[INFO] fetching crate ssb-client 0.3.1...
[INFO] testing ssb-client-0.3.1 against 1.55.0 for beta-1.56-1
[INFO] extracting crate ssb-client 0.3.1 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate ssb-client 0.3.1 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ssb-client 0.3.1
[INFO] finished tweaking crates.io crate ssb-client 0.3.1
[INFO] tweaked toml for crates.io crate ssb-client 0.3.1 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 352438163e59ec0839690962b1a1d659c1ef3ac3b9ab25f6ec189c268c79ea90
[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" "352438163e59ec0839690962b1a1d659c1ef3ac3b9ab25f6ec189c268c79ea90", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "352438163e59ec0839690962b1a1d659c1ef3ac3b9ab25f6ec189c268c79ea90", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "352438163e59ec0839690962b1a1d659c1ef3ac3b9ab25f6ec189c268c79ea90", kill_on_drop: false }`
[INFO] [stdout] 352438163e59ec0839690962b1a1d659c1ef3ac3b9ab25f6ec189c268c79ea90
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 54c7e32323a73986d874659d15826d9bfef38f880163158f6e310c9d6e019f9f
[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" "54c7e32323a73986d874659d15826d9bfef38f880163158f6e310c9d6e019f9f", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling futures v0.1.31
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling pkg-config v0.3.19
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling cc v1.0.70
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling ucd-util v0.1.8
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling slab v0.4.4
[INFO] [stderr]    Compiling utf8-ranges v1.0.4
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling serde_json v1.0.67
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling ordermap v0.3.5
[INFO] [stderr]    Compiling safemem v0.3.3
[INFO] [stderr]    Compiling itoa v0.4.8
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling thread_local v0.3.6
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling base64 v0.9.3
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling libsodium-sys v0.0.16
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]    Compiling smallvec v0.6.14
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling tokio-sync v0.1.8
[INFO] [stderr]    Compiling multi-producer-sink v0.3.0
[INFO] [stderr]    Compiling multi-consumer-stream v0.3.0
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling secret_handshake v4.0.0
[INFO] [stderr]    Compiling box_stream v0.4.0
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling mio v0.6.23
[INFO] [stderr]    Compiling tokio-executor v0.1.10
[INFO] [stderr]    Compiling crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling tokio-io v0.1.13
[INFO] [stderr]    Compiling tokio-timer v0.2.13
[INFO] [stderr]    Compiling tokio-current-thread v0.1.7
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling crossbeam-deque v0.7.4
[INFO] [stderr]    Compiling tokio-threadpool v0.1.18
[INFO] [stderr]    Compiling atm-io-utils v0.1.0
[INFO] [stderr]    Compiling tokio-codec v0.1.2
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling mio-uds v0.6.8
[INFO] [stderr]    Compiling packet-stream-codec v0.1.0
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling tokio-udp v0.1.6
[INFO] [stderr]    Compiling tokio-uds v0.2.7
[INFO] [stderr]    Compiling tokio-fs v0.1.7
[INFO] [stderr]    Compiling tokio v0.1.22
[INFO] [stderr]    Compiling env_logger v0.4.3
[INFO] [stderr]    Compiling quickcheck v0.5.0
[INFO] [stderr]    Compiling sodiumoxide v0.0.16
[INFO] [stderr]    Compiling atm-async-utils v0.1.2
[INFO] [stderr]    Compiling packet-stream v0.5.0
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/secret_handshake-4.0.0/src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(unique)]
[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 `secret_handshake` 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" "54c7e32323a73986d874659d15826d9bfef38f880163158f6e310c9d6e019f9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54c7e32323a73986d874659d15826d9bfef38f880163158f6e310c9d6e019f9f", kill_on_drop: false }`
[INFO] [stdout] 54c7e32323a73986d874659d15826d9bfef38f880163158f6e310c9d6e019f9f