[INFO] cloning repository https://github.com/mkdika/mkgrep
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mkdika/mkgrep" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmkdika%2Fmkgrep", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmkdika%2Fmkgrep'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] eabc5ddf191e2ca1149c94fb84c934a2e1620ad7
[INFO] checking mkdika/mkgrep against try#2278ef25f90817c20d6dd0d2da58a990eb6f53cb for pr-145108-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmkdika%2Fmkgrep" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/mkdika/mkgrep
[INFO] finished tweaking git repo https://github.com/mkdika/mkgrep
[INFO] tweaked toml for git repo https://github.com/mkdika/mkgrep written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/mkdika/mkgrep on toolchain 2278ef25f90817c20d6dd0d2da58a990eb6f53cb
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2278ef25f90817c20d6dd0d2da58a990eb6f53cb" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/mkdika/mkgrep 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" "+2278ef25f90817c20d6dd0d2da58a990eb6f53cb" "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 hermit-abi v0.1.6
[INFO] [stderr]   Downloaded structopt-derive v0.2.18
[INFO] [stderr]   Downloaded failure v0.1.6
[INFO] [stderr]   Downloaded failure_derive v0.1.6
[INFO] [stderr]   Downloaded exitfailure v0.5.1
[INFO] [stderr]   Downloaded proc-macro2 v1.0.7
[INFO] [stderr]   Downloaded backtrace v0.3.40
[INFO] [stderr]   Downloaded structopt v0.2.18
[INFO] [stderr]   Downloaded syn v1.0.13
[INFO] [stderr]   Downloaded backtrace-sys v0.1.32
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+2278ef25f90817c20d6dd0d2da58a990eb6f53cb" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 615f00c29d2a25008f499d901a81c340ba939055b4363685c4b4d5ef33d2056c
[INFO] running `Command { std: "docker" "start" "-a" "615f00c29d2a25008f499d901a81c340ba939055b4363685c4b4d5ef33d2056c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "615f00c29d2a25008f499d901a81c340ba939055b4363685c4b4d5ef33d2056c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "615f00c29d2a25008f499d901a81c340ba939055b4363685c4b4d5ef33d2056c", kill_on_drop: false }`
[INFO] [stdout] 615f00c29d2a25008f499d901a81c340ba939055b4363685c4b4d5ef33d2056c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+2278ef25f90817c20d6dd0d2da58a990eb6f53cb" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f7b11f12cedeb8e5259c4b2a02a87afea11d4e48186742603c5bb3b318296837
[INFO] running `Command { std: "docker" "start" "-a" "f7b11f12cedeb8e5259c4b2a02a87afea11d4e48186742603c5bb3b318296837", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling proc-macro2 v1.0.7
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking backtrace v0.3.40
[INFO] [stderr]    Compiling structopt-derive v0.2.18
[INFO] [stderr]    Compiling synstructure v0.12.3
[INFO] [stderr]     Checking structopt v0.2.18
[INFO] [stderr]     Checking failure v0.1.6
[INFO] [stderr]     Checking exitfailure v0.5.1
[INFO] [stderr]     Checking mkgrep v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |             writeln!(handle, "{}", 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] 28 |             let _ = writeln!(handle, "{}", line);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:13
[INFO] [stdout]    |
[INFO] [stdout] 28 |             writeln!(handle, "{}", 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] 28 |             let _ = writeln!(handle, "{}", line);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.26s
[INFO] running `Command { std: "docker" "inspect" "f7b11f12cedeb8e5259c4b2a02a87afea11d4e48186742603c5bb3b318296837", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f7b11f12cedeb8e5259c4b2a02a87afea11d4e48186742603c5bb3b318296837", kill_on_drop: false }`
[INFO] [stdout] f7b11f12cedeb8e5259c4b2a02a87afea11d4e48186742603c5bb3b318296837