[INFO] fetching crate untagged-option 0.2.0...
[INFO] testing untagged-option-0.2.0 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate untagged-option 0.2.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate untagged-option 0.2.0
[INFO] finished tweaking crates.io crate untagged-option 0.2.0
[INFO] tweaked toml for crates.io crate untagged-option 0.2.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate untagged-option 0.2.0 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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] f33f2a9c98d45665f4cbfa4246aea641c76d412c13f31cf24c5c8cbc64a18c06
[INFO] running `Command { std: "docker" "start" "-a" "f33f2a9c98d45665f4cbfa4246aea641c76d412c13f31cf24c5c8cbc64a18c06", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f33f2a9c98d45665f4cbfa4246aea641c76d412c13f31cf24c5c8cbc64a18c06", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f33f2a9c98d45665f4cbfa4246aea641c76d412c13f31cf24c5c8cbc64a18c06", kill_on_drop: false }`
[INFO] [stdout] f33f2a9c98d45665f4cbfa4246aea641c76d412c13f31cf24c5c8cbc64a18c06
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 89ea4f342fa927aaf225efe7398374f496fbaa8f6947e79014da710060381799
[INFO] running `Command { std: "docker" "start" "-a" "89ea4f342fa927aaf225efe7398374f496fbaa8f6947e79014da710060381799", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr]    Compiling untagged-option v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(untagged_unions)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: removed in 1.64.0; see <https://github.com/rust-lang/rust/pull/97995> for more information
[INFO] [stdout]   = note: unions with `Copy` and `ManuallyDrop` fields are stable; there is no intent to stabilize more
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unknown lint: `unions_with_drop_fields`
[INFO] [stdout]   --> src/lib.rs:51:9
[INFO] [stdout]    |
[INFO] [stdout] 51 | #[allow(unions_with_drop_fields)]
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unknown_lints)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0557`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `untagged-option` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "89ea4f342fa927aaf225efe7398374f496fbaa8f6947e79014da710060381799", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89ea4f342fa927aaf225efe7398374f496fbaa8f6947e79014da710060381799", kill_on_drop: false }`
[INFO] [stdout] 89ea4f342fa927aaf225efe7398374f496fbaa8f6947e79014da710060381799
