[INFO] fetching crate panic-serial 0.1.2...
[INFO] testing panic-serial-0.1.2 against beta-2025-09-21 for beta-1.91-3
[INFO] extracting crate panic-serial 0.1.2 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate panic-serial 0.1.2
[INFO] finished tweaking crates.io crate panic-serial 0.1.2
[INFO] tweaked toml for crates.io crate panic-serial 0.1.2 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate panic-serial 0.1.2 on toolchain beta-2025-09-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "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-2025-09-21" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 7 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-09-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c80983dfd969595e55c32339071601168fa3672641d7df8808caf048202bb939
[INFO] running `Command { std: "docker" "start" "-a" "c80983dfd969595e55c32339071601168fa3672641d7df8808caf048202bb939", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c80983dfd969595e55c32339071601168fa3672641d7df8808caf048202bb939", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c80983dfd969595e55c32339071601168fa3672641d7df8808caf048202bb939", kill_on_drop: false }`
[INFO] [stdout] c80983dfd969595e55c32339071601168fa3672641d7df8808caf048202bb939
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-09-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 425d0e5a9d053a1493bd637493d88dc0bac64031120f6aa71cb805c52a4a650e
[INFO] running `Command { std: "docker" "start" "-a" "425d0e5a9d053a1493bd637493d88dc0bac64031120f6aa71cb805c52a4a650e", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.101
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling ufmt-write v0.1.0
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling ufmt-macros v0.3.0
[INFO] [stderr]    Compiling ufmt v0.2.0
[INFO] [stderr]    Compiling panic-serial v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/lib.rs:97:1
[INFO] [stdout]    |
[INFO] [stdout] 97 | #![feature(panic_info_message)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `panic_info_message` has been stable since 1.81.0 and no longer requires an attribute to enable
[INFO] [stdout]   --> src/lib.rs:97:12
[INFO] [stdout]    |
[INFO] [stdout] 97 | #![feature(panic_info_message)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0308]: mismatched types
[INFO] [stdout]    --> src/lib.rs:124:16
[INFO] [stdout]     |
[INFO] [stdout] 124 |         if let Some(message) = info.message() {
[INFO] [stdout]     |                ^^^^^^^^^^^^^   -------------- this expression has type `PanicMessage<'_>`
[INFO] [stdout]     |                |
[INFO] [stdout]     |                expected `PanicMessage<'_>`, found `Option<_>`
[INFO] [stdout]     |
[INFO] [stdout]     = note: expected struct `PanicMessage<'_>`
[INFO] [stdout]                  found enum `Option<_>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0308, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0308`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `panic-serial` (lib) due to 2 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "425d0e5a9d053a1493bd637493d88dc0bac64031120f6aa71cb805c52a4a650e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "425d0e5a9d053a1493bd637493d88dc0bac64031120f6aa71cb805c52a4a650e", kill_on_drop: false }`
[INFO] [stdout] 425d0e5a9d053a1493bd637493d88dc0bac64031120f6aa71cb805c52a4a650e