[INFO] fetching crate rsubstitute 0.1.0...
[INFO] testing rsubstitute-0.1.0 against beta-2026-04-21 for beta-1.96-2
[INFO] extracting crate rsubstitute 0.1.0 into /workspace/builds/worker-3-tc2/source
[INFO] started tweaking crates.io crate rsubstitute 0.1.0
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate rsubstitute 0.1.0
[INFO] tweaked toml for crates.io crate rsubstitute 0.1.0 written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate rsubstitute 0.1.0 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] crate crates.io crate rsubstitute 0.1.0 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-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] d9a96de7562a03c6d3b59ffde47a4b7f57a98aed288e04a30b61adfb490ef794
[INFO] running `Command { std: "docker" "start" "-a" "d9a96de7562a03c6d3b59ffde47a4b7f57a98aed288e04a30b61adfb490ef794", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d9a96de7562a03c6d3b59ffde47a4b7f57a98aed288e04a30b61adfb490ef794", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d9a96de7562a03c6d3b59ffde47a4b7f57a98aed288e04a30b61adfb490ef794", kill_on_drop: false }`
[INFO] [stdout] d9a96de7562a03c6d3b59ffde47a4b7f57a98aed288e04a30b61adfb490ef794
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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] 4a9cf359c6492c02b13ee729c54244ecfe6c263990eabdba3b1517b7a9234bf2
[INFO] running `Command { std: "docker" "start" "-a" "4a9cf359c6492c02b13ee729c54244ecfe6c263990eabdba3b1517b7a9234bf2", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.104
[INFO] [stderr]    Compiling not_enough_asserts v1.1.1
[INFO] [stderr]    Compiling rsubstitute_core v0.1.0
[INFO] [stderr]    Compiling quote v1.0.42
[INFO] [stderr]    Compiling syn v2.0.111
[INFO] [stderr]    Compiling rsubstitute_proc_macro v0.1.0
[INFO] [stderr]    Compiling rsubstitute v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 9.20s
[INFO] running `Command { std: "docker" "inspect" "4a9cf359c6492c02b13ee729c54244ecfe6c263990eabdba3b1517b7a9234bf2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4a9cf359c6492c02b13ee729c54244ecfe6c263990eabdba3b1517b7a9234bf2", kill_on_drop: false }`
[INFO] [stdout] 4a9cf359c6492c02b13ee729c54244ecfe6c263990eabdba3b1517b7a9234bf2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 31c060d4207a38dd515ff23b987d27739089ca3c4e4dcf166e0f242c8c309326
[INFO] running `Command { std: "docker" "start" "-a" "31c060d4207a38dd515ff23b987d27739089ca3c4e4dcf166e0f242c8c309326", kill_on_drop: false }`
[INFO] [stderr]    Compiling rsubstitute_core v0.1.0
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/rsubstitute_core-0.1.0/src/lib.rs:3:39
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![cfg_attr(feature = "debug_naming", feature(specialization))]
[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 `rsubstitute_core` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "31c060d4207a38dd515ff23b987d27739089ca3c4e4dcf166e0f242c8c309326", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31c060d4207a38dd515ff23b987d27739089ca3c4e4dcf166e0f242c8c309326", kill_on_drop: false }`
[INFO] [stdout] 31c060d4207a38dd515ff23b987d27739089ca3c4e4dcf166e0f242c8c309326
