[INFO] cloning repository https://github.com/BigBillZhao/xv6-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/BigBillZhao/xv6-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBigBillZhao%2Fxv6-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBigBillZhao%2Fxv6-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 90dd3816def980313ad2b7b63649f1c9d502216c
[INFO] checking BigBillZhao/xv6-rust against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBigBillZhao%2Fxv6-rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/BigBillZhao/xv6-rust on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-4/source/.cargo/config.toml
[INFO] removed /workspace/builds/worker-4/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/BigBillZhao/xv6-rust
[INFO] finished tweaking git repo https://github.com/BigBillZhao/xv6-rust
[INFO] tweaked toml for git repo https://github.com/BigBillZhao/xv6-rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/BigBillZhao/xv6-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8f3cd4067a5e68ba718332033a24f5eb4c5494687b1ceeb851374a00795d0936
[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" "8f3cd4067a5e68ba718332033a24f5eb4c5494687b1ceeb851374a00795d0936", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8f3cd4067a5e68ba718332033a24f5eb4c5494687b1ceeb851374a00795d0936", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8f3cd4067a5e68ba718332033a24f5eb4c5494687b1ceeb851374a00795d0936", kill_on_drop: false }`
[INFO] [stdout] 8f3cd4067a5e68ba718332033a24f5eb4c5494687b1ceeb851374a00795d0936
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 756a2c172c6ed9099572700da42631bb15fb4ab5439e28db9a002776054e8ec8
[INFO] running `Command { std: "docker" "start" "-a" "756a2c172c6ed9099572700da42631bb15fb4ab5439e28db9a002776054e8ec8", kill_on_drop: false }`
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking spin v0.4.10
[INFO] [stderr]     Checking array-macro v2.0.0
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.10/src/lib.rs:6:43
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stdout]   |                                           ^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: split into finer-grained feature gates
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0557`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `spin` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "756a2c172c6ed9099572700da42631bb15fb4ab5439e28db9a002776054e8ec8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "756a2c172c6ed9099572700da42631bb15fb4ab5439e28db9a002776054e8ec8", kill_on_drop: false }`
[INFO] [stdout] 756a2c172c6ed9099572700da42631bb15fb4ab5439e28db9a002776054e8ec8