[INFO] cloning repository https://github.com/fredrb/chip-8
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/fredrb/chip-8" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffredrb%2Fchip-8", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffredrb%2Fchip-8'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5c088c6209279aee50ea36770219ad6e382f5b57
[INFO] checking fredrb/chip-8 against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffredrb%2Fchip-8" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/fredrb/chip-8 on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/fredrb/chip-8
[INFO] finished tweaking git repo https://github.com/fredrb/chip-8
[INFO] tweaked toml for git repo https://github.com/fredrb/chip-8 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/fredrb/chip-8 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded c_vec v1.3.3
[INFO] [stderr]   Downloaded sdl2 v0.34.3
[INFO] [stderr]   Downloaded sdl2-sys v0.34.3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 24b8c9af5524dc539da69a3f7b288377b07db21c1f052b7c9e25749b22aeb3fa
[INFO] running `Command { std: "docker" "start" "-a" "24b8c9af5524dc539da69a3f7b288377b07db21c1f052b7c9e25749b22aeb3fa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "24b8c9af5524dc539da69a3f7b288377b07db21c1f052b7c9e25749b22aeb3fa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "24b8c9af5524dc539da69a3f7b288377b07db21c1f052b7c9e25749b22aeb3fa", kill_on_drop: false }`
[INFO] [stdout] 24b8c9af5524dc539da69a3f7b288377b07db21c1f052b7c9e25749b22aeb3fa
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 573dbd08ffea48d8cde5760da03f352299fceb55a1b9731f07faa96b5b653751
[INFO] running `Command { std: "docker" "start" "-a" "573dbd08ffea48d8cde5760da03f352299fceb55a1b9731f07faa96b5b653751", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.79
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling getrandom v0.1.15
[INFO] [stderr]    Compiling version-compare v0.0.10
[INFO] [stderr]     Checking ppv-lite86 v0.2.9
[INFO] [stderr]    Compiling sdl2 v0.34.3
[INFO] [stderr]     Checking c_vec v1.3.3
[INFO] [stderr]    Compiling sdl2-sys v0.34.3
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking sdl-chip-8 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `thread`, `time`
[INFO] [stdout]  --> src/cpu.rs:3:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::{thread, time};
[INFO] [stdout]   |           ^^^^^^  ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/graphics.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/input.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `thread`, `time`
[INFO] [stdout]  --> src/cpu.rs:3:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::{thread, time};
[INFO] [stdout]   |           ^^^^^^  ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/graphics.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/input.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `cls`, `key_pressed`, `key`, `waiting_key`, `buf_key_received`, and `key_lock` are never read
[INFO] [stdout]   --> src/cpu.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 39 | pub struct Machine {
[INFO] [stdout]    |            ------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 49 |     pub cls: bool,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 52 |     pub key_pressed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 53 |     pub key: u8,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 56 |     pub waiting_key: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 57 |     buf_key_received: i8,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 58 |     key_lock: u8,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |         self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[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] 27 |         let _ = self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |         self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[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] 28 |         let _ = self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[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] 29 |         let _ = self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[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] 30 |         let _ = self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |         self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[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] 31 |         let _ = self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         self.f.write_all(String::from("\nStack:").as_bytes());
[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] 33 |         let _ = self.f.write_all(String::from("\nStack:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             self.f.write(format!("{} | ", i).as_bytes());
[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] 35 |             let _ = self.f.write(format!("{} | ", i).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         self.f.write_all(String::from("\nRegisters:").as_bytes());
[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] 38 |         let _ = self.f.write_all(String::from("\nRegisters:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |             self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[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] 40 |             let _ = self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `cls`, `key_pressed`, `key`, `waiting_key`, `buf_key_received`, and `key_lock` are never read
[INFO] [stdout]   --> src/cpu.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 39 | pub struct Machine {
[INFO] [stdout]    |            ------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 49 |     pub cls: bool,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 52 |     pub key_pressed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 53 |     pub key: u8,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 56 |     pub waiting_key: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 57 |     buf_key_received: i8,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 58 |     key_lock: u8,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |         self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[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] 27 |         let _ = self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |         self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[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] 28 |         let _ = self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[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] 29 |         let _ = self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[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] 30 |         let _ = self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |         self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[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] 31 |         let _ = self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         self.f.write_all(String::from("\nStack:").as_bytes());
[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] 33 |         let _ = self.f.write_all(String::from("\nStack:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             self.f.write(format!("{} | ", i).as_bytes());
[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] 35 |             let _ = self.f.write(format!("{} | ", i).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         self.f.write_all(String::from("\nRegisters:").as_bytes());
[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] 38 |         let _ = self.f.write_all(String::from("\nRegisters:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |             self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[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] 40 |             let _ = self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.05s
[INFO] running `Command { std: "docker" "inspect" "573dbd08ffea48d8cde5760da03f352299fceb55a1b9731f07faa96b5b653751", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "573dbd08ffea48d8cde5760da03f352299fceb55a1b9731f07faa96b5b653751", kill_on_drop: false }`
[INFO] [stdout] 573dbd08ffea48d8cde5760da03f352299fceb55a1b9731f07faa96b5b653751
