[INFO] fetching crate mut 0.1.4...
[INFO] testing mut-0.1.4 against try#dec9417b8611e34e787a3e4c37686b5131f9e5c5 for pr-154210-2
[INFO] extracting crate mut 0.1.4 into /workspace/builds/worker-1-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-1-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate mut 0.1.4 on toolchain dec9417b8611e34e787a3e4c37686b5131f9e5c5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "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" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 32111a6111391cccac44ae6f54797b47132b9bdc10a0f1e205d369a682042f1c
[INFO] running `Command { std: "docker" "start" "-a" "32111a6111391cccac44ae6f54797b47132b9bdc10a0f1e205d369a682042f1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "32111a6111391cccac44ae6f54797b47132b9bdc10a0f1e205d369a682042f1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32111a6111391cccac44ae6f54797b47132b9bdc10a0f1e205d369a682042f1c", kill_on_drop: false }`
[INFO] [stdout] 32111a6111391cccac44ae6f54797b47132b9bdc10a0f1e205d369a682042f1c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 247617e51dde89eddb1b4d5621cba2207c5bbd6d98fd12915294216729cc4b0c
[INFO] running `Command { std: "docker" "start" "-a" "247617e51dde89eddb1b4d5621cba2207c5bbd6d98fd12915294216729cc4b0c", 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 0.48s
[INFO] running `Command { std: "docker" "inspect" "247617e51dde89eddb1b4d5621cba2207c5bbd6d98fd12915294216729cc4b0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "247617e51dde89eddb1b4d5621cba2207c5bbd6d98fd12915294216729cc4b0c", kill_on_drop: false }`
[INFO] [stdout] 247617e51dde89eddb1b4d5621cba2207c5bbd6d98fd12915294216729cc4b0c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 52bb67dff00b560475935d8f8abadf16992dd96c935206ff50489fee19a87b42
[INFO] running `Command { std: "docker" "start" "-a" "52bb67dff00b560475935d8f8abadf16992dd96c935206ff50489fee19a87b42", 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 0.39s
[INFO] running `Command { std: "docker" "inspect" "52bb67dff00b560475935d8f8abadf16992dd96c935206ff50489fee19a87b42", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52bb67dff00b560475935d8f8abadf16992dd96c935206ff50489fee19a87b42", kill_on_drop: false }`
[INFO] [stdout] 52bb67dff00b560475935d8f8abadf16992dd96c935206ff50489fee19a87b42
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f5e40fd4c0bfca8eaa7c0dbe71b97736ba990051f9c5f5d3a381355d4df0b4e1
[INFO] running `Command { std: "docker" "start" "-a" "f5e40fd4c0bfca8eaa7c0dbe71b97736ba990051f9c5f5d3a381355d4df0b4e1", 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)]` (part of `#[warn(unused)]`) 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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `mut` (bin "mut" test) generated 2 warnings (run `cargo fix --bin "mut" -p mut --tests` to apply 1 suggestion)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stdout] 
[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] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/mut-8ef19af15f67b78d)
[INFO] running `Command { std: "docker" "inspect" "f5e40fd4c0bfca8eaa7c0dbe71b97736ba990051f9c5f5d3a381355d4df0b4e1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5e40fd4c0bfca8eaa7c0dbe71b97736ba990051f9c5f5d3a381355d4df0b4e1", kill_on_drop: false }`
[INFO] [stdout] f5e40fd4c0bfca8eaa7c0dbe71b97736ba990051f9c5f5d3a381355d4df0b4e1