[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 try#a0cd57eba5d417638d3351ba13fc414ad1a24bec 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-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/marcinwasowicz/Rust-Word-Count on toolchain a0cd57eba5d417638d3351ba13fc414ad1a24bec [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+a0cd57eba5d417638d3351ba13fc414ad1a24bec" "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-tc2/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" "+a0cd57eba5d417638d3351ba13fc414ad1a24bec" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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" "+a0cd57eba5d417638d3351ba13fc414ad1a24bec" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] 6f2372ce6b9a7a83dc38fc6d9304a88bb423ecdb463bdc85033b36cf3bf5a369 [INFO] running `Command { std: "docker" "start" "-a" "6f2372ce6b9a7a83dc38fc6d9304a88bb423ecdb463bdc85033b36cf3bf5a369", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "6f2372ce6b9a7a83dc38fc6d9304a88bb423ecdb463bdc85033b36cf3bf5a369", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "6f2372ce6b9a7a83dc38fc6d9304a88bb423ecdb463bdc85033b36cf3bf5a369", kill_on_drop: false }` [INFO] [stdout] 6f2372ce6b9a7a83dc38fc6d9304a88bb423ecdb463bdc85033b36cf3bf5a369 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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" "+a0cd57eba5d417638d3351ba13fc414ad1a24bec" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] 3df14d8a6abe37ce69b4cf7ea62304206fece32ce9ede42a47f1b2a7e6ad0fd7 [INFO] running `Command { std: "docker" "start" "-a" "3df14d8a6abe37ce69b4cf7ea62304206fece32ce9ede42a47f1b2a7e6ad0fd7", 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 0.19s [INFO] running `Command { std: "docker" "inspect" "3df14d8a6abe37ce69b4cf7ea62304206fece32ce9ede42a47f1b2a7e6ad0fd7", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "3df14d8a6abe37ce69b4cf7ea62304206fece32ce9ede42a47f1b2a7e6ad0fd7", kill_on_drop: false }` [INFO] [stdout] 3df14d8a6abe37ce69b4cf7ea62304206fece32ce9ede42a47f1b2a7e6ad0fd7