[INFO] cloning repository https://github.com/larkintuckerllc/r04_more_ownership
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/larkintuckerllc/r04_more_ownership" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flarkintuckerllc%2Fr04_more_ownership", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flarkintuckerllc%2Fr04_more_ownership'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] da40fb49bc6dccd7353e86918e6d22814b2bd9ae
[INFO] testing larkintuckerllc/r04_more_ownership against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flarkintuckerllc%2Fr04_more_ownership" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/larkintuckerllc/r04_more_ownership on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/larkintuckerllc/r04_more_ownership
[INFO] finished tweaking git repo https://github.com/larkintuckerllc/r04_more_ownership
[INFO] tweaked toml for git repo https://github.com/larkintuckerllc/r04_more_ownership written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/larkintuckerllc/r04_more_ownership already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9bbb1325b89a8f54c7b9a92a1fe0a4e8e684bb04eb63a01afdec12579398b381
[INFO] running `Command { std: "docker" "start" "-a" "9bbb1325b89a8f54c7b9a92a1fe0a4e8e684bb04eb63a01afdec12579398b381", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9bbb1325b89a8f54c7b9a92a1fe0a4e8e684bb04eb63a01afdec12579398b381", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9bbb1325b89a8f54c7b9a92a1fe0a4e8e684bb04eb63a01afdec12579398b381", kill_on_drop: false }`
[INFO] [stdout] 9bbb1325b89a8f54c7b9a92a1fe0a4e8e684bb04eb63a01afdec12579398b381
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9bff75a948ee55bdd405090966d0bae09ff3f48cc8d7884e7056403f7afb74b3
[INFO] running `Command { std: "docker" "start" "-a" "9bff75a948ee55bdd405090966d0bae09ff3f48cc8d7884e7056403f7afb74b3", kill_on_drop: false }`
[INFO] [stderr]    Compiling r04_more_ownership v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let mut s1 = String::from("hello");
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let mut phrase = String::from("hello world!");
[INFO] [stdout]    |         ----^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `Command { std: "docker" "inspect" "9bff75a948ee55bdd405090966d0bae09ff3f48cc8d7884e7056403f7afb74b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9bff75a948ee55bdd405090966d0bae09ff3f48cc8d7884e7056403f7afb74b3", kill_on_drop: false }`
[INFO] [stdout] 9bff75a948ee55bdd405090966d0bae09ff3f48cc8d7884e7056403f7afb74b3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7a30816a814ce93625177c22987a0cb28e1e3047723a15582e618c2720bf5210
[INFO] running `Command { std: "docker" "start" "-a" "7a30816a814ce93625177c22987a0cb28e1e3047723a15582e618c2720bf5210", kill_on_drop: false }`
[INFO] [stderr]    Compiling r04_more_ownership v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let mut s1 = String::from("hello");
[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: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let mut phrase = String::from("hello world!");
[INFO] [stdout]    |         ----^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.32s
[INFO] running `Command { std: "docker" "inspect" "7a30816a814ce93625177c22987a0cb28e1e3047723a15582e618c2720bf5210", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7a30816a814ce93625177c22987a0cb28e1e3047723a15582e618c2720bf5210", kill_on_drop: false }`
[INFO] [stdout] 7a30816a814ce93625177c22987a0cb28e1e3047723a15582e618c2720bf5210
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] fd4d0cb42e4ad195d8e29683dfcf226e2f4293f59d8fcf2ee91134f00ed0cc6b
[INFO] running `Command { std: "docker" "start" "-a" "fd4d0cb42e4ad195d8e29683dfcf226e2f4293f59d8fcf2ee91134f00ed0cc6b", kill_on_drop: false }`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:10:9
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let mut s1 = String::from("hello");
[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: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:21:9
[INFO] [stderr]    |
[INFO] [stderr] 21 |     let mut phrase = String::from("hello world!");
[INFO] [stderr]    |         ----^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: `r04_more_ownership` (bin "r04_more_ownership" test) generated 2 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.00s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/r04_more_ownership-8e6f306ab9a88751)
[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] running `Command { std: "docker" "inspect" "fd4d0cb42e4ad195d8e29683dfcf226e2f4293f59d8fcf2ee91134f00ed0cc6b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fd4d0cb42e4ad195d8e29683dfcf226e2f4293f59d8fcf2ee91134f00ed0cc6b", kill_on_drop: false }`
[INFO] [stdout] fd4d0cb42e4ad195d8e29683dfcf226e2f4293f59d8fcf2ee91134f00ed0cc6b