[INFO] cloning repository https://github.com/arusso/rust-grrs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/arusso/rust-grrs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Farusso%2Frust-grrs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Farusso%2Frust-grrs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5788e99154ba3223b0707733556b8bcc8628b556
[INFO] checking arusso/rust-grrs against master#642c19bfc3a5c1de985bf5d0cc8207ac9d22708a for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Farusso%2Frust-grrs" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/arusso/rust-grrs
[INFO] finished tweaking git repo https://github.com/arusso/rust-grrs
[INFO] tweaked toml for git repo https://github.com/arusso/rust-grrs written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/arusso/rust-grrs on toolchain 642c19bfc3a5c1de985bf5d0cc8207ac9d22708a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/arusso/rust-grrs 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" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded proc-macro2 v1.0.17
[INFO] [stderr]   Downloaded structopt-derive v0.4.7
[INFO] [stderr]   Downloaded structopt v0.3.14
[INFO] [stderr]   Downloaded exitfailure v0.5.1
[INFO] [stderr]   Downloaded syn v1.0.25
[INFO] [stderr]   Downloaded addr2line v0.12.1
[INFO] [stderr]   Downloaded backtrace v0.3.48
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 210989fa6da8f6da213fac69544b053e1f3b91b05640abdf082724cac4b2f32b
[INFO] running `Command { std: "docker" "start" "-a" "210989fa6da8f6da213fac69544b053e1f3b91b05640abdf082724cac4b2f32b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "210989fa6da8f6da213fac69544b053e1f3b91b05640abdf082724cac4b2f32b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "210989fa6da8f6da213fac69544b053e1f3b91b05640abdf082724cac4b2f32b", kill_on_drop: false }`
[INFO] [stdout] 210989fa6da8f6da213fac69544b053e1f3b91b05640abdf082724cac4b2f32b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+642c19bfc3a5c1de985bf5d0cc8207ac9d22708a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0b3047c79e5000659c32f1b297889e48dd8add90c6c04701bda1d91dba99dbdf
[INFO] running `Command { std: "docker" "start" "-a" "0b3047c79e5000659c32f1b297889e48dd8add90c6c04701bda1d91dba99dbdf", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.17
[INFO] [stderr]    Compiling syn v1.0.25
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]     Checking gimli v0.21.0
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]     Checking object v0.19.0
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.2
[INFO] [stderr]    Compiling proc-macro-error v1.0.2
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.1
[INFO] [stderr]     Checking addr2line v0.12.1
[INFO] [stderr]     Checking backtrace v0.3.48
[INFO] [stderr]    Compiling syn-mid v0.5.0
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking exitfailure v0.5.1
[INFO] [stderr]    Compiling structopt-derive v0.4.7
[INFO] [stderr]     Checking structopt v0.3.14
[INFO] [stderr]     Checking grrs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             writeln!(writer, "{}", line);
[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] 35 |             let _ = writeln!(writer, "{}", line);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:35:13
[INFO] [stdout]    |
[INFO] [stdout] 35 |             writeln!(writer, "{}", line);
[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] 35 |             let _ = writeln!(writer, "{}", line);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 12.09s
[INFO] running `Command { std: "docker" "inspect" "0b3047c79e5000659c32f1b297889e48dd8add90c6c04701bda1d91dba99dbdf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0b3047c79e5000659c32f1b297889e48dd8add90c6c04701bda1d91dba99dbdf", kill_on_drop: false }`
[INFO] [stdout] 0b3047c79e5000659c32f1b297889e48dd8add90c6c04701bda1d91dba99dbdf