[INFO] cloning repository https://github.com/marcinwasowicz/Rust-Word-Count
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/marcinwasowicz/Rust-Word-Count" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarcinwasowicz%2FRust-Word-Count", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarcinwasowicz%2FRust-Word-Count'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 32d807d0d0d285e194059e76202048f536dff883
[INFO] checking marcinwasowicz/Rust-Word-Count against master#85c39893a761fe4c050523278da4e7e45ab42b6e for pr-134688-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmarcinwasowicz%2FRust-Word-Count" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/marcinwasowicz/Rust-Word-Count on toolchain 85c39893a761fe4c050523278da4e7e45ab42b6e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+85c39893a761fe4c050523278da4e7e45ab42b6e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/marcinwasowicz/Rust-Word-Count
[INFO] finished tweaking git repo https://github.com/marcinwasowicz/Rust-Word-Count
[INFO] tweaked toml for git repo https://github.com/marcinwasowicz/Rust-Word-Count written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/marcinwasowicz/Rust-Word-Count 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" "+85c39893a761fe4c050523278da4e7e45ab42b6e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+85c39893a761fe4c050523278da4e7e45ab42b6e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 39000030c2100e1ffb7e233a6de1c968c5303eb14f289301958f40ae68de703d
[INFO] running `Command { std: "docker" "start" "-a" "39000030c2100e1ffb7e233a6de1c968c5303eb14f289301958f40ae68de703d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "39000030c2100e1ffb7e233a6de1c968c5303eb14f289301958f40ae68de703d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "39000030c2100e1ffb7e233a6de1c968c5303eb14f289301958f40ae68de703d", kill_on_drop: false }`
[INFO] [stdout] 39000030c2100e1ffb7e233a6de1c968c5303eb14f289301958f40ae68de703d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+85c39893a761fe4c050523278da4e7e45ab42b6e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1fbf8eb58edac212ea3aeaeaeb68245ea54c610abf887c9989d2827e1ac66d1a
[INFO] running `Command { std: "docker" "start" "-a" "1fbf8eb58edac212ea3aeaeaeb68245ea54c610abf887c9989d2827e1ac66d1a", kill_on_drop: false }`
[INFO] [stderr]     Checking word_count v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/word_count_lib/file_ops.rs:23:17
[INFO] [stdout]    |
[INFO] [stdout] 23 |                 writeln!(file, "{}: {}", word, count);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/word_count_lib/file_ops.rs:23:17
[INFO] [stdout]    |
[INFO] [stdout] 23 |                 writeln!(file, "{}: {}", word, count);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.18s
[INFO] running `Command { std: "docker" "inspect" "1fbf8eb58edac212ea3aeaeaeb68245ea54c610abf887c9989d2827e1ac66d1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1fbf8eb58edac212ea3aeaeaeb68245ea54c610abf887c9989d2827e1ac66d1a", kill_on_drop: false }`
[INFO] [stdout] 1fbf8eb58edac212ea3aeaeaeb68245ea54c610abf887c9989d2827e1ac66d1a