[INFO] cloning repository https://github.com/dvc94ch/rust-ipld-collections
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dvc94ch/rust-ipld-collections" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdvc94ch%2Frust-ipld-collections"`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdvc94ch%2Frust-ipld-collections'...
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 789cd4e0e834bd199a365265866e1a39f4b00bba
[INFO] checking dvc94ch/rust-ipld-collections against beta-2019-10-27 for pr-65897
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdvc94ch%2Frust-ipld-collections" "/workspace/builds/worker-14/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-14/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dvc94ch/rust-ipld-collections 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 git repo https://github.com/dvc94ch/rust-ipld-collections
[INFO] finished tweaking git repo https://github.com/dvc94ch/rust-ipld-collections
[INFO] tweaked toml for git repo https://github.com/dvc94ch/rust-ipld-collections written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate git repo https://github.com/dvc94ch/rust-ipld-collections already has a lockfile, it will not be regenerated
[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-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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] [stdout] 6f21df6b58470b1dda360660c1ff606be657e91bfeb57dae20059021461e6472
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "6f21df6b58470b1dda360660c1ff606be657e91bfeb57dae20059021461e6472"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling integer-encoding v1.0.7
[INFO] [stderr]     Checking base-x v0.2.5
[INFO] [stderr]     Checking wait-timeout v0.2.0
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stderr]     Checking xoroshiro128 v0.3.0
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking crypto-mac v0.7.0
[INFO] [stderr]     Checking bstr v0.2.8
[INFO] [stderr]     Checking sha3 v0.8.2
[INFO] [stderr]     Checking sha2 v0.8.0
[INFO] [stderr]     Checking sha-1 v0.8.1
[INFO] [stderr]     Checking rand_os v0.2.2
[INFO] [stderr]     Checking rand_xoshiro v0.3.1
[INFO] [stderr]     Checking tinytemplate v1.0.2
[INFO] [stderr]     Checking rusty-fork v0.2.2
[INFO] [stderr]     Checking blake2 v0.8.1
[INFO] [stderr]     Checking fasthash v0.4.0
[INFO] [stderr]     Checking multibase v0.6.0 (https://github.com/multiformats/rust-multibase#f22326bc)
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling multihash_derive v0.1.0 (https://github.com/dvc94ch/rust-multihash?branch=cli#5ac35cd7)
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking csv v1.1.1
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]     Checking proptest v0.8.7
[INFO] [stderr]     Checking multihash v0.8.1-pre (https://github.com/dvc94ch/rust-multihash?branch=cli#5ac35cd7)
[INFO] [stderr]     Checking cid v0.3.1 (https://github.com/dvc94ch/rust-cid?branch=cli#52c079b2)
[INFO] [stderr]    Compiling synstructure v0.12.0
[INFO] [stderr]     Checking model v0.1.2
[INFO] [stderr]    Compiling proc-macro-hack v0.5.9
[INFO] [stderr]    Compiling async-trait v0.1.13
[INFO] [stderr]    Compiling serde_derive v1.0.101
[INFO] [stderr]    Compiling futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking libipld-base v0.1.0 (https://github.com/dvc94ch/rust-ipld#195df890)
[INFO] [stderr]    Compiling dag-cbor-derive v0.1.0 (https://github.com/dvc94ch/rust-ipld#195df890)
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking libipld-macro v0.1.0 (https://github.com/dvc94ch/rust-ipld#195df890)
[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/futures-util-preview-0.3.0-alpha.18/src/lib.rs:4:38
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![cfg_attr(feature = "async-await", feature(async_await))]
[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 `futures-util-preview`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "6f21df6b58470b1dda360660c1ff606be657e91bfeb57dae20059021461e6472"`
[INFO] running `"docker" "rm" "-f" "6f21df6b58470b1dda360660c1ff606be657e91bfeb57dae20059021461e6472"`
[INFO] [stdout] 6f21df6b58470b1dda360660c1ff606be657e91bfeb57dae20059021461e6472