[INFO] updating cached repository https://github.com/suelz/chapter_4
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5266a4ada4918881254cc79de937fbc229bb69a4
[INFO] testing suelz/chapter_4 against try#03a1ea71b075ab964b5278bc6e74cd6c52c36ee0 for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsuelz%2Fchapter_4" "/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/suelz/chapter_4 on toolchain 03a1ea71b075ab964b5278bc6e74cd6c52c36ee0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/suelz/chapter_4
[INFO] finished tweaking git repo https://github.com/suelz/chapter_4
[INFO] tweaked toml for git repo https://github.com/suelz/chapter_4 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/suelz/chapter_4 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] db1ec4a02e71bd112da9622a49e4a7fe8b63a9f2da6aa74e15304881fac31f38
[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" "db1ec4a02e71bd112da9622a49e4a7fe8b63a9f2da6aa74e15304881fac31f38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "db1ec4a02e71bd112da9622a49e4a7fe8b63a9f2da6aa74e15304881fac31f38", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db1ec4a02e71bd112da9622a49e4a7fe8b63a9f2da6aa74e15304881fac31f38", kill_on_drop: false }`
[INFO] [stdout] db1ec4a02e71bd112da9622a49e4a7fe8b63a9f2da6aa74e15304881fac31f38
[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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8f60cf62769786427c983d95f42f31d5ab529e05139de736e2509c53f6028341
[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" "8f60cf62769786427c983d95f42f31d5ab529e05139de736e2509c53f6028341", kill_on_drop: false }`
[INFO] [stderr]    Compiling ch4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let word = first_word(&x);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let mut x = String::from("Conor Kennedy");
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.88s
[INFO] running `Command { std: "docker" "inspect" "8f60cf62769786427c983d95f42f31d5ab529e05139de736e2509c53f6028341", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8f60cf62769786427c983d95f42f31d5ab529e05139de736e2509c53f6028341", kill_on_drop: false }`
[INFO] [stdout] 8f60cf62769786427c983d95f42f31d5ab529e05139de736e2509c53f6028341
[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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7c00c6299973df8ec7b25ec33cf8f6f3eed31a3c76d86db635615960b689b84d
[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" "7c00c6299973df8ec7b25ec33cf8f6f3eed31a3c76d86db635615960b689b84d", kill_on_drop: false }`
[INFO] [stderr]    Compiling ch4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `word`
[INFO] [stdout]   --> src/main.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let word = first_word(&x);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let mut x = String::from("Conor Kennedy");
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.61s
[INFO] running `Command { std: "docker" "inspect" "7c00c6299973df8ec7b25ec33cf8f6f3eed31a3c76d86db635615960b689b84d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7c00c6299973df8ec7b25ec33cf8f6f3eed31a3c76d86db635615960b689b84d", kill_on_drop: false }`
[INFO] [stdout] 7c00c6299973df8ec7b25ec33cf8f6f3eed31a3c76d86db635615960b689b84d
[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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+03a1ea71b075ab964b5278bc6e74cd6c52c36ee0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] fc8a5733cb091c47c2149191bf13fb229616cdfff03e6929d4fbdf58be669a12
[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" "fc8a5733cb091c47c2149191bf13fb229616cdfff03e6929d4fbdf58be669a12", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `word`
[INFO] [stderr]   --> src/main.rs:28:9
[INFO] [stderr]    |
[INFO] [stderr] 28 |     let word = first_word(&x);
[INFO] [stderr]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_word`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:26:9
[INFO] [stderr]    |
[INFO] [stderr] 26 |     let mut x = String::from("Conor Kennedy");
[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: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/ch4-9f52f9fc513fe4e4
[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
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "fc8a5733cb091c47c2149191bf13fb229616cdfff03e6929d4fbdf58be669a12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fc8a5733cb091c47c2149191bf13fb229616cdfff03e6929d4fbdf58be669a12", kill_on_drop: false }`
[INFO] [stdout] fc8a5733cb091c47c2149191bf13fb229616cdfff03e6929d4fbdf58be669a12