[INFO] cloning repository https://github.com/nomorethirst/utf8-stats
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nomorethirst/utf8-stats" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnomorethirst%2Futf8-stats", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnomorethirst%2Futf8-stats'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 636ec5874e4166a94e3b91d4a84351c54a007dc3
[INFO] building nomorethirst/utf8-stats against try#d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6 for pr-146237-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnomorethirst%2Futf8-stats" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/nomorethirst/utf8-stats
[INFO] finished tweaking git repo https://github.com/nomorethirst/utf8-stats
[INFO] tweaked toml for git repo https://github.com/nomorethirst/utf8-stats written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/nomorethirst/utf8-stats on toolchain d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/nomorethirst/utf8-stats 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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e97e0ffd60e2fa80949bdb4360015371d37b3a3eb555dffa4c350baf49d94eae
[INFO] running `Command { std: "docker" "start" "-a" "e97e0ffd60e2fa80949bdb4360015371d37b3a3eb555dffa4c350baf49d94eae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e97e0ffd60e2fa80949bdb4360015371d37b3a3eb555dffa4c350baf49d94eae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e97e0ffd60e2fa80949bdb4360015371d37b3a3eb555dffa4c350baf49d94eae", kill_on_drop: false }`
[INFO] [stdout] e97e0ffd60e2fa80949bdb4360015371d37b3a3eb555dffa4c350baf49d94eae
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1d30aeb53f5a96ee472a7a8219fc6d829db652f1c19b81ef2a98a5dfade4f166
[INFO] running `Command { std: "docker" "start" "-a" "1d30aeb53f5a96ee472a7a8219fc6d829db652f1c19b81ef2a98a5dfade4f166", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling unicode-segmentation v1.7.1
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling utf8-stats v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:50:17
[INFO] [stdout]    |
[INFO] [stdout] 50 |                 write!(s, " {:02X}", b);
[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] 50 |                 let _ = write!(s, " {:02X}", b);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.77s
[INFO] running `Command { std: "docker" "inspect" "1d30aeb53f5a96ee472a7a8219fc6d829db652f1c19b81ef2a98a5dfade4f166", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1d30aeb53f5a96ee472a7a8219fc6d829db652f1c19b81ef2a98a5dfade4f166", kill_on_drop: false }`
[INFO] [stdout] 1d30aeb53f5a96ee472a7a8219fc6d829db652f1c19b81ef2a98a5dfade4f166
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1163a6d6a1d61ac017d0d65dcc6458f5a393646769002480d324037434a43fd4
[INFO] running `Command { std: "docker" "start" "-a" "1163a6d6a1d61ac017d0d65dcc6458f5a393646769002480d324037434a43fd4", kill_on_drop: false }`
[INFO] [stderr]    Compiling utf8-stats v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:50:17
[INFO] [stdout]    |
[INFO] [stdout] 50 |                 write!(s, " {:02X}", b);
[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] 50 |                 let _ = write!(s, " {:02X}", b);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "1163a6d6a1d61ac017d0d65dcc6458f5a393646769002480d324037434a43fd4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1163a6d6a1d61ac017d0d65dcc6458f5a393646769002480d324037434a43fd4", kill_on_drop: false }`
[INFO] [stdout] 1163a6d6a1d61ac017d0d65dcc6458f5a393646769002480d324037434a43fd4