[INFO] fetching crate crsp-base 0.2.0...
[INFO] testing crsp-base-0.2.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate crsp-base 0.2.0 into /workspace/builds/worker-68/source
[INFO] validating manifest of crates.io crate crsp-base 0.2.0 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 crsp-base 0.2.0
[INFO] finished tweaking crates.io crate crsp-base 0.2.0
[INFO] tweaked toml for crates.io crate crsp-base 0.2.0 written to /workspace/builds/worker-68/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] [stderr]     Blocking waiting for file lock on package cache
[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-68/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-68/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] 4e80900a8b5c9898cbc86576f07d4bfd3e12b6ebdf75131f8d091067d7fe752d
[INFO] running `Command { std: "docker" "start" "-a" "4e80900a8b5c9898cbc86576f07d4bfd3e12b6ebdf75131f8d091067d7fe752d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4e80900a8b5c9898cbc86576f07d4bfd3e12b6ebdf75131f8d091067d7fe752d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e80900a8b5c9898cbc86576f07d4bfd3e12b6ebdf75131f8d091067d7fe752d", kill_on_drop: false }`
[INFO] [stdout] 4e80900a8b5c9898cbc86576f07d4bfd3e12b6ebdf75131f8d091067d7fe752d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-68/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-68/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] 31727d941ad93580828cc5cdc4009be2fd2893cb1710fb0fa88f3b9a0e706b97
[INFO] running `Command { std: "docker" "start" "-a" "31727d941ad93580828cc5cdc4009be2fd2893cb1710fb0fa88f3b9a0e706b97", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.76
[INFO] [stderr]    Compiling libc v0.2.101
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling futures-core v0.3.17
[INFO] [stderr]    Compiling futures-sink v0.3.17
[INFO] [stderr]    Compiling convert_case v0.4.0
[INFO] [stderr]    Compiling pin-project-lite v0.2.7
[INFO] [stderr]    Compiling spin_sleep v1.0.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.29
[INFO] [stderr]    Compiling lock_api v0.4.5
[INFO] [stderr]    Compiling tracing-core v0.1.19
[INFO] [stderr]    Compiling spin v0.9.2
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling rand_core v0.6.3
[INFO] [stderr]    Compiling nanorand v0.6.1
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling toml v0.5.8
[INFO] [stderr]    Compiling rand v0.8.4
[INFO] [stderr]    Compiling thiserror-impl v1.0.29
[INFO] [stderr]    Compiling pin-project-internal v1.0.8
[INFO] [stderr]    Compiling derivative v2.2.0
[INFO] [stderr]    Compiling tracing-attributes v0.1.15
[INFO] [stderr]    Compiling derive_more v0.99.16
[INFO] [stderr]    Compiling tracing v0.1.26
[INFO] [stderr]    Compiling thiserror v1.0.29
[INFO] [stderr]    Compiling pin-project v1.0.8
[INFO] [stderr]    Compiling flume v0.10.9
[INFO] [stderr]    Compiling proc-macro-crate v1.0.0
[INFO] [stderr]    Compiling num_enum_derive v0.5.4
[INFO] [stderr]    Compiling num_enum v0.5.4
[INFO] [stderr]    Compiling crsp-base v0.2.0 (/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(variant_count, step_trait)]
[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 `crsp-base` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "31727d941ad93580828cc5cdc4009be2fd2893cb1710fb0fa88f3b9a0e706b97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31727d941ad93580828cc5cdc4009be2fd2893cb1710fb0fa88f3b9a0e706b97", kill_on_drop: false }`
[INFO] [stdout] 31727d941ad93580828cc5cdc4009be2fd2893cb1710fb0fa88f3b9a0e706b97