3, Rc::clone(&a));
[INFO] [stderr]      |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]     --> src/rust_book/mod.rs:1320:17
[INFO] [stderr]      |
[INFO] [stderr] 1320 |             let c = List3::Cons(4, Rc::clone(&a));
[INFO] [stderr]      |                 ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `max_index` is never read
[INFO] [stderr]    --> src/rust_book/mod.rs:958:21
[INFO] [stderr]     |
[INFO] [stderr] 958 |                 let mut max_index = 0;
[INFO] [stderr]     |                     ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]     = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]     --> src/rust_book/mod.rs:1182:13
[INFO] [stderr]      |
[INFO] [stderr] 1182 |         let mut a = MyIterableArray::new();
[INFO] [stderr]      |             ----^
[INFO] [stderr]      |             |
[INFO] [stderr]      |             help: remove this `mut`
[INFO] [stderr]      |
[INFO] [stderr]      = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 11 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/playgrust-de22d71298d30d2c
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "5d2a6c29a9bc9609eb6ff79ec14611f8f70131d30578f0dfb2e4b54c9d0261aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d2a6c29a9bc9609eb6ff79ec14611f8f70131d30578f0dfb2e4b54c9d0261aa", kill_on_drop: false }`
[INFO] [stdout] 5d2a6c29a9bc9609eb6ff79ec14611f8f70131d30578f0dfb2e4b54c9d0261aa
