[INFO] cloning repository https://github.com/abuit/rust-markov
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/abuit/rust-markov" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabuit%2Frust-markov", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabuit%2Frust-markov'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 95ec4e97ce1f93dc5a402b4659a30b83966e182f
[INFO] testing abuit/rust-markov against master#a77da2d454e6caa227a85b16410b95f93495e7e0 for pr-91031
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabuit%2Frust-markov" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/abuit/rust-markov on toolchain a77da2d454e6caa227a85b16410b95f93495e7e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/abuit/rust-markov
[INFO] finished tweaking git repo https://github.com/abuit/rust-markov
[INFO] tweaked toml for git repo https://github.com/abuit/rust-markov written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/abuit/rust-markov already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 35b70d4edc02dbfb4c06231c6873aeb01d1fa4fad65f4ccc715a30f283b0f813
[INFO] running `Command { std: "docker" "start" "-a" "35b70d4edc02dbfb4c06231c6873aeb01d1fa4fad65f4ccc715a30f283b0f813", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "35b70d4edc02dbfb4c06231c6873aeb01d1fa4fad65f4ccc715a30f283b0f813", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "35b70d4edc02dbfb4c06231c6873aeb01d1fa4fad65f4ccc715a30f283b0f813", kill_on_drop: false }`
[INFO] [stdout] 35b70d4edc02dbfb4c06231c6873aeb01d1fa4fad65f4ccc715a30f283b0f813
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 920477f2aca5274d1d5bb1bf556110705284fc9193ee011dfa33c1808ddba8af
[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" "920477f2aca5274d1d5bb1bf556110705284fc9193ee011dfa33c1808ddba8af", kill_on_drop: false }`
[INFO] [stderr]    Compiling rand_core v0.4.0
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling rust-markov v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:62:21
[INFO] [stdout]    |
[INFO] [stdout] 62 |                     &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 62 |                     let _ = &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.82s
[INFO] running `Command { std: "docker" "inspect" "920477f2aca5274d1d5bb1bf556110705284fc9193ee011dfa33c1808ddba8af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "920477f2aca5274d1d5bb1bf556110705284fc9193ee011dfa33c1808ddba8af", kill_on_drop: false }`
[INFO] [stdout] 920477f2aca5274d1d5bb1bf556110705284fc9193ee011dfa33c1808ddba8af
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9d8eb382a11b2ad7218ad08dde3060e5a49ed4de6ab70dc3cb614934a32cba81
[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" "9d8eb382a11b2ad7218ad08dde3060e5a49ed4de6ab70dc3cb614934a32cba81", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust-markov v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:62:21
[INFO] [stdout]    |
[INFO] [stdout] 62 |                     &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 62 |                     let _ = &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.04s
[INFO] running `Command { std: "docker" "inspect" "9d8eb382a11b2ad7218ad08dde3060e5a49ed4de6ab70dc3cb614934a32cba81", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9d8eb382a11b2ad7218ad08dde3060e5a49ed4de6ab70dc3cb614934a32cba81", kill_on_drop: false }`
[INFO] [stdout] 9d8eb382a11b2ad7218ad08dde3060e5a49ed4de6ab70dc3cb614934a32cba81
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 18efdffd98f76ed379c9dea85f735e0eb966dc6cec41cf4dce092ab74110ccce
[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" "18efdffd98f76ed379c9dea85f735e0eb966dc6cec41cf4dce092ab74110ccce", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unused borrow that must be used
[INFO] [stdout] running 0 tests
[INFO] [stderr]   --> src/main.rs:62:21
[INFO] [stdout] 
[INFO] [stderr]    |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr] 62 |                     &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stdout] 
[INFO] [stderr]    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 62 |                     let _ = &preceding_word_vec.1.push((&text[word_start..counter], 1));
[INFO] [stderr]    |                     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: `rust-markov` (bin "rust-markov" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/rust_markov-ed74b3a46166b762)
[INFO] running `Command { std: "docker" "inspect" "18efdffd98f76ed379c9dea85f735e0eb966dc6cec41cf4dce092ab74110ccce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "18efdffd98f76ed379c9dea85f735e0eb966dc6cec41cf4dce092ab74110ccce", kill_on_drop: false }`
[INFO] [stdout] 18efdffd98f76ed379c9dea85f735e0eb966dc6cec41cf4dce092ab74110ccce