[INFO] cloning repository https://github.com/brunodea/gebemula
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/brunodea/gebemula" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrunodea%2Fgebemula", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrunodea%2Fgebemula'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 19ef00deb2d78ee88dd9a357db48568c7a0329a6
[INFO] checking brunodea/gebemula against master#33fdb797f59421c7bbecaa4588ed5d7a31a9494a for pr-87190-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrunodea%2Fgebemula" "/workspace/builds/worker-64/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-64/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/brunodea/gebemula on toolchain 33fdb797f59421c7bbecaa4588ed5d7a31a9494a
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/brunodea/gebemula
[INFO] finished tweaking git repo https://github.com/brunodea/gebemula
[INFO] tweaked toml for git repo https://github.com/brunodea/gebemula written to /workspace/builds/worker-64/source/Cargo.toml
[INFO] crate git repo https://github.com/brunodea/gebemula already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-64/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-64/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8ac9efe575d787bf31908e0fbbf14cfb18d578dd23e2843337b2e889a5a26d35
[INFO] running `Command { std: "docker" "start" "-a" "8ac9efe575d787bf31908e0fbbf14cfb18d578dd23e2843337b2e889a5a26d35", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8ac9efe575d787bf31908e0fbbf14cfb18d578dd23e2843337b2e889a5a26d35", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8ac9efe575d787bf31908e0fbbf14cfb18d578dd23e2843337b2e889a5a26d35", kill_on_drop: false }`
[INFO] [stdout] 8ac9efe575d787bf31908e0fbbf14cfb18d578dd23e2843337b2e889a5a26d35
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-64/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-64/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c2b020a953d9a1f1a63c0352ae4d16bd9a76fc448a62528d61999d31971304fa
[INFO] running `Command { std: "docker" "start" "-a" "c2b020a953d9a1f1a63c0352ae4d16bd9a76fc448a62528d61999d31971304fa", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling num-traits v0.2.4
[INFO] [stderr]    Compiling num-integer v0.1.38
[INFO] [stderr]    Compiling num-iter v0.1.37
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking unicode-width v0.1.4
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking strsim v0.7.0
[INFO] [stderr]     Checking bitflags v0.7.0
[INFO] [stderr]     Checking arrayref v0.3.4
[INFO] [stderr]     Checking rand v0.4.2
[INFO] [stderr]     Checking atty v0.2.10
[INFO] [stderr]    Compiling sdl2-sys v0.31.0
[INFO] [stderr]    Compiling blip_buf-sys v0.1.3
[INFO] [stderr]     Checking textwrap v0.9.0
[INFO] [stderr]     Checking clap v2.31.2
[INFO] [stderr]     Checking blip_buf v0.1.4
[INFO] [stderr]     Checking rand v0.3.22
[INFO] [stderr]     Checking num v0.1.42
[INFO] [stderr]     Checking sdl2 v0.31.0
[INFO] [stderr]     Checking gebemula v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]     --> src/cpu/mod.rs:1093:13
[INFO] [stdout]      |
[INFO] [stdout] 1093 |             _ => unreachable!(),
[INFO] [stdout]      |             ^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/debugger.rs:579:13
[INFO] [stdout]     |
[INFO] [stdout] 579 |             _ => unreachable!(),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/mem/mod.rs:142:13
[INFO] [stdout]     |
[INFO] [stdout] 142 |             _ => panic!("Out of bound! Tried to write to {:#x}.", address),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/mem/mod.rs:210:13
[INFO] [stdout]     |
[INFO] [stdout] 210 |             _ => panic!("Out of bound! Tried to read from {:#x}.", address),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]     --> src/cpu/mod.rs:1093:13
[INFO] [stdout]      |
[INFO] [stdout] 1093 |             _ => unreachable!(),
[INFO] [stdout]      |             ^
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/debugger.rs:579:13
[INFO] [stdout]     |
[INFO] [stdout] 579 |             _ => unreachable!(),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/mem/mod.rs:142:13
[INFO] [stdout]     |
[INFO] [stdout] 142 |             _ => panic!("Out of bound! Tried to write to {:#x}.", address),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/mem/mod.rs:210:13
[INFO] [stdout]     |
[INFO] [stdout] 210 |             _ => panic!("Out of bound! Tried to read from {:#x}.", address),
[INFO] [stdout]     |             ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `IO_END`
[INFO] [stdout]  --> src/peripherals/sound.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | const IO_END: u16 = 0xFF3F;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR41_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:31:1
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub const NR41_REGISTER_ADDR: u16 = 0xFF20;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR42_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:32:1
[INFO] [stdout]    |
[INFO] [stdout] 32 | pub const NR42_REGISTER_ADDR: u16 = 0xFF21;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR43_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:33:1
[INFO] [stdout]    |
[INFO] [stdout] 33 | pub const NR43_REGISTER_ADDR: u16 = 0xFF22;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR44_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:34:1
[INFO] [stdout]    |
[INFO] [stdout] 34 | pub const NR44_REGISTER_ADDR: u16 = 0xFF23;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `OUTPUT_FREQUENCY`
[INFO] [stdout]   --> src/peripherals/sound.rs:45:1
[INFO] [stdout]    |
[INFO] [stdout] 45 | pub const OUTPUT_FREQUENCY: u32 = CPU_FREQUENCY_HZ;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `OUTPUT_CHANNELS`
[INFO] [stdout]   --> src/peripherals/sound.rs:46:1
