[INFO] fetching crate apres 0.3.4...
[INFO] checking apres-0.3.4 against try#47af3d0de9d26c7deba4cfb203b710cc3f764e91 for pr-130443
[INFO] extracting crate apres 0.3.4 into /workspace/builds/worker-0-tc2/source
[INFO] validating manifest of crates.io crate apres 0.3.4 on toolchain 47af3d0de9d26c7deba4cfb203b710cc3f764e91
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+47af3d0de9d26c7deba4cfb203b710cc3f764e91" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate apres 0.3.4
[INFO] finished tweaking crates.io crate apres 0.3.4
[INFO] tweaked toml for crates.io crate apres 0.3.4 written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+47af3d0de9d26c7deba4cfb203b710cc3f764e91" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+47af3d0de9d26c7deba4cfb203b710cc3f764e91" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+47af3d0de9d26c7deba4cfb203b710cc3f764e91" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0d79a70f1e989482a78d1fac4a3c74f7f8882140a5d327e0305a8a81e236578d
[INFO] running `Command { std: "docker" "start" "-a" "0d79a70f1e989482a78d1fac4a3c74f7f8882140a5d327e0305a8a81e236578d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0d79a70f1e989482a78d1fac4a3c74f7f8882140a5d327e0305a8a81e236578d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0d79a70f1e989482a78d1fac4a3c74f7f8882140a5d327e0305a8a81e236578d", kill_on_drop: false }`
[INFO] [stdout] 0d79a70f1e989482a78d1fac4a3c74f7f8882140a5d327e0305a8a81e236578d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+47af3d0de9d26c7deba4cfb203b710cc3f764e91" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 24ca8d3baa0be194226e8c67bcd1c9631965b20e768ef4d4c1876bcc12026ade
[INFO] running `Command { std: "docker" "start" "-a" "24ca8d3baa0be194226e8c67bcd1c9631965b20e768ef4d4c1876bcc12026ade", kill_on_drop: false }`
[INFO] [stderr]     Checking apres v0.3.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `min`
[INFO] [stdout]  --> src/lib.rs:3:21
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::cmp::{max, min};
[INFO] [stdout]   |                     ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::MIDIEvent::*`
[INFO] [stdout]  --> src/tests.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use super::MIDIEvent::*;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout] help: if this is a test module, consider adding a `#[cfg(test)]` to the containing module
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub mod tests;
[INFO] [stdout]   | ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Duration` and `Instant`
[INFO] [stdout]  --> src/controller.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::time::{Duration, Instant};
[INFO] [stdout]   |                 ^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `min`
[INFO] [stdout]  --> src/lib.rs:3:21
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::cmp::{max, min};
[INFO] [stdout]   |                     ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Duration` and `Instant`
[INFO] [stdout]  --> src/controller.rs:4:17
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::time::{Duration, Instant};
[INFO] [stdout]   |                 ^^^^^^^^  ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/controller.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Err(e) => {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/controller.rs:71:13
[INFO] [stdout]    |
[INFO] [stdout] 71 |         let n: u32;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `varlength`
[INFO] [stdout]   --> src/controller.rs:72:13
[INFO] [stdout]    |
[INFO] [stdout] 72 |         let varlength: u64;
[INFO] [stdout]    |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_varlength`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]    --> src/lib.rs:733:13
[INFO] [stdout]     |
[INFO] [stdout] 733 |         let n: u32;
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]     --> src/lib.rs:1286:17
[INFO] [stdout]      |
[INFO] [stdout] 1286 |             Err(e) => {
[INFO] [stdout]      |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `smpte` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1315:17
[INFO] [stdout]      |
[INFO] [stdout] 1315 |         let mut smpte: u32;
[INFO] [stdout]      |                 ^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_smpte` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `tpf` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1316:17
[INFO] [stdout]      |
[INFO] [stdout] 1316 |         let mut tpf: u32;
[INFO] [stdout]      |                 ^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_tpf` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `found_header` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1321:17
[INFO] [stdout]      |
[INFO] [stdout] 1321 |         let mut found_header = false;
[INFO] [stdout]      |                 ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_found_header` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `smpte` is never read
[INFO] [stdout]     --> src/lib.rs:1341:21
[INFO] [stdout]      |
[INFO] [stdout] 1341 |                     smpte = (((divword & 0x7F00) >> 8) as i8) as u32;
[INFO] [stdout]      |                     ^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout]      = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `tpf` is never read
