[INFO] cloning repository https://github.com/Axect/Music_Tournament
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Axect/Music_Tournament" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAxect%2FMusic_Tournament", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAxect%2FMusic_Tournament'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f7bfc81f341e02c6237479346d10d94d6a6dfccc
[INFO] checking Axect/Music_Tournament against master#485ec3fbcc12fa14ef6596dabb125ad710499c9e for pr-157710
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAxect%2FMusic_Tournament" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/Axect/Music_Tournament
[INFO] finished tweaking git repo https://github.com/Axect/Music_Tournament
[INFO] tweaked toml for git repo https://github.com/Axect/Music_Tournament written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/Axect/Music_Tournament on toolchain 485ec3fbcc12fa14ef6596dabb125ad710499c9e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+485ec3fbcc12fa14ef6596dabb125ad710499c9e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+485ec3fbcc12fa14ef6596dabb125ad710499c9e" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 10 packages to latest compatible versions
[INFO] [stderr]       Adding rand v0.5.6 (available: v0.10.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+485ec3fbcc12fa14ef6596dabb125ad710499c9e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:3a6becf2bc8dde7f3fa57ede90e4f284e72d296796fc446bbb1e2c7cc0530151" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d
[INFO] running `Command { std: "docker" "start" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d" "/opt/rustwide/cargo-home/bin/cargo" "+485ec3fbcc12fa14ef6596dabb125ad710499c9e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d" "/opt/rustwide/cargo-home/bin/cargo" "+485ec3fbcc12fa14ef6596dabb125ad710499c9e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.186
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stderr]     Checking Music_Tournament v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `DirEntry`
[INFO] [stdout]  --> src/main.rs:7:21
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::fs::{self, DirEntry, File};
[INFO] [stdout]   |                     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `DirEntry`
[INFO] [stdout]  --> src/main.rs:7:21
[INFO] [stdout]   |
[INFO] [stdout] 7 | use std::fs::{self, DirEntry, File};
[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 |         write_mp3_list("save_0.txt", &result);
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 33 |         let _ = write_mp3_list("save_0.txt", &result);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:99:13
[INFO] [stdout]    |
[INFO] [stdout] 99 |             write_mp3_list("temp_1.txt", &result2);
[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] 99 |             let _ = write_mp3_list("temp_1.txt", &result2);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:101:13
[INFO] [stdout]     |
[INFO] [stdout] 101 |             write_mp3_list("log.txt", &vec![temp_write]);
[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] 101 |             let _ = write_mp3_list("log.txt", &vec![temp_write]);
[INFO] [stdout]     |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:110:5
[INFO] [stdout]     |
[INFO] [stdout] 110 |     write_mp3_list("save_1.txt", &result2);
[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] 110 |     let _ = write_mp3_list("save_1.txt", &result2);
[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 |         write_mp3_list("save_0.txt", &result);
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 33 |         let _ = write_mp3_list("save_0.txt", &result);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:99:13
[INFO] [stdout]    |
[INFO] [stdout] 99 |             write_mp3_list("temp_1.txt", &result2);
[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] 99 |             let _ = write_mp3_list("temp_1.txt", &result2);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:101:13
[INFO] [stdout]     |
[INFO] [stdout] 101 |             write_mp3_list("log.txt", &vec![temp_write]);
[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] 101 |             let _ = write_mp3_list("log.txt", &vec![temp_write]);
[INFO] [stdout]     |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:110:5
[INFO] [stdout]     |
[INFO] [stdout] 110 |     write_mp3_list("save_1.txt", &result2);
[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] 110 |     let _ = write_mp3_list("save_1.txt", &result2);
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.02s
[INFO] running `Command { std: "docker" "inspect" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d", kill_on_drop: false }`
[INFO] [stdout] bb40f4b52048794545e013c4aeb0e4efd6d9c30e4091a2810417ce1c12ee921d
