[INFO] cloning repository https://github.com/Etc3tera/RustFSExample
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Etc3tera/RustFSExample" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 819834b85797802f3788cd6a24028f7d8ca252a0
[INFO] checking Etc3tera/RustFSExample against master#5518eaa946291f00471af8b254b2a1715f234882 for pr-120393
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FEtc3tera%2FRustFSExample" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Etc3tera/RustFSExample on toolchain 5518eaa946291f00471af8b254b2a1715f234882
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+5518eaa946291f00471af8b254b2a1715f234882" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Etc3tera/RustFSExample
[INFO] finished tweaking git repo https://github.com/Etc3tera/RustFSExample
[INFO] tweaked toml for git repo https://github.com/Etc3tera/RustFSExample written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/Etc3tera/RustFSExample 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" "+5518eaa946291f00471af8b254b2a1715f234882" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bincode v1.1.4
[INFO] [stderr]   Downloaded serde_json v1.0.40
[INFO] [stderr]   Downloaded ryu v1.0.0
[INFO] [stderr]   Downloaded serde v1.0.100
[INFO] [stderr]   Downloaded proc-macro2 v1.0.3
[INFO] [stderr]   Downloaded serde_derive v1.0.100
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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" "+5518eaa946291f00471af8b254b2a1715f234882" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1b2cd68acef4aed88d061a34b6a2b707c4d7d6fe51bb7abeaca9ccb8c96ad16b
[INFO] running `Command { std: "docker" "start" "-a" "1b2cd68acef4aed88d061a34b6a2b707c4d7d6fe51bb7abeaca9ccb8c96ad16b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1b2cd68acef4aed88d061a34b6a2b707c4d7d6fe51bb7abeaca9ccb8c96ad16b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b2cd68acef4aed88d061a34b6a2b707c4d7d6fe51bb7abeaca9ccb8c96ad16b", kill_on_drop: false }`
[INFO] [stdout] 1b2cd68acef4aed88d061a34b6a2b707c4d7d6fe51bb7abeaca9ccb8c96ad16b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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" "+5518eaa946291f00471af8b254b2a1715f234882" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1cd3289b3eb95ef93ab4d99ae1f0c84db630982135726de265adc9a119c27bd8
[INFO] running `Command { std: "docker" "start" "-a" "1cd3289b3eb95ef93ab4d99ae1f0c84db630982135726de265adc9a119c27bd8", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.3
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling serde v1.0.100
[INFO] [stderr]    Compiling ryu v1.0.0
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]    Compiling autocfg v0.1.6
[INFO] [stderr]     Checking itoa v0.4.4
[INFO] [stderr]    Compiling bincode v1.1.4
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling serde_derive v1.0.100
[INFO] [stderr]     Checking serde_json v1.0.40
[INFO] [stderr]     Checking rust_fs_io v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::io::SeekFrom`
[INFO] [stdout]  --> src/serialize_binary.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::SeekFrom;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io::SeekFrom`
[INFO] [stdout]  --> src/serialize_binary.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::SeekFrom;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/serialize_text.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `serde_json::Result`
[INFO] [stdout]  --> src/serialize_text.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use serde_json::Result;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     stdin.lock().read_line(&mut line);
[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] 15 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fp.write_all(b"1");
[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] 16 |     let _ = fp.write_all(b"1");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     stdin.lock().read_line(&mut line);
[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] 17 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fp.write_all(b"2");
[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] 18 |     let _ = fp.write_all(b"2");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     stdin.lock().read_line(&mut line);
[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] 19 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fp.write_all(b"3");
[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] 20 |     let _ = fp.write_all(b"3");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     stdin.lock().read_line(&mut line);
[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] 21 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:22:5
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fp.seek(SeekFrom::Start(0));
[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] 22 |     let _ = fp.seek(SeekFrom::Start(0));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fp.write_all(b"4");
[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] 23 |     let _ = fp.write_all(b"4");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 24 |     stdin.lock().read_line(&mut line);
[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] 24 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 25 |     fp.write_all(b"5");
[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] 25 |     let _ = fp.write_all(b"5");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 26 |     stdin.lock().read_line(&mut line);
[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] 26 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 |     stdin.lock().read_line(&mut line);
[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] 15 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fp.write_all(b"1");
[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] 16 |     let _ = fp.write_all(b"1");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     stdin.lock().read_line(&mut line);
[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] 17 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     fp.write_all(b"2");
[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] 18 |     let _ = fp.write_all(b"2");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     stdin.lock().read_line(&mut line);
[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] 19 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fp.write_all(b"3");
[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] 20 |     let _ = fp.write_all(b"3");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     stdin.lock().read_line(&mut line);
[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] 21 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:22:5
[INFO] [stdout]    |
[INFO] [stdout] 22 |     fp.seek(SeekFrom::Start(0));
[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] 22 |     let _ = fp.seek(SeekFrom::Start(0));
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 |     fp.write_all(b"4");
[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] 23 |     let _ = fp.write_all(b"4");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 24 |     stdin.lock().read_line(&mut line);
[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] 24 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 25 |     fp.write_all(b"5");
[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] 25 |     let _ = fp.write_all(b"5");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/example.rs:26:5
[INFO] [stdout]    |
[INFO] [stdout] 26 |     stdin.lock().read_line(&mut line);
[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] 26 |     let _ = stdin.lock().read_line(&mut line);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_binary.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         fp.write_all(&bin);
[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] 47 |         let _ = fp.write_all(&bin);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_binary.rs:47:9
[INFO] [stdout]    |
[INFO] [stdout] 47 |         fp.write_all(&bin);
[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] 47 |         let _ = fp.write_all(&bin);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |         fp.write_all(json.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] 44 |         let _ = fp.write_all(json.as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fp.read_to_string(&mut buffer);
[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] 53 |     let _ = fp.read_to_string(&mut buffer);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:44:9
[INFO] [stdout]    |
[INFO] [stdout] 44 |         fp.write_all(json.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] 44 |         let _ = fp.write_all(json.as_bytes());
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/serialize_text.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     fp.read_to_string(&mut buffer);
[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] 53 |     let _ = fp.read_to_string(&mut buffer);
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.56s
[INFO] running `Command { std: "docker" "inspect" "1cd3289b3eb95ef93ab4d99ae1f0c84db630982135726de265adc9a119c27bd8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1cd3289b3eb95ef93ab4d99ae1f0c84db630982135726de265adc9a119c27bd8", kill_on_drop: false }`
[INFO] [stdout] 1cd3289b3eb95ef93ab4d99ae1f0c84db630982135726de265adc9a119c27bd8