[INFO] [stdout]     --> src/lib.rs:1342:21
[INFO] [stdout]      |
[INFO] [stdout] 1342 |                     tpf = divword & 0x00FF;
[INFO] [stdout]      |                     ^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `found_header` is never read
[INFO] [stdout]     --> src/lib.rs:1349:17
[INFO] [stdout]      |
[INFO] [stdout] 1349 |                 found_header = true;
[INFO] [stdout]      |                 ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `bytes`
[INFO] [stdout]     --> src/lib.rs:1364:58
[INFO] [stdout]      |
[INFO] [stdout] 1364 |                         Err(ApresError::UnknownMetaEvent(bytes)) => {
[INFO] [stdout]      |                                                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_bytes`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `bytes`
[INFO] [stdout]     --> src/lib.rs:1367:57
[INFO] [stdout]      |
[INFO] [stdout] 1367 |                         Err(ApresError::IllegibleString(bytes)) => {
[INFO] [stdout]      |                                                         ^^^^^ help: if this is intentional, prefix it with an underscore: `_bytes`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]     --> src/lib.rs:1385:13
[INFO] [stdout]      |
[INFO] [stdout] 1385 |         let n: u32;
[INFO] [stdout]      |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `varlength`
[INFO] [stdout]     --> src/lib.rs:1386:13
[INFO] [stdout]      |
[INFO] [stdout] 1386 |         let varlength: u64;
[INFO] [stdout]      |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_varlength`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]     --> src/lib.rs:1468:17
[INFO] [stdout]      |
[INFO] [stdout] 1468 |             Err(e) => {
[INFO] [stdout]      |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `track`
[INFO] [stdout]     --> src/lib.rs:1524:36
[INFO] [stdout]      |
[INFO] [stdout] 1524 |     pub fn get_track_length(&self, track: usize) -> usize {
[INFO] [stdout]      |                                    ^^^^^ help: if this is intentional, prefix it with an underscore: `_track`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]     --> src/lib.rs:1672:24
[INFO] [stdout]      |
[INFO] [stdout] 1672 | fn build_key_signature(mut mi: u8, mut sf: u8) -> MIDIEvent {
[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: variable does not need to be mutable
[INFO] [stdout]     --> src/lib.rs:1672:36
[INFO] [stdout]      |
[INFO] [stdout] 1672 | fn build_key_signature(mut mi: u8, mut sf: u8) -> MIDIEvent {
[INFO] [stdout]      |                                    ----^^
[INFO] [stdout]      |                                    |
[INFO] [stdout]      |                                    help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]     --> src/lib.rs:1280:17
[INFO] [stdout]      |
[INFO] [stdout] 1280 |                 file.read(&mut buffer);
[INFO] [stdout]      |                 ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]      = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1280 |                 let _ = file.read(&mut buffer);
[INFO] [stdout]      |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]     --> src/lib.rs:1466:17
[INFO] [stdout]      |
[INFO] [stdout] 1466 |                 file.write_all(bytes.as_slice());
[INFO] [stdout]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1466 |                 let _ = file.write_all(bytes.as_slice());
[INFO] [stdout]      |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/tests.rs:245:13
[INFO] [stdout]     |
[INFO] [stdout] 245 |         let mut event = ChannelPrefix(i as u8);
[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: `bpm`
[INFO] [stdout]    --> src/tests.rs:261:10
[INFO] [stdout]     |
[INFO] [stdout] 261 |     for (bpm, expected_uspqn) in test_cases_bpm.iter() {
[INFO] [stdout]     |          ^^^ help: if this is intentional, prefix it with an underscore: `_bpm`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/tests.rs:262:13
[INFO] [stdout]     |
[INFO] [stdout] 262 |         let mut event = SetTempo(*expected_uspqn);
[INFO] [stdout]     |             ----^^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 24 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]   --> src/controller.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Err(e) => {
[INFO] [stdout]    |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]   --> src/controller.rs:71:13
[INFO] [stdout]    |
[INFO] [stdout] 71 |         let n: u32;
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `varlength`
[INFO] [stdout]   --> src/controller.rs:72:13
[INFO] [stdout]    |
[INFO] [stdout] 72 |         let varlength: u64;
[INFO] [stdout]    |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_varlength`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]    --> src/lib.rs:733:13
[INFO] [stdout]     |
[INFO] [stdout] 733 |         let n: u32;
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]     --> src/lib.rs:1286:17
[INFO] [stdout]      |
[INFO] [stdout] 1286 |             Err(e) => {
[INFO] [stdout]      |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `smpte` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1315:17
[INFO] [stdout]      |
[INFO] [stdout] 1315 |         let mut smpte: u32;