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub const OUTPUT_CHANNELS: usize = 2;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `output_on`
[INFO] [stdout]    --> src/peripherals/sound.rs:136:8
[INFO] [stdout]     |
[INFO] [stdout] 136 |     fn output_on(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `frequency`
[INFO] [stdout]    --> src/peripherals/sound.rs:163:8
[INFO] [stdout]     |
[INFO] [stdout] 163 |     fn frequency(&self) -> u16 {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `channel_num`
[INFO] [stdout]    --> src/peripherals/sound.rs:197:5
[INFO] [stdout]     |
[INFO] [stdout] 197 |     channel_num: u8,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `ch4`
[INFO] [stdout]    --> src/peripherals/sound.rs:453:5
[INFO] [stdout]     |
[INFO] [stdout] 453 |     ch4: NoiseVoice,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `nr4x`
[INFO] [stdout]    --> src/peripherals/sound.rs:678:8
[INFO] [stdout]     |
[INFO] [stdout] 678 |     fn nr4x(&self) -> &[u8; 5] {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `nr5x`
[INFO] [stdout]    --> src/peripherals/sound.rs:682:8
[INFO] [stdout]     |
[INFO] [stdout] 682 |     fn nr5x(&self) -> &[u8; 3] {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `wave_table`
[INFO] [stdout]    --> src/peripherals/sound.rs:686:8
[INFO] [stdout]     |
[INFO] [stdout] 686 |     fn wave_table(&self) -> &[u8] {
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/mem/cartridge.rs:185:5
[INFO] [stdout]     |
[INFO] [stdout] 185 |     &rom_data[..copy_len].copy_from_slice(&rom[..copy_len]);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 185 |     let _ = &rom_data[..copy_len].copy_from_slice(&rom[..copy_len]);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/mem/cartridge.rs:199:5
[INFO] [stdout]     |
[INFO] [stdout] 199 |     &ram_data[..copy_len].copy_from_slice(&battery[..copy_len]);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 199 |     let _ = &ram_data[..copy_len].copy_from_slice(&battery[..copy_len]);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 20 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `IO_END`
[INFO] [stdout]  --> src/peripherals/sound.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | const IO_END: u16 = 0xFF3F;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR41_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:31:1
[INFO] [stdout]    |
[INFO] [stdout] 31 | pub const NR41_REGISTER_ADDR: u16 = 0xFF20;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR42_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:32:1
[INFO] [stdout]    |
[INFO] [stdout] 32 | pub const NR42_REGISTER_ADDR: u16 = 0xFF21;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR43_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:33:1
[INFO] [stdout]    |
[INFO] [stdout] 33 | pub const NR43_REGISTER_ADDR: u16 = 0xFF22;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `NR44_REGISTER_ADDR`
[INFO] [stdout]   --> src/peripherals/sound.rs:34:1
[INFO] [stdout]    |
[INFO] [stdout] 34 | pub const NR44_REGISTER_ADDR: u16 = 0xFF23;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `OUTPUT_FREQUENCY`
[INFO] [stdout]   --> src/peripherals/sound.rs:45:1
[INFO] [stdout]    |
[INFO] [stdout] 45 | pub const OUTPUT_FREQUENCY: u32 = CPU_FREQUENCY_HZ;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `OUTPUT_CHANNELS`
[INFO] [stdout]   --> src/peripherals/sound.rs:46:1
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub const OUTPUT_CHANNELS: usize = 2;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `output_on`
[INFO] [stdout]    --> src/peripherals/sound.rs:136:8
[INFO] [stdout]     |
[INFO] [stdout] 136 |     fn output_on(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `frequency`
[INFO] [stdout]    --> src/peripherals/sound.rs:163:8
[INFO] [stdout]     |
[INFO] [stdout] 163 |     fn frequency(&self) -> u16 {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `channel_num`
[INFO] [stdout]    --> src/peripherals/sound.rs:197:5
[INFO] [stdout]     |
[INFO] [stdout] 197 |     channel_num: u8,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `ch4`
[INFO] [stdout]    --> src/peripherals/sound.rs:453:5
[INFO] [stdout]     |
[INFO] [stdout] 453 |     ch4: NoiseVoice,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `nr4x`
[INFO] [stdout]    --> src/peripherals/sound.rs:678:8
[INFO] [stdout]     |
[INFO] [stdout] 678 |     fn nr4x(&self) -> &[u8; 5] {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `nr5x`
[INFO] [stdout]    --> src/peripherals/sound.rs:682:8
[INFO] [stdout]     |
[INFO] [stdout] 682 |     fn nr5x(&self) -> &[u8; 3] {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `wave_table`
[INFO] [stdout]    --> src/peripherals/sound.rs:686:8
[INFO] [stdout]     |
[INFO] [stdout] 686 |     fn wave_table(&self) -> &[u8] {
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/mem/cartridge.rs:185:5
[INFO] [stdout]     |
[INFO] [stdout] 185 |     &rom_data[..copy_len].copy_from_slice(&rom[..copy_len]);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 185 |     let _ = &rom_data[..copy_len].copy_from_slice(&rom[..copy_len]);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/mem/cartridge.rs:199:5
[INFO] [stdout]     |
[INFO] [stdout] 199 |     &ram_data[..copy_len].copy_from_slice(&battery[..copy_len]);
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 199 |     let _ = &ram_data[..copy_len].copy_from_slice(&battery[..copy_len]);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 20 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.40s
[INFO] running `Command { std: "docker" "inspect" "c2b020a953d9a1f1a63c0352ae4d16bd9a76fc448a62528d61999d31971304fa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c2b020a953d9a1f1a63c0352ae4d16bd9a76fc448a62528d61999d31971304fa", kill_on_drop: false }`
[INFO] [stdout] c2b020a953d9a1f1a63c0352ae4d16bd9a76fc448a62528d61999d31971304fa