[INFO] cloning repository https://github.com/mathieu-anderson/rust_variables_and_types
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mathieu-anderson/rust_variables_and_types" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmathieu-anderson%2Frust_variables_and_types", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmathieu-anderson%2Frust_variables_and_types'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] efdcd87693da19018237ecb002882e1974a099e8
[INFO] testing mathieu-anderson/rust_variables_and_types against 1.45.2 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmathieu-anderson%2Frust_variables_and_types" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mathieu-anderson/rust_variables_and_types on toolchain 1.45.2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mathieu-anderson/rust_variables_and_types
[INFO] finished tweaking git repo https://github.com/mathieu-anderson/rust_variables_and_types
[INFO] tweaked toml for git repo https://github.com/mathieu-anderson/rust_variables_and_types written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/mathieu-anderson/rust_variables_and_types already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] cceed8469bf2f25575f9e7a5687aa1ebb219ab1383dffcc424ec3712e2ae47d0
[INFO] running `Command { std: "docker" "start" "-a" "cceed8469bf2f25575f9e7a5687aa1ebb219ab1383dffcc424ec3712e2ae47d0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cceed8469bf2f25575f9e7a5687aa1ebb219ab1383dffcc424ec3712e2ae47d0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cceed8469bf2f25575f9e7a5687aa1ebb219ab1383dffcc424ec3712e2ae47d0", kill_on_drop: false }`
[INFO] [stdout] cceed8469bf2f25575f9e7a5687aa1ebb219ab1383dffcc424ec3712e2ae47d0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9218ade68c25d9e0ce7d9dd8393ea44171a3dfa2ce2d77fce0c07c3eac86d5bd
[INFO] running `Command { std: "docker" "start" "-a" "9218ade68c25d9e0ce7d9dd8393ea44171a3dfa2ce2d77fce0c07c3eac86d5bd", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_variables v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable `default_integer` is assigned to, but never used
[INFO] [stdout]   --> src/main.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let mut default_integer = 56;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: consider using `_default_integer` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `default_integer` is never read
[INFO] [stdout]   --> src/main.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     default_integer = -45;
[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: `defined_integer`
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut defined_integer: u64 = 76;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_defined_integer`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `default_float`
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let default_float = 2.0;
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_default_float`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `char_var`
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |     let char_var = 'k';
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `char_var_emoji`
[INFO] [stdout]   --> src/main.rs:46:9
[INFO] [stdout]    |
[INFO] [stdout] 46 |     let char_var_emoji = '😵';
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var_emoji`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:51:13
[INFO] [stdout]    |
[INFO] [stdout] 51 |     let (x, y, z) = tup;
[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]   --> src/main.rs:51:16
[INFO] [stdout]    |
[INFO] [stdout] 51 |     let (x, y, z) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arr`
[INFO] [stdout]   --> src/main.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     let arr = [1, 23, 67];
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `months`
[INFO] [stdout]   --> src/main.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |     let months: [&str; 3] = ["January", "February", "March"];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_months`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut defined_integer: u64 = 76;
[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 0.66s
[INFO] running `Command { std: "docker" "inspect" "9218ade68c25d9e0ce7d9dd8393ea44171a3dfa2ce2d77fce0c07c3eac86d5bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9218ade68c25d9e0ce7d9dd8393ea44171a3dfa2ce2d77fce0c07c3eac86d5bd", kill_on_drop: false }`
[INFO] [stdout] 9218ade68c25d9e0ce7d9dd8393ea44171a3dfa2ce2d77fce0c07c3eac86d5bd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 65401cdde67e6e9a55c4152198cedcb03c503fe8926e19344a76f00e2fa510ea
[INFO] running `Command { std: "docker" "start" "-a" "65401cdde67e6e9a55c4152198cedcb03c503fe8926e19344a76f00e2fa510ea", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_variables v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable `default_integer` is assigned to, but never used
[INFO] [stdout]   --> src/main.rs:34:9
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let mut default_integer = 56;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: consider using `_default_integer` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `default_integer` is never read
[INFO] [stdout]   --> src/main.rs:35:5
[INFO] [stdout]    |
[INFO] [stdout] 35 |     default_integer = -45;
