[INFO] fetching crate lark-collections 0.1.0...
[INFO] testing lark-collections-0.1.0 against 1.59.0 for beta-1.60-1
[INFO] extracting crate lark-collections 0.1.0 into /workspace/builds/worker-83/source
[INFO] validating manifest of crates.io crate lark-collections 0.1.0 on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lark-collections 0.1.0
[INFO] finished tweaking crates.io crate lark-collections 0.1.0
[INFO] tweaked toml for crates.io crate lark-collections 0.1.0 written to /workspace/builds/worker-83/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-83/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-83/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e90aa99693ebc74b227252757691e15ccc72e8a38f44c3142ca05153151a7371
[INFO] running `Command { std: "docker" "start" "-a" "e90aa99693ebc74b227252757691e15ccc72e8a38f44c3142ca05153151a7371", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e90aa99693ebc74b227252757691e15ccc72e8a38f44c3142ca05153151a7371", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e90aa99693ebc74b227252757691e15ccc72e8a38f44c3142ca05153151a7371", kill_on_drop: false }`
[INFO] [stdout] e90aa99693ebc74b227252757691e15ccc72e8a38f44c3142ca05153151a7371
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-83/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-83/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 25e473807cb3f26379aa35e9f43b0ca9b60a5ef6cfe0a1f479c1e4b94ecffde2
[INFO] running `Command { std: "docker" "start" "-a" "25e473807cb3f26379aa35e9f43b0ca9b60a5ef6cfe0a1f479c1e4b94ecffde2", kill_on_drop: false }`
[INFO] [stderr]    Compiling hashbrown v0.11.2
[INFO] [stderr]    Compiling rustc-hash v1.1.0
[INFO] [stderr]    Compiling indexmap v1.8.0
[INFO] [stderr]    Compiling lark-debug-with v0.1.0
[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/lark-debug-with-0.1.0/src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(box_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/lark-debug-with-0.1.0/src/lib.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(never_type)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/lark-debug-with-0.1.0/src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(in_band_lifetimes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/lark-debug-with-0.1.0/src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `lark-debug-with` due to 5 previous errors
[INFO] running `Command { std: "docker" "inspect" "25e473807cb3f26379aa35e9f43b0ca9b60a5ef6cfe0a1f479c1e4b94ecffde2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25e473807cb3f26379aa35e9f43b0ca9b60a5ef6cfe0a1f479c1e4b94ecffde2", kill_on_drop: false }`
[INFO] [stdout] 25e473807cb3f26379aa35e9f43b0ca9b60a5ef6cfe0a1f479c1e4b94ecffde2