[INFO] cloning repository https://github.com/j127/rust_cli_book_grrs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/j127/rust_cli_book_grrs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj127%2Frust_cli_book_grrs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj127%2Frust_cli_book_grrs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1980cbd2f776d3f0ab2df6d80ec8a67c84242a82
[INFO] checking j127/rust_cli_book_grrs against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj127%2Frust_cli_book_grrs" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/j127/rust_cli_book_grrs on toolchain ceab6128fa48a616bfd3e3adf4bc80133b8ee223
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/j127/rust_cli_book_grrs
[INFO] finished tweaking git repo https://github.com/j127/rust_cli_book_grrs
[INFO] tweaked toml for git repo https://github.com/j127/rust_cli_book_grrs written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/j127/rust_cli_book_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" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded number_prefix v0.3.0
[INFO] [stderr]   Downloaded failure_derive v0.1.6
[INFO] [stderr]   Downloaded quote v0.6.13
[INFO] [stderr]   Downloaded structopt-derive v0.2.18
[INFO] [stderr]   Downloaded exitfailure v0.5.1
[INFO] [stderr]   Downloaded console v0.9.2
[INFO] [stderr]   Downloaded termios v0.3.1
[INFO] [stderr]   Downloaded winapi-util v0.1.3
[INFO] [stderr]   Downloaded env_logger v0.7.1
[INFO] [stderr]   Downloaded indicatif v0.14.0
[INFO] [stderr]   Downloaded backtrace v0.3.43
[INFO] [stderr]   Downloaded aho-corasick v0.7.8
[INFO] [stderr]   Downloaded regex-syntax v0.6.14
[INFO] [stderr]   Downloaded backtrace-sys v0.1.32
[INFO] [stderr]   Downloaded regex v1.3.4
[INFO] [stderr]   Downloaded clap v2.33.0
[INFO] [stderr]   Downloaded unicode-segmentation v1.6.0
[INFO] [stderr]   Downloaded syn v0.15.44
[INFO] [stderr]   Downloaded heck v0.3.1
[INFO] [stderr]   Downloaded failure v0.1.6
[INFO] [stderr]   Downloaded proc-macro2 v0.4.30
[INFO] [stderr]   Downloaded structopt v0.2.18
[INFO] [stderr]   Downloaded memchr v2.3.0
[INFO] [stderr]   Downloaded ansi_term v0.11.0
[INFO] [stderr]   Downloaded unicode-width v0.1.7
[INFO] [stderr]   Downloaded vec_map v0.8.1
[INFO] [stderr]   Downloaded unicode-xid v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5e5907118dce4de70ae9f429d98bd20db9031a5f957f48744d29f484d0030740
[INFO] running `Command { std: "docker" "start" "-a" "5e5907118dce4de70ae9f429d98bd20db9031a5f957f48744d29f484d0030740", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5e5907118dce4de70ae9f429d98bd20db9031a5f957f48744d29f484d0030740", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5e5907118dce4de70ae9f429d98bd20db9031a5f957f48744d29f484d0030740", kill_on_drop: false }`
[INFO] [stdout] 5e5907118dce4de70ae9f429d98bd20db9031a5f957f48744d29f484d0030740
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] aba8325cb7be39cd1972d380e2bdd7a4a515dcf7dabc3226b7e887eceb8a71a3
[INFO] running `Command { std: "docker" "start" "-a" "aba8325cb7be39cd1972d380e2bdd7a4a515dcf7dabc3226b7e887eceb8a71a3", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling proc-macro2 v1.0.8
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling memchr v2.3.0
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling syn v1.0.14
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking regex-syntax v0.6.14
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]     Checking number_prefix v0.3.0
[INFO] [stderr]     Checking termcolor v1.1.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]     Checking aho-corasick v0.7.8
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking backtrace v0.3.43
[INFO] [stderr]     Checking regex v1.3.4
[INFO] [stderr]     Checking console v0.9.2
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]    Compiling structopt-derive v0.2.18
[INFO] [stderr]     Checking indicatif v0.14.0
[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 grrs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `CustomError` is never constructed
[INFO] [stdout]   --> src/main.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | struct CustomError(String);
