[INFO] fetching crate ramp-api 0.2.3...
[INFO] testing ramp-api-0.2.3 against 1.55.0 for beta-1.56-1
[INFO] extracting crate ramp-api 0.2.3 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate ramp-api 0.2.3 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 ramp-api 0.2.3
[INFO] finished tweaking crates.io crate ramp-api 0.2.3
[INFO] tweaked toml for crates.io crate ramp-api 0.2.3 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] 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] 5d773f99e5a0e6a7969f88e11bf268601386927425c561e8690297ff1b46aae9
[INFO] running `Command { std: "docker" "start" "-a" "5d773f99e5a0e6a7969f88e11bf268601386927425c561e8690297ff1b46aae9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5d773f99e5a0e6a7969f88e11bf268601386927425c561e8690297ff1b46aae9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d773f99e5a0e6a7969f88e11bf268601386927425c561e8690297ff1b46aae9", kill_on_drop: false }`
[INFO] [stdout] 5d773f99e5a0e6a7969f88e11bf268601386927425c561e8690297ff1b46aae9
[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] e613aa8440bc1f489bf7b2b8f5f0f31f371adac1500cd556fae06522594f8dae
[INFO] running `Command { std: "docker" "start" "-a" "e613aa8440bc1f489bf7b2b8f5f0f31f371adac1500cd556fae06522594f8dae", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling futures-task v0.3.17
[INFO] [stderr]    Compiling httparse v1.3.6
[INFO] [stderr]    Compiling schemars v0.8.3
[INFO] [stderr]    Compiling hyperx v1.2.0
[INFO] [stderr]    Compiling ipnet v2.3.1
[INFO] [stderr]    Compiling tokio v1.11.0
[INFO] [stderr]    Compiling futures-util v0.3.17
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling ring v0.16.20
[INFO] [stderr]    Compiling tracing v0.1.26
[INFO] [stderr]    Compiling http-body v0.4.3
[INFO] [stderr]    Compiling mio v0.7.13
[INFO] [stderr]    Compiling futures-channel v0.3.17
[INFO] [stderr]    Compiling socket2 v0.4.1
[INFO] [stderr]    Compiling pem v0.8.3
[INFO] [stderr]    Compiling serde_derive_internals v0.25.0
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]    Compiling tokio-macros v1.3.0
[INFO] [stderr]    Compiling pin-project-internal v1.0.8
[INFO] [stderr]    Compiling schemars_derive v0.8.3
[INFO] [stderr]    Compiling async-recursion v0.3.2
[INFO] [stderr]    Compiling pin-project v1.0.8
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling tokio-util v0.6.8
[INFO] [stderr]    Compiling tokio-native-tls v0.3.0
[INFO] [stderr]    Compiling h2 v0.3.4
[INFO] [stderr]    Compiling serde_json v1.0.67
[INFO] [stderr]    Compiling chrono v0.4.19
[INFO] [stderr]    Compiling uuid v0.8.2
[INFO] [stderr]    Compiling serde_urlencoded v0.7.0
[INFO] [stderr]    Compiling simple_asn1 v0.4.1
[INFO] [stderr]    Compiling hyper v0.14.5
[INFO] [stderr]    Compiling jsonwebtoken v7.2.0
[INFO] [stderr]    Compiling hyper-tls v0.5.0
[INFO] [stderr]    Compiling reqwest v0.11.4
[INFO] [stderr]    Compiling ramp-api v0.2.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:88:1
[INFO] [stdout]    |
[INFO] [stdout] 88 | #![feature(async_stream)]
[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 `ramp-api` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "e613aa8440bc1f489bf7b2b8f5f0f31f371adac1500cd556fae06522594f8dae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e613aa8440bc1f489bf7b2b8f5f0f31f371adac1500cd556fae06522594f8dae", kill_on_drop: false }`
[INFO] [stdout] e613aa8440bc1f489bf7b2b8f5f0f31f371adac1500cd556fae06522594f8dae