[INFO] fetching crate reverie-zk 0.2.1-rc.4...
[INFO] testing reverie-zk-0.2.1-rc.4 against 1.55.0 for beta-1.56-1
[INFO] extracting crate reverie-zk 0.2.1-rc.4 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate reverie-zk 0.2.1-rc.4 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] removed /workspace/builds/worker-13/source/rust-toolchain
[INFO] started tweaking crates.io crate reverie-zk 0.2.1-rc.4
[INFO] finished tweaking crates.io crate reverie-zk 0.2.1-rc.4
[INFO] tweaked toml for crates.io crate reverie-zk 0.2.1-rc.4 written to /workspace/builds/worker-13/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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] 9b303e6e35a801248cf68949b12609f0bfe421cb82d0ff1574e9d8e960a6f3c1
[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" "9b303e6e35a801248cf68949b12609f0bfe421cb82d0ff1574e9d8e960a6f3c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9b303e6e35a801248cf68949b12609f0bfe421cb82d0ff1574e9d8e960a6f3c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9b303e6e35a801248cf68949b12609f0bfe421cb82d0ff1574e9d8e960a6f3c1", kill_on_drop: false }`
[INFO] [stdout] 9b303e6e35a801248cf68949b12609f0bfe421cb82d0ff1574e9d8e960a6f3c1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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] e646a0b0188a1585b593ae3bceb94930c3f9469dc6265c0b7a811a9769f0bd9b
[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" "e646a0b0188a1585b593ae3bceb94930c3f9469dc6265c0b7a811a9769f0bd9b", kill_on_drop: false }`
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling sysinfo v0.15.9
[INFO] [stderr]    Compiling blake3 v0.3.8
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling futures-channel v0.3.17
[INFO] [stderr]    Compiling socket2 v0.4.1
[INFO] [stderr]    Compiling pin-project-internal v0.4.28
[INFO] [stderr]    Compiling crypto-mac v0.8.0
[INFO] [stderr]    Compiling serde-big-array v0.3.2
[INFO] [stderr]    Compiling bincode v1.3.3
[INFO] [stderr]    Compiling futures-util v0.3.17
[INFO] [stderr]    Compiling polling v2.1.0
[INFO] [stderr]    Compiling kv-log-macro v1.0.7
[INFO] [stderr]    Compiling async-io v1.6.0
[INFO] [stderr]    Compiling async-global-executor v2.0.2
[INFO] [stderr]    Compiling async-std v1.10.0
[INFO] [stderr]    Compiling pin-project v0.4.28
[INFO] [stderr]    Compiling futures-executor v0.3.17
[INFO] [stderr]    Compiling futures v0.3.17
[INFO] [stderr]    Compiling async-scoped v0.6.1
[INFO] [stderr]    Compiling reverie-zk v0.2.1-rc.4 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[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 `reverie-zk` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "e646a0b0188a1585b593ae3bceb94930c3f9469dc6265c0b7a811a9769f0bd9b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e646a0b0188a1585b593ae3bceb94930c3f9469dc6265c0b7a811a9769f0bd9b", kill_on_drop: false }`
[INFO] [stdout] e646a0b0188a1585b593ae3bceb94930c3f9469dc6265c0b7a811a9769f0bd9b