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `CustomError` is never constructed
[INFO] [stdout]   --> src/main.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 22 | struct CustomError(String);
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.05s
[INFO] running `Command { std: "docker" "inspect" "aba8325cb7be39cd1972d380e2bdd7a4a515dcf7dabc3226b7e887eceb8a71a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aba8325cb7be39cd1972d380e2bdd7a4a515dcf7dabc3226b7e887eceb8a71a3", kill_on_drop: false }`
[INFO] [stdout] aba8325cb7be39cd1972d380e2bdd7a4a515dcf7dabc3226b7e887eceb8a71a3
[INFO] checking j127/rust_cli_book_grrs against try#3a4bc97f6385a3aa300a4fd689b44350e54fd676 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj127%2Frust_cli_book_grrs" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/j127/rust_cli_book_grrs on toolchain 3a4bc97f6385a3aa300a4fd689b44350e54fd676
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/j127/rust_cli_book_grrs
[INFO] finished tweaking git repo https://github.com/j127/rust_cli_book_grrs
[INFO] tweaked toml for git repo https://github.com/j127/rust_cli_book_grrs written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/j127/rust_cli_book_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" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 73d77570ea2d191285083912ed7d82955a776244a7837185629c4a646667dda3
[INFO] running `Command { std: "docker" "start" "-a" "73d77570ea2d191285083912ed7d82955a776244a7837185629c4a646667dda3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "73d77570ea2d191285083912ed7d82955a776244a7837185629c4a646667dda3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "73d77570ea2d191285083912ed7d82955a776244a7837185629c4a646667dda3", kill_on_drop: false }`
[INFO] [stdout] 73d77570ea2d191285083912ed7d82955a776244a7837185629c4a646667dda3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+3a4bc97f6385a3aa300a4fd689b44350e54fd676" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1901d98e622ddd443b91a59f084493fea32effd641a12df5c5c079a8ac064755
[INFO] running `Command { std: "docker" "start" "-a" "1901d98e622ddd443b91a59f084493fea32effd641a12df5c5c079a8ac064755", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.66
[INFO] [stderr]    Compiling proc-macro2 v1.0.8
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling memchr v2.3.0
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling syn v1.0.14
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling failure_derive v0.1.6
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking regex-syntax v0.6.14
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]     Checking quick-error v1.2.3
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking humantime v1.3.0
[INFO] [stderr]     Checking termcolor v1.1.0
[INFO] [stderr]     Checking number_prefix v0.3.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]     Checking aho-corasick v0.7.8
[INFO] [stderr]    Compiling backtrace-sys v0.1.32
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking backtrace v0.3.43
[INFO] [stderr]     Checking regex v1.3.4
[INFO] [stdout] error[E0282]: type annotations needed
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/regex-1.3.4/src/exec.rs:836:13
[INFO] [stdout]     |
[INFO] [stdout] 836 | /             match dfa::Fsm::reverse(
[INFO] [stdout] 837 | |                 &self.ro.dfa_reverse,
[INFO] [stdout] 838 | |                 self.cache.value(),
[INFO] [stdout] 839 | |                 false,
[INFO] [stdout] ...   |
[INFO] [stdout] 850 | |                 Quit => return Some(Quit),
[INFO] [stdout] 851 | |             };
[INFO] [stdout]     | |_____________^ cannot infer type
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0282`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `regex` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "1901d98e622ddd443b91a59f084493fea32effd641a12df5c5c079a8ac064755", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1901d98e622ddd443b91a59f084493fea32effd641a12df5c5c079a8ac064755", kill_on_drop: false }`
[INFO] [stdout] 1901d98e622ddd443b91a59f084493fea32effd641a12df5c5c079a8ac064755