[INFO] [stdout]      |                 ^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_smpte` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `tpf` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1316:17
[INFO] [stdout]      |
[INFO] [stdout] 1316 |         let mut tpf: u32;
[INFO] [stdout]      |                 ^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_tpf` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `found_header` is assigned to, but never used
[INFO] [stdout]     --> src/lib.rs:1321:17
[INFO] [stdout]      |
[INFO] [stdout] 1321 |         let mut found_header = false;
[INFO] [stdout]      |                 ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: consider using `_found_header` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `smpte` is never read
[INFO] [stdout]     --> src/lib.rs:1341:21
[INFO] [stdout]      |
[INFO] [stdout] 1341 |                     smpte = (((divword & 0x7F00) >> 8) as i8) as u32;
[INFO] [stdout]      |                     ^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout]      = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `tpf` is never read
[INFO] [stdout]     --> src/lib.rs:1342:21
[INFO] [stdout]      |
[INFO] [stdout] 1342 |                     tpf = divword & 0x00FF;
[INFO] [stdout]      |                     ^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `found_header` is never read
[INFO] [stdout]     --> src/lib.rs:1349:17
[INFO] [stdout]      |
[INFO] [stdout] 1349 |                 found_header = true;
[INFO] [stdout]      |                 ^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `bytes`
[INFO] [stdout]     --> src/lib.rs:1364:58
[INFO] [stdout]      |
[INFO] [stdout] 1364 |                         Err(ApresError::UnknownMetaEvent(bytes)) => {
[INFO] [stdout]      |                                                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_bytes`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `bytes`
[INFO] [stdout]     --> src/lib.rs:1367:57
[INFO] [stdout]      |
[INFO] [stdout] 1367 |                         Err(ApresError::IllegibleString(bytes)) => {
[INFO] [stdout]      |                                                         ^^^^^ help: if this is intentional, prefix it with an underscore: `_bytes`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n`
[INFO] [stdout]     --> src/lib.rs:1385:13
[INFO] [stdout]      |
[INFO] [stdout] 1385 |         let n: u32;
[INFO] [stdout]      |             ^ help: if this is intentional, prefix it with an underscore: `_n`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `varlength`
[INFO] [stdout]     --> src/lib.rs:1386:13
[INFO] [stdout]      |
[INFO] [stdout] 1386 |         let varlength: u64;
[INFO] [stdout]      |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_varlength`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]     --> src/lib.rs:1468:17
[INFO] [stdout]      |
[INFO] [stdout] 1468 |             Err(e) => {
[INFO] [stdout]      |                 ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `track`
[INFO] [stdout]     --> src/lib.rs:1524:36
[INFO] [stdout]      |
[INFO] [stdout] 1524 |     pub fn get_track_length(&self, track: usize) -> usize {
[INFO] [stdout]      |                                    ^^^^^ help: if this is intentional, prefix it with an underscore: `_track`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]     --> src/lib.rs:1672:24
[INFO] [stdout]      |
[INFO] [stdout] 1672 | fn build_key_signature(mut mi: u8, mut sf: u8) -> MIDIEvent {
[INFO] [stdout]      |                        ----^^
[INFO] [stdout]      |                        |
[INFO] [stdout]      |                        help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]     --> src/lib.rs:1672:36
[INFO] [stdout]      |
[INFO] [stdout] 1672 | fn build_key_signature(mut mi: u8, mut sf: u8) -> MIDIEvent {
[INFO] [stdout]      |                                    ----^^
[INFO] [stdout]      |                                    |
[INFO] [stdout]      |                                    help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]     --> src/lib.rs:1280:17
[INFO] [stdout]      |
[INFO] [stdout] 1280 |                 file.read(&mut buffer);
[INFO] [stdout]      |                 ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]      = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1280 |                 let _ = file.read(&mut buffer);
[INFO] [stdout]      |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]     --> src/lib.rs:1466:17
[INFO] [stdout]      |
[INFO] [stdout] 1466 |                 file.write_all(bytes.as_slice());
[INFO] [stdout]      |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]      |
[INFO] [stdout]      = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1466 |                 let _ = file.write_all(bytes.as_slice());
[INFO] [stdout]      |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 26 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.28s
[INFO] running `Command { std: "docker" "inspect" "24ca8d3baa0be194226e8c67bcd1c9631965b20e768ef4d4c1876bcc12026ade", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "24ca8d3baa0be194226e8c67bcd1c9631965b20e768ef4d4c1876bcc12026ade", kill_on_drop: false }`
[INFO] [stdout] 24ca8d3baa0be194226e8c67bcd1c9631965b20e768ef4d4c1876bcc12026ade
