[INFO] fetching crate image-decompose 0.4.1...
[INFO] testing image-decompose-0.4.1 against 1.55.0 for beta-1.56-1
[INFO] extracting crate image-decompose 0.4.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate image-decompose 0.4.1 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 image-decompose 0.4.1
[INFO] finished tweaking crates.io crate image-decompose 0.4.1
[INFO] tweaked toml for crates.io crate image-decompose 0.4.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate crates.io crate image-decompose 0.4.1 already has a lockfile, it will not be regenerated
[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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 08412d2da452695097f681c63ab10d3d7d113ea64b37560c885049d402231826
[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" "08412d2da452695097f681c63ab10d3d7d113ea64b37560c885049d402231826", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "08412d2da452695097f681c63ab10d3d7d113ea64b37560c885049d402231826", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "08412d2da452695097f681c63ab10d3d7d113ea64b37560c885049d402231826", kill_on_drop: false }`
[INFO] [stdout] 08412d2da452695097f681c63ab10d3d7d113ea64b37560c885049d402231826
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 305469ec6d007f048c665b210b136d47fa362ba168c72b92cd2f473fee8ed8fb
[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" "305469ec6d007f048c665b210b136d47fa362ba168c72b92cd2f473fee8ed8fb", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling weezl v0.1.4
[INFO] [stderr]    Compiling bytemuck v1.5.1
[INFO] [stderr]    Compiling os_str_bytes v2.4.0
[INFO] [stderr]    Compiling lab v0.9.0
[INFO] [stderr]    Compiling textwrap v0.12.1
[INFO] [stderr]    Compiling jobserver v0.1.21
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.3
[INFO] [stderr]    Compiling crossbeam-channel v0.5.0
[INFO] [stderr]    Compiling rgb_derivation v0.1.2
[INFO] [stderr]    Compiling rgb_derivation v0.2.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling num-bigint v0.4.0
[INFO] [stderr]    Compiling crossbeam-deque v0.8.0
[INFO] [stderr]    Compiling cc v1.0.67
[INFO] [stderr]    Compiling gif v0.11.2
[INFO] [stderr]    Compiling rayon-core v1.9.0
[INFO] [stderr]    Compiling rayon v1.5.0
[INFO] [stderr]    Compiling libwebp-sys v0.2.0
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling num v0.4.0
[INFO] [stderr]    Compiling srgb v0.1.4
[INFO] [stderr]    Compiling srgb v0.2.0
[INFO] [stderr]    Compiling jpeg-decoder v0.1.22
[INFO] [stderr]    Compiling tiff v0.6.1
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling luv v0.9.0
[INFO] [stderr]    Compiling image v0.23.14
[INFO] [stderr]    Compiling clap_derive v3.0.0-beta.2
[INFO] [stderr]    Compiling clap v3.0.0-beta.2
[INFO] [stderr]    Compiling webp v0.1.1
[INFO] [stderr]    Compiling image-decompose v0.4.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | / #![feature(
[INFO] [stdout] 2 | |     maybe_uninit_write_slice,
[INFO] [stdout] 3 | |     process_exitcode_placeholder,
[INFO] [stdout] 4 | |     result_into_ok_or_err,
[INFO] [stdout] ... |
[INFO] [stdout] 7 | |     vec_into_raw_parts
[INFO] [stdout] 8 | | )]
[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 `image-decompose` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "305469ec6d007f048c665b210b136d47fa362ba168c72b92cd2f473fee8ed8fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "305469ec6d007f048c665b210b136d47fa362ba168c72b92cd2f473fee8ed8fb", kill_on_drop: false }`
[INFO] [stdout] 305469ec6d007f048c665b210b136d47fa362ba168c72b92cd2f473fee8ed8fb