[INFO] cloning repository https://github.com/ShawnHuang/x86-kernel
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ShawnHuang/x86-kernel" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShawnHuang%2Fx86-kernel", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShawnHuang%2Fx86-kernel'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5a5ca5d8ff62fec24595a647a4160ca3e3e01cbf
[INFO] testing ShawnHuang/x86-kernel against master#62efba8a050c64249dab942951bb28f710208bc8 for pr-90799
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShawnHuang%2Fx86-kernel" "/workspace/builds/worker-87/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-87/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ShawnHuang/x86-kernel on toolchain 62efba8a050c64249dab942951bb28f710208bc8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/ShawnHuang/x86-kernel
[INFO] finished tweaking git repo https://github.com/ShawnHuang/x86-kernel
[INFO] tweaked toml for git repo https://github.com/ShawnHuang/x86-kernel written to /workspace/builds/worker-87/source/Cargo.toml
[INFO] crate git repo https://github.com/ShawnHuang/x86-kernel already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rlibc v0.1.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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:e8397a04204aaf8b9f284182a6f9e27a3c2e67044d0943b4415b160bfc957681" "/opt/rustwide/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] da882d54b1a3de1826d389834aa22a47725ab23d48a162d11d5108681d50341a
[INFO] running `Command { std: "docker" "start" "-a" "da882d54b1a3de1826d389834aa22a47725ab23d48a162d11d5108681d50341a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "da882d54b1a3de1826d389834aa22a47725ab23d48a162d11d5108681d50341a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da882d54b1a3de1826d389834aa22a47725ab23d48a162d11d5108681d50341a", kill_on_drop: false }`
[INFO] [stdout] da882d54b1a3de1826d389834aa22a47725ab23d48a162d11d5108681d50341a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-87/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" "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:e8397a04204aaf8b9f284182a6f9e27a3c2e67044d0943b4415b160bfc957681" "/opt/rustwide/cargo-home/bin/cargo" "+62efba8a050c64249dab942951bb28f710208bc8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 86a82e541f4287f841b5b08020c181a4300478932a6b2ead63c8c613894049a5
[INFO] running `Command { std: "docker" "start" "-a" "86a82e541f4287f841b5b08020c181a4300478932a6b2ead63c8c613894049a5", kill_on_drop: false }`
[INFO] [stderr]    Compiling rlibc v0.1.4
[INFO] [stderr]    Compiling my_os v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0152]: found duplicate lang item `panic_fmt`
[INFO] [stdout]   --> src/lib.rs:24:23
[INFO] [stdout]    |
[INFO] [stdout] 24 | #[lang = "panic_fmt"] extern fn panic_fmt() -> ! { loop{} }
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the lang item is first defined in crate `core` (which `my_os` depends on)
[INFO] [stdout]    = note: first definition in `core` loaded from /opt/rustwide/rustup-home/toolchains/62efba8a050c64249dab942951bb28f710208bc8/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-0e3656b1fda5fd7b.rlib
[INFO] [stdout]    = note: second definition in the local crate (`my_os`)
[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 E0152`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `my_os` due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "86a82e541f4287f841b5b08020c181a4300478932a6b2ead63c8c613894049a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "86a82e541f4287f841b5b08020c181a4300478932a6b2ead63c8c613894049a5", kill_on_drop: false }`
[INFO] [stdout] 86a82e541f4287f841b5b08020c181a4300478932a6b2ead63c8c613894049a5