[INFO] fetching crate pupper 0.1.0...
[INFO] testing pupper-0.1.0 against 1.55.0 for beta-1.56-1
[INFO] extracting crate pupper 0.1.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate pupper 0.1.0 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 pupper 0.1.0
[INFO] finished tweaking crates.io crate pupper 0.1.0
[INFO] tweaked toml for crates.io crate pupper 0.1.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate pupper 0.1.0 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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 4c6e65699f97f8578533474d3902fca95ff815358c617e0efe7439b778a4cb14
[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" "4c6e65699f97f8578533474d3902fca95ff815358c617e0efe7439b778a4cb14", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4c6e65699f97f8578533474d3902fca95ff815358c617e0efe7439b778a4cb14", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c6e65699f97f8578533474d3902fca95ff815358c617e0efe7439b778a4cb14", kill_on_drop: false }`
[INFO] [stdout] 4c6e65699f97f8578533474d3902fca95ff815358c617e0efe7439b778a4cb14
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 47ab7baf07706a379f4c7129e09fb197e2b8be075840dc24ed8c4cbe71e9b61c
[INFO] running `Command { std: "docker" "start" "-a" "47ab7baf07706a379f4c7129e09fb197e2b8be075840dc24ed8c4cbe71e9b61c", kill_on_drop: false }`
[INFO] [stderr]    Compiling pupper v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib/lib.rs:72:1
[INFO] [stdout]    |
[INFO] [stdout] 72 | #![feature(const_evaluatable_checked, const_generics)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `const_evaluatable_checked` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]   --> src/lib/lib.rs:72:12
[INFO] [stdout]    |
[INFO] [stdout] 72 | #![feature(const_evaluatable_checked, const_generics)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]    = note: see issue #76560 <https://github.com/rust-lang/rust/issues/76560> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]   --> src/lib/lib.rs:72:39
[INFO] [stdout]    |
[INFO] [stdout] 72 | #![feature(const_evaluatable_checked, const_generics)]
[INFO] [stdout]    |                                       ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pupper` due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "47ab7baf07706a379f4c7129e09fb197e2b8be075840dc24ed8c4cbe71e9b61c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47ab7baf07706a379f4c7129e09fb197e2b8be075840dc24ed8c4cbe71e9b61c", kill_on_drop: false }`
[INFO] [stdout] 47ab7baf07706a379f4c7129e09fb197e2b8be075840dc24ed8c4cbe71e9b61c