[INFO] cloning repository https://github.com/flyingnobita/rustlings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/flyingnobita/rustlings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflyingnobita%2Frustlings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflyingnobita%2Frustlings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3f4b41939e672d8c450716c66e7fe0f67cda1bf3
[INFO] checking flyingnobita/rustlings against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflyingnobita%2Frustlings" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/flyingnobita/rustlings on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/flyingnobita/rustlings
[INFO] finished tweaking git repo https://github.com/flyingnobita/rustlings
[INFO] tweaked toml for git repo https://github.com/flyingnobita/rustlings written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/flyingnobita/rustlings 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 80d95cf8340ae3ef1d5bf4d4f0fa54b222538221399f016ab9c5b2570d4008d9
[INFO] running `Command { std: "docker" "start" "-a" "80d95cf8340ae3ef1d5bf4d4f0fa54b222538221399f016ab9c5b2570d4008d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "80d95cf8340ae3ef1d5bf4d4f0fa54b222538221399f016ab9c5b2570d4008d9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "80d95cf8340ae3ef1d5bf4d4f0fa54b222538221399f016ab9c5b2570d4008d9", kill_on_drop: false }`
[INFO] [stdout] 80d95cf8340ae3ef1d5bf4d4f0fa54b222538221399f016ab9c5b2570d4008d9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b400da8747de72fc672511138fef54c32152c439022d8c007d861060bf57c23f
[INFO] running `Command { std: "docker" "start" "-a" "b400da8747de72fc672511138fef54c32152c439022d8c007d861060bf57c23f", kill_on_drop: false }`
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking serde_json v1.0.66
[INFO] [stderr]     Checking console v0.15.0
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking escargot v0.4.0
[INFO] [stderr]     Checking indicatif v0.16.2
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Checking rustlings v4.7.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.84s
[INFO] running `Command { std: "docker" "inspect" "b400da8747de72fc672511138fef54c32152c439022d8c007d861060bf57c23f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b400da8747de72fc672511138fef54c32152c439022d8c007d861060bf57c23f", kill_on_drop: false }`
[INFO] [stdout] b400da8747de72fc672511138fef54c32152c439022d8c007d861060bf57c23f
[INFO] checking flyingnobita/rustlings against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fflyingnobita%2Frustlings" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/flyingnobita/rustlings on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/flyingnobita/rustlings
[INFO] finished tweaking git repo https://github.com/flyingnobita/rustlings
[INFO] tweaked toml for git repo https://github.com/flyingnobita/rustlings written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/flyingnobita/rustlings 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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d9666c51c05e9bfe36f19b13d8e85640f5e3e6b1c16c543ebe6b6b5c0792a5ff
[INFO] running `Command { std: "docker" "start" "-a" "d9666c51c05e9bfe36f19b13d8e85640f5e3e6b1c16c543ebe6b6b5c0792a5ff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d9666c51c05e9bfe36f19b13d8e85640f5e3e6b1c16c543ebe6b6b5c0792a5ff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d9666c51c05e9bfe36f19b13d8e85640f5e3e6b1c16c543ebe6b6b5c0792a5ff", kill_on_drop: false }`
[INFO] [stdout] d9666c51c05e9bfe36f19b13d8e85640f5e3e6b1c16c543ebe6b6b5c0792a5ff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9034f3af5b06f9f089a3deb6dce1b07d620fbacf748466f424d06316a2e22380
[INFO] running `Command { std: "docker" "start" "-a" "9034f3af5b06f9f089a3deb6dce1b07d620fbacf748466f424d06316a2e22380", kill_on_drop: false }`
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking serde_json v1.0.66
[INFO] [stderr]     Checking console v0.15.0
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking escargot v0.4.0
[INFO] [stderr]     Checking indicatif v0.16.2
[INFO] [stderr]     Checking rustlings v4.7.1 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.05s
[INFO] running `Command { std: "docker" "inspect" "9034f3af5b06f9f089a3deb6dce1b07d620fbacf748466f424d06316a2e22380", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9034f3af5b06f9f089a3deb6dce1b07d620fbacf748466f424d06316a2e22380", kill_on_drop: false }`
[INFO] [stdout] 9034f3af5b06f9f089a3deb6dce1b07d620fbacf748466f424d06316a2e22380