[INFO] cloning repository https://github.com/princemuel/rust_os
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/princemuel/rust_os" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprincemuel%2Frust_os", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprincemuel%2Frust_os'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4f1c944dca18da59ba4c3aeaff4edfdbff024dc9
[INFO] building princemuel/rust_os against try#d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6 for pr-146237-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprincemuel%2Frust_os" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/princemuel/rust_os
[INFO] finished tweaking git repo https://github.com/princemuel/rust_os
[INFO] tweaked toml for git repo https://github.com/princemuel/rust_os written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/princemuel/rust_os on toolchain d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/princemuel/rust_os 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" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 906bfb4d0c41caa0eb50d91fd61b4965244e31f47b1a8a5243bb709c25baaf82
[INFO] running `Command { std: "docker" "start" "-a" "906bfb4d0c41caa0eb50d91fd61b4965244e31f47b1a8a5243bb709c25baaf82", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "906bfb4d0c41caa0eb50d91fd61b4965244e31f47b1a8a5243bb709c25baaf82", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "906bfb4d0c41caa0eb50d91fd61b4965244e31f47b1a8a5243bb709c25baaf82", kill_on_drop: false }`
[INFO] [stdout] 906bfb4d0c41caa0eb50d91fd61b4965244e31f47b1a8a5243bb709c25baaf82
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+d79d87d4c0f7f0d0785ad6e493cf8cf718ed89a6" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a36b80a2200821c6f78efc9d04d0c426a688e83b6a550b063892872843cba095
[INFO] running `Command { std: "docker" "start" "-a" "a36b80a2200821c6f78efc9d04d0c426a688e83b6a550b063892872843cba095", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_os v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: `#[panic_handler]` function required, but not found
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: unwinding panics are not supported without std
[INFO] [stdout]   |
[INFO] [stdout]   = help: using nightly cargo, use -Zbuild-std with panic="abort" to avoid unwinding
[INFO] [stdout]   = note: since the core library is usually precompiled with panic="unwind", rebuilding your crate with panic="abort" may not be enough to fix the problem
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_os` (bin "rust_os") due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "a36b80a2200821c6f78efc9d04d0c426a688e83b6a550b063892872843cba095", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a36b80a2200821c6f78efc9d04d0c426a688e83b6a550b063892872843cba095", kill_on_drop: false }`
[INFO] [stdout] a36b80a2200821c6f78efc9d04d0c426a688e83b6a550b063892872843cba095