[INFO] fetching crate mut 0.1.4...
[INFO] building mut-0.1.4 against try#d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6 for pr-146237-1
[INFO] extracting crate mut 0.1.4 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate mut 0.1.4
[INFO] finished tweaking crates.io crate mut 0.1.4
[INFO] tweaked toml for crates.io crate mut 0.1.4 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate mut 0.1.4 on toolchain d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate mut 0.1.4 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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 87a72badb4a548a0d61a750e86bc11150bb0c6d597cc0f2ed5f893edfbeb86c9
[INFO] running `Command { std: "docker" "start" "-a" "87a72badb4a548a0d61a750e86bc11150bb0c6d597cc0f2ed5f893edfbeb86c9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "87a72badb4a548a0d61a750e86bc11150bb0c6d597cc0f2ed5f893edfbeb86c9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "87a72badb4a548a0d61a750e86bc11150bb0c6d597cc0f2ed5f893edfbeb86c9", kill_on_drop: false }`
[INFO] [stdout] 87a72badb4a548a0d61a750e86bc11150bb0c6d597cc0f2ed5f893edfbeb86c9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e516b355b4adc39198fd761ea91b5b1012212841be2a10874db74c36b423c6ee
[INFO] running `Command { std: "docker" "start" "-a" "e516b355b4adc39198fd761ea91b5b1012212841be2a10874db74c36b423c6ee", kill_on_drop: false }`
[INFO] [stderr]    Compiling mut v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut args: Vec<String> = env::args().collect();
[INFO] [stdout]   |         ----^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `verify_length` is never used
[INFO] [stdout]    --> src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn verify_length(vector: &Vec<String>, length: usize) -> bool {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.52s
[INFO] running `Command { std: "docker" "inspect" "e516b355b4adc39198fd761ea91b5b1012212841be2a10874db74c36b423c6ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e516b355b4adc39198fd761ea91b5b1012212841be2a10874db74c36b423c6ee", kill_on_drop: false }`
[INFO] [stdout] e516b355b4adc39198fd761ea91b5b1012212841be2a10874db74c36b423c6ee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e5f48ab95433405f5793633e48df4cd104fba4aa3bf0b0f23df324627cfe2ba0
[INFO] running `Command { std: "docker" "start" "-a" "e5f48ab95433405f5793633e48df4cd104fba4aa3bf0b0f23df324627cfe2ba0", kill_on_drop: false }`
[INFO] [stderr]    Compiling mut v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let mut args: Vec<String> = env::args().collect();
[INFO] [stdout]   |         ----^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `verify_length` is never used
[INFO] [stdout]    --> src/main.rs:144:4
[INFO] [stdout]     |
[INFO] [stdout] 144 | fn verify_length(vector: &Vec<String>, length: usize) -> bool {
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.60s
[INFO] running `Command { std: "docker" "inspect" "e5f48ab95433405f5793633e48df4cd104fba4aa3bf0b0f23df324627cfe2ba0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5f48ab95433405f5793633e48df4cd104fba4aa3bf0b0f23df324627cfe2ba0", kill_on_drop: false }`
[INFO] [stdout] e5f48ab95433405f5793633e48df4cd104fba4aa3bf0b0f23df324627cfe2ba0