[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: `defined_integer`
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut defined_integer: u64 = 76;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_defined_integer`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `default_float`
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let default_float = 2.0;
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_default_float`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `char_var`
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |     let char_var = 'k';
[INFO] [stdout]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `char_var_emoji`
[INFO] [stdout]   --> src/main.rs:46:9
[INFO] [stdout]    |
[INFO] [stdout] 46 |     let char_var_emoji = '😵';
[INFO] [stdout]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var_emoji`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:51:13
[INFO] [stdout]    |
[INFO] [stdout] 51 |     let (x, y, z) = tup;
[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]   --> src/main.rs:51:16
[INFO] [stdout]    |
[INFO] [stdout] 51 |     let (x, y, z) = tup;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `arr`
[INFO] [stdout]   --> src/main.rs:58:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     let arr = [1, 23, 67];
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_arr`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `months`
[INFO] [stdout]   --> src/main.rs:60:9
[INFO] [stdout]    |
[INFO] [stdout] 60 |     let months: [&str; 3] = ["January", "February", "March"];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_months`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut defined_integer: u64 = 76;
[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 0.41s
[INFO] running `Command { std: "docker" "inspect" "65401cdde67e6e9a55c4152198cedcb03c503fe8926e19344a76f00e2fa510ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "65401cdde67e6e9a55c4152198cedcb03c503fe8926e19344a76f00e2fa510ea", kill_on_drop: false }`
[INFO] [stdout] 65401cdde67e6e9a55c4152198cedcb03c503fe8926e19344a76f00e2fa510ea
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 4f84f97e8ba6c9a77133fa58bf7e61e70fb2435de6e7d955f27f007436bfa26c
[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" "4f84f97e8ba6c9a77133fa58bf7e61e70fb2435de6e7d955f27f007436bfa26c", kill_on_drop: false }`
[INFO] [stderr] warning: variable `default_integer` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:34:9
[INFO] [stderr]    |
[INFO] [stderr] 34 |     let mut default_integer = 56;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr]    = note: consider using `_default_integer` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `default_integer` is never read
[INFO] [stderr]   --> src/main.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     default_integer = -45;
[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: unused variable: `defined_integer`
[INFO] [stderr]   --> src/main.rs:36:9
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut defined_integer: u64 = 76;
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_defined_integer`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `default_float`
[INFO] [stderr]   --> src/main.rs:41:9
[INFO] [stderr]    |
[INFO] [stderr] 41 |     let default_float = 2.0;
[INFO] [stderr]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_default_float`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `char_var`
[INFO] [stderr]   --> src/main.rs:45:9
[INFO] [stderr]    |
[INFO] [stderr] 45 |     let char_var = 'k';
[INFO] [stderr]    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `char_var_emoji`
[INFO] [stderr]   --> src/main.rs:46:9
[INFO] [stderr]    |
[INFO] [stderr] 46 |     let char_var_emoji = '😵';
[INFO] [stderr]    |         ^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_char_var_emoji`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:51:13
[INFO] [stderr]    |
[INFO] [stderr] 51 |     let (x, y, z) = tup;
[INFO] [stderr]    |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `z`
[INFO] [stderr]   --> src/main.rs:51:16
[INFO] [stderr]    |
[INFO] [stderr] 51 |     let (x, y, z) = tup;
[INFO] [stderr]    |                ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arr`
[INFO] [stderr]   --> src/main.rs:58:9
[INFO] [stderr]    |
[INFO] [stderr] 58 |     let arr = [1, 23, 67];
[INFO] [stderr]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_arr`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `months`
[INFO] [stderr]   --> src/main.rs:60:9
[INFO] [stderr]    |
[INFO] [stderr] 60 |     let months: [&str; 3] = ["January", "February", "March"];
[INFO] [stderr]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_months`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:36:9
[INFO] [stderr]    |
[INFO] [stderr] 36 |     let mut defined_integer: u64 = 76;
[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 0.02s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/rust_variables-42bc7a6038063ecb
[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" "4f84f97e8ba6c9a77133fa58bf7e61e70fb2435de6e7d955f27f007436bfa26c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4f84f97e8ba6c9a77133fa58bf7e61e70fb2435de6e7d955f27f007436bfa26c", kill_on_drop: false }`
[INFO] [stdout] 4f84f97e8ba6c9a77133fa58bf7e61e70fb2435de6e7d955f27f007436bfa26c