[INFO] updating cached repository https://github.com/michaelmelanson/wasm-kernel
[INFO] running `"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"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] fe497a1d55cf5915492ed3bf5b8b1b1b00f1f97d
[INFO] testing michaelmelanson/wasm-kernel against beta-2020-06-03 for beta-1.45-1
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmichaelmelanson%2Fwasm-kernel" "/workspace/builds/worker-0/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/michaelmelanson/wasm-kernel on toolchain beta-2020-06-03
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/michaelmelanson/wasm-kernel
[INFO] finished tweaking git repo https://github.com/michaelmelanson/wasm-kernel
[INFO] tweaked toml for git repo https://github.com/michaelmelanson/wasm-kernel written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/michaelmelanson/wasm-kernel already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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=warn" "-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" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-06-03" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 19b0376a2f19639a919d77d0958b2931afe7fb3730d884dc2b5a37db0ee293f7
[INFO] running `"docker" "start" "-a" "19b0376a2f19639a919d77d0958b2931afe7fb3730d884dc2b5a37db0ee293f7"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling syn v0.15.29
[INFO] [stderr]    Compiling byteorder v1.3.1
[INFO] [stderr]    Compiling ucs2 v0.1.0
[INFO] [stderr]    Compiling bit_field v0.9.0
[INFO] [stderr]    Compiling ux v0.1.3
[INFO] [stderr]    Compiling os_bootinfo v0.2.1
[INFO] [stderr]    Compiling usize_conversions v0.2.0
[INFO] [stderr]    Compiling libm v0.1.2
[INFO] [stderr]    Compiling memory_units v0.3.0
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/usize_conversions-0.2.0/src/lib.rs:6:1
[INFO] [stderr]   |
[INFO] [stderr] 6 | #![feature(i128_type)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `usize_conversions`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "19b0376a2f19639a919d77d0958b2931afe7fb3730d884dc2b5a37db0ee293f7"`
[INFO] running `"docker" "rm" "-f" "19b0376a2f19639a919d77d0958b2931afe7fb3730d884dc2b5a37db0ee293f7"`
[INFO] [stdout] 19b0376a2f19639a919d77d0958b2931afe7fb3730d884dc2b5a37db0ee293f7