[INFO] fetching crate calf-vec 0.3.1-beta...
[INFO] testing calf-vec-0.3.1-beta against 1.55.0 for beta-1.56-1
[INFO] extracting crate calf-vec 0.3.1-beta into /workspace/builds/worker-66/source
[INFO] validating manifest of crates.io crate calf-vec 0.3.1-beta 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 calf-vec 0.3.1-beta
[INFO] finished tweaking crates.io crate calf-vec 0.3.1-beta
[INFO] tweaked toml for crates.io crate calf-vec 0.3.1-beta written to /workspace/builds/worker-66/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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-66/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-66/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] 79f188d68b508b35ebfd8133342971401f2ecd9309b5f034c8cef035eb464b58
[INFO] running `Command { std: "docker" "start" "-a" "79f188d68b508b35ebfd8133342971401f2ecd9309b5f034c8cef035eb464b58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "79f188d68b508b35ebfd8133342971401f2ecd9309b5f034c8cef035eb464b58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79f188d68b508b35ebfd8133342971401f2ecd9309b5f034c8cef035eb464b58", kill_on_drop: false }`
[INFO] [stdout] 79f188d68b508b35ebfd8133342971401f2ecd9309b5f034c8cef035eb464b58
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-66/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-66/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] 4d2a0f7e8789bd4a9a395acd41d484757a295d885a423bfe552c598e5a7cae4e
[INFO] running `Command { std: "docker" "start" "-a" "4d2a0f7e8789bd4a9a395acd41d484757a295d885a423bfe552c598e5a7cae4e", kill_on_drop: false }`
[INFO] [stderr]    Compiling calf-vec v0.3.1-beta (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:49:1
[INFO] [stdout]    |
[INFO] [stdout] 49 | #![feature(min_const_generics)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]    |
[INFO] [stdout]    = help: the feature `min_const_generics` has been stable since 1.51.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:50:1
[INFO] [stdout]    |
[INFO] [stdout] 50 | #![feature(untagged_unions)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:51:1
[INFO] [stdout]    |
[INFO] [stdout] 51 | #![feature(vec_into_raw_parts)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:52:1
[INFO] [stdout]    |
[INFO] [stdout] 52 | #![feature(slice_partition_dedup)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:53:1
[INFO] [stdout]    |
[INFO] [stdout] 53 | #![feature(shrink_to)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 5 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 `calf-vec` due to 6 previous errors
[INFO] running `Command { std: "docker" "inspect" "4d2a0f7e8789bd4a9a395acd41d484757a295d885a423bfe552c598e5a7cae4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d2a0f7e8789bd4a9a395acd41d484757a295d885a423bfe552c598e5a7cae4e", kill_on_drop: false }`
[INFO] [stdout] 4d2a0f7e8789bd4a9a395acd41d484757a295d885a423bfe552c598e5a7cae4e