[INFO] fetching crate nimiq-metrics-server 0.2.0...
[INFO] testing nimiq-metrics-server-0.2.0 against beta-2020-06-03 for beta-1.45-1
[INFO] extracting crate nimiq-metrics-server 0.2.0 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate nimiq-metrics-server 0.2.0 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 crates.io crate nimiq-metrics-server 0.2.0
[INFO] finished tweaking crates.io crate nimiq-metrics-server 0.2.0
[INFO] tweaked toml for crates.io crate nimiq-metrics-server 0.2.0 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+beta-2020-06-03" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] 7039355c9fdc21d518765082ce611461fd3faa4abf4b1a416ebe3ceabcbcfc32
[INFO] running `"docker" "start" "-a" "7039355c9fdc21d518765082ce611461fd3faa4abf4b1a416ebe3ceabcbcfc32"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling nimiq-collections v0.2.0
[INFO] [stderr]    Compiling weak-table v0.2.3
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling arrayvec v0.4.12
[INFO] [stderr]    Compiling encoding_rs v0.8.23
[INFO] [stderr]    Compiling libargon2-sys v0.2.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling clear_on_drop v0.2.3
[INFO] [stderr]    Compiling idna v0.2.0
[INFO] [stderr]    Compiling error-chain v0.12.2
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]    Compiling want v0.2.0
[INFO] [stderr]    Compiling fs2 v0.4.3
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]    Compiling liblmdb-sys v0.2.2
[INFO] [stderr]    Compiling syn v0.11.11
[INFO] [stderr]    Compiling lock_api v0.1.5
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[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/nimiq-collections-0.2.0/src/lib.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![feature(box_into_raw_non_null)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[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/nimiq-collections-0.2.0/src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(specialization)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: could not compile `nimiq-collections`.
[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" "7039355c9fdc21d518765082ce611461fd3faa4abf4b1a416ebe3ceabcbcfc32"`
[INFO] running `"docker" "rm" "-f" "7039355c9fdc21d518765082ce611461fd3faa4abf4b1a416ebe3ceabcbcfc32"`
[INFO] [stdout] 7039355c9fdc21d518765082ce611461fd3faa4abf4b1a416ebe3ceabcbcfc32