[INFO] fetching crate rclist 0.0.1...
[INFO] testing rclist-0.0.1 against 1.47.0 for beta-1.48-1
[INFO] extracting crate rclist 0.0.1 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate rclist 0.0.1 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", 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-1/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 95ef97a38eb802cdf5dfbadde6810097e01255c7093929b99ef8f8d9e5fd35a2
[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" "95ef97a38eb802cdf5dfbadde6810097e01255c7093929b99ef8f8d9e5fd35a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "95ef97a38eb802cdf5dfbadde6810097e01255c7093929b99ef8f8d9e5fd35a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "95ef97a38eb802cdf5dfbadde6810097e01255c7093929b99ef8f8d9e5fd35a2", kill_on_drop: false }`
[INFO] [stdout] 95ef97a38eb802cdf5dfbadde6810097e01255c7093929b99ef8f8d9e5fd35a2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4de9e5c2ec2c8c27310f3e30ca7da3ed54173dd59b5856abf17fb6762ab14b1f
[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" "4de9e5c2ec2c8c27310f3e30ca7da3ed54173dd59b5856abf17fb6762ab14b1f", 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 `&std::rc::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: `std::rc::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 `std::rc::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" "4de9e5c2ec2c8c27310f3e30ca7da3ed54173dd59b5856abf17fb6762ab14b1f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4de9e5c2ec2c8c27310f3e30ca7da3ed54173dd59b5856abf17fb6762ab14b1f", kill_on_drop: false }`
[INFO] [stdout] 4de9e5c2ec2c8c27310f3e30ca7da3ed54173dd59b5856abf17fb6762ab14b1f
