[INFO] cloning repository https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Flearn_rust_rustlings-8acebuzzy", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Flearn_rust_rustlings-8acebuzzy'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a931653ad28c0cfbfe51bdcf091197dc462032c4
[INFO] checking LearningOS/learn_rust_rustlings-8acebuzzy against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Flearn_rust_rustlings-8acebuzzy" "/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/LearningOS/learn_rust_rustlings-8acebuzzy 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/LearningOS/learn_rust_rustlings-8acebuzzy
[INFO] finished tweaking git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy
[INFO] tweaked toml for git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy 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-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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 397b93c9f14527d12ab883a82fdc5155728abf965edfea8da489960c0b139d2b
[INFO] running `Command { std: "docker" "start" "-a" "397b93c9f14527d12ab883a82fdc5155728abf965edfea8da489960c0b139d2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "397b93c9f14527d12ab883a82fdc5155728abf965edfea8da489960c0b139d2b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "397b93c9f14527d12ab883a82fdc5155728abf965edfea8da489960c0b139d2b", kill_on_drop: false }`
[INFO] [stdout] 397b93c9f14527d12ab883a82fdc5155728abf965edfea8da489960c0b139d2b
[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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] cfceae2a1b9cd37df1327cce99d3bd25d19ab99a69a1daea9fed71da7440a6c8
[INFO] running `Command { std: "docker" "start" "-a" "cfceae2a1b9cd37df1327cce99d3bd25d19ab99a69a1daea9fed71da7440a6c8", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]     Checking home v0.5.3
[INFO] [stderr]     Checking regex v1.5.5
[INFO] [stderr]     Checking console v0.15.0
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking indicatif v0.16.2
[INFO] [stderr]     Checking escargot v0.4.0
[INFO] [stderr]     Checking rustlings v4.8.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.41s
[INFO] running `Command { std: "docker" "inspect" "cfceae2a1b9cd37df1327cce99d3bd25d19ab99a69a1daea9fed71da7440a6c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cfceae2a1b9cd37df1327cce99d3bd25d19ab99a69a1daea9fed71da7440a6c8", kill_on_drop: false }`
[INFO] [stdout] cfceae2a1b9cd37df1327cce99d3bd25d19ab99a69a1daea9fed71da7440a6c8
[INFO] checking LearningOS/learn_rust_rustlings-8acebuzzy against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Flearn_rust_rustlings-8acebuzzy" "/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/LearningOS/learn_rust_rustlings-8acebuzzy 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/LearningOS/learn_rust_rustlings-8acebuzzy
[INFO] finished tweaking git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy
[INFO] tweaked toml for git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/LearningOS/learn_rust_rustlings-8acebuzzy 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-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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f69bdc7386d2c1b74dd30376d487d67ac1bd948a3a96514d9de3f1a138666311
[INFO] running `Command { std: "docker" "start" "-a" "f69bdc7386d2c1b74dd30376d487d67ac1bd948a3a96514d9de3f1a138666311", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f69bdc7386d2c1b74dd30376d487d67ac1bd948a3a96514d9de3f1a138666311", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f69bdc7386d2c1b74dd30376d487d67ac1bd948a3a96514d9de3f1a138666311", kill_on_drop: false }`
[INFO] [stdout] f69bdc7386d2c1b74dd30376d487d67ac1bd948a3a96514d9de3f1a138666311
[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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9332e4fe1f240d9b505d2cd79e6bbc2d92d95fb25eb2fb6ed114ba4308a5a85f
[INFO] running `Command { std: "docker" "start" "-a" "9332e4fe1f240d9b505d2cd79e6bbc2d92d95fb25eb2fb6ed114ba4308a5a85f", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde_json v1.0.81
[INFO] [stderr]     Checking home v0.5.3
[INFO] [stderr]     Checking regex v1.5.5
[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 v4.8.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.08s
[INFO] running `Command { std: "docker" "inspect" "9332e4fe1f240d9b505d2cd79e6bbc2d92d95fb25eb2fb6ed114ba4308a5a85f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9332e4fe1f240d9b505d2cd79e6bbc2d92d95fb25eb2fb6ed114ba4308a5a85f", kill_on_drop: false }`
[INFO] [stdout] 9332e4fe1f240d9b505d2cd79e6bbc2d92d95fb25eb2fb6ed114ba4308a5a85f