[INFO] updating cached repository https://github.com/sanevillain/rust_intro
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fd8a87eac661a6748b7abf2a65346421e1ce013a
[INFO] testing sanevillain/rust_intro against try#03a1ea71b075ab964b5278bc6e74cd6c52c36ee0 for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsanevillain%2Frust_intro" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sanevillain/rust_intro on toolchain 03a1ea71b075ab964b5278bc6e74cd6c52c36ee0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sanevillain/rust_intro
[INFO] finished tweaking git repo https://github.com/sanevillain/rust_intro
[INFO] tweaked toml for git repo https://github.com/sanevillain/rust_intro written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/sanevillain/rust_intro already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6d7122d94f8580f57825c39004a21bf2865054574097376f58cb45c9e753bc1b
[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" "6d7122d94f8580f57825c39004a21bf2865054574097376f58cb45c9e753bc1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6d7122d94f8580f57825c39004a21bf2865054574097376f58cb45c9e753bc1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d7122d94f8580f57825c39004a21bf2865054574097376f58cb45c9e753bc1b", kill_on_drop: false }`
[INFO] [stdout] 6d7122d94f8580f57825c39004a21bf2865054574097376f58cb45c9e753bc1b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=forbid" "-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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3cafd902257d87e62e55492e2717bb7b421256aee513b8541e6903b7de5e34d9
[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" "3cafd902257d87e62e55492e2717bb7b421256aee513b8541e6903b7de5e34d9", kill_on_drop: false }`
[INFO] [stderr]    Compiling play_ground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     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: variable `y` is assigned to, but never used
[INFO] [stdout]  --> src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let mut y = 10;
[INFO] [stdout]   |         ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: consider using `_y` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `y` is never read
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     y += 1;
[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: `a`
[INFO] [stdout]   --> src/main.rs:15:9
[INFO] [stdout]    |
[INFO] [stdout] 15 |     let a = 1 + 21;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> src/main.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let s = 30 - 20;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let m = 5 * 10;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]   --> src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let d = 4 / 6;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]   --> src/main.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let r = 49 % 2;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let t: bool = true;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/main.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let f: bool = false;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let c: char = 'z';
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/main.rs:32:10
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:32:13
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[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:32:16
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x1`
[INFO] [stdout]   --> src/main.rs:35:16
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let (_, _, x1) = t;
[INFO] [stdout]    |                ^^ help: if this is intentional, prefix it with an underscore: `_x1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let a = [1, 2, 3, 4, 5, 6, 7, 8];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.51s
[INFO] running `Command { std: "docker" "inspect" "3cafd902257d87e62e55492e2717bb7b421256aee513b8541e6903b7de5e34d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3cafd902257d87e62e55492e2717bb7b421256aee513b8541e6903b7de5e34d9", kill_on_drop: false }`
[INFO] [stdout] 3cafd902257d87e62e55492e2717bb7b421256aee513b8541e6903b7de5e34d9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=forbid" "-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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d9a3948ba8e2f4d5cf6da51fa00480dd92c8d3092846292898d5aa1f85b7d50f
[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" "d9a3948ba8e2f4d5cf6da51fa00480dd92c8d3092846292898d5aa1f85b7d50f", kill_on_drop: false }`
[INFO] [stderr]    Compiling play_ground v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     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: variable `y` is assigned to, but never used
[INFO] [stdout]  --> src/main.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let mut y = 10;
[INFO] [stdout]   |         ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: consider using `_y` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `y` is never read
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     y += 1;
[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: `a`
[INFO] [stdout]   --> src/main.rs:15:9
[INFO] [stdout]    |
[INFO] [stdout] 15 |     let a = 1 + 21;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s`
[INFO] [stdout]   --> src/main.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let s = 30 - 20;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `m`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let m = 5 * 10;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `d`
