[INFO] fetching crate mut 0.1.4...
[INFO] testing mut-0.1.4 against 1.90.0 for beta-1.91-3
[INFO] extracting crate mut 0.1.4 into /workspace/builds/worker-4-tc1/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-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate mut 0.1.4 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "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" "+1.90.0" "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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ddff76e86a020bc38e16732d337d1c74702520cb36c6ecfcb8c67a37fb29c321
[INFO] running `Command { std: "docker" "start" "-a" "ddff76e86a020bc38e16732d337d1c74702520cb36c6ecfcb8c67a37fb29c321", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ddff76e86a020bc38e16732d337d1c74702520cb36c6ecfcb8c67a37fb29c321", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ddff76e86a020bc38e16732d337d1c74702520cb36c6ecfcb8c67a37fb29c321", kill_on_drop: false }`
[INFO] [stdout] ddff76e86a020bc38e16732d337d1c74702520cb36c6ecfcb8c67a37fb29c321
[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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5396ed4d865d19486ee7dd90cf84a1da702a656ad261b44b190cd2c4f9596b81
[INFO] running `Command { std: "docker" "start" "-a" "5396ed4d865d19486ee7dd90cf84a1da702a656ad261b44b190cd2c4f9596b81", 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)]` 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)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.75s
[INFO] running `Command { std: "docker" "inspect" "5396ed4d865d19486ee7dd90cf84a1da702a656ad261b44b190cd2c4f9596b81", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5396ed4d865d19486ee7dd90cf84a1da702a656ad261b44b190cd2c4f9596b81", kill_on_drop: false }`
[INFO] [stdout] 5396ed4d865d19486ee7dd90cf84a1da702a656ad261b44b190cd2c4f9596b81
[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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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" "+1.90.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 83d91b65759a472ae6c117d81fbc619f74ead86b2b33b9c744dda422f03cb155
[INFO] running `Command { std: "docker" "start" "-a" "83d91b65759a472ae6c117d81fbc619f74ead86b2b33b9c744dda422f03cb155", 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)]` 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)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `Command { std: "docker" "inspect" "83d91b65759a472ae6c117d81fbc619f74ead86b2b33b9c744dda422f03cb155", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "83d91b65759a472ae6c117d81fbc619f74ead86b2b33b9c744dda422f03cb155", kill_on_drop: false }`
[INFO] [stdout] 83d91b65759a472ae6c117d81fbc619f74ead86b2b33b9c744dda422f03cb155
[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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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" "+1.90.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f14a87e9dd8e7570468da81ded65de6f47d6014516f9c3e15cdb47f3317ab00d
[INFO] running `Command { std: "docker" "start" "-a" "f14a87e9dd8e7570468da81ded65de6f47d6014516f9c3e15cdb47f3317ab00d", kill_on_drop: false }`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]  --> src/main.rs:9:9
[INFO] [stderr]   |
[INFO] [stderr] 9 |     let mut args: Vec<String> = env::args().collect();
[INFO] [stderr]   |         ----^^^^
[INFO] [stderr]   |         |
[INFO] [stderr]   |         help: remove this `mut`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function `verify_length` is never used
[INFO] [stderr]    --> src/main.rs:144:4
[INFO] [stderr]     |
[INFO] [stderr] 144 | fn verify_length(vector: &Vec<String>, length: usize) -> bool {
[INFO] [stderr]     |    ^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `mut` (bin "mut" test) generated 2 warnings (run `cargo fix --bin "mut" --tests` to apply 1 suggestion)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/mut-cba7fd79df9579c1)
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "f14a87e9dd8e7570468da81ded65de6f47d6014516f9c3e15cdb47f3317ab00d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f14a87e9dd8e7570468da81ded65de6f47d6014516f9c3e15cdb47f3317ab00d", kill_on_drop: false }`
[INFO] [stdout] f14a87e9dd8e7570468da81ded65de6f47d6014516f9c3e15cdb47f3317ab00d