[INFO] cloning repository https://github.com/jcamposforner/Try-Catch-Rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jcamposforner/Try-Catch-Rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjcamposforner%2FTry-Catch-Rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjcamposforner%2FTry-Catch-Rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f11b6b9b36a6c7857c4f2de69807bfcda19c5b24
[INFO] checking jcamposforner/Try-Catch-Rust against try#9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840 for pr-149518
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjcamposforner%2FTry-Catch-Rust" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/jcamposforner/Try-Catch-Rust
[INFO] finished tweaking git repo https://github.com/jcamposforner/Try-Catch-Rust
[INFO] tweaked toml for git repo https://github.com/jcamposforner/Try-Catch-Rust written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/jcamposforner/Try-Catch-Rust on toolchain 9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/jcamposforner/Try-Catch-Rust 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" "+9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:94a0c148923f5b2b52a63ef0eeb1882ad339ab61bce784c8077cbe41c61feb6c" "/opt/rustwide/cargo-home/bin/cargo" "+9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a984cbcd70dcfdecc101627a607bc7a85657bd5ef93aca95c740c96bc830cb6e
[INFO] running `Command { std: "docker" "start" "-a" "a984cbcd70dcfdecc101627a607bc7a85657bd5ef93aca95c740c96bc830cb6e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a984cbcd70dcfdecc101627a607bc7a85657bd5ef93aca95c740c96bc830cb6e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a984cbcd70dcfdecc101627a607bc7a85657bd5ef93aca95c740c96bc830cb6e", kill_on_drop: false }`
[INFO] [stdout] a984cbcd70dcfdecc101627a607bc7a85657bd5ef93aca95c740c96bc830cb6e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:94a0c148923f5b2b52a63ef0eeb1882ad339ab61bce784c8077cbe41c61feb6c" "/opt/rustwide/cargo-home/bin/cargo" "+9b8307bcb9d1de8ffc7e1c81c48efffdb24ee840" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8ec30a775d54931bc1c35154dc3bdec86625d7c7d3a7fd4d56b7681000c492f4
[INFO] running `Command { std: "docker" "start" "-a" "8ec30a775d54931bc1c35154dc3bdec86625d7c7d3a7fd4d56b7681000c492f4", kill_on_drop: false }`
[INFO] [stderr]     Checking t v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     f.write(b"a");
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let _ = f.write(b"a");
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]  --> src/main.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 7 |     f.write(b"a");
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let _ = f.write(b"a");
[INFO] [stdout]   |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.11s
[INFO] running `Command { std: "docker" "inspect" "8ec30a775d54931bc1c35154dc3bdec86625d7c7d3a7fd4d56b7681000c492f4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8ec30a775d54931bc1c35154dc3bdec86625d7c7d3a7fd4d56b7681000c492f4", kill_on_drop: false }`
[INFO] [stdout] 8ec30a775d54931bc1c35154dc3bdec86625d7c7d3a7fd4d56b7681000c492f4