[INFO] fetching crate rclist 0.0.1...
[INFO] testing rclist-0.0.1 against 1.54.0 for beta-1.55-1
[INFO] extracting crate rclist 0.0.1 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate rclist 0.0.1 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rclist 0.0.1
[INFO] finished tweaking crates.io crate rclist 0.0.1
[INFO] tweaked toml for crates.io crate rclist 0.0.1 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c48cbcfa1c018c4a99caab6a9090294b0fb97e3048f6b0b41c5614671a2f238b
[INFO] running `Command { std: "docker" "start" "-a" "c48cbcfa1c018c4a99caab6a9090294b0fb97e3048f6b0b41c5614671a2f238b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c48cbcfa1c018c4a99caab6a9090294b0fb97e3048f6b0b41c5614671a2f238b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c48cbcfa1c018c4a99caab6a9090294b0fb97e3048f6b0b41c5614671a2f238b", kill_on_drop: false }`
[INFO] [stdout] c48cbcfa1c018c4a99caab6a9090294b0fb97e3048f6b0b41c5614671a2f238b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 79bda9ead9ee5e38aa332f4779981786788b940eb923473dd22db1f0b38a0af5
[INFO] running `Command { std: "docker" "start" "-a" "79bda9ead9ee5e38aa332f4779981786788b940eb923473dd22db1f0b38a0af5", kill_on_drop: false }`
[INFO] [stderr]    Compiling rclist v0.0.1 (/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(core)]
[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:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(alloc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `downgrade` found for reference `&Rc<T>` in the current scope
[INFO] [stdout]   --> src/lib.rs:31:50
[INFO] [stdout]    |
[INFO] [stdout] 31 |             &Link::Strong(ref x) => Link::Weak(x.downgrade()),
[INFO] [stdout]    |                                                --^^^^^^^^^
[INFO] [stdout]    |                                                | |
[INFO] [stdout]    |                                                | this is an associated function, not a method
[INFO] [stdout]    |                                                help: use associated function syntax instead: `Rc::<T>::downgrade`
[INFO] [stdout]    |
[INFO] [stdout]    = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
[INFO] [stdout]    = note: the candidate is defined in an impl for the type `Rc<T>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rclist`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "79bda9ead9ee5e38aa332f4779981786788b940eb923473dd22db1f0b38a0af5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79bda9ead9ee5e38aa332f4779981786788b940eb923473dd22db1f0b38a0af5", kill_on_drop: false }`
[INFO] [stdout] 79bda9ead9ee5e38aa332f4779981786788b940eb923473dd22db1f0b38a0af5
