[INFO] cloning repository https://github.com/Ermain-12/Introduction-to-Rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Ermain-12/Introduction-to-Rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FErmain-12%2FIntroduction-to-Rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FErmain-12%2FIntroduction-to-Rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 19db755187092c11f3f3ea13092682fc7bc92786
[INFO] checking Ermain-12/Introduction-to-Rust against try#8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8 for pr-82565
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FErmain-12%2FIntroduction-to-Rust" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Ermain-12/Introduction-to-Rust on toolchain 8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Ermain-12/Introduction-to-Rust
[INFO] finished tweaking git repo https://github.com/Ermain-12/Introduction-to-Rust
[INFO] tweaked toml for git repo https://github.com/Ermain-12/Introduction-to-Rust written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/Ermain-12/Introduction-to-Rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e83d4efd814a120c1a0dcbabd1b56cd6241d86171d29c3326bf987100583ecc3
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e83d4efd814a120c1a0dcbabd1b56cd6241d86171d29c3326bf987100583ecc3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e83d4efd814a120c1a0dcbabd1b56cd6241d86171d29c3326bf987100583ecc3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e83d4efd814a120c1a0dcbabd1b56cd6241d86171d29c3326bf987100583ecc3", kill_on_drop: false }`
[INFO] [stdout] e83d4efd814a120c1a0dcbabd1b56cd6241d86171d29c3326bf987100583ecc3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+8e3afc79c11f48cb3acd1be5b3b7de98fe3f93a8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a065a01425e72f1a472332bcb12df4090504c73e798add3d38731768eda3e2dc
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "a065a01425e72f1a472332bcb12df4090504c73e798add3d38731768eda3e2dc", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.40
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]    Compiling regex v1.0.0
[INFO] [stderr]     Checking utf8-ranges v1.0.0
[INFO] [stderr]     Checking regex-syntax v0.6.0
[INFO] [stderr]     Checking unreachable v1.0.0
[INFO] [stderr]     Checking thread_local v0.3.5
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking time v0.1.40
[INFO] [stderr]     Checking aho-corasick v0.6.4
[INFO] [stderr]     Checking hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |    let mut twenty_one = my_vec.pop();
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |    let mut twenty_one = my_vec.pop();
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.83s
[INFO] running `Command { std: "docker" "inspect" "a065a01425e72f1a472332bcb12df4090504c73e798add3d38731768eda3e2dc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a065a01425e72f1a472332bcb12df4090504c73e798add3d38731768eda3e2dc", kill_on_drop: false }`
[INFO] [stdout] a065a01425e72f1a472332bcb12df4090504c73e798add3d38731768eda3e2dc