[INFO] fetching crate rclist 0.0.1...
[INFO] testing rclist-0.0.1 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate rclist 0.0.1 into /workspace/builds/worker-2-tc2/source
[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-2-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate rclist 0.0.1 on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 36b5e3aaa514b93391ab3216d3d7a2a3cdcc818d28e223a8d62d5636628239fe
[INFO] running `Command { std: "docker" "start" "-a" "36b5e3aaa514b93391ab3216d3d7a2a3cdcc818d28e223a8d62d5636628239fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "36b5e3aaa514b93391ab3216d3d7a2a3cdcc818d28e223a8d62d5636628239fe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "36b5e3aaa514b93391ab3216d3d7a2a3cdcc818d28e223a8d62d5636628239fe", kill_on_drop: false }`
[INFO] [stdout] 36b5e3aaa514b93391ab3216d3d7a2a3cdcc818d28e223a8d62d5636628239fe
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/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" "RUSTDOCFLAGS=--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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d15309fd5282890fe201d12f06f8ab8584e3aa1eff8e0d010e4554e10e3df68b
[INFO] running `Command { std: "docker" "start" "-a" "d15309fd5282890fe201d12f06f8ab8584e3aa1eff8e0d010e4554e10e3df68b", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr]    Compiling rclist v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(core)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `core` has been stable since 1.6.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(core)]
[INFO] [stdout]   |            ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `alloc` has been stable since 1.36.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:2:12
[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]    |                                                  ^^^^^^^^^ this is an associated function, not a method
[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, A>`
[INFO] [stdout] help: use associated function syntax instead
[INFO] [stdout]    |
[INFO] [stdout] 31 -             &Link::Strong(ref x) => Link::Weak(x.downgrade()),
[INFO] [stdout] 31 +             &Link::Strong(ref x) => Link::Weak(Rc::<T>::downgrade(&x)),
[INFO] [stdout]    |
[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` (lib) due to 2 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "d15309fd5282890fe201d12f06f8ab8584e3aa1eff8e0d010e4554e10e3df68b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d15309fd5282890fe201d12f06f8ab8584e3aa1eff8e0d010e4554e10e3df68b", kill_on_drop: false }`
[INFO] [stdout] d15309fd5282890fe201d12f06f8ab8584e3aa1eff8e0d010e4554e10e3df68b
