[INFO] cloning repository https://github.com/os2edu/rustlings-QishenChen
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/os2edu/rustlings-QishenChen" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fos2edu%2Frustlings-QishenChen", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fos2edu%2Frustlings-QishenChen'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8b44cfcc5296bb224a7d53d9324f63d9369f2b0b
[INFO] checking os2edu/rustlings-QishenChen against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fos2edu%2Frustlings-QishenChen" "/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/os2edu/rustlings-QishenChen 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/os2edu/rustlings-QishenChen
[INFO] finished tweaking git repo https://github.com/os2edu/rustlings-QishenChen
[INFO] tweaked toml for git repo https://github.com/os2edu/rustlings-QishenChen written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/os2edu/rustlings-QishenChen 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] 63cf38f83f3a1f302d65a75b6a230adb07c8b4c43c6897917bfd6140c3b0420b
[INFO] running `Command { std: "docker" "start" "-a" "63cf38f83f3a1f302d65a75b6a230adb07c8b4c43c6897917bfd6140c3b0420b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "63cf38f83f3a1f302d65a75b6a230adb07c8b4c43c6897917bfd6140c3b0420b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "63cf38f83f3a1f302d65a75b6a230adb07c8b4c43c6897917bfd6140c3b0420b", kill_on_drop: false }`
[INFO] [stdout] 63cf38f83f3a1f302d65a75b6a230adb07c8b4c43c6897917bfd6140c3b0420b
[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] 79b8ba2ac9abf4f5def292c806770ed1f9b69ef8b11f6c8a0ad59403cb31fae0
[INFO] running `Command { std: "docker" "start" "-a" "79b8ba2ac9abf4f5def292c806770ed1f9b69ef8b11f6c8a0ad59403cb31fae0", kill_on_drop: false }`
[INFO] [stderr]     Checking rustlings v5.2.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.31s
[INFO] running `Command { std: "docker" "inspect" "79b8ba2ac9abf4f5def292c806770ed1f9b69ef8b11f6c8a0ad59403cb31fae0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79b8ba2ac9abf4f5def292c806770ed1f9b69ef8b11f6c8a0ad59403cb31fae0", kill_on_drop: false }`
[INFO] [stdout] 79b8ba2ac9abf4f5def292c806770ed1f9b69ef8b11f6c8a0ad59403cb31fae0