[INFO] fetching crate loveletter 0.2.0...
[INFO] testing loveletter-0.2.0 against beta-2025-10-28 for beta-1.92-2
[INFO] extracting crate loveletter 0.2.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate loveletter 0.2.0
[INFO] finished tweaking crates.io crate loveletter 0.2.0
[INFO] tweaked toml for crates.io crate loveletter 0.2.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate loveletter 0.2.0 on toolchain beta-2025-10-28
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-10-28" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate loveletter 0.2.0 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-2025-10-28" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-10-28" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 800ef50f4caa09221f633c7bf783b9243ac44c2cc4014dce5365fcf0a9b8f2db
[INFO] running `Command { std: "docker" "start" "-a" "800ef50f4caa09221f633c7bf783b9243ac44c2cc4014dce5365fcf0a9b8f2db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "800ef50f4caa09221f633c7bf783b9243ac44c2cc4014dce5365fcf0a9b8f2db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "800ef50f4caa09221f633c7bf783b9243ac44c2cc4014dce5365fcf0a9b8f2db", kill_on_drop: false }`
[INFO] [stdout] 800ef50f4caa09221f633c7bf783b9243ac44c2cc4014dce5365fcf0a9b8f2db
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-10-28" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 36e1f16c22a8565683f9c63d2f2ee0979407f6cf89143f5229dae72e8d6eeaa1
[INFO] running `Command { std: "docker" "start" "-a" "36e1f16c22a8565683f9c63d2f2ee0979407f6cf89143f5229dae72e8d6eeaa1", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.94
[INFO] [stderr]    Compiling libc v0.2.171
[INFO] [stderr]    Compiling serde v1.0.219
[INFO] [stderr]    Compiling openssl v0.10.71
[INFO] [stderr]    Compiling yansi v1.0.1
[INFO] [stderr]    Compiling cc v1.2.16
[INFO] [stderr]    Compiling proc-macro2-diagnostics v0.10.1
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stderr]    Compiling anstyle-parse v0.2.6
[INFO] [stderr]    Compiling aho-corasick v1.1.3
[INFO] [stderr]    Compiling once_cell v1.21.1
[INFO] [stderr]    Compiling time-core v0.1.4
[INFO] [stderr]    Compiling anstyle v1.0.10
[INFO] [stderr]    Compiling bitflags v2.9.0
[INFO] [stderr]    Compiling colorchoice v1.0.3
[INFO] [stderr]    Compiling hashbrown v0.15.2
[INFO] [stderr]    Compiling anstyle-query v1.1.2
[INFO] [stderr]    Compiling time-macros v0.2.22
[INFO] [stderr]    Compiling nom v7.1.3
[INFO] [stderr]    Compiling deranged v0.4.1
[INFO] [stderr]    Compiling anyhow v1.0.97
[INFO] [stderr]    Compiling signal-hook v0.3.17
[INFO] [stderr]    Compiling anstream v0.6.18
[INFO] [stderr]    Compiling aliasable v0.1.3
[INFO] [stderr]    Compiling num_threads v0.1.7
[INFO] [stderr]    Compiling strsim v0.11.1
[INFO] [stderr]    Compiling clap_lex v0.7.4
[INFO] [stderr]    Compiling winnow v0.7.4
[INFO] [stderr]    Compiling encoding_rs v0.8.35
[INFO] [stderr]    Compiling xshell-macros v0.2.7
[INFO] [stderr]    Compiling indexmap v2.8.0
[INFO] [stderr]    Compiling clap_builder v4.5.34
[INFO] [stderr]    Compiling bufstream v0.1.4
[INFO] [stderr]    Compiling quote v1.0.40
[INFO] [stderr]    Compiling xshell v0.2.7
[INFO] [stderr]    Compiling syn v2.0.100
[INFO] [stderr]    Compiling unicode-width v0.2.0
[INFO] [stderr]    Compiling signal-hook-registry v1.4.2
[INFO] [stderr]    Compiling regex-automata v0.4.9
[INFO] [stderr]    Compiling time v0.3.41
[INFO] [stderr]    Compiling openssl-sys v0.9.106
[INFO] [stderr]    Compiling native-tls v0.2.14
[INFO] [stderr]    Compiling imap-proto v0.16.5
[INFO] [stderr]    Compiling simplelog v0.12.2
[INFO] [stderr]    Compiling toml_datetime v0.6.8
[INFO] [stderr]    Compiling serde_spanned v0.6.8
[INFO] [stderr]    Compiling chrono v0.4.40
[INFO] [stderr]    Compiling email_address v0.2.9
[INFO] [stderr]    Compiling toml_edit v0.22.24
[INFO] [stderr]    Compiling openssl-macros v0.1.1
[INFO] [stderr]    Compiling ouroboros_macro v0.18.5
[INFO] [stderr]    Compiling clap_derive v4.5.32
[INFO] [stderr]    Compiling hashify v0.2.6
[INFO] [stderr]    Compiling serde_derive v1.0.219
[INFO] [stderr]    Compiling regex v1.11.1
[INFO] [stderr]    Compiling mail-parser v0.10.2
[INFO] [stderr]    Compiling clap v4.5.34
[INFO] [stderr]    Compiling ouroboros v0.18.5
[INFO] [stderr]    Compiling toml v0.8.20
[INFO] [stderr]    Compiling imap v3.0.0-alpha.15
[INFO] [stderr]    Compiling loveletter v0.2.0 (/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(pattern)]
[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 `loveletter` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "36e1f16c22a8565683f9c63d2f2ee0979407f6cf89143f5229dae72e8d6eeaa1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "36e1f16c22a8565683f9c63d2f2ee0979407f6cf89143f5229dae72e8d6eeaa1", kill_on_drop: false }`
[INFO] [stdout] 36e1f16c22a8565683f9c63d2f2ee0979407f6cf89143f5229dae72e8d6eeaa1