[INFO] checking fredrb/chip-8 against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffredrb%2Fchip-8" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/fredrb/chip-8 on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/fredrb/chip-8
[INFO] finished tweaking git repo https://github.com/fredrb/chip-8
[INFO] tweaked toml for git repo https://github.com/fredrb/chip-8 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/fredrb/chip-8 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b1dee8dc084591719052ca6e16e92ce60f9382d84b0c55ee2f65831700bfced6
[INFO] running `Command { std: "docker" "start" "-a" "b1dee8dc084591719052ca6e16e92ce60f9382d84b0c55ee2f65831700bfced6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b1dee8dc084591719052ca6e16e92ce60f9382d84b0c55ee2f65831700bfced6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b1dee8dc084591719052ca6e16e92ce60f9382d84b0c55ee2f65831700bfced6", kill_on_drop: false }`
[INFO] [stdout] b1dee8dc084591719052ca6e16e92ce60f9382d84b0c55ee2f65831700bfced6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4b00e8db078a09748efbfd61cf179c592d1a1d3aaf95318c9b24d19ce186e6c9
[INFO] running `Command { std: "docker" "start" "-a" "4b00e8db078a09748efbfd61cf179c592d1a1d3aaf95318c9b24d19ce186e6c9", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.79
[INFO] [stderr]    Compiling version-compare v0.0.10
[INFO] [stderr]    Compiling getrandom v0.1.15
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling sdl2 v0.34.3
[INFO] [stderr]     Checking ppv-lite86 v0.2.9
[INFO] [stderr]     Checking c_vec v1.3.3
[INFO] [stderr]    Compiling sdl2-sys v0.34.3
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking sdl-chip-8 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `thread`, `time`
[INFO] [stdout]  --> src/cpu.rs:3:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::{thread, time};
[INFO] [stdout]   |           ^^^^^^  ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/graphics.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/input.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `thread`, `time`
[INFO] [stdout]  --> src/cpu.rs:3:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::{thread, time};
[INFO] [stdout]   |           ^^^^^^  ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/graphics.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `sdl2` is imported redundantly
[INFO] [stdout]  --> src/external/input.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use sdl2;
[INFO] [stdout]   |     ^^^^ the item `sdl2` is already defined by prelude
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `cls`, `key_pressed`, `key`, `waiting_key`, `buf_key_received`, and `key_lock` are never read
[INFO] [stdout]   --> src/cpu.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 39 | pub struct Machine {
[INFO] [stdout]    |            ------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 49 |     pub cls: bool,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 52 |     pub key_pressed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 53 |     pub key: u8,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 56 |     pub waiting_key: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 57 |     buf_key_received: i8,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 58 |     key_lock: u8,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |         self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[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] 27 |         let _ = self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |         self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[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] 28 |         let _ = self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[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] 29 |         let _ = self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[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] 30 |         let _ = self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |         self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[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] 31 |         let _ = self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         self.f.write_all(String::from("\nStack:").as_bytes());
[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] 33 |         let _ = self.f.write_all(String::from("\nStack:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             self.f.write(format!("{} | ", i).as_bytes());
[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] 35 |             let _ = self.f.write(format!("{} | ", i).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         self.f.write_all(String::from("\nRegisters:").as_bytes());
[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] 38 |         let _ = self.f.write_all(String::from("\nRegisters:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |             self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[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] 40 |             let _ = self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `cls`, `key_pressed`, `key`, `waiting_key`, `buf_key_received`, and `key_lock` are never read
[INFO] [stdout]   --> src/cpu.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 39 | pub struct Machine {
[INFO] [stdout]    |            ------- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 49 |     pub cls: bool,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 52 |     pub key_pressed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 53 |     pub key: u8,
[INFO] [stdout]    |         ^^^
[INFO] [stdout] ...
[INFO] [stdout] 56 |     pub waiting_key: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 57 |     buf_key_received: i8,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 58 |     key_lock: u8,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:27:9
[INFO] [stdout]    |
[INFO] [stdout] 27 |         self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[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] 27 |         let _ = self.f.write(format!("\nINSTRUCTION: {:#x}", last_instruction).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |         self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[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] 28 |         let _ = self.f.write_all(format!("\nI: {} |", m.i).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |         self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[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] 29 |         let _ = self.f.write_all(format!("Timer: {} |", m.delay_timer).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[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] 30 |         let _ = self.f.write_all(format!("pc: {} | ", m.pc).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |         self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[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] 31 |         let _ = self.f.write_all(format!("sp: {} | ", m.sp).as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:33:9
[INFO] [stdout]    |
[INFO] [stdout] 33 |         self.f.write_all(String::from("\nStack:").as_bytes());
[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] 33 |         let _ = self.f.write_all(String::from("\nStack:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             self.f.write(format!("{} | ", i).as_bytes());
[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] 35 |             let _ = self.f.write(format!("{} | ", i).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |         self.f.write_all(String::from("\nRegisters:").as_bytes());
[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] 38 |         let _ = self.f.write_all(String::from("\nRegisters:").as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:40:13
[INFO] [stdout]    |
[INFO] [stdout] 40 |             self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[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] 40 |             let _ = self.f.write(format!("{:#x}: {} | ", i, m.registers[i]).as_bytes());
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.09s
[INFO] running `Command { std: "docker" "inspect" "4b00e8db078a09748efbfd61cf179c592d1a1d3aaf95318c9b24d19ce186e6c9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b00e8db078a09748efbfd61cf179c592d1a1d3aaf95318c9b24d19ce186e6c9", kill_on_drop: false }`
[INFO] [stdout] 4b00e8db078a09748efbfd61cf179c592d1a1d3aaf95318c9b24d19ce186e6c9