[INFO] fetching crate tree_view 0.1.2...
[INFO] testing tree_view-0.1.2 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate tree_view 0.1.2 into /workspace/builds/worker-7-tc2/source
[INFO] started tweaking crates.io crate tree_view 0.1.2
[INFO] finished tweaking crates.io crate tree_view 0.1.2
[INFO] tweaked toml for crates.io crate tree_view 0.1.2 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate tree_view 0.1.2 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] crate crates.io crate tree_view 0.1.2 already has a lockfile, it will not be regenerated
[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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 5316ff5570198efcc2e291a5eba1ae4e40e756cf3eac31a886f4a99e2cfb7805
[INFO] running `Command { std: "docker" "start" "-a" "5316ff5570198efcc2e291a5eba1ae4e40e756cf3eac31a886f4a99e2cfb7805", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5316ff5570198efcc2e291a5eba1ae4e40e756cf3eac31a886f4a99e2cfb7805", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5316ff5570198efcc2e291a5eba1ae4e40e756cf3eac31a886f4a99e2cfb7805", kill_on_drop: false }`
[INFO] [stdout] 5316ff5570198efcc2e291a5eba1ae4e40e756cf3eac31a886f4a99e2cfb7805
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 894c8af051adc90c2308fe37681acedd0f21a29e982ab453a4814f0a3ba5b576
[INFO] running `Command { std: "docker" "start" "-a" "894c8af051adc90c2308fe37681acedd0f21a29e982ab453a4814f0a3ba5b576", kill_on_drop: false }`
[INFO] [stderr]    Compiling tree_view v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(allocator_api)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tree_view` (bin "tree_view_test") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "894c8af051adc90c2308fe37681acedd0f21a29e982ab453a4814f0a3ba5b576", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "894c8af051adc90c2308fe37681acedd0f21a29e982ab453a4814f0a3ba5b576", kill_on_drop: false }`
[INFO] [stdout] 894c8af051adc90c2308fe37681acedd0f21a29e982ab453a4814f0a3ba5b576