[INFO] [stdout]   --> src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let d = 4 / 6;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]   --> src/main.rs:19:9
[INFO] [stdout]    |
[INFO] [stdout] 19 |     let r = 49 % 2;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let t: bool = true;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]   --> src/main.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let f: bool = false;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let c: char = 'z';
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `z`
[INFO] [stdout]   --> src/main.rs:32:10
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]   --> src/main.rs:32:13
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[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:32:16
[INFO] [stdout]    |
[INFO] [stdout] 32 |     let (z, y, x) = t;
[INFO] [stdout]    |                ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x1`
[INFO] [stdout]   --> src/main.rs:35:16
[INFO] [stdout]    |
[INFO] [stdout] 35 |     let (_, _, x1) = t;
[INFO] [stdout]    |                ^^ help: if this is intentional, prefix it with an underscore: `_x1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |     let a = [1, 2, 3, 4, 5, 6, 7, 8];
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.46s
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "d9a3948ba8e2f4d5cf6da51fa00480dd92c8d3092846292898d5aa1f85b7d50f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d9a3948ba8e2f4d5cf6da51fa00480dd92c8d3092846292898d5aa1f85b7d50f", kill_on_drop: false }`
[INFO] [stdout] d9a3948ba8e2f4d5cf6da51fa00480dd92c8d3092846292898d5aa1f85b7d50f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=forbid" "-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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e2361e2a33faac1372a9b34f1de2f577dfb2c876d55e6eaf4cc75a205c36bac2
[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" "e2361e2a33faac1372a9b34f1de2f577dfb2c876d55e6eaf4cc75a205c36bac2", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stdout] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stdout] running 0 tests
[INFO] [stderr]  --> src/main.rs:3:9
[INFO] [stdout] 
[INFO] [stderr]   |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stderr] 3 |     let x = 5;
[INFO] [stdout] 
[INFO] [stderr]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable `y` is assigned to, but never used
[INFO] [stderr]  --> src/main.rs:6:9
[INFO] [stderr]   |
[INFO] [stderr] 6 |     let mut y = 10;
[INFO] [stderr]   |         ^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: consider using `_y` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `y` is never read
[INFO] [stderr]  --> src/main.rs:7:5
[INFO] [stderr]   |
[INFO] [stderr] 7 |     y += 1;
[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: `a`
[INFO] [stderr]   --> src/main.rs:15:9
[INFO] [stderr]    |
[INFO] [stderr] 15 |     let a = 1 + 21;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s`
[INFO] [stderr]   --> src/main.rs:16:9
[INFO] [stderr]    |
[INFO] [stderr] 16 |     let s = 30 - 20;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_s`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `m`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let m = 5 * 10;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_m`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `d`
[INFO] [stderr]   --> src/main.rs:18:9
[INFO] [stderr]    |
[INFO] [stderr] 18 |     let d = 4 / 6;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_d`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r`
[INFO] [stderr]   --> src/main.rs:19:9
[INFO] [stderr]    |
[INFO] [stderr] 19 |     let r = 49 % 2;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `t`
[INFO] [stderr]   --> src/main.rs:22:9
[INFO] [stderr]    |
[INFO] [stderr] 22 |     let t: bool = true;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]   --> src/main.rs:23:9
[INFO] [stderr]    |
[INFO] [stderr] 23 |     let f: bool = false;
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]   --> src/main.rs:26:9
[INFO] [stderr]    |
[INFO] [stderr] 26 |     let c: char = 'z';
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `z`
[INFO] [stderr]   --> src/main.rs:32:10
[INFO] [stderr]    |
[INFO] [stderr] 32 |     let (z, y, x) = t;
[INFO] [stderr]    |          ^ help: if this is intentional, prefix it with an underscore: `_z`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:32:13
[INFO] [stderr]    |
[INFO] [stderr] 32 |     let (z, y, x) = t;
[INFO] [stderr]    |             ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:32:16
[INFO] [stderr]    |
[INFO] [stderr] 32 |     let (z, y, x) = t;
[INFO] [stderr]    |                ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x1`
[INFO] [stderr]   --> src/main.rs:35:16
[INFO] [stderr]    |
[INFO] [stderr] 35 |     let (_, _, x1) = t;
[INFO] [stderr]    |                ^^ help: if this is intentional, prefix it with an underscore: `_x1`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]   --> src/main.rs:41:9
[INFO] [stderr]    |
[INFO] [stderr] 41 |     let a = [1, 2, 3, 4, 5, 6, 7, 8];
[INFO] [stderr]    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stderr] 
[INFO] [stderr] warning: 16 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 4.57s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/play_ground-7750cf1ec1484915
[INFO] running `Command { std: "docker" "inspect" "e2361e2a33faac1372a9b34f1de2f577dfb2c876d55e6eaf4cc75a205c36bac2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2361e2a33faac1372a9b34f1de2f577dfb2c876d55e6eaf4cc75a205c36bac2", kill_on_drop: false }`
[INFO] [stdout] e2361e2a33faac1372a9b34f1de2f577dfb2c876d55e6eaf4cc75a205c36bac2