[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] building Axect/Music_Tournament against master#ad211ced81509462cdfe4c29ed10f97279a0acae for pr-135216
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAxect%2FMusic_Tournament" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Axect/Music_Tournament on toolchain ad211ced81509462cdfe4c29ed10f97279a0acae
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 10 packages to latest compatible versions
[INFO] [stderr]       Adding rand v0.5.6 (available: v0.8.5)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0205dda85ff8e09ae529fc9ddb0543844efe53ce44bb5e021f4aa3f08b5ac1fe
[INFO] running `Command { std: "docker" "start" "-a" "0205dda85ff8e09ae529fc9ddb0543844efe53ce44bb5e021f4aa3f08b5ac1fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0205dda85ff8e09ae529fc9ddb0543844efe53ce44bb5e021f4aa3f08b5ac1fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0205dda85ff8e09ae529fc9ddb0543844efe53ce44bb5e021f4aa3f08b5ac1fe", kill_on_drop: false }`
[INFO] [stdout] 0205dda85ff8e09ae529fc9ddb0543844efe53ce44bb5e021f4aa3f08b5ac1fe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 50e670672cff6ab27f240bda1b11dc25f49e0867a9dc431526a3c883dfbf6c0f
[INFO] running `Command { std: "docker" "start" "-a" "50e670672cff6ab27f240bda1b11dc25f49e0867a9dc431526a3c883dfbf6c0f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.169
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand v0.5.6
[INFO] [stderr]    Compiling 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)]` 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)]` 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 3.56s
[INFO] running `Command { std: "docker" "inspect" "50e670672cff6ab27f240bda1b11dc25f49e0867a9dc431526a3c883dfbf6c0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "50e670672cff6ab27f240bda1b11dc25f49e0867a9dc431526a3c883dfbf6c0f", kill_on_drop: false }`
[INFO] [stdout] 50e670672cff6ab27f240bda1b11dc25f49e0867a9dc431526a3c883dfbf6c0f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 147a547958c86500eafdaddba3d876ed57a511bc4b956985ef8b28404608990f
[INFO] running `Command { std: "docker" "start" "-a" "147a547958c86500eafdaddba3d876ed57a511bc4b956985ef8b28404608990f", kill_on_drop: false }`
[INFO] [stderr]    Compiling 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)]` 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)]` 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 `test` profile [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "147a547958c86500eafdaddba3d876ed57a511bc4b956985ef8b28404608990f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "147a547958c86500eafdaddba3d876ed57a511bc4b956985ef8b28404608990f", kill_on_drop: false }`
[INFO] [stdout] 147a547958c86500eafdaddba3d876ed57a511bc4b956985ef8b28404608990f
