[INFO] fetching crate katexit-example-nightly 0.1.4...
[INFO] testing katexit-example-nightly-0.1.4 against beta-2025-09-21 for beta-1.91-3
[INFO] extracting crate katexit-example-nightly 0.1.4 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate katexit-example-nightly 0.1.4
[INFO] finished tweaking crates.io crate katexit-example-nightly 0.1.4
[INFO] tweaked toml for crates.io crate katexit-example-nightly 0.1.4 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate katexit-example-nightly 0.1.4 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 5 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] e11ba3f2260b7c4e85b90ddc565f935d91f5d08db1fc1d0a8d3aef358e0c88bc
[INFO] running `Command { std: "docker" "start" "-a" "e11ba3f2260b7c4e85b90ddc565f935d91f5d08db1fc1d0a8d3aef358e0c88bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e11ba3f2260b7c4e85b90ddc565f935d91f5d08db1fc1d0a8d3aef358e0c88bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e11ba3f2260b7c4e85b90ddc565f935d91f5d08db1fc1d0a8d3aef358e0c88bc", kill_on_drop: false }`
[INFO] [stdout] e11ba3f2260b7c4e85b90ddc565f935d91f5d08db1fc1d0a8d3aef358e0c88bc
[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] b0bf5f1820515f3a75e3b80f07792b435d868a26b9c1a306becca6db94130c3d
[INFO] running `Command { std: "docker" "start" "-a" "b0bf5f1820515f3a75e3b80f07792b435d868a26b9c1a306becca6db94130c3d", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.101
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling unicode-ident v1.0.19
[INFO] [stderr]    Compiling syn v2.0.106
[INFO] [stderr]    Compiling katexit v0.1.5
[INFO] [stderr]    Compiling katexit-example-nightly v0.1.4 (/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(prelude_import, custom_inner_attributes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `prelude_import` is internal to the compiler or standard library
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(prelude_import, custom_inner_attributes)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: using it is strongly discouraged
[INFO] [stdout]   = note: `#[warn(internal_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `katexit-example-nightly` (lib) due to 1 previous error; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "b0bf5f1820515f3a75e3b80f07792b435d868a26b9c1a306becca6db94130c3d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b0bf5f1820515f3a75e3b80f07792b435d868a26b9c1a306becca6db94130c3d", kill_on_drop: false }`
[INFO] [stdout] b0bf5f1820515f3a75e3b80f07792b435d868a26b9c1a306becca6db94130c3d