[INFO] cloning repository https://github.com/jonnitg/rustlings-answers
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jonnitg/rustlings-answers" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjonnitg%2Frustlings-answers", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjonnitg%2Frustlings-answers'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6181337eafa02836d46d61e4911c2cb19342840c
[INFO] checking jonnitg/rustlings-answers against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjonnitg%2Frustlings-answers" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jonnitg/rustlings-answers 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/jonnitg/rustlings-answers
[INFO] finished tweaking git repo https://github.com/jonnitg/rustlings-answers
[INFO] tweaked toml for git repo https://github.com/jonnitg/rustlings-answers written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/jonnitg/rustlings-answers 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] 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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1ad3596c9850a96e5f1128cdedd8171ca3c6005a1e5202deaf16e4a71ffa4c93
[INFO] running `Command { std: "docker" "start" "-a" "1ad3596c9850a96e5f1128cdedd8171ca3c6005a1e5202deaf16e4a71ffa4c93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1ad3596c9850a96e5f1128cdedd8171ca3c6005a1e5202deaf16e4a71ffa4c93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ad3596c9850a96e5f1128cdedd8171ca3c6005a1e5202deaf16e4a71ffa4c93", kill_on_drop: false }`
[INFO] [stdout] 1ad3596c9850a96e5f1128cdedd8171ca3c6005a1e5202deaf16e4a71ffa4c93
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 817d362f8dc279f3d9bdafb65d7ba6e702be3bf48756c8dccd61df5ab314c7a0
[INFO] running `Command { std: "docker" "start" "-a" "817d362f8dc279f3d9bdafb65d7ba6e702be3bf48756c8dccd61df5ab314c7a0", kill_on_drop: false }`
[INFO] [stderr]     Checking rustlings v2.2.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.33s
[INFO] running `Command { std: "docker" "inspect" "817d362f8dc279f3d9bdafb65d7ba6e702be3bf48756c8dccd61df5ab314c7a0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "817d362f8dc279f3d9bdafb65d7ba6e702be3bf48756c8dccd61df5ab314c7a0", kill_on_drop: false }`
[INFO] [stdout] 817d362f8dc279f3d9bdafb65d7ba6e702be3bf48756c8dccd61df5ab314c7a0
[INFO] checking jonnitg/rustlings-answers against try#3a4bc97f6385a3aa300a4fd689b44350e54fd676 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjonnitg%2Frustlings-answers" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jonnitg/rustlings-answers 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/jonnitg/rustlings-answers
[INFO] finished tweaking git repo https://github.com/jonnitg/rustlings-answers
[INFO] tweaked toml for git repo https://github.com/jonnitg/rustlings-answers written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/jonnitg/rustlings-answers 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-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] d0a1ab61f51f808fb27fea19fc8478e829e357385f6c51397193de3ab93c7e2f
[INFO] running `Command { std: "docker" "start" "-a" "d0a1ab61f51f808fb27fea19fc8478e829e357385f6c51397193de3ab93c7e2f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d0a1ab61f51f808fb27fea19fc8478e829e357385f6c51397193de3ab93c7e2f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d0a1ab61f51f808fb27fea19fc8478e829e357385f6c51397193de3ab93c7e2f", kill_on_drop: false }`
[INFO] [stdout] d0a1ab61f51f808fb27fea19fc8478e829e357385f6c51397193de3ab93c7e2f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 4b8be3f928ff325b82b973004ca03793eeabbd73642bc7ac912f62414c66e252
[INFO] running `Command { std: "docker" "start" "-a" "4b8be3f928ff325b82b973004ca03793eeabbd73642bc7ac912f62414c66e252", kill_on_drop: false }`
[INFO] [stderr]     Checking regex v1.1.6
[INFO] [stderr]    Compiling serde_derive v1.0.92
[INFO] [stdout] error[E0282]: type annotations needed
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/regex-1.1.6/src/exec.rs:797:13
[INFO] [stdout]     |
[INFO] [stdout] 797 | /             match dfa::Fsm::reverse(
[INFO] [stdout] 798 | |                 &self.ro.dfa_reverse,
[INFO] [stdout] 799 | |                 self.cache,
[INFO] [stdout] 800 | |                 false,
[INFO] [stdout] ...   |
[INFO] [stdout] 811 | |                 Quit => return Some(Quit),
[INFO] [stdout] 812 | |             };
[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" "4b8be3f928ff325b82b973004ca03793eeabbd73642bc7ac912f62414c66e252", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b8be3f928ff325b82b973004ca03793eeabbd73642bc7ac912f62414c66e252", kill_on_drop: false }`
[INFO] [stdout] 4b8be3f928ff325b82b973004ca03793eeabbd73642bc7ac912f62414c66e252