[INFO] updating cached repository https://github.com/AlexW-GH/rustos
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 91ec2179b3a501c093840ea22b34ec887910721c
[INFO] testing AlexW-GH/rustos against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAlexW-GH%2Frustos" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/AlexW-GH/rustos on toolchain 8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/AlexW-GH/rustos
[INFO] finished tweaking git repo https://github.com/AlexW-GH/rustos
[INFO] tweaked toml for git repo https://github.com/AlexW-GH/rustos written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/AlexW-GH/rustos already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] c798570e3db1c6e5aca4c78e17af6eb1ffd5899053280d192d7fbdf7242f7bed
[INFO] running `Command { std: "docker" "start" "-a" "c798570e3db1c6e5aca4c78e17af6eb1ffd5899053280d192d7fbdf7242f7bed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c798570e3db1c6e5aca4c78e17af6eb1ffd5899053280d192d7fbdf7242f7bed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c798570e3db1c6e5aca4c78e17af6eb1ffd5899053280d192d7fbdf7242f7bed", kill_on_drop: false }`
[INFO] [stdout] c798570e3db1c6e5aca4c78e17af6eb1ffd5899053280d192d7fbdf7242f7bed
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e1795f3af12c14486384d6591828a626b7030a9048665c7375179d417db25270
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e1795f3af12c14486384d6591828a626b7030a9048665c7375179d417db25270", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rlibc v1.0.0
[INFO] [stderr]    Compiling rustos v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0522]: definition of an unknown language item: `panic_fmt`
[INFO] [stdout]   --> src/lib.rs:24:1
[INFO] [stdout]    |
[INFO] [stdout] 24 | #[lang = "panic_fmt"] #[no_mangle] pub extern fn panic_fmt() -> ! {loop{}}
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^ definition of unknown language item `panic_fmt`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `#[panic_handler]` function required, but not found
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0522`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rustos`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "e1795f3af12c14486384d6591828a626b7030a9048665c7375179d417db25270", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e1795f3af12c14486384d6591828a626b7030a9048665c7375179d417db25270", kill_on_drop: false }`
[INFO] [stdout] e1795f3af12c14486384d6591828a626b7030a9048665c7375179d417db25270