[INFO] cloning repository https://github.com/clove335/write_OS_in_Rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/clove335/write_OS_in_Rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fclove335%2Fwrite_OS_in_Rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fclove335%2Fwrite_OS_in_Rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 12672620d8533fad3fe7831b37fece72be9e029f
[INFO] testing clove335/write_OS_in_Rust against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fclove335%2Fwrite_OS_in_Rust" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/clove335/write_OS_in_Rust on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-2/source/.cargo/config.toml
[INFO] started tweaking git repo https://github.com/clove335/write_OS_in_Rust
[INFO] removed 0 missing tests
[INFO] finished tweaking git repo https://github.com/clove335/write_OS_in_Rust
[INFO] tweaked toml for git repo https://github.com/clove335/write_OS_in_Rust written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/clove335/write_OS_in_Rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "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] 66a1b320d4d89ee008cc24a08ccaebe46ad04ee5512e18e2e0f13fd18bbee3c5
[INFO] running `Command { std: "docker" "start" "-a" "66a1b320d4d89ee008cc24a08ccaebe46ad04ee5512e18e2e0f13fd18bbee3c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "66a1b320d4d89ee008cc24a08ccaebe46ad04ee5512e18e2e0f13fd18bbee3c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "66a1b320d4d89ee008cc24a08ccaebe46ad04ee5512e18e2e0f13fd18bbee3c5", kill_on_drop: false }`
[INFO] [stdout] 66a1b320d4d89ee008cc24a08ccaebe46ad04ee5512e18e2e0f13fd18bbee3c5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3d634913b51028bbbbbec0f69881637d8723d38ba5b51392259410b513a0b6b9
[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" "3d634913b51028bbbbbec0f69881637d8723d38ba5b51392259410b513a0b6b9", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling x86_64 v0.14.3
[INFO] [stderr]    Compiling volatile v0.4.4
[INFO] [stderr]    Compiling bootloader v0.9.18
[INFO] [stderr]    Compiling volatile v0.2.7
[INFO] [stderr]    Compiling pc-keyboard v0.5.1
[INFO] [stderr]    Compiling lock_api v0.4.4
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/lock_api-0.4.4/src/lib.rs:91:34
[INFO] [stdout]    |
[INFO] [stdout] 91 | #![cfg_attr(feature = "nightly", feature(const_fn_trait_bound))]
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lock_api` 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" "3d634913b51028bbbbbec0f69881637d8723d38ba5b51392259410b513a0b6b9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3d634913b51028bbbbbec0f69881637d8723d38ba5b51392259410b513a0b6b9", kill_on_drop: false }`
[INFO] [stdout] 3d634913b51028bbbbbec0f69881637d8723d38ba5b51392259410b513a0b6b9