[INFO] fetching crate casperlabs-contract-ffi 0.18.0...
[INFO] checking casperlabs-contract-ffi-0.18.0 against beta-2019-10-27 for pr-65897
[INFO] extracting crate casperlabs-contract-ffi 0.18.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate casperlabs-contract-ffi 0.18.0 on toolchain beta-2019-10-27
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate casperlabs-contract-ffi 0.18.0
[INFO] finished tweaking crates.io crate casperlabs-contract-ffi 0.18.0
[INFO] tweaked toml for crates.io crate casperlabs-contract-ffi 0.18.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=allow" "-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-2019-10-27" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 8fce33f5af5370e052b5bcfdf043ef8c6347714e6055c02a0a6840bda27f842d
[INFO] running `"docker" "start" "-a" "8fce33f5af5370e052b5bcfdf043ef8c6347714e6055c02a0a6840bda27f842d"`
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling wee_alloc v0.4.5
[INFO] [stderr]     Checking memory_units v0.4.0
[INFO] [stderr]     Checking rustc-hex v2.0.1
[INFO] [stderr]     Checking binascii v0.1.2
[INFO] [stderr]     Checking siphasher v0.3.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking digest v0.8.1
[INFO] [stderr]     Checking failure v0.1.6
[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/rand_core-0.4.2/src/lib.rs:39:55
[INFO] [stderr]    |
[INFO] [stderr] 39 | #![cfg_attr(all(feature="alloc", not(feature="std")), feature(alloc))]
[INFO] [stderr]    |                                                       ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Checking blake2 v0.8.1
[INFO] [stderr]     Checking uint v0.7.1
[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 `rand_core`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "8fce33f5af5370e052b5bcfdf043ef8c6347714e6055c02a0a6840bda27f842d"`
[INFO] running `"docker" "rm" "-f" "8fce33f5af5370e052b5bcfdf043ef8c6347714e6055c02a0a6840bda27f842d"`
[INFO] [stdout] 8fce33f5af5370e052b5bcfdf043ef8c6347714e6055c02a0a6840bda27f